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-rw-r--r--kernel/bpf/bpf_local_storage.c2
-rw-r--r--kernel/bpf/btf.c5
-rw-r--r--kernel/bpf/cgroup_iter.c2
-rw-r--r--kernel/bpf/dispatcher.c22
-rw-r--r--kernel/bpf/memalloc.c18
-rw-r--r--kernel/bpf/percpu_freelist.c23
-rw-r--r--kernel/bpf/verifier.c32
-rw-r--r--kernel/cgroup/cgroup-internal.h1
-rw-r--r--kernel/cgroup/cgroup.c99
-rw-r--r--kernel/events/core.c207
-rw-r--r--kernel/events/hw_breakpoint_test.c4
-rw-r--r--kernel/events/ring_buffer.c2
-rw-r--r--kernel/fork.c26
-rw-r--r--kernel/gcov/clang.c2
-rw-r--r--kernel/gcov/gcc_4_7.c18
-rw-r--r--kernel/kcsan/core.c50
-rw-r--r--kernel/kprobes.c13
-rw-r--r--kernel/nsproxy.c23
-rw-r--r--kernel/power/hibernate.c2
-rw-r--r--kernel/printk/printk.c2
-rw-r--r--kernel/printk/printk_ringbuffer.c2
-rw-r--r--kernel/rcu/Kconfig8
-rw-r--r--kernel/rcu/rcu.h8
-rw-r--r--kernel/rcu/rcuscale.c69
-rw-r--r--kernel/rcu/rcutorture.c61
-rw-r--r--kernel/rcu/sync.c2
-rw-r--r--kernel/rcu/tasks.h2
-rw-r--r--kernel/rcu/tiny.c2
-rw-r--r--kernel/rcu/tree.c162
-rw-r--r--kernel/rcu/tree.h12
-rw-r--r--kernel/rcu/tree_exp.h2
-rw-r--r--kernel/rcu/tree_nocb.h259
-rw-r--r--kernel/rcu/tree_plugin.h5
-rw-r--r--kernel/rseq.c19
-rw-r--r--kernel/sched/core.c76
-rw-r--r--kernel/sched/cpufreq_schedutil.c30
-rw-r--r--kernel/sched/deadline.c4
-rw-r--r--kernel/sched/rt.c4
-rw-r--r--kernel/sched/sched.h32
-rw-r--r--kernel/sysctl.c30
-rw-r--r--kernel/trace/blktrace.c82
-rw-r--r--kernel/trace/bpf_trace.c2
-rw-r--r--kernel/trace/fprobe.c5
-rw-r--r--kernel/trace/ftrace.c21
-rw-r--r--kernel/trace/kprobe_event_gen_test.c66
-rw-r--r--kernel/trace/rethook.c4
-rw-r--r--kernel/trace/ring_buffer.c82
-rw-r--r--kernel/trace/synth_event_gen_test.c16
-rw-r--r--kernel/trace/trace.c23
-rw-r--r--kernel/trace/trace.h1
-rw-r--r--kernel/trace/trace_dynevent.c2
-rw-r--r--kernel/trace/trace_eprobe.c8
-rw-r--r--kernel/trace/trace_events.c13
-rw-r--r--kernel/trace/trace_events_hist.c7
-rw-r--r--kernel/trace/trace_events_synth.c7
-rw-r--r--kernel/trace/trace_events_user.c4
-rw-r--r--kernel/trace/trace_osnoise.c6
-rw-r--r--kernel/trace/trace_syscalls.c2
-rw-r--r--kernel/utsname_sysctl.c1
-rw-r--r--kernel/workqueue.c2
60 files changed, 1208 insertions, 488 deletions
diff --git a/kernel/bpf/bpf_local_storage.c b/kernel/bpf/bpf_local_storage.c
index 802fc15b0d73..f27fa5ba7d72 100644
--- a/kernel/bpf/bpf_local_storage.c
+++ b/kernel/bpf/bpf_local_storage.c
@@ -74,7 +74,7 @@ bpf_selem_alloc(struct bpf_local_storage_map *smap, void *owner,
gfp_flags | __GFP_NOWARN);
if (selem) {
if (value)
- memcpy(SDATA(selem)->data, value, smap->map.value_size);
+ copy_map_value(&smap->map, SDATA(selem)->data, value);
return selem;
}
diff --git a/kernel/bpf/btf.c b/kernel/bpf/btf.c
index eba603cec2c5..35c07afac924 100644
--- a/kernel/bpf/btf.c
+++ b/kernel/bpf/btf.c
@@ -4436,6 +4436,11 @@ static int btf_func_proto_check(struct btf_verifier_env *env,
return -EINVAL;
}
+ if (btf_type_is_resolve_source_only(ret_type)) {
+ btf_verifier_log_type(env, t, "Invalid return type");
+ return -EINVAL;
+ }
+
if (btf_type_needs_resolve(ret_type) &&
!env_type_is_resolved(env, ret_type_id)) {
err = btf_resolve(env, ret_type, ret_type_id);
diff --git a/kernel/bpf/cgroup_iter.c b/kernel/bpf/cgroup_iter.c
index 0d200a993489..9fcf09f2ef00 100644
--- a/kernel/bpf/cgroup_iter.c
+++ b/kernel/bpf/cgroup_iter.c
@@ -196,7 +196,7 @@ static int bpf_iter_attach_cgroup(struct bpf_prog *prog,
return -EINVAL;
if (fd)
- cgrp = cgroup_get_from_fd(fd);
+ cgrp = cgroup_v1v2_get_from_fd(fd);
else if (id)
cgrp = cgroup_get_from_id(id);
else /* walk the entire hierarchy by default. */
diff --git a/kernel/bpf/dispatcher.c b/kernel/bpf/dispatcher.c
index fa64b80b8bca..c19719f48ce0 100644
--- a/kernel/bpf/dispatcher.c
+++ b/kernel/bpf/dispatcher.c
@@ -4,6 +4,7 @@
#include <linux/hash.h>
#include <linux/bpf.h>
#include <linux/filter.h>
+#include <linux/static_call.h>
/* The BPF dispatcher is a multiway branch code generator. The
* dispatcher is a mechanism to avoid the performance penalty of an
@@ -104,17 +105,11 @@ static int bpf_dispatcher_prepare(struct bpf_dispatcher *d, void *image, void *b
static void bpf_dispatcher_update(struct bpf_dispatcher *d, int prev_num_progs)
{
- void *old, *new, *tmp;
- u32 noff;
- int err;
-
- if (!prev_num_progs) {
- old = NULL;
- noff = 0;
- } else {
- old = d->image + d->image_off;
+ void *new, *tmp;
+ u32 noff = 0;
+
+ if (prev_num_progs)
noff = d->image_off ^ (PAGE_SIZE / 2);
- }
new = d->num_progs ? d->image + noff : NULL;
tmp = d->num_progs ? d->rw_image + noff : NULL;
@@ -128,11 +123,10 @@ static void bpf_dispatcher_update(struct bpf_dispatcher *d, int prev_num_progs)
return;
}
- err = bpf_arch_text_poke(d->func, BPF_MOD_JUMP, old, new);
- if (err || !new)
- return;
+ __BPF_DISPATCHER_UPDATE(d, new ?: (void *)&bpf_dispatcher_nop_func);
- d->image_off = noff;
+ if (new)
+ d->image_off = noff;
}
void bpf_dispatcher_change_prog(struct bpf_dispatcher *d, struct bpf_prog *from,
diff --git a/kernel/bpf/memalloc.c b/kernel/bpf/memalloc.c
index 5f83be1d2018..4901fa1048cd 100644
--- a/kernel/bpf/memalloc.c
+++ b/kernel/bpf/memalloc.c
@@ -418,14 +418,17 @@ static void drain_mem_cache(struct bpf_mem_cache *c)
/* No progs are using this bpf_mem_cache, but htab_map_free() called
* bpf_mem_cache_free() for all remaining elements and they can be in
* free_by_rcu or in waiting_for_gp lists, so drain those lists now.
+ *
+ * Except for waiting_for_gp list, there are no concurrent operations
+ * on these lists, so it is safe to use __llist_del_all().
*/
llist_for_each_safe(llnode, t, __llist_del_all(&c->free_by_rcu))
free_one(c, llnode);
llist_for_each_safe(llnode, t, llist_del_all(&c->waiting_for_gp))
free_one(c, llnode);
- llist_for_each_safe(llnode, t, llist_del_all(&c->free_llist))
+ llist_for_each_safe(llnode, t, __llist_del_all(&c->free_llist))
free_one(c, llnode);
- llist_for_each_safe(llnode, t, llist_del_all(&c->free_llist_extra))
+ llist_for_each_safe(llnode, t, __llist_del_all(&c->free_llist_extra))
free_one(c, llnode);
}
@@ -493,6 +496,16 @@ void bpf_mem_alloc_destroy(struct bpf_mem_alloc *ma)
rcu_in_progress = 0;
for_each_possible_cpu(cpu) {
c = per_cpu_ptr(ma->cache, cpu);
+ /*
+ * refill_work may be unfinished for PREEMPT_RT kernel
+ * in which irq work is invoked in a per-CPU RT thread.
+ * It is also possible for kernel with
+ * arch_irq_work_has_interrupt() being false and irq
+ * work is invoked in timer interrupt. So waiting for
+ * the completion of irq work to ease the handling of
+ * concurrency.
+ */
+ irq_work_sync(&c->refill_work);
drain_mem_cache(c);
rcu_in_progress += atomic_read(&c->call_rcu_in_progress);
}
@@ -507,6 +520,7 @@ void bpf_mem_alloc_destroy(struct bpf_mem_alloc *ma)
cc = per_cpu_ptr(ma->caches, cpu);
for (i = 0; i < NUM_CACHES; i++) {
c = &cc->cache[i];
+ irq_work_sync(&c->refill_work);
drain_mem_cache(c);
rcu_in_progress += atomic_read(&c->call_rcu_in_progress);
}
diff --git a/kernel/bpf/percpu_freelist.c b/kernel/bpf/percpu_freelist.c
index b6e7f5c5b9ab..034cf87b54e9 100644
--- a/kernel/bpf/percpu_freelist.c
+++ b/kernel/bpf/percpu_freelist.c
@@ -100,22 +100,21 @@ void pcpu_freelist_populate(struct pcpu_freelist *s, void *buf, u32 elem_size,
u32 nr_elems)
{
struct pcpu_freelist_head *head;
- int i, cpu, pcpu_entries;
+ unsigned int cpu, cpu_idx, i, j, n, m;
- pcpu_entries = nr_elems / num_possible_cpus() + 1;
- i = 0;
+ n = nr_elems / num_possible_cpus();
+ m = nr_elems % num_possible_cpus();
+ cpu_idx = 0;
for_each_possible_cpu(cpu) {
-again:
head = per_cpu_ptr(s->freelist, cpu);
- /* No locking required as this is not visible yet. */
- pcpu_freelist_push_node(head, buf);
- i++;
- buf += elem_size;
- if (i == nr_elems)
- break;
- if (i % pcpu_entries)
- goto again;
+ j = n + (cpu_idx < m ? 1 : 0);
+ for (i = 0; i < j; i++) {
+ /* No locking required as this is not visible yet. */
+ pcpu_freelist_push_node(head, buf);
+ buf += elem_size;
+ }
+ cpu_idx++;
}
}
diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
index 014ee0953dbd..264b3dc714cc 100644
--- a/kernel/bpf/verifier.c
+++ b/kernel/bpf/verifier.c
@@ -1027,12 +1027,17 @@ out:
*/
static void *realloc_array(void *arr, size_t old_n, size_t new_n, size_t size)
{
+ void *new_arr;
+
if (!new_n || old_n == new_n)
goto out;
- arr = krealloc_array(arr, new_n, size, GFP_KERNEL);
- if (!arr)
+ new_arr = krealloc_array(arr, new_n, size, GFP_KERNEL);
+ if (!new_arr) {
+ kfree(arr);
return NULL;
+ }
+ arr = new_arr;
if (new_n > old_n)
memset(arr + old_n * size, 0, (new_n - old_n) * size);
@@ -6618,8 +6623,12 @@ static int release_reference(struct bpf_verifier_env *env,
return err;
bpf_for_each_reg_in_vstate(env->cur_state, state, reg, ({
- if (reg->ref_obj_id == ref_obj_id)
- __mark_reg_unknown(env, reg);
+ if (reg->ref_obj_id == ref_obj_id) {
+ if (!env->allow_ptr_leaks)
+ __mark_reg_not_init(env, reg);
+ else
+ __mark_reg_unknown(env, reg);
+ }
}));
return 0;
@@ -6736,11 +6745,11 @@ static int __check_func_call(struct bpf_verifier_env *env, struct bpf_insn *insn
/* Transfer references to the callee */
err = copy_reference_state(callee, caller);
if (err)
- return err;
+ goto err_out;
err = set_callee_state_cb(env, caller, callee, *insn_idx);
if (err)
- return err;
+ goto err_out;
clear_caller_saved_regs(env, caller->regs);
@@ -6757,6 +6766,11 @@ static int __check_func_call(struct bpf_verifier_env *env, struct bpf_insn *insn
print_verifier_state(env, callee, true);
}
return 0;
+
+err_out:
+ free_func_state(callee);
+ state->frame[state->curframe + 1] = NULL;
+ return err;
}
int map_set_for_each_callback_args(struct bpf_verifier_env *env,
@@ -6946,6 +6960,7 @@ static int set_user_ringbuf_callback_state(struct bpf_verifier_env *env,
__mark_reg_not_init(env, &callee->regs[BPF_REG_5]);
callee->in_callback_fn = true;
+ callee->callback_ret_range = tnum_range(0, 1);
return 0;
}
@@ -6969,8 +6984,7 @@ static int prepare_func_exit(struct bpf_verifier_env *env, int *insn_idx)
return -EINVAL;
}
- state->curframe--;
- caller = state->frame[state->curframe];
+ caller = state->frame[state->curframe - 1];
if (callee->in_callback_fn) {
/* enforce R0 return value range [0, 1]. */
struct tnum range = callee->callback_ret_range;
@@ -7009,7 +7023,7 @@ static int prepare_func_exit(struct bpf_verifier_env *env, int *insn_idx)
}
/* clear everything in the callee */
free_func_state(callee);
- state->frame[state->curframe + 1] = NULL;
+ state->frame[state->curframe--] = NULL;
return 0;
}
diff --git a/kernel/cgroup/cgroup-internal.h b/kernel/cgroup/cgroup-internal.h
index fd4020835ec6..367b0a42ada9 100644
--- a/kernel/cgroup/cgroup-internal.h
+++ b/kernel/cgroup/cgroup-internal.h
@@ -167,7 +167,6 @@ struct cgroup_mgctx {
extern spinlock_t css_set_lock;
extern struct cgroup_subsys *cgroup_subsys[];
extern struct list_head cgroup_roots;
-extern struct file_system_type cgroup_fs_type;
/* iterate across the hierarchies */
#define for_each_root(root) \
diff --git a/kernel/cgroup/cgroup.c b/kernel/cgroup/cgroup.c
index 7f486677ab1f..2319946715e0 100644
--- a/kernel/cgroup/cgroup.c
+++ b/kernel/cgroup/cgroup.c
@@ -1392,6 +1392,9 @@ static void cgroup_destroy_root(struct cgroup_root *root)
cgroup_free_root(root);
}
+/*
+ * Returned cgroup is without refcount but it's valid as long as cset pins it.
+ */
static inline struct cgroup *__cset_cgroup_from_root(struct css_set *cset,
struct cgroup_root *root)
{
@@ -1403,6 +1406,7 @@ static inline struct cgroup *__cset_cgroup_from_root(struct css_set *cset,
res_cgroup = cset->dfl_cgrp;
} else {
struct cgrp_cset_link *link;
+ lockdep_assert_held(&css_set_lock);
list_for_each_entry(link, &cset->cgrp_links, cgrp_link) {
struct cgroup *c = link->cgrp;
@@ -1414,6 +1418,7 @@ static inline struct cgroup *__cset_cgroup_from_root(struct css_set *cset,
}
}
+ BUG_ON(!res_cgroup);
return res_cgroup;
}
@@ -1436,23 +1441,36 @@ current_cgns_cgroup_from_root(struct cgroup_root *root)
rcu_read_unlock();
- BUG_ON(!res);
return res;
}
+/*
+ * Look up cgroup associated with current task's cgroup namespace on the default
+ * hierarchy.
+ *
+ * Unlike current_cgns_cgroup_from_root(), this doesn't need locks:
+ * - Internal rcu_read_lock is unnecessary because we don't dereference any rcu
+ * pointers.
+ * - css_set_lock is not needed because we just read cset->dfl_cgrp.
+ * - As a bonus returned cgrp is pinned with the current because it cannot
+ * switch cgroup_ns asynchronously.
+ */
+static struct cgroup *current_cgns_cgroup_dfl(void)
+{
+ struct css_set *cset;
+
+ cset = current->nsproxy->cgroup_ns->root_cset;
+ return __cset_cgroup_from_root(cset, &cgrp_dfl_root);
+}
+
/* look up cgroup associated with given css_set on the specified hierarchy */
static struct cgroup *cset_cgroup_from_root(struct css_set *cset,
struct cgroup_root *root)
{
- struct cgroup *res = NULL;
-
lockdep_assert_held(&cgroup_mutex);
lockdep_assert_held(&css_set_lock);
- res = __cset_cgroup_from_root(cset, root);
-
- BUG_ON(!res);
- return res;
+ return __cset_cgroup_from_root(cset, root);
}
/*
@@ -6191,9 +6209,7 @@ struct cgroup *cgroup_get_from_id(u64 id)
if (!cgrp)
return ERR_PTR(-ENOENT);
- spin_lock_irq(&css_set_lock);
- root_cgrp = current_cgns_cgroup_from_root(&cgrp_dfl_root);
- spin_unlock_irq(&css_set_lock);
+ root_cgrp = current_cgns_cgroup_dfl();
if (!cgroup_is_descendant(cgrp, root_cgrp)) {
cgroup_put(cgrp);
return ERR_PTR(-ENOENT);
@@ -6294,16 +6310,42 @@ void cgroup_fork(struct task_struct *child)
INIT_LIST_HEAD(&child->cg_list);
}
-static struct cgroup *cgroup_get_from_file(struct file *f)
+/**
+ * cgroup_v1v2_get_from_file - get a cgroup pointer from a file pointer
+ * @f: file corresponding to cgroup_dir
+ *
+ * Find the cgroup from a file pointer associated with a cgroup directory.
+ * Returns a pointer to the cgroup on success. ERR_PTR is returned if the
+ * cgroup cannot be found.
+ */
+static struct cgroup *cgroup_v1v2_get_from_file(struct file *f)
{
struct cgroup_subsys_state *css;
- struct cgroup *cgrp;
css = css_tryget_online_from_dir(f->f_path.dentry, NULL);
if (IS_ERR(css))
return ERR_CAST(css);
- cgrp = css->cgroup;
+ return css->cgroup;
+}
+
+/**
+ * cgroup_get_from_file - same as cgroup_v1v2_get_from_file, but only supports
+ * cgroup2.
+ * @f: file corresponding to cgroup2_dir
+ */
+static struct cgroup *cgroup_get_from_file(struct file *f)
+{
+ struct cgroup *cgrp = cgroup_v1v2_get_from_file(f);
+
+ if (IS_ERR(cgrp))
+ return ERR_CAST(cgrp);
+
+ if (!cgroup_on_dfl(cgrp)) {
+ cgroup_put(cgrp);
+ return ERR_PTR(-EBADF);
+ }
+
return cgrp;
}
@@ -6772,10 +6814,8 @@ struct cgroup *cgroup_get_from_path(const char *path)
struct cgroup *cgrp = ERR_PTR(-ENOENT);
struct cgroup *root_cgrp;
- spin_lock_irq(&css_set_lock);
- root_cgrp = current_cgns_cgroup_from_root(&cgrp_dfl_root);
+ root_cgrp = current_cgns_cgroup_dfl();
kn = kernfs_walk_and_get(root_cgrp->kn, path);
- spin_unlock_irq(&css_set_lock);
if (!kn)
goto out;
@@ -6800,15 +6840,15 @@ out:
EXPORT_SYMBOL_GPL(cgroup_get_from_path);
/**
- * cgroup_get_from_fd - get a cgroup pointer from a fd
- * @fd: fd obtained by open(cgroup2_dir)
+ * cgroup_v1v2_get_from_fd - get a cgroup pointer from a fd
+ * @fd: fd obtained by open(cgroup_dir)
*
* Find the cgroup from a fd which should be obtained
* by opening a cgroup directory. Returns a pointer to the
* cgroup on success. ERR_PTR is returned if the cgroup
* cannot be found.
