1 /*
   2  * Copyright (c) 2014, 2020, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   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.
   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  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
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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/g1RemSet.hpp"
  33 #include "gc/g1/heapRegionRemSet.hpp"
  34 #include "gc/shared/ageTable.hpp"
  35 #include "gc/shared/taskqueue.hpp"
  36 #include "memory/allocation.hpp"
  37 #include "oops/oop.hpp"
  38 #include "utilities/ticks.hpp"
  39 
  40 class G1OopStarChunkedList;
  41 class G1PLABAllocator;
  42 class G1EvacuationRootClosures;
  43 class HeapRegion;
  44 class outputStream;
  45 
  46 class G1ParScanThreadState : public CHeapObj<mtGC> {
  47   G1CollectedHeap* _g1h;
  48   G1ScannerTasksQueue* _task_queue;
  49   G1RedirtyCardsQueue _rdcq;
  50   G1CardTable* _ct;
  51   G1EvacuationRootClosures* _closures;
  52 
  53   G1PLABAllocator* _plab_allocator;
  54 
  55   AgeTable _age_table;
  56   G1HeapRegionAttr _dest[G1HeapRegionAttr::Num];
  57   // Local tenuring threshold.
  58   uint _tenuring_threshold;
  59   G1ScanEvacuatedObjClosure  _scanner;
  60 
  61   uint _worker_id;
  62 
  63   // Remember the last enqueued card to avoid enqueuing the same card over and over;
  64   // since we only ever scan a card once, this is sufficient.
  65   size_t _last_enqueued_card;
  66 
  67   // Upper and lower threshold to start and end work queue draining.
  68   uint const _stack_trim_upper_threshold;
  69   uint const _stack_trim_lower_threshold;
  70 
  71   Tickspan _trim_ticks;
  72   // Map from young-age-index (0 == not young, 1 is youngest) to
  73   // surviving words. base is what we get back from the malloc call
  74   size_t* _surviving_young_words_base;
  75   // this points into the array, as we use the first few entries for padding
  76   size_t* _surviving_young_words;
  77   // Number of elements in the array above.
  78   size_t _surviving_words_length;
  79   // Indicates whether in the last generation (old) there is no more space
  80   // available for allocation.
  81   bool _old_gen_is_full;
  82 
  83   G1RedirtyCardsQueue& redirty_cards_queue()     { return _rdcq; }
  84   G1CardTable* ct()                              { return _ct; }
  85 
  86   G1HeapRegionAttr dest(G1HeapRegionAttr original) const {
  87     assert(original.is_valid(),
  88            "Original region attr invalid: %s", original.get_type_str());
  89     assert(_dest[original.type()].is_valid_gen(),
  90            "Dest region attr is invalid: %s", _dest[original.type()].get_type_str());
  91     return _dest[original.type()];
  92   }
  93 
  94   size_t _num_optional_regions;
  95   G1OopStarChunkedList* _oops_into_optional_regions;
  96 
  97   G1NUMA* _numa;
  98 
  99   // Records how many object allocations happened at each node during copy to survivor.
 100   // Only starts recording when log of gc+heap+numa is enabled and its data is
 101   // transferred when flushed.
 102   size_t* _obj_alloc_stat;
 103 
 104 public:
 105   G1ParScanThreadState(G1CollectedHeap* g1h,
 106                        G1RedirtyCardsQueueSet* rdcqs,
 107                        uint worker_id,
 108                        size_t young_cset_length,
 109                        size_t optional_cset_length);
 110   virtual ~G1ParScanThreadState();
 111 
 112   void set_ref_discoverer(ReferenceDiscoverer* rd) { _scanner.set_ref_discoverer(rd); }
 113 
 114 #ifdef ASSERT
 115   bool queue_is_empty() const { return _task_queue->is_empty(); }
 116 #endif
 117 
 118   void verify_task(narrowOop* task) const NOT_DEBUG_RETURN;
 119   void verify_task(oop* task) const NOT_DEBUG_RETURN;
 120   void verify_task(PartialArrayScanTask task) const NOT_DEBUG_RETURN;
 121   void verify_task(ScannerTask task) const NOT_DEBUG_RETURN;
 122 
 123   void push_on_queue(ScannerTask task);
 124 
 125   template <class T> void enqueue_card_if_tracked(G1HeapRegionAttr region_attr, T* p, oop o) {
 126     assert(!HeapRegion::is_in_same_region(p, o), "Should have filtered out cross-region references already.");
 127     assert(!_g1h->heap_region_containing(p)->is_young(), "Should have filtered out from-young references already.");
 128 
 129 #ifdef ASSERT
 130     HeapRegion* const hr_obj = _g1h->heap_region_containing(o);
 131     assert(region_attr.needs_remset_update() == hr_obj->rem_set()->is_tracked(),
 132            "State flag indicating remset tracking disagrees (%s) with actual remembered set (%s) for region %u",
 133            BOOL_TO_STR(region_attr.needs_remset_update()),
 134            BOOL_TO_STR(hr_obj->rem_set()->is_tracked()),
 135            hr_obj->hrm_index());
 136 #endif
 137     if (!region_attr.needs_remset_update()) {
 138       return;
 139     }
 140     size_t card_index = ct()->index_for(p);
 141     // If the card hasn't been added to the buffer, do it.
