metaspace.cpp revision 13243:7235bc30c0d7
1/* 2 * Copyright (c) 2011, 2017, 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 "aot/aotLoader.hpp" 26#include "gc/shared/collectedHeap.hpp" 27#include "gc/shared/collectorPolicy.hpp" 28#include "gc/shared/gcLocker.hpp" 29#include "logging/log.hpp" 30#include "memory/allocation.hpp" 31#include "memory/binaryTreeDictionary.hpp" 32#include "memory/filemap.hpp" 33#include "memory/freeList.hpp" 34#include "memory/metachunk.hpp" 35#include "memory/metaspace.hpp" 36#include "memory/metaspaceGCThresholdUpdater.hpp" 37#include "memory/metaspaceShared.hpp" 38#include "memory/metaspaceTracer.hpp" 39#include "memory/resourceArea.hpp" 40#include "memory/universe.hpp" 41#include "runtime/atomic.hpp" 42#include "runtime/globals.hpp" 43#include "runtime/init.hpp" 44#include "runtime/java.hpp" 45#include "runtime/mutex.hpp" 46#include "runtime/orderAccess.inline.hpp" 47#include "services/memTracker.hpp" 48#include "services/memoryService.hpp" 49#include "utilities/copy.hpp" 50#include "utilities/debug.hpp" 51#include "utilities/macros.hpp" 52 53typedef BinaryTreeDictionary<Metablock, FreeList<Metablock> > BlockTreeDictionary; 54typedef BinaryTreeDictionary<Metachunk, FreeList<Metachunk> > ChunkTreeDictionary; 55 56// Set this constant to enable slow integrity checking of the free chunk lists 57const bool metaspace_slow_verify = false; 58 59size_t const allocation_from_dictionary_limit = 4 * K; 60 61MetaWord* last_allocated = 0; 62 63size_t Metaspace::_compressed_class_space_size; 64const MetaspaceTracer* Metaspace::_tracer = NULL; 65 66// Used in declarations in SpaceManager and ChunkManager 67enum 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// Helper, returns a descriptive name for the given index. 78static const char* chunk_size_name(ChunkIndex index) { 79 switch (index) { 80 case SpecializedIndex: 81 return "specialized"; 82 case SmallIndex: 83 return "small"; 84 case MediumIndex: 85 return "medium"; 86 case HumongousIndex: 87 return "humongous"; 88 default: 89 return "Invalid index"; 90 } 91} 92 93enum ChunkSizes { // in words. 94 ClassSpecializedChunk = 128, 95 SpecializedChunk = 128, 96 ClassSmallChunk = 256, 97 SmallChunk = 512, 98 ClassMediumChunk = 4 * K, 99 MediumChunk = 8 * K 100}; 101 102static ChunkIndex next_chunk_index(ChunkIndex i) { 103 assert(i < NumberOfInUseLists, "Out of bound"); 104 return (ChunkIndex) (i+1); 105} 106 107volatile intptr_t MetaspaceGC::_capacity_until_GC = 0; 108uint MetaspaceGC::_shrink_factor = 0; 109bool MetaspaceGC::_should_concurrent_collect = false; 110 111typedef class FreeList<Metachunk> ChunkList; 112 113// Manages the global free lists of chunks. 114class ChunkManager : public CHeapObj<mtInternal> { 115 friend class TestVirtualSpaceNodeTest; 116 117 // Free list of chunks of different sizes. 118 // SpecializedChunk 119 // SmallChunk 120 // MediumChunk 121 ChunkList _free_chunks[NumberOfFreeLists]; 122 123 // Return non-humongous chunk list by its index. 124 ChunkList* free_chunks(ChunkIndex index); 125 126 // Returns non-humongous chunk list for the given chunk word size. 127 ChunkList* find_free_chunks_list(size_t word_size); 128 129 // HumongousChunk 130 ChunkTreeDictionary _humongous_dictionary; 131 132 // Returns the humongous chunk dictionary. 133 ChunkTreeDictionary* humongous_dictionary() { 134 return &_humongous_dictionary; 135 } 136 137 // Size, in metaspace words, of all chunks managed by this ChunkManager 138 size_t _free_chunks_total; 139 // Number of chunks in this ChunkManager 140 size_t _free_chunks_count; 141 142 // Update counters after a chunk was added or removed removed. 143 void account_for_added_chunk(const Metachunk* c); 144 void account_for_removed_chunk(const Metachunk* c); 145 146 // Debug support 147 148 size_t sum_free_chunks(); 149 size_t sum_free_chunks_count(); 150 151 void locked_verify_free_chunks_total(); 152 void slow_locked_verify_free_chunks_total() { 153 if (metaspace_slow_verify) { 154 locked_verify_free_chunks_total(); 155 } 156 } 157 void locked_verify_free_chunks_count(); 158 void slow_locked_verify_free_chunks_count() { 159 if (metaspace_slow_verify) { 160 locked_verify_free_chunks_count(); 161 } 162 } 163 void verify_free_chunks_count(); 164 165 public: 166 167 ChunkManager(size_t specialized_size, size_t small_size, size_t medium_size) 168 : _free_chunks_total(0), _free_chunks_count(0) { 169 _free_chunks[SpecializedIndex].set_size(specialized_size); 170 _free_chunks[SmallIndex].set_size(small_size); 171 _free_chunks[MediumIndex].set_size(medium_size); 172 } 173 174 // add or delete (return) a chunk to the global freelist. 175 Metachunk* chunk_freelist_allocate(size_t word_size); 176 177 // Map a size to a list index assuming that there are lists 178 // for special, small, medium, and humongous chunks. 179 ChunkIndex list_index(size_t size); 180 181 // Map a given index to the chunk size. 182 size_t size_by_index(ChunkIndex index); 183 184 // Take a chunk from the ChunkManager. The chunk is expected to be in 185 // the chunk manager (the freelist if non-humongous, the dictionary if 186 // humongous). 187 void remove_chunk(Metachunk* chunk); 188 189 // Return a single chunk of type index to the ChunkManager. 190 void return_single_chunk(ChunkIndex index, Metachunk* chunk); 191 192 // Add the simple linked list of chunks to the freelist of chunks 193 // of type index. 194 void return_chunk_list(ChunkIndex index, Metachunk* chunk); 195 196 // Total of the space in the free chunks list 197 size_t free_chunks_total_words(); 198 size_t free_chunks_total_bytes(); 199 200 // Number of chunks in the free chunks list 201 size_t free_chunks_count(); 202 203 // Remove from a list by size. Selects list based on size of chunk. 204 Metachunk* free_chunks_get(size_t chunk_word_size); 205 206#define index_bounds_check(index) \ 207 assert(index == SpecializedIndex || \ 208 index == SmallIndex || \ 209 index == MediumIndex || \ 210 index == HumongousIndex, "Bad index: %d", (int) index) 211 212 size_t num_free_chunks(ChunkIndex index) const { 213 index_bounds_check(index); 214 215 if (index == HumongousIndex) { 216 return _humongous_dictionary.total_free_blocks(); 217 } 218 219 ssize_t count = _free_chunks[index].count(); 220 return count == -1 ? 0 : (size_t) count; 221 } 222 223 size_t size_free_chunks_in_bytes(ChunkIndex index) const { 224 index_bounds_check(index); 225 226 size_t word_size = 0; 227 if (index == HumongousIndex) { 228 word_size = _humongous_dictionary.total_size(); 229 } else { 230 const size_t size_per_chunk_in_words = _free_chunks[index].size(); 231 word_size = size_per_chunk_in_words * num_free_chunks(index); 232 } 233 234 return word_size * BytesPerWord; 235 } 236 237 MetaspaceChunkFreeListSummary chunk_free_list_summary() const { 238 return MetaspaceChunkFreeListSummary(num_free_chunks(SpecializedIndex), 239 num_free_chunks(SmallIndex), 240 num_free_chunks(MediumIndex), 241 num_free_chunks(HumongousIndex), 242 size_free_chunks_in_bytes(SpecializedIndex), 243 size_free_chunks_in_bytes(SmallIndex), 244 size_free_chunks_in_bytes(MediumIndex), 245 size_free_chunks_in_bytes(HumongousIndex)); 246 } 247 248 // Debug support 249 void verify(); 250 void slow_verify() { 251 if (metaspace_slow_verify) { 252 verify(); 253 } 254 } 255 void locked_verify(); 256 void slow_locked_verify() { 257 if (metaspace_slow_verify) { 258 locked_verify(); 259 } 260 } 261 void verify_free_chunks_total(); 262 263 void locked_print_free_chunks(outputStream* st); 264 void locked_print_sum_free_chunks(outputStream* st); 265 266 void print_on(outputStream* st) const; 267}; 268 269class SmallBlocks : public CHeapObj<mtClass> { 270 const static uint _small_block_max_size = sizeof(TreeChunk<Metablock, FreeList<Metablock> >)/HeapWordSize; 271 const static uint _small_block_min_size = sizeof(Metablock)/HeapWordSize; 272 273 private: 274 FreeList<Metablock> _small_lists[_small_block_max_size - _small_block_min_size]; 275 276 FreeList<Metablock>& list_at(size_t word_size) { 277 assert(word_size >= _small_block_min_size, "There are no metaspace objects less than %u words", _small_block_min_size); 278 return _small_lists[word_size - _small_block_min_size]; 279 } 280 281 public: 282 SmallBlocks() { 283 for (uint i = _small_block_min_size; i < _small_block_max_size; i++) { 284 uint k = i - _small_block_min_size; 285 _small_lists[k].set_size(i); 286 } 287 } 288 289 size_t total_size() const { 290 size_t result = 0; 291 for (uint i = _small_block_min_size; i < _small_block_max_size; i++) { 292 uint k = i - _small_block_min_size; 293 result = result + _small_lists[k].count() * _small_lists[k].size(); 294 } 295 return result; 296 } 297 298 static uint small_block_max_size() { return _small_block_max_size; } 299 static uint small_block_min_size() { return _small_block_min_size; } 300 301 MetaWord* get_block(size_t word_size) { 302 if (list_at(word_size).count() > 0) { 303 MetaWord* new_block = (MetaWord*) list_at(word_size).get_chunk_at_head(); 304 return new_block; 305 } else { 306 return NULL; 307 } 308 } 309 void return_block(Metablock* free_chunk, size_t word_size) { 310 list_at(word_size).return_chunk_at_head(free_chunk, false); 311 assert(list_at(word_size).count() > 0, "Should have a chunk"); 312 } 313 314 void print_on(outputStream* st) const { 315 st->print_cr("SmallBlocks:"); 316 for (uint i = _small_block_min_size; i < _small_block_max_size; i++) { 317 uint k = i - _small_block_min_size; 318 st->print_cr("small_lists size " SIZE_FORMAT " count " SIZE_FORMAT, _small_lists[k].size(), _small_lists[k].count()); 319 } 320 } 321}; 322 323// Used to manage the free list of Metablocks (a block corresponds 324// to the allocation of a quantum of metadata). 325class BlockFreelist : public CHeapObj<mtClass> { 326 BlockTreeDictionary* const _dictionary; 327 SmallBlocks* _small_blocks; 328 329 // Only allocate and split from freelist if the size of the allocation 330 // is at least 1/4th the size of the available block. 331 const static int WasteMultiplier = 4; 332 333 // Accessors 334 BlockTreeDictionary* dictionary() const { return _dictionary; } 335 SmallBlocks* small_blocks() { 336 if (_small_blocks == NULL) { 337 _small_blocks = new SmallBlocks(); 338 } 339 return _small_blocks; 340 } 341 342 public: 343 BlockFreelist(); 344 ~BlockFreelist(); 345 346 // Get and return a block to the free list 347 MetaWord* get_block(size_t word_size); 348 void return_block(MetaWord* p, size_t word_size); 349 350 size_t total_size() const { 351 size_t result = dictionary()->total_size(); 352 if (_small_blocks != NULL) { 353 result = result + _small_blocks->total_size(); 354 } 355 return result; 356 } 357 358 static size_t min_dictionary_size() { return TreeChunk<Metablock, FreeList<Metablock> >::min_size(); } 359 void print_on(outputStream* st) const; 360}; 361 362// A VirtualSpaceList node. 363class VirtualSpaceNode : public CHeapObj<mtClass> { 364 friend class VirtualSpaceList; 365 366 // Link to next VirtualSpaceNode 367 VirtualSpaceNode* _next; 368 369 // total in the VirtualSpace 370 MemRegion _reserved; 371 ReservedSpace _rs; 372 VirtualSpace _virtual_space; 373 MetaWord* _top; 374 // count of chunks contained in this VirtualSpace 375 uintx _container_count; 376 377 // Convenience functions to access the _virtual_space 378 char* low() const { return virtual_space()->low(); } 379 char* high() const { return virtual_space()->high(); } 380 381 // The first Metachunk will be allocated at the bottom of the 382 // VirtualSpace 383 Metachunk* first_chunk() { return (Metachunk*) bottom(); } 384 385 // Committed but unused space in the virtual space 386 size_t free_words_in_vs() const; 387 public: 388 389 VirtualSpaceNode(size_t byte_size); 390 VirtualSpaceNode(ReservedSpace rs) : _top(NULL), _next(NULL), _rs(rs), _container_count(0) {} 391 ~VirtualSpaceNode(); 392 393 // Convenience functions for logical bottom and end 394 MetaWord* bottom() const { return (MetaWord*) _virtual_space.low(); } 395 MetaWord* end() const { return (MetaWord*) _virtual_space.high(); } 396 397 bool contains(const void* ptr) { return ptr >= low() && ptr < high(); } 398 399 size_t reserved_words() const { return _virtual_space.reserved_size() / BytesPerWord; } 400 size_t committed_words() const { return _virtual_space.actual_committed_size() / BytesPerWord; } 401 402 bool is_pre_committed() const { return _virtual_space.special(); } 403 404 // address of next available space in _virtual_space; 405 // Accessors 406 VirtualSpaceNode* next() { return _next; } 407 void set_next(VirtualSpaceNode* v) { _next = v; } 408 409 void set_reserved(MemRegion const v) { _reserved = v; } 410 void set_top(MetaWord* v) { _top = v; } 411 412 // Accessors 413 MemRegion* reserved() { return &_reserved; } 414 VirtualSpace* virtual_space() const { return (VirtualSpace*) &_virtual_space; } 415 416 // Returns true if "word_size" is available in the VirtualSpace 417 bool is_available(size_t word_size) { return word_size <= pointer_delta(end(), _top, sizeof(MetaWord)); } 418 419 MetaWord* top() const { return _top; } 420 void inc_top(size_t word_size) { _top += word_size; } 421 422 uintx container_count() { return _container_count; } 423 void inc_container_count(); 424 void dec_container_count(); 425#ifdef ASSERT 426 uintx container_count_slow(); 427 void verify_container_count(); 428#endif 429 430 // used and capacity in this single entry in the list 431 size_t used_words_in_vs() const; 432 size_t capacity_words_in_vs() const; 433 434 bool initialize(); 435 436 // get space from the virtual space 437 Metachunk* take_from_committed(size_t chunk_word_size); 438 439 // Allocate a chunk from the virtual space and return it. 440 Metachunk* get_chunk_vs(size_t chunk_word_size); 441 442 // Expands/shrinks the committed space in a virtual space. Delegates 443 // to Virtualspace 444 bool expand_by(size_t min_words, size_t preferred_words); 445 446 // In preparation for deleting this node, remove all the chunks 447 // in the node from any freelist. 448 void purge(ChunkManager* chunk_manager); 449 450 // If an allocation doesn't fit in the current node a new node is created. 451 // Allocate chunks out of the remaining committed space in this node 452 // to avoid wasting that memory. 453 // This always adds up because all the chunk sizes are multiples of 454 // the smallest chunk size. 455 void retire(ChunkManager* chunk_manager); 456 457#ifdef ASSERT 458 // Debug support 459 void mangle(); 460#endif 461 462 void print_on(outputStream* st) const; 463}; 464 465#define assert_is_aligned(value, alignment) \ 466 assert(is_aligned((value), (alignment)), \ 467 SIZE_FORMAT_HEX " is not aligned to " \ 468 SIZE_FORMAT, (size_t)(uintptr_t)value, (alignment)) 469 470// Decide if large pages should be committed when the memory is reserved. 471static bool should_commit_large_pages_when_reserving(size_t bytes) { 472 if (UseLargePages && UseLargePagesInMetaspace && !os::can_commit_large_page_memory()) { 473 size_t words = bytes / BytesPerWord; 474 bool is_class = false; // We never reserve large pages for the class space. 475 if (MetaspaceGC::can_expand(words, is_class) && 476 MetaspaceGC::allowed_expansion() >= words) { 477 return true; 478 } 479 } 480 481 return false; 482} 483 484 // byte_size is the size of the associated virtualspace. 