342
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1 /*
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2 * Copyright 2001-2007 Sun Microsystems, Inc. All Rights Reserved.
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3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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4 *
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5 * This code is free software; you can redistribute it and/or modify it
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6 * under the terms of the GNU General Public License version 2 only, as
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7 * published by the Free Software Foundation.
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8 *
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9 * This code is distributed in the hope that it will be useful, but WITHOUT
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10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
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11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
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12 * version 2 for more details (a copy is included in the LICENSE file that
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13 * accompanied this code).
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14 *
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15 * You should have received a copy of the GNU General Public License version
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16 * 2 along with this work; if not, write to the Free Software Foundation,
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17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
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18 *
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19 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
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20 * CA 95054 USA or visit www.sun.com if you need additional information or
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21 * have any questions.
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22 *
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23 */
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24
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25 // A "G1CollectedHeap" is an implementation of a java heap for HotSpot.
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26 // It uses the "Garbage First" heap organization and algorithm, which
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27 // may combine concurrent marking with parallel, incremental compaction of
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28 // heap subsets that will yield large amounts of garbage.
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29
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30 class HeapRegion;
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31 class HeapRegionSeq;
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32 class HeapRegionList;
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33 class PermanentGenerationSpec;
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34 class GenerationSpec;
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35 class OopsInHeapRegionClosure;
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36 class G1ScanHeapEvacClosure;
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37 class ObjectClosure;
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38 class SpaceClosure;
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39 class CompactibleSpaceClosure;
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40 class Space;
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41 class G1CollectorPolicy;
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42 class GenRemSet;
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43 class G1RemSet;
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44 class HeapRegionRemSetIterator;
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45 class ConcurrentMark;
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46 class ConcurrentMarkThread;
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47 class ConcurrentG1Refine;
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48 class ConcurrentZFThread;
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49
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50 // If want to accumulate detailed statistics on work queues
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51 // turn this on.
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52 #define G1_DETAILED_STATS 0
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53
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54 #if G1_DETAILED_STATS
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55 # define IF_G1_DETAILED_STATS(code) code
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56 #else
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57 # define IF_G1_DETAILED_STATS(code)
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58 #endif
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59
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60 typedef GenericTaskQueue<oop*> RefToScanQueue;
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61 typedef GenericTaskQueueSet<oop*> RefToScanQueueSet;
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62
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63 enum G1GCThreadGroups {
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64 G1CRGroup = 0,
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65 G1ZFGroup = 1,
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66 G1CMGroup = 2,
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67 G1CLGroup = 3
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68 };
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69
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70 enum GCAllocPurpose {
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71 GCAllocForTenured,
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72 GCAllocForSurvived,
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73 GCAllocPurposeCount
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74 };
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75
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76 class YoungList : public CHeapObj {
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77 private:
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78 G1CollectedHeap* _g1h;
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79
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80 HeapRegion* _head;
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81
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82 HeapRegion* _scan_only_head;
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83 HeapRegion* _scan_only_tail;
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84 size_t _length;
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85 size_t _scan_only_length;
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86
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87 size_t _last_sampled_rs_lengths;
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88 size_t _sampled_rs_lengths;
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89 HeapRegion* _curr;
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90 HeapRegion* _curr_scan_only;
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91
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92 HeapRegion* _survivor_head;
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93 HeapRegion* _survivors_tail;
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94 size_t _survivor_length;
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95
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96 void empty_list(HeapRegion* list);
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97
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98 public:
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99 YoungList(G1CollectedHeap* g1h);
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100
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101 void push_region(HeapRegion* hr);
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102 void add_survivor_region(HeapRegion* hr);
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103 HeapRegion* pop_region();
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104 void empty_list();
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105 bool is_empty() { return _length == 0; }
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106 size_t length() { return _length; }
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107 size_t scan_only_length() { return _scan_only_length; }
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108
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109 void rs_length_sampling_init();
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110 bool rs_length_sampling_more();
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111 void rs_length_sampling_next();
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112
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113 void reset_sampled_info() {
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114 _last_sampled_rs_lengths = 0;
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115 }
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116 size_t sampled_rs_lengths() { return _last_sampled_rs_lengths; }
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117
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118 // for development purposes
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119 void reset_auxilary_lists();
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120 HeapRegion* first_region() { return _head; }
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121 HeapRegion* first_scan_only_region() { return _scan_only_head; }
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122 HeapRegion* first_survivor_region() { return _survivor_head; }
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123 HeapRegion* par_get_next_scan_only_region() {
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124 MutexLockerEx x(ParGCRareEvent_lock, Mutex::_no_safepoint_check_flag);
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125 HeapRegion* ret = _curr_scan_only;
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126 if (ret != NULL)
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127 _curr_scan_only = ret->get_next_young_region();
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128 return ret;
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129 }
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130
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131 // debugging
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132 bool check_list_well_formed();
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133 bool check_list_empty(bool ignore_scan_only_list,
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134 bool check_sample = true);
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135 void print();
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136 };
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137
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138 class RefineCardTableEntryClosure;
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139 class G1CollectedHeap : public SharedHeap {
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140 friend class VM_G1CollectForAllocation;
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141 friend class VM_GenCollectForPermanentAllocation;
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142 friend class VM_G1CollectFull;
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143 friend class VM_G1IncCollectionPause;
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144 friend class VM_G1PopRegionCollectionPause;
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145 friend class VMStructs;
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146
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147 // Closures used in implementation.
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148 friend class G1ParCopyHelper;
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149 friend class G1IsAliveClosure;
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150 friend class G1EvacuateFollowersClosure;
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151 friend class G1ParScanThreadState;
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152 friend class G1ParScanClosureSuper;
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153 friend class G1ParEvacuateFollowersClosure;
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154 friend class G1ParTask;
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155 friend class G1FreeGarbageRegionClosure;
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156 friend class RefineCardTableEntryClosure;
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157 friend class G1PrepareCompactClosure;
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158 friend class RegionSorter;
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159 friend class CountRCClosure;
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160 friend class EvacPopObjClosure;
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161
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162 // Other related classes.
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163 friend class G1MarkSweep;
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164
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165 private:
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166 enum SomePrivateConstants {
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167 VeryLargeInBytes = HeapRegion::GrainBytes/2,
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168 VeryLargeInWords = VeryLargeInBytes/HeapWordSize,
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169 MinHeapDeltaBytes = 10 * HeapRegion::GrainBytes, // FIXME
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170 NumAPIs = HeapRegion::MaxAge
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171 };
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172
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173
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174 // The one and only G1CollectedHeap, so static functions can find it.
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175 static G1CollectedHeap* _g1h;
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176
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177 // Storage for the G1 heap (excludes the permanent generation).
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178 VirtualSpace _g1_storage;
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179 MemRegion _g1_reserved;
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180
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181 // The part of _g1_storage that is currently committed.
