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-rw-r--r--kernel/acct.c14
-rw-r--r--kernel/async.c8
-rw-r--r--kernel/auditsc.c2
-rw-r--r--kernel/bpf/Makefile6
-rw-r--r--kernel/bpf/core.c127
-rw-r--r--kernel/bpf/syscall.c606
-rw-r--r--kernel/bpf/test_stub.c116
-rw-r--r--kernel/bpf/verifier.c1923
-rw-r--r--kernel/cgroup.c239
-rw-r--r--kernel/compat.c24
-rw-r--r--kernel/configs/tiny.config4
-rw-r--r--kernel/cpu.c16
-rw-r--r--kernel/cpuset.c24
-rw-r--r--kernel/crash_dump.c1
-rw-r--r--kernel/debug/kdb/kdb_bp.c6
-rw-r--r--kernel/events/callchain.c2
-rw-r--r--kernel/events/core.c256
-rw-r--r--kernel/exit.c50
-rw-r--r--kernel/fork.c21
-rw-r--r--kernel/futex.c1
-rw-r--r--kernel/gcov/Kconfig2
-rw-r--r--kernel/irq/Kconfig3
-rw-r--r--kernel/irq/chip.c86
-rw-r--r--kernel/irq/devres.c2
-rw-r--r--kernel/irq/internals.h16
-rw-r--r--kernel/irq/irqdesc.c42
-rw-r--r--kernel/irq/manage.c32
-rw-r--r--kernel/irq/pm.c159
-rw-r--r--kernel/irq_work.c15
-rw-r--r--kernel/kallsyms.c11
-rw-r--r--kernel/kcmp.c7
-rw-r--r--kernel/kexec.c43
-rw-r--r--kernel/kprobes.c13
-rw-r--r--kernel/kthread.c2
-rw-r--r--kernel/locking/locktorture.c529
-rw-r--r--kernel/locking/mcs_spinlock.h3
-rw-r--r--kernel/locking/mutex.c416
-rw-r--r--kernel/locking/mutex.h2
-rw-r--r--kernel/locking/rtmutex.c2
-rw-r--r--kernel/locking/rwsem-xadd.c27
-rw-r--r--kernel/locking/semaphore.c12
-rw-r--r--kernel/module.c4
-rw-r--r--kernel/params.c24
-rw-r--r--kernel/power/Kconfig4
-rw-r--r--kernel/power/power.h1
-rw-r--r--kernel/power/process.c1
-rw-r--r--kernel/power/snapshot.c4
-rw-r--r--kernel/power/suspend.c53
-rw-r--r--kernel/power/suspend_test.c61
-rw-r--r--kernel/printk/printk.c40
-rw-r--r--kernel/rcu/rcutorture.c278
-rw-r--r--kernel/rcu/tiny.c20
-rw-r--r--kernel/rcu/tree.c115
-rw-r--r--kernel/rcu/tree.h20
-rw-r--r--kernel/rcu/tree_plugin.h426
-rw-r--r--kernel/rcu/update.c345
-rw-r--r--kernel/reboot.c81
-rw-r--r--kernel/resource.c117
-rw-r--r--kernel/sched/auto_group.c5
-rw-r--r--kernel/sched/core.c323
-rw-r--r--kernel/sched/cpudeadline.c4
-rw-r--r--kernel/sched/cputime.c64
-rw-r--r--kernel/sched/deadline.c33
-rw-r--r--kernel/sched/debug.c13
-rw-r--r--kernel/sched/fair.c481
-rw-r--r--kernel/sched/idle.c6
-rw-r--r--kernel/sched/rt.c21
-rw-r--r--kernel/sched/sched.h80
-rw-r--r--kernel/sched/stop_task.c2
-rw-r--r--kernel/sched/wait.c36
-rw-r--r--kernel/seccomp.c259
-rw-r--r--kernel/smp.c22
-rw-r--r--kernel/softirq.c2
-rw-r--r--kernel/sys.c491
-rw-r--r--kernel/sys_ni.c6
-rw-r--r--kernel/sysctl.c16
-rw-r--r--kernel/sysctl_binary.c1
-rw-r--r--kernel/time/alarmtimer.c34
-rw-r--r--kernel/time/hrtimer.c1
-rw-r--r--kernel/time/posix-cpu-timers.c14
-rw-r--r--kernel/time/tick-common.c1
-rw-r--r--kernel/time/tick-internal.h7
-rw-r--r--kernel/time/tick-sched.c76
-rw-r--r--kernel/time/time.c56
-rw-r--r--kernel/time/timekeeping.c5
-rw-r--r--kernel/time/timer.c2
-rw-r--r--kernel/torture.c32
-rw-r--r--kernel/trace/ftrace.c608
-rw-r--r--kernel/trace/ring_buffer.c18
-rw-r--r--kernel/trace/ring_buffer_benchmark.c3
-rw-r--r--kernel/trace/trace_events.c5
-rw-r--r--kernel/trace/trace_selftest.c51
-rw-r--r--kernel/trace/trace_stack.c4
-rw-r--r--kernel/trace/trace_syscalls.c4
-rw-r--r--kernel/watchdog.c78
-rw-r--r--kernel/workqueue.c5
96 files changed, 7268 insertions, 2065 deletions
diff --git a/kernel/acct.c b/kernel/acct.c
index b4c667d22e79..33738ef972f3 100644
--- a/kernel/acct.c
+++ b/kernel/acct.c
@@ -472,7 +472,6 @@ static void do_acct_process(struct bsd_acct_struct *acct)
acct_t ac;
unsigned long flim;
const struct cred *orig_cred;
- struct pid_namespace *ns = acct->ns;
struct file *file = acct->file;
/*
@@ -500,10 +499,15 @@ static void do_acct_process(struct bsd_acct_struct *acct)
ac.ac_gid16 = ac.ac_gid;
#endif
#if ACCT_VERSION == 3
- ac.ac_pid = task_tgid_nr_ns(current, ns);
- rcu_read_lock();
- ac.ac_ppid = task_tgid_nr_ns(rcu_dereference(current->real_parent), ns);
- rcu_read_unlock();
+ {
+ struct pid_namespace *ns = acct->ns;
+
+ ac.ac_pid = task_tgid_nr_ns(current, ns);
+ rcu_read_lock();
+ ac.ac_ppid = task_tgid_nr_ns(rcu_dereference(current->real_parent),
+ ns);
+ rcu_read_unlock();
+ }
#endif
/*
* Get freeze protection. If the fs is frozen, just skip the write
diff --git a/kernel/async.c b/kernel/async.c
index 61f023ce0228..4c3773c0bf63 100644
--- a/kernel/async.c
+++ b/kernel/async.c
@@ -115,7 +115,7 @@ static void async_run_entry_fn(struct work_struct *work)
/* 1) run (and print duration) */
if (initcall_debug && system_state == SYSTEM_BOOTING) {
- printk(KERN_DEBUG "calling %lli_%pF @ %i\n",
+ pr_debug("calling %lli_%pF @ %i\n",
(long long)entry->cookie,
entry->func, task_pid_nr(current));
calltime = ktime_get();
@@ -124,7 +124,7 @@ static void async_run_entry_fn(struct work_struct *work)
if (initcall_debug && system_state == SYSTEM_BOOTING) {
rettime = ktime_get();
delta = ktime_sub(rettime, calltime);
- printk(KERN_DEBUG "initcall %lli_%pF returned 0 after %lld usecs\n",
+ pr_debug("initcall %lli_%pF returned 0 after %lld usecs\n",
(long long)entry->cookie,
entry->func,
(long long)ktime_to_ns(delta) >> 10);
@@ -285,7 +285,7 @@ void async_synchronize_cookie_domain(async_cookie_t cookie, struct async_domain
ktime_t uninitialized_var(starttime), delta, endtime;
if (initcall_debug && system_state == SYSTEM_BOOTING) {
- printk(KERN_DEBUG "async_waiting @ %i\n", task_pid_nr(current));
+ pr_debug("async_waiting @ %i\n", task_pid_nr(current));
starttime = ktime_get();
}
@@ -295,7 +295,7 @@ void async_synchronize_cookie_domain(async_cookie_t cookie, struct async_domain
endtime = ktime_get();
delta = ktime_sub(endtime, starttime);
- printk(KERN_DEBUG "async_continuing @ %i after %lli usec\n",
+ pr_debug("async_continuing @ %i after %lli usec\n",
task_pid_nr(current),
(long long)ktime_to_ns(delta) >> 10);
}
diff --git a/kernel/auditsc.c b/kernel/auditsc.c
index 21eae3c05ec0..7208c1df248d 100644
--- a/kernel/auditsc.c
+++ b/kernel/auditsc.c
@@ -2406,7 +2406,7 @@ int __audit_log_bprm_fcaps(struct linux_binprm *bprm,
* @new: the new credentials
* @old: the old (current) credentials
*
- * Record the aguments userspace sent to sys_capset for later printing by the
+ * Record the arguments userspace sent to sys_capset for later printing by the
* audit system if applicable
*/
void __audit_log_capset(const struct cred *new, const struct cred *old)
diff --git a/kernel/bpf/Makefile b/kernel/bpf/Makefile
index 6a71145e2769..45427239f375 100644
--- a/kernel/bpf/Makefile
+++ b/kernel/bpf/Makefile
@@ -1 +1,5 @@
-obj-y := core.o
+obj-y := core.o syscall.o verifier.o
+
+ifdef CONFIG_TEST_BPF
+obj-y += test_stub.o
+endif
diff --git a/kernel/bpf/core.c b/kernel/bpf/core.c
index 7f0dbcbb34af..f0c30c59b317 100644
--- a/kernel/bpf/core.c
+++ b/kernel/bpf/core.c
@@ -20,9 +20,14 @@
* Andi Kleen - Fix a few bad bugs and races.
* Kris Katterjohn - Added many additional checks in bpf_check_classic()
*/
+
#include <linux/filter.h>
#include <linux/skbuff.h>
+#include <linux/vmalloc.h>
+#include <linux/random.h>
+#include <linux/moduleloader.h>
#include <asm/unaligned.h>
+#include <linux/bpf.h>
/* Registers */
#define BPF_R0 regs[BPF_REG_0]
@@ -63,6 +68,105 @@ void *bpf_internal_load_pointer_neg_helper(const struct sk_buff *skb, int k, uns
return NULL;
}
+struct bpf_prog *bpf_prog_alloc(unsigned int size, gfp_t gfp_extra_flags)
+{
+ gfp_t gfp_flags = GFP_KERNEL | __GFP_HIGHMEM | __GFP_ZERO |
+ gfp_extra_flags;
+ struct bpf_prog_aux *aux;
+ struct bpf_prog *fp;
+
+ size = round_up(size, PAGE_SIZE);
+ fp = __vmalloc(size, gfp_flags, PAGE_KERNEL);
+ if (fp == NULL)
+ return NULL;
+
+ aux = kzalloc(sizeof(*aux), GFP_KERNEL | gfp_extra_flags);
+ if (aux == NULL) {
+ vfree(fp);
+ return NULL;
+ }
+
+ fp->pages = size / PAGE_SIZE;
+ fp->aux = aux;
+
+ return fp;
+}
+EXPORT_SYMBOL_GPL(bpf_prog_alloc);
+
+struct bpf_prog *bpf_prog_realloc(struct bpf_prog *fp_old, unsigned int size,
+ gfp_t gfp_extra_flags)
+{
+ gfp_t gfp_flags = GFP_KERNEL | __GFP_HIGHMEM | __GFP_ZERO |
+ gfp_extra_flags;
+ struct bpf_prog *fp;
+
+ BUG_ON(fp_old == NULL);
+
+ size = round_up(size, PAGE_SIZE);
+ if (size <= fp_old->pages * PAGE_SIZE)
+ return fp_old;
+
+ fp = __vmalloc(size, gfp_flags, PAGE_KERNEL);
+ if (fp != NULL) {
+ memcpy(fp, fp_old, fp_old->pages * PAGE_SIZE);
+ fp->pages = size / PAGE_SIZE;
+
+ /* We keep fp->aux from fp_old around in the new
+ * reallocated structure.
+ */
+ fp_old->aux = NULL;
+ __bpf_prog_free(fp_old);
+ }
+
+ 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);
+
+#ifdef CONFIG_BPF_JIT
+struct bpf_binary_header *
+bpf_jit_binary_alloc(unsigned int proglen, u8 **image_ptr,
+ unsigned int alignment,
+ bpf_jit_fill_hole_t bpf_fill_ill_insns)
+{
+ struct bpf_binary_header *hdr;
+ unsigned int size, hole, start;
+
+ /* Most of BPF filters are really small, but if some of them
+ * fill a page, allow at least 128 extra bytes to insert a
+ * random section of illegal instructions.
+ */
+ size = round_up(proglen + sizeof(*hdr) + 128, PAGE_SIZE);
+ hdr = module_alloc(size);
+ if (hdr == NULL)
+ return NULL;
+
+ /* Fill space with illegal/arch-dep instructions. */
+ bpf_fill_ill_insns(hdr, size);
+
+ hdr->pages = size / PAGE_SIZE;
+ hole = min_t(unsigned int, size - (proglen + sizeof(*hdr)),
+ PAGE_SIZE - sizeof(*hdr));
+ start = (prandom_u32() % hole) & ~(alignment - 1);
+
+ /* Leave a random number of instructions before BPF code. */
+ *image_ptr = &hdr->image[start];
+
+ return hdr;
+}
+
+void bpf_jit_binary_free(struct bpf_binary_header *hdr)
+{
+ module_free(NULL, hdr);
+}
+#endif /* CONFIG_BPF_JIT */
+
/* Base function for offset calculation. Needs to go into .text section,
* therefore keeping it non-static as well; will also be used by JITs
* anyway later on, so do not let the compiler omit it.
@@ -180,6 +284,7 @@ static unsigned int __bpf_prog_run(void *ctx, const struct bpf_insn *insn)
[BPF_LD | BPF_IND | BPF_W] = &&LD_IND_W,
[BPF_LD | BPF_IND | BPF_H] = &&LD_IND_H,
[BPF_LD | BPF_IND | BPF_B] = &&LD_IND_B,
+ [BPF_LD | BPF_IMM | BPF_DW] = &&LD_IMM_DW,
};
void *ptr;
int off;
@@ -239,6 +344,10 @@ select_insn:
ALU64_MOV_K:
DST = IMM;
CONT;
+ LD_IMM_DW:
+ DST = (u64) (u32) insn[0].imm | ((u64) (u32) insn[1].imm) << 32;
+ insn++;
+ CONT;
ALU64_ARSH_X:
(*(s64 *) &DST) >>= SRC;
CONT;
@@ -523,12 +632,26 @@ void bpf_prog_select_runtime(struct bpf_prog *fp)
/* Probe if internal BPF can be JITed */
bpf_int_jit_compile(fp);
+ /* Lock whole bpf_prog as read-only */
+ bpf_prog_lock_ro(fp);
}
EXPORT_SYMBOL_GPL(bpf_prog_select_runtime);
-/* free internal BPF program */
+static void bpf_prog_free_deferred(struct work_struct *work)
+{
+ struct bpf_prog_aux *aux;
+
+ aux = container_of(work, struct bpf_prog_aux, work);
+ bpf_jit_free(aux->prog);
+}
+
+/* Free internal BPF program */
void bpf_prog_free(struct bpf_prog *fp)
{
- bpf_jit_free(fp);
+ struct bpf_prog_aux *aux = fp->aux;
+
+ INIT_WORK(&aux->work, bpf_prog_free_deferred);
+ aux->prog = fp;
+ schedule_work(&aux->work);
}
EXPORT_SYMBOL_GPL(bpf_prog_free);
diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c
new file mode 100644
index 000000000000..ba61c8c16032
--- /dev/null
+++ b/kernel/bpf/syscall.c
@@ -0,0 +1,606 @@
+/* Copyright (c) 2011-2014 PLUMgrid, http://plumgrid.com
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of version 2 of the GNU General Public
+ * License as published by the Free Software Foundation.
+ *
+ * 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.
+ */
+#include <linux/bpf.h>
+#include <linux/syscalls.h>
+#include <linux/slab.h>
+#include <linux/anon_inodes.h>
+#include <linux/file.h>
+#include <linux/license.h>
+#include <linux/filter.h>
+
+static LIST_HEAD(bpf_map_types);
+
+static struct bpf_map *find_and_alloc_map(union bpf_attr *attr)
+{
+ struct bpf_map_type_list *tl;
+ struct bpf_map *map;
+
+ list_for_each_entry(tl, &bpf_map_types, list_node) {
+ if (tl->type == attr->map_type) {
+ map = tl->ops->map_alloc(attr);
+ if (IS_ERR(map))
+ return map;
+ map->ops = tl->ops;
+ map->map_type = attr->map_type;
+ return map;
+ }
+ }
+ return ERR_PTR(-EINVAL);
+}
+
+/* boot time registration of different map implementations */
+void bpf_register_map_type(struct bpf_map_type_list *tl)
+{
+ list_add(&tl->list_node, &bpf_map_types);
+}
+
+/* called from workqueue */
+static void bpf_map_free_deferred(struct work_struct *work)
+{
+ struct bpf_map *map = container_of(work, struct bpf_map, work);
+
+ /* implementation dependent freeing */
+ map->ops->map_free(map);
+}
+
+/* decrement map refcnt and schedule it for freeing via workqueue
+ * (unrelying map implementation ops->map_free() might sleep)
+ */
+void bpf_map_put(struct bpf_map *map)
+{
+ if (atomic_dec_and_test(&map->refcnt)) {
+ INIT_WORK(&map->work, bpf_map_free_deferred);
+ schedule_work(&map->work);
+ }
+}
+
+static int bpf_map_release(struct inode *inode, struct file *filp)
+{
+ struct bpf_map *map = filp->private_data;
+
+ bpf_map_put(map);
+ return 0;
+}
+
+static const struct file_operations bpf_map_fops = {
+ .release = bpf_map_release,
+};
+
+/* helper macro to check that unused fields 'union bpf_attr' are zero */
+#define CHECK_ATTR(CMD) \
+ memchr_inv((void *) &attr->CMD##_LAST_FIELD + \
+ sizeof(attr->CMD##_LAST_FIELD), 0, \
+ sizeof(*attr) - \
+ offsetof(union bpf_attr, CMD##_LAST_FIELD) - \
+ sizeof(attr->CMD##_LAST_FIELD)) != NULL
+
+#define BPF_MAP_CREATE_LAST_FIELD max_entries
+/* called via syscall */
+static int map_create(union bpf_attr *attr)
+{
+ struct bpf_map *map;
+ int err;
+
+ err = CHECK_ATTR(BPF_MAP_CREATE);
+ if (err)
+ return -EINVAL;
+
+ /* find map type and init map: hashtable vs rbtree vs bloom vs ... */
+ map = find_and_alloc_map(attr);
+ if (IS_ERR(map))
+ return PTR_ERR(map);
+
+ atomic_set(&map->refcnt, 1);
+
+ err = anon_inode_getfd("bpf-map", &bpf_map_fops, map, O_RDWR | O_CLOEXEC);
+
+ if (err < 0)
+ /* failed to allocate fd */
+ goto free_map;
+
+ return err;
+
+free_map:
+ map->ops->map_free(map);
+ return err;
+}
+
+/* if error is returned, fd is released.
+ * On success caller should complete fd access with matching fdput()
+ */
+struct bpf_map *bpf_map_get(struct fd f)
+{
+ struct bpf_map *map;
+
+ if (!f.file)
+ return ERR_PTR(-EBADF);
+
+ if (f.file->f_op != &bpf_map_fops) {
+ fdput(f);
+ return ERR_PTR(-EINVAL);
+ }
+
+ map = f.file->private_data;
+
+ return map;
+}
+
+/* helper to convert user pointers passed inside __aligned_u64 fields */
+static void __user *u64_to_ptr(__u64 val)
+{
+ return (void __user *) (unsigned long) val;
+}
+
+/* last field in 'union bpf_attr' used by this command */
+#define BPF_MAP_LOOKUP_ELEM_LAST_FIELD value
+
+static int map_lookup_elem(union bpf_attr *attr)
+{
+ void __user *ukey = u64_to_ptr(attr->key);
+ void __user *uvalue = u64_to_ptr(attr->value);
+ int ufd = attr->map_fd;
+ struct fd f = fdget(ufd);
+ struct bpf_map *map;
+ void *key, *value;
+ int err;
+
+ if (CHECK_ATTR(BPF_MAP_LOOKUP_ELEM))
+ return -EINVAL;
+
+ map = bpf_map_get(f);
+ if (IS_ERR(map))
+ return PTR_ERR(map);
+
+ err = -ENOMEM;
+ key = kmalloc(map->key_size, GFP_USER);
+ if (!key)
+ goto err_put;
+
+ err = -EFAULT;
+ if (copy_from_user(key, ukey, map->key_size) != 0)
+ goto free_key;
+
+ err = -ESRCH;
+ rcu_read_lock();
+ value = map->ops->map_lookup_elem(map, key);
+ if (!value)
+ goto err_unlock;
+
+ err = -EFAULT;
+ if (copy_to_user(uvalue, value, map->value_size) != 0)
+ goto err_unlock;
+
+ err = 0;
+
+err_unlock:
+ rcu_read_unlock();
+free_key:
+ kfree(key);
+err_put:
+ fdput(f);
+ return err;
+}
+
+#define BPF_MAP_UPDATE_ELEM_LAST_FIELD value
+
+static int map_update_elem(union bpf_attr *attr)
+{
+ void __user *ukey = u64_to_ptr(attr->key);
+ void __user *uvalue = u64_to_ptr(attr->value);
+ int ufd = attr->map_fd;
+ struct fd f = fdget(ufd);
+ struct bpf_map *map;
+ void *key, *value;
+ int err;
+
+ if (CHECK_ATTR(BPF_MAP_UPDATE_ELEM))
+ return -EINVAL;
+
+ map = bpf_map_get(f);
+ if (IS_ERR(map))
+ return PTR_ERR(map);
+
+ err = -ENOMEM;
+ key = kmalloc(map->key_size, GFP_USER);
+ if (!key)
+ goto err_put;
+
+ err = -EFAULT;
+ if (copy_from_user(key, ukey, map->key_size) != 0)
+ goto free_key;
+
+ err = -ENOMEM;
+ value = kmalloc(map->value_size, GFP_USER);
+ if (!value)
+ goto free_key;
+
+ err = -EFAULT;
+ if (copy_from_user(value, uvalue, map->value_size) != 0)
+ goto free_value;
+
+ /* eBPF program that use maps are running under rcu_read_lock(),
+ * therefore all map accessors rely on this fact, so do the same here
+ */
+ rcu_read_lock();
+ err = map->ops->map_update_elem(map, key, value);
+ rcu_read_unlock();
+
+free_value:
+ kfree(value);
+free_key:
+ kfree(key);
+err_put:
+ fdput(f);
+ return err;
+}
+
+#define BPF_MAP_DELETE_ELEM_LAST_FIELD key
+
+static int map_delete_elem(union bpf_attr *attr)
+{
+ void __user *ukey = u64_to_ptr(attr->key);
+ int ufd = attr->map_fd;
+ struct fd f = fdget(ufd);
+ struct bpf_map *map;
+ void *key;
+ int err;
+
+ if (CHECK_ATTR(BPF_MAP_DELETE_ELEM))
+ return -EINVAL;
+
+ map = bpf_map_get(f);
+ if (IS_ERR(map))
+ return PTR_ERR(map);
+
+ err = -ENOMEM;
+ key = kmalloc(map->key_size, GFP_USER);
+ if (!key)
+ goto err_put;
+
+ err = -EFAULT;
+ if (copy_from_user(key, ukey, map->key_size) != 0)
+ goto free_key;
+
+ rcu_read_lock();
+ err = map->ops->map_delete_elem(map, key);
+ rcu_read_unlock();
+
+free_key:
+ kfree(key);
+err_put:
+ fdput(f);
+ return err;
+}
+
+/* last field in 'union bpf_attr' used by this command */
+#define BPF_MAP_GET_NEXT_KEY_LAST_FIELD next_key
+
+static int map_get_next_key(union bpf_attr *attr)
+{
+ void __user *ukey = u64_to_ptr(attr->key);
+ void __user *unext_key = u64_to_ptr(attr->next_key);
+ int ufd = attr->map_fd;
+ struct fd f = fdget(ufd);
+ struct bpf_map *map;
+ void *key, *next_key;
+ int err;
+
+ if (CHECK_ATTR(BPF_MAP_GET_NEXT_KEY))
+ return -EINVAL;
+
+ map = bpf_map_get(f);
+ if (IS_ERR(map))
+ return PTR_ERR(map);
+
+ err = -ENOMEM;
+ key = kmalloc(map->key_size, GFP_USER);
+ if (!key)
+ goto err_put;
+
+ err = -EFAULT;
+ if (copy_from_user(key, ukey, map->key_size) != 0)
+ goto free_key;
+
+ err = -ENOMEM;
+ next_key = kmalloc(map->key_size, GFP_USER);
+ if (!next_key)
+ goto free_key;
+
+ rcu_read_lock();
+ err = map->ops->map_get_next_key(map, key, next_key);
+ rcu_read_unlock();
+ if (err)
+ goto free_next_key;
+
+ err = -EFAULT;
+ if (copy_to_user(unext_key, next_key, map->key_size) != 0)
+ goto free_next_key;
+
+ err = 0;
+
+free_next_key:
+ kfree(next_key);
+free_key:
+ kfree(key);
+err_put:
+ fdput(f);
+ return err;
+}
+
+static LIST_HEAD(bpf_prog_types);
+
+static int find_prog_type(enum bpf_prog_type type, struct bpf_prog *prog)
+{
+ struct bpf_prog_type_list *tl;
+
+ list_for_each_entry(tl, &bpf_prog_types, list_node) {
+ if (tl->type == type) {
+ prog->aux->ops = tl->ops;
+ prog->aux->prog_type = type;
+ return 0;
+ }
+ }
+ return -EINVAL;
+}
+
+void bpf_register_prog_type(struct bpf_prog_type_list *tl)
+{
+ list_add(&tl->list_node, &bpf_prog_types);
+}
+
+/* fixup insn->imm field of bpf_call instructions:
+ * if (insn->imm == BPF_FUNC_map_lookup_elem)
+ * insn->imm = bpf_map_lookup_elem - __bpf_call_base;
+ * else if (insn->imm == BPF_FUNC_map_update_elem)
+ * insn->imm = bpf_map_update_elem - __bpf_call_base;
+ * else ...
+ *
+ * this function is called after eBPF program passed verification
+ */
+static void fixup_bpf_calls(struct bpf_prog *prog)
+{
+ const struct bpf_func_proto *fn;
+ int i;
+
+ for (i = 0; i < prog->len; i++) {
+ struct bpf_insn *insn = &prog->insnsi[i];
+
+ if (insn->code == (BPF_JMP | BPF_CALL)) {
+ /* we reach here when program has bpf_call instructions
+ * and it passed bpf_check(), means that
+ * ops->get_func_proto must have been supplied, check it
+ */
+ BUG_ON(!prog->aux->ops->get_func_proto);
+
+ fn = prog->aux->ops->get_func_proto(insn->imm);
+ /* all functions that have prototype and verifier allowed
+ * programs to call them, must be real in-kernel functions
+ */
+ BUG_ON(!fn->func);
+ insn->imm = fn->func - __bpf_call_base;
+ }
+ }
+}
+
+/* drop refcnt on maps used by eBPF program and free auxilary data */
+static void free_used_maps(struct bpf_prog_aux *aux)
+{
+ int i;
+
+ for (i = 0; i < aux->used_map_cnt; i++)
+ bpf_map_put(aux->used_maps[i]);
+
+ kfree(aux->used_maps);
+}
+
+void bpf_prog_put(struct bpf_prog *prog)
+{
+ if (atomic_dec_and_test(&prog->aux->refcnt)) {
+ free_used_maps(prog->aux);
+ bpf_prog_free(prog);
+ }
+}
+
+static int bpf_prog_release(struct inode *inode, struct file *filp)
+{
+ struct bpf_prog *prog = filp->private_data;
+
+ bpf_prog_put(prog);
+ return 0;
+}
+
+static const struct file_operations bpf_prog_fops = {
+ .release = bpf_prog_release,
+};
+
+static struct bpf_prog *get_prog(struct fd f)
+{
+ struct bpf_prog *prog;
+
+ if (!f.file)
+ return ERR_PTR(-EBADF);
+
+ if (f.file->f_op != &bpf_prog_fops) {
+ fdput(f);
+ return ERR_PTR(-EINVAL);
+ }
+
+ prog = f.file->private_data;
+
+ return prog;
+}
+
+/* called by sockets/tracing/seccomp before attaching program to an event
+ * pairs with bpf_prog_put()
+ */
+struct bpf_prog *bpf_prog_get(u32 ufd)
+{
+ struct fd f = fdget(ufd);
+ struct bpf_prog *prog;
+
+ prog = get_prog(f);
+
+ if (IS_ERR(prog))
+ return prog;
+
+ atomic_inc(&prog->aux->refcnt);
+ fdput(f);
+ return prog;
+}
+
+/* last field in 'union bpf_attr' used by this command */
+#define BPF_PROG_LOAD_LAST_FIELD log_buf
+
+static int bpf_prog_load(union bpf_attr *attr)
+{
+ enum bpf_prog_type type = attr->prog_type;
+ struct bpf_prog *prog;
+ int err;
+ char license[128];
+ bool is_gpl;
+
+ if (CHECK_ATTR(BPF_PROG_LOAD))
+ return -EINVAL;
+
+ /* copy eBPF program license from user space */
+ if (strncpy_from_user(license, u64_to_ptr(attr->license),
+ sizeof(license) - 1) < 0)
+ return -EFAULT;
+ license[sizeof(license) - 1] = 0;
+
+ /* eBPF programs must be GPL compatible to use GPL-ed functions */
+ is_gpl = license_is_gpl_compatible(license);
+
+ if (attr->insn_cnt >= BPF_MAXINSNS)
+ return -EINVAL;
+
+ /* plain bpf_prog allocation */
+ prog = bpf_prog_alloc(bpf_prog_size(attr->insn_cnt), GFP_USER);
+ if (!prog)
+ return -ENOMEM;
+
+ prog->len = attr->insn_cnt;
+
+ err = -EFAULT;
+ if (copy_from_user(prog->insns, u64_to_ptr(attr->insns),
+ prog->len * sizeof(struct bpf_insn)) != 0)
+ goto free_prog;
+
+ prog->orig_prog = NULL;
+ prog->jited = false;
+
+ atomic_set(&prog->aux->refcnt, 1);
+ prog->aux->is_gpl_compatible = is_gpl;
+
+ /* find program type: socket_filter vs tracing_filter */
+ err = find_prog_type(type, prog);
+ if (err < 0)
+ goto free_prog;
+
+ /* run eBPF verifier */
+ err = bpf_check(prog, attr);
+
+ if (err < 0)
+ goto free_used_maps;
+
+ /* fixup BPF_CALL->imm field */
+ fixup_bpf_calls(prog);
+
+ /* eBPF program is ready to be JITed */
+ bpf_prog_select_runtime(prog);
+
+ err = anon_inode_getfd("bpf-prog", &bpf_prog_fops, prog, O_RDWR | O_CLOEXEC);
+
+ if (err < 0)
+ /* failed to allocate fd */
+ goto free_used_maps;
+
+ return err;
+
+free_used_maps:
+ free_used_maps(prog->aux);
+free_prog:
+ bpf_prog_free(prog);
+ return err;
+}
+
+SYSCALL_DEFINE3(bpf, int, cmd, union bpf_attr __user *, uattr, unsigned int, size)
+{
+ union bpf_attr attr = {};
+ int err;
+
+ /* the syscall is limited to root temporarily. This restriction will be
+ * lifted when security audit is clean. Note that eBPF+tracing must have
+ * this restriction, since it may pass kernel data to user space
+ */
+ if (!capable(CAP_SYS_ADMIN))
+ return -EPERM;
+
+ if (!access_ok(VERIFY_READ, uattr, 1))
+ return -EFAULT;
+
+ if (size > PAGE_SIZE) /* silly large */
+ return -E2BIG;
+
+ /* If we're handed a bigger struct than we know of,
+ * ensure all the unknown bits are 0 - i.e. new
+ * user-space does not rely on any kernel feature
+ * extensions we dont know about yet.
+ */
+ if (size > sizeof(attr)) {
+ unsigned char __user *addr;
+ unsigned char __user *end;
+ unsigned char val;
+
+ addr = (void __user *)uattr + sizeof(attr);
+ end = (void __user *)uattr + size;
+
+ for (; addr < end; addr++) {
+ err = get_user(val, addr);
+ if (err)
+ return err;
+ if (val)
+ return -E2BIG;
+ }
+ size = sizeof(attr);
+ }
+
+ /* copy attributes from user space, may be less than sizeof(bpf_attr) */
+ if (copy_from_user(&attr, uattr, size) != 0)
+ return -EFAULT;
+
+ switch (cmd) {
+ case BPF_MAP_CREATE:
+ err = map_create(&attr);
+ break;
+ case BPF_MAP_LOOKUP_ELEM:
+ err = map_lookup_elem(&attr);
+ break;
+ case BPF_MAP_UPDATE_ELEM:
+ err = map_update_elem(&attr);
+ break;
+ case BPF_MAP_DELETE_ELEM:
+ err = map_delete_elem(&attr);
+ break;
+ case BPF_MAP_GET_NEXT_KEY:
+ err = map_get_next_key(&attr);
+ break;
+ case BPF_PROG_LOAD:
+ err = bpf_prog_load(&attr);
+ break;
+ default:
+ err = -EINVAL;
+ break;
+ }
+
+ return err;
+}
diff --git a/kernel/bpf/test_stub.c b/kernel/bpf/test_stub.c
new file mode 100644
index 000000000000..fcaddff4003e
--- /dev/null
+++ b/kernel/bpf/test_stub.c
@@ -0,0 +1,116 @@
+/* Copyright (c) 2011-2014 PLUMgrid, http://plumgrid.com
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of version 2 of the GNU General Public
+ * License as published by the Free Software Foundation.
+ */
+#include <linux/kernel.h>
+#include <linux/types.h>
+#include <linux/slab.h>
+#include <linux/err.h>
+#include <linux/bpf.h>
+
+/* test stubs for BPF_MAP_TYPE_UNSPEC and for BPF_PROG_TYPE_UNSPEC
+ * to be used by user space verifier testsuite
+ */
+struct bpf_context {
+ u64 arg1;
+ u64 arg2;
+};
+
+static u64 test_func(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5)
+{
+ return 0;
+}
+
+static struct bpf_func_proto test_funcs[] = {
+ [BPF_FUNC_unspec] = {
+ .func = test_func,
+ .gpl_only = true,
+ .ret_type = RET_PTR_TO_MAP_VALUE_OR_NULL,
+ .arg1_type = ARG_CONST_MAP_PTR,
+ .arg2_type = ARG_PTR_TO_MAP_KEY,
+ },
+};
+
+static const struct bpf_func_proto *test_func_proto(enum bpf_func_id func_id)
+{
+ if (func_id < 0 || func_id >= ARRAY_SIZE(test_funcs))
+ return NULL;
+ return &test_funcs[func_id];
+}
+
+static const struct bpf_context_access {
+ int size;
+ enum bpf_access_type type;
+} test_ctx_access[] = {
+ [offsetof(struct bpf_context, arg1)] = {
+ FIELD_SIZEOF(struct bpf_context, arg1),
+ BPF_READ
+ },
+ [offsetof(struct bpf_context, arg2)] = {
+ FIELD_SIZEOF(struct bpf_context, arg2),
+ BPF_READ
+ },
+};
+
+static bool test_is_valid_access(int off, int size, enum bpf_access_type type)
+{
+ const struct bpf_context_access *access;
+
+ if (off < 0 || off >= ARRAY_SIZE(test_ctx_access))
+ return false;
+
+ access = &test_ctx_access[off];
+ if (access->size == size && (access->type & type))
+ return true;
+
+ return false;
+}
+
+static struct bpf_verifier_ops test_ops = {
+ .get_func_proto = test_func_proto,
+ .is_valid_access = test_is_valid_access,
+};
+
+static struct bpf_prog_type_list tl_prog = {
+ .ops = &test_ops,
+ .type = BPF_PROG_TYPE_UNSPEC,
+};
+
+static struct bpf_map *test_map_alloc(union bpf_attr *attr)
+{
+ struct bpf_map *map;
+
+ map = kzalloc(sizeof(*map), GFP_USER);
+ if (!map)
+ return ERR_PTR(-ENOMEM);
+
+ map->key_size = attr->key_size;
+ map->value_size = attr->value_size;
+ map->max_entries = attr->max_entries;
+ return map;
+}
+
+static void test_map_free(struct bpf_map *map)
+{
+ kfree(map);
+}
+
+static struct bpf_map_ops test_map_ops = {
+ .map_alloc = test_map_alloc,
+ .map_free = test_map_free,
+};
+
+static struct bpf_map_type_list tl_map = {
+ .ops = &test_map_ops,
+ .type = BPF_MAP_TYPE_UNSPEC,
+};
+
+static int __init register_test_ops(void)
+{
+ bpf_register_map_type(&tl_map);
+ bpf_register_prog_type(&tl_prog);
+ return 0;
+}
+late_initcall(register_test_ops);
diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
new file mode 100644
index 000000000000..801f5f3b9307
--- /dev/null
+++ b/kernel/bpf/verifier.c
@@ -0,0 +1,1923 @@
+/* Copyright (c) 2011-2014 PLUMgrid, http://plumgrid.com
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of version 2 of the GNU General Public
+ * License as published by the Free Software Foundation.
+ *
+ * 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.
+ */
+#include <linux/kernel.h>
+#include <linux/types.h>
+#include <linux/slab.h>
+#include <linux/bpf.h>
+#include <linux/filter.h>
+#include <net/netlink.h>
+#include <linux/file.h>
+#include <linux/vmalloc.h>
+
+/* bpf_check() is a static code analyzer that walks eBPF program
+ * instruction by instruction and updates register/stack state.
+ * All paths of conditional branches are analyzed until 'bpf_exit' insn.
+ *
+ * The first pass is depth-first-search to check that the program is a DAG.
+ * It rejects the following programs:
+ * - larger than BPF_MAXINSNS insns
+ * - if loop is present (detected via back-edge)
+ * - unreachable insns exist (shouldn't be a forest. program = one function)
+ * - out of bounds or malformed jumps
+ * The second pass is all possible path descent from the 1st insn.
+ * Since it's analyzing all pathes through the program, the length of the
+ * analysis is limited to 32k insn, which may be hit even if total number of
+ * insn is less then 4K, but there are too many branches that change stack/regs.
+ * Number of 'branches to be analyzed' is limited to 1k
+ *
+ * On entry to each instruction, each register has a type, and the instruction
+ * changes the types of the registers depending on instruction semantics.
+ * If instruction is BPF_MOV64_REG(BPF_REG_1, BPF_REG_5), then type of R5 is
+ * copied to R1.
+ *
+ * All registers are 64-bit.
+ * R0 - return register
+ * R1-R5 argument passing registers
+ * R6-R9 callee saved registers
+ * R10 - frame pointer read-only
+ *
+ * At the start of BPF program the register R1 contains a pointer to bpf_context
+ * and has type PTR_TO_CTX.
+ *
+ * Verifier tracks arithmetic operations on pointers in case:
+ * BPF_MOV64_REG(BPF_REG_1, BPF_REG_10),
+ * BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, -20),
+ * 1st insn copies R10 (which has FRAME_PTR) type into R1
+ * and 2nd arithmetic instruction is pattern matched to recognize
+ * that it wants to construct a pointer to some element within stack.
+ * So after 2nd insn, the register R1 has type PTR_TO_STACK
+ * (and -20 constant is saved for further stack bounds checking).
+ * Meaning that this reg is a pointer to stack plus known immediate constant.
+ *
+ * Most of the time the registers have UNKNOWN_VALUE type, which
+ * means the register has some value, but it's not a valid pointer.
+ * (like pointer plus pointer becomes UNKNOWN_VALUE type)
+ *
+ * When verifier sees load or store instructions the type of base register
+ * can be: PTR_TO_MAP_VALUE, PTR_TO_CTX, FRAME_PTR. These are three pointer
+ * types recognized by check_mem_access() function.
+ *
+ * PTR_TO_MAP_VALUE means that this register is pointing to 'map element value'
+ * and the range of [ptr, ptr + map's value_size) is accessible.
+ *
+ * registers used to pass values to function calls are checked against
+ * function argument constraints.
+ *
+ * ARG_PTR_TO_MAP_KEY is one of such argument constraints.
+ * It means that the register type passed to this function must be
+ * PTR_TO_STACK and it will be used inside the function as
+ * 'pointer to map element key'
+ *
+ * For example the argument constraints for bpf_map_lookup_elem():
+ * .ret_type = RET_PTR_TO_MAP_VALUE_OR_NULL,
+ * .arg1_type = ARG_CONST_MAP_PTR,
+ * .arg2_type = ARG_PTR_TO_MAP_KEY,
+ *
+ * ret_type says that this function returns 'pointer to map elem value or null'
+ * function expects 1st argument to be a const pointer to 'struct bpf_map' and
+ * 2nd argument should be a pointer to stack, which will be used inside
+ * the helper function as a pointer to map element key.
+ *
+ * On the kernel side the helper function looks like:
+ * u64 bpf_map_lookup_elem(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5)
+ * {
+ * struct bpf_map *map = (struct bpf_map *) (unsigned long) r1;
+ * void *key = (void *) (unsigned long) r2;
+ * void *value;
+ *
+ * here kernel can access 'key' and 'map' pointers safely, knowing that
+ * [key, key + map->key_size) bytes are valid and were initialized on
+ * the stack of eBPF program.
+ * }
+ *
+ * Corresponding eBPF program may look like:
+ * BPF_MOV64_REG(BPF_REG_2, BPF_REG_10), // after this insn R2 type is FRAME_PTR
+ * BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -4), // after this insn R2 type is PTR_TO_STACK
+ * BPF_LD_MAP_FD(BPF_REG_1, map_fd), // after this insn R1 type is CONST_PTR_TO_MAP
+ * BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_map_lookup_elem),
+ * here verifier looks at prototype of map_lookup_elem() and sees:
+ * .arg1_type == ARG_CONST_MAP_PTR and R1->type == CONST_PTR_TO_MAP, which is ok,
+ * Now verifier knows that this map has key of R1->map_ptr->key_size bytes
+ *
+ * Then .arg2_type == ARG_PTR_TO_MAP_KEY and R2->type == PTR_TO_STACK, ok so far,
+ * Now verifier checks that [R2, R2 + map's key_size) are within stack limits
+ * and were initialized prior to this call.
+ * If it's ok, then verifier allows this BPF_CALL insn and looks at
+ * .ret_type which is RET_PTR_TO_MAP_VALUE_OR_NULL, so it sets
+ * R0->type = PTR_TO_MAP_VALUE_OR_NULL which means bpf_map_lookup_elem() function
+ * returns ether pointer to map value or NULL.
+ *
+ * When type PTR_TO_MAP_VALUE_OR_NULL passes through 'if (reg != 0) goto +off'
+ * insn, the register holding that pointer in the true branch changes state to
+ * PTR_TO_MAP_VALUE and the same register changes state to CONST_IMM in the false
+ * branch. See check_cond_jmp_op().
+ *
+ * After the call R0 is set to return type of the function and registers R1-R5
+ * are set to NOT_INIT to indicate that they are no longer readable.
+ */
+
+/* types of values stored in eBPF registers */
+enum bpf_reg_type {
+ NOT_INIT = 0, /* nothing was written into register */
+ UNKNOWN_VALUE, /* reg doesn't contain a valid pointer */
+ PTR_TO_CTX, /* reg points to bpf_context */
+ CONST_PTR_TO_MAP, /* reg points to struct bpf_map */
+ PTR_TO_MAP_VALUE, /* reg points to map element value */
+ PTR_TO_MAP_VALUE_OR_NULL,/* points to map elem value or NULL */
+ FRAME_PTR, /* reg == frame_pointer */
+ PTR_TO_STACK, /* reg == frame_pointer + imm */
+ CONST_IMM, /* constant integer value */
+};
+
+struct reg_state {
+ enum bpf_reg_type type;
+ union {
+ /* valid when type == CONST_IMM | PTR_TO_STACK */
+ int imm;
+
+ /* valid when type == CONST_PTR_TO_MAP | PTR_TO_MAP_VALUE |
+ * PTR_TO_MAP_VALUE_OR_NULL
+ */
+ struct bpf_map *map_ptr;
+ };
+};
+
+enum bpf_stack_slot_type {
+ STACK_INVALID, /* nothing was stored in this stack slot */
+ STACK_SPILL, /* 1st byte of register spilled into stack */
+ STACK_SPILL_PART, /* other 7 bytes of register spill */
+ STACK_MISC /* BPF program wrote some data into this slot */
+};
+
+struct bpf_stack_slot {
+ enum bpf_stack_slot_type stype;
+ struct reg_state reg_st;
+};
+
+/* state of the program:
+ * type of all registers and stack info
+ */
+struct verifier_state {
+ struct reg_state regs[MAX_BPF_REG];
+ struct bpf_stack_slot stack[MAX_BPF_STACK];
+};
+
+/* linked list of verifier states used to prune search */
+struct verifier_state_list {
+ struct verifier_state state;
+ struct verifier_state_list *next;
+};
+
+/* verifier_state + insn_idx are pushed to stack when branch is encountered */
+struct verifier_stack_elem {
+ /* verifer state is 'st'
+ * before processing instruction 'insn_idx'
+ * and after processing instruction 'prev_insn_idx'
+ */
+ struct verifier_state st;
+ int insn_idx;
+ int prev_insn_idx;
+ struct verifier_stack_elem *next;
+};
+
+#define MAX_USED_MAPS 64 /* max number of maps accessed by one eBPF program */
+
+/* single container for all structs
+ * one verifier_env per bpf_check() call
+ */
+struct verifier_env {
+ struct bpf_prog *prog; /* eBPF program being verified */
+ struct verifier_stack_elem *head; /* stack of verifier states to be processed */
+ int stack_size; /* number of states to be processed */
+ struct verifier_state cur_state; /* current verifier state */
+ struct verifier_state_list **explored_states; /* search pruning optimization */
+ struct bpf_map *used_maps[MAX_USED_MAPS]; /* array of map's used by eBPF program */
+ u32 used_map_cnt; /* number of used maps */
+};
+
+/* verbose verifier prints what it's seeing
+ * bpf_check() is called under lock, so no race to access these global vars
+ */
+static u32 log_level, log_size, log_len;
+static char *log_buf;
+
+static DEFINE_MUTEX(bpf_verifier_lock);
+
+/* log_level controls verbosity level of eBPF verifier.
+ * verbose() is used to dump the verification trace to the log, so the user
+ * can figure out what's wrong with the program
+ */
+static void verbose(const char *fmt, ...)
+{
+ va_list args;
+
+ if (log_level == 0 || log_len >= log_size - 1)
+ return;
+
+ va_start(args, fmt);
+ log_len += vscnprintf(log_buf + log_len, log_size - log_len, fmt, args);
+ va_end(args);
+}
+
+/* string representation of 'enum bpf_reg_type' */
+static const char * const reg_type_str[] = {
+ [NOT_INIT] = "?",
+ [UNKNOWN_VALUE] = "inv",
+ [PTR_TO_CTX] = "ctx",
+ [CONST_PTR_TO_MAP] = "map_ptr",
+ [PTR_TO_MAP_VALUE] = "map_value",
+ [PTR_TO_MAP_VALUE_OR_NULL] = "map_value_or_null",
+ [FRAME_PTR] = "fp",
+ [PTR_TO_STACK] = "fp",
+ [CONST_IMM] = "imm",
+};
+
+static void print_verifier_state(struct verifier_env *env)
+{
+ enum bpf_reg_type t;
+ int i;
+
+ for (i = 0; i < MAX_BPF_REG; i++) {
+ t = env->cur_state.regs[i].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);
+ 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);
+ }
+ for (i = 0; i < MAX_BPF_STACK; i++) {
+ if (env->cur_state.stack[i].stype == STACK_SPILL)
+ verbose(" fp%d=%s", -MAX_BPF_STACK + i,
+ reg_type_str[env->cur_state.stack[i].reg_st.type]);
+ }
+ verbose("\n");
+}
+
+static const char *const bpf_class_string[] = {
+ [BPF_LD] = "ld",
+ [BPF_LDX] = "ldx",
+ [BPF_ST] = "st",
+ [BPF_STX] = "stx",
+ [BPF_ALU] = "alu",
+ [BPF_JMP] = "jmp",
+ [BPF_RET] = "BUG",
+ [BPF_ALU64] = "alu64",
+};
+
+static const char *const bpf_alu_string[] = {
+ [BPF_ADD >> 4] = "+=",
+ [BPF_SUB >> 4] = "-=",
+ [BPF_MUL >> 4] = "*=",
+ [BPF_DIV >> 4] = "/=",
+ [BPF_OR >> 4] = "|=",
+ [BPF_AND >> 4] = "&=",
+ [BPF_LSH >> 4] = "<<=",
+ [BPF_RSH >> 4] = ">>=",
+ [BPF_NEG >> 4] = "neg",
+ [BPF_MOD >> 4] = "%=",
+ [BPF_XOR >> 4] = "^=",
+ [BPF_MOV >> 4] = "=",
+ [BPF_ARSH >> 4] = "s>>=",
+ [BPF_END >> 4] = "endian",
+};
+
+static const char *const bpf_ldst_string[] = {
+ [BPF_W >> 3] = "u32",
+ [BPF_H >> 3] = "u16",
+ [BPF_B >> 3] = "u8",
+ [BPF_DW >> 3] = "u64",
+};
+
+static const char *const bpf_jmp_string[] = {
+ [BPF_JA >> 4] = "jmp",
+ [BPF_JEQ >> 4] = "==",
+ [BPF_JGT >> 4] = ">",
+ [BPF_JGE >> 4] = ">=",
+ [BPF_JSET >> 4] = "&",
+ [BPF_JNE >> 4] = "!=",
+ [BPF_JSGT >> 4] = "s>",
+ [BPF_JSGE >> 4] = "s>=",
+ [BPF_CALL >> 4] = "call",
+ [BPF_EXIT >> 4] = "exit",
+};
+
+static void print_bpf_insn(struct bpf_insn *insn)
+{
+ u8 class = BPF_CLASS(insn->code);
+
+ if (class == BPF_ALU || class == BPF_ALU64) {
+ if (BPF_SRC(insn->code) == BPF_X)
+ verbose("(%02x) %sr%d %s %sr%d\n",
+ insn->code, class == BPF_ALU ? "(u32) " : "",
+ insn->dst_reg,
+ bpf_alu_string[BPF_OP(insn->code) >> 4],
+ class == BPF_ALU ? "(u32) " : "",
+ insn->src_reg);
+ else
+ verbose("(%02x) %sr%d %s %s%d\n",
+ insn->code, class == BPF_ALU ? "(u32) " : "",
+ insn->dst_reg,
+ bpf_alu_string[BPF_OP(insn->code) >> 4],
+ class == BPF_ALU ? "(u32) " : "",
+ insn->imm);
+ } else if (class == BPF_STX) {
+ if (BPF_MODE(insn->code) == BPF_MEM)
+ verbose("(%02x) *(%s *)(r%d %+d) = r%d\n",
+ insn->code,
+ bpf_ldst_string[BPF_SIZE(insn->code) >> 3],
+ insn->dst_reg,
+ insn->off, insn->src_reg);
+ else if (BPF_MODE(insn->code) == BPF_XADD)
+ verbose("(%02x) lock *(%s *)(r%d %+d) += r%d\n",
+ insn->code,
+ bpf_ldst_string[BPF_SIZE(insn->code) >> 3],
+ insn->dst_reg, insn->off,
+ insn->src_reg);
+ else
+ verbose("BUG_%02x\n", insn->code);
+ } else if (class == BPF_ST) {
+ if (BPF_MODE(insn->code) != BPF_MEM) {
+ verbose("BUG_st_%02x\n", insn->code);
+ return;
+ }
+ verbose("(%02x) *(%s *)(r%d %+d) = %d\n",
+ insn->code,
+ bpf_ldst_string[BPF_SIZE(insn->code) >> 3],
+ insn->dst_reg,
+ insn->off, insn->imm);
+ } else if (class == BPF_LDX) {
+ if (BPF_MODE(insn->code) != BPF_MEM) {
+ verbose("BUG_ldx_%02x\n", insn->code);
+ return;
+ }
+ verbose("(%02x) r%d = *(%s *)(r%d %+d)\n",
+ insn->code, insn->dst_reg,
+ bpf_ldst_string[BPF_SIZE(insn->code) >> 3],
+ insn->src_reg, insn->off);
+ } else if (class == BPF_LD) {
+ if (BPF_MODE(insn->code) == BPF_ABS) {
+ verbose("(%02x) r0 = *(%s *)skb[%d]\n",
+ insn->code,
+ bpf_ldst_string[BPF_SIZE(insn->code) >> 3],
+ insn->imm);
+ } else if (BPF_MODE(insn->code) == BPF_IND) {
+ verbose("(%02x) r0 = *(%s *)skb[r%d + %d]\n",
+ insn->code,
+ bpf_ldst_string[BPF_SIZE(insn->code) >> 3],
+ insn->src_reg, insn->imm);
+ } else if (BPF_MODE(insn->code) == BPF_IMM) {
+ verbose("(%02x) r%d = 0x%x\n",
+ insn->code, insn->dst_reg, insn->imm);
+ } else {
+ verbose("BUG_ld_%02x\n", insn->code);
+ return;
+ }
+ } else if (class == BPF_JMP) {
+ u8 opcode = BPF_OP(insn->code);
+
+ if (opcode == BPF_CALL) {
+ verbose("(%02x) call %d\n", insn->code, insn->imm);
+ } else if (insn->code == (BPF_JMP | BPF_JA)) {
+ verbose("(%02x) goto pc%+d\n",
+ insn->code, insn->off);
+ } else if (insn->code == (BPF_JMP | BPF_EXIT)) {
+ verbose("(%02x) exit\n", insn->code);
+ } else if (BPF_SRC(insn->code) == BPF_X) {
+ verbose("(%02x) if r%d %s r%d goto pc%+d\n",
+ insn->code, insn->dst_reg,
+ bpf_jmp_string[BPF_OP(insn->code) >> 4],
+ insn->src_reg, insn->off);
+ } else {
+ verbose("(%02x) if r%d %s 0x%x goto pc%+d\n",
+ insn->code, insn->dst_reg,
+ bpf_jmp_string[BPF_OP(insn->code) >> 4],
+ insn->imm, insn->off);
+ }
+ } else {
+ verbose("(%02x) %s\n", insn->code, bpf_class_string[class]);
+ }
+}
+
+static int pop_stack(struct verifier_env *env, int *prev_insn_idx)
+{
+ struct verifier_stack_elem *elem;
+ int insn_idx;
+
+ if (env->head == NULL)
+ return -1;
+
+ memcpy(&env->cur_state, &env->head->st, sizeof(env->cur_state));
+ insn_idx = env->head->insn_idx;
+ if (prev_insn_idx)
+ *prev_insn_idx = env->head->prev_insn_idx;
+ elem = env->head->next;
+ kfree(env->head);
+ env->head = elem;
+ env->stack_size--;
+ return insn_idx;
+}
+
+static struct verifier_state *push_stack(struct verifier_env *env, int insn_idx,
+ int prev_insn_idx)
+{
+ struct verifier_stack_elem *elem;
+
+ elem = kmalloc(sizeof(struct verifier_stack_elem), GFP_KERNEL);
+ if (!elem)
+ goto err;
+
+ memcpy(&elem->st, &env->cur_state, sizeof(env->cur_state));
+ elem->insn_idx = insn_idx;
+ elem->prev_insn_idx = prev_insn_idx;
+ elem->next = env->head;
+ env->head = elem;
+ env->stack_size++;
+ if (env->stack_size > 1024) {
+ verbose("BPF program is too complex\n");
+ goto err;
+ }
+ return &elem->st;
+err:
+ /* pop all elements and return */
+ while (pop_stack(env, NULL) >= 0);
+ return NULL;
+}
+
+#define CALLER_SAVED_REGS 6
+static const int caller_saved[CALLER_SAVED_REGS] = {
+ BPF_REG_0, BPF_REG_1, BPF_REG_2, BPF_REG_3, BPF_REG_4, BPF_REG_5
+};
+
+static void init_reg_state(struct reg_state *regs)
+{
+ int i;
+
+ for (i = 0; i < MAX_BPF_REG; i++) {
+ regs[i].type = NOT_INIT;
+ regs[i].imm = 0;
+ regs[i].map_ptr = NULL;
+ }
+
+ /* frame pointer */
+ regs[BPF_REG_FP].type = FRAME_PTR;
+
+ /* 1st arg to a function */
+ regs[BPF_REG_1].type = PTR_TO_CTX;
+}
+
+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 {
+ SRC_OP, /* register is used as source operand */
+ DST_OP, /* register is used as destination operand */
+ DST_OP_NO_MARK /* same as above, check only, don't mark */
+};
+
+static int check_reg_arg(struct reg_state *regs, u32 regno,
+ enum reg_arg_type t)
+{
+ if (regno >= MAX_BPF_REG) {
+ verbose("R%d is invalid\n", regno);
+ return -EINVAL;
+ }
+
+ if (t == SRC_OP) {
+ /* check whether register used as source operand can be read */
+ if (regs[regno].type == NOT_INIT) {
+ verbose("R%d !read_ok\n", regno);
+ return -EACCES;
+ }
+ } else {
+ /* check whether register used as dest operand can be written to */
+ if (regno == BPF_REG_FP) {
+ verbose("frame pointer is read only\n");
+ return -EACCES;
+ }
+ if (t == DST_OP)
+ mark_reg_unknown_value(regs, regno);
+ }
+ return 0;
+}
+
+static int bpf_size_to_bytes(int bpf_size)
+{
+ if (bpf_size == BPF_W)
+ return 4;
+ else if (bpf_size == BPF_H)
+ return 2;
+ else if (bpf_size == BPF_B)
+ return 1;
+ else if (bpf_size == BPF_DW)
+ return 8;
+ else
+ return -EINVAL;
+}
+
+/* check_stack_read/write functions track spill/fill of registers,
+ * stack boundary and alignment are checked in check_mem_access()
+ */
+static int check_stack_write(struct verifier_state *state, int off, int size,
+ int value_regno)
+{
+ struct bpf_stack_slot *slot;
+ int i;
+
+ if (value_regno >= 0 &&
+ (state->regs[value_regno].type == PTR_TO_MAP_VALUE ||
+ state->regs[value_regno].type == PTR_TO_STACK ||
+ state->regs[value_regno].type == PTR_TO_CTX)) {
+
+ /* register containing pointer is being spilled into stack */
+ if (size != 8) {
+ verbose("invalid size of register spill\n");
+ return -EACCES;
+ }
+
+ slot = &state->stack[MAX_BPF_STACK + off];
+ slot->stype = STACK_SPILL;
+ /* save register state */
+ slot->reg_st = state->regs[value_regno];
+ for (i = 1; i < 8; i++) {
+ slot = &state->stack[MAX_BPF_STACK + off + i];
+ slot->stype = STACK_SPILL_PART;
+ slot->reg_st.type = UNKNOWN_VALUE;
+ slot->reg_st.map_ptr = NULL;
+ }
+ } else {
+
+ /* regular write of data into stack */
+ for (i = 0; i < size; i++) {
+ slot = &state->stack[MAX_BPF_STACK + off + i];
+ slot->stype = STACK_MISC;
+ slot->reg_st.type = UNKNOWN_VALUE;
+ slot->reg_st.map_ptr = NULL;
+ }
+ }
+ return 0;
+}
+
+static int check_stack_read(struct verifier_state *state, int off, int size,
+ int value_regno)
+{
+ int i;
+ struct bpf_stack_slot *slot;
+
+ slot = &state->stack[MAX_BPF_STACK + off];
+
+ if (slot->stype == STACK_SPILL) {
+ if (size != 8) {
+ verbose("invalid size of register spill\n");
+ return -EACCES;
+ }
+ for (i = 1; i < 8; i++) {
+ if (state->stack[MAX_BPF_STACK + off + i].stype !=
+ STACK_SPILL_PART) {
+ verbose("corrupted spill memory\n");
+ return -EACCES;
+ }
+ }
+
+ if (value_regno >= 0)
+ /* restore register state from stack */
+ state->regs[value_regno] = slot->reg_st;
+ return 0;
+ } else {
+ for (i = 0; i < size; i++) {
+ if (state->stack[MAX_BPF_STACK + off + i].stype !=
+ STACK_MISC) {
+ verbose("invalid read from stack off %d+%d size %d\n",
+ off, i, size);
+ return -EACCES;
+ }
+ }
+ if (value_regno >= 0)
+ /* have read misc data from the stack */
+ mark_reg_unknown_value(state->regs, value_regno);
+ return 0;
+ }
+}
+
+/* check read/write into map element returned by bpf_map_lookup_elem() */
+static int check_map_access(struct verifier_env *env, u32 regno, int off,
+ int size)
+{
+ struct bpf_map *map = env->cur_state.regs[regno].map_ptr;
+
+ if (off < 0 || off + size > map->value_size) {
+ verbose("invalid access to map value, value_size=%d off=%d size=%d\n",
+ map->value_size, off, 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))
+ return 0;
+
+ verbose("invalid bpf_context access off=%d size=%d\n", off, size);
+ return -EACCES;
+}
+
+/* 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
+ * if t==write && value_regno==-1, some unknown value is stored into memory
+ * if t==read && value_regno==-1, don't care what we read from memory
+ */
+static int check_mem_access(struct verifier_env *env, u32 regno, int off,
+ int bpf_size, enum bpf_access_type t,
+ int value_regno)
+{
+ struct verifier_state *state = &env->cur_state;
+ int size, err = 0;
+
+ 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;
+ }
+
+ if (state->regs[regno].type == PTR_TO_MAP_VALUE) {
+ err = check_map_access(env, regno, off, size);
+ 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) {
+ err = check_ctx_access(env, off, size, t);
+ if (!err && t == BPF_READ && value_regno >= 0)
+ mark_reg_unknown_value(state->regs, value_regno);
+
+ } else if (state->regs[regno].type == FRAME_PTR) {
+ if (off >= 0 || off < -MAX_BPF_STACK) {
+ verbose("invalid stack off=%d size=%d\n", off, size);
+ return -EACCES;
+ }
+ if (t == BPF_WRITE)
+ err = check_stack_write(state, off, size, value_regno);
+ else
+ err = check_stack_read(state, off, size, value_regno);
+ } else {
+ verbose("R%d invalid mem access '%s'\n",
+ regno, reg_type_str[state->regs[regno].type]);
+ return -EACCES;
+ }
+ return err;
+}
+
+static int check_xadd(struct verifier_env *env, struct bpf_insn *insn)
+{
+ struct reg_state *regs = env->cur_state.regs;
+ int err;
+
+ if ((BPF_SIZE(insn->code) != BPF_W && BPF_SIZE(insn->code) != BPF_DW) ||
+ insn->imm != 0) {
+ verbose("BPF_XADD uses reserved fields\n");
+ return -EINVAL;
+ }
+
+ /* check src1 operand */
+ err = check_reg_arg(regs, insn->src_reg, SRC_OP);
+ if (err)
+ return err;
+
+ /* check src2 operand */
+ err = check_reg_arg(regs, insn->dst_reg, SRC_OP);
+ if (err)
+ return err;
+
+ /* check whether atomic_add can read the memory */
+ err = check_mem_access(env, insn->dst_reg, insn->off,
+ BPF_SIZE(insn->code), BPF_READ, -1);
+ if (err)
+ return err;
+
+ /* check whether atomic_add can write into the same memory */
+ return check_mem_access(env, insn->dst_reg, insn->off,
+ BPF_SIZE(insn->code), BPF_WRITE, -1);
+}
+
+/* when register 'regno' is passed into function that will read 'access_size'
+ * bytes from that pointer, make sure that it's within stack boundary
+ * and all elements of stack are initialized
+ */
+static int check_stack_boundary(struct verifier_env *env,
+ int regno, int access_size)
+{
+ struct verifier_state *state = &env->cur_state;
+ struct reg_state *regs = state->regs;
+ int off, i;
+
+ if (regs[regno].type != PTR_TO_STACK)
+ return -EACCES;
+
+ off = regs[regno].imm;
+ if (off >= 0 || off < -MAX_BPF_STACK || off + access_size > 0 ||
+ access_size <= 0) {
+ verbose("invalid stack type R%d off=%d access_size=%d\n",
+ regno, off, access_size);
+ return -EACCES;
+ }
+
+ for (i = 0; i < access_size; i++) {
+ if (state->stack[MAX_BPF_STACK + off + i].stype != STACK_MISC) {
+ verbose("invalid indirect read from stack off %d+%d size %d\n",
+ off, i, access_size);
+ return -EACCES;
+ }
+ }
+ return 0;
+}
+
+static int check_func_arg(struct verifier_env *env, u32 regno,
+ enum bpf_arg_type arg_type, struct bpf_map **mapp)
+{
+ struct reg_state *reg = env->cur_state.regs + regno;
+ enum bpf_reg_type expected_type;
+ int err = 0;
+
+ if (arg_type == ARG_ANYTHING)
+ return 0;
+
+ if (reg->type == NOT_INIT) {
+ verbose("R%d !read_ok\n", regno);
+ return -EACCES;
+ }
+
+ if (arg_type == ARG_PTR_TO_STACK || arg_type == ARG_PTR_TO_MAP_KEY ||
+ arg_type == ARG_PTR_TO_MAP_VALUE) {
+ expected_type = PTR_TO_STACK;
+ } else if (arg_type == ARG_CONST_STACK_SIZE) {
+ expected_type = CONST_IMM;
+ } else if (arg_type == ARG_CONST_MAP_PTR) {
+ expected_type = CONST_PTR_TO_MAP;
+ } else {
+ verbose("unsupported arg_type %d\n", arg_type);
+ return -EFAULT;
+ }
+
+ if (reg->type != expected_type) {
+ verbose("R%d type=%s expected=%s\n", regno,
+ reg_type_str[reg->type], reg_type_str[expected_type]);
+ return -EACCES;
+ }
+
+ if (arg_type == ARG_CONST_MAP_PTR) {
+ /* bpf_map_xxx(map_ptr) call: remember that map_ptr */
+ *mapp = 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) {
+ /* 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
+ * that kernel subsystem misconfigured verifier
+ */
+ verbose("invalid map_ptr to access map->key\n");
+ return -EACCES;
+ }
+ err = check_stack_boundary(env, regno, (*mapp)->key_size);
+
+ } 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) {
+ /* kernel subsystem misconfigured verifier */
+ verbose("invalid map_ptr to access map->value\n");
+ return -EACCES;
+ }
+ err = check_stack_boundary(env, regno, (*mapp)->value_size);
+
+ } else if (arg_type == ARG_CONST_STACK_SIZE) {
+ /* bpf_xxx(..., buf, len) call will access 'len' bytes
+ * from stack pointer 'buf'. Check it
+ * note: regno == len, regno - 1 == buf
+ */
+ if (regno == 0) {
+ /* kernel subsystem misconfigured verifier */
+ verbose("ARG_CONST_STACK_SIZE cannot be first argument\n");
+ return -EACCES;
+ }
+ err = check_stack_boundary(env, regno - 1, reg->imm);
+ }
+
+ return err;
+}
+
+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;
+ int i, err;
+
+ /* find function prototype */
+ if (func_id < 0 || func_id >= __BPF_FUNC_MAX_ID) {
+ verbose("invalid func %d\n", func_id);
+ return -EINVAL;
+ }
+
+ if (env->prog->aux->ops->get_func_proto)
+ fn = env->prog->aux->ops->get_func_proto(func_id);
+
+ if (!fn) {
+ verbose("unknown func %d\n", func_id);
+ return -EINVAL;
+ }
+
+ /* eBPF programs must be GPL compatible to use GPL-ed functions */
+ if (!env->prog->aux->is_gpl_compatible && fn->gpl_only) {
+ verbose("cannot call GPL only function from proprietary program\n");
+ return -EINVAL;
+ }
+
+ /* check args */
+ err = check_func_arg(env, BPF_REG_1, fn->arg1_type, &map);
+ if (err)
+ return err;
+ err = check_func_arg(env, BPF_REG_2, fn->arg2_type, &map);
+ if (err)
+ return err;
+ err = check_func_arg(env, BPF_REG_3, fn->arg3_type, &map);
+ if (err)
+ return err;
+ err = check_func_arg(env, BPF_REG_4, fn->arg4_type, &map);
+ if (err)
+ return err;
+ err = check_func_arg(env, BPF_REG_5, fn->arg5_type, &map);
+ if (err)
+ return err;
+
+ /* reset caller saved regs */
+ for (i = 0; i < CALLER_SAVED_REGS; i++) {
+ reg = regs + caller_saved[i];
+ reg->type = NOT_INIT;
+ reg->imm = 0;
+ }
+
+ /* update return register */
+ if (fn->ret_type == RET_INTEGER) {
+ regs[BPF_REG_0].type = UNKNOWN_VALUE;
+ } else if (fn->ret_type == RET_VOID) {
+ regs[BPF_REG_0].type = NOT_INIT;
+ } else if (fn->ret_type == RET_PTR_TO_MAP_VALUE_OR_NULL) {
+ regs[BPF_REG_0].type = PTR_TO_MAP_VALUE_OR_NULL;
+ /* remember map_ptr, so that check_map_access()
+ * can check 'value_size' boundary of memory access
+ * to map element returned from bpf_map_lookup_elem()
+ */
+ if (map == NULL) {
+ verbose("kernel subsystem misconfigured verifier\n");
+ return -EINVAL;
+ }
+ regs[BPF_REG_0].map_ptr = map;
+ } else {
+ verbose("unknown return type %d of func %d\n",
+ fn->ret_type, func_id);
+ return -EINVAL;
+ }
+ return 0;
+}
+
+/* check validity of 32-bit and 64-bit arithmetic operations */
+static int check_alu_op(struct reg_state *regs, struct bpf_insn *insn)
+{
+ u8 opcode = BPF_OP(insn->code);
+ int err;
+
+ if (opcode == BPF_END || opcode == BPF_NEG) {
+ if (opcode == BPF_NEG) {
+ if (BPF_SRC(insn->code) != 0 ||
+ insn->src_reg != BPF_REG_0 ||
+ insn->off != 0 || insn->imm != 0) {
+ verbose("BPF_NEG uses reserved fields\n");
+ return -EINVAL;
+ }
+ } else {
+ if (insn->src_reg != BPF_REG_0 || insn->off != 0 ||
+ (insn->imm != 16 && insn->imm != 32 && insn->imm != 64)) {
+ verbose("BPF_END uses reserved fields\n");
+ return -EINVAL;
+ }
+ }
+
+ /* check src operand */
+ err = check_reg_arg(regs, insn->dst_reg, SRC_OP);
+ if (err)
+ return err;
+
+ /* check dest operand */
+ err = check_reg_arg(regs, insn->dst_reg, DST_OP);
+ if (err)
+ return err;
+
+ } else if (opcode == BPF_MOV) {
+
+ if (BPF_SRC(insn->code) == BPF_X) {
+ if (insn->imm != 0 || insn->off != 0) {
+ verbose("BPF_MOV uses reserved fields\n");
+ return -EINVAL;
+ }
+
+ /* check src operand */
+ err = check_reg_arg(regs, insn->src_reg, SRC_OP);
+ if (err)
+ return err;
+ } else {
+ if (insn->src_reg != BPF_REG_0 || insn->off != 0) {
+ verbose("BPF_MOV uses reserved fields\n");
+ return -EINVAL;
+ }
+ }
+
+ /* check dest operand */
+ err = check_reg_arg(regs, insn->dst_reg, DST_OP);
+ if (err)
+ return err;
+
+ if (BPF_SRC(insn->code) == BPF_X) {
+ if (BPF_CLASS(insn->code) == BPF_ALU64) {
+ /* case: R1 = R2
+ * copy register state to dest reg
+ */
+ regs[insn->dst_reg] = regs[insn->src_reg];
+ } else {
+ regs[insn->dst_reg].type = UNKNOWN_VALUE;
+ regs[insn->dst_reg].map_ptr = NULL;
+ }
+ } else {
+ /* case: R = imm
+ * remember the value we stored into this reg
+ */
+ regs[insn->dst_reg].type = CONST_IMM;
+ regs[insn->dst_reg].imm = insn->imm;
+ }
+
+ } else if (opcode > BPF_END) {
+ verbose("invalid BPF_ALU opcode %x\n", opcode);
+ return -EINVAL;
+
+ } 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");
+ return -EINVAL;
+ }
+ /* check src1 operand */
+ err = check_reg_arg(regs, insn->src_reg, SRC_OP);
+ if (err)
+ return err;
+ } else {
+ if (insn->src_reg != BPF_REG_0 || insn->off != 0) {
+ verbose("BPF_ALU uses reserved fields\n");
+ return -EINVAL;
+ }
+ }
+
+ /* check src2 operand */
+ err = check_reg_arg(regs, insn->dst_reg, SRC_OP);
+ if (err)
+ return err;
+
+ if ((opcode == BPF_MOD || opcode == BPF_DIV) &&
+ BPF_SRC(insn->code) == BPF_K && insn->imm == 0) {
+ verbose("div by zero\n");
+ return -EINVAL;
+ }
+
+ /* 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;
+
+ /* 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;
+ }
+ }
+
+ return 0;
+}
+
+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 verifier_state *other_branch;
+ u8 opcode = BPF_OP(insn->code);
+ int err;
+
+ if (opcode > BPF_EXIT) {
+ verbose("invalid BPF_JMP opcode %x\n", opcode);
+ return -EINVAL;
+ }
+
+ if (BPF_SRC(insn->code) == BPF_X) {
+ if (insn->imm != 0) {
+ verbose("BPF_JMP uses reserved fields\n");
+ return -EINVAL;
+ }
+
+ /* check src1 operand */
+ err = check_reg_arg(regs, insn->src_reg, SRC_OP);
+ if (err)
+ return err;
+ } else {
+ if (insn->src_reg != BPF_REG_0) {
+ verbose("BPF_JMP uses reserved fields\n");
+ return -EINVAL;
+ }
+ }
+
+ /* check src2 operand */
+ err = check_reg_arg(regs, insn->dst_reg, SRC_OP);
+ if (err)
+ return err;
+
+ /* 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) {
+ if (opcode == BPF_JEQ) {
+ /* if (imm == imm) goto pc+off;
+ * only follow the goto, ignore fall-through
+ */
+ *insn_idx += insn->off;
+ return 0;
+ } else {
+ /* if (imm != imm) goto pc+off;
+ * only follow fall-through branch, since
+ * that's where the program will go
+ */
+ return 0;
+ }
+ }
+
+ other_branch = push_stack(env, *insn_idx + insn->off + 1, *insn_idx);
+ if (!other_branch)
+ return -EFAULT;
+
+ /* 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) {
+ 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;
+ } 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;
+ }
+ } 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);
+ return 0;
+}
+
+/* return the map pointer stored inside BPF_LD_IMM64 instruction */
+static struct bpf_map *ld_imm64_to_map_ptr(struct bpf_insn *insn)
+{
+ u64 imm64 = ((u64) (u32) insn[0].imm) | ((u64) (u32) insn[1].imm) << 32;
+
+ return (struct bpf_map *) (unsigned long) imm64;
+}
+
+/* verify BPF_LD_IMM64 instruction */
+static int check_ld_imm(struct verifier_env *env, struct bpf_insn *insn)
+{
+ struct reg_state *regs = env->cur_state.regs;
+ int err;
+
+ if (BPF_SIZE(insn->code) != BPF_DW) {
+ verbose("invalid BPF_LD_IMM insn\n");
+ return -EINVAL;
+ }
+ if (insn->off != 0) {
+ verbose("BPF_LD_IMM64 uses reserved fields\n");
+ return -EINVAL;
+ }
+
+ err = check_reg_arg(regs, insn->dst_reg, DST_OP);
+ if (err)
+ return err;
+
+ if (insn->src_reg == 0)
+ /* generic move 64-bit immediate into a register */
+ return 0;
+
+ /* replace_map_fd_with_map_ptr() should have caught bad ld_imm64 */
+ BUG_ON(insn->src_reg != BPF_PSEUDO_MAP_FD);
+
+ regs[insn->dst_reg].type = CONST_PTR_TO_MAP;
+ regs[insn->dst_reg].map_ptr = ld_imm64_to_map_ptr(insn);
+ return 0;
+}
+
+/* non-recursive DFS pseudo code
+ * 1 procedure DFS-iterative(G,v):
+ * 2 label v as discovered
+ * 3 let S be a stack
+ * 4 S.push(v)
+ * 5 while S is not empty
+ * 6 t <- S.pop()
+ * 7 if t is what we're looking for:
+ * 8 return t
+ * 9 for all edges e in G.adjacentEdges(t) do
+ * 10 if edge e is already labelled
+ * 11 continue with the next edge
+ * 12 w <- G.adjacentVertex(t,e)
+ * 13 if vertex w is not discovered and not explored
+ * 14 label e as tree-edge
+ * 15 label w as discovered
+ * 16 S.push(w)
+ * 17 continue at 5
+ * 18 else if vertex w is discovered
+ * 19 label e as back-edge
+ * 20 else
+ * 21 // vertex w is explored
+ * 22 label e as forward- or cross-edge
+ * 23 label t as explored
+ * 24 S.pop()
+ *
+ * convention:
+ * 0x10 - discovered
+ * 0x11 - discovered and fall-through edge labelled
+ * 0x12 - discovered and fall-through and branch edges labelled
+ * 0x20 - explored
+ */
+
+enum {
+ DISCOVERED = 0x10,
+ EXPLORED = 0x20,
+ FALLTHROUGH = 1,
+ BRANCH = 2,
+};
+
+#define STATE_LIST_MARK ((struct verifier_state_list *) -1L)
+
+static int *insn_stack; /* stack of insns to process */
+static int cur_stack; /* current stack index */
+static int *insn_state;
+
+/* t, w, e - match pseudo-code above:
+ * t - index of current instruction
+ * w - next instruction
+ * e - edge
+ */
+static int push_insn(int t, int w, int e, struct verifier_env *env)
+{
+ if (e == FALLTHROUGH && insn_state[t] >= (DISCOVERED | FALLTHROUGH))
+ return 0;
+
+ if (e == BRANCH && insn_state[t] >= (DISCOVERED | BRANCH))
+ return 0;
+
+ if (w < 0 || w >= env->prog->len) {
+ verbose("jump out of range from insn %d to %d\n", t, w);
+ return -EINVAL;
+ }
+
+ if (e == BRANCH)
+ /* mark branch target for state pruning */
+ env->explored_states[w] = STATE_LIST_MARK;
+
+ if (insn_state[w] == 0) {
+ /* tree-edge */
+ insn_state[t] = DISCOVERED | e;
+ insn_state[w] = DISCOVERED;
+ if (cur_stack >= env->prog->len)
+ return -E2BIG;
+ insn_stack[cur_stack++] = w;
+ return 1;
+ } else if ((insn_state[w] & 0xF0) == DISCOVERED) {
+ verbose("back-edge from insn %d to %d\n", t, w);
+ return -EINVAL;
+ } else if (insn_state[w] == EXPLORED) {
+ /* forward- or cross-edge */
+ insn_state[t] = DISCOVERED | e;
+ } else {
+ verbose("insn state internal bug\n");
+ return -EFAULT;
+ }
+ return 0;
+}
+
+/* non-recursive depth-first-search to detect loops in BPF program
+ * loop == back-edge in directed graph
+ */
+static int check_cfg(struct verifier_env *env)
+{
+ struct bpf_insn *insns = env->prog->insnsi;
+ int insn_cnt = env->prog->len;
+ int ret = 0;
+ int i, t;
+
+ insn_state = kcalloc(insn_cnt, sizeof(int), GFP_KERNEL);
+ if (!insn_state)
+ return -ENOMEM;
+
+ insn_stack = kcalloc(insn_cnt, sizeof(int), GFP_KERNEL);
+ if (!insn_stack) {
+ kfree(insn_state);
+ return -ENOMEM;
+ }
+
+ insn_state[0] = DISCOVERED; /* mark 1st insn as discovered */
+ insn_stack[0] = 0; /* 0 is the first instruction */
+ cur_stack = 1;
+
+peek_stack:
+ if (cur_stack == 0)
+ goto check_state;
+ t = insn_stack[cur_stack - 1];
+
+ if (BPF_CLASS(insns[t].code) == BPF_JMP) {
+ u8 opcode = BPF_OP(insns[t].code);
+
+ if (opcode == BPF_EXIT) {
+ goto mark_explored;
+ } else if (opcode == BPF_CALL) {
+ ret = push_insn(t, t + 1, FALLTHROUGH, env);
+ if (ret == 1)
+ goto peek_stack;
+ else if (ret < 0)
+ goto err_free;
+ } else if (opcode == BPF_JA) {
+ if (BPF_SRC(insns[t].code) != BPF_K) {
+ ret = -EINVAL;
+ goto err_free;
+ }
+ /* unconditional jump with single edge */
+ ret = push_insn(t, t + insns[t].off + 1,
+ FALLTHROUGH, env);
+ if (ret == 1)
+ goto peek_stack;
+ else if (ret < 0)
+ goto err_free;
+ /* tell verifier to check for equivalent states
+ * after every call and jump
+ */
+ env->explored_states[t + 1] = STATE_LIST_MARK;
+ } else {
+ /* conditional jump with two edges */
+ ret = push_insn(t, t + 1, FALLTHROUGH, env);
+ if (ret == 1)
+ goto peek_stack;
+ else if (ret < 0)
+ goto err_free;
+
+ ret = push_insn(t, t + insns[t].off + 1, BRANCH, env);
+ if (ret == 1)
+ goto peek_stack;
+ else if (ret < 0)
+ goto err_free;
+ }
+ } else {
+ /* all other non-branch instructions with single
+ * fall-through edge
+ */
+ ret = push_insn(t, t + 1, FALLTHROUGH, env);
+ if (ret == 1)
+ goto peek_stack;
+ else if (ret < 0)
+ goto err_free;
+ }
+
+mark_explored:
+ insn_state[t] = EXPLORED;
+ if (cur_stack-- <= 0) {
+ verbose("pop stack internal bug\n");
+ ret = -EFAULT;
+ goto err_free;
+ }
+ goto peek_stack;
+
+check_state:
+ for (i = 0; i < insn_cnt; i++) {
+ if (insn_state[i] != EXPLORED) {
+ verbose("unreachable insn %d\n", i);
+ ret = -EINVAL;
+ goto err_free;
+ }
+ }
+ ret = 0; /* cfg looks good */
+
+err_free:
+ kfree(insn_state);
+ kfree(insn_stack);
+ return ret;
+}
+
+/* compare two verifier states
+ *
+ * all states stored in state_list are known to be valid, since
+ * verifier reached 'bpf_exit' instruction through them
+ *
+ * this function is called when verifier exploring different branches of
+ * execution popped from the state stack. If it sees an old state that has
+ * more strict register state and more strict stack state then this execution
+ * branch doesn't need to be explored further, since verifier already
+ * concluded that more strict state leads to valid finish.
