Move metrics to core/metrics

Signed-off-by: Derek McGowan <derek@mcg.dev>

core/metrics/cgroups/metrics_test.go

@@ -0,0 +1,157 @@
+//go:build linux
+
+/*
+   Copyright The containerd Authors.
+
+   Licensed under the Apache License, Version 2.0 (the "License");
+   you may not use this file except in compliance with the License.
+   You may obtain a copy of the License at
+
+       http://www.apache.org/licenses/LICENSE-2.0
+
+   Unless required by applicable law or agreed to in writing, software
+   distributed under the License is distributed on an "AS IS" BASIS,
+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+   See the License for the specific language governing permissions and
+   limitations under the License.
+*/
+
+package cgroups
+
+import (
+	"context"
+	"strconv"
+	"sync"
+	"testing"
+	"time"
+
+	"github.com/containerd/cgroups/v3"
+	"github.com/containerd/containerd/v2/core/metrics/cgroups/common"
+	v1 "github.com/containerd/containerd/v2/core/metrics/cgroups/v1"
+	v2 "github.com/containerd/containerd/v2/core/metrics/cgroups/v2"
+	v1types "github.com/containerd/containerd/v2/core/metrics/types/v1"
+	v2types "github.com/containerd/containerd/v2/core/metrics/types/v2"
+	"github.com/containerd/containerd/v2/protobuf"
+	"github.com/prometheus/client_golang/prometheus"
+
+	"github.com/containerd/containerd/v2/protobuf/types"
+	metrics "github.com/docker/go-metrics"
+)
+
+// TestRegressionIssue6772 should not have dead-lock when Collect and Add run
+// in the same time.
+//
+// Issue: https://github.com/containerd/containerd/issues/6772.
+func TestRegressionIssue6772(t *testing.T) {
+	ns := metrics.NewNamespace("test-container", "", nil)
+	isV1 := true
+
+	var collecter Collecter
+	if cgroups.Mode() == cgroups.Unified {
+		isV1 = false
+		collecter = v2.NewCollector(ns)
+	} else {
+		collecter = v1.NewCollector(ns)
+	}
+
+	doneCh := make(chan struct{})
+	defer close(doneCh)
+
+	maxItem := 100
+	startCh := make(chan struct{})
+
+	metricCh := make(chan prometheus.Metric, maxItem)
+
+	go func() {
+		for {
+			select {
+			case <-doneCh:
+				return
+			case <-metricCh:
+			}
+		}
+	}()
+
+	go func() {
+		// pulling the metrics to trigger dead-lock
+		ns.Collect(metricCh)
+		close(startCh)
+
+		for {
+			select {
+			case <-doneCh:
+				return
+			default:
+			}
+
+			ns.Collect(metricCh)
+		}
+	}()
+	<-startCh
+
+	labels := map[string]string{"issue": "6772"}
+	errCh := make(chan error, 1)
+
+	var wg sync.WaitGroup
+	for i := 0; i < maxItem; i++ {
+		id := i
+		wg.Add(1)
+
+		go func() {
+			defer wg.Done()
+
+			err := collecter.Add(
+				&mockStatT{
+					id:        strconv.Itoa(id),
+					namespace: "issue6772",
+					isV1:      isV1,
+				},
+				labels,
+			)
+			if err != nil {
+				errCh <- err
+			}
+		}()
+	}
+
+	finishedCh := make(chan struct{})
+	go func() {
+		defer close(finishedCh)
+
+		wg.Wait()
+	}()
+
+	select {
+	case err := <-errCh:
+		t.Fatalf("unexpected error: %v", err)
+	case <-finishedCh:
+	case <-time.After(30 * time.Second):
+		t.Fatal("should finish the Add in time")
+	}
+}
+
+type Collecter interface {
+	Collect(ch chan<- prometheus.Metric)
+
+	Add(t common.Statable, labels map[string]string) error
+}
+
+type mockStatT struct {
+	id, namespace string
+	isV1          bool
+}
+
+func (t *mockStatT) ID() string {
+	return t.id
+}
+
+func (t *mockStatT) Namespace() string {
+	return t.namespace
+}
+
+func (t *mockStatT) Stats(context.Context) (*types.Any, error) {
+	if t.isV1 {
+		return protobuf.MarshalAnyToProto(&v1types.Metrics{})
+	}
+	return protobuf.MarshalAnyToProto(&v2types.Metrics{})
+}