1 /*
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  3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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  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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  9  * This code is distributed in the hope that it will be useful, but WITHOUT
 10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 12  * version 2 for more details (a copy is included in the LICENSE file that
 13  * accompanied this code).
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 19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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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/g1ConcurrentMark.inline.hpp"
 32 #include "gc/g1/heapRegionManager.inline.hpp"
 33 #include "gc/g1/heapRegionSet.inline.hpp"
 34 #include "gc/shared/taskqueue.hpp"
 35 #include "runtime/orderAccess.inline.hpp"
 36 
 37 G1EvacStats* G1CollectedHeap::alloc_buffer_stats(InCSetState dest) {
 38   switch (dest.value()) {
 39     case InCSetState::Young:
 40       return &_survivor_evac_stats;
 41     case InCSetState::Old:
 42       return &_old_evac_stats;
 43     default:
 44       ShouldNotReachHere();
 45       return NULL; // Keep some compilers happy
 46   }
 47 }
 48 
 49 size_t G1CollectedHeap::desired_plab_sz(InCSetState dest) {
 50   size_t gclab_word_size = alloc_buffer_stats(dest)->desired_plab_sz(G1CollectedHeap::heap()->workers()->active_workers());
 51   // Prevent humongous PLAB sizes for two reasons:
 52   // * PLABs are allocated using a similar paths as oops, but should
 53   //   never be in a humongous region
 54   // * Allowing humongous PLABs needlessly churns the region free lists
 55   return MIN2(_humongous_object_threshold_in_words, gclab_word_size);
 56 }
 57 
 58 // Inline functions for G1CollectedHeap
 59 
 60 // Return the region with the given index. It assumes the index is valid.
 61 inline HeapRegion* G1CollectedHeap::region_at(uint index) const { return _hrm.at(index); }
 62 
 63 inline HeapRegion* G1CollectedHeap::next_region_in_humongous(HeapRegion* hr) const {
 64   return _hrm.next_region_in_humongous(hr);
 65 }
 66 
 67 inline uint G1CollectedHeap::addr_to_region(HeapWord* addr) const {
 68   assert(is_in_reserved(addr),
 69          "Cannot calculate region index for address " PTR_FORMAT " that is outside of the heap [" PTR_FORMAT ", " PTR_FORMAT ")",
 70          p2i(addr), p2i(reserved_region().start()), p2i(reserved_region().end()));
 71   return (uint)(pointer_delta(addr, reserved_region().start(), sizeof(uint8_t)) >> HeapRegion::LogOfHRGrainBytes);
 72 }
 73 
 74 inline HeapWord* G1CollectedHeap::bottom_addr_for_region(uint index) const {
 75   return _hrm.reserved().start() + index * HeapRegion::GrainWords;
 76 }
 77 
 78 template <class T>
 79 inline HeapRegion* G1CollectedHeap::heap_region_containing(const T addr) const {
 80   assert(addr != NULL, "invariant");
 81   assert(is_in_g1_reserved((const void*) addr),
 82          "Address " PTR_FORMAT " is outside of the heap ranging from [" PTR_FORMAT " to " PTR_FORMAT ")",
 83          p2i((void*)addr), p2i(g1_reserved().start()), p2i(g1_reserved().end()));
 84   return _hrm.addr_to_region((HeapWord*) addr);
 85 }
 86 
 87 inline void G1CollectedHeap::old_set_add(HeapRegion* hr) {
 88   _old_set.add(hr);
 89 }
 90 
 91 inline void G1CollectedHeap::old_set_remove(HeapRegion* hr) {
 92   _old_set.remove(hr);
 93 }
 94 
 95 // It dirties the cards that cover the block so that the post
 96 // write barrier never queues anything when updating objects on this
 97 // block. It is assumed (and in fact we assert) that the block
 98 // belongs to a young region.