*/
-struct cgroup *cgroup_get_from_fd(int fd)
+struct cgroup *cgroup_v1v2_get_from_fd(int fd)
{
struct cgroup *cgrp;
struct file *f;
@@ -6817,10 +6857,29 @@ struct cgroup *cgroup_get_from_fd(int fd)
if (!f)
return ERR_PTR(-EBADF);
- cgrp = cgroup_get_from_file(f);
+ cgrp = cgroup_v1v2_get_from_file(f);
fput(f);
return cgrp;
}
+
+/**
+ * cgroup_get_from_fd - same as cgroup_v1v2_get_from_fd, but only supports
+ * cgroup2.
+ * @fd: fd obtained by open(cgroup2_dir)
+ */
+struct cgroup *cgroup_get_from_fd(int fd)
+{
+ struct cgroup *cgrp = cgroup_v1v2_get_from_fd(fd);
+
+ if (IS_ERR(cgrp))
+ return ERR_CAST(cgrp);
+
+ if (!cgroup_on_dfl(cgrp)) {
+ cgroup_put(cgrp);
+ return ERR_PTR(-EBADF);
+ }
+ return cgrp;
+}
EXPORT_SYMBOL_GPL(cgroup_get_from_fd);
static u64 power_of_ten(int power)
diff --git a/kernel/events/core.c b/kernel/events/core.c
index aefc1e08e015..7f04f995c975 100644
--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -54,6 +54,7 @@
#include <linux/highmem.h>
#include <linux/pgtable.h>
#include <linux/buildid.h>
+#include <linux/task_work.h>
#include "internal.h"
@@ -2276,11 +2277,27 @@ event_sched_out(struct perf_event *event,
event->pmu->del(event, 0);
event->oncpu = -1;
- if (READ_ONCE(event->pending_disable) >= 0) {
- WRITE_ONCE(event->pending_disable, -1);
+ if (event->pending_disable) {
+ event->pending_disable = 0;
perf_cgroup_event_disable(event, ctx);
state = PERF_EVENT_STATE_OFF;
}
+
+ if (event->pending_sigtrap) {
+ bool dec = true;
+
+ event->pending_sigtrap = 0;
+ if (state != PERF_EVENT_STATE_OFF &&
+ !event->pending_work) {
+ event->pending_work = 1;
+ dec = false;
+ WARN_ON_ONCE(!atomic_long_inc_not_zero(&event->refcount));
+ task_work_add(current, &event->pending_task, TWA_RESUME);
+ }
+ if (dec)
+ local_dec(&event->ctx->nr_pending);
+ }
+
perf_event_set_state(event, state);
if (!is_software_event(event))
@@ -2320,6 +2337,7 @@ group_sched_out(struct perf_event *group_event,
#define DETACH_GROUP 0x01UL
#define DETACH_CHILD 0x02UL
+#define DETACH_DEAD 0x04UL
/*
* Cross CPU call to remove a performance event
@@ -2340,12 +2358,20 @@ __perf_remove_from_context(struct perf_event *event,
update_cgrp_time_from_cpuctx(cpuctx, false);
}
+ /*
+ * Ensure event_sched_out() switches to OFF, at the very least
+ * this avoids raising perf_pending_task() at this time.
+ */
+ if (flags & DETACH_DEAD)
+ event->pending_disable = 1;
event_sched_out(event, cpuctx, ctx);
if (flags & DETACH_GROUP)
perf_group_detach(event);
if (flags & DETACH_CHILD)
perf_child_detach(event);
list_del_event(event, ctx);
+ if (flags & DETACH_DEAD)
+ event->state = PERF_EVENT_STATE_DEAD;
if (!ctx->nr_events && ctx->is_active) {
if (ctx == &cpuctx->ctx)
@@ -2432,7 +2458,7 @@ static void __perf_event_disable(struct perf_event *event,
* hold the top-level event's child_mutex, so any descendant that
* goes to exit will block in perf_event_exit_event().
*
- * When called from perf_pending_event it's OK because event->ctx
+ * When called from perf_pending_irq it's OK because event->ctx
* is the current context on this CPU and preemption is disabled,
* hence we can't get into perf_event_task_sched_out for this context.
*/
@@ -2471,9 +2497,8 @@ EXPORT_SYMBOL_GPL(perf_event_disable);
void perf_event_disable_inatomic(struct perf_event *event)
{
- WRITE_ONCE(event->pending_disable, smp_processor_id());
- /* can fail, see perf_pending_event_disable() */
- irq_work_queue(&event->pending);
+ event->pending_disable = 1;
+ irq_work_queue(&event->pending_irq);
}
#define MAX_INTERRUPTS (~0ULL)
@@ -3428,11 +3453,23 @@ static void perf_event_context_sched_out(struct task_struct *task, int ctxn,
raw_spin_lock_nested(&next_ctx->lock, SINGLE_DEPTH_NESTING);
if (context_equiv(ctx, next_ctx)) {
+ perf_pmu_disable(pmu);
+
+ /* PMIs are disabled; ctx->nr_pending is stable. */
+ if (local_read(&ctx->nr_pending) ||
+ local_read(&next_ctx->nr_pending)) {
+ /*
+ * Must not swap out ctx when there's pending
+ * events that rely on the ctx->task relation.
+ */
+ raw_spin_unlock(&next_ctx->lock);
+ rcu_read_unlock();
+ goto inside_switch;
+ }
+
WRITE_ONCE(ctx->task, next);
WRITE_ONCE(next_ctx->task, task);
- perf_pmu_disable(pmu);
-
if (cpuctx->sched_cb_usage && pmu->sched_task)
pmu->sched_task(ctx, false);
@@ -3473,6 +3510,7 @@ unlock:
raw_spin_lock(&ctx->lock);
perf_pmu_disable(pmu);
+inside_switch:
if (cpuctx->sched_cb_usage && pmu->sched_task)
pmu->sched_task(ctx, false);
task_ctx_sched_out(cpuctx, ctx, EVENT_ALL);
@@ -4939,7 +4977,7 @@ static void perf_addr_filters_splice(struct perf_event *event,
static void _free_event(struct perf_event *event)
{
- irq_work_sync(&event->pending);
+ irq_work_sync(&event->pending_irq);
unaccount_event(event);
@@ -5093,9 +5131,7 @@ int perf_event_release_kernel(struct perf_event *event)
ctx = perf_event_ctx_lock(event);
WARN_ON_ONCE(ctx->parent_ctx);
- perf_remove_from_context(event, DETACH_GROUP);
- raw_spin_lock_irq(&ctx->lock);
/*
* Mark this event as STATE_DEAD, there is no external reference to it
* anymore.
@@ -5107,8 +5143,7 @@ int perf_event_release_kernel(struct perf_event *event)
* Thus this guarantees that we will in fact observe and kill _ALL_
* child events.
*/
- event->state = PERF_EVENT_STATE_DEAD;
- raw_spin_unlock_irq(&ctx->lock);
+ perf_remove_from_context(event, DETACH_GROUP|DETACH_DEAD);
perf_event_ctx_unlock(event, ctx);
@@ -6439,7 +6474,8 @@ static void perf_sigtrap(struct perf_event *event)
return;
/*
- * perf_pending_event() can race with the task exiting.
+ * Both perf_pending_task() and perf_pending_irq() can race with the
+ * task exiting.
*/
if (current->flags & PF_EXITING)
return;
@@ -6448,23 +6484,33 @@ static void perf_sigtrap(struct perf_event *event)
event->attr.type, event->attr.sig_data);
}
-static void perf_pending_event_disable(struct perf_event *event)
+/*
+ * Deliver the pending work in-event-context or follow the context.
+ */
+static void __perf_pending_irq(struct perf_event *event)
{
- int cpu = READ_ONCE(event->pending_disable);
+ int cpu = READ_ONCE(event->oncpu);
+ /*
+ * If the event isn't running; we done. event_sched_out() will have
+ * taken care of things.
+ */
if (cpu < 0)
return;
+ /*
+ * Yay, we hit home and are in the context of the event.
+ */
if (cpu == smp_processor_id()) {
- WRITE_ONCE(event->pending_disable, -1);
-
- if (event->attr.sigtrap) {
+ if (event->pending_sigtrap) {
+ event->pending_sigtrap = 0;
perf_sigtrap(event);
- atomic_set_release(&event->event_limit, 1); /* rearm event */
- return;
+ local_dec(&event->ctx->nr_pending);
+ }
+ if (event->pending_disable) {
+ event->pending_disable = 0;
+ perf_event_disable_local(event);
}
-
- perf_event_disable_local(event);
return;
}
@@ -6484,33 +6530,62 @@ static void perf_pending_event_disable(struct perf_event *event)
* irq_work_queue(); // FAILS
*
* irq_work_run()
- * perf_pending_event()
+ * perf_pending_irq()
*
* But the event runs on CPU-B and wants disabling there.
*/
- irq_work_queue_on(&event->pending, cpu);
+ irq_work_queue_on(&event->pending_irq, cpu);
}
-static void perf_pending_event(struct irq_work *entry)
+static void perf_pending_irq(struct irq_work *entry)
{
- struct perf_event *event = container_of(entry, struct perf_event, pending);
+ struct perf_event *event = container_of(entry, struct perf_event, pending_irq);
int rctx;
- rctx = perf_swevent_get_recursion_context();
/*
* If we 'fail' here, that's OK, it means recursion is already disabled
* and we won't recurse 'further'.
*/
+ rctx = perf_swevent_get_recursion_context();
- perf_pending_event_disable(event);
-
+ /*
+ * The wakeup isn't bound to the context of the event -- it can happen
+ * irrespective of where the event is.
+ */
if (event->pending_wakeup) {
event->pending_wakeup = 0;
perf_event_wakeup(event);
}
+ __perf_pending_irq(event);
+
+ if (rctx >= 0)
+ perf_swevent_put_recursion_context(rctx);
+}
+
+static void perf_pending_task(struct callback_head *head)
+{
+ struct perf_event *event = container_of(head, struct perf_event, pending_task);
+ int rctx;
+
+ /*
+ * If we 'fail' here, that's OK, it means recursion is already disabled
+ * and we won't recurse 'further'.
+ */
+ preempt_disable_notrace();
+ rctx = perf_swevent_get_recursion_context();
+
+ if (event->pending_work) {
+ event->pending_work = 0;
+ perf_sigtrap(event);
+ local_dec(&event->ctx->nr_pending);
+ }
+
if (rctx >= 0)
perf_swevent_put_recursion_context(rctx);
+ preempt_enable_notrace();
+
+ put_event(event);
}
#ifdef CONFIG_GUEST_PERF_EVENTS
@@ -8964,7 +9039,7 @@ static void perf_event_bpf_emit_ksymbols(struct bpf_prog *prog,
PERF_RECORD_KSYMBOL_TYPE_BPF,
(u64)(unsigned long)subprog->bpf_func,
subprog->jited_len, unregister,
- prog->aux->ksym.name);
+ subprog->aux->ksym.name);
}
}
}
@@ -9207,13 +9282,26 @@ int perf_event_account_interrupt(struct perf_event *event)
return __perf_event_account_interrupt(event, 1);
}
+static inline bool sample_is_allowed(struct perf_event *event, struct pt_regs *regs)
+{
+ /*
+ * Due to interrupt latency (AKA "skid"), we may enter the
+ * kernel before taking an overflow, even if the PMU is only
+ * counting user events.
+ */
+ if (event->attr.exclude_kernel && !user_mode(regs))
+ return false;
+
+ return true;
+}
+
/*
* Generic event overflow handling, sampling.
*/
static int __perf_event_overflow(struct perf_event *event,
- int throttle, struct perf_sample_data *data,
- struct pt_regs *regs)
+ int throttle, struct perf_sample_data *data,
+ struct pt_regs *regs)
{
int events = atomic_read(&event->event_limit);
int ret = 0;
@@ -9236,24 +9324,59 @@ static int __perf_event_overflow(struct perf_event *event,
if (events && atomic_dec_and_test(&event->event_limit)) {
ret = 1;
event->pending_kill = POLL_HUP;
- event->pending_addr = data->addr;
-
perf_event_disable_inatomic(event);
}
+ if (event->attr.sigtrap) {
+ /*
+ * The desired behaviour of sigtrap vs invalid samples is a bit
+ * tricky; on the one hand, one should not loose the SIGTRAP if
+ * it is the first event, on the other hand, we should also not
+ * trigger the WARN or override the data address.
+ */
+ bool valid_sample = sample_is_allowed(event, regs);
+ unsigned int pending_id = 1;
+
+ if (regs)
+ pending_id = hash32_ptr((void *)instruction_pointer(regs)) ?: 1;
+ if (!event->pending_sigtrap) {
+ event->pending_sigtrap = pending_id;
+ local_inc(&event->ctx->nr_pending);
+ } else if (event->attr.exclude_kernel && valid_sample) {
+ /*
+ * Should not be able to return to user space without
+ * consuming pending_sigtrap; with exceptions:
+ *
+ * 1. Where !exclude_kernel, events can overflow again
+ * in the kernel without returning to user space.
+ *
+ * 2. Events that can overflow again before the IRQ-
+ * work without user space progress (e.g. hrtimer).
+ * To approximate progress (with false negatives),
+ * check 32-bit hash of the current IP.
+ */
+ WARN_ON_ONCE(event->pending_sigtrap != pending_id);
+ }
+
+ event->pending_addr = 0;
+ if (valid_sample && (data->sample_flags & PERF_SAMPLE_ADDR))
+ event->pending_addr = data->addr;
+ irq_work_queue(&event->pending_irq);
+ }
+
READ_ONCE(event->overflow_handler)(event, data, regs);
if (*perf_event_fasync(event) && event->pending_kill) {
event->pending_wakeup = 1;
- irq_work_queue(&event->pending);
+ irq_work_queue(&event->pending_irq);
}
return ret;
}
int perf_event_overflow(struct perf_event *event,
- struct perf_sample_data *data,
- struct pt_regs *regs)
+ struct perf_sample_data *data,
+ struct pt_regs *regs)
{
return __perf_event_overflow(event, 1, data, regs);
}
@@ -9768,6 +9891,7 @@ void perf_tp_event(u16 event_type, u64 count, void *record, int entry_size,
perf_sample_data_init(&data, 0, 0);
data.raw = &raw;
+ data.sample_flags |= PERF_SAMPLE_RAW;
perf_trace_buf_update(record, event_type);
@@ -11570,8 +11694,8 @@ perf_event_alloc(struct perf_event_attr *attr, int cpu,
init_waitqueue_head(&event->waitq);
- event->pending_disable = -1;
- init_irq_work(&event->pending, perf_pending_event);
+ init_irq_work(&event->pending_irq, perf_pending_irq);
+ init_task_work(&event->pending_task, perf_pending_task);
mutex_init(&event->mmap_mutex);
raw_spin_lock_init(&event->addr_filters.lock);
@@ -11593,9 +11717,6 @@ perf_event_alloc(struct perf_event_attr *attr, int cpu,
if (parent_event)
event->event_caps = parent_event->event_caps;
- if (event->attr.sigtrap)
- atomic_set(&event->event_limit, 1);
-
if (task) {
event->attach_state = PERF_ATTACH_TASK;
/*
diff --git a/kernel/events/hw_breakpoint_test.c b/kernel/events/hw_breakpoint_test.c
index 5ced822df788..c57610f52bb4 100644
--- a/kernel/events/hw_breakpoint_test.c
+++ b/kernel/events/hw_breakpoint_test.c
@@ -295,11 +295,11 @@ static int test_init(struct kunit *test)
{
/* Most test cases want 2 distinct CPUs. */
if (num_online_cpus() < 2)
- return -EINVAL;
+ kunit_skip(test, "not enough cpus");
/* Want the system to not use breakpoints elsewhere. */
if (hw_breakpoint_is_used())
- return -EBUSY;
+ kunit_skip(test, "hw breakpoint already in use");
return 0;
}
diff --git a/kernel/events/ring_buffer.c b/kernel/events/ring_buffer.c
index 726132039c38..273a0fe7910a 100644
--- a/kernel/events/ring_buffer.c
+++ b/kernel/events/ring_buffer.c
@@ -22,7 +22,7 @@ static void perf_output_wakeup(struct perf_output_handle *handle)
atomic_set(&handle->rb->poll, EPOLLIN);
handle->event->pending_wakeup = 1;
- irq_work_queue(&handle->event->pending);
+ irq_work_queue(&handle->event->pending_irq);
}
/*
diff --git a/kernel/fork.c b/kernel/fork.c
index 08969f5aa38d..cfb09ca1b1bc 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -535,6 +535,9 @@ void put_task_stack(struct task_struct *tsk)
void free_task(struct task_struct *tsk)
{
+#ifdef CONFIG_SECCOMP
+ WARN_ON_ONCE(tsk->seccomp.filter);
+#endif
release_user_cpus_ptr(tsk);
scs_release(tsk);
@@ -2043,15 +2046,6 @@ static __latent_entropy struct task_struct *copy_process(
return ERR_PTR(-EINVAL);
}
- /*
- * If the new process will be in a different time namespace
- * do not allow it to share VM or a thread group with the forking task.
- */
- if (clone_flags & (CLONE_THREAD | CLONE_VM)) {
- if (nsp->time_ns != nsp->time_ns_for_children)
- return ERR_PTR(-EINVAL);
- }
-
if (clone_flags & CLONE_PIDFD) {
/*
* - CLONE_DETACHED is blocked so that we can potentially
@@ -2406,12 +2400,6 @@ static __latent_entropy struct task_struct *copy_process(
spin_lock(&current->sighand->siglock);
- /*
- * Copy seccomp details explicitly here, in case they were changed
- * before holding sighand lock.
- */
- copy_seccomp(p);
-
rv_task_fork(p);
rseq_fork(p, clone_flags);
@@ -2428,6 +2416,14 @@ static __latent_entropy struct task_struct *copy_process(
goto bad_fork_cancel_cgroup;
}
+ /* No more failure paths after this point. */
+
+ /*
+ * Copy seccomp details explicitly here, in case they were changed
+ * before holding sighand lock.
+ */
+ copy_seccomp(p);
+
init_task_pid_links(p);
if (likely(p->pid)) {
ptrace_init_task(p, (clone_flags & CLONE_PTRACE) || trace);
diff --git a/kernel/gcov/clang.c b/kernel/gcov/clang.c
index cbb0bed958ab..7670a811a565 100644
--- a/kernel/gcov/clang.c
+++ b/kernel/gcov/clang.c
@@ -280,6 +280,8 @@ void gcov_info_add(struct gcov_info *dst, struct gcov_info *src)
for (i = 0; i < sfn_ptr->num_counters; i++)
dfn_ptr->counters[i] += sfn_ptr->counters[i];
+
+ sfn_ptr = list_next_entry(sfn_ptr, head);
}
}
diff --git a/kernel/gcov/gcc_4_7.c b/kernel/gcov/gcc_4_7.c
index 460c12b7dfea..7971e989e425 100644
--- a/kernel/gcov/gcc_4_7.c
+++ b/kernel/gcov/gcc_4_7.c
@@ -30,6 +30,13 @@
#define GCOV_TAG_FUNCTION_LENGTH 3
+/* Since GCC 12.1 sizes are in BYTES and not in WORDS (4B). */
+#if (__GNUC__ >= 12)
+#define GCOV_UNIT_SIZE 4
+#else
+#define GCOV_UNIT_SIZE 1
+#endif
+
static struct gcov_info *gcov_info_head;
/**
@@ -383,12 +390,18 @@ size_t convert_to_gcda(char *buffer, struct gcov_info *info)
pos += store_gcov_u32(buffer, pos, info->version);
pos += store_gcov_u32(buffer, pos, info->stamp);
+#if (__GNUC__ >= 12)
+ /* Use zero as checksum of the compilation unit. */
+ pos += store_gcov_u32(buffer, pos, 0);
+#endif
+
for (fi_idx = 0; fi_idx < info->n_functions; fi_idx++) {
fi_ptr = info->functions[fi_idx];
/* Function record. */
pos += store_gcov_u32(buffer, pos, GCOV_TAG_FUNCTION);
- pos += store_gcov_u32(buffer, pos, GCOV_TAG_FUNCTION_LENGTH);
+ pos += store_gcov_u32(buffer, pos,
+ GCOV_TAG_FUNCTION_LENGTH * GCOV_UNIT_SIZE);
pos += store_gcov_u32(buffer, pos, fi_ptr->ident);
pos += store_gcov_u32(buffer, pos, fi_ptr->lineno_checksum);
pos += store_gcov_u32(buffer, pos, fi_ptr->cfg_checksum);
@@ -402,7 +415,8 @@ size_t convert_to_gcda(char *buffer, struct gcov_info *info)
/* Counter record. */
pos += store_gcov_u32(buffer, pos,
GCOV_TAG_FOR_COUNTER(ct_idx));
- pos += store_gcov_u32(buffer, pos, ci_ptr->num * 2);
+ pos += store_gcov_u32(buffer, pos,
+ ci_ptr->num * 2 * GCOV_UNIT_SIZE);
for (cv_idx = 0; cv_idx < ci_ptr->num; cv_idx++) {
pos += store_gcov_u64(buffer, pos,
diff --git a/kernel/kcsan/core.c b/kernel/kcsan/core.c
index fe12dfe254ec..54d077e1a2dc 100644
--- a/kernel/kcsan/core.c
+++ b/kernel/kcsan/core.c
@@ -14,10 +14,12 @@
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/list.h>
+#include <linux/minmax.h>
#include <linux/moduleparam.h>
#include <linux/percpu.h>
#include <linux/preempt.h>
#include <linux/sched.h>
+#include <linux/string.h>
#include <linux/uaccess.h>
#include "encoding.h"
@@ -1308,3 +1310,51 @@ noinline void __tsan_atomic_signal_fence(int memorder)
}
}
EXPORT_SYMBOL(__tsan_atomic_signal_fence);
+
+#ifdef __HAVE_ARCH_MEMSET
+void *__tsan_memset(void *s, int c, size_t count);
+noinline void *__tsan_memset(void *s, int c, size_t count)
+{
+ /*
+ * Instead of not setting up watchpoints where accessed size is greater
+ * than MAX_ENCODABLE_SIZE, truncate checked size to MAX_ENCODABLE_SIZE.
