selftests: mlxsw: Add tc sample tests

Test that packets are sampled when tc-sample is used and that reported
metadata is correct. Two sets of hosts (with and without LAG) are used,
since metadata extraction in mlxsw is a bit different when LAG is
involved.

 # ./tc_sample.sh
 TEST: tc sample rate (forward)                                      [ OK ]
 TEST: tc sample rate (local receive)                                [ OK ]
 TEST: tc sample maximum rate                                        [ OK ]
 TEST: tc sample group conflict test                                 [ OK ]
 TEST: tc sample iif                                                 [ OK ]
 TEST: tc sample lag iif                                             [ OK ]
 TEST: tc sample oif                                                 [ OK ]
 TEST: tc sample lag oif                                             [ OK ]
 TEST: tc sample out-tc                                              [ OK ]
 TEST: tc sample out-tc-occ                                          [ OK ]

Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 492 insertions, 0 deletions

diff --git a/tools/testing/selftests/drivers/net/mlxsw/tc_sample.sh b/tools/testing/selftests/drivers/net/mlxsw/tc_sample.sh
new file mode 100755
index 000000000000..75d00104f291
--- /dev/null
+++ b/tools/testing/selftests/drivers/net/mlxsw/tc_sample.sh
@@ -0,0 +1,492 @@
+#!/bin/bash
+# SPDX-License-Identifier: GPL-2.0
+#
+# Test that packets are sampled when tc-sample is used and that reported
+# metadata is correct. Two sets of hosts (with and without LAG) are used, since
+# metadata extraction in mlxsw is a bit different when LAG is involved.
+#
+# +---------------------------------+       +---------------------------------+
+# | H1 (vrf)                        |       | H3 (vrf)                        |
+# |    + $h1                        |       |    + $h3_lag                    |
+# |    | 192.0.2.1/28               |       |    | 192.0.2.17/28              |
+# |    |                            |       |    |                            |
+# |    |  default via 192.0.2.2     |       |    |  default via 192.0.2.18    |
+# +----|----------------------------+       +----|----------------------------+
+#      |                                         |
+# +----|-----------------------------------------|----------------------------+
+# |    | 192.0.2.2/28                            | 192.0.2.18/28              |
+# |    + $rp1                                    + $rp3_lag                   |
+# |                                                                           |
+# |    + $rp2                                    + $rp4_lag                   |
+# |    | 198.51.100.2/28                         | 198.51.100.18/28           |
+# +----|-----------------------------------------|----------------------------+
+#      |                                         |
+# +----|----------------------------+       +----|----------------------------+
+# |    |  default via 198.51.100.2  |       |    |  default via 198.51.100.18 |
+# |    |                            |       |    |                            |
+# |    | 198.51.100.1/28            |       |    | 198.51.100.17/28           |
+# |    + $h2                        |       |    + $h4_lag                    |
+# | H2 (vrf)                        |       | H4 (vrf)                        |
+# +---------------------------------+       +---------------------------------+
+
+lib_dir=$(dirname $0)/../../../net/forwarding
+
+ALL_TESTS="
+	tc_sample_rate_test
+	tc_sample_max_rate_test
+	tc_sample_group_conflict_test
+	tc_sample_md_iif_test
+	tc_sample_md_lag_iif_test
+	tc_sample_md_oif_test
+	tc_sample_md_lag_oif_test
+	tc_sample_md_out_tc_test
+	tc_sample_md_out_tc_occ_test
+"
+NUM_NETIFS=8
+CAPTURE_FILE=$(mktemp)
+source $lib_dir/lib.sh
+source $lib_dir/devlink_lib.sh
+
+# Available at https://github.com/Mellanox/libpsample
+require_command psample
+
+h1_create()
+{
+	simple_if_init $h1 192.0.2.1/28
+
+	ip -4 route add default vrf v$h1 nexthop via 192.0.2.2
+}
+
+h1_destroy()
+{
+	ip -4 route del default vrf v$h1 nexthop via 192.0.2.2
+
+	simple_if_fini $h1 192.0.2.1/28
+}
+
+h2_create()
+{
+	simple_if_init $h2 198.51.100.1/28
+
+	ip -4 route add default vrf v$h2 nexthop via 198.51.100.2
+}
+
+h2_destroy()
+{
+	ip -4 route del default vrf v$h2 nexthop via 198.51.100.2