485VirtualSpaceNode::VirtualSpaceNode(size_t bytes) : _top(NULL), _next(NULL), _rs(), _container_count(0) { 486 assert_is_aligned(bytes, Metaspace::reserve_alignment()); 487 488#if INCLUDE_CDS 489 // This allocates memory with mmap. For DumpSharedspaces, try to reserve 490 // configurable address, generally at the top of the Java heap so other 491 // memory addresses don't conflict. 492 if (DumpSharedSpaces) { 493 bool large_pages = false; // No large pages when dumping the CDS archive. 494 char* shared_base = align_up((char*)SharedBaseAddress, Metaspace::reserve_alignment()); 495 496 _rs = ReservedSpace(bytes, Metaspace::reserve_alignment(), large_pages, shared_base); 497 if (_rs.is_reserved()) { 498 assert(shared_base == 0 || _rs.base() == shared_base, "should match"); 499 } else { 500 // Get a mmap region anywhere if the SharedBaseAddress fails. 501 _rs = ReservedSpace(bytes, Metaspace::reserve_alignment(), large_pages); 502 } 503 if (!_rs.is_reserved()) { 504 vm_exit_during_initialization("Unable to allocate memory for shared space", 505 err_msg(SIZE_FORMAT " bytes.", bytes)); 506 } 507 MetaspaceShared::initialize_shared_rs(&_rs); 508 } else 509#endif 510 { 511 bool large_pages = should_commit_large_pages_when_reserving(bytes); 512 513 _rs = ReservedSpace(bytes, Metaspace::reserve_alignment(), large_pages); 514 } 515 516 if (_rs.is_reserved()) { 517 assert(_rs.base() != NULL, "Catch if we get a NULL address"); 518 assert(_rs.size() != 0, "Catch if we get a 0 size"); 519 assert_is_aligned(_rs.base(), Metaspace::reserve_alignment()); 520 assert_is_aligned(_rs.size(), Metaspace::reserve_alignment()); 521 522 MemTracker::record_virtual_memory_type((address)_rs.base(), mtClass); 523 } 524} 525 526void VirtualSpaceNode::purge(ChunkManager* chunk_manager) { 527 Metachunk* chunk = first_chunk(); 528 Metachunk* invalid_chunk = (Metachunk*) top(); 529 while (chunk < invalid_chunk ) { 530 assert(chunk->is_tagged_free(), "Should be tagged free"); 531 MetaWord* next = ((MetaWord*)chunk) + chunk->word_size(); 532 chunk_manager->remove_chunk(chunk); 533 assert(chunk->next() == NULL && 534 chunk->prev() == NULL, 535 "Was not removed from its list"); 536 chunk = (Metachunk*) next; 537 } 538} 539 540#ifdef ASSERT 541uintx VirtualSpaceNode::container_count_slow() { 542 uintx count = 0; 543 Metachunk* chunk = first_chunk(); 544 Metachunk* invalid_chunk = (Metachunk*) top(); 545 while (chunk < invalid_chunk ) { 546 MetaWord* next = ((MetaWord*)chunk) + chunk->word_size(); 547 // Don't count the chunks on the free lists. Those are 548 // still part of the VirtualSpaceNode but not currently 549 // counted. 550 if (!chunk->is_tagged_free()) { 551 count++; 552 } 553 chunk = (Metachunk*) next; 554 } 555 return count; 556} 557#endif 558 559// List of VirtualSpaces for metadata allocation. 560class VirtualSpaceList : public CHeapObj<mtClass> { 561 friend class VirtualSpaceNode; 562 563 enum VirtualSpaceSizes { 564 VirtualSpaceSize = 256 * K 565 }; 566 567 // Head of the list 568 VirtualSpaceNode* _virtual_space_list; 569 // virtual space currently being used for allocations 570 VirtualSpaceNode* _current_virtual_space; 571 572 // Is this VirtualSpaceList used for the compressed class space 573 bool _is_class; 574 575 // Sum of reserved and committed memory in the virtual spaces 576 size_t _reserved_words; 577 size_t _committed_words; 578 579 // Number of virtual spaces 580 size_t _virtual_space_count; 581 582 ~VirtualSpaceList(); 583 584 VirtualSpaceNode* virtual_space_list() const { return _virtual_space_list; } 585 586 void set_virtual_space_list(VirtualSpaceNode* v) { 587 _virtual_space_list = v; 588 } 589 void set_current_virtual_space(VirtualSpaceNode* v) { 590 _current_virtual_space = v; 591 } 592 593 void link_vs(VirtualSpaceNode* new_entry); 594 595 // Get another virtual space and add it to the list. This 596 // is typically prompted by a failed attempt to allocate a chunk 597 // and is typically followed by the allocation of a chunk. 598 bool create_new_virtual_space(size_t vs_word_size); 599 600 // Chunk up the unused committed space in the current 601 // virtual space and add the chunks to the free list. 602 void retire_current_virtual_space(); 603 604 public: 605 VirtualSpaceList(size_t word_size); 606 VirtualSpaceList(ReservedSpace rs); 607 608 size_t free_bytes(); 609 610 Metachunk* get_new_chunk(size_t chunk_word_size, 611 size_t suggested_commit_granularity); 612 613 bool expand_node_by(VirtualSpaceNode* node, 614 size_t min_words, 615 size_t preferred_words); 616 617 bool expand_by(size_t min_words, 618 size_t preferred_words); 619 620 VirtualSpaceNode* current_virtual_space() { 621 return _current_virtual_space; 622 } 623 624 bool is_class() const { return _is_class; } 625 626 bool initialization_succeeded() { return _virtual_space_list != NULL; } 627 628 size_t reserved_words() { return _reserved_words; } 629 size_t reserved_bytes() { return reserved_words() * BytesPerWord; } 630 size_t committed_words() { return _committed_words; } 631 size_t committed_bytes() { return committed_words() * BytesPerWord; } 632 633 void inc_reserved_words(size_t v); 634 void dec_reserved_words(size_t v); 635 void inc_committed_words(size_t v); 636 void dec_committed_words(size_t v); 637 void inc_virtual_space_count(); 638 void dec_virtual_space_count(); 639 640 bool contains(const void* ptr); 641 642 // Unlink empty VirtualSpaceNodes and free it. 643 void purge(ChunkManager* chunk_manager); 644 645 void print_on(outputStream* st) const; 646 647 class VirtualSpaceListIterator : public StackObj { 648 VirtualSpaceNode* _virtual_spaces; 649 public: 650 VirtualSpaceListIterator(VirtualSpaceNode* virtual_spaces) : 651 _virtual_spaces(virtual_spaces) {} 652 653 bool repeat() { 654 return _virtual_spaces != NULL; 655 } 656 657 VirtualSpaceNode* get_next() { 658 VirtualSpaceNode* result = _virtual_spaces; 659 if (_virtual_spaces != NULL) { 660 _virtual_spaces = _virtual_spaces->next(); 661 } 662 return result; 663 } 664 }; 665}; 666 667class Metadebug : AllStatic { 668 // Debugging support for Metaspaces 669 static int _allocation_fail_alot_count; 670 671 public: 672 673 static void init_allocation_fail_alot_count(); 674#ifdef ASSERT 675 static bool test_metadata_failure(); 676#endif 677}; 678 679int Metadebug::_allocation_fail_alot_count = 0; 680 681// SpaceManager - used by Metaspace to handle allocations 682class SpaceManager : public CHeapObj<mtClass> { 683 friend class Metaspace; 684 friend class Metadebug; 685 686 private: 687 688 // protects allocations 689 Mutex* const _lock; 690 691 // Type of metadata allocated. 692 Metaspace::MetadataType _mdtype; 693 694 // List of chunks in use by this SpaceManager. Allocations 695 // are done from the current chunk. The list is used for deallocating 696 // chunks when the SpaceManager is freed. 697 Metachunk* _chunks_in_use[NumberOfInUseLists]; 698 Metachunk* _current_chunk; 699 700 // Maximum number of small chunks to allocate to a SpaceManager 701 static uint const _small_chunk_limit; 702 703 // Sum of all space in allocated chunks 704 size_t _allocated_blocks_words; 705 706 // Sum of all allocated chunks 707 size_t _allocated_chunks_words; 708 size_t _allocated_chunks_count; 709 710 // Free lists of blocks are per SpaceManager since they 711 // are assumed to be in chunks in use by the SpaceManager 712 // and all chunks in use by a SpaceManager are freed when 713 // the class loader using the SpaceManager is collected. 