Re: [PATCH v2] perf/core: restore __perf_remove_from_context when DETACH_EXIT not set
From: David Wang
Date: Tue Jun 03 2025 - 09:04:37 EST
At 2025-06-03 20:54:40, "Peter Zijlstra" <peterz@xxxxxxxxxxxxx> wrote:
>On Tue, Jun 03, 2025 at 02:50:56PM +0200, Peter Zijlstra wrote:
>> On Tue, Jun 03, 2025 at 06:44:58PM +0800, David Wang wrote:
>>
>>
>> > (As yeoreum.yun@xxxxxxx pointed out, the change in perf_remove_from_context() made
>> > perf_event_set_state() happened before list_del_event(), resulting in perf_cgroup_event_disable()
>> > not called.)
>>
>> Aah, d'0h. Let me see what we should do there.
>
>Does this help? This way event_sched_out() will call
>perf_cgroup_event_disable().
>
>
>diff --git a/kernel/events/core.c b/kernel/events/core.c
>index f34c99f8ce8f..adbb0372825f 100644
>--- a/kernel/events/core.c
>+++ b/kernel/events/core.c
>@@ -2494,9 +2494,9 @@ __perf_remove_from_context(struct perf_event *event,
> if (flags & DETACH_REVOKE)
> state = PERF_EVENT_STATE_REVOKED;
> if (flags & DETACH_DEAD) {
>- event->pending_disable = 1;
> state = PERF_EVENT_STATE_DEAD;
> }
>+ event->pending_disable = 1;
> event_sched_out(event, ctx);
> perf_event_set_state(event, min(event->state, state));
>
Ok, I will give it a try and update later.