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 <kamezawa.hiroyu@jp.fujitsu.com>
Acked-by: Balbir Singh <balbir@linux.vnet.ibm.com>
Cc: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
KAMEZAWA Hiroyuki 2008-10-18 20:28:10 -07:00 committed by Linus Torvalds
parent 5b4e655e94
commit addb9efebb

View File

@ -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;