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#ifndef SHARE_GC_G1_G1CONCURRENTREFINETHREAD_HPP
#define SHARE_GC_G1_G1CONCURRENTREFINETHREAD_HPP

#include "gc/shared/concurrentGCThread.hpp"
#include "utilities/ticks.hpp"

// Forward Decl.
class G1ConcurrentRefine;

// One or more G1 Concurrent Refinement Threads may be active if concurrent
// refinement is in progress.
class G1ConcurrentRefineThread: public ConcurrentGCThread {
  friend class VMStructs;
  friend class G1CollectedHeap;

  double _vtime_start;  // Initial virtual time.
  double _vtime_accum;  // Accumulated virtual time.

  Tickspan _total_refinement_time;
  size_t _total_refined_cards;

  uint _worker_id;

  // _notifier and _should_notify form a single-reader / multi-writer
  // notification mechanism.  The owning concurrent refinement thread is the
  // single reader. The writers are (other) threads that call activate() on
  // the thread.  The i-th concurrent refinement thread is responsible for
  // activating thread i+1 if the number of buffers in the queue exceeds a
  // threshold for that i+1th thread.  The 0th (primary) thread is activated
  // by threads that add cards to the dirty card queue set when the primary
  // thread's threshold is exceeded.  activate() is also used to wake up the
  // threads during termination, so even the non-primary thread case is
  // multi-writer.
  Semaphore* _notifier;
  volatile bool _should_notify;

  // Called when no refinement work found for this thread.
  // Returns true if should deactivate.
  bool maybe_deactivate(bool more_work);

  G1ConcurrentRefine* _cr;

  void wait_for_completed_buffers();

  virtual void run_service();
  virtual void stop_service();

public:
  G1ConcurrentRefineThread(G1ConcurrentRefine* cg1r, uint worker_id);

  // Activate this thread.
  void activate();

  Tickspan total_refinement_time() const { return _total_refinement_time; }
  size_t total_refined_cards() const { return _total_refined_cards; }

  // Total virtual time so far.
  double vtime_accum() { return _vtime_accum; }
};

#endif // SHARE_GC_G1_G1CONCURRENTREFINETHREAD_HPP