[PATCH] lockdep: annotate hrtimer base locks

Teach special (recursive) locking code to the lock validator.  Has no effect
on non-lockdep kernels.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

include/linux/hrtimer.h

@@ -91,6 +91,7 @@ struct hrtimer_base {
 	ktime_t			(*get_softirq_time)(void);
 	struct hrtimer		*curr_timer;
 	ktime_t			softirq_time;
+	struct lock_class_key lock_key;
 };
 
 /*

kernel/hrtimer.c

@@ -782,8 +782,10 @@ static void __devinit init_hrtimers_cpu(int cpu)
 	struct hrtimer_base *base = per_cpu(hrtimer_bases, cpu);
 	int i;
 
-	for (i = 0; i < MAX_HRTIMER_BASES; i++, base++)
+	for (i = 0; i < MAX_HRTIMER_BASES; i++, base++) {
 		spin_lock_init(&base->lock);
+		lockdep_set_class(&base->lock, &base->lock_key);
+	}
 }
 
 #ifdef CONFIG_HOTPLUG_CPU