1 /*
   2  * Copyright (c) 2011, 2019, 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   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 chunk_word_size,
 535                            size_t suggested_commit_granularity);
 536 
 537   bool expand_node_by(VirtualSpaceNode* node,
 538                       size_t min_words,
 539                       size_t preferred_words);
 540 
 541   bool expand_by(size_t min_words,
 542                  size_t preferred_words);
 543 
 544   VirtualSpaceNode* current_virtual_space() {
 545     return _current_virtual_space;
 546   }
 547 
 548   bool is_class() const { return _is_class; }
 549 
 550   bool initialization_succeeded() { return _virtual_space_list != NULL; }
 551 
 552   size_t reserved_words()  { return _reserved_words; }
 553   size_t reserved_bytes()  { return reserved_words() * BytesPerWord; }
 554   size_t committed_words() { return _committed_words; }
 555   size_t committed_bytes() { return committed_words() * BytesPerWord; }
 556 
 557   void inc_reserved_words(size_t v);
 558   void dec_reserved_words(size_t v);
 559   void inc_committed_words(size_t v);
 560   void dec_committed_words(size_t v);
 561   void inc_virtual_space_count();
 562   void dec_virtual_space_count();
 563 
 564   bool contains(const void* ptr);
 565 
 566   // Unlink empty VirtualSpaceNodes and free it.
 567   void purge(ChunkManager* chunk_manager);
 568 
 569   void print_on(outputStream* st) const;
 570 
 571   class VirtualSpaceListIterator : public StackObj {
 572     VirtualSpaceNode* _virtual_spaces;
 573    public:
 574     VirtualSpaceListIterator(VirtualSpaceNode* virtual_spaces) :
 575       _virtual_spaces(virtual_spaces) {}
 576 
 577     bool repeat() {
 578       return _virtual_spaces != NULL;
 579     }
 580 
 581     VirtualSpaceNode* get_next() {
 582       VirtualSpaceNode* result = _virtual_spaces;
 583       if (_virtual_spaces != NULL) {
 584         _virtual_spaces = _virtual_spaces->next();
 585       }
 586       return result;
 587     }
 588   };
 589 };
 590 
 591 class Metadebug : AllStatic {
 592   // Debugging support for Metaspaces
 593   static int _allocation_fail_alot_count;
 594 
 595  public:
 596 
 597   static void init_allocation_fail_alot_count();
 598 #ifdef ASSERT
 599   static bool test_metadata_failure();
 600 #endif
 601 };
 602 
 603 int Metadebug::_allocation_fail_alot_count = 0;
 604 
 605 //  SpaceManager - used by Metaspace to handle allocations
 606 class SpaceManager : public CHeapObj<mtClass> {
 607   friend class Metaspace;
 608   friend class Metadebug;
 609 
 610  private:
 611 
 612   // protects allocations
 613   Mutex* const _lock;
 614 
 615   // Type of metadata allocated.
 616   Metaspace::MetadataType _mdtype;
 617 
 618   // List of chunks in use by this SpaceManager.  Allocations
 619   // are done from the current chunk.  The list is used for deallocating
 620   // chunks when the SpaceManager is freed.
 621   Metachunk* _chunks_in_use[NumberOfInUseLists];
 622   Metachunk* _current_chunk;
 623 
 624   // Number of small chunks to allocate to a manager
 625   // If class space manager, small chunks are unlimited
 626   static uint const _small_chunk_limit;
 627 
 628   // Sum of all space in allocated chunks
 629   size_t _allocated_blocks_words;
 630 
 631   // Sum of all allocated chunks
 632   size_t _allocated_chunks_words;
 633   size_t _allocated_chunks_count;
 634 
 635   // Free lists of blocks are per SpaceManager since they
 636   // are assumed to be in chunks in use by the SpaceManager
 637   // and all chunks in use by a SpaceManager are freed when
 638   // the class loader using the SpaceManager is collected.
 639   BlockFreelist _block_freelists;
 640 
 641   // protects virtualspace and chunk expansions
 642   static const char*  _expand_lock_name;
 643   static const int    _expand_lock_rank;
 644   static Mutex* const _expand_lock;
 645 
 646  private:
 647   // Accessors
 648   Metachunk* chunks_in_use(ChunkIndex index) const { return _chunks_in_use[index]; }
 649   void set_chunks_in_use(ChunkIndex index, Metachunk* v) {
 650     _chunks_in_use[index] = v;
 651   }
 652 
 653   BlockFreelist* block_freelists() const {
 654     return (BlockFreelist*) &_block_freelists;
 655   }
 656 
 657   Metaspace::MetadataType mdtype() { return _mdtype; }
 658 
 659   VirtualSpaceList* vs_list()   const { return Metaspace::get_space_list(_mdtype); }
 660   ChunkManager* chunk_manager() const { return Metaspace::get_chunk_manager(_mdtype); }
 661 
 662   Metachunk* current_chunk() const { return _current_chunk; }
 663   void set_current_chunk(Metachunk* v) {
 664     _current_chunk = v;
 665   }
 666 
 667   Metachunk* find_current_chunk(size_t word_size);
 668 
 669   // Add chunk to the list of chunks in use
 670   void add_chunk(Metachunk* v, bool make_current);
 671   void retire_current_chunk();
 672 
 673   Mutex* lock() const { return _lock; }
 674 
 675   const char* chunk_size_name(ChunkIndex index) const;
 676 
 677  protected:
 678   void initialize();
 679 
 680  public:
 681   SpaceManager(Metaspace::MetadataType mdtype,
 682                Mutex* lock);
 683   ~SpaceManager();
 684 
 685   enum ChunkMultiples {
 686     MediumChunkMultiple = 4
 687   };
 688 
 689   static size_t specialized_chunk_size(bool is_class) { return is_class ? ClassSpecializedChunk : SpecializedChunk; }
 690   static size_t small_chunk_size(bool is_class)       { return is_class ? ClassSmallChunk : SmallChunk; }
 691   static size_t medium_chunk_size(bool is_class)      { return is_class ? ClassMediumChunk : MediumChunk; }
 692 
 693   static size_t smallest_chunk_size(bool is_class)    { return specialized_chunk_size(is_class); }
 694 
 695   // Accessors
 696   bool is_class() const { return _mdtype == Metaspace::ClassType; }
 697 
 698   size_t specialized_chunk_size() const { return specialized_chunk_size(is_class()); }
 699   size_t small_chunk_size()       const { return small_chunk_size(is_class()); }
 700   size_t medium_chunk_size()      const { return medium_chunk_size(is_class()); }
 701 
 702   size_t smallest_chunk_size()    const { return smallest_chunk_size(is_class()); }
 703 
 704   size_t medium_chunk_bunch()     const { return medium_chunk_size() * MediumChunkMultiple; }
 705 
 706   size_t allocated_blocks_words() const { return _allocated_blocks_words; }
 707   size_t allocated_blocks_bytes() const { return _allocated_blocks_words * BytesPerWord; }
 708   size_t allocated_chunks_words() const { return _allocated_chunks_words; }
 709   size_t allocated_chunks_bytes() const { return _allocated_chunks_words * BytesPerWord; }
 710   size_t allocated_chunks_count() const { return _allocated_chunks_count; }
 711 
 712   bool is_humongous(size_t word_size) { return word_size > medium_chunk_size(); }
 713 
 714   static Mutex* expand_lock() { return _expand_lock; }
 715 
 716   // Increment the per Metaspace and global running sums for Metachunks
 717   // by the given size.  This is used when a Metachunk to added to
 718   // the in-use list.
 719   void inc_size_metrics(size_t words);
 720   // Increment the per Metaspace and global running sums Metablocks by the given
 721   // size.  This is used when a Metablock is allocated.
 722   void inc_used_metrics(size_t words);
 723   // Delete the portion of the running sums for this SpaceManager. That is,
 724   // the globals running sums for the Metachunks and Metablocks are
 725   // decremented for all the Metachunks in-use by this SpaceManager.
 726   void dec_total_from_size_metrics();
 727 
 728   // Adjust the initial chunk size to match one of the fixed chunk list sizes,
 729   // or return the unadjusted size if the requested size is humongous.
 730   static size_t adjust_initial_chunk_size(size_t requested, bool is_class_space);
 731   size_t adjust_initial_chunk_size(size_t requested) const;
 732 
 733   // Get the initial chunks size for this metaspace type.
 734   size_t get_initial_chunk_size(Metaspace::MetaspaceType type) const;
 735 
 736   size_t sum_capacity_in_chunks_in_use() const;
 737   size_t sum_used_in_chunks_in_use() const;
 738   size_t sum_free_in_chunks_in_use() const;
 739   size_t sum_waste_in_chunks_in_use() const;
 740   size_t sum_waste_in_chunks_in_use(ChunkIndex index ) const;
 741 
 742   size_t sum_count_in_chunks_in_use();
 743   size_t sum_count_in_chunks_in_use(ChunkIndex i);
 744 
 745   Metachunk* get_new_chunk(size_t chunk_word_size);
 746 
 747   // Block allocation and deallocation.
 748   // Allocates a block from the current chunk
 749   MetaWord* allocate(size_t word_size);
 750 
 751   // Helper for allocations
 752   MetaWord* allocate_work(size_t word_size);
 753 
 754   // Returns a block to the per manager freelist
 755   void deallocate(MetaWord* p, size_t word_size);
 756 
 757   // Based on the allocation size and a minimum chunk size,
 758   // returned chunk size (for expanding space for chunk allocation).
 759   size_t calc_chunk_size(size_t allocation_word_size);
 760 
 761   // Called when an allocation from the current chunk fails.
 762   // Gets a new chunk (may require getting a new virtual space),
 763   // and allocates from that chunk.
 764   MetaWord* grow_and_allocate(size_t word_size);
 765 
 766   // Notify memory usage to MemoryService.
 767   void track_metaspace_memory_usage();
 768 
 769   // debugging support.
 770 
 771   void dump(outputStream* const out) const;
 772   void print_on(outputStream* st) const;
 773   void locked_print_chunks_in_use_on(outputStream* st) const;
 774 
 775   void verify();
 776   void verify_chunk_size(Metachunk* chunk);
 777   NOT_PRODUCT(void mangle_freed_chunks();)
 778 #ifdef ASSERT
 779   void verify_allocated_blocks_words();
 780 #endif
 781 
 782   size_t get_raw_word_size(size_t word_size) {
 783     size_t byte_size = word_size * BytesPerWord;
 784 
 785     size_t raw_bytes_size = MAX2(byte_size, sizeof(Metablock));
 786     raw_bytes_size = align_size_up(raw_bytes_size, Metachunk::object_alignment());
 787 
 788     size_t raw_word_size = raw_bytes_size / BytesPerWord;
 789     assert(raw_word_size * BytesPerWord == raw_bytes_size, "Size problem");
 790 
 791     return raw_word_size;
 792   }
 793 };
 794 
 795 uint const SpaceManager::_small_chunk_limit = 4;
 796 
 797 const char* SpaceManager::_expand_lock_name =
 798   "SpaceManager chunk allocation lock";
 799 const int SpaceManager::_expand_lock_rank = Monitor::leaf - 1;
 800 Mutex* const SpaceManager::_expand_lock =
 801   new Mutex(SpaceManager::_expand_lock_rank,
 802             SpaceManager::_expand_lock_name,
 803             Mutex::_allow_vm_block_flag);
 804 
 805 void VirtualSpaceNode::inc_container_count() {
 806   assert_lock_strong(SpaceManager::expand_lock());
 807   _container_count++;
 808   assert(_container_count == container_count_slow(),
 809          err_msg("Inconsistency in countainer_count _container_count " SIZE_FORMAT
 810                  " container_count_slow() " SIZE_FORMAT,
 811                  _container_count, container_count_slow()));
 812 }
 813 
 814 void VirtualSpaceNode::dec_container_count() {
 815   assert_lock_strong(SpaceManager::expand_lock());
 816   _container_count--;
 817 }
 818 
 819 #ifdef ASSERT
 820 void VirtualSpaceNode::verify_container_count() {
 821   assert(_container_count == container_count_slow(),
 822     err_msg("Inconsistency in countainer_count _container_count " SIZE_FORMAT
 823             " container_count_slow() " SIZE_FORMAT, _container_count, container_count_slow()));
 824 }
 825 #endif
 826 
 827 // BlockFreelist methods
 828 
 829 BlockFreelist::BlockFreelist() : _dictionary(NULL) {}
 830 
 831 BlockFreelist::~BlockFreelist() {
 832   if (_dictionary != NULL) {
 833     if (Verbose && TraceMetadataChunkAllocation) {
 834       _dictionary->print_free_lists(gclog_or_tty);
 835     }
 836     delete _dictionary;
 837   }
 838 }
 839 
 840 void BlockFreelist::return_block(MetaWord* p, size_t word_size) {
 841   Metablock* free_chunk = ::new (p) Metablock(word_size);
 842   if (dictionary() == NULL) {
 843    _dictionary = new BlockTreeDictionary();
 844   }
 845   dictionary()->return_chunk(free_chunk);
 846 }
 847 
 848 MetaWord* BlockFreelist::get_block(size_t word_size) {
 849   if (dictionary() == NULL) {
 850     return NULL;
 851   }
 852 
 853   if (word_size < TreeChunk<Metablock, FreeList<Metablock> >::min_size()) {
 854     // Dark matter.  Too small for dictionary.
 855     return NULL;
 856   }
 857 
 858   Metablock* free_block =
 859     dictionary()->get_chunk(word_size, FreeBlockDictionary<Metablock>::atLeast);
 860   if (free_block == NULL) {
 861     return NULL;
 862   }
 863 
 864   const size_t block_size = free_block->size();
 865   if (block_size > WasteMultiplier * word_size) {
 866     return_block((MetaWord*)free_block, block_size);
 867     return NULL;
 868   }
 869 
 870   MetaWord* new_block = (MetaWord*)free_block;
 871   assert(block_size >= word_size, "Incorrect size of block from freelist");
 872   const size_t unused = block_size - word_size;
 873   if (unused >= TreeChunk<Metablock, FreeList<Metablock> >::min_size()) {
 874     return_block(new_block + word_size, unused);
 875   }
 876 
 877   return new_block;
 878 }
 879 
 880 void BlockFreelist::print_on(outputStream* st) const {
 881   if (dictionary() == NULL) {
 882     return;
 883   }
 884   dictionary()->print_free_lists(st);
 885 }
 886 
 887 // VirtualSpaceNode methods
 888 
 889 VirtualSpaceNode::~VirtualSpaceNode() {
 890   _rs.release();
 891 #ifdef ASSERT
 892   size_t word_size = sizeof(*this) / BytesPerWord;
 893   Copy::fill_to_words((HeapWord*) this, word_size, 0xf1f1f1f1);
 894 #endif
 895 }
 896 
 897 size_t VirtualSpaceNode::used_words_in_vs() const {
 898   return pointer_delta(top(), bottom(), sizeof(MetaWord));
 899 }
 900 
 901 // Space committed in the VirtualSpace
 902 size_t VirtualSpaceNode::capacity_words_in_vs() const {
 903   return pointer_delta(end(), bottom(), sizeof(MetaWord));
 904 }
 905 
 906 size_t VirtualSpaceNode::free_words_in_vs() const {
 907   return pointer_delta(end(), top(), sizeof(MetaWord));
 908 }
 909 
 910 // Allocates the chunk from the virtual space only.
 911 // This interface is also used internally for debugging.  Not all
 912 // chunks removed here are necessarily used for allocation.
 913 Metachunk* VirtualSpaceNode::take_from_committed(size_t chunk_word_size) {
 914   // Bottom of the new chunk
 915   MetaWord* chunk_limit = top();
 916   assert(chunk_limit != NULL, "Not safe to call this method");
 917 
 918   // The virtual spaces are always expanded by the
 919   // commit granularity to enforce the following condition.
 920   // Without this the is_available check will not work correctly.
 921   assert(_virtual_space.committed_size() == _virtual_space.actual_committed_size(),
 922       "The committed memory doesn't match the expanded memory.");
 923 
 924   if (!is_available(chunk_word_size)) {
 925     if (TraceMetadataChunkAllocation) {
 926       gclog_or_tty->print("VirtualSpaceNode::take_from_committed() not available %d words ", chunk_word_size);
 927       // Dump some information about the virtual space that is nearly full
 928       print_on(gclog_or_tty);
 929     }
 930     return NULL;
 931   }
 932 
 933   // Take the space  (bump top on the current virtual space).
 934   inc_top(chunk_word_size);
 935 
 936   // Initialize the chunk
 937   Metachunk* result = ::new (chunk_limit) Metachunk(chunk_word_size, this);
 938   return result;
 939 }
 940 
 941 
 942 // Expand the virtual space (commit more of the reserved space)
 943 bool VirtualSpaceNode::expand_by(size_t min_words, size_t preferred_words) {
 944   size_t min_bytes = min_words * BytesPerWord;
 945   size_t preferred_bytes = preferred_words * BytesPerWord;
 946 
 947   size_t uncommitted = virtual_space()->reserved_size() - virtual_space()->actual_committed_size();
 948 
 949   if (uncommitted < min_bytes) {
 950     return false;
 951   }
 952 
 953   size_t commit = MIN2(preferred_bytes, uncommitted);
 954   bool result = virtual_space()->expand_by(commit, false);
 955 
 956   assert(result, "Failed to commit memory");
 957 
 958   return result;
 959 }
 960 
 961 Metachunk* VirtualSpaceNode::get_chunk_vs(size_t chunk_word_size) {
 962   assert_lock_strong(SpaceManager::expand_lock());
 963   Metachunk* result = take_from_committed(chunk_word_size);
 964   if (result != NULL) {
 965     inc_container_count();
 966   }
 967   return result;
 968 }
 969 
 970 bool VirtualSpaceNode::initialize() {
 971 
 972   if (!_rs.is_reserved()) {
 973     return false;
 974   }
 975 
 976   // These are necessary restriction to make sure that the virtual space always
 977   // grows in steps of Metaspace::commit_alignment(). If both base and size are
 978   // aligned only the middle alignment of the VirtualSpace is used.
 979   assert_is_ptr_aligned(_rs.base(), Metaspace::commit_alignment());
 980   assert_is_size_aligned(_rs.size(), Metaspace::commit_alignment());
 981 
 982   // ReservedSpaces marked as special will have the entire memory
 983   // pre-committed. Setting a committed size will make sure that
 984   // committed_size and actual_committed_size agrees.
