perf: Fix the POLL_HUP delivery breakage

The event_limit can be set by the PERF_EVENT_IOC_REFRESH to limit the
number of events. When the event_limit reaches 0, the POLL_HUP signal
should be sent. But it's missed.

The corresponding counter should be stopped when the event_limit reaches
0. It was implemented in the ARCH-specific code. However, since the
commit 9734e25fbf5a ("perf: Fix the throttle logic for a group"), all
the ARCH-specific code has been moved to the generic code. The code to
handle the event_limit was lost.

Add the event->pmu->stop(event, 0); back.

Fixes: 9734e25fbf5a ("perf: Fix the throttle logic for a group")
Closes: https://lore.kernel.org/lkml/aICYAqM5EQUlTqtX@li-2b55cdcc-350b-11b2-a85c-a78bff51fc11.ibm.com/
Reported-by: Sumanth Korikkar <sumanthk@linux.ibm.com>
Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Tested-by: Sumanth Korikkar <sumanthk@linux.ibm.com>
Link: https://lkml.kernel.org/r/20250811182644.1305952-1-kan.liang@linux.intel.com

diff --git a/kernel/events/core.c b/kernel/events/core.c
index 872122e074e5fe4b29e2bfde84f5ffcd384743fc..820127536e62b7e8ed1465cc4cf7a6e075ad52ea 100644 (file)
--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -10330,6 +10330,7 @@ static int __perf_event_overflow(struct perf_event *event,
                ret = 1;
                event->pending_kill = POLL_HUP;
                perf_event_disable_inatomic(event);
+               event->pmu->stop(event, 0);
        }
 
        if (event->attr.sigtrap) {