[PATCH 5/5] pipe: Do not use sync wakeups

[Namhyung Kim <namhyung@kernel.org>]

Sync wakeup is a hint to the scheduler that means a waker would go to
sleep right soon.  So don't use the sync wakeup unless it guarantees
to sleep.

Cc: Ingo Molnar <mingo@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
---
 fs/pipe.c |    6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/fs/pipe.c b/fs/pipe.c
index d2c45e14e6d8..58f4b9b009da 100644
--- a/fs/pipe.c
+++ b/fs/pipe.c
@@ -479,7 +479,7 @@ redo:
 
 	/* Signal writers asynchronously that there is more room. */
 	if (do_wakeup) {
-		wake_up_interruptible_sync_poll(&pipe->wait, POLLOUT | POLLWRNORM);
+		wake_up_interruptible_poll(&pipe->wait, POLLOUT | POLLWRNORM);
 		kill_fasync(&pipe->fasync_writers, SIGIO, POLL_OUT);
 	}
 	if (ret > 0)
@@ -660,7 +660,7 @@ redo2:
 out:
 	__pipe_unlock(pipe);
 	if (do_wakeup) {
-		wake_up_interruptible_sync_poll(&pipe->wait, POLLIN | POLLRDNORM);
+		wake_up_interruptible_poll(&pipe->wait, POLLIN | POLLRDNORM);
 		kill_fasync(&pipe->fasync_readers, SIGIO, POLL_IN);
 	}
 	if (ret > 0) {
@@ -739,7 +739,7 @@ pipe_release(struct inode *inode, struct file *file)
 		pipe->writers--;
 
 	if (pipe->readers || pipe->writers) {
-		wake_up_interruptible_sync_poll(&pipe->wait, POLLIN | POLLOUT | POLLRDNORM | POLLWRNORM | POLLERR | POLLHUP);
+		wake_up_interruptible_poll(&pipe->wait, POLLIN | POLLOUT | POLLRDNORM | POLLWRNORM | POLLERR | POLLHUP);
 		kill_fasync(&pipe->fasync_readers, SIGIO, POLL_IN);
 		kill_fasync(&pipe->fasync_writers, SIGIO, POLL_OUT);
 	}
-- 
1.7.9.2