 985   size_t pre_committed_size = _rs.special() ? _rs.size() : 0;
 986 
 987   bool result = virtual_space()->initialize_with_granularity(_rs, pre_committed_size,
 988                                             Metaspace::commit_alignment());
 989   if (result) {
 990     assert(virtual_space()->committed_size() == virtual_space()->actual_committed_size(),
 991         "Checking that the pre-committed memory was registered by the VirtualSpace");
 992 
 993     set_top((MetaWord*)virtual_space()->low());
 994     set_reserved(MemRegion((HeapWord*)_rs.base(),
 995                  (HeapWord*)(_rs.base() + _rs.size())));
 996 
 997     assert(reserved()->start() == (HeapWord*) _rs.base(),
 998       err_msg("Reserved start was not set properly " PTR_FORMAT
 999         " != " PTR_FORMAT, reserved()->start(), _rs.base()));
1000     assert(reserved()->word_size() == _rs.size() / BytesPerWord,
1001       err_msg("Reserved size was not set properly " SIZE_FORMAT
1002         " != " SIZE_FORMAT, reserved()->word_size(),
1003         _rs.size() / BytesPerWord));
1004   }
1005 
1006   return result;
1007 }
1008 
1009 void VirtualSpaceNode::print_on(outputStream* st) const {
1010   size_t used = used_words_in_vs();
1011   size_t capacity = capacity_words_in_vs();
1012   VirtualSpace* vs = virtual_space();
1013   st->print_cr("   space @ " PTR_FORMAT " " SIZE_FORMAT "K, %3d%% used "
1014            "[" PTR_FORMAT ", " PTR_FORMAT ", "
1015            PTR_FORMAT ", " PTR_FORMAT ")",
1016            vs, capacity / K,
1017            capacity == 0 ? 0 : used * 100 / capacity,
1018            bottom(), top(), end(),
1019            vs->high_boundary());
1020 }
1021 
1022 #ifdef ASSERT
1023 void VirtualSpaceNode::mangle() {
1024   size_t word_size = capacity_words_in_vs();
1025   Copy::fill_to_words((HeapWord*) low(), word_size, 0xf1f1f1f1);
1026 }
1027 #endif // ASSERT
1028 
1029 // VirtualSpaceList methods
1030 // Space allocated from the VirtualSpace
1031 
1032 VirtualSpaceList::~VirtualSpaceList() {
1033   VirtualSpaceListIterator iter(virtual_space_list());
1034   while (iter.repeat()) {
1035     VirtualSpaceNode* vsl = iter.get_next();
1036     delete vsl;
1037   }
1038 }
1039 
1040 void VirtualSpaceList::inc_reserved_words(size_t v) {
1041   assert_lock_strong(SpaceManager::expand_lock());
1042   _reserved_words = _reserved_words + v;
1043 }
1044 void VirtualSpaceList::dec_reserved_words(size_t v) {
1045   assert_lock_strong(SpaceManager::expand_lock());
1046   _reserved_words = _reserved_words - v;
1047 }
1048 
1049 #define assert_committed_below_limit()                             \
1050   assert(MetaspaceAux::committed_bytes() <= MaxMetaspaceSize,      \
1051       err_msg("Too much committed memory. Committed: " SIZE_FORMAT \
1052               " limit (MaxMetaspaceSize): " SIZE_FORMAT,           \
1053           MetaspaceAux::committed_bytes(), MaxMetaspaceSize));
1054 
1055 void VirtualSpaceList::inc_committed_words(size_t v) {
1056   assert_lock_strong(SpaceManager::expand_lock());
1057   _committed_words = _committed_words + v;
1058 
1059   assert_committed_below_limit();
1060 }
1061 void VirtualSpaceList::dec_committed_words(size_t v) {
1062   assert_lock_strong(SpaceManager::expand_lock());
1063   _committed_words = _committed_words - v;
1064 
1065   assert_committed_below_limit();
1066 }
1067 
1068 void VirtualSpaceList::inc_virtual_space_count() {
1069   assert_lock_strong(SpaceManager::expand_lock());
1070   _virtual_space_count++;
1071 }
1072 void VirtualSpaceList::dec_virtual_space_count() {
1073   assert_lock_strong(SpaceManager::expand_lock());
1074   _virtual_space_count--;
1075 }
1076 
1077 void ChunkManager::remove_chunk(Metachunk* chunk) {
1078   size_t word_size = chunk->word_size();
1079   ChunkIndex index = list_index(word_size);
1080   if (index != HumongousIndex) {
1081     free_chunks(index)->remove_chunk(chunk);
1082   } else {
1083     humongous_dictionary()->remove_chunk(chunk);
1084   }
1085 
1086   // Chunk is being removed from the chunks free list.
1087   dec_free_chunks_total(chunk->word_size());
1088 }
1089 
1090 // Walk the list of VirtualSpaceNodes and delete
1091 // nodes with a 0 container_count.  Remove Metachunks in
1092 // the node from their respective freelists.
1093 void VirtualSpaceList::purge(ChunkManager* chunk_manager) {
1094   assert(SafepointSynchronize::is_at_safepoint(), "must be called at safepoint for contains to work");
1095   assert_lock_strong(SpaceManager::expand_lock());
1096   // Don't use a VirtualSpaceListIterator because this
1097   // list is being changed and a straightforward use of an iterator is not safe.
1098   VirtualSpaceNode* purged_vsl = NULL;
1099   VirtualSpaceNode* prev_vsl = virtual_space_list();
1100   VirtualSpaceNode* next_vsl = prev_vsl;
1101   while (next_vsl != NULL) {
1102     VirtualSpaceNode* vsl = next_vsl;
1103     next_vsl = vsl->next();
1104     // Don't free the current virtual space since it will likely
1105     // be needed soon.
1106     if (vsl->container_count() == 0 && vsl != current_virtual_space()) {
1107       // Unlink it from the list
1108       if (prev_vsl == vsl) {
1109         // This is the case of the current node being the first node.
1110         assert(vsl == virtual_space_list(), "Expected to be the first node");
1111         set_virtual_space_list(vsl->next());
1112       } else {
1113         prev_vsl->set_next(vsl->next());
1114       }
1115 
1116       vsl->purge(chunk_manager);
1117       dec_reserved_words(vsl->reserved_words());
1118       dec_committed_words(vsl->committed_words());
1119       dec_virtual_space_count();
1120       purged_vsl = vsl;
1121       delete vsl;
1122     } else {
1123       prev_vsl = vsl;
1124     }
1125   }
1126 #ifdef ASSERT
1127   if (purged_vsl != NULL) {
1128     // List should be stable enough to use an iterator here.
1129     VirtualSpaceListIterator iter(virtual_space_list());
1130     while (iter.repeat()) {
1131       VirtualSpaceNode* vsl = iter.get_next();
1132       assert(vsl != purged_vsl, "Purge of vsl failed");
1133     }
1134   }
1135 #endif
1136 }
1137 
1138 
1139 // This function looks at the mmap regions in the metaspace without locking.
1140 // The chunks are added with store ordering and not deleted except for at
1141 // unloading time during a safepoint.
1142 bool VirtualSpaceList::contains(const void* ptr) {
1143   // List should be stable enough to use an iterator here because removing virtual
1144   // space nodes is only allowed at a safepoint.
1145   VirtualSpaceListIterator iter(virtual_space_list());
1146   while (iter.repeat()) {
1147     VirtualSpaceNode* vsn = iter.get_next();
1148     if (vsn->contains(ptr)) {
1149       return true;
1150     }
1151   }
1152   return false;
1153 }
1154 
1155 void VirtualSpaceList::retire_current_virtual_space() {
1156   assert_lock_strong(SpaceManager::expand_lock());
1157 
1158   VirtualSpaceNode* vsn = current_virtual_space();
1159 
1160   ChunkManager* cm = is_class() ? Metaspace::chunk_manager_class() :
1161                                   Metaspace::chunk_manager_metadata();
1162 
1163   vsn->retire(cm);
1164 }
1165 
1166 void VirtualSpaceNode::retire(ChunkManager* chunk_manager) {
1167   for (int i = (int)MediumIndex; i >= (int)ZeroIndex; --i) {
1168     ChunkIndex index = (ChunkIndex)i;
1169     size_t chunk_size = chunk_manager->free_chunks(index)->size();
1170 
1171     while (free_words_in_vs() >= chunk_size) {
1172       DEBUG_ONLY(verify_container_count();)
1173       Metachunk* chunk = get_chunk_vs(chunk_size);
1174       assert(chunk != NULL, "allocation should have been successful");
1175 
1176       chunk_manager->return_chunks(index, chunk);
1177       chunk_manager->inc_free_chunks_total(chunk_size);
1178       DEBUG_ONLY(verify_container_count();)
1179     }
1180   }
1181   assert(free_words_in_vs() == 0, "should be empty now");
1182 }
1183 
1184 VirtualSpaceList::VirtualSpaceList(size_t word_size) :
1185                                    _is_class(false),
1186                                    _virtual_space_list(NULL),
1187                                    _current_virtual_space(NULL),
1188                                    _reserved_words(0),
1189                                    _committed_words(0),
1190                                    _virtual_space_count(0) {
1191   MutexLockerEx cl(SpaceManager::expand_lock(),
1192                    Mutex::_no_safepoint_check_flag);
1193   create_new_virtual_space(word_size);
1194 }
1195 
1196 VirtualSpaceList::VirtualSpaceList(ReservedSpace rs) :
1197                                    _is_class(true),
1198                                    _virtual_space_list(NULL),
1199                                    _current_virtual_space(NULL),
1200                                    _reserved_words(0),
1201                                    _committed_words(0),
1202                                    _virtual_space_count(0) {
1203   MutexLockerEx cl(SpaceManager::expand_lock(),
1204                    Mutex::_no_safepoint_check_flag);
1205   VirtualSpaceNode* class_entry = new VirtualSpaceNode(rs);
1206   bool succeeded = class_entry->initialize();
1207   if (succeeded) {
1208     link_vs(class_entry);
1209   }
1210 }
1211 
1212 size_t VirtualSpaceList::free_bytes() {
1213   return current_virtual_space()->free_words_in_vs() * BytesPerWord;
1214 }
1215 
1216 // Allocate another meta virtual space and add it to the list.
1217 bool VirtualSpaceList::create_new_virtual_space(size_t vs_word_size) {
1218   assert_lock_strong(SpaceManager::expand_lock());
1219 
1220   if (is_class()) {
1221     assert(false, "We currently don't support more than one VirtualSpace for"
1222                   " the compressed class space. The initialization of the"
1223                   " CCS uses another code path and should not hit this path.");
1224     return false;
1225   }
1226 
1227   if (vs_word_size == 0) {
1228     assert(false, "vs_word_size should always be at least _reserve_alignment large.");
1229     return false;
1230   }
1231 
1232   // Reserve the space
1233   size_t vs_byte_size = vs_word_size * BytesPerWord;
1234   assert_is_size_aligned(vs_byte_size, Metaspace::reserve_alignment());
1235 
1236   // Allocate the meta virtual space and initialize it.
1237   VirtualSpaceNode* new_entry = new VirtualSpaceNode(vs_byte_size);
1238   if (!new_entry->initialize()) {
1239     delete new_entry;
1240     return false;
1241   } else {
1242     assert(new_entry->reserved_words() == vs_word_size,
1243         "Reserved memory size differs from requested memory size");
1244     // ensure lock-free iteration sees fully initialized node
1245     OrderAccess::storestore();
1246     link_vs(new_entry);
1247     return true;
1248   }
1249 }
1250 
1251 void VirtualSpaceList::link_vs(VirtualSpaceNode* new_entry) {
1252   if (virtual_space_list() == NULL) {
1253       set_virtual_space_list(new_entry);
1254   } else {
1255     current_virtual_space()->set_next(new_entry);
1256   }
1257   set_current_virtual_space(new_entry);
1258   inc_reserved_words(new_entry->reserved_words());
1259   inc_committed_words(new_entry->committed_words());
1260   inc_virtual_space_count();
1261 #ifdef ASSERT
1262   new_entry->mangle();
1263 #endif
1264   if (TraceMetavirtualspaceAllocation && Verbose) {
1265     VirtualSpaceNode* vsl = current_virtual_space();
1266     vsl->print_on(gclog_or_tty);
1267   }
1268 }
1269 
1270 bool VirtualSpaceList::expand_node_by(VirtualSpaceNode* node,
1271                                       size_t min_words,
1272                                       size_t preferred_words) {
1273   size_t before = node->committed_words();
1274 
1275   bool result = node->expand_by(min_words, preferred_words);
1276 
1277   size_t after = node->committed_words();
1278 
1279   // after and before can be the same if the memory was pre-committed.
1280   assert(after >= before, "Inconsistency");
1281   inc_committed_words(after - before);
1282 
1283   return result;
1284 }
1285 
1286 bool VirtualSpaceList::expand_by(size_t min_words, size_t preferred_words) {
1287   assert_is_size_aligned(min_words,       Metaspace::commit_alignment_words());
1288   assert_is_size_aligned(preferred_words, Metaspace::commit_alignment_words());
1289   assert(min_words <= preferred_words, "Invalid arguments");
1290 
1291   if (!MetaspaceGC::can_expand(min_words, this->is_class())) {
1292     return  false;
1293   }
1294 
1295   size_t allowed_expansion_words = MetaspaceGC::allowed_expansion();
1296   if (allowed_expansion_words < min_words) {
1297     return false;
1298   }
1299 
1300   size_t max_expansion_words = MIN2(preferred_words, allowed_expansion_words);
1301 
1302   // Commit more memory from the the current virtual space.
1303   bool vs_expanded = expand_node_by(current_virtual_space(),
1304                                     min_words,
1305                                     max_expansion_words);
1306   if (vs_expanded) {
1307     return true;
1308   }
1309   retire_current_virtual_space();
1310 
1311   // Get another virtual space.
1312   size_t grow_vs_words = MAX2((size_t)VirtualSpaceSize, preferred_words);
1313   grow_vs_words = align_size_up(grow_vs_words, Metaspace::reserve_alignment_words());
1314 
1315   if (create_new_virtual_space(grow_vs_words)) {
1316     if (current_virtual_space()->is_pre_committed()) {
1317       // The memory was pre-committed, so we are done here.
1318       assert(min_words <= current_virtual_space()->committed_words(),
1319           "The new VirtualSpace was pre-committed, so it"
1320           "should be large enough to fit the alloc request.");
1321       return true;
1322     }
1323 
1324     return expand_node_by(current_virtual_space(),
1325                           min_words,
1326                           max_expansion_words);
1327   }
1328 
1329   return false;
1330 }
1331 
1332 Metachunk* VirtualSpaceList::get_new_chunk(size_t chunk_word_size, size_t suggested_commit_granularity) {
1333 
1334   // Allocate a chunk out of the current virtual space.
1335   Metachunk* next = current_virtual_space()->get_chunk_vs(chunk_word_size);
1336 
1337   if (next != NULL) {
1338     return next;
1339   }
1340 
1341   // The expand amount is currently only determined by the requested sizes
1342   // and not how much committed memory is left in the current virtual space.
1343 
1344   size_t min_word_size       = align_size_up(chunk_word_size,              Metaspace::commit_alignment_words());
1345   size_t preferred_word_size = align_size_up(suggested_commit_granularity, Metaspace::commit_alignment_words());
1346   if (min_word_size >= preferred_word_size) {
1347     // Can happen when humongous chunks are allocated.
1348     preferred_word_size = min_word_size;
1349   }
1350 
1351   bool expanded = expand_by(min_word_size, preferred_word_size);
1352   if (expanded) {
1353     next = current_virtual_space()->get_chunk_vs(chunk_word_size);
1354     assert(next != NULL, "The allocation was expected to succeed after the expansion");
1355   }
1356 
1357    return next;
1358 }
1359 
1360 void VirtualSpaceList::print_on(outputStream* st) const {
1361   if (TraceMetadataChunkAllocation && Verbose) {
1362     VirtualSpaceListIterator iter(virtual_space_list());
1363     while (iter.repeat()) {
1364       VirtualSpaceNode* node = iter.get_next();
1365       node->print_on(st);
1366     }
1367   }
1368 }
1369 
1370 // MetaspaceGC methods
1371 
1372 // VM_CollectForMetadataAllocation is the vm operation used to GC.
1373 // Within the VM operation after the GC the attempt to allocate the metadata
1374 // should succeed.  If the GC did not free enough space for the metaspace
1375 // allocation, the HWM is increased so that another virtualspace will be
1376 // allocated for the metadata.  With perm gen the increase in the perm
1377 // gen had bounds, MinMetaspaceExpansion and MaxMetaspaceExpansion.  The
1378 // metaspace policy uses those as the small and large steps for the HWM.
1379 //
1380 // After the GC the compute_new_size() for MetaspaceGC is called to
1381 // resize the capacity of the metaspaces.  The current implementation
1382 // is based on the flags MinMetaspaceFreeRatio and MaxMetaspaceFreeRatio used
1383 // to resize the Java heap by some GC's.  New flags can be implemented
1384 // if really needed.  MinMetaspaceFreeRatio is used to calculate how much
1385 // free space is desirable in the metaspace capacity to decide how much
1386 // to increase the HWM.  MaxMetaspaceFreeRatio is used to decide how much
1387 // free space is desirable in the metaspace capacity before decreasing
1388 // the HWM.
1389 
1390 // Calculate the amount to increase the high water mark (HWM).
1391 // Increase by a minimum amount (MinMetaspaceExpansion) so that
1392 // another expansion is not requested too soon.  If that is not
1393 // enough to satisfy the allocation, increase by MaxMetaspaceExpansion.
1394 // If that is still not enough, expand by the size of the allocation
1395 // plus some.
1396 size_t MetaspaceGC::delta_capacity_until_GC(size_t bytes) {
1397   size_t min_delta = MinMetaspaceExpansion;
1398   size_t max_delta = MaxMetaspaceExpansion;
1399   size_t delta = align_size_up(bytes, Metaspace::commit_alignment());
1400 
1401   if (delta <= min_delta) {
1402     delta = min_delta;
1403   } else if (delta <= max_delta) {
1404     // Don't want to hit the high water mark on the next
1405     // allocation so make the delta greater than just enough
1406     // for this allocation.
1407     delta = max_delta;
1408   } else {
1409     // This allocation is large but the next ones are probably not
1410     // so increase by the minimum.
1411     delta = delta + min_delta;
1412   }
1413 
1414   assert_is_size_aligned(delta, Metaspace::commit_alignment());
1415 
1416   return delta;
1417 }
1418 
1419 size_t MetaspaceGC::capacity_until_GC() {
1420   size_t value = (size_t)OrderAccess::load_ptr_acquire(&_capacity_until_GC);
1421   assert(value >= MetaspaceSize, "Not initialied properly?");
1422   return value;
1423 }
1424 
1425 // Try to increase the _capacity_until_GC limit counter by v bytes.
1426 // Returns true if it succeeded. It may fail if either another thread
1427 // concurrently increased the limit or the new limit would be larger
1428 // than MaxMetaspaceSize.
1429 // On success, optionally returns new and old metaspace capacity in
1430 // new_cap_until_GC and old_cap_until_GC respectively.
1431 // On error, optionally sets can_retry to indicate whether if there is
1432 // actually enough space remaining to satisfy the request.
1433 bool MetaspaceGC::inc_capacity_until_GC(size_t v, size_t* new_cap_until_GC, size_t* old_cap_until_GC, bool* can_retry) {
1434   assert_is_size_aligned(v, Metaspace::commit_alignment());
1435 
1436   size_t capacity_until_GC = (size_t) _capacity_until_GC;
1437   size_t new_value = capacity_until_GC + v;
1438 
1439   if (new_value < capacity_until_GC) {
1440     // The addition wrapped around, set new_value to aligned max value.
1441     new_value = align_size_down(max_uintx, Metaspace::commit_alignment());
1442   }
1443 
1444   if (new_value > MaxMetaspaceSize) {
1445     if (can_retry != NULL) {
1446       *can_retry = false;
1447     }
1448     return false;
1449   }
1450 
1451   if (can_retry != NULL) {
1452     *can_retry = true;
1453   }
1454 
1455   intptr_t expected = (intptr_t) capacity_until_GC;
1456   intptr_t actual = Atomic::cmpxchg_ptr((intptr_t) new_value, &_capacity_until_GC, expected);
1457 
1458   if (expected != actual) {
1459     return false;
1460   }
1461 
1462   if (new_cap_until_GC != NULL) {
1463     *new_cap_until_GC = new_value;
1464   }
1465   if (old_cap_until_GC != NULL) {
1466     *old_cap_until_GC = capacity_until_GC;
1467   }
1468   return true;
1469 }
1470 
1471 size_t MetaspaceGC::dec_capacity_until_GC(size_t v) {
1472   assert_is_size_aligned(v, Metaspace::commit_alignment());
1473 
1474   return (size_t)Atomic::add_ptr(-(intptr_t)v, &_capacity_until_GC);
1475 }
1476 
1477 void MetaspaceGC::initialize() {
1478   // Set the high-water mark to MaxMetapaceSize during VM initializaton since
1479   // we can't do a GC during initialization.
1480   _capacity_until_GC = MaxMetaspaceSize;
1481 }
1482 
1483 void MetaspaceGC::post_initialize() {
1484   // Reset the high-water mark once the VM initialization is done.
