Only lock thread during RunThread if it's not already owned by the thread

thread.go

@@ -367,7 +367,17 @@ func RunThread(ctx * GraphContext, thread Thread) error {
   ctx.Log.Logf("thread", "THREAD_RUN: %s", thread.ID())
 
   err := UpdateStates(ctx, []GraphNode{thread}, func(nodes NodeMap) (error) {
-    return LockLockables(ctx, []Lockable{thread}, thread, nil, nodes)
+    thread_state := thread.State().(ThreadState)
+    owner_id := NodeID("")
+    if thread_state.Owner() != nil {
+      owner_id = thread_state.Owner().ID()
+    }
+
+    if owner_id != thread.ID() {
+      return LockLockables(ctx, []Lockable{thread}, thread, nil, nodes)
+    } else {
+      return nil
+    }
   })
   if err != nil {
     return err