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

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

On Monday, 2023-07-24 at 06:34:15 +03, Parav Pandit wrote:
> Add requirements document template for the virtio net features.
>
> Add virtio net device counters visible to driver.

Minor, but perhaps separate the introduction and the statistics into
distinct changes.

> Signed-off-by: Parav Pandit <parav@nvidia.com>
> ---
> changelog:
> v0->v1:
> - removed tx dropped counter
> - updated requirements to mention about virtqueue interface for counters
>   query
> ---
>  net-workstream/features-1.4.md | 35 ++++++++++++++++++++++++++++++++++
>  1 file changed, 35 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..4c3797b
> --- /dev/null
> +++ b/net-workstream/features-1.4.md
> @@ -0,0 +1,35 @@
> +# 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.

Isn't this really "if the driver is migrated"?

I'm not sure of an obvious term for "the abstracted device that
represents an actual device to which this driver is attached".

> +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.

Suggest:

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.

> +
> +### 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_gro_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

The patch from Xuan includes more than this - perhaps include them here
so that we can debate the specifics?
-- 
Walking upside down in the sky, between the satellites passing by, I'm looking.