From 426589f571f7d6d5ab2ca33ece73164149279ca1 Mon Sep 17 00:00:00 2001 From: Vladimir Davydov Date: Thu, 12 Feb 2015 14:59:23 -0800 Subject: slab: link memcg caches of the same kind into a list Sometimes, we need to iterate over all memcg copies of a particular root kmem cache. Currently, we use memcg_cache_params->memcg_caches array for that, because it contains all existing memcg caches. However, it's a bad practice to keep all caches, including those that belong to offline cgroups, in this array, because it will be growing beyond any bounds then. I'm going to wipe away dead caches from it to save space. To still be able to perform iterations over all memcg caches of the same kind, let us link them into a list. Signed-off-by: Vladimir Davydov Cc: Johannes Weiner Cc: Michal Hocko Cc: Tejun Heo Cc: Christoph Lameter Cc: Pekka Enberg Cc: David Rientjes Cc: Joonsoo Kim Cc: Dave Chinner Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/slab.c | 13 +++++-------- 1 file changed, 5 insertions(+), 8 deletions(-) (limited to 'mm/slab.c') diff --git a/mm/slab.c b/mm/slab.c index 65b5dcb6f671..7894017bc160 100644 --- a/mm/slab.c +++ b/mm/slab.c @@ -3708,8 +3708,7 @@ static int do_tune_cpucache(struct kmem_cache *cachep, int limit, int batchcount, int shared, gfp_t gfp) { int ret; - struct kmem_cache *c = NULL; - int i = 0; + struct kmem_cache *c; ret = __do_tune_cpucache(cachep, limit, batchcount, shared, gfp); @@ -3719,12 +3718,10 @@ static int do_tune_cpucache(struct kmem_cache *cachep, int limit, if ((ret < 0) || !is_root_cache(cachep)) return ret; - VM_BUG_ON(!mutex_is_locked(&slab_mutex)); - for_each_memcg_cache_index(i) { - c = cache_from_memcg_idx(cachep, i); - if (c) - /* return value determined by the parent cache only */ - __do_tune_cpucache(c, limit, batchcount, shared, gfp); + lockdep_assert_held(&slab_mutex); + for_each_memcg_cache(c, cachep) { + /* return value determined by the root cache only */ + __do_tune_cpucache(c, limit, batchcount, shared, gfp); } return ret; -- cgit v1.2.3-55-g7522