1 /*
   2  * Copyright (c) 2011, 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 #include "precompiled.hpp"
  25 #include "gc_interface/collectedHeap.hpp"
  26 #include "memory/allocation.hpp"
  27 #include "memory/binaryTreeDictionary.hpp"
  28 #include "memory/freeList.hpp"
  29 #include "memory/collectorPolicy.hpp"
  30 #include "memory/filemap.hpp"
  31 #include "memory/freeList.hpp"
  32 #include "memory/gcLocker.hpp"
  33 #include "memory/metachunk.hpp"
  34 #include "memory/metaspace.hpp"
  35 #include "memory/metaspaceGCThresholdUpdater.hpp"
  36 #include "memory/metaspaceShared.hpp"
  37 #include "memory/metaspaceTracer.hpp"
  38 #include "memory/resourceArea.hpp"
  39 #include "memory/universe.hpp"
  40 #include "runtime/atomic.inline.hpp"
  41 #include "runtime/globals.hpp"
  42 #include "runtime/init.hpp"
  43 #include "runtime/java.hpp"
  44 #include "runtime/mutex.hpp"
  45 #include "runtime/orderAccess.inline.hpp"
  46 #include "services/memTracker.hpp"
  47 #include "services/memoryService.hpp"
  48 #include "utilities/copy.hpp"
  49 #include "utilities/debug.hpp"
  50 
  51 PRAGMA_FORMAT_MUTE_WARNINGS_FOR_GCC
  52 
  53 typedef BinaryTreeDictionary<Metablock, FreeList<Metablock> > BlockTreeDictionary;
  54 typedef BinaryTreeDictionary<Metachunk, FreeList<Metachunk> > ChunkTreeDictionary;
  55 
  56 // Set this constant to enable slow integrity checking of the free chunk lists
  57 const bool metaspace_slow_verify = false;
  58 
  59 size_t const allocation_from_dictionary_limit = 4 * K;
  60 
  61 MetaWord* last_allocated = 0;
  62 
  63 size_t Metaspace::_compressed_class_space_size;
  64 const MetaspaceTracer* Metaspace::_tracer = NULL;
  65 
  66 // Used in declarations in SpaceManager and ChunkManager
  67 enum ChunkIndex {
  68   ZeroIndex = 0,
  69   SpecializedIndex = ZeroIndex,
  70   SmallIndex = SpecializedIndex + 1,
  71   MediumIndex = SmallIndex + 1,
  72   HumongousIndex = MediumIndex + 1,
  73   NumberOfFreeLists = 3,
  74   NumberOfInUseLists = 4
  75 };
  76 
  77 enum ChunkSizes {    // in words.
  78   ClassSpecializedChunk = 128,
  79   SpecializedChunk = 128,
  80   ClassSmallChunk = 256,
  81   SmallChunk = 512,
  82   ClassMediumChunk = 4 * K,
  83   MediumChunk = 8 * K
  84 };
  85 
  86 static ChunkIndex next_chunk_index(ChunkIndex i) {
  87   assert(i < NumberOfInUseLists, "Out of bound");
  88   return (ChunkIndex) (i+1);
  89 }
  90 
  91 volatile intptr_t MetaspaceGC::_capacity_until_GC = 0;
  92 uint MetaspaceGC::_shrink_factor = 0;
  93 bool MetaspaceGC::_should_concurrent_collect = false;
  94 
  95 typedef class FreeList<Metachunk> ChunkList;
  96 
  97 // Manages the global free lists of chunks.
  98 class ChunkManager : public CHeapObj<mtInternal> {
  99   friend class TestVirtualSpaceNodeTest;
 100 
 101   // Free list of chunks of different sizes.
 102   //   SpecializedChunk
 103   //   SmallChunk
 104   //   MediumChunk
 105   //   HumongousChunk
 106   ChunkList _free_chunks[NumberOfFreeLists];
 107 
 108   //   HumongousChunk
 109   ChunkTreeDictionary _humongous_dictionary;
 110 
 111   // ChunkManager in all lists of this type
 112   size_t _free_chunks_total;
 113   size_t _free_chunks_count;
 114 
 115   void dec_free_chunks_total(size_t v) {
 116     assert(_free_chunks_count > 0 &&
 117              _free_chunks_total > 0,
 118              "About to go negative");
 119     Atomic::add_ptr(-1, &_free_chunks_count);
 120     jlong minus_v = (jlong) - (jlong) v;
 121     Atomic::add_ptr(minus_v, &_free_chunks_total);
 122   }
 123 
 124   // Debug support
 125 
 126   size_t sum_free_chunks();
 127   size_t sum_free_chunks_count();
 128 
 129   void locked_verify_free_chunks_total();
 130   void slow_locked_verify_free_chunks_total() {
 131     if (metaspace_slow_verify) {
 132       locked_verify_free_chunks_total();
 133     }
 134   }
 135   void locked_verify_free_chunks_count();
 136   void slow_locked_verify_free_chunks_count() {
 137     if (metaspace_slow_verify) {
 138       locked_verify_free_chunks_count();
 139     }
 140   }
 141   void verify_free_chunks_count();
 142 
 143  public:
 144 
 145   ChunkManager(size_t specialized_size, size_t small_size, size_t medium_size)
 146       : _free_chunks_total(0), _free_chunks_count(0) {
 147     _free_chunks[SpecializedIndex].set_size(specialized_size);
 148     _free_chunks[SmallIndex].set_size(small_size);
 149     _free_chunks[MediumIndex].set_size(medium_size);
 150   }
 151 
 152   // add or delete (return) a chunk to the global freelist.
 153   Metachunk* chunk_freelist_allocate(size_t word_size);
 154 
 155   // Map a size to a list index assuming that there are lists
 156   // for special, small, medium, and humongous chunks.
 157   static ChunkIndex list_index(size_t size);
 158 
 159   // Remove the chunk from its freelist.  It is
 160   // expected to be on one of the _free_chunks[] lists.
 161   void remove_chunk(Metachunk* chunk);
 162 
 163   // Add the simple linked list of chunks to the freelist of chunks
 164   // of type index.
 165   void return_chunks(ChunkIndex index, Metachunk* chunks);
 166 
 167   // Total of the space in the free chunks list
 168   size_t free_chunks_total_words();
 169   size_t free_chunks_total_bytes();
 170 
 171   // Number of chunks in the free chunks list
 172   size_t free_chunks_count();
 173 
 174   void inc_free_chunks_total(size_t v, size_t count = 1) {
 175     Atomic::add_ptr(count, &_free_chunks_count);
 176     Atomic::add_ptr(v, &_free_chunks_total);
 177   }
 178   ChunkTreeDictionary* humongous_dictionary() {
 179     return &_humongous_dictionary;
 180   }
 181 
 182   ChunkList* free_chunks(ChunkIndex index);
 183 
 184   // Returns the list for the given chunk word size.
 185   ChunkList* find_free_chunks_list(size_t word_size);
 186 
 187   // Remove from a list by size.  Selects list based on size of chunk.
 188   Metachunk* free_chunks_get(size_t chunk_word_size);
 189 
 190 #define index_bounds_check(index)                                         \
 191   assert(index == SpecializedIndex ||                                     \
 192          index == SmallIndex ||                                           \
 193          index == MediumIndex ||                                          \
 194          index == HumongousIndex, err_msg("Bad index: %d", (int) index))
 195 
 196   size_t num_free_chunks(ChunkIndex index) const {
 197     index_bounds_check(index);
 198 
 199     if (index == HumongousIndex) {
 200       return _humongous_dictionary.total_free_blocks();
 201     }
 202 
 203     ssize_t count = _free_chunks[index].count();
 204     return count == -1 ? 0 : (size_t) count;
 205   }
 206 
 207   size_t size_free_chunks_in_bytes(ChunkIndex index) const {
 208     index_bounds_check(index);
 209 
 210     size_t word_size = 0;
 211     if (index == HumongousIndex) {
 212       word_size = _humongous_dictionary.total_size();
 213     } else {
 214       const size_t size_per_chunk_in_words = _free_chunks[index].size();
 215       word_size = size_per_chunk_in_words * num_free_chunks(index);
 216     }
 217 
 218     return word_size * BytesPerWord;
 219   }
 220 
 221   MetaspaceChunkFreeListSummary chunk_free_list_summary() const {
 222     return MetaspaceChunkFreeListSummary(num_free_chunks(SpecializedIndex),
 223                                          num_free_chunks(SmallIndex),
 224                                          num_free_chunks(MediumIndex),
 225                                          num_free_chunks(HumongousIndex),
 226                                          size_free_chunks_in_bytes(SpecializedIndex),
 227                                          size_free_chunks_in_bytes(SmallIndex),
 228                                          size_free_chunks_in_bytes(MediumIndex),
 229                                          size_free_chunks_in_bytes(HumongousIndex));
 230   }
 231 
 232   // Debug support
 233   void verify();
 234   void slow_verify() {
 235     if (metaspace_slow_verify) {
 236       verify();
 237     }
 238   }
 239   void locked_verify();
 240   void slow_locked_verify() {
 241     if (metaspace_slow_verify) {
 242       locked_verify();
 243     }
 244   }
 245   void verify_free_chunks_total();
 246 
 247   void locked_print_free_chunks(outputStream* st);
 248   void locked_print_sum_free_chunks(outputStream* st);
 249 
 250   void print_on(outputStream* st) const;
 251 };
 252 
 253 // Used to manage the free list of Metablocks (a block corresponds
 254 // to the allocation of a quantum of metadata).
 255 class BlockFreelist VALUE_OBJ_CLASS_SPEC {
 256   BlockTreeDictionary* _dictionary;
 257 
 258   // Only allocate and split from freelist if the size of the allocation
 259   // is at least 1/4th the size of the available block.
 260   const static int WasteMultiplier = 4;
 261 
 262   // Accessors
 263   BlockTreeDictionary* dictionary() const { return _dictionary; }
 264 
 265  public:
 266   BlockFreelist();
 267   ~BlockFreelist();
 268 
 269   // Get and return a block to the free list
 270   MetaWord* get_block(size_t word_size);
 271   void return_block(MetaWord* p, size_t word_size);
 272 
 273   size_t total_size() {
 274   if (dictionary() == NULL) {
 275     return 0;
 276   } else {
 277     return dictionary()->total_size();
 278   }
 279 }
 280 
 281   void print_on(outputStream* st) const;
 282 };
 283 
 284 // A VirtualSpaceList node.
 285 class VirtualSpaceNode : public CHeapObj<mtClass> {
 286   friend class VirtualSpaceList;
 287 
 288   // Link to next VirtualSpaceNode
 289   VirtualSpaceNode* _next;
 290 
 291   // total in the VirtualSpace
 292   MemRegion _reserved;
 293   ReservedSpace _rs;
 294   VirtualSpace _virtual_space;
 295   MetaWord* _top;
 296   // count of chunks contained in this VirtualSpace
 297   uintx _container_count;
 298 
 299   // Convenience functions to access the _virtual_space
 300   char* low()  const { return virtual_space()->low(); }
 301   char* high() const { return virtual_space()->high(); }
 302 
 303   // The first Metachunk will be allocated at the bottom of the
 304   // VirtualSpace
 305   Metachunk* first_chunk() { return (Metachunk*) bottom(); }
 306 
 307   // Committed but unused space in the virtual space
 308   size_t free_words_in_vs() const;
 309  public:
 310 
 311   VirtualSpaceNode(size_t byte_size);
 312   VirtualSpaceNode(ReservedSpace rs) : _top(NULL), _next(NULL), _rs(rs), _container_count(0) {}
 313   ~VirtualSpaceNode();
 314 
 315   // Convenience functions for logical bottom and end
 316   MetaWord* bottom() const { return (MetaWord*) _virtual_space.low(); }
 317   MetaWord* end() const { return (MetaWord*) _virtual_space.high(); }
 318 
 319   bool contains(const void* ptr) { return ptr >= low() && ptr < high(); }
 320 
 321   size_t reserved_words() const  { return _virtual_space.reserved_size() / BytesPerWord; }
 322   size_t committed_words() const { return _virtual_space.actual_committed_size() / BytesPerWord; }
 323 
 324   bool is_pre_committed() const { return _virtual_space.special(); }
 325 
 326   // address of next available space in _virtual_space;
 327   // Accessors
 328   VirtualSpaceNode* next() { return _next; }
 329   void set_next(VirtualSpaceNode* v) { _next = v; }
 330 
 331   void set_reserved(MemRegion const v) { _reserved = v; }
 332   void set_top(MetaWord* v) { _top = v; }
 333 
 334   // Accessors
 335   MemRegion* reserved() { return &_reserved; }
 336   VirtualSpace* virtual_space() const { return (VirtualSpace*) &_virtual_space; }
 337 
 338   // Returns true if "word_size" is available in the VirtualSpace
 339   bool is_available(size_t word_size) { return word_size <= pointer_delta(end(), _top, sizeof(MetaWord)); }
 340 
 341   MetaWord* top() const { return _top; }
 342   void inc_top(size_t word_size) { _top += word_size; }
 343 
 344   uintx container_count() { return _container_count; }
 345   void inc_container_count();
 346   void dec_container_count();
 347 #ifdef ASSERT
 348   uint container_count_slow();
 349   void verify_container_count();
 350 #endif
 351 
 352   // used and capacity in this single entry in the list
 353   size_t used_words_in_vs() const;
 354   size_t capacity_words_in_vs() const;
 355 
 356   bool initialize();
 357 
 358   // get space from the virtual space
 359   Metachunk* take_from_committed(size_t chunk_word_size);
 360 
 361   // Allocate a chunk from the virtual space and return it.
 362   Metachunk* get_chunk_vs(size_t chunk_word_size);
 363 
 364   // Expands/shrinks the committed space in a virtual space.  Delegates
 365   // to Virtualspace
 366   bool expand_by(size_t min_words, size_t preferred_words);
 367 
 368   // In preparation for deleting this node, remove all the chunks
 369   // in the node from any freelist.
 370   void purge(ChunkManager* chunk_manager);
 371 
 372   // If an allocation doesn't fit in the current node a new node is created.
 373   // Allocate chunks out of the remaining committed space in this node
 374   // to avoid wasting that memory.
 375   // This always adds up because all the chunk sizes are multiples of
 376   // the smallest chunk size.
 377   void retire(ChunkManager* chunk_manager);
 378 
 379 #ifdef ASSERT
 380   // Debug support
 381   void mangle();
 382 #endif
 383 
 384   void print_on(outputStream* st) const;
 385 };
 386 
 387 #define assert_is_ptr_aligned(ptr, alignment) \
 388   assert(is_ptr_aligned(ptr, alignment),      \
 389     err_msg(PTR_FORMAT " is not aligned to "  \
 390       SIZE_FORMAT, ptr, alignment))
 391 
 392 #define assert_is_size_aligned(size, alignment) \
 393   assert(is_size_aligned(size, alignment),      \
 394     err_msg(SIZE_FORMAT " is not aligned to "   \
 395        SIZE_FORMAT, size, alignment))
 396 
 397 
 398 // Decide if large pages should be committed when the memory is reserved.
 399 static bool should_commit_large_pages_when_reserving(size_t bytes) {
 400   if (UseLargePages && UseLargePagesInMetaspace && !os::can_commit_large_page_memory()) {
 401     size_t words = bytes / BytesPerWord;
 402     bool is_class = false; // We never reserve large pages for the class space.
 403     if (MetaspaceGC::can_expand(words, is_class) &&
 404         MetaspaceGC::allowed_expansion() >= words) {
 405       return true;
 406     }
 407   }
 408 
 409   return false;
 410 }
 411 
 412   // byte_size is the size of the associated virtualspace.
 413 VirtualSpaceNode::VirtualSpaceNode(size_t bytes) : _top(NULL), _next(NULL), _rs(), _container_count(0) {
 414   assert_is_size_aligned(bytes, Metaspace::reserve_alignment());
 415 
 416 #if INCLUDE_CDS
 417   // This allocates memory with mmap.  For DumpSharedspaces, try to reserve
 418   // configurable address, generally at the top of the Java heap so other
 419   // memory addresses don't conflict.
 420   if (DumpSharedSpaces) {
 421     bool large_pages = false; // No large pages when dumping the CDS archive.
 422     char* shared_base = (char*)align_ptr_up((char*)SharedBaseAddress, Metaspace::reserve_alignment());
 423 
 424     _rs = ReservedSpace(bytes, Metaspace::reserve_alignment(), large_pages, shared_base, 0);
 425     if (_rs.is_reserved()) {
 426       assert(shared_base == 0 || _rs.base() == shared_base, "should match");
 427     } else {
 428       // Get a mmap region anywhere if the SharedBaseAddress fails.
 429       _rs = ReservedSpace(bytes, Metaspace::reserve_alignment(), large_pages);
 430     }
 431     MetaspaceShared::set_shared_rs(&_rs);
 432   } else
 433 #endif
 434   {
 435     bool large_pages = should_commit_large_pages_when_reserving(bytes);
 436 
 437     _rs = ReservedSpace(bytes, Metaspace::reserve_alignment(), large_pages);
 438   }
 439 
 440   if (_rs.is_reserved()) {
 441     assert(_rs.base() != NULL, "Catch if we get a NULL address");
 442     assert(_rs.size() != 0, "Catch if we get a 0 size");
 443     assert_is_ptr_aligned(_rs.base(), Metaspace::reserve_alignment());
 444     assert_is_size_aligned(_rs.size(), Metaspace::reserve_alignment());
 445 
 446     MemTracker::record_virtual_memory_type((address)_rs.base(), mtClass);
 447   }
 448 }
 449 
 450 void VirtualSpaceNode::purge(ChunkManager* chunk_manager) {
 451   Metachunk* chunk = first_chunk();
 452   Metachunk* invalid_chunk = (Metachunk*) top();
 453   while (chunk < invalid_chunk ) {
 454     assert(chunk->is_tagged_free(), "Should be tagged free");
 455     MetaWord* next = ((MetaWord*)chunk) + chunk->word_size();
 456     chunk_manager->remove_chunk(chunk);
 457     assert(chunk->next() == NULL &&
 458            chunk->prev() == NULL,
 459            "Was not removed from its list");
 460     chunk = (Metachunk*) next;
 461   }
 462 }
 463 
 464 #ifdef ASSERT
 465 uint VirtualSpaceNode::container_count_slow() {
 466   uint count = 0;
 467   Metachunk* chunk = first_chunk();
 468   Metachunk* invalid_chunk = (Metachunk*) top();
 469   while (chunk < invalid_chunk ) {
 470     MetaWord* next = ((MetaWord*)chunk) + chunk->word_size();
 471     // Don't count the chunks on the free lists.  Those are
 472     // still part of the VirtualSpaceNode but not currently
 473     // counted.
 474     if (!chunk->is_tagged_free()) {
 475       count++;
 476     }
 477     chunk = (Metachunk*) next;
 478   }
 479   return count;
 480 }
 481 #endif
 482 
 483 // List of VirtualSpaces for metadata allocation.
 484 class VirtualSpaceList : public CHeapObj<mtClass> {
 485   friend class VirtualSpaceNode;
 486 
 487   enum VirtualSpaceSizes {
 488     VirtualSpaceSize = 256 * K
 489   };
 490 
 491   // Head of the list
 492   VirtualSpaceNode* _virtual_space_list;
 493   // virtual space currently being used for allocations
 494   VirtualSpaceNode* _current_virtual_space;
 495 
 496   // Is this VirtualSpaceList used for the compressed class space
 497   bool _is_class;
 498 
 499   // Sum of reserved and committed memory in the virtual spaces
 500   size_t _reserved_words;
 501   size_t _committed_words;
 502 
 503   // Number of virtual spaces
 504   size_t _virtual_space_count;
 505 
 506   ~VirtualSpaceList();
 507 
 508   VirtualSpaceNode* virtual_space_list() const { return _virtual_space_list; }
 509 
 510   void set_virtual_space_list(VirtualSpaceNode* v) {
 511     _virtual_space_list = v;
 512   }
 513   void set_current_virtual_space(VirtualSpaceNode* v) {
 514     _current_virtual_space = v;
 515   }
 516 
 517   void link_vs(VirtualSpaceNode* new_entry);
 518 
 519   // Get another virtual space and add it to the list.  This
 520   // is typically prompted by a failed attempt to allocate a chunk
 521   // and is typically followed by the allocation of a chunk.
 522   bool create_new_virtual_space(size_t vs_word_size);
 523 
 524   // Chunk up the unused committed space in the current
 525   // virtual space and add the chunks to the free list.
 526   void retire_current_virtual_space();
 527 
 528  public:
 529   VirtualSpaceList(size_t word_size);
 530   VirtualSpaceList(ReservedSpace rs);
 531 
 532   size_t free_bytes();
 533 
 534   Metachunk* get_new_chunk(size_t word_size,
 535                            size_t grow_chunks_by_words,
 536                            size_t medium_chunk_bunch);
 537 
 538   bool expand_node_by(VirtualSpaceNode* node,
 539                       size_t min_words,
 540                       size_t preferred_words);
 541 
 542   bool expand_by(size_t min_words,
 543                  size_t preferred_words);
 544 
 545   VirtualSpaceNode* current_virtual_space() {
 546     return _current_virtual_space;
 547   }
 548 
 549   bool is_class() const { return _is_class; }
 550 
 551   bool initialization_succeeded() { return _virtual_space_list != NULL; }
 552 
 553   size_t reserved_words()  { return _reserved_words; }
 554   size_t reserved_bytes()  { return reserved_words() * BytesPerWord; }
 555   size_t committed_words() { return _committed_words; }
 556   size_t committed_bytes() { return committed_words() * BytesPerWord; }
 557 
 558   void inc_reserved_words(size_t v);
 559   void dec_reserved_words(size_t v);
 560   void inc_committed_words(size_t v);
 561   void dec_committed_words(size_t v);
 562   void inc_virtual_space_count();
 563   void dec_virtual_space_count();
 564 
 565   bool contains(const void* ptr);
 566 
 567   // Unlink empty VirtualSpaceNodes and free it.
