From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752573Ab0CAWTR (ORCPT ); Mon, 1 Mar 2010 17:19:17 -0500 Received: from mail-ew0-f220.google.com ([209.85.219.220]:52213 "EHLO mail-ew0-f220.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751057Ab0CAWTP convert rfc822-to-8bit (ORCPT ); Mon, 1 Mar 2010 17:19:15 -0500 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=AMuoJh9b5q1BgW4N8DeLI60i5rN8nb1nTzXS/cCCBYajpECtdQXAzoIUHVxkFkwUB4 6FVK3bPvvHHfatQyPyqnULDX4opnk/FSbEgnb/wLsZVVNX8ByHwa9z1TjE7MxMBjaRlQ uPS7gCSeYT8sXzuTKSNixZOTuFyfx+j/jnEhE= MIME-Version: 1.0 In-Reply-To: References: <40101cc30910010811v5d15ff4cx9dd57c9cc9b4b045@mail.gmail.com> From: Matteo Croce Date: Mon, 1 Mar 2010 23:18:53 +0100 Message-ID: <40101cc31003011418r3ea15f1bg285ddda7681cf8f9@mail.gmail.com> Subject: Re: [tip:x86/cpu] x86: AMD Geode LX optimizations To: linux-tip-commits@vger.kernel.org Cc: linux-kernel@vger.kernel.org, technoboy85@gmail.com, hpa@zytor.com, mingo@redhat.com, tglx@linutronix.de Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8BIT Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Oct 2, 2009 at 7:27 PM, tip-bot for Matteo Croce wrote: > Commit-ID:  98059e3463383b18fd79181179cd539b74846b47 > Gitweb:     http://git.kernel.org/tip/98059e3463383b18fd79181179cd539b74846b47 > Author:     Matteo Croce > AuthorDate: Thu, 1 Oct 2009 17:11:10 +0200 > Committer:  H. Peter Anvin > CommitDate: Fri, 2 Oct 2009 11:24:28 -0700 > > x86: AMD Geode LX optimizations > > Add CPU optimizations for AMD Geode LX. > > Signed-off-by: Matteo Croce > LKML-Reference: <40101cc30910010811v5d15ff4cx9dd57c9cc9b4b045@mail.gmail.com> > Signed-off-by: H. Peter Anvin > > > --- >  arch/x86/Kconfig.cpu     |    2 +- >  arch/x86/Makefile_32.cpu |    2 +- >  2 files changed, 2 insertions(+), 2 deletions(-) > > diff --git a/arch/x86/Kconfig.cpu b/arch/x86/Kconfig.cpu > index 527519b..979de29 100644 > --- a/arch/x86/Kconfig.cpu > +++ b/arch/x86/Kconfig.cpu > @@ -406,7 +406,7 @@ config X86_CMPXCHG64 >  # generates cmov. >  config X86_CMOV >        def_bool y > -       depends on (MK8 || MK7 || MCORE2 || MPENTIUM4 || MPENTIUMM || MPENTIUMIII || MPENTIUMII || M686 || MVIAC3_2 || MVIAC7 || MCRUSOE || MEFFICEON || X86_64 || MATOM) > +       depends on (MK8 || MK7 || MCORE2 || MPENTIUM4 || MPENTIUMM || MPENTIUMIII || MPENTIUMII || M686 || MVIAC3_2 || MVIAC7 || MCRUSOE || MEFFICEON || X86_64 || MATOM || MGEODE_LX) > >  config X86_MINIMUM_CPU_FAMILY >        int > diff --git a/arch/x86/Makefile_32.cpu b/arch/x86/Makefile_32.cpu > index 30e9a26..cbf0776 100644 > --- a/arch/x86/Makefile_32.cpu > +++ b/arch/x86/Makefile_32.cpu > @@ -41,7 +41,7 @@ cflags-$(CONFIG_X86_ELAN)     += -march=i486 > >  # Geode GX1 support >  cflags-$(CONFIG_MGEODEGX1)     += -march=pentium-mmx > - > +cflags-$(CONFIG_MGEODE_LX)     += $(call cc-option,-march=geode,-march=pentium-mmx) >  # add at the end to overwrite eventual tuning options from earlier >  # cpu entries >  cflags-$(CONFIG_X86_GENERIC)   += $(call tune,generic,$(call tune,i686)) > Unfortunately it seems that GCC produces slower code with -march=geode and that the fastest code is generated with -march=i686: http://gcc.gnu.org/bugzilla/show_bug.cgi?id=41989 We have two possible solutions: revert the flags or wait for the GCC folks to fix the compiler. In the meantime I discovered that even the older Geode GX does have CMOV and MMX so have a look at this new patch Signed-off-by: Matteo Croce --- a/arch/x86/Kconfig.cpu 2010-03-01 00:45:39.484611338 +0100 +++ b/arch/x86/Kconfig.cpu 2010-03-01 00:46:08.776560999 +0100 @@ -402,7 +402,7 @@ # generates cmov. config X86_CMOV def_bool y - depends on (MK8 || MK7 || MCORE2 || MPENTIUM4 || MPENTIUMM || MPENTIUMIII || MPENTIUMII || M686 || MVIAC3_2 || MVIAC7 || MCRUSOE || MEFFICEON || X86_64 || MATOM || MGEODE_LX) + depends on (MK8 || MK7 || MCORE2 || MPENTIUM4 || MPENTIUMM || MPENTIUMIII || MPENTIUMII || M686 || MVIAC3_2 || MVIAC7 || MCRUSOE || MEFFICEON || X86_64 || MATOM || MGEODEGX1 || MGEODE_LX) config X86_MINIMUM_CPU_FAMILY int --- a/arch/x86/Makefile_32.cpu 2010-03-01 00:44:07.948526792 +0100 +++ b/arch/x86/Makefile_32.cpu 2010-03-01 23:15:48.503698008 +0100 @@ -40,7 +40,7 @@ cflags-$(CONFIG_X86_ELAN) += -march=i486 # Geode GX1 support -cflags-$(CONFIG_MGEODEGX1) += -march=pentium-mmx +cflags-$(CONFIG_MGEODEGX1) += $(call cc-option,-march=geode,-march=pentium-mmx) cflags-$(CONFIG_MGEODE_LX) += $(call cc-option,-march=geode,-march=pentium-mmx) # add at the end to overwrite eventual tuning options from earlier # cpu entries