selftests: forwarding: Add a test for NH group stats

Add to lib.sh support for fetching NH stats, and a new library,
router_mpath_nh_lib.sh, with the common code for testing NH stats.
Use the latter from router_mpath_nh.sh and router_mpath_nh_res.sh.

The test works by sending traffic through a NH group, and checking that the
reported values correspond to what the link that ultimately receives the
traffic reports having seen.

Signed-off-by: Petr Machata <petrm@nvidia.com>
Link: https://lore.kernel.org/r/2a424c54062a5f1efd13b9ec5b2b0e29c6af2574.1709901020.git.petrm@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

5 files changed, 190 insertions, 0 deletions

diff --git a/tools/testing/selftests/net/forwarding/Makefile b/tools/testing/selftests/net/forwarding/Makefile
index cdefc9a5ec34..535865b3d1d6 100644
--- a/tools/testing/selftests/net/forwarding/Makefile
+++ b/tools/testing/selftests/net/forwarding/Makefile
@@ -123,6 +123,7 @@ TEST_FILES := devlink_lib.sh \
 	mirror_gre_topo_lib.sh \
 	mirror_lib.sh \
 	mirror_topo_lib.sh \
+	router_mpath_nh_lib.sh \
 	sch_ets_core.sh \
 	sch_ets_tests.sh \
 	sch_tbf_core.sh \
diff --git a/tools/testing/selftests/net/forwarding/lib.sh b/tools/testing/selftests/net/forwarding/lib.sh
index d1bf39eaf2b3..e579c2e0c462 100644
--- a/tools/testing/selftests/net/forwarding/lib.sh
+++ b/tools/testing/selftests/net/forwarding/lib.sh
@@ -900,6 +900,33 @@ hw_stats_get()
 		jq ".[0].stats64.$dir.$stat"
 }
 
+__nh_stats_get()
+{
+	local key=$1; shift
+	local group_id=$1; shift
+	local member_id=$1; shift
+
+	ip -j -s -s nexthop show id $group_id |
+	    jq --argjson member_id "$member_id" --arg key "$key" \
+	       '.[].group_stats[] | select(.id == $member_id) | .[$key]'
+}
+
+nh_stats_get()
+{
+	local group_id=$1; shift
+	local member_id=$1; shift
+
+	__nh_stats_get packets "$group_id" "$member_id"
+}
+
+nh_stats_get_hw()
+{
+	local group_id=$1; shift
+	local member_id=$1; shift
+
+	__nh_stats_get packets_hw "$group_id" "$member_id"
+}
+
 humanize()
 {
 	local speed=$1; shift
@@ -2010,3 +2037,10 @@ bail_on_lldpad()
 		fi
 	fi
 }
+
+absval()
+{
+	local v=$1; shift
+
+	echo $((v > 0 ? v : -v))
+}
diff --git a/tools/testing/selftests/net/forwarding/router_mpath_nh.sh b/tools/testing/selftests/net/forwarding/router_mpath_nh.sh
index 982e0d098ea9..3f0f5dc95542 100755
--- a/tools/testing/selftests/net/forwarding/router_mpath_nh.sh
+++ b/tools/testing/selftests/net/forwarding/router_mpath_nh.sh
@@ -7,9 +7,12 @@ ALL_TESTS="
 	multipath_test
 	ping_ipv4_blackhole
 	ping_ipv6_blackhole
+	nh_stats_test_v4
+	nh_stats_test_v6
 "
 NUM_NETIFS=8
 source lib.sh
+source router_mpath_nh_lib.sh
 
 h1_create()
 {
@@ -325,6 +328,16 @@ ping_ipv6_blackhole()
 	ip -6 nexthop del id 1001
 }
 