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182 MemRegion _g1_committed;
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183
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184 // The maximum part of _g1_storage that has ever been committed.
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185 MemRegion _g1_max_committed;
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186
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187 // The number of regions that are completely free.
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188 size_t _free_regions;
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189
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190 // The number of regions we could create by expansion.
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191 size_t _expansion_regions;
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192
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193 // Return the number of free regions in the heap (by direct counting.)
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194 size_t count_free_regions();
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195 // Return the number of free regions on the free and unclean lists.
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196 size_t count_free_regions_list();
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197
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198 // The block offset table for the G1 heap.
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199 G1BlockOffsetSharedArray* _bot_shared;
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200
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201 // Move all of the regions off the free lists, then rebuild those free
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202 // lists, before and after full GC.
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203 void tear_down_region_lists();
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204 void rebuild_region_lists();
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205 // This sets all non-empty regions to need zero-fill (which they will if
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206 // they are empty after full collection.)
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207 void set_used_regions_to_need_zero_fill();
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208
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209 // The sequence of all heap regions in the heap.
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210 HeapRegionSeq* _hrs;
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211
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212 // The region from which normal-sized objects are currently being
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213 // allocated. May be NULL.
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214 HeapRegion* _cur_alloc_region;
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215
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216 // Postcondition: cur_alloc_region == NULL.
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217 void abandon_cur_alloc_region();
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218
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219 // The to-space memory regions into which objects are being copied during
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220 // a GC.
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221 HeapRegion* _gc_alloc_regions[GCAllocPurposeCount];
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222 uint _gc_alloc_region_counts[GCAllocPurposeCount];
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223
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224 // A list of the regions that have been set to be alloc regions in the
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225 // current collection.
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226 HeapRegion* _gc_alloc_region_list;
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227
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228 // When called by par thread, require par_alloc_during_gc_lock() to be held.
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229 void push_gc_alloc_region(HeapRegion* hr);
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230
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231 // This should only be called single-threaded. Undeclares all GC alloc
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232 // regions.
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233 void forget_alloc_region_list();
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234
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235 // Should be used to set an alloc region, because there's other
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236 // associated bookkeeping.
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237 void set_gc_alloc_region(int purpose, HeapRegion* r);
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238
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239 // Check well-formedness of alloc region list.
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240 bool check_gc_alloc_regions();
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241
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242 // Outside of GC pauses, the number of bytes used in all regions other
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243 // than the current allocation region.
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244 size_t _summary_bytes_used;
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245
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246 // Summary information about popular objects; method to print it.
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247 NumberSeq _pop_obj_rc_at_copy;
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248 void print_popularity_summary_info() const;
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249
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250 unsigned _gc_time_stamp;
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251
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252 size_t* _surviving_young_words;
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253
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254 void setup_surviving_young_words();
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255 void update_surviving_young_words(size_t* surv_young_words);
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256 void cleanup_surviving_young_words();
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257
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258 protected:
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259
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260 // Returns "true" iff none of the gc alloc regions have any allocations
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261 // since the last call to "save_marks".
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262 bool all_alloc_regions_no_allocs_since_save_marks();
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263 // Calls "note_end_of_copying on all gc alloc_regions.
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264 void all_alloc_regions_note_end_of_copying();
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265
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266 // The number of regions allocated to hold humongous objects.
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267 int _num_humongous_regions;
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268 YoungList* _young_list;
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269
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270 // The current policy object for the collector.
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271 G1CollectorPolicy* _g1_policy;
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272
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273 // Parallel allocation lock to protect the current allocation region.
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274 Mutex _par_alloc_during_gc_lock;
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275 Mutex* par_alloc_during_gc_lock() { return &_par_alloc_during_gc_lock; }
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276
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277 // If possible/desirable, allocate a new HeapRegion for normal object
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278 // allocation sufficient for an allocation of the given "word_size".
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279 // If "do_expand" is true, will attempt to expand the heap if necessary
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280 // to to satisfy the request. If "zero_filled" is true, requires a
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281 // zero-filled region.
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282 // (Returning NULL will trigger a GC.)
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283 virtual HeapRegion* newAllocRegion_work(size_t word_size,
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284 bool do_expand,
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285 bool zero_filled);
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286
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287 virtual HeapRegion* newAllocRegion(size_t word_size,
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288 bool zero_filled = true) {
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289 return newAllocRegion_work(word_size, false, zero_filled);
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290 }
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291 virtual HeapRegion* newAllocRegionWithExpansion(int purpose,
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292 size_t word_size,
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293 bool zero_filled = true);
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294
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295 // Attempt to allocate an object of the given (very large) "word_size".
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296 // Returns "NULL" on failure.
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297 virtual HeapWord* humongousObjAllocate(size_t word_size);
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298
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299 // If possible, allocate a block of the given word_size, else return "NULL".
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300 // Returning NULL will trigger GC or heap expansion.
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301 // These two methods have rather awkward pre- and
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302 // post-conditions. If they are called outside a safepoint, then
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303 // they assume that the caller is holding the heap lock. Upon return
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304 // they release the heap lock, if they are returning a non-NULL
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305 // value. attempt_allocation_slow() also dirties the cards of a
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306 // newly-allocated young region after it releases the heap
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307 // lock. This change in interface was the neatest way to achieve
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308 // this card dirtying without affecting mem_allocate(), which is a
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309 // more frequently called method. We tried two or three different
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310 // approaches, but they were even more hacky.
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311 HeapWord* attempt_allocation(size_t word_size,
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312 bool permit_collection_pause = true);
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313
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314 HeapWord* attempt_allocation_slow(size_t word_size,
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315 bool permit_collection_pause = true);
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316
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317 // Allocate blocks during garbage collection. Will ensure an
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318 // allocation region, either by picking one or expanding the
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319 // heap, and then allocate a block of the given size. The block
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320 // may not be a humongous - it must fit into a single heap region.
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321 HeapWord* allocate_during_gc(GCAllocPurpose purpose, size_t word_size);
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322 HeapWord* par_allocate_during_gc(GCAllocPurpose purpose, size_t word_size);
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323
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324 HeapWord* allocate_during_gc_slow(GCAllocPurpose purpose,
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325 HeapRegion* alloc_region,
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326 bool par,
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327 size_t word_size);
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328
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329 // Ensure that no further allocations can happen in "r", bearing in mind
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330 // that parallel threads might be attempting allocations.
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331 void par_allocate_remaining_space(HeapRegion* r);
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332
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333 // Helper function for two callbacks below.
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334 // "full", if true, indicates that the GC is for a System.gc() request,
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335 // and should collect the entire heap. If "clear_all_soft_refs" is true,
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336 // all soft references are cleared during the GC. If "full" is false,
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337 // "word_size" describes the allocation that the GC should
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338 // attempt (at least) to satisfy.