+ */
+ size_t check_len = min_t(size_t, count, MAX_ENCODABLE_SIZE);
+
+ check_access(s, check_len, KCSAN_ACCESS_WRITE, _RET_IP_);
+ return memset(s, c, count);
+}
+#else
+void *__tsan_memset(void *s, int c, size_t count) __alias(memset);
+#endif
+EXPORT_SYMBOL(__tsan_memset);
+
+#ifdef __HAVE_ARCH_MEMMOVE
+void *__tsan_memmove(void *dst, const void *src, size_t len);
+noinline void *__tsan_memmove(void *dst, const void *src, size_t len)
+{
+ size_t check_len = min_t(size_t, len, MAX_ENCODABLE_SIZE);
+
+ check_access(dst, check_len, KCSAN_ACCESS_WRITE, _RET_IP_);
+ check_access(src, check_len, 0, _RET_IP_);
+ return memmove(dst, src, len);
+}
+#else
+void *__tsan_memmove(void *dst, const void *src, size_t len) __alias(memmove);
+#endif
+EXPORT_SYMBOL(__tsan_memmove);
+
+#ifdef __HAVE_ARCH_MEMCPY
+void *__tsan_memcpy(void *dst, const void *src, size_t len);
+noinline void *__tsan_memcpy(void *dst, const void *src, size_t len)
+{
+ size_t check_len = min_t(size_t, len, MAX_ENCODABLE_SIZE);
+
+ check_access(dst, check_len, KCSAN_ACCESS_WRITE, _RET_IP_);
+ check_access(src, check_len, 0, _RET_IP_);
+ return memcpy(dst, src, len);
+}
+#else
+void *__tsan_memcpy(void *dst, const void *src, size_t len) __alias(memcpy);
+#endif
+EXPORT_SYMBOL(__tsan_memcpy);
diff --git a/kernel/kprobes.c b/kernel/kprobes.c
index 3220b0a2fb4a..3050631e528d 100644
--- a/kernel/kprobes.c
+++ b/kernel/kprobes.c
@@ -1766,7 +1766,13 @@ static int __unregister_kprobe_top(struct kprobe *p)
if ((list_p != p) && (list_p->post_handler))
goto noclean;
}
- ap->post_handler = NULL;
+ /*
+ * For the kprobe-on-ftrace case, we keep the
+ * post_handler setting to identify this aggrprobe
+ * armed with kprobe_ipmodify_ops.
+ */
+ if (!kprobe_ftrace(ap))
+ ap->post_handler = NULL;
}
noclean:
/*
@@ -2429,8 +2435,11 @@ int enable_kprobe(struct kprobe *kp)
if (!kprobes_all_disarmed && kprobe_disabled(p)) {
p->flags &= ~KPROBE_FLAG_DISABLED;
ret = arm_kprobe(p);
- if (ret)
+ if (ret) {
p->flags |= KPROBE_FLAG_DISABLED;
+ if (p != kp)
+ kp->flags |= KPROBE_FLAG_DISABLED;
+ }
}
out:
mutex_unlock(&kprobe_mutex);
diff --git a/kernel/nsproxy.c b/kernel/nsproxy.c
index eec72ca962e2..a487ff24129b 100644
--- a/kernel/nsproxy.c
+++ b/kernel/nsproxy.c
@@ -157,7 +157,8 @@ int copy_namespaces(unsigned long flags, struct task_struct *tsk)
if (likely(!(flags & (CLONE_NEWNS | CLONE_NEWUTS | CLONE_NEWIPC |
CLONE_NEWPID | CLONE_NEWNET |
CLONE_NEWCGROUP | CLONE_NEWTIME)))) {
- if (likely(old_ns->time_ns_for_children == old_ns->time_ns)) {
+ if ((flags & CLONE_VM) ||
+ likely(old_ns->time_ns_for_children == old_ns->time_ns)) {
get_nsproxy(old_ns);
return 0;
}
@@ -179,7 +180,8 @@ int copy_namespaces(unsigned long flags, struct task_struct *tsk)
if (IS_ERR(new_ns))
return PTR_ERR(new_ns);
- timens_on_fork(new_ns, tsk);
+ if ((flags & CLONE_VM) == 0)
+ timens_on_fork(new_ns, tsk);
tsk->nsproxy = new_ns;
return 0;
@@ -254,6 +256,23 @@ void exit_task_namespaces(struct task_struct *p)
switch_task_namespaces(p, NULL);
}
+int exec_task_namespaces(void)
+{
+ struct task_struct *tsk = current;
+ struct nsproxy *new;
+
+ if (tsk->nsproxy->time_ns_for_children == tsk->nsproxy->time_ns)
+ return 0;
+
+ new = create_new_namespaces(0, tsk, current_user_ns(), tsk->fs);
+ if (IS_ERR(new))
+ return PTR_ERR(new);
+
+ timens_on_fork(new, tsk);
+ switch_task_namespaces(tsk, new);
+ return 0;
+}
+
static int check_setns_flags(unsigned long flags)
{
if (!flags || (flags & ~(CLONE_NEWNS | CLONE_NEWUTS | CLONE_NEWIPC |
diff --git a/kernel/power/hibernate.c b/kernel/power/hibernate.c
index f58a0aa92310..793c55a2becb 100644
--- a/kernel/power/hibernate.c
+++ b/kernel/power/hibernate.c
@@ -645,7 +645,7 @@ static void power_down(void)
int error;
if (hibernation_mode == HIBERNATION_SUSPEND) {
- error = suspend_devices_and_enter(PM_SUSPEND_MEM);
+ error = suspend_devices_and_enter(mem_sleep_current);
if (error) {
hibernation_mode = hibernation_ops ?
HIBERNATION_PLATFORM :
diff --git a/kernel/printk/printk.c b/kernel/printk/printk.c
index 39221b0f918d..a5ed2e53547c 100644
--- a/kernel/printk/printk.c
+++ b/kernel/printk/printk.c
@@ -2482,7 +2482,7 @@ static int __add_preferred_console(char *name, int idx, char *options,
return -E2BIG;
if (!brl_options)
preferred_console = i;
- strlcpy(c->name, name, sizeof(c->name));
+ strscpy(c->name, name, sizeof(c->name));
c->options = options;
set_user_specified(c, user_specified);
braille_set_options(c, brl_options);
diff --git a/kernel/printk/printk_ringbuffer.c b/kernel/printk/printk_ringbuffer.c
index 2b7b6ddab4f7..2dc4d5a1f1ff 100644
--- a/kernel/printk/printk_ringbuffer.c
+++ b/kernel/printk/printk_ringbuffer.c
@@ -203,7 +203,7 @@
* prb_rec_init_wr(&r, 5);
*
* // try to extend, but only if it does not exceed 32 bytes
- * if (prb_reserve_in_last(&e, &test_rb, &r, printk_caller_id()), 32) {
+ * if (prb_reserve_in_last(&e, &test_rb, &r, printk_caller_id(), 32)) {
* snprintf(&r.text_buf[r.info->text_len],
* r.text_buf_size - r.info->text_len, "hello");
*
diff --git a/kernel/rcu/Kconfig b/kernel/rcu/Kconfig
index 1b0d79b2f5fa..ab62074174c3 100644
--- a/kernel/rcu/Kconfig
+++ b/kernel/rcu/Kconfig
@@ -309,4 +309,12 @@ config TASKS_TRACE_RCU_READ_MB
Say N here if you hate read-side memory barriers.
Take the default if you are unsure.
+config RCU_LAZY
+ bool "RCU callback lazy invocation functionality"
+ depends on RCU_NOCB_CPU
+ default n
+ help
+ To save power, batch RCU callbacks and flush after delay, memory
+ pressure, or callback list growing too big.
+
endmenu # "RCU Subsystem"
diff --git a/kernel/rcu/rcu.h b/kernel/rcu/rcu.h
index 1f7ca484483a..c5aa934de59b 100644
--- a/kernel/rcu/rcu.h
+++ b/kernel/rcu/rcu.h
@@ -478,6 +478,14 @@ enum rcutorture_type {
INVALID_RCU_FLAVOR
};
+#if defined(CONFIG_RCU_LAZY)
+unsigned long rcu_lazy_get_jiffies_till_flush(void);
+void rcu_lazy_set_jiffies_till_flush(unsigned long j);
+#else
+static inline unsigned long rcu_lazy_get_jiffies_till_flush(void) { return 0; }
+static inline void rcu_lazy_set_jiffies_till_flush(unsigned long j) { }
+#endif
+
#if defined(CONFIG_TREE_RCU)
void rcutorture_get_gp_data(enum rcutorture_type test_type, int *flags,
unsigned long *gp_seq);
diff --git a/kernel/rcu/rcuscale.c b/kernel/rcu/rcuscale.c
index 3ef02d4a8108..91fb5905a008 100644
--- a/kernel/rcu/rcuscale.c
+++ b/kernel/rcu/rcuscale.c
@@ -95,6 +95,7 @@ torture_param(int, verbose, 1, "Enable verbose debugging printk()s");
torture_param(int, writer_holdoff, 0, "Holdoff (us) between GPs, zero to disable");
torture_param(int, kfree_rcu_test, 0, "Do we run a kfree_rcu() scale test?");
torture_param(int, kfree_mult, 1, "Multiple of kfree_obj size to allocate.");
+torture_param(int, kfree_by_call_rcu, 0, "Use call_rcu() to emulate kfree_rcu()?");
static char *scale_type = "rcu";
module_param(scale_type, charp, 0444);
@@ -175,7 +176,7 @@ static struct rcu_scale_ops rcu_ops = {
.get_gp_seq = rcu_get_gp_seq,
.gp_diff = rcu_seq_diff,
.exp_completed = rcu_exp_batches_completed,
- .async = call_rcu,
+ .async = call_rcu_hurry,
.gp_barrier = rcu_barrier,
.sync = synchronize_rcu,
.exp_sync = synchronize_rcu_expedited,
@@ -659,6 +660,14 @@ struct kfree_obj {
struct rcu_head rh;
};
+/* Used if doing RCU-kfree'ing via call_rcu(). */
+static void kfree_call_rcu(struct rcu_head *rh)
+{
+ struct kfree_obj *obj = container_of(rh, struct kfree_obj, rh);
+
+ kfree(obj);
+}
+
static int
kfree_scale_thread(void *arg)
{
@@ -696,6 +705,11 @@ kfree_scale_thread(void *arg)
if (!alloc_ptr)
return -ENOMEM;
+ if (kfree_by_call_rcu) {
+ call_rcu(&(alloc_ptr->rh), kfree_call_rcu);
+ continue;
+ }
+
// By default kfree_rcu_test_single and kfree_rcu_test_double are
// initialized to false. If both have the same value (false or true)
// both are randomly tested, otherwise only the one with value true
@@ -767,11 +781,58 @@ kfree_scale_shutdown(void *arg)
return -EINVAL;
}
+// Used if doing RCU-kfree'ing via call_rcu().
+static unsigned long jiffies_at_lazy_cb;
+static struct rcu_head lazy_test1_rh;
+static int rcu_lazy_test1_cb_called;
+static void call_rcu_lazy_test1(struct rcu_head *rh)
+{
+ jiffies_at_lazy_cb = jiffies;
+ WRITE_ONCE(rcu_lazy_test1_cb_called, 1);
+}
+
static int __init
kfree_scale_init(void)
{
- long i;
int firsterr = 0;
+ long i;
+ unsigned long jif_start;
+ unsigned long orig_jif;
+
+ // Also, do a quick self-test to ensure laziness is as much as
+ // expected.
+ if (kfree_by_call_rcu && !IS_ENABLED(CONFIG_RCU_LAZY)) {
+ pr_alert("CONFIG_RCU_LAZY is disabled, falling back to kfree_rcu() for delayed RCU kfree'ing\n");
+ kfree_by_call_rcu = 0;
+ }
+
+ if (kfree_by_call_rcu) {
+ /* do a test to check the timeout. */
+ orig_jif = rcu_lazy_get_jiffies_till_flush();
+
+ rcu_lazy_set_jiffies_till_flush(2 * HZ);
+ rcu_barrier();
+
+ jif_start = jiffies;
+ jiffies_at_lazy_cb = 0;
+ call_rcu(&lazy_test1_rh, call_rcu_lazy_test1);
+
+ smp_cond_load_relaxed(&rcu_lazy_test1_cb_called, VAL == 1);
+
+ rcu_lazy_set_jiffies_till_flush(orig_jif);
+
+ if (WARN_ON_ONCE(jiffies_at_lazy_cb - jif_start < 2 * HZ)) {
+ pr_alert("ERROR: call_rcu() CBs are not being lazy as expected!\n");
+ WARN_ON_ONCE(1);
+ return -1;
+ }
+
+ if (WARN_ON_ONCE(jiffies_at_lazy_cb - jif_start > 3 * HZ)) {
+ pr_alert("ERROR: call_rcu() CBs are being too lazy!\n");
+ WARN_ON_ONCE(1);
+ return -1;
+ }
+ }
kfree_nrealthreads = compute_real(kfree_nthreads);
/* Start up the kthreads. */
@@ -784,7 +845,9 @@ kfree_scale_init(void)
schedule_timeout_uninterruptible(1);
}
- pr_alert("kfree object size=%zu\n", kfree_mult * sizeof(struct kfree_obj));
+ pr_alert("kfree object size=%zu, kfree_by_call_rcu=%d\n",
+ kfree_mult * sizeof(struct kfree_obj),
+ kfree_by_call_rcu);
kfree_reader_tasks = kcalloc(kfree_nrealthreads, sizeof(kfree_reader_tasks[0]),
GFP_KERNEL);
diff --git a/kernel/rcu/rcutorture.c b/kernel/rcu/rcutorture.c
index b4c74ce10225..634df26a2c27 100644
--- a/kernel/rcu/rcutorture.c
+++ b/kernel/rcu/rcutorture.c
@@ -357,6 +357,10 @@ struct rcu_torture_ops {
bool (*poll_gp_state_exp)(unsigned long oldstate);
void (*cond_sync_exp)(unsigned long oldstate);
void (*cond_sync_exp_full)(struct rcu_gp_oldstate *rgosp);
+ unsigned long (*get_comp_state)(void);
+ void (*get_comp_state_full)(struct rcu_gp_oldstate *rgosp);
+ bool (*same_gp_state)(unsigned long oldstate1, unsigned long oldstate2);
+ bool (*same_gp_state_full)(struct rcu_gp_oldstate *rgosp1, struct rcu_gp_oldstate *rgosp2);
unsigned long (*get_gp_state)(void);
void (*get_gp_state_full)(struct rcu_gp_oldstate *rgosp);
unsigned long (*get_gp_completed)(void);
@@ -510,7 +514,7 @@ static unsigned long rcu_no_completed(void)
static void rcu_torture_deferred_free(struct rcu_torture *p)
{
- call_rcu(&p->rtort_rcu, rcu_torture_cb);
+ call_rcu_hurry(&p->rtort_rcu, rcu_torture_cb);
}
static void rcu_sync_torture_init(void)
@@ -535,6 +539,10 @@ static struct rcu_torture_ops rcu_ops = {
.deferred_free = rcu_torture_deferred_free,
.sync = synchronize_rcu,
.exp_sync = synchronize_rcu_expedited,
+ .same_gp_state = same_state_synchronize_rcu,
+ .same_gp_state_full = same_state_synchronize_rcu_full,
+ .get_comp_state = get_completed_synchronize_rcu,
+ .get_comp_state_full = get_completed_synchronize_rcu_full,
.get_gp_state = get_state_synchronize_rcu,
.get_gp_state_full = get_state_synchronize_rcu_full,
.get_gp_completed = get_completed_synchronize_rcu,
@@ -551,7 +559,7 @@ static struct rcu_torture_ops rcu_ops = {
.start_gp_poll_exp_full = start_poll_synchronize_rcu_expedited_full,
.poll_gp_state_exp = poll_state_synchronize_rcu,
.cond_sync_exp = cond_synchronize_rcu_expedited,
- .call = call_rcu,
+ .call = call_rcu_hurry,
.cb_barrier = rcu_barrier,
.fqs = rcu_force_quiescent_state,
.stats = NULL,
@@ -855,7 +863,7 @@ static void rcu_tasks_torture_deferred_free(struct rcu_torture *p)
static void synchronize_rcu_mult_test(void)
{
- synchronize_rcu_mult(call_rcu_tasks, call_rcu);
+ synchronize_rcu_mult(call_rcu_tasks, call_rcu_hurry);
}
static struct rcu_torture_ops tasks_ops = {
@@ -1265,13 +1273,15 @@ static void rcu_torture_write_types(void)
} else if (gp_normal && !cur_ops->deferred_free) {
pr_alert("%s: gp_normal without primitives.\n", __func__);
}
- if (gp_poll1 && cur_ops->start_gp_poll && cur_ops->poll_gp_state) {
+ if (gp_poll1 && cur_ops->get_comp_state && cur_ops->same_gp_state &&
+ cur_ops->start_gp_poll && cur_ops->poll_gp_state) {
synctype[nsynctypes++] = RTWS_POLL_GET;
pr_info("%s: Testing polling GPs.\n", __func__);
} else if (gp_poll && (!cur_ops->start_gp_poll || !cur_ops->poll_gp_state)) {
pr_alert("%s: gp_poll without primitives.\n", __func__);
}
- if (gp_poll_full1 && cur_ops->start_gp_poll_full && cur_ops->poll_gp_state_full) {
+ if (gp_poll_full1 && cur_ops->get_comp_state_full && cur_ops->same_gp_state_full
+ && cur_ops->start_gp_poll_full && cur_ops->poll_gp_state_full) {
synctype[nsynctypes++] = RTWS_POLL_GET_FULL;
pr_info("%s: Testing polling full-state GPs.\n", __func__);
} else if (gp_poll_full && (!cur_ops->start_gp_poll_full || !cur_ops->poll_gp_state_full)) {
@@ -1346,14 +1356,18 @@ rcu_torture_writer(void *arg)
struct rcu_gp_oldstate cookie_full;
int expediting = 0;
unsigned long gp_snap;
+ unsigned long gp_snap1;
struct rcu_gp_oldstate gp_snap_full;
+ struct rcu_gp_oldstate gp_snap1_full;
int i;
int idx;
int oldnice = task_nice(current);
+ struct rcu_gp_oldstate rgo[NUM_ACTIVE_RCU_POLL_FULL_OLDSTATE];
struct rcu_torture *rp;
struct rcu_torture *old_rp;
static DEFINE_TORTURE_RANDOM(rand);
bool stutter_waited;
+ unsigned long ulo[NUM_ACTIVE_RCU_POLL_OLDSTATE];
VERBOSE_TOROUT_STRING("rcu_torture_writer task started");
if (!can_expedite)
@@ -1470,20 +1484,43 @@ rcu_torture_writer(void *arg)
break;
case RTWS_POLL_GET:
rcu_torture_writer_state = RTWS_POLL_GET;
+ for (i = 0; i < ARRAY_SIZE(ulo); i++)
+ ulo[i] = cur_ops->get_comp_state();
gp_snap = cur_ops->start_gp_poll();
rcu_torture_writer_state = RTWS_POLL_WAIT;
- while (!cur_ops->poll_gp_state(gp_snap))
+ while (!cur_ops->poll_gp_state(gp_snap)) {
+ gp_snap1 = cur_ops->get_gp_state();
+ for (i = 0; i < ARRAY_SIZE(ulo); i++)
+ if (cur_ops->poll_gp_state(ulo[i]) ||
+ cur_ops->same_gp_state(ulo[i], gp_snap1)) {
+ ulo[i] = gp_snap1;
+ break;
+ }
+ WARN_ON_ONCE(i >= ARRAY_SIZE(ulo));
torture_hrtimeout_jiffies(torture_random(&rand) % 16,
&rand);
+ }
rcu_torture_pipe_update(old_rp);
break;
case RTWS_POLL_GET_FULL:
rcu_torture_writer_state = RTWS_POLL_GET_FULL;
+ for (i = 0; i < ARRAY_SIZE(rgo); i++)
+ cur_ops->get_comp_state_full(&rgo[i]);
cur_ops->start_gp_poll_full(&gp_snap_full);
rcu_torture_writer_state = RTWS_POLL_WAIT_FULL;
- while (!cur_ops->poll_gp_state_full(&gp_snap_full))
+ while (!cur_ops->poll_gp_state_full(&gp_snap_full)) {
+ cur_ops->get_gp_state_full(&gp_snap1_full);
+ for (i = 0; i < ARRAY_SIZE(rgo); i++)
+ if (cur_ops->poll_gp_state_full(&rgo[i]) ||
+ cur_ops->same_gp_state_full(&rgo[i],
+ &gp_snap1_full)) {
+ rgo[i] = gp_snap1_full;
+ break;
+ }
+ WARN_ON_ONCE(i >= ARRAY_SIZE(rgo));
torture_hrtimeout_jiffies(torture_random(&rand) % 16,
&rand);
+ }
rcu_torture_pipe_update(old_rp);
break;
case RTWS_POLL_GET_EXP:
@@ -3395,13 +3432,13 @@ static void rcu_test_debug_objects(void)
/* Try to queue the rh2 pair of callbacks for the same grace period. */
preempt_disable(); /* Prevent preemption from interrupting test. */
rcu_read_lock(); /* Make it impossible to finish a grace period. */
- call_rcu(&rh1, rcu_torture_leak_cb); /* Start grace period. */
+ call_rcu_hurry(&rh1, rcu_torture_leak_cb); /* Start grace period. */
local_irq_disable(); /* Make it harder to start a new grace period. */
- call_rcu(&rh2, rcu_torture_leak_cb);
