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 #ifndef SERIALGC
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26
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27 // A HeapRegion is the smallest piece of a G1CollectedHeap that
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28 // can be collected independently.
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29
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30 // NOTE: Although a HeapRegion is a Space, its
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31 // Space::initDirtyCardClosure method must not be called.
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32 // The problem is that the existence of this method breaks
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33 // the independence of barrier sets from remembered sets.
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34 // The solution is to remove this method from the definition
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35 // of a Space.
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36
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37 class CompactibleSpace;
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38 class ContiguousSpace;
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39 class HeapRegionRemSet;
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40 class HeapRegionRemSetIterator;
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41 class HeapRegion;
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42
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43 // A dirty card to oop closure for heap regions. It
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44 // knows how to get the G1 heap and how to use the bitmap
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45 // in the concurrent marker used by G1 to filter remembered
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46 // sets.
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47
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48 class HeapRegionDCTOC : public ContiguousSpaceDCTOC {
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49 public:
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50 // Specification of possible DirtyCardToOopClosure filtering.
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51 enum FilterKind {
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52 NoFilterKind,
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53 IntoCSFilterKind,
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54 OutOfRegionFilterKind
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55 };
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56
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57 protected:
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58 HeapRegion* _hr;
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59 FilterKind _fk;
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60 G1CollectedHeap* _g1;
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61
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62 void walk_mem_region_with_cl(MemRegion mr,
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63 HeapWord* bottom, HeapWord* top,
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64 OopClosure* cl);
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65
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66 // We don't specialize this for FilteringClosure; filtering is handled by
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67 // the "FilterKind" mechanism. But we provide this to avoid a compiler
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68 // warning.
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69 void walk_mem_region_with_cl(MemRegion mr,
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70 HeapWord* bottom, HeapWord* top,
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71 FilteringClosure* cl) {
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72 HeapRegionDCTOC::walk_mem_region_with_cl(mr, bottom, top,
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73 (OopClosure*)cl);
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74 }
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75
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76 // Get the actual top of the area on which the closure will
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77 // operate, given where the top is assumed to be (the end of the
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78 // memory region passed to do_MemRegion) and where the object
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79 // at the top is assumed to start. For example, an object may
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80 // start at the top but actually extend past the assumed top,
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81 // in which case the top becomes the end of the object.
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82 HeapWord* get_actual_top(HeapWord* top, HeapWord* top_obj) {
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83 return ContiguousSpaceDCTOC::get_actual_top(top, top_obj);
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84 }
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85
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86 // Walk the given memory region from bottom to (actual) top
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87 // looking for objects and applying the oop closure (_cl) to
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88 // them. The base implementation of this treats the area as
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89 // blocks, where a block may or may not be an object. Sub-
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90 // classes should override this to provide more accurate
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91 // or possibly more efficient walking.
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92 void walk_mem_region(MemRegion mr, HeapWord* bottom, HeapWord* top) {
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93 Filtering_DCTOC::walk_mem_region(mr, bottom, top);
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94 }
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95
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96 public:
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97 HeapRegionDCTOC(G1CollectedHeap* g1,
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98 HeapRegion* hr, OopClosure* cl,
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99 CardTableModRefBS::PrecisionStyle precision,
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100 FilterKind fk);
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101 };
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102
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103
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104 // The complicating factor is that BlockOffsetTable diverged
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105 // significantly, and we need functionality that is only in the G1 version.
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106 // So I copied that code, which led to an alternate G1 version of
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107 // OffsetTableContigSpace. If the two versions of BlockOffsetTable could
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108 // be reconciled, then G1OffsetTableContigSpace could go away.
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109
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110 // The idea behind time stamps is the following. Doing a save_marks on
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111 // all regions at every GC pause is time consuming (if I remember
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112 // well, 10ms or so). So, we would like to do that only for regions
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113 // that are GC alloc regions. To achieve this, we use time
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114 // stamps. For every evacuation pause, G1CollectedHeap generates a
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115 // unique time stamp (essentially a counter that gets
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116 // incremented). Every time we want to call save_marks on a region,
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117 // we set the saved_mark_word to top and also copy the current GC
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118 // time stamp to the time stamp field of the space. Reading the
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119 // saved_mark_word involves checking the time stamp of the
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120 // region. If it is the same as the current GC time stamp, then we
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121 // can safely read the saved_mark_word field, as it is valid. If the
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122 // time stamp of the region is not the same as the current GC time
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123 // stamp, then we instead read top, as the saved_mark_word field is
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124 // invalid. Time stamps (on the regions and also on the
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125 // G1CollectedHeap) are reset at every cleanup (we iterate over
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126 // the regions anyway) and at the end of a Full GC. The current scheme
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127 // that uses sequential unsigned ints will fail only if we have 4b
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128 // evacuation pauses between two cleanups, which is _highly_ unlikely.
