From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753432AbdKIKzv (ORCPT ); Thu, 9 Nov 2017 05:55:51 -0500 Received: from szxga04-in.huawei.com ([45.249.212.190]:10423 "EHLO szxga04-in.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752730AbdKIKzt (ORCPT ); Thu, 9 Nov 2017 05:55:49 -0500 Subject: Re: [PATCH RFC v2 4/4] mm/mempolicy: add nodes_empty check in SYSC_migrate_pages To: Christopher Lameter References: <1509099265-30868-1-git-send-email-xieyisheng1@huawei.com> <1509099265-30868-5-git-send-email-xieyisheng1@huawei.com> <04e4cb50-8cba-58af-1a5e-61e818cffa70@suse.cz> <4b08f1e9-5449-6ea2-e7da-65fe5f678683@huawei.com> CC: Vlastimil Babka , , , , , , , , , , , Andi Kleen From: Yisheng Xie Message-ID: <9991dd10-8883-7c82-bb4e-8145ea2b7299@huawei.com> Date: Thu, 9 Nov 2017 18:54:57 +0800 User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:45.0) Gecko/20100101 Thunderbird/45.1.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset="windows-1252" Content-Transfer-Encoding: 7bit X-Originating-IP: [10.177.29.40] X-CFilter-Loop: Reflected X-Mirapoint-Virus-RAPID-Raw: score=unknown(0), refid=str=0001.0A020201.5A043417.00B0,ss=1,re=0.000,recu=0.000,reip=0.000,cl=1,cld=1,fgs=0, ip=0.0.0.0, so=2014-11-16 11:51:01, dmn=2013-03-21 17:37:32 X-Mirapoint-Loop-Id: 7833650ca11dd661885654e761560980 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Christopher, On 2017/11/8 23:02, Christopher Lameter wrote: > On Wed, 8 Nov 2017, Yisheng Xie wrote: > >> Another case is current process is *not* the same as target process, and >> when current process try to migrate pages of target process from old_nodes >> to new_nodes, the new_nodes should be a subset of target process cpuset. > > The caller of migrate_pages should be able to migrate the target process > pages anywhere the caller can allocate memory. If that is outside the > target processes cpuset then that is fine. Pagecache pages that are not > allocated by the target process already are not subject to the target > processes restriction. So this is not that unusual. So there is no need to check the restriction of target process cpuset, right? I hope that I do not miss anything :) Thanks Yisheng Xie > > . > From mboxrd@z Thu Jan 1 00:00:00 1970 From: Yisheng Xie Subject: Re: [PATCH RFC v2 4/4] mm/mempolicy: add nodes_empty check in SYSC_migrate_pages Date: Thu, 9 Nov 2017 18:54:57 +0800 Message-ID: <9991dd10-8883-7c82-bb4e-8145ea2b7299@huawei.com> References: <1509099265-30868-1-git-send-email-xieyisheng1@huawei.com> <1509099265-30868-5-git-send-email-xieyisheng1@huawei.com> <04e4cb50-8cba-58af-1a5e-61e818cffa70@suse.cz> <4b08f1e9-5449-6ea2-e7da-65fe5f678683@huawei.com> Mime-Version: 1.0 Content-Type: text/plain; charset="windows-1252" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: Sender: linux-kernel-owner@vger.kernel.org To: Christopher Lameter Cc: Vlastimil Babka , akpm@linux-foundation.org, mhocko@suse.com, mingo@kernel.org, rientjes@google.com, n-horiguchi@ah.jp.nec.com, salls@cs.ucsb.edu, linux-mm@kvack.org, linux-kernel@vger.kernel.org, tanxiaojun@huawei.com, linux-api@vger.kernel.org, Andi Kleen List-Id: linux-api@vger.kernel.org Hi Christopher, On 2017/11/8 23:02, Christopher Lameter wrote: > On Wed, 8 Nov 2017, Yisheng Xie wrote: > >> Another case is current process is *not* the same as target process, and >> when current process try to migrate pages of target process from old_nodes >> to new_nodes, the new_nodes should be a subset of target process cpuset. > > The caller of migrate_pages should be able to migrate the target process > pages anywhere the caller can allocate memory. If that is outside the > target processes cpuset then that is fine. Pagecache pages that are not > allocated by the target process already are not subject to the target > processes restriction. So this is not that unusual. So there is no need to check the restriction of target process cpuset, right? I hope that I do not miss anything :) Thanks Yisheng Xie > > . > From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-it0-f72.google.com (mail-it0-f72.google.com [209.85.214.72]) by kanga.kvack.org (Postfix) with ESMTP id 7B04D440CD7 for ; Thu, 9 Nov 2017 05:59:16 -0500 (EST) Received: by mail-it0-f72.google.com with SMTP id r127so9006839itb.4 for ; Thu, 09 Nov 2017 02:59:16 -0800 (PST) Received: from szxga04-in.huawei.com (szxga04-in.huawei.com. [45.249.212.190]) by mx.google.com with ESMTPS id y14si6216448pfe.180.2017.11.09.02.59.11 for (version=TLS1 cipher=AES128-SHA bits=128/128); Thu, 09 Nov 2017 02:59:11 -0800 (PST) Subject: Re: [PATCH RFC v2 4/4] mm/mempolicy: add nodes_empty check in SYSC_migrate_pages References: <1509099265-30868-1-git-send-email-xieyisheng1@huawei.com> <1509099265-30868-5-git-send-email-xieyisheng1@huawei.com> <04e4cb50-8cba-58af-1a5e-61e818cffa70@suse.cz> <4b08f1e9-5449-6ea2-e7da-65fe5f678683@huawei.com> From: Yisheng Xie Message-ID: <9991dd10-8883-7c82-bb4e-8145ea2b7299@huawei.com> Date: Thu, 9 Nov 2017 18:54:57 +0800 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset="windows-1252" Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: Christopher Lameter Cc: Vlastimil Babka , akpm@linux-foundation.org, mhocko@suse.com, mingo@kernel.org, rientjes@google.com, n-horiguchi@ah.jp.nec.com, salls@cs.ucsb.edu, linux-mm@kvack.org, linux-kernel@vger.kernel.org, tanxiaojun@huawei.com, linux-api@vger.kernel.org, Andi Kleen Hi Christopher, On 2017/11/8 23:02, Christopher Lameter wrote: > On Wed, 8 Nov 2017, Yisheng Xie wrote: > >> Another case is current process is *not* the same as target process, and >> when current process try to migrate pages of target process from old_nodes >> to new_nodes, the new_nodes should be a subset of target process cpuset. > > The caller of migrate_pages should be able to migrate the target process > pages anywhere the caller can allocate memory. If that is outside the > target processes cpuset then that is fine. Pagecache pages that are not > allocated by the target process already are not subject to the target > processes restriction. So this is not that unusual. So there is no need to check the restriction of target process cpuset, right? I hope that I do not miss anything :) Thanks Yisheng Xie > > . > -- 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