diff options
Diffstat (limited to 'kernel')
87 files changed, 9497 insertions, 1856 deletions
diff --git a/kernel/audit.c b/kernel/audit.c index 678c3f000191..22bb4f24f071 100644 --- a/kernel/audit.c +++ b/kernel/audit.c @@ -64,7 +64,6 @@ #include <linux/security.h> #endif #include <linux/freezer.h> -#include <linux/tty.h> #include <linux/pid_namespace.h> #include <net/netns/generic.h> @@ -430,7 +429,6 @@ restart: attempts, audit_pid); set_current_state(TASK_INTERRUPTIBLE); schedule(); - __set_current_state(TASK_RUNNING); goto restart; } } @@ -1341,15 +1339,14 @@ static inline void audit_get_stamp(struct audit_context *ctx, static long wait_for_auditd(long sleep_time) { DECLARE_WAITQUEUE(wait, current); - set_current_state(TASK_UNINTERRUPTIBLE); - add_wait_queue_exclusive(&audit_backlog_wait, &wait); if (audit_backlog_limit && - skb_queue_len(&audit_skb_queue) > audit_backlog_limit) + skb_queue_len(&audit_skb_queue) > audit_backlog_limit) { + add_wait_queue_exclusive(&audit_backlog_wait, &wait); + set_current_state(TASK_UNINTERRUPTIBLE); sleep_time = schedule_timeout(sleep_time); - - __set_current_state(TASK_RUNNING); - remove_wait_queue(&audit_backlog_wait, &wait); + remove_wait_queue(&audit_backlog_wait, &wait); + } return sleep_time; } @@ -1890,21 +1887,14 @@ void audit_log_task_info(struct audit_buffer *ab, struct task_struct *tsk) { const struct cred *cred; char comm[sizeof(tsk->comm)]; - char *tty; + struct tty_struct *tty; if (!ab) return; /* tsk == current */ cred = current_cred(); - - spin_lock_irq(&tsk->sighand->siglock); - if (tsk->signal && tsk->signal->tty && tsk->signal->tty->name) - tty = tsk->signal->tty->name; - else - tty = "(none)"; - spin_unlock_irq(&tsk->sighand->siglock); - + tty = audit_get_tty(tsk); audit_log_format(ab, " ppid=%d pid=%d auid=%u uid=%u gid=%u" " euid=%u suid=%u fsuid=%u" @@ -1920,11 +1910,11 @@ void audit_log_task_info(struct audit_buffer *ab, struct task_struct *tsk) from_kgid(&init_user_ns, cred->egid), from_kgid(&init_user_ns, cred->sgid), from_kgid(&init_user_ns, cred->fsgid), - tty, audit_get_sessionid(tsk)); - + tty ? tty_name(tty) : "(none)", + audit_get_sessionid(tsk)); + audit_put_tty(tty); audit_log_format(ab, " comm="); audit_log_untrustedstring(ab, get_task_comm(comm, tsk)); - audit_log_d_path_exe(ab, tsk->mm); audit_log_task_context(ab); } diff --git a/kernel/audit_tree.c b/kernel/audit_tree.c index 5efe9b299a12..25772476fa4a 100644 --- a/kernel/audit_tree.c +++ b/kernel/audit_tree.c @@ -661,10 +661,10 @@ static int tag_mount(struct vfsmount *mnt, void *arg) static int prune_tree_thread(void *unused) { for (;;) { - set_current_state(TASK_INTERRUPTIBLE); - if (list_empty(&prune_list)) + if (list_empty(&prune_list)) { + set_current_state(TASK_INTERRUPTIBLE); schedule(); - __set_current_state(TASK_RUNNING); + } mutex_lock(&audit_cmd_mutex); mutex_lock(&audit_filter_mutex); @@ -693,16 +693,14 @@ static int audit_launch_prune(void) { if (prune_thread) return 0; - prune_thread = kthread_create(prune_tree_thread, NULL, + prune_thread = kthread_run(prune_tree_thread, NULL, "audit_prune_tree"); if (IS_ERR(prune_thread)) { pr_err("cannot start thread audit_prune_tree"); prune_thread = NULL; return -ENOMEM; - } else { - wake_up_process(prune_thread); - return 0; } + return 0; } /* called with audit_filter_mutex */ diff --git a/kernel/audit_watch.c b/kernel/audit_watch.c index 3cf1c5978d39..d6709eb70970 100644 --- a/kernel/audit_watch.c +++ b/kernel/audit_watch.c @@ -367,7 +367,7 @@ static int audit_get_nd(struct audit_watch *watch, struct path *parent) inode_unlock(d_backing_inode(parent->dentry)); if (d_is_positive(d)) { /* update watch filter fields */ - watch->dev = d_backing_inode(d)->i_sb->s_dev; + watch->dev = d->d_sb->s_dev; watch->ino = d_backing_inode(d)->i_ino; } dput(d); diff --git a/kernel/auditsc.c b/kernel/auditsc.c index 7d0e3cf8abe1..62ab53d7619c 100644 --- a/kernel/auditsc.c +++ b/kernel/auditsc.c @@ -1980,6 +1980,7 @@ static void audit_log_set_loginuid(kuid_t koldloginuid, kuid_t kloginuid, { struct audit_buffer *ab; uid_t uid, oldloginuid, loginuid; + struct tty_struct *tty; if (!audit_enabled) return; @@ -1987,14 +1988,17 @@ static void audit_log_set_loginuid(kuid_t koldloginuid, kuid_t kloginuid, uid = from_kuid(&init_user_ns, task_uid(current)); oldloginuid = from_kuid(&init_user_ns, koldloginuid); loginuid = from_kuid(&init_user_ns, kloginuid), + tty = audit_get_tty(current); ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_LOGIN); if (!ab) return; audit_log_format(ab, "pid=%d uid=%u", task_pid_nr(current), uid); audit_log_task_context(ab); - audit_log_format(ab, " old-auid=%u auid=%u old-ses=%u ses=%u res=%d", - oldloginuid, loginuid, oldsessionid, sessionid, !rc); + audit_log_format(ab, " old-auid=%u auid=%u tty=%s old-ses=%u ses=%u res=%d", + oldloginuid, loginuid, tty ? tty_name(tty) : "(none)", + oldsessionid, sessionid, !rc); + audit_put_tty(tty); audit_log_end(ab); } diff --git a/kernel/bpf/core.c b/kernel/bpf/core.c index be0abf669ced..f1e8a0def99b 100644 --- a/kernel/bpf/core.c +++ b/kernel/bpf/core.c @@ -129,14 +129,83 @@ struct bpf_prog *bpf_prog_realloc(struct bpf_prog *fp_old, unsigned int size, return fp; } -EXPORT_SYMBOL_GPL(bpf_prog_realloc); void __bpf_prog_free(struct bpf_prog *fp) { kfree(fp->aux); vfree(fp); } -EXPORT_SYMBOL_GPL(__bpf_prog_free); + +static bool bpf_is_jmp_and_has_target(const struct bpf_insn *insn) +{ + return BPF_CLASS(insn->code) == BPF_JMP && + /* Call and Exit are both special jumps with no + * target inside the BPF instruction image. + */ + BPF_OP(insn->code) != BPF_CALL && + BPF_OP(insn->code) != BPF_EXIT; +} + +static void bpf_adj_branches(struct bpf_prog *prog, u32 pos, u32 delta) +{ + struct bpf_insn *insn = prog->insnsi; + u32 i, insn_cnt = prog->len; + + for (i = 0; i < insn_cnt; i++, insn++) { + if (!bpf_is_jmp_and_has_target(insn)) + continue; + + /* Adjust offset of jmps if we cross boundaries. */ + if (i < pos && i + insn->off + 1 > pos) + insn->off += delta; + else if (i > pos + delta && i + insn->off + 1 <= pos + delta) + insn->off -= delta; + } +} + +struct bpf_prog *bpf_patch_insn_single(struct bpf_prog *prog, u32 off, + const struct bpf_insn *patch, u32 len) +{ + u32 insn_adj_cnt, insn_rest, insn_delta = len - 1; + struct bpf_prog *prog_adj; + + /* Since our patchlet doesn't expand the image, we're done. */ + if (insn_delta == 0) { + memcpy(prog->insnsi + off, patch, sizeof(*patch)); + return prog; + } + + insn_adj_cnt = prog->len + insn_delta; + + /* Several new instructions need to be inserted. Make room + * for them. Likely, there's no need for a new allocation as + * last page could have large enough tailroom. + */ + prog_adj = bpf_prog_realloc(prog, bpf_prog_size(insn_adj_cnt), + GFP_USER); + if (!prog_adj) + return NULL; + + prog_adj->len = insn_adj_cnt; + + /* Patching happens in 3 steps: + * + * 1) Move over tail of insnsi from next instruction onwards, + * so we can patch the single target insn with one or more + * new ones (patching is always from 1 to n insns, n > 0). + * 2) Inject new instructions at the target location. + * 3) Adjust branch offsets if necessary. + */ + insn_rest = insn_adj_cnt - off - len; + + memmove(prog_adj->insnsi + off + len, prog_adj->insnsi + off + 1, + sizeof(*patch) * insn_rest); + memcpy(prog_adj->insnsi + off, patch, sizeof(*patch) * len); + + bpf_adj_branches(prog_adj, off, insn_delta); + + return prog_adj; +} #ifdef CONFIG_BPF_JIT struct bpf_binary_header * @@ -174,6 +243,209 @@ void bpf_jit_binary_free(struct bpf_binary_header *hdr) { module_memfree(hdr); } + +int bpf_jit_harden __read_mostly; + +static int bpf_jit_blind_insn(const struct bpf_insn *from, + const struct bpf_insn *aux, + struct bpf_insn *to_buff) +{ + struct bpf_insn *to = to_buff; + u32 imm_rnd = prandom_u32(); + s16 off; + + BUILD_BUG_ON(BPF_REG_AX + 1 != MAX_BPF_JIT_REG); + BUILD_BUG_ON(MAX_BPF_REG + 1 != MAX_BPF_JIT_REG); + + if (from->imm == 0 && + (from->code == (BPF_ALU | BPF_MOV | BPF_K) || + from->code == (BPF_ALU64 | BPF_MOV | BPF_K))) { + *to++ = BPF_ALU64_REG(BPF_XOR, from->dst_reg, from->dst_reg); + goto out; + } + + switch (from->code) { + case BPF_ALU | BPF_ADD | BPF_K: + case BPF_ALU | BPF_SUB | BPF_K: + case BPF_ALU | BPF_AND | BPF_K: + case BPF_ALU | BPF_OR | BPF_K: + case BPF_ALU | BPF_XOR | BPF_K: + case BPF_ALU | BPF_MUL | BPF_K: + case BPF_ALU | BPF_MOV | BPF_K: + case BPF_ALU | BPF_DIV | BPF_K: + case BPF_ALU | BPF_MOD | BPF_K: + *to++ = BPF_ALU32_IMM(BPF_MOV, BPF_REG_AX, imm_rnd ^ from->imm); + *to++ = BPF_ALU32_IMM(BPF_XOR, BPF_REG_AX, imm_rnd); + *to++ = BPF_ALU32_REG(from->code, from->dst_reg, BPF_REG_AX); + break; + + case BPF_ALU64 | BPF_ADD | BPF_K: + case BPF_ALU64 | BPF_SUB | BPF_K: + case BPF_ALU64 | BPF_AND | BPF_K: + case BPF_ALU64 | BPF_OR | BPF_K: + case BPF_ALU64 | BPF_XOR | BPF_K: + case BPF_ALU64 | BPF_MUL | BPF_K: + case BPF_ALU64 | BPF_MOV | BPF_K: + case BPF_ALU64 | BPF_DIV | BPF_K: + case BPF_ALU64 | BPF_MOD | BPF_K: + *to++ = BPF_ALU64_IMM(BPF_MOV, BPF_REG_AX, imm_rnd ^ from->imm); + *to++ = BPF_ALU64_IMM(BPF_XOR, BPF_REG_AX, imm_rnd); + *to++ = BPF_ALU64_REG(from->code, from->dst_reg, BPF_REG_AX); + break; + + case BPF_JMP | BPF_JEQ | BPF_K: + case BPF_JMP | BPF_JNE | BPF_K: + case BPF_JMP | BPF_JGT | BPF_K: + case BPF_JMP | BPF_JGE | BPF_K: + case BPF_JMP | BPF_JSGT | BPF_K: + case BPF_JMP | BPF_JSGE | BPF_K: + case BPF_JMP | BPF_JSET | BPF_K: + /* Accommodate for extra offset in case of a backjump. */ + off = from->off; + if (off < 0) + off -= 2; + *to++ = BPF_ALU64_IMM(BPF_MOV, BPF_REG_AX, imm_rnd ^ from->imm); + *to++ = BPF_ALU64_IMM(BPF_XOR, BPF_REG_AX, imm_rnd); + *to++ = BPF_JMP_REG(from->code, from->dst_reg, BPF_REG_AX, off); + break; + + case BPF_LD | BPF_ABS | BPF_W: + case BPF_LD | BPF_ABS | BPF_H: + case BPF_LD | BPF_ABS | BPF_B: + *to++ = BPF_ALU64_IMM(BPF_MOV, BPF_REG_AX, imm_rnd ^ from->imm); + *to++ = BPF_ALU64_IMM(BPF_XOR, BPF_REG_AX, imm_rnd); + *to++ = BPF_LD_IND(from->code, BPF_REG_AX, 0); + break; + + case BPF_LD | BPF_IND | BPF_W: + case BPF_LD | BPF_IND | BPF_H: + case BPF_LD | BPF_IND | BPF_B: + *to++ = BPF_ALU64_IMM(BPF_MOV, BPF_REG_AX, imm_rnd ^ from->imm); + *to++ = BPF_ALU64_IMM(BPF_XOR, BPF_REG_AX, imm_rnd); + *to++ = BPF_ALU32_REG(BPF_ADD, BPF_REG_AX, from->src_reg); + *to++ = BPF_LD_IND(from->code, BPF_REG_AX, 0); + break; + + case BPF_LD | BPF_IMM | BPF_DW: + *to++ = BPF_ALU64_IMM(BPF_MOV, BPF_REG_AX, imm_rnd ^ aux[1].imm); + *to++ = BPF_ALU64_IMM(BPF_XOR, BPF_REG_AX, imm_rnd); + *to++ = BPF_ALU64_IMM(BPF_LSH, BPF_REG_AX, 32); + *to++ = BPF_ALU64_REG(BPF_MOV, aux[0].dst_reg, BPF_REG_AX); + break; + case 0: /* Part 2 of BPF_LD | BPF_IMM | BPF_DW. */ + *to++ = BPF_ALU32_IMM(BPF_MOV, BPF_REG_AX, imm_rnd ^ aux[0].imm); + *to++ = BPF_ALU32_IMM(BPF_XOR, BPF_REG_AX, imm_rnd); + *to++ = BPF_ALU64_REG(BPF_OR, aux[0].dst_reg, BPF_REG_AX); + break; + + case BPF_ST | BPF_MEM | BPF_DW: + case BPF_ST | BPF_MEM | BPF_W: + case BPF_ST | BPF_MEM | BPF_H: + case BPF_ST | BPF_MEM | BPF_B: + *to++ = BPF_ALU64_IMM(BPF_MOV, BPF_REG_AX, imm_rnd ^ from->imm); + *to++ = BPF_ALU64_IMM(BPF_XOR, BPF_REG_AX, imm_rnd); + *to++ = BPF_STX_MEM(from->code, from->dst_reg, BPF_REG_AX, from->off); + break; + } +out: + return to - to_buff; +} + +static struct bpf_prog *bpf_prog_clone_create(struct bpf_prog *fp_other, + gfp_t gfp_extra_flags) +{ + gfp_t gfp_flags = GFP_KERNEL | __GFP_HIGHMEM | __GFP_ZERO | + gfp_extra_flags; + struct bpf_prog *fp; + + fp = __vmalloc(fp_other->pages * PAGE_SIZE, gfp_flags, PAGE_KERNEL); + if (fp != NULL) { + kmemcheck_annotate_bitfield(fp, meta); + + /* aux->prog still points to the fp_other one, so + * when promoting the clone to the real program, + * this still needs to be adapted. + */ + memcpy(fp, fp_other, fp_other->pages * PAGE_SIZE); + } + + return fp; +} + +static void bpf_prog_clone_free(struct bpf_prog *fp) +{ + /* aux was stolen by the other clone, so we cannot free + * it from this path! It will be freed eventually by the + * other program on release. + * + * At this point, we don't need a deferred release since + * clone is guaranteed to not be locked. + */ + fp->aux = NULL; + __bpf_prog_free(fp); +} + +void bpf_jit_prog_release_other(struct bpf_prog *fp, struct bpf_prog *fp_other) +{ + /* We have to repoint aux->prog to self, as we don't + * know whether fp here is the clone or the original. + */ + fp->aux->prog = fp; + bpf_prog_clone_free(fp_other); +} + +struct bpf_prog *bpf_jit_blind_constants(struct bpf_prog *prog) +{ + struct bpf_insn insn_buff[16], aux[2]; + struct bpf_prog *clone, *tmp; + int insn_delta, insn_cnt; + struct bpf_insn *insn; + int i, rewritten; + + if (!bpf_jit_blinding_enabled()) + return prog; + + clone = bpf_prog_clone_create(prog, GFP_USER); + if (!clone) + return ERR_PTR(-ENOMEM); + + insn_cnt = clone->len; + insn = clone->insnsi; + + for (i = 0; i < insn_cnt; i++, insn++) { + /* We temporarily need to hold the original ld64 insn + * so that we can still access the first part in the + * second blinding run. + */ + if (insn[0].code == (BPF_LD | BPF_IMM | BPF_DW) && + insn[1].code == 0) + memcpy(aux, insn, sizeof(aux)); + + rewritten = bpf_jit_blind_insn(insn, aux, insn_buff); + if (!rewritten) + continue; + + tmp = bpf_patch_insn_single(clone, i, insn_buff, rewritten); + if (!tmp) { + /* Patching may have repointed aux->prog during + * realloc from the original one, so we need to + * fix it up here on error. + */ + bpf_jit_prog_release_other(prog, clone); + return ERR_PTR(-ENOMEM); + } + + clone = tmp; + insn_delta = rewritten - 1; + + /* Walk new program and skip insns we just inserted. */ + insn = clone->insnsi + i + insn_delta; + insn_cnt += insn_delta; + i += insn_delta; + } + + return clone; +} #endif /* CONFIG_BPF_JIT */ /* Base function for offset calculation. Needs to go into .text section, @@ -692,15 +964,22 @@ static int bpf_check_tail_call(const struct bpf_prog *fp) /** * bpf_prog_select_runtime - select exec runtime for BPF program * @fp: bpf_prog populated with internal BPF program + * @err: pointer to error variable * * Try to JIT eBPF program, if JIT is not available, use interpreter. * The BPF program will be executed via BPF_PROG_RUN() macro. */ -int bpf_prog_select_runtime(struct bpf_prog *fp) +struct bpf_prog *bpf_prog_select_runtime(struct bpf_prog *fp, int *err) { fp->bpf_func = (void *) __bpf_prog_run; - bpf_int_jit_compile(fp); + /* eBPF JITs can rewrite the program in case constant + * blinding is active. However, in case of error during + * blinding, bpf_int_jit_compile() must always return a + * valid program, which in this case would simply not + * be JITed, but falls back to the interpreter. + */ + fp = bpf_int_jit_compile(fp); bpf_prog_lock_ro(fp); /* The tail call compatibility check can only be done at @@ -708,7 +987,9 @@ int bpf_prog_select_runtime(struct bpf_prog *fp) * with JITed or non JITed program concatenations and not * all eBPF JITs might immediately support all features. */ - return bpf_check_tail_call(fp); + *err = bpf_check_tail_call(fp); + + return fp; } EXPORT_SYMBOL_GPL(bpf_prog_select_runtime); @@ -764,14 +1045,21 @@ const struct bpf_func_proto bpf_map_delete_elem_proto __weak; const struct bpf_func_proto bpf_get_prandom_u32_proto __weak; const struct bpf_func_proto bpf_get_smp_processor_id_proto __weak; const struct bpf_func_proto bpf_ktime_get_ns_proto __weak; + const struct bpf_func_proto bpf_get_current_pid_tgid_proto __weak; const struct bpf_func_proto bpf_get_current_uid_gid_proto __weak; const struct bpf_func_proto bpf_get_current_comm_proto __weak; + const struct bpf_func_proto * __weak bpf_get_trace_printk_proto(void) { return NULL; } +const struct bpf_func_proto * __weak bpf_get_event_output_proto(void) +{ + return NULL; +} + /* Always built-in helper functions. */ const struct bpf_func_proto bpf_tail_call_proto = { .func = NULL, @@ -783,8 +1071,14 @@ const struct bpf_func_proto bpf_tail_call_proto = { }; /* For classic BPF JITs that don't implement bpf_int_jit_compile(). */ -void __weak bpf_int_jit_compile(struct bpf_prog *prog) +struct bpf_prog * __weak bpf_int_jit_compile(struct bpf_prog *prog) +{ + return prog; +} + +bool __weak bpf_helper_changes_skb_data(void *func) { + return false; } /* To execute LD_ABS/LD_IND instructions __bpf_prog_run() may call diff --git a/kernel/bpf/helpers.c b/kernel/bpf/helpers.c index 50da680c479f..ad7a0573f71b 100644 --- a/kernel/bpf/helpers.c +++ b/kernel/bpf/helpers.c @@ -163,17 +163,26 @@ static u64 bpf_get_current_comm(u64 r1, u64 size, u64 r3, u64 r4, u64 r5) struct task_struct *task = current; char *buf = (char *) (long) r1; - if (!task) - return -EINVAL; + if (unlikely(!task)) + goto err_clear; - strlcpy(buf, task->comm, min_t(size_t, size, sizeof(task->comm))); + strncpy(buf, task->comm, size); + + /* Verifier guarantees that size > 0. For task->comm exceeding + * size, guarantee that buf is %NUL-terminated. Unconditionally + * done here to save the size test. + */ + buf[size - 1] = 0; return 0; +err_clear: + memset(buf, 0, size); + return -EINVAL; } const struct bpf_func_proto bpf_get_current_comm_proto = { .func = bpf_get_current_comm, .gpl_only = false, .ret_type = RET_INTEGER, - .arg1_type = ARG_PTR_TO_STACK, + .arg1_type = ARG_PTR_TO_RAW_STACK, .arg2_type = ARG_CONST_STACK_SIZE, }; diff --git a/kernel/bpf/inode.c b/kernel/bpf/inode.c index f2ece3c174a5..71b75d9c81da 100644 --- a/kernel/bpf/inode.c +++ b/kernel/bpf/inode.c @@ -31,10 +31,10 @@ static void *bpf_any_get(void *raw, enum bpf_type type) { switch (type) { case BPF_TYPE_PROG: - atomic_inc(&((struct bpf_prog *)raw)->aux->refcnt); + raw = bpf_prog_inc(raw); break; case BPF_TYPE_MAP: - bpf_map_inc(raw, true); + raw = bpf_map_inc(raw, true); break; default: WARN_ON_ONCE(1); @@ -119,18 +119,10 @@ static int bpf_inode_type(const struct inode *inode, enum bpf_type *type) return 0; } -static bool bpf_dname_reserved(const struct dentry *dentry) -{ - return strchr(dentry->d_name.name, '.'); -} - static int bpf_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode) { struct inode *inode; - if (bpf_dname_reserved(dentry)) - return -EPERM; - inode = bpf_get_inode(dir->i_sb, dir, mode | S_IFDIR); if (IS_ERR(inode)) return PTR_ERR(inode); @@ -152,9 +144,6 @@ static int bpf_mkobj_ops(struct inode *dir, struct dentry *dentry, { struct inode *inode; - if (bpf_dname_reserved(dentry)) - return -EPERM; - inode = bpf_get_inode(dir->i_sb, dir, mode | S_IFREG); if (IS_ERR(inode)) return PTR_ERR(inode); @@ -187,31 +176,21 @@ static int bpf_mkobj(struct inode *dir, struct dentry *dentry, umode_t mode, } } -static int bpf_link(struct dentry *old_dentry, struct inode *dir, - struct dentry *new_dentry) +static struct dentry * +bpf_lookup(struct inode *dir, struct dentry *dentry, unsigned flags) { - if (bpf_dname_reserved(new_dentry)) - return -EPERM; - - return simple_link(old_dentry, dir, new_dentry); -} - -static int bpf_rename(struct inode *old_dir, struct dentry *old_dentry, - struct inode *new_dir, struct dentry *new_dentry) -{ - if (bpf_dname_reserved(new_dentry)) - return -EPERM; - - return simple_rename(old_dir, old_dentry, new_dir, new_dentry); + if (strchr(dentry->d_name.name, '.')) + return ERR_PTR(-EPERM); + return simple_lookup(dir, dentry, flags); } static const struct inode_operations bpf_dir_iops = { - .lookup = simple_lookup, + .lookup = bpf_lookup, .mknod = bpf_mkobj, .mkdir = bpf_mkdir, .rmdir = simple_rmdir, - .rename = bpf_rename, - .link = bpf_link, + .rename = simple_rename, + .link = simple_link, .unlink = simple_unlink, }; @@ -297,7 +276,8 @@ static void *bpf_obj_do_get(const struct filename *pathname, goto out; raw = bpf_any_get(inode->i_private, *type); - touch_atime(&path); + if (!IS_ERR(raw)) + touch_atime(&path); path_put(&path); return raw; diff --git a/kernel/bpf/stackmap.c b/kernel/bpf/stackmap.c index 499d9e933f8e..c8ee35287bfe 100644 --- a/kernel/bpf/stackmap.c +++ b/kernel/bpf/stackmap.c @@ -66,7 +66,7 @@ static struct bpf_map *stack_map_alloc(union bpf_attr *attr) /* check sanity of attributes */ if (attr->max_entries == 0 || attr->key_size != 4 || value_size < 8 || value_size % 8 || - value_size / 8 > PERF_MAX_STACK_DEPTH) + value_size / 8 > sysctl_perf_event_max_stack) return ERR_PTR(-EINVAL); /* hash table size must be power of 2 */ @@ -116,7 +116,7 @@ free_smap: return ERR_PTR(err); } -static u64 bpf_get_stackid(u64 r1, u64 r2, u64 flags, u64 r4, u64 r5) +u64 bpf_get_stackid(u64 r1, u64 r2, u64 flags, u64 r4, u64 r5) { struct pt_regs *regs = (struct pt_regs *) (long) r1; struct bpf_map *map = (struct bpf_map *) (long) r2; @@ -124,8 +124,8 @@ static u64 bpf_get_stackid(u64 r1, u64 r2, u64 flags, u64 r4, u64 r5) struct perf_callchain_entry *trace; struct stack_map_bucket *bucket, *new_bucket, *old_bucket; u32 max_depth = map->value_size / 8; - /* stack_map_alloc() checks that max_depth <= PERF_MAX_STACK_DEPTH */ - u32 init_nr = PERF_MAX_STACK_DEPTH - max_depth; + /* stack_map_alloc() checks that max_depth <= sysctl_perf_event_max_stack */ + u32 init_nr = sysctl_perf_event_max_stack - max_depth; u32 skip = flags & BPF_F_SKIP_FIELD_MASK; u32 hash, id, trace_nr, trace_len; bool user = flags & BPF_F_USER_STACK; @@ -143,7 +143,7 @@ static u64 bpf_get_stackid(u64 r1, u64 r2, u64 flags, u64 r4, u64 r5) return -EFAULT; /* get_perf_callchain() guarantees that trace->nr >= init_nr - * and trace-nr <= PERF_MAX_STACK_DEPTH, so trace_nr <= max_depth + * and trace-nr <= sysctl_perf_event_max_stack, so trace_nr <= max_depth */ trace_nr = trace->nr - init_nr; diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c index adc5e4bd74f8..46ecce4b79ed 100644 --- a/kernel/bpf/syscall.c +++ b/kernel/bpf/syscall.c @@ -218,11 +218,18 @@ struct bpf_map *__bpf_map_get(struct fd f) return f.file->private_data; } -void bpf_map_inc(struct bpf_map *map, bool uref) +/* prog's and map's refcnt limit */ +#define BPF_MAX_REFCNT 32768 + +struct bpf_map *bpf_map_inc(struct bpf_map *map, bool uref) { - atomic_inc(&map->refcnt); + if (atomic_inc_return(&map->refcnt) > BPF_MAX_REFCNT) { + atomic_dec(&map->refcnt); + return ERR_PTR(-EBUSY); + } if (uref) atomic_inc(&map->usercnt); + return map; } struct bpf_map *bpf_map_get_with_uref(u32 ufd) @@ -234,7 +241,7 @@ struct bpf_map *bpf_map_get_with_uref(u32 ufd) if (IS_ERR(map)) return map; - bpf_map_inc(map, true); + map = bpf_map_inc(map, true); fdput(f); return map; @@ -658,6 +665,15 @@ static struct bpf_prog *__bpf_prog_get(struct fd f) return f.file->private_data; } +struct bpf_prog *bpf_prog_inc(struct bpf_prog *prog) +{ + if (atomic_inc_return(&prog->aux->refcnt) > BPF_MAX_REFCNT) { + atomic_dec(&prog->aux->refcnt); + return ERR_PTR(-EBUSY); + } + return prog; +} + /* called by sockets/tracing/seccomp before attaching program to an event * pairs with bpf_prog_put() */ @@ -670,7 +686,7 @@ struct bpf_prog *bpf_prog_get(u32 ufd) if (IS_ERR(prog)) return prog; - atomic_inc(&prog->aux->refcnt); + prog = bpf_prog_inc(prog); fdput(f); return prog; @@ -746,7 +762,7 @@ static int bpf_prog_load(union bpf_attr *attr) fixup_bpf_calls(prog); /* eBPF program is ready to be JITed */ - err = bpf_prog_select_runtime(prog); + prog = bpf_prog_select_runtime(prog, &err); if (err < 0) goto free_used_maps; diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c index 2e08f8e9b771..a08d66215245 100644 --- a/kernel/bpf/verifier.c +++ b/kernel/bpf/verifier.c @@ -1,4 +1,5 @@ /* Copyright (c) 2011-2014 PLUMgrid, http://plumgrid.com + * Copyright (c) 2016 Facebook * * This program is free software; you can redistribute it and/or * modify it under the terms of version 2 of the GNU General Public @@ -136,13 +137,32 @@ enum bpf_reg_type { FRAME_PTR, /* reg == frame_pointer */ PTR_TO_STACK, /* reg == frame_pointer + imm */ CONST_IMM, /* constant integer value */ + + /* PTR_TO_PACKET represents: + * skb->data + * skb->data + imm + * skb->data + (u16) var + * skb->data + (u16) var + imm + * if (range > 0) then [ptr, ptr + range - off) is safe to access + * if (id > 0) means that some 'var' was added + * if (off > 0) menas that 'imm' was added + */ + PTR_TO_PACKET, + PTR_TO_PACKET_END, /* skb->data + headlen */ }; struct reg_state { enum bpf_reg_type type; union { - /* valid when type == CONST_IMM | PTR_TO_STACK */ - int imm; + /* valid when type == CONST_IMM | PTR_TO_STACK | UNKNOWN_VALUE */ + s64 imm; + + /* valid when type == PTR_TO_PACKET* */ + struct { + u32 id; + u16 off; + u16 range; + }; /* valid when type == CONST_PTR_TO_MAP | PTR_TO_MAP_VALUE | * PTR_TO_MAP_VALUE_OR_NULL @@ -202,6 +222,16 @@ struct verifier_env { bool allow_ptr_leaks; }; +#define BPF_COMPLEXITY_LIMIT_INSNS 65536 +#define BPF_COMPLEXITY_LIMIT_STACK 1024 + +struct bpf_call_arg_meta { + struct bpf_map *map_ptr; + bool raw_mode; + int regno; + int access_size; +}; + /* verbose verifier prints what it's seeing * bpf_check() is called under lock, so no race to access these global vars */ @@ -237,40 +267,39 @@ static const char * const reg_type_str[] = { [FRAME_PTR] = "fp", [PTR_TO_STACK] = "fp", [CONST_IMM] = "imm", + [PTR_TO_PACKET] = "pkt", + [PTR_TO_PACKET_END] = "pkt_end", }; -static const struct { - int map_type; - int func_id; -} func_limit[] = { - {BPF_MAP_TYPE_PROG_ARRAY, BPF_FUNC_tail_call}, - {BPF_MAP_TYPE_PERF_EVENT_ARRAY, BPF_FUNC_perf_event_read}, - {BPF_MAP_TYPE_PERF_EVENT_ARRAY, BPF_FUNC_perf_event_output}, - {BPF_MAP_TYPE_STACK_TRACE, BPF_FUNC_get_stackid}, -}; - -static void print_verifier_state(struct verifier_env *env) +static void print_verifier_state(struct verifier_state *state) { + struct reg_state *reg; enum bpf_reg_type t; int i; for (i = 0; i < MAX_BPF_REG; i++) { - t = env->cur_state.regs[i].type; + reg = &state->regs[i]; + t = reg->type; if (t == NOT_INIT) continue; verbose(" R%d=%s", i, reg_type_str[t]); if (t == CONST_IMM || t == PTR_TO_STACK) - verbose("%d", env->cur_state.regs[i].imm); + verbose("%lld", reg->imm); + else if (t == PTR_TO_PACKET) + verbose("(id=%d,off=%d,r=%d)", + reg->id, reg->off, reg->range); + else if (t == UNKNOWN_VALUE && reg->imm) + verbose("%lld", reg->imm); else if (t == CONST_PTR_TO_MAP || t == PTR_TO_MAP_VALUE || t == PTR_TO_MAP_VALUE_OR_NULL) verbose("(ks=%d,vs=%d)", - env->cur_state.regs[i].map_ptr->key_size, - env->cur_state.regs[i].map_ptr->value_size); + reg->map_ptr->key_size, + reg->map_ptr->value_size); } for (i = 0; i < MAX_BPF_STACK; i += BPF_REG_SIZE) { - if (env->cur_state.stack_slot_type[i] == STACK_SPILL) + if (state->stack_slot_type[i] == STACK_SPILL) verbose(" fp%d=%s", -MAX_BPF_STACK + i, - reg_type_str[env->cur_state.spilled_regs[i / BPF_REG_SIZE].type]); + reg_type_str[state->spilled_regs[i / BPF_REG_SIZE].type]); } verbose("\n"); } @@ -454,7 +483,7 @@ static struct verifier_state *push_stack(struct verifier_env *env, int insn_idx, elem->next = env->head; env->head = elem; env->stack_size++; - if (env->stack_size > 1024) { + if (env->stack_size > BPF_COMPLEXITY_LIMIT_STACK) { verbose("BPF program is too complex\n"); goto err; } @@ -477,7 +506,6 @@ static void init_reg_state(struct reg_state *regs) for (i = 0; i < MAX_BPF_REG; i++) { regs[i].type = NOT_INIT; regs[i].imm = 0; - regs[i].map_ptr = NULL; } /* frame pointer */ @@ -492,7 +520,6 @@ static void mark_reg_unknown_value(struct reg_state *regs, u32 regno) BUG_ON(regno >= MAX_BPF_REG); regs[regno].type = UNKNOWN_VALUE; regs[regno].imm = 0; - regs[regno].map_ptr = NULL; } enum reg_arg_type { @@ -548,6 +575,8 @@ static bool is_spillable_regtype(enum bpf_reg_type type) case PTR_TO_MAP_VALUE_OR_NULL: case PTR_TO_STACK: case PTR_TO_CTX: + case PTR_TO_PACKET: + case PTR_TO_PACKET_END: case FRAME_PTR: case CONST_PTR_TO_MAP: return true; @@ -647,13 +676,38 @@ static int check_map_access(struct verifier_env *env, u32 regno, int off, return 0; } +#define MAX_PACKET_OFF 0xffff + +static int check_packet_access(struct verifier_env *env, u32 regno, int off, + int size) +{ + struct reg_state *regs = env->cur_state.regs; + struct reg_state *reg = ®s[regno]; + int linear_size = (int) reg->range - (int) reg->off; + + if (linear_size < 0 || linear_size >= MAX_PACKET_OFF) { + verbose("verifier bug\n"); + return -EFAULT; + } + if (off < 0 || off + size > linear_size) { + verbose("invalid access to packet, off=%d size=%d, allowed=%d\n", + off, size, linear_size); + return -EACCES; + } + return 0; +} + /* check access to 'struct bpf_context' fields */ static int check_ctx_access(struct verifier_env *env, int off, int size, enum bpf_access_type t) { if (env->prog->aux->ops->is_valid_access && - env->prog->aux->ops->is_valid_access(off, size, t)) + env->prog->aux->ops->is_valid_access(off, size, t)) { + /* remember the offset of last byte accessed in ctx */ + if (env->prog->aux->max_ctx_offset < off + size) + env->prog->aux->max_ctx_offset = off + size; return 0; + } verbose("invalid bpf_context access off=%d size=%d\n", off, size); return -EACCES; @@ -673,6 +727,45 @@ static bool is_pointer_value(struct verifier_env *env, int regno) } } +static int check_ptr_alignment(struct verifier_env *env, struct reg_state *reg, + int off, int size) +{ + if (reg->type != PTR_TO_PACKET) { + if (off % size != 0) { + verbose("misaligned access off %d size %d\n", off, size); + return -EACCES; + } else { + return 0; + } + } + + switch (env->prog->type) { + case BPF_PROG_TYPE_SCHED_CLS: + case BPF_PROG_TYPE_SCHED_ACT: + break; + default: + verbose("verifier is misconfigured\n"); + return -EACCES; + } + + if (IS_ENABLED(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS)) + /* misaligned access to packet is ok on x86,arm,arm64 */ + return 0; + + if (reg->id && size != 1) { + verbose("Unknown packet alignment. Only byte-sized access allowed\n"); + return -EACCES; + } + + /* skb->data is NET_IP_ALIGN-ed */ + if ((NET_IP_ALIGN + reg->off + off) % size != 0) { + verbose("misaligned packet access off %d+%d+%d size %d\n", + NET_IP_ALIGN, reg->off, off, size); + return -EACCES; + } + return 0; +} + /* check whether memory at (regno + off) is accessible for t = (read | write) * if t==write, value_regno is a register which value is stored into memory * if t==read, value_regno is a register which will receive the value from memory @@ -684,21 +777,21 @@ static int check_mem_access(struct verifier_env *env, u32 regno, int off, int value_regno) { struct verifier_state *state = &env->cur_state; + struct reg_state *reg = &state->regs[regno]; int size, err = 0; - if (state->regs[regno].type == PTR_TO_STACK) - off += state->regs[regno].imm; + if (reg->type == PTR_TO_STACK) + off += reg->imm; size = bpf_size_to_bytes(bpf_size); if (size < 0) return size; - if (off % size != 0) { - verbose("misaligned access off %d size %d\n", off, size); - return -EACCES; - } + err = check_ptr_alignment(env, reg, off, size); + if (err) + return err; - if (state->regs[regno].type == PTR_TO_MAP_VALUE) { + if (reg->type == PTR_TO_MAP_VALUE) { if (t == BPF_WRITE && value_regno >= 0 && is_pointer_value(env, value_regno)) { verbose("R%d leaks addr into map\n", value_regno); @@ -708,18 +801,25 @@ static int check_mem_access(struct verifier_env *env, u32 regno, int off, if (!err && t == BPF_READ && value_regno >= 0) mark_reg_unknown_value(state->regs, value_regno); - } else if (state->regs[regno].type == PTR_TO_CTX) { + } else if (reg->type == PTR_TO_CTX) { if (t == BPF_WRITE && value_regno >= 0 && is_pointer_value(env, value_regno)) { verbose("R%d leaks addr into ctx\n", value_regno); return -EACCES; } err = check_ctx_access(env, off, size, t); - if (!err && t == BPF_READ && value_regno >= 0) + if (!err && t == BPF_READ && value_regno >= 0) { mark_reg_unknown_value(state->regs, value_regno); + if (off == offsetof(struct __sk_buff, data) && + env->allow_ptr_leaks) + /* note that reg.[id|off|range] == 0 */ + state->regs[value_regno].type = PTR_TO_PACKET; + else if (off == offsetof(struct __sk_buff, data_end) && + env->allow_ptr_leaks) + state->regs[value_regno].type = PTR_TO_PACKET_END; + } - } else if (state->regs[regno].type == FRAME_PTR || - state->regs[regno].type == PTR_TO_STACK) { + } else if (reg->type == FRAME_PTR || reg->type == PTR_TO_STACK) { if (off >= 0 || off < -MAX_BPF_STACK) { verbose("invalid stack off=%d size=%d\n", off, size); return -EACCES; @@ -735,11 +835,28 @@ static int check_mem_access(struct verifier_env *env, u32 regno, int off, } else { err = check_stack_read(state, off, size, value_regno); } + } else if (state->regs[regno].type == PTR_TO_PACKET) { + if (t == BPF_WRITE) { + verbose("cannot write into packet\n"); + return -EACCES; + } + err = check_packet_access(env, regno, off, size); + if (!err && t == BPF_READ && value_regno >= 0) + mark_reg_unknown_value(state->regs, value_regno); } else { verbose("R%d invalid mem access '%s'\n", - regno, reg_type_str[state->regs[regno].type]); + regno, reg_type_str[reg->type]); return -EACCES; } + + if (!err && size <= 2 && value_regno >= 0 && env->allow_ptr_leaks && + state->regs[value_regno].type == UNKNOWN_VALUE) { + /* 1 or 2 byte load zero-extends, determine the number of + * zero upper bits. Not doing it fo 4 byte load, since + * such values cannot be added to ptr_to_packet anyway. + */ + state->regs[value_regno].imm = 64 - size * 8; + } return err; } @@ -780,7 +897,8 @@ static int check_xadd(struct verifier_env *env, struct bpf_insn *insn) * and all elements of stack are initialized */ static int check_stack_boundary(struct verifier_env *env, int regno, - int access_size, bool zero_size_allowed) + int access_size, bool zero_size_allowed, + struct bpf_call_arg_meta *meta) { struct verifier_state *state = &env->cur_state; struct reg_state *regs = state->regs; @@ -806,6 +924,12 @@ static int check_stack_boundary(struct verifier_env *env, int regno, return -EACCES; } + if (meta && meta->raw_mode) { + meta->access_size = access_size; + meta->regno = regno; + return 0; + } + for (i = 0; i < access_size; i++) { if (state->stack_slot_type[MAX_BPF_STACK + off + i] != STACK_MISC) { verbose("invalid indirect read from stack off %d+%d size %d\n", @@ -817,7 +941,8 @@ static int check_stack_boundary(struct verifier_env *env, int regno, } static int check_func_arg(struct verifier_env *env, u32 regno, - enum bpf_arg_type arg_type, struct bpf_map **mapp) + enum bpf_arg_type arg_type, + struct bpf_call_arg_meta *meta) { struct reg_state *reg = env->cur_state.regs + regno; enum bpf_reg_type expected_type; @@ -849,7 +974,8 @@ static int check_func_arg(struct verifier_env *env, u32 regno, expected_type = CONST_PTR_TO_MAP; } else if (arg_type == ARG_PTR_TO_CTX) { expected_type = PTR_TO_CTX; - } else if (arg_type == ARG_PTR_TO_STACK) { + } else if (arg_type == ARG_PTR_TO_STACK || + arg_type == ARG_PTR_TO_RAW_STACK) { expected_type = PTR_TO_STACK; /* One exception here. In case function allows for NULL to be * passed in as argument, it's a CONST_IMM type. Final test @@ -857,6 +983,7 @@ static int check_func_arg(struct verifier_env *env, u32 regno, */ if (reg->type == CONST_IMM && reg->imm == 0) expected_type = CONST_IMM; + meta->raw_mode = arg_type == ARG_PTR_TO_RAW_STACK; } else { verbose("unsupported arg_type %d\n", arg_type); return -EFAULT; @@ -870,14 +997,13 @@ static int check_func_arg(struct verifier_env *env, u32 regno, if (arg_type == ARG_CONST_MAP_PTR) { /* bpf_map_xxx(map_ptr) call: remember that map_ptr */ - *mapp = reg->map_ptr; - + meta->map_ptr = reg->map_ptr; } else if (arg_type == ARG_PTR_TO_MAP_KEY) { /* bpf_map_xxx(..., map_ptr, ..., key) call: * check that [key, key + map->key_size) are within * stack limits and initialized */ - if (!*mapp) { + if (!meta->map_ptr) { /* in function declaration map_ptr must come before * map_key, so that it's verified and known before * we have to check map_key here. Otherwise it means @@ -886,19 +1012,20 @@ static int check_func_arg(struct verifier_env *env, u32 regno, verbose("invalid map_ptr to access map->key\n"); return -EACCES; } - err = check_stack_boundary(env, regno, (*mapp)->key_size, - false); + err = check_stack_boundary(env, regno, meta->map_ptr->key_size, + false, NULL); } else if (arg_type == ARG_PTR_TO_MAP_VALUE) { /* bpf_map_xxx(..., map_ptr, ..., value) call: * check [value, value + map->value_size) validity */ - if (!*mapp) { + if (!meta->map_ptr) { /* kernel subsystem misconfigured verifier */ verbose("invalid map_ptr to access map->value\n"); return -EACCES; } - err = check_stack_boundary(env, regno, (*mapp)->value_size, - false); + err = check_stack_boundary(env, regno, + meta->map_ptr->value_size, + false, NULL); } else if (arg_type == ARG_CONST_STACK_SIZE || arg_type == ARG_CONST_STACK_SIZE_OR_ZERO) { bool zero_size_allowed = (arg_type == ARG_CONST_STACK_SIZE_OR_ZERO); @@ -913,7 +1040,7 @@ static int check_func_arg(struct verifier_env *env, u32 regno, return -EACCES; } err = check_stack_boundary(env, regno - 1, reg->imm, - zero_size_allowed); + zero_size_allowed, meta); } return err; @@ -921,27 +1048,93 @@ static int check_func_arg(struct verifier_env *env, u32 regno, static int check_map_func_compatibility(struct bpf_map *map, int func_id) { - bool bool_map, bool_func; - int i; - if (!map) return 0; - for (i = 0; i < ARRAY_SIZE(func_limit); i++) { - bool_map = (map->map_type == func_limit[i].map_type); - bool_func = (func_id == func_limit[i].func_id); - /* only when map & func pair match it can continue. - * don't allow any other map type to be passed into - * the special func; - */ - if (bool_func && bool_map != bool_func) { - verbose("cannot pass map_type %d into func %d\n", - map->map_type, func_id); - return -EINVAL; - } + /* We need a two way check, first is from map perspective ... */ + switch (map->map_type) { + case BPF_MAP_TYPE_PROG_ARRAY: + if (func_id != BPF_FUNC_tail_call) + goto error; + break; + case BPF_MAP_TYPE_PERF_EVENT_ARRAY: + if (func_id != BPF_FUNC_perf_event_read && + func_id != BPF_FUNC_perf_event_output) + goto error; + break; + case BPF_MAP_TYPE_STACK_TRACE: + if (func_id != BPF_FUNC_get_stackid) + goto error; + break; + default: + break; + } + + /* ... and second from the function itself. */ + switch (func_id) { + case BPF_FUNC_tail_call: + if (map->map_type != BPF_MAP_TYPE_PROG_ARRAY) + goto error; + break; + case BPF_FUNC_perf_event_read: + case BPF_FUNC_perf_event_output: + if (map->map_type != BPF_MAP_TYPE_PERF_EVENT_ARRAY) + goto error; + break; + case BPF_FUNC_get_stackid: + if (map->map_type != BPF_MAP_TYPE_STACK_TRACE) + goto error; + break; + default: + break; } return 0; +error: + verbose("cannot pass map_type %d into func %d\n", + map->map_type, func_id); + return -EINVAL; +} + +static int check_raw_mode(const struct bpf_func_proto *fn) +{ + int count = 0; + + if (fn->arg1_type == ARG_PTR_TO_RAW_STACK) + count++; + if (fn->arg2_type == ARG_PTR_TO_RAW_STACK) + count++; + if (fn->arg3_type == ARG_PTR_TO_RAW_STACK) + count++; + if (fn->arg4_type == ARG_PTR_TO_RAW_STACK) + count++; + if (fn->arg5_type == ARG_PTR_TO_RAW_STACK) + count++; + + return count > 1 ? -EINVAL : 0; +} + +static void clear_all_pkt_pointers(struct verifier_env *env) +{ + struct verifier_state *state = &env->cur_state; + struct reg_state *regs = state->regs, *reg; + int i; + + for (i = 0; i < MAX_BPF_REG; i++) + if (regs[i].type == PTR_TO_PACKET || + regs[i].type == PTR_TO_PACKET_END) + mark_reg_unknown_value(regs, i); + + for (i = 0; i < MAX_BPF_STACK; i += BPF_REG_SIZE) { + if (state->stack_slot_type[i] != STACK_SPILL) + continue; + reg = &state->spilled_regs[i / BPF_REG_SIZE]; + if (reg->type != PTR_TO_PACKET && + reg->type != PTR_TO_PACKET_END) + continue; + reg->type = UNKNOWN_VALUE; + reg->imm = 0; + } } static int check_call(struct verifier_env *env, int func_id) @@ -949,8 +1142,9 @@ static int check_call(struct verifier_env *env, int func_id) struct verifier_state *state = &env->cur_state; const struct bpf_func_proto *fn = NULL; struct reg_state *regs = state->regs; - struct bpf_map *map = NULL; struct reg_state *reg; + struct bpf_call_arg_meta meta; + bool changes_data; int i, err; /* find function prototype */ @@ -973,23 +1167,45 @@ static int check_call(struct verifier_env *env, int func_id) return -EINVAL; } + changes_data = bpf_helper_changes_skb_data(fn->func); + + memset(&meta, 0, sizeof(meta)); + + /* We only support one arg being in raw mode at the moment, which + * is sufficient for the helper functions we have right now. + */ + err = check_raw_mode(fn); + if (err) { + verbose("kernel subsystem misconfigured func %d\n", func_id); + return err; + } + /* check args */ - err = check_func_arg(env, BPF_REG_1, fn->arg1_type, &map); + err = check_func_arg(env, BPF_REG_1, fn->arg1_type, &meta); if (err) return err; - err = check_func_arg(env, BPF_REG_2, fn->arg2_type, &map); + err = check_func_arg(env, BPF_REG_2, fn->arg2_type, &meta); if (err) return err; - err = check_func_arg(env, BPF_REG_3, fn->arg3_type, &map); + err = check_func_arg(env, BPF_REG_3, fn->arg3_type, &meta); if (err) return err; - err = check_func_arg(env, BPF_REG_4, fn->arg4_type, &map); + err = check_func_arg(env, BPF_REG_4, fn->arg4_type, &meta); if (err) return err; - err = check_func_arg(env, BPF_REG_5, fn->arg5_type, &map); + err = check_func_arg(env, BPF_REG_5, fn->arg5_type, &meta); if (err) return err; + /* Mark slots with STACK_MISC in case of raw mode, stack offset + * is inferred from register state. + */ + for (i = 0; i < meta.access_size; i++) { + err = check_mem_access(env, meta.regno, i, BPF_B, BPF_WRITE, -1); + if (err) + return err; + } + /* reset caller saved regs */ for (i = 0; i < CALLER_SAVED_REGS; i++) { reg = regs + caller_saved[i]; @@ -1008,28 +1224,211 @@ static int check_call(struct verifier_env *env, int func_id) * can check 'value_size' boundary of memory access * to map element returned from bpf_map_lookup_elem() */ - if (map == NULL) { + if (meta.map_ptr == NULL) { verbose("kernel subsystem misconfigured verifier\n"); return -EINVAL; } - regs[BPF_REG_0].map_ptr = map; + regs[BPF_REG_0].map_ptr = meta.map_ptr; } else { verbose("unknown return type %d of func %d\n", fn->ret_type, func_id); return -EINVAL; } - err = check_map_func_compatibility(map, func_id); + err = check_map_func_compatibility(meta.map_ptr, func_id); if (err) return err; + if (changes_data) + clear_all_pkt_pointers(env); + return 0; +} + +static int check_packet_ptr_add(struct verifier_env *env, struct bpf_insn *insn) +{ + struct reg_state *regs = env->cur_state.regs; + struct reg_state *dst_reg = ®s[insn->dst_reg]; + struct reg_state *src_reg = ®s[insn->src_reg]; + s32 imm; + + if (BPF_SRC(insn->code) == BPF_K) { + /* pkt_ptr += imm */ + imm = insn->imm; + +add_imm: + if (imm <= 0) { + verbose("addition of negative constant to packet pointer is not allowed\n"); + return -EACCES; + } + if (imm >= MAX_PACKET_OFF || + imm + dst_reg->off >= MAX_PACKET_OFF) { + verbose("constant %d is too large to add to packet pointer\n", + imm); + return -EACCES; + } + /* a constant was added to pkt_ptr. + * Remember it while keeping the same 'id' + */ + dst_reg->off += imm; + } else { + if (src_reg->type == CONST_IMM) { + /* pkt_ptr += reg where reg is known constant */ + imm = src_reg->imm; + goto add_imm; + } + /* disallow pkt_ptr += reg + * if reg is not uknown_value with guaranteed zero upper bits + * otherwise pkt_ptr may overflow and addition will become + * subtraction which is not allowed + */ + if (src_reg->type != UNKNOWN_VALUE) { + verbose("cannot add '%s' to ptr_to_packet\n", + reg_type_str[src_reg->type]); + return -EACCES; + } + if (src_reg->imm < 48) { + verbose("cannot add integer value with %lld upper zero bits to ptr_to_packet\n", + src_reg->imm); + return -EACCES; + } + /* dst_reg stays as pkt_ptr type and since some positive + * integer value was added to the pointer, increment its 'id' + */ + dst_reg->id++; + + /* something was added to pkt_ptr, set range and off to zero */ + dst_reg->off = 0; + dst_reg->range = 0; + } + return 0; +} + +static int evaluate_reg_alu(struct verifier_env *env, struct bpf_insn *insn) +{ + struct reg_state *regs = env->cur_state.regs; + struct reg_state *dst_reg = ®s[insn->dst_reg]; + u8 opcode = BPF_OP(insn->code); + s64 imm_log2; + + /* for type == UNKNOWN_VALUE: + * imm > 0 -> number of zero upper bits + * imm == 0 -> don't track which is the same as all bits can be non-zero + */ + + if (BPF_SRC(insn->code) == BPF_X) { + struct reg_state *src_reg = ®s[insn->src_reg]; + + if (src_reg->type == UNKNOWN_VALUE && src_reg->imm > 0 && + dst_reg->imm && opcode == BPF_ADD) { + /* dreg += sreg + * where both have zero upper bits. Adding them + * can only result making one more bit non-zero + * in the larger value. + * Ex. 0xffff (imm=48) + 1 (imm=63) = 0x10000 (imm=47) + * 0xffff (imm=48) + 0xffff = 0x1fffe (imm=47) + */ + dst_reg->imm = min(dst_reg->imm, src_reg->imm); + dst_reg->imm--; + return 0; + } + if (src_reg->type == CONST_IMM && src_reg->imm > 0 && + dst_reg->imm && opcode == BPF_ADD) { + /* dreg += sreg + * where dreg has zero upper bits and sreg is const. + * Adding them can only result making one more bit + * non-zero in the larger value. + */ + imm_log2 = __ilog2_u64((long long)src_reg->imm); + dst_reg->imm = min(dst_reg->imm, 63 - imm_log2); + dst_reg->imm--; + return 0; + } + /* all other cases non supported yet, just mark dst_reg */ + dst_reg->imm = 0; + return 0; + } + + /* sign extend 32-bit imm into 64-bit to make sure that + * negative values occupy bit 63. Note ilog2() would have + * been incorrect, since sizeof(insn->imm) == 4 + */ + imm_log2 = __ilog2_u64((long long)insn->imm); + + if (dst_reg->imm && opcode == BPF_LSH) { + /* reg <<= imm + * if reg was a result of 2 byte load, then its imm == 48 + * which means that upper 48 bits are zero and shifting this reg + * left by 4 would mean that upper 44 bits are still zero + */ + dst_reg->imm -= insn->imm; + } else if (dst_reg->imm && opcode == BPF_MUL) { + /* reg *= imm + * if multiplying by 14 subtract 4 + * This is conservative calculation of upper zero bits. + * It's not trying to special case insn->imm == 1 or 0 cases + */ + dst_reg->imm -= imm_log2 + 1; + } else if (opcode == BPF_AND) { + /* reg &= imm */ + dst_reg->imm = 63 - imm_log2; + } else if (dst_reg->imm && opcode == BPF_ADD) { + /* reg += imm */ + dst_reg->imm = min(dst_reg->imm, 63 - imm_log2); + dst_reg->imm--; + } else if (opcode == BPF_RSH) { + /* reg >>= imm + * which means that after right shift, upper bits will be zero + * note that verifier already checked that + * 0 <= imm < 64 for shift insn + */ + dst_reg->imm += insn->imm; + if (unlikely(dst_reg->imm > 64)) + /* some dumb code did: + * r2 = *(u32 *)mem; + * r2 >>= 32; + * and all bits are zero now */ + dst_reg->imm = 64; + } else { + /* all other alu ops, means that we don't know what will + * happen to the value, mark it with unknown number of zero bits + */ + dst_reg->imm = 0; + } + + if (dst_reg->imm < 0) { + /* all 64 bits of the register can contain non-zero bits + * and such value cannot be added to ptr_to_packet, since it + * may overflow, mark it as unknown to avoid further eval + */ + dst_reg->imm = 0; + } + return 0; +} + +static int evaluate_reg_imm_alu(struct verifier_env *env, struct bpf_insn *insn) +{ + struct reg_state *regs = env->cur_state.regs; + struct reg_state *dst_reg = ®s[insn->dst_reg]; + struct reg_state *src_reg = ®s[insn->src_reg]; + u8 opcode = BPF_OP(insn->code); + + /* dst_reg->type == CONST_IMM here, simulate execution of 'add' insn. + * Don't care about overflow or negative values, just add them + */ + if (opcode == BPF_ADD && BPF_SRC(insn->code) == BPF_K) + dst_reg->imm += insn->imm; + else if (opcode == BPF_ADD && BPF_SRC(insn->code) == BPF_X && + src_reg->type == CONST_IMM) + dst_reg->imm += src_reg->imm; + else + mark_reg_unknown_value(regs, insn->dst_reg); return 0; } /* check validity of 32-bit and 64-bit arithmetic operations */ static int check_alu_op(struct verifier_env *env, struct bpf_insn *insn) { - struct reg_state *regs = env->cur_state.regs; + struct reg_state *regs = env->cur_state.regs, *dst_reg; u8 opcode = BPF_OP(insn->code); int err; @@ -1118,8 +1517,6 @@ static int check_alu_op(struct verifier_env *env, struct bpf_insn *insn) } else { /* all other ALU ops: and, sub, xor, add, ... */ - bool stack_relative = false; - if (BPF_SRC(insn->code) == BPF_X) { if (insn->imm != 0 || insn->off != 0) { verbose("BPF_ALU uses reserved fields\n"); @@ -1157,11 +1554,34 @@ static int check_alu_op(struct verifier_env *env, struct bpf_insn *insn) } } + /* check dest operand */ + err = check_reg_arg(regs, insn->dst_reg, DST_OP_NO_MARK); + if (err) + return err; + + dst_reg = ®s[insn->dst_reg]; + /* pattern match 'bpf_add Rx, imm' instruction */ if (opcode == BPF_ADD && BPF_CLASS(insn->code) == BPF_ALU64 && - regs[insn->dst_reg].type == FRAME_PTR && - BPF_SRC(insn->code) == BPF_K) { - stack_relative = true; + dst_reg->type == FRAME_PTR && BPF_SRC(insn->code) == BPF_K) { + dst_reg->type = PTR_TO_STACK; + dst_reg->imm = insn->imm; + return 0; + } else if (opcode == BPF_ADD && + BPF_CLASS(insn->code) == BPF_ALU64 && + dst_reg->type == PTR_TO_PACKET) { + /* ptr_to_packet += K|X */ + return check_packet_ptr_add(env, insn); + } else if (BPF_CLASS(insn->code) == BPF_ALU64 && + dst_reg->type == UNKNOWN_VALUE && + env->allow_ptr_leaks) { + /* unknown += K|X */ + return evaluate_reg_alu(env, insn); + } else if (BPF_CLASS(insn->code) == BPF_ALU64 && + dst_reg->type == CONST_IMM && + env->allow_ptr_leaks) { + /* reg_imm += K|X */ + return evaluate_reg_imm_alu(env, insn); } else if (is_pointer_value(env, insn->dst_reg)) { verbose("R%d pointer arithmetic prohibited\n", insn->dst_reg); @@ -1173,24 +1593,45 @@ static int check_alu_op(struct verifier_env *env, struct bpf_insn *insn) return -EACCES; } - /* check dest operand */ - err = check_reg_arg(regs, insn->dst_reg, DST_OP); - if (err) - return err; - - if (stack_relative) { - regs[insn->dst_reg].type = PTR_TO_STACK; - regs[insn->dst_reg].imm = insn->imm; - } + /* mark dest operand */ + mark_reg_unknown_value(regs, insn->dst_reg); } return 0; } +static void find_good_pkt_pointers(struct verifier_env *env, + struct reg_state *dst_reg) +{ + struct verifier_state *state = &env->cur_state; + struct reg_state *regs = state->regs, *reg; + int i; + /* r2 = r3; + * r2 += 8 + * if (r2 > pkt_end) goto somewhere + * r2 == dst_reg, pkt_end == src_reg, + * r2=pkt(id=n,off=8,r=0) + * r3=pkt(id=n,off=0,r=0) + * find register r3 and mark its range as r3=pkt(id=n,off=0,r=8) + * so that range of bytes [r3, r3 + 8) is safe to access + */ + for (i = 0; i < MAX_BPF_REG; i++) + if (regs[i].type == PTR_TO_PACKET && regs[i].id == dst_reg->id) + regs[i].range = dst_reg->off; + + for (i = 0; i < MAX_BPF_STACK; i += BPF_REG_SIZE) { + if (state->stack_slot_type[i] != STACK_SPILL) + continue; + reg = &state->spilled_regs[i / BPF_REG_SIZE]; + if (reg->type == PTR_TO_PACKET && reg->id == dst_reg->id) + reg->range = dst_reg->off; + } +} + static int check_cond_jmp_op(struct verifier_env *env, struct bpf_insn *insn, int *insn_idx) { - struct reg_state *regs = env->cur_state.regs; + struct reg_state *regs = env->cur_state.regs, *dst_reg; struct verifier_state *other_branch; u8 opcode = BPF_OP(insn->code); int err; @@ -1228,11 +1669,12 @@ static int check_cond_jmp_op(struct verifier_env *env, if (err) return err; + dst_reg = ®s[insn->dst_reg]; + /* detect if R == 0 where R was initialized to zero earlier */ if (BPF_SRC(insn->code) == BPF_K && (opcode == BPF_JEQ || opcode == BPF_JNE) && - regs[insn->dst_reg].type == CONST_IMM && - regs[insn->dst_reg].imm == insn->imm) { + dst_reg->type == CONST_IMM && dst_reg->imm == insn->imm) { if (opcode == BPF_JEQ) { /* if (imm == imm) goto pc+off; * only follow the goto, ignore fall-through @@ -1254,44 +1696,30 @@ static int check_cond_jmp_op(struct verifier_env *env, /* detect if R == 0 where R is returned value from bpf_map_lookup_elem() */ if (BPF_SRC(insn->code) == BPF_K && - insn->imm == 0 && (opcode == BPF_JEQ || - opcode == BPF_JNE) && - regs[insn->dst_reg].type == PTR_TO_MAP_VALUE_OR_NULL) { + insn->imm == 0 && (opcode == BPF_JEQ || opcode == BPF_JNE) && + dst_reg->type == PTR_TO_MAP_VALUE_OR_NULL) { if (opcode == BPF_JEQ) { /* next fallthrough insn can access memory via * this register */ regs[insn->dst_reg].type = PTR_TO_MAP_VALUE; /* branch targer cannot access it, since reg == 0 */ - other_branch->regs[insn->dst_reg].type = CONST_IMM; - other_branch->regs[insn->dst_reg].imm = 0; + mark_reg_unknown_value(other_branch->regs, + insn->dst_reg); } else { other_branch->regs[insn->dst_reg].type = PTR_TO_MAP_VALUE; - regs[insn->dst_reg].type = CONST_IMM; - regs[insn->dst_reg].imm = 0; + mark_reg_unknown_value(regs, insn->dst_reg); } + } else if (BPF_SRC(insn->code) == BPF_X && opcode == BPF_JGT && + dst_reg->type == PTR_TO_PACKET && + regs[insn->src_reg].type == PTR_TO_PACKET_END) { + find_good_pkt_pointers(env, dst_reg); } else if (is_pointer_value(env, insn->dst_reg)) { verbose("R%d pointer comparison prohibited\n", insn->dst_reg); return -EACCES; - } else if (BPF_SRC(insn->code) == BPF_K && - (opcode == BPF_JEQ || opcode == BPF_JNE)) { - - if (opcode == BPF_JEQ) { - /* detect if (R == imm) goto - * and in the target state recognize that R = imm - */ - other_branch->regs[insn->dst_reg].type = CONST_IMM; - other_branch->regs[insn->dst_reg].imm = insn->imm; - } else { - /* detect if (R != imm) goto - * and in the fall-through state recognize that R = imm - */ - regs[insn->dst_reg].type = CONST_IMM; - regs[insn->dst_reg].imm = insn->imm; - } } if (log_level) - print_verifier_state(env); + print_verifier_state(&env->cur_state); return 0; } @@ -1369,13 +1797,14 @@ static int check_ld_abs(struct verifier_env *env, struct bpf_insn *insn) int i, err; if (!may_access_skb(env->prog->type)) { - verbose("BPF_LD_ABS|IND instructions not allowed for this program type\n"); + verbose("BPF_LD_[ABS|IND] instructions not allowed for this program type\n"); return -EINVAL; } if (insn->dst_reg != BPF_REG_0 || insn->off != 0 || + BPF_SIZE(insn->code) == BPF_DW || (mode == BPF_ABS && insn->src_reg != BPF_REG_0)) { - verbose("BPF_LD_ABS uses reserved fields\n"); + verbose("BPF_LD_[ABS|IND] uses reserved fields\n"); return -EINVAL; } @@ -1539,6 +1968,8 @@ peek_stack: goto peek_stack; else if (ret < 0) goto err_free; + if (t + 1 < insn_cnt) + env->explored_states[t + 1] = STATE_LIST_MARK; } else if (opcode == BPF_JA) { if (BPF_SRC(insns[t].code) != BPF_K) { ret = -EINVAL; @@ -1606,6 +2037,58 @@ err_free: return ret; } +/* the following conditions reduce the number of explored insns + * from ~140k to ~80k for ultra large programs that use a lot of ptr_to_packet + */ +static bool compare_ptrs_to_packet(struct reg_state *old, struct reg_state *cur) +{ + if (old->id != cur->id) + return false; + + /* old ptr_to_packet is more conservative, since it allows smaller + * range. Ex: + * old(off=0,r=10) is equal to cur(off=0,r=20), because + * old(off=0,r=10) means that with range=10 the verifier proceeded + * further and found no issues with the program. Now we're in the same + * spot with cur(off=0,r=20), so we're safe too, since anything further + * will only be looking at most 10 bytes after this pointer. + */ + if (old->off == cur->off && old->range < cur->range) + return true; + + /* old(off=20,r=10) is equal to cur(off=22,re=22 or 5 or 0) + * since both cannot be used for packet access and safe(old) + * pointer has smaller off that could be used for further + * 'if (ptr > data_end)' check + * Ex: + * old(off=20,r=10) and cur(off=22,r=22) and cur(off=22,r=0) mean + * that we cannot access the packet. + * The safe range is: + * [ptr, ptr + range - off) + * so whenever off >=range, it means no safe bytes from this pointer. + * When comparing old->off <= cur->off, it means that older code + * went with smaller offset and that offset was later + * used to figure out the safe range after 'if (ptr > data_end)' check + * Say, 'old' state was explored like: + * ... R3(off=0, r=0) + * R4 = R3 + 20 + * ... now R4(off=20,r=0) <-- here + * if (R4 > data_end) + * ... R4(off=20,r=20), R3(off=0,r=20) and R3 can be used to access. + * ... the code further went all the way to bpf_exit. + * Now the 'cur' state at the mark 'here' has R4(off=30,r=0). + * old_R4(off=20,r=0) equal to cur_R4(off=30,r=0), since if the verifier + * goes further, such cur_R4 will give larger safe packet range after + * 'if (R4 > data_end)' and all further insn were already good with r=20, + * so they will be good with r=30 and we can prune the search. + */ + if (old->off <= cur->off && + old->off >= old->range && cur->off >= cur->range) + return true; + + return false; +} + /* compare two verifier states * * all states stored in state_list are known to be valid, since @@ -1634,17 +2117,25 @@ err_free: */ static bool states_equal(struct verifier_state *old, struct verifier_state *cur) { + struct reg_state *rold, *rcur; int i; for (i = 0; i < MAX_BPF_REG; i++) { - if (memcmp(&old->regs[i], &cur->regs[i], - sizeof(old->regs[0])) != 0) { - if (old->regs[i].type == NOT_INIT || - (old->regs[i].type == UNKNOWN_VALUE && - cur->regs[i].type != NOT_INIT)) - continue; - return false; - } + rold = &old->regs[i]; + rcur = &cur->regs[i]; + + if (memcmp(rold, rcur, sizeof(*rold)) == 0) + continue; + + if (rold->type == NOT_INIT || + (rold->type == UNKNOWN_VALUE && rcur->type != NOT_INIT)) + continue; + + if (rold->type == PTR_TO_PACKET && rcur->type == PTR_TO_PACKET && + compare_ptrs_to_packet(rold, rcur)) + continue; + + return false; } for (i = 0; i < MAX_BPF_STACK; i++) { @@ -1743,7 +2234,7 @@ static int do_check(struct verifier_env *env) insn = &insns[insn_idx]; class = BPF_CLASS(insn->code); - if (++insn_processed > 32768) { + if (++insn_processed > BPF_COMPLEXITY_LIMIT_INSNS) { verbose("BPF program is too large. Proccessed %d insn\n", insn_processed); return -E2BIG; @@ -1766,7 +2257,7 @@ static int do_check(struct verifier_env *env) if (log_level && do_print_state) { verbose("\nfrom %d to %d:", prev_insn_idx, insn_idx); - print_verifier_state(env); + print_verifier_state(&env->cur_state); do_print_state = false; } @@ -1978,6 +2469,7 @@ process_bpf_exit: insn_idx++; } + verbose("processed %d insns\n", insn_processed); return 0; } @@ -2029,7 +2521,6 @@ static int replace_map_fd_with_map_ptr(struct verifier_env *env) if (IS_ERR(map)) { verbose("fd %d is not pointing to valid bpf_map\n", insn->imm); - fdput(f); return PTR_ERR(map); } @@ -2049,15 +2540,18 @@ static int replace_map_fd_with_map_ptr(struct verifier_env *env) return -E2BIG; } - /* remember this map */ - env->used_maps[env->used_map_cnt++] = map; - /* hold the map. If the program is rejected by verifier, * the map will be released by release_maps() or it * will be used by the valid program until it's unloaded * and all maps are released in free_bpf_prog_info() */ - bpf_map_inc(map, false); + map = bpf_map_inc(map, false); + if (IS_ERR(map)) { + fdput(f); + return PTR_ERR(map); + } + env->used_maps[env->used_map_cnt++] = map; + fdput(f); next_insn: insn++; @@ -2093,26 +2587,6 @@ static void convert_pseudo_ld_imm64(struct verifier_env *env) insn->src_reg = 0; } -static void adjust_branches(struct bpf_prog *prog, int pos, int delta) -{ - struct bpf_insn *insn = prog->insnsi; - int insn_cnt = prog->len; - int i; - - for (i = 0; i < insn_cnt; i++, insn++) { - if (BPF_CLASS(insn->code) != BPF_JMP || - BPF_OP(insn->code) == BPF_CALL || - BPF_OP(insn->code) == BPF_EXIT) - continue; - - /* adjust offset of jmps if necessary */ - if (i < pos && i + insn->off + 1 > pos) - insn->off += delta; - else if (i > pos + delta && i + insn->off + 1 <= pos + delta) - insn->off -= delta; - } -} - /* convert load instructions that access fields of 'struct __sk_buff' * into sequence of instructions that access fields of 'struct sk_buff' */ @@ -2122,14 +2596,15 @@ static int convert_ctx_accesses(struct verifier_env *env) int insn_cnt = env->prog->len; struct bpf_insn insn_buf[16]; struct bpf_prog *new_prog; - u32 cnt; - int i; enum bpf_access_type type; + int i; if (!env->prog->aux->ops->convert_ctx_access) return 0; for (i = 0; i < insn_cnt; i++, insn++) { + u32 insn_delta, cnt; + if (insn->code == (BPF_LDX | BPF_MEM | BPF_W)) type = BPF_READ; else if (insn->code == (BPF_STX | BPF_MEM | BPF_W)) @@ -2151,34 +2626,18 @@ static int convert_ctx_accesses(struct verifier_env *env) return -EINVAL; } - if (cnt == 1) { - memcpy(insn, insn_buf, sizeof(*insn)); - continue; - } - - /* several new insns need to be inserted. Make room for them */ - insn_cnt += cnt - 1; - new_prog = bpf_prog_realloc(env->prog, - bpf_prog_size(insn_cnt), - GFP_USER); + new_prog = bpf_patch_insn_single(env->prog, i, insn_buf, cnt); if (!new_prog) return -ENOMEM; - new_prog->len = insn_cnt; - - memmove(new_prog->insnsi + i + cnt, new_prog->insns + i + 1, - sizeof(*insn) * (insn_cnt - i - cnt)); - - /* copy substitute insns in place of load instruction */ - memcpy(new_prog->insnsi + i, insn_buf, sizeof(*insn) * cnt); - - /* adjust branches in the whole program */ - adjust_branches(new_prog, i, cnt - 1); + insn_delta = cnt - 1; /* keep walking new program and skip insns we just inserted */ env->prog = new_prog; - insn = new_prog->insnsi + i + cnt - 1; - i += cnt - 1; + insn = new_prog->insnsi + i + insn_delta; + + insn_cnt += insn_delta; + i += insn_delta; } return 0; diff --git a/kernel/cgroup.c b/kernel/cgroup.c index 671dc05c0b0f..86cb5c6e8932 100644 --- a/kernel/cgroup.c +++ b/kernel/cgroup.c @@ -1215,6 +1215,41 @@ static void cgroup_destroy_root(struct cgroup_root *root) cgroup_free_root(root); } +/* + * look up cgroup associated with current task's cgroup namespace on the + * specified hierarchy + */ +static struct cgroup * +current_cgns_cgroup_from_root(struct cgroup_root *root) +{ + struct cgroup *res = NULL; + struct css_set *cset; + + lockdep_assert_held(&css_set_lock); + + rcu_read_lock(); + + cset = current->nsproxy->cgroup_ns->root_cset; + if (cset == &init_css_set) { + res = &root->cgrp; + } else { + struct cgrp_cset_link *link; + + list_for_each_entry(link, &cset->cgrp_links, cgrp_link) { + struct cgroup *c = link->cgrp; + + if (c->root == root) { + res = c; + break; + } + } + } + rcu_read_unlock(); + + BUG_ON(!res); + return res; +} + /* look up cgroup associated with given css_set on the specified hierarchy */ static struct cgroup *cset_cgroup_from_root(struct css_set *cset, struct cgroup_root *root) @@ -1593,6 +1628,33 @@ static int rebind_subsystems(struct cgroup_root *dst_root, u16 ss_mask) return 0; } +static int cgroup_show_path(struct seq_file *sf, struct kernfs_node *kf_node, + struct kernfs_root *kf_root) +{ + int len = 0; + char *buf = NULL; + struct cgroup_root *kf_cgroot = cgroup_root_from_kf(kf_root); + struct cgroup *ns_cgroup; + + buf = kmalloc(PATH_MAX, GFP_KERNEL); + if (!buf) + return -ENOMEM; + + spin_lock_bh(&css_set_lock); + ns_cgroup = current_cgns_cgroup_from_root(kf_cgroot); + len = kernfs_path_from_node(kf_node, ns_cgroup->kn, buf, PATH_MAX); + spin_unlock_bh(&css_set_lock); + + if (len >= PATH_MAX) + len = -ERANGE; + else if (len > 0) { + seq_escape(sf, buf, " \t\n\\"); + len = 0; + } + kfree(buf); + return len; +} + static int cgroup_show_options(struct seq_file *seq, struct kernfs_root *kf_root) { @@ -2825,9 +2887,10 @@ static ssize_t __cgroup_procs_write(struct kernfs_open_file *of, char *buf, size_t nbytes, loff_t off, bool threadgroup) { struct task_struct *tsk; + struct cgroup_subsys *ss; struct cgroup *cgrp; pid_t pid; - int ret; + int ssid, ret; if (kstrtoint(strstrip(buf), 0, &pid) || pid < 0) return -EINVAL; @@ -2875,8 +2938,10 @@ out_unlock_rcu: rcu_read_unlock(); out_unlock_threadgroup: percpu_up_write(&cgroup_threadgroup_rwsem); + for_each_subsys(ss, ssid) + if (ss->post_attach) + ss->post_attach(); cgroup_kn_unlock(of->kn); - cpuset_post_attach_flush(); return ret ?: nbytes; } @@ -5430,6 +5495,7 @@ static struct kernfs_syscall_ops cgroup_kf_syscall_ops = { .mkdir = cgroup_mkdir, .rmdir = cgroup_rmdir, .rename = cgroup_rename, + .show_path = cgroup_show_path, }; static void __init cgroup_init_subsys(struct cgroup_subsys *ss, bool early) diff --git a/kernel/cpu.c b/kernel/cpu.c index 6ea42e8da861..d948e44c471e 100644 --- a/kernel/cpu.c +++ b/kernel/cpu.c @@ -36,6 +36,7 @@ * @target: The target state * @thread: Pointer to the hotplug thread * @should_run: Thread should execute + * @rollback: Perform a rollback * @cb_stat: The state for a single callback (install/uninstall) * @cb: Single callback function (install/uninstall) * @result: Result of the operation @@ -47,6 +48,7 @@ struct cpuhp_cpu_state { #ifdef CONFIG_SMP struct task_struct *thread; bool should_run; + bool rollback; enum cpuhp_state cb_state; int (*cb)(unsigned int cpu); int result; @@ -301,6 +303,11 @@ static int cpu_notify(unsigned long val, unsigned int cpu) return __cpu_notify(val, cpu, -1, NULL); } +static void cpu_notify_nofail(unsigned long val, unsigned int cpu) +{ + BUG_ON(cpu_notify(val, cpu)); +} + /* Notifier wrappers for transitioning to state machine */ static int notify_prepare(unsigned int cpu) { @@ -477,6 +484,16 @@ static void cpuhp_thread_fun(unsigned int cpu) } else { ret = cpuhp_invoke_callback(cpu, st->cb_state, st->cb); } + } else if (st->rollback) { + BUG_ON(st->state < CPUHP_AP_ONLINE_IDLE); + + undo_cpu_down(cpu, st, cpuhp_ap_states); + /* + * This is a momentary workaround to keep the notifier users + * happy. Will go away once we got rid of the notifiers. + */ + cpu_notify_nofail(CPU_DOWN_FAILED, cpu); + st->rollback = false; } else { /* Cannot happen .... */ BUG_ON(st->state < CPUHP_AP_ONLINE_IDLE); @@ -636,11 +653,6 @@ static inline void check_for_tasks(int dead_cpu) read_unlock(&tasklist_lock); } -static void cpu_notify_nofail(unsigned long val, unsigned int cpu) -{ - BUG_ON(cpu_notify(val, cpu)); -} - static int notify_down_prepare(unsigned int cpu) { int err, nr_calls = 0; @@ -691,21 +703,6 @@ static int takedown_cpu(unsigned int cpu) struct cpuhp_cpu_state *st = per_cpu_ptr(&cpuhp_state, cpu); int err; - /* - * By now we've cleared cpu_active_mask, wait for all preempt-disabled - * and RCU users of this state to go away such that all new such users - * will observe it. - * - * For CONFIG_PREEMPT we have preemptible RCU and its sync_rcu() might - * not imply sync_sched(), so wait for both. - * - * Do sync before park smpboot threads to take care the rcu boost case. - */ - if (IS_ENABLED(CONFIG_PREEMPT)) - synchronize_rcu_mult(call_rcu, call_rcu_sched); - else - synchronize_rcu(); - /* Park the smpboot threads */ kthread_park(per_cpu_ptr(&cpuhp_state, cpu)->thread); smpboot_park_threads(cpu); @@ -721,9 +718,10 @@ static int takedown_cpu(unsigned int cpu) */ err = stop_machine(take_cpu_down, NULL, cpumask_of(cpu)); if (err) { - /* CPU didn't die: tell everyone. Can't complain. */ - cpu_notify_nofail(CPU_DOWN_FAILED, cpu); + /* CPU refused to die */ irq_unlock_sparse(); + /* Unpark the hotplug thread so we can rollback there */ + kthread_unpark(per_cpu_ptr(&cpuhp_state, cpu)->thread); return err; } BUG_ON(cpu_online(cpu)); @@ -832,6 +830,11 @@ static int __ref _cpu_down(unsigned int cpu, int tasks_frozen, * to do the further cleanups. */ ret = cpuhp_down_callbacks(cpu, st, cpuhp_bp_states, target); + if (ret && st->state > CPUHP_TEARDOWN_CPU && st->state < prev_state) { + st->target = prev_state; + st->rollback = true; + cpuhp_kick_ap_work(cpu); + } hasdied = prev_state != st->state && st->state == CPUHP_OFFLINE; out: @@ -905,8 +908,6 @@ void cpuhp_online_idle(enum cpuhp_state state) st->state = CPUHP_AP_ONLINE_IDLE; - /* The cpu is marked online, set it active now */ - set_cpu_active(cpu, true); /* Unpark the stopper thread and the hotplug thread of this cpu */ stop_machine_unpark(cpu); kthread_unpark(st->thread); @@ -1218,6 +1219,12 @@ static struct cpuhp_step cpuhp_ap_states[] = { .name = "ap:offline", .cant_stop = true, }, + /* First state is scheduler control. Interrupts are disabled */ + [CPUHP_AP_SCHED_STARTING] = { + .name = "sched:starting", + .startup = sched_cpu_starting, + .teardown = sched_cpu_dying, + }, /* * Low level startup/teardown notifiers. Run with interrupts * disabled. Will be removed once the notifiers are converted to @@ -1249,12 +1256,22 @@ static struct cpuhp_step cpuhp_ap_states[] = { .name = "notify:online", .startup = notify_online, .teardown = notify_down_prepare, + .skip_onerr = true, }, #endif /* * The dynamically registered state space is here */ +#ifdef CONFIG_SMP + /* Last state is scheduler control setting the cpu active */ + [CPUHP_AP_ACTIVE] = { + .name = "sched:active", + .startup = sched_cpu_activate, + .teardown = sched_cpu_deactivate, + }, +#endif + /* CPU is fully up and running. */ [CPUHP_ONLINE] = { .name = "online", diff --git a/kernel/cpuset.c b/kernel/cpuset.c index 00ab5c2b7c5b..1902956baba1 100644 --- a/kernel/cpuset.c +++ b/kernel/cpuset.c @@ -58,7 +58,6 @@ #include <asm/uaccess.h> #include <linux/atomic.h> #include <linux/mutex.h> -#include <linux/workqueue.h> #include <linux/cgroup.h> #include <linux/wait.h> @@ -1016,7 +1015,7 @@ static void cpuset_migrate_mm(struct mm_struct *mm, const nodemask_t *from, } } -void cpuset_post_attach_flush(void) +static void cpuset_post_attach(void) { flush_workqueue(cpuset_migrate_mm_wq); } @@ -2087,6 +2086,7 @@ struct cgroup_subsys cpuset_cgrp_subsys = { .can_attach = cpuset_can_attach, .cancel_attach = cpuset_cancel_attach, .attach = cpuset_attach, + .post_attach = cpuset_post_attach, .bind = cpuset_bind, .legacy_cftypes = files, .early_init = true, diff --git a/kernel/events/callchain.c b/kernel/events/callchain.c index 343c22f5e867..b9325e7dcba1 100644 --- a/kernel/events/callchain.c +++ b/kernel/events/callchain.c @@ -18,6 +18,14 @@ struct callchain_cpus_entries { struct perf_callchain_entry *cpu_entries[0]; }; +int sysctl_perf_event_max_stack __read_mostly = PERF_MAX_STACK_DEPTH; + +static inline size_t perf_callchain_entry__sizeof(void) +{ + return (sizeof(struct perf_callchain_entry) + + sizeof(__u64) * sysctl_perf_event_max_stack); +} + static DEFINE_PER_CPU(int, callchain_recursion[PERF_NR_CONTEXTS]); static atomic_t nr_callchain_events; static DEFINE_MUTEX(callchain_mutex); @@ -73,7 +81,7 @@ static int alloc_callchain_buffers(void) if (!entries) return -ENOMEM; - size = sizeof(struct perf_callchain_entry) * PERF_NR_CONTEXTS; + size = perf_callchain_entry__sizeof() * PERF_NR_CONTEXTS; for_each_possible_cpu(cpu) { entries->cpu_entries[cpu] = kmalloc_node(size, GFP_KERNEL, @@ -147,7 +155,8 @@ static struct perf_callchain_entry *get_callchain_entry(int *rctx) cpu = smp_processor_id(); - return &entries->cpu_entries[cpu][*rctx]; + return (((void *)entries->cpu_entries[cpu]) + + (*rctx * perf_callchain_entry__sizeof())); } static void @@ -215,3 +224,25 @@ exit_put: return entry; } + +int perf_event_max_stack_handler(struct ctl_table *table, int write, + void __user *buffer, size_t *lenp, loff_t *ppos) +{ + int new_value = sysctl_perf_event_max_stack, ret; + struct ctl_table new_table = *table; + + new_table.data = &new_value; + ret = proc_dointvec_minmax(&new_table, write, buffer, lenp, ppos); + if (ret || !write) + return ret; + + mutex_lock(&callchain_mutex); + if (atomic_read(&nr_callchain_events)) + ret = -EBUSY; + else + sysctl_perf_event_max_stack = new_value; + + mutex_unlock(&callchain_mutex); + + return ret; +} diff --git a/kernel/events/core.c b/kernel/events/core.c index 52bedc5a5aaa..274450efea90 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -44,6 +44,8 @@ #include <linux/compat.h> #include <linux/bpf.h> #include <linux/filter.h> +#include <linux/namei.h> +#include <linux/parser.h> #include "internal.h" @@ -351,7 +353,7 @@ static struct srcu_struct pmus_srcu; * 1 - disallow cpu events for unpriv * 2 - disallow kernel profiling for unpriv */ -int sysctl_perf_event_paranoid __read_mostly = 1; +int sysctl_perf_event_paranoid __read_mostly = 2; /* Minimum for 512 kiB + 1 user control page */ int sysctl_perf_event_mlock __read_mostly = 512 + (PAGE_SIZE / 1024); /* 'free' kiB per user */ @@ -412,7 +414,8 @@ int perf_cpu_time_max_percent_handler(struct ctl_table *table, int write, if (ret || !write) return ret; - if (sysctl_perf_cpu_time_max_percent == 100) { + if (sysctl_perf_cpu_time_max_percent == 100 || + sysctl_perf_cpu_time_max_percent == 0) { printk(KERN_WARNING "perf: Dynamic interrupt throttling disabled, can hang your system!\n"); WRITE_ONCE(perf_sample_allowed_ns, 0); @@ -1105,6 +1108,7 @@ static void put_ctx(struct perf_event_context *ctx) * function. * * Lock order: + * cred_guard_mutex * task_struct::perf_event_mutex * perf_event_context::mutex * perf_event::child_mutex; @@ -1925,8 +1929,13 @@ event_sched_in(struct perf_event *event, if (event->state <= PERF_EVENT_STATE_OFF) return 0; - event->state = PERF_EVENT_STATE_ACTIVE; - event->oncpu = smp_processor_id(); + WRITE_ONCE(event->oncpu, smp_processor_id()); + /* + * Order event::oncpu write to happen before the ACTIVE state + * is visible. + */ + smp_wmb(); + WRITE_ONCE(event->state, PERF_EVENT_STATE_ACTIVE); /* * Unthrottle events, since we scheduled we might have missed several @@ -2358,6 +2367,112 @@ void perf_event_enable(struct perf_event *event) } EXPORT_SYMBOL_GPL(perf_event_enable); +struct stop_event_data { + struct perf_event *event; + unsigned int restart; +}; + +static int __perf_event_stop(void *info) +{ + struct stop_event_data *sd = info; + struct perf_event *event = sd->event; + + /* if it's already INACTIVE, do nothing */ + if (READ_ONCE(event->state) != PERF_EVENT_STATE_ACTIVE) + return 0; + + /* matches smp_wmb() in event_sched_in() */ + smp_rmb(); + + /* + * There is a window with interrupts enabled before we get here, + * so we need to check again lest we try to stop another CPU's event. + */ + if (READ_ONCE(event->oncpu) != smp_processor_id()) + return -EAGAIN; + + event->pmu->stop(event, PERF_EF_UPDATE); + + /* + * May race with the actual stop (through perf_pmu_output_stop()), + * but it is only used for events with AUX ring buffer, and such + * events will refuse to restart because of rb::aux_mmap_count==0, + * see comments in perf_aux_output_begin(). + * + * Since this is happening on a event-local CPU, no trace is lost + * while restarting. + */ + if (sd->restart) + event->pmu->start(event, PERF_EF_START); + + return 0; +} + +static int perf_event_restart(struct perf_event *event) +{ + struct stop_event_data sd = { + .event = event, + .restart = 1, + }; + int ret = 0; + + do { + if (READ_ONCE(event->state) != PERF_EVENT_STATE_ACTIVE) + return 0; + + /* matches smp_wmb() in event_sched_in() */ + smp_rmb(); + + /* + * We only want to restart ACTIVE events, so if the event goes + * inactive here (event->oncpu==-1), there's nothing more to do; + * fall through with ret==-ENXIO. + */ + ret = cpu_function_call(READ_ONCE(event->oncpu), + __perf_event_stop, &sd); + } while (ret == -EAGAIN); + + return ret; +} + +/* + * In order to contain the amount of racy and tricky in the address filter + * configuration management, it is a two part process: + * + * (p1) when userspace mappings change as a result of (1) or (2) or (3) below, + * we update the addresses of corresponding vmas in + * event::addr_filters_offs array and bump the event::addr_filters_gen; + * (p2) when an event is scheduled in (pmu::add), it calls + * perf_event_addr_filters_sync() which calls pmu::addr_filters_sync() + * if the generation has changed since the previous call. + * + * If (p1) happens while the event is active, we restart it to force (p2). + * + * (1) perf_addr_filters_apply(): adjusting filters' offsets based on + * pre-existing mappings, called once when new filters arrive via SET_FILTER + * ioctl; + * (2) perf_addr_filters_adjust(): adjusting filters' offsets based on newly + * registered mapping, called for every new mmap(), with mm::mmap_sem down + * for reading; + * (3) perf_event_addr_filters_exec(): clearing filters' offsets in the process + * of exec. + */ +void perf_event_addr_filters_sync(struct perf_event *event) +{ + struct perf_addr_filters_head *ifh = perf_event_addr_filters(event); + + if (!has_addr_filter(event)) + return; + + raw_spin_lock(&ifh->lock); + if (event->addr_filters_gen != event->hw.addr_filters_gen) { + event->pmu->addr_filters_sync(event); + event->hw.addr_filters_gen = event->addr_filters_gen; + } + raw_spin_unlock(&ifh->lock); +} +EXPORT_SYMBOL_GPL(perf_event_addr_filters_sync); + static int _perf_event_refresh(struct perf_event *event, int refresh) { /* @@ -3207,16 +3322,6 @@ out: put_ctx(clone_ctx); } -void perf_event_exec(void) -{ - int ctxn; - - rcu_read_lock(); - for_each_task_context_nr(ctxn) - perf_event_enable_on_exec(ctxn); - rcu_read_unlock(); -} - struct perf_read_data { struct perf_event *event; bool group; @@ -3420,7 +3525,6 @@ static struct task_struct * find_lively_task_by_vpid(pid_t vpid) { struct task_struct *task; - int err; rcu_read_lock(); if (!vpid) @@ -3434,16 +3538,7 @@ find_lively_task_by_vpid(pid_t vpid) if (!task) return ERR_PTR(-ESRCH); - /* Reuse ptrace permission checks for now. */ - err = -EACCES; - if (!ptrace_may_access(task, PTRACE_MODE_READ_REALCREDS)) - goto errout; - return task; -errout: - put_task_struct(task); - return ERR_PTR(err); - } /* @@ -3728,6 +3823,9 @@ static bool exclusive_event_installable(struct perf_event *event, return true; } +static void perf_addr_filters_splice(struct perf_event *event, + struct list_head *head); + static void _free_event(struct perf_event *event) { irq_work_sync(&event->pending); @@ -3755,6 +3853,8 @@ static void _free_event(struct perf_event *event) } perf_event_free_bpf_prog(event); + perf_addr_filters_splice(event, NULL); + kfree(event->addr_filters_offs); if (event->destroy) event->destroy(event); @@ -4351,6 +4451,19 @@ static long _perf_ioctl(struct perf_event *event, unsigned int cmd, unsigned lon case PERF_EVENT_IOC_SET_BPF: return perf_event_set_bpf_prog(event, arg); + case PERF_EVENT_IOC_PAUSE_OUTPUT: { + struct ring_buffer *rb; + + rcu_read_lock(); + rb = rcu_dereference(event->rb); + if (!rb || !rb->nr_pages) { + rcu_read_unlock(); + return -EINVAL; + } + rb_toggle_paused(rb, !!arg); + rcu_read_unlock(); + return 0; + } default: return -ENOTTY; } @@ -4667,6 +4780,8 @@ static void perf_mmap_open(struct vm_area_struct *vma) event->pmu->event_mapped(event); } +static void perf_pmu_output_stop(struct perf_event *event); + /* * A buffer can be mmap()ed multiple times; either directly through the same * event, or through other events by use of perf_event_set_output(). @@ -4694,10 +4809,22 @@ static void perf_mmap_close(struct vm_area_struct *vma) */ if (rb_has_aux(rb) && vma->vm_pgoff == rb->aux_pgoff && atomic_dec_and_mutex_lock(&rb->aux_mmap_count, &event->mmap_mutex)) { + /* + * Stop all AUX events that are writing to this buffer, + * so that we can free its AUX pages and corresponding PMU + * data. Note that after rb::aux_mmap_count dropped to zero, + * they won't start any more (see perf_aux_output_begin()). + */ + perf_pmu_output_stop(event); + + /* now it's safe to free the pages */ atomic_long_sub(rb->aux_nr_pages, &mmap_user->locked_vm); vma->vm_mm->pinned_vm -= rb->aux_mmap_locked; + /* this has to be the last one */ rb_free_aux(rb); + WARN_ON_ONCE(atomic_read(&rb->aux_refcount)); + mutex_unlock(&event->mmap_mutex); } @@ -5638,9 +5765,13 @@ void perf_prepare_sample(struct perf_event_header *header, } } -void perf_event_output(struct perf_event *event, - struct perf_sample_data *data, - struct pt_regs *regs) +static void __always_inline +__perf_event_output(struct perf_event *event, + struct perf_sample_data *data, + struct pt_regs *regs, + int (*output_begin)(struct perf_output_handle *, + struct perf_event *, + unsigned int)) { struct perf_output_handle handle; struct perf_event_header header; @@ -5650,7 +5781,7 @@ void perf_event_output(struct perf_event *event, perf_prepare_sample(&header, data, event, regs); - if (perf_output_begin(&handle, event, header.size)) + if (output_begin(&handle, event, header.size)) goto exit; perf_output_sample(&handle, &header, data, event); @@ -5661,6 +5792,30 @@ exit: rcu_read_unlock(); } +void +perf_event_output_forward(struct perf_event *event, + struct perf_sample_data *data, + struct pt_regs *regs) +{ + __perf_event_output(event, data, regs, perf_output_begin_forward); +} + +void +perf_event_output_backward(struct perf_event *event, + struct perf_sample_data *data, + struct pt_regs *regs) +{ + __perf_event_output(event, data, regs, perf_output_begin_backward); +} + +void +perf_event_output(struct perf_event *event, + struct perf_sample_data *data, + struct pt_regs *regs) +{ + __perf_event_output(event, data, regs, perf_output_begin); +} + /* * read event_id */ @@ -5706,15 +5861,18 @@ typedef void (perf_event_aux_output_cb)(struct perf_event *event, void *data); static void perf_event_aux_ctx(struct perf_event_context *ctx, perf_event_aux_output_cb output, - void *data) + void *data, bool all) { struct perf_event *event; list_for_each_entry_rcu(event, &ctx->event_list, event_entry) { - if (event->state < PERF_EVENT_STATE_INACTIVE) - continue; - if (!event_filter_match(event)) - continue; + if (!all) { + if (event->state < PERF_EVENT_STATE_INACTIVE) + continue; + if (!event_filter_match(event)) + continue; + } + output(event, data); } } @@ -5725,7 +5883,7 @@ perf_event_aux_task_ctx(perf_event_aux_output_cb output, void *data, { rcu_read_lock(); preempt_disable(); - perf_event_aux_ctx(task_ctx, output, data); + perf_event_aux_ctx(task_ctx, output, data, false); preempt_enable(); rcu_read_unlock(); } @@ -5755,13 +5913,13 @@ perf_event_aux(perf_event_aux_output_cb output, void *data, cpuctx = get_cpu_ptr(pmu->pmu_cpu_context); if (cpuctx->unique_pmu != pmu) goto next; - perf_event_aux_ctx(&cpuctx->ctx, output, data); + perf_event_aux_ctx(&cpuctx->ctx, output, data, false); ctxn = pmu->task_ctx_nr; if (ctxn < 0) goto next; ctx = rcu_dereference(current->perf_event_ctxp[ctxn]); if (ctx) - perf_event_aux_ctx(ctx, output, data); + perf_event_aux_ctx(ctx, output, data, false); next: put_cpu_ptr(pmu->pmu_cpu_context); } @@ -5769,6 +5927,134 @@ next: } /* + * Clear all file-based filters at exec, they'll have to be + * re-instated when/if these objects are mmapped again. + */ +static void perf_event_addr_filters_exec(struct perf_event *event, void *data) +{ + struct perf_addr_filters_head *ifh = perf_event_addr_filters(event); + struct perf_addr_filter *filter; + unsigned int restart = 0, count = 0; + unsigned long flags; + + if (!has_addr_filter(event)) + return; + + raw_spin_lock_irqsave(&ifh->lock, flags); + list_for_each_entry(filter, &ifh->list, entry) { + if (filter->inode) { + event->addr_filters_offs[count] = 0; + restart++; + } + + count++; + } + + if (restart) + event->addr_filters_gen++; + raw_spin_unlock_irqrestore(&ifh->lock, flags); + + if (restart) + perf_event_restart(event); +} + +void perf_event_exec(void) +{ + struct perf_event_context *ctx; + int ctxn; + + rcu_read_lock(); + for_each_task_context_nr(ctxn) { + ctx = current->perf_event_ctxp[ctxn]; + if (!ctx) + continue; + + perf_event_enable_on_exec(ctxn); + + perf_event_aux_ctx(ctx, perf_event_addr_filters_exec, NULL, + true); + } + rcu_read_unlock(); +} + +struct remote_output { + struct ring_buffer *rb; + int err; +}; + +static void __perf_event_output_stop(struct perf_event *event, void *data) +{ + struct perf_event *parent = event->parent; + struct remote_output *ro = data; + struct ring_buffer *rb = ro->rb; + struct stop_event_data sd = { + .event = event, + }; + + if (!has_aux(event)) + return; + + if (!parent) + parent = event; + + /* + * In case of inheritance, it will be the parent that links to the + * ring-buffer, but it will be the child that's actually using it: + */ + if (rcu_dereference(parent->rb) == rb) + ro->err = __perf_event_stop(&sd); +} + +static int __perf_pmu_output_stop(void *info) +{ + struct perf_event *event = info; + struct pmu *pmu = event->pmu; + struct perf_cpu_context *cpuctx = get_cpu_ptr(pmu->pmu_cpu_context); + struct remote_output ro = { + .rb = event->rb, + }; + + rcu_read_lock(); + perf_event_aux_ctx(&cpuctx->ctx, __perf_event_output_stop, &ro, false); + if (cpuctx->task_ctx) + perf_event_aux_ctx(cpuctx->task_ctx, __perf_event_output_stop, + &ro, false); + rcu_read_unlock(); + + return ro.err; +} + +static void perf_pmu_output_stop(struct perf_event *event) +{ + struct perf_event *iter; + int err, cpu; + +restart: + rcu_read_lock(); + list_for_each_entry_rcu(iter, &event->rb->event_list, rb_entry) { + /* + * For per-CPU events, we need to make sure that neither they + * nor their children are running; for cpu==-1 events it's + * sufficient to stop the event itself if it's active, since + * it can't have children. + */ + cpu = iter->cpu; + if (cpu == -1) + cpu = READ_ONCE(iter->oncpu); + + if (cpu == -1) + continue; + + err = cpu_function_call(cpu, __perf_pmu_output_stop, event); + if (err == -EAGAIN) { + rcu_read_unlock(); + goto restart; + } + } + rcu_read_unlock(); +} + +/* * task tracking -- fork/exit * * enabled by: attr.comm | attr.mmap | attr.mmap2 | attr.mmap_data | attr.task @@ -6177,6 +6463,87 @@ got_name: kfree(buf); } +/* + * Whether this @filter depends on a dynamic object which is not loaded + * yet or its load addresses are not known. + */ +static bool perf_addr_filter_needs_mmap(struct perf_addr_filter *filter) +{ + return filter->filter && filter->inode; +} + +/* + * Check whether inode and address range match filter criteria. + */ +static bool perf_addr_filter_match(struct perf_addr_filter *filter, + struct file *file, unsigned long offset, + unsigned long size) +{ + if (filter->inode != file->f_inode) + return false; + + if (filter->offset > offset + size) + return false; + + if (filter->offset + filter->size < offset) + return false; + + return true; +} + +static void __perf_addr_filters_adjust(struct perf_event *event, void *data) +{ + struct perf_addr_filters_head *ifh = perf_event_addr_filters(event); + struct vm_area_struct *vma = data; + unsigned long off = vma->vm_pgoff << PAGE_SHIFT, flags; + struct file *file = vma->vm_file; + struct perf_addr_filter *filter; + unsigned int restart = 0, count = 0; + + if (!has_addr_filter(event)) + return; + + if (!file) + return; + + raw_spin_lock_irqsave(&ifh->lock, flags); + list_for_each_entry(filter, &ifh->list, entry) { + if (perf_addr_filter_match(filter, file, off, + vma->vm_end - vma->vm_start)) { + event->addr_filters_offs[count] = vma->vm_start; + restart++; + } + + count++; + } + + if (restart) + event->addr_filters_gen++; + raw_spin_unlock_irqrestore(&ifh->lock, flags); + + if (restart) + perf_event_restart(event); +} + +/* + * Adjust all task's events' filters to the new vma + */ +static void perf_addr_filters_adjust(struct vm_area_struct *vma) +{ + struct perf_event_context *ctx; + int ctxn; + + rcu_read_lock(); + for_each_task_context_nr(ctxn) { + ctx = rcu_dereference(current->perf_event_ctxp[ctxn]); + if (!ctx) + continue; + + perf_event_aux_ctx(ctx, __perf_addr_filters_adjust, vma, true); + } + rcu_read_unlock(); +} + void perf_event_mmap(struct vm_area_struct *vma) { struct perf_mmap_event mmap_event; @@ -6208,6 +6575,7 @@ void perf_event_mmap(struct vm_area_struct *vma) /* .flags (attr_mmap2 only) */ }; + perf_addr_filters_adjust(vma); perf_event_mmap_event(&mmap_event); } @@ -6499,10 +6867,7 @@ static int __perf_event_overflow(struct perf_event *event, irq_work_queue(&event->pending); } - if (event->overflow_handler) - event->overflow_handler(event, data, regs); - else - perf_event_output(event, data, regs); + event->overflow_handler(event, data, regs); if (*perf_event_fasync(event) && event->pending_kill) { event->pending_wakeup = 1; @@ -6735,7 +7100,7 @@ int perf_swevent_get_recursion_context(void) } EXPORT_SYMBOL_GPL(perf_swevent_get_recursion_context); -inline void perf_swevent_put_recursion_context(int rctx) +void perf_swevent_put_recursion_context(int rctx) { struct swevent_htable *swhash = this_cpu_ptr(&swevent_htable); @@ -6997,7 +7362,26 @@ static int perf_tp_event_match(struct perf_event *event, return 1; } -void perf_tp_event(u64 addr, u64 count, void *record, int entry_size, +void perf_trace_run_bpf_submit(void *raw_data, int size, int rctx, + struct trace_event_call *call, u64 count, + struct pt_regs *regs, struct hlist_head *head, + struct task_struct *task) +{ + struct bpf_prog *prog = call->prog; + + if (prog) { + *(struct pt_regs **)raw_data = regs; + if (!trace_call_bpf(prog, raw_data) || hlist_empty(head)) { + perf_swevent_put_recursion_context(rctx); + return; + } + } + perf_tp_event(call->event.type, count, raw_data, size, regs, head, + rctx, task); +} +EXPORT_SYMBOL_GPL(perf_trace_run_bpf_submit); + +void perf_tp_event(u16 event_type, u64 count, void *record, int entry_size, struct pt_regs *regs, struct hlist_head *head, int rctx, struct task_struct *task) { @@ -7009,9 +7393,11 @@ void perf_tp_event(u64 addr, u64 count, void *record, int entry_size, .data = record, }; - perf_sample_data_init(&data, addr, 0); + perf_sample_data_init(&data, 0, 0); data.raw = &raw; + perf_trace_buf_update(record, event_type); + hlist_for_each_entry_rcu(event, head, hlist_entry) { if (perf_tp_event_match(event, &data, regs)) perf_swevent_event(event, count, &data, regs); @@ -7089,24 +7475,6 @@ static inline void perf_tp_register(void) perf_pmu_register(&perf_tracepoint, "tracepoint", PERF_TYPE_TRACEPOINT); } -static int perf_event_set_filter(struct perf_event *event, void __user *arg) -{ - char *filter_str; - int ret; - - if (event->attr.type != PERF_TYPE_TRACEPOINT) - return -EINVAL; - - filter_str = strndup_user(arg, PAGE_SIZE); - if (IS_ERR(filter_str)) - return PTR_ERR(filter_str); - - ret = ftrace_profile_set_filter(event, event->attr.config, filter_str); - - kfree(filter_str); - return ret; -} - static void perf_event_free_filter(struct perf_event *event) { ftrace_profile_free_filter(event); @@ -7114,6 +7482,7 @@ static void perf_event_free_filter(struct perf_event *event) static int perf_event_set_bpf_prog(struct perf_event *event, u32 prog_fd) { + bool is_kprobe, is_tracepoint; struct bpf_prog *prog; if (event->attr.type != PERF_TYPE_TRACEPOINT) @@ -7122,20 +7491,31 @@ static int perf_event_set_bpf_prog(struct perf_event *event, u32 prog_fd) if (event->tp_event->prog) return -EEXIST; - if (!(event->tp_event->flags & TRACE_EVENT_FL_UKPROBE)) - /* bpf programs can only be attached to u/kprobes */ + is_kprobe = event->tp_event->flags & TRACE_EVENT_FL_UKPROBE; + is_tracepoint = event->tp_event->flags & TRACE_EVENT_FL_TRACEPOINT; + if (!is_kprobe && !is_tracepoint) + /* bpf programs can only be attached to u/kprobe or tracepoint */ return -EINVAL; prog = bpf_prog_get(prog_fd); if (IS_ERR(prog)) return PTR_ERR(prog); - if (prog->type != BPF_PROG_TYPE_KPROBE) { + if ((is_kprobe && prog->type != BPF_PROG_TYPE_KPROBE) || + (is_tracepoint && prog->type != BPF_PROG_TYPE_TRACEPOINT)) { /* valid fd, but invalid bpf program type */ bpf_prog_put(prog); return -EINVAL; } + if (is_tracepoint) { + int off = trace_event_get_offsets(event->tp_event); + + if (prog->aux->max_ctx_offset > off) { + bpf_prog_put(prog); + return -EACCES; + } + } event->tp_event->prog = prog; return 0; @@ -7161,11 +7541,6 @@ static inline void perf_tp_register(void) { } -static int perf_event_set_filter(struct perf_event *event, void __user *arg) -{ - return -ENOENT; -} - static void perf_event_free_filter(struct perf_event *event) { } @@ -7194,6 +7569,387 @@ void perf_bp_event(struct perf_event *bp, void *data) #endif /* + * Allocate a new address filter + */ +static struct perf_addr_filter * +perf_addr_filter_new(struct perf_event *event, struct list_head *filters) +{ + int node = cpu_to_node(event->cpu == -1 ? 0 : event->cpu); + struct perf_addr_filter *filter; + + filter = kzalloc_node(sizeof(*filter), GFP_KERNEL, node); + if (!filter) + return NULL; + + INIT_LIST_HEAD(&filter->entry); + list_add_tail(&filter->entry, filters); + + return filter; +} + +static void free_filters_list(struct list_head *filters) +{ + struct perf_addr_filter *filter, *iter; + + list_for_each_entry_safe(filter, iter, filters, entry) { + if (filter->inode) + iput(filter->inode); + list_del(&filter->entry); + kfree(filter); + } +} + +/* + * Free existing address filters and optionally install new ones + */ +static void perf_addr_filters_splice(struct perf_event *event, + struct list_head *head) +{ + unsigned long flags; + LIST_HEAD(list); + + if (!has_addr_filter(event)) + return; + + /* don't bother with children, they don't have their own filters */ + if (event->parent) + return; + + raw_spin_lock_irqsave(&event->addr_filters.lock, flags); + + list_splice_init(&event->addr_filters.list, &list); + if (head) + list_splice(head, &event->addr_filters.list); + + raw_spin_unlock_irqrestore(&event->addr_filters.lock, flags); + + free_filters_list(&list); +} + +/* + * Scan through mm's vmas and see if one of them matches the + * @filter; if so, adjust filter's address range. + * Called with mm::mmap_sem down for reading. + */ +static unsigned long perf_addr_filter_apply(struct perf_addr_filter *filter, + struct mm_struct *mm) +{ + struct vm_area_struct *vma; + + for (vma = mm->mmap; vma; vma = vma->vm_next) { + struct file *file = vma->vm_file; + unsigned long off = vma->vm_pgoff << PAGE_SHIFT; + unsigned long vma_size = vma->vm_end - vma->vm_start; + + if (!file) + continue; + + if (!perf_addr_filter_match(filter, file, off, vma_size)) + continue; + + return vma->vm_start; + } + + return 0; +} + +/* + * Update event's address range filters based on the + * task's existing mappings, if any. + */ +static void perf_event_addr_filters_apply(struct perf_event *event) +{ + struct perf_addr_filters_head *ifh = perf_event_addr_filters(event); + struct task_struct *task = READ_ONCE(event->ctx->task); + struct perf_addr_filter *filter; + struct mm_struct *mm = NULL; + unsigned int count = 0; + unsigned long flags; + + /* + * We may observe TASK_TOMBSTONE, which means that the event tear-down + * will stop on the parent's child_mutex that our caller is also holding + */ + if (task == TASK_TOMBSTONE) + return; + + mm = get_task_mm(event->ctx->task); + if (!mm) + goto restart; + + down_read(&mm->mmap_sem); + + raw_spin_lock_irqsave(&ifh->lock, flags); + list_for_each_entry(filter, &ifh->list, entry) { + event->addr_filters_offs[count] = 0; + + if (perf_addr_filter_needs_mmap(filter)) + event->addr_filters_offs[count] = + perf_addr_filter_apply(filter, mm); + + count++; + } + + event->addr_filters_gen++; + raw_spin_unlock_irqrestore(&ifh->lock, flags); + + up_read(&mm->mmap_sem); + + mmput(mm); + +restart: + perf_event_restart(event); +} + +/* + * Address range filtering: limiting the data to certain + * instruction address ranges. Filters are ioctl()ed to us from + * userspace as ascii strings. + * + * Filter string format: + * + * ACTION RANGE_SPEC + * where ACTION is one of the + * * "filter": limit the trace to this region + * * "start": start tracing from this address + * * "stop": stop tracing at this address/region; + * RANGE_SPEC is + * * for kernel addresses: <start address>[/<size>] + * * for object files: <start address>[/<size>]@</path/to/object/file> + * + * if <size> is not specified, the range is treated as a single address. + */ +enum { + IF_ACT_FILTER, + IF_ACT_START, + IF_ACT_STOP, + IF_SRC_FILE, + IF_SRC_KERNEL, + IF_SRC_FILEADDR, + IF_SRC_KERNELADDR, +}; + +enum { + IF_STATE_ACTION = 0, + IF_STATE_SOURCE, + IF_STATE_END, +}; + +static const match_table_t if_tokens = { + { IF_ACT_FILTER, "filter" }, + { IF_ACT_START, "start" }, + { IF_ACT_STOP, "stop" }, + { IF_SRC_FILE, "%u/%u@%s" }, + { IF_SRC_KERNEL, "%u/%u" }, + { IF_SRC_FILEADDR, "%u@%s" }, + { IF_SRC_KERNELADDR, "%u" }, +}; + +/* + * Address filter string parser + */ +static int +perf_event_parse_addr_filter(struct perf_event *event, char *fstr, + struct list_head *filters) +{ + struct perf_addr_filter *filter = NULL; + char *start, *orig, *filename = NULL; + struct path path; + substring_t args[MAX_OPT_ARGS]; + int state = IF_STATE_ACTION, token; + unsigned int kernel = 0; + int ret = -EINVAL; + + orig = fstr = kstrdup(fstr, GFP_KERNEL); + if (!fstr) + return -ENOMEM; + + while ((start = strsep(&fstr, " ,\n")) != NULL) { + ret = -EINVAL; + + if (!*start) + continue; + + /* filter definition begins */ + if (state == IF_STATE_ACTION) { + filter = perf_addr_filter_new(event, filters); + if (!filter) + goto fail; + } + + token = match_token(start, if_tokens, args); + switch (token) { + case IF_ACT_FILTER: + case IF_ACT_START: + filter->filter = 1; + + case IF_ACT_STOP: + if (state != IF_STATE_ACTION) + goto fail; + + state = IF_STATE_SOURCE; + break; + + case IF_SRC_KERNELADDR: + case IF_SRC_KERNEL: + kernel = 1; + + case IF_SRC_FILEADDR: + case IF_SRC_FILE: + if (state != IF_STATE_SOURCE) + goto fail; + + if (token == IF_SRC_FILE || token == IF_SRC_KERNEL) + filter->range = 1; + + *args[0].to = 0; + ret = kstrtoul(args[0].from, 0, &filter->offset); + if (ret) + goto fail; + + if (filter->range) { + *args[1].to = 0; + ret = kstrtoul(args[1].from, 0, &filter->size); + if (ret) + goto fail; + } + + if (token == IF_SRC_FILE) { + filename = match_strdup(&args[2]); + if (!filename) { + ret = -ENOMEM; + goto fail; + } + } + + state = IF_STATE_END; + break; + + default: + goto fail; + } + + /* + * Filter definition is fully parsed, validate and install it. + * Make sure that it doesn't contradict itself or the event's + * attribute. + */ + if (state == IF_STATE_END) { + if (kernel && event->attr.exclude_kernel) + goto fail; + + if (!kernel) { + if (!filename) + goto fail; + + /* look up the path and grab its inode */ + ret = kern_path(filename, LOOKUP_FOLLOW, &path); + if (ret) + goto fail_free_name; + + filter->inode = igrab(d_inode(path.dentry)); + path_put(&path); + kfree(filename); + filename = NULL; + + ret = -EINVAL; + if (!filter->inode || + !S_ISREG(filter->inode->i_mode)) + /* free_filters_list() will iput() */ + goto fail; + } + + /* ready to consume more filters */ + state = IF_STATE_ACTION; + filter = NULL; + } + } + + if (state != IF_STATE_ACTION) + goto fail; + + kfree(orig); + + return 0; + +fail_free_name: + kfree(filename); +fail: + free_filters_list(filters); + kfree(orig); + + return ret; +} + +static int +perf_event_set_addr_filter(struct perf_event *event, char *filter_str) +{ + LIST_HEAD(filters); + int ret; + + /* + * Since this is called in perf_ioctl() path, we're already holding + * ctx::mutex. + */ + lockdep_assert_held(&event->ctx->mutex); + + if (WARN_ON_ONCE(event->parent)) + return -EINVAL; + + /* + * For now, we only support filtering in per-task events; doing so + * for CPU-wide events requires additional context switching trickery, + * since same object code will be mapped at different virtual + * addresses in different processes. + */ + if (!event->ctx->task) + return -EOPNOTSUPP; + + ret = perf_event_parse_addr_filter(event, filter_str, &filters); + if (ret) + return ret; + + ret = event->pmu->addr_filters_validate(&filters); + if (ret) { + free_filters_list(&filters); + return ret; + } + + /* remove existing filters, if any */ + perf_addr_filters_splice(event, &filters); + + /* install new filters */ + perf_event_for_each_child(event, perf_event_addr_filters_apply); + + return ret; +} + +static int perf_event_set_filter(struct perf_event *event, void __user *arg) +{ + char *filter_str; + int ret = -EINVAL; + + if ((event->attr.type != PERF_TYPE_TRACEPOINT || + !IS_ENABLED(CONFIG_EVENT_TRACING)) && + !has_addr_filter(event)) + return -EINVAL; + + filter_str = strndup_user(arg, PAGE_SIZE); + if (IS_ERR(filter_str)) + return PTR_ERR(filter_str); + + if (IS_ENABLED(CONFIG_EVENT_TRACING) && + event->attr.type == PERF_TYPE_TRACEPOINT) + ret = ftrace_profile_set_filter(event, event->attr.config, + filter_str); + else if (has_addr_filter(event)) + ret = perf_event_set_addr_filter(event, filter_str); + + kfree(filter_str); + return ret; +} + +/* * hrtimer based swevent callback */ @@ -7550,6 +8306,20 @@ static void free_pmu_context(struct pmu *pmu) out: mutex_unlock(&pmus_lock); } + +/* + * Let userspace know that this PMU supports address range filtering: + */ +static ssize_t nr_addr_filters_show(struct device *dev, + struct device_attribute *attr, + char *page) +{ + struct pmu *pmu = dev_get_drvdata(dev); + + return snprintf(page, PAGE_SIZE - 1, "%d\n", pmu->nr_addr_filters); +} +DEVICE_ATTR_RO(nr_addr_filters); + static struct idr pmu_idr; static ssize_t @@ -7651,9 +8421,19 @@ static int pmu_dev_alloc(struct pmu *pmu) if (ret) goto free_dev; + /* For PMUs with address filters, throw in an extra attribute: */ + if (pmu->nr_addr_filters) + ret = device_create_file(pmu->dev, &dev_attr_nr_addr_filters); + + if (ret) + goto del_dev; + out: return ret; +del_dev: + device_del(pmu->dev); + free_dev: put_device(pmu->dev); goto out; @@ -7693,6 +8473,21 @@ int perf_pmu_register(struct pmu *pmu, const char *name, int type) } skip_type: + if (pmu->task_ctx_nr == perf_hw_context) { + static int hw_context_taken = 0; + + /* + * Other than systems with heterogeneous CPUs, it never makes + * sense for two PMUs to share perf_hw_context. PMUs which are + * uncore must use perf_invalid_context. + */ + if (WARN_ON_ONCE(hw_context_taken && + !(pmu->capabilities & PERF_PMU_CAP_HETEROGENEOUS_CPUS))) + pmu->task_ctx_nr = perf_invalid_context; + + hw_context_taken = 1; + } + pmu->pmu_cpu_context = find_pmu_context(pmu->task_ctx_nr); if (pmu->pmu_cpu_context) goto got_cpu_context; @@ -7780,6 +8575,8 @@ void perf_pmu_unregister(struct pmu *pmu) free_percpu(pmu->pmu_disable_count); if (pmu->type >= PERF_TYPE_MAX) idr_remove(&pmu_idr, pmu->type); + if (pmu->nr_addr_filters) + device_remove_file(pmu->dev, &dev_attr_nr_addr_filters); device_del(pmu->dev); put_device(pmu->dev); free_pmu_context(pmu); @@ -7973,6 +8770,7 @@ perf_event_alloc(struct perf_event_attr *attr, int cpu, INIT_LIST_HEAD(&event->sibling_list); INIT_LIST_HEAD(&event->rb_entry); INIT_LIST_HEAD(&event->active_entry); + INIT_LIST_HEAD(&event->addr_filters.list); INIT_HLIST_NODE(&event->hlist_entry); @@ -7980,6 +8778,7 @@ perf_event_alloc(struct perf_event_attr *attr, int cpu, init_irq_work(&event->pending, perf_pending_event); mutex_init(&event->mmap_mutex); + raw_spin_lock_init(&event->addr_filters.lock); atomic_long_set(&event->refcount, 1); event->cpu = cpu; @@ -8014,8 +8813,16 @@ perf_event_alloc(struct perf_event_attr *attr, int cpu, context = parent_event->overflow_handler_context; } - event->overflow_handler = overflow_handler; - event->overflow_handler_context = context; + if (overflow_handler) { + event->overflow_handler = overflow_handler; + event->overflow_handler_context = context; + } else if (is_write_backward(event)){ + event->overflow_handler = perf_event_output_backward; + event->overflow_handler_context = NULL; + } else { + event->overflow_handler = perf_event_output_forward; + event->overflow_handler_context = NULL; + } perf_event__state_init(event); @@ -8056,11 +8863,22 @@ perf_event_alloc(struct perf_event_attr *attr, int cpu, if (err) goto err_pmu; + if (has_addr_filter(event)) { + event->addr_filters_offs = kcalloc(pmu->nr_addr_filters, + sizeof(unsigned long), + GFP_KERNEL); + if (!event->addr_filters_offs) + goto err_per_task; + + /* force hw sync on the address filters */ + event->addr_filters_gen = 1; + } + if (!event->parent) { if (event->attr.sample_type & PERF_SAMPLE_CALLCHAIN) { err = get_callchain_buffers(); if (err) - goto err_per_task; + goto err_addr_filters; } } @@ -8069,6 +8887,9 @@ perf_event_alloc(struct perf_event_attr *attr, int cpu, return event; +err_addr_filters: + kfree(event->addr_filters_offs); + err_per_task: exclusive_event_destroy(event); @@ -8248,6 +9069,13 @@ perf_event_set_output(struct perf_event *event, struct perf_event *output_event) goto out; /* + * Either writing ring buffer from beginning or from end. + * Mixing is not allowed. + */ + if (is_write_backward(output_event) != is_write_backward(event)) + goto out; + + /* * If both events generate aux data, they must be on the same PMU */ if (has_aux(event) && has_aux(output_event) && @@ -8413,6 +9241,24 @@ SYSCALL_DEFINE5(perf_event_open, get_online_cpus(); + if (task) { + err = mutex_lock_interruptible(&task->signal->cred_guard_mutex); + if (err) + goto err_cpus; + + /* + * Reuse ptrace permission checks for now. + * + * We must hold cred_guard_mutex across this and any potential + * perf_install_in_context() call for this new event to + * serialize against exec() altering our credentials (and the + * perf_event_exit_task() that could imply). + */ + err = -EACCES; + if (!ptrace_may_access(task, PTRACE_MODE_READ_REALCREDS)) + goto err_cred; + } + if (flags & PERF_FLAG_PID_CGROUP) cgroup_fd = pid; @@ -8420,7 +9266,7 @@ SYSCALL_DEFINE5(perf_event_open, NULL, NULL, cgroup_fd); if (IS_ERR(event)) { err = PTR_ERR(event); - goto err_cpus; + goto err_cred; } if (is_sampling_event(event)) { @@ -8479,11 +9325,6 @@ SYSCALL_DEFINE5(perf_event_open, goto err_context; } - if (task) { - put_task_struct(task); - task = NULL; - } - /* * Look up the group leader (we will attach this event to it): */ @@ -8581,6 +9422,11 @@ SYSCALL_DEFINE5(perf_event_open, WARN_ON_ONCE(ctx->parent_ctx); + /* + * This is the point on no return; we cannot fail hereafter. This is + * where we start modifying current state. + */ + if (move_group) { /* * See perf_event_ctx_lock() for comments on the details @@ -8652,6 +9498,11 @@ SYSCALL_DEFINE5(perf_event_open, mutex_unlock(&gctx->mutex); mutex_unlock(&ctx->mutex); + if (task) { + mutex_unlock(&task->signal->cred_guard_mutex); + put_task_struct(task); + } + put_online_cpus(); mutex_lock(¤t->perf_event_mutex); @@ -8684,6 +9535,9 @@ err_alloc: */ if (!event_file) free_event(event); +err_cred: + if (task) + mutex_unlock(&task->signal->cred_guard_mutex); err_cpus: put_online_cpus(); err_task: @@ -8968,6 +9822,9 @@ static void perf_event_exit_task_context(struct task_struct *child, int ctxn) /* * When a child task exits, feed back event values to parent events. + * + * Can be called with cred_guard_mutex held when called from + * install_exec_creds(). */ void perf_event_exit_task(struct task_struct *child) { diff --git a/kernel/events/internal.h b/kernel/events/internal.h index 4199b6d193f5..05f9f6d626df 100644 --- a/kernel/events/internal.h +++ b/kernel/events/internal.h @@ -11,13 +11,13 @@ struct ring_buffer { atomic_t refcount; struct rcu_head rcu_head; - struct irq_work irq_work; #ifdef CONFIG_PERF_USE_VMALLOC struct work_struct work; int page_order; /* allocation order */ #endif int nr_pages; /* nr of data pages */ int overwrite; /* can overwrite itself */ + int paused; /* can write into ring buffer */ atomic_t poll; /* POLL_ for wakeups */ @@ -65,6 +65,14 @@ static inline void rb_free_rcu(struct rcu_head *rcu_head) rb_free(rb); } +static inline void rb_toggle_paused(struct ring_buffer *rb, bool pause) +{ + if (!pause && rb->nr_pages) + rb->paused = 0; + else + rb->paused = 1; +} + extern struct ring_buffer * rb_alloc(int nr_pages, long watermark, int cpu, int flags); extern void perf_event_wakeup(struct perf_event *event); diff --git a/kernel/events/ring_buffer.c b/kernel/events/ring_buffer.c index c61f0cbd308b..ae9b90dc9a5a 100644 --- a/kernel/events/ring_buffer.c +++ b/kernel/events/ring_buffer.c @@ -102,8 +102,21 @@ out: preempt_enable(); } -int perf_output_begin(struct perf_output_handle *handle, - struct perf_event *event, unsigned int size) +static bool __always_inline +ring_buffer_has_space(unsigned long head, unsigned long tail, + unsigned long data_size, unsigned int size, + bool backward) +{ + if (!backward) + return CIRC_SPACE(head, tail, data_size) >= size; + else + return CIRC_SPACE(tail, head, data_size) >= size; +} + +static int __always_inline +__perf_output_begin(struct perf_output_handle *handle, + struct perf_event *event, unsigned int size, + bool backward) { struct ring_buffer *rb; unsigned long tail, offset, head; @@ -125,8 +138,11 @@ int perf_output_begin(struct perf_output_handle *handle, if (unlikely(!rb)) goto out; - if (unlikely(!rb->nr_pages)) + if (unlikely(rb->paused)) { + if (rb->nr_pages) + local_inc(&rb->lost); goto out; + } handle->rb = rb; handle->event = event; @@ -143,9 +159,12 @@ int perf_output_begin(struct perf_output_handle *handle, do { tail = READ_ONCE(rb->user_page->data_tail); offset = head = local_read(&rb->head); - if (!rb->overwrite && - unlikely(CIRC_SPACE(head, tail, perf_data_size(rb)) < size)) - goto fail; + if (!rb->overwrite) { + if (unlikely(!ring_buffer_has_space(head, tail, + perf_data_size(rb), + size, backward))) + goto fail; + } /* * The above forms a control dependency barrier separating the @@ -159,9 +178,17 @@ int perf_output_begin(struct perf_output_handle *handle, * See perf_output_put_handle(). */ - head += size; + if (!backward) + head += size; + else + head -= size; } while (local_cmpxchg(&rb->head, offset, head) != offset); + if (backward) { + offset = head; + head = (u64)(-head); + } + /* * We rely on the implied barrier() by local_cmpxchg() to ensure * none of the data stores below can be lifted up by the compiler. @@ -203,6 +230,26 @@ out: return -ENOSPC; } +int perf_output_begin_forward(struct perf_output_handle *handle, + struct perf_event *event, unsigned int size) +{ + return __perf_output_begin(handle, event, size, false); +} + +int perf_output_begin_backward(struct perf_output_handle *handle, + struct perf_event *event, unsigned int size) +{ + return __perf_output_begin(handle, event, size, true); +} + +int perf_output_begin(struct perf_output_handle *handle, + struct perf_event *event, unsigned int size) +{ + + return __perf_output_begin(handle, event, size, + unlikely(is_write_backward(event))); +} + unsigned int perf_output_copy(struct perf_output_handle *handle, const void *buf, unsigned int len) { @@ -221,8 +268,6 @@ void perf_output_end(struct perf_output_handle *handle) rcu_read_unlock(); } -static void rb_irq_work(struct irq_work *work); - static void ring_buffer_init(struct ring_buffer *rb, long watermark, int flags) { @@ -243,16 +288,13 @@ ring_buffer_init(struct ring_buffer *rb, long watermark, int flags) INIT_LIST_HEAD(&rb->event_list); spin_lock_init(&rb->event_lock); - init_irq_work(&rb->irq_work, rb_irq_work); -} -static void ring_buffer_put_async(struct ring_buffer *rb) -{ - if (!atomic_dec_and_test(&rb->refcount)) - return; - - rb->rcu_head.next = (void *)rb; - irq_work_queue(&rb->irq_work); + /* + * perf_output_begin() only checks rb->paused, therefore + * rb->paused must be true if we have no pages for output. + */ + if (!rb->nr_pages) + rb->paused = 1; } /* @@ -264,6 +306,10 @@ static void ring_buffer_put_async(struct ring_buffer *rb) * The ordering is similar to that of perf_output_{begin,end}, with * the exception of (B), which should be taken care of by the pmu * driver, since ordering rules will differ depending on hardware. + * + * Call this from pmu::start(); see the comment in perf_aux_output_end() + * about its use in pmu callbacks. Both can also be called from the PMI + * handler if needed. */ void *perf_aux_output_begin(struct perf_output_handle *handle, struct perf_event *event) @@ -288,6 +334,13 @@ void *perf_aux_output_begin(struct perf_output_handle *handle, goto err; /* + * If rb::aux_mmap_count is zero (and rb_has_aux() above went through), + * the aux buffer is in perf_mmap_close(), about to get freed. + */ + if (!atomic_read(&rb->aux_mmap_count)) + goto err_put; + + /* * Nesting is not supported for AUX area, make sure nested * writers are caught early */ @@ -328,10 +381,11 @@ void *perf_aux_output_begin(struct perf_output_handle *handle, return handle->rb->aux_priv; err_put: + /* can't be last */ rb_free_aux(rb); err: - ring_buffer_put_async(rb); + ring_buffer_put(rb); handle->event = NULL; return NULL; @@ -342,11 +396,16 @@ err: * aux_head and posting a PERF_RECORD_AUX into the perf buffer. It is the * pmu driver's responsibility to observe ordering rules of the hardware, * so that all the data is externally visible before this is called. + * + * Note: this has to be called from pmu::stop() callback, as the assumption + * of the AUX buffer management code is that after pmu::stop(), the AUX + * transaction must be stopped and therefore drop the AUX reference count. */ void perf_aux_output_end(struct perf_output_handle *handle, unsigned long size, bool truncated) { struct ring_buffer *rb = handle->rb; + bool wakeup = truncated; unsigned long aux_head; u64 flags = 0; @@ -375,14 +434,22 @@ void perf_aux_output_end(struct perf_output_handle *handle, unsigned long size, aux_head = rb->user_page->aux_head = local_read(&rb->aux_head); if (aux_head - local_read(&rb->aux_wakeup) >= rb->aux_watermark) { - perf_output_wakeup(handle); + wakeup = true; local_add(rb->aux_watermark, &rb->aux_wakeup); } + + if (wakeup) { + if (truncated) + handle->event->pending_disable = 1; + perf_output_wakeup(handle); + } + handle->event = NULL; local_set(&rb->aux_nest, 0); + /* can't be last */ rb_free_aux(rb); - ring_buffer_put_async(rb); + ring_buffer_put(rb); } /* @@ -463,6 +530,14 @@ static void __rb_free_aux(struct ring_buffer *rb) { int pg; + /* + * Should never happen, the last reference should be dropped from + * perf_mmap_close() path, which first stops aux transactions (which + * in turn are the atomic holders of aux_refcount) and then does the + * last rb_free_aux(). + */ + WARN_ON_ONCE(in_atomic()); + if (rb->aux_priv) { rb->free_aux(rb->aux_priv); rb->free_aux = NULL; @@ -574,18 +649,7 @@ out: void rb_free_aux(struct ring_buffer *rb) { if (atomic_dec_and_test(&rb->aux_refcount)) - irq_work_queue(&rb->irq_work); -} - -static void rb_irq_work(struct irq_work *work) -{ - struct ring_buffer *rb = container_of(work, struct ring_buffer, irq_work); - - if (!atomic_read(&rb->aux_refcount)) __rb_free_aux(rb); - - if (rb->rcu_head.next == (void *)rb) - call_rcu(&rb->rcu_head, rb_free_rcu); } #ifndef CONFIG_PERF_USE_VMALLOC diff --git a/kernel/events/uprobes.c b/kernel/events/uprobes.c index 220fc17b9718..7edc95edfaee 100644 --- a/kernel/events/uprobes.c +++ b/kernel/events/uprobes.c @@ -321,7 +321,7 @@ retry: copy_to_page(new_page, vaddr, &opcode, UPROBE_SWBP_INSN_SIZE); ret = __replace_page(vma, vaddr, old_page, new_page); - page_cache_release(new_page); + put_page(new_page); put_old: put_page(old_page); @@ -539,14 +539,14 @@ static int __copy_insn(struct address_space *mapping, struct file *filp, * see uprobe_register(). */ if (mapping->a_ops->readpage) - page = read_mapping_page(mapping, offset >> PAGE_CACHE_SHIFT, filp); + page = read_mapping_page(mapping, offset >> PAGE_SHIFT, filp); else - page = shmem_read_mapping_page(mapping, offset >> PAGE_CACHE_SHIFT); + page = shmem_read_mapping_page(mapping, offset >> PAGE_SHIFT); if (IS_ERR(page)) return PTR_ERR(page); copy_from_page(page, offset, insn, nbytes); - page_cache_release(page); + put_page(page); return 0; } diff --git a/kernel/fork.c b/kernel/fork.c index d277e83ed3e0..3e8451527cbe 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -1494,7 +1494,7 @@ static struct task_struct *copy_process(unsigned long clone_flags, * sigaltstack should be cleared when sharing the same VM */ if ((clone_flags & (CLONE_VM|CLONE_VFORK)) == CLONE_VM) - p->sas_ss_sp = p->sas_ss_size = 0; + sas_ss_reset(p); /* * Syscall tracing and stepping should be turned off in the diff --git a/kernel/futex.c b/kernel/futex.c index a5d2e74c89e0..c20f06f38ef3 100644 --- a/kernel/futex.c +++ b/kernel/futex.c @@ -1295,10 +1295,20 @@ static int wake_futex_pi(u32 __user *uaddr, u32 uval, struct futex_q *this, if (unlikely(should_fail_futex(true))) ret = -EFAULT; - if (cmpxchg_futex_value_locked(&curval, uaddr, uval, newval)) + if (cmpxchg_futex_value_locked(&curval, uaddr, uval, newval)) { ret = -EFAULT; - else if (curval != uval) - ret = -EINVAL; + } else if (curval != uval) { + /* + * If a unconditional UNLOCK_PI operation (user space did not + * try the TID->0 transition) raced with a waiter setting the + * FUTEX_WAITERS flag between get_user() and locking the hash + * bucket lock, retry the operation. + */ + if ((FUTEX_TID_MASK & curval) == uval) + ret = -EAGAIN; + else + ret = -EINVAL; + } if (ret) { raw_spin_unlock_irq(&pi_state->pi_mutex.wait_lock); return ret; @@ -1525,8 +1535,8 @@ void requeue_futex(struct futex_q *q, struct futex_hash_bucket *hb1, if (likely(&hb1->chain != &hb2->chain)) { plist_del(&q->list, &hb1->chain); hb_waiters_dec(hb1); - plist_add(&q->list, &hb2->chain); hb_waiters_inc(hb2); + plist_add(&q->list, &hb2->chain); q->lock_ptr = &hb2->lock; } get_futex_key_refs(key2); @@ -2623,6 +2633,15 @@ retry: if (ret == -EFAULT) goto pi_faulted; /* + * A unconditional UNLOCK_PI op raced against a waiter + * setting the FUTEX_WAITERS bit. Try again. + */ + if (ret == -EAGAIN) { + spin_unlock(&hb->lock); + put_futex_key(&key); + goto retry; + } + /* * wake_futex_pi has detected invalid state. Tell user * space. */ diff --git a/kernel/irq/ipi.c b/kernel/irq/ipi.c index c37f34b00a11..c42742208e5e 100644 --- a/kernel/irq/ipi.c +++ b/kernel/irq/ipi.c @@ -19,9 +19,9 @@ * * Allocate a virq that can be used to send IPI to any CPU in dest mask. * - * On success it'll return linux irq number and 0 on failure + * On success it'll return linux irq number and error code on failure */ -unsigned int irq_reserve_ipi(struct irq_domain *domain, +int irq_reserve_ipi(struct irq_domain *domain, const struct cpumask *dest) { unsigned int nr_irqs, offset; @@ -30,18 +30,18 @@ unsigned int irq_reserve_ipi(struct irq_domain *domain, if (!domain ||!irq_domain_is_ipi(domain)) { pr_warn("Reservation on a non IPI domain\n"); - return 0; + return -EINVAL; } if (!cpumask_subset(dest, cpu_possible_mask)) { pr_warn("Reservation is not in possible_cpu_mask\n"); - return 0; + return -EINVAL; } nr_irqs = cpumask_weight(dest); if (!nr_irqs) { pr_warn("Reservation for empty destination mask\n"); - return 0; + return -EINVAL; } if (irq_domain_is_ipi_single(domain)) { @@ -72,14 +72,14 @@ unsigned int irq_reserve_ipi(struct irq_domain *domain, next = cpumask_next(next, dest); if (next < nr_cpu_ids) { pr_warn("Destination mask has holes\n"); - return 0; + return -EINVAL; } } virq = irq_domain_alloc_descs(-1, nr_irqs, 0, NUMA_NO_NODE); if (virq <= 0) { pr_warn("Can't reserve IPI, failed to alloc descs\n"); - return 0; + return -ENOMEM; } virq = __irq_domain_alloc_irqs(domain, virq, nr_irqs, NUMA_NO_NODE, @@ -94,22 +94,26 @@ unsigned int irq_reserve_ipi(struct irq_domain *domain, data = irq_get_irq_data(virq + i); cpumask_copy(data->common->affinity, dest); data->common->ipi_offset = offset; + irq_set_status_flags(virq + i, IRQ_NO_BALANCING); } return virq; free_descs: irq_free_descs(virq, nr_irqs); - return 0; + return -EBUSY; } /** * irq_destroy_ipi() - unreserve an IPI that was previously allocated * @irq: linux irq number to be destroyed + * @dest: cpumask of cpus which should have the IPI removed * - * Return the IPIs allocated with irq_reserve_ipi() to the system destroying - * all virqs associated with them. + * The IPIs allocated with irq_reserve_ipi() are retuerned to the system + * destroying all virqs associated with them. + * + * Return 0 on success or error code on failure. */ -void irq_destroy_ipi(unsigned int irq) +int irq_destroy_ipi(unsigned int irq, const struct cpumask *dest) { struct irq_data *data = irq_get_irq_data(irq); struct cpumask *ipimask = data ? irq_data_get_affinity_mask(data) : NULL; @@ -117,7 +121,7 @@ void irq_destroy_ipi(unsigned int irq) unsigned int nr_irqs; if (!irq || !data || !ipimask) - return; + return -EINVAL; domain = data->domain; if (WARN_ON(domain == NULL)) @@ -125,15 +129,25 @@ void irq_destroy_ipi(unsigned int irq) if (!irq_domain_is_ipi(domain)) { pr_warn("Trying to destroy a non IPI domain!