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129
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130 class G1OffsetTableContigSpace: public ContiguousSpace {
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131 friend class VMStructs;
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132 protected:
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133 G1BlockOffsetArrayContigSpace _offsets;
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134 Mutex _par_alloc_lock;
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135 volatile unsigned _gc_time_stamp;
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136
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137 public:
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138 // Constructor. If "is_zeroed" is true, the MemRegion "mr" may be
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139 // assumed to contain zeros.
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140 G1OffsetTableContigSpace(G1BlockOffsetSharedArray* sharedOffsetArray,
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141 MemRegion mr, bool is_zeroed = false);
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142
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143 void set_bottom(HeapWord* value);
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144 void set_end(HeapWord* value);
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145
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146 virtual HeapWord* saved_mark_word() const;
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147 virtual void set_saved_mark();
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148 void reset_gc_time_stamp() { _gc_time_stamp = 0; }
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149
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150 virtual void initialize(MemRegion mr, bool clear_space);
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151 virtual void clear();
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152
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153 HeapWord* block_start(const void* p);
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154 HeapWord* block_start_const(const void* p) const;
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155
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156 // Add offset table update.
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157 virtual HeapWord* allocate(size_t word_size);
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158 HeapWord* par_allocate(size_t word_size);
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159
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160 // MarkSweep support phase3
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161 virtual HeapWord* initialize_threshold();
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162 virtual HeapWord* cross_threshold(HeapWord* start, HeapWord* end);
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163
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164 virtual void print() const;
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165 };
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166
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167 class HeapRegion: public G1OffsetTableContigSpace {
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168 friend class VMStructs;
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169 private:
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170
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171 // The next filter kind that should be used for a "new_dcto_cl" call with
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172 // the "traditional" signature.
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173 HeapRegionDCTOC::FilterKind _next_fk;
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174
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175 // Requires that the region "mr" be dense with objects, and begin and end
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176 // with an object.
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177 void oops_in_mr_iterate(MemRegion mr, OopClosure* cl);
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178
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179 // The remembered set for this region.
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180 // (Might want to make this "inline" later, to avoid some alloc failure
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181 // issues.)
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182 HeapRegionRemSet* _rem_set;
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183
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184 G1BlockOffsetArrayContigSpace* offsets() { return &_offsets; }
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185
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186 protected:
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187 // If this region is a member of a HeapRegionSeq, the index in that
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188 // sequence, otherwise -1.
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189 int _hrs_index;
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190
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191 bool _humongous; // starts or continues a humongous object
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192 bool _humongous_start; // starts a humongous object
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193 // For a humongous region, region in which it starts.
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194 HeapRegion* _humongous_start_region;
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195 // For the start region of a humongous sequence, it's original end().
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196 HeapWord* _orig_end;
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197
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198 // True iff the region is in current collection_set.
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199 bool _in_collection_set;
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200
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201 // True iff the region is on the unclean list, waiting to be zero filled.
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202 bool _is_on_unclean_list;
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203
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204 // True iff the region is on the free list, ready for allocation.
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205 bool _is_on_free_list;
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206
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207 // Is this or has it been an allocation region in the current collection
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208 // pause.
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209 bool _is_gc_alloc_region;
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210
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211 // True iff an attempt to evacuate an object in the region failed.
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212 bool _evacuation_failed;
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213
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214 // A heap region may be a member one of a number of special subsets, each
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215 // represented as linked lists through the field below. Currently, these
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216 // sets include:
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217 // The collection set.
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218 // The set of allocation regions used in a collection pause.
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219 // Spaces that may contain gray objects.
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220 HeapRegion* _next_in_special_set;
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221
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222 // next region in the young "generation" region set
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223 HeapRegion* _next_young_region;
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224
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225 // For parallel heapRegion traversal.
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226 jint _claimed;
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227
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228 // We use concurrent marking to determine the amount of live data
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229 // in each heap region.
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230 size_t _prev_marked_bytes; // Bytes known to be live via last completed marking.
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231 size_t _next_marked_bytes; // Bytes known to be live via in-progress marking.
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232
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233 // See "sort_index" method. -1 means is not in the array.
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234 int _sort_index;
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235
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236 // Means it has (or at least had) a very large RS, and should not be
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237 // considered for membership in a collection set.
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238 enum PopularityState {
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239 NotPopular,
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240 PopularPending,
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241 Popular
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242 };
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243 PopularityState _popularity;
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244
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245 // <PREDICTION>
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246 double _gc_efficiency;
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247 // </PREDICTION>
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248
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249 enum YoungType {
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250 NotYoung, // a region is not young
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251 ScanOnly, // a region is young and scan-only
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252 Young, // a region is young
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253 Survivor // a region is young and it contains
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254 // survivor
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255 };
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256
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257 YoungType _young_type;
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258 int _young_index_in_cset;
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259 SurvRateGroup* _surv_rate_group;
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260 int _age_index;
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261
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262 // The start of the unmarked area. The unmarked area extends from this
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263 // word until the top and/or end of the region, and is the part
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264 // of the region for which no marking was done, i.e. objects may
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265 // have been allocated in this part since the last mark phase.
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266 // "prev" is the top at the start of the last completed marking.
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267 // "next" is the top at the start of the in-progress marking (if any.)
