new file mode 100755
@@ -0,0 +1,249 @@
+#!/bin/bash
+# SPDX-License-Identifier: GPL-2.0
+
+# Test for DSCP prioritization and rewrite. Packets ingress $swp1 with a DSCP
+# tag and are prioritized according to the map at $swp1. They egress $swp2 and
+# the DSCP value is updated to match the map at that interface. The updated DSCP
+# tag is verified at $h2.
+#
+# ICMP responses are produced with the same DSCP tag that arrived at $h2. They
+# go through prioritization at $swp2 and DSCP retagging at $swp1. The tag is
+# verified at $h1--it should match the original tag.
+#
+# +----------------------+ +----------------------+
+# | H1 | | H2 |
+# | + $h1 | | $h2 + |
+# | | 192.0.2.1/28 | | 192.0.2.2/28 | |
+# +----|-----------------+ +----------------|-----+
+# | |
+# +----|----------------------------------------------------------------|-----+
+# | SW | | |
+# | +-|----------------------------------------------------------------|-+ |
+# | | + $swp1 BR $swp2 + | |
+# | | APP=0,5,10 .. 7,5,17 APP=0,5,20 .. 7,5,27 | |
+# | +--------------------------------------------------------------------+ |
+# +---------------------------------------------------------------------------+
+
+ALL_TESTS="
+ ping_ipv4
+ test_dscp
+"
+
+lib_dir=$(dirname $0)/../../../net/forwarding
+
+NUM_NETIFS=4
+source $lib_dir/lib.sh
+
+__dscp_capture_add_del()
+{
+ local add_del=$1; shift
+ local dev=$1; shift
+ local base=$1; shift
+ local dscp;
+
+ for prio in {0..7}; do
+ dscp=$((base + prio))
+ __icmp_capture_add_del $add_del $dscp "" $dev \
+ "ip_tos $((dscp << 2))"
+ done
+}
+
+dscp_capture_install()
+{
+ local dev=$1; shift
+ local base=$1; shift
+
+ __dscp_capture_add_del add $dev $base
+}
+
+dscp_capture_uninstall()
+{
+ local dev=$1; shift
+ local base=$1; shift
+
+ __dscp_capture_add_del del $dev $base
+}
+
+h1_create()
+{
+ local dscp;
+
+ simple_if_init $h1 192.0.2.1/28
+ tc qdisc add dev $h1 clsact
+ dscp_capture_install $h1 10
+}
+
+h1_destroy()
+{
+ dscp_capture_uninstall $h1 10
+ simple_if_fini $h1 192.0.2.1/28
+ tc qdisc del dev $h1 clsact
+}
+
+h2_create()
+{
+ simple_if_init $h2 192.0.2.2/28
+ tc qdisc add dev $h2 clsact
+ dscp_capture_install $h2 20
+}
+
+h2_destroy()
+{
+ dscp_capture_uninstall $h2 20
+ simple_if_fini $h2 192.0.2.2/28
+ tc qdisc del dev $h2 clsact
+}
+
+dscp_map()
+{
+ local base=$1; shift
+
+ for prio in {0..7}; do
+ echo app=$prio,5,$((base + prio))
+ done
+}
+
+lldpad_wait()
+{
+ local dev=$1; shift
+
+ while lldptool -t -i $dev -V APP -c app | grep -q pending; do
+ echo "$dev: waiting for lldpad to push pending APP updates"
+ sleep 5
+ done
+}
+
+switch_create()
+{
+ ip link add name br1 type bridge vlan_filtering 1
+ ip link set dev br1 up
+ ip link set dev $swp1 master br1
+ ip link set dev $swp1 up
+ ip link set dev $swp2 master br1
+ ip link set dev $swp2 up
+
+ lldptool -T -i $swp1 -V APP $(dscp_map 10) >/dev/null
+ lldptool -T -i $swp2 -V APP $(dscp_map 20) >/dev/null
+ lldpad_wait $swp1
+ lldpad_wait $swp2
+}
+
+switch_destroy()
+{
+ lldptool -T -i $swp2 -V APP -d $(dscp_map 20) >/dev/null
+ lldptool -T -i $swp1 -V APP -d $(dscp_map 10) >/dev/null
+
+ # Give lldpad a chance to push down the changes. If the device is downed
+ # too soon, the updates will be left pending, but will have been struck
+ # off the lldpad's DB already, and we won't be able to tell. Then on
+ # next test iteration this would cause weirdness as newly-added APP
+ # rules conflict with the old ones, sometimes getting stuck in an
+ # "unknown" state.