\n"); - return; + return -EINVAL; } - if (irq_domain_is_ipi_per_cpu(domain)) - nr_irqs = cpumask_weight(ipimask); - else + if (WARN_ON(!cpumask_subset(dest, ipimask))) + /* + * Must be destroying a subset of CPUs to which this IPI + * was set up to target + */ + return -EINVAL; + + if (irq_domain_is_ipi_per_cpu(domain)) { + irq = irq + cpumask_first(dest) - data->common->ipi_offset; + nr_irqs = cpumask_weight(dest); + } else { nr_irqs = 1; + } irq_domain_free_irqs(irq, nr_irqs); + return 0; } /** diff --git a/kernel/irq/irqdesc.c b/kernel/irq/irqdesc.c index 0ccd028817d7..8731e1c5d1e7 100644 --- a/kernel/irq/irqdesc.c +++ b/kernel/irq/irqdesc.c @@ -595,7 +595,8 @@ void __irq_put_desc_unlock(struct irq_desc *desc, unsigned long flags, bool bus) chip_bus_sync_unlock(desc); } -int irq_set_percpu_devid(unsigned int irq) +int irq_set_percpu_devid_partition(unsigned int irq, + const struct cpumask *affinity) { struct irq_desc *desc = irq_to_desc(irq); @@ -610,10 +611,33 @@ int irq_set_percpu_devid(unsigned int irq) if (!desc->percpu_enabled) return -ENOMEM; + if (affinity) + desc->percpu_affinity = affinity; + else + desc->percpu_affinity = cpu_possible_mask; + irq_set_percpu_devid_flags(irq); return 0; } +int irq_set_percpu_devid(unsigned int irq) +{ + return irq_set_percpu_devid_partition(irq, NULL); +} + +int irq_get_percpu_devid_partition(unsigned int irq, struct cpumask *affinity) +{ + struct irq_desc *desc = irq_to_desc(irq); + + if (!desc || !desc->percpu_enabled) + return -EINVAL; + + if (affinity) + cpumask_copy(affinity, desc->percpu_affinity); + + return 0; +} + void kstat_incr_irq_this_cpu(unsigned int irq) { kstat_incr_irqs_this_cpu(irq_to_desc(irq)); diff --git a/kernel/irq/irqdomain.c b/kernel/irq/irqdomain.c index 3a519a01118b..d65f6f31a5b3 100644 --- a/kernel/irq/irqdomain.c +++ b/kernel/irq/irqdomain.c @@ -243,14 +243,15 @@ struct irq_domain *irq_domain_add_legacy(struct device_node *of_node, EXPORT_SYMBOL_GPL(irq_domain_add_legacy); /** - * irq_find_matching_fwnode() - Locates a domain for a given fwnode - * @fwnode: FW descriptor of the interrupt controller + * irq_find_matching_fwspec() - Locates a domain for a given fwspec + * @fwspec: FW specifier for an interrupt * @bus_token: domain-specific data */ -struct irq_domain *irq_find_matching_fwnode(struct fwnode_handle *fwnode, +struct irq_domain *irq_find_matching_fwspec(struct irq_fwspec *fwspec, enum irq_domain_bus_token bus_token) { struct irq_domain *h, *found = NULL; + struct fwnode_handle *fwnode = fwspec->fwnode; int rc; /* We might want to match the legacy controller last since @@ -264,7 +265,9 @@ struct irq_domain *irq_find_matching_fwnode(struct fwnode_handle *fwnode, */ mutex_lock(&irq_domain_mutex); list_for_each_entry(h, &irq_domain_list, link) { - if (h->ops->match) + if (h->ops->select && fwspec->param_count) + rc = h->ops->select(h, fwspec, bus_token); + else if (h->ops->match) rc = h->ops->match(h, to_of_node(fwnode), bus_token); else rc = ((fwnode != NULL) && (h->fwnode == fwnode) && @@ -279,7 +282,7 @@ struct irq_domain *irq_find_matching_fwnode(struct fwnode_handle *fwnode, mutex_unlock(&irq_domain_mutex); return found; } -EXPORT_SYMBOL_GPL(irq_find_matching_fwnode); +EXPORT_SYMBOL_GPL(irq_find_matching_fwspec); /** * irq_set_default_host() - Set a "default" irq domain @@ -574,11 +577,9 @@ unsigned int irq_create_fwspec_mapping(struct irq_fwspec *fwspec) int virq; if (fwspec->fwnode) { - domain = irq_find_matching_fwnode(fwspec->fwnode, - DOMAIN_BUS_WIRED); + domain = irq_find_matching_fwspec(fwspec, DOMAIN_BUS_WIRED); if (!domain) - domain = irq_find_matching_fwnode(fwspec->fwnode, - DOMAIN_BUS_ANY); + domain = irq_find_matching_fwspec(fwspec, DOMAIN_BUS_ANY); } else { domain = irq_default_domain; } @@ -1099,6 +1100,7 @@ void irq_domain_free_irqs_common(struct irq_domain *domain, unsigned int virq, } irq_domain_free_irqs_parent(domain, virq, nr_irqs); } +EXPORT_SYMBOL_GPL(irq_domain_free_irqs_common); /** * irq_domain_free_irqs_top - Clear handler and handler data, clear irqdata and free parent diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c index cc1cc641d653..ef0bc02c3a70 100644 --- a/kernel/irq/manage.c +++ b/kernel/irq/manage.c @@ -1407,7 +1407,7 @@ int setup_irq(unsigned int irq, struct irqaction *act) int retval; struct irq_desc *desc = irq_to_desc(irq); - if (WARN_ON(irq_settings_is_per_cpu_devid(desc))) + if (!desc || WARN_ON(irq_settings_is_per_cpu_devid(desc))) return -EINVAL; chip_bus_lock(desc); retval = __setup_irq(irq, desc, act); diff --git a/kernel/kcov.c b/kernel/kcov.c index 3efbee0834a8..a02f2dddd1d7 100644 --- a/kernel/kcov.c +++ b/kernel/kcov.c @@ -1,5 +1,6 @@ #define pr_fmt(fmt) "kcov: " fmt +#define DISABLE_BRANCH_PROFILING #include <linux/compiler.h> #include <linux/types.h> #include <linux/file.h> @@ -43,7 +44,7 @@ struct kcov { * Entry point from instrumented code. * This is called once per basic-block/edge. */ -void __sanitizer_cov_trace_pc(void) +void notrace __sanitizer_cov_trace_pc(void) { struct task_struct *t; enum kcov_mode mode; diff --git a/kernel/kexec_core.c b/kernel/kexec_core.c index 8d34308ea449..1391d3ee3b86 100644 --- a/kernel/kexec_core.c +++ b/kernel/kexec_core.c @@ -1415,6 +1415,9 @@ static int __init crash_save_vmcoreinfo_init(void) VMCOREINFO_OFFSET(page, lru); VMCOREINFO_OFFSET(page, _mapcount); VMCOREINFO_OFFSET(page, private); + VMCOREINFO_OFFSET(page, compound_dtor); + VMCOREINFO_OFFSET(page, compound_order); + VMCOREINFO_OFFSET(page, compound_head); VMCOREINFO_OFFSET(pglist_data, node_zones); VMCOREINFO_OFFSET(pglist_data, nr_zones); #ifdef CONFIG_FLAT_NODE_MEM_MAP @@ -1447,8 +1450,8 @@ static int __init crash_save_vmcoreinfo_init(void) #ifdef CONFIG_X86 VMCOREINFO_NUMBER(KERNEL_IMAGE_SIZE); #endif -#ifdef CONFIG_HUGETLBFS - VMCOREINFO_SYMBOL(free_huge_page); +#ifdef CONFIG_HUGETLB_PAGE + VMCOREINFO_NUMBER(HUGETLB_PAGE_DTOR); #endif arch_crash_save_vmcoreinfo(); diff --git a/kernel/livepatch/core.c b/kernel/livepatch/core.c index d68fbf63b083..5c2bc1052691 100644 --- a/kernel/livepatch/core.c +++ b/kernel/livepatch/core.c @@ -28,6 +28,8 @@ #include <linux/list.h> #include <linux/kallsyms.h> #include <linux/livepatch.h> +#include <linux/elf.h> +#include <linux/moduleloader.h> #include <asm/cacheflush.h> /** @@ -204,75 +206,109 @@ static int klp_find_object_symbol(const char *objname, const char *name, return -EINVAL; } -/* - * external symbols are located outside the parent object (where the parent - * object is either vmlinux or the kmod being patched). - */ -static int klp_find_external_symbol(struct module *pmod, const char *name, - unsigned long *addr) +static int klp_resolve_symbols(Elf_Shdr *relasec, struct module *pmod) { - const struct kernel_symbol *sym; - - /* first, check if it's an exported symbol */ - preempt_disable(); - sym = find_symbol(name, NULL, NULL, true, true); - if (sym) { - *addr = sym->value; - preempt_enable(); - return 0; - } - preempt_enable(); + int i, cnt, vmlinux, ret; + char objname[MODULE_NAME_LEN]; + char symname[KSYM_NAME_LEN]; + char *strtab = pmod->core_kallsyms.strtab; + Elf_Rela *relas; + Elf_Sym *sym; + unsigned long sympos, addr; /* - * Check if it's in another .o within the patch module. This also - * checks that the external symbol is unique. + * Since the field widths for objname and symname in the sscanf() + * call are hard-coded and correspond to MODULE_NAME_LEN and + * KSYM_NAME_LEN respectively, we must make sure that MODULE_NAME_LEN + * and KSYM_NAME_LEN have the values we expect them to have. + * + * Because the value of MODULE_NAME_LEN can differ among architectures, + * we use the smallest/strictest upper bound possible (56, based on + * the current definition of MODULE_NAME_LEN) to prevent overflows. */ - return klp_find_object_symbol(pmod->name, name, 0, addr); + BUILD_BUG_ON(MODULE_NAME_LEN < 56 || KSYM_NAME_LEN != 128); + + relas = (Elf_Rela *) relasec->sh_addr; + /* For each rela in this klp relocation section */ + for (i = 0; i < relasec->sh_size / sizeof(Elf_Rela); i++) { + sym = pmod->core_kallsyms.symtab + ELF_R_SYM(relas[i].r_info); + if (sym->st_shndx != SHN_LIVEPATCH) { + pr_err("symbol %s is not marked as a livepatch symbol", + strtab + sym->st_name); + return -EINVAL; + } + + /* Format: .klp.sym.objname.symname,sympos */ + cnt = sscanf(strtab + sym->st_name, + ".klp.sym.%55[^.].%127[^,],%lu", + objname, symname, &sympos); + if (cnt != 3) { + pr_err("symbol %s has an incorrectly formatted name", + strtab + sym->st_name); + return -EINVAL; + } + + /* klp_find_object_symbol() treats a NULL objname as vmlinux */ + vmlinux = !strcmp(objname, "vmlinux"); + ret = klp_find_object_symbol(vmlinux ? NULL : objname, + symname, sympos, &addr); + if (ret) + return ret; + + sym->st_value = addr; + } + + return 0; } static int klp_write_object_relocations(struct module *pmod, struct klp_object *obj) { - int ret = 0; - unsigned long val; - struct klp_reloc *reloc; + int i, cnt, ret = 0; + const char *objname, *secname; + char sec_objname[MODULE_NAME_LEN]; + Elf_Shdr *sec; if (WARN_ON(!klp_is_object_loaded(obj))) return -EINVAL; - if (WARN_ON(!obj->relocs)) - return -EINVAL; + objname = klp_is_module(obj) ? obj->name : "vmlinux"; module_disable_ro(pmod); + /* For each klp relocation section */ + for (i = 1; i < pmod->klp_info->hdr.e_shnum; i++) { + sec = pmod->klp_info->sechdrs + i; + secname = pmod->klp_info->secstrings + sec->sh_name; + if (!(sec->sh_flags & SHF_RELA_LIVEPATCH)) + continue; - for (reloc = obj->relocs; reloc->name; reloc++) { - /* discover the address of the referenced symbol */ - if (reloc->external) { - if (reloc->sympos > 0) { - pr_err("non-zero sympos for external reloc symbol '%s' is not supported\n", - reloc->name); - ret = -EINVAL; - goto out; - } - ret = klp_find_external_symbol(pmod, reloc->name, &val); - } else - ret = klp_find_object_symbol(obj->name, - reloc->name, - reloc->sympos, - &val); + /* + * Format: .klp.rela.sec_objname.section_name + * See comment in klp_resolve_symbols() for an explanation + * of the selected field width value. + */ + cnt = sscanf(secname, ".klp.rela.%55[^.]", sec_objname); + if (cnt != 1) { + pr_err("section %s has an incorrectly formatted name", + secname); + ret = -EINVAL; + break; + } + + if (strcmp(objname, sec_objname)) + continue; + + ret = klp_resolve_symbols(sec, pmod); if (ret) - goto out; + break; - ret = klp_write_module_reloc(pmod, reloc->type, reloc->loc, - val + reloc->addend); - if (ret) { - pr_err("relocation failed for symbol '%s' at 0x%016lx (%d)\n", - reloc->name, val, ret); - goto out; - } + ret = apply_relocate_add(pmod->klp_info->sechdrs, + pmod->core_kallsyms.strtab, + pmod->klp_info->symndx, i, pmod); + if (ret) + break; } -out: module_enable_ro(pmod); return ret; } @@ -298,6 +334,19 @@ unlock: rcu_read_unlock(); } +/* + * Convert a function address into the appropriate ftrace location. + * + * Usually this is just the address of the function, but on some architectures + * it's more complicated so allow them to provide a custom behaviour. + */ +#ifndef klp_get_ftrace_location +static unsigned long klp_get_ftrace_location(unsigned long faddr) +{ + return faddr; +} +#endif + static void klp_disable_func(struct klp_func *func) { struct klp_ops *ops; @@ -312,8 +361,14 @@ static void klp_disable_func(struct klp_func *func) return; if (list_is_singular(&ops->func_stack)) { + unsigned long ftrace_loc; + + ftrace_loc = klp_get_ftrace_location(func->old_addr); + if (WARN_ON(!ftrace_loc)) + return; + WARN_ON(unregister_ftrace_function(&ops->fops)); - WARN_ON(ftrace_set_filter_ip(&ops->fops, func->old_addr, 1, 0)); + WARN_ON(ftrace_set_filter_ip(&ops->fops, ftrace_loc, 1, 0)); list_del_rcu(&func->stack_node); list_del(&ops->node); @@ -338,6 +393,15 @@ static int klp_enable_func(struct klp_func *func) ops = klp_find_ops(func->old_addr); if (!ops) { + unsigned long ftrace_loc; + + ftrace_loc = klp_get_ftrace_location(func->old_addr); + if (!ftrace_loc) { + pr_err("failed to find location for function '%s'\n", + func->old_name); + return -EINVAL; + } + ops = kzalloc(sizeof(*ops), GFP_KERNEL); if (!ops) return -ENOMEM; @@ -352,7 +416,7 @@ static int klp_enable_func(struct klp_func *func) INIT_LIST_HEAD(&ops->func_stack); list_add_rcu(&func->stack_node, &ops->func_stack); - ret = ftrace_set_filter_ip(&ops->fops, func->old_addr, 0, 0); + ret = ftrace_set_filter_ip(&ops->fops, ftrace_loc, 0, 0); if (ret) { pr_err("failed to set ftrace filter for function '%s' (%d)\n", func->old_name, ret); @@ -363,7 +427,7 @@ static int klp_enable_func(struct klp_func *func) if (ret) { pr_err("failed to register ftrace handler for function '%s' (%d)\n", func->old_name, ret); - ftrace_set_filter_ip(&ops->fops, func->old_addr, 1, 0); + ftrace_set_filter_ip(&ops->fops, ftrace_loc, 1, 0); goto err; } @@ -683,6 +747,9 @@ static void klp_free_patch(struct klp_patch *patch) static int klp_init_func(struct klp_object *obj, struct klp_func *func) { + if (!func->old_name || !func->new_func) + return -EINVAL; + INIT_LIST_HEAD(&func->stack_node); func->state = KLP_DISABLED; @@ -703,11 +770,9 @@ static int klp_init_object_loaded(struct klp_patch *patch, struct klp_func *func; int ret; - if (obj->relocs) { - ret = klp_write_object_relocations(patch->mod, obj); - if (ret) - return ret; - } + ret = klp_write_object_relocations(patch->mod, obj); + if (ret) + return ret; klp_for_each_func(obj, func) { ret = klp_find_object_symbol(obj->name, func->old_name, @@ -842,12 +907,18 @@ int klp_register_patch(struct klp_patch *patch) { int ret; - if (!klp_initialized()) - return -ENODEV; - if (!patch || !patch->mod) return -EINVAL; + if (!is_livepatch_module(patch->mod)) { + pr_err("module %s is not marked as a livepatch module", + patch->mod->name); + return -EINVAL; + } + + if (!klp_initialized()) + return -ENODEV; + /* * A reference is taken on the patch module to prevent it from being * unloaded. Right now, we don't allow patch modules to unload since diff --git a/kernel/locking/lockdep.c b/kernel/locking/lockdep.c index 2324ba5310db..81f1a7107c0e 100644 --- a/kernel/locking/lockdep.c +++ b/kernel/locking/lockdep.c @@ -45,6 +45,7 @@ #include <linux/bitops.h> #include <linux/gfp.h> #include <linux/kmemcheck.h> +#include <linux/random.h> #include <asm/sections.h> @@ -708,7 +709,7 @@ look_up_lock_class(struct lockdep_map *lock, unsigned int subclass) * yet. Otherwise we look it up. We cache the result in the lock object * itself, so actual lookup of the hash should be once per lock object. */ -static inline struct lock_class * +static struct lock_class * register_lock_class(struct lockdep_map *lock, unsigned int subclass, int force) { struct lockdep_subclass_key *key; @@ -1999,6 +2000,7 @@ static inline int get_first_held_lock(struct task_struct *curr, return ++i; } +#ifdef CONFIG_DEBUG_LOCKDEP /* * Returns the next chain_key iteration */ @@ -2069,6 +2071,7 @@ static void print_collision(struct task_struct *curr, printk("\nstack backtrace:\n"); dump_stack(); } +#endif /* * Checks whether the chain and the current held locks are consistent @@ -2174,15 +2177,37 @@ cache_hit: chain->irq_context = hlock->irq_context; i = get_first_held_lock(curr, hlock); chain->depth = curr->lockdep_depth + 1 - i; + + BUILD_BUG_ON((1UL << 24) <= ARRAY_SIZE(chain_hlocks)); + BUILD_BUG_ON((1UL << 6) <= ARRAY_SIZE(curr->held_locks)); + BUILD_BUG_ON((1UL << 8*sizeof(chain_hlocks[0])) <= ARRAY_SIZE(lock_classes)); + if (likely(nr_chain_hlocks + chain->depth <= MAX_LOCKDEP_CHAIN_HLOCKS)) { chain->base = nr_chain_hlocks; - nr_chain_hlocks += chain->depth; for (j = 0; j < chain->depth - 1; j++, i++) { int lock_id = curr->held_locks[i].class_idx - 1; chain_hlocks[chain->base + j] = lock_id; } chain_hlocks[chain->base + j] = class - lock_classes; } + + if (nr_chain_hlocks < MAX_LOCKDEP_CHAIN_HLOCKS) + nr_chain_hlocks += chain->depth; + +#ifdef CONFIG_DEBUG_LOCKDEP + /* + * Important for check_no_collision(). + */ + if (unlikely(nr_chain_hlocks > MAX_LOCKDEP_CHAIN_HLOCKS)) { + if (debug_locks_off_graph_unlock()) + return 0; + + print_lockdep_off("BUG: MAX_LOCKDEP_CHAIN_HLOCKS too low!"); + dump_stack(); + return 0; + } +#endif + hlist_add_head_rcu(&chain->entry, hash_head); debug_atomic_inc(chain_lookup_misses); inc_chains(); @@ -2930,6 +2955,11 @@ static int mark_irqflags(struct task_struct *curr, struct held_lock *hlock) return 1; } +static inline unsigned int task_irq_context(struct task_struct *task) +{ + return 2 * !!task->hardirq_context + !!task->softirq_context; +} + static int separate_irq_context(struct task_struct *curr, struct held_lock *hlock) { @@ -2938,8 +2968,6 @@ static int separate_irq_context(struct task_struct *curr, /* * Keep track of points where we cross into an interrupt context: */ - hlock->irq_context = 2*(curr->hardirq_context ? 1 : 0) + - curr->softirq_context; if (depth) { struct held_lock *prev_hlock; @@ -2971,6 +2999,11 @@ static inline int mark_irqflags(struct task_struct *curr, return 1; } +static inline unsigned int task_irq_context(struct task_struct *task) +{ + return 0; +} + static inline int separate_irq_context(struct task_struct *curr, struct held_lock *hlock) { @@ -3239,6 +3272,7 @@ static int __lock_acquire(struct lockdep_map *lock, unsigned int subclass, hlock->acquire_ip = ip; hlock->instance = lock; hlock->nest_lock = nest_lock; + hlock->irq_context = task_irq_context(curr); hlock->trylock = trylock; hlock->read = read; hlock->check = check; @@ -3552,7 +3586,35 @@ static int __lock_is_held(struct lockdep_map *lock) return 0; } -static void __lock_pin_lock(struct lockdep_map *lock) +static struct pin_cookie __lock_pin_lock(struct lockdep_map *lock) +{ + struct pin_cookie cookie = NIL_COOKIE; + struct task_struct *curr = current; + int i; + + if (unlikely(!debug_locks)) + return cookie; + + for (i = 0; i < curr->lockdep_depth; i++) { + struct held_lock *hlock = curr->held_locks + i; + + if (match_held_lock(hlock, lock)) { + /* + * Grab 16bits of randomness; this is sufficient to not + * be guessable and still allows some pin nesting in + * our u32 pin_count. + */ + cookie.val = 1 + (prandom_u32() >> 16); + hlock->pin_count += cookie.val; + return cookie; + } + } + + WARN(1, "pinning an unheld lock\n"); + return cookie; +} + +static void __lock_repin_lock(struct lockdep_map *lock, struct pin_cookie cookie) { struct task_struct *curr = current; int i; @@ -3564,7 +3626,7 @@ static void __lock_pin_lock(struct lockdep_map *lock) struct held_lock *hlock = curr->held_locks + i; if (match_held_lock(hlock, lock)) { - hlock->pin_count++; + hlock->pin_count += cookie.val; return; } } @@ -3572,7 +3634,7 @@ static void __lock_pin_lock(struct lockdep_map *lock) WARN(1, "pinning an unheld lock\n"); } -static void __lock_unpin_lock(struct lockdep_map *lock) +static void __lock_unpin_lock(struct lockdep_map *lock, struct pin_cookie cookie) { struct task_struct *curr = current; int i; @@ -3587,7 +3649,11 @@ static void __lock_unpin_lock(struct lockdep_map *lock) if (WARN(!hlock->pin_count, "unpinning an unpinned lock\n")) return; - hlock->pin_count--; + hlock->pin_count -= cookie.val; + + if (WARN((int)hlock->pin_count < 0, "pin count corrupted\n")) + hlock->pin_count = 0; + return; } } @@ -3718,24 +3784,44 @@ int lock_is_held(struct lockdep_map *lock) } EXPORT_SYMBOL_GPL(lock_is_held); -void lock_pin_lock(struct lockdep_map *lock) +struct pin_cookie lock_pin_lock(struct lockdep_map *lock) { + struct pin_cookie cookie = NIL_COOKIE; unsigned long flags; if (unlikely(current->lockdep_recursion)) - return; + return cookie; raw_local_irq_save(flags); check_flags(flags); current->lockdep_recursion = 1; - __lock_pin_lock(lock); + cookie = __lock_pin_lock(lock); current->lockdep_recursion = 0; raw_local_irq_restore(flags); + + return cookie; } EXPORT_SYMBOL_GPL(lock_pin_lock); -void lock_unpin_lock(struct lockdep_map *lock) +void lock_repin_lock(struct lockdep_map *lock, struct pin_cookie cookie) +{ + unsigned long flags; + + if (unlikely(current->lockdep_recursion)) + return; + + raw_local_irq_save(flags); + check_flags(flags); + + current->lockdep_recursion = 1; + __lock_repin_lock(lock, cookie); + current->lockdep_recursion = 0; + raw_local_irq_restore(flags); +} +EXPORT_SYMBOL_GPL(lock_repin_lock); + +void lock_unpin_lock(struct lockdep_map *lock, struct pin_cookie cookie) { unsigned long flags; @@ -3746,7 +3832,7 @@ void lock_unpin_lock(struct lockdep_map *lock) check_flags(flags); current->lockdep_recursion = 1; - __lock_unpin_lock(lock); + __lock_unpin_lock(lock, cookie); current->lockdep_recursion = 0; raw_local_irq_restore(flags); } diff --git a/kernel/locking/lockdep_proc.c b/kernel/locking/lockdep_proc.c index dbb61a302548..a0f61effad25 100644 --- a/kernel/locking/lockdep_proc.c +++ b/kernel/locking/lockdep_proc.c @@ -141,6 +141,8 @@ static int lc_show(struct seq_file *m, void *v) int i; if (v == SEQ_START_TOKEN) { + if (nr_chain_hlocks > MAX_LOCKDEP_CHAIN_HLOCKS) + seq_printf(m, "(buggered) "); seq_printf(m, "all lock chains:\n"); return 0; } diff --git a/kernel/locking/locktorture.c b/kernel/locking/locktorture.c index 8ef1919d63b2..f8c5af52a131 100644 --- a/kernel/locking/locktorture.c +++ b/kernel/locking/locktorture.c @@ -75,12 +75,7 @@ struct lock_stress_stats { long n_lock_acquired; }; -#if defined(MODULE) -#define LOCKTORTURE_RUNNABLE_INIT 1 -#else -#define LOCKTORTURE_RUNNABLE_INIT 0 -#endif -int torture_runnable = LOCKTORTURE_RUNNABLE_INIT; +int torture_runnable = IS_ENABLED(MODULE); module_param(torture_runnable, int, 0444); MODULE_PARM_DESC(torture_runnable, "Start locktorture at module init"); @@ -394,12 +389,12 @@ static void torture_rtmutex_boost(struct torture_random_state *trsp) if (!rt_task(current)) { /* - * (1) Boost priority once every ~50k operations. When the + * Boost priority once every ~50k operations. When the * task tries to take the lock, the rtmutex it will account * for the new priority, and do any corresponding pi-dance. */ - if (!(torture_random(trsp) % - (cxt.nrealwriters_stress * factor))) { + if (trsp && !(torture_random(trsp) % + (cxt.nrealwriters_stress * factor))) { policy = SCHED_FIFO; param.sched_priority = MAX_RT_PRIO - 1; } else /* common case, do nothing */ @@ -748,6 +743,15 @@ static void lock_torture_cleanup(void) if (torture_cleanup_begin()) return; + /* + * Indicates early cleanup, meaning that the test has not run, + * such as when passing bogus args when loading the module. As + * such, only perform the underlying torture-specific cleanups, + * and avoid anything related to locktorture. + */ + if (!cxt.lwsa) + goto end; + if (writer_tasks) { for (i = 0; i < cxt.nrealwriters_stress; i++) torture_stop_kthread(lock_torture_writer, @@ -776,6 +780,7 @@ static void lock_torture_cleanup(void) else lock_torture_print_module_parms(cxt.cur_ops, "End of test: SUCCESS"); +end: torture_cleanup_end(); } @@ -870,6 +875,7 @@ static int __init lock_torture_init(void) VERBOSE_TOROUT_STRING("cxt.lrsa: Out of memory"); firsterr = -ENOMEM; kfree(cxt.lwsa); + cxt.lwsa = NULL; goto unwind; } @@ -878,6 +884,7 @@ static int __init lock_torture_init(void) cxt.lrsa[i].n_lock_acquired = 0; } } + lock_torture_print_module_parms(cxt.cur_ops, "Start of test"); /* Prepare torture context. */ diff --git a/kernel/locking/qspinlock_stat.h b/kernel/locking/qspinlock_stat.h index eb2a2c9bc3fc..22e025309845 100644 --- a/kernel/locking/qspinlock_stat.h +++ b/kernel/locking/qspinlock_stat.h @@ -136,10 +136,12 @@ static ssize_t qstat_read(struct file *file, char __user *user_buf, } if (counter == qstat_pv_hash_hops) { - u64 frac; + u64 frac = 0; - frac = 100ULL * do_div(stat, kicks); - frac = DIV_ROUND_CLOSEST_ULL(frac, kicks); + if (kicks) { + frac = 100ULL * do_div(stat, kicks); + frac = DIV_ROUND_CLOSEST_ULL(frac, kicks); + } /* * Return a X.XX decimal number @@ -189,8 +191,6 @@ static ssize_t qstat_write(struct file *file, const char __user *user_buf, for (i = 0 ; i < qstat_num; i++) WRITE_ONCE(ptr[i], 0); - for (i = 0 ; i < qstat_num; i++) - WRITE_ONCE(ptr[i], 0); } return count; } @@ -212,10 +212,8 @@ static int __init init_qspinlock_stat(void) struct dentry *d_qstat = debugfs_create_dir("qlockstat", NULL); int i; - if (!d_qstat) { - pr_warn("Could not create 'qlockstat' debugfs directory\n"); - return 0; - } + if (!d_qstat) + goto out; /* * Create the debugfs files @@ -225,12 +223,20 @@ static int __init init_qspinlock_stat(void) * performance. */ for (i = 0; i < qstat_num; i++) - debugfs_create_file(qstat_names[i], 0400, d_qstat, - (void *)(long)i, &fops_qstat); + if (!debugfs_create_file(qstat_names[i], 0400, d_qstat, + (void *)(long)i, &fops_qstat)) + goto fail_undo; + + if (!debugfs_create_file(qstat_names[qstat_reset_cnts], 0200, d_qstat, + (void *)(long)qstat_reset_cnts, &fops_qstat)) + goto fail_undo; - debugfs_create_file(qstat_names[qstat_reset_cnts], 0200, d_qstat, - (void *)(long)qstat_reset_cnts, &fops_qstat); return 0; +fail_undo: + debugfs_remove_recursive(d_qstat); +out: + pr_warn("Could not create 'qlockstat' debugfs entries\n"); + return -ENOMEM; } fs_initcall(init_qspinlock_stat); diff --git a/kernel/locking/rwsem-spinlock.c b/kernel/locking/rwsem-spinlock.c index 3a5048572065..1591f6b3539f 100644 --- a/kernel/locking/rwsem-spinlock.c +++ b/kernel/locking/rwsem-spinlock.c @@ -191,11 +191,12 @@ int __down_read_trylock(struct rw_semaphore *sem) /* * get a write lock on the semaphore */ -void __sched __down_write_nested(struct rw_semaphore *sem, int subclass) +int __sched __down_write_common(struct rw_semaphore *sem, int state) { struct rwsem_waiter waiter; struct task_struct *tsk; unsigned long flags; + int ret = 0; raw_spin_lock_irqsave(&sem->wait_lock, flags); @@ -215,21 +216,33 @@ void __sched __down_write_nested(struct rw_semaphore *sem, int subclass) */ if (sem->count == 0) break; - set_task_state(tsk, TASK_UNINTERRUPTIBLE); + if (signal_pending_state(state, current)) { + ret = -EINTR; + goto out; + } + set_task_state(tsk, state); raw_spin_unlock_irqrestore(&sem->wait_lock, flags); schedule(); raw_spin_lock_irqsave(&sem->wait_lock, flags); } /* got the lock */ sem->count = -1; +out: list_del(&waiter.list); raw_spin_unlock_irqrestore(&sem->wait_lock, flags); + + return ret; } void __sched __down_write(struct rw_semaphore *sem) { - __down_write_nested(sem, 0); + __down_write_common(sem, TASK_UNINTERRUPTIBLE); +} + +int __sched __down_write_killable(struct rw_semaphore *sem) +{ + return __down_write_common(sem, TASK_KILLABLE); } /* diff --git a/kernel/locking/rwsem-xadd.c b/kernel/locking/rwsem-xadd.c index a4d4de05b2d1..09e30c6225e5 100644 --- a/kernel/locking/rwsem-xadd.c +++ b/kernel/locking/rwsem-xadd.c @@ -433,12 +433,13 @@ static inline bool rwsem_has_spinner(struct rw_semaphore *sem) /* * Wait until we successfully acquire the write lock */ -__visible -struct rw_semaphore __sched *rwsem_down_write_failed(struct rw_semaphore *sem) +static inline struct rw_semaphore * +__rwsem_down_write_failed_common(struct rw_semaphore *sem, int state) { long count; bool waiting = true; /* any queued threads before us */ struct rwsem_waiter waiter; + struct rw_semaphore *ret = sem; /* undo write bias from down_write operation, stop active locking */ count = rwsem_atomic_update(-RWSEM_ACTIVE_WRITE_BIAS, sem); @@ -478,7 +479,7 @@ struct rw_semaphore __sched *rwsem_down_write_failed(struct rw_semaphore *sem) count = rwsem_atomic_update(RWSEM_WAITING_BIAS, sem); /* wait until we successfully acquire the lock */ - set_current_state(TASK_UNINTERRUPTIBLE); + set_current_state(state); while (true) { if (rwsem_try_write_lock(count, sem)) break; @@ -486,21 +487,48 @@ struct rw_semaphore __sched *rwsem_down_write_failed(struct rw_semaphore *sem) /* Block until there are no active lockers. */ do { + if (signal_pending_state(state, current)) + goto out_nolock; + schedule(); - set_current_state(TASK_UNINTERRUPTIBLE); + set_current_state(state); } while ((count = sem->count) & RWSEM_ACTIVE_MASK); raw_spin_lock_irq(&sem->wait_lock); } __set_current_state(TASK_RUNNING); + list_del(&waiter.list); + raw_spin_unlock_irq(&sem->wait_lock); + return ret; + +out_nolock: + __set_current_state(TASK_RUNNING); + raw_spin_lock_irq(&sem->wait_lock); list_del(&waiter.list); + if (list_empty(&sem->wait_list)) + rwsem_atomic_update(-RWSEM_WAITING_BIAS, sem); + else + __rwsem_do_wake(sem, RWSEM_WAKE_ANY); raw_spin_unlock_irq(&sem->wait_lock); - return sem; + return ERR_PTR(-EINTR); +} + +__visible struct rw_semaphore * __sched +rwsem_down_write_failed(struct rw_semaphore *sem) +{ + return __rwsem_down_write_failed_common(sem, TASK_UNINTERRUPTIBLE); } EXPORT_SYMBOL(rwsem_down_write_failed); +__visible struct rw_semaphore * __sched +rwsem_down_write_failed_killable(struct rw_semaphore *sem) +{ + return __rwsem_down_write_failed_common(sem, TASK_KILLABLE); +} +EXPORT_SYMBOL(rwsem_down_write_failed_killable); + /* * handle waking up a waiter on the semaphore * - up_read/up_write has decremented the active part of count if we come here diff --git a/kernel/locking/rwsem.c b/kernel/locking/rwsem.c index 205be0ce34de..c817216c1615 100644 --- a/kernel/locking/rwsem.c +++ b/kernel/locking/rwsem.c @@ -55,6 +55,25 @@ void __sched down_write(struct rw_semaphore *sem) EXPORT_SYMBOL(down_write); /* + * lock for writing + */ +int __sched down_write_killable(struct rw_semaphore *sem) +{ + might_sleep(); + rwsem_acquire(&sem->dep_map, 0, 0, _RET_IP_); + + if (LOCK_CONTENDED_RETURN(sem, __down_write_trylock, __down_write_killable)) { + rwsem_release(&sem->dep_map, 1, _RET_IP_); + return -EINTR; + } + + rwsem_set_owner(sem); + return 0; +} + +EXPORT_SYMBOL(down_write_killable); + +/* * trylock for writing -- returns 1 if successful, 0 if contention */ int down_write_trylock(struct rw_semaphore *sem) diff --git a/kernel/module.c b/kernel/module.c index 041200ca4a2d..5f71aa63ed2a 100644 --- a/kernel/module.c +++ b/kernel/module.c @@ -1973,6 +1973,83 @@ static void module_enable_nx(const struct module *mod) { } static void module_disable_nx(const struct module *mod) { } #endif +#ifdef CONFIG_LIVEPATCH +/* + * Persist Elf information about a module. Copy the Elf header, + * section header table, section string table, and symtab section + * index from info to mod->klp_info. + */ +static int copy_module_elf(struct module *mod, struct load_info *info) +{ + unsigned int size, symndx; + int ret; + + size = sizeof(*mod->klp_info); + mod->klp_info = kmalloc(size, GFP_KERNEL); + if (mod->klp_info == NULL) + return -ENOMEM; + + /* Elf header */ + size = sizeof(mod->klp_info->hdr); + memcpy(&mod->klp_info->hdr, info->hdr, size); + + /* Elf section header table */ + size = sizeof(*info->sechdrs) * info->hdr->e_shnum; + mod->klp_info->sechdrs = kmalloc(size, GFP_KERNEL); + if (mod->klp_info->sechdrs == NULL) { + ret = -ENOMEM; + goto free_info; + } + memcpy(mod->klp_info->sechdrs, info->sechdrs, size); + + /* Elf section name string table */ + size = info->sechdrs[info->hdr->e_shstrndx].sh_size; + mod->klp_info->secstrings = kmalloc(size, GFP_KERNEL); + if (mod->klp_info->secstrings == NULL) { + ret = -ENOMEM; + goto free_sechdrs; + } + memcpy(mod->klp_info->secstrings, info->secstrings, size); + + /* Elf symbol section index */ + symndx = info->index.sym; + mod->klp_info->symndx = symndx; + + /* + * For livepatch modules, core_kallsyms.symtab is a complete + * copy of the original symbol table. Adjust sh_addr to point + * to core_kallsyms.symtab since the copy of the symtab in module + * init memory is freed at the end of do_init_module(). + */ + mod->klp_info->sechdrs[symndx].sh_addr = \ + (unsigned long) mod->core_kallsyms.symtab; + + return 0; + +free_sechdrs: + kfree(mod->klp_info->sechdrs); +free_info: + kfree(mod->klp_info); + return ret; +} + +static void free_module_elf(struct module *mod) +{ + kfree(mod->klp_info->sechdrs); + kfree(mod->klp_info->secstrings); + kfree(mod->klp_info); +} +#else /* !CONFIG_LIVEPATCH */ +static int copy_module_elf(struct module *mod, struct load_info *info) +{ + return 0; +} + +static void free_module_elf(struct module *mod) +{ +} +#endif /* CONFIG_LIVEPATCH */ + void __weak module_memfree(void *module_region) { vfree(module_region); @@ -2011,6 +2088,9 @@ static void free_module(struct module *mod) /* Free any allocated parameters. */ destroy_params(mod->kp, mod->num_kp); + if (is_livepatch_module(mod)) + free_module_elf(mod); + /* Now we can delete it from the lists */ mutex_lock(&module_mutex); /* Unlink carefully: kallsyms could be walking list. */ @@ -2126,6 +2206,10 @@ static int simplify_symbols(struct module *mod, const struct load_info *info) (long)sym[i].st_value); break; + case SHN_LIVEPATCH: + /* Livepatch symbols are resolved by livepatch */ + break; + case SHN_UNDEF: ksym = resolve_symbol_wait(mod, info, name); /* Ok if resolved. */ @@ -2174,6 +2258,10 @@ static int apply_relocations(struct module *mod, const struct load_info *info) if (!(info->sechdrs[infosec].sh_flags & SHF_ALLOC)) continue; + /* Livepatch relocation sections are applied by livepatch */ + if (info->sechdrs[i].sh_flags & SHF_RELA_LIVEPATCH) + continue; + if (info->sechdrs[i].sh_type == SHT_REL) err = apply_relocate(info->sechdrs, info->strtab, info->index.sym, i, mod); @@ -2469,7 +2557,7 @@ static void layout_symtab(struct module *mod, struct load_info *info) /* Compute total space required for the core symbols' strtab. */ for (ndst = i = 0; i < nsrc; i++) { - if (i == 0 || + if (i == 0 || is_livepatch_module(mod) || is_core_symbol(src+i, info->sechdrs, info->hdr->e_shnum, info->index.pcpu)) { strtab_size += strlen(&info->strtab[src[i].st_name])+1; @@ -2528,7 +2616,7 @@ static void add_kallsyms(struct module *mod, const struct load_info *info) mod->core_kallsyms.strtab = s = mod->core_layout.base + info->stroffs; src = mod->kallsyms->symtab; for (ndst = i = 0; i < mod->kallsyms->num_symtab; i++) { - if (i == 0 || + if (i == 0 || is_livepatch_module(mod) || is_core_symbol(src+i, info->sechdrs, info->hdr->e_shnum, info->index.pcpu)) { dst[ndst] = src[i]; @@ -2667,6 +2755,26 @@ static int copy_chunked_from_user(void *dst, const void __user *usrc, unsigned l return 0; } +#ifdef CONFIG_LIVEPATCH +static int find_livepatch_modinfo(struct module *mod, struct load_info *info) +{ + mod->klp = get_modinfo(info, "livepatch") ? true : false; + + return 0; +} +#else /* !CONFIG_LIVEPATCH */ +static int find_livepatch_modinfo(struct module *mod, struct load_info *info) +{ + if (get_modinfo(info, "livepatch")) { + pr_err("%s: module is marked as livepatch module, but livepatch support is disabled", + mod->name); + return -ENOEXEC; + } + + return 0; +} +#endif /* CONFIG_LIVEPATCH */ + /* Sets info->hdr and info->len. */ static int copy_module_from_user(const void __user *umod, unsigned long len, struct load_info *info) @@ -2821,6 +2929,10 @@ static int check_modinfo(struct module *mod, struct load_info *info, int flags) "is unknown, you have been warned.\n", mod->name); } + err = find_livepatch_modinfo(mod, info); + if (err) + return err; + /* Set up license info based on the info section */ set_license(mod, get_modinfo(info, "license")); @@ -3494,6 +3606,12 @@ static int load_module(struct load_info *info, const char __user *uargs, if (err < 0) goto coming_cleanup; + if (is_livepatch_module(mod)) { + err = copy_module_elf(mod, info); + if (err < 0) + goto sysfs_cleanup; + } + /* Get rid of temporary copy. */ free_copy(info); @@ -3502,11 +3620,12 @@ static int load_module(struct load_info *info, const char __user *uargs, return do_init_module(mod); + sysfs_cleanup: + mod_sysfs_teardown(mod); coming_cleanup: blocking_notifier_call_chain(&module_notify_list, MODULE_STATE_GOING, mod); klp_module_going(mod); - bug_cleanup: /* module_bug_cleanup needs module_mutex protection */ mutex_lock(&module_mutex); diff --git a/kernel/power/swap.c b/kernel/power/swap.c index 12cd989dadf6..160e1006640d 100644 --- a/kernel/power/swap.c +++ b/kernel/power/swap.c @@ -37,6 +37,14 @@ #define HIBERNATE_SIG "S1SUSPEND" /* + * When reading an {un,}compressed image, we may restore pages in place, + * in which case some architectures need these pages cleaning before they + * can be executed. We don't know which pages these may be, so clean the lot. + */ +static bool clean_pages_on_read; +static bool clean_pages_on_decompress; + +/* * The swap map is a data structure used for keeping track of each page * written to a swap partition. It consists of many swap_map_page * structures that contain each an array of MAP_PAGE_ENTRIES swap entries. @@ -241,6 +249,9 @@ static void hib_end_io(struct bio *bio) if (bio_data_dir(bio) == WRITE) put_page(page); + else if (clean_pages_on_read) + flush_icache_range((unsigned long)page_address(page), + (unsigned long)page_address(page) + PAGE_SIZE); if (bio->bi_error && !hb->error) hb->error = bio->bi_error; @@ -1049,6 +1060,7 @@ static int load_image(struct swap_map_handle *handle, hib_init_batch(&hb); + clean_pages_on_read = true; printk(KERN_INFO "PM: Loading image data pages (%u pages)...\n", nr_to_read); m = nr_to_read / 10; @@ -1124,6 +1136,10 @@ static int lzo_decompress_threadfn(void *data) d->unc_len = LZO_UNC_SIZE; d->ret = lzo1x_decompress_safe(d->cmp + LZO_HEADER, d->cmp_len, d->unc, &d->unc_len); + if (clean_pages_on_decompress) + flush_icache_range((unsigned long)d->unc, + (unsigned long)d->unc + d->unc_len); + atomic_set(&d->stop, 1); wake_up(&d->done); } @@ -1189,6 +1205,8 @@ static int load_image_lzo(struct swap_map_handle *handle, } memset(crc, 0, offsetof(struct crc_data, go)); + clean_pages_on_decompress = true; + /* * Start the decompression threads. */ diff --git a/kernel/rcu/Makefile b/kernel/rcu/Makefile index 032b2c015beb..18dfc485225c 100644 --- a/kernel/rcu/Makefile +++ b/kernel/rcu/Makefile @@ -5,6 +5,7 @@ KCOV_INSTRUMENT := n obj-y += update.o sync.o obj-$(CONFIG_SRCU) += srcu.o obj-$(CONFIG_RCU_TORTURE_TEST) += rcutorture.o +obj-$(CONFIG_RCU_PERF_TEST) += rcuperf.o obj-$(CONFIG_TREE_RCU) += tree.o obj-$(CONFIG_PREEMPT_RCU) += tree.o obj-$(CONFIG_TREE_RCU_TRACE) += tree_trace.o diff --git a/kernel/rcu/rcuperf.c b/kernel/rcu/rcuperf.c new file mode 100644 index 000000000000..3cee0d8393ed --- /dev/null +++ b/kernel/rcu/rcuperf.c @@ -0,0 +1,655 @@ +/* + * Read-Copy Update module-based performance-test facility + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, you can access it online at + * http://www.gnu.org/licenses/gpl-2.0.html. + * + * Copyright (C) IBM Corporation, 2015 + * + * Authors: Paul E. McKenney <paulmck@us.ibm.com> + */ +#include <linux/types.h> +#include <linux/kernel.h> +#include <linux/init.h> +#include <linux/module.h> +#include <linux/kthread.h> +#include <linux/err.h> +#include <linux/spinlock.h> +#include <linux/smp.h> +#include <linux/rcupdate.h> +#include <linux/interrupt.h> +#include <linux/sched.h> +#include <linux/atomic.h> +#include <linux/bitops.h> +#include <linux/completion.h> +#include <linux/moduleparam.h> +#include <linux/percpu.h> +#include <linux/notifier.h> +#include <linux/reboot.h> +#include <linux/freezer.h> +#include <linux/cpu.h> +#include <linux/delay.h> +#include <linux/stat.h> +#include <linux/srcu.h> +#include <linux/slab.h> +#include <asm/byteorder.h> +#include <linux/torture.h> +#include <linux/vmalloc.h> + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Paul E. McKenney <paulmck@linux.vnet.ibm.com>"); + +#define PERF_FLAG "-perf:" +#define PERFOUT_STRING(s) \ + pr_alert("%s" PERF_FLAG s "\n", perf_type) +#define VERBOSE_PERFOUT_STRING(s) \ + do { if (verbose) pr_alert("%s" PERF_FLAG " %s\n", perf_type, s); } while (0) +#define VERBOSE_PERFOUT_ERRSTRING(s) \ + do { if (verbose) pr_alert("%s" PERF_FLAG "!!! %s\n", perf_type, s); } while (0) + +torture_param(bool, gp_exp, true, "Use expedited GP wait primitives"); +torture_param(int, holdoff, 10, "Holdoff time before test start (s)"); +torture_param(int, nreaders, -1, "Number of RCU reader threads"); +torture_param(int, nwriters, -1, "Number of RCU updater threads"); +torture_param(bool, shutdown, false, "Shutdown at end of performance tests."); +torture_param(bool, verbose, true, "Enable verbose debugging printk()s"); + +static char *perf_type = "rcu"; +module_param(perf_type, charp, 0444); +MODULE_PARM_DESC(perf_type, "Type of RCU to performance-test (rcu, rcu_bh, ...)"); + +static int nrealreaders; +static int nrealwriters; +static struct task_struct **writer_tasks; +static struct task_struct **reader_tasks; +static struct task_struct *shutdown_task; + +static u64 **writer_durations; +static int *writer_n_durations; +static atomic_t n_rcu_perf_reader_started; +static atomic_t n_rcu_perf_writer_started; +static atomic_t n_rcu_perf_writer_finished; +static wait_queue_head_t shutdown_wq; +static u64 t_rcu_perf_writer_started; +static u64 t_rcu_perf_writer_finished; +static unsigned long b_rcu_perf_writer_started; +static unsigned long b_rcu_perf_writer_finished; + +static int rcu_perf_writer_state; +#define RTWS_INIT 0 +#define RTWS_EXP_SYNC 1 +#define RTWS_SYNC 2 +#define RTWS_IDLE 2 +#define RTWS_STOPPING 3 + +#define MAX_MEAS 10000 +#define MIN_MEAS 100 + +#if defined(MODULE) || defined(CONFIG_RCU_PERF_TEST_RUNNABLE) +#define RCUPERF_RUNNABLE_INIT 1 +#else +#define RCUPERF_RUNNABLE_INIT 0 +#endif +static int perf_runnable = RCUPERF_RUNNABLE_INIT; +module_param(perf_runnable, int, 0444); +MODULE_PARM_DESC(perf_runnable, "Start rcuperf at boot"); + +/* + * Operations vector for selecting different types of tests. + */ + +struct rcu_perf_ops { + int ptype; + void (*init)(void); + void (*cleanup)(void); + int (*readlock)(void); + void (*readunlock)(int idx); + unsigned long (*started)(void); + unsigned long (*completed)(void); + unsigned long (*exp_completed)(void); + void (*sync)(void); + void (*exp_sync)(void); + const char *name; +}; + +static struct rcu_perf_ops *cur_ops; + +/* + * Definitions for rcu perf testing. + */ + +static int rcu_perf_read_lock(void) __acquires(RCU) +{ + rcu_read_lock(); + return 0; +} + +static void rcu_perf_read_unlock(int idx) __releases(RCU) +{ + rcu_read_unlock(); +} + +static unsigned long __maybe_unused rcu_no_completed(void) +{ + return 0; +} + +static void rcu_sync_perf_init(void) +{ +} + +static struct rcu_perf_ops rcu_ops = { + .ptype = RCU_FLAVOR, + .init = rcu_sync_perf_init, + .readlock = rcu_perf_read_lock, + .readunlock = rcu_perf_read_unlock, + .started = rcu_batches_started, + .completed = rcu_batches_completed, + .exp_completed = rcu_exp_batches_completed, + .sync = synchronize_rcu, + .exp_sync = synchronize_rcu_expedited, + .name = "rcu" +}; + +/* + * Definitions for rcu_bh perf testing. + */ + +static int rcu_bh_perf_read_lock(void) __acquires(RCU_BH) +{ + rcu_read_lock_bh(); + return 0; +} + +static void rcu_bh_perf_read_unlock(int idx) __releases(RCU_BH) +{ + rcu_read_unlock_bh(); +} + +static struct rcu_perf_ops rcu_bh_ops = { + .ptype = RCU_BH_FLAVOR, + .init = rcu_sync_perf_init, + .readlock = rcu_bh_perf_read_lock, + .readunlock = rcu_bh_perf_read_unlock, + .started = rcu_batches_started_bh, + .completed = rcu_batches_completed_bh, + .exp_completed = rcu_exp_batches_completed_sched, + .sync = synchronize_rcu_bh, + .exp_sync = synchronize_rcu_bh_expedited, + .name = "rcu_bh" +}; + +/* + * Definitions for srcu perf testing. + */ + +DEFINE_STATIC_SRCU(srcu_ctl_perf); +static struct srcu_struct *srcu_ctlp = &srcu_ctl_perf; + +static int srcu_perf_read_lock(void) __acquires(srcu_ctlp) +{ + return srcu_read_lock(srcu_ctlp); +} + +static void srcu_perf_read_unlock(int idx) __releases(srcu_ctlp) +{ + srcu_read_unlock(srcu_ctlp, idx); +} + +static unsigned long srcu_perf_completed(void) +{ + return srcu_batches_completed(srcu_ctlp); +} + +static void srcu_perf_synchronize(void) +{ + synchronize_srcu(srcu_ctlp); +} + +static void srcu_perf_synchronize_expedited(void) +{ + synchronize_srcu_expedited(srcu_ctlp); +} + +static struct rcu_perf_ops srcu_ops = { + .ptype = SRCU_FLAVOR, + .init = rcu_sync_perf_init, + .readlock = srcu_perf_read_lock, + .readunlock = srcu_perf_read_unlock, + .started = NULL, + .completed = srcu_perf_completed, + .exp_completed = srcu_perf_completed, + .sync = srcu_perf_synchronize, + .exp_sync = srcu_perf_synchronize_expedited, + .name = "srcu" +}; + +/* + * Definitions for sched perf testing. + */ + +static int sched_perf_read_lock(void) +{ + preempt_disable(); + return 0; +} + +static void sched_perf_read_unlock(int idx) +{ + preempt_enable(); +} + +static struct rcu_perf_ops sched_ops = { + .ptype = RCU_SCHED_FLAVOR, + .init = rcu_sync_perf_init, + .readlock = sched_perf_read_lock, + .readunlock = sched_perf_read_unlock, + .started = rcu_batches_started_sched, + .completed = rcu_batches_completed_sched, + .exp_completed = rcu_exp_batches_completed_sched, + .sync = synchronize_sched, + .exp_sync = synchronize_sched_expedited, + .name = "sched" +}; + +#ifdef CONFIG_TASKS_RCU + +/* + * Definitions for RCU-tasks perf testing. + */ + +static int tasks_perf_read_lock(void) +{ + return 0; +} + +static void tasks_perf_read_unlock(int idx) +{ +} + +static struct rcu_perf_ops tasks_ops = { + .ptype = RCU_TASKS_FLAVOR, + .init = rcu_sync_perf_init, + .readlock = tasks_perf_read_lock, + .readunlock = tasks_perf_read_unlock, + .started = rcu_no_completed, + .completed = rcu_no_completed, + .sync = synchronize_rcu_tasks, + .exp_sync = synchronize_rcu_tasks, + .name = "tasks" +}; + +#define RCUPERF_TASKS_OPS &tasks_ops, + +static bool __maybe_unused torturing_tasks(void) +{ + return cur_ops == &tasks_ops; +} + +#else /* #ifdef CONFIG_TASKS_RCU */ + +#define RCUPERF_TASKS_OPS + +static bool __maybe_unused torturing_tasks(void) +{ + return false; +} + +#endif /* #else #ifdef CONFIG_TASKS_RCU */ + +/* + * If performance tests complete, wait for shutdown to commence. + */ +static void rcu_perf_wait_shutdown(void) +{ + cond_resched_rcu_qs(); + if (atomic_read(&n_rcu_perf_writer_finished) < nrealwriters) + return; + while (!torture_must_stop()) + schedule_timeout_uninterruptible(1); +} + +/* + * RCU perf reader kthread. Repeatedly does empty RCU read-side + * critical section, minimizing update-side interference. + */ +static int +rcu_perf_reader(void *arg) +{ + unsigned long flags; + int idx; + long me = (long)arg; + + VERBOSE_PERFOUT_STRING("rcu_perf_reader task started"); + set_cpus_allowed_ptr(current, cpumask_of(me % nr_cpu_ids)); + set_user_nice(current, MAX_NICE); + atomic_inc(&n_rcu_perf_reader_started); + + do { + local_irq_save(flags); + idx = cur_ops->readlock(); + cur_ops->readunlock(idx); + local_irq_restore(flags); + rcu_perf_wait_shutdown(); + } while (!torture_must_stop()); + torture_kthread_stopping("rcu_perf_reader"); + return 0; +} + +/* + * RCU perf writer kthread. Repeatedly does a grace period. + */ +static int +rcu_perf_writer(void *arg) +{ + int i = 0; + int i_max; + long me = (long)arg; + struct sched_param sp; + bool started = false, done = false, alldone = false; + u64 t; + u64 *wdp; + u64 *wdpp = writer_durations[me]; + + VERBOSE_PERFOUT_STRING("rcu_perf_writer task started"); + WARN_ON(rcu_gp_is_expedited() && !rcu_gp_is_normal() && !gp_exp); + WARN_ON(rcu_gp_is_normal() && gp_exp); + WARN_ON(!wdpp); + set_cpus_allowed_ptr(current, cpumask_of(me % nr_cpu_ids)); + sp.sched_priority = 1; + sched_setscheduler_nocheck(current, SCHED_FIFO, &sp); + + if (holdoff) + schedule_timeout_uninterruptible(holdoff * HZ); + + t = ktime_get_mono_fast_ns(); + if (atomic_inc_return(&n_rcu_perf_writer_started) >= nrealwriters) { + t_rcu_perf_writer_started = t; + if (gp_exp) { + b_rcu_perf_writer_started = + cur_ops->exp_completed() / 2; + } else { + b_rcu_perf_writer_started = + cur_ops->completed(); + } + } + + do { + wdp = &wdpp[i]; + *wdp = ktime_get_mono_fast_ns(); + if (gp_exp) { + rcu_perf_writer_state = RTWS_EXP_SYNC; + cur_ops->exp_sync(); + } else { + rcu_perf_writer_state = RTWS_SYNC; + cur_ops->sync(); + } + rcu_perf_writer_state = RTWS_IDLE; + t = ktime_get_mono_fast_ns(); + *wdp = t - *wdp; + i_max = i; + if (!started && + atomic_read(&n_rcu_perf_writer_started) >= nrealwriters) + started = true; + if (!done && i >= MIN_MEAS) { + done = true; + sp.sched_priority = 0; + sched_setscheduler_nocheck(current, + SCHED_NORMAL, &sp); + pr_alert("%s" PERF_FLAG + "rcu_perf_writer %ld has %d measurements\n", + perf_type, me, MIN_MEAS); + if (atomic_inc_return(&n_rcu_perf_writer_finished) >= + nrealwriters) { + schedule_timeout_interruptible(10); + rcu_ftrace_dump(DUMP_ALL); + PERFOUT_STRING("Test complete"); + t_rcu_perf_writer_finished = t; + if (gp_exp) { + b_rcu_perf_writer_finished = + cur_ops->exp_completed() / 2; + } else { + b_rcu_perf_writer_finished = + cur_ops->completed(); + } + if (shutdown) { + smp_mb(); /* Assign before wake. */ + wake_up(&shutdown_wq); + } + } + } + if (done && !alldone && + atomic_read(&n_rcu_perf_writer_finished) >= nrealwriters) + alldone = true; + if (started && !alldone && i < MAX_MEAS - 1) + i++; + rcu_perf_wait_shutdown(); + } while (!torture_must_stop()); + rcu_perf_writer_state = RTWS_STOPPING; + writer_n_durations[me] = i_max; + torture_kthread_stopping("rcu_perf_writer"); + return 0; +} + +static inline void +rcu_perf_print_module_parms(struct rcu_perf_ops *cur_ops, const char *tag) +{ + pr_alert("%s" PERF_FLAG + "--- %s: nreaders=%d nwriters=%d verbose=%d shutdown=%d\n", + perf_type, tag, nrealreaders, nrealwriters, verbose, shutdown); +} + +static void +rcu_perf_cleanup(void) +{ + int i; + int j; + int ngps = 0; + u64 *wdp; + u64 *wdpp; + + if (torture_cleanup_begin()) + return; + + if (reader_tasks) { + for (i = 0; i < nrealreaders; i++) + torture_stop_kthread(rcu_perf_reader, + reader_tasks[i]); + kfree(reader_tasks); + } + + if (writer_tasks) { + for (i = 0; i < nrealwriters; i++) { + torture_stop_kthread(rcu_perf_writer, + writer_tasks[i]); + if (!writer_n_durations) + continue; + j = writer_n_durations[i]; + pr_alert("%s%s writer %d gps: %d\n", + perf_type, PERF_FLAG, i, j); + ngps += j; + } + pr_alert("%s%s start: %llu end: %llu duration: %llu gps: %d batches: %ld\n", + perf_type, PERF_FLAG, + t_rcu_perf_writer_started, t_rcu_perf_writer_finished, + t_rcu_perf_writer_finished - + t_rcu_perf_writer_started, + ngps, + b_rcu_perf_writer_finished - + b_rcu_perf_writer_started); + for (i = 0; i < nrealwriters; i++) { + if (!writer_durations) + break; + if (!writer_n_durations) + continue; + wdpp = writer_durations[i]; + if (!wdpp) + continue; + for (j = 0; j <= writer_n_durations[i]; j++) { + wdp = &wdpp[j]; + pr_alert("%s%s %4d writer-duration: %5d %llu\n", + perf_type, PERF_FLAG, + i, j, *wdp); + if (j % 100 == 0) + schedule_timeout_uninterruptible(1); + } + kfree(writer_durations[i]); + } + kfree(writer_tasks); + kfree(writer_durations); + kfree(writer_n_durations); + } + + /* Do flavor-specific cleanup operations. */ + if (cur_ops->cleanup != NULL) + cur_ops->cleanup(); + + torture_cleanup_end(); +} + +/* + * Return the number if non-negative. If -1, the number of CPUs. + * If less than -1, that much less than the number of CPUs, but + * at least one. + */ +static int compute_real(int n) +{ + int nr; + + if (n >= 0) { + nr = n; + } else { + nr = num_online_cpus() + 1 + n; + if (nr <= 0) + nr = 1; + } + return nr; +} + +/* + * RCU perf shutdown kthread. Just waits to be awakened, then shuts + * down system. + */ +static int +rcu_perf_shutdown(void *arg) +{ + do { + wait_event(shutdown_wq, + atomic_read(&n_rcu_perf_writer_finished) >= + nrealwriters); + } while (atomic_read(&n_rcu_perf_writer_finished) < nrealwriters); + smp_mb(); /* Wake before output. */ + rcu_perf_cleanup(); + kernel_power_off(); + return -EINVAL; +} + +static int __init +rcu_perf_init(void) +{ + long i; + int firsterr = 0; + static struct rcu_perf_ops *perf_ops[] = { + &rcu_ops, &rcu_bh_ops, &srcu_ops, &sched_ops, + RCUPERF_TASKS_OPS + }; + + if (!torture_init_begin(perf_type, verbose, &perf_runnable)) + return -EBUSY; + + /* Process args and tell the world that the perf'er is on the job. */ + for (i = 0; i < ARRAY_SIZE(perf_ops); i++) { + cur_ops = perf_ops[i]; + if (strcmp(perf_type, cur_ops->name) == 0) + break; + } + if (i == ARRAY_SIZE(perf_ops)) { + pr_alert("rcu-perf: invalid perf type: \"%s\"\n", + perf_type); + pr_alert("rcu-perf types:"); + for (i = 0; i < ARRAY_SIZE(perf_ops); i++) + pr_alert(" %s", perf_ops[i]->name); + pr_alert("\n"); + firsterr = -EINVAL; + goto unwind; + } + if (cur_ops->init) + cur_ops->init(); + + nrealwriters = compute_real(nwriters); + nrealreaders = compute_real(nreaders); + atomic_set(&n_rcu_perf_reader_started, 0); + atomic_set(&n_rcu_perf_writer_started, 0); + atomic_set(&n_rcu_perf_writer_finished, 0); + rcu_perf_print_module_parms(cur_ops, "Start of test"); + + /* Start up the kthreads. */ + + if (shutdown) { + init_waitqueue_head(&shutdown_wq); + firsterr = torture_create_kthread(rcu_perf_shutdown, NULL, + shutdown_task); + if (firsterr) + goto unwind; + schedule_timeout_uninterruptible(1); + } + reader_tasks = kcalloc(nrealreaders, sizeof(reader_tasks[0]), + GFP_KERNEL); + if (reader_tasks == NULL) { + VERBOSE_PERFOUT_ERRSTRING("out of memory"); + firsterr = -ENOMEM; + goto unwind; + } + for (i = 0; i < nrealreaders; i++) { + firsterr = torture_create_kthread(rcu_perf_reader, (void *)i, + reader_tasks[i]); + if (firsterr) + goto unwind; + } + while (atomic_read(&n_rcu_perf_reader_started) < nrealreaders) + schedule_timeout_uninterruptible(1); + writer_tasks = kcalloc(nrealwriters, sizeof(reader_tasks[0]), + GFP_KERNEL); + writer_durations = kcalloc(nrealwriters, sizeof(*writer_durations), + GFP_KERNEL); + writer_n_durations = + kcalloc(nrealwriters, sizeof(*writer_n_durations), + GFP_KERNEL); + if (!writer_tasks || !writer_durations || !writer_n_durations) { + VERBOSE_PERFOUT_ERRSTRING("out of memory"); + firsterr = -ENOMEM; + goto unwind; + } + for (i = 0; i < nrealwriters; i++) { + writer_durations[i] = + kcalloc(MAX_MEAS, sizeof(*writer_durations[i]), + GFP_KERNEL); + if (!writer_durations[i]) + goto unwind; + firsterr = torture_create_kthread(rcu_perf_writer, (void *)i, + writer_tasks[i]); + if (firsterr) + goto unwind; + } + torture_init_end(); + return 0; + +unwind: + torture_init_end(); + rcu_perf_cleanup(); + return firsterr; +} + +module_init(rcu_perf_init); +module_exit(rcu_perf_cleanup); diff --git a/kernel/rcu/rcutorture.c b/kernel/rcu/rcutorture.c index 250ea67c1615..084a28a732eb 100644 --- a/kernel/rcu/rcutorture.c +++ b/kernel/rcu/rcutorture.c @@ -130,8 +130,8 @@ static struct rcu_torture __rcu *rcu_torture_current; static unsigned long rcu_torture_current_version; static struct rcu_torture rcu_tortures[10 * RCU_TORTURE_PIPE_LEN]; static DEFINE_SPINLOCK(rcu_torture_lock); -static DEFINE_PER_CPU(long [RCU_TORTURE_PIPE_LEN + 1], rcu_torture_count) = { 0 }; -static DEFINE_PER_CPU(long [RCU_TORTURE_PIPE_LEN + 1], rcu_torture_batch) = { 0 }; +static DEFINE_PER_CPU(long [RCU_TORTURE_PIPE_LEN + 1], rcu_torture_count); +static DEFINE_PER_CPU(long [RCU_TORTURE_PIPE_LEN + 1], rcu_torture_batch); static atomic_t rcu_torture_wcount[RCU_TORTURE_PIPE_LEN + 1]; static atomic_t n_rcu_torture_alloc; static atomic_t n_rcu_torture_alloc_fail; @@ -916,7 +916,7 @@ rcu_torture_fqs(void *arg) static int rcu_torture_writer(void *arg) { - bool can_expedite = !rcu_gp_is_expedited(); + bool can_expedite = !rcu_gp_is_expedited() && !rcu_gp_is_normal(); int expediting = 0; unsigned long gp_snap; bool gp_cond1 = gp_cond, gp_exp1 = gp_exp, gp_normal1 = gp_normal; @@ -932,7 +932,7 @@ rcu_torture_writer(void *arg) VERBOSE_TOROUT_STRING("rcu_torture_writer task started"); if (!can_expedite) { pr_alert("%s" TORTURE_FLAG - " Grace periods expedited from boot/sysfs for %s,\n", + " GP expediting controlled from boot/sysfs for %s,\n", torture_type, cur_ops->name); pr_alert("%s" TORTURE_FLAG " Disabled dynamic grace-period expediting.\n", @@ -1082,17 +1082,6 @@ rcu_torture_fakewriter(void *arg) return 0; } -static void rcutorture_trace_dump(void) -{ - static atomic_t beenhere = ATOMIC_INIT(0); - - if (atomic_read(&beenhere)) - return; - if (atomic_xchg(&beenhere, 1) != 0) - return; - ftrace_dump(DUMP_ALL); -} - /* * RCU torture reader from timer handler. Dereferences rcu_torture_current, * incrementing the corresponding element of the pipeline array. The @@ -1142,7 +1131,7 @@ static void rcu_torture_timer(unsigned long unused) if (pipe_count > 1) { do_trace_rcu_torture_read(cur_ops->name, &p->rtort_rcu, ts, started, completed); - rcutorture_trace_dump(); + rcu_ftrace_dump(DUMP_ALL); } __this_cpu_inc(rcu_torture_count[pipe_count]); completed = completed - started; @@ -1215,7 +1204,7 @@ rcu_torture_reader(void *arg) if (pipe_count > 1) { do_trace_rcu_torture_read(cur_ops->name, &p->rtort_rcu, ts, started, completed); - rcutorture_trace_dump(); + rcu_ftrace_dump(DUMP_ALL); } __this_cpu_inc(rcu_torture_count[pipe_count]); completed = completed - started; @@ -1333,7 +1322,7 @@ rcu_torture_stats_print(void) rcu_torture_writer_state, gpnum, completed, flags); show_rcu_gp_kthreads(); - rcutorture_trace_dump(); + rcu_ftrace_dump(DUMP_ALL); } rtcv_snap = rcu_torture_current_version; } @@ -1489,7 +1478,9 @@ static int rcu_torture_barrier_cbs(void *arg) * The above smp_load_acquire() ensures barrier_phase load * is ordered before the folloiwng ->call(). */ + local_irq_disable(); /* Just to test no-irq call_rcu(). */ cur_ops->call(&rcu, rcu_torture_barrier_cbf); + local_irq_enable(); if (atomic_dec_and_test(&barrier_cbs_count)) wake_up(&barrier_wq); } while (!torture_must_stop()); @@ -1596,7 +1587,7 @@ static int rcutorture_cpu_notify(struct notifier_block *self, { long cpu = (long)hcpu; - switch (action) { + switch (action & ~CPU_TASKS_FROZEN) { case CPU_ONLINE: case CPU_DOWN_FAILED: (void)rcutorture_booster_init(cpu); diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c index 9a535a86e732..c7f1bc4f817c 100644 --- a/kernel/rcu/tree.c +++ b/kernel/rcu/tree.c @@ -102,6 +102,8 @@ struct rcu_state sname##_state = { \ .barrier_mutex = __MUTEX_INITIALIZER(sname##_state.barrier_mutex), \ .name = RCU_STATE_NAME(sname), \ .abbr = sabbr, \ + .exp_mutex = __MUTEX_INITIALIZER(sname##_state.exp_mutex), \ + .exp_wake_mutex = __MUTEX_INITIALIZER(sname##_state.exp_wake_mutex), \ } RCU_STATE_INITIALIZER(rcu_sched, 's', call_rcu_sched); @@ -370,6 +372,21 @@ void rcu_all_qs(void) rcu_momentary_dyntick_idle(); local_irq_restore(flags); } + if (unlikely(raw_cpu_read(rcu_sched_data.cpu_no_qs.b.exp))) { + /* + * Yes, we just checked a per-CPU variable with preemption + * enabled, so we might be migrated to some other CPU at + * this point. That is OK because in that case, the + * migration will supply the needed quiescent state. + * We might end up needlessly disabling preemption and + * invoking rcu_sched_qs() on the destination CPU, but + * the probability and cost are both quite low, so this + * should not be a problem in practice. + */ + preempt_disable(); + rcu_sched_qs(); + preempt_enable(); + } this_cpu_inc(rcu_qs_ctr); barrier(); /* Avoid RCU read-side critical sections leaking up. */ } @@ -385,9 +402,11 @@ module_param(qlowmark, long, 0444); static ulong jiffies_till_first_fqs = ULONG_MAX; static ulong jiffies_till_next_fqs = ULONG_MAX; +static bool rcu_kick_kthreads; module_param(jiffies_till_first_fqs, ulong, 0644); module_param(jiffies_till_next_fqs, ulong, 0644); +module_param(rcu_kick_kthreads, bool, 0644); /* * How long the grace period must be before we start recruiting @@ -460,6 +479,28 @@ unsigned long rcu_batches_completed_bh(void) EXPORT_SYMBOL_GPL(rcu_batches_completed_bh); /* + * Return the number of RCU expedited batches completed thus far for + * debug & stats. Odd numbers mean that a batch is in progress, even + * numbers mean idle. The value returned will thus be roughly double + * the cumulative batches since boot. + */ +unsigned long rcu_exp_batches_completed(void) +{ + return rcu_state_p->expedited_sequence; +} +EXPORT_SYMBOL_GPL(rcu_exp_batches_completed); + +/* + * Return the number of RCU-sched expedited batches completed thus far + * for debug & stats. Similar to rcu_exp_batches_completed(). + */ +unsigned long rcu_exp_batches_completed_sched(void) +{ + return rcu_sched_state.expedited_sequence; +} +EXPORT_SYMBOL_GPL(rcu_exp_batches_completed_sched); + +/* * Force a quiescent state. */ void rcu_force_quiescent_state(void) @@ -637,7 +678,7 @@ static void rcu_eqs_enter_common(long long oldval, bool user) idle_task(smp_processor_id()); trace_rcu_dyntick(TPS("Error on entry: not idle task"), oldval, 0); - ftrace_dump(DUMP_ORIG); + rcu_ftrace_dump(DUMP_ORIG); WARN_ONCE(1, "Current pid: %d comm: %s / Idle pid: %d comm: %s", current->pid, current->comm, idle->pid, idle->comm); /* must be idle task! */ @@ -799,7 +840,7 @@ static void rcu_eqs_exit_common(long long oldval, int user) trace_rcu_dyntick(TPS("Error on exit: not idle task"), oldval, rdtp->dynticks_nesting); - ftrace_dump(DUMP_ORIG); + rcu_ftrace_dump(DUMP_ORIG); WARN_ONCE(1, "Current pid: %d comm: %s / Idle pid: %d comm: %s", current->pid, current->comm, idle->pid, idle->comm); /* must be idle task! */ @@ -1224,8 +1265,10 @@ static void rcu_check_gp_kthread_starvation(struct rcu_state *rsp) rsp->gp_flags, gp_state_getname(rsp->gp_state), rsp->gp_state, rsp->gp_kthread ? rsp->gp_kthread->state : ~0); - if (rsp->gp_kthread) + if (rsp->gp_kthread) { sched_show_task(rsp->gp_kthread); + wake_up_process(rsp->gp_kthread); + } } } @@ -1249,6 +1292,25 @@ static void rcu_dump_cpu_stacks(struct rcu_state *rsp) } } +/* + * If too much time has passed in the current grace period, and if + * so configured, go kick the relevant kthreads. + */ +static void rcu_stall_kick_kthreads(struct rcu_state *rsp) +{ + unsigned long j; + + if (!rcu_kick_kthreads) + return; + j = READ_ONCE(rsp->jiffies_kick_kthreads); + if (time_after(jiffies, j) && rsp->gp_kthread) { + WARN_ONCE(1, "Kicking %s grace-period kthread\n", rsp->name); + rcu_ftrace_dump(DUMP_ALL); + wake_up_process(rsp->gp_kthread); + WRITE_ONCE(rsp->jiffies_kick_kthreads, j + HZ); + } +} + static void print_other_cpu_stall(struct rcu_state *rsp, unsigned long gpnum) { int cpu; @@ -1260,6 +1322,11 @@ static void print_other_cpu_stall(struct rcu_state *rsp, unsigned long gpnum) struct rcu_node *rnp = rcu_get_root(rsp); long totqlen = 0; + /* Kick and suppress, if so configured. */ + rcu_stall_kick_kthreads(rsp); + if (rcu_cpu_stall_suppress) + return; + /* Only let one CPU complain about others per time interval. */ raw_spin_lock_irqsave_rcu_node(rnp, flags); @@ -1333,6 +1400,11 @@ static void print_cpu_stall(struct rcu_state *rsp) struct rcu_node *rnp = rcu_get_root(rsp); long totqlen = 0; + /* Kick and suppress, if so configured. */ + rcu_stall_kick_kthreads(rsp); + if (rcu_cpu_stall_suppress) + return; + /* * OK, time to rat on ourselves... * See Documentation/RCU/stallwarn.txt for info on how to debug @@ -1377,8 +1449,10 @@ static void check_cpu_stall(struct rcu_state *rsp, struct rcu_data *rdp) unsigned long js; struct rcu_node *rnp; - if (rcu_cpu_stall_suppress || !rcu_gp_in_progress(rsp)) + if ((rcu_cpu_stall_suppress && !rcu_kick_kthreads) || + !rcu_gp_in_progress(rsp)) return; + rcu_stall_kick_kthreads(rsp); j = jiffies; /* @@ -2117,8 +2191,11 @@ static int __noreturn rcu_gp_kthread(void *arg) } ret = 0; for (;;) { - if (!ret) + if (!ret) { rsp->jiffies_force_qs = jiffies + j; + WRITE_ONCE(rsp->jiffies_kick_kthreads, + jiffies + 3 * j); + } trace_rcu_grace_period(rsp->name, READ_ONCE(rsp->gpnum), TPS("fqswait")); @@ -2144,6 +2221,15 @@ static int __noreturn rcu_gp_kthread(void *arg) TPS("fqsend")); cond_resched_rcu_qs(); WRITE_ONCE(rsp->gp_activity, jiffies); + ret = 0; /* Force full wait till next FQS. */ + j = jiffies_till_next_fqs; + if (j > HZ) { + j = HZ; + jiffies_till_next_fqs = HZ; + } else if (j < 1) { + j = 1; + jiffies_till_next_fqs = 1; + } } else { /* Deal with stray signal. */ cond_resched_rcu_qs(); @@ -2152,14 +2238,12 @@ static int __noreturn rcu_gp_kthread(void *arg) trace_rcu_grace_period(rsp->name, READ_ONCE(rsp->gpnum), TPS("fqswaitsig")); - } - j = jiffies_till_next_fqs; - if (j > HZ) { - j = HZ; - jiffies_till_next_fqs = HZ; - } else if (j < 1) { - j = 1; - jiffies_till_next_fqs = 1; + ret = 1; /* Keep old FQS timing. */ + j = jiffies; + if (time_after(jiffies, rsp->jiffies_force_qs)) + j = 1; + else + j = rsp->jiffies_force_qs - j; } } @@ -3376,8 +3460,12 @@ static void rcu_exp_gp_seq_end(struct rcu_state *rsp) } static unsigned long rcu_exp_gp_seq_snap(struct rcu_state *rsp) { + unsigned long s; + smp_mb(); /* Caller's modifications seen first by other CPUs. */ - return rcu_seq_snap(&rsp->expedited_sequence); + s = rcu_seq_snap(&rsp->expedited_sequence); + trace_rcu_exp_grace_period(rsp->name, s, TPS("snap")); + return s; } static bool rcu_exp_gp_seq_done(struct rcu_state *rsp, unsigned long s) { @@ -3469,7 +3557,7 @@ static void __maybe_unused sync_exp_reset_tree(struct rcu_state *rsp) * for the current expedited grace period. Works only for preemptible * RCU -- other RCU implementation use other means. * - * Caller must hold the root rcu_node's exp_funnel_mutex. + * Caller must hold the rcu_state's exp_mutex. */ static int sync_rcu_preempt_exp_done(struct rcu_node *rnp) { @@ -3485,8 +3573,8 @@ static int sync_rcu_preempt_exp_done(struct rcu_node *rnp) * recursively up the tree. (Calm down, calm down, we do the recursion * iteratively!) * - * Caller must hold the root rcu_node's exp_funnel_mutex and the - * specified rcu_node structure's ->lock. + * Caller must hold the rcu_state's exp_mutex and the specified rcu_node + * structure's ->lock. */ static void __rcu_report_exp_rnp(struct rcu_state *rsp, struct rcu_node *rnp, bool wake, unsigned long flags) @@ -3523,7 +3611,7 @@ static void __rcu_report_exp_rnp(struct rcu_state *rsp, struct rcu_node *rnp, * Report expedited quiescent state for specified node. This is a * lock-acquisition wrapper function for __rcu_report_exp_rnp(). * - * Caller must hold the root rcu_node's exp_funnel_mutex. + * Caller must hold the rcu_state's exp_mutex. */ static void __maybe_unused rcu_report_exp_rnp(struct rcu_state *rsp, struct rcu_node *rnp, bool wake) @@ -3536,8 +3624,8 @@ static void __maybe_unused rcu_report_exp_rnp(struct rcu_state *rsp, /* * Report expedited quiescent state for multiple CPUs, all covered by the - * specified leaf rcu_node structure. Caller must hold the root - * rcu_node's exp_funnel_mutex. + * specified leaf rcu_node structure. Caller must hold the rcu_state's + * exp_mutex. */ static void rcu_report_exp_cpu_mult(struct rcu_state *rsp, struct rcu_node *rnp, unsigned long mask, bool wake) @@ -3555,7 +3643,6 @@ static void rcu_report_exp_cpu_mult(struct rcu_state *rsp, struct rcu_node *rnp, /* * Report expedited quiescent state for specified rcu_data (CPU). - * Caller must hold the root rcu_node's exp_funnel_mutex. */ static void rcu_report_exp_rdp(struct rcu_state *rsp, struct rcu_data *rdp, bool wake) @@ -3564,15 +3651,11 @@ static void rcu_report_exp_rdp(struct rcu_state *rsp, struct rcu_data *rdp, } /* Common code for synchronize_{rcu,sched}_expedited() work-done checking. */ -static bool sync_exp_work_done(struct rcu_state *rsp, struct rcu_node *rnp, - struct rcu_data *rdp, - atomic_long_t *stat, unsigned long s) +static bool sync_exp_work_done(struct rcu_state *rsp, atomic_long_t *stat, + unsigned long s) { if (rcu_exp_gp_seq_done(rsp, s)) { - if (rnp) - mutex_unlock(&rnp->exp_funnel_mutex); - else if (rdp) - mutex_unlock(&rdp->exp_funnel_mutex); + trace_rcu_exp_grace_period(rsp->name, s, TPS("done")); /* Ensure test happens before caller kfree(). */ smp_mb__before_atomic(); /* ^^^ */ atomic_long_inc(stat); @@ -3582,59 +3665,65 @@ static bool sync_exp_work_done(struct rcu_state *rsp, struct rcu_node *rnp, } /* - * Funnel-lock acquisition for expedited grace periods. Returns a - * pointer to the root rcu_node structure, or NULL if some other - * task did the expedited grace period for us. + * Funnel-lock acquisition for expedited grace periods. Returns true + * if some other task completed an expedited grace period that this task + * can piggy-back on, and with no mutex held. Otherwise, returns false + * with the mutex held, indicating that the caller must actually do the + * expedited grace period. */ -static struct rcu_node *exp_funnel_lock(struct rcu_state *rsp, unsigned long s) +static bool exp_funnel_lock(struct rcu_state *rsp, unsigned long s) { struct rcu_data *rdp = per_cpu_ptr(rsp->rda, raw_smp_processor_id()); - struct rcu_node *rnp0; - struct rcu_node *rnp1 = NULL; + struct rcu_node *rnp = rdp->mynode; + struct rcu_node *rnp_root = rcu_get_root(rsp); + + /* Low-contention fastpath. */ + if (ULONG_CMP_LT(READ_ONCE(rnp->exp_seq_rq), s) && + (rnp == rnp_root || + ULONG_CMP_LT(READ_ONCE(rnp_root->exp_seq_rq), s)) && + !mutex_is_locked(&rsp->exp_mutex) && + mutex_trylock(&rsp->exp_mutex)) + goto fastpath; /* - * First try directly acquiring the root lock in order to reduce - * latency in the common case where expedited grace periods are - * rare. We check mutex_is_locked() to avoid pathological levels of - * memory contention on ->exp_funnel_mutex in the heavy-load case. + * Each pass through the following loop works its way up + * the rcu_node tree, returning if others have done the work or + * otherwise falls through to acquire rsp->exp_mutex. The mapping + * from CPU to rcu_node structure can be inexact, as it is just + * promoting locality and is not strictly needed for correctness. */ - rnp0 = rcu_get_root(rsp); - if (!mutex_is_locked(&rnp0->exp_funnel_mutex)) { - if (mutex_trylock(&rnp0->exp_funnel_mutex)) { - if (sync_exp_work_done(rsp, rnp0, NULL, - &rdp->expedited_workdone0, s)) - return NULL; - return rnp0; + for (; rnp != NULL; rnp = rnp->parent) { + if (sync_exp_work_done(rsp, &rdp->exp_workdone1, s)) + return true; + + /* Work not done, either wait here or go up. */ + spin_lock(&rnp->exp_lock); + if (ULONG_CMP_GE(rnp->exp_seq_rq, s)) { + + /* Someone else doing GP, so wait for them. */ + spin_unlock(&rnp->exp_lock); + trace_rcu_exp_funnel_lock(rsp->name, rnp->level, + rnp->grplo, rnp->grphi, + TPS("wait")); + wait_event(rnp->exp_wq[(s >> 1) & 0x3], + sync_exp_work_done(rsp, + &rdp->exp_workdone2, s)); + return true; } + rnp->exp_seq_rq = s; /* Followers can wait on us. */ + spin_unlock(&rnp->exp_lock); + trace_rcu_exp_funnel_lock(rsp->name, rnp->level, rnp->grplo, + rnp->grphi, TPS("nxtlvl")); } - - /* - * Each pass through the following loop works its way - * up the rcu_node tree, returning if others have done the - * work or otherwise falls through holding the root rnp's - * ->exp_funnel_mutex. The mapping from CPU to rcu_node structure - * can be inexact, as it is just promoting locality and is not - * strictly needed for correctness. - */ - if (sync_exp_work_done(rsp, NULL, NULL, &rdp->expedited_workdone1, s)) - return NULL; - mutex_lock(&rdp->exp_funnel_mutex); - rnp0 = rdp->mynode; - for (; rnp0 != NULL; rnp0 = rnp0->parent) { - if (sync_exp_work_done(rsp, rnp1, rdp, - &rdp->expedited_workdone2, s)) - return NULL; - mutex_lock(&rnp0->exp_funnel_mutex); - if (rnp1) - mutex_unlock(&rnp1->exp_funnel_mutex); - else - mutex_unlock(&rdp->exp_funnel_mutex); - rnp1 = rnp0; + mutex_lock(&rsp->exp_mutex); +fastpath: + if (sync_exp_work_done(rsp, &rdp->exp_workdone3, s)) { + mutex_unlock(&rsp->exp_mutex); + return true; } - if (sync_exp_work_done(rsp, rnp1, rdp, - &rdp->expedited_workdone3, s)) - return NULL; - return rnp1; + rcu_exp_gp_seq_start(rsp); + trace_rcu_exp_grace_period(rsp->name, s, TPS("start")); + return false; } /* Invoked on each online non-idle CPU for expedited quiescent state. */ @@ -3649,6 +3738,11 @@ static void sync_sched_exp_handler(void *data) if (!