From: Matteo Croce <technoboy85@gmail.com>
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
Subject: Re: [tip:x86/cpu] x86: AMD Geode LX optimizations
Date: Mon, 1 Mar 2010 23:18:53 +0100 [thread overview]
Message-ID: <40101cc31003011418r3ea15f1bg285ddda7681cf8f9@mail.gmail.com> (raw)
In-Reply-To: <tip-98059e3463383b18fd79181179cd539b74846b47@git.kernel.org>
On Fri, Oct 2, 2009 at 7:27 PM, tip-bot for Matteo Croce
<technoboy85@gmail.com> wrote:
> Commit-ID: 98059e3463383b18fd79181179cd539b74846b47
> Gitweb: http://git.kernel.org/tip/98059e3463383b18fd79181179cd539b74846b47
> Author: Matteo Croce <technoboy85@gmail.com>
> AuthorDate: Thu, 1 Oct 2009 17:11:10 +0200
> Committer: H. Peter Anvin <hpa@zytor.com>
> 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 <technoboy85@gmail.com>
> LKML-Reference: <40101cc30910010811v5d15ff4cx9dd57c9cc9b4b045@mail.gmail.com>
> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
>
>
> ---
> 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 <technoboy85@gmail.com>
--- 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
prev parent reply other threads:[~2010-03-01 22:19 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2009-10-01 15:11 [PATCH] " Matteo Croce
2009-10-02 18:27 ` [tip:x86/cpu] x86: " tip-bot for Matteo Croce
2010-03-01 22:18 ` Matteo Croce [this message]
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=40101cc31003011418r3ea15f1bg285ddda7681cf8f9@mail.gmail.com \
--to=technoboy85@gmail.com \
--cc=hpa@zytor.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-tip-commits@vger.kernel.org \
--cc=mingo@redhat.com \
--cc=tglx@linutronix.de \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox
all inboxes | Powered by JetHome®