Re: [PATCH 0/3] Rename queue index to queue number

[Cornelia Huck <cohuck@redhat.com>]

On Thu, Feb 23 2023, Parav Pandit <parav@nvidia.com> wrote:

> 1. Currently, virtqueue is identified between driver and device
> interchangeably using either number of index terminology.
>
> 2. Between PCI and MMIO transport the queue size (depth) is
> defined as queue_size and QueueNum respectively.
>
> To avoid confusion and to have consistency, unify them to use as Number.
>
> Solution:
> Use virtqueue number description, and rename MMIO register as QueueSize.
>
> Patch summary:
> patch-1 renames index to number for pci transport
> patch-2 renames mmio register from Num to Size
> patch-3 renames index to number for mmio transport
>
> Please review.
> This series fixes the issue [1].
>
> This series is on top of [2].
>
> [1] https://github.com/oasis-tcs/virtio-spec/issues/163
> [2] https://lists.oasis-open.org/archives/virtio-dev/202302/msg00527.html
>
> ---
> Cornelia:
> I was not sure about ccw for vq_config_block and vq_info_block structures
> index field refers to the queue number or not.
> Can you please clarify?
>
> If it vqn, I will send v1 by replacing index to vqn to be
> consistent with other part of the spec which also uses vqn.

The vq_*_block structures use "index" for the vq index/number and "num"
for the number of buffers (queue size).

I'm wondering what terminology we should standardize on. For the size of
the queue, we have queue_size, QueueNum, and num. Calling it some
variation of "queue size" and mentioning that it refers to the number of
buffers makes sense.

For the vq index/number, I'm not that sure that "virtqueue number" is
better that "virtqueue index" -- actually, I'd prefer the latter. We'd
need some renaming either way.