rev 52676 : imported patch AMGC-impl
rev 52677 : imported patch AMGC-tsch-rev1

   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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  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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  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
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  20  * or visit www.oracle.com if you need additional information or have any
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  24 
  25 #ifndef SHARE_VM_GC_G1_HEAPREGION_HPP
  26 #define SHARE_VM_GC_G1_HEAPREGION_HPP
  27 
  28 #include "gc/g1/g1BlockOffsetTable.hpp"
  29 #include "gc/g1/g1HeapRegionTraceType.hpp"
  30 #include "gc/g1/heapRegionTracer.hpp"
  31 #include "gc/g1/heapRegionType.hpp"
  32 #include "gc/g1/survRateGroup.hpp"
  33 #include "gc/shared/ageTable.hpp"
  34 #include "gc/shared/cardTable.hpp"
  35 #include "gc/shared/spaceDecorator.hpp"
  36 #include "utilities/macros.hpp"
  37 
  38 // A HeapRegion is the smallest piece of a G1CollectedHeap that
  39 // can be collected independently.
  40 
  41 // NOTE: Although a HeapRegion is a Space, its
  42 // Space::initDirtyCardClosure method must not be called.
  43 // The problem is that the existence of this method breaks
  44 // the independence of barrier sets from remembered sets.
  45 // The solution is to remove this method from the definition
  46 // of a Space.
  47 
  48 // Each heap region is self contained. top() and end() can never
  49 // be set beyond the end of the region. For humongous objects,
  50 // the first region is a StartsHumongous region. If the humongous
  51 // object is larger than a heap region, the following regions will
  52 // be of type ContinuesHumongous. In this case the top() of the
  53 // StartHumongous region and all ContinuesHumongous regions except
  54 // the last will point to their own end. The last ContinuesHumongous
  55 // region may have top() equal the end of object if there isn't
  56 // room for filler objects to pad out to the end of the region.
  57 
  58 class G1CollectedHeap;
  59 class G1CMBitMap;
  60 class G1IsAliveAndApplyClosure;
  61 class HeapRegionRemSet;
  62 class HeapRegionRemSetIterator;
  63 class HeapRegion;
  64 class HeapRegionSetBase;
  65 class nmethod;
  66 
  67 #define HR_FORMAT "%u:(%s)[" PTR_FORMAT "," PTR_FORMAT "," PTR_FORMAT "]"
  68 #define HR_FORMAT_PARAMS(_hr_) \
  69                 (_hr_)->hrm_index(), \
  70                 (_hr_)->get_short_type_str(), \
  71                 p2i((_hr_)->bottom()), p2i((_hr_)->top()), p2i((_hr_)->end())
  72 
  73 // sentinel value for hrm_index
  74 #define G1_NO_HRM_INDEX ((uint) -1)
  75 
  76 // The complicating factor is that BlockOffsetTable diverged
  77 // significantly, and we need functionality that is only in the G1 version.
  78 // So I copied that code, which led to an alternate G1 version of
  79 // OffsetTableContigSpace.  If the two versions of BlockOffsetTable could
  80 // be reconciled, then G1OffsetTableContigSpace could go away.
  81 
  82 // The idea behind time stamps is the following. We want to keep track of
  83 // the highest address where it's safe to scan objects for each region.
  84 // This is only relevant for current GC alloc regions so we keep a time stamp
  85 // per region to determine if the region has been allocated during the current
  86 // GC or not. If the time stamp is current we report a scan_top value which
  87 // was saved at the end of the previous GC for retained alloc regions and which is
  88 // equal to the bottom for all other regions.
  89 // There is a race between card scanners and allocating gc workers where we must ensure
  90 // that card scanners do not read the memory allocated by the gc workers.
  91 // In order to enforce that, we must not return a value of _top which is more recent than the
  92 // time stamp. This is due to the fact that a region may become a gc alloc region at
  93 // some point after we've read the timestamp value as being < the current time stamp.
  94 // The time stamps are re-initialized to zero at cleanup and at Full GCs.
