1 /*
   2  * Copyright (c) 2001, 2015, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  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).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
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  24 
  25 #ifndef SHARE_VM_GC_G1_G1OOPCLOSURES_HPP
  26 #define SHARE_VM_GC_G1_G1OOPCLOSURES_HPP
  27 
  28 #include "memory/iterator.hpp"
  29 #include "oops/markOop.hpp"
  30 
  31 class HeapRegion;
  32 class G1CollectedHeap;
  33 class G1RemSet;
  34 class ConcurrentMark;
  35 class DirtyCardToOopClosure;
  36 class CMBitMap;
  37 class CMMarkStack;
  38 class G1ParScanThreadState;
  39 class CMTask;
  40 class ReferenceProcessor;
  41 
  42 // A class that scans oops in a given heap region (much as OopsInGenClosure
  43 // scans oops in a generation.)
  44 class OopsInHeapRegionClosure: public ExtendedOopClosure {
  45 protected:
  46   HeapRegion* _from;
  47 public:
  48   void set_region(HeapRegion* from) { _from = from; }
  49 };
  50 
  51 class G1ParClosureSuper : public OopsInHeapRegionClosure {
  52 protected:
  53   G1CollectedHeap* _g1;
  54   G1ParScanThreadState* _par_scan_state;
  55   uint _worker_id;
  56 public:
  57   // Initializes the instance, leaving _par_scan_state uninitialized. Must be done
  58   // later using the set_par_scan_thread_state() method.
  59   G1ParClosureSuper(G1CollectedHeap* g1);
  60   G1ParClosureSuper(G1CollectedHeap* g1, G1ParScanThreadState* par_scan_state);
  61   bool apply_to_weak_ref_discovered_field() { return true; }
  62 
  63   void set_par_scan_thread_state(G1ParScanThreadState* par_scan_state);
  64 };
  65 
  66 class G1ParPushHeapRSClosure : public G1ParClosureSuper {
  67 public:
  68   G1ParPushHeapRSClosure(G1CollectedHeap* g1,
  69                          G1ParScanThreadState* par_scan_state):
  70     G1ParClosureSuper(g1, par_scan_state) { }
  71 
  72   template <class T> void do_oop_nv(T* p);
  73   virtual void do_oop(oop* p)          { do_oop_nv(p); }
  74   virtual void do_oop(narrowOop* p)    { do_oop_nv(p); }
  75 };
  76 
  77 class G1ParScanClosure : public G1ParClosureSuper {
  78 public:
  79   G1ParScanClosure(G1CollectedHeap* g1) : G1ParClosureSuper(g1) { }
  80 
  81   template <class T> void do_oop_nv(T* p);
  82   virtual void do_oop(oop* p)          { do_oop_nv(p); }
  83   virtual void do_oop(narrowOop* p)    { do_oop_nv(p); }
  84 
  85   void set_ref_processor(ReferenceProcessor* ref_processor) { _ref_processor = ref_processor; }
  86 };
  87 
  88 // Add back base class for metadata
  89 class G1ParCopyHelper : public G1ParClosureSuper {
  90 protected:
  91   Klass* _scanned_klass;
  92   ConcurrentMark* _cm;
  93 
  94   // Mark the object if it's not already marked. This is used to mark
  95   // objects pointed to by roots that are guaranteed not to move
  96   // during the GC (i.e., non-CSet objects). It is MT-safe.
  97   void mark_object(oop obj);
  98 
  99   // Mark the object if it's not already marked. This is used to mark
 100   // objects pointed to by roots that have been forwarded during a
 101   // GC. It is MT-safe.
