From: Parag Warudkar <kernel-stuff@comcast.net>
To: Dave Jones <davej@redhat.com>
Cc: linux-kernel@vger.kernel.org, ak@suse.de
Subject: Re: pci cacheline size / latency oddness.
Date: Mon, 01 Aug 2005 20:41:49 -0400 [thread overview]
Message-ID: <1122943309.26405.7.camel@localhost> (raw)
In-Reply-To: <20050801233517.GA23172@redhat.com>
On Mon, 2005-08-01 at 19:35 -0400, Dave Jones wrote:
> This means we will do the wrong thing on AMD machines which have
> 64 byte cachelines.
pcibios_init (in i386/pci/common.c, which is linked in by X86_64 PCI
code) seems to do this
if (c->x86 >= 6 && c->x86_vendor == X86_VENDOR_AMD)
pci_cache_line_size = 64 >> 2; /* K7 & K8 */
Is it correct to expect all AMD k7/8 machines to have 16 as cache line
size - I thought 64 was more appropriate?
On my Athlon64 laptop, all PCI devices end up having 0 latency.
> x86-64 doesn't have an arch override for pci_cache_line_size
I am trying to fix it up - What's the right way to override it in x86_64
code? Just initialize it to 64 may be?
Parag
next prev parent reply other threads:[~2005-08-02 0:41 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2005-08-01 23:35 pci cacheline size / latency oddness Dave Jones
2005-08-02 0:05 ` Jeff Garzik
2005-08-02 0:41 ` Parag Warudkar [this message]
2005-08-03 13:20 ` Andi Kleen
2005-08-03 10:58 ` Andi Kleen
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=1122943309.26405.7.camel@localhost \
--to=kernel-stuff@comcast.net \
--cc=ak@suse.de \
--cc=davej@redhat.com \
--cc=linux-kernel@vger.kernel.org \
/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