From 4cd729fa022cb5142e5b65f25589af61c8148cf6 Mon Sep 17 00:00:00 2001 From: Andrii Nakryiko Date: Wed, 11 Mar 2020 15:27:49 -0700 Subject: selftests/bpf: Make tcp_rtt test more robust to failures Switch to non-blocking accept and wait for server thread to exit before proceeding. I noticed that sometimes tcp_rtt server thread failure would "spill over" into other tests (that would run after tcp_rtt), probably just because server thread exits much later and tcp_rtt doesn't wait for it. v1->v2: - add usleep() while waiting on initial non-blocking accept() (Stanislav); Fixes: 8a03222f508b ("selftests/bpf: test_progs: fix client/server race in tcp_rtt") Signed-off-by: Andrii Nakryiko Signed-off-by: Alexei Starovoitov Reviewed-by: Stanislav Fomichev Link: https://lore.kernel.org/bpf/20200311222749.458015-1-andriin@fb.com Signed-off-by: Alexei Starovoitov --- tools/testing/selftests/bpf/prog_tests/tcp_rtt.c | 32 +++++++++++++++--------- 1 file changed, 20 insertions(+), 12 deletions(-) (limited to 'tools/testing/selftests/bpf/prog_tests/tcp_rtt.c') diff --git a/tools/testing/selftests/bpf/prog_tests/tcp_rtt.c b/tools/testing/selftests/bpf/prog_tests/tcp_rtt.c index f4cd60d6fba2..e08f6bb17700 100644 --- a/tools/testing/selftests/bpf/prog_tests/tcp_rtt.c +++ b/tools/testing/selftests/bpf/prog_tests/tcp_rtt.c @@ -188,7 +188,7 @@ static int start_server(void) }; int fd; - fd = socket(AF_INET, SOCK_STREAM, 0); + fd = socket(AF_INET, SOCK_STREAM | SOCK_NONBLOCK, 0); if (fd < 0) { log_err("Failed to create server socket"); return -1; @@ -205,6 +205,7 @@ static int start_server(void) static pthread_mutex_t server_started_mtx = PTHREAD_MUTEX_INITIALIZER; static pthread_cond_t server_started = PTHREAD_COND_INITIALIZER; +static volatile bool server_done = false; static void *server_thread(void *arg) { @@ -222,23 +223,24 @@ static void *server_thread(void *arg) if (CHECK_FAIL(err < 0)) { perror("Failed to listed on socket"); - return NULL; + return ERR_PTR(err); } - client_fd = accept(fd, (struct sockaddr *)&addr, &len); + while (!server_done) { + client_fd = accept(fd, (struct sockaddr *)&addr, &len); + if (client_fd == -1 && errno == EAGAIN) { + usleep(50); + continue; + } + break; + } if (CHECK_FAIL(client_fd < 0)) { perror("Failed to accept client"); - return NULL; + return ERR_PTR(err); } - /* Wait for the next connection (that never arrives) - * to keep this thread alive to prevent calling - * close() on client_fd. - */ - if (CHECK_FAIL(accept(fd, (struct sockaddr *)&addr, &len) >= 0)) { - perror("Unexpected success in second accept"); - return NULL; - } + while (!server_done) + usleep(50); close(client_fd); @@ -249,6 +251,7 @@ void test_tcp_rtt(void) { int server_fd, cgroup_fd; pthread_t tid; + void *server_res; cgroup_fd = test__join_cgroup("/tcp_rtt"); if (CHECK_FAIL(cgroup_fd < 0)) @@ -267,6 +270,11 @@ void test_tcp_rtt(void) pthread_mutex_unlock(&server_started_mtx); CHECK_FAIL(run_test(cgroup_fd, server_fd)); + + server_done = true; + pthread_join(tid, &server_res); + CHECK_FAIL(IS_ERR(server_res)); + close_server_fd: close(server_fd); close_cgroup_fd: -- cgit