1 /*
   2  * Copyright (c) 2016, 2018, 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_JFR_WRITERS_JFRMEMORYWRITERHOST_HPP
  26 #define SHARE_VM_JFR_WRITERS_JFRMEMORYWRITERHOST_HPP
  27 
  28 #include "jfr/writers/jfrStorageHost.inline.hpp"
  29 
  30 #ifdef ASSERT
  31 class ExclusiveAccessAssert {
  32  private:
  33   bool _acquired;
  34  public:
  35   ExclusiveAccessAssert() : _acquired(false) {}
  36   void acquire() { assert_non_acquired(); _acquired = true; }
  37   void release() { assert_acquired(); _acquired = false; }
  38   bool is_acquired() const { return _acquired; }
  39   void assert_acquired() const { assert(_acquired, "Not acquired!"); }
  40   void assert_non_acquired() const { assert(!_acquired, "Already acquired!"); }
  41 };
  42 #else
  43  class ExclusiveAccessAssert {};
  44 #endif
  45 
  46 template <typename Adapter, typename AP, typename AccessAssert = ExclusiveAccessAssert>
  47 class MemoryWriterHost : public StorageHost<Adapter, AP> {
  48   debug_only(AccessAssert _access;)
  49  public:
  50   typedef typename Adapter::StorageType StorageType;
  51  protected:
  52   void bytes(void* dest, const void* buf, size_t len);
  53   MemoryWriterHost(StorageType* storage, Thread* thread);
  54   MemoryWriterHost(StorageType* storage, size_t size);
  55   MemoryWriterHost(Thread* thread);
  56   debug_only(bool is_acquired() const;)
  57  public:
  58   void acquire();
  59   void release();
  60 };
  61 
  62 template <typename Adapter, typename AP>
  63 class AcquireReleaseMemoryWriterHost : public MemoryWriterHost<Adapter, AP> {
  64  public:
  65   typedef typename Adapter::StorageType StorageType;
  66   AcquireReleaseMemoryWriterHost(StorageType* storage, Thread* thread);
  67   AcquireReleaseMemoryWriterHost(StorageType* storage, size_t size);
  68   AcquireReleaseMemoryWriterHost(Thread* thread);
  69   ~AcquireReleaseMemoryWriterHost();
  70 };
  71 
  72 #endif // SHARE_VM_JFR_WRITERS_JFRMEMORYWRITERHOST_HPP