 568   void purge(ChunkManager* chunk_manager);
 569 
 570   void print_on(outputStream* st) const;
 571 
 572   class VirtualSpaceListIterator : public StackObj {
 573     VirtualSpaceNode* _virtual_spaces;
 574    public:
 575     VirtualSpaceListIterator(VirtualSpaceNode* virtual_spaces) :
 576       _virtual_spaces(virtual_spaces) {}
 577 
 578     bool repeat() {
 579       return _virtual_spaces != NULL;
 580     }
 581 
 582     VirtualSpaceNode* get_next() {
 583       VirtualSpaceNode* result = _virtual_spaces;
 584       if (_virtual_spaces != NULL) {
 585         _virtual_spaces = _virtual_spaces->next();
 586       }
 587       return result;
 588     }
 589   };
 590 };
 591 
 592 class Metadebug : AllStatic {
 593   // Debugging support for Metaspaces
 594   static int _allocation_fail_alot_count;
 595 
 596  public:
 597 
 598   static void init_allocation_fail_alot_count();
 599 #ifdef ASSERT
 600   static bool test_metadata_failure();
 601 #endif
 602 };
 603 
 604 int Metadebug::_allocation_fail_alot_count = 0;
 605 
 606 //  SpaceManager - used by Metaspace to handle allocations
 607 class SpaceManager : public CHeapObj<mtClass> {
 608   friend class Metaspace;
 609   friend class Metadebug;
 610 
 611  private:
 612 
 613   // protects allocations
 614   Mutex* const _lock;
 615 
 616   // Type of metadata allocated.
 617   Metaspace::MetadataType _mdtype;
 618 
 619   // List of chunks in use by this SpaceManager.  Allocations
 620   // are done from the current chunk.  The list is used for deallocating
 621   // chunks when the SpaceManager is freed.
 622   Metachunk* _chunks_in_use[NumberOfInUseLists];
 623   Metachunk* _current_chunk;
 624 
 625   // Number of small chunks to allocate to a manager
 626   // If class space manager, small chunks are unlimited
 627   static uint const _small_chunk_limit;
 628 
 629   // Sum of all space in allocated chunks
 630   size_t _allocated_blocks_words;
 631 
 632   // Sum of all allocated chunks
 633   size_t _allocated_chunks_words;
 634   size_t _allocated_chunks_count;
 635 
 636   // Free lists of blocks are per SpaceManager since they
 637   // are assumed to be in chunks in use by the SpaceManager
 638   // and all chunks in use by a SpaceManager are freed when
 639   // the class loader using the SpaceManager is collected.
 640   BlockFreelist _block_freelists;
 641 
 642   // protects virtualspace and chunk expansions
 643   static const char*  _expand_lock_name;
 644   static const int    _expand_lock_rank;
 645   static Mutex* const _expand_lock;
 646 
 647  private:
 648   // Accessors
 649   Metachunk* chunks_in_use(ChunkIndex index) const { return _chunks_in_use[index]; }
 650   void set_chunks_in_use(ChunkIndex index, Metachunk* v) {
 651     _chunks_in_use[index] = v;
 652   }
 653 
 654   BlockFreelist* block_freelists() const {
 655     return (BlockFreelist*) &_block_freelists;
 656   }
 657 
 658   Metaspace::MetadataType mdtype() { return _mdtype; }
 659 
 660   VirtualSpaceList* vs_list()   const { return Metaspace::get_space_list(_mdtype); }
 661   ChunkManager* chunk_manager() const { return Metaspace::get_chunk_manager(_mdtype); }
 662 
 663   Metachunk* current_chunk() const { return _current_chunk; }
 664   void set_current_chunk(Metachunk* v) {
 665     _current_chunk = v;
 666   }
 667 
 668   Metachunk* find_current_chunk(size_t word_size);
 669 
 670   // Add chunk to the list of chunks in use
 671   void add_chunk(Metachunk* v, bool make_current);
 672   void retire_current_chunk();
 673 
 674   Mutex* lock() const { return _lock; }
 675 
 676   const char* chunk_size_name(ChunkIndex index) const;
 677 
 678  protected:
 679   void initialize();
 680 
 681  public:
 682   SpaceManager(Metaspace::MetadataType mdtype,
 683                Mutex* lock);
 684   ~SpaceManager();
 685 
 686   enum ChunkMultiples {
 687     MediumChunkMultiple = 4
 688   };
 689 
 690   bool is_class() { return _mdtype == Metaspace::ClassType; }
 691 
 692   // Accessors
 693   size_t specialized_chunk_size() { return (size_t) is_class() ? ClassSpecializedChunk : SpecializedChunk; }
 694   size_t small_chunk_size()       { return (size_t) is_class() ? ClassSmallChunk : SmallChunk; }
 695   size_t medium_chunk_size()      { return (size_t) is_class() ? ClassMediumChunk : MediumChunk; }
 696   size_t medium_chunk_bunch()     { return medium_chunk_size() * MediumChunkMultiple; }
 697 
 698   size_t smallest_chunk_size()  { return specialized_chunk_size(); }
 699 
 700   size_t allocated_blocks_words() const { return _allocated_blocks_words; }
 701   size_t allocated_blocks_bytes() const { return _allocated_blocks_words * BytesPerWord; }
 702   size_t allocated_chunks_words() const { return _allocated_chunks_words; }
 703   size_t allocated_chunks_bytes() const { return _allocated_chunks_words * BytesPerWord; }
 704   size_t allocated_chunks_count() const { return _allocated_chunks_count; }
 705 
 706   bool is_humongous(size_t word_size) { return word_size > medium_chunk_size(); }
 707 
 708   static Mutex* expand_lock() { return _expand_lock; }
 709 
 710   // Increment the per Metaspace and global running sums for Metachunks
 711   // by the given size.  This is used when a Metachunk to added to
 712   // the in-use list.
 713   void inc_size_metrics(size_t words);
 714   // Increment the per Metaspace and global running sums Metablocks by the given
 715   // size.  This is used when a Metablock is allocated.
 716   void inc_used_metrics(size_t words);
 717   // Delete the portion of the running sums for this SpaceManager. That is,
 718   // the globals running sums for the Metachunks and Metablocks are
 719   // decremented for all the Metachunks in-use by this SpaceManager.
 720   void dec_total_from_size_metrics();
 721 
 722   // Set the sizes for the initial chunks.
 723   void get_initial_chunk_sizes(Metaspace::MetaspaceType type,
 724                                size_t* chunk_word_size,
 725                                size_t* class_chunk_word_size);
 726 
 727   size_t sum_capacity_in_chunks_in_use() const;
 728   size_t sum_used_in_chunks_in_use() const;
 729   size_t sum_free_in_chunks_in_use() const;
 730   size_t sum_waste_in_chunks_in_use() const;
 731   size_t sum_waste_in_chunks_in_use(ChunkIndex index ) const;
 732 
 733   size_t sum_count_in_chunks_in_use();
 734   size_t sum_count_in_chunks_in_use(ChunkIndex i);
 735 
 736   Metachunk* get_new_chunk(size_t word_size, size_t grow_chunks_by_words);
 737 
 738   // Block allocation and deallocation.
 739   // Allocates a block from the current chunk
 740   MetaWord* allocate(size_t word_size);
 741 
 742   // Helper for allocations
 743   MetaWord* allocate_work(size_t word_size);
 744 
 745   // Returns a block to the per manager freelist
 746   void deallocate(MetaWord* p, size_t word_size);
 747 
 748   // Based on the allocation size and a minimum chunk size,
 749   // returned chunk size (for expanding space for chunk allocation).
 750   size_t calc_chunk_size(size_t allocation_word_size);
 751 
 752   // Called when an allocation from the current chunk fails.
 753   // Gets a new chunk (may require getting a new virtual space),
 754   // and allocates from that chunk.
 755   MetaWord* grow_and_allocate(size_t word_size);
 756 
 757   // Notify memory usage to MemoryService.
 758   void track_metaspace_memory_usage();
 759 
 760   // debugging support.
 761 
 762   void dump(outputStream* const out) const;
 763   void print_on(outputStream* st) const;
 764   void locked_print_chunks_in_use_on(outputStream* st) const;
 765 
 766   void verify();
 767   void verify_chunk_size(Metachunk* chunk);
 768   NOT_PRODUCT(void mangle_freed_chunks();)
 769 #ifdef ASSERT
 770   void verify_allocated_blocks_words();
 771 #endif
 772 
 773   size_t get_raw_word_size(size_t word_size) {
 774     size_t byte_size = word_size * BytesPerWord;
 775 
 776     size_t raw_bytes_size = MAX2(byte_size, sizeof(Metablock));
 777     raw_bytes_size = align_size_up(raw_bytes_size, Metachunk::object_alignment());
 778 
 779     size_t raw_word_size = raw_bytes_size / BytesPerWord;
 780     assert(raw_word_size * BytesPerWord == raw_bytes_size, "Size problem");
 781 
 782     return raw_word_size;
 783   }
 784 };
 785 
 786 uint const SpaceManager::_small_chunk_limit = 4;
 787 
 788 const char* SpaceManager::_expand_lock_name =
 789   "SpaceManager chunk allocation lock";
 790 const int SpaceManager::_expand_lock_rank = Monitor::leaf - 1;
 791 Mutex* const SpaceManager::_expand_lock =
 792   new Mutex(SpaceManager::_expand_lock_rank,
 793             SpaceManager::_expand_lock_name,
 794             Mutex::_allow_vm_block_flag,
 795             Monitor::_safepoint_check_never);
 796 
 797 void VirtualSpaceNode::inc_container_count() {
 798   assert_lock_strong(SpaceManager::expand_lock());
 799   _container_count++;
 800   assert(_container_count == container_count_slow(),
 801          err_msg("Inconsistency in container_count _container_count " SIZE_FORMAT
 802                  " container_count_slow() " SIZE_FORMAT,
 803                  _container_count, container_count_slow()));
 804 }
 805 
 806 void VirtualSpaceNode::dec_container_count() {
 807   assert_lock_strong(SpaceManager::expand_lock());
 808   _container_count--;
 809 }
 810 
 811 #ifdef ASSERT
 812 void VirtualSpaceNode::verify_container_count() {
 813   assert(_container_count == container_count_slow(),
 814     err_msg("Inconsistency in container_count _container_count " SIZE_FORMAT
 815             " container_count_slow() " SIZE_FORMAT, _container_count, container_count_slow()));
 816 }
 817 #endif
 818 
 819 // BlockFreelist methods
 820 
 821 BlockFreelist::BlockFreelist() : _dictionary(NULL) {}
 822 
 823 BlockFreelist::~BlockFreelist() {
 824   if (_dictionary != NULL) {
 825     if (Verbose && TraceMetadataChunkAllocation) {
 826       _dictionary->print_free_lists(gclog_or_tty);
 827     }
 828     delete _dictionary;
 829   }
 830 }
 831 
 832 void BlockFreelist::return_block(MetaWord* p, size_t word_size) {
 833   Metablock* free_chunk = ::new (p) Metablock(word_size);
 834   if (dictionary() == NULL) {
 835    _dictionary = new BlockTreeDictionary();
 836   }
 837   dictionary()->return_chunk(free_chunk);
 838 }
 839 
 840 MetaWord* BlockFreelist::get_block(size_t word_size) {
 841   if (dictionary() == NULL) {
 842     return NULL;
 843   }
 844 
 845   if (word_size < TreeChunk<Metablock, FreeList<Metablock> >::min_size()) {
 846     // Dark matter.  Too small for dictionary.
 847     return NULL;
 848   }
 849 
 850   Metablock* free_block =
 851     dictionary()->get_chunk(word_size, FreeBlockDictionary<Metablock>::atLeast);
 852   if (free_block == NULL) {
 853     return NULL;
 854   }
 855 
 856   const size_t block_size = free_block->size();
 857   if (block_size > WasteMultiplier * word_size) {
 858     return_block((MetaWord*)free_block, block_size);
 859     return NULL;
 860   }
 861 
 862   MetaWord* new_block = (MetaWord*)free_block;
 863   assert(block_size >= word_size, "Incorrect size of block from freelist");
 864   const size_t unused = block_size - word_size;
 865   if (unused >= TreeChunk<Metablock, FreeList<Metablock> >::min_size()) {
 866     return_block(new_block + word_size, unused);
 867   }
 868 
 869   return new_block;
 870 }
 871 
 872 void BlockFreelist::print_on(outputStream* st) const {
 873   if (dictionary() == NULL) {
 874     return;
 875   }
 876   dictionary()->print_free_lists(st);
 877 }
 878 
 879 // VirtualSpaceNode methods
 880 
 881 VirtualSpaceNode::~VirtualSpaceNode() {
 882   _rs.release();
 883 #ifdef ASSERT
 884   size_t word_size = sizeof(*this) / BytesPerWord;
 885   Copy::fill_to_words((HeapWord*) this, word_size, 0xf1f1f1f1);
 886 #endif
 887 }
 888 
 889 size_t VirtualSpaceNode::used_words_in_vs() const {
 890   return pointer_delta(top(), bottom(), sizeof(MetaWord));
 891 }
 892 
 893 // Space committed in the VirtualSpace
 894 size_t VirtualSpaceNode::capacity_words_in_vs() const {
 895   return pointer_delta(end(), bottom(), sizeof(MetaWord));
 896 }
 897 
 898 size_t VirtualSpaceNode::free_words_in_vs() const {
 899   return pointer_delta(end(), top(), sizeof(MetaWord));
 900 }
 901 
 902 // Allocates the chunk from the virtual space only.
 903 // This interface is also used internally for debugging.  Not all
 904 // chunks removed here are necessarily used for allocation.
 905 Metachunk* VirtualSpaceNode::take_from_committed(size_t chunk_word_size) {
 906   // Bottom of the new chunk
 907   MetaWord* chunk_limit = top();
 908   assert(chunk_limit != NULL, "Not safe to call this method");
 909 
 910   // The virtual spaces are always expanded by the
 911   // commit granularity to enforce the following condition.
 912   // Without this the is_available check will not work correctly.
 913   assert(_virtual_space.committed_size() == _virtual_space.actual_committed_size(),
 914       "The committed memory doesn't match the expanded memory.");
 915 
 916   if (!is_available(chunk_word_size)) {
 917     if (TraceMetadataChunkAllocation) {
 918       gclog_or_tty->print("VirtualSpaceNode::take_from_committed() not available %d words ", chunk_word_size);
 919       // Dump some information about the virtual space that is nearly full
 920       print_on(gclog_or_tty);
 921     }
 922     return NULL;
 923   }
 924 
 925   // Take the space  (bump top on the current virtual space).
 926   inc_top(chunk_word_size);
 927 
 928   // Initialize the chunk
 929   Metachunk* result = ::new (chunk_limit) Metachunk(chunk_word_size, this);
 930   return result;
 931 }
 932 
 933 
 934 // Expand the virtual space (commit more of the reserved space)
 935 bool VirtualSpaceNode::expand_by(size_t min_words, size_t preferred_words) {
 936   size_t min_bytes = min_words * BytesPerWord;
 937   size_t preferred_bytes = preferred_words * BytesPerWord;
 938 
 939   size_t uncommitted = virtual_space()->reserved_size() - virtual_space()->actual_committed_size();
 940 
 941   if (uncommitted < min_bytes) {
 942     return false;
 943   }
 944 
 945   size_t commit = MIN2(preferred_bytes, uncommitted);
 946   bool result = virtual_space()->expand_by(commit, false);
 947 
 948   assert(result, "Failed to commit memory");
 949 
 950   return result;
 951 }
 952 
 953 Metachunk* VirtualSpaceNode::get_chunk_vs(size_t chunk_word_size) {
 954   assert_lock_strong(SpaceManager::expand_lock());
 955   Metachunk* result = take_from_committed(chunk_word_size);
 956   if (result != NULL) {
 957     inc_container_count();
 958   }
 959   return result;
 960 }
 961 
 962 bool VirtualSpaceNode::initialize() {
 963 
 964   if (!_rs.is_reserved()) {
 965     return false;
 966   }
 967 
 968   // These are necessary restriction to make sure that the virtual space always
 969   // grows in steps of Metaspace::commit_alignment(). If both base and size are
 970   // aligned only the middle alignment of the VirtualSpace is used.
 971   assert_is_ptr_aligned(_rs.base(), Metaspace::commit_alignment());
 972   assert_is_size_aligned(_rs.size(), Metaspace::commit_alignment());
 973 
 974   // ReservedSpaces marked as special will have the entire memory
 975   // pre-committed. Setting a committed size will make sure that
 976   // committed_size and actual_committed_size agrees.
 977   size_t pre_committed_size = _rs.special() ? _rs.size() : 0;
 978 
 979   bool result = virtual_space()->initialize_with_granularity(_rs, pre_committed_size,
 980                                             Metaspace::commit_alignment());
 981   if (result) {
 982     assert(virtual_space()->committed_size() == virtual_space()->actual_committed_size(),
 983         "Checking that the pre-committed memory was registered by the VirtualSpace");
 984 
 985     set_top((MetaWord*)virtual_space()->low());
 986     set_reserved(MemRegion((HeapWord*)_rs.base(),
 987                  (HeapWord*)(_rs.base() + _rs.size())));
 988 
 989     assert(reserved()->start() == (HeapWord*) _rs.base(),
 990       err_msg("Reserved start was not set properly " PTR_FORMAT
 991         " != " PTR_FORMAT, reserved()->start(), _rs.base()));
 992     assert(reserved()->word_size() == _rs.size() / BytesPerWord,
 993       err_msg("Reserved size was not set properly " SIZE_FORMAT
 994         " != " SIZE_FORMAT, reserved()->word_size(),
 995         _rs.size() / BytesPerWord));
 996   }
 997 
 998   return result;
 999 }
1000 
1001 void VirtualSpaceNode::print_on(outputStream* st) const {
1002   size_t used = used_words_in_vs();
1003   size_t capacity = capacity_words_in_vs();
1004   VirtualSpace* vs = virtual_space();
1005   st->print_cr("   space @ " PTR_FORMAT " " SIZE_FORMAT "K, %3d%% used "
1006            "[" PTR_FORMAT ", " PTR_FORMAT ", "
1007            PTR_FORMAT ", " PTR_FORMAT ")",
1008            vs, capacity / K,
1009            capacity == 0 ? 0 : used * 100 / capacity,
1010            bottom(), top(), end(),
1011            vs->high_boundary());
1012 }
1013 
1014 #ifdef ASSERT
1015 void VirtualSpaceNode::mangle() {
1016   size_t word_size = capacity_words_in_vs();
1017   Copy::fill_to_words((HeapWord*) low(), word_size, 0xf1f1f1f1);
1018 }
1019 #endif // ASSERT
1020 
1021 // VirtualSpaceList methods
1022 // Space allocated from the VirtualSpace
1023 
1024 VirtualSpaceList::~VirtualSpaceList() {
1025   VirtualSpaceListIterator iter(virtual_space_list());
1026   while (iter.repeat()) {
1027     VirtualSpaceNode* vsl = iter.get_next();
1028     delete vsl;
1029   }
1030 }
1031 
1032 void VirtualSpaceList::inc_reserved_words(size_t v) {
1033   assert_lock_strong(SpaceManager::expand_lock());
1034   _reserved_words = _reserved_words + v;
1035 }
1036 void VirtualSpaceList::dec_reserved_words(size_t v) {
1037   assert_lock_strong(SpaceManager::expand_lock());
1038   _reserved_words = _reserved_words - v;
1039 }
1040 
1041 #define assert_committed_below_limit()                             \
1042   assert(MetaspaceAux::committed_bytes() <= MaxMetaspaceSize,      \
1043       err_msg("Too much committed memory. Committed: " SIZE_FORMAT \
1044               " limit (MaxMetaspaceSize): " SIZE_FORMAT,           \
1045           MetaspaceAux::committed_bytes(), MaxMetaspaceSize));
1046 
1047 void VirtualSpaceList::inc_committed_words(size_t v) {
1048   assert_lock_strong(SpaceManager::expand_lock());
1049   _committed_words = _committed_words + v;
1050 
1051   assert_committed_below_limit();
1052 }
1053 void VirtualSpaceList::dec_committed_words(size_t v) {
1054   assert_lock_strong(SpaceManager::expand_lock());
1055   _committed_words = _committed_words - v;
1056 
1057   assert_committed_below_limit();
1058 }
1059 
1060 void VirtualSpaceList::inc_virtual_space_count() {
1061   assert_lock_strong(SpaceManager::expand_lock());
1062   _virtual_space_count++;
1063 }
1064 void VirtualSpaceList::dec_virtual_space_count() {
1065   assert_lock_strong(SpaceManager::expand_lock());
1066   _virtual_space_count--;
1067 }
1068 
1069 void ChunkManager::remove_chunk(Metachunk* chunk) {
1070   size_t word_size = chunk->word_size();
1071   ChunkIndex index = list_index(word_size);
1072   if (index != HumongousIndex) {
1073     free_chunks(index)->remove_chunk(chunk);
1074   } else {
1075     humongous_dictionary()->remove_chunk(chunk);
1076   }
1077 
1078   // Chunk is being removed from the chunks free list.
