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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  9  * This code is distributed in the hope that it will be useful, but WITHOUT
 10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 12  * version 2 for more details (a copy is included in the LICENSE file that
 13  * accompanied this code).
 14  *
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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/g1CollectedHeap.hpp"
 29 #include "gc/g1/g1CollectorState.hpp"
 30 #include "gc/g1/g1ConcurrentMark.inline.hpp"
 31 #include "gc/g1/g1SATBCardTableModRefBS.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::reset_gc_time_stamp() {
 88   assert_at_safepoint(true);
 89   _gc_time_stamp = 0;
 90 }
 91 
 92 inline void G1CollectedHeap::increment_gc_time_stamp() {
 93   assert_at_safepoint(true);
 94   ++_gc_time_stamp;
 95 }
 96 
 97 inline void G1CollectedHeap::old_set_add(HeapRegion* hr) {
 98   _old_set.add(hr);
 99 }
100 
101 inline void G1CollectedHeap::old_set_remove(HeapRegion* hr) {
102   _old_set.remove(hr);
103 }
104 
105 // It dirties the cards that cover the block so that the post
106 // write barrier never queues anything when updating objects on this
107 // block. It is assumed (and in fact we assert) that the block
108 // belongs to a young region.
109 inline void
110 G1CollectedHeap::dirty_young_block(HeapWord* start, size_t word_size) {
111   assert_heap_not_locked();
112 
113   // Assign the containing region to containing_hr so that we don't
114   // have to keep calling heap_region_containing() in the
115   // asserts below.
116   DEBUG_ONLY(HeapRegion* containing_hr = heap_region_containing(start);)
117   assert(word_size > 0, "pre-condition");
118   assert(containing_hr->is_in(start), "it should contain start");
119   assert(containing_hr->is_young(), "it should be young");
120   assert(!containing_hr->is_humongous(), "it should not be humongous");
121 
122   HeapWord* end = start + word_size;
123   assert(containing_hr->is_in(end - 1), "it should also contain end - 1");
124 
125   MemRegion mr(start, end);
126   card_table()->g1_mark_as_young(mr);
127 }
128 
129 inline RefToScanQueue* G1CollectedHeap::task_queue(uint i) const {
130   return _task_queues->queue(i);
131 }
132 
133 inline bool G1CollectedHeap::isMarkedNext(oop obj) const {
134   return _cm->next_mark_bitmap()->is_marked((HeapWord*)obj);
135 }
136 
137 inline bool G1CollectedHeap::is_in_cset(oop obj) {
138   return is_in_cset((HeapWord*)obj);
139 }
140 
141 inline bool G1CollectedHeap::is_in_cset(HeapWord* addr) {
142   return _in_cset_fast_test.is_in_cset(addr);
143 }
144 
145 bool G1CollectedHeap::is_in_cset(const HeapRegion* hr) {
146   return _in_cset_fast_test.is_in_cset(hr);
147 }
148 
149 bool G1CollectedHeap::is_in_cset_or_humongous(const oop obj) {
150   return _in_cset_fast_test.is_in_cset_or_humongous((HeapWord*)obj);
151 }
152 
153 InCSetState G1CollectedHeap::in_cset_state(const oop obj) {
154   return _in_cset_fast_test.at((HeapWord*)obj);
155 }
156 
157 void G1CollectedHeap::register_humongous_region_with_cset(uint index) {
158   _in_cset_fast_test.set_humongous(index);
159 }
160 
161 #ifndef PRODUCT
162 // Support for G1EvacuationFailureALot
163 
164 inline bool
165 G1CollectedHeap::evacuation_failure_alot_for_gc_type(bool gcs_are_young,
166                                                      bool during_initial_mark,
167                                                      bool during_marking) {
168   bool res = false;
169   if (during_marking) {
170     res |= G1EvacuationFailureALotDuringConcMark;
171   }
172   if (during_initial_mark) {
173     res |= G1EvacuationFailureALotDuringInitialMark;
174   }
175   if (gcs_are_young) {
176     res |= G1EvacuationFailureALotDuringYoungGC;
177   } else {
178     // GCs are mixed
179     res |= G1EvacuationFailureALotDuringMixedGC;
180   }
181   return res;
182 }
183 
184 inline void
185 G1CollectedHeap::set_evacuation_failure_alot_for_current_gc() {
186   if (G1EvacuationFailureALot) {
187     // Note we can't assert that _evacuation_failure_alot_for_current_gc
188     // is clear here. It may have been set during a previous GC but that GC
189     // did not copy enough objects (i.e. G1EvacuationFailureALotCount) to
190     // trigger an evacuation failure and clear the flags and and counts.