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339 void do_collection(bool full, bool clear_all_soft_refs,
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340 size_t word_size);
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341
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342 // Callback from VM_G1CollectFull operation.
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343 // Perform a full collection.
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344 void do_full_collection(bool clear_all_soft_refs);
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345
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346 // Resize the heap if necessary after a full collection. If this is
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347 // after a collect-for allocation, "word_size" is the allocation size,
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348 // and will be considered part of the used portion of the heap.
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349 void resize_if_necessary_after_full_collection(size_t word_size);
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350
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351 // Callback from VM_G1CollectForAllocation operation.
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352 // This function does everything necessary/possible to satisfy a
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353 // failed allocation request (including collection, expansion, etc.)
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354 HeapWord* satisfy_failed_allocation(size_t word_size);
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355
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356 // Attempting to expand the heap sufficiently
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357 // to support an allocation of the given "word_size". If
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358 // successful, perform the allocation and return the address of the
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359 // allocated block, or else "NULL".
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360 virtual HeapWord* expand_and_allocate(size_t word_size);
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361
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362 public:
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363 // Expand the garbage-first heap by at least the given size (in bytes!).
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364 // (Rounds up to a HeapRegion boundary.)
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365 virtual void expand(size_t expand_bytes);
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366
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367 // Do anything common to GC's.
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368 virtual void gc_prologue(bool full);
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369 virtual void gc_epilogue(bool full);
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370
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371 protected:
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372
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373 // Shrink the garbage-first heap by at most the given size (in bytes!).
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374 // (Rounds down to a HeapRegion boundary.)
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375 virtual void shrink(size_t expand_bytes);
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376 void shrink_helper(size_t expand_bytes);
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377
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378 // Do an incremental collection: identify a collection set, and evacuate
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379 // its live objects elsewhere.
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380 virtual void do_collection_pause();
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381
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382 // The guts of the incremental collection pause, executed by the vm
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383 // thread. If "popular_region" is non-NULL, this pause should evacuate
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384 // this single region whose remembered set has gotten large, moving
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385 // any popular objects to one of the popular regions.
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386 virtual void do_collection_pause_at_safepoint(HeapRegion* popular_region);
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387
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388 // Actually do the work of evacuating the collection set.
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389 virtual void evacuate_collection_set();
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390
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391 // If this is an appropriate right time, do a collection pause.
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392 // The "word_size" argument, if non-zero, indicates the size of an
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393 // allocation request that is prompting this query.
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394 void do_collection_pause_if_appropriate(size_t word_size);
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395
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396 // The g1 remembered set of the heap.
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397 G1RemSet* _g1_rem_set;
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398 // And it's mod ref barrier set, used to track updates for the above.
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399 ModRefBarrierSet* _mr_bs;
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400
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401 // The Heap Region Rem Set Iterator.
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402 HeapRegionRemSetIterator** _rem_set_iterator;
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403
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404 // The closure used to refine a single card.
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405 RefineCardTableEntryClosure* _refine_cte_cl;
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406
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407 // A function to check the consistency of dirty card logs.
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408 void check_ct_logs_at_safepoint();
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409
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410 // After a collection pause, make the regions in the CS into free
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411 // regions.
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412 void free_collection_set(HeapRegion* cs_head);
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413
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414 // Applies "scan_non_heap_roots" to roots outside the heap,
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415 // "scan_rs" to roots inside the heap (having done "set_region" to
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416 // indicate the region in which the root resides), and does "scan_perm"
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417 // (setting the generation to the perm generation.) If "scan_rs" is
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418 // NULL, then this step is skipped. The "worker_i"
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419 // param is for use with parallel roots processing, and should be
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420 // the "i" of the calling parallel worker thread's work(i) function.
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421 // In the sequential case this param will be ignored.
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422 void g1_process_strong_roots(bool collecting_perm_gen,
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423 SharedHeap::ScanningOption so,
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424 OopClosure* scan_non_heap_roots,
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425 OopsInHeapRegionClosure* scan_rs,
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426 OopsInHeapRegionClosure* scan_so,
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427 OopsInGenClosure* scan_perm,
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428 int worker_i);
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429
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430 void scan_scan_only_set(OopsInHeapRegionClosure* oc,
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431 int worker_i);
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432 void scan_scan_only_region(HeapRegion* hr,
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433 OopsInHeapRegionClosure* oc,
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434 int worker_i);
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435
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436 // Apply "blk" to all the weak roots of the system. These include
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437 // JNI weak roots, the code cache, system dictionary, symbol table,
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438 // string table, and referents of reachable weak refs.
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439 void g1_process_weak_roots(OopClosure* root_closure,
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440 OopClosure* non_root_closure);
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441
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442 // Invoke "save_marks" on all heap regions.
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443 void save_marks();
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444
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445 // Free a heap region.
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446 void free_region(HeapRegion* hr);
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447 // A component of "free_region", exposed for 'batching'.
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448 // All the params after "hr" are out params: the used bytes of the freed
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449 // region(s), the number of H regions cleared, the number of regions
|
|
450 // freed, and pointers to the head and tail of a list of freed contig
|
|
451 // regions, linked throught the "next_on_unclean_list" field.
|
|
452 void free_region_work(HeapRegion* hr,
|
|
453 size_t& pre_used,
|
|
454 size_t& cleared_h,
|
|
455 size_t& freed_regions,
|
|
456 UncleanRegionList* list,
|
|
457 bool par = false);
|
|
458
|
|
459
|
|
460 // The concurrent marker (and the thread it runs in.)
|
|
461 ConcurrentMark* _cm;
|
|
462 ConcurrentMarkThread* _cmThread;
|
|
463 bool _mark_in_progress;
|
|
464
|
|
465 // The concurrent refiner.
|
|
466 ConcurrentG1Refine* _cg1r;
|
|
467
|
|
468 // The concurrent zero-fill thread.
|
|
469 ConcurrentZFThread* _czft;
|
|
470
|
|
471 // The parallel task queues
|
|
472 RefToScanQueueSet *_task_queues;
|
|
473
|
|
474 // True iff a evacuation has failed in the current collection.
|
|
475 bool _evacuation_failed;
|
|
476
|
|
477 // Set the attribute indicating whether evacuation has failed in the
|
|
478 // current collection.
|
|
479 void set_evacuation_failed(bool b) { _evacuation_failed = b; }
|
|
480
|
|
481 // Failed evacuations cause some logical from-space objects to have
|
|
482 // forwarding pointers to themselves. Reset them.
|
|
483 void remove_self_forwarding_pointers();
|
|
484
|
|
485 // When one is non-null, so is the other. Together, they each pair is
|
|
486 // an object with a preserved mark, and its mark value.
|
|
487 GrowableArray<oop>* _objs_with_preserved_marks;
|
|
488 GrowableArray<markOop>* _preserved_marks_of_objs;
|
|
489
|
|
490 // Preserve the mark of "obj", if necessary, in preparation for its mark
|
|
491 // word being overwritten with a self-forwarding-pointer.
