hotspot/src/share/vm/gc_implementation/g1/g1OopClosures.hpp
author johnc
Thu, 09 May 2013 11:16:39 -0700
changeset 17327 4bd0581aa231
parent 13728 882756847a04
child 20282 7f9cbdf89af2
permissions -rw-r--r--
7176479: G1: JVM crashes on T5-8 system with 1.5 TB heap Summary: Refactor G1's hot card cache and card counts table into their own files. Simplify the card counts table, including removing the encoding of the card index in each entry. The card counts table now has a 1:1 correspondence with the cards spanned by heap. Space for the card counts table is reserved from virtual memory (rather than C heap) during JVM startup and is committed/expanded when the heap is expanded. Changes were also reviewed-by Vitaly Davidovich. Reviewed-by: tschatzl, jmasa

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#ifndef SHARE_VM_GC_IMPLEMENTATION_G1_G1OOPCLOSURES_HPP
#define SHARE_VM_GC_IMPLEMENTATION_G1_G1OOPCLOSURES_HPP

class HeapRegion;
class G1CollectedHeap;
class G1RemSet;
class ConcurrentMark;
class DirtyCardToOopClosure;
class CMBitMap;
class CMMarkStack;
class G1ParScanThreadState;
class CMTask;
class ReferenceProcessor;

// A class that scans oops in a given heap region (much as OopsInGenClosure
// scans oops in a generation.)
class OopsInHeapRegionClosure: public OopsInGenClosure {
protected:
  HeapRegion* _from;
public:
  void set_region(HeapRegion* from) { _from = from; }
};

class G1ParClosureSuper : public OopsInHeapRegionClosure {
protected:
  G1CollectedHeap* _g1;
  G1RemSet* _g1_rem;
  ConcurrentMark* _cm;
  G1ParScanThreadState* _par_scan_state;
  uint _worker_id;
  bool _during_initial_mark;
  bool _mark_in_progress;
public:
  G1ParClosureSuper(G1CollectedHeap* g1, G1ParScanThreadState* par_scan_state);
  bool apply_to_weak_ref_discovered_field() { return true; }
};

class G1ParPushHeapRSClosure : public G1ParClosureSuper {
public:
  G1ParPushHeapRSClosure(G1CollectedHeap* g1,
                         G1ParScanThreadState* par_scan_state):
    G1ParClosureSuper(g1, par_scan_state) { }

  template <class T> void do_oop_nv(T* p);
  virtual void do_oop(oop* p)          { do_oop_nv(p); }
  virtual void do_oop(narrowOop* p)    { do_oop_nv(p); }
};

class G1ParScanClosure : public G1ParClosureSuper {
public:
  G1ParScanClosure(G1CollectedHeap* g1, G1ParScanThreadState* par_scan_state, ReferenceProcessor* rp) :
    G1ParClosureSuper(g1, par_scan_state)
  {
    assert(_ref_processor == NULL, "sanity");
    _ref_processor = rp;
  }

  template <class T> void do_oop_nv(T* p);
  virtual void do_oop(oop* p)          { do_oop_nv(p); }
  virtual void do_oop(narrowOop* p)    { do_oop_nv(p); }
};

#define G1_PARTIAL_ARRAY_MASK 0x2

template <class T> inline bool has_partial_array_mask(T* ref) {
  return ((uintptr_t)ref & G1_PARTIAL_ARRAY_MASK) == G1_PARTIAL_ARRAY_MASK;
}

template <class T> inline T* set_partial_array_mask(T obj) {
  assert(((uintptr_t)obj & G1_PARTIAL_ARRAY_MASK) == 0, "Information loss!");
  return (T*) ((uintptr_t)obj | G1_PARTIAL_ARRAY_MASK);
}

template <class T> inline oop clear_partial_array_mask(T* ref) {
  return oop((intptr_t)ref & ~G1_PARTIAL_ARRAY_MASK);
}

class G1ParScanPartialArrayClosure : public G1ParClosureSuper {
  G1ParScanClosure _scanner;

public:
  G1ParScanPartialArrayClosure(G1CollectedHeap* g1, G1ParScanThreadState* par_scan_state, ReferenceProcessor* rp) :
    G1ParClosureSuper(g1, par_scan_state), _scanner(g1, par_scan_state, rp)
  {
    assert(_ref_processor == NULL, "sanity");
  }

