Hi Alexis,
On Mon, 09 Sep 2024 22:02:07 +0200
Alexis Lothoré (eBPF Foundation) <alexis.lothore@xxxxxxxxxxx> wrote:
> test_xdp_features.sh is a shell script allowing to test that xdp features
> advertised by an interface are indeed delivered. The test works by starting
> two instance of the same program, both attaching specific xdp programs to
> each side of a veth link, and then make those programs manage packets and
> collect stats to check whether tested XDP feature is indeed delivered or
> not. However this test is not integrated in test_progs framework and so can
> not run automatically in CI.
>
> Rewrite test_xdp_features to integrate it in test_progs so it can run
> automatically in CI. The main changes brought by the rewrite are the
> following:
> - instead of running to separated processes (each one managing either the
> tester veth or the DUT vet), run a single process
> - slightly change testing direction (v0 is the tester in local namespace,
> v1 is the Device Under Test in remote namespace)
> - group all tests previously managed by test_xdp_features as subtests (one
> per tested XDP feature). As a consequence, run only once some steps
> instead of once per subtest (eg: starting/stopping the udp server). On
> the contrary, make sure that each subtest properly cleans up its state
> (ie detach xdp programs, reset test stats, etc)
> - since there is now a single process, get rid of the "control" tcp channel
> used to configure DUT. Configuring the DUT now only consists in switching
> to DUT network namespace and run the relevant commands
> - since there is no more control channel, get rid of TLVs, keep only the
> CMD_ECHO packet type, and set it as a magic
> - simplify network setup: use only ipv6 instead of both ipv4 and ipv6,
> force static neighbours instead of waiting for autoconfiguration, do not
> force gro (fetch xdp features only once xdp programs are loaded instead)
>
> The existing XDP programs are reused, with some minor changes:
> - tester and dut stats maps are converted to global variables for easier
> usage
> - programs do not use TLV struct anymore but the magic replacing the echo
> command
> - avoid to accidentally make tests pass: drop packets instead of forwarding
> them to userspace when they do not match the expected payload
>
> Signed-off-by: Alexis Lothoré (eBPF Foundation) <alexis.lothore@xxxxxxxxxxx>
I'm far for having reviewed the whole patch, but I do have one comment
below :)
[...]
> +static void *run_dut_echo_thread(void *arg)
> +{
> + struct test_data *t = (struct test_data *)arg;
> + __u32 magic;
> +
> + while (!t->quit_dut_echo_thread) {
> + struct sockaddr_storage addr;
> + socklen_t addrlen;
> + size_t n;
> +
> + n = recvfrom(t->echo_server_sock, &magic, sizeof(magic),
> + MSG_WAITALL, (struct sockaddr *)&addr, &addrlen);
> + if (n != sizeof(magic)) {
> + usleep(LOOP_DELAY_US);
> + continue;
> + }
> +
> + if (htonl(magic) != CMD_ECHO)
> + continue;
Shouldn't it be ntohl here ? The former code used the ntohs helper for
that command, and you're sending the magic in send_echo_msg with a
htonl() so I guess here you might want to convert the value back to
host endianness.
Thanks,
Maxime
