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Diffstat (limited to 'kernel')
-rw-r--r--kernel/events/core.c20
-rw-r--r--kernel/futex/core.c12
-rw-r--r--kernel/sched/core.c2
-rw-r--r--kernel/sched/fair.c15
-rw-r--r--kernel/trace/ring_buffer.c4
-rw-r--r--kernel/trace/trace_events_hist.c6
-rw-r--r--kernel/trace/trace_fprobe.c7
7 files changed, 42 insertions, 24 deletions
diff --git a/kernel/events/core.c b/kernel/events/core.c
index 177e57c1a362..1fd347da9026 100644
--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -11773,7 +11773,8 @@ static enum hrtimer_restart perf_swevent_hrtimer(struct hrtimer *hrtimer)
event = container_of(hrtimer, struct perf_event, hw.hrtimer);
- if (event->state != PERF_EVENT_STATE_ACTIVE)
+ if (event->state != PERF_EVENT_STATE_ACTIVE ||
+ event->hw.state & PERF_HES_STOPPED)
return HRTIMER_NORESTART;
event->pmu->read(event);
@@ -11819,15 +11820,20 @@ static void perf_swevent_cancel_hrtimer(struct perf_event *event)
struct hw_perf_event *hwc = &event->hw;
/*
- * The throttle can be triggered in the hrtimer handler.
- * The HRTIMER_NORESTART should be used to stop the timer,
- * rather than hrtimer_cancel(). See perf_swevent_hrtimer()
+ * Careful: this function can be triggered in the hrtimer handler,
+ * for cpu-clock events, so hrtimer_cancel() would cause a
+ * deadlock.
+ *
+ * So use hrtimer_try_to_cancel() to try to stop the hrtimer,
+ * and the cpu-clock handler also sets the PERF_HES_STOPPED flag,
+ * which guarantees that perf_swevent_hrtimer() will stop the
+ * hrtimer once it sees the PERF_HES_STOPPED flag.
*/
if (is_sampling_event(event) && (hwc->interrupts != MAX_INTERRUPTS)) {
ktime_t remaining = hrtimer_get_remaining(&hwc->hrtimer);
local64_set(&hwc->period_left, ktime_to_ns(remaining));
- hrtimer_cancel(&hwc->hrtimer);
+ hrtimer_try_to_cancel(&hwc->hrtimer);
}
}
@@ -11871,12 +11877,14 @@ static void cpu_clock_event_update(struct perf_event *event)
static void cpu_clock_event_start(struct perf_event *event, int flags)
{
+ event->hw.state = 0;
local64_set(&event->hw.prev_count, local_clock());
perf_swevent_start_hrtimer(event);
}
static void cpu_clock_event_stop(struct perf_event *event, int flags)
{
+ event->hw.state = PERF_HES_STOPPED;
perf_swevent_cancel_hrtimer(event);
if (flags & PERF_EF_UPDATE)
cpu_clock_event_update(event);
@@ -11950,12 +11958,14 @@ static void task_clock_event_update(struct perf_event *event, u64 now)
static void task_clock_event_start(struct perf_event *event, int flags)
{
+ event->hw.state = 0;
local64_set(&event->hw.prev_count, event->ctx->time);
perf_swevent_start_hrtimer(event);
}
static void task_clock_event_stop(struct perf_event *event, int flags)
{
+ event->hw.state = PERF_HES_STOPPED;
perf_swevent_cancel_hrtimer(event);
if (flags & PERF_EF_UPDATE)
task_clock_event_update(event, event->ctx->time);
diff --git a/kernel/futex/core.c b/kernel/futex/core.c
index 125804fbb5cb..2e77a6e5c865 100644
--- a/kernel/futex/core.c
+++ b/kernel/futex/core.c
@@ -1680,10 +1680,10 @@ static bool futex_ref_get(struct futex_private_hash *fph)
{
struct mm_struct *mm = fph->mm;
- guard(rcu)();
+ guard(preempt)();
- if (smp_load_acquire(&fph->state) == FR_PERCPU) {
- this_cpu_inc(*mm->futex_ref);
+ if (READ_ONCE(fph->state) == FR_PERCPU) {
+ __this_cpu_inc(*mm->futex_ref);
return true;
}
@@ -1694,10 +1694,10 @@ static bool futex_ref_put(struct futex_private_hash *fph)
{
struct mm_struct *mm = fph->mm;
- guard(rcu)();
+ guard(preempt)();
- if (smp_load_acquire(&fph->state) == FR_PERCPU) {
- this_cpu_dec(*mm->futex_ref);
+ if (READ_ONCE(fph->state) == FR_PERCPU) {
+ __this_cpu_dec(*mm->futex_ref);
return false;
}
diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index f1ebf67b48e2..f754a60de848 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -9606,7 +9606,7 @@ static int tg_set_cfs_bandwidth(struct task_group *tg,
guard(rq_lock_irq)(rq);
cfs_rq->runtime_enabled = runtime_enabled;
- cfs_rq->runtime_remaining = 0;
+ cfs_rq->runtime_remaining = 1;
if (cfs_rq->throttled)
unthrottle_cfs_rq(cfs_rq);
diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
index 25970dbbb279..5b752324270b 100644
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -6024,20 +6024,17 @@ void unthrottle_cfs_rq(struct cfs_rq *cfs_rq)
struct sched_entity *se = cfs_rq->tg->se[cpu_of(rq)];
/*
- * It's possible we are called with !runtime_remaining due to things
- * like user changed quota setting(see tg_set_cfs_bandwidth()) or async
- * unthrottled us with a positive runtime_remaining but other still
- * running entities consumed those runtime before we reached here.
