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 <mel@csn.ul.ie>
Reviewed-by: Christoph Lameter <cl@linux-foundation.org>
Reviewed-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Reviewed-by: Pekka Enberg <penberg@cs.helsinki.fi>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Cc: Dave Hansen <dave@linux.vnet.ibm.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/include/linux/gfp.h b/include/linux/gfp.h
index 549ec55..c2d3fe0 100644
--- a/include/linux/gfp.h
+++ b/include/linux/gfp.h
@@ -185,9 +185,6 @@
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 @@
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 d58df90..bfbd95c 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -1401,6 +1401,9 @@
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.