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 Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** 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 -- To unsubscribe from this list: send the line "unsubscribe mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html