+
+	simple_if_fini $h2 198.51.100.1/28
+}
+
+h3_create()
+{
+	ip link set dev $h3 down
+	ip link add name ${h3}_bond type bond mode 802.3ad
+	ip link set dev $h3 master ${h3}_bond
+
+	simple_if_init ${h3}_bond 192.0.2.17/28
+
+	ip -4 route add default vrf v${h3}_bond nexthop via 192.0.2.18
+}
+
+h3_destroy()
+{
+	ip -4 route del default vrf v${h3}_bond nexthop via 192.0.2.18
+
+	simple_if_fini ${h3}_bond 192.0.2.17/28
+
+	ip link set dev $h3 nomaster
+	ip link del dev ${h3}_bond
+}
+
+h4_create()
+{
+	ip link set dev $h4 down
+	ip link add name ${h4}_bond type bond mode 802.3ad
+	ip link set dev $h4 master ${h4}_bond
+
+	simple_if_init ${h4}_bond 198.51.100.17/28
+
+	ip -4 route add default vrf v${h4}_bond nexthop via 198.51.100.18
+}
+
+h4_destroy()
+{
+	ip -4 route del default vrf v${h4}_bond nexthop via 198.51.100.18
+
+	simple_if_fini ${h4}_bond 198.51.100.17/28
+
+	ip link set dev $h4 nomaster
+	ip link del dev ${h4}_bond
+}
+
+router_create()
+{
+	ip link set dev $rp1 up
+	__addr_add_del $rp1 add 192.0.2.2/28
+	tc qdisc add dev $rp1 clsact
+
+	ip link set dev $rp2 up
+	__addr_add_del $rp2 add 198.51.100.2/28
+	tc qdisc add dev $rp2 clsact
+
+	ip link add name ${rp3}_bond type bond mode 802.3ad
+	ip link set dev $rp3 master ${rp3}_bond
+	__addr_add_del ${rp3}_bond add 192.0.2.18/28
+	tc qdisc add dev $rp3 clsact
+	ip link set dev ${rp3}_bond up
+
+	ip link add name ${rp4}_bond type bond mode 802.3ad
+	ip link set dev $rp4 master ${rp4}_bond
+	__addr_add_del ${rp4}_bond add 198.51.100.18/28
+	tc qdisc add dev $rp4 clsact
+	ip link set dev ${rp4}_bond up
+}
+
+router_destroy()
+{
+	ip link set dev ${rp4}_bond down
+	tc qdisc del dev $rp4 clsact
+	__addr_add_del ${rp4}_bond del 198.51.100.18/28
+	ip link set dev $rp4 nomaster
+	ip link del dev ${rp4}_bond
+
+	ip link set dev ${rp3}_bond down
+	tc qdisc del dev $rp3 clsact
+	__addr_add_del ${rp3}_bond del 192.0.2.18/28
+	ip link set dev $rp3 nomaster
+	ip link del dev ${rp3}_bond
+
+	tc qdisc del dev $rp2 clsact
+	__addr_add_del $rp2 del 198.51.100.2/28
+	ip link set dev $rp2 down
+
+	tc qdisc del dev $rp1 clsact
+	__addr_add_del $rp1 del 192.0.2.2/28
+	ip link set dev $rp1 down
+}
+
+setup_prepare()
+{
+	h1=${NETIFS[p1]}
+	rp1=${NETIFS[p2]}
+	rp2=${NETIFS[p3]}
+	h2=${NETIFS[p4]}
+	h3=${NETIFS[p5]}
+	rp3=${NETIFS[p6]}
+	h4=${NETIFS[p7]}
+	rp4=${NETIFS[p8]}
+
+	vrf_prepare
+
+	h1_create
+	h2_create
+	h3_create
+	h4_create
+	router_create
+}
+
+cleanup()
+{
+	pre_cleanup
+
+	rm -f $CAPTURE_FILE
+
+	router_destroy
+	h4_destroy
+	h3_destroy
+	h2_destroy
+	h1_destroy
+
+	vrf_cleanup
+}
+
+psample_capture_start()
+{
+	rm -f $CAPTURE_FILE
+
+	psample &> $CAPTURE_FILE &
+
+	sleep 1
+}
+
+psample_capture_stop()
+{
+	{ kill %% && wait %%; } 2>/dev/null
+}
+
+__tc_sample_rate_test()
+{
+	local desc=$1; shift
+	local dip=$1; shift
+	local pkts pct
+
+	RET=0
+
+	tc filter add dev $rp1 ingress protocol all pref 1 handle 101 matchall \
+		skip_sw action sample rate 32 group 1
+	check_err $? "Failed to configure sampling rule"
+
+	psample_capture_start
+
+	ip vrf exec v$h1 $MZ $h1 -c 3200 -d 1msec -p 64 -A 192.0.2.1 \
+		-B $dip -t udp dp=52768,sp=42768 -q
+
+	psample_capture_stop
+
+	pkts=$(grep -e "group 1 " $CAPTURE_FILE | wc -l)
+	pct=$((100 * (pkts - 100) / 100))
+	(( -25 <= pct && pct <= 25))
+	check_err $? "Expected 100 packets, got $pkts packets, which is $pct% off. Required accuracy is +-25%"
+
+	log_test "tc sample rate ($desc)"
+
+	tc filter del dev $rp1 ingress protocol all pref 1 handle 101 matchall
+}
+
+tc_sample_rate_test()
+{
+	__tc_sample_rate_test "forward" 198.51.100.1
+	__tc_sample_rate_test "local receive" 192.0.2.2
+}
+
+tc_sample_max_rate_test()
+{
+	RET=0
+
+	tc filter add dev $rp1 ingress protocol all pref 1 handle 101 matchall \
+		skip_sw action sample rate $((35 * 10 ** 8)) group 1
+	check_err $? "Failed to configure sampling rule with max rate"
+
+	tc filter del dev $rp1 ingress protocol all pref 1 handle 101 matchall
+
+	tc filter add dev $rp1 ingress protocol all pref 1 handle 101 matchall \
+		skip_sw action sample rate $((35 * 10 ** 8 + 1)) \
+		group 1 &> /dev/null
+	check_fail $? "Managed to configure sampling rate above maximum"
+
+	log_test "tc sample maximum rate"
+}
+
+tc_sample_group_conflict_test()
+{
+	RET=0
+
+	# Test that two sampling rules cannot be configured on the same port
+	# with different groups.