+ *
+ * Therefore two states are equivalent if register state is more conservative
+ * and explored stack state is more conservative than the current one.
+ * Example:
+ * explored current
+ * (slot1=INV slot2=MISC) == (slot1=MISC slot2=MISC)
+ * (slot1=MISC slot2=MISC) != (slot1=INV slot2=MISC)
+ *
+ * In other words if current stack state (one being explored) has more
+ * valid slots than old one that already passed validation, it means
+ * the verifier can stop exploring and conclude that current state is valid too
+ *
+ * Similarly with registers. If explored state has register type as invalid
+ * whereas register type in current state is meaningful, it means that
+ * the current state will reach 'bpf_exit' instruction safely
+ */
+static bool states_equal(struct verifier_state *old, struct verifier_state *cur)
+{
+ 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)
+ continue;
+ return false;
+ }
+ }
+
+ for (i = 0; i < MAX_BPF_STACK; i++) {
+ if (memcmp(&old->stack[i], &cur->stack[i],
+ sizeof(old->stack[0])) != 0) {
+ if (old->stack[i].stype == STACK_INVALID)
+ continue;
+ return false;
+ }
+ }
+ return true;
+}
+
+static int is_state_visited(struct verifier_env *env, int insn_idx)
+{
+ struct verifier_state_list *new_sl;
+ struct verifier_state_list *sl;
+
+ sl = env->explored_states[insn_idx];
+ if (!sl)
+ /* this 'insn_idx' instruction wasn't marked, so we will not
+ * be doing state search here
+ */
+ return 0;
+
+ while (sl != STATE_LIST_MARK) {
+ if (states_equal(&sl->state, &env->cur_state))
+ /* reached equivalent register/stack state,
+ * prune the search
+ */
+ return 1;
+ sl = sl->next;
+ }
+
+ /* there were no equivalent states, remember current one.
+ * technically the current state is not proven to be safe yet,
+ * but it will either reach bpf_exit (which means it's safe) or
+ * it will be rejected. Since there are no loops, we won't be
+ * seeing this 'insn_idx' instruction again on the way to bpf_exit
+ */
+ new_sl = kmalloc(sizeof(struct verifier_state_list), GFP_USER);
+ if (!new_sl)
+ return -ENOMEM;
+
+ /* add new state to the head of linked list */
+ memcpy(&new_sl->state, &env->cur_state, sizeof(env->cur_state));
+ new_sl->next = env->explored_states[insn_idx];
+ env->explored_states[insn_idx] = new_sl;
+ return 0;
+}
+
+static int do_check(struct verifier_env *env)
+{
+ struct verifier_state *state = &env->cur_state;
+ struct bpf_insn *insns = env->prog->insnsi;
+ struct reg_state *regs = state->regs;
+ int insn_cnt = env->prog->len;
+ int insn_idx, prev_insn_idx = 0;
+ int insn_processed = 0;
+ bool do_print_state = false;
+
+ init_reg_state(regs);
+ insn_idx = 0;
+ for (;;) {
+ struct bpf_insn *insn;
+ u8 class;
+ int err;
+
+ if (insn_idx >= insn_cnt) {
+ verbose("invalid insn idx %d insn_cnt %d\n",
+ insn_idx, insn_cnt);
+ return -EFAULT;
+ }
+
+ insn = &insns[insn_idx];
+ class = BPF_CLASS(insn->code);
+
+ if (++insn_processed > 32768) {
+ verbose("BPF program is too large. Proccessed %d insn\n",
+ insn_processed);
+ return -E2BIG;
+ }
+
+ err = is_state_visited(env, insn_idx);
+ if (err < 0)
+ return err;
+ if (err == 1) {
+ /* found equivalent state, can prune the search */
+ if (log_level) {
+ if (do_print_state)
+ verbose("\nfrom %d to %d: safe\n",
+ prev_insn_idx, insn_idx);
+ else
+ verbose("%d: safe\n", insn_idx);
+ }
+ goto process_bpf_exit;
+ }
+
+ if (log_level && do_print_state) {
+ verbose("\nfrom %d to %d:", prev_insn_idx, insn_idx);
+ print_verifier_state(env);
+ do_print_state = false;
+ }
+
+ if (log_level) {
+ verbose("%d: ", insn_idx);
+ print_bpf_insn(insn);
+ }
+
+ if (class == BPF_ALU || class == BPF_ALU64) {
+ err = check_alu_op(regs, insn);
+ if (err)
+ return err;
+
+ } else if (class == BPF_LDX) {
+ if (BPF_MODE(insn->code) != BPF_MEM ||
+ insn->imm != 0) {
+ verbose("BPF_LDX uses reserved fields\n");
+ return -EINVAL;
+ }
+ /* check src operand */
+ err = check_reg_arg(regs, insn->src_reg, SRC_OP);
+ if (err)
+ return err;
+
+ err = check_reg_arg(regs, insn->dst_reg, DST_OP_NO_MARK);
+ if (err)
+ return err;
+
+ /* check that memory (src_reg + off) is readable,
+ * the state of dst_reg will be updated by this func
+ */
+ err = check_mem_access(env, insn->src_reg, insn->off,
+ BPF_SIZE(insn->code), BPF_READ,
+ insn->dst_reg);
+ if (err)
+ return err;
+
+ } else if (class == BPF_STX) {
+ if (BPF_MODE(insn->code) == BPF_XADD) {
+ err = check_xadd(env, insn);
+ if (err)
+ return err;
+ insn_idx++;
+ continue;
+ }
+
+ if (BPF_MODE(insn->code) != BPF_MEM ||
+ insn->imm != 0) {
+ verbose("BPF_STX uses reserved fields\n");
+ return -EINVAL;
+ }
+ /* check src1 operand */
+ err = check_reg_arg(regs, insn->src_reg, SRC_OP);
+ if (err)
+ return err;
+ /* check src2 operand */
+ err = check_reg_arg(regs, insn->dst_reg, SRC_OP);
+ if (err)
+ return err;
+
+ /* check that memory (dst_reg + off) is writeable */
+ err = check_mem_access(env, insn->dst_reg, insn->off,
+ BPF_SIZE(insn->code), BPF_WRITE,
+ insn->src_reg);
+ if (err)
+ return err;
+
+ } else if (class == BPF_ST) {
+ if (BPF_MODE(insn->code) != BPF_MEM ||
+ insn->src_reg != BPF_REG_0) {
+ verbose("BPF_ST uses reserved fields\n");
+ return -EINVAL;
+ }
+ /* check src operand */
+ err = check_reg_arg(regs, insn->dst_reg, SRC_OP);
+ if (err)
+ return err;
+
+ /* check that memory (dst_reg + off) is writeable */
+ err = check_mem_access(env, insn->dst_reg, insn->off,
+ BPF_SIZE(insn->code), BPF_WRITE,
+ -1);
+ if (err)
+ return err;
+
+ } else if (class == BPF_JMP) {
+ u8 opcode = BPF_OP(insn->code);
+
+ if (opcode == BPF_CALL) {
+ if (BPF_SRC(insn->code) != BPF_K ||
+ insn->off != 0 ||
+ insn->src_reg != BPF_REG_0 ||
+ insn->dst_reg != BPF_REG_0) {
+ verbose("BPF_CALL uses reserved fields\n");
+ return -EINVAL;
+ }
+
+ err = check_call(env, insn->imm);
+ if (err)
+ return err;
+
+ } else if (opcode == BPF_JA) {
+ if (BPF_SRC(insn->code) != BPF_K ||
+ insn->imm != 0 ||
+ insn->src_reg != BPF_REG_0 ||
+ insn->dst_reg != BPF_REG_0) {
+ verbose("BPF_JA uses reserved fields\n");
+ return -EINVAL;
+ }
+
+ insn_idx += insn->off + 1;
+ continue;
+
+ } else if (opcode == BPF_EXIT) {
+ if (BPF_SRC(insn->code) != BPF_K ||
+ insn->imm != 0 ||
+ insn->src_reg != BPF_REG_0 ||
+ insn->dst_reg != BPF_REG_0) {
+ verbose("BPF_EXIT uses reserved fields\n");
+ return -EINVAL;
+ }
+
+ /* eBPF calling convetion is such that R0 is used
+ * to return the value from eBPF program.
+ * Make sure that it's readable at this time
+ * of bpf_exit, which means that program wrote
+ * something into it earlier
+ */
+ err = check_reg_arg(regs, BPF_REG_0, SRC_OP);
+ if (err)
+ return err;
+
+process_bpf_exit:
+ insn_idx = pop_stack(env, &prev_insn_idx);
+ if (insn_idx < 0) {
+ break;
+ } else {
+ do_print_state = true;
+ continue;
+ }
+ } else {
+ err = check_cond_jmp_op(env, insn, &insn_idx);
+ if (err)
+ return err;
+ }
+ } else if (class == BPF_LD) {
+ u8 mode = BPF_MODE(insn->code);
+
+ if (mode == BPF_ABS || mode == BPF_IND) {
+ verbose("LD_ABS is not supported yet\n");
+ return -EINVAL;
+ } else if (mode == BPF_IMM) {
+ err = check_ld_imm(env, insn);
+ if (err)
+ return err;
+
+ insn_idx++;
+ } else {
+ verbose("invalid BPF_LD mode\n");
+ return -EINVAL;
+ }
+ } else {
+ verbose("unknown insn class %d\n", class);
+ return -EINVAL;
+ }
+
+ insn_idx++;
+ }
+
+ return 0;
+}
+
+/* look for pseudo eBPF instructions that access map FDs and
+ * replace them with actual map pointers
+ */
+static int replace_map_fd_with_map_ptr(struct verifier_env *env)
+{
+ struct bpf_insn *insn = env->prog->insnsi;
+ int insn_cnt = env->prog->len;
+ int i, j;
+
+ for (i = 0; i < insn_cnt; i++, insn++) {
+ if (insn[0].code == (BPF_LD | BPF_IMM | BPF_DW)) {
+ struct bpf_map *map;
+ struct fd f;
+
+ if (i == insn_cnt - 1 || insn[1].code != 0 ||
+ insn[1].dst_reg != 0 || insn[1].src_reg != 0 ||
+ insn[1].off != 0) {
+ verbose("invalid bpf_ld_imm64 insn\n");
+ return -EINVAL;
+ }
+
+ if (insn->src_reg == 0)
+ /* valid generic load 64-bit imm */
+ goto next_insn;
+
+ if (insn->src_reg != BPF_PSEUDO_MAP_FD) {
+ verbose("unrecognized bpf_ld_imm64 insn\n");
+ return -EINVAL;
+ }
+
+ f = fdget(insn->imm);
+
+ map = bpf_map_get(f);
+ if (IS_ERR(map)) {
+ verbose("fd %d is not pointing to valid bpf_map\n",
+ insn->imm);
+ fdput(f);
+ return PTR_ERR(map);
+ }
+
+ /* store map pointer inside BPF_LD_IMM64 instruction */
+ insn[0].imm = (u32) (unsigned long) map;
+ insn[1].imm = ((u64) (unsigned long) map) >> 32;
+
+ /* check whether we recorded this map already */
+ for (j = 0; j < env->used_map_cnt; j++)
+ if (env->used_maps[j] == map) {
+ fdput(f);
+ goto next_insn;
+ }
+
+ if (env->used_map_cnt >= MAX_USED_MAPS) {
+ fdput(f);
+ 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()
+ */
+ atomic_inc(&map->refcnt);
+
+ fdput(f);
+next_insn:
+ insn++;
+ i++;
+ }
+ }
+
+ /* now all pseudo BPF_LD_IMM64 instructions load valid
+ * 'struct bpf_map *' into a register instead of user map_fd.
+ * These pointers will be used later by verifier to validate map access.
+ */
+ return 0;
+}
+
+/* drop refcnt of maps used by the rejected program */
+static void release_maps(struct verifier_env *env)
+{
+ int i;
+
+ for (i = 0; i < env->used_map_cnt; i++)
+ bpf_map_put(env->used_maps[i]);
+}
+
+/* convert pseudo BPF_LD_IMM64 into generic BPF_LD_IMM64 */
+static void convert_pseudo_ld_imm64(struct verifier_env *env)
+{
+ struct bpf_insn *insn = env->prog->insnsi;
+ int insn_cnt = env->prog->len;
+ int i;
+
+ for (i = 0; i < insn_cnt; i++, insn++)
+ if (insn->code == (BPF_LD | BPF_IMM | BPF_DW))
+ insn->src_reg = 0;
+}
+
+static void free_states(struct verifier_env *env)
+{
+ struct verifier_state_list *sl, *sln;
+ int i;
+
+ if (!env->explored_states)
+ return;
+
+ for (i = 0; i < env->prog->len; i++) {
+ sl = env->explored_states[i];
+
+ if (sl)
+ while (sl != STATE_LIST_MARK) {
+ sln = sl->next;
+ kfree(sl);
+ sl = sln;
+ }
+ }
+
+ kfree(env->explored_states);
+}
+
+int bpf_check(struct bpf_prog *prog, union bpf_attr *attr)
+{
+ char __user *log_ubuf = NULL;
+ struct verifier_env *env;
+ int ret = -EINVAL;
+
+ if (prog->len <= 0 || prog->len > BPF_MAXINSNS)
+ return -E2BIG;
+
+ /* 'struct verifier_env' can be global, but since it's not small,
+ * allocate/free it every time bpf_check() is called
+ */
+ env = kzalloc(sizeof(struct verifier_env), GFP_KERNEL);
+ if (!env)
+ return -ENOMEM;
+
+ env->prog = prog;
+
+ /* grab the mutex to protect few globals used by verifier */
+ mutex_lock(&bpf_verifier_lock);
+
+ if (attr->log_level || attr->log_buf || attr->log_size) {
+ /* user requested verbose verifier output
+ * and supplied buffer to store the verification trace
+ */
+ log_level = attr->log_level;
+ log_ubuf = (char __user *) (unsigned long) attr->log_buf;
+ log_size = attr->log_size;
+ log_len = 0;
+
+ ret = -EINVAL;
+ /* log_* values have to be sane */
+ if (log_size < 128 || log_size > UINT_MAX >> 8 ||
+ log_level == 0 || log_ubuf == NULL)
+ goto free_env;
+
+ ret = -ENOMEM;
+ log_buf = vmalloc(log_size);
+ if (!log_buf)
+ goto free_env;
+ } else {
+ log_level = 0;
+ }
+
+ ret = replace_map_fd_with_map_ptr(env);
+ if (ret < 0)
+ goto skip_full_check;
+
+ env->explored_states = kcalloc(prog->len,
+ sizeof(struct verifier_state_list *),
+ GFP_USER);
+ ret = -ENOMEM;
+ if (!env->explored_states)
+ goto skip_full_check;
+
+ ret = check_cfg(env);
+ if (ret < 0)
+ goto skip_full_check;
+
+ ret = do_check(env);
+
+skip_full_check:
+ while (pop_stack(env, NULL) >= 0);
+ free_states(env);
+
+ if (log_level && log_len >= log_size - 1) {
+ BUG_ON(log_len >= log_size);
+ /* verifier log exceeded user supplied buffer */
+ ret = -ENOSPC;
+ /* fall through to return what was recorded */
+ }
+
+ /* copy verifier log back to user space including trailing zero */
+ if (log_level && copy_to_user(log_ubuf, log_buf, log_len + 1) != 0) {
+ ret = -EFAULT;
+ goto free_log_buf;
+ }
+
+ if (ret == 0 && env->used_map_cnt) {
+ /* if program passed verifier, update used_maps in bpf_prog_info */
+ prog->aux->used_maps = kmalloc_array(env->used_map_cnt,
+ sizeof(env->used_maps[0]),
+ GFP_KERNEL);
+
+ if (!prog->aux->used_maps) {
+ ret = -ENOMEM;
+ goto free_log_buf;
+ }
+
+ memcpy(prog->aux->used_maps, env->used_maps,
+ sizeof(env->used_maps[0]) * env->used_map_cnt);
+ prog->aux->used_map_cnt = env->used_map_cnt;
+
+ /* program is valid. Convert pseudo bpf_ld_imm64 into generic
+ * bpf_ld_imm64 instructions
+ */
+ convert_pseudo_ld_imm64(env);
+ }
+
+free_log_buf:
+ if (log_level)
+ vfree(log_buf);
+free_env:
+ if (!prog->aux->used_maps)
+ /* if we didn't copy map pointers into bpf_prog_info, release
+ * them now. Otherwise free_bpf_prog_info() will release them.
+ */
+ release_maps(env);
+ kfree(env);
+ mutex_unlock(&bpf_verifier_lock);
+ return ret;
+}
diff --git a/kernel/cgroup.c b/kernel/cgroup.c
index 7dc8788cfd52..136eceadeed1 100644
--- a/kernel/cgroup.c
+++ b/kernel/cgroup.c
@@ -185,7 +185,6 @@ static int need_forkexit_callback __read_mostly;
static struct cftype cgroup_dfl_base_files[];
static struct cftype cgroup_legacy_base_files[];
-static void cgroup_put(struct cgroup *cgrp);
static int rebind_subsystems(struct cgroup_root *dst_root,
unsigned int ss_mask);
static int cgroup_destroy_locked(struct cgroup *cgrp);
@@ -195,7 +194,6 @@ static void css_release(struct percpu_ref *ref);
static void kill_css(struct cgroup_subsys_state *css);
static int cgroup_addrm_files(struct cgroup *cgrp, struct cftype cfts[],
bool is_add);
-static void cgroup_pidlist_destroy_all(struct cgroup *cgrp);
/* IDR wrappers which synchronize using cgroup_idr_lock */
static int cgroup_idr_alloc(struct idr *idr, void *ptr, int start, int end,
@@ -331,14 +329,6 @@ bool cgroup_is_descendant(struct cgroup *cgrp, struct cgroup *ancestor)
return false;
}
-static int cgroup_is_releasable(const struct cgroup *cgrp)
-{
- const int bits =
- (1 << CGRP_RELEASABLE) |
- (1 << CGRP_NOTIFY_ON_RELEASE);
- return (cgrp->flags & bits) == bits;
-}
-
static int notify_on_release(const struct cgroup *cgrp)
{
return test_bit(CGRP_NOTIFY_ON_RELEASE, &cgrp->flags);
@@ -394,12 +384,7 @@ static int notify_on_release(const struct cgroup *cgrp)
; \
else
-/* the list of cgroups eligible for automatic release. Protected by
- * release_list_lock */
-static LIST_HEAD(release_list);
-static DEFINE_RAW_SPINLOCK(release_list_lock);
static void cgroup_release_agent(struct work_struct *work);
-static DECLARE_WORK(release_agent_work, cgroup_release_agent);
static void check_for_release(struct cgroup *cgrp);
/*
@@ -498,7 +483,7 @@ static unsigned long css_set_hash(struct cgroup_subsys_state *css[])
return key;
}
-static void put_css_set_locked(struct css_set *cset, bool taskexit)
+static void put_css_set_locked(struct css_set *cset)
{
struct cgrp_cset_link *link, *tmp_link;
struct cgroup_subsys *ss;
@@ -524,11 +509,7 @@ static void put_css_set_locked(struct css_set *cset, bool taskexit)
/* @cgrp can't go away while we're holding css_set_rwsem */
if (list_empty(&cgrp->cset_links)) {
cgroup_update_populated(cgrp, false);
- if (notify_on_release(cgrp)) {
- if (taskexit)
- set_bit(CGRP_RELEASABLE, &cgrp->flags);
- check_for_release(cgrp);
- }
+ check_for_release(cgrp);
}
kfree(link);
@@ -537,7 +518,7 @@ static void put_css_set_locked(struct css_set *cset, bool taskexit)
kfree_rcu(cset, rcu_head);
}
-static void put_css_set(struct css_set *cset, bool taskexit)
+static void put_css_set(struct css_set *cset)
{
/*
* Ensure that the refcount doesn't hit zero while any readers
@@ -548,7 +529,7 @@ static void put_css_set(struct css_set *cset, bool taskexit)
return;
down_write(&css_set_rwsem);
- put_css_set_locked(cset, taskexit);
+ put_css_set_locked(cset);
up_write(&css_set_rwsem);
}
@@ -969,14 +950,6 @@ static struct cgroup *task_cgroup_from_root(struct task_struct *task,
* knows that the cgroup won't be removed, as cgroup_rmdir()
* needs that mutex.
*
- * The fork and exit callbacks cgroup_fork() and cgroup_exit(), don't
- * (usually) take cgroup_mutex. These are the two most performance
- * critical pieces of code here. The exception occurs on cgroup_exit(),
- * when a task in a notify_on_release cgroup exits. Then cgroup_mutex
- * is taken, and if the cgroup count is zero, a usermode call made
- * to the release agent with the name of the cgroup (path relative to
- * the root of cgroup file system) as the argument.
- *
* A cgroup can only be deleted if both its 'count' of using tasks
* is zero, and its list of 'children' cgroups is empty. Since all
* tasks in the system use _some_ cgroup, and since there is always at
@@ -1035,6 +1008,11 @@ static void cgroup_get(struct cgroup *cgrp)
css_get(&cgrp->self);
}
+static bool cgroup_tryget(struct cgroup *cgrp)
+{
+ return css_tryget(&cgrp->self);
+}
+
static void cgroup_put(struct cgroup *cgrp)
{
css_put(&cgrp->self);
@@ -1147,7 +1125,8 @@ static struct cgroup *cgroup_kn_lock_live(struct kernfs_node *kn)
* protection against removal. Ensure @cgrp stays accessible and
* break the active_ref protection.
*/
- cgroup_get(cgrp);
+ if (!cgroup_tryget(cgrp))
+ return NULL;
kernfs_break_active_protection(kn);
mutex_lock(&cgroup_mutex);
@@ -1581,7 +1560,6 @@ static void init_cgroup_housekeeping(struct cgroup *cgrp)
INIT_LIST_HEAD(&cgrp->self.sibling);
INIT_LIST_HEAD(&cgrp->self.children);
INIT_LIST_HEAD(&cgrp->cset_links);
- INIT_LIST_HEAD(&cgrp->release_list);
INIT_LIST_HEAD(&cgrp->pidlists);
mutex_init(&cgrp->pidlist_mutex);
cgrp->self.cgroup = cgrp;
@@ -1591,6 +1569,7 @@ static void init_cgroup_housekeeping(struct cgroup *cgrp)
INIT_LIST_HEAD(&cgrp->e_csets[ssid]);
init_waitqueue_head(&cgrp->offline_waitq);
+ INIT_WORK(&cgrp->release_agent_work, cgroup_release_agent);
}
static void init_cgroup_root(struct cgroup_root *root,
@@ -1628,7 +1607,8 @@ static int cgroup_setup_root(struct cgroup_root *root, unsigned int ss_mask)
goto out;
root_cgrp->id = ret;
- ret = percpu_ref_init(&root_cgrp->self.refcnt, css_release);
+ ret = percpu_ref_init(&root_cgrp->self.refcnt, css_release, 0,
+ GFP_KERNEL);
if (ret)
goto out;
@@ -2046,8 +2026,7 @@ static void cgroup_task_migrate(struct cgroup *old_cgrp,
* task. As trading it for new_cset is protected by cgroup_mutex,
* we're safe to drop it here; it will be freed under RCU.
*/
- set_bit(CGRP_RELEASABLE, &old_cgrp->flags);
- put_css_set_locked(old_cset, false);
+ put_css_set_locked(old_cset);
}
/**
@@ -2068,7 +2047,7 @@ static void cgroup_migrate_finish(struct list_head *preloaded_csets)
cset->mg_src_cgrp = NULL;
cset->mg_dst_cset = NULL;
list_del_init(&cset->mg_preload_node);
- put_css_set_locked(cset, false);
+ put_css_set_locked(cset);
}
up_write(&css_set_rwsem);
}
@@ -2162,8 +2141,8 @@ static int cgroup_migrate_prepare_dst(struct cgroup *dst_cgrp,
if (src_cset == dst_cset) {
src_cset->mg_src_cgrp = NULL;
list_del_init(&src_cset->mg_preload_node);
- put_css_set(src_cset, false);
- put_css_set(dst_cset, false);
+ put_css_set(src_cset);
+ put_css_set(dst_cset);
continue;
}
@@ -2172,7 +2151,7 @@ static int cgroup_migrate_prepare_dst(struct cgroup *dst_cgrp,
if (list_empty(&dst_cset->mg_preload_node))
list_add(&dst_cset->mg_preload_node, &csets);
else
- put_css_set(dst_cset, false);
+ put_css_set(dst_cset);
}
list_splice_tail(&csets, preloaded_csets);
@@ -3271,8 +3250,17 @@ int cgroup_add_legacy_cftypes(struct cgroup_subsys *ss, struct cftype *cfts)
{
struct cftype *cft;
- for (cft = cfts; cft && cft->name[0] != '\0'; cft++)
- cft->flags |= __CFTYPE_NOT_ON_DFL;
+ /*
+ * If legacy_flies_on_dfl, we want to show the legacy files on the
+ * dfl hierarchy but iff the target subsystem hasn't been updated
+ * for the dfl hierarchy yet.
+ */
+ if (!cgroup_legacy_files_on_dfl ||
+ ss->dfl_cftypes != ss->legacy_cftypes) {
+ for (cft = cfts; cft && cft->name[0] != '\0'; cft++)
+ cft->flags |= __CFTYPE_NOT_ON_DFL;
+ }
+
return cgroup_add_cftypes(ss, cfts);
}
@@ -3970,7 +3958,6 @@ static int pidlist_array_load(struct cgroup *cgrp, enum cgroup_filetype type,
l = cgroup_pidlist_find_create(cgrp, type);
if (!l) {
- mutex_unlock(&cgrp->pidlist_mutex);
pidlist_free(array);
return -ENOMEM;
}
@@ -4159,7 +4146,6 @@ static u64 cgroup_read_notify_on_release(struct cgroup_subsys_state *css,
static int cgroup_write_notify_on_release(struct cgroup_subsys_state *css,
struct cftype *cft, u64 val)
{
- clear_bit(CGRP_RELEASABLE, &css->cgroup->flags);
if (val)
set_bit(CGRP_NOTIFY_ON_RELEASE, &css->cgroup->flags);
else
@@ -4337,6 +4323,7 @@ static void css_free_work_fn(struct work_struct *work)
/* cgroup free path */
atomic_dec(&cgrp->root->nr_cgrps);
cgroup_pidlist_destroy_all(cgrp);
+ cancel_work_sync(&cgrp->release_agent_work);
if (cgroup_parent(cgrp)) {
/*
@@ -4387,6 +4374,15 @@ static void css_release_work_fn(struct work_struct *work)
/* cgroup release path */
cgroup_idr_remove(&cgrp->root->cgroup_idr, cgrp->id);
cgrp->id = -1;
+
+ /*
+ * There are two control paths which try to determine
+ * cgroup from dentry without going through kernfs -
+ * cgroupstats_build() and css_tryget_online_from_dir().
+ * Those are supported by RCU protecting clearing of
+ * cgrp->kn->priv backpointer.
+ */
+ RCU_INIT_POINTER(*(void __rcu __force **)&cgrp->kn->priv, NULL);
}
mutex_unlock(&cgroup_mutex);
@@ -4487,7 +4483,7 @@ static int create_css(struct cgroup *cgrp, struct cgroup_subsys *ss,
init_and_link_css(css, ss, cgrp);
- err = percpu_ref_init(&css->refcnt, css_release);
+ err = percpu_ref_init(&css->refcnt, css_release, 0, GFP_KERNEL);
if (err)
goto err_free_css;
@@ -4543,6 +4539,11 @@ static int cgroup_mkdir(struct kernfs_node *parent_kn, const char *name,
struct cftype *base_files;
int ssid, ret;
+ /* Do not accept '\n' to prevent making /proc/<pid>/cgroup unparsable.
+ */
+ if (strchr(name, '\n'))
+ return -EINVAL;
+
parent = cgroup_kn_lock_live(parent_kn);
if (!parent)
return -ENODEV;
@@ -4555,7 +4556,7 @@ static int cgroup_mkdir(struct kernfs_node *parent_kn, const char *name,
goto out_unlock;
}
- ret = percpu_ref_init(&cgrp->self.refcnt, css_release);
+ ret = percpu_ref_init(&cgrp->self.refcnt, css_release, 0, GFP_KERNEL);
if (ret)
goto out_free_cgrp;
@@ -4785,19 +4786,12 @@ static int cgroup_destroy_locked(struct cgroup *cgrp)
for_each_css(css, ssid, cgrp)
kill_css(css);
- /* CSS_ONLINE is clear, remove from ->release_list for the last time */
- raw_spin_lock(&release_list_lock);
- if (!list_empty(&cgrp->release_list))
- list_del_init(&cgrp->release_list);
- raw_spin_unlock(&release_list_lock);
-
/*
* Remove @cgrp directory along with the base files. @cgrp has an
* extra ref on its kn.
*/
kernfs_remove(cgrp->kn);
- set_bit(CGRP_RELEASABLE, &cgroup_parent(cgrp)->flags);
check_for_release(cgroup_parent(cgrp));
/* put the base reference */
@@ -4814,23 +4808,10 @@ static int cgroup_rmdir(struct kernfs_node *kn)
cgrp = cgroup_kn_lock_live(kn);
if (!cgrp)
return 0;
- cgroup_get(cgrp); /* for @kn->priv clearing */
ret = cgroup_destroy_locked(cgrp);
cgroup_kn_unlock(kn);
-
- /*
- * There are two control paths which try to determine cgroup from
- * dentry without going through kernfs - cgroupstats_build() and
- * css_tryget_online_from_dir(). Those are supported by RCU
- * protecting clearing of cgrp->kn->priv backpointer, which should
- * happen after all files under it have been removed.
- */
- if (!ret)
- RCU_INIT_POINTER(*(void __rcu __force **)&kn->priv, NULL);
-
- cgroup_put(cgrp);
return ret;
}
@@ -5034,12 +5015,9 @@ core_initcall(cgroup_wq_init);
* - Print task's cgroup paths into seq_file, one line for each hierarchy
* - Used for /proc/<pid>/cgroup.
*/
-
-/* TODO: Use a proper seq_file iterator */
-int proc_cgroup_show(struct seq_file *m, void *v)
+int proc_cgroup_show(struct seq_file *m, struct pid_namespace *ns,
+ struct pid *pid, struct task_struct *tsk)
{
- struct pid *pid;
- struct task_struct *tsk;
char *buf, *path;
int retval;
struct cgroup_root *root;
@@ -5049,14 +5027,6 @@ int proc_cgroup_show(struct seq_file *m, void *v)
if (!buf)
goto out;
- retval = -ESRCH;
- pid = m->private;
- tsk = get_pid_task(pid, PIDTYPE_PID);
- if (!tsk)
- goto out_free;
-
- retval = 0;
-
mutex_lock(&cgroup_mutex);
down_read(&css_set_rwsem);
@@ -5086,11 +5056,10 @@ int proc_cgroup_show(struct seq_file *m, void *v)
seq_putc(m, '\n');
}
+ retval = 0;
out_unlock:
up_read(&css_set_rwsem);
mutex_unlock(&cgroup_mutex);
- put_task_struct(tsk);
-out_free:
kfree(buf);
out:
return retval;
@@ -5161,7 +5130,7 @@ void cgroup_post_fork(struct task_struct *child)
int i;
/*
- * This may race against cgroup_enable_task_cg_links(). As that
+ * This may race against cgroup_enable_task_cg_lists(). As that
* function sets use_task_css_set_links before grabbing
* tasklist_lock and we just went through tasklist_lock to add
* @child, it's guaranteed that either we see the set
@@ -5176,7 +5145,7 @@ void cgroup_post_fork(struct task_struct *child)
* when implementing operations which need to migrate all tasks of
* a cgroup to another.
*
- * Note that if we lose to cgroup_enable_task_cg_links(), @child
+ * Note that if we lose to cgroup_enable_task_cg_lists(), @child
* will remain in init_css_set. This is safe because all tasks are
* in the init_css_set before cg_links is enabled and there's no
* operation which transfers all tasks out of init_css_set.
@@ -5260,30 +5229,14 @@ void cgroup_exit(struct task_struct *tsk)
}
if (put_cset)
- put_css_set(cset, true);
+ put_css_set(cset);
}
static void check_for_release(struct cgroup *cgrp)
{
- if (cgroup_is_releasable(cgrp) && list_empty(&cgrp->cset_links) &&
- !css_has_online_children(&cgrp->self)) {
- /*
- * Control Group is currently removeable. If it's not
- * already queued for a userspace notification, queue
- * it now
- */
- int need_schedule_work = 0;
-
- raw_spin_lock(&release_list_lock);
- if (!cgroup_is_dead(cgrp) &&
- list_empty(&cgrp->release_list)) {
- list_add(&cgrp->release_list, &release_list);
- need_schedule_work = 1;
- }
- raw_spin_unlock(&release_list_lock);
- if (need_schedule_work)
- schedule_work(&release_agent_work);
- }
+ if (notify_on_release(cgrp) && !cgroup_has_tasks(cgrp) &&
+ !css_has_online_children(&cgrp->self) && !cgroup_is_dead(cgrp))
+ schedule_work(&cgrp->release_agent_work);
}
/*
@@ -5311,52 +5264,39 @@ static void check_for_release(struct cgroup *cgrp)
*/
static void cgroup_release_agent(struct work_struct *work)
{
- BUG_ON(work != &release_agent_work);
+ struct cgroup *cgrp =
+ container_of(work, struct cgroup, release_agent_work);
+ char *pathbuf = NULL, *agentbuf = NULL, *path;
+ char *argv[3], *envp[3];
+
mutex_lock(&cgroup_mutex);
- raw_spin_lock(&release_list_lock);
- while (!list_empty(&release_list)) {
- char *argv[3], *envp[3];
- int i;
- char *pathbuf = NULL, *agentbuf = NULL, *path;
- struct cgroup *cgrp = list_entry(release_list.next,
- struct cgroup,
- release_list);
- list_del_init(&cgrp->release_list);
- raw_spin_unlock(&release_list_lock);
- pathbuf = kmalloc(PATH_MAX, GFP_KERNEL);
- if (!pathbuf)
- goto continue_free;
- path = cgroup_path(cgrp, pathbuf, PATH_MAX);
- if (!path)
- goto continue_free;
- agentbuf = kstrdup(cgrp->root->release_agent_path, GFP_KERNEL);
- if (!agentbuf)
- goto continue_free;
-
- i = 0;
- argv[i++] = agentbuf;
- argv[i++] = path;
- argv[i] = NULL;
-
- i = 0;
- /* minimal command environment */
- envp[i++] = "HOME=/";
- envp[i++] = "PATH=/sbin:/bin:/usr/sbin:/usr/bin";
- envp[i] = NULL;
-
- /* Drop the lock while we invoke the usermode helper,
- * since the exec could involve hitting disk and hence
- * be a slow process */
- mutex_unlock(&cgroup_mutex);
- call_usermodehelper(argv[0], argv, envp, UMH_WAIT_EXEC);
- mutex_lock(&cgroup_mutex);
- continue_free:
- kfree(pathbuf);
- kfree(agentbuf);
- raw_spin_lock(&release_list_lock);
- }
- raw_spin_unlock(&release_list_lock);
+
+ pathbuf = kmalloc(PATH_MAX, GFP_KERNEL);
+ agentbuf = kstrdup(cgrp->root->release_agent_path, GFP_KERNEL);
+ if (!pathbuf || !agentbuf)
+ goto out;
+
+ path = cgroup_path(cgrp, pathbuf, PATH_MAX);
+ if (!path)
+ goto out;
+
+ argv[0] = agentbuf;
+ argv[1] = path;
+ argv[2] = NULL;
+
+ /* minimal command environment */
+ envp[0] = "HOME=/";
+ envp[1] = "PATH=/sbin:/bin:/usr/sbin:/usr/bin";
+ envp[2] = NULL;
+
mutex_unlock(&cgroup_mutex);
+ call_usermodehelper(argv[0], argv, envp, UMH_WAIT_EXEC);
+ goto out_free;
+out:
+ mutex_unlock(&cgroup_mutex);
+out_free:
+ kfree(agentbuf);
+ kfree(pathbuf);
}
static int __init cgroup_disable(char *str)
@@ -5416,7 +5356,7 @@ struct cgroup_subsys_state *css_tryget_online_from_dir(struct dentry *dentry,
/*
* This path doesn't originate from kernfs and @kn could already
* have been or be removed at any point. @kn->priv is RCU
- * protected for this access. See cgroup_rmdir() for details.
+ * protected for this access. See css_release_work_fn() for details.
*/
cgrp = rcu_dereference(kn->priv);
if (cgrp)
@@ -5544,7 +5484,8 @@ static int cgroup_css_links_read(struct seq_file *seq, void *v)
static u64 releasable_read(struct cgroup_subsys_state *css, struct cftype *cft)
{
- return test_bit(CGRP_RELEASABLE, &css->cgroup->flags);
+ return (!cgroup_has_tasks(css->cgroup) &&
+ !css_has_online_children(&css->cgroup->self));
}
static struct cftype debug_files[] = {
diff --git a/kernel/compat.c b/kernel/compat.c
index 633394f442f8..ebb3c369d03d 100644
--- a/kernel/compat.c
+++ b/kernel/compat.c
@@ -226,7 +226,7 @@ static long compat_nanosleep_restart(struct restart_block *restart)
ret = hrtimer_nanosleep_restart(restart);
set_fs(oldfs);
- if (ret) {
+ if (ret == -ERESTART_RESTARTBLOCK) {
rmtp = restart->nanosleep.compat_rmtp;
if (rmtp && compat_put_timespec(&rmt, rmtp))
@@ -256,7 +256,26 @@ COMPAT_SYSCALL_DEFINE2(nanosleep, struct compat_timespec __user *, rqtp,
HRTIMER_MODE_REL, CLOCK_MONOTONIC);
set_fs(oldfs);
- if (ret) {
+ /*
+ * hrtimer_nanosleep() can only return 0 or
+ * -ERESTART_RESTARTBLOCK here because:
+ *
+ * - we call it with HRTIMER_MODE_REL and therefor exclude the
+ * -ERESTARTNOHAND return path.
+ *
+ * - we supply the rmtp argument from the task stack (due to
+ * the necessary compat conversion. So the update cannot
+ * fail, which excludes the -EFAULT return path as well. If
+ * it fails nevertheless we have a bigger problem and wont
+ * reach this place anymore.
+ *
+ * - if the return value is 0, we do not have to update rmtp
+ * because there is no remaining time.
+ *
+ * We check for -ERESTART_RESTARTBLOCK nevertheless if the
+ * core implementation decides to return random nonsense.
+ */
+ if (ret == -ERESTART_RESTARTBLOCK) {
struct restart_block *restart
= &current_thread_info()->restart_block;
@@ -266,7 +285,6 @@ COMPAT_SYSCALL_DEFINE2(nanosleep, struct compat_timespec __user *, rqtp,
if (rmtp && compat_put_timespec(&rmt, rmtp))
return -EFAULT;
}
-
return ret;
}
diff --git a/kernel/configs/tiny.config b/kernel/configs/tiny.config
new file mode 100644
index 000000000000..c2de56ab0fce
--- /dev/null
+++ b/kernel/configs/tiny.config
@@ -0,0 +1,4 @@
+CONFIG_CC_OPTIMIZE_FOR_SIZE=y
+CONFIG_KERNEL_XZ=y
+CONFIG_OPTIMIZE_INLINING=y
+CONFIG_SLOB=y
diff --git a/kernel/cpu.c b/kernel/cpu.c
index 81e2a388a0f6..356450f09c1f 100644
--- a/kernel/cpu.c
+++ b/kernel/cpu.c
@@ -79,6 +79,8 @@ static struct {
/* Lockdep annotations for get/put_online_cpus() and cpu_hotplug_begin/end() */
#define cpuhp_lock_acquire_read() lock_map_acquire_read(&cpu_hotplug.dep_map)
+#define cpuhp_lock_acquire_tryread() \
+ lock_map_acquire_tryread(&cpu_hotplug.dep_map)
#define cpuhp_lock_acquire() lock_map_acquire(&cpu_hotplug.dep_map)
#define cpuhp_lock_release() lock_map_release(&cpu_hotplug.dep_map)
@@ -91,10 +93,22 @@ void get_online_cpus(void)
mutex_lock(&cpu_hotplug.lock);
cpu_hotplug.refcount++;
mutex_unlock(&cpu_hotplug.lock);
-
}
EXPORT_SYMBOL_GPL(get_online_cpus);
+bool try_get_online_cpus(void)
+{
+ if (cpu_hotplug.active_writer == current)
+ return true;
+ if (!mutex_trylock(&cpu_hotplug.lock))
+ return false;
+ cpuhp_lock_acquire_tryread();
+ cpu_hotplug.refcount++;
+ mutex_unlock(&cpu_hotplug.lock);
+ return true;
+}
+EXPORT_SYMBOL_GPL(try_get_online_cpus);
+
void put_online_cpus(void)
{
if (cpu_hotplug.active_writer == current)
diff --git a/kernel/cpuset.c b/kernel/cpuset.c
index 22874d7cf2c0..1f107c74087b 100644
--- a/kernel/cpuset.c
+++ b/kernel/cpuset.c
@@ -365,13 +365,14 @@ static void cpuset_update_task_spread_flag(struct cpuset *cs,
struct task_struct *tsk)
{
if (is_spread_page(cs))
- tsk->flags |= PF_SPREAD_PAGE;
+ task_set_spread_page(tsk);
else
- tsk->flags &= ~PF_SPREAD_PAGE;
+ task_clear_spread_page(tsk);
+
if (is_spread_slab(cs))
- tsk->flags |= PF_SPREAD_SLAB;
+ task_set_spread_slab(tsk);
else
- tsk->flags &= ~PF_SPREAD_SLAB;
+ task_clear_spread_slab(tsk);
}
/*
@@ -2729,10 +2730,9 @@ void __cpuset_memory_pressure_bump(void)
* and we take cpuset_mutex, keeping cpuset_attach() from changing it
* anyway.
*/
-int proc_cpuset_show(struct seq_file *m, void *unused_v)
+int proc_cpuset_show(struct seq_file *m, struct pid_namespace *ns,
+ struct pid *pid, struct task_struct *tsk)
{
- struct pid *pid;
- struct task_struct *tsk;
char *buf, *p;
struct cgroup_subsys_state *css;
int retval;
@@ -2742,24 +2742,16 @@ int proc_cpuset_show(struct seq_file *m, void *unused_v)
if (!buf)
goto out;
- retval = -ESRCH;
- pid = m->private;
- tsk = get_pid_task(pid, PIDTYPE_PID);
- if (!tsk)
- goto out_free;
-
retval = -ENAMETOOLONG;
rcu_read_lock();
css = task_css(tsk, cpuset_cgrp_id);
p = cgroup_path(css->cgroup, buf, PATH_MAX);
rcu_read_unlock();
if (!p)
- goto out_put_task;
+ goto out_free;
seq_puts(m, p);
seq_putc(m, '\n');
retval = 0;
-out_put_task:
- put_task_struct(tsk);
out_free:
kfree(buf);
out:
diff --git a/kernel/crash_dump.c b/kernel/crash_dump.c
index c766ee54c0b1..b64e238b553b 100644
--- a/kernel/crash_dump.c
+++ b/kernel/crash_dump.c
@@ -18,6 +18,7 @@ unsigned long saved_max_pfn;
* it under CONFIG_CRASH_DUMP and not CONFIG_PROC_VMCORE.
*/
unsigned long long elfcorehdr_addr = ELFCORE_ADDR_MAX;
+EXPORT_SYMBOL_GPL(elfcorehdr_addr);
/*
* stores the size of elf header of crash image
diff --git a/kernel/debug/kdb/kdb_bp.c b/kernel/debug/kdb/kdb_bp.c
index 70a504601dc3..b20d544f20c2 100644
--- a/kernel/debug/kdb/kdb_bp.c
+++ b/kernel/debug/kdb/kdb_bp.c
@@ -52,11 +52,11 @@ static int kdb_parsebp(int argc, const char **argv, int *nextargp, kdb_bp_t *bp)
bp->bph_length = 1;
if ((argc + 1) != nextarg) {
- if (strnicmp(argv[nextarg], "datar", sizeof("datar")) == 0)
+ if (strncasecmp(argv[nextarg], "datar", sizeof("datar")) == 0)
bp->bp_type = BP_ACCESS_WATCHPOINT;
- else if (strnicmp(argv[nextarg], "dataw", sizeof("dataw")) == 0)
+ else if (strncasecmp(argv[nextarg], "dataw", sizeof("dataw")) == 0)
bp->bp_type = BP_WRITE_WATCHPOINT;
- else if (strnicmp(argv[nextarg], "inst", sizeof("inst")) == 0)
+ else if (strncasecmp(argv[nextarg], "inst", sizeof("inst")) == 0)
bp->bp_type = BP_HARDWARE_BREAKPOINT;
else
return KDB_ARGCOUNT;
diff --git a/kernel/events/callchain.c b/kernel/events/callchain.c
index c4f63e68a35c..d659487254d5 100644
--- a/kernel/events/callchain.c
+++ b/kernel/events/callchain.c
@@ -52,7 +52,7 @@ static void release_callchain_buffers(void)
struct callchain_cpus_entries *entries;
entries = callchain_cpus_entries;
- rcu_assign_pointer(callchain_cpus_entries, NULL);
+ RCU_INIT_POINTER(callchain_cpus_entries, NULL);
call_rcu(&entries->rcu_head, release_callchain_buffers_rcu);
}
diff --git a/kernel/events/core.c b/kernel/events/core.c
index 4d44e40a0483..1425d07018de 100644
--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -41,11 +41,14 @@
#include <linux/cgroup.h>
#include <linux/module.h>
#include <linux/mman.h>
+#include <linux/compat.h>
#include "internal.h"
#include <asm/irq_regs.h>
+static struct workqueue_struct *perf_wq;
+
struct remote_function_call {
struct task_struct *p;
int (*func)(void *info);
@@ -119,6 +122,13 @@ static int cpu_function_call(int cpu, int (*func) (void *info), void *info)
return data.ret;
}
+#define EVENT_OWNER_KERNEL ((void *) -1)
+
+static bool is_kernel_event(struct perf_event *event)
+{
+ return event->owner == EVENT_OWNER_KERNEL;
+}
+
#define PERF_FLAG_ALL (PERF_FLAG_FD_NO_GROUP |\
PERF_FLAG_FD_OUTPUT |\
PERF_FLAG_PID_CGROUP |\
@@ -391,14 +401,9 @@ perf_cgroup_match(struct perf_event *event)
event->cgrp->css.cgroup);
}
-static inline void perf_put_cgroup(struct perf_event *event)
-{
- css_put(&event->cgrp->css);
-}
-
static inline void perf_detach_cgroup(struct perf_event *event)
{
- perf_put_cgroup(event);
+ css_put(&event->cgrp->css);
event->cgrp = NULL;
}
@@ -901,13 +906,23 @@ static void put_ctx(struct perf_event_context *ctx)
}
}
-static void unclone_ctx(struct perf_event_context *ctx)
+/*
+ * This must be done under the ctx->lock, such as to serialize against
+ * context_equiv(), therefore we cannot call put_ctx() since that might end up
+ * calling scheduler related locks and ctx->lock nests inside those.
+ */
+static __must_check struct perf_event_context *
+unclone_ctx(struct perf_event_context *ctx)
{
- if (ctx->parent_ctx) {
- put_ctx(ctx->parent_ctx);
+ struct perf_event_context *parent_ctx = ctx->parent_ctx;
+
+ lockdep_assert_held(&ctx->lock);
+
+ if (parent_ctx)
ctx->parent_ctx = NULL;
- }
ctx->generation++;
+
+ return parent_ctx;
}
static u32 perf_event_pid(struct perf_event *event, struct task_struct *p)
@@ -1374,6 +1389,45 @@ out:
perf_event__header_size(tmp);
}
+/*
+ * User event without the task.
+ */
+static bool is_orphaned_event(struct perf_event *event)
+{
+ return event && !is_kernel_event(event) && !event->owner;
+}
+
+/*
+ * Event has a parent but parent's task finished and it's
+ * alive only because of children holding refference.
+ */
+static bool is_orphaned_child(struct perf_event *event)
+{
+ return is_orphaned_event(event->parent);
+}
+
+static void orphans_remove_work(struct work_struct *work);
+
+static void schedule_orphans_remove(struct perf_event_context *ctx)
+{
+ if (!ctx->task || ctx->orphans_remove_sched || !perf_wq)
+ return;
+
+ if (queue_delayed_work(perf_wq, &ctx->orphans_remove, 1)) {
+ get_ctx(ctx);
+ ctx->orphans_remove_sched = true;
+ }
+}
+
+static int __init perf_workqueue_init(void)
+{
+ perf_wq = create_singlethread_workqueue("perf");
+ WARN(!perf_wq, "failed to create perf workqueue\n");
+ return perf_wq ? 0 : -1;
+}
+
+core_initcall(perf_workqueue_init);
+
static inline int
event_filter_match(struct perf_event *event)
{
@@ -1423,6 +1477,9 @@ event_sched_out(struct perf_event *event,
if (event->attr.exclusive || !cpuctx->active_oncpu)
cpuctx->exclusive = 0;
+ if (is_orphaned_child(event))
+ schedule_orphans_remove(ctx);
+
perf_pmu_enable(event->pmu);
}
@@ -1523,6 +1580,11 @@ retry:
*/
if (ctx->is_active) {
raw_spin_unlock_irq(&ctx->lock);
+ /*
+ * Reload the task pointer, it might have been changed by
+ * a concurrent perf_event_context_sched_out().
+ */
+ task = ctx->task;
goto retry;
}
@@ -1725,6 +1787,9 @@ event_sched_in(struct perf_event *event,
if (event->attr.exclusive)
cpuctx->exclusive = 1;
+ if (is_orphaned_child(event))
+ schedule_orphans_remove(ctx);
+
out:
perf_pmu_enable(event->pmu);
@@ -1966,6 +2031,11 @@ retry:
*/
if (ctx->is_active) {
raw_spin_unlock_irq(&ctx->lock);
+ /*
+ * Reload the task pointer, it might have been changed by
+ * a concurrent perf_event_context_sched_out().
+ */
+ task = ctx->task;
goto retry;
}
@@ -2199,6 +2269,9 @@ static void ctx_sched_out(struct perf_event_context *ctx,
static int context_equiv(struct perf_event_context *ctx1,
struct perf_event_context *ctx2)
{
+ lockdep_assert_held(&ctx1->lock);
+ lockdep_assert_held(&ctx2->lock);
+
/* Pinning disables the swap optimization */
if (ctx1->pin_count || ctx2->pin_count)
return 0;
@@ -2320,7 +2393,7 @@ static void perf_event_context_sched_out(struct task_struct *task, int ctxn,
next_parent = rcu_dereference(next_ctx->parent_ctx);
/* If neither context have a parent context; they cannot be clones. */
- if (!parent || !next_parent)
+ if (!parent && !next_parent)
goto unlock;
if (next_parent == ctx || next_ctx == parent || next_parent == parent) {
@@ -2932,6 +3005,7 @@ static int event_enable_on_exec(struct perf_event *event,
*/
static void perf_event_enable_on_exec(struct perf_event_context *ctx)
{
+ struct perf_event_context *clone_ctx = NULL;
struct perf_event *event;
unsigned long flags;
int enabled = 0;
@@ -2963,7 +3037,7 @@ static void perf_event_enable_on_exec(struct perf_event_context *ctx)
* Unclone this context if we enabled any event.
*/
if (enabled)
- unclone_ctx(ctx);
+ clone_ctx = unclone_ctx(ctx);
raw_spin_unlock(&ctx->lock);
@@ -2973,6 +3047,9 @@ static void perf_event_enable_on_exec(struct perf_event_context *ctx)
perf_event_context_sched_in(ctx, ctx->task);
out:
local_irq_restore(flags);
+
+ if (clone_ctx)
+ put_ctx(clone_ctx);
}
void perf_event_exec(void)
@@ -3067,6 +3144,7 @@ static void __perf_event_init_context(struct perf_event_context *ctx)
INIT_LIST_HEAD(&ctx->flexible_groups);
INIT_LIST_HEAD(&ctx->event_list);
atomic_set(&ctx->refcount, 1);
+ INIT_DELAYED_WORK(&ctx->orphans_remove, orphans_remove_work);
}
static struct perf_event_context *
@@ -3124,7 +3202,7 @@ errout:
static struct perf_event_context *
find_get_context(struct pmu *pmu, struct task_struct *task, int cpu)
{
- struct perf_event_context *ctx;
+ struct perf_event_context *ctx, *clone_ctx = NULL;
struct perf_cpu_context *cpuctx;
unsigned long flags;
int ctxn, err;
@@ -3158,9 +3236,12 @@ find_get_context(struct pmu *pmu, struct task_struct *task, int cpu)
retry:
ctx = perf_lock_task_context(task, ctxn, &flags);
if (ctx) {
- unclone_ctx(ctx);
+ clone_ctx = unclone_ctx(ctx);
++ctx->pin_count;
raw_spin_unlock_irqrestore(&ctx->lock, flags);
+
+ if (clone_ctx)
+ put_ctx(clone_ctx);
} else {
ctx = alloc_perf_context(pmu, task);
err = -ENOMEM;
@@ -3312,16 +3393,12 @@ static void free_event(struct perf_event *event)
}
/*
- * Called when the last reference to the file is gone.
+ * Remove user event from the owner task.
*/
-static void put_event(struct perf_event *event)
+static void perf_remove_from_owner(struct perf_event *event)
{
- struct perf_event_context *ctx = event->ctx;
struct task_struct *owner;
- if (!atomic_long_dec_and_test(&event->refcount))
- return;
-
rcu_read_lock();
owner = ACCESS_ONCE(event->owner);
/*
@@ -3354,6 +3431,20 @@ static void put_event(struct perf_event *event)
mutex_unlock(&owner->perf_event_mutex);
put_task_struct(owner);
}
+}
+
+/*
+ * Called when the last reference to the file is gone.
+ */
+static void put_event(struct perf_event *event)
+{
+ struct perf_event_context *ctx = event->ctx;
+
+ if (!atomic_long_dec_and_test(&event->refcount))
+ return;
+
+ if (!is_kernel_event(event))
+ perf_remove_from_owner(event);
WARN_ON_ONCE(ctx->parent_ctx);
/*
@@ -3388,6 +3479,42 @@ static int perf_release(struct inode *inode, struct file *file)
return 0;
}
+/*
+ * Remove all orphanes events from the context.
+ */
+static void orphans_remove_work(struct work_struct *work)
+{
+ struct perf_event_context *ctx;
+ struct perf_event *event, *tmp;
+
+ ctx = container_of(work, struct perf_event_context,
+ orphans_remove.work);
+
+ mutex_lock(&ctx->mutex);
+ list_for_each_entry_safe(event, tmp, &ctx->event_list, event_entry) {
+ struct perf_event *parent_event = event->parent;
+
+ if (!is_orphaned_child(event))
+ continue;
+
+ perf_remove_from_context(event, true);
+
+ mutex_lock(&parent_event->child_mutex);
+ list_del_init(&event->child_list);
+ mutex_unlock(&parent_event->child_mutex);
+
+ free_event(event);
+ put_event(parent_event);
+ }
+
+ raw_spin_lock_irq(&ctx->lock);
+ ctx->orphans_remove_sched = false;
+ raw_spin_unlock_irq(&ctx->lock);
+ mutex_unlock(&ctx->mutex);
+
+ put_ctx(ctx);
+}
+
u64 perf_event_read_value(struct perf_event *event, u64 *enabled, u64 *running)
{
struct perf_event *child;
@@ -3485,6 +3612,19 @@ static int perf_event_read_one(struct perf_event *event,
return n * sizeof(u64);
}
+static bool is_event_hup(struct perf_event *event)
+{
+ bool no_children;
+
+ if (event->state != PERF_EVENT_STATE_EXIT)
+ return false;
+
+ mutex_lock(&event->child_mutex);
+ no_children = list_empty(&event->child_list);
+ mutex_unlock(&event->child_mutex);
+ return no_children;
+}
+
/*
* Read the performance event - simple non blocking version for now
*/
@@ -3526,7 +3666,12 @@ static unsigned int perf_poll(struct file *file, poll_table *wait)
{
struct perf_event *event = file->private_data;
struct ring_buffer *rb;
- unsigned int events = POLL_HUP;
+ unsigned int events = POLLHUP;
+
+ poll_wait(file, &event->waitq, wait);
+
+ if (is_event_hup(event))
+ return events;
/*
* Pin the event->rb by taking event->mmap_mutex; otherwise
@@ -3537,9 +3682,6 @@ static unsigned int perf_poll(struct file *file, poll_table *wait)
if (rb)
events = atomic_xchg(&rb->poll, 0);
mutex_unlock(&event->mmap_mutex);
-
- poll_wait(file, &event->waitq, wait);
-
return events;
}
@@ -3717,6 +3859,26 @@ static long perf_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
return 0;
}
+#ifdef CONFIG_COMPAT
+static long perf_compat_ioctl(struct file *file, unsigned int cmd,
+ unsigned long arg)
+{
+ switch (_IOC_NR(cmd)) {
+ case _IOC_NR(PERF_EVENT_IOC_SET_FILTER):
+ case _IOC_NR(PERF_EVENT_IOC_ID):
+ /* Fix up pointer size (usually 4 -> 8 in 32-on-64-bit case */
+ if (_IOC_SIZE(cmd) == sizeof(compat_uptr_t)) {
+ cmd &= ~IOCSIZE_MASK;
+ cmd |= sizeof(void *) << IOCSIZE_SHIFT;
+ }
+ break;
+ }
+ return perf_ioctl(file, cmd, arg);
+}
+#else
+# define perf_compat_ioctl NULL
+#endif
+
int perf_event_task_enable(void)
{
struct perf_event *event;
@@ -4222,7 +4384,7 @@ static const struct file_operations perf_fops = {
.read = perf_read,
.poll = perf_poll,
.unlocked_ioctl = perf_ioctl,
- .compat_ioctl = perf_ioctl,
+ .compat_ioctl = perf_compat_ioctl,
.mmap = perf_mmap,
.fasync = perf_fasync,
};
@@ -5783,7 +5945,7 @@ static void swevent_hlist_release(struct swevent_htable *swhash)
if (!hlist)
return;
- rcu_assign_pointer(swhash->swevent_hlist, NULL);
+ RCU_INIT_POINTER(swhash->swevent_hlist, NULL);
kfree_rcu(hlist, rcu_head);
}
@@ -7366,6 +7528,9 @@ perf_event_create_kernel_counter(struct perf_event_attr *attr, int cpu,
goto err;
}
+ /* Mark owner so we could distinguish it from user events. */
+ event->owner = EVENT_OWNER_KERNEL;
+
account_event(event);
ctx = find_get_context(event->pmu, task, cpu);
@@ -7453,6 +7618,12 @@ static void sync_child_event(struct perf_event *child_event,
mutex_unlock(&parent_event->child_mutex);
/*
+ * Make sure user/parent get notified, that we just
+ * lost one event.
+ */
+ perf_event_wakeup(parent_event);
+
+ /*
* Release the parent event, if this was the last
* reference to it.
*/
@@ -7486,13 +7657,16 @@ __perf_event_exit_task(struct perf_event *child_event,
if (child_event->parent) {
sync_child_event(child_event, child);
free_event(child_event);
+ } else {
+ child_event->state = PERF_EVENT_STATE_EXIT;
+ perf_event_wakeup(child_event);
}
}
static void perf_event_exit_task_context(struct task_struct *child, int ctxn)
{
struct perf_event *child_event, *next;
- struct perf_event_context *child_ctx, *parent_ctx;
+ struct perf_event_context *child_ctx, *clone_ctx = NULL;
unsigned long flags;
if (likely(!child->perf_event_ctxp[ctxn])) {
@@ -7519,28 +7693,16 @@ static void perf_event_exit_task_context(struct task_struct *child, int ctxn)
child->perf_event_ctxp[ctxn] = NULL;
/*
- * In order to avoid freeing: child_ctx->parent_ctx->task
- * under perf_event_context::lock, grab another reference.
- */
- parent_ctx = child_ctx->parent_ctx;
- if (parent_ctx)
- get_ctx(parent_ctx);
-
- /*
* If this context is a clone; unclone it so it can't get
* swapped to another process while we're removing all
* the events from it.
*/
- unclone_ctx(child_ctx);
+ clone_ctx = unclone_ctx(child_ctx);
update_context_time(child_ctx);
raw_spin_unlock_irqrestore(&child_ctx->lock, flags);
- /*
- * Now that we no longer hold perf_event_context::lock, drop
- * our extra child_ctx->parent_ctx reference.
- */
- if (parent_ctx)
- put_ctx(parent_ctx);
+ if (clone_ctx)
+ put_ctx(clone_ctx);
/*
* Report the task dead after unscheduling the events so that we
@@ -7669,6 +7831,7 @@ inherit_event(struct perf_event *parent_event,
struct perf_event *group_leader,
struct perf_event_context *child_ctx)
{
+ enum perf_event_active_state parent_state = parent_event->state;
struct perf_event *child_event;
unsigned long flags;
@@ -7689,7 +7852,8 @@ inherit_event(struct perf_event *parent_event,
if (IS_ERR(child_event))
return child_event;
- if (!atomic_long_inc_not_zero(&parent_event->refcount)) {
+ if (is_orphaned_event(parent_event) ||
+ !atomic_long_inc_not_zero(&parent_event->refcount)) {
free_event(child_event);
return NULL;
}
@@ -7701,7 +7865,7 @@ inherit_event(struct perf_event *parent_event,
* not its attr.disabled bit. We hold the parent's mutex,
* so we won't race with perf_event_{en, dis}able_family.
*/
- if (parent_event->state >= PERF_EVENT_STATE_INACTIVE)
+ if (parent_state >= PERF_EVENT_STATE_INACTIVE)
child_event->state = PERF_EVENT_STATE_INACTIVE;
else
child_event->state = PERF_EVENT_STATE_OFF;
@@ -7917,8 +8081,10 @@ int perf_event_init_task(struct task_struct *child)
for_each_task_context_nr(ctxn) {
ret = perf_event_init_context(child, ctxn);
- if (ret)
+ if (ret) {
+ perf_event_free_task(child);
return ret;
+ }
}
return 0;
diff --git a/kernel/exit.c b/kernel/exit.c
index 32c58f7433a3..5d30019ff953 100644
--- a/kernel/exit.c
+++ b/kernel/exit.c
@@ -115,32 +115,33 @@ static void __exit_signal(struct task_struct *tsk)
if (tsk == sig->curr_target)
sig->curr_target = next_thread(tsk);
- /*
- * Accumulate here the counters for all threads but the
- * group leader as they die, so they can be added into
- * the process-wide totals when those are taken.
- * The group leader stays around as a zombie as long
- * as there are other threads. When it gets reaped,
- * the exit.c code will add its counts into these totals.
- * We won't ever get here for the group leader, since it
- * will have been the last reference on the signal_struct.
- */
- task_cputime(tsk, &utime, &stime);
- sig->utime += utime;
- sig->stime += stime;
- sig->gtime += task_gtime(tsk);
- sig->min_flt += tsk->min_flt;
- sig->maj_flt += tsk->maj_flt;
- sig->nvcsw += tsk->nvcsw;
- sig->nivcsw += tsk->nivcsw;
- sig->inblock += task_io_get_inblock(tsk);
- sig->oublock += task_io_get_oublock(tsk);
- task_io_accounting_add(&sig->ioac, &tsk->ioac);
- sig->sum_sched_runtime += tsk->se.sum_exec_runtime;
}
+ /*
+ * Accumulate here the counters for all threads but the group leader
+ * as they die, so they can be added into the process-wide totals
+ * when those are taken. The group leader stays around as a zombie as
+ * long as there are other threads. When it gets reaped, the exit.c
+ * code will add its counts into these totals. We won't ever get here
+ * for the group leader, since it will have been the last reference on
+ * the signal_struct.
+ */
+ task_cputime(tsk, &utime, &stime);
+ write_seqlock(&sig->stats_lock);
+ sig->utime += utime;
+ sig->stime += stime;
+ sig->gtime += task_gtime(tsk);
+ sig->min_flt += tsk->min_flt;
+ sig->maj_flt += tsk->maj_flt;
+ sig->nvcsw += tsk->nvcsw;
+ sig->nivcsw += tsk->nivcsw;
+ sig->inblock += task_io_get_inblock(tsk);
+ sig->oublock += task_io_get_oublock(tsk);
+ task_io_accounting_add(&sig->ioac, &tsk->ioac);
+ sig->sum_sched_runtime += tsk->se.sum_exec_runtime;
sig->nr_threads--;
__unhash_process(tsk, group_dead);
+ write_sequnlock(&sig->stats_lock);
/*
* Do this under ->siglock, we can race with another thread
@@ -667,6 +668,7 @@ void do_exit(long code)
{
struct task_struct *tsk = current;
int group_dead;
+ TASKS_RCU(int tasks_rcu_i);
profile_task_exit(tsk);
@@ -775,6 +777,7 @@ void do_exit(long code)
*/
flush_ptrace_hw_breakpoint(tsk);
+ TASKS_RCU(tasks_rcu_i = __srcu_read_lock(&tasks_rcu_exit_srcu));
exit_notify(tsk, group_dead);
proc_exit_connector(tsk);
#ifdef CONFIG_NUMA
@@ -814,6 +817,7 @@ void do_exit(long code)
if (tsk->nr_dirtied)
__this_cpu_add(dirty_throttle_leaks, tsk->nr_dirtied);
exit_rcu();
+ TASKS_RCU(__srcu_read_unlock(&tasks_rcu_exit_srcu, tasks_rcu_i));
/*
* The setting of TASK_RUNNING by try_to_wake_up() may be delayed
@@ -1043,6 +1047,7 @@ static int wait_task_zombie(struct wait_opts *wo, struct task_struct *p)
spin_lock_irq(&p->real_parent->sighand->siglock);
psig = p->real_parent->signal;
sig = p->signal;
+ write_seqlock(&psig->stats_lock);
psig->cutime += tgutime + sig->cutime;
psig->cstime += tgstime + sig->cstime;
psig->cgtime += task_gtime(p) + sig->gtime + sig->cgtime;
@@ -1065,6 +1070,7 @@ static int wait_task_zombie(struct wait_opts *wo, struct task_struct *p)
psig->cmaxrss = maxrss;
task_io_accounting_add(&psig->ioac, &p->ioac);
task_io_accounting_add(&psig->ioac, &sig->ioac);
+ write_sequnlock(&psig->stats_lock);
spin_unlock_irq(&p->real_parent->sighand->siglock);
}
diff --git a/kernel/fork.c b/kernel/fork.c
index 0cf9cdb6e491..9b7d746d6d62 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -294,11 +294,18 @@ int __weak arch_dup_task_struct(struct task_struct *dst,
return 0;
}
+void set_task_stack_end_magic(struct task_struct *tsk)
+{
+ unsigned long *stackend;
+
+ stackend = end_of_stack(tsk);
+ *stackend = STACK_END_MAGIC; /* for overflow detection */
+}
+
static struct task_struct *dup_task_struct(struct task_struct *orig)
{
struct task_struct *tsk;
struct thread_info *ti;
- unsigned long *stackend;
int node = tsk_fork_get_node(orig);
int err;
@@ -328,8 +335,7 @@ static struct task_struct *dup_task_struct(struct task_struct *orig)
setup_thread_stack(tsk, orig);
clear_user_return_notifier(tsk);
clear_tsk_need_resched(tsk);
- stackend = end_of_stack(tsk);
- *stackend = STACK_END_MAGIC; /* for overflow detection */
+ set_task_stack_end_magic(tsk);
#ifdef CONFIG_CC_STACKPROTECTOR
tsk->stack_canary = get_random_int();
@@ -601,9 +607,8 @@ static void check_mm(struct mm_struct *mm)
printk(KERN_ALERT "BUG: Bad rss-counter state "
"mm:%p idx:%d val:%ld\n", mm, i, x);
}
-
#if defined(CONFIG_TRANSPARENT_HUGEPAGE) && !USE_SPLIT_PMD_PTLOCKS
- VM_BUG_ON(mm->pmd_huge_pte);
+ VM_BUG_ON_MM(mm->pmd_huge_pte, mm);
#endif
}
@@ -1068,6 +1073,7 @@ static int copy_signal(unsigned long clone_flags, struct task_struct *tsk)
sig->curr_target = tsk;
init_sigpending(&sig->shared_pending);
INIT_LIST_HEAD(&sig->posix_timers);
+ seqlock_init(&sig->stats_lock);
hrtimer_init(&sig->real_timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
sig->real_timer.function = it_real_fn;
@@ -1360,7 +1366,7 @@ static struct task_struct *copy_process(unsigned long clone_flags,
goto bad_fork_cleanup_policy;
retval = audit_alloc(p);
if (retval)
- goto bad_fork_cleanup_policy;
+ goto bad_fork_cleanup_perf;
/* copy all the process information */
shm_init_task(p);
retval = copy_semundo(clone_flags, p);
@@ -1566,8 +1572,9 @@ bad_fork_cleanup_semundo:
exit_sem(p);
bad_fork_cleanup_audit:
audit_free(p);
-bad_fork_cleanup_policy:
+bad_fork_cleanup_perf:
perf_event_free_task(p);
+bad_fork_cleanup_policy:
#ifdef CONFIG_NUMA
mpol_put(p->mempolicy);
bad_fork_cleanup_threadgroup_lock:
diff --git a/kernel/futex.c b/kernel/futex.c
index d3a9d946d0b7..815d7af2ffe8 100644
--- a/kernel/futex.c
+++ b/kernel/futex.c
@@ -2592,6 +2592,7 @@ static int futex_wait_requeue_pi(u32 __user *uaddr, unsigned int flags,
* shared futexes. We need to compare the keys:
*/
if (match_futex(&q.key, &key2)) {
+ queue_unlock(hb);
ret = -EINVAL;
goto out_put_keys;
}
diff --git a/kernel/gcov/Kconfig b/kernel/gcov/Kconfig
index d04ce8ac4399..cf66c5c8458e 100644
--- a/kernel/gcov/Kconfig
+++ b/kernel/gcov/Kconfig
@@ -35,7 +35,7 @@ config GCOV_KERNEL
config GCOV_PROFILE_ALL
bool "Profile entire Kernel"
depends on GCOV_KERNEL
- depends on SUPERH || S390 || X86 || PPC || MICROBLAZE
+ depends on SUPERH || S390 || X86 || PPC || MICROBLAZE || ARM
default n
---help---
This options activates profiling for the entire kernel.
diff --git a/kernel/irq/Kconfig b/kernel/irq/Kconfig
index d269cecdfbf0..225086b2652e 100644
--- a/kernel/irq/Kconfig
+++ b/kernel/irq/Kconfig
@@ -55,6 +55,9 @@ config GENERIC_IRQ_CHIP
config IRQ_DOMAIN
bool
+config HANDLE_DOMAIN_IRQ
+ bool
+
config IRQ_DOMAIN_DEBUG
bool "Expose hardware/virtual IRQ mapping via debugfs"
depends on IRQ_DOMAIN && DEBUG_FS
diff --git a/kernel/irq/chip.c b/kernel/irq/chip.c
index cca7292fc61e..e5202f00cabc 100644
--- a/kernel/irq/chip.c
+++ b/kernel/irq/chip.c
@@ -342,6 +342,31 @@ static bool irq_check_poll(struct irq_desc *desc)
return irq_wait_for_poll(desc);
}
+static bool irq_may_run(struct irq_desc *desc)
+{
+ unsigned int mask = IRQD_IRQ_INPROGRESS | IRQD_WAKEUP_ARMED;
+
+ /*
+ * If the interrupt is not in progress and is not an armed
+ * wakeup interrupt, proceed.
+ */
+ if (!irqd_has_set(&desc->irq_data, mask))
+ return true;
+
+ /*
+ * If the interrupt is an armed wakeup source, mark it pending
+ * and suspended, disable it and notify the pm core about the
+ * event.
+ */
+ if (irq_pm_check_wakeup(desc))
+ return false;
+
+ /*
+ * Handle a potential concurrent poll on a different core.
+ */
+ return irq_check_poll(desc);
+}
+
/**
* handle_simple_irq - Simple and software-decoded IRQs.
* @irq: the interrupt number
@@ -359,9 +384,8 @@ handle_simple_irq(unsigned int irq, struct irq_desc *desc)
{
raw_spin_lock(&desc->lock);
- if (unlikely(irqd_irq_inprogress(&desc->irq_data)))
- if (!irq_check_poll(desc))
- goto out_unlock;
+ if (!irq_may_run(desc))
+ goto out_unlock;
desc->istate &= ~(IRQS_REPLAY | IRQS_WAITING);
kstat_incr_irqs_this_cpu(irq, desc);
@@ -412,9 +436,8 @@ handle_level_irq(unsigned int irq, struct irq_desc *desc)
raw_spin_lock(&desc->lock);
mask_ack_irq(desc);
- if (unlikely(irqd_irq_inprogress(&desc->irq_data)))
- if (!irq_check_poll(desc))
- goto out_unlock;
+ if (!irq_may_run(desc))
+ goto out_unlock;
desc->istate &= ~(IRQS_REPLAY | IRQS_WAITING);
kstat_incr_irqs_this_cpu(irq, desc);
@@ -485,9 +508,8 @@ handle_fasteoi_irq(unsigned int irq, struct irq_desc *desc)
raw_spin_lock(&desc->lock);
- if (unlikely(irqd_irq_inprogress(&desc->irq_data)))
- if (!irq_check_poll(desc))
- goto out;
+ if (!irq_may_run(desc))
+ goto out;
desc->istate &= ~(IRQS_REPLAY | IRQS_WAITING);
kstat_incr_irqs_this_cpu(irq, desc);
@@ -517,6 +539,7 @@ out:
chip->irq_eoi(&desc->irq_data);
raw_spin_unlock(&desc->lock);
}
+EXPORT_SYMBOL_GPL(handle_fasteoi_irq);
/**
* handle_edge_irq - edge type IRQ handler
@@ -540,19 +563,23 @@ handle_edge_irq(unsigned int irq, struct irq_desc *desc)
raw_spin_lock(&desc->lock);
desc->istate &= ~(IRQS_REPLAY | IRQS_WAITING);
+
+ if (!irq_may_run(desc)) {
+ desc->istate |= IRQS_PENDING;
+ mask_ack_irq(desc);
+ goto out_unlock;
+ }
+
/*
- * If we're currently running this IRQ, or its disabled,
- * we shouldn't process the IRQ. Mark it pending, handle
- * the necessary masking and go out
+ * If its disabled or no action available then mask it and get
+ * out of here.
*/
- if (unlikely(irqd_irq_disabled(&desc->irq_data) ||
- irqd_irq_inprogress(&desc->irq_data) || !desc->action)) {
- if (!irq_check_poll(desc)) {
- desc->istate |= IRQS_PENDING;
- mask_ack_irq(desc);
- goto out_unlock;
- }
+ if (irqd_irq_disabled(&desc->irq_data) || !desc->action) {
+ desc->istate |= IRQS_PENDING;
+ mask_ack_irq(desc);
+ goto out_unlock;
}
+
kstat_incr_irqs_this_cpu(irq, desc);
/* Start handling the irq */
@@ -601,18 +628,21 @@ void handle_edge_eoi_irq(unsigned int irq, struct irq_desc *desc)
raw_spin_lock(&desc->lock);
desc->istate &= ~(IRQS_REPLAY | IRQS_WAITING);
+
+ if (!irq_may_run(desc)) {
+ desc->istate |= IRQS_PENDING;
+ goto out_eoi;
+ }
+
/*
- * If we're currently running this IRQ, or its disabled,
- * we shouldn't process the IRQ. Mark it pending, handle
- * the necessary masking and go out
+ * If its disabled or no action available then mask it and get
+ * out of here.
*/
- if (unlikely(irqd_irq_disabled(&desc->irq_data) ||
- irqd_irq_inprogress(&desc->irq_data) || !desc->action)) {
- if (!irq_check_poll(desc)) {
- desc->istate |= IRQS_PENDING;
- goto out_eoi;
- }
+ if (irqd_irq_disabled(&desc->irq_data) || !desc->action) {
+ desc->istate |= IRQS_PENDING;
+ goto out_eoi;
}
+
kstat_incr_irqs_this_cpu(irq, desc);
do {
diff --git a/kernel/irq/devres.c b/kernel/irq/devres.c
index 1ef0606797c9..d5d0f7345c54 100644
--- a/kernel/irq/devres.c
+++ b/kernel/irq/devres.c
@@ -38,7 +38,7 @@ static int devm_irq_match(struct device *dev, void *res, void *data)
*
* Except for the extra @dev argument, this function takes the
* same arguments and performs the same function as
- * request_irq(). IRQs requested with this function will be
+ * request_threaded_irq(). IRQs requested with this function will be
* automatically freed on driver detach.
*
* If an IRQ allocated with this function needs to be freed
diff --git a/kernel/irq/internals.h b/kernel/irq/internals.h
index 099ea2e0eb88..4332d766619d 100644
--- a/kernel/irq/internals.h
+++ b/kernel/irq/internals.h
@@ -63,8 +63,8 @@ enum {
extern int __irq_set_trigger(struct irq_desc *desc, unsigned int irq,
unsigned long flags);
-extern void __disable_irq(struct irq_desc *desc, unsigned int irq, bool susp);
-extern void __enable_irq(struct irq_desc *desc, unsigned int irq, bool resume);
+extern void __disable_irq(struct irq_desc *desc, unsigned int irq);
+extern void __enable_irq(struct irq_desc *desc, unsigned int irq);
extern int irq_startup(struct irq_desc *desc, bool resend);
extern void irq_shutdown(struct irq_desc *desc);
@@ -194,3 +194,15 @@ static inline void kstat_incr_irqs_this_cpu(unsigned int irq, struct irq_desc *d
__this_cpu_inc(*desc->kstat_irqs);
__this_cpu_inc(kstat.irqs_sum);
}
+
+#ifdef CONFIG_PM_SLEEP
+bool irq_pm_check_wakeup(struct irq_desc *desc);
+void irq_pm_install_action(struct irq_desc *desc, struct irqaction *action);
+void irq_pm_remove_action(struct irq_desc *desc, struct irqaction *action);
+#else
+static inline bool irq_pm_check_wakeup(struct irq_desc *desc) { return false; }
+static inline void
+irq_pm_install_action(struct irq_desc *desc, struct irqaction *action) { }
+static inline void
+irq_pm_remove_action(struct irq_desc *desc, struct irqaction *action) { }
+#endif
diff --git a/kernel/irq/irqdesc.c b/kernel/irq/irqdesc.c
index 1487a123db5c..a1782f88f0af 100644
--- a/kernel/irq/irqdesc.c
+++ b/kernel/irq/irqdesc.c
@@ -14,6 +14,7 @@
#include <linux/kernel_stat.h>
#include <linux/radix-tree.h>
#include <linux/bitmap.h>
+#include <linux/irqdomain.h>
#include "internals.h"
@@ -336,6 +337,47 @@ int generic_handle_irq(unsigned int irq)
}
EXPORT_SYMBOL_GPL(generic_handle_irq);
+#ifdef CONFIG_HANDLE_DOMAIN_IRQ
+/**
+ * __handle_domain_irq - Invoke the handler for a HW irq belonging to a domain
+ * @domain: The domain where to perform the lookup
+ * @hwirq: The HW irq number to convert to a logical one
+ * @lookup: Whether to perform the domain lookup or not
+ * @regs: Register file coming from the low-level handling code
+ *
+ * Returns: 0 on success, or -EINVAL if conversion has failed
+ */
+int __handle_domain_irq(struct irq_domain *domain, unsigned int hwirq,
+ bool lookup, struct pt_regs *regs)
+{
+ struct pt_regs *old_regs = set_irq_regs(regs);
+ unsigned int irq = hwirq;
+ int ret = 0;
+
+ irq_enter();
+
+#ifdef CONFIG_IRQ_DOMAIN
+ if (lookup)
+ irq = irq_find_mapping(domain, hwirq);
+#endif
+
+ /*
+ * Some hardware gives randomly wrong interrupts. Rather
+ * than crashing, do something sensible.
+ */
+ if (unlikely(!irq || irq >= nr_irqs)) {
+ ack_bad_irq(irq);
+ ret = -EINVAL;
+ } else {
+ generic_handle_irq(irq);
+ }
+
+ irq_exit();
+ set_irq_regs(old_regs);
+ return ret;
+}
+#endif
+
/* Dynamic interrupt handling */
/**
diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c
index 3dc6a61bf06a..0a9104b4608b 100644
--- a/kernel/irq/manage.c
+++ b/kernel/irq/manage.c
@@ -382,14 +382,8 @@ setup_affinity(unsigned int irq, struct irq_desc *desc, struct cpumask *mask)
}
#endif
-void __disable_irq(struct irq_desc *desc, unsigned int irq, bool suspend)
+void __disable_irq(struct irq_desc *desc, unsigned int irq)
{
- if (suspend) {
- if (!desc->action || (desc->action->flags & IRQF_NO_SUSPEND))
- return;
- desc->istate |= IRQS_SUSPENDED;
- }
-
if (!desc->depth++)
irq_disable(desc);
}
@@ -401,7 +395,7 @@ static int __disable_irq_nosync(unsigned int irq)
if (!desc)
return -EINVAL;
- __disable_irq(desc, irq, false);
+ __disable_irq(desc, irq);
irq_put_desc_busunlock(desc, flags);
return 0;
}
@@ -442,20 +436,8 @@ void disable_irq(unsigned int irq)
}
EXPORT_SYMBOL(disable_irq);
-void __enable_irq(struct irq_desc *desc, unsigned int irq, bool resume)
+void __enable_irq(struct irq_desc *desc, unsigned int irq)
{
- if (resume) {
- if (!(desc->istate & IRQS_SUSPENDED)) {
- if (!desc->action)
- return;
- if (!(desc->action->flags & IRQF_FORCE_RESUME))
- return;
- /* Pretend that it got disabled ! */
- desc->depth++;
- }
- desc->istate &= ~IRQS_SUSPENDED;
- }
-
switch (desc->depth) {
case 0:
err_out:
@@ -497,7 +479,7 @@ void enable_irq(unsigned int irq)
KERN_ERR "enable_irq before setup/request_irq: irq %u\n", irq))
goto out;
- __enable_irq(desc, irq, false);
+ __enable_irq(desc, irq);
out:
irq_put_desc_busunlock(desc, flags);
}
@@ -1218,6 +1200,8 @@ __setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new)
new->irq = irq;
*old_ptr = new;
+ irq_pm_install_action(desc, new);
+
/* Reset broken irq detection when installing new handler */
desc->irq_count = 0;
desc->irqs_unhandled = 0;
@@ -1228,7 +1212,7 @@ __setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new)
*/
if (shared && (desc->istate & IRQS_SPURIOUS_DISABLED)) {
desc->istate &= ~IRQS_SPURIOUS_DISABLED;
- __enable_irq(desc, irq, false);
+ __enable_irq(desc, irq);
}
raw_spin_unlock_irqrestore(&desc->lock, flags);
@@ -1336,6 +1320,8 @@ static struct irqaction *__free_irq(unsigned int irq, void *dev_id)
/* Found it - now remove it from the list of entries: */
*action_ptr = action->next;
+ irq_pm_remove_action(desc, action);
+
/* If this was the last handler, shut down the IRQ line: */
if (!desc->action) {
irq_shutdown(desc);
diff --git a/kernel/irq/pm.c b/kernel/irq/pm.c
index abcd6ca86cb7..3ca532592704 100644
--- a/kernel/irq/pm.c
+++ b/kernel/irq/pm.c
@@ -9,17 +9,105 @@
#include <linux/irq.h>
#include <linux/module.h>
#include <linux/interrupt.h>
+#include <linux/suspend.h>
#include <linux/syscore_ops.h>
#include "internals.h"
+bool irq_pm_check_wakeup(struct irq_desc *desc)
+{
+ if (irqd_is_wakeup_armed(&desc->irq_data)) {
+ irqd_clear(&desc->irq_data, IRQD_WAKEUP_ARMED);
+ desc->istate |= IRQS_SUSPENDED | IRQS_PENDING;
+ desc->depth++;
+ irq_disable(desc);
+ pm_system_wakeup();
+ return true;
+ }
+ return false;
+}
+
+/*
+ * Called from __setup_irq() with desc->lock held after @action has
+ * been installed in the action chain.
+ */
+void irq_pm_install_action(struct irq_desc *desc, struct irqaction *action)
+{
+ desc->nr_actions++;
+
+ if (action->flags & IRQF_FORCE_RESUME)
+ desc->force_resume_depth++;
+
+ WARN_ON_ONCE(desc->force_resume_depth &&
+ desc->force_resume_depth != desc->nr_actions);
+
+ if (action->flags & IRQF_NO_SUSPEND)
+ desc->no_suspend_depth++;
+
+ WARN_ON_ONCE(desc->no_suspend_depth &&
+ desc->no_suspend_depth != desc->nr_actions);
+}
+
+/*
+ * Called from __free_irq() with desc->lock held after @action has
+ * been removed from the action chain.
+ */
+void irq_pm_remove_action(struct irq_desc *desc, struct irqaction *action)
+{
+ desc->nr_actions--;
+
+ if (action->flags & IRQF_FORCE_RESUME)
+ desc->force_resume_depth--;
+
+ if (action->flags & IRQF_NO_SUSPEND)
+ desc->no_suspend_depth--;
+}
+
+static bool suspend_device_irq(struct irq_desc *desc, int irq)
+{
+ if (!desc->action || desc->no_suspend_depth)
+ return false;
+
+ if (irqd_is_wakeup_set(&desc->irq_data)) {
+ irqd_set(&desc->irq_data, IRQD_WAKEUP_ARMED);
+ /*
+ * We return true here to force the caller to issue
+ * synchronize_irq(). We need to make sure that the
+ * IRQD_WAKEUP_ARMED is visible before we return from
+ * suspend_device_irqs().
+ */
+ return true;
+ }
+
+ desc->istate |= IRQS_SUSPENDED;
+ __disable_irq(desc, irq);
+
+ /*
+ * Hardware which has no wakeup source configuration facility
+ * requires that the non wakeup interrupts are masked at the
+ * chip level. The chip implementation indicates that with
+ * IRQCHIP_MASK_ON_SUSPEND.
+ */
+ if (irq_desc_get_chip(desc)->flags & IRQCHIP_MASK_ON_SUSPEND)
+ mask_irq(desc);
+ return true;
+}
+
/**
* suspend_device_irqs - disable all currently enabled interrupt lines
*
- * During system-wide suspend or hibernation device drivers need to be prevented
- * from receiving interrupts and this function is provided for this purpose.
- * It marks all interrupt lines in use, except for the timer ones, as disabled
- * and sets the IRQS_SUSPENDED flag for each of them.
+ * During system-wide suspend or hibernation device drivers need to be
+ * prevented from receiving interrupts and this function is provided
+ * for this purpose.
+ *
+ * So we disable all interrupts and mark them IRQS_SUSPENDED except
+ * for those which are unused, those which are marked as not
+ * suspendable via an interrupt request with the flag IRQF_NO_SUSPEND
+ * set and those which are marked as active wakeup sources.
+ *
+ * The active wakeup sources are handled by the flow handler entry
+ * code which checks for the IRQD_WAKEUP_ARMED flag, suspends the
+ * interrupt and notifies the pm core about the wakeup.
*/
void suspend_device_irqs(void)
{
@@ -28,18 +116,36 @@ void suspend_device_irqs(void)
for_each_irq_desc(irq, desc) {
unsigned long flags;
+ bool sync;
raw_spin_lock_irqsave(&desc->lock, flags);
- __disable_irq(desc, irq, true);
+ sync = suspend_device_irq(desc, irq);
raw_spin_unlock_irqrestore(&desc->lock, flags);
- }
- for_each_irq_desc(irq, desc)
- if (desc->istate & IRQS_SUSPENDED)
+ if (sync)
synchronize_irq(irq);
+ }
}
EXPORT_SYMBOL_GPL(suspend_device_irqs);
+static void resume_irq(struct irq_desc *desc, int irq)
+{
+ irqd_clear(&desc->irq_data, IRQD_WAKEUP_ARMED);
+
+ if (desc->istate & IRQS_SUSPENDED)
+ goto resume;
+
+ /* Force resume the interrupt? */
+ if (!desc->force_resume_depth)
+ return;
+
+ /* Pretend that it got disabled ! */
+ desc->depth++;
+resume:
+ desc->istate &= ~IRQS_SUSPENDED;
+ __enable_irq(desc, irq);
+}
+
static void resume_irqs(bool want_early)
{
struct irq_desc *desc;
@@ -54,7 +160,7 @@ static void resume_irqs(bool want_early)
continue;
raw_spin_lock_irqsave(&desc->lock, flags);
- __enable_irq(desc, irq, true);
+ resume_irq(desc, irq);
raw_spin_unlock_irqrestore(&desc->lock, flags);
}
}
@@ -93,38 +199,3 @@ void resume_device_irqs(void)
resume_irqs(false);
}
EXPORT_SYMBOL_GPL(resume_device_irqs);
-
-/**
- * check_wakeup_irqs - check if any wake-up interrupts are pending
- */
-int check_wakeup_irqs(void)
-{
- struct irq_desc *desc;
- int irq;
-
- for_each_irq_desc(irq, desc) {
- /*
- * Only interrupts which are marked as wakeup source
- * and have not been disabled before the suspend check
- * can abort suspend.
- */
- if (irqd_is_wakeup_set(&desc->irq_data)) {
- if (desc->depth == 1 && desc->istate & IRQS_PENDING)
- return -EBUSY;
- continue;
- }
- /*
- * Check the non wakeup interrupts whether they need
- * to be masked before finally going into suspend
- * state. That's for hardware which has no wakeup
- * source configuration facility. The chip
- * implementation indicates that with
- * IRQCHIP_MASK_ON_SUSPEND.
- */
- if (desc->istate & IRQS_SUSPENDED &&
- irq_desc_get_chip(desc)->flags & IRQCHIP_MASK_ON_SUSPEND)
- mask_irq(desc);
- }
-
- return 0;
-}
diff --git a/kernel/irq_work.c b/kernel/irq_work.c
index 345d19edcdae..3ab9048483fa 100644
--- a/kernel/irq_work.c
+++ b/kernel/irq_work.c
@@ -115,8 +115,10 @@ bool irq_work_needs_cpu(void)
raised = this_cpu_ptr(&raised_list);
lazy = this_cpu_ptr(&lazy_list);
- if (llist_empty(raised) && llist_empty(lazy))
- return false;
+
+ if (llist_empty(raised) || arch_irq_work_has_interrupt())
+ if (llist_empty(lazy))
+ return false;
/* All work should have been flushed before going offline */
WARN_ON_ONCE(cpu_is_offline(smp_processor_id()));
@@ -171,6 +173,15 @@ void irq_work_run(void)
}
EXPORT_SYMBOL_GPL(irq_work_run);
+void irq_work_tick(void)
+{
+ struct llist_head *raised = &__get_cpu_var(raised_list);
+
+ if (!llist_empty(raised) && !arch_irq_work_has_interrupt())
+ irq_work_run_list(raised);
+ irq_work_run_list(&__get_cpu_var(lazy_list));
+}
+
/*
* Synchronize against the irq_work @entry, ensures the entry is not
* currently in use.
diff --git a/kernel/kallsyms.c b/kernel/kallsyms.c
index ae5167087845..5c5987f10819 100644
--- a/kernel/kallsyms.c
+++ b/kernel/kallsyms.c
@@ -565,19 +565,12 @@ static int kallsyms_open(struct inode *inode, struct file *file)
* using get_symbol_offset for every symbol.
*/
struct kallsym_iter *iter;
- int ret;
-
- iter = kmalloc(sizeof(*iter), GFP_KERNEL);
+ iter = __seq_open_private(file, &kallsyms_op, sizeof(*iter));
if (!iter)
return -ENOMEM;
reset_iter(iter, 0);
- ret = seq_open(file, &kallsyms_op);
- if (ret == 0)
- ((struct seq_file *)file->private_data)->private = iter;
- else
- kfree(iter);
- return ret;
+ return 0;
}
#ifdef CONFIG_KGDB_KDB
diff --git a/kernel/kcmp.c b/kernel/kcmp.c
index e30ac0fe61c3..0aa69ea1d8fd 100644
--- a/kernel/kcmp.c
+++ b/kernel/kcmp.c
@@ -44,11 +44,12 @@ static long kptr_obfuscate(long v, int type)
*/
static int kcmp_ptr(void *v1, void *v2, enum kcmp_type type)
{
- long ret;
+ long t1, t2;
- ret = kptr_obfuscate((long)v1, type) - kptr_obfuscate((long)v2, type);
+ t1 = kptr_obfuscate((long)v1, type);
+ t2 = kptr_obfuscate((long)v2, type);
- return (ret < 0) | ((ret > 0) << 1);
+ return (t1 < t2) | ((t1 > t2) << 1);
}
/* The caller must have pinned the task */
diff --git a/kernel/kexec.c b/kernel/kexec.c
index 0b49a0a58102..2abf9f6e9a61 100644
--- a/kernel/kexec.c
+++ b/kernel/kexec.c
@@ -64,7 +64,9 @@ bool kexec_in_progress = false;
char __weak kexec_purgatory[0];
size_t __weak kexec_purgatory_size = 0;
+#ifdef CONFIG_KEXEC_FILE
static int kexec_calculate_store_digests(struct kimage *image);
+#endif
/* Location of the reserved area for the crash kernel */
struct resource crashk_res = {
@@ -341,6 +343,7 @@ out_free_image:
return ret;
}
+#ifdef CONFIG_KEXEC_FILE
static int copy_file_from_fd(int fd, void **buf, unsigned long *buf_len)
{
struct fd f = fdget(fd);
@@ -612,6 +615,9 @@ out_free_image:
kfree(image);
return ret;
}
+#else /* CONFIG_KEXEC_FILE */
+static inline void kimage_file_post_load_cleanup(struct kimage *image) { }
+#endif /* CONFIG_KEXEC_FILE */
static int kimage_is_destination_range(struct kimage *image,
unsigned long start,
@@ -1375,6 +1381,7 @@ COMPAT_SYSCALL_DEFINE4(kexec_load, compat_ulong_t, entry,
}
#endif
+#ifdef CONFIG_KEXEC_FILE
SYSCALL_DEFINE5(kexec_file_load, int, kernel_fd, int, initrd_fd,
unsigned long, cmdline_len, const char __user *, cmdline_ptr,
unsigned long, flags)
@@ -1451,6 +1458,8 @@ out:
return ret;
}
+#endif /* CONFIG_KEXEC_FILE */
+
void crash_kexec(struct pt_regs *regs)
{
/* Take the kexec_mutex here to prevent sys_kexec_load
@@ -1750,7 +1759,6 @@ static __initdata char *suffix_tbl[] = {
*/
static int __init parse_crashkernel_suffix(char *cmdline,
unsigned long long *crash_size,
- unsigned long long *crash_base,
const char *suffix)
{
char *cur = cmdline;
@@ -1839,7 +1847,7 @@ static int __init __parse_crashkernel(char *cmdline,
if (suffix)
return parse_crashkernel_suffix(ck_cmdline, crash_size,
- crash_base, suffix);
+ suffix);
/*
* if the commandline contains a ':', then that's the extended
* syntax -- if not, it must be the classic syntax
@@ -2006,22 +2014,7 @@ static int __init crash_save_vmcoreinfo_init(void)
subsys_initcall(crash_save_vmcoreinfo_init);
-static int __kexec_add_segment(struct kimage *image, char *buf,
- unsigned long bufsz, unsigned long mem,
- unsigned long memsz)
-{
- struct kexec_segment *ksegment;
-
- ksegment = &image->segment[image->nr_segments];
- ksegment->kbuf = buf;
- ksegment->bufsz = bufsz;
- ksegment->mem = mem;
- ksegment->memsz = memsz;
- image->nr_segments++;
-
- return 0;
-}
-
+#ifdef CONFIG_KEXEC_FILE
static int locate_mem_hole_top_down(unsigned long start, unsigned long end,
struct kexec_buf *kbuf)
{
@@ -2054,8 +2047,7 @@ static int locate_mem_hole_top_down(unsigned long start, unsigned long end,
} while (1);
/* If we are here, we found a suitable memory range */
- __kexec_add_segment(image, kbuf->buffer, kbuf->bufsz, temp_start,
- kbuf->memsz);
+ kbuf->mem = temp_start;
/* Success, stop navigating through remaining System RAM ranges */
return 1;
@@ -2089,8 +2081,7 @@ static int locate_mem_hole_bottom_up(unsigned long start, unsigned long end,
} while (1);
/* If we are here, we found a suitable memory range */
- __kexec_add_segment(image, kbuf->buffer, kbuf->bufsz, temp_start,
- kbuf->memsz);
+ kbuf->mem = temp_start;
/* Success, stop navigating through remaining System RAM ranges */
return 1;
@@ -2177,7 +2168,12 @@ int kexec_add_buffer(struct kimage *image, char *buffer, unsigned long bufsz,
}
/* Found a suitable memory range */
- ksegment = &image->segment[image->nr_segments - 1];
+ ksegment = &image->segment[image->nr_segments];
+ ksegment->kbuf = kbuf->buffer;
+ ksegment->bufsz = kbuf->bufsz;
+ ksegment->mem = kbuf->mem;
+ ksegment->memsz = kbuf->memsz;
+ image->nr_segments++;
*load_addr = ksegment->mem;
return 0;
}
@@ -2682,6 +2678,7 @@ int kexec_purgatory_get_set_symbol(struct kimage *image, const char *name,
return 0;
}
+#endif /* CONFIG_KEXEC_FILE */
/*
* Move into place and start executing a preloaded standalone
diff --git a/kernel/kprobes.c b/kernel/kprobes.c
index 734e9a7d280b..3995f546d0f3 100644
--- a/kernel/kprobes.c
+++ b/kernel/kprobes.c
@@ -1778,7 +1778,18 @@ static int pre_handler_kretprobe(struct kprobe *p, struct pt_regs *regs)
unsigned long hash, flags = 0;
struct kretprobe_instance *ri;
- /*TODO: consider to only swap the RA after the last pre_handler fired */
+ /*
+ * To avoid deadlocks, prohibit return probing in NMI contexts,
+ * just skip the probe and increase the (inexact) 'nmissed'
+ * statistical counter, so that the user is informed that
+ * something happened:
+ */
+ if (unlikely(in_nmi())) {
+ rp->nmissed++;
+ return 0;
+ }
+
+ /* TODO: consider to only swap the RA after the last pre_handler fired */
hash = hash_ptr(current, KPROBE_HASH_BITS);
raw_spin_lock_irqsave(&rp->lock, flags);
if (!hlist_empty(&rp->free_instances)) {
diff --git a/kernel/kthread.c b/kernel/kthread.c
index ef483220e855..10e489c448fe 100644
--- a/kernel/kthread.c
+++ b/kernel/kthread.c
@@ -369,7 +369,7 @@ struct task_struct *kthread_create_on_cpu(int (*threadfn)(void *data),
{
struct task_struct *p;
- p = kthread_create_on_node(threadfn, data, cpu_to_mem(cpu), namefmt,
+ p = kthread_create_on_node(threadfn, data, cpu_to_node(cpu), namefmt,
cpu);
if (IS_ERR(p))
return p;
diff --git a/kernel/locking/locktorture.c b/kernel/locking/locktorture.c
index 0955b885d0dc..ec8cce259779 100644
--- a/kernel/locking/locktorture.c
+++ b/kernel/locking/locktorture.c
@@ -20,30 +20,20 @@
* Author: Paul E. McKenney <paulmck@us.ibm.com>
* Based on kernel/rcu/torture.c.
*/
-#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/rwlock.h>
+#include <linux/mutex.h>
+#include <linux/rwsem.h>
#include <linux/smp.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/slab.h>
-#include <linux/trace_clock.h>
-#include <asm/byteorder.h>
#include <linux/torture.h>
MODULE_LICENSE("GPL");
@@ -51,6 +41,8 @@ MODULE_AUTHOR("Paul E. McKenney <paulmck@us.ibm.com>");
torture_param(int, nwriters_stress, -1,
"Number of write-locking stress-test threads");
+torture_param(int, nreaders_stress, -1,
+ "Number of read-locking stress-test threads");
torture_param(int, onoff_holdoff, 0, "Time after boot before CPU hotplugs (s)");
torture_param(int, onoff_interval, 0,
"Time between CPU hotplugs (s), 0=disable");
@@ -66,30 +58,28 @@ torture_param(bool, verbose, true,
static char *torture_type = "spin_lock";
module_param(torture_type, charp, 0444);
MODULE_PARM_DESC(torture_type,
- "Type of lock to torture (spin_lock, spin_lock_irq, ...)");
-
-static atomic_t n_lock_torture_errors;
+ "Type of lock to torture (spin_lock, spin_lock_irq, mutex_lock, ...)");
static struct task_struct *stats_task;
static struct task_struct **writer_tasks;
+static struct task_struct **reader_tasks;
-static int nrealwriters_stress;
static bool lock_is_write_held;
+static bool lock_is_read_held;
-struct lock_writer_stress_stats {
- long n_write_lock_fail;
- long n_write_lock_acquired;
+struct lock_stress_stats {
+ long n_lock_fail;
+ long n_lock_acquired;
};
-static struct lock_writer_stress_stats *lwsa;
#if defined(MODULE)
#define LOCKTORTURE_RUNNABLE_INIT 1
#else
#define LOCKTORTURE_RUNNABLE_INIT 0
#endif
-int locktorture_runnable = LOCKTORTURE_RUNNABLE_INIT;
-module_param(locktorture_runnable, int, 0444);
-MODULE_PARM_DESC(locktorture_runnable, "Start locktorture at module init");
+int torture_runnable = LOCKTORTURE_RUNNABLE_INIT;
+module_param(torture_runnable, int, 0444);
+MODULE_PARM_DESC(torture_runnable, "Start locktorture at module init");
/* Forward reference. */
static void lock_torture_cleanup(void);
@@ -102,12 +92,25 @@ struct lock_torture_ops {
int (*writelock)(void);
void (*write_delay)(struct torture_random_state *trsp);
void (*writeunlock)(void);
+ int (*readlock)(void);
+ void (*read_delay)(struct torture_random_state *trsp);
+ void (*readunlock)(void);
unsigned long flags;
const char *name;
};
-static struct lock_torture_ops *cur_ops;
-
+struct lock_torture_cxt {
+ int nrealwriters_stress;
+ int nrealreaders_stress;
+ bool debug_lock;
+ atomic_t n_lock_torture_errors;
+ struct lock_torture_ops *cur_ops;
+ struct lock_stress_stats *lwsa; /* writer statistics */
+ struct lock_stress_stats *lrsa; /* reader statistics */
+};
+static struct lock_torture_cxt cxt = { 0, 0, false,
+ ATOMIC_INIT(0),
+ NULL, NULL};
/*
* Definitions for lock torture testing.
*/
@@ -123,10 +126,10 @@ static void torture_lock_busted_write_delay(struct torture_random_state *trsp)
/* We want a long delay occasionally to force massive contention. */
if (!(torture_random(trsp) %
- (nrealwriters_stress * 2000 * longdelay_us)))
+ (cxt.nrealwriters_stress * 2000 * longdelay_us)))
mdelay(longdelay_us);
#ifdef CONFIG_PREEMPT
- if (!(torture_random(trsp) % (nrealwriters_stress * 20000)))
+ if (!(torture_random(trsp) % (cxt.nrealwriters_stress * 20000)))
preempt_schedule(); /* Allow test to be preempted. */
#endif
}
@@ -140,6 +143,9 @@ static struct lock_torture_ops lock_busted_ops = {
.writelock = torture_lock_busted_write_lock,
.write_delay = torture_lock_busted_write_delay,
.writeunlock = torture_lock_busted_write_unlock,
+ .readlock = NULL,
+ .read_delay = NULL,
+ .readunlock = NULL,
.name = "lock_busted"
};
@@ -160,13 +166,13 @@ static void torture_spin_lock_write_delay(struct torture_random_state *trsp)
* we want a long delay occasionally to force massive contention.
*/
if (!(torture_random(trsp) %
- (nrealwriters_stress * 2000 * longdelay_us)))
+ (cxt.nrealwriters_stress * 2000 * longdelay_us)))
mdelay(longdelay_us);
if (!(torture_random(trsp) %
- (nrealwriters_stress * 2 * shortdelay_us)))
+ (cxt.nrealwriters_stress * 2 * shortdelay_us)))
udelay(shortdelay_us);
#ifdef CONFIG_PREEMPT
- if (!(torture_random(trsp) % (nrealwriters_stress * 20000)))
+ if (!(torture_random(trsp) % (cxt.nrealwriters_stress * 20000)))
preempt_schedule(); /* Allow test to be preempted. */
#endif
}
@@ -180,39 +186,253 @@ static struct lock_torture_ops spin_lock_ops = {
.writelock = torture_spin_lock_write_lock,
.write_delay = torture_spin_lock_write_delay,
.writeunlock = torture_spin_lock_write_unlock,
+ .readlock = NULL,
+ .read_delay = NULL,
+ .readunlock = NULL,
.name = "spin_lock"
};
static int torture_spin_lock_write_lock_irq(void)
-__acquires(torture_spinlock_irq)
+__acquires(torture_spinlock)
{
unsigned long flags;
spin_lock_irqsave(&torture_spinlock, flags);
- cur_ops->flags = flags;
+ cxt.cur_ops->flags = flags;
return 0;
}
static void torture_lock_spin_write_unlock_irq(void)
__releases(torture_spinlock)
{
- spin_unlock_irqrestore(&torture_spinlock, cur_ops->flags);
+ spin_unlock_irqrestore(&torture_spinlock, cxt.cur_ops->flags);
}
static struct lock_torture_ops spin_lock_irq_ops = {
.writelock = torture_spin_lock_write_lock_irq,
.write_delay = torture_spin_lock_write_delay,
.writeunlock = torture_lock_spin_write_unlock_irq,
+ .readlock = NULL,
+ .read_delay = NULL,
+ .readunlock = NULL,
.name = "spin_lock_irq"
};
+static DEFINE_RWLOCK(torture_rwlock);
+
+static int torture_rwlock_write_lock(void) __acquires(torture_rwlock)
+{
+ write_lock(&torture_rwlock);
+ return 0;
+}
+
+static void torture_rwlock_write_delay(struct torture_random_state *trsp)
+{
+ const unsigned long shortdelay_us = 2;
+ const unsigned long longdelay_ms = 100;
+
+ /* We want a short delay mostly to emulate likely code, and
+ * we want a long delay occasionally to force massive contention.
+ */
+ if (!(torture_random(trsp) %
+ (cxt.nrealwriters_stress * 2000 * longdelay_ms)))
+ mdelay(longdelay_ms);
+ else
+ udelay(shortdelay_us);
+}
+
+static void torture_rwlock_write_unlock(void) __releases(torture_rwlock)
+{
+ write_unlock(&torture_rwlock);
+}
+
+static int torture_rwlock_read_lock(void) __acquires(torture_rwlock)
+{
+ read_lock(&torture_rwlock);
+ return 0;
+}
+
+static void torture_rwlock_read_delay(struct torture_random_state *trsp)
+{
+ const unsigned long shortdelay_us = 10;
+ const unsigned long longdelay_ms = 100;
+
+ /* We want a short delay mostly to emulate likely code, and
+ * we want a long delay occasionally to force massive contention.
+ */
+ if (!(torture_random(trsp) %
+ (cxt.nrealreaders_stress * 2000 * longdelay_ms)))
+ mdelay(longdelay_ms);
+ else
+ udelay(shortdelay_us);
+}
+
+static void torture_rwlock_read_unlock(void) __releases(torture_rwlock)
+{
+ read_unlock(&torture_rwlock);
+}
+
+static struct lock_torture_ops rw_lock_ops = {
+ .writelock = torture_rwlock_write_lock,
+ .write_delay = torture_rwlock_write_delay,
+ .writeunlock = torture_rwlock_write_unlock,
+ .readlock = torture_rwlock_read_lock,
+ .read_delay = torture_rwlock_read_delay,
+ .readunlock = torture_rwlock_read_unlock,
+ .name = "rw_lock"
+};
+
+static int torture_rwlock_write_lock_irq(void) __acquires(torture_rwlock)
+{
+ unsigned long flags;
+
+ write_lock_irqsave(&torture_rwlock, flags);
+ cxt.cur_ops->flags = flags;
+ return 0;
+}
+
+static void torture_rwlock_write_unlock_irq(void)
+__releases(torture_rwlock)
+{
+ write_unlock_irqrestore(&torture_rwlock, cxt.cur_ops->flags);
+}
+
+static int torture_rwlock_read_lock_irq(void) __acquires(torture_rwlock)
+{
+ unsigned long flags;
+
+ read_lock_irqsave(&torture_rwlock, flags);
+ cxt.cur_ops->flags = flags;
+ return 0;
+}
+
+static void torture_rwlock_read_unlock_irq(void)
+__releases(torture_rwlock)
+{
+ write_unlock_irqrestore(&torture_rwlock, cxt.cur_ops->flags);
+}
+
+static struct lock_torture_ops rw_lock_irq_ops = {
+ .writelock = torture_rwlock_write_lock_irq,
+ .write_delay = torture_rwlock_write_delay,
+ .writeunlock = torture_rwlock_write_unlock_irq,
+ .readlock = torture_rwlock_read_lock_irq,
+ .read_delay = torture_rwlock_read_delay,
+ .readunlock = torture_rwlock_read_unlock_irq,
+ .name = "rw_lock_irq"
+};
+
+static DEFINE_MUTEX(torture_mutex);
+
+static int torture_mutex_lock(void) __acquires(torture_mutex)
+{
+ mutex_lock(&torture_mutex);
+ return 0;
+}
+
+static void torture_mutex_delay(struct torture_random_state *trsp)
+{
+ const unsigned long longdelay_ms = 100;
+
+ /* We want a long delay occasionally to force massive contention. */
+ if (!(torture_random(trsp) %
+ (cxt.nrealwriters_stress * 2000 * longdelay_ms)))
+ mdelay(longdelay_ms * 5);
+ else
+ mdelay(longdelay_ms / 5);
+#ifdef CONFIG_PREEMPT
+ if (!(torture_random(trsp) % (cxt.nrealwriters_stress * 20000)))
+ preempt_schedule(); /* Allow test to be preempted. */
+#endif
+}
+
+static void torture_mutex_unlock(void) __releases(torture_mutex)
+{
+ mutex_unlock(&torture_mutex);
+}
+
+static struct lock_torture_ops mutex_lock_ops = {
+ .writelock = torture_mutex_lock,
+ .write_delay = torture_mutex_delay,
+ .writeunlock = torture_mutex_unlock,
+ .readlock = NULL,
+ .read_delay = NULL,
+ .readunlock = NULL,
+ .name = "mutex_lock"
+};
+
+static DECLARE_RWSEM(torture_rwsem);
+static int torture_rwsem_down_write(void) __acquires(torture_rwsem)
+{
+ down_write(&torture_rwsem);
+ return 0;
+}
+
+static void torture_rwsem_write_delay(struct torture_random_state *trsp)
+{
+ const unsigned long longdelay_ms = 100;
+
+ /* We want a long delay occasionally to force massive contention. */
+ if (!(torture_random(trsp) %
+ (cxt.nrealwriters_stress * 2000 * longdelay_ms)))
+ mdelay(longdelay_ms * 10);
+ else
+ mdelay(longdelay_ms / 10);
+#ifdef CONFIG_PREEMPT
+ if (!(torture_random(trsp) % (cxt.nrealwriters_stress * 20000)))
+ preempt_schedule(); /* Allow test to be preempted. */
+#endif
+}
+
+static void torture_rwsem_up_write(void) __releases(torture_rwsem)
+{
+ up_write(&torture_rwsem);
+}
+
+static int torture_rwsem_down_read(void) __acquires(torture_rwsem)
+{
+ down_read(&torture_rwsem);
+ return 0;
+}
+
+static void torture_rwsem_read_delay(struct torture_random_state *trsp)
+{
+ const unsigned long longdelay_ms = 100;
+
+ /* We want a long delay occasionally to force massive contention. */
+ if (!(torture_random(trsp) %
+ (cxt.nrealwriters_stress * 2000 * longdelay_ms)))
+ mdelay(longdelay_ms * 2);
+ else
+ mdelay(longdelay_ms / 2);
+#ifdef CONFIG_PREEMPT
+ if (!(torture_random(trsp) % (cxt.nrealreaders_stress * 20000)))
+ preempt_schedule(); /* Allow test to be preempted. */
+#endif
+}
+
+static void torture_rwsem_up_read(void) __releases(torture_rwsem)
+{
+ up_read(&torture_rwsem);
+}
+
+static struct lock_torture_ops rwsem_lock_ops = {
+ .writelock = torture_rwsem_down_write,
+ .write_delay = torture_rwsem_write_delay,
+ .writeunlock = torture_rwsem_up_write,
+ .readlock = torture_rwsem_down_read,
+ .read_delay = torture_rwsem_read_delay,
+ .readunlock = torture_rwsem_up_read,
+ .name = "rwsem_lock"
+};
+
/*
* Lock torture writer kthread. Repeatedly acquires and releases
* the lock, checking for duplicate acquisitions.
*/
static int lock_torture_writer(void *arg)
{
- struct lock_writer_stress_stats *lwsp = arg;
+ struct lock_stress_stats *lwsp = arg;
static DEFINE_TORTURE_RANDOM(rand);
VERBOSE_TOROUT_STRING("lock_torture_writer task started");
@@ -221,14 +441,19 @@ static int lock_torture_writer(void *arg)
do {
if ((torture_random(&rand) & 0xfffff) == 0)
schedule_timeout_uninterruptible(1);
- cur_ops->writelock();
+
+ cxt.cur_ops->writelock();
if (WARN_ON_ONCE(lock_is_write_held))
- lwsp->n_write_lock_fail++;
+ lwsp->n_lock_fail++;
lock_is_write_held = 1;
- lwsp->n_write_lock_acquired++;
- cur_ops->write_delay(&rand);
+ if (WARN_ON_ONCE(lock_is_read_held))
+ lwsp->n_lock_fail++; /* rare, but... */
+
+ lwsp->n_lock_acquired++;
+ cxt.cur_ops->write_delay(&rand);
lock_is_write_held = 0;
- cur_ops->writeunlock();
+ cxt.cur_ops->writeunlock();
+
stutter_wait("lock_torture_writer");
} while (!torture_must_stop());
torture_kthread_stopping("lock_torture_writer");
@@ -236,32 +461,66 @@ static int lock_torture_writer(void *arg)
}
/*
+ * Lock torture reader kthread. Repeatedly acquires and releases
+ * the reader lock.
+ */
+static int lock_torture_reader(void *arg)
+{
+ struct lock_stress_stats *lrsp = arg;
+ static DEFINE_TORTURE_RANDOM(rand);
+
+ VERBOSE_TOROUT_STRING("lock_torture_reader task started");
+ set_user_nice(current, MAX_NICE);
+
+ do {
+ if ((torture_random(&rand) & 0xfffff) == 0)
+ schedule_timeout_uninterruptible(1);
+
+ cxt.cur_ops->readlock();
+ lock_is_read_held = 1;
+ if (WARN_ON_ONCE(lock_is_write_held))
+ lrsp->n_lock_fail++; /* rare, but... */
+
+ lrsp->n_lock_acquired++;
+ cxt.cur_ops->read_delay(&rand);
+ lock_is_read_held = 0;
+ cxt.cur_ops->readunlock();
+
+ stutter_wait("lock_torture_reader");
+ } while (!torture_must_stop());
+ torture_kthread_stopping("lock_torture_reader");
+ return 0;
+}
+
+/*
* Create an lock-torture-statistics message in the specified buffer.
*/
-static void lock_torture_printk(char *page)
+static void __torture_print_stats(char *page,
+ struct lock_stress_stats *statp, bool write)
{
bool fail = 0;
- int i;
+ int i, n_stress;
long max = 0;
- long min = lwsa[0].n_write_lock_acquired;
+ long min = statp[0].n_lock_acquired;
long long sum = 0;
- for (i = 0; i < nrealwriters_stress; i++) {
- if (lwsa[i].n_write_lock_fail)
+ n_stress = write ? cxt.nrealwriters_stress : cxt.nrealreaders_stress;
+ for (i = 0; i < n_stress; i++) {
+ if (statp[i].n_lock_fail)
fail = true;
- sum += lwsa[i].n_write_lock_acquired;
- if (max < lwsa[i].n_write_lock_fail)
- max = lwsa[i].n_write_lock_fail;
- if (min > lwsa[i].n_write_lock_fail)
- min = lwsa[i].n_write_lock_fail;
+ sum += statp[i].n_lock_acquired;
+ if (max < statp[i].n_lock_fail)
+ max = statp[i].n_lock_fail;
+ if (min > statp[i].n_lock_fail)
+ min = statp[i].n_lock_fail;
}
- page += sprintf(page, "%s%s ", torture_type, TORTURE_FLAG);
page += sprintf(page,
- "Writes: Total: %lld Max/Min: %ld/%ld %s Fail: %d %s\n",
+ "%s: Total: %lld Max/Min: %ld/%ld %s Fail: %d %s\n",
+ write ? "Writes" : "Reads ",
sum, max, min, max / 2 > min ? "???" : "",
fail, fail ? "!!!" : "");
if (fail)
- atomic_inc(&n_lock_torture_errors);
+ atomic_inc(&cxt.n_lock_torture_errors);
}
/*
@@ -274,18 +533,35 @@ static void lock_torture_printk(char *page)
*/
static void lock_torture_stats_print(void)
{
- int size = nrealwriters_stress * 200 + 8192;
+ int size = cxt.nrealwriters_stress * 200 + 8192;
char *buf;
+ if (cxt.cur_ops->readlock)
+ size += cxt.nrealreaders_stress * 200 + 8192;
+
buf = kmalloc(size, GFP_KERNEL);
if (!buf) {
pr_err("lock_torture_stats_print: Out of memory, need: %d",
size);
return;
}
- lock_torture_printk(buf);
+
+ __torture_print_stats(buf, cxt.lwsa, true);
pr_alert("%s", buf);
kfree(buf);
+
+ if (cxt.cur_ops->readlock) {
+ buf = kmalloc(size, GFP_KERNEL);
+ if (!buf) {
+ pr_err("lock_torture_stats_print: Out of memory, need: %d",
+ size);
+ return;
+ }
+
+ __torture_print_stats(buf, cxt.lrsa, false);
+ pr_alert("%s", buf);
+ kfree(buf);
+ }
}
/*
@@ -312,9 +588,10 @@ lock_torture_print_module_parms(struct lock_torture_ops *cur_ops,
const char *tag)
{
pr_alert("%s" TORTURE_FLAG
- "--- %s: nwriters_stress=%d stat_interval=%d verbose=%d shuffle_interval=%d stutter=%d shutdown_secs=%d onoff_interval=%d onoff_holdoff=%d\n",
- torture_type, tag, nrealwriters_stress, stat_interval, verbose,
- shuffle_interval, stutter, shutdown_secs,
+ "--- %s%s: nwriters_stress=%d nreaders_stress=%d stat_interval=%d verbose=%d shuffle_interval=%d stutter=%d shutdown_secs=%d onoff_interval=%d onoff_holdoff=%d\n",
+ torture_type, tag, cxt.debug_lock ? " [debug]": "",
+ cxt.nrealwriters_stress, cxt.nrealreaders_stress, stat_interval,
+ verbose, shuffle_interval, stutter, shutdown_secs,
onoff_interval, onoff_holdoff);
}
@@ -322,46 +599,59 @@ static void lock_torture_cleanup(void)
{
int i;
- if (torture_cleanup())
+ if (torture_cleanup_begin())
return;
if (writer_tasks) {
- for (i = 0; i < nrealwriters_stress; i++)
+ for (i = 0; i < cxt.nrealwriters_stress; i++)
torture_stop_kthread(lock_torture_writer,
writer_tasks[i]);
kfree(writer_tasks);
writer_tasks = NULL;
}
+ if (reader_tasks) {
+ for (i = 0; i < cxt.nrealreaders_stress; i++)
+ torture_stop_kthread(lock_torture_reader,
+ reader_tasks[i]);
+ kfree(reader_tasks);
+ reader_tasks = NULL;
+ }
+
torture_stop_kthread(lock_torture_stats, stats_task);
lock_torture_stats_print(); /* -After- the stats thread is stopped! */
- if (atomic_read(&n_lock_torture_errors))
- lock_torture_print_module_parms(cur_ops,
+ if (atomic_read(&cxt.n_lock_torture_errors))
+ lock_torture_print_module_parms(cxt.cur_ops,
"End of test: FAILURE");
else if (torture_onoff_failures())
- lock_torture_print_module_parms(cur_ops,
+ lock_torture_print_module_parms(cxt.cur_ops,
"End of test: LOCK_HOTPLUG");
else
- lock_torture_print_module_parms(cur_ops,
+ lock_torture_print_module_parms(cxt.cur_ops,
"End of test: SUCCESS");
+ torture_cleanup_end();
}
static int __init lock_torture_init(void)
{
- int i;
+ int i, j;
int firsterr = 0;
static struct lock_torture_ops *torture_ops[] = {
- &lock_busted_ops, &spin_lock_ops, &spin_lock_irq_ops,
+ &lock_busted_ops,
+ &spin_lock_ops, &spin_lock_irq_ops,
+ &rw_lock_ops, &rw_lock_irq_ops,
+ &mutex_lock_ops,
+ &rwsem_lock_ops,
};
- if (!torture_init_begin(torture_type, verbose, &locktorture_runnable))
+ if (!torture_init_begin(torture_type, verbose, &torture_runnable))
return -EBUSY;
/* Process args and tell the world that the torturer is on the job. */
for (i = 0; i < ARRAY_SIZE(torture_ops); i++) {
- cur_ops = torture_ops[i];
- if (strcmp(torture_type, cur_ops->name) == 0)
+ cxt.cur_ops = torture_ops[i];
+ if (strcmp(torture_type, cxt.cur_ops->name) == 0)
break;
}
if (i == ARRAY_SIZE(torture_ops)) {
@@ -374,31 +664,69 @@ static int __init lock_torture_init(void)
torture_init_end();
return -EINVAL;
}
- if (cur_ops->init)
- cur_ops->init(); /* no "goto unwind" prior to this point!!! */
+ if (cxt.cur_ops->init)
+ cxt.cur_ops->init(); /* no "goto unwind" prior to this point!!! */
if (nwriters_stress >= 0)
- nrealwriters_stress = nwriters_stress;
+ cxt.nrealwriters_stress = nwriters_stress;
else
- nrealwriters_stress = 2 * num_online_cpus();
- lock_torture_print_module_parms(cur_ops, "Start of test");
+ cxt.nrealwriters_stress = 2 * num_online_cpus();
+
+#ifdef CONFIG_DEBUG_MUTEXES
+ if (strncmp(torture_type, "mutex", 5) == 0)
+ cxt.debug_lock = true;
+#endif
+#ifdef CONFIG_DEBUG_SPINLOCK
+ if ((strncmp(torture_type, "spin", 4) == 0) ||
+ (strncmp(torture_type, "rw_lock", 7) == 0))
+ cxt.debug_lock = true;
+#endif
/* Initialize the statistics so that each run gets its own numbers. */
lock_is_write_held = 0;
- lwsa = kmalloc(sizeof(*lwsa) * nrealwriters_stress, GFP_KERNEL);
- if (lwsa == NULL) {
- VERBOSE_TOROUT_STRING("lwsa: Out of memory");
+ cxt.lwsa = kmalloc(sizeof(*cxt.lwsa) * cxt.nrealwriters_stress, GFP_KERNEL);
+ if (cxt.lwsa == NULL) {
+ VERBOSE_TOROUT_STRING("cxt.lwsa: Out of memory");
firsterr = -ENOMEM;
goto unwind;
}
- for (i = 0; i < nrealwriters_stress; i++) {
- lwsa[i].n_write_lock_fail = 0;
- lwsa[i].n_write_lock_acquired = 0;
+ for (i = 0; i < cxt.nrealwriters_stress; i++) {
+ cxt.lwsa[i].n_lock_fail = 0;
+ cxt.lwsa[i].n_lock_acquired = 0;
}
- /* Start up the kthreads. */
+ if (cxt.cur_ops->readlock) {
+ if (nreaders_stress >= 0)
+ cxt.nrealreaders_stress = nreaders_stress;
+ else {
+ /*
+ * By default distribute evenly the number of
+ * readers and writers. We still run the same number
+ * of threads as the writer-only locks default.
+ */
+ if (nwriters_stress < 0) /* user doesn't care */
+ cxt.nrealwriters_stress = num_online_cpus();
+ cxt.nrealreaders_stress = cxt.nrealwriters_stress;
+ }
+
+ lock_is_read_held = 0;
+ cxt.lrsa = kmalloc(sizeof(*cxt.lrsa) * cxt.nrealreaders_stress, GFP_KERNEL);
+ if (cxt.lrsa == NULL) {
+ VERBOSE_TOROUT_STRING("cxt.lrsa: Out of memory");
+ firsterr = -ENOMEM;
+ kfree(cxt.lwsa);
+ goto unwind;
+ }
+
+ for (i = 0; i < cxt.nrealreaders_stress; i++) {
+ cxt.lrsa[i].n_lock_fail = 0;
+ cxt.lrsa[i].n_lock_acquired = 0;
+ }
+ }
+ lock_torture_print_module_parms(cxt.cur_ops, "Start of test");
+ /* Prepare torture context. */
if (onoff_interval > 0) {
firsterr = torture_onoff_init(onoff_holdoff * HZ,
onoff_interval * HZ);
@@ -422,18 +750,51 @@ static int __init lock_torture_init(void)
goto unwind;
}
- writer_tasks = kzalloc(nrealwriters_stress * sizeof(writer_tasks[0]),
+ writer_tasks = kzalloc(cxt.nrealwriters_stress * sizeof(writer_tasks[0]),
GFP_KERNEL);
if (writer_tasks == NULL) {
VERBOSE_TOROUT_ERRSTRING("writer_tasks: Out of memory");
firsterr = -ENOMEM;
goto unwind;
}
- for (i = 0; i < nrealwriters_stress; i++) {
- firsterr = torture_create_kthread(lock_torture_writer, &lwsa[i],
+
+ if (cxt.cur_ops->readlock) {
+ reader_tasks = kzalloc(cxt.nrealreaders_stress * sizeof(reader_tasks[0]),
+ GFP_KERNEL);
+ if (reader_tasks == NULL) {
+ VERBOSE_TOROUT_ERRSTRING("reader_tasks: Out of memory");
+ firsterr = -ENOMEM;
+ goto unwind;
+ }
+ }
+
+ /*
+ * Create the kthreads and start torturing (oh, those poor little locks).
+ *
+ * TODO: Note that we interleave writers with readers, giving writers a
+ * slight advantage, by creating its kthread first. This can be modified
+ * for very specific needs, or even let the user choose the policy, if
+ * ever wanted.
+ */
+ for (i = 0, j = 0; i < cxt.nrealwriters_stress ||
+ j < cxt.nrealreaders_stress; i++, j++) {
+ if (i >= cxt.nrealwriters_stress)
+ goto create_reader;
+
+ /* Create writer. */
+ firsterr = torture_create_kthread(lock_torture_writer, &cxt.lwsa[i],
writer_tasks[i]);
if (firsterr)
goto unwind;
+
+ create_reader:
+ if (cxt.cur_ops->readlock == NULL || (j >= cxt.nrealreaders_stress))
+ continue;
+ /* Create reader. */
+ firsterr = torture_create_kthread(lock_torture_reader, &cxt.lrsa[j],
+ reader_tasks[j]);
+ if (firsterr)
+ goto unwind;
}
if (stat_interval > 0) {
firsterr = torture_create_kthread(lock_torture_stats, NULL,
diff --git a/kernel/locking/mcs_spinlock.h b/kernel/locking/mcs_spinlock.h
index 23e89c5930e9..4d60986fcbee 100644
--- a/kernel/locking/mcs_spinlock.h
+++ b/kernel/locking/mcs_spinlock.h
@@ -56,9 +56,6 @@ do { \
* If the lock has already been acquired, then this will proceed to spin
* on this node->locked until the previous lock holder sets the node->locked
* in mcs_spin_unlock().
- *
- * We don't inline mcs_spin_lock() so that perf can correctly account for the
- * time spent in this lock function.