  G1ParScanClosure* scanner() {
    return &_scanner;
  }

  template <class T> void do_oop_nv(T* p);
  virtual void do_oop(oop* p)       { do_oop_nv(p); }
  virtual void do_oop(narrowOop* p) { do_oop_nv(p); }
};

// Add back base class for metadata
class G1ParCopyHelper : public G1ParClosureSuper {
  Klass* _scanned_klass;

 public:
  G1ParCopyHelper(G1CollectedHeap* g1,  G1ParScanThreadState* par_scan_state) :
      _scanned_klass(NULL),
      G1ParClosureSuper(g1, par_scan_state) {}

  void set_scanned_klass(Klass* k) { _scanned_klass = k; }
  template <class T> void do_klass_barrier(T* p, oop new_obj);
};

template <bool do_gen_barrier, G1Barrier barrier, bool do_mark_object>
class G1ParCopyClosure : public G1ParCopyHelper {
  G1ParScanClosure _scanner;
  template <class T> void do_oop_work(T* p);

protected:
  // Mark the object if it's not already marked. This is used to mark
  // objects pointed to by roots that are guaranteed not to move
  // during the GC (i.e., non-CSet objects). It is MT-safe.
  void mark_object(oop obj);

  // Mark the object if it's not already marked. This is used to mark
  // objects pointed to by roots that have been forwarded during a
  // GC. It is MT-safe.
  void mark_forwarded_object(oop from_obj, oop to_obj);

  oop copy_to_survivor_space(oop obj);

public:
  G1ParCopyClosure(G1CollectedHeap* g1, G1ParScanThreadState* par_scan_state,
                   ReferenceProcessor* rp) :
      _scanner(g1, par_scan_state, rp),
      G1ParCopyHelper(g1, par_scan_state) {
    assert(_ref_processor == NULL, "sanity");
  }

  G1ParScanClosure* scanner() { return &_scanner; }

  template <class T> void do_oop_nv(T* p) {
    do_oop_work(p);
  }
  virtual void do_oop(oop* p)       { do_oop_nv(p); }
  virtual void do_oop(narrowOop* p) { do_oop_nv(p); }
};

typedef G1ParCopyClosure<false, G1BarrierNone, false> G1ParScanExtRootClosure;
typedef G1ParCopyClosure<false, G1BarrierKlass, false> G1ParScanMetadataClosure;


typedef G1ParCopyClosure<false, G1BarrierNone, true> G1ParScanAndMarkExtRootClosure;
typedef G1ParCopyClosure<true,  G1BarrierNone, true> G1ParScanAndMarkClosure;
typedef G1ParCopyClosure<false, G1BarrierKlass, true> G1ParScanAndMarkMetadataClosure;

// The following closure types are no longer used but are retained
// for historical reasons:
// typedef G1ParCopyClosure<false, G1BarrierRS,   false> G1ParScanHeapRSClosure;
// typedef G1ParCopyClosure<false, G1BarrierRS,   true> G1ParScanAndMarkHeapRSClosure;

// The following closure type is defined in g1_specialized_oop_closures.hpp:
//
// typedef G1ParCopyClosure<false, G1BarrierEvac, false> G1ParScanHeapEvacClosure;

// We use a separate closure to handle references during evacuation
// failure processing.
// We could have used another instance of G1ParScanHeapEvacClosure
// (since that closure no longer assumes that the references it
// handles point into the collection set).

typedef G1ParCopyClosure<false, G1BarrierEvac, false> G1ParScanHeapEvacFailureClosure;

class FilterIntoCSClosure: public ExtendedOopClosure {
  G1CollectedHeap* _g1;
  OopClosure* _oc;
  DirtyCardToOopClosure* _dcto_cl;
public:
  FilterIntoCSClosure(  DirtyCardToOopClosure* dcto_cl,
                        G1CollectedHeap* g1,
                        OopClosure* oc) :
    _dcto_cl(dcto_cl), _g1(g1), _oc(oc) { }

  template <class T> void do_oop_nv(T* p);
  virtual void do_oop(oop* p)        { do_oop_nv(p); }
  virtual void do_oop(narrowOop* p)  { do_oop_nv(p); }
  bool apply_to_weak_ref_discovered_field() { return true; }
};

class FilterOutOfRegionClosure: public ExtendedOopClosure {
  HeapWord* _r_bottom;
  HeapWord* _r_end;
  OopClosure* _oc;
public:
  FilterOutOfRegionClosure(HeapRegion* r, OopClosure* oc);
  template <class T> void do_oop_nv(T* p);
  virtual void do_oop(oop* p) { do_oop_nv(p); }
  virtual void do_oop(narrowOop* p) { do_oop_nv(p); }
  bool apply_to_weak_ref_discovered_field() { return true; }
};