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268 HeapWord* _prev_top_at_mark_start;
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269 HeapWord* _next_top_at_mark_start;
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270 // If a collection pause is in progress, this is the top at the start
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271 // of that pause.
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272
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273 // We've counted the marked bytes of objects below here.
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274 HeapWord* _top_at_conc_mark_count;
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275
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276 void init_top_at_mark_start() {
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277 assert(_prev_marked_bytes == 0 &&
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278 _next_marked_bytes == 0,
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279 "Must be called after zero_marked_bytes.");
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280 HeapWord* bot = bottom();
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281 _prev_top_at_mark_start = bot;
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282 _next_top_at_mark_start = bot;
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283 _top_at_conc_mark_count = bot;
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284 }
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285
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286 jint _zfs; // A member of ZeroFillState. Protected by ZF_lock.
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287 Thread* _zero_filler; // If _zfs is ZeroFilling, the thread that (last)
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288 // made it so.
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289
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290 void set_young_type(YoungType new_type) {
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291 //assert(_young_type != new_type, "setting the same type" );
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292 // TODO: add more assertions here
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293 _young_type = new_type;
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294 }
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295
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296 public:
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297 // If "is_zeroed" is "true", the region "mr" can be assumed to contain zeros.
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298 HeapRegion(G1BlockOffsetSharedArray* sharedOffsetArray,
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299 MemRegion mr, bool is_zeroed);
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300
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301 enum SomePublicConstants {
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302 // HeapRegions are GrainBytes-aligned
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303 // and have sizes that are multiples of GrainBytes.
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304 LogOfHRGrainBytes = 20,
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305 LogOfHRGrainWords = LogOfHRGrainBytes - LogHeapWordSize,
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306 GrainBytes = 1 << LogOfHRGrainBytes,
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307 GrainWords = 1 <<LogOfHRGrainWords,
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308 MaxAge = 2, NoOfAges = MaxAge+1
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309 };
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310
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311 // Concurrent refinement requires contiguous heap regions (in which TLABs
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312 // might be allocated) to be zero-filled. Each region therefore has a
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313 // zero-fill-state.
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314 enum ZeroFillState {
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315 NotZeroFilled,
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316 ZeroFilling,
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317 ZeroFilled,
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318 Allocated
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319 };
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320
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321 // If this region is a member of a HeapRegionSeq, the index in that
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322 // sequence, otherwise -1.
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323 int hrs_index() const { return _hrs_index; }
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324 void set_hrs_index(int index) { _hrs_index = index; }
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325
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326 // The number of bytes marked live in the region in the last marking phase.
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327 size_t marked_bytes() { return _prev_marked_bytes; }
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328 // The number of bytes counted in the next marking.
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329 size_t next_marked_bytes() { return _next_marked_bytes; }
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330 // The number of bytes live wrt the next marking.
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331 size_t next_live_bytes() {
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332 return (top() - next_top_at_mark_start())
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333 * HeapWordSize
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334 + next_marked_bytes();
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335 }
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336
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337 // A lower bound on the amount of garbage bytes in the region.
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338 size_t garbage_bytes() {
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339 size_t used_at_mark_start_bytes =
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340 (prev_top_at_mark_start() - bottom()) * HeapWordSize;
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341 assert(used_at_mark_start_bytes >= marked_bytes(),
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342 "Can't mark more than we have.");
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343 return used_at_mark_start_bytes - marked_bytes();
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344 }
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345
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346 // An upper bound on the number of live bytes in the region.
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347 size_t max_live_bytes() { return used() - garbage_bytes(); }
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348
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349 void add_to_marked_bytes(size_t incr_bytes) {
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350 _next_marked_bytes = _next_marked_bytes + incr_bytes;
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351 guarantee( _next_marked_bytes <= used(), "invariant" );
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352 }
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353
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354 void zero_marked_bytes() {
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355 _prev_marked_bytes = _next_marked_bytes = 0;
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356 }
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357
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358 bool isHumongous() const { return _humongous; }
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359 bool startsHumongous() const { return _humongous_start; }
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360 bool continuesHumongous() const { return _humongous && ! _humongous_start; }
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361 // For a humongous region, region in which it starts.
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362 HeapRegion* humongous_start_region() const {
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363 return _humongous_start_region;
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364 }
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365
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366 // Causes the current region to represent a humongous object spanning "n"
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367 // regions.
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368 virtual void set_startsHumongous();
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369
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370 // The regions that continue a humongous sequence should be added using
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371 // this method, in increasing address order.
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372 void set_continuesHumongous(HeapRegion* start);
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373
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374 void add_continuingHumongousRegion(HeapRegion* cont);
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375
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376 // If the region has a remembered set, return a pointer to it.
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377 HeapRegionRemSet* rem_set() const {
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378 return _rem_set;
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379 }
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380
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381 // True iff the region is in current collection_set.