*/
static inline
void mcs_spin_lock(struct mcs_spinlock **lock, struct mcs_spinlock *node)
diff --git a/kernel/locking/mutex.c b/kernel/locking/mutex.c
index ae712b25e492..dadbf88c22c4 100644
--- a/kernel/locking/mutex.c
+++ b/kernel/locking/mutex.c
@@ -15,7 +15,7 @@
* by Steven Rostedt, based on work by Gregory Haskins, Peter Morreale
* and Sven Dietrich.
*
- * Also see Documentation/mutex-design.txt.
+ * Also see Documentation/locking/mutex-design.txt.
*/
#include <linux/mutex.h>
#include <linux/ww_mutex.h>
@@ -106,6 +106,92 @@ void __sched mutex_lock(struct mutex *lock)
EXPORT_SYMBOL(mutex_lock);
#endif
+static __always_inline void ww_mutex_lock_acquired(struct ww_mutex *ww,
+ struct ww_acquire_ctx *ww_ctx)
+{
+#ifdef CONFIG_DEBUG_MUTEXES
+ /*
+ * If this WARN_ON triggers, you used ww_mutex_lock to acquire,
+ * but released with a normal mutex_unlock in this call.
+ *
+ * This should never happen, always use ww_mutex_unlock.
+ */
+ DEBUG_LOCKS_WARN_ON(ww->ctx);
+
+ /*
+ * Not quite done after calling ww_acquire_done() ?
+ */
+ DEBUG_LOCKS_WARN_ON(ww_ctx->done_acquire);
+
+ if (ww_ctx->contending_lock) {
+ /*
+ * After -EDEADLK you tried to
+ * acquire a different ww_mutex? Bad!
+ */
+ DEBUG_LOCKS_WARN_ON(ww_ctx->contending_lock != ww);
+
+ /*
+ * You called ww_mutex_lock after receiving -EDEADLK,
+ * but 'forgot' to unlock everything else first?
+ */
+ DEBUG_LOCKS_WARN_ON(ww_ctx->acquired > 0);
+ ww_ctx->contending_lock = NULL;
+ }
+
+ /*
+ * Naughty, using a different class will lead to undefined behavior!
+ */
+ DEBUG_LOCKS_WARN_ON(ww_ctx->ww_class != ww->ww_class);
+#endif
+ ww_ctx->acquired++;
+}
+
+/*
+ * after acquiring lock with fastpath or when we lost out in contested
+ * slowpath, set ctx and wake up any waiters so they can recheck.
+ *
+ * This function is never called when CONFIG_DEBUG_LOCK_ALLOC is set,
+ * as the fastpath and opportunistic spinning are disabled in that case.
+ */
+static __always_inline void
+ww_mutex_set_context_fastpath(struct ww_mutex *lock,
+ struct ww_acquire_ctx *ctx)
+{
+ unsigned long flags;
+ struct mutex_waiter *cur;
+
+ ww_mutex_lock_acquired(lock, ctx);
+
+ lock->ctx = ctx;
+
+ /*
+ * The lock->ctx update should be visible on all cores before
+ * the atomic read is done, otherwise contended waiters might be
+ * missed. The contended waiters will either see ww_ctx == NULL
+ * and keep spinning, or it will acquire wait_lock, add itself
+ * to waiter list and sleep.
+ */
+ smp_mb(); /* ^^^ */
+
+ /*
+ * Check if lock is contended, if not there is nobody to wake up
+ */
+ if (likely(atomic_read(&lock->base.count) == 0))
+ return;
+
+ /*
+ * Uh oh, we raced in fastpath, wake up everyone in this case,
+ * so they can see the new lock->ctx.
+ */
+ spin_lock_mutex(&lock->base.wait_lock, flags);
+ list_for_each_entry(cur, &lock->base.wait_list, list) {
+ debug_mutex_wake_waiter(&lock->base, cur);
+ wake_up_process(cur->task);
+ }
+ spin_unlock_mutex(&lock->base.wait_lock, flags);
+}
+
+
#ifdef CONFIG_MUTEX_SPIN_ON_OWNER
/*
* In order to avoid a stampede of mutex spinners from acquiring the mutex
@@ -180,6 +266,129 @@ static inline int mutex_can_spin_on_owner(struct mutex *lock)
*/
return retval;
}
+
+/*
+ * Atomically try to take the lock when it is available
+ */
+static inline bool mutex_try_to_acquire(struct mutex *lock)
+{
+ return !mutex_is_locked(lock) &&
+ (atomic_cmpxchg(&lock->count, 1, 0) == 1);
+}
+
+/*
+ * Optimistic spinning.
+ *
+ * We try to spin for acquisition when we find that the lock owner
+ * is currently running on a (different) CPU and while we don't
+ * need to reschedule. The rationale is that if the lock owner is
+ * running, it is likely to release the lock soon.
+ *
+ * Since this needs the lock owner, and this mutex implementation
+ * doesn't track the owner atomically in the lock field, we need to
+ * track it non-atomically.
+ *
+ * We can't do this for DEBUG_MUTEXES because that relies on wait_lock
+ * to serialize everything.
+ *
+ * The mutex spinners are queued up using MCS lock so that only one
+ * spinner can compete for the mutex. However, if mutex spinning isn't
+ * going to happen, there is no point in going through the lock/unlock
+ * overhead.
+ *
+ * Returns true when the lock was taken, otherwise false, indicating
+ * that we need to jump to the slowpath and sleep.
+ */
+static bool mutex_optimistic_spin(struct mutex *lock,
+ struct ww_acquire_ctx *ww_ctx, const bool use_ww_ctx)
+{
+ struct task_struct *task = current;
+
+ if (!mutex_can_spin_on_owner(lock))
+ goto done;
+
+ if (!osq_lock(&lock->osq))
+ goto done;
+
+ while (true) {
+ struct task_struct *owner;
+
+ if (use_ww_ctx && ww_ctx->acquired > 0) {
+ struct ww_mutex *ww;
+
+ ww = container_of(lock, struct ww_mutex, base);
+ /*
+ * If ww->ctx is set the contents are undefined, only
+ * by acquiring wait_lock there is a guarantee that
+ * they are not invalid when reading.
+ *
+ * As such, when deadlock detection needs to be
+ * performed the optimistic spinning cannot be done.
+ */
+ if (ACCESS_ONCE(ww->ctx))
+ break;
+ }
+
+ /*
+ * If there's an owner, wait for it to either
+ * release the lock or go to sleep.
+ */
+ owner = ACCESS_ONCE(lock->owner);
+ if (owner && !mutex_spin_on_owner(lock, owner))
+ break;
+
+ /* Try to acquire the mutex if it is unlocked. */
+ if (mutex_try_to_acquire(lock)) {
+ lock_acquired(&lock->dep_map, ip);
+
+ if (use_ww_ctx) {
+ struct ww_mutex *ww;
+ ww = container_of(lock, struct ww_mutex, base);
+
+ ww_mutex_set_context_fastpath(ww, ww_ctx);
+ }
+
+ mutex_set_owner(lock);
+ osq_unlock(&lock->osq);
+ return true;
+ }
+
+ /*
+ * When there's no owner, we might have preempted between the
+ * owner acquiring the lock and setting the owner field. If
+ * we're an RT task that will live-lock because we won't let
+ * the owner complete.
+ */
+ if (!owner && (need_resched() || rt_task(task)))
+ break;
+
+ /*
+ * The cpu_relax() call is a compiler barrier which forces
+ * everything in this loop to be re-loaded. We don't need
+ * memory barriers as we'll eventually observe the right
+ * values at the cost of a few extra spins.
+ */
+ cpu_relax_lowlatency();
+ }
+
+ osq_unlock(&lock->osq);
+done:
+ /*
+ * If we fell out of the spin path because of need_resched(),
+ * reschedule now, before we try-lock the mutex. This avoids getting
+ * scheduled out right after we obtained the mutex.
+ */
+ if (need_resched())
+ schedule_preempt_disabled();
+
+ return false;
+}
+#else
+static bool mutex_optimistic_spin(struct mutex *lock,
+ struct ww_acquire_ctx *ww_ctx, const bool use_ww_ctx)
+{
+ return false;
+}
#endif
__visible __used noinline
@@ -277,91 +486,6 @@ __mutex_lock_check_stamp(struct mutex *lock, struct ww_acquire_ctx *ctx)
return 0;
}
-static __always_inline void ww_mutex_lock_acquired(struct ww_mutex *ww,
- struct ww_acquire_ctx *ww_ctx)
-{
-#ifdef CONFIG_DEBUG_MUTEXES
- /*
- * If this WARN_ON triggers, you used ww_mutex_lock to acquire,
- * but released with a normal mutex_unlock in this call.
- *
- * This should never happen, always use ww_mutex_unlock.
- */
- DEBUG_LOCKS_WARN_ON(ww->ctx);
-
- /*
- * Not quite done after calling ww_acquire_done() ?
- */
- DEBUG_LOCKS_WARN_ON(ww_ctx->done_acquire);
-
- if (ww_ctx->contending_lock) {
- /*
- * After -EDEADLK you tried to
- * acquire a different ww_mutex? Bad!
- */
- DEBUG_LOCKS_WARN_ON(ww_ctx->contending_lock != ww);
-
- /*
- * You called ww_mutex_lock after receiving -EDEADLK,
- * but 'forgot' to unlock everything else first?
- */
- DEBUG_LOCKS_WARN_ON(ww_ctx->acquired > 0);
- ww_ctx->contending_lock = NULL;
- }
-
- /*
- * Naughty, using a different class will lead to undefined behavior!
- */
- DEBUG_LOCKS_WARN_ON(ww_ctx->ww_class != ww->ww_class);
-#endif
- ww_ctx->acquired++;
-}
-
-/*
- * after acquiring lock with fastpath or when we lost out in contested
- * slowpath, set ctx and wake up any waiters so they can recheck.
- *
- * This function is never called when CONFIG_DEBUG_LOCK_ALLOC is set,
- * as the fastpath and opportunistic spinning are disabled in that case.
- */
-static __always_inline void
-ww_mutex_set_context_fastpath(struct ww_mutex *lock,
- struct ww_acquire_ctx *ctx)
-{
- unsigned long flags;
- struct mutex_waiter *cur;
-
- ww_mutex_lock_acquired(lock, ctx);
-
- lock->ctx = ctx;
-
- /*
- * The lock->ctx update should be visible on all cores before
- * the atomic read is done, otherwise contended waiters might be
- * missed. The contended waiters will either see ww_ctx == NULL
- * and keep spinning, or it will acquire wait_lock, add itself
- * to waiter list and sleep.
- */
- smp_mb(); /* ^^^ */
-
- /*
- * Check if lock is contended, if not there is nobody to wake up
- */
- if (likely(atomic_read(&lock->base.count) == 0))
- return;
-
- /*
- * Uh oh, we raced in fastpath, wake up everyone in this case,
- * so they can see the new lock->ctx.
- */
- spin_lock_mutex(&lock->base.wait_lock, flags);
- list_for_each_entry(cur, &lock->base.wait_list, list) {
- debug_mutex_wake_waiter(&lock->base, cur);
- wake_up_process(cur->task);
- }
- spin_unlock_mutex(&lock->base.wait_lock, flags);
-}
-
/*
* Lock a mutex (possibly interruptible), slowpath:
*/
@@ -378,104 +502,12 @@ __mutex_lock_common(struct mutex *lock, long state, unsigned int subclass,
preempt_disable();
mutex_acquire_nest(&lock->dep_map, subclass, 0, nest_lock, ip);
-#ifdef CONFIG_MUTEX_SPIN_ON_OWNER
- /*
- * Optimistic spinning.
- *
- * We try to spin for acquisition when we find that the lock owner
- * is currently running on a (different) CPU and while we don't
- * need to reschedule. The rationale is that if the lock owner is
- * running, it is likely to release the lock soon.
- *
- * Since this needs the lock owner, and this mutex implementation
- * doesn't track the owner atomically in the lock field, we need to
- * track it non-atomically.
- *
- * We can't do this for DEBUG_MUTEXES because that relies on wait_lock
- * to serialize everything.
- *
- * The mutex spinners are queued up using MCS lock so that only one
- * spinner can compete for the mutex. However, if mutex spinning isn't
- * going to happen, there is no point in going through the lock/unlock
- * overhead.
- */
- if (!mutex_can_spin_on_owner(lock))
- goto slowpath;
-
- if (!osq_lock(&lock->osq))
- goto slowpath;
-
- for (;;) {
- struct task_struct *owner;
-
- if (use_ww_ctx && ww_ctx->acquired > 0) {
- struct ww_mutex *ww;
-
- ww = container_of(lock, struct ww_mutex, base);
- /*
- * If ww->ctx is set the contents are undefined, only
- * by acquiring wait_lock there is a guarantee that
- * they are not invalid when reading.
- *
- * As such, when deadlock detection needs to be
- * performed the optimistic spinning cannot be done.
- */
- if (ACCESS_ONCE(ww->ctx))
- break;
- }
-
- /*
- * If there's an owner, wait for it to either
- * release the lock or go to sleep.
- */
- owner = ACCESS_ONCE(lock->owner);
- if (owner && !mutex_spin_on_owner(lock, owner))
- break;
-
- /* Try to acquire the mutex if it is unlocked. */
- if (!mutex_is_locked(lock) &&
- (atomic_cmpxchg(&lock->count, 1, 0) == 1)) {
- lock_acquired(&lock->dep_map, ip);
- if (use_ww_ctx) {
- struct ww_mutex *ww;
- ww = container_of(lock, struct ww_mutex, base);
-
- ww_mutex_set_context_fastpath(ww, ww_ctx);
- }
-
- mutex_set_owner(lock);
- osq_unlock(&lock->osq);
- preempt_enable();
- return 0;
- }
-
- /*
- * When there's no owner, we might have preempted between the
- * owner acquiring the lock and setting the owner field. If
- * we're an RT task that will live-lock because we won't let
- * the owner complete.
- */
- if (!owner && (need_resched() || rt_task(task)))
- break;
-
- /*
- * The cpu_relax() call is a compiler barrier which forces
- * everything in this loop to be re-loaded. We don't need
- * memory barriers as we'll eventually observe the right
- * values at the cost of a few extra spins.
- */
- cpu_relax_lowlatency();
+ if (mutex_optimistic_spin(lock, ww_ctx, use_ww_ctx)) {
+ /* got the lock, yay! */
+ preempt_enable();
+ return 0;
}
- osq_unlock(&lock->osq);
-slowpath:
- /*
- * If we fell out of the spin path because of need_resched(),
- * reschedule now, before we try-lock the mutex. This avoids getting
- * scheduled out right after we obtained the mutex.
- */
- if (need_resched())
- schedule_preempt_disabled();
-#endif
+
spin_lock_mutex(&lock->wait_lock, flags);
/*
@@ -679,15 +711,21 @@ EXPORT_SYMBOL_GPL(__ww_mutex_lock_interruptible);
* Release the lock, slowpath:
*/
static inline void
-__mutex_unlock_common_slowpath(atomic_t *lock_count, int nested)
+__mutex_unlock_common_slowpath(struct mutex *lock, int nested)
{
- struct mutex *lock = container_of(lock_count, struct mutex, count);
unsigned long flags;
/*
- * some architectures leave the lock unlocked in the fastpath failure
+ * As a performance measurement, release the lock before doing other
+ * wakeup related duties to follow. This allows other tasks to acquire
+ * the lock sooner, while still handling cleanups in past unlock calls.
+ * This can be done as we do not enforce strict equivalence between the
+ * mutex counter and wait_list.
+ *
+ *
+ * Some architectures leave the lock unlocked in the fastpath failure
* case, others need to leave it locked. In the later case we have to
- * unlock it here
+ * unlock it here - as the lock counter is currently 0 or negative.
*/
if (__mutex_slowpath_needs_to_unlock())
atomic_set(&lock->count, 1);
@@ -716,7 +754,9 @@ __mutex_unlock_common_slowpath(atomic_t *lock_count, int nested)
__visible void
__mutex_unlock_slowpath(atomic_t *lock_count)
{
- __mutex_unlock_common_slowpath(lock_count, 1);
+ struct mutex *lock = container_of(lock_count, struct mutex, count);
+
+ __mutex_unlock_common_slowpath(lock, 1);
}
#ifndef CONFIG_DEBUG_LOCK_ALLOC
diff --git a/kernel/locking/mutex.h b/kernel/locking/mutex.h
index 4115fbf83b12..5cda397607f2 100644
--- a/kernel/locking/mutex.h
+++ b/kernel/locking/mutex.h
@@ -16,7 +16,7 @@
#define mutex_remove_waiter(lock, waiter, ti) \
__list_del((waiter)->list.prev, (waiter)->list.next)
-#ifdef CONFIG_SMP
+#ifdef CONFIG_MUTEX_SPIN_ON_OWNER
static inline void mutex_set_owner(struct mutex *lock)
{
lock->owner = current;
diff --git a/kernel/locking/rtmutex.c b/kernel/locking/rtmutex.c
index a0ea2a141b3b..7c98873a3077 100644
--- a/kernel/locking/rtmutex.c
+++ b/kernel/locking/rtmutex.c
@@ -8,7 +8,7 @@
* Copyright (C) 2005 Kihon Technologies Inc., Steven Rostedt
* Copyright (C) 2006 Esben Nielsen
*
- * See Documentation/rt-mutex-design.txt for details.
+ * See Documentation/locking/rt-mutex-design.txt for details.
*/
#include <linux/spinlock.h>
#include <linux/export.h>
diff --git a/kernel/locking/rwsem-xadd.c b/kernel/locking/rwsem-xadd.c
index d6203faf2eb1..7628c3fc37ca 100644
--- a/kernel/locking/rwsem-xadd.c
+++ b/kernel/locking/rwsem-xadd.c
@@ -246,19 +246,22 @@ struct rw_semaphore __sched *rwsem_down_read_failed(struct rw_semaphore *sem)
return sem;
}
+EXPORT_SYMBOL(rwsem_down_read_failed);
static inline bool rwsem_try_write_lock(long count, struct rw_semaphore *sem)
{
- if (!(count & RWSEM_ACTIVE_MASK)) {
- /* try acquiring the write lock */
- if (sem->count == RWSEM_WAITING_BIAS &&
- cmpxchg(&sem->count, RWSEM_WAITING_BIAS,
- RWSEM_ACTIVE_WRITE_BIAS) == RWSEM_WAITING_BIAS) {
- if (!list_is_singular(&sem->wait_list))
- rwsem_atomic_update(RWSEM_WAITING_BIAS, sem);
- return true;
- }
+ /*
+ * Try acquiring the write lock. Check count first in order
+ * to reduce unnecessary expensive cmpxchg() operations.
+ */
+ if (count == RWSEM_WAITING_BIAS &&
+ cmpxchg(&sem->count, RWSEM_WAITING_BIAS,
+ RWSEM_ACTIVE_WRITE_BIAS) == RWSEM_WAITING_BIAS) {
+ if (!list_is_singular(&sem->wait_list))
+ rwsem_atomic_update(RWSEM_WAITING_BIAS, sem);
+ return true;
}
+
return false;
}
@@ -465,6 +468,7 @@ struct rw_semaphore __sched *rwsem_down_write_failed(struct rw_semaphore *sem)
return sem;
}
+EXPORT_SYMBOL(rwsem_down_write_failed);
/*
* handle waking up a waiter on the semaphore
@@ -485,6 +489,7 @@ struct rw_semaphore *rwsem_wake(struct rw_semaphore *sem)
return sem;
}
+EXPORT_SYMBOL(rwsem_wake);
/*
* downgrade a write lock into a read lock
@@ -506,8 +511,4 @@ struct rw_semaphore *rwsem_downgrade_wake(struct rw_semaphore *sem)
return sem;
}
-
-EXPORT_SYMBOL(rwsem_down_read_failed);
-EXPORT_SYMBOL(rwsem_down_write_failed);
-EXPORT_SYMBOL(rwsem_wake);
EXPORT_SYMBOL(rwsem_downgrade_wake);
diff --git a/kernel/locking/semaphore.c b/kernel/locking/semaphore.c
index 6815171a4fff..b8120abe594b 100644
--- a/kernel/locking/semaphore.c
+++ b/kernel/locking/semaphore.c
@@ -36,7 +36,7 @@
static noinline void __down(struct semaphore *sem);
static noinline int __down_interruptible(struct semaphore *sem);
static noinline int __down_killable(struct semaphore *sem);
-static noinline int __down_timeout(struct semaphore *sem, long jiffies);
+static noinline int __down_timeout(struct semaphore *sem, long timeout);
static noinline void __up(struct semaphore *sem);
/**
@@ -145,14 +145,14 @@ EXPORT_SYMBOL(down_trylock);
/**
* down_timeout - acquire the semaphore within a specified time
* @sem: the semaphore to be acquired
- * @jiffies: how long to wait before failing
+ * @timeout: how long to wait before failing
*
* Attempts to acquire the semaphore. If no more tasks are allowed to
* acquire the semaphore, calling this function will put the task to sleep.
* If the semaphore is not released within the specified number of jiffies,
* this function returns -ETIME. It returns 0 if the semaphore was acquired.
*/
-int down_timeout(struct semaphore *sem, long jiffies)
+int down_timeout(struct semaphore *sem, long timeout)
{
unsigned long flags;
int result = 0;
@@ -161,7 +161,7 @@ int down_timeout(struct semaphore *sem, long jiffies)
if (likely(sem->count > 0))
sem->count--;
else
- result = __down_timeout(sem, jiffies);
+ result = __down_timeout(sem, timeout);
raw_spin_unlock_irqrestore(&sem->lock, flags);
return result;
@@ -248,9 +248,9 @@ static noinline int __sched __down_killable(struct semaphore *sem)
return __down_common(sem, TASK_KILLABLE, MAX_SCHEDULE_TIMEOUT);
}
-static noinline int __sched __down_timeout(struct semaphore *sem, long jiffies)
+static noinline int __sched __down_timeout(struct semaphore *sem, long timeout)
{
- return __down_common(sem, TASK_UNINTERRUPTIBLE, jiffies);
+ return __down_common(sem, TASK_UNINTERRUPTIBLE, timeout);
}
static noinline void __sched __up(struct semaphore *sem)
diff --git a/kernel/module.c b/kernel/module.c
index 03214bd288e9..65586ffa0c98 100644
--- a/kernel/module.c
+++ b/kernel/module.c
@@ -135,7 +135,7 @@ static int param_set_bool_enable_only(const char *val,
}
static const struct kernel_param_ops param_ops_bool_enable_only = {
- .flags = KERNEL_PARAM_FL_NOARG,
+ .flags = KERNEL_PARAM_OPS_FL_NOARG,
.set = param_set_bool_enable_only,
.get = param_get_bool,
};
@@ -3388,7 +3388,7 @@ static inline int is_arm_mapping_symbol(const char *str)
{
if (str[0] == '.' && str[1] == 'L')
return true;
- return str[0] == '$' && strchr("atd", str[1])
+ return str[0] == '$' && strchr("axtd", str[1])
&& (str[2] == '\0' || str[2] == '.');
}
diff --git a/kernel/params.c b/kernel/params.c
index 34f527023794..db97b791390f 100644
--- a/kernel/params.c
+++ b/kernel/params.c
@@ -19,6 +19,7 @@
#include <linux/string.h>
#include <linux/errno.h>
#include <linux/module.h>
+#include <linux/moduleparam.h>
#include <linux/device.h>
#include <linux/err.h>
#include <linux/slab.h>
@@ -83,6 +84,15 @@ bool parameq(const char *a, const char *b)
return parameqn(a, b, strlen(a)+1);
}
+static void param_check_unsafe(const struct kernel_param *kp)
+{
+ if (kp->flags & KERNEL_PARAM_FL_UNSAFE) {
+ pr_warn("Setting dangerous option %s - tainting kernel\n",
+ kp->name);
+ add_taint(TAINT_USER, LOCKDEP_STILL_OK);
+ }
+}
+
static int parse_one(char *param,
char *val,
const char *doing,
@@ -104,11 +114,12 @@ static int parse_one(char *param,
return 0;
/* No one handled NULL, so do it here. */
if (!val &&
- !(params[i].ops->flags & KERNEL_PARAM_FL_NOARG))
+ !(params[i].ops->flags & KERNEL_PARAM_OPS_FL_NOARG))
return -EINVAL;
pr_debug("handling %s with %p\n", param,
params[i].ops->set);
mutex_lock(&param_lock);
+ param_check_unsafe(&params[i]);
err = params[i].ops->set(val, &params[i]);
mutex_unlock(&param_lock);
return err;
@@ -318,7 +329,7 @@ int param_get_bool(char *buffer, const struct kernel_param *kp)
EXPORT_SYMBOL(param_get_bool);
struct kernel_param_ops param_ops_bool = {
- .flags = KERNEL_PARAM_FL_NOARG,
+ .flags = KERNEL_PARAM_OPS_FL_NOARG,
.set = param_set_bool,
.get = param_get_bool,
};
@@ -369,7 +380,7 @@ int param_set_bint(const char *val, const struct kernel_param *kp)
EXPORT_SYMBOL(param_set_bint);
struct kernel_param_ops param_ops_bint = {
- .flags = KERNEL_PARAM_FL_NOARG,
+ .flags = KERNEL_PARAM_OPS_FL_NOARG,
.set = param_set_bint,
.get = param_get_int,
};
@@ -503,8 +514,6 @@ EXPORT_SYMBOL(param_ops_string);
#define to_module_attr(n) container_of(n, struct module_attribute, attr)
#define to_module_kobject(n) container_of(n, struct module_kobject, kobj)
-extern struct kernel_param __start___param[], __stop___param[];
-
struct param_attribute
{
struct module_attribute mattr;
@@ -552,6 +561,7 @@ static ssize_t param_attr_store(struct module_attribute *mattr,
return -EPERM;
mutex_lock(&param_lock);
+ param_check_unsafe(attribute->param);
err = attribute->param->ops->set(buf, attribute->param);
mutex_unlock(&param_lock);
if (!err)
@@ -763,7 +773,7 @@ static struct module_kobject * __init locate_module_kobject(const char *name)
}
static void __init kernel_add_sysfs_param(const char *name,
- struct kernel_param *kparam,
+ const struct kernel_param *kparam,
unsigned int name_skip)
{
struct module_kobject *mk;
@@ -798,7 +808,7 @@ static void __init kernel_add_sysfs_param(const char *name,
*/
static void __init param_sysfs_builtin(void)
{
- struct kernel_param *kp;
+ const struct kernel_param *kp;
unsigned int name_len;
char modname[MODULE_NAME_LEN];
diff --git a/kernel/power/Kconfig b/kernel/power/Kconfig
index e4e4121fa327..bbef57f5bdfd 100644
--- a/kernel/power/Kconfig
+++ b/kernel/power/Kconfig
@@ -302,6 +302,10 @@ config PM_GENERIC_DOMAINS_RUNTIME
def_bool y
depends on PM_RUNTIME && PM_GENERIC_DOMAINS
+config PM_GENERIC_DOMAINS_OF
+ def_bool y
+ depends on PM_GENERIC_DOMAINS && OF
+
config CPU_PM
bool
depends on SUSPEND || CPU_IDLE
diff --git a/kernel/power/power.h b/kernel/power/power.h
index 5d49dcac2537..2df883a9d3cb 100644
--- a/kernel/power/power.h
+++ b/kernel/power/power.h
@@ -179,6 +179,7 @@ extern void swsusp_show_speed(struct timeval *, struct timeval *,
#ifdef CONFIG_SUSPEND
/* kernel/power/suspend.c */
+extern const char *pm_labels[];
extern const char *pm_states[];
extern int suspend_devices_and_enter(suspend_state_t state);
diff --git a/kernel/power/process.c b/kernel/power/process.c
index 4ee194eb524b..7b323221b9ee 100644
--- a/kernel/power/process.c
+++ b/kernel/power/process.c
@@ -129,6 +129,7 @@ int freeze_processes(void)
if (!pm_freezing)
atomic_inc(&system_freezing_cnt);
+ pm_wakeup_clear();
printk("Freezing user space processes ... ");
pm_freezing = true;
error = try_to_freeze_tasks(true);
diff --git a/kernel/power/snapshot.c b/kernel/power/snapshot.c
index c4b8093c80b3..791a61892bb5 100644
--- a/kernel/power/snapshot.c
+++ b/kernel/power/snapshot.c
@@ -1343,6 +1343,9 @@ void swsusp_free(void)
{
unsigned long fb_pfn, fr_pfn;
+ if (!forbidden_pages_map || !free_pages_map)
+ goto out;
+
memory_bm_position_reset(forbidden_pages_map);
memory_bm_position_reset(free_pages_map);
@@ -1370,6 +1373,7 @@ loop:
goto loop;
}
+out:
nr_copy_pages = 0;
nr_meta_pages = 0;
restore_pblist = NULL;
diff --git a/kernel/power/suspend.c b/kernel/power/suspend.c
index 6dadb25cb0d8..4ca9a33ff620 100644
--- a/kernel/power/suspend.c
+++ b/kernel/power/suspend.c
@@ -31,7 +31,7 @@
#include "power.h"
-static const char *pm_labels[] = { "mem", "standby", "freeze", };
+const char *pm_labels[] = { "mem", "standby", "freeze", NULL };
const char *pm_states[PM_SUSPEND_MAX];
static const struct platform_suspend_ops *suspend_ops;
@@ -146,17 +146,29 @@ static int platform_suspend_prepare(suspend_state_t state)
static int platform_suspend_prepare_late(suspend_state_t state)
{
+ return state == PM_SUSPEND_FREEZE && freeze_ops->prepare ?
+ freeze_ops->prepare() : 0;
+}
+
+static int platform_suspend_prepare_noirq(suspend_state_t state)
+{
return state != PM_SUSPEND_FREEZE && suspend_ops->prepare_late ?
suspend_ops->prepare_late() : 0;
}
-static void platform_suspend_wake(suspend_state_t state)
+static void platform_resume_noirq(suspend_state_t state)
{
if (state != PM_SUSPEND_FREEZE && suspend_ops->wake)
suspend_ops->wake();
}
-static void platform_suspend_finish(suspend_state_t state)
+static void platform_resume_early(suspend_state_t state)
+{
+ if (state == PM_SUSPEND_FREEZE && freeze_ops->restore)
+ freeze_ops->restore();
+}
+
+static void platform_resume_finish(suspend_state_t state)
{
if (state != PM_SUSPEND_FREEZE && suspend_ops->finish)
suspend_ops->finish();
@@ -172,7 +184,7 @@ static int platform_suspend_begin(suspend_state_t state)
return 0;
}
-static void platform_suspend_end(suspend_state_t state)
+static void platform_resume_end(suspend_state_t state)
{
if (state == PM_SUSPEND_FREEZE && freeze_ops && freeze_ops->end)
freeze_ops->end();
@@ -180,7 +192,7 @@ static void platform_suspend_end(suspend_state_t state)
suspend_ops->end();
}
-static void platform_suspend_recover(suspend_state_t state)
+static void platform_recover(suspend_state_t state)
{
if (state != PM_SUSPEND_FREEZE && suspend_ops->recover)
suspend_ops->recover();
@@ -265,13 +277,22 @@ static int suspend_enter(suspend_state_t state, bool *wakeup)
if (error)
goto Platform_finish;
- error = dpm_suspend_end(PMSG_SUSPEND);
+ error = dpm_suspend_late(PMSG_SUSPEND);
if (error) {
- printk(KERN_ERR "PM: Some devices failed to power down\n");
+ printk(KERN_ERR "PM: late suspend of devices failed\n");
goto Platform_finish;
}
error = platform_suspend_prepare_late(state);
if (error)
+ goto Devices_early_resume;
+
+ error = dpm_suspend_noirq(PMSG_SUSPEND);
+ if (error) {
+ printk(KERN_ERR "PM: noirq suspend of devices failed\n");
+ goto Platform_early_resume;
+ }
+ error = platform_suspend_prepare_noirq(state);
+ if (error)
goto Platform_wake;
if (suspend_test(TEST_PLATFORM))
@@ -318,11 +339,17 @@ static int suspend_enter(suspend_state_t state, bool *wakeup)
enable_nonboot_cpus();
Platform_wake:
- platform_suspend_wake(state);
- dpm_resume_start(PMSG_RESUME);
+ platform_resume_noirq(state);
+ dpm_resume_noirq(PMSG_RESUME);
+
+ Platform_early_resume:
+ platform_resume_early(state);
+
+ Devices_early_resume:
+ dpm_resume_early(PMSG_RESUME);
Platform_finish:
- platform_suspend_finish(state);
+ platform_resume_finish(state);
return error;
}
@@ -361,14 +388,16 @@ int suspend_devices_and_enter(suspend_state_t state)
suspend_test_start();
dpm_resume_end(PMSG_RESUME);
suspend_test_finish("resume devices");
+ trace_suspend_resume(TPS("resume_console"), state, true);
resume_console();
+ trace_suspend_resume(TPS("resume_console"), state, false);
Close:
- platform_suspend_end(state);
+ platform_resume_end(state);
return error;
Recover_platform:
- platform_suspend_recover(state);
+ platform_recover(state);
goto Resume_devices;
}
diff --git a/kernel/power/suspend_test.c b/kernel/power/suspend_test.c
index 2f524928b6aa..084452e34a12 100644
--- a/kernel/power/suspend_test.c
+++ b/kernel/power/suspend_test.c
@@ -22,6 +22,8 @@
#define TEST_SUSPEND_SECONDS 10
static unsigned long suspend_test_start_time;
+static u32 test_repeat_count_max = 1;
+static u32 test_repeat_count_current;
void suspend_test_start(void)
{
@@ -74,6 +76,7 @@ static void __init test_wakealarm(struct rtc_device *rtc, suspend_state_t state)
int status;
/* this may fail if the RTC hasn't been initialized */
+repeat:
status = rtc_read_time(rtc, &alm.time);
if (status < 0) {
printk(err_readtime, dev_name(&rtc->dev), status);
@@ -100,10 +103,21 @@ static void __init test_wakealarm(struct rtc_device *rtc, suspend_state_t state)
if (state == PM_SUSPEND_STANDBY) {
printk(info_test, pm_states[state]);
status = pm_suspend(state);
+ if (status < 0)
+ state = PM_SUSPEND_FREEZE;
}
+ if (state == PM_SUSPEND_FREEZE) {
+ printk(info_test, pm_states[state]);
+ status = pm_suspend(state);
+ }
+
if (status < 0)
printk(err_suspend, status);
+ test_repeat_count_current++;
+ if (test_repeat_count_current < test_repeat_count_max)
+ goto repeat;
+
/* Some platforms can't detect that the alarm triggered the
* wakeup, or (accordingly) disable it after it afterwards.
* It's supposed to give oneshot behavior; cope.
@@ -129,24 +143,36 @@ static int __init has_wakealarm(struct device *dev, const void *data)
* at startup time. They're normally disabled, for faster boot and because
* we can't know which states really work on this particular system.
*/
-static suspend_state_t test_state __initdata = PM_SUSPEND_ON;
+static const char *test_state_label __initdata;
static char warn_bad_state[] __initdata =
KERN_WARNING "PM: can't test '%s' suspend state\n";
static int __init setup_test_suspend(char *value)
{
- suspend_state_t i;
+ int i;
+ char *repeat;
+ char *suspend_type;
- /* "=mem" ==> "mem" */
+ /* example : "=mem[,N]" ==> "mem[,N]" */
value++;
- for (i = PM_SUSPEND_MIN; i < PM_SUSPEND_MAX; i++)
- if (!strcmp(pm_states[i], value)) {
- test_state = i;
+ suspend_type = strsep(&value, ",");
+ if (!suspend_type)
+ return 0;
+
+ repeat = strsep(&value, ",");
+ if (repeat) {
+ if (kstrtou32(repeat, 0, &test_repeat_count_max))
+ return 0;
+ }
+
+ for (i = 0; pm_labels[i]; i++)
+ if (!strcmp(pm_labels[i], suspend_type)) {
+ test_state_label = pm_labels[i];
return 0;
}
- printk(warn_bad_state, value);
+ printk(warn_bad_state, suspend_type);
return 0;
}
__setup("test_suspend", setup_test_suspend);
@@ -158,13 +184,21 @@ static int __init test_suspend(void)
struct rtc_device *rtc = NULL;
struct device *dev;
+ suspend_state_t test_state;
/* PM is initialized by now; is that state testable? */
- if (test_state == PM_SUSPEND_ON)
- goto done;
- if (!pm_states[test_state]) {
- printk(warn_bad_state, pm_states[test_state]);
- goto done;
+ if (!test_state_label)
+ return 0;
+
+ for (test_state = PM_SUSPEND_MIN; test_state < PM_SUSPEND_MAX; test_state++) {
+ const char *state_label = pm_states[test_state];
+
+ if (state_label && !strcmp(test_state_label, state_label))
+ break;
+ }
+ if (test_state == PM_SUSPEND_MAX) {
+ printk(warn_bad_state, test_state_label);
+ return 0;
}
/* RTCs have initialized by now too ... can we use one? */
@@ -173,13 +207,12 @@ static int __init test_suspend(void)
rtc = rtc_class_open(dev_name(dev));
if (!rtc) {
printk(warn_no_rtc);
- goto done;
+ return 0;
}
/* go for it */
test_wakealarm(rtc, test_state);
rtc_class_close(rtc);
-done:
return 0;
}
late_initcall(test_suspend);
diff --git a/kernel/printk/printk.c b/kernel/printk/printk.c
index 960fbfc6cd0a..ced2b84b1cb7 100644
--- a/kernel/printk/printk.c
+++ b/kernel/printk/printk.c
@@ -267,7 +267,6 @@ static u32 clear_idx;
#define LOG_ALIGN __alignof__(struct printk_log)
#endif
#define __LOG_BUF_LEN (1 << CONFIG_LOG_BUF_SHIFT)
-#define __LOG_CPU_MAX_BUF_LEN (1 << CONFIG_LOG_CPU_MAX_BUF_SHIFT)
static char __log_buf[__LOG_BUF_LEN] __aligned(LOG_ALIGN);
static char *log_buf = __log_buf;
static u32 log_buf_len = __LOG_BUF_LEN;
@@ -519,14 +518,13 @@ struct devkmsg_user {
char buf[8192];
};
-static ssize_t devkmsg_writev(struct kiocb *iocb, const struct iovec *iv,
- unsigned long count, loff_t pos)
+static ssize_t devkmsg_write(struct kiocb *iocb, struct iov_iter *from)
{
char *buf, *line;
int i;
int level = default_message_loglevel;
int facility = 1; /* LOG_USER */
- size_t len = iov_length(iv, count);
+ size_t len = iocb->ki_nbytes;
ssize_t ret = len;
if (len > LOG_LINE_MAX)
@@ -535,13 +533,10 @@ static ssize_t devkmsg_writev(struct kiocb *iocb, const struct iovec *iv,
if (buf == NULL)
return -ENOMEM;
- line = buf;
- for (i = 0; i < count; i++) {
- if (copy_from_user(line, iv[i].iov_base, iv[i].iov_len)) {
- ret = -EFAULT;
- goto out;
- }
- line += iv[i].iov_len;
+ buf[len] = '\0';
+ if (copy_from_iter(buf, len, from) != len) {
+ kfree(buf);
+ return -EFAULT;
}
/*
@@ -567,10 +562,8 @@ static ssize_t devkmsg_writev(struct kiocb *iocb, const struct iovec *iv,
line = endp;
}
}
- line[len] = '\0';
printk_emit(facility, level, NULL, 0, "%s", line);
-out:
kfree(buf);
return ret;
}
@@ -802,7 +795,7 @@ static int devkmsg_release(struct inode *inode, struct file *file)
const struct file_operations kmsg_fops = {
.open = devkmsg_open,
.read = devkmsg_read,
- .aio_write = devkmsg_writev,
+ .write_iter = devkmsg_write,
.llseek = devkmsg_llseek,
.poll = devkmsg_poll,
.release = devkmsg_release,
@@ -858,6 +851,9 @@ static int __init log_buf_len_setup(char *str)
}
early_param("log_buf_len", log_buf_len_setup);
+#ifdef CONFIG_SMP
+#define __LOG_CPU_MAX_BUF_LEN (1 << CONFIG_LOG_CPU_MAX_BUF_SHIFT)
+
static void __init log_buf_add_cpu(void)
{
unsigned int cpu_extra;
@@ -884,6 +880,9 @@ static void __init log_buf_add_cpu(void)
log_buf_len_update(cpu_extra + __LOG_BUF_LEN);
}
+#else /* !CONFIG_SMP */
+static inline void log_buf_add_cpu(void) {}
+#endif /* CONFIG_SMP */
void __init setup_log_buf(int early)
{
@@ -1665,27 +1664,22 @@ asmlinkage int vprintk_emit(int facility, int level,
raw_spin_lock(&logbuf_lock);
logbuf_cpu = this_cpu;
- if (recursion_bug) {
+ if (unlikely(recursion_bug)) {
static const char recursion_msg[] =
"BUG: recent printk recursion!";
recursion_bug = 0;
- text_len = strlen(recursion_msg);
/* emit KERN_CRIT message */
printed_len += log_store(0, 2, LOG_PREFIX|LOG_NEWLINE, 0,
- NULL, 0, recursion_msg, text_len);
+ NULL, 0, recursion_msg,
+ strlen(recursion_msg));
}
/*
* The printf needs to come first; we need the syslog
* prefix which might be passed-in as a parameter.
*/
- if (in_sched)
- text_len = scnprintf(text, sizeof(textbuf),
- KERN_WARNING "[sched_delayed] ");
-
- text_len += vscnprintf(text + text_len,
- sizeof(textbuf) - text_len, fmt, args);
+ text_len = vscnprintf(text, sizeof(textbuf), fmt, args);
/* mark and strip a trailing newline */
if (text_len && text[text_len-1] == '\n') {
diff --git a/kernel/rcu/rcutorture.c b/kernel/rcu/rcutorture.c
index 948a7693748e..240fa9094f83 100644
--- a/kernel/rcu/rcutorture.c
+++ b/kernel/rcu/rcutorture.c
@@ -49,11 +49,19 @@
#include <linux/trace_clock.h>
#include <asm/byteorder.h>
#include <linux/torture.h>
+#include <linux/vmalloc.h>
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Paul E. McKenney <paulmck@us.ibm.com> and Josh Triplett <josh@joshtriplett.org>");
+torture_param(int, cbflood_inter_holdoff, HZ,
+ "Holdoff between floods (jiffies)");
+torture_param(int, cbflood_intra_holdoff, 1,
+ "Holdoff between bursts (jiffies)");
+torture_param(int, cbflood_n_burst, 3, "# bursts in flood, zero to disable");
+torture_param(int, cbflood_n_per_burst, 20000,
+ "# callbacks per burst in flood");
torture_param(int, fqs_duration, 0,
"Duration of fqs bursts (us), 0 to disable");
torture_param(int, fqs_holdoff, 0, "Holdoff time within fqs bursts (us)");
@@ -96,10 +104,12 @@ module_param(torture_type, charp, 0444);
MODULE_PARM_DESC(torture_type, "Type of RCU to torture (rcu, rcu_bh, ...)");
static int nrealreaders;
+static int ncbflooders;
static struct task_struct *writer_task;
static struct task_struct **fakewriter_tasks;
static struct task_struct **reader_tasks;
static struct task_struct *stats_task;
+static struct task_struct **cbflood_task;
static struct task_struct *fqs_task;
static struct task_struct *boost_tasks[NR_CPUS];
static struct task_struct *stall_task;
@@ -138,6 +148,7 @@ static long n_rcu_torture_boosts;
static long n_rcu_torture_timers;
static long n_barrier_attempts;
static long n_barrier_successes;
+static atomic_long_t n_cbfloods;
static struct list_head rcu_torture_removed;
static int rcu_torture_writer_state;
@@ -157,9 +168,9 @@ static int rcu_torture_writer_state;
#else
#define RCUTORTURE_RUNNABLE_INIT 0
#endif
-int rcutorture_runnable = RCUTORTURE_RUNNABLE_INIT;
-module_param(rcutorture_runnable, int, 0444);
-MODULE_PARM_DESC(rcutorture_runnable, "Start rcutorture at boot");
+static int torture_runnable = RCUTORTURE_RUNNABLE_INIT;
+module_param(torture_runnable, int, 0444);
+MODULE_PARM_DESC(torture_runnable, "Start rcutorture at boot");
#if defined(CONFIG_RCU_BOOST) && !defined(CONFIG_HOTPLUG_CPU)
#define rcu_can_boost() 1
@@ -182,7 +193,7 @@ static u64 notrace rcu_trace_clock_local(void)
#endif /* #else #ifdef CONFIG_RCU_TRACE */
static unsigned long boost_starttime; /* jiffies of next boost test start. */
-DEFINE_MUTEX(boost_mutex); /* protect setting boost_starttime */
+static DEFINE_MUTEX(boost_mutex); /* protect setting boost_starttime */
/* and boost task create/destroy. */
static atomic_t barrier_cbs_count; /* Barrier callbacks registered. */
static bool barrier_phase; /* Test phase. */
@@ -242,7 +253,7 @@ struct rcu_torture_ops {
void (*call)(struct rcu_head *head, void (*func)(struct rcu_head *rcu));
void (*cb_barrier)(void);
void (*fqs)(void);
- void (*stats)(char *page);
+ void (*stats)(void);
int irq_capable;
int can_boost;
const char *name;
@@ -525,21 +536,21 @@ static void srcu_torture_barrier(void)
srcu_barrier(&srcu_ctl);
}
-static void srcu_torture_stats(char *page)
+static void srcu_torture_stats(void)
{
int cpu;
int idx = srcu_ctl.completed & 0x1;
- page += sprintf(page, "%s%s per-CPU(idx=%d):",
- torture_type, TORTURE_FLAG, idx);
+ pr_alert("%s%s per-CPU(idx=%d):",
+ torture_type, TORTURE_FLAG, idx);
for_each_possible_cpu(cpu) {
long c0, c1;
c0 = (long)per_cpu_ptr(srcu_ctl.per_cpu_ref, cpu)->c[!idx];
c1 = (long)per_cpu_ptr(srcu_ctl.per_cpu_ref, cpu)->c[idx];
- page += sprintf(page, " %d(%ld,%ld)", cpu, c0, c1);
+ pr_cont(" %d(%ld,%ld)", cpu, c0, c1);
}
- sprintf(page, "\n");
+ pr_cont("\n");
}
static void srcu_torture_synchronize_expedited(void)
@@ -601,6 +612,52 @@ static struct rcu_torture_ops sched_ops = {
.name = "sched"
};
+#ifdef CONFIG_TASKS_RCU
+
+/*
+ * Definitions for RCU-tasks torture testing.
+ */
+
+static int tasks_torture_read_lock(void)
+{
+ return 0;
+}
+
+static void tasks_torture_read_unlock(int idx)
+{
+}
+
+static void rcu_tasks_torture_deferred_free(struct rcu_torture *p)
+{
+ call_rcu_tasks(&p->rtort_rcu, rcu_torture_cb);
+}
+
+static struct rcu_torture_ops tasks_ops = {
+ .ttype = RCU_TASKS_FLAVOR,
+ .init = rcu_sync_torture_init,
+ .readlock = tasks_torture_read_lock,
+ .read_delay = rcu_read_delay, /* just reuse rcu's version. */
+ .readunlock = tasks_torture_read_unlock,
+ .completed = rcu_no_completed,
+ .deferred_free = rcu_tasks_torture_deferred_free,
+ .sync = synchronize_rcu_tasks,
+ .exp_sync = synchronize_rcu_tasks,
+ .call = call_rcu_tasks,
+ .cb_barrier = rcu_barrier_tasks,
+ .fqs = NULL,
+ .stats = NULL,
+ .irq_capable = 1,
+ .name = "tasks"
+};
+
+#define RCUTORTURE_TASKS_OPS &tasks_ops,
+
+#else /* #ifdef CONFIG_TASKS_RCU */
+
+#define RCUTORTURE_TASKS_OPS
+
+#endif /* #else #ifdef CONFIG_TASKS_RCU */
+
/*
* RCU torture priority-boost testing. Runs one real-time thread per
* CPU for moderate bursts, repeatedly registering RCU callbacks and
@@ -667,7 +724,7 @@ static int rcu_torture_boost(void *arg)
}
call_rcu_time = jiffies;
}
- cond_resched();
+ cond_resched_rcu_qs();
stutter_wait("rcu_torture_boost");
if (torture_must_stop())
goto checkwait;
@@ -707,6 +764,58 @@ checkwait: stutter_wait("rcu_torture_boost");
return 0;
}
+static void rcu_torture_cbflood_cb(struct rcu_head *rhp)
+{
+}
+
+/*
+ * RCU torture callback-flood kthread. Repeatedly induces bursts of calls
+ * to call_rcu() or analogous, increasing the probability of occurrence
+ * of callback-overflow corner cases.
+ */
+static int
+rcu_torture_cbflood(void *arg)
+{
+ int err = 1;
+ int i;
+ int j;
+ struct rcu_head *rhp;
+
+ if (cbflood_n_per_burst > 0 &&
+ cbflood_inter_holdoff > 0 &&
+ cbflood_intra_holdoff > 0 &&
+ cur_ops->call &&
+ cur_ops->cb_barrier) {
+ rhp = vmalloc(sizeof(*rhp) *
+ cbflood_n_burst * cbflood_n_per_burst);
+ err = !rhp;
+ }
+ if (err) {
+ VERBOSE_TOROUT_STRING("rcu_torture_cbflood disabled: Bad args or OOM");
+ while (!torture_must_stop())
+ schedule_timeout_interruptible(HZ);
+ return 0;
+ }
+ VERBOSE_TOROUT_STRING("rcu_torture_cbflood task started");
+ do {
+ schedule_timeout_interruptible(cbflood_inter_holdoff);
+ atomic_long_inc(&n_cbfloods);
+ WARN_ON(signal_pending(current));
+ for (i = 0; i < cbflood_n_burst; i++) {
+ for (j = 0; j < cbflood_n_per_burst; j++) {
+ cur_ops->call(&rhp[i * cbflood_n_per_burst + j],
+ rcu_torture_cbflood_cb);
+ }
+ schedule_timeout_interruptible(cbflood_intra_holdoff);
+ WARN_ON(signal_pending(current));
+ }
+ cur_ops->cb_barrier();
+ stutter_wait("rcu_torture_cbflood");
+ } while (!torture_must_stop());
+ torture_kthread_stopping("rcu_torture_cbflood");
+ return 0;
+}
+
/*
* RCU torture force-quiescent-state kthread. Repeatedly induces
* bursts of calls to force_quiescent_state(), increasing the probability
@@ -1019,7 +1128,7 @@ rcu_torture_reader(void *arg)
__this_cpu_inc(rcu_torture_batch[completed]);
preempt_enable();
cur_ops->readunlock(idx);
- cond_resched();
+ cond_resched_rcu_qs();
stutter_wait("rcu_torture_reader");
} while (!torture_must_stop());
if (irqreader && cur_ops->irq_capable) {
@@ -1031,10 +1140,15 @@ rcu_torture_reader(void *arg)
}
/*
- * Create an RCU-torture statistics message in the specified buffer.
+ * Print torture statistics. Caller must ensure that there is only
+ * one call to this function at a given time!!! This is normally
+ * accomplished by relying on the module system to only have one copy
+ * of the module loaded, and then by giving the rcu_torture_stats
+ * kthread full control (or the init/cleanup functions when rcu_torture_stats
+ * thread is not running).
*/
static void
-rcu_torture_printk(char *page)
+rcu_torture_stats_print(void)
{
int cpu;
int i;
@@ -1052,55 +1166,61 @@ rcu_torture_printk(char *page)
if (pipesummary[i] != 0)
break;
}
- page += sprintf(page, "%s%s ", torture_type, TORTURE_FLAG);
- page += sprintf(page,
- "rtc: %p ver: %lu tfle: %d rta: %d rtaf: %d rtf: %d ",
- rcu_torture_current,
- rcu_torture_current_version,
- list_empty(&rcu_torture_freelist),
- atomic_read(&n_rcu_torture_alloc),
- atomic_read(&n_rcu_torture_alloc_fail),
- atomic_read(&n_rcu_torture_free));
- page += sprintf(page, "rtmbe: %d rtbke: %ld rtbre: %ld ",
- atomic_read(&n_rcu_torture_mberror),
- n_rcu_torture_boost_ktrerror,
- n_rcu_torture_boost_rterror);
- page += sprintf(page, "rtbf: %ld rtb: %ld nt: %ld ",
- n_rcu_torture_boost_failure,
- n_rcu_torture_boosts,
- n_rcu_torture_timers);
- page = torture_onoff_stats(page);
- page += sprintf(page, "barrier: %ld/%ld:%ld",
- n_barrier_successes,
- n_barrier_attempts,
- n_rcu_torture_barrier_error);
- page += sprintf(page, "\n%s%s ", torture_type, TORTURE_FLAG);
+
+ pr_alert("%s%s ", torture_type, TORTURE_FLAG);
+ pr_cont("rtc: %p ver: %lu tfle: %d rta: %d rtaf: %d rtf: %d ",
+ rcu_torture_current,
+ rcu_torture_current_version,
+ list_empty(&rcu_torture_freelist),
+ atomic_read(&n_rcu_torture_alloc),
+ atomic_read(&n_rcu_torture_alloc_fail),
+ atomic_read(&n_rcu_torture_free));
+ pr_cont("rtmbe: %d rtbke: %ld rtbre: %ld ",
+ atomic_read(&n_rcu_torture_mberror),
+ n_rcu_torture_boost_ktrerror,
+ n_rcu_torture_boost_rterror);
+ pr_cont("rtbf: %ld rtb: %ld nt: %ld ",
+ n_rcu_torture_boost_failure,
+ n_rcu_torture_boosts,
+ n_rcu_torture_timers);
+ torture_onoff_stats();
+ pr_cont("barrier: %ld/%ld:%ld ",
+ n_barrier_successes,
+ n_barrier_attempts,
+ n_rcu_torture_barrier_error);
+ pr_cont("cbflood: %ld\n", atomic_long_read(&n_cbfloods));
+
+ pr_alert("%s%s ", torture_type, TORTURE_FLAG);
if (atomic_read(&n_rcu_torture_mberror) != 0 ||
n_rcu_torture_barrier_error != 0 ||
n_rcu_torture_boost_ktrerror != 0 ||
n_rcu_torture_boost_rterror != 0 ||
n_rcu_torture_boost_failure != 0 ||
i > 1) {
- page += sprintf(page, "!!! ");
+ pr_cont("%s", "!!! ");
atomic_inc(&n_rcu_torture_error);
WARN_ON_ONCE(1);
}
- page += sprintf(page, "Reader Pipe: ");
+ pr_cont("Reader Pipe: ");
for (i = 0; i < RCU_TORTURE_PIPE_LEN + 1; i++)
- page += sprintf(page, " %ld", pipesummary[i]);
- page += sprintf(page, "\n%s%s ", torture_type, TORTURE_FLAG);
- page += sprintf(page, "Reader Batch: ");
+ pr_cont(" %ld", pipesummary[i]);
+ pr_cont("\n");
+
+ pr_alert("%s%s ", torture_type, TORTURE_FLAG);
+ pr_cont("Reader Batch: ");
for (i = 0; i < RCU_TORTURE_PIPE_LEN + 1; i++)
- page += sprintf(page, " %ld", batchsummary[i]);
- page += sprintf(page, "\n%s%s ", torture_type, TORTURE_FLAG);
- page += sprintf(page, "Free-Block Circulation: ");
+ pr_cont(" %ld", batchsummary[i]);
+ pr_cont("\n");
+
+ pr_alert("%s%s ", torture_type, TORTURE_FLAG);
+ pr_cont("Free-Block Circulation: ");
for (i = 0; i < RCU_TORTURE_PIPE_LEN + 1; i++) {
- page += sprintf(page, " %d",
- atomic_read(&rcu_torture_wcount[i]));
+ pr_cont(" %d", atomic_read(&rcu_torture_wcount[i]));
}
- page += sprintf(page, "\n");
+ pr_cont("\n");
+
if (cur_ops->stats)
- cur_ops->stats(page);
+ cur_ops->stats();
if (rtcv_snap == rcu_torture_current_version &&
rcu_torture_current != NULL) {
int __maybe_unused flags;
@@ -1109,10 +1229,9 @@ rcu_torture_printk(char *page)
rcutorture_get_gp_data(cur_ops->ttype,
&flags, &gpnum, &completed);
- page += sprintf(page,
- "??? Writer stall state %d g%lu c%lu f%#x\n",
- rcu_torture_writer_state,
- gpnum, completed, flags);
+ pr_alert("??? Writer stall state %d g%lu c%lu f%#x\n",
+ rcu_torture_writer_state,
+ gpnum, completed, flags);
show_rcu_gp_kthreads();
rcutorture_trace_dump();
}
@@ -1120,30 +1239,6 @@ rcu_torture_printk(char *page)
}
/*
- * Print torture statistics. Caller must ensure that there is only
- * one call to this function at a given time!!! This is normally
- * accomplished by relying on the module system to only have one copy
- * of the module loaded, and then by giving the rcu_torture_stats
- * kthread full control (or the init/cleanup functions when rcu_torture_stats
- * thread is not running).
- */
-static void
-rcu_torture_stats_print(void)
-{
- int size = nr_cpu_ids * 200 + 8192;
- char *buf;
-
- buf = kmalloc(size, GFP_KERNEL);
- if (!buf) {
- pr_err("rcu-torture: Out of memory, need: %d", size);
- return;
- }
- rcu_torture_printk(buf);
- pr_alert("%s", buf);
- kfree(buf);
-}
-
-/*
* Periodically prints torture statistics, if periodic statistics printing
* was specified via the stat_interval module parameter.
*/
@@ -1295,7 +1390,8 @@ static int rcu_torture_barrier_cbs(void *arg)
if (atomic_dec_and_test(&barrier_cbs_count))
wake_up(&barrier_wq);
} while (!torture_must_stop());
- cur_ops->cb_barrier();
+ if (cur_ops->cb_barrier != NULL)
+ cur_ops->cb_barrier();
destroy_rcu_head_on_stack(&rcu);
torture_kthread_stopping("rcu_torture_barrier_cbs");
return 0;
@@ -1418,7 +1514,7 @@ rcu_torture_cleanup(void)
int i;
rcutorture_record_test_transition();
- if (torture_cleanup()) {
+ if (torture_cleanup_begin()) {
if (cur_ops->cb_barrier != NULL)
cur_ops->cb_barrier();
return;
@@ -1447,6 +1543,8 @@ rcu_torture_cleanup(void)
torture_stop_kthread(rcu_torture_stats, stats_task);
torture_stop_kthread(rcu_torture_fqs, fqs_task);
+ for (i = 0; i < ncbflooders; i++)
+ torture_stop_kthread(rcu_torture_cbflood, cbflood_task[i]);
if ((test_boost == 1 && cur_ops->can_boost) ||
test_boost == 2) {
unregister_cpu_notifier(&rcutorture_cpu_nb);
@@ -1468,6 +1566,7 @@ rcu_torture_cleanup(void)
"End of test: RCU_HOTPLUG");
else
rcu_torture_print_module_parms(cur_ops, "End of test: SUCCESS");
+ torture_cleanup_end();
}
#ifdef CONFIG_DEBUG_OBJECTS_RCU_HEAD
@@ -1534,9 +1633,10 @@ rcu_torture_init(void)
int firsterr = 0;
static struct rcu_torture_ops *torture_ops[] = {
&rcu_ops, &rcu_bh_ops, &rcu_busted_ops, &srcu_ops, &sched_ops,
+ RCUTORTURE_TASKS_OPS
};
- if (!torture_init_begin(torture_type, verbose, &rcutorture_runnable))
+ if (!torture_init_begin(torture_type, verbose, &torture_runnable))
return -EBUSY;
/* Process args and tell the world that the torturer is on the job. */
@@ -1693,6 +1793,24 @@ rcu_torture_init(void)
goto unwind;
if (object_debug)
rcu_test_debug_objects();
+ if (cbflood_n_burst > 0) {
+ /* Create the cbflood threads */
+ ncbflooders = (num_online_cpus() + 3) / 4;
+ cbflood_task = kcalloc(ncbflooders, sizeof(*cbflood_task),
+ GFP_KERNEL);
+ if (!cbflood_task) {
+ VERBOSE_TOROUT_ERRSTRING("out of memory");
+ firsterr = -ENOMEM;
+ goto unwind;
+ }
+ for (i = 0; i < ncbflooders; i++) {
+ firsterr = torture_create_kthread(rcu_torture_cbflood,
+ NULL,
+ cbflood_task[i]);
+ if (firsterr)
+ goto unwind;
+ }
+ }
rcutorture_record_test_transition();
torture_init_end();
return 0;
diff --git a/kernel/rcu/tiny.c b/kernel/rcu/tiny.c
index d9efcc13008c..c0623fc47125 100644
--- a/kernel/rcu/tiny.c
+++ b/kernel/rcu/tiny.c
@@ -51,7 +51,7 @@ static long long rcu_dynticks_nesting = DYNTICK_TASK_EXIT_IDLE;
#include "tiny_plugin.h"
-/* Common code for rcu_idle_enter() and rcu_irq_exit(), see kernel/rcutree.c. */
+/* Common code for rcu_idle_enter() and rcu_irq_exit(), see kernel/rcu/tree.c. */
static void rcu_idle_enter_common(long long newval)
{
if (newval) {
@@ -62,7 +62,7 @@ static void rcu_idle_enter_common(long long newval)
}
RCU_TRACE(trace_rcu_dyntick(TPS("Start"),
rcu_dynticks_nesting, newval));
- if (!is_idle_task(current)) {
+ if (IS_ENABLED(CONFIG_RCU_TRACE) && !is_idle_task(current)) {
struct task_struct *idle __maybe_unused = idle_task(smp_processor_id());
RCU_TRACE(trace_rcu_dyntick(TPS("Entry error: not idle task"),
@@ -72,7 +72,7 @@ static void rcu_idle_enter_common(long long newval)
current->pid, current->comm,
idle->pid, idle->comm); /* must be idle task! */
}
- rcu_sched_qs(0); /* implies rcu_bh_qsctr_inc(0) */
+ rcu_sched_qs(); /* implies rcu_bh_inc() */
barrier();
rcu_dynticks_nesting = newval;
}
@@ -114,7 +114,7 @@ void rcu_irq_exit(void)
}
EXPORT_SYMBOL_GPL(rcu_irq_exit);
-/* Common code for rcu_idle_exit() and rcu_irq_enter(), see kernel/rcutree.c. */
+/* Common code for rcu_idle_exit() and rcu_irq_enter(), see kernel/rcu/tree.c. */
static void rcu_idle_exit_common(long long oldval)
{
if (oldval) {
@@ -123,7 +123,7 @@ static void rcu_idle_exit_common(long long oldval)
return;
}
RCU_TRACE(trace_rcu_dyntick(TPS("End"), oldval, rcu_dynticks_nesting));
- if (!is_idle_task(current)) {
+ if (IS_ENABLED(CONFIG_RCU_TRACE) && !is_idle_task(current)) {
struct task_struct *idle __maybe_unused = idle_task(smp_processor_id());
RCU_TRACE(trace_rcu_dyntick(TPS("Exit error: not idle task"),
@@ -217,7 +217,7 @@ static int rcu_qsctr_help(struct rcu_ctrlblk *rcp)
* are at it, given that any rcu quiescent state is also an rcu_bh
* quiescent state. Use "+" instead of "||" to defeat short circuiting.
*/
-void rcu_sched_qs(int cpu)
+void rcu_sched_qs(void)
{
unsigned long flags;
@@ -231,7 +231,7 @@ void rcu_sched_qs(int cpu)
/*
* Record an rcu_bh quiescent state.
*/
-void rcu_bh_qs(int cpu)
+void rcu_bh_qs(void)
{
unsigned long flags;
@@ -251,9 +251,11 @@ void rcu_check_callbacks(int cpu, int user)
{
RCU_TRACE(check_cpu_stalls());
if (user || rcu_is_cpu_rrupt_from_idle())
- rcu_sched_qs(cpu);
+ rcu_sched_qs();
else if (!in_softirq())
- rcu_bh_qs(cpu);
+ rcu_bh_qs();
+ if (user)
+ rcu_note_voluntary_context_switch(current);
}
/*
diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c
index 1b70cb6fbe3c..133e47223095 100644
--- a/kernel/rcu/tree.c
+++ b/kernel/rcu/tree.c
@@ -79,9 +79,18 @@ static struct lock_class_key rcu_fqs_class[RCU_NUM_LVLS];
* the tracing userspace tools to be able to decipher the string
* address to the matching string.
*/
-#define RCU_STATE_INITIALIZER(sname, sabbr, cr) \
+#ifdef CONFIG_TRACING
+# define DEFINE_RCU_TPS(sname) \
static char sname##_varname[] = #sname; \
-static const char *tp_##sname##_varname __used __tracepoint_string = sname##_varname; \
+static const char *tp_##sname##_varname __used __tracepoint_string = sname##_varname;
+# define RCU_STATE_NAME(sname) sname##_varname
+#else
+# define DEFINE_RCU_TPS(sname)
+# define RCU_STATE_NAME(sname) __stringify(sname)
+#endif
+
+#define RCU_STATE_INITIALIZER(sname, sabbr, cr) \
+DEFINE_RCU_TPS(sname) \
struct rcu_state sname##_state = { \
.level = { &sname##_state.node[0] }, \
.call = cr, \
@@ -93,7 +102,7 @@ struct rcu_state sname##_state = { \
.orphan_donetail = &sname##_state.orphan_donelist, \
.barrier_mutex = __MUTEX_INITIALIZER(sname##_state.barrier_mutex), \
.onoff_mutex = __MUTEX_INITIALIZER(sname##_state.onoff_mutex), \
- .name = sname##_varname, \
+ .name = RCU_STATE_NAME(sname), \
.abbr = sabbr, \
}; \
DEFINE_PER_CPU(struct rcu_data, sname##_data)
@@ -188,22 +197,24 @@ static int rcu_gp_in_progress(struct rcu_state *rsp)
* one since the start of the grace period, this just sets a flag.
* The caller must have disabled preemption.
*/
-void rcu_sched_qs(int cpu)
+void rcu_sched_qs(void)
{
- struct rcu_data *rdp = &per_cpu(rcu_sched_data, cpu);
-
- if (rdp->passed_quiesce == 0)
- trace_rcu_grace_period(TPS("rcu_sched"), rdp->gpnum, TPS("cpuqs"));
- rdp->passed_quiesce = 1;
+ if (!__this_cpu_read(rcu_sched_data.passed_quiesce)) {
+ trace_rcu_grace_period(TPS("rcu_sched"),
+ __this_cpu_read(rcu_sched_data.gpnum),
+ TPS("cpuqs"));
+ __this_cpu_write(rcu_sched_data.passed_quiesce, 1);
+ }
}
-void rcu_bh_qs(int cpu)
+void rcu_bh_qs(void)
{
- struct rcu_data *rdp = &per_cpu(rcu_bh_data, cpu);
-
- if (rdp->passed_quiesce == 0)
- trace_rcu_grace_period(TPS("rcu_bh"), rdp->gpnum, TPS("cpuqs"));
- rdp->passed_quiesce = 1;
+ if (!__this_cpu_read(rcu_bh_data.passed_quiesce)) {
+ trace_rcu_grace_period(TPS("rcu_bh"),
+ __this_cpu_read(rcu_bh_data.gpnum),
+ TPS("cpuqs"));
+ __this_cpu_write(rcu_bh_data.passed_quiesce, 1);
+ }
}
static DEFINE_PER_CPU(int, rcu_sched_qs_mask);
@@ -278,7 +289,7 @@ static void rcu_momentary_dyntick_idle(void)
void rcu_note_context_switch(int cpu)
{
trace_rcu_utilization(TPS("Start context switch"));
- rcu_sched_qs(cpu);
+ rcu_sched_qs();
rcu_preempt_note_context_switch(cpu);
if (unlikely(raw_cpu_read(rcu_sched_qs_mask)))
rcu_momentary_dyntick_idle();
@@ -526,6 +537,7 @@ static void rcu_eqs_enter_common(struct rcu_dynticks *rdtp, long long oldval,
atomic_inc(&rdtp->dynticks);
smp_mb__after_atomic(); /* Force ordering with next sojourn. */
WARN_ON_ONCE(atomic_read(&rdtp->dynticks) & 0x1);
+ rcu_dynticks_task_enter();
/*
* It is illegal to enter an extended quiescent state while
@@ -642,6 +654,7 @@ void rcu_irq_exit(void)
static void rcu_eqs_exit_common(struct rcu_dynticks *rdtp, long long oldval,
int user)
{
+ rcu_dynticks_task_exit();
smp_mb__before_atomic(); /* Force ordering w/previous sojourn. */
atomic_inc(&rdtp->dynticks);
/* CPUs seeing atomic_inc() must see later RCU read-side crit sects */
@@ -819,7 +832,7 @@ bool notrace __rcu_is_watching(void)
*/
bool notrace rcu_is_watching(void)
{
- int ret;
+ bool ret;
preempt_disable();
ret = __rcu_is_watching();
@@ -1647,7 +1660,7 @@ static int rcu_gp_init(struct rcu_state *rsp)
rnp->level, rnp->grplo,
rnp->grphi, rnp->qsmask);
raw_spin_unlock_irq(&rnp->lock);
- cond_resched();
+ cond_resched_rcu_qs();
}
mutex_unlock(&rsp->onoff_mutex);
@@ -1668,7 +1681,7 @@ static int rcu_gp_fqs(struct rcu_state *rsp, int fqs_state_in)
if (fqs_state == RCU_SAVE_DYNTICK) {
/* Collect dyntick-idle snapshots. */
if (is_sysidle_rcu_state(rsp)) {
- isidle = 1;
+ isidle = true;
maxj = jiffies - ULONG_MAX / 4;
}
force_qs_rnp(rsp, dyntick_save_progress_counter,
@@ -1677,14 +1690,15 @@ static int rcu_gp_fqs(struct rcu_state *rsp, int fqs_state_in)
fqs_state = RCU_FORCE_QS;
} else {
/* Handle dyntick-idle and offline CPUs. */
- isidle = 0;
+ isidle = false;
force_qs_rnp(rsp, rcu_implicit_dynticks_qs, &isidle, &maxj);
}
/* Clear flag to prevent immediate re-entry. */
if (ACCESS_ONCE(rsp->gp_flags) & RCU_GP_FLAG_FQS) {
raw_spin_lock_irq(&rnp->lock);
smp_mb__after_unlock_lock();
- ACCESS_ONCE(rsp->gp_flags) &= ~RCU_GP_FLAG_FQS;
+ ACCESS_ONCE(rsp->gp_flags) =
+ ACCESS_ONCE(rsp->gp_flags) & ~RCU_GP_FLAG_FQS;
raw_spin_unlock_irq(&rnp->lock);
}
return fqs_state;
@@ -1736,7 +1750,7 @@ static void rcu_gp_cleanup(struct rcu_state *rsp)
/* smp_mb() provided by prior unlock-lock pair. */
nocb += rcu_future_gp_cleanup(rsp, rnp);
raw_spin_unlock_irq(&rnp->lock);
- cond_resched();
+ cond_resched_rcu_qs();
}
rnp = rcu_get_root(rsp);
raw_spin_lock_irq(&rnp->lock);
@@ -1785,8 +1799,8 @@ static int __noreturn rcu_gp_kthread(void *arg)
/* Locking provides needed memory barrier. */
if (rcu_gp_init(rsp))
break;
- cond_resched();
- flush_signals(current);
+ cond_resched_rcu_qs();
+ WARN_ON(signal_pending(current));
trace_rcu_grace_period(rsp->name,
ACCESS_ONCE(rsp->gpnum),
TPS("reqwaitsig"));
@@ -1828,11 +1842,11 @@ static int __noreturn rcu_gp_kthread(void *arg)
trace_rcu_grace_period(rsp->name,
ACCESS_ONCE(rsp->gpnum),
TPS("fqsend"));
- cond_resched();
+ cond_resched_rcu_qs();
} else {
/* Deal with stray signal. */
- cond_resched();
- flush_signals(current);
+ cond_resched_rcu_qs();
+ WARN_ON(signal_pending(current));
trace_rcu_grace_period(rsp->name,
ACCESS_ONCE(rsp->gpnum),
TPS("fqswaitsig"));
@@ -1928,7 +1942,7 @@ static void rcu_report_qs_rsp(struct rcu_state *rsp, unsigned long flags)
{
WARN_ON_ONCE(!rcu_gp_in_progress(rsp));
raw_spin_unlock_irqrestore(&rcu_get_root(rsp)->lock, flags);
- wake_up(&rsp->gp_wq); /* Memory barrier implied by wake_up() path. */
+ rcu_gp_kthread_wake(rsp);
}
/*
@@ -2210,8 +2224,6 @@ static void rcu_cleanup_dead_cpu(int cpu, struct rcu_state *rsp)
/* Adjust any no-longer-needed kthreads. */
rcu_boost_kthread_setaffinity(rnp, -1);
- /* Remove the dead CPU from the bitmasks in the rcu_node hierarchy. */
-
/* Exclude any attempts to start a new grace period. */
mutex_lock(&rsp->onoff_mutex);
raw_spin_lock_irqsave(&rsp->orphan_lock, flags);
@@ -2393,8 +2405,8 @@ void rcu_check_callbacks(int cpu, int user)
* at least not while the corresponding CPU is online.
