selftests/bpf: Drop netns helpers in mptcp

New netns selftest helpers netns_new() and netns_free() has been added
in network_helpers.c, let's use them in mptcp selftests too instead of
using MPTCP's own helpers create_netns() and cleanup_netns().

Signed-off-by: Geliang Tang <[e-mail]>
Reviewed-by: Matthieu Baerts (NGI0) <[e-mail]>
Link: https://lore.kernel.org/r/c02[e-mail]
Signed-off-by: Martin KaFai Lau <[e-mail]>

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

···
 	char ca_name[TCP_CA_NAME_MAX];
 };
 
-static struct nstoken *create_netns(void)
-{
-	SYS(fail, "ip netns add %s", NS_TEST);
-	SYS(fail, "ip -net %s link set dev lo up", NS_TEST);
-
-	return open_netns(NS_TEST);
-fail:
-	return NULL;
-}
-
-static void cleanup_netns(struct nstoken *nstoken)
-{
-	if (nstoken)
-		close_netns(nstoken);
-
-	SYS_NOFAIL("ip netns del %s", NS_TEST);
-}
-
 static int start_mptcp_server(int family, const char *addr_str, __u16 port,
 			      int timeout_ms)
 {
···
 
 static void test_base(void)
 {
-	struct nstoken *nstoken = NULL;
+	struct netns_obj *netns = NULL;
 	int server_fd, cgroup_fd;
 
 	cgroup_fd = test__join_cgroup("/mptcp");
 	if (!ASSERT_GE(cgroup_fd, 0, "test__join_cgroup"))
 		return;
 
-	nstoken = create_netns();
-	if (!ASSERT_OK_PTR(nstoken, "create_netns"))
+	netns = netns_new(NS_TEST, true);
+	if (!ASSERT_OK_PTR(netns, "netns_new"))
 		goto fail;
 
 	/* without MPTCP */
···
 	close(server_fd);
 
 fail:
-	cleanup_netns(nstoken);
+	netns_free(netns);
 	close(cgroup_fd);
 }
 
···
 
 static void test_mptcpify(void)
 {
-	struct nstoken *nstoken = NULL;
+	struct netns_obj *netns = NULL;
 	int cgroup_fd;
 
 	cgroup_fd = test__join_cgroup("/mptcpify");
 	if (!ASSERT_GE(cgroup_fd, 0, "test__join_cgroup"))
 		return;
 
-	nstoken = create_netns();
-	if (!ASSERT_OK_PTR(nstoken, "create_netns"))
+	netns = netns_new(NS_TEST, true);
+	if (!ASSERT_OK_PTR(netns, "netns_new"))
 		goto fail;
 
 	ASSERT_OK(run_mptcpify(cgroup_fd), "run_mptcpify");
 
 fail:
-	cleanup_netns(nstoken);
+	netns_free(netns);
 	close(cgroup_fd);
 }
 
···
 static void test_subflow(void)
 {
 	struct mptcp_subflow *skel;
-	struct nstoken *nstoken;
+	struct netns_obj *netns;
 	int cgroup_fd;
 
 	cgroup_fd = test__join_cgroup("/mptcp_subflow");
···
 	if (!ASSERT_OK_PTR(skel->links._getsockopt_subflow, "attach _getsockopt_subflow"))
 		goto skel_destroy;
 
-	nstoken = create_netns();
-	if (!ASSERT_OK_PTR(nstoken, "create_netns: mptcp_subflow"))
+	netns = netns_new(NS_TEST, true);
+	if (!ASSERT_OK_PTR(netns, "netns_new: mptcp_subflow"))
 		goto skel_destroy;
 
 	if (endpoint_init("subflow") < 0)
···
 	run_subflow();
 
 close_netns:
-	cleanup_netns(nstoken);
+	netns_free(netns);
 skel_destroy:
 	mptcp_subflow__destroy(skel);
 close_cgroup: