From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751067Ab3A1CH5 (ORCPT ); Sun, 27 Jan 2013 21:07:57 -0500 Received: from cn.fujitsu.com ([222.73.24.84]:49286 "EHLO song.cn.fujitsu.com" rhost-flags-OK-FAIL-OK-OK) by vger.kernel.org with ESMTP id S1750710Ab3A1CH4 (ORCPT ); Sun, 27 Jan 2013 21:07:56 -0500 X-IronPort-AV: E=Sophos;i="4.84,549,1355068800"; d="scan'208";a="6651371" Message-ID: <5105DD4B.9020901@cn.fujitsu.com> Date: Mon, 28 Jan 2013 10:07:07 +0800 From: Tang Chen User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:12.0) Gecko/20120430 Thunderbird/12.0.1 MIME-Version: 1.0 To: "H. Peter Anvin" CC: Andrew Morton , jiang.liu@huawei.com, wujianguo@huawei.com, wency@cn.fujitsu.com, laijs@cn.fujitsu.com, linfeng@cn.fujitsu.com, yinghai@kernel.org, isimatu.yasuaki@jp.fujitsu.com, rob@landley.net, kosaki.motohiro@jp.fujitsu.com, minchan.kim@gmail.com, mgorman@suse.de, rientjes@google.com, guz.fnst@cn.fujitsu.com, rusty@rustcorp.com.au, lliubbo@gmail.com, jaegeuk.hanse@gmail.com, tony.luck@intel.com, glommer@parallels.com, linux-kernel@vger.kernel.org, linux-mm@kvack.org Subject: Re: [PATCH 3/3] acpi, memory-hotplug: Support getting hotplug info from SRAT. References: <1359106929-3034-1-git-send-email-tangchen@cn.fujitsu.com> <1359106929-3034-4-git-send-email-tangchen@cn.fujitsu.com> <20130125171230.34c5a273.akpm@linux-foundation.org> <51033186.3000706@zytor.com> In-Reply-To: <51033186.3000706@zytor.com> X-MIMETrack: Itemize by SMTP Server on mailserver/fnst(Release 8.5.3|September 15, 2011) at 2013/01/28 10:06:50, Serialize by Router on mailserver/fnst(Release 8.5.3|September 15, 2011) at 2013/01/28 10:06:51, Serialize complete at 2013/01/28 10:06:51 Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset=ISO-8859-1; format=flowed Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 01/26/2013 09:29 AM, H. Peter Anvin wrote: > On 01/25/2013 05:12 PM, Andrew Morton wrote: >> On Fri, 25 Jan 2013 17:42:09 +0800 >> Tang Chen wrote: >> >>> NOTE: Using this way will cause NUMA performance down because the whole node >>> will be set as ZONE_MOVABLE, and kernel cannot use memory on it. >>> If users don't want to lose NUMA performance, just don't use it. >> >> I agree with this, but it means that nobody will test any of your new code. >> >> To get improved testing coverage, can you think of any temporary >> testing-only patch which will cause testers to exercise the >> memory-hotplug changes? >> > > There is another problem: if ALL the nodes in the system support > hotpluggable memory, what happens? > Hi HPA, I think I missed this case. If all the memory is hotpluggable, and user specified movablemem_map=acpi, all the memory could be set as movable, and the kernel will fail to start. I will post a patch to fix it. How about always keep node0 unhotpluggable ? Thanks. :)