diff options
| author | Olof Johansson <olof@lixom.net> | 2012-09-11 23:22:25 -0700 |
|---|---|---|
| committer | Olof Johansson <olof@lixom.net> | 2012-09-11 23:22:25 -0700 |
| commit | f46e374c1ea7fafce70a838f09fbd67de3e4d49f (patch) | |
| tree | e191e5316bdb8558bd3e2b0981c715bedd225ca7 /include/linux/kref.h | |
| parent | a4d3621e0d3ecf191961dc9214e4a378a7186780 (diff) | |
| parent | eb8ca943bae2b84c3fc14dfd7a908cb334465fef (diff) | |
Merge branch 'boards' of git://git.kernel.org/pub/scm/linux/kernel/git/horms/renesas into next/boards
* 'boards' of git://git.kernel.org/pub/scm/linux/kernel/git/horms/renesas:
ARM: shmobile: marzen: enable thermal sensor
ARM: shmobile: marzen: fixup regulator id for smsc911x
ARM: shmobile: marzen: add SDHI0 support
+ sync to 3.6-rc4
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 9c07dcebded..65af6887872 100644 --- a/include/linux/kref.h +++ b/include/linux/kref.h @@ -18,6 +18,7 @@ #include <linux/bug.h> #include <linux/atomic.h> #include <linux/kernel.h> +#include <linux/mutex.h> struct kref { atomic_t refcount; @@ -93,4 +94,21 @@ static inline int kref_put(struct kref *kref, void (*release)(struct kref *kref) { return kref_sub(kref, 1, release); } + +static inline int kref_put_mutex(struct kref *kref, + void (*release)(struct kref *kref), + struct mutex *lock) +{ + WARN_ON(release == NULL); + if (unlikely(!atomic_add_unless(&kref->refcount, -1, 1))) { + mutex_lock(lock); + if (unlikely(!atomic_dec_and_test(&kref->refcount))) { + mutex_unlock(lock); + return 0; + } + release(kref); + return 1; + } + return 0; +} #endif /* _KREF_H_ */ |