virtio — archive

[PATCH requirements 0/7] virtio net new features requirements

From: David Edmondson <[email protected]>
To: [email protected]
Date: Mon, 14 Aug 2023 12:00:00 -0000

On Monday, 2023-07-24 at 06:34:20 +03, Parav Pandit wrote: > Add tx and rx packet timestamp requirements. > > Signed-off-by: Parav Pandit <[email protected]> Acked-by: David Edmondson <[email protected]> > --- > net-workstream/features-1.4.md 26 ++++++++++++++++++++++++++ > 1 file changed, 26 insertions(+) > > diff --git a/net-workstream/features-1.4.md b/net-workstream/features-1.4.md > index d228462..37820b6 100644 > --- a/net-workstream/features-1.4.md > +++ b/net-workstream/features-1.4.md > @@ -10,6 +10,7 @@ together is desired while updating the virtio net interface. > 2. Low latency tx and rx virtqueues for PCI transport > 3. Virtqueue notification coalescing re-arming support > 4 Virtqueue receive flow filters (RFF) > +5. Device timestamp for tx and rx packets > > # 3. Requirements > ## 3.1 Device counters > @@ -280,3 +281,28 @@ struct virtio_net_rff_delete { > u8 padding[2]; > le32 flow_id; > }; > + > +## 3.5 Packet timestamp > +1. Device should provide transmit timestamp and receive timestamp of the packets > + at per packet level when the device is enabled. > +2. Device should provide the current free running clock in the least latency > + possible using an MMIO register read of 64-bit to have the least jitter. > +3. Device should provide the current frequency and the frequency unit for the > + software to synchronize the reference point of software and the device using > + a control vq command. > + > +### 3.5.1 Transmit timestamp > +1. Transmit completion must contain a packet transmission timestamp when the > + device is enabled for it. > +2. The device should record the packet transmit timestamp in the completion at > + the farthest egress point towards the network. > +3. The device must provide a transmit packet timestamp in a single DMA > + transaction along with the rest of the transmit completion fields. > + > +### 3.5.2 Receive timestamp > +1. Receive completion must contain a packet reception timestamp when the device > + is enabled for it. > +2. The device should record the received packet timestamp at the closet ingress > + point of reception from the network. > +3. The device should provide a receive packet timestamp in a single DMA > + transaction along with the rest of the receive completion fields. -- Do not leave the building.