From b9f00e147f27d86691f7f52a3c8126d25432477c Mon Sep 17 00:00:00 2001 From: Mel Gorman Date: Thu, 19 May 2016 17:13:24 -0700 Subject: [PATCH] mm, page_alloc: reduce branches in zone_statistics zone_statistics has more branches than it really needs to take an unlikely GFP flag into account. Reduce the number and annotate the unlikely flag. The performance difference on a page allocator microbenchmark is; 4.6.0-rc2 4.6.0-rc2 nocompound-v1r10 statbranch-v1r10 Min alloc-odr0-1 417.00 ( 0.00%) 419.00 ( -0.48%) Min alloc-odr0-2 308.00 ( 0.00%) 305.00 ( 0.97%) Min alloc-odr0-4 253.00 ( 0.00%) 250.00 ( 1.19%) Min alloc-odr0-8 221.00 ( 0.00%) 219.00 ( 0.90%) Min alloc-odr0-16 205.00 ( 0.00%) 203.00 ( 0.98%) Min alloc-odr0-32 199.00 ( 0.00%) 195.00 ( 2.01%) Min alloc-odr0-64 193.00 ( 0.00%) 191.00 ( 1.04%) Min alloc-odr0-128 191.00 ( 0.00%) 189.00 ( 1.05%) Min alloc-odr0-256 200.00 ( 0.00%) 198.00 ( 1.00%) Min alloc-odr0-512 212.00 ( 0.00%) 210.00 ( 0.94%) Min alloc-odr0-1024 219.00 ( 0.00%) 216.00 ( 1.37%) Min alloc-odr0-2048 225.00 ( 0.00%) 221.00 ( 1.78%) Min alloc-odr0-4096 231.00 ( 0.00%) 227.00 ( 1.73%) Min alloc-odr0-8192 234.00 ( 0.00%) 232.00 ( 0.85%) Min alloc-odr0-16384 234.00 ( 0.00%) 232.00 ( 0.85%) Signed-off-by: Mel Gorman Acked-by: Vlastimil Babka Cc: Jesper Dangaard Brouer Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/vmstat.c | 16 ++++++++++------ 1 file changed, 10 insertions(+), 6 deletions(-) diff --git a/mm/vmstat.c b/mm/vmstat.c index c831be32a1a3..d585de27e960 100644 --- a/mm/vmstat.c +++ b/mm/vmstat.c @@ -581,17 +581,21 @@ void drain_zonestat(struct zone *zone, struct per_cpu_pageset *pset) */ void zone_statistics(struct zone *preferred_zone, struct zone *z, gfp_t flags) { - if (z->zone_pgdat == preferred_zone->zone_pgdat) { + int local_nid = numa_node_id(); + enum zone_stat_item local_stat = NUMA_LOCAL; + + if (unlikely(flags & __GFP_OTHER_NODE)) { + local_stat = NUMA_OTHER; + local_nid = preferred_zone->node; + } + + if (z->node == local_nid) { __inc_zone_state(z, NUMA_HIT); + __inc_zone_state(z, local_stat); } else { __inc_zone_state(z, NUMA_MISS); __inc_zone_state(preferred_zone, NUMA_FOREIGN); } - if (z->node == ((flags & __GFP_OTHER_NODE) ? - preferred_zone->node : numa_node_id())) - __inc_zone_state(z, NUMA_LOCAL); - else - __inc_zone_state(z, NUMA_OTHER); } /* -- 2.39.5