Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1761661Ab3DCPbg (ORCPT ); Wed, 3 Apr 2013 11:31:36 -0400 Received: from cantor2.suse.de ([195.135.220.15]:49900 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1761293Ab3DCPbe (ORCPT ); Wed, 3 Apr 2013 11:31:34 -0400 Date: Wed, 3 Apr 2013 17:31:33 +0200 From: Michal Hocko To: Li Zefan Cc: linux-mm@kvack.org, LKML , Cgroups , Tejun Heo , Glauber Costa , KAMEZAWA Hiroyuki , Johannes Weiner Subject: Re: [RFC][PATCH 2/7] memcg: don't use mem_cgroup_get() when creating a kmemcg cache Message-ID: <20130403153133.GM16471@dhcp22.suse.cz> References: <515BF233.6070308@huawei.com> <515BF275.5080408@huawei.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <515BF275.5080408@huawei.com> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1897 Lines: 62 On Wed 03-04-13 17:12:21, Li Zefan wrote: > Use css_get()/css_put() instead of mem_cgroup_get()/mem_cgroup_put(). > > Signed-off-by: Li Zefan > --- > mm/memcontrol.c | 10 +++++----- > 1 file changed, 5 insertions(+), 5 deletions(-) > > diff --git a/mm/memcontrol.c b/mm/memcontrol.c > index 43ca91d..dafacb8 100644 > --- a/mm/memcontrol.c > +++ b/mm/memcontrol.c > @@ -3191,7 +3191,7 @@ void memcg_release_cache(struct kmem_cache *s) > list_del(&s->memcg_params->list); > mutex_unlock(&memcg->slab_caches_mutex); > > - mem_cgroup_put(memcg); > + css_put(&memcg->css); > out: > kfree(s->memcg_params); > } > @@ -3350,16 +3350,18 @@ static struct kmem_cache *memcg_create_kmem_cache(struct mem_cgroup *memcg, > > mutex_lock(&memcg_cache_mutex); > new_cachep = cachep->memcg_params->memcg_caches[idx]; > - if (new_cachep) > + if (new_cachep) { > + css_put(&memcg->css); > goto out; > + } > > new_cachep = kmem_cache_dup(memcg, cachep); > if (new_cachep == NULL) { > new_cachep = cachep; > + css_put(&memcg->css); > goto out; > } > > - mem_cgroup_get(memcg); > atomic_set(&new_cachep->memcg_params->nr_pages , 0); > > cachep->memcg_params->memcg_caches[idx] = new_cachep; > @@ -3449,8 +3451,6 @@ static void memcg_create_cache_work_func(struct work_struct *w) > > cw = container_of(w, struct create_work, work); > memcg_create_kmem_cache(cw->memcg, cw->cachep); > - /* Drop the reference gotten when we enqueued. */ > - css_put(&cw->memcg->css); > kfree(cw); > } You are putting references but I do not see any single css_{try}get here. /me puzzled. -- Michal Hocko SUSE Labs -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/