Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758618AbZKJWhh (ORCPT ); Tue, 10 Nov 2009 17:37:37 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1758531AbZKJWhe (ORCPT ); Tue, 10 Nov 2009 17:37:34 -0500 Received: from terminus.zytor.com ([198.137.202.10]:41299 "EHLO terminus.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758440AbZKJWg5 (ORCPT ); Tue, 10 Nov 2009 17:36:57 -0500 Message-ID: <4AF9E94D.5040601@zytor.com> Date: Tue, 10 Nov 2009 14:29:33 -0800 From: "H. Peter Anvin" User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.1.4pre) Gecko/20091014 Fedora/3.0-2.8.b4.fc11 Thunderbird/3.0b4 MIME-Version: 1.0 To: Lennart Sorensen CC: Willy Tarreau , Pavel Machek , Avi Kivity , Alan Cox , Matteo Croce , Sven-Haegar Koch , Ingo Molnar , linux-kernel@vger.kernel.org Subject: Re: i686 quirk for AMD Geode References: <20091110105642.215804e0@lxorguk.ukuu.org.uk> <4AF99E04.8080704@zytor.com> <20091110172454.3c4481f2@lxorguk.ukuu.org.uk> <4AF9B5AB.5010800@zytor.com> <4AF9C3EF.6000705@redhat.com> <4AF9C6AB.8080006@zytor.com> <20091110201602.GA26633@1wt.eu> <20091110205445.GB1407@ucw.cz> <20091110211259.GD26633@1wt.eu> <4AF9D8E2.7050205@zytor.com> <20091110222756.GF15159@caffeine.csclub.uwaterloo.ca> In-Reply-To: <20091110222756.GF15159@caffeine.csclub.uwaterloo.ca> 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 Content-Length: 999 Lines: 24 On 11/10/2009 02:27 PM, Lennart Sorensen wrote: > On Tue, Nov 10, 2009 at 01:19:30PM -0800, H. Peter Anvin wrote: >> Willy, perhaps you can come up with a list of features you think should >> be emulated, together with an explanation of why you opted for that list >> of features and *did not* opt for others. >> >> Note: emulated FPU is a special subcase. The FPU operations are >> heavyweight enough that the overhead of trapping versus library calls is >> relatively insignificant. > > That doesn't seem to be the experience of the arm EABI versus the old > arm ABI with kernel FPU emulation. Using user space library calls for > FPU is vastly faster than the trapping and kernel FPU emulation. I don't believe we were talking about ARM. -hpa -- 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/