- call_rcu(&rh2, rcu_torture_err_cb); /* Duplicate callback. */
+ call_rcu_hurry(&rh2, rcu_torture_leak_cb);
+ call_rcu_hurry(&rh2, rcu_torture_err_cb); /* Duplicate callback. */
if (rhp) {
- call_rcu(rhp, rcu_torture_leak_cb);
- call_rcu(rhp, rcu_torture_err_cb); /* Another duplicate callback. */
+ call_rcu_hurry(rhp, rcu_torture_leak_cb);
+ call_rcu_hurry(rhp, rcu_torture_err_cb); /* Another duplicate callback. */
}
local_irq_enable();
rcu_read_unlock();
diff --git a/kernel/rcu/sync.c b/kernel/rcu/sync.c
index 5cefc702158f..e550f97779b8 100644
--- a/kernel/rcu/sync.c
+++ b/kernel/rcu/sync.c
@@ -44,7 +44,7 @@ static void rcu_sync_func(struct rcu_head *rhp);
static void rcu_sync_call(struct rcu_sync *rsp)
{
- call_rcu(&rsp->cb_head, rcu_sync_func);
+ call_rcu_hurry(&rsp->cb_head, rcu_sync_func);
}
/**
diff --git a/kernel/rcu/tasks.h b/kernel/rcu/tasks.h
index f5bf6fb430da..b0b885e071fa 100644
--- a/kernel/rcu/tasks.h
+++ b/kernel/rcu/tasks.h
@@ -728,7 +728,7 @@ static void rcu_tasks_wait_gp(struct rcu_tasks *rtp)
if (rtsi > 0 && !reported && time_after(j, lastinfo + rtsi)) {
lastinfo = j;
rtsi = rtsi * rcu_task_stall_info_mult;
- pr_info("%s: %s grace period %lu is %lu jiffies old.\n",
+ pr_info("%s: %s grace period number %lu (since boot) is %lu jiffies old.\n",
__func__, rtp->kname, rtp->tasks_gp_seq, j - rtp->gp_start);
}
}
diff --git a/kernel/rcu/tiny.c b/kernel/rcu/tiny.c
index a33a8d4942c3..72913ce21258 100644
--- a/kernel/rcu/tiny.c
+++ b/kernel/rcu/tiny.c
@@ -44,7 +44,7 @@ static struct rcu_ctrlblk rcu_ctrlblk = {
void rcu_barrier(void)
{
- wait_rcu_gp(call_rcu);
+ wait_rcu_gp(call_rcu_hurry);
}
EXPORT_SYMBOL(rcu_barrier);
diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c
index 6bb8e72bc815..d04f2192f02c 100644
--- a/kernel/rcu/tree.c
+++ b/kernel/rcu/tree.c
@@ -301,12 +301,6 @@ static bool rcu_dynticks_in_eqs(int snap)
return !(snap & RCU_DYNTICKS_IDX);
}
-/* Return true if the specified CPU is currently idle from an RCU viewpoint. */
-bool rcu_is_idle_cpu(int cpu)
-{
- return rcu_dynticks_in_eqs(rcu_dynticks_snap(cpu));
-}
-
/*
* Return true if the CPU corresponding to the specified rcu_data
* structure has spent some time in an extended quiescent state since
@@ -1403,30 +1397,32 @@ static void rcu_poll_gp_seq_end(unsigned long *snap)
// where caller does not hold the root rcu_node structure's lock.
static void rcu_poll_gp_seq_start_unlocked(unsigned long *snap)
{
+ unsigned long flags;
struct rcu_node *rnp = rcu_get_root();
if (rcu_init_invoked()) {
lockdep_assert_irqs_enabled();
- raw_spin_lock_irq_rcu_node(rnp);
+ raw_spin_lock_irqsave_rcu_node(rnp, flags);
}
rcu_poll_gp_seq_start(snap);
if (rcu_init_invoked())
- raw_spin_unlock_irq_rcu_node(rnp);
+ raw_spin_unlock_irqrestore_rcu_node(rnp, flags);
}
// Make the polled API aware of the end of a grace period, but where
// caller does not hold the root rcu_node structure's lock.
static void rcu_poll_gp_seq_end_unlocked(unsigned long *snap)
{
+ unsigned long flags;
struct rcu_node *rnp = rcu_get_root();
if (rcu_init_invoked()) {
lockdep_assert_irqs_enabled();
- raw_spin_lock_irq_rcu_node(rnp);
+ raw_spin_lock_irqsave_rcu_node(rnp, flags);
}
rcu_poll_gp_seq_end(snap);
if (rcu_init_invoked())
- raw_spin_unlock_irq_rcu_node(rnp);
+ raw_spin_unlock_irqrestore_rcu_node(rnp, flags);
}
/*
@@ -2106,7 +2102,7 @@ int rcutree_dying_cpu(unsigned int cpu)
if (!IS_ENABLED(CONFIG_HOTPLUG_CPU))
return 0;
- blkd = !!(rnp->qsmask & rdp->grpmask);
+ blkd = !!(READ_ONCE(rnp->qsmask) & rdp->grpmask);
trace_rcu_grace_period(rcu_state.name, READ_ONCE(rnp->gp_seq),
blkd ? TPS("cpuofl-bgp") : TPS("cpuofl"));
return 0;
@@ -2416,7 +2412,7 @@ void rcu_force_quiescent_state(void)
struct rcu_node *rnp_old = NULL;
/* Funnel through hierarchy to reduce memory contention. */
- rnp = __this_cpu_read(rcu_data.mynode);
+ rnp = raw_cpu_read(rcu_data.mynode);
for (; rnp != NULL; rnp = rnp->parent) {
ret = (READ_ONCE(rcu_state.gp_flags) & RCU_GP_FLAG_FQS) ||
!raw_spin_trylock(&rnp->fqslock);
@@ -2728,47 +2724,8 @@ static void check_cb_ovld(struct rcu_data *rdp)
raw_spin_unlock_rcu_node(rnp);
}
-/**
- * call_rcu() - Queue an RCU callback for invocation after a grace period.
- * @head: structure to be used for queueing the RCU updates.
- * @func: actual callback function to be invoked after the grace period
- *
- * The callback function will be invoked some time after a full grace
- * period elapses, in other words after all pre-existing RCU read-side
- * critical sections have completed. However, the callback function
- * might well execute concurrently with RCU read-side critical sections
- * that started after call_rcu() was invoked.
- *
- * RCU read-side critical sections are delimited by rcu_read_lock()
- * and rcu_read_unlock(), and may be nested. In addition, but only in
- * v5.0 and later, regions of code across which interrupts, preemption,
- * or softirqs have been disabled also serve as RCU read-side critical
- * sections. This includes hardware interrupt handlers, softirq handlers,
- * and NMI handlers.
- *
- * Note that all CPUs must agree that the grace period extended beyond
- * all pre-existing RCU read-side critical section. On systems with more
- * than one CPU, this means that when "func()" is invoked, each CPU is
- * guaranteed to have executed a full memory barrier since the end of its
- * last RCU read-side critical section whose beginning preceded the call
- * to call_rcu(). It also means that each CPU executing an RCU read-side
- * critical section that continues beyond the start of "func()" must have
- * executed a memory barrier after the call_rcu() but before the beginning
- * of that RCU 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 call_rcu() and CPU B invoked the
- * resulting RCU callback function "func()", then both CPU A and CPU B are
- * guaranteed to execute a full memory barrier during the time interval
- * between the call to call_rcu() and the invocation of "func()" -- even
- * if CPU A and CPU B are the same CPU (but again only if the system has
- * more than one CPU).
- *
- * Implementation of these memory-ordering guarantees is described here:
- * Documentation/RCU/Design/Memory-Ordering/Tree-RCU-Memory-Ordering.rst.
- */
-void call_rcu(struct rcu_head *head, rcu_callback_t func)
+static void
+__call_rcu_common(struct rcu_head *head, rcu_callback_t func, bool lazy)
{
static atomic_t doublefrees;
unsigned long flags;
@@ -2809,7 +2766,7 @@ void call_rcu(struct rcu_head *head, rcu_callback_t func)
}
check_cb_ovld(rdp);
- if (rcu_nocb_try_bypass(rdp, head, &was_alldone, flags))
+ if (rcu_nocb_try_bypass(rdp, head, &was_alldone, flags, lazy))
return; // Enqueued onto ->nocb_bypass, so just leave.
// If no-CBs CPU gets here, rcu_nocb_try_bypass() acquired ->nocb_lock.
rcu_segcblist_enqueue(&rdp->cblist, head);
@@ -2831,8 +2788,84 @@ void call_rcu(struct rcu_head *head, rcu_callback_t func)
local_irq_restore(flags);
}
}
-EXPORT_SYMBOL_GPL(call_rcu);
+#ifdef CONFIG_RCU_LAZY
+/**
+ * call_rcu_hurry() - Queue RCU callback for invocation after grace period, and
+ * flush all lazy callbacks (including the new one) to the main ->cblist while
+ * doing so.
+ *
+ * @head: structure to be used for queueing the RCU updates.
+ * @func: actual callback function to be invoked after the grace period
+ *
+ * The callback function will be invoked some time after a full grace
+ * period elapses, in other words after all pre-existing RCU read-side
+ * critical sections have completed.
+ *
+ * Use this API instead of call_rcu() if you don't want the callback to be
+ * invoked after very long periods of time, which can happen on systems without
+ * memory pressure and on systems which are lightly loaded or mostly idle.
+ * This function will cause callbacks to be invoked sooner than later at the
+ * expense of extra power. Other than that, this function is identical to, and
+ * reuses call_rcu()'s logic. Refer to call_rcu() for more details about memory
+ * ordering and other functionality.
+ */
+void call_rcu_hurry(struct rcu_head *head, rcu_callback_t func)
+{
+ return __call_rcu_common(head, func, false);
+}
+EXPORT_SYMBOL_GPL(call_rcu_hurry);
+#endif
+
+/**
+ * call_rcu() - Queue an RCU callback for invocation after a grace period.
+ * By default the callbacks are 'lazy' and are kept hidden from the main
+ * ->cblist to prevent starting of grace periods too soon.
+ * If you desire grace periods to start very soon, use call_rcu_hurry().
+ *
+ * @head: structure to be used for queueing the RCU updates.
+ * @func: actual callback function to be invoked after the grace period
+ *
+ * The callback function will be invoked some time after a full grace
+ * period elapses, in other words after all pre-existing RCU read-side
+ * critical sections have completed. However, the callback function
+ * might well execute concurrently with RCU read-side critical sections
+ * that started after call_rcu() was invoked.
+ *
+ * RCU read-side critical sections are delimited by rcu_read_lock()
+ * and rcu_read_unlock(), and may be nested. In addition, but only in
+ * v5.0 and later, regions of code across which interrupts, preemption,
+ * or softirqs have been disabled also serve as RCU read-side critical
+ * sections. This includes hardware interrupt handlers, softirq handlers,
+ * and NMI handlers.
+ *
+ * Note that all CPUs must agree that the grace period extended beyond
+ * all pre-existing RCU read-side critical section. On systems with more
+ * than one CPU, this means that when "func()" is invoked, each CPU is
+ * guaranteed to have executed a full memory barrier since the end of its
+ * last RCU read-side critical section whose beginning preceded the call
+ * to call_rcu(). It also means that each CPU executing an RCU read-side
+ * critical section that continues beyond the start of "func()" must have
+ * executed a memory barrier after the call_rcu() but before the beginning
+ * of that RCU 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 call_rcu() and CPU B invoked the
+ * resulting RCU callback function "func()", then both CPU A and CPU B are
+ * guaranteed to execute a full memory barrier during the time interval
+ * between the call to call_rcu() and the invocation of "func()" -- even
+ * if CPU A and CPU B are the same CPU (but again only if the system has
+ * more than one CPU).
+ *
+ * Implementation of these memory-ordering guarantees is described here:
+ * Documentation/RCU/Design/Memory-Ordering/Tree-RCU-Memory-Ordering.rst.
+ */
+void call_rcu(struct rcu_head *head, rcu_callback_t func)
+{
+ return __call_rcu_common(head, func, IS_ENABLED(CONFIG_RCU_LAZY));
+}
+EXPORT_SYMBOL_GPL(call_rcu);
/* Maximum number of jiffies to wait before draining a batch. */
#define KFREE_DRAIN_JIFFIES (5 * HZ)
@@ -3507,7 +3540,7 @@ void synchronize_rcu(void)
if (rcu_gp_is_expedited())
synchronize_rcu_expedited();
else
- wait_rcu_gp(call_rcu);
+ wait_rcu_gp(call_rcu_hurry);
return;
}
@@ -3894,6 +3927,8 @@ static void rcu_barrier_entrain(struct rcu_data *rdp)
{
unsigned long gseq = READ_ONCE(rcu_state.barrier_sequence);
unsigned long lseq = READ_ONCE(rdp->barrier_seq_snap);
+ bool wake_nocb = false;
+ bool was_alldone = false;
lockdep_assert_held(&rcu_state.barrier_lock);
if (rcu_seq_state(lseq) || !rcu_seq_state(gseq) || rcu_seq_ctr(lseq) != rcu_seq_ctr(gseq))
@@ -3902,7 +3937,14 @@ static void rcu_barrier_entrain(struct rcu_data *rdp)
rdp->barrier_head.func = rcu_barrier_callback;
debug_rcu_head_queue(&rdp->barrier_head);
rcu_nocb_lock(rdp);
- WARN_ON_ONCE(!rcu_nocb_flush_bypass(rdp, NULL, jiffies));
+ /*
+ * Flush bypass and wakeup rcuog if we add callbacks to an empty regular
+ * queue. This way we don't wait for bypass timer that can reach seconds
+ * if it's fully lazy.
+ */
+ was_alldone = rcu_rdp_is_offloaded(rdp) && !rcu_segcblist_pend_cbs(&rdp->cblist);
+ WARN_ON_ONCE(!rcu_nocb_flush_bypass(rdp, NULL, jiffies, false));
+ wake_nocb = was_alldone && rcu_segcblist_pend_cbs(&rdp->cblist);
if (rcu_segcblist_entrain(&rdp->cblist, &rdp->barrier_head)) {
atomic_inc(&rcu_state.barrier_cpu_count);
} else {
@@ -3910,6 +3952,8 @@ static void rcu_barrier_entrain(struct rcu_data *rdp)
rcu_barrier_trace(TPS("IRQNQ"), -1, rcu_state.barrier_sequence);
}
rcu_nocb_unlock(rdp);
+ if (wake_nocb)
+ wake_nocb_gp(rdp, false);
smp_store_release(&rdp->barrier_seq_snap, gseq);
}
@@ -4276,8 +4320,6 @@ void rcu_report_dead(unsigned int cpu)
// Do any dangling deferred wakeups.
do_nocb_deferred_wakeup(rdp);
- /* QS for any half-done expedited grace period. */
- rcu_report_exp_rdp(rdp);
rcu_preempt_deferred_qs(current);
/* Remove outgoing CPU from mask in the leaf rcu_node structure. */
@@ -4325,7 +4367,7 @@ void rcutree_migrate_callbacks(int cpu)
my_rdp = this_cpu_ptr(&rcu_data);
my_rnp = my_rdp->mynode;
rcu_nocb_lock(my_rdp); /* irqs already disabled. */
- WARN_ON_ONCE(!rcu_nocb_flush_bypass(my_rdp, NULL, jiffies));
+ WARN_ON_ONCE(!rcu_nocb_flush_bypass(my_rdp, NULL, jiffies, false));
raw_spin_lock_rcu_node(my_rnp); /* irqs already disabled. */
/* Leverage recent GPs and set GP for new callbacks. */
needwake = rcu_advance_cbs(my_rnp, rdp) ||
diff --git a/kernel/rcu/tree.h b/kernel/rcu/tree.h
index d4a97e40ea9c..fcb5d696eb17 100644
--- a/kernel/rcu/tree.h
+++ b/kernel/rcu/tree.h
@@ -263,14 +263,16 @@ struct rcu_data {
unsigned long last_fqs_resched; /* Time of last rcu_resched(). */
unsigned long last_sched_clock; /* Jiffies of last rcu_sched_clock_irq(). */
+ long lazy_len; /* Length of buffered lazy callbacks. */
int cpu;
};
/* Values for nocb_defer_wakeup field in struct rcu_data. */
#define RCU_NOCB_WAKE_NOT 0
#define RCU_NOCB_WAKE_BYPASS 1
-#define RCU_NOCB_WAKE 2
-#define RCU_NOCB_WAKE_FORCE 3
+#define RCU_NOCB_WAKE_LAZY 2
+#define RCU_NOCB_WAKE 3
+#define RCU_NOCB_WAKE_FORCE 4
#define RCU_JIFFIES_TILL_FORCE_QS (1 + (HZ > 250) + (HZ > 500))
/* For jiffies_till_first_fqs and */
@@ -439,10 +441,12 @@ static void zero_cpu_stall_ticks(struct rcu_data *rdp);
static struct swait_queue_head *rcu_nocb_gp_get(struct rcu_node *rnp);
static void rcu_nocb_gp_cleanup(struct swait_queue_head *sq);
static void rcu_init_one_nocb(struct rcu_node *rnp);
+static bool wake_nocb_gp(struct rcu_data *rdp, bool force);
static bool rcu_nocb_flush_bypass(struct rcu_data *rdp, struct rcu_head *rhp,
- unsigned long j);
+ unsigned long j, bool lazy);
static bool rcu_nocb_try_bypass(struct rcu_data *rdp, struct rcu_head *rhp,
- bool *was_alldone, unsigned long flags);
+ bool *was_alldone, unsigned long flags,
+ bool lazy);
static void __call_rcu_nocb_wake(struct rcu_data *rdp, bool was_empty,
unsigned long flags);
static int rcu_nocb_need_deferred_wakeup(struct rcu_data *rdp, int level);
diff --git a/kernel/rcu/tree_exp.h b/kernel/rcu/tree_exp.h
index 18e9b4cd78ef..ed6c3cce28f2 100644
--- a/kernel/rcu/tree_exp.h
+++ b/kernel/rcu/tree_exp.h
@@ -937,7 +937,7 @@ void synchronize_rcu_expedited(void)
/* If expedited grace periods are prohibited, fall back to normal. */
if (rcu_gp_is_normal()) {
- wait_rcu_gp(call_rcu);
+ wait_rcu_gp(call_rcu_hurry);
return;
}
diff --git a/kernel/rcu/tree_nocb.h b/kernel/rcu/tree_nocb.h
index 0a5f0ef41484..9e1c8caec5ce 100644
--- a/kernel/rcu/tree_nocb.h
+++ b/kernel/rcu/tree_nocb.h
@@ -257,6 +257,31 @@ static bool wake_nocb_gp(struct rcu_data *rdp, bool force)
}
/*
+ * LAZY_FLUSH_JIFFIES decides the maximum amount of time that
+ * can elapse before lazy callbacks are flushed. Lazy callbacks
+ * could be flushed much earlier for a number of other reasons
+ * however, LAZY_FLUSH_JIFFIES will ensure no lazy callbacks are
+ * left unsubmitted to RCU after those many jiffies.
