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 07:21:35 -0500 |
| commit | 49ffdc3589d82d410f134c75c739c4fb44c6a233 (patch) | |
| tree | 0282c222880964a5e0133968b762e8c8cd067b87 /include | |
| parent | d4e45ca6db6786f40a72daf7a44bf54dcc237f31 (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 04307a19cde3..64ada9cc3886 100644 --- a/include/linux/trace_events.h +++ b/include/linux/trace_events.h @@ -682,6 +682,11 @@ 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) \ |