diff options
Diffstat (limited to 'include/linux/kref.h')
-rw-r--r-- | include/linux/kref.h | 18 |
1 files changed, 18 insertions, 0 deletions
diff --git a/include/linux/kref.h b/include/linux/kref.h index 9c07dcebded7..65af6887872f 100644 --- a/include/linux/kref.h +++ b/include/linux/kref.h | |||
@@ -18,6 +18,7 @@ | |||
18 | #include <linux/bug.h> | 18 | #include <linux/bug.h> |
19 | #include <linux/atomic.h> | 19 | #include <linux/atomic.h> |
20 | #include <linux/kernel.h> | 20 | #include <linux/kernel.h> |
21 | #include <linux/mutex.h> | ||
21 | 22 | ||
22 | struct kref { | 23 | struct kref { |
23 | atomic_t refcount; | 24 | atomic_t refcount; |
@@ -93,4 +94,21 @@ static inline int kref_put(struct kref *kref, void (*release)(struct kref *kref) | |||
93 | { | 94 | { |
94 | return kref_sub(kref, 1, release); | 95 | return kref_sub(kref, 1, release); |
95 | } | 96 | } |
97 | |||
98 | static inline int kref_put_mutex(struct kref *kref, | ||
99 | void (*release)(struct kref *kref), | ||
100 | struct mutex *lock) | ||
101 | { | ||
102 | WARN_ON(release == NULL); | ||
103 | if (unlikely(!atomic_add_unless(&kref->refcount, -1, 1))) { | ||
104 | mutex_lock(lock); | ||
105 | if (unlikely(!atomic_dec_and_test(&kref->refcount))) { | ||
106 | mutex_unlock(lock); | ||
107 | return 0; | ||
108 | } | ||
109 | release(kref); | ||
110 | return 1; | ||
111 | } | ||
112 | return 0; | ||
113 | } | ||
96 | #endif /* _KREF_H_ */ | 114 | #endif /* _KREF_H_ */ |