From 0565d317768cc66b13e37184f29d9f270c2886dc Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Tue, 10 Jan 2012 15:08:26 -0800 Subject: [PATCH] mempool: drop unnecessary and incorrect BUG_ON() from mempool_destroy() mempool_destroy() is a thin wrapper around free_pool(). The only thing it adds is BUG_ON(pool->curr_nr != pool->min_nr). The intention seems to be to enforce that all allocated elements are freed; however, the BUG_ON() can't achieve that (it doesn't know anything about objects above min_nr) and incorrect as mempool_resize() is allowed to leave the pool extended but not filled. Furthermore, panicking is way worse than any memory leak and there are better debug tools to track memory leaks. Drop the BUG_ON() from mempool_destory() and as that leaves the function identical to free_pool(), replace it. Signed-off-by: Tejun Heo Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/mempool.c | 30 +++++++++++------------------- 1 file changed, 11 insertions(+), 19 deletions(-) diff --git a/mm/mempool.c b/mm/mempool.c index 11f0d0a5e0f8..e3a802a0cea0 100644 --- a/mm/mempool.c +++ b/mm/mempool.c @@ -27,7 +27,15 @@ static void *remove_element(mempool_t *pool) return pool->elements[--pool->curr_nr]; } -static void free_pool(mempool_t *pool) +/** + * mempool_destroy - deallocate a memory pool + * @pool: pointer to the memory pool which was allocated via + * mempool_create(). + * + * Free all reserved elements in @pool and @pool itself. This function + * only sleeps if the free_fn() function sleeps. + */ +void mempool_destroy(mempool_t *pool) { while (pool->curr_nr) { void *element = remove_element(pool); @@ -36,6 +44,7 @@ static void free_pool(mempool_t *pool) kfree(pool->elements); kfree(pool); } +EXPORT_SYMBOL(mempool_destroy); /** * mempool_create - create a memory pool @@ -86,7 +95,7 @@ mempool_t *mempool_create_node(int min_nr, mempool_alloc_t *alloc_fn, element = pool->alloc(GFP_KERNEL, pool->pool_data); if (unlikely(!element)) { - free_pool(pool); + mempool_destroy(pool); return NULL; } add_element(pool, element); @@ -171,23 +180,6 @@ int mempool_resize(mempool_t *pool, int new_min_nr, gfp_t gfp_mask) } EXPORT_SYMBOL(mempool_resize); -/** - * mempool_destroy - deallocate a memory pool - * @pool: pointer to the memory pool which was allocated via - * mempool_create(). - * - * this function only sleeps if the free_fn() function sleeps. The caller - * has to guarantee that all elements have been returned to the pool (ie: - * freed) prior to calling mempool_destroy(). - */ -void mempool_destroy(mempool_t *pool) -{ - /* Check for outstanding elements */ - BUG_ON(pool->curr_nr != pool->min_nr); - free_pool(pool); -} -EXPORT_SYMBOL(mempool_destroy); - /** * mempool_alloc - allocate an element from a specific memory pool * @pool: pointer to the memory pool which was allocated via