watchdog: Fix sysctl consistency

If it was not possible to enable watchdog for any cpu, switch
watchdog_enabled back to 0, because it's visible via
kernel.watchdog sysctl.
Signed-off-by: Marcin Slusarz <marcin.slusarz@gmail.com>
Signed-off-by: Don Zickus <dzickus@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: <stable@kernel.org>
LKML-Reference: <1296230433-6261-2-git-send-email-dzickus@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

kernel/watchdog.c

@@ -429,9 +429,6 @@ static int watchdog_enable(int cpu)
 		wake_up_process(p);
 	}
 
-	/* if any cpu succeeds, watchdog is considered enabled for the system */
-	watchdog_enabled = 1;
-
 	return 0;
 }
 
@@ -459,12 +456,16 @@ static void watchdog_disable(int cpu)
 static void watchdog_enable_all_cpus(void)
 {
 	int cpu;
-	int result = 0;
+
+	watchdog_enabled = 0;
 
 	for_each_online_cpu(cpu)
-		result += watchdog_enable(cpu);
+		if (!watchdog_enable(cpu))
+			/* if any cpu succeeds, watchdog is considered
+			   enabled for the system */
+			watchdog_enabled = 1;
 
-	if (result)
+	if (!watchdog_enabled)
 		printk(KERN_ERR "watchdog: failed to be enabled on some cpus\n");
 
 }