Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755363AbYLKAWy (ORCPT ); Wed, 10 Dec 2008 19:22:54 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752009AbYLKAWq (ORCPT ); Wed, 10 Dec 2008 19:22:46 -0500 Received: from fgwmail5.fujitsu.co.jp ([192.51.44.35]:46614 "EHLO fgwmail5.fujitsu.co.jp" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751820AbYLKAWp (ORCPT ); Wed, 10 Dec 2008 19:22:45 -0500 Date: Thu, 11 Dec 2008 09:21:50 +0900 From: KAMEZAWA Hiroyuki To: Paul Menage Cc: "linux-mm@kvack.org" , "balbir@linux.vnet.ibm.com" , "nishimura@mxp.nes.nec.co.jp" , "lizf@cn.fujitsu.com" , "kosaki.motohiro@jp.fujitsu.com" , "linux-kernel@vger.kernel.org" Subject: Re: [RFC][PATCH 1/6] memcg: fix pre_destory handler Message-Id: <20081211092150.b62f8c20.kamezawa.hiroyu@jp.fujitsu.com> In-Reply-To: <6599ad830812101100v4dc7f124jded0d767b92e541a@mail.gmail.com> References: <20081209200213.0e2128c1.kamezawa.hiroyu@jp.fujitsu.com> <20081209200647.a1fa76a9.kamezawa.hiroyu@jp.fujitsu.com> <6599ad830812100240g5e549a5cqe29cbea736788865@mail.gmail.com> <29741.10.75.179.61.1228908581.squirrel@webmail-b.css.fujitsu.com> <6599ad830812101035v33dbc6cfh57aa5510f6d65d54@mail.gmail.com> <6599ad830812101100v4dc7f124jded0d767b92e541a@mail.gmail.com> Organization: FUJITSU Co. LTD. X-Mailer: Sylpheed 2.5.0 (GTK+ 2.10.14; i686-pc-mingw32) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1859 Lines: 51 On Wed, 10 Dec 2008 11:00:35 -0800 Paul Menage wrote: > On Wed, Dec 10, 2008 at 10:35 AM, Paul Menage wrote: > > On Wed, Dec 10, 2008 at 3:29 AM, KAMEZAWA Hiroyuki > > wrote: > >> > >> (BTW, I don't like hierarchy-walk-by-small-locks approarch now because > >> I'd like to implement scan-and-stop-continue routine. > >> See how readdir() aginst /proc scans PID. It's very roboust against > >> very temporal PIDs.) > > > > So you mean that you want to be able to sleep, and then contine > > approximately where you left off, without keeping any kind of > > reference count on the last cgroup that you touched? OK, so in that > > case I agree that you would need some kind of hierarch > > Oops, didn't finish that sentence. > > I agree that you'd need some kind of hierarchical-restart. But I'd > like to play with / look at your cgroup-id patch more closely and see > if we can come up with something simpler that still does what you > want. > Sure, I have to do, too. It's still too young. > One particular problem with the patch as it stands is that the ids > should be per-css, not per-cgroup, since a css can move between > hierarchies and hence between cgroups. (Currently only at bind/unbind > time, but it still results in a cgroup change). > If per-css, looking up function will be == struct cgroup_subsys_state *cgroup_css_lookup(subsys_id, id) == Do you mean this ? ok, I'll implement and see what happens. Maybe I'll move hooks to prepare/destroy IDs to subsys layer and assign ID only when subsys want IDs. -Kame -- 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/