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382 bool in_collection_set() const {
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383 return _in_collection_set;
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384 }
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385 void set_in_collection_set(bool b) {
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386 _in_collection_set = b;
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387 }
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388 HeapRegion* next_in_collection_set() {
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389 assert(in_collection_set(), "should only invoke on member of CS.");
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390 assert(_next_in_special_set == NULL ||
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391 _next_in_special_set->in_collection_set(),
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392 "Malformed CS.");
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393 return _next_in_special_set;
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394 }
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395 void set_next_in_collection_set(HeapRegion* r) {
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396 assert(in_collection_set(), "should only invoke on member of CS.");
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397 assert(r == NULL || r->in_collection_set(), "Malformed CS.");
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398 _next_in_special_set = r;
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399 }
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400
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401 // True iff it is or has been an allocation region in the current
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402 // collection pause.
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403 bool is_gc_alloc_region() const {
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404 return _is_gc_alloc_region;
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405 }
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406 void set_is_gc_alloc_region(bool b) {
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407 _is_gc_alloc_region = b;
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408 }
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409 HeapRegion* next_gc_alloc_region() {
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410 assert(is_gc_alloc_region(), "should only invoke on member of CS.");
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411 assert(_next_in_special_set == NULL ||
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412 _next_in_special_set->is_gc_alloc_region(),
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413 "Malformed CS.");
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414 return _next_in_special_set;
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415 }
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416 void set_next_gc_alloc_region(HeapRegion* r) {
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417 assert(is_gc_alloc_region(), "should only invoke on member of CS.");
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418 assert(r == NULL || r->is_gc_alloc_region(), "Malformed CS.");
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419 _next_in_special_set = r;
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420 }
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421
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422 bool is_reserved() {
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423 return popular();
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424 }
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425
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426 bool is_on_free_list() {
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427 return _is_on_free_list;
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428 }
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429
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430 void set_on_free_list(bool b) {
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431 _is_on_free_list = b;
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432 }
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433
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434 HeapRegion* next_from_free_list() {
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435 assert(is_on_free_list(),
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436 "Should only invoke on free space.");
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437 assert(_next_in_special_set == NULL ||
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438 _next_in_special_set->is_on_free_list(),
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439 "Malformed Free List.");
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440 return _next_in_special_set;
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441 }
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442
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443 void set_next_on_free_list(HeapRegion* r) {
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444 assert(r == NULL || r->is_on_free_list(), "Malformed free list.");
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445 _next_in_special_set = r;
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446 }
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447
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448 bool is_on_unclean_list() {
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449 return _is_on_unclean_list;
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450 }
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|
451
|
|
452 void set_on_unclean_list(bool b);
|
|
453
|
|
454 HeapRegion* next_from_unclean_list() {
|
|
455 assert(is_on_unclean_list(),
|
|
456 "Should only invoke on unclean space.");
|
|
457 assert(_next_in_special_set == NULL ||
|
|
458 _next_in_special_set->is_on_unclean_list(),
|
|
459 "Malformed unclean List.");
|
|
460 return _next_in_special_set;
|
|
461 }
|
|
462
|
|
463 void set_next_on_unclean_list(HeapRegion* r);
|
|
464
|
|
465 HeapRegion* get_next_young_region() { return _next_young_region; }
|
|
466 void set_next_young_region(HeapRegion* hr) {
|
|
467 _next_young_region = hr;
|
|
468 }
|
|
469
|
|
470 // Allows logical separation between objects allocated before and after.
|
|
471 void save_marks();
|
|
472
|
|
473 // Reset HR stuff to default values.
|
|
474 void hr_clear(bool par, bool clear_space);
|
|
475
|
|
476 void initialize(MemRegion mr, bool clear_space);
|
|
477
|
|
478 // Ensure that "this" is zero-filled.
|
|
479 void ensure_zero_filled();
|
|
480 // This one requires that the calling thread holds ZF_mon.
|
|
481 void ensure_zero_filled_locked();
|
|
482
|
|
483 // Get the start of the unmarked area in this region.
|
|
484 HeapWord* prev_top_at_mark_start() const { return _prev_top_at_mark_start; }
|
|
485 HeapWord* next_top_at_mark_start() const { return _next_top_at_mark_start; }
|
|
486
|
|
487 // Apply "cl->do_oop" to (the addresses of) all reference fields in objects
|
|
488 // allocated in the current region before the last call to "save_mark".
|
|
489 void oop_before_save_marks_iterate(OopClosure* cl);
|
|
490
|
|
491 // This call determines the "filter kind" argument that will be used for
|
|
492 // the next call to "new_dcto_cl" on this region with the "traditional"
|
|
493 // signature (i.e., the call below.) The default, in the absence of a
|
|
494 // preceding call to this method, is "NoFilterKind", and a call to this
|
|
495 // method is necessary for each such call, or else it reverts to the
|
|
496 // default.
|
|
497 // (This is really ugly, but all other methods I could think of changed a
|
|
498 // lot of main-line code for G1.)
