Re: [virtio-comment] [PATCH requirements v4 1/7] net-features: Add requirements document for release 1.4

[David Edmondson <david.edmondson@oracle.com>]

On Tuesday, 2023-08-15 at 10:45:54 +03, Parav Pandit wrote:
> Add requirements document template for the virtio net features.
>
> Add virtio net device counters visible to driver.
>
> Signed-off-by: Parav Pandit <parav@nvidia.com>
> ---
> changelog:
> v3->v4:
> - Addressed comment from David
> - Added link to more counters that we are already discussing
> v0->v1:
> - removed tx dropped counter
> - updated requirements to mention about virtqueue interface for counters
>   query
> ---
>  net-workstream/features-1.4.md | 43 ++++++++++++++++++++++++++++++++++
>  1 file changed, 43 insertions(+)
>  create mode 100644 net-workstream/features-1.4.md
>
> diff --git a/net-workstream/features-1.4.md b/net-workstream/features-1.4.md
> new file mode 100644
> index 0000000..c2b1cc8
> --- /dev/null
> +++ b/net-workstream/features-1.4.md
> @@ -0,0 +1,43 @@
> +# 1. Introduction
> +
> +This document describes the overall requirements for virtio net device
> +improvements for upcoming release 1.4. Some of these requirements are
> +interrelated and influence the interface design, hence reviewing them
> +together is desired while updating the virtio net interface.
> +
> +# 2. Summary
> +1. Device counters visible to the driver
> +
> +# 3. Requirements
> +## 3.1 Device counters
> +1. The driver should be able to query the device and/or per vq counters for
> +   debugging purpose using a virtqueue directly from driver to device for
> +   example using a control vq.
> +2. The driver should be able to query which counters are supported using a
> +   virtqueue command, for example using an existing control vq.
> +3. If this device is migrated between two hosts, the driver should be able
> +   get the counter values in the destination host from where it was left
> +   off in the source host.
> +4. If a virtio device is group member device, a group owner should be able
> +   to query all the counter attributes using the administration command which
> +   a virtio member device will expose via a virtqueue to the driver.

The language seems confusing here. How about:

If a virtio device is a group member device, it must be possible to
query all of the group member counter attributes via the group owner
device.

> +4. If a virtio device is a group member device, a group owner should be able
> +   to query all of the member device counter attributes and counters via the
> +   group owner device.

Similarly:

If a virtio device is a group member device, it must be possible to
query all of the group member counters via the group owner device.

> +
> +### 3.1.1 Per receive queue counters
> +1. le64 rx_oversize_pkt_errors: Packet dropped due to receive packet being
> +    oversize than the buffer size
> +2. le64 rx_no_buffer_pkt_errors: Packet dropped due to unavailability of the
> +    buffer in the receive queue
> +3. le64 rx_gso_pkts: Packets treated as receive GSO sequence by the device
> +4. le64 rx_pkts: Total packets received by the device
> +
> +### 3.1.2 Per transmit queue counters
> +1. le64 tx_gso_pkts: Packets send as transmit GSO sequence
> +2. le64 tx_pkts: Total packets send by the device
> +
> +### 3.1.3 More counters
> +More counters discussed in [1].
> +
> +[1] https://lists.oasis-open.org/archives/virtio-comment/202308/msg00176.html
-- 
It's gettin', it's gettin', it's gettin' kinda hectic.