1079   dec_free_chunks_total(chunk->word_size());
1080 }
1081 
1082 // Walk the list of VirtualSpaceNodes and delete
1083 // nodes with a 0 container_count.  Remove Metachunks in
1084 // the node from their respective freelists.
1085 void VirtualSpaceList::purge(ChunkManager* chunk_manager) {
1086   assert(SafepointSynchronize::is_at_safepoint(), "must be called at safepoint for contains to work");
1087   assert_lock_strong(SpaceManager::expand_lock());
1088   // Don't use a VirtualSpaceListIterator because this
1089   // list is being changed and a straightforward use of an iterator is not safe.
1090   VirtualSpaceNode* purged_vsl = NULL;
1091   VirtualSpaceNode* prev_vsl = virtual_space_list();
1092   VirtualSpaceNode* next_vsl = prev_vsl;
1093   while (next_vsl != NULL) {
1094     VirtualSpaceNode* vsl = next_vsl;
1095     next_vsl = vsl->next();
1096     // Don't free the current virtual space since it will likely
1097     // be needed soon.
1098     if (vsl->container_count() == 0 && vsl != current_virtual_space()) {
1099       // Unlink it from the list
1100       if (prev_vsl == vsl) {
1101         // This is the case of the current node being the first node.
1102         assert(vsl == virtual_space_list(), "Expected to be the first node");
1103         set_virtual_space_list(vsl->next());
1104       } else {
1105         prev_vsl->set_next(vsl->next());
1106       }
1107 
1108       vsl->purge(chunk_manager);
1109       dec_reserved_words(vsl->reserved_words());
1110       dec_committed_words(vsl->committed_words());
1111       dec_virtual_space_count();
1112       purged_vsl = vsl;
1113       delete vsl;
1114     } else {
1115       prev_vsl = vsl;
1116     }
1117   }
1118 #ifdef ASSERT
1119   if (purged_vsl != NULL) {
1120     // List should be stable enough to use an iterator here.
1121     VirtualSpaceListIterator iter(virtual_space_list());
1122     while (iter.repeat()) {
1123       VirtualSpaceNode* vsl = iter.get_next();
1124       assert(vsl != purged_vsl, "Purge of vsl failed");
1125     }
1126   }
1127 #endif
1128 }
1129 
1130 
1131 // This function looks at the mmap regions in the metaspace without locking.
1132 // The chunks are added with store ordering and not deleted except for at
1133 // unloading time during a safepoint.
1134 bool VirtualSpaceList::contains(const void* ptr) {
1135   // List should be stable enough to use an iterator here because removing virtual
1136   // space nodes is only allowed at a safepoint.
1137   VirtualSpaceListIterator iter(virtual_space_list());
1138   while (iter.repeat()) {
1139     VirtualSpaceNode* vsn = iter.get_next();
1140     if (vsn->contains(ptr)) {
1141       return true;
1142     }
1143   }
1144   return false;
1145 }
1146 
1147 void VirtualSpaceList::retire_current_virtual_space() {
1148   assert_lock_strong(SpaceManager::expand_lock());
1149 
1150   VirtualSpaceNode* vsn = current_virtual_space();
1151 
1152   ChunkManager* cm = is_class() ? Metaspace::chunk_manager_class() :
1153                                   Metaspace::chunk_manager_metadata();
1154 
1155   vsn->retire(cm);
1156 }
1157 
1158 void VirtualSpaceNode::retire(ChunkManager* chunk_manager) {
1159   for (int i = (int)MediumIndex; i >= (int)ZeroIndex; --i) {
1160     ChunkIndex index = (ChunkIndex)i;
1161     size_t chunk_size = chunk_manager->free_chunks(index)->size();
1162 
1163     while (free_words_in_vs() >= chunk_size) {
1164       DEBUG_ONLY(verify_container_count();)
1165       Metachunk* chunk = get_chunk_vs(chunk_size);
1166       assert(chunk != NULL, "allocation should have been successful");
1167 
1168       chunk_manager->return_chunks(index, chunk);
1169       chunk_manager->inc_free_chunks_total(chunk_size);
1170       DEBUG_ONLY(verify_container_count();)
1171     }
1172   }
1173   assert(free_words_in_vs() == 0, "should be empty now");
1174 }
1175 
1176 VirtualSpaceList::VirtualSpaceList(size_t word_size) :
1177                                    _is_class(false),
1178                                    _virtual_space_list(NULL),
1179                                    _current_virtual_space(NULL),
1180                                    _reserved_words(0),
1181                                    _committed_words(0),
1182                                    _virtual_space_count(0) {
1183   MutexLockerEx cl(SpaceManager::expand_lock(),
1184                    Mutex::_no_safepoint_check_flag);
1185   create_new_virtual_space(word_size);
1186 }
1187 
1188 VirtualSpaceList::VirtualSpaceList(ReservedSpace rs) :
1189                                    _is_class(true),
1190                                    _virtual_space_list(NULL),
1191                                    _current_virtual_space(NULL),
1192                                    _reserved_words(0),
1193                                    _committed_words(0),
1194                                    _virtual_space_count(0) {
1195   MutexLockerEx cl(SpaceManager::expand_lock(),
1196                    Mutex::_no_safepoint_check_flag);
1197   VirtualSpaceNode* class_entry = new VirtualSpaceNode(rs);
1198   bool succeeded = class_entry->initialize();
1199   if (succeeded) {
1200     link_vs(class_entry);
1201   }
1202 }
1203 
1204 size_t VirtualSpaceList::free_bytes() {
1205   return virtual_space_list()->free_words_in_vs() * BytesPerWord;
1206 }
1207 
1208 // Allocate another meta virtual space and add it to the list.
1209 bool VirtualSpaceList::create_new_virtual_space(size_t vs_word_size) {
1210   assert_lock_strong(SpaceManager::expand_lock());
1211 
1212   if (is_class()) {
1213     assert(false, "We currently don't support more than one VirtualSpace for"
1214                   " the compressed class space. The initialization of the"
1215                   " CCS uses another code path and should not hit this path.");
1216     return false;
1217   }
1218 
1219   if (vs_word_size == 0) {
1220     assert(false, "vs_word_size should always be at least _reserve_alignment large.");
1221     return false;
1222   }
1223 
1224   // Reserve the space
1225   size_t vs_byte_size = vs_word_size * BytesPerWord;
1226   assert_is_size_aligned(vs_byte_size, Metaspace::reserve_alignment());
1227 
1228   // Allocate the meta virtual space and initialize it.
1229   VirtualSpaceNode* new_entry = new VirtualSpaceNode(vs_byte_size);
1230   if (!new_entry->initialize()) {
1231     delete new_entry;
1232     return false;
1233   } else {
1234     assert(new_entry->reserved_words() == vs_word_size,
1235         "Reserved memory size differs from requested memory size");
1236     // ensure lock-free iteration sees fully initialized node
1237     OrderAccess::storestore();
1238     link_vs(new_entry);
1239     return true;
1240   }
1241 }
1242 
1243 void VirtualSpaceList::link_vs(VirtualSpaceNode* new_entry) {
1244   if (virtual_space_list() == NULL) {
1245       set_virtual_space_list(new_entry);
1246   } else {
1247     current_virtual_space()->set_next(new_entry);
1248   }
1249   set_current_virtual_space(new_entry);
1250   inc_reserved_words(new_entry->reserved_words());
1251   inc_committed_words(new_entry->committed_words());
1252   inc_virtual_space_count();
1253 #ifdef ASSERT
1254   new_entry->mangle();
1255 #endif
1256   if (TraceMetavirtualspaceAllocation && Verbose) {
1257     VirtualSpaceNode* vsl = current_virtual_space();
1258     vsl->print_on(gclog_or_tty);
1259   }
1260 }
1261 
1262 bool VirtualSpaceList::expand_node_by(VirtualSpaceNode* node,
1263                                       size_t min_words,
1264                                       size_t preferred_words) {
1265   size_t before = node->committed_words();
1266 
1267   bool result = node->expand_by(min_words, preferred_words);
1268 
1269   size_t after = node->committed_words();
1270 
1271   // after and before can be the same if the memory was pre-committed.
1272   assert(after >= before, "Inconsistency");
1273   inc_committed_words(after - before);
1274 
1275   return result;
1276 }
1277 
1278 bool VirtualSpaceList::expand_by(size_t min_words, size_t preferred_words) {
1279   assert_is_size_aligned(min_words,       Metaspace::commit_alignment_words());
1280   assert_is_size_aligned(preferred_words, Metaspace::commit_alignment_words());
1281   assert(min_words <= preferred_words, "Invalid arguments");
1282 
1283   if (!MetaspaceGC::can_expand(min_words, this->is_class())) {
1284     return  false;
1285   }
1286 
1287   size_t allowed_expansion_words = MetaspaceGC::allowed_expansion();
1288   if (allowed_expansion_words < min_words) {
1289     return false;
1290   }
1291 
1292   size_t max_expansion_words = MIN2(preferred_words, allowed_expansion_words);
1293 
1294   // Commit more memory from the the current virtual space.
1295   bool vs_expanded = expand_node_by(current_virtual_space(),
1296                                     min_words,
1297                                     max_expansion_words);
1298   if (vs_expanded) {
1299     return true;
1300   }
1301   retire_current_virtual_space();
1302 
1303   // Get another virtual space.
1304   size_t grow_vs_words = MAX2((size_t)VirtualSpaceSize, preferred_words);
1305   grow_vs_words = align_size_up(grow_vs_words, Metaspace::reserve_alignment_words());
1306 
1307   if (create_new_virtual_space(grow_vs_words)) {
1308     if (current_virtual_space()->is_pre_committed()) {
1309       // The memory was pre-committed, so we are done here.
1310       assert(min_words <= current_virtual_space()->committed_words(),
1311           "The new VirtualSpace was pre-committed, so it"
1312           "should be large enough to fit the alloc request.");
1313       return true;
1314     }
1315 
1316     return expand_node_by(current_virtual_space(),
1317                           min_words,
1318                           max_expansion_words);
1319   }
1320 
1321   return false;
1322 }
1323 
1324 Metachunk* VirtualSpaceList::get_new_chunk(size_t word_size,
1325                                            size_t grow_chunks_by_words,
1326                                            size_t medium_chunk_bunch) {
1327 
1328   // Allocate a chunk out of the current virtual space.
1329   Metachunk* next = current_virtual_space()->get_chunk_vs(grow_chunks_by_words);
1330 
1331   if (next != NULL) {
1332     return next;
1333   }
1334 
1335   // The expand amount is currently only determined by the requested sizes
1336   // and not how much committed memory is left in the current virtual space.
1337 
1338   size_t min_word_size       = align_size_up(grow_chunks_by_words, Metaspace::commit_alignment_words());
1339   size_t preferred_word_size = align_size_up(medium_chunk_bunch,   Metaspace::commit_alignment_words());
1340   if (min_word_size >= preferred_word_size) {
1341     // Can happen when humongous chunks are allocated.
1342     preferred_word_size = min_word_size;
1343   }
1344 
1345   bool expanded = expand_by(min_word_size, preferred_word_size);
1346   if (expanded) {
1347     next = current_virtual_space()->get_chunk_vs(grow_chunks_by_words);
1348     assert(next != NULL, "The allocation was expected to succeed after the expansion");
1349   }
1350 
1351    return next;
1352 }
1353 
1354 void VirtualSpaceList::print_on(outputStream* st) const {
1355   if (TraceMetadataChunkAllocation && Verbose) {
1356     VirtualSpaceListIterator iter(virtual_space_list());
1357     while (iter.repeat()) {
1358       VirtualSpaceNode* node = iter.get_next();
1359       node->print_on(st);
1360     }
1361   }
1362 }
1363 
1364 // MetaspaceGC methods
1365 
1366 // VM_CollectForMetadataAllocation is the vm operation used to GC.
1367 // Within the VM operation after the GC the attempt to allocate the metadata
1368 // should succeed.  If the GC did not free enough space for the metaspace
1369 // allocation, the HWM is increased so that another virtualspace will be
1370 // allocated for the metadata.  With perm gen the increase in the perm
1371 // gen had bounds, MinMetaspaceExpansion and MaxMetaspaceExpansion.  The
1372 // metaspace policy uses those as the small and large steps for the HWM.
1373 //
1374 // After the GC the compute_new_size() for MetaspaceGC is called to
1375 // resize the capacity of the metaspaces.  The current implementation
1376 // is based on the flags MinMetaspaceFreeRatio and MaxMetaspaceFreeRatio used
1377 // to resize the Java heap by some GC's.  New flags can be implemented
1378 // if really needed.  MinMetaspaceFreeRatio is used to calculate how much
1379 // free space is desirable in the metaspace capacity to decide how much
1380 // to increase the HWM.  MaxMetaspaceFreeRatio is used to decide how much
1381 // free space is desirable in the metaspace capacity before decreasing
1382 // the HWM.
1383 
1384 // Calculate the amount to increase the high water mark (HWM).
1385 // Increase by a minimum amount (MinMetaspaceExpansion) so that
1386 // another expansion is not requested too soon.  If that is not
1387 // enough to satisfy the allocation, increase by MaxMetaspaceExpansion.
1388 // If that is still not enough, expand by the size of the allocation
1389 // plus some.
1390 size_t MetaspaceGC::delta_capacity_until_GC(size_t bytes) {
1391   size_t min_delta = MinMetaspaceExpansion;
1392   size_t max_delta = MaxMetaspaceExpansion;
1393   size_t delta = align_size_up(bytes, Metaspace::commit_alignment());
1394 
1395   if (delta <= min_delta) {
1396     delta = min_delta;
1397   } else if (delta <= max_delta) {
1398     // Don't want to hit the high water mark on the next
1399     // allocation so make the delta greater than just enough
1400     // for this allocation.
1401     delta = max_delta;
1402   } else {
1403     // This allocation is large but the next ones are probably not
1404     // so increase by the minimum.
1405     delta = delta + min_delta;
1406   }
1407 
1408   assert_is_size_aligned(delta, Metaspace::commit_alignment());
1409 
1410   return delta;
1411 }
1412 
1413 size_t MetaspaceGC::capacity_until_GC() {
1414   size_t value = (size_t)OrderAccess::load_ptr_acquire(&_capacity_until_GC);
1415   assert(value >= MetaspaceSize, "Not initialied properly?");
1416   return value;
1417 }
1418 
1419 bool MetaspaceGC::inc_capacity_until_GC(size_t v, size_t* new_cap_until_GC, size_t* old_cap_until_GC) {
1420   assert_is_size_aligned(v, Metaspace::commit_alignment());
1421 
1422   size_t capacity_until_GC = (size_t) _capacity_until_GC;
1423   size_t new_value = capacity_until_GC + v;
1424 
1425   if (new_value < capacity_until_GC) {
1426     // The addition wrapped around, set new_value to aligned max value.
1427     new_value = align_size_down(max_uintx, Metaspace::commit_alignment());
1428   }
1429 
1430   intptr_t expected = (intptr_t) capacity_until_GC;
1431   intptr_t actual = Atomic::cmpxchg_ptr((intptr_t) new_value, &_capacity_until_GC, expected);
1432 
1433   if (expected != actual) {
1434     return false;
1435   }
1436 
1437   if (new_cap_until_GC != NULL) {
1438     *new_cap_until_GC = new_value;
1439   }
1440   if (old_cap_until_GC != NULL) {
1441     *old_cap_until_GC = capacity_until_GC;
1442   }
1443   return true;
1444 }
1445 
1446 size_t MetaspaceGC::dec_capacity_until_GC(size_t v) {
1447   assert_is_size_aligned(v, Metaspace::commit_alignment());
1448 
1449   return (size_t)Atomic::add_ptr(-(intptr_t)v, &_capacity_until_GC);
1450 }
1451 
1452 void MetaspaceGC::initialize() {
1453   // Set the high-water mark to MaxMetapaceSize during VM initializaton since
1454   // we can't do a GC during initialization.
1455   _capacity_until_GC = MaxMetaspaceSize;
1456 }
1457 
1458 void MetaspaceGC::post_initialize() {
1459   // Reset the high-water mark once the VM initialization is done.
1460   _capacity_until_GC = MAX2(MetaspaceAux::committed_bytes(), MetaspaceSize);
1461 }
1462 
1463 bool MetaspaceGC::can_expand(size_t word_size, bool is_class) {
1464   // Check if the compressed class space is full.
1465   if (is_class && Metaspace::using_class_space()) {
1466     size_t class_committed = MetaspaceAux::committed_bytes(Metaspace::ClassType);
1467     if (class_committed + word_size * BytesPerWord > CompressedClassSpaceSize) {
1468       return false;
1469     }
1470   }
1471 
1472   // Check if the user has imposed a limit on the metaspace memory.
1473   size_t committed_bytes = MetaspaceAux::committed_bytes();
1474   if (committed_bytes + word_size * BytesPerWord > MaxMetaspaceSize) {
1475     return false;
1476   }
1477 
1478   return true;
1479 }
1480 
1481 size_t MetaspaceGC::allowed_expansion() {
1482   size_t committed_bytes = MetaspaceAux::committed_bytes();
1483   size_t capacity_until_gc = capacity_until_GC();
1484 
1485   assert(capacity_until_gc >= committed_bytes,
1486         err_msg("capacity_until_gc: " SIZE_FORMAT " < committed_bytes: " SIZE_FORMAT,
1487                 capacity_until_gc, committed_bytes));
1488 
1489   size_t left_until_max  = MaxMetaspaceSize - committed_bytes;
1490   size_t left_until_GC = capacity_until_gc - committed_bytes;
1491   size_t left_to_commit = MIN2(left_until_GC, left_until_max);
1492 
1493   return left_to_commit / BytesPerWord;
1494 }
1495 
1496 void MetaspaceGC::compute_new_size() {
1497   assert(_shrink_factor <= 100, "invalid shrink factor");
1498   uint current_shrink_factor = _shrink_factor;
1499   _shrink_factor = 0;
1500 
1501   // Using committed_bytes() for used_after_gc is an overestimation, since the
1502   // chunk free lists are included in committed_bytes() and the memory in an
1503   // un-fragmented chunk free list is available for future allocations.
1504   // However, if the chunk free lists becomes fragmented, then the memory may
1505   // not be available for future allocations and the memory is therefore "in use".
1506   // Including the chunk free lists in the definition of "in use" is therefore
1507   // necessary. Not including the chunk free lists can cause capacity_until_GC to
1508   // shrink below committed_bytes() and this has caused serious bugs in the past.
1509   const size_t used_after_gc = MetaspaceAux::committed_bytes();
1510   const size_t capacity_until_GC = MetaspaceGC::capacity_until_GC();
1511 
1512   const double minimum_free_percentage = MinMetaspaceFreeRatio / 100.0;
1513   const double maximum_used_percentage = 1.0 - minimum_free_percentage;
1514 
1515   const double min_tmp = used_after_gc / maximum_used_percentage;
1516   size_t minimum_desired_capacity =
1517     (size_t)MIN2(min_tmp, double(max_uintx));
1518   // Don't shrink less than the initial generation size
1519   minimum_desired_capacity = MAX2(minimum_desired_capacity,
1520                                   MetaspaceSize);
1521 
1522   if (PrintGCDetails && Verbose) {
1523     gclog_or_tty->print_cr("\nMetaspaceGC::compute_new_size: ");
1524     gclog_or_tty->print_cr("  "
1525                   "  minimum_free_percentage: %6.2f"
1526                   "  maximum_used_percentage: %6.2f",
1527                   minimum_free_percentage,
1528                   maximum_used_percentage);
1529     gclog_or_tty->print_cr("  "
1530                   "   used_after_gc       : %6.1fKB",
1531                   used_after_gc / (double) K);
1532   }
1533 
1534 
1535   size_t shrink_bytes = 0;
1536   if (capacity_until_GC < minimum_desired_capacity) {
1537     // If we have less capacity below the metaspace HWM, then
1538     // increment the HWM.
1539     size_t expand_bytes = minimum_desired_capacity - capacity_until_GC;
1540     expand_bytes = align_size_up(expand_bytes, Metaspace::commit_alignment());
1541     // Don't expand unless it's significant
1542     if (expand_bytes >= MinMetaspaceExpansion) {
1543       size_t new_capacity_until_GC = 0;
1544       bool succeeded = MetaspaceGC::inc_capacity_until_GC(expand_bytes, &new_capacity_until_GC);
1545       assert(succeeded, "Should always succesfully increment HWM when at safepoint");
1546 
1547       Metaspace::tracer()->report_gc_threshold(capacity_until_GC,
1548                                                new_capacity_until_GC,
1549                                                MetaspaceGCThresholdUpdater::ComputeNewSize);
1550       if (PrintGCDetails && Verbose) {
1551         gclog_or_tty->print_cr("    expanding:"
1552                       "  minimum_desired_capacity: %6.1fKB"
1553                       "  expand_bytes: %6.1fKB"
1554                       "  MinMetaspaceExpansion: %6.1fKB"
1555                       "  new metaspace HWM:  %6.1fKB",
1556                       minimum_desired_capacity / (double) K,
1557                       expand_bytes / (double) K,
1558                       MinMetaspaceExpansion / (double) K,
1559                       new_capacity_until_GC / (double) K);
1560       }
1561     }
1562     return;
1563   }
1564 
1565   // No expansion, now see if we want to shrink
1566   // We would never want to shrink more than this
1567   assert(capacity_until_GC >= minimum_desired_capacity,
1568          err_msg(SIZE_FORMAT " >= " SIZE_FORMAT,
1569                  capacity_until_GC, minimum_desired_capacity));
1570   size_t max_shrink_bytes = capacity_until_GC - minimum_desired_capacity;
1571 
1572   // Should shrinking be considered?
