From mboxrd@z Thu Jan 1 00:00:00 1970 From: Glauber Costa Subject: Re: [PATCH v3 16/28] memcg: kmem controller charge/uncharge infrastructure Date: Wed, 30 May 2012 17:37:57 +0400 Message-ID: <4FC622B5.9080600@parallels.com> References: <1337951028-3427-1-git-send-email-glommer@parallels.com> <1337951028-3427-17-git-send-email-glommer@parallels.com> <20120530130416.GD25094@somewhere.redhat.com> <4FC61B4E.2060206@parallels.com> <20120530133736.GF25094@somewhere.redhat.com> Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20120530133736.GF25094@somewhere.redhat.com> Sender: owner-linux-mm@kvack.org List-ID: Content-Type: text/plain; charset="us-ascii"; format="flowed" To: Frederic Weisbecker Cc: linux-kernel@vger.kernel.org, cgroups@vger.kernel.org, linux-mm@kvack.org, kamezawa.hiroyu@jp.fujitsu.com, Tejun Heo , Li Zefan , Greg Thelen , Suleiman Souhlal , Michal Hocko , Johannes Weiner , devel@openvz.org, David Rientjes , Christoph Lameter , Pekka Enberg On 05/30/2012 05:37 PM, Frederic Weisbecker wrote: > Right. __mem_cgroup_get_kmem_cache() fetches the memcg of the owner > and calls memcg_create_cache_enqueue() which does css_tryget(&memcg->css). > After this tryget I think you're fine. And in-between you're safe against > css_set removal due to rcu_read_lock(). > > I'm less clear with __mem_cgroup_new_kmem_page() though... That one does not get memcg->css but it does call mem_cgroup_get(), that does prevent against the memcg structure being freed, which I believe to be good enough. -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: email@kvack.org