epoll: move ready event check into proper inline

Move the event readiness check into a proper inline, and use it uniformly
inside ep_poll() code.  Events in the ->ovflist are no less ready than the
ones in ->rdllist.
Signed-off-by: NDavide Libenzi <davidel@xmailserver.org>
Cc: Shawn Bohrer <shawn.bohrer@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

fs/eventpoll.c

@@ -315,6 +315,19 @@ static void ep_nested_calls_init(struct nested_calls *ncalls)
 	spin_lock_init(&ncalls->lock);
 }
 
+/**
+ * ep_events_available - Checks if ready events might be available.
+ *
+ * @ep: Pointer to the eventpoll context.
+ *
+ * Returns: Returns a value different than zero if ready events are available,
+ *          or zero otherwise.
+ */
+static inline int ep_events_available(struct eventpoll *ep)
+{
+	return !list_empty(&ep->rdllist) || ep->ovflist != EP_UNACTIVE_PTR;
+}
+
 /**
  * ep_call_nested - Perform a bound (possibly) nested call, by checking
  *                  that the recursion limit is not exceeded, and that
@@ -1158,7 +1171,7 @@ static int ep_poll(struct eventpoll *ep, struct epoll_event __user *events,
 	spin_lock_irqsave(&ep->lock, flags);
 
 	res = 0;
-	if (list_empty(&ep->rdllist)) {
+	if (!ep_events_available(ep)) {
 		/*
 		 * We don't have any available event to return to the caller.
 		 * We need to sleep here, and we will be wake up by
@@ -1174,7 +1187,7 @@ static int ep_poll(struct eventpoll *ep, struct epoll_event __user *events,
 			 * to TASK_INTERRUPTIBLE before doing the checks.
 			 */
 			set_current_state(TASK_INTERRUPTIBLE);
-			if (!list_empty(&ep->rdllist) || timed_out)
+			if (ep_events_available(ep) || timed_out)
 				break;
 			if (signal_pending(current)) {
 				res = -EINTR;
@@ -1192,7 +1205,7 @@ static int ep_poll(struct eventpoll *ep, struct epoll_event __user *events,
 		set_current_state(TASK_RUNNING);
 	}
 	/* Is it worth to try to dig for events ? */
-	eavail = !list_empty(&ep->rdllist) || ep->ovflist != EP_UNACTIVE_PTR;
+	eavail = ep_events_available(ep);
 
 	spin_unlock_irqrestore(&ep->lock, flags);