(READ_ONCE(rnp->expmask) & rdp->grpmask) || __this_cpu_read(rcu_sched_data.cpu_no_qs.b.exp)) return; + if (rcu_is_cpu_rrupt_from_idle()) { + rcu_report_exp_rdp(&rcu_sched_state, + this_cpu_ptr(&rcu_sched_data), true); + return; + } __this_cpu_write(rcu_sched_data.cpu_no_qs.b.exp, true); resched_cpu(smp_processor_id()); } @@ -3773,7 +3867,7 @@ static void synchronize_sched_expedited_wait(struct rcu_state *rsp) rsp->name); ndetected = 0; rcu_for_each_leaf_node(rsp, rnp) { - ndetected = rcu_print_task_exp_stall(rnp); + ndetected += rcu_print_task_exp_stall(rnp); mask = 1; for (cpu = rnp->grplo; cpu <= rnp->grphi; cpu++, mask <<= 1) { struct rcu_data *rdp; @@ -3783,7 +3877,7 @@ static void synchronize_sched_expedited_wait(struct rcu_state *rsp) ndetected++; rdp = per_cpu_ptr(rsp->rda, cpu); pr_cont(" %d-%c%c%c", cpu, - "O."[cpu_online(cpu)], + "O."[!!cpu_online(cpu)], "o."[!!(rdp->grpmask & rnp->expmaskinit)], "N."[!!(rdp->grpmask & rnp->expmaskinitnext)]); } @@ -3792,7 +3886,7 @@ static void synchronize_sched_expedited_wait(struct rcu_state *rsp) pr_cont(" } %lu jiffies s: %lu root: %#lx/%c\n", jiffies - jiffies_start, rsp->expedited_sequence, rnp_root->expmask, ".T"[!!rnp_root->exp_tasks]); - if (!ndetected) { + if (ndetected) { pr_err("blocking rcu_node structures:"); rcu_for_each_node_breadth_first(rsp, rnp) { if (rnp == rnp_root) @@ -3818,6 +3912,41 @@ static void synchronize_sched_expedited_wait(struct rcu_state *rsp) } } +/* + * Wait for the current expedited grace period to complete, and then + * wake up everyone who piggybacked on the just-completed expedited + * grace period. Also update all the ->exp_seq_rq counters as needed + * in order to avoid counter-wrap problems. + */ +static void rcu_exp_wait_wake(struct rcu_state *rsp, unsigned long s) +{ + struct rcu_node *rnp; + + synchronize_sched_expedited_wait(rsp); + rcu_exp_gp_seq_end(rsp); + trace_rcu_exp_grace_period(rsp->name, s, TPS("end")); + + /* + * Switch over to wakeup mode, allowing the next GP, but -only- the + * next GP, to proceed. + */ + mutex_lock(&rsp->exp_wake_mutex); + mutex_unlock(&rsp->exp_mutex); + + rcu_for_each_node_breadth_first(rsp, rnp) { + if (ULONG_CMP_LT(READ_ONCE(rnp->exp_seq_rq), s)) { + spin_lock(&rnp->exp_lock); + /* Recheck, avoid hang in case someone just arrived. */ + if (ULONG_CMP_LT(rnp->exp_seq_rq, s)) + rnp->exp_seq_rq = s; + spin_unlock(&rnp->exp_lock); + } + wake_up_all(&rnp->exp_wq[(rsp->expedited_sequence >> 1) & 0x3]); + } + trace_rcu_exp_grace_period(rsp->name, s, TPS("endwake")); + mutex_unlock(&rsp->exp_wake_mutex); +} + /** * synchronize_sched_expedited - Brute-force RCU-sched grace period * @@ -3837,7 +3966,6 @@ static void synchronize_sched_expedited_wait(struct rcu_state *rsp) void synchronize_sched_expedited(void) { unsigned long s; - struct rcu_node *rnp; struct rcu_state *rsp = &rcu_sched_state; /* If only one CPU, this is automatically a grace period. */ @@ -3852,17 +3980,14 @@ void synchronize_sched_expedited(void) /* Take a snapshot of the sequence number. */ s = rcu_exp_gp_seq_snap(rsp); - - rnp = exp_funnel_lock(rsp, s); - if (rnp == NULL) + if (exp_funnel_lock(rsp, s)) return; /* Someone else did our work for us. */ - rcu_exp_gp_seq_start(rsp); + /* Initialize the rcu_node tree in preparation for the wait. */ sync_rcu_exp_select_cpus(rsp, sync_sched_exp_handler); - synchronize_sched_expedited_wait(rsp); - rcu_exp_gp_seq_end(rsp); - mutex_unlock(&rnp->exp_funnel_mutex); + /* Wait and clean up, including waking everyone. */ + rcu_exp_wait_wake(rsp, s); } EXPORT_SYMBOL_GPL(synchronize_sched_expedited); @@ -4162,7 +4287,6 @@ rcu_boot_init_percpu_data(int cpu, struct rcu_state *rsp) WARN_ON_ONCE(atomic_read(&rdp->dynticks->dynticks) != 1); rdp->cpu = cpu; rdp->rsp = rsp; - mutex_init(&rdp->exp_funnel_mutex); rcu_boot_init_nocb_percpu_data(rdp); raw_spin_unlock_irqrestore_rcu_node(rnp, flags); } @@ -4420,10 +4544,8 @@ static void __init rcu_init_one(struct rcu_state *rsp) { static const char * const buf[] = RCU_NODE_NAME_INIT; static const char * const fqs[] = RCU_FQS_NAME_INIT; - static const char * const exp[] = RCU_EXP_NAME_INIT; static struct lock_class_key rcu_node_class[RCU_NUM_LVLS]; static struct lock_class_key rcu_fqs_class[RCU_NUM_LVLS]; - static struct lock_class_key rcu_exp_class[RCU_NUM_LVLS]; static u8 fl_mask = 0x1; int levelcnt[RCU_NUM_LVLS]; /* # nodes in each level. */ @@ -4482,9 +4604,11 @@ static void __init rcu_init_one(struct rcu_state *rsp) rnp->level = i; INIT_LIST_HEAD(&rnp->blkd_tasks); rcu_init_one_nocb(rnp); - mutex_init(&rnp->exp_funnel_mutex); - lockdep_set_class_and_name(&rnp->exp_funnel_mutex, - &rcu_exp_class[i], exp[i]); + init_waitqueue_head(&rnp->exp_wq[0]); + init_waitqueue_head(&rnp->exp_wq[1]); + init_waitqueue_head(&rnp->exp_wq[2]); + init_waitqueue_head(&rnp->exp_wq[3]); + spin_lock_init(&rnp->exp_lock); } } diff --git a/kernel/rcu/tree.h b/kernel/rcu/tree.h index df668c0f9e64..e3959f5e6ddf 100644 --- a/kernel/rcu/tree.h +++ b/kernel/rcu/tree.h @@ -70,7 +70,6 @@ # define NUM_RCU_LVL_INIT { NUM_RCU_LVL_0 } # define RCU_NODE_NAME_INIT { "rcu_node_0" } # define RCU_FQS_NAME_INIT { "rcu_node_fqs_0" } -# define RCU_EXP_NAME_INIT { "rcu_node_exp_0" } #elif NR_CPUS <= RCU_FANOUT_2 # define RCU_NUM_LVLS 2 # define NUM_RCU_LVL_0 1 @@ -79,7 +78,6 @@ # define NUM_RCU_LVL_INIT { NUM_RCU_LVL_0, NUM_RCU_LVL_1 } # define RCU_NODE_NAME_INIT { "rcu_node_0", "rcu_node_1" } # define RCU_FQS_NAME_INIT { "rcu_node_fqs_0", "rcu_node_fqs_1" } -# define RCU_EXP_NAME_INIT { "rcu_node_exp_0", "rcu_node_exp_1" } #elif NR_CPUS <= RCU_FANOUT_3 # define RCU_NUM_LVLS 3 # define NUM_RCU_LVL_0 1 @@ -89,7 +87,6 @@ # define NUM_RCU_LVL_INIT { NUM_RCU_LVL_0, NUM_RCU_LVL_1, NUM_RCU_LVL_2 } # define RCU_NODE_NAME_INIT { "rcu_node_0", "rcu_node_1", "rcu_node_2" } # define RCU_FQS_NAME_INIT { "rcu_node_fqs_0", "rcu_node_fqs_1", "rcu_node_fqs_2" } -# define RCU_EXP_NAME_INIT { "rcu_node_exp_0", "rcu_node_exp_1", "rcu_node_exp_2" } #elif NR_CPUS <= RCU_FANOUT_4 # define RCU_NUM_LVLS 4 # define NUM_RCU_LVL_0 1 @@ -100,7 +97,6 @@ # define NUM_RCU_LVL_INIT { NUM_RCU_LVL_0, NUM_RCU_LVL_1, NUM_RCU_LVL_2, NUM_RCU_LVL_3 } # define RCU_NODE_NAME_INIT { "rcu_node_0", "rcu_node_1", "rcu_node_2", "rcu_node_3" } # define RCU_FQS_NAME_INIT { "rcu_node_fqs_0", "rcu_node_fqs_1", "rcu_node_fqs_2", "rcu_node_fqs_3" } -# define RCU_EXP_NAME_INIT { "rcu_node_exp_0", "rcu_node_exp_1", "rcu_node_exp_2", "rcu_node_exp_3" } #else # error "CONFIG_RCU_FANOUT insufficient for NR_CPUS" #endif /* #if (NR_CPUS) <= RCU_FANOUT_1 */ @@ -252,7 +248,9 @@ struct rcu_node { /* Counts of upcoming no-CB GP requests. */ raw_spinlock_t fqslock ____cacheline_internodealigned_in_smp; - struct mutex exp_funnel_mutex ____cacheline_internodealigned_in_smp; + spinlock_t exp_lock ____cacheline_internodealigned_in_smp; + unsigned long exp_seq_rq; + wait_queue_head_t exp_wq[4]; } ____cacheline_internodealigned_in_smp; /* @@ -387,11 +385,9 @@ struct rcu_data { #ifdef CONFIG_RCU_FAST_NO_HZ struct rcu_head oom_head; #endif /* #ifdef CONFIG_RCU_FAST_NO_HZ */ - struct mutex exp_funnel_mutex; - atomic_long_t expedited_workdone0; /* # done by others #0. */ - atomic_long_t expedited_workdone1; /* # done by others #1. */ - atomic_long_t expedited_workdone2; /* # done by others #2. */ - atomic_long_t expedited_workdone3; /* # done by others #3. */ + atomic_long_t exp_workdone1; /* # done by others #1. */ + atomic_long_t exp_workdone2; /* # done by others #2. */ + atomic_long_t exp_workdone3; /* # done by others #3. */ /* 7) Callback offloading. */ #ifdef CONFIG_RCU_NOCB_CPU @@ -505,6 +501,8 @@ struct rcu_state { /* _rcu_barrier(). */ /* End of fields guarded by barrier_mutex. */ + struct mutex exp_mutex; /* Serialize expedited GP. */ + struct mutex exp_wake_mutex; /* Serialize wakeup. */ unsigned long expedited_sequence; /* Take a ticket. */ atomic_long_t expedited_normal; /* # fallbacks to normal. */ atomic_t expedited_need_qs; /* # CPUs left to check in. */ @@ -513,6 +511,8 @@ struct rcu_state { unsigned long jiffies_force_qs; /* Time at which to invoke */ /* force_quiescent_state(). */ + unsigned long jiffies_kick_kthreads; /* Time at which to kick */ + /* kthreads, if configured. */ unsigned long n_force_qs; /* Number of calls to */ /* force_quiescent_state(). */ unsigned long n_force_qs_lh; /* ~Number of calls leaving */ diff --git a/kernel/rcu/tree_plugin.h b/kernel/rcu/tree_plugin.h index efdf7b61ce12..ff1cd4e1188d 100644 --- a/kernel/rcu/tree_plugin.h +++ b/kernel/rcu/tree_plugin.h @@ -722,18 +722,22 @@ static void sync_rcu_exp_handler(void *info) * synchronize_rcu_expedited - Brute-force RCU grace period * * Wait for an RCU-preempt grace period, but expedite it. The basic - * idea is to invoke synchronize_sched_expedited() to push all the tasks to - * the ->blkd_tasks lists and wait for this list to drain. This consumes - * significant time on all CPUs and is unfriendly to real-time workloads, - * so is thus not recommended for any sort of common-case code. - * In fact, if you are using synchronize_rcu_expedited() in a loop, - * please restructure your code to batch your updates, and then Use a - * single synchronize_rcu() instead. + * idea is to IPI all non-idle non-nohz online CPUs. The IPI handler + * checks whether the CPU is in an RCU-preempt critical section, and + * if so, it sets a flag that causes the outermost rcu_read_unlock() + * to report the quiescent state. On the other hand, if the CPU is + * not in an RCU read-side critical section, the IPI handler reports + * the quiescent state immediately. + * + * Although this is a greate improvement over previous expedited + * implementations, it is still unfriendly to real-time workloads, so is + * thus not recommended for any sort of common-case code. In fact, if + * you are using synchronize_rcu_expedited() in a loop, please restructure + * your code to batch your updates, and then Use a single synchronize_rcu() + * instead. */ void synchronize_rcu_expedited(void) { - struct rcu_node *rnp; - struct rcu_node *rnp_unlock; struct rcu_state *rsp = rcu_state_p; unsigned long s; @@ -744,23 +748,14 @@ void synchronize_rcu_expedited(void) } s = rcu_exp_gp_seq_snap(rsp); - - rnp_unlock = exp_funnel_lock(rsp, s); - if (rnp_unlock == NULL) + if (exp_funnel_lock(rsp, s)) return; /* Someone else did our work for us. */ - rcu_exp_gp_seq_start(rsp); - /* Initialize the rcu_node tree in preparation for the wait. */ sync_rcu_exp_select_cpus(rsp, sync_rcu_exp_handler); - /* Wait for snapshotted ->blkd_tasks lists to drain. */ - rnp = rcu_get_root(rsp); - synchronize_sched_expedited_wait(rsp); - - /* Clean up and exit. */ - rcu_exp_gp_seq_end(rsp); - mutex_unlock(&rnp_unlock->exp_funnel_mutex); + /* Wait for ->blkd_tasks lists to drain, then wake everyone up. */ + rcu_exp_wait_wake(rsp, s); } EXPORT_SYMBOL_GPL(synchronize_rcu_expedited); diff --git a/kernel/rcu/tree_trace.c b/kernel/rcu/tree_trace.c index 1088e64f01ad..86782f9a4604 100644 --- a/kernel/rcu/tree_trace.c +++ b/kernel/rcu/tree_trace.c @@ -185,17 +185,16 @@ static int show_rcuexp(struct seq_file *m, void *v) int cpu; struct rcu_state *rsp = (struct rcu_state *)m->private; struct rcu_data *rdp; - unsigned long s0 = 0, s1 = 0, s2 = 0, s3 = 0; + unsigned long s1 = 0, s2 = 0, s3 = 0; for_each_possible_cpu(cpu) { rdp = per_cpu_ptr(rsp->rda, cpu); - s0 += atomic_long_read(&rdp->expedited_workdone0); - s1 += atomic_long_read(&rdp->expedited_workdone1); - s2 += atomic_long_read(&rdp->expedited_workdone2); - s3 += atomic_long_read(&rdp->expedited_workdone3); + s1 += atomic_long_read(&rdp->exp_workdone1); + s2 += atomic_long_read(&rdp->exp_workdone2); + s3 += atomic_long_read(&rdp->exp_workdone3); } - seq_printf(m, "s=%lu wd0=%lu wd1=%lu wd2=%lu wd3=%lu n=%lu enq=%d sc=%lu\n", - rsp->expedited_sequence, s0, s1, s2, s3, + seq_printf(m, "s=%lu wd1=%lu wd2=%lu wd3=%lu n=%lu enq=%d sc=%lu\n", + rsp->expedited_sequence, s1, s2, s3, atomic_long_read(&rsp->expedited_normal), atomic_read(&rsp->expedited_need_qs), rsp->expedited_sequence / 2); diff --git a/kernel/rcu/update.c b/kernel/rcu/update.c index ca828b41c938..3ccdc8eebc5a 100644 --- a/kernel/rcu/update.c +++ b/kernel/rcu/update.c @@ -67,7 +67,7 @@ static int rcu_normal_after_boot; module_param(rcu_normal_after_boot, int, 0); #endif /* #ifndef CONFIG_TINY_RCU */ -#if defined(CONFIG_DEBUG_LOCK_ALLOC) && defined(CONFIG_PREEMPT_COUNT) +#ifdef CONFIG_DEBUG_LOCK_ALLOC /** * rcu_read_lock_sched_held() - might we be in RCU-sched read-side critical section? * @@ -111,7 +111,7 @@ int rcu_read_lock_sched_held(void) return 0; if (debug_locks) lockdep_opinion = lock_is_held(&rcu_sched_lock_map); - return lockdep_opinion || preempt_count() != 0 || irqs_disabled(); + return lockdep_opinion || !preemptible(); } EXPORT_SYMBOL(rcu_read_lock_sched_held); #endif diff --git a/kernel/resource.c b/kernel/resource.c index 2e78ead30934..9b5f04404152 100644 --- a/kernel/resource.c +++ b/kernel/resource.c @@ -105,16 +105,25 @@ static int r_show(struct seq_file *m, void *v) { struct resource *root = m->private; struct resource *r = v, *p; + unsigned long long start, end; int width = root->end < 0x10000 ? 4 : 8; int depth; for (depth = 0, p = r; depth < MAX_IORES_LEVEL; depth++, p = p->parent) if (p->parent == root) break; + + if (file_ns_capable(m->file, &init_user_ns, CAP_SYS_ADMIN)) { + start = r->start; + end = r->end; + } else { + start = end = 0; + } + seq_printf(m, "%*s%0*llx-%0*llx : %s\n", depth * 2, "", - width, (unsigned long long) r->start, - width, (unsigned long long) r->end, + width, start, + width, end, r->name ? r->name : "<BAD>"); return 0; } diff --git a/kernel/sched/Makefile b/kernel/sched/Makefile index 414d9c16da42..5e59b832ae2b 100644 --- a/kernel/sched/Makefile +++ b/kernel/sched/Makefile @@ -24,3 +24,4 @@ obj-$(CONFIG_SCHEDSTATS) += stats.o obj-$(CONFIG_SCHED_DEBUG) += debug.o obj-$(CONFIG_CGROUP_CPUACCT) += cpuacct.o obj-$(CONFIG_CPU_FREQ) += cpufreq.o +obj-$(CONFIG_CPU_FREQ_GOV_SCHEDUTIL) += cpufreq_schedutil.o diff --git a/kernel/sched/clock.c b/kernel/sched/clock.c index fedb967a9841..e85a725e5c34 100644 --- a/kernel/sched/clock.c +++ b/kernel/sched/clock.c @@ -318,6 +318,7 @@ u64 sched_clock_cpu(int cpu) return clock; } +EXPORT_SYMBOL_GPL(sched_clock_cpu); void sched_clock_tick(void) { @@ -363,39 +364,6 @@ void sched_clock_idle_wakeup_event(u64 delta_ns) } EXPORT_SYMBOL_GPL(sched_clock_idle_wakeup_event); -/* - * As outlined at the top, provides a fast, high resolution, nanosecond - * time source that is monotonic per cpu argument and has bounded drift - * between cpus. - * - * ######################### BIG FAT WARNING ########################## - * # when comparing cpu_clock(i) to cpu_clock(j) for i != j, time can # - * # go backwards !! # - * #################################################################### - */ -u64 cpu_clock(int cpu) -{ - if (!sched_clock_stable()) - return sched_clock_cpu(cpu); - - return sched_clock(); -} - -/* - * Similar to cpu_clock() for the current cpu. Time will only be observed - * to be monotonic if care is taken to only compare timestampt taken on the - * same CPU. - * - * See cpu_clock(). - */ -u64 local_clock(void) -{ - if (!sched_clock_stable()) - return sched_clock_cpu(raw_smp_processor_id()); - - return sched_clock(); -} - #else /* CONFIG_HAVE_UNSTABLE_SCHED_CLOCK */ void sched_clock_init(void) @@ -410,22 +378,8 @@ u64 sched_clock_cpu(int cpu) return sched_clock(); } - -u64 cpu_clock(int cpu) -{ - return sched_clock(); -} - -u64 local_clock(void) -{ - return sched_clock(); -} - #endif /* CONFIG_HAVE_UNSTABLE_SCHED_CLOCK */ -EXPORT_SYMBOL_GPL(cpu_clock); -EXPORT_SYMBOL_GPL(local_clock); - /* * Running clock - returns the time that has elapsed while a guest has been * running. diff --git a/kernel/sched/core.c b/kernel/sched/core.c index 8b489fcac37b..404c0784b1fc 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -33,7 +33,7 @@ #include <linux/init.h> #include <linux/uaccess.h> #include <linux/highmem.h> -#include <asm/mmu_context.h> +#include <linux/mmu_context.h> #include <linux/interrupt.h> #include <linux/capability.h> #include <linux/completion.h> @@ -170,6 +170,71 @@ static struct rq *this_rq_lock(void) return rq; } +/* + * __task_rq_lock - lock the rq @p resides on. + */ +struct rq *__task_rq_lock(struct task_struct *p, struct rq_flags *rf) + __acquires(rq->lock) +{ + struct rq *rq; + + lockdep_assert_held(&p->pi_lock); + + for (;;) { + rq = task_rq(p); + raw_spin_lock(&rq->lock); + if (likely(rq == task_rq(p) && !task_on_rq_migrating(p))) { + rf->cookie = lockdep_pin_lock(&rq->lock); + return rq; + } + raw_spin_unlock(&rq->lock); + + while (unlikely(task_on_rq_migrating(p))) + cpu_relax(); + } +} + +/* + * task_rq_lock - lock p->pi_lock and lock the rq @p resides on. + */ +struct rq *task_rq_lock(struct task_struct *p, struct rq_flags *rf) + __acquires(p->pi_lock) + __acquires(rq->lock) +{ + struct rq *rq; + + for (;;) { + raw_spin_lock_irqsave(&p->pi_lock, rf->flags); + rq = task_rq(p); + raw_spin_lock(&rq->lock); + /* + * move_queued_task() task_rq_lock() + * + * ACQUIRE (rq->lock) + * [S] ->on_rq = MIGRATING [L] rq = task_rq() + * WMB (__set_task_cpu()) ACQUIRE (rq->lock); + * [S] ->cpu = new_cpu [L] task_rq() + * [L] ->on_rq + * RELEASE (rq->lock) + * + * If we observe the old cpu in task_rq_lock, the acquire of + * the old rq->lock will fully serialize against the stores. + * + * If we observe the new cpu in task_rq_lock, the acquire will + * pair with the WMB to ensure we must then also see migrating. + */ + if (likely(rq == task_rq(p) && !task_on_rq_migrating(p))) { + rf->cookie = lockdep_pin_lock(&rq->lock); + return rq; + } + raw_spin_unlock(&rq->lock); + raw_spin_unlock_irqrestore(&p->pi_lock, rf->flags); + + while (unlikely(task_on_rq_migrating(p))) + cpu_relax(); + } +} + #ifdef CONFIG_SCHED_HRTICK /* * Use HR-timers to deliver accurate preemption points. @@ -249,29 +314,6 @@ void hrtick_start(struct rq *rq, u64 delay) } } -static int -hotplug_hrtick(struct notifier_block *nfb, unsigned long action, void *hcpu) -{ - int cpu = (int)(long)hcpu; - - switch (action) { - case CPU_UP_CANCELED: - case CPU_UP_CANCELED_FROZEN: - case CPU_DOWN_PREPARE: - case CPU_DOWN_PREPARE_FROZEN: - case CPU_DEAD: - case CPU_DEAD_FROZEN: - hrtick_clear(cpu_rq(cpu)); - return NOTIFY_OK; - } - - return NOTIFY_DONE; -} - -static __init void init_hrtick(void) -{ - hotcpu_notifier(hotplug_hrtick, 0); -} #else /* * Called to set the hrtick timer state. @@ -288,10 +330,6 @@ void hrtick_start(struct rq *rq, u64 delay) hrtimer_start(&rq->hrtick_timer, ns_to_ktime(delay), HRTIMER_MODE_REL_PINNED); } - -static inline void init_hrtick(void) -{ -} #endif /* CONFIG_SMP */ static void init_rq_hrtick(struct rq *rq) @@ -315,10 +353,6 @@ static inline void hrtick_clear(struct rq *rq) static inline void init_rq_hrtick(struct rq *rq) { } - -static inline void init_hrtick(void) -{ -} #endif /* CONFIG_SCHED_HRTICK */ /* @@ -400,7 +434,7 @@ void wake_q_add(struct wake_q_head *head, struct task_struct *task) * wakeup due to that. * * This cmpxchg() implies a full barrier, which pairs with the write - * barrier implied by the wakeup in wake_up_list(). + * barrier implied by the wakeup in wake_up_q(). */ if (cmpxchg(&node->next, NULL, WAKE_Q_TAIL)) return; @@ -499,7 +533,10 @@ int get_nohz_timer_target(void) rcu_read_lock(); for_each_domain(cpu, sd) { for_each_cpu(i, sched_domain_span(sd)) { - if (!idle_cpu(i) && is_housekeeping_cpu(cpu)) { + if (cpu == i) + continue; + + if (!idle_cpu(i) && is_housekeeping_cpu(i)) { cpu = i; goto unlock; } @@ -596,17 +633,8 @@ bool sched_can_stop_tick(struct rq *rq) return false; /* - * FIFO realtime policy runs the highest priority task (after DEADLINE). - * Other runnable tasks are of a lower priority. The scheduler tick - * isn't needed. - */ - fifo_nr_running = rq->rt.rt_nr_running - rq->rt.rr_nr_running; - if (fifo_nr_running) - return true; - - /* - * Round-robin realtime tasks time slice with other tasks at the same - * realtime priority. + * If there are more than one RR tasks, we need the tick to effect the + * actual RR behaviour. */ if (rq->rt.rr_nr_running) { if (rq->rt.rr_nr_running == 1) @@ -615,8 +643,20 @@ bool sched_can_stop_tick(struct rq *rq) return false; } - /* Normal multitasking need periodic preemption checks */ - if (rq->cfs.nr_running > 1) + /* + * If there's no RR tasks, but FIFO tasks, we can skip the tick, no + * forced preemption between FIFO tasks. + */ + fifo_nr_running = rq->rt.rt_nr_running - rq->rt.rr_nr_running; + if (fifo_nr_running) + return true; + + /* + * If there are no DL,RR/FIFO tasks, there must only be CFS tasks left; + * if there's more than one we need the tick for involuntary + * preemption. + */ + if (rq->nr_running > 1) return false; return true; @@ -1082,12 +1122,20 @@ void do_set_cpus_allowed(struct task_struct *p, const struct cpumask *new_mask) static int __set_cpus_allowed_ptr(struct task_struct *p, const struct cpumask *new_mask, bool check) { - unsigned long flags; - struct rq *rq; + const struct cpumask *cpu_valid_mask = cpu_active_mask; unsigned int dest_cpu; + struct rq_flags rf; + struct rq *rq; int ret = 0; - rq = task_rq_lock(p, &flags); + rq = task_rq_lock(p, &rf); + + if (p->flags & PF_KTHREAD) { + /* + * Kernel threads are allowed on online && !active CPUs + */ + cpu_valid_mask = cpu_online_mask; + } /* * Must re-check here, to close a race against __kthread_bind(), @@ -1101,22 +1149,32 @@ static int __set_cpus_allowed_ptr(struct task_struct *p, if (cpumask_equal(&p->cpus_allowed, new_mask)) goto out; - if (!cpumask_intersects(new_mask, cpu_active_mask)) { + if (!cpumask_intersects(new_mask, cpu_valid_mask)) { ret = -EINVAL; goto out; } do_set_cpus_allowed(p, new_mask); + if (p->flags & PF_KTHREAD) { + /* + * For kernel threads that do indeed end up on online && + * !active we want to ensure they are strict per-cpu threads. + */ + WARN_ON(cpumask_intersects(new_mask, cpu_online_mask) && + !cpumask_intersects(new_mask, cpu_active_mask) && + p->nr_cpus_allowed != 1); + } + /* Can the task run on the task's current CPU? If so, we're done */ if (cpumask_test_cpu(task_cpu(p), new_mask)) goto out; - dest_cpu = cpumask_any_and(cpu_active_mask, new_mask); + dest_cpu = cpumask_any_and(cpu_valid_mask, new_mask); if (task_running(rq, p) || p->state == TASK_WAKING) { struct migration_arg arg = { p, dest_cpu }; /* Need help from migration thread: drop lock and wait. */ - task_rq_unlock(rq, p, &flags); + task_rq_unlock(rq, p, &rf); stop_one_cpu(cpu_of(rq), migration_cpu_stop, &arg); tlb_migrate_finish(p->mm); return 0; @@ -1125,12 +1183,12 @@ static int __set_cpus_allowed_ptr(struct task_struct *p, * OK, since we're going to drop the lock immediately * afterwards anyway. */ - lockdep_unpin_lock(&rq->lock); + lockdep_unpin_lock(&rq->lock, rf.cookie); rq = move_queued_task(rq, p, dest_cpu); - lockdep_pin_lock(&rq->lock); + lockdep_repin_lock(&rq->lock, rf.cookie); } out: - task_rq_unlock(rq, p, &flags); + task_rq_unlock(rq, p, &rf); return ret; } @@ -1314,8 +1372,8 @@ out: */ unsigned long wait_task_inactive(struct task_struct *p, long match_state) { - unsigned long flags; int running, queued; + struct rq_flags rf; unsigned long ncsw; struct rq *rq; @@ -1350,14 +1408,14 @@ unsigned long wait_task_inactive(struct task_struct *p, long match_state) * lock now, to be *sure*. If we're wrong, we'll * just go back and repeat. */ - rq = task_rq_lock(p, &flags); + rq = task_rq_lock(p, &rf); trace_sched_wait_task(p); running = task_running(rq, p); queued = task_on_rq_queued(p); ncsw = 0; if (!match_state || p->state == match_state) ncsw = p->nvcsw | LONG_MIN; /* sets MSB */ - task_rq_unlock(rq, p, &flags); + task_rq_unlock(rq, p, &rf); /* * If it changed from the expected state, bail out now. @@ -1431,6 +1489,25 @@ EXPORT_SYMBOL_GPL(kick_process); /* * ->cpus_allowed is protected by both rq->lock and p->pi_lock + * + * A few notes on cpu_active vs cpu_online: + * + * - cpu_active must be a subset of cpu_online + * + * - on cpu-up we allow per-cpu kthreads on the online && !active cpu, + * see __set_cpus_allowed_ptr(). At this point the newly online + * cpu isn't yet part of the sched domains, and balancing will not + * see it. + * + * - on cpu-down we clear cpu_active() to mask the sched domains and + * avoid the load balancer to place new tasks on the to be removed + * cpu. Existing tasks will remain running there and will be taken + * off. + * + * This means that fallback selection must not select !active CPUs. + * And can assume that any active CPU must be online. Conversely + * select_task_rq() below may allow selection of !active CPUs in order + * to satisfy the above rules. */ static int select_fallback_rq(int cpu, struct task_struct *p) { @@ -1449,8 +1526,6 @@ static int select_fallback_rq(int cpu, struct task_struct *p) /* Look for allowed, online CPU in same node. */ for_each_cpu(dest_cpu, nodemask) { - if (!cpu_online(dest_cpu)) - continue; if (!cpu_active(dest_cpu)) continue; if (cpumask_test_cpu(dest_cpu, tsk_cpus_allowed(p))) @@ -1461,8 +1536,6 @@ static int select_fallback_rq(int cpu, struct task_struct *p) for (;;) { /* Any allowed, online CPU? */ for_each_cpu(dest_cpu, tsk_cpus_allowed(p)) { - if (!cpu_online(dest_cpu)) - continue; if (!cpu_active(dest_cpu)) continue; goto out; @@ -1512,8 +1585,10 @@ int select_task_rq(struct task_struct *p, int cpu, int sd_flags, int wake_flags) { lockdep_assert_held(&p->pi_lock); - if (p->nr_cpus_allowed > 1) + if (tsk_nr_cpus_allowed(p) > 1) cpu = p->sched_class->select_task_rq(p, cpu, sd_flags, wake_flags); + else + cpu = cpumask_any(tsk_cpus_allowed(p)); /* * In order not to call set_task_cpu() on a blocking task we need @@ -1601,8 +1676,8 @@ static inline void ttwu_activate(struct rq *rq, struct task_struct *p, int en_fl /* * Mark the task runnable and perform wakeup-preemption. */ -static void -ttwu_do_wakeup(struct rq *rq, struct task_struct *p, int wake_flags) +static void ttwu_do_wakeup(struct rq *rq, struct task_struct *p, int wake_flags, + struct pin_cookie cookie) { check_preempt_curr(rq, p, wake_flags); p->state = TASK_RUNNING; @@ -1614,9 +1689,9 @@ ttwu_do_wakeup(struct rq *rq, struct task_struct *p, int wake_flags) * Our task @p is fully woken up and running; so its safe to * drop the rq->lock, hereafter rq is only used for statistics. */ - lockdep_unpin_lock(&rq->lock); + lockdep_unpin_lock(&rq->lock, cookie); p->sched_class->task_woken(rq, p); - lockdep_pin_lock(&rq->lock); + lockdep_repin_lock(&rq->lock, cookie); } if (rq->idle_stamp) { @@ -1634,17 +1709,23 @@ ttwu_do_wakeup(struct rq *rq, struct task_struct *p, int wake_flags) } static void -ttwu_do_activate(struct rq *rq, struct task_struct *p, int wake_flags) +ttwu_do_activate(struct rq *rq, struct task_struct *p, int wake_flags, + struct pin_cookie cookie) { + int en_flags = ENQUEUE_WAKEUP; + lockdep_assert_held(&rq->lock); #ifdef CONFIG_SMP if (p->sched_contributes_to_load) rq->nr_uninterruptible--; + + if (wake_flags & WF_MIGRATED) + en_flags |= ENQUEUE_MIGRATED; #endif - ttwu_activate(rq, p, ENQUEUE_WAKEUP | ENQUEUE_WAKING); - ttwu_do_wakeup(rq, p, wake_flags); + ttwu_activate(rq, p, en_flags); + ttwu_do_wakeup(rq, p, wake_flags, cookie); } /* @@ -1655,17 +1736,18 @@ ttwu_do_activate(struct rq *rq, struct task_struct *p, int wake_flags) */ static int ttwu_remote(struct task_struct *p, int wake_flags) { + struct rq_flags rf; struct rq *rq; int ret = 0; - rq = __task_rq_lock(p); + rq = __task_rq_lock(p, &rf); if (task_on_rq_queued(p)) { /* check_preempt_curr() may use rq clock */ update_rq_clock(rq); - ttwu_do_wakeup(rq, p, wake_flags); + ttwu_do_wakeup(rq, p, wake_flags, rf.cookie); ret = 1; } - __task_rq_unlock(rq); + __task_rq_unlock(rq, &rf); return ret; } @@ -1675,6 +1757,7 @@ void sched_ttwu_pending(void) { struct rq *rq = this_rq(); struct llist_node *llist = llist_del_all(&rq->wake_list); + struct pin_cookie cookie; struct task_struct *p; unsigned long flags; @@ -1682,15 +1765,19 @@ void sched_ttwu_pending(void) return; raw_spin_lock_irqsave(&rq->lock, flags); - lockdep_pin_lock(&rq->lock); + cookie = lockdep_pin_lock(&rq->lock); while (llist) { p = llist_entry(llist, struct task_struct, wake_entry); llist = llist_next(llist); - ttwu_do_activate(rq, p, 0); + /* + * See ttwu_queue(); we only call ttwu_queue_remote() when + * its a x-cpu wakeup. + */ + ttwu_do_activate(rq, p, WF_MIGRATED, cookie); } - lockdep_unpin_lock(&rq->lock); + lockdep_unpin_lock(&rq->lock, cookie); raw_spin_unlock_irqrestore(&rq->lock, flags); } @@ -1774,9 +1861,10 @@ bool cpus_share_cache(int this_cpu, int that_cpu) } #endif /* CONFIG_SMP */ -static void ttwu_queue(struct task_struct *p, int cpu) +static void ttwu_queue(struct task_struct *p, int cpu, int wake_flags) { struct rq *rq = cpu_rq(cpu); + struct pin_cookie cookie; #if defined(CONFIG_SMP) if (sched_feat(TTWU_QUEUE) && !cpus_share_cache(smp_processor_id(), cpu)) { @@ -1787,9 +1875,9 @@ static void ttwu_queue(struct task_struct *p, int cpu) #endif raw_spin_lock(&rq->lock); - lockdep_pin_lock(&rq->lock); - ttwu_do_activate(rq, p, 0); - lockdep_unpin_lock(&rq->lock); + cookie = lockdep_pin_lock(&rq->lock); + ttwu_do_activate(rq, p, wake_flags, cookie); + lockdep_unpin_lock(&rq->lock, cookie); raw_spin_unlock(&rq->lock); } @@ -1958,9 +2046,6 @@ try_to_wake_up(struct task_struct *p, unsigned int state, int wake_flags) p->sched_contributes_to_load = !!task_contributes_to_load(p); p->state = TASK_WAKING; - if (p->sched_class->task_waking) - p->sched_class->task_waking(p); - cpu = select_task_rq(p, p->wake_cpu, SD_BALANCE_WAKE, wake_flags); if (task_cpu(p) != cpu) { wake_flags |= WF_MIGRATED; @@ -1968,7 +2053,7 @@ try_to_wake_up(struct task_struct *p, unsigned int state, int wake_flags) } #endif /* CONFIG_SMP */ - ttwu_queue(p, cpu); + ttwu_queue(p, cpu, wake_flags); stat: if (schedstat_enabled()) ttwu_stat(p, cpu, wake_flags); @@ -1986,7 +2071,7 @@ out: * ensure that this_rq() is locked, @p is bound to this_rq() and not * the current task. */ -static void try_to_wake_up_local(struct task_struct *p) +static void try_to_wake_up_local(struct task_struct *p, struct pin_cookie cookie) { struct rq *rq = task_rq(p); @@ -2003,11 +2088,11 @@ static void try_to_wake_up_local(struct task_struct *p) * disabled avoiding further scheduler activity on it and we've * not yet picked a replacement task. */ - lockdep_unpin_lock(&rq->lock); + lockdep_unpin_lock(&rq->lock, cookie); raw_spin_unlock(&rq->lock); raw_spin_lock(&p->pi_lock); raw_spin_lock(&rq->lock); - lockdep_pin_lock(&rq->lock); + lockdep_repin_lock(&rq->lock, cookie); } if (!(p->state & TASK_NORMAL)) @@ -2018,7 +2103,7 @@ static void try_to_wake_up_local(struct task_struct *p) if (!task_on_rq_queued(p)) ttwu_activate(rq, p, ENQUEUE_WAKEUP); - ttwu_do_wakeup(rq, p, 0); + ttwu_do_wakeup(rq, p, 0, cookie); if (schedstat_enabled()) ttwu_stat(p, smp_processor_id(), 0); out: @@ -2378,7 +2463,8 @@ static int dl_overflow(struct task_struct *p, int policy, u64 new_bw = dl_policy(policy) ? to_ratio(period, runtime) : 0; int cpus, err = -1; - if (new_bw == p->dl.dl_bw) + /* !deadline task may carry old deadline bandwidth */ + if (new_bw == p->dl.dl_bw && task_has_dl_policy(p)) return 0; /* @@ -2417,12 +2503,12 @@ extern void init_dl_bw(struct dl_bw *dl_b); */ void wake_up_new_task(struct task_struct *p) { - unsigned long flags; + struct rq_flags rf; struct rq *rq; - raw_spin_lock_irqsave(&p->pi_lock, flags); /* Initialize new task's runnable average */ init_entity_runnable_average(&p->se); + raw_spin_lock_irqsave(&p->pi_lock, rf.flags); #ifdef CONFIG_SMP /* * Fork balancing, do it here and not earlier because: @@ -2431,8 +2517,10 @@ void wake_up_new_task(struct task_struct *p) */ set_task_cpu(p, select_task_rq(p, task_cpu(p), SD_BALANCE_FORK, 0)); #endif + /* Post initialize new task's util average when its cfs_rq is set */ + post_init_entity_util_avg(&p->se); - rq = __task_rq_lock(p); + rq = __task_rq_lock(p, &rf); activate_task(rq, p, 0); p->on_rq = TASK_ON_RQ_QUEUED; trace_sched_wakeup_new(p); @@ -2443,12 +2531,12 @@ void wake_up_new_task(struct task_struct *p) * Nothing relies on rq->lock after this, so its fine to * drop it. */ - lockdep_unpin_lock(&rq->lock); + lockdep_unpin_lock(&rq->lock, rf.cookie); p->sched_class->task_woken(rq, p); - lockdep_pin_lock(&rq->lock); + lockdep_repin_lock(&rq->lock, rf.cookie); } #endif - task_rq_unlock(rq, p, &flags); + task_rq_unlock(rq, p, &rf); } #ifdef CONFIG_PREEMPT_NOTIFIERS @@ -2710,7 +2798,7 @@ asmlinkage __visible void schedule_tail(struct task_struct *prev) */ static __always_inline struct rq * context_switch(struct rq *rq, struct task_struct *prev, - struct task_struct *next) + struct task_struct *next, struct pin_cookie cookie) { struct mm_struct *mm, *oldmm; @@ -2730,7 +2818,7 @@ context_switch(struct rq *rq, struct task_struct *prev, atomic_inc(&oldmm->mm_count); enter_lazy_tlb(oldmm, next); } else - switch_mm(oldmm, mm, next); + switch_mm_irqs_off(oldmm, mm, next); if (!prev->mm) { prev->active_mm = NULL; @@ -2742,7 +2830,7 @@ context_switch(struct rq *rq, struct task_struct *prev, * of the scheduler it's an obvious special-case), so we * do an early lockdep release here: */ - lockdep_unpin_lock(&rq->lock); + lockdep_unpin_lock(&rq->lock, cookie); spin_release(&rq->lock.dep_map, 1, _THIS_IP_); /* Here we just switch the register state and the stack. */ @@ -2864,7 +2952,7 @@ EXPORT_PER_CPU_SYMBOL(kernel_cpustat); */ unsigned long long task_sched_runtime(struct task_struct *p) { - unsigned long flags; + struct rq_flags rf; struct rq *rq; u64 ns; @@ -2884,7 +2972,7 @@ unsigned long long task_sched_runtime(struct task_struct *p) return p->se.sum_exec_runtime; #endif - rq = task_rq_lock(p, &flags); + rq = task_rq_lock(p, &rf); /* * Must be ->curr _and_ ->on_rq. If dequeued, we would * project cycles that may never be accounted to this @@ -2895,7 +2983,7 @@ unsigned long long task_sched_runtime(struct task_struct *p) p->sched_class->update_curr(rq); } ns = p->se.sum_exec_runtime; - task_rq_unlock(rq, p, &flags); + task_rq_unlock(rq, p, &rf); return ns; } @@ -2915,7 +3003,7 @@ void scheduler_tick(void) raw_spin_lock(&rq->lock); update_rq_clock(rq); curr->sched_class->task_tick(rq, curr, 0); - update_cpu_load_active(rq); + cpu_load_update_active(rq); calc_global_load_tick(rq); raw_spin_unlock(&rq->lock); @@ -2958,6 +3046,20 @@ u64 scheduler_tick_max_deferment(void) #if defined(CONFIG_PREEMPT) && (defined(CONFIG_DEBUG_PREEMPT) || \ defined(CONFIG_PREEMPT_TRACER)) +/* + * If the value passed in is equal to the current preempt count + * then we just disabled preemption. Start timing the latency. + */ +static inline void preempt_latency_start(int val) +{ + if (preempt_count() == val) { + unsigned long ip = get_lock_parent_ip(); +#ifdef CONFIG_DEBUG_PREEMPT + current->preempt_disable_ip = ip; +#endif + trace_preempt_off(CALLER_ADDR0, ip); + } +} void preempt_count_add(int val) { @@ -2976,17 +3078,21 @@ void preempt_count_add(int val) DEBUG_LOCKS_WARN_ON((preempt_count() & PREEMPT_MASK) >= PREEMPT_MASK - 10); #endif - if (preempt_count() == val) { - unsigned long ip = get_lock_parent_ip(); -#ifdef CONFIG_DEBUG_PREEMPT - current->preempt_disable_ip = ip; -#endif - trace_preempt_off(CALLER_ADDR0, ip); - } + preempt_latency_start(val); } EXPORT_SYMBOL(preempt_count_add); NOKPROBE_SYMBOL(preempt_count_add); +/* + * If the value passed in equals to the current preempt count + * then we just enabled preemption. Stop timing the latency. + */ +static inline void preempt_latency_stop(int val) +{ + if (preempt_count() == val) + trace_preempt_on(CALLER_ADDR0, get_lock_parent_ip()); +} + void preempt_count_sub(int val) { #ifdef CONFIG_DEBUG_PREEMPT @@ -3003,13 +3109,15 @@ void preempt_count_sub(int val) return; #endif - if (preempt_count() == val) - trace_preempt_on(CALLER_ADDR0, get_lock_parent_ip()); + preempt_latency_stop(val); __preempt_count_sub(val); } EXPORT_SYMBOL(preempt_count_sub); NOKPROBE_SYMBOL(preempt_count_sub); +#else +static inline void preempt_latency_start(int val) { } +static inline void preempt_latency_stop(int val) { } #endif /* @@ -3062,7 +3170,7 @@ static inline void schedule_debug(struct task_struct *prev) * Pick up the highest-prio task: */ static inline struct task_struct * -pick_next_task(struct rq *rq, struct task_struct *prev) +pick_next_task(struct rq *rq, struct task_struct *prev, struct pin_cookie cookie) { const struct sched_class *class = &fair_sched_class; struct task_struct *p; @@ -3073,20 +3181,20 @@ pick_next_task(struct rq *rq, struct task_struct *prev) */ if (likely(prev->sched_class == class && rq->nr_running == rq->cfs.h_nr_running)) { - p = fair_sched_class.pick_next_task(rq, prev); + p = fair_sched_class.pick_next_task(rq, prev, cookie); if (unlikely(p == RETRY_TASK)) goto again; /* assumes fair_sched_class->next == idle_sched_class */ if (unlikely(!p)) - p = idle_sched_class.pick_next_task(rq, prev); + p = idle_sched_class.pick_next_task(rq, prev, cookie); return p; } again: for_each_class(class) { - p = class->pick_next_task(rq, prev); + p = class->pick_next_task(rq, prev, cookie); if (p) { if (unlikely(p == RETRY_TASK)) goto again; @@ -3140,6 +3248,7 @@ static void __sched notrace __schedule(bool preempt) { struct task_struct *prev, *next; unsigned long *switch_count; + struct pin_cookie cookie; struct rq *rq; int cpu; @@ -3173,7 +3282,7 @@ static void __sched notrace __schedule(bool preempt) */ smp_mb__before_spinlock(); raw_spin_lock(&rq->lock); - lockdep_pin_lock(&rq->lock); + cookie = lockdep_pin_lock(&rq->lock); rq->clock_skip_update <<= 1; /* promote REQ to ACT */ @@ -3195,7 +3304,7 @@ static void __sched notrace __schedule(bool preempt) to_wakeup = wq_worker_sleeping(prev); if (to_wakeup) - try_to_wake_up_local(to_wakeup); + try_to_wake_up_local(to_wakeup, cookie); } } switch_count = &prev->nvcsw; @@ -3204,7 +3313,7 @@ static void __sched notrace __schedule(bool preempt) if (task_on_rq_queued(prev)) update_rq_clock(rq); - next = pick_next_task(rq, prev); + next = pick_next_task(rq, prev, cookie); clear_tsk_need_resched(prev); clear_preempt_need_resched(); rq->clock_skip_update = 0; @@ -3215,9 +3324,9 @@ static void __sched notrace __schedule(bool preempt) ++*switch_count; trace_sched_switch(preempt, prev, next); - rq = context_switch(rq, prev, next); /* unlocks the rq */ + rq = context_switch(rq, prev, next, cookie); /* unlocks the rq */ } else { - lockdep_unpin_lock(&rq->lock); + lockdep_unpin_lock(&rq->lock, cookie); raw_spin_unlock_irq(&rq->lock); } @@ -3284,8 +3393,23 @@ void __sched schedule_preempt_disabled(void) static void __sched notrace preempt_schedule_common(void) { do { + /* + * Because the function tracer can trace preempt_count_sub() + * and it also uses preempt_enable/disable_notrace(), if + * NEED_RESCHED is set, the preempt_enable_notrace() called + * by the function tracer will call this function again and + * cause infinite recursion. + * + * Preemption must be disabled here before the function + * tracer can trace. Break up preempt_disable() into two + * calls. One to disable preemption without fear of being + * traced. The other to still record the preemption latency, + * which can also be traced by the function tracer. + */ preempt_disable_notrace(); + preempt_latency_start(1); __schedule(true); + preempt_latency_stop(1); preempt_enable_no_resched_notrace(); /* @@ -3337,7 +3461,21 @@ asmlinkage __visible void __sched notrace preempt_schedule_notrace(void) return; do { + /* + * Because the function tracer can trace preempt_count_sub() + * and it also uses preempt_enable/disable_notrace(), if + * NEED_RESCHED is set, the preempt_enable_notrace() called + * by the function tracer will call this function again and + * cause infinite recursion. + * + * Preemption must be disabled here before the function + * tracer can trace. Break up preempt_disable() into two + * calls. One to disable preemption without fear of being + * traced. The other to still record the preemption latency, + * which can also be traced by the function tracer. + */ preempt_disable_notrace(); + preempt_latency_start(1); /* * Needs preempt disabled in case user_exit() is traced * and the tracer calls preempt_enable_notrace() causing @@ -3347,6 +3485,7 @@ asmlinkage __visible void __sched notrace preempt_schedule_notrace(void) __schedule(true); exception_exit(prev_ctx); + preempt_latency_stop(1); preempt_enable_no_resched_notrace(); } while (need_resched()); } @@ -3403,12 +3542,13 @@ EXPORT_SYMBOL(default_wake_function); void rt_mutex_setprio(struct task_struct *p, int prio) { int oldprio, queued, running, queue_flag = DEQUEUE_SAVE | DEQUEUE_MOVE; - struct rq *rq; const struct sched_class *prev_class; + struct rq_flags rf; + struct rq *rq; BUG_ON(prio > MAX_PRIO); - rq = __task_rq_lock(p); + rq = __task_rq_lock(p, &rf); /* * Idle task boosting is a nono in general. There is one @@ -3484,7 +3624,7 @@ void rt_mutex_setprio(struct task_struct *p, int prio) check_class_changed(rq, p, prev_class, oldprio); out_unlock: preempt_disable(); /* avoid rq from going away on us */ - __task_rq_unlock(rq); + __task_rq_unlock(rq, &rf); balance_callback(rq); preempt_enable(); @@ -3494,7 +3634,7 @@ out_unlock: void set_user_nice(struct task_struct *p, long nice) { int old_prio, delta, queued; - unsigned long flags; + struct rq_flags rf; struct rq *rq; if (task_nice(p) == nice || nice < MIN_NICE || nice > MAX_NICE) @@ -3503,7 +3643,7 @@ void set_user_nice(struct task_struct *p, long nice) * We have to be careful, if called from sys_setpriority(), * the task might be in the middle of scheduling on another CPU. */ - rq = task_rq_lock(p, &flags); + rq = task_rq_lock(p, &rf); /* * The RT priorities are set via sched_setscheduler(), but we still * allow the 'normal' nice value to be set - but as expected @@ -3534,7 +3674,7 @@ void set_user_nice(struct task_struct *p, long nice) resched_curr(rq); } out_unlock: - task_rq_unlock(rq, p, &flags); + task_rq_unlock(rq, p, &rf); } EXPORT_SYMBOL(set_user_nice); @@ -3831,11 +3971,11 @@ static int __sched_setscheduler(struct task_struct *p, MAX_RT_PRIO - 1 - attr->sched_priority; int retval, oldprio, oldpolicy = -1, queued, running; int new_effective_prio, policy = attr->sched_policy; - unsigned long flags; const struct sched_class *prev_class; - struct rq *rq; + struct rq_flags rf; int reset_on_fork; int queue_flags = DEQUEUE_SAVE | DEQUEUE_MOVE; + struct rq *rq; /* may grab non-irq protected spin_locks */ BUG_ON(in_interrupt()); @@ -3930,13 +4070,13 @@ recheck: * To be able to change p->policy safely, the appropriate * runqueue lock must be held. */ - rq = task_rq_lock(p, &flags); + rq = task_rq_lock(p, &rf); /* * Changing the policy of the stop threads its a very bad idea */ if (p == rq->stop) { - task_rq_unlock(rq, p, &flags); + task_rq_unlock(rq, p, &rf); return -EINVAL; } @@ -3953,7 +4093,7 @@ recheck: goto change; p->sched_reset_on_fork = reset_on_fork; - task_rq_unlock(rq, p, &flags); + task_rq_unlock(rq, p, &rf); return 0; } change: @@ -3967,7 +4107,7 @@ change: if (rt_bandwidth_enabled() && rt_policy(policy) && task_group(p)->rt_bandwidth.rt_runtime == 0 && !task_group_is_autogroup(task_group(p))) { - task_rq_unlock(rq, p, &flags); + task_rq_unlock(rq, p, &rf); return -EPERM; } #endif @@ -3982,7 +4122,7 @@ change: */ if (!cpumask_subset(span, &p->cpus_allowed) || rq->rd->dl_bw.bw == 0) { - task_rq_unlock(rq, p, &flags); + task_rq_unlock(rq, p, &rf); return -EPERM; } } @@ -3992,7 +4132,7 @@ change: /* recheck policy now with rq lock held */ if (unlikely(oldpolicy != -1 && oldpolicy != p->policy)) { policy = oldpolicy = -1; - task_rq_unlock(rq, p, &flags); + task_rq_unlock(rq, p, &rf); goto recheck; } @@ -4002,7 +4142,7 @@ change: * is available. */ if ((dl_policy(policy) || dl_task(p)) && dl_overflow(p, policy, attr)) { - task_rq_unlock(rq, p, &flags); + task_rq_unlock(rq, p, &rf); return -EBUSY; } @@ -4047,7 +4187,7 @@ change: check_class_changed(rq, p, prev_class, oldprio); preempt_disable(); /* avoid rq from going away on us */ - task_rq_unlock(rq, p, &flags); + task_rq_unlock(rq, p, &rf); if (pi) rt_mutex_adjust_pi(p); @@ -4900,10 +5040,10 @@ SYSCALL_DEFINE2(sched_rr_get_interval, pid_t, pid, { struct task_struct *p; unsigned int time_slice; - unsigned long flags; + struct rq_flags rf; + struct timespec t; struct rq *rq; int retval; - struct timespec t; if (pid < 0) return -EINVAL; @@ -4918,11 +5058,11 @@ SYSCALL_DEFINE2(sched_rr_get_interval, pid_t, pid, if (retval) goto out_unlock; - rq = task_rq_lock(p, &flags); + rq = task_rq_lock(p, &rf); time_slice = 0; if (p->sched_class->get_rr_interval) time_slice = p->sched_class->get_rr_interval(rq, p); - task_rq_unlock(rq, p, &flags); + task_rq_unlock(rq, p, &rf); rcu_read_unlock(); jiffies_to_timespec(time_slice, &t); @@ -4998,7 +5138,8 @@ void show_state_filter(unsigned long state_filter) touch_all_softlockup_watchdogs(); #ifdef CONFIG_SCHED_DEBUG - sysrq_sched_debug_show(); + if (!state_filter) + sysrq_sched_debug_show(); #endif rcu_read_unlock(); /* @@ -5160,6 +5301,8 @@ out: #ifdef CONFIG_SMP +static bool sched_smp_initialized __read_mostly; + #ifdef CONFIG_NUMA_BALANCING /* Migrate current task p to target_cpu */ int migrate_task_to(struct task_struct *p, int target_cpu) @@ -5185,11 +5328,11 @@ int migrate_task_to(struct task_struct *p, int target_cpu) */ void sched_setnuma(struct task_struct *p, int nid) { - struct rq *rq; - unsigned long flags; bool queued, running; + struct rq_flags rf; + struct rq *rq; - rq = task_rq_lock(p, &flags); + rq = task_rq_lock(p, &rf); queued = task_on_rq_queued(p); running = task_current(rq, p); @@ -5204,7 +5347,7 @@ void sched_setnuma(struct task_struct *p, int nid) p->sched_class->set_curr_task(rq); if (queued) enqueue_task(rq, p, ENQUEUE_RESTORE); - task_rq_unlock(rq, p, &flags); + task_rq_unlock(rq, p, &rf); } #endif /* CONFIG_NUMA_BALANCING */ @@ -5220,7 +5363,7 @@ void idle_task_exit(void) BUG_ON(cpu_online(smp_processor_id())); if (mm != &init_mm) { - switch_mm(mm, &init_mm, current); + switch_mm_irqs_off(mm, &init_mm, current); finish_arch_post_lock_switch(); } mmdrop(mm); @@ -5268,6 +5411,7 @@ static void migrate_tasks(struct rq *dead_rq) { struct rq *rq = dead_rq; struct task_struct *next, *stop = rq->stop; + struct pin_cookie cookie; int dest_cpu; /* @@ -5299,8 +5443,8 @@ static void migrate_tasks(struct rq *dead_rq) /* * pick_next_task assumes pinned rq->lock. */ - lockdep_pin_lock(&rq->lock); - next = pick_next_task(rq, &fake_task); + cookie = lockdep_pin_lock(&rq->lock); + next = pick_next_task(rq, &fake_task, cookie); BUG_ON(!next); next->sched_class->put_prev_task(rq, next); @@ -5313,7 +5457,7 @@ static void migrate_tasks(struct rq *dead_rq) * because !cpu_active at this point, which means load-balance * will not interfere. Also, stop-machine. */ - lockdep_unpin_lock(&rq->lock); + lockdep_unpin_lock(&rq->lock, cookie); raw_spin_unlock(&rq->lock); raw_spin_lock(&next->pi_lock); raw_spin_lock(&rq->lock); @@ -5374,127 +5518,13 @@ static void set_rq_offline(struct rq *rq) } } -/* - * migration_call - callback that gets triggered when a CPU is added. - * Here we can start up the necessary migration thread for the new CPU. - */ -static int -migration_call(struct notifier_block *nfb, unsigned long action, void *hcpu) +static void set_cpu_rq_start_time(unsigned int cpu) { - int cpu = (long)hcpu; - unsigned long flags; struct rq *rq = cpu_rq(cpu); - switch (action & ~CPU_TASKS_FROZEN) { - - case CPU_UP_PREPARE: - rq->calc_load_update = calc_load_update; - account_reset_rq(rq); - break; - - case CPU_ONLINE: - /* Update our root-domain */ - raw_spin_lock_irqsave(&rq->lock, flags); - if (rq->rd) { - BUG_ON(!cpumask_test_cpu(cpu, rq->rd->span)); - - set_rq_online(rq); - } - raw_spin_unlock_irqrestore(&rq->lock, flags); - break; - -#ifdef CONFIG_HOTPLUG_CPU - case CPU_DYING: - sched_ttwu_pending(); - /* Update our root-domain */ - raw_spin_lock_irqsave(&rq->lock, flags); - if (rq->rd) { - BUG_ON(!cpumask_test_cpu(cpu, rq->rd->span)); - set_rq_offline(rq); - } - migrate_tasks(rq); - BUG_ON(rq->nr_running != 1); /* the migration thread */ - raw_spin_unlock_irqrestore(&rq->lock, flags); - break; - - case CPU_DEAD: - calc_load_migrate(rq); - break; -#endif - } - - update_max_interval(); - - return NOTIFY_OK; -} - -/* - * Register at high priority so that task migration (migrate_all_tasks) - * happens before everything else. This has to be lower priority than - * the notifier in the perf_event subsystem, though. - */ -static struct notifier_block migration_notifier = { - .notifier_call = migration_call, - .priority = CPU_PRI_MIGRATION, -}; - -static void set_cpu_rq_start_time(void) -{ - int cpu = smp_processor_id(); - struct rq *rq = cpu_rq(cpu); rq->age_stamp = sched_clock_cpu(cpu); } -static int sched_cpu_active(struct notifier_block *nfb, - unsigned long action, void *hcpu) -{ - int cpu = (long)hcpu; - - switch (action & ~CPU_TASKS_FROZEN) { - case CPU_STARTING: - set_cpu_rq_start_time(); - return NOTIFY_OK; - - case CPU_DOWN_FAILED: - set_cpu_active(cpu, true); - return NOTIFY_OK; - - default: - return NOTIFY_DONE; - } -} - -static int sched_cpu_inactive(struct notifier_block *nfb, - unsigned long action, void *hcpu) -{ - switch (action & ~CPU_TASKS_FROZEN) { - case CPU_DOWN_PREPARE: - set_cpu_active((long)hcpu, false); - return NOTIFY_OK; - default: - return NOTIFY_DONE; - } -} - -static int __init migration_init(void) -{ - void *cpu = (void *)(long)smp_processor_id(); - int err; - - /* Initialize migration for the boot CPU */ - err = migration_call(&migration_notifier, CPU_UP_PREPARE, cpu); - BUG_ON(err == NOTIFY_BAD); - migration_call(&migration_notifier, CPU_ONLINE, cpu); - register_cpu_notifier(&migration_notifier); - - /* Register cpu active notifiers */ - cpu_notifier(sched_cpu_active, CPU_PRI_SCHED_ACTIVE); - cpu_notifier(sched_cpu_inactive, CPU_PRI_SCHED_INACTIVE); - - return 0; -} -early_initcall(migration_init); - static cpumask_var_t sched_domains_tmpmask; /* sched_domains_mutex */ #ifdef CONFIG_SCHED_DEBUG @@ -6642,10 +6672,10 @@ static void sched_init_numa(void) init_numa_topology_type(); } -static void sched_domains_numa_masks_set(int cpu) +static void sched_domains_numa_masks_set(unsigned int cpu) { - int i, j; int node = cpu_to_node(cpu); + int i, j; for (i = 0; i < sched_domains_numa_levels; i++) { for (j = 0; j < nr_node_ids; j++) { @@ -6655,51 +6685,20 @@ static void sched_domains_numa_masks_set(int cpu) } } -static void sched_domains_numa_masks_clear(int cpu) +static void sched_domains_numa_masks_clear(unsigned int cpu) { int i, j; + for (i = 0; i < sched_domains_numa_levels; i++) { for (j = 0; j < nr_node_ids; j++) cpumask_clear_cpu(cpu, sched_domains_numa_masks[i][j]); } } -/* - * Update sched_domains_numa_masks[level][node] array when new cpus - * are onlined. - */ -static int sched_domains_numa_masks_update(struct notifier_block *nfb, - unsigned long action, - void *hcpu) -{ - int cpu = (long)hcpu; - - switch (action & ~CPU_TASKS_FROZEN) { - case CPU_ONLINE: - sched_domains_numa_masks_set(cpu); - break; - - case CPU_DEAD: - sched_domains_numa_masks_clear(cpu); - break; - - default: - return NOTIFY_DONE; - } - - return NOTIFY_OK; -} #else -static inline void sched_init_numa(void) -{ -} - -static int sched_domains_numa_masks_update(struct notifier_block *nfb, - unsigned long action, - void *hcpu) -{ - return 0; -} +static inline void sched_init_numa(void) { } +static void sched_domains_numa_masks_set(unsigned int cpu) { } +static void sched_domains_numa_masks_clear(unsigned int cpu) { } #endif /* CONFIG_NUMA */ static int __sdt_alloc(const struct cpumask *cpu_map) @@ -7089,13 +7088,9 @@ static int num_cpus_frozen; /* used to mark begin/end of suspend/resume */ * If we come here as part of a suspend/resume, don't touch cpusets because we * want to restore it back to its original state upon resume anyway. */ -static int cpuset_cpu_active(struct notifier_block *nfb, unsigned long action, - void *hcpu) +static void cpuset_cpu_active(void) { - switch (action) { - case CPU_ONLINE_FROZEN: - case CPU_DOWN_FAILED_FROZEN: - + if (cpuhp_tasks_frozen) { /* * num_cpus_frozen tracks how many CPUs are involved in suspend * resume sequence. As long as this is not the last online @@ -7105,35 +7100,25 @@ static int cpuset_cpu_active(struct notifier_block *nfb, unsigned long action, num_cpus_frozen--; if (likely(num_cpus_frozen)) { partition_sched_domains(1, NULL, NULL); - break; + return; } - /* * This is the last CPU online operation. So fall through and * restore the original sched domains by considering the * cpuset configurations. */ - - case CPU_ONLINE: - cpuset_update_active_cpus(true); - break; - default: - return NOTIFY_DONE; } - return NOTIFY_OK; + cpuset_update_active_cpus(true); } -static int cpuset_cpu_inactive(struct notifier_block *nfb, unsigned long action, - void *hcpu) +static int cpuset_cpu_inactive(unsigned int cpu) { unsigned long flags; - long cpu = (long)hcpu; struct dl_bw *dl_b; bool overflow; int cpus; - switch (action) { - case CPU_DOWN_PREPARE: + if (!cpuhp_tasks_frozen) { rcu_read_lock_sched(); dl_b = dl_bw_of(cpu); @@ -7145,18 +7130,119 @@ static int cpuset_cpu_inactive(struct notifier_block *nfb, unsigned long action, rcu_read_unlock_sched(); if (overflow) - return notifier_from_errno(-EBUSY); + return -EBUSY; cpuset_update_active_cpus(false); - break; - case CPU_DOWN_PREPARE_FROZEN: + } else { num_cpus_frozen++; partition_sched_domains(1, NULL, NULL); - break; - default: - return NOTIFY_DONE; } - return NOTIFY_OK; + return 0; +} + +int sched_cpu_activate(unsigned int cpu) +{ + struct rq *rq = cpu_rq(cpu); + unsigned long flags; + + set_cpu_active(cpu, true); + + if (sched_smp_initialized) { + sched_domains_numa_masks_set(cpu); + cpuset_cpu_active(); + } + + /* + * Put the rq online, if not already. This happens: + * + * 1) In the early boot process, because we build the real domains + * after all cpus have been brought up. + * + * 2) At runtime, if cpuset_cpu_active() fails to rebuild the + * domains. + */ + raw_spin_lock_irqsave(&rq->lock, flags); + if (rq->rd) { + BUG_ON(!cpumask_test_cpu(cpu, rq->rd->span)); + set_rq_online(rq); + } + raw_spin_unlock_irqrestore(&rq->lock, flags); + + update_max_interval(); + + return 0; +} + +int sched_cpu_deactivate(unsigned int cpu) +{ + int ret; + + set_cpu_active(cpu, false); + /* + * We've cleared cpu_active_mask, wait for all preempt-disabled and RCU + * users of this state to go away such that all new such users will + * observe it. + * + * For CONFIG_PREEMPT we have preemptible RCU and its sync_rcu() might + * not imply sync_sched(), so wait for both. + * + * Do sync before park smpboot threads to take care the rcu boost case. + */ + if (IS_ENABLED(CONFIG_PREEMPT)) + synchronize_rcu_mult(call_rcu, call_rcu_sched); + else + synchronize_rcu(); + + if (!sched_smp_initialized) + return 0; + + ret = cpuset_cpu_inactive(cpu); + if (ret) { + set_cpu_active(cpu, true); + return ret; + } + sched_domains_numa_masks_clear(cpu); + return 0; +} + +static void sched_rq_cpu_starting(unsigned int cpu) +{ + struct rq *rq = cpu_rq(cpu); + + rq->calc_load_update = calc_load_update; + account_reset_rq(rq); + update_max_interval(); +} + +int sched_cpu_starting(unsigned int cpu) +{ + set_cpu_rq_start_time(cpu); + sched_rq_cpu_starting(cpu); + return 0; +} + +#ifdef CONFIG_HOTPLUG_CPU +int