1573   if (MaxMetaspaceFreeRatio < 100) {
1574     const double maximum_free_percentage = MaxMetaspaceFreeRatio / 100.0;
1575     const double minimum_used_percentage = 1.0 - maximum_free_percentage;
1576     const double max_tmp = used_after_gc / minimum_used_percentage;
1577     size_t maximum_desired_capacity = (size_t)MIN2(max_tmp, double(max_uintx));
1578     maximum_desired_capacity = MAX2(maximum_desired_capacity,
1579                                     MetaspaceSize);
1580     if (PrintGCDetails && Verbose) {
1581       gclog_or_tty->print_cr("  "
1582                              "  maximum_free_percentage: %6.2f"
1583                              "  minimum_used_percentage: %6.2f",
1584                              maximum_free_percentage,
1585                              minimum_used_percentage);
1586       gclog_or_tty->print_cr("  "
1587                              "  minimum_desired_capacity: %6.1fKB"
1588                              "  maximum_desired_capacity: %6.1fKB",
1589                              minimum_desired_capacity / (double) K,
1590                              maximum_desired_capacity / (double) K);
1591     }
1592 
1593     assert(minimum_desired_capacity <= maximum_desired_capacity,
1594            "sanity check");
1595 
1596     if (capacity_until_GC > maximum_desired_capacity) {
1597       // Capacity too large, compute shrinking size
1598       shrink_bytes = capacity_until_GC - maximum_desired_capacity;
1599       // We don't want shrink all the way back to initSize if people call
1600       // System.gc(), because some programs do that between "phases" and then
1601       // we'd just have to grow the heap up again for the next phase.  So we
1602       // damp the shrinking: 0% on the first call, 10% on the second call, 40%
1603       // on the third call, and 100% by the fourth call.  But if we recompute
1604       // size without shrinking, it goes back to 0%.
1605       shrink_bytes = shrink_bytes / 100 * current_shrink_factor;
1606 
1607       shrink_bytes = align_size_down(shrink_bytes, Metaspace::commit_alignment());
1608 
1609       assert(shrink_bytes <= max_shrink_bytes,
1610         err_msg("invalid shrink size " SIZE_FORMAT " not <= " SIZE_FORMAT,
1611           shrink_bytes, max_shrink_bytes));
1612       if (current_shrink_factor == 0) {
1613         _shrink_factor = 10;
1614       } else {
1615         _shrink_factor = MIN2(current_shrink_factor * 4, (uint) 100);
1616       }
1617       if (PrintGCDetails && Verbose) {
1618         gclog_or_tty->print_cr("  "
1619                       "  shrinking:"
1620                       "  initSize: %.1fK"
1621                       "  maximum_desired_capacity: %.1fK",
1622                       MetaspaceSize / (double) K,
1623                       maximum_desired_capacity / (double) K);
1624         gclog_or_tty->print_cr("  "
1625                       "  shrink_bytes: %.1fK"
1626                       "  current_shrink_factor: %d"
1627                       "  new shrink factor: %d"
1628                       "  MinMetaspaceExpansion: %.1fK",
1629                       shrink_bytes / (double) K,
1630                       current_shrink_factor,
1631                       _shrink_factor,
1632                       MinMetaspaceExpansion / (double) K);
1633       }
1634     }
1635   }
1636 
1637   // Don't shrink unless it's significant
1638   if (shrink_bytes >= MinMetaspaceExpansion &&
1639       ((capacity_until_GC - shrink_bytes) >= MetaspaceSize)) {
1640     size_t new_capacity_until_GC = MetaspaceGC::dec_capacity_until_GC(shrink_bytes);
1641     Metaspace::tracer()->report_gc_threshold(capacity_until_GC,
1642                                              new_capacity_until_GC,
1643                                              MetaspaceGCThresholdUpdater::ComputeNewSize);
1644   }
1645 }
1646 
1647 // Metadebug methods
1648 
1649 void Metadebug::init_allocation_fail_alot_count() {
1650   if (MetadataAllocationFailALot) {
1651     _allocation_fail_alot_count =
1652       1+(long)((double)MetadataAllocationFailALotInterval*os::random()/(max_jint+1.0));
1653   }
1654 }
1655 
1656 #ifdef ASSERT
1657 bool Metadebug::test_metadata_failure() {
1658   if (MetadataAllocationFailALot &&
1659       Threads::is_vm_complete()) {
1660     if (_allocation_fail_alot_count > 0) {
1661       _allocation_fail_alot_count--;
1662     } else {
1663       if (TraceMetadataChunkAllocation && Verbose) {
1664         gclog_or_tty->print_cr("Metadata allocation failing for "
1665                                "MetadataAllocationFailALot");
1666       }
1667       init_allocation_fail_alot_count();
1668       return true;
1669     }
1670   }
1671   return false;
1672 }
1673 #endif
1674 
1675 // ChunkManager methods
1676 
1677 size_t ChunkManager::free_chunks_total_words() {
1678   return _free_chunks_total;
1679 }
1680 
1681 size_t ChunkManager::free_chunks_total_bytes() {
1682   return free_chunks_total_words() * BytesPerWord;
1683 }
1684 
1685 size_t ChunkManager::free_chunks_count() {
1686 #ifdef ASSERT
1687   if (!UseConcMarkSweepGC && !SpaceManager::expand_lock()->is_locked()) {
1688     MutexLockerEx cl(SpaceManager::expand_lock(),
1689                      Mutex::_no_safepoint_check_flag);
1690     // This lock is only needed in debug because the verification
1691     // of the _free_chunks_totals walks the list of free chunks
1692     slow_locked_verify_free_chunks_count();
1693   }
1694 #endif
1695   return _free_chunks_count;
1696 }
1697 
1698 void ChunkManager::locked_verify_free_chunks_total() {
1699   assert_lock_strong(SpaceManager::expand_lock());
1700   assert(sum_free_chunks() == _free_chunks_total,
1701     err_msg("_free_chunks_total " SIZE_FORMAT " is not the"
1702            " same as sum " SIZE_FORMAT, _free_chunks_total,
1703            sum_free_chunks()));
1704 }
1705 
1706 void ChunkManager::verify_free_chunks_total() {
1707   MutexLockerEx cl(SpaceManager::expand_lock(),
1708                      Mutex::_no_safepoint_check_flag);
1709   locked_verify_free_chunks_total();
1710 }
1711 
1712 void ChunkManager::locked_verify_free_chunks_count() {
1713   assert_lock_strong(SpaceManager::expand_lock());
1714   assert(sum_free_chunks_count() == _free_chunks_count,
1715     err_msg("_free_chunks_count " SIZE_FORMAT " is not the"
1716            " same as sum " SIZE_FORMAT, _free_chunks_count,
1717            sum_free_chunks_count()));
1718 }
1719 
1720 void ChunkManager::verify_free_chunks_count() {
1721 #ifdef ASSERT
1722   MutexLockerEx cl(SpaceManager::expand_lock(),
1723                      Mutex::_no_safepoint_check_flag);
1724   locked_verify_free_chunks_count();
1725 #endif
1726 }
1727 
1728 void ChunkManager::verify() {
1729   MutexLockerEx cl(SpaceManager::expand_lock(),
1730                      Mutex::_no_safepoint_check_flag);
1731   locked_verify();
1732 }
1733 
1734 void ChunkManager::locked_verify() {
1735   locked_verify_free_chunks_count();
1736   locked_verify_free_chunks_total();
1737 }
1738 
1739 void ChunkManager::locked_print_free_chunks(outputStream* st) {
1740   assert_lock_strong(SpaceManager::expand_lock());
1741   st->print_cr("Free chunk total " SIZE_FORMAT "  count " SIZE_FORMAT,
1742                 _free_chunks_total, _free_chunks_count);
1743 }
1744 
1745 void ChunkManager::locked_print_sum_free_chunks(outputStream* st) {
1746   assert_lock_strong(SpaceManager::expand_lock());
1747   st->print_cr("Sum free chunk total " SIZE_FORMAT "  count " SIZE_FORMAT,
1748                 sum_free_chunks(), sum_free_chunks_count());
1749 }
1750 ChunkList* ChunkManager::free_chunks(ChunkIndex index) {
1751   return &_free_chunks[index];
1752 }
1753 
1754 // These methods that sum the free chunk lists are used in printing
1755 // methods that are used in product builds.
1756 size_t ChunkManager::sum_free_chunks() {
1757   assert_lock_strong(SpaceManager::expand_lock());
1758   size_t result = 0;
1759   for (ChunkIndex i = ZeroIndex; i < NumberOfFreeLists; i = next_chunk_index(i)) {
1760     ChunkList* list = free_chunks(i);
1761 
1762     if (list == NULL) {
1763       continue;
1764     }
1765 
1766     result = result + list->count() * list->size();
1767   }
1768   result = result + humongous_dictionary()->total_size();
1769   return result;
1770 }
1771 
1772 size_t ChunkManager::sum_free_chunks_count() {
1773   assert_lock_strong(SpaceManager::expand_lock());
1774   size_t count = 0;
1775   for (ChunkIndex i = ZeroIndex; i < NumberOfFreeLists; i = next_chunk_index(i)) {
1776     ChunkList* list = free_chunks(i);
1777     if (list == NULL) {
1778       continue;
1779     }
1780     count = count + list->count();
1781   }
1782   count = count + humongous_dictionary()->total_free_blocks();
1783   return count;
1784 }
1785 
1786 ChunkList* ChunkManager::find_free_chunks_list(size_t word_size) {
1787   ChunkIndex index = list_index(word_size);
1788   assert(index < HumongousIndex, "No humongous list");
1789   return free_chunks(index);
1790 }
1791 
1792 Metachunk* ChunkManager::free_chunks_get(size_t word_size) {
1793   assert_lock_strong(SpaceManager::expand_lock());
1794 
1795   slow_locked_verify();
1796 
1797   Metachunk* chunk = NULL;
1798   if (list_index(word_size) != HumongousIndex) {
1799     ChunkList* free_list = find_free_chunks_list(word_size);
1800     assert(free_list != NULL, "Sanity check");
1801 
1802     chunk = free_list->head();
1803 
1804     if (chunk == NULL) {
1805       return NULL;
1806     }
1807 
1808     // Remove the chunk as the head of the list.
1809     free_list->remove_chunk(chunk);
1810 
1811     if (TraceMetadataChunkAllocation && Verbose) {
1812       gclog_or_tty->print_cr("ChunkManager::free_chunks_get: free_list "
1813                              PTR_FORMAT " head " PTR_FORMAT " size " SIZE_FORMAT,
1814                              free_list, chunk, chunk->word_size());
1815     }
1816   } else {
1817     chunk = humongous_dictionary()->get_chunk(
1818       word_size,
1819       FreeBlockDictionary<Metachunk>::atLeast);
1820 
1821     if (chunk == NULL) {
1822       return NULL;
1823     }
1824 
1825     if (TraceMetadataHumongousAllocation) {
1826       size_t waste = chunk->word_size() - word_size;
1827       gclog_or_tty->print_cr("Free list allocate humongous chunk size "
1828                              SIZE_FORMAT " for requested size " SIZE_FORMAT
1829                              " waste " SIZE_FORMAT,
1830                              chunk->word_size(), word_size, waste);
1831     }
1832   }
1833 
1834   // Chunk is being removed from the chunks free list.
1835   dec_free_chunks_total(chunk->word_size());
1836 
1837   // Remove it from the links to this freelist
1838   chunk->set_next(NULL);
1839   chunk->set_prev(NULL);
1840 #ifdef ASSERT
1841   // Chunk is no longer on any freelist. Setting to false make container_count_slow()
1842   // work.
1843   chunk->set_is_tagged_free(false);
1844 #endif
1845   chunk->container()->inc_container_count();
1846 
1847   slow_locked_verify();
1848   return chunk;
1849 }
1850 
1851 Metachunk* ChunkManager::chunk_freelist_allocate(size_t word_size) {
1852   assert_lock_strong(SpaceManager::expand_lock());
1853   slow_locked_verify();
1854 
1855   // Take from the beginning of the list
1856   Metachunk* chunk = free_chunks_get(word_size);
1857   if (chunk == NULL) {
1858     return NULL;
1859   }
1860 
1861   assert((word_size <= chunk->word_size()) ||
1862          list_index(chunk->word_size() == HumongousIndex),
1863          "Non-humongous variable sized chunk");
1864   if (TraceMetadataChunkAllocation) {
1865     size_t list_count;
1866     if (list_index(word_size) < HumongousIndex) {
1867       ChunkList* list = find_free_chunks_list(word_size);
1868       list_count = list->count();
1869     } else {
1870       list_count = humongous_dictionary()->total_count();
1871     }
1872     gclog_or_tty->print("ChunkManager::chunk_freelist_allocate: " PTR_FORMAT " chunk "
1873                         PTR_FORMAT "  size " SIZE_FORMAT " count " SIZE_FORMAT " ",
1874                         this, chunk, chunk->word_size(), list_count);
1875     locked_print_free_chunks(gclog_or_tty);
1876   }
1877 
1878   return chunk;
1879 }
1880 
1881 void ChunkManager::print_on(outputStream* out) const {
1882   if (PrintFLSStatistics != 0) {
1883     const_cast<ChunkManager *>(this)->humongous_dictionary()->report_statistics();
1884   }
1885 }
1886 
1887 // SpaceManager methods
1888 
1889 void SpaceManager::get_initial_chunk_sizes(Metaspace::MetaspaceType type,
1890                                            size_t* chunk_word_size,
1891                                            size_t* class_chunk_word_size) {
1892   switch (type) {
1893   case Metaspace::BootMetaspaceType:
1894     *chunk_word_size = Metaspace::first_chunk_word_size();
1895     *class_chunk_word_size = Metaspace::first_class_chunk_word_size();
1896     break;
1897   case Metaspace::ROMetaspaceType:
1898     *chunk_word_size = SharedReadOnlySize / wordSize;
1899     *class_chunk_word_size = ClassSpecializedChunk;
1900     break;
1901   case Metaspace::ReadWriteMetaspaceType:
1902     *chunk_word_size = SharedReadWriteSize / wordSize;
1903     *class_chunk_word_size = ClassSpecializedChunk;
1904     break;
1905   case Metaspace::AnonymousMetaspaceType:
1906   case Metaspace::ReflectionMetaspaceType:
1907     *chunk_word_size = SpecializedChunk;
1908     *class_chunk_word_size = ClassSpecializedChunk;
1909     break;
1910   default:
1911     *chunk_word_size = SmallChunk;
1912     *class_chunk_word_size = ClassSmallChunk;
1913     break;
1914   }
1915   assert(*chunk_word_size != 0 && *class_chunk_word_size != 0,
1916     err_msg("Initial chunks sizes bad: data  " SIZE_FORMAT
1917             " class " SIZE_FORMAT,
1918             *chunk_word_size, *class_chunk_word_size));
1919 }
1920 
1921 size_t SpaceManager::sum_free_in_chunks_in_use() const {
1922   MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag);
1923   size_t free = 0;
1924   for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) {
1925     Metachunk* chunk = chunks_in_use(i);
1926     while (chunk != NULL) {
1927       free += chunk->free_word_size();
1928       chunk = chunk->next();
1929     }
1930   }
1931   return free;
1932 }
1933 
1934 size_t SpaceManager::sum_waste_in_chunks_in_use() const {
1935   MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag);
1936   size_t result = 0;
1937   for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) {
1938    result += sum_waste_in_chunks_in_use(i);
1939   }
1940 
1941   return result;
1942 }
1943 
1944 size_t SpaceManager::sum_waste_in_chunks_in_use(ChunkIndex index) const {
1945   size_t result = 0;
1946   Metachunk* chunk = chunks_in_use(index);
1947   // Count the free space in all the chunk but not the
1948   // current chunk from which allocations are still being done.
1949   while (chunk != NULL) {
1950     if (chunk != current_chunk()) {
1951       result += chunk->free_word_size();
1952     }
1953     chunk = chunk->next();
1954   }
1955   return result;
1956 }
1957 
1958 size_t SpaceManager::sum_capacity_in_chunks_in_use() const {
1959   // For CMS use "allocated_chunks_words()" which does not need the
1960   // Metaspace lock.  For the other collectors sum over the
1961   // lists.  Use both methods as a check that "allocated_chunks_words()"
1962   // is correct.  That is, sum_capacity_in_chunks() is too expensive
1963   // to use in the product and allocated_chunks_words() should be used
1964   // but allow for  checking that allocated_chunks_words() returns the same
1965   // value as sum_capacity_in_chunks_in_use() which is the definitive
1966   // answer.
1967   if (UseConcMarkSweepGC) {
1968     return allocated_chunks_words();
1969   } else {
1970     MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag);
1971     size_t sum = 0;
1972     for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) {
1973       Metachunk* chunk = chunks_in_use(i);
1974       while (chunk != NULL) {
1975         sum += chunk->word_size();
1976         chunk = chunk->next();
1977       }
1978     }
1979   return sum;
1980   }
1981 }
1982 
1983 size_t SpaceManager::sum_count_in_chunks_in_use() {
1984   size_t count = 0;
1985   for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) {
1986     count = count + sum_count_in_chunks_in_use(i);
1987   }
1988 
1989   return count;
1990 }
1991 
1992 size_t SpaceManager::sum_count_in_chunks_in_use(ChunkIndex i) {
1993   size_t count = 0;
1994   Metachunk* chunk = chunks_in_use(i);
1995   while (chunk != NULL) {
1996     count++;
1997     chunk = chunk->next();
1998   }
1999   return count;
2000 }
2001 
2002 
2003 size_t SpaceManager::sum_used_in_chunks_in_use() const {
2004   MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag);
2005   size_t used = 0;
2006   for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) {
2007     Metachunk* chunk = chunks_in_use(i);
2008     while (chunk != NULL) {
2009       used += chunk->used_word_size();
2010       chunk = chunk->next();
2011     }
2012   }
2013   return used;
2014 }
2015 
2016 void SpaceManager::locked_print_chunks_in_use_on(outputStream* st) const {
2017 
2018   for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) {
2019     Metachunk* chunk = chunks_in_use(i);
2020     st->print("SpaceManager: %s " PTR_FORMAT,
2021                  chunk_size_name(i), chunk);
2022     if (chunk != NULL) {
2023       st->print_cr(" free " SIZE_FORMAT,
2024                    chunk->free_word_size());
2025     } else {
2026       st->cr();
2027     }
2028   }
2029 
2030   chunk_manager()->locked_print_free_chunks(st);
2031   chunk_manager()->locked_print_sum_free_chunks(st);
2032 }
2033 
2034 size_t SpaceManager::calc_chunk_size(size_t word_size) {
2035 
2036   // Decide between a small chunk and a medium chunk.  Up to
2037   // _small_chunk_limit small chunks can be allocated but
2038   // once a medium chunk has been allocated, no more small
2039   // chunks will be allocated.
2040   size_t chunk_word_size;
2041   if (chunks_in_use(MediumIndex) == NULL &&
2042       sum_count_in_chunks_in_use(SmallIndex) < _small_chunk_limit) {
2043     chunk_word_size = (size_t) small_chunk_size();
2044     if (word_size + Metachunk::overhead() > small_chunk_size()) {
2045       chunk_word_size = medium_chunk_size();
2046     }
2047   } else {
2048     chunk_word_size = medium_chunk_size();
2049   }
2050 
2051   // Might still need a humongous chunk.  Enforce
2052   // humongous allocations sizes to be aligned up to
2053   // the smallest chunk size.