 102   void mark_forwarded_object(oop from_obj, oop to_obj);
 103  public:
 104   G1ParCopyHelper(G1CollectedHeap* g1,  G1ParScanThreadState* par_scan_state);
 105   G1ParCopyHelper(G1CollectedHeap* g1);
 106 
 107   void set_scanned_klass(Klass* k) { _scanned_klass = k; }
 108   template <class T> void do_klass_barrier(T* p, oop new_obj);
 109 };
 110 
 111 enum G1Barrier {
 112   G1BarrierNone,
 113   G1BarrierKlass
 114 };
 115 
 116 enum G1Mark {
 117   G1MarkNone,
 118   G1MarkFromRoot,
 119   G1MarkPromotedFromRoot
 120 };
 121 
 122 template <G1Barrier barrier, G1Mark do_mark_object>
 123 class G1ParCopyClosure : public G1ParCopyHelper {
 124 private:
 125   template <class T> void do_oop_work(T* p);
 126 
 127 public:
 128   G1ParCopyClosure(G1CollectedHeap* g1, G1ParScanThreadState* par_scan_state) :
 129       G1ParCopyHelper(g1, par_scan_state) {
 130     assert(_ref_processor == NULL, "sanity");
 131   }
 132 
 133   G1ParCopyClosure(G1CollectedHeap* g1) : G1ParCopyHelper(g1) {
 134     assert(_ref_processor == NULL, "sanity");
 135   }
 136 
 137   template <class T> void do_oop_nv(T* p) { do_oop_work(p); }
 138   virtual void do_oop(oop* p)       { do_oop_nv(p); }
 139   virtual void do_oop(narrowOop* p) { do_oop_nv(p); }
 140 
 141   G1CollectedHeap*      g1()  { return _g1; };
 142   G1ParScanThreadState* pss() { return _par_scan_state; }
 143 };
 144 
 145 typedef G1ParCopyClosure<G1BarrierNone,  G1MarkNone>             G1ParScanExtRootClosure;
 146 typedef G1ParCopyClosure<G1BarrierNone,  G1MarkFromRoot>         G1ParScanAndMarkExtRootClosure;
 147 typedef G1ParCopyClosure<G1BarrierNone,  G1MarkPromotedFromRoot> G1ParScanAndMarkWeakExtRootClosure;
 148 // We use a separate closure to handle references during evacuation
 149 // failure processing.
 150 
 151 class FilterIntoCSClosure: public ExtendedOopClosure {
 152   G1CollectedHeap* _g1;
 153   OopClosure* _oc;
 154   DirtyCardToOopClosure* _dcto_cl;
 155 public:
 156   FilterIntoCSClosure(  DirtyCardToOopClosure* dcto_cl,
 157                         G1CollectedHeap* g1,
 158                         OopClosure* oc) :
 159     _dcto_cl(dcto_cl), _g1(g1), _oc(oc) { }
 160 
 161   template <class T> void do_oop_nv(T* p);
 162   virtual void do_oop(oop* p)        { do_oop_nv(p); }
 163   virtual void do_oop(narrowOop* p)  { do_oop_nv(p); }
 164   bool apply_to_weak_ref_discovered_field() { return true; }
 165 };
 166 
 167 class FilterOutOfRegionClosure: public ExtendedOopClosure {
 168   HeapWord* _r_bottom;
 169   HeapWord* _r_end;
 170   OopClosure* _oc;
 171 public:
 172   FilterOutOfRegionClosure(HeapRegion* r, OopClosure* oc);
 173   template <class T> void do_oop_nv(T* p);
 174   virtual void do_oop(oop* p) { do_oop_nv(p); }
 175   virtual void do_oop(narrowOop* p) { do_oop_nv(p); }
 176   bool apply_to_weak_ref_discovered_field() { return true; }
 177 };
 178 
 179 // Closure for iterating over object fields during concurrent marking
 180 class G1CMOopClosure : public MetadataAwareOopClosure {
 181 protected:
 182   ConcurrentMark*    _cm;
 183 private:
 184   G1CollectedHeap*   _g1h;
 185   CMTask*            _task;
 186 public:
 187   G1CMOopClosure(G1CollectedHeap* g1h, ConcurrentMark* cm, CMTask* task);
 188   template <class T> void do_oop_nv(T* p);
 189   virtual void do_oop(      oop* p) { do_oop_nv(p); }
 190   virtual void do_oop(narrowOop* p) { do_oop_nv(p); }
 191 };
 192 
 193 // Closure to scan the root regions during concurrent marking
 194 class G1RootRegionScanClosure : public MetadataAwareOopClosure {
 195 private:
 196   G1CollectedHeap* _g1h;
 197   ConcurrentMark*  _cm;
 198   uint _worker_id;
 199 public:
 200   G1RootRegionScanClosure(G1CollectedHeap* g1h, ConcurrentMark* cm,
 201                           uint worker_id) :
 202     _g1h(g1h), _cm(cm), _worker_id(worker_id) { }
 203   template <class T> void do_oop_nv(T* p);
 204   virtual void do_oop(      oop* p) { do_oop_nv(p); }
 205   virtual void do_oop(narrowOop* p) { do_oop_nv(p); }
 206 };
 207 
 208 // Closure that applies the given two closures in sequence.