1485   _capacity_until_GC = MAX2(MetaspaceAux::committed_bytes(), MetaspaceSize);
1486 }
1487 
1488 bool MetaspaceGC::can_expand(size_t word_size, bool is_class) {
1489   // Check if the compressed class space is full.
1490   if (is_class && Metaspace::using_class_space()) {
1491     size_t class_committed = MetaspaceAux::committed_bytes(Metaspace::ClassType);
1492     if (class_committed + word_size * BytesPerWord > CompressedClassSpaceSize) {
1493       return false;
1494     }
1495   }
1496 
1497   // Check if the user has imposed a limit on the metaspace memory.
1498   size_t committed_bytes = MetaspaceAux::committed_bytes();
1499   if (committed_bytes + word_size * BytesPerWord > MaxMetaspaceSize) {
1500     return false;
1501   }
1502 
1503   return true;
1504 }
1505 
1506 size_t MetaspaceGC::allowed_expansion() {
1507   size_t committed_bytes = MetaspaceAux::committed_bytes();
1508   size_t capacity_until_gc = capacity_until_GC();
1509 
1510   assert(capacity_until_gc >= committed_bytes,
1511         err_msg("capacity_until_gc: " SIZE_FORMAT " < committed_bytes: " SIZE_FORMAT,
1512                 capacity_until_gc, committed_bytes));
1513 
1514   size_t left_until_max  = MaxMetaspaceSize - committed_bytes;
1515   size_t left_until_GC = capacity_until_gc - committed_bytes;
1516   size_t left_to_commit = MIN2(left_until_GC, left_until_max);
1517 
1518   return left_to_commit / BytesPerWord;
1519 }
1520 
1521 void MetaspaceGC::compute_new_size() {
1522   assert(_shrink_factor <= 100, "invalid shrink factor");
1523   uint current_shrink_factor = _shrink_factor;
1524   _shrink_factor = 0;
1525 
1526   // Using committed_bytes() for used_after_gc is an overestimation, since the
1527   // chunk free lists are included in committed_bytes() and the memory in an
1528   // un-fragmented chunk free list is available for future allocations.
1529   // However, if the chunk free lists becomes fragmented, then the memory may
1530   // not be available for future allocations and the memory is therefore "in use".
1531   // Including the chunk free lists in the definition of "in use" is therefore
1532   // necessary. Not including the chunk free lists can cause capacity_until_GC to
1533   // shrink below committed_bytes() and this has caused serious bugs in the past.
1534   const size_t used_after_gc = MetaspaceAux::committed_bytes();
1535   const size_t capacity_until_GC = MetaspaceGC::capacity_until_GC();
1536 
1537   const double minimum_free_percentage = MinMetaspaceFreeRatio / 100.0;
1538   const double maximum_used_percentage = 1.0 - minimum_free_percentage;
1539 
1540   const double min_tmp = used_after_gc / maximum_used_percentage;
1541   size_t minimum_desired_capacity =
1542     (size_t)MIN2(min_tmp, double(MaxMetaspaceSize));
1543   // Don't shrink less than the initial generation size
1544   minimum_desired_capacity = MAX2(minimum_desired_capacity,
1545                                   MetaspaceSize);
1546 
1547   if (PrintGCDetails && Verbose) {
1548     gclog_or_tty->print_cr("\nMetaspaceGC::compute_new_size: ");
1549     gclog_or_tty->print_cr("  "
1550                   "  minimum_free_percentage: %6.2f"
1551                   "  maximum_used_percentage: %6.2f",
1552                   minimum_free_percentage,
1553                   maximum_used_percentage);
1554     gclog_or_tty->print_cr("  "
1555                   "   used_after_gc       : %6.1fKB",
1556                   used_after_gc / (double) K);
1557   }
1558 
1559 
1560   size_t shrink_bytes = 0;
1561   if (capacity_until_GC < minimum_desired_capacity) {
1562     // If we have less capacity below the metaspace HWM, then
1563     // increment the HWM.
1564     size_t expand_bytes = minimum_desired_capacity - capacity_until_GC;
1565     expand_bytes = align_size_up(expand_bytes, Metaspace::commit_alignment());
1566     // Don't expand unless it's significant
1567     if (expand_bytes >= MinMetaspaceExpansion) {
1568       size_t new_capacity_until_GC = 0;
1569       bool succeeded = MetaspaceGC::inc_capacity_until_GC(expand_bytes, &new_capacity_until_GC);
1570       assert(succeeded, "Should always succesfully increment HWM when at safepoint");
1571 
1572       Metaspace::tracer()->report_gc_threshold(capacity_until_GC,
1573                                                new_capacity_until_GC,
1574                                                MetaspaceGCThresholdUpdater::ComputeNewSize);
1575       if (PrintGCDetails && Verbose) {
1576         gclog_or_tty->print_cr("    expanding:"
1577                       "  minimum_desired_capacity: %6.1fKB"
1578                       "  expand_bytes: %6.1fKB"
1579                       "  MinMetaspaceExpansion: %6.1fKB"
1580                       "  new metaspace HWM:  %6.1fKB",
1581                       minimum_desired_capacity / (double) K,
1582                       expand_bytes / (double) K,
1583                       MinMetaspaceExpansion / (double) K,
1584                       new_capacity_until_GC / (double) K);
1585       }
1586     }
1587     return;
1588   }
1589 
1590   // No expansion, now see if we want to shrink
1591   // We would never want to shrink more than this
1592   size_t max_shrink_bytes = capacity_until_GC - minimum_desired_capacity;
1593   assert(max_shrink_bytes >= 0, err_msg("max_shrink_bytes " SIZE_FORMAT,
1594     max_shrink_bytes));
1595 
1596   // Should shrinking be considered?
1597   if (MaxMetaspaceFreeRatio < 100) {
1598     const double maximum_free_percentage = MaxMetaspaceFreeRatio / 100.0;
1599     const double minimum_used_percentage = 1.0 - maximum_free_percentage;
1600     const double max_tmp = used_after_gc / minimum_used_percentage;
1601     size_t maximum_desired_capacity = (size_t)MIN2(max_tmp, double(MaxMetaspaceSize));
1602     maximum_desired_capacity = MAX2(maximum_desired_capacity,
1603                                     MetaspaceSize);
1604     if (PrintGCDetails && Verbose) {
1605       gclog_or_tty->print_cr("  "
1606                              "  maximum_free_percentage: %6.2f"
1607                              "  minimum_used_percentage: %6.2f",
1608                              maximum_free_percentage,
1609                              minimum_used_percentage);
1610       gclog_or_tty->print_cr("  "
1611                              "  minimum_desired_capacity: %6.1fKB"
1612                              "  maximum_desired_capacity: %6.1fKB",
1613                              minimum_desired_capacity / (double) K,
1614                              maximum_desired_capacity / (double) K);
1615     }
1616 
1617     assert(minimum_desired_capacity <= maximum_desired_capacity,
1618            "sanity check");
1619 
1620     if (capacity_until_GC > maximum_desired_capacity) {
1621       // Capacity too large, compute shrinking size
1622       shrink_bytes = capacity_until_GC - maximum_desired_capacity;
1623       // We don't want shrink all the way back to initSize if people call
1624       // System.gc(), because some programs do that between "phases" and then
1625       // we'd just have to grow the heap up again for the next phase.  So we
1626       // damp the shrinking: 0% on the first call, 10% on the second call, 40%
1627       // on the third call, and 100% by the fourth call.  But if we recompute
1628       // size without shrinking, it goes back to 0%.
1629       shrink_bytes = shrink_bytes / 100 * current_shrink_factor;
1630 
1631       shrink_bytes = align_size_down(shrink_bytes, Metaspace::commit_alignment());
1632 
1633       assert(shrink_bytes <= max_shrink_bytes,
1634         err_msg("invalid shrink size " SIZE_FORMAT " not <= " SIZE_FORMAT,
1635           shrink_bytes, max_shrink_bytes));
1636       if (current_shrink_factor == 0) {
1637         _shrink_factor = 10;
1638       } else {
1639         _shrink_factor = MIN2(current_shrink_factor * 4, (uint) 100);
1640       }
1641       if (PrintGCDetails && Verbose) {
1642         gclog_or_tty->print_cr("  "
1643                       "  shrinking:"
1644                       "  initSize: %.1fK"
1645                       "  maximum_desired_capacity: %.1fK",
1646                       MetaspaceSize / (double) K,
1647                       maximum_desired_capacity / (double) K);
1648         gclog_or_tty->print_cr("  "
1649                       "  shrink_bytes: %.1fK"
1650                       "  current_shrink_factor: %d"
1651                       "  new shrink factor: %d"
1652                       "  MinMetaspaceExpansion: %.1fK",
1653                       shrink_bytes / (double) K,
1654                       current_shrink_factor,
1655                       _shrink_factor,
1656                       MinMetaspaceExpansion / (double) K);
1657       }
1658     }
1659   }
1660 
1661   // Don't shrink unless it's significant
1662   if (shrink_bytes >= MinMetaspaceExpansion &&
1663       ((capacity_until_GC - shrink_bytes) >= MetaspaceSize)) {
1664     size_t new_capacity_until_GC = MetaspaceGC::dec_capacity_until_GC(shrink_bytes);
1665     Metaspace::tracer()->report_gc_threshold(capacity_until_GC,
1666                                              new_capacity_until_GC,
1667                                              MetaspaceGCThresholdUpdater::ComputeNewSize);
1668   }
1669 }
1670 
1671 // Metadebug methods
1672 
1673 void Metadebug::init_allocation_fail_alot_count() {
1674   if (MetadataAllocationFailALot) {
1675     _allocation_fail_alot_count =
1676       1+(long)((double)MetadataAllocationFailALotInterval*os::random()/(max_jint+1.0));
1677   }
1678 }
1679 
1680 #ifdef ASSERT
1681 bool Metadebug::test_metadata_failure() {
1682   if (MetadataAllocationFailALot &&
1683       Threads::is_vm_complete()) {
1684     if (_allocation_fail_alot_count > 0) {
1685       _allocation_fail_alot_count--;
1686     } else {
1687       if (TraceMetadataChunkAllocation && Verbose) {
1688         gclog_or_tty->print_cr("Metadata allocation failing for "
1689                                "MetadataAllocationFailALot");
1690       }
1691       init_allocation_fail_alot_count();
1692       return true;
1693     }
1694   }
1695   return false;
1696 }
1697 #endif
1698 
1699 // ChunkManager methods
1700 
1701 size_t ChunkManager::free_chunks_total_words() {
1702   return _free_chunks_total;
1703 }
1704 
1705 size_t ChunkManager::free_chunks_total_bytes() {
1706   return free_chunks_total_words() * BytesPerWord;
1707 }
1708 
1709 size_t ChunkManager::free_chunks_count() {
1710 #ifdef ASSERT
1711   if (!UseConcMarkSweepGC && !SpaceManager::expand_lock()->is_locked()) {
1712     MutexLockerEx cl(SpaceManager::expand_lock(),
1713                      Mutex::_no_safepoint_check_flag);
1714     // This lock is only needed in debug because the verification
1715     // of the _free_chunks_totals walks the list of free chunks
1716     slow_locked_verify_free_chunks_count();
1717   }
1718 #endif
1719   return _free_chunks_count;
1720 }
1721 
1722 void ChunkManager::locked_verify_free_chunks_total() {
1723   assert_lock_strong(SpaceManager::expand_lock());
1724   assert(sum_free_chunks() == _free_chunks_total,
1725     err_msg("_free_chunks_total " SIZE_FORMAT " is not the"
1726            " same as sum " SIZE_FORMAT, _free_chunks_total,
1727            sum_free_chunks()));
1728 }
1729 
1730 void ChunkManager::verify_free_chunks_total() {
1731   MutexLockerEx cl(SpaceManager::expand_lock(),
1732                      Mutex::_no_safepoint_check_flag);
1733   locked_verify_free_chunks_total();
1734 }
1735 
1736 void ChunkManager::locked_verify_free_chunks_count() {
1737   assert_lock_strong(SpaceManager::expand_lock());
1738   assert(sum_free_chunks_count() == _free_chunks_count,
1739     err_msg("_free_chunks_count " SIZE_FORMAT " is not the"
1740            " same as sum " SIZE_FORMAT, _free_chunks_count,
1741            sum_free_chunks_count()));
1742 }
1743 
1744 void ChunkManager::verify_free_chunks_count() {
1745 #ifdef ASSERT
1746   MutexLockerEx cl(SpaceManager::expand_lock(),
1747                      Mutex::_no_safepoint_check_flag);
1748   locked_verify_free_chunks_count();
1749 #endif
1750 }
1751 
1752 void ChunkManager::verify() {
1753   MutexLockerEx cl(SpaceManager::expand_lock(),
1754                      Mutex::_no_safepoint_check_flag);
1755   locked_verify();
1756 }
1757 
1758 void ChunkManager::locked_verify() {
1759   locked_verify_free_chunks_count();
1760   locked_verify_free_chunks_total();
1761 }
1762 
1763 void ChunkManager::locked_print_free_chunks(outputStream* st) {
1764   assert_lock_strong(SpaceManager::expand_lock());
1765   st->print_cr("Free chunk total " SIZE_FORMAT "  count " SIZE_FORMAT,
1766                 _free_chunks_total, _free_chunks_count);
1767 }
1768 
1769 void ChunkManager::locked_print_sum_free_chunks(outputStream* st) {
1770   assert_lock_strong(SpaceManager::expand_lock());
1771   st->print_cr("Sum free chunk total " SIZE_FORMAT "  count " SIZE_FORMAT,
1772                 sum_free_chunks(), sum_free_chunks_count());
1773 }
1774 
1775 ChunkList* ChunkManager::free_chunks(ChunkIndex index) {
1776   assert(index == SpecializedIndex || index == SmallIndex || index == MediumIndex,
1777          err_msg("Bad index: %d", (int)index));
1778 
1779   return &_free_chunks[index];
1780 }
1781 
1782 // These methods that sum the free chunk lists are used in printing
1783 // methods that are used in product builds.
1784 size_t ChunkManager::sum_free_chunks() {
1785   assert_lock_strong(SpaceManager::expand_lock());
1786   size_t result = 0;
1787   for (ChunkIndex i = ZeroIndex; i < NumberOfFreeLists; i = next_chunk_index(i)) {
1788     ChunkList* list = free_chunks(i);
1789 
1790     if (list == NULL) {
1791       continue;
1792     }
1793 
1794     result = result + list->count() * list->size();
1795   }
1796   result = result + humongous_dictionary()->total_size();
1797   return result;
1798 }
1799 
1800 size_t ChunkManager::sum_free_chunks_count() {
1801   assert_lock_strong(SpaceManager::expand_lock());
1802   size_t count = 0;
1803   for (ChunkIndex i = ZeroIndex; i < NumberOfFreeLists; i = next_chunk_index(i)) {
1804     ChunkList* list = free_chunks(i);
1805     if (list == NULL) {
1806       continue;
1807     }
1808     count = count + list->count();
1809   }
1810   count = count + humongous_dictionary()->total_free_blocks();
1811   return count;
1812 }
1813 
1814 ChunkList* ChunkManager::find_free_chunks_list(size_t word_size) {
1815   ChunkIndex index = list_index(word_size);
1816   assert(index < HumongousIndex, "No humongous list");
1817   return free_chunks(index);
1818 }
1819 
1820 Metachunk* ChunkManager::free_chunks_get(size_t word_size) {
1821   assert_lock_strong(SpaceManager::expand_lock());
1822 
1823   slow_locked_verify();
1824 
1825   Metachunk* chunk = NULL;
1826   if (list_index(word_size) != HumongousIndex) {
1827     ChunkList* free_list = find_free_chunks_list(word_size);
1828     assert(free_list != NULL, "Sanity check");
1829 
1830     chunk = free_list->head();
1831 
1832     if (chunk == NULL) {
1833       return NULL;
1834     }
1835 
1836     // Remove the chunk as the head of the list.
1837     free_list->remove_chunk(chunk);
1838 
1839     if (TraceMetadataChunkAllocation && Verbose) {
1840       gclog_or_tty->print_cr("ChunkManager::free_chunks_get: free_list "
1841                              PTR_FORMAT " head " PTR_FORMAT " size " SIZE_FORMAT,
1842                              free_list, chunk, chunk->word_size());
1843     }
1844   } else {
1845     chunk = humongous_dictionary()->get_chunk(
1846       word_size,
1847       FreeBlockDictionary<Metachunk>::atLeast);
1848 
1849     if (chunk == NULL) {
1850       return NULL;
1851     }
1852 
1853     if (TraceMetadataHumongousAllocation) {
1854       size_t waste = chunk->word_size() - word_size;
1855       gclog_or_tty->print_cr("Free list allocate humongous chunk size "
1856                              SIZE_FORMAT " for requested size " SIZE_FORMAT
1857                              " waste " SIZE_FORMAT,
1858                              chunk->word_size(), word_size, waste);
1859     }
1860   }
1861 
1862   // Chunk is being removed from the chunks free list.
1863   dec_free_chunks_total(chunk->word_size());
1864 
1865   // Remove it from the links to this freelist
1866   chunk->set_next(NULL);
1867   chunk->set_prev(NULL);
1868 #ifdef ASSERT
1869   // Chunk is no longer on any freelist. Setting to false make container_count_slow()
1870   // work.
1871   chunk->set_is_tagged_free(false);
1872 #endif
1873   chunk->container()->inc_container_count();
1874 
1875   slow_locked_verify();
1876   return chunk;
1877 }
1878 
1879 Metachunk* ChunkManager::chunk_freelist_allocate(size_t word_size) {
1880   assert_lock_strong(SpaceManager::expand_lock());
1881   slow_locked_verify();
1882 
1883   // Take from the beginning of the list
1884   Metachunk* chunk = free_chunks_get(word_size);
1885   if (chunk == NULL) {
1886     return NULL;
1887   }
1888 
1889   assert((word_size <= chunk->word_size()) ||
1890          (list_index(chunk->word_size()) == HumongousIndex),
1891          "Non-humongous variable sized chunk");
1892   if (TraceMetadataChunkAllocation) {
1893     size_t list_count;
1894     if (list_index(word_size) < HumongousIndex) {
1895       ChunkList* list = find_free_chunks_list(word_size);
1896       list_count = list->count();
1897     } else {
1898       list_count = humongous_dictionary()->total_count();
1899     }
1900     gclog_or_tty->print("ChunkManager::chunk_freelist_allocate: " PTR_FORMAT " chunk "
1901                         PTR_FORMAT "  size " SIZE_FORMAT " count " SIZE_FORMAT " ",
1902                         this, chunk, chunk->word_size(), list_count);
1903     locked_print_free_chunks(gclog_or_tty);
1904   }
1905 
1906   return chunk;
1907 }
1908 
1909 void ChunkManager::print_on(outputStream* out) const {
1910   if (PrintFLSStatistics != 0) {
1911     const_cast<ChunkManager *>(this)->humongous_dictionary()->report_statistics();
1912   }
1913 }
1914 
1915 // SpaceManager methods
1916 
1917 size_t SpaceManager::adjust_initial_chunk_size(size_t requested, bool is_class_space) {
1918   size_t chunk_sizes[] = {
1919       specialized_chunk_size(is_class_space),
1920       small_chunk_size(is_class_space),
1921       medium_chunk_size(is_class_space)
1922   };
1923 
1924   // Adjust up to one of the fixed chunk sizes ...
1925   for (size_t i = 0; i < ARRAY_SIZE(chunk_sizes); i++) {
1926     if (requested <= chunk_sizes[i]) {
1927       return chunk_sizes[i];
1928     }
1929   }
1930 
1931   // ... or return the size as a humongous chunk.
