1 /*
   2  * Copyright (c) 2014, 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_VM_JFR_LEAKPROFILER_CHAINS_EDGEQUEUE_HPP
  26 #define SHARE_VM_JFR_LEAKPROFILER_CHAINS_EDGEQUEUE_HPP
  27 
  28 #include "memory/allocation.hpp"
  29 #include "jfr/leakprofiler/chains/edge.hpp"
  30 
  31 class JfrVirtualMemory;
  32 
  33 class EdgeQueue : public CHeapObj<mtTracing> {
  34  private:
  35   JfrVirtualMemory* _vmm;
  36   const size_t _reservation_size_bytes;
  37   const size_t _commit_block_size_bytes;
  38   mutable size_t _top_index;
  39   mutable size_t _bottom_index;
  40  public:
  41   EdgeQueue(size_t reservation_size_bytes, size_t commit_block_size_bytes);
  42   ~EdgeQueue();
  43 
  44   bool initialize();
  45 
  46   void add(const Edge* parent, const oop* ref);
  47   const Edge* remove() const;
  48   const Edge* element_at(size_t index) const;
  49 
  50   size_t top() const;
  51   size_t bottom() const;
  52   bool is_empty() const;
  53   bool is_full() const;
  54 
  55   size_t reserved_size() const;
  56   size_t live_set() const;
  57   size_t sizeof_edge() const; // with alignments
  58 };
  59 
  60 #endif // SHARE_VM_JFR_LEAKPROFILER_CHAINS_EDGEQUEUE_HPP