1 /*
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   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
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  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
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  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
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  20  * or visit www.oracle.com if you need additional information or have any
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  24 
  25 #ifndef SHARE_VM_GC_G1_G1COLLECTEDHEAP_INLINE_HPP
  26 #define SHARE_VM_GC_G1_G1COLLECTEDHEAP_INLINE_HPP
  27 
  28 #include "gc/g1/g1BarrierSet.hpp"
  29 #include "gc/g1/g1CollectedHeap.hpp"
  30 #include "gc/g1/g1CollectorState.hpp"
  31 #include "gc/g1/heapRegionManager.inline.hpp"
  32 #include "gc/g1/heapRegionSet.inline.hpp"
  33 #include "gc/shared/taskqueue.inline.hpp"
  34 #include "runtime/orderAccess.hpp"
  35 
  36 G1EvacStats* G1CollectedHeap::alloc_buffer_stats(InCSetState dest) {
  37   switch (dest.value()) {
  38     case InCSetState::Young:
  39       return &_survivor_evac_stats;
  40     case InCSetState::Old:
  41       return &_old_evac_stats;
  42     default:
  43       ShouldNotReachHere();
  44       return NULL; // Keep some compilers happy
  45   }
  46 }
  47 
  48 size_t G1CollectedHeap::desired_plab_sz(InCSetState dest) {
  49   size_t gclab_word_size = alloc_buffer_stats(dest)->desired_plab_sz(workers()->active_workers());
  50   // Prevent humongous PLAB sizes for two reasons:
  51   // * PLABs are allocated using a similar paths as oops, but should
  52   //   never be in a humongous region
  53   // * Allowing humongous PLABs needlessly churns the region free lists
  54   return MIN2(_humongous_object_threshold_in_words, gclab_word_size);
  55 }
  56 
  57 // Inline functions for G1CollectedHeap
  58 
  59 // Return the region with the given index. It assumes the index is valid.
  60 inline HeapRegion* G1CollectedHeap::region_at(uint index) const { return _hrm.at(index); }
  61 
  62 inline HeapRegion* G1CollectedHeap::next_region_in_humongous(HeapRegion* hr) const {
  63   return _hrm.next_region_in_humongous(hr);
  64 }
  65 
  66 inline uint G1CollectedHeap::addr_to_region(HeapWord* addr) const {
  67   assert(is_in_reserved(addr),
  68          "Cannot calculate region index for address " PTR_FORMAT " that is outside of the heap [" PTR_FORMAT ", " PTR_FORMAT ")",
  69          p2i(addr), p2i(reserved_region().start()), p2i(reserved_region().end()));
  70   return (uint)(pointer_delta(addr, reserved_region().start(), sizeof(uint8_t)) >> HeapRegion::LogOfHRGrainBytes);
  71 }
  72 
  73 inline HeapWord* G1CollectedHeap::bottom_addr_for_region(uint index) const {
  74   return _hrm.reserved().start() + index * HeapRegion::GrainWords;
  75 }
  76 
  77 template <class T>
  78 inline HeapRegion* G1CollectedHeap::heap_region_containing(const T addr) const {
  79   assert(addr != NULL, "invariant");
  80   assert(is_in_g1_reserved((const void*) addr),
  81          "Address " PTR_FORMAT " is outside of the heap ranging from [" PTR_FORMAT " to " PTR_FORMAT ")",
  82          p2i((void*)addr), p2i(g1_reserved().start()), p2i(g1_reserved().end()));
  83   return _hrm.addr_to_region((HeapWord*) addr);
  84 }
  85 
  86 inline void G1CollectedHeap::old_set_add(HeapRegion* hr) {
  87   _old_set.add(hr);
  88 }
  89 
  90 inline void G1CollectedHeap::old_set_remove(HeapRegion* hr) {
  91   _old_set.remove(hr);
  92 }
  93 
  94 // It dirties the cards that cover the block so that the post
  95 // write barrier never queues anything when updating objects on this
  96 // block. It is assumed (and in fact we assert) that the block
  97 // belongs to a young region.
