Commit 0db61388 authored by Namhyung Kim's avatar Namhyung Kim Committed by Ingo Molnar
Browse files

perf/core: Change to POLLERR for pinned events with error 



Commit:

  f4b07fd6 ("perf/core: Use POLLHUP for pinned events in error")

started to emit POLLHUP for pinned events in an error state.

But the POLLHUP is also used to signal events that the attached task is
terminated.  To distinguish pinned per-task events in the error state
it would need to check if the task is live.

Change it to POLLERR to make it clear.

Suggested-by: default avatarGabriel Marin <gmx@google.com>
Signed-off-by: default avatarNamhyung Kim <namhyung@kernel.org>
Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20250422223318.180343-1-namhyung@kernel.org
parent bc337235

kernel/events/core.c

+2 −2
Original line number Diff line number Diff line
@@ -3943,7 +3943,7 @@ static int merge_sched_in(struct perf_event *event, void *data) 
			perf_event_set_state(event, PERF_EVENT_STATE_ERROR);



			if (*perf_event_fasync(event))

				event->pending_kill = POLL_HUP;

				event->pending_kill = POLL_ERR;



			perf_event_wakeup(event);

		} else {
@@ -6075,7 +6075,7 @@ static __poll_t perf_poll(struct file *file, poll_table *wait) 


	if (unlikely(READ_ONCE(event->state) == PERF_EVENT_STATE_ERROR &&

		     event->attr.pinned))

		return events;

		return EPOLLERR;



	/*

	 * Pin the event->rb by taking event->mmap_mutex; otherwise