selftests: mptcp: join: skip Fastclose tests if not supported

commit ae947bb2c253ff5f395bb70cb9db8700543bf398 upstream.

Selftests are supposed to run on any kernels, including the old ones not
supporting all MPTCP features.

One of them is the support of MP_FASTCLOSE introduced in commit
f284c0c77321 ("mptcp: implement fastclose xmit path").

If the MIB counter is not available, the test cannot be verified and the
behaviour will not be the expected one. So we can skip the test if the
counter is missing.

Link: https://github.com/multipath-tcp/mptcp_net-next/issues/368
Fixes: 01542c9bf9ab ("selftests: mptcp: add fastclose testcase")
Cc: stable@vger.kernel.org
Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/tools/testing/selftests/net/mptcp/mptcp_join.sh b/tools/testing/selftests/net/mptcp/mptcp_join.sh
index 61cbc10..6fa3bf7 100755 (executable)
--- a/tools/testing/selftests/net/mptcp/mptcp_join.sh
+++ b/tools/testing/selftests/net/mptcp/mptcp_join.sh
@@ -253,6 +253,19 @@ reset()
        return 0
 }
 
+# $1: test name ; $2: counter to check
+reset_check_counter()
+{
+       reset "${1}" || return 1
+
+       local counter="${2}"
+
+       if ! nstat -asz "${counter}" | grep -wq "${counter}"; then
+               mark_as_skipped "counter '${counter}' is not available"
+               return 1
+       fi
+}
+
 # $1: test name
 reset_with_cookies()
 {
@@ -2959,14 +2972,14 @@ fullmesh_tests()
 
 fastclose_tests()
 {
-       if reset "fastclose test"; then
+       if reset_check_counter "fastclose test" "MPTcpExtMPFastcloseTx"; then
                run_tests $ns1 $ns2 10.0.1.1 1024 0 fastclose_client
                chk_join_nr 0 0 0
                chk_fclose_nr 1 1
                chk_rst_nr 1 1 invert
        fi
 
-       if reset "fastclose server test"; then
+       if reset_check_counter "fastclose server test" "MPTcpExtMPFastcloseRx"; then
                run_tests $ns1 $ns2 10.0.1.1 1024 0 fastclose_server
                chk_join_nr 0 0 0
                chk_fclose_nr 1 1 invert