Re: [PATCH trivial] tcp_vu, udp_vu: Fix comment headers for header length functions

[Stefano Brivio <sbrivio@redhat.com>]

On Tue, 24 Feb 2026 13:22:27 +0100
Laurent Vivier <lvivier@redhat.com> wrote:

> The comment headers for tcp_vu_hdrlen() and udp_vu_hdrlen() described
> the return value as "the size of the header in level 2 frame", but
> these functions also include the virtio net header, which is not part
> of the L2 frame.
> 
> Signed-off-by: Laurent Vivier <lvivier@redhat.com>
> ---
>  tcp_vu.c | 4 ++--
>  udp_vu.c | 4 ++--
>  2 files changed, 4 insertions(+), 4 deletions(-)
> 
> diff --git a/tcp_vu.c b/tcp_vu.c
> index 94169c21f700..8908d376a7dd 100644
> --- a/tcp_vu.c
> +++ b/tcp_vu.c
> @@ -40,10 +40,10 @@ static struct vu_virtq_element elem[VIRTQUEUE_MAX_SIZE];
>  static int head[VIRTQUEUE_MAX_SIZE + 1];
>  
>  /**
> - * tcp_vu_hdrlen() - return the size of the header in level 2 frame (TCP)
> + * tcp_vu_hdrlen() - Return the size of virtio net and L2 headers (TCP)

Thanks, I think that this, plus the line changed below, makes it clear.

What I still find confusing is: "L2 headers (TCP)". If I see this
together with udp_vu_hdrlen() I understand what you mean, but
otherwise I'd ask myself what TCP has to do with Layer-2...

I tried rephrasing it a bit, what do you think about:

 * tcp_vu_hdrlen() - Sum size of all headers, from TCP to virtio-net

>   * @v6:		Set for IPv6 packet
>   *
> - * Return: return the size of the header
> + * Return: total size of virtio net header, Ethernet, IP and TCP headers

...and changing this to "virtio-net" (not a very official name but it
seems to be widely used, more than "virtio net"...)?

If you're fine with it (same for UDP) I would change it and apply. I'm
not exactly proud of this either, so if you or somebody else has better
ideas...

>   */
>  static size_t tcp_vu_hdrlen(bool v6)
>  {
> diff --git a/udp_vu.c b/udp_vu.c
> index d190fef82d49..dd3f8e9272ff 100644
> --- a/udp_vu.c
> +++ b/udp_vu.c
> @@ -37,10 +37,10 @@ static struct iovec     iov_vu		[VIRTQUEUE_MAX_SIZE];
>  static struct vu_virtq_element	elem		[VIRTQUEUE_MAX_SIZE];
>  
>  /**
> - * udp_vu_hdrlen() - return the size of the header in level 2 frame (UDP)
> + * udp_vu_hdrlen() - Return the size of virtio net and L2 headers (UDP)
>   * @v6:		Set for IPv6 packet
>   *
> - * Return: return the size of the header
> + * Return: total size of virtio net header, Ethernet, IP and UDP headers
>   */
>  static size_t udp_vu_hdrlen(bool v6)
>  {

-- 
Stefano