2054   size_t if_humongous_sized_chunk =
2055     align_size_up(word_size + Metachunk::overhead(),
2056                   smallest_chunk_size());
2057   chunk_word_size =
2058     MAX2((size_t) chunk_word_size, if_humongous_sized_chunk);
2059 
2060   assert(!SpaceManager::is_humongous(word_size) ||
2061          chunk_word_size == if_humongous_sized_chunk,
2062          err_msg("Size calculation is wrong, word_size " SIZE_FORMAT
2063                  " chunk_word_size " SIZE_FORMAT,
2064                  word_size, chunk_word_size));
2065   if (TraceMetadataHumongousAllocation &&
2066       SpaceManager::is_humongous(word_size)) {
2067     gclog_or_tty->print_cr("Metadata humongous allocation:");
2068     gclog_or_tty->print_cr("  word_size " PTR_FORMAT, word_size);
2069     gclog_or_tty->print_cr("  chunk_word_size " PTR_FORMAT,
2070                            chunk_word_size);
2071     gclog_or_tty->print_cr("    chunk overhead " PTR_FORMAT,
2072                            Metachunk::overhead());
2073   }
2074   return chunk_word_size;
2075 }
2076 
2077 void SpaceManager::track_metaspace_memory_usage() {
2078   if (is_init_completed()) {
2079     if (is_class()) {
2080       MemoryService::track_compressed_class_memory_usage();
2081     }
2082     MemoryService::track_metaspace_memory_usage();
2083   }
2084 }
2085 
2086 MetaWord* SpaceManager::grow_and_allocate(size_t word_size) {
2087   assert(vs_list()->current_virtual_space() != NULL,
2088          "Should have been set");
2089   assert(current_chunk() == NULL ||
2090          current_chunk()->allocate(word_size) == NULL,
2091          "Don't need to expand");
2092   MutexLockerEx cl(SpaceManager::expand_lock(), Mutex::_no_safepoint_check_flag);
2093 
2094   if (TraceMetadataChunkAllocation && Verbose) {
2095     size_t words_left = 0;
2096     size_t words_used = 0;
2097     if (current_chunk() != NULL) {
2098       words_left = current_chunk()->free_word_size();
2099       words_used = current_chunk()->used_word_size();
2100     }
2101     gclog_or_tty->print_cr("SpaceManager::grow_and_allocate for " SIZE_FORMAT
2102                            " words " SIZE_FORMAT " words used " SIZE_FORMAT
2103                            " words left",
2104                             word_size, words_used, words_left);
2105   }
2106 
2107   // Get another chunk out of the virtual space
2108   size_t grow_chunks_by_words = calc_chunk_size(word_size);
2109   Metachunk* next = get_new_chunk(word_size, grow_chunks_by_words);
2110 
2111   MetaWord* mem = NULL;
2112 
2113   // If a chunk was available, add it to the in-use chunk list
2114   // and do an allocation from it.
2115   if (next != NULL) {
2116     // Add to this manager's list of chunks in use.
2117     add_chunk(next, false);
2118     mem = next->allocate(word_size);
2119   }
2120 
2121   // Track metaspace memory usage statistic.
2122   track_metaspace_memory_usage();
2123 
2124   return mem;
2125 }
2126 
2127 void SpaceManager::print_on(outputStream* st) const {
2128 
2129   for (ChunkIndex i = ZeroIndex;
2130        i < NumberOfInUseLists ;
2131        i = next_chunk_index(i) ) {
2132     st->print_cr("  chunks_in_use " PTR_FORMAT " chunk size " PTR_FORMAT,
2133                  chunks_in_use(i),
2134                  chunks_in_use(i) == NULL ? 0 : chunks_in_use(i)->word_size());
2135   }
2136   st->print_cr("    waste:  Small " SIZE_FORMAT " Medium " SIZE_FORMAT
2137                " Humongous " SIZE_FORMAT,
2138                sum_waste_in_chunks_in_use(SmallIndex),
2139                sum_waste_in_chunks_in_use(MediumIndex),
2140                sum_waste_in_chunks_in_use(HumongousIndex));
2141   // block free lists
2142   if (block_freelists() != NULL) {
2143     st->print_cr("total in block free lists " SIZE_FORMAT,
2144       block_freelists()->total_size());
2145   }
2146 }
2147 
2148 SpaceManager::SpaceManager(Metaspace::MetadataType mdtype,
2149                            Mutex* lock) :
2150   _mdtype(mdtype),
2151   _allocated_blocks_words(0),
2152   _allocated_chunks_words(0),
2153   _allocated_chunks_count(0),
2154   _lock(lock)
2155 {
2156   initialize();
2157 }
2158 
2159 void SpaceManager::inc_size_metrics(size_t words) {
2160   assert_lock_strong(SpaceManager::expand_lock());
2161   // Total of allocated Metachunks and allocated Metachunks count
2162   // for each SpaceManager
2163   _allocated_chunks_words = _allocated_chunks_words + words;
2164   _allocated_chunks_count++;
2165   // Global total of capacity in allocated Metachunks
2166   MetaspaceAux::inc_capacity(mdtype(), words);
2167   // Global total of allocated Metablocks.
2168   // used_words_slow() includes the overhead in each
2169   // Metachunk so include it in the used when the
2170   // Metachunk is first added (so only added once per
2171   // Metachunk).
2172   MetaspaceAux::inc_used(mdtype(), Metachunk::overhead());
2173 }
2174 
2175 void SpaceManager::inc_used_metrics(size_t words) {
2176   // Add to the per SpaceManager total
2177   Atomic::add_ptr(words, &_allocated_blocks_words);
2178   // Add to the global total
2179   MetaspaceAux::inc_used(mdtype(), words);
2180 }
2181 
2182 void SpaceManager::dec_total_from_size_metrics() {
2183   MetaspaceAux::dec_capacity(mdtype(), allocated_chunks_words());
2184   MetaspaceAux::dec_used(mdtype(), allocated_blocks_words());
2185   // Also deduct the overhead per Metachunk
2186   MetaspaceAux::dec_used(mdtype(), allocated_chunks_count() * Metachunk::overhead());
2187 }
2188 
2189 void SpaceManager::initialize() {
2190   Metadebug::init_allocation_fail_alot_count();
2191   for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) {
2192     _chunks_in_use[i] = NULL;
2193   }
2194   _current_chunk = NULL;
2195   if (TraceMetadataChunkAllocation && Verbose) {
2196     gclog_or_tty->print_cr("SpaceManager(): " PTR_FORMAT, this);
2197   }
2198 }
2199 
2200 void ChunkManager::return_chunks(ChunkIndex index, Metachunk* chunks) {
2201   if (chunks == NULL) {
2202     return;
2203   }
2204   ChunkList* list = free_chunks(index);
2205   assert(list->size() == chunks->word_size(), "Mismatch in chunk sizes");
2206   assert_lock_strong(SpaceManager::expand_lock());
2207   Metachunk* cur = chunks;
2208 
2209   // This returns chunks one at a time.  If a new
2210   // class List can be created that is a base class
2211   // of FreeList then something like FreeList::prepend()
2212   // can be used in place of this loop
2213   while (cur != NULL) {
2214     assert(cur->container() != NULL, "Container should have been set");
2215     cur->container()->dec_container_count();
2216     // Capture the next link before it is changed
2217     // by the call to return_chunk_at_head();
2218     Metachunk* next = cur->next();
2219     DEBUG_ONLY(cur->set_is_tagged_free(true);)
2220     list->return_chunk_at_head(cur);
2221     cur = next;
2222   }
2223 }
2224 
2225 SpaceManager::~SpaceManager() {
2226   // This call this->_lock which can't be done while holding expand_lock()
2227   assert(sum_capacity_in_chunks_in_use() == allocated_chunks_words(),
2228     err_msg("sum_capacity_in_chunks_in_use() " SIZE_FORMAT
2229             " allocated_chunks_words() " SIZE_FORMAT,
2230             sum_capacity_in_chunks_in_use(), allocated_chunks_words()));
2231 
2232   MutexLockerEx fcl(SpaceManager::expand_lock(),
2233                     Mutex::_no_safepoint_check_flag);
2234 
2235   chunk_manager()->slow_locked_verify();
2236 
2237   dec_total_from_size_metrics();
2238 
2239   if (TraceMetadataChunkAllocation && Verbose) {
2240     gclog_or_tty->print_cr("~SpaceManager(): " PTR_FORMAT, this);
2241     locked_print_chunks_in_use_on(gclog_or_tty);
2242   }
2243 
2244   // Do not mangle freed Metachunks.  The chunk size inside Metachunks
2245   // is during the freeing of a VirtualSpaceNodes.
2246 
2247   // Have to update before the chunks_in_use lists are emptied
2248   // below.
2249   chunk_manager()->inc_free_chunks_total(allocated_chunks_words(),
2250                                          sum_count_in_chunks_in_use());
2251 
2252   // Add all the chunks in use by this space manager
2253   // to the global list of free chunks.
2254 
2255   // Follow each list of chunks-in-use and add them to the
2256   // free lists.  Each list is NULL terminated.
2257 
2258   for (ChunkIndex i = ZeroIndex; i < HumongousIndex; i = next_chunk_index(i)) {
2259     if (TraceMetadataChunkAllocation && Verbose) {
2260       gclog_or_tty->print_cr("returned %d %s chunks to freelist",
2261                              sum_count_in_chunks_in_use(i),
2262                              chunk_size_name(i));
2263     }
2264     Metachunk* chunks = chunks_in_use(i);
2265     chunk_manager()->return_chunks(i, chunks);
2266     set_chunks_in_use(i, NULL);
2267     if (TraceMetadataChunkAllocation && Verbose) {
2268       gclog_or_tty->print_cr("updated freelist count %d %s",
2269                              chunk_manager()->free_chunks(i)->count(),
2270                              chunk_size_name(i));
2271     }
2272     assert(i != HumongousIndex, "Humongous chunks are handled explicitly later");
2273   }
2274 
2275   // The medium chunk case may be optimized by passing the head and
2276   // tail of the medium chunk list to add_at_head().  The tail is often
2277   // the current chunk but there are probably exceptions.
2278 
2279   // Humongous chunks
2280   if (TraceMetadataChunkAllocation && Verbose) {
2281     gclog_or_tty->print_cr("returned %d %s humongous chunks to dictionary",
2282                             sum_count_in_chunks_in_use(HumongousIndex),
2283                             chunk_size_name(HumongousIndex));
2284     gclog_or_tty->print("Humongous chunk dictionary: ");
2285   }
2286   // Humongous chunks are never the current chunk.
2287   Metachunk* humongous_chunks = chunks_in_use(HumongousIndex);
2288 
2289   while (humongous_chunks != NULL) {
2290 #ifdef ASSERT
2291     humongous_chunks->set_is_tagged_free(true);
2292 #endif
2293     if (TraceMetadataChunkAllocation && Verbose) {
2294       gclog_or_tty->print(PTR_FORMAT " (" SIZE_FORMAT ") ",
2295                           humongous_chunks,
2296                           humongous_chunks->word_size());
2297     }
2298     assert(humongous_chunks->word_size() == (size_t)
2299            align_size_up(humongous_chunks->word_size(),
2300                              smallest_chunk_size()),
2301            err_msg("Humongous chunk size is wrong: word size " SIZE_FORMAT
2302                    " granularity %d",
2303                    humongous_chunks->word_size(), smallest_chunk_size()));
2304     Metachunk* next_humongous_chunks = humongous_chunks->next();
2305     humongous_chunks->container()->dec_container_count();
2306     chunk_manager()->humongous_dictionary()->return_chunk(humongous_chunks);
2307     humongous_chunks = next_humongous_chunks;
2308   }
2309   if (TraceMetadataChunkAllocation && Verbose) {
2310     gclog_or_tty->cr();
2311     gclog_or_tty->print_cr("updated dictionary count %d %s",
2312                      chunk_manager()->humongous_dictionary()->total_count(),
2313                      chunk_size_name(HumongousIndex));
2314   }
2315   chunk_manager()->slow_locked_verify();
2316 }
2317 
2318 const char* SpaceManager::chunk_size_name(ChunkIndex index) const {
2319   switch (index) {
2320     case SpecializedIndex:
2321       return "Specialized";
2322     case SmallIndex:
2323       return "Small";
2324     case MediumIndex:
2325       return "Medium";
2326     case HumongousIndex:
2327       return "Humongous";
2328     default:
2329       return NULL;
2330   }
2331 }
2332 
2333 ChunkIndex ChunkManager::list_index(size_t size) {
2334   switch (size) {
2335     case SpecializedChunk:
2336       assert(SpecializedChunk == ClassSpecializedChunk,
2337              "Need branch for ClassSpecializedChunk");
2338       return SpecializedIndex;
2339     case SmallChunk:
2340     case ClassSmallChunk:
2341       return SmallIndex;
2342     case MediumChunk:
2343     case ClassMediumChunk:
2344       return MediumIndex;
2345     default:
2346       assert(size > MediumChunk || size > ClassMediumChunk,
2347              "Not a humongous chunk");
2348       return HumongousIndex;
2349   }
2350 }
2351 
2352 void SpaceManager::deallocate(MetaWord* p, size_t word_size) {
2353   assert_lock_strong(_lock);
2354   size_t raw_word_size = get_raw_word_size(word_size);
2355   size_t min_size = TreeChunk<Metablock, FreeList<Metablock> >::min_size();
2356   assert(raw_word_size >= min_size,
2357          err_msg("Should not deallocate dark matter " SIZE_FORMAT "<" SIZE_FORMAT, word_size, min_size));
2358   block_freelists()->return_block(p, raw_word_size);
2359 }
2360 
2361 // Adds a chunk to the list of chunks in use.
2362 void SpaceManager::add_chunk(Metachunk* new_chunk, bool make_current) {
2363 
2364   assert(new_chunk != NULL, "Should not be NULL");
2365   assert(new_chunk->next() == NULL, "Should not be on a list");
2366 
2367   new_chunk->reset_empty();
2368 
2369   // Find the correct list and and set the current
2370   // chunk for that list.
2371   ChunkIndex index = ChunkManager::list_index(new_chunk->word_size());
2372 
2373   if (index != HumongousIndex) {
2374     retire_current_chunk();
2375     set_current_chunk(new_chunk);
2376     new_chunk->set_next(chunks_in_use(index));
2377     set_chunks_in_use(index, new_chunk);
2378   } else {
2379     // For null class loader data and DumpSharedSpaces, the first chunk isn't
2380     // small, so small will be null.  Link this first chunk as the current
2381     // chunk.
2382     if (make_current) {
2383       // Set as the current chunk but otherwise treat as a humongous chunk.
2384       set_current_chunk(new_chunk);
2385     }
2386     // Link at head.  The _current_chunk only points to a humongous chunk for
2387     // the null class loader metaspace (class and data virtual space managers)
2388     // any humongous chunks so will not point to the tail
2389     // of the humongous chunks list.
2390     new_chunk->set_next(chunks_in_use(HumongousIndex));
2391     set_chunks_in_use(HumongousIndex, new_chunk);
2392 
2393     assert(new_chunk->word_size() > medium_chunk_size(), "List inconsistency");
2394   }
2395 
2396   // Add to the running sum of capacity
2397   inc_size_metrics(new_chunk->word_size());
2398 
2399   assert(new_chunk->is_empty(), "Not ready for reuse");
2400   if (TraceMetadataChunkAllocation && Verbose) {
2401     gclog_or_tty->print("SpaceManager::add_chunk: %d) ",
2402                         sum_count_in_chunks_in_use());
2403     new_chunk->print_on(gclog_or_tty);
2404     chunk_manager()->locked_print_free_chunks(gclog_or_tty);
2405   }
2406 }
2407 
2408 void SpaceManager::retire_current_chunk() {
2409   if (current_chunk() != NULL) {
2410     size_t remaining_words = current_chunk()->free_word_size();
2411     if (remaining_words >= TreeChunk<Metablock, FreeList<Metablock> >::min_size()) {
2412       block_freelists()->return_block(current_chunk()->allocate(remaining_words), remaining_words);
2413       inc_used_metrics(remaining_words);
2414     }
2415   }
2416 }
2417 
2418 Metachunk* SpaceManager::get_new_chunk(size_t word_size,
2419                                        size_t grow_chunks_by_words) {
2420   // Get a chunk from the chunk freelist
2421   Metachunk* next = chunk_manager()->chunk_freelist_allocate(grow_chunks_by_words);
2422 
2423   if (next == NULL) {
2424     next = vs_list()->get_new_chunk(word_size,
2425                                     grow_chunks_by_words,
2426                                     medium_chunk_bunch());
2427   }
2428 
2429   if (TraceMetadataHumongousAllocation && next != NULL &&
2430       SpaceManager::is_humongous(next->word_size())) {
2431     gclog_or_tty->print_cr("  new humongous chunk word size "
2432                            PTR_FORMAT, next->word_size());
2433   }
2434 
2435   return next;
2436 }
2437 
2438 MetaWord* SpaceManager::allocate(size_t word_size) {
2439   MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag);
2440 
2441   size_t raw_word_size = get_raw_word_size(word_size);
2442   BlockFreelist* fl =  block_freelists();
2443   MetaWord* p = NULL;
2444   // Allocation from the dictionary is expensive in the sense that
2445   // the dictionary has to be searched for a size.  Don't allocate
2446   // from the dictionary until it starts to get fat.  Is this
2447   // a reasonable policy?  Maybe an skinny dictionary is fast enough
2448   // for allocations.  Do some profiling.  JJJ
2449   if (fl->total_size() > allocation_from_dictionary_limit) {
2450     p = fl->get_block(raw_word_size);
2451   }
2452   if (p == NULL) {
2453     p = allocate_work(raw_word_size);
2454   }
2455 
2456   return p;
2457 }
2458 
2459 // Returns the address of spaced allocated for "word_size".
2460 // This methods does not know about blocks (Metablocks)
2461 MetaWord* SpaceManager::allocate_work(size_t word_size) {
2462   assert_lock_strong(_lock);
2463 #ifdef ASSERT
2464   if (Metadebug::test_metadata_failure()) {
2465     return NULL;
2466   }
2467 #endif
2468   // Is there space in the current chunk?
2469   MetaWord* result = NULL;
2470 
2471   // For DumpSharedSpaces, only allocate out of the current chunk which is
2472   // never null because we gave it the size we wanted.   Caller reports out
2473   // of memory if this returns null.
2474   if (DumpSharedSpaces) {
2475     assert(current_chunk() != NULL, "should never happen");
2476     inc_used_metrics(word_size);
2477     return current_chunk()->allocate(word_size); // caller handles null result
2478   }
2479 
2480   if (current_chunk() != NULL) {
2481     result = current_chunk()->allocate(word_size);
2482   }
2483 
2484   if (result == NULL) {
2485     result = grow_and_allocate(word_size);
2486   }
2487 
2488   if (result != NULL) {
2489     inc_used_metrics(word_size);
2490     assert(result != (MetaWord*) chunks_in_use(MediumIndex),
2491            "Head of the list is being allocated");
2492   }
2493 
2494   return result;
2495 }
2496 
2497 void SpaceManager::verify() {
2498   // If there are blocks in the dictionary, then
2499   // verification of chunks does not work since
2500   // being in the dictionary alters a chunk.
2501   if (block_freelists()->total_size() == 0) {
2502     for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) {
2503       Metachunk* curr = chunks_in_use(i);
2504       while (curr != NULL) {
2505         curr->verify();
2506         verify_chunk_size(curr);
2507         curr = curr->next();
2508       }
2509     }
2510   }
2511 }
2512 
2513 void SpaceManager::verify_chunk_size(Metachunk* chunk) {
2514   assert(is_humongous(chunk->word_size()) ||
2515          chunk->word_size() == medium_chunk_size() ||
2516          chunk->word_size() == small_chunk_size() ||
2517          chunk->word_size() == specialized_chunk_size(),
2518          "Chunk size is wrong");
2519   return;
2520 }
2521 
2522 #ifdef ASSERT
2523 void SpaceManager::verify_allocated_blocks_words() {
2524   // Verification is only guaranteed at a safepoint.
2525   assert(SafepointSynchronize::is_at_safepoint() || !Universe::is_fully_initialized(),
2526     "Verification can fail if the applications is running");
2527   assert(allocated_blocks_words() == sum_used_in_chunks_in_use(),
2528     err_msg("allocation total is not consistent " SIZE_FORMAT
2529             " vs " SIZE_FORMAT,
2530             allocated_blocks_words(), sum_used_in_chunks_in_use()));
2531 }
2532 
2533 #endif
2534 
2535 void SpaceManager::dump(outputStream* const out) const {
2536   size_t curr_total = 0;
2537   size_t waste = 0;
2538   uint i = 0;
2539   size_t used = 0;
2540   size_t capacity = 0;
2541 
2542   // Add up statistics for all chunks in this SpaceManager.
2543   for (ChunkIndex index = ZeroIndex;
2544        index < NumberOfInUseLists;
2545        index = next_chunk_index(index)) {
2546     for (Metachunk* curr = chunks_in_use(index);
2547          curr != NULL;
2548          curr = curr->next()) {
2549       out->print("%d) ", i++);
2550       curr->print_on(out);
2551       curr_total += curr->word_size();
2552       used += curr->used_word_size();
2553       capacity += curr->word_size();
2554       waste += curr->free_word_size() + curr->overhead();;
2555     }
2556   }
2557 
2558   if (TraceMetadataChunkAllocation && Verbose) {
2559     block_freelists()->print_on(out);
2560   }
2561 
2562   size_t free = current_chunk() == NULL ? 0 : current_chunk()->free_word_size();
2563   // Free space isn't wasted.
