diff options
Diffstat (limited to 'kernel/events')
| -rw-r--r-- | kernel/events/core.c | 21 |
1 files changed, 20 insertions, 1 deletions
diff --git a/kernel/events/core.c b/kernel/events/core.c index 733c61636f0d..15e58d4ea035 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -3587,6 +3587,19 @@ static int perf_event_read_one(struct perf_event *event, return n * sizeof(u64); } +static bool is_event_hup(struct perf_event *event) +{ + bool no_children; + + if (event->state != PERF_EVENT_STATE_EXIT) + return false; + + mutex_lock(&event->child_mutex); + no_children = list_empty(&event->child_list); + mutex_unlock(&event->child_mutex); + return no_children; +} + /* * Read the performance event - simple non blocking version for now */ @@ -3632,7 +3645,7 @@ static unsigned int perf_poll(struct file *file, poll_table *wait) poll_wait(file, &event->waitq, wait); - if (event->state == PERF_EVENT_STATE_EXIT) + if (is_event_hup(event)) return events; /* @@ -7580,6 +7593,12 @@ static void sync_child_event(struct perf_event *child_event, mutex_unlock(&parent_event->child_mutex); /* + * Make sure user/parent get notified, that we just + * lost one event. + */ + perf_event_wakeup(parent_event); + + /* * Release the parent event, if this was the last * reference to it. */ |