 99 inline void
100 G1CollectedHeap::dirty_young_block(HeapWord* start, size_t word_size) {
101   assert_heap_not_locked();
102 
103   // Assign the containing region to containing_hr so that we don't
104   // have to keep calling heap_region_containing() in the
105   // asserts below.
106   DEBUG_ONLY(HeapRegion* containing_hr = heap_region_containing(start);)
107   assert(word_size > 0, "pre-condition");
108   assert(containing_hr->is_in(start), "it should contain start");
109   assert(containing_hr->is_young(), "it should be young");
110   assert(!containing_hr->is_humongous(), "it should not be humongous");
111 
112   HeapWord* end = start + word_size;
113   assert(containing_hr->is_in(end - 1), "it should also contain end - 1");
114 
115   MemRegion mr(start, end);
116   card_table()->g1_mark_as_young(mr);
117 }
118 
119 inline RefToScanQueue* G1CollectedHeap::task_queue(uint i) const {
120   return _task_queues->queue(i);
121 }
122 
123 inline bool G1CollectedHeap::is_marked_next(oop obj) const {
124   return _cm->next_mark_bitmap()->is_marked((HeapWord*)obj);
125 }
126 
127 inline bool G1CollectedHeap::is_in_cset(oop obj) {
128   return is_in_cset((HeapWord*)obj);
129 }
130 
131 inline bool G1CollectedHeap::is_in_cset(HeapWord* addr) {
132   return _in_cset_fast_test.is_in_cset(addr);
133 }
134 
135 bool G1CollectedHeap::is_in_cset(const HeapRegion* hr) {
136   return _in_cset_fast_test.is_in_cset(hr);
137 }
138 
139 bool G1CollectedHeap::is_in_cset_or_humongous(const oop obj) {
140   return _in_cset_fast_test.is_in_cset_or_humongous((HeapWord*)obj);
141 }
142 
143 InCSetState G1CollectedHeap::in_cset_state(const oop obj) {
144   return _in_cset_fast_test.at((HeapWord*)obj);
145 }
146 
147 void G1CollectedHeap::register_humongous_region_with_cset(uint index) {
148   _in_cset_fast_test.set_humongous(index);
149 }
150 
151 #ifndef PRODUCT
152 // Support for G1EvacuationFailureALot
153 
154 inline bool
155 G1CollectedHeap::evacuation_failure_alot_for_gc_type(bool for_young_gc,
156                                                      bool during_initial_mark,
157                                                      bool mark_or_rebuild_in_progress) {
158   bool res = false;
159   if (mark_or_rebuild_in_progress) {
160     res |= G1EvacuationFailureALotDuringConcMark;
161   }
162   if (during_initial_mark) {
163     res |= G1EvacuationFailureALotDuringInitialMark;
164   }
165   if (for_young_gc) {
166     res |= G1EvacuationFailureALotDuringYoungGC;
167   } else {
168     // GCs are mixed
169     res |= G1EvacuationFailureALotDuringMixedGC;
170   }
171   return res;
172 }
173 
174 inline void
175 G1CollectedHeap::set_evacuation_failure_alot_for_current_gc() {
176   if (G1EvacuationFailureALot) {
177     // Note we can't assert that _evacuation_failure_alot_for_current_gc
178     // is clear here. It may have been set during a previous GC but that GC
179     // did not copy enough objects (i.e. G1EvacuationFailureALotCount) to
180     // trigger an evacuation failure and clear the flags and and counts.
181 
182     // Check if we have gone over the interval.
183     const size_t gc_num = total_collections();
184     const size_t elapsed_gcs = gc_num - _evacuation_failure_alot_gc_number;
185 
186     _evacuation_failure_alot_for_current_gc = (elapsed_gcs >= G1EvacuationFailureALotInterval);
187 
188     // Now check if G1EvacuationFailureALot is enabled for the current GC type.
