[#373] blobovniczatree: Add metrics

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

pkg/local_object_storage/blobstor/blobovniczatree/control.go

@@ -13,6 +13,7 @@ import (
 // Open opens blobovnicza tree.
 func (b *Blobovniczas) Open(readOnly bool) error {
 	b.readOnly = readOnly
+	b.metrics.SetMode(readOnly)
 	return nil
 }
 
@@ -70,6 +71,7 @@ func (b *Blobovniczas) Close() error {
 	}
 
 	b.active = make(map[string]blobovniczaWithIndex)
+	b.metrics.Close()
 
 	b.lruMtx.Unlock()
 
@@ -123,9 +125,12 @@ func (b *Blobovniczas) openBlobovniczaNoCache(p string) (*blobovnicza.Blobovnicz
 	b.openMtx.Lock()
 	defer b.openMtx.Unlock()
 
+	path := filepath.Join(b.rootPath, p)
+
 	blz := blobovnicza.New(append(b.blzOpts,
 		blobovnicza.WithReadOnly(b.readOnly),
-		blobovnicza.WithPath(filepath.Join(b.rootPath, p)),
+		blobovnicza.WithPath(path),
+		blobovnicza.WithMetrics(b.metrics.BlobovnicaMetrics(path)),
 	)...)
 
 	if err := blz.Open(); err != nil {