From: Menglong Dong <imagedong@tencent.com>

Add the function chk_msk_inuse() to diag.sh, which is used to check the
statistics of mptcp socket in use. As mptcp socket in listen state will
be closed randomly after 'accept', we need to get the count of listening
mptcp socket through 'ss' command.

mptcp_connect command with '-r' flag seems won't exit after flush_pids,
therefore we need consider this additional statistics. But after the
second flush_pids, it will exit.

All tests pass.

Signed-off-by: Menglong Dong <imagedong@tencent.com>
---
 tools/testing/selftests/net/mptcp/diag.sh | 28 +++++++++++++++++++++++
 1 file changed, 28 insertions(+)

diff --git a/tools/testing/selftests/net/mptcp/diag.sh b/tools/testing/selftests/net/mptcp/diag.sh
index 515859a5168b..d969cb45b8a9 100755
--- a/tools/testing/selftests/net/mptcp/diag.sh
+++ b/tools/testing/selftests/net/mptcp/diag.sh
@@ -141,6 +141,28 @@ chk_msk_listen()
 	nr=$(ss -Ml $filter | wc -l)
 }
 
+chk_msk_inuse()
+{
+	local nr listen_nr
+	local expected=$1
+
+	shift 1
+	msg=$*
+
+	nr=$(ip netns exec $ns awk '$1~/^MPTCP$/{print $3}' /proc/net/protocols)
+	listen_nr=$(ss -N $ns -Ml | grep -c LISTEN)
+	expected=$(($expected+$listen_nr))
+
+	printf "%-50s" "$msg"
+
+	if [ $nr != $expected ]; then
+		echo "[ fail ] expected $expected found $nr"
+		ret=$test_cnt
+	else
+		echo "[  ok  ]"
+	fi
+}
+
 # $1: ns, $2: port
 wait_local_port_listen()
 {
@@ -194,8 +216,11 @@ wait_connected $ns 10000
 chk_msk_nr 2 "after MPC handshake "
 chk_msk_remote_key_nr 2 "....chk remote_key"
 chk_msk_fallback_nr 0 "....chk no fallback"
+chk_msk_inuse 2 "msk in use statistics"
 flush_pids
 
+# with '-r' flag, client won't exit after flush_pids
+chk_msk_inuse 1 "msk in use statistics"
 
 echo "a" | \
 	timeout ${timeout_test} \
@@ -231,6 +256,9 @@ for I in `seq 1 $NR_CLIENTS`; do
 done
 
 wait_msk_nr $((NR_CLIENTS*2)) "many msk socket present"
+chk_msk_inuse $((NR_CLIENTS*2+1)) "msk in use statistics"
 flush_pids
 
+chk_msk_inuse 0 "msk in use statistics"
+
 exit $ret
-- 
2.37.2

Hi Menglong,

Thank you for your modifications, that's great!

Our CI did some validations and here is its report:

- KVM Validation: normal:
  - Unstable: 1 failed test(s): selftest_mptcp_join 🔴:
  - Task: https://cirrus-ci.com/task/5793338778451968
  - Summary: https://api.cirrus-ci.com/v1/artifact/task/5793338778451968/summary/summary.txt

- KVM Validation: debug:
  - Unstable: 1 failed test(s): selftest_mptcp_join 🔴:
  - Task: https://cirrus-ci.com/task/5230388825030656
  - Summary: https://api.cirrus-ci.com/v1/artifact/task/5230388825030656/summary/summary.txt

Initiator: Patchew Applier
Commits: https://github.com/multipath-tcp/mptcp_net-next/commits/abf5029a32b9


If there are some issues, you can reproduce them using the same environment as
the one used by the CI thanks to a docker image, e.g.:

    $ cd [kernel source code]
    $ docker run -v "${PWD}:${PWD}:rw" -w "${PWD}" --privileged --rm -it \
        --pull always mptcp/mptcp-upstream-virtme-docker:latest \
        auto-debug

For more details:

    https://github.com/multipath-tcp/mptcp-upstream-virtme-docker


Please note that despite all the efforts that have been already done to have a
stable tests suite when executed on a public CI like here, it is possible some
reported issues are not due to your modifications. Still, do not hesitate to
help us improve that ;-)

Cheers,
MPTCP GH Action bot
Bot operated by Matthieu Baerts (Tessares)