// Closure for iterating over object fields during concurrent marking
class G1CMOopClosure : public ExtendedOopClosure {
private:
  G1CollectedHeap*   _g1h;
  ConcurrentMark*    _cm;
  CMTask*            _task;
public:
  G1CMOopClosure(G1CollectedHeap* g1h, ConcurrentMark* cm, CMTask* task);
  template <class T> void do_oop_nv(T* p);
  virtual void do_oop(      oop* p) { do_oop_nv(p); }
  virtual void do_oop(narrowOop* p) { do_oop_nv(p); }
};

// Closure to scan the root regions during concurrent marking
class G1RootRegionScanClosure : public ExtendedOopClosure {
private:
  G1CollectedHeap* _g1h;
  ConcurrentMark*  _cm;
  uint _worker_id;
public:
  G1RootRegionScanClosure(G1CollectedHeap* g1h, ConcurrentMark* cm,
                          uint worker_id) :
    _g1h(g1h), _cm(cm), _worker_id(worker_id) { }
  template <class T> void do_oop_nv(T* p);
  virtual void do_oop(      oop* p) { do_oop_nv(p); }
  virtual void do_oop(narrowOop* p) { do_oop_nv(p); }
};

// Closure that applies the given two closures in sequence.
// Used by the RSet refinement code (when updating RSets
// during an evacuation pause) to record cards containing
// pointers into the collection set.

class G1Mux2Closure : public ExtendedOopClosure {
  OopClosure* _c1;
  OopClosure* _c2;
public:
  G1Mux2Closure(OopClosure *c1, OopClosure *c2);
  template <class T> void do_oop_nv(T* p);
  virtual void do_oop(oop* p)        { do_oop_nv(p); }
  virtual void do_oop(narrowOop* p)  { do_oop_nv(p); }
};

// A closure that returns true if it is actually applied
// to a reference

class G1TriggerClosure : public ExtendedOopClosure {
  bool _triggered;
public:
  G1TriggerClosure();
  bool triggered() const { return _triggered; }
  template <class T> void do_oop_nv(T* p);
  virtual void do_oop(oop* p)        { do_oop_nv(p); }
  virtual void do_oop(narrowOop* p)  { do_oop_nv(p); }
};

// A closure which uses a triggering closure to determine
// whether to apply an oop closure.

class G1InvokeIfNotTriggeredClosure: public ExtendedOopClosure {
  G1TriggerClosure* _trigger_cl;
  OopClosure* _oop_cl;
public:
  G1InvokeIfNotTriggeredClosure(G1TriggerClosure* t, OopClosure* oc);
  template <class T> void do_oop_nv(T* p);
  virtual void do_oop(oop* p)        { do_oop_nv(p); }
  virtual void do_oop(narrowOop* p)  { do_oop_nv(p); }
};

class G1UpdateRSOrPushRefOopClosure: public ExtendedOopClosure {
  G1CollectedHeap* _g1;
  G1RemSet* _g1_rem_set;
  HeapRegion* _from;
  OopsInHeapRegionClosure* _push_ref_cl;
  bool _record_refs_into_cset;
  int _worker_i;

public:
  G1UpdateRSOrPushRefOopClosure(G1CollectedHeap* g1h,
                                G1RemSet* rs,
                                OopsInHeapRegionClosure* push_ref_cl,
                                bool record_refs_into_cset,
                                int worker_i = 0);

  void set_from(HeapRegion* from) {
    assert(from != NULL, "from region must be non-NULL");
    _from = from;
  }

  bool self_forwarded(oop obj) {
    bool result = (obj->is_forwarded() && (obj->forwardee()== obj));
    return result;
  }

  bool apply_to_weak_ref_discovered_field() { return true; }

  template <class T> void do_oop_nv(T* p);
  virtual void do_oop(narrowOop* p) { do_oop_nv(p); }
  virtual void do_oop(oop* p)       { do_oop_nv(p); }
};

#endif // SHARE_VM_GC_IMPLEMENTATION_G1_G1OOPCLOSURES_HPP