[#xx] shard: Fix data race in metrics tests

Protect test metric store fields with a mutex. Probably, not every field
should be protected, but better safe than sorry.

Signed-off-by: Evgenii Stratonikov <e.stratonikov@yadro.com>

pkg/local_object_storage/shard/metrics_test.go

@@ -3,6 +3,7 @@ package shard_test
 import (
 	"context"
 	"path/filepath"
+	"sync"
 	"testing"
 
 	objectcore "git.frostfs.info/TrueCloudLab/frostfs-node/pkg/core/object"
@@ -19,6 +20,7 @@ import (
 )
 
 type metricsStore struct {
+	mtx         sync.Mutex
 	objCounters map[string]uint64
 	cnrSize     map[string]int64
 	pldSize     int64
@@ -49,35 +51,51 @@ func (m metricsStore) AddToObjectCounter(objectType string, delta int) {
 	}
 }
 
-func (m metricsStore) IncObjectCounter(objectType string) {
+func (m *metricsStore) IncObjectCounter(objectType string) {
+	m.mtx.Lock()
+	defer m.mtx.Unlock()
 	m.objCounters[objectType] += 1
 }
 
-func (m metricsStore) DecObjectCounter(objectType string) {
+func (m *metricsStore) DecObjectCounter(objectType string) {
+	m.mtx.Lock()
+	defer m.mtx.Unlock()
 	m.AddToObjectCounter(objectType, -1)
 }
 
 func (m *metricsStore) SetMode(mode mode.Mode) {
+	m.mtx.Lock()
+	defer m.mtx.Unlock()
 	m.mode = mode
 }
 
-func (m metricsStore) AddToContainerSize(cnr string, size int64) {
+func (m *metricsStore) AddToContainerSize(cnr string, size int64) {
+	m.mtx.Lock()
+	defer m.mtx.Unlock()
 	m.cnrSize[cnr] += size
 }
 
 func (m *metricsStore) AddToPayloadSize(size int64) {
+	m.mtx.Lock()
+	defer m.mtx.Unlock()
 	m.pldSize += size
 }
 
 func (m *metricsStore) IncErrorCounter() {
+	m.mtx.Lock()
+	defer m.mtx.Unlock()
 	m.errCounter += 1
 }
 
 func (m *metricsStore) ClearErrorCounter() {
+	m.mtx.Lock()
+	defer m.mtx.Unlock()
 	m.errCounter = 0
 }
 
 func (m *metricsStore) DeleteShardMetrics() {
+	m.mtx.Lock()
+	defer m.mtx.Unlock()
 	m.errCounter = 0
 }