locking, rwsem: Annotate inner lock as raw

There is no reason to allow the lock protecting rwsems (the
ownerless variant) to be preemptible on -rt. Convert it to raw.

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>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

2 files changed, 7 insertions, 5 deletions

diff --git a/include/linux/rwsem-spinlock.h b/include/linux/rwsem-spinlock.h
index 34701241b673..d5b13bc07a0b 100644
--- a/include/linux/rwsem-spinlock.h
+++ b/include/linux/rwsem-spinlock.h
@@ -22,7 +22,7 @@
  */
 struct rw_semaphore {
         __s32                   activity;
-        spinlock_t              wait_lock;
+        raw_spinlock_t          wait_lock;
         struct list_head        wait_list;
 #ifdef CONFIG_DEBUG_LOCK_ALLOC
         struct lockdep_map dep_map;
diff --git a/include/linux/rwsem.h b/include/linux/rwsem.h
index 6a6741440cb7..63d406554391 100644
--- a/include/linux/rwsem.h
+++ b/include/linux/rwsem.h
@@ -25,7 +25,7 @@ struct rw_semaphore;
 /* All arch specific implementations share the same struct */
 struct rw_semaphore {
         long                    count;
-        spinlock_t              wait_lock;
+        raw_spinlock_t          wait_lock;
         struct list_head        wait_list;
 #ifdef CONFIG_DEBUG_LOCK_ALLOC
         struct lockdep_map      dep_map;
@@ -56,9 +56,11 @@ static inline int rwsem_is_locked(struct rw_semaphore *sem)
 # define __RWSEM_DEP_MAP_INIT(lockname)
 #endif
 
-#define __RWSEM_INITIALIZER(name) \
-        { RWSEM_UNLOCKED_VALUE, __SPIN_LOCK_UNLOCKED(name.wait_lock),   \
-          LIST_HEAD_INIT((name).wait_list) __RWSEM_DEP_MAP_INIT(name) }
+#define __RWSEM_INITIALIZER(name)                       \
+        { RWSEM_UNLOCKED_VALUE,                         \
+          __RAW_SPIN_LOCK_UNLOCKED(name.wait_lock),     \
+          LIST_HEAD_INIT((name).wait_list)              \
+          __RWSEM_DEP_MAP_INIT(name) }
 
 #define DECLARE_RWSEM(name) \
         struct rw_semaphore name = __RWSEM_INITIALIZER(name)