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-rw-r--r--include/linux/mutex.h24
-rw-r--r--kernel/mutex.c25
2 files changed, 25 insertions, 24 deletions
diff --git a/include/linux/mutex.h b/include/linux/mutex.h
index 93054fc3635c..878cab4f5fcc 100644
--- a/include/linux/mutex.h
+++ b/include/linux/mutex.h
@@ -150,28 +150,6 @@ extern int __must_check mutex_lock_killable(struct mutex *lock);
*/
extern int mutex_trylock(struct mutex *lock);
extern void mutex_unlock(struct mutex *lock);
-
-/**
- * atomic_dec_and_mutex_lock - return holding mutex if we dec to 0
- * @cnt: the atomic which we are to dec
- * @lock: the mutex to return holding if we dec to 0
- *
- * return true and hold lock if we dec to 0, return false otherwise
- */
-static inline int atomic_dec_and_mutex_lock(atomic_t *cnt, struct mutex *lock)
-{
- /* dec if we can't possibly hit 0 */
- if (atomic_add_unless(cnt, -1, 1))
- return 0;
- /* we might hit 0, so take the lock */
- mutex_lock(lock);
- if (!atomic_dec_and_test(cnt)) {
- /* when we actually did the dec, we didn't hit 0 */
- mutex_unlock(lock);
- return 0;
- }
- /* we hit 0, and we hold the lock */
- return 1;
-}
+extern int atomic_dec_and_mutex_lock(atomic_t *cnt, struct mutex *lock);
#endif
diff --git a/kernel/mutex.c b/kernel/mutex.c
index 507cf2b5e9f1..e2d25e9e62ae 100644
--- a/kernel/mutex.c
+++ b/kernel/mutex.c
@@ -471,5 +471,28 @@ int __sched mutex_trylock(struct mutex *lock)
return ret;
}
-
EXPORT_SYMBOL(mutex_trylock);
+
+/**
+ * atomic_dec_and_mutex_lock - return holding mutex if we dec to 0
+ * @cnt: the atomic which we are to dec
+ * @lock: the mutex to return holding if we dec to 0
+ *
+ * return true and hold lock if we dec to 0, return false otherwise
+ */
+int atomic_dec_and_mutex_lock(atomic_t *cnt, struct mutex *lock)
+{
+ /* dec if we can't possibly hit 0 */
+ if (atomic_add_unless(cnt, -1, 1))
+ return 0;
+ /* we might hit 0, so take the lock */
+ mutex_lock(lock);
+ if (!atomic_dec_and_test(cnt)) {
+ /* when we actually did the dec, we didn't hit 0 */
+ mutex_unlock(lock);
+ return 0;
+ }
+ /* we hit 0, and we hold the lock */
+ return 1;
+}
+EXPORT_SYMBOL(atomic_dec_and_mutex_lock);