From: Andrey Ryabinin <aryabi...@virtuozzo.com> The minimal number of mempool elements passed to mempool_create()/mempool_resize() could be large enough to trigger high order allocation in kmalloc_node(). High order allocations are costly and/or may fail if memory is fragmented. Since we don't need the array of element pointers to be physically contiguous, use kvmalloc_node() to allocate it.
https://jira.sw.ru/browse/HCI-132 https://pmc.acronis.com/browse/VSTOR-14758 Signed-off-by: Andrey Ryabinin <aryabi...@virtuozzo.com> Reviewed-by: Kirill Tkhai <ktk...@virtuozzo.com> (cherry-picked from vz7 commit 083d46fa7553 ("mm/mempool: Use kvmalloc to allocate array of element pointers")) Signed-off-by: Andrey Zhadchenko <andrey.zhadche...@virtuozzo.com> (cherry picked from vz8 commit 50362c156f100d9ebdb1ee9c752c69107fbc7fa2) Signed-off-by: Andrey Zhadchenko <andrey.zhadche...@virtuozzo.com> --- mm/mempool.c | 12 +++++++----- 1 file changed, 7 insertions(+), 5 deletions(-) diff --git a/mm/mempool.c b/mm/mempool.c index 0b8afbe..1cd77ba 100644 --- a/mm/mempool.c +++ b/mm/mempool.c @@ -154,7 +154,7 @@ void mempool_exit(mempool_t *pool) void *element = remove_element(pool); pool->free(element, pool->pool_data); } - kfree(pool->elements); + kvfree(pool->elements); pool->elements = NULL; } EXPORT_SYMBOL(mempool_exit); @@ -188,7 +188,7 @@ int mempool_init_node(mempool_t *pool, int min_nr, mempool_alloc_t *alloc_fn, pool->free = free_fn; init_waitqueue_head(&pool->wait); - pool->elements = kmalloc_array_node(min_nr, sizeof(void *), + pool->elements = kvmalloc_node(min_nr * sizeof(void *), gfp_mask, node_id); if (!pool->elements) return -ENOMEM; @@ -301,6 +301,7 @@ int mempool_resize(mempool_t *pool, int new_min_nr) void *element; void **new_elements; unsigned long flags; + void *old_elements = NULL; BUG_ON(new_min_nr <= 0); might_sleep(); @@ -319,7 +320,7 @@ int mempool_resize(mempool_t *pool, int new_min_nr) spin_unlock_irqrestore(&pool->lock, flags); /* Grow the pool */ - new_elements = kmalloc_array(new_min_nr, sizeof(*new_elements), + new_elements = kvmalloc_array(new_min_nr, sizeof(*new_elements), GFP_KERNEL); if (!new_elements) return -ENOMEM; @@ -328,12 +329,12 @@ int mempool_resize(mempool_t *pool, int new_min_nr) if (unlikely(new_min_nr <= pool->min_nr)) { /* Raced, other resize will do our work */ spin_unlock_irqrestore(&pool->lock, flags); - kfree(new_elements); + kvfree(new_elements); goto out; } memcpy(new_elements, pool->elements, pool->curr_nr * sizeof(*new_elements)); - kfree(pool->elements); + old_elements = pool->elements; pool->elements = new_elements; pool->min_nr = new_min_nr; @@ -354,6 +355,7 @@ int mempool_resize(mempool_t *pool, int new_min_nr) out_unlock: spin_unlock_irqrestore(&pool->lock, flags); out: + kvfree(old_elements); return 0; } EXPORT_SYMBOL(mempool_resize); -- 1.8.3.1 _______________________________________________ Devel mailing list Devel@openvz.org https://lists.openvz.org/mailman/listinfo/devel