+ * It's possible we are called with runtime_remaining < 0 due to things
+ * like async unthrottled us with a positive runtime_remaining but other
+ * still running entities consumed those runtime before we reached here.
*
- * Anyway, we can't unthrottle this cfs_rq without any runtime remaining
- * because any enqueue in tg_unthrottle_up() will immediately trigger a
- * throttle, which is not supposed to happen on unthrottle path.
+ * We can't unthrottle this cfs_rq without any runtime remaining because
+ * any enqueue in tg_unthrottle_up() will immediately trigger a throttle,
+ * which is not supposed to happen on unthrottle path.
*/
if (cfs_rq->runtime_enabled && cfs_rq->runtime_remaining <= 0)
return;
- se = cfs_rq->tg->se[cpu_of(rq)];
-
cfs_rq->throttled = 0;
update_rq_clock(rq);
diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c
index 1244d2c5c384..afcd3747264d 100644
--- a/kernel/trace/ring_buffer.c
+++ b/kernel/trace/ring_buffer.c
@@ -7344,6 +7344,10 @@ consume:
goto out;
}
+ /* Did the reader catch up with the writer? */
+ if (cpu_buffer->reader_page == cpu_buffer->commit_page)
+ goto out;
+
reader = rb_get_reader_page(cpu_buffer);
if (WARN_ON(!reader))
goto out;
diff --git a/kernel/trace/trace_events_hist.c b/kernel/trace/trace_events_hist.c
index 1d536219b624..6bfaf1210dd2 100644
--- a/kernel/trace/trace_events_hist.c
+++ b/kernel/trace/trace_events_hist.c
@@ -3272,14 +3272,16 @@ static struct field_var *create_field_var(struct hist_trigger_data *hist_data,
var = create_var(hist_data, file, field_name, val->size, val->type);
if (IS_ERR(var)) {
hist_err(tr, HIST_ERR_VAR_CREATE_FIND_FAIL, errpos(field_name));
- kfree(val);
+ destroy_hist_field(val, 0);
ret = PTR_ERR(var);
goto err;
}
field_var = kzalloc(sizeof(struct field_var), GFP_KERNEL);
if (!field_var) {
- kfree(val);
+ destroy_hist_field(val, 0);
+ kfree_const(var->type);
+ kfree(var->var.name);
kfree(var);
ret = -ENOMEM;
goto err;
diff --git a/kernel/trace/trace_fprobe.c b/kernel/trace/trace_fprobe.c
index ad9d6347b5fa..8001dbf16891 100644
--- a/kernel/trace/trace_fprobe.c
+++ b/kernel/trace/trace_fprobe.c
@@ -106,13 +106,14 @@ static struct tracepoint_user *__tracepoint_user_init(const char *name, struct t
if (!tuser->name)
return NULL;
+ /* Register tracepoint if it is loaded. */
if (tpoint) {
+ tuser->tpoint = tpoint;
ret = tracepoint_user_register(tuser);
if (ret)
return ERR_PTR(ret);
}
- tuser->tpoint = tpoint;
tuser->refcount = 1;
INIT_LIST_HEAD(&tuser->list);
list_add(&tuser->list, &tracepoint_user_list);
@@ -1513,6 +1514,10 @@ static int disable_trace_fprobe(struct trace_event_call *call,
if (!trace_probe_is_enabled(tp)) {
list_for_each_entry(tf, trace_probe_probe_list(tp), tp.list) {
unregister_fprobe(&tf->fp);
+ if (tf->tuser) {
+ tracepoint_user_put(tf->tuser);
+ tf->tuser = NULL;
+ }
}
}