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From: Rusty Russell <rusty@rustcorp.com.au>
To: "Michael S. Tsirkin" <mst@redhat.com>
Subject: Re: [PATCHv4 2/2] vhost_net: a kernel-level virtio server
Date: Thu, 27 Aug 2009 19:29:22 +0930
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On Thu, 27 Aug 2009 02:26:55 am Michael S. Tsirkin wrote:
> On Tue, Aug 25, 2009 at 04:16:34PM +0300, Michael S. Tsirkin wrote:
> > > > +	/* If they don't want an interrupt, don't send one, unless empty. */
> > > > +	if ((flags & VRING_AVAIL_F_NO_INTERRUPT) && vq->inflight)
> > > > +		return;
> > > 
> > > And I wouldn't support notify on empty at all, TBH.
> > 
> > If I don't, virtio net in guest uses a timer, which might be expensive.
> > Will need to check what this does.
> > 
> > >  It should
> > > definitely be conditional on the guest accepting the NOTIFY_ON_EMPTY
> > > feature.
> 
> lguest does not do it this way though, do it?

Does when a patch in my current queue is applied though.

Thanks,
Rusty.