selftests: mlxsw: Add a new test for strict priority

Test that when strict priority is configured on a system, the
higher-priority traffic does actually win all the available bandwidth.
The test uses a similar approach to qos_mc_aware.sh to run and account
the traffic.
Signed-off-by: Petr Machata <petrm@mellanox.com>
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

tools/testing/selftests/drivers/net/mlxsw/qos_ets_strict.sh

+#!/bin/bash
+# SPDX-License-Identifier: GPL-2.0
+#
+# A test for strict prioritization of traffic in the switch. Run two streams of
+# traffic, each through a different ingress port, one tagged with PCP of 1, the
+# other with PCP of 2. Both streams converge at one egress port, where they are
+# assigned TC of, respectively, 1 and 2, with strict priority configured between
+# them. In H3, we expect to see (almost) exclusively the high-priority traffic.
+#
+# Please see qos_mc_aware.sh for an explanation of why we use mausezahn and
+# counters instead of just running iperf3.
+#
+# +---------------------------+                 +-----------------------------+
+# | H1                        |                 |                          H2 |
+# |         $h1.111 +         |                 |         + $h2.222           |
+# |   192.0.2.33/28 |         |                 |         | 192.0.2.65/28     |
+# |   e-qos-map 0:1 |         |                 |         | e-qos-map 0:2     |
+# |                 |         |                 |         |                   |
+# |             $h1 +         |                 |         + $h2               |
+# +-----------------|---------+                 +---------|-------------------+
+#                   |                                     |
+# +-----------------|-------------------------------------|-------------------+
+# |           $swp1 +                                     + $swp2             |
+# |          >1Gbps |                                     | >1Gbps            |
+# | +---------------|-----------+              +----------|----------------+  |
+# | |     $swp1.111 +           |              |          + $swp2.222      |  |
+# | |                     BR111 |       SW     | BR222                     |  |
+# | |     $swp3.111 +           |              |          + $swp3.222      |  |
+# | +---------------|-----------+              +----------|----------------+  |
+# |                 \_____________________________________/                   |
+# |                                    |                                      |
+# |                                    + $swp3                                |
+# |                                    | 1Gbps bottleneck                     |
+# |                                    | ETS: (up n->tc n for n in 0..7)      |
+# |                                    |      strict priority                 |
+# +------------------------------------|--------------------------------------+
+#                                      |
+#                 +--------------------|--------------------+
+#                 |                    + $h3             H3 |
+#                 |                   / \                   |
+#                 |                  /   \                  |
+#                 |         $h3.111 +     + $h3.222         |
+#                 |  192.0.2.34/28          192.0.2.66/28   |
+#                 +-----------------------------------------+
+
+ALL_TESTS="
+	ping_ipv4
+	test_ets_strict
+"
+
+lib_dir=$(dirname $0)/../../../net/forwarding
+
+NUM_NETIFS=6
+source $lib_dir/lib.sh
+source $lib_dir/devlink_lib.sh
+source qos_lib.sh
+
+h1_create()
+{
+	simple_if_init $h1
+	mtu_set $h1 10000
+
+	vlan_create $h1 111 v$h1 192.0.2.33/28
+	ip link set dev $h1.111 type vlan egress-qos-map 0:1
+}
+
+h1_destroy()
+{
+	vlan_destroy $h1 111
+
+	mtu_restore $h1
+	simple_if_fini $h1
+}
+
+h2_create()
+{
+	simple_if_init $h2
+	mtu_set $h2 10000
+
+	vlan_create $h2 222 v$h2 192.0.2.65/28
+	ip link set dev $h2.222 type vlan egress-qos-map 0:2
+}
+
+h2_destroy()
+{
+	vlan_destroy $h2 222
+
+	mtu_restore $h2
+	simple_if_fini $h2
+}
+
+h3_create()
+{
+	simple_if_init $h3
+	mtu_set $h3 10000
+
+	vlan_create $h3 111 v$h3 192.0.2.34/28
+	vlan_create $h3 222 v$h3 192.0.2.66/28
+}
+
+h3_destroy()
+{
+	vlan_destroy $h3 222
+	vlan_destroy $h3 111
+
+	mtu_restore $h3
+	simple_if_fini $h3
+}
+
+switch_create()
+{
+	ip link set dev $swp1 up
+	mtu_set $swp1 10000
+
+	ip link set dev $swp2 up
+	mtu_set $swp2 10000
+
+	# prio n -> TC n, strict scheduling
+	lldptool -T -i $swp3 -V ETS-CFG up2tc=0:0,1:1,2:2,3:3,4:4,5:5,6:6,7:7
