1 /*
   2  * Copyright (c) 2001, 2018, 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 "gc/g1/g1InCSetState.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(InCSetState const state, 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 during the Update RS phase to refine remaining cards in the DCQ during garbage collection.
  63 class G1ScanObjsDuringUpdateRSClosure : public G1ScanClosureBase {
  64 public:
  65   G1ScanObjsDuringUpdateRSClosure(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 the Scan RS phase to scan cards from the remembered set during garbage collection.
  75 class G1ScanObjsDuringScanRSClosure : public G1ScanClosureBase {
  76 public:
  77   G1ScanObjsDuringScanRSClosure(G1CollectedHeap* g1h,
  78                                 G1ParScanThreadState* par_scan_state):
  79     G1ScanClosureBase(g1h, par_scan_state) { }
  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 
  87 // This closure is applied to the fields of the objects that have just been copied during evacuation.
  88 class G1ScanEvacuatedObjClosure : public G1ScanClosureBase {
  89   friend class G1ScanInYoungSetter;
  90 
  91   enum ScanningInYoungValues {
  92     False = 0,
  93     True,
  94     Uninitialized
  95   };
  96 
  97   ScanningInYoungValues _scanning_in_young;
  98 
  99 public:
 100   G1ScanEvacuatedObjClosure(G1CollectedHeap* g1h, G1ParScanThreadState* par_scan_state) :
 101     G1ScanClosureBase(g1h, par_scan_state), _scanning_in_young(Uninitialized) { }
 102 
 103   template <class T> void do_oop_work(T* p);
 104   virtual void do_oop(oop* p)          { do_oop_work(p); }
 105   virtual void do_oop(narrowOop* p)    { do_oop_work(p); }
 106 
 107   // We need to do reference discovery while processing evacuated objects.
 108   virtual ReferenceIterationMode reference_iteration_mode() { return DO_DISCOVERED_AND_DISCOVERY; }
 109 
 110   void set_ref_discoverer(ReferenceDiscoverer* rd) {
 111     set_ref_discoverer_internal(rd);
 112   }
 113 };
 114 
 115 // RAII object to properly set the _scanning_in_young field in G1ScanEvacuatedObjClosure.
 116 class G1ScanInYoungSetter : public StackObj {
 117   G1ScanEvacuatedObjClosure* _closure;
 118 
 119 public:
 120   G1ScanInYoungSetter(G1ScanEvacuatedObjClosure* closure, bool new_value) : _closure(closure) {
 121     assert(_closure->_scanning_in_young == G1ScanEvacuatedObjClosure::Uninitialized, "Must not be set");
 122     _closure->_scanning_in_young = new_value ? G1ScanEvacuatedObjClosure::True : G1ScanEvacuatedObjClosure::False;
 123   }
 124 
 125   ~G1ScanInYoungSetter() {
 126     DEBUG_ONLY(_closure->_scanning_in_young = G1ScanEvacuatedObjClosure::Uninitialized;)
 127   }
 128 };
 129 
 130 // Add back base class for metadata
 131 class G1ParCopyHelper : public OopClosure {
 132 protected:
 133   G1CollectedHeap* _g1h;
 134   G1ParScanThreadState* _par_scan_state;
 135   uint _worker_id;              // Cache value from par_scan_state.
 136   ClassLoaderData* _scanned_cld;
 137   G1ConcurrentMark* _cm;
 138 
 139   // Mark the object if it's not already marked. This is used to mark
 140   // objects pointed to by roots that are guaranteed not to move
 141   // during the GC (i.e., non-CSet objects). It is MT-safe.
