Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754681AbZKHRrB (ORCPT ); Sun, 8 Nov 2009 12:47:01 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753953AbZKHRrB (ORCPT ); Sun, 8 Nov 2009 12:47:01 -0500 Received: from mail-fx0-f221.google.com ([209.85.220.221]:52201 "EHLO mail-fx0-f221.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753313AbZKHRrA convert rfc822-to-8bit (ORCPT ); Sun, 8 Nov 2009 12:47:00 -0500 X-Greylist: delayed 399 seconds by postgrey-1.27 at vger.kernel.org; Sun, 08 Nov 2009 12:47:00 EST DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:in-reply-to:references:from:date:message-id:subject:to :cc:content-type:content-transfer-encoding; b=DRf6IzlqEgMpZNpzxl9FNLD52iFow12mqJEhdC54y1+pHxqOipaeOQPGMLqqbvqPzx 7Pb12dInVCg6kSojE7EKtLiC7HQjJJ8qJxiTUtCxZ46F8CXYdAHuvzbrStbH4rvM6Kvg hihiT6qJ0N4kYbevFFOHa+3o/memWEGAO64sI= MIME-Version: 1.0 In-Reply-To: <20091108173708.GF1372@ucw.cz> References: <40101cc30910021912r17b3a08bue1b9412e4fa47d89@mail.gmail.com> <20091003072127.GC21407@elte.hu> <40101cc30911060659k7b3b6428ob1340e476bdbac5b@mail.gmail.com> <4AF4526B.4060101@zytor.com> <40101cc30911061418w357b74d8i3bf9a9537de052d4@mail.gmail.com> <20091108173708.GF1372@ucw.cz> From: Matteo Croce Date: Sun, 8 Nov 2009 18:40:06 +0100 Message-ID: <40101cc30911080940s18eb26bbg641beeaddbc25c3d@mail.gmail.com> Subject: Re: i686 quirk for AMD Geode To: Pavel Machek Cc: "H. Peter Anvin" , Ingo Molnar , linux-kernel@vger.kernel.org Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 8BIT Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2092 Lines: 52 On Sun, Nov 8, 2009 at 6:37 PM, Pavel Machek wrote: > On Fri 2009-11-06 23:18:06, Matteo Croce wrote: >> On Fri, Nov 6, 2009 at 5:44 PM, H. Peter Anvin wrote: >> > On 11/06/2009 06:59 AM, Matteo Croce wrote: >> >> indeed it has MMX, MMXEXT and CMOV, just lacks the long NOP instruction (NOPL). >> > >> > MMX and MMXEXT are hardly hallmarks of i686, which leaves only cmov. >> > I'm somewhat wondering about the general value of this patch; is i686 >> > code really that much faster on Geode that it's worth it? >> > >> > ? ? ? ?-hpa >> > >> > -- >> > H. Peter Anvin, Intel Open Source Technology Center >> > I work for Intel. ?I don't speak on their behalf. >> > >> > >> >> yes, I did some test like gzip, bzip2, lame etc and they give more or less >> the same results of dhrystone >> >> root@alix:/usr/src# CFLAGS='-march=i586' ./dry.c >> Microseconds for one run through Dhrystone: ? ? ? ?1.4 >> Dhrystones per Second: ? ? ? ? ? ? ? ? ? ? ? ? ?740741 > ... >> root@alix:/usr/src# CFLAGS='-march=i686' ./dry.c >> Trying 5000000 runs through Dhrystone: >> Microseconds for one run through Dhrystone: ? ? ? ?1.2 >> Dhrystones per Second: ? ? ? ? ? ? ? ? ? ? ? ? ?841751 > > Teach gcc that geodelx exists? No need to break kernel for that... and > you probably can gain even bigger gains. > ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?Pavel Gcc 4.4 already knows about it, just sucks at optimizing: # CFLAGS='-march=geode' ./dry.c gcc -c -O3 -march=geode ./dry.c -o dry1.o gcc -DPASS2 -O3 -march=geode ./dry.c dry1.o -o dry2 Dhrystone Benchmark, Version C, Version 2.2 Program compiled without 'register' attribute Using times(), HZ=100 Trying 5000000 runs through Dhrystone: Microseconds for one run through Dhrystone: 1.4 Dhrystones per Second: 719424 -- 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/