*/
- rcu_sched_qs(cpu);
- rcu_bh_qs(cpu);
+ rcu_sched_qs();
+ rcu_bh_qs();
} else if (!in_softirq()) {
@@ -2405,11 +2417,13 @@ void rcu_check_callbacks(int cpu, int user)
* critical section, so note it.
*/
- rcu_bh_qs(cpu);
+ rcu_bh_qs();
}
rcu_preempt_check_callbacks(cpu);
if (rcu_pending(cpu))
invoke_rcu_core();
+ if (user)
+ rcu_note_voluntary_context_switch(current);
trace_rcu_utilization(TPS("End scheduler-tick"));
}
@@ -2432,7 +2446,7 @@ static void force_qs_rnp(struct rcu_state *rsp,
struct rcu_node *rnp;
rcu_for_each_leaf_node(rsp, rnp) {
- cond_resched();
+ cond_resched_rcu_qs();
mask = 0;
raw_spin_lock_irqsave(&rnp->lock, flags);
smp_mb__after_unlock_lock();
@@ -2449,7 +2463,7 @@ static void force_qs_rnp(struct rcu_state *rsp,
for (; cpu <= rnp->grphi; cpu++, bit <<= 1) {
if ((rnp->qsmask & bit) != 0) {
if ((rnp->qsmaskinit & bit) != 0)
- *isidle = 0;
+ *isidle = false;
if (f(per_cpu_ptr(rsp->rda, cpu), isidle, maxj))
mask |= bit;
}
@@ -2505,9 +2519,10 @@ static void force_quiescent_state(struct rcu_state *rsp)
raw_spin_unlock_irqrestore(&rnp_old->lock, flags);
return; /* Someone beat us to it. */
}
- ACCESS_ONCE(rsp->gp_flags) |= RCU_GP_FLAG_FQS;
+ ACCESS_ONCE(rsp->gp_flags) =
+ ACCESS_ONCE(rsp->gp_flags) | RCU_GP_FLAG_FQS;
raw_spin_unlock_irqrestore(&rnp_old->lock, flags);
- wake_up(&rsp->gp_wq); /* Memory barrier implied by wake_up() path. */
+ rcu_gp_kthread_wake(rsp);
}
/*
@@ -2925,11 +2940,6 @@ static int synchronize_sched_expedited_cpu_stop(void *data)
* restructure your code to batch your updates, and then use a single
* synchronize_sched() instead.
*
- * Note that it is illegal to call this function while holding any lock
- * that is acquired by a CPU-hotplug notifier. And yes, it is also illegal
- * to call this function from a CPU-hotplug notifier. Failing to observe
- * these restriction will result in deadlock.
- *
* This implementation can be thought of as an application of ticket
* locking to RCU, with sync_sched_expedited_started and
* sync_sched_expedited_done taking on the roles of the halves
@@ -2979,7 +2989,12 @@ void synchronize_sched_expedited(void)
*/
snap = atomic_long_inc_return(&rsp->expedited_start);
firstsnap = snap;
- get_online_cpus();
+ if (!try_get_online_cpus()) {
+ /* CPU hotplug operation in flight, fall back to normal GP. */
+ wait_rcu_gp(call_rcu_sched);
+ atomic_long_inc(&rsp->expedited_normal);
+ return;
+ }
WARN_ON_ONCE(cpu_is_offline(raw_smp_processor_id()));
/*
@@ -3026,7 +3041,12 @@ void synchronize_sched_expedited(void)
* and they started after our first try, so their grace
* period works for us.
*/
- get_online_cpus();
+ if (!try_get_online_cpus()) {
+ /* CPU hotplug operation in flight, use normal GP. */
+ wait_rcu_gp(call_rcu_sched);
+ atomic_long_inc(&rsp->expedited_normal);
+ return;
+ }
snap = atomic_long_read(&rsp->expedited_start);
smp_mb(); /* ensure read is before try_stop_cpus(). */
}
@@ -3442,6 +3462,7 @@ static int rcu_cpu_notify(struct notifier_block *self,
case CPU_UP_PREPARE_FROZEN:
rcu_prepare_cpu(cpu);
rcu_prepare_kthreads(cpu);
+ rcu_spawn_all_nocb_kthreads(cpu);
break;
case CPU_ONLINE:
case CPU_DOWN_FAILED:
@@ -3489,7 +3510,7 @@ static int rcu_pm_notify(struct notifier_block *self,
}
/*
- * Spawn the kthread that handles this RCU flavor's grace periods.
+ * Spawn the kthreads that handle each RCU flavor's grace periods.
*/
static int __init rcu_spawn_gp_kthread(void)
{
@@ -3498,6 +3519,7 @@ static int __init rcu_spawn_gp_kthread(void)
struct rcu_state *rsp;
struct task_struct *t;
+ rcu_scheduler_fully_active = 1;
for_each_rcu_flavor(rsp) {
t = kthread_run(rcu_gp_kthread, rsp, "%s", rsp->name);
BUG_ON(IS_ERR(t));
@@ -3505,8 +3527,9 @@ static int __init rcu_spawn_gp_kthread(void)
raw_spin_lock_irqsave(&rnp->lock, flags);
rsp->gp_kthread = t;
raw_spin_unlock_irqrestore(&rnp->lock, flags);
- rcu_spawn_nocb_kthreads(rsp);
}
+ rcu_spawn_nocb_kthreads();
+ rcu_spawn_boost_kthreads();
return 0;
}
early_initcall(rcu_spawn_gp_kthread);
diff --git a/kernel/rcu/tree.h b/kernel/rcu/tree.h
index 71e64c718f75..d03764652d91 100644
--- a/kernel/rcu/tree.h
+++ b/kernel/rcu/tree.h
@@ -350,7 +350,7 @@ struct rcu_data {
int nocb_p_count_lazy; /* (approximate). */
wait_queue_head_t nocb_wq; /* For nocb kthreads to sleep on. */
struct task_struct *nocb_kthread;
- bool nocb_defer_wakeup; /* Defer wakeup of nocb_kthread. */
+ int nocb_defer_wakeup; /* Defer wakeup of nocb_kthread. */
/* The following fields are used by the leader, hence own cacheline. */
struct rcu_head *nocb_gp_head ____cacheline_internodealigned_in_smp;
@@ -358,7 +358,7 @@ struct rcu_data {
struct rcu_head **nocb_gp_tail;
long nocb_gp_count;
long nocb_gp_count_lazy;
- bool nocb_leader_wake; /* Is the nocb leader thread awake? */
+ bool nocb_leader_sleep; /* Is the nocb leader thread asleep? */
struct rcu_data *nocb_next_follower;
/* Next follower in wakeup chain. */
@@ -383,6 +383,11 @@ struct rcu_data {
#define RCU_FORCE_QS 3 /* Need to force quiescent state. */
#define RCU_SIGNAL_INIT RCU_SAVE_DYNTICK
+/* Values for nocb_defer_wakeup field in struct rcu_data. */
+#define RCU_NOGP_WAKE_NOT 0
+#define RCU_NOGP_WAKE 1
+#define RCU_NOGP_WAKE_FORCE 2
+
#define RCU_JIFFIES_TILL_FORCE_QS (1 + (HZ > 250) + (HZ > 500))
/* For jiffies_till_first_fqs and */
/* and jiffies_till_next_fqs. */
@@ -572,6 +577,7 @@ static void rcu_preempt_do_callbacks(void);
static int rcu_spawn_one_boost_kthread(struct rcu_state *rsp,
struct rcu_node *rnp);
#endif /* #ifdef CONFIG_RCU_BOOST */
+static void __init rcu_spawn_boost_kthreads(void);
static void rcu_prepare_kthreads(int cpu);
static void rcu_cleanup_after_idle(int cpu);
static void rcu_prepare_for_idle(int cpu);
@@ -589,10 +595,14 @@ static bool __call_rcu_nocb(struct rcu_data *rdp, struct rcu_head *rhp,
static bool rcu_nocb_adopt_orphan_cbs(struct rcu_state *rsp,
struct rcu_data *rdp,
unsigned long flags);
-static bool rcu_nocb_need_deferred_wakeup(struct rcu_data *rdp);
+static int rcu_nocb_need_deferred_wakeup(struct rcu_data *rdp);
static void do_nocb_deferred_wakeup(struct rcu_data *rdp);
static void rcu_boot_init_nocb_percpu_data(struct rcu_data *rdp);
-static void rcu_spawn_nocb_kthreads(struct rcu_state *rsp);
+static void rcu_spawn_all_nocb_kthreads(int cpu);
+static void __init rcu_spawn_nocb_kthreads(void);
+#ifdef CONFIG_RCU_NOCB_CPU
+static void __init rcu_organize_nocb_kthreads(struct rcu_state *rsp);
+#endif /* #ifdef CONFIG_RCU_NOCB_CPU */
static void __maybe_unused rcu_kick_nohz_cpu(int cpu);
static bool init_nocb_callback_list(struct rcu_data *rdp);
static void rcu_sysidle_enter(struct rcu_dynticks *rdtp, int irq);
@@ -605,6 +615,8 @@ static void rcu_sysidle_report_gp(struct rcu_state *rsp, int isidle,
static void rcu_bind_gp_kthread(void);
static void rcu_sysidle_init_percpu_data(struct rcu_dynticks *rdtp);
static bool rcu_nohz_full_cpu(struct rcu_state *rsp);
+static void rcu_dynticks_task_enter(void);
+static void rcu_dynticks_task_exit(void);
#endif /* #ifndef RCU_TREE_NONCORE */
diff --git a/kernel/rcu/tree_plugin.h b/kernel/rcu/tree_plugin.h
index 00dc411e9676..387dd4599344 100644
--- a/kernel/rcu/tree_plugin.h
+++ b/kernel/rcu/tree_plugin.h
@@ -85,33 +85,6 @@ static void __init rcu_bootup_announce_oddness(void)
pr_info("\tBoot-time adjustment of leaf fanout to %d.\n", rcu_fanout_leaf);
if (nr_cpu_ids != NR_CPUS)
pr_info("\tRCU restricting CPUs from NR_CPUS=%d to nr_cpu_ids=%d.\n", NR_CPUS, nr_cpu_ids);
-#ifdef CONFIG_RCU_NOCB_CPU
-#ifndef CONFIG_RCU_NOCB_CPU_NONE
- if (!have_rcu_nocb_mask) {
- zalloc_cpumask_var(&rcu_nocb_mask, GFP_KERNEL);
- have_rcu_nocb_mask = true;
- }
-#ifdef CONFIG_RCU_NOCB_CPU_ZERO
- pr_info("\tOffload RCU callbacks from CPU 0\n");
- cpumask_set_cpu(0, rcu_nocb_mask);
-#endif /* #ifdef CONFIG_RCU_NOCB_CPU_ZERO */
-#ifdef CONFIG_RCU_NOCB_CPU_ALL
- pr_info("\tOffload RCU callbacks from all CPUs\n");
- cpumask_copy(rcu_nocb_mask, cpu_possible_mask);
-#endif /* #ifdef CONFIG_RCU_NOCB_CPU_ALL */
-#endif /* #ifndef CONFIG_RCU_NOCB_CPU_NONE */
- if (have_rcu_nocb_mask) {
- if (!cpumask_subset(rcu_nocb_mask, cpu_possible_mask)) {
- pr_info("\tNote: kernel parameter 'rcu_nocbs=' contains nonexistent CPUs.\n");
- cpumask_and(rcu_nocb_mask, cpu_possible_mask,
- rcu_nocb_mask);
- }
- cpulist_scnprintf(nocb_buf, sizeof(nocb_buf), rcu_nocb_mask);
- pr_info("\tOffload RCU callbacks from CPUs: %s.\n", nocb_buf);
- if (rcu_nocb_poll)
- pr_info("\tPoll for callbacks from no-CBs CPUs.\n");
- }
-#endif /* #ifdef CONFIG_RCU_NOCB_CPU */
}
#ifdef CONFIG_TREE_PREEMPT_RCU
@@ -134,7 +107,7 @@ static void __init rcu_bootup_announce(void)
* Return the number of RCU-preempt batches processed thus far
* for debug and statistics.
*/
-long rcu_batches_completed_preempt(void)
+static long rcu_batches_completed_preempt(void)
{
return rcu_preempt_state.completed;
}
@@ -155,18 +128,19 @@ EXPORT_SYMBOL_GPL(rcu_batches_completed);
* not in a quiescent state. There might be any number of tasks blocked
* while in an RCU read-side critical section.
*
- * Unlike the other rcu_*_qs() functions, callers to this function
- * must disable irqs in order to protect the assignment to
- * ->rcu_read_unlock_special.
- */
-static void rcu_preempt_qs(int cpu)
-{
- struct rcu_data *rdp = &per_cpu(rcu_preempt_data, cpu);
-
- if (rdp->passed_quiesce == 0)
- trace_rcu_grace_period(TPS("rcu_preempt"), rdp->gpnum, TPS("cpuqs"));
- rdp->passed_quiesce = 1;
- current->rcu_read_unlock_special &= ~RCU_READ_UNLOCK_NEED_QS;
+ * As with the other rcu_*_qs() functions, callers to this function
+ * must disable preemption.
+ */
+static void rcu_preempt_qs(void)
+{
+ if (!__this_cpu_read(rcu_preempt_data.passed_quiesce)) {
+ trace_rcu_grace_period(TPS("rcu_preempt"),
+ __this_cpu_read(rcu_preempt_data.gpnum),
+ TPS("cpuqs"));
+ __this_cpu_write(rcu_preempt_data.passed_quiesce, 1);
+ barrier(); /* Coordinate with rcu_preempt_check_callbacks(). */
+ current->rcu_read_unlock_special.b.need_qs = false;
+ }
}
/*
@@ -190,14 +164,14 @@ static void rcu_preempt_note_context_switch(int cpu)
struct rcu_node *rnp;
if (t->rcu_read_lock_nesting > 0 &&
- (t->rcu_read_unlock_special & RCU_READ_UNLOCK_BLOCKED) == 0) {
+ !t->rcu_read_unlock_special.b.blocked) {
/* Possibly blocking in an RCU read-side critical section. */
rdp = per_cpu_ptr(rcu_preempt_state.rda, cpu);
rnp = rdp->mynode;
raw_spin_lock_irqsave(&rnp->lock, flags);
smp_mb__after_unlock_lock();
- t->rcu_read_unlock_special |= RCU_READ_UNLOCK_BLOCKED;
+ t->rcu_read_unlock_special.b.blocked = true;
t->rcu_blocked_node = rnp;
/*
@@ -239,7 +213,7 @@ static void rcu_preempt_note_context_switch(int cpu)
: rnp->gpnum + 1);
raw_spin_unlock_irqrestore(&rnp->lock, flags);
} else if (t->rcu_read_lock_nesting < 0 &&
- t->rcu_read_unlock_special) {
+ t->rcu_read_unlock_special.s) {
/*
* Complete exit from RCU read-side critical section on
@@ -257,9 +231,7 @@ static void rcu_preempt_note_context_switch(int cpu)
* grace period, then the fact that the task has been enqueued
* means that we continue to block the current grace period.
*/
- local_irq_save(flags);
- rcu_preempt_qs(cpu);
- local_irq_restore(flags);
+ rcu_preempt_qs();
}
/*
@@ -340,7 +312,7 @@ void rcu_read_unlock_special(struct task_struct *t)
bool drop_boost_mutex = false;
#endif /* #ifdef CONFIG_RCU_BOOST */
struct rcu_node *rnp;
- int special;
+ union rcu_special special;
/* NMI handlers cannot block and cannot safely manipulate state. */
if (in_nmi())
@@ -350,12 +322,13 @@ void rcu_read_unlock_special(struct task_struct *t)
/*
* If RCU core is waiting for this CPU to exit critical section,
- * let it know that we have done so.
+ * let it know that we have done so. Because irqs are disabled,
+ * t->rcu_read_unlock_special cannot change.
*/
special = t->rcu_read_unlock_special;
- if (special & RCU_READ_UNLOCK_NEED_QS) {
- rcu_preempt_qs(smp_processor_id());
- if (!t->rcu_read_unlock_special) {
+ if (special.b.need_qs) {
+ rcu_preempt_qs();
+ if (!t->rcu_read_unlock_special.s) {
local_irq_restore(flags);
return;
}
@@ -368,8 +341,8 @@ void rcu_read_unlock_special(struct task_struct *t)
}
/* Clean up if blocked during RCU read-side critical section. */
- if (special & RCU_READ_UNLOCK_BLOCKED) {
- t->rcu_read_unlock_special &= ~RCU_READ_UNLOCK_BLOCKED;
+ if (special.b.blocked) {
+ t->rcu_read_unlock_special.b.blocked = false;
/*
* Remove this task from the list it blocked on. The
@@ -653,12 +626,13 @@ static void rcu_preempt_check_callbacks(int cpu)
struct task_struct *t = current;
if (t->rcu_read_lock_nesting == 0) {
- rcu_preempt_qs(cpu);
+ rcu_preempt_qs();
return;
}
if (t->rcu_read_lock_nesting > 0 &&
- per_cpu(rcu_preempt_data, cpu).qs_pending)
- t->rcu_read_unlock_special |= RCU_READ_UNLOCK_NEED_QS;
+ per_cpu(rcu_preempt_data, cpu).qs_pending &&
+ !per_cpu(rcu_preempt_data, cpu).passed_quiesce)
+ t->rcu_read_unlock_special.b.need_qs = true;
}
#ifdef CONFIG_RCU_BOOST
@@ -819,11 +793,6 @@ sync_rcu_preempt_exp_init(struct rcu_state *rsp, struct rcu_node *rnp)
* 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.
- *
- * Note that it is illegal to call this function while holding any lock
- * that is acquired by a CPU-hotplug notifier. And yes, it is also illegal
- * to call this function from a CPU-hotplug notifier. Failing to observe
- * these restriction will result in deadlock.
*/
void synchronize_rcu_expedited(void)
{
@@ -845,7 +814,11 @@ void synchronize_rcu_expedited(void)
* being boosted. This simplifies the process of moving tasks
* from leaf to root rcu_node structures.
*/
- get_online_cpus();
+ if (!try_get_online_cpus()) {
+ /* CPU-hotplug operation in flight, fall back to normal GP. */
+ wait_rcu_gp(call_rcu);
+ return;
+ }
/*
* Acquire lock, falling back to synchronize_rcu() if too many
@@ -897,7 +870,8 @@ void synchronize_rcu_expedited(void)
/* Clean up and exit. */
smp_mb(); /* ensure expedited GP seen before counter increment. */
- ACCESS_ONCE(sync_rcu_preempt_exp_count)++;
+ ACCESS_ONCE(sync_rcu_preempt_exp_count) =
+ sync_rcu_preempt_exp_count + 1;
unlock_mb_ret:
mutex_unlock(&sync_rcu_preempt_exp_mutex);
mb_ret:
@@ -941,7 +915,7 @@ void exit_rcu(void)
return;
t->rcu_read_lock_nesting = 1;
barrier();
- t->rcu_read_unlock_special = RCU_READ_UNLOCK_BLOCKED;
+ t->rcu_read_unlock_special.b.blocked = true;
__rcu_read_unlock();
}
@@ -1462,14 +1436,13 @@ static struct smp_hotplug_thread rcu_cpu_thread_spec = {
};
/*
- * Spawn all kthreads -- called as soon as the scheduler is running.
+ * Spawn boost kthreads -- called as soon as the scheduler is running.
*/
-static int __init rcu_spawn_kthreads(void)
+static void __init rcu_spawn_boost_kthreads(void)
{
struct rcu_node *rnp;
int cpu;
- rcu_scheduler_fully_active = 1;
for_each_possible_cpu(cpu)
per_cpu(rcu_cpu_has_work, cpu) = 0;
BUG_ON(smpboot_register_percpu_thread(&rcu_cpu_thread_spec));
@@ -1479,9 +1452,7 @@ static int __init rcu_spawn_kthreads(void)
rcu_for_each_leaf_node(rcu_state_p, rnp)
(void)rcu_spawn_one_boost_kthread(rcu_state_p, rnp);
}
- return 0;
}
-early_initcall(rcu_spawn_kthreads);
static void rcu_prepare_kthreads(int cpu)
{
@@ -1519,12 +1490,9 @@ static void rcu_boost_kthread_setaffinity(struct rcu_node *rnp, int outgoingcpu)
{
}
-static int __init rcu_scheduler_really_started(void)
+static void __init rcu_spawn_boost_kthreads(void)
{
- rcu_scheduler_fully_active = 1;
- return 0;
}
-early_initcall(rcu_scheduler_really_started);
static void rcu_prepare_kthreads(int cpu)
{
@@ -1625,7 +1593,7 @@ static bool __maybe_unused rcu_try_advance_all_cbs(void)
/* Exit early if we advanced recently. */
if (jiffies == rdtp->last_advance_all)
- return 0;
+ return false;
rdtp->last_advance_all = jiffies;
for_each_rcu_flavor(rsp) {
@@ -1848,7 +1816,7 @@ static int rcu_oom_notify(struct notifier_block *self,
get_online_cpus();
for_each_online_cpu(cpu) {
smp_call_function_single(cpu, rcu_oom_notify_cpu, NULL, 1);
- cond_resched();
+ cond_resched_rcu_qs();
}
put_online_cpus();
@@ -2074,9 +2042,9 @@ static void wake_nocb_leader(struct rcu_data *rdp, bool force)
if (!ACCESS_ONCE(rdp_leader->nocb_kthread))
return;
- if (!ACCESS_ONCE(rdp_leader->nocb_leader_wake) || force) {
- /* Prior xchg orders against prior callback enqueue. */
- ACCESS_ONCE(rdp_leader->nocb_leader_wake) = true;
+ if (ACCESS_ONCE(rdp_leader->nocb_leader_sleep) || force) {
+ /* Prior smp_mb__after_atomic() orders against prior enqueue. */
+ ACCESS_ONCE(rdp_leader->nocb_leader_sleep) = false;
wake_up(&rdp_leader->nocb_wq);
}
}
@@ -2104,6 +2072,7 @@ static void __call_rcu_nocb_enqueue(struct rcu_data *rdp,
ACCESS_ONCE(*old_rhpp) = rhp;
atomic_long_add(rhcount, &rdp->nocb_q_count);
atomic_long_add(rhcount_lazy, &rdp->nocb_q_count_lazy);
+ smp_mb__after_atomic(); /* Store *old_rhpp before _wake test. */
/* If we are not being polled and there is a kthread, awaken it ... */
t = ACCESS_ONCE(rdp->nocb_kthread);
@@ -2120,16 +2089,23 @@ static void __call_rcu_nocb_enqueue(struct rcu_data *rdp,
trace_rcu_nocb_wake(rdp->rsp->name, rdp->cpu,
TPS("WakeEmpty"));
} else {
- rdp->nocb_defer_wakeup = true;
+ rdp->nocb_defer_wakeup = RCU_NOGP_WAKE;
trace_rcu_nocb_wake(rdp->rsp->name, rdp->cpu,
TPS("WakeEmptyIsDeferred"));
}
rdp->qlen_last_fqs_check = 0;
} else if (len > rdp->qlen_last_fqs_check + qhimark) {
/* ... or if many callbacks queued. */
- wake_nocb_leader(rdp, true);
+ if (!irqs_disabled_flags(flags)) {
+ wake_nocb_leader(rdp, true);
+ trace_rcu_nocb_wake(rdp->rsp->name, rdp->cpu,
+ TPS("WakeOvf"));
+ } else {
+ rdp->nocb_defer_wakeup = RCU_NOGP_WAKE_FORCE;
+ trace_rcu_nocb_wake(rdp->rsp->name, rdp->cpu,
+ TPS("WakeOvfIsDeferred"));
+ }
rdp->qlen_last_fqs_check = LONG_MAX / 2;
- trace_rcu_nocb_wake(rdp->rsp->name, rdp->cpu, TPS("WakeOvf"));
} else {
trace_rcu_nocb_wake(rdp->rsp->name, rdp->cpu, TPS("WakeNot"));
}
@@ -2150,7 +2126,7 @@ static bool __call_rcu_nocb(struct rcu_data *rdp, struct rcu_head *rhp,
{
if (!rcu_is_nocb_cpu(rdp->cpu))
- return 0;
+ return false;
__call_rcu_nocb_enqueue(rdp, rhp, &rhp->next, 1, lazy, flags);
if (__is_kfree_rcu_offset((unsigned long)rhp->func))
trace_rcu_kfree_callback(rdp->rsp->name, rhp,
@@ -2161,7 +2137,18 @@ static bool __call_rcu_nocb(struct rcu_data *rdp, struct rcu_head *rhp,
trace_rcu_callback(rdp->rsp->name, rhp,
-atomic_long_read(&rdp->nocb_q_count_lazy),
-atomic_long_read(&rdp->nocb_q_count));
- return 1;
+
+ /*
+ * If called from an extended quiescent state with interrupts
+ * disabled, invoke the RCU core in order to allow the idle-entry
+ * deferred-wakeup check to function.
+ */
+ if (irqs_disabled_flags(flags) &&
+ !rcu_is_watching() &&
+ cpu_online(smp_processor_id()))
+ invoke_rcu_core();
+
+ return true;
}
/*
@@ -2177,7 +2164,7 @@ static bool __maybe_unused rcu_nocb_adopt_orphan_cbs(struct rcu_state *rsp,
/* If this is not a no-CBs CPU, tell the caller to do it the old way. */
if (!rcu_is_nocb_cpu(smp_processor_id()))
- return 0;
+ return false;
rsp->qlen = 0;
rsp->qlen_lazy = 0;
@@ -2196,7 +2183,7 @@ static bool __maybe_unused rcu_nocb_adopt_orphan_cbs(struct rcu_state *rsp,
rsp->orphan_nxtlist = NULL;
rsp->orphan_nxttail = &rsp->orphan_nxtlist;
}
- return 1;
+ return true;
}
/*
@@ -2229,7 +2216,7 @@ static void rcu_nocb_wait_gp(struct rcu_data *rdp)
(d = ULONG_CMP_GE(ACCESS_ONCE(rnp->completed), c)));
if (likely(d))
break;
- flush_signals(current);
+ WARN_ON(signal_pending(current));
trace_rcu_future_gp(rnp, rdp, c, TPS("ResumeWait"));
}
trace_rcu_future_gp(rnp, rdp, c, TPS("EndWait"));
@@ -2253,7 +2240,7 @@ wait_again:
if (!rcu_nocb_poll) {
trace_rcu_nocb_wake(my_rdp->rsp->name, my_rdp->cpu, "Sleep");
wait_event_interruptible(my_rdp->nocb_wq,
- ACCESS_ONCE(my_rdp->nocb_leader_wake));
+ !ACCESS_ONCE(my_rdp->nocb_leader_sleep));
/* Memory barrier handled by smp_mb() calls below and repoll. */
} else if (firsttime) {
firsttime = false; /* Don't drown trace log with "Poll"! */
@@ -2288,16 +2275,16 @@ wait_again:
if (!rcu_nocb_poll)
trace_rcu_nocb_wake(my_rdp->rsp->name, my_rdp->cpu,
"WokeEmpty");
- flush_signals(current);
+ WARN_ON(signal_pending(current));
schedule_timeout_interruptible(1);
/* Rescan in case we were a victim of memory ordering. */
- my_rdp->nocb_leader_wake = false;
- smp_mb(); /* Ensure _wake false before scan. */
+ my_rdp->nocb_leader_sleep = true;
+ smp_mb(); /* Ensure _sleep true before scan. */
for (rdp = my_rdp; rdp; rdp = rdp->nocb_next_follower)
if (ACCESS_ONCE(rdp->nocb_head)) {
/* Found CB, so short-circuit next wait. */
- my_rdp->nocb_leader_wake = true;
+ my_rdp->nocb_leader_sleep = false;
break;
}
goto wait_again;
@@ -2307,17 +2294,17 @@ wait_again:
rcu_nocb_wait_gp(my_rdp);
/*
- * We left ->nocb_leader_wake set to reduce cache thrashing.
- * We clear it now, but recheck for new callbacks while
+ * We left ->nocb_leader_sleep unset to reduce cache thrashing.
+ * We set it now, but recheck for new callbacks while
* traversing our follower list.
*/
- my_rdp->nocb_leader_wake = false;
- smp_mb(); /* Ensure _wake false before scan of ->nocb_head. */
+ my_rdp->nocb_leader_sleep = true;
+ smp_mb(); /* Ensure _sleep true before scan of ->nocb_head. */
/* Each pass through the following loop wakes a follower, if needed. */
for (rdp = my_rdp; rdp; rdp = rdp->nocb_next_follower) {
if (ACCESS_ONCE(rdp->nocb_head))
- my_rdp->nocb_leader_wake = true; /* No need to wait. */
+ my_rdp->nocb_leader_sleep = false;/* No need to sleep.*/
if (!rdp->nocb_gp_head)
continue; /* No CBs, so no need to wake follower. */
@@ -2327,6 +2314,7 @@ wait_again:
atomic_long_add(rdp->nocb_gp_count, &rdp->nocb_follower_count);
atomic_long_add(rdp->nocb_gp_count_lazy,
&rdp->nocb_follower_count_lazy);
+ smp_mb__after_atomic(); /* Store *tail before wakeup. */
if (rdp != my_rdp && tail == &rdp->nocb_follower_head) {
/*
* List was empty, wake up the follower.
@@ -2367,7 +2355,7 @@ static void nocb_follower_wait(struct rcu_data *rdp)
if (!rcu_nocb_poll)
trace_rcu_nocb_wake(rdp->rsp->name, rdp->cpu,
"WokeEmpty");
- flush_signals(current);
+ WARN_ON(signal_pending(current));
schedule_timeout_interruptible(1);
}
}
@@ -2428,15 +2416,16 @@ static int rcu_nocb_kthread(void *arg)
list = next;
}
trace_rcu_batch_end(rdp->rsp->name, c, !!list, 0, 0, 1);
- ACCESS_ONCE(rdp->nocb_p_count) -= c;
- ACCESS_ONCE(rdp->nocb_p_count_lazy) -= cl;
+ ACCESS_ONCE(rdp->nocb_p_count) = rdp->nocb_p_count - c;
+ ACCESS_ONCE(rdp->nocb_p_count_lazy) =
+ rdp->nocb_p_count_lazy - cl;
rdp->n_nocbs_invoked += c;
}
return 0;
}
/* Is a deferred wakeup of rcu_nocb_kthread() required? */
-static bool rcu_nocb_need_deferred_wakeup(struct rcu_data *rdp)
+static int rcu_nocb_need_deferred_wakeup(struct rcu_data *rdp)
{
return ACCESS_ONCE(rdp->nocb_defer_wakeup);
}
@@ -2444,11 +2433,79 @@ static bool rcu_nocb_need_deferred_wakeup(struct rcu_data *rdp)
/* Do a deferred wakeup of rcu_nocb_kthread(). */
static void do_nocb_deferred_wakeup(struct rcu_data *rdp)
{
+ int ndw;
+
if (!rcu_nocb_need_deferred_wakeup(rdp))
return;
- ACCESS_ONCE(rdp->nocb_defer_wakeup) = false;
- wake_nocb_leader(rdp, false);
- trace_rcu_nocb_wake(rdp->rsp->name, rdp->cpu, TPS("DeferredWakeEmpty"));
+ ndw = ACCESS_ONCE(rdp->nocb_defer_wakeup);
+ ACCESS_ONCE(rdp->nocb_defer_wakeup) = RCU_NOGP_WAKE_NOT;
+ wake_nocb_leader(rdp, ndw == RCU_NOGP_WAKE_FORCE);
+ trace_rcu_nocb_wake(rdp->rsp->name, rdp->cpu, TPS("DeferredWake"));
+}
+
+void __init rcu_init_nohz(void)
+{
+ int cpu;
+ bool need_rcu_nocb_mask = true;
+ struct rcu_state *rsp;
+
+#ifdef CONFIG_RCU_NOCB_CPU_NONE
+ need_rcu_nocb_mask = false;
+#endif /* #ifndef CONFIG_RCU_NOCB_CPU_NONE */
+
+#if defined(CONFIG_NO_HZ_FULL)
+ if (tick_nohz_full_running && cpumask_weight(tick_nohz_full_mask))
+ need_rcu_nocb_mask = true;
+#endif /* #if defined(CONFIG_NO_HZ_FULL) */
+
+ if (!have_rcu_nocb_mask && need_rcu_nocb_mask) {
+ if (!zalloc_cpumask_var(&rcu_nocb_mask, GFP_KERNEL)) {
+ pr_info("rcu_nocb_mask allocation failed, callback offloading disabled.\n");
+ return;
+ }
+ have_rcu_nocb_mask = true;
+ }
+ if (!have_rcu_nocb_mask)
+ return;
+
+#ifdef CONFIG_RCU_NOCB_CPU_ZERO
+ pr_info("\tOffload RCU callbacks from CPU 0\n");
+ cpumask_set_cpu(0, rcu_nocb_mask);
+#endif /* #ifdef CONFIG_RCU_NOCB_CPU_ZERO */
+#ifdef CONFIG_RCU_NOCB_CPU_ALL
+ pr_info("\tOffload RCU callbacks from all CPUs\n");
+ cpumask_copy(rcu_nocb_mask, cpu_possible_mask);
+#endif /* #ifdef CONFIG_RCU_NOCB_CPU_ALL */
+#if defined(CONFIG_NO_HZ_FULL)
+ if (tick_nohz_full_running)
+ cpumask_or(rcu_nocb_mask, rcu_nocb_mask, tick_nohz_full_mask);
+#endif /* #if defined(CONFIG_NO_HZ_FULL) */
+
+ if (!cpumask_subset(rcu_nocb_mask, cpu_possible_mask)) {
+ pr_info("\tNote: kernel parameter 'rcu_nocbs=' contains nonexistent CPUs.\n");
+ cpumask_and(rcu_nocb_mask, cpu_possible_mask,
+ rcu_nocb_mask);
+ }
+ cpulist_scnprintf(nocb_buf, sizeof(nocb_buf), rcu_nocb_mask);
+ pr_info("\tOffload RCU callbacks from CPUs: %s.\n", nocb_buf);
+ if (rcu_nocb_poll)
+ pr_info("\tPoll for callbacks from no-CBs CPUs.\n");
+
+ for_each_rcu_flavor(rsp) {
+ for_each_cpu(cpu, rcu_nocb_mask) {
+ struct rcu_data *rdp = per_cpu_ptr(rsp->rda, cpu);
+
+ /*
+ * If there are early callbacks, they will need
+ * to be moved to the nocb lists.
+ */
+ WARN_ON_ONCE(rdp->nxttail[RCU_NEXT_TAIL] !=
+ &rdp->nxtlist &&
+ rdp->nxttail[RCU_NEXT_TAIL] != NULL);
+ init_nocb_callback_list(rdp);
+ }
+ rcu_organize_nocb_kthreads(rsp);
+ }
}
/* Initialize per-rcu_data variables for no-CBs CPUs. */
@@ -2459,15 +2516,85 @@ static void __init rcu_boot_init_nocb_percpu_data(struct rcu_data *rdp)
rdp->nocb_follower_tail = &rdp->nocb_follower_head;
}
+/*
+ * If the specified CPU is a no-CBs CPU that does not already have its
+ * rcuo kthread for the specified RCU flavor, spawn it. If the CPUs are
+ * brought online out of order, this can require re-organizing the
+ * leader-follower relationships.
+ */
+static void rcu_spawn_one_nocb_kthread(struct rcu_state *rsp, int cpu)
+{
+ struct rcu_data *rdp;
+ struct rcu_data *rdp_last;
+ struct rcu_data *rdp_old_leader;
+ struct rcu_data *rdp_spawn = per_cpu_ptr(rsp->rda, cpu);
+ struct task_struct *t;
+
+ /*
+ * If this isn't a no-CBs CPU or if it already has an rcuo kthread,
+ * then nothing to do.
+ */
+ if (!rcu_is_nocb_cpu(cpu) || rdp_spawn->nocb_kthread)
+ return;
+
+ /* If we didn't spawn the leader first, reorganize! */
+ rdp_old_leader = rdp_spawn->nocb_leader;
+ if (rdp_old_leader != rdp_spawn && !rdp_old_leader->nocb_kthread) {
+ rdp_last = NULL;
+ rdp = rdp_old_leader;
+ do {
+ rdp->nocb_leader = rdp_spawn;
+ if (rdp_last && rdp != rdp_spawn)
+ rdp_last->nocb_next_follower = rdp;
+ rdp_last = rdp;
+ rdp = rdp->nocb_next_follower;
+ rdp_last->nocb_next_follower = NULL;
+ } while (rdp);
+ rdp_spawn->nocb_next_follower = rdp_old_leader;
+ }
+
+ /* Spawn the kthread for this CPU and RCU flavor. */
+ t = kthread_run(rcu_nocb_kthread, rdp_spawn,
+ "rcuo%c/%d", rsp->abbr, cpu);
+ BUG_ON(IS_ERR(t));
+ ACCESS_ONCE(rdp_spawn->nocb_kthread) = t;
+}
+
+/*
+ * If the specified CPU is a no-CBs CPU that does not already have its
+ * rcuo kthreads, spawn them.
+ */
+static void rcu_spawn_all_nocb_kthreads(int cpu)
+{
+ struct rcu_state *rsp;
+
+ if (rcu_scheduler_fully_active)
+ for_each_rcu_flavor(rsp)
+ rcu_spawn_one_nocb_kthread(rsp, cpu);
+}
+
+/*
+ * Once the scheduler is running, spawn rcuo kthreads for all online
+ * no-CBs CPUs. This assumes that the early_initcall()s happen before
+ * non-boot CPUs come online -- if this changes, we will need to add
+ * some mutual exclusion.
+ */
+static void __init rcu_spawn_nocb_kthreads(void)
+{
+ int cpu;
+
+ for_each_online_cpu(cpu)
+ rcu_spawn_all_nocb_kthreads(cpu);
+}
+
/* How many follower CPU IDs per leader? Default of -1 for sqrt(nr_cpu_ids). */
static int rcu_nocb_leader_stride = -1;
module_param(rcu_nocb_leader_stride, int, 0444);
/*
- * Create a kthread for each RCU flavor for each no-CBs CPU.
- * Also initialize leader-follower relationships.
+ * Initialize leader-follower relationships for all no-CBs CPU.
*/
-static void __init rcu_spawn_nocb_kthreads(struct rcu_state *rsp)
+static void __init rcu_organize_nocb_kthreads(struct rcu_state *rsp)
{
int cpu;
int ls = rcu_nocb_leader_stride;
@@ -2475,14 +2602,9 @@ static void __init rcu_spawn_nocb_kthreads(struct rcu_state *rsp)
struct rcu_data *rdp;
struct rcu_data *rdp_leader = NULL; /* Suppress misguided gcc warn. */
struct rcu_data *rdp_prev = NULL;
- struct task_struct *t;
- if (rcu_nocb_mask == NULL)
+ if (!have_rcu_nocb_mask)
return;
-#if defined(CONFIG_NO_HZ_FULL) && !defined(CONFIG_NO_HZ_FULL_ALL)
- if (tick_nohz_full_running)
- cpumask_or(rcu_nocb_mask, rcu_nocb_mask, tick_nohz_full_mask);
-#endif /* #if defined(CONFIG_NO_HZ_FULL) && !defined(CONFIG_NO_HZ_FULL_ALL) */
if (ls == -1) {
ls = int_sqrt(nr_cpu_ids);
rcu_nocb_leader_stride = ls;
@@ -2505,21 +2627,15 @@ static void __init rcu_spawn_nocb_kthreads(struct rcu_state *rsp)
rdp_prev->nocb_next_follower = rdp;
}
rdp_prev = rdp;
-
- /* Spawn the kthread for this CPU. */
- t = kthread_run(rcu_nocb_kthread, rdp,
- "rcuo%c/%d", rsp->abbr, cpu);
- BUG_ON(IS_ERR(t));
- ACCESS_ONCE(rdp->nocb_kthread) = t;
}
}
/* Prevent __call_rcu() from enqueuing callbacks on no-CBs CPUs */
static bool init_nocb_callback_list(struct rcu_data *rdp)
{
- if (rcu_nocb_mask == NULL ||
- !cpumask_test_cpu(rdp->cpu, rcu_nocb_mask))
+ if (!rcu_is_nocb_cpu(rdp->cpu))
return false;
+
rdp->nxttail[RCU_NEXT_TAIL] = NULL;
return true;
}
@@ -2541,21 +2657,21 @@ static void rcu_init_one_nocb(struct rcu_node *rnp)
static bool __call_rcu_nocb(struct rcu_data *rdp, struct rcu_head *rhp,
bool lazy, unsigned long flags)
{
- return 0;
+ return false;
}
static bool __maybe_unused rcu_nocb_adopt_orphan_cbs(struct rcu_state *rsp,
struct rcu_data *rdp,
unsigned long flags)
{
- return 0;
+ return false;
}
static void __init rcu_boot_init_nocb_percpu_data(struct rcu_data *rdp)
{
}
-static bool rcu_nocb_need_deferred_wakeup(struct rcu_data *rdp)
+static int rcu_nocb_need_deferred_wakeup(struct rcu_data *rdp)
{
return false;
}
@@ -2564,7 +2680,11 @@ static void do_nocb_deferred_wakeup(struct rcu_data *rdp)
{
}
-static void __init rcu_spawn_nocb_kthreads(struct rcu_state *rsp)
+static void rcu_spawn_all_nocb_kthreads(int cpu)
+{
+}
+
+static void __init rcu_spawn_nocb_kthreads(void)
{
}
@@ -2595,16 +2715,6 @@ static void __maybe_unused rcu_kick_nohz_cpu(int cpu)
#ifdef CONFIG_NO_HZ_FULL_SYSIDLE
-/*
- * Define RCU flavor that holds sysidle state. This needs to be the
- * most active flavor of RCU.
- */
-#ifdef CONFIG_PREEMPT_RCU
-static struct rcu_state *rcu_sysidle_state = &rcu_preempt_state;
-#else /* #ifdef CONFIG_PREEMPT_RCU */
-static struct rcu_state *rcu_sysidle_state = &rcu_sched_state;
-#endif /* #else #ifdef CONFIG_PREEMPT_RCU */
-
static int full_sysidle_state; /* Current system-idle state. */
#define RCU_SYSIDLE_NOT 0 /* Some CPU is not idle. */
#define RCU_SYSIDLE_SHORT 1 /* All CPUs idle for brief period. */
@@ -2622,6 +2732,10 @@ static void rcu_sysidle_enter(struct rcu_dynticks *rdtp, int irq)
{
unsigned long j;
+ /* If there are no nohz_full= CPUs, no need to track this. */
+ if (!tick_nohz_full_enabled())
+ return;
+
/* Adjust nesting, check for fully idle. */
if (irq) {
rdtp->dynticks_idle_nesting--;
@@ -2687,6 +2801,10 @@ void rcu_sysidle_force_exit(void)
*/
static void rcu_sysidle_exit(struct rcu_dynticks *rdtp, int irq)
{
+ /* If there are no nohz_full= CPUs, no need to track this. */
+ if (!tick_nohz_full_enabled())
+ return;
+
/* Adjust nesting, check for already non-idle. */
if (irq) {
rdtp->dynticks_idle_nesting++;
@@ -2741,12 +2859,16 @@ static void rcu_sysidle_check_cpu(struct rcu_data *rdp, bool *isidle,
unsigned long j;
struct rcu_dynticks *rdtp = rdp->dynticks;
+ /* If there are no nohz_full= CPUs, don't check system-wide idleness. */
+ if (!tick_nohz_full_enabled())
+ return;
+
/*
* If some other CPU has already reported non-idle, if this is
* not the flavor of RCU that tracks sysidle state, or if this
* is an offline or the timekeeping CPU, nothing to do.
*/
- if (!*isidle || rdp->rsp != rcu_sysidle_state ||
+ if (!*isidle || rdp->rsp != rcu_state_p ||
cpu_is_offline(rdp->cpu) || rdp->cpu == tick_do_timer_cpu)
return;
if (rcu_gp_in_progress(rdp->rsp))
@@ -2772,7 +2894,7 @@ static void rcu_sysidle_check_cpu(struct rcu_data *rdp, bool *isidle,
*/
static bool is_sysidle_rcu_state(struct rcu_state *rsp)
{
- return rsp == rcu_sysidle_state;
+ return rsp == rcu_state_p;
}
/*
@@ -2850,7 +2972,7 @@ static void rcu_sysidle_cancel(void)
static void rcu_sysidle_report(struct rcu_state *rsp, int isidle,
unsigned long maxj, bool gpkt)
{
- if (rsp != rcu_sysidle_state)
+ if (rsp != rcu_state_p)
return; /* Wrong flavor, ignore. */
if (gpkt && nr_cpu_ids <= CONFIG_NO_HZ_FULL_SYSIDLE_SMALL)
return; /* Running state machine from timekeeping CPU. */
@@ -2867,6 +2989,10 @@ static void rcu_sysidle_report(struct rcu_state *rsp, int isidle,
static void rcu_sysidle_report_gp(struct rcu_state *rsp, int isidle,
unsigned long maxj)
{
+ /* If there are no nohz_full= CPUs, no need to track this. */
+ if (!tick_nohz_full_enabled())
+ return;
+
rcu_sysidle_report(rsp, isidle, maxj, true);
}
@@ -2893,7 +3019,8 @@ static void rcu_sysidle_cb(struct rcu_head *rhp)
/*
* Check to see if the system is fully idle, other than the timekeeping CPU.
- * The caller must have disabled interrupts.
+ * The caller must have disabled interrupts. This is not intended to be
+ * called unless tick_nohz_full_enabled().
*/
bool rcu_sys_is_idle(void)
{
@@ -2919,13 +3046,12 @@ bool rcu_sys_is_idle(void)
/* Scan all the CPUs looking for nonidle CPUs. */
for_each_possible_cpu(cpu) {
- rdp = per_cpu_ptr(rcu_sysidle_state->rda, cpu);
+ rdp = per_cpu_ptr(rcu_state_p->rda, cpu);
rcu_sysidle_check_cpu(rdp, &isidle, &maxj);
if (!isidle)
break;
}
- rcu_sysidle_report(rcu_sysidle_state,
- isidle, maxj, false);
+ rcu_sysidle_report(rcu_state_p, isidle, maxj, false);
oldrss = rss;
rss = ACCESS_ONCE(full_sysidle_state);
}
@@ -2952,7 +3078,7 @@ bool rcu_sys_is_idle(void)
* provided by the memory allocator.
*/
if (nr_cpu_ids > CONFIG_NO_HZ_FULL_SYSIDLE_SMALL &&
- !rcu_gp_in_progress(rcu_sysidle_state) &&
+ !rcu_gp_in_progress(rcu_state_p) &&
!rsh.inuse && xchg(&rsh.inuse, 1) == 0)
call_rcu(&rsh.rh, rcu_sysidle_cb);
return false;
@@ -3036,3 +3162,19 @@ static void rcu_bind_gp_kthread(void)
housekeeping_affine(current);
#endif /* #else #ifdef CONFIG_NO_HZ_FULL_SYSIDLE */
}
+
+/* Record the current task on dyntick-idle entry. */
+static void rcu_dynticks_task_enter(void)
+{
+#if defined(CONFIG_TASKS_RCU) && defined(CONFIG_NO_HZ_FULL)
+ ACCESS_ONCE(current->rcu_tasks_idle_cpu) = smp_processor_id();
+#endif /* #if defined(CONFIG_TASKS_RCU) && defined(CONFIG_NO_HZ_FULL) */
+}
+
+/* Record no current task on dyntick-idle exit. */
+static void rcu_dynticks_task_exit(void)
+{
+#if defined(CONFIG_TASKS_RCU) && defined(CONFIG_NO_HZ_FULL)
+ ACCESS_ONCE(current->rcu_tasks_idle_cpu) = -1;
+#endif /* #if defined(CONFIG_TASKS_RCU) && defined(CONFIG_NO_HZ_FULL) */
+}
diff --git a/kernel/rcu/update.c b/kernel/rcu/update.c
index 4056d7992a6c..3ef8ba58694e 100644
--- a/kernel/rcu/update.c
+++ b/kernel/rcu/update.c
@@ -47,6 +47,8 @@
#include <linux/hardirq.h>
#include <linux/delay.h>
#include <linux/module.h>
+#include <linux/kthread.h>
+#include <linux/tick.h>
#define CREATE_TRACE_POINTS
@@ -91,7 +93,7 @@ void __rcu_read_unlock(void)
barrier(); /* critical section before exit code. */
t->rcu_read_lock_nesting = INT_MIN;
barrier(); /* assign before ->rcu_read_unlock_special load */
- if (unlikely(ACCESS_ONCE(t->rcu_read_unlock_special)))
+ if (unlikely(ACCESS_ONCE(t->rcu_read_unlock_special.s)))
rcu_read_unlock_special(t);
barrier(); /* ->rcu_read_unlock_special load before assign */
t->rcu_read_lock_nesting = 0;
@@ -137,6 +139,38 @@ int notrace debug_lockdep_rcu_enabled(void)
EXPORT_SYMBOL_GPL(debug_lockdep_rcu_enabled);
/**
+ * rcu_read_lock_held() - might we be in RCU read-side critical section?
+ *
+ * If CONFIG_DEBUG_LOCK_ALLOC is selected, returns nonzero iff in an RCU
+ * read-side critical section. In absence of CONFIG_DEBUG_LOCK_ALLOC,
+ * this assumes we are in an RCU read-side critical section unless it can
+ * prove otherwise. This is useful for debug checks in functions that
+ * require that they be called within an RCU read-side critical section.
+ *
+ * Checks debug_lockdep_rcu_enabled() to prevent false positives during boot
+ * and while lockdep is disabled.
+ *
+ * Note that rcu_read_lock() and the matching rcu_read_unlock() must
+ * occur in the same context, for example, it is illegal to invoke
+ * rcu_read_unlock() in process context if the matching rcu_read_lock()
+ * was invoked from within an irq handler.
+ *
+ * Note that rcu_read_lock() is disallowed if the CPU is either idle or
+ * offline from an RCU perspective, so check for those as well.
+ */
+int rcu_read_lock_held(void)
+{
+ if (!debug_lockdep_rcu_enabled())
+ return 1;
+ if (!rcu_is_watching())
+ return 0;
+ if (!rcu_lockdep_current_cpu_online())
+ return 0;
+ return lock_is_held(&rcu_lock_map);
+}
+EXPORT_SYMBOL_GPL(rcu_read_lock_held);
+
+/**
* rcu_read_lock_bh_held() - might we be in RCU-bh read-side critical section?
*
* Check for bottom half being disabled, which covers both the
@@ -347,3 +381,312 @@ static int __init check_cpu_stall_init(void)
early_initcall(check_cpu_stall_init);
#endif /* #ifdef CONFIG_RCU_STALL_COMMON */
+
+#ifdef CONFIG_TASKS_RCU
+
+/*
+ * Simple variant of RCU whose quiescent states are voluntary context switch,
+ * user-space execution, and idle. As such, grace periods can take one good
+ * long time. There are no read-side primitives similar to rcu_read_lock()
+ * and rcu_read_unlock() because this implementation is intended to get
+ * the system into a safe state for some of the manipulations involved in
+ * tracing and the like. Finally, this implementation does not support
+ * high call_rcu_tasks() rates from multiple CPUs. If this is required,
+ * per-CPU callback lists will be needed.
+ */
+
+/* Global list of callbacks and associated lock. */
+static struct rcu_head *rcu_tasks_cbs_head;
+static struct rcu_head **rcu_tasks_cbs_tail = &rcu_tasks_cbs_head;
+static DECLARE_WAIT_QUEUE_HEAD(rcu_tasks_cbs_wq);
+static DEFINE_RAW_SPINLOCK(rcu_tasks_cbs_lock);
+
+/* Track exiting tasks in order to allow them to be waited for. */
+DEFINE_SRCU(tasks_rcu_exit_srcu);
+
+/* Control stall timeouts. Disable with <= 0, otherwise jiffies till stall. */
+static int rcu_task_stall_timeout __read_mostly = HZ * 60 * 10;
+module_param(rcu_task_stall_timeout, int, 0644);
+
+static void rcu_spawn_tasks_kthread(void);
+
+/*
+ * Post an RCU-tasks callback. First call must be from process context
+ * after the scheduler if fully operational.
+ */
+void call_rcu_tasks(struct rcu_head *rhp, void (*func)(struct rcu_head *rhp))
+{
+ unsigned long flags;
+ bool needwake;
+
+ rhp->next = NULL;
+ rhp->func = func;
+ raw_spin_lock_irqsave(&rcu_tasks_cbs_lock, flags);
+ needwake = !rcu_tasks_cbs_head;
+ *rcu_tasks_cbs_tail = rhp;
+ rcu_tasks_cbs_tail = &rhp->next;
+ raw_spin_unlock_irqrestore(&rcu_tasks_cbs_lock, flags);
+ if (needwake) {
+ rcu_spawn_tasks_kthread();
+ wake_up(&rcu_tasks_cbs_wq);
+ }
+}
+EXPORT_SYMBOL_GPL(call_rcu_tasks);
+
+/**
+ * synchronize_rcu_tasks - wait until an rcu-tasks grace period has elapsed.
+ *
+ * Control will return to the caller some time after a full rcu-tasks
+ * grace period has elapsed, in other words after all currently
+ * executing rcu-tasks read-side critical sections have elapsed. These
+ * read-side critical sections are delimited by calls to schedule(),
+ * cond_resched_rcu_qs(), idle execution, userspace execution, calls
+ * to synchronize_rcu_tasks(), and (in theory, anyway) cond_resched().
+ *
+ * This is a very specialized primitive, intended only for a few uses in
+ * tracing and other situations requiring manipulation of function
+ * preambles and profiling hooks. The synchronize_rcu_tasks() function
+ * is not (yet) intended for heavy use from multiple CPUs.
+ *
+ * Note that this guarantee implies further memory-ordering guarantees.
+ * On systems with more than one CPU, when synchronize_rcu_tasks() returns,
+ * each CPU is guaranteed to have executed a full memory barrier since the
+ * end of its last RCU-tasks read-side critical section whose beginning
+ * preceded the call to synchronize_rcu_tasks(). In addition, each CPU
+ * having an RCU-tasks read-side critical section that extends beyond
+ * the return from synchronize_rcu_tasks() is guaranteed to have executed
+ * a full memory barrier after the beginning of synchronize_rcu_tasks()
+ * and before the beginning of that RCU-tasks read-side critical section.
+ * Note that these guarantees include CPUs that are offline, idle, or
+ * executing in user mode, as well as CPUs that are executing in the kernel.
+ *
+ * Furthermore, if CPU A invoked synchronize_rcu_tasks(), which returned
+ * to its caller on CPU B, then both CPU A and CPU B are guaranteed
+ * to have executed a full memory barrier during the execution of
+ * synchronize_rcu_tasks() -- even if CPU A and CPU B are the same CPU
+ * (but again only if the system has more than one CPU).
+ */
+void synchronize_rcu_tasks(void)
+{
+ /* Complain if the scheduler has not started. */
+ rcu_lockdep_assert(!rcu_scheduler_active,
+ "synchronize_rcu_tasks called too soon");
+
+ /* Wait for the grace period. */
+ wait_rcu_gp(call_rcu_tasks);
+}
+EXPORT_SYMBOL_GPL(synchronize_rcu_tasks);
+
+/**
+ * rcu_barrier_tasks - Wait for in-flight call_rcu_tasks() callbacks.
+ *
+ * Although the current implementation is guaranteed to wait, it is not
+ * obligated to, for example, if there are no pending callbacks.
+ */
+void rcu_barrier_tasks(void)
+{
+ /* There is only one callback queue, so this is easy. ;-) */
+ synchronize_rcu_tasks();
+}
+EXPORT_SYMBOL_GPL(rcu_barrier_tasks);
+
+/* See if tasks are still holding out, complain if so. */
+static void check_holdout_task(struct task_struct *t,
+ bool needreport, bool *firstreport)
+{
+ int cpu;
+
+ if (!ACCESS_ONCE(t->rcu_tasks_holdout) ||
+ t->rcu_tasks_nvcsw != ACCESS_ONCE(t->nvcsw) ||
+ !ACCESS_ONCE(t->on_rq) ||
+ (IS_ENABLED(CONFIG_NO_HZ_FULL) &&
+ !is_idle_task(t) && t->rcu_tasks_idle_cpu >= 0)) {
+ ACCESS_ONCE(t->rcu_tasks_holdout) = false;
+ list_del_init(&t->rcu_tasks_holdout_list);
+ put_task_struct(t);
+ return;
+ }
+ if (!needreport)
+ return;
+ if (*firstreport) {
+ pr_err("INFO: rcu_tasks detected stalls on tasks:\n");
+ *firstreport = false;
+ }
+ cpu = task_cpu(t);
+ pr_alert("%p: %c%c nvcsw: %lu/%lu holdout: %d idle_cpu: %d/%d\n",
+ t, ".I"[is_idle_task(t)],
+ "N."[cpu < 0 || !tick_nohz_full_cpu(cpu)],
+ t->rcu_tasks_nvcsw, t->nvcsw, t->rcu_tasks_holdout,
+ t->rcu_tasks_idle_cpu, cpu);
+ sched_show_task(t);
+}
+
+/* RCU-tasks kthread that detects grace periods and invokes callbacks. */
+static int __noreturn rcu_tasks_kthread(void *arg)
+{
+ unsigned long flags;
+ struct task_struct *g, *t;
+ unsigned long lastreport;
+ struct rcu_head *list;
+ struct rcu_head *next;
+ LIST_HEAD(rcu_tasks_holdouts);
+
+ /* FIXME: Add housekeeping affinity. */
+
+ /*
+ * Each pass through the following loop makes one check for
+ * newly arrived callbacks, and, if there are some, waits for
+ * one RCU-tasks grace period and then invokes the callbacks.
+ * This loop is terminated by the system going down. ;-)
+ */
+ for (;;) {
+
+ /* Pick up any new callbacks. */
+ raw_spin_lock_irqsave(&rcu_tasks_cbs_lock, flags);
+ list = rcu_tasks_cbs_head;
+ rcu_tasks_cbs_head = NULL;
+ rcu_tasks_cbs_tail = &rcu_tasks_cbs_head;
+ raw_spin_unlock_irqrestore(&rcu_tasks_cbs_lock, flags);
+
+ /* If there were none, wait a bit and start over. */
+ if (!list) {
+ wait_event_interruptible(rcu_tasks_cbs_wq,
+ rcu_tasks_cbs_head);
+ if (!rcu_tasks_cbs_head) {
+ WARN_ON(signal_pending(current));
+ schedule_timeout_interruptible(HZ/10);
+ }
+ continue;
+ }
+
+ /*
+ * Wait for all pre-existing t->on_rq and t->nvcsw
+ * transitions to complete. Invoking synchronize_sched()
+ * suffices because all these transitions occur with
+ * interrupts disabled. Without this synchronize_sched(),
+ * a read-side critical section that started before the
+ * grace period might be incorrectly seen as having started
+ * after the grace period.
+ *
+ * This synchronize_sched() also dispenses with the
+ * need for a memory barrier on the first store to
+ * ->rcu_tasks_holdout, as it forces the store to happen
+ * after the beginning of the grace period.
+ */
+ synchronize_sched();
+
+ /*
+ * There were callbacks, so we need to wait for an
+ * RCU-tasks grace period. Start off by scanning
+ * the task list for tasks that are not already
+ * voluntarily blocked. Mark these tasks and make
+ * a list of them in rcu_tasks_holdouts.
+ */
+ rcu_read_lock();
+ for_each_process_thread(g, t) {
+ if (t != current && ACCESS_ONCE(t->on_rq) &&
+ !is_idle_task(t)) {
+ get_task_struct(t);
+ t->rcu_tasks_nvcsw = ACCESS_ONCE(t->nvcsw);
+ ACCESS_ONCE(t->rcu_tasks_holdout) = true;
+ list_add(&t->rcu_tasks_holdout_list,
+ &rcu_tasks_holdouts);
+ }
+ }
+ rcu_read_unlock();
+
+ /*
+ * Wait for tasks that are in the process of exiting.
+ * This does only part of the job, ensuring that all
+ * tasks that were previously exiting reach the point
+ * where they have disabled preemption, allowing the
+ * later synchronize_sched() to finish the job.
+ */
+ synchronize_srcu(&tasks_rcu_exit_srcu);
+
+ /*
+ * Each pass through the following loop scans the list
+ * of holdout tasks, removing any that are no longer
+ * holdouts. When the list is empty, we are done.
+ */
+ lastreport = jiffies;
+ while (!list_empty(&rcu_tasks_holdouts)) {
+ bool firstreport;
+ bool needreport;
+ int rtst;
+ struct task_struct *t1;
+
+ schedule_timeout_interruptible(HZ);
+ rtst = ACCESS_ONCE(rcu_task_stall_timeout);
+ needreport = rtst > 0 &&
+ time_after(jiffies, lastreport + rtst);
+ if (needreport)
+ lastreport = jiffies;
+ firstreport = true;
+ WARN_ON(signal_pending(current));
+ list_for_each_entry_safe(t, t1, &rcu_tasks_holdouts,
+ rcu_tasks_holdout_list) {
+ check_holdout_task(t, needreport, &firstreport);
+ cond_resched();
+ }
+ }
+
+ /*
+ * Because ->on_rq and ->nvcsw are not guaranteed
+ * to have a full memory barriers prior to them in the
+ * schedule() path, memory reordering on other CPUs could
+ * cause their RCU-tasks read-side critical sections to
+ * extend past the end of the grace period. However,
+ * because these ->nvcsw updates are carried out with
+ * interrupts disabled, we can use synchronize_sched()
+ * to force the needed ordering on all such CPUs.
+ *
+ * This synchronize_sched() also confines all
+ * ->rcu_tasks_holdout accesses to be within the grace
+ * period, avoiding the need for memory barriers for
+ * ->rcu_tasks_holdout accesses.
+ *
+ * In addition, this synchronize_sched() waits for exiting
+ * tasks to complete their final preempt_disable() region
+ * of execution, cleaning up after the synchronize_srcu()
+ * above.
+ */
+ synchronize_sched();
+
+ /* Invoke the callbacks. */
+ while (list) {
+ next = list->next;
+ local_bh_disable();
+ list->func(list);
+ local_bh_enable();
+ list = next;
+ cond_resched();
+ }
+ schedule_timeout_uninterruptible(HZ/10);
+ }
+}
+
+/* Spawn rcu_tasks_kthread() at first call to call_rcu_tasks(). */
+static void rcu_spawn_tasks_kthread(void)
+{
+ static DEFINE_MUTEX(rcu_tasks_kthread_mutex);
+ static struct task_struct *rcu_tasks_kthread_ptr;
+ struct task_struct *t;
+
+ if (ACCESS_ONCE(rcu_tasks_kthread_ptr)) {
+ smp_mb(); /* Ensure caller sees full kthread. */
+ return;
+ }
+ mutex_lock(&rcu_tasks_kthread_mutex);
+ if (rcu_tasks_kthread_ptr) {
+ mutex_unlock(&rcu_tasks_kthread_mutex);
+ return;
+ }
+ t = kthread_run(rcu_tasks_kthread, NULL, "rcu_tasks_kthread");
+ BUG_ON(IS_ERR(t));
+ smp_mb(); /* Ensure others see full kthread. */
+ ACCESS_ONCE(rcu_tasks_kthread_ptr) = t;
+ mutex_unlock(&rcu_tasks_kthread_mutex);
+}
+
+#endif /* #ifdef CONFIG_TASKS_RCU */
diff --git a/kernel/reboot.c b/kernel/reboot.c
index a3a9e240fcdb..5925f5ae8dff 100644
--- a/kernel/reboot.c
+++ b/kernel/reboot.c
@@ -104,6 +104,87 @@ int unregister_reboot_notifier(struct notifier_block *nb)
}
EXPORT_SYMBOL(unregister_reboot_notifier);
+/*
+ * Notifier list for kernel code which wants to be called
+ * to restart the system.
+ */
+static ATOMIC_NOTIFIER_HEAD(restart_handler_list);
+
+/**
+ * register_restart_handler - Register function to be called to reset
+ * the system
+ * @nb: Info about handler function to be called
+ * @nb->priority: Handler priority. Handlers should follow the
+ * following guidelines for setting priorities.
+ * 0: Restart handler of last resort,
+ * with limited restart capabilities
+ * 128: Default restart handler; use if no other
+ * restart handler is expected to be available,
+ * and/or if restart functionality is
+ * sufficient to restart the entire system
+ * 255: Highest priority restart handler, will
+ * preempt all other restart handlers
+ *
+ * Registers a function with code to be called to restart the
+ * system.
+ *
+ * Registered functions will be called from machine_restart as last
+ * step of the restart sequence (if the architecture specific
+ * machine_restart function calls do_kernel_restart - see below
+ * for details).
+ * Registered functions are expected to restart the system immediately.
+ * If more than one function is registered, the restart handler priority
+ * selects which function will be called first.
+ *
+ * Restart handlers are expected to be registered from non-architecture
+ * code, typically from drivers. A typical use case would be a system
+ * where restart functionality is provided through a watchdog. Multiple
+ * restart handlers may exist; for example, one restart handler might
+ * restart the entire system, while another only restarts the CPU.
+ * In such cases, the restart handler which only restarts part of the
+ * hardware is expected to register with low priority to ensure that
+ * it only runs if no other means to restart the system is available.
+ *
+ * Currently always returns zero, as atomic_notifier_chain_register()
+ * always returns zero.
+ */
+int register_restart_handler(struct notifier_block *nb)
+{
+ return atomic_notifier_chain_register(&restart_handler_list, nb);
+}
+EXPORT_SYMBOL(register_restart_handler);
+
+/**
+ * unregister_restart_handler - Unregister previously registered
+ * restart handler
+ * @nb: Hook to be unregistered
+ *
+ * Unregisters a previously registered restart handler function.
+ *
+ * Returns zero on success, or %-ENOENT on failure.
+ */
+int unregister_restart_handler(struct notifier_block *nb)
+{
+ return atomic_notifier_chain_unregister(&restart_handler_list, nb);
+}
+EXPORT_SYMBOL(unregister_restart_handler);
+
+/**
+ * do_kernel_restart - Execute kernel restart handler call chain
+ *
+ * Calls functions registered with register_restart_handler.
+ *
+ * Expected to be called from machine_restart as last step of the restart
+ * sequence.
+ *
+ * Restarts the system immediately if a restart handler function has been
+ * registered. Otherwise does nothing.
+ */
+void do_kernel_restart(char *cmd)
+{
+ atomic_notifier_call_chain(&restart_handler_list, reboot_mode, cmd);
+}
+
void migrate_to_reboot_cpu(void)
{
/* The boot cpu is always logical cpu 0 */
diff --git a/kernel/resource.c b/kernel/resource.c
index da14b8d09296..0bcebffc4e77 100644
--- a/kernel/resource.c
+++ b/kernel/resource.c
@@ -351,15 +351,12 @@ static int find_next_iomem_res(struct resource *res, char *name,
end = res->end;
BUG_ON(start >= end);
- read_lock(&resource_lock);
-
- if (first_level_children_only) {
- p = iomem_resource.child;
+ if (first_level_children_only)
sibling_only = true;
- } else
- p = &iomem_resource;
- while ((p = next_resource(p, sibling_only))) {
+ read_lock(&resource_lock);
+
+ for (p = iomem_resource.child; p; p = next_resource(p, sibling_only)) {
if (p->flags != res->flags)
continue;
if (name && strcmp(p->name, name))
@@ -494,6 +491,42 @@ int __weak page_is_ram(unsigned long pfn)
}
EXPORT_SYMBOL_GPL(page_is_ram);
+/*
+ * Search for a resouce entry that fully contains the specified region.
+ * If found, return 1 if it is RAM, 0 if not.
+ * If not found, or region is not fully contained, return -1
+ *
+ * Used by the ioremap functions to ensure the user is not remapping RAM and is
+ * a vast speed up over walking through the resource table page by page.
