--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/hotspot/src/share/vm/gc/g1/concurrentG1RefineThread.hpp	Wed May 13 15:16:06 2015 +0200
@@ -0,0 +1,89 @@
+/*
+ * Copyright (c) 2001, 2015, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ *
+ */
+
+#ifndef SHARE_VM_GC_G1_CONCURRENTG1REFINETHREAD_HPP
+#define SHARE_VM_GC_G1_CONCURRENTG1REFINETHREAD_HPP
+
+#include "gc/shared/concurrentGCThread.hpp"
+
+// Forward Decl.
+class CardTableEntryClosure;
+class ConcurrentG1Refine;
+
+// The G1 Concurrent Refinement Thread (could be several in the future).
+
+class ConcurrentG1RefineThread: public ConcurrentGCThread {
+  friend class VMStructs;
+  friend class G1CollectedHeap;
+
+  double _vtime_start;  // Initial virtual time.
+  double _vtime_accum;  // Initial virtual time.
+  uint _worker_id;
+  uint _worker_id_offset;
+
+  // The refinement threads collection is linked list. A predecessor can activate a successor
+  // when the number of the rset update buffer crosses a certain threshold. A successor
+  // would self-deactivate when the number of the buffers falls below the threshold.
+  bool _active;
+  ConcurrentG1RefineThread* _next;
+  Monitor* _monitor;
+  ConcurrentG1Refine* _cg1r;
+
+  // The closure applied to completed log buffers.
+  CardTableEntryClosure* _refine_closure;
+
+  int _thread_threshold_step;
+  // This thread activation threshold
+  int _threshold;
+  // This thread deactivation threshold
+  int _deactivation_threshold;
+
+  void sample_young_list_rs_lengths();
+  void run_young_rs_sampling();
+  void wait_for_completed_buffers();
+
+  void set_active(bool x) { _active = x; }
+  bool is_active();
+  void activate();
+  void deactivate();
+
+public:
+  virtual void run();
+  // Constructor
+  ConcurrentG1RefineThread(ConcurrentG1Refine* cg1r, ConcurrentG1RefineThread* next,
+                           CardTableEntryClosure* refine_closure,
+                           uint worker_id_offset, uint worker_id);
+
+  void initialize();
+
+  // Total virtual time so far.
+  double vtime_accum() { return _vtime_accum; }
+
+  ConcurrentG1Refine* cg1r() { return _cg1r;     }
+
+  // shutdown
+  void stop();
+};
+
+#endif // SHARE_VM_GC_G1_CONCURRENTG1REFINETHREAD_HPP