Re: [PATCH rfc 0/3] virtio-net: add tx-hash, rx-tstamp and tx-tstamp

From: "Michael S. Tsirkin" <mst@redhat.com>
To: Willem de Bruijn <willemdebruijn.kernel@gmail.com>
Cc: virtualization@lists.linux-foundation.org,
	netdev@vger.kernel.org, jasowang@redhat.com,
	Willem de Bruijn <willemb@google.com>
Subject: Re: [PATCH rfc 0/3] virtio-net: add tx-hash, rx-tstamp and tx-tstamp
Date: Mon, 28 Dec 2020 12:29:26 -0500	[thread overview]
Message-ID: <20201228122911-mutt-send-email-mst@kernel.org> (raw)
In-Reply-To: <20201228162233.2032571-1-willemdebruijn.kernel@gmail.com>

On Mon, Dec 28, 2020 at 11:22:30AM -0500, Willem de Bruijn wrote:
> From: Willem de Bruijn <willemb@google.com>
> 
> RFC for three new features to the virtio network device:
> 
> 1. pass tx flow hash and state to host, for routing + telemetry
> 2. pass rx tstamp to guest, for better RTT estimation
> 3. pass tx tstamp to host, for accurate pacing
> 
> All three would introduce an extension to the virtio spec.
> I assume this would require opening three ballots against v1.2 at
> https://www.oasis-open.org/committees/ballots.php?wg_abbrev=virtio
> 
> This RFC is to informally discuss the proposals first.
> 
> The patchset is against v5.10. Evaluation additionally requires
> changes to qemu and at least one back-end. I implemented preliminary
> support in Linux vhost-net. Both patches available through github at
> 
> https://github.com/wdebruij/linux/tree/virtio-net-txhash-1
> https://github.com/wdebruij/qemu/tree/virtio-net-txhash-1

Any data on what the benefits are?

> Willem de Bruijn (3):
>   virtio-net: support transmit hash report
>   virtio-net: support receive timestamp
>   virtio-net: support transmit timestamp
> 
>  drivers/net/virtio_net.c        | 52 +++++++++++++++++++++++++++++++--
>  include/uapi/linux/virtio_net.h | 23 ++++++++++++++-
>  2 files changed, 71 insertions(+), 4 deletions(-)
> 
> -- 
> 2.29.2.729.g45daf8777d-goog