+ */
+int region_is_ram(resource_size_t start, unsigned long size)
+{
+ struct resource *p;
+ resource_size_t end = start + size - 1;
+ int flags = IORESOURCE_MEM | IORESOURCE_BUSY;
+ const char *name = "System RAM";
+ int ret = -1;
+
+ read_lock(&resource_lock);
+ for (p = iomem_resource.child; p ; p = p->sibling) {
+ if (end < p->start)
+ continue;
+
+ if (p->start <= start && end <= p->end) {
+ /* resource fully contains region */
+ if ((p->flags != flags) || strcmp(p->name, name))
+ ret = 0;
+ else
+ ret = 1;
+ break;
+ }
+ if (p->end < start)
+ break; /* not found */
+ }
+ read_unlock(&resource_lock);
+ return ret;
+}
+
void __weak arch_remove_reservations(struct resource *avail)
{
}
@@ -1248,6 +1281,76 @@ int release_mem_region_adjustable(struct resource *parent,
/*
* Managed region resource
*/
+static void devm_resource_release(struct device *dev, void *ptr)
+{
+ struct resource **r = ptr;
+
+ release_resource(*r);
+}
+
+/**
+ * devm_request_resource() - request and reserve an I/O or memory resource
+ * @dev: device for which to request the resource
+ * @root: root of the resource tree from which to request the resource
+ * @new: descriptor of the resource to request
+ *
+ * This is a device-managed version of request_resource(). There is usually
+ * no need to release resources requested by this function explicitly since
+ * that will be taken care of when the device is unbound from its driver.
+ * If for some reason the resource needs to be released explicitly, because
+ * of ordering issues for example, drivers must call devm_release_resource()
+ * rather than the regular release_resource().
+ *
+ * When a conflict is detected between any existing resources and the newly
+ * requested resource, an error message will be printed.
+ *
+ * Returns 0 on success or a negative error code on failure.
+ */
+int devm_request_resource(struct device *dev, struct resource *root,
+ struct resource *new)
+{
+ struct resource *conflict, **ptr;
+
+ ptr = devres_alloc(devm_resource_release, sizeof(*ptr), GFP_KERNEL);
+ if (!ptr)
+ return -ENOMEM;
+
+ *ptr = new;
+
+ conflict = request_resource_conflict(root, new);
+ if (conflict) {
+ dev_err(dev, "resource collision: %pR conflicts with %s %pR\n",
+ new, conflict->name, conflict);
+ devres_free(ptr);
+ return -EBUSY;
+ }
+
+ devres_add(dev, ptr);
+ return 0;
+}
+EXPORT_SYMBOL(devm_request_resource);
+
+static int devm_resource_match(struct device *dev, void *res, void *data)
+{
+ struct resource **ptr = res;
+
+ return *ptr == data;
+}
+
+/**
+ * devm_release_resource() - release a previously requested resource
+ * @dev: device for which to release the resource
+ * @new: descriptor of the resource to release
+ *
+ * Releases a resource previously requested using devm_request_resource().
+ */
+void devm_release_resource(struct device *dev, struct resource *new)
+{
+ WARN_ON(devres_release(dev, devm_resource_release, devm_resource_match,
+ new));
+}
+EXPORT_SYMBOL(devm_release_resource);
+
struct region_devres {
struct resource *parent;
resource_size_t start;
diff --git a/kernel/sched/auto_group.c b/kernel/sched/auto_group.c
index e73efba98301..8a2e230fb86a 100644
--- a/kernel/sched/auto_group.c
+++ b/kernel/sched/auto_group.c
@@ -148,11 +148,8 @@ autogroup_move_group(struct task_struct *p, struct autogroup *ag)
if (!ACCESS_ONCE(sysctl_sched_autogroup_enabled))
goto out;
- t = p;
- do {
+ for_each_thread(p, t)
sched_move_task(t);
- } while_each_thread(p, t);
-
out:
unlock_task_sighand(p, &flags);
autogroup_kref_put(prev);
diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index ec1a286684a5..44999505e1bf 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -90,22 +90,6 @@
#define CREATE_TRACE_POINTS
#include <trace/events/sched.h>
-#ifdef smp_mb__before_atomic
-void __smp_mb__before_atomic(void)
-{
- smp_mb__before_atomic();
-}
-EXPORT_SYMBOL(__smp_mb__before_atomic);
-#endif
-
-#ifdef smp_mb__after_atomic
-void __smp_mb__after_atomic(void)
-{
- smp_mb__after_atomic();
-}
-EXPORT_SYMBOL(__smp_mb__after_atomic);
-#endif
-
void start_bandwidth_timer(struct hrtimer *period_timer, ktime_t period)
{
unsigned long delta;
@@ -333,9 +317,12 @@ static inline struct rq *__task_rq_lock(struct task_struct *p)
for (;;) {
rq = task_rq(p);
raw_spin_lock(&rq->lock);
- if (likely(rq == task_rq(p)))
+ if (likely(rq == task_rq(p) && !task_on_rq_migrating(p)))
return rq;
raw_spin_unlock(&rq->lock);
+
+ while (unlikely(task_on_rq_migrating(p)))
+ cpu_relax();
}
}
@@ -352,10 +339,13 @@ static struct rq *task_rq_lock(struct task_struct *p, unsigned long *flags)
raw_spin_lock_irqsave(&p->pi_lock, *flags);
rq = task_rq(p);
raw_spin_lock(&rq->lock);
- if (likely(rq == task_rq(p)))
+ if (likely(rq == task_rq(p) && !task_on_rq_migrating(p)))
return rq;
raw_spin_unlock(&rq->lock);
raw_spin_unlock_irqrestore(&p->pi_lock, *flags);
+
+ while (unlikely(task_on_rq_migrating(p)))
+ cpu_relax();
}
}
@@ -449,7 +439,15 @@ static void __hrtick_start(void *arg)
void hrtick_start(struct rq *rq, u64 delay)
{
struct hrtimer *timer = &rq->hrtick_timer;
- ktime_t time = ktime_add_ns(timer->base->get_time(), delay);
+ ktime_t time;
+ s64 delta;
+
+ /*
+ * Don't schedule slices shorter than 10000ns, that just
+ * doesn't make sense and can cause timer DoS.
+ */
+ delta = max_t(s64, delay, 10000LL);
+ time = ktime_add_ns(timer->base->get_time(), delta);
hrtimer_set_expires(timer, time);
@@ -1043,7 +1041,7 @@ void check_preempt_curr(struct rq *rq, struct task_struct *p, int flags)
* A queue event has occurred, and we're going to schedule. In
* this case, we can save a useless back to back clock update.
*/
- if (rq->curr->on_rq && test_tsk_need_resched(rq->curr))
+ if (task_on_rq_queued(rq->curr) && test_tsk_need_resched(rq->curr))
rq->skip_clock_update = 1;
}
@@ -1088,7 +1086,7 @@ void set_task_cpu(struct task_struct *p, unsigned int new_cpu)
static void __migrate_swap_task(struct task_struct *p, int cpu)
{
- if (p->on_rq) {
+ if (task_on_rq_queued(p)) {
struct rq *src_rq, *dst_rq;
src_rq = task_rq(p);
@@ -1214,7 +1212,7 @@ static int migration_cpu_stop(void *data);
unsigned long wait_task_inactive(struct task_struct *p, long match_state)
{
unsigned long flags;
- int running, on_rq;
+ int running, queued;
unsigned long ncsw;
struct rq *rq;
@@ -1252,7 +1250,7 @@ unsigned long wait_task_inactive(struct task_struct *p, long match_state)
rq = task_rq_lock(p, &flags);
trace_sched_wait_task(p);
running = task_running(rq, p);
- on_rq = p->on_rq;
+ queued = task_on_rq_queued(p);
ncsw = 0;
if (!match_state || p->state == match_state)
ncsw = p->nvcsw | LONG_MIN; /* sets MSB */
@@ -1284,7 +1282,7 @@ unsigned long wait_task_inactive(struct task_struct *p, long match_state)
* running right now), it's preempted, and we should
* yield - it could be a while.
*/
- if (unlikely(on_rq)) {
+ if (unlikely(queued)) {
ktime_t to = ktime_set(0, NSEC_PER_SEC/HZ);
set_current_state(TASK_UNINTERRUPTIBLE);
@@ -1478,7 +1476,7 @@ ttwu_stat(struct task_struct *p, int cpu, int wake_flags)
static void ttwu_activate(struct rq *rq, struct task_struct *p, int en_flags)
{
activate_task(rq, p, en_flags);
- p->on_rq = 1;
+ p->on_rq = TASK_ON_RQ_QUEUED;
/* if a worker is waking up, notify workqueue */
if (p->flags & PF_WQ_WORKER)
@@ -1537,7 +1535,7 @@ static int ttwu_remote(struct task_struct *p, int wake_flags)
int ret = 0;
rq = __task_rq_lock(p);
- if (p->on_rq) {
+ if (task_on_rq_queued(p)) {
/* check_preempt_curr() may use rq clock */
update_rq_clock(rq);
ttwu_do_wakeup(rq, p, wake_flags);
@@ -1620,6 +1618,25 @@ static void ttwu_queue_remote(struct task_struct *p, int cpu)
}
}
+void wake_up_if_idle(int cpu)
+{
+ struct rq *rq = cpu_rq(cpu);
+ unsigned long flags;
+
+ if (!is_idle_task(rq->curr))
+ return;
+
+ if (set_nr_if_polling(rq->idle)) {
+ trace_sched_wake_idle_without_ipi(cpu);
+ } else {
+ raw_spin_lock_irqsave(&rq->lock, flags);
+ if (is_idle_task(rq->curr))
+ smp_send_reschedule(cpu);
+ /* Else cpu is not in idle, do nothing here */
+ raw_spin_unlock_irqrestore(&rq->lock, flags);
+ }
+}
+
bool cpus_share_cache(int this_cpu, int that_cpu)
{
return per_cpu(sd_llc_id, this_cpu) == per_cpu(sd_llc_id, that_cpu);
@@ -1742,7 +1759,7 @@ static void try_to_wake_up_local(struct task_struct *p)
if (!(p->state & TASK_NORMAL))
goto out;
- if (!p->on_rq)
+ if (!task_on_rq_queued(p))
ttwu_activate(rq, p, ENQUEUE_WAKEUP);
ttwu_do_wakeup(rq, p, 0);
@@ -1776,6 +1793,20 @@ int wake_up_state(struct task_struct *p, unsigned int state)
}
/*
+ * This function clears the sched_dl_entity static params.
+ */
+void __dl_clear_params(struct task_struct *p)
+{
+ struct sched_dl_entity *dl_se = &p->dl;
+
+ dl_se->dl_runtime = 0;
+ dl_se->dl_deadline = 0;
+ dl_se->dl_period = 0;
+ dl_se->flags = 0;
+ dl_se->dl_bw = 0;
+}
+
+/*
* Perform scheduler related setup for a newly forked process p.
* p is forked by current.
*
@@ -1799,10 +1830,7 @@ static void __sched_fork(unsigned long clone_flags, struct task_struct *p)
RB_CLEAR_NODE(&p->dl.rb_node);
hrtimer_init(&p->dl.dl_timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
- p->dl.dl_runtime = p->dl.runtime = 0;
- p->dl.dl_deadline = p->dl.deadline = 0;
- p->dl.dl_period = 0;
- p->dl.flags = 0;
+ __dl_clear_params(p);
INIT_LIST_HEAD(&p->rt.run_list);
@@ -1977,6 +2005,8 @@ unsigned long to_ratio(u64 period, u64 runtime)
#ifdef CONFIG_SMP
inline struct dl_bw *dl_bw_of(int i)
{
+ rcu_lockdep_assert(rcu_read_lock_sched_held(),
+ "sched RCU must be held");
return &cpu_rq(i)->rd->dl_bw;
}
@@ -1985,6 +2015,8 @@ static inline int dl_bw_cpus(int i)
struct root_domain *rd = cpu_rq(i)->rd;
int cpus = 0;
+ rcu_lockdep_assert(rcu_read_lock_sched_held(),
+ "sched RCU must be held");
for_each_cpu_and(i, rd->span, cpu_active_mask)
cpus++;
@@ -2095,7 +2127,7 @@ void wake_up_new_task(struct task_struct *p)
init_task_runnable_average(p);
rq = __task_rq_lock(p);
activate_task(rq, p, 0);
- p->on_rq = 1;
+ p->on_rq = TASK_ON_RQ_QUEUED;
trace_sched_wakeup_new(p, true);
check_preempt_curr(rq, p, WF_FORK);
#ifdef CONFIG_SMP
@@ -2287,10 +2319,6 @@ asmlinkage __visible void schedule_tail(struct task_struct *prev)
*/
post_schedule(rq);
-#ifdef __ARCH_WANT_UNLOCKED_CTXSW
- /* In this case, finish_task_switch does not reenable preemption */
- preempt_enable();
-#endif
if (current->set_child_tid)
put_user(task_pid_vnr(current), current->set_child_tid);
}
@@ -2333,9 +2361,7 @@ 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:
*/
-#ifndef __ARCH_WANT_UNLOCKED_CTXSW
spin_release(&rq->lock.dep_map, 1, _THIS_IP_);
-#endif
context_tracking_task_switch(prev, next);
/* Here we just switch the register state and the stack. */
@@ -2366,6 +2392,18 @@ unsigned long nr_running(void)
return sum;
}
+/*
+ * Check if only the current task is running on the cpu.
+ */
+bool single_task_running(void)
+{
+ if (cpu_rq(smp_processor_id())->nr_running == 1)
+ return true;
+ else
+ return false;
+}
+EXPORT_SYMBOL(single_task_running);
+
unsigned long long nr_context_switches(void)
{
int i;
@@ -2451,7 +2489,7 @@ static u64 do_task_delta_exec(struct task_struct *p, struct rq *rq)
* project cycles that may never be accounted to this
* thread, breaking clock_gettime().
*/
- if (task_current(rq, p) && p->on_rq) {
+ if (task_current(rq, p) && task_on_rq_queued(p)) {
update_rq_clock(rq);
ns = rq_clock_task(rq) - p->se.exec_start;
if ((s64)ns < 0)
@@ -2497,7 +2535,7 @@ unsigned long long task_sched_runtime(struct task_struct *p)
* If we see ->on_cpu without ->on_rq, the task is leaving, and has
* been accounted, so we're correct here as well.
*/
- if (!p->on_cpu || !p->on_rq)
+ if (!p->on_cpu || !task_on_rq_queued(p))
return p->se.sum_exec_runtime;
#endif
@@ -2660,6 +2698,9 @@ static noinline void __schedule_bug(struct task_struct *prev)
*/
static inline void schedule_debug(struct task_struct *prev)
{
+#ifdef CONFIG_SCHED_STACK_END_CHECK
+ BUG_ON(unlikely(task_stack_end_corrupted(prev)));
+#endif
/*
* Test if we are atomic. Since do_exit() needs to call into
* schedule() atomically, we ignore that path. Otherwise whine
@@ -2801,7 +2842,7 @@ need_resched:
switch_count = &prev->nvcsw;
}
- if (prev->on_rq || rq->skip_clock_update < 0)
+ if (task_on_rq_queued(prev) || rq->skip_clock_update < 0)
update_rq_clock(rq);
next = pick_next_task(rq, prev);
@@ -2966,7 +3007,7 @@ EXPORT_SYMBOL(default_wake_function);
*/
void rt_mutex_setprio(struct task_struct *p, int prio)
{
- int oldprio, on_rq, running, enqueue_flag = 0;
+ int oldprio, queued, running, enqueue_flag = 0;
struct rq *rq;
const struct sched_class *prev_class;
@@ -2995,12 +3036,12 @@ void rt_mutex_setprio(struct task_struct *p, int prio)
trace_sched_pi_setprio(p, prio);
oldprio = p->prio;
prev_class = p->sched_class;
- on_rq = p->on_rq;
+ queued = task_on_rq_queued(p);
running = task_current(rq, p);
- if (on_rq)
+ if (queued)
dequeue_task(rq, p, 0);
if (running)
- p->sched_class->put_prev_task(rq, p);
+ put_prev_task(rq, p);
/*
* Boosting condition are:
@@ -3037,7 +3078,7 @@ void rt_mutex_setprio(struct task_struct *p, int prio)
if (running)
p->sched_class->set_curr_task(rq);
- if (on_rq)
+ if (queued)
enqueue_task(rq, p, enqueue_flag);
check_class_changed(rq, p, prev_class, oldprio);
@@ -3048,7 +3089,7 @@ out_unlock:
void set_user_nice(struct task_struct *p, long nice)
{
- int old_prio, delta, on_rq;
+ int old_prio, delta, queued;
unsigned long flags;
struct rq *rq;
@@ -3069,8 +3110,8 @@ void set_user_nice(struct task_struct *p, long nice)
p->static_prio = NICE_TO_PRIO(nice);
goto out_unlock;
}
- on_rq = p->on_rq;
- if (on_rq)
+ queued = task_on_rq_queued(p);
+ if (queued)
dequeue_task(rq, p, 0);
p->static_prio = NICE_TO_PRIO(nice);
@@ -3079,7 +3120,7 @@ void set_user_nice(struct task_struct *p, long nice)
p->prio = effective_prio(p);
delta = p->prio - old_prio;
- if (on_rq) {
+ if (queued) {
enqueue_task(rq, p, 0);
/*
* If the task increased its priority or is running and
@@ -3351,7 +3392,7 @@ static int __sched_setscheduler(struct task_struct *p,
{
int newprio = dl_policy(attr->sched_policy) ? MAX_DL_PRIO - 1 :
MAX_RT_PRIO - 1 - attr->sched_priority;
- int retval, oldprio, oldpolicy = -1, on_rq, running;
+ int retval, oldprio, oldpolicy = -1, queued, running;
int policy = attr->sched_policy;
unsigned long flags;
const struct sched_class *prev_class;
@@ -3548,19 +3589,19 @@ change:
return 0;
}
- on_rq = p->on_rq;
+ queued = task_on_rq_queued(p);
running = task_current(rq, p);
- if (on_rq)
+ if (queued)
dequeue_task(rq, p, 0);
if (running)
- p->sched_class->put_prev_task(rq, p);
+ put_prev_task(rq, p);
prev_class = p->sched_class;
__setscheduler(rq, p, attr);
if (running)
p->sched_class->set_curr_task(rq);
- if (on_rq) {
+ if (queued) {
/*
* We enqueue to tail when the priority of a task is
* increased (user space view).
@@ -3984,14 +4025,14 @@ long sched_setaffinity(pid_t pid, const struct cpumask *in_mask)
rcu_read_lock();
if (!ns_capable(__task_cred(p)->user_ns, CAP_SYS_NICE)) {
rcu_read_unlock();
- goto out_unlock;
+ goto out_free_new_mask;
}
rcu_read_unlock();
}
retval = security_task_setscheduler(p);
if (retval)
- goto out_unlock;
+ goto out_free_new_mask;
cpuset_cpus_allowed(p, cpus_allowed);
@@ -4004,13 +4045,14 @@ long sched_setaffinity(pid_t pid, const struct cpumask *in_mask)
* root_domain.
*/
#ifdef CONFIG_SMP
- if (task_has_dl_policy(p)) {
- const struct cpumask *span = task_rq(p)->rd->span;
-
- if (dl_bandwidth_enabled() && !cpumask_subset(span, new_mask)) {
+ if (task_has_dl_policy(p) && dl_bandwidth_enabled()) {
+ rcu_read_lock();
+ if (!cpumask_subset(task_rq(p)->rd->span, new_mask)) {
retval = -EBUSY;
- goto out_unlock;
+ rcu_read_unlock();
+ goto out_free_new_mask;
}
+ rcu_read_unlock();
}
#endif
again:
@@ -4028,7 +4070,7 @@ again:
goto again;
}
}
-out_unlock:
+out_free_new_mask:
free_cpumask_var(new_mask);
out_free_cpus_allowed:
free_cpumask_var(cpus_allowed);
@@ -4512,7 +4554,7 @@ void show_state_filter(unsigned long state_filter)
" task PC stack pid father\n");
#endif
rcu_read_lock();
- do_each_thread(g, p) {
+ for_each_process_thread(g, p) {
/*
* reset the NMI-timeout, listing all files on a slow
* console might take a lot of time:
@@ -4520,7 +4562,7 @@ void show_state_filter(unsigned long state_filter)
touch_nmi_watchdog();
if (!state_filter || (p->state & state_filter))
sched_show_task(p);
- } while_each_thread(g, p);
+ }
touch_all_softlockup_watchdogs();
@@ -4575,7 +4617,7 @@ void init_idle(struct task_struct *idle, int cpu)
rcu_read_unlock();
rq->curr = rq->idle = idle;
- idle->on_rq = 1;
+ idle->on_rq = TASK_ON_RQ_QUEUED;
#if defined(CONFIG_SMP)
idle->on_cpu = 1;
#endif
@@ -4596,6 +4638,33 @@ void init_idle(struct task_struct *idle, int cpu)
}
#ifdef CONFIG_SMP
+/*
+ * move_queued_task - move a queued task to new rq.
+ *
+ * Returns (locked) new rq. Old rq's lock is released.
+ */
+static struct rq *move_queued_task(struct task_struct *p, int new_cpu)
+{
+ struct rq *rq = task_rq(p);
+
+ lockdep_assert_held(&rq->lock);
+
+ dequeue_task(rq, p, 0);
+ p->on_rq = TASK_ON_RQ_MIGRATING;
+ set_task_cpu(p, new_cpu);
+ raw_spin_unlock(&rq->lock);
+
+ rq = cpu_rq(new_cpu);
+
+ raw_spin_lock(&rq->lock);
+ BUG_ON(task_cpu(p) != new_cpu);
+ p->on_rq = TASK_ON_RQ_QUEUED;
+ enqueue_task(rq, p, 0);
+ check_preempt_curr(rq, p, 0);
+
+ return rq;
+}
+
void do_set_cpus_allowed(struct task_struct *p, const struct cpumask *new_mask)
{
if (p->sched_class && p->sched_class->set_cpus_allowed)
@@ -4652,14 +4721,15 @@ int set_cpus_allowed_ptr(struct task_struct *p, const struct cpumask *new_mask)
goto out;
dest_cpu = cpumask_any_and(cpu_active_mask, new_mask);
- if (p->on_rq) {
+ 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);
stop_one_cpu(cpu_of(rq), migration_cpu_stop, &arg);
tlb_migrate_finish(p->mm);
return 0;
- }
+ } else if (task_on_rq_queued(p))
+ rq = move_queued_task(p, dest_cpu);
out:
task_rq_unlock(rq, p, &flags);
@@ -4680,20 +4750,20 @@ EXPORT_SYMBOL_GPL(set_cpus_allowed_ptr);
*/
static int __migrate_task(struct task_struct *p, int src_cpu, int dest_cpu)
{
- struct rq *rq_dest, *rq_src;
+ struct rq *rq;
int ret = 0;
if (unlikely(!cpu_active(dest_cpu)))
return ret;
- rq_src = cpu_rq(src_cpu);
- rq_dest = cpu_rq(dest_cpu);
+ rq = cpu_rq(src_cpu);
raw_spin_lock(&p->pi_lock);
- double_rq_lock(rq_src, rq_dest);
+ raw_spin_lock(&rq->lock);
/* Already moved. */
if (task_cpu(p) != src_cpu)
goto done;
+
/* Affinity changed (again). */
if (!cpumask_test_cpu(dest_cpu, tsk_cpus_allowed(p)))
goto fail;
@@ -4702,16 +4772,12 @@ static int __migrate_task(struct task_struct *p, int src_cpu, int dest_cpu)
* If we're not on a rq, the next wake-up will ensure we're
* placed properly.
*/
- if (p->on_rq) {
- dequeue_task(rq_src, p, 0);
- set_task_cpu(p, dest_cpu);
- enqueue_task(rq_dest, p, 0);
- check_preempt_curr(rq_dest, p, 0);
- }
+ if (task_on_rq_queued(p))
+ rq = move_queued_task(p, dest_cpu);
done:
ret = 1;
fail:
- double_rq_unlock(rq_src, rq_dest);
+ raw_spin_unlock(&rq->lock);
raw_spin_unlock(&p->pi_lock);
return ret;
}
@@ -4743,22 +4809,22 @@ void sched_setnuma(struct task_struct *p, int nid)
{
struct rq *rq;
unsigned long flags;
- bool on_rq, running;
+ bool queued, running;
rq = task_rq_lock(p, &flags);
- on_rq = p->on_rq;
+ queued = task_on_rq_queued(p);
running = task_current(rq, p);
- if (on_rq)
+ if (queued)
dequeue_task(rq, p, 0);
if (running)
- p->sched_class->put_prev_task(rq, p);
+ put_prev_task(rq, p);
p->numa_preferred_nid = nid;
if (running)
p->sched_class->set_curr_task(rq);
- if (on_rq)
+ if (queued)
enqueue_task(rq, p, 0);
task_rq_unlock(rq, p, &flags);
}
@@ -4778,6 +4844,12 @@ static int migration_cpu_stop(void *data)
* be on another cpu but it doesn't matter.
*/
local_irq_disable();
+ /*
+ * We need to explicitly wake pending tasks before running
+ * __migrate_task() such that we will not miss enforcing cpus_allowed
+ * during wakeups, see set_cpus_allowed_ptr()'s TASK_WAKING test.
+ */
+ sched_ttwu_pending();
__migrate_task(arg->task, raw_smp_processor_id(), arg->dest_cpu);
local_irq_enable();
return 0;
@@ -5188,6 +5260,7 @@ static int sched_cpu_inactive(struct notifier_block *nfb,
{
unsigned long flags;
long cpu = (long)hcpu;
+ struct dl_bw *dl_b;
switch (action & ~CPU_TASKS_FROZEN) {
case CPU_DOWN_PREPARE:
@@ -5195,15 +5268,19 @@ static int sched_cpu_inactive(struct notifier_block *nfb,
/* explicitly allow suspend */
if (!(action & CPU_TASKS_FROZEN)) {
- struct dl_bw *dl_b = dl_bw_of(cpu);
bool overflow;
int cpus;
+ rcu_read_lock_sched();
+ dl_b = dl_bw_of(cpu);
+
raw_spin_lock_irqsave(&dl_b->lock, flags);
cpus = dl_bw_cpus(cpu);
overflow = __dl_overflow(dl_b, cpus, 0, 0);
raw_spin_unlock_irqrestore(&dl_b->lock, flags);
+ rcu_read_unlock_sched();
+
if (overflow)
return notifier_from_errno(-EBUSY);
}
@@ -5746,7 +5823,7 @@ build_overlap_sched_groups(struct sched_domain *sd, int cpu)
const struct cpumask *span = sched_domain_span(sd);
struct cpumask *covered = sched_domains_tmpmask;
struct sd_data *sdd = sd->private;
- struct sched_domain *child;
+ struct sched_domain *sibling;
int i;
cpumask_clear(covered);
@@ -5757,10 +5834,10 @@ build_overlap_sched_groups(struct sched_domain *sd, int cpu)
if (cpumask_test_cpu(i, covered))
continue;
- child = *per_cpu_ptr(sdd->sd, i);
+ sibling = *per_cpu_ptr(sdd->sd, i);
/* See the comment near build_group_mask(). */
- if (!cpumask_test_cpu(i, sched_domain_span(child)))
+ if (!cpumask_test_cpu(i, sched_domain_span(sibling)))
continue;
sg = kzalloc_node(sizeof(struct sched_group) + cpumask_size(),
@@ -5770,10 +5847,9 @@ build_overlap_sched_groups(struct sched_domain *sd, int cpu)
goto fail;
sg_span = sched_group_cpus(sg);
- if (child->child) {
- child = child->child;
- cpumask_copy(sg_span, sched_domain_span(child));
- } else
+ if (sibling->child)
+ cpumask_copy(sg_span, sched_domain_span(sibling->child));
+ else
cpumask_set_cpu(i, sg_span);
cpumask_or(covered, covered, sg_span);
@@ -7124,13 +7200,13 @@ static void normalize_task(struct rq *rq, struct task_struct *p)
.sched_policy = SCHED_NORMAL,
};
int old_prio = p->prio;
- int on_rq;
+ int queued;
- on_rq = p->on_rq;
- if (on_rq)
+ queued = task_on_rq_queued(p);
+ if (queued)
dequeue_task(rq, p, 0);
__setscheduler(rq, p, &attr);
- if (on_rq) {
+ if (queued) {
enqueue_task(rq, p, 0);
resched_curr(rq);
}
@@ -7144,12 +7220,12 @@ void normalize_rt_tasks(void)
unsigned long flags;
struct rq *rq;
- read_lock_irqsave(&tasklist_lock, flags);
- do_each_thread(g, p) {
+ read_lock(&tasklist_lock);
+ for_each_process_thread(g, p) {
/*
* Only normalize user tasks:
*/
- if (!p->mm)
+ if (p->flags & PF_KTHREAD)
continue;
p->se.exec_start = 0;
@@ -7164,21 +7240,16 @@ void normalize_rt_tasks(void)
* Renice negative nice level userspace
* tasks back to 0:
*/
- if (task_nice(p) < 0 && p->mm)
+ if (task_nice(p) < 0)
set_user_nice(p, 0);
continue;
}
- raw_spin_lock(&p->pi_lock);
- rq = __task_rq_lock(p);
-
+ rq = task_rq_lock(p, &flags);
normalize_task(rq, p);
-
- __task_rq_unlock(rq);
- raw_spin_unlock(&p->pi_lock);
- } while_each_thread(g, p);
-
- read_unlock_irqrestore(&tasklist_lock, flags);
+ task_rq_unlock(rq, p, &flags);
+ }
+ read_unlock(&tasklist_lock);
}
#endif /* CONFIG_MAGIC_SYSRQ */
@@ -7318,19 +7389,19 @@ void sched_offline_group(struct task_group *tg)
void sched_move_task(struct task_struct *tsk)
{
struct task_group *tg;
- int on_rq, running;
+ int queued, running;
unsigned long flags;
struct rq *rq;
rq = task_rq_lock(tsk, &flags);
running = task_current(rq, tsk);
- on_rq = tsk->on_rq;
+ queued = task_on_rq_queued(tsk);
- if (on_rq)
+ if (queued)
dequeue_task(rq, tsk, 0);
if (unlikely(running))
- tsk->sched_class->put_prev_task(rq, tsk);
+ put_prev_task(rq, tsk);
tg = container_of(task_css_check(tsk, cpu_cgrp_id,
lockdep_is_held(&tsk->sighand->siglock)),
@@ -7340,14 +7411,14 @@ void sched_move_task(struct task_struct *tsk)
#ifdef CONFIG_FAIR_GROUP_SCHED
if (tsk->sched_class->task_move_group)
- tsk->sched_class->task_move_group(tsk, on_rq);
+ tsk->sched_class->task_move_group(tsk, queued);
else
#endif
set_task_rq(tsk, task_cpu(tsk));
if (unlikely(running))
tsk->sched_class->set_curr_task(rq);
- if (on_rq)
+ if (queued)
enqueue_task(rq, tsk, 0);
task_rq_unlock(rq, tsk, &flags);
@@ -7365,10 +7436,10 @@ static inline int tg_has_rt_tasks(struct task_group *tg)
{
struct task_struct *g, *p;
- do_each_thread(g, p) {
- if (rt_task(p) && task_rq(p)->rt.tg == tg)
+ for_each_process_thread(g, p) {
+ if (rt_task(p) && task_group(p) == tg)
return 1;
- } while_each_thread(g, p);
+ }
return 0;
}
@@ -7577,6 +7648,7 @@ static int sched_dl_global_constraints(void)
u64 runtime = global_rt_runtime();
u64 period = global_rt_period();
u64 new_bw = to_ratio(period, runtime);
+ struct dl_bw *dl_b;
int cpu, ret = 0;
unsigned long flags;
@@ -7590,13 +7662,16 @@ static int sched_dl_global_constraints(void)
* solutions is welcome!
*/
for_each_possible_cpu(cpu) {
- struct dl_bw *dl_b = dl_bw_of(cpu);
+ rcu_read_lock_sched();
+ dl_b = dl_bw_of(cpu);
raw_spin_lock_irqsave(&dl_b->lock, flags);
if (new_bw < dl_b->total_bw)
ret = -EBUSY;
raw_spin_unlock_irqrestore(&dl_b->lock, flags);
+ rcu_read_unlock_sched();
+
if (ret)
break;
}
@@ -7607,6 +7682,7 @@ static int sched_dl_global_constraints(void)
static void sched_dl_do_global(void)
{
u64 new_bw = -1;
+ struct dl_bw *dl_b;
int cpu;
unsigned long flags;
@@ -7620,11 +7696,14 @@ static void sched_dl_do_global(void)
* FIXME: As above...
*/
for_each_possible_cpu(cpu) {
- struct dl_bw *dl_b = dl_bw_of(cpu);
+ rcu_read_lock_sched();
+ dl_b = dl_bw_of(cpu);
raw_spin_lock_irqsave(&dl_b->lock, flags);
dl_b->bw = new_bw;
raw_spin_unlock_irqrestore(&dl_b->lock, flags);
+
+ rcu_read_unlock_sched();
}
}
@@ -8005,7 +8084,7 @@ static int tg_cfs_schedulable_down(struct task_group *tg, void *data)
struct cfs_bandwidth *parent_b = &tg->parent->cfs_bandwidth;
quota = normalize_cfs_quota(tg, d);
- parent_quota = parent_b->hierarchal_quota;
+ parent_quota = parent_b->hierarchical_quota;
/*
* ensure max(child_quota) <= parent_quota, inherit when no
@@ -8016,7 +8095,7 @@ static int tg_cfs_schedulable_down(struct task_group *tg, void *data)
else if (parent_quota != RUNTIME_INF && quota > parent_quota)
return -EINVAL;
}
- cfs_b->hierarchal_quota = quota;
+ cfs_b->hierarchical_quota = quota;
return 0;
}
diff --git a/kernel/sched/cpudeadline.c b/kernel/sched/cpudeadline.c
index bd95963dae80..539ca3ce071b 100644
--- a/kernel/sched/cpudeadline.c
+++ b/kernel/sched/cpudeadline.c
@@ -107,9 +107,7 @@ int cpudl_find(struct cpudl *cp, struct task_struct *p,
int best_cpu = -1;
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,
- later_mask, cpu_active_mask)) {
+ if (later_mask && cpumask_and(later_mask, later_mask, cp->free_cpus)) {
best_cpu = cpumask_any(later_mask);
goto out;
} else if (cpumask_test_cpu(cpudl_maximum(cp), &p->cpus_allowed) &&
diff --git a/kernel/sched/cputime.c b/kernel/sched/cputime.c
index 72fdf06ef865..8394b1ee600c 100644
--- a/kernel/sched/cputime.c
+++ b/kernel/sched/cputime.c
@@ -288,24 +288,29 @@ void thread_group_cputime(struct task_struct *tsk, struct task_cputime *times)
struct signal_struct *sig = tsk->signal;
cputime_t utime, stime;
struct task_struct *t;
-
- times->utime = sig->utime;
- times->stime = sig->stime;
- times->sum_exec_runtime = sig->sum_sched_runtime;
+ unsigned int seq, nextseq;
+ unsigned long flags;
rcu_read_lock();
- /* make sure we can trust tsk->thread_group list */
- if (!likely(pid_alive(tsk)))
- goto out;
-
- t = tsk;
+ /* Attempt a lockless read on the first round. */
+ nextseq = 0;
do {
- task_cputime(t, &utime, &stime);
- times->utime += utime;
- times->stime += stime;
- times->sum_exec_runtime += task_sched_runtime(t);
- } while_each_thread(tsk, t);
-out:
+ seq = nextseq;
+ flags = read_seqbegin_or_lock_irqsave(&sig->stats_lock, &seq);
+ times->utime = sig->utime;
+ times->stime = sig->stime;
+ times->sum_exec_runtime = sig->sum_sched_runtime;
+
+ for_each_thread(tsk, t) {
+ task_cputime(t, &utime, &stime);
+ times->utime += utime;
+ times->stime += stime;
+ times->sum_exec_runtime += task_sched_runtime(t);
+ }
+ /* If lockless access failed, take the lock. */
+ nextseq = 1;
+ } while (need_seqretry(&sig->stats_lock, seq));
+ done_seqretry_irqrestore(&sig->stats_lock, seq, flags);
rcu_read_unlock();
}
@@ -550,6 +555,23 @@ drop_precision:
}
/*
+ * Atomically advance counter to the new value. Interrupts, vcpu
+ * scheduling, and scaling inaccuracies can cause cputime_advance
+ * to be occasionally called with a new value smaller than counter.
+ * Let's enforce atomicity.
+ *
+ * Normally a caller will only go through this loop once, or not
+ * at all in case a previous caller updated counter the same jiffy.
+ */
+static void cputime_advance(cputime_t *counter, cputime_t new)
+{
+ cputime_t old;
+
+ while (new > (old = ACCESS_ONCE(*counter)))
+ cmpxchg_cputime(counter, old, new);
+}
+
+/*
* Adjust tick based cputime random precision against scheduler
* runtime accounting.
*/
@@ -594,13 +616,8 @@ static void cputime_adjust(struct task_cputime *curr,
utime = rtime - stime;
}
- /*
- * If the tick based count grows faster than the scheduler one,
- * the result of the scaling may go backward.
- * Let's enforce monotonicity.
- */
- prev->stime = max(prev->stime, stime);
- prev->utime = max(prev->utime, utime);
+ cputime_advance(&prev->stime, stime);
+ cputime_advance(&prev->utime, utime);
out:
*ut = prev->utime;
@@ -617,9 +634,6 @@ void task_cputime_adjusted(struct task_struct *p, cputime_t *ut, cputime_t *st)
cputime_adjust(&cputime, &p->prev_cputime, ut, st);
}
-/*
- * Must be called with siglock held.
- */
void thread_group_cputime_adjusted(struct task_struct *p, cputime_t *ut, cputime_t *st)
{
struct task_cputime cputime;
diff --git a/kernel/sched/deadline.c b/kernel/sched/deadline.c
index 4a608cfaecbd..256e577faf1b 100644
--- a/kernel/sched/deadline.c
+++ b/kernel/sched/deadline.c
@@ -530,7 +530,7 @@ again:
update_rq_clock(rq);
dl_se->dl_throttled = 0;
dl_se->dl_yielded = 0;
- if (p->on_rq) {
+ if (task_on_rq_queued(p)) {
enqueue_task_dl(rq, p, ENQUEUE_REPLENISH);
if (task_has_dl_policy(rq->curr))
check_preempt_curr_dl(rq, p, 0);
@@ -997,10 +997,7 @@ static void check_preempt_curr_dl(struct rq *rq, struct task_struct *p,
#ifdef CONFIG_SCHED_HRTICK
static void start_hrtick_dl(struct rq *rq, struct task_struct *p)
{
- s64 delta = p->dl.dl_runtime - p->dl.runtime;
-
- if (delta > 10000)
- hrtick_start(rq, p->dl.runtime);
+ hrtick_start(rq, p->dl.runtime);
}
#endif
@@ -1030,7 +1027,7 @@ struct task_struct *pick_next_task_dl(struct rq *rq, struct task_struct *prev)
* means a stop task can slip in, in which case we need to
* re-start task selection.
*/
- if (rq->stop && rq->stop->on_rq)
+ if (rq->stop && task_on_rq_queued(rq->stop))
return RETRY_TASK;
}
@@ -1124,10 +1121,8 @@ static void set_curr_task_dl(struct rq *rq)
static int pick_dl_task(struct rq *rq, struct task_struct *p, int cpu)
{
if (!task_running(rq, p) &&
- (cpu < 0 || cpumask_test_cpu(cpu, &p->cpus_allowed)) &&
- (p->nr_cpus_allowed > 1))
+ cpumask_test_cpu(cpu, tsk_cpus_allowed(p)))
return 1;
-
return 0;
}
@@ -1169,6 +1164,13 @@ static int find_later_rq(struct task_struct *task)
if (task->nr_cpus_allowed == 1)
return -1;
+ /*
+ * We have to consider system topology and task affinity
+ * first, then we can look for a suitable cpu.
+ */
+ cpumask_copy(later_mask, task_rq(task)->rd->span);
+ cpumask_and(later_mask, later_mask, cpu_active_mask);
+ cpumask_and(later_mask, later_mask, &task->cpus_allowed);
best_cpu = cpudl_find(&task_rq(task)->rd->cpudl,
task, later_mask);
if (best_cpu == -1)
@@ -1257,7 +1259,8 @@ static struct rq *find_lock_later_rq(struct task_struct *task, struct rq *rq)
if (unlikely(task_rq(task) != rq ||
!cpumask_test_cpu(later_rq->cpu,
&task->cpus_allowed) ||
- task_running(rq, task) || !task->on_rq)) {
+ task_running(rq, task) ||
+ !task_on_rq_queued(task))) {
double_unlock_balance(rq, later_rq);
later_rq = NULL;
break;
@@ -1296,7 +1299,7 @@ static struct task_struct *pick_next_pushable_dl_task(struct rq *rq)
BUG_ON(task_current(rq, p));
BUG_ON(p->nr_cpus_allowed <= 1);
- BUG_ON(!p->on_rq);
+ BUG_ON(!task_on_rq_queued(p));
BUG_ON(!dl_task(p));
return p;
@@ -1443,7 +1446,7 @@ static int pull_dl_task(struct rq *this_rq)
dl_time_before(p->dl.deadline,
this_rq->dl.earliest_dl.curr))) {
WARN_ON(p == src_rq->curr);
- WARN_ON(!p->on_rq);
+ WARN_ON(!task_on_rq_queued(p));
/*
* Then we pull iff p has actually an earlier
@@ -1569,6 +1572,8 @@ static void switched_from_dl(struct rq *rq, struct task_struct *p)
if (hrtimer_active(&p->dl.dl_timer) && !dl_policy(p->policy))
hrtimer_try_to_cancel(&p->dl.dl_timer);
+ __dl_clear_params(p);
+
#ifdef CONFIG_SMP
/*
* Since this might be the only -deadline task on the rq,
@@ -1596,7 +1601,7 @@ static void switched_to_dl(struct rq *rq, struct task_struct *p)
if (unlikely(p->dl.dl_throttled))
return;
- if (p->on_rq && rq->curr != p) {
+ if (task_on_rq_queued(p) && rq->curr != p) {
#ifdef CONFIG_SMP
if (rq->dl.overloaded && push_dl_task(rq) && rq != task_rq(p))
/* Only reschedule if pushing failed */
@@ -1614,7 +1619,7 @@ static void switched_to_dl(struct rq *rq, struct task_struct *p)
static void prio_changed_dl(struct rq *rq, struct task_struct *p,
int oldprio)
{
- if (p->on_rq || rq->curr == p) {
+ if (task_on_rq_queued(p) || rq->curr == p) {
#ifdef CONFIG_SMP
/*
* This might be too much, but unfortunately
diff --git a/kernel/sched/debug.c b/kernel/sched/debug.c
index 627b3c34b821..ce33780d8f20 100644
--- a/kernel/sched/debug.c
+++ b/kernel/sched/debug.c
@@ -150,7 +150,6 @@ print_task(struct seq_file *m, struct rq *rq, struct task_struct *p)
static void print_rq(struct seq_file *m, struct rq *rq, int rq_cpu)
{
struct task_struct *g, *p;
- unsigned long flags;
SEQ_printf(m,
"\nrunnable tasks:\n"
@@ -159,16 +158,14 @@ static void print_rq(struct seq_file *m, struct rq *rq, int rq_cpu)
"------------------------------------------------------"
"----------------------------------------------------\n");
- read_lock_irqsave(&tasklist_lock, flags);
-
- do_each_thread(g, p) {
+ rcu_read_lock();
+ for_each_process_thread(g, p) {
if (task_cpu(p) != rq_cpu)
continue;
print_task(m, rq, p);
- } while_each_thread(g, p);
-
- read_unlock_irqrestore(&tasklist_lock, flags);
+ }
+ rcu_read_unlock();
}
void print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq)
@@ -333,9 +330,7 @@ do { \
print_cfs_stats(m, cpu);
print_rt_stats(m, cpu);
- rcu_read_lock();
print_rq(m, rq, cpu);
- rcu_read_unlock();
spin_unlock_irqrestore(&sched_debug_lock, flags);
SEQ_printf(m, "\n");
}
diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
index 197d659c144c..0b069bf3e708 100644
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -23,6 +23,7 @@
#include <linux/latencytop.h>
#include <linux/sched.h>
#include <linux/cpumask.h>
+#include <linux/cpuidle.h>
#include <linux/slab.h>
#include <linux/profile.h>
#include <linux/interrupt.h>
@@ -665,6 +666,7 @@ static u64 sched_vslice(struct cfs_rq *cfs_rq, struct sched_entity *se)
}
#ifdef CONFIG_SMP
+static int select_idle_sibling(struct task_struct *p, int cpu);
static unsigned long task_h_load(struct task_struct *p);
static inline void __update_task_entity_contrib(struct sched_entity *se);
@@ -1038,7 +1040,8 @@ struct numa_stats {
*/
static void update_numa_stats(struct numa_stats *ns, int nid)
{
- int cpu, cpus = 0;
+ int smt, cpu, cpus = 0;
+ unsigned long capacity;
memset(ns, 0, sizeof(*ns));
for_each_cpu(cpu, cpumask_of_node(nid)) {
@@ -1062,8 +1065,12 @@ static void update_numa_stats(struct numa_stats *ns, int nid)
if (!cpus)
return;
- ns->task_capacity =
- DIV_ROUND_CLOSEST(ns->compute_capacity, SCHED_CAPACITY_SCALE);
+ /* smt := ceil(cpus / capacity), assumes: 1 < smt_power < 2 */
+ smt = DIV_ROUND_UP(SCHED_CAPACITY_SCALE * cpus, ns->compute_capacity);
+ capacity = cpus / smt; /* cores */
+
+ ns->task_capacity = min_t(unsigned, capacity,
+ DIV_ROUND_CLOSEST(ns->compute_capacity, SCHED_CAPACITY_SCALE));
ns->has_free_capacity = (ns->nr_running < ns->task_capacity);
}
@@ -1206,7 +1213,7 @@ static void task_numa_compare(struct task_numa_env *env,
if (!cur) {
/* Is there capacity at our destination? */
- if (env->src_stats.has_free_capacity &&
+ if (env->src_stats.nr_running <= env->src_stats.task_capacity &&
!env->dst_stats.has_free_capacity)
goto unlock;
@@ -1252,6 +1259,13 @@ balance:
if (load_too_imbalanced(src_load, dst_load, env))
goto unlock;
+ /*
+ * One idle CPU per node is evaluated for a task numa move.
+ * Call select_idle_sibling to maybe find a better one.
+ */
+ if (!cur)
+ env->dst_cpu = select_idle_sibling(env->p, env->dst_cpu);
+
assign:
task_numa_assign(env, cur, imp);
unlock:
@@ -1775,7 +1789,7 @@ void task_numa_free(struct task_struct *p)
list_del(&p->numa_entry);
grp->nr_tasks--;
spin_unlock_irqrestore(&grp->lock, flags);
- rcu_assign_pointer(p->numa_group, NULL);
+ RCU_INIT_POINTER(p->numa_group, NULL);
put_numa_group(grp);
}
@@ -1804,10 +1818,6 @@ void task_numa_fault(int last_cpupid, int mem_node, int pages, int flags)
if (!p->mm)
return;
- /* Do not worry about placement if exiting */
- if (p->state == TASK_DEAD)
- return;
-
/* Allocate buffer to track faults on a per-node basis */
if (unlikely(!p->numa_faults_memory)) {
int size = sizeof(*p->numa_faults_memory) *
@@ -1946,7 +1956,7 @@ void task_numa_work(struct callback_head *work)
vma = mm->mmap;
}
for (; vma; vma = vma->vm_next) {
- if (!vma_migratable(vma) || !vma_policy_mof(p, vma))
+ if (!vma_migratable(vma) || !vma_policy_mof(vma))
continue;
/*
@@ -2211,8 +2221,8 @@ static __always_inline u64 decay_load(u64 val, u64 n)
/*
* As y^PERIOD = 1/2, we can combine
- * y^n = 1/2^(n/PERIOD) * k^(n%PERIOD)
- * With a look-up table which covers k^n (n<PERIOD)
+ * y^n = 1/2^(n/PERIOD) * y^(n%PERIOD)
+ * With a look-up table which covers y^n (n<PERIOD)
*
* To achieve constant time decay_load.
*/
@@ -2377,6 +2387,9 @@ static inline void __update_cfs_rq_tg_load_contrib(struct cfs_rq *cfs_rq,
tg_contrib = cfs_rq->runnable_load_avg + cfs_rq->blocked_load_avg;
tg_contrib -= cfs_rq->tg_load_contrib;
+ if (!tg_contrib)
+ return;
+
if (force_update || abs(tg_contrib) > cfs_rq->tg_load_contrib / 8) {
atomic_long_add(tg_contrib, &tg->load_avg);
cfs_rq->tg_load_contrib += tg_contrib;
@@ -3892,14 +3905,6 @@ static void hrtick_start_fair(struct rq *rq, struct task_struct *p)
resched_curr(rq);
return;
}
-
- /*
- * Don't schedule slices shorter than 10000ns, that just
- * doesn't make sense. Rely on vruntime for fairness.
- */
- if (rq->curr != p)
- delta = max_t(s64, 10000LL, delta);
-
hrtick_start(rq, delta);
}
}
@@ -4087,7 +4092,7 @@ static unsigned long capacity_of(int cpu)
static unsigned long cpu_avg_load_per_task(int cpu)
{
struct rq *rq = cpu_rq(cpu);
- unsigned long nr_running = ACCESS_ONCE(rq->nr_running);
+ unsigned long nr_running = ACCESS_ONCE(rq->cfs.h_nr_running);
unsigned long load_avg = rq->cfs.runnable_load_avg;
if (nr_running)
@@ -4276,8 +4281,8 @@ static int wake_wide(struct task_struct *p)
static int wake_affine(struct sched_domain *sd, struct task_struct *p, int sync)
{
s64 this_load, load;
+ s64 this_eff_load, prev_eff_load;
int idx, this_cpu, prev_cpu;
- unsigned long tl_per_task;
struct task_group *tg;
unsigned long weight;
int balanced;
@@ -4320,47 +4325,30 @@ static int wake_affine(struct sched_domain *sd, struct task_struct *p, int sync)
* Otherwise check if either cpus are near enough in load to allow this
* task to be woken on this_cpu.
*/
- if (this_load > 0) {
- s64 this_eff_load, prev_eff_load;
+ this_eff_load = 100;
+ this_eff_load *= capacity_of(prev_cpu);
- this_eff_load = 100;
- this_eff_load *= capacity_of(prev_cpu);
+ prev_eff_load = 100 + (sd->imbalance_pct - 100) / 2;
+ prev_eff_load *= capacity_of(this_cpu);
+
+ if (this_load > 0) {
this_eff_load *= this_load +
effective_load(tg, this_cpu, weight, weight);
- prev_eff_load = 100 + (sd->imbalance_pct - 100) / 2;
- prev_eff_load *= capacity_of(this_cpu);
prev_eff_load *= load + effective_load(tg, prev_cpu, 0, weight);
+ }
- balanced = this_eff_load <= prev_eff_load;
- } else
- balanced = true;
-
- /*
- * If the currently running task will sleep within
- * a reasonable amount of time then attract this newly
- * woken task:
- */
- if (sync && balanced)
- return 1;
+ balanced = this_eff_load <= prev_eff_load;
schedstat_inc(p, se.statistics.nr_wakeups_affine_attempts);
- tl_per_task = cpu_avg_load_per_task(this_cpu);
- if (balanced ||
- (this_load <= load &&
- this_load + target_load(prev_cpu, idx) <= tl_per_task)) {
- /*
- * This domain has SD_WAKE_AFFINE and
- * p is cache cold in this domain, and
- * there is no bad imbalance.
- */
- schedstat_inc(sd, ttwu_move_affine);
- schedstat_inc(p, se.statistics.nr_wakeups_affine);
+ if (!balanced)
+ return 0;
- return 1;
- }
- return 0;
+ schedstat_inc(sd, ttwu_move_affine);
+ schedstat_inc(p, se.statistics.nr_wakeups_affine);
+
+ return 1;
}
/*
@@ -4428,20 +4416,46 @@ static int
find_idlest_cpu(struct sched_group *group, struct task_struct *p, int this_cpu)
{
unsigned long load, min_load = ULONG_MAX;
- int idlest = -1;
+ unsigned int min_exit_latency = UINT_MAX;
+ u64 latest_idle_timestamp = 0;
+ int least_loaded_cpu = this_cpu;
+ int shallowest_idle_cpu = -1;
int i;
/* Traverse only the allowed CPUs */
for_each_cpu_and(i, sched_group_cpus(group), tsk_cpus_allowed(p)) {
- load = weighted_cpuload(i);
-
- if (load < min_load || (load == min_load && i == this_cpu)) {
- min_load = load;
- idlest = i;
+ if (idle_cpu(i)) {
+ struct rq *rq = cpu_rq(i);
+ struct cpuidle_state *idle = idle_get_state(rq);
+ if (idle && idle->exit_latency < min_exit_latency) {
+ /*
+ * We give priority to a CPU whose idle state
+ * has the smallest exit latency irrespective
+ * of any idle timestamp.
+ */
+ min_exit_latency = idle->exit_latency;
+ latest_idle_timestamp = rq->idle_stamp;
+ shallowest_idle_cpu = i;
+ } else if ((!idle || idle->exit_latency == min_exit_latency) &&
+ rq->idle_stamp > latest_idle_timestamp) {
+ /*
+ * If equal or no active idle state, then
+ * the most recently idled CPU might have
+ * a warmer cache.
+ */
+ latest_idle_timestamp = rq->idle_stamp;
+ shallowest_idle_cpu = i;
+ }
+ } else {
+ load = weighted_cpuload(i);
+ if (load < min_load || (load == min_load && i == this_cpu)) {
+ min_load = load;
+ least_loaded_cpu = i;
+ }
}
}
- return idlest;
+ return shallowest_idle_cpu != -1 ? shallowest_idle_cpu : least_loaded_cpu;
}
/*
@@ -4513,11 +4527,8 @@ select_task_rq_fair(struct task_struct *p, int prev_cpu, int sd_flag, int wake_f
if (p->nr_cpus_allowed == 1)
return prev_cpu;
- if (sd_flag & SD_BALANCE_WAKE) {
- if (cpumask_test_cpu(cpu, tsk_cpus_allowed(p)))
- want_affine = 1;
- new_cpu = prev_cpu;
- }
+ if (sd_flag & SD_BALANCE_WAKE)
+ want_affine = cpumask_test_cpu(cpu, tsk_cpus_allowed(p));
rcu_read_lock();
for_each_domain(cpu, tmp) {
@@ -4704,7 +4715,7 @@ static void check_preempt_wakeup(struct rq *rq, struct task_struct *p, int wake_
return;
/*
- * This is possible from callers such as move_task(), in which we
+ * This is possible from callers such as attach_tasks(), in which we
* unconditionally check_prempt_curr() after an enqueue (which may have
* lead to a throttle). This both saves work and prevents false
* next-buddy nomination below.
@@ -5112,27 +5123,18 @@ struct lb_env {
unsigned int loop_max;
enum fbq_type fbq_type;
+ struct list_head tasks;
};
/*
- * move_task - move a task from one runqueue to another runqueue.
- * Both runqueues must be locked.
- */
-static void move_task(struct task_struct *p, struct lb_env *env)
-{
- deactivate_task(env->src_rq, p, 0);
- set_task_cpu(p, env->dst_cpu);
- activate_task(env->dst_rq, p, 0);
- check_preempt_curr(env->dst_rq, p, 0);
-}
-
-/*
* Is this task likely cache-hot:
*/
static int task_hot(struct task_struct *p, struct lb_env *env)
{
s64 delta;
+ lockdep_assert_held(&env->src_rq->lock);
+
if (p->sched_class != &fair_sched_class)
return 0;
@@ -5252,6 +5254,9 @@ static
int can_migrate_task(struct task_struct *p, struct lb_env *env)
{
int tsk_cache_hot = 0;
+
+ lockdep_assert_held(&env->src_rq->lock);
+
/*
* We do not migrate tasks that are:
* 1) throttled_lb_pair, or
@@ -5310,24 +5315,12 @@ int can_migrate_task(struct task_struct *p, struct lb_env *env)
if (!tsk_cache_hot)
tsk_cache_hot = migrate_degrades_locality(p, env);
- if (migrate_improves_locality(p, env)) {
-#ifdef CONFIG_SCHEDSTATS
+ if (migrate_improves_locality(p, env) || !tsk_cache_hot ||
+ env->sd->nr_balance_failed > env->sd->cache_nice_tries) {
if (tsk_cache_hot) {
schedstat_inc(env->sd, lb_hot_gained[env->idle]);
schedstat_inc(p, se.statistics.nr_forced_migrations);
}
-#endif
- return 1;
- }
-
- if (!tsk_cache_hot ||
- env->sd->nr_balance_failed > env->sd->cache_nice_tries) {
-
- if (tsk_cache_hot) {
- schedstat_inc(env->sd, lb_hot_gained[env->idle]);
- schedstat_inc(p, se.statistics.nr_forced_migrations);
- }
-
return 1;
}
@@ -5336,47 +5329,63 @@ int can_migrate_task(struct task_struct *p, struct lb_env *env)
}
/*
- * move_one_task tries to move exactly one task from busiest to this_rq, as
+ * detach_task() -- detach the task for the migration specified in env
+ */
+static void detach_task(struct task_struct *p, struct lb_env *env)
+{
+ lockdep_assert_held(&env->src_rq->lock);
+
+ deactivate_task(env->src_rq, p, 0);
+ p->on_rq = TASK_ON_RQ_MIGRATING;
+ set_task_cpu(p, env->dst_cpu);
+}
+
+/*
+ * detach_one_task() -- tries to dequeue exactly one task from env->src_rq, as
* part of active balancing operations within "domain".
- * Returns 1 if successful and 0 otherwise.
*
- * Called with both runqueues locked.
+ * Returns a task if successful and NULL otherwise.
*/
-static int move_one_task(struct lb_env *env)
+static struct task_struct *detach_one_task(struct lb_env *env)
{
struct task_struct *p, *n;
+ lockdep_assert_held(&env->src_rq->lock);
+
list_for_each_entry_safe(p, n, &env->src_rq->cfs_tasks, se.group_node) {
if (!can_migrate_task(p, env))
continue;
- move_task(p, env);
+ detach_task(p, env);
+
/*
- * Right now, this is only the second place move_task()
- * is called, so we can safely collect move_task()
- * stats here rather than inside move_task().
+ * Right now, this is only the second place where
+ * lb_gained[env->idle] is updated (other is detach_tasks)
+ * so we can safely collect stats here rather than
+ * inside detach_tasks().
*/
schedstat_inc(env->sd, lb_gained[env->idle]);
- return 1;
+ return p;
}
- return 0;
+ return NULL;
}
static const unsigned int sched_nr_migrate_break = 32;
/*
- * move_tasks tries to move up to imbalance weighted load from busiest to
- * this_rq, as part of a balancing operation within domain "sd".
- * Returns 1 if successful and 0 otherwise.
+ * detach_tasks() -- tries to detach up to imbalance weighted load from
+ * busiest_rq, as part of a balancing operation within domain "sd".
*
- * Called with both runqueues locked.
+ * Returns number of detached tasks if successful and 0 otherwise.
*/
-static int move_tasks(struct lb_env *env)
+static int detach_tasks(struct lb_env *env)
{
struct list_head *tasks = &env->src_rq->cfs_tasks;
struct task_struct *p;
unsigned long load;
- int pulled = 0;
+ int detached = 0;
+
+ lockdep_assert_held(&env->src_rq->lock);
if (env->imbalance <= 0)
return 0;
@@ -5407,14 +5416,16 @@ static int move_tasks(struct lb_env *env)
if ((load / 2) > env->imbalance)
goto next;
- move_task(p, env);
- pulled++;
+ detach_task(p, env);
+ list_add(&p->se.group_node, &env->tasks);
+
+ detached++;
env->imbalance -= load;
#ifdef CONFIG_PREEMPT
/*
* NEWIDLE balancing is a source of latency, so preemptible
- * kernels will stop after the first task is pulled to minimize
+ * kernels will stop after the first task is detached to minimize
* the critical section.
*/
if (env->idle == CPU_NEWLY_IDLE)
@@ -5434,13 +5445,58 @@ next:
}
/*
- * Right now, this is one of only two places move_task() is called,
- * so we can safely collect move_task() stats here rather than
- * inside move_task().
+ * Right now, this is one of only two places we collect this stat
+ * so we can safely collect detach_one_task() stats here rather
+ * than inside detach_one_task().
*/
- schedstat_add(env->sd, lb_gained[env->idle], pulled);
+ schedstat_add(env->sd, lb_gained[env->idle], detached);
+
+ return detached;
+}
+
+/*
+ * attach_task() -- attach the task detached by detach_task() to its new rq.
+ */
+static void attach_task(struct rq *rq, struct task_struct *p)
+{
+ lockdep_assert_held(&rq->lock);
+
+ BUG_ON(task_rq(p) != rq);
+ p->on_rq = TASK_ON_RQ_QUEUED;
+ activate_task(rq, p, 0);
+ check_preempt_curr(rq, p, 0);
+}
+
+/*
+ * attach_one_task() -- attaches the task returned from detach_one_task() to
+ * its new rq.
+ */
+static void attach_one_task(struct rq *rq, struct task_struct *p)
+{
+ raw_spin_lock(&rq->lock);
+ attach_task(rq, p);
+ raw_spin_unlock(&rq->lock);
+}
+
+/*
+ * attach_tasks() -- attaches all tasks detached by detach_tasks() to their
+ * new rq.
+ */
+static void attach_tasks(struct lb_env *env)
+{
+ struct list_head *tasks = &env->tasks;
+ struct task_struct *p;
+
+ raw_spin_lock(&env->dst_rq->lock);
+
+ while (!list_empty(tasks)) {
+ p = list_first_entry(tasks, struct task_struct, se.group_node);
+ list_del_init(&p->se.group_node);
- return pulled;
+ attach_task(env->dst_rq, p);
+ }
+
+ raw_spin_unlock(&env->dst_rq->lock);
}
#ifdef CONFIG_FAIR_GROUP_SCHED
@@ -5559,6 +5615,13 @@ static unsigned long task_h_load(struct task_struct *p)
#endif
/********** Helpers for find_busiest_group ************************/
+
+enum group_type {
+ group_other = 0,
+ group_imbalanced,
+ group_overloaded,
+};
+
/*
* sg_lb_stats - stats of a sched_group required for load_balancing
*/
@@ -5572,7 +5635,7 @@ struct sg_lb_stats {
unsigned int group_capacity_factor;
unsigned int idle_cpus;
unsigned int group_weight;
- int group_imb; /* Is there an imbalance in the group ? */
+ enum group_type group_type;
int group_has_free_capacity;
#ifdef CONFIG_NUMA_BALANCING
unsigned int nr_numa_running;
@@ -5610,6 +5673,8 @@ static inline void init_sd_lb_stats(struct sd_lb_stats *sds)
.total_capacity = 0UL,
.busiest_stat = {
.avg_load = 0UL,
+ .sum_nr_running = 0,
+ .group_type = group_other,
},
};
}
@@ -5652,19 +5717,17 @@ unsigned long __weak arch_scale_freq_capacity(struct sched_domain *sd, int cpu)
return default_scale_capacity(sd, cpu);
}
-static unsigned long default_scale_smt_capacity(struct sched_domain *sd, int cpu)
+static unsigned long default_scale_cpu_capacity(struct sched_domain *sd, int cpu)
{
- unsigned long weight = sd->span_weight;
- unsigned long smt_gain = sd->smt_gain;
+ if ((sd->flags & SD_SHARE_CPUCAPACITY) && (sd->span_weight > 1))
+ return sd->smt_gain / sd->span_weight;
- smt_gain /= weight;
-
- return smt_gain;
+ return SCHED_CAPACITY_SCALE;
}
-unsigned long __weak arch_scale_smt_capacity(struct sched_domain *sd, int cpu)
+unsigned long __weak arch_scale_cpu_capacity(struct sched_domain *sd, int cpu)
{
- return default_scale_smt_capacity(sd, cpu);
+ return default_scale_cpu_capacity(sd, cpu);
}
static unsigned long scale_rt_capacity(int cpu)
@@ -5703,18 +5766,15 @@ static unsigned long scale_rt_capacity(int cpu)
static void update_cpu_capacity(struct sched_domain *sd, int cpu)
{
- unsigned long weight = sd->span_weight;
unsigned long capacity = SCHED_CAPACITY_SCALE;
struct sched_group *sdg = sd->groups;
- if ((sd->flags & SD_SHARE_CPUCAPACITY) && weight > 1) {
- if (sched_feat(ARCH_CAPACITY))
- capacity *= arch_scale_smt_capacity(sd, cpu);
- else
- capacity *= default_scale_smt_capacity(sd, cpu);
+ if (sched_feat(ARCH_CAPACITY))
+ capacity *= arch_scale_cpu_capacity(sd, cpu);
+ else
+ capacity *= default_scale_cpu_capacity(sd, cpu);
- capacity >>= SCHED_CAPACITY_SHIFT;
- }
+ capacity >>= SCHED_CAPACITY_SHIFT;
sdg->sgc->capacity_orig = capacity;
@@ -5891,6 +5951,18 @@ static inline int sg_capacity_factor(struct lb_env *env, struct sched_group *gro
return capacity_factor;
}
+static enum group_type
+group_classify(struct sched_group *group, struct sg_lb_stats *sgs)
+{
+ if (sgs->sum_nr_running > sgs->group_capacity_factor)
+ return group_overloaded;
+
+ if (sg_imbalanced(group))
+ return group_imbalanced;
+
+ return group_other;
+}
+
/**
* update_sg_lb_stats - Update sched_group's statistics for load balancing.
* @env: The load balancing environment.
@@ -5920,7 +5992,7 @@ static inline void update_sg_lb_stats(struct lb_env *env,
load = source_load(i, load_idx);
sgs->group_load += load;
- sgs->sum_nr_running += rq->nr_running;
+ sgs->sum_nr_running += rq->cfs.h_nr_running;
if (rq->nr_running > 1)
*overload = true;
@@ -5942,9 +6014,8 @@ static inline void update_sg_lb_stats(struct lb_env *env,
sgs->load_per_task = sgs->sum_weighted_load / sgs->sum_nr_running;
sgs->group_weight = group->group_weight;
-
- sgs->group_imb = sg_imbalanced(group);
sgs->group_capacity_factor = sg_capacity_factor(env, group);
+ sgs->group_type = group_classify(group, sgs);
if (sgs->group_capacity_factor > sgs->sum_nr_running)
sgs->group_has_free_capacity = 1;
@@ -5968,13 +6039,19 @@ static bool update_sd_pick_busiest(struct lb_env *env,
struct sched_group *sg,
struct sg_lb_stats *sgs)
{
- if (sgs->avg_load <= sds->busiest_stat.avg_load)
- return false;
+ struct sg_lb_stats *busiest = &sds->busiest_stat;
- if (sgs->sum_nr_running > sgs->group_capacity_factor)
+ if (sgs->group_type > busiest->group_type)
return true;
- if (sgs->group_imb)
+ if (sgs->group_type < busiest->group_type)
+ return false;
+
+ if (sgs->avg_load <= busiest->avg_load)
+ return false;
+
+ /* This is the busiest node in its class. */
+ if (!(env->sd->flags & SD_ASYM_PACKING))
return true;
/*
@@ -5982,8 +6059,7 @@ static bool update_sd_pick_busiest(struct lb_env *env,
* numbered CPUs in the group, therefore mark all groups
* higher than ourself as busy.
*/
- if ((env->sd->flags & SD_ASYM_PACKING) && sgs->sum_nr_running &&
- env->dst_cpu < group_first_cpu(sg)) {
+ if (sgs->sum_nr_running && env->dst_cpu < group_first_cpu(sg)) {
if (!sds->busiest)
return true;
@@ -6228,7 +6304,7 @@ static inline void calculate_imbalance(struct lb_env *env, struct sd_lb_stats *s
local = &sds->local_stat;
busiest = &sds->busiest_stat;
- if (busiest->group_imb) {
+ if (busiest->group_type == group_imbalanced) {
/*
* In the group_imb case we cannot rely on group-wide averages
* to ensure cpu-load equilibrium, look at wider averages. XXX
@@ -6248,12 +6324,11 @@ static inline void calculate_imbalance(struct lb_env *env, struct sd_lb_stats *s
return fix_small_imbalance(env, sds);
}
- if (!busiest->group_imb) {
- /*
- * Don't want to pull so many tasks that a group would go idle.
- * Except of course for the group_imb case, since then we might
- * have to drop below capacity to reach cpu-load equilibrium.
- */
+ /*
+ * If there aren't any idle cpus, avoid creating some.
+ */
+ if (busiest->group_type == group_overloaded &&
+ local->group_type == group_overloaded) {
load_above_capacity =
(busiest->sum_nr_running - busiest->group_capacity_factor);
@@ -6337,7 +6412,7 @@ static struct sched_group *find_busiest_group(struct lb_env *env)
* work because they assume all things are equal, which typically
* isn't true due to cpus_allowed constraints and the like.
*/
- if (busiest->group_imb)
+ if (busiest->group_type == group_imbalanced)
goto force_balance;
/* SD_BALANCE_NEWIDLE trumps SMP nice when underutilized */
@@ -6346,7 +6421,7 @@ static struct sched_group *find_busiest_group(struct lb_env *env)
goto force_balance;
/*
- * If the local group is more busy than the selected busiest group
+ * If the local group is busier than the selected busiest group
* don't try and pull any tasks.
*/
if (local->avg_load >= busiest->avg_load)
@@ -6361,13 +6436,14 @@ static struct sched_group *find_busiest_group(struct lb_env *env)
if (env->idle == CPU_IDLE) {
/*
- * This cpu is idle. If the busiest group load doesn't
- * have more tasks than the number of available cpu's and
- * there is no imbalance between this and busiest group
- * wrt to idle cpu's, it is balanced.