1932   return requested;
1933 }
1934 
1935 size_t SpaceManager::adjust_initial_chunk_size(size_t requested) const {
1936   return adjust_initial_chunk_size(requested, is_class());
1937 }
1938 
1939 size_t SpaceManager::get_initial_chunk_size(Metaspace::MetaspaceType type) const {
1940   size_t requested;
1941 
1942   if (is_class()) {
1943     switch (type) {
1944     case Metaspace::BootMetaspaceType:       requested = Metaspace::first_class_chunk_word_size(); break;
1945     case Metaspace::ROMetaspaceType:         requested = ClassSpecializedChunk; break;
1946     case Metaspace::ReadWriteMetaspaceType:  requested = ClassSpecializedChunk; break;
1947     case Metaspace::AnonymousMetaspaceType:  requested = ClassSpecializedChunk; break;
1948     case Metaspace::ReflectionMetaspaceType: requested = ClassSpecializedChunk; break;
1949     default:                                 requested = ClassSmallChunk; break;
1950     }
1951   } else {
1952     switch (type) {
1953     case Metaspace::BootMetaspaceType:       requested = Metaspace::first_chunk_word_size(); break;
1954     case Metaspace::ROMetaspaceType:         requested = SharedReadOnlySize / wordSize; break;
1955     case Metaspace::ReadWriteMetaspaceType:  requested = SharedReadWriteSize / wordSize; break;
1956     case Metaspace::AnonymousMetaspaceType:  requested = SpecializedChunk; break;
1957     case Metaspace::ReflectionMetaspaceType: requested = SpecializedChunk; break;
1958     default:                                 requested = SmallChunk; break;
1959     }
1960   }
1961 
1962   // Adjust to one of the fixed chunk sizes (unless humongous)
1963   const size_t adjusted = adjust_initial_chunk_size(requested);
1964 
1965   assert(adjusted != 0, err_msg("Incorrect initial chunk size. Requested: "
1966          SIZE_FORMAT " adjusted: " SIZE_FORMAT, requested, adjusted));
1967 
1968   return adjusted;
1969 }
1970 
1971 size_t SpaceManager::sum_free_in_chunks_in_use() const {
1972   MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag);
1973   size_t free = 0;
1974   for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) {
1975     Metachunk* chunk = chunks_in_use(i);
1976     while (chunk != NULL) {
1977       free += chunk->free_word_size();
1978       chunk = chunk->next();
1979     }
1980   }
1981   return free;
1982 }
1983 
1984 size_t SpaceManager::sum_waste_in_chunks_in_use() const {
1985   MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag);
1986   size_t result = 0;
1987   for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) {
1988    result += sum_waste_in_chunks_in_use(i);
1989   }
1990 
1991   return result;
1992 }
1993 
1994 size_t SpaceManager::sum_waste_in_chunks_in_use(ChunkIndex index) const {
1995   size_t result = 0;
1996   Metachunk* chunk = chunks_in_use(index);
1997   // Count the free space in all the chunk but not the
1998   // current chunk from which allocations are still being done.
1999   while (chunk != NULL) {
2000     if (chunk != current_chunk()) {
2001       result += chunk->free_word_size();
2002     }
2003     chunk = chunk->next();
2004   }
2005   return result;
2006 }
2007 
2008 size_t SpaceManager::sum_capacity_in_chunks_in_use() const {
2009   // For CMS use "allocated_chunks_words()" which does not need the
2010   // Metaspace lock.  For the other collectors sum over the
2011   // lists.  Use both methods as a check that "allocated_chunks_words()"
2012   // is correct.  That is, sum_capacity_in_chunks() is too expensive
2013   // to use in the product and allocated_chunks_words() should be used
2014   // but allow for  checking that allocated_chunks_words() returns the same
2015   // value as sum_capacity_in_chunks_in_use() which is the definitive
2016   // answer.
2017   if (UseConcMarkSweepGC) {
2018     return allocated_chunks_words();
2019   } else {
2020     MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag);
2021     size_t sum = 0;
2022     for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) {
2023       Metachunk* chunk = chunks_in_use(i);
2024       while (chunk != NULL) {
2025         sum += chunk->word_size();
2026         chunk = chunk->next();
2027       }
2028     }
2029   return sum;
2030   }
2031 }
2032 
2033 size_t SpaceManager::sum_count_in_chunks_in_use() {
2034   size_t count = 0;
2035   for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) {
2036     count = count + sum_count_in_chunks_in_use(i);
2037   }
2038 
2039   return count;
2040 }
2041 
2042 size_t SpaceManager::sum_count_in_chunks_in_use(ChunkIndex i) {
2043   size_t count = 0;
2044   Metachunk* chunk = chunks_in_use(i);
2045   while (chunk != NULL) {
2046     count++;
2047     chunk = chunk->next();
2048   }
2049   return count;
2050 }
2051 
2052 
2053 size_t SpaceManager::sum_used_in_chunks_in_use() const {
2054   MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag);
2055   size_t used = 0;
2056   for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) {
2057     Metachunk* chunk = chunks_in_use(i);
2058     while (chunk != NULL) {
2059       used += chunk->used_word_size();
2060       chunk = chunk->next();
2061     }
2062   }
2063   return used;
2064 }
2065 
2066 void SpaceManager::locked_print_chunks_in_use_on(outputStream* st) const {
2067 
2068   for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) {
2069     Metachunk* chunk = chunks_in_use(i);
2070     st->print("SpaceManager: %s " PTR_FORMAT,
2071                  chunk_size_name(i), chunk);
2072     if (chunk != NULL) {
2073       st->print_cr(" free " SIZE_FORMAT,
2074                    chunk->free_word_size());
2075     } else {
2076       st->cr();
2077     }
2078   }
2079 
2080   chunk_manager()->locked_print_free_chunks(st);
2081   chunk_manager()->locked_print_sum_free_chunks(st);
2082 }
2083 
2084 size_t SpaceManager::calc_chunk_size(size_t word_size) {
2085 
2086   // Decide between a small chunk and a medium chunk.  Up to
2087   // _small_chunk_limit small chunks can be allocated but
2088   // once a medium chunk has been allocated, no more small
2089   // chunks will be allocated.
2090   size_t chunk_word_size;
2091   if (chunks_in_use(MediumIndex) == NULL &&
2092       sum_count_in_chunks_in_use(SmallIndex) < _small_chunk_limit) {
2093     chunk_word_size = (size_t) small_chunk_size();
2094     if (word_size + Metachunk::overhead() > small_chunk_size()) {
2095       chunk_word_size = medium_chunk_size();
2096     }
2097   } else {
2098     chunk_word_size = medium_chunk_size();
2099   }
2100 
2101   // Might still need a humongous chunk.  Enforce
2102   // humongous allocations sizes to be aligned up to
2103   // the smallest chunk size.
2104   size_t if_humongous_sized_chunk =
2105     align_size_up(word_size + Metachunk::overhead(),
2106                   smallest_chunk_size());
2107   chunk_word_size =
2108     MAX2((size_t) chunk_word_size, if_humongous_sized_chunk);
2109 
2110   assert(!SpaceManager::is_humongous(word_size) ||
2111          chunk_word_size == if_humongous_sized_chunk,
2112          err_msg("Size calculation is wrong, word_size " SIZE_FORMAT
2113                  " chunk_word_size " SIZE_FORMAT,
2114                  word_size, chunk_word_size));
2115   if (TraceMetadataHumongousAllocation &&
2116       SpaceManager::is_humongous(word_size)) {
2117     gclog_or_tty->print_cr("Metadata humongous allocation:");
2118     gclog_or_tty->print_cr("  word_size " PTR_FORMAT, word_size);
2119     gclog_or_tty->print_cr("  chunk_word_size " PTR_FORMAT,
2120                            chunk_word_size);
2121     gclog_or_tty->print_cr("    chunk overhead " PTR_FORMAT,
2122                            Metachunk::overhead());
2123   }
2124   return chunk_word_size;
2125 }
2126 
2127 void SpaceManager::track_metaspace_memory_usage() {
2128   if (is_init_completed()) {
2129     if (is_class()) {
2130       MemoryService::track_compressed_class_memory_usage();
2131     }
2132     MemoryService::track_metaspace_memory_usage();
2133   }
2134 }
2135 
2136 MetaWord* SpaceManager::grow_and_allocate(size_t word_size) {
2137   assert(vs_list()->current_virtual_space() != NULL,
2138          "Should have been set");
2139   assert(current_chunk() == NULL ||
2140          current_chunk()->allocate(word_size) == NULL,
2141          "Don't need to expand");
2142   MutexLockerEx cl(SpaceManager::expand_lock(), Mutex::_no_safepoint_check_flag);
2143 
2144   if (TraceMetadataChunkAllocation && Verbose) {
2145     size_t words_left = 0;
2146     size_t words_used = 0;
2147     if (current_chunk() != NULL) {
2148       words_left = current_chunk()->free_word_size();
2149       words_used = current_chunk()->used_word_size();
2150     }
2151     gclog_or_tty->print_cr("SpaceManager::grow_and_allocate for " SIZE_FORMAT
2152                            " words " SIZE_FORMAT " words used " SIZE_FORMAT
2153                            " words left",
2154                             word_size, words_used, words_left);
2155   }
2156 
2157   // Get another chunk out of the virtual space
2158   size_t chunk_word_size = calc_chunk_size(word_size);
2159   Metachunk* next = get_new_chunk(chunk_word_size);
2160 
2161   MetaWord* mem = NULL;
2162 
2163   // If a chunk was available, add it to the in-use chunk list
2164   // and do an allocation from it.
2165   if (next != NULL) {
2166     // Add to this manager's list of chunks in use.
2167     add_chunk(next, false);
2168     mem = next->allocate(word_size);
2169   }
2170 
2171   // Track metaspace memory usage statistic.
2172   track_metaspace_memory_usage();
2173 
2174   return mem;
2175 }
2176 
2177 void SpaceManager::print_on(outputStream* st) const {
2178 
2179   for (ChunkIndex i = ZeroIndex;
2180        i < NumberOfInUseLists ;
2181        i = next_chunk_index(i) ) {
2182     st->print_cr("  chunks_in_use " PTR_FORMAT " chunk size " PTR_FORMAT,
2183                  chunks_in_use(i),
2184                  chunks_in_use(i) == NULL ? 0 : chunks_in_use(i)->word_size());
2185   }
2186   st->print_cr("    waste:  Small " SIZE_FORMAT " Medium " SIZE_FORMAT
2187                " Humongous " SIZE_FORMAT,
2188                sum_waste_in_chunks_in_use(SmallIndex),
2189                sum_waste_in_chunks_in_use(MediumIndex),
2190                sum_waste_in_chunks_in_use(HumongousIndex));
2191   // block free lists
2192   if (block_freelists() != NULL) {
2193     st->print_cr("total in block free lists " SIZE_FORMAT,
2194       block_freelists()->total_size());
2195   }
2196 }
2197 
2198 SpaceManager::SpaceManager(Metaspace::MetadataType mdtype,
2199                            Mutex* lock) :
2200   _mdtype(mdtype),
2201   _allocated_blocks_words(0),
2202   _allocated_chunks_words(0),
2203   _allocated_chunks_count(0),
2204   _lock(lock)
2205 {
2206   initialize();
2207 }
2208 
2209 void SpaceManager::inc_size_metrics(size_t words) {
2210   assert_lock_strong(SpaceManager::expand_lock());
2211   // Total of allocated Metachunks and allocated Metachunks count
2212   // for each SpaceManager
2213   _allocated_chunks_words = _allocated_chunks_words + words;
2214   _allocated_chunks_count++;
2215   // Global total of capacity in allocated Metachunks
2216   MetaspaceAux::inc_capacity(mdtype(), words);
2217   // Global total of allocated Metablocks.
2218   // used_words_slow() includes the overhead in each
2219   // Metachunk so include it in the used when the
2220   // Metachunk is first added (so only added once per
2221   // Metachunk).
2222   MetaspaceAux::inc_used(mdtype(), Metachunk::overhead());
2223 }
2224 
2225 void SpaceManager::inc_used_metrics(size_t words) {
2226   // Add to the per SpaceManager total
2227   Atomic::add_ptr(words, &_allocated_blocks_words);
2228   // Add to the global total
2229   MetaspaceAux::inc_used(mdtype(), words);
2230 }
2231 
2232 void SpaceManager::dec_total_from_size_metrics() {
2233   MetaspaceAux::dec_capacity(mdtype(), allocated_chunks_words());
2234   MetaspaceAux::dec_used(mdtype(), allocated_blocks_words());
2235   // Also deduct the overhead per Metachunk
2236   MetaspaceAux::dec_used(mdtype(), allocated_chunks_count() * Metachunk::overhead());
2237 }
2238 
2239 void SpaceManager::initialize() {
2240   Metadebug::init_allocation_fail_alot_count();
2241   for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) {
2242     _chunks_in_use[i] = NULL;
2243   }
2244   _current_chunk = NULL;
2245   if (TraceMetadataChunkAllocation && Verbose) {
2246     gclog_or_tty->print_cr("SpaceManager(): " PTR_FORMAT, this);
2247   }
2248 }
2249 
2250 void ChunkManager::return_chunks(ChunkIndex index, Metachunk* chunks) {
2251   if (chunks == NULL) {
2252     return;
2253   }
2254   ChunkList* list = free_chunks(index);
2255   assert(list->size() == chunks->word_size(), "Mismatch in chunk sizes");
2256   assert_lock_strong(SpaceManager::expand_lock());
2257   Metachunk* cur = chunks;
2258 
2259   // This returns chunks one at a time.  If a new
2260   // class List can be created that is a base class
2261   // of FreeList then something like FreeList::prepend()
2262   // can be used in place of this loop
2263   while (cur != NULL) {
2264     assert(cur->container() != NULL, "Container should have been set");
2265     cur->container()->dec_container_count();
2266     // Capture the next link before it is changed
2267     // by the call to return_chunk_at_head();
2268     Metachunk* next = cur->next();
2269     DEBUG_ONLY(cur->set_is_tagged_free(true);)
2270     list->return_chunk_at_head(cur);
2271     cur = next;
2272   }
2273 }
2274 
2275 SpaceManager::~SpaceManager() {
2276   // This call this->_lock which can't be done while holding expand_lock()
2277   assert(sum_capacity_in_chunks_in_use() == allocated_chunks_words(),
2278     err_msg("sum_capacity_in_chunks_in_use() " SIZE_FORMAT
2279             " allocated_chunks_words() " SIZE_FORMAT,
2280             sum_capacity_in_chunks_in_use(), allocated_chunks_words()));
2281 
2282   MutexLockerEx fcl(SpaceManager::expand_lock(),
2283                     Mutex::_no_safepoint_check_flag);
2284 
2285   chunk_manager()->slow_locked_verify();
2286 
2287   dec_total_from_size_metrics();
2288 
2289   if (TraceMetadataChunkAllocation && Verbose) {
2290     gclog_or_tty->print_cr("~SpaceManager(): " PTR_FORMAT, this);
2291     locked_print_chunks_in_use_on(gclog_or_tty);
2292   }
2293 
2294   // Do not mangle freed Metachunks.  The chunk size inside Metachunks
2295   // is during the freeing of a VirtualSpaceNodes.
2296 
2297   // Have to update before the chunks_in_use lists are emptied
2298   // below.
2299   chunk_manager()->inc_free_chunks_total(allocated_chunks_words(),
2300                                          sum_count_in_chunks_in_use());
2301 
2302   // Add all the chunks in use by this space manager
2303   // to the global list of free chunks.
2304 
2305   // Follow each list of chunks-in-use and add them to the
2306   // free lists.  Each list is NULL terminated.
2307 
2308   for (ChunkIndex i = ZeroIndex; i < HumongousIndex; i = next_chunk_index(i)) {
2309     if (TraceMetadataChunkAllocation && Verbose) {
2310       gclog_or_tty->print_cr("returned %d %s chunks to freelist",
2311                              sum_count_in_chunks_in_use(i),
2312                              chunk_size_name(i));
2313     }
2314     Metachunk* chunks = chunks_in_use(i);
2315     chunk_manager()->return_chunks(i, chunks);
2316     set_chunks_in_use(i, NULL);
2317     if (TraceMetadataChunkAllocation && Verbose) {
2318       gclog_or_tty->print_cr("updated freelist count %d %s",
2319                              chunk_manager()->free_chunks(i)->count(),
2320                              chunk_size_name(i));
2321     }
2322     assert(i != HumongousIndex, "Humongous chunks are handled explicitly later");
2323   }
2324 
2325   // The medium chunk case may be optimized by passing the head and
2326   // tail of the medium chunk list to add_at_head().  The tail is often
2327   // the current chunk but there are probably exceptions.
2328 
2329   // Humongous chunks
2330   if (TraceMetadataChunkAllocation && Verbose) {
2331     gclog_or_tty->print_cr("returned %d %s humongous chunks to dictionary",
2332                             sum_count_in_chunks_in_use(HumongousIndex),
2333                             chunk_size_name(HumongousIndex));
2334     gclog_or_tty->print("Humongous chunk dictionary: ");
2335   }
2336   // Humongous chunks are never the current chunk.
2337   Metachunk* humongous_chunks = chunks_in_use(HumongousIndex);
2338 
2339   while (humongous_chunks != NULL) {
2340 #ifdef ASSERT
2341     humongous_chunks->set_is_tagged_free(true);
2342 #endif
2343     if (TraceMetadataChunkAllocation && Verbose) {
2344       gclog_or_tty->print(PTR_FORMAT " (" SIZE_FORMAT ") ",
2345                           humongous_chunks,
2346                           humongous_chunks->word_size());
2347     }
2348     assert(humongous_chunks->word_size() == (size_t)
2349            align_size_up(humongous_chunks->word_size(),
2350                              smallest_chunk_size()),
2351            err_msg("Humongous chunk size is wrong: word size " SIZE_FORMAT
2352                    " granularity %d",
2353                    humongous_chunks->word_size(), smallest_chunk_size()));
2354     Metachunk* next_humongous_chunks = humongous_chunks->next();
2355     humongous_chunks->container()->dec_container_count();
2356     chunk_manager()->humongous_dictionary()->return_chunk(humongous_chunks);
2357     humongous_chunks = next_humongous_chunks;
2358   }
2359   if (TraceMetadataChunkAllocation && Verbose) {
2360     gclog_or_tty->cr();
2361     gclog_or_tty->print_cr("updated dictionary count %d %s",
2362                      chunk_manager()->humongous_dictionary()->total_count(),
2363                      chunk_size_name(HumongousIndex));
2364   }
2365   chunk_manager()->slow_locked_verify();
2366 }
2367 
2368 const char* SpaceManager::chunk_size_name(ChunkIndex index) const {
2369   switch (index) {
2370     case SpecializedIndex:
2371       return "Specialized";
2372     case SmallIndex:
2373       return "Small";
2374     case MediumIndex:
2375       return "Medium";
2376     case HumongousIndex:
2377       return "Humongous";
2378     default:
2379       return NULL;
2380   }
2381 }
2382 
2383 ChunkIndex ChunkManager::list_index(size_t size) {
2384   if (free_chunks(SpecializedIndex)->size() == size) {
2385     return SpecializedIndex;
2386   }
2387   if (free_chunks(SmallIndex)->size() == size) {
2388     return SmallIndex;
2389   }
2390   if (free_chunks(MediumIndex)->size() == size) {
2391     return MediumIndex;
2392   }
2393 
2394   assert(size > free_chunks(MediumIndex)->size(), "Not a humongous chunk");
2395   return HumongousIndex;
2396 }
2397 
2398 void SpaceManager::deallocate(MetaWord* p, size_t word_size) {
2399   assert_lock_strong(_lock);
2400   size_t raw_word_size = get_raw_word_size(word_size);
2401   size_t min_size = TreeChunk<Metablock, FreeList<Metablock> >::min_size();
2402   assert(raw_word_size >= min_size,
2403          err_msg("Should not deallocate dark matter " SIZE_FORMAT "<" SIZE_FORMAT, word_size, min_size));
2404   block_freelists()->return_block(p, raw_word_size);
2405 }
2406 
2407 // Adds a chunk to the list of chunks in use.