2564   waste -= free;
2565 
2566   out->print_cr("total of all chunks "  SIZE_FORMAT " used " SIZE_FORMAT
2567                 " free " SIZE_FORMAT " capacity " SIZE_FORMAT
2568                 " waste " SIZE_FORMAT, curr_total, used, free, capacity, waste);
2569 }
2570 
2571 #ifndef PRODUCT
2572 void SpaceManager::mangle_freed_chunks() {
2573   for (ChunkIndex index = ZeroIndex;
2574        index < NumberOfInUseLists;
2575        index = next_chunk_index(index)) {
2576     for (Metachunk* curr = chunks_in_use(index);
2577          curr != NULL;
2578          curr = curr->next()) {
2579       curr->mangle();
2580     }
2581   }
2582 }
2583 #endif // PRODUCT
2584 
2585 // MetaspaceAux
2586 
2587 
2588 size_t MetaspaceAux::_capacity_words[] = {0, 0};
2589 size_t MetaspaceAux::_used_words[] = {0, 0};
2590 
2591 size_t MetaspaceAux::free_bytes(Metaspace::MetadataType mdtype) {
2592   VirtualSpaceList* list = Metaspace::get_space_list(mdtype);
2593   return list == NULL ? 0 : list->free_bytes();
2594 }
2595 
2596 size_t MetaspaceAux::free_bytes() {
2597   return free_bytes(Metaspace::ClassType) + free_bytes(Metaspace::NonClassType);
2598 }
2599 
2600 void MetaspaceAux::dec_capacity(Metaspace::MetadataType mdtype, size_t words) {
2601   assert_lock_strong(SpaceManager::expand_lock());
2602   assert(words <= capacity_words(mdtype),
2603     err_msg("About to decrement below 0: words " SIZE_FORMAT
2604             " is greater than _capacity_words[%u] " SIZE_FORMAT,
2605             words, mdtype, capacity_words(mdtype)));
2606   _capacity_words[mdtype] -= words;
2607 }
2608 
2609 void MetaspaceAux::inc_capacity(Metaspace::MetadataType mdtype, size_t words) {
2610   assert_lock_strong(SpaceManager::expand_lock());
2611   // Needs to be atomic
2612   _capacity_words[mdtype] += words;
2613 }
2614 
2615 void MetaspaceAux::dec_used(Metaspace::MetadataType mdtype, size_t words) {
2616   assert(words <= used_words(mdtype),
2617     err_msg("About to decrement below 0: words " SIZE_FORMAT
2618             " is greater than _used_words[%u] " SIZE_FORMAT,
2619             words, mdtype, used_words(mdtype)));
2620   // For CMS deallocation of the Metaspaces occurs during the
2621   // sweep which is a concurrent phase.  Protection by the expand_lock()
2622   // is not enough since allocation is on a per Metaspace basis
2623   // and protected by the Metaspace lock.
2624   jlong minus_words = (jlong) - (jlong) words;
2625   Atomic::add_ptr(minus_words, &_used_words[mdtype]);
2626 }
2627 
2628 void MetaspaceAux::inc_used(Metaspace::MetadataType mdtype, size_t words) {
2629   // _used_words tracks allocations for
2630   // each piece of metadata.  Those allocations are
2631   // generally done concurrently by different application
2632   // threads so must be done atomically.
2633   Atomic::add_ptr(words, &_used_words[mdtype]);
2634 }
2635 
2636 size_t MetaspaceAux::used_bytes_slow(Metaspace::MetadataType mdtype) {
2637   size_t used = 0;
2638   ClassLoaderDataGraphMetaspaceIterator iter;
2639   while (iter.repeat()) {
2640     Metaspace* msp = iter.get_next();
2641     // Sum allocated_blocks_words for each metaspace
2642     if (msp != NULL) {
2643       used += msp->used_words_slow(mdtype);
2644     }
2645   }
2646   return used * BytesPerWord;
2647 }
2648 
2649 size_t MetaspaceAux::free_bytes_slow(Metaspace::MetadataType mdtype) {
2650   size_t free = 0;
2651   ClassLoaderDataGraphMetaspaceIterator iter;
2652   while (iter.repeat()) {
2653     Metaspace* msp = iter.get_next();
2654     if (msp != NULL) {
2655       free += msp->free_words_slow(mdtype);
2656     }
2657   }
2658   return free * BytesPerWord;
2659 }
2660 
2661 size_t MetaspaceAux::capacity_bytes_slow(Metaspace::MetadataType mdtype) {
2662   if ((mdtype == Metaspace::ClassType) && !Metaspace::using_class_space()) {
2663     return 0;
2664   }
2665   // Don't count the space in the freelists.  That space will be
2666   // added to the capacity calculation as needed.
2667   size_t capacity = 0;
2668   ClassLoaderDataGraphMetaspaceIterator iter;
2669   while (iter.repeat()) {
2670     Metaspace* msp = iter.get_next();
2671     if (msp != NULL) {
2672       capacity += msp->capacity_words_slow(mdtype);
2673     }
2674   }
2675   return capacity * BytesPerWord;
2676 }
2677 
2678 size_t MetaspaceAux::capacity_bytes_slow() {
2679 #ifdef PRODUCT
2680   // Use capacity_bytes() in PRODUCT instead of this function.
2681   guarantee(false, "Should not call capacity_bytes_slow() in the PRODUCT");
2682 #endif
2683   size_t class_capacity = capacity_bytes_slow(Metaspace::ClassType);
2684   size_t non_class_capacity = capacity_bytes_slow(Metaspace::NonClassType);
2685   assert(capacity_bytes() == class_capacity + non_class_capacity,
2686       err_msg("bad accounting: capacity_bytes() " SIZE_FORMAT
2687         " class_capacity + non_class_capacity " SIZE_FORMAT
2688         " class_capacity " SIZE_FORMAT " non_class_capacity " SIZE_FORMAT,
2689         capacity_bytes(), class_capacity + non_class_capacity,
2690         class_capacity, non_class_capacity));
2691 
2692   return class_capacity + non_class_capacity;
2693 }
2694 
2695 size_t MetaspaceAux::reserved_bytes(Metaspace::MetadataType mdtype) {
2696   VirtualSpaceList* list = Metaspace::get_space_list(mdtype);
2697   return list == NULL ? 0 : list->reserved_bytes();
2698 }
2699 
2700 size_t MetaspaceAux::committed_bytes(Metaspace::MetadataType mdtype) {
2701   VirtualSpaceList* list = Metaspace::get_space_list(mdtype);
2702   return list == NULL ? 0 : list->committed_bytes();
2703 }
2704 
2705 size_t MetaspaceAux::min_chunk_size_words() { return Metaspace::first_chunk_word_size(); }
2706 
2707 size_t MetaspaceAux::free_chunks_total_words(Metaspace::MetadataType mdtype) {
2708   ChunkManager* chunk_manager = Metaspace::get_chunk_manager(mdtype);
2709   if (chunk_manager == NULL) {
2710     return 0;
2711   }
2712   chunk_manager->slow_verify();
2713   return chunk_manager->free_chunks_total_words();
2714 }
2715 
2716 size_t MetaspaceAux::free_chunks_total_bytes(Metaspace::MetadataType mdtype) {
2717   return free_chunks_total_words(mdtype) * BytesPerWord;
2718 }
2719 
2720 size_t MetaspaceAux::free_chunks_total_words() {
2721   return free_chunks_total_words(Metaspace::ClassType) +
2722          free_chunks_total_words(Metaspace::NonClassType);
2723 }
2724 
2725 size_t MetaspaceAux::free_chunks_total_bytes() {
2726   return free_chunks_total_words() * BytesPerWord;
2727 }
2728 
2729 bool MetaspaceAux::has_chunk_free_list(Metaspace::MetadataType mdtype) {
2730   return Metaspace::get_chunk_manager(mdtype) != NULL;
2731 }
2732 
2733 MetaspaceChunkFreeListSummary MetaspaceAux::chunk_free_list_summary(Metaspace::MetadataType mdtype) {
2734   if (!has_chunk_free_list(mdtype)) {
2735     return MetaspaceChunkFreeListSummary();
2736   }
2737 
2738   const ChunkManager* cm = Metaspace::get_chunk_manager(mdtype);
2739   return cm->chunk_free_list_summary();
2740 }
2741 
2742 void MetaspaceAux::print_metaspace_change(size_t prev_metadata_used) {
2743   gclog_or_tty->print(", [Metaspace:");
2744   if (PrintGCDetails && Verbose) {
2745     gclog_or_tty->print(" "  SIZE_FORMAT
2746                         "->" SIZE_FORMAT
2747                         "("  SIZE_FORMAT ")",
2748                         prev_metadata_used,
2749                         used_bytes(),
2750                         reserved_bytes());
2751   } else {
2752     gclog_or_tty->print(" "  SIZE_FORMAT "K"
2753                         "->" SIZE_FORMAT "K"
2754                         "("  SIZE_FORMAT "K)",
2755                         prev_metadata_used/K,
2756                         used_bytes()/K,
2757                         reserved_bytes()/K);
2758   }
2759 
2760   gclog_or_tty->print("]");
2761 }
2762 
2763 // This is printed when PrintGCDetails
2764 void MetaspaceAux::print_on(outputStream* out) {
2765   Metaspace::MetadataType nct = Metaspace::NonClassType;
2766 
2767   out->print_cr(" Metaspace       "
2768                 "used "      SIZE_FORMAT "K, "
2769                 "capacity "  SIZE_FORMAT "K, "
2770                 "committed " SIZE_FORMAT "K, "
2771                 "reserved "  SIZE_FORMAT "K",
2772                 used_bytes()/K,
2773                 capacity_bytes()/K,
2774                 committed_bytes()/K,
2775                 reserved_bytes()/K);
2776 
2777   if (Metaspace::using_class_space()) {
2778     Metaspace::MetadataType ct = Metaspace::ClassType;
2779     out->print_cr("  class space    "
2780                   "used "      SIZE_FORMAT "K, "
2781                   "capacity "  SIZE_FORMAT "K, "
2782                   "committed " SIZE_FORMAT "K, "
2783                   "reserved "  SIZE_FORMAT "K",
2784                   used_bytes(ct)/K,
2785                   capacity_bytes(ct)/K,
2786                   committed_bytes(ct)/K,
2787                   reserved_bytes(ct)/K);
2788   }
2789 }
2790 
2791 // Print information for class space and data space separately.
2792 // This is almost the same as above.
2793 void MetaspaceAux::print_on(outputStream* out, Metaspace::MetadataType mdtype) {
2794   size_t free_chunks_capacity_bytes = free_chunks_total_bytes(mdtype);
2795   size_t capacity_bytes = capacity_bytes_slow(mdtype);
2796   size_t used_bytes = used_bytes_slow(mdtype);
2797   size_t free_bytes = free_bytes_slow(mdtype);
2798   size_t used_and_free = used_bytes + free_bytes +
2799                            free_chunks_capacity_bytes;
2800   out->print_cr("  Chunk accounting: used in chunks " SIZE_FORMAT
2801              "K + unused in chunks " SIZE_FORMAT "K  + "
2802              " capacity in free chunks " SIZE_FORMAT "K = " SIZE_FORMAT
2803              "K  capacity in allocated chunks " SIZE_FORMAT "K",
2804              used_bytes / K,
2805              free_bytes / K,
2806              free_chunks_capacity_bytes / K,
2807              used_and_free / K,
2808              capacity_bytes / K);
2809   // Accounting can only be correct if we got the values during a safepoint
2810   assert(!SafepointSynchronize::is_at_safepoint() || used_and_free == capacity_bytes, "Accounting is wrong");
2811 }
2812 
2813 // Print total fragmentation for class metaspaces
2814 void MetaspaceAux::print_class_waste(outputStream* out) {
2815   assert(Metaspace::using_class_space(), "class metaspace not used");
2816   size_t cls_specialized_waste = 0, cls_small_waste = 0, cls_medium_waste = 0;
2817   size_t cls_specialized_count = 0, cls_small_count = 0, cls_medium_count = 0, cls_humongous_count = 0;
2818   ClassLoaderDataGraphMetaspaceIterator iter;
2819   while (iter.repeat()) {
2820     Metaspace* msp = iter.get_next();
2821     if (msp != NULL) {
2822       cls_specialized_waste += msp->class_vsm()->sum_waste_in_chunks_in_use(SpecializedIndex);
2823       cls_specialized_count += msp->class_vsm()->sum_count_in_chunks_in_use(SpecializedIndex);
2824       cls_small_waste += msp->class_vsm()->sum_waste_in_chunks_in_use(SmallIndex);
2825       cls_small_count += msp->class_vsm()->sum_count_in_chunks_in_use(SmallIndex);
2826       cls_medium_waste += msp->class_vsm()->sum_waste_in_chunks_in_use(MediumIndex);
2827       cls_medium_count += msp->class_vsm()->sum_count_in_chunks_in_use(MediumIndex);
2828       cls_humongous_count += msp->class_vsm()->sum_count_in_chunks_in_use(HumongousIndex);
2829     }
2830   }
2831   out->print_cr(" class: " SIZE_FORMAT " specialized(s) " SIZE_FORMAT ", "
2832                 SIZE_FORMAT " small(s) " SIZE_FORMAT ", "
2833                 SIZE_FORMAT " medium(s) " SIZE_FORMAT ", "
2834                 "large count " SIZE_FORMAT,
2835                 cls_specialized_count, cls_specialized_waste,
2836                 cls_small_count, cls_small_waste,
2837                 cls_medium_count, cls_medium_waste, cls_humongous_count);
2838 }
2839 
2840 // Print total fragmentation for data and class metaspaces separately
2841 void MetaspaceAux::print_waste(outputStream* out) {
2842   size_t specialized_waste = 0, small_waste = 0, medium_waste = 0;
2843   size_t specialized_count = 0, small_count = 0, medium_count = 0, humongous_count = 0;
2844 
2845   ClassLoaderDataGraphMetaspaceIterator iter;
2846   while (iter.repeat()) {
2847     Metaspace* msp = iter.get_next();
2848     if (msp != NULL) {
2849       specialized_waste += msp->vsm()->sum_waste_in_chunks_in_use(SpecializedIndex);
2850       specialized_count += msp->vsm()->sum_count_in_chunks_in_use(SpecializedIndex);
2851       small_waste += msp->vsm()->sum_waste_in_chunks_in_use(SmallIndex);
2852       small_count += msp->vsm()->sum_count_in_chunks_in_use(SmallIndex);
2853       medium_waste += msp->vsm()->sum_waste_in_chunks_in_use(MediumIndex);
2854       medium_count += msp->vsm()->sum_count_in_chunks_in_use(MediumIndex);
2855       humongous_count += msp->vsm()->sum_count_in_chunks_in_use(HumongousIndex);
2856     }
2857   }
2858   out->print_cr("Total fragmentation waste (words) doesn't count free space");
2859   out->print_cr("  data: " SIZE_FORMAT " specialized(s) " SIZE_FORMAT ", "
2860                         SIZE_FORMAT " small(s) " SIZE_FORMAT ", "
2861                         SIZE_FORMAT " medium(s) " SIZE_FORMAT ", "
2862                         "large count " SIZE_FORMAT,
2863              specialized_count, specialized_waste, small_count,
2864              small_waste, medium_count, medium_waste, humongous_count);
2865   if (Metaspace::using_class_space()) {
2866     print_class_waste(out);
2867   }
2868 }
2869 
2870 // Dump global metaspace things from the end of ClassLoaderDataGraph
2871 void MetaspaceAux::dump(outputStream* out) {
2872   out->print_cr("All Metaspace:");
2873   out->print("data space: "); print_on(out, Metaspace::NonClassType);
2874   out->print("class space: "); print_on(out, Metaspace::ClassType);
2875   print_waste(out);
2876 }
2877 
2878 void MetaspaceAux::verify_free_chunks() {
2879   Metaspace::chunk_manager_metadata()->verify();
2880   if (Metaspace::using_class_space()) {
2881     Metaspace::chunk_manager_class()->verify();
2882   }
2883 }
2884 
2885 void MetaspaceAux::verify_capacity() {
2886 #ifdef ASSERT
2887   size_t running_sum_capacity_bytes = capacity_bytes();
2888   // For purposes of the running sum of capacity, verify against capacity
2889   size_t capacity_in_use_bytes = capacity_bytes_slow();
2890   assert(running_sum_capacity_bytes == capacity_in_use_bytes,
2891     err_msg("capacity_words() * BytesPerWord " SIZE_FORMAT
2892             " capacity_bytes_slow()" SIZE_FORMAT,
2893             running_sum_capacity_bytes, capacity_in_use_bytes));
2894   for (Metaspace::MetadataType i = Metaspace::ClassType;
2895        i < Metaspace:: MetadataTypeCount;
2896        i = (Metaspace::MetadataType)(i + 1)) {
2897     size_t capacity_in_use_bytes = capacity_bytes_slow(i);
2898     assert(capacity_bytes(i) == capacity_in_use_bytes,
2899       err_msg("capacity_bytes(%u) " SIZE_FORMAT
2900               " capacity_bytes_slow(%u)" SIZE_FORMAT,
2901               i, capacity_bytes(i), i, capacity_in_use_bytes));
2902   }
2903 #endif
2904 }
2905 
2906 void MetaspaceAux::verify_used() {
2907 #ifdef ASSERT
2908   size_t running_sum_used_bytes = used_bytes();
2909   // For purposes of the running sum of used, verify against used
2910   size_t used_in_use_bytes = used_bytes_slow();
2911   assert(used_bytes() == used_in_use_bytes,
2912     err_msg("used_bytes() " SIZE_FORMAT
2913             " used_bytes_slow()" SIZE_FORMAT,
2914             used_bytes(), used_in_use_bytes));
2915   for (Metaspace::MetadataType i = Metaspace::ClassType;
2916        i < Metaspace:: MetadataTypeCount;
2917        i = (Metaspace::MetadataType)(i + 1)) {
2918     size_t used_in_use_bytes = used_bytes_slow(i);
2919     assert(used_bytes(i) == used_in_use_bytes,
2920       err_msg("used_bytes(%u) " SIZE_FORMAT
2921               " used_bytes_slow(%u)" SIZE_FORMAT,
2922               i, used_bytes(i), i, used_in_use_bytes));
2923   }
2924 #endif
2925 }
2926 
2927 void MetaspaceAux::verify_metrics() {
2928   verify_capacity();
2929   verify_used();
2930 }
2931 
2932 
2933 // Metaspace methods
2934 
2935 size_t Metaspace::_first_chunk_word_size = 0;
2936 size_t Metaspace::_first_class_chunk_word_size = 0;
2937 
2938 size_t Metaspace::_commit_alignment = 0;
2939 size_t Metaspace::_reserve_alignment = 0;
2940 
2941 Metaspace::Metaspace(Mutex* lock, MetaspaceType type) {
2942   initialize(lock, type);
2943 }
2944 
2945 Metaspace::~Metaspace() {
2946   delete _vsm;
2947   if (using_class_space()) {
2948     delete _class_vsm;
2949   }
2950 }
2951 
2952 VirtualSpaceList* Metaspace::_space_list = NULL;
2953 VirtualSpaceList* Metaspace::_class_space_list = NULL;
2954 
2955 ChunkManager* Metaspace::_chunk_manager_metadata = NULL;
2956 ChunkManager* Metaspace::_chunk_manager_class = NULL;
2957 
2958 #define VIRTUALSPACEMULTIPLIER 2
2959 
2960 #ifdef _LP64
2961 static const uint64_t UnscaledClassSpaceMax = (uint64_t(max_juint) + 1);
2962 
2963 void Metaspace::set_narrow_klass_base_and_shift(address metaspace_base, address cds_base) {
2964   // Figure out the narrow_klass_base and the narrow_klass_shift.  The
2965   // narrow_klass_base is the lower of the metaspace base and the cds base
2966   // (if cds is enabled).  The narrow_klass_shift depends on the distance
2967   // between the lower base and higher address.
2968   address lower_base;
2969   address higher_address;
2970 #if INCLUDE_CDS
2971   if (UseSharedSpaces) {
2972     higher_address = MAX2((address)(cds_base + FileMapInfo::shared_spaces_size()),
2973                           (address)(metaspace_base + compressed_class_space_size()));
2974     lower_base = MIN2(metaspace_base, cds_base);
2975   } else
2976 #endif
2977   {
2978     higher_address = metaspace_base + compressed_class_space_size();
2979     lower_base = metaspace_base;
2980 
2981     uint64_t klass_encoding_max = UnscaledClassSpaceMax << LogKlassAlignmentInBytes;
2982     // If compressed class space fits in lower 32G, we don't need a base.
2983     if (higher_address <= (address)klass_encoding_max) {
2984       lower_base = 0; // Effectively lower base is zero.
2985     }
2986   }
2987 
2988   Universe::set_narrow_klass_base(lower_base);
2989 
2990   if ((uint64_t)(higher_address - lower_base) <= UnscaledClassSpaceMax) {
2991     Universe::set_narrow_klass_shift(0);
2992   } else {
2993     assert(!UseSharedSpaces, "Cannot shift with UseSharedSpaces");
2994     Universe::set_narrow_klass_shift(LogKlassAlignmentInBytes);
2995   }
2996 }
2997 
2998 #if INCLUDE_CDS
2999 // Return TRUE if the specified metaspace_base and cds_base are close enough
3000 // to work with compressed klass pointers.
3001 bool Metaspace::can_use_cds_with_metaspace_addr(char* metaspace_base, address cds_base) {
3002   assert(cds_base != 0 && UseSharedSpaces, "Only use with CDS");
3003   assert(UseCompressedClassPointers, "Only use with CompressedKlassPtrs");
3004   address lower_base = MIN2((address)metaspace_base, cds_base);
3005   address higher_address = MAX2((address)(cds_base + FileMapInfo::shared_spaces_size()),
3006                                 (address)(metaspace_base + compressed_class_space_size()));
3007   return ((uint64_t)(higher_address - lower_base) <= UnscaledClassSpaceMax);
3008 }
3009 #endif
3010 
3011 // Try to allocate the metaspace at the requested addr.
