From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tejun Heo Subject: Re: [PATCH v5 04/14] kmem accounting basic infrastructure Date: Thu, 18 Oct 2012 12:47:27 -0700 Message-ID: <20121018194727.GB13370@google.com> References: <1350382611-20579-1-git-send-email-glommer@parallels.com> <1350382611-20579-5-git-send-email-glommer@parallels.com> <508035E3.4080508@parallels.com> 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=8juk3OCF47JbBIRsXz9uZ/s3yc/N/sp4lLm0Mnk7NH0=; b=wDfKrAU8nLoG5/8CYV8MafKWcvNS/aS9Xxa3Chjlnc4WppI8PKvkdkhqq3SqqIM5Xd 4wFf7PSwSfBS/wuK/4yql6PRZU6N0QHDcOLzyyWGfb07wwum+c2nqkifNNF8LR4Hc1d9 2t2qs0uHiERAWEWG0VYU60jwHD5R6teefjAyaXr6nH8DGJgw5xC6sWY/hw0BaZIa/ny5 q5xFTXuzhOyeE5v6PNQRpIsch6OyYtnR0oJoLAYp88+9e6KW7uKoaz9k5q4ptcc7R80C eSuU7dT2MVqPimWMWJLv+XkLI0TAxbjn4jOGIQnqifLSZhVI+3ePgpWHnYVB7oTtoCSG shqQ== Content-Disposition: inline In-Reply-To: <508035E3.4080508@parallels.com> Sender: owner-linux-mm@kvack.org List-ID: Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: Glauber Costa Cc: David Rientjes , linux-mm@kvack.org, cgroups@vger.kernel.org, Mel Gorman , Andrew Morton , Michal Hocko , Johannes Weiner , kamezawa.hiroyu@jp.fujitsu.com, Christoph Lameter , Pekka Enberg , devel@openvz.org, linux-kernel@vger.kernel.org, Li Zefan Hey, Glauber. On Thu, Oct 18, 2012 at 09:01:23PM +0400, Glauber Costa wrote: > That is the offensive part. But it is also how things are done in memcg > right now, and there is nothing fundamentally different in this one. > Whatever lands in the remaining offenders, can land in here. I think the problem here is that we don't have "you're committing to creation of a new cgroup" callback and thus subsystem can't synchronize locally against cgroup creation. For task migration ->attach() does that but cgroup creation may fail after ->create() succeeded so that doesn't work. We'll probably need to add ->post_create() which is invoked after creation is complete. Li? 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 From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754047Ab2JRTre (ORCPT ); Thu, 18 Oct 2012 15:47:34 -0400 Received: from mail-da0-f46.google.com ([209.85.210.46]:57692 "EHLO mail-da0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753932Ab2JRTrc (ORCPT ); Thu, 18 Oct 2012 15:47:32 -0400 Date: Thu, 18 Oct 2012 12:47:27 -0700 From: Tejun Heo To: Glauber Costa Cc: David Rientjes , linux-mm@kvack.org, cgroups@vger.kernel.org, Mel Gorman , Andrew Morton , Michal Hocko , Johannes Weiner , kamezawa.hiroyu@jp.fujitsu.com, Christoph Lameter , Pekka Enberg , devel@openvz.org, linux-kernel@vger.kernel.org, Li Zefan Subject: Re: [PATCH v5 04/14] kmem accounting basic infrastructure Message-ID: <20121018194727.GB13370@google.com> References: <1350382611-20579-1-git-send-email-glommer@parallels.com> <1350382611-20579-5-git-send-email-glommer@parallels.com> <508035E3.4080508@parallels.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <508035E3.4080508@parallels.com> User-Agent: Mutt/1.5.20 (2009-06-14) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hey, Glauber. On Thu, Oct 18, 2012 at 09:01:23PM +0400, Glauber Costa wrote: > That is the offensive part. But it is also how things are done in memcg > right now, and there is nothing fundamentally different in this one. > Whatever lands in the remaining offenders, can land in here. I think the problem here is that we don't have "you're committing to creation of a new cgroup" callback and thus subsystem can't synchronize locally against cgroup creation. For task migration ->attach() does that but cgroup creation may fail after ->create() succeeded so that doesn't work. We'll probably need to add ->post_create() which is invoked after creation is complete. Li? Thanks. -- tejun