|
|
499 void set_next_filter_kind(HeapRegionDCTOC::FilterKind nfk) {
|
|
500 _next_fk = nfk;
|
|
501 }
|
|
502
|
|
503 DirtyCardToOopClosure*
|
|
504 new_dcto_closure(OopClosure* cl,
|
|
505 CardTableModRefBS::PrecisionStyle precision,
|
|
506 HeapRegionDCTOC::FilterKind fk);
|
|
507
|
|
508 #if WHASSUP
|
|
509 DirtyCardToOopClosure*
|
|
510 new_dcto_closure(OopClosure* cl,
|
|
511 CardTableModRefBS::PrecisionStyle precision,
|
|
512 HeapWord* boundary) {
|
|
513 assert(boundary == NULL, "This arg doesn't make sense here.");
|
|
514 DirtyCardToOopClosure* res = new_dcto_closure(cl, precision, _next_fk);
|
|
515 _next_fk = HeapRegionDCTOC::NoFilterKind;
|
|
516 return res;
|
|
517 }
|
|
518 #endif
|
|
519
|
|
520 //
|
|
521 // Note the start or end of marking. This tells the heap region
|
|
522 // that the collector is about to start or has finished (concurrently)
|
|
523 // marking the heap.
|
|
524 //
|
|
525
|
|
526 // Note the start of a marking phase. Record the
|
|
527 // start of the unmarked area of the region here.
|
|
528 void note_start_of_marking(bool during_initial_mark) {
|
|
529 init_top_at_conc_mark_count();
|
|
530 _next_marked_bytes = 0;
|
|
531 if (during_initial_mark && is_young() && !is_survivor())
|
|
532 _next_top_at_mark_start = bottom();
|
|
533 else
|
|
534 _next_top_at_mark_start = top();
|
|
535 }
|
|
536
|
|
537 // Note the end of a marking phase. Install the start of
|
|
538 // the unmarked area that was captured at start of marking.
|
|
539 void note_end_of_marking() {
|
|
540 _prev_top_at_mark_start = _next_top_at_mark_start;
|
|
541 _prev_marked_bytes = _next_marked_bytes;
|
|
542 _next_marked_bytes = 0;
|
|
543
|
|
544 guarantee(_prev_marked_bytes <=
|
|
545 (size_t) (prev_top_at_mark_start() - bottom()) * HeapWordSize,
|
|
546 "invariant");
|
|
547 }
|
|
548
|
|
549 // After an evacuation, we need to update _next_top_at_mark_start
|
|
550 // to be the current top. Note this is only valid if we have only
|
|
551 // ever evacuated into this region. If we evacuate, allocate, and
|
|
552 // then evacuate we are in deep doodoo.
|
|
553 void note_end_of_copying() {
|
|
554 assert(top() >= _next_top_at_mark_start,
|
|
555 "Increase only");
|
|
556 _next_top_at_mark_start = top();
|
|
557 }
|
|
558
|
|
559 // Returns "false" iff no object in the region was allocated when the
|
|
560 // last mark phase ended.
|
|
561 bool is_marked() { return _prev_top_at_mark_start != bottom(); }
|
|
562
|
|
563 // If "is_marked()" is true, then this is the index of the region in
|
|
564 // an array constructed at the end of marking of the regions in a
|
|
565 // "desirability" order.
|
|
566 int sort_index() {
|
|
567 return _sort_index;
|
|
568 }
|
|
569 void set_sort_index(int i) {
|
|
570 _sort_index = i;
|
|
571 }
|
|
572
|
|
573 void init_top_at_conc_mark_count() {
|
|
574 _top_at_conc_mark_count = bottom();
|
|
575 }
|
|
576
|
|
577 void set_top_at_conc_mark_count(HeapWord *cur) {
|
|
578 assert(bottom() <= cur && cur <= end(), "Sanity.");
|
|
579 _top_at_conc_mark_count = cur;
|
|
580 }
|
|
581
|
|
582 HeapWord* top_at_conc_mark_count() {
|
|
583 return _top_at_conc_mark_count;
|
|
584 }
|
|
585
|
|
586 void reset_during_compaction() {
|
|
587 guarantee( isHumongous() && startsHumongous(),
|
|
588 "should only be called for humongous regions");
|
|
589
|
|
590 zero_marked_bytes();
|
|
591 init_top_at_mark_start();
|
|
592 }
|
|
593
|
|
594 bool popular() { return _popularity == Popular; }
|
|
595 void set_popular(bool b) {
|
|
596 if (b) {
|
|
597 _popularity = Popular;
|
|
598 } else {
|
|
599 _popularity = NotPopular;
|
|
600 }
|
|
601 }
|
|
602 bool popular_pending() { return _popularity == PopularPending; }
|
|
603 void set_popular_pending(bool b) {
|
|
604 if (b) {
|
|
605 _popularity = PopularPending;
|
|
606 } else {
|
|
607 _popularity = NotPopular;
|
|
608 }
|
|
609 }
|
|
610
|
|
611 // <PREDICTION>
|
|
612 void calc_gc_efficiency(void);
|
|
613 double gc_efficiency() { return _gc_efficiency;}
|
|
614 // </PREDICTION>
|
|
615
|
|
616 bool is_young() const { return _young_type != NotYoung; }
|
|
