From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754918Ab3LPRV5 (ORCPT ); Mon, 16 Dec 2013 12:21:57 -0500 Received: from mail-qc0-f182.google.com ([209.85.216.182]:36220 "EHLO mail-qc0-f182.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754325Ab3LPRVz (ORCPT ); Mon, 16 Dec 2013 12:21:55 -0500 Date: Mon, 16 Dec 2013 12:21:43 -0500 From: Tejun Heo To: Michal Hocko Cc: Li Zefan , Hugh Dickins , Johannes Weiner , Andrew Morton , KAMEZAWA Hiroyuki , linux-mm@kvack.org, cgroups@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: 3.13-rc breaks MEMCG_SWAP Message-ID: <20131216172143.GJ32509@htj.dyndns.org> References: <52AEC989.4080509@huawei.com> <20131216095345.GB23582@dhcp22.suse.cz> <20131216104042.GC23582@dhcp22.suse.cz> <20131216163530.GH32509@htj.dyndns.org> <20131216171937.GG26797@dhcp22.suse.cz> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20131216171937.GG26797@dhcp22.suse.cz> 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 Hey, On Mon, Dec 16, 2013 at 06:19:37PM +0100, Michal Hocko wrote: > I have to think about it some more (the brain is not working anymore > today). But what we really need is that nobody gets the same id while > the css is alive. So css_from_id returning NULL doesn't seem to be > enough. Oh, I meant whether it's necessary to keep css_from_id() working (ie. doing successful lookups) between offline and release, because that's where lifetimes are coupled. IOW, if it's enough for cgroup to not recycle the ID until all css's are released && fail css_from_id() lookup after the css is offlined, I can make a five liner quick fix. Thanks. -- tejun From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tejun Heo Subject: Re: 3.13-rc breaks MEMCG_SWAP Date: Mon, 16 Dec 2013 12:21:43 -0500 Message-ID: <20131216172143.GJ32509@htj.dyndns.org> References: <52AEC989.4080509@huawei.com> <20131216095345.GB23582@dhcp22.suse.cz> <20131216104042.GC23582@dhcp22.suse.cz> <20131216163530.GH32509@htj.dyndns.org> <20131216171937.GG26797@dhcp22.suse.cz> Mime-Version: 1.0 Return-path: DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=sender:date:from:to:cc:subject:message-id:references:mime-version :content-type:content-disposition:in-reply-to:user-agent; bh=9z3pM0d8nUflHSTQVJfvltIGHX3QWpdSjzLJA0Uu8sc=; b=TK6qYlpCBDD/f8+t4996ZqAwDZxR55ZIiShyYeQ9Gwxdh0PpL/Jj6YmXen8LiGGYxd AGETytsEEht9ba+eDxld8bJeg2g4DGAgn8binwUNbJYe+/qax3WIHQWyRs3970Brih8F eYDkBS/YCBRfCyCHPCe6QVCTVyrQpfORhN4aJ7XX0/u+Oocx+Kl8DsB8bsfcbIYfmPsH JqtPwNVB+yu+SrnxUfyyGm8c8cEJ35wYZIMvtW09jGvWIS7COP/H7irz+18xYWCEvfAp 2+DJykSsFqLXOpco2N4JQ8wORsSElnpgc0plDuzF16CBmeS8bH1StKh0E8QReKUEp6xO lsGw== Content-Disposition: inline In-Reply-To: <20131216171937.GG26797@dhcp22.suse.cz> Sender: owner-linux-mm@kvack.org List-ID: Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: Michal Hocko Cc: Li Zefan , Hugh Dickins , Johannes Weiner , Andrew Morton , KAMEZAWA Hiroyuki , linux-mm@kvack.org, cgroups@vger.kernel.org, linux-kernel@vger.kernel.org Hey, On Mon, Dec 16, 2013 at 06:19:37PM +0100, Michal Hocko wrote: > I have to think about it some more (the brain is not working anymore > today). But what we really need is that nobody gets the same id while > the css is alive. So css_from_id returning NULL doesn't seem to be > enough. Oh, I meant whether it's necessary to keep css_from_id() working (ie. doing successful lookups) between offline and release, because that's where lifetimes are coupled. IOW, if it's enough for cgroup to not recycle the ID until all css's are released && fail css_from_id() lookup after the css is offlined, I can make a five liner quick fix. Thanks. -- tejun -- 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/ . Don't email: email@kvack.org