From mboxrd@z Thu Jan  1 00:00:00 1970
From: Yuanhan Liu <yuanhan.liu@linux.intel.com>
Subject: Re: [PATCH v7 4/8] vhost: rxtx: use queue id instead of
 constant ring index
Date: Thu, 22 Oct 2015 17:49:55 +0800
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To: "Michael S. Tsirkin" <mst@redhat.com>
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On Wed, Oct 21, 2015 at 05:26:18PM +0300, Michael S. Tsirkin wrote:
> On Wed, Oct 21, 2015 at 08:48:15PM +0800, Yuanhan Liu wrote:
> > > Please note that for virtio devices, guest is supposed to
> > > control the placement of incoming packets in RX queues.
> > 
> > I may not follow you.
> > 
> > Enqueuing packets to a RX queue is done at vhost lib, outside the
> > guest, how could the guest take the control here?
> > 
> > 	--yliu
> 
> vhost should do what guest told it to.
> 
> See virtio spec:
> 	5.1.6.5.5 Automatic receive steering in multiqueue mode

Spec says:

    After the driver transmitted a packet of a flow on transmitqX,
    the device SHOULD cause incoming packets for that flow to be
    steered to receiveqX.


Michael, I still have no idea how vhost could know the flow even
after discussion with Huawei. Could you be more specific about
this? Say, how could guest know that? And how could guest tell
vhost which RX is gonna to use?

Thanks.

	--yliu