+nh_stats_test_v4()
+{
+	__nh_stats_test_v4 mpath
+}
+
+nh_stats_test_v6()
+{
+	__nh_stats_test_v6 mpath
+}
+
 setup_prepare()
 {
 	h1=${NETIFS[p1]}
diff --git a/tools/testing/selftests/net/forwarding/router_mpath_nh_lib.sh b/tools/testing/selftests/net/forwarding/router_mpath_nh_lib.sh
new file mode 100644
index 000000000000..7e7d62161c34
--- /dev/null
+++ b/tools/testing/selftests/net/forwarding/router_mpath_nh_lib.sh
@@ -0,0 +1,129 @@
+# SPDX-License-Identifier: GPL-2.0
+
+nh_stats_do_test()
+{
+	local what=$1; shift
+	local nh1_id=$1; shift
+	local nh2_id=$1; shift
+	local group_id=$1; shift
+	local stats_get=$1; shift
+	local mz="$@"
+
+	local dp
+
+	RET=0
+
+	sleep 2
+	for ((dp=0; dp < 60000; dp += 10000)); do
+		local dd
+		local t0_rp12=$(link_stats_tx_packets_get $rp12)
+		local t0_rp13=$(link_stats_tx_packets_get $rp13)
+		local t0_nh1=$($stats_get $group_id $nh1_id)
+		local t0_nh2=$($stats_get $group_id $nh2_id)
+
+		ip vrf exec vrf-h1 \
+			$mz -q -p 64 -d 0 -t udp \
+				"sp=1024,dp=$((dp))-$((dp + 10000))"
+		sleep 2
+
+		local t1_rp12=$(link_stats_tx_packets_get $rp12)
+		local t1_rp13=$(link_stats_tx_packets_get $rp13)
+		local t1_nh1=$($stats_get $group_id $nh1_id)
+		local t1_nh2=$($stats_get $group_id $nh2_id)
+
+		local d_rp12=$((t1_rp12 - t0_rp12))
+		local d_rp13=$((t1_rp13 - t0_rp13))
+		local d_nh1=$((t1_nh1 - t0_nh1))
+		local d_nh2=$((t1_nh2 - t0_nh2))
+
+		dd=$(absval $((d_rp12 - d_nh1)))
+		((dd < 10))
+		check_err $? "Discrepancy between link and $stats_get: d_rp12=$d_rp12 d_nh1=$d_nh1"
+
+		dd=$(absval $((d_rp13 - d_nh2)))
+		((dd < 10))
+		check_err $? "Discrepancy between link and $stats_get: d_rp13=$d_rp13 d_nh2=$d_nh2"
+	done
+
+	log_test "NH stats test $what"
+}
+
+nh_stats_test_dispatch_swhw()
+{
+	local what=$1; shift
+	local nh1_id=$1; shift
+	local nh2_id=$1; shift
+	local group_id=$1; shift
+	local mz="$@"
+
+	local used
+
+	nh_stats_do_test "$what" "$nh1_id" "$nh2_id" "$group_id" \
+			 nh_stats_get "${mz[@]}"
+
+	used=$(ip -s -j -d nexthop show id $group_id |
+		   jq '.[].hw_stats.used')
+	kind=$(ip -j -d link show dev $rp11 |
+		   jq -r '.[].linkinfo.info_kind')
+	if [[ $used == true ]]; then
+		nh_stats_do_test "HW $what" "$nh1_id" "$nh2_id" "$group_id" \
+				 nh_stats_get_hw "${mz[@]}"
+	elif [[ $kind == veth ]]; then
+		log_test_skip "HW stats not offloaded on veth topology"
+	fi
+}
+
+nh_stats_test_dispatch()
+{
+	local nhgtype=$1; shift
+	local what=$1; shift
+	local nh1_id=$1; shift
+	local nh2_id=$1; shift
+	local group_id=$1; shift
+	local mz="$@"
+
+	local enabled
+	local kind
+
+	if ! ip nexthop help 2>&1 | grep -q hw_stats; then
+		log_test_skip "NH stats test: ip doesn't support HW stats"
+		return
+	fi
+
+	ip nexthop replace id $group_id group $nh1_id/$nh2_id \
+			   hw_stats on type $nhgtype
+	enabled=$(ip -s -j -d nexthop show id $group_id |
+		      jq '.[].hw_stats.enabled')
+	if [[ $enabled == true ]]; then
+		nh_stats_test_dispatch_swhw "$what" "$nh1_id" "$nh2_id" \
+					    "$group_id" "${mz[@]}"
+	elif [[ $enabled == false ]]; then
+		check_err 1 "HW stats still disabled after enabling"
+		log_test "NH stats test"
+	else
+		log_test_skip "NH stats test: ip doesn't report hw_stats info"
+	fi
+
+	ip nexthop replace id $group_id group $nh1_id/$nh2_id \
+			   hw_stats off type $nhgtype
+}
+
+__nh_stats_test_v4()
+{
+	local nhgtype=$1; shift
+
+	sysctl_set net.ipv4.fib_multipath_hash_policy 1
+	nh_stats_test_dispatch $nhgtype "IPv4" 101 102 103 \
+			       $MZ $h1 -A 192.0.2.2 -B 198.51.100.2
+	sysctl_restore net.ipv4.fib_multipath_hash_policy
+}
+
+__nh_stats_test_v6()
+{
+	local nhgtype=$1; shift
+
+	sysctl_set net.ipv6.fib_multipath_hash_policy 1
+	nh_stats_test_dispatch $nhgtype "IPv6" 104 105 106 \
+			       $MZ -6 $h1 -A 2001:db8:1::2 -B 2001:db8:2::2
+	sysctl_restore net.ipv6.fib_multipath_hash_policy
+}
diff --git a/tools/testing/selftests/net/forwarding/router_mpath_nh_res.sh b/tools/testing/selftests/net/forwarding/router_mpath_nh_res.sh
index a60ff54723b7..4b483d24ad00 100755
--- a/tools/testing/selftests/net/forwarding/router_mpath_nh_res.sh
+++ b/tools/testing/selftests/net/forwarding/router_mpath_nh_res.sh
@@ -5,9 +5,12 @@ ALL_TESTS="
 	ping_ipv4
 	ping_ipv6
 	multipath_test
+	nh_stats_test_v4
+	nh_stats_test_v6
 "
 NUM_NETIFS=8
 source lib.sh
+source router_mpath_nh_lib.sh
 
 h1_create()
 {
@@ -333,6 +336,16 @@ multipath_test()
 	ip nexthop replace id 106 group 104,1/105,1 type resilient
 }
 
+nh_stats_test_v4()
+{
+	__nh_stats_test_v4 resilient
+}
+
+nh_stats_test_v6()
+{
+	__nh_stats_test_v6 resilient
+}
+
 setup_prepare()
 {
 	h1=${NETIFS[p1]}