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

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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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#ifndef SHARE_GC_G1_HEAPREGIONREMSET_HPP
#define SHARE_GC_G1_HEAPREGIONREMSET_HPP

#include "gc/g1/g1CardSet.hpp"
#include "gc/g1/g1CardSetMemory.hpp"
#include "gc/g1/g1CodeRootSet.hpp"
#include "gc/g1/g1FromCardCache.hpp"
#include "runtime/atomic.hpp"
#include "runtime/mutexLocker.hpp"
#include "runtime/safepoint.hpp"
#include "utilities/bitMap.hpp"

class G1CardSetMemoryManager;
class outputStream;

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

  // A set of code blobs (nmethods) whose code contains pointers into
  // the region that owns this RSet.
  G1CodeRootSet _code_roots;

  G1CardSetMemoryManager _card_set_mm;

  // The set of cards in the Java heap
  G1CardSet _card_set;

  HeapRegion* _hr;

  // Cached value of heap base address.
  static HeapWord* _heap_base_address;

  void clear_fcc();

public:
  HeapRegionRemSet(HeapRegion* hr, G1CardSetConfiguration* config);

  bool cardset_is_empty() const {
    return _card_set.is_empty();
  }

  bool is_empty() const {
    return (code_roots_list_length() == 0) && cardset_is_empty();
  }

  bool occupancy_less_or_equal_than(size_t occ) const {
    return (code_roots_list_length() == 0) && _card_set.occupancy_less_or_equal_to(occ);
  }

  // Iterate the card based remembered set for merging them into the card table.
  // The passed closure must be a CardOrRangeVisitor; we use a template parameter
  // to pass it in to facilitate inlining as much as possible.
  template <class CardOrRangeVisitor>
  inline void iterate_for_merge(CardOrRangeVisitor& cl);

  size_t occupied() {
    return _card_set.occupied();
  }

  static void initialize(MemRegion reserved);

  // Coarsening statistics since VM start.
  static G1CardSetCoarsenStats coarsen_stats() { return G1CardSet::coarsen_stats(); }

  inline uintptr_t to_card(OopOrNarrowOopStar from) const;

private:
  enum RemSetState {
    Untracked,
    Updating,
    Complete
  };

  RemSetState _state;

  static const char* _state_strings[];
  static const char* _short_state_strings[];
public:

  const char* get_state_str() const { return _state_strings[_state]; }
  const char* get_short_state_str() const { return _short_state_strings[_state]; }

  bool is_tracked() { return _state != Untracked; }
  bool is_updating() { return _state == Updating; }
  bool is_complete() { return _state == Complete; }

  inline void set_state_untracked();
  inline void set_state_updating();
  inline void set_state_complete();

  inline void add_reference(OopOrNarrowOopStar from, uint tid);

  // The region is being reclaimed; clear its remset, and any mention of
  // entries for this region in other remsets.
  void clear(bool only_cardset = false);

  void reset_table_scanner();

  G1MonotonicArenaMemoryStats card_set_memory_stats() const;

  // The actual # of bytes this hr_remset takes up. Also includes the code
  // root set.
  size_t mem_size() {
    return _card_set.mem_size()
           + (sizeof(HeapRegionRemSet) - sizeof(G1CardSet)) // Avoid double-counting G1CardSet.
           + code_roots_mem_size();
  }

  size_t unused_mem_size() {
    return _card_set.unused_mem_size();
  }

  // Returns the memory occupancy of all static data structures associated
  // with remembered sets.
  static size_t static_mem_size() {
    return G1CardSet::static_mem_size();
  }

  static void print_static_mem_size(outputStream* out);

  inline bool contains_reference(OopOrNarrowOopStar from);

  inline void print_info(outputStream* st, OopOrNarrowOopStar from);

  // Routines for managing the list of code roots that point into
  // the heap region that owns this RSet.
  void add_code_root(nmethod* nm);
  void add_code_root_locked(nmethod* nm);
  void remove_code_root(nmethod* nm);
  void bulk_remove_code_roots();

  // Applies blk->do_code_blob() to each of the entries in _code_roots
  void code_roots_do(CodeBlobClosure* blk) const;

  void clean_code_roots(HeapRegion* hr);

  // Returns the number of elements in _code_roots
  size_t code_roots_list_length() const {
    return _code_roots.length();
  }

  // Returns true if the code roots contains the given
  // nmethod.
  bool code_roots_list_contains(nmethod* nm) {
    return _code_roots.contains(nm);
  }

  // Returns the amount of memory, in bytes, currently
  // consumed by the code roots.
  size_t code_roots_mem_size();

  static void invalidate_from_card_cache(uint start_idx, size_t num_regions) {
    G1FromCardCache::invalidate(start_idx, num_regions);
  }

#ifndef PRODUCT
  static void print_from_card_cache() {
    G1FromCardCache::print();
  }

  static void test();
#endif
};

#endif // SHARE_GC_G1_HEAPREGIONREMSET_HPP