src/hotspot/share/gc/z/zLock.hpp

 /*
- * Copyright (c) 2015, 2017, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2015, 2018, 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.

@@ -32,13 +32,13
   pthread_mutex_t _lock;
 
 public:
   ZLock();
 
-  void lock();
-  bool try_lock();
-  void unlock();
+  virtual void lock();
+  virtual bool try_lock();
+  virtual void unlock();
 };
 
 class ZLocker : public StackObj {
 private:
   ZLock* const _lock;

@@ -46,6 +46,20
 public:
   ZLocker(ZLock* lock);
   ~ZLocker();
 };
 
+class ZReentrantLock: public ZLock {
+  Thread* volatile _owner;
+
+public:
+  ZReentrantLock();
+
+  virtual void lock();
+  virtual bool try_lock();
+  virtual void unlock();
+
+  bool is_owned() const;
+  bool reentrant_lock();
+};
+
 #endif // SHARE_GC_Z_ZLOCK_HPP