tetragon: Add overhead metrics test for tracepoint

Adding test for overhead metrics on top of tracepoint tracing policy.

Signed-off-by: Jiri Olsa <[email protected]>

pkg/sensors/tracing/tracepoint_test.go

@@ -869,3 +869,64 @@ spec:
 
 	testListSyscallsDupsRange(t, checker, configHook)
 }
+
+func TestTracepointOverheadStats(t *testing.T) {
+	var doneWG, readyWG sync.WaitGroup
+	defer doneWG.Wait()
+
+	ctx, cancel := context.WithTimeout(context.Background(), tus.Conf().CmdWaitTime)
+	defer cancel()
+
+	testNop := testutils.RepoRootPath("contrib/tester-progs/nop")
+
+	// enable bpf stats
+	stats, err := ebpf.EnableStats(uint32(unix.BPF_STATS_RUN_TIME))
+	if err != nil {
+		t.Fatalf("Failed to enable overhead stats: %s", err)
+	}
+	defer stats.Close()
+
+	tracingPolicy := `
+apiVersion: cilium.io/v1alpha1
+kind: TracingPolicy
+metadata:
+  name: "overhead"
+spec:
+  tracepoints:
+  - subsystem: "raw_syscalls"
+    event: "sys_enter"
+    args:
+    - index: 4
+      type: "syscall64"
+    - index: 5
+      type: "uint64"
+    selectors:
+    - matchBinaries:
+      - operator: "In"
+        values:
+        - "` + testNop + `"
+`
+	createCrdFile(t, tracingPolicy)
+
+	obs, err := observertesthelper.GetDefaultObserverWithFile(t, ctx, testConfigFile, tus.Conf().TetragonLib)
+	if err != nil {
+		t.Fatalf("GetDefaultObserverWithFile error: %s", err)
+	}
+	observertesthelper.LoopEvents(ctx, t, &doneWG, &readyWG, obs)
+	readyWG.Wait()
+
+	if err := exec.Command(testNop).Run(); err != nil {
+		fmt.Printf("Failed to execute test binary: %s\n", err)
+	}
+
+	res := []*metricResult{
+		{label: "attach=\"raw_syscalls/sys_enter\",policy=\"overhead\"", value: 1},
+		{label: "attach=\"acct_process\",policy=\"__base__\"", value: 1},
+		{label: "attach=\"sched/sched_process_exec\",policy=\"__base__\"", value: 1},
+		{label: "attach=\"security_bprm_committing_creds\",policy=\"__base__\"", value: 1},
+		{label: "attach=\"wake_up_new_task\",policy=\"__base__\"", value: 1},
+	}
+
+	checkMetric(t, "http://localhost:2112", "tetragon_overhead_cnt_program_total", res)
+	checkMetric(t, "http://localhost:2112", "tetragon_overhead_time_program_total", res)
+}