selftests: forwarding: Add a tunnel-based test for L3 HW stats

Add a selftest that uses an IPIP topology and tests that L3 HW stats
reflect the traffic in the tunnel.
Signed-off-by: Petr Machata <petrm@nvidia.com>
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

tools/testing/selftests/net/forwarding/Makefile

@@ -20,6 +20,7 @@ TEST_PROGS = bridge_igmp.sh \
 	gre_multipath_nh.sh \
 	gre_multipath.sh \
 	hw_stats_l3.sh \
+	hw_stats_l3_gre.sh \
 	ip6_forward_instats_vrf.sh \
 	ip6gre_custom_multipath_hash.sh \
 	ip6gre_flat_key.sh \

tools/testing/selftests/net/forwarding/hw_stats_l3_gre.sh

+#!/bin/bash
+# SPDX-License-Identifier: GPL-2.0
+
+# Test L3 stats on IP-in-IP GRE tunnel without key.
+
+# This test uses flat topology for IP tunneling tests. See ipip_lib.sh for more
+# details.
+
+ALL_TESTS="
+	ping_ipv4
+	test_stats_rx
+	test_stats_tx
+"
+NUM_NETIFS=6
+source lib.sh
+source ipip_lib.sh
+
+setup_prepare()
+{
+	h1=${NETIFS[p1]}
+	ol1=${NETIFS[p2]}
+
+	ul1=${NETIFS[p3]}
+	ul2=${NETIFS[p4]}
+
+	ol2=${NETIFS[p5]}
+	h2=${NETIFS[p6]}
+
+	ol1mac=$(mac_get $ol1)
+
+	forwarding_enable
+	vrf_prepare
+	h1_create
+	h2_create
+	sw1_flat_create gre $ol1 $ul1
+	sw2_flat_create gre $ol2 $ul2
+	ip stats set dev g1a l3_stats on
+	ip stats set dev g2a l3_stats on
+}
+
+cleanup()
+{
+	pre_cleanup
+
+	ip stats set dev g1a l3_stats off
+	ip stats set dev g2a l3_stats off
+
+	sw2_flat_destroy $ol2 $ul2
+	sw1_flat_destroy $ol1 $ul1
+	h2_destroy
+	h1_destroy
+
+	vrf_cleanup
+	forwarding_restore
+}
+
+ping_ipv4()
+{
+	RET=0
+
+	ping_test $h1 192.0.2.18 " gre flat"
+}
+
+send_packets_ipv4()
+{
+	# Send 21 packets instead of 20, because the first one might trap and go
+	# through the SW datapath, which might not bump the HW counter.
+	$MZ $h1 -c 21 -d 20msec -p 100 \
+	    -a own -b $ol1mac -A 192.0.2.1 -B 192.0.2.18 \
+	    -q -t udp sp=54321,dp=12345
+}
+
+test_stats()
+{
+	local dev=$1; shift
+	local dir=$1; shift
+
+	local a
+	local b
+
+	RET=0
+
+	a=$(hw_stats_get l3_stats $dev $dir packets)
+	send_packets_ipv4
+	b=$(busywait "$TC_HIT_TIMEOUT" until_counter_is ">= $a + 20" \
+		     hw_stats_get l3_stats $dev $dir packets)
+	check_err $? "Traffic not reflected in the counter: $a -> $b"
+
+	log_test "Test $dir packets: $prot"
+}
+
+test_stats_tx()
+{
+	test_stats g1a tx
+}
+
+test_stats_rx()
+{
+	test_stats g2a rx
+}
+
+trap cleanup EXIT
+
+setup_prepare
+setup_wait
+
+tests_run
+
+exit $EXIT_STATUS