+
+	tc filter add dev $rp1 ingress protocol all pref 1 handle 101 matchall \
+		skip_sw action sample rate 1024 group 1
+	check_err $? "Failed to configure sampling rule"
+
+	tc filter add dev $rp1 ingress protocol all pref 2 handle 102 matchall \
+		skip_sw action sample rate 1024 group 2 &> /dev/null
+	check_fail $? "Managed to configure sampling rule with conflicting group"
+
+	log_test "tc sample group conflict test"
+
+	tc filter del dev $rp1 ingress protocol all pref 1 handle 101 matchall
+}
+
+tc_sample_md_iif_test()
+{
+	local rp1_ifindex
+
+	RET=0
+
+	tc filter add dev $rp1 ingress protocol all pref 1 handle 101 matchall \
+		skip_sw action sample rate 5 group 1
+	check_err $? "Failed to configure sampling rule"
+
+	psample_capture_start
+
+	ip vrf exec v$h1 $MZ $h1 -c 3200 -d 1msec -p 64 -A 192.0.2.1 \
+		-B 198.51.100.1 -t udp dp=52768,sp=42768 -q
+
+	psample_capture_stop
+
+	rp1_ifindex=$(ip -j -p link show dev $rp1 | jq '.[]["ifindex"]')
+	grep -q -e "in-ifindex $rp1_ifindex " $CAPTURE_FILE
+	check_err $? "Sampled packets do not have expected in-ifindex"
+
+	log_test "tc sample iif"
+
+	tc filter del dev $rp1 ingress protocol all pref 1 handle 101 matchall
+}
+
+tc_sample_md_lag_iif_test()
+{
+	local rp3_ifindex
+
+	RET=0
+
+	tc filter add dev $rp3 ingress protocol all pref 1 handle 101 matchall \
+		skip_sw action sample rate 5 group 1
+	check_err $? "Failed to configure sampling rule"
+
+	psample_capture_start
+
+	ip vrf exec v${h3}_bond $MZ ${h3}_bond -c 3200 -d 1msec -p 64 \
+		-A 192.0.2.17 -B 198.51.100.17 -t udp dp=52768,sp=42768 -q
+
+	psample_capture_stop
+
+	rp3_ifindex=$(ip -j -p link show dev $rp3 | jq '.[]["ifindex"]')
+	grep -q -e "in-ifindex $rp3_ifindex " $CAPTURE_FILE
+	check_err $? "Sampled packets do not have expected in-ifindex"
+
+	log_test "tc sample lag iif"
+
+	tc filter del dev $rp3 ingress protocol all pref 1 handle 101 matchall
+}
+
+tc_sample_md_oif_test()
+{
+	local rp2_ifindex
+
+	RET=0
+
+	tc filter add dev $rp1 ingress protocol all pref 1 handle 101 matchall \
+		skip_sw action sample rate 5 group 1
+	check_err $? "Failed to configure sampling rule"
+
+	psample_capture_start
+
+	ip vrf exec v$h1 $MZ $h1 -c 3200 -d 1msec -p 64 -A 192.0.2.1 \
+		-B 198.51.100.1 -t udp dp=52768,sp=42768 -q
+
+	psample_capture_stop
+
+	rp2_ifindex=$(ip -j -p link show dev $rp2 | jq '.[]["ifindex"]')
+	grep -q -e "out-ifindex $rp2_ifindex " $CAPTURE_FILE
+	check_err $? "Sampled packets do not have expected out-ifindex"
+
+	log_test "tc sample oif"
+
+	tc filter del dev $rp1 ingress protocol all pref 1 handle 101 matchall
+}
+
+tc_sample_md_lag_oif_test()
+{
+	local rp4_ifindex
+
+	RET=0
+
+	tc filter add dev $rp3 ingress protocol all pref 1 handle 101 matchall \
+		skip_sw action sample rate 5 group 1
+	check_err $? "Failed to configure sampling rule"
+
+	psample_capture_start
+
+	ip vrf exec v${h3}_bond $MZ ${h3}_bond -c 3200 -d 1msec -p 64 \
+		-A 192.0.2.17 -B 198.51.100.17 -t udp dp=52768,sp=42768 -q
+
+	psample_capture_stop
+
+	rp4_ifindex=$(ip -j -p link show dev $rp4 | jq '.[]["ifindex"]')
+	grep -q -e "out-ifindex $rp4_ifindex " $CAPTURE_FILE
+	check_err $? "Sampled packets do not have expected out-ifindex"
+
+	log_test "tc sample lag oif"
+
+	tc filter del dev $rp3 ingress protocol all pref 1 handle 101 matchall
+}
+
+tc_sample_md_out_tc_test()
+{
+	RET=0
+
+	# Output traffic class is not supported on Spectrum-1.