  95 // The current scheme that uses sequential unsigned ints will fail only if we have 4b
  96 // evacuation pauses between two cleanups, which is _highly_ unlikely.
  97 class G1ContiguousSpace: public CompactibleSpace {
  98   friend class VMStructs;
  99   HeapWord* volatile _top;
 100  protected:
 101   G1BlockOffsetTablePart _bot_part;
 102   Mutex _par_alloc_lock;
 103   // When we need to retire an allocation region, while other threads
 104   // are also concurrently trying to allocate into it, we typically
 105   // allocate a dummy object at the end of the region to ensure that
 106   // no more allocations can take place in it. However, sometimes we
 107   // want to know where the end of the last "real" object we allocated
 108   // into the region was and this is what this keeps track.
 109   HeapWord* _pre_dummy_top;
 110 
 111  public:
 112   G1ContiguousSpace(G1BlockOffsetTable* bot);
 113 
 114   void set_top(HeapWord* value) { _top = value; }
 115   HeapWord* top() const { return _top; }
 116 
 117  protected:
 118   // Reset the G1ContiguousSpace.
 119   virtual void initialize(MemRegion mr, bool clear_space, bool mangle_space);
 120 
 121   HeapWord* volatile* top_addr() { return &_top; }
 122   // Try to allocate at least min_word_size and up to desired_size from this Space.
 123   // Returns NULL if not possible, otherwise sets actual_word_size to the amount of
 124   // space allocated.
 125   // This version assumes that all allocation requests to this Space are properly
 126   // synchronized.
 127   inline HeapWord* allocate_impl(size_t min_word_size, size_t desired_word_size, size_t* actual_word_size);
 128   // Try to allocate at least min_word_size and up to desired_size from this Space.
 129   // Returns NULL if not possible, otherwise sets actual_word_size to the amount of
 130   // space allocated.
 131   // This version synchronizes with other calls to par_allocate_impl().
 132   inline HeapWord* par_allocate_impl(size_t min_word_size, size_t desired_word_size, size_t* actual_word_size);
 133 
 134  public:
 135   void reset_after_compaction() { set_top(compaction_top()); }
 136 
 137   size_t used() const { return byte_size(bottom(), top()); }
 138   size_t free() const { return byte_size(top(), end()); }
 139   bool is_free_block(const HeapWord* p) const { return p >= top(); }
 140 
 141   MemRegion used_region() const { return MemRegion(bottom(), top()); }
 142 
 143   void object_iterate(ObjectClosure* blk);
 144   void safe_object_iterate(ObjectClosure* blk);
 145 
 146   void mangle_unused_area() PRODUCT_RETURN;
 147   void mangle_unused_area_complete() PRODUCT_RETURN;
 148 
 149   // See the comment above in the declaration of _pre_dummy_top for an
 150   // explanation of what it is.
 151   void set_pre_dummy_top(HeapWord* pre_dummy_top) {
 152     assert(is_in(pre_dummy_top) && pre_dummy_top <= top(), "pre-condition");
 153     _pre_dummy_top = pre_dummy_top;
 154   }
 155   HeapWord* pre_dummy_top() {
 156     return (_pre_dummy_top == NULL) ? top() : _pre_dummy_top;
 157   }
 158   void reset_pre_dummy_top() { _pre_dummy_top = NULL; }
 159 
 160   virtual void clear(bool mangle_space);
 161 
 162   HeapWord* block_start(const void* p);
 163   HeapWord* block_start_const(const void* p) const;
 164 
 165   // Allocation (return NULL if full).  Assumes the caller has established
 166   // mutually exclusive access to the space.
 167   HeapWord* allocate(size_t min_word_size, size_t desired_word_size, size_t* actual_word_size);
 168   // Allocation (return NULL if full).  Enforces mutual exclusion internally.
