Re: [Xen-devel] [PATCH RFC 1/3] virtio infrastructure

[Rusty Russell <rusty-8n+1lVoiYb80n/F98K4Iww@public.gmane.org>]

On Tue, 2007-06-05 at 02:05 +0000, Santos, Jose Renato G wrote:

> > From: Jeremy Fitzhardinge [mailto:jeremy-TSDbQ3PG+2Y@public.gmane.org] 
> > The hope is that the Xen-specific elements of the driver will 
> > be restricted to Xen-specific things like grant tables, and 
> > the bulk of the driver and its logic can be common.  Whether 
> > that can be achieved and still retain the full 
> > performance/features of the entirely Xen-specific netfront 
> > driver remains to be seen.  I haven't had a chance to look at 
> > doing any Xen-virtio glue yet, so I'm not really sure how it 
> > will work out.
> > 
> >     J
> > 
> 
>   Ok, if you share some common code this could be beneficial, but
>   in the specific case of Xen networking I believe most of netfront
>   code is Xen specific.  I think that a generic "virtual-IO" layer 
>   would not be beneficial in this case, but instead it would 
>   only add extra complexity to glue the layers.

This is precisely the plan: to code it up and look hard at it.  If
performance gets hurt, it's a lose.  If performance is equal and the
code is clearer, it's a win, and this is my goal.

Perhaps you underestimate how much of the Xen netfront driver is
actually dealing with things which *any* efficient virtio I/O netdriver
will have to wrestle with.

Thanks!
Rusty.


-------------------------------------------------------------------------
This SF.net email is sponsored by DB2 Express
Download DB2 Express C - the FREE version of DB2 express and take
control of your XML. No limits. Just data. Click to get it now.
http://sourceforge.net/powerbar/db2/