epoll: drop EPOLLWAKEUP if PM_SLEEP is disabled

Drop EPOLLWAKEUP from epoll events mask if CONFIG_PM_SLEEP is disabled.
Signed-off-by: Amit Pundir <amit.pundir@linaro.org>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

fs/eventpoll.c

@@ -1852,8 +1852,7 @@ SYSCALL_DEFINE4(epoll_ctl, int, epfd, int, op, int, fd,
 		goto error_tgt_fput;
 
 	/* Check if EPOLLWAKEUP is allowed */
-	if ((epds.events & EPOLLWAKEUP) && !capable(CAP_BLOCK_SUSPEND))
-		epds.events &= ~EPOLLWAKEUP;
+	ep_take_care_of_epollwakeup(&epds);
 
 	/*
 	 * We have to check that the file structure underneath the file descriptor

include/uapi/linux/eventpoll.h

@@ -61,5 +61,16 @@ struct epoll_event {
 	__u64 data;
 } EPOLL_PACKED;
 
-
+#ifdef CONFIG_PM_SLEEP
+static inline void ep_take_care_of_epollwakeup(struct epoll_event *epev)
+{
+	if ((epev->events & EPOLLWAKEUP) && !capable(CAP_BLOCK_SUSPEND))
+		epev->events &= ~EPOLLWAKEUP;
+}
+#else
+static inline void ep_take_care_of_epollwakeup(struct epoll_event *epev)
+{
+	epev->events &= ~EPOLLWAKEUP;
+}
+#endif
 #endif /* _UAPI_LINUX_EVENTPOLL_H */