posix-timers: Zero settings value in common code

Zero out the settings struct in the common code so the callbacks do not
have to do it themself.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: John Stultz <john.stultz@linaro.org>
Link: http://lkml.kernel.org/r/20170530211657.200870713@linutronix.de

kernel/time/posix-cpu-timers.c

@@ -719,10 +719,8 @@ static void posix_cpu_timer_get(struct k_itimer *timer, struct itimerspec64 *itp
 	 */
 	itp->it_interval = ns_to_timespec64(timer->it.cpu.incr);
 
-	if (timer->it.cpu.expires == 0) {	/* Timer not armed at all.  */
-		itp->it_value.tv_sec = itp->it_value.tv_nsec = 0;
+	if (!timer->it.cpu.expires)
 		return;
-	}
 
 	/*
 	 * Sample the clock to take the difference with the expiry time.
@@ -746,7 +744,6 @@ static void posix_cpu_timer_get(struct k_itimer *timer, struct itimerspec64 *itp
 			 * Call the timer disarmed, nothing else to do.
 			 */
 			timer->it.cpu.expires = 0;
-			itp->it_value = ns_to_timespec64(timer->it.cpu.expires);
 			return;
 		} else {
 			cpu_timer_sample_group(timer->it_clock, p, &now);

kernel/time/posix-timers.c

@@ -645,8 +645,6 @@ common_timer_get(struct k_itimer *timr, struct itimerspec64 *cur_setting)
 	struct timespec64 ts64;
 	bool sig_none;
 
-	memset(cur_setting, 0, sizeof(*cur_setting));
-
 	sig_none = (timr->it_sigev_notify & ~SIGEV_THREAD_ID) != SIGEV_NONE;
 	iv = timr->it_interval;
 
@@ -705,6 +703,7 @@ SYSCALL_DEFINE2(timer_gettime, timer_t, timer_id,
 	if (!timr)
 		return -EINVAL;
 
+	memset(&cur_setting64, 0, sizeof(cur_setting64));
 	kc = timr->kclock;
 	if (WARN_ON_ONCE(!kc || !kc->timer_get))
 		ret = -EINVAL;