1 /*
   2  * Copyright (c) 2015, 2017, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  */
  23 
  24 #ifndef SHARE_GC_Z_ZLOCK_HPP
  25 #define SHARE_GC_Z_ZLOCK_HPP
  26 
  27 #include "memory/allocation.hpp"
  28 #include <pthread.h>
  29 
  30 class ZLock {
  31 private:
  32   pthread_mutex_t _lock;
  33 
  34 public:
  35   ZLock();
  36   ~ZLock();
  37 
  38   void lock();
  39   bool try_lock();
  40   void unlock();
  41 };
  42 
  43 class ZReentrantLock {
  44 private:
  45   ZLock            _lock;
  46   Thread* volatile _owner;
  47   uint64_t         _count;
  48 
  49 public:
  50   ZReentrantLock();
  51 
  52   void lock();
  53   void unlock();
  54 
  55   bool is_owned() const;
  56 };
  57 
  58 template <typename T>
  59 class ZLocker : public StackObj {
  60 private:
  61   T* const _lock;
  62 
  63 public:
  64   ZLocker(T* lock);
  65   ~ZLocker();
  66 };
  67 
  68 #endif // SHARE_GC_Z_ZLOCK_HPP