[#1700] engine: Print stacks on test request limiter

Change-Id: I4952769ca431d1049955823b41b99b0984b385fc
Signed-off-by: Dmitrii Stepanov <d.stepanov@yadro.com>

pkg/local_object_storage/engine/engine_test.go

@@ -2,8 +2,11 @@ package engine
 
 import (
 	"context"
+	"fmt"
 	"path/filepath"
-	"sync/atomic"
+	"runtime/debug"
+	"strings"
+	"sync"
 	"testing"
 
 	"git.frostfs.info/TrueCloudLab/frostfs-node/internal/qos"
@@ -157,26 +160,74 @@ func newTestStorages(root string, smallSize uint64) ([]blobstor.SubStorage, *tes
 var _ qos.Limiter = (*testQoSLimiter)(nil)
 
 type testQoSLimiter struct {
-	t     testing.TB
-	read  atomic.Int64
-	write atomic.Int64
+	t           testing.TB
+	quard       sync.Mutex
+	id          int64
+	readStacks  map[int64][]byte
+	writeStacks map[int64][]byte
 }
 
 func (t *testQoSLimiter) SetMetrics(qos.Metrics) {}
 
 func (t *testQoSLimiter) Close() {
-	require.Equal(t.t, int64(0), t.read.Load(), "read requests count after limiter close must be 0")
-	require.Equal(t.t, int64(0), t.write.Load(), "write requests count after limiter close must be 0")
+	t.quard.Lock()
+	defer t.quard.Unlock()
+
+	var sb strings.Builder
+	var seqN int
+	for _, stack := range t.readStacks {
+		seqN++
+		sb.WriteString(fmt.Sprintf("%d\n read request stack after limiter close: %s\n", seqN, string(stack)))
+	}
+	for _, stack := range t.writeStacks {
+		seqN++
+		sb.WriteString(fmt.Sprintf("%d\n write request stack after limiter close: %s\n", seqN, string(stack)))
+	}
+	require.True(t.t, seqN == 0, sb.String())
 }
 
 func (t *testQoSLimiter) ReadRequest(context.Context) (qos.ReleaseFunc, error) {
-	t.read.Add(1)
-	return func() { t.read.Add(-1) }, nil
+	t.quard.Lock()
+	defer t.quard.Unlock()
+
+	stack := debug.Stack()
+
+	t.id++
+	id := t.id
+
+	if t.readStacks == nil {
+		t.readStacks = make(map[int64][]byte)
+	}
+	t.readStacks[id] = stack
+
+	return func() {
+		t.quard.Lock()
+		defer t.quard.Unlock()
+
+		delete(t.readStacks, id)
+	}, nil
 }
 
 func (t *testQoSLimiter) WriteRequest(context.Context) (qos.ReleaseFunc, error) {
-	t.write.Add(1)
-	return func() { t.write.Add(-1) }, nil
+	t.quard.Lock()
+	defer t.quard.Unlock()
+
+	stack := debug.Stack()
+
+	t.id++
+	id := t.id
+
+	if t.writeStacks == nil {
+		t.writeStacks = make(map[int64][]byte)
+	}
+	t.writeStacks[id] = stack
+
+	return func() {
+		t.quard.Lock()
+		defer t.quard.Unlock()
+
+		delete(t.writeStacks, id)
+	}, nil
 }
 
 func (t *testQoSLimiter) SetParentID(string) {}