diff options
| author |   David Rientjes <rientjes@google.com> | 2012-12-12 13:51:57 -0800 |
|---|---|---|
| committer |   Linus Torvalds <torvalds@linux-foundation.org> | 2012-12-12 17:38:34 -0800 |
| commit | 68ae564bbac8eb9ed54ddd2529b0e29ee190b355 (patch) | |
| tree | 5cef83b5fa072f62091552457e7d0319ce170b98 | |
| parent | mm: add a reminder comment for __GFP_BITS_SHIFT (diff) | |
| download | linux-dev-68ae564bbac8eb9ed54ddd2529b0e29ee190b355.tar.xz linux-dev-68ae564bbac8eb9ed54ddd2529b0e29ee190b355.zip | |
mm, memcg: avoid unnecessary function call when memcg is disabled
While profiling numa/core v16 with cgroup_disable=memory on the command
line, I noticed mem_cgroup_count_vm_event() still showed up as high as
0.60% in perftop.
This occurs because the function is called extremely often even when memcg
is disabled.
To fix this, inline the check for mem_cgroup_disabled() so we avoid the
unnecessary function call if memcg is disabled.
Signed-off-by: David Rientjes <rientjes@google.com>
Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Acked-by: Glauber Costa <glommer@parallels.com>
Acked-by: Michal Hocko <mhocko@suse.cz>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| -rw-r--r-- | include/linux/memcontrol.h | 9 | ||||
| -rw-r--r-- | mm/memcontrol.c | 6 |
2 files changed, 12 insertions, 3 deletions
diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h index 11ddc7ffeba8..e98a74c0c9c0 100644 --- a/include/linux/memcontrol.h +++ b/include/linux/memcontrol.h @@ -181,7 +181,14 @@ unsigned long mem_cgroup_soft_limit_reclaim(struct zone *zone, int order, gfp_t gfp_mask, unsigned long *total_scanned); -void mem_cgroup_count_vm_event(struct mm_struct *mm, enum vm_event_item idx); +void __mem_cgroup_count_vm_event(struct mm_struct *mm, enum vm_event_item idx); +static inline void mem_cgroup_count_vm_event(struct mm_struct *mm, + enum vm_event_item idx) +{ + if (mem_cgroup_disabled()) + return; + __mem_cgroup_count_vm_event(mm, idx); +} #ifdef CONFIG_TRANSPARENT_HUGEPAGE void mem_cgroup_split_huge_fixup(struct page *head); #endif diff --git a/mm/memcontrol.c b/mm/memcontrol.c index 49d86d06e1dd..7f0e3571df7e 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -59,6 +59,8 @@ #include <trace/events/vmscan.h> struct cgroup_subsys mem_cgroup_subsys __read_mostly; +EXPORT_SYMBOL(mem_cgroup_subsys); + #define MEM_CGROUP_RECLAIM_RETRIES 5 static struct mem_cgroup *root_mem_cgroup __read_mostly; @@ -1015,7 +1017,7 @@ void mem_cgroup_iter_break(struct mem_cgroup *root, iter != NULL; \ iter = mem_cgroup_iter(NULL, iter, NULL)) -void mem_cgroup_count_vm_event(struct mm_struct *mm, enum vm_event_item idx) +void __mem_cgroup_count_vm_event(struct mm_struct *mm, enum vm_event_item idx) { struct mem_cgroup *memcg; @@ -1040,7 +1042,7 @@ void mem_cgroup_count_vm_event(struct mm_struct *mm, enum vm_event_item idx) out: rcu_read_unlock(); } -EXPORT_SYMBOL(mem_cgroup_count_vm_event); +EXPORT_SYMBOL(__mem_cgroup_count_vm_event); /** * mem_cgroup_zone_lruvec - get the lru list vector for a zone and memcg |