sampleList.hpp

/*
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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
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 * 2 along with this work; if not, write to the Free Software Foundation,
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#ifndef SHARE_JFR_LEAKPROFILER_SAMPLING_SAMPLELIST_HPP
#define SHARE_JFR_LEAKPROFILER_SAMPLING_SAMPLELIST_HPP
#include "jfr/utilities/jfrAllocation.hpp"
#include "jfr/utilities/jfrDoublyLinkedList.hpp"

class ObjectSample;

class SampleList : public JfrCHeapObj {
  typedef JfrDoublyLinkedList<ObjectSample> List;
 private:
  List _free_list;
  List _in_use_list;
  const ObjectSample* _last_resolved;
  mutable size_t _allocated;
  const size_t _limit;
  const size_t _cache_size;

  void populate_cache();
  ObjectSample* newSample() const;
  void link(ObjectSample* sample);
  void unlink(ObjectSample* sample);
  void deallocate_samples(List& list);
  void reset(ObjectSample* sample);

 public:
  SampleList(size_t limit, size_t cache_size = 0);
  ~SampleList();

  ObjectSample* get();
  ObjectSample* first() const;
  ObjectSample* last() const;
  const ObjectSample* last_resolved() const;
  void set_last_resolved(const ObjectSample* sample);
  void release(ObjectSample* sample);
  ObjectSample* reuse(ObjectSample* sample);
  bool is_full() const;
  size_t count() const;
};

#endif // SHARE_JFR_LEAKPROFILER_SAMPLING_SAMPLELIST_HPP