From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S965716AbXCPRIt (ORCPT ); Fri, 16 Mar 2007 13:08:49 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S965712AbXCPRIt (ORCPT ); Fri, 16 Mar 2007 13:08:49 -0400 Received: from gw.goop.org ([64.81.55.164]:33616 "EHLO mail.goop.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S965716AbXCPRIs (ORCPT ); Fri, 16 Mar 2007 13:08:48 -0400 Message-ID: <45FACF1B.5010709@goop.org> Date: Fri, 16 Mar 2007 10:08:43 -0700 From: Jeremy Fitzhardinge User-Agent: Thunderbird 1.5.0.10 (X11/20070302) MIME-Version: 1.0 To: Ingo Molnar CC: Andi Kleen , Andrew Morton , linux-kernel@vger.kernel.org, virtualization@lists.osdl.org, xen-devel@lists.xensource.com, Chris Wright , Zachary Amsden , Rusty Russell , Ian Pratt , Christian Limpach , Christoph Lameter Subject: Re: [patch 15/26] Xen-paravirt_ops: Add apply_to_page_range() which applies a function to a pte range. References: <20070301232443.195603797@goop.org> <20070301232528.155002121@goop.org> <20070316091940.GJ23174@elte.hu> In-Reply-To: <20070316091940.GJ23174@elte.hu> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Ingo Molnar wrote: > nice one! I suspect we could simplify some of the less > performance-critical open-coded pagetable walker loops in the kernel > with this? (i'm not even sure it's all that much of a performance loss > to pass a function pointer around - would be nice to convert say > mprotect() to this and see the performance difference?) > apply_page_to_range has the side-effect of allocating all the pagetable levels for the address range it walks. Xen uses this to populate pagetables (for example, build out the pagetable, and let the hypervisor plug a mapping into the pte page). If that's OK for the other uses, then it should be good. J