Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752720Ab2JLXRY (ORCPT ); Fri, 12 Oct 2012 19:17:24 -0400 Received: from mail.skyhub.de ([78.46.96.112]:60726 "EHLO mail.skyhub.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751727Ab2JLXRX (ORCPT ); Fri, 12 Oct 2012 19:17:23 -0400 Date: Sat, 13 Oct 2012 01:17:19 +0200 From: Borislav Petkov To: George Spelvin Cc: linux-kernel@vger.kernel.org, Ma Ling , x86@kernel.org Subject: Re: [PATCH RFC 2/2] [x86] Optimize copy_page by re-arranging instruction sequence and saving register Message-ID: <20121012231719.GA21198@liondog.tnic> Mail-Followup-To: Borislav Petkov , George Spelvin , linux-kernel@vger.kernel.org, Ma Ling , x86@kernel.org References: <20121012210257.11451.qmail@science.horizon.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20121012210257.11451.qmail@science.horizon.com> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 829 Lines: 24 On Fri, Oct 12, 2012 at 05:02:57PM -0400, George Spelvin wrote: > Here are some Phenom results for that benchmark. The average time > increases from 700 to 760 cycles (+8.6%). I was afraid something like that would show up. Btw, in looking at this more and IINM, we use the REP MOVSQ version on AMD anyway because of X86_FEATURE_REP_GOOD being set on some K8 and everything from F10h on. So, actually this µbenchmark should be comparing the REP MOVSQ case too and the changes to the unrolled copy_page shouldn't concern AMD boxes actually... Hmm. -- Regards/Gruss, Boris. -- 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/