From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932120AbWJ2JQI (ORCPT ); Sun, 29 Oct 2006 04:16:08 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932121AbWJ2JQI (ORCPT ); Sun, 29 Oct 2006 04:16:08 -0500 Received: from mis011-1.exch011.intermedia.net ([64.78.21.128]:48249 "EHLO mis011-1.exch011.intermedia.net") by vger.kernel.org with ESMTP id S932120AbWJ2JQE (ORCPT ); Sun, 29 Oct 2006 04:16:04 -0500 Message-ID: <4544714F.7070203@qumranet.com> Date: Sun, 29 Oct 2006 11:15:59 +0200 From: Avi Kivity User-Agent: Thunderbird 1.5.0.7 (X11/20061008) MIME-Version: 1.0 To: Anthony Liguori CC: Arnd Bergmann , kvm-devel@lists.sourceforge.net, linux-kernel@vger.kernel.org Subject: Re: [kvm-devel] [PATCH 6/13] KVM: memory slot management References: <4540EE2B.9020606@qumranet.com> <200610270044.31382.arnd@arndb.de> <45419D73.1070106@qumranet.com> <200610270937.11646.arnd@arndb.de> <454208EB.7080007@qumranet.com> <4542292C.3080409@us.ibm.com> In-Reply-To: <4542292C.3080409@us.ibm.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit X-OriginalArrivalTime: 29 Oct 2006 09:16:04.0276 (UTC) FILETIME=[DBE87F40:01C6FB3A] Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Anthony Liguori wrote: >> >> It's not about tlb entries. The shadow page tables collaples a GV -> >> HV -> HP double translation into a GV -> HP page table. When the >> Linux vm goes around evicting pages, it invalidates those mappings. >> >> There are two solutions possible: lock pages which participate in >> these translations (and their number can be large) or modify the >> Linux vm to consult a reverse mapping and remove the translations (in >> which case TLB entries need to be removed). >> > > If you locked pages that have active shadow mappings, you could then > use a secondary mechanism to invalidate existing mappings when necessary. > Yes. There are two needs: to propagate virtual machine activity to the host (by folding dirty and accessed bits from multiple shadow ptes into a single struct page), and to apply pressure from the vm to the guest (by invalidating all mappings of a given page). -- error compiling committee.c: too many arguments to function From mboxrd@z Thu Jan 1 00:00:00 1970 From: Avi Kivity Subject: Re: [PATCH 6/13] KVM: memory slot management Date: Sun, 29 Oct 2006 11:15:59 +0200 Message-ID: <4544714F.7070203@qumranet.com> References: <4540EE2B.9020606@qumranet.com> <200610270044.31382.arnd@arndb.de> <45419D73.1070106@qumranet.com> <200610270937.11646.arnd@arndb.de> <454208EB.7080007@qumranet.com> <4542292C.3080409@us.ibm.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Cc: kvm-devel-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org Return-path: To: Anthony Liguori In-Reply-To: <4542292C.3080409-r/Jw6+rmf7HQT0dZR+AlfA@public.gmane.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: kvm-devel-bounces-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org Errors-To: kvm-devel-bounces-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org List-Id: kvm.vger.kernel.org Anthony Liguori wrote: >> >> It's not about tlb entries. The shadow page tables collaples a GV -> >> HV -> HP double translation into a GV -> HP page table. When the >> Linux vm goes around evicting pages, it invalidates those mappings. >> >> There are two solutions possible: lock pages which participate in >> these translations (and their number can be large) or modify the >> Linux vm to consult a reverse mapping and remove the translations (in >> which case TLB entries need to be removed). >> > > If you locked pages that have active shadow mappings, you could then > use a secondary mechanism to invalidate existing mappings when necessary. > Yes. There are two needs: to propagate virtual machine activity to the host (by folding dirty and accessed bits from multiple shadow ptes into a single struct page), and to apply pressure from the vm to the guest (by invalidating all mappings of a given page). -- error compiling committee.c: too many arguments to function ------------------------------------------------------------------------- Using Tomcat but need to do more? Need to support web services, security? Get stuff done quickly with pre-integrated technology to make your job easier Download IBM WebSphere Application Server v.1.0.1 based on Apache Geronimo http://sel.as-us.falkag.net/sel?cmd=lnk&kid=120709&bid=263057&dat=121642