+ sleep 5
+
+ ip link set dev $swp2 nomaster
+ ip link set dev $swp1 nomaster
+ ip link del dev br1
+}
+
+setup_prepare()
+{
+ h1=${NETIFS[p1]}
+ swp1=${NETIFS[p2]}
+
+ swp2=${NETIFS[p3]}
+ h2=${NETIFS[p4]}
+
+ vrf_prepare
+
+ h1_create
+ h2_create
+ switch_create
+}
+
+cleanup()
+{
+ pre_cleanup
+
+ switch_destroy
+ h2_destroy
+ h1_destroy
+
+ vrf_cleanup
+}
+
+dscp_fetch_stats()
+{
+ local dev=$1; shift
+ local base=$1; shift
+
+ for prio in {0..7}; do
+ local dscp=$((base + prio))
+ local t=$(tc_rule_stats_get $dev $dscp)
+ echo "[$dscp]=$t "
+ done
+}
+
+ping_ipv4()
+{
+ ping_test $h1 192.0.2.2
+}
+
+dscp_ping_test()
+{
+ local vrf_name=$1; shift
+ local sip=$1; shift
+ local dip=$1; shift
+ local prio=$1; shift
+ local dev_10=$1; shift
+ local dev_20=$1; shift
+
+ local dscp_10=$(((prio + 10) << 2))
+ local dscp_20=$(((prio + 20) << 2))
+
+ RET=0
+
+ local -A t0s
+ eval "t0s=($(dscp_fetch_stats $dev_10 10)
+ $(dscp_fetch_stats $dev_20 20))"
+
+ ip vrf exec $vrf_name \
+ ${PING} -Q $dscp_10 ${sip:+-I $sip} $dip \
+ -c 10 -i 0.1 -w 2 &> /dev/null
+
+ local -A t1s
+ eval "t1s=($(dscp_fetch_stats $dev_10 10)
+ $(dscp_fetch_stats $dev_20 20))"
+
+ for key in ${!t0s[@]}; do
+ local expect
+ if ((key == dscp_10 || key == dscp_20)); then
+ expect=10
+ else
+ expect=0
+ fi
+
+ # Tolerate a couple stray extra packets.
+ local delta=$((t1s[key] - t0s[key]))
+ ((expect <= delta && delta <= expect + 2))
+ check_err $? "DSCP $key: Expected to capture $expect packets, got $delta."
+ done
+
+ log_test "DSCP rewrite: $dscp_10-(prio $prio)-$dscp_20"
+}
+
+test_dscp()
+{
+ for prio in {0..7}; do
+ dscp_ping_test v$h1 192.0.2.1 192.0.2.2 $prio $h1 $h2
+ done
+}
+
+trap cleanup EXIT
+
+setup_prepare
+setup_wait
+
+tests_run
+
+exit $EXIT_STATUS
Add a test that exercises the new code. Send DSCP-tagged packets, and observe how they are prioritized in the switch and the DSCP is updated on egress again. Signed-off-by: Petr Machata <petrm@mellanox.com> --- .../selftests/drivers/net/mlxsw/qos_dscp.sh | 249 +++++++++++++++++++++ 1 file changed, 249 insertions(+) create mode 100755 tools/testing/selftests/drivers/net/mlxsw/qos_dscp.sh