 169   HeapWord* par_allocate(size_t min_word_size, size_t desired_word_size, size_t* actual_word_size);
 170 
 171   virtual HeapWord* allocate(size_t word_size);
 172   virtual HeapWord* par_allocate(size_t word_size);
 173 
 174   HeapWord* saved_mark_word() const { ShouldNotReachHere(); return NULL; }
 175 
 176   // MarkSweep support phase3
 177   virtual HeapWord* initialize_threshold();
 178   virtual HeapWord* cross_threshold(HeapWord* start, HeapWord* end);
 179 
 180   virtual void print() const;
 181 
 182   void reset_bot() {
 183     _bot_part.reset_bot();
 184   }
 185 
 186   void print_bot_on(outputStream* out) {
 187     _bot_part.print_on(out);
 188   }
 189 };
 190 
 191 class HeapRegion: public G1ContiguousSpace {
 192   friend class VMStructs;
 193   // Allow scan_and_forward to call (private) overrides for auxiliary functions on this class
 194   template <typename SpaceType>
 195   friend void CompactibleSpace::scan_and_forward(SpaceType* space, CompactPoint* cp);
 196  private:
 197 
 198   // The remembered set for this region.
 199   // (Might want to make this "inline" later, to avoid some alloc failure
 200   // issues.)
 201   HeapRegionRemSet* _rem_set;
 202 
 203   // Auxiliary functions for scan_and_forward support.
 204   // See comments for CompactibleSpace for more information.
 205   inline HeapWord* scan_limit() const {
 206     return top();
 207   }
 208 
 209   inline bool scanned_block_is_obj(const HeapWord* addr) const {
 210     return true; // Always true, since scan_limit is top
 211   }
 212 
 213   inline size_t scanned_block_size(const HeapWord* addr) const {
 214     return HeapRegion::block_size(addr); // Avoid virtual call
 215   }
 216 
 217   void report_region_type_change(G1HeapRegionTraceType::Type to);
 218 
 219   // Returns whether the given object address refers to a dead object, and either the
 220   // size of the object (if live) or the size of the block (if dead) in size.
 221   // May
 222   // - only called with obj < top()
 223   // - not called on humongous objects or archive regions
 224   inline bool is_obj_dead_with_size(const oop obj, const G1CMBitMap* const prev_bitmap, size_t* size) const;
 225 
 226  protected:
 227   // The index of this region in the heap region sequence.
 228   uint  _hrm_index;
 229 
 230   HeapRegionType _type;
 231 
 232   // For a humongous region, region in which it starts.
 233   HeapRegion* _humongous_start_region;
 234 
 235   // True iff an attempt to evacuate an object in the region failed.
 236   bool _evacuation_failed;
 237 
 238   // Fields used by the HeapRegionSetBase class and subclasses.
 239   HeapRegion* _next;
 240   HeapRegion* _prev;
 241 #ifdef ASSERT
 242   HeapRegionSetBase* _containing_set;
 243 #endif // ASSERT
 244 
 245   // We use concurrent marking to determine the amount of live data
 246   // in each heap region.
 247   size_t _prev_marked_bytes;    // Bytes known to be live via last completed marking.
 248   size_t _next_marked_bytes;    // Bytes known to be live via in-progress marking.
 249 
 250   // The calculated GC efficiency of the region.
 251   double _gc_efficiency;
 252 
 253   // The index in the optional regions array, if this region
 254   // is considered optional during a mixed collections.
 255   uint _index_in_opt_cset;
 256   int  _young_index_in_cset;
 257   SurvRateGroup* _surv_rate_group;
 258   int  _age_index;
 259 
 260   // The start of the unmarked area. The unmarked area extends from this
 261   // word until the top and/or end of the region, and is the part
 262   // of the region for which no marking was done, i.e. objects may
 263   // have been allocated in this part since the last mark phase.
 264   // "prev" is the top at the start of the last completed marking.
 265   // "next" is the top at the start of the in-progress marking (if any.)
 266   HeapWord* _prev_top_at_mark_start;
 267   HeapWord* _next_top_at_mark_start;
 268   // If a collection pause is in progress, this is the top at the start
 269   // of that pause.