+	[[ "$DEVLINK_VIDDID" == "15b3:cb84" ]] && return
+
+	tc filter add dev $rp1 ingress protocol all pref 1 handle 101 matchall \
+		skip_sw action sample rate 5 group 1
+	check_err $? "Failed to configure sampling rule"
+
+	# By default, all the packets should go to the same traffic class (0).
+
+	psample_capture_start
+
+	ip vrf exec v$h1 $MZ $h1 -c 3200 -d 1msec -p 64 -A 192.0.2.1 \
+		-B 198.51.100.1 -t udp dp=52768,sp=42768 -q
+
+	psample_capture_stop
+
+	grep -q -e "out-tc 0 " $CAPTURE_FILE
+	check_err $? "Sampled packets do not have expected out-tc (0)"
+
+	# Map all priorities to highest traffic class (7) and check reported
+	# out-tc.
+	tc qdisc replace dev $rp2 root handle 1: \
+		prio bands 3 priomap 0 0 0 0 0 0 0 0
+
+	psample_capture_start
+
+	ip vrf exec v$h1 $MZ $h1 -c 3200 -d 1msec -p 64 -A 192.0.2.1 \
+		-B 198.51.100.1 -t udp dp=52768,sp=42768 -q
+
+	psample_capture_stop
+
+	grep -q -e "out-tc 7 " $CAPTURE_FILE
+	check_err $? "Sampled packets do not have expected out-tc (7)"
+
+	log_test "tc sample out-tc"
+
+	tc qdisc del dev $rp2 root handle 1:
+	tc filter del dev $rp1 ingress protocol all pref 1 handle 101 matchall
+}
+
+tc_sample_md_out_tc_occ_test()
+{
+	local backlog pct occ
+
+	RET=0
+
+	# Output traffic class occupancy is not supported on Spectrum-1.
+	[[ "$DEVLINK_VIDDID" == "15b3:cb84" ]] && return
+
+	tc filter add dev $rp1 ingress protocol all pref 1 handle 101 matchall \
+		skip_sw action sample rate 1024 group 1
+	check_err $? "Failed to configure sampling rule"
+
+	# Configure a shaper on egress to create congestion.
+	tc qdisc replace dev $rp2 root handle 1: \
+		tbf rate 1Mbit burst 256k limit 1M
+
+	psample_capture_start
+
+	ip vrf exec v$h1 $MZ $h1 -c 0 -d 1usec -p 1400 -A 192.0.2.1 \
+		-B 198.51.100.1 -t udp dp=52768,sp=42768 -q &
+
+	# Allow congestion to reach steady state.
+	sleep 10
+
+	backlog=$(tc -j -p -s qdisc show dev $rp2 | jq '.[0]["backlog"]')
+
+	# Kill mausezahn.
+	{ kill %% && wait %%; } 2>/dev/null
+
+	psample_capture_stop
+
+	# Record last congestion sample.
+	occ=$(grep -e "out-tc-occ " $CAPTURE_FILE | tail -n 1 | \
+		cut -d ' ' -f 16)
+
+	pct=$((100 * (occ - backlog) / backlog))
+	(( -1 <= pct && pct <= 1))
+	check_err $? "Recorded a congestion of $backlog bytes, but sampled congestion is $occ bytes, which is $pct% off. Required accuracy is +-5%"
+
+	log_test "tc sample out-tc-occ"
+
+	tc qdisc del dev $rp2 root handle 1:
+	tc filter del dev $rp1 ingress protocol all pref 1 handle 101 matchall
+}
+
+trap cleanup EXIT
+
+setup_prepare
+setup_wait
+
+tests_run
+
+exit $EXIT_STATUS