|
|
492 void preserve_mark_if_necessary(oop obj, markOop m);
|
|
493
|
|
494 // The stack of evac-failure objects left to be scanned.
|
|
495 GrowableArray<oop>* _evac_failure_scan_stack;
|
|
496 // The closure to apply to evac-failure objects.
|
|
497
|
|
498 OopsInHeapRegionClosure* _evac_failure_closure;
|
|
499 // Set the field above.
|
|
500 void
|
|
501 set_evac_failure_closure(OopsInHeapRegionClosure* evac_failure_closure) {
|
|
502 _evac_failure_closure = evac_failure_closure;
|
|
503 }
|
|
504
|
|
505 // Push "obj" on the scan stack.
|
|
506 void push_on_evac_failure_scan_stack(oop obj);
|
|
507 // Process scan stack entries until the stack is empty.
|
|
508 void drain_evac_failure_scan_stack();
|
|
509 // True iff an invocation of "drain_scan_stack" is in progress; to
|
|
510 // prevent unnecessary recursion.
|
|
511 bool _drain_in_progress;
|
|
512
|
|
513 // Do any necessary initialization for evacuation-failure handling.
|
|
514 // "cl" is the closure that will be used to process evac-failure
|
|
515 // objects.
|
|
516 void init_for_evac_failure(OopsInHeapRegionClosure* cl);
|
|
517 // Do any necessary cleanup for evacuation-failure handling data
|
|
518 // structures.
|
|
519 void finalize_for_evac_failure();
|
|
520
|
|
521 // An attempt to evacuate "obj" has failed; take necessary steps.
|
|
522 void handle_evacuation_failure(oop obj);
|
|
523 oop handle_evacuation_failure_par(OopsInHeapRegionClosure* cl, oop obj);
|
|
524 void handle_evacuation_failure_common(oop obj, markOop m);
|
|
525
|
|
526
|
|
527 // Ensure that the relevant gc_alloc regions are set.
|
|
528 void get_gc_alloc_regions();
|
|
529 // We're done with GC alloc regions; release them, as appropriate.
|
|
530 void release_gc_alloc_regions();
|
|
531
|
|
532 // ("Weak") Reference processing support
|
|
533 ReferenceProcessor* _ref_processor;
|
|
534
|
|
535 enum G1H_process_strong_roots_tasks {
|
|
536 G1H_PS_mark_stack_oops_do,
|
|
537 G1H_PS_refProcessor_oops_do,
|
|
538 // Leave this one last.
|
|
539 G1H_PS_NumElements
|
|
540 };
|
|
541
|
|
542 SubTasksDone* _process_strong_tasks;
|
|
543
|
|
544 // Allocate space to hold a popular object. Result is guaranteed below
|
|
545 // "popular_object_boundary()". Note: CURRENTLY halts the system if we
|
|
546 // run out of space to hold popular objects.
|
|
547 HeapWord* allocate_popular_object(size_t word_size);
|
|
548
|
|
549 // The boundary between popular and non-popular objects.
|
|
550 HeapWord* _popular_object_boundary;
|
|
551
|
|
552 HeapRegionList* _popular_regions_to_be_evacuated;
|
|
553
|
|
554 // Compute which objects in "single_region" are popular. If any are,
|
|
555 // evacuate them to a popular region, leaving behind forwarding pointers,
|
|
556 // and select "popular_region" as the single collection set region.
|
|
557 // Otherwise, leave the collection set null.
|
|
558 void popularity_pause_preamble(HeapRegion* populer_region);
|
|
559
|
|
560 // Compute which objects in "single_region" are popular, and evacuate
|
|
561 // them to a popular region, leaving behind forwarding pointers.
|
|
562 // Returns "true" if at least one popular object is discovered and
|
|
563 // evacuated. In any case, "*max_rc" is set to the maximum reference
|
|
564 // count of an object in the region.
|
|
565 bool compute_reference_counts_and_evac_popular(HeapRegion* populer_region,
|
|
566 size_t* max_rc);
|
|
567 // Subroutines used in the above.
|
|
568 bool _rc_region_above;
|
|
569 size_t _rc_region_diff;
|
|
570 jint* obj_rc_addr(oop obj) {
|
|
571 uintptr_t obj_addr = (uintptr_t)obj;
|
|
572 if (_rc_region_above) {
|
|
573 jint* res = (jint*)(obj_addr + _rc_region_diff);
|
|
574 assert((uintptr_t)res > obj_addr, "RC region is above.");
|
|
575 return res;
|
|
576 } else {
|
|
577 jint* res = (jint*)(obj_addr - _rc_region_diff);
|
|
578 assert((uintptr_t)res < obj_addr, "RC region is below.");
|
|
579 return res;
|
|
580 }
|
|
581 }
|
|
582 jint obj_rc(oop obj) {
|
|
583 return *obj_rc_addr(obj);
|
|
584 }
|
|
585 void inc_obj_rc(oop obj) {
|
|
586 (*obj_rc_addr(obj))++;
|
|
587 }
|
|
588 void atomic_inc_obj_rc(oop obj);
|
|
589
|
|
590
|
|
591 // Number of popular objects and bytes (latter is cheaper!).
|
|
592 size_t pop_object_used_objs();
|
|
593 size_t pop_object_used_bytes();
|
|
594
|
|
595 // Index of the popular region in which allocation is currently being
|
|
596 // done.
|
|
597 int _cur_pop_hr_index;
|
|
598
|
|
599 // List of regions which require zero filling.
|
|
600 UncleanRegionList _unclean_region_list;
|
|
601 bool _unclean_regions_coming;
|
|
602
|
|
603 bool check_age_cohort_well_formed_work(int a, HeapRegion* hr);
|
|
604
|
|
605 public:
|
|
606 void set_refine_cte_cl_concurrency(bool concurrent);
|
|
607
|
|
608 RefToScanQueue *task_queue(int i);
|
|
609
|
|
610 // Create a G1CollectedHeap with the specified policy.
|
|
611 // Must call the initialize method afterwards.
|
|
612 // May not return if something goes wrong.
|
|
613 G1CollectedHeap(G1CollectorPolicy* policy);
|
|
614
|
|
615 // Initialize the G1CollectedHeap to have the initial and
|
|
616 // maximum sizes, permanent generation, and remembered and barrier sets
|
|
617 // specified by the policy object.
|
|
618 jint initialize();
|
|
619
|
|
620 void ref_processing_init();
|
|
621
|
|
622 void set_par_threads(int t) {
|
|
623 SharedHeap::set_par_threads(t);
|
|
624 _process_strong_tasks->set_par_threads(t);
|
|
625 }
|
|
626
|
|
627 virtual CollectedHeap::Name kind() const {
|
|
628 return CollectedHeap::G1CollectedHeap;
|
|
629 }
|
|
630
|
|
631 // The current policy object for the collector.