714 BlockFreelist* _block_freelists; 715 716 // protects virtualspace and chunk expansions 717 static const char* _expand_lock_name; 718 static const int _expand_lock_rank; 719 static Mutex* const _expand_lock; 720 721 private: 722 // Accessors 723 Metachunk* chunks_in_use(ChunkIndex index) const { return _chunks_in_use[index]; } 724 void set_chunks_in_use(ChunkIndex index, Metachunk* v) { 725 _chunks_in_use[index] = v; 726 } 727 728 BlockFreelist* block_freelists() const { return _block_freelists; } 729 730 Metaspace::MetadataType mdtype() { return _mdtype; } 731 732 VirtualSpaceList* vs_list() const { return Metaspace::get_space_list(_mdtype); } 733 ChunkManager* chunk_manager() const { return Metaspace::get_chunk_manager(_mdtype); } 734 735 Metachunk* current_chunk() const { return _current_chunk; } 736 void set_current_chunk(Metachunk* v) { 737 _current_chunk = v; 738 } 739 740 Metachunk* find_current_chunk(size_t word_size); 741 742 // Add chunk to the list of chunks in use 743 void add_chunk(Metachunk* v, bool make_current); 744 void retire_current_chunk(); 745 746 Mutex* lock() const { return _lock; } 747 748 protected: 749 void initialize(); 750 751 public: 752 SpaceManager(Metaspace::MetadataType mdtype, 753 Mutex* lock); 754 ~SpaceManager(); 755 756 enum ChunkMultiples { 757 MediumChunkMultiple = 4 758 }; 759 760 static size_t specialized_chunk_size(bool is_class) { return is_class ? ClassSpecializedChunk : SpecializedChunk; } 761 static size_t small_chunk_size(bool is_class) { return is_class ? ClassSmallChunk : SmallChunk; } 762 static size_t medium_chunk_size(bool is_class) { return is_class ? ClassMediumChunk : MediumChunk; } 763 764 static size_t smallest_chunk_size(bool is_class) { return specialized_chunk_size(is_class); } 765 766 // Accessors 767 bool is_class() const { return _mdtype == Metaspace::ClassType; } 768 769 size_t specialized_chunk_size() const { return specialized_chunk_size(is_class()); } 770 size_t small_chunk_size() const { return small_chunk_size(is_class()); } 771 size_t medium_chunk_size() const { return medium_chunk_size(is_class()); } 772 773 size_t smallest_chunk_size() const { return smallest_chunk_size(is_class()); } 774 775 size_t medium_chunk_bunch() const { return medium_chunk_size() * MediumChunkMultiple; } 776 777 size_t allocated_blocks_words() const { return _allocated_blocks_words; } 778 size_t allocated_blocks_bytes() const { return _allocated_blocks_words * BytesPerWord; } 779 size_t allocated_chunks_words() const { return _allocated_chunks_words; } 780 size_t allocated_chunks_bytes() const { return _allocated_chunks_words * BytesPerWord; } 781 size_t allocated_chunks_count() const { return _allocated_chunks_count; } 782 783 bool is_humongous(size_t word_size) { return word_size > medium_chunk_size(); } 784 785 static Mutex* expand_lock() { return _expand_lock; } 786 787 // Increment the per Metaspace and global running sums for Metachunks 788 // by the given size. This is used when a Metachunk to added to 789 // the in-use list. 790 void inc_size_metrics(size_t words); 791 // Increment the per Metaspace and global running sums Metablocks by the given 792 // size. This is used when a Metablock is allocated. 793 void inc_used_metrics(size_t words); 794 // Delete the portion of the running sums for this SpaceManager. That is, 795 // the globals running sums for the Metachunks and Metablocks are 796 // decremented for all the Metachunks in-use by this SpaceManager. 797 void dec_total_from_size_metrics(); 798 799 // Adjust the initial chunk size to match one of the fixed chunk list sizes, 800 // or return the unadjusted size if the requested size is humongous. 801 static size_t adjust_initial_chunk_size(size_t requested, bool is_class_space); 802 size_t adjust_initial_chunk_size(size_t requested) const; 803 804 // Get the initial chunks size for this metaspace type. 805 size_t get_initial_chunk_size(Metaspace::MetaspaceType type) const; 806 807 size_t sum_capacity_in_chunks_in_use() const; 808 size_t sum_used_in_chunks_in_use() const; 809 size_t sum_free_in_chunks_in_use() const; 810 size_t sum_waste_in_chunks_in_use() const; 811 size_t sum_waste_in_chunks_in_use(ChunkIndex index ) const; 812 813 size_t sum_count_in_chunks_in_use(); 814 size_t sum_count_in_chunks_in_use(ChunkIndex i); 815 816 Metachunk* get_new_chunk(size_t chunk_word_size); 817 818 // Block allocation and deallocation. 819 // Allocates a block from the current chunk 820 MetaWord* allocate(size_t word_size); 821 // Allocates a block from a small chunk 822 MetaWord* get_small_chunk_and_allocate(size_t word_size); 823 824 // Helper for allocations 825 MetaWord* allocate_work(size_t word_size); 826 827 // Returns a block to the per manager freelist 828 void deallocate(MetaWord* p, size_t word_size); 829 830 // Based on the allocation size and a minimum chunk size, 831 // returned chunk size (for expanding space for chunk allocation). 832 size_t calc_chunk_size(size_t allocation_word_size); 833 834 // Called when an allocation from the current chunk fails. 835 // Gets a new chunk (may require getting a new virtual space), 836 // and allocates from that chunk. 837 MetaWord* grow_and_allocate(size_t word_size); 838 839 // Notify memory usage to MemoryService. 840 void track_metaspace_memory_usage(); 841 842 // debugging support. 843 844 void dump(outputStream* const out) const; 845 void print_on(outputStream* st) const; 846 void locked_print_chunks_in_use_on(outputStream* st) const; 847 848 void verify(); 849 void verify_chunk_size(Metachunk* chunk); 850#ifdef ASSERT 851 void verify_allocated_blocks_words(); 852#endif 853 854 // This adjusts the size given to be greater than the minimum allocation size in 855 // words for data in metaspace. Esentially the minimum size is currently 3 words. 856 size_t get_allocation_word_size(size_t word_size) { 857 size_t byte_size = word_size * BytesPerWord; 858 859 size_t raw_bytes_size = MAX2(byte_size, sizeof(Metablock)); 860 raw_bytes_size = align_up(raw_bytes_size, Metachunk::object_alignment()); 861 862 size_t raw_word_size = raw_bytes_size / BytesPerWord; 863 assert(raw_word_size * BytesPerWord == raw_bytes_size, "Size problem"); 864 865 return raw_word_size; 866 } 867}; 868 869uint const SpaceManager::_small_chunk_limit = 4; 870 871const char* SpaceManager::_expand_lock_name = 872 "SpaceManager chunk allocation lock"; 873const int SpaceManager::_expand_lock_rank = Monitor::leaf - 1; 874Mutex* const SpaceManager::_expand_lock = 875 new Mutex(SpaceManager::_expand_lock_rank, 876 SpaceManager::_expand_lock_name, 877 Mutex::_allow_vm_block_flag, 878 Monitor::_safepoint_check_never); 879 880void VirtualSpaceNode::inc_container_count() { 881 assert_lock_strong(SpaceManager::expand_lock()); 882 _container_count++; 883} 884 885void VirtualSpaceNode::dec_container_count() { 886 assert_lock_strong(SpaceManager::expand_lock()); 887 _container_count--; 888} 889 890#ifdef ASSERT 891void VirtualSpaceNode::verify_container_count() { 892 assert(_container_count == container_count_slow(), 893 "Inconsistency in container_count _container_count " UINTX_FORMAT 894 " container_count_slow() " UINTX_FORMAT, _container_count, container_count_slow()); 895} 896#endif 897 898// BlockFreelist methods 899 900BlockFreelist::BlockFreelist() : _dictionary(new BlockTreeDictionary()), _small_blocks(NULL) {} 901 902BlockFreelist::~BlockFreelist() { 903 delete _dictionary; 904 if (_small_blocks != NULL) { 905 delete _small_blocks; 906 } 907} 908 909void BlockFreelist::return_block(MetaWord* p, size_t word_size) { 910 assert(word_size >= SmallBlocks::small_block_min_size(), "never return dark matter"); 911 912 Metablock* free_chunk = ::new (p) Metablock(word_size); 913 if (word_size < SmallBlocks::small_block_max_size()) { 914 small_blocks()->return_block(free_chunk, word_size); 915 } else { 916 dictionary()->return_chunk(free_chunk); 917} 918 log_trace(gc, metaspace, freelist, blocks)("returning block at " INTPTR_FORMAT " size = " 919 SIZE_FORMAT, p2i(free_chunk), word_size); 920} 921 922MetaWord* BlockFreelist::get_block(size_t word_size) { 923 assert(word_size >= SmallBlocks::small_block_min_size(), "never get dark matter"); 924 925 // Try small_blocks first. 