From: Soheil Hassas Yeganeh <soheil@xxxxxxxxxx> Subject: epoll: pull fatal signal checks into ep_send_events() To simplify the code, pull in checking the fatal signals into ep_send_events(). ep_send_events() is called only from ep_poll(). Note that, previously, we were always checking fatal events, but it is checked only if eavail is true. This should be fine because the goal of that check is to quickly return from epoll_wait() when there is a pending fatal signal. Link: https://lkml.kernel.org/r/20201106231635.3528496-4-soheil.kdev@xxxxxxxxx Signed-off-by: Soheil Hassas Yeganeh <soheil@xxxxxxxxxx> Suggested-by: Willem de Bruijn <willemb@xxxxxxxxxx> Reviewed-by: Eric Dumazet <edumazet@xxxxxxxxxx> Reviewed-by: Willem de Bruijn <willemb@xxxxxxxxxx> Reviewed-by: Khazhismel Kumykov <khazhy@xxxxxxxxxx> Cc: Guantao Liu <guantaol@xxxxxxxxxx> Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- fs/eventpoll.c | 17 ++++++++--------- 1 file changed, 8 insertions(+), 9 deletions(-) --- a/fs/eventpoll.c~epoll-pull-fatal-signal-checks-into-ep_send_events +++ a/fs/eventpoll.c @@ -1625,6 +1625,14 @@ static int ep_send_events(struct eventpo poll_table pt; int res = 0; + /* + * Always short-circuit for fatal signals to allow threads to make a + * timely exit without the chance of finding more events available and + * fetching repeatedly. + */ + if (fatal_signal_pending(current)) + return -EINTR; + init_poll_funcptr(&pt, NULL); mutex_lock(&ep->mtx); @@ -1846,15 +1854,6 @@ fetch_events: } send_events: - if (fatal_signal_pending(current)) { - /* - * Always short-circuit for fatal signals to allow - * threads to make a timely exit without the chance of - * finding more events available and fetching - * repeatedly. - */ - return -EINTR; - } /* * Try to transfer events to user space. In case we get 0 events and * there's still timeout left over, we go trying again in search of _