189     const bool in_young_only_phase = collector_state()->in_young_only_phase();
190     const bool in_initial_mark_gc = collector_state()->in_initial_mark_gc();
191     const bool mark_or_rebuild_in_progress = collector_state()->mark_or_rebuild_in_progress();
192 
193     _evacuation_failure_alot_for_current_gc &=
194       evacuation_failure_alot_for_gc_type(in_young_only_phase,
195                                           in_initial_mark_gc,
196                                           mark_or_rebuild_in_progress);
197   }
198 }
199 
200 inline bool G1CollectedHeap::evacuation_should_fail() {
201   if (!G1EvacuationFailureALot || !_evacuation_failure_alot_for_current_gc) {
202     return false;
203   }
204   // G1EvacuationFailureALot is in effect for current GC
205   // Access to _evacuation_failure_alot_count is not atomic;
206   // the value does not have to be exact.
207   if (++_evacuation_failure_alot_count < G1EvacuationFailureALotCount) {
208     return false;
209   }
210   _evacuation_failure_alot_count = 0;
211   return true;
212 }
213 
214 inline void G1CollectedHeap::reset_evacuation_should_fail() {
215   if (G1EvacuationFailureALot) {
216     _evacuation_failure_alot_gc_number = total_collections();
217     _evacuation_failure_alot_count = 0;
218     _evacuation_failure_alot_for_current_gc = false;
219   }
220 }
221 #endif  // #ifndef PRODUCT
222 
223 inline bool G1CollectedHeap::is_in_young(const oop obj) {
224   if (obj == NULL) {
225     return false;
226   }
227   return heap_region_containing(obj)->is_young();
228 }
229 
230 inline bool G1CollectedHeap::is_obj_dead(const oop obj) const {
231   if (obj == NULL) {
232     return false;
233   }
234   return is_obj_dead(obj, heap_region_containing(obj));
235 }
236 
237 inline bool G1CollectedHeap::is_obj_ill(const oop obj) const {
238   if (obj == NULL) {
239     return false;
240   }
241   return is_obj_ill(obj, heap_region_containing(obj));
242 }
243 
244 inline bool G1CollectedHeap::is_obj_dead_full(const oop obj, const HeapRegion* hr) const {
245    return !is_marked_next(obj) && !hr->is_archive();
246 }
247 
248 inline bool G1CollectedHeap::is_obj_dead_full(const oop obj) const {
249     return is_obj_dead_full(obj, heap_region_containing(obj));
250 }
251 
252 inline void G1CollectedHeap::set_humongous_reclaim_candidate(uint region, bool value) {
253   assert(_hrm.at(region)->is_starts_humongous(), "Must start a humongous object");
254   _humongous_reclaim_candidates.set_candidate(region, value);
255 }
256 
257 inline bool G1CollectedHeap::is_humongous_reclaim_candidate(uint region) {
258   assert(_hrm.at(region)->is_starts_humongous(), "Must start a humongous object");
259   return _humongous_reclaim_candidates.is_candidate(region);
260 }
261 
262 inline void G1CollectedHeap::set_humongous_is_live(oop obj) {
263   uint region = addr_to_region((HeapWord*)obj);
264   // Clear the flag in the humongous_reclaim_candidates table.  Also
265   // reset the entry in the _in_cset_fast_test table so that subsequent references
266   // to the same humongous object do not go into the slow path again.
267   // This is racy, as multiple threads may at the same time enter here, but this
268   // is benign.
269   // During collection we only ever clear the "candidate" flag, and only ever clear the
270   // entry in the in_cset_fast_table.
271   // We only ever evaluate the contents of these tables (in the VM thread) after
272   // having synchronized the worker threads with the VM thread, or in the same
273   // thread (i.e. within the VM thread).
274   if (is_humongous_reclaim_candidate(region)) {
275     set_humongous_reclaim_candidate(region, false);
276     _in_cset_fast_test.clear_humongous(region);
277   }
278 }
279 
280 #endif // SHARE_VM_GC_G1_G1COLLECTEDHEAP_INLINE_HPP