From: Michal Hocko <mhocko@xxxxxxxx> jbd2_alloc is explicit about its allocation preferences wrt. the allocation size. Sub page allocations go to the slab allocator and larger are using either the page allocator or vmalloc. This is all good but the logic is unnecessarily complex. Requests larger than order-3 are doing the vmalloc directly while smaller go to the page allocator with __GFP_REPEAT. The flag doesn't do anything useful for those because they are smaller than PAGE_ALLOC_COSTLY_ORDER. Let's simplify the code flow and use kmalloc for sub-page requests and the page allocator for others with fallback to vmalloc if the allocation fails. Cc: "Theodore Ts'o" <tytso@xxxxxxx> Signed-off-by: Michal Hocko <mhocko@xxxxxxxx> --- fs/jbd2/journal.c | 15 ++++++--------- 1 file changed, 6 insertions(+), 9 deletions(-) diff --git a/fs/jbd2/journal.c b/fs/jbd2/journal.c index 81e622681c82..630abbfa4b61 100644 --- a/fs/jbd2/journal.c +++ b/fs/jbd2/journal.c @@ -2299,18 +2299,15 @@ void *jbd2_alloc(size_t size, gfp_t flags) BUG_ON(size & (size-1)); /* Must be a power of 2 */ - flags |= __GFP_REPEAT; - if (size == PAGE_SIZE) - ptr = (void *)__get_free_pages(flags, 0); - else if (size > PAGE_SIZE) { + if (size < PAGE_SIZE) + ptr = kmem_cache_alloc(get_slab(size), flags); + else { int order = get_order(size); - if (order < 3) - ptr = (void *)__get_free_pages(flags, order); - else + ptr = (void *)__get_free_pages(flags, order); + if (!ptr) ptr = vmalloc(size); - } else - ptr = kmem_cache_alloc(get_slab(size), flags); + } /* Check alignment; SLUB has gotten this wrong in the past, * and this can lead to user data corruption! */ -- 2.6.1 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx"> email@xxxxxxxxx </a>