From: "David S. Miller" <davem@davemloft.net>
To: Herbert Xu <herbert@gondor.apana.org.au>
Cc: jgarzik@pobox.com, thomas.spatzier@de.ibm.com, netdev@oss.sgi.com
Subject: Re: [PATCH] select appropriate skb size in tcp_sendmsg when TSO is used
Date: Tue, 26 Oct 2004 17:55:53 -0700 [thread overview]
Message-ID: <20041026175553.55a1b72d.davem@davemloft.net> (raw)
In-Reply-To: <20041027002209.GA5002@gondor.apana.org.au>
On Wed, 27 Oct 2004 10:22:09 +1000
Herbert Xu <herbert@gondor.apana.org.au> wrote:
> On Tue, Oct 26, 2004 at 08:15:31PM -0400, Jeff Garzik wrote:
> >
> > > IMHO it is valid to disable SG without disabling checksums, no?
> >
> > It's useless: The packet header is always in a separate memory
> > location from the packet data, when using zerocopy sendfile(2).
> >
> > When not using zerocopy sendfile, you are copying the data _anyway_.
>
> I'm fine with adding this check. However I think that belongs in
> another patch since we don't check that in register_netdev currently.
>
> Dave, what do you think?
I believe that allowing TX csum support without SG _is_
useful even though it is not _effective_.
It is quite desirable for a driver author to be able to
test out his TX csum offload support first, then add
SG support next. Similarly, if a driver author suspects
some issues with either SG or TX csum support, he can
better isolate the problem if we allow this.
Jeff do you agree?
next prev parent reply other threads:[~2004-10-27 0:55 UTC|newest]
Thread overview: 10+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <OF96546AB5.ACE12043-ONC1256F33.0027BC6B-C1256F33.002D4A6E@de.ibm.com>
[not found] ` <E1CKE5P-0005SP-00@gondolin.me.apana.org.au>
[not found] ` <20041020163510.6d13e9c7.davem@davemloft.net>
2004-10-26 11:19 ` [PATCH] select appropriate skb size in tcp_sendmsg when TSO is used Herbert Xu
2004-10-26 23:51 ` Herbert Xu
2004-10-26 23:54 ` Jeff Garzik
2004-10-27 0:07 ` Herbert Xu
2004-10-27 0:03 ` David S. Miller
2004-10-27 1:41 ` Herbert Xu
2004-10-27 0:15 ` Jeff Garzik
2004-10-27 0:22 ` Herbert Xu
2004-10-27 0:55 ` David S. Miller [this message]
2004-10-28 4:16 ` Jeff Garzik
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=20041026175553.55a1b72d.davem@davemloft.net \
--to=davem@davemloft.net \
--cc=herbert@gondor.apana.org.au \
--cc=jgarzik@pobox.com \
--cc=netdev@oss.sgi.com \
--cc=thomas.spatzier@de.ibm.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).