+ */
+#define LAZY_FLUSH_JIFFIES (10 * HZ)
+static unsigned long jiffies_till_flush = LAZY_FLUSH_JIFFIES;
+
+#ifdef CONFIG_RCU_LAZY
+// To be called only from test code.
+void rcu_lazy_set_jiffies_till_flush(unsigned long jif)
+{
+ jiffies_till_flush = jif;
+}
+EXPORT_SYMBOL(rcu_lazy_set_jiffies_till_flush);
+
+unsigned long rcu_lazy_get_jiffies_till_flush(void)
+{
+ return jiffies_till_flush;
+}
+EXPORT_SYMBOL(rcu_lazy_get_jiffies_till_flush);
+#endif
+
+/*
* Arrange to wake the GP kthread for this NOCB group at some future
* time when it is safe to do so.
*/
@@ -269,10 +294,14 @@ static void wake_nocb_gp_defer(struct rcu_data *rdp, int waketype,
raw_spin_lock_irqsave(&rdp_gp->nocb_gp_lock, flags);
/*
- * Bypass wakeup overrides previous deferments. In case
- * of callback storm, no need to wake up too early.
+ * Bypass wakeup overrides previous deferments. In case of
+ * callback storms, no need to wake up too early.
*/
- if (waketype == RCU_NOCB_WAKE_BYPASS) {
+ if (waketype == RCU_NOCB_WAKE_LAZY &&
+ rdp->nocb_defer_wakeup == RCU_NOCB_WAKE_NOT) {
+ mod_timer(&rdp_gp->nocb_timer, jiffies + jiffies_till_flush);
+ WRITE_ONCE(rdp_gp->nocb_defer_wakeup, waketype);
+ } else if (waketype == RCU_NOCB_WAKE_BYPASS) {
mod_timer(&rdp_gp->nocb_timer, jiffies + 2);
WRITE_ONCE(rdp_gp->nocb_defer_wakeup, waketype);
} else {
@@ -293,12 +322,16 @@ static void wake_nocb_gp_defer(struct rcu_data *rdp, int waketype,
* proves to be initially empty, just return false because the no-CB GP
* kthread may need to be awakened in this case.
*
+ * Return true if there was something to be flushed and it succeeded, otherwise
+ * false.
+ *
* Note that this function always returns true if rhp is NULL.
*/
-static bool rcu_nocb_do_flush_bypass(struct rcu_data *rdp, struct rcu_head *rhp,
- unsigned long j)
+static bool rcu_nocb_do_flush_bypass(struct rcu_data *rdp, struct rcu_head *rhp_in,
+ unsigned long j, bool lazy)
{
struct rcu_cblist rcl;
+ struct rcu_head *rhp = rhp_in;
WARN_ON_ONCE(!rcu_rdp_is_offloaded(rdp));
rcu_lockdep_assert_cblist_protected(rdp);
@@ -310,7 +343,20 @@ static bool rcu_nocb_do_flush_bypass(struct rcu_data *rdp, struct rcu_head *rhp,
/* Note: ->cblist.len already accounts for ->nocb_bypass contents. */
if (rhp)
rcu_segcblist_inc_len(&rdp->cblist); /* Must precede enqueue. */
+
+ /*
+ * If the new CB requested was a lazy one, queue it onto the main
+ * ->cblist so that we can take advantage of the grace-period that will
+ * happen regardless. But queue it onto the bypass list first so that
+ * the lazy CB is ordered with the existing CBs in the bypass list.
+ */
+ if (lazy && rhp) {
+ rcu_cblist_enqueue(&rdp->nocb_bypass, rhp);
+ rhp = NULL;
+ }
rcu_cblist_flush_enqueue(&rcl, &rdp->nocb_bypass, rhp);
+ WRITE_ONCE(rdp->lazy_len, 0);
+
rcu_segcblist_insert_pend_cbs(&rdp->cblist, &rcl);
WRITE_ONCE(rdp->nocb_bypass_first, j);
rcu_nocb_bypass_unlock(rdp);
@@ -326,13 +372,13 @@ static bool rcu_nocb_do_flush_bypass(struct rcu_data *rdp, struct rcu_head *rhp,
* Note that this function always returns true if rhp is NULL.
*/
static bool rcu_nocb_flush_bypass(struct rcu_data *rdp, struct rcu_head *rhp,
- unsigned long j)
+ unsigned long j, bool lazy)
{
if (!rcu_rdp_is_offloaded(rdp))
return true;
rcu_lockdep_assert_cblist_protected(rdp);
rcu_nocb_bypass_lock(rdp);
- return rcu_nocb_do_flush_bypass(rdp, rhp, j);
+ return rcu_nocb_do_flush_bypass(rdp, rhp, j, lazy);
}
/*
@@ -345,7 +391,7 @@ static void rcu_nocb_try_flush_bypass(struct rcu_data *rdp, unsigned long j)
if (!rcu_rdp_is_offloaded(rdp) ||
!rcu_nocb_bypass_trylock(rdp))
return;
- WARN_ON_ONCE(!rcu_nocb_do_flush_bypass(rdp, NULL, j));
+ WARN_ON_ONCE(!rcu_nocb_do_flush_bypass(rdp, NULL, j, false));
}
/*
@@ -367,12 +413,14 @@ static void rcu_nocb_try_flush_bypass(struct rcu_data *rdp, unsigned long j)
* there is only one CPU in operation.
*/
static bool rcu_nocb_try_bypass(struct rcu_data *rdp, struct rcu_head *rhp,
- bool *was_alldone, unsigned long flags)
+ bool *was_alldone, unsigned long flags,
+ bool lazy)
{
unsigned long c;
unsigned long cur_gp_seq;
unsigned long j = jiffies;
long ncbs = rcu_cblist_n_cbs(&rdp->nocb_bypass);
+ bool bypass_is_lazy = (ncbs == READ_ONCE(rdp->lazy_len));
lockdep_assert_irqs_disabled();
@@ -417,24 +465,29 @@ static bool rcu_nocb_try_bypass(struct rcu_data *rdp, struct rcu_head *rhp,
// If there hasn't yet been all that many ->cblist enqueues
// this jiffy, tell the caller to enqueue onto ->cblist. But flush
// ->nocb_bypass first.
- if (rdp->nocb_nobypass_count < nocb_nobypass_lim_per_jiffy) {
+ // Lazy CBs throttle this back and do immediate bypass queuing.
+ if (rdp->nocb_nobypass_count < nocb_nobypass_lim_per_jiffy && !lazy) {
rcu_nocb_lock(rdp);
*was_alldone = !rcu_segcblist_pend_cbs(&rdp->cblist);
if (*was_alldone)
trace_rcu_nocb_wake(rcu_state.name, rdp->cpu,
TPS("FirstQ"));
- WARN_ON_ONCE(!rcu_nocb_flush_bypass(rdp, NULL, j));
+
+ WARN_ON_ONCE(!rcu_nocb_flush_bypass(rdp, NULL, j, false));
WARN_ON_ONCE(rcu_cblist_n_cbs(&rdp->nocb_bypass));
return false; // Caller must enqueue the callback.
}
// If ->nocb_bypass has been used too long or is too full,
// flush ->nocb_bypass to ->cblist.
- if ((ncbs && j != READ_ONCE(rdp->nocb_bypass_first)) ||
+ if ((ncbs && !bypass_is_lazy && j != READ_ONCE(rdp->nocb_bypass_first)) ||
+ (ncbs && bypass_is_lazy &&
+ (time_after(j, READ_ONCE(rdp->nocb_bypass_first) + jiffies_till_flush))) ||
ncbs >= qhimark) {
rcu_nocb_lock(rdp);
- if (!rcu_nocb_flush_bypass(rdp, rhp, j)) {
- *was_alldone = !rcu_segcblist_pend_cbs(&rdp->cblist);
+ *was_alldone = !rcu_segcblist_pend_cbs(&rdp->cblist);
+
+ if (!rcu_nocb_flush_bypass(rdp, rhp, j, lazy)) {
if (*was_alldone)
trace_rcu_nocb_wake(rcu_state.name, rdp->cpu,
TPS("FirstQ"));
@@ -447,7 +500,12 @@ static bool rcu_nocb_try_bypass(struct rcu_data *rdp, struct rcu_head *rhp,
rcu_advance_cbs_nowake(rdp->mynode, rdp);
rdp->nocb_gp_adv_time = j;
}
- rcu_nocb_unlock_irqrestore(rdp, flags);
+
+ // The flush succeeded and we moved CBs into the regular list.
+ // Don't wait for the wake up timer as it may be too far ahead.
+ // Wake up the GP thread now instead, if the cblist was empty.
+ __call_rcu_nocb_wake(rdp, *was_alldone, flags);
+
return true; // Callback already enqueued.
}
@@ -457,13 +515,24 @@ static bool rcu_nocb_try_bypass(struct rcu_data *rdp, struct rcu_head *rhp,
ncbs = rcu_cblist_n_cbs(&rdp->nocb_bypass);
rcu_segcblist_inc_len(&rdp->cblist); /* Must precede enqueue. */
rcu_cblist_enqueue(&rdp->nocb_bypass, rhp);
+
+ if (lazy)
+ WRITE_ONCE(rdp->lazy_len, rdp->lazy_len + 1);
+
if (!ncbs) {
WRITE_ONCE(rdp->nocb_bypass_first, j);
trace_rcu_nocb_wake(rcu_state.name, rdp->cpu, TPS("FirstBQ"));
}
rcu_nocb_bypass_unlock(rdp);
smp_mb(); /* Order enqueue before wake. */
- if (ncbs) {
+ // A wake up of the grace period kthread or timer adjustment
+ // needs to be done only if:
+ // 1. Bypass list was fully empty before (this is the first
+ // bypass list entry), or:
+ // 2. Both of these conditions are met:
+ // a. The bypass list previously had only lazy CBs, and:
+ // b. The new CB is non-lazy.
+ if (ncbs && (!bypass_is_lazy || lazy)) {
local_irq_restore(flags);
} else {
// No-CBs GP kthread might be indefinitely asleep, if so, wake.
@@ -491,8 +560,10 @@ static void __call_rcu_nocb_wake(struct rcu_data *rdp, bool was_alldone,
unsigned long flags)
__releases(rdp->nocb_lock)
{
+ long bypass_len;
unsigned long cur_gp_seq;
unsigned long j;
+ long lazy_len;
long len;
struct task_struct *t;
@@ -506,9 +577,16 @@ static void __call_rcu_nocb_wake(struct rcu_data *rdp, bool was_alldone,
}
// Need to actually to a wakeup.
len = rcu_segcblist_n_cbs(&rdp->cblist);
+ bypass_len = rcu_cblist_n_cbs(&rdp->nocb_bypass);
+ lazy_len = READ_ONCE(rdp->lazy_len);
if (was_alldone) {
rdp->qlen_last_fqs_check = len;
- if (!irqs_disabled_flags(flags)) {
+ // Only lazy CBs in bypass list
+ if (lazy_len && bypass_len == lazy_len) {
+ rcu_nocb_unlock_irqrestore(rdp, flags);
+ wake_nocb_gp_defer(rdp, RCU_NOCB_WAKE_LAZY,
+ TPS("WakeLazy"));
+ } else if (!irqs_disabled_flags(flags)) {
/* ... if queue was empty ... */
rcu_nocb_unlock_irqrestore(rdp, flags);
wake_nocb_gp(rdp, false);
@@ -599,12 +677,12 @@ static void nocb_gp_sleep(struct rcu_data *my_rdp, int cpu)
static void nocb_gp_wait(struct rcu_data *my_rdp)
{
bool bypass = false;
- long bypass_ncbs;
int __maybe_unused cpu = my_rdp->cpu;
unsigned long cur_gp_seq;
unsigned long flags;
bool gotcbs = false;
unsigned long j = jiffies;
+ bool lazy = false;
bool needwait_gp = false; // This prevents actual uninitialized use.
bool needwake;
bool needwake_gp;
@@ -634,24 +712,43 @@ static void nocb_gp_wait(struct rcu_data *my_rdp)
* won't be ignored for long.
*/
list_for_each_entry(rdp, &my_rdp->nocb_head_rdp, nocb_entry_rdp) {
+ long bypass_ncbs;
+ bool flush_bypass = false;
+ long lazy_ncbs;
+
trace_rcu_nocb_wake(rcu_state.name, rdp->cpu, TPS("Check"));
rcu_nocb_lock_irqsave(rdp, flags);
lockdep_assert_held(&rdp->nocb_lock);
bypass_ncbs = rcu_cblist_n_cbs(&rdp->nocb_bypass);
- if (bypass_ncbs &&
+ lazy_ncbs = READ_ONCE(rdp->lazy_len);
+
+ if (bypass_ncbs && (lazy_ncbs == bypass_ncbs) &&
+ (time_after(j, READ_ONCE(rdp->nocb_bypass_first) + jiffies_till_flush) ||
+ bypass_ncbs > 2 * qhimark)) {
+ flush_bypass = true;
+ } else if (bypass_ncbs && (lazy_ncbs != bypass_ncbs) &&
(time_after(j, READ_ONCE(rdp->nocb_bypass_first) + 1) ||
bypass_ncbs > 2 * qhimark)) {
- // Bypass full or old, so flush it.
- (void)rcu_nocb_try_flush_bypass(rdp, j);
- bypass_ncbs = rcu_cblist_n_cbs(&rdp->nocb_bypass);
+ flush_bypass = true;
} else if (!bypass_ncbs && rcu_segcblist_empty(&rdp->cblist)) {
rcu_nocb_unlock_irqrestore(rdp, flags);
continue; /* No callbacks here, try next. */
}
+
+ if (flush_bypass) {
+ // Bypass full or old, so flush it.
+ (void)rcu_nocb_try_flush_bypass(rdp, j);
+ bypass_ncbs = rcu_cblist_n_cbs(&rdp->nocb_bypass);
+ lazy_ncbs = READ_ONCE(rdp->lazy_len);
+ }
+
if (bypass_ncbs) {
trace_rcu_nocb_wake(rcu_state.name, rdp->cpu,
- TPS("Bypass"));
- bypass = true;
+ bypass_ncbs == lazy_ncbs ? TPS("Lazy") : TPS("Bypass"));
+ if (bypass_ncbs == lazy_ncbs)
+ lazy = true;
+ else
+ bypass = true;
}
rnp = rdp->mynode;
@@ -699,12 +796,20 @@ static void nocb_gp_wait(struct rcu_data *my_rdp)
my_rdp->nocb_gp_gp = needwait_gp;
my_rdp->nocb_gp_seq = needwait_gp ? wait_gp_seq : 0;
- if (bypass && !rcu_nocb_poll) {
- // At least one child with non-empty ->nocb_bypass, so set
- // timer in order to avoid stranding its callbacks.
- wake_nocb_gp_defer(my_rdp, RCU_NOCB_WAKE_BYPASS,
- TPS("WakeBypassIsDeferred"));
+ // At least one child with non-empty ->nocb_bypass, so set
+ // timer in order to avoid stranding its callbacks.
+ if (!rcu_nocb_poll) {
+ // If bypass list only has lazy CBs. Add a deferred lazy wake up.
+ if (lazy && !bypass) {
+ wake_nocb_gp_defer(my_rdp, RCU_NOCB_WAKE_LAZY,
+ TPS("WakeLazyIsDeferred"));
+ // Otherwise add a deferred bypass wake up.
+ } else if (bypass) {
+ wake_nocb_gp_defer(my_rdp, RCU_NOCB_WAKE_BYPASS,
+ TPS("WakeBypassIsDeferred"));
+ }
}
+
if (rcu_nocb_poll) {
/* Polling, so trace if first poll in the series. */
if (gotcbs)
@@ -1030,7 +1135,7 @@ static long rcu_nocb_rdp_deoffload(void *arg)
* return false, which means that future calls to rcu_nocb_try_bypass()
* will refuse to put anything into the bypass.
