selftests: mlxsw: Add a self-test for port-default priority

Send non-IP traffic to a port and observe that it gets prioritized
according to the lldptool app=$prio,1,0 rules.
Signed-off-by: Petr Machata <petrm@mellanox.com>
Reviewed-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

tools/testing/selftests/drivers/net/mlxsw/qos_defprio.sh

+#!/bin/bash
+# SPDX-License-Identifier: GPL-2.0
+
+# Test for port-default priority. Non-IP packets ingress $swp1 and are
+# prioritized according to the default priority specified at the port.
+# rx_octets_prio_* counters are used to verify the prioritization.
+#
+# +-----------------------+
+# | H1                    |
+# |    + $h1              |
+# |    | 192.0.2.1/28     |
+# +----|------------------+
+#      |
+# +----|------------------+
+# | SW |                  |
+# |    + $swp1            |
+# |      192.0.2.2/28     |
+# |      APP=<prio>,1,0   |
+# +-----------------------+
+
+ALL_TESTS="
+	ping_ipv4
+	test_defprio
+"
+
+lib_dir=$(dirname $0)/../../../net/forwarding
+
+NUM_NETIFS=2
+: ${HIT_TIMEOUT:=1000} # ms
+source $lib_dir/lib.sh
+
+declare -a APP
+
+defprio_install()
+{
+	local dev=$1; shift
+	local prio=$1; shift
+	local app="app=$prio,1,0"
+
+	lldptool -T -i $dev -V APP $app >/dev/null
+	lldpad_app_wait_set $dev
+	APP[$prio]=$app
+}
+
+defprio_uninstall()
+{
+	local dev=$1; shift
+	local prio=$1; shift
+	local app=${APP[$prio]}
+
+	lldptool -T -i $dev -V APP -d $app >/dev/null
+	lldpad_app_wait_del
+	unset APP[$prio]
+}
+
+defprio_flush()
+{
+	local dev=$1; shift
+	local prio
+
+	if ((${#APP[@]})); then
+		lldptool -T -i $dev -V APP -d ${APP[@]} >/dev/null
+	fi
+	lldpad_app_wait_del
+	APP=()
+}
+
+h1_create()
+{
+	simple_if_init $h1 192.0.2.1/28
+}
+
+h1_destroy()
+{
+	simple_if_fini $h1 192.0.2.1/28
+}
+
+switch_create()
+{
+	ip link set dev $swp1 up
+	ip addr add dev $swp1 192.0.2.2/28
+}
+
+switch_destroy()
+{
+	defprio_flush $swp1
+	ip addr del dev $swp1 192.0.2.2/28
+	ip link set dev $swp1 down
+}
+
+setup_prepare()
+{
+	h1=${NETIFS[p1]}
+	swp1=${NETIFS[p2]}
+
+	vrf_prepare
+
+	h1_create
+	switch_create
+}
+
+cleanup()
+{
+	pre_cleanup
+
+	switch_destroy
+	h1_destroy
+
+	vrf_cleanup
+}
+
+ping_ipv4()
+{
+	ping_test $h1 192.0.2.2
+}
+
+wait_for_packets()
+{
+	local t0=$1; shift
+	local prio_observe=$1; shift
+
+	local t1=$(ethtool_stats_get $swp1 rx_frames_prio_$prio_observe)
+	local delta=$((t1 - t0))
+	echo $delta
+	((delta >= 10))
+}
+
+__test_defprio()
+{
+	local prio_install=$1; shift
+	local prio_observe=$1; shift
+	local delta
+	local key
+	local i
+
+	RET=0
+
+	defprio_install $swp1 $prio_install
+
+	local t0=$(ethtool_stats_get $swp1 rx_frames_prio_$prio_observe)
+	mausezahn -q $h1 -d 100m -c 10 -t arp reply
+	delta=$(busywait "$HIT_TIMEOUT" wait_for_packets $t0 $prio_observe)
+
+	check_err $? "Default priority $prio_install/$prio_observe: Expected to capture 10 packets, got $delta."
+	log_test "Default priority $prio_install/$prio_observe"
+
+	defprio_uninstall $swp1 $prio_install
+}
+
+test_defprio()
+{
+	local prio
+
+	for prio in {0..7}; do
+		__test_defprio $prio $prio
+	done
+
+	defprio_install $swp1 3
+	__test_defprio 0 3
+	__test_defprio 1 3
+	__test_defprio 2 3
+	__test_defprio 4 4
+	__test_defprio 5 5
+	__test_defprio 6 6
+	__test_defprio 7 7
+	defprio_uninstall $swp1 3
+}
+
+trap cleanup EXIT
+
+setup_prepare
+setup_wait
+
+tests_run
+
+exit $EXIT_STATUS

tools/testing/selftests/net/forwarding/lib.sh

@@ -225,6 +225,29 @@ log_info()
 	echo "INFO: $msg"
 }
 
+busywait()
+{
+	local timeout=$1; shift
+
+	local start_time="$(date -u +%s%3N)"
+	while true
+	do
+		local out
+		out=$("$@")
+		local ret=$?
+		if ((!ret)); then
+			echo -n "$out"
+			return 0
+		fi
+
+		local current_time="$(date -u +%s%3N)"
+		if ((current_time - start_time > timeout)); then
+			echo -n "$out"
+			return 1
+		fi
+	done
+}
+
 setup_wait_dev()
 {
 	local dev=$1; shift