[PATCH net-next v9 2/3] selftests: tc-testing: add fq_pie per-flow class stats test

["Hemendra M. Naik" <hemendranaik@gmail.com>]

Add tc-testing case 83c0: build a TBF + fq_pie hierarchy on $DUMMY, push
traffic through it with ping, and verify that 'tc -s class show' reports
an fq_pie class.

The per-flow counters themselves (prob, delay, deficit) are printed with
the companion iproute2 change, "tc: fq_pie: add support for printing
per-flow PIE statistics"

Signed-off-by: Hemendra M. Naik <hemendranaik@gmail.com>
Signed-off-by: Vishal Kamath <vishy0777@gmail.com>
Signed-off-by: Mohit P. Tahiliani <tahiliani@nitk.edu.in>
---
 .../tc-testing/tc-tests/qdiscs/fq_pie.json    | 27 +++++++++++++++++++
 1 file changed, 27 insertions(+)

diff --git a/tools/testing/selftests/tc-testing/tc-tests/qdiscs/fq_pie.json b/tools/testing/selftests/tc-testing/tc-tests/qdiscs/fq_pie.json
index 229fe1bf4a90..15b2667285eb 100644
--- a/tools/testing/selftests/tc-testing/tc-tests/qdiscs/fq_pie.json
+++ b/tools/testing/selftests/tc-testing/tc-tests/qdiscs/fq_pie.json
@@ -40,5 +40,32 @@
         "matchPattern": "qdisc fq_pie 1: root refcnt [0-9]+ limit 1p",
         "matchCount": "1",
         "teardown": ["$TC qdisc del dev $DEV1 handle 1: root"]
+    },
+    {
+        "id": "83c0",
+        "name": "FQ-PIE class stats accessible via tc class show",
+        "category": [
+            "qdisc",
+            "fq_pie"
+        ],
+        "plugins": {
+            "requires": "nsPlugin"
+        },
+        "setup": [
+            "$IP link set dev $DUMMY up || true",
+            "$IP addr add 10.10.11.10/24 dev $DUMMY || true",
+            "$TC qdisc add dev $DUMMY root handle 1: tbf rate 8bit burst 100b latency 100ms",
+            "$TC qdisc add dev $DUMMY parent 1:1 handle 2: fq_pie limit 100 flows 1",
+            "ping -c 50 -i 0.001 -W 0.01 -s 56 10.10.11.11 -I $DUMMY > /dev/null 2>&1 || true"
+        ],
+        "cmdUnderTest": "$TC -s class show dev $DUMMY",
+        "expExitCode": "0",
+        "verifyCmd": "$TC -s class show dev $DUMMY",
+        "matchPattern": "class fq_pie 2:[0-9]+ .*prob .*delay .*deficit",
+        "matchCount": "1",
+        "teardown": [
+            "$TC qdisc del dev $DUMMY handle 1: root",
+            "$IP addr del 10.10.11.10/24 dev $DUMMY || true"
+        ]
     }
 ]
-- 
2.34.1