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 3CA8A6B0044 for ; Thu, 10 Oct 2013 15:20:55 -0400 (EDT) Received: by mail-pa0-f46.google.com with SMTP id fa1so3199516pad.33 for ; Thu, 10 Oct 2013 12:20:54 -0700 (PDT) Message-ID: <1381432630.26234.6.camel@misato.fc.hp.com> Subject: Re: [PATCH part1 v6 4/6] x86/mem-hotplug: Support initialize page tables in bottom-up From: Toshi Kani Date: Thu, 10 Oct 2013 13:17:10 -0600 In-Reply-To: <5256E01B.9050802@zytor.com> References: <20131009192040.GA5592@mtj.dyndns.org> <1381352311.5429.115.camel@misato.fc.hp.com> <20131009211136.GH5592@mtj.dyndns.org> <1381363135.5429.138.camel@misato.fc.hp.com> <20131010010029.GA10900@mtj.dyndns.org> <1381415809.24268.40.camel@misato.fc.hp.com> <20131010153518.GB13276@htj.dyndns.org> <1381422249.24268.68.camel@misato.fc.hp.com> <20131010164623.GD13276@htj.dyndns.org> <1381423840.24268.70.camel@misato.fc.hp.com> <20131010165522.GE13276@htj.dyndns.org> <1381424390.26234.1.camel@misato.fc.hp.com> <5256E01B.9050802@zytor.com> Content-Type: text/plain; charset="UTF-8" Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: "H. Peter Anvin" Cc: Tejun Heo , Zhang Yanfei , Andrew Morton , "Rafael J . Wysocki" , "lenb@kernel.org" , Thomas Gleixner , "mingo@elte.hu" , Wanpeng Li , Thomas Renninger , Yinghai Lu , Jiang Liu , Wen Congyang , Lai Jiangshan , "isimatu.yasuaki@jp.fujitsu.com" , "izumi.taku@jp.fujitsu.com" , Mel Gorman , Minchan Kim , "mina86@mina86.com" , "gong.chen@linux.intel.com" , "vasilis.liaskovitis@profitbricks.com" , "lwoodman@redhat.com" , Rik van Riel , "jweiner@redhat.com" , "prarit@redhat.com" , "x86@kernel.org" , "linux-doc@vger.kernel.org" , "linux-kernel@vger.kernel.org" , Linux MM , "linux-acpi@vger.kernel.org" , "imtangchen@gmail.com" , Zhang Yanfei , Tang Chen On Thu, 2013-10-10 at 10:12 -0700, H. Peter Anvin wrote: > On 10/10/2013 09:59 AM, Toshi Kani wrote: > > On Thu, 2013-10-10 at 12:55 -0400, Tejun Heo wrote: > >> On Thu, Oct 10, 2013 at 10:50:40AM -0600, Toshi Kani wrote: > >>> Can you elaborate why we need to parse the device hierarchy before > >>> setting up page tables? > >> > >> How else can one put the page tables on the "local device"? Am I > >> missing something? > > > > The local page table item is gone under the current plan as you > > suggested... > > > > That would be a significant performance regression. In earlier discussions, Tejun pointed out that huge mappings dismiss the benefit of local page tables. https://lkml.org/lkml/2013/8/23/245 Thanks, -Toshi -- 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