926 if (word_size < SmallBlocks::small_block_max_size()) { 927 // Don't create small_blocks() until needed. small_blocks() allocates the small block list for 928 // this space manager. 929 MetaWord* new_block = (MetaWord*) small_blocks()->get_block(word_size); 930 if (new_block != NULL) { 931 log_trace(gc, metaspace, freelist, blocks)("getting block at " INTPTR_FORMAT " size = " SIZE_FORMAT, 932 p2i(new_block), word_size); 933 return new_block; 934 } 935 } 936 937 if (word_size < BlockFreelist::min_dictionary_size()) { 938 // If allocation in small blocks fails, this is Dark Matter. Too small for dictionary. 939 return NULL; 940 } 941 942 Metablock* free_block = 943 dictionary()->get_chunk(word_size, FreeBlockDictionary<Metablock>::atLeast); 944 if (free_block == NULL) { 945 return NULL; 946 } 947 948 const size_t block_size = free_block->size(); 949 if (block_size > WasteMultiplier * word_size) { 950 return_block((MetaWord*)free_block, block_size); 951 return NULL; 952 } 953 954 MetaWord* new_block = (MetaWord*)free_block; 955 assert(block_size >= word_size, "Incorrect size of block from freelist"); 956 const size_t unused = block_size - word_size; 957 if (unused >= SmallBlocks::small_block_min_size()) { 958 return_block(new_block + word_size, unused); 959 } 960 961 log_trace(gc, metaspace, freelist, blocks)("getting block at " INTPTR_FORMAT " size = " SIZE_FORMAT, 962 p2i(new_block), word_size); 963 return new_block; 964} 965 966void BlockFreelist::print_on(outputStream* st) const { 967 dictionary()->print_free_lists(st); 968 if (_small_blocks != NULL) { 969 _small_blocks->print_on(st); 970 } 971} 972 973// VirtualSpaceNode methods 974 975VirtualSpaceNode::~VirtualSpaceNode() { 976 _rs.release(); 977#ifdef ASSERT 978 size_t word_size = sizeof(*this) / BytesPerWord; 979 Copy::fill_to_words((HeapWord*) this, word_size, 0xf1f1f1f1); 980#endif 981} 982 983size_t VirtualSpaceNode::used_words_in_vs() const { 984 return pointer_delta(top(), bottom(), sizeof(MetaWord)); 985} 986 987// Space committed in the VirtualSpace 988size_t VirtualSpaceNode::capacity_words_in_vs() const { 989 return pointer_delta(end(), bottom(), sizeof(MetaWord)); 990} 991 992size_t VirtualSpaceNode::free_words_in_vs() const { 993 return pointer_delta(end(), top(), sizeof(MetaWord)); 994} 995 996// Allocates the chunk from the virtual space only. 997// This interface is also used internally for debugging. Not all 998// chunks removed here are necessarily used for allocation. 999Metachunk* VirtualSpaceNode::take_from_committed(size_t chunk_word_size) { 1000 // Bottom of the new chunk 1001 MetaWord* chunk_limit = top(); 1002 assert(chunk_limit != NULL, "Not safe to call this method"); 1003 1004 // The virtual spaces are always expanded by the 1005 // commit granularity to enforce the following condition. 1006 // Without this the is_available check will not work correctly. 1007 assert(_virtual_space.committed_size() == _virtual_space.actual_committed_size(), 1008 "The committed memory doesn't match the expanded memory."); 1009 1010 if (!is_available(chunk_word_size)) { 1011 Log(gc, metaspace, freelist) log; 1012 log.debug("VirtualSpaceNode::take_from_committed() not available " SIZE_FORMAT " words ", chunk_word_size); 1013 // Dump some information about the virtual space that is nearly full 1014 ResourceMark rm; 1015 print_on(log.debug_stream()); 1016 return NULL; 1017 } 1018 1019 // Take the space (bump top on the current virtual space). 1020 inc_top(chunk_word_size); 1021 1022 // Initialize the chunk 1023 Metachunk* result = ::new (chunk_limit) Metachunk(chunk_word_size, this); 1024 return result; 1025} 1026 1027 1028// Expand the virtual space (commit more of the reserved space) 1029bool VirtualSpaceNode::expand_by(size_t min_words, size_t preferred_words) { 1030 size_t min_bytes = min_words * BytesPerWord; 1031 size_t preferred_bytes = preferred_words * BytesPerWord; 1032 1033 size_t uncommitted = virtual_space()->reserved_size() - virtual_space()->actual_committed_size(); 1034 1035 if (uncommitted < min_bytes) { 1036 return false; 1037 } 1038 1039 size_t commit = MIN2(preferred_bytes, uncommitted); 1040 bool result = virtual_space()->expand_by(commit, false); 1041 1042 assert(result, "Failed to commit memory"); 1043 1044 return result; 1045} 1046 1047Metachunk* VirtualSpaceNode::get_chunk_vs(size_t chunk_word_size) { 1048 assert_lock_strong(SpaceManager::expand_lock()); 1049 Metachunk* result = take_from_committed(chunk_word_size); 1050 if (result != NULL) { 1051 inc_container_count(); 1052 } 1053 return result; 1054} 1055 1056bool VirtualSpaceNode::initialize() { 1057 1058 if (!_rs.is_reserved()) { 1059 return false; 1060 } 1061 1062 // These are necessary restriction to make sure that the virtual space always 1063 // grows in steps of Metaspace::commit_alignment(). If both base and size are 1064 // aligned only the middle alignment of the VirtualSpace is used. 1065 assert_is_aligned(_rs.base(), Metaspace::commit_alignment()); 1066 assert_is_aligned(_rs.size(), Metaspace::commit_alignment()); 1067 1068 // ReservedSpaces marked as special will have the entire memory 1069 // pre-committed. Setting a committed size will make sure that 1070 // committed_size and actual_committed_size agrees. 1071 size_t pre_committed_size = _rs.special() ? _rs.size() : 0; 1072 1073 bool result = virtual_space()->initialize_with_granularity(_rs, pre_committed_size, 1074 Metaspace::commit_alignment()); 1075 if (result) { 1076 assert(virtual_space()->committed_size() == virtual_space()->actual_committed_size(), 1077 "Checking that the pre-committed memory was registered by the VirtualSpace"); 1078 1079 set_top((MetaWord*)virtual_space()->low()); 1080 set_reserved(MemRegion((HeapWord*)_rs.base(), 1081 (HeapWord*)(_rs.base() + _rs.size()))); 1082 1083 assert(reserved()->start() == (HeapWord*) _rs.base(), 1084 "Reserved start was not set properly " PTR_FORMAT 1085 " != " PTR_FORMAT, p2i(reserved()->start()), p2i(_rs.base())); 1086 assert(reserved()->word_size() == _rs.size() / BytesPerWord, 1087 "Reserved size was not set properly " SIZE_FORMAT 1088 " != " SIZE_FORMAT, reserved()->word_size(), 1089 _rs.size() / BytesPerWord); 1090 } 1091 1092 return result; 1093} 1094 1095void VirtualSpaceNode::print_on(outputStream* st) const { 1096 size_t used = used_words_in_vs(); 1097 size_t capacity = capacity_words_in_vs(); 1098 VirtualSpace* vs = virtual_space(); 1099 st->print_cr(" space @ " PTR_FORMAT " " SIZE_FORMAT "K, " SIZE_FORMAT_W(3) "%% used " 1100 "[" PTR_FORMAT ", " PTR_FORMAT ", " 1101 PTR_FORMAT ", " PTR_FORMAT ")", 1102 p2i(vs), capacity / K, 1103 capacity == 0 ? 