2408 void SpaceManager::add_chunk(Metachunk* new_chunk, bool make_current) {
2409 
2410   assert(new_chunk != NULL, "Should not be NULL");
2411   assert(new_chunk->next() == NULL, "Should not be on a list");
2412 
2413   new_chunk->reset_empty();
2414 
2415   // Find the correct list and and set the current
2416   // chunk for that list.
2417   ChunkIndex index = chunk_manager()->list_index(new_chunk->word_size());
2418 
2419   if (index != HumongousIndex) {
2420     retire_current_chunk();
2421     set_current_chunk(new_chunk);
2422     new_chunk->set_next(chunks_in_use(index));
2423     set_chunks_in_use(index, new_chunk);
2424   } else {
2425     // For null class loader data and DumpSharedSpaces, the first chunk isn't
2426     // small, so small will be null.  Link this first chunk as the current
2427     // chunk.
2428     if (make_current) {
2429       // Set as the current chunk but otherwise treat as a humongous chunk.
2430       set_current_chunk(new_chunk);
2431     }
2432     // Link at head.  The _current_chunk only points to a humongous chunk for
2433     // the null class loader metaspace (class and data virtual space managers)
2434     // any humongous chunks so will not point to the tail
2435     // of the humongous chunks list.
2436     new_chunk->set_next(chunks_in_use(HumongousIndex));
2437     set_chunks_in_use(HumongousIndex, new_chunk);
2438 
2439     assert(new_chunk->word_size() > medium_chunk_size(), "List inconsistency");
2440   }
2441 
2442   // Add to the running sum of capacity
2443   inc_size_metrics(new_chunk->word_size());
2444 
2445   assert(new_chunk->is_empty(), "Not ready for reuse");
2446   if (TraceMetadataChunkAllocation && Verbose) {
2447     gclog_or_tty->print("SpaceManager::add_chunk: %d) ",
2448                         sum_count_in_chunks_in_use());
2449     new_chunk->print_on(gclog_or_tty);
2450     chunk_manager()->locked_print_free_chunks(gclog_or_tty);
2451   }
2452 }
2453 
2454 void SpaceManager::retire_current_chunk() {
2455   if (current_chunk() != NULL) {
2456     size_t remaining_words = current_chunk()->free_word_size();
2457     if (remaining_words >= TreeChunk<Metablock, FreeList<Metablock> >::min_size()) {
2458       block_freelists()->return_block(current_chunk()->allocate(remaining_words), remaining_words);
2459       inc_used_metrics(remaining_words);
2460     }
2461   }
2462 }
2463 
2464 Metachunk* SpaceManager::get_new_chunk(size_t chunk_word_size) {
2465   // Get a chunk from the chunk freelist
2466   Metachunk* next = chunk_manager()->chunk_freelist_allocate(chunk_word_size);
2467 
2468   if (next == NULL) {
2469     next = vs_list()->get_new_chunk(chunk_word_size,
2470                                     medium_chunk_bunch());
2471   }
2472 
2473   if (TraceMetadataHumongousAllocation && next != NULL &&
2474       SpaceManager::is_humongous(next->word_size())) {
2475     gclog_or_tty->print_cr("  new humongous chunk word size "
2476                            PTR_FORMAT, next->word_size());
2477   }
2478 
2479   return next;
2480 }
2481 
2482 MetaWord* SpaceManager::allocate(size_t word_size) {
2483   MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag);
2484 
2485   size_t raw_word_size = get_raw_word_size(word_size);
2486   BlockFreelist* fl =  block_freelists();
2487   MetaWord* p = NULL;
2488   // Allocation from the dictionary is expensive in the sense that
2489   // the dictionary has to be searched for a size.  Don't allocate
2490   // from the dictionary until it starts to get fat.  Is this
2491   // a reasonable policy?  Maybe an skinny dictionary is fast enough
2492   // for allocations.  Do some profiling.  JJJ
2493   if (fl->total_size() > allocation_from_dictionary_limit) {
2494     p = fl->get_block(raw_word_size);
2495   }
2496   if (p == NULL) {
2497     p = allocate_work(raw_word_size);
2498   }
2499 
2500   return p;
2501 }
2502 
2503 // Returns the address of spaced allocated for "word_size".
2504 // This methods does not know about blocks (Metablocks)
2505 MetaWord* SpaceManager::allocate_work(size_t word_size) {
2506   assert_lock_strong(_lock);
2507 #ifdef ASSERT
2508   if (Metadebug::test_metadata_failure()) {
2509     return NULL;
2510   }
2511 #endif
2512   // Is there space in the current chunk?
2513   MetaWord* result = NULL;
2514 
2515   // For DumpSharedSpaces, only allocate out of the current chunk which is
2516   // never null because we gave it the size we wanted.   Caller reports out
2517   // of memory if this returns null.
2518   if (DumpSharedSpaces) {
2519     assert(current_chunk() != NULL, "should never happen");
2520     inc_used_metrics(word_size);
2521     return current_chunk()->allocate(word_size); // caller handles null result
2522   }
2523 
2524   if (current_chunk() != NULL) {
2525     result = current_chunk()->allocate(word_size);
2526   }
2527 
2528   if (result == NULL) {
2529     result = grow_and_allocate(word_size);
2530   }
2531 
2532   if (result != NULL) {
2533     inc_used_metrics(word_size);
2534     assert(result != (MetaWord*) chunks_in_use(MediumIndex),
2535            "Head of the list is being allocated");
2536   }
2537 
2538   return result;
2539 }
2540 
2541 void SpaceManager::verify() {
2542   // If there are blocks in the dictionary, then
2543   // verfication of chunks does not work since
2544   // being in the dictionary alters a chunk.
2545   if (block_freelists()->total_size() == 0) {
2546     for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) {
2547       Metachunk* curr = chunks_in_use(i);
2548       while (curr != NULL) {
2549         curr->verify();
2550         verify_chunk_size(curr);
2551         curr = curr->next();
2552       }
2553     }
2554   }
2555 }
2556 
2557 void SpaceManager::verify_chunk_size(Metachunk* chunk) {
2558   assert(is_humongous(chunk->word_size()) ||
2559          chunk->word_size() == medium_chunk_size() ||
2560          chunk->word_size() == small_chunk_size() ||
2561          chunk->word_size() == specialized_chunk_size(),
2562          "Chunk size is wrong");
2563   return;
2564 }
2565 
2566 #ifdef ASSERT
2567 void SpaceManager::verify_allocated_blocks_words() {
2568   // Verification is only guaranteed at a safepoint.
2569   assert(SafepointSynchronize::is_at_safepoint() || !Universe::is_fully_initialized(),
2570     "Verification can fail if the applications is running");
2571   assert(allocated_blocks_words() == sum_used_in_chunks_in_use(),
2572     err_msg("allocation total is not consistent " SIZE_FORMAT
2573             " vs " SIZE_FORMAT,
2574             allocated_blocks_words(), sum_used_in_chunks_in_use()));
2575 }
2576 
2577 #endif
2578 
2579 void SpaceManager::dump(outputStream* const out) const {
2580   size_t curr_total = 0;
2581   size_t waste = 0;
2582   uint i = 0;
2583   size_t used = 0;
2584   size_t capacity = 0;
2585 
2586   // Add up statistics for all chunks in this SpaceManager.
2587   for (ChunkIndex index = ZeroIndex;
2588        index < NumberOfInUseLists;
2589        index = next_chunk_index(index)) {
2590     for (Metachunk* curr = chunks_in_use(index);
2591          curr != NULL;
2592          curr = curr->next()) {
2593       out->print("%d) ", i++);
2594       curr->print_on(out);
2595       curr_total += curr->word_size();
2596       used += curr->used_word_size();
2597       capacity += curr->word_size();
2598       waste += curr->free_word_size() + curr->overhead();;
2599     }
2600   }
2601 
2602   if (TraceMetadataChunkAllocation && Verbose) {
2603     block_freelists()->print_on(out);
2604   }
2605 
2606   size_t free = current_chunk() == NULL ? 0 : current_chunk()->free_word_size();
2607   // Free space isn't wasted.
2608   waste -= free;
2609 
2610   out->print_cr("total of all chunks "  SIZE_FORMAT " used " SIZE_FORMAT
2611                 " free " SIZE_FORMAT " capacity " SIZE_FORMAT
2612                 " waste " SIZE_FORMAT, curr_total, used, free, capacity, waste);
2613 }
2614 
2615 #ifndef PRODUCT
2616 void SpaceManager::mangle_freed_chunks() {
2617   for (ChunkIndex index = ZeroIndex;
2618        index < NumberOfInUseLists;
2619        index = next_chunk_index(index)) {
2620     for (Metachunk* curr = chunks_in_use(index);
2621          curr != NULL;
2622          curr = curr->next()) {
2623       curr->mangle();
2624     }
2625   }
2626 }
2627 #endif // PRODUCT
2628 
2629 // MetaspaceAux
2630 
2631 
2632 size_t MetaspaceAux::_capacity_words[] = {0, 0};
2633 size_t MetaspaceAux::_used_words[] = {0, 0};
2634 
2635 size_t MetaspaceAux::free_bytes(Metaspace::MetadataType mdtype) {
2636   VirtualSpaceList* list = Metaspace::get_space_list(mdtype);
2637   return list == NULL ? 0 : list->free_bytes();
2638 }
2639 
2640 size_t MetaspaceAux::free_bytes() {
2641   return free_bytes(Metaspace::ClassType) + free_bytes(Metaspace::NonClassType);
2642 }
2643 
2644 void MetaspaceAux::dec_capacity(Metaspace::MetadataType mdtype, size_t words) {
2645   assert_lock_strong(SpaceManager::expand_lock());
2646   assert(words <= capacity_words(mdtype),
2647     err_msg("About to decrement below 0: words " SIZE_FORMAT
2648             " is greater than _capacity_words[%u] " SIZE_FORMAT,
2649             words, mdtype, capacity_words(mdtype)));
2650   _capacity_words[mdtype] -= words;
2651 }
2652 
2653 void MetaspaceAux::inc_capacity(Metaspace::MetadataType mdtype, size_t words) {
2654   assert_lock_strong(SpaceManager::expand_lock());
2655   // Needs to be atomic
2656   _capacity_words[mdtype] += words;
2657 }
2658 
2659 void MetaspaceAux::dec_used(Metaspace::MetadataType mdtype, size_t words) {
2660   assert(words <= used_words(mdtype),
2661     err_msg("About to decrement below 0: words " SIZE_FORMAT
2662             " is greater than _used_words[%u] " SIZE_FORMAT,
2663             words, mdtype, used_words(mdtype)));
2664   // For CMS deallocation of the Metaspaces occurs during the
2665   // sweep which is a concurrent phase.  Protection by the expand_lock()
2666   // is not enough since allocation is on a per Metaspace basis
2667   // and protected by the Metaspace lock.
2668   jlong minus_words = (jlong) - (jlong) words;
2669   Atomic::add_ptr(minus_words, &_used_words[mdtype]);
2670 }
2671 
2672 void MetaspaceAux::inc_used(Metaspace::MetadataType mdtype, size_t words) {
2673   // _used_words tracks allocations for
2674   // each piece of metadata.  Those allocations are
2675   // generally done concurrently by different application
2676   // threads so must be done atomically.
2677   Atomic::add_ptr(words, &_used_words[mdtype]);
2678 }
2679 
2680 size_t MetaspaceAux::used_bytes_slow(Metaspace::MetadataType mdtype) {
2681   size_t used = 0;
2682   ClassLoaderDataGraphMetaspaceIterator iter;
2683   while (iter.repeat()) {
2684     Metaspace* msp = iter.get_next();
2685     // Sum allocated_blocks_words for each metaspace
2686     if (msp != NULL) {
2687       used += msp->used_words_slow(mdtype);
2688     }
2689   }
2690   return used * BytesPerWord;
2691 }
2692 
2693 size_t MetaspaceAux::free_bytes_slow(Metaspace::MetadataType mdtype) {
2694   size_t free = 0;
2695   ClassLoaderDataGraphMetaspaceIterator iter;
2696   while (iter.repeat()) {
2697     Metaspace* msp = iter.get_next();
2698     if (msp != NULL) {
2699       free += msp->free_words_slow(mdtype);
2700     }
2701   }
2702   return free * BytesPerWord;
2703 }
2704 
2705 size_t MetaspaceAux::capacity_bytes_slow(Metaspace::MetadataType mdtype) {
2706   if ((mdtype == Metaspace::ClassType) && !Metaspace::using_class_space()) {
2707     return 0;
2708   }
2709   // Don't count the space in the freelists.  That space will be
2710   // added to the capacity calculation as needed.
2711   size_t capacity = 0;
2712   ClassLoaderDataGraphMetaspaceIterator iter;
2713   while (iter.repeat()) {
2714     Metaspace* msp = iter.get_next();
2715     if (msp != NULL) {
2716       capacity += msp->capacity_words_slow(mdtype);
2717     }
2718   }
2719   return capacity * BytesPerWord;
2720 }
2721 
2722 size_t MetaspaceAux::capacity_bytes_slow() {
2723 #ifdef PRODUCT
2724   // Use capacity_bytes() in PRODUCT instead of this function.
2725   guarantee(false, "Should not call capacity_bytes_slow() in the PRODUCT");
2726 #endif
2727   size_t class_capacity = capacity_bytes_slow(Metaspace::ClassType);
2728   size_t non_class_capacity = capacity_bytes_slow(Metaspace::NonClassType);
2729   assert(capacity_bytes() == class_capacity + non_class_capacity,
2730       err_msg("bad accounting: capacity_bytes() " SIZE_FORMAT
2731         " class_capacity + non_class_capacity " SIZE_FORMAT
2732         " class_capacity " SIZE_FORMAT " non_class_capacity " SIZE_FORMAT,
2733         capacity_bytes(), class_capacity + non_class_capacity,
2734         class_capacity, non_class_capacity));
2735 
2736   return class_capacity + non_class_capacity;
2737 }
2738 
2739 size_t MetaspaceAux::reserved_bytes(Metaspace::MetadataType mdtype) {
2740   VirtualSpaceList* list = Metaspace::get_space_list(mdtype);
2741   return list == NULL ? 0 : list->reserved_bytes();
2742 }
2743 
2744 size_t MetaspaceAux::committed_bytes(Metaspace::MetadataType mdtype) {
2745   VirtualSpaceList* list = Metaspace::get_space_list(mdtype);
2746   return list == NULL ? 0 : list->committed_bytes();
2747 }
2748 
2749 size_t MetaspaceAux::min_chunk_size_words() { return Metaspace::first_chunk_word_size(); }
2750 
2751 size_t MetaspaceAux::free_chunks_total_words(Metaspace::MetadataType mdtype) {
2752   ChunkManager* chunk_manager = Metaspace::get_chunk_manager(mdtype);
2753   if (chunk_manager == NULL) {
2754     return 0;
2755   }
2756   chunk_manager->slow_verify();
2757   return chunk_manager->free_chunks_total_words();
2758 }
2759 
2760 size_t MetaspaceAux::free_chunks_total_bytes(Metaspace::MetadataType mdtype) {
2761   return free_chunks_total_words(mdtype) * BytesPerWord;
2762 }
2763 
2764 size_t MetaspaceAux::free_chunks_total_words() {
2765   return free_chunks_total_words(Metaspace::ClassType) +
2766          free_chunks_total_words(Metaspace::NonClassType);
2767 }
2768 
2769 size_t MetaspaceAux::free_chunks_total_bytes() {
2770   return free_chunks_total_words() * BytesPerWord;
2771 }
2772 
2773 bool MetaspaceAux::has_chunk_free_list(Metaspace::MetadataType mdtype) {
2774   return Metaspace::get_chunk_manager(mdtype) != NULL;
2775 }
2776 
2777 MetaspaceChunkFreeListSummary MetaspaceAux::chunk_free_list_summary(Metaspace::MetadataType mdtype) {
2778   if (!has_chunk_free_list(mdtype)) {
2779     return MetaspaceChunkFreeListSummary();
2780   }
2781 
2782   const ChunkManager* cm = Metaspace::get_chunk_manager(mdtype);
2783   return cm->chunk_free_list_summary();
2784 }
2785 
2786 void MetaspaceAux::print_metaspace_change(size_t prev_metadata_used) {
2787   gclog_or_tty->print(", [Metaspace:");
2788   if (PrintGCDetails && Verbose) {
2789     gclog_or_tty->print(" "  SIZE_FORMAT
2790                         "->" SIZE_FORMAT
2791                         "("  SIZE_FORMAT ")",
2792                         prev_metadata_used,
2793                         used_bytes(),
2794                         reserved_bytes());
2795   } else {
2796     gclog_or_tty->print(" "  SIZE_FORMAT "K"
2797                         "->" SIZE_FORMAT "K"
2798                         "("  SIZE_FORMAT "K)",
2799                         prev_metadata_used/K,
2800                         used_bytes()/K,
2801                         reserved_bytes()/K);
2802   }
2803 
2804   gclog_or_tty->print("]");
2805 }
2806 
2807 // This is printed when PrintGCDetails
2808 void MetaspaceAux::print_on(outputStream* out) {
2809   Metaspace::MetadataType nct = Metaspace::NonClassType;
2810 
2811   out->print_cr(" Metaspace       "
2812                 "used "      SIZE_FORMAT "K, "
2813                 "capacity "  SIZE_FORMAT "K, "
2814                 "committed " SIZE_FORMAT "K, "
2815                 "reserved "  SIZE_FORMAT "K",
2816                 used_bytes()/K,
2817                 capacity_bytes()/K,
2818                 committed_bytes()/K,
2819                 reserved_bytes()/K);
2820 
2821   if (Metaspace::using_class_space()) {
2822     Metaspace::MetadataType ct = Metaspace::ClassType;
2823     out->print_cr("  class space    "
2824                   "used "      SIZE_FORMAT "K, "
2825                   "capacity "  SIZE_FORMAT "K, "
2826                   "committed " SIZE_FORMAT "K, "
2827                   "reserved "  SIZE_FORMAT "K",
2828                   used_bytes(ct)/K,
2829                   capacity_bytes(ct)/K,
2830                   committed_bytes(ct)/K,
2831                   reserved_bytes(ct)/K);
2832   }
2833 }
2834 
2835 // Print information for class space and data space separately.
2836 // This is almost the same as above.
