From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail190.messagelabs.com (mail190.messagelabs.com [216.82.249.51]) by kanga.kvack.org (Postfix) with ESMTP id 8FB2C8D0039 for ; Fri, 4 Mar 2011 03:34:39 -0500 (EST) Received: from m1.gw.fujitsu.co.jp (unknown [10.0.50.71]) by fgwmail5.fujitsu.co.jp (Postfix) with ESMTP id A00FC3EE0BD for ; Fri, 4 Mar 2011 17:34:36 +0900 (JST) Received: from smail (m1 [127.0.0.1]) by outgoing.m1.gw.fujitsu.co.jp (Postfix) with ESMTP id 85EC845DE5A for ; Fri, 4 Mar 2011 17:34:36 +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 6B69B45DE53 for ; Fri, 4 Mar 2011 17:34:36 +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 5D9A9E38006 for ; Fri, 4 Mar 2011 17:34:36 +0900 (JST) Received: from m108.s.css.fujitsu.com (m108.s.css.fujitsu.com [10.249.87.108]) by s1.gw.fujitsu.co.jp (Postfix) with ESMTP id 20011E08001 for ; Fri, 4 Mar 2011 17:34:36 +0900 (JST) Date: Fri, 4 Mar 2011 17:28:15 +0900 From: KAMEZAWA Hiroyuki Subject: Re: [Bugme-new] [Bug 30432] New: rmdir on cgroup can cause hang tasks Message-Id: <20110304172815.9d9e3672.kamezawa.hiroyu@jp.fujitsu.com> In-Reply-To: <20110304000355.4f68bab1.akpm@linux-foundation.org> References: <20110304000355.4f68bab1.akpm@linux-foundation.org> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: Andrew Morton Cc: containers@lists.osdl.org, bugzilla-daemon@bugzilla.kernel.org, bugme-daemon@bugzilla.kernel.org, linux-mm@kvack.org, Paul Menage , Daniel Poelzleithner On Fri, 4 Mar 2011 00:03:55 -0800 Andrew Morton wrote: > > [ 5066.149853] Call Trace: > > [ 5066.149853] [] schedule_timeout+0x215/0x2f0 > > [ 5066.149853] [] ? task_rq_lock+0x5d/0xa0 > > [ 5066.149853] [] ? try_to_wake_up+0xc3/0x410 > > [ 5066.149853] [] wait_for_common+0xdb/0x180 > > [ 5066.149853] [] ? default_wake_function+0x0/0x20 > > [ 5066.244366] [] wait_for_completion+0x1d/0x20 > > [ 5066.244366] [] synchronize_sched+0x55/0x60 > > [ 5066.244366] [] ? wakeme_after_rcu+0x0/0x20 > > [ 5066.244366] [] mem_cgroup_start_move+0x93/0xa0 > > [ 5066.244366] [] mem_cgroup_force_empty+0xdb/0x640 > > [ 5066.244366] [] mem_cgroup_pre_destroy+0x14/0x20 > > [ 5066.244366] [] cgroup_rmdir+0xc1/0x560 > > [ 5066.244366] [] ? autoremove_wake_function+0x0/0x40 > > [ 5066.244366] [] vfs_rmdir+0xb4/0x110 > > [ 5066.244366] [] do_rmdir+0x133/0x140 > > [ 5066.244366] [] ? call_rcu_sched+0x15/0x20 > > [ 5066.244366] [] ? audit_syscall_entry+0x1df/0x280 > > [ 5066.244366] [] sys_rmdir+0x16/0x20 > > [ 5066.244366] [] system_call_fastpath+0x16/0x1b > This seems.... == static void mem_cgroup_start_move(struct mem_cgroup *mem) { ..... put_online_cpus(); synchronize_rcu(); <---------(*) } == Waiting on above synchronize_rcu(). Hmm... -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