+ memcg-memcg_kmem_create_cache-make-memcg_name_buf.patch added to -mm tree

+ memcg-memcg_kmem_create_cache-make-memcg_name_buf.patch added to -mm tree

[akpm]

Subject: + memcg-memcg_kmem_create_cache-make-memcg_name_buf.patch added to -mm tree
To: vdavydov@parallels.com,hannes@cmpxchg.org,mhocko@suse.cz
From: akpm@linux-foundation.org
Date: Thu, 08 May 2014 15:08:56 -0700


The patch titled
     Subject: memcg: memcg_kmem_create_cache: make memcg_name_buf statically allocated
has been added to the -mm tree.  Its filename is
     memcg-memcg_kmem_create_cache-make-memcg_name_buf.patch

This patch should soon appear at
    http://ozlabs.org/~akpm/mmots/broken-out/memcg-memcg_kmem_create_cache-make-memcg_name_buf.patch
and later at
    http://ozlabs.org/~akpm/mmotm/broken-out/memcg-memcg_kmem_create_cache-make-memcg_name_buf.patch

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------------------------------------------------------
From: Vladimir Davydov <vdavydov@parallels.com>
Subject: memcg: memcg_kmem_create_cache: make memcg_name_buf statically allocated

It isn't worth complicating the code by allocating it on the first access,
because it only takes 256 bytes.

Signed-off-by: Vladimir Davydov <vdavydov@parallels.com>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/memcontrol.c |    9 ++-------
 1 file changed, 2 insertions(+), 7 deletions(-)

diff -puN mm/memcontrol.c~memcg-memcg_kmem_create_cache-make-memcg_name_buf mm/memcontrol.c
--- a/mm/memcontrol.c~memcg-memcg_kmem_create_cache-make-memcg_name_buf
+++ a/mm/memcontrol.c
@@ -3134,7 +3134,8 @@ void memcg_free_cache_params(struct kmem
 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 */
+	static char memcg_name_buf[NAME_MAX + 1]; /* protected by
+						     memcg_slab_mutex */
 	struct kmem_cache *cachep;
 	int id;
 
@@ -3150,12 +3151,6 @@ static void memcg_kmem_create_cache(stru
 	if (cache_from_memcg_idx(root_cache, id))
 		return;
 
-	if (!memcg_name_buf) {
-		memcg_name_buf = kmalloc(NAME_MAX + 1, GFP_KERNEL);
-		if (!memcg_name_buf)
-			return;
-	}