From: "Michael S. Tsirkin" <mst@redhat.com>
To: Anthony Liguori <anthony@codemonkey.ws>
Cc: Arnd Bergmann <arnd@arndb.de>,
virtualization@lists.linux-foundation.org,
"Ira W. Snyder" <iws@ovro.caltech.edu>,
netdev@vger.kernel.org, kvm@vger.kernel.org,
linux-kernel@vger.kernel.org
Subject: Re: [PATCH 2/2] vhost_net: a kernel-level virtio server
Date: Thu, 13 Aug 2009 09:31:13 +0300 [thread overview]
Message-ID: <20090813063113.GA3508@redhat.com> (raw)
In-Reply-To: <4A8317A3.4030303@codemonkey.ws>
On Wed, Aug 12, 2009 at 02:27:31PM -0500, Anthony Liguori wrote:
> Arnd Bergmann wrote:
>>> As I pointed out earlier, most code in virtio net is asymmetrical: guest
>>> provides buffers, host consumes them. Possibly, one could use virtio
>>> rings in a symmetrical way, but support of existing guest virtio net
>>> means there's almost no shared code.
>>>
>>
>> The trick is to swap the virtqueues instead. virtio-net is actually
>> mostly symmetric in just the same way that the physical wires on a
>> twisted pair ethernet are symmetric (I like how that analogy fits).
>>
>
> It's already been done between two guests. See
> http://article.gmane.org/gmane.linux.kernel.virtualization/5423
>
> Regards,
>
> Anthony Liguori
Yes, this works by copying data (see PATCH 5/5). Another possibility is
page flipping. Either will kill performance.
--
MST
next prev parent reply other threads:[~2009-08-13 6:32 UTC|newest]
Thread overview: 65+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <cover.1249930169.git.mst@redhat.com>
2009-08-10 18:53 ` [PATCH 1/2] export cpu_tlbstate to modules Michael S. Tsirkin
2009-08-10 18:53 ` Michael S. Tsirkin
2009-08-10 21:56 ` H. Peter Anvin
2009-08-10 21:56 ` H. Peter Anvin
2009-08-10 22:06 ` Michael S. Tsirkin
2009-08-10 22:24 ` H. Peter Anvin
2009-08-10 22:24 ` H. Peter Anvin
2009-08-11 11:19 ` Michael S. Tsirkin
2009-08-11 11:19 ` Michael S. Tsirkin
2009-08-11 11:19 ` Michael S. Tsirkin
2009-08-10 22:06 ` Michael S. Tsirkin
2009-08-10 18:53 ` [PATCH 2/2] vhost_net: a kernel-level virtio server Michael S. Tsirkin
2009-08-10 19:51 ` Arnd Bergmann
2009-08-10 19:51 ` Arnd Bergmann
2009-08-10 20:10 ` Michael S. Tsirkin
2009-08-10 20:10 ` Michael S. Tsirkin
2009-08-10 22:16 ` Arnd Bergmann
2009-08-10 22:16 ` Arnd Bergmann
2009-08-12 17:03 ` Arnd Bergmann
2009-08-12 17:03 ` Arnd Bergmann
2009-08-12 17:19 ` Ira W. Snyder
2009-08-12 17:31 ` Michael S. Tsirkin
2009-08-12 17:48 ` Ira W. Snyder
2009-08-12 17:48 ` Ira W. Snyder
2009-08-13 5:55 ` Michael S. Tsirkin
2009-08-13 5:55 ` Michael S. Tsirkin
2009-08-12 17:31 ` Michael S. Tsirkin
2009-08-12 17:19 ` Ira W. Snyder
2009-08-12 17:21 ` Michael S. Tsirkin
2009-08-12 17:59 ` Arnd Bergmann
2009-08-12 19:27 ` Anthony Liguori
2009-08-13 6:31 ` Michael S. Tsirkin
2009-08-13 6:31 ` Michael S. Tsirkin [this message]
2009-08-12 19:27 ` Anthony Liguori
2009-08-13 6:06 ` Michael S. Tsirkin
2009-08-13 6:06 ` Michael S. Tsirkin
2009-08-13 13:38 ` Arnd Bergmann
2009-08-13 13:38 ` Arnd Bergmann
2009-08-13 13:48 ` Arnd Bergmann
2009-08-13 14:41 ` Michael S. Tsirkin
2009-08-13 14:41 ` Michael S. Tsirkin
2009-08-13 14:53 ` Arnd Bergmann
2009-08-13 14:53 ` Arnd Bergmann
2009-08-13 15:37 ` Avi Kivity
2009-08-13 15:37 ` Avi Kivity
2009-08-20 7:25 ` Rusty Russell
2009-08-20 7:25 ` Rusty Russell
2009-08-13 13:48 ` Arnd Bergmann
2009-08-13 14:39 ` Michael S. Tsirkin
2009-08-13 14:58 ` Arnd Bergmann
2009-08-13 15:03 ` Michael S. Tsirkin
2009-08-13 15:03 ` Michael S. Tsirkin
2009-08-13 14:58 ` Arnd Bergmann
2009-08-13 14:39 ` Michael S. Tsirkin
2009-08-12 17:59 ` Arnd Bergmann
2009-08-12 19:22 ` Anthony Liguori
2009-08-13 8:45 ` Michael S. Tsirkin
2009-08-13 8:45 ` Michael S. Tsirkin
2009-08-13 13:45 ` Arnd Bergmann
2009-08-13 13:45 ` Arnd Bergmann
2009-08-12 19:22 ` Anthony Liguori
2009-08-12 17:21 ` Michael S. Tsirkin
2009-08-12 19:58 ` Paul E. McKenney
2009-08-12 19:58 ` Paul E. McKenney
2009-08-10 18:53 ` Michael S. Tsirkin
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