path: root/init
diff options
authorGlauber Costa <glommer@parallels.com>2012-12-18 14:22:40 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2012-12-18 15:02:14 -0800
commitd7f25f8a2f81252d1ac134470ba1d0a287cf8fcd (patch)
treeecde8b5d98762e15a6fa1984d098ddf86646942b /init
parent55007d849759252ddd573aeb36143b947202d509 (diff)
memcg: infrastructure to match an allocation to the right cache
The page allocator is able to bind a page to a memcg when it is allocated. But for the caches, we'd like to have as many objects as possible in a page belonging to the same cache. This is done in this patch by calling memcg_kmem_get_cache in the beginning of every allocation function. This function is patched out by static branches when kernel memory controller is not being used. It assumes that the task allocating, which determines the memcg in the page allocator, belongs to the same cgroup throughout the whole process. Misaccounting can happen if the task calls memcg_kmem_get_cache() while belonging to a cgroup, and later on changes. This is considered acceptable, and should only happen upon task migration. Before the cache is created by the memcg core, there is also a possible imbalance: the task belongs to a memcg, but the cache being allocated from is the global cache, since the child cache is not yet guaranteed to be ready. This case is also fine, since in this case the GFP_KMEMCG will not be passed and the page allocator will not attempt any cgroup accounting. Signed-off-by: Glauber Costa <glommer@parallels.com> Cc: Christoph Lameter <cl@linux.com> Cc: David Rientjes <rientjes@google.com> Cc: Frederic Weisbecker <fweisbec@redhat.com> Cc: Greg Thelen <gthelen@google.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: JoonSoo Kim <js1304@gmail.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Mel Gorman <mel@csn.ul.ie> Cc: Michal Hocko <mhocko@suse.cz> Cc: Pekka Enberg <penberg@cs.helsinki.fi> Cc: Rik van Riel <riel@redhat.com> Cc: Suleiman Souhlal <suleiman@google.com> Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'init')
1 files changed, 0 insertions, 1 deletions
diff --git a/init/Kconfig b/init/Kconfig
index 19ccb33c99d..7d30240e5bf 100644
--- a/init/Kconfig
+++ b/init/Kconfig
@@ -883,7 +883,6 @@ config MEMCG_KMEM
bool "Memory Resource Controller Kernel Memory accounting (EXPERIMENTAL)"
depends on SLUB || SLAB
- default n
The Kernel Memory extension for Memory Resource Controller can limit
the amount of memory used by kernel objects in the system. Those are