From: "David S. Miller" <davem@redhat.com>
To: Grant Grundler <iod00d@hp.com>
Cc: bcrl@kvack.org, tony.luck@intel.com, davidm@hpl.hp.com,
davidm@napali.hpl.hp.com, peter@chubb.wattle.id.au, ak@suse.de,
iod00d@hp.com, peterc@gelato.unsw.edu.au,
linux-ns83820@kvack.org, linux-ia64@vger.kernel.org,
linux-kernel@vger.kernel.org
Subject: Re: NS83820 2.6.0-test5 driver seems unstable on IA64
Date: Tue, 23 Sep 2003 11:51:22 -0700 [thread overview]
Message-ID: <20030923115122.41b7178f.davem@redhat.com> (raw)
In-Reply-To: <20030923185104.GA8477@cup.hp.com>
On Tue, 23 Sep 2003 11:51:04 -0700
Grant Grundler <iod00d@hp.com> wrote:
> Even x86 pays at least a one cycle penalty for every misaligned access.
Yes, one cycle, and it's completely lost in the noise when it
happens.
> In general, open source code has no excuse for using misaligned fields.
> It's (mostly) avoidable. TCP/IP headers are the historical exception.
It's not the TCP/IP headers intrinsically, it's what they are embedded
inside of.
For example, if the ethernet driver (as nearly all of our's do which
can) optimized for an ethernet header followed by an IP header, guess
what? That causes ethernet header followed by appletalk followed
by IP to do unaligned accesses.
It is an unavoidable axoim in the kernel networking. Unaligned accesses
will happen, and they aren't a bug and therefore not worthy of mention
in the kernel logs any more than "page was freed" :-)
next prev parent reply other threads:[~2003-09-23 19:07 UTC|newest]
Thread overview: 82+ messages / expand[flat|nested] mbox.gz Atom feed top
2003-09-23 18:21 NS83820 2.6.0-test5 driver seems unstable on IA64 Luck, Tony
2003-09-23 18:29 ` Benjamin LaHaise
2003-09-23 18:45 ` David S. Miller
2003-09-23 18:51 ` Grant Grundler
2003-09-23 18:51 ` David S. Miller [this message]
2003-09-23 20:38 ` Grant Grundler
2003-09-23 20:45 ` David S. Miller
2003-09-23 22:35 ` Grant Grundler
2003-09-23 23:35 ` David S. Miller
2003-09-24 0:13 ` Grant Grundler
2003-09-24 0:04 ` David S. Miller
2003-09-24 2:40 ` [OT] " n0ano
2003-09-24 1:58 ` William Lee Irwin III
2003-09-23 19:04 ` Benjamin LaHaise
2003-09-23 18:54 ` Andreas Schwab
2003-09-23 18:52 ` David S. Miller
2003-09-23 19:09 ` Andreas Schwab
2003-09-23 19:01 ` David S. Miller
2003-09-23 19:16 ` Andreas Schwab
2003-09-23 19:08 ` David S. Miller
2003-09-23 19:28 ` Matthew Wilcox
2003-09-23 19:22 ` David S. Miller
2003-09-23 23:15 ` Andrew Morton
2003-09-23 23:37 ` David S. Miller
2003-09-24 0:14 ` Matthew Wilcox
2003-09-24 0:06 ` David S. Miller
2003-09-23 19:10 ` Jeff Garzik
2003-09-23 19:11 ` Benjamin LaHaise
2003-09-23 19:22 ` Jeff Garzik
2003-09-23 21:00 ` Alan Cox
2003-09-23 21:16 ` David Mosberger
2003-09-24 1:47 ` David S. Miller
[not found] <A4gy.8wi.13@gated-at.bofh.it>
[not found] ` <A4gy.8wi.15@gated-at.bofh.it>
[not found] ` <A4gy.8wi.17@gated-at.bofh.it>
[not found] ` <A4gy.8wi.11@gated-at.bofh.it>
[not found] ` <A4Tv.Ud.37@gated-at.bofh.it>
[not found] ` <AepM.5Zb.41@gated-at.bofh.it>
2003-09-27 4:26 ` Andi Kleen
2003-09-27 4:34 ` David Mosberger
2003-09-27 23:36 ` David S. Miller
[not found] <A2yd.64p.31@gated-at.bofh.it>
[not found] ` <A2yd.64p.29@gated-at.bofh.it>
[not found] ` <A317.6GH.7@gated-at.bofh.it>
2003-09-26 17:04 ` Andi Kleen
2003-09-26 17:22 ` Chris Friesen
2003-09-26 17:47 ` David Mosberger
2003-09-27 3:57 ` David S. Miller
2003-09-27 4:36 ` Andi Kleen
2003-09-27 4:52 ` David Mosberger
[not found] <zU7D.2Ji.27@gated-at.bofh.it>
2003-09-26 15:14 ` Andi Kleen
2003-09-26 15:41 ` David Mosberger
-- strict thread matches above, loose matches on Subject: below --
2003-09-26 6:16 Manfred Spraul
2003-09-26 6:07 ` David S. Miller
2003-09-26 6:41 ` David Mosberger
2003-09-26 14:38 ` Ivan Kokshaysky
2003-09-27 3:12 ` David S. Miller
2003-09-23 22:58 Luck, Tony
2003-09-23 23:32 ` David S. Miller
2003-09-24 5:18 ` Valdis.Kletnieks
2003-09-23 17:58 Van Maren, Kevin
2003-09-23 17:57 ` David S. Miller
2003-09-23 18:27 ` David Mosberger
2003-09-23 18:47 ` David S. Miller
2003-09-23 19:17 ` David Mosberger
2003-09-23 19:10 ` David S. Miller
2003-09-23 20:00 ` David Mosberger
2003-09-24 3:08 ` David S. Miller
2003-09-25 16:11 ` Ivan Kokshaysky
2003-09-26 1:12 ` David S. Miller
2003-09-23 18:06 ` David Mosberger
2003-09-23 19:11 ` David S. Miller
2003-09-19 4:16 Peter Chubb
2003-09-19 4:38 ` Grant Grundler
2003-09-19 4:43 ` Andi Kleen
2003-09-19 5:01 ` Peter Chubb
2003-09-19 5:53 ` Andi Kleen
2003-09-19 10:49 ` Benjamin LaHaise
2003-09-23 0:34 ` Peter Chubb
2003-09-23 0:36 ` Benjamin LaHaise
2003-09-23 6:22 ` David S. Miller
2003-09-23 10:40 ` Peter Chubb
2003-09-23 10:51 ` David S. Miller
2003-09-23 14:59 ` David Mosberger
2003-09-23 17:27 ` David S. Miller
2003-09-23 17:56 ` David Mosberger
2003-09-24 2:55 ` David S. Miller
2003-09-23 23:04 ` Ian Wienand
2003-09-23 23:35 ` David S. Miller
2003-09-19 5:04 ` Grant Grundler
2003-09-19 5:11 ` Peter Chubb
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=20030923115122.41b7178f.davem@redhat.com \
--to=davem@redhat.com \
--cc=ak@suse.de \
--cc=bcrl@kvack.org \
--cc=davidm@hpl.hp.com \
--cc=davidm@napali.hpl.hp.com \
--cc=iod00d@hp.com \
--cc=linux-ia64@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-ns83820@kvack.org \
--cc=peter@chubb.wattle.id.au \
--cc=peterc@gelato.unsw.edu.au \
--cc=tony.luck@intel.com \
/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;
as well as URLs for NNTP newsgroup(s).