1 /*
   2  * Copyright (c) 2014, 2015, 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 
  25 #ifndef SHARE_VM_GC_SHARED_GCID_HPP
  26 #define SHARE_VM_GC_SHARED_GCID_HPP
  27 
  28 #include "memory/allocation.hpp"
  29 
  30 class GCId : public AllStatic {
  31   friend class GCIdMark;
  32   static uint _next_id;
  33   static const uint UNDEFINED = (uint)-1;
  34   static const uint create();
  35 
  36  public:
  37   // Returns the currently active GC id. Asserts that there is an active GC id.
  38   static const uint current();
  39   // Same as current() but can return undefined() if no GC id is currently active
  40   static const uint current_raw();
  41   static const uint undefined() { return UNDEFINED; }
  42 };
  43 
  44 class GCIdMark {
  45   uint _gc_id;
  46  public:
  47   GCIdMark();
  48   GCIdMark(uint gc_id);
  49   ~GCIdMark();
  50 };
  51 
  52 #endif // SHARE_VM_GC_SHARED_GCID_HPP