selftests/bpf: Convert tcp_rtt test to ASSERT_* macros

Convert the selftest to use the preferred ASSERT_* macros instead of the
deprecated CHECK().
Signed-off-by: Wang Yufen <wangyufen@huawei.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/1664169131-32405-10-git-send-email-wangyufen@huawei.com

tools/testing/selftests/bpf/prog_tests/tcp_rtt.c

@@ -16,8 +16,7 @@ static void send_byte(int fd)
 {
 	char b = 0x55;
 
-	if (CHECK_FAIL(write(fd, &b, sizeof(b)) != 1))
-		perror("Failed to send single byte");
+	ASSERT_EQ(write(fd, &b, sizeof(b)), 1, "send single byte");
 }
 
 static int wait_for_ack(int fd, int retries)
@@ -51,10 +50,8 @@ static int verify_sk(int map_fd, int client_fd, const char *msg, __u32 invoked,
 	int err = 0;
 	struct tcp_rtt_storage val;
 
-	if (CHECK_FAIL(bpf_map_lookup_elem(map_fd, &client_fd, &val) < 0)) {
-		perror("Failed to read socket storage");
+	if (!ASSERT_GE(bpf_map_lookup_elem(map_fd, &client_fd, &val), 0, "read socket storage"))
 		return -1;
-	}
 
 	if (val.invoked != invoked) {
 		log_err("%s: unexpected bpf_tcp_sock.invoked %d != %d",
@@ -151,14 +148,14 @@ void test_tcp_rtt(void)
 	int server_fd, cgroup_fd;
 
 	cgroup_fd = test__join_cgroup("/tcp_rtt");
-	if (CHECK_FAIL(cgroup_fd < 0))
+	if (!ASSERT_GE(cgroup_fd, 0, "join_cgroup /tcp_rtt"))
 		return;
 
 	server_fd = start_server(AF_INET, SOCK_STREAM, NULL, 0, 0);
-	if (CHECK_FAIL(server_fd < 0))
+	if (!ASSERT_GE(server_fd, 0, "start_server"))
 		goto close_cgroup_fd;
 
-	CHECK_FAIL(run_test(cgroup_fd, server_fd));
+	ASSERT_OK(run_test(cgroup_fd, server_fd), "run_test");
 
 	close(server_fd);