*/
- WARN_ON_ONCE(!rcu_nocb_flush_bypass(rdp, NULL, jiffies));
+ WARN_ON_ONCE(!rcu_nocb_flush_bypass(rdp, NULL, jiffies, false));
/*
* Start with invoking rcu_core() early. This way if the current thread
* happens to preempt an ongoing call to rcu_core() in the middle,
@@ -1207,47 +1312,87 @@ int rcu_nocb_cpu_offload(int cpu)
}
EXPORT_SYMBOL_GPL(rcu_nocb_cpu_offload);
-void __init rcu_init_nohz(void)
+static unsigned long
+lazy_rcu_shrink_count(struct shrinker *shrink, struct shrink_control *sc)
{
int cpu;
- bool need_rcu_nocb_mask = false;
- bool offload_all = false;
- struct rcu_data *rdp;
+ unsigned long count = 0;
-#if defined(CONFIG_RCU_NOCB_CPU_DEFAULT_ALL)
- if (!rcu_state.nocb_is_setup) {
- need_rcu_nocb_mask = true;
- offload_all = true;
+ /* Snapshot count of all CPUs */
+ for_each_possible_cpu(cpu) {
+ struct rcu_data *rdp = per_cpu_ptr(&rcu_data, cpu);
+
+ count += READ_ONCE(rdp->lazy_len);
}
-#endif /* #if defined(CONFIG_RCU_NOCB_CPU_DEFAULT_ALL) */
-#if defined(CONFIG_NO_HZ_FULL)
- if (tick_nohz_full_running && !cpumask_empty(tick_nohz_full_mask)) {
- need_rcu_nocb_mask = true;
- offload_all = false; /* NO_HZ_FULL has its own mask. */
+ return count ? count : SHRINK_EMPTY;
+}
+
+static unsigned long
+lazy_rcu_shrink_scan(struct shrinker *shrink, struct shrink_control *sc)
+{
+ int cpu;
+ unsigned long flags;
+ unsigned long count = 0;
+
+ /* Snapshot count of all CPUs */
+ for_each_possible_cpu(cpu) {
+ struct rcu_data *rdp = per_cpu_ptr(&rcu_data, cpu);
+ int _count = READ_ONCE(rdp->lazy_len);
+
+ if (_count == 0)
+ continue;
+ rcu_nocb_lock_irqsave(rdp, flags);
+ WRITE_ONCE(rdp->lazy_len, 0);
+ rcu_nocb_unlock_irqrestore(rdp, flags);
+ wake_nocb_gp(rdp, false);
+ sc->nr_to_scan -= _count;
+ count += _count;
+ if (sc->nr_to_scan <= 0)
+ break;
}
-#endif /* #if defined(CONFIG_NO_HZ_FULL) */
+ return count ? count : SHRINK_STOP;
+}
+
+static struct shrinker lazy_rcu_shrinker = {
+ .count_objects = lazy_rcu_shrink_count,
+ .scan_objects = lazy_rcu_shrink_scan,
+ .batch = 0,
+ .seeks = DEFAULT_SEEKS,
+};
+
+void __init rcu_init_nohz(void)
+{
+ int cpu;
+ struct rcu_data *rdp;
+ const struct cpumask *cpumask = NULL;
+
+#if defined(CONFIG_NO_HZ_FULL)
+ if (tick_nohz_full_running && !cpumask_empty(tick_nohz_full_mask))
+ cpumask = tick_nohz_full_mask;
+#endif
- if (need_rcu_nocb_mask) {
+ if (IS_ENABLED(CONFIG_RCU_NOCB_CPU_DEFAULT_ALL) &&
+ !rcu_state.nocb_is_setup && !cpumask)
+ cpumask = cpu_possible_mask;
+
+ if (cpumask) {
if (!cpumask_available(rcu_nocb_mask)) {
if (!zalloc_cpumask_var(&rcu_nocb_mask, GFP_KERNEL)) {
pr_info("rcu_nocb_mask allocation failed, callback offloading disabled.\n");
return;
}
}
+
+ cpumask_or(rcu_nocb_mask, rcu_nocb_mask, cpumask);
rcu_state.nocb_is_setup = true;
}
if (!rcu_state.nocb_is_setup)
return;
-#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 (offload_all)
- cpumask_setall(rcu_nocb_mask);
+ if (register_shrinker(&lazy_rcu_shrinker, "rcu-lazy"))
+ pr_err("Failed to register lazy_rcu shrinker!\n");
if (!cpumask_subset(rcu_nocb_mask, cpu_possible_mask)) {
pr_info("\tNote: kernel parameter 'rcu_nocbs=', 'nohz_full', or 'isolcpus=' contains nonexistent CPUs.\n");
@@ -1284,6 +1429,7 @@ static void __init rcu_boot_init_nocb_percpu_data(struct rcu_data *rdp)
raw_spin_lock_init(&rdp->nocb_gp_lock);
timer_setup(&rdp->nocb_timer, do_nocb_deferred_wakeup_timer, 0);
rcu_cblist_init(&rdp->nocb_bypass);
+ WRITE_ONCE(rdp->lazy_len, 0);
mutex_init(&rdp->nocb_gp_kthread_mutex);
}
@@ -1564,14 +1710,19 @@ static void rcu_init_one_nocb(struct rcu_node *rnp)
{
}
+static bool wake_nocb_gp(struct rcu_data *rdp, bool force)
+{
+ return false;
+}
+
static bool rcu_nocb_flush_bypass(struct rcu_data *rdp, struct rcu_head *rhp,
- unsigned long j)
+ unsigned long j, bool lazy)
{
return true;
}
static bool rcu_nocb_try_bypass(struct rcu_data *rdp, struct rcu_head *rhp,
- bool *was_alldone, unsigned long flags)
+ bool *was_alldone, unsigned long flags, bool lazy)
{
return false;
}
diff --git a/kernel/rcu/tree_plugin.h b/kernel/rcu/tree_plugin.h
index e3142ee35fc6..7b0fe741a088 100644
--- a/kernel/rcu/tree_plugin.h
+++ b/kernel/rcu/tree_plugin.h
@@ -1221,11 +1221,13 @@ static void rcu_spawn_one_boost_kthread(struct rcu_node *rnp)
* We don't include outgoingcpu in the affinity set, use -1 if there is
* no outgoing CPU. If there are no CPUs left in the affinity set,
* this function allows the kthread to execute on any CPU.
+ *
+ * Any future concurrent calls are serialized via ->boost_kthread_mutex.
*/
static void rcu_boost_kthread_setaffinity(struct rcu_node *rnp, int outgoingcpu)
{
struct task_struct *t = rnp->boost_kthread_task;
- unsigned long mask = rcu_rnp_online_cpus(rnp);
+ unsigned long mask;
cpumask_var_t cm;
int cpu;
@@ -1234,6 +1236,7 @@ static void rcu_boost_kthread_setaffinity(struct rcu_node *rnp, int outgoingcpu)
if (!zalloc_cpumask_var(&cm, GFP_KERNEL))
return;
mutex_lock(&rnp->boost_kthread_mutex);
+ mask = rcu_rnp_online_cpus(rnp);
for_each_leaf_node_possible_cpu(rnp, cpu)
if ((mask & leaf_node_cpu_bit(rnp, cpu)) &&
cpu != outgoingcpu)
diff --git a/kernel/rseq.c b/kernel/rseq.c
index bda8175f8f99..d38ab944105d 100644
--- a/kernel/rseq.c
+++ b/kernel/rseq.c
@@ -171,12 +171,27 @@ static int rseq_get_rseq_cs(struct task_struct *t, struct rseq_cs *rseq_cs)
return 0;
}
+static bool rseq_warn_flags(const char *str, u32 flags)
+{
+ u32 test_flags;
+
+ if (!flags)
+ return false;
+ test_flags = flags & RSEQ_CS_NO_RESTART_FLAGS;
+ if (test_flags)
+ pr_warn_once("Deprecated flags (%u) in %s ABI structure", test_flags, str);
+ test_flags = flags & ~RSEQ_CS_NO_RESTART_FLAGS;
+ if (test_flags)
+ pr_warn_once("Unknown flags (%u) in %s ABI structure", test_flags, str);
+ return true;
+}
+
static int rseq_need_restart(struct task_struct *t, u32 cs_flags)
{
u32 flags, event_mask;
int ret;
- if (WARN_ON_ONCE(cs_flags & RSEQ_CS_NO_RESTART_FLAGS) || cs_flags)
+ if (rseq_warn_flags("rseq_cs", cs_flags))
return -EINVAL;
/* Get thread flags. */
@@ -184,7 +199,7 @@ static int rseq_need_restart(struct task_struct *t, u32 cs_flags)
if (ret)
return ret;
- if (WARN_ON_ONCE(flags & RSEQ_CS_NO_RESTART_FLAGS) || flags)
+ if (rseq_warn_flags("rseq", flags))
return -EINVAL;
/*
diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index 5800b0623ff3..daff72f00385 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -4200,6 +4200,40 @@ out:
return success;
}
+static bool __task_needs_rq_lock(struct task_struct *p)
+{
+ unsigned int state = READ_ONCE(p->__state);
+
+ /*
+ * Since pi->lock blocks try_to_wake_up(), we don't need rq->lock when
+ * the task is blocked. Make sure to check @state since ttwu() can drop
+ * locks at the end, see ttwu_queue_wakelist().
+ */
+ if (state == TASK_RUNNING || state == TASK_WAKING)
+ return true;
+
+ /*
+ * Ensure we load p->on_rq after p->__state, otherwise it would be
+ * possible to, falsely, observe p->on_rq == 0.
+ *
+ * See try_to_wake_up() for a longer comment.
+ */
+ smp_rmb();
+ if (p->on_rq)
+ return true;
+
+#ifdef CONFIG_SMP
+ /*
+ * Ensure the task has finished __schedule() and will not be referenced
+ * anymore. Again, see try_to_wake_up() for a longer comment.
+ */
+ smp_rmb();
+ smp_cond_load_acquire(&p->on_cpu, !VAL);
+#endif
+
+ return false;
+}
+
/**
* task_call_func - Invoke a function on task in fixed state
* @p: Process for which the function is to be invoked, can be @current.
@@ -4217,28 +4251,12 @@ out:
int task_call_func(struct task_struct *p, task_call_f func, void *arg)
{
struct rq *rq = NULL;
- unsigned int state;
struct rq_flags rf;
int ret;
raw_spin_lock_irqsave(&p->pi_lock, rf.flags);
- state = READ_ONCE(p->__state);
-
- /*
- * Ensure we load p->on_rq after p->__state, otherwise it would be
- * possible to, falsely, observe p->on_rq == 0.
- *
- * See try_to_wake_up() for a longer comment.
- */
- smp_rmb();
-
- /*
- * Since pi->lock blocks try_to_wake_up(), we don't need rq->lock when
- * the task is blocked. Make sure to check @state since ttwu() can drop
- * locks at the end, see ttwu_queue_wakelist().
- */
- if (state == TASK_RUNNING || state == TASK_WAKING || p->on_rq)
+ if (__task_needs_rq_lock(p))
rq = __task_rq_lock(p, &rf);
/*
@@ -4823,10 +4841,10 @@ static inline void finish_task(struct task_struct *prev)
#ifdef CONFIG_SMP
-static void do_balance_callbacks(struct rq *rq, struct callback_head *head)
+static void do_balance_callbacks(struct rq *rq, struct balance_callback *head)
{
void (*func)(struct rq *rq);
- struct callback_head *next;
+ struct balance_callback *next;
lockdep_assert_rq_held(rq);
@@ -4853,15 +4871,15 @@ static void balance_push(struct rq *rq);
* This abuse is tolerated because it places all the unlikely/odd cases behind
* a single test, namely: rq->balance_callback == NULL.
*/
-struct callback_head balance_push_callback = {
+struct balance_callback balance_push_callback = {
.next = NULL,
- .func = (void (*)(struct callback_head *))balance_push,
+ .func = balance_push,
};
-static inline struct callback_head *
+static inline struct balance_callback *
__splice_balance_callbacks(struct rq *rq, bool split)
{
- struct callback_head *head = rq->balance_callback;
+ struct balance_callback *head = rq->balance_callback;
if (likely(!head))
return NULL;
@@ -4883,7 +4901,7 @@ __splice_balance_callbacks(struct rq *rq, bool split)
return head;
}
-static inline struct callback_head *splice_balance_callbacks(struct rq *rq)
+static inline struct balance_callback *splice_balance_callbacks(struct rq *rq)
{
return __splice_balance_callbacks(rq, true);
}
@@ -4893,7 +4911,7 @@ static void __balance_callbacks(struct rq *rq)
do_balance_callbacks(rq, __splice_balance_callbacks(rq, false));
}
-static inline void balance_callbacks(struct rq *rq, struct callback_head *head)
+static inline void balance_callbacks(struct rq *rq, struct balance_callback *head)
{
unsigned long flags;
@@ -4910,12 +4928,12 @@ static inline void __balance_callbacks(struct rq *rq)
{
}
-static inline struct callback_head *splice_balance_callbacks(struct rq *rq)
+static inline struct balance_callback *splice_balance_callbacks(struct rq *rq)
{
return NULL;
}
-static inline void balance_callbacks(struct rq *rq, struct callback_head *head)
+static inline void balance_callbacks(struct rq *rq, struct balance_callback *head)
{
}
@@ -6188,7 +6206,7 @@ static void sched_core_balance(struct rq *rq)
preempt_enable();
}
-static DEFINE_PER_CPU(struct callback_head, core_balance_head);
+static DEFINE_PER_CPU(struct balance_callback, core_balance_head);
static void queue_core_balance(struct rq *rq)
{
@@ -7419,7 +7437,7 @@ static int __sched_setscheduler(struct task_struct *p,
int oldpolicy = -1, policy = attr->sched_policy;
int retval, oldprio, newprio, queued, running;
const struct sched_class *prev_class;
- struct callback_head *head;
+ struct balance_callback *head;
struct rq_flags rf;
int reset_on_fork;
int queue_flags = DEQUEUE_SAVE | DEQUEUE_MOVE | DEQUEUE_NOCLOCK;
diff --git a/kernel/sched/cpufreq_schedutil.c b/kernel/sched/cpufreq_schedutil.c
index 9161d1136d01..1207c78f85c1 100644
--- a/kernel/sched/cpufreq_schedutil.c
+++ b/kernel/sched/cpufreq_schedutil.c
@@ -25,9 +25,6 @@ struct sugov_policy {
unsigned int next_freq;
unsigned int cached_raw_freq;
- /* max CPU capacity, which is equal for all CPUs in freq. domain */
- unsigned long max;
-
/* The next fields are only needed if fast switch cannot be used: */
struct irq_work irq_work;
struct kthread_work work;
@@ -51,6 +48,7 @@ struct sugov_cpu {
unsigned long util;
unsigned long bw_dl;
+ unsigned long max;
/* The field below is for single-CPU policies only: */
#ifdef CONFIG_NO_HZ_COMMON
@@ -160,6 +158,7 @@ static void sugov_get_util(struct sugov_cpu *sg_cpu)
{
struct rq *rq = cpu_rq(sg_cpu->cpu);
+ sg_cpu->max = arch_scale_cpu_capacity(sg_cpu->cpu);
sg_cpu->bw_dl = cpu_bw_dl(rq);
sg_cpu->util = effective_cpu_util(sg_cpu->cpu, cpu_util_cfs(sg_cpu->cpu),
FREQUENCY_UTIL, NULL);
@@ -254,7 +253,6 @@ static void sugov_iowait_boost(struct sugov_cpu *sg_cpu, u64 time,
*/
static void sugov_iowait_apply(struct sugov_cpu *sg_cpu, u64 time)
{
- struct sugov_policy *sg_policy = sg_cpu->sg_policy;
unsigned long boost;
/* No boost currently required */
@@ -282,8 +280,7 @@ static void sugov_iowait_apply(struct sugov_cpu *sg_cpu, u64 time)
* sg_cpu->util is already in capacity scale; convert iowait_boost
* into the same scale so we can compare.
*/
- boost = sg_cpu->iowait_boost * sg_policy->max;
- boost >>= SCHED_CAPACITY_SHIFT;
+ boost = (sg_cpu->iowait_boost * sg_cpu->max) >> SCHED_CAPACITY_SHIFT;
boost = uclamp_rq_util_with(cpu_rq(sg_cpu->cpu), boost, NULL);
if (sg_cpu->util < boost)
sg_cpu->util = boost;
@@ -340,7 +337,7 @@ static void sugov_update_single_freq(struct update_util_data *hook, u64 time,
if (!sugov_update_single_common(sg_cpu, time, flags))
return;
- next_f = get_next_freq(sg_policy, sg_cpu->util, sg_policy->max);
+ next_f = get_next_freq(sg_policy, sg_cpu->util, sg_cpu->max);
/*
* Do not reduce the frequency if the CPU has not been idle
* recently, as the reduction is likely to be premature then.
@@ -376,7 +373,6 @@ static void sugov_update_single_perf(struct update_util_data *hook, u64 time,
unsigned int flags)
{
struct sugov_cpu *sg_cpu = container_of(hook, struct sugov_cpu, update_util);
- struct sugov_policy *sg_policy = sg_cpu->sg_policy;
unsigned long prev_util = sg_cpu->util;
/*
@@ -403,8 +399,7 @@ static void sugov_update_single_perf(struct update_util_data *hook, u64 time,
sg_cpu->util = prev_util;
cpufreq_driver_adjust_perf(sg_cpu->cpu, map_util_perf(sg_cpu->bw_dl),
- map_util_perf(sg_cpu->util),
- sg_policy->max);
+ map_util_perf(sg_cpu->util), sg_cpu->max);
sg_cpu->sg_policy->last_freq_update_time = time;
}
@@ -413,19 +408,25 @@ static unsigned int sugov_next_freq_shared(struct sugov_cpu *sg_cpu, u64 time)
{
struct sugov_policy *sg_policy = sg_cpu->sg_policy;
struct cpufreq_policy *policy = sg_policy->policy;
- unsigned long util = 0;
+ unsigned long util = 0, max = 1;
unsigned int j;
for_each_cpu(j, policy->cpus) {
struct sugov_cpu *j_sg_cpu = &per_cpu(sugov_cpu, j);
+ unsigned long j_util, j_max;
sugov_get_util(j_sg_cpu);
sugov_iowait_apply(j_sg_cpu, time);
+ j_util = j_sg_cpu->util;
+ j_max = j_sg_cpu->max;
- util = max(j_sg_cpu->util, util);
+ if (j_util * max > j_max * util) {
+ util = j_util;
+ max = j_max;
+ }
}
- return get_next_freq(sg_policy, util, sg_policy->max);
+ return get_next_freq(sg_policy, util, max);
}
static void
@@ -751,7 +752,7 @@ static int sugov_start(struct cpufreq_policy *policy)
{
struct sugov_policy *sg_policy = policy->governor_data;
void (*uu)(struct update_util_data *data, u64 time, unsigned int flags);
- unsigned int cpu = cpumask_first(policy->cpus);
+ unsigned int cpu;
sg_policy->freq_update_delay_ns = sg_policy->tunables->rate_limit_us * NSEC_PER_USEC;
sg_policy->last_freq_update_time = 0;
@@ -759,7 +760,6 @@ static int sugov_start(struct cpufreq_policy *policy)
sg_policy->work_in_progress = false;
sg_policy->limits_changed = false;
sg_policy->cached_raw_freq = 0;
- sg_policy->max = arch_scale_cpu_capacity(cpu);
sg_policy->need_freq_update = cpufreq_driver_test_flags(CPUFREQ_NEED_UPDATE_LIMITS);
diff --git a/kernel/sched/deadline.c b/kernel/sched/deadline.c
index 86dea6a05267..9ae8f41e3372 100644
--- a/kernel/sched/deadline.c
+++ b/kernel/sched/deadline.c
@@ -644,8 +644,8 @@ static inline bool need_pull_dl_task(struct rq *rq, struct task_struct *prev)
return rq->online && dl_task(prev);
}
-static DEFINE_PER_CPU(struct callback_head, dl_push_head);
-static DEFINE_PER_CPU(struct callback_head, dl_pull_head);
+static DEFINE_PER_CPU(struct balance_callback, dl_push_head);
+static DEFINE_PER_CPU(struct balance_callback, dl_pull_head);
static void push_dl_tasks(struct rq *);
static void pull_dl_task(struct rq *);
diff --git a/kernel/sched/rt.c b/kernel/sched/rt.c
index d869bcf898cc..ed2a47e4ddae 100644
--- a/kernel/sched/rt.c
+++ b/kernel/sched/rt.c
@@ -410,8 +410,8 @@ static inline int has_pushable_tasks(struct rq *rq)
return !plist_head_empty(&rq->rt.pushable_tasks);
}
-static DEFINE_PER_CPU(struct callback_head, rt_push_head);
-static DEFINE_PER_CPU(struct callback_head, rt_pull_head);
+static DEFINE_PER_CPU(struct balance_callback, rt_push_head);
+static DEFINE_PER_CPU(struct balance_callback, rt_pull_head);
static void push_rt_tasks(struct rq *);
static void pull_rt_task(struct rq *);
diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h
index 1644242ecd11..a4a20046e586 100644
--- a/kernel/sched/sched.h
+++ b/kernel/sched/sched.h
@@ -938,6 +938,12 @@ struct uclamp_rq {
DECLARE_STATIC_KEY_FALSE(sched_uclamp_used);
#endif /* CONFIG_UCLAMP_TASK */
+struct rq;
+struct balance_callback {
+ struct balance_callback *next;
+ void (*func)(struct rq *rq);
+};
+
/*
* This is the main, per-CPU runqueue data structure.
