From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756330Ab3BAPO1 (ORCPT ); Fri, 1 Feb 2013 10:14:27 -0500 Received: from caramon.arm.linux.org.uk ([78.32.30.218]:33068 "EHLO caramon.arm.linux.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756128Ab3BAPOY (ORCPT ); Fri, 1 Feb 2013 10:14:24 -0500 Date: Fri, 1 Feb 2013 15:14:10 +0000 From: Russell King - ARM Linux To: Cyril Chemparathy Cc: Nicolas Pitre , linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, sboyd@codeaurora.org, Will Deacon , paulmck@linux.vnet.ibm.com, Catalin Marinas , marc.zyngier@arm.com, linus.walleij@linaro.org Subject: Re: [PATCH v4 00/13] ARM LPAE Fixes - Part 1 Message-ID: <20130201151410.GR23505@n2100.arm.linux.org.uk> References: <1359669512-31276-1-git-send-email-cyril@ti.com> <510BDAED.8060805@ti.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <510BDAED.8060805@ti.com> User-Agent: Mutt/1.5.19 (2009-01-05) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Feb 01, 2013 at 10:10:37AM -0500, Cyril Chemparathy wrote: > With this, I ran simple network and filesystem performance tests to > compare the code-patching vs. non-code-patching variants. These tests > didn't yield any significant performance difference between the two on > an ARMv7 (Cortex-A8) platform. It's not network and fs activity that this kind of stuff is likely to show up in, but more to do with walking pages tables and the like - remember that page tables are stored using physical addresses, and any walks of them have to convert those physical addresses to virtual addresses and back again. So, things like page scanning for eviction (eg, page aging, page faults even those which just re-use a page from the page cache) have to use the v:p / p:v translation macros.