|
|
632 G1CollectorPolicy* g1_policy() const { return _g1_policy; }
|
|
633
|
|
634 // Adaptive size policy. No such thing for g1.
|
|
635 virtual AdaptiveSizePolicy* size_policy() { return NULL; }
|
|
636
|
|
637 // The rem set and barrier set.
|
|
638 G1RemSet* g1_rem_set() const { return _g1_rem_set; }
|
|
639 ModRefBarrierSet* mr_bs() const { return _mr_bs; }
|
|
640
|
|
641 // The rem set iterator.
|
|
642 HeapRegionRemSetIterator* rem_set_iterator(int i) {
|
|
643 return _rem_set_iterator[i];
|
|
644 }
|
|
645
|
|
646 HeapRegionRemSetIterator* rem_set_iterator() {
|
|
647 return _rem_set_iterator[0];
|
|
648 }
|
|
649
|
|
650 unsigned get_gc_time_stamp() {
|
|
651 return _gc_time_stamp;
|
|
652 }
|
|
653
|
|
654 void reset_gc_time_stamp() {
|
|
655 _gc_time_stamp = 0;
|
|
656 }
|
|
657
|
|
658 void iterate_dirty_card_closure(bool concurrent, int worker_i);
|
|
659
|
|
660 // The shared block offset table array.
|
|
661 G1BlockOffsetSharedArray* bot_shared() const { return _bot_shared; }
|
|
662
|
|
663 // Reference Processing accessor
|
|
664 ReferenceProcessor* ref_processor() { return _ref_processor; }
|
|
665
|
|
666 // Reserved (g1 only; super method includes perm), capacity and the used
|
|
667 // portion in bytes.
|
|
668 size_t g1_reserved_obj_bytes() { return _g1_reserved.byte_size(); }
|
|
669 virtual size_t capacity() const;
|
|
670 virtual size_t used() const;
|
|
671 size_t recalculate_used() const;
|
|
672 #ifndef PRODUCT
|
|
673 size_t recalculate_used_regions() const;
|
|
674 #endif // PRODUCT
|
|
675
|
|
676 // These virtual functions do the actual allocation.
|
|
677 virtual HeapWord* mem_allocate(size_t word_size,
|
|
678 bool is_noref,
|
|
679 bool is_tlab,
|
|
680 bool* gc_overhead_limit_was_exceeded);
|
|
681
|
|
682 // Some heaps may offer a contiguous region for shared non-blocking
|
|
683 // allocation, via inlined code (by exporting the address of the top and
|
|
684 // end fields defining the extent of the contiguous allocation region.)
|
|
685 // But G1CollectedHeap doesn't yet support this.
|
|
686
|
|
687 // Return an estimate of the maximum allocation that could be performed
|
|
688 // without triggering any collection or expansion activity. In a
|
|
689 // generational collector, for example, this is probably the largest
|
|
690 // allocation that could be supported (without expansion) in the youngest
|
|
691 // generation. It is "unsafe" because no locks are taken; the result
|
|
692 // should be treated as an approximation, not a guarantee, for use in
|
|
693 // heuristic resizing decisions.
|
|
694 virtual size_t unsafe_max_alloc();
|
|
695
|
|
696 virtual bool is_maximal_no_gc() const {
|
|
697 return _g1_storage.uncommitted_size() == 0;
|
|
698 }
|
|
699
|
|
700 // The total number of regions in the heap.
|
|
701 size_t n_regions();
|
|
702
|
|
703 // The number of regions that are completely free.
|
|
704 size_t max_regions();
|
|
705
|
|
706 // The number of regions that are completely free.
|
|
707 size_t free_regions();
|
|
708
|
|
709 // The number of regions that are not completely free.
|
|
710 size_t used_regions() { return n_regions() - free_regions(); }
|
|
711
|
|
712 // True iff the ZF thread should run.
|
|
713 bool should_zf();
|
|
714
|
|
715 // The number of regions available for "regular" expansion.
|
|
716 size_t expansion_regions() { return _expansion_regions; }
|
|
717
|
|
718 #ifndef PRODUCT
|
|
719 bool regions_accounted_for();
|
|
720 bool print_region_accounting_info();
|
|
721 void print_region_counts();
|
|
722 #endif
|
|
723
|
|
724 HeapRegion* alloc_region_from_unclean_list(bool zero_filled);
|
|
725 HeapRegion* alloc_region_from_unclean_list_locked(bool zero_filled);
|
|
726
|
|
727 void put_region_on_unclean_list(HeapRegion* r);
|
|
728 void put_region_on_unclean_list_locked(HeapRegion* r);
|
|
729
|
|
730 void prepend_region_list_on_unclean_list(UncleanRegionList* list);
|
|
731 void prepend_region_list_on_unclean_list_locked(UncleanRegionList* list);
|
|
732
|
|
733 void set_unclean_regions_coming(bool b);
|
|
734 void set_unclean_regions_coming_locked(bool b);
|
|
735 // Wait for cleanup to be complete.
|
|
736 void wait_for_cleanup_complete();
|
|
737 // Like above, but assumes that the calling thread owns the Heap_lock.
|
|
738 void wait_for_cleanup_complete_locked();
|
|
739
|
|
740 // Return the head of the unclean list.
|
|
741 HeapRegion* peek_unclean_region_list_locked();
|
|
742 // Remove and return the head of the unclean list.
|
|
743 HeapRegion* pop_unclean_region_list_locked();
|
|
744
|
|
745 // List of regions which are zero filled and ready for allocation.
|
|
746 HeapRegion* _free_region_list;
|
|
747 // Number of elements on the free list.
|
|
748 size_t _free_region_list_size;
|
|
749
|
|
750 // If the head of the unclean list is ZeroFilled, move it to the free
|
|
751 // list.
|
|
752 bool move_cleaned_region_to_free_list_locked();
|
|
753 bool move_cleaned_region_to_free_list();
|
|
754
|
|
755 void put_free_region_on_list_locked(HeapRegion* r);
|
|
756 void put_free_region_on_list(HeapRegion* r);
|
|
757
|
|
758 // Remove and return the head element of the free list.
|
|
759 HeapRegion* pop_free_region_list_locked();
|
|
760
|
|
761 // If "zero_filled" is true, we first try the free list, then we try the
|
|
762 // unclean list, zero-filling the result. If "zero_filled" is false, we
|
|
763 // first try the unclean list, then the zero-filled list.
|
|
764 HeapRegion* alloc_free_region_from_lists(bool zero_filled);
|
|
765
|
|
766 // Verify the integrity of the region lists.
