From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Sun, 5 Oct 2008 03:27:00 +0100 (BST) From: Hugh Dickins Subject: [PATCH next 2/3] slub defrag: dma_kmalloc_cache add_tail In-Reply-To: Message-ID: References: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-linux-mm@kvack.org Return-Path: To: Christoph Lameter Cc: Pekka Enberg , Andrew Morton , linux-mm@kvack.org List-ID: Why did that slowdown from mispinned pages manifest only on the G5? Because something in my x86_32 and x86_64 configs (CONFIG_BLK_DEV_SR I believe) is giving me a kmalloc_dma-512 cache, and dma_kmalloc_cache() had not been updated to satisfy the assumption in kmem_cache_defrag(), that defragmentable caches come first in the list. So, any DMAable cache was preventing all slub defragmentation: which looks like it's not been getting the testing exposure it deserves. Signed-off-by: Hugh Dickins --- mm/slub.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- 2.6.27-rc7-mmotm/mm/slub.c 2008-09-26 13:18:53.000000000 +0100 +++ linux/mm/slub.c 2008-10-04 20:10:46.000000000 +0100 @@ -2636,7 +2636,7 @@ static noinline struct kmem_cache *dma_k goto unlock_out; } - list_add(&s->list, &slab_caches); + list_add_tail(&s->list, &slab_caches); kmalloc_caches_dma[index] = s; schedule_work(&sysfs_add_work); -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org