From addb9efebb2ee2202d324e75b593b39868528f68 Mon Sep 17 00:00:00 2001 From: KAMEZAWA Hiroyuki Date: Sat, 18 Oct 2008 20:28:10 -0700 Subject: [PATCH] memcg: optimize per-cpu statistics Some obvious optimization to memcg. I found mem_cgroup_charge_statistics() is a little big (in object) and does unnecessary address calclation. This patch is for optimization to reduce the size of this function. And res_counter_charge() is 'likely' to succeed. Signed-off-by: KAMEZAWA Hiroyuki Acked-by: Balbir Singh Cc: Daisuke Nishimura Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/memcontrol.c | 18 ++++++++++-------- 1 file changed, 10 insertions(+), 8 deletions(-) diff --git a/mm/memcontrol.c b/mm/memcontrol.c index 6f8b5b3b38b2..10846b9656aa 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -66,11 +66,10 @@ struct mem_cgroup_stat { /* * For accounting under irq disable, no need for increment preempt count. */ -static void __mem_cgroup_stat_add_safe(struct mem_cgroup_stat *stat, +static inline void __mem_cgroup_stat_add_safe(struct mem_cgroup_stat_cpu *stat, enum mem_cgroup_stat_index idx, int val) { - int cpu = smp_processor_id(); - stat->cpustat[cpu].count[idx] += val; + stat->count[idx] += val; } static s64 mem_cgroup_read_stat(struct mem_cgroup_stat *stat, @@ -190,18 +189,21 @@ static void mem_cgroup_charge_statistics(struct mem_cgroup *mem, int flags, { int val = (charge)? 1 : -1; struct mem_cgroup_stat *stat = &mem->stat; + struct mem_cgroup_stat_cpu *cpustat; VM_BUG_ON(!irqs_disabled()); + + cpustat = &stat->cpustat[smp_processor_id()]; if (flags & PAGE_CGROUP_FLAG_CACHE) - __mem_cgroup_stat_add_safe(stat, MEM_CGROUP_STAT_CACHE, val); + __mem_cgroup_stat_add_safe(cpustat, MEM_CGROUP_STAT_CACHE, val); else - __mem_cgroup_stat_add_safe(stat, MEM_CGROUP_STAT_RSS, val); + __mem_cgroup_stat_add_safe(cpustat, MEM_CGROUP_STAT_RSS, val); if (charge) - __mem_cgroup_stat_add_safe(stat, + __mem_cgroup_stat_add_safe(cpustat, MEM_CGROUP_STAT_PGPGIN_COUNT, 1); else - __mem_cgroup_stat_add_safe(stat, + __mem_cgroup_stat_add_safe(cpustat, MEM_CGROUP_STAT_PGPGOUT_COUNT, 1); } @@ -558,7 +560,7 @@ static int mem_cgroup_charge_common(struct page *page, struct mm_struct *mm, css_get(&memcg->css); } - while (res_counter_charge(&mem->res, PAGE_SIZE)) { + while (unlikely(res_counter_charge(&mem->res, PAGE_SIZE))) { if (!(gfp_mask & __GFP_WAIT)) goto out; -- 2.20.1