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perf: Fix cgroup state vs ERROR

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[ Upstream commit 61988e36dc5457cdff7ae7927e8d9ad1419ee998 ]

While chasing down a missing perf_cgroup_event_disable() elsewhere,
Leo Yan found that both perf_put_aux_event() and
perf_remove_sibling_event() were also missing one.

Specifically, the rule is that events that switch to OFF,ERROR need to
call perf_cgroup_event_disable().

Unify the disable paths to ensure this.

Fixes: ab43762ef0 ("perf: Allow normal events to output AUX data")
Fixes: 9f0c4fa111 ("perf/core: Add a new PERF_EV_CAP_SIBLING event capability")
Reported-by: Leo Yan <leo.yan@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20250605123343.GD35970@noisy.programming.kicks-ass.net
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
Peter Zijlstra
2025-06-05 12:37:11 +02:00
committed by Greg Kroah-Hartman
parent 2ee6044a69
commit bddec73050
1 changed files with 30 additions and 21 deletions
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51
kernel/events/core.c
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@@ -2067,8 +2067,9 @@ perf_aux_output_match(struct perf_event *event, struct perf_event *aux_event)
} }
static void put_event(struct perf_event *event); static void put_event(struct perf_event *event);
static void event_sched_out(struct perf_event *event, static void __event_disable(struct perf_event *event,
struct perf_event_context *ctx); struct perf_event_context *ctx,
enum perf_event_state state);
static void perf_put_aux_event(struct perf_event *event) static void perf_put_aux_event(struct perf_event *event)
{ {
@@ -2101,8 +2102,7 @@ static void perf_put_aux_event(struct perf_event *event)
* state so that we don't try to schedule it again. Note * state so that we don't try to schedule it again. Note
* that perf_event_enable() will clear the ERROR status. * that perf_event_enable() will clear the ERROR status.
*/ */
event_sched_out(iter, ctx); __event_disable(iter, ctx, PERF_EVENT_STATE_ERROR);
perf_event_set_state(event, PERF_EVENT_STATE_ERROR);
} }
} }
@@ -2156,18 +2156,6 @@ static inline struct list_head *get_event_list(struct perf_event *event)
&event->pmu_ctx->flexible_active; &event->pmu_ctx->flexible_active;
} }
/*
* Events that have PERF_EV_CAP_SIBLING require being part of a group and
* cannot exist on their own, schedule them out and move them into the ERROR
* state. Also see _perf_event_enable(), it will not be able to recover
* this ERROR state.
*/
static inline void perf_remove_sibling_event(struct perf_event *event)
{
event_sched_out(event, event->ctx);
perf_event_set_state(event, PERF_EVENT_STATE_ERROR);
}
static void perf_group_detach(struct perf_event *event) static void perf_group_detach(struct perf_event *event)
{ {
struct perf_event *leader = event->group_leader; struct perf_event *leader = event->group_leader;
@@ -2203,8 +2191,15 @@ static void perf_group_detach(struct perf_event *event)
*/ */
list_for_each_entry_safe(sibling, tmp, &event->sibling_list, sibling_list) { list_for_each_entry_safe(sibling, tmp, &event->sibling_list, sibling_list) {
/*
* Events that have PERF_EV_CAP_SIBLING require being part of
* a group and cannot exist on their own, schedule them out
* and move them into the ERROR state. Also see
* _perf_event_enable(), it will not be able to recover this
* ERROR state.
*/
if (sibling->event_caps & PERF_EV_CAP_SIBLING) if (sibling->event_caps & PERF_EV_CAP_SIBLING)
perf_remove_sibling_event(sibling); __event_disable(sibling, ctx, PERF_EVENT_STATE_ERROR);
sibling->group_leader = sibling; sibling->group_leader = sibling;
list_del_init(&sibling->sibling_list); list_del_init(&sibling->sibling_list);
@@ -2437,6 +2432,15 @@ static void perf_remove_from_context(struct perf_event *event, unsigned long fla
event_function_call(event, __perf_remove_from_context, (void *)flags); event_function_call(event, __perf_remove_from_context, (void *)flags);
} }
static void __event_disable(struct perf_event *event,
struct perf_event_context *ctx,
enum perf_event_state state)
{
event_sched_out(event, ctx);
perf_cgroup_event_disable(event, ctx);
perf_event_set_state(event, state);
}
/* /*
* Cross CPU call to disable a performance event * Cross CPU call to disable a performance event
*/ */
@@ -2455,13 +2459,18 @@ static void __perf_event_disable(struct perf_event *event,
perf_pmu_disable(event->pmu_ctx->pmu); perf_pmu_disable(event->pmu_ctx->pmu);
/*
* When disabling a group leader, the whole group becomes ineligible
* to run, so schedule out the full group.
*/
if (event == event->group_leader) if (event == event->group_leader)
group_sched_out(event, ctx); group_sched_out(event, ctx);
else
event_sched_out(event, ctx);
perf_event_set_state(event, PERF_EVENT_STATE_OFF); /*
perf_cgroup_event_disable(event, ctx); * But only mark the leader OFF; the siblings will remain
* INACTIVE.
*/
__event_disable(event, ctx, PERF_EVENT_STATE_OFF);
perf_pmu_enable(event->pmu_ctx->pmu); perf_pmu_enable(event->pmu_ctx->pmu);
} }