2837 void MetaspaceAux::print_on(outputStream* out, Metaspace::MetadataType mdtype) {
2838   size_t free_chunks_capacity_bytes = free_chunks_total_bytes(mdtype);
2839   size_t capacity_bytes = capacity_bytes_slow(mdtype);
2840   size_t used_bytes = used_bytes_slow(mdtype);
2841   size_t free_bytes = free_bytes_slow(mdtype);
2842   size_t used_and_free = used_bytes + free_bytes +
2843                            free_chunks_capacity_bytes;
2844   out->print_cr("  Chunk accounting: used in chunks " SIZE_FORMAT
2845              "K + unused in chunks " SIZE_FORMAT "K  + "
2846              " capacity in free chunks " SIZE_FORMAT "K = " SIZE_FORMAT
2847              "K  capacity in allocated chunks " SIZE_FORMAT "K",
2848              used_bytes / K,
2849              free_bytes / K,
2850              free_chunks_capacity_bytes / K,
2851              used_and_free / K,
2852              capacity_bytes / K);
2853   // Accounting can only be correct if we got the values during a safepoint
2854   assert(!SafepointSynchronize::is_at_safepoint() || used_and_free == capacity_bytes, "Accounting is wrong");
2855 }
2856 
2857 // Print total fragmentation for class metaspaces
2858 void MetaspaceAux::print_class_waste(outputStream* out) {
2859   assert(Metaspace::using_class_space(), "class metaspace not used");
2860   size_t cls_specialized_waste = 0, cls_small_waste = 0, cls_medium_waste = 0;
2861   size_t cls_specialized_count = 0, cls_small_count = 0, cls_medium_count = 0, cls_humongous_count = 0;
2862   ClassLoaderDataGraphMetaspaceIterator iter;
2863   while (iter.repeat()) {
2864     Metaspace* msp = iter.get_next();
2865     if (msp != NULL) {
2866       cls_specialized_waste += msp->class_vsm()->sum_waste_in_chunks_in_use(SpecializedIndex);
2867       cls_specialized_count += msp->class_vsm()->sum_count_in_chunks_in_use(SpecializedIndex);
2868       cls_small_waste += msp->class_vsm()->sum_waste_in_chunks_in_use(SmallIndex);
2869       cls_small_count += msp->class_vsm()->sum_count_in_chunks_in_use(SmallIndex);
2870       cls_medium_waste += msp->class_vsm()->sum_waste_in_chunks_in_use(MediumIndex);
2871       cls_medium_count += msp->class_vsm()->sum_count_in_chunks_in_use(MediumIndex);
2872       cls_humongous_count += msp->class_vsm()->sum_count_in_chunks_in_use(HumongousIndex);
2873     }
2874   }
2875   out->print_cr(" class: " SIZE_FORMAT " specialized(s) " SIZE_FORMAT ", "
2876                 SIZE_FORMAT " small(s) " SIZE_FORMAT ", "
2877                 SIZE_FORMAT " medium(s) " SIZE_FORMAT ", "
2878                 "large count " SIZE_FORMAT,
2879                 cls_specialized_count, cls_specialized_waste,
2880                 cls_small_count, cls_small_waste,
2881                 cls_medium_count, cls_medium_waste, cls_humongous_count);
2882 }
2883 
2884 // Print total fragmentation for data and class metaspaces separately
2885 void MetaspaceAux::print_waste(outputStream* out) {
2886   size_t specialized_waste = 0, small_waste = 0, medium_waste = 0;
2887   size_t specialized_count = 0, small_count = 0, medium_count = 0, humongous_count = 0;
2888 
2889   ClassLoaderDataGraphMetaspaceIterator iter;
2890   while (iter.repeat()) {
2891     Metaspace* msp = iter.get_next();
2892     if (msp != NULL) {
2893       specialized_waste += msp->vsm()->sum_waste_in_chunks_in_use(SpecializedIndex);
2894       specialized_count += msp->vsm()->sum_count_in_chunks_in_use(SpecializedIndex);
2895       small_waste += msp->vsm()->sum_waste_in_chunks_in_use(SmallIndex);
2896       small_count += msp->vsm()->sum_count_in_chunks_in_use(SmallIndex);
2897       medium_waste += msp->vsm()->sum_waste_in_chunks_in_use(MediumIndex);
2898       medium_count += msp->vsm()->sum_count_in_chunks_in_use(MediumIndex);
2899       humongous_count += msp->vsm()->sum_count_in_chunks_in_use(HumongousIndex);
2900     }
2901   }
2902   out->print_cr("Total fragmentation waste (words) doesn't count free space");
2903   out->print_cr("  data: " SIZE_FORMAT " specialized(s) " SIZE_FORMAT ", "
2904                         SIZE_FORMAT " small(s) " SIZE_FORMAT ", "
2905                         SIZE_FORMAT " medium(s) " SIZE_FORMAT ", "
2906                         "large count " SIZE_FORMAT,
2907              specialized_count, specialized_waste, small_count,
2908              small_waste, medium_count, medium_waste, humongous_count);
2909   if (Metaspace::using_class_space()) {
2910     print_class_waste(out);
2911   }
2912 }
2913 
2914 // Dump global metaspace things from the end of ClassLoaderDataGraph
2915 void MetaspaceAux::dump(outputStream* out) {
2916   out->print_cr("All Metaspace:");
2917   out->print("data space: "); print_on(out, Metaspace::NonClassType);
2918   out->print("class space: "); print_on(out, Metaspace::ClassType);
2919   print_waste(out);
2920 }
2921 
2922 void MetaspaceAux::verify_free_chunks() {
2923   Metaspace::chunk_manager_metadata()->verify();
2924   if (Metaspace::using_class_space()) {
2925     Metaspace::chunk_manager_class()->verify();
2926   }
2927 }
2928 
2929 void MetaspaceAux::verify_capacity() {
2930 #ifdef ASSERT
2931   size_t running_sum_capacity_bytes = capacity_bytes();
2932   // For purposes of the running sum of capacity, verify against capacity
2933   size_t capacity_in_use_bytes = capacity_bytes_slow();
2934   assert(running_sum_capacity_bytes == capacity_in_use_bytes,
2935     err_msg("capacity_words() * BytesPerWord " SIZE_FORMAT
2936             " capacity_bytes_slow()" SIZE_FORMAT,
2937             running_sum_capacity_bytes, capacity_in_use_bytes));
2938   for (Metaspace::MetadataType i = Metaspace::ClassType;
2939        i < Metaspace:: MetadataTypeCount;
2940        i = (Metaspace::MetadataType)(i + 1)) {
2941     size_t capacity_in_use_bytes = capacity_bytes_slow(i);
2942     assert(capacity_bytes(i) == capacity_in_use_bytes,
2943       err_msg("capacity_bytes(%u) " SIZE_FORMAT
2944               " capacity_bytes_slow(%u)" SIZE_FORMAT,
2945               i, capacity_bytes(i), i, capacity_in_use_bytes));
2946   }
2947 #endif
2948 }
2949 
2950 void MetaspaceAux::verify_used() {
2951 #ifdef ASSERT
2952   size_t running_sum_used_bytes = used_bytes();
2953   // For purposes of the running sum of used, verify against used
2954   size_t used_in_use_bytes = used_bytes_slow();
2955   assert(used_bytes() == used_in_use_bytes,
2956     err_msg("used_bytes() " SIZE_FORMAT
2957             " used_bytes_slow()" SIZE_FORMAT,
2958             used_bytes(), used_in_use_bytes));
2959   for (Metaspace::MetadataType i = Metaspace::ClassType;
2960        i < Metaspace:: MetadataTypeCount;
2961        i = (Metaspace::MetadataType)(i + 1)) {
2962     size_t used_in_use_bytes = used_bytes_slow(i);
2963     assert(used_bytes(i) == used_in_use_bytes,
2964       err_msg("used_bytes(%u) " SIZE_FORMAT
2965               " used_bytes_slow(%u)" SIZE_FORMAT,
2966               i, used_bytes(i), i, used_in_use_bytes));
2967   }
2968 #endif
2969 }
2970 
2971 void MetaspaceAux::verify_metrics() {
2972   verify_capacity();
2973   verify_used();
2974 }
2975 
2976 
2977 // Metaspace methods
2978 
2979 size_t Metaspace::_first_chunk_word_size = 0;
2980 size_t Metaspace::_first_class_chunk_word_size = 0;
2981 
2982 size_t Metaspace::_commit_alignment = 0;
2983 size_t Metaspace::_reserve_alignment = 0;
2984 
2985 Metaspace::Metaspace(Mutex* lock, MetaspaceType type) {
2986   initialize(lock, type);
2987 }
2988 
2989 Metaspace::~Metaspace() {
2990   delete _vsm;
2991   if (using_class_space()) {
2992     delete _class_vsm;
2993   }
2994 }
2995 
2996 VirtualSpaceList* Metaspace::_space_list = NULL;
2997 VirtualSpaceList* Metaspace::_class_space_list = NULL;
2998 
2999 ChunkManager* Metaspace::_chunk_manager_metadata = NULL;
3000 ChunkManager* Metaspace::_chunk_manager_class = NULL;
3001 
3002 #define VIRTUALSPACEMULTIPLIER 2
3003 
3004 #ifdef _LP64
3005 static const uint64_t UnscaledClassSpaceMax = (uint64_t(max_juint) + 1);
3006 
3007 void Metaspace::set_narrow_klass_base_and_shift(address metaspace_base, address cds_base) {
3008   // Figure out the narrow_klass_base and the narrow_klass_shift.  The
3009   // narrow_klass_base is the lower of the metaspace base and the cds base
3010   // (if cds is enabled).  The narrow_klass_shift depends on the distance
3011   // between the lower base and higher address.
3012   address lower_base;
3013   address higher_address;
3014 #if INCLUDE_CDS
3015   if (UseSharedSpaces) {
3016     higher_address = MAX2((address)(cds_base + FileMapInfo::shared_spaces_size()),
3017                           (address)(metaspace_base + compressed_class_space_size()));
3018     lower_base = MIN2(metaspace_base, cds_base);
3019   } else
3020 #endif
3021   {
3022     higher_address = metaspace_base + compressed_class_space_size();
3023     lower_base = metaspace_base;
3024 
3025     uint64_t klass_encoding_max = UnscaledClassSpaceMax << LogKlassAlignmentInBytes;
3026     // If compressed class space fits in lower 32G, we don't need a base.
3027     if (higher_address <= (address)klass_encoding_max) {
3028       lower_base = 0; // effectively lower base is zero.
3029     }
3030   }
3031 
3032   Universe::set_narrow_klass_base(lower_base);
3033 
3034   if ((uint64_t)(higher_address - lower_base) <= UnscaledClassSpaceMax) {
3035     Universe::set_narrow_klass_shift(0);
3036   } else {
3037     assert(!UseSharedSpaces, "Cannot shift with UseSharedSpaces");
3038     Universe::set_narrow_klass_shift(LogKlassAlignmentInBytes);
3039   }
3040 }
3041 
3042 #if INCLUDE_CDS
3043 // Return TRUE if the specified metaspace_base and cds_base are close enough
3044 // to work with compressed klass pointers.
3045 bool Metaspace::can_use_cds_with_metaspace_addr(char* metaspace_base, address cds_base) {
3046   assert(cds_base != 0 && UseSharedSpaces, "Only use with CDS");
3047   assert(UseCompressedClassPointers, "Only use with CompressedKlassPtrs");
3048   address lower_base = MIN2((address)metaspace_base, cds_base);
3049   address higher_address = MAX2((address)(cds_base + FileMapInfo::shared_spaces_size()),
3050                                 (address)(metaspace_base + compressed_class_space_size()));
3051   return ((uint64_t)(higher_address - lower_base) <= UnscaledClassSpaceMax);
3052 }
3053 #endif
3054 
3055 // Try to allocate the metaspace at the requested addr.
3056 void Metaspace::allocate_metaspace_compressed_klass_ptrs(char* requested_addr, address cds_base) {
3057   assert(using_class_space(), "called improperly");
3058   assert(UseCompressedClassPointers, "Only use with CompressedKlassPtrs");
3059   assert(compressed_class_space_size() < KlassEncodingMetaspaceMax,
3060          "Metaspace size is too big");
3061   assert_is_ptr_aligned(requested_addr, _reserve_alignment);
3062   assert_is_ptr_aligned(cds_base, _reserve_alignment);
3063   assert_is_size_aligned(compressed_class_space_size(), _reserve_alignment);
3064 
3065   // Don't use large pages for the class space.
3066   bool large_pages = false;
3067 
3068   ReservedSpace metaspace_rs = ReservedSpace(compressed_class_space_size(),
3069                                              _reserve_alignment,
3070                                              large_pages,
3071                                              requested_addr, 0);
3072   if (!metaspace_rs.is_reserved()) {
3073 #if INCLUDE_CDS
3074     if (UseSharedSpaces) {
3075       size_t increment = align_size_up(1*G, _reserve_alignment);
3076 
3077       // Keep trying to allocate the metaspace, increasing the requested_addr
3078       // by 1GB each time, until we reach an address that will no longer allow
3079       // use of CDS with compressed klass pointers.
3080       char *addr = requested_addr;
3081       while (!metaspace_rs.is_reserved() && (addr + increment > addr) &&
3082              can_use_cds_with_metaspace_addr(addr + increment, cds_base)) {
3083         addr = addr + increment;
3084         metaspace_rs = ReservedSpace(compressed_class_space_size(),
3085                                      _reserve_alignment, large_pages, addr, 0);
3086       }
3087     }
3088 #endif
3089     // If no successful allocation then try to allocate the space anywhere.  If
3090     // that fails then OOM doom.  At this point we cannot try allocating the
3091     // metaspace as if UseCompressedClassPointers is off because too much
3092     // initialization has happened that depends on UseCompressedClassPointers.
3093     // So, UseCompressedClassPointers cannot be turned off at this point.
3094     if (!metaspace_rs.is_reserved()) {
3095       metaspace_rs = ReservedSpace(compressed_class_space_size(),
3096                                    _reserve_alignment, large_pages);
3097       if (!metaspace_rs.is_reserved()) {
3098         vm_exit_during_initialization(err_msg("Could not allocate metaspace: %d bytes",
3099                                               compressed_class_space_size()));
3100       }
3101     }
3102   }
3103 
3104   // If we got here then the metaspace got allocated.
3105   MemTracker::record_virtual_memory_type((address)metaspace_rs.base(), mtClass);
3106 
3107 #if INCLUDE_CDS
3108   // Verify that we can use shared spaces.  Otherwise, turn off CDS.
3109   if (UseSharedSpaces && !can_use_cds_with_metaspace_addr(metaspace_rs.base(), cds_base)) {
3110     FileMapInfo::stop_sharing_and_unmap(
3111         "Could not allocate metaspace at a compatible address");
3112   }
3113 #endif
3114   set_narrow_klass_base_and_shift((address)metaspace_rs.base(),
3115                                   UseSharedSpaces ? (address)cds_base : 0);
3116 
3117   initialize_class_space(metaspace_rs);
3118 
3119   if (PrintCompressedOopsMode || (PrintMiscellaneous && Verbose)) {
3120       print_compressed_class_space(gclog_or_tty, requested_addr);
3121   }
3122 }
3123 
3124 void Metaspace::print_compressed_class_space(outputStream* st, const char* requested_addr) {
3125   st->print_cr("Narrow klass base: " PTR_FORMAT ", Narrow klass shift: %d",
3126                p2i(Universe::narrow_klass_base()), Universe::narrow_klass_shift());
3127   if (_class_space_list != NULL) {
3128     address base = (address)_class_space_list->current_virtual_space()->bottom();
3129     st->print("Compressed class space size: " SIZE_FORMAT " Address: " PTR_FORMAT,
3130                  compressed_class_space_size(), p2i(base));
3131     if (requested_addr != 0) {
3132       st->print(" Req Addr: " PTR_FORMAT, p2i(requested_addr));
3133     }
3134     st->cr();
3135    }
3136  }
3137 
3138 // For UseCompressedClassPointers the class space is reserved above the top of
3139 // the Java heap.  The argument passed in is at the base of the compressed space.
3140 void Metaspace::initialize_class_space(ReservedSpace rs) {
3141   // The reserved space size may be bigger because of alignment, esp with UseLargePages
3142   assert(rs.size() >= CompressedClassSpaceSize,
3143          err_msg(SIZE_FORMAT " != " UINTX_FORMAT, rs.size(), CompressedClassSpaceSize));
3144   assert(using_class_space(), "Must be using class space");
3145   _class_space_list = new VirtualSpaceList(rs);
3146   _chunk_manager_class = new ChunkManager(ClassSpecializedChunk, ClassSmallChunk, ClassMediumChunk);
3147 
3148   if (!_class_space_list->initialization_succeeded()) {
3149     vm_exit_during_initialization("Failed to setup compressed class space virtual space list.");
3150   }
3151 }
3152 
3153 #endif
3154 
3155 void Metaspace::ergo_initialize() {
3156   if (DumpSharedSpaces) {
3157     // Using large pages when dumping the shared archive is currently not implemented.
3158     FLAG_SET_ERGO(bool, UseLargePagesInMetaspace, false);
3159   }
3160 
3161   size_t page_size = os::vm_page_size();
3162   if (UseLargePages && UseLargePagesInMetaspace) {
3163     page_size = os::large_page_size();
3164   }
3165 
3166   _commit_alignment  = page_size;
3167   _reserve_alignment = MAX2(page_size, (size_t)os::vm_allocation_granularity());
3168 
3169   // Do not use FLAG_SET_ERGO to update MaxMetaspaceSize, since this will
3170   // override if MaxMetaspaceSize was set on the command line or not.
3171   // This information is needed later to conform to the specification of the
3172   // java.lang.management.MemoryUsage API.
3173   //
3174   // Ideally, we would be able to set the default value of MaxMetaspaceSize in
3175   // globals.hpp to the aligned value, but this is not possible, since the
3176   // alignment depends on other flags being parsed.
3177   MaxMetaspaceSize = align_size_down_bounded(MaxMetaspaceSize, _reserve_alignment);
3178 
3179   if (MetaspaceSize > MaxMetaspaceSize) {
3180     MetaspaceSize = MaxMetaspaceSize;
3181   }
3182 
3183   MetaspaceSize = align_size_down_bounded(MetaspaceSize, _commit_alignment);
3184 
3185   assert(MetaspaceSize <= MaxMetaspaceSize, "MetaspaceSize should be limited by MaxMetaspaceSize");
3186 
3187   if (MetaspaceSize < 256*K) {
3188     vm_exit_during_initialization("Too small initial Metaspace size");
3189   }
3190 
3191   MinMetaspaceExpansion = align_size_down_bounded(MinMetaspaceExpansion, _commit_alignment);
3192   MaxMetaspaceExpansion = align_size_down_bounded(MaxMetaspaceExpansion, _commit_alignment);
3193 
3194   CompressedClassSpaceSize = align_size_down_bounded(CompressedClassSpaceSize, _reserve_alignment);
3195   set_compressed_class_space_size(CompressedClassSpaceSize);
3196 
3197   // Initial virtual space size will be calculated at global_initialize()
3198   uintx min_metaspace_sz =
3199       VIRTUALSPACEMULTIPLIER * InitialBootClassLoaderMetaspaceSize;
3200   if (UseCompressedClassPointers) {
3201     if ((min_metaspace_sz + CompressedClassSpaceSize) >  MaxMetaspaceSize) {
3202       if (min_metaspace_sz >= MaxMetaspaceSize) {
3203         vm_exit_during_initialization("MaxMetaspaceSize is too small.");
3204       } else {
3205         FLAG_SET_ERGO(uintx, CompressedClassSpaceSize,
3206                       MaxMetaspaceSize - min_metaspace_sz);
3207       }
3208     }
3209   } else if (min_metaspace_sz >= MaxMetaspaceSize) {
3210     FLAG_SET_ERGO(uintx, InitialBootClassLoaderMetaspaceSize,
3211                   min_metaspace_sz);
3212   }
3213 
3214 }
3215 
3216 void Metaspace::global_initialize() {
3217   MetaspaceGC::initialize();
3218 
3219   // Initialize the alignment for shared spaces.
3220   int max_alignment = os::vm_allocation_granularity();
3221   size_t cds_total = 0;
3222 
3223   MetaspaceShared::set_max_alignment(max_alignment);
3224 
3225   if (DumpSharedSpaces) {
3226 #if INCLUDE_CDS
3227     MetaspaceShared::estimate_regions_size();
3228 
3229     SharedReadOnlySize  = align_size_up(SharedReadOnlySize,  max_alignment);
3230     SharedReadWriteSize = align_size_up(SharedReadWriteSize, max_alignment);
3231     SharedMiscDataSize  = align_size_up(SharedMiscDataSize,  max_alignment);
3232     SharedMiscCodeSize  = align_size_up(SharedMiscCodeSize,  max_alignment);
3233 
3234     // the min_misc_code_size estimate is based on MetaspaceShared::generate_vtable_methods()
3235     uintx min_misc_code_size = align_size_up(
3236       (MetaspaceShared::num_virtuals * MetaspaceShared::vtbl_list_size) *
3237         (sizeof(void*) + MetaspaceShared::vtbl_method_size) + MetaspaceShared::vtbl_common_code_size,
3238           max_alignment);
3239 
3240     if (SharedMiscCodeSize < min_misc_code_size) {
3241       report_out_of_shared_space(SharedMiscCode);
3242     }
3243 
3244     // Initialize with the sum of the shared space sizes.  The read-only
3245     // and read write metaspace chunks will be allocated out of this and the
3246     // remainder is the misc code and data chunks.