+ * This cpu is idle. If the busiest group is not overloaded
+ * and there is no imbalance between this and busiest group
+ * wrt idle cpus, it is balanced. The imbalance becomes
+ * significant if the diff is greater than 1 otherwise we
+ * might end up to just move the imbalance on another group
*/
- if ((local->idle_cpus < busiest->idle_cpus) &&
- busiest->sum_nr_running <= busiest->group_weight)
+ if ((busiest->group_type != group_overloaded) &&
+ (local->idle_cpus <= (busiest->idle_cpus + 1)))
goto out_balanced;
} else {
/*
@@ -6550,6 +6626,7 @@ static int load_balance(int this_cpu, struct rq *this_rq,
.loop_break = sched_nr_migrate_break,
.cpus = cpus,
.fbq_type = all,
+ .tasks = LIST_HEAD_INIT(env.tasks),
};
/*
@@ -6599,23 +6676,30 @@ redo:
env.loop_max = min(sysctl_sched_nr_migrate, busiest->nr_running);
more_balance:
- local_irq_save(flags);
- double_rq_lock(env.dst_rq, busiest);
+ raw_spin_lock_irqsave(&busiest->lock, flags);
/*
* cur_ld_moved - load moved in current iteration
* ld_moved - cumulative load moved across iterations
*/
- cur_ld_moved = move_tasks(&env);
- ld_moved += cur_ld_moved;
- double_rq_unlock(env.dst_rq, busiest);
- local_irq_restore(flags);
+ cur_ld_moved = detach_tasks(&env);
/*
- * some other cpu did the load balance for us.
+ * We've detached some tasks from busiest_rq. Every
+ * task is masked "TASK_ON_RQ_MIGRATING", so we can safely
+ * unlock busiest->lock, and we are able to be sure
+ * that nobody can manipulate the tasks in parallel.
+ * See task_rq_lock() family for the details.
*/
- if (cur_ld_moved && env.dst_cpu != smp_processor_id())
- resched_cpu(env.dst_cpu);
+
+ raw_spin_unlock(&busiest->lock);
+
+ if (cur_ld_moved) {
+ attach_tasks(&env);
+ ld_moved += cur_ld_moved;
+ }
+
+ local_irq_restore(flags);
if (env.flags & LBF_NEED_BREAK) {
env.flags &= ~LBF_NEED_BREAK;
@@ -6665,10 +6749,8 @@ more_balance:
if (sd_parent) {
int *group_imbalance = &sd_parent->groups->sgc->imbalance;
- if ((env.flags & LBF_SOME_PINNED) && env.imbalance > 0) {
+ if ((env.flags & LBF_SOME_PINNED) && env.imbalance > 0)
*group_imbalance = 1;
- } else if (*group_imbalance)
- *group_imbalance = 0;
}
/* All tasks on this runqueue were pinned by CPU affinity */
@@ -6679,7 +6761,7 @@ more_balance:
env.loop_break = sched_nr_migrate_break;
goto redo;
}
- goto out_balanced;
+ goto out_all_pinned;
}
}
@@ -6744,7 +6826,7 @@ more_balance:
* If we've begun active balancing, start to back off. This
* case may not be covered by the all_pinned logic if there
* is only 1 task on the busy runqueue (because we don't call
- * move_tasks).
+ * detach_tasks).
*/
if (sd->balance_interval < sd->max_interval)
sd->balance_interval *= 2;
@@ -6753,6 +6835,23 @@ more_balance:
goto out;
out_balanced:
+ /*
+ * We reach balance although we may have faced some affinity
+ * constraints. Clear the imbalance flag if it was set.
+ */
+ if (sd_parent) {
+ int *group_imbalance = &sd_parent->groups->sgc->imbalance;
+
+ if (*group_imbalance)
+ *group_imbalance = 0;
+ }
+
+out_all_pinned:
+ /*
+ * We reach balance because all tasks are pinned at this level so
+ * we can't migrate them. Let the imbalance flag set so parent level
+ * can try to migrate them.
+ */
schedstat_inc(sd, lb_balanced[idle]);
sd->nr_balance_failed = 0;
@@ -6914,6 +7013,7 @@ static int active_load_balance_cpu_stop(void *data)
int target_cpu = busiest_rq->push_cpu;
struct rq *target_rq = cpu_rq(target_cpu);
struct sched_domain *sd;
+ struct task_struct *p = NULL;
raw_spin_lock_irq(&busiest_rq->lock);
@@ -6933,9 +7033,6 @@ static int active_load_balance_cpu_stop(void *data)
*/
BUG_ON(busiest_rq == target_rq);
- /* move a task from busiest_rq to target_rq */
- double_lock_balance(busiest_rq, target_rq);
-
/* Search for an sd spanning us and the target CPU. */
rcu_read_lock();
for_each_domain(target_cpu, sd) {
@@ -6956,16 +7053,22 @@ static int active_load_balance_cpu_stop(void *data)
schedstat_inc(sd, alb_count);
- if (move_one_task(&env))
+ p = detach_one_task(&env);
+ if (p)
schedstat_inc(sd, alb_pushed);
else
schedstat_inc(sd, alb_failed);
}
rcu_read_unlock();
- double_unlock_balance(busiest_rq, target_rq);
out_unlock:
busiest_rq->active_balance = 0;
- raw_spin_unlock_irq(&busiest_rq->lock);
+ raw_spin_unlock(&busiest_rq->lock);
+
+ if (p)
+ attach_one_task(target_rq, p);
+
+ local_irq_enable();
+
return 0;
}
@@ -7465,7 +7568,7 @@ static void task_fork_fair(struct task_struct *p)
static void
prio_changed_fair(struct rq *rq, struct task_struct *p, int oldprio)
{
- if (!p->se.on_rq)
+ if (!task_on_rq_queued(p))
return;
/*
@@ -7490,11 +7593,11 @@ static void switched_from_fair(struct rq *rq, struct task_struct *p)
* switched back to the fair class the enqueue_entity(.flags=0) will
* do the right thing.
*
- * If it's on_rq, then the dequeue_entity(.flags=0) will already
- * have normalized the vruntime, if it's !on_rq, then only when
+ * If it's queued, then the dequeue_entity(.flags=0) will already
+ * have normalized the vruntime, if it's !queued, then only when
* the task is sleeping will it still have non-normalized vruntime.
*/
- if (!p->on_rq && p->state != TASK_RUNNING) {
+ if (!task_on_rq_queued(p) && p->state != TASK_RUNNING) {
/*
* Fix up our vruntime so that the current sleep doesn't
* cause 'unlimited' sleep bonus.
@@ -7521,15 +7624,15 @@ static void switched_from_fair(struct rq *rq, struct task_struct *p)
*/
static void switched_to_fair(struct rq *rq, struct task_struct *p)
{
- struct sched_entity *se = &p->se;
#ifdef CONFIG_FAIR_GROUP_SCHED
+ struct sched_entity *se = &p->se;
/*
* Since the real-depth could have been changed (only FAIR
* class maintain depth value), reset depth properly.
*/
se->depth = se->parent ? se->parent->depth + 1 : 0;
#endif
- if (!se->on_rq)
+ if (!task_on_rq_queued(p))
return;
/*
@@ -7575,7 +7678,7 @@ void init_cfs_rq(struct cfs_rq *cfs_rq)
}
#ifdef CONFIG_FAIR_GROUP_SCHED
-static void task_move_group_fair(struct task_struct *p, int on_rq)
+static void task_move_group_fair(struct task_struct *p, int queued)
{
struct sched_entity *se = &p->se;
struct cfs_rq *cfs_rq;
@@ -7594,7 +7697,7 @@ static void task_move_group_fair(struct task_struct *p, int on_rq)
* fair sleeper stuff for the first placement, but who cares.
*/
/*
- * When !on_rq, vruntime of the task has usually NOT been normalized.
+ * When !queued, vruntime of the task has usually NOT been normalized.
* But there are some cases where it has already been normalized:
*
* - Moving a forked child which is waiting for being woken up by
@@ -7605,14 +7708,14 @@ static void task_move_group_fair(struct task_struct *p, int on_rq)
* To prevent boost or penalty in the new cfs_rq caused by delta
* min_vruntime between the two cfs_rqs, we skip vruntime adjustment.
*/
- if (!on_rq && (!se->sum_exec_runtime || p->state == TASK_WAKING))
- on_rq = 1;
+ if (!queued && (!se->sum_exec_runtime || p->state == TASK_WAKING))
+ queued = 1;
- if (!on_rq)
+ if (!queued)
se->vruntime -= cfs_rq_of(se)->min_vruntime;
set_task_rq(p, task_cpu(p));
se->depth = se->parent ? se->parent->depth + 1 : 0;
- if (!on_rq) {
+ if (!queued) {
cfs_rq = cfs_rq_of(se);
se->vruntime += cfs_rq->min_vruntime;
#ifdef CONFIG_SMP
diff --git a/kernel/sched/idle.c b/kernel/sched/idle.c
index 11e7bc434f43..c47fce75e666 100644
--- a/kernel/sched/idle.c
+++ b/kernel/sched/idle.c
@@ -147,6 +147,9 @@ use_default:
clockevents_notify(CLOCK_EVT_NOTIFY_BROADCAST_ENTER, &dev->cpu))
goto use_default;
+ /* Take note of the planned idle state. */
+ idle_set_state(this_rq(), &drv->states[next_state]);
+
/*
* Enter the idle state previously returned by the governor decision.
* This function will block until an interrupt occurs and will take
@@ -154,6 +157,9 @@ use_default:
*/
entered_state = cpuidle_enter(drv, dev, next_state);
+ /* The cpu is no longer idle or about to enter idle. */
+ idle_set_state(this_rq(), NULL);
+
if (broadcast)
clockevents_notify(CLOCK_EVT_NOTIFY_BROADCAST_EXIT, &dev->cpu);
diff --git a/kernel/sched/rt.c b/kernel/sched/rt.c
index a4c50fce9b90..d024e6ce30ba 100644
--- a/kernel/sched/rt.c
+++ b/kernel/sched/rt.c
@@ -1448,7 +1448,7 @@ pick_next_task_rt(struct rq *rq, struct task_struct *prev)
* means a dl or stop task can slip in, in which case we need
* to re-start task selection.
*/
- if (unlikely((rq->stop && rq->stop->on_rq) ||
+ if (unlikely((rq->stop && task_on_rq_queued(rq->stop)) ||
rq->dl.dl_nr_running))
return RETRY_TASK;
}
@@ -1468,8 +1468,7 @@ pick_next_task_rt(struct rq *rq, struct task_struct *prev)
p = _pick_next_task_rt(rq);
/* The running task is never eligible for pushing */
- if (p)
- dequeue_pushable_task(rq, p);
+ dequeue_pushable_task(rq, p);
set_post_schedule(rq);
@@ -1624,7 +1623,7 @@ 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) ||
- !task->on_rq)) {
+ !task_on_rq_queued(task))) {
double_unlock_balance(rq, lowest_rq);
lowest_rq = NULL;
@@ -1658,7 +1657,7 @@ static struct task_struct *pick_next_pushable_task(struct rq *rq)
BUG_ON(task_current(rq, p));
BUG_ON(p->nr_cpus_allowed <= 1);
- BUG_ON(!p->on_rq);
+ BUG_ON(!task_on_rq_queued(p));
BUG_ON(!rt_task(p));
return p;
@@ -1809,7 +1808,7 @@ static int pull_rt_task(struct rq *this_rq)
*/
if (p && (p->prio < this_rq->rt.highest_prio.curr)) {
WARN_ON(p == src_rq->curr);
- WARN_ON(!p->on_rq);
+ WARN_ON(!task_on_rq_queued(p));
/*
* There's a chance that p is higher in priority
@@ -1870,7 +1869,7 @@ static void set_cpus_allowed_rt(struct task_struct *p,
BUG_ON(!rt_task(p));
- if (!p->on_rq)
+ if (!task_on_rq_queued(p))
return;
weight = cpumask_weight(new_mask);
@@ -1936,7 +1935,7 @@ static void switched_from_rt(struct rq *rq, struct task_struct *p)
* we may need to handle the pulling of RT tasks
* now.
*/
- if (!p->on_rq || rq->rt.rt_nr_running)
+ if (!task_on_rq_queued(p) || rq->rt.rt_nr_running)
return;
if (pull_rt_task(rq))
@@ -1970,7 +1969,7 @@ static void switched_to_rt(struct rq *rq, struct task_struct *p)
* If that current running task is also an RT task
* then see if we can move to another run queue.
*/
- if (p->on_rq && rq->curr != p) {
+ if (task_on_rq_queued(p) && rq->curr != p) {
#ifdef CONFIG_SMP
if (p->nr_cpus_allowed > 1 && rq->rt.overloaded &&
/* Don't resched if we changed runqueues */
@@ -1989,7 +1988,7 @@ static void switched_to_rt(struct rq *rq, struct task_struct *p)
static void
prio_changed_rt(struct rq *rq, struct task_struct *p, int oldprio)
{
- if (!p->on_rq)
+ if (!task_on_rq_queued(p))
return;
if (rq->curr == p) {
@@ -2073,7 +2072,7 @@ static void task_tick_rt(struct rq *rq, struct task_struct *p, int queued)
for_each_sched_rt_entity(rt_se) {
if (rt_se->run_list.prev != rt_se->run_list.next) {
requeue_task_rt(rq, p, 0);
- set_tsk_need_resched(p);
+ resched_curr(rq);
return;
}
}
diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h
index 77d92f8130e8..24156c8434d1 100644
--- a/kernel/sched/sched.h
+++ b/kernel/sched/sched.h
@@ -14,6 +14,11 @@
#include "cpuacct.h"
struct rq;
+struct cpuidle_state;
+
+/* task_struct::on_rq states: */
+#define TASK_ON_RQ_QUEUED 1
+#define TASK_ON_RQ_MIGRATING 2
extern __read_mostly int scheduler_running;
@@ -126,6 +131,9 @@ struct rt_bandwidth {
u64 rt_runtime;
struct hrtimer rt_period_timer;
};
+
+void __dl_clear_params(struct task_struct *p);
+
/*
* To keep the bandwidth of -deadline tasks and groups under control
* we need some place where:
@@ -184,7 +192,7 @@ struct cfs_bandwidth {
raw_spinlock_t lock;
ktime_t period;
u64 quota, runtime;
- s64 hierarchal_quota;
+ s64 hierarchical_quota;
u64 runtime_expires;
int idle, timer_active;
@@ -636,6 +644,11 @@ struct rq {
#ifdef CONFIG_SMP
struct llist_head wake_list;
#endif
+
+#ifdef CONFIG_CPU_IDLE
+ /* Must be inspected within a rcu lock section */
+ struct cpuidle_state *idle_state;
+#endif
};
static inline int cpu_of(struct rq *rq)
@@ -647,7 +660,7 @@ static inline int cpu_of(struct rq *rq)
#endif
}
-DECLARE_PER_CPU(struct rq, runqueues);
+DECLARE_PER_CPU_SHARED_ALIGNED(struct rq, runqueues);
#define cpu_rq(cpu) (&per_cpu(runqueues, (cpu)))
#define this_rq() this_cpu_ptr(&runqueues)
@@ -942,6 +955,15 @@ static inline int task_running(struct rq *rq, struct task_struct *p)
#endif
}
+static inline int task_on_rq_queued(struct task_struct *p)
+{
+ return p->on_rq == TASK_ON_RQ_QUEUED;
+}
+
+static inline int task_on_rq_migrating(struct task_struct *p)
+{
+ return p->on_rq == TASK_ON_RQ_MIGRATING;
+}
#ifndef prepare_arch_switch
# define prepare_arch_switch(next) do { } while (0)
@@ -953,7 +975,6 @@ static inline int task_running(struct rq *rq, struct task_struct *p)
# define finish_arch_post_lock_switch() do { } while (0)
#endif
-#ifndef __ARCH_WANT_UNLOCKED_CTXSW
static inline void prepare_lock_switch(struct rq *rq, struct task_struct *next)
{
#ifdef CONFIG_SMP
@@ -991,35 +1012,6 @@ static inline void finish_lock_switch(struct rq *rq, struct task_struct *prev)
raw_spin_unlock_irq(&rq->lock);
}
-#else /* __ARCH_WANT_UNLOCKED_CTXSW */
-static inline void prepare_lock_switch(struct rq *rq, struct task_struct *next)
-{
-#ifdef CONFIG_SMP
- /*
- * We can optimise this out completely for !SMP, because the
- * SMP rebalancing from interrupt is the only thing that cares
- * here.
- */
- next->on_cpu = 1;
-#endif
- raw_spin_unlock(&rq->lock);
-}
-
-static inline void finish_lock_switch(struct rq *rq, struct task_struct *prev)
-{
-#ifdef CONFIG_SMP
- /*
- * After ->on_cpu is cleared, the task can be moved to a different CPU.
- * We must ensure this doesn't happen until the switch is completely
- * finished.
- */
- smp_wmb();
- prev->on_cpu = 0;
-#endif
- local_irq_enable();
-}
-#endif /* __ARCH_WANT_UNLOCKED_CTXSW */
-
/*
* wake flags
*/
@@ -1180,6 +1172,30 @@ static inline void idle_exit_fair(struct rq *rq) { }
#endif
+#ifdef CONFIG_CPU_IDLE
+static inline void idle_set_state(struct rq *rq,
+ struct cpuidle_state *idle_state)
+{
+ rq->idle_state = idle_state;
+}
+
+static inline struct cpuidle_state *idle_get_state(struct rq *rq)
+{
+ WARN_ON(!rcu_read_lock_held());
+ return rq->idle_state;
+}
+#else
+static inline void idle_set_state(struct rq *rq,
+ struct cpuidle_state *idle_state)
+{
+}
+
+static inline struct cpuidle_state *idle_get_state(struct rq *rq)
+{
+ return NULL;
+}
+#endif
+
extern void sysrq_sched_debug_show(void);
extern void sched_init_granularity(void);
extern void update_max_interval(void);
diff --git a/kernel/sched/stop_task.c b/kernel/sched/stop_task.c
index bfe0edadbfbb..67426e529f59 100644
--- a/kernel/sched/stop_task.c
+++ b/kernel/sched/stop_task.c
@@ -28,7 +28,7 @@ pick_next_task_stop(struct rq *rq, struct task_struct *prev)
{
struct task_struct *stop = rq->stop;
- if (!stop || !stop->on_rq)
+ if (!stop || !task_on_rq_queued(stop))
return NULL;
put_prev_task(rq, prev);
diff --git a/kernel/sched/wait.c b/kernel/sched/wait.c
index 15cab1a4f84e..5a62915f47a8 100644
--- a/kernel/sched/wait.c
+++ b/kernel/sched/wait.c
@@ -343,6 +343,18 @@ int __sched out_of_line_wait_on_bit(void *word, int bit,
}
EXPORT_SYMBOL(out_of_line_wait_on_bit);
+int __sched out_of_line_wait_on_bit_timeout(
+ void *word, int bit, wait_bit_action_f *action,
+ unsigned mode, unsigned long timeout)
+{
+ wait_queue_head_t *wq = bit_waitqueue(word, bit);
+ DEFINE_WAIT_BIT(wait, word, bit);
+
+ wait.key.timeout = jiffies + timeout;
+ return __wait_on_bit(wq, &wait, action, mode);
+}
+EXPORT_SYMBOL_GPL(out_of_line_wait_on_bit_timeout);
+
int __sched
__wait_on_bit_lock(wait_queue_head_t *wq, struct wait_bit_queue *q,
wait_bit_action_f *action, unsigned mode)
@@ -520,3 +532,27 @@ __sched int bit_wait_io(struct wait_bit_key *word)
return 0;
}
EXPORT_SYMBOL(bit_wait_io);
+
+__sched int bit_wait_timeout(struct wait_bit_key *word)
+{
+ unsigned long now = ACCESS_ONCE(jiffies);
+ if (signal_pending_state(current->state, current))
+ return 1;
+ if (time_after_eq(now, word->timeout))
+ return -EAGAIN;
+ schedule_timeout(word->timeout - now);
+ return 0;
+}
+EXPORT_SYMBOL_GPL(bit_wait_timeout);
+
+__sched int bit_wait_io_timeout(struct wait_bit_key *word)
+{
+ unsigned long now = ACCESS_ONCE(jiffies);
+ if (signal_pending_state(current->state, current))
+ return 1;
+ if (time_after_eq(now, word->timeout))
+ return -EAGAIN;
+ io_schedule_timeout(word->timeout - now);
+ return 0;
+}
+EXPORT_SYMBOL_GPL(bit_wait_io_timeout);
diff --git a/kernel/seccomp.c b/kernel/seccomp.c
index 44eb005c6695..4ef9687ac115 100644
--- a/kernel/seccomp.c
+++ b/kernel/seccomp.c
@@ -21,10 +21,11 @@
#include <linux/slab.h>
#include <linux/syscalls.h>
-/* #define SECCOMP_DEBUG 1 */
+#ifdef CONFIG_HAVE_ARCH_SECCOMP_FILTER
+#include <asm/syscall.h>
+#endif
#ifdef CONFIG_SECCOMP_FILTER
-#include <asm/syscall.h>
#include <linux/filter.h>
#include <linux/pid.h>
#include <linux/ptrace.h>
@@ -172,10 +173,10 @@ static int seccomp_check_filter(struct sock_filter *filter, unsigned int flen)
*
* Returns valid seccomp BPF response codes.
*/
-static u32 seccomp_run_filters(int syscall)
+static u32 seccomp_run_filters(struct seccomp_data *sd)
{
struct seccomp_filter *f = ACCESS_ONCE(current->seccomp.filter);
- struct seccomp_data sd;
+ struct seccomp_data sd_local;
u32 ret = SECCOMP_RET_ALLOW;
/* Ensure unexpected behavior doesn't result in failing open. */
@@ -185,14 +186,17 @@ static u32 seccomp_run_filters(int syscall)
/* Make sure cross-thread synced filter points somewhere sane. */
smp_read_barrier_depends();
- populate_seccomp_data(&sd);
+ if (!sd) {
+ populate_seccomp_data(&sd_local);
+ sd = &sd_local;
+ }
/*
* All filters in the list are evaluated and the lowest BPF return
* value always takes priority (ignoring the DATA).
*/
for (; f; f = f->prev) {
- u32 cur_ret = BPF_PROG_RUN(f->prog, (void *)&sd);
+ u32 cur_ret = BPF_PROG_RUN(f->prog, (void *)sd);
if ((cur_ret & SECCOMP_RET_ACTION) < (ret & SECCOMP_RET_ACTION))
ret = cur_ret;
@@ -395,16 +399,15 @@ static struct seccomp_filter *seccomp_prepare_filter(struct sock_fprog *fprog)
if (!filter)
goto free_prog;
- filter->prog = kzalloc(bpf_prog_size(new_len),
- GFP_KERNEL|__GFP_NOWARN);
+ filter->prog = bpf_prog_alloc(bpf_prog_size(new_len), __GFP_NOWARN);
if (!filter->prog)
goto free_filter;
ret = bpf_convert_filter(fp, fprog->len, filter->prog->insnsi, &new_len);
if (ret)
goto free_filter_prog;
- kfree(fp);
+ kfree(fp);
atomic_set(&filter->usage, 1);
filter->prog->len = new_len;
@@ -413,7 +416,7 @@ static struct seccomp_filter *seccomp_prepare_filter(struct sock_fprog *fprog)
return filter;
free_filter_prog:
- kfree(filter->prog);
+ __bpf_prog_free(filter->prog);
free_filter:
kfree(filter);
free_prog:
@@ -564,11 +567,55 @@ static int mode1_syscalls_32[] = {
};
#endif
-int __secure_computing(int this_syscall)
+static void __secure_computing_strict(int this_syscall)
+{
+ int *syscall_whitelist = mode1_syscalls;
+#ifdef CONFIG_COMPAT
+ if (is_compat_task())
+ syscall_whitelist = mode1_syscalls_32;
+#endif
+ do {
+ if (*syscall_whitelist == this_syscall)
+ return;
+ } while (*++syscall_whitelist);
+
+#ifdef SECCOMP_DEBUG
+ dump_stack();
+#endif
+ audit_seccomp(this_syscall, SIGKILL, SECCOMP_RET_KILL);
+ do_exit(SIGKILL);
+}
+
+#ifndef CONFIG_HAVE_ARCH_SECCOMP_FILTER
+void secure_computing_strict(int this_syscall)
+{
+ int mode = current->seccomp.mode;
+
+ if (mode == 0)
+ return;
+ else if (mode == SECCOMP_MODE_STRICT)
+ __secure_computing_strict(this_syscall);
+ else
+ BUG();
+}
+#else
+int __secure_computing(void)
+{
+ u32 phase1_result = seccomp_phase1(NULL);
+
+ if (likely(phase1_result == SECCOMP_PHASE1_OK))
+ return 0;
+ else if (likely(phase1_result == SECCOMP_PHASE1_SKIP))
+ return -1;
+ else
+ return seccomp_phase2(phase1_result);
+}
+
+#ifdef CONFIG_SECCOMP_FILTER
+static u32 __seccomp_phase1_filter(int this_syscall, struct seccomp_data *sd)
{
- int exit_sig = 0;
- int *syscall;
- u32 ret;
+ u32 filter_ret, action;
+ int data;
/*
* Make sure that any changes to mode from another thread have
@@ -576,85 +623,127 @@ int __secure_computing(int this_syscall)
*/
rmb();
- switch (current->seccomp.mode) {
- case SECCOMP_MODE_STRICT:
- syscall = mode1_syscalls;
-#ifdef CONFIG_COMPAT
- if (is_compat_task())
- syscall = mode1_syscalls_32;
+ filter_ret = seccomp_run_filters(sd);
+ data = filter_ret & SECCOMP_RET_DATA;
+ action = filter_ret & SECCOMP_RET_ACTION;
+
+ switch (action) {
+ case SECCOMP_RET_ERRNO:
+ /* Set the low-order 16-bits as a errno. */
+ syscall_set_return_value(current, task_pt_regs(current),
+ -data, 0);
+ goto skip;
+
+ case SECCOMP_RET_TRAP:
+ /* Show the handler the original registers. */
+ syscall_rollback(current, task_pt_regs(current));
+ /* Let the filter pass back 16 bits of data. */
+ seccomp_send_sigsys(this_syscall, data);
+ goto skip;
+
+ case SECCOMP_RET_TRACE:
+ return filter_ret; /* Save the rest for phase 2. */
+
+ case SECCOMP_RET_ALLOW:
+ return SECCOMP_PHASE1_OK;
+
+ case SECCOMP_RET_KILL:
+ default:
+ audit_seccomp(this_syscall, SIGSYS, action);
+ do_exit(SIGSYS);
+ }
+
+ unreachable();
+
+skip:
+ audit_seccomp(this_syscall, 0, action);
+ return SECCOMP_PHASE1_SKIP;
+}
#endif
- do {
- if (*syscall == this_syscall)
- return 0;
- } while (*++syscall);
- exit_sig = SIGKILL;
- ret = SECCOMP_RET_KILL;
- break;
+
+/**
+ * seccomp_phase1() - run fast path seccomp checks on the current syscall
+ * @arg sd: The seccomp_data or NULL
+ *
+ * This only reads pt_regs via the syscall_xyz helpers. The only change
+ * it will make to pt_regs is via syscall_set_return_value, and it will
+ * only do that if it returns SECCOMP_PHASE1_SKIP.
+ *
+ * If sd is provided, it will not read pt_regs at all.
+ *
+ * It may also call do_exit or force a signal; these actions must be
+ * safe.
+ *
+ * If it returns SECCOMP_PHASE1_OK, the syscall passes checks and should
+ * be processed normally.
+ *
+ * If it returns SECCOMP_PHASE1_SKIP, then the syscall should not be
+ * invoked. In this case, seccomp_phase1 will have set the return value
+ * using syscall_set_return_value.
+ *
+ * If it returns anything else, then the return value should be passed
+ * to seccomp_phase2 from a context in which ptrace hooks are safe.
+ */
+u32 seccomp_phase1(struct seccomp_data *sd)
+{
+ int mode = current->seccomp.mode;
+ int this_syscall = sd ? sd->nr :
+ syscall_get_nr(current, task_pt_regs(current));
+
+ switch (mode) {
+ case SECCOMP_MODE_STRICT:
+ __secure_computing_strict(this_syscall); /* may call do_exit */
+ return SECCOMP_PHASE1_OK;
#ifdef CONFIG_SECCOMP_FILTER
- case SECCOMP_MODE_FILTER: {
- int data;
- struct pt_regs *regs = task_pt_regs(current);
- ret = seccomp_run_filters(this_syscall);
- data = ret & SECCOMP_RET_DATA;
- ret &= SECCOMP_RET_ACTION;
- switch (ret) {
- case SECCOMP_RET_ERRNO:
- /* Set the low-order 16-bits as a errno. */
- syscall_set_return_value(current, regs,
- -data, 0);
- goto skip;
- case SECCOMP_RET_TRAP:
- /* Show the handler the original registers. */
- syscall_rollback(current, regs);
- /* Let the filter pass back 16 bits of data. */
- seccomp_send_sigsys(this_syscall, data);
- goto skip;
- case SECCOMP_RET_TRACE:
- /* Skip these calls if there is no tracer. */
- if (!ptrace_event_enabled(current, PTRACE_EVENT_SECCOMP)) {
- syscall_set_return_value(current, regs,
- -ENOSYS, 0);
- goto skip;
- }
- /* Allow the BPF to provide the event message */
- ptrace_event(PTRACE_EVENT_SECCOMP, data);
- /*
- * The delivery of a fatal signal during event
- * notification may silently skip tracer notification.
- * Terminating the task now avoids executing a system
- * call that may not be intended.
- */
- if (fatal_signal_pending(current))
- break;
- if (syscall_get_nr(current, regs) < 0)
- goto skip; /* Explicit request to skip. */
-
- return 0;
- case SECCOMP_RET_ALLOW:
- return 0;
- case SECCOMP_RET_KILL:
- default:
- break;
- }
- exit_sig = SIGSYS;
- break;
- }
+ case SECCOMP_MODE_FILTER:
+ return __seccomp_phase1_filter(this_syscall, sd);
#endif
default:
BUG();
}
+}
-#ifdef SECCOMP_DEBUG
- dump_stack();
-#endif
- audit_seccomp(this_syscall, exit_sig, ret);
- do_exit(exit_sig);
-#ifdef CONFIG_SECCOMP_FILTER
-skip:
- audit_seccomp(this_syscall, exit_sig, ret);
-#endif
- return -1;
+/**
+ * seccomp_phase2() - finish slow path seccomp work for the current syscall
+ * @phase1_result: The return value from seccomp_phase1()
+ *
+ * This must be called from a context in which ptrace hooks can be used.
+ *
+ * Returns 0 if the syscall should be processed or -1 to skip the syscall.
+ */
+int seccomp_phase2(u32 phase1_result)
+{
+ struct pt_regs *regs = task_pt_regs(current);
+ u32 action = phase1_result & SECCOMP_RET_ACTION;
+ int data = phase1_result & SECCOMP_RET_DATA;
+
+ BUG_ON(action != SECCOMP_RET_TRACE);
+
+ audit_seccomp(syscall_get_nr(current, regs), 0, action);
+
+ /* Skip these calls if there is no tracer. */
+ if (!ptrace_event_enabled(current, PTRACE_EVENT_SECCOMP)) {
+ syscall_set_return_value(current, regs,
+ -ENOSYS, 0);
+ return -1;
+ }
+
+ /* Allow the BPF to provide the event message */
+ ptrace_event(PTRACE_EVENT_SECCOMP, data);
+ /*
+ * The delivery of a fatal signal during event
+ * notification may silently skip tracer notification.
+ * Terminating the task now avoids executing a system
+ * call that may not be intended.
+ */
+ if (fatal_signal_pending(current))
+ do_exit(SIGSYS);
+ if (syscall_get_nr(current, regs) < 0)
+ return -1; /* Explicit request to skip. */
+
+ return 0;
}
+#endif /* CONFIG_HAVE_ARCH_SECCOMP_FILTER */
long prctl_get_seccomp(void)
{
diff --git a/kernel/smp.c b/kernel/smp.c
index af24183fe6bb..f38a1e692259 100644
--- a/kernel/smp.c
+++ b/kernel/smp.c
@@ -13,6 +13,7 @@
#include <linux/gfp.h>
#include <linux/smp.h>
#include <linux/cpu.h>
+#include <linux/sched.h>
#include "smpboot.h"
@@ -699,3 +700,24 @@ void kick_all_cpus_sync(void)
smp_call_function(do_nothing, NULL, 1);
}
EXPORT_SYMBOL_GPL(kick_all_cpus_sync);
+
+/**
+ * wake_up_all_idle_cpus - break all cpus out of idle
+ * wake_up_all_idle_cpus try to break all cpus which is in idle state even
+ * including idle polling cpus, for non-idle cpus, we will do nothing
+ * for them.
+ */
+void wake_up_all_idle_cpus(void)
+{
+ int cpu;
+
+ preempt_disable();
+ for_each_online_cpu(cpu) {
+ if (cpu == smp_processor_id())
+ continue;
+
+ wake_up_if_idle(cpu);
+ }
+ preempt_enable();
+}
+EXPORT_SYMBOL_GPL(wake_up_all_idle_cpus);
diff --git a/kernel/softirq.c b/kernel/softirq.c
index 2d44b5714fe6..0699add19164 100644
--- a/kernel/softirq.c
+++ b/kernel/softirq.c
@@ -278,7 +278,7 @@ restart:
pending >>= softirq_bit;
}
- rcu_bh_qs(smp_processor_id());
+ rcu_bh_qs();
local_irq_disable();
pending = local_softirq_pending();
diff --git a/kernel/sys.c b/kernel/sys.c
index ce8129192a26..1eaa2f0b0246 100644
--- a/kernel/sys.c
+++ b/kernel/sys.c
@@ -62,28 +62,28 @@
#include <asm/unistd.h>
#ifndef SET_UNALIGN_CTL
-# define SET_UNALIGN_CTL(a,b) (-EINVAL)
+# define SET_UNALIGN_CTL(a, b) (-EINVAL)
#endif
#ifndef GET_UNALIGN_CTL
-# define GET_UNALIGN_CTL(a,b) (-EINVAL)
+# define GET_UNALIGN_CTL(a, b) (-EINVAL)
#endif
#ifndef SET_FPEMU_CTL
-# define SET_FPEMU_CTL(a,b) (-EINVAL)
+# define SET_FPEMU_CTL(a, b) (-EINVAL)
#endif
#ifndef GET_FPEMU_CTL
-# define GET_FPEMU_CTL(a,b) (-EINVAL)
+# define GET_FPEMU_CTL(a, b) (-EINVAL)
#endif
#ifndef SET_FPEXC_CTL
-# define SET_FPEXC_CTL(a,b) (-EINVAL)
+# define SET_FPEXC_CTL(a, b) (-EINVAL)
#endif
#ifndef GET_FPEXC_CTL
-# define GET_FPEXC_CTL(a,b) (-EINVAL)
+# define GET_FPEXC_CTL(a, b) (-EINVAL)
#endif
#ifndef GET_ENDIAN
-# define GET_ENDIAN(a,b) (-EINVAL)
+# define GET_ENDIAN(a, b) (-EINVAL)
#endif
#ifndef SET_ENDIAN
-# define SET_ENDIAN(a,b) (-EINVAL)
+# define SET_ENDIAN(a, b) (-EINVAL)
#endif
#ifndef GET_TSC_CTL
# define GET_TSC_CTL(a) (-EINVAL)
@@ -182,39 +182,40 @@ SYSCALL_DEFINE3(setpriority, int, which, int, who, int, niceval)
rcu_read_lock();
read_lock(&tasklist_lock);
switch (which) {
- case PRIO_PROCESS:
- if (who)
- p = find_task_by_vpid(who);
- else
- p = current;
- if (p)
- error = set_one_prio(p, niceval, error);
- break;
- case PRIO_PGRP:
- if (who)
- pgrp = find_vpid(who);
- else
- pgrp = task_pgrp(current);
- do_each_pid_thread(pgrp, PIDTYPE_PGID, p) {
- error = set_one_prio(p, niceval, error);
- } while_each_pid_thread(pgrp, PIDTYPE_PGID, p);
- break;
- case PRIO_USER:
- uid = make_kuid(cred->user_ns, who);
- user = cred->user;
- if (!who)
- uid = cred->uid;
- else if (!uid_eq(uid, cred->uid) &&
- !(user = find_user(uid)))
+ case PRIO_PROCESS:
+ if (who)
+ p = find_task_by_vpid(who);
+ else
+ p = current;
+ if (p)
+ error = set_one_prio(p, niceval, error);
+ break;
+ case PRIO_PGRP:
+ if (who)
+ pgrp = find_vpid(who);
+ else
+ pgrp = task_pgrp(current);
+ do_each_pid_thread(pgrp, PIDTYPE_PGID, p) {
+ error = set_one_prio(p, niceval, error);
+ } while_each_pid_thread(pgrp, PIDTYPE_PGID, p);
+ break;
+ case PRIO_USER:
+ uid = make_kuid(cred->user_ns, who);
+ user = cred->user;
+ if (!who)
+ uid = cred->uid;
+ else if (!uid_eq(uid, cred->uid)) {
+ user = find_user(uid);
+ if (!user)
goto out_unlock; /* No processes for this user */
-
- do_each_thread(g, p) {
- if (uid_eq(task_uid(p), uid))
- error = set_one_prio(p, niceval, error);
- } while_each_thread(g, p);
- if (!uid_eq(uid, cred->uid))
- free_uid(user); /* For find_user() */
- break;
+ }
+ do_each_thread(g, p) {
+ if (uid_eq(task_uid(p), uid))
+ error = set_one_prio(p, niceval, error);
+ } while_each_thread(g, p);
+ if (!uid_eq(uid, cred->uid))
+ free_uid(user); /* For find_user() */
+ break;
}
out_unlock:
read_unlock(&tasklist_lock);
@@ -244,47 +245,48 @@ SYSCALL_DEFINE2(getpriority, int, which, int, who)
rcu_read_lock();
read_lock(&tasklist_lock);
switch (which) {
- case PRIO_PROCESS:
- if (who)
- p = find_task_by_vpid(who);
- else
- p = current;
- if (p) {
+ case PRIO_PROCESS:
+ if (who)
+ p = find_task_by_vpid(who);
+ else
+ p = current;
+ if (p) {
+ niceval = nice_to_rlimit(task_nice(p));
+ if (niceval > retval)
+ retval = niceval;
+ }
+ break;
+ case PRIO_PGRP:
+ if (who)
+ pgrp = find_vpid(who);
+ else
+ pgrp = task_pgrp(current);
+ do_each_pid_thread(pgrp, PIDTYPE_PGID, p) {
+ niceval = nice_to_rlimit(task_nice(p));
+ if (niceval > retval)
+ retval = niceval;
+ } while_each_pid_thread(pgrp, PIDTYPE_PGID, p);
+ break;
+ case PRIO_USER:
+ uid = make_kuid(cred->user_ns, who);
+ user = cred->user;
+ if (!who)
+ uid = cred->uid;
+ else if (!uid_eq(uid, cred->uid)) {
+ user = find_user(uid);
+ if (!user)
+ goto out_unlock; /* No processes for this user */
+ }
+ do_each_thread(g, p) {
+ if (uid_eq(task_uid(p), uid)) {
niceval = nice_to_rlimit(task_nice(p));
if (niceval > retval)
retval = niceval;
}
- break;
- case PRIO_PGRP:
- if (who)
- pgrp = find_vpid(who);
- else
- pgrp = task_pgrp(current);
- do_each_pid_thread(pgrp, PIDTYPE_PGID, p) {
- niceval = nice_to_rlimit(task_nice(p));
- if (niceval > retval)
- retval = niceval;
- } while_each_pid_thread(pgrp, PIDTYPE_PGID, p);
- break;
- case PRIO_USER:
- uid = make_kuid(cred->user_ns, who);
- user = cred->user;
- if (!who)
- uid = cred->uid;
- else if (!uid_eq(uid, cred->uid) &&
- !(user = find_user(uid)))
- goto out_unlock; /* No processes for this user */
-
- do_each_thread(g, p) {
- if (uid_eq(task_uid(p), uid)) {
- niceval = nice_to_rlimit(task_nice(p));
- if (niceval > retval)
- retval = niceval;
- }
- } while_each_thread(g, p);
- if (!uid_eq(uid, cred->uid))
- free_uid(user); /* for find_user() */
- break;
+ } while_each_thread(g, p);
+ if (!uid_eq(uid, cred->uid))
+ free_uid(user); /* for find_user() */
+ break;
}
out_unlock:
read_unlock(&tasklist_lock);
@@ -306,7 +308,7 @@ out_unlock:
*
* The general idea is that a program which uses just setregid() will be
* 100% compatible with BSD. A program which uses just setgid() will be
- * 100% compatible with POSIX with saved IDs.
+ * 100% compatible with POSIX with saved IDs.
*
* SMP: There are not races, the GIDs are checked only by filesystem
* operations (as far as semantic preservation is concerned).
@@ -364,7 +366,7 @@ error:
}
/*
- * setgid() is implemented like SysV w/ SAVED_IDS
+ * setgid() is implemented like SysV w/ SAVED_IDS
*
* SMP: Same implicit races as above.
*/
@@ -442,7 +444,7 @@ static int set_user(struct cred *new)
*
* The general idea is that a program which uses just setreuid() will be
* 100% compatible with BSD. A program which uses just setuid() will be
- * 100% compatible with POSIX with saved IDs.
+ * 100% compatible with POSIX with saved IDs.
*/
SYSCALL_DEFINE2(setreuid, uid_t, ruid, uid_t, euid)
{
@@ -503,17 +505,17 @@ error:
abort_creds(new);
return retval;
}
-
+
/*
- * setuid() is implemented like SysV with SAVED_IDS
- *
+ * setuid() is implemented like SysV with SAVED_IDS
+ *
* Note that SAVED_ID's is deficient in that a setuid root program
- * like sendmail, for example, cannot set its uid to be a normal
+ * like sendmail, for example, cannot set its uid to be a normal
* user and then switch back, because if you're root, setuid() sets
* the saved uid too. If you don't like this, blame the bright people
* in the POSIX committee and/or USG. Note that the BSD-style setreuid()
* will allow a root program to temporarily drop privileges and be able to
- * regain them by swapping the real and effective uid.
+ * regain them by swapping the real and effective uid.
*/
SYSCALL_DEFINE1(setuid, uid_t, uid)
{
@@ -637,10 +639,12 @@ SYSCALL_DEFINE3(getresuid, uid_t __user *, ruidp, uid_t __user *, euidp, uid_t _
euid = from_kuid_munged(cred->user_ns, cred->euid);
suid = from_kuid_munged(cred->user_ns, cred->suid);
- if (!(retval = put_user(ruid, ruidp)) &&
- !(retval = put_user(euid, euidp)))
- retval = put_user(suid, suidp);
-
+ retval = put_user(ruid, ruidp);
+ if (!retval) {
+ retval = put_user(euid, euidp);
+ if (!retval)
+ return put_user(suid, suidp);
+ }
return retval;
}
@@ -709,9 +713,12 @@ SYSCALL_DEFINE3(getresgid, gid_t __user *, rgidp, gid_t __user *, egidp, gid_t _
egid = from_kgid_munged(cred->user_ns, cred->egid);
sgid = from_kgid_munged(cred->user_ns, cred->sgid);
- if (!(retval = put_user(rgid, rgidp)) &&
- !(retval = put_user(egid, egidp)))
- retval = put_user(sgid, sgidp);
+ retval = put_user(rgid, rgidp);
+ if (!retval) {
+ retval = put_user(egid, egidp);
+ if (!retval)
+ retval = put_user(sgid, sgidp);
+ }
return retval;
}
@@ -862,11 +869,9 @@ void do_sys_times(struct tms *tms)
{
cputime_t tgutime, tgstime, cutime, cstime;
- spin_lock_irq(&current->sighand->siglock);
thread_group_cputime_adjusted(current, &tgutime, &tgstime);
cutime = current->signal->cutime;
cstime = current->signal->cstime;
- spin_unlock_irq(&current->sighand->siglock);
tms->tms_utime = cputime_to_clock_t(tgutime);
tms->tms_stime = cputime_to_clock_t(tgstime);
tms->tms_cutime = cputime_to_clock_t(cutime);
@@ -1284,7 +1289,6 @@ SYSCALL_DEFINE2(getrlimit, unsigned int, resource, struct rlimit __user *, rlim)
/*
* Back compatibility for getrlimit. Needed for some apps.
*/
-
SYSCALL_DEFINE2(old_getrlimit, unsigned int, resource,
struct rlimit __user *, rlim)
{
@@ -1299,7 +1303,7 @@ SYSCALL_DEFINE2(old_getrlimit, unsigned int, resource,
x.rlim_cur = 0x7FFFFFFF;
if (x.rlim_max > 0x7FFFFFFF)
x.rlim_max = 0x7FFFFFFF;
- return copy_to_user(rlim, &x, sizeof(x))?-EFAULT:0;
+ return copy_to_user(rlim, &x, sizeof(x)) ? -EFAULT : 0;
}
#endif
@@ -1527,7 +1531,7 @@ static void k_getrusage(struct task_struct *p, int who, struct rusage *r)
cputime_t tgutime, tgstime, utime, stime;
unsigned long maxrss = 0;
- memset((char *) r, 0, sizeof *r);
+ memset((char *)r, 0, sizeof (*r));
utime = stime = 0;
if (who == RUSAGE_THREAD) {
@@ -1541,41 +1545,41 @@ static void k_getrusage(struct task_struct *p, int who, struct rusage *r)
return;
switch (who) {
- case RUSAGE_BOTH:
- case RUSAGE_CHILDREN:
- utime = p->signal->cutime;
- stime = p->signal->cstime;
- r->ru_nvcsw = p->signal->cnvcsw;
- r->ru_nivcsw = p->signal->cnivcsw;
- r->ru_minflt = p->signal->cmin_flt;
- r->ru_majflt = p->signal->cmaj_flt;
- r->ru_inblock = p->signal->cinblock;
- r->ru_oublock = p->signal->coublock;
- maxrss = p->signal->cmaxrss;
-
- if (who == RUSAGE_CHILDREN)
- break;
-
- case RUSAGE_SELF:
- thread_group_cputime_adjusted(p, &tgutime, &tgstime);
- utime += tgutime;
- stime += tgstime;
- r->ru_nvcsw += p->signal->nvcsw;
- r->ru_nivcsw += p->signal->nivcsw;
- r->ru_minflt += p->signal->min_flt;
- r->ru_majflt += p->signal->maj_flt;
- r->ru_inblock += p->signal->inblock;
- r->ru_oublock += p->signal->oublock;
- if (maxrss < p->signal->maxrss)
- maxrss = p->signal->maxrss;
- t = p;
- do {
- accumulate_thread_rusage(t, r);
- } while_each_thread(p, t);
+ case RUSAGE_BOTH:
+ case RUSAGE_CHILDREN:
+ utime = p->signal->cutime;
+ stime = p->signal->cstime;
+ r->ru_nvcsw = p->signal->cnvcsw;
+ r->ru_nivcsw = p->signal->cnivcsw;
+ r->ru_minflt = p->signal->cmin_flt;
+ r->ru_majflt = p->signal->cmaj_flt;
+ r->ru_inblock = p->signal->cinblock;
+ r->ru_oublock = p->signal->coublock;
+ maxrss = p->signal->cmaxrss;
+
+ if (who == RUSAGE_CHILDREN)
break;
- default:
- BUG();
+ case RUSAGE_SELF:
+ thread_group_cputime_adjusted(p, &tgutime, &tgstime);
+ utime += tgutime;
+ stime += tgstime;
+ r->ru_nvcsw += p->signal->nvcsw;
+ r->ru_nivcsw += p->signal->nivcsw;
+ r->ru_minflt += p->signal->min_flt;
+ r->ru_majflt += p->signal->maj_flt;
+ r->ru_inblock += p->signal->inblock;
+ r->ru_oublock += p->signal->oublock;
+ if (maxrss < p->signal->maxrss)
+ maxrss = p->signal->maxrss;
+ t = p;
+ do {
+ accumulate_thread_rusage(t, r);
+ } while_each_thread(p, t);
+ break;
+
+ default:
+ BUG();
}
unlock_task_sighand(p, &flags);
@@ -1585,6 +1589,7 @@ out:
if (who != RUSAGE_CHILDREN) {
struct mm_struct *mm = get_task_mm(p);
+
if (mm) {
setmax_mm_hiwater_rss(&maxrss, mm);
mmput(mm);
@@ -1596,6 +1601,7 @@ out:
int getrusage(struct task_struct *p, int who, struct rusage __user *ru)
{
struct rusage r;
+
k_getrusage(p, who, &r);
return copy_to_user(ru, &r, sizeof(r)) ? -EFAULT : 0;
}
@@ -1628,12 +1634,14 @@ SYSCALL_DEFINE1(umask, int, mask)
return mask;
}
-static int prctl_set_mm_exe_file(struct mm_struct *mm, unsigned int fd)
+static int prctl_set_mm_exe_file_locked(struct mm_struct *mm, unsigned int fd)
{
struct fd exe;
struct inode *inode;
int err;
+ VM_BUG_ON_MM(!rwsem_is_locked(&mm->mmap_sem), mm);
+
exe = fdget(fd);
if (!exe.file)
return -EBADF;
@@ -1654,8 +1662,6 @@ static int prctl_set_mm_exe_file(struct mm_struct *mm, unsigned int fd)
if (err)
goto exit;
- down_write(&mm->mmap_sem);
-
/*
* Forbid mm->exe_file change if old file still mapped.
*/
@@ -1667,7 +1673,7 @@ static int prctl_set_mm_exe_file(struct mm_struct *mm, unsigned int fd)
if (vma->vm_file &&
path_equal(&vma->vm_file->f_path,
&mm->exe_file->f_path))
- goto exit_unlock;
+ goto exit;
}
/*
@@ -1678,34 +1684,222 @@ static int prctl_set_mm_exe_file(struct mm_struct *mm, unsigned int fd)
*/
err = -EPERM;
if (test_and_set_bit(MMF_EXE_FILE_CHANGED, &mm->flags))
- goto exit_unlock;
+ goto exit;
err = 0;
set_mm_exe_file(mm, exe.file); /* this grabs a reference to exe.file */
-exit_unlock:
- up_write(&mm->mmap_sem);
-
exit:
fdput(exe);
return err;
}
+#ifdef CONFIG_CHECKPOINT_RESTORE
+/*
+ * WARNING: we don't require any capability here so be very careful
+ * in what is allowed for modification from userspace.
+ */
+static int validate_prctl_map(struct prctl_mm_map *prctl_map)
+{
+ unsigned long mmap_max_addr = TASK_SIZE;
+ struct mm_struct *mm = current->mm;
+ int error = -EINVAL, i;
+
+ static const unsigned char offsets[] = {
+ offsetof(struct prctl_mm_map, start_code),
+ offsetof(struct prctl_mm_map, end_code),
+ offsetof(struct prctl_mm_map, start_data),
+ offsetof(struct prctl_mm_map, end_data),
+ offsetof(struct prctl_mm_map, start_brk),
+ offsetof(struct prctl_mm_map, brk),
+ offsetof(struct prctl_mm_map, start_stack),
+ offsetof(struct prctl_mm_map, arg_start),
+ offsetof(struct prctl_mm_map, arg_end),
+ offsetof(struct prctl_mm_map, env_start),
+ offsetof(struct prctl_mm_map, env_end),
+ };
+
+ /*
+ * Make sure the members are not somewhere outside
+ * of allowed address space.
+ */
+ for (i = 0; i < ARRAY_SIZE(offsets); i++) {
+ u64 val = *(u64 *)((char *)prctl_map + offsets[i]);
+
+ if ((unsigned long)val >= mmap_max_addr ||
+ (unsigned long)val < mmap_min_addr)
+ goto out;
+ }
+
+ /*
+ * Make sure the pairs are ordered.
+ */
+#define __prctl_check_order(__m1, __op, __m2) \
+ ((unsigned long)prctl_map->__m1 __op \
+ (unsigned long)prctl_map->__m2) ? 0 : -EINVAL
+ error = __prctl_check_order(start_code, <, end_code);
+ error |= __prctl_check_order(start_data, <, end_data);
+ error |= __prctl_check_order(start_brk, <=, brk);
+ error |= __prctl_check_order(arg_start, <=, arg_end);
+ error |= __prctl_check_order(env_start, <=, env_end);
+ if (error)
+ goto out;
+#undef __prctl_check_order
+
+ error = -EINVAL;
+
+ /*
+ * @brk should be after @end_data in traditional maps.
+ */
+ if (prctl_map->start_brk <= prctl_map->end_data ||
+ prctl_map->brk <= prctl_map->end_data)
+ goto out;
+
+ /*
+ * Neither we should allow to override limits if they set.
+ */
+ if (check_data_rlimit(rlimit(RLIMIT_DATA), prctl_map->brk,
+ prctl_map->start_brk, prctl_map->end_data,
+ prctl_map->start_data))
+ goto out;
+
+ /*
+ * Someone is trying to cheat the auxv vector.
+ */
+ if (prctl_map->auxv_size) {
+ if (!prctl_map->auxv || prctl_map->auxv_size > sizeof(mm->saved_auxv))
+ goto out;
+ }
+
+ /*
+ * Finally, make sure the caller has the rights to
+ * change /proc/pid/exe link: only local root should
+ * be allowed to.
+ */
+ if (prctl_map->exe_fd != (u32)-1) {
+ struct user_namespace *ns = current_user_ns();
+ const struct cred *cred = current_cred();
+
+ if (!uid_eq(cred->uid, make_kuid(ns, 0)) ||
+ !gid_eq(cred->gid, make_kgid(ns, 0)))
+ goto out;
+ }
+
+ error = 0;
+out:
+ return error;
+}
+
+static int prctl_set_mm_map(int opt, const void __user *addr, unsigned long data_size)
+{
+ struct prctl_mm_map prctl_map = { .exe_fd = (u32)-1, };
+ unsigned long user_auxv[AT_VECTOR_SIZE];
+ struct mm_struct *mm = current->mm;
+ int error;
+
+ BUILD_BUG_ON(sizeof(user_auxv) != sizeof(mm->saved_auxv));
+ BUILD_BUG_ON(sizeof(struct prctl_mm_map) > 256);
+
+ if (opt == PR_SET_MM_MAP_SIZE)
+ return put_user((unsigned int)sizeof(prctl_map),
+ (unsigned int __user *)addr);
+
+ if (data_size != sizeof(prctl_map))
+ return -EINVAL;
+
+ if (copy_from_user(&prctl_map, addr, sizeof(prctl_map)))
+ return -EFAULT;
+
+ error = validate_prctl_map(&prctl_map);
+ if (error)
+ return error;
+
+ if (prctl_map.auxv_size) {
+ memset(user_auxv, 0, sizeof(user_auxv));
+ if (copy_from_user(user_auxv,
+ (const void __user *)prctl_map.auxv,
+ prctl_map.auxv_size))
+ return -EFAULT;
+
+ /* Last entry must be AT_NULL as specification requires */
+ user_auxv[AT_VECTOR_SIZE - 2] = AT_NULL;
+ user_auxv[AT_VECTOR_SIZE - 1] = AT_NULL;
+ }
+
+ down_write(&mm->mmap_sem);
+ if (prctl_map.exe_fd != (u32)-1)
+ error = prctl_set_mm_exe_file_locked(mm, prctl_map.exe_fd);
+ downgrade_write(&mm->mmap_sem);
+ if (error)
+ goto out;
+
+ /*
+ * We don't validate if these members are pointing to
+ * real present VMAs because application may have correspond
+ * VMAs already unmapped and kernel uses these members for statistics
+ * output in procfs mostly, except
+ *
+ * - @start_brk/@brk which are used in do_brk but kernel lookups
+ * for VMAs when updating these memvers so anything wrong written
+ * here cause kernel to swear at userspace program but won't lead
+ * to any problem in kernel itself
+ */
+
+ mm->start_code = prctl_map.start_code;
+ mm->end_code = prctl_map.end_code;
+ mm->start_data = prctl_map.start_data;
+ mm->end_data = prctl_map.end_data;
+ mm->start_brk = prctl_map.start_brk;
+ mm->brk = prctl_map.brk;
+ mm->start_stack = prctl_map.start_stack;
+ mm->arg_start = prctl_map.arg_start;
+ mm->arg_end = prctl_map.arg_end;
+ mm->env_start = prctl_map.env_start;
+ mm->env_end = prctl_map.env_end;
+
+ /*
+ * Note this update of @saved_auxv is lockless thus
+ * if someone reads this member in procfs while we're
+ * updating -- it may get partly updated results. It's
+ * known and acceptable trade off: we leave it as is to
+ * not introduce additional locks here making the kernel
+ * more complex.
+ */
+ if (prctl_map.auxv_size)
+ memcpy(mm->saved_auxv, user_auxv, sizeof(user_auxv));
+
+ error = 0;
+out:
+ up_read(&mm->mmap_sem);
+ return error;
+}
+#endif /* CONFIG_CHECKPOINT_RESTORE */
+
static int prctl_set_mm(int opt, unsigned long addr,
unsigned long arg4, unsigned long arg5)
{
- unsigned long rlim = rlimit(RLIMIT_DATA);
struct mm_struct *mm = current->mm;
struct vm_area_struct *vma;
int error;
- if (arg5 || (arg4 && opt != PR_SET_MM_AUXV))
+ if (arg5 || (arg4 && (opt != PR_SET_MM_AUXV &&
+ opt != PR_SET_MM_MAP &&
+ opt != PR_SET_MM_MAP_SIZE)))
return -EINVAL;
+#ifdef CONFIG_CHECKPOINT_RESTORE
+ if (opt == PR_SET_MM_MAP || opt == PR_SET_MM_MAP_SIZE)
+ return prctl_set_mm_map(opt, (const void __user *)addr, arg4);
+#endif
+
if (!capable(CAP_SYS_RESOURCE))
return -EPERM;
- if (opt == PR_SET_MM_EXE_FILE)
- return prctl_set_mm_exe_file(mm, (unsigned int)addr);
+ if (opt == PR_SET_MM_EXE_FILE) {
+ down_write(&mm->mmap_sem);
+ error = prctl_set_mm_exe_file_locked(mm, (unsigned int)addr);
+ up_write(&mm->mmap_sem);
+ return error;
+ }
if (addr >= TASK_SIZE || addr < mmap_min_addr)
return -EINVAL;
@@ -1733,9 +1927,8 @@ static int prctl_set_mm(int opt, unsigned long addr,
if (addr <= mm->end_data)
goto out;
- if (rlim < RLIM_INFINITY &&
- (mm->brk - addr) +
- (mm->end_data - mm->start_data) > rlim)
+ if (check_data_rlimit(rlimit(RLIMIT_DATA), mm->brk, addr,
+ mm->end_data, mm->start_data))
goto out;
mm->start_brk = addr;
@@ -1745,9 +1938,8 @@ static int prctl_set_mm(int opt, unsigned long addr,
if (addr <= mm->end_data)
goto out;
- if (rlim < RLIM_INFINITY &&
- (addr - mm->start_brk) +
- (mm->end_data - mm->start_data) > rlim)
+ if (check_data_rlimit(rlimit(RLIMIT_DATA), addr, mm->start_brk,
+ mm->end_data, mm->start_data))
goto out;
mm->brk = addr;
@@ -2023,6 +2215,7 @@ SYSCALL_DEFINE3(getcpu, unsigned __user *, cpup, unsigned __user *, nodep,
{
int err = 0;
int cpu = raw_smp_processor_id();
+
if (cpup)
err |= put_user(cpu, cpup);
if (nodep)
@@ -2135,7 +2328,7 @@ COMPAT_SYSCALL_DEFINE1(sysinfo, struct compat_sysinfo __user *, info)
/* Check to see if any memory value is too large for 32-bit and scale
* down if needed
*/
- if ((s.totalram >> 32) || (s.totalswap >> 32)) {
+ if (upper_32_bits(s.totalram) || upper_32_bits(s.totalswap)) {
int bitcount = 0;
while (s.mem_unit < PAGE_SIZE) {
diff --git a/kernel/sys_ni.c b/kernel/sys_ni.c
index 391d4ddb6f4b..02aa4185b17e 100644
--- a/kernel/sys_ni.c
+++ b/kernel/sys_ni.c
@@ -156,6 +156,9 @@ cond_syscall(sys_process_vm_writev);
cond_syscall(compat_sys_process_vm_readv);
cond_syscall(compat_sys_process_vm_writev);
cond_syscall(sys_uselib);
+cond_syscall(sys_fadvise64);
+cond_syscall(sys_fadvise64_64);
+cond_syscall(sys_madvise);
/* arch-specific weak syscall entries */
cond_syscall(sys_pciconfig_read);
@@ -218,3 +221,6 @@ cond_syscall(sys_kcmp);
/* operate on Secure Computing state */
cond_syscall(sys_seccomp);
+
+/* access BPF programs and maps */
+cond_syscall(sys_bpf);
diff --git a/kernel/sysctl.c b/kernel/sysctl.c
index 75875a741b5e..4aada6d9fe74 100644
--- a/kernel/sysctl.c
+++ b/kernel/sysctl.c
@@ -1055,15 +1055,6 @@ static struct ctl_table kern_table[] = {
.child = key_sysctls,
},
#endif
-#ifdef CONFIG_RCU_TORTURE_TEST
- {
- .procname = "rcutorture_runnable",
- .data = &rcutorture_runnable,
- .maxlen = sizeof(int),
- .mode = 0644,
- .proc_handler = proc_dointvec,
- },
-#endif
#ifdef CONFIG_PERF_EVENTS
/*
* User-space scripts rely on the existence of this file
@@ -1460,13 +1451,6 @@ static struct ctl_table vm_table[] = {
.extra2 = &one,
},
#endif
- {
- .procname = "scan_unevictable_pages",
- .data = &scan_unevictable_pages,
- .maxlen = sizeof(scan_unevictable_pages),
- .mode = 0644,
- .proc_handler = scan_unevictable_handler,
- },
#ifdef CONFIG_MEMORY_FAILURE
{
.procname = "memory_failure_early_kill",
diff --git a/kernel/sysctl_binary.c b/kernel/sysctl_binary.c
index e4ba9a5a5ccb..9a4f750a2963 100644
--- a/kernel/sysctl_binary.c
+++ b/kernel/sysctl_binary.c
@@ -390,7 +390,6 @@ static const struct bin_table bin_net_ipv4_table[] = {
{ CTL_INT, NET_TCP_MTU_PROBING, "tcp_mtu_probing" },
{ CTL_INT, NET_TCP_BASE_MSS, "tcp_base_mss" },
{ CTL_INT, NET_IPV4_TCP_WORKAROUND_SIGNED_WINDOWS, "tcp_workaround_signed_windows" },
- { CTL_INT, NET_TCP_DMA_COPYBREAK, "tcp_dma_copybreak" },
{ CTL_INT, NET_TCP_SLOW_START_AFTER_IDLE, "tcp_slow_start_after_idle" },
{ CTL_INT, NET_CIPSOV4_CACHE_ENABLE, "cipso_cache_enable" },
{ CTL_INT, NET_CIPSOV4_CACHE_BUCKET_SIZE, "cipso_cache_bucket_size" },
diff --git a/kernel/time/alarmtimer.c b/kernel/time/alarmtimer.c
index 4aec4a457431..a7077d3ae52f 100644
--- a/kernel/time/alarmtimer.c
+++ b/kernel/time/alarmtimer.c
@@ -464,18 +464,26 @@ static enum alarmtimer_type clock2alarm(clockid_t clockid)
static enum alarmtimer_restart alarm_handle_timer(struct alarm *alarm,
ktime_t now)
{
+ unsigned long flags;
struct k_itimer *ptr = container_of(alarm, struct k_itimer,
it.alarm.alarmtimer);
- if (posix_timer_event(ptr, 0) != 0)
- ptr->it_overrun++;
+ enum alarmtimer_restart result = ALARMTIMER_NORESTART;
+
+ spin_lock_irqsave(&ptr->it_lock, flags);
+ if ((ptr->it_sigev_notify & ~SIGEV_THREAD_ID) != SIGEV_NONE) {
+ if (posix_timer_event(ptr, 0) != 0)
+ ptr->it_overrun++;
+ }
/* Re-add periodic timers */
if (ptr->it.alarm.interval.tv64) {
ptr->it_overrun += alarm_forward(alarm, now,
ptr->it.alarm.interval);
- return ALARMTIMER_RESTART;
+ result = ALARMTIMER_RESTART;
}
- return ALARMTIMER_NORESTART;
+ spin_unlock_irqrestore(&ptr->it_lock, flags);
+
+ return result;
}
/**
@@ -541,18 +549,22 @@ static int alarm_timer_create(struct k_itimer *new_timer)
* @new_timer: k_itimer pointer
* @cur_setting: itimerspec data to fill
*
- * Copies the itimerspec data out from the k_itimer
+ * Copies out the current itimerspec data
*/
static void alarm_timer_get(struct k_itimer *timr,
struct itimerspec *cur_setting)
{
- memset(cur_setting, 0, sizeof(struct itimerspec));
+ ktime_t relative_expiry_time =
+ alarm_expires_remaining(&(timr->it.alarm.alarmtimer));
+
+ if (ktime_to_ns(relative_expiry_time) > 0) {
+ cur_setting->it_value = ktime_to_timespec(relative_expiry_time);
+ } else {
+ cur_setting->it_value.tv_sec = 0;
+ cur_setting->it_value.tv_nsec = 0;
+ }
- cur_setting->it_interval =
- ktime_to_timespec(timr->it.alarm.interval);
- cur_setting->it_value =
- ktime_to_timespec(timr->it.alarm.alarmtimer.node.expires);
- return;
+ cur_setting->it_interval = ktime_to_timespec(timr->it.alarm.interval);
}
/**
diff --git a/kernel/time/hrtimer.c b/kernel/time/hrtimer.c
index a50600d87fb7..37e50aadd471 100644
--- a/kernel/time/hrtimer.c
+++ b/kernel/time/hrtimer.c
@@ -1776,7 +1776,6 @@ schedule_hrtimeout_range_clock(ktime_t *expires, unsigned long delta,
*/
if (!expires) {
schedule();
- __set_current_state(TASK_RUNNING);
return -EINTR;
}
diff --git a/kernel/time/posix-cpu-timers.c b/kernel/time/posix-cpu-timers.c
index 3b8946416a5f..492b986195d5 100644
--- a/kernel/time/posix-cpu-timers.c
+++ b/kernel/time/posix-cpu-timers.c
@@ -272,22 +272,8 @@ static int posix_cpu_clock_get_task(struct task_struct *tsk,
if (same_thread_group(tsk, current))
err = cpu_clock_sample(which_clock, tsk, &rtn);
} else {
- unsigned long flags;
- struct sighand_struct *sighand;
-
- /*
- * while_each_thread() is not yet entirely RCU safe,
- * keep locking the group while sampling process
- * clock for now.
- */
- sighand = lock_task_sighand(tsk, &flags);
- if (!sighand)
- return err;
-
if (tsk == current || thread_group_leader(tsk))
err = cpu_clock_sample_group(which_clock, tsk, &rtn);
-
- unlock_task_sighand(tsk, &flags);
}
if (!err)
diff --git a/kernel/time/tick-common.c b/kernel/time/tick-common.c
index decfb5f6edb0..7efeedf53ebd 100644
--- a/kernel/time/tick-common.c
+++ b/kernel/time/tick-common.c
@@ -400,4 +400,5 @@ void tick_resume(void)
void __init tick_init(void)
{
tick_broadcast_init();
+ tick_nohz_init();
}
diff --git a/kernel/time/tick-internal.h b/kernel/time/tick-internal.h
index c19c1d84b6f3..366aeb4f2c66 100644
--- a/kernel/time/tick-internal.h
+++ b/kernel/time/tick-internal.h
@@ -99,6 +99,13 @@ static inline int tick_broadcast_oneshot_active(void) { return 0; }
static inline bool tick_broadcast_oneshot_available(void) { return false; }
#endif /* !TICK_ONESHOT */
+/* NO_HZ_FULL internal */
+#ifdef CONFIG_NO_HZ_FULL
+extern void tick_nohz_init(void);
+# else
+static inline void tick_nohz_init(void) { }
+#endif
+
/*
* Broadcasting support
*/
diff --git a/kernel/time/tick-sched.c b/kernel/time/tick-sched.c
index 3cadc112519f..7b5741fc4110 100644
--- a/kernel/time/tick-sched.c
+++ b/kernel/time/tick-sched.c
@@ -225,6 +225,20 @@ static DEFINE_PER_CPU(struct irq_work, nohz_full_kick_work) = {
};
/*
+ * Kick this CPU if it's full dynticks in order to force it to
+ * re-evaluate its dependency on the tick and restart it if necessary.
+ * This kick, unlike tick_nohz_full_kick_cpu() and tick_nohz_full_kick_all(),
+ * is NMI safe.
+ */
+void tick_nohz_full_kick(void)
+{
+ if (!tick_nohz_full_cpu(smp_processor_id()))
+ return;
+
+ irq_work_queue(&__get_cpu_var(nohz_full_kick_work));
+}
+
+/*
* Kick the CPU if it's full dynticks in order to force it to
* re-evaluate its dependency on the tick and restart it if necessary.
