--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/hotspot/share/gc/g1/g1ConcurrentRefine.hpp	Mon Nov 06 14:24:31 2017 +0100
@@ -0,0 +1,107 @@
+/*
+ * Copyright (c) 2001, 2017, 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_G1CONCURRENTREFINE_HPP
+#define SHARE_VM_GC_G1_G1CONCURRENTREFINE_HPP
+
+#include "memory/allocation.hpp"
+#include "utilities/globalDefinitions.hpp"
+
+// Forward decl
+class CardTableEntryClosure;
+class G1ConcurrentRefineThread;
+class G1YoungRemSetSamplingThread;
+class outputStream;
+class ThreadClosure;
+
+class G1ConcurrentRefine : public CHeapObj<mtGC> {
+  G1YoungRemSetSamplingThread* _sample_thread;
+
+  G1ConcurrentRefineThread** _threads;
+  uint _n_worker_threads;
+ /*
+  * The value of the update buffer queue length falls into one of 3 zones:
+  * green, yellow, red. If the value is in [0, green) nothing is
+  * done, the buffers are left unprocessed to enable the caching effect of the
+  * dirtied cards. In the yellow zone [green, yellow) the concurrent refinement
+  * threads are gradually activated. In [yellow, red) all threads are
+  * running. If the length becomes red (max queue length) the mutators start
+  * processing the buffers.
+  *
+  * There are some interesting cases (when G1UseAdaptiveConcRefinement
+  * is turned off):
+  * 1) green = yellow = red = 0. In this case the mutator will process all
+  *    buffers. Except for those that are created by the deferred updates
+  *    machinery during a collection.
+  * 2) green = 0. Means no caching. Can be a good way to minimize the
+  *    amount of time spent updating rsets during a collection.
+  */
+  size_t _green_zone;
+  size_t _yellow_zone;
+  size_t _red_zone;
+  size_t _min_yellow_zone_size;
+
+  G1ConcurrentRefine(size_t green_zone,
+                     size_t yellow_zone,
+                     size_t red_zone,
+                     size_t min_yellow_zone_size);
+
+  // Update green/yellow/red zone values based on how well goals are being met.
+  void update_zones(double update_rs_time,
+                    size_t update_rs_processed_buffers,
+                    double goal_ms);
+
+  // Update thread thresholds to account for updated zone values.
+  void update_thread_thresholds();
+
+ public:
+  ~G1ConcurrentRefine();
+
+  // Returns a G1ConcurrentRefine instance if succeeded to create/initialize G1ConcurrentRefine and G1ConcurrentRefineThreads.
+  // Otherwise, returns NULL with error code.
+  static G1ConcurrentRefine* create(jint* ecode);
+
+  void stop();
+
+  void adjust(double update_rs_time, size_t update_rs_processed_buffers, double goal_ms);
+
+  // Iterate over all concurrent refinement threads
+  void threads_do(ThreadClosure *tc);
+
+  // Iterate over all worker refinement threads
+  void worker_threads_do(ThreadClosure * tc);
+
+  // The RS sampling thread has nothing to do with refinement, but is here for now.
+  G1YoungRemSetSamplingThread * sampling_thread() const { return _sample_thread; }
+
+  static uint thread_num();
+
+  void print_worker_threads_on(outputStream* st) const;
+
+  size_t green_zone() const      { return _green_zone;  }
+  size_t yellow_zone() const     { return _yellow_zone; }
+  size_t red_zone() const        { return _red_zone;    }
+};
+
+#endif // SHARE_VM_GC_G1_G1CONCURRENTREFINE_HPP