eventpoll: fix missing wakeup for ovflist in ep_poll_callback
In the event that we add to ovflist, before commit 339ddb53d373
("fs/epoll: remove unnecessary wakeups of nested epoll") we would be
woken up by ep_scan_ready_list, and did no wakeup in ep_poll_callback.
With that wakeup removed, if we add to ovflist here, we may never wake
up. Rather than adding back the ep_scan_ready_list wakeup - which was
resulting in unnecessary wakeups, trigger a wake-up in ep_poll_callback.
We noticed that one of our workloads was missing wakeups starting with
339ddb53d373 and upon manual inspection, this wakeup seemed missing to me.
With this patch added, we no longer see missing wakeups. I haven't yet
tried to make a small reproducer, but the existing kselftests in
filesystem/epoll passed for me with this patch.
[[email protected]: use if/elif instead of goto + cleanup suggested by Roman]
Link: http://lkml.kernel.org/r/[email protected]
Fixes: 339ddb53d373 ("fs/epoll: remove unnecessary wakeups of nested epoll")
Signed-off-by: Khazhismel Kumykov <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Reviewed-by: Roman Penyaev <[email protected]>
Cc: Alexander Viro <[email protected]>
Cc: Roman Penyaev <[email protected]>
Cc: Heiher <[email protected]>
Cc: Jason Baron <[email protected]>
Cc: <[email protected]>
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Linus Torvalds <[email protected]>
1 file changed