191 
192     // Check if we have gone over the interval.
193     const size_t gc_num = total_collections();
194     const size_t elapsed_gcs = gc_num - _evacuation_failure_alot_gc_number;
195 
196     _evacuation_failure_alot_for_current_gc = (elapsed_gcs >= G1EvacuationFailureALotInterval);
197 
198     // Now check if G1EvacuationFailureALot is enabled for the current GC type.
199     const bool gcs_are_young = collector_state()->gcs_are_young();
200     const bool during_im = collector_state()->during_initial_mark_pause();
201     const bool during_marking = collector_state()->mark_in_progress();
202 
203     _evacuation_failure_alot_for_current_gc &=
204       evacuation_failure_alot_for_gc_type(gcs_are_young,
205                                           during_im,
206                                           during_marking);
207   }
208 }
209 
210 inline bool G1CollectedHeap::evacuation_should_fail() {
211   if (!G1EvacuationFailureALot || !_evacuation_failure_alot_for_current_gc) {
212     return false;
213   }
214   // G1EvacuationFailureALot is in effect for current GC
215   // Access to _evacuation_failure_alot_count is not atomic;
216   // the value does not have to be exact.
217   if (++_evacuation_failure_alot_count < G1EvacuationFailureALotCount) {
218     return false;
219   }
220   _evacuation_failure_alot_count = 0;
221   return true;
222 }
223 
224 inline void G1CollectedHeap::reset_evacuation_should_fail() {
225   if (G1EvacuationFailureALot) {
226     _evacuation_failure_alot_gc_number = total_collections();
227     _evacuation_failure_alot_count = 0;
228     _evacuation_failure_alot_for_current_gc = false;
229   }
230 }
231 #endif  // #ifndef PRODUCT
232 
233 inline bool G1CollectedHeap::is_in_young(const oop obj) {
234   if (obj == NULL) {
235     return false;
236   }
237   return heap_region_containing(obj)->is_young();
238 }
239 
240 inline bool G1CollectedHeap::is_obj_dead(const oop obj) const {
241   if (obj == NULL) {
242     return false;
243   }
244   return is_obj_dead(obj, heap_region_containing(obj));
245 }
246 
247 inline bool G1CollectedHeap::is_obj_ill(const oop obj) const {
248   if (obj == NULL) {
249     return false;
250   }
251   return is_obj_ill(obj, heap_region_containing(obj));
252 }
253 
254 inline bool G1CollectedHeap::is_obj_dead_full(const oop obj, const HeapRegion* hr) const {
255    return !isMarkedNext(obj) && !hr->is_archive();
256 }
257 
258 inline bool G1CollectedHeap::is_obj_dead_full(const oop obj) const {
259     return is_obj_dead_full(obj, heap_region_containing(obj));
260 }
261 
262 inline void G1CollectedHeap::set_humongous_reclaim_candidate(uint region, bool value) {
263   assert(_hrm.at(region)->is_starts_humongous(), "Must start a humongous object");
264   _humongous_reclaim_candidates.set_candidate(region, value);
265 }
266 
267 inline bool G1CollectedHeap::is_humongous_reclaim_candidate(uint region) {
268   assert(_hrm.at(region)->is_starts_humongous(), "Must start a humongous object");
269   return _humongous_reclaim_candidates.is_candidate(region);
270 }
271 
272 inline void G1CollectedHeap::set_humongous_is_live(oop obj) {
273   uint region = addr_to_region((HeapWord*)obj);
274   // Clear the flag in the humongous_reclaim_candidates table.  Also
275   // reset the entry in the _in_cset_fast_test table so that subsequent references
276   // to the same humongous object do not go into the slow path again.
277   // This is racy, as multiple threads may at the same time enter here, but this
278   // is benign.
279   // During collection we only ever clear the "candidate" flag, and only ever clear the
280   // entry in the in_cset_fast_table.
281   // We only ever evaluate the contents of these tables (in the VM thread) after
282   // having synchronized the worker threads with the VM thread, or in the same
283   // thread (i.e. within the VM thread).
284   if (is_humongous_reclaim_candidate(region)) {
285     set_humongous_reclaim_candidate(region, false);
286     _in_cset_fast_test.clear_humongous(region);
287   }
288 }
289 
290 #endif // SHARE_VM_GC_G1_G1COLLECTEDHEAP_INLINE_HPP