|
|
767 void remove_allocated_regions_from_lists();
|
|
768 bool verify_region_lists();
|
|
769 bool verify_region_lists_locked();
|
|
770 size_t unclean_region_list_length();
|
|
771 size_t free_region_list_length();
|
|
772
|
|
773 // Perform a collection of the heap; intended for use in implementing
|
|
774 // "System.gc". This probably implies as full a collection as the
|
|
775 // "CollectedHeap" supports.
|
|
776 virtual void collect(GCCause::Cause cause);
|
|
777
|
|
778 // The same as above but assume that the caller holds the Heap_lock.
|
|
779 void collect_locked(GCCause::Cause cause);
|
|
780
|
|
781 // This interface assumes that it's being called by the
|
|
782 // vm thread. It collects the heap assuming that the
|
|
783 // heap lock is already held and that we are executing in
|
|
784 // the context of the vm thread.
|
|
785 virtual void collect_as_vm_thread(GCCause::Cause cause);
|
|
786
|
|
787 // True iff a evacuation has failed in the most-recent collection.
|
|
788 bool evacuation_failed() { return _evacuation_failed; }
|
|
789
|
|
790 // Free a region if it is totally full of garbage. Returns the number of
|
|
791 // bytes freed (0 ==> didn't free it).
|
|
792 size_t free_region_if_totally_empty(HeapRegion *hr);
|
|
793 void free_region_if_totally_empty_work(HeapRegion *hr,
|
|
794 size_t& pre_used,
|
|
795 size_t& cleared_h_regions,
|
|
796 size_t& freed_regions,
|
|
797 UncleanRegionList* list,
|
|
798 bool par = false);
|
|
799
|
|
800 // If we've done free region work that yields the given changes, update
|
|
801 // the relevant global variables.
|
|
802 void finish_free_region_work(size_t pre_used,
|
|
803 size_t cleared_h_regions,
|
|
804 size_t freed_regions,
|
|
805 UncleanRegionList* list);
|
|
806
|
|
807
|
|
808 // Returns "TRUE" iff "p" points into the allocated area of the heap.
|
|
809 virtual bool is_in(const void* p) const;
|
|
810
|
|
811 // Return "TRUE" iff the given object address is within the collection
|
|
812 // set.
|
|
813 inline bool obj_in_cs(oop obj);
|
|
814
|
|
815 // Return "TRUE" iff the given object address is in the reserved
|
|
816 // region of g1 (excluding the permanent generation).
|
|
817 bool is_in_g1_reserved(const void* p) const {
|
|
818 return _g1_reserved.contains(p);
|
|
819 }
|
|
820
|
|
821 // Returns a MemRegion that corresponds to the space that has been
|
|
822 // committed in the heap
|
|
823 MemRegion g1_committed() {
|
|
824 return _g1_committed;
|
|
825 }
|
|
826
|
|
827 NOT_PRODUCT( bool is_in_closed_subset(const void* p) const; )
|
|
828
|
|
829 // Dirty card table entries covering a list of young regions.
|
|
830 void dirtyCardsForYoungRegions(CardTableModRefBS* ct_bs, HeapRegion* list);
|
|
831
|
|
832 // This resets the card table to all zeros. It is used after
|
|
833 // a collection pause which used the card table to claim cards.
|
|
834 void cleanUpCardTable();
|
|
835
|
|
836 // Iteration functions.
|
|
837
|
|
838 // Iterate over all the ref-containing fields of all objects, calling
|
|
839 // "cl.do_oop" on each.
|
|
840 virtual void oop_iterate(OopClosure* cl);
|
|
841
|
|
842 // Same as above, restricted to a memory region.
|
|
843 virtual void oop_iterate(MemRegion mr, OopClosure* cl);
|
|
844
|
|
845 // Iterate over all objects, calling "cl.do_object" on each.
|
|
846 virtual void object_iterate(ObjectClosure* cl);
|
|
847
|
|
848 // Iterate over all objects allocated since the last collection, calling
|
|
849 // "cl.do_object" on each. The heap must have been initialized properly
|
|
850 // to support this function, or else this call will fail.
|
|
851 virtual void object_iterate_since_last_GC(ObjectClosure* cl);
|
|
852
|
|
853 // Iterate over all spaces in use in the heap, in ascending address order.
|
|
854 virtual void space_iterate(SpaceClosure* cl);
|
|
855
|
|
856 // Iterate over heap regions, in address order, terminating the
|
|
857 // iteration early if the "doHeapRegion" method returns "true".
|
|
858 void heap_region_iterate(HeapRegionClosure* blk);
|
|
859
|
|
860 // Iterate over heap regions starting with r (or the first region if "r"
|
|
861 // is NULL), in address order, terminating early if the "doHeapRegion"
|
|
862 // method returns "true".
|
|
863 void heap_region_iterate_from(HeapRegion* r, HeapRegionClosure* blk);
|
|
864
|
|
865 // As above but starting from the region at index idx.
|
|
866 void heap_region_iterate_from(int idx, HeapRegionClosure* blk);
|
|
867
|
|
868 HeapRegion* region_at(size_t idx);
|
|
869
|
|
870
|
|
871 // Divide the heap region sequence into "chunks" of some size (the number
|
|
872 // of regions divided by the number of parallel threads times some
|
|
873 // overpartition factor, currently 4). Assumes that this will be called
|
|
874 // in parallel by ParallelGCThreads worker threads with discinct worker
|
|
875 // ids in the range [0..max(ParallelGCThreads-1, 1)], that all parallel
|
|
876 // calls will use the same "claim_value", and that that claim value is
|
|
877 // different from the claim_value of any heap region before the start of
|
|
878 // the iteration. Applies "blk->doHeapRegion" to each of the regions, by
|
|
879 // attempting to claim the first region in each chunk, and, if
|
|
880 // successful, applying the closure to each region in the chunk (and
|
|
881 // setting the claim value of the second and subsequent regions of the
|
|
882 // chunk.) For now requires that "doHeapRegion" always returns "false",
|
|
883 // i.e., that a closure never attempt to abort a traversal.
|
|
884 void heap_region_par_iterate_chunked(HeapRegionClosure* blk,
|
|
885 int worker,
|
|
886 jint claim_value);
|
|
887
|
|
888 // Iterate over the regions (if any) in the current collection set.
|
|
889 void collection_set_iterate(HeapRegionClosure* blk);
|
|
890
|
|
891 // As above but starting from region r
|
|
892 void collection_set_iterate_from(HeapRegion* r, HeapRegionClosure *blk);
|
|
893
|
|
894 // Returns the first (lowest address) compactible space in the heap.
|
|
895 virtual CompactibleSpace* first_compactible_space();
|
|
896
|
|
897 // A CollectedHeap will contain some number of spaces. This finds the
|
|
898 // space containing a given address, or else returns NULL.
|
|
899 virtual Space* space_containing(const void* addr) const;
|
|
900
|
|
901 // A G1CollectedHeap will contain some number of heap regions. This
|
|
902 // finds the region containing a given address, or else returns NULL.
