1 /*
   2  * Copyright (c) 2014, 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
  21  * questions.
  22  *
  23  */
  24 
  25 #ifndef SHARE_VM_GC_IMPLEMENTATION_G1_G1PARSCANTHREADSTATE_HPP
  26 #define SHARE_VM_GC_IMPLEMENTATION_G1_G1PARSCANTHREADSTATE_HPP
  27 
  28 #include "gc_implementation/g1/dirtyCardQueue.hpp"
  29 #include "gc_implementation/g1/g1SATBCardTableModRefBS.hpp"
  30 #include "gc_implementation/g1/g1CollectedHeap.hpp"
  31 #include "gc_implementation/g1/g1CollectorPolicy.hpp"
  32 #include "gc_implementation/g1/g1OopClosures.hpp"
  33 #include "gc_implementation/g1/g1RemSet.hpp"
  34 #include "gc_implementation/shared/ageTable.hpp"
  35 #include "memory/allocation.hpp"
  36 #include "oops/oop.hpp"
  37 
  38 class HeapRegion;
  39 class outputStream;
  40 
  41 class G1ParScanThreadState : public StackObj {
  42  private:
  43   G1CollectedHeap* _g1h;
  44   RefToScanQueue*  _refs;
  45   DirtyCardQueue   _dcq;
  46   G1SATBCardTableModRefBS* _ct_bs;
  47   G1RemSet* _g1_rem;
  48 
  49   G1ParGCAllocBuffer  _surviving_alloc_buffer;
  50   G1ParGCAllocBuffer  _tenured_alloc_buffer;
  51   G1ParGCAllocBuffer* _alloc_buffers[GCAllocPurposeCount];
  52   ageTable            _age_table;
  53 
  54   G1ParScanClosure    _scanner;
  55 
  56   size_t           _alloc_buffer_waste;
  57   size_t           _undo_waste;
  58 
  59   OopsInHeapRegionClosure*      _evac_failure_cl;
  60 
  61   int  _hash_seed;
  62   uint _queue_num;
  63 
  64   size_t _term_attempts;
  65 
  66   double _start;
  67   double _start_strong_roots;
  68   double _strong_roots_time;
  69   double _start_term;
  70   double _term_time;
  71 
  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 
  78 #define PADDING_ELEM_NUM (DEFAULT_CACHE_LINE_SIZE / sizeof(size_t))
  79 
  80   void   add_to_alloc_buffer_waste(size_t waste) { _alloc_buffer_waste += waste; }
  81 
  82   void   add_to_undo_waste(size_t waste)         { _undo_waste += waste; }
  83 
  84   DirtyCardQueue& dirty_card_queue()             { return _dcq;  }
  85   G1SATBCardTableModRefBS* ctbs()                { return _ct_bs; }
  86 
  87   template <class T> inline void immediate_rs_update(HeapRegion* from, T* p, int tid);
  88 
  89   template <class T> void deferred_rs_update(HeapRegion* from, T* p, int tid) {
  90     // If the new value of the field points to the same region or
  91     // is the to-space, we don't need to include it in the Rset updates.
  92     if (!from->is_in_reserved(oopDesc::load_decode_heap_oop(p)) && !from->is_survivor()) {
  93       size_t card_index = ctbs()->index_for(p);
  94       // If the card hasn't been added to the buffer, do it.
  95       if (ctbs()->mark_card_deferred(card_index)) {
  96         dirty_card_queue().enqueue((jbyte*)ctbs()->byte_for_index(card_index));
  97       }
  98     }
  99   }
 100 
 101 public:
 102   G1ParScanThreadState(G1CollectedHeap* g1h, uint queue_num, ReferenceProcessor* rp);
 103   ~G1ParScanThreadState() {
 104     retire_alloc_buffers();
 105     FREE_C_HEAP_ARRAY(size_t, _surviving_young_words_base, mtGC);
 106   }
 107 
 108   RefToScanQueue*   refs()            { return _refs;             }
 109   ageTable*         age_table()       { return &_age_table;       }
 110 
 111   G1ParGCAllocBuffer* alloc_buffer(GCAllocPurpose purpose) {
 112     return _alloc_buffers[purpose];
 113   }
 114 
 115   size_t alloc_buffer_waste() const              { return _alloc_buffer_waste; }
 116   size_t undo_waste() const                      { return _undo_waste; }
 117 
 118  public:
 119   G1ParScanThreadState(G1CollectedHeap* g1h, uint queue_num, ReferenceProcessor* rp);
 120   ~G1ParScanThreadState();
 121 
 122   ageTable*         age_table()       { return &_age_table;       }
 123 
 124 #ifdef ASSERT
 125   bool queue_is_empty() const { return _refs->is_empty(); }
 126 
 127   bool verify_ref(narrowOop* ref) const;
 128   bool verify_ref(oop* ref) const;
 129   bool verify_task(StarTask ref) const;
 130 #endif // ASSERT
 131 
