From: Geliang Tang <tanggeliang@kylinos.cn>

The newly added helper create_netns() can be used in assign_reuse.c,
fib_lookup.c, ns_current_pid_tgid.c, sock_destroy.c and sock_iter_batch.c
to simplify the code.

It changes the behavior of test fib_lookup.c a little bit, but doesn't
affect the results.

Signed-off-by: Geliang Tang <tanggeliang@kylinos.cn>
---
 tools/testing/selftests/bpf/prog_tests/assign_reuse.c    | 9 ++-------
 tools/testing/selftests/bpf/prog_tests/fib_lookup.c      | 4 +---
 .../selftests/bpf/prog_tests/ns_current_pid_tgid.c       | 5 +----
 tools/testing/selftests/bpf/prog_tests/sock_destroy.c    | 5 +----
 tools/testing/selftests/bpf/prog_tests/sock_iter_batch.c | 6 +-----
 5 files changed, 6 insertions(+), 23 deletions(-)

diff --git a/tools/testing/selftests/bpf/prog_tests/assign_reuse.c b/tools/testing/selftests/bpf/prog_tests/assign_reuse.c
index 989ee4d9785b..21e1549d9749 100644
--- a/tools/testing/selftests/bpf/prog_tests/assign_reuse.c
+++ b/tools/testing/selftests/bpf/prog_tests/assign_reuse.c
@@ -175,12 +175,9 @@ void test_assign_reuse(void)
 {
 	struct nstoken *tok = NULL;
 
-	SYS(out, "ip netns add %s", NS_TEST);
-	SYS(cleanup, "ip -net %s link set dev lo up", NS_TEST);
-
-	tok = open_netns(NS_TEST);
+	tok = create_netns(NS_TEST);
 	if (!ASSERT_OK_PTR(tok, "netns token"))
-		return;
+		goto cleanup;
 
 	if (test__start_subtest("tcpv4"))
 		run_assign_reuse(AF_INET, SOCK_STREAM, "127.0.0.1", PORT);
@@ -194,6 +191,4 @@ void test_assign_reuse(void)
 cleanup:
 	close_netns(tok);
 	SYS_NOFAIL("ip netns delete %s", NS_TEST);
-out:
-	return;
 }
diff --git a/tools/testing/selftests/bpf/prog_tests/fib_lookup.c b/tools/testing/selftests/bpf/prog_tests/fib_lookup.c
index bd7658958004..b7eac1fce746 100644
--- a/tools/testing/selftests/bpf/prog_tests/fib_lookup.c
+++ b/tools/testing/selftests/bpf/prog_tests/fib_lookup.c
@@ -315,9 +315,7 @@ void test_fib_lookup(void)
 		return;
 	prog_fd = bpf_program__fd(skel->progs.fib_lookup);
 
-	SYS(fail, "ip netns add %s", NS_TEST);
-
-	nstoken = open_netns(NS_TEST);
+	nstoken = create_netns(NS_TEST);
 	if (!ASSERT_OK_PTR(nstoken, "open_netns"))
 		goto fail;
 
diff --git a/tools/testing/selftests/bpf/prog_tests/ns_current_pid_tgid.c b/tools/testing/selftests/bpf/prog_tests/ns_current_pid_tgid.c
index e72d75d6baa7..6dae14d106ac 100644
--- a/tools/testing/selftests/bpf/prog_tests/ns_current_pid_tgid.c
+++ b/tools/testing/selftests/bpf/prog_tests/ns_current_pid_tgid.c
@@ -204,10 +204,7 @@ static void test_in_netns(int (*fn)(void *), void *arg)
 {
 	struct nstoken *nstoken = NULL;
 
-	SYS(cleanup, "ip netns add ns_current_pid_tgid");
-	SYS(cleanup, "ip -net ns_current_pid_tgid link set dev lo up");
-
-	nstoken = open_netns("ns_current_pid_tgid");
+	nstoken = create_netns("ns_current_pid_tgid");
 	if (!ASSERT_OK_PTR(nstoken, "open_netns"))
 		goto cleanup;
 
diff --git a/tools/testing/selftests/bpf/prog_tests/sock_destroy.c b/tools/testing/selftests/bpf/prog_tests/sock_destroy.c
index 9c11938fe597..c156218c7280 100644
--- a/tools/testing/selftests/bpf/prog_tests/sock_destroy.c
+++ b/tools/testing/selftests/bpf/prog_tests/sock_destroy.c
@@ -193,10 +193,7 @@ void test_sock_destroy(void)
 	if (!ASSERT_OK_PTR(skel->links.sock_connect, "prog_attach"))
 		goto cleanup;
 
-	SYS(cleanup, "ip netns add %s", TEST_NS);
-	SYS(cleanup, "ip -net %s link set dev lo up", TEST_NS);
-
-	nstoken = open_netns(TEST_NS);
+	nstoken = create_netns(TEST_NS);
 	if (!ASSERT_OK_PTR(nstoken, "open_netns"))
 		goto cleanup;
 
diff --git a/tools/testing/selftests/bpf/prog_tests/sock_iter_batch.c b/tools/testing/selftests/bpf/prog_tests/sock_iter_batch.c
index d56e18b25528..b82ab5ddd9e6 100644
--- a/tools/testing/selftests/bpf/prog_tests/sock_iter_batch.c
+++ b/tools/testing/selftests/bpf/prog_tests/sock_iter_batch.c
@@ -112,11 +112,7 @@ void test_sock_iter_batch(void)
 {
 	struct nstoken *nstoken = NULL;
 
-	SYS_NOFAIL("ip netns del " TEST_NS);
-	SYS(done, "ip netns add %s", TEST_NS);
-	SYS(done, "ip -net %s link set dev lo up", TEST_NS);
-
-	nstoken = open_netns(TEST_NS);
+	nstoken = create_netns(TEST_NS);
 	if (!ASSERT_OK_PTR(nstoken, "open_netns"))
 		goto done;
 
-- 
2.43.0