Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932149AbWIGQBm (ORCPT ); Thu, 7 Sep 2006 12:01:42 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932246AbWIGQBm (ORCPT ); Thu, 7 Sep 2006 12:01:42 -0400 Received: from srv5.dvmed.net ([207.36.208.214]:6041 "EHLO mail.dvmed.net") by vger.kernel.org with ESMTP id S932149AbWIGQBk (ORCPT ); Thu, 7 Sep 2006 12:01:40 -0400 Message-ID: <45004227.8090200@pobox.com> Date: Thu, 07 Sep 2006 12:00:39 -0400 From: Jeff Garzik User-Agent: Thunderbird 1.5.0.5 (X11/20060808) MIME-Version: 1.0 To: Tejun Heo CC: Grant Grundler , Matthew Wilcox , Arjan van de Ven , linux-pci@atrey.karlin.mff.cuni.cz, Greg KH , lkml Subject: Re: question regarding cacheline size References: <44FFD8C6.8080802@gmail.com> <20060907111120.GL2558@parisc-linux.org> <45000076.4070005@gmail.com> <20060907120756.GA29532@flint.arm.linux.org.uk> <20060907122311.GM2558@parisc-linux.org> <1157632405.14882.27.camel@laptopd505.fenrus.org> <20060907124026.GN2558@parisc-linux.org> <45001665.9050509@gmail.com> <20060907130401.GO2558@parisc-linux.org> <45001C48.6050803@gmail.com> <20060907152147.GA17324@colo.lackof.org> <45003F1B.7000302@gmail.com> In-Reply-To: <45003F1B.7000302@gmail.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit X-Spam-Score: -4.2 (----) X-Spam-Report: SpamAssassin version 3.1.3 on srv5.dvmed.net summary: Content analysis details: (-4.2 points, 5.0 required) Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 941 Lines: 26 Tejun Heo wrote: > arch/i386/pci/common.c overrides cacheline size to min 32 regardless of > actual size. So, we seem to be using larger cacheline size for MWI > already. It clamps the minimum size to 32, yes, but on modern machines common.c configures it to a larger size. > Jeff pointed out that there actually are devices which limit CLS config. > IMHO, making PCI configure CLS automatically and provide helpers to LLD > to override it if necessary should cut it. We still have to add a raft of quirks, if we start automatically configurating CLS... Also, many PCI devices hardcode it to zero. If we start configuring CLS automatically, I forsee a period of breakage... Jeff - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/