From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758408AbYG2NcR (ORCPT ); Tue, 29 Jul 2008 09:32:17 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753788AbYG2NcH (ORCPT ); Tue, 29 Jul 2008 09:32:07 -0400 Received: from netops-testserver-3-out.sgi.com ([192.48.171.28]:52896 "EHLO relay.sgi.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1753732AbYG2NcG (ORCPT ); Tue, 29 Jul 2008 09:32:06 -0400 Date: Tue, 29 Jul 2008 08:32:04 -0500 From: Cliff Wickman To: Nick Piggin , jeremy@goop.org Cc: steiner@sgi.com, mingo@elte.hu, linux-kernel@vger.kernel.org Subject: Re: Comments on UV tlb flushing Message-ID: <20080729133204.GA13138@sgi.com> References: <488E644B.10801@goop.org> <200807291412.18495.nickpiggin@yahoo.com.au> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <200807291412.18495.nickpiggin@yahoo.com.au> 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 02:12:18PM +1000, Nick Piggin wrote: > On Tuesday 29 July 2008 10:28, Jeremy Fitzhardinge wrote: > > I'm just reworking the x86 tlb code to use smp_call_function_mask, and I > > see how the UV tlb flushing hooks in. A few things occur to me: > > > > 1. There should be a CONFIG_X86_UV to select this code. tlb_uv.o is > > around 6k, which is not trivial overhead to subject every x86_64 > > kernel to. > > Definitely. I'd like to talk about this issue separate from the virtualization one. I think that the Linux distributions are not going to build a special UV kernel, are they? So every distro would have to be prompted to turn on CONFIG_X86_UV, or else their kernel is not going to boot on UV. But you have a point about not linking the 6k UV object file where size is an issue. Thanks for catching that. Perhaps the UV code should be excluded if CONFIG_EMBEDDED is set. -Cliff