0 : used * 100 / capacity, 1104 p2i(bottom()), p2i(top()), p2i(end()), 1105 p2i(vs->high_boundary())); 1106} 1107 1108#ifdef ASSERT 1109void VirtualSpaceNode::mangle() { 1110 size_t word_size = capacity_words_in_vs(); 1111 Copy::fill_to_words((HeapWord*) low(), word_size, 0xf1f1f1f1); 1112} 1113#endif // ASSERT 1114 1115// VirtualSpaceList methods 1116// Space allocated from the VirtualSpace 1117 1118VirtualSpaceList::~VirtualSpaceList() { 1119 VirtualSpaceListIterator iter(virtual_space_list()); 1120 while (iter.repeat()) { 1121 VirtualSpaceNode* vsl = iter.get_next(); 1122 delete vsl; 1123 } 1124} 1125 1126void VirtualSpaceList::inc_reserved_words(size_t v) { 1127 assert_lock_strong(SpaceManager::expand_lock()); 1128 _reserved_words = _reserved_words + v; 1129} 1130void VirtualSpaceList::dec_reserved_words(size_t v) { 1131 assert_lock_strong(SpaceManager::expand_lock()); 1132 _reserved_words = _reserved_words - v; 1133} 1134 1135#define assert_committed_below_limit() \ 1136 assert(MetaspaceAux::committed_bytes() <= MaxMetaspaceSize, \ 1137 "Too much committed memory. Committed: " SIZE_FORMAT \ 1138 " limit (MaxMetaspaceSize): " SIZE_FORMAT, \ 1139 MetaspaceAux::committed_bytes(), MaxMetaspaceSize); 1140 1141void VirtualSpaceList::inc_committed_words(size_t v) { 1142 assert_lock_strong(SpaceManager::expand_lock()); 1143 _committed_words = _committed_words + v; 1144 1145 assert_committed_below_limit(); 1146} 1147void VirtualSpaceList::dec_committed_words(size_t v) { 1148 assert_lock_strong(SpaceManager::expand_lock()); 1149 _committed_words = _committed_words - v; 1150 1151 assert_committed_below_limit(); 1152} 1153 1154void VirtualSpaceList::inc_virtual_space_count() { 1155 assert_lock_strong(SpaceManager::expand_lock()); 1156 _virtual_space_count++; 1157} 1158void VirtualSpaceList::dec_virtual_space_count() { 1159 assert_lock_strong(SpaceManager::expand_lock()); 1160 _virtual_space_count--; 1161} 1162 1163void ChunkManager::remove_chunk(Metachunk* chunk) { 1164 size_t word_size = chunk->word_size(); 1165 ChunkIndex index = list_index(word_size); 1166 if (index != HumongousIndex) { 1167 free_chunks(index)->remove_chunk(chunk); 1168 } else { 1169 humongous_dictionary()->remove_chunk(chunk); 1170 } 1171 1172 // Chunk has been removed from the chunks free list, update counters. 1173 account_for_removed_chunk(chunk); 1174} 1175 1176// Walk the list of VirtualSpaceNodes and delete 1177// nodes with a 0 container_count. Remove Metachunks in 1178// the node from their respective freelists. 1179void VirtualSpaceList::purge(ChunkManager* chunk_manager) { 1180 assert(SafepointSynchronize::is_at_safepoint(), "must be called at safepoint for contains to work"); 1181 assert_lock_strong(SpaceManager::expand_lock()); 1182 // Don't use a VirtualSpaceListIterator because this 1183 // list is being changed and a straightforward use of an iterator is not safe. 1184 VirtualSpaceNode* purged_vsl = NULL; 1185 VirtualSpaceNode* prev_vsl = virtual_space_list(); 1186 VirtualSpaceNode* next_vsl = prev_vsl; 1187 while (next_vsl != NULL) { 1188 VirtualSpaceNode* vsl = next_vsl; 1189 DEBUG_ONLY(vsl->verify_container_count();) 1190 next_vsl = vsl->next(); 1191 // Don't free the current virtual space since it will likely 1192 // be needed soon. 1193 if (vsl->container_count() == 0 && vsl != current_virtual_space()) { 1194 // Unlink it from the list 1195 if (prev_vsl == vsl) { 1196 // This is the case of the current node being the first node. 1197 assert(vsl == virtual_space_list(), "Expected to be the first node"); 1198 set_virtual_space_list(vsl->next()); 1199 } else { 1200 prev_vsl->set_next(vsl->next()); 1201 } 1202 1203 vsl->purge(chunk_manager); 1204 dec_reserved_words(vsl->reserved_words()); 1205 dec_committed_words(vsl->committed_words()); 1206 dec_virtual_space_count(); 1207 purged_vsl = vsl; 1208 delete vsl; 1209 } else { 1210 prev_vsl = vsl; 1211 } 1212 } 1213#ifdef ASSERT 1214 if (purged_vsl != NULL) { 1215 // List should be stable enough to use an iterator here. 1216 VirtualSpaceListIterator iter(virtual_space_list()); 1217 while (iter.repeat()) { 1218 VirtualSpaceNode* vsl = iter.get_next(); 1219 assert(vsl != purged_vsl, "Purge of vsl failed"); 1220 } 1221 } 1222#endif 1223} 1224 1225 1226// This function looks at the mmap regions in the metaspace without locking. 1227// The chunks are added with store ordering and not deleted except for at 1228// unloading time during a safepoint. 1229bool VirtualSpaceList::contains(const void* ptr) { 1230 // List should be stable enough to use an iterator here because removing virtual 1231 // space nodes is only allowed at a safepoint. 1232 VirtualSpaceListIterator iter(virtual_space_list()); 1233 while (iter.repeat()) { 1234 VirtualSpaceNode* vsn = iter.get_next(); 1235 if (vsn->contains(ptr)) { 1236 return true; 1237 } 1238 } 1239 return false; 1240} 1241 1242void VirtualSpaceList::retire_current_virtual_space() { 1243 assert_lock_strong(SpaceManager::expand_lock()); 1244 1245 VirtualSpaceNode* vsn = current_virtual_space(); 1246 1247 ChunkManager* cm = is_class() ? Metaspace::chunk_manager_class() : 1248 Metaspace::chunk_manager_metadata(); 1249 1250 vsn->retire(cm); 1251} 1252 1253void VirtualSpaceNode::retire(ChunkManager* chunk_manager) { 1254 DEBUG_ONLY(verify_container_count();) 1255 for (int i = (int)MediumIndex; i >= (int)ZeroIndex; --i) { 1256 ChunkIndex index = (ChunkIndex)i; 1257 size_t chunk_size = chunk_manager->size_by_index(index); 1258 1259 while (free_words_in_vs() >= chunk_size) { 1260 Metachunk* chunk = get_chunk_vs(chunk_size); 1261 assert(chunk != NULL, "allocation should have been successful"); 1262 1263 chunk_manager->return_single_chunk(index, chunk); 1264 } 1265 DEBUG_ONLY(verify_container_count();) 1266 } 1267 assert(free_words_in_vs() == 0, "should be empty now"); 1268} 1269 1270VirtualSpaceList::VirtualSpaceList(size_t word_size) : 1271 _is_class(false), 1272 _virtual_space_list(NULL), 1273 _current_virtual_space(NULL), 1274 _reserved_words(0), 1275 _committed_words(0), 1276 _virtual_space_count(0) { 1277 MutexLockerEx cl(SpaceManager::expand_lock(), 1278 Mutex::_no_safepoint_check_flag); 1279 create_new_virtual_space(word_size); 1280} 1281 1282VirtualSpaceList::VirtualSpaceList(ReservedSpace rs) : 1283 _is_class(true), 1284 _virtual_space_list(NULL), 1285 _current_virtual_space(NULL), 1286 _reserved_words(0), 1287 _committed_words(0), 1288 _virtual_space_count(0) { 1289 MutexLockerEx cl(SpaceManager::expand_lock(), 1290 Mutex::_no_safepoint_check_flag); 1291 VirtualSpaceNode* class_entry = new VirtualSpaceNode(rs); 1292 bool succeeded = class_entry->initialize(); 1293 if (succeeded) { 1294 link_vs(class_entry); 1295 } 1296} 1297 1298size_t VirtualSpaceList::free_bytes() { 1299 return virtual_space_list()->free_words_in_vs() * BytesPerWord; 1300} 1301 1302// Allocate another meta virtual space and add it to the list. 1303bool VirtualSpaceList::create_new_virtual_space(size_t vs_word_size) { 1304 assert_lock_strong(SpaceManager::expand_lock()); 1305 1306 if (is_class()) { 1307 assert(false, "We currently don't support more than one VirtualSpace for" 1308 " the compressed class space. The initialization of the" 1309 " CCS uses another code path and should not hit this path."); 1310 return false; 1311 } 1312 1313 if (vs_word_size == 0) { 1314 assert(false, "vs_word_size should always be at least _reserve_alignment large."); 1315 return false; 1316 } 1317 1318 // Reserve the space 1319 size_t vs_byte_size = vs_word_size * BytesPerWord; 1320 assert_is_aligned(vs_byte_size, Metaspace::reserve_alignment()); 1321 1322 // Allocate the meta virtual space and initialize it. 1323 VirtualSpaceNode* new_entry = new VirtualSpaceNode(vs_byte_size); 1324 if (!new_entry->initialize()) { 1325 delete new_entry; 1326 return false; 1327 } else { 1328 assert(new_entry->reserved_words() == vs_word_size, 1329 "Reserved memory size differs from requested memory size"); 1330 // ensure lock-free iteration sees fully initialized node 1331 OrderAccess::storestore(); 1332 link_vs(new_entry); 1333 return true; 1334 } 1335} 1336 1337void VirtualSpaceList::link_vs(VirtualSpaceNode* new_entry) { 1338 if (virtual_space_list() == NULL) { 1339 set_virtual_space_list(new_entry); 1340 } else { 1341 current_virtual_space()->set_next(new_entry); 1342 } 1343 set_current_virtual_space(new_entry); 1344 inc_reserved_words(new_entry->reserved_words()); 1345 inc_committed_words(new_entry->committed_words()); 1346 inc_virtual_space_count(); 1347#ifdef ASSERT 1348 new_entry->mangle(); 1349#endif 1350 if (log_is_enabled(Trace, gc, metaspace)) { 1351 Log(gc, metaspace) log; 1352 VirtualSpaceNode* vsl = current_virtual_space(); 1353 ResourceMark rm; 1354 vsl->print_on(log.trace_stream()); 1355 } 1356} 1357 1358bool VirtualSpaceList::expand_node_by(VirtualSpaceNode* node, 1359 size_t min_words, 1360 size_t preferred_words) { 1361 size_t before = node->committed_words(); 1362 1363 bool result = node->expand_by(min_words, preferred_words); 1364 1365 size_t after = node->committed_words(); 1366 1367 // after and before can be the same if the memory was pre-committed. 