sched, wait: Use wrapper functions

epoll should not touch flags in wait_queue_t. This patch introduces a new
function __add_wait_queue_exclusive(), for the users, who use wait queue as a
LIFO queue.

__add_wait_queue_tail_exclusive() is introduced too instead of
add_wait_queue_exclusive_locked(). remove_wait_queue_locked() is removed, as
it is a duplicate of __remove_wait_queue(), disliked by users, and with less
users.

Signed-off-by: Changli Gao <xiaosuo@gmail.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Paul Menage <menage@google.com>
Cc: Li Zefan <lizf@cn.fujitsu.com>
Cc: Davide Libenzi <davidel@xmailserver.org>
Cc: <containers@lists.linux-foundation.org>
LKML-Reference: <1273214006-2979-1-git-send-email-xiaosuo@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 1 insertions, 2 deletions

diff --git a/kernel/sched.c b/kernel/sched.c
index 39aa9c7e22c0..b531d7934083 100644
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -3983,8 +3983,7 @@ do_wait_for_common(struct completion *x, long timeout, int state)
         if (!x->done) {
                 DECLARE_WAITQUEUE(wait, current);
 
-                wait.flags |= WQ_FLAG_EXCLUSIVE;
-                __add_wait_queue_tail(&x->wait, &wait);
+                __add_wait_queue_tail_exclusive(&x->wait, &wait);
                 do {
                         if (signal_pending_state(state, current)) {
                                 timeout = -ERESTARTSYS;