 142     if (_last_enqueued_card != card_index) {
 143       redirty_cards_queue().enqueue(ct()->byte_for_index(card_index));
 144       _last_enqueued_card = card_index;
 145     }
 146   }
 147 
 148   G1EvacuationRootClosures* closures() { return _closures; }
 149   uint worker_id() { return _worker_id; }
 150 
 151   size_t lab_waste_words() const;
 152   size_t lab_undo_waste_words() const;
 153 
 154   // Pass locally gathered statistics to global state. Returns the total number of
 155   // HeapWords copied.
 156   size_t flush(size_t* surviving_young_words);
 157 
 158 private:
 159   inline void do_partial_array(PartialArrayScanTask task);
 160 
 161   HeapWord* allocate_copy_slow(G1HeapRegionAttr* dest_attr,
 162                                oop old,
 163                                size_t word_sz,
 164                                uint age,
 165                                uint node_index);
 166 
 167   void undo_allocation(G1HeapRegionAttr dest_addr,
 168                        HeapWord* obj_ptr,
 169                        size_t word_sz,
 170                        uint node_index);
 171 
 172   inline oop do_copy_to_survivor_space(G1HeapRegionAttr region_attr,
 173                                        oop obj,
 174                                        markWord old_mark);
 175 
 176   // This method is applied to the fields of the objects that have just been copied.
 177   template <class T> inline void do_oop_evac(T* p);
 178 
 179   inline void dispatch_task(ScannerTask task);
 180 
 181   // Tries to allocate word_sz in the PLAB of the next "generation" after trying to
 182   // allocate into dest. Previous_plab_refill_failed indicates whether previous
 183   // PLAB refill for the original (source) object failed.
 184   // Returns a non-NULL pointer if successful, and updates dest if required.
 185   // Also determines whether we should continue to try to allocate into the various
 186   // generations or just end trying to allocate.
 187   HeapWord* allocate_in_next_plab(G1HeapRegionAttr* dest,
 188                                   size_t word_sz,
 189                                   bool previous_plab_refill_failed,
 190                                   uint node_index);
 191 
 192   inline G1HeapRegionAttr next_region_attr(G1HeapRegionAttr const region_attr, markWord const m, uint& age);
 193 
 194   void report_promotion_event(G1HeapRegionAttr const dest_attr,
 195                               oop const old, size_t word_sz, uint age,
 196                               HeapWord * const obj_ptr, uint node_index) const;
 197 
 198   void trim_queue_to_threshold(uint threshold);
 199 
 200   inline bool needs_partial_trimming() const;
 201 
 202   // NUMA statistics related methods.
 203   void initialize_numa_stats();
 204   void flush_numa_stats();
 205   inline void update_numa_stats(uint node_index);
 206 
 207 public:
 208   oop copy_to_survivor_space(G1HeapRegionAttr region_attr, oop obj, markWord old_mark);
 209 
 210   inline void trim_queue();
 211   inline void trim_queue_partially();
 212   void steal_and_trim_queue(G1ScannerTasksQueueSet *task_queues);
 213 
 214   Tickspan trim_ticks() const;
 215   void reset_trim_ticks();
 216 
 217   // An attempt to evacuate "obj" has failed; take necessary steps.
 218   oop handle_evacuation_failure_par(oop obj, markWord m);
 219 
 220   template <typename T>
 221   inline void remember_root_into_optional_region(T* p);
 222   template <typename T>
 223   inline void remember_reference_into_optional_region(T* p);
 224 
 225   inline G1OopStarChunkedList* oops_into_optional_region(const HeapRegion* hr);
 226 };
 227 
 228 class G1ParScanThreadStateSet : public StackObj {
 229   G1CollectedHeap* _g1h;
 230   G1RedirtyCardsQueueSet* _rdcqs;
 231   G1ParScanThreadState** _states;
 232   size_t* _surviving_young_words_total;
 233   size_t _young_cset_length;
 234   size_t _optional_cset_length;
 235   uint _n_workers;
 236   bool _flushed;
 237 
 238  public:
 239   G1ParScanThreadStateSet(G1CollectedHeap* g1h,
 240                           G1RedirtyCardsQueueSet* rdcqs,
 241                           uint n_workers,
 242                           size_t young_cset_length,
 243                           size_t optional_cset_length);
 244   ~G1ParScanThreadStateSet();
 245 
 246   void flush();
 247   void record_unused_optional_region(HeapRegion* hr);
 248 
 249   G1ParScanThreadState* state_for_worker(uint worker_id);
 250 
 251   const size_t* surviving_young_words() const;
 252 
 253  private:
 254   G1ParScanThreadState* new_par_scan_state(uint worker_id, size_t young_cset_length);
 255 };
 256 
 257 #endif // SHARE_GC_G1_G1PARSCANTHREADSTATE_HPP