1 /*
   2  * Copyright (c) 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
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  24 
  25 #ifndef SHARE_GC_G1_G1SHAREDDIRTYCARDQUEUE_HPP
  26 #define SHARE_GC_G1_G1SHAREDDIRTYCARDQUEUE_HPP
  27 
  28 #include "utilities/globalDefinitions.hpp"
  29 #include "utilities/macros.hpp"
  30 
  31 class G1DirtyCardQueueSet;
  32 
  33 // A dirty card queue providing thread-safe enqueue.  A shared global
  34 // instance can be used for cases where a thread-local dirty card can't
  35 // be used.
  36 class G1SharedDirtyCardQueue {
  37   G1DirtyCardQueueSet* const _qset;
  38   void** _buffer;
  39   size_t _index;
  40 
  41   NONCOPYABLE(G1SharedDirtyCardQueue);
  42 
  43 public:
  44   G1SharedDirtyCardQueue(G1DirtyCardQueueSet* qset);
  45   ~G1SharedDirtyCardQueue();    // flushes the queue.
  46 
  47   // Thread-safe addition to shared logging buffer.
  48   void enqueue(void* card_ptr);
  49 
  50   // Flush any pending entries to the qset and remove the buffer.
  51   // Not thread-safe.
  52   void flush();
  53 
  54   // Discard any pending entries.
  55   // Not thread-safe.
  56   void reset();
  57 };
  58 
  59 #endif // SHARE_GC_G1_G1SHAREDDIRTYCARDQUEUE_HPP