From 7b4c5a37544ba22c6ebe72c0d4ea56c953459fa5 Mon Sep 17 00:00:00 2001 From: Luo Gengkun Date: Thu, 26 Jun 2025 13:54:03 +0000 Subject: [PATCH] perf/core: Fix the WARN_ON_ONCE is out of lock protected region commit 3172fb986666 ("perf/core: Fix WARN in perf_cgroup_switch()") try to fix a concurrency problem between perf_cgroup_switch and perf_cgroup_event_disable. But it does not to move the WARN_ON_ONCE into lock-protected region, so the warning is still be triggered. Fixes: 3172fb986666 ("perf/core: Fix WARN in perf_cgroup_switch()") Signed-off-by: Luo Gengkun Signed-off-by: Peter Zijlstra (Intel) Link: https://lkml.kernel.org/r/20250626135403.2454105-1-luogengkun@huaweicloud.com --- kernel/events/core.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/kernel/events/core.c b/kernel/events/core.c index 7281230044d0..bf2118c22126 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -951,8 +951,6 @@ static void perf_cgroup_switch(struct task_struct *task) if (READ_ONCE(cpuctx->cgrp) == NULL) return; - WARN_ON_ONCE(cpuctx->ctx.nr_cgroups == 0); - cgrp = perf_cgroup_from_task(task, NULL); if (READ_ONCE(cpuctx->cgrp) == cgrp) return; @@ -964,6 +962,8 @@ static void perf_cgroup_switch(struct task_struct *task) if (READ_ONCE(cpuctx->cgrp) == NULL) return; + WARN_ON_ONCE(cpuctx->ctx.nr_cgroups == 0); + perf_ctx_disable(&cpuctx->ctx, true); ctx_sched_out(&cpuctx->ctx, NULL, EVENT_ALL|EVENT_CGROUP); -- 2.50.1