1 /*
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   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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   6  * under the terms of the GNU General Public License version 2 only, as
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  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
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  24 
  25 #ifndef SHARE_GC_G1_G1OOPCLOSURES_HPP
  26 #define SHARE_GC_G1_G1OOPCLOSURES_HPP
  27 
  28 #include "gc/g1/g1HeapRegionAttr.hpp"
  29 #include "memory/iterator.hpp"
  30 #include "oops/markOop.hpp"
  31 
  32 class HeapRegion;
  33 class G1CollectedHeap;
  34 class G1RemSet;
  35 class G1ConcurrentMark;
  36 class DirtyCardToOopClosure;
  37 class G1CMBitMap;
  38 class G1ParScanThreadState;
  39 class G1ScanEvacuatedObjClosure;
  40 class G1CMTask;
  41 class ReferenceProcessor;
  42 
  43 class G1ScanClosureBase : public BasicOopIterateClosure {
  44 protected:
  45   G1CollectedHeap* _g1h;
  46   G1ParScanThreadState* _par_scan_state;
  47 
  48   G1ScanClosureBase(G1CollectedHeap* g1h, G1ParScanThreadState* par_scan_state);
  49   ~G1ScanClosureBase() { }
  50 
  51   template <class T>
  52   inline void prefetch_and_push(T* p, oop const obj);
  53 
  54   template <class T>
  55   inline void handle_non_cset_obj_common(G1HeapRegionAttr const region_attr, T* p, oop const obj);
  56 public:
  57   virtual ReferenceIterationMode reference_iteration_mode() { return DO_FIELDS; }
  58 
  59   inline void trim_queue_partially();
  60 };
  61 
  62 // Used to scan cards from the DCQS or the remembered sets during garbage collection.
  63 class G1ScanCardClosure : public G1ScanClosureBase {
  64 public:
  65   G1ScanCardClosure(G1CollectedHeap* g1h,
  66                     G1ParScanThreadState* pss) :
  67     G1ScanClosureBase(g1h, pss) { }
  68 
  69   template <class T> void do_oop_work(T* p);
  70   virtual void do_oop(narrowOop* p) { do_oop_work(p); }
  71   virtual void do_oop(oop* p)       { do_oop_work(p); }
  72 };
  73 
  74 // Used during Optional RS scanning to make sure we trim the queues in a timely manner.
  75 class G1ScanRSForOptionalClosure : public OopClosure {
  76   G1CollectedHeap* _g1h;
  77   G1ScanCardClosure* _scan_cl;
  78 public:
  79   G1ScanRSForOptionalClosure(G1CollectedHeap* g1h, G1ScanCardClosure* cl) : _g1h(g1h), _scan_cl(cl) { }
  80 
  81   template <class T> void do_oop_work(T* p);
  82   virtual void do_oop(oop* p)          { do_oop_work(p); }
  83   virtual void do_oop(narrowOop* p)    { do_oop_work(p); }
  84 };
  85 
  86 // This closure is applied to the fields of the objects that have just been copied during evacuation.
  87 class G1ScanEvacuatedObjClosure : public G1ScanClosureBase {
  88   friend class G1ScanInYoungSetter;
  89 
  90   enum ScanningInYoungValues {
  91     False = 0,
  92     True,
  93     Uninitialized
  94   };
  95 
  96   ScanningInYoungValues _scanning_in_young;
  97 
  98 public:
  99   G1ScanEvacuatedObjClosure(G1CollectedHeap* g1h, G1ParScanThreadState* par_scan_state) :
 100     G1ScanClosureBase(g1h, par_scan_state), _scanning_in_young(Uninitialized) { }
 101 
 102   template <class T> void do_oop_work(T* p);
 103   virtual void do_oop(oop* p)          { do_oop_work(p); }
 104   virtual void do_oop(narrowOop* p)    { do_oop_work(p); }
 105 
 106   // We need to do reference discovery while processing evacuated objects.
 107   virtual ReferenceIterationMode reference_iteration_mode() { return DO_DISCOVERED_AND_DISCOVERY; }
 108 
 109   void set_ref_discoverer(ReferenceDiscoverer* rd) {
 110     set_ref_discoverer_internal(rd);
 111   }
 112 };
 113 
 114 // RAII object to properly set the _scanning_in_young field in G1ScanEvacuatedObjClosure.
 115 class G1ScanInYoungSetter : public StackObj {
 116   G1ScanEvacuatedObjClosure* _closure;
 117 
 118 public:
 119   G1ScanInYoungSetter(G1ScanEvacuatedObjClosure* closure, bool new_value) : _closure(closure) {
 120     assert(_closure->_scanning_in_young == G1ScanEvacuatedObjClosure::Uninitialized, "Must not be set");
 121     _closure->_scanning_in_young = new_value ? G1ScanEvacuatedObjClosure::True : G1ScanEvacuatedObjClosure::False;
 122   }
 123 
 124   ~G1ScanInYoungSetter() {
 125     DEBUG_ONLY(_closure->_scanning_in_young = G1ScanEvacuatedObjClosure::Uninitialized;)
 126   }
 127 };
 128 
 129 // Add back base class for metadata
 130 class G1ParCopyHelper : public OopClosure {
 131 protected:
 132   G1CollectedHeap* _g1h;
 133   G1ParScanThreadState* _par_scan_state;
 134   uint _worker_id;              // Cache value from par_scan_state.
