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.
  8  *
  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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 18  *
 19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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 24 
 25 #ifndef SHARE_GC_G1_G1PARSCANTHREADSTATE_HPP
 26 #define SHARE_GC_G1_G1PARSCANTHREADSTATE_HPP
 27 
 28 #include "gc/g1/g1CardTable.hpp"
 29 #include "gc/g1/g1CollectedHeap.hpp"
 30 #include "gc/g1/g1RedirtyCardsQueue.hpp"
 31 #include "gc/g1/g1OopClosures.hpp"
 32 #include "gc/g1/g1Policy.hpp"
 33 #include "gc/g1/g1RemSet.hpp"
 34 #include "gc/g1/heapRegionRemSet.hpp"
 35 #include "gc/shared/ageTable.hpp"
 36 #include "gc/shared/taskqueue.hpp"
 37 #include "memory/allocation.hpp"
 38 #include "oops/oop.hpp"
 39 #include "utilities/ticks.hpp"
 40 
 41 class G1OopStarChunkedList;
 42 class G1PLABAllocator;
 43 class G1EvacuationRootClosures;
 44 class HeapRegion;
 45 class outputStream;
 46 
 47 class G1ParScanThreadState : public CHeapObj<mtGC> {
 48   G1CollectedHeap* _g1h;
 49   G1ScannerTasksQueue* _task_queue;
 50   G1RedirtyCardsQueue _rdcq;
 51   G1CardTable* _ct;
 52   G1EvacuationRootClosures* _closures;
 53 
 54   G1PLABAllocator* _plab_allocator;
 55 
 56   AgeTable _age_table;
 57   G1HeapRegionAttr _dest[G1HeapRegionAttr::Num];
 58   // Local tenuring threshold.
 59   uint _tenuring_threshold;
 60   G1ScanEvacuatedObjClosure  _scanner;
 61 
 62   uint _worker_id;
 63 
 64   // Remember the last enqueued card to avoid enqueuing the same card over and over;
 65   // since we only ever scan a card once, this is sufficient.
 66   size_t _last_enqueued_card;
 67 
 68   // Upper and lower threshold to start and end work queue draining.
 69   uint const _stack_trim_upper_threshold;
 70   uint const _stack_trim_lower_threshold;
 71 
 72   Tickspan _trim_ticks;
 73   // Map from young-age-index (0 == not young, 1 is youngest) to
 74   // surviving words. base is what we get back from the malloc call
 75   size_t* _surviving_young_words_base;
 76   // this points into the array, as we use the first few entries for padding
 77   size_t* _surviving_young_words;
 78   // Number of elements in the array above.
 79   size_t _surviving_words_length;
 80   // Indicates whether in the last generation (old) there is no more space
 81   // available for allocation.
 82   bool _old_gen_is_full;
 83 
 84 #define PADDING_ELEM_NUM (DEFAULT_CACHE_LINE_SIZE / sizeof(size_t))
 85 
 86   G1RedirtyCardsQueue& redirty_cards_queue()     { return _rdcq; }
 87   G1CardTable* ct()                              { return _ct; }
 88 
 89   G1HeapRegionAttr dest(G1HeapRegionAttr original) const {
 90     assert(original.is_valid(),
 91            "Original region attr invalid: %s", original.get_type_str());
 92     assert(_dest[original.type()].is_valid_gen(),
 93            "Dest region attr is invalid: %s", _dest[original.type()].get_type_str());
 94     return _dest[original.type()];
 95   }
 96 
 97   size_t _num_optional_regions;
 98   G1OopStarChunkedList* _oops_into_optional_regions;
 99 
100   G1NUMA* _numa;
101 
102   // Records how many object allocations happened at each node during copy to survivor.
103   // Only starts recording when log of gc+heap+numa is enabled and its data is
104   // transferred when flushed.
105   size_t* _obj_alloc_stat;
106 
107 public:
108   G1ParScanThreadState(G1CollectedHeap* g1h,
109                        G1RedirtyCardsQueueSet* rdcqs,
110                        uint worker_id,
111                        size_t young_cset_length,
112                        size_t optional_cset_length);
113   virtual ~G1ParScanThreadState();
114 
115   void set_ref_discoverer(ReferenceDiscoverer* rd) { _scanner.set_ref_discoverer(rd); }
116 
117 #ifdef ASSERT
118   bool queue_is_empty() const { return _task_queue->is_empty(); }
119 #endif
120 
121   void verify_task(narrowOop* task) const NOT_DEBUG_RETURN;
122   void verify_task(oop* task) const NOT_DEBUG_RETURN;
123   void verify_task(PartialArrayScanTask task) const NOT_DEBUG_RETURN;
124   void verify_task(ScannerTask task) const NOT_DEBUG_RETURN;
125 
126   void push_on_queue(ScannerTask task);
127 
128   template <class T> void enqueue_card_if_tracked(G1HeapRegionAttr region_attr, T* p, oop o) {
129     assert(!HeapRegion::is_in_same_region(p, o), "Should have filtered out cross-region references already.");
130     assert(!_g1h->heap_region_containing(p)->is_young(), "Should have filtered out from-young references already.");
131 
132 #ifdef ASSERT
133     HeapRegion* const hr_obj = _g1h->heap_region_containing(o);
134     assert(region_attr.needs_remset_update() == hr_obj->rem_set()->is_tracked(),
135            "State flag indicating remset tracking disagrees (%s) with actual remembered set (%s) for region %u",
136            BOOL_TO_STR(region_attr.needs_remset_update()),
137            BOOL_TO_STR(hr_obj->rem_set()->is_tracked()),
138            hr_obj->hrm_index());
139 #endif
140     if (!region_attr.needs_remset_update()) {
141       return;
142     }
143     size_t card_index = ct()->index_for(p);
144     // If the card hasn't been added to the buffer, do it.
