diff options
Diffstat (limited to 'include/linux/sbitmap.h')
| -rw-r--r-- | include/linux/sbitmap.h | 38 |
1 files changed, 38 insertions, 0 deletions
diff --git a/include/linux/sbitmap.h b/include/linux/sbitmap.h index 841585f6e5f2..804a50983ec5 100644 --- a/include/linux/sbitmap.h +++ b/include/linux/sbitmap.h @@ -23,6 +23,8 @@ #include <linux/kernel.h> #include <linux/slab.h> +struct seq_file; + /** * struct sbitmap_word - Word in a &struct sbitmap. */ @@ -127,6 +129,12 @@ struct sbitmap_queue { * @round_robin: Allocate bits in strict round-robin order. */ bool round_robin; + + /** + * @min_shallow_depth: The minimum shallow depth which may be passed to + * sbitmap_queue_get_shallow() or __sbitmap_queue_get_shallow(). + */ + unsigned int min_shallow_depth; }; /** @@ -390,6 +398,9 @@ int __sbitmap_queue_get(struct sbitmap_queue *sbq); * @shallow_depth: The maximum number of bits to allocate from a single word. * See sbitmap_get_shallow(). * + * If you call this, make sure to call sbitmap_queue_min_shallow_depth() after + * initializing @sbq. + * * Return: Non-negative allocated bit number if successful, -1 otherwise. */ int __sbitmap_queue_get_shallow(struct sbitmap_queue *sbq, @@ -424,6 +435,9 @@ static inline int sbitmap_queue_get(struct sbitmap_queue *sbq, * @shallow_depth: The maximum number of bits to allocate from a single word. * See sbitmap_get_shallow(). * + * If you call this, make sure to call sbitmap_queue_min_shallow_depth() after + * initializing @sbq. + * * Return: Non-negative allocated bit number if successful, -1 otherwise. */ static inline int sbitmap_queue_get_shallow(struct sbitmap_queue *sbq, @@ -439,6 +453,23 @@ static inline int sbitmap_queue_get_shallow(struct sbitmap_queue *sbq, } /** + * sbitmap_queue_min_shallow_depth() - Inform a &struct sbitmap_queue of the + * minimum shallow depth that will be used. + * @sbq: Bitmap queue in question. + * @min_shallow_depth: The minimum shallow depth that will be passed to + * sbitmap_queue_get_shallow() or __sbitmap_queue_get_shallow(). + * + * sbitmap_queue_clear() batches wakeups as an optimization. The batch size + * depends on the depth of the bitmap. Since the shallow allocation functions + * effectively operate with a different depth, the shallow depth must be taken + * into account when calculating the batch size. This function must be called + * with the minimum shallow depth that will be used. Failure to do so can result + * in missed wakeups. + */ +void sbitmap_queue_min_shallow_depth(struct sbitmap_queue *sbq, + unsigned int min_shallow_depth); + +/** * sbitmap_queue_clear() - Free an allocated bit and wake up waiters on a * &struct sbitmap_queue. * @sbq: Bitmap to free from. @@ -484,6 +515,13 @@ static inline struct sbq_wait_state *sbq_wait_ptr(struct sbitmap_queue *sbq, void sbitmap_queue_wake_all(struct sbitmap_queue *sbq); /** + * sbitmap_queue_wake_up() - Wake up some of waiters in one waitqueue + * on a &struct sbitmap_queue. + * @sbq: Bitmap queue to wake up. + */ +void sbitmap_queue_wake_up(struct sbitmap_queue *sbq); + +/** * sbitmap_queue_show() - Dump &struct sbitmap_queue information to a &struct * seq_file. * @sbq: Bitmap queue to show. |