 135   ClassLoaderData* _scanned_cld;
 136   G1ConcurrentMark* _cm;
 137 
 138   // Mark the object if it's not already marked. This is used to mark
 139   // objects pointed to by roots that are guaranteed not to move
 140   // during the GC (i.e., non-CSet objects). It is MT-safe.
 141   inline void mark_object(oop obj);
 142 
 143   G1ParCopyHelper(G1CollectedHeap* g1h,  G1ParScanThreadState* par_scan_state);
 144   ~G1ParCopyHelper() { }
 145 
 146  public:
 147   void set_scanned_cld(ClassLoaderData* cld) { _scanned_cld = cld; }
 148   inline void do_cld_barrier(oop new_obj);
 149 
 150   inline void trim_queue_partially();
 151 };
 152 
 153 enum G1Barrier {
 154   G1BarrierNone,
 155   G1BarrierCLD
 156 };
 157 
 158 enum G1Mark {
 159   G1MarkNone,
 160   G1MarkFromRoot,
 161   G1MarkPromotedFromRoot
 162 };
 163 
 164 template <G1Barrier barrier, G1Mark do_mark_object>
 165 class G1ParCopyClosure : public G1ParCopyHelper {
 166 public:
 167   G1ParCopyClosure(G1CollectedHeap* g1h, G1ParScanThreadState* par_scan_state) :
 168       G1ParCopyHelper(g1h, par_scan_state) { }
 169 
 170   template <class T> void do_oop_work(T* p);
 171   virtual void do_oop(oop* p)       { do_oop_work(p); }
 172   virtual void do_oop(narrowOop* p) { do_oop_work(p); }
 173 };
 174 
 175 class G1CLDScanClosure : public CLDClosure {
 176   G1ParCopyHelper* _closure;
 177   bool             _process_only_dirty;
 178   int              _claim;
 179   int              _count;
 180 public:
 181   G1CLDScanClosure(G1ParCopyHelper* closure,
 182                    bool process_only_dirty, int claim_value)
 183   : _closure(closure), _process_only_dirty(process_only_dirty), _claim(claim_value), _count(0) {}
 184   void do_cld(ClassLoaderData* cld);
 185 };
 186 
 187 // Closure for iterating over object fields during concurrent marking
 188 class G1CMOopClosure : public MetadataVisitingOopIterateClosure {
 189   G1CollectedHeap*   _g1h;
 190   G1CMTask*          _task;
 191 public:
 192   G1CMOopClosure(G1CollectedHeap* g1h,G1CMTask* task);
 193   template <class T> void do_oop_work(T* p);
 194   virtual void do_oop(      oop* p) { do_oop_work(p); }
 195   virtual void do_oop(narrowOop* p) { do_oop_work(p); }
 196 };
 197 
 198 // Closure to scan the root regions during concurrent marking
 199 class G1RootRegionScanClosure : public MetadataVisitingOopIterateClosure {
 200 private:
 201   G1CollectedHeap* _g1h;
 202   G1ConcurrentMark* _cm;
 203   uint _worker_id;
 204 public:
 205   G1RootRegionScanClosure(G1CollectedHeap* g1h, G1ConcurrentMark* cm, uint worker_id) :
 206     _g1h(g1h), _cm(cm), _worker_id(worker_id) { }
 207   template <class T> void do_oop_work(T* p);
 208   virtual void do_oop(      oop* p) { do_oop_work(p); }
 209   virtual void do_oop(narrowOop* p) { do_oop_work(p); }
 210 };
 211 
 212 class G1ConcurrentRefineOopClosure: public BasicOopIterateClosure {
 213   G1CollectedHeap* _g1h;
 214   uint _worker_i;
 215 
 216 public:
 217   G1ConcurrentRefineOopClosure(G1CollectedHeap* g1h, uint worker_i) :
 218     _g1h(g1h),
 219     _worker_i(worker_i) {
 220   }
 221 
 222   virtual ReferenceIterationMode reference_iteration_mode() { return DO_FIELDS; }
 223 
 224   template <class T> void do_oop_work(T* p);
 225   virtual void do_oop(narrowOop* p) { do_oop_work(p); }
 226   virtual void do_oop(oop* p)       { do_oop_work(p); }
 227 };
 228 
 229 class G1RebuildRemSetClosure : public BasicOopIterateClosure {
 230   G1CollectedHeap* _g1h;
 231   uint _worker_id;
 232 public:
 233   G1RebuildRemSetClosure(G1CollectedHeap* g1h, uint worker_id) : _g1h(g1h), _worker_id(worker_id) {
 234   }
 235 
 236   template <class T> void do_oop_work(T* p);
 237   virtual void do_oop(oop* p)       { do_oop_work(p); }
 238   virtual void do_oop(narrowOop* p) { do_oop_work(p); }
 239 
 240   virtual ReferenceIterationMode reference_iteration_mode() { return DO_FIELDS; }
 241 };
 242 
 243 #endif // SHARE_GC_G1_G1OOPCLOSURES_HPP