diff options
Diffstat (limited to 'include/linux/sbitmap.h')
| -rw-r--r-- | include/linux/sbitmap.h | 102 |
1 files changed, 38 insertions, 64 deletions
diff --git a/include/linux/sbitmap.h b/include/linux/sbitmap.h index 95df357ec009..cc7ad189caa5 100644 --- a/include/linux/sbitmap.h +++ b/include/linux/sbitmap.h @@ -28,19 +28,19 @@ struct seq_file; */ struct sbitmap_word { /** - * @depth: Number of bits being used in @word/@cleared - */ - unsigned long depth; - - /** * @word: word holding free bits */ - unsigned long word ____cacheline_aligned_in_smp; + unsigned long word; /** * @cleared: word holding cleared bits */ unsigned long cleared ____cacheline_aligned_in_smp; + + /** + * @swap_lock: serializes simultaneous updates of ->word and ->cleared + */ + raw_spinlock_t swap_lock; } ____cacheline_aligned_in_smp; /** @@ -75,7 +75,7 @@ struct sbitmap { */ struct sbitmap_word *map; - /* + /** * @alloc_hint: Cache of last successfully allocated or freed bit. * * This is per-cpu, which allows multiple users to stick to different @@ -92,11 +92,6 @@ struct sbitmap { */ struct sbq_wait_state { /** - * @wait_cnt: Number of frees remaining before we wake up. - */ - atomic_t wait_cnt; - - /** * @wait: Wait queue. */ wait_queue_head_t wait; @@ -133,16 +128,27 @@ struct sbitmap_queue { */ struct sbq_wait_state *ws; - /* + /** * @ws_active: count of currently active ws waitqueues */ atomic_t ws_active; /** * @min_shallow_depth: The minimum shallow depth which may be passed to - * sbitmap_queue_get_shallow() or __sbitmap_queue_get_shallow(). + * sbitmap_queue_get_shallow() */ unsigned int min_shallow_depth; + + /** + * @completion_cnt: Number of bits cleared passed to the + * wakeup function. + */ + atomic_t completion_cnt; + + /** + * @wakeup_cnt: Number of thread wake ups issued. + */ + atomic_t wakeup_cnt; }; /** @@ -164,6 +170,14 @@ struct sbitmap_queue { int sbitmap_init_node(struct sbitmap *sb, unsigned int depth, int shift, gfp_t flags, int node, bool round_robin, bool alloc_hint); +/* sbitmap internal helper */ +static inline unsigned int __map_depth(const struct sbitmap *sb, int index) +{ + if (index == sb->map_nr - 1) + return sb->depth - (index << sb->shift); + return 1U << sb->shift; +} + /** * sbitmap_free() - Free memory used by a &struct sbitmap. * @sb: Bitmap to free. @@ -171,7 +185,7 @@ int sbitmap_init_node(struct sbitmap *sb, unsigned int depth, int shift, static inline void sbitmap_free(struct sbitmap *sb) { free_percpu(sb->alloc_hint); - kfree(sb->map); + kvfree(sb->map); sb->map = NULL; } @@ -196,23 +210,6 @@ void sbitmap_resize(struct sbitmap *sb, unsigned int depth); int sbitmap_get(struct sbitmap *sb); /** - * sbitmap_get_shallow() - Try to allocate a free bit from a &struct sbitmap, - * limiting the depth used from each word. - * @sb: Bitmap to allocate from. - * @shallow_depth: The maximum number of bits to allocate from a single word. - * - * This rather specific operation allows for having multiple users with - * different allocation limits. E.g., there can be a high-priority class that - * uses sbitmap_get() and a low-priority class that uses sbitmap_get_shallow() - * with a @shallow_depth of (1 << (@sb->shift - 1)). Then, the low-priority - * class can only allocate half of the total bits in the bitmap, preventing it - * from starving out the high-priority class. - * - * Return: Non-negative allocated bit number if successful, -1 otherwise. - */ -int sbitmap_get_shallow(struct sbitmap *sb, unsigned long shallow_depth); - -/** * sbitmap_any_bit_set() - Check for a set bit in a &struct sbitmap. * @sb: Bitmap to check. * @@ -251,7 +248,7 @@ static inline void __sbitmap_for_each_set(struct sbitmap *sb, while (scanned < sb->depth) { unsigned long word; unsigned int depth = min_t(unsigned int, - sb->map[index].depth - nr, + __map_depth(sb, index) - nr, sb->depth - scanned); scanned += depth; @@ -460,11 +457,11 @@ unsigned long __sbitmap_queue_get_batch(struct sbitmap_queue *sbq, int nr_tags, unsigned int *offset); /** - * __sbitmap_queue_get_shallow() - Try to allocate a free bit from a &struct + * sbitmap_queue_get_shallow() - Try to allocate a free bit from a &struct * sbitmap_queue, limiting the depth used from each word, with preemption * already disabled. * @sbq: Bitmap queue to allocate from. - * @shallow_depth: The maximum number of bits to allocate from a single word. + * @shallow_depth: The maximum number of bits to allocate from the queue. * See sbitmap_get_shallow(). * * If you call this, make sure to call sbitmap_queue_min_shallow_depth() after @@ -472,8 +469,8 @@ unsigned long __sbitmap_queue_get_batch(struct sbitmap_queue *sbq, int nr_tags, * * Return: Non-negative allocated bit number if successful, -1 otherwise. */ -int __sbitmap_queue_get_shallow(struct sbitmap_queue *sbq, - unsigned int shallow_depth); +int sbitmap_queue_get_shallow(struct sbitmap_queue *sbq, + unsigned int shallow_depth); /** * sbitmap_queue_get() - Try to allocate a free bit from a &struct @@ -496,32 +493,6 @@ static inline int sbitmap_queue_get(struct sbitmap_queue *sbq, } /** - * sbitmap_queue_get_shallow() - Try to allocate a free bit from a &struct - * sbitmap_queue, limiting the depth used from each word. - * @sbq: Bitmap queue to allocate from. - * @cpu: Output parameter; will contain the CPU we ran on (e.g., to be passed to - * sbitmap_queue_clear()). - * @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, - unsigned int *cpu, - unsigned int shallow_depth) -{ - int nr; - - *cpu = get_cpu(); - nr = __sbitmap_queue_get_shallow(sbq, shallow_depth); - put_cpu(); - return nr; -} - -/** * sbitmap_queue_min_shallow_depth() - Inform a &struct sbitmap_queue of the * minimum shallow depth that will be used. * @sbq: Bitmap queue in question. @@ -576,6 +547,8 @@ static inline void sbq_index_atomic_inc(atomic_t *index) * sbitmap_queue. * @sbq: Bitmap queue to wait on. * @wait_index: A counter per "user" of @sbq. + * + * Return: Next wait queue to be used */ static inline struct sbq_wait_state *sbq_wait_ptr(struct sbitmap_queue *sbq, atomic_t *wait_index) @@ -598,8 +571,9 @@ 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. + * @nr: Number of bits cleared. */ -void sbitmap_queue_wake_up(struct sbitmap_queue *sbq); +void sbitmap_queue_wake_up(struct sbitmap_queue *sbq, int nr); /** * sbitmap_queue_show() - Dump &struct sbitmap_queue information to a &struct |