src/hotspot/share/gc/z/zMark.cpp

concurrent root iterator

     // during mark.
     _mark->flush_and_free();
   }
 };
 
+class ZMarkConcurrentRootsTask : public ZTask {
+private:
+  ZMark* const             _mark;
+  ZConcurrentRootsIterator _roots;
+
+public:
+  ZMarkConcurrentRootsTask(ZMark* mark) :
+      ZTask("ZMarkConcurrentRootsTask"),
+      _mark(mark),
+      _roots() {}
+
+  virtual void work() {
+    ZMarkBarrierOopClosure</* finalizable */ false> cl;
+    _roots.oops_do(&cl);
+  }
+};
+
+
 void ZMark::start() {
   // Verification
   if (ZVerifyMarking) {
     verify_all_stacks_empty();
   }

@@ -152,10 +170,15
   // Mark roots
   ZMarkRootsTask task(this);
   _workers->run_parallel(&task);
 }
 
+void ZMark::mark_concurrent_roots() {
+  ZMarkConcurrentRootsTask task(this);
+  _workers->run_concurrent(&task);
+}
+
 void ZMark::prepare_work() {
   assert(_nworkers == _workers->nconcurrent(), "Invalid number of workers");
 
   // Set number of active workers
   _terminate.reset(_nworkers);