 270 
 271   void init_top_at_mark_start() {
 272     assert(_prev_marked_bytes == 0 &&
 273            _next_marked_bytes == 0,
 274            "Must be called after zero_marked_bytes.");
 275     HeapWord* bot = bottom();
 276     _prev_top_at_mark_start = bot;
 277     _next_top_at_mark_start = bot;
 278   }
 279 
 280   // Cached attributes used in the collection set policy information
 281 
 282   // The RSet length that was added to the total value
 283   // for the collection set.
 284   size_t _recorded_rs_length;
 285 
 286   // The predicted elapsed time that was added to total value
 287   // for the collection set.
 288   double _predicted_elapsed_time_ms;
 289 
 290   // Iterate over the references in a humongous objects and apply the given closure
 291   // to them.
 292   // Humongous objects are allocated directly in the old-gen. So we need special
 293   // handling for concurrent processing encountering an in-progress allocation.
 294   template <class Closure, bool is_gc_active>
 295   inline bool do_oops_on_card_in_humongous(MemRegion mr,
 296                                            Closure* cl,
 297                                            G1CollectedHeap* g1h);
 298 
 299   // Returns the block size of the given (dead, potentially having its class unloaded) object
 300   // starting at p extending to at most the prev TAMS using the given mark bitmap.
 301   inline size_t block_size_using_bitmap(const HeapWord* p, const G1CMBitMap* const prev_bitmap) const;
 302  public:
 303   HeapRegion(uint hrm_index,
 304              G1BlockOffsetTable* bot,
 305              MemRegion mr);
 306 
 307   // Initializing the HeapRegion not only resets the data structure, but also
 308   // resets the BOT for that heap region.
 309   // The default values for clear_space means that we will do the clearing if
 310   // there's clearing to be done ourselves. We also always mangle the space.
 311   virtual void initialize(MemRegion mr, bool clear_space = false, bool mangle_space = SpaceDecorator::Mangle);
 312 
 313   static int    LogOfHRGrainBytes;
 314   static int    LogOfHRGrainWords;
 315 
 316   static size_t GrainBytes;
 317   static size_t GrainWords;
 318   static size_t CardsPerRegion;
 319 
 320   static size_t align_up_to_region_byte_size(size_t sz) {
 321     return (sz + (size_t) GrainBytes - 1) &
 322                                       ~((1 << (size_t) LogOfHRGrainBytes) - 1);
 323   }
 324 
 325 
 326   // Returns whether a field is in the same region as the obj it points to.
 327   template <typename T>
 328   static bool is_in_same_region(T* p, oop obj) {
 329     assert(p != NULL, "p can't be NULL");
 330     assert(obj != NULL, "obj can't be NULL");
 331     return (((uintptr_t) p ^ cast_from_oop<uintptr_t>(obj)) >> LogOfHRGrainBytes) == 0;
 332   }
 333 
 334   static size_t max_region_size();
 335   static size_t min_region_size_in_words();
 336 
 337   // It sets up the heap region size (GrainBytes / GrainWords), as
 338   // well as other related fields that are based on the heap region
 339   // size (LogOfHRGrainBytes / LogOfHRGrainWords /
 340   // CardsPerRegion). All those fields are considered constant
 341   // throughout the JVM's execution, therefore they should only be set
 342   // up once during initialization time.
 343   static void setup_heap_region_size(size_t initial_heap_size, size_t max_heap_size);
 344 
 345   // All allocated blocks are occupied by objects in a HeapRegion
 346   bool block_is_obj(const HeapWord* p) const;
 347 
 348   // Returns whether the given object is dead based on TAMS and bitmap.
 349   bool is_obj_dead(const oop obj, const G1CMBitMap* const prev_bitmap) const;
 350 
 351   // Returns the object size for all valid block starts
 352   // and the amount of unallocated words if called on top()
 353   size_t block_size(const HeapWord* p) const;
 354 
 355   // Scans through the region using the bitmap to determine what
 356   // objects to call size_t ApplyToMarkedClosure::apply(oop) for.
 357   template<typename ApplyToMarkedClosure>
 358   inline void apply_to_marked_objects(G1CMBitMap* bitmap, ApplyToMarkedClosure* closure);
 359   // Override for scan_and_forward support.