+	lldptool -T -i $swp3 -V ETS-CFG tsa=$(
+			)"0:strict,"$(
+			)"1:strict,"$(
+			)"2:strict,"$(
+			)"3:strict,"$(
+			)"4:strict,"$(
+			)"5:strict,"$(
+			)"6:strict,"$(
+			)"7:strict"
+	sleep 1
+
+	ip link set dev $swp3 up
+	mtu_set $swp3 10000
+	ethtool -s $swp3 speed 1000 autoneg off
+
+	vlan_create $swp1 111
+	vlan_create $swp2 222
+	vlan_create $swp3 111
+	vlan_create $swp3 222
+
+	ip link add name br111 up type bridge vlan_filtering 0
+	ip link set dev $swp1.111 master br111
+	ip link set dev $swp3.111 master br111
+
+	ip link add name br222 up type bridge vlan_filtering 0
+	ip link set dev $swp2.222 master br222
+	ip link set dev $swp3.222 master br222
+
+	# Make sure that ingress quotas are smaller than egress so that there is
+	# room for both streams of traffic to be admitted to shared buffer.
+	devlink_pool_size_thtype_set 0 dynamic 10000000
+	devlink_pool_size_thtype_set 4 dynamic 10000000
+
+	devlink_port_pool_th_set $swp1 0 6
+	devlink_tc_bind_pool_th_set $swp1 1 ingress 0 6
+
+	devlink_port_pool_th_set $swp2 0 6
+	devlink_tc_bind_pool_th_set $swp2 2 ingress 0 6
+
+	devlink_tc_bind_pool_th_set $swp3 1 egress 4 7
+	devlink_tc_bind_pool_th_set $swp3 2 egress 4 7
+	devlink_port_pool_th_set $swp3 4 7
+}
+
+switch_destroy()
+{
+	devlink_port_pool_th_restore $swp3 4
+	devlink_tc_bind_pool_th_restore $swp3 2 egress
+	devlink_tc_bind_pool_th_restore $swp3 1 egress
+
+	devlink_tc_bind_pool_th_restore $swp2 2 ingress
+	devlink_port_pool_th_restore $swp2 0
+
+	devlink_tc_bind_pool_th_restore $swp1 1 ingress
+	devlink_port_pool_th_restore $swp1 0
+
+	devlink_pool_size_thtype_restore 4
+	devlink_pool_size_thtype_restore 0
+
+	ip link del dev br222
+	ip link del dev br111
+
+	vlan_destroy $swp3 222
+	vlan_destroy $swp3 111
+	vlan_destroy $swp2 222
+	vlan_destroy $swp1 111
+
+	ethtool -s $swp3 autoneg on
+	mtu_restore $swp3
+	ip link set dev $swp3 down
+	lldptool -T -i $swp3 -V ETS-CFG up2tc=0:0,1:0,2:0,3:0,4:0,5:0,6:0,7:0
+
+	mtu_restore $swp2
+	ip link set dev $swp2 down
+
+	mtu_restore $swp1
+	ip link set dev $swp1 down
+}
+
+setup_prepare()
+{
+	h1=${NETIFS[p1]}
+	swp1=${NETIFS[p2]}
+
+	swp2=${NETIFS[p3]}
+	h2=${NETIFS[p4]}
+
+	swp3=${NETIFS[p5]}
+	h3=${NETIFS[p6]}
+
+	h3mac=$(mac_get $h3)
+
+	vrf_prepare
+
+	h1_create
+	h2_create
+	h3_create
+	switch_create
+}
+
+cleanup()
+{
+	pre_cleanup
+
+	switch_destroy
+	h3_destroy
+	h2_destroy
+	h1_destroy
+
+	vrf_cleanup
+}
+
+ping_ipv4()
+{
+	ping_test $h1 192.0.2.34 " from H1"
+	ping_test $h2 192.0.2.66 " from H2"
+}
+
+rel()
+{
+	local old=$1; shift
+	local new=$1; shift
+
+	bc <<< "
+	    scale=2
+	    ret = 100 * $new / $old
+	    if (ret > 0) { ret } else { 0 }
+	"
+}
+
+test_ets_strict()
+{
+	RET=0
+
+	# Run high-prio traffic on its own.
+	start_traffic $h2.222 192.0.2.65 192.0.2.66 $h3mac
+	local -a rate_2
+	rate_2=($(measure_rate $swp2 $h3 rx_octets_prio_2 "prio 2"))
+	check_err $? "Could not get high enough prio-2 ingress rate"
+	local rate_2_in=${rate_2[0]}
+	local rate_2_eg=${rate_2[1]}
+	stop_traffic # $h2.222
+
+	# Start low-prio stream.
+	start_traffic $h1.111 192.0.2.33 192.0.2.34 $h3mac
+
+	local -a rate_1
+	rate_1=($(measure_rate $swp1 $h3 rx_octets_prio_1 "prio 1"))
+	check_err $? "Could not get high enough prio-1 ingress rate"
+	local rate_1_in=${rate_1[0]}
+	local rate_1_eg=${rate_1[1]}
+
+	# High-prio and low-prio on their own should have about the same
+	# throughput.
+	local rel21=$(rel $rate_1_eg $rate_2_eg)
+	check_err $(bc <<< "$rel21 < 95")
+	check_err $(bc <<< "$rel21 > 105")
+
+	# Start the high-prio stream--now both streams run.
+	start_traffic $h2.222 192.0.2.65 192.0.2.66 $h3mac
+	rate_3=($(measure_rate $swp2 $h3 rx_octets_prio_2 "prio 2 w/ 1"))
+	check_err $? "Could not get high enough prio-2 ingress rate with prio-1"
+	local rate_3_in=${rate_3[0]}
+	local rate_3_eg=${rate_3[1]}
+	stop_traffic # $h2.222
+
+	stop_traffic # $h1.111
+
+	# High-prio should have about the same throughput whether or not
+	# low-prio is in the system.
+	local rel32=$(rel $rate_2_eg $rate_3_eg)
+	check_err $(bc <<< "$rel32 < 95")
+
+	log_test "strict priority"
+	echo "Ingress to switch:"
+	echo "  p1 in rate            $(humanize $rate_1_in)"
+	echo "  p2 in rate            $(humanize $rate_2_in)"
+	echo "  p2 in rate w/ p1      $(humanize $rate_3_in)"
+	echo "Egress from switch:"
+	echo "  p1 eg rate            $(humanize $rate_1_eg)"
+	echo "  p2 eg rate            $(humanize $rate_2_eg) ($rel21% of p1)"
+	echo "  p2 eg rate w/ p1      $(humanize $rate_3_eg) ($rel32% of p2)"
+}
+
+trap cleanup EXIT
+
+setup_prepare
+setup_wait
+
+tests_run
+
+exit $EXIT_STATUS