1368 assert(after >= before, "Inconsistency"); 1369 inc_committed_words(after - before); 1370 1371 return result; 1372} 1373 1374bool VirtualSpaceList::expand_by(size_t min_words, size_t preferred_words) { 1375 assert_is_aligned(min_words, Metaspace::commit_alignment_words()); 1376 assert_is_aligned(preferred_words, Metaspace::commit_alignment_words()); 1377 assert(min_words <= preferred_words, "Invalid arguments"); 1378 1379 if (!MetaspaceGC::can_expand(min_words, this->is_class())) { 1380 return false; 1381 } 1382 1383 size_t allowed_expansion_words = MetaspaceGC::allowed_expansion(); 1384 if (allowed_expansion_words < min_words) { 1385 return false; 1386 } 1387 1388 size_t max_expansion_words = MIN2(preferred_words, allowed_expansion_words); 1389 1390 // Commit more memory from the the current virtual space. 1391 bool vs_expanded = expand_node_by(current_virtual_space(), 1392 min_words, 1393 max_expansion_words); 1394 if (vs_expanded) { 1395 return true; 1396 } 1397 retire_current_virtual_space(); 1398 1399 // Get another virtual space. 1400 size_t grow_vs_words = MAX2((size_t)VirtualSpaceSize, preferred_words); 1401 grow_vs_words = align_up(grow_vs_words, Metaspace::reserve_alignment_words()); 1402 1403 if (create_new_virtual_space(grow_vs_words)) { 1404 if (current_virtual_space()->is_pre_committed()) { 1405 // The memory was pre-committed, so we are done here. 1406 assert(min_words <= current_virtual_space()->committed_words(), 1407 "The new VirtualSpace was pre-committed, so it" 1408 "should be large enough to fit the alloc request."); 1409 return true; 1410 } 1411 1412 return expand_node_by(current_virtual_space(), 1413 min_words, 1414 max_expansion_words); 1415 } 1416 1417 return false; 1418} 1419 1420Metachunk* VirtualSpaceList::get_new_chunk(size_t chunk_word_size, size_t suggested_commit_granularity) { 1421 1422 // Allocate a chunk out of the current virtual space. 1423 Metachunk* next = current_virtual_space()->get_chunk_vs(chunk_word_size); 1424 1425 if (next != NULL) { 1426 return next; 1427 } 1428 1429 // The expand amount is currently only determined by the requested sizes 1430 // and not how much committed memory is left in the current virtual space. 1431 1432 size_t min_word_size = align_up(chunk_word_size, Metaspace::commit_alignment_words()); 1433 size_t preferred_word_size = align_up(suggested_commit_granularity, Metaspace::commit_alignment_words()); 1434 if (min_word_size >= preferred_word_size) { 1435 // Can happen when humongous chunks are allocated. 1436 preferred_word_size = min_word_size; 1437 } 1438 1439 bool expanded = expand_by(min_word_size, preferred_word_size); 1440 if (expanded) { 1441 next = current_virtual_space()->get_chunk_vs(chunk_word_size); 1442 assert(next != NULL, "The allocation was expected to succeed after the expansion"); 1443 } 1444 1445 return next; 1446} 1447 1448void VirtualSpaceList::print_on(outputStream* st) const { 1449 VirtualSpaceListIterator iter(virtual_space_list()); 1450 while (iter.repeat()) { 1451 VirtualSpaceNode* node = iter.get_next(); 1452 node->print_on(st); 1453 } 1454} 1455 1456// MetaspaceGC methods 1457 1458// VM_CollectForMetadataAllocation is the vm operation used to GC. 1459// Within the VM operation after the GC the attempt to allocate the metadata 1460// should succeed. If the GC did not free enough space for the metaspace 1461// allocation, the HWM is increased so that another virtualspace will be 1462// allocated for the metadata. With perm gen the increase in the perm 1463// gen had bounds, MinMetaspaceExpansion and MaxMetaspaceExpansion. The 1464// metaspace policy uses those as the small and large steps for the HWM. 1465// 1466// After the GC the compute_new_size() for MetaspaceGC is called to 1467// resize the capacity of the metaspaces. The current implementation 1468// is based on the flags MinMetaspaceFreeRatio and MaxMetaspaceFreeRatio used 1469// to resize the Java heap by some GC's. New flags can be implemented 1470// if really needed. MinMetaspaceFreeRatio is used to calculate how much 1471// free space is desirable in the metaspace capacity to decide how much 1472// to increase the HWM. MaxMetaspaceFreeRatio is used to decide how much 1473// free space is desirable in the metaspace capacity before decreasing 1474// the HWM. 1475 1476// Calculate the amount to increase the high water mark (HWM). 1477// Increase by a minimum amount (MinMetaspaceExpansion) so that 1478// another expansion is not requested too soon. If that is not 1479// enough to satisfy the allocation, increase by MaxMetaspaceExpansion. 1480// If that is still not enough, expand by the size of the allocation 1481// plus some. 1482size_t MetaspaceGC::delta_capacity_until_GC(size_t bytes) { 1483 size_t min_delta = MinMetaspaceExpansion; 1484 size_t max_delta = MaxMetaspaceExpansion; 1485 size_t delta = align_up(bytes, Metaspace::commit_alignment()); 1486 1487 if (delta <= min_delta) { 1488 delta = min_delta; 1489 } else if (delta <= max_delta) { 1490 // Don't want to hit the high water mark on the next 1491 // allocation so make the delta greater than just enough 1492 // for this allocation. 1493 delta = max_delta; 1494 } else { 1495 // This allocation is large but the next ones are probably not 1496 // so increase by the minimum. 1497 delta = delta + min_delta; 1498 } 1499 1500 assert_is_aligned(delta, Metaspace::commit_alignment()); 1501 1502 return delta; 1503} 1504 1505size_t MetaspaceGC::capacity_until_GC() { 1506 size_t value = (size_t)OrderAccess::load_ptr_acquire(&_capacity_until_GC); 1507 assert(value >= MetaspaceSize, "Not initialized properly?"); 1508 return value; 1509} 1510 1511bool MetaspaceGC::inc_capacity_until_GC(size_t v, size_t* new_cap_until_GC, size_t* old_cap_until_GC) { 1512 assert_is_aligned(v, Metaspace::commit_alignment()); 1513 1514 size_t capacity_until_GC = (size_t) _capacity_until_GC; 1515 size_t new_value = capacity_until_GC + v; 1516 1517 if (new_value < capacity_until_GC) { 1518 // The addition wrapped around, set new_value to aligned max value. 1519 new_value = align_down(max_uintx, Metaspace::commit_alignment()); 1520 } 1521 1522 intptr_t expected = (intptr_t) capacity_until_GC; 1523 intptr_t actual = Atomic::cmpxchg_ptr((intptr_t) new_value, &_capacity_until_GC, expected); 1524 1525 if (expected != actual) { 1526 return false; 1527 } 1528 1529 if (new_cap_until_GC != NULL) { 1530 *new_cap_until_GC = new_value; 1531 } 1532 if (old_cap_until_GC != NULL) { 1533 *old_cap_until_GC = capacity_until_GC; 1534 } 1535 return true; 1536} 1537 1538size_t MetaspaceGC::dec_capacity_until_GC(size_t v) { 1539 assert_is_aligned(v, Metaspace::commit_alignment()); 1540 1541 return (size_t)Atomic::add_ptr(-(intptr_t)v, &_capacity_until_GC); 1542} 1543 1544void MetaspaceGC::initialize() { 1545 // Set the high-water mark to MaxMetapaceSize during VM initializaton since 1546 // we can't do a GC during initialization. 1547 _capacity_until_GC = MaxMetaspaceSize; 1548} 1549 1550void MetaspaceGC::post_initialize() { 1551 // Reset the high-water mark once the VM initialization is done. 1552 _capacity_until_GC = MAX2(MetaspaceAux::committed_bytes(), MetaspaceSize); 1553} 1554 1555bool MetaspaceGC::can_expand(size_t word_size, bool is_class) { 1556 // Check if the compressed class space is full. 1557 if (is_class && Metaspace::using_class_space()) { 1558 size_t class_committed = MetaspaceAux::committed_bytes(Metaspace::ClassType); 1559 if (class_committed + word_size * BytesPerWord > CompressedClassSpaceSize) { 1560 return false; 1561 } 1562 } 1563 1564 // Check if the user has imposed a limit on the metaspace memory. 