The patch titled
page allocator: do not sanity check order in the fast path
has been added to the -mm tree. Its filename is
page-allocator-do-not-sanity-check-order-in-the-fast-path.patch
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*** Remember to use Documentation/SubmitChecklist when testing your code ***
See http://userweb.kernel.org/~akpm/stuff/added-to-mm.txt to find
out what to do about this
The current -mm tree may be found at http://userweb.kernel.org/~akpm/mmotm/
------------------------------------------------------
Subject: page allocator: do not sanity check order in the fast path
From: Mel Gorman <mel@xxxxxxxxx>
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.
Signed-off-by: Mel Gorman <mel@xxxxxxxxx>
Reviewed-by: Christoph Lameter <cl@xxxxxxxxxxxxxxxxxxxx>
Reviewed-by: KOSAKI Motohiro <kosaki.motohiro@xxxxxxxxxxxxxx>
Reviewed-by: Pekka Enberg <penberg@xxxxxxxxxxxxxx>
Cc: Peter Zijlstra <a.p.zijlstra@xxxxxxxxx>
Cc: Nick Piggin <nickpiggin@xxxxxxxxxxxx>
Cc: Dave Hansen <dave@xxxxxxxxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
include/linux/gfp.h | 6 ------
mm/page_alloc.c | 2 ++
2 files changed, 2 insertions(+), 6 deletions(-)
diff -puN include/linux/gfp.h~page-allocator-do-not-sanity-check-order-in-the-fast-path include/linux/gfp.h
--- a/include/linux/gfp.h~page-allocator-do-not-sanity-check-order-in-the-fast-path
+++ a/include/linux/gfp.h
@@ -182,9 +182,6 @@ __alloc_pages(gfp_t gfp_mask, unsigned i
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();
@@ -198,9 +195,6 @@ extern struct page *alloc_pages_current(
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 -puN mm/page_alloc.c~page-allocator-do-not-sanity-check-order-in-the-fast-path mm/page_alloc.c
--- a/mm/page_alloc.c~page-allocator-do-not-sanity-check-order-in-the-fast-path
+++ a/mm/page_alloc.c
@@ -1405,6 +1405,8 @@ get_page_from_freelist(gfp_t gfp_mask, n
classzone_idx = zone_idx(preferred_zone);
+ VM_BUG_ON(order >= MAX_ORDER);
+
zonelist_scan:
/*
* Scan zonelist, looking for a zone with enough free.
_
Patches currently in -mm which might be from mel@xxxxxxxxx are
vmscan-low-order-lumpy-reclaim-also-should-use-pageout_io_sync.patch
page-allocator-replace-__alloc_pages_internal-with-__alloc_pages_nodemask.patch
page-allocator-do-not-sanity-check-order-in-the-fast-path.patch
page-allocator-do-not-sanity-check-order-in-the-fast-path-fix.patch
page-allocator-do-not-check-numa-node-id-when-the-caller-knows-the-node-is-valid.patch
page-allocator-check-only-once-if-the-zonelist-is-suitable-for-the-allocation.patch
page-allocator-break-up-the-allocator-entry-point-into-fast-and-slow-paths.patch
page-allocator-move-check-for-disabled-anti-fragmentation-out-of-fastpath.patch
page-allocator-calculate-the-preferred-zone-for-allocation-only-once.patch
page-allocator-calculate-the-preferred-zone-for-allocation-only-once-fix.patch
page-allocator-calculate-the-migratetype-for-allocation-only-once.patch
page-allocator-calculate-the-alloc_flags-for-allocation-only-once.patch
page-allocator-remove-a-branch-by-assuming-__gfp_high-==-alloc_high.patch
page-allocator-inline-__rmqueue_smallest.patch
page-allocator-inline-buffered_rmqueue.patch
page-allocator-inline-__rmqueue_fallback.patch
page-allocator-do-not-call-get_pageblock_migratetype-more-than-necessary.patch
page-allocator-do-not-disable-interrupts-in-free_page_mlock.patch
page-allocator-do-not-setup-zonelist-cache-when-there-is-only-one-node.patch
page-allocator-do-not-check-for-compound-pages-during-the-page-allocator-sanity-checks.patch
page-allocator-use-allocation-flags-as-an-index-to-the-zone-watermark.patch
page-allocator-update-nr_free_pages-only-as-necessary.patch
page-allocator-get-the-pageblock-migratetype-without-disabling-interrupts.patch
page-allocator-use-a-pre-calculated-value-instead-of-num_online_nodes-in-fast-paths.patch
page-allocator-slab-use-nr_online_nodes-to-check-for-a-numa-platform.patch
add-debugging-aid-for-memory-initialisation-problems.patch
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