summaryrefslogtreecommitdiffstats
path: root/mm
diff options
context:
space:
mode:
authorDavid Rientjes <rientjes@google.com>2012-12-12 13:51:57 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2012-12-12 17:38:34 -0800
commit68ae564bbac8eb9ed54ddd2529b0e29ee190b355 (patch)
tree5cef83b5fa072f62091552457e7d0319ce170b98 /mm
parent05b0afd73d04109d87f00ccd39f099e217c37263 (diff)
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>
Diffstat (limited to 'mm')
-rw-r--r--mm/memcontrol.c6
1 files changed, 4 insertions, 2 deletions
diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index 49d86d06e1d..7f0e3571df7 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