locking, printk: Annotate logbuf_lock as raw

The logbuf_lock lock can be taken in atomic context and therefore
cannot be preempted on -rt - annotate it.

In mainline this change documents the low level nature of
the lock - otherwise there's no functional difference. Lockdep
and Sparse checking will work as usual.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
[ merged and fixed it ]
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/include/linux/ratelimit.h b/include/linux/ratelimit.h
index 2f00715..e11ccb4 100644
--- a/include/linux/ratelimit.h
+++ b/include/linux/ratelimit.h
@@ -8,7 +8,7 @@
 #define DEFAULT_RATELIMIT_BURST		10
 
 struct ratelimit_state {
-	spinlock_t	lock;		/* protect the state */
+	raw_spinlock_t	lock;		/* protect the state */
 
 	int		interval;
 	int		burst;
@@ -20,7 +20,7 @@
 #define DEFINE_RATELIMIT_STATE(name, interval_init, burst_init)		\
 									\
 	struct ratelimit_state name = {					\
-		.lock		= __SPIN_LOCK_UNLOCKED(name.lock),	\
+		.lock		= __RAW_SPIN_LOCK_UNLOCKED(name.lock),	\
 		.interval	= interval_init,			\
 		.burst		= burst_init,				\
 	}
@@ -28,7 +28,7 @@
 static inline void ratelimit_state_init(struct ratelimit_state *rs,
 					int interval, int burst)
 {
-	spin_lock_init(&rs->lock);
+	raw_spin_lock_init(&rs->lock);
 	rs->interval = interval;
 	rs->burst = burst;
 	rs->printed = 0;