From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754715AbaFLUir (ORCPT ); Thu, 12 Jun 2014 16:38:47 -0400 Received: from mx2.parallels.com ([199.115.105.18]:51285 "EHLO mx2.parallels.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752089AbaFLUik (ORCPT ); Thu, 12 Jun 2014 16:38:40 -0400 From: Vladimir Davydov To: CC: , , , , , , , Subject: [PATCH -mm v3 3/8] memcg: mark caches that belong to offline memcgs as dead Date: Fri, 13 Jun 2014 00:38:17 +0400 Message-ID: <8f3b741b0d62204c34c6935fe6b00f73c3e1fc49.1402602126.git.vdavydov@parallels.com> X-Mailer: git-send-email 1.7.10.4 In-Reply-To: References: MIME-Version: 1.0 Content-Type: text/plain X-Originating-IP: [81.5.110.170] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org This will be used by the next patches. Signed-off-by: Vladimir Davydov --- include/linux/slab.h | 2 ++ mm/memcontrol.c | 3 +++ mm/slab.h | 25 +++++++++++++++++++++++++ 3 files changed, 30 insertions(+) diff --git a/include/linux/slab.h b/include/linux/slab.h index d9716fdc8211..d99d5212b815 100644 --- a/include/linux/slab.h +++ b/include/linux/slab.h @@ -527,6 +527,7 @@ static __always_inline void *kmalloc_node(size_t size, gfp_t flags, int node) * @list: list_head for the list of all caches in this memcg * @root_cache: pointer to the global, root cache, this cache was derived from * @refcnt: reference counter + * @dead: set to true when owner memcg is turned offline * @unregister_work: worker to destroy the cache */ struct memcg_cache_params { @@ -541,6 +542,7 @@ struct memcg_cache_params { struct list_head list; struct kmem_cache *root_cache; atomic_long_t refcnt; + bool dead; struct work_struct unregister_work; }; }; diff --git a/mm/memcontrol.c b/mm/memcontrol.c index 886b5b414958..8f08044d26a7 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -3294,7 +3294,10 @@ static void memcg_unregister_all_caches(struct mem_cgroup *memcg) mutex_lock(&memcg_slab_mutex); list_for_each_entry_safe(params, tmp, &memcg->memcg_slab_caches, list) { cachep = memcg_params_to_cache(params); + + memcg_cache_mark_dead(cachep); kmem_cache_shrink(cachep); + if (atomic_long_dec_and_test(&cachep->memcg_params->refcnt)) memcg_unregister_cache(cachep); } diff --git a/mm/slab.h b/mm/slab.h index 961a3fb1f5a2..2af5a0bc00a4 100644 --- a/mm/slab.h +++ b/mm/slab.h @@ -121,6 +121,26 @@ static inline bool is_root_cache(struct kmem_cache *s) return !s->memcg_params || s->memcg_params->is_root_cache; } +static inline bool memcg_cache_dead(struct kmem_cache *s) +{ + if (is_root_cache(s)) + return false; + + /* + * Since this function can be called without holding any locks, it + * needs a barrier here to guarantee the read won't be reordered. + */ + smp_rmb(); + return s->memcg_params->dead; +} + +static inline void memcg_cache_mark_dead(struct kmem_cache *s) +{ + BUG_ON(is_root_cache(s)); + s->memcg_params->dead = true; + smp_wmb(); /* matches rmb in memcg_cache_dead() */ +} + static inline bool slab_equal_or_root(struct kmem_cache *s, struct kmem_cache *p) { @@ -203,6 +223,11 @@ static inline bool is_root_cache(struct kmem_cache *s) return true; } +static inline bool memcg_cache_dead(struct kmem_cache *s) +{ + return false; +} + static inline bool slab_equal_or_root(struct kmem_cache *s, struct kmem_cache *p) { -- 1.7.10.4