selftests: forwarding: Add tc-police tests for packets per second

Test tc-police action for packets per second.
The test is mainly in scenarios Rx policing and Tx policing.
The test passes with veth pairs ports.
Signed-off-by: Baowen Zheng <baowen.zheng@corigine.com>
Signed-off-by: Simon Horman <simon.horman@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

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

@@ -772,6 +772,15 @@ rate()
 	echo $((8 * (t1 - t0) / interval))
 }
 
+packets_rate()
+{
+	local t0=$1; shift
+	local t1=$1; shift
+	local interval=$1; shift
+
+	echo $(((t1 - t0) / interval))
+}
+
 mac_get()
 {
 	local if_name=$1

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

@@ -35,6 +35,8 @@ ALL_TESTS="
 	police_shared_test
 	police_rx_mirror_test
 	police_tx_mirror_test
+	police_pps_rx_test
+	police_pps_tx_test
 "
 NUM_NETIFS=6
 source tc_common.sh
@@ -290,6 +292,60 @@ police_tx_mirror_test()
 	police_mirror_common_test $rp2 egress "police tx and mirror"
 }
 
+police_pps_common_test()
+{
+	local test_name=$1; shift
+
+	RET=0
+
+	# Rule to measure bandwidth on ingress of $h2
+	tc filter add dev $h2 ingress protocol ip pref 1 handle 101 flower \
+		dst_ip 198.51.100.1 ip_proto udp dst_port 54321 \
+		action drop
+
+	mausezahn $h1 -a own -b $(mac_get $rp1) -A 192.0.2.1 -B 198.51.100.1 \
+		-t udp sp=12345,dp=54321 -p 1000 -c 0 -q &
+
+	local t0=$(tc_rule_stats_get $h2 1 ingress .packets)
+	sleep 10
+	local t1=$(tc_rule_stats_get $h2 1 ingress .packets)
+
+	local er=$((2000))
+	local nr=$(packets_rate $t0 $t1 10)
+	local nr_pct=$((100 * (nr - er) / er))
+	((-10 <= nr_pct && nr_pct <= 10))
+	check_err $? "Expected rate $(humanize $er), got $(humanize $nr), which is $nr_pct% off. Required accuracy is +-10%."
+
+	log_test "$test_name"
+
+	{ kill %% && wait %%; } 2>/dev/null
+	tc filter del dev $h2 ingress protocol ip pref 1 handle 101 flower
+}
+
+police_pps_rx_test()
+{
+	# Rule to police traffic destined to $h2 on ingress of $rp1
+	tc filter add dev $rp1 ingress protocol ip pref 1 handle 101 flower \
+		dst_ip 198.51.100.1 ip_proto udp dst_port 54321 \
+		action police pkts_rate 2000 pkts_burst 400 conform-exceed drop/ok
+
+	police_pps_common_test "police pps on rx"
+
+	tc filter del dev $rp1 ingress protocol ip pref 1 handle 101 flower
+}
+
+police_pps_tx_test()
+{
+	# Rule to police traffic destined to $h2 on egress of $rp2
+	tc filter add dev $rp2 egress protocol ip pref 1 handle 101 flower \
+		dst_ip 198.51.100.1 ip_proto udp dst_port 54321 \
+		action police pkts_rate 2000 pkts_burst 400 conform-exceed drop/ok
+
+	police_pps_common_test "police pps on tx"
+
+	tc filter del dev $rp2 egress protocol ip pref 1 handle 101 flower
+}
+
 setup_prepare()
 {
 	h1=${NETIFS[p1]}