3012 void Metaspace::allocate_metaspace_compressed_klass_ptrs(char* requested_addr, address cds_base) {
3013   assert(using_class_space(), "called improperly");
3014   assert(UseCompressedClassPointers, "Only use with CompressedKlassPtrs");
3015   assert(compressed_class_space_size() < KlassEncodingMetaspaceMax,
3016          "Metaspace size is too big");
3017   assert_is_ptr_aligned(requested_addr, _reserve_alignment);
3018   assert_is_ptr_aligned(cds_base, _reserve_alignment);
3019   assert_is_size_aligned(compressed_class_space_size(), _reserve_alignment);
3020 
3021   // Don't use large pages for the class space.
3022   bool large_pages = false;
3023 
3024   ReservedSpace metaspace_rs = ReservedSpace(compressed_class_space_size(),
3025                                              _reserve_alignment,
3026                                              large_pages,
3027                                              requested_addr, 0);
3028   if (!metaspace_rs.is_reserved()) {
3029 #if INCLUDE_CDS
3030     if (UseSharedSpaces) {
3031       size_t increment = align_size_up(1*G, _reserve_alignment);
3032 
3033       // Keep trying to allocate the metaspace, increasing the requested_addr
3034       // by 1GB each time, until we reach an address that will no longer allow
3035       // use of CDS with compressed klass pointers.
3036       char *addr = requested_addr;
3037       while (!metaspace_rs.is_reserved() && (addr + increment > addr) &&
3038              can_use_cds_with_metaspace_addr(addr + increment, cds_base)) {
3039         addr = addr + increment;
3040         metaspace_rs = ReservedSpace(compressed_class_space_size(),
3041                                      _reserve_alignment, large_pages, addr, 0);
3042       }
3043     }
3044 #endif
3045     // If no successful allocation then try to allocate the space anywhere.  If
3046     // that fails then OOM doom.  At this point we cannot try allocating the
3047     // metaspace as if UseCompressedClassPointers is off because too much
3048     // initialization has happened that depends on UseCompressedClassPointers.
3049     // So, UseCompressedClassPointers cannot be turned off at this point.
3050     if (!metaspace_rs.is_reserved()) {
3051       metaspace_rs = ReservedSpace(compressed_class_space_size(),
3052                                    _reserve_alignment, large_pages);
3053       if (!metaspace_rs.is_reserved()) {
3054         vm_exit_during_initialization(err_msg("Could not allocate metaspace: %d bytes",
3055                                               compressed_class_space_size()));
3056       }
3057     }
3058   }
3059 
3060   // If we got here then the metaspace got allocated.
3061   MemTracker::record_virtual_memory_type((address)metaspace_rs.base(), mtClass);
3062 
3063 #if INCLUDE_CDS
3064   // Verify that we can use shared spaces.  Otherwise, turn off CDS.
3065   if (UseSharedSpaces && !can_use_cds_with_metaspace_addr(metaspace_rs.base(), cds_base)) {
3066     FileMapInfo::stop_sharing_and_unmap(
3067         "Could not allocate metaspace at a compatible address");
3068   }
3069 #endif
3070   set_narrow_klass_base_and_shift((address)metaspace_rs.base(),
3071                                   UseSharedSpaces ? (address)cds_base : 0);
3072 
3073   initialize_class_space(metaspace_rs);
3074 
3075   if (PrintCompressedOopsMode || (PrintMiscellaneous && Verbose)) {
3076     gclog_or_tty->print_cr("Narrow klass base: " PTR_FORMAT ", Narrow klass shift: " SIZE_FORMAT,
3077                             Universe::narrow_klass_base(), Universe::narrow_klass_shift());
3078     gclog_or_tty->print_cr("Compressed class space size: " SIZE_FORMAT " Address: " PTR_FORMAT " Req Addr: " PTR_FORMAT,
3079                            compressed_class_space_size(), metaspace_rs.base(), requested_addr);
3080   }
3081 }
3082 
3083 // For UseCompressedClassPointers the class space is reserved above the top of
3084 // the Java heap.  The argument passed in is at the base of the compressed space.
3085 void Metaspace::initialize_class_space(ReservedSpace rs) {
3086   // The reserved space size may be bigger because of alignment, esp with UseLargePages
3087   assert(rs.size() >= CompressedClassSpaceSize,
3088          err_msg(SIZE_FORMAT " != " UINTX_FORMAT, rs.size(), CompressedClassSpaceSize));
3089   assert(using_class_space(), "Must be using class space");
3090   _class_space_list = new VirtualSpaceList(rs);
3091   _chunk_manager_class = new ChunkManager(SpecializedChunk, ClassSmallChunk, ClassMediumChunk);
3092 
3093   if (!_class_space_list->initialization_succeeded()) {
3094     vm_exit_during_initialization("Failed to setup compressed class space virtual space list.");
3095   }
3096 }
3097 
3098 #endif
3099 
3100 void Metaspace::ergo_initialize() {
3101   if (DumpSharedSpaces) {
3102     // Using large pages when dumping the shared archive is currently not implemented.
3103     FLAG_SET_ERGO(bool, UseLargePagesInMetaspace, false);
3104   }
3105 
3106   size_t page_size = os::vm_page_size();
3107   if (UseLargePages && UseLargePagesInMetaspace) {
3108     page_size = os::large_page_size();
3109   }
3110 
3111   _commit_alignment  = page_size;
3112   _reserve_alignment = MAX2(page_size, (size_t)os::vm_allocation_granularity());
3113 
3114   // Do not use FLAG_SET_ERGO to update MaxMetaspaceSize, since this will
3115   // override if MaxMetaspaceSize was set on the command line or not.
3116   // This information is needed later to conform to the specification of the
3117   // java.lang.management.MemoryUsage API.
3118   //
3119   // Ideally, we would be able to set the default value of MaxMetaspaceSize in
3120   // globals.hpp to the aligned value, but this is not possible, since the
3121   // alignment depends on other flags being parsed.
3122   MaxMetaspaceSize = align_size_down_bounded(MaxMetaspaceSize, _reserve_alignment);
3123 
3124   if (MetaspaceSize > MaxMetaspaceSize) {
3125     MetaspaceSize = MaxMetaspaceSize;
3126   }
3127 
3128   MetaspaceSize = align_size_down_bounded(MetaspaceSize, _commit_alignment);
3129 
3130   assert(MetaspaceSize <= MaxMetaspaceSize, "MetaspaceSize should be limited by MaxMetaspaceSize");
3131 
3132   if (MetaspaceSize < 256*K) {
3133     vm_exit_during_initialization("Too small initial Metaspace size");
3134   }
3135 
3136   MinMetaspaceExpansion = align_size_down_bounded(MinMetaspaceExpansion, _commit_alignment);
3137   MaxMetaspaceExpansion = align_size_down_bounded(MaxMetaspaceExpansion, _commit_alignment);
3138 
3139   CompressedClassSpaceSize = align_size_down_bounded(CompressedClassSpaceSize, _reserve_alignment);
3140   set_compressed_class_space_size(CompressedClassSpaceSize);
3141 }
3142 
3143 void Metaspace::global_initialize() {
3144   MetaspaceGC::initialize();
3145 
3146   // Initialize the alignment for shared spaces.
3147   int max_alignment = os::vm_allocation_granularity();
3148   size_t cds_total = 0;
3149 
3150   MetaspaceShared::set_max_alignment(max_alignment);
3151 
3152   if (DumpSharedSpaces) {
3153 #if INCLUDE_CDS
3154     MetaspaceShared::estimate_regions_size();
3155 
3156     SharedReadOnlySize  = align_size_up(SharedReadOnlySize,  max_alignment);
3157     SharedReadWriteSize = align_size_up(SharedReadWriteSize, max_alignment);
3158     SharedMiscDataSize  = align_size_up(SharedMiscDataSize,  max_alignment);
3159     SharedMiscCodeSize  = align_size_up(SharedMiscCodeSize,  max_alignment);
3160 
3161     // the min_misc_code_size estimate is based on MetaspaceShared::generate_vtable_methods()
3162     uintx min_misc_code_size = align_size_up(
3163       (MetaspaceShared::num_virtuals * MetaspaceShared::vtbl_list_size) *
3164         (sizeof(void*) + MetaspaceShared::vtbl_method_size) + MetaspaceShared::vtbl_common_code_size,
3165           max_alignment);
3166 
3167     if (SharedMiscCodeSize < min_misc_code_size) {
3168       report_out_of_shared_space(SharedMiscCode);
3169     }
3170 
3171     // Initialize with the sum of the shared space sizes.  The read-only
3172     // and read write metaspace chunks will be allocated out of this and the
3173     // remainder is the misc code and data chunks.
3174     cds_total = FileMapInfo::shared_spaces_size();
3175     cds_total = align_size_up(cds_total, _reserve_alignment);
3176     _space_list = new VirtualSpaceList(cds_total/wordSize);
3177     _chunk_manager_metadata = new ChunkManager(SpecializedChunk, SmallChunk, MediumChunk);
3178 
3179     if (!_space_list->initialization_succeeded()) {
3180       vm_exit_during_initialization("Unable to dump shared archive.", NULL);
3181     }
3182 
3183 #ifdef _LP64
3184     if (cds_total + compressed_class_space_size() > UnscaledClassSpaceMax) {
3185       vm_exit_during_initialization("Unable to dump shared archive.",
3186           err_msg("Size of archive (" SIZE_FORMAT ") + compressed class space ("
3187                   SIZE_FORMAT ") == total (" SIZE_FORMAT ") is larger than compressed "
3188                   "klass limit: " SIZE_FORMAT, cds_total, compressed_class_space_size(),
3189                   cds_total + compressed_class_space_size(), UnscaledClassSpaceMax));
3190     }
3191 
3192     // Set the compressed klass pointer base so that decoding of these pointers works
3193     // properly when creating the shared archive.
3194     assert(UseCompressedOops && UseCompressedClassPointers,
3195       "UseCompressedOops and UseCompressedClassPointers must be set");
3196     Universe::set_narrow_klass_base((address)_space_list->current_virtual_space()->bottom());
3197     if (TraceMetavirtualspaceAllocation && Verbose) {
3198       gclog_or_tty->print_cr("Setting_narrow_klass_base to Address: " PTR_FORMAT,
3199                              _space_list->current_virtual_space()->bottom());
3200     }
3201 
3202     Universe::set_narrow_klass_shift(0);
3203 #endif // _LP64
3204 #endif // INCLUDE_CDS
3205   } else {
3206 #if INCLUDE_CDS
3207     // If using shared space, open the file that contains the shared space
3208     // and map in the memory before initializing the rest of metaspace (so
3209     // the addresses don't conflict)
3210     address cds_address = NULL;
3211     if (UseSharedSpaces) {
3212       FileMapInfo* mapinfo = new FileMapInfo();
3213 
3214       // Open the shared archive file, read and validate the header. If
3215       // initialization fails, shared spaces [UseSharedSpaces] are
3216       // disabled and the file is closed.
3217       // Map in spaces now also
3218       if (mapinfo->initialize() && MetaspaceShared::map_shared_spaces(mapinfo)) {
3219         cds_total = FileMapInfo::shared_spaces_size();
3220         cds_address = (address)mapinfo->region_base(0);
3221       } else {
3222         assert(!mapinfo->is_open() && !UseSharedSpaces,
3223                "archive file not closed or shared spaces not disabled.");
3224       }
3225     }
3226 #endif // INCLUDE_CDS
3227 #ifdef _LP64
3228     // If UseCompressedClassPointers is set then allocate the metaspace area
3229     // above the heap and above the CDS area (if it exists).
3230     if (using_class_space()) {
3231       if (UseSharedSpaces) {
3232 #if INCLUDE_CDS
3233         char* cds_end = (char*)(cds_address + cds_total);
3234         cds_end = (char *)align_ptr_up(cds_end, _reserve_alignment);
3235         allocate_metaspace_compressed_klass_ptrs(cds_end, cds_address);
3236 #endif
3237       } else {
3238         char* base = (char*)align_ptr_up(Universe::heap()->reserved_region().end(), _reserve_alignment);
3239         allocate_metaspace_compressed_klass_ptrs(base, 0);
3240       }
3241     }
3242 #endif // _LP64
3243 
3244     // Initialize these before initializing the VirtualSpaceList
3245     _first_chunk_word_size = InitialBootClassLoaderMetaspaceSize / BytesPerWord;
3246     _first_chunk_word_size = align_word_size_up(_first_chunk_word_size);
3247     // Make the first class chunk bigger than a medium chunk so it's not put
3248     // on the medium chunk list.   The next chunk will be small and progress
3249     // from there.  This size calculated by -version.
3250     _first_class_chunk_word_size = MIN2((size_t)MediumChunk*6,
3251                                        (CompressedClassSpaceSize/BytesPerWord)*2);
3252     _first_class_chunk_word_size = align_word_size_up(_first_class_chunk_word_size);
3253     // Arbitrarily set the initial virtual space to a multiple
3254     // of the boot class loader size.
3255     size_t word_size = VIRTUALSPACEMULTIPLIER * _first_chunk_word_size;
3256     word_size = align_size_up(word_size, Metaspace::reserve_alignment_words());
3257 
3258     // Initialize the list of virtual spaces.
3259     _space_list = new VirtualSpaceList(word_size);
3260     _chunk_manager_metadata = new ChunkManager(SpecializedChunk, SmallChunk, MediumChunk);
3261 
3262     if (!_space_list->initialization_succeeded()) {
3263       vm_exit_during_initialization("Unable to setup metadata virtual space list.", NULL);
3264     }
3265   }
3266 
3267   _tracer = new MetaspaceTracer();
3268 }
3269 
3270 void Metaspace::post_initialize() {
3271   MetaspaceGC::post_initialize();
3272 }
3273 
3274 Metachunk* Metaspace::get_initialization_chunk(MetadataType mdtype,
3275                                                size_t chunk_word_size,
3276                                                size_t chunk_bunch) {
3277   // Get a chunk from the chunk freelist
3278   Metachunk* chunk = get_chunk_manager(mdtype)->chunk_freelist_allocate(chunk_word_size);
3279   if (chunk != NULL) {
3280     return chunk;
3281   }
3282 
3283   return get_space_list(mdtype)->get_new_chunk(chunk_word_size, chunk_word_size, chunk_bunch);
3284 }
3285 
3286 void Metaspace::initialize(Mutex* lock, MetaspaceType type) {
3287 
3288   assert(space_list() != NULL,
3289     "Metadata VirtualSpaceList has not been initialized");
3290   assert(chunk_manager_metadata() != NULL,
3291     "Metadata ChunkManager has not been initialized");
3292 
3293   _vsm = new SpaceManager(NonClassType, lock);
3294   if (_vsm == NULL) {
3295     return;
3296   }
3297   size_t word_size;
3298   size_t class_word_size;
3299   vsm()->get_initial_chunk_sizes(type, &word_size, &class_word_size);
3300 
3301   if (using_class_space()) {
3302   assert(class_space_list() != NULL,
3303     "Class VirtualSpaceList has not been initialized");
3304   assert(chunk_manager_class() != NULL,
3305     "Class ChunkManager has not been initialized");
3306 
3307     // Allocate SpaceManager for classes.
3308     _class_vsm = new SpaceManager(ClassType, lock);
3309     if (_class_vsm == NULL) {
3310       return;
3311     }
3312   }
3313 
3314   MutexLockerEx cl(SpaceManager::expand_lock(), Mutex::_no_safepoint_check_flag);
3315 
3316   // Allocate chunk for metadata objects
3317   Metachunk* new_chunk = get_initialization_chunk(NonClassType,
3318                                                   word_size,
3319                                                   vsm()->medium_chunk_bunch());
3320   assert(!DumpSharedSpaces || new_chunk != NULL, "should have enough space for both chunks");
3321   if (new_chunk != NULL) {
3322     // Add to this manager's list of chunks in use and current_chunk().
3323     vsm()->add_chunk(new_chunk, true);
3324   }
3325 
3326   // Allocate chunk for class metadata objects
3327   if (using_class_space()) {
3328     Metachunk* class_chunk = get_initialization_chunk(ClassType,
3329                                                       class_word_size,
3330                                                       class_vsm()->medium_chunk_bunch());
3331     if (class_chunk != NULL) {
3332       class_vsm()->add_chunk(class_chunk, true);
3333     }
3334   }
3335 
3336   _alloc_record_head = NULL;
3337   _alloc_record_tail = NULL;
3338 }
3339 
3340 size_t Metaspace::align_word_size_up(size_t word_size) {
3341   size_t byte_size = word_size * wordSize;
3342   return ReservedSpace::allocation_align_size_up(byte_size) / wordSize;
3343 }
3344 
3345 MetaWord* Metaspace::allocate(size_t word_size, MetadataType mdtype) {
3346   // DumpSharedSpaces doesn't use class metadata area (yet)
3347   // Also, don't use class_vsm() unless UseCompressedClassPointers is true.
3348   if (is_class_space_allocation(mdtype)) {
3349     return  class_vsm()->allocate(word_size);
3350   } else {
3351     return  vsm()->allocate(word_size);
3352   }
3353 }
3354 
3355 MetaWord* Metaspace::expand_and_allocate(size_t word_size, MetadataType mdtype) {
3356   size_t delta_bytes = MetaspaceGC::delta_capacity_until_GC(word_size * BytesPerWord);
3357   assert(delta_bytes > 0, "Must be");
3358 
3359   size_t before = 0;
3360   size_t after = 0;
3361   MetaWord* res;
3362   bool incremented;
3363 
3364   // Each thread increments the HWM at most once. Even if the thread fails to increment
3365   // the HWM, an allocation is still attempted. This is because another thread must then
3366   // have incremented the HWM and therefore the allocation might still succeed.
3367   do {
3368     incremented = MetaspaceGC::inc_capacity_until_GC(delta_bytes, &after, &before);
3369     res = allocate(word_size, mdtype);
3370   } while (!incremented && res == NULL);
3371 
3372   if (incremented) {
3373     tracer()->report_gc_threshold(before, after,
3374                                   MetaspaceGCThresholdUpdater::ExpandAndAllocate);
3375     if (PrintGCDetails && Verbose) {
3376       gclog_or_tty->print_cr("Increase capacity to GC from " SIZE_FORMAT
3377           " to " SIZE_FORMAT, before, after);
3378     }
3379   }
3380 
3381   return res;
3382 }
3383 
3384 // Space allocated in the Metaspace.  This may
3385 // be across several metadata virtual spaces.
3386 char* Metaspace::bottom() const {
3387   assert(DumpSharedSpaces, "only useful and valid for dumping shared spaces");
3388   return (char*)vsm()->current_chunk()->bottom();
3389 }
3390 
3391 size_t Metaspace::used_words_slow(MetadataType mdtype) const {
3392   if (mdtype == ClassType) {
3393     return using_class_space() ? class_vsm()->sum_used_in_chunks_in_use() : 0;
3394   } else {
3395     return vsm()->sum_used_in_chunks_in_use();  // includes overhead!
3396   }
3397 }
3398 
3399 size_t Metaspace::free_words_slow(MetadataType mdtype) const {
3400   if (mdtype == ClassType) {
3401     return using_class_space() ? class_vsm()->sum_free_in_chunks_in_use() : 0;
3402   } else {
3403     return vsm()->sum_free_in_chunks_in_use();
3404   }
3405 }
3406 
3407 // Space capacity in the Metaspace.  It includes
3408 // space in the list of chunks from which allocations
3409 // have been made. Don't include space in the global freelist and
3410 // in the space available in the dictionary which
3411 // is already counted in some chunk.
3412 size_t Metaspace::capacity_words_slow(MetadataType mdtype) const {
3413   if (mdtype == ClassType) {
3414     return using_class_space() ? class_vsm()->sum_capacity_in_chunks_in_use() : 0;
3415   } else {
3416     return vsm()->sum_capacity_in_chunks_in_use();
3417   }
3418 }
3419 
3420 size_t Metaspace::used_bytes_slow(MetadataType mdtype) const {
3421   return used_words_slow(mdtype) * BytesPerWord;
3422 }
3423 
3424 size_t Metaspace::capacity_bytes_slow(MetadataType mdtype) const {
3425   return capacity_words_slow(mdtype) * BytesPerWord;
3426 }
3427 
3428 size_t Metaspace::allocated_blocks_bytes() const {
3429   return vsm()->allocated_blocks_bytes() +
3430       (using_class_space() ? class_vsm()->allocated_blocks_bytes() : 0);
3431 }
3432 
3433 size_t Metaspace::allocated_chunks_bytes() const {
3434   return vsm()->allocated_chunks_bytes() +
3435       (using_class_space() ? class_vsm()->allocated_chunks_bytes() : 0);
3436 }
3437 
3438 void Metaspace::deallocate(MetaWord* ptr, size_t word_size, bool is_class) {
3439   assert(!SafepointSynchronize::is_at_safepoint()
3440          || Thread::current()->is_VM_thread(), "should be the VM thread");
3441 
3442   if (DumpSharedSpaces && PrintSharedSpaces) {
3443     record_deallocation(ptr, vsm()->get_raw_word_size(word_size));
3444   }
3445 
3446   MutexLockerEx ml(vsm()->lock(), Mutex::_no_safepoint_check_flag);
3447 
3448   if (word_size < TreeChunk<Metablock, FreeList<Metablock> >::min_size()) {
3449     // Dark matter.  Too small for dictionary.