 360   void prepare_for_compaction(CompactPoint* cp);
 361   // Update heap region to be consistent after compaction.
 362   void complete_compaction();
 363 
 364   inline HeapWord* par_allocate_no_bot_updates(size_t min_word_size, size_t desired_word_size, size_t* word_size);
 365   inline HeapWord* allocate_no_bot_updates(size_t word_size);
 366   inline HeapWord* allocate_no_bot_updates(size_t min_word_size, size_t desired_word_size, size_t* actual_size);
 367 
 368   // If this region is a member of a HeapRegionManager, the index in that
 369   // sequence, otherwise -1.
 370   uint hrm_index() const { return _hrm_index; }
 371 
 372   // The number of bytes marked live in the region in the last marking phase.
 373   size_t marked_bytes()    { return _prev_marked_bytes; }
 374   size_t live_bytes() {
 375     return (top() - prev_top_at_mark_start()) * HeapWordSize + marked_bytes();
 376   }
 377 
 378   // The number of bytes counted in the next marking.
 379   size_t next_marked_bytes() { return _next_marked_bytes; }
 380   // The number of bytes live wrt the next marking.
 381   size_t next_live_bytes() {
 382     return
 383       (top() - next_top_at_mark_start()) * HeapWordSize + next_marked_bytes();
 384   }
 385 
 386   // A lower bound on the amount of garbage bytes in the region.
 387   size_t garbage_bytes() {
 388     size_t used_at_mark_start_bytes =
 389       (prev_top_at_mark_start() - bottom()) * HeapWordSize;
 390     return used_at_mark_start_bytes - marked_bytes();
 391   }
 392 
 393   // Return the amount of bytes we'll reclaim if we collect this
 394   // region. This includes not only the known garbage bytes in the
 395   // region but also any unallocated space in it, i.e., [top, end),
 396   // since it will also be reclaimed if we collect the region.
 397   size_t reclaimable_bytes() {
 398     size_t known_live_bytes = live_bytes();
 399     assert(known_live_bytes <= capacity(), "sanity");
 400     return capacity() - known_live_bytes;
 401   }
 402 
 403   // An upper bound on the number of live bytes in the region.
 404   size_t max_live_bytes() { return used() - garbage_bytes(); }
 405 
 406   void add_to_marked_bytes(size_t incr_bytes) {
 407     _next_marked_bytes = _next_marked_bytes + incr_bytes;
 408   }
 409 
 410   void zero_marked_bytes()      {
 411     _prev_marked_bytes = _next_marked_bytes = 0;
 412   }
 413 
 414   const char* get_type_str() const { return _type.get_str(); }
 415   const char* get_short_type_str() const { return _type.get_short_str(); }
 416   G1HeapRegionTraceType::Type get_trace_type() { return _type.get_trace_type(); }
 417 
 418   bool is_free() const { return _type.is_free(); }
 419 
 420   bool is_young()    const { return _type.is_young();    }
 421   bool is_eden()     const { return _type.is_eden();     }
 422   bool is_survivor() const { return _type.is_survivor(); }
 423 
 424   bool is_humongous() const { return _type.is_humongous(); }
 425   bool is_starts_humongous() const { return _type.is_starts_humongous(); }
 426   bool is_continues_humongous() const { return _type.is_continues_humongous();   }
 427 
 428   bool is_old() const { return _type.is_old(); }
 429 
 430   bool is_old_or_humongous() const { return _type.is_old_or_humongous(); }
 431 
 432   bool is_old_or_humongous_or_archive() const { return _type.is_old_or_humongous_or_archive(); }
 433 
 434   // A pinned region contains objects which are not moved by garbage collections.
 435   // Humongous regions and archive regions are pinned.
 436   bool is_pinned() const { return _type.is_pinned(); }
 437 
 438   // An archive region is a pinned region, also tagged as old, which
 439   // should not be marked during mark/sweep. This allows the address
 440   // space to be shared by JVM instances.
