From deba04872be44e1c005364c276495a3b425dfbe6 Mon Sep 17 00:00:00 2001 From: Vlastimil Babka Date: Thu, 6 Aug 2020 23:25:16 -0700 Subject: mm, page_alloc: use unlikely() in task_capc() Hugh noted that task_capc() could use unlikely(), as most of the time there is no capture in progress and we are in page freeing hot path. Indeed adding unlikely() produces assembly that better matches the assumption and moves all the tests away from the hot path. I have also noticed that we don't need to test for cc->direct_compaction as the only place we set current->task_capture is compact_zone_order() which also always sets cc->direct_compaction true. Suggested-by: Hugh Dickins Signed-off-by: Vlastimil Babka Signed-off-by: Andrew Morton Acked-by: Hugh Dickins Acked-by: Mel Gorman Cc: Alex Shi Cc: Li Wang Link: http://lkml.kernel.org/r/4a24f7af-3aa5-6e80-4ae6-8f253b562039@suse.cz Signed-off-by: Linus Torvalds --- mm/page_alloc.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-) (limited to 'mm/page_alloc.c') diff --git a/mm/page_alloc.c b/mm/page_alloc.c index f49de9e97bf2..ce2409ee2144 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -813,11 +813,10 @@ static inline struct capture_control *task_capc(struct zone *zone) { struct capture_control *capc = current->capture_control; - return capc && + return unlikely(capc) && !(current->flags & PF_KTHREAD) && !capc->page && - capc->cc->zone == zone && - capc->cc->direct_compaction ? capc : NULL; + capc->cc->zone == zone ? capc : NULL; } static inline bool -- cgit v1.2.3