netdev.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: William Allen Simpson <william.allen.simpson@gmail.com>
To: Patrick McHardy <kaber@trash.net>
Cc: "Joe Perches" <joe@perches.com>,
	"Andi Kleen" <andi@firstfloor.org>,
	"Linux Kernel Developers" <linux-kernel@vger.kernel.org>,
	"Linux Kernel Network Developers" <netdev@vger.kernel.org>,
	"Ilpo Järvinen" <ilpo.jarvinen@helsinki.fi>,
	"Eric Dumazet" <eric.dumazet@gmail.com>
Subject: Re: [PATCH v4] tcp: harmonize tcp_vx_rcv header length assumptions
Date: Thu, 14 Jan 2010 10:02:03 -0500	[thread overview]
Message-ID: <4B4F31EB.1000004@gmail.com> (raw)
In-Reply-To: <4B4ED830.4040407@trash.net>

Patrick McHardy wrote:
> In IPv6 it is released in ip6_input.c before the packet is handed to
> the protocol handler.
> 
Thanks, I made a note of it.

Thanks to Andi, I've been using his suggestion to compare the IPv4 and
IPv6 generated code.  Another minor difference between them was IPv4
stored *iph.

So, I added *ip6h, and discovered that it made the code longer.  Later
inline function invocations had also calculated it, so adding it merely
calculated it earlier and stored it.  The code thrashes registers
making room for the additional variable.  I'm guessing that the IPv6
folks had already looked at the issue....  Good work!

So, I tried removing *iph, and that shrunk the IPv4 code some, too.

Thanks to everybody for their comments and review.

  reply	other threads:[~2010-01-14 15:02 UTC|newest]

Thread overview: 23+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2010-01-10 13:02 query: redundant tcp header length checks? William Allen Simpson
2010-01-12 10:05 ` [PATCH] tcp: harmonize tcp_vx_rcv header length assumptions William Allen Simpson
2010-01-12 10:46   ` Eric Dumazet
2010-01-12 17:11     ` William Allen Simpson
2010-01-13  9:50       ` William Allen Simpson
2010-01-12 17:14     ` William Allen Simpson
2010-01-13 10:48 ` [PATCH v4] " William Allen Simpson
2010-01-13 11:56   ` Andi Kleen
2010-01-13 15:36     ` William Allen Simpson
2010-01-13 15:53       ` Andi Kleen
2010-01-13 16:40         ` [PATCH] Makefile: Document ability to make file.lst and file.S Joe Perches
2010-01-13 17:14           ` Andi Kleen
2010-01-13 17:31             ` Joe Perches
2010-01-13 19:51               ` William Allen Simpson
2010-01-14  3:26               ` Américo Wang
2010-01-18 12:29               ` Michal Marek
2010-01-13 19:49         ` [PATCH v4] tcp: harmonize tcp_vx_rcv header length assumptions William Allen Simpson
2010-01-13 20:19           ` Andi Kleen
2010-01-13 21:13           ` William Allen Simpson
2010-01-14  1:03             ` Joe Perches
2010-01-14  8:39               ` Patrick McHardy
2010-01-14 15:02                 ` William Allen Simpson [this message]
2010-01-14 15:10 ` [PATCH v5] " William Allen Simpson

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=4B4F31EB.1000004@gmail.com \
    --to=william.allen.simpson@gmail.com \
    --cc=andi@firstfloor.org \
    --cc=eric.dumazet@gmail.com \
    --cc=ilpo.jarvinen@helsinki.fi \
    --cc=joe@perches.com \
    --cc=kaber@trash.net \
    --cc=linux-kernel@vger.kernel.org \
    --cc=netdev@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;
as well as URLs for NNTP newsgroup(s).