 142   inline void mark_object(oop obj);
 143 
 144   G1ParCopyHelper(G1CollectedHeap* g1h,  G1ParScanThreadState* par_scan_state);
 145   ~G1ParCopyHelper() { }
 146 
 147  public:
 148   void set_scanned_cld(ClassLoaderData* cld) { _scanned_cld = cld; }
 149   inline void do_cld_barrier(oop new_obj);
 150 
 151   inline void trim_queue_partially();
 152 };
 153 
 154 enum G1Barrier {
 155   G1BarrierNone,
 156   G1BarrierCLD
 157 };
 158 
 159 enum G1Mark {
 160   G1MarkNone,
 161   G1MarkFromRoot,
 162   G1MarkPromotedFromRoot
 163 };
 164 
 165 template <G1Barrier barrier, G1Mark do_mark_object>
 166 class G1ParCopyClosure : public G1ParCopyHelper {
 167 public:
 168   G1ParCopyClosure(G1CollectedHeap* g1h, G1ParScanThreadState* par_scan_state) :
 169       G1ParCopyHelper(g1h, par_scan_state) { }
 170 
 171   template <class T> void do_oop_work(T* p);
 172   virtual void do_oop(oop* p)       { do_oop_work(p); }
 173   virtual void do_oop(narrowOop* p) { do_oop_work(p); }
 174 };
 175 
 176 class G1CLDScanClosure : public CLDClosure {
 177   G1ParCopyHelper* _closure;
 178   bool             _process_only_dirty;
 179   int              _claim;
 180   int              _count;
 181 public:
 182   G1CLDScanClosure(G1ParCopyHelper* closure,
 183                    bool process_only_dirty, int claim_value)
 184   : _closure(closure), _process_only_dirty(process_only_dirty), _claim(claim_value), _count(0) {}
 185   void do_cld(ClassLoaderData* cld);
 186 };
 187 
 188 // Closure for iterating over object fields during concurrent marking
 189 class G1CMOopClosure : public MetadataVisitingOopIterateClosure {
 190   G1CollectedHeap*   _g1h;
 191   G1CMTask*          _task;
 192 public:
 193   G1CMOopClosure(G1CollectedHeap* g1h,G1CMTask* task);
 194   template <class T> void do_oop_work(T* p);
 195   virtual void do_oop(      oop* p) { do_oop_work(p); }
 196   virtual void do_oop(narrowOop* p) { do_oop_work(p); }
 197 };
 198 
 199 // Closure to scan the root regions during concurrent marking
 200 class G1RootRegionScanClosure : public MetadataVisitingOopIterateClosure {
 201 private:
 202   G1CollectedHeap* _g1h;
 203   G1ConcurrentMark* _cm;
 204   uint _worker_id;
 205 public:
 206   G1RootRegionScanClosure(G1CollectedHeap* g1h, G1ConcurrentMark* cm, uint worker_id) :
 207     _g1h(g1h), _cm(cm), _worker_id(worker_id) { }
 208   template <class T> void do_oop_work(T* p);
 209   virtual void do_oop(      oop* p) { do_oop_work(p); }
 210   virtual void do_oop(narrowOop* p) { do_oop_work(p); }
 211 };
 212 
 213 class G1ConcurrentRefineOopClosure: public BasicOopIterateClosure {
 214   G1CollectedHeap* _g1h;
 215   uint _worker_i;
 216 
 217 public:
 218   G1ConcurrentRefineOopClosure(G1CollectedHeap* g1h, uint worker_i) :
 219     _g1h(g1h),
 220     _worker_i(worker_i) {
 221   }
 222 
 223   virtual ReferenceIterationMode reference_iteration_mode() { return DO_FIELDS; }
 224 
 225   template <class T> void do_oop_work(T* p);
 226   virtual void do_oop(narrowOop* p) { do_oop_work(p); }
 227   virtual void do_oop(oop* p)       { do_oop_work(p); }
 228 };
 229 
 230 class G1RebuildRemSetClosure : public BasicOopIterateClosure {
 231   G1CollectedHeap* _g1h;
 232   uint _worker_id;
 233 public:
 234   G1RebuildRemSetClosure(G1CollectedHeap* g1h, uint worker_id) : _g1h(g1h), _worker_id(worker_id) {
 235   }
 236 
 237   template <class T> void do_oop_work(T* p);
 238   virtual void do_oop(oop* p)       { do_oop_work(p); }
 239   virtual void do_oop(narrowOop* p) { do_oop_work(p); }
 240 
 241   virtual ReferenceIterationMode reference_iteration_mode() { return DO_FIELDS; }
 242 };
 243 
 244 #endif // SHARE_VM_GC_G1_G1OOPCLOSURES_HPP