  98 inline void
  99 G1CollectedHeap::dirty_young_block(HeapWord* start, size_t word_size) {
 100   assert_heap_not_locked();
 101 
 102   // Assign the containing region to containing_hr so that we don't
 103   // have to keep calling heap_region_containing() in the
 104   // asserts below.
 105   DEBUG_ONLY(HeapRegion* containing_hr = heap_region_containing(start);)
 106   assert(word_size > 0, "pre-condition");
 107   assert(containing_hr->is_in(start), "it should contain start");
 108   assert(containing_hr->is_young(), "it should be young");
 109   assert(!containing_hr->is_humongous(), "it should not be humongous");
 110 
 111   HeapWord* end = start + word_size;
 112   assert(containing_hr->is_in(end - 1), "it should also contain end - 1");
 113 
 114   MemRegion mr(start, end);
 115   card_table()->g1_mark_as_young(mr);
 116 }
 117 
 118 inline RefToScanQueue* G1CollectedHeap::task_queue(uint i) const {
 119   return _task_queues->queue(i);
 120 }
 121 
 122 inline bool G1CollectedHeap::is_marked_next(oop obj) const {
 123   return _cm->next_mark_bitmap()->is_marked((HeapWord*)obj);
 124 }
 125 
 126 inline bool G1CollectedHeap::is_in_cset(oop obj) {
 127   return is_in_cset((HeapWord*)obj);
 128 }
 129 
 130 inline bool G1CollectedHeap::is_in_cset(HeapWord* addr) {
 131   return _in_cset_fast_test.is_in_cset(addr);
 132 }
 133 
 134 bool G1CollectedHeap::is_in_cset(const HeapRegion* hr) {
 135   return _in_cset_fast_test.is_in_cset(hr);
 136 }
 137 
 138 bool G1CollectedHeap::is_in_cset_or_humongous(const oop obj) {
 139   return _in_cset_fast_test.is_in_cset_or_humongous((HeapWord*)obj);
 140 }
 141 
 142 InCSetState G1CollectedHeap::in_cset_state(const oop obj) {
 143   return _in_cset_fast_test.at((HeapWord*)obj);
 144 }
 145 
 146 void G1CollectedHeap::register_humongous_region_with_cset(uint index) {
 147   _in_cset_fast_test.set_humongous(index);
 148 }
 149 
 150 #ifndef PRODUCT
 151 // Support for G1EvacuationFailureALot
 152 
 153 inline bool
 154 G1CollectedHeap::evacuation_failure_alot_for_gc_type(bool for_young_gc,
 155                                                      bool during_initial_mark,
 156                                                      bool mark_or_rebuild_in_progress) {
 157   bool res = false;
 158   if (mark_or_rebuild_in_progress) {
 159     res |= G1EvacuationFailureALotDuringConcMark;
 160   }
 161   if (during_initial_mark) {
 162     res |= G1EvacuationFailureALotDuringInitialMark;
 163   }
 164   if (for_young_gc) {
 165     res |= G1EvacuationFailureALotDuringYoungGC;
 166   } else {
 167     // GCs are mixed
 168     res |= G1EvacuationFailureALotDuringMixedGC;
 169   }
 170   return res;
 171 }
 172 
 173 inline void
 174 G1CollectedHeap::set_evacuation_failure_alot_for_current_gc() {
 175   if (G1EvacuationFailureALot) {
 176     // Note we can't assert that _evacuation_failure_alot_for_current_gc
 177     // is clear here. It may have been set during a previous GC but that GC
 178     // did not copy enough objects (i.e. G1EvacuationFailureALotCount) to
 179     // trigger an evacuation failure and clear the flags and and counts.
 180 
 181     // Check if we have gone over the interval.
 182     const size_t gc_num = total_collections();
 183     const size_t elapsed_gcs = gc_num - _evacuation_failure_alot_gc_number;
 184 
 185     _evacuation_failure_alot_for_current_gc = (elapsed_gcs >= G1EvacuationFailureALotInterval);
 186 
 187     // Now check if G1EvacuationFailureALot is enabled for the current GC type.