617 bool is_scan_only() const { return _young_type == ScanOnly; }
|
|
618 bool is_survivor() const { return _young_type == Survivor; }
|
|
619
|
|
620 int young_index_in_cset() const { return _young_index_in_cset; }
|
|
621 void set_young_index_in_cset(int index) {
|
|
622 assert( (index == -1) || is_young(), "pre-condition" );
|
|
623 _young_index_in_cset = index;
|
|
624 }
|
|
625
|
|
626 int age_in_surv_rate_group() {
|
|
627 assert( _surv_rate_group != NULL, "pre-condition" );
|
|
628 assert( _age_index > -1, "pre-condition" );
|
|
629 return _surv_rate_group->age_in_group(_age_index);
|
|
630 }
|
|
631
|
|
632 void recalculate_age_in_surv_rate_group() {
|
|
633 assert( _surv_rate_group != NULL, "pre-condition" );
|
|
634 assert( _age_index > -1, "pre-condition" );
|
|
635 _age_index = _surv_rate_group->recalculate_age_index(_age_index);
|
|
636 }
|
|
637
|
|
638 void record_surv_words_in_group(size_t words_survived) {
|
|
639 assert( _surv_rate_group != NULL, "pre-condition" );
|
|
640 assert( _age_index > -1, "pre-condition" );
|
|
641 int age_in_group = age_in_surv_rate_group();
|
|
642 _surv_rate_group->record_surviving_words(age_in_group, words_survived);
|
|
643 }
|
|
644
|
|
645 int age_in_surv_rate_group_cond() {
|
|
646 if (_surv_rate_group != NULL)
|
|
647 return age_in_surv_rate_group();
|
|
648 else
|
|
649 return -1;
|
|
650 }
|
|
651
|
|
652 SurvRateGroup* surv_rate_group() {
|
|
653 return _surv_rate_group;
|
|
654 }
|
|
655
|
|
656 void install_surv_rate_group(SurvRateGroup* surv_rate_group) {
|
|
657 assert( surv_rate_group != NULL, "pre-condition" );
|
|
658 assert( _surv_rate_group == NULL, "pre-condition" );
|
|
659 assert( is_young(), "pre-condition" );
|
|
660
|
|
661 _surv_rate_group = surv_rate_group;
|
|
662 _age_index = surv_rate_group->next_age_index();
|
|
663 }
|
|
664
|
|
665 void uninstall_surv_rate_group() {
|
|
666 if (_surv_rate_group != NULL) {
|
|
667 assert( _age_index > -1, "pre-condition" );
|
|
668 assert( is_young(), "pre-condition" );
|
|
669
|
|
670 _surv_rate_group = NULL;
|
|
671 _age_index = -1;
|
|
672 } else {
|
|
673 assert( _age_index == -1, "pre-condition" );
|
|
674 }
|
|
675 }
|
|
676
|
|
677 void set_young() { set_young_type(Young); }
|
|
678
|
|
679 void set_scan_only() { set_young_type(ScanOnly); }
|
|
680
|
|
681 void set_survivor() { set_young_type(Survivor); }
|
|
682
|
|
683 void set_not_young() { set_young_type(NotYoung); }
|
|
684
|
|
685 // Determine if an object has been allocated since the last
|
|
686 // mark performed by the collector. This returns true iff the object
|
|
687 // is within the unmarked area of the region.
|
|
688 bool obj_allocated_since_prev_marking(oop obj) const {
|
|
689 return (HeapWord *) obj >= prev_top_at_mark_start();
|
|
690 }
|
|
691 bool obj_allocated_since_next_marking(oop obj) const {
|
|
692 return (HeapWord *) obj >= next_top_at_mark_start();
|
|
693 }
|
|
694
|
|
695 // For parallel heapRegion traversal.
|
|
696 bool claimHeapRegion(int claimValue);
|
|
697 jint claim_value() { return _claimed; }
|
|
698 // Use this carefully: only when you're sure no one is claiming...
|
|
699 void set_claim_value(int claimValue) { _claimed = claimValue; }
|
|
700
|
|
701 // Returns the "evacuation_failed" property of the region.
|
|
702 bool evacuation_failed() { return _evacuation_failed; }
|
|
703
|
|
704 // Sets the "evacuation_failed" property of the region.
|
|
705 void set_evacuation_failed(bool b) {
|
|
706 _evacuation_failed = b;
|
|
707
|
|
708 if (b) {
|
|
709 init_top_at_conc_mark_count();
|
|
710 _next_marked_bytes = 0;
|
|
711 }
|
|
712 }
|
|
713
|
|
714 // Requires that "mr" be entirely within the region.
|
|
715 // Apply "cl->do_object" to all objects that intersect with "mr".
|
|
716 // If the iteration encounters an unparseable portion of the region,
|
|
717 // or if "cl->abort()" is true after a closure application,
|
|
718 // terminate the iteration and return the address of the start of the
|
|
719 // subregion that isn't done. (The two can be distinguished by querying
|
|
720 // "cl->abort()".) Return of "NULL" indicates that the iteration
|
|
721 // completed.