 132   template <class T> void push_on_queue(T* ref) {
 133     assert(verify_ref(ref), "sanity");
 134     _refs->push(ref);
 135   }
 136 
 137   template <class T> inline void update_rs(HeapRegion* from, T* p, int tid);
 138 
 139  private:
 140 
 141   HeapWord* allocate(GCAllocPurpose purpose, size_t word_sz);
 142   HeapWord* allocate_slow(GCAllocPurpose purpose, size_t word_sz);
 143   void undo_allocation(GCAllocPurpose purpose, HeapWord* obj, size_t word_sz);
 144 
 145  public:
 146 
 147   void set_evac_failure_closure(OopsInHeapRegionClosure* evac_failure_cl) {
 148     _evac_failure_cl = evac_failure_cl;
 149   }
 150 
 151   OopsInHeapRegionClosure* evac_failure_closure() { return _evac_failure_cl; }
 152 
 153   int* hash_seed() { return &_hash_seed; }
 154   uint queue_num() { return _queue_num; }
 155 
 156   size_t term_attempts() const  { return _term_attempts; }
 157   void note_term_attempt() { _term_attempts++; }
 158 
 159   void start_strong_roots() {
 160     _start_strong_roots = os::elapsedTime();
 161   }
 162   void end_strong_roots() {
 163     _strong_roots_time += (os::elapsedTime() - _start_strong_roots);
 164   }
 165   double strong_roots_time() const { return _strong_roots_time; }
 166 
 167   void start_term_time() {
 168     note_term_attempt();
 169     _start_term = os::elapsedTime();
 170   }
 171   void end_term_time() {
 172     _term_time += (os::elapsedTime() - _start_term);
 173   }
 174   double term_time() const { return _term_time; }
 175 
 176   double elapsed_time() const {
 177     return os::elapsedTime() - _start;
 178   }
 179 
 180   static void print_termination_stats_hdr(outputStream* const st = gclog_or_tty);
 181   void print_termination_stats(int i, outputStream* const st = gclog_or_tty) const;
 182 
 183   size_t* surviving_young_words() {
 184     // We add on to hide entry 0 which accumulates surviving words for
 185     // age -1 regions (i.e. non-young ones)
 186     return _surviving_young_words;
 187   }
 188 
 189  private:
 190   void retire_alloc_buffers();
 191 
 192   #define G1_PARTIAL_ARRAY_MASK 0x2
 193 
 194   inline bool has_partial_array_mask(oop* ref) const {
 195     return ((uintptr_t)ref & G1_PARTIAL_ARRAY_MASK) == G1_PARTIAL_ARRAY_MASK;
 196   }
 197 
 198   // We never encode partial array oops as narrowOop*, so return false immediately.
 199   // This allows the compiler to create optimized code when popping references from
 200   // the work queue.
 201   inline bool has_partial_array_mask(narrowOop* ref) const {
 202     assert(((uintptr_t)ref & G1_PARTIAL_ARRAY_MASK) != G1_PARTIAL_ARRAY_MASK, "Partial array oop reference encoded as narrowOop*");
 203     return false;
 204   }
 205 
 206   // Only implement set_partial_array_mask() for regular oops, not for narrowOops.
 207   // We always encode partial arrays as regular oop, to allow the
 208   // specialization for has_partial_array_mask() for narrowOops above.
 209   // This means that unintentional use of this method with narrowOops are caught
 210   // by the compiler.
 211   inline oop* set_partial_array_mask(oop obj) const {
 212     assert(((uintptr_t)(void *)obj & G1_PARTIAL_ARRAY_MASK) == 0, "Information loss!");
 213     return (oop*) ((uintptr_t)(void *)obj | G1_PARTIAL_ARRAY_MASK);
 214   }
 215 
 216   inline oop clear_partial_array_mask(oop* ref) const {
 217     return cast_to_oop((intptr_t)ref & ~G1_PARTIAL_ARRAY_MASK);
 218   }
 219 
 220   inline void do_oop_partial_array(oop* p);
 221 
 222   // This method is applied to the fields of the objects that have just been copied.
 223   template <class T> void do_oop_evac(T* p, HeapRegion* from);
 224 
 225   template <class T> inline void deal_with_reference(T* ref_to_scan);
 226 
 227   inline void deal_with_reference(StarTask ref);
 228 public:
 229 
 230   oop copy_to_survivor_space(oop const obj);
 231 
 232   void trim_queue();
 233 
 234   void steal_and_trim_queue(RefToScanQueueSet *task_queues);
 235 };
 236 
 237 #endif // SHARE_VM_GC_IMPLEMENTATION_G1_G1PARSCANTHREADSTATE_HPP