 188     const bool in_young_only_phase = collector_state()->in_young_only_phase();
 189     const bool in_initial_mark_gc = collector_state()->in_initial_mark_gc();
 190     const bool mark_or_rebuild_in_progress = collector_state()->mark_or_rebuild_in_progress();
 191 
 192     _evacuation_failure_alot_for_current_gc &=
 193       evacuation_failure_alot_for_gc_type(in_young_only_phase,
 194                                           in_initial_mark_gc,
 195                                           mark_or_rebuild_in_progress);
 196   }
 197 }
 198 
 199 inline bool G1CollectedHeap::evacuation_should_fail() {
 200   if (!G1EvacuationFailureALot || !_evacuation_failure_alot_for_current_gc) {
 201     return false;
 202   }
 203   // G1EvacuationFailureALot is in effect for current GC
 204   // Access to _evacuation_failure_alot_count is not atomic;
 205   // the value does not have to be exact.
 206   if (++_evacuation_failure_alot_count < G1EvacuationFailureALotCount) {
 207     return false;
 208   }
 209   _evacuation_failure_alot_count = 0;
 210   return true;
 211 }
 212 
 213 inline void G1CollectedHeap::reset_evacuation_should_fail() {
 214   if (G1EvacuationFailureALot) {
 215     _evacuation_failure_alot_gc_number = total_collections();
 216     _evacuation_failure_alot_count = 0;
 217     _evacuation_failure_alot_for_current_gc = false;
 218   }
 219 }
 220 #endif  // #ifndef PRODUCT
 221 
 222 inline bool G1CollectedHeap::is_in_young(const oop obj) {
 223   if (obj == NULL) {
 224     return false;
 225   }
 226   return heap_region_containing(obj)->is_young();
 227 }
 228 
 229 inline bool G1CollectedHeap::is_obj_dead(const oop obj) const {
 230   if (obj == NULL) {
 231     return false;
 232   }
 233   return is_obj_dead(obj, heap_region_containing(obj));
 234 }
 235 
 236 inline bool G1CollectedHeap::is_obj_ill(const oop obj) const {
 237   if (obj == NULL) {
 238     return false;
 239   }
 240   return is_obj_ill(obj, heap_region_containing(obj));
 241 }
 242 
 243 inline bool G1CollectedHeap::is_obj_dead_full(const oop obj, const HeapRegion* hr) const {
 244    return !is_marked_next(obj) && !hr->is_archive();
 245 }
 246 
 247 inline bool G1CollectedHeap::is_obj_dead_full(const oop obj) const {
 248     return is_obj_dead_full(obj, heap_region_containing(obj));
 249 }
 250 
 251 inline void G1CollectedHeap::set_humongous_reclaim_candidate(uint region, bool value) {
 252   assert(_hrm.at(region)->is_starts_humongous(), "Must start a humongous object");
 253   _humongous_reclaim_candidates.set_candidate(region, value);
 254 }
 255 
 256 inline bool G1CollectedHeap::is_humongous_reclaim_candidate(uint region) {
 257   assert(_hrm.at(region)->is_starts_humongous(), "Must start a humongous object");
 258   return _humongous_reclaim_candidates.is_candidate(region);
 259 }
 260 
 261 inline void G1CollectedHeap::set_humongous_is_live(oop obj) {
 262   uint region = addr_to_region((HeapWord*)obj);
 263   // Clear the flag in the humongous_reclaim_candidates table.  Also
 264   // reset the entry in the _in_cset_fast_test table so that subsequent references
 265   // to the same humongous object do not go into the slow path again.
 266   // This is racy, as multiple threads may at the same time enter here, but this
 267   // is benign.
 268   // During collection we only ever clear the "candidate" flag, and only ever clear the
 269   // entry in the in_cset_fast_table.
 270   // We only ever evaluate the contents of these tables (in the VM thread) after
 271   // having synchronized the worker threads with the VM thread, or in the same
 272   // thread (i.e. within the VM thread).
 273   if (is_humongous_reclaim_candidate(region)) {
 274     set_humongous_reclaim_candidate(region, false);
 275     _in_cset_fast_test.clear_humongous(region);
 276   }
 277 }
 278 
 279 #endif // SHARE_VM_GC_G1_G1COLLECTEDHEAP_INLINE_HPP