From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pa0-f46.google.com (mail-pa0-f46.google.com [209.85.220.46]) by kanga.kvack.org (Postfix) with ESMTP id 530746B0253 for ; Mon, 3 Aug 2015 21:15:09 -0400 (EDT) Received: by pacgq8 with SMTP id gq8so37106724pac.3 for ; Mon, 03 Aug 2015 18:15:09 -0700 (PDT) Received: from szxga03-in.huawei.com (szxga03-in.huawei.com. [119.145.14.66]) by mx.google.com with ESMTPS id o6si29443590pds.214.2015.08.03.18.15.06 for (version=TLSv1 cipher=RC4-SHA bits=128/128); Mon, 03 Aug 2015 18:15:07 -0700 (PDT) Message-ID: <55C011A6.1090003@huawei.com> Date: Tue, 4 Aug 2015 09:13:10 +0800 From: Xishi Qiu MIME-Version: 1.0 Subject: Re: [PATCH] mm: add the block to the tail of the list in expand() References: <55BB4027.7080200@huawei.com> <55BC0392.2070205@intel.com> <55BECC85.7050206@huawei.com> <55BEE99E.8090901@intel.com> In-Reply-To: <55BEE99E.8090901@intel.com> Content-Type: text/plain; charset="windows-1252" Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: Dave Hansen Cc: Andrew Morton , Mel Gorman , Vlastimil Babka , Johannes Weiner , Michal Hocko , iamjoonsoo.kim@lge.com, alexander.h.duyck@redhat.com, sasha.levin@oracle.com, Linux MM , LKML On 2015/8/3 12:10, Dave Hansen wrote: > On 08/02/2015 07:05 PM, Xishi Qiu wrote: >>>> Also, this might not do very much good in practice. If you are >>>> splitting a high-order page, you are doing the split because the >>>> lower-order lists are empty. So won't that list_add() be to an empty >> >> I made a mistake, you are right, all the lower-order lists are empty, >> so it is no sense to add to the tail. > > I actually tested this experimentally and the lists are not always > empty. It's probably __rmqueue_smallest() vs. __rmqueue_fallback() logic. > > In any case, you might want to double-check. > Hi Dave, How did you do the experiment? Thanks, Xishi Qiu > . > -- 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 From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754699AbbHDBNr (ORCPT ); Mon, 3 Aug 2015 21:13:47 -0400 Received: from szxga03-in.huawei.com ([119.145.14.66]:11611 "EHLO szxga03-in.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751136AbbHDBNq (ORCPT ); Mon, 3 Aug 2015 21:13:46 -0400 Message-ID: <55C011A6.1090003@huawei.com> Date: Tue, 4 Aug 2015 09:13:10 +0800 From: Xishi Qiu User-Agent: Mozilla/5.0 (Windows NT 6.1; rv:12.0) Gecko/20120428 Thunderbird/12.0.1 MIME-Version: 1.0 To: Dave Hansen CC: Andrew Morton , Mel Gorman , Vlastimil Babka , Johannes Weiner , Michal Hocko , , , , Linux MM , LKML Subject: Re: [PATCH] mm: add the block to the tail of the list in expand() References: <55BB4027.7080200@huawei.com> <55BC0392.2070205@intel.com> <55BECC85.7050206@huawei.com> <55BEE99E.8090901@intel.com> In-Reply-To: <55BEE99E.8090901@intel.com> Content-Type: text/plain; charset="windows-1252" Content-Transfer-Encoding: 7bit X-Originating-IP: [10.177.25.179] X-CFilter-Loop: Reflected X-Mirapoint-Virus-RAPID-Raw: score=unknown(0), refid=str=0001.0A020203.55C011B0.0136,ss=1,re=0.000,recu=0.000,reip=0.000,cl=1,cld=1,fgs=0, ip=0.0.0.0, so=2013-05-26 15:14:31, dmn=2013-03-21 17:37:32 X-Mirapoint-Loop-Id: b928677f28a6030073980125ab855d45 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2015/8/3 12:10, Dave Hansen wrote: > On 08/02/2015 07:05 PM, Xishi Qiu wrote: >>>> Also, this might not do very much good in practice. If you are >>>> splitting a high-order page, you are doing the split because the >>>> lower-order lists are empty. So won't that list_add() be to an empty >> >> I made a mistake, you are right, all the lower-order lists are empty, >> so it is no sense to add to the tail. > > I actually tested this experimentally and the lists are not always > empty. It's probably __rmqueue_smallest() vs. __rmqueue_fallback() logic. > > In any case, you might want to double-check. > Hi Dave, How did you do the experiment? Thanks, Xishi Qiu > . >