src/hotspot/share/gc/g1/g1FullCollector.hpp

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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * This code is free software; you can redistribute it and/or modify it
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 *
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 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
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 *
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 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
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#ifndef SHARE_GC_G1_G1FULLCOLLECTOR_HPP
#define SHARE_GC_G1_G1FULLCOLLECTOR_HPP

#include "gc/g1/g1FullGCCompactionPoint.hpp"
#include "gc/g1/g1FullGCHeapRegionAttr.hpp"
#include "gc/g1/g1FullGCMarker.hpp"
#include "gc/g1/g1FullGCOopClosures.hpp"
#include "gc/g1/g1FullGCScope.hpp"
#include "gc/g1/g1RegionMarkStatsCache.hpp"
#include "gc/shared/gcId.hpp"
#include "gc/shared/gcTraceTime.hpp"
#include "gc/shared/preservedMarks.hpp"
#include "gc/shared/referenceProcessor.hpp"
#include "gc/shared/taskqueue.hpp"
#include "memory/allocation.hpp"
#include "oops/oopsHierarchy.hpp"

class WorkerTask;
class G1CMBitMap;
class G1FullGCMarker;
class G1FullGCScope;
class G1FullGCCompactionPoint;
class GCMemoryManager;
class G1HeapRegion;
class ReferenceProcessor;

// Subject-to-discovery closure for reference processing during Full GC. During
// Full GC the whole heap is subject to discovery.
class G1FullGCSubjectToDiscoveryClosure: public BoolObjectClosure {
public:
  bool do_object_b(oop p) {
    assert(p != nullptr, "must be");
    return true;
  }
};

// Full GC Mark that holds GC id and CPU time trace. Needs to be separate
// from the G1FullCollector and G1FullGCScope to allow the Full GC logging
// to have the same structure as the Young GC logging.
class G1FullGCMark : StackObj {
  GCIdMark       _gc_id;
  G1FullGCTracer _tracer;
  GCTraceCPUTime _cpu_time;
public:
  G1FullGCMark() : _gc_id(), _tracer(), _cpu_time(&_tracer) { }
  G1FullGCTracer* tracer() { return &_tracer; }
};

// The G1FullCollector holds data associated with the current Full GC.
class G1FullCollector : StackObj {
  G1CollectedHeap*          _heap;
  G1FullGCScope             _scope;
  uint                      _num_workers;
  bool                      _has_compaction_targets;
  bool                      _has_humongous;
  G1FullGCMarker**          _markers;
  G1FullGCCompactionPoint** _compaction_points;
  OopQueueSet               _oop_queue_set;
  ObjArrayTaskQueueSet      _array_queue_set;
  PreservedMarksSet         _preserved_marks_set;
  G1FullGCCompactionPoint   _serial_compaction_point;
  G1FullGCCompactionPoint   _humongous_compaction_point;
  G1IsAliveClosure          _is_alive;
  ReferenceProcessorIsAliveMutator _is_alive_mutator;
  G1RegionMarkStats*        _live_stats;
  GrowableArrayCHeap<G1HeapRegion*, mtGC> _humongous_compaction_regions;

  static uint calc_active_workers();

  G1FullGCSubjectToDiscoveryClosure _always_subject_to_discovery;
  ReferenceProcessorSubjectToDiscoveryMutator _is_subject_mutator;

  G1FullGCHeapRegionAttr _region_attr_table;

  HeapWord* volatile* _compaction_tops;

public:
  G1FullCollector(G1CollectedHeap* heap,
                  bool clear_soft_refs,
                  bool do_maximal_compaction,
                  G1FullGCTracer* tracer);
  ~G1FullCollector();

  void prepare_collection();
  void collect();
  void complete_collection(size_t allocation_word_size);

  G1FullGCScope*           scope() { return &_scope; }
  uint                     workers() { return _num_workers; }
  G1FullGCMarker*          marker(uint id) { return _markers[id]; }
  G1FullGCCompactionPoint* compaction_point(uint id) { return _compaction_points[id]; }
  OopQueueSet*             oop_queue_set() { return &_oop_queue_set; }
  ObjArrayTaskQueueSet*    array_queue_set() { return &_array_queue_set; }
  PreservedMarksSet*       preserved_mark_set() { return &_preserved_marks_set; }
  G1FullGCCompactionPoint* serial_compaction_point() { return &_serial_compaction_point; }
  G1FullGCCompactionPoint* humongous_compaction_point() { return &_humongous_compaction_point; }
  G1CMBitMap*              mark_bitmap();
  ReferenceProcessor*      reference_processor();
  size_t live_words(uint region_index) const {
    assert(region_index < _heap->max_num_regions(), "sanity");
    return _live_stats[region_index]._live_words;
  }

  void before_marking_update_attribute_table(G1HeapRegion* hr);

  inline bool is_compacting(oop obj) const;
  inline bool is_skip_compacting(uint region_index) const;

  // Are we (potentially) going to compact into this region?
  inline bool is_compaction_target(uint region_index) const;

  inline void set_free(uint region_idx);
  inline bool is_free(uint region_idx) const;
  inline void update_from_compacting_to_skip_compacting(uint region_idx);
  inline void update_from_skip_compacting_to_compacting(uint region_idx);

  inline void set_compaction_top(G1HeapRegion* r, HeapWord* value);
  inline HeapWord* compaction_top(G1HeapRegion* r) const;

  inline void set_has_compaction_targets();
  inline bool has_compaction_targets() const;

  inline void add_humongous_region(G1HeapRegion* hr);
  inline GrowableArrayCHeap<G1HeapRegion*, mtGC>& humongous_compaction_regions();

  uint truncate_parallel_cps();

  inline void set_has_humongous();
  inline bool has_humongous();

private:
  void phase1_mark_live_objects();
  void phase2_prepare_compaction();

  void phase2a_determine_worklists();
  bool phase2b_forward_oops();
  void phase2c_prepare_serial_compaction();
  void phase2d_prepare_humongous_compaction();

  void phase3_adjust_pointers();
  void phase4_do_compaction();
  void phase5_reset_metadata();

  void restore_marks();
  void verify_after_marking();

  void run_task(WorkerTask* task);
};


#endif // SHARE_GC_G1_G1FULLCOLLECTOR_HPP