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authorIngo Molnar <mingo@elte.hu>2006-07-03 00:24:53 -0700
committerLinus Torvalds <torvalds@g5.osdl.org>2006-07-03 15:27:04 -0700
commit4ea2176dfa714882e88180b474e4cbcd888b70af (patch)
tree7ff3810f6b8750c226234887bb3063d91e1d71c3 /include/linux
parenta8f24a3978c5f82419e1c90dc90460731204f46f (diff)
[PATCH] lockdep: prove rwsem locking correctness
Use the lock validator framework to prove rwsem locking correctness. 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>
Diffstat (limited to 'include/linux')
-rw-r--r--include/linux/rwsem-spinlock.h23
-rw-r--r--include/linux/rwsem.h59
2 files changed, 46 insertions, 36 deletions
diff --git a/include/linux/rwsem-spinlock.h b/include/linux/rwsem-spinlock.h
index d68afcc36ac9..ae1fcadd598e 100644
--- a/include/linux/rwsem-spinlock.h
+++ b/include/linux/rwsem-spinlock.h
@@ -32,18 +32,37 @@ struct rw_semaphore {
__s32 activity;
spinlock_t wait_lock;
struct list_head wait_list;
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+ struct lockdep_map dep_map;
+#endif
};
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+# define __RWSEM_DEP_MAP_INIT(lockname) , .dep_map = { .name = #lockname }
+#else
+# define __RWSEM_DEP_MAP_INIT(lockname)
+#endif
+
#define __RWSEM_INITIALIZER(name) \
-{ 0, SPIN_LOCK_UNLOCKED, LIST_HEAD_INIT((name).wait_list) }
+{ 0, SPIN_LOCK_UNLOCKED, LIST_HEAD_INIT((name).wait_list) __RWSEM_DEP_MAP_INIT(name) }
#define DECLARE_RWSEM(name) \
struct rw_semaphore name = __RWSEM_INITIALIZER(name)
-extern void FASTCALL(init_rwsem(struct rw_semaphore *sem));
+extern void __init_rwsem(struct rw_semaphore *sem, const char *name,
+ struct lock_class_key *key);
+
+#define init_rwsem(sem) \
+do { \
+ static struct lock_class_key __key; \
+ \
+ __init_rwsem((sem), #sem, &__key); \
+} while (0)
+
extern void FASTCALL(__down_read(struct rw_semaphore *sem));
extern int FASTCALL(__down_read_trylock(struct rw_semaphore *sem));
extern void FASTCALL(__down_write(struct rw_semaphore *sem));
+extern void FASTCALL(__down_write_nested(struct rw_semaphore *sem, int subclass));
extern int FASTCALL(__down_write_trylock(struct rw_semaphore *sem));
extern void FASTCALL(__up_read(struct rw_semaphore *sem));
extern void FASTCALL(__up_write(struct rw_semaphore *sem));
diff --git a/include/linux/rwsem.h b/include/linux/rwsem.h
index 93581534b915..658afb37c3f5 100644
--- a/include/linux/rwsem.h
+++ b/include/linux/rwsem.h
@@ -27,64 +27,55 @@ struct rw_semaphore;
/*
* lock for reading
*/
-static inline void down_read(struct rw_semaphore *sem)
-{
- might_sleep();
- __down_read(sem);
-}
+extern void down_read(struct rw_semaphore *sem);
/*
* trylock for reading -- returns 1 if successful, 0 if contention
*/
-static inline int down_read_trylock(struct rw_semaphore *sem)
-{
- int ret;
- ret = __down_read_trylock(sem);
- return ret;
-}
+extern int down_read_trylock(struct rw_semaphore *sem);
/*
* lock for writing
*/
-static inline void down_write(struct rw_semaphore *sem)
-{
- might_sleep();
- __down_write(sem);
-}
+extern void down_write(struct rw_semaphore *sem);
/*
* trylock for writing -- returns 1 if successful, 0 if contention
*/
-static inline int down_write_trylock(struct rw_semaphore *sem)
-{
- int ret;
- ret = __down_write_trylock(sem);
- return ret;
-}
+extern int down_write_trylock(struct rw_semaphore *sem);
/*
* release a read lock
*/
-static inline void up_read(struct rw_semaphore *sem)
-{
- __up_read(sem);
-}
+extern void up_read(struct rw_semaphore *sem);
/*
* release a write lock
*/
-static inline void up_write(struct rw_semaphore *sem)
-{
- __up_write(sem);
-}
+extern void up_write(struct rw_semaphore *sem);
/*
* downgrade write lock to read lock
*/
-static inline void downgrade_write(struct rw_semaphore *sem)
-{
- __downgrade_write(sem);
-}
+extern void downgrade_write(struct rw_semaphore *sem);
+
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+/*
+ * nested locking:
+ */
+extern void down_read_nested(struct rw_semaphore *sem, int subclass);
+extern void down_write_nested(struct rw_semaphore *sem, int subclass);
+/*
+ * Take/release a lock when not the owner will release it:
+ */
+extern void down_read_non_owner(struct rw_semaphore *sem);
+extern void up_read_non_owner(struct rw_semaphore *sem);
+#else
+# define down_read_nested(sem, subclass) down_read(sem)
+# define down_write_nested(sem, subclass) down_write(sem)
+# define down_read_non_owner(sem) down_read(sem)
+# define up_read_non_owner(sem) up_read(sem)
+#endif
#endif /* __KERNEL__ */
#endif /* _LINUX_RWSEM_H */