From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758181AbYG2UFH (ORCPT ); Tue, 29 Jul 2008 16:05:07 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751955AbYG2UE4 (ORCPT ); Tue, 29 Jul 2008 16:04:56 -0400 Received: from netops-testserver-3-out.sgi.com ([192.48.171.28]:38133 "EHLO relay.sgi.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1750897AbYG2UE4 (ORCPT ); Tue, 29 Jul 2008 16:04:56 -0400 Date: Tue, 29 Jul 2008 15:04:55 -0500 From: Cliff Wickman To: Jeremy Fitzhardinge Cc: Nick Piggin , steiner@sgi.com, mingo@elte.hu, linux-kernel@vger.kernel.org Subject: Re: Comments on UV tlb flushing Message-ID: <20080729200455.GA20559@sgi.com> References: <488E644B.10801@goop.org> <200807291412.18495.nickpiggin@yahoo.com.au> <20080729133204.GA13138@sgi.com> <488F2C9B.9070306@goop.org> <20080729173420.GA18296@sgi.com> <488F5781.2030909@goop.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <488F5781.2030909@goop.org> User-Agent: Mutt/1.5.17+20080114 (2008-01-14) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Jul 29, 2008 at 10:46:41AM -0700, Jeremy Fitzhardinge wrote: > Cliff Wickman wrote: >> But if the tlb_uv.o code should be present in "every" distro x86 kernel >> I don't see the point of having to configure it in. Why not just >> configure it out for small (embedded) kernels? > > Because it's not an binary thing. Lots of people who are compiling > their own kernels for specialized uses don't set CONFIG_EMBEDDED, but > also don't want a kitchen sink kernel. 6k isn't that much, but if every > obscure platform enabled some always-on code it rapidly starts to build > up. But UV will not be obscure! It will be common among x86_64 :) I know what you're talking about. It may sometimes be useful to turn off chunks of code you don't need. But is the specialized application of 64-bit processors big enough to warrant the feature? The size of most any 64-bit system would, I would think, make 6k of code insignificant. And the more options you add, the more likely someone will pick combinations that won't work together. > Basically, if you want to make sure if you're going to get some level of > distro support, you need to make contact with the distros directly and > talk about what you'd like them to do. > J And we do. And could reasonably expect that they would turn on that option for x86_64 kernels. We'd just, of course, rather not have to watch and prompt to be sure all x86_64 kernels will run on our hardware. -Cliff -- Cliff Wickman Silicon Graphics, Inc. cpw@sgi.com (651) 683-3824