 441   bool is_archive()        const { return _type.is_archive(); }
 442   bool is_open_archive()   const { return _type.is_open_archive(); }
 443   bool is_closed_archive() const { return _type.is_closed_archive(); }
 444 
 445   // For a humongous region, region in which it starts.
 446   HeapRegion* humongous_start_region() const {
 447     return _humongous_start_region;
 448   }
 449 
 450   // Makes the current region be a "starts humongous" region, i.e.,
 451   // the first region in a series of one or more contiguous regions
 452   // that will contain a single "humongous" object.
 453   //
 454   // obj_top : points to the top of the humongous object.
 455   // fill_size : size of the filler object at the end of the region series.
 456   void set_starts_humongous(HeapWord* obj_top, size_t fill_size);
 457 
 458   // Makes the current region be a "continues humongous'
 459   // region. first_hr is the "start humongous" region of the series
 460   // which this region will be part of.
 461   void set_continues_humongous(HeapRegion* first_hr);
 462 
 463   // Unsets the humongous-related fields on the region.
 464   void clear_humongous();
 465 
 466   // If the region has a remembered set, return a pointer to it.
 467   HeapRegionRemSet* rem_set() const {
 468     return _rem_set;
 469   }
 470 
 471   inline bool in_collection_set() const;
 472 
 473   // Methods used by the HeapRegionSetBase class and subclasses.
 474 
 475   // Getter and setter for the next and prev fields used to link regions into
 476   // linked lists.
 477   HeapRegion* next()              { return _next; }
 478   HeapRegion* prev()              { return _prev; }
 479 
 480   void set_next(HeapRegion* next) { _next = next; }
 481   void set_prev(HeapRegion* prev) { _prev = prev; }
 482 
 483   // Every region added to a set is tagged with a reference to that
 484   // set. This is used for doing consistency checking to make sure that
 485   // the contents of a set are as they should be and it's only
 486   // available in non-product builds.
 487 #ifdef ASSERT
 488   void set_containing_set(HeapRegionSetBase* containing_set) {
 489     assert((containing_set == NULL && _containing_set != NULL) ||
 490            (containing_set != NULL && _containing_set == NULL),
 491            "containing_set: " PTR_FORMAT " "
 492            "_containing_set: " PTR_FORMAT,
 493            p2i(containing_set), p2i(_containing_set));
 494 
 495     _containing_set = containing_set;
 496   }
 497 
 498   HeapRegionSetBase* containing_set() { return _containing_set; }
 499 #else // ASSERT
 500   void set_containing_set(HeapRegionSetBase* containing_set) { }
 501 
 502   // containing_set() is only used in asserts so there's no reason
 503   // to provide a dummy version of it.
 504 #endif // ASSERT
 505 
 506 
 507   // Reset the HeapRegion to default values.
 508   // If skip_remset is true, do not clear the remembered set.
 509   // If clear_space is true, clear the HeapRegion's memory.
 510   // If locked is true, assume we are the only thread doing this operation.
 511   void hr_clear(bool skip_remset, bool clear_space, bool locked = false);
 512   // Clear the card table corresponding to this region.
 513   void clear_cardtable();
 514 
 515   // Get the start of the unmarked area in this region.
 516   HeapWord* prev_top_at_mark_start() const { return _prev_top_at_mark_start; }
 517   HeapWord* next_top_at_mark_start() const { return _next_top_at_mark_start; }
 518 
 519   // Note the start or end of marking. This tells the heap region
 520   // that the collector is about to start or has finished (concurrently)
 521   // marking the heap.
 522 
 523   // Notify the region that concurrent marking is starting. Initialize
 524   // all fields related to the next marking info.
 525   inline void note_start_of_marking();
 526 
 527   // Notify the region that concurrent marking has finished. Copy the
 528   // (now finalized) next marking info fields into the prev marking
 529   // info fields.
 530   inline void note_end_of_marking();
 531 
 532   // Notify the region that it will be used as to-space during a GC
 533   // and we are about to start copying objects into it.
