From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752857AbZBCD2H (ORCPT ); Mon, 2 Feb 2009 22:28:07 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751384AbZBCD1z (ORCPT ); Mon, 2 Feb 2009 22:27:55 -0500 Received: from cn.fujitsu.com ([222.73.24.84]:64366 "EHLO song.cn.fujitsu.com" rhost-flags-OK-FAIL-OK-OK) by vger.kernel.org with ESMTP id S1751247AbZBCD1z (ORCPT ); Mon, 2 Feb 2009 22:27:55 -0500 Message-ID: <4987B925.1010405@cn.fujitsu.com> Date: Tue, 03 Feb 2009 11:25:25 +0800 From: Miao Xie Reply-To: miaox@cn.fujitsu.com User-Agent: Thunderbird 2.0.0.6 (Windows/20070728) MIME-Version: 1.0 To: Andrew Morton CC: mingo@elte.hu, menage@google.com, linux-kernel@vger.kernel.org, Christoph Lameter , Nick Piggin Subject: Re: [PATCH] cpuset: fix allocating page cache/slab object on the unallowed node when memory spread is set References: <4976D77C.3020107@cn.fujitsu.com> <20090127144233.18cf9b3f.akpm@linux-foundation.org> In-Reply-To: <20090127144233.18cf9b3f.akpm@linux-foundation.org> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org on 2009-1-28 6:42 Andrew Morton wrote: > On Wed, 21 Jan 2009 16:06:20 +0800 > Miao Xie wrote: > >> The task still allocated the page caches on old node after modifying its >> cpuset's mems when 'memory_spread_page' was set, it is caused by the old >> mem_allowed_list of the task, the current kernel doesn't updates it unless some >> function invokes cpuset_update_task_memory_state(), it is too late sometimes. >> We must update the mem_allowed_list of the tasks in time. >> >> Slab has the same problem. >> >> We fixes the bug by updating tasks' mem_allowed_list and spread flag after >> its cpuset's mems or spread flag is changed. >> >> >> ... >> >> --- a/kernel/kthread.c >> +++ b/kernel/kthread.c >> @@ -242,6 +242,7 @@ int kthreadd(void *unused) >> set_user_nice(tsk, KTHREAD_NICE_LEVEL); >> set_cpus_allowed_ptr(tsk, CPU_MASK_ALL_PTR); >> >> + current->mems_allowed = node_possible_map; >> current->flags |= PF_NOFREEZE | PF_FREEZER_NOSIG; > > Why this change? kthreadd() is called from rest_init(), before anyone > has had a chance to alter ->mems_allowed? I found that after mems_allowed of kthreadd was not initialized applying this patch, every bit of it is 1, so... Maybe it is redundant. Thanks! Miao > > I queued the patch pending your response to Paul's questions, thanks. > > >