3247     cds_total = FileMapInfo::shared_spaces_size();
3248     cds_total = align_size_up(cds_total, _reserve_alignment);
3249     _space_list = new VirtualSpaceList(cds_total/wordSize);
3250     _chunk_manager_metadata = new ChunkManager(SpecializedChunk, SmallChunk, MediumChunk);
3251 
3252     if (!_space_list->initialization_succeeded()) {
3253       vm_exit_during_initialization("Unable to dump shared archive.", NULL);
3254     }
3255 
3256 #ifdef _LP64
3257     if (cds_total + compressed_class_space_size() > UnscaledClassSpaceMax) {
3258       vm_exit_during_initialization("Unable to dump shared archive.",
3259           err_msg("Size of archive (" SIZE_FORMAT ") + compressed class space ("
3260                   SIZE_FORMAT ") == total (" SIZE_FORMAT ") is larger than compressed "
3261                   "klass limit: " SIZE_FORMAT, cds_total, compressed_class_space_size(),
3262                   cds_total + compressed_class_space_size(), UnscaledClassSpaceMax));
3263     }
3264 
3265     // Set the compressed klass pointer base so that decoding of these pointers works
3266     // properly when creating the shared archive.
3267     assert(UseCompressedOops && UseCompressedClassPointers,
3268       "UseCompressedOops and UseCompressedClassPointers must be set");
3269     Universe::set_narrow_klass_base((address)_space_list->current_virtual_space()->bottom());
3270     if (TraceMetavirtualspaceAllocation && Verbose) {
3271       gclog_or_tty->print_cr("Setting_narrow_klass_base to Address: " PTR_FORMAT,
3272                              _space_list->current_virtual_space()->bottom());
3273     }
3274 
3275     Universe::set_narrow_klass_shift(0);
3276 #endif // _LP64
3277 #endif // INCLUDE_CDS
3278   } else {
3279 #if INCLUDE_CDS
3280     // If using shared space, open the file that contains the shared space
3281     // and map in the memory before initializing the rest of metaspace (so
3282     // the addresses don't conflict)
3283     address cds_address = NULL;
3284     if (UseSharedSpaces) {
3285       FileMapInfo* mapinfo = new FileMapInfo();
3286 
3287       // Open the shared archive file, read and validate the header. If
3288       // initialization fails, shared spaces [UseSharedSpaces] are
3289       // disabled and the file is closed.
3290       // Map in spaces now also
3291       if (mapinfo->initialize() && MetaspaceShared::map_shared_spaces(mapinfo)) {
3292         cds_total = FileMapInfo::shared_spaces_size();
3293         cds_address = (address)mapinfo->region_base(0);
3294       } else {
3295         assert(!mapinfo->is_open() && !UseSharedSpaces,
3296                "archive file not closed or shared spaces not disabled.");
3297       }
3298     }
3299 #endif // INCLUDE_CDS
3300 #ifdef _LP64
3301     // If UseCompressedClassPointers is set then allocate the metaspace area
3302     // above the heap and above the CDS area (if it exists).
3303     if (using_class_space()) {
3304       if (UseSharedSpaces) {
3305 #if INCLUDE_CDS
3306         char* cds_end = (char*)(cds_address + cds_total);
3307         cds_end = (char *)align_ptr_up(cds_end, _reserve_alignment);
3308         allocate_metaspace_compressed_klass_ptrs(cds_end, cds_address);
3309 #endif
3310       } else {
3311         char* base = (char*)align_ptr_up(Universe::heap()->reserved_region().end(), _reserve_alignment);
3312         allocate_metaspace_compressed_klass_ptrs(base, 0);
3313       }
3314     }
3315 #endif // _LP64
3316 
3317     // Initialize these before initializing the VirtualSpaceList
3318     _first_chunk_word_size = InitialBootClassLoaderMetaspaceSize / BytesPerWord;
3319     _first_chunk_word_size = align_word_size_up(_first_chunk_word_size);
3320     // Make the first class chunk bigger than a medium chunk so it's not put
3321     // on the medium chunk list.   The next chunk will be small and progress
3322     // from there.  This size calculated by -version.
3323     _first_class_chunk_word_size = MIN2((size_t)MediumChunk*6,
3324                                        (CompressedClassSpaceSize/BytesPerWord)*2);
3325     _first_class_chunk_word_size = align_word_size_up(_first_class_chunk_word_size);
3326     // Arbitrarily set the initial virtual space to a multiple
3327     // of the boot class loader size.
3328     size_t word_size = VIRTUALSPACEMULTIPLIER * _first_chunk_word_size;
3329     word_size = align_size_up(word_size, Metaspace::reserve_alignment_words());
3330 
3331     // Initialize the list of virtual spaces.
3332     _space_list = new VirtualSpaceList(word_size);
3333     _chunk_manager_metadata = new ChunkManager(SpecializedChunk, SmallChunk, MediumChunk);
3334 
3335     if (!_space_list->initialization_succeeded()) {
3336       vm_exit_during_initialization("Unable to setup metadata virtual space list.", NULL);
3337     }
3338   }
3339 
3340   _tracer = new MetaspaceTracer();
3341 }
3342 
3343 void Metaspace::post_initialize() {
3344   MetaspaceGC::post_initialize();
3345 }
3346 
3347 void Metaspace::initialize_first_chunk(MetaspaceType type, MetadataType mdtype) {
3348   Metachunk* chunk = get_initialization_chunk(type, mdtype);
3349   if (chunk != NULL) {
3350     // Add to this manager's list of chunks in use and current_chunk().
3351     get_space_manager(mdtype)->add_chunk(chunk, true);
3352   }
3353 }
3354 
3355 Metachunk* Metaspace::get_initialization_chunk(MetaspaceType type, MetadataType mdtype) {
3356   size_t chunk_word_size = get_space_manager(mdtype)->get_initial_chunk_size(type);
3357 
3358   // Get a chunk from the chunk freelist
3359   Metachunk* chunk = get_chunk_manager(mdtype)->chunk_freelist_allocate(chunk_word_size);
3360 
3361   if (chunk == NULL) {
3362     chunk = get_space_list(mdtype)->get_new_chunk(chunk_word_size,
3363                                                   get_space_manager(mdtype)->medium_chunk_bunch());
3364   }
3365 
3366   // For dumping shared archive, report error if allocation has failed.
3367   if (DumpSharedSpaces && chunk == NULL) {
3368     report_insufficient_metaspace(MetaspaceAux::committed_bytes() + chunk_word_size * BytesPerWord);
3369   }
3370 
3371   return chunk;
3372 }
3373 
3374 void Metaspace::verify_global_initialization() {
3375   assert(space_list() != NULL, "Metadata VirtualSpaceList has not been initialized");
3376   assert(chunk_manager_metadata() != NULL, "Metadata ChunkManager has not been initialized");
3377 
3378   if (using_class_space()) {
3379     assert(class_space_list() != NULL, "Class VirtualSpaceList has not been initialized");
3380     assert(chunk_manager_class() != NULL, "Class ChunkManager has not been initialized");
3381   }
3382 }
3383 
3384 void Metaspace::initialize(Mutex* lock, MetaspaceType type) {
3385   verify_global_initialization();
3386 
3387   // Allocate SpaceManager for metadata objects.
3388   _vsm = new SpaceManager(NonClassType, lock);
3389 
3390   if (using_class_space()) {
3391     // Allocate SpaceManager for classes.
3392     _class_vsm = new SpaceManager(ClassType, lock);
3393   }
3394 
3395   MutexLockerEx cl(SpaceManager::expand_lock(), Mutex::_no_safepoint_check_flag);
3396 
3397   // Allocate chunk for metadata objects
3398   initialize_first_chunk(type, NonClassType);
3399 
3400   // Allocate chunk for class metadata objects
3401   if (using_class_space()) {
3402     initialize_first_chunk(type, ClassType);
3403   }
3404 
3405   _alloc_record_head = NULL;
3406   _alloc_record_tail = NULL;
3407 }
3408 
3409 size_t Metaspace::align_word_size_up(size_t word_size) {
3410   size_t byte_size = word_size * wordSize;
3411   return ReservedSpace::allocation_align_size_up(byte_size) / wordSize;
3412 }
3413 
3414 MetaWord* Metaspace::allocate(size_t word_size, MetadataType mdtype) {
3415   // DumpSharedSpaces doesn't use class metadata area (yet)
3416   // Also, don't use class_vsm() unless UseCompressedClassPointers is true.
3417   if (is_class_space_allocation(mdtype)) {
3418     return  class_vsm()->allocate(word_size);
3419   } else {
3420     return  vsm()->allocate(word_size);
3421   }
3422 }
3423 
3424 MetaWord* Metaspace::expand_and_allocate(size_t word_size, MetadataType mdtype) {
3425   size_t delta_bytes = MetaspaceGC::delta_capacity_until_GC(word_size * BytesPerWord);
3426   assert(delta_bytes > 0, "Must be");
3427 
3428   size_t before = 0;
3429   size_t after = 0;
3430   bool can_retry = true;
3431   MetaWord* res;
3432   bool incremented;
3433 
3434   // Each thread increments the HWM at most once. Even if the thread fails to increment
3435   // the HWM, an allocation is still attempted. This is because another thread must then
3436   // have incremented the HWM and therefore the allocation might still succeed.
3437   do {
3438     incremented = MetaspaceGC::inc_capacity_until_GC(delta_bytes, &after, &before, &can_retry);
3439     res = allocate(word_size, mdtype);
3440   } while (!incremented && res == NULL && can_retry);
3441 
3442   if (incremented) {
3443     tracer()->report_gc_threshold(before, after,
3444                                   MetaspaceGCThresholdUpdater::ExpandAndAllocate);
3445     if (PrintGCDetails && Verbose) {
3446       gclog_or_tty->print_cr("Increase capacity to GC from " SIZE_FORMAT
3447           " to " SIZE_FORMAT, before, after);
3448     }
3449   }
3450 
3451   return res;
3452 }
3453 
3454 // Space allocated in the Metaspace.  This may
3455 // be across several metadata virtual spaces.
3456 char* Metaspace::bottom() const {
3457   assert(DumpSharedSpaces, "only useful and valid for dumping shared spaces");
3458   return (char*)vsm()->current_chunk()->bottom();
3459 }
3460 
3461 size_t Metaspace::used_words_slow(MetadataType mdtype) const {
3462   if (mdtype == ClassType) {
3463     return using_class_space() ? class_vsm()->sum_used_in_chunks_in_use() : 0;
3464   } else {
3465     return vsm()->sum_used_in_chunks_in_use();  // includes overhead!
3466   }
3467 }
3468 
3469 size_t Metaspace::free_words_slow(MetadataType mdtype) const {
3470   if (mdtype == ClassType) {
3471     return using_class_space() ? class_vsm()->sum_free_in_chunks_in_use() : 0;
3472   } else {
3473     return vsm()->sum_free_in_chunks_in_use();
3474   }
3475 }
3476 
3477 // Space capacity in the Metaspace.  It includes
3478 // space in the list of chunks from which allocations
3479 // have been made. Don't include space in the global freelist and
3480 // in the space available in the dictionary which
3481 // is already counted in some chunk.
3482 size_t Metaspace::capacity_words_slow(MetadataType mdtype) const {
3483   if (mdtype == ClassType) {
3484     return using_class_space() ? class_vsm()->sum_capacity_in_chunks_in_use() : 0;
3485   } else {
3486     return vsm()->sum_capacity_in_chunks_in_use();
3487   }
3488 }
3489 
3490 size_t Metaspace::used_bytes_slow(MetadataType mdtype) const {
3491   return used_words_slow(mdtype) * BytesPerWord;
3492 }
3493 
3494 size_t Metaspace::capacity_bytes_slow(MetadataType mdtype) const {
3495   return capacity_words_slow(mdtype) * BytesPerWord;
3496 }
3497 
3498 size_t Metaspace::allocated_blocks_bytes() const {
3499   return vsm()->allocated_blocks_bytes() +
3500       (using_class_space() ? class_vsm()->allocated_blocks_bytes() : 0);
3501 }
3502 
3503 size_t Metaspace::allocated_chunks_bytes() const {
3504   return vsm()->allocated_chunks_bytes() +
3505       (using_class_space() ? class_vsm()->allocated_chunks_bytes() : 0);
3506 }
3507 
3508 void Metaspace::deallocate(MetaWord* ptr, size_t word_size, bool is_class) {
3509   if (SafepointSynchronize::is_at_safepoint()) {
3510     if (DumpSharedSpaces && PrintSharedSpaces) {
3511       record_deallocation(ptr, vsm()->get_raw_word_size(word_size));
3512     }
3513 
3514     assert(Thread::current()->is_VM_thread(), "should be the VM thread");
3515     // Don't take Heap_lock
3516     MutexLockerEx ml(vsm()->lock(), Mutex::_no_safepoint_check_flag);
3517     if (word_size < TreeChunk<Metablock, FreeList<Metablock> >::min_size()) {
3518       // Dark matter.  Too small for dictionary.
3519 #ifdef ASSERT
3520       Copy::fill_to_words((HeapWord*)ptr, word_size, 0xf5f5f5f5);
3521 #endif
3522       return;
3523     }
3524     if (is_class && using_class_space()) {
3525       class_vsm()->deallocate(ptr, word_size);
3526     } else {
3527       vsm()->deallocate(ptr, word_size);
3528     }
3529   } else {
3530     MutexLockerEx ml(vsm()->lock(), Mutex::_no_safepoint_check_flag);
3531 
3532     if (word_size < TreeChunk<Metablock, FreeList<Metablock> >::min_size()) {
3533       // Dark matter.  Too small for dictionary.
3534 #ifdef ASSERT
3535       Copy::fill_to_words((HeapWord*)ptr, word_size, 0xf5f5f5f5);
3536 #endif
3537       return;
3538     }
3539     if (is_class && using_class_space()) {
3540       class_vsm()->deallocate(ptr, word_size);
3541     } else {
3542       vsm()->deallocate(ptr, word_size);
3543     }
3544   }
3545 }
3546 
3547 
3548 MetaWord* Metaspace::allocate(ClassLoaderData* loader_data, size_t word_size,
3549                               bool read_only, MetaspaceObj::Type type, TRAPS) {
3550   if (HAS_PENDING_EXCEPTION) {
3551     assert(false, "Should not allocate with exception pending");
3552     return NULL;  // caller does a CHECK_NULL too
3553   }
3554 
3555   assert(loader_data != NULL, "Should never pass around a NULL loader_data. "
3556         "ClassLoaderData::the_null_class_loader_data() should have been used.");
3557 
3558   // Allocate in metaspaces without taking out a lock, because it deadlocks
3559   // with the SymbolTable_lock.  Dumping is single threaded for now.  We'll have
3560   // to revisit this for application class data sharing.
3561   if (DumpSharedSpaces) {
3562     assert(type > MetaspaceObj::UnknownType && type < MetaspaceObj::_number_of_types, "sanity");
3563     Metaspace* space = read_only ? loader_data->ro_metaspace() : loader_data->rw_metaspace();
3564     MetaWord* result = space->allocate(word_size, NonClassType);
3565     if (result == NULL) {
3566       report_out_of_shared_space(read_only ? SharedReadOnly : SharedReadWrite);
3567     }
3568     if (PrintSharedSpaces) {
3569       space->record_allocation(result, type, space->vsm()->get_raw_word_size(word_size));
3570     }
3571 
3572     // Zero initialize.
3573     Copy::fill_to_aligned_words((HeapWord*)result, word_size, 0);
3574 
3575     return result;
3576   }
3577 
3578   MetadataType mdtype = (type == MetaspaceObj::ClassType) ? ClassType : NonClassType;
3579 
3580   // Try to allocate metadata.
3581   MetaWord* result = loader_data->metaspace_non_null()->allocate(word_size, mdtype);
3582 
3583   if (result == NULL) {
3584     tracer()->report_metaspace_allocation_failure(loader_data, word_size, type, mdtype);
3585 
3586     // Allocation failed.
3587     if (is_init_completed()) {
3588       // Only start a GC if the bootstrapping has completed.
3589 
3590       // Try to clean out some memory and retry.
3591       result = Universe::heap()->collector_policy()->satisfy_failed_metadata_allocation(
3592           loader_data, word_size, mdtype);
3593     }
3594   }
3595 
3596   if (result == NULL) {
3597     report_metadata_oome(loader_data, word_size, type, mdtype, CHECK_NULL);
3598   }
3599 
3600   // Zero initialize.
3601   Copy::fill_to_aligned_words((HeapWord*)result, word_size, 0);
3602 
3603   return result;
3604 }
3605 
3606 size_t Metaspace::class_chunk_size(size_t word_size) {
3607   assert(using_class_space(), "Has to use class space");
3608   return class_vsm()->calc_chunk_size(word_size);
3609 }
3610 
3611 void Metaspace::report_metadata_oome(ClassLoaderData* loader_data, size_t word_size, MetaspaceObj::Type type, MetadataType mdtype, TRAPS) {
3612   tracer()->report_metadata_oom(loader_data, word_size, type, mdtype);
3613 
3614   // If result is still null, we are out of memory.
3615   if (Verbose && TraceMetadataChunkAllocation) {
3616     gclog_or_tty->print_cr("Metaspace allocation failed for size "
3617         SIZE_FORMAT, word_size);
3618     if (loader_data->metaspace_or_null() != NULL) {
3619       loader_data->dump(gclog_or_tty);
3620     }
3621     MetaspaceAux::dump(gclog_or_tty);
3622   }
3623 
3624   bool out_of_compressed_class_space = false;
3625   if (is_class_space_allocation(mdtype)) {
3626     Metaspace* metaspace = loader_data->metaspace_non_null();
3627     out_of_compressed_class_space =
3628       MetaspaceAux::committed_bytes(Metaspace::ClassType) +
3629       (metaspace->class_chunk_size(word_size) * BytesPerWord) >
3630       CompressedClassSpaceSize;
3631   }
3632 
3633   // -XX:+HeapDumpOnOutOfMemoryError and -XX:OnOutOfMemoryError support
3634   const char* space_string = out_of_compressed_class_space ?
