memcg: get rid of memcg_create_cache_name
Instead of calling back to memcontrol.c from kmem_cache_create_memcg in
order to just create the name of a per memcg cache, let's allocate it in
place. We only need to pass the memcg name to kmem_cache_create_memcg for
that - everything else can be done in slab_common.c.
Signed-off-by: Vladimir Davydov <vdavydov@parallels.com>
Acked-by: Michal Hocko <mhocko@suse.cz>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index 971d7b6..7df7f59 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -3095,29 +3095,6 @@
return 0;
}
-char *memcg_create_cache_name(struct mem_cgroup *memcg,
- struct kmem_cache *root_cache)
-{
- static char *buf;
-
- /*
- * We need a mutex here to protect the shared buffer. Since this is
- * expected to be called only on cache creation, we can employ the
- * slab_mutex for that purpose.
- */
- lockdep_assert_held(&slab_mutex);
-
- if (!buf) {
- buf = kmalloc(NAME_MAX + 1, GFP_KERNEL);
- if (!buf)
- return NULL;
- }
-
- cgroup_name(memcg->css.cgroup, buf, NAME_MAX + 1);
- return kasprintf(GFP_KERNEL, "%s(%d:%s)", root_cache->name,
- memcg_cache_id(memcg), buf);
-}
-
int memcg_alloc_cache_params(struct mem_cgroup *memcg, struct kmem_cache *s,
struct kmem_cache *root_cache)
{
@@ -3158,6 +3135,7 @@
static void memcg_kmem_create_cache(struct mem_cgroup *memcg,
struct kmem_cache *root_cache)
{
+ static char *memcg_name_buf; /* protected by memcg_slab_mutex */
struct kmem_cache *cachep;
int id;
@@ -3173,7 +3151,14 @@
if (cache_from_memcg_idx(root_cache, id))
return;
- cachep = kmem_cache_create_memcg(memcg, root_cache);
+ if (!memcg_name_buf) {
+ memcg_name_buf = kmalloc(NAME_MAX + 1, GFP_KERNEL);
+ if (!memcg_name_buf)
+ return;
+ }
+
+ cgroup_name(memcg->css.cgroup, memcg_name_buf, NAME_MAX + 1);
+ cachep = kmem_cache_create_memcg(memcg, root_cache, memcg_name_buf);
/*
* If we could not create a memcg cache, do not complain, because
* that's not critical at all as we can always proceed with the root