diff options
Diffstat (limited to 'include/linux/lockref.h')
| -rw-r--r-- | include/linux/lockref.h | 16 |
1 files changed, 16 insertions, 0 deletions
diff --git a/include/linux/lockref.h b/include/linux/lockref.h index 01233e01627a..0ea026092d1d 100644 --- a/include/linux/lockref.h +++ b/include/linux/lockref.h @@ -54,6 +54,22 @@ static inline int lockref_get_not_zero(struct lockref *lockref) } /** + * lockref_get_or_lock - Increments count unless the count is 0 + * @lockcnt: pointer to lockref structure + * Return: 1 if count updated successfully or 0 if count was zero + * and we got the lock instead. + */ +static inline int lockref_get_or_lock(struct lockref *lockref) +{ + spin_lock(&lockref->lock); + if (!lockref->count) + return 0; + lockref->count++; + spin_unlock(&lockref->lock); + return 1; +} + +/** * lockref_put_or_lock - decrements count unless count <= 1 before decrement * @lockcnt: pointer to lockref structure * Return: 1 if count updated successfully or 0 if count <= 1 and lock taken |