selftests/tc-testing: add tests for qdisc_tree_reduce_backlog

Add 3 tests to check for the expected behaviour of
qdisc_tree_reduce_backlog in special scenarios.

- The first test checks if the qdisc class is notified of deletion for
major handle 'ffff:'.
- The second test checks the same as the first test but with 'ffff:' as the root
qdisc.
- The third test checks if everything works if ingress is active.

Acked-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: Pedro Tammela <pctammela@mojatatu.com>
Acked-by: Cong Wang <cong.wang@bytedance.com>
Link: https://patch.msgid.link/20241101143148.1218890-1-pctammela@mojatatu.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

1 files changed, 98 insertions, 0 deletions

diff --git a/tools/testing/selftests/tc-testing/tc-tests/infra/qdiscs.json b/tools/testing/selftests/tc-testing/tc-tests/infra/qdiscs.json
new file mode 100644
index 000000000000..d3dd65b05b5f
--- /dev/null
+++ b/tools/testing/selftests/tc-testing/tc-tests/infra/qdiscs.json
@@ -0,0 +1,98 @@
+[
+    {
+        "id": "ca5e",
+        "name": "Check class delete notification for ffff:",
+        "category": [
+            "qdisc"
+        ],
+        "plugins": {
+            "requires": "nsPlugin"
+        },
+        "setup": [
+            "$IP link set dev $DUMMY up || true",
+            "$IP addr add 10.10.10.10/24 dev $DUMMY || true",
+            "$TC qdisc add dev $DUMMY root handle 1: drr",
+            "$TC filter add dev $DUMMY parent 1: basic classid 1:1",
+            "$TC class add dev $DUMMY parent 1: classid 1:1 drr",
+            "$TC qdisc add dev $DUMMY parent 1:1 handle ffff: drr",
+            "$TC filter add dev $DUMMY parent ffff: basic classid ffff:1",
+            "$TC class add dev $DUMMY parent ffff: classid ffff:1 drr",
+            "$TC qdisc add dev $DUMMY parent ffff:1 netem delay 1s",
+            "ping -c1 -W0.01 -I $DUMMY 10.10.10.1 || true",
+            "$TC class del dev $DUMMY classid ffff:1",
+            "$TC class add dev $DUMMY parent ffff: classid ffff:1 drr"
+        ],
+        "cmdUnderTest": "ping -c1 -W0.01 -I $DUMMY 10.10.10.1",
+        "expExitCode": "1",
+        "verifyCmd": "$TC -s qdisc ls dev $DUMMY",
+        "matchPattern": "drr 1: root",
+        "matchCount": "1",
+        "teardown": [
+            "$TC qdisc del dev $DUMMY root handle 1: drr",
+            "$IP addr del 10.10.10.10/24 dev $DUMMY"
+        ]
+    },
+    {
+        "id": "e4b7",
+        "name": "Check class delete notification for root ffff:",
+        "category": [
+            "qdisc"
+        ],
+        "plugins": {
+            "requires": "nsPlugin"
+        },
+        "setup": [
+            "$IP link set dev $DUMMY up || true",
+            "$IP addr add 10.10.10.10/24 dev $DUMMY || true",
+            "$TC qdisc add dev $DUMMY root handle ffff: drr",
+            "$TC filter add dev $DUMMY parent ffff: basic classid ffff:1",
+            "$TC class add dev $DUMMY parent ffff: classid ffff:1 drr",
+            "$TC qdisc add dev $DUMMY parent ffff:1 netem delay 1s",
+            "ping -c1 -W0.01 -I $DUMMY 10.10.10.1 || true",
+            "$TC class del dev $DUMMY classid ffff:1",
+            "$TC class add dev $DUMMY parent ffff: classid ffff:1 drr"
+        ],
+        "cmdUnderTest": "ping -c1 -W0.01 -I $DUMMY 10.10.10.1",
+        "expExitCode": "1",
+        "verifyCmd": "$TC qdisc ls dev $DUMMY",
+        "matchPattern": "drr ffff: root",
+        "matchCount": "1",
+        "teardown": [
+            "$TC qdisc del dev $DUMMY root handle ffff: drr",
+            "$IP addr del 10.10.10.10/24 dev $DUMMY"
+        ]
+    },
+    {
+        "id": "33a9",
+        "name": "Check ingress is not searchable on backlog update",
+        "category": [
+            "qdisc"
+        ],
+        "plugins": {
+            "requires": "nsPlugin"
+        },
+        "setup": [
+            "$IP link set dev $DUMMY up || true",
+            "$IP addr add 10.10.10.10/24 dev $DUMMY || true",
+            "$TC qdisc add dev $DUMMY ingress",
+            "$TC qdisc add dev $DUMMY root handle 1: drr",
+            "$TC filter add dev $DUMMY parent 1: basic classid 1:1",
+            "$TC class add dev $DUMMY parent 1: classid 1:1 drr",
+            "$TC qdisc add dev $DUMMY parent 1:1 handle 2: drr",
+            "$TC filter add dev $DUMMY parent 2: basic classid 2:1",
+            "$TC class add dev $DUMMY parent 2: classid 2:1 drr",
+            "$TC qdisc add dev $DUMMY parent 2:1 netem delay 1s",
+            "ping -c1 -W0.01 -I $DUMMY 10.10.10.1 || true"
+        ],
+        "cmdUnderTest": "$TC class del dev $DUMMY classid 2:1",
+        "expExitCode": "0",
+        "verifyCmd": "$TC qdisc ls dev $DUMMY",
+        "matchPattern": "drr 1: root",
+        "matchCount": "1",
+        "teardown": [
+            "$TC qdisc del dev $DUMMY root handle 1: drr",
+            "$TC qdisc del dev $DUMMY ingress",
+            "$IP addr del 10.10.10.10/24 dev $DUMMY"
+        ]
+    }
+]