selftests: mirror_gre_lag_lacp: Check counters at tunnel

The test works by sending packets through a tunnel, whence they are
forwarded to a LAG. One of the LAG children is removed from the LAG prior
to the exercise, and the test then counts how many packets pass through the
other one. The issue with this is that it counts all packets, not just the
encapsulated ones.

So instead add a second gretap endpoint to receive the sent packets, and
check reception counters there.
Signed-off-by: Petr Machata <petrm@nvidia.com>
Reviewed-by: Danielle Ratson <danieller@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

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

@@ -37,8 +37,14 @@
 # |    \                                              /                       |
 # |     \____________________________________________/                        |
 # |                           |                                               |
-# |                           + lag2 (team)                                   |
-# |                             192.0.2.130/28                                |
+# |                           + lag2 (team)  ------>   + gt4-dst (gretap)     |
+# |                             192.0.2.130/28           loc=192.0.2.130      |
+# |                                                      rem=192.0.2.129      |
+# |                                                      ttl=100              |
+# |                                                      tos=inherit          |
+# |                                                                           |
+# |                                                                           |
+# |                                                                           |
 # |                                                                           |
 # +---------------------------------------------------------------------------+
 
@@ -122,16 +128,21 @@ h3_create()
 {
 	vrf_create vrf-h3
 	ip link set dev vrf-h3 up
-	tc qdisc add dev $h3 clsact
-	tc qdisc add dev $h4 clsact
 	h3_create_team
+
+	tunnel_create gt4-dst gretap 192.0.2.130 192.0.2.129 \
+		      ttl 100 tos inherit
+	ip link set dev gt4-dst master vrf-h3
+	tc qdisc add dev gt4-dst clsact
 }
 
 h3_destroy()
 {
+	tc qdisc del dev gt4-dst clsact
+	ip link set dev gt4-dst nomaster
+	tunnel_destroy gt4-dst
+
 	h3_destroy_team
-	tc qdisc del dev $h4 clsact
-	tc qdisc del dev $h3 clsact
 	ip link set dev vrf-h3 down
 	vrf_destroy vrf-h3
 }
@@ -188,18 +199,12 @@ setup_prepare()
 	h2_create
 	h3_create
 	switch_create
-
-	trap_install $h3 ingress
-	trap_install $h4 ingress
 }
 
 cleanup()
 {
 	pre_cleanup
 
-	trap_uninstall $h4 ingress
-	trap_uninstall $h3 ingress
-
 	switch_destroy
 	h3_destroy
 	h2_destroy
@@ -219,6 +224,7 @@ test_lag_slave()
 
 	mirror_install $swp1 ingress gt4 \
 		       "proto 802.1q flower vlan_id 333 $tcflags"
+	vlan_capture_install gt4-dst "vlan_ethtype ipv4 ip_proto icmp type 8"
 
 	# Move $down_dev away from the team. That will prompt change in
 	# txability of the connected device, without changing its upness. The
@@ -226,13 +232,14 @@ test_lag_slave()
 	# other slave.
 	ip link set dev $down_dev nomaster
 	sleep 2
-	mirror_test vrf-h1 192.0.2.1 192.0.2.18 $up_dev 1 10
+	mirror_test vrf-h1 192.0.2.1 192.0.2.18 gt4-dst 100 10
 
 	# Test lack of connectivity when neither slave is txable.
 	ip link set dev $up_dev nomaster
 	sleep 2
-	mirror_test vrf-h1 192.0.2.1 192.0.2.18 $h3 1 0
-	mirror_test vrf-h1 192.0.2.1 192.0.2.18 $h4 1 0
+	mirror_test vrf-h1 192.0.2.1 192.0.2.18 gt4-dst 100 0
+
+	vlan_capture_uninstall gt4-dst
 	mirror_uninstall $swp1 ingress
 
 	# Recreate H3's team device, because mlxsw, which this test is