 534   inline void note_start_of_copying(bool during_initial_mark);
 535 
 536   // Notify the region that it ceases being to-space during a GC and
 537   // we will not copy objects into it any more.
 538   inline void note_end_of_copying(bool during_initial_mark);
 539 
 540   // Notify the region that we are about to start processing
 541   // self-forwarded objects during evac failure handling.
 542   void note_self_forwarding_removal_start(bool during_initial_mark,
 543                                           bool during_conc_mark);
 544 
 545   // Notify the region that we have finished processing self-forwarded
 546   // objects during evac failure handling.
 547   void note_self_forwarding_removal_end(size_t marked_bytes);
 548 
 549   void reset_during_compaction() {
 550     assert(is_humongous(),
 551            "should only be called for humongous regions");
 552 
 553     zero_marked_bytes();
 554     init_top_at_mark_start();
 555   }
 556 
 557   void calc_gc_efficiency(void);
 558   double gc_efficiency() { return _gc_efficiency;}
 559 
 560   uint index_in_opt_cset() const { return _index_in_opt_cset; }
 561   void set_index_in_opt_cset(uint index) { _index_in_opt_cset = index; }
 562 
 563   int  young_index_in_cset() const { return _young_index_in_cset; }
 564   void set_young_index_in_cset(int index) {
 565     assert( (index == -1) || is_young(), "pre-condition" );
 566     _young_index_in_cset = index;
 567   }
 568 
 569   int age_in_surv_rate_group() {
 570     assert( _surv_rate_group != NULL, "pre-condition" );
 571     assert( _age_index > -1, "pre-condition" );
 572     return _surv_rate_group->age_in_group(_age_index);
 573   }
 574 
 575   void record_surv_words_in_group(size_t words_survived) {
 576     assert( _surv_rate_group != NULL, "pre-condition" );
 577     assert( _age_index > -1, "pre-condition" );
 578     int age_in_group = age_in_surv_rate_group();
 579     _surv_rate_group->record_surviving_words(age_in_group, words_survived);
 580   }
 581 
 582   int age_in_surv_rate_group_cond() {
 583     if (_surv_rate_group != NULL)
 584       return age_in_surv_rate_group();
 585     else
 586       return -1;
 587   }
 588 
 589   SurvRateGroup* surv_rate_group() {
 590     return _surv_rate_group;
 591   }
 592 
 593   void install_surv_rate_group(SurvRateGroup* surv_rate_group) {
 594     assert( surv_rate_group != NULL, "pre-condition" );
 595     assert( _surv_rate_group == NULL, "pre-condition" );
 596     assert( is_young(), "pre-condition" );
 597 
 598     _surv_rate_group = surv_rate_group;
 599     _age_index = surv_rate_group->next_age_index();
 600   }
 601 
 602   void uninstall_surv_rate_group() {
 603     if (_surv_rate_group != NULL) {
 604       assert( _age_index > -1, "pre-condition" );
 605       assert( is_young(), "pre-condition" );
 606 
 607       _surv_rate_group = NULL;
 608       _age_index = -1;
 609     } else {
 610       assert( _age_index == -1, "pre-condition" );
 611     }
 612   }
 613 
 614   void set_free();
 615 
 616   void set_eden();
 617   void set_eden_pre_gc();
 618   void set_survivor();
 619 
 620   void move_to_old();
 621   void set_old();
 622 
 623   void set_open_archive();
 624   void set_closed_archive();
 625 
 626   // Determine if an object has been allocated since the last
 627   // mark performed by the collector. This returns true iff the object
 628   // is within the unmarked area of the region.
 629   bool obj_allocated_since_prev_marking(oop obj) const {
 630     return (HeapWord *) obj >= prev_top_at_mark_start();
 631   }
 632   bool obj_allocated_since_next_marking(oop obj) const {
 633     return (HeapWord *) obj >= next_top_at_mark_start();
 634   }
 635 
 636   // Returns the "evacuation_failed" property of the region.
 637   bool evacuation_failed() { return _evacuation_failed; }
 638 
 639   // Sets the "evacuation_failed" property of the region.