3635     "Compressed class space" : "Metaspace";
3636 
3637   report_java_out_of_memory(space_string);
3638 
3639   if (JvmtiExport::should_post_resource_exhausted()) {
3640     JvmtiExport::post_resource_exhausted(
3641         JVMTI_RESOURCE_EXHAUSTED_OOM_ERROR,
3642         space_string);
3643   }
3644 
3645   if (!is_init_completed()) {
3646     vm_exit_during_initialization("OutOfMemoryError", space_string);
3647   }
3648 
3649   if (out_of_compressed_class_space) {
3650     THROW_OOP(Universe::out_of_memory_error_class_metaspace());
3651   } else {
3652     THROW_OOP(Universe::out_of_memory_error_metaspace());
3653   }
3654 }
3655 
3656 const char* Metaspace::metadata_type_name(Metaspace::MetadataType mdtype) {
3657   switch (mdtype) {
3658     case Metaspace::ClassType: return "Class";
3659     case Metaspace::NonClassType: return "Metadata";
3660     default:
3661       assert(false, err_msg("Got bad mdtype: %d", (int) mdtype));
3662       return NULL;
3663   }
3664 }
3665 
3666 void Metaspace::record_allocation(void* ptr, MetaspaceObj::Type type, size_t word_size) {
3667   assert(DumpSharedSpaces, "sanity");
3668 
3669   int byte_size = (int)word_size * HeapWordSize;
3670   AllocRecord *rec = new AllocRecord((address)ptr, type, byte_size);
3671 
3672   if (_alloc_record_head == NULL) {
3673     _alloc_record_head = _alloc_record_tail = rec;
3674   } else if (_alloc_record_tail->_ptr + _alloc_record_tail->_byte_size == (address)ptr) {
3675     _alloc_record_tail->_next = rec;
3676     _alloc_record_tail = rec;
3677   } else {
3678     // slow linear search, but this doesn't happen that often, and only when dumping
3679     for (AllocRecord *old = _alloc_record_head; old; old = old->_next) {
3680       if (old->_ptr == ptr) {
3681         assert(old->_type == MetaspaceObj::DeallocatedType, "sanity");
3682         int remain_bytes = old->_byte_size - byte_size;
3683         assert(remain_bytes >= 0, "sanity");
3684         old->_type = type;
3685 
3686         if (remain_bytes == 0) {
3687           delete(rec);
3688         } else {
3689           address remain_ptr = address(ptr) + byte_size;
3690           rec->_ptr = remain_ptr;
3691           rec->_byte_size = remain_bytes;
3692           rec->_type = MetaspaceObj::DeallocatedType;
3693           rec->_next = old->_next;
3694           old->_byte_size = byte_size;
3695           old->_next = rec;
3696         }
3697         return;
3698       }
3699     }
3700     assert(0, "reallocating a freed pointer that was not recorded");
3701   }
3702 }
3703 
3704 void Metaspace::record_deallocation(void* ptr, size_t word_size) {
3705   assert(DumpSharedSpaces, "sanity");
3706 
3707   for (AllocRecord *rec = _alloc_record_head; rec; rec = rec->_next) {
3708     if (rec->_ptr == ptr) {
3709       assert(rec->_byte_size == (int)word_size * HeapWordSize, "sanity");
3710       rec->_type = MetaspaceObj::DeallocatedType;
3711       return;
3712     }
3713   }
3714 
3715   assert(0, "deallocating a pointer that was not recorded");
3716 }
3717 
3718 void Metaspace::iterate(Metaspace::AllocRecordClosure *closure) {
3719   assert(DumpSharedSpaces, "unimplemented for !DumpSharedSpaces");
3720 
3721   address last_addr = (address)bottom();
3722 
3723   for (AllocRecord *rec = _alloc_record_head; rec; rec = rec->_next) {
3724     address ptr = rec->_ptr;
3725     if (last_addr < ptr) {
3726       closure->doit(last_addr, MetaspaceObj::UnknownType, ptr - last_addr);
3727     }
3728     closure->doit(ptr, rec->_type, rec->_byte_size);
3729     last_addr = ptr + rec->_byte_size;
3730   }
3731 
3732   address top = ((address)bottom()) + used_bytes_slow(Metaspace::NonClassType);
3733   if (last_addr < top) {
3734     closure->doit(last_addr, MetaspaceObj::UnknownType, top - last_addr);
3735   }
3736 }
3737 
3738 void Metaspace::purge(MetadataType mdtype) {
3739   get_space_list(mdtype)->purge(get_chunk_manager(mdtype));
3740 }
3741 
3742 void Metaspace::purge() {
3743   MutexLockerEx cl(SpaceManager::expand_lock(),
3744                    Mutex::_no_safepoint_check_flag);
3745   purge(NonClassType);
3746   if (using_class_space()) {
3747     purge(ClassType);
3748   }
3749 }
3750 
3751 void Metaspace::print_on(outputStream* out) const {
3752   // Print both class virtual space counts and metaspace.
3753   if (Verbose) {
3754     vsm()->print_on(out);
3755     if (using_class_space()) {
3756       class_vsm()->print_on(out);
3757     }
3758   }
3759 }
3760 
3761 bool Metaspace::contains(const void* ptr) {
3762   if (UseSharedSpaces && MetaspaceShared::is_in_shared_space(ptr)) {
3763     return true;
3764   }
3765 
3766   if (using_class_space() && get_space_list(ClassType)->contains(ptr)) {
3767      return true;
3768   }
3769 
3770   return get_space_list(NonClassType)->contains(ptr);
3771 }
3772 
3773 void Metaspace::verify() {
3774   vsm()->verify();
3775   if (using_class_space()) {
3776     class_vsm()->verify();
3777   }
3778 }
3779 
3780 void Metaspace::dump(outputStream* const out) const {
3781   out->print_cr("\nVirtual space manager: " INTPTR_FORMAT, vsm());
3782   vsm()->dump(out);
3783   if (using_class_space()) {
3784     out->print_cr("\nClass space manager: " INTPTR_FORMAT, class_vsm());
3785     class_vsm()->dump(out);
3786   }
3787 }
3788 
3789 /////////////// Unit tests ///////////////
3790 
3791 #ifndef PRODUCT
3792 
3793 class TestMetaspaceAuxTest : AllStatic {
3794  public:
3795   static void test_reserved() {
3796     size_t reserved = MetaspaceAux::reserved_bytes();
3797 
3798     assert(reserved > 0, "assert");
3799 
3800     size_t committed  = MetaspaceAux::committed_bytes();
3801     assert(committed <= reserved, "assert");
3802 
3803     size_t reserved_metadata = MetaspaceAux::reserved_bytes(Metaspace::NonClassType);
3804     assert(reserved_metadata > 0, "assert");
3805     assert(reserved_metadata <= reserved, "assert");
3806 
3807     if (UseCompressedClassPointers) {
3808       size_t reserved_class    = MetaspaceAux::reserved_bytes(Metaspace::ClassType);
3809       assert(reserved_class > 0, "assert");
3810       assert(reserved_class < reserved, "assert");
3811     }
3812   }
3813 
3814   static void test_committed() {
3815     size_t committed = MetaspaceAux::committed_bytes();
3816 
3817     assert(committed > 0, "assert");
3818 
3819     size_t reserved  = MetaspaceAux::reserved_bytes();
3820     assert(committed <= reserved, "assert");
3821 
3822     size_t committed_metadata = MetaspaceAux::committed_bytes(Metaspace::NonClassType);
3823     assert(committed_metadata > 0, "assert");
3824     assert(committed_metadata <= committed, "assert");
3825 
3826     if (UseCompressedClassPointers) {
3827       size_t committed_class    = MetaspaceAux::committed_bytes(Metaspace::ClassType);
3828       assert(committed_class > 0, "assert");
3829       assert(committed_class < committed, "assert");
3830     }
3831   }
3832 
3833   static void test_virtual_space_list_large_chunk() {
3834     VirtualSpaceList* vs_list = new VirtualSpaceList(os::vm_allocation_granularity());
3835     MutexLockerEx cl(SpaceManager::expand_lock(), Mutex::_no_safepoint_check_flag);
3836     // A size larger than VirtualSpaceSize (256k) and add one page to make it _not_ be
3837     // vm_allocation_granularity aligned on Windows.
3838     size_t large_size = (size_t)(2*256*K + (os::vm_page_size()/BytesPerWord));
3839     large_size += (os::vm_page_size()/BytesPerWord);
3840     vs_list->get_new_chunk(large_size, 0);
3841   }
3842 
3843   static void test() {
3844     test_reserved();
3845     test_committed();
3846     test_virtual_space_list_large_chunk();
3847   }
3848 };
3849 
3850 void TestMetaspaceAux_test() {
3851   TestMetaspaceAuxTest::test();
3852 }
3853 
3854 class TestVirtualSpaceNodeTest {
3855   static void chunk_up(size_t words_left, size_t& num_medium_chunks,
3856                                           size_t& num_small_chunks,
3857                                           size_t& num_specialized_chunks) {
3858     num_medium_chunks = words_left / MediumChunk;
3859     words_left = words_left % MediumChunk;
3860 
3861     num_small_chunks = words_left / SmallChunk;
3862     words_left = words_left % SmallChunk;
3863     // how many specialized chunks can we get?
3864     num_specialized_chunks = words_left / SpecializedChunk;
3865     assert(words_left % SpecializedChunk == 0, "should be nothing left");
3866   }
3867 
3868  public:
3869   static void test() {
3870     MutexLockerEx ml(SpaceManager::expand_lock(), Mutex::_no_safepoint_check_flag);
3871     const size_t vsn_test_size_words = MediumChunk  * 4;
3872     const size_t vsn_test_size_bytes = vsn_test_size_words * BytesPerWord;
3873 
3874     // The chunk sizes must be multiples of eachother, or this will fail
3875     STATIC_ASSERT(MediumChunk % SmallChunk == 0);
3876     STATIC_ASSERT(SmallChunk % SpecializedChunk == 0);
3877 
3878     { // No committed memory in VSN
3879       ChunkManager cm(SpecializedChunk, SmallChunk, MediumChunk);
3880       VirtualSpaceNode vsn(vsn_test_size_bytes);
3881       vsn.initialize();
3882       vsn.retire(&cm);
3883       assert(cm.sum_free_chunks_count() == 0, "did not commit any memory in the VSN");
3884     }
3885 
3886     { // All of VSN is committed, half is used by chunks
3887       ChunkManager cm(SpecializedChunk, SmallChunk, MediumChunk);
3888       VirtualSpaceNode vsn(vsn_test_size_bytes);
3889       vsn.initialize();
3890       vsn.expand_by(vsn_test_size_words, vsn_test_size_words);
3891       vsn.get_chunk_vs(MediumChunk);
3892       vsn.get_chunk_vs(MediumChunk);
3893       vsn.retire(&cm);
3894       assert(cm.sum_free_chunks_count() == 2, "should have been memory left for 2 medium chunks");
3895       assert(cm.sum_free_chunks() == 2*MediumChunk, "sizes should add up");
3896     }
3897 
3898     { // 4 pages of VSN is committed, some is used by chunks
3899       ChunkManager cm(SpecializedChunk, SmallChunk, MediumChunk);
3900       VirtualSpaceNode vsn(vsn_test_size_bytes);
3901       const size_t page_chunks = 4 * (size_t)os::vm_page_size() / BytesPerWord;
3902       assert(page_chunks < MediumChunk, "Test expects medium chunks to be at least 4*page_size");
3903       vsn.initialize();
3904       vsn.expand_by(page_chunks, page_chunks);
3905       vsn.get_chunk_vs(SmallChunk);
3906       vsn.get_chunk_vs(SpecializedChunk);
3907       vsn.retire(&cm);
3908 
3909       // committed - used = words left to retire
3910       const size_t words_left = page_chunks - SmallChunk - SpecializedChunk;
3911 
3912       size_t num_medium_chunks, num_small_chunks, num_spec_chunks;
3913       chunk_up(words_left, num_medium_chunks, num_small_chunks, num_spec_chunks);
3914 
3915       assert(num_medium_chunks == 0, "should not get any medium chunks");
3916       assert(cm.sum_free_chunks_count() == (num_small_chunks + num_spec_chunks), "should be space for 3 chunks");
3917       assert(cm.sum_free_chunks() == words_left, "sizes should add up");
3918     }
3919 
3920     { // Half of VSN is committed, a humongous chunk is used
3921       ChunkManager cm(SpecializedChunk, SmallChunk, MediumChunk);
3922       VirtualSpaceNode vsn(vsn_test_size_bytes);
3923       vsn.initialize();
3924       vsn.expand_by(MediumChunk * 2, MediumChunk * 2);
3925       vsn.get_chunk_vs(MediumChunk + SpecializedChunk); // Humongous chunks will be aligned up to MediumChunk + SpecializedChunk
3926       vsn.retire(&cm);
3927 
3928       const size_t words_left = MediumChunk * 2 - (MediumChunk + SpecializedChunk);
3929       size_t num_medium_chunks, num_small_chunks, num_spec_chunks;
3930       chunk_up(words_left, num_medium_chunks, num_small_chunks, num_spec_chunks);
3931 
3932       assert(num_medium_chunks == 0, "should not get any medium chunks");
3933       assert(cm.sum_free_chunks_count() == (num_small_chunks + num_spec_chunks), "should be space for 3 chunks");
3934       assert(cm.sum_free_chunks() == words_left, "sizes should add up");
3935     }
3936 
3937   }
3938 
3939 #define assert_is_available_positive(word_size) \
3940   assert(vsn.is_available(word_size), \
3941     err_msg(#word_size ": " PTR_FORMAT " bytes were not available in " \
3942             "VirtualSpaceNode [" PTR_FORMAT ", " PTR_FORMAT ")", \
3943             (uintptr_t)(word_size * BytesPerWord), vsn.bottom(), vsn.end()));
3944 
3945 #define assert_is_available_negative(word_size) \
3946   assert(!vsn.is_available(word_size), \
3947     err_msg(#word_size ": " PTR_FORMAT " bytes should not be available in " \
3948             "VirtualSpaceNode [" PTR_FORMAT ", " PTR_FORMAT ")", \
3949             (uintptr_t)(word_size * BytesPerWord), vsn.bottom(), vsn.end()));
3950 
3951   static void test_is_available_positive() {
3952     // Reserve some memory.
3953     VirtualSpaceNode vsn(os::vm_allocation_granularity());
3954     assert(vsn.initialize(), "Failed to setup VirtualSpaceNode");
3955 
3956     // Commit some memory.
3957     size_t commit_word_size = os::vm_allocation_granularity() / BytesPerWord;
3958     bool expanded = vsn.expand_by(commit_word_size, commit_word_size);
3959     assert(expanded, "Failed to commit");
3960 
3961     // Check that is_available accepts the committed size.
3962     assert_is_available_positive(commit_word_size);
3963 
3964     // Check that is_available accepts half the committed size.
3965     size_t expand_word_size = commit_word_size / 2;
3966     assert_is_available_positive(expand_word_size);
3967   }
3968 
3969   static void test_is_available_negative() {
3970     // Reserve some memory.
3971     VirtualSpaceNode vsn(os::vm_allocation_granularity());
3972     assert(vsn.initialize(), "Failed to setup VirtualSpaceNode");
3973 
3974     // Commit some memory.
3975     size_t commit_word_size = os::vm_allocation_granularity() / BytesPerWord;
3976     bool expanded = vsn.expand_by(commit_word_size, commit_word_size);
3977     assert(expanded, "Failed to commit");
3978 
3979     // Check that is_available doesn't accept a too large size.
3980     size_t two_times_commit_word_size = commit_word_size * 2;
3981     assert_is_available_negative(two_times_commit_word_size);
3982   }
3983 
3984   static void test_is_available_overflow() {
3985     // Reserve some memory.
3986     VirtualSpaceNode vsn(os::vm_allocation_granularity());
3987     assert(vsn.initialize(), "Failed to setup VirtualSpaceNode");
3988 
3989     // Commit some memory.
3990     size_t commit_word_size = os::vm_allocation_granularity() / BytesPerWord;
3991     bool expanded = vsn.expand_by(commit_word_size, commit_word_size);
3992     assert(expanded, "Failed to commit");
3993 
3994     // Calculate a size that will overflow the virtual space size.
3995     void* virtual_space_max = (void*)(uintptr_t)-1;
3996     size_t bottom_to_max = pointer_delta(virtual_space_max, vsn.bottom(), 1);
3997     size_t overflow_size = bottom_to_max + BytesPerWord;
3998     size_t overflow_word_size = overflow_size / BytesPerWord;
3999 
4000     // Check that is_available can handle the overflow.
4001     assert_is_available_negative(overflow_word_size);
4002   }
4003 
4004   static void test_is_available() {
4005     TestVirtualSpaceNodeTest::test_is_available_positive();
4006     TestVirtualSpaceNodeTest::test_is_available_negative();
4007     TestVirtualSpaceNodeTest::test_is_available_overflow();
4008   }
4009 };
4010 
4011 void TestVirtualSpaceNode_test() {
4012   TestVirtualSpaceNodeTest::test();
4013   TestVirtualSpaceNodeTest::test_is_available();
4014 }
4015 
4016 // The following test is placed here instead of a gtest / unittest file
4017 // because the ChunkManager class is only available in this file.
4018 class SpaceManagerTest : AllStatic {
4019   friend void SpaceManager_test_adjust_initial_chunk_size();
4020 
4021   static void test_adjust_initial_chunk_size(bool is_class) {
4022     const size_t smallest = SpaceManager::smallest_chunk_size(is_class);
4023     const size_t normal   = SpaceManager::small_chunk_size(is_class);
4024     const size_t medium   = SpaceManager::medium_chunk_size(is_class);
4025 
4026 #define test_adjust_initial_chunk_size(value, expected, is_class_value)          \
4027     do {                                                                         \
4028       size_t v = value;                                                          \
4029       size_t e = expected;                                                       \
4030       assert(SpaceManager::adjust_initial_chunk_size(v, (is_class_value)) == e,  \
4031              err_msg("Expected: " SIZE_FORMAT " got: " SIZE_FORMAT, e, v));      \
4032     } while (0)
4033 
4034     // Smallest (specialized)
4035     test_adjust_initial_chunk_size(1,            smallest, is_class);
4036     test_adjust_initial_chunk_size(smallest - 1, smallest, is_class);
4037     test_adjust_initial_chunk_size(smallest,     smallest, is_class);
4038 
4039     // Small
4040     test_adjust_initial_chunk_size(smallest + 1, normal, is_class);
4041     test_adjust_initial_chunk_size(normal - 1,   normal, is_class);
4042     test_adjust_initial_chunk_size(normal,       normal, is_class);
4043 
4044     // Medium
4045     test_adjust_initial_chunk_size(normal + 1, medium, is_class);
4046     test_adjust_initial_chunk_size(medium - 1, medium, is_class);
4047     test_adjust_initial_chunk_size(medium,     medium, is_class);
4048 
4049     // Humongous
4050     test_adjust_initial_chunk_size(medium + 1, medium + 1, is_class);
4051 
4052 #undef test_adjust_initial_chunk_size
4053   }
4054 
4055   static void test_adjust_initial_chunk_size() {
4056     test_adjust_initial_chunk_size(false);
4057     test_adjust_initial_chunk_size(true);
4058   }
4059 };
4060 
4061 void SpaceManager_test_adjust_initial_chunk_size() {
4062   SpaceManagerTest::test_adjust_initial_chunk_size();
4063 }
4064 
4065 // The following test is placed here instead of a gtest / unittest file
4066 // because the ChunkManager class is only available in this file.
4067 void ChunkManager_test_list_index() {
4068   ChunkManager manager(ClassSpecializedChunk, ClassSmallChunk, ClassMediumChunk);
4069 
4070   // Test previous bug where a query for a humongous class metachunk,
4071   // incorrectly matched the non-class medium metachunk size.
4072   {
4073     assert(MediumChunk > ClassMediumChunk, "Precondition for test");
4074 
4075     ChunkIndex index = manager.list_index(MediumChunk);
4076 
4077     assert(index == HumongousIndex,
4078            err_msg("Requested size is larger than ClassMediumChunk,"
4079            " so should return HumongousIndex. Got index: %d", (int)index));
4080   }
4081 
4082   // Check the specified sizes as well.
4083   {
4084     ChunkIndex index = manager.list_index(ClassSpecializedChunk);
4085     assert(index == SpecializedIndex, err_msg("Wrong index returned. Got index: %d", (int)index));
4086   }
4087   {
4088     ChunkIndex index = manager.list_index(ClassSmallChunk);
4089     assert(index == SmallIndex, err_msg("Wrong index returned. Got index: %d", (int)index));
4090   }
4091   {
4092     ChunkIndex index = manager.list_index(ClassMediumChunk);
4093     assert(index == MediumIndex, err_msg("Wrong index returned. Got index: %d", (int)index));
4094   }
4095   {
4096     ChunkIndex index = manager.list_index(ClassMediumChunk + 1);
4097     assert(index == HumongousIndex, err_msg("Wrong index returned. Got index: %d", (int)index));
4098   }
4099 }
4100 
4101 #endif