diff options
author | Kent Overstreet <kent.overstreet@gmail.com> | 2015-05-04 16:52:20 -0700 |
---|---|---|
committer | Jens Axboe <axboe@kernel.dk> | 2018-05-14 13:14:23 -0600 |
commit | c1a67fefd0546a5552289c65fe31b1d60e64b643 (patch) | |
tree | e96bfb877d770c45e4b7a58d251edf3808ae5d32 /mm/mempool.c | |
parent | c854ab5773be1c1a0d3cef0c3a3261f2c48ab7f8 (diff) | |
download | lwn-c1a67fefd0546a5552289c65fe31b1d60e64b643.tar.gz lwn-c1a67fefd0546a5552289c65fe31b1d60e64b643.zip |
mempool: Add mempool_init()/mempool_exit()
Allows mempools to be embedded in other structs, getting rid of a
pointer indirection from allocation fastpaths.
mempool_exit() is safe to call on an uninitialized but zeroed mempool.
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Diffstat (limited to 'mm/mempool.c')
-rw-r--r-- | mm/mempool.c | 108 |
1 files changed, 81 insertions, 27 deletions
diff --git a/mm/mempool.c b/mm/mempool.c index 5c9dce34719b..b54f2c20e5e0 100644 --- a/mm/mempool.c +++ b/mm/mempool.c @@ -138,6 +138,28 @@ static void *remove_element(mempool_t *pool, gfp_t flags) } /** + * mempool_exit - exit a mempool initialized with mempool_init() + * @pool: pointer to the memory pool which was initialized with + * mempool_init(). + * + * Free all reserved elements in @pool and @pool itself. This function + * only sleeps if the free_fn() function sleeps. + * + * May be called on a zeroed but uninitialized mempool (i.e. allocated with + * kzalloc()). + */ +void mempool_exit(mempool_t *pool) +{ + while (pool->curr_nr) { + void *element = remove_element(pool, GFP_KERNEL); + pool->free(element, pool->pool_data); + } + kfree(pool->elements); + pool->elements = NULL; +} +EXPORT_SYMBOL(mempool_exit); + +/** * mempool_destroy - deallocate a memory pool * @pool: pointer to the memory pool which was allocated via * mempool_create(). @@ -150,15 +172,65 @@ void mempool_destroy(mempool_t *pool) if (unlikely(!pool)) return; - while (pool->curr_nr) { - void *element = remove_element(pool, GFP_KERNEL); - pool->free(element, pool->pool_data); - } - kfree(pool->elements); + mempool_exit(pool); kfree(pool); } EXPORT_SYMBOL(mempool_destroy); +int mempool_init_node(mempool_t *pool, int min_nr, mempool_alloc_t *alloc_fn, + mempool_free_t *free_fn, void *pool_data, + gfp_t gfp_mask, int node_id) +{ + spin_lock_init(&pool->lock); + pool->min_nr = min_nr; + pool->pool_data = pool_data; + pool->alloc = alloc_fn; + pool->free = free_fn; + init_waitqueue_head(&pool->wait); + + pool->elements = kmalloc_array_node(min_nr, sizeof(void *), + gfp_mask, node_id); + if (!pool->elements) + return -ENOMEM; + + /* + * First pre-allocate the guaranteed number of buffers. + */ + while (pool->curr_nr < pool->min_nr) { + void *element; + + element = pool->alloc(gfp_mask, pool->pool_data); + if (unlikely(!element)) { + mempool_exit(pool); + return -ENOMEM; + } + add_element(pool, element); + } + + return 0; +} +EXPORT_SYMBOL(mempool_init_node); + +/** + * mempool_init - initialize a memory pool + * @min_nr: the minimum number of elements guaranteed to be + * allocated for this pool. + * @alloc_fn: user-defined element-allocation function. + * @free_fn: user-defined element-freeing function. + * @pool_data: optional private data available to the user-defined functions. + * + * Like mempool_create(), but initializes the pool in (i.e. embedded in another + * structure). + */ +int mempool_init(mempool_t *pool, int min_nr, mempool_alloc_t *alloc_fn, + mempool_free_t *free_fn, void *pool_data) +{ + return mempool_init_node(pool, min_nr, alloc_fn, free_fn, + pool_data, GFP_KERNEL, NUMA_NO_NODE); + +} +EXPORT_SYMBOL(mempool_init); + /** * mempool_create - create a memory pool * @min_nr: the minimum number of elements guaranteed to be @@ -186,35 +258,17 @@ mempool_t *mempool_create_node(int min_nr, mempool_alloc_t *alloc_fn, gfp_t gfp_mask, int node_id) { mempool_t *pool; + pool = kzalloc_node(sizeof(*pool), gfp_mask, node_id); if (!pool) return NULL; - pool->elements = kmalloc_array_node(min_nr, sizeof(void *), - gfp_mask, node_id); - if (!pool->elements) { + + if (mempool_init_node(pool, min_nr, alloc_fn, free_fn, pool_data, + gfp_mask, node_id)) { kfree(pool); return NULL; } - spin_lock_init(&pool->lock); - pool->min_nr = min_nr; - pool->pool_data = pool_data; - init_waitqueue_head(&pool->wait); - pool->alloc = alloc_fn; - pool->free = free_fn; - /* - * First pre-allocate the guaranteed number of buffers. - */ - while (pool->curr_nr < pool->min_nr) { - void *element; - - element = pool->alloc(gfp_mask, pool->pool_data); - if (unlikely(!element)) { - mempool_destroy(pool); - return NULL; - } - add_element(pool, element); - } return pool; } EXPORT_SYMBOL(mempool_create_node); |