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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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#ifndef SHARE_GC_PARALLEL_SPACECOUNTERS_HPP
#define SHARE_GC_PARALLEL_SPACECOUNTERS_HPP

#include "gc/parallel/mutableSpace.hpp"
#include "gc/shared/generationCounters.hpp"
#include "runtime/perfData.hpp"
#include "utilities/macros.hpp"

// A SpaceCounter is a holder class for performance counters
// that track a space;

class SpaceCounters: public CHeapObj<mtGC> {
  friend class VMStructs;

 private:
  PerfVariable*      _capacity;
  PerfVariable*      _used;
  volatile size_t    _last_used_in_bytes;

  // Constant PerfData types don't need to retain a reference.
  // However, it's a good idea to document them here.
  // PerfConstant*     _size;

  MutableSpace*     _object_space;
  char*             _name_space;

  class UsedHelper;

 public:

  SpaceCounters(const char* name, int ordinal, size_t max_size,
                MutableSpace* m, GenerationCounters* gc);

  ~SpaceCounters();

  inline void update_capacity() {
    _capacity->set_value(_object_space->capacity_in_bytes());
  }

  void update_used();

  inline void update_all() {
    update_used();
    update_capacity();
  }

  const char* name_space() const        { return _name_space; }
};

class SpaceCounters::UsedHelper: public PerfLongSampleHelper {
 private:
  SpaceCounters* _counters;

 public:
  UsedHelper(SpaceCounters* counters) : _counters(counters) { }

  jlong take_sample() override;
};

#endif // SHARE_GC_PARALLEL_SPACECOUNTERS_HPP