diff options
| author | Petr Pavlu <petr.pavlu@suse.com> | 2026-02-19 17:27:02 +0100 |
|---|---|---|
| committer | Sasha Levin <sashal@kernel.org> | 2026-03-04 07:21:46 -0500 |
| commit | f0b54db56eaeef4b6a82acf4cf5e465f4221f8fe (patch) | |
| tree | a03ec2b2148b4bb5346cfd062acf0469e662ac21 /include | |
| parent | d43e587644531bd387fb8a99e07e83c13dc9832e (diff) | |
tracing: Wake up poll waiters for hist files when removing an event
[ Upstream commit 9678e53179aa7e907360f5b5b275769008a69b80 ]
The event_hist_poll() function attempts to verify whether an event file is
being removed, but this check may not occur or could be unnecessarily
delayed. This happens because hist_poll_wakeup() is currently invoked only
from event_hist_trigger() when a hist command is triggered. If the event
file is being removed, no associated hist command will be triggered and a
waiter will be woken up only after an unrelated hist command is triggered.
Fix the issue by adding a call to hist_poll_wakeup() in
remove_event_file_dir() after setting the EVENT_FILE_FL_FREED flag. This
ensures that a task polling on a hist file is woken up and receives
EPOLLERR.
Cc: stable@vger.kernel.org
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Tom Zanussi <zanussi@kernel.org>
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Link: https://patch.msgid.link/20260219162737.314231-3-petr.pavlu@suse.com
Fixes: 1bd13edbbed6 ("tracing/hist: Add poll(POLLIN) support on hist file")
Signed-off-by: Petr Pavlu <petr.pavlu@suse.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'include')
| -rw-r--r-- | include/linux/trace_events.h | 5 |
1 files changed, 5 insertions, 0 deletions
diff --git a/include/linux/trace_events.h b/include/linux/trace_events.h index 3690221ba3d8..f925034e402d 100644 --- a/include/linux/trace_events.h +++ b/include/linux/trace_events.h @@ -683,6 +683,11 @@ static inline void hist_poll_wakeup(void) #define hist_poll_wait(file, wait) \ poll_wait(file, &hist_poll_wq, wait) + +#else +static inline void hist_poll_wakeup(void) +{ +} #endif #define __TRACE_EVENT_FLAGS(name, value) \ |