sched_cpu_dying(unsigned int cpu) +{ + struct rq *rq = cpu_rq(cpu); + unsigned long flags; + + /* Handle pending wakeups and then migrate everything off */ + sched_ttwu_pending(); + raw_spin_lock_irqsave(&rq->lock, flags); + if (rq->rd) { + BUG_ON(!cpumask_test_cpu(cpu, rq->rd->span)); + set_rq_offline(rq); + } + migrate_tasks(rq); + BUG_ON(rq->nr_running != 1); + raw_spin_unlock_irqrestore(&rq->lock, flags); + calc_load_migrate(rq); + update_max_interval(); + nohz_balance_exit_idle(cpu); + hrtick_clear(rq); + return 0; } +#endif void __init sched_init_smp(void) { @@ -7179,12 +7265,6 @@ void __init sched_init_smp(void) cpumask_set_cpu(smp_processor_id(), non_isolated_cpus); mutex_unlock(&sched_domains_mutex); - hotcpu_notifier(sched_domains_numa_masks_update, CPU_PRI_SCHED_ACTIVE); - hotcpu_notifier(cpuset_cpu_active, CPU_PRI_CPUSET_ACTIVE); - hotcpu_notifier(cpuset_cpu_inactive, CPU_PRI_CPUSET_INACTIVE); - - init_hrtick(); - /* Move init over to a non-isolated CPU */ if (set_cpus_allowed_ptr(current, non_isolated_cpus) < 0) BUG(); @@ -7193,7 +7273,16 @@ void __init sched_init_smp(void) init_sched_rt_class(); init_sched_dl_class(); + sched_smp_initialized = true; +} + +static int __init migration_init(void) +{ + sched_rq_cpu_starting(smp_processor_id()); + return 0; } +early_initcall(migration_init); + #else void __init sched_init_smp(void) { @@ -7328,8 +7417,6 @@ void __init sched_init(void) for (j = 0; j < CPU_LOAD_IDX_MAX; j++) rq->cpu_load[j] = 0; - rq->last_load_update_tick = jiffies; - #ifdef CONFIG_SMP rq->sd = NULL; rq->rd = NULL; @@ -7348,12 +7435,13 @@ void __init sched_init(void) rq_attach_root(rq, &def_root_domain); #ifdef CONFIG_NO_HZ_COMMON + rq->last_load_update_tick = jiffies; rq->nohz_flags = 0; #endif #ifdef CONFIG_NO_HZ_FULL rq->last_sched_tick = 0; #endif -#endif +#endif /* CONFIG_SMP */ init_rq_hrtick(rq); atomic_set(&rq->nr_iowait, 0); } @@ -7391,7 +7479,7 @@ void __init sched_init(void) if (cpu_isolated_map == NULL) zalloc_cpumask_var(&cpu_isolated_map, GFP_NOWAIT); idle_thread_set_boot_cpu(); - set_cpu_rq_start_time(); + set_cpu_rq_start_time(smp_processor_id()); #endif init_sched_fair_class(); @@ -7636,10 +7724,10 @@ void sched_move_task(struct task_struct *tsk) { struct task_group *tg; int queued, running; - unsigned long flags; + struct rq_flags rf; struct rq *rq; - rq = task_rq_lock(tsk, &flags); + rq = task_rq_lock(tsk, &rf); running = task_current(rq, tsk); queued = task_on_rq_queued(tsk); @@ -7671,7 +7759,7 @@ void sched_move_task(struct task_struct *tsk) if (queued) enqueue_task(rq, tsk, ENQUEUE_RESTORE | ENQUEUE_MOVE); - task_rq_unlock(rq, tsk, &flags); + task_rq_unlock(rq, tsk, &rf); } #endif /* CONFIG_CGROUP_SCHED */ @@ -7891,7 +7979,7 @@ static int sched_rt_can_attach(struct task_group *tg, struct task_struct *tsk) static int sched_rt_global_constraints(void) { unsigned long flags; - int i, ret = 0; + int i; raw_spin_lock_irqsave(&def_rt_bandwidth.rt_runtime_lock, flags); for_each_possible_cpu(i) { @@ -7903,7 +7991,7 @@ static int sched_rt_global_constraints(void) } raw_spin_unlock_irqrestore(&def_rt_bandwidth.rt_runtime_lock, flags); - return ret; + return 0; } #endif /* CONFIG_RT_GROUP_SCHED */ diff --git a/kernel/sched/cpuacct.c b/kernel/sched/cpuacct.c index 4a811203c04a..41f85c4d0938 100644 --- a/kernel/sched/cpuacct.c +++ b/kernel/sched/cpuacct.c @@ -25,11 +25,22 @@ enum cpuacct_stat_index { CPUACCT_STAT_NSTATS, }; +enum cpuacct_usage_index { + CPUACCT_USAGE_USER, /* ... user mode */ + CPUACCT_USAGE_SYSTEM, /* ... kernel mode */ + + CPUACCT_USAGE_NRUSAGE, +}; + +struct cpuacct_usage { + u64 usages[CPUACCT_USAGE_NRUSAGE]; +}; + /* track cpu usage of a group of tasks and its child groups */ struct cpuacct { struct cgroup_subsys_state css; /* cpuusage holds pointer to a u64-type object on every cpu */ - u64 __percpu *cpuusage; + struct cpuacct_usage __percpu *cpuusage; struct kernel_cpustat __percpu *cpustat; }; @@ -49,7 +60,7 @@ static inline struct cpuacct *parent_ca(struct cpuacct *ca) return css_ca(ca->css.parent); } -static DEFINE_PER_CPU(u64, root_cpuacct_cpuusage); +static DEFINE_PER_CPU(struct cpuacct_usage, root_cpuacct_cpuusage); static struct cpuacct root_cpuacct = { .cpustat = &kernel_cpustat, .cpuusage = &root_cpuacct_cpuusage, @@ -68,7 +79,7 @@ cpuacct_css_alloc(struct cgroup_subsys_state *parent_css) if (!ca) goto out; - ca->cpuusage = alloc_percpu(u64); + ca->cpuusage = alloc_percpu(struct cpuacct_usage); if (!ca->cpuusage) goto out_free_ca; @@ -96,20 +107,37 @@ static void cpuacct_css_free(struct cgroup_subsys_state *css) kfree(ca); } -static u64 cpuacct_cpuusage_read(struct cpuacct *ca, int cpu) +static u64 cpuacct_cpuusage_read(struct cpuacct *ca, int cpu, + enum cpuacct_usage_index index) { - u64 *cpuusage = per_cpu_ptr(ca->cpuusage, cpu); + struct cpuacct_usage *cpuusage = per_cpu_ptr(ca->cpuusage, cpu); u64 data; + /* + * We allow index == CPUACCT_USAGE_NRUSAGE here to read + * the sum of suages. + */ + BUG_ON(index > CPUACCT_USAGE_NRUSAGE); + #ifndef CONFIG_64BIT /* * Take rq->lock to make 64-bit read safe on 32-bit platforms. */ raw_spin_lock_irq(&cpu_rq(cpu)->lock); - data = *cpuusage; +#endif + + if (index == CPUACCT_USAGE_NRUSAGE) { + int i = 0; + + data = 0; + for (i = 0; i < CPUACCT_USAGE_NRUSAGE; i++) + data += cpuusage->usages[i]; + } else { + data = cpuusage->usages[index]; + } + +#ifndef CONFIG_64BIT raw_spin_unlock_irq(&cpu_rq(cpu)->lock); -#else - data = *cpuusage; #endif return data; @@ -117,69 +145,103 @@ static u64 cpuacct_cpuusage_read(struct cpuacct *ca, int cpu) static void cpuacct_cpuusage_write(struct cpuacct *ca, int cpu, u64 val) { - u64 *cpuusage = per_cpu_ptr(ca->cpuusage, cpu); + struct cpuacct_usage *cpuusage = per_cpu_ptr(ca->cpuusage, cpu); + int i; #ifndef CONFIG_64BIT /* * Take rq->lock to make 64-bit write safe on 32-bit platforms. */ raw_spin_lock_irq(&cpu_rq(cpu)->lock); - *cpuusage = val; +#endif + + for (i = 0; i < CPUACCT_USAGE_NRUSAGE; i++) + cpuusage->usages[i] = val; + +#ifndef CONFIG_64BIT raw_spin_unlock_irq(&cpu_rq(cpu)->lock); -#else - *cpuusage = val; #endif } /* return total cpu usage (in nanoseconds) of a group */ -static u64 cpuusage_read(struct cgroup_subsys_state *css, struct cftype *cft) +static u64 __cpuusage_read(struct cgroup_subsys_state *css, + enum cpuacct_usage_index index) { struct cpuacct *ca = css_ca(css); u64 totalcpuusage = 0; int i; - for_each_present_cpu(i) - totalcpuusage += cpuacct_cpuusage_read(ca, i); + for_each_possible_cpu(i) + totalcpuusage += cpuacct_cpuusage_read(ca, i, index); return totalcpuusage; } +static u64 cpuusage_user_read(struct cgroup_subsys_state *css, + struct cftype *cft) +{ + return __cpuusage_read(css, CPUACCT_USAGE_USER); +} + +static u64 cpuusage_sys_read(struct cgroup_subsys_state *css, + struct cftype *cft) +{ + return __cpuusage_read(css, CPUACCT_USAGE_SYSTEM); +} + +static u64 cpuusage_read(struct cgroup_subsys_state *css, struct cftype *cft) +{ + return __cpuusage_read(css, CPUACCT_USAGE_NRUSAGE); +} + static int cpuusage_write(struct cgroup_subsys_state *css, struct cftype *cft, u64 val) { struct cpuacct *ca = css_ca(css); - int err = 0; - int i; + int cpu; /* * Only allow '0' here to do a reset. */ - if (val) { - err = -EINVAL; - goto out; - } + if (val) + return -EINVAL; - for_each_present_cpu(i) - cpuacct_cpuusage_write(ca, i, 0); + for_each_possible_cpu(cpu) + cpuacct_cpuusage_write(ca, cpu, 0); -out: - return err; + return 0; } -static int cpuacct_percpu_seq_show(struct seq_file *m, void *V) +static int __cpuacct_percpu_seq_show(struct seq_file *m, + enum cpuacct_usage_index index) { struct cpuacct *ca = css_ca(seq_css(m)); u64 percpu; int i; - for_each_present_cpu(i) { - percpu = cpuacct_cpuusage_read(ca, i); + for_each_possible_cpu(i) { + percpu = cpuacct_cpuusage_read(ca, i, index); seq_printf(m, "%llu ", (unsigned long long) percpu); } seq_printf(m, "\n"); return 0; } +static int cpuacct_percpu_user_seq_show(struct seq_file *m, void *V) +{ + return __cpuacct_percpu_seq_show(m, CPUACCT_USAGE_USER); +} + +static int cpuacct_percpu_sys_seq_show(struct seq_file *m, void *V) +{ + return __cpuacct_percpu_seq_show(m, CPUACCT_USAGE_SYSTEM); +} + +static int cpuacct_percpu_seq_show(struct seq_file *m, void *V) +{ + return __cpuacct_percpu_seq_show(m, CPUACCT_USAGE_NRUSAGE); +} + static const char * const cpuacct_stat_desc[] = { [CPUACCT_STAT_USER] = "user", [CPUACCT_STAT_SYSTEM] = "system", @@ -191,7 +253,7 @@ static int cpuacct_stats_show(struct seq_file *sf, void *v) int cpu; s64 val = 0; - for_each_online_cpu(cpu) { + for_each_possible_cpu(cpu) { struct kernel_cpustat *kcpustat = per_cpu_ptr(ca->cpustat, cpu); val += kcpustat->cpustat[CPUTIME_USER]; val += kcpustat->cpustat[CPUTIME_NICE]; @@ -200,7 +262,7 @@ static int cpuacct_stats_show(struct seq_file *sf, void *v) seq_printf(sf, "%s %lld\n", cpuacct_stat_desc[CPUACCT_STAT_USER], val); val = 0; - for_each_online_cpu(cpu) { + for_each_possible_cpu(cpu) { struct kernel_cpustat *kcpustat = per_cpu_ptr(ca->cpustat, cpu); val += kcpustat->cpustat[CPUTIME_SYSTEM]; val += kcpustat->cpustat[CPUTIME_IRQ]; @@ -220,10 +282,26 @@ static struct cftype files[] = { .write_u64 = cpuusage_write, }, { + .name = "usage_user", + .read_u64 = cpuusage_user_read, + }, + { + .name = "usage_sys", + .read_u64 = cpuusage_sys_read, + }, + { .name = "usage_percpu", .seq_show = cpuacct_percpu_seq_show, }, { + .name = "usage_percpu_user", + .seq_show = cpuacct_percpu_user_seq_show, + }, + { + .name = "usage_percpu_sys", + .seq_show = cpuacct_percpu_sys_seq_show, + }, + { .name = "stat", .seq_show = cpuacct_stats_show, }, @@ -238,10 +316,17 @@ static struct cftype files[] = { void cpuacct_charge(struct task_struct *tsk, u64 cputime) { struct cpuacct *ca; + int index = CPUACCT_USAGE_SYSTEM; + struct pt_regs *regs = task_pt_regs(tsk); + + if (regs && user_mode(regs)) + index = CPUACCT_USAGE_USER; rcu_read_lock(); + for (ca = task_ca(tsk); ca; ca = parent_ca(ca)) - *this_cpu_ptr(ca->cpuusage) += cputime; + this_cpu_ptr(ca->cpuusage)->usages[index] += cputime; + rcu_read_unlock(); } diff --git a/kernel/sched/cpudeadline.c b/kernel/sched/cpudeadline.c index 5a75b08cfd85..5be58820465c 100644 --- a/kernel/sched/cpudeadline.c +++ b/kernel/sched/cpudeadline.c @@ -103,10 +103,10 @@ int cpudl_find(struct cpudl *cp, struct task_struct *p, const struct sched_dl_entity *dl_se = &p->dl; if (later_mask && - cpumask_and(later_mask, cp->free_cpus, &p->cpus_allowed)) { + cpumask_and(later_mask, cp->free_cpus, tsk_cpus_allowed(p))) { best_cpu = cpumask_any(later_mask); goto out; - } else if (cpumask_test_cpu(cpudl_maximum(cp), &p->cpus_allowed) && + } else if (cpumask_test_cpu(cpudl_maximum(cp), tsk_cpus_allowed(p)) && dl_time_before(dl_se->deadline, cp->elements[0].dl)) { best_cpu = cpudl_maximum(cp); if (later_mask) diff --git a/kernel/sched/cpufreq.c b/kernel/sched/cpufreq.c index 928c4ba32f68..1141954e73b4 100644 --- a/kernel/sched/cpufreq.c +++ b/kernel/sched/cpufreq.c @@ -14,24 +14,50 @@ DEFINE_PER_CPU(struct update_util_data *, cpufreq_update_util_data); /** - * cpufreq_set_update_util_data - Populate the CPU's update_util_data pointer. + * cpufreq_add_update_util_hook - Populate the CPU's update_util_data pointer. * @cpu: The CPU to set the pointer for. * @data: New pointer value. + * @func: Callback function to set for the CPU. * - * Set and publish the update_util_data pointer for the given CPU. That pointer - * points to a struct update_util_data object containing a callback function - * to call from cpufreq_update_util(). That function will be called from an RCU - * read-side critical section, so it must not sleep. + * Set and publish the update_util_data pointer for the given CPU. * - * Callers must use RCU-sched callbacks to free any memory that might be - * accessed via the old update_util_data pointer or invoke synchronize_sched() - * right after this function to avoid use-after-free. + * The update_util_data pointer of @cpu is set to @data and the callback + * function pointer in the target struct update_util_data is set to @func. + * That function will be called by cpufreq_update_util() from RCU-sched + * read-side critical sections, so it must not sleep. @data will always be + * passed to it as the first argument which allows the function to get to the + * target update_util_data structure and its container. + * + * The update_util_data pointer of @cpu must be NULL when this function is + * called or it will WARN() and return with no effect. */ -void cpufreq_set_update_util_data(int cpu, struct update_util_data *data) +void cpufreq_add_update_util_hook(int cpu, struct update_util_data *data, + void (*func)(struct update_util_data *data, u64 time, + unsigned long util, unsigned long max)) { - if (WARN_ON(data && !data->func)) + if (WARN_ON(!data || !func)) return; + if (WARN_ON(per_cpu(cpufreq_update_util_data, cpu))) + return; + + data->func = func; rcu_assign_pointer(per_cpu(cpufreq_update_util_data, cpu), data); } -EXPORT_SYMBOL_GPL(cpufreq_set_update_util_data); +EXPORT_SYMBOL_GPL(cpufreq_add_update_util_hook); + +/** + * cpufreq_remove_update_util_hook - Clear the CPU's update_util_data pointer. + * @cpu: The CPU to clear the pointer for. + * + * Clear the update_util_data pointer for the given CPU. + * + * Callers must use RCU-sched callbacks to free any memory that might be + * accessed via the old update_util_data pointer or invoke synchronize_sched() + * right after this function to avoid use-after-free. + */ +void cpufreq_remove_update_util_hook(int cpu) +{ + rcu_assign_pointer(per_cpu(cpufreq_update_util_data, cpu), NULL); +} +EXPORT_SYMBOL_GPL(cpufreq_remove_update_util_hook); diff --git a/kernel/sched/cpufreq_schedutil.c b/kernel/sched/cpufreq_schedutil.c new file mode 100644 index 000000000000..154ae3a51e86 --- /dev/null +++ b/kernel/sched/cpufreq_schedutil.c @@ -0,0 +1,530 @@ +/* + * CPUFreq governor based on scheduler-provided CPU utilization data. + * + * Copyright (C) 2016, Intel Corporation + * Author: Rafael J. Wysocki <rafael.j.wysocki@intel.com> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +#include <linux/cpufreq.h> +#include <linux/module.h> +#include <linux/slab.h> +#include <trace/events/power.h> + +#include "sched.h" + +struct sugov_tunables { + struct gov_attr_set attr_set; + unsigned int rate_limit_us; +}; + +struct sugov_policy { + struct cpufreq_policy *policy; + + struct sugov_tunables *tunables; + struct list_head tunables_hook; + + raw_spinlock_t update_lock; /* For shared policies */ + u64 last_freq_update_time; + s64 freq_update_delay_ns; + unsigned int next_freq; + + /* The next fields are only needed if fast switch cannot be used. */ + struct irq_work irq_work; + struct work_struct work; + struct mutex work_lock; + bool work_in_progress; + + bool need_freq_update; +}; + +struct sugov_cpu { + struct update_util_data update_util; + struct sugov_policy *sg_policy; + + /* The fields below are only needed when sharing a policy. */ + unsigned long util; + unsigned long max; + u64 last_update; +}; + +static DEFINE_PER_CPU(struct sugov_cpu, sugov_cpu); + +/************************ Governor internals ***********************/ + +static bool sugov_should_update_freq(struct sugov_policy *sg_policy, u64 time) +{ + s64 delta_ns; + + if (sg_policy->work_in_progress) + return false; + + if (unlikely(sg_policy->need_freq_update)) { + sg_policy->need_freq_update = false; + /* + * This happens when limits change, so forget the previous + * next_freq value and force an update. + */ + sg_policy->next_freq = UINT_MAX; + return true; + } + + delta_ns = time - sg_policy->last_freq_update_time; + return delta_ns >= sg_policy->freq_update_delay_ns; +} + +static void sugov_update_commit(struct sugov_policy *sg_policy, u64 time, + unsigned int next_freq) +{ + struct cpufreq_policy *policy = sg_policy->policy; + + sg_policy->last_freq_update_time = time; + + if (policy->fast_switch_enabled) { + if (sg_policy->next_freq == next_freq) { + trace_cpu_frequency(policy->cur, smp_processor_id()); + return; + } + sg_policy->next_freq = next_freq; + next_freq = cpufreq_driver_fast_switch(policy, next_freq); + if (next_freq == CPUFREQ_ENTRY_INVALID) + return; + + policy->cur = next_freq; + trace_cpu_frequency(next_freq, smp_processor_id()); + } else if (sg_policy->next_freq != next_freq) { + sg_policy->next_freq = next_freq; + sg_policy->work_in_progress = true; + irq_work_queue(&sg_policy->irq_work); + } +} + +/** + * get_next_freq - Compute a new frequency for a given cpufreq policy. + * @policy: cpufreq policy object to compute the new frequency for. + * @util: Current CPU utilization. + * @max: CPU capacity. + * + * If the utilization is frequency-invariant, choose the new frequency to be + * proportional to it, that is + * + * next_freq = C * max_freq * util / max + * + * Otherwise, approximate the would-be frequency-invariant utilization by + * util_raw * (curr_freq / max_freq) which leads to + * + * next_freq = C * curr_freq * util_raw / max + * + * Take C = 1.25 for the frequency tipping point at (util / max) = 0.8. + */ +static unsigned int get_next_freq(struct cpufreq_policy *policy, + unsigned long util, unsigned long max) +{ + unsigned int freq = arch_scale_freq_invariant() ? + policy->cpuinfo.max_freq : policy->cur; + + return (freq + (freq >> 2)) * util / max; +} + +static void sugov_update_single(struct update_util_data *hook, u64 time, + unsigned long util, unsigned long max) +{ + struct sugov_cpu *sg_cpu = container_of(hook, struct sugov_cpu, update_util); + struct sugov_policy *sg_policy = sg_cpu->sg_policy; + struct cpufreq_policy *policy = sg_policy->policy; + unsigned int next_f; + + if (!sugov_should_update_freq(sg_policy, time)) + return; + + next_f = util == ULONG_MAX ? policy->cpuinfo.max_freq : + get_next_freq(policy, util, max); + sugov_update_commit(sg_policy, time, next_f); +} + +static unsigned int sugov_next_freq_shared(struct sugov_policy *sg_policy, + unsigned long util, unsigned long max) +{ + struct cpufreq_policy *policy = sg_policy->policy; + unsigned int max_f = policy->cpuinfo.max_freq; + u64 last_freq_update_time = sg_policy->last_freq_update_time; + unsigned int j; + + if (util == ULONG_MAX) + return max_f; + + for_each_cpu(j, policy->cpus) { + struct sugov_cpu *j_sg_cpu; + unsigned long j_util, j_max; + s64 delta_ns; + + if (j == smp_processor_id()) + continue; + + j_sg_cpu = &per_cpu(sugov_cpu, j); + /* + * If the CPU utilization was last updated before the previous + * frequency update and the time elapsed between the last update + * of the CPU utilization and the last frequency update is long + * enough, don't take the CPU into account as it probably is + * idle now. + */ + delta_ns = last_freq_update_time - j_sg_cpu->last_update; + if (delta_ns > TICK_NSEC) + continue; + + j_util = j_sg_cpu->util; + if (j_util == ULONG_MAX) + return max_f; + + j_max = j_sg_cpu->max; + if (j_util * max > j_max * util) { + util = j_util; + max = j_max; + } + } + + return get_next_freq(policy, util, max); +} + +static void sugov_update_shared(struct update_util_data *hook, u64 time, + unsigned long util, unsigned long max) +{ + struct sugov_cpu *sg_cpu = container_of(hook, struct sugov_cpu, update_util); + struct sugov_policy *sg_policy = sg_cpu->sg_policy; + unsigned int next_f; + + raw_spin_lock(&sg_policy->update_lock); + + sg_cpu->util = util; + sg_cpu->max = max; + sg_cpu->last_update = time; + + if (sugov_should_update_freq(sg_policy, time)) { + next_f = sugov_next_freq_shared(sg_policy, util, max); + sugov_update_commit(sg_policy, time, next_f); + } + + raw_spin_unlock(&sg_policy->update_lock); +} + +static void sugov_work(struct work_struct *work) +{ + struct sugov_policy *sg_policy = container_of(work, struct sugov_policy, work); + + mutex_lock(&sg_policy->work_lock); + __cpufreq_driver_target(sg_policy->policy, sg_policy->next_freq, + CPUFREQ_RELATION_L); + mutex_unlock(&sg_policy->work_lock); + + sg_policy->work_in_progress = false; +} + +static void sugov_irq_work(struct irq_work *irq_work) +{ + struct sugov_policy *sg_policy; + + sg_policy = container_of(irq_work, struct sugov_policy, irq_work); + schedule_work_on(smp_processor_id(), &sg_policy->work); +} + +/************************** sysfs interface ************************/ + +static struct sugov_tunables *global_tunables; +static DEFINE_MUTEX(global_tunables_lock); + +static inline struct sugov_tunables *to_sugov_tunables(struct gov_attr_set *attr_set) +{ + return container_of(attr_set, struct sugov_tunables, attr_set); +} + +static ssize_t rate_limit_us_show(struct gov_attr_set *attr_set, char *buf) +{ + struct sugov_tunables *tunables = to_sugov_tunables(attr_set); + + return sprintf(buf, "%u\n", tunables->rate_limit_us); +} + +static ssize_t rate_limit_us_store(struct gov_attr_set *attr_set, const char *buf, + size_t count) +{ + struct sugov_tunables *tunables = to_sugov_tunables(attr_set); + struct sugov_policy *sg_policy; + unsigned int rate_limit_us; + + if (kstrtouint(buf, 10, &rate_limit_us)) + return -EINVAL; + + tunables->rate_limit_us = rate_limit_us; + + list_for_each_entry(sg_policy, &attr_set->policy_list, tunables_hook) + sg_policy->freq_update_delay_ns = rate_limit_us * NSEC_PER_USEC; + + return count; +} + +static struct governor_attr rate_limit_us = __ATTR_RW(rate_limit_us); + +static struct attribute *sugov_attributes[] = { + &rate_limit_us.attr, + NULL +}; + +static struct kobj_type sugov_tunables_ktype = { + .default_attrs = sugov_attributes, + .sysfs_ops = &governor_sysfs_ops, +}; + +/********************** cpufreq governor interface *********************/ + +static struct cpufreq_governor schedutil_gov; + +static struct sugov_policy *sugov_policy_alloc(struct cpufreq_policy *policy) +{ + struct sugov_policy *sg_policy; + + sg_policy = kzalloc(sizeof(*sg_policy), GFP_KERNEL); + if (!sg_policy) + return NULL; + + sg_policy->policy = policy; + init_irq_work(&sg_policy->irq_work, sugov_irq_work); + INIT_WORK(&sg_policy->work, sugov_work); + mutex_init(&sg_policy->work_lock); + raw_spin_lock_init(&sg_policy->update_lock); + return sg_policy; +} + +static void sugov_policy_free(struct sugov_policy *sg_policy) +{ + mutex_destroy(&sg_policy->work_lock); + kfree(sg_policy); +} + +static struct sugov_tunables *sugov_tunables_alloc(struct sugov_policy *sg_policy) +{ + struct sugov_tunables *tunables; + + tunables = kzalloc(sizeof(*tunables), GFP_KERNEL); + if (tunables) { + gov_attr_set_init(&tunables->attr_set, &sg_policy->tunables_hook); + if (!have_governor_per_policy()) + global_tunables = tunables; + } + return tunables; +} + +static void sugov_tunables_free(struct sugov_tunables *tunables) +{ + if (!have_governor_per_policy()) + global_tunables = NULL; + + kfree(tunables); +} + +static int sugov_init(struct cpufreq_policy *policy) +{ + struct sugov_policy *sg_policy; + struct sugov_tunables *tunables; + unsigned int lat; + int ret = 0; + + /* State should be equivalent to EXIT */ + if (policy->governor_data) + return -EBUSY; + + sg_policy = sugov_policy_alloc(policy); + if (!sg_policy) + return -ENOMEM; + + mutex_lock(&global_tunables_lock); + + if (global_tunables) { + if (WARN_ON(have_governor_per_policy())) { + ret = -EINVAL; + goto free_sg_policy; + } + policy->governor_data = sg_policy; + sg_policy->tunables = global_tunables; + + gov_attr_set_get(&global_tunables->attr_set, &sg_policy->tunables_hook); + goto out; + } + + tunables = sugov_tunables_alloc(sg_policy); + if (!tunables) { + ret = -ENOMEM; + goto free_sg_policy; + } + + tunables->rate_limit_us = LATENCY_MULTIPLIER; + lat = policy->cpuinfo.transition_latency / NSEC_PER_USEC; + if (lat) + tunables->rate_limit_us *= lat; + + policy->governor_data = sg_policy; + sg_policy->tunables = tunables; + + ret = kobject_init_and_add(&tunables->attr_set.kobj, &sugov_tunables_ktype, + get_governor_parent_kobj(policy), "%s", + schedutil_gov.name); + if (ret) + goto fail; + + out: + mutex_unlock(&global_tunables_lock); + + cpufreq_enable_fast_switch(policy); + return 0; + + fail: + policy->governor_data = NULL; + sugov_tunables_free(tunables); + + free_sg_policy: + mutex_unlock(&global_tunables_lock); + + sugov_policy_free(sg_policy); + pr_err("cpufreq: schedutil governor initialization failed (error %d)\n", ret); + return ret; +} + +static int sugov_exit(struct cpufreq_policy *policy) +{ + struct sugov_policy *sg_policy = policy->governor_data; + struct sugov_tunables *tunables = sg_policy->tunables; + unsigned int count; + + cpufreq_disable_fast_switch(policy); + + mutex_lock(&global_tunables_lock); + + count = gov_attr_set_put(&tunables->attr_set, &sg_policy->tunables_hook); + policy->governor_data = NULL; + if (!count) + sugov_tunables_free(tunables); + + mutex_unlock(&global_tunables_lock); + + sugov_policy_free(sg_policy); + return 0; +} + +static int sugov_start(struct cpufreq_policy *policy) +{ + struct sugov_policy *sg_policy = policy->governor_data; + unsigned int cpu; + + sg_policy->freq_update_delay_ns = sg_policy->tunables->rate_limit_us * NSEC_PER_USEC; + sg_policy->last_freq_update_time = 0; + sg_policy->next_freq = UINT_MAX; + sg_policy->work_in_progress = false; + sg_policy->need_freq_update = false; + + for_each_cpu(cpu, policy->cpus) { + struct sugov_cpu *sg_cpu = &per_cpu(sugov_cpu, cpu); + + sg_cpu->sg_policy = sg_policy; + if (policy_is_shared(policy)) { + sg_cpu->util = ULONG_MAX; + sg_cpu->max = 0; + sg_cpu->last_update = 0; + cpufreq_add_update_util_hook(cpu, &sg_cpu->update_util, + sugov_update_shared); + } else { + cpufreq_add_update_util_hook(cpu, &sg_cpu->update_util, + sugov_update_single); + } + } + return 0; +} + +static int sugov_stop(struct cpufreq_policy *policy) +{ + struct sugov_policy *sg_policy = policy->governor_data; + unsigned int cpu; + + for_each_cpu(cpu, policy->cpus) + cpufreq_remove_update_util_hook(cpu); + + synchronize_sched(); + + irq_work_sync(&sg_policy->irq_work); + cancel_work_sync(&sg_policy->work); + return 0; +} + +static int sugov_limits(struct cpufreq_policy *policy) +{ + struct sugov_policy *sg_policy = policy->governor_data; + + if (!policy->fast_switch_enabled) { + mutex_lock(&sg_policy->work_lock); + + if (policy->max < policy->cur) + __cpufreq_driver_target(policy, policy->max, + CPUFREQ_RELATION_H); + else if (policy->min > policy->cur) + __cpufreq_driver_target(policy, policy->min, + CPUFREQ_RELATION_L); + + mutex_unlock(&sg_policy->work_lock); + } + + sg_policy->need_freq_update = true; + return 0; +} + +int sugov_governor(struct cpufreq_policy *policy, unsigned int event) +{ + if (event == CPUFREQ_GOV_POLICY_INIT) { + return sugov_init(policy); + } else if (policy->governor_data) { + switch (event) { + case CPUFREQ_GOV_POLICY_EXIT: + return sugov_exit(policy); + case CPUFREQ_GOV_START: + return sugov_start(policy); + case CPUFREQ_GOV_STOP: + return sugov_stop(policy); + case CPUFREQ_GOV_LIMITS: + return sugov_limits(policy); + } + } + return -EINVAL; +} + +static struct cpufreq_governor schedutil_gov = { + .name = "schedutil", + .governor = sugov_governor, + .owner = THIS_MODULE, +}; + +static int __init sugov_module_init(void) +{ + return cpufreq_register_governor(&schedutil_gov); +} + +static void __exit sugov_module_exit(void) +{ + cpufreq_unregister_governor(&schedutil_gov); +} + +MODULE_AUTHOR("Rafael J. Wysocki <rafael.j.wysocki@intel.com>"); +MODULE_DESCRIPTION("Utilization-based CPU frequency selection"); +MODULE_LICENSE("GPL"); + +#ifdef CONFIG_CPU_FREQ_DEFAULT_GOV_SCHEDUTIL +struct cpufreq_governor *cpufreq_default_governor(void) +{ + return &schedutil_gov; +} + +fs_initcall(sugov_module_init); +#else +module_init(sugov_module_init); +#endif +module_exit(sugov_module_exit); diff --git a/kernel/sched/cpupri.c b/kernel/sched/cpupri.c index 981fcd7dc394..11e9705bf937 100644 --- a/kernel/sched/cpupri.c +++ b/kernel/sched/cpupri.c @@ -103,11 +103,11 @@ int cpupri_find(struct cpupri *cp, struct task_struct *p, if (skip) continue; - if (cpumask_any_and(&p->cpus_allowed, vec->mask) >= nr_cpu_ids) + if (cpumask_any_and(tsk_cpus_allowed(p), vec->mask) >= nr_cpu_ids) continue; if (lowest_mask) { - cpumask_and(lowest_mask, &p->cpus_allowed, vec->mask); + cpumask_and(lowest_mask, tsk_cpus_allowed(p), vec->mask); /* * We have to ensure that we have at least one bit diff --git a/kernel/sched/deadline.c b/kernel/sched/deadline.c index affd97ec9f65..fcb7f0217ff4 100644 --- a/kernel/sched/deadline.c +++ b/kernel/sched/deadline.c @@ -134,7 +134,7 @@ static void inc_dl_migration(struct sched_dl_entity *dl_se, struct dl_rq *dl_rq) { struct task_struct *p = dl_task_of(dl_se); - if (p->nr_cpus_allowed > 1) + if (tsk_nr_cpus_allowed(p) > 1) dl_rq->dl_nr_migratory++; update_dl_migration(dl_rq); @@ -144,7 +144,7 @@ static void dec_dl_migration(struct sched_dl_entity *dl_se, struct dl_rq *dl_rq) { struct task_struct *p = dl_task_of(dl_se); - if (p->nr_cpus_allowed > 1) + if (tsk_nr_cpus_allowed(p) > 1) dl_rq->dl_nr_migratory--; update_dl_migration(dl_rq); @@ -591,10 +591,10 @@ static enum hrtimer_restart dl_task_timer(struct hrtimer *timer) struct sched_dl_entity, dl_timer); struct task_struct *p = dl_task_of(dl_se); - unsigned long flags; + struct rq_flags rf; struct rq *rq; - rq = task_rq_lock(p, &flags); + rq = task_rq_lock(p, &rf); /* * The task might have changed its scheduling policy to something @@ -670,14 +670,14 @@ static enum hrtimer_restart dl_task_timer(struct hrtimer *timer) * Nothing relies on rq->lock after this, so its safe to drop * rq->lock. */ - lockdep_unpin_lock(&rq->lock); + lockdep_unpin_lock(&rq->lock, rf.cookie); push_dl_task(rq); - lockdep_pin_lock(&rq->lock); + lockdep_repin_lock(&rq->lock, rf.cookie); } #endif unlock: - task_rq_unlock(rq, p, &flags); + task_rq_unlock(rq, p, &rf); /* * This can free the task_struct, including this hrtimer, do not touch @@ -717,10 +717,6 @@ static void update_curr_dl(struct rq *rq) if (!dl_task(curr) || !on_dl_rq(dl_se)) return; - /* Kick cpufreq (see the comment in linux/cpufreq.h). */ - if (cpu_of(rq) == smp_processor_id()) - cpufreq_trigger_update(rq_clock(rq)); - /* * Consumed budget is computed considering the time as * observed by schedulable tasks (excluding time spent @@ -736,6 +732,10 @@ static void update_curr_dl(struct rq *rq) return; } + /* kick cpufreq (see the comment in linux/cpufreq.h). */ + if (cpu_of(rq) == smp_processor_id()) + cpufreq_trigger_update(rq_clock(rq)); + schedstat_set(curr->se.statistics.exec_max, max(curr->se.statistics.exec_max, delta_exec)); @@ -966,7 +966,7 @@ static void enqueue_task_dl(struct rq *rq, struct task_struct *p, int flags) enqueue_dl_entity(&p->dl, pi_se, flags); - if (!task_current(rq, p) && p->nr_cpus_allowed > 1) + if (!task_current(rq, p) && tsk_nr_cpus_allowed(p) > 1) enqueue_pushable_dl_task(rq, p); } @@ -1040,9 +1040,9 @@ select_task_rq_dl(struct task_struct *p, int cpu, int sd_flag, int flags) * try to make it stay here, it might be important. */ if (unlikely(dl_task(curr)) && - (curr->nr_cpus_allowed < 2 || + (tsk_nr_cpus_allowed(curr) < 2 || !dl_entity_preempt(&p->dl, &curr->dl)) && - (p->nr_cpus_allowed > 1)) { + (tsk_nr_cpus_allowed(p) > 1)) { int target = find_later_rq(p); if (target != -1 && @@ -1063,7 +1063,7 @@ static void check_preempt_equal_dl(struct rq *rq, struct task_struct *p) * Current can't be migrated, useless to reschedule, * let's hope p can move out. */ - if (rq->curr->nr_cpus_allowed == 1 || + if (tsk_nr_cpus_allowed(rq->curr) == 1 || cpudl_find(&rq->rd->cpudl, rq->curr, NULL) == -1) return; @@ -1071,7 +1071,7 @@ static void check_preempt_equal_dl(struct rq *rq, struct task_struct *p) * p is migratable, so let's not schedule it and * see if it is pushed or pulled somewhere else. */ - if (p->nr_cpus_allowed != 1 && + if (tsk_nr_cpus_allowed(p) != 1 && cpudl_find(&rq->rd->cpudl, p, NULL) != -1) return; @@ -1125,7 +1125,8 @@ static struct sched_dl_entity *pick_next_dl_entity(struct rq *rq, return rb_entry(left, struct sched_dl_entity, rb_node); } -struct task_struct *pick_next_task_dl(struct rq *rq, struct task_struct *prev) +struct task_struct * +pick_next_task_dl(struct rq *rq, struct task_struct *prev, struct pin_cookie cookie) { struct sched_dl_entity *dl_se; struct task_struct *p; @@ -1140,9 +1141,9 @@ struct task_struct *pick_next_task_dl(struct rq *rq, struct task_struct *prev) * disabled avoiding further scheduler activity on it and we're * being very careful to re-start the picking loop. */ - lockdep_unpin_lock(&rq->lock); + lockdep_unpin_lock(&rq->lock, cookie); pull_dl_task(rq); - lockdep_pin_lock(&rq->lock); + lockdep_repin_lock(&rq->lock, cookie); /* * pull_rt_task() can drop (and re-acquire) rq->lock; this * means a stop task can slip in, in which case we need to @@ -1185,7 +1186,7 @@ static void put_prev_task_dl(struct rq *rq, struct task_struct *p) { update_curr_dl(rq); - if (on_dl_rq(&p->dl) && p->nr_cpus_allowed > 1) + if (on_dl_rq(&p->dl) && tsk_nr_cpus_allowed(p) > 1) enqueue_pushable_dl_task(rq, p); } @@ -1286,7 +1287,7 @@ static int find_later_rq(struct task_struct *task) if (unlikely(!later_mask)) return -1; - if (task->nr_cpus_allowed == 1) + if (tsk_nr_cpus_allowed(task) == 1) return -1; /* @@ -1392,8 +1393,9 @@ static struct rq *find_lock_later_rq(struct task_struct *task, struct rq *rq) if (double_lock_balance(rq, later_rq)) { if (unlikely(task_rq(task) != rq || !cpumask_test_cpu(later_rq->cpu, - &task->cpus_allowed) || + tsk_cpus_allowed(task)) || task_running(rq, task) || + !dl_task(task) || !task_on_rq_queued(task))) { double_unlock_balance(rq, later_rq); later_rq = NULL; @@ -1431,7 +1433,7 @@ static struct task_struct *pick_next_pushable_dl_task(struct rq *rq) BUG_ON(rq->cpu != task_cpu(p)); BUG_ON(task_current(rq, p)); - BUG_ON(p->nr_cpus_allowed <= 1); + BUG_ON(tsk_nr_cpus_allowed(p) <= 1); BUG_ON(!task_on_rq_queued(p)); BUG_ON(!dl_task(p)); @@ -1470,7 +1472,7 @@ retry: */ if (dl_task(rq->curr) && dl_time_before(next_task->dl.deadline, rq->curr->dl.deadline) && - rq->curr->nr_cpus_allowed > 1) { + tsk_nr_cpus_allowed(rq->curr) > 1) { resched_curr(rq); return 0; } @@ -1617,9 +1619,9 @@ static void task_woken_dl(struct rq *rq, struct task_struct *p) { if (!task_running(rq, p) && !test_tsk_need_resched(rq->curr) && - p->nr_cpus_allowed > 1 && + tsk_nr_cpus_allowed(p) > 1 && dl_task(rq->curr) && - (rq->curr->nr_cpus_allowed < 2 || + (tsk_nr_cpus_allowed(rq->curr) < 2 || !dl_entity_preempt(&p->dl, &rq->curr->dl))) { push_dl_tasks(rq); } @@ -1723,7 +1725,7 @@ static void switched_to_dl(struct rq *rq, struct task_struct *p) if (task_on_rq_queued(p) && rq->curr != p) { #ifdef CONFIG_SMP - if (p->nr_cpus_allowed > 1 && rq->dl.overloaded) + if (tsk_nr_cpus_allowed(p) > 1 && rq->dl.overloaded) queue_push_tasks(rq); #else if (dl_task(rq->curr)) diff --git a/kernel/sched/debug.c b/kernel/sched/debug.c index 4fbc3bd5ff60..cf905f655ba1 100644 --- a/kernel/sched/debug.c +++ b/kernel/sched/debug.c @@ -626,15 +626,16 @@ do { \ #undef P #undef PN -#ifdef CONFIG_SCHEDSTATS -#define P(n) SEQ_printf(m, " .%-30s: %d\n", #n, rq->n); -#define P64(n) SEQ_printf(m, " .%-30s: %Ld\n", #n, rq->n); - #ifdef CONFIG_SMP +#define P64(n) SEQ_printf(m, " .%-30s: %Ld\n", #n, rq->n); P64(avg_idle); P64(max_idle_balance_cost); +#undef P64 #endif +#ifdef CONFIG_SCHEDSTATS +#define P(n) SEQ_printf(m, " .%-30s: %d\n", #n, rq->n); + if (schedstat_enabled()) { P(yld_count); P(sched_count); @@ -644,7 +645,6 @@ do { \ } #undef P -#undef P64 #endif spin_lock_irqsave(&sched_debug_lock, flags); print_cfs_stats(m, cpu); diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index 0fe30e66aff1..218f8e83db73 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -204,7 +204,7 @@ static void __update_inv_weight(struct load_weight *lw) * OR * (delta_exec * (weight * lw->inv_weight)) >> WMULT_SHIFT * - * Either weight := NICE_0_LOAD and lw \e prio_to_wmult[], in which case + * Either weight := NICE_0_LOAD and lw \e sched_prio_to_wmult[], in which case * we're guaranteed shift stays positive because inv_weight is guaranteed to * fit 32 bits, and NICE_0_LOAD gives another 10 bits; therefore shift >= 22. * @@ -682,17 +682,68 @@ void init_entity_runnable_average(struct sched_entity *se) sa->period_contrib = 1023; sa->load_avg = scale_load_down(se->load.weight); sa->load_sum = sa->load_avg * LOAD_AVG_MAX; - sa->util_avg = scale_load_down(SCHED_LOAD_SCALE); - sa->util_sum = sa->util_avg * LOAD_AVG_MAX; + /* + * At this point, util_avg won't be used in select_task_rq_fair anyway + */ + sa->util_avg = 0; + sa->util_sum = 0; /* when this task enqueue'ed, it will contribute to its cfs_rq's load_avg */ } +/* + * With new tasks being created, their initial util_avgs are extrapolated + * based on the cfs_rq's current util_avg: + * + * util_avg = cfs_rq->util_avg / (cfs_rq->load_avg + 1) * se.load.weight + * + * However, in many cases, the above util_avg does not give a desired + * value. Moreover, the sum of the util_avgs may be divergent, such + * as when the series is a harmonic series. + * + * To solve this problem, we also cap the util_avg of successive tasks to + * only 1/2 of the left utilization budget: + * + * util_avg_cap = (1024 - cfs_rq->avg.util_avg) / 2^n + * + * where n denotes the nth task. + * + * For example, a simplest series from the beginning would be like: + * + * task util_avg: 512, 256, 128, 64, 32, 16, 8, ... + * cfs_rq util_avg: 512, 768, 896, 960, 992, 1008, 1016, ... + * + * Finally, that extrapolated util_avg is clamped to the cap (util_avg_cap) + * if util_avg > util_avg_cap. + */ +void post_init_entity_util_avg(struct sched_entity *se) +{ + struct cfs_rq *cfs_rq = cfs_rq_of(se); + struct sched_avg *sa = &se->avg; + long cap = (long)(SCHED_CAPACITY_SCALE - cfs_rq->avg.util_avg) / 2; + + if (cap > 0) { + if (cfs_rq->avg.util_avg != 0) { + sa->util_avg = cfs_rq->avg.util_avg * se->load.weight; + sa->util_avg /= (cfs_rq->avg.load_avg + 1); + + if (sa->util_avg > cap) + sa->util_avg = cap; + } else { + sa->util_avg = cap; + } + sa->util_sum = sa->util_avg * LOAD_AVG_MAX; + } +} + static inline unsigned long cfs_rq_runnable_load_avg(struct cfs_rq *cfs_rq); static inline unsigned long cfs_rq_load_avg(struct cfs_rq *cfs_rq); #else void init_entity_runnable_average(struct sched_entity *se) { } +void post_init_entity_util_avg(struct sched_entity *se) +{ +} #endif /* @@ -2437,10 +2488,12 @@ account_entity_dequeue(struct cfs_rq *cfs_rq, struct sched_entity *se) update_load_sub(&cfs_rq->load, se->load.weight); if (!parent_entity(se)) update_load_sub(&rq_of(cfs_rq)->load, se->load.weight); +#ifdef CONFIG_SMP if (entity_is_task(se)) { account_numa_dequeue(rq_of(cfs_rq), task_of(se)); list_del_init(&se->group_node); } +#endif cfs_rq->nr_running--; } @@ -2550,6 +2603,16 @@ static const u32 runnable_avg_yN_sum[] = { }; /* + * Precomputed \Sum y^k { 1<=k<=n, where n%32=0). Values are rolled down to + * lower integers. See Documentation/scheduler/sched-avg.txt how these + * were generated: + */ +static const u32 __accumulated_sum_N32[] = { + 0, 23371, 35056, 40899, 43820, 45281, + 46011, 46376, 46559, 46650, 46696, 46719, +}; + +/* * Approximate: * val * y^n, where y^32 ~= 0.5 (~1 scheduling period) */ @@ -2597,22 +2660,13 @@ static u32 __compute_runnable_contrib(u64 n) else if (unlikely(n >= LOAD_AVG_MAX_N)) return LOAD_AVG_MAX; - /* Compute \Sum k^n combining precomputed values for k^i, \Sum k^j */ - do { - contrib /= 2; /* y^LOAD_AVG_PERIOD = 1/2 */ - contrib += runnable_avg_yN_sum[LOAD_AVG_PERIOD]; - - n -= LOAD_AVG_PERIOD; - } while (n > LOAD_AVG_PERIOD); - + /* Since n < LOAD_AVG_MAX_N, n/LOAD_AVG_PERIOD < 11 */ + contrib = __accumulated_sum_N32[n/LOAD_AVG_PERIOD]; + n %= LOAD_AVG_PERIOD; contrib = decay_load(contrib, n); return contrib + runnable_avg_yN_sum[n]; } -#if (SCHED_LOAD_SHIFT - SCHED_LOAD_RESOLUTION) != 10 || SCHED_CAPACITY_SHIFT != 10 -#error "load tracking assumes 2^10 as unit" -#endif - #define cap_scale(v, s) ((v)*(s) >> SCHED_CAPACITY_SHIFT) /* @@ -2821,23 +2875,54 @@ static inline void update_tg_load_avg(struct cfs_rq *cfs_rq, int force) {} static inline u64 cfs_rq_clock_task(struct cfs_rq *cfs_rq); +static inline void cfs_rq_util_change(struct cfs_rq *cfs_rq) +{ + struct rq *rq = rq_of(cfs_rq); + int cpu = cpu_of(rq); + + if (cpu == smp_processor_id() && &rq->cfs == cfs_rq) { + unsigned long max = rq->cpu_capacity_orig; + + /* + * There are a few boundary cases this might miss but it should + * get called often enough that that should (hopefully) not be + * a real problem -- added to that it only calls on the local + * CPU, so if we enqueue remotely we'll miss an update, but + * the next tick/schedule should update. + * + * It will not get called when we go idle, because the idle + * thread is a different class (!fair), nor will the utilization + * number include things like RT tasks. + * + * As is, the util number is not freq-invariant (we'd have to + * implement arch_scale_freq_capacity() for that). + * + * See cpu_util(). + */ + cpufreq_update_util(rq_clock(rq), + min(cfs_rq->avg.util_avg, max), max); + } +} + /* Group cfs_rq's load_avg is used for task_h_load and update_cfs_share */ -static inline int update_cfs_rq_load_avg(u64 now, struct cfs_rq *cfs_rq) +static inline int +update_cfs_rq_load_avg(u64 now, struct cfs_rq *cfs_rq, bool update_freq) { struct sched_avg *sa = &cfs_rq->avg; - int decayed, removed = 0; + int decayed, removed_load = 0, removed_util = 0; if (atomic_long_read(&cfs_rq->removed_load_avg)) { s64 r = atomic_long_xchg(&cfs_rq->removed_load_avg, 0); sa->load_avg = max_t(long, sa->load_avg - r, 0); sa->load_sum = max_t(s64, sa->load_sum - r * LOAD_AVG_MAX, 0); - removed = 1; + removed_load = 1; } if (atomic_long_read(&cfs_rq->removed_util_avg)) { long r = atomic_long_xchg(&cfs_rq->removed_util_avg, 0); sa->util_avg = max_t(long, sa->util_avg - r, 0); sa->util_sum = max_t(s32, sa->util_sum - r * LOAD_AVG_MAX, 0); + removed_util = 1; } decayed = __update_load_avg(now, cpu_of(rq_of(cfs_rq)), sa, @@ -2848,7 +2933,10 @@ static inline int update_cfs_rq_load_avg(u64 now, struct cfs_rq *cfs_rq) cfs_rq->load_last_update_time_copy = sa->last_update_time; #endif - return decayed || removed; + if (update_freq && (decayed || removed_util)) + cfs_rq_util_change(cfs_rq); + + return decayed || removed_load; } /* Update task and its cfs_rq load average */ @@ -2867,31 +2955,8 @@ static inline void update_load_avg(struct sched_entity *se, int update_tg) se->on_rq * scale_load_down(se->load.weight), cfs_rq->curr == se, NULL); - if (update_cfs_rq_load_avg(now, cfs_rq) && update_tg) + if (update_cfs_rq_load_avg(now, cfs_rq, true) && update_tg) update_tg_load_avg(cfs_rq, 0); - - if (cpu == smp_processor_id() && &rq->cfs == cfs_rq) { - unsigned long max = rq->cpu_capacity_orig; - - /* - * There are a few boundary cases this might miss but it should - * get called often enough that that should (hopefully) not be - * a real problem -- added to that it only calls on the local - * CPU, so if we enqueue remotely we'll miss an update, but - * the next tick/schedule should update. - * - * It will not get called when we go idle, because the idle - * thread is a different class (!fair), nor will the utilization - * number include things like RT tasks. - * - * As is, the util number is not freq-invariant (we'd have to - * implement arch_scale_freq_capacity() for that). - * - * See cpu_util(). - */ - cpufreq_update_util(rq_clock(rq), - min(cfs_rq->avg.util_avg, max), max); - } } static void attach_entity_load_avg(struct cfs_rq *cfs_rq, struct sched_entity *se) @@ -2919,6 +2984,8 @@ skip_aging: cfs_rq->avg.load_sum += se->avg.load_sum; cfs_rq->avg.util_avg += se->avg.util_avg; cfs_rq->avg.util_sum += se->avg.util_sum; + + cfs_rq_util_change(cfs_rq); } static void detach_entity_load_avg(struct cfs_rq *cfs_rq, struct sched_entity *se) @@ -2931,6 +2998,8 @@ static void detach_entity_load_avg(struct cfs_rq *cfs_rq, struct sched_entity *s cfs_rq->avg.load_sum = max_t(s64, cfs_rq->avg.load_sum - se->avg.load_sum, 0); cfs_rq->avg.util_avg = max_t(long, cfs_rq->avg.util_avg - se->avg.util_avg, 0); cfs_rq->avg.util_sum = max_t(s32, cfs_rq->avg.util_sum - se->avg.util_sum, 0); + + cfs_rq_util_change(cfs_rq); } /* Add the load generated by se into cfs_rq's load average */ @@ -2948,7 +3017,7 @@ enqueue_entity_load_avg(struct cfs_rq *cfs_rq, struct sched_entity *se) cfs_rq->curr == se, NULL); } - decayed = update_cfs_rq_load_avg(now, cfs_rq); + decayed = update_cfs_rq_load_avg(now, cfs_rq, !migrated); cfs_rq->runnable_load_avg += sa->load_avg; cfs_rq->runnable_load_sum += sa->load_sum; @@ -3030,7 +3099,14 @@ static int idle_balance(struct rq *this_rq); #else /* CONFIG_SMP */ -static inline void update_load_avg(struct sched_entity *se, int update_tg) {} +static inline void update_load_avg(struct sched_entity *se, int not_used) +{ + struct cfs_rq *cfs_rq = cfs_rq_of(se); + struct rq *rq = rq_of(cfs_rq); + + cpufreq_trigger_update(rq_clock(rq)); +} + static inline void enqueue_entity_load_avg(struct cfs_rq *cfs_rq, struct sched_entity *se) {} static inline void @@ -3178,10 +3254,41 @@ static inline void check_schedstat_required(void) #endif } + +/* + * MIGRATION + * + * dequeue + * update_curr() + * update_min_vruntime() + * vruntime -= min_vruntime + * + * enqueue + * update_curr() + * update_min_vruntime() + * vruntime += min_vruntime + * + * this way the vruntime transition between RQs is done when both + * min_vruntime are up-to-date. + * + * WAKEUP (remote) + * + * ->migrate_task_rq_fair() (p->state == TASK_WAKING) + * vruntime -= min_vruntime + * + * enqueue + * update_curr() + * update_min_vruntime() + * vruntime += min_vruntime + * + * this way we don't have the most up-to-date min_vruntime on the originating + * CPU and an up-to-date min_vruntime on the destination CPU. + */ + static void enqueue_entity(struct cfs_rq *cfs_rq, struct sched_entity *se, int flags) { - bool renorm = !(flags & ENQUEUE_WAKEUP) || (flags & ENQUEUE_WAKING); + bool renorm = !(flags & ENQUEUE_WAKEUP) || (flags & ENQUEUE_MIGRATED); bool curr = cfs_rq->curr == se; /* @@ -3195,7 +3302,9 @@ enqueue_entity(struct cfs_rq *cfs_rq, struct sched_entity *se, int flags) /* * Otherwise, renormalise after, such that we're placed at the current - * moment in time, instead of some random moment in the past. + * moment in time, instead of some random moment in the past. Being + * placed in the past could significantly boost this task to the + * fairness detriment of existing tasks. */ if (renorm && !curr) se->vruntime += cfs_rq->min_vruntime; @@ -4423,7 +4532,7 @@ static void dequeue_task_fair(struct rq *rq, struct task_struct *p, int flags) } #ifdef CONFIG_SMP - +#ifdef CONFIG_NO_HZ_COMMON /* * per rq 'load' arrray crap; XXX kill this. */ @@ -4489,13 +4598,13 @@ decay_load_missed(unsigned long load, unsigned long missed_updates, int idx) } return load; } +#endif /* CONFIG_NO_HZ_COMMON */ /** - * __update_cpu_load - update the rq->cpu_load[] statistics + * __cpu_load_update - update the rq->cpu_load[] statistics * @this_rq: The rq to update statistics for * @this_load: The current load * @pending_updates: The number of missed updates - * @active: !0 for NOHZ_FULL * * Update rq->cpu_load[] statistics. This function is usually called every * scheduler tick (TICK_NSEC). @@ -4524,12 +4633,12 @@ decay_load_missed(unsigned long load, unsigned long missed_updates, int idx) * load[i]_n = (1 - 1/2^i)^n * load[i]_0 * * see decay_load_misses(). For NOHZ_FULL we get to subtract and add the extra - * term. See the @active paramter. + * term. */ -static void __update_cpu_load(struct rq *this_rq, unsigned long this_load, - unsigned long pending_updates, int active) +static void cpu_load_update(struct rq *this_rq, unsigned long this_load, + unsigned long pending_updates) { - unsigned long tickless_load = active ? this_rq->cpu_load[0] : 0; + unsigned long __maybe_unused tickless_load = this_rq->cpu_load[0]; int i, scale; this_rq->nr_load_updates++; @@ -4542,6 +4651,7 @@ static void __update_cpu_load(struct rq *this_rq, unsigned long this_load, /* scale is effectively 1 << i now, and >> i divides by scale */ old_load = this_rq->cpu_load[i]; +#ifdef CONFIG_NO_HZ_COMMON old_load = decay_load_missed(old_load, pending_updates - 1, i); if (tickless_load) { old_load -= decay_load_missed(tickless_load, pending_updates - 1, i); @@ -4552,6 +4662,7 @@ static void __update_cpu_load(struct rq *this_rq, unsigned long this_load, */ old_load += tickless_load; } +#endif new_load = this_load; /* * Round up the averaging division if load is increasing. This @@ -4574,10 +4685,23 @@ static unsigned long weighted_cpuload(const int cpu) } #ifdef CONFIG_NO_HZ_COMMON -static void __update_cpu_load_nohz(struct rq *this_rq, - unsigned long curr_jiffies, - unsigned long load, - int active) +/* + * There is no sane way to deal with nohz on smp when using jiffies because the + * cpu doing the jiffies update might drift wrt the cpu doing the jiffy reading + * causing off-by-one errors in observed deltas; {0,2} instead of {1,1}. + * + * Therefore we need to avoid the delta approach from the regular tick when + * possible since that would seriously skew the load calculation. This is why we + * use cpu_load_update_periodic() for CPUs out of nohz. However we'll rely on + * jiffies deltas for updates happening while in nohz mode (idle ticks, idle + * loop exit, nohz_idle_balance, nohz full exit...) + * + * This means we might still be one tick off for nohz periods. + */ + +static void cpu_load_update_nohz(struct rq *this_rq, + unsigned long curr_jiffies, + unsigned long load) { unsigned long pending_updates; @@ -4589,28 +4713,15 @@ static void __update_cpu_load_nohz(struct rq *this_rq, * In the NOHZ_FULL case, we were non-idle, we should consider * its weighted load. */ - __update_cpu_load(this_rq, load, pending_updates, active); + cpu_load_update(this_rq, load, pending_updates); } } /* - * There is no sane way to deal with nohz on smp when using jiffies because the - * cpu doing the jiffies update might drift wrt the cpu doing the jiffy reading - * causing off-by-one errors in observed deltas; {0,2} instead of {1,1}. - * - * Therefore we cannot use the delta approach from the regular tick since that - * would seriously skew the load calculation. However we'll make do for those - * updates happening while idle (nohz_idle_balance) or coming out of idle - * (tick_nohz_idle_exit). - * - * This means we might still be one tick off for nohz periods. - */ - -/* * Called from nohz_idle_balance() to update the load ratings before doing the * idle balance. */ -static void update_cpu_load_idle(struct rq *this_rq) +static void cpu_load_update_idle(struct rq *this_rq) { /* * bail if there's load or we're actually up-to-date. @@ -4618,38 +4729,71 @@ static void update_cpu_load_idle(struct rq *this_rq) if (weighted_cpuload(cpu_of(this_rq))) return; - __update_cpu_load_nohz(this_rq, READ_ONCE(jiffies), 0, 0); + cpu_load_update_nohz(this_rq, READ_ONCE(jiffies), 0); } /* - * Called from tick_nohz_idle_exit() -- try and fix up the ticks we missed. + * Record CPU load on nohz entry so we know the tickless load to account + * on nohz exit. cpu_load[0] happens then to be updated more frequently + * than other cpu_load[idx] but it should be fine as cpu_load readers + * shouldn't rely into synchronized cpu_load[*] updates. */ -void update_cpu_load_nohz(int active) +void cpu_load_update_nohz_start(void) { struct rq *this_rq = this_rq(); + + /* + * This is all lockless but should be fine. If weighted_cpuload changes + * concurrently we'll exit nohz. And cpu_load write can race with + * cpu_load_update_idle() but both updater would be writing the same. + */ + this_rq->cpu_load[0] = weighted_cpuload(cpu_of(this_rq)); +} + +/* + * Account the tickless load in the end of a nohz frame. + */ +void cpu_load_update_nohz_stop(void) +{ unsigned long curr_jiffies = READ_ONCE(jiffies); - unsigned long load = active ? weighted_cpuload(cpu_of(this_rq)) : 0; + struct rq *this_rq = this_rq(); + unsigned long load; if (curr_jiffies == this_rq->last_load_update_tick) return; + load = weighted_cpuload(cpu_of(this_rq)); raw_spin_lock(&this_rq->lock); - __update_cpu_load_nohz(this_rq, curr_jiffies, load, active); + update_rq_clock(this_rq); + cpu_load_update_nohz(this_rq, curr_jiffies, load); raw_spin_unlock(&this_rq->lock); } -#endif /* CONFIG_NO_HZ */ +#else /* !CONFIG_NO_HZ_COMMON */ +static inline void cpu_load_update_nohz(struct rq *this_rq, + unsigned long curr_jiffies, + unsigned long load) { } +#endif /* CONFIG_NO_HZ_COMMON */ + +static void cpu_load_update_periodic(struct rq *this_rq, unsigned long load) +{ +#ifdef CONFIG_NO_HZ_COMMON + /* See the mess around cpu_load_update_nohz(). */ + this_rq->last_load_update_tick = READ_ONCE(jiffies); +#endif + cpu_load_update(this_rq, load, 1); +} /* * Called from scheduler_tick() */ -void update_cpu_load_active(struct rq *this_rq) +void cpu_load_update_active(struct rq *this_rq) { unsigned long load = weighted_cpuload(cpu_of(this_rq)); - /* - * See the mess around update_cpu_load_idle() / update_cpu_load_nohz(). - */ - this_rq->last_load_update_tick = jiffies; - __update_cpu_load(this_rq, load, 1, 1); + + if (tick_nohz_tick_stopped()) + cpu_load_update_nohz(this_rq, READ_ONCE(jiffies), load); + else + cpu_load_update_periodic(this_rq, load); } /* @@ -4707,46 +4851,6 @@ static unsigned long cpu_avg_load_per_task(int cpu) return 0; } -static void record_wakee(struct task_struct *p) -{ - /* - * Rough decay (wiping) for cost saving, don't worry - * about the boundary, really active task won't care - * about the loss. - */ - if (time_after(jiffies, current->wakee_flip_decay_ts + HZ)) { - current->wakee_flips >>= 1; - current->wakee_flip_decay_ts = jiffies; - } - - if (current->last_wakee != p) { - current->last_wakee = p; - current->wakee_flips++; - } -} - -static void task_waking_fair(struct task_struct *p) -{ - struct sched_entity *se = &p->se; - struct cfs_rq *cfs_rq = cfs_rq_of(se); - u64 min_vruntime; - -#ifndef CONFIG_64BIT - u64 min_vruntime_copy; - - do { - min_vruntime_copy = cfs_rq->min_vruntime_copy; - smp_rmb(); - min_vruntime = cfs_rq->min_vruntime; - } while (min_vruntime != min_vruntime_copy); -#else - min_vruntime = cfs_rq->min_vruntime; -#endif - - se->vruntime -= min_vruntime; - record_wakee(p); -} - #ifdef CONFIG_FAIR_GROUP_SCHED /* * effective_load() calculates the load change as seen from the root_task_group @@ -4862,17 +4966,39 @@ static long effective_load(struct task_group *tg, int cpu, long wl, long wg) #endif +static void record_wakee(struct task_struct *p) +{ + /* + * Only decay a single time; tasks that have less then 1 wakeup per + * jiffy will not have built up many flips. + */ + if (time_after(jiffies, current->wakee_flip_decay_ts + HZ)) { + current->wakee_flips >>= 1; + current->wakee_flip_decay_ts = jiffies; + } + + if (current->last_wakee != p) { + current->last_wakee = p; + current->wakee_flips++; + } +} + /* * Detect M:N waker/wakee relationships via a switching-frequency heuristic. + * * A waker of many should wake a different task than the one last awakened - * at a frequency roughly N times higher than one of its wakees. In order - * to determine whether we should let the load spread vs consolodating to - * shared cache, we look for a minimum 'flip' frequency of llc_size in one - * partner, and a factor of lls_size higher frequency in the other. With - * both conditions met, we can be relatively sure that the relationship is - * non-monogamous, with partner count exceeding socket size. Waker/wakee - * being client/server, worker/dispatcher, interrupt source or whatever is - * irrelevant, spread criteria is apparent partner count exceeds socket size. + * at a frequency roughly N times higher than one of its wakees. + * + * In order to determine whether we should let the load spread vs consolidating + * to shared cache, we look for a minimum 'flip' frequency of llc_size in one + * partner, and a factor of lls_size higher frequency in the other. + * + * With both conditions met, we can be relatively sure that the relationship is + * non-monogamous, with partner count exceeding socket size. + * + * Waker/wakee being client/server, worker/dispatcher, interrupt source or + * whatever is irrelevant, spread criteria is apparent partner count exceeds + * socket size. */ static int wake_wide(struct task_struct *p) { @@ -5177,8 +5303,10 @@ select_task_rq_fair(struct task_struct *p, int prev_cpu, int sd_flag, int wake_f int want_affine = 0; int sync = wake_flags & WF_SYNC; - if (sd_flag & SD_BALANCE_WAKE) + if (sd_flag & SD_BALANCE_WAKE) { + record_wakee(p); want_affine = !wake_wide(p) && cpumask_test_cpu(cpu, tsk_cpus_allowed(p)); + } rcu_read_lock(); for_each_domain(cpu, tmp) { @@ -5258,6 +5386,32 @@ select_task_rq_fair(struct task_struct *p, int prev_cpu, int sd_flag, int wake_f static void migrate_task_rq_fair(struct task_struct *p) { /* + * As blocked tasks retain absolute vruntime the migration needs to + * deal with this by subtracting the old and adding the new + * min_vruntime -- the latter is done by enqueue_entity() when placing + * the task on the new runqueue. + */ + if (p->state == TASK_WAKING) { + struct sched_entity *se = &p->se; + struct cfs_rq *cfs_rq = cfs_rq_of(se); + u64 min_vruntime; + +#ifndef CONFIG_64BIT + u64 min_vruntime_copy; + + do { + min_vruntime_copy = cfs_rq->min_vruntime_copy; + smp_rmb(); + min_vruntime = cfs_rq->min_vruntime; + } while (min_vruntime != min_vruntime_copy); +#else + min_vruntime = cfs_rq->min_vruntime; +#endif + + se->vruntime -= min_vruntime; + } + + /* * We are supposed to update the task to "current" time, then its up to date * and ready to go to new CPU/cfs_rq. But we have difficulty in getting * what current time is, so simply throw away the out-of-date time. This @@ -5440,7 +5594,7 @@ preempt: } static struct task_struct * -pick_next_task_fair(struct rq *rq, struct task_struct *prev) +pick_next_task_fair(struct rq *rq, struct task_struct *prev, struct pin_cookie cookie) { struct cfs_rq *cfs_rq = &rq->cfs; struct sched_entity *se; @@ -5553,9 +5707,9 @@ idle: * further scheduler activity on it and we're being very careful to * re-start the picking loop. */ - lockdep_unpin_lock(&rq->lock); + lockdep_unpin_lock(&rq->lock, cookie); new_tasks = idle_balance(rq); - lockdep_pin_lock(&rq->lock); + lockdep_repin_lock(&rq->lock, cookie); /* * Because idle_balance() releases (and re-acquires) rq->lock, it is * possible for any higher priority task to appear. In that case we @@ -5654,7 +5808,7 @@ static bool yield_to_task_fair(struct rq *rq, struct task_struct *p, bool preemp * W_i,0 = \Sum_j w_i,j (2) * * Where w_i,j is the weight of the j-th runnable task on cpu i. This weight - * is derived from the nice value as per prio_to_weight[]. + * is derived from the nice value as per sched_prio_to_weight[]. * * The weight average is an exponential decay average of the instantaneous * weight: @@ -6156,7 +6310,7 @@ static void update_blocked_averages(int cpu) if (throttled_hierarchy(cfs_rq)) continue; - if (update_cfs_rq_load_avg(cfs_rq_clock_task(cfs_rq), cfs_rq)) + if (update_cfs_rq_load_avg(cfs_rq_clock_task(cfs_rq), cfs_rq, true)) update_tg_load_avg(cfs_rq, 0); } raw_spin_unlock_irqrestore(&rq->lock, flags); @@ -6217,7 +6371,7 @@ static inline void update_blocked_averages(int cpu) raw_spin_lock_irqsave(&rq->lock, flags); update_rq_clock(rq); - update_cfs_rq_load_avg(cfs_rq_clock_task(cfs_rq), cfs_rq); + update_cfs_rq_load_avg(cfs_rq_clock_task(cfs_rq), cfs_rq, true); raw_spin_unlock_irqrestore(&rq->lock, flags); } @@ -6626,6 +6780,9 @@ static bool update_sd_pick_busiest(struct lb_env *env, if (!(env->sd->flags & SD_ASYM_PACKING)) return true; + /* No ASYM_PACKING if target cpu is already busy */ + if (env->idle == CPU_NOT_IDLE) + return true; /* * ASYM_PACKING needs to move all the work to the lowest * numbered CPUs in the group, therefore mark all groups @@ -6635,7 +6792,8 @@ static bool update_sd_pick_busiest(struct lb_env *env, if (!sds->busiest) return true; - if (group_first_cpu(sds->busiest) > group_first_cpu(sg)) + /* Prefer to move from highest possible cpu's work */ + if (group_first_cpu(sds->busiest) < group_first_cpu(sg)) return true; } @@ -6781,6 +6939,9 @@ static int check_asym_packing(struct lb_env *env, struct sd_lb_stats *sds) if (!