X-Git-Url: https://git.arvados.org/arvados.git/blobdiff_plain/2e03d03bc55b5a612c2bf04d878a72f2ee420d99..095e176632bbf81d28a239742a1ecce12404bd2d:/sdk/go/arvados/fs_base.go

diff --git a/sdk/go/arvados/fs_base.go b/sdk/go/arvados/fs_base.go
index 2ad4d1f859..274d207022 100644
--- a/sdk/go/arvados/fs_base.go
+++ b/sdk/go/arvados/fs_base.go
@@ -420,10 +420,20 @@ func (n *treenode) Sync() error {
 }
 
 func (n *treenode) MemorySize() (size int64) {
+	// To avoid making other callers wait while we count the
+	// entire filesystem size, we lock the node only long enough
+	// to copy the list of children. We accept that the resulting
+	// size will sometimes be misleading (e.g., we will
+	// double-count an item that moves from A to B after we check
+	// A's size but before we check B's size).
 	n.RLock()
-	defer n.RUnlock()
 	debugPanicIfNotLocked(n, false)
+	todo := make([]inode, 0, len(n.inodes))
 	for _, inode := range n.inodes {
+		todo = append(todo, inode)
+	}
+	n.RUnlock()
+	for _, inode := range todo {
 		size += inode.MemorySize()
 	}
 	return 64 + size
@@ -631,7 +641,15 @@ func (fs *fileSystem) Rename(oldname, newname string) error {
 	}
 	locked := map[sync.Locker]bool{}
 	for i := len(needLock) - 1; i >= 0; i-- {
-		if n := needLock[i]; !locked[n] {
+		n := needLock[i]
+		if fs, ok := n.(interface{ rootnode() inode }); ok {
+			// Lock the fs's root dir directly, not
+			// through the fs. Otherwise our "locked" map
+			// would not reliably prevent double-locking
+			// the fs's root dir.
+			n = fs.rootnode()
+		}
+		if !locked[n] {
 			n.Lock()
 			defer n.Unlock()
 			locked[n] = true