3450 #ifdef ASSERT
3451     Copy::fill_to_words((HeapWord*)ptr, word_size, 0xf5f5f5f5);
3452 #endif
3453     return;
3454   }
3455   if (is_class && using_class_space()) {
3456     class_vsm()->deallocate(ptr, word_size);
3457   } else {
3458     vsm()->deallocate(ptr, word_size);
3459   }
3460 }
3461 
3462 
3463 MetaWord* Metaspace::allocate(ClassLoaderData* loader_data, size_t word_size,
3464                               bool read_only, MetaspaceObj::Type type, TRAPS) {
3465   if (HAS_PENDING_EXCEPTION) {
3466     assert(false, "Should not allocate with exception pending");
3467     return NULL;  // caller does a CHECK_NULL too
3468   }
3469 
3470   assert(loader_data != NULL, "Should never pass around a NULL loader_data. "
3471         "ClassLoaderData::the_null_class_loader_data() should have been used.");
3472 
3473   // Allocate in metaspaces without taking out a lock, because it deadlocks
3474   // with the SymbolTable_lock.  Dumping is single threaded for now.  We'll have
3475   // to revisit this for application class data sharing.
3476   if (DumpSharedSpaces) {
3477     assert(type > MetaspaceObj::UnknownType && type < MetaspaceObj::_number_of_types, "sanity");
3478     Metaspace* space = read_only ? loader_data->ro_metaspace() : loader_data->rw_metaspace();
3479     MetaWord* result = space->allocate(word_size, NonClassType);
3480     if (result == NULL) {
3481       report_out_of_shared_space(read_only ? SharedReadOnly : SharedReadWrite);
3482     }
3483     if (PrintSharedSpaces) {
3484       space->record_allocation(result, type, space->vsm()->get_raw_word_size(word_size));
3485     }
3486 
3487     // Zero initialize.
3488     Copy::fill_to_aligned_words((HeapWord*)result, word_size, 0);
3489 
3490     return result;
3491   }
3492 
3493   MetadataType mdtype = (type == MetaspaceObj::ClassType) ? ClassType : NonClassType;
3494 
3495   // Try to allocate metadata.
3496   MetaWord* result = loader_data->metaspace_non_null()->allocate(word_size, mdtype);
3497 
3498   if (result == NULL) {
3499     tracer()->report_metaspace_allocation_failure(loader_data, word_size, type, mdtype);
3500 
3501     // Allocation failed.
3502     if (is_init_completed()) {
3503       // Only start a GC if the bootstrapping has completed.
3504 
3505       // Try to clean out some memory and retry.
3506       result = Universe::heap()->collector_policy()->satisfy_failed_metadata_allocation(
3507           loader_data, word_size, mdtype);
3508     }
3509   }
3510 
3511   if (result == NULL) {
3512     report_metadata_oome(loader_data, word_size, type, mdtype, CHECK_NULL);
3513   }
3514 
3515   // Zero initialize.
3516   Copy::fill_to_aligned_words((HeapWord*)result, word_size, 0);
3517 
3518   return result;
3519 }
3520 
3521 size_t Metaspace::class_chunk_size(size_t word_size) {
3522   assert(using_class_space(), "Has to use class space");
3523   return class_vsm()->calc_chunk_size(word_size);
3524 }
3525 
3526 void Metaspace::report_metadata_oome(ClassLoaderData* loader_data, size_t word_size, MetaspaceObj::Type type, MetadataType mdtype, TRAPS) {
3527   tracer()->report_metadata_oom(loader_data, word_size, type, mdtype);
3528 
3529   // If result is still null, we are out of memory.
3530   if (Verbose && TraceMetadataChunkAllocation) {
3531     gclog_or_tty->print_cr("Metaspace allocation failed for size "
3532         SIZE_FORMAT, word_size);
3533     if (loader_data->metaspace_or_null() != NULL) {
3534       loader_data->dump(gclog_or_tty);
3535     }
3536     MetaspaceAux::dump(gclog_or_tty);
3537   }
3538 
3539   bool out_of_compressed_class_space = false;
3540   if (is_class_space_allocation(mdtype)) {
3541     Metaspace* metaspace = loader_data->metaspace_non_null();
3542     out_of_compressed_class_space =
3543       MetaspaceAux::committed_bytes(Metaspace::ClassType) +
3544       (metaspace->class_chunk_size(word_size) * BytesPerWord) >
3545       CompressedClassSpaceSize;
3546   }
3547 
3548   // -XX:+HeapDumpOnOutOfMemoryError and -XX:OnOutOfMemoryError support
3549   const char* space_string = out_of_compressed_class_space ?
3550     "Compressed class space" : "Metaspace";
3551 
3552   report_java_out_of_memory(space_string);
3553 
3554   if (JvmtiExport::should_post_resource_exhausted()) {
3555     JvmtiExport::post_resource_exhausted(
3556         JVMTI_RESOURCE_EXHAUSTED_OOM_ERROR,
3557         space_string);
3558   }
3559 
3560   if (!is_init_completed()) {
3561     vm_exit_during_initialization("OutOfMemoryError", space_string);
3562   }
3563 
3564   if (out_of_compressed_class_space) {
3565     THROW_OOP(Universe::out_of_memory_error_class_metaspace());
3566   } else {
3567     THROW_OOP(Universe::out_of_memory_error_metaspace());
3568   }
3569 }
3570 
3571 const char* Metaspace::metadata_type_name(Metaspace::MetadataType mdtype) {
3572   switch (mdtype) {
3573     case Metaspace::ClassType: return "Class";
3574     case Metaspace::NonClassType: return "Metadata";
3575     default:
3576       assert(false, err_msg("Got bad mdtype: %d", (int) mdtype));
3577       return NULL;
3578   }
3579 }
3580 
3581 void Metaspace::record_allocation(void* ptr, MetaspaceObj::Type type, size_t word_size) {
3582   assert(DumpSharedSpaces, "sanity");
3583 
3584   int byte_size = (int)word_size * HeapWordSize;
3585   AllocRecord *rec = new AllocRecord((address)ptr, type, byte_size);
3586 
3587   if (_alloc_record_head == NULL) {
3588     _alloc_record_head = _alloc_record_tail = rec;
3589   } else if (_alloc_record_tail->_ptr + _alloc_record_tail->_byte_size == (address)ptr) {
3590     _alloc_record_tail->_next = rec;
3591     _alloc_record_tail = rec;
3592   } else {
3593     // slow linear search, but this doesn't happen that often, and only when dumping
3594     for (AllocRecord *old = _alloc_record_head; old; old = old->_next) {
3595       if (old->_ptr == ptr) {
3596         assert(old->_type == MetaspaceObj::DeallocatedType, "sanity");
3597         int remain_bytes = old->_byte_size - byte_size;
3598         assert(remain_bytes >= 0, "sanity");
3599         old->_type = type;
3600 
3601         if (remain_bytes == 0) {
3602           delete(rec);
3603         } else {
3604           address remain_ptr = address(ptr) + byte_size;
3605           rec->_ptr = remain_ptr;
3606           rec->_byte_size = remain_bytes;
3607           rec->_type = MetaspaceObj::DeallocatedType;
3608           rec->_next = old->_next;
3609           old->_byte_size = byte_size;
3610           old->_next = rec;
3611         }
3612         return;
3613       }
3614     }
3615     assert(0, "reallocating a freed pointer that was not recorded");
3616   }
3617 }
3618 
3619 void Metaspace::record_deallocation(void* ptr, size_t word_size) {
3620   assert(DumpSharedSpaces, "sanity");
3621 
3622   for (AllocRecord *rec = _alloc_record_head; rec; rec = rec->_next) {
3623     if (rec->_ptr == ptr) {
3624       assert(rec->_byte_size == (int)word_size * HeapWordSize, "sanity");
3625       rec->_type = MetaspaceObj::DeallocatedType;
3626       return;
3627     }
3628   }
3629 
3630   assert(0, "deallocating a pointer that was not recorded");
3631 }
3632 
3633 void Metaspace::iterate(Metaspace::AllocRecordClosure *closure) {
3634   assert(DumpSharedSpaces, "unimplemented for !DumpSharedSpaces");
3635 
3636   address last_addr = (address)bottom();
3637 
3638   for (AllocRecord *rec = _alloc_record_head; rec; rec = rec->_next) {
3639     address ptr = rec->_ptr;
3640     if (last_addr < ptr) {
3641       closure->doit(last_addr, MetaspaceObj::UnknownType, ptr - last_addr);
3642     }
3643     closure->doit(ptr, rec->_type, rec->_byte_size);
3644     last_addr = ptr + rec->_byte_size;
3645   }
3646 
3647   address top = ((address)bottom()) + used_bytes_slow(Metaspace::NonClassType);
3648   if (last_addr < top) {
3649     closure->doit(last_addr, MetaspaceObj::UnknownType, top - last_addr);
3650   }
3651 }
3652 
3653 void Metaspace::purge(MetadataType mdtype) {
3654   get_space_list(mdtype)->purge(get_chunk_manager(mdtype));
3655 }
3656 
3657 void Metaspace::purge() {
3658   MutexLockerEx cl(SpaceManager::expand_lock(),
3659                    Mutex::_no_safepoint_check_flag);
3660   purge(NonClassType);
3661   if (using_class_space()) {
3662     purge(ClassType);
3663   }
3664 }
3665 
3666 void Metaspace::print_on(outputStream* out) const {
3667   // Print both class virtual space counts and metaspace.
3668   if (Verbose) {
3669     vsm()->print_on(out);
3670     if (using_class_space()) {
3671       class_vsm()->print_on(out);
3672     }
3673   }
3674 }
3675 
3676 bool Metaspace::contains(const void* ptr) {
3677   if (UseSharedSpaces && MetaspaceShared::is_in_shared_space(ptr)) {
3678     return true;
3679   }
3680 
3681   if (using_class_space() && get_space_list(ClassType)->contains(ptr)) {
3682      return true;
3683   }
3684 
3685   return get_space_list(NonClassType)->contains(ptr);
3686 }
3687 
3688 void Metaspace::verify() {
3689   vsm()->verify();
3690   if (using_class_space()) {
3691     class_vsm()->verify();
3692   }
3693 }
3694 
3695 void Metaspace::dump(outputStream* const out) const {
3696   out->print_cr("\nVirtual space manager: " INTPTR_FORMAT, vsm());
3697   vsm()->dump(out);
3698   if (using_class_space()) {
3699     out->print_cr("\nClass space manager: " INTPTR_FORMAT, class_vsm());
3700     class_vsm()->dump(out);
3701   }
3702 }
3703 
3704 /////////////// Unit tests ///////////////
3705 
3706 #ifndef PRODUCT
3707 
3708 class TestMetaspaceAuxTest : AllStatic {
3709  public:
3710   static void test_reserved() {
3711     size_t reserved = MetaspaceAux::reserved_bytes();
3712 
3713     assert(reserved > 0, "assert");
3714 
3715     size_t committed  = MetaspaceAux::committed_bytes();
3716     assert(committed <= reserved, "assert");
3717 
3718     size_t reserved_metadata = MetaspaceAux::reserved_bytes(Metaspace::NonClassType);
3719     assert(reserved_metadata > 0, "assert");
3720     assert(reserved_metadata <= reserved, "assert");
3721 
3722     if (UseCompressedClassPointers) {
3723       size_t reserved_class    = MetaspaceAux::reserved_bytes(Metaspace::ClassType);
3724       assert(reserved_class > 0, "assert");
3725       assert(reserved_class < reserved, "assert");
3726     }
3727   }
3728 
3729   static void test_committed() {
3730     size_t committed = MetaspaceAux::committed_bytes();
3731 
3732     assert(committed > 0, "assert");
3733 
3734     size_t reserved  = MetaspaceAux::reserved_bytes();
3735     assert(committed <= reserved, "assert");
3736 
3737     size_t committed_metadata = MetaspaceAux::committed_bytes(Metaspace::NonClassType);
3738     assert(committed_metadata > 0, "assert");
3739     assert(committed_metadata <= committed, "assert");
3740 
3741     if (UseCompressedClassPointers) {
3742       size_t committed_class    = MetaspaceAux::committed_bytes(Metaspace::ClassType);
3743       assert(committed_class > 0, "assert");
3744       assert(committed_class < committed, "assert");
3745     }
3746   }
3747 
3748   static void test_virtual_space_list_large_chunk() {
3749     VirtualSpaceList* vs_list = new VirtualSpaceList(os::vm_allocation_granularity());
3750     MutexLockerEx cl(SpaceManager::expand_lock(), Mutex::_no_safepoint_check_flag);
3751     // A size larger than VirtualSpaceSize (256k) and add one page to make it _not_ be
3752     // vm_allocation_granularity aligned on Windows.
3753     size_t large_size = (size_t)(2*256*K + (os::vm_page_size()/BytesPerWord));
3754     large_size += (os::vm_page_size()/BytesPerWord);
3755     vs_list->get_new_chunk(large_size, large_size, 0);
3756   }
3757 
3758   static void test() {
3759     test_reserved();
3760     test_committed();
3761     test_virtual_space_list_large_chunk();
3762   }
3763 };
3764 
3765 void TestMetaspaceAux_test() {
3766   TestMetaspaceAuxTest::test();
3767 }
3768 
3769 class TestVirtualSpaceNodeTest {
3770   static void chunk_up(size_t words_left, size_t& num_medium_chunks,
3771                                           size_t& num_small_chunks,
3772                                           size_t& num_specialized_chunks) {
3773     num_medium_chunks = words_left / MediumChunk;
3774     words_left = words_left % MediumChunk;
3775 
3776     num_small_chunks = words_left / SmallChunk;
3777     words_left = words_left % SmallChunk;
3778     // how many specialized chunks can we get?
3779     num_specialized_chunks = words_left / SpecializedChunk;
3780     assert(words_left % SpecializedChunk == 0, "should be nothing left");
3781   }
3782 
3783  public:
3784   static void test() {
3785     MutexLockerEx ml(SpaceManager::expand_lock(), Mutex::_no_safepoint_check_flag);
3786     const size_t vsn_test_size_words = MediumChunk  * 4;
3787     const size_t vsn_test_size_bytes = vsn_test_size_words * BytesPerWord;
3788 
3789     // The chunk sizes must be multiples of eachother, or this will fail
3790     STATIC_ASSERT(MediumChunk % SmallChunk == 0);
3791     STATIC_ASSERT(SmallChunk % SpecializedChunk == 0);
3792 
3793     { // No committed memory in VSN
3794       ChunkManager cm(SpecializedChunk, SmallChunk, MediumChunk);
3795       VirtualSpaceNode vsn(vsn_test_size_bytes);
3796       vsn.initialize();
3797       vsn.retire(&cm);
3798       assert(cm.sum_free_chunks_count() == 0, "did not commit any memory in the VSN");
3799     }
3800 
3801     { // All of VSN is committed, half is used by chunks
3802       ChunkManager cm(SpecializedChunk, SmallChunk, MediumChunk);
3803       VirtualSpaceNode vsn(vsn_test_size_bytes);
3804       vsn.initialize();
3805       vsn.expand_by(vsn_test_size_words, vsn_test_size_words);
3806       vsn.get_chunk_vs(MediumChunk);
3807       vsn.get_chunk_vs(MediumChunk);
3808       vsn.retire(&cm);
3809       assert(cm.sum_free_chunks_count() == 2, "should have been memory left for 2 medium chunks");
3810       assert(cm.sum_free_chunks() == 2*MediumChunk, "sizes should add up");
3811     }
3812 
3813     { // 4 pages of VSN is committed, some is used by chunks
3814       ChunkManager cm(SpecializedChunk, SmallChunk, MediumChunk);
3815       VirtualSpaceNode vsn(vsn_test_size_bytes);
3816       const size_t page_chunks = 4 * (size_t)os::vm_page_size() / BytesPerWord;
3817       assert(page_chunks < MediumChunk, "Test expects medium chunks to be at least 4*page_size");
3818       vsn.initialize();
3819       vsn.expand_by(page_chunks, page_chunks);
3820       vsn.get_chunk_vs(SmallChunk);
3821       vsn.get_chunk_vs(SpecializedChunk);
3822       vsn.retire(&cm);
3823 
3824       // committed - used = words left to retire
3825       const size_t words_left = page_chunks - SmallChunk - SpecializedChunk;
3826 
3827       size_t num_medium_chunks, num_small_chunks, num_spec_chunks;
3828       chunk_up(words_left, num_medium_chunks, num_small_chunks, num_spec_chunks);
3829 
3830       assert(num_medium_chunks == 0, "should not get any medium chunks");
3831       assert(cm.sum_free_chunks_count() == (num_small_chunks + num_spec_chunks), "should be space for 3 chunks");
3832       assert(cm.sum_free_chunks() == words_left, "sizes should add up");
3833     }
3834 
3835     { // Half of VSN is committed, a humongous chunk is used
3836       ChunkManager cm(SpecializedChunk, SmallChunk, MediumChunk);
3837       VirtualSpaceNode vsn(vsn_test_size_bytes);
3838       vsn.initialize();
3839       vsn.expand_by(MediumChunk * 2, MediumChunk * 2);
3840       vsn.get_chunk_vs(MediumChunk + SpecializedChunk); // Humongous chunks will be aligned up to MediumChunk + SpecializedChunk
3841       vsn.retire(&cm);
3842 
3843       const size_t words_left = MediumChunk * 2 - (MediumChunk + SpecializedChunk);
3844       size_t num_medium_chunks, num_small_chunks, num_spec_chunks;
3845       chunk_up(words_left, num_medium_chunks, num_small_chunks, num_spec_chunks);
3846 
3847       assert(num_medium_chunks == 0, "should not get any medium chunks");
3848       assert(cm.sum_free_chunks_count() == (num_small_chunks + num_spec_chunks), "should be space for 3 chunks");
3849       assert(cm.sum_free_chunks() == words_left, "sizes should add up");
3850     }
3851 
3852   }
3853 
3854 #define assert_is_available_positive(word_size) \
3855   assert(vsn.is_available(word_size), \
3856     err_msg(#word_size ": " PTR_FORMAT " bytes were not available in " \
3857             "VirtualSpaceNode [" PTR_FORMAT ", " PTR_FORMAT ")", \
3858             (uintptr_t)(word_size * BytesPerWord), vsn.bottom(), vsn.end()));
3859 
3860 #define assert_is_available_negative(word_size) \
3861   assert(!vsn.is_available(word_size), \
3862     err_msg(#word_size ": " PTR_FORMAT " bytes should not be available in " \
3863             "VirtualSpaceNode [" PTR_FORMAT ", " PTR_FORMAT ")", \
3864             (uintptr_t)(word_size * BytesPerWord), vsn.bottom(), vsn.end()));
3865 
3866   static void test_is_available_positive() {
3867     // Reserve some memory.
3868     VirtualSpaceNode vsn(os::vm_allocation_granularity());
3869     assert(vsn.initialize(), "Failed to setup VirtualSpaceNode");
3870 
3871     // Commit some memory.
3872     size_t commit_word_size = os::vm_allocation_granularity() / BytesPerWord;
3873     bool expanded = vsn.expand_by(commit_word_size, commit_word_size);
3874     assert(expanded, "Failed to commit");
3875 
3876     // Check that is_available accepts the committed size.
3877     assert_is_available_positive(commit_word_size);
3878 
3879     // Check that is_available accepts half the committed size.
3880     size_t expand_word_size = commit_word_size / 2;
3881     assert_is_available_positive(expand_word_size);
3882   }
3883 
3884   static void test_is_available_negative() {
3885     // Reserve some memory.
3886     VirtualSpaceNode vsn(os::vm_allocation_granularity());
3887     assert(vsn.initialize(), "Failed to setup VirtualSpaceNode");
3888 
3889     // Commit some memory.
3890     size_t commit_word_size = os::vm_allocation_granularity() / BytesPerWord;
3891     bool expanded = vsn.expand_by(commit_word_size, commit_word_size);
3892     assert(expanded, "Failed to commit");
3893 
3894     // Check that is_available doesn't accept a too large size.
3895     size_t two_times_commit_word_size = commit_word_size * 2;
3896     assert_is_available_negative(two_times_commit_word_size);
3897   }
3898 
3899   static void test_is_available_overflow() {
3900     // Reserve some memory.
3901     VirtualSpaceNode vsn(os::vm_allocation_granularity());
3902     assert(vsn.initialize(), "Failed to setup VirtualSpaceNode");
3903 
3904     // Commit some memory.
3905     size_t commit_word_size = os::vm_allocation_granularity() / BytesPerWord;
3906     bool expanded = vsn.expand_by(commit_word_size, commit_word_size);
3907     assert(expanded, "Failed to commit");
3908 
3909     // Calculate a size that will overflow the virtual space size.
3910     void* virtual_space_max = (void*)(uintptr_t)-1;
3911     size_t bottom_to_max = pointer_delta(virtual_space_max, vsn.bottom(), 1);
3912     size_t overflow_size = bottom_to_max + BytesPerWord;
3913     size_t overflow_word_size = overflow_size / BytesPerWord;
3914 
3915     // Check that is_available can handle the overflow.
3916     assert_is_available_negative(overflow_word_size);
3917   }
3918 
3919   static void test_is_available() {
3920     TestVirtualSpaceNodeTest::test_is_available_positive();
3921     TestVirtualSpaceNodeTest::test_is_available_negative();
3922     TestVirtualSpaceNodeTest::test_is_available_overflow();
3923   }
3924 };
3925 
3926 void TestVirtualSpaceNode_test() {
3927   TestVirtualSpaceNodeTest::test();
3928   TestVirtualSpaceNodeTest::test_is_available();
3929 }
3930 #endif