(env->sd->flags & SD_ASYM_PACKING)) return 0; + if (env->idle == CPU_NOT_IDLE) + return 0; + if (!sds->busiest) return 0; @@ -6889,9 +7050,10 @@ static inline void calculate_imbalance(struct lb_env *env, struct sd_lb_stats *s } /* - * In the presence of smp nice balancing, certain scenarios can have - * max load less than avg load(as we skip the groups at or below - * its cpu_capacity, while calculating max_load..) + * Avg load of busiest sg can be less and avg load of local sg can + * be greater than avg load across all sgs of sd because avg load + * factors in sg capacity and sgs with smaller group_type are + * skipped when updating the busiest sg: */ if (busiest->avg_load <= sds->avg_load || local->avg_load >= sds->avg_load) { @@ -6904,11 +7066,12 @@ static inline void calculate_imbalance(struct lb_env *env, struct sd_lb_stats *s */ if (busiest->group_type == group_overloaded && local->group_type == group_overloaded) { - load_above_capacity = busiest->sum_nr_running * - SCHED_LOAD_SCALE; - if (load_above_capacity > busiest->group_capacity) + load_above_capacity = busiest->sum_nr_running * SCHED_CAPACITY_SCALE; + if (load_above_capacity > busiest->group_capacity) { load_above_capacity -= busiest->group_capacity; - else + load_above_capacity *= NICE_0_LOAD; + load_above_capacity /= busiest->group_capacity; + } else load_above_capacity = ~0UL; } @@ -6916,9 +7079,8 @@ static inline void calculate_imbalance(struct lb_env *env, struct sd_lb_stats *s * We're trying to get all the cpus to the average_load, so we don't * want to push ourselves above the average load, nor do we wish to * reduce the max loaded cpu below the average load. At the same time, - * we also don't want to reduce the group load below the group capacity - * (so that we can implement power-savings policies etc). Thus we look - * for the minimum possible imbalance. + * we also don't want to reduce the group load below the group + * capacity. Thus we look for the minimum possible imbalance. */ max_pull = min(busiest->avg_load - sds->avg_load, load_above_capacity); @@ -6942,10 +7104,7 @@ static inline void calculate_imbalance(struct lb_env *env, struct sd_lb_stats *s /** * find_busiest_group - Returns the busiest group within the sched_domain - * if there is an imbalance. If there isn't an imbalance, and - * the user has opted for power-savings, it returns a group whose - * CPUs can be put to idle by rebalancing those tasks elsewhere, if - * such a group exists. + * if there is an imbalance. * * Also calculates the amount of weighted load which should be moved * to restore balance. @@ -6953,9 +7112,6 @@ static inline void calculate_imbalance(struct lb_env *env, struct sd_lb_stats *s * @env: The load balancing environment. * * Return: - The busiest group if imbalance exists. - * - If no imbalance and user has opted for power-savings balance, - * return the least loaded group whose CPUs can be - * put to idle by rebalancing its tasks onto our group. */ static struct sched_group *find_busiest_group(struct lb_env *env) { @@ -6973,8 +7129,7 @@ static struct sched_group *find_busiest_group(struct lb_env *env) busiest = &sds.busiest_stat; /* ASYM feature bypasses nice load balance check */ - if ((env->idle == CPU_IDLE || env->idle == CPU_NEWLY_IDLE) && - check_asym_packing(env, &sds)) + if (check_asym_packing(env, &sds)) return sds.busiest; /* There is no busy sibling group to pull tasks from */ @@ -7399,10 +7554,7 @@ more_balance: &busiest->active_balance_work); } - /* - * We've kicked active balancing, reset the failure - * counter. - */ + /* We've kicked active balancing, force task migration. */ sd->nr_balance_failed = sd->cache_nice_tries+1; } } else @@ -7637,10 +7789,13 @@ static int active_load_balance_cpu_stop(void *data) schedstat_inc(sd, alb_count); p = detach_one_task(&env); - if (p) + if (p) { schedstat_inc(sd, alb_pushed); - else + /* Active balancing done, reset the failure counter. */ + sd->nr_balance_failed = 0; + } else { schedstat_inc(sd, alb_failed); + } } rcu_read_unlock(); out_unlock: @@ -7711,7 +7866,7 @@ static void nohz_balancer_kick(void) return; } -static inline void nohz_balance_exit_idle(int cpu) +void nohz_balance_exit_idle(unsigned int cpu) { if (unlikely(test_bit(NOHZ_TICK_STOPPED, nohz_flags(cpu)))) { /* @@ -7784,18 +7939,6 @@ void nohz_balance_enter_idle(int cpu) atomic_inc(&nohz.nr_cpus); set_bit(NOHZ_TICK_STOPPED, nohz_flags(cpu)); } - -static int sched_ilb_notifier(struct notifier_block *nfb, - unsigned long action, void *hcpu) -{ - switch (action & ~CPU_TASKS_FROZEN) { - case CPU_DYING: - nohz_balance_exit_idle(smp_processor_id()); - return NOTIFY_OK; - default: - return NOTIFY_DONE; - } -} #endif static DEFINE_SPINLOCK(balancing); @@ -7957,7 +8100,7 @@ static void nohz_idle_balance(struct rq *this_rq, enum cpu_idle_type idle) if (time_after_eq(jiffies, rq->next_balance)) { raw_spin_lock_irq(&rq->lock); update_rq_clock(rq); - update_cpu_load_idle(rq); + cpu_load_update_idle(rq); raw_spin_unlock_irq(&rq->lock); rebalance_domains(rq, CPU_IDLE); } @@ -8382,6 +8525,7 @@ int alloc_fair_sched_group(struct task_group *tg, struct task_group *parent) init_cfs_rq(cfs_rq); init_tg_cfs_entry(tg, cfs_rq, se, i, parent->se[i]); init_entity_runnable_average(se); + post_init_entity_util_avg(se); } return 1; @@ -8538,7 +8682,6 @@ const struct sched_class fair_sched_class = { .rq_online = rq_online_fair, .rq_offline = rq_offline_fair, - .task_waking = task_waking_fair, .task_dead = task_dead_fair, .set_cpus_allowed = set_cpus_allowed_common, #endif @@ -8600,7 +8743,6 @@ __init void init_sched_fair_class(void) #ifdef CONFIG_NO_HZ_COMMON nohz.next_balance = jiffies; zalloc_cpumask_var(&nohz.idle_cpus_mask, GFP_NOWAIT); - cpu_notifier(sched_ilb_notifier, 0); #endif #endif /* SMP */ diff --git a/kernel/sched/idle_task.c b/kernel/sched/idle_task.c index 47ce94931f1b..2ce5458bbe1d 100644 --- a/kernel/sched/idle_task.c +++ b/kernel/sched/idle_task.c @@ -24,7 +24,7 @@ static void check_preempt_curr_idle(struct rq *rq, struct task_struct *p, int fl } static struct task_struct * -pick_next_task_idle(struct rq *rq, struct task_struct *prev) +pick_next_task_idle(struct rq *rq, struct task_struct *prev, struct pin_cookie cookie) { put_prev_task(rq, prev); diff --git a/kernel/sched/loadavg.c b/kernel/sched/loadavg.c index ef7159012cf3..b0b93fd33af9 100644 --- a/kernel/sched/loadavg.c +++ b/kernel/sched/loadavg.c @@ -99,10 +99,13 @@ long calc_load_fold_active(struct rq *this_rq) static unsigned long calc_load(unsigned long load, unsigned long exp, unsigned long active) { - load *= exp; - load += active * (FIXED_1 - exp); - load += 1UL << (FSHIFT - 1); - return load >> FSHIFT; + unsigned long newload; + + newload = load * exp + active * (FIXED_1 - exp); + if (active >= load) + newload += FIXED_1-1; + + return newload / FIXED_1; } #ifdef CONFIG_NO_HZ_COMMON diff --git a/kernel/sched/rt.c b/kernel/sched/rt.c index c41ea7ac1764..d5690b722691 100644 --- a/kernel/sched/rt.c +++ b/kernel/sched/rt.c @@ -334,7 +334,7 @@ static void inc_rt_migration(struct sched_rt_entity *rt_se, struct rt_rq *rt_rq) rt_rq = &rq_of_rt_rq(rt_rq)->rt; rt_rq->rt_nr_total++; - if (p->nr_cpus_allowed > 1) + if (tsk_nr_cpus_allowed(p) > 1) rt_rq->rt_nr_migratory++; update_rt_migration(rt_rq); @@ -351,7 +351,7 @@ static void dec_rt_migration(struct sched_rt_entity *rt_se, struct rt_rq *rt_rq) rt_rq = &rq_of_rt_rq(rt_rq)->rt; rt_rq->rt_nr_total--; - if (p->nr_cpus_allowed > 1) + if (tsk_nr_cpus_allowed(p) > 1) rt_rq->rt_nr_migratory--; update_rt_migration(rt_rq); @@ -953,14 +953,14 @@ static void update_curr_rt(struct rq *rq) if (curr->sched_class != &rt_sched_class) return; - /* Kick cpufreq (see the comment in linux/cpufreq.h). */ - if (cpu_of(rq) == smp_processor_id()) - cpufreq_trigger_update(rq_clock(rq)); - delta_exec = rq_clock_task(rq) - curr->se.exec_start; if (unlikely((s64)delta_exec <= 0)) return; + /* Kick cpufreq (see the comment in linux/cpufreq.h). */ + if (cpu_of(rq) == smp_processor_id()) + cpufreq_trigger_update(rq_clock(rq)); + schedstat_set(curr->se.statistics.exec_max, max(curr->se.statistics.exec_max, delta_exec)); @@ -1324,7 +1324,7 @@ enqueue_task_rt(struct rq *rq, struct task_struct *p, int flags) enqueue_rt_entity(rt_se, flags); - if (!task_current(rq, p) && p->nr_cpus_allowed > 1) + if (!task_current(rq, p) && tsk_nr_cpus_allowed(p) > 1) enqueue_pushable_task(rq, p); } @@ -1413,7 +1413,7 @@ select_task_rq_rt(struct task_struct *p, int cpu, int sd_flag, int flags) * will have to sort it out. */ if (curr && unlikely(rt_task(curr)) && - (curr->nr_cpus_allowed < 2 || + (tsk_nr_cpus_allowed(curr) < 2 || curr->prio <= p->prio)) { int target = find_lowest_rq(p); @@ -1437,7 +1437,7 @@ static void check_preempt_equal_prio(struct rq *rq, struct task_struct *p) * Current can't be migrated, useless to reschedule, * let's hope p can move out. */ - if (rq->curr->nr_cpus_allowed == 1 || + if (tsk_nr_cpus_allowed(rq->curr) == 1 || !cpupri_find(&rq->rd->cpupri, rq->curr, NULL)) return; @@ -1445,7 +1445,7 @@ static void check_preempt_equal_prio(struct rq *rq, struct task_struct *p) * p is migratable, so let's not schedule it and * see if it is pushed or pulled somewhere else. */ - if (p->nr_cpus_allowed != 1 + if (tsk_nr_cpus_allowed(p) != 1 && cpupri_find(&rq->rd->cpupri, p, NULL)) return; @@ -1524,7 +1524,7 @@ static struct task_struct *_pick_next_task_rt(struct rq *rq) } static struct task_struct * -pick_next_task_rt(struct rq *rq, struct task_struct *prev) +pick_next_task_rt(struct rq *rq, struct task_struct *prev, struct pin_cookie cookie) { struct task_struct *p; struct rt_rq *rt_rq = &rq->rt; @@ -1536,9 +1536,9 @@ pick_next_task_rt(struct rq *rq, struct task_struct *prev) * disabled avoiding further scheduler activity on it and we're * being very careful to re-start the picking loop. */ - lockdep_unpin_lock(&rq->lock); + lockdep_unpin_lock(&rq->lock, cookie); pull_rt_task(rq); - lockdep_pin_lock(&rq->lock); + lockdep_repin_lock(&rq->lock, cookie); /* * pull_rt_task() can drop (and re-acquire) rq->lock; this * means a dl or stop task can slip in, in which case we need @@ -1579,7 +1579,7 @@ static void put_prev_task_rt(struct rq *rq, struct task_struct *p) * The previous task needs to be made eligible for pushing * if it is still active */ - if (on_rt_rq(&p->rt) && p->nr_cpus_allowed > 1) + if (on_rt_rq(&p->rt) && tsk_nr_cpus_allowed(p) > 1) enqueue_pushable_task(rq, p); } @@ -1629,7 +1629,7 @@ static int find_lowest_rq(struct task_struct *task) if (unlikely(!lowest_mask)) return -1; - if (task->nr_cpus_allowed == 1) + if (tsk_nr_cpus_allowed(task) == 1) return -1; /* No other targets possible */ if (!cpupri_find(&task_rq(task)->rd->cpupri, task, lowest_mask)) @@ -1729,6 +1729,7 @@ static struct rq *find_lock_lowest_rq(struct task_struct *task, struct rq *rq) !cpumask_test_cpu(lowest_rq->cpu, tsk_cpus_allowed(task)) || task_running(rq, task) || + !rt_task(task) || !task_on_rq_queued(task))) { double_unlock_balance(rq, lowest_rq); @@ -1761,7 +1762,7 @@ static struct task_struct *pick_next_pushable_task(struct rq *rq) BUG_ON(rq->cpu != task_cpu(p)); BUG_ON(task_current(rq, p)); - BUG_ON(p->nr_cpus_allowed <= 1); + BUG_ON(tsk_nr_cpus_allowed(p) <= 1); BUG_ON(!task_on_rq_queued(p)); BUG_ON(!rt_task(p)); @@ -2121,9 +2122,9 @@ static void task_woken_rt(struct rq *rq, struct task_struct *p) { if (!task_running(rq, p) && !test_tsk_need_resched(rq->curr) && - p->nr_cpus_allowed > 1 && + tsk_nr_cpus_allowed(p) > 1 && (dl_task(rq->curr) || rt_task(rq->curr)) && - (rq->curr->nr_cpus_allowed < 2 || + (tsk_nr_cpus_allowed(rq->curr) < 2 || rq->curr->prio <= p->prio)) push_rt_tasks(rq); } @@ -2196,7 +2197,7 @@ static void switched_to_rt(struct rq *rq, struct task_struct *p) */ if (task_on_rq_queued(p) && rq->curr != p) { #ifdef CONFIG_SMP - if (p->nr_cpus_allowed > 1 && rq->rt.overloaded) + if (tsk_nr_cpus_allowed(p) > 1 && rq->rt.overloaded) queue_push_tasks(rq); #else if (p->prio < rq->curr->prio) diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h index ec2e8d23527e..72f1f3087b04 100644 --- a/kernel/sched/sched.h +++ b/kernel/sched/sched.h @@ -31,9 +31,9 @@ extern void calc_global_load_tick(struct rq *this_rq); extern long calc_load_fold_active(struct rq *this_rq); #ifdef CONFIG_SMP -extern void update_cpu_load_active(struct rq *this_rq); +extern void cpu_load_update_active(struct rq *this_rq); #else -static inline void update_cpu_load_active(struct rq *this_rq) { } +static inline void cpu_load_update_active(struct rq *this_rq) { } #endif /* @@ -49,25 +49,32 @@ static inline void update_cpu_load_active(struct rq *this_rq) { } * and does not change the user-interface for setting shares/weights. * * We increase resolution only if we have enough bits to allow this increased - * resolution (i.e. BITS_PER_LONG > 32). The costs for increasing resolution - * when BITS_PER_LONG <= 32 are pretty high and the returns do not justify the - * increased costs. + * resolution (i.e. 64bit). The costs for increasing resolution when 32bit are + * pretty high and the returns do not justify the increased costs. + * + * Really only required when CONFIG_FAIR_GROUP_SCHED is also set, but to + * increase coverage and consistency always enable it on 64bit platforms. */ -#if 0 /* BITS_PER_LONG > 32 -- currently broken: it increases power usage under light load */ -# define SCHED_LOAD_RESOLUTION 10 -# define scale_load(w) ((w) << SCHED_LOAD_RESOLUTION) -# define scale_load_down(w) ((w) >> SCHED_LOAD_RESOLUTION) +#ifdef CONFIG_64BIT +# define NICE_0_LOAD_SHIFT (SCHED_FIXEDPOINT_SHIFT + SCHED_FIXEDPOINT_SHIFT) +# define scale_load(w) ((w) << SCHED_FIXEDPOINT_SHIFT) +# define scale_load_down(w) ((w) >> SCHED_FIXEDPOINT_SHIFT) #else -# define SCHED_LOAD_RESOLUTION 0 +# define NICE_0_LOAD_SHIFT (SCHED_FIXEDPOINT_SHIFT) # define scale_load(w) (w) # define scale_load_down(w) (w) #endif -#define SCHED_LOAD_SHIFT (10 + SCHED_LOAD_RESOLUTION) -#define SCHED_LOAD_SCALE (1L << SCHED_LOAD_SHIFT) - -#define NICE_0_LOAD SCHED_LOAD_SCALE -#define NICE_0_SHIFT SCHED_LOAD_SHIFT +/* + * Task weight (visible to users) and its load (invisible to users) have + * independent resolution, but they should be well calibrated. We use + * scale_load() and scale_load_down(w) to convert between them. The + * following must be true: + * + * scale_load(sched_prio_to_weight[USER_PRIO(NICE_TO_PRIO(0))]) == NICE_0_LOAD + * + */ +#define NICE_0_LOAD (1L << NICE_0_LOAD_SHIFT) /* * Single value that decides SCHED_DEADLINE internal math precision. @@ -585,11 +592,13 @@ struct rq { #endif #define CPU_LOAD_IDX_MAX 5 unsigned long cpu_load[CPU_LOAD_IDX_MAX]; - unsigned long last_load_update_tick; #ifdef CONFIG_NO_HZ_COMMON +#ifdef CONFIG_SMP + unsigned long last_load_update_tick; +#endif /* CONFIG_SMP */ u64 nohz_stamp; unsigned long nohz_flags; -#endif +#endif /* CONFIG_NO_HZ_COMMON */ #ifdef CONFIG_NO_HZ_FULL unsigned long last_sched_tick; #endif @@ -854,7 +863,7 @@ DECLARE_PER_CPU(struct sched_domain *, sd_asym); struct sched_group_capacity { atomic_t ref; /* - * CPU capacity of this group, SCHED_LOAD_SCALE being max capacity + * CPU capacity of this group, SCHED_CAPACITY_SCALE being max capacity * for a single CPU. */ unsigned int capacity; @@ -1159,7 +1168,7 @@ extern const u32 sched_prio_to_wmult[40]; * * ENQUEUE_HEAD - place at front of runqueue (tail if not specified) * ENQUEUE_REPLENISH - CBS (replenish runtime and postpone deadline) - * ENQUEUE_WAKING - sched_class::task_waking was called + * ENQUEUE_MIGRATED - the task was migrated during wakeup * */ @@ -1174,9 +1183,9 @@ extern const u32 sched_prio_to_wmult[40]; #define ENQUEUE_HEAD 0x08 #define ENQUEUE_REPLENISH 0x10 #ifdef CONFIG_SMP -#define ENQUEUE_WAKING 0x20 +#define ENQUEUE_MIGRATED 0x20 #else -#define ENQUEUE_WAKING 0x00 +#define ENQUEUE_MIGRATED 0x00 #endif #define RETRY_TASK ((void *)-1UL) @@ -1200,14 +1209,14 @@ struct sched_class { * tasks. */ struct task_struct * (*pick_next_task) (struct rq *rq, - struct task_struct *prev); + struct task_struct *prev, + struct pin_cookie cookie); void (*put_prev_task) (struct rq *rq, struct task_struct *p); #ifdef CONFIG_SMP int (*select_task_rq)(struct task_struct *p, int task_cpu, int sd_flag, int flags); void (*migrate_task_rq)(struct task_struct *p); - void (*task_waking) (struct task_struct *task); void (*task_woken) (struct rq *this_rq, struct task_struct *task); void (*set_cpus_allowed)(struct task_struct *p, @@ -1313,6 +1322,7 @@ extern void init_dl_task_timer(struct sched_dl_entity *dl_se); unsigned long to_ratio(u64 period, u64 runtime); extern void init_entity_runnable_average(struct sched_entity *se); +extern void post_init_entity_util_avg(struct sched_entity *se); #ifdef CONFIG_NO_HZ_FULL extern bool sched_can_stop_tick(struct rq *rq); @@ -1448,86 +1458,32 @@ static inline void sched_rt_avg_update(struct rq *rq, u64 rt_delta) { } static inline void sched_avg_update(struct rq *rq) { } #endif -/* - * __task_rq_lock - lock the rq @p resides on. - */ -static inline struct rq *__task_rq_lock(struct task_struct *p) - __acquires(rq->lock) -{ - struct rq *rq; - - lockdep_assert_held(&p->pi_lock); - - for (;;) { - rq = task_rq(p); - raw_spin_lock(&rq->lock); - if (likely(rq == task_rq(p) && !task_on_rq_migrating(p))) { - lockdep_pin_lock(&rq->lock); - return rq; - } - raw_spin_unlock(&rq->lock); - - while (unlikely(task_on_rq_migrating(p))) - cpu_relax(); - } -} +struct rq_flags { + unsigned long flags; + struct pin_cookie cookie; +}; -/* - * task_rq_lock - lock p->pi_lock and lock the rq @p resides on. - */ -static inline struct rq *task_rq_lock(struct task_struct *p, unsigned long *flags) +struct rq *__task_rq_lock(struct task_struct *p, struct rq_flags *rf) + __acquires(rq->lock); +struct rq *task_rq_lock(struct task_struct *p, struct rq_flags *rf) __acquires(p->pi_lock) - __acquires(rq->lock) -{ - struct rq *rq; - - for (;;) { - raw_spin_lock_irqsave(&p->pi_lock, *flags); - rq = task_rq(p); - raw_spin_lock(&rq->lock); - /* - * move_queued_task() task_rq_lock() - * - * ACQUIRE (rq->lock) - * [S] ->on_rq = MIGRATING [L] rq = task_rq() - * WMB (__set_task_cpu()) ACQUIRE (rq->lock); - * [S] ->cpu = new_cpu [L] task_rq() - * [L] ->on_rq - * RELEASE (rq->lock) - * - * If we observe the old cpu in task_rq_lock, the acquire of - * the old rq->lock will fully serialize against the stores. - * - * If we observe the new cpu in task_rq_lock, the acquire will - * pair with the WMB to ensure we must then also see migrating. - */ - if (likely(rq == task_rq(p) && !task_on_rq_migrating(p))) { - lockdep_pin_lock(&rq->lock); - return rq; - } - raw_spin_unlock(&rq->lock); - raw_spin_unlock_irqrestore(&p->pi_lock, *flags); + __acquires(rq->lock); - while (unlikely(task_on_rq_migrating(p))) - cpu_relax(); - } -} - -static inline void __task_rq_unlock(struct rq *rq) +static inline void __task_rq_unlock(struct rq *rq, struct rq_flags *rf) __releases(rq->lock) { - lockdep_unpin_lock(&rq->lock); + lockdep_unpin_lock(&rq->lock, rf->cookie); raw_spin_unlock(&rq->lock); } static inline void -task_rq_unlock(struct rq *rq, struct task_struct *p, unsigned long *flags) +task_rq_unlock(struct rq *rq, struct task_struct *p, struct rq_flags *rf) __releases(rq->lock) __releases(p->pi_lock) { - lockdep_unpin_lock(&rq->lock); + lockdep_unpin_lock(&rq->lock, rf->cookie); raw_spin_unlock(&rq->lock); - raw_spin_unlock_irqrestore(&p->pi_lock, *flags); + raw_spin_unlock_irqrestore(&p->pi_lock, rf->flags); } #ifdef CONFIG_SMP @@ -1743,6 +1699,10 @@ enum rq_nohz_flag_bits { }; #define nohz_flags(cpu) (&cpu_rq(cpu)->nohz_flags) + +extern void nohz_balance_exit_idle(unsigned int cpu); +#else +static inline void nohz_balance_exit_idle(unsigned int cpu) { } #endif #ifdef CONFIG_IRQ_TIME_ACCOUNTING @@ -1842,6 +1802,14 @@ static inline void cpufreq_update_util(u64 time, unsigned long util, unsigned lo static inline void cpufreq_trigger_update(u64 time) {} #endif /* CONFIG_CPU_FREQ */ +#ifdef arch_scale_freq_capacity +#ifndef arch_scale_freq_invariant +#define arch_scale_freq_invariant() (true) +#endif +#else /* arch_scale_freq_capacity */ +#define arch_scale_freq_invariant() (false) +#endif + static inline void account_reset_rq(struct rq *rq) { #ifdef CONFIG_IRQ_TIME_ACCOUNTING diff --git a/kernel/sched/stop_task.c b/kernel/sched/stop_task.c index cbc67da10954..604297a08b3a 100644 --- a/kernel/sched/stop_task.c +++ b/kernel/sched/stop_task.c @@ -24,7 +24,7 @@ check_preempt_curr_stop(struct rq *rq, struct task_struct *p, int flags) } static struct task_struct * -pick_next_task_stop(struct rq *rq, struct task_struct *prev) +pick_next_task_stop(struct rq *rq, struct task_struct *prev, struct pin_cookie cookie) { struct task_struct *stop = rq->stop; diff --git a/kernel/signal.c b/kernel/signal.c index aa9bf00749c1..ab122a2cee41 100644 --- a/kernel/signal.c +++ b/kernel/signal.c @@ -3099,12 +3099,14 @@ do_sigaltstack (const stack_t __user *uss, stack_t __user *uoss, unsigned long s oss.ss_sp = (void __user *) current->sas_ss_sp; oss.ss_size = current->sas_ss_size; - oss.ss_flags = sas_ss_flags(sp); + oss.ss_flags = sas_ss_flags(sp) | + (current->sas_ss_flags & SS_FLAG_BITS); if (uss) { void __user *ss_sp; size_t ss_size; - int ss_flags; + unsigned ss_flags; + int ss_mode; error = -EFAULT; if (!access_ok(VERIFY_READ, uss, sizeof(*uss))) @@ -3119,18 +3121,13 @@ do_sigaltstack (const stack_t __user *uss, stack_t __user *uoss, unsigned long s if (on_sig_stack(sp)) goto out; + ss_mode = ss_flags & ~SS_FLAG_BITS; error = -EINVAL; - /* - * Note - this code used to test ss_flags incorrectly: - * old code may have been written using ss_flags==0 - * to mean ss_flags==SS_ONSTACK (as this was the only - * way that worked) - this fix preserves that older - * mechanism. - */ - if (ss_flags != SS_DISABLE && ss_flags != SS_ONSTACK && ss_flags != 0) + if (ss_mode != SS_DISABLE && ss_mode != SS_ONSTACK && + ss_mode != 0) goto out; - if (ss_flags == SS_DISABLE) { + if (ss_mode == SS_DISABLE) { ss_size = 0; ss_sp = NULL; } else { @@ -3141,6 +3138,7 @@ do_sigaltstack (const stack_t __user *uss, stack_t __user *uoss, unsigned long s current->sas_ss_sp = (unsigned long) ss_sp; current->sas_ss_size = ss_size; + current->sas_ss_flags = ss_flags; } error = 0; @@ -3171,9 +3169,14 @@ int restore_altstack(const stack_t __user *uss) int __save_altstack(stack_t __user *uss, unsigned long sp) { struct task_struct *t = current; - return __put_user((void __user *)t->sas_ss_sp, &uss->ss_sp) | - __put_user(sas_ss_flags(sp), &uss->ss_flags) | + int err = __put_user((void __user *)t->sas_ss_sp, &uss->ss_sp) | + __put_user(t->sas_ss_flags, &uss->ss_flags) | __put_user(t->sas_ss_size, &uss->ss_size); + if (err) + return err; + if (t->sas_ss_flags & SS_AUTODISARM) + sas_ss_reset(t); + return 0; } #ifdef CONFIG_COMPAT diff --git a/kernel/sysctl.c b/kernel/sysctl.c index 725587f10667..c8b318663525 100644 --- a/kernel/sysctl.c +++ b/kernel/sysctl.c @@ -130,6 +130,9 @@ static int one_thousand = 1000; #ifdef CONFIG_PRINTK static int ten_thousand = 10000; #endif +#ifdef CONFIG_PERF_EVENTS +static int six_hundred_forty_kb = 640 * 1024; +#endif /* this is needed for the proc_doulongvec_minmax of vm_dirty_bytes */ static unsigned long dirty_bytes_min = 2 * PAGE_SIZE; @@ -1144,6 +1147,15 @@ static struct ctl_table kern_table[] = { .extra1 = &zero, .extra2 = &one_hundred, }, + { + .procname = "perf_event_max_stack", + .data = NULL, /* filled in by handler */ + .maxlen = sizeof(sysctl_perf_event_max_stack), + .mode = 0644, + .proc_handler = perf_event_max_stack_handler, + .extra1 = &zero, + .extra2 = &six_hundred_forty_kb, + }, #endif #ifdef CONFIG_KMEMCHECK { diff --git a/kernel/taskstats.c b/kernel/taskstats.c index 21f82c29c914..b3f05ee20d18 100644 --- a/kernel/taskstats.c +++ b/kernel/taskstats.c @@ -357,10 +357,6 @@ static int parse(struct nlattr *na, struct cpumask *mask) return ret; } -#if defined(CONFIG_64BIT) && !defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) -#define TASKSTATS_NEEDS_PADDING 1 -#endif - static struct taskstats *mk_reply(struct sk_buff *skb, int type, u32 pid) { struct nlattr *na, *ret; @@ -370,29 +366,6 @@ static struct taskstats *mk_reply(struct sk_buff *skb, int type, u32 pid) ? TASKSTATS_TYPE_AGGR_PID : TASKSTATS_TYPE_AGGR_TGID; - /* - * The taskstats structure is internally aligned on 8 byte - * boundaries but the layout of the aggregrate reply, with - * two NLA headers and the pid (each 4 bytes), actually - * force the entire structure to be unaligned. This causes - * the kernel to issue unaligned access warnings on some - * architectures like ia64. Unfortunately, some software out there - * doesn't properly unroll the NLA packet and assumes that the start - * of the taskstats structure will always be 20 bytes from the start - * of the netlink payload. Aligning the start of the taskstats - * structure breaks this software, which we don't want. So, for now - * the alignment only happens on architectures that require it - * and those users will have to update to fixed versions of those - * packages. Space is reserved in the packet only when needed. - * This ifdef should be removed in several years e.g. 2012 once - * we can be confident that fixed versions are installed on most - * systems. We add the padding before the aggregate since the - * aggregate is already a defined type. - */ -#ifdef TASKSTATS_NEEDS_PADDING - if (nla_put(skb, TASKSTATS_TYPE_NULL, 0, NULL) < 0) - goto err; -#endif na = nla_nest_start(skb, aggr); if (!na) goto err; @@ -401,7 +374,8 @@ static struct taskstats *mk_reply(struct sk_buff *skb, int type, u32 pid) nla_nest_cancel(skb, na); goto err; } - ret = nla_reserve(skb, TASKSTATS_TYPE_STATS, sizeof(struct taskstats)); + ret = nla_reserve_64bit(skb, TASKSTATS_TYPE_STATS, + sizeof(struct taskstats), TASKSTATS_TYPE_NULL); if (!ret) { nla_nest_cancel(skb, na); goto err; @@ -500,10 +474,9 @@ static size_t taskstats_packet_size(void) size_t size; size = nla_total_size(sizeof(u32)) + - nla_total_size(sizeof(struct taskstats)) + nla_total_size(0); -#ifdef TASKSTATS_NEEDS_PADDING - size += nla_total_size(0); /* Padding for alignment */ -#endif + nla_total_size_64bit(sizeof(struct taskstats)) + + nla_total_size(0); + return size; } diff --git a/kernel/time/tick-sched.c b/kernel/time/tick-sched.c index 58e3310c9b21..536ada80f6dd 100644 --- a/kernel/time/tick-sched.c +++ b/kernel/time/tick-sched.c @@ -262,7 +262,7 @@ static void tick_nohz_dep_set_all(atomic_t *dep, { int prev; - prev = atomic_fetch_or(dep, BIT(bit)); + prev = atomic_fetch_or(BIT(bit), dep); if (!prev) tick_nohz_full_kick_all(); } @@ -292,7 +292,7 @@ void tick_nohz_dep_set_cpu(int cpu, enum tick_dep_bits bit) ts = per_cpu_ptr(&tick_cpu_sched, cpu); - prev = atomic_fetch_or(&ts->tick_dep_mask, BIT(bit)); + prev = atomic_fetch_or(BIT(bit), &ts->tick_dep_mask); if (!prev) { preempt_disable(); /* Perf needs local kick that is NMI safe */ @@ -776,6 +776,7 @@ static ktime_t tick_nohz_stop_sched_tick(struct tick_sched *ts, if (!ts->tick_stopped) { nohz_balance_enter_idle(cpu); calc_load_enter_idle(); + cpu_load_update_nohz_start(); ts->last_tick = hrtimer_get_expires(&ts->sched_timer); ts->tick_stopped = 1; @@ -802,11 +803,11 @@ out: return tick; } -static void tick_nohz_restart_sched_tick(struct tick_sched *ts, ktime_t now, int active) +static void tick_nohz_restart_sched_tick(struct tick_sched *ts, ktime_t now) { /* Update jiffies first */ tick_do_update_jiffies64(now); - update_cpu_load_nohz(active); + cpu_load_update_nohz_stop(); calc_load_exit_idle(); touch_softlockup_watchdog_sched(); @@ -833,7 +834,7 @@ static void tick_nohz_full_update_tick(struct tick_sched *ts) if (can_stop_full_tick(ts)) tick_nohz_stop_sched_tick(ts, ktime_get(), cpu); else if (ts->tick_stopped) - tick_nohz_restart_sched_tick(ts, ktime_get(), 1); + tick_nohz_restart_sched_tick(ts, ktime_get()); #endif } @@ -1024,7 +1025,7 @@ void tick_nohz_idle_exit(void) tick_nohz_stop_idle(ts, now); if (ts->tick_stopped) { - tick_nohz_restart_sched_tick(ts, now, 0); + tick_nohz_restart_sched_tick(ts, now); tick_nohz_account_idle_ticks(ts); } diff --git a/kernel/time/time.c b/kernel/time/time.c index be115b020d27..a4064b612066 100644 --- a/kernel/time/time.c +++ b/kernel/time/time.c @@ -160,15 +160,15 @@ static inline void warp_clock(void) * various programs will get confused when the clock gets warped. */ -int do_sys_settimeofday(const struct timespec *tv, const struct timezone *tz) +int do_sys_settimeofday64(const struct timespec64 *tv, const struct timezone *tz) { static int firsttime = 1; int error = 0; - if (tv && !timespec_valid(tv)) + if (tv && !timespec64_valid(tv)) return -EINVAL; - error = security_settime(tv, tz); + error = security_settime64(tv, tz); if (error) return error; @@ -186,7 +186,7 @@ int do_sys_settimeofday(const struct timespec *tv, const struct timezone *tz) } } if (tv) - return do_settimeofday(tv); + return do_settimeofday64(tv); return 0; } diff --git a/kernel/torture.c b/kernel/torture.c index 44aa462d033f..fa0bdeee17ac 100644 --- a/kernel/torture.c +++ b/kernel/torture.c @@ -451,6 +451,7 @@ static int torture_shutdown(void *arg) torture_shutdown_hook(); else VERBOSE_TOROUT_STRING("No torture_shutdown_hook(), skipping."); + ftrace_dump(DUMP_ALL); kernel_power_off(); /* Shut down the system. */ return 0; } @@ -602,8 +603,9 @@ bool torture_init_begin(char *ttype, bool v, int *runnable) { mutex_lock(&fullstop_mutex); if (torture_type != NULL) { - pr_alert("torture_init_begin: refusing %s init: %s running", + pr_alert("torture_init_begin: Refusing %s init: %s running.\n", ttype, torture_type); + pr_alert("torture_init_begin: One torture test at a time!\n"); mutex_unlock(&fullstop_mutex); return false; } diff --git a/kernel/trace/Kconfig b/kernel/trace/Kconfig index e45db6b0d878..fafeaf803bd0 100644 --- a/kernel/trace/Kconfig +++ b/kernel/trace/Kconfig @@ -528,6 +528,32 @@ config MMIOTRACE See Documentation/trace/mmiotrace.txt. If you are not helping to develop drivers, say N. +config TRACING_MAP + bool + depends on ARCH_HAVE_NMI_SAFE_CMPXCHG + help + tracing_map is a special-purpose lock-free map for tracing, + separated out as a stand-alone facility in order to allow it + to be shared between multiple tracers. It isn't meant to be + generally used outside of that context, and is normally + selected by tracers that use it. + +config HIST_TRIGGERS + bool "Histogram triggers" + depends on ARCH_HAVE_NMI_SAFE_CMPXCHG + select TRACING_MAP + default n + help + Hist triggers allow one or more arbitrary trace event fields + to be aggregated into hash tables and dumped to stdout by + reading a debugfs/tracefs file. They're useful for + gathering quick and dirty (though precise) summaries of + event activity as an initial guide for further investigation + using more advanced tools. + + See Documentation/trace/events.txt. + If in doubt, say N. + config MMIOTRACE_TEST tristate "Test module for mmiotrace" depends on MMIOTRACE && m diff --git a/kernel/trace/Makefile b/kernel/trace/Makefile index 9b1044e936a6..979e7bfbde7a 100644 --- a/kernel/trace/Makefile +++ b/kernel/trace/Makefile @@ -31,6 +31,7 @@ obj-$(CONFIG_TRACING) += trace_output.o obj-$(CONFIG_TRACING) += trace_seq.o obj-$(CONFIG_TRACING) += trace_stat.o obj-$(CONFIG_TRACING) += trace_printk.o +obj-$(CONFIG_TRACING_MAP) += tracing_map.o obj-$(CONFIG_CONTEXT_SWITCH_TRACER) += trace_sched_switch.o obj-$(CONFIG_FUNCTION_TRACER) += trace_functions.o obj-$(CONFIG_IRQSOFF_TRACER) += trace_irqsoff.o @@ -53,6 +54,7 @@ obj-$(CONFIG_EVENT_TRACING) += trace_event_perf.o endif obj-$(CONFIG_EVENT_TRACING) += trace_events_filter.o obj-$(CONFIG_EVENT_TRACING) += trace_events_trigger.o +obj-$(CONFIG_HIST_TRIGGERS) += trace_events_hist.o obj-$(CONFIG_BPF_EVENTS) += bpf_trace.o obj-$(CONFIG_KPROBE_EVENT) += trace_kprobe.o obj-$(CONFIG_TRACEPOINTS) += power-traces.o diff --git a/kernel/trace/blktrace.c b/kernel/trace/blktrace.c index f94e7a21f52d..9aef8654e90d 100644 --- a/kernel/trace/blktrace.c +++ b/kernel/trace/blktrace.c @@ -1349,6 +1349,7 @@ static enum print_line_t print_one_line(struct trace_iterator *iter, if (t->action == BLK_TN_MESSAGE) { log_action(iter, long_act ? "message" : "m"); blk_log_msg(s, iter->ent); + return trace_handle_return(s); } if (unlikely(what == 0 || what >= ARRAY_SIZE(what2act))) @@ -1551,6 +1552,7 @@ static const struct { { BLK_TC_COMPLETE, "complete" }, { BLK_TC_FS, "fs" }, { BLK_TC_PC, "pc" }, + { BLK_TC_NOTIFY, "notify" }, { BLK_TC_AHEAD, "ahead" }, { BLK_TC_META, "meta" }, { BLK_TC_DISCARD, "discard" }, diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c index 3e4ffb3ace5f..780bcbe1d4de 100644 --- a/kernel/trace/bpf_trace.c +++ b/kernel/trace/bpf_trace.c @@ -62,17 +62,21 @@ EXPORT_SYMBOL_GPL(trace_call_bpf); static u64 bpf_probe_read(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5) { void *dst = (void *) (long) r1; - int size = (int) r2; + int ret, size = (int) r2; void *unsafe_ptr = (void *) (long) r3; - return probe_kernel_read(dst, unsafe_ptr, size); + ret = probe_kernel_read(dst, unsafe_ptr, size); + if (unlikely(ret < 0)) + memset(dst, 0, size); + + return ret; } static const struct bpf_func_proto bpf_probe_read_proto = { .func = bpf_probe_read, .gpl_only = true, .ret_type = RET_INTEGER, - .arg1_type = ARG_PTR_TO_STACK, + .arg1_type = ARG_PTR_TO_RAW_STACK, .arg2_type = ARG_CONST_STACK_SIZE, .arg3_type = ARG_ANYTHING, }; @@ -221,11 +225,12 @@ static const struct bpf_func_proto bpf_perf_event_read_proto = { .arg2_type = ARG_ANYTHING, }; -static u64 bpf_perf_event_output(u64 r1, u64 r2, u64 index, u64 r4, u64 size) +static u64 bpf_perf_event_output(u64 r1, u64 r2, u64 flags, u64 r4, u64 size) { struct pt_regs *regs = (struct pt_regs *) (long) r1; struct bpf_map *map = (struct bpf_map *) (long) r2; struct bpf_array *array = container_of(map, struct bpf_array, map); + u64 index = flags & BPF_F_INDEX_MASK; void *data = (void *) (long) r4; struct perf_sample_data sample_data; struct perf_event *event; @@ -235,6 +240,10 @@ static u64 bpf_perf_event_output(u64 r1, u64 r2, u64 index, u64 r4, u64 size) .data = data, }; + if (unlikely(flags & ~(BPF_F_INDEX_MASK))) + return -EINVAL; + if (index == BPF_F_CURRENT_CPU) + index = raw_smp_processor_id(); if (unlikely(index >= array->map.max_entries)) return -E2BIG; @@ -268,7 +277,34 @@ static const struct bpf_func_proto bpf_perf_event_output_proto = { .arg5_type = ARG_CONST_STACK_SIZE, }; -static const struct bpf_func_proto *kprobe_prog_func_proto(enum bpf_func_id func_id) +static DEFINE_PER_CPU(struct pt_regs, bpf_pt_regs); + +static u64 bpf_event_output(u64 r1, u64 r2, u64 flags, u64 r4, u64 size) +{ + struct pt_regs *regs = this_cpu_ptr(&bpf_pt_regs); + + perf_fetch_caller_regs(regs); + + return bpf_perf_event_output((long)regs, r2, flags, r4, size); +} + +static const struct bpf_func_proto bpf_event_output_proto = { + .func = bpf_event_output, + .gpl_only = true, + .ret_type = RET_INTEGER, + .arg1_type = ARG_PTR_TO_CTX, + .arg2_type = ARG_CONST_MAP_PTR, + .arg3_type = ARG_ANYTHING, + .arg4_type = ARG_PTR_TO_STACK, + .arg5_type = ARG_CONST_STACK_SIZE, +}; + +const struct bpf_func_proto *bpf_get_event_output_proto(void) +{ + return &bpf_event_output_proto; +} + +static const struct bpf_func_proto *tracing_func_proto(enum bpf_func_id func_id) { switch (func_id) { case BPF_FUNC_map_lookup_elem: @@ -295,12 +331,20 @@ static const struct bpf_func_proto *kprobe_prog_func_proto(enum bpf_func_id func return &bpf_get_smp_processor_id_proto; case BPF_FUNC_perf_event_read: return &bpf_perf_event_read_proto; + default: + return NULL; + } +} + +static const struct bpf_func_proto *kprobe_prog_func_proto(enum bpf_func_id func_id) +{ + switch (func_id) { case BPF_FUNC_perf_event_output: return &bpf_perf_event_output_proto; case BPF_FUNC_get_stackid: return &bpf_get_stackid_proto; default: - return NULL; + return tracing_func_proto(func_id); } } @@ -332,9 +376,82 @@ static struct bpf_prog_type_list kprobe_tl = { .type = BPF_PROG_TYPE_KPROBE, }; +static u64 bpf_perf_event_output_tp(u64 r1, u64 r2, u64 index, u64 r4, u64 size) +{ + /* + * r1 points to perf tracepoint buffer where first 8 bytes are hidden + * from bpf program and contain a pointer to 'struct pt_regs'. Fetch it + * from there and call the same bpf_perf_event_output() helper + */ + u64 ctx = *(long *)(uintptr_t)r1; + + return bpf_perf_event_output(ctx, r2, index, r4, size); +} + +static const struct bpf_func_proto bpf_perf_event_output_proto_tp = { + .func = bpf_perf_event_output_tp, + .gpl_only = true, + .ret_type = RET_INTEGER, + .arg1_type = ARG_PTR_TO_CTX, + .arg2_type = ARG_CONST_MAP_PTR, + .arg3_type = ARG_ANYTHING, + .arg4_type = ARG_PTR_TO_STACK, + .arg5_type = ARG_CONST_STACK_SIZE, +}; + +static u64 bpf_get_stackid_tp(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5) +{ + u64 ctx = *(long *)(uintptr_t)r1; + + return bpf_get_stackid(ctx, r2, r3, r4, r5); +} + +static const struct bpf_func_proto bpf_get_stackid_proto_tp = { + .func = bpf_get_stackid_tp, + .gpl_only = true, + .ret_type = RET_INTEGER, + .arg1_type = ARG_PTR_TO_CTX, + .arg2_type = ARG_CONST_MAP_PTR, + .arg3_type = ARG_ANYTHING, +}; + +static const struct bpf_func_proto *tp_prog_func_proto(enum bpf_func_id func_id) +{ + switch (func_id) { + case BPF_FUNC_perf_event_output: + return &bpf_perf_event_output_proto_tp; + case BPF_FUNC_get_stackid: + return &bpf_get_stackid_proto_tp; + default: + return tracing_func_proto(func_id); + } +} + +static bool tp_prog_is_valid_access(int off, int size, enum bpf_access_type type) +{ + if (off < sizeof(void *) || off >= PERF_MAX_TRACE_SIZE) + return false; + if (type != BPF_READ) + return false; + if (off % size != 0) + return false; + return true; +} + +static const struct bpf_verifier_ops tracepoint_prog_ops = { + .get_func_proto = tp_prog_func_proto, + .is_valid_access = tp_prog_is_valid_access, +}; + +static struct bpf_prog_type_list tracepoint_tl = { + .ops = &tracepoint_prog_ops, + .type = BPF_PROG_TYPE_TRACEPOINT, +}; + static int __init register_kprobe_prog_ops(void) { bpf_register_prog_type(&kprobe_tl); + bpf_register_prog_type(&tracepoint_tl); return 0; } late_initcall(register_kprobe_prog_ops); diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c index b1870fbd2b67..7e8d792da963 100644 --- a/kernel/trace/ftrace.c +++ b/kernel/trace/ftrace.c @@ -1530,7 +1530,19 @@ static int ftrace_cmp_recs(const void *a, const void *b) return 0; } -static unsigned long ftrace_location_range(unsigned long start, unsigned long end) +/** + * ftrace_location_range - return the first address of a traced location + * if it touches the given ip range + * @start: start of range to search. + * @end: end of range to search (inclusive). @end points to the last byte + * to check. + * + * Returns rec->ip if the related ftrace location is a least partly within + * the given address range. That is, the first address of the instruction + * that is either a NOP or call to the function tracer. It checks the ftrace + * internal tables to determine if the address belongs or not. + */ +unsigned long ftrace_location_range(unsigned long start, unsigned long end) { struct ftrace_page *pg; struct dyn_ftrace *rec; diff --git a/kernel/trace/power-traces.c b/kernel/trace/power-traces.c index 81b87451c0ea..0c7dee221dca 100644 --- a/kernel/trace/power-traces.c +++ b/kernel/trace/power-traces.c @@ -15,5 +15,6 @@ EXPORT_TRACEPOINT_SYMBOL_GPL(suspend_resume); EXPORT_TRACEPOINT_SYMBOL_GPL(cpu_idle); +EXPORT_TRACEPOINT_SYMBOL_GPL(cpu_frequency); EXPORT_TRACEPOINT_SYMBOL_GPL(powernv_throttle); diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c index 95181e36891a..9c143739b8d7 100644 --- a/kernel/trace/ring_buffer.c +++ b/kernel/trace/ring_buffer.c @@ -437,7 +437,7 @@ struct ring_buffer_per_cpu { raw_spinlock_t reader_lock; /* serialize readers */ arch_spinlock_t lock; struct lock_class_key lock_key; - unsigned int nr_pages; + unsigned long nr_pages; unsigned int current_context; struct list_head *pages; struct buffer_page *head_page; /* read from head */ @@ -458,7 +458,7 @@ struct ring_buffer_per_cpu { u64 write_stamp; u64 read_stamp; /* ring buffer pages to update, > 0 to add, < 0 to remove */ - int nr_pages_to_update; + long nr_pages_to_update; struct list_head new_pages; /* new pages to add */ struct work_struct update_pages_work; struct completion update_done; @@ -1128,10 +1128,10 @@ static int rb_check_pages(struct ring_buffer_per_cpu *cpu_buffer) return 0; } -static int __rb_allocate_pages(int nr_pages, struct list_head *pages, int cpu) +static int __rb_allocate_pages(long nr_pages, struct list_head *pages, int cpu) { - int i; struct buffer_page *bpage, *tmp; + long i; for (i = 0; i < nr_pages; i++) { struct page *page; @@ -1168,7 +1168,7 @@ free_pages: } static int rb_allocate_pages(struct ring_buffer_per_cpu *cpu_buffer, - unsigned nr_pages) + unsigned long nr_pages) { LIST_HEAD(pages); @@ -1193,7 +1193,7 @@ static int rb_allocate_pages(struct ring_buffer_per_cpu *cpu_buffer, } static struct ring_buffer_per_cpu * -rb_allocate_cpu_buffer(struct ring_buffer *buffer, int nr_pages, int cpu) +rb_allocate_cpu_buffer(struct ring_buffer *buffer, long nr_pages, int cpu) { struct ring_buffer_per_cpu *cpu_buffer; struct buffer_page *bpage; @@ -1293,8 +1293,9 @@ struct ring_buffer *__ring_buffer_alloc(unsigned long size, unsigned flags, struct lock_class_key *key) { struct ring_buffer *buffer; + long nr_pages; int bsize; - int cpu, nr_pages; + int cpu; /* keep it in its own cache line */ buffer = kzalloc(ALIGN(sizeof(*buffer), cache_line_size()), @@ -1420,12 +1421,12 @@ static inline unsigned long rb_page_write(struct buffer_page *bpage) } static int -rb_remove_pages(struct ring_buffer_per_cpu *cpu_buffer, unsigned int nr_pages) +rb_remove_pages(struct ring_buffer_per_cpu *cpu_buffer, unsigned long nr_pages) { struct list_head *tail_page, *to_remove, *next_page; struct buffer_page *to_remove_page, *tmp_iter_page; struct buffer_page *last_page, *first_page; - unsigned int nr_removed; + unsigned long nr_removed; unsigned long head_bit; int page_entries; @@ -1642,7 +1643,7 @@ int ring_buffer_resize(struct ring_buffer *buffer, unsigned long size, int cpu_id) { struct ring_buffer_per_cpu *cpu_buffer; - unsigned nr_pages; + unsigned long nr_pages; int cpu, err = 0; /* @@ -1656,14 +1657,13 @@ int ring_buffer_resize(struct ring_buffer *buffer, unsigned long size, !cpumask_test_cpu(cpu_id, buffer->cpumask)) return size; - size = DIV_ROUND_UP(size, BUF_PAGE_SIZE); - size *= BUF_PAGE_SIZE; + nr_pages = DIV_ROUND_UP(size, BUF_PAGE_SIZE); /* we need a minimum of two pages */ - if (size < BUF_PAGE_SIZE * 2) - size = BUF_PAGE_SIZE * 2; + if (nr_pages < 2) + nr_pages = 2; - nr_pages = DIV_ROUND_UP(size, BUF_PAGE_SIZE); + size = nr_pages * BUF_PAGE_SIZE; /* * Don't succeed if resizing is disabled, as a reader might be @@ -4640,8 +4640,9 @@ static int rb_cpu_notify(struct notifier_block *self, struct ring_buffer *buffer = container_of(self, struct ring_buffer, cpu_notify); long cpu = (long)hcpu; - int cpu_i, nr_pages_same; - unsigned int nr_pages; + long nr_pages_same; + int cpu_i; + unsigned long nr_pages; switch (action) { case CPU_UP_PREPARE: diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index a2f0b9f33e9b..8a4bd6b68a0b 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -253,6 +253,9 @@ unsigned long long ns2usecs(cycle_t nsec) #define TOP_LEVEL_TRACE_FLAGS (TRACE_ITER_PRINTK | \ TRACE_ITER_PRINTK_MSGONLY | TRACE_ITER_RECORD_CMD) +/* trace_flags that are default zero for instances */ +#define ZEROED_TRACE_FLAGS \ + TRACE_ITER_EVENT_FORK /* * The global_trace is the descriptor that holds the tracing @@ -303,33 +306,18 @@ void trace_array_put(struct trace_array *this_tr) mutex_unlock(&trace_types_lock); } -int filter_check_discard(struct trace_event_file *file, void *rec, - struct ring_buffer *buffer, - struct ring_buffer_event *event) -{ - if (unlikely(file->flags & EVENT_FILE_FL_FILTERED) && - !filter_match_preds(file->filter, rec)) { - ring_buffer_discard_commit(buffer, event); - return 1; - } - - return 0; -} -EXPORT_SYMBOL_GPL(filter_check_discard); - int call_filter_check_discard(struct trace_event_call *call, void *rec, struct ring_buffer *buffer, struct ring_buffer_event *event) { if (unlikely(call->flags & TRACE_EVENT_FL_FILTERED) && !filter_match_preds(call->filter, rec)) { - ring_buffer_discard_commit(buffer, event); + __trace_event_discard_commit(buffer, event); return 1; } return 0; } -EXPORT_SYMBOL_GPL(call_filter_check_discard); static cycle_t buffer_ftrace_now(struct trace_buffer *buf, int cpu) { @@ -1672,6 +1660,16 @@ tracing_generic_entry_update(struct trace_entry *entry, unsigned long flags, } EXPORT_SYMBOL_GPL(tracing_generic_entry_update); +static __always_inline void +trace_event_setup(struct ring_buffer_event *event, + int type, unsigned long flags, int pc) +{ + struct trace_entry *ent = ring_buffer_event_data(event); + + tracing_generic_entry_update(ent, flags, pc); + ent->type = type; +} + struct ring_buffer_event * trace_buffer_lock_reserve(struct ring_buffer *buffer, int type, @@ -1681,34 +1679,137 @@ trace_buffer_lock_reserve(struct ring_buffer *buffer, struct ring_buffer_event *event; event = ring_buffer_lock_reserve(buffer, len); - if (event != NULL) { - struct trace_entry *ent = ring_buffer_event_data(event); + if (event != NULL) + trace_event_setup(event, type, flags, pc); + + return event; +} + +DEFINE_PER_CPU(struct ring_buffer_event *, trace_buffered_event); +DEFINE_PER_CPU(int, trace_buffered_event_cnt); +static int trace_buffered_event_ref; + +/** + * trace_buffered_event_enable - enable buffering events + * + * When events are being filtered, it is quicker to use a temporary + * buffer to write the event data into if there's a likely chance + * that it will not be committed. The discard of the ring buffer + * is not as fast as committing, and is much slower than copying + * a commit. + * + * When an event is to be filtered, allocate per cpu buffers to + * write the event data into, and if the event is filtered and discarded + * it is simply dropped, otherwise, the entire data is to be committed + * in one shot. + */ +void trace_buffered_event_enable(void) +{ + struct ring_buffer_event *event; + struct page *page; + int cpu; - tracing_generic_entry_update(ent, flags, pc); - ent->type = type; + WARN_ON_ONCE(!mutex_is_locked(&event_mutex)); + + if (trace_buffered_event_ref++) + return; + + for_each_tracing_cpu(cpu) { + page = alloc_pages_node(cpu_to_node(cpu), + GFP_KERNEL | __GFP_NORETRY, 0); + if (!page) + goto failed; + + event = page_address(page); + memset(event, 0, sizeof(*event)); + + per_cpu(trace_buffered_event, cpu) = event; + + preempt_disable(); + if (cpu == smp_processor_id() && + this_cpu_read(trace_buffered_event) != + per_cpu(trace_buffered_event, cpu)) + WARN_ON_ONCE(1); + preempt_enable(); } - return event; + return; + failed: + trace_buffered_event_disable(); } -void -__buffer_unlock_commit(struct ring_buffer *buffer, struct ring_buffer_event *event) +static void enable_trace_buffered_event(void *data) { - __this_cpu_write(trace_cmdline_save, true); - ring_buffer_unlock_commit(buffer, event); + /* Probably not needed, but do it anyway */ + smp_rmb(); + this_cpu_dec(trace_buffered_event_cnt); } -void trace_buffer_unlock_commit(struct trace_array *tr, - struct ring_buffer *buffer, - struct ring_buffer_event *event, - unsigned long flags, int pc) +static void disable_trace_buffered_event(void *data) { - __buffer_unlock_commit(buffer, event); + this_cpu_inc(trace_buffered_event_cnt); +} - ftrace_trace_stack(tr, buffer, flags, 6, pc, NULL); - ftrace_trace_userstack(buffer, flags, pc); +/** + * trace_buffered_event_disable - disable buffering events + * + * When a filter is removed, it is faster to not use the buffered + * events, and to commit directly into the ring buffer. Free up + * the temp buffers when there are no more users. This requires + * special synchronization with current events. + */ +void trace_buffered_event_disable(void) +{ + int cpu; + + WARN_ON_ONCE(!mutex_is_locked(&event_mutex)); + + if (WARN_ON_ONCE(!trace_buffered_event_ref)) + return; + + if (--trace_buffered_event_ref) + return; + + preempt_disable(); + /* For each CPU, set the buffer as used. */ + smp_call_function_many(tracing_buffer_mask, + disable_trace_buffered_event, NULL, 1); + preempt_enable(); + + /* Wait for all current users to finish */ + synchronize_sched(); + + for_each_tracing_cpu(cpu) { + free_page((unsigned long)per_cpu(trace_buffered_event, cpu)); + per_cpu(trace_buffered_event, cpu) = NULL; + } + /* + * Make sure trace_buffered_event is NULL before clearing + * trace_buffered_event_cnt. + */ + smp_wmb(); + + preempt_disable(); + /* Do the work on each cpu */ + smp_call_function_many(tracing_buffer_mask, + enable_trace_buffered_event, NULL, 1); + preempt_enable(); +} + +void +__buffer_unlock_commit(struct ring_buffer *buffer, struct ring_buffer_event *event) +{ + __this_cpu_write(trace_cmdline_save, true); + + /* If this is the temp buffer, we need to commit fully */ + if (this_cpu_read(trace_buffered_event) == event) { + /* Length is in event->array[0] */ + ring_buffer_write(buffer, event->array[0], &event->array[1]); + /* Release the temp buffer */ + this_cpu_dec(trace_buffered_event_cnt); + } else + ring_buffer_unlock_commit(buffer, event); } -EXPORT_SYMBOL_GPL(trace_buffer_unlock_commit); static struct ring_buffer *temp_buffer; @@ -1719,8 +1820,23 @@ trace_event_buffer_lock_reserve(struct ring_buffer **current_rb, unsigned long flags, int pc) { struct ring_buffer_event *entry; + int val; *current_rb = trace_file->tr->trace_buffer.buffer; + + if ((trace_file->flags & + (EVENT_FILE_FL_SOFT_DISABLED | EVENT_FILE_FL_FILTERED)) && + (entry = this_cpu_read(trace_buffered_event))) { + /* Try to use the per cpu buffer first */ + val = this_cpu_inc_return(trace_buffered_event_cnt); + if (val == 1) { + trace_event_setup(entry, type, flags, pc); + entry->array[0] = len; + return entry; + } + this_cpu_dec(trace_buffered_event_cnt); + } + entry = trace_buffer_lock_reserve(*current_rb, type, len, flags, pc); /* @@ -1738,17 +1854,6 @@ trace_event_buffer_lock_reserve(struct ring_buffer **current_rb, } EXPORT_SYMBOL_GPL(trace_event_buffer_lock_reserve); -struct ring_buffer_event * -trace_current_buffer_lock_reserve(struct ring_buffer **current_rb, - int type, unsigned long len, - unsigned long flags, int pc) -{ - *current_rb = global_trace.trace_buffer.buffer; - return trace_buffer_lock_reserve(*current_rb, - type, len, flags, pc); -} -EXPORT_SYMBOL_GPL(trace_current_buffer_lock_reserve); - void trace_buffer_unlock_commit_regs(struct trace_array *tr, struct ring_buffer *buffer, struct ring_buffer_event *event, @@ -1760,14 +1865,6 @@ void trace_buffer_unlock_commit_regs(struct trace_array *tr, ftrace_trace_stack(tr, buffer, flags, 0, pc, regs); ftrace_trace_userstack(buffer, flags, pc); } -EXPORT_SYMBOL_GPL(trace_buffer_unlock_commit_regs); - -void trace_current_buffer_discard_commit(struct ring_buffer *buffer, - struct ring_buffer_event *event) -{ - ring_buffer_discard_commit(buffer, event); -} -EXPORT_SYMBOL_GPL(trace_current_buffer_discard_commit); void trace_function(struct trace_array *tr, @@ -3571,6 +3668,9 @@ int set_tracer_flag(struct trace_array *tr, unsigned int mask, int enabled) if (mask == TRACE_ITER_RECORD_CMD) trace_event_enable_cmd_record(enabled); + if (mask == TRACE_ITER_EVENT_FORK) + trace_event_follow_fork(tr, enabled); + if (mask == TRACE_ITER_OVERWRITE) { ring_buffer_change_overwrite(tr->trace_buffer.buffer, enabled); #ifdef CONFIG_TRACER_MAX_TRACE @@ -3658,7 +3758,7 @@ tracing_trace_options_write(struct file *filp, const char __user *ubuf, if (cnt >= sizeof(buf)) return -EINVAL; - if (copy_from_user(&buf, ubuf, cnt)) + if (copy_from_user(buf, ubuf, cnt)) return -EFAULT; buf[cnt] = 0; @@ -3804,12 +3904,19 @@ static const char readme_msg[] = "\t trigger: traceon, traceoff\n" "\t enable_event:<system>:<event>\n" "\t disable_event:<system>:<event>\n" +#ifdef CONFIG_HIST_TRIGGERS + "\t enable_hist:<system>:<event>\n" + "\t disable_hist:<system>:<event>\n" +#endif #ifdef CONFIG_STACKTRACE "\t\t stacktrace\n" #endif #ifdef CONFIG_TRACER_SNAPSHOT "\t\t snapshot\n" #endif +#ifdef CONFIG_HIST_TRIGGERS + "\t\t hist (see below)\n" +#endif "\t example: echo traceoff > events/block/block_unplug/trigger\n" "\t echo traceoff:3 > events/block/block_unplug/trigger\n" "\t echo 'enable_event:kmem:kmalloc:3 if nr_rq > 1' > \\\n" @@ -3825,6 +3932,56 @@ static const char readme_msg[] = "\t To remove a trigger with a count:\n" "\t echo '!<trigger>:0 > <system>/<event>/trigger\n" "\t Filters can be ignored when removing a trigger.\n" +#ifdef CONFIG_HIST_TRIGGERS + " hist trigger\t- If set, event hits are aggregated into a hash table\n" + "\t Format: hist:keys=<field1[,field2,...]>\n" + "\t [:values=<field1[,field2,...]>]\n" + "\t [:sort=<field1[,field2,...]>]\n" + "\t [:size=#entries]\n" + "\t [:pause][:continue][:clear]\n" + "\t [:name=histname1]\n" + "\t [if <filter>]\n\n" + "\t When a matching event is hit, an entry is added to a hash\n" + "\t table using the key(s) and value(s) named, and the value of a\n" + "\t sum called 'hitcount' is incremented. Keys and values\n" + "\t correspond to fields in the event's format description. Keys\n" + "\t can be any field, or the special string 'stacktrace'.\n" + "\t Compound keys consisting of up to two fields can be specified\n" + "\t by the 'keys' keyword. Values must correspond to numeric\n" + "\t fields. Sort keys consisting of up to two fields can be\n" + "\t specified using the 'sort' keyword. The sort direction can\n" + "\t be modified by appending '.descending' or '.ascending' to a\n" + "\t sort field. The 'size' parameter can be used to specify more\n" + "\t or fewer than the default 2048 entries for the hashtable size.\n" + "\t If a hist trigger is given a name using the 'name' parameter,\n" + "\t its histogram data will be shared with other triggers of the\n" + "\t same name, and trigger hits will update this common data.\n\n" + "\t Reading the 'hist' file for the event will dump the hash\n" + "\t table in its entirety to stdout. If there are multiple hist\n" + "\t triggers attached to an event, there will be a table for each\n" + "\t trigger in the output. The table displayed for a named\n" + "\t trigger will be the same as any other instance having the\n" + "\t same name. The default format used to display a given field\n" + "\t can be modified by appending any of the following modifiers\n" + "\t to the field name, as applicable:\n\n" + "\t .hex display a number as a hex value\n" + "\t .sym display an address as a symbol\n" + "\t .sym-offset display an address as a symbol and offset\n" + "\t .execname display a common_pid as a program name\n" + "\t .syscall display a syscall id as a syscall name\n\n" + "\t .log2 display log2 value rather than raw number\n\n" + "\t The 'pause' parameter can be used to pause an existing hist\n" + "\t trigger or to start a hist trigger but not log any events\n" + "\t until told to do so. 'continue' can be used to start or\n" + "\t restart a paused hist trigger.\n\n" + "\t The 'clear' parameter will clear the contents of a running\n" + "\t hist trigger and leave its current paused/active state\n" + "\t unchanged.\n\n" + "\t The enable_hist and disable_hist triggers can be used to\n" + "\t have one event conditionally start and stop another event's\n" + "\t already-attached hist trigger. The syntax is analagous to\n" + "\t the enable_event and disable_event triggers.\n" +#endif ; static ssize_t @@ -4474,7 +4631,7 @@ tracing_set_trace_write(struct file *filp, const char __user *ubuf, if (cnt > MAX_TRACER_SIZE) cnt = MAX_TRACER_SIZE; - if (copy_from_user(&buf, ubuf, cnt)) + if (copy_from_user(buf, ubuf, cnt)) return -EFAULT; buf[cnt] = 0; @@ -5264,7 +5421,7 @@ static ssize_t tracing_clock_write(struct file *filp, const char __user *ubuf, if (cnt >= sizeof(buf)) return -EINVAL; - if (copy_from_user(&buf, ubuf, cnt)) + if (copy_from_user(buf, ubuf, cnt)) return -EFAULT; buf[cnt] = 0; @@ -6650,7 +6807,7 @@ static int instance_mkdir(const char *name) if (!alloc_cpumask_var(&tr->tracing_cpumask, GFP_KERNEL)) goto out_free_tr; - tr->trace_flags = global_trace.trace_flags; + tr->trace_flags = global_trace.trace_flags & ~ZEROED_TRACE_FLAGS; cpumask_copy(tr->tracing_cpumask, cpu_all_mask); @@ -6724,6 +6881,12 @@ static int instance_rmdir(const char *name) list_del(&tr->list); + /* Disable all the flags that were enabled coming in */ + for (i = 0; i < TRACE_FLAGS_MAX_SIZE; i++) { + if ((1 << i) & ZEROED_TRACE_FLAGS) + set_tracer_flag(tr, 1 << i, 0); + } + tracing_set_nop(tr); event_trace_del_tracer(tr); ftrace_destroy_function_files(tr); diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h index 3fff4adfd431..5167c366d6b7 100644 --- a/kernel/trace/trace.h +++ b/kernel/trace/trace.h @@ -177,9 +177,8 @@ struct trace_options { }; struct trace_pid_list { - unsigned int nr_pids; - int order; - pid_t *pids; + int pid_max; + unsigned long *pids; }; /* @@ -656,6 +655,7 @@ static inline void __trace_stack(struct trace_array *tr, unsigned long flags, extern cycle_t ftrace_now(int cpu); extern void trace_find_cmdline(int pid, char comm[]); +extern void trace_event_follow_fork(struct trace_array *tr, bool enable); #ifdef CONFIG_DYNAMIC_FTRACE extern unsigned long ftrace_update_tot_cnt; @@ -967,6 +967,7 @@ extern int trace_get_user(struct trace_parser *parser, const char __user *ubuf, C(STOP_ON_FREE, "disable_on_free"), \ C(IRQ_INFO, "irq-info"), \ C(MARKERS, "markers"), \ + C(EVENT_FORK, "event-fork"), \ FUNCTION_FLAGS \ FGRAPH_FLAGS \ STACK_FLAGS \ @@ -1064,6 +1065,137 @@ struct trace_subsystem_dir { int nr_events; }; +extern int call_filter_check_discard(struct trace_event_call *call, void *rec, + struct ring_buffer *buffer, + struct ring_buffer_event *event); + +void trace_buffer_unlock_commit_regs(struct trace_array *tr, + struct ring_buffer *buffer, + struct ring_buffer_event *event, + unsigned long flags, int pc, + struct pt_regs *regs); + +static inline void trace_buffer_unlock_commit(struct trace_array *tr, + struct ring_buffer *buffer, + struct ring_buffer_event *event, + unsigned long flags, int pc) +{ + trace_buffer_unlock_commit_regs(tr, buffer, event, flags, pc, NULL); +} + +DECLARE_PER_CPU(struct ring_buffer_event *, trace_buffered_event); +DECLARE_PER_CPU(int, trace_buffered_event_cnt); +void trace_buffered_event_disable(void); +void trace_buffered_event_enable(void); + +static inline void +__trace_event_discard_commit(struct ring_buffer *buffer, + struct ring_buffer_event *event) +{ + if (this_cpu_read(trace_buffered_event) == event) { + /* Simply release the temp buffer */ + this_cpu_dec(trace_buffered_event_cnt); + return; + } + ring_buffer_discard_commit(buffer, event); +} + +/* + * Helper function for event_trigger_unlock_commit{_regs}(). + * If there are event triggers attached to this event that requires + * filtering against its fields, then they wil be called as the + * entry already holds the field information of the current event. + * + * It also checks if the event should be discarded or not. + * It is to be discarded if the event is soft disabled and the + * event was only recorded to process triggers, or if the event + * filter is active and this event did not match the filters. + * + * Returns true if the event is discarded, false otherwise. + */ +static inline bool +__event_trigger_test_discard(struct trace_event_file *file, + struct ring_buffer *buffer, + struct ring_buffer_event *event, + void *entry, + enum event_trigger_type *tt) +{ + unsigned long eflags = file->flags; + + if (eflags & EVENT_FILE_FL_TRIGGER_COND) + *tt = event_triggers_call(file, entry); + + if (test_bit(EVENT_FILE_FL_SOFT_DISABLED_BIT, &file->flags) || + (unlikely(file->flags & EVENT_FILE_FL_FILTERED) && + !filter_match_preds(file->filter, entry))) { + __trace_event_discard_commit(buffer, event); + return true; + } + + return false; +} + +/** + * event_trigger_unlock_commit - handle triggers and finish event commit + * @file: The file pointer assoctiated to the event + * @buffer: The ring buffer that the event is being written to + * @event: The event meta data in the ring buffer + * @entry: The event itself + * @irq_flags: The state of the interrupts at the start of the event + * @pc: The state of the preempt count at the start of the event. + * + * This is a helper function to handle triggers that require data + * from the event itself. It also tests the event against filters and + * if the event is soft disabled and should be discarded. + */ +static inline void +event_trigger_unlock_commit(struct trace_event_file *file, + struct ring_buffer *buffer, + struct ring_buffer_event *event, + void *entry, unsigned long irq_flags, int pc) +{ + enum event_trigger_type tt = ETT_NONE; + + if (!__event_trigger_test_discard(file, buffer, event, entry, &tt)) + trace_buffer_unlock_commit(file->tr, buffer, event, irq_flags, pc); + + if (tt) + event_triggers_post_call(file, tt, entry); +} + +/** + * event_trigger_unlock_commit_regs - handle triggers and finish event commit + * @file: The file pointer assoctiated to the event + * @buffer: The ring buffer that the event is being written to + * @event: The event meta data in the ring buffer + * @entry: The event itself + * @irq_flags: The state of the interrupts at the start of the event + * @pc: The state of the preempt count at the start of the event. + * + * This is a helper function to handle triggers that require data + * from the event itself. It also tests the event against filters and + * if the event is soft disabled and should be discarded. + * + * Same as event_trigger_unlock_commit() but calls + * trace_buffer_unlock_commit_regs() instead of trace_buffer_unlock_commit(). + */ +static inline void +event_trigger_unlock_commit_regs(struct trace_event_file *file, + struct ring_buffer *buffer, + struct ring_buffer_event *event, + void *entry, unsigned long irq_flags, int pc, + struct pt_regs *regs) +{ + enum event_trigger_type tt = ETT_NONE; + + if (!