 640   void set_evacuation_failed(bool b) {
 641     _evacuation_failed = b;
 642 
 643     if (b) {
 644       _next_marked_bytes = 0;
 645     }
 646   }
 647 
 648   // Iterate over the objects overlapping part of a card, applying cl
 649   // to all references in the region.  This is a helper for
 650   // G1RemSet::refine_card*, and is tightly coupled with them.
 651   // mr is the memory region covered by the card, trimmed to the
 652   // allocated space for this region.  Must not be empty.
 653   // This region must be old or humongous.
 654   // Returns true if the designated objects were successfully
 655   // processed, false if an unparsable part of the heap was
 656   // encountered; that only happens when invoked concurrently with the
 657   // mutator.
 658   template <bool is_gc_active, class Closure>
 659   inline bool oops_on_card_seq_iterate_careful(MemRegion mr, Closure* cl);
 660 
 661   size_t recorded_rs_length() const        { return _recorded_rs_length; }
 662   double predicted_elapsed_time_ms() const { return _predicted_elapsed_time_ms; }
 663 
 664   void set_recorded_rs_length(size_t rs_length) {
 665     _recorded_rs_length = rs_length;
 666   }
 667 
 668   void set_predicted_elapsed_time_ms(double ms) {
 669     _predicted_elapsed_time_ms = ms;
 670   }
 671 
 672   // Routines for managing a list of code roots (attached to the
 673   // this region's RSet) that point into this heap region.
 674   void add_strong_code_root(nmethod* nm);
 675   void add_strong_code_root_locked(nmethod* nm);
 676   void remove_strong_code_root(nmethod* nm);
 677 
 678   // Applies blk->do_code_blob() to each of the entries in
 679   // the strong code roots list for this region
 680   void strong_code_roots_do(CodeBlobClosure* blk) const;
 681 
 682   // Verify that the entries on the strong code root list for this
 683   // region are live and include at least one pointer into this region.
 684   void verify_strong_code_roots(VerifyOption vo, bool* failures) const;
 685 
 686   void print() const;
 687   void print_on(outputStream* st) const;
 688 
 689   // vo == UsePrevMarking -> use "prev" marking information,
 690   // vo == UseNextMarking -> use "next" marking information
 691   // vo == UseFullMarking -> use "next" marking bitmap but no TAMS
 692   //
 693   // NOTE: Only the "prev" marking information is guaranteed to be
 694   // consistent most of the time, so most calls to this should use
 695   // vo == UsePrevMarking.
 696   // Currently, there is only one case where this is called with
 697   // vo == UseNextMarking, which is to verify the "next" marking
 698   // information at the end of remark.
 699   // Currently there is only one place where this is called with
 700   // vo == UseFullMarking, which is to verify the marking during a
 701   // full GC.
 702   void verify(VerifyOption vo, bool *failures) const;
 703 
 704   // Override; it uses the "prev" marking information
 705   virtual void verify() const;
 706 
 707   void verify_rem_set(VerifyOption vo, bool *failures) const;
 708   void verify_rem_set() const;
 709 };
 710 
 711 // HeapRegionClosure is used for iterating over regions.
 712 // Terminates the iteration when the "do_heap_region" method returns "true".
 713 class HeapRegionClosure : public StackObj {
 714   friend class HeapRegionManager;
 715   friend class G1CollectionSet;
 716   friend class CollectionSetChooser;
 717 
 718   bool _is_complete;
 719   void set_incomplete() { _is_complete = false; }
 720 
 721  public:
 722   HeapRegionClosure(): _is_complete(true) {}
 723 
 724   // Typically called on each region until it returns true.
 725   virtual bool do_heap_region(HeapRegion* r) = 0;
 726 
 727   // True after iteration if the closure was applied to all heap regions
 728   // and returned "false" in all cases.
 729   bool is_complete() { return _is_complete; }
 730 };
 731 
 732 #endif // SHARE_VM_GC_G1_HEAPREGION_HPP
--- EOF ---