 209 // Used by the RSet refinement code (when updating RSets
 210 // during an evacuation pause) to record cards containing
 211 // pointers into the collection set.
 212 
 213 class G1Mux2Closure : public ExtendedOopClosure {
 214   OopClosure* _c1;
 215   OopClosure* _c2;
 216 public:
 217   G1Mux2Closure(OopClosure *c1, OopClosure *c2);
 218   template <class T> void do_oop_nv(T* p);
 219   virtual void do_oop(oop* p)        { do_oop_nv(p); }
 220   virtual void do_oop(narrowOop* p)  { do_oop_nv(p); }
 221 };
 222 
 223 // A closure that returns true if it is actually applied
 224 // to a reference
 225 
 226 class G1TriggerClosure : public ExtendedOopClosure {
 227   bool _triggered;
 228 public:
 229   G1TriggerClosure();
 230   bool triggered() const { return _triggered; }
 231   template <class T> void do_oop_nv(T* p);
 232   virtual void do_oop(oop* p)        { do_oop_nv(p); }
 233   virtual void do_oop(narrowOop* p)  { do_oop_nv(p); }
 234 };
 235 
 236 // A closure which uses a triggering closure to determine
 237 // whether to apply an oop closure.
 238 
 239 class G1InvokeIfNotTriggeredClosure: public ExtendedOopClosure {
 240   G1TriggerClosure* _trigger_cl;
 241   OopClosure* _oop_cl;
 242 public:
 243   G1InvokeIfNotTriggeredClosure(G1TriggerClosure* t, OopClosure* oc);
 244   template <class T> void do_oop_nv(T* p);
 245   virtual void do_oop(oop* p)        { do_oop_nv(p); }
 246   virtual void do_oop(narrowOop* p)  { do_oop_nv(p); }
 247 };
 248 
 249 class G1UpdateRSOrPushRefOopClosure: public ExtendedOopClosure {
 250   G1CollectedHeap* _g1;
 251   G1RemSet* _g1_rem_set;
 252   HeapRegion* _from;
 253   G1ParPushHeapRSClosure* _push_ref_cl;
 254   bool _record_refs_into_cset;
 255   uint _worker_i;
 256 
 257 public:
 258   G1UpdateRSOrPushRefOopClosure(G1CollectedHeap* g1h,
 259                                 G1RemSet* rs,
 260                                 G1ParPushHeapRSClosure* push_ref_cl,
 261                                 bool record_refs_into_cset,
 262                                 uint worker_i = 0);
 263 
 264   void set_from(HeapRegion* from) {
 265     assert(from != NULL, "from region must be non-NULL");
 266     _from = from;
 267   }
 268 
 269   bool self_forwarded(oop obj) {
 270     markOop m = obj->mark();
 271     bool result = (m->is_marked() && ((oop)m->decode_pointer() == obj));
 272     return result;
 273   }
 274 
 275   bool apply_to_weak_ref_discovered_field() { return true; }
 276 
 277   template <class T> void do_oop_nv(T* p);
 278   virtual void do_oop(narrowOop* p) { do_oop_nv(p); }
 279   virtual void do_oop(oop* p)       { do_oop_nv(p); }
 280 };
 281 
 282 #endif // SHARE_VM_GC_G1_G1OOPCLOSURES_HPP