*
@@ -1036,7 +1042,7 @@ struct rq {
unsigned long cpu_capacity;
unsigned long cpu_capacity_orig;
- struct callback_head *balance_callback;
+ struct balance_callback *balance_callback;
unsigned char nohz_idle_balance;
unsigned char idle_balance;
@@ -1182,6 +1188,14 @@ static inline bool is_migration_disabled(struct task_struct *p)
#endif
}
+DECLARE_PER_CPU_SHARED_ALIGNED(struct rq, runqueues);
+
+#define cpu_rq(cpu) (&per_cpu(runqueues, (cpu)))
+#define this_rq() this_cpu_ptr(&runqueues)
+#define task_rq(p) cpu_rq(task_cpu(p))
+#define cpu_curr(cpu) (cpu_rq(cpu)->curr)
+#define raw_rq() raw_cpu_ptr(&runqueues)
+
struct sched_group;
#ifdef CONFIG_SCHED_CORE
static inline struct cpumask *sched_group_span(struct sched_group *sg);
@@ -1269,7 +1283,7 @@ static inline bool sched_group_cookie_match(struct rq *rq,
return true;
for_each_cpu_and(cpu, sched_group_span(group), p->cpus_ptr) {
- if (sched_core_cookie_match(rq, p))
+ if (sched_core_cookie_match(cpu_rq(cpu), p))
return true;
}
return false;
@@ -1384,14 +1398,6 @@ static inline void update_idle_core(struct rq *rq)
static inline void update_idle_core(struct rq *rq) { }
#endif
-DECLARE_PER_CPU_SHARED_ALIGNED(struct rq, runqueues);
-
-#define cpu_rq(cpu) (&per_cpu(runqueues, (cpu)))
-#define this_rq() this_cpu_ptr(&runqueues)
-#define task_rq(p) cpu_rq(task_cpu(p))
-#define cpu_curr(cpu) (cpu_rq(cpu)->curr)
-#define raw_rq() raw_cpu_ptr(&runqueues)
-
#ifdef CONFIG_FAIR_GROUP_SCHED
static inline struct task_struct *task_of(struct sched_entity *se)
{
@@ -1544,7 +1550,7 @@ struct rq_flags {
#endif
};
-extern struct callback_head balance_push_callback;
+extern struct balance_callback balance_push_callback;
/*
* Lockdep annotation that avoids accidental unlocks; it's like a
@@ -1724,7 +1730,7 @@ init_numa_balancing(unsigned long clone_flags, struct task_struct *p)
static inline void
queue_balance_callback(struct rq *rq,
- struct callback_head *head,
+ struct balance_callback *head,
void (*func)(struct rq *rq))
{
lockdep_assert_rq_held(rq);
@@ -1737,7 +1743,7 @@ queue_balance_callback(struct rq *rq,
if (unlikely(head->next || rq->balance_callback == &balance_push_callback))
return;
- head->func = (void (*)(struct callback_head *))func;
+ head->func = func;
head->next = rq->balance_callback;
rq->balance_callback = head;
}
diff --git a/kernel/sysctl.c b/kernel/sysctl.c
index 188c305aeb8b..c6d9dec11b74 100644
--- a/kernel/sysctl.c
+++ b/kernel/sysctl.c
@@ -267,13 +267,14 @@ int proc_dostring(struct ctl_table *table, int write,
ppos);
}
-static size_t proc_skip_spaces(char **buf)
+static void proc_skip_spaces(char **buf, size_t *size)
{
- size_t ret;
- char *tmp = skip_spaces(*buf);
- ret = tmp - *buf;
- *buf = tmp;
- return ret;
+ while (*size) {
+ if (!isspace(**buf))
+ break;
+ (*size)--;
+ (*buf)++;
+ }
}
static void proc_skip_char(char **buf, size_t *size, const char v)
@@ -342,13 +343,12 @@ static int proc_get_long(char **buf, size_t *size,
unsigned long *val, bool *neg,
const char *perm_tr, unsigned perm_tr_len, char *tr)
{
- int len;
char *p, tmp[TMPBUFLEN];
+ ssize_t len = *size;
- if (!*size)
+ if (len <= 0)
return -EINVAL;
- len = *size;
if (len > TMPBUFLEN - 1)
len = TMPBUFLEN - 1;
@@ -521,7 +521,7 @@ static int __do_proc_dointvec(void *tbl_data, struct ctl_table *table,
bool neg;
if (write) {
- left -= proc_skip_spaces(&p);
+ proc_skip_spaces(&p, &left);
if (!left)
break;
@@ -548,7 +548,7 @@ static int __do_proc_dointvec(void *tbl_data, struct ctl_table *table,
if (!write && !first && left && !err)
proc_put_char(&buffer, &left, '\n');
if (write && !err && left)
- left -= proc_skip_spaces(&p);
+ proc_skip_spaces(&p, &left);
if (write && first)
return err ? : -EINVAL;
*lenp -= left;
@@ -590,7 +590,7 @@ static int do_proc_douintvec_w(unsigned int *tbl_data,
if (left > PAGE_SIZE - 1)
left = PAGE_SIZE - 1;
- left -= proc_skip_spaces(&p);
+ proc_skip_spaces(&p, &left);
if (!left) {
err = -EINVAL;
goto out_free;
@@ -610,7 +610,7 @@ static int do_proc_douintvec_w(unsigned int *tbl_data,
}
if (!err && left)
- left -= proc_skip_spaces(&p);
+ proc_skip_spaces(&p, &left);
out_free:
if (err)
@@ -1075,7 +1075,7 @@ static int __do_proc_doulongvec_minmax(void *data, struct ctl_table *table,
if (write) {
bool neg;
- left -= proc_skip_spaces(&p);
+ proc_skip_spaces(&p, &left);
if (!left)
break;
@@ -1104,7 +1104,7 @@ static int __do_proc_doulongvec_minmax(void *data, struct ctl_table *table,
if (!write && !first && left && !err)
proc_put_char(&buffer, &left, '\n');
if (write && !err)
- left -= proc_skip_spaces(&p);
+ proc_skip_spaces(&p, &left);
if (write && first)
return err ? : -EINVAL;
*lenp -= left;
diff --git a/kernel/trace/blktrace.c b/kernel/trace/blktrace.c
index 7f5eb295fe19..a995ea1ef849 100644
--- a/kernel/trace/blktrace.c
+++ b/kernel/trace/blktrace.c
@@ -346,8 +346,40 @@ static void put_probe_ref(void)
mutex_unlock(&blk_probe_mutex);
}
+static int blk_trace_start(struct blk_trace *bt)
+{
+ if (bt->trace_state != Blktrace_setup &&
+ bt->trace_state != Blktrace_stopped)
+ return -EINVAL;
+
+ blktrace_seq++;
+ smp_mb();
+ bt->trace_state = Blktrace_running;
+ raw_spin_lock_irq(&running_trace_lock);
+ list_add(&bt->running_list, &running_trace_list);
+ raw_spin_unlock_irq(&running_trace_lock);
+ trace_note_time(bt);
+
+ return 0;
+}
+
+static int blk_trace_stop(struct blk_trace *bt)
+{
+ if (bt->trace_state != Blktrace_running)
+ return -EINVAL;
+
+ bt->trace_state = Blktrace_stopped;
+ raw_spin_lock_irq(&running_trace_lock);
+ list_del_init(&bt->running_list);
+ raw_spin_unlock_irq(&running_trace_lock);
+ relay_flush(bt->rchan);
+
+ return 0;
+}
+
static void blk_trace_cleanup(struct request_queue *q, struct blk_trace *bt)
{
+ blk_trace_stop(bt);
synchronize_rcu();
blk_trace_free(q, bt);
put_probe_ref();
@@ -362,8 +394,7 @@ static int __blk_trace_remove(struct request_queue *q)
if (!bt)
return -EINVAL;
- if (bt->trace_state != Blktrace_running)
- blk_trace_cleanup(q, bt);
+ blk_trace_cleanup(q, bt);
return 0;
}
@@ -658,7 +689,6 @@ static int compat_blk_trace_setup(struct request_queue *q, char *name,
static int __blk_trace_startstop(struct request_queue *q, int start)
{
- int ret;
struct blk_trace *bt;
bt = rcu_dereference_protected(q->blk_trace,
@@ -666,36 +696,10 @@ static int __blk_trace_startstop(struct request_queue *q, int start)
if (bt == NULL)
return -EINVAL;
- /*
- * For starting a trace, we can transition from a setup or stopped
- * trace. For stopping a trace, the state must be running
- */
- ret = -EINVAL;
- if (start) {
- if (bt->trace_state == Blktrace_setup ||
- bt->trace_state == Blktrace_stopped) {
- blktrace_seq++;
- smp_mb();
- bt->trace_state = Blktrace_running;
- raw_spin_lock_irq(&running_trace_lock);
- list_add(&bt->running_list, &running_trace_list);
- raw_spin_unlock_irq(&running_trace_lock);
-
- trace_note_time(bt);
- ret = 0;
- }
- } else {
- if (bt->trace_state == Blktrace_running) {
- bt->trace_state = Blktrace_stopped;
- raw_spin_lock_irq(&running_trace_lock);
- list_del_init(&bt->running_list);
- raw_spin_unlock_irq(&running_trace_lock);
- relay_flush(bt->rchan);
- ret = 0;
- }
- }
-
- return ret;
+ if (start)
+ return blk_trace_start(bt);
+ else
+ return blk_trace_stop(bt);
}
int blk_trace_startstop(struct request_queue *q, int start)
@@ -772,10 +776,8 @@ int blk_trace_ioctl(struct block_device *bdev, unsigned cmd, char __user *arg)
void blk_trace_shutdown(struct request_queue *q)
{
if (rcu_dereference_protected(q->blk_trace,
- lockdep_is_held(&q->debugfs_mutex))) {
- __blk_trace_startstop(q, 0);
+ lockdep_is_held(&q->debugfs_mutex)))
__blk_trace_remove(q);
- }
}
#ifdef CONFIG_BLK_CGROUP
@@ -1614,13 +1616,7 @@ static int blk_trace_remove_queue(struct request_queue *q)
if (bt == NULL)
return -EINVAL;
- if (bt->trace_state == Blktrace_running) {
- bt->trace_state = Blktrace_stopped;
- raw_spin_lock_irq(&running_trace_lock);
- list_del_init(&bt->running_list);
- raw_spin_unlock_irq(&running_trace_lock);
- relay_flush(bt->rchan);
- }
+ blk_trace_stop(bt);
put_probe_ref();
synchronize_rcu();
diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c
index 49fb9ec8366d..1ed08967fb97 100644
--- a/kernel/trace/bpf_trace.c
+++ b/kernel/trace/bpf_trace.c
@@ -687,6 +687,7 @@ BPF_CALL_5(bpf_perf_event_output, struct pt_regs *, regs, struct bpf_map *, map,
perf_sample_data_init(sd, 0, 0);
sd->raw = &raw;
+ sd->sample_flags |= PERF_SAMPLE_RAW;
err = __bpf_perf_event_output(regs, map, flags, sd);
@@ -745,6 +746,7 @@ u64 bpf_event_output(struct bpf_map *map, u64 flags, void *meta, u64 meta_size,
perf_fetch_caller_regs(regs);
perf_sample_data_init(sd, 0, 0);
sd->raw = &raw;
+ sd->sample_flags |= PERF_SAMPLE_RAW;
ret = __bpf_perf_event_output(regs, map, flags, sd);
out:
diff --git a/kernel/trace/fprobe.c b/kernel/trace/fprobe.c
index aac63ca9c3d1..e8143e368074 100644
--- a/kernel/trace/fprobe.c
+++ b/kernel/trace/fprobe.c
@@ -141,6 +141,8 @@ static int fprobe_init_rethook(struct fprobe *fp, int num)
return -E2BIG;
fp->rethook = rethook_alloc((void *)fp, fprobe_exit_handler);
+ if (!fp->rethook)
+ return -ENOMEM;
for (i = 0; i < size; i++) {
struct fprobe_rethook_node *node;
@@ -301,7 +303,8 @@ int unregister_fprobe(struct fprobe *fp)
{
int ret;
- if (!fp || fp->ops.func != fprobe_handler)
+ if (!fp || (fp->ops.saved_func != fprobe_handler &&
+ fp->ops.saved_func != fprobe_kprobe_handler))
return -EINVAL;
/*
diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index fbf2543111c0..33236241f236 100644
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -1289,6 +1289,7 @@ static int ftrace_add_mod(struct trace_array *tr,
if (!ftrace_mod)
return -ENOMEM;
+ INIT_LIST_HEAD(&ftrace_mod->list);
ftrace_mod->func = kstrdup(func, GFP_KERNEL);
ftrace_mod->module = kstrdup(module, GFP_KERNEL);
ftrace_mod->enable = enable;
@@ -3028,18 +3029,8 @@ int ftrace_shutdown(struct ftrace_ops *ops, int command)
command |= FTRACE_UPDATE_TRACE_FUNC;
}
- if (!command || !ftrace_enabled) {
- /*
- * If these are dynamic or per_cpu ops, they still
- * need their data freed. Since, function tracing is
- * not currently active, we can just free them
- * without synchronizing all CPUs.
- */
- if (ops->flags & FTRACE_OPS_FL_DYNAMIC)
- goto free_ops;
-
- return 0;
- }
+ if (!command || !ftrace_enabled)
+ goto out;
/*
* If the ops uses a trampoline, then it needs to be
@@ -3076,6 +3067,7 @@ int ftrace_shutdown(struct ftrace_ops *ops, int command)
removed_ops = NULL;
ops->flags &= ~FTRACE_OPS_FL_REMOVING;
+out:
/*
* Dynamic ops may be freed, we must make sure that all
* callers are done before leaving this function.
@@ -3103,7 +3095,6 @@ int ftrace_shutdown(struct ftrace_ops *ops, int command)
if (IS_ENABLED(CONFIG_PREEMPTION))
synchronize_rcu_tasks();
- free_ops:
ftrace_trampoline_free(ops);
}
@@ -3200,7 +3191,7 @@ static int ftrace_allocate_records(struct ftrace_page *pg, int count)
/* if we can't allocate this size, try something smaller */
if (!order)
return -ENOMEM;
- order >>= 1;
+ order--;
goto again;
}
@@ -7401,7 +7392,7 @@ void __init ftrace_init(void)
}
pr_info("ftrace: allocating %ld entries in %ld pages\n",
- count, count / ENTRIES_PER_PAGE + 1);
+ count, DIV_ROUND_UP(count, ENTRIES_PER_PAGE));
ret = ftrace_process_locs(NULL,
__start_mcount_loc,
diff --git a/kernel/trace/kprobe_event_gen_test.c b/kernel/trace/kprobe_event_gen_test.c
index 80e04a1e1977..c736487fc0e4 100644
--- a/kernel/trace/kprobe_event_gen_test.c
+++ b/kernel/trace/kprobe_event_gen_test.c
@@ -73,6 +73,10 @@ static struct trace_event_file *gen_kretprobe_test;
#define KPROBE_GEN_TEST_ARG3 NULL
#endif
+static bool trace_event_file_is_valid(struct trace_event_file *input)
+{
+ return input && !IS_ERR(input);
+}
/*
* Test to make sure we can create a kprobe event, then add more
@@ -100,20 +104,20 @@ static int __init test_gen_kprobe_cmd(void)
KPROBE_GEN_TEST_FUNC,
KPROBE_GEN_TEST_ARG0, KPROBE_GEN_TEST_ARG1);
if (ret)
- goto free;
+ goto out;
/* Use kprobe_event_add_fields to add the rest of the fields */
ret = kprobe_event_add_fields(&cmd, KPROBE_GEN_TEST_ARG2, KPROBE_GEN_TEST_ARG3);
if (ret)
- goto free;
+ goto out;
/*
* This actually creates the event.
*/
ret = kprobe_event_gen_cmd_end(&cmd);
if (ret)
- goto free;
+ goto out;
/*
* Now get the gen_kprobe_test event file. We need to prevent
@@ -136,13 +140,13 @@ static int __init test_gen_kprobe_cmd(void)
goto delete;
}
out:
+ kfree(buf);
return ret;
delete:
+ if (trace_event_file_is_valid(gen_kprobe_test))
+ gen_kprobe_test = NULL;
/* We got an error after creating the event, delete it */
ret = kprobe_event_delete("gen_kprobe_test");
- free:
- kfree(buf);
-
goto out;
}
@@ -170,14 +174,14 @@ static int __init test_gen_kretprobe_cmd(void)
KPROBE_GEN_TEST_FUNC,
"$retval");
if (ret)
- goto free;
+ goto out;
/*
* This actually creates the event.
*/
ret = kretprobe_event_gen_cmd_end(&cmd);
if (ret)
- goto free;
+ goto out;
/*
* Now get the gen_kretprobe_test event file. We need to
@@ -201,13 +205,13 @@ static int __init test_gen_kretprobe_cmd(void)
goto delete;
}
out:
+ kfree(buf);
return ret;
delete:
+ if (trace_event_file_is_valid(gen_kretprobe_test))
+ gen_kretprobe_test = NULL;
/* We got an error after creating the event, delete it */
ret = kprobe_event_delete("gen_kretprobe_test");
- free:
- kfree(buf);
-
goto out;
}
@@ -221,10 +225,12 @@ static int __init kprobe_event_gen_test_init(void)
ret = test_gen_kretprobe_cmd();
if (ret) {
- WARN_ON(trace_array_set_clr_event(gen_kretprobe_test->tr,
- "kprobes",
- "gen_kretprobe_test", false));
- trace_put_event_file(gen_kretprobe_test);
+ if (trace_event_file_is_valid(gen_kretprobe_test)) {
+ WARN_ON(trace_array_set_clr_event(gen_kretprobe_test->tr,
+ "kprobes",
+ "gen_kretprobe_test", false));
+ trace_put_event_file(gen_kretprobe_test);
+ }
WARN_ON(kprobe_event_delete("gen_kretprobe_test"));
}
@@ -233,24 +239,30 @@ static int __init kprobe_event_gen_test_init(void)
static void __exit kprobe_event_gen_test_exit(void)
{
- /* Disable the event or you can't remove it */
- WARN_ON(trace_array_set_clr_event(gen_kprobe_test->tr,
- "kprobes",
- "gen_kprobe_test", false));
+ if (trace_event_file_is_valid(gen_kprobe_test)) {
+ /* Disable the event or you can't remove it */
+ WARN_ON(trace_array_set_clr_event(gen_kprobe_test->tr,
+ "kprobes",
+ "gen_kprobe_test", false));
+
+ /* Now give the file and instance back */
+ trace_put_event_file(gen_kprobe_test);
+ }
- /* Now give the file and instance back */
- trace_put_event_file(gen_kprobe_test);
/* Now unregister and free the event */
WARN_ON(kprobe_event_delete("gen_kprobe_test"));
- /* Disable the event or you can't remove it */
- WARN_ON(trace_array_set_clr_event(gen_kretprobe_test->tr,
- "kprobes",
- "gen_kretprobe_test", false));
+ if (trace_event_file_is_valid(gen_kretprobe_test)) {
+ /* Disable the event or you can't remove it */
+ WARN_ON(trace_array_set_clr_event(gen_kretprobe_test->tr,
+ "kprobes",
+ "gen_kretprobe_test", false));
+
+ /* Now give the file and instance back */
+ trace_put_event_file(gen_kretprobe_test);
+ }
- /* Now give the file and instance back */
- trace_put_event_file(gen_kretprobe_test);
/* Now unregister and free the event */
WARN_ON(kprobe_event_delete("gen_kretprobe_test"));
diff --git a/kernel/trace/rethook.c b/kernel/trace/rethook.c
index c69d82273ce7..32c3dfdb4d6a 100644
--- a/kernel/trace/rethook.c
+++ b/kernel/trace/rethook.c
@@ -83,8 +83,10 @@ struct rethook *rethook_alloc(void *data, rethook_handler_t handler)
{
struct rethook *rh = kzalloc(sizeof(struct rethook), GFP_KERNEL);
- if (!rh || !handler)
+ if (!rh || !handler) {
+ kfree(rh);
return NULL;
+ }
rh->data = data;
rh->handler = handler;
diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c
index 199759c73519..b21bf14bae9b 100644
--- a/kernel/trace/ring_buffer.c
+++ b/kernel/trace/ring_buffer.c
@@ -519,6 +519,7 @@ struct ring_buffer_per_cpu {
local_t committing;
local_t commits;
local_t pages_touched;
+ local_t pages_lost;
local_t pages_read;
long last_pages_touch;
size_t shortest_full;
@@ -894,10 +895,18 @@ size_t ring_buffer_nr_pages(struct trace_buffer *buffer, int cpu)
size_t ring_buffer_nr_dirty_pages(struct trace_buffer *buffer, int cpu)
{
size_t read;
+ size_t lost;
size_t cnt;
read = local_read(&buffer->buffers[cpu]->pages_read);
+ lost = local_read(&buffer->buffers[cpu]->pages_lost);
cnt = local_read(&buffer->buffers[cpu]->pages_touched);
+
+ if (WARN_ON_ONCE(cnt < lost))
+ return 0;
+
+ cnt -= lost;
+
/* The reader can read an empty page, but not more than that */
if (cnt < read) {
WARN_ON_ONCE(read > cnt + 1);
@@ -907,6 +916,21 @@ size_t ring_buffer_nr_dirty_pages(struct trace_buffer *buffer, int cpu)
return cnt - read;
}
+static __always_inline bool full_hit(struct trace_buffer *buffer, int cpu, int full)
+{
+ struct ring_buffer_per_cpu *cpu_buffer = buffer->buffers[cpu];
+ size_t nr_pages;
+ size_t dirty;
+
+ nr_pages = cpu_buffer->nr_pages;
+ if (!nr_pages || !full)
+ return true;
+
+ dirty = ring_buffer_nr_dirty_pages(buffer, cpu);
+
+ return (dirty * 100) > (full * nr_pages);
+}
+
/*
* rb_wake_up_waiters - wake up tasks waiting for ring buffer input
*
@@ -937,6 +961,9 @@ void ring_buffer_wake_waiters(struct trace_buffer *buffer, int cpu)
struct ring_buffer_per_cpu *cpu_buffer;
struct rb_irq_work *rbwork;
+ if (!buffer)
+ return;
+
if (cpu == RING_BUFFER_ALL_CPUS) {
/* Wake up individual ones too. One level recursion */
@@ -945,7 +972,15 @@ void ring_buffer_wake_waiters(struct trace_buffer *buffer, int cpu)
rbwork = &buffer->irq_work;
} else {
+ if (WARN_ON_ONCE(!buffer->buffers))
+ return;
+ if (WARN_ON_ONCE(cpu >= nr_cpu_ids))
+ return;
+
cpu_buffer = buffer->buffers[cpu];
+ /* The CPU buffer may not have been initialized yet */
+ if (!cpu_buffer)
+ return;
rbwork = &cpu_buffer->irq_work;
}
@@ -1035,22 +1070,20 @@ int ring_buffer_wait(struct trace_buffer *buffer, int cpu, int full)
!ring_buffer_empty_cpu(buffer, cpu)) {
unsigned long flags;
bool pagebusy;
- size_t nr_pages;
- size_t dirty;
+ bool done;
if (!full)
break;
raw_spin_lock_irqsave(&cpu_buffer->reader_lock, flags);
pagebusy = cpu_buffer->reader_page == cpu_buffer->commit_page;
- nr_pages = cpu_buffer->nr_pages;
- dirty = ring_buffer_nr_dirty_pages(buffer, cpu);
+ done = !pagebusy && full_hit(buffer, cpu, full);
+
if (!cpu_buffer->shortest_full ||
cpu_buffer->shortest_full > full)
cpu_buffer->shortest_full = full;
raw_spin_unlock_irqrestore(&cpu_buffer->reader_lock, flags);
- if (!pagebusy &&
- (!nr_pages || (dirty * 100) > full * nr_pages))
+ if (done)
break;
}
@@ -1076,6 +1109,7 @@ int ring_buffer_wait(struct trace_buffer *buffer, int cpu, int full)
* @cpu: the cpu buffer to wait on
* @filp: the file descriptor
* @poll_table: The poll descriptor
+ * @full: wait until the percentage of pages are available, if @cpu != RING_BUFFER_ALL_CPUS
*
* If @cpu == RING_BUFFER_ALL_CPUS then the task will wake up as soon
* as data is added to any of the @buffer's cpu buffers. Otherwise
@@ -1085,14 +1119,15 @@ int ring_buffer_wait(struct trace_buffer *buffer, int cpu, int full)
* zero otherwise.
