sched/wait: Add ___wait_cond_timeout() to wait_event*_timeout() too

Commit 4c663cfc ("wait: fix false timeouts when using
wait_event_timeout()") introduced the additional condition checks
after a timeout but only in the "slow" __wait*() paths.

wait_event_timeout(wq, CONDITION, 0) still returns 0 if CONDITION
is already true and we do not call __wait*().

Now that we have ___wait_cond_timeout() we can use it instead to
ensure that __ret will be properly updated.
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20131007183106.GA10973@redhat.comSigned-off-by: Ingo Molnar <mingo@kernel.org>

include/linux/wait.h

@@ -270,7 +270,7 @@ do {									\
 #define wait_event_timeout(wq, condition, timeout)			\
 ({									\
 	long __ret = timeout;						\
-	if (!(condition))						\
+	if (!___wait_cond_timeout(condition))				\
 		__ret = __wait_event_timeout(wq, condition, timeout);	\
 	__ret;								\
 })
@@ -328,7 +328,7 @@ do {									\
 #define wait_event_interruptible_timeout(wq, condition, timeout)	\
 ({									\
 	long __ret = timeout;						\
-	if (!(condition))						\
+	if (!___wait_cond_timeout(condition))				\
 		__ret = __wait_event_interruptible_timeout(wq,		\
 						condition, timeout);	\
 	__ret;								\
@@ -769,7 +769,7 @@ do {									\
 						  timeout)		\
 ({									\
 	long __ret = timeout;						\
-	if (!(condition))						\
+	if (!___wait_cond_timeout(condition))				\
 		__ret = __wait_event_interruptible_lock_irq_timeout(	\
 					wq, condition, lock, timeout);	\
 	__ret;								\