netdev - Re: poor network loopback performance and scalability

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <20080421.011623.67335122.davem@davemloft.net>
Date:	Mon, 21 Apr 2008 01:16:23 -0700 (PDT)
From:	David Miller <davem@...emloft.net>
To:	mingo@...e.hu
Cc:	herbert@...dor.apana.org.au, dada1@...mosbay.com,
	netdev@...r.kernel.org, linux-kernel@...r.kernel.org,
	a.p.zijlstra@...llo.nl
Subject: Re: poor network loopback performance and scalability

From: Ingo Molnar <mingo@...e.hu>
Date: Mon, 21 Apr 2008 10:11:03 +0200

> 
> * David Miller <davem@...emloft.net> wrote:
> 
> > To move things forward, we should look into doing something similar to 
> > what Al Viro suggested, which would be to return an SKB pointer from 
> > the transmit path and call back into netif_receive_skb() using that.
> 
> yep, basically the sk_peer trick that AF_UNIX is already using.

Please read again, that isn't the suggestion being discussed.

What's being discussed is having the top of the transmit call path
getting a socket "buffer" pointer, that it can feed back into the
packet input path directly.  Loopback would return buffer pointers
from ->hard_start_xmit() instead of passing them netif_rx().  The top
of the transmit call path, upon getting a non-NULL buffer returned,
would pass it to netif_receive_skb().

We're not talking about sockets, although that is another idea (which
I'm working on a patch for, and I have a mechanism for what you refer
to as "path validation").
--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html