diff options
authorVladimir Davydov <vdavydov@parallels.com>2014-10-09 15:28:59 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2014-10-09 22:26:00 -0400
commitcf2b8fbf1d2f7ba07999e97685563c94483d33d6 (patch)
parentb70a2a21dc9d4ad455931b53131a0cb4fc01fafe (diff)
memcg: zap memcg_can_account_kmem
memcg_can_account_kmem() returns true iff !mem_cgroup_disabled() && !mem_cgroup_is_root(memcg) && memcg_kmem_is_active(memcg); To begin with the !mem_cgroup_is_root(memcg) check is useless, because one can't enable kmem accounting for the root cgroup (mem_cgroup_write() returns EINVAL on an attempt to set the limit on the root cgroup). Furthermore, the !mem_cgroup_disabled() check also seems to be redundant. The point is memcg_can_account_kmem() is called from three places: mem_cgroup_salbinfo_read(), __memcg_kmem_get_cache(), and __memcg_kmem_newpage_charge(). The latter two functions are only invoked if memcg_kmem_enabled() returns true, which implies that the memory cgroup subsystem is enabled. And mem_cgroup_slabinfo_read() shows the output of memory.kmem.slabinfo, which won't exist if the memory cgroup is completely disabled. So let's substitute all the calls to memcg_can_account_kmem() with plain memcg_kmem_is_active(), and kill the former. Signed-off-by: Vladimir Davydov <vdavydov@parallels.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Cc: Michal Hocko <mhocko@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
1 files changed, 3 insertions, 9 deletions
diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index c86cc442ada4..23976fd885fd 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -2762,12 +2762,6 @@ static DEFINE_MUTEX(memcg_slab_mutex);
static DEFINE_MUTEX(activate_kmem_mutex);
-static inline bool memcg_can_account_kmem(struct mem_cgroup *memcg)
- return !mem_cgroup_disabled() && !mem_cgroup_is_root(memcg) &&
- memcg_kmem_is_active(memcg);
* This is a bit cumbersome, but it is rarely used and avoids a backpointer
* in the memcg_cache_params struct.
@@ -2787,7 +2781,7 @@ static int mem_cgroup_slabinfo_read(struct seq_file *m, void *v)
struct mem_cgroup *memcg = mem_cgroup_from_css(seq_css(m));
struct memcg_cache_params *params;
- if (!memcg_can_account_kmem(memcg))
+ if (!memcg_kmem_is_active(memcg))
return -EIO;
@@ -3164,7 +3158,7 @@ struct kmem_cache *__memcg_kmem_get_cache(struct kmem_cache *cachep,
memcg = mem_cgroup_from_task(rcu_dereference(current->mm->owner));
- if (!memcg_can_account_kmem(memcg))
+ if (!memcg_kmem_is_active(memcg))
goto out;
memcg_cachep = cache_from_memcg_idx(cachep, memcg_cache_id(memcg));
@@ -3249,7 +3243,7 @@ __memcg_kmem_newpage_charge(gfp_t gfp, struct mem_cgroup **_memcg, int order)
memcg = get_mem_cgroup_from_mm(current->mm);
- if (!memcg_can_account_kmem(memcg)) {
+ if (!memcg_kmem_is_active(memcg)) {
return true;