__event_trigger_test_discard(file, buffer, event, entry, &tt)) + trace_buffer_unlock_commit_regs(file->tr, buffer, event, + irq_flags, pc, regs); + + if (tt) + event_triggers_post_call(file, tt, entry); +} + #define FILTER_PRED_INVALID ((unsigned short)-1) #define FILTER_PRED_IS_RIGHT (1 << 15) #define FILTER_PRED_FOLD (1 << 15) @@ -1161,6 +1293,15 @@ extern struct mutex event_mutex; extern struct list_head ftrace_events; extern const struct file_operations event_trigger_fops; +extern const struct file_operations event_hist_fops; + +#ifdef CONFIG_HIST_TRIGGERS +extern int register_trigger_hist_cmd(void); +extern int register_trigger_hist_enable_disable_cmds(void); +#else +static inline int register_trigger_hist_cmd(void) { return 0; } +static inline int register_trigger_hist_enable_disable_cmds(void) { return 0; } +#endif extern int register_trigger_cmds(void); extern void clear_event_triggers(struct trace_array *tr); @@ -1174,9 +1315,41 @@ struct event_trigger_data { char *filter_str; void *private_data; bool paused; + bool paused_tmp; struct list_head list; + char *name; + struct list_head named_list; + struct event_trigger_data *named_data; +}; + +/* Avoid typos */ +#define ENABLE_EVENT_STR "enable_event" +#define DISABLE_EVENT_STR "disable_event" +#define ENABLE_HIST_STR "enable_hist" +#define DISABLE_HIST_STR "disable_hist" + +struct enable_trigger_data { + struct trace_event_file *file; + bool enable; + bool hist; }; +extern int event_enable_trigger_print(struct seq_file *m, + struct event_trigger_ops *ops, + struct event_trigger_data *data); +extern void event_enable_trigger_free(struct event_trigger_ops *ops, + struct event_trigger_data *data); +extern int event_enable_trigger_func(struct event_command *cmd_ops, + struct trace_event_file *file, + char *glob, char *cmd, char *param); +extern int event_enable_register_trigger(char *glob, + struct event_trigger_ops *ops, + struct event_trigger_data *data, + struct trace_event_file *file); +extern void event_enable_unregister_trigger(char *glob, + struct event_trigger_ops *ops, + struct event_trigger_data *test, + struct trace_event_file *file); extern void trigger_data_free(struct event_trigger_data *data); extern int event_trigger_init(struct event_trigger_ops *ops, struct event_trigger_data *data); @@ -1189,7 +1362,18 @@ extern void unregister_trigger(char *glob, struct event_trigger_ops *ops, extern int set_trigger_filter(char *filter_str, struct event_trigger_data *trigger_data, struct trace_event_file *file); +extern struct event_trigger_data *find_named_trigger(const char *name); +extern bool is_named_trigger(struct event_trigger_data *test); +extern int save_named_trigger(const char *name, + struct event_trigger_data *data); +extern void del_named_trigger(struct event_trigger_data *data); +extern void pause_named_trigger(struct event_trigger_data *data); +extern void unpause_named_trigger(struct event_trigger_data *data); +extern void set_named_trigger_data(struct event_trigger_data *data, + struct event_trigger_data *named_data); extern int register_event_command(struct event_command *cmd); +extern int unregister_event_command(struct event_command *cmd); +extern int register_trigger_hist_enable_disable_cmds(void); /** * struct event_trigger_ops - callbacks for trace event triggers diff --git a/kernel/trace/trace_event_perf.c b/kernel/trace/trace_event_perf.c index 00df25fd86ef..562fa69df5d3 100644 --- a/kernel/trace/trace_event_perf.c +++ b/kernel/trace/trace_event_perf.c @@ -47,6 +47,9 @@ static int perf_trace_event_perm(struct trace_event_call *tp_event, if (perf_paranoid_tracepoint_raw() && !capable(CAP_SYS_ADMIN)) return -EPERM; + if (!is_sampling_event(p_event)) + return 0; + /* * We don't allow user space callchains for function trace * event, due to issues with page faults while tracing page @@ -260,42 +263,43 @@ void perf_trace_del(struct perf_event *p_event, int flags) tp_event->class->reg(tp_event, TRACE_REG_PERF_DEL, p_event); } -void *perf_trace_buf_prepare(int size, unsigned short type, - struct pt_regs **regs, int *rctxp) +void *perf_trace_buf_alloc(int size, struct pt_regs **regs, int *rctxp) { - struct trace_entry *entry; - unsigned long flags; char *raw_data; - int pc; + int rctx; BUILD_BUG_ON(PERF_MAX_TRACE_SIZE % sizeof(unsigned long)); if (WARN_ONCE(size > PERF_MAX_TRACE_SIZE, - "perf buffer not large enough")) + "perf buffer not large enough")) return NULL; - pc = preempt_count(); - - *rctxp = perf_swevent_get_recursion_context(); - if (*rctxp < 0) + *rctxp = rctx = perf_swevent_get_recursion_context(); + if (rctx < 0) return NULL; if (regs) - *regs = this_cpu_ptr(&__perf_regs[*rctxp]); - raw_data = this_cpu_ptr(perf_trace_buf[*rctxp]); + *regs = this_cpu_ptr(&__perf_regs[rctx]); + raw_data = this_cpu_ptr(perf_trace_buf[rctx]); /* zero the dead bytes from align to not leak stack to user */ memset(&raw_data[size - sizeof(u64)], 0, sizeof(u64)); + return raw_data; +} +EXPORT_SYMBOL_GPL(perf_trace_buf_alloc); +NOKPROBE_SYMBOL(perf_trace_buf_alloc); + +void perf_trace_buf_update(void *record, u16 type) +{ + struct trace_entry *entry = record; + int pc = preempt_count(); + unsigned long flags; - entry = (struct trace_entry *)raw_data; local_save_flags(flags); tracing_generic_entry_update(entry, flags, pc); entry->type = type; - - return raw_data; } -EXPORT_SYMBOL_GPL(perf_trace_buf_prepare); -NOKPROBE_SYMBOL(perf_trace_buf_prepare); +NOKPROBE_SYMBOL(perf_trace_buf_update); #ifdef CONFIG_FUNCTION_TRACER static void @@ -316,15 +320,16 @@ perf_ftrace_function_call(unsigned long ip, unsigned long parent_ip, BUILD_BUG_ON(ENTRY_SIZE > PERF_MAX_TRACE_SIZE); + memset(®s, 0, sizeof(regs)); perf_fetch_caller_regs(®s); - entry = perf_trace_buf_prepare(ENTRY_SIZE, TRACE_FN, NULL, &rctx); + entry = perf_trace_buf_alloc(ENTRY_SIZE, NULL, &rctx); if (!entry) return; entry->ip = ip; entry->parent_ip = parent_ip; - perf_trace_buf_submit(entry, ENTRY_SIZE, rctx, 0, + perf_trace_buf_submit(entry, ENTRY_SIZE, rctx, TRACE_FN, 1, ®s, head, NULL); #undef ENTRY_SIZE diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c index 05ddc0820771..3d4155892a1e 100644 --- a/kernel/trace/trace_events.c +++ b/kernel/trace/trace_events.c @@ -15,7 +15,7 @@ #include <linux/kthread.h> #include <linux/tracefs.h> #include <linux/uaccess.h> -#include <linux/bsearch.h> +#include <linux/vmalloc.h> #include <linux/module.h> #include <linux/ctype.h> #include <linux/sort.h> @@ -204,6 +204,24 @@ static void trace_destroy_fields(struct trace_event_call *call) } } +/* + * run-time version of trace_event_get_offsets_<call>() that returns the last + * accessible offset of trace fields excluding __dynamic_array bytes + */ +int trace_event_get_offsets(struct trace_event_call *call) +{ + struct ftrace_event_field *tail; + struct list_head *head; + + head = trace_get_fields(call); + /* + * head->next points to the last field with the largest offset, + * since it was added last by trace_define_field() + */ + tail = list_first_entry(head, struct ftrace_event_field, link); + return tail->offset + tail->size; +} + int trace_event_raw_init(struct trace_event_call *call) { int id; @@ -363,6 +381,7 @@ static int __ftrace_event_enable_disable(struct trace_event_file *file, { struct trace_event_call *call = file->event_call; struct trace_array *tr = file->tr; + unsigned long file_flags = file->flags; int ret = 0; int disable; @@ -445,6 +464,15 @@ static int __ftrace_event_enable_disable(struct trace_event_file *file, break; } + /* Enable or disable use of trace_buffered_event */ + if ((file_flags & EVENT_FILE_FL_SOFT_DISABLED) != + (file->flags & EVENT_FILE_FL_SOFT_DISABLED)) { + if (file->flags & EVENT_FILE_FL_SOFT_DISABLED) + trace_buffered_event_enable(); + else + trace_buffered_event_disable(); + } + return ret; } @@ -471,24 +499,26 @@ static void ftrace_clear_events(struct trace_array *tr) mutex_unlock(&event_mutex); } -static int cmp_pid(const void *key, const void *elt) +/* Shouldn't this be in a header? */ +extern int pid_max; + +/* Returns true if found in filter */ +static bool +find_filtered_pid(struct trace_pid_list *filtered_pids, pid_t search_pid) { - const pid_t *search_pid = key; - const pid_t *pid = elt; + /* + * If pid_max changed after filtered_pids was created, we + * by default ignore all pids greater than the previous pid_max. + */ + if (search_pid >= filtered_pids->pid_max) + return false; - if (*search_pid == *pid) - return 0; - if (*search_pid < *pid) - return -1; - return 1; + return test_bit(search_pid, filtered_pids->pids); } static bool -check_ignore_pid(struct trace_pid_list *filtered_pids, struct task_struct *task) +ignore_this_task(struct trace_pid_list *filtered_pids, struct task_struct *task) { - pid_t search_pid; - pid_t *pid; - /* * Return false, because if filtered_pids does not exist, * all pids are good to trace. @@ -496,15 +526,68 @@ check_ignore_pid(struct trace_pid_list *filtered_pids, struct task_struct *task) if (!filtered_pids) return false; - search_pid = task->pid; + return !find_filtered_pid(filtered_pids, task->pid); +} + +static void filter_add_remove_task(struct trace_pid_list *pid_list, + struct task_struct *self, + struct task_struct *task) +{ + if (!pid_list) + return; + + /* For forks, we only add if the forking task is listed */ + if (self) { + if (!find_filtered_pid(pid_list, self->pid)) + return; + } - pid = bsearch(&search_pid, filtered_pids->pids, - filtered_pids->nr_pids, sizeof(pid_t), - cmp_pid); - if (!pid) - return true; + /* Sorry, but we don't support pid_max changing after setting */ + if (task->pid >= pid_list->pid_max) + return; - return false; + /* "self" is set for forks, and NULL for exits */ + if (self) + set_bit(task->pid, pid_list->pids); + else + clear_bit(task->pid, pid_list->pids); +} + +static void +event_filter_pid_sched_process_exit(void *data, struct task_struct *task) +{ + struct trace_pid_list *pid_list; + struct trace_array *tr = data; + + pid_list = rcu_dereference_sched(tr->filtered_pids); + filter_add_remove_task(pid_list, NULL, task); +} + +static void +event_filter_pid_sched_process_fork(void *data, + struct task_struct *self, + struct task_struct *task) +{ + struct trace_pid_list *pid_list; + struct trace_array *tr = data; + + pid_list = rcu_dereference_sched(tr->filtered_pids); + filter_add_remove_task(pid_list, self, task); +} + +void trace_event_follow_fork(struct trace_array *tr, bool enable) +{ + if (enable) { + register_trace_prio_sched_process_fork(event_filter_pid_sched_process_fork, + tr, INT_MIN); + register_trace_prio_sched_process_exit(event_filter_pid_sched_process_exit, + tr, INT_MAX); + } else { + unregister_trace_sched_process_fork(event_filter_pid_sched_process_fork, + tr); + unregister_trace_sched_process_exit(event_filter_pid_sched_process_exit, + tr); + } } static void @@ -517,8 +600,8 @@ event_filter_pid_sched_switch_probe_pre(void *data, bool preempt, pid_list = rcu_dereference_sched(tr->filtered_pids); this_cpu_write(tr->trace_buffer.data->ignore_pid, - check_ignore_pid(pid_list, prev) && - check_ignore_pid(pid_list, next)); + ignore_this_task(pid_list, prev) && + ignore_this_task(pid_list, next)); } static void @@ -531,7 +614,7 @@ event_filter_pid_sched_switch_probe_post(void *data, bool preempt, pid_list = rcu_dereference_sched(tr->filtered_pids); this_cpu_write(tr->trace_buffer.data->ignore_pid, - check_ignore_pid(pid_list, next)); + ignore_this_task(pid_list, next)); } static void @@ -547,7 +630,7 @@ event_filter_pid_sched_wakeup_probe_pre(void *data, struct task_struct *task) pid_list = rcu_dereference_sched(tr->filtered_pids); this_cpu_write(tr->trace_buffer.data->ignore_pid, - check_ignore_pid(pid_list, task)); + ignore_this_task(pid_list, task)); } static void @@ -564,7 +647,7 @@ event_filter_pid_sched_wakeup_probe_post(void *data, struct task_struct *task) /* Set tracing if current is enabled */ this_cpu_write(tr->trace_buffer.data->ignore_pid, - check_ignore_pid(pid_list, current)); + ignore_this_task(pid_list, current)); } static void __ftrace_clear_event_pids(struct trace_array *tr) @@ -602,7 +685,7 @@ static void __ftrace_clear_event_pids(struct trace_array *tr) /* Wait till all users are no longer using pid filtering */ synchronize_sched(); - free_pages((unsigned long)pid_list->pids, pid_list->order); + vfree(pid_list->pids); kfree(pid_list); } @@ -946,11 +1029,32 @@ static void t_stop(struct seq_file *m, void *p) mutex_unlock(&event_mutex); } +static void * +p_next(struct seq_file *m, void *v, loff_t *pos) +{ + struct trace_array *tr = m->private; + struct trace_pid_list *pid_list = rcu_dereference_sched(tr->filtered_pids); + unsigned long pid = (unsigned long)v; + + (*pos)++; + + /* pid already is +1 of the actual prevous bit */ + pid = find_next_bit(pid_list->pids, pid_list->pid_max, pid); + + /* Return pid + 1 to allow zero to be represented */ + if (pid < pid_list->pid_max) + return (void *)(pid + 1); + + return NULL; +} + static void *p_start(struct seq_file *m, loff_t *pos) __acquires(RCU) { struct trace_pid_list *pid_list; struct trace_array *tr = m->private; + unsigned long pid; + loff_t l = 0; /* * Grab the mutex, to keep calls to p_next() having the same @@ -963,10 +1067,18 @@ static void *p_start(struct seq_file *m, loff_t *pos) pid_list = rcu_dereference_sched(tr->filtered_pids); - if (!pid_list || *pos >= pid_list->nr_pids) + if (!pid_list) return NULL; - return (void *)&pid_list->pids[*pos]; + pid = find_first_bit(pid_list->pids, pid_list->pid_max); + if (pid >= pid_list->pid_max) + return NULL; + + /* Return pid + 1 so that zero can be the exit value */ + for (pid++; pid && l < *pos; + pid = (unsigned long)p_next(m, (void *)pid, &l)) + ; + return (void *)pid; } static void p_stop(struct seq_file *m, void *p) @@ -976,25 +1088,11 @@ static void p_stop(struct seq_file *m, void *p) mutex_unlock(&event_mutex); } -static void * -p_next(struct seq_file *m, void *v, loff_t *pos) -{ - struct trace_array *tr = m->private; - struct trace_pid_list *pid_list = rcu_dereference_sched(tr->filtered_pids); - - (*pos)++; - - if (*pos >= pid_list->nr_pids) - return NULL; - - return (void *)&pid_list->pids[*pos]; -} - static int p_show(struct seq_file *m, void *v) { - pid_t *pid = v; + unsigned long pid = (unsigned long)v - 1; - seq_printf(m, "%d\n", *pid); + seq_printf(m, "%lu\n", pid); return 0; } @@ -1543,11 +1641,6 @@ show_header(struct file *filp, char __user *ubuf, size_t cnt, loff_t *ppos) return r; } -static int max_pids(struct trace_pid_list *pid_list) -{ - return (PAGE_SIZE << pid_list->order) / sizeof(pid_t); -} - static void ignore_task_cpu(void *data) { struct trace_array *tr = data; @@ -1561,7 +1654,7 @@ static void ignore_task_cpu(void *data) mutex_is_locked(&event_mutex)); this_cpu_write(tr->trace_buffer.data->ignore_pid, - check_ignore_pid(pid_list, current)); + ignore_this_task(pid_list, current)); } static ssize_t @@ -1571,7 +1664,7 @@ ftrace_event_pid_write(struct file *filp, const char __user *ubuf, struct seq_file *m = filp->private_data; struct trace_array *tr = m->private; struct trace_pid_list *filtered_pids = NULL; - struct trace_pid_list *pid_list = NULL; + struct trace_pid_list *pid_list; struct trace_event_file *file; struct trace_parser parser; unsigned long val; @@ -1579,7 +1672,7 @@ ftrace_event_pid_write(struct file *filp, const char __user *ubuf, ssize_t read = 0; ssize_t ret = 0; pid_t pid; - int i; + int nr_pids = 0; if (!cnt) return 0; @@ -1592,10 +1685,43 @@ ftrace_event_pid_write(struct file *filp, const char __user *ubuf, return -ENOMEM; mutex_lock(&event_mutex); + filtered_pids = rcu_dereference_protected(tr->filtered_pids, + lockdep_is_held(&event_mutex)); + /* - * Load as many pids into the array before doing a - * swap from the tr->filtered_pids to the new list. + * Always recreate a new array. The write is an all or nothing + * operation. Always create a new array when adding new pids by + * the user. If the operation fails, then the current list is + * not modified. */ + pid_list = kmalloc(sizeof(*pid_list), GFP_KERNEL); + if (!pid_list) { + read = -ENOMEM; + goto out; + } + pid_list->pid_max = READ_ONCE(pid_max); + /* Only truncating will shrink pid_max */ + if (filtered_pids && filtered_pids->pid_max > pid_list->pid_max) + pid_list->pid_max = filtered_pids->pid_max; + pid_list->pids = vzalloc((pid_list->pid_max + 7) >> 3); + if (!pid_list->pids) { + kfree(pid_list); + read = -ENOMEM; + goto out; + } + if (filtered_pids) { + /* copy the current bits to the new max */ + pid = find_first_bit(filtered_pids->pids, + filtered_pids->pid_max); + while (pid < filtered_pids->pid_max) { + set_bit(pid, pid_list->pids); + pid = find_next_bit(filtered_pids->pids, + filtered_pids->pid_max, + pid + 1); + nr_pids++; + } + } + while (cnt > 0) { this_pos = 0; @@ -1613,92 +1739,35 @@ ftrace_event_pid_write(struct file *filp, const char __user *ubuf, ret = -EINVAL; if (kstrtoul(parser.buffer, 0, &val)) break; - if (val > INT_MAX) + if (val >= pid_list->pid_max) break; pid = (pid_t)val; - ret = -ENOMEM; - if (!pid_list) { - pid_list = kmalloc(sizeof(*pid_list), GFP_KERNEL); - if (!pid_list) - break; - - filtered_pids = rcu_dereference_protected(tr->filtered_pids, - lockdep_is_held(&event_mutex)); - if (filtered_pids) - pid_list->order = filtered_pids->order; - else - pid_list->order = 0; - - pid_list->pids = (void *)__get_free_pages(GFP_KERNEL, - pid_list->order); - if (!pid_list->pids) - break; - - if (filtered_pids) { - pid_list->nr_pids = filtered_pids->nr_pids; - memcpy(pid_list->pids, filtered_pids->pids, - pid_list->nr_pids * sizeof(pid_t)); - } else - pid_list->nr_pids = 0; - } - - if (pid_list->nr_pids >= max_pids(pid_list)) { - pid_t *pid_page; - - pid_page = (void *)__get_free_pages(GFP_KERNEL, - pid_list->order + 1); - if (!pid_page) - break; - memcpy(pid_page, pid_list->pids, - pid_list->nr_pids * sizeof(pid_t)); - free_pages((unsigned long)pid_list->pids, pid_list->order); - - pid_list->order++; - pid_list->pids = pid_page; - } + set_bit(pid, pid_list->pids); + nr_pids++; - pid_list->pids[pid_list->nr_pids++] = pid; trace_parser_clear(&parser); ret = 0; } trace_parser_put(&parser); if (ret < 0) { - if (pid_list) - free_pages((unsigned long)pid_list->pids, pid_list->order); + vfree(pid_list->pids); kfree(pid_list); - mutex_unlock(&event_mutex); - return ret; - } - - if (!pid_list) { - mutex_unlock(&event_mutex); - return ret; + read = ret; + goto out; } - sort(pid_list->pids, pid_list->nr_pids, sizeof(pid_t), cmp_pid, NULL); - - /* Remove duplicates */ - for (i = 1; i < pid_list->nr_pids; i++) { - int start = i; - - while (i < pid_list->nr_pids && - pid_list->pids[i - 1] == pid_list->pids[i]) - i++; - - if (start != i) { - if (i < pid_list->nr_pids) { - memmove(&pid_list->pids[start], &pid_list->pids[i], - (pid_list->nr_pids - i) * sizeof(pid_t)); - pid_list->nr_pids -= i - start; - i = start; - } else - pid_list->nr_pids = start; - } + if (!nr_pids) { + /* Cleared the list of pids */ + vfree(pid_list->pids); + kfree(pid_list); + read = ret; + if (!filtered_pids) + goto out; + pid_list = NULL; } - rcu_assign_pointer(tr->filtered_pids, pid_list); list_for_each_entry(file, &tr->events, list) { @@ -1708,7 +1777,7 @@ ftrace_event_pid_write(struct file *filp, const char __user *ubuf, if (filtered_pids) { synchronize_sched(); - free_pages((unsigned long)filtered_pids->pids, filtered_pids->order); + vfree(filtered_pids->pids); kfree(filtered_pids); } else { /* @@ -1745,10 +1814,12 @@ ftrace_event_pid_write(struct file *filp, const char __user *ubuf, */ on_each_cpu(ignore_task_cpu, tr, 1); + out: mutex_unlock(&event_mutex); ret = read; - *ppos += read; + if (read > 0) + *ppos += read; return ret; } @@ -2095,9 +2166,18 @@ event_create_dir(struct dentry *parent, struct trace_event_file *file) trace_create_file("filter", 0644, file->dir, file, &ftrace_event_filter_fops); - trace_create_file("trigger", 0644, file->dir, file, - &event_trigger_fops); + /* + * Only event directories that can be enabled should have + * triggers. + */ + if (!(call->flags & TRACE_EVENT_FL_IGNORE_ENABLE)) + trace_create_file("trigger", 0644, file->dir, file, + &event_trigger_fops); +#ifdef CONFIG_HIST_TRIGGERS + trace_create_file("hist", 0444, file->dir, file, + &event_hist_fops); +#endif trace_create_file("format", 0444, file->dir, call, &ftrace_event_format_fops); @@ -3345,7 +3425,7 @@ static __init void event_trace_self_tests(void) static DEFINE_PER_CPU(atomic_t, ftrace_test_event_disable); -static struct trace_array *event_tr; +static struct trace_event_file event_trace_file __initdata; static void __init function_test_events_call(unsigned long ip, unsigned long parent_ip, @@ -3369,17 +3449,17 @@ function_test_events_call(unsigned long ip, unsigned long parent_ip, local_save_flags(flags); - event = trace_current_buffer_lock_reserve(&buffer, - TRACE_FN, sizeof(*entry), - flags, pc); + event = trace_event_buffer_lock_reserve(&buffer, &event_trace_file, + TRACE_FN, sizeof(*entry), + flags, pc); if (!event) goto out; entry = ring_buffer_event_data(event); entry->ip = ip; entry->parent_ip = parent_ip; - trace_buffer_unlock_commit(event_tr, buffer, event, flags, pc); - + event_trigger_unlock_commit(&event_trace_file, buffer, event, + entry, flags, pc); out: atomic_dec(&per_cpu(ftrace_test_event_disable, cpu)); preempt_enable_notrace(); @@ -3394,9 +3474,11 @@ static struct ftrace_ops trace_ops __initdata = static __init void event_trace_self_test_with_function(void) { int ret; - event_tr = top_trace_array(); - if (WARN_ON(!event_tr)) + + event_trace_file.tr = top_trace_array(); + if (WARN_ON(!event_trace_file.tr)) return; + ret = register_ftrace_function(&trace_ops); if (WARN_ON(ret < 0)) { pr_info("Failed to enable function tracer for event tests\n"); diff --git a/kernel/trace/trace_events_filter.c b/kernel/trace/trace_events_filter.c index b3f5051cd4e9..9daa9b3bc6d9 100644 --- a/kernel/trace/trace_events_filter.c +++ b/kernel/trace/trace_events_filter.c @@ -689,10 +689,7 @@ static void append_filter_err(struct filter_parse_state *ps, static inline struct event_filter *event_filter(struct trace_event_file *file) { - if (file->event_call->flags & TRACE_EVENT_FL_USE_CALL_FILTER) - return file->event_call->filter; - else - return file->filter; + return file->filter; } /* caller must hold event_mutex */ @@ -826,12 +823,12 @@ static void __free_preds(struct event_filter *filter) static void filter_disable(struct trace_event_file *file) { - struct trace_event_call *call = file->event_call; + unsigned long old_flags = file->flags; - if (call->flags & TRACE_EVENT_FL_USE_CALL_FILTER) - call->flags &= ~TRACE_EVENT_FL_FILTERED; - else - file->flags &= ~EVENT_FILE_FL_FILTERED; + file->flags &= ~EVENT_FILE_FL_FILTERED; + + if (old_flags != file->flags) + trace_buffered_event_disable(); } static void __free_filter(struct event_filter *filter) @@ -883,13 +880,8 @@ static int __alloc_preds(struct event_filter *filter, int n_preds) static inline void __remove_filter(struct trace_event_file *file) { - struct trace_event_call *call = file->event_call; - filter_disable(file); - if (call->flags & TRACE_EVENT_FL_USE_CALL_FILTER) - remove_filter_string(call->filter); - else - remove_filter_string(file->filter); + remove_filter_string(file->filter); } static void filter_free_subsystem_preds(struct trace_subsystem_dir *dir, @@ -906,15 +898,8 @@ static void filter_free_subsystem_preds(struct trace_subsystem_dir *dir, static inline void __free_subsystem_filter(struct trace_event_file *file) { - struct trace_event_call *call = file->event_call; - - if (call->flags & TRACE_EVENT_FL_USE_CALL_FILTER) { - __free_filter(call->filter); - call->filter = NULL; - } else { - __free_filter(file->filter); - file->filter = NULL; - } + __free_filter(file->filter); + file->filter = NULL; } static void filter_free_subsystem_filters(struct trace_subsystem_dir *dir, @@ -1718,69 +1703,43 @@ fail: static inline void event_set_filtered_flag(struct trace_event_file *file) { - struct trace_event_call *call = file->event_call; + unsigned long old_flags = file->flags; - if (call->flags & TRACE_EVENT_FL_USE_CALL_FILTER) - call->flags |= TRACE_EVENT_FL_FILTERED; - else - file->flags |= EVENT_FILE_FL_FILTERED; + file->flags |= EVENT_FILE_FL_FILTERED; + + if (old_flags != file->flags) + trace_buffered_event_enable(); } static inline void event_set_filter(struct trace_event_file *file, struct event_filter *filter) { - struct trace_event_call *call = file->event_call; - - if (call->flags & TRACE_EVENT_FL_USE_CALL_FILTER) - rcu_assign_pointer(call->filter, filter); - else - rcu_assign_pointer(file->filter, filter); + rcu_assign_pointer(file->filter, filter); } static inline void event_clear_filter(struct trace_event_file *file) { - struct trace_event_call *call = file->event_call; - - if (call->flags & TRACE_EVENT_FL_USE_CALL_FILTER) - RCU_INIT_POINTER(call->filter, NULL); - else - RCU_INIT_POINTER(file->filter, NULL); + RCU_INIT_POINTER(file->filter, NULL); } static inline void event_set_no_set_filter_flag(struct trace_event_file *file) { - struct trace_event_call *call = file->event_call; - - if (call->flags & TRACE_EVENT_FL_USE_CALL_FILTER) - call->flags |= TRACE_EVENT_FL_NO_SET_FILTER; - else - file->flags |= EVENT_FILE_FL_NO_SET_FILTER; + file->flags |= EVENT_FILE_FL_NO_SET_FILTER; } static inline void event_clear_no_set_filter_flag(struct trace_event_file *file) { - struct trace_event_call *call = file->event_call; - - if (call->flags & TRACE_EVENT_FL_USE_CALL_FILTER) - call->flags &= ~TRACE_EVENT_FL_NO_SET_FILTER; - else - file->flags &= ~EVENT_FILE_FL_NO_SET_FILTER; + file->flags &= ~EVENT_FILE_FL_NO_SET_FILTER; } static inline bool event_no_set_filter_flag(struct trace_event_file *file) { - struct trace_event_call *call = file->event_call; - if (file->flags & EVENT_FILE_FL_NO_SET_FILTER) return true; - if ((call->flags & TRACE_EVENT_FL_USE_CALL_FILTER) && - (call->flags & TRACE_EVENT_FL_NO_SET_FILTER)) - return true; - return false; } diff --git a/kernel/trace/trace_events_hist.c b/kernel/trace/trace_events_hist.c new file mode 100644 index 000000000000..0c05b8a99806 --- /dev/null +++ b/kernel/trace/trace_events_hist.c @@ -0,0 +1,1755 @@ +/* + * trace_events_hist - trace event hist triggers + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * Copyright (C) 2015 Tom Zanussi <tom.zanussi@linux.intel.com> + */ + +#include <linux/module.h> +#include <linux/kallsyms.h> +#include <linux/mutex.h> +#include <linux/slab.h> +#include <linux/stacktrace.h> + +#include "tracing_map.h" +#include "trace.h" + +struct hist_field; + +typedef u64 (*hist_field_fn_t) (struct hist_field *field, void *event); + +struct hist_field { + struct ftrace_event_field *field; + unsigned long flags; + hist_field_fn_t fn; + unsigned int size; + unsigned int offset; +}; + +static u64 hist_field_none(struct hist_field *field, void *event) +{ + return 0; +} + +static u64 hist_field_counter(struct hist_field *field, void *event) +{ + return 1; +} + +static u64 hist_field_string(struct hist_field *hist_field, void *event) +{ + char *addr = (char *)(event + hist_field->field->offset); + + return (u64)(unsigned long)addr; +} + +static u64 hist_field_dynstring(struct hist_field *hist_field, void *event) +{ + u32 str_item = *(u32 *)(event + hist_field->field->offset); + int str_loc = str_item & 0xffff; + char *addr = (char *)(event + str_loc); + + return (u64)(unsigned long)addr; +} + +static u64 hist_field_pstring(struct hist_field *hist_field, void *event) +{ + char **addr = (char **)(event + hist_field->field->offset); + + return (u64)(unsigned long)*addr; +} + +static u64 hist_field_log2(struct hist_field *hist_field, void *event) +{ + u64 val = *(u64 *)(event + hist_field->field->offset); + + return (u64) ilog2(roundup_pow_of_two(val)); +} + +#define DEFINE_HIST_FIELD_FN(type) \ +static u64 hist_field_##type(struct hist_field *hist_field, void *event)\ +{ \ + type *addr = (type *)(event + hist_field->field->offset); \ + \ + return (u64)(unsigned long)*addr; \ +} + +DEFINE_HIST_FIELD_FN(s64); +DEFINE_HIST_FIELD_FN(u64); +DEFINE_HIST_FIELD_FN(s32); +DEFINE_HIST_FIELD_FN(u32); +DEFINE_HIST_FIELD_FN(s16); +DEFINE_HIST_FIELD_FN(u16); +DEFINE_HIST_FIELD_FN(s8); +DEFINE_HIST_FIELD_FN(u8); + +#define for_each_hist_field(i, hist_data) \ + for ((i) = 0; (i) < (hist_data)->n_fields; (i)++) + +#define for_each_hist_val_field(i, hist_data) \ + for ((i) = 0; (i) < (hist_data)->n_vals; (i)++) + +#define for_each_hist_key_field(i, hist_data) \ + for ((i) = (hist_data)->n_vals; (i) < (hist_data)->n_fields; (i)++) + +#define HIST_STACKTRACE_DEPTH 16 +#define HIST_STACKTRACE_SIZE (HIST_STACKTRACE_DEPTH * sizeof(unsigned long)) +#define HIST_STACKTRACE_SKIP 5 + +#define HITCOUNT_IDX 0 +#define HIST_KEY_SIZE_MAX (MAX_FILTER_STR_VAL + HIST_STACKTRACE_SIZE) + +enum hist_field_flags { + HIST_FIELD_FL_HITCOUNT = 1, + HIST_FIELD_FL_KEY = 2, + HIST_FIELD_FL_STRING = 4, + HIST_FIELD_FL_HEX = 8, + HIST_FIELD_FL_SYM = 16, + HIST_FIELD_FL_SYM_OFFSET = 32, + HIST_FIELD_FL_EXECNAME = 64, + HIST_FIELD_FL_SYSCALL = 128, + HIST_FIELD_FL_STACKTRACE = 256, + HIST_FIELD_FL_LOG2 = 512, +}; + +struct hist_trigger_attrs { + char *keys_str; + char *vals_str; + char *sort_key_str; + char *name; + bool pause; + bool cont; + bool clear; + unsigned int map_bits; +}; + +struct hist_trigger_data { + struct hist_field *fields[TRACING_MAP_FIELDS_MAX]; + unsigned int n_vals; + unsigned int n_keys; + unsigned int n_fields; + unsigned int key_size; + struct tracing_map_sort_key sort_keys[TRACING_MAP_SORT_KEYS_MAX]; + unsigned int n_sort_keys; + struct trace_event_file *event_file; + struct hist_trigger_attrs *attrs; + struct tracing_map *map; +}; + +static hist_field_fn_t select_value_fn(int field_size, int field_is_signed) +{ + hist_field_fn_t fn = NULL; + + switch (field_size) { + case 8: + if (field_is_signed) + fn = hist_field_s64; + else + fn = hist_field_u64; + break; + case 4: + if (field_is_signed) + fn = hist_field_s32; + else + fn = hist_field_u32; + break; + case 2: + if (field_is_signed) + fn = hist_field_s16; + else + fn = hist_field_u16; + break; + case 1: + if (field_is_signed) + fn = hist_field_s8; + else + fn = hist_field_u8; + break; + } + + return fn; +} + +static int parse_map_size(char *str) +{ + unsigned long size, map_bits; + int ret; + + strsep(&str, "="); + if (!str) { + ret = -EINVAL; + goto out; + } + + ret = kstrtoul(str, 0, &size); + if (ret) + goto out; + + map_bits = ilog2(roundup_pow_of_two(size)); + if (map_bits < TRACING_MAP_BITS_MIN || + map_bits > TRACING_MAP_BITS_MAX) + ret = -EINVAL; + else + ret = map_bits; + out: + return ret; +} + +static void destroy_hist_trigger_attrs(struct hist_trigger_attrs *attrs) +{ + if (!attrs) + return; + + kfree(attrs->name); + kfree(attrs->sort_key_str); + kfree(attrs->keys_str); + kfree(attrs->vals_str); + kfree(attrs); +} + +static struct hist_trigger_attrs *parse_hist_trigger_attrs(char *trigger_str) +{ + struct hist_trigger_attrs *attrs; + int ret = 0; + + attrs = kzalloc(sizeof(*attrs), GFP_KERNEL); + if (!attrs) + return ERR_PTR(-ENOMEM); + + while (trigger_str) { + char *str = strsep(&trigger_str, ":"); + + if ((strncmp(str, "key=", strlen("key=")) == 0) || + (strncmp(str, "keys=", strlen("keys=")) == 0)) + attrs->keys_str = kstrdup(str, GFP_KERNEL); + else if ((strncmp(str, "val=", strlen("val=")) == 0) || + (strncmp(str, "vals=", strlen("vals=")) == 0) || + (strncmp(str, "values=", strlen("values=")) == 0)) + attrs->vals_str = kstrdup(str, GFP_KERNEL); + else if (strncmp(str, "sort=", strlen("sort=")) == 0) + attrs->sort_key_str = kstrdup(str, GFP_KERNEL); + else if (strncmp(str, "name=", strlen("name=")) == 0) + attrs->name = kstrdup(str, GFP_KERNEL); + else if (strcmp(str, "pause") == 0) + attrs->pause = true; + else if ((strcmp(str, "cont") == 0) || + (strcmp(str, "continue") == 0)) + attrs->cont = true; + else if (strcmp(str, "clear") == 0) + attrs->clear = true; + else if (strncmp(str, "size=", strlen("size=")) == 0) { + int map_bits = parse_map_size(str); + + if (map_bits < 0) { + ret = map_bits; + goto free; + } + attrs->map_bits = map_bits; + } else { + ret = -EINVAL; + goto free; + } + } + + if (!attrs->keys_str) { + ret = -EINVAL; + goto free; + } + + return attrs; + free: + destroy_hist_trigger_attrs(attrs); + + return ERR_PTR(ret); +} + +static inline void save_comm(char *comm, struct task_struct *task) +{ + if (!task->pid) { + strcpy(comm, "<idle>"); + return; + } + + if (WARN_ON_ONCE(task->pid < 0)) { + strcpy(comm, "<XXX>"); + return; + } + + memcpy(comm, task->comm, TASK_COMM_LEN); +} + +static void hist_trigger_elt_comm_free(struct tracing_map_elt *elt) +{ + kfree((char *)elt->private_data); +} + +static int hist_trigger_elt_comm_alloc(struct tracing_map_elt *elt) +{ + struct hist_trigger_data *hist_data = elt->map->private_data; + struct hist_field *key_field; + unsigned int i; + + for_each_hist_key_field(i, hist_data) { + key_field = hist_data->fields[i]; + + if (key_field->flags & HIST_FIELD_FL_EXECNAME) { + unsigned int size = TASK_COMM_LEN + 1; + + elt->private_data = kzalloc(size, GFP_KERNEL); + if (!elt->private_data) + return -ENOMEM; + break; + } + } + + return 0; +} + +static void hist_trigger_elt_comm_copy(struct tracing_map_elt *to, + struct tracing_map_elt *from) +{ + char *comm_from = from->private_data; + char *comm_to = to->private_data; + + if (comm_from) + memcpy(comm_to, comm_from, TASK_COMM_LEN + 1); +} + +static void hist_trigger_elt_comm_init(struct tracing_map_elt *elt) +{ + char *comm = elt->private_data; + + if (comm) + save_comm(comm, current); +} + +static const struct tracing_map_ops hist_trigger_elt_comm_ops = { + .elt_alloc = hist_trigger_elt_comm_alloc, + .elt_copy = hist_trigger_elt_comm_copy, + .elt_free = hist_trigger_elt_comm_free, + .elt_init = hist_trigger_elt_comm_init, +}; + +static void destroy_hist_field(struct hist_field *hist_field) +{ + kfree(hist_field); +} + +static struct hist_field *create_hist_field(struct ftrace_event_field *field, + unsigned long flags) +{ + struct hist_field *hist_field; + + if (field && is_function_field(field)) + return NULL; + + hist_field = kzalloc(sizeof(struct hist_field), GFP_KERNEL); + if (!hist_field) + return NULL; + + if (flags & HIST_FIELD_FL_HITCOUNT) { + hist_field->fn = hist_field_counter; + goto out; + } + + if (flags & HIST_FIELD_FL_STACKTRACE) { + hist_field->fn = hist_field_none; + goto out; + } + + if (flags & HIST_FIELD_FL_LOG2) { + hist_field->fn = hist_field_log2; + goto out; + } + + if (WARN_ON_ONCE(!field)) + goto out; + + if (is_string_field(field)) { + flags |= HIST_FIELD_FL_STRING; + + if (field->filter_type == FILTER_STATIC_STRING) + hist_field->fn = hist_field_string; + else if (field->filter_type == FILTER_DYN_STRING) + hist_field->fn = hist_field_dynstring; + else + hist_field->fn = hist_field_pstring; + } else { + hist_field->fn = select_value_fn(field->size, + field->is_signed); + if (!hist_field->fn) { + destroy_hist_field(hist_field); + return NULL; + } + } + out: + hist_field->field = field; + hist_field->flags = flags; + + return hist_field; +} + +static void destroy_hist_fields(struct hist_trigger_data *hist_data) +{ + unsigned int i; + + for (i = 0; i < TRACING_MAP_FIELDS_MAX; i++) { + if (hist_data->fields[i]) { + destroy_hist_field(hist_data->fields[i]); + hist_data->fields[i] = NULL; + } + } +} + +static int create_hitcount_val(struct hist_trigger_data *hist_data) +{ + hist_data->fields[HITCOUNT_IDX] = + create_hist_field(NULL, HIST_FIELD_FL_HITCOUNT); + if (!hist_data->fields[HITCOUNT_IDX]) + return -ENOMEM; + + hist_data->n_vals++; + + if (WARN_ON(hist_data->n_vals > TRACING_MAP_VALS_MAX)) + return -EINVAL; + + return 0; +} + +static int create_val_field(struct hist_trigger_data *hist_data, + unsigned int val_idx, + struct trace_event_file *file, + char *field_str) +{ + struct ftrace_event_field *field = NULL; + unsigned long flags = 0; + char *field_name; + int ret = 0; + + if (WARN_ON(val_idx >= TRACING_MAP_VALS_MAX)) + return -EINVAL; + + field_name = strsep(&field_str, "."); + if (field_str) { + if (strcmp(field_str, "hex") == 0) + flags |= HIST_FIELD_FL_HEX; + else { + ret = -EINVAL; + goto out; + } + } + + field = trace_find_event_field(file->event_call, field_name); + if (!field) { + ret = -EINVAL; + goto out; + } + + hist_data->fields[val_idx] = create_hist_field(field, flags); + if (!hist_data->fields[val_idx]) { + ret = -ENOMEM; + goto out; + } + + ++hist_data->n_vals; + + if (WARN_ON(hist_data->n_vals > TRACING_MAP_VALS_MAX)) + ret = -EINVAL; + out: + return ret; +} + +static int create_val_fields(struct hist_trigger_data *hist_data, + struct trace_event_file *file) +{ + char *fields_str, *field_str; + unsigned int i, j; + int ret; + + ret = create_hitcount_val(hist_data); + if (ret) + goto out; + + fields_str = hist_data->attrs->vals_str; + if (!fields_str) + goto out; + + strsep(&fields_str, "="); + if (!fields_str) + goto out; + + for (i = 0, j = 1; i < TRACING_MAP_VALS_MAX && + j < TRACING_MAP_VALS_MAX; i++) { + field_str = strsep(&fields_str, ","); + if (!field_str) + break; + if (strcmp(field_str, "hitcount") == 0) + continue; + ret = create_val_field(hist_data, j++, file, field_str); + if (ret) + goto out; + } + if (fields_str && (strcmp(fields_str, "hitcount") != 0)) + ret = -EINVAL; + out: + return ret; +} + +static int create_key_field(struct hist_trigger_data *hist_data, + unsigned int key_idx, + unsigned int key_offset, + struct trace_event_file *file, + char *field_str) +{ + struct ftrace_event_field *field = NULL; + unsigned long flags = 0; + unsigned int key_size; + int ret = 0; + + if (WARN_ON(key_idx >= TRACING_MAP_FIELDS_MAX)) + return -EINVAL; + + flags |= HIST_FIELD_FL_KEY; + + if (strcmp(field_str, "stacktrace") == 0) { + flags |= HIST_FIELD_FL_STACKTRACE; + key_size = sizeof(unsigned long) * HIST_STACKTRACE_DEPTH; + } else { + char *field_name = strsep(&field_str, "."); + + if (field_str) { + if (strcmp(field_str, "hex") == 0) + flags |= HIST_FIELD_FL_HEX; + else if (strcmp(field_str, "sym") == 0) + flags |= HIST_FIELD_FL_SYM; + else if (strcmp(field_str, "sym-offset") == 0) + flags |= HIST_FIELD_FL_SYM_OFFSET; + else if ((strcmp(field_str, "execname") == 0) && + (strcmp(field_name, "common_pid") == 0)) + flags |= HIST_FIELD_FL_EXECNAME; + else if (strcmp(field_str, "syscall") == 0) + flags |= HIST_FIELD_FL_SYSCALL; + else if (strcmp(field_str, "log2") == 0) + flags |= HIST_FIELD_FL_LOG2; + else { + ret = -EINVAL; + goto out; + } + } + + field = trace_find_event_field(file->event_call, field_name); + if (!field) { + ret = -EINVAL; + goto out; + } + + if (is_string_field(field)) + key_size = MAX_FILTER_STR_VAL; + else + key_size = field->size; + } + + hist_data->fields[key_idx] = create_hist_field(field, flags); + if (!hist_data->fields[key_idx]) { + ret = -ENOMEM; + goto out; + } + + key_size = ALIGN(key_size, sizeof(u64)); + hist_data->fields[key_idx]->size = key_size; + hist_data->fields[key_idx]->offset = key_offset; + hist_data->key_size += key_size; + if (hist_data->key_size > HIST_KEY_SIZE_MAX) { + ret = -EINVAL; + goto out; + } + + hist_data->n_keys++; + + if (WARN_ON(hist_data->n_keys > TRACING_MAP_KEYS_MAX)) + return -EINVAL; + + ret = key_size; + out: + return ret; +} + +static int create_key_fields(struct hist_trigger_data *hist_data, + struct trace_event_file *file) +{ + unsigned int i, key_offset = 0, n_vals = hist_data->n_vals; + char *fields_str, *field_str; + int ret = -EINVAL; + + fields_str = hist_data->attrs->keys_str; + if (!fields_str) + goto out; + + strsep(&fields_str, "="); + if (!fields_str) + goto out; + + for (i = n_vals; i < n_vals + TRACING_MAP_KEYS_MAX; i++) { + field_str = strsep(&fields_str, ","); + if (!field_str) + break; + ret = create_key_field(hist_data, i, key_offset, + file, field_str); + if (ret < 0) + goto out; + key_offset += ret; + } + if (fields_str) { + ret = -EINVAL; + goto out; + } + ret = 0; + out: + return ret; +} + +static int create_hist_fields(struct hist_trigger_data *hist_data, + struct trace_event_file *file) +{ + int ret; + + ret = create_val_fields(hist_data, file); + if (ret) + goto out; + + ret = create_key_fields(hist_data, file); + if (ret) + goto out; + + hist_data->n_fields = hist_data->n_vals + hist_data->n_keys; + out: + return ret; +} + +static int is_descending(const char *str) +{ + if (!str) + return 0; + + if (strcmp(str, "descending") == 0) + return 1; + + if (strcmp(str, "ascending") == 0) + return 0; + + return -EINVAL; +} + +static int create_sort_keys(struct hist_trigger_data *hist_data) +{ + char *fields_str = hist_data->attrs->sort_key_str; + struct ftrace_event_field *field = NULL; + struct tracing_map_sort_key *sort_key; + int descending, ret = 0; + unsigned int i, j; + + hist_data->n_sort_keys = 1; /* we always have at least one, hitcount */ + + if (!fields_str) + goto out; + + strsep(&fields_str, "="); + if (!fields_str) { + ret = -EINVAL; + goto out; + } + + for (i = 0; i < TRACING_MAP_SORT_KEYS_MAX; i++) { + char *field_str, *field_name; + + sort_key = &hist_data->sort_keys[i]; + + field_str = strsep(&fields_str, ","); + if (!field_str) { + if (i == 0) + ret = -EINVAL; + break; + } + + if ((i == TRACING_MAP_SORT_KEYS_MAX - 1) && fields_str) { + ret = -EINVAL; + break; + } + + field_name = strsep(&field_str, "."); + if (!field_name) { + ret = -EINVAL; + break; + } + + if (strcmp(field_name, "hitcount") == 0) { + descending = is_descending(field_str); + if (descending < 0) { + ret = descending; + break; + } + sort_key->descending = descending; + continue; + } + + for (j = 1; j < hist_data->n_fields; j++) { + field = hist_data->fields[j]->field; + if (field && (strcmp(field_name, field->name) == 0)) { + sort_key->field_idx = j; + descending = is_descending(field_str); + if (descending < 0) { + ret = descending; + goto out; + } + sort_key->descending = descending; + break; + } + } + if (j == hist_data->n_fields) { + ret = -EINVAL; + break; + } + } + hist_data->n_sort_keys = i; + out: + return ret; +} + +static void destroy_hist_data(struct hist_trigger_data *hist_data) +{ + destroy_hist_trigger_attrs(hist_data->attrs); + destroy_hist_fields(hist_data); + tracing_map_destroy(hist_data->map); + kfree(hist_data); +} + +static int create_tracing_map_fields(struct hist_trigger_data *hist_data) +{ + struct tracing_map *map = hist_data->map; + struct ftrace_event_field *field; + struct hist_field *hist_field; + int i, idx; + + for_each_hist_field(i, hist_data) { + hist_field = hist_data->fields[i]; + if (hist_field->flags & HIST_FIELD_FL_KEY) { + tracing_map_cmp_fn_t cmp_fn; + + field = hist_field->field; + + if (hist_field->flags & HIST_FIELD_FL_STACKTRACE) + cmp_fn = tracing_map_cmp_none; + else if (is_string_field(field)) + cmp_fn = tracing_map_cmp_string; + else + cmp_fn = tracing_map_cmp_num(field->size, + field->is_signed); + idx = tracing_map_add_key_field(map, + hist_field->offset, + cmp_fn); + + } else + idx = tracing_map_add_sum_field(map); + + if (idx < 0) + return idx; + } + + return 0; +} + +static bool need_tracing_map_ops(struct hist_trigger_data *hist_data) +{ + struct hist_field *key_field; + unsigned int i; + + for_each_hist_key_field(i, hist_data) { + key_field = hist_data->fields[i]; + + if (key_field->flags & HIST_FIELD_FL_EXECNAME) + return true; + } + + return false; +} + +static struct hist_trigger_data * +create_hist_data(unsigned int map_bits, + struct hist_trigger_attrs *attrs, + struct trace_event_file *file) +{ + const struct tracing_map_ops *map_ops = NULL; + struct hist_trigger_data *hist_data; + int ret = 0; + + hist_data = kzalloc(sizeof(*hist_data), GFP_KERNEL); + if (!hist_data) + return ERR_PTR(-ENOMEM); + + hist_data->attrs = attrs; + + ret = create_hist_fields(hist_data, file); + if (ret) + goto free; + + ret = create_sort_keys(hist_data); + if (ret) + goto free; + + if (need_tracing_map_ops(hist_data)) + map_ops = &hist_trigger_elt_comm_ops; + + hist_data->map = tracing_map_create(map_bits, hist_data->key_size, + map_ops, hist_data); + if (IS_ERR(hist_data->map)) { + ret = PTR_ERR(hist_data->map); + hist_data->map = NULL; + goto free; + } + + ret = create_tracing_map_fields(hist_data); + if (ret) + goto free; + + ret = tracing_map_init(hist_data->map); + if (ret) + goto free; + + hist_data->event_file = file; + out: + return hist_data; + free: + hist_data->attrs = NULL; + + destroy_hist_data(hist_data); + + hist_data = ERR_PTR(ret); + + goto out; +} + +static void hist_trigger_elt_update(struct hist_trigger_data *hist_data, + struct tracing_map_elt *elt, + void *rec) +{ + struct hist_field *hist_field; + unsigned int i; + u64 hist_val; + + for_each_hist_val_field(i, hist_data) { + hist_field = hist_data->fields[i]; + hist_val = hist_field->fn(hist_field, rec); + tracing_map_update_sum(elt, i, hist_val); + } +} + +static inline void add_to_key(char *compound_key, void *key, + struct hist_field *key_field, void *rec) +{ + size_t size = key_field->size; + + if (key_field->flags & HIST_FIELD_FL_STRING) { + struct ftrace_event_field *field; + + field = key_field->field; + if (field->filter_type == FILTER_DYN_STRING) + size = *(u32 *)(rec + field->offset) >> 16; + else if (field->filter_type == FILTER_PTR_STRING) + size = strlen(key); + else if (field->filter_type == FILTER_STATIC_STRING) + size = field->size; + + /* ensure NULL-termination */ + if (size > key_field->size - 1) + size = key_field->size - 1; + } + + memcpy(compound_key + key_field->offset, key, size); +} + +static void event_hist_trigger(struct event_trigger_data *data, void *rec) +{ + struct hist_trigger_data *hist_data = data->private_data; + bool use_compound_key = (hist_data->n_keys > 1); + unsigned long entries[HIST_STACKTRACE_DEPTH]; + char compound_key[HIST_KEY_SIZE_MAX]; + struct stack_trace stacktrace; + struct hist_field *key_field; + struct tracing_map_elt *elt; + u64 field_contents; + void *key = NULL; + unsigned int i; + + memset(compound_key, 0, hist_data->key_size); + + for_each_hist_key_field(i, hist_data) { + key_field = hist_data->fields[i]; + + if (key_field->flags & HIST_FIELD_FL_STACKTRACE) { + stacktrace.max_entries = HIST_STACKTRACE_DEPTH; + stacktrace.entries = entries; + stacktrace.nr_entries = 0; + stacktrace.skip = HIST_STACKTRACE_SKIP; + + memset(stacktrace.entries, 0, HIST_STACKTRACE_SIZE); + save_stack_trace(&stacktrace); + + key = entries; + } else { + field_contents = key_field->fn(key_field, rec); + if (key_field->flags & HIST_FIELD_FL_STRING) { + key = (void *)(unsigned long)field_contents; + use_compound_key = true; + } else + key = (void *)&field_contents; + } + + if (use_compound_key) + add_to_key(compound_key, key, key_field, rec); + } + + if (use_compound_key) + key = compound_key; + + elt = tracing_map_insert(hist_data->map, key); + if (elt) + hist_trigger_elt_update(hist_data, elt, rec); +} + +static void hist_trigger_stacktrace_print(struct seq_file *m, + unsigned long *stacktrace_entries, + unsigned int max_entries) +{ + char str[KSYM_SYMBOL_LEN]; + unsigned int spaces = 8; + unsigned int i; + + for (i = 0; i < max_entries; i++) { + if (stacktrace_entries[i] == ULONG_MAX) + return; + + seq_printf(m, "%*c", 1 + spaces, ' '); + sprint_symbol(str, stacktrace_entries[i]); + seq_printf(m, "%s\n", str); + } +} + +static void +hist_trigger_entry_print(struct seq_file *m, + struct hist_trigger_data *hist_data, void *key, + struct tracing_map_elt *elt) +{ + struct hist_field *key_field; + char str[KSYM_SYMBOL_LEN]; + bool multiline = false; + unsigned int i; + u64 uval; + + seq_puts(m, "{ "); + + for_each_hist_key_field(i, hist_data) { + key_field = hist_data->fields[i]; + + if (i > hist_data->n_vals) + seq_puts(m, ", "); + + if (key_field->flags & HIST_FIELD_FL_HEX) { + uval = *(u64 *)(key + key_field->offset); + seq_printf(m, "%s: %llx", + key_field->field->name, uval); + } else if (key_field->flags & HIST_FIELD_FL_SYM) { + uval = *(u64 *)(key + key_field->offset); + sprint_symbol_no_offset(str, uval); + seq_printf(m, "%s: [%llx] %-45s", + key_field->field->name, uval, str); + } else if (key_field->flags & HIST_FIELD_FL_SYM_OFFSET) { + uval = *(u64 *)(key + key_field->offset); + sprint_symbol(str, uval); + seq_printf(m, "%s: [%llx] %-55s", + key_field->field->name, uval, str); + } else if (key_field->flags & HIST_FIELD_FL_EXECNAME) { + char *comm = elt->private_data; + + uval = *(u64 *)(key + key_field->offset); + seq_printf(m, "%s: %-16s[%10llu]", + key_field->field->name, comm, uval); + } else if (key_field->flags & HIST_FIELD_FL_SYSCALL) { + const char *syscall_name; + + uval = *(u64 *)(key + key_field->offset); + syscall_name = get_syscall_name(uval); + if (!syscall_name) + syscall_name = "unknown_syscall"; + + seq_printf(m, "%s: %-30s[%3llu]", + key_field->field->name, syscall_name, uval); + } else if (key_field->flags & HIST_FIELD_FL_STACKTRACE) { + seq_puts(m, "stacktrace:\n"); + hist_trigger_stacktrace_print(m, + key + key_field->offset, + HIST_STACKTRACE_DEPTH); + multiline = true; + } else if (key_field->flags & HIST_FIELD_FL_LOG2) { + seq_printf(m, "%s: ~ 2^%-2llu", key_field->field->name, + *(u64 *)(key + key_field->offset)); + } else if (key_field->flags & HIST_FIELD_FL_STRING) { + seq_printf(m, "%s: %-50s", key_field->field->name, + (char *)(key + key_field->offset)); + } else { + uval = *(u64 *)(key + key_field->offset); + seq_printf(m, "%s: %10llu", key_field->field->name, + uval); + } + } + + if (!multiline) + seq_puts(m, " "); + + seq_puts(m, "}"); + + seq_printf(m, " hitcount: %10llu", + tracing_map_read_sum(elt, HITCOUNT_IDX)); + + for (i = 1; i < hist_data->n_vals; i++) { + if (hist_data->fields[i]->flags & HIST_FIELD_FL_HEX) { + seq_printf(m, " %s: %10llx", + hist_data->fields[i]->field->name, + tracing_map_read_sum(elt, i)); + } else { + seq_printf(m, " %s: %10llu", + hist_data->fields[i]->field->name, + tracing_map_read_sum(elt, i)); + } + } + + seq_puts(m, "\n"); +} + +static int print_entries(struct seq_file *m, + struct hist_trigger_data *hist_data) +{ + struct tracing_map_sort_entry **sort_entries = NULL; + struct tracing_map *map = hist_data->map; + int i, n_entries; + + n_entries = tracing_map_sort_entries(map, hist_data->sort_keys, + hist_data->n_sort_keys, + &sort_entries); + if (n_entries < 0) + return n_entries; + + for (i = 0; i < n_entries; i++) + hist_trigger_entry_print(m, hist_data, + sort_entries[i]->key, + sort_entries[i]->elt); + + tracing_map_destroy_sort_entries(sort_entries, n_entries); + + return n_entries; +} + +static void hist_trigger_show(struct seq_file *m, + struct event_trigger_data *data, int n) +{ + struct hist_trigger_data *hist_data; + int n_entries, ret = 0; + + if (n > 0) + seq_puts(m, "\n\n"); + + seq_puts(m, "# event histogram\n#\n# trigger info: "); + data->ops->print(m, data->ops, data); + seq_puts(m, "#\n\n"); + + hist_data = data->private_data; + n_entries = print_entries(m, hist_data); + if (n_entries < 0) { + ret = n_entries; + n_entries = 0; + } + + seq_printf(m, "\nTotals:\n Hits: %llu\n Entries: %u\n Dropped: %llu\n", + (u64)atomic64_read(&hist_data->map->hits), + n_entries, (u64)atomic64_read(&hist_data->map->drops)); +} + +static int hist_show(struct seq_file *m, void *v) +{ + struct event_trigger_data *data; + struct trace_event_file *event_file; + int n = 0, ret = 0; + + mutex_lock(&event_mutex); + + event_file = event_file_data(m->private); + if (unlikely(!event_file)) { + ret = -ENODEV; + goto out_unlock; + } + + list_for_each_entry_rcu(data, &event_file->triggers, list) { + if (data->cmd_ops->trigger_type == ETT_EVENT_HIST) + hist_trigger_show(m, data, n++); + } + + out_unlock: + mutex_unlock(&event_mutex); + + return ret; +} + +static int event_hist_open(struct inode *inode, struct file *file) +{ + return single_open(file, hist_show, file); +} + +const struct file_operations event_hist_fops = { + .open = event_hist_open, + .read = seq_read, + .llseek = seq_lseek, + .release = single_release, +}; + +static const char *get_hist_field_flags(struct hist_field *hist_field) +{ + const char *flags_str = NULL; + + if (hist_field->flags & HIST_FIELD_FL_HEX) + flags_str = "hex"; + else if (hist_field->flags & HIST_FIELD_FL_SYM) + flags_str = "sym"; + else if (hist_field->flags & HIST_FIELD_FL_SYM_OFFSET) + flags_str = "sym-offset"; + else if (hist_field->flags & HIST_FIELD_FL_EXECNAME) + flags_str = "execname"; + else if (hist_field->flags & HIST_FIELD_FL_SYSCALL) + flags_str = "syscall"; + else if (hist_field->flags & HIST_FIELD_FL_LOG2) + flags_str = "log2"; + + return flags_str; +} + +static void hist_field_print(struct seq_file *m, struct hist_field *hist_field) +{ + seq_printf(m, "%s", hist_field->field->name); + if (hist_field->flags) { + const char *flags_str = get_hist_field_flags(hist_field); + + if (flags_str) + seq_printf(m, ".%s", flags_str); + } +} + +static int event_hist_trigger_print(struct seq_file *m, + struct event_trigger_ops *ops, + struct event_trigger_data *data) +{ + struct hist_trigger_data *hist_data = data->private_data; + struct hist_field *key_field; + unsigned int i; + + seq_puts(m, "hist:"); + + if (data->name) + seq_printf(m, "%s:", data->name); + + seq_puts(m, "keys="); + + for_each_hist_key_field(i, hist_data) { + key_field = hist_data->fields[i]; + + if (i > hist_data->n_vals) + seq_puts(m, ","); + + if (key_field->flags & HIST_FIELD_FL_STACKTRACE) + seq_puts(m, "stacktrace"); + else + hist_field_print(m, key_field); + } + + seq_puts(m, ":vals="); + + for_each_hist_val_field(i, hist_data) { + if (i == HITCOUNT_IDX) + seq_puts(m, "hitcount"); + else { + seq_puts(m, ","); + hist_field_print(m, hist_data->fields[i]); + } + } + + seq_puts(m, ":sort="); + + for (i = 0; i < hist_data->n_sort_keys; i++) { + struct tracing_map_sort_key *sort_key; + + sort_key = &hist_data->sort_keys[i]; + + if (i > 0) + seq_puts(m, ","); + + if (sort_key->field_idx == HITCOUNT_IDX) + seq_puts(m, "hitcount"); + else { + unsigned int idx = sort_key->field_idx; + + if (WARN_ON(idx >= TRACING_MAP_FIELDS_MAX)) + return -EINVAL; + + hist_field_print(m, hist_data->fields[idx]); + } + + if (sort_key->descending) + seq_puts(m, ".descending"); + } + + seq_printf(m, ":size=%u", (1 << hist_data->map->map_bits)); + + if (data->filter_str) + seq_printf(m, " if %s", data->filter_str); + + if (data->paused) + seq_puts(m, " [paused]"); + else + seq_puts(m, " [active]"); + + seq_putc(m, '\n'); + + return 0; +} + +static int event_hist_trigger_init(struct event_trigger_ops *ops, + struct event_trigger_data *data) +{ + struct hist_trigger_data *hist_data = data->private_data; + + if (!data->ref && hist_data->attrs->name) + save_named_trigger(hist_data->attrs->name, data); + + data->ref++; + + return 0; +} + +static void event_hist_trigger_free(struct event_trigger_ops *ops, + struct event_trigger_data *data) +{ + struct hist_trigger_data *hist_data = data->private_data; + + if (WARN_ON_ONCE(data->ref <= 0)) + return; + + data->ref--; + if (!data->ref) { + if (data->name) + del_named_trigger(data); + trigger_data_free(data); + destroy_hist_data(hist_data); + } +} + +static struct event_trigger_ops event_hist_trigger_ops = { + .func = event_hist_trigger, + .print = event_hist_trigger_print, + .init = event_hist_trigger_init, + .free = event_hist_trigger_free, +}; + +static int event_hist_trigger_named_init(struct event_trigger_ops *ops, + struct event_trigger_data *data) +{ + data->ref++; + + save_named_trigger(data->named_data->name, data); + + event_hist_trigger_init(ops, data->named_data); + + return 0; +} + +static void event_hist_trigger_named_free(struct event_trigger_ops *ops, + struct event_trigger_data *data) +{ + if (WARN_ON_ONCE(data->ref <= 0)) + return; + + event_hist_trigger_free(ops, data->named_data); + + data->ref--; + if (!data->ref) { + del_named_trigger(data); + trigger_data_free(data); + } +} + +static struct event_trigger_ops event_hist_trigger_named_ops = { + .func = event_hist_trigger, + .print = event_hist_trigger_print, + .init = event_hist_trigger_named_init, + .free = event_hist_trigger_named_free, +}; + +static struct event_trigger_ops *event_hist_get_trigger_ops(char *cmd, + char *param) +{ + return &event_hist_trigger_ops; +} + +static void hist_clear(struct event_trigger_data *data) +{ + struct hist_trigger_data *hist_data = data->private_data; + + if (data->name) + pause_named_trigger(data); + + synchronize_sched(); + + tracing_map_clear(hist_data->map); + + if (data->name) + unpause_named_trigger(data); +} + +static bool compatible_field(struct ftrace_event_field *field, + struct ftrace_event_field *test_field) +{ + if (field == test_field) + return true; + if (field == NULL || test_field == NULL) + return false; + if (strcmp(field->name, test_field->name) != 0) + return false; + if (strcmp(field->type, test_field->type) != 0) + return false; + if (field->size != test_field->size) + return false; + if (field->is_signed != test_field->is_signed) + return false; + + return true; +} + +static bool hist_trigger_match(struct event_trigger_data *data, + struct event_trigger_data *data_test, + struct event_trigger_data *named_data, + bool ignore_filter) +{ + struct tracing_map_sort_key *sort_key, *sort_key_test; + struct hist_trigger_data *hist_data, *hist_data_test; + struct hist_field *key_field, *key_field_test; + unsigned int i; + + if (named_data && (named_data != data_test) && + (named_data != data_test->named_data)) + return false; + + if (!named_data && is_named_trigger(data_test)) + return false; + + hist_data = data->private_data; + hist_data_test = data_test->private_data; + + if (hist_data->n_vals != hist_data_test->n_vals || + hist_data->n_fields != hist_data_test->n_fields || + hist_data->n_sort_keys != hist_data_test->n_sort_keys) + return false; + + if (!ignore_filter) { + if ((data->filter_str && !data_test->filter_str) || + (!data->filter_str && data_test->filter_str)) + return false; + } + + for_each_hist_field(i, hist_data) { + key_field = hist_data->fields[i]; + key_field_test = hist_data_test->fields[i]; + + if (key_field->flags != key_field_test->flags) + return false; + if (!compatible_field(key_field->field, key_field_test->field)) + return false; + if (key_field->offset != key_field_test->offset) + return false; + } + + for (i = 0; i < hist_data->n_sort_keys; i++) { + sort_key = &hist_data->sort_keys[i]; + sort_key_test = &hist_data_test->sort_keys[i]; + + if (sort_key->field_idx != sort_key_test->field_idx || + sort_key->descending != sort_key_test->descending) + return false; + } + + if (!ignore_filter && data->filter_str && + (strcmp(data->filter_str, data_test->filter_str) != 0)) + return false; + + return true; +} + +static int hist_register_trigger(char *glob, struct event_trigger_ops *ops, + struct event_trigger_data *data, + struct trace_event_file *file) +{ + struct hist_trigger_data *hist_data = data->private_data; + struct event_trigger_data *test, *named_data = NULL; + int ret = 0; + + if (hist_data->attrs->name) { + named_data = find_named_trigger(hist_data->attrs->name); + if (named_data) { + if (!hist_trigger_match(data, named_data, named_data, + true)) { + ret = -EINVAL; + goto out; + } + } + } + + if (hist_data->attrs->name && !named_data) + goto new; + + list_for_each_entry_rcu(test, &file->triggers, list) { + if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { + if (!hist_trigger_match(data, test, named_data, false)) + continue; + if (hist_data->attrs->pause) + test->paused = true; + else if (hist_data->attrs->cont) + test->paused = false; + else if (hist_data->attrs->clear) + hist_clear(test); + else + ret = -EEXIST; + goto out; + } + } + new: + if (hist_data->attrs->cont || hist_data->attrs->clear) { + ret = -ENOENT; + goto out; + } + + if (named_data) { + destroy_hist_data(data->private_data); + data->private_data = named_data->private_data; + set_named_trigger_data(data, named_data); + data->ops = &event_hist_trigger_named_ops; + } + + if (hist_data->attrs->pause) + data->paused = true; + + if (data->ops->init) { + ret = data->ops->init(data->ops, data); + if (ret < 0) + goto out; + } + + list_add_rcu(&data->list, &file->triggers); + ret++; + + update_cond_flag(file); + + if (trace_event_trigger_enable_disable(file, 1) < 0) { + list_del_rcu(&data->list); + update_cond_flag(file); + ret--; + } + out: + return ret; +} + +static void hist_unregister_trigger(char *glob, struct event_trigger_ops *ops, + struct event_trigger_data *data, + struct trace_event_file *file) +{ + struct hist_trigger_data *hist_data = data->private_data; + struct event_trigger_data *test, *named_data = NULL; + bool unregistered = false; + + if (hist_data->attrs->name) + named_data = find_named_trigger(hist_data->attrs->name); + + list_for_each_entry_rcu(test, &file->triggers, list) { + if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { + if (!hist_trigger_match(data, test, named_data, false)) + continue; + unregistered = true; + list_del_rcu(&test->list); + trace_event_trigger_enable_disable(file, 0); + update_cond_flag(file); + break; + } + } + + if (unregistered && test->ops->free) + test->ops->free(test->ops, test); +} + +static void hist_unreg_all(struct trace_event_file *file) +{ + struct event_trigger_data *test; + + list_for_each_entry_rcu(test, &file->triggers, list) { + if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { + list_del_rcu(&test->list); + trace_event_trigger_enable_disable(file, 0); + update_cond_flag(file); + if (test->ops->free) + test->ops->free(test->ops, test); + } + } +} + +static int event_hist_trigger_func(struct event_command *cmd_ops, + struct trace_event_file *file, + char *glob, char *cmd, char *param) +{ + unsigned int hist_trigger_bits = TRACING_MAP_BITS_DEFAULT; + struct event_trigger_data *trigger_data; + struct hist_trigger_attrs *attrs; + struct event_trigger_ops *trigger_ops; + struct hist_trigger_data *hist_data; + char *trigger; + int ret = 0; + + if (!param) + return -EINVAL; + + /* separate the trigger from the filter (k:v [if filter]) */ + trigger = strsep(¶m, " \t"); + if (!trigger) + return -EINVAL; + + attrs = parse_hist_trigger_attrs(trigger); + if (IS_ERR(attrs)) + return PTR_ERR(attrs); + + if (attrs->map_bits) + hist_trigger_bits = attrs->map_bits; + + hist_data = create_hist_data(hist_trigger_bits, attrs, file); + if (IS_ERR(hist_data)) { + destroy_hist_trigger_attrs(attrs); + return PTR_ERR(hist_data); + } + + trigger_ops = cmd_ops->get_trigger_ops(cmd, trigger); + + ret = -ENOMEM; + trigger_data = kzalloc(sizeof(*trigger_data), GFP_KERNEL); + if (!trigger_data) + goto out_free; + + trigger_data->count = -1; + trigger_data->ops = trigger_ops; + trigger_data->cmd_ops = cmd_ops; + + INIT_LIST_HEAD(&trigger_data->list); + RCU_INIT_POINTER(trigger_data->filter, NULL); + + trigger_data->private_data = hist_data; + + /* if param is non-empty, it's supposed to be a filter */ + if (param && cmd_ops->set_filter) { + ret = cmd_ops->set_filter(param, trigger_data, file); + if (ret < 0) + goto out_free; + } + + if (glob[0] == '!') { + cmd_ops->unreg(glob+1, trigger_ops, trigger_data, file); + ret = 0; + goto out_free; + } + + ret = cmd_ops->reg(glob, trigger_ops, trigger_data, file); + /* + * The above returns on success the # of triggers registered, + * but if it didn't register any it returns zero. Consider no + * triggers registered a failure too. + */ + if (!ret) { + if (!