Re: [PATCH v5 bpf-next 8/8] selftests/bpf: introduce XDP compliance test tool

[Alexei Starovoitov <alexei.starovoitov@gmail.com>]

On Wed, Feb 1, 2023 at 2:25 AM Lorenzo Bianconi <lorenzo@kernel.org> wrote:
>
> Introduce xdp_features tool in order to test XDP features supported by
> the NIC and match them against advertised ones.
> In order to test supported/advertised XDP features, xdp_features must
> run on the Device Under Test (DUT) and on a Tester device.
> xdp_features opens a control TCP channel between DUT and Tester devices
> to send control commands from Tester to the DUT and a UDP data channel
> where the Tester sends UDP 'echo' packets and the DUT is expected to
> reply back with the same packet. DUT installs multiple XDP programs on the
> NIC to test XDP capabilities and reports back to the Tester some XDP stats.


'DUT installs...'? what? The device installs XDP programs ?

> +
> +       ctrl_sockfd = accept(*sockfd, (struct sockaddr *)&ctrl_addr, &addrlen);
> +       if (ctrl_sockfd < 0) {
> +               fprintf(stderr, "Failed to accept connection on DUT socket\n");

Applied, but overuse of the word 'DUT' is incorrect and confusing.

'DUT socket' ? what is that?
'Invalid DUT address' ? what address?
The UX in general is not user friendly.

./xdp_features
Invalid ifindex

This is not a helpful message.

./xdp_features eth0
Starting DUT on device 3
Failed to accept connection on DUT socket

'Starting DUT' ? What did it start?