From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755169Ab1GFSVY (ORCPT ); Wed, 6 Jul 2011 14:21:24 -0400 Received: from terminus.zytor.com ([198.137.202.10]:58686 "EHLO mail.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754008Ab1GFSVX (ORCPT ); Wed, 6 Jul 2011 14:21:23 -0400 Message-ID: <4E14A781.8090004@zytor.com> Date: Wed, 06 Jul 2011 11:20:49 -0700 From: "H. Peter Anvin" User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.2.17) Gecko/20110428 Fedora/3.1.10-1.fc15 Thunderbird/3.1.10 MIME-Version: 1.0 To: Andi Kleen CC: Frederic Weisbecker , Jan Beulich , Peter Zijlstra , Ingo Molnar , Thomas Gleixner , Arnaldo Carvalho de Melo , LKML Subject: Re: [PATCH 3/6] x86,64: Simplify save_regs() References: <1309624184-9790-1-git-send-email-fweisbec@gmail.com> <1309624184-9790-4-git-send-email-fweisbec@gmail.com> <4E1185F3020000780004BF21@nat28.tlf.novell.com> <20110704125742.GB1915@somewhere.redhat.com> In-Reply-To: Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 07/06/2011 10:34 AM, Andi Kleen wrote: > Frederic Weisbecker writes: >> >> I really did not think about code duplication, considering >> it's better to optimize the irq entry path. >> >> What do you guys think? We can still revert the whole patchset. > > FWIW I think it should be a macro, like it was in the original code. > > Optimizing entry*.S for code size doesn't make a lot of sense. > Code size, no. *Path* size and cache/prefetch friendliness is another matter. The subroutine is bad on that account, too, so yes, this really seems like a losing proposition. I'm not too fond of the gajillion obtuse macros we have, but subroutines doesn't make it really any better. -hpa