*/
__poll_t ring_buffer_poll_wait(struct trace_buffer *buffer, int cpu,
- struct file *filp, poll_table *poll_table)
+ struct file *filp, poll_table *poll_table, int full)
{
struct ring_buffer_per_cpu *cpu_buffer;
struct rb_irq_work *work;
- if (cpu == RING_BUFFER_ALL_CPUS)
+ if (cpu == RING_BUFFER_ALL_CPUS) {
work = &buffer->irq_work;
- else {
+ full = 0;
+ } else {
if (!cpumask_test_cpu(cpu, buffer->cpumask))
return -EINVAL;
@@ -1100,8 +1135,14 @@ __poll_t ring_buffer_poll_wait(struct trace_buffer *buffer, int cpu,
work = &cpu_buffer->irq_work;
}
- poll_wait(filp, &work->waiters, poll_table);
- work->waiters_pending = true;
+ if (full) {
+ poll_wait(filp, &work->full_waiters, poll_table);
+ work->full_waiters_pending = true;
+ } else {
+ 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
@@ -1117,6 +1158,9 @@ __poll_t ring_buffer_poll_wait(struct trace_buffer *buffer, int cpu,
*/
smp_mb();
+ if (full)
+ return full_hit(buffer, cpu, full) ? EPOLLIN | EPOLLRDNORM : 0;
+
if ((cpu == RING_BUFFER_ALL_CPUS && !ring_buffer_empty(buffer)) ||
(cpu != RING_BUFFER_ALL_CPUS && !ring_buffer_empty_cpu(buffer, cpu)))
return EPOLLIN | EPOLLRDNORM;
@@ -1758,9 +1802,9 @@ static void rb_free_cpu_buffer(struct ring_buffer_per_cpu *cpu_buffer)
free_buffer_page(cpu_buffer->reader_page);
- rb_head_page_deactivate(cpu_buffer);
-
if (head) {
+ rb_head_page_deactivate(cpu_buffer);
+
list_for_each_entry_safe(bpage, tmp, head, list) {
list_del_init(&bpage->list);
free_buffer_page(bpage);
@@ -1996,6 +2040,7 @@ rb_remove_pages(struct ring_buffer_per_cpu *cpu_buffer, unsigned long nr_pages)
*/
local_add(page_entries, &cpu_buffer->overrun);
local_sub(BUF_PAGE_SIZE, &cpu_buffer->entries_bytes);
+ local_inc(&cpu_buffer->pages_lost);
}
/*
@@ -2480,6 +2525,7 @@ rb_handle_head_page(struct ring_buffer_per_cpu *cpu_buffer,
*/
local_add(entries, &cpu_buffer->overrun);
local_sub(BUF_PAGE_SIZE, &cpu_buffer->entries_bytes);
+ local_inc(&cpu_buffer->pages_lost);
/*
* The entries will be zeroed out when we move the
@@ -3144,10 +3190,6 @@ static void rb_commit(struct ring_buffer_per_cpu *cpu_buffer,
static __always_inline void
rb_wakeups(struct trace_buffer *buffer, struct ring_buffer_per_cpu *cpu_buffer)
{
- size_t nr_pages;
- size_t dirty;
- size_t full;
-
if (buffer->irq_work.waiters_pending) {
buffer->irq_work.waiters_pending = false;
/* irq_work_queue() supplies it's own memory barriers */
@@ -3171,10 +3213,7 @@ rb_wakeups(struct trace_buffer *buffer, struct ring_buffer_per_cpu *cpu_buffer)
cpu_buffer->last_pages_touch = local_read(&cpu_buffer->pages_touched);
- full = cpu_buffer->shortest_full;
- nr_pages = cpu_buffer->nr_pages;
- dirty = ring_buffer_nr_dirty_pages(buffer, cpu_buffer->cpu);
- if (full && nr_pages && (dirty * 100) <= full * nr_pages)
+ if (!full_hit(buffer, cpu_buffer->cpu, cpu_buffer->shortest_full))
return;
cpu_buffer->irq_work.wakeup_full = true;
@@ -5237,6 +5276,7 @@ rb_reset_cpu(struct ring_buffer_per_cpu *cpu_buffer)
local_set(&cpu_buffer->committing, 0);
local_set(&cpu_buffer->commits, 0);
local_set(&cpu_buffer->pages_touched, 0);
+ local_set(&cpu_buffer->pages_lost, 0);
local_set(&cpu_buffer->pages_read, 0);
cpu_buffer->last_pages_touch = 0;
cpu_buffer->shortest_full = 0;
diff --git a/kernel/trace/synth_event_gen_test.c b/kernel/trace/synth_event_gen_test.c
index 0b15e975d2c2..8d77526892f4 100644
--- a/kernel/trace/synth_event_gen_test.c
+++ b/kernel/trace/synth_event_gen_test.c
@@ -120,15 +120,13 @@ static int __init test_gen_synth_cmd(void)
/* Now generate a gen_synth_test event */
ret = synth_event_trace_array(gen_synth_test, vals, ARRAY_SIZE(vals));
- out:
+ free:
+ kfree(buf);
return ret;
delete:
/* We got an error after creating the event, delete it */
synth_event_delete("gen_synth_test");
- free:
- kfree(buf);
-
- goto out;
+ goto free;
}
/*
@@ -227,15 +225,13 @@ static int __init test_empty_synth_event(void)
/* Now trace an empty_synth_test event */
ret = synth_event_trace_array(empty_synth_test, vals, ARRAY_SIZE(vals));
- out:
+ free:
+ kfree(buf);
return ret;
delete:
/* We got an error after creating the event, delete it */
synth_event_delete("empty_synth_test");
- free:
- kfree(buf);
-
- goto out;
+ goto free;
}
static struct synth_field_desc create_synth_test_fields[] = {
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 47a44b055a1d..5cfc95a52bc3 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -2180,10 +2180,12 @@ void tracing_reset_online_cpus(struct array_buffer *buf)
}
/* Must have trace_types_lock held */
-void tracing_reset_all_online_cpus(void)
+void tracing_reset_all_online_cpus_unlocked(void)
{
struct trace_array *tr;
+ lockdep_assert_held(&trace_types_lock);
+
list_for_each_entry(tr, &ftrace_trace_arrays, list) {
if (!tr->clear_trace)
continue;
@@ -2195,6 +2197,13 @@ void tracing_reset_all_online_cpus(void)
}
}
+void tracing_reset_all_online_cpus(void)
+{
+ mutex_lock(&trace_types_lock);
+ tracing_reset_all_online_cpus_unlocked();
+ mutex_unlock(&trace_types_lock);
+}
+
/*
* The tgid_map array maps from pid to tgid; i.e. the value stored at index i
* is the tgid last observed corresponding to pid=i.
@@ -6657,6 +6666,7 @@ static int tracing_release_pipe(struct inode *inode, struct file *file)
mutex_unlock(&trace_types_lock);
free_cpumask_var(iter->started);
+ kfree(iter->fmt);
mutex_destroy(&iter->mutex);
kfree(iter);
@@ -6681,7 +6691,7 @@ trace_poll(struct trace_iterator *iter, struct file *filp, poll_table *poll_tabl
return EPOLLIN | EPOLLRDNORM;
else
return ring_buffer_poll_wait(iter->array_buffer->buffer, iter->cpu_file,
- filp, poll_table);
+ filp, poll_table, iter->tr->buffer_percent);
}
static __poll_t
@@ -7802,6 +7812,7 @@ static struct tracing_log_err *get_tracing_log_err(struct trace_array *tr,
int len)
{
struct tracing_log_err *err;
+ char *cmd;
if (tr->n_err_log_entries < TRACING_LOG_ERRS_MAX) {
err = alloc_tracing_log_err(len);
@@ -7810,12 +7821,12 @@ static struct tracing_log_err *get_tracing_log_err(struct trace_array *tr,
return err;
}
-
+ cmd = kzalloc(len, GFP_KERNEL);
+ if (!cmd)
+ return ERR_PTR(-ENOMEM);
err = list_first_entry(&tr->err_log, struct tracing_log_err, list);
kfree(err->cmd);
- err->cmd = kzalloc(len, GFP_KERNEL);
- if (!err->cmd)
- return ERR_PTR(-ENOMEM);
+ err->cmd = cmd;
list_del(&err->list);
return err;
diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h
index 54ee5711c729..d42e24507152 100644
--- a/kernel/trace/trace.h
+++ b/kernel/trace/trace.h
@@ -580,6 +580,7 @@ int tracing_is_enabled(void);
void tracing_reset_online_cpus(struct array_buffer *buf);
void tracing_reset_current(int cpu);
void tracing_reset_all_online_cpus(void);
+void tracing_reset_all_online_cpus_unlocked(void);
int tracing_open_generic(struct inode *inode, struct file *filp);
int tracing_open_generic_tr(struct inode *inode, struct file *filp);
bool tracing_is_disabled(void);
diff --git a/kernel/trace/trace_dynevent.c b/kernel/trace/trace_dynevent.c
index 154996684fb5..4376887e0d8a 100644
--- a/kernel/trace/trace_dynevent.c
+++ b/kernel/trace/trace_dynevent.c
@@ -118,6 +118,7 @@ int dyn_event_release(const char *raw_command, struct dyn_event_operations *type
if (ret)
break;
}
+ tracing_reset_all_online_cpus();
mutex_unlock(&event_mutex);
out:
argv_free(argv);
@@ -214,6 +215,7 @@ int dyn_events_release_all(struct dyn_event_operations *type)
break;
}
out:
+ tracing_reset_all_online_cpus();
mutex_unlock(&event_mutex);
return ret;
diff --git a/kernel/trace/trace_eprobe.c b/kernel/trace/trace_eprobe.c
index 5dd0617e5df6..352b65e2b910 100644
--- a/kernel/trace/trace_eprobe.c
+++ b/kernel/trace/trace_eprobe.c
@@ -52,6 +52,7 @@ static void trace_event_probe_cleanup(struct trace_eprobe *ep)
kfree(ep->event_system);
if (ep->event)
trace_event_put_ref(ep->event);
+ kfree(ep->filter_str);
kfree(ep);
}
@@ -563,6 +564,9 @@ static void eprobe_trigger_func(struct event_trigger_data *data,
{
struct eprobe_data *edata = data->private_data;
+ if (unlikely(!rec))
+ return;
+
__eprobe_trace_func(edata, rec);
}
@@ -642,7 +646,7 @@ new_eprobe_trigger(struct trace_eprobe *ep, struct trace_event_file *file)
INIT_LIST_HEAD(&trigger->list);
if (ep->filter_str) {
- ret = create_event_filter(file->tr, file->event_call,
+ ret = create_event_filter(file->tr, ep->event,
ep->filter_str, false, &filter);
if (ret)
goto error;
@@ -900,7 +904,7 @@ static int trace_eprobe_tp_update_arg(struct trace_eprobe *ep, const char *argv[
static int trace_eprobe_parse_filter(struct trace_eprobe *ep, int argc, const char *argv[])
{
- struct event_filter *dummy;
+ struct event_filter *dummy = NULL;
int i, ret, len = 0;
char *p;
diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c
index 0356cae0cf74..f71ea6e79b3c 100644
--- a/kernel/trace/trace_events.c
+++ b/kernel/trace/trace_events.c
@@ -2880,7 +2880,10 @@ static int probe_remove_event_call(struct trace_event_call *call)
* TRACE_REG_UNREGISTER.
*/
if (file->flags & EVENT_FILE_FL_ENABLED)
- return -EBUSY;
+ goto busy;
+
+ if (file->flags & EVENT_FILE_FL_WAS_ENABLED)
+ tr->clear_trace = true;
/*
* The do_for_each_event_file_safe() is
* a double loop. After finding the call for this
@@ -2893,6 +2896,12 @@ static int probe_remove_event_call(struct trace_event_call *call)
__trace_remove_event_call(call);
return 0;
+ busy:
+ /* No need to clear the trace now */
+ list_for_each_entry(tr, &ftrace_trace_arrays, list) {
+ tr->clear_trace = false;
+ }
+ return -EBUSY;
}
/* Remove an event_call */
@@ -2972,7 +2981,7 @@ static void trace_module_remove_events(struct module *mod)
* over from this module may be passed to the new module events and
* unexpected results may occur.
*/
- tracing_reset_all_online_cpus();
+ tracing_reset_all_online_cpus_unlocked();
}
static int trace_module_notify(struct notifier_block *self,
diff --git a/kernel/trace/trace_events_hist.c b/kernel/trace/trace_events_hist.c
index 48465f7e97b4..1c82478e8dff 100644
--- a/kernel/trace/trace_events_hist.c
+++ b/kernel/trace/trace_events_hist.c
@@ -983,7 +983,7 @@ static struct hist_field *find_any_var_ref(struct hist_trigger_data *hist_data,
* A trigger can define one or more variables. If any one of them is
* currently referenced by any other trigger, this function will
* determine that.
-
+ *
* Typically used to determine whether or not a trigger can be removed
* - if there are any references to a trigger's variables, it cannot.
*
@@ -3226,7 +3226,7 @@ static struct field_var *create_field_var(struct hist_trigger_data *hist_data,
* events. However, for convenience, users are allowed to directly
* specify an event field in an action, which will be automatically
* converted into a variable on their behalf.
-
+ *
* This function creates a field variable with the name var_name on
* the hist trigger currently being defined on the target event. If
* subsys_name and event_name are specified, this function simply
@@ -5143,6 +5143,9 @@ static void event_hist_trigger(struct event_trigger_data *data,
void *key = NULL;
unsigned int i;
+ if (unlikely(!rbe))
+ return;
+
memset(compound_key, 0, hist_data->key_size);
for_each_hist_key_field(i, hist_data) {
diff --git a/kernel/trace/trace_events_synth.c b/kernel/trace/trace_events_synth.c
index e310052dc83c..c3b582d19b62 100644
--- a/kernel/trace/trace_events_synth.c
+++ b/kernel/trace/trace_events_synth.c
@@ -828,10 +828,9 @@ static int register_synth_event(struct synth_event *event)
}
ret = set_synth_event_print_fmt(call);
- if (ret < 0) {
+ /* unregister_trace_event() will be called inside */
+ if (ret < 0)
trace_remove_event_call(call);
- goto err;
- }
out:
return ret;
err:
@@ -1426,7 +1425,6 @@ int synth_event_delete(const char *event_name)
mutex_unlock(&event_mutex);
if (mod) {
- mutex_lock(&trace_types_lock);
/*
* It is safest to reset the ring buffer if the module
* being unloaded registered any events that were
@@ -1438,7 +1436,6 @@ int synth_event_delete(const char *event_name)
* occur.
*/
tracing_reset_all_online_cpus();
- mutex_unlock(&trace_types_lock);
}
return ret;
diff --git a/kernel/trace/trace_events_user.c b/kernel/trace/trace_events_user.c
index ae78c2d53c8a..539b08ae7020 100644
--- a/kernel/trace/trace_events_user.c
+++ b/kernel/trace/trace_events_user.c
@@ -1100,8 +1100,10 @@ static int user_event_create(const char *raw_command)
group = current_user_event_group();
- if (!group)
+ if (!group) {
+ kfree(name);
return -ENOENT;
+ }
mutex_lock(&group->reg_mutex);
diff --git a/kernel/trace/trace_osnoise.c b/kernel/trace/trace_osnoise.c
index 78d536d3ff3d..4300c5dc4e5d 100644
--- a/kernel/trace/trace_osnoise.c
+++ b/kernel/trace/trace_osnoise.c
@@ -917,7 +917,7 @@ void osnoise_trace_irq_entry(int id)
void osnoise_trace_irq_exit(int id, const char *desc)
{
struct osnoise_variables *osn_var = this_cpu_osn_var();
- int duration;
+ s64 duration;
if (!osn_var->sampling)
return;
@@ -1048,7 +1048,7 @@ static void trace_softirq_entry_callback(void *data, unsigned int vec_nr)
static void trace_softirq_exit_callback(void *data, unsigned int vec_nr)
{
struct osnoise_variables *osn_var = this_cpu_osn_var();
- int duration;
+ s64 duration;
if (!osn_var->sampling)
return;
@@ -1144,7 +1144,7 @@ thread_entry(struct osnoise_variables *osn_var, struct task_struct *t)
static void
thread_exit(struct osnoise_variables *osn_var, struct task_struct *t)
{
- int duration;
+ s64 duration;
if (!osn_var->sampling)
return;
diff --git a/kernel/trace/trace_syscalls.c b/kernel/trace/trace_syscalls.c
index b69e207012c9..942ddbdace4a 100644
--- a/kernel/trace/trace_syscalls.c
+++ b/kernel/trace/trace_syscalls.c
@@ -201,8 +201,6 @@ print_syscall_exit(struct trace_iterator *iter, int flags,
return trace_handle_return(s);
}
-extern char *__bad_type_size(void);
-
#define SYSCALL_FIELD(_type, _name) { \
.type = #_type, .name = #_name, \
.size = sizeof(_type), .align = __alignof__(_type), \
diff --git a/kernel/utsname_sysctl.c b/kernel/utsname_sysctl.c
index 064072c16e3d..f50398cb790d 100644
--- a/kernel/utsname_sysctl.c
+++ b/kernel/utsname_sysctl.c
@@ -74,6 +74,7 @@ static int proc_do_uts_string(struct ctl_table *table, int write,
static DEFINE_CTL_TABLE_POLL(hostname_poll);
static DEFINE_CTL_TABLE_POLL(domainname_poll);
+// Note: update 'enum uts_proc' to match any changes to this table
static struct ctl_table uts_kern_table[] = {
{
.procname = "arch",
diff --git a/kernel/workqueue.c b/kernel/workqueue.c
index 7cd5f5e7e0a1..07895deca271 100644
--- a/kernel/workqueue.c
+++ b/kernel/workqueue.c
@@ -1771,7 +1771,7 @@ bool queue_rcu_work(struct workqueue_struct *wq, struct rcu_work *rwork)
if (!test_and_set_bit(WORK_STRUCT_PENDING_BIT, work_data_bits(work))) {
rwork->wq = wq;
- call_rcu(&rwork->rcu, rcu_work_rcufn);
+ call_rcu_hurry(&rwork->rcu, rcu_work_rcufn);
return true;
}