145     if (_last_enqueued_card != card_index) {
146       redirty_cards_queue().enqueue(ct()->byte_for_index(card_index));
147       _last_enqueued_card = card_index;
148     }
149   }
150 
151   G1EvacuationRootClosures* closures() { return _closures; }
152   uint worker_id() { return _worker_id; }
153 
154   size_t lab_waste_words() const;
155   size_t lab_undo_waste_words() const;
156 
157   // Pass locally gathered statistics to global state. Returns the total number of
158   // HeapWords copied.
159   size_t flush(size_t* surviving_young_words);
160 
161 private:
162   inline void do_partial_array(PartialArrayScanTask task);
163 
164   // This method is applied to the fields of the objects that have just been copied.
165   template <class T> inline void do_oop_evac(T* p);
166 
167   inline void dispatch_task(ScannerTask task);
168 
169   // Tries to allocate word_sz in the PLAB of the next "generation" after trying to
170   // allocate into dest. Previous_plab_refill_failed indicates whether previous
171   // PLAB refill for the original (source) object failed.
172   // Returns a non-NULL pointer if successful, and updates dest if required.
173   // Also determines whether we should continue to try to allocate into the various
174   // generations or just end trying to allocate.
175   HeapWord* allocate_in_next_plab(G1HeapRegionAttr* dest,
176                                   size_t word_sz,
177                                   bool previous_plab_refill_failed,
178                                   uint node_index);
179 
180   inline G1HeapRegionAttr next_region_attr(G1HeapRegionAttr const region_attr, markWord const m, uint& age);
181 
182   void report_promotion_event(G1HeapRegionAttr const dest_attr,
183                               oop const old, size_t word_sz, uint age,
184                               HeapWord * const obj_ptr, uint node_index) const;
185 
186   inline bool needs_partial_trimming() const;
187   inline bool is_partially_trimmed() const;
188 
189   inline void trim_queue_to_threshold(uint threshold);
190 
191   // NUMA statistics related methods.
192   inline void initialize_numa_stats();
193   inline void flush_numa_stats();
194   inline void update_numa_stats(uint node_index);
195 
196 public:
197   oop copy_to_survivor_space(G1HeapRegionAttr const region_attr, oop const obj, markWord const old_mark);
198 
199   void trim_queue();
200   void trim_queue_partially();
201 
202   Tickspan trim_ticks() const;
203   void reset_trim_ticks();
204 
205   inline void steal_and_trim_queue(G1ScannerTasksQueueSet *task_queues);
206 
207   // An attempt to evacuate "obj" has failed; take necessary steps.
208   oop handle_evacuation_failure_par(oop obj, markWord m);
209 
210   template <typename T>
211   inline void remember_root_into_optional_region(T* p);
212   template <typename T>
213   inline void remember_reference_into_optional_region(T* p);
214 
215   inline G1OopStarChunkedList* oops_into_optional_region(const HeapRegion* hr);
216 };
217 
218 class G1ParScanThreadStateSet : public StackObj {
219   G1CollectedHeap* _g1h;
220   G1RedirtyCardsQueueSet* _rdcqs;
221   G1ParScanThreadState** _states;
222   size_t* _surviving_young_words_total;
223   size_t _young_cset_length;
224   size_t _optional_cset_length;
225   uint _n_workers;
226   bool _flushed;
227 
228  public:
229   G1ParScanThreadStateSet(G1CollectedHeap* g1h,
230                           G1RedirtyCardsQueueSet* rdcqs,
231                           uint n_workers,
232                           size_t young_cset_length,
233                           size_t optional_cset_length);
234   ~G1ParScanThreadStateSet();
235 
236   void flush();
237   void record_unused_optional_region(HeapRegion* hr);
238 
239   G1ParScanThreadState* state_for_worker(uint worker_id);
240 
241   const size_t* surviving_young_words() const;
242 
243  private:
244   G1ParScanThreadState* new_par_scan_state(uint worker_id, size_t young_cset_length);
245 };
246 
247 #endif // SHARE_GC_G1_G1PARSCANTHREADSTATE_HPP