netdev.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Vlad Yasevich <vyasevic@redhat.com>
To: Eric Dumazet <eric.dumazet@gmail.com>
Cc: netdev@vger.kernel.org, davem@davemloft.net
Subject: Re: [PATCHv3] ipv6: Enable enough of the code to handle GSO when disabled.
Date: Wed, 17 Oct 2012 15:11:45 -0400	[thread overview]
Message-ID: <507F02F1.5010501@redhat.com> (raw)
In-Reply-To: <1350490397.26103.647.camel@edumazet-glaptop>

On 10/17/2012 12:13 PM, Eric Dumazet wrote:
> On Wed, 2012-10-17 at 11:46 -0400, Vlad Yasevich wrote:
>
>> This patch attempts to solve this by enabling just enough code so GSO
>> is correctly processed.  However, I should point out that if IPv6 is
>> simply blacklisted or not built for the kernel, this problem will
>> still persist.
>
> So I guess this should be done in a different way ?
>
> We currently use a single structure (struct packet_type) to hold
> pointers to different methods. (The .func() field, and the gso/gro
> stuff)
>
> We probably need to split it in two parts, and make one part linked into
> kernel, even if CONFIG_IPV6=n, so that GRO/GSO is fully IPv4/IPv6
> functional.

The thing about this approach is that if there are any other protocols 
that could have to provide their own segmentation functionality, such 
functionality would always have to be part of the kernel.  I wasn't sure 
how much I liked that.

>
> By the way, do we really need a hash table for this ?
> It seems we only have IPv4 (ETH_P_IP) and IPv6 (ETH_P_IPV6) to take care
> of ?

Which hash are you talking about?  I didn't add any hashes.

>
> This would remove some tests we currently have in GRO stack, and some
> RCU stuff as well.
> (GRO is slower if we have many af_packet sockets)
>
> list_for_each_entry_rcu(ptype, head, list) {
>      if (ptype->type != type || ptype->dev || !ptype->gro_receive)
>          continue;
> ...
>
> Adding a hook/test in ipv6_rcv() is ugly.
>

There already is one for device.  I original had a stub ipv6_rcv that 
just dropped the packet.  I could resurrect that if that's better...

-vlad

>
>
> --
> To unsubscribe from this list: send the line "unsubscribe netdev" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html
>

  parent reply	other threads:[~2012-10-17 19:11 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2012-10-17 15:46 [PATCHv3] ipv6: Enable enough of the code to handle GSO when disabled Vlad Yasevich
2012-10-17 16:13 ` Eric Dumazet
2012-10-17 16:50   ` Ben Hutchings
2012-10-17 19:03     ` Vlad Yasevich
2012-10-17 19:11   ` Vlad Yasevich [this message]
2012-10-17 19:33     ` Eric Dumazet

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=507F02F1.5010501@redhat.com \
    --to=vyasevic@redhat.com \
    --cc=davem@davemloft.net \
    --cc=eric.dumazet@gmail.com \
    --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).