From 4d5755b147665912c938504033d958f1115b68ff Mon Sep 17 00:00:00 2001 From: Davidlohr Bueso Date: Fri, 13 Feb 2015 14:39:08 -0800 Subject: [PATCH] epoll: optimize setting task running after blocking After waking up a task waiting for an event, we explicitly mark it as TASK_RUNNING (which is necessary as we do the checks for wakeups as TASK_INTERRUPTIBLE). Once running and dealing with actually delivering the events, we're obviously not planning on calling schedule, thus we can relax the implied barrier and simply update the state with __set_current_state(). Signed-off-by: Davidlohr Bueso Cc: Alexander Viro Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- fs/eventpoll.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/fs/eventpoll.c b/fs/eventpoll.c index d77f94491352..1e009cad8d5c 100644 --- a/fs/eventpoll.c +++ b/fs/eventpoll.c @@ -1639,9 +1639,9 @@ fetch_events: spin_lock_irqsave(&ep->lock, flags); } - __remove_wait_queue(&ep->wq, &wait); - set_current_state(TASK_RUNNING); + __remove_wait_queue(&ep->wq, &wait); + __set_current_state(TASK_RUNNING); } check_events: /* Is it worth to try to dig for events ? */ -- 2.20.1