shenandoahConcurrentGC.hpp

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

#include "gc/shared/gcCause.hpp"
#include "gc/shenandoah/shenandoahConcurrentMark.hpp"
#include "gc/shenandoah/shenandoahGC.hpp"
#include "gc/shenandoah/shenandoahHeap.hpp"

class VM_ShenandoahInitMark;
class VM_ShenandoahFinalMarkStartEvac;
class VM_ShenandoahInitUpdateRefs;
class VM_ShenandoahFinalUpdateRefs;

class ShenandoahConcurrentGC : public ShenandoahGC {
  friend class VM_ShenandoahInitMark;
  friend class VM_ShenandoahFinalMarkStartEvac;
  friend class VM_ShenandoahInitUpdateRefs;
  friend class VM_ShenandoahFinalUpdateRefs;
  friend class VM_ShenandoahFinalRoots;

private:
  ShenandoahConcurrentMark  _mark;
  ShenandoahDegenPoint      _degen_point;

public:
  ShenandoahConcurrentGC();
  bool collect(GCCause::Cause cause);
  ShenandoahDegenPoint degen_point() const;

  // Cancel ongoing concurrent GC
  static void cancel();
private:
  // Entry points to STW GC operations, these cause a related safepoint, that then
  // call the entry method below
  void vmop_entry_init_mark();
  void vmop_entry_final_mark();
  void vmop_entry_init_updaterefs();
  void vmop_entry_final_updaterefs();
  void vmop_entry_final_roots();

  // Entry methods to normally STW GC operations. These set up logging, monitoring
  // and workers for net VM operation
  void entry_init_mark();
  void entry_final_mark();
  void entry_init_updaterefs();
  void entry_final_updaterefs();
  void entry_final_roots();

  // Entry methods to normally concurrent GC operations. These set up logging, monitoring
  // for concurrent operation.
  void entry_reset();
  void entry_mark_roots();
  void entry_mark();
  void entry_thread_roots();
  void entry_weak_refs();
  void entry_weak_roots();
  void entry_class_unloading();
  void entry_strong_roots();
  void entry_cleanup_early();
  void entry_evacuate();
  void entry_update_thread_roots();
  void entry_updaterefs();
  void entry_cleanup_complete();

  // Actual work for the phases
  void op_reset();
  void op_init_mark();
  void op_mark_roots();
  void op_mark();
  void op_final_mark();
  void op_thread_roots();
  void op_weak_refs();
  void op_weak_roots();
  void op_class_unloading();
  void op_strong_roots();
  void op_cleanup_early();
  void op_evacuate();
  void op_init_updaterefs();
  void op_updaterefs();
  void op_update_thread_roots();
  void op_final_updaterefs();
  void op_final_roots();
  void op_cleanup_complete();

  // Messages for GC trace events, they have to be immortal for
  // passing around the logging/tracing systems
  const char* init_mark_event_message() const;
  const char* final_mark_event_message() const;
  const char* conc_mark_event_message() const;

  // Check GC cancellation and abort concurrent GC
  bool check_cancellation_and_abort(ShenandoahDegenPoint point);
};

#endif // SHARE_GC_SHENANDOAH_SHENANDOAHCONCURRENTGC_HPP