|
|
722 HeapWord*
|
|
723 object_iterate_mem_careful(MemRegion mr, ObjectClosure* cl);
|
|
724
|
|
725 HeapWord*
|
|
726 oops_on_card_seq_iterate_careful(MemRegion mr,
|
|
727 FilterOutOfRegionClosure* cl);
|
|
728
|
|
729 // The region "mr" is entirely in "this", and starts and ends at block
|
|
730 // boundaries. The caller declares that all the contained blocks are
|
|
731 // coalesced into one.
|
|
732 void declare_filled_region_to_BOT(MemRegion mr) {
|
|
733 _offsets.single_block(mr.start(), mr.end());
|
|
734 }
|
|
735
|
|
736 // A version of block start that is guaranteed to find *some* block
|
|
737 // boundary at or before "p", but does not object iteration, and may
|
|
738 // therefore be used safely when the heap is unparseable.
|
|
739 HeapWord* block_start_careful(const void* p) const {
|
|
740 return _offsets.block_start_careful(p);
|
|
741 }
|
|
742
|
|
743 // Requires that "addr" is within the region. Returns the start of the
|
|
744 // first ("careful") block that starts at or after "addr", or else the
|
|
745 // "end" of the region if there is no such block.
|
|
746 HeapWord* next_block_start_careful(HeapWord* addr);
|
|
747
|
|
748 // Returns the zero-fill-state of the current region.
|
|
749 ZeroFillState zero_fill_state() { return (ZeroFillState)_zfs; }
|
|
750 bool zero_fill_is_allocated() { return _zfs == Allocated; }
|
|
751 Thread* zero_filler() { return _zero_filler; }
|
|
752
|
|
753 // Indicate that the contents of the region are unknown, and therefore
|
|
754 // might require zero-filling.
|
|
755 void set_zero_fill_needed() {
|
|
756 set_zero_fill_state_work(NotZeroFilled);
|
|
757 }
|
|
758 void set_zero_fill_in_progress(Thread* t) {
|
|
759 set_zero_fill_state_work(ZeroFilling);
|
|
760 _zero_filler = t;
|
|
761 }
|
|
762 void set_zero_fill_complete();
|
|
763 void set_zero_fill_allocated() {
|
|
764 set_zero_fill_state_work(Allocated);
|
|
765 }
|
|
766
|
|
767 void set_zero_fill_state_work(ZeroFillState zfs);
|
|
768
|
|
769 // This is called when a full collection shrinks the heap.
|
|
770 // We want to set the heap region to a value which says
|
|
771 // it is no longer part of the heap. For now, we'll let "NotZF" fill
|
|
772 // that role.
|
|
773 void reset_zero_fill() {
|
|
774 set_zero_fill_state_work(NotZeroFilled);
|
|
775 _zero_filler = NULL;
|
|
776 }
|
|
777
|
|
778 #define HeapRegion_OOP_SINCE_SAVE_MARKS_DECL(OopClosureType, nv_suffix) \
|
|
779 virtual void oop_since_save_marks_iterate##nv_suffix(OopClosureType* cl);
|
|
780 SPECIALIZED_SINCE_SAVE_MARKS_CLOSURES(HeapRegion_OOP_SINCE_SAVE_MARKS_DECL)
|
|
781
|
|
782 CompactibleSpace* next_compaction_space() const;
|
|
783
|
|
784 virtual void reset_after_compaction();
|
|
785
|
|
786 void print() const;
|
|
787 void print_on(outputStream* st) const;
|
|
788
|
|
789 // Override
|
|
790 virtual void verify(bool allow_dirty) const;
|
|
791
|
|
792 #ifdef DEBUG
|
|
793 HeapWord* allocate(size_t size);
|
|
794 #endif
|
|
795 };
|
|
796
|
|
797 // HeapRegionClosure is used for iterating over regions.
|
|
798 // Terminates the iteration when the "doHeapRegion" method returns "true".
|
|
799 class HeapRegionClosure : public StackObj {
|
|
800 friend class HeapRegionSeq;
|
|
801 friend class G1CollectedHeap;
|
|
802
|
|
803 bool _complete;
|
|
804 void incomplete() { _complete = false; }
|
|
805
|
|
806 public:
|
|
807 HeapRegionClosure(): _complete(true) {}
|
|
808
|
|
809 // Typically called on each region until it returns true.
|
|
810 virtual bool doHeapRegion(HeapRegion* r) = 0;
|
|
811
|
|
812 // True after iteration if the closure was applied to all heap regions
|
|
813 // and returned "false" in all cases.
|
|
814 bool complete() { return _complete; }
|
|
815 };
|
|
816
|
|
817 // A linked lists of heap regions. It leaves the "next" field
|
|
818 // unspecified; that's up to subtypes.
