[PATCH net-next 5/5] selftests: forwarding: ETS: Use Qdisc counters

[Ido Schimmel <idosch@idosch.org>]

From: Petr Machata <petrm@mellanox.com>

Currently the SW-datapath ETS selftests use "ip link" stats to obtain the
number of packets that went through a given band. mlxsw then uses ethtool
per-priority counters.

Instead, change both to use qdiscs. In SW datapath this is the obvious
choice, and now that mlxsw offloads FIFO, this should work on the offloaded
datapath as well. This has the effect of verifying that the FIFO offload
works.

Signed-off-by: Petr Machata <petrm@mellanox.com>
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
---
 .../testing/selftests/drivers/net/mlxsw/sch_ets.sh | 14 +++++++++++---
 tools/testing/selftests/net/forwarding/lib.sh      | 10 ++++++++++
 tools/testing/selftests/net/forwarding/sch_ets.sh  |  9 ++++++---
 .../selftests/net/forwarding/sch_ets_tests.sh      | 10 +++-------
 4 files changed, 30 insertions(+), 13 deletions(-)

diff --git a/tools/testing/selftests/drivers/net/mlxsw/sch_ets.sh b/tools/testing/selftests/drivers/net/mlxsw/sch_ets.sh
index c9fc4d4885c1..94c37124a840 100755
--- a/tools/testing/selftests/drivers/net/mlxsw/sch_ets.sh
+++ b/tools/testing/selftests/drivers/net/mlxsw/sch_ets.sh
@@ -56,11 +56,19 @@ switch_destroy()
 }
 
 # Callback from sch_ets_tests.sh
-get_stats()
+collect_stats()
 {
-	local band=$1; shift
+	local -a streams=("$@")
+	local stream
 
-	ethtool_stats_get "$h2" rx_octets_prio_$band
+	# Wait for qdisc counter update so that we don't get it mid-way through.
+	busywait_for_counter 1000 +1 \
+		qdisc_parent_stats_get $swp2 10:$((${streams[0]} + 1)) .bytes \
+		> /dev/null
+
+	for stream in ${streams[@]}; do
+		qdisc_parent_stats_get $swp2 10:$((stream + 1)) .bytes
+	done
 }
 
 bail_on_lldpad
diff --git a/tools/testing/selftests/net/forwarding/lib.sh b/tools/testing/selftests/net/forwarding/lib.sh
index 7ecce65d08f9..a4a7879b3bb9 100644
--- a/tools/testing/selftests/net/forwarding/lib.sh
+++ b/tools/testing/selftests/net/forwarding/lib.sh
@@ -655,6 +655,16 @@ qdisc_stats_get()
 	    | jq '.[] | select(.handle == "'"$handle"'") | '"$selector"
 }
 
+qdisc_parent_stats_get()
+{
+	local dev=$1; shift
+	local parent=$1; shift
+	local selector=$1; shift
+
+	tc -j -s qdisc show dev "$dev" invisible \
+	    | jq '.[] | select(.parent == "'"$parent"'") | '"$selector"
+}
+
 humanize()
 {
 	local speed=$1; shift
diff --git a/tools/testing/selftests/net/forwarding/sch_ets.sh b/tools/testing/selftests/net/forwarding/sch_ets.sh
index 40e0ad1bc4f2..e60c8b4818cc 100755
--- a/tools/testing/selftests/net/forwarding/sch_ets.sh
+++ b/tools/testing/selftests/net/forwarding/sch_ets.sh
@@ -34,11 +34,14 @@ switch_destroy()
 }
 
 # Callback from sch_ets_tests.sh
-get_stats()
+collect_stats()
 {
-	local stream=$1; shift
+	local -a streams=("$@")
+	local stream
 
-	link_stats_get $h2.1$stream rx bytes
+	for stream in ${streams[@]}; do
+		qdisc_parent_stats_get $swp2 10:$((stream + 1)) .bytes
+	done
 }
 
 ets_run
diff --git a/tools/testing/selftests/net/forwarding/sch_ets_tests.sh b/tools/testing/selftests/net/forwarding/sch_ets_tests.sh
index 3c3b204d47e8..cdf689e99458 100644
--- a/tools/testing/selftests/net/forwarding/sch_ets_tests.sh
+++ b/tools/testing/selftests/net/forwarding/sch_ets_tests.sh
@@ -2,7 +2,7 @@
 
 # Global interface:
 #  $put -- port under test (e.g. $swp2)
-#  get_stats($band) -- A function to collect stats for band
+#  collect_stats($streams...) -- A function to get stats for individual streams
 #  ets_start_traffic($band) -- Start traffic for this band
 #  ets_change_qdisc($op, $dev, $nstrict, $quanta...) -- Add or change qdisc
 
@@ -94,15 +94,11 @@ __ets_dwrr_test()
 
 	sleep 10
 
-	t0=($(for stream in ${streams[@]}; do
-		  get_stats $stream
-	      done))
+	t0=($(collect_stats "${streams[@]}"))
 
 	sleep 10
 
-	t1=($(for stream in ${streams[@]}; do
-		  get_stats $stream
-	      done))
+	t1=($(collect_stats "${streams[@]}"))
 	d=($(for ((i = 0; i < ${#streams[@]}; i++)); do
 		 echo $((${t1[$i]} - ${t0[$i]}))
 	     done))
-- 
2.24.1