(attrs->pause || attrs->cont || attrs->clear)) + ret = -ENOENT; + goto out_free; + } else if (ret < 0) + goto out_free; + /* Just return zero, not the number of registered triggers */ + ret = 0; + out: + return ret; + out_free: + if (cmd_ops->set_filter) + cmd_ops->set_filter(NULL, trigger_data, NULL); + + kfree(trigger_data); + + destroy_hist_data(hist_data); + goto out; +} + +static struct event_command trigger_hist_cmd = { + .name = "hist", + .trigger_type = ETT_EVENT_HIST, + .flags = EVENT_CMD_FL_NEEDS_REC, + .func = event_hist_trigger_func, + .reg = hist_register_trigger, + .unreg = hist_unregister_trigger, + .unreg_all = hist_unreg_all, + .get_trigger_ops = event_hist_get_trigger_ops, + .set_filter = set_trigger_filter, +}; + +__init int register_trigger_hist_cmd(void) +{ + int ret; + + ret = register_event_command(&trigger_hist_cmd); + WARN_ON(ret < 0); + + return ret; +} + +static void +hist_enable_trigger(struct event_trigger_data *data, void *rec) +{ + struct enable_trigger_data *enable_data = data->private_data; + struct event_trigger_data *test; + + list_for_each_entry_rcu(test, &enable_data->file->triggers, list) { + if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { + if (enable_data->enable) + test->paused = false; + else + test->paused = true; + } + } +} + +static void +hist_enable_count_trigger(struct event_trigger_data *data, void *rec) +{ + if (!data->count) + return; + + if (data->count != -1) + (data->count)--; + + hist_enable_trigger(data, rec); +} + +static struct event_trigger_ops hist_enable_trigger_ops = { + .func = hist_enable_trigger, + .print = event_enable_trigger_print, + .init = event_trigger_init, + .free = event_enable_trigger_free, +}; + +static struct event_trigger_ops hist_enable_count_trigger_ops = { + .func = hist_enable_count_trigger, + .print = event_enable_trigger_print, + .init = event_trigger_init, + .free = event_enable_trigger_free, +}; + +static struct event_trigger_ops hist_disable_trigger_ops = { + .func = hist_enable_trigger, + .print = event_enable_trigger_print, + .init = event_trigger_init, + .free = event_enable_trigger_free, +}; + +static struct event_trigger_ops hist_disable_count_trigger_ops = { + .func = hist_enable_count_trigger, + .print = event_enable_trigger_print, + .init = event_trigger_init, + .free = event_enable_trigger_free, +}; + +static struct event_trigger_ops * +hist_enable_get_trigger_ops(char *cmd, char *param) +{ + struct event_trigger_ops *ops; + bool enable; + + enable = (strcmp(cmd, ENABLE_HIST_STR) == 0); + + if (enable) + ops = param ? &hist_enable_count_trigger_ops : + &hist_enable_trigger_ops; + else + ops = param ? &hist_disable_count_trigger_ops : + &hist_disable_trigger_ops; + + return ops; +} + +static void hist_enable_unreg_all(struct trace_event_file *file) +{ + struct event_trigger_data *test; + + list_for_each_entry_rcu(test, &file->triggers, list) { + if (test->cmd_ops->trigger_type == ETT_HIST_ENABLE) { + list_del_rcu(&test->list); + update_cond_flag(file); + trace_event_trigger_enable_disable(file, 0); + if (test->ops->free) + test->ops->free(test->ops, test); + } + } +} + +static struct event_command trigger_hist_enable_cmd = { + .name = ENABLE_HIST_STR, + .trigger_type = ETT_HIST_ENABLE, + .func = event_enable_trigger_func, + .reg = event_enable_register_trigger, + .unreg = event_enable_unregister_trigger, + .unreg_all = hist_enable_unreg_all, + .get_trigger_ops = hist_enable_get_trigger_ops, + .set_filter = set_trigger_filter, +}; + +static struct event_command trigger_hist_disable_cmd = { + .name = DISABLE_HIST_STR, + .trigger_type = ETT_HIST_ENABLE, + .func = event_enable_trigger_func, + .reg = event_enable_register_trigger, + .unreg = event_enable_unregister_trigger, + .unreg_all = hist_enable_unreg_all, + .get_trigger_ops = hist_enable_get_trigger_ops, + .set_filter = set_trigger_filter, +}; + +static __init void unregister_trigger_hist_enable_disable_cmds(void) +{ + unregister_event_command(&trigger_hist_enable_cmd); + unregister_event_command(&trigger_hist_disable_cmd); +} + +__init int register_trigger_hist_enable_disable_cmds(void) +{ + int ret; + + ret = register_event_command(&trigger_hist_enable_cmd); + if (WARN_ON(ret < 0)) + return ret; + ret = register_event_command(&trigger_hist_disable_cmd); + if (WARN_ON(ret < 0)) + unregister_trigger_hist_enable_disable_cmds(); + + return ret; +} diff --git a/kernel/trace/trace_events_trigger.c b/kernel/trace/trace_events_trigger.c index d67992f3bb0e..a975571cde24 100644 --- a/kernel/trace/trace_events_trigger.c +++ b/kernel/trace/trace_events_trigger.c @@ -347,7 +347,7 @@ __init int register_event_command(struct event_command *cmd) * Currently we only unregister event commands from __init, so mark * this __init too. */ -static __init int unregister_event_command(struct event_command *cmd) +__init int unregister_event_command(struct event_command *cmd) { struct event_command *p, *n; int ret = -ENODEV; @@ -641,6 +641,7 @@ event_trigger_callback(struct event_command *cmd_ops, trigger_data->ops = trigger_ops; trigger_data->cmd_ops = cmd_ops; INIT_LIST_HEAD(&trigger_data->list); + INIT_LIST_HEAD(&trigger_data->named_list); if (glob[0] == '!') { cmd_ops->unreg(glob+1, trigger_ops, trigger_data, file); @@ -764,6 +765,148 @@ int set_trigger_filter(char *filter_str, return ret; } +static LIST_HEAD(named_triggers); + +/** + * find_named_trigger - Find the common named trigger associated with @name + * @name: The name of the set of named triggers to find the common data for + * + * Named triggers are sets of triggers that share a common set of + * trigger data. The first named trigger registered with a given name + * owns the common trigger data that the others subsequently + * registered with the same name will reference. This function + * returns the common trigger data associated with that first + * registered instance. + * + * Return: the common trigger data for the given named trigger on + * success, NULL otherwise. + */ +struct event_trigger_data *find_named_trigger(const char *name) +{ + struct event_trigger_data *data; + + if (!name) + return NULL; + + list_for_each_entry(data, &named_triggers, named_list) { + if (data->named_data) + continue; + if (strcmp(data->name, name) == 0) + return data; + } + + return NULL; +} + +/** + * is_named_trigger - determine if a given trigger is a named trigger + * @test: The trigger data to test + * + * Return: true if 'test' is a named trigger, false otherwise. + */ +bool is_named_trigger(struct event_trigger_data *test) +{ + struct event_trigger_data *data; + + list_for_each_entry(data, &named_triggers, named_list) { + if (test == data) + return true; + } + + return false; +} + +/** + * save_named_trigger - save the trigger in the named trigger list + * @name: The name of the named trigger set + * @data: The trigger data to save + * + * Return: 0 if successful, negative error otherwise. + */ +int save_named_trigger(const char *name, struct event_trigger_data *data) +{ + data->name = kstrdup(name, GFP_KERNEL); + if (!data->name) + return -ENOMEM; + + list_add(&data->named_list, &named_triggers); + + return 0; +} + +/** + * del_named_trigger - delete a trigger from the named trigger list + * @data: The trigger data to delete + */ +void del_named_trigger(struct event_trigger_data *data) +{ + kfree(data->name); + data->name = NULL; + + list_del(&data->named_list); +} + +static void __pause_named_trigger(struct event_trigger_data *data, bool pause) +{ + struct event_trigger_data *test; + + list_for_each_entry(test, &named_triggers, named_list) { + if (strcmp(test->name, data->name) == 0) { + if (pause) { + test->paused_tmp = test->paused; + test->paused = true; + } else { + test->paused = test->paused_tmp; + } + } + } +} + +/** + * pause_named_trigger - Pause all named triggers with the same name + * @data: The trigger data of a named trigger to pause + * + * Pauses a named trigger along with all other triggers having the + * same name. Because named triggers share a common set of data, + * pausing only one is meaningless, so pausing one named trigger needs + * to pause all triggers with the same name. + */ +void pause_named_trigger(struct event_trigger_data *data) +{ + __pause_named_trigger(data, true); +} + +/** + * unpause_named_trigger - Un-pause all named triggers with the same name + * @data: The trigger data of a named trigger to unpause + * + * Un-pauses a named trigger along with all other triggers having the + * same name. Because named triggers share a common set of data, + * unpausing only one is meaningless, so unpausing one named trigger + * needs to unpause all triggers with the same name. + */ +void unpause_named_trigger(struct event_trigger_data *data) +{ + __pause_named_trigger(data, false); +} + +/** + * set_named_trigger_data - Associate common named trigger data + * @data: The trigger data of a named trigger to unpause + * + * Named triggers are sets of triggers that share a common set of + * trigger data. The first named trigger registered with a given name + * owns the common trigger data that the others subsequently + * registered with the same name will reference. This function + * associates the common trigger data from the first trigger with the + * given trigger. + */ +void set_named_trigger_data(struct event_trigger_data *data, + struct event_trigger_data *named_data) +{ + data->named_data = named_data; +} + static void traceon_trigger(struct event_trigger_data *data, void *rec) { @@ -1062,15 +1205,6 @@ static __init void unregister_trigger_traceon_traceoff_cmds(void) unregister_event_command(&trigger_traceoff_cmd); } -/* Avoid typos */ -#define ENABLE_EVENT_STR "enable_event" -#define DISABLE_EVENT_STR "disable_event" - -struct enable_trigger_data { - struct trace_event_file *file; - bool enable; -}; - static void event_enable_trigger(struct event_trigger_data *data, void *rec) { @@ -1100,14 +1234,16 @@ event_enable_count_trigger(struct event_trigger_data *data, void *rec) event_enable_trigger(data, rec); } -static int -event_enable_trigger_print(struct seq_file *m, struct event_trigger_ops *ops, - struct event_trigger_data *data) +int event_enable_trigger_print(struct seq_file *m, + struct event_trigger_ops *ops, + struct event_trigger_data *data) { struct enable_trigger_data *enable_data = data->private_data; seq_printf(m, "%s:%s:%s", - enable_data->enable ? ENABLE_EVENT_STR : DISABLE_EVENT_STR, + enable_data->hist ? + (enable_data->enable ? ENABLE_HIST_STR : DISABLE_HIST_STR) : + (enable_data->enable ? ENABLE_EVENT_STR : DISABLE_EVENT_STR), enable_data->file->event_call->class->system, trace_event_name(enable_data->file->event_call)); @@ -1124,9 +1260,8 @@ event_enable_trigger_print(struct seq_file *m, struct event_trigger_ops *ops, return 0; } -static void -event_enable_trigger_free(struct event_trigger_ops *ops, - struct event_trigger_data *data) +void event_enable_trigger_free(struct event_trigger_ops *ops, + struct event_trigger_data *data) { struct enable_trigger_data *enable_data = data->private_data; @@ -1171,10 +1306,9 @@ static struct event_trigger_ops event_disable_count_trigger_ops = { .free = event_enable_trigger_free, }; -static int -event_enable_trigger_func(struct event_command *cmd_ops, - struct trace_event_file *file, - char *glob, char *cmd, char *param) +int event_enable_trigger_func(struct event_command *cmd_ops, + struct trace_event_file *file, + char *glob, char *cmd, char *param) { struct trace_event_file *event_enable_file; struct enable_trigger_data *enable_data; @@ -1183,6 +1317,7 @@ event_enable_trigger_func(struct event_command *cmd_ops, struct trace_array *tr = file->tr; const char *system; const char *event; + bool hist = false; char *trigger; char *number; bool enable; @@ -1207,8 +1342,15 @@ event_enable_trigger_func(struct event_command *cmd_ops, if (!event_enable_file) goto out; - enable = strcmp(cmd, ENABLE_EVENT_STR) == 0; +#ifdef CONFIG_HIST_TRIGGERS + hist = ((strcmp(cmd, ENABLE_HIST_STR) == 0) || + (strcmp(cmd, DISABLE_HIST_STR) == 0)); + enable = ((strcmp(cmd, ENABLE_EVENT_STR) == 0) || + (strcmp(cmd, ENABLE_HIST_STR) == 0)); +#else + enable = strcmp(cmd, ENABLE_EVENT_STR) == 0; +#endif trigger_ops = cmd_ops->get_trigger_ops(cmd, trigger); ret = -ENOMEM; @@ -1228,6 +1370,7 @@ event_enable_trigger_func(struct event_command *cmd_ops, INIT_LIST_HEAD(&trigger_data->list); RCU_INIT_POINTER(trigger_data->filter, NULL); + enable_data->hist = hist; enable_data->enable = enable; enable_data->file = event_enable_file; trigger_data->private_data = enable_data; @@ -1305,10 +1448,10 @@ event_enable_trigger_func(struct event_command *cmd_ops, goto out; } -static int event_enable_register_trigger(char *glob, - struct event_trigger_ops *ops, - struct event_trigger_data *data, - struct trace_event_file *file) +int event_enable_register_trigger(char *glob, + struct event_trigger_ops *ops, + struct event_trigger_data *data, + struct trace_event_file *file) { struct enable_trigger_data *enable_data = data->private_data; struct enable_trigger_data *test_enable_data; @@ -1318,6 +1461,8 @@ static int event_enable_register_trigger(char *glob, list_for_each_entry_rcu(test, &file->triggers, list) { test_enable_data = test->private_data; if (test_enable_data && + (test->cmd_ops->trigger_type == + data->cmd_ops->trigger_type) && (test_enable_data->file == enable_data->file)) { ret = -EEXIST; goto out; @@ -1343,10 +1488,10 @@ out: return ret; } -static void event_enable_unregister_trigger(char *glob, - struct event_trigger_ops *ops, - struct event_trigger_data *test, - struct trace_event_file *file) +void event_enable_unregister_trigger(char *glob, + struct event_trigger_ops *ops, + struct event_trigger_data *test, + struct trace_event_file *file) { struct enable_trigger_data *test_enable_data = test->private_data; struct enable_trigger_data *enable_data; @@ -1356,6 +1501,8 @@ static void event_enable_unregister_trigger(char *glob, list_for_each_entry_rcu(data, &file->triggers, list) { enable_data = data->private_data; if (enable_data && + (data->cmd_ops->trigger_type == + test->cmd_ops->trigger_type) && (enable_data->file == test_enable_data->file)) { unregistered = true; list_del_rcu(&data->list); @@ -1375,8 +1522,12 @@ event_enable_get_trigger_ops(char *cmd, char *param) struct event_trigger_ops *ops; bool enable; +#ifdef CONFIG_HIST_TRIGGERS + enable = ((strcmp(cmd, ENABLE_EVENT_STR) == 0) || + (strcmp(cmd, ENABLE_HIST_STR) == 0)); +#else enable = strcmp(cmd, ENABLE_EVENT_STR) == 0; - +#endif if (enable) ops = param ? &event_enable_count_trigger_ops : &event_enable_trigger_ops; @@ -1447,6 +1598,8 @@ __init int register_trigger_cmds(void) register_trigger_snapshot_cmd(); register_trigger_stacktrace_cmd(); register_trigger_enable_disable_cmds(); + register_trigger_hist_enable_disable_cmds(); + register_trigger_hist_cmd(); return 0; } diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c index 919e0ddd8fcc..5546eec0505f 100644 --- a/kernel/trace/trace_kprobe.c +++ b/kernel/trace/trace_kprobe.c @@ -1149,14 +1149,15 @@ kprobe_perf_func(struct trace_kprobe *tk, struct pt_regs *regs) size = ALIGN(__size + sizeof(u32), sizeof(u64)); size -= sizeof(u32); - entry = perf_trace_buf_prepare(size, call->event.type, NULL, &rctx); + entry = perf_trace_buf_alloc(size, NULL, &rctx); if (!entry) return; entry->ip = (unsigned long)tk->rp.kp.addr; memset(&entry[1], 0, dsize); store_trace_args(sizeof(*entry), &tk->tp, regs, (u8 *)&entry[1], dsize); - perf_trace_buf_submit(entry, size, rctx, 0, 1, regs, head, NULL); + perf_trace_buf_submit(entry, size, rctx, call->event.type, 1, regs, + head, NULL); } NOKPROBE_SYMBOL(kprobe_perf_func); @@ -1184,14 +1185,15 @@ kretprobe_perf_func(struct trace_kprobe *tk, struct kretprobe_instance *ri, size = ALIGN(__size + sizeof(u32), sizeof(u64)); size -= sizeof(u32); - entry = perf_trace_buf_prepare(size, call->event.type, NULL, &rctx); + entry = perf_trace_buf_alloc(size, NULL, &rctx); if (!entry) return; entry->func = (unsigned long)tk->rp.kp.addr; entry->ret_ip = (unsigned long)ri->ret_addr; store_trace_args(sizeof(*entry), &tk->tp, regs, (u8 *)&entry[1], dsize); - perf_trace_buf_submit(entry, size, rctx, 0, 1, regs, head, NULL); + perf_trace_buf_submit(entry, size, rctx, call->event.type, 1, regs, + head, NULL); } NOKPROBE_SYMBOL(kretprobe_perf_func); #endif /* CONFIG_PERF_EVENTS */ diff --git a/kernel/trace/trace_syscalls.c b/kernel/trace/trace_syscalls.c index e78f364cc192..b2b6efc083a4 100644 --- a/kernel/trace/trace_syscalls.c +++ b/kernel/trace/trace_syscalls.c @@ -587,15 +587,16 @@ static void perf_syscall_enter(void *ignore, struct pt_regs *regs, long id) size = ALIGN(size + sizeof(u32), sizeof(u64)); size -= sizeof(u32); - rec = (struct syscall_trace_enter *)perf_trace_buf_prepare(size, - sys_data->enter_event->event.type, NULL, &rctx); + rec = perf_trace_buf_alloc(size, NULL, &rctx); if (!rec) return; rec->nr = syscall_nr; syscall_get_arguments(current, regs, 0, sys_data->nb_args, (unsigned long *)&rec->args); - perf_trace_buf_submit(rec, size, rctx, 0, 1, regs, head, NULL); + perf_trace_buf_submit(rec, size, rctx, + sys_data->enter_event->event.type, 1, regs, + head, NULL); } static int perf_sysenter_enable(struct trace_event_call *call) @@ -660,14 +661,14 @@ static void perf_syscall_exit(void *ignore, struct pt_regs *regs, long ret) size = ALIGN(sizeof(*rec) + sizeof(u32), sizeof(u64)); size -= sizeof(u32); - rec = (struct syscall_trace_exit *)perf_trace_buf_prepare(size, - sys_data->exit_event->event.type, NULL, &rctx); + rec = perf_trace_buf_alloc(size, NULL, &rctx); if (!rec) return; rec->nr = syscall_nr; rec->ret = syscall_get_return_value(current, regs); - perf_trace_buf_submit(rec, size, rctx, 0, 1, regs, head, NULL); + perf_trace_buf_submit(rec, size, rctx, sys_data->exit_event->event.type, + 1, regs, head, NULL); } static int perf_sysexit_enable(struct trace_event_call *call) diff --git a/kernel/trace/trace_uprobe.c b/kernel/trace/trace_uprobe.c index 7915142c89e4..c53485441c88 100644 --- a/kernel/trace/trace_uprobe.c +++ b/kernel/trace/trace_uprobe.c @@ -1131,7 +1131,7 @@ static void __uprobe_perf_func(struct trace_uprobe *tu, if (hlist_empty(head)) goto out; - entry = perf_trace_buf_prepare(size, call->event.type, NULL, &rctx); + entry = perf_trace_buf_alloc(size, NULL, &rctx); if (!entry) goto out; @@ -1152,7 +1152,8 @@ static void __uprobe_perf_func(struct trace_uprobe *tu, memset(data + len, 0, size - esize - len); } - perf_trace_buf_submit(entry, size, rctx, 0, 1, regs, head, NULL); + perf_trace_buf_submit(entry, size, rctx, call->event.type, 1, regs, + head, NULL); out: preempt_enable(); } diff --git a/kernel/trace/tracing_map.c b/kernel/trace/tracing_map.c new file mode 100644 index 000000000000..0a689bbb78ef --- /dev/null +++ b/kernel/trace/tracing_map.c @@ -0,0 +1,1062 @@ +/* + * tracing_map - lock-free map for tracing + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * Copyright (C) 2015 Tom Zanussi <tom.zanussi@linux.intel.com> + * + * tracing_map implementation inspired by lock-free map algorithms + * originated by Dr. Cliff Click: + * + * http://www.azulsystems.com/blog/cliff/2007-03-26-non-blocking-hashtable + * http://www.azulsystems.com/events/javaone_2007/2007_LockFreeHash.pdf + */ + +#include <linux/vmalloc.h> +#include <linux/jhash.h> +#include <linux/slab.h> +#include <linux/sort.h> + +#include "tracing_map.h" +#include "trace.h" + +/* + * NOTE: For a detailed description of the data structures used by + * these functions (such as tracing_map_elt) please see the overview + * of tracing_map data structures at the beginning of tracing_map.h. + */ + +/** + * tracing_map_update_sum - Add a value to a tracing_map_elt's sum field + * @elt: The tracing_map_elt + * @i: The index of the given sum associated with the tracing_map_elt + * @n: The value to add to the sum + * + * Add n to sum i associated with the specified tracing_map_elt + * instance. The index i is the index returned by the call to + * tracing_map_add_sum_field() when the tracing map was set up. + */ +void tracing_map_update_sum(struct tracing_map_elt *elt, unsigned int i, u64 n) +{ + atomic64_add(n, &elt->fields[i].sum); +} + +/** + * tracing_map_read_sum - Return the value of a tracing_map_elt's sum field + * @elt: The tracing_map_elt + * @i: The index of the given sum associated with the tracing_map_elt + * + * Retrieve the value of the sum i associated with the specified + * tracing_map_elt instance. The index i is the index returned by the + * call to tracing_map_add_sum_field() when the tracing map was set + * up. + * + * Return: The sum associated with field i for elt. + */ +u64 tracing_map_read_sum(struct tracing_map_elt *elt, unsigned int i) +{ + return (u64)atomic64_read(&elt->fields[i].sum); +} + +int tracing_map_cmp_string(void *val_a, void *val_b) +{ + char *a = val_a; + char *b = val_b; + + return strcmp(a, b); +} + +int tracing_map_cmp_none(void *val_a, void *val_b) +{ + return 0; +} + +static int tracing_map_cmp_atomic64(void *val_a, void *val_b) +{ + u64 a = atomic64_read((atomic64_t *)val_a); + u64 b = atomic64_read((atomic64_t *)val_b); + + return (a > b) ? 1 : ((a < b) ? -1 : 0); +} + +#define DEFINE_TRACING_MAP_CMP_FN(type) \ +static int tracing_map_cmp_##type(void *val_a, void *val_b) \ +{ \ + type a = *(type *)val_a; \ + type b = *(type *)val_b; \ + \ + return (a > b) ? 1 : ((a < b) ? -1 : 0); \ +} + +DEFINE_TRACING_MAP_CMP_FN(s64); +DEFINE_TRACING_MAP_CMP_FN(u64); +DEFINE_TRACING_MAP_CMP_FN(s32); +DEFINE_TRACING_MAP_CMP_FN(u32); +DEFINE_TRACING_MAP_CMP_FN(s16); +DEFINE_TRACING_MAP_CMP_FN(u16); +DEFINE_TRACING_MAP_CMP_FN(s8); +DEFINE_TRACING_MAP_CMP_FN(u8); + +tracing_map_cmp_fn_t tracing_map_cmp_num(int field_size, + int field_is_signed) +{ + tracing_map_cmp_fn_t fn = tracing_map_cmp_none; + + switch (field_size) { + case 8: + if (field_is_signed) + fn = tracing_map_cmp_s64; + else + fn = tracing_map_cmp_u64; + break; + case 4: + if (field_is_signed) + fn = tracing_map_cmp_s32; + else + fn = tracing_map_cmp_u32; + break; + case 2: + if (field_is_signed) + fn = tracing_map_cmp_s16; + else + fn = tracing_map_cmp_u16; + break; + case 1: + if (field_is_signed) + fn = tracing_map_cmp_s8; + else + fn = tracing_map_cmp_u8; + break; + } + + return fn; +} + +static int tracing_map_add_field(struct tracing_map *map, + tracing_map_cmp_fn_t cmp_fn) +{ + int ret = -EINVAL; + + if (map->n_fields < TRACING_MAP_FIELDS_MAX) { + ret = map->n_fields; + map->fields[map->n_fields++].cmp_fn = cmp_fn; + } + + return ret; +} + +/** + * tracing_map_add_sum_field - Add a field describing a tracing_map sum + * @map: The tracing_map + * + * Add a sum field to the key and return the index identifying it in + * the map and associated tracing_map_elts. This is the index used + * for instance to update a sum for a particular tracing_map_elt using + * tracing_map_update_sum() or reading it via tracing_map_read_sum(). + * + * Return: The index identifying the field in the map and associated + * tracing_map_elts, or -EINVAL on error. + */ +int tracing_map_add_sum_field(struct tracing_map *map) +{ + return tracing_map_add_field(map, tracing_map_cmp_atomic64); +} + +/** + * tracing_map_add_key_field - Add a field describing a tracing_map key + * @map: The tracing_map + * @offset: The offset within the key + * @cmp_fn: The comparison function that will be used to sort on the key + * + * Let the map know there is a key and that if it's used as a sort key + * to use cmp_fn. + * + * A key can be a subset of a compound key; for that purpose, the + * offset param is used to describe where within the the compound key + * the key referenced by this key field resides. + * + * Return: The index identifying the field in the map and associated + * tracing_map_elts, or -EINVAL on error. + */ +int tracing_map_add_key_field(struct tracing_map *map, + unsigned int offset, + tracing_map_cmp_fn_t cmp_fn) + +{ + int idx = tracing_map_add_field(map, cmp_fn); + + if (idx < 0) + return idx; + + map->fields[idx].offset = offset; + + map->key_idx[map->n_keys++] = idx; + + return idx; +} + +void tracing_map_array_clear(struct tracing_map_array *a) +{ + unsigned int i; + + if (!a->pages) + return; + + for (i = 0; i < a->n_pages; i++) + memset(a->pages[i], 0, PAGE_SIZE); +} + +void tracing_map_array_free(struct tracing_map_array *a) +{ + unsigned int i; + + if (!a) + return; + + if (!a->pages) { + kfree(a); + return; + } + + for (i = 0; i < a->n_pages; i++) { + if (!a->pages[i]) + break; + free_page((unsigned long)a->pages[i]); + } +} + +struct tracing_map_array *tracing_map_array_alloc(unsigned int n_elts, + unsigned int entry_size) +{ + struct tracing_map_array *a; + unsigned int i; + + a = kzalloc(sizeof(*a), GFP_KERNEL); + if (!a) + return NULL; + + a->entry_size_shift = fls(roundup_pow_of_two(entry_size) - 1); + a->entries_per_page = PAGE_SIZE / (1 << a->entry_size_shift); + a->n_pages = n_elts / a->entries_per_page; + if (!a->n_pages) + a->n_pages = 1; + a->entry_shift = fls(a->entries_per_page) - 1; + a->entry_mask = (1 << a->entry_shift) - 1; + + a->pages = kcalloc(a->n_pages, sizeof(void *), GFP_KERNEL); + if (!a->pages) + goto free; + + for (i = 0; i < a->n_pages; i++) { + a->pages[i] = (void *)get_zeroed_page(GFP_KERNEL); + if (!a->pages[i]) + goto free; + } + out: + return a; + free: + tracing_map_array_free(a); + a = NULL; + + goto out; +} + +static void tracing_map_elt_clear(struct tracing_map_elt *elt) +{ + unsigned i; + + for (i = 0; i < elt->map->n_fields; i++) + if (elt->fields[i].cmp_fn == tracing_map_cmp_atomic64) + atomic64_set(&elt->fields[i].sum, 0); + + if (elt->map->ops && elt->map->ops->elt_clear) + elt->map->ops->elt_clear(elt); +} + +static void tracing_map_elt_init_fields(struct tracing_map_elt *elt) +{ + unsigned int i; + + tracing_map_elt_clear(elt); + + for (i = 0; i < elt->map->n_fields; i++) { + elt->fields[i].cmp_fn = elt->map->fields[i].cmp_fn; + + if (elt->fields[i].cmp_fn != tracing_map_cmp_atomic64) + elt->fields[i].offset = elt->map->fields[i].offset; + } +} + +static void tracing_map_elt_free(struct tracing_map_elt *elt) +{ + if (!elt) + return; + + if (elt->map->ops && elt->map->ops->elt_free) + elt->map->ops->elt_free(elt); + kfree(elt->fields); + kfree(elt->key); + kfree(elt); +} + +static struct tracing_map_elt *tracing_map_elt_alloc(struct tracing_map *map) +{ + struct tracing_map_elt *elt; + int err = 0; + + elt = kzalloc(sizeof(*elt), GFP_KERNEL); + if (!elt) + return ERR_PTR(-ENOMEM); + + elt->map = map; + + elt->key = kzalloc(map->key_size, GFP_KERNEL); + if (!elt->key) { + err = -ENOMEM; + goto free; + } + + elt->fields = kcalloc(map->n_fields, sizeof(*elt->fields), GFP_KERNEL); + if (!elt->fields) { + err = -ENOMEM; + goto free; + } + + tracing_map_elt_init_fields(elt); + + if (map->ops && map->ops->elt_alloc) { + err = map->ops->elt_alloc(elt); + if (err) + goto free; + } + return elt; + free: + tracing_map_elt_free(elt); + + return ERR_PTR(err); +} + +static struct tracing_map_elt *get_free_elt(struct tracing_map *map) +{ + struct tracing_map_elt *elt = NULL; + int idx; + + idx = atomic_inc_return(&map->next_elt); + if (idx < map->max_elts) { + elt = *(TRACING_MAP_ELT(map->elts, idx)); + if (map->ops && map->ops->elt_init) + map->ops->elt_init(elt); + } + + return elt; +} + +static void tracing_map_free_elts(struct tracing_map *map) +{ + unsigned int i; + + if (!map->elts) + return; + + for (i = 0; i < map->max_elts; i++) { + tracing_map_elt_free(*(TRACING_MAP_ELT(map->elts, i))); + *(TRACING_MAP_ELT(map->elts, i)) = NULL; + } + + tracing_map_array_free(map->elts); + map->elts = NULL; +} + +static int tracing_map_alloc_elts(struct tracing_map *map) +{ + unsigned int i; + + map->elts = tracing_map_array_alloc(map->max_elts, + sizeof(struct tracing_map_elt *)); + if (!map->elts) + return -ENOMEM; + + for (i = 0; i < map->max_elts; i++) { + *(TRACING_MAP_ELT(map->elts, i)) = tracing_map_elt_alloc(map); + if (IS_ERR(*(TRACING_MAP_ELT(map->elts, i)))) { + *(TRACING_MAP_ELT(map->elts, i)) = NULL; + tracing_map_free_elts(map); + + return -ENOMEM; + } + } + + return 0; +} + +static inline bool keys_match(void *key, void *test_key, unsigned key_size) +{ + bool match = true; + + if (memcmp(key, test_key, key_size)) + match = false; + + return match; +} + +static inline struct tracing_map_elt * +__tracing_map_insert(struct tracing_map *map, void *key, bool lookup_only) +{ + u32 idx, key_hash, test_key; + struct tracing_map_entry *entry; + + key_hash = jhash(key, map->key_size, 0); + if (key_hash == 0) + key_hash = 1; + idx = key_hash >> (32 - (map->map_bits + 1)); + + while (1) { + idx &= (map->map_size - 1); + entry = TRACING_MAP_ENTRY(map->map, idx); + test_key = entry->key; + + if (test_key && test_key == key_hash && entry->val && + keys_match(key, entry->val->key, map->key_size)) { + atomic64_inc(&map->hits); + return entry->val; + } + + if (!test_key) { + if (lookup_only) + break; + + if (!cmpxchg(&entry->key, 0, key_hash)) { + struct tracing_map_elt *elt; + + elt = get_free_elt(map); + if (!elt) { + atomic64_inc(&map->drops); + entry->key = 0; + break; + } + + memcpy(elt->key, key, map->key_size); + entry->val = elt; + atomic64_inc(&map->hits); + + return entry->val; + } + } + + idx++; + } + + return NULL; +} + +/** + * tracing_map_insert - Insert key and/or retrieve val from a tracing_map + * @map: The tracing_map to insert into + * @key: The key to insert + * + * Inserts a key into a tracing_map and creates and returns a new + * tracing_map_elt for it, or if the key has already been inserted by + * a previous call, returns the tracing_map_elt already associated + * with it. When the map was created, the number of elements to be + * allocated for the map was specified (internally maintained as + * 'max_elts' in struct tracing_map), and that number of + * tracing_map_elts was created by tracing_map_init(). This is the + * pre-allocated pool of tracing_map_elts that tracing_map_insert() + * will allocate from when adding new keys. Once that pool is + * exhausted, tracing_map_insert() is useless and will return NULL to + * signal that state. There are two user-visible tracing_map + * variables, 'hits' and 'drops', which are updated by this function. + * Every time an element is either successfully inserted or retrieved, + * the 'hits' value is incrememented. Every time an element insertion + * fails, the 'drops' value is incremented. + * + * This is a lock-free tracing map insertion function implementing a + * modified form of Cliff Click's basic insertion algorithm. It + * requires the table size be a power of two. To prevent any + * possibility of an infinite loop we always make the internal table + * size double the size of the requested table size (max_elts * 2). + * Likewise, we never reuse a slot or resize or delete elements - when + * we've reached max_elts entries, we simply return NULL once we've + * run out of entries. Readers can at any point in time traverse the + * tracing map and safely access the key/val pairs. + * + * Return: the tracing_map_elt pointer val associated with the key. + * If this was a newly inserted key, the val will be a newly allocated + * and associated tracing_map_elt pointer val. If the key wasn't + * found and the pool of tracing_map_elts has been exhausted, NULL is + * returned and no further insertions will succeed. + */ +struct tracing_map_elt *tracing_map_insert(struct tracing_map *map, void *key) +{ + return __tracing_map_insert(map, key, false); +} + +/** + * tracing_map_lookup - Retrieve val from a tracing_map + * @map: The tracing_map to perform the lookup on + * @key: The key to look up + * + * Looks up key in tracing_map and if found returns the matching + * tracing_map_elt. This is a lock-free lookup; see + * tracing_map_insert() for details on tracing_map and how it works. + * Every time an element is retrieved, the 'hits' value is + * incrememented. There is one user-visible tracing_map variable, + * 'hits', which is updated by this function. Every time an element + * is successfully retrieved, the 'hits' value is incrememented. The + * 'drops' value is never updated by this function. + * + * Return: the tracing_map_elt pointer val associated with the key. + * If the key wasn't found, NULL is returned. + */ +struct tracing_map_elt *tracing_map_lookup(struct tracing_map *map, void *key) +{ + return __tracing_map_insert(map, key, true); +} + +/** + * tracing_map_destroy - Destroy a tracing_map + * @map: The tracing_map to destroy + * + * Frees a tracing_map along with its associated array of + * tracing_map_elts. + * + * Callers should make sure there are no readers or writers actively + * reading or inserting into the map before calling this. + */ +void tracing_map_destroy(struct tracing_map *map) +{ + if (!map) + return; + + tracing_map_free_elts(map); + + tracing_map_array_free(map->map); + kfree(map); +} + +/** + * tracing_map_clear - Clear a tracing_map + * @map: The tracing_map to clear + * + * Resets the tracing map to a cleared or initial state. The + * tracing_map_elts are all cleared, and the array of struct + * tracing_map_entry is reset to an initialized state. + * + * Callers should make sure there are no writers actively inserting + * into the map before calling this. + */ +void tracing_map_clear(struct tracing_map *map) +{ + unsigned int i; + + atomic_set(&map->next_elt, -1); + atomic64_set(&map->hits, 0); + atomic64_set(&map->drops, 0); + + tracing_map_array_clear(map->map); + + for (i = 0; i < map->max_elts; i++) + tracing_map_elt_clear(*(TRACING_MAP_ELT(map->elts, i))); +} + +static void set_sort_key(struct tracing_map *map, + struct tracing_map_sort_key *sort_key) +{ + map->sort_key = *sort_key; +} + +/** + * tracing_map_create - Create a lock-free map and element pool + * @map_bits: The size of the map (2 ** map_bits) + * @key_size: The size of the key for the map in bytes + * @ops: Optional client-defined tracing_map_ops instance + * @private_data: Client data associated with the map + * + * Creates and sets up a map to contain 2 ** map_bits number of + * elements (internally maintained as 'max_elts' in struct + * tracing_map). Before using, map fields should be added to the map + * with tracing_map_add_sum_field() and tracing_map_add_key_field(). + * tracing_map_init() should then be called to allocate the array of + * tracing_map_elts, in order to avoid allocating anything in the map + * insertion path. The user-specified map size reflects the maximum + * number of elements that can be contained in the table requested by + * the user - internally we double that in order to keep the table + * sparse and keep collisions manageable. + * + * A tracing_map is a special-purpose map designed to aggregate or + * 'sum' one or more values associated with a specific object of type + * tracing_map_elt, which is attached by the map to a given key. + * + * tracing_map_create() sets up the map itself, and provides + * operations for inserting tracing_map_elts, but doesn't allocate the + * tracing_map_elts themselves, or provide a means for describing the + * keys or sums associated with the tracing_map_elts. All + * tracing_map_elts for a given map have the same set of sums and + * keys, which are defined by the client using the functions + * tracing_map_add_key_field() and tracing_map_add_sum_field(). Once + * the fields are defined, the pool of elements allocated for the map + * can be created, which occurs when the client code calls + * tracing_map_init(). + * + * When tracing_map_init() returns, tracing_map_elt elements can be + * inserted into the map using tracing_map_insert(). When called, + * tracing_map_insert() grabs a free tracing_map_elt from the pool, or + * finds an existing match in the map and in either case returns it. + * The client can then use tracing_map_update_sum() and + * tracing_map_read_sum() to update or read a given sum field for the + * tracing_map_elt. + * + * The client can at any point retrieve and traverse the current set + * of inserted tracing_map_elts in a tracing_map, via + * tracing_map_sort_entries(). Sorting can be done on any field, + * including keys. + * + * See tracing_map.h for a description of tracing_map_ops. + * + * Return: the tracing_map pointer if successful, ERR_PTR if not. + */ +struct tracing_map *tracing_map_create(unsigned int map_bits, + unsigned int key_size, + const struct tracing_map_ops *ops, + void *private_data) +{ + struct tracing_map *map; + unsigned int i; + + if (map_bits < TRACING_MAP_BITS_MIN || + map_bits > TRACING_MAP_BITS_MAX) + return ERR_PTR(-EINVAL); + + map = kzalloc(sizeof(*map), GFP_KERNEL); + if (!map) + return ERR_PTR(-ENOMEM); + + map->map_bits = map_bits; + map->max_elts = (1 << map_bits); + atomic_set(&map->next_elt, -1); + + map->map_size = (1 << (map_bits + 1)); + map->ops = ops; + + map->private_data = private_data; + + map->map = tracing_map_array_alloc(map->map_size, + sizeof(struct tracing_map_entry)); + if (!map->map) + goto free; + + map->key_size = key_size; + for (i = 0; i < TRACING_MAP_KEYS_MAX; i++) + map->key_idx[i] = -1; + out: + return map; + free: + tracing_map_destroy(map); + map = ERR_PTR(-ENOMEM); + + goto out; +} + +/** + * tracing_map_init - Allocate and clear a map's tracing_map_elts + * @map: The tracing_map to initialize + * + * Allocates a clears a pool of tracing_map_elts equal to the + * user-specified size of 2 ** map_bits (internally maintained as + * 'max_elts' in struct tracing_map). Before using, the map fields + * should be added to the map with tracing_map_add_sum_field() and + * tracing_map_add_key_field(). tracing_map_init() should then be + * called to allocate the array of tracing_map_elts, in order to avoid + * allocating anything in the map insertion path. The user-specified + * map size reflects the max number of elements requested by the user + * - internally we double that in order to keep the table sparse and + * keep collisions manageable. + * + * See tracing_map.h for a description of tracing_map_ops. + * + * Return: the tracing_map pointer if successful, ERR_PTR if not. + */ +int tracing_map_init(struct tracing_map *map) +{ + int err; + + if (map->n_fields < 2) + return -EINVAL; /* need at least 1 key and 1 val */ + + err = tracing_map_alloc_elts(map); + if (err) + return err; + + tracing_map_clear(map); + + return err; +} + +static int cmp_entries_dup(const struct tracing_map_sort_entry **a, + const struct tracing_map_sort_entry **b) +{ + int ret = 0; + + if (memcmp((*a)->key, (*b)->key, (*a)->elt->map->key_size)) + ret = 1; + + return ret; +} + +static int cmp_entries_sum(const struct tracing_map_sort_entry **a, + const struct tracing_map_sort_entry **b) +{ + const struct tracing_map_elt *elt_a, *elt_b; + struct tracing_map_sort_key *sort_key; + struct tracing_map_field *field; + tracing_map_cmp_fn_t cmp_fn; + void *val_a, *val_b; + int ret = 0; + + elt_a = (*a)->elt; + elt_b = (*b)->elt; + + sort_key = &elt_a->map->sort_key; + + field = &elt_a->fields[sort_key->field_idx]; + cmp_fn = field->cmp_fn; + + val_a = &elt_a->fields[sort_key->field_idx].sum; + val_b = &elt_b->fields[sort_key->field_idx].sum; + + ret = cmp_fn(val_a, val_b); + if (sort_key->descending) + ret = -ret; + + return ret; +} + +static int cmp_entries_key(const struct tracing_map_sort_entry **a, + const struct tracing_map_sort_entry **b) +{ + const struct tracing_map_elt *elt_a, *elt_b; + struct tracing_map_sort_key *sort_key; + struct tracing_map_field *field; + tracing_map_cmp_fn_t cmp_fn; + void *val_a, *val_b; + int ret = 0; + + elt_a = (*a)->elt; + elt_b = (*b)->elt; + + sort_key = &elt_a->map->sort_key; + + field = &elt_a->fields[sort_key->field_idx]; + + cmp_fn = field->cmp_fn; + + val_a = elt_a->key + field->offset; + val_b = elt_b->key + field->offset; + + ret = cmp_fn(val_a, val_b); + if (sort_key->descending) + ret = -ret; + + return ret; +} + +static void destroy_sort_entry(struct tracing_map_sort_entry *entry) +{ + if (!entry) + return; + + if (entry->elt_copied) + tracing_map_elt_free(entry->elt); + + kfree(entry); +} + +/** + * tracing_map_destroy_sort_entries - Destroy an array of sort entries + * @entries: The entries to destroy + * @n_entries: The number of entries in the array + * + * Destroy the elements returned by a tracing_map_sort_entries() call. + */ +void tracing_map_destroy_sort_entries(struct tracing_map_sort_entry **entries, + unsigned int n_entries) +{ + unsigned int i; + + for (i = 0; i < n_entries; i++) + destroy_sort_entry(entries[i]); + + vfree(entries); +} + +static struct tracing_map_sort_entry * +create_sort_entry(void *key, struct tracing_map_elt *elt) +{ + struct tracing_map_sort_entry *sort_entry; + + sort_entry = kzalloc(sizeof(*sort_entry), GFP_KERNEL); + if (!sort_entry) + return NULL; + + sort_entry->key = key; + sort_entry->elt = elt; + + return sort_entry; +} + +static struct tracing_map_elt *copy_elt(struct tracing_map_elt *elt) +{ + struct tracing_map_elt *dup_elt; + unsigned int i; + + dup_elt = tracing_map_elt_alloc(elt->map); + if (IS_ERR(dup_elt)) + return NULL; + + if (elt->map->ops && elt->map->ops->elt_copy) + elt->map->ops->elt_copy(dup_elt, elt); + + dup_elt->private_data = elt->private_data; + memcpy(dup_elt->key, elt->key, elt->map->key_size); + + for (i = 0; i < elt->map->n_fields; i++) { + atomic64_set(&dup_elt->fields[i].sum, + atomic64_read(&elt->fields[i].sum)); + dup_elt->fields[i].cmp_fn = elt->fields[i].cmp_fn; + } + + return dup_elt; +} + +static int merge_dup(struct tracing_map_sort_entry **sort_entries, + unsigned int target, unsigned int dup) +{ + struct tracing_map_elt *target_elt, *elt; + bool first_dup = (target - dup) == 1; + int i; + + if (first_dup) { + elt = sort_entries[target]->elt; + target_elt = copy_elt(elt); + if (!target_elt) + return -ENOMEM; + sort_entries[target]->elt = target_elt; + sort_entries[target]->elt_copied = true; + } else + target_elt = sort_entries[target]->elt; + + elt = sort_entries[dup]->elt; + + for (i = 0; i < elt->map->n_fields; i++) + atomic64_add(atomic64_read(&elt->fields[i].sum), + &target_elt->fields[i].sum); + + sort_entries[dup]->dup = true; + + return 0; +} + +static int merge_dups(struct tracing_map_sort_entry **sort_entries, + int n_entries, unsigned int key_size) +{ + unsigned int dups = 0, total_dups = 0; + int err, i, j; + void *key; + + if (n_entries < 2) + return total_dups; + + sort(sort_entries, n_entries, sizeof(struct tracing_map_sort_entry *), + (int (*)(const void *, const void *))cmp_entries_dup, NULL); + + key = sort_entries[0]->key; + for (i = 1; i < n_entries; i++) { + if (!memcmp(sort_entries[i]->key, key, key_size)) { + dups++; total_dups++; + err = merge_dup(sort_entries, i - dups, i); + if (err) + return err; + continue; + } + key = sort_entries[i]->key; + dups = 0; + } + + if (!total_dups) + return total_dups; + + for (i = 0, j = 0; i < n_entries; i++) { + if (!sort_entries[i]->dup) { + sort_entries[j] = sort_entries[i]; + if (j++ != i) + sort_entries[i] = NULL; + } else { + destroy_sort_entry(sort_entries[i]); + sort_entries[i] = NULL; + } + } + + return total_dups; +} + +static bool is_key(struct tracing_map *map, unsigned int field_idx) +{ + unsigned int i; + + for (i = 0; i < map->n_keys; i++) + if (map->key_idx[i] == field_idx) + return true; + return false; +} + +static void sort_secondary(struct tracing_map *map, + const struct tracing_map_sort_entry **entries, + unsigned int n_entries, + struct tracing_map_sort_key *primary_key, + struct tracing_map_sort_key *secondary_key) +{ + int (*primary_fn)(const struct tracing_map_sort_entry **, + const struct tracing_map_sort_entry **); + int (*secondary_fn)(const struct tracing_map_sort_entry **, + const struct tracing_map_sort_entry **); + unsigned i, start = 0, n_sub = 1; + + if (is_key(map, primary_key->field_idx)) + primary_fn = cmp_entries_key; + else + primary_fn = cmp_entries_sum; + + if (is_key(map, secondary_key->field_idx)) + secondary_fn = cmp_entries_key; + else + secondary_fn = cmp_entries_sum; + + for (i = 0; i < n_entries - 1; i++) { + const struct tracing_map_sort_entry **a = &entries[i]; + const struct tracing_map_sort_entry **b = &entries[i + 1]; + + if (primary_fn(a, b) == 0) { + n_sub++; + if (i < n_entries - 2) + continue; + } + + if (n_sub < 2) { + start = i + 1; + n_sub = 1; + continue; + } + + set_sort_key(map, secondary_key); + sort(&entries[start], n_sub, + sizeof(struct tracing_map_sort_entry *), + (int (*)(const void *, const void *))secondary_fn, NULL); + set_sort_key(map, primary_key); + + start = i + 1; + n_sub = 1; + } +} + +/** + * tracing_map_sort_entries - Sort the current set of tracing_map_elts in a map + * @map: The tracing_map + * @sort_key: The sort key to use for sorting + * @sort_entries: outval: pointer to allocated and sorted array of entries + * + * tracing_map_sort_entries() sorts the current set of entries in the + * map and returns the list of tracing_map_sort_entries containing + * them to the client in the sort_entries param. The client can + * access the struct tracing_map_elt element of interest directly as + * the 'elt' field of a returned struct tracing_map_sort_entry object. + * + * The sort_key has only two fields: idx and descending. 'idx' refers + * to the index of the field added via tracing_map_add_sum_field() or + * tracing_map_add_key_field() when the tracing_map was initialized. + * 'descending' is a flag that if set reverses the sort order, which + * by default is ascending. + * + * The client should not hold on to the returned array but should use + * it and call tracing_map_destroy_sort_entries() when done. + * + * Return: the number of sort_entries in the struct tracing_map_sort_entry + * array, negative on error + */ +int tracing_map_sort_entries(struct tracing_map *map, + struct tracing_map_sort_key *sort_keys, + unsigned int n_sort_keys, + struct tracing_map_sort_entry ***sort_entries) +{ + int (*cmp_entries_fn)(const struct tracing_map_sort_entry **, + const struct tracing_map_sort_entry **); + struct tracing_map_sort_entry *sort_entry, **entries; + int i, n_entries, ret; + + entries = vmalloc(map->max_elts * sizeof(sort_entry)); + if (!entries) + return -ENOMEM; + + for (i = 0, n_entries = 0; i < map->map_size; i++) { + struct tracing_map_entry *entry; + + entry = TRACING_MAP_ENTRY(map->map, i); + + if (!entry->key || !entry->val) + continue; + + entries[n_entries] = create_sort_entry(entry->val->key, + entry->val); + if (!entries[n_entries++]) { + ret = -ENOMEM; + goto free; + } + } + + if (n_entries == 0) { + ret = 0; + goto free; + } + + if (n_entries == 1) { + *sort_entries = entries; + return 1; + } + + ret = merge_dups(entries, n_entries, map->key_size); + if (ret < 0) + goto free; + n_entries -= ret; + + if (is_key(map, sort_keys[0].field_idx)) + cmp_entries_fn = cmp_entries_key; + else + cmp_entries_fn = cmp_entries_sum; + + set_sort_key(map, &sort_keys[0]); + + sort(entries, n_entries, sizeof(struct tracing_map_sort_entry *), + (int (*)(const void *, const void *))cmp_entries_fn, NULL); + + if (n_sort_keys > 1) + sort_secondary(map, + (const struct tracing_map_sort_entry **)entries, + n_entries, + &sort_keys[0], + &sort_keys[1]); + + *sort_entries = entries; + + return n_entries; + free: + tracing_map_destroy_sort_entries(entries, n_entries); + + return ret; +} diff --git a/kernel/trace/tracing_map.h b/kernel/trace/tracing_map.h new file mode 100644 index 000000000000..618838f5f30a --- /dev/null +++ b/kernel/trace/tracing_map.h @@ -0,0 +1,283 @@ +#ifndef __TRACING_MAP_H +#define __TRACING_MAP_H + +#define TRACING_MAP_BITS_DEFAULT 11 +#define TRACING_MAP_BITS_MAX 17 +#define TRACING_MAP_BITS_MIN 7 + +#define TRACING_MAP_KEYS_MAX 2 +#define TRACING_MAP_VALS_MAX 3 +#define TRACING_MAP_FIELDS_MAX (TRACING_MAP_KEYS_MAX + \ + TRACING_MAP_VALS_MAX) +#define TRACING_MAP_SORT_KEYS_MAX 2 + +typedef int (*tracing_map_cmp_fn_t) (void *val_a, void *val_b); + +/* + * This is an overview of the tracing_map data structures and how they + * relate to the tracing_map API. The details of the algorithms + * aren't discussed here - this is just a general overview of the data + * structures and how they interact with the API. + * + * The central data structure of the tracing_map is an initially + * zeroed array of struct tracing_map_entry (stored in the map field + * of struct tracing_map). tracing_map_entry is a very simple data + * structure containing only two fields: a 32-bit unsigned 'key' + * variable and a pointer named 'val'. This array of struct + * tracing_map_entry is essentially a hash table which will be + * modified by a single function, tracing_map_insert(), but which can + * be traversed and read by a user at any time (though the user does + * this indirectly via an array of tracing_map_sort_entry - see the + * explanation of that data structure in the discussion of the + * sorting-related data structures below). + * + * The central function of the tracing_map API is + * tracing_map_insert(). tracing_map_insert() hashes the + * arbitrarily-sized key passed into it into a 32-bit unsigned key. + * It then uses this key, truncated to the array size, as an index + * into the array of tracing_map_entries. If the value of the 'key' + * field of the tracing_map_entry found at that location is 0, then + * that entry is considered to be free and can be claimed, by + * replacing the 0 in the 'key' field of the tracing_map_entry with + * the new 32-bit hashed key. Once claimed, that tracing_map_entry's + * 'val' field is then used to store a unique element which will be + * forever associated with that 32-bit hashed key in the + * tracing_map_entry. + * + * That unique element now in the tracing_map_entry's 'val' field is + * an instance of tracing_map_elt, where 'elt' in the latter part of + * that variable name is short for 'element'. The purpose of a + * tracing_map_elt is to hold values specific to the particular + * 32-bit hashed key it's assocated with. Things such as the unique + * set of aggregated sums associated with the 32-bit hashed key, along + * with a copy of the full key associated with the entry, and which + * was used to produce the 32-bit hashed key. + * + * When tracing_map_create() is called to create the tracing map, the + * user specifies (indirectly via the map_bits param, the details are + * unimportant for this discussion) the maximum number of elements + * that the map can hold (stored in the max_elts field of struct + * tracing_map). This is the maximum possible number of + * tracing_map_entries in the tracing_map_entry array which can be + * 'claimed' as described in the above discussion, and therefore is + * also the maximum number of tracing_map_elts that can be associated + * with the tracing_map_entry array in the tracing_map. Because of + * the way the insertion algorithm works, the size of the allocated + * tracing_map_entry array is always twice the maximum number of + * elements (2 * max_elts). This value is stored in the map_size + * field of struct tracing_map. + * + * Because tracing_map_insert() needs to work from any context, + * including from within the memory allocation functions themselves, + * both the tracing_map_entry array and a pool of max_elts + * tracing_map_elts are pre-allocated before any call is made to + * tracing_map_insert(). + * + * The tracing_map_entry array is allocated as a single block by + * tracing_map_create(). + * + * Because the tracing_map_elts are much larger objects and can't + * generally be allocated together as a single large array without + * failure, they're allocated individually, by tracing_map_init(). + * + * The pool of tracing_map_elts are allocated by tracing_map_init() + * rather than by tracing_map_create() because at the time + * tracing_map_create() is called, there isn't enough information to + * create the tracing_map_elts. Specifically,the user first needs to + * tell the tracing_map implementation how many fields the + * tracing_map_elts contain, and which types of fields they are (key + * or sum). The user does this via the tracing_map_add_sum_field() + * and tracing_map_add_key_field() functions, following which the user + * calls tracing_map_init() to finish up the tracing map setup. The + * array holding the pointers which make up the pre-allocated pool of + * tracing_map_elts is allocated as a single block and is stored in + * the elts field of struct tracing_map. + * + * There is also a set of structures used for sorting that might + * benefit from some minimal explanation. + * + * struct tracing_map_sort_key is used to drive the sort at any given + * time. By 'any given time' we mean that a different + * tracing_map_sort_key will be used at different times depending on + * whether the sort currently being performed is a primary or a + * secondary sort. + * + * The sort key is very simple, consisting of the field index of the + * tracing_map_elt field to sort on (which the user saved when adding + * the field), and whether the sort should be done in an ascending or + * descending order. + * + * For the convenience of the sorting code, a tracing_map_sort_entry + * is created for each tracing_map_elt, again individually allocated + * to avoid failures that might be expected if allocated as a single + * large array of struct tracing_map_sort_entry. + * tracing_map_sort_entry instances are the objects expected by the + * various internal sorting functions, and are also what the user + * ultimately receives after calling tracing_map_sort_entries(). + * Because it doesn't make sense for users to access an unordered and + * sparsely populated tracing_map directly, the + * tracing_map_sort_entries() function is provided so that users can + * retrieve a sorted list of all existing elements. In addition to + * the associated tracing_map_elt 'elt' field contained within the + * tracing_map_sort_entry, which is the object of interest to the + * user, tracing_map_sort_entry objects contain a number of additional + * fields which are used for caching and internal purposes and can + * safely be ignored. +*/ + +struct tracing_map_field { + tracing_map_cmp_fn_t cmp_fn; + union { + atomic64_t sum; + unsigned int offset; + }; +}; + +struct tracing_map_elt { + struct tracing_map *map; + struct tracing_map_field *fields; + void *key; + void *private_data; +}; + +struct tracing_map_entry { + u32 key; + struct tracing_map_elt *val; +}; + +struct tracing_map_sort_key { + unsigned int field_idx; + bool descending; +}; + +struct tracing_map_sort_entry { + void *key; + struct tracing_map_elt *elt; + bool elt_copied; + bool dup; +}; + +struct tracing_map_array { + unsigned int entries_per_page; + unsigned int entry_size_shift; + unsigned int entry_shift; + unsigned int entry_mask; + unsigned int n_pages; + void **pages; +}; + +#define TRACING_MAP_ARRAY_ELT(array, idx) \ + (array->pages[idx >> array->entry_shift] + \ + ((idx & array->entry_mask) << array->entry_size_shift)) + +#define TRACING_MAP_ENTRY(array, idx) \ + ((struct tracing_map_entry *)TRACING_MAP_ARRAY_ELT(array, idx)) + +#define TRACING_MAP_ELT(array, idx) \ + ((struct tracing_map_elt **)TRACING_MAP_ARRAY_ELT(array, idx)) + +struct tracing_map { + unsigned int key_size; + unsigned int map_bits; + unsigned int map_size; + unsigned int max_elts; + atomic_t next_elt; + struct tracing_map_array *elts; + struct tracing_map_array *map; + const struct tracing_map_ops *ops; + void *private_data; + struct tracing_map_field fields[TRACING_MAP_FIELDS_MAX]; + unsigned int n_fields; + int key_idx[TRACING_MAP_KEYS_MAX]; + unsigned int n_keys; + struct tracing_map_sort_key sort_key; + atomic64_t hits; + atomic64_t drops; +}; + +/** + * struct tracing_map_ops - callbacks for tracing_map + * + * The methods in this structure define callback functions for various + * operations on a tracing_map or objects related to a tracing_map. + * + * For a detailed description of tracing_map_elt objects please see + * the overview of tracing_map data structures at the beginning of + * this file. + * + * All the methods below are optional. + * + * @elt_alloc: When a tracing_map_elt is allocated, this function, if + * defined, will be called and gives clients the opportunity to + * allocate additional data and attach it to the element + * (tracing_map_elt->private_data is meant for that purpose). + * Element allocation occurs before tracing begins, when the + * tracing_map_init() call is made by client code. + * + * @elt_copy: At certain points in the lifetime of an element, it may + * need to be copied. The copy should include a copy of the + * client-allocated data, which can be copied into the 'to' + * element from the 'from' element. + * + * @elt_free: When a tracing_map_elt is freed, this function is called + * and allows client-allocated per-element data to be freed. + * + * @elt_clear: This callback allows per-element client-defined data to + * be cleared, if applicable. + * + * @elt_init: This callback allows per-element client-defined data to + * be initialized when used i.e. when the element is actually + * claimed by tracing_map_insert() in the context of the map + * insertion. + */ +struct tracing_map_ops { + int (*elt_alloc)(struct tracing_map_elt *elt); + void (*elt_copy)(struct tracing_map_elt *to, + struct tracing_map_elt *from); + void (*elt_free)(struct tracing_map_elt *elt); + void (*elt_clear)(struct tracing_map_elt *elt); + void (*elt_init)(struct tracing_map_elt *elt); +}; + +extern struct tracing_map * +tracing_map_create(unsigned int map_bits, + unsigned int key_size, + const struct tracing_map_ops *ops, + void *private_data); +extern int tracing_map_init(struct tracing_map *map); + +extern int tracing_map_add_sum_field(struct tracing_map *map); +extern int tracing_map_add_key_field(struct tracing_map *map, + unsigned int offset, + tracing_map_cmp_fn_t cmp_fn); + +extern void tracing_map_destroy(struct tracing_map *map); +extern void tracing_map_clear(struct tracing_map *map); + +extern struct tracing_map_elt * +tracing_map_insert(struct tracing_map *map, void *key); +extern struct tracing_map_elt * +tracing_map_lookup(struct tracing_map *map, void *key); + +extern tracing_map_cmp_fn_t tracing_map_cmp_num(int field_size, + int field_is_signed); +extern int tracing_map_cmp_string(void *val_a, void *val_b); +extern int tracing_map_cmp_none(void *val_a, void *val_b); + +extern void tracing_map_update_sum(struct tracing_map_elt *elt, + unsigned int i, u64 n); +extern u64 tracing_map_read_sum(struct tracing_map_elt *elt, unsigned int i); +extern void tracing_map_set_field_descr(struct tracing_map *map, + unsigned int i, + unsigned int key_offset, + tracing_map_cmp_fn_t cmp_fn); +extern int +tracing_map_sort_entries(struct tracing_map *map, + struct tracing_map_sort_key *sort_keys, + unsigned int n_sort_keys, + struct tracing_map_sort_entry ***sort_entries); + +extern void +tracing_map_destroy_sort_entries(struct tracing_map_sort_entry **entries, + unsigned int n_entries); +#endif /* __TRACING_MAP_H */ diff --git a/kernel/workqueue.c b/kernel/workqueue.c index 2232ae3e3ad6..5f5068e94003 100644 --- a/kernel/workqueue.c +++ b/kernel/workqueue.c @@ -666,6 +666,35 @@ static void set_work_pool_and_clear_pending(struct work_struct *work, */ smp_wmb(); set_work_data(work, (unsigned long)pool_id << WORK_OFFQ_POOL_SHIFT, 0); + /* + * The following mb guarantees that previous clear of a PENDING bit + * will not be reordered with any speculative LOADS or STORES from + * work->current_func, which is executed afterwards. This possible + * reordering can lead to a missed execution on attempt to qeueue + * the same @work. E.g. consider this case: + * + * CPU#0 CPU#1 + * ---------------------------- -------------------------------- + * + * 1 STORE event_indicated + * 2 queue_work_on() { + * 3 test_and_set_bit(PENDING) + * 4 } set_..._and_clear_pending() { + * 5 set_work_data() # clear bit + * 6 smp_mb() + * 7 work->current_func() { + * 8 LOAD event_indicated + * } + * + * Without an explicit full barrier speculative LOAD on line 8 can + * be executed before CPU#0 does STORE on line 1. If that happens, + * CPU#0 observes the PENDING bit is still set and new execution of + * a @work is not queued in a hope, that CPU#1 will eventually + * finish the queued @work. Meanwhile CPU#1 does not see + * event_indicated is set, because speculative LOAD was executed + * before actual STORE. + */ + smp_mb(); } static void clear_work_data(struct work_struct *work) @@ -4525,6 +4554,17 @@ static void rebind_workers(struct worker_pool *pool) pool->attrs->cpumask) < 0); spin_lock_irq(&pool->lock); + + /* + * XXX: CPU hotplug notifiers are weird and can call DOWN_FAILED + * w/o preceding DOWN_PREPARE. Work around it. CPU hotplug is + * being reworked and this can go away in time. + */ + if (!(pool->flags & POOL_DISASSOCIATED)) { + spin_unlock_irq(&pool->lock); + return; + } + pool->flags &= ~POOL_DISASSOCIATED; for_each_pool_worker(worker, pool) { |