|
|
819 class RegionList {
|
|
820 protected:
|
|
821 virtual HeapRegion* get_next(HeapRegion* chr) = 0;
|
|
822 virtual void set_next(HeapRegion* chr,
|
|
823 HeapRegion* new_next) = 0;
|
|
824
|
|
825 HeapRegion* _hd;
|
|
826 HeapRegion* _tl;
|
|
827 size_t _sz;
|
|
828
|
|
829 // Protected constructor because this type is only meaningful
|
|
830 // when the _get/_set next functions are defined.
|
|
831 RegionList() : _hd(NULL), _tl(NULL), _sz(0) {}
|
|
832 public:
|
|
833 void reset() {
|
|
834 _hd = NULL;
|
|
835 _tl = NULL;
|
|
836 _sz = 0;
|
|
837 }
|
|
838 HeapRegion* hd() { return _hd; }
|
|
839 HeapRegion* tl() { return _tl; }
|
|
840 size_t sz() { return _sz; }
|
|
841 size_t length();
|
|
842
|
|
843 bool well_formed() {
|
|
844 return
|
|
845 ((hd() == NULL && tl() == NULL && sz() == 0)
|
|
846 || (hd() != NULL && tl() != NULL && sz() > 0))
|
|
847 && (sz() == length());
|
|
848 }
|
|
849 virtual void insert_before_head(HeapRegion* r);
|
|
850 void prepend_list(RegionList* new_list);
|
|
851 virtual HeapRegion* pop();
|
|
852 void dec_sz() { _sz--; }
|
|
853 // Requires that "r" is an element of the list, and is not the tail.
|
|
854 void delete_after(HeapRegion* r);
|
|
855 };
|
|
856
|
|
857 class EmptyNonHRegionList: public RegionList {
|
|
858 protected:
|
|
859 // Protected constructor because this type is only meaningful
|
|
860 // when the _get/_set next functions are defined.
|
|
861 EmptyNonHRegionList() : RegionList() {}
|
|
862
|
|
863 public:
|
|
864 void insert_before_head(HeapRegion* r) {
|
|
865 // assert(r->is_empty(), "Better be empty");
|
|
866 assert(!r->isHumongous(), "Better not be humongous.");
|
|
867 RegionList::insert_before_head(r);
|
|
868 }
|
|
869 void prepend_list(EmptyNonHRegionList* new_list) {
|
|
870 // assert(new_list->hd() == NULL || new_list->hd()->is_empty(),
|
|
871 // "Better be empty");
|
|
872 assert(new_list->hd() == NULL || !new_list->hd()->isHumongous(),
|
|
873 "Better not be humongous.");
|
|
874 // assert(new_list->tl() == NULL || new_list->tl()->is_empty(),
|
|
875 // "Better be empty");
|
|
876 assert(new_list->tl() == NULL || !new_list->tl()->isHumongous(),
|
|
877 "Better not be humongous.");
|
|
878 RegionList::prepend_list(new_list);
|
|
879 }
|
|
880 };
|
|
881
|
|
882 class UncleanRegionList: public EmptyNonHRegionList {
|
|
883 public:
|
|
884 HeapRegion* get_next(HeapRegion* hr) {
|
|
885 return hr->next_from_unclean_list();
|
|
886 }
|
|
887 void set_next(HeapRegion* hr, HeapRegion* new_next) {
|
|
888 hr->set_next_on_unclean_list(new_next);
|
|
889 }
|
|
890
|
|
891 UncleanRegionList() : EmptyNonHRegionList() {}
|
|
892
|
|
893 void insert_before_head(HeapRegion* r) {
|
|
894 assert(!r->is_on_free_list(),
|
|
895 "Better not already be on free list");
|
|
896 assert(!r->is_on_unclean_list(),
|
|
897 "Better not already be on unclean list");
|
|
898 r->set_zero_fill_needed();
|
|
899 r->set_on_unclean_list(true);
|
|
900 EmptyNonHRegionList::insert_before_head(r);
|
|
901 }
|
|
902 void prepend_list(UncleanRegionList* new_list) {
|
|
903 assert(new_list->tl() == NULL || !new_list->tl()->is_on_free_list(),
|
|
904 "Better not already be on free list");
|
|
905 assert(new_list->tl() == NULL || new_list->tl()->is_on_unclean_list(),
|
|
906 "Better already be marked as on unclean list");
|
|
907 assert(new_list->hd() == NULL || !new_list->hd()->is_on_free_list(),
|
|
908 "Better not already be on free list");
|
|
909 assert(new_list->hd() == NULL || new_list->hd()->is_on_unclean_list(),
|
|
910 "Better already be marked as on unclean list");
|
|
911 EmptyNonHRegionList::prepend_list(new_list);
|
|
912 }
|
|
913 HeapRegion* pop() {
|
|
914 HeapRegion* res = RegionList::pop();
|
|
915 if (res != NULL) res->set_on_unclean_list(false);
|
|
916 return res;
|
|
917 }
|
|
918 };
|
|
919
|
|
920 // Local Variables: ***
|
|
921 // c-indentation-style: gnu ***
|
|
922 // End: ***
|
|
923
|
|
924 #endif // SERIALGC
|