From 908ee0f122bf2a67414854af5b90c6621d186a71 Mon Sep 17 00:00:00 2001 From: Christoph Lameter Date: Mon, 6 Dec 2010 11:40:02 -0600 Subject: [PATCH] vmstat: Use this_cpu_inc_return for vm statistics this_cpu_inc_return() saves us a memory access there. Code size does not change. V1->V2: - Fixed the location of the __per_cpu pointer attributes - Sparse checked V2->V3: - Move fixes to __percpu attribute usage to earlier patch Reviewed-by: Pekka Enberg Acked-by: H. Peter Anvin Signed-off-by: Christoph Lameter Signed-off-by: Tejun Heo --- mm/vmstat.c | 8 ++------ 1 file changed, 2 insertions(+), 6 deletions(-) diff --git a/mm/vmstat.c b/mm/vmstat.c index 3ad909d9600f..f9a7bc89fd10 100644 --- a/mm/vmstat.c +++ b/mm/vmstat.c @@ -227,9 +227,7 @@ void __inc_zone_state(struct zone *zone, enum zone_stat_item item) s8 __percpu *p = pcp->vm_stat_diff + item; s8 v, t; - __this_cpu_inc(*p); - - v = __this_cpu_read(*p); + v = __this_cpu_inc_return(*p); t = __this_cpu_read(pcp->stat_threshold); if (unlikely(v > t)) { s8 overstep = t >> 1; @@ -251,9 +249,7 @@ void __dec_zone_state(struct zone *zone, enum zone_stat_item item) s8 __percpu *p = pcp->vm_stat_diff + item; s8 v, t; - __this_cpu_dec(*p); - - v = __this_cpu_read(*p); + v = __this_cpu_dec_return(*p); t = __this_cpu_read(pcp->stat_threshold); if (unlikely(v < - t)) { s8 overstep = t >> 1;