*/
@@ -281,22 +295,12 @@ out:
/* Parse the boot-time nohz CPU list from the kernel parameters. */
static int __init tick_nohz_full_setup(char *str)
{
- int cpu;
-
alloc_bootmem_cpumask_var(&tick_nohz_full_mask);
- alloc_bootmem_cpumask_var(&housekeeping_mask);
if (cpulist_parse(str, tick_nohz_full_mask) < 0) {
pr_warning("NOHZ: Incorrect nohz_full cpumask\n");
+ free_bootmem_cpumask_var(tick_nohz_full_mask);
return 1;
}
-
- cpu = smp_processor_id();
- if (cpumask_test_cpu(cpu, tick_nohz_full_mask)) {
- pr_warning("NO_HZ: Clearing %d from nohz_full range for timekeeping\n", cpu);
- cpumask_clear_cpu(cpu, tick_nohz_full_mask);
- }
- cpumask_andnot(housekeeping_mask,
- cpu_possible_mask, tick_nohz_full_mask);
tick_nohz_full_running = true;
return 1;
@@ -335,18 +339,11 @@ static int tick_nohz_init_all(void)
#ifdef CONFIG_NO_HZ_FULL_ALL
if (!alloc_cpumask_var(&tick_nohz_full_mask, GFP_KERNEL)) {
- pr_err("NO_HZ: Can't allocate full dynticks cpumask\n");
- return err;
- }
- if (!alloc_cpumask_var(&housekeeping_mask, GFP_KERNEL)) {
- pr_err("NO_HZ: Can't allocate not-full dynticks cpumask\n");
+ WARN(1, "NO_HZ: Can't allocate full dynticks cpumask\n");
return err;
}
err = 0;
cpumask_setall(tick_nohz_full_mask);
- cpumask_clear_cpu(smp_processor_id(), tick_nohz_full_mask);
- cpumask_clear(housekeeping_mask);
- cpumask_set_cpu(smp_processor_id(), housekeeping_mask);
tick_nohz_full_running = true;
#endif
return err;
@@ -361,6 +358,37 @@ void __init tick_nohz_init(void)
return;
}
+ if (!alloc_cpumask_var(&housekeeping_mask, GFP_KERNEL)) {
+ WARN(1, "NO_HZ: Can't allocate not-full dynticks cpumask\n");
+ cpumask_clear(tick_nohz_full_mask);
+ tick_nohz_full_running = false;
+ return;
+ }
+
+ /*
+ * Full dynticks uses irq work to drive the tick rescheduling on safe
+ * locking contexts. But then we need irq work to raise its own
+ * interrupts to avoid circular dependency on the tick
+ */
+ if (!arch_irq_work_has_interrupt()) {
+ pr_warning("NO_HZ: Can't run full dynticks because arch doesn't "
+ "support irq work self-IPIs\n");
+ cpumask_clear(tick_nohz_full_mask);
+ cpumask_copy(housekeeping_mask, cpu_possible_mask);
+ tick_nohz_full_running = false;
+ return;
+ }
+
+ cpu = smp_processor_id();
+
+ if (cpumask_test_cpu(cpu, tick_nohz_full_mask)) {
+ pr_warning("NO_HZ: Clearing %d from nohz_full range for timekeeping\n", cpu);
+ cpumask_clear_cpu(cpu, tick_nohz_full_mask);
+ }
+
+ cpumask_andnot(housekeeping_mask,
+ cpu_possible_mask, tick_nohz_full_mask);
+
for_each_cpu(cpu, tick_nohz_full_mask)
context_tracking_cpu_set(cpu);
@@ -558,7 +586,7 @@ static ktime_t tick_nohz_stop_sched_tick(struct tick_sched *ts,
} while (read_seqretry(&jiffies_lock, seq));
if (rcu_needs_cpu(cpu, &rcu_delta_jiffies) ||
- arch_needs_cpu(cpu) || irq_work_needs_cpu()) {
+ arch_needs_cpu() || irq_work_needs_cpu()) {
next_jiffies = last_jiffies + 1;
delta_jiffies = 1;
} else {
@@ -968,6 +996,10 @@ static void tick_nohz_handler(struct clock_event_device *dev)
tick_sched_do_timer(now);
tick_sched_handle(ts, regs);
+ /* No need to reprogram if we are running tickless */
+ if (unlikely(ts->tick_stopped))
+ return;
+
while (tick_nohz_reprogram(ts, now)) {
now = ktime_get();
tick_do_update_jiffies64(now);
@@ -1095,6 +1127,10 @@ static enum hrtimer_restart tick_sched_timer(struct hrtimer *timer)
if (regs)
tick_sched_handle(ts, regs);
+ /* No need to reprogram if we are in idle or full dynticks mode */
+ if (unlikely(ts->tick_stopped))
+ return HRTIMER_NORESTART;
+
hrtimer_forward(timer, now, tick_period);
return HRTIMER_RESTART;
diff --git a/kernel/time/time.c b/kernel/time/time.c
index f0294ba14634..a9ae20fb0b11 100644
--- a/kernel/time/time.c
+++ b/kernel/time/time.c
@@ -559,17 +559,20 @@ EXPORT_SYMBOL(usecs_to_jiffies);
* that a remainder subtract here would not do the right thing as the
* resolution values don't fall on second boundries. I.e. the line:
* nsec -= nsec % TICK_NSEC; is NOT a correct resolution rounding.
+ * Note that due to the small error in the multiplier here, this
+ * rounding is incorrect for sufficiently large values of tv_nsec, but
+ * well formed timespecs should have tv_nsec < NSEC_PER_SEC, so we're
+ * OK.
*
* Rather, we just shift the bits off the right.
*
* The >> (NSEC_JIFFIE_SC - SEC_JIFFIE_SC) converts the scaled nsec
* value to a scaled second value.
*/
-unsigned long
-timespec_to_jiffies(const struct timespec *value)
+static unsigned long
+__timespec_to_jiffies(unsigned long sec, long nsec)
{
- unsigned long sec = value->tv_sec;
- long nsec = value->tv_nsec + TICK_NSEC - 1;
+ nsec = nsec + TICK_NSEC - 1;
if (sec >= MAX_SEC_IN_JIFFIES){
sec = MAX_SEC_IN_JIFFIES;
@@ -580,6 +583,13 @@ timespec_to_jiffies(const struct timespec *value)
(NSEC_JIFFIE_SC - SEC_JIFFIE_SC))) >> SEC_JIFFIE_SC;
}
+
+unsigned long
+timespec_to_jiffies(const struct timespec *value)
+{
+ return __timespec_to_jiffies(value->tv_sec, value->tv_nsec);
+}
+
EXPORT_SYMBOL(timespec_to_jiffies);
void
@@ -596,31 +606,27 @@ jiffies_to_timespec(const unsigned long jiffies, struct timespec *value)
}
EXPORT_SYMBOL(jiffies_to_timespec);
-/* Same for "timeval"
- *
- * Well, almost. The problem here is that the real system resolution is
- * in nanoseconds and the value being converted is in micro seconds.
- * Also for some machines (those that use HZ = 1024, in-particular),
- * there is a LARGE error in the tick size in microseconds.
-
- * The solution we use is to do the rounding AFTER we convert the
- * microsecond part. Thus the USEC_ROUND, the bits to be shifted off.
- * Instruction wise, this should cost only an additional add with carry
- * instruction above the way it was done above.
+/*
+ * We could use a similar algorithm to timespec_to_jiffies (with a
+ * different multiplier for usec instead of nsec). But this has a
+ * problem with rounding: we can't exactly add TICK_NSEC - 1 to the
+ * usec value, since it's not necessarily integral.
+ *
+ * We could instead round in the intermediate scaled representation
+ * (i.e. in units of 1/2^(large scale) jiffies) but that's also
+ * perilous: the scaling introduces a small positive error, which
+ * combined with a division-rounding-upward (i.e. adding 2^(scale) - 1
+ * units to the intermediate before shifting) leads to accidental
+ * overflow and overestimates.
+ *
+ * At the cost of one additional multiplication by a constant, just
+ * use the timespec implementation.
*/
unsigned long
timeval_to_jiffies(const struct timeval *value)
{
- unsigned long sec = value->tv_sec;
- long usec = value->tv_usec;
-
- if (sec >= MAX_SEC_IN_JIFFIES){
- sec = MAX_SEC_IN_JIFFIES;
- usec = 0;
- }
- return (((u64)sec * SEC_CONVERSION) +
- (((u64)usec * USEC_CONVERSION + USEC_ROUND) >>
- (USEC_JIFFIE_SC - SEC_JIFFIE_SC))) >> SEC_JIFFIE_SC;
+ return __timespec_to_jiffies(value->tv_sec,
+ value->tv_usec * NSEC_PER_USEC);
}
EXPORT_SYMBOL(timeval_to_jiffies);
diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c
index fb4a9c2cf8d9..ec1791fae965 100644
--- a/kernel/time/timekeeping.c
+++ b/kernel/time/timekeeping.c
@@ -442,11 +442,12 @@ static void timekeeping_update(struct timekeeper *tk, unsigned int action)
tk->ntp_error = 0;
ntp_clear();
}
- update_vsyscall(tk);
- update_pvclock_gtod(tk, action & TK_CLOCK_WAS_SET);
tk_update_ktime_data(tk);
+ update_vsyscall(tk);
+ update_pvclock_gtod(tk, action & TK_CLOCK_WAS_SET);
+
if (action & TK_MIRROR)
memcpy(&shadow_timekeeper, &tk_core.timekeeper,
sizeof(tk_core.timekeeper));
diff --git a/kernel/time/timer.c b/kernel/time/timer.c
index 04d8ed8399b0..3260ffdb368f 100644
--- a/kernel/time/timer.c
+++ b/kernel/time/timer.c
@@ -1385,7 +1385,7 @@ void update_process_times(int user_tick)
rcu_check_callbacks(cpu, user_tick);
#ifdef CONFIG_IRQ_WORK
if (in_irq())
- irq_work_run();
+ irq_work_tick();
#endif
scheduler_tick();
run_posix_cpu_timers(p);
diff --git a/kernel/torture.c b/kernel/torture.c
index d600af21f022..dd70993c266c 100644
--- a/kernel/torture.c
+++ b/kernel/torture.c
@@ -211,18 +211,16 @@ EXPORT_SYMBOL_GPL(torture_onoff_cleanup);
/*
* Print online/offline testing statistics.
*/
-char *torture_onoff_stats(char *page)
+void torture_onoff_stats(void)
{
#ifdef CONFIG_HOTPLUG_CPU
- page += sprintf(page,
- "onoff: %ld/%ld:%ld/%ld %d,%d:%d,%d %lu:%lu (HZ=%d) ",
- n_online_successes, n_online_attempts,
- n_offline_successes, n_offline_attempts,
- min_online, max_online,
- min_offline, max_offline,
- sum_online, sum_offline, HZ);
+ pr_cont("onoff: %ld/%ld:%ld/%ld %d,%d:%d,%d %lu:%lu (HZ=%d) ",
+ n_online_successes, n_online_attempts,
+ n_offline_successes, n_offline_attempts,
+ min_online, max_online,
+ min_offline, max_offline,
+ sum_online, sum_offline, HZ);
#endif /* #ifdef CONFIG_HOTPLUG_CPU */
- return page;
}
EXPORT_SYMBOL_GPL(torture_onoff_stats);
@@ -635,8 +633,13 @@ EXPORT_SYMBOL_GPL(torture_init_end);
*
* This must be called before the caller starts shutting down its own
* kthreads.
+ *
+ * Both torture_cleanup_begin() and torture_cleanup_end() must be paired,
+ * in order to correctly perform the cleanup. They are separated because
+ * threads can still need to reference the torture_type type, thus nullify
+ * only after completing all other relevant calls.
*/
-bool torture_cleanup(void)
+bool torture_cleanup_begin(void)
{
mutex_lock(&fullstop_mutex);
if (ACCESS_ONCE(fullstop) == FULLSTOP_SHUTDOWN) {
@@ -651,12 +654,17 @@ bool torture_cleanup(void)
torture_shuffle_cleanup();
torture_stutter_cleanup();
torture_onoff_cleanup();
+ return false;
+}
+EXPORT_SYMBOL_GPL(torture_cleanup_begin);
+
+void torture_cleanup_end(void)
+{
mutex_lock(&fullstop_mutex);
torture_type = NULL;
mutex_unlock(&fullstop_mutex);
- return false;
}
-EXPORT_SYMBOL_GPL(torture_cleanup);
+EXPORT_SYMBOL_GPL(torture_cleanup_end);
/*
* Is it time for the current torture test to stop?
diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index 1654b12c891a..fb186b9ddf51 100644
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -65,15 +65,21 @@
#define FL_GLOBAL_CONTROL_MASK (FTRACE_OPS_FL_CONTROL)
#ifdef CONFIG_DYNAMIC_FTRACE
-#define INIT_REGEX_LOCK(opsname) \
- .regex_lock = __MUTEX_INITIALIZER(opsname.regex_lock),
+#define INIT_OPS_HASH(opsname) \
+ .func_hash = &opsname.local_hash, \
+ .local_hash.regex_lock = __MUTEX_INITIALIZER(opsname.local_hash.regex_lock),
+#define ASSIGN_OPS_HASH(opsname, val) \
+ .func_hash = val, \
+ .local_hash.regex_lock = __MUTEX_INITIALIZER(opsname.local_hash.regex_lock),
#else
-#define INIT_REGEX_LOCK(opsname)
+#define INIT_OPS_HASH(opsname)
+#define ASSIGN_OPS_HASH(opsname, val)
#endif
static struct ftrace_ops ftrace_list_end __read_mostly = {
.func = ftrace_stub,
.flags = FTRACE_OPS_FL_RECURSION_SAFE | FTRACE_OPS_FL_STUB,
+ INIT_OPS_HASH(ftrace_list_end)
};
/* ftrace_enabled is a method to turn ftrace on or off */
@@ -107,6 +113,9 @@ ftrace_func_t ftrace_pid_function __read_mostly = ftrace_stub;
static struct ftrace_ops global_ops;
static struct ftrace_ops control_ops;
+static void ftrace_ops_recurs_func(unsigned long ip, unsigned long parent_ip,
+ struct ftrace_ops *op, struct pt_regs *regs);
+
#if ARCH_SUPPORTS_FTRACE_OPS
static void ftrace_ops_list_func(unsigned long ip, unsigned long parent_ip,
struct ftrace_ops *op, struct pt_regs *regs);
@@ -140,7 +149,8 @@ static inline void ftrace_ops_init(struct ftrace_ops *ops)
{
#ifdef CONFIG_DYNAMIC_FTRACE
if (!(ops->flags & FTRACE_OPS_FL_INITIALIZED)) {
- mutex_init(&ops->regex_lock);
+ mutex_init(&ops->local_hash.regex_lock);
+ ops->func_hash = &ops->local_hash;
ops->flags |= FTRACE_OPS_FL_INITIALIZED;
}
#endif
@@ -244,18 +254,24 @@ static void update_ftrace_function(void)
ftrace_func_t func;
/*
+ * Prepare the ftrace_ops that the arch callback will use.
+ * If there's only one ftrace_ops registered, the ftrace_ops_list
+ * will point to the ops we want.
+ */
+ set_function_trace_op = ftrace_ops_list;
+
+ /* If there's no ftrace_ops registered, just call the stub function */
+ if (ftrace_ops_list == &ftrace_list_end) {
+ func = ftrace_stub;
+
+ /*
* If we are at the end of the list and this ops is
* recursion safe and not dynamic and the arch supports passing ops,
* then have the mcount trampoline call the function directly.
*/
- if (ftrace_ops_list == &ftrace_list_end ||
- (ftrace_ops_list->next == &ftrace_list_end &&
- !(ftrace_ops_list->flags & FTRACE_OPS_FL_DYNAMIC) &&
- (ftrace_ops_list->flags & FTRACE_OPS_FL_RECURSION_SAFE) &&
- !FTRACE_FORCE_LIST_FUNC)) {
- /* Set the ftrace_ops that the arch callback uses */
- set_function_trace_op = ftrace_ops_list;
- func = ftrace_ops_list->func;
+ } else if (ftrace_ops_list->next == &ftrace_list_end) {
+ func = ftrace_ops_get_func(ftrace_ops_list);
+
} else {
/* Just use the default ftrace_ops */
set_function_trace_op = &ftrace_list_end;
@@ -899,7 +915,7 @@ static void unregister_ftrace_profiler(void)
static struct ftrace_ops ftrace_profile_ops __read_mostly = {
.func = function_profile_call,
.flags = FTRACE_OPS_FL_RECURSION_SAFE | FTRACE_OPS_FL_INITIALIZED,
- INIT_REGEX_LOCK(ftrace_profile_ops)
+ INIT_OPS_HASH(ftrace_profile_ops)
};
static int register_ftrace_profiler(void)
@@ -1041,6 +1057,12 @@ static struct pid * const ftrace_swapper_pid = &init_struct_pid;
static struct ftrace_ops *removed_ops;
+/*
+ * Set when doing a global update, like enabling all recs or disabling them.
+ * It is not set when just updating a single ftrace_ops.
+ */
+static bool update_all_ops;
+
#ifndef CONFIG_FTRACE_MCOUNT_RECORD
# error Dynamic ftrace depends on MCOUNT_RECORD
#endif
@@ -1081,11 +1103,12 @@ static const struct ftrace_hash empty_hash = {
#define EMPTY_HASH ((struct ftrace_hash *)&empty_hash)
static struct ftrace_ops global_ops = {
- .func = ftrace_stub,
- .notrace_hash = EMPTY_HASH,
- .filter_hash = EMPTY_HASH,
- .flags = FTRACE_OPS_FL_RECURSION_SAFE | FTRACE_OPS_FL_INITIALIZED,
- INIT_REGEX_LOCK(global_ops)
+ .func = ftrace_stub,
+ .local_hash.notrace_hash = EMPTY_HASH,
+ .local_hash.filter_hash = EMPTY_HASH,
+ INIT_OPS_HASH(global_ops)
+ .flags = FTRACE_OPS_FL_RECURSION_SAFE |
+ FTRACE_OPS_FL_INITIALIZED,
};
struct ftrace_page {
@@ -1226,8 +1249,8 @@ static void free_ftrace_hash_rcu(struct ftrace_hash *hash)
void ftrace_free_filter(struct ftrace_ops *ops)
{
ftrace_ops_init(ops);
- free_ftrace_hash(ops->filter_hash);
- free_ftrace_hash(ops->notrace_hash);
+ free_ftrace_hash(ops->func_hash->filter_hash);
+ free_ftrace_hash(ops->func_hash->notrace_hash);
}
static struct ftrace_hash *alloc_ftrace_hash(int size_bits)
@@ -1288,9 +1311,9 @@ alloc_and_copy_ftrace_hash(int size_bits, struct ftrace_hash *hash)
}
static void
-ftrace_hash_rec_disable(struct ftrace_ops *ops, int filter_hash);
+ftrace_hash_rec_disable_modify(struct ftrace_ops *ops, int filter_hash);
static void
-ftrace_hash_rec_enable(struct ftrace_ops *ops, int filter_hash);
+ftrace_hash_rec_enable_modify(struct ftrace_ops *ops, int filter_hash);
static int
ftrace_hash_move(struct ftrace_ops *ops, int enable,
@@ -1299,7 +1322,6 @@ ftrace_hash_move(struct ftrace_ops *ops, int enable,
struct ftrace_func_entry *entry;
struct hlist_node *tn;
struct hlist_head *hhd;
- struct ftrace_hash *old_hash;
struct ftrace_hash *new_hash;
int size = src->count;
int bits = 0;
@@ -1342,17 +1364,30 @@ update:
* Remove the current set, update the hash and add
* them back.
*/
- ftrace_hash_rec_disable(ops, enable);
+ ftrace_hash_rec_disable_modify(ops, enable);
- old_hash = *dst;
rcu_assign_pointer(*dst, new_hash);
- free_ftrace_hash_rcu(old_hash);
- ftrace_hash_rec_enable(ops, enable);
+ ftrace_hash_rec_enable_modify(ops, enable);
return 0;
}
+static bool hash_contains_ip(unsigned long ip,
+ struct ftrace_ops_hash *hash)
+{
+ /*
+ * The function record is a match if it exists in the filter
+ * hash and not in the notrace hash. Note, an emty hash is
+ * considered a match for the filter hash, but an empty
+ * notrace hash is considered not in the notrace hash.
+ */
+ return (ftrace_hash_empty(hash->filter_hash) ||
+ ftrace_lookup_ip(hash->filter_hash, ip)) &&
+ (ftrace_hash_empty(hash->notrace_hash) ||
+ !ftrace_lookup_ip(hash->notrace_hash, ip));
+}
+
/*
* Test the hashes for this ops to see if we want to call
* the ops->func or not.
@@ -1368,8 +1403,7 @@ update:
static int
ftrace_ops_test(struct ftrace_ops *ops, unsigned long ip, void *regs)
{
- struct ftrace_hash *filter_hash;
- struct ftrace_hash *notrace_hash;
+ struct ftrace_ops_hash hash;
int ret;
#ifdef CONFIG_DYNAMIC_FTRACE_WITH_REGS
@@ -1382,13 +1416,10 @@ ftrace_ops_test(struct ftrace_ops *ops, unsigned long ip, void *regs)
return 0;
#endif
- filter_hash = rcu_dereference_raw_notrace(ops->filter_hash);
- notrace_hash = rcu_dereference_raw_notrace(ops->notrace_hash);
+ hash.filter_hash = rcu_dereference_raw_notrace(ops->func_hash->filter_hash);
+ hash.notrace_hash = rcu_dereference_raw_notrace(ops->func_hash->notrace_hash);
- if ((ftrace_hash_empty(filter_hash) ||
- ftrace_lookup_ip(filter_hash, ip)) &&
- (ftrace_hash_empty(notrace_hash) ||
- !ftrace_lookup_ip(notrace_hash, ip)))
+ if (hash_contains_ip(ip, &hash))
ret = 1;
else
ret = 0;
@@ -1500,33 +1531,6 @@ static bool test_rec_ops_needs_regs(struct dyn_ftrace *rec)
return keep_regs;
}
-static void ftrace_remove_tramp(struct ftrace_ops *ops,
- struct dyn_ftrace *rec)
-{
- struct ftrace_func_entry *entry;
-
- entry = ftrace_lookup_ip(ops->tramp_hash, rec->ip);
- if (!entry)
- return;
-
- /*
- * The tramp_hash entry will be removed at time
- * of update.
- */
- ops->nr_trampolines--;
- rec->flags &= ~FTRACE_FL_TRAMP;
-}
-
-static void ftrace_clear_tramps(struct dyn_ftrace *rec)
-{
- struct ftrace_ops *op;
-
- do_for_each_ftrace_op(op, ftrace_ops_list) {
- if (op->nr_trampolines)
- ftrace_remove_tramp(op, rec);
- } while_for_each_ftrace_op(op);
-}
-
static void __ftrace_hash_rec_update(struct ftrace_ops *ops,
int filter_hash,
bool inc)
@@ -1554,14 +1558,14 @@ static void __ftrace_hash_rec_update(struct ftrace_ops *ops,
* gets inversed.
*/
if (filter_hash) {
- hash = ops->filter_hash;
- other_hash = ops->notrace_hash;
+ hash = ops->func_hash->filter_hash;
+ other_hash = ops->func_hash->notrace_hash;
if (ftrace_hash_empty(hash))
all = 1;
} else {
inc = !inc;
- hash = ops->notrace_hash;
- other_hash = ops->filter_hash;
+ hash = ops->func_hash->notrace_hash;
+ other_hash = ops->func_hash->filter_hash;
/*
* If the notrace hash has no items,
* then there's nothing to do.
@@ -1615,22 +1619,17 @@ static void __ftrace_hash_rec_update(struct ftrace_ops *ops,
* function, and the ops has a trampoline registered
* for it, then we can call it directly.
*/
- if (ftrace_rec_count(rec) == 1 && ops->trampoline) {
+ if (ftrace_rec_count(rec) == 1 && ops->trampoline)
rec->flags |= FTRACE_FL_TRAMP;
- ops->nr_trampolines++;
- } else {
+ else
/*
* If we are adding another function callback
* to this function, and the previous had a
- * trampoline used, then we need to go back to
- * the default trampoline.
+ * custom trampoline in use, then we need to go
+ * back to the default trampoline.
*/
rec->flags &= ~FTRACE_FL_TRAMP;
- /* remove trampolines from any ops for this rec */
- ftrace_clear_tramps(rec);
- }
-
/*
* If any ops wants regs saved for this function
* then all ops will get saved regs.
@@ -1642,9 +1641,6 @@ static void __ftrace_hash_rec_update(struct ftrace_ops *ops,
return;
rec->flags--;
- if (ops->trampoline && !ftrace_rec_count(rec))
- ftrace_remove_tramp(ops, rec);
-
/*
* If the rec had REGS enabled and the ops that is
* being removed had REGS set, then see if there is
@@ -1659,6 +1655,17 @@ static void __ftrace_hash_rec_update(struct ftrace_ops *ops,
}
/*
+ * If the rec had TRAMP enabled, then it needs to
+ * be cleared. As TRAMP can only be enabled iff
+ * there is only a single ops attached to it.
+ * In otherwords, always disable it on decrementing.
+ * In the future, we may set it if rec count is
+ * decremented to one, and the ops that is left
+ * has a trampoline.
+ */
+ rec->flags &= ~FTRACE_FL_TRAMP;
+
+ /*
* flags will be cleared in ftrace_check_record()
* if rec count is zero.
*/
@@ -1682,6 +1689,41 @@ static void ftrace_hash_rec_enable(struct ftrace_ops *ops,
__ftrace_hash_rec_update(ops, filter_hash, 1);
}
+static void ftrace_hash_rec_update_modify(struct ftrace_ops *ops,
+ int filter_hash, int inc)
+{
+ struct ftrace_ops *op;
+
+ __ftrace_hash_rec_update(ops, filter_hash, inc);
+
+ if (ops->func_hash != &global_ops.local_hash)
+ return;
+
+ /*
+ * If the ops shares the global_ops hash, then we need to update
+ * all ops that are enabled and use this hash.
+ */
+ do_for_each_ftrace_op(op, ftrace_ops_list) {
+ /* Already done */
+ if (op == ops)
+ continue;
+ if (op->func_hash == &global_ops.local_hash)
+ __ftrace_hash_rec_update(op, filter_hash, inc);
+ } while_for_each_ftrace_op(op);
+}
+
+static void ftrace_hash_rec_disable_modify(struct ftrace_ops *ops,
+ int filter_hash)
+{
+ ftrace_hash_rec_update_modify(ops, filter_hash, 0);
+}
+
+static void ftrace_hash_rec_enable_modify(struct ftrace_ops *ops,
+ int filter_hash)
+{
+ ftrace_hash_rec_update_modify(ops, filter_hash, 1);
+}
+
static void print_ip_ins(const char *fmt, unsigned char *p)
{
int i;
@@ -1842,21 +1884,72 @@ int ftrace_test_record(struct dyn_ftrace *rec, int enable)
}
static struct ftrace_ops *
+ftrace_find_tramp_ops_any(struct dyn_ftrace *rec)
+{
+ struct ftrace_ops *op;
+ unsigned long ip = rec->ip;
+
+ do_for_each_ftrace_op(op, ftrace_ops_list) {
+
+ if (!op->trampoline)
+ continue;
+
+ if (hash_contains_ip(ip, op->func_hash))
+ return op;
+ } while_for_each_ftrace_op(op);
+
+ return NULL;
+}
+
+static struct ftrace_ops *
ftrace_find_tramp_ops_curr(struct dyn_ftrace *rec)
{
struct ftrace_ops *op;
+ unsigned long ip = rec->ip;
- /* Removed ops need to be tested first */
- if (removed_ops && removed_ops->tramp_hash) {
- if (ftrace_lookup_ip(removed_ops->tramp_hash, rec->ip))
+ /*
+ * Need to check removed ops first.
+ * If they are being removed, and this rec has a tramp,
+ * and this rec is in the ops list, then it would be the
+ * one with the tramp.
+ */
+ if (removed_ops) {
+ if (hash_contains_ip(ip, &removed_ops->old_hash))
return removed_ops;
}
+ /*
+ * Need to find the current trampoline for a rec.
+ * Now, a trampoline is only attached to a rec if there
+ * was a single 'ops' attached to it. But this can be called
+ * when we are adding another op to the rec or removing the
+ * current one. Thus, if the op is being added, we can
+ * ignore it because it hasn't attached itself to the rec
+ * yet. That means we just need to find the op that has a
+ * trampoline and is not beeing added.
+ */
do_for_each_ftrace_op(op, ftrace_ops_list) {
- if (!op->tramp_hash)
+
+ if (!op->trampoline)
+ continue;
+
+ /*
+ * If the ops is being added, it hasn't gotten to
+ * the point to be removed from this tree yet.
+ */
+ if (op->flags & FTRACE_OPS_FL_ADDING)
continue;
- if (ftrace_lookup_ip(op->tramp_hash, rec->ip))
+ /*
+ * If the ops is not being added and has a trampoline,
+ * then it must be the one that we want!
+ */
+ if (hash_contains_ip(ip, op->func_hash))
+ return op;
+
+ /* If the ops is being modified, it may be in the old hash. */
+ if ((op->flags & FTRACE_OPS_FL_MODIFYING) &&
+ hash_contains_ip(ip, &op->old_hash))
return op;
} while_for_each_ftrace_op(op);
@@ -1868,10 +1961,11 @@ static struct ftrace_ops *
ftrace_find_tramp_ops_new(struct dyn_ftrace *rec)
{
struct ftrace_ops *op;
+ unsigned long ip = rec->ip;
do_for_each_ftrace_op(op, ftrace_ops_list) {
/* pass rec in as regs to have non-NULL val */
- if (ftrace_ops_test(op, rec->ip, rec))
+ if (hash_contains_ip(ip, op->func_hash))
return op;
} while_for_each_ftrace_op(op);
@@ -1896,8 +1990,8 @@ unsigned long ftrace_get_addr_new(struct dyn_ftrace *rec)
if (rec->flags & FTRACE_FL_TRAMP) {
ops = ftrace_find_tramp_ops_new(rec);
if (FTRACE_WARN_ON(!ops || !ops->trampoline)) {
- pr_warning("Bad trampoline accounting at: %p (%pS)\n",
- (void *)rec->ip, (void *)rec->ip);
+ pr_warn("Bad trampoline accounting at: %p (%pS) (%lx)\n",
+ (void *)rec->ip, (void *)rec->ip, rec->flags);
/* Ftrace is shutting down, return anything */
return (unsigned long)FTRACE_ADDR;
}
@@ -1964,7 +2058,7 @@ __ftrace_replace_code(struct dyn_ftrace *rec, int enable)
return ftrace_make_call(rec, ftrace_addr);
case FTRACE_UPDATE_MAKE_NOP:
- return ftrace_make_nop(NULL, rec, ftrace_addr);
+ return ftrace_make_nop(NULL, rec, ftrace_old_addr);
case FTRACE_UPDATE_MODIFY_CALL:
return ftrace_modify_call(rec, ftrace_old_addr, ftrace_addr);
@@ -2178,89 +2272,6 @@ void __weak arch_ftrace_update_code(int command)
ftrace_run_stop_machine(command);
}
-static int ftrace_save_ops_tramp_hash(struct ftrace_ops *ops)
-{
- struct ftrace_page *pg;
- struct dyn_ftrace *rec;
- int size, bits;
- int ret;
-
- size = ops->nr_trampolines;
- bits = 0;
- /*
- * Make the hash size about 1/2 the # found
- */
- for (size /= 2; size; size >>= 1)
- bits++;
-
- ops->tramp_hash = alloc_ftrace_hash(bits);
- /*
- * TODO: a failed allocation is going to screw up
- * the accounting of what needs to be modified
- * and not. For now, we kill ftrace if we fail
- * to allocate here. But there are ways around this,
- * but that will take a little more work.
- */
- if (!ops->tramp_hash)
- return -ENOMEM;
-
- do_for_each_ftrace_rec(pg, rec) {
- if (ftrace_rec_count(rec) == 1 &&
- ftrace_ops_test(ops, rec->ip, rec)) {
-
- /*
- * If another ops adds to a rec, the rec will
- * lose its trampoline and never get it back
- * until all ops are off of it.
- */
- if (!(rec->flags & FTRACE_FL_TRAMP))
- continue;
-
- /* This record had better have a trampoline */
- if (FTRACE_WARN_ON(!(rec->flags & FTRACE_FL_TRAMP_EN)))
- return -1;
-
- ret = add_hash_entry(ops->tramp_hash, rec->ip);
- if (ret < 0)
- return ret;
- }
- } while_for_each_ftrace_rec();
-
- /* The number of recs in the hash must match nr_trampolines */
- FTRACE_WARN_ON(ops->tramp_hash->count != ops->nr_trampolines);
-
- return 0;
-}
-
-static int ftrace_save_tramp_hashes(void)
-{
- struct ftrace_ops *op;
- int ret;
-
- /*
- * Now that any trampoline is being used, we need to save the
- * hashes for the ops that have them. This allows the mapping
- * back from the record to the ops that has the trampoline to
- * know what code is being replaced. Modifying code must always
- * verify what it is changing.
- */
- do_for_each_ftrace_op(op, ftrace_ops_list) {
-
- /* The tramp_hash is recreated each time. */
- free_ftrace_hash(op->tramp_hash);
- op->tramp_hash = NULL;
-
- if (op->nr_trampolines) {
- ret = ftrace_save_ops_tramp_hash(op);
- if (ret)
- return ret;
- }
-
- } while_for_each_ftrace_op(op);
-
- return 0;
-}
-
static void ftrace_run_update_code(int command)
{
int ret;
@@ -2280,9 +2291,13 @@ static void ftrace_run_update_code(int command)
ret = ftrace_arch_code_modify_post_process();
FTRACE_WARN_ON(ret);
+}
- ret = ftrace_save_tramp_hashes();
- FTRACE_WARN_ON(ret);
+static void ftrace_run_modify_code(struct ftrace_ops *ops, int command)
+{
+ ops->flags |= FTRACE_OPS_FL_MODIFYING;
+ ftrace_run_update_code(command);
+ ops->flags &= ~FTRACE_OPS_FL_MODIFYING;
}
static ftrace_func_t saved_ftrace_func;
@@ -2306,6 +2321,13 @@ static void ftrace_startup_enable(int command)
ftrace_run_update_code(command);
}
+static void ftrace_startup_all(int command)
+{
+ update_all_ops = true;
+ ftrace_startup_enable(command);
+ update_all_ops = false;
+}
+
static int ftrace_startup(struct ftrace_ops *ops, int command)
{
int ret;
@@ -2320,12 +2342,22 @@ static int ftrace_startup(struct ftrace_ops *ops, int command)
ftrace_start_up++;
command |= FTRACE_UPDATE_CALLS;
- ops->flags |= FTRACE_OPS_FL_ENABLED;
+ /*
+ * Note that ftrace probes uses this to start up
+ * and modify functions it will probe. But we still
+ * set the ADDING flag for modification, as probes
+ * do not have trampolines. If they add them in the
+ * future, then the probes will need to distinguish
+ * between adding and updating probes.
+ */
+ ops->flags |= FTRACE_OPS_FL_ENABLED | FTRACE_OPS_FL_ADDING;
ftrace_hash_rec_enable(ops, 1);
ftrace_startup_enable(command);
+ ops->flags &= ~FTRACE_OPS_FL_ADDING;
+
return 0;
}
@@ -2375,11 +2407,35 @@ static int ftrace_shutdown(struct ftrace_ops *ops, int command)
* If the ops uses a trampoline, then it needs to be
* tested first on update.
*/
+ ops->flags |= FTRACE_OPS_FL_REMOVING;
removed_ops = ops;
+ /* The trampoline logic checks the old hashes */
+ ops->old_hash.filter_hash = ops->func_hash->filter_hash;
+ ops->old_hash.notrace_hash = ops->func_hash->notrace_hash;
+
ftrace_run_update_code(command);
+ /*
+ * If there's no more ops registered with ftrace, run a
+ * sanity check to make sure all rec flags are cleared.
+ */
+ if (ftrace_ops_list == &ftrace_list_end) {
+ struct ftrace_page *pg;
+ struct dyn_ftrace *rec;
+
+ do_for_each_ftrace_rec(pg, rec) {
+ if (FTRACE_WARN_ON_ONCE(rec->flags))
+ pr_warn(" %pS flags:%lx\n",
+ (void *)rec->ip, rec->flags);
+ } while_for_each_ftrace_rec();
+ }
+
+ ops->old_hash.filter_hash = NULL;
+ ops->old_hash.notrace_hash = NULL;
+
removed_ops = NULL;
+ ops->flags &= ~FTRACE_OPS_FL_REMOVING;
/*
* Dynamic ops may be freed, we must make sure that all
@@ -2436,8 +2492,8 @@ static inline int ops_traces_mod(struct ftrace_ops *ops)
* Filter_hash being empty will default to trace module.
* But notrace hash requires a test of individual module functions.
*/
- return ftrace_hash_empty(ops->filter_hash) &&
- ftrace_hash_empty(ops->notrace_hash);
+ return ftrace_hash_empty(ops->func_hash->filter_hash) &&
+ ftrace_hash_empty(ops->func_hash->notrace_hash);
}
/*
@@ -2459,12 +2515,12 @@ ops_references_rec(struct ftrace_ops *ops, struct dyn_ftrace *rec)
return 0;
/* The function must be in the filter */
- if (!ftrace_hash_empty(ops->filter_hash) &&
- !ftrace_lookup_ip(ops->filter_hash, rec->ip))
+ if (!ftrace_hash_empty(ops->func_hash->filter_hash) &&
+ !ftrace_lookup_ip(ops->func_hash->filter_hash, rec->ip))
return 0;
/* If in notrace hash, we ignore it too */
- if (ftrace_lookup_ip(ops->notrace_hash, rec->ip))
+ if (ftrace_lookup_ip(ops->func_hash->notrace_hash, rec->ip))
return 0;
return 1;
@@ -2785,10 +2841,10 @@ t_next(struct seq_file *m, void *v, loff_t *pos)
} else {
rec = &iter->pg->records[iter->idx++];
if (((iter->flags & FTRACE_ITER_FILTER) &&
- !(ftrace_lookup_ip(ops->filter_hash, rec->ip))) ||
+ !(ftrace_lookup_ip(ops->func_hash->filter_hash, rec->ip))) ||
((iter->flags & FTRACE_ITER_NOTRACE) &&
- !ftrace_lookup_ip(ops->notrace_hash, rec->ip)) ||
+ !ftrace_lookup_ip(ops->func_hash->notrace_hash, rec->ip)) ||
((iter->flags & FTRACE_ITER_ENABLED) &&
!(rec->flags & FTRACE_FL_ENABLED))) {
@@ -2837,9 +2893,9 @@ static void *t_start(struct seq_file *m, loff_t *pos)
* functions are enabled.
*/
if ((iter->flags & FTRACE_ITER_FILTER &&
- ftrace_hash_empty(ops->filter_hash)) ||
+ ftrace_hash_empty(ops->func_hash->filter_hash)) ||
(iter->flags & FTRACE_ITER_NOTRACE &&
- ftrace_hash_empty(ops->notrace_hash))) {
+ ftrace_hash_empty(ops->func_hash->notrace_hash))) {
if (*pos > 0)
return t_hash_start(m, pos);
iter->flags |= FTRACE_ITER_PRINTALL;
@@ -2904,8 +2960,8 @@ static int t_show(struct seq_file *m, void *v)
if (rec->flags & FTRACE_FL_TRAMP_EN) {
struct ftrace_ops *ops;
- ops = ftrace_find_tramp_ops_curr(rec);
- if (ops && ops->trampoline)
+ ops = ftrace_find_tramp_ops_any(rec);
+ if (ops)
seq_printf(m, "\ttramp: %pS",
(void *)ops->trampoline);
else
@@ -3001,12 +3057,12 @@ ftrace_regex_open(struct ftrace_ops *ops, int flag,
iter->ops = ops;
iter->flags = flag;
- mutex_lock(&ops->regex_lock);
+ mutex_lock(&ops->func_hash->regex_lock);
if (flag & FTRACE_ITER_NOTRACE)
- hash = ops->notrace_hash;
+ hash = ops->func_hash->notrace_hash;
else
- hash = ops->filter_hash;
+ hash = ops->func_hash->filter_hash;
if (file->f_mode & FMODE_WRITE) {
const int size_bits = FTRACE_HASH_DEFAULT_BITS;
@@ -3041,7 +3097,7 @@ ftrace_regex_open(struct ftrace_ops *ops, int flag,
file->private_data = iter;
out_unlock:
- mutex_unlock(&ops->regex_lock);
+ mutex_unlock(&ops->func_hash->regex_lock);
return ret;
}
@@ -3279,7 +3335,7 @@ static struct ftrace_ops trace_probe_ops __read_mostly =
{
.func = function_trace_probe_call,
.flags = FTRACE_OPS_FL_INITIALIZED,
- INIT_REGEX_LOCK(trace_probe_ops)
+ INIT_OPS_HASH(trace_probe_ops)
};
static int ftrace_probe_registered;
@@ -3292,7 +3348,7 @@ static void __enable_ftrace_function_probe(void)
if (ftrace_probe_registered) {
/* still need to update the function call sites */
if (ftrace_enabled)
- ftrace_run_update_code(FTRACE_UPDATE_CALLS);
+ ftrace_run_modify_code(&trace_probe_ops, FTRACE_UPDATE_CALLS);
return;
}
@@ -3342,7 +3398,8 @@ register_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops,
void *data)
{
struct ftrace_func_probe *entry;
- struct ftrace_hash **orig_hash = &trace_probe_ops.filter_hash;
+ struct ftrace_hash **orig_hash = &trace_probe_ops.func_hash->filter_hash;
+ struct ftrace_hash *old_hash = *orig_hash;
struct ftrace_hash *hash;
struct ftrace_page *pg;
struct dyn_ftrace *rec;
@@ -3359,9 +3416,9 @@ register_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops,
if (WARN_ON(not))
return -EINVAL;
- mutex_lock(&trace_probe_ops.regex_lock);
+ mutex_lock(&trace_probe_ops.func_hash->regex_lock);
- hash = alloc_and_copy_ftrace_hash(FTRACE_HASH_DEFAULT_BITS, *orig_hash);
+ hash = alloc_and_copy_ftrace_hash(FTRACE_HASH_DEFAULT_BITS, old_hash);
if (!hash) {
count = -ENOMEM;
goto out;
@@ -3420,7 +3477,9 @@ register_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops,
} while_for_each_ftrace_rec();
ret = ftrace_hash_move(&trace_probe_ops, 1, orig_hash, hash);
- if (ret < 0)
+ if (!ret)
+ free_ftrace_hash_rcu(old_hash);
+ else
count = ret;
__enable_ftrace_function_probe();
@@ -3428,7 +3487,7 @@ register_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops,
out_unlock:
mutex_unlock(&ftrace_lock);
out:
- mutex_unlock(&trace_probe_ops.regex_lock);
+ mutex_unlock(&trace_probe_ops.func_hash->regex_lock);
free_ftrace_hash(hash);
return count;
@@ -3446,7 +3505,8 @@ __unregister_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops,
struct ftrace_func_entry *rec_entry;
struct ftrace_func_probe *entry;
struct ftrace_func_probe *p;
- struct ftrace_hash **orig_hash = &trace_probe_ops.filter_hash;
+ struct ftrace_hash **orig_hash = &trace_probe_ops.func_hash->filter_hash;
+ struct ftrace_hash *old_hash = *orig_hash;
struct list_head free_list;
struct ftrace_hash *hash;
struct hlist_node *tmp;
@@ -3454,6 +3514,7 @@ __unregister_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops,
int type = MATCH_FULL;
int i, len = 0;
char *search;
+ int ret;
if (glob && (strcmp(glob, "*") == 0 || !strlen(glob)))
glob = NULL;
@@ -3468,7 +3529,7 @@ __unregister_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops,
return;
}
- mutex_lock(&trace_probe_ops.regex_lock);
+ mutex_lock(&trace_probe_ops.func_hash->regex_lock);
hash = alloc_and_copy_ftrace_hash(FTRACE_HASH_DEFAULT_BITS, *orig_hash);
if (!hash)
@@ -3512,8 +3573,11 @@ __unregister_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops,
* Remove after the disable is called. Otherwise, if the last
* probe is removed, a null hash means *all enabled*.
*/
- ftrace_hash_move(&trace_probe_ops, 1, orig_hash, hash);
+ ret = ftrace_hash_move(&trace_probe_ops, 1, orig_hash, hash);
synchronize_sched();
+ if (!ret)
+ free_ftrace_hash_rcu(old_hash);
+
list_for_each_entry_safe(entry, p, &free_list, free_list) {
list_del(&entry->free_list);
ftrace_free_entry(entry);
@@ -3521,7 +3585,7 @@ __unregister_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops,
mutex_unlock(&ftrace_lock);
out_unlock:
- mutex_unlock(&trace_probe_ops.regex_lock);
+ mutex_unlock(&trace_probe_ops.func_hash->regex_lock);
free_ftrace_hash(hash);
}
@@ -3703,7 +3767,7 @@ ftrace_match_addr(struct ftrace_hash *hash, unsigned long ip, int remove)
static void ftrace_ops_update_code(struct ftrace_ops *ops)
{
if (ops->flags & FTRACE_OPS_FL_ENABLED && ftrace_enabled)
- ftrace_run_update_code(FTRACE_UPDATE_CALLS);
+ ftrace_run_modify_code(ops, FTRACE_UPDATE_CALLS);
}
static int
@@ -3711,18 +3775,19 @@ ftrace_set_hash(struct ftrace_ops *ops, unsigned char *buf, int len,
unsigned long ip, int remove, int reset, int enable)
{
struct ftrace_hash **orig_hash;
+ struct ftrace_hash *old_hash;
struct ftrace_hash *hash;
int ret;
if (unlikely(ftrace_disabled))
return -ENODEV;
- mutex_lock(&ops->regex_lock);
+ mutex_lock(&ops->func_hash->regex_lock);
if (enable)
- orig_hash = &ops->filter_hash;
+ orig_hash = &ops->func_hash->filter_hash;
else
- orig_hash = &ops->notrace_hash;
+ orig_hash = &ops->func_hash->notrace_hash;
if (reset)
hash = alloc_ftrace_hash(FTRACE_HASH_DEFAULT_BITS);
@@ -3745,14 +3810,16 @@ ftrace_set_hash(struct ftrace_ops *ops, unsigned char *buf, int len,
}
mutex_lock(&ftrace_lock);
+ old_hash = *orig_hash;
ret = ftrace_hash_move(ops, enable, orig_hash, hash);
- if (!ret)
+ if (!ret) {
ftrace_ops_update_code(ops);
-
+ free_ftrace_hash_rcu(old_hash);
+ }
mutex_unlock(&ftrace_lock);
out_regex_unlock:
- mutex_unlock(&ops->regex_lock);
+ mutex_unlock(&ops->func_hash->regex_lock);
free_ftrace_hash(hash);
return ret;
@@ -3957,6 +4024,7 @@ int ftrace_regex_release(struct inode *inode, struct file *file)
struct seq_file *m = (struct seq_file *)file->private_data;
struct ftrace_iterator *iter;
struct ftrace_hash **orig_hash;
+ struct ftrace_hash *old_hash;
struct trace_parser *parser;
int filter_hash;
int ret;
@@ -3975,26 +4043,28 @@ int ftrace_regex_release(struct inode *inode, struct file *file)
trace_parser_put(parser);
- mutex_lock(&iter->ops->regex_lock);
+ mutex_lock(&iter->ops->func_hash->regex_lock);
if (file->f_mode & FMODE_WRITE) {
filter_hash = !!(iter->flags & FTRACE_ITER_FILTER);
if (filter_hash)
- orig_hash = &iter->ops->filter_hash;
+ orig_hash = &iter->ops->func_hash->filter_hash;
else
- orig_hash = &iter->ops->notrace_hash;
+ orig_hash = &iter->ops->func_hash->notrace_hash;
mutex_lock(&ftrace_lock);
+ old_hash = *orig_hash;
ret = ftrace_hash_move(iter->ops, filter_hash,
orig_hash, iter->hash);
- if (!ret)
+ if (!ret) {
ftrace_ops_update_code(iter->ops);
-
+ free_ftrace_hash_rcu(old_hash);
+ }
mutex_unlock(&ftrace_lock);
}
- mutex_unlock(&iter->ops->regex_lock);
+ mutex_unlock(&iter->ops->func_hash->regex_lock);
free_ftrace_hash(iter->hash);
kfree(iter);
@@ -4611,7 +4681,6 @@ void __init ftrace_init(void)
static struct ftrace_ops global_ops = {
.func = ftrace_stub,
.flags = FTRACE_OPS_FL_RECURSION_SAFE | FTRACE_OPS_FL_INITIALIZED,
- INIT_REGEX_LOCK(global_ops)
};
static int __init ftrace_nodyn_init(void)
@@ -4623,6 +4692,7 @@ core_initcall(ftrace_nodyn_init);
static inline int ftrace_init_dyn_debugfs(struct dentry *d_tracer) { return 0; }
static inline void ftrace_startup_enable(int command) { }
+static inline void ftrace_startup_all(int command) { }
/* Keep as macros so we do not need to define the commands */
# define ftrace_startup(ops, command) \
({ \
@@ -4713,7 +4783,7 @@ ftrace_ops_control_func(unsigned long ip, unsigned long parent_ip,
static struct ftrace_ops control_ops = {
.func = ftrace_ops_control_func,
.flags = FTRACE_OPS_FL_RECURSION_SAFE | FTRACE_OPS_FL_INITIALIZED,
- INIT_REGEX_LOCK(control_ops)
+ INIT_OPS_HASH(control_ops)
};
static inline void
@@ -4772,6 +4842,56 @@ static void ftrace_ops_no_ops(unsigned long ip, unsigned long parent_ip)
}
#endif
+/*
+ * If there's only one function registered but it does not support
+ * recursion, this function will be called by the mcount trampoline.
+ * This function will handle recursion protection.
+ */
+static void ftrace_ops_recurs_func(unsigned long ip, unsigned long parent_ip,
+ struct ftrace_ops *op, struct pt_regs *regs)
+{
+ int bit;
+
+ bit = trace_test_and_set_recursion(TRACE_LIST_START, TRACE_LIST_MAX);
+ if (bit < 0)
+ return;
+
+ op->func(ip, parent_ip, op, regs);
+
+ trace_clear_recursion(bit);
+}
+
+/**
+ * ftrace_ops_get_func - get the function a trampoline should call
+ * @ops: the ops to get the function for
+ *
+ * Normally the mcount trampoline will call the ops->func, but there
+ * are times that it should not. For example, if the ops does not
+ * have its own recursion protection, then it should call the
+ * ftrace_ops_recurs_func() instead.
+ *
+ * Returns the function that the trampoline should call for @ops.
+ */
+ftrace_func_t ftrace_ops_get_func(struct ftrace_ops *ops)
+{
+ /*
+ * If this is a dynamic ops or we force list func,
+ * then it needs to call the list anyway.
+ */
+ if (ops->flags & FTRACE_OPS_FL_DYNAMIC || FTRACE_FORCE_LIST_FUNC)
+ return ftrace_ops_list_func;
+
+ /*
+ * If the func handles its own recursion, call it directly.
+ * Otherwise call the recursion protected function that
+ * will call the ftrace ops function.
+ */
+ if (!(ops->flags & FTRACE_OPS_FL_RECURSION_SAFE))
+ return ftrace_ops_recurs_func;
+
+ return ops->func;
+}
+
static void clear_ftrace_swapper(void)
{
struct task_struct *p;
@@ -4872,7 +4992,8 @@ static int ftrace_pid_add(int p)
set_ftrace_pid_task(pid);
ftrace_update_pid_func();
- ftrace_startup_enable(0);
+
+ ftrace_startup_all(0);
mutex_unlock(&ftrace_lock);
return 0;
@@ -4901,7 +5022,7 @@ static void ftrace_pid_reset(void)
}
ftrace_update_pid_func();
- ftrace_startup_enable(0);
+ ftrace_startup_all(0);
mutex_unlock(&ftrace_lock);
}
@@ -5145,6 +5266,17 @@ ftrace_enable_sysctl(struct ctl_table *table, int write,
#ifdef CONFIG_FUNCTION_GRAPH_TRACER
+static struct ftrace_ops graph_ops = {
+ .func = ftrace_stub,
+ .flags = FTRACE_OPS_FL_RECURSION_SAFE |
+ FTRACE_OPS_FL_INITIALIZED |
+ FTRACE_OPS_FL_STUB,
+#ifdef FTRACE_GRAPH_TRAMP_ADDR
+ .trampoline = FTRACE_GRAPH_TRAMP_ADDR,
+#endif
+ ASSIGN_OPS_HASH(graph_ops, &global_ops.local_hash)
+};
+
static int ftrace_graph_active;
int ftrace_graph_entry_stub(struct ftrace_graph_ent *trace)
@@ -5307,12 +5439,28 @@ static int ftrace_graph_entry_test(struct ftrace_graph_ent *trace)
*/
static void update_function_graph_func(void)
{
- if (ftrace_ops_list == &ftrace_list_end ||
- (ftrace_ops_list == &global_ops &&
- global_ops.next == &ftrace_list_end))
- ftrace_graph_entry = __ftrace_graph_entry;
- else
+ struct ftrace_ops *op;
+ bool do_test = false;
+
+ /*
+ * The graph and global ops share the same set of functions
+ * to test. If any other ops is on the list, then
+ * the graph tracing needs to test if its the function
+ * it should call.
+ */
+ do_for_each_ftrace_op(op, ftrace_ops_list) {
+ if (op != &global_ops && op != &graph_ops &&
+ op != &ftrace_list_end) {
+ do_test = true;
+ /* in double loop, break out with goto */
+ goto out;
+ }
+ } while_for_each_ftrace_op(op);
+ out:
+ if (do_test)
ftrace_graph_entry = ftrace_graph_entry_test;
+ else
+ ftrace_graph_entry = __ftrace_graph_entry;
}
static struct notifier_block ftrace_suspend_notifier = {
@@ -5353,16 +5501,7 @@ int register_ftrace_graph(trace_func_graph_ret_t retfunc,
ftrace_graph_entry = ftrace_graph_entry_test;
update_function_graph_func();
- /* Function graph doesn't use the .func field of global_ops */
- global_ops.flags |= FTRACE_OPS_FL_STUB;
-
-#ifdef CONFIG_DYNAMIC_FTRACE
- /* Optimize function graph calling (if implemented by arch) */
- if (FTRACE_GRAPH_TRAMP_ADDR != 0)
- global_ops.trampoline = FTRACE_GRAPH_TRAMP_ADDR;
-#endif
-
- ret = ftrace_startup(&global_ops, FTRACE_START_FUNC_RET);
+ ret = ftrace_startup(&graph_ops, FTRACE_START_FUNC_RET);
out:
mutex_unlock(&ftrace_lock);
@@ -5380,12 +5519,7 @@ void unregister_ftrace_graph(void)
ftrace_graph_return = (trace_func_graph_ret_t)ftrace_stub;
ftrace_graph_entry = ftrace_graph_entry_stub;
__ftrace_graph_entry = ftrace_graph_entry_stub;
- ftrace_shutdown(&global_ops, FTRACE_STOP_FUNC_RET);
- global_ops.flags &= ~FTRACE_OPS_FL_STUB;
-#ifdef CONFIG_DYNAMIC_FTRACE
- if (FTRACE_GRAPH_TRAMP_ADDR != 0)
- global_ops.trampoline = 0;
-#endif
+ ftrace_shutdown(&graph_ops, FTRACE_STOP_FUNC_RET);
unregister_pm_notifier(&ftrace_suspend_notifier);
unregister_trace_sched_switch(ftrace_graph_probe_sched_switch, NULL);
diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c
index afb04b9b818a..2d75c94ae87d 100644
--- a/kernel/trace/ring_buffer.c
+++ b/kernel/trace/ring_buffer.c
@@ -626,8 +626,22 @@ int ring_buffer_poll_wait(struct ring_buffer *buffer, int cpu,
work = &cpu_buffer->irq_work;
}
- work->waiters_pending = true;
poll_wait(filp, &work->waiters, poll_table);
+ work->waiters_pending = true;
+ /*
+ * There's a tight race between setting the waiters_pending and
+ * checking if the ring buffer is empty. Once the waiters_pending bit
+ * is set, the next event will wake the task up, but we can get stuck
+ * if there's only a single event in.
+ *
+ * FIXME: Ideally, we need a memory barrier on the writer side as well,
+ * but adding a memory barrier to all events will cause too much of a
+ * performance hit in the fast path. We only need a memory barrier when
+ * the buffer goes from empty to having content. But as this race is
+ * extremely small, and it's not a problem if another event comes in, we
+ * will fix it later.
+ */
+ smp_mb();
if ((cpu == RING_BUFFER_ALL_CPUS && !ring_buffer_empty(buffer)) ||
(cpu != RING_BUFFER_ALL_CPUS && !ring_buffer_empty_cpu(buffer, cpu)))
@@ -3345,7 +3359,7 @@ static void rb_iter_reset(struct ring_buffer_iter *iter)
iter->head = cpu_buffer->reader_page->read;
iter->cache_reader_page = iter->head_page;
- iter->cache_read = iter->head;
+ iter->cache_read = cpu_buffer->read;
if (iter->head)
iter->read_stamp = cpu_buffer->read_stamp;
diff --git a/kernel/trace/ring_buffer_benchmark.c b/kernel/trace/ring_buffer_benchmark.c
index 0434ff1b808e..3f9e328c30b5 100644
--- a/kernel/trace/ring_buffer_benchmark.c
+++ b/kernel/trace/ring_buffer_benchmark.c
@@ -205,7 +205,6 @@ static void ring_buffer_consumer(void)
break;
schedule();
- __set_current_state(TASK_RUNNING);
}
reader_finish = 0;
complete(&read_done);
@@ -379,7 +378,6 @@ static int ring_buffer_consumer_thread(void *arg)
break;
schedule();
- __set_current_state(TASK_RUNNING);
}
__set_current_state(TASK_RUNNING);
@@ -407,7 +405,6 @@ static int ring_buffer_producer_thread(void *arg)
trace_printk("Sleeping for 10 secs\n");
set_current_state(TASK_INTERRUPTIBLE);
schedule_timeout(HZ * SLEEP_TIME);
- __set_current_state(TASK_RUNNING);
}
if (kill_test)
diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c
index ef06ce7e9cf8..0cc51edde3a8 100644
--- a/kernel/trace/trace_events.c
+++ b/kernel/trace/trace_events.c
@@ -2513,8 +2513,11 @@ static __init int event_test_thread(void *unused)
kfree(test_malloc);
set_current_state(TASK_INTERRUPTIBLE);
- while (!kthread_should_stop())
+ while (!kthread_should_stop()) {
schedule();
+ set_current_state(TASK_INTERRUPTIBLE);
+ }
+ __set_current_state(TASK_RUNNING);
return 0;
}
diff --git a/kernel/trace/trace_selftest.c b/kernel/trace/trace_selftest.c
index 5ef60499dc8e..b0f86ea77881 100644
--- a/kernel/trace/trace_selftest.c
+++ b/kernel/trace/trace_selftest.c
@@ -382,6 +382,8 @@ static int trace_selftest_startup_dynamic_tracing(struct tracer *trace,
/* check the trace buffer */
ret = trace_test_buffer(&tr->trace_buffer, &count);
+
+ ftrace_enabled = 1;
tracing_start();
/* we should only have one item */
@@ -679,6 +681,8 @@ trace_selftest_startup_function(struct tracer *trace, struct trace_array *tr)
/* check the trace buffer */
ret = trace_test_buffer(&tr->trace_buffer, &count);
+
+ ftrace_enabled = 1;
trace->reset(tr);
tracing_start();
@@ -1025,6 +1029,12 @@ trace_selftest_startup_nop(struct tracer *trace, struct trace_array *tr)
#endif
#ifdef CONFIG_SCHED_TRACER
+
+struct wakeup_test_data {
+ struct completion is_ready;
+ int go;
+};
+
static int trace_wakeup_test_thread(void *data)
{
/* Make this a -deadline thread */
@@ -1034,51 +1044,56 @@ static int trace_wakeup_test_thread(void *data)
.sched_deadline = 10000000ULL,
.sched_period = 10000000ULL
};
- struct completion *x = data;
+ struct wakeup_test_data *x = data;
sched_setattr(current, &attr);
/* Make it know we have a new prio */
- complete(x);
+ complete(&x->is_ready);
/* now go to sleep and let the test wake us up */
set_current_state(TASK_INTERRUPTIBLE);
- schedule();
+ while (!x->go) {
+ schedule();
+ set_current_state(TASK_INTERRUPTIBLE);
+ }
- complete(x);
+ complete(&x->is_ready);
+
+ set_current_state(TASK_INTERRUPTIBLE);
/* we are awake, now wait to disappear */
while (!kthread_should_stop()) {
- /*
- * This will likely be the system top priority
- * task, do short sleeps to let others run.
- */
- msleep(100);
+ schedule();
+ set_current_state(TASK_INTERRUPTIBLE);
}
+ __set_current_state(TASK_RUNNING);
+
return 0;
}
-
int
trace_selftest_startup_wakeup(struct tracer *trace, struct trace_array *tr)
{
unsigned long save_max = tr->max_latency;
struct task_struct *p;
- struct completion is_ready;
+ struct wakeup_test_data data;
unsigned long count;
int ret;
- init_completion(&is_ready);
+ memset(&data, 0, sizeof(data));
+
+ init_completion(&data.is_ready);
/* create a -deadline thread */
- p = kthread_run(trace_wakeup_test_thread, &is_ready, "ftrace-test");
+ p = kthread_run(trace_wakeup_test_thread, &data, "ftrace-test");
if (IS_ERR(p)) {
printk(KERN_CONT "Failed to create ftrace wakeup test thread ");
return -1;
}
/* make sure the thread is running at -deadline policy */
- wait_for_completion(&is_ready);
+ wait_for_completion(&data.is_ready);
/* start the tracing */
ret = tracer_init(trace, tr);
@@ -1099,18 +1114,20 @@ trace_selftest_startup_wakeup(struct tracer *trace, struct trace_array *tr)
msleep(100);
}
- init_completion(&is_ready);
+ init_completion(&data.is_ready);
+
+ data.go = 1;
+ /* memory barrier is in the wake_up_process() */
wake_up_process(p);
/* Wait for the task to wake up */
- wait_for_completion(&is_ready);
+ wait_for_completion(&data.is_ready);
/* stop the tracing. */
tracing_stop();
/* check both trace buffers */
ret = trace_test_buffer(&tr->trace_buffer, NULL);
- printk("ret = %d\n", ret);
if (!ret)
ret = trace_test_buffer(&tr->max_buffer, &count);
diff --git a/kernel/trace/trace_stack.c b/kernel/trace/trace_stack.c
index 8a4e5cb66a4c..16eddb308c33 100644
--- a/kernel/trace/trace_stack.c
+++ b/kernel/trace/trace_stack.c
@@ -13,7 +13,6 @@
#include <linux/sysctl.h>
#include <linux/init.h>
#include <linux/fs.h>
-#include <linux/magic.h>
#include <asm/setup.h>
@@ -171,8 +170,7 @@ check_stack(unsigned long ip, unsigned long *stack)
i++;
}
- if ((current != &init_task &&
- *(end_of_stack(current)) != STACK_END_MAGIC)) {
+ if (task_stack_end_corrupted(current)) {
print_max_stack();
BUG();
}
diff --git a/kernel/trace/trace_syscalls.c b/kernel/trace/trace_syscalls.c
index 759d5e004517..4dc8b79c5f75 100644
--- a/kernel/trace/trace_syscalls.c
+++ b/kernel/trace/trace_syscalls.c
@@ -425,7 +425,7 @@ static void unreg_event_syscall_enter(struct ftrace_event_file *file,
return;
mutex_lock(&syscall_trace_lock);
tr->sys_refcount_enter--;
- rcu_assign_pointer(tr->enter_syscall_files[num], NULL);
+ RCU_INIT_POINTER(tr->enter_syscall_files[num], NULL);
if (!tr->sys_refcount_enter)
unregister_trace_sys_enter(ftrace_syscall_enter, tr);
mutex_unlock(&syscall_trace_lock);
@@ -463,7 +463,7 @@ static void unreg_event_syscall_exit(struct ftrace_event_file *file,
return;
mutex_lock(&syscall_trace_lock);
tr->sys_refcount_exit--;
- rcu_assign_pointer(tr->exit_syscall_files[num], NULL);
+ RCU_INIT_POINTER(tr->exit_syscall_files[num], NULL);
if (!tr->sys_refcount_exit)
unregister_trace_sys_exit(ftrace_syscall_exit, tr);
mutex_unlock(&syscall_trace_lock);
diff --git a/kernel/watchdog.c b/kernel/watchdog.c
index dca8cae7e55d..70bf11815f84 100644
--- a/kernel/watchdog.c
+++ b/kernel/watchdog.c
@@ -15,11 +15,6 @@
#include <linux/cpu.h>
#include <linux/nmi.h>
#include <linux/init.h>
-#include <linux/delay.h>
-#include <linux/freezer.h>
-#include <linux/kthread.h>
-#include <linux/lockdep.h>
-#include <linux/notifier.h>
#include <linux/module.h>
#include <linux/sysctl.h>
#include <linux/smpboot.h>
@@ -47,6 +42,7 @@ static DEFINE_PER_CPU(bool, softlockup_touch_sync);
static DEFINE_PER_CPU(bool, soft_watchdog_warn);
static DEFINE_PER_CPU(unsigned long, hrtimer_interrupts);
static DEFINE_PER_CPU(unsigned long, soft_lockup_hrtimer_cnt);
+static DEFINE_PER_CPU(struct task_struct *, softlockup_task_ptr_saved);
#ifdef CONFIG_HARDLOCKUP_DETECTOR
static DEFINE_PER_CPU(bool, hard_watchdog_warn);
static DEFINE_PER_CPU(bool, watchdog_nmi_touch);
@@ -63,6 +59,25 @@ static unsigned long soft_lockup_nmi_warn;
static int hardlockup_panic =
CONFIG_BOOTPARAM_HARDLOCKUP_PANIC_VALUE;
+static bool hardlockup_detector_enabled = true;
+/*
+ * We may not want to enable hard lockup detection by default in all cases,
+ * for example when running the kernel as a guest on a hypervisor. In these
+ * cases this function can be called to disable hard lockup detection. This
+ * function should only be executed once by the boot processor before the
+ * kernel command line parameters are parsed, because otherwise it is not
+ * possible to override this in hardlockup_panic_setup().
+ */
+void watchdog_enable_hardlockup_detector(bool val)
+{
+ hardlockup_detector_enabled = val;
+}
+
+bool watchdog_hardlockup_detector_is_enabled(void)
+{
+ return hardlockup_detector_enabled;
+}
+
static int __init hardlockup_panic_setup(char *str)
{
if (!strncmp(str, "panic", 5))
@@ -71,6 +86,14 @@ static int __init hardlockup_panic_setup(char *str)
hardlockup_panic = 0;
else if (!strncmp(str, "0", 1))
watchdog_user_enabled = 0;
+ else if (!strncmp(str, "1", 1) || !strncmp(str, "2", 1)) {
+ /*
+ * Setting 'nmi_watchdog=1' or 'nmi_watchdog=2' (legacy option)
+ * has the same effect.
+ */
+ watchdog_user_enabled = 1;
+ watchdog_enable_hardlockup_detector(true);
+ }
return 1;
}
__setup("nmi_watchdog=", hardlockup_panic_setup);
@@ -333,8 +356,22 @@ static enum hrtimer_restart watchdog_timer_fn(struct hrtimer *hrtimer)
return HRTIMER_RESTART;
/* only warn once */
- if (__this_cpu_read(soft_watchdog_warn) == true)
+ if (__this_cpu_read(soft_watchdog_warn) == true) {
+ /*
+ * When multiple processes are causing softlockups the
+ * softlockup detector only warns on the first one
+ * because the code relies on a full quiet cycle to
+ * re-arm. The second process prevents the quiet cycle
+ * and never gets reported. Use task pointers to detect
+ * this.
+ */
+ if (__this_cpu_read(softlockup_task_ptr_saved) !=
+ current) {
+ __this_cpu_write(soft_watchdog_warn, false);
+ __touch_watchdog();
+ }
return HRTIMER_RESTART;
+ }
if (softlockup_all_cpu_backtrace) {
/* Prevent multiple soft-lockup reports if one cpu is already
@@ -350,6 +387,7 @@ static enum hrtimer_restart watchdog_timer_fn(struct hrtimer *hrtimer)
pr_emerg("BUG: soft lockup - CPU#%d stuck for %us! [%s:%d]\n",
smp_processor_id(), duration,
current->comm, task_pid_nr(current));
+ __this_cpu_write(softlockup_task_ptr_saved, current);
print_modules();
print_irqtrace_events(current);
if (regs)
@@ -454,6 +492,15 @@ static int watchdog_nmi_enable(unsigned int cpu)
struct perf_event_attr *wd_attr;
struct perf_event *event = per_cpu(watchdog_ev, cpu);
+ /*
+ * Some kernels need to default hard lockup detection to
+ * 'disabled', for example a guest on a hypervisor.
+ */
+ if (!watchdog_hardlockup_detector_is_enabled()) {
+ event = ERR_PTR(-ENOENT);
+ goto handle_err;
+ }
+
/* is it already setup and enabled? */
if (event && event->state > PERF_EVENT_STATE_OFF)
goto out;
@@ -468,6 +515,7 @@ static int watchdog_nmi_enable(unsigned int cpu)
/* Try to register using hardware perf events */
event = perf_event_create_kernel_counter(wd_attr, cpu, NULL, watchdog_overflow_callback, NULL);
+handle_err:
/* save cpu0 error for future comparision */
if (cpu == 0 && IS_ERR(event))
cpu0_err = PTR_ERR(event);
@@ -514,7 +562,10 @@ static void watchdog_nmi_disable(unsigned int cpu)
/* should be in cleanup, but blocks oprofile */
perf_event_release_kernel(event);
}
- return;
+ if (cpu == 0) {
+ /* watchdog_nmi_enable() expects this to be zero initially. */
+ cpu0_err = 0;
+ }
}
#else
static int watchdog_nmi_enable(unsigned int cpu) { return 0; }
@@ -610,11 +661,13 @@ int proc_dowatchdog(struct ctl_table *table, int write,
void __user *buffer, size_t *lenp, loff_t *ppos)
{
int err, old_thresh, old_enabled;
+ bool old_hardlockup;
static DEFINE_MUTEX(watchdog_proc_mutex);
mutex_lock(&watchdog_proc_mutex);
old_thresh = ACCESS_ONCE(watchdog_thresh);
old_enabled = ACCESS_ONCE(watchdog_user_enabled);
+ old_hardlockup = watchdog_hardlockup_detector_is_enabled();
err = proc_dointvec_minmax(table, write, buffer, lenp, ppos);
if (err || !write)
@@ -626,15 +679,22 @@ int proc_dowatchdog(struct ctl_table *table, int write,
* disabled. The 'watchdog_running' variable check in
* watchdog_*_all_cpus() function takes care of this.
*/
- if (watchdog_user_enabled && watchdog_thresh)
+ if (watchdog_user_enabled && watchdog_thresh) {
+ /*
+ * Prevent a change in watchdog_thresh accidentally overriding
+ * the enablement of the hardlockup detector.
+ */
+ if (watchdog_user_enabled != old_enabled)
+ watchdog_enable_hardlockup_detector(true);
err = watchdog_enable_all_cpus(old_thresh != watchdog_thresh);
- else
+ } else
watchdog_disable_all_cpus();
/* Restore old values on failure */
if (err) {
watchdog_thresh = old_thresh;
watchdog_user_enabled = old_enabled;
+ watchdog_enable_hardlockup_detector(old_hardlockup);
}
out:
mutex_unlock(&watchdog_proc_mutex);
diff --git a/kernel/workqueue.c b/kernel/workqueue.c
index 5dbe22aa3efd..09b685daee3d 100644
--- a/kernel/workqueue.c
+++ b/kernel/workqueue.c
@@ -2043,9 +2043,10 @@ __acquires(&pool->lock)
* kernels, where a requeueing work item waiting for something to
* happen could deadlock with stop_machine as such work item could
* indefinitely requeue itself while all other CPUs are trapped in
- * stop_machine.
+ * stop_machine. At the same time, report a quiescent RCU state so
+ * the same condition doesn't freeze RCU.
*/
- cond_resched();
+ cond_resched_rcu_qs();
spin_lock_irq(&pool->lock);