From b3c466ce512923298ae8c0121d3e9f397a3f1210 Mon Sep 17 00:00:00 2001 From: Mel Gorman Date: Tue, 16 Jun 2009 15:31:53 -0700 Subject: [PATCH] page allocator: do not sanity check order in the fast path No user of the allocator API should be passing in an order >= MAX_ORDER but we check for it on each and every allocation. Delete this check and make it a VM_BUG_ON check further down the call path. [akpm@linux-foundation.org: s/VM_BUG_ON/WARN_ON_ONCE/] Signed-off-by: Mel Gorman Reviewed-by: Christoph Lameter Reviewed-by: KOSAKI Motohiro Reviewed-by: Pekka Enberg Cc: Peter Zijlstra Cc: Nick Piggin Cc: Dave Hansen Cc: Lee Schermerhorn Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/gfp.h | 6 ------ mm/page_alloc.c | 3 +++ 2 files changed, 3 insertions(+), 6 deletions(-) diff --git a/include/linux/gfp.h b/include/linux/gfp.h index 549ec558310..c2d3fe03b5d 100644 --- a/include/linux/gfp.h +++ b/include/linux/gfp.h @@ -185,9 +185,6 @@ __alloc_pages(gfp_t gfp_mask, unsigned int order, static inline struct page *alloc_pages_node(int nid, gfp_t gfp_mask, unsigned int order) { - if (unlikely(order >= MAX_ORDER)) - return NULL; - /* Unknown node is current node */ if (nid < 0) nid = numa_node_id(); @@ -201,9 +198,6 @@ extern struct page *alloc_pages_current(gfp_t gfp_mask, unsigned order); static inline struct page * alloc_pages(gfp_t gfp_mask, unsigned int order) { - if (unlikely(order >= MAX_ORDER)) - return NULL; - return alloc_pages_current(gfp_mask, order); } extern struct page *alloc_page_vma(gfp_t gfp_mask, diff --git a/mm/page_alloc.c b/mm/page_alloc.c index d58df903150..bfbd95c0610 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -1401,6 +1401,9 @@ get_page_from_freelist(gfp_t gfp_mask, nodemask_t *nodemask, unsigned int order, classzone_idx = zone_idx(preferred_zone); + if (WARN_ON_ONCE(order >= MAX_ORDER)) + return NULL; + zonelist_scan: /* * Scan zonelist, looking for a zone with enough free. -- 2.20.1