rev 55949 : imported patch zgc_discontiguous

   1 /*
   2  * Copyright (c) 2015, 2019, 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_ZVIRTUALMEMORY_HPP
  25 #define SHARE_GC_Z_ZVIRTUALMEMORY_HPP
  26 
  27 #include "gc/z/zMemory.hpp"
  28 
  29 class ZVirtualMemory {
  30   friend class VMStructs;
  31 
  32 private:
  33   uintptr_t _start;
  34   uintptr_t _end;
  35 
  36 public:
  37   ZVirtualMemory();
  38   ZVirtualMemory(uintptr_t start, size_t size);
  39 
  40   bool is_null() const;
  41   uintptr_t start() const;
  42   uintptr_t end() const;
  43   size_t size() const;
  44 
  45   ZVirtualMemory split(size_t size);
  46 };
  47 
  48 class ZVirtualMemoryManager {
  49 private:
  50   ZMemoryManager _manager;
  51   bool           _initialized;
  52 
  53   bool reserve_range(uintptr_t start, size_t size);
  54   size_t reserve(uintptr_t start, size_t size);
  55 
  56 public:
  57   ZVirtualMemoryManager();
  58 
  59   bool is_initialized() const;
  60 
  61   ZVirtualMemory alloc(size_t size, bool alloc_from_front = false);
  62   void free(const ZVirtualMemory& vmem);
  63 };
  64 
  65 #endif // SHARE_GC_Z_ZVIRTUALMEMORY_HPP
--- EOF ---