Squash to "selftests/bpf: Add bpf scheduler test"

Now ss_search() are only used by bpf_sched tests. It will be dropped
in next step.

Signed-off-by: Geliang Tang <tanggeliang@kylinos.cn>

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

@@ -487,9 +487,15 @@ static struct nstoken *sched_init(char *flags, char *sched)
 	return NULL;
 }
 
+static int ss_search(char *src, char *dst, char *port, char *keyword)
+{
+	return SYS_NOFAIL("ip netns exec %s ss -enita src %s dst %s %s %d | grep -q '%s'",
+			  NS_TEST, src, dst, port, PORT_1, keyword);
+}
+
 static int has_bytes_sent(char *dst)
 {
-	return _ss_search(ADDR_1, dst, "sport", "bytes_sent:");
+	return ss_search(ADDR_1, dst, "sport", "bytes_sent:");
 }
 
 static void send_data_and_verify(char *sched, bool addr1, bool addr2)