From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx178.postini.com [74.125.245.178]) by kanga.kvack.org (Postfix) with SMTP id A95BF6B00F7 for ; Thu, 12 Apr 2012 07:19:34 -0400 (EDT) Received: from m1.gw.fujitsu.co.jp (unknown [10.0.50.71]) by fgwmail6.fujitsu.co.jp (Postfix) with ESMTP id CD8CE3EE0BB for ; Thu, 12 Apr 2012 20:19:32 +0900 (JST) Received: from smail (m1 [127.0.0.1]) by outgoing.m1.gw.fujitsu.co.jp (Postfix) with ESMTP id AD73245DE5B for ; Thu, 12 Apr 2012 20:19:32 +0900 (JST) Received: from s1.gw.fujitsu.co.jp (s1.gw.fujitsu.co.jp [10.0.50.91]) by m1.gw.fujitsu.co.jp (Postfix) with ESMTP id 8F7B645DE59 for ; Thu, 12 Apr 2012 20:19:32 +0900 (JST) Received: from s1.gw.fujitsu.co.jp (localhost.localdomain [127.0.0.1]) by s1.gw.fujitsu.co.jp (Postfix) with ESMTP id 7E83B1DB8057 for ; Thu, 12 Apr 2012 20:19:32 +0900 (JST) Received: from ml14.s.css.fujitsu.com (ml14.s.css.fujitsu.com [10.240.81.134]) by s1.gw.fujitsu.co.jp (Postfix) with ESMTP id 344361DB804B for ; Thu, 12 Apr 2012 20:19:32 +0900 (JST) Message-ID: <4F86B9BE.8000105@jp.fujitsu.com> Date: Thu, 12 Apr 2012 20:17:18 +0900 From: KAMEZAWA Hiroyuki MIME-Version: 1.0 Subject: [PATCH v1 0/7] memcg remove pre_destroy Content-Type: text/plain; charset=ISO-2022-JP Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: "linux-mm@kvack.org" Cc: "cgroups@vger.kernel.org" , Michal Hocko , Johannes Weiner , Tejun Heo , Glauber Costa , Hugh Dickins , Andrew Morton , KAMEZAWA Hiroyuki In recent discussion, Tejun Heo, cgroup maintainer, has a plan to remove ->pre_destroy(). And now, in cgroup tree, pre_destroy() failure cause WARNING. By pre_destroy(), rmdir of cgroup can return -EBUSY or some error. It makes cgroup complicated and unstable. I said O.K. to remove it and this patch is modification for memcg. One of problem in current implementation is that memcg moves all charges to parent in pre_destroy(). At doing so, if use_hierarchy=0, pre_destroy() may hit parent's limit and may return -EBUSY. To fix this problem, this patch changes behavior of rmdir() as - if use_hierarchy=0, all remaining charges will go to root cgroup. - if use_hierarchy=1, all remaining charges will go to the parent. By this, rmdir failure will not be caused by parent's limitation. And I think this meets meaning of use_hierarchy. This series does - add above change of behavior - use workqueue to move all pages to parent - remove unnecessary codes. I'm sorry if my reply is delayed, I'm not sure I can have enough time in this weekend. Any comments are welcomed. Thanks, -Kame -- 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