Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753448AbZDGIJg (ORCPT ); Tue, 7 Apr 2009 04:09:36 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752048AbZDGIJS (ORCPT ); Tue, 7 Apr 2009 04:09:18 -0400 Received: from smtp-out.google.com ([216.239.45.13]:13489 "EHLO smtp-out.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751835AbZDGIJP (ORCPT ); Tue, 7 Apr 2009 04:09:15 -0400 DomainKey-Signature: a=rsa-sha1; s=beta; d=google.com; c=nofws; q=dns; h=date:from:x-x-sender:to:cc:subject:in-reply-to:message-id: references:user-agent:mime-version:content-type:x-system-of-record; b=Kp4eL1CGbV+CZyBpkWngpdvbRzyr7Mp2Gd9z9FnzuAvgqeytLH7y6kYmHiHarFDTj A8TKMawSOPMdqWNL6N25g== Date: Tue, 7 Apr 2009 01:08:59 -0700 (PDT) From: David Rientjes X-X-Sender: rientjes@chino.kir.corp.google.com To: Andi Kleen cc: Brice Goglin , KOSAKI Motohiro , Yinghai Lu , Chris Worley , linux-kernel@vger.kernel.org Subject: Re: Off topic: Numactl "distance" wrong In-Reply-To: <20090407075908.GL17934@one.firstfloor.org> Message-ID: References: <86802c440904031448yc6d499ckd9cb969ce136f477@mail.gmail.com> <87r609jtc2.fsf@basil.nowhere.org> <20090407111539.F0F5.A69D9226@jp.fujitsu.com> <49DAF003.1070605@inria.fr> <20090407070530.GJ17934@one.firstfloor.org> <20090407075908.GL17934@one.firstfloor.org> User-Agent: Alpine 2.00 (DEB 1167 2008-08-23) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII X-System-Of-Record: true Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1593 Lines: 39 On Tue, 7 Apr 2009, Andi Kleen wrote: > > It would also be possible to verify that the distance between two > > localities is described consistently in the table (like in the following > > patch). > > Do you have an real-world example where this is wrong? > Um, this is a SLIT validation method, so the change is only necessary to ensure that the table is actually valid unless affinity is not symmetric in both directions between localities. Do you have a real-world example of the firmware handing off a locality that less than LOCAL_DISTANCE? If so, that would violate the specification since values 0-9 are reserved. But the validation method still checks and you're not arguing against it, right? slit_valid() is intended to prevent invalid tables from being used because they are incorrect and, thus, can't possibly be used the describe the physical topology. > In general this thread seems to contain much more speculation than > facts. > The fact, which you seem to be ignoring, is node hotplug would require this table to change anyway. It's quite possible using an _SLI method to dynamically reconfigure the localities, including those that were statically described by the BIOS at boot. So while you may be satisfied with the ACPI 2.0 way of thinking, machines have actually changed in the last five years. -- 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/