|
|
903 HeapRegion* heap_region_containing(const void* addr) const;
|
|
904
|
|
905 // Like the above, but requires "addr" to be in the heap (to avoid a
|
|
906 // null-check), and unlike the above, may return an continuing humongous
|
|
907 // region.
|
|
908 HeapRegion* heap_region_containing_raw(const void* addr) const;
|
|
909
|
|
910 // A CollectedHeap is divided into a dense sequence of "blocks"; that is,
|
|
911 // each address in the (reserved) heap is a member of exactly
|
|
912 // one block. The defining characteristic of a block is that it is
|
|
913 // possible to find its size, and thus to progress forward to the next
|
|
914 // block. (Blocks may be of different sizes.) Thus, blocks may
|
|
915 // represent Java objects, or they might be free blocks in a
|
|
916 // free-list-based heap (or subheap), as long as the two kinds are
|
|
917 // distinguishable and the size of each is determinable.
|
|
918
|
|
919 // Returns the address of the start of the "block" that contains the
|
|
920 // address "addr". We say "blocks" instead of "object" since some heaps
|
|
921 // may not pack objects densely; a chunk may either be an object or a
|
|
922 // non-object.
|
|
923 virtual HeapWord* block_start(const void* addr) const;
|
|
924
|
|
925 // Requires "addr" to be the start of a chunk, and returns its size.
|
|
926 // "addr + size" is required to be the start of a new chunk, or the end
|
|
927 // of the active area of the heap.
|
|
928 virtual size_t block_size(const HeapWord* addr) const;
|
|
929
|
|
930 // Requires "addr" to be the start of a block, and returns "TRUE" iff
|
|
931 // the block is an object.
|
|
932 virtual bool block_is_obj(const HeapWord* addr) const;
|
|
933
|
|
934 // Does this heap support heap inspection? (+PrintClassHistogram)
|
|
935 virtual bool supports_heap_inspection() const { return true; }
|
|
936
|
|
937 // Section on thread-local allocation buffers (TLABs)
|
|
938 // See CollectedHeap for semantics.
|
|
939
|
|
940 virtual bool supports_tlab_allocation() const;
|
|
941 virtual size_t tlab_capacity(Thread* thr) const;
|
|
942 virtual size_t unsafe_max_tlab_alloc(Thread* thr) const;
|
|
943 virtual HeapWord* allocate_new_tlab(size_t size);
|
|
944
|
|
945 // Can a compiler initialize a new object without store barriers?
|
|
946 // This permission only extends from the creation of a new object
|
|
947 // via a TLAB up to the first subsequent safepoint.
|
|
948 virtual bool can_elide_tlab_store_barriers() const {
|
|
949 // Since G1's TLAB's may, on occasion, come from non-young regions
|
|
950 // as well. (Is there a flag controlling that? XXX)
|
|
951 return false;
|
|
952 }
|
|
953
|
|
954 // Can a compiler elide a store barrier when it writes
|
|
955 // a permanent oop into the heap? Applies when the compiler
|
|
956 // is storing x to the heap, where x->is_perm() is true.
|
|
957 virtual bool can_elide_permanent_oop_store_barriers() const {
|
|
958 // At least until perm gen collection is also G1-ified, at
|
|
959 // which point this should return false.
|
|
960 return true;
|
|
961 }
|
|
962
|
|
963 virtual bool allocs_are_zero_filled();
|
|
964
|
|
965 // The boundary between a "large" and "small" array of primitives, in
|
|
966 // words.
|
|
967 virtual size_t large_typearray_limit();
|
|
968
|
|
969 // All popular objects are guaranteed to have addresses below this
|
|
970 // boundary.
|
|
971 HeapWord* popular_object_boundary() {
|
|
972 return _popular_object_boundary;
|
|
973 }
|
|
974
|
|
975 // Declare the region as one that should be evacuated because its
|
|
976 // remembered set is too large.
|
|
977 void schedule_popular_region_evac(HeapRegion* r);
|
|
978 // If there is a popular region to evacuate it, remove it from the list
|
|
979 // and return it.
|
|
980 HeapRegion* popular_region_to_evac();
|
|
981 // Evacuate the given popular region.
|
|
982 void evac_popular_region(HeapRegion* r);
|
|
983
|
|
984 // Returns "true" iff the given word_size is "very large".
|
|
985 static bool isHumongous(size_t word_size) {
|
|
986 return word_size >= VeryLargeInWords;
|
|
987 }
|
|
988
|
|
989 // Update mod union table with the set of dirty cards.
|
|
990 void updateModUnion();
|
|
991
|
|
992 // Set the mod union bits corresponding to the given memRegion. Note
|
|
993 // that this is always a safe operation, since it doesn't clear any
|
|
994 // bits.
|
|
995 void markModUnionRange(MemRegion mr);
|
|
996
|
|
997 // Records the fact that a marking phase is no longer in progress.
|
|
998 void set_marking_complete() {
|
|
999 _mark_in_progress = false;
|
|
1000 }
|
|
1001 void set_marking_started() {
|
|
1002 _mark_in_progress = true;
|
|
1003 }
|
|
1004 bool mark_in_progress() {
|
|
1005 return _mark_in_progress;
|
|
1006 }
|
|
1007
|
|
1008 // Print the maximum heap capacity.
|
|
1009 virtual size_t max_capacity() const;
|
|
1010
|
|
1011 virtual jlong millis_since_last_gc();
|
|
1012
|
|
1013 // Perform any cleanup actions necessary before allowing a verification.
|
|
1014 virtual void prepare_for_verify();
|
|
1015
|
|
1016 // Perform verification.
|
|
1017 virtual void verify(bool allow_dirty, bool silent);
|
|
1018 virtual void print() const;
|
|
1019 virtual void print_on(outputStream* st) const;
|
|
1020
|
|
1021 virtual void print_gc_threads_on(outputStream* st) const;
|
|
1022 virtual void gc_threads_do(ThreadClosure* tc) const;
|
|
1023
|
|
1024 // Override
|
|
1025 void print_tracing_info() const;
|
|
1026
|
|
1027 // If "addr" is a pointer into the (reserved?) heap, returns a positive
|
|
1028 // number indicating the "arena" within the heap in which "addr" falls.
|
|
1029 // Or else returns 0.
|
|
1030 virtual int addr_to_arena_id(void* addr) const;
|
|
1031
|
|
1032 // Convenience function to be used in situations where the heap type can be
|
|
1033 // asserted to be this type.
