From aff622495c9a0b56148192e53bdec539f5e147f2 Mon Sep 17 00:00:00 2001 From: Rik van Riel Date: Wed, 21 Mar 2012 16:33:52 -0700 Subject: vmscan: only defer compaction for failed order and higher Currently a failed order-9 (transparent hugepage) compaction can lead to memory compaction being temporarily disabled for a memory zone. Even if we only need compaction for an order 2 allocation, eg. for jumbo frames networking. The fix is relatively straightforward: keep track of the highest order at which compaction is succeeding, and only defer compaction for orders at which compaction is failing. Signed-off-by: Rik van Riel Cc: Andrea Arcangeli Acked-by: Mel Gorman Cc: Johannes Weiner Cc: Minchan Kim Cc: KOSAKI Motohiro Cc: Hillf Danton Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/page_alloc.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) (limited to 'mm/page_alloc.c') diff --git a/mm/page_alloc.c b/mm/page_alloc.c index a13ded1938f0..572b93ea475c 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -1990,7 +1990,7 @@ __alloc_pages_direct_compact(gfp_t gfp_mask, unsigned int order, if (!order) return NULL; - if (compaction_deferred(preferred_zone)) { + if (compaction_deferred(preferred_zone, order)) { *deferred_compaction = true; return NULL; } @@ -2012,6 +2012,8 @@ __alloc_pages_direct_compact(gfp_t gfp_mask, unsigned int order, if (page) { preferred_zone->compact_considered = 0; preferred_zone->compact_defer_shift = 0; + if (order >= preferred_zone->compact_order_failed) + preferred_zone->compact_order_failed = order + 1; count_vm_event(COMPACTSUCCESS); return page; } @@ -2028,7 +2030,7 @@ __alloc_pages_direct_compact(gfp_t gfp_mask, unsigned int order, * defer if the failure was a sync compaction failure. */ if (sync_migration) - defer_compaction(preferred_zone); + defer_compaction(preferred_zone, order); cond_resched(); } -- cgit v1.2.3