Re: [PATCH bpf-next 2/2] selftests/bpf: use start_server_str rather than start_reuseport_server in tc_tunnel

Martin KaFai Lau
2025-11-06T23:29:40Z

On 11/5/25 12:22 AM, Alexis Lothoré (eBPF Foundation) wrote:
> Now that start_server_str enforces SO_REUSEADDR, there's no need to keep
> using start_reusport_server in tc_tunnel, especially since it only uses
> one server at a time.
>
> Replace start_reuseport_server with start_server_str in tc_tunnel test.
>
> Signed-off-by: Alexis Lothoré (eBPF Foundation) <alexis.lothore@bootlin.com>
> ---
> .../selftests/bpf/prog_tests/test_tc_tunnel.c | 27 ++++++++++++----------
> 1 file changed, 15 insertions(+), 12 deletions(-)
>
> diff --git a/tools/testing/selftests/bpf/prog_tests/test_tc_tunnel.c b/tools/testing/selftests/bpf/prog_tests/test_tc_tunnel.c
> index deea90aaefad..4d29256d8714 100644
> --- a/tools/testing/selftests/bpf/prog_tests/test_tc_tunnel.c
> +++ b/tools/testing/selftests/bpf/prog_tests/test_tc_tunnel.c
> @@ -69,7 +69,7 @@ struct subtest_cfg {
> int client_egress_prog_fd;
> int server_ingress_prog_fd;
> char extra_decap_mod_args[TUNNEL_ARGS_MAX_LEN];
> - int *server_fd;
> + int server_fd;
> };
>
> struct connection {
> @@ -135,16 +135,18 @@ static int run_server(struct subtest_cfg *cfg)
> {
> int family = cfg->ipproto == 6 ? AF_INET6 : AF_INET;
> struct nstoken *nstoken;
> + struct network_helper_opts opts = {
> + .timeout_ms = TIMEOUT_MS
> + };
>
> nstoken = open_netns(SERVER_NS);
> if (!ASSERT_OK_PTR(nstoken, "open server ns"))
> return -1;
>
> - cfg->server_fd = start_reuseport_server(family, SOCK_STREAM,
> - cfg->server_addr, TEST_PORT,
> - TIMEOUT_MS, 1);
> + cfg->server_fd = start_server_str(family, SOCK_STREAM, cfg->server_addr,
> + TEST_PORT, &opts);
> close_netns(nstoken);
> - if (!ASSERT_OK_PTR(cfg->server_fd, "start server"))
> + if (!ASSERT_OK_FD(cfg->server_fd, "start server"))
> return -1;
>
> return 0;
> @@ -152,7 +154,7 @@ static int run_server(struct subtest_cfg *cfg)
>
> static void stop_server(struct subtest_cfg *cfg)
> {
> - free_fds(cfg->server_fd, 1);
> + close(cfg->server_fd);
> }
>
> static int check_server_rx_data(struct subtest_cfg *cfg,
> @@ -188,7 +190,7 @@ static struct connection *connect_client_to_server(struct subtest_cfg *cfg)
> return NULL;
> }
>
> - server_fd = accept(*cfg->server_fd, NULL, NULL);
> + server_fd = accept(cfg->server_fd, NULL, NULL);
> if (server_fd < 0) {
> close(client_fd);
> free(conn);
> @@ -394,29 +396,30 @@ static void run_test(struct subtest_cfg *cfg)
>
> /* Basic communication must work */
> if (!ASSERT_OK(send_and_test_data(cfg, true), "connect without any encap"))
> - goto fail;
> + goto fail_close_server;
>
> /* Attach encapsulation program to client */
> if (!ASSERT_OK(configure_encapsulation(cfg), "configure encapsulation"))
> - goto fail;
> + goto fail_close_server;
>
> /* If supported, insert kernel decap module, connection must succeed */
> if (!cfg->expect_kern_decap_failure) {
> if (!ASSERT_OK(configure_kernel_decapsulation(cfg),
> "configure kernel decapsulation"))
> - goto fail;
> + goto fail_close_server;
> if (!ASSERT_OK(send_and_test_data(cfg, true),
> "connect with encap prog and kern decap"))
> - goto fail;
> + goto fail_close_server;
> }
>
> /* Replace kernel decapsulation with BPF decapsulation, test must pass */
> if (!ASSERT_OK(configure_ebpf_decapsulation(cfg), "configure ebpf decapsulation"))
> - goto fail;
> + goto fail_close_server;
> ASSERT_OK(send_and_test_data(cfg, true), "connect with encap and decap progs");
>
> fail:
> stop_server(cfg);
> +fail_close_server:

The "fail" and "fail_close_server" ordering is incorrect. I took this
chance to simplify it by doing run_server() before open_netns().

Applied. Thanks.
> close_netns(nstoken);
> }
>
>