|
|
1034 static G1CollectedHeap* heap();
|
|
1035
|
|
1036 void empty_young_list();
|
|
1037 bool should_set_young_locked();
|
|
1038
|
|
1039 void set_region_short_lived_locked(HeapRegion* hr);
|
|
1040 // add appropriate methods for any other surv rate groups
|
|
1041
|
|
1042 void young_list_rs_length_sampling_init() {
|
|
1043 _young_list->rs_length_sampling_init();
|
|
1044 }
|
|
1045 bool young_list_rs_length_sampling_more() {
|
|
1046 return _young_list->rs_length_sampling_more();
|
|
1047 }
|
|
1048 void young_list_rs_length_sampling_next() {
|
|
1049 _young_list->rs_length_sampling_next();
|
|
1050 }
|
|
1051 size_t young_list_sampled_rs_lengths() {
|
|
1052 return _young_list->sampled_rs_lengths();
|
|
1053 }
|
|
1054
|
|
1055 size_t young_list_length() { return _young_list->length(); }
|
|
1056 size_t young_list_scan_only_length() {
|
|
1057 return _young_list->scan_only_length(); }
|
|
1058
|
|
1059 HeapRegion* pop_region_from_young_list() {
|
|
1060 return _young_list->pop_region();
|
|
1061 }
|
|
1062
|
|
1063 HeapRegion* young_list_first_region() {
|
|
1064 return _young_list->first_region();
|
|
1065 }
|
|
1066
|
|
1067 // debugging
|
|
1068 bool check_young_list_well_formed() {
|
|
1069 return _young_list->check_list_well_formed();
|
|
1070 }
|
|
1071 bool check_young_list_empty(bool ignore_scan_only_list,
|
|
1072 bool check_sample = true);
|
|
1073
|
|
1074 // *** Stuff related to concurrent marking. It's not clear to me that so
|
|
1075 // many of these need to be public.
|
|
1076
|
|
1077 // The functions below are helper functions that a subclass of
|
|
1078 // "CollectedHeap" can use in the implementation of its virtual
|
|
1079 // functions.
|
|
1080 // This performs a concurrent marking of the live objects in a
|
|
1081 // bitmap off to the side.
|
|
1082 void doConcurrentMark();
|
|
1083
|
|
1084 // This is called from the marksweep collector which then does
|
|
1085 // a concurrent mark and verifies that the results agree with
|
|
1086 // the stop the world marking.
|
|
1087 void checkConcurrentMark();
|
|
1088 void do_sync_mark();
|
|
1089
|
|
1090 bool isMarkedPrev(oop obj) const;
|
|
1091 bool isMarkedNext(oop obj) const;
|
|
1092
|
|
1093 // Determine if an object is dead, given the object and also
|
|
1094 // the region to which the object belongs. An object is dead
|
|
1095 // iff a) it was not allocated since the last mark and b) it
|
|
1096 // is not marked.
|
|
1097
|
|
1098 bool is_obj_dead(const oop obj, const HeapRegion* hr) const {
|
|
1099 return
|
|
1100 !hr->obj_allocated_since_prev_marking(obj) &&
|
|
1101 !isMarkedPrev(obj);
|
|
1102 }
|
|
1103
|
|
1104 // This is used when copying an object to survivor space.
|
|
1105 // If the object is marked live, then we mark the copy live.
|
|
1106 // If the object is allocated since the start of this mark
|
|
1107 // cycle, then we mark the copy live.
|
|
1108 // If the object has been around since the previous mark
|
|
1109 // phase, and hasn't been marked yet during this phase,
|
|
1110 // then we don't mark it, we just wait for the
|
|
1111 // current marking cycle to get to it.
|
|
1112
|
|
1113 // This function returns true when an object has been
|
|
1114 // around since the previous marking and hasn't yet
|
|
1115 // been marked during this marking.
|
|
1116
|
|
1117 bool is_obj_ill(const oop obj, const HeapRegion* hr) const {
|
|
1118 return
|
|
1119 !hr->obj_allocated_since_next_marking(obj) &&
|
|
1120 !isMarkedNext(obj);
|
|
1121 }
|
|
1122
|
|
1123 // Determine if an object is dead, given only the object itself.
|
|
1124 // This will find the region to which the object belongs and
|
|
1125 // then call the region version of the same function.
|
|
1126
|
|
1127 // Added if it is in permanent gen it isn't dead.
|
|
1128 // Added if it is NULL it isn't dead.
|
|
1129
|
|
1130 bool is_obj_dead(oop obj) {
|
|
1131 HeapRegion* hr = heap_region_containing(obj);
|
|
1132 if (hr == NULL) {
|
|
1133 if (Universe::heap()->is_in_permanent(obj))
|
|
1134 return false;
|
|
1135 else if (obj == NULL) return false;
|
|
1136 else return true;
|
|
1137 }
|
|
1138 else return is_obj_dead(obj, hr);
|
|
1139 }
|
|
1140
|
|
1141 bool is_obj_ill(oop obj) {
|
|
1142 HeapRegion* hr = heap_region_containing(obj);
|
|
1143 if (hr == NULL) {
|
|
1144 if (Universe::heap()->is_in_permanent(obj))
|
|
1145 return false;
|
|
1146 else if (obj == NULL) return false;
|
|
1147 else return true;
|
|
1148 }
|
|
1149 else return is_obj_ill(obj, hr);
|
|
1150 }
|
|
1151
|
|
1152 // The following is just to alert the verification code
|
|
1153 // that a full collection has occurred and that the
|
|
1154 // remembered sets are no longer up to date.
|
|
1155 bool _full_collection;
|
|
1156 void set_full_collection() { _full_collection = true;}
|
|
1157 void clear_full_collection() {_full_collection = false;}
|
|
1158 bool full_collection() {return _full_collection;}
|
|
1159
|
|
1160 ConcurrentMark* concurrent_mark() const { return _cm; }
|
|
1161 ConcurrentG1Refine* concurrent_g1_refine() const { return _cg1r; }
|
|
1162
|
|
1163 public:
|
|
1164 void stop_conc_gc_threads();
|
|
1165
|
|
1166 // <NEW PREDICTION>
|
|
1167
|
|
1168 double predict_region_elapsed_time_ms(HeapRegion* hr, bool young);
|
|
1169 void check_if_region_is_too_expensive(double predicted_time_ms);
|
|
1170 size_t pending_card_num();
|
|
1171 size_t max_pending_card_num();
|
|
1172 size_t cards_scanned();
|
|
1173
|
|
1174 // </NEW PREDICTION>
|
|
1175
|
|
1176 protected:
|
|
1177 size_t _max_heap_capacity;
|
|
1178
|
|
1179 // debug_only(static void check_for_valid_allocation_state();)
|
|
1180
|
|
1181 public:
|
|
1182 // Temporary: call to mark things unimplemented for the G1 heap (e.g.,
|
|
1183 // MemoryService). In productization, we can make this assert false
|
|
1184 // to catch such places (as well as searching for calls to this...)
|
|
1185 static void g1_unimplemented();
|
|
1186
|
|
1187 };
|
|
1188
|
|
1189 // Local Variables: ***
|
|
1190 // c-indentation-style: gnu ***
|
|
1191 // End: ***
|