1565 size_t committed_bytes = MetaspaceAux::committed_bytes(); 1566 if (committed_bytes + word_size * BytesPerWord > MaxMetaspaceSize) { 1567 return false; 1568 } 1569 1570 return true; 1571} 1572 1573size_t MetaspaceGC::allowed_expansion() { 1574 size_t committed_bytes = MetaspaceAux::committed_bytes(); 1575 size_t capacity_until_gc = capacity_until_GC(); 1576 1577 assert(capacity_until_gc >= committed_bytes, 1578 "capacity_until_gc: " SIZE_FORMAT " < committed_bytes: " SIZE_FORMAT, 1579 capacity_until_gc, committed_bytes); 1580 1581 size_t left_until_max = MaxMetaspaceSize - committed_bytes; 1582 size_t left_until_GC = capacity_until_gc - committed_bytes; 1583 size_t left_to_commit = MIN2(left_until_GC, left_until_max); 1584 1585 return left_to_commit / BytesPerWord; 1586} 1587 1588void MetaspaceGC::compute_new_size() { 1589 assert(_shrink_factor <= 100, "invalid shrink factor"); 1590 uint current_shrink_factor = _shrink_factor; 1591 _shrink_factor = 0; 1592 1593 // Using committed_bytes() for used_after_gc is an overestimation, since the 1594 // chunk free lists are included in committed_bytes() and the memory in an 1595 // un-fragmented chunk free list is available for future allocations. 1596 // However, if the chunk free lists becomes fragmented, then the memory may 1597 // not be available for future allocations and the memory is therefore "in use". 1598 // Including the chunk free lists in the definition of "in use" is therefore 1599 // necessary. Not including the chunk free lists can cause capacity_until_GC to 1600 // shrink below committed_bytes() and this has caused serious bugs in the past. 1601 const size_t used_after_gc = MetaspaceAux::committed_bytes(); 1602 const size_t capacity_until_GC = MetaspaceGC::capacity_until_GC(); 1603 1604 const double minimum_free_percentage = MinMetaspaceFreeRatio / 100.0; 1605 const double maximum_used_percentage = 1.0 - minimum_free_percentage; 1606 1607 const double min_tmp = used_after_gc / maximum_used_percentage; 1608 size_t minimum_desired_capacity = 1609 (size_t)MIN2(min_tmp, double(max_uintx)); 1610 // Don't shrink less than the initial generation size 1611 minimum_desired_capacity = MAX2(minimum_desired_capacity, 1612 MetaspaceSize); 1613 1614 log_trace(gc, metaspace)("MetaspaceGC::compute_new_size: "); 1615 log_trace(gc, metaspace)(" minimum_free_percentage: %6.2f maximum_used_percentage: %6.2f", 1616 minimum_free_percentage, maximum_used_percentage); 1617 log_trace(gc, metaspace)(" used_after_gc : %6.1fKB", used_after_gc / (double) K); 1618 1619 1620 size_t shrink_bytes = 0; 1621 if (capacity_until_GC < minimum_desired_capacity) { 1622 // If we have less capacity below the metaspace HWM, then 1623 // increment the HWM. 1624 size_t expand_bytes = minimum_desired_capacity - capacity_until_GC; 1625 expand_bytes = align_up(expand_bytes, Metaspace::commit_alignment()); 1626 // Don't expand unless it's significant 1627 if (expand_bytes >= MinMetaspaceExpansion) { 1628 size_t new_capacity_until_GC = 0; 1629 bool succeeded = MetaspaceGC::inc_capacity_until_GC(expand_bytes, &new_capacity_until_GC); 1630 assert(succeeded, "Should always succesfully increment HWM when at safepoint"); 1631 1632 Metaspace::tracer()->report_gc_threshold(capacity_until_GC, 1633 new_capacity_until_GC, 1634 MetaspaceGCThresholdUpdater::ComputeNewSize); 1635 log_trace(gc, metaspace)(" expanding: minimum_desired_capacity: %6.1fKB expand_bytes: %6.1fKB MinMetaspaceExpansion: %6.1fKB new metaspace HWM: %6.1fKB", 1636 minimum_desired_capacity / (double) K, 1637 expand_bytes / (double) K, 1638 MinMetaspaceExpansion / (double) K, 1639 new_capacity_until_GC / (double) K); 1640 } 1641 return; 1642 } 1643 1644 // No expansion, now see if we want to shrink 1645 // We would never want to shrink more than this 1646 assert(capacity_until_GC >= minimum_desired_capacity, 1647 SIZE_FORMAT " >= " SIZE_FORMAT, 1648 capacity_until_GC, minimum_desired_capacity); 1649 size_t max_shrink_bytes = capacity_until_GC - minimum_desired_capacity; 1650 1651 // Should shrinking be considered? 1652 if (MaxMetaspaceFreeRatio < 100) { 1653 const double maximum_free_percentage = MaxMetaspaceFreeRatio / 100.0; 1654 const double minimum_used_percentage = 1.0 - maximum_free_percentage; 1655 const double max_tmp = used_after_gc / minimum_used_percentage; 1656 size_t maximum_desired_capacity = (size_t)MIN2(max_tmp, double(max_uintx)); 1657 maximum_desired_capacity = MAX2(maximum_desired_capacity, 1658 MetaspaceSize); 1659 log_trace(gc, metaspace)(" maximum_free_percentage: %6.2f minimum_used_percentage: %6.2f", 1660 maximum_free_percentage, minimum_used_percentage); 1661 log_trace(gc, metaspace)(" minimum_desired_capacity: %6.1fKB maximum_desired_capacity: %6.1fKB", 1662 minimum_desired_capacity / (double) K, maximum_desired_capacity / (double) K); 1663 1664 assert(minimum_desired_capacity <= maximum_desired_capacity, 1665 "sanity check"); 1666 1667 if (capacity_until_GC > maximum_desired_capacity) { 1668 // Capacity too large, compute shrinking size 1669 shrink_bytes = capacity_until_GC - maximum_desired_capacity; 1670 // We don't want shrink all the way back to initSize if people call 1671 // System.gc(), because some programs do that between "phases" and then 1672 // we'd just have to grow the heap up again for the next phase. So we 1673 // damp the shrinking: 0% on the first call, 10% on the second call, 40% 1674 // on the third call, and 100% by the fourth call. But if we recompute 1675 // size without shrinking, it goes back to 0%. 1676 shrink_bytes = shrink_bytes / 100 * current_shrink_factor; 1677 1678 shrink_bytes = align_down(shrink_bytes, Metaspace::commit_alignment()); 1679 1680 assert(shrink_bytes <= max_shrink_bytes, 1681 "invalid shrink size " SIZE_FORMAT " not <= " SIZE_FORMAT, 1682 shrink_bytes, max_shrink_bytes); 1683 if (current_shrink_factor == 0) { 1684 _shrink_factor = 10; 1685 } else { 1686 _shrink_factor = MIN2(current_shrink_factor * 4, (uint) 100); 1687 } 1688 log_trace(gc, metaspace)(" shrinking: initThreshold: %.1fK maximum_desired_capacity: %.1fK", 1689 MetaspaceSize / (double) K, maximum_desired_capacity / (double) K); 1690 log_trace(gc, metaspace)(" shrink_bytes: %.1fK current_shrink_factor: %d new shrink factor: %d MinMetaspaceExpansion: %.1fK", 1691 shrink_bytes / (double) K, current_shrink_factor, _shrink_factor, MinMetaspaceExpansion / (double) K); 1692 } 1693 } 1694 1695 // Don't shrink unless it's significant 1696 if (shrink_bytes >= MinMetaspaceExpansion && 1697 ((capacity_until_GC - shrink_bytes) >= MetaspaceSize)) { 1698 size_t new_capacity_until_GC = MetaspaceGC::dec_capacity_until_GC(shrink_bytes); 1699 Metaspace::tracer()->report_gc_threshold(capacity_until_GC, 1700 new_capacity_until_GC, 1701 MetaspaceGCThresholdUpdater::ComputeNewSize); 1702 } 1703} 1704 1705// Metadebug methods 1706 1707void Metadebug::init_allocation_fail_alot_count() { 1708 if (MetadataAllocationFailALot) { 1709 _allocation_fail_alot_count = 1710 1+(long)((double)MetadataAllocationFailALotInterval*os::random()/(max_jint+1.0)); 1711 } 1712} 1713 1714#ifdef ASSERT 1715bool Metadebug::test_metadata_failure() { 1716 if (MetadataAllocationFailALot && 1717 Threads::is_vm_complete()) { 1718 if (_allocation_fail_alot_count > 0) { 1719 _allocation_fail_alot_count--; 1720 } else { 1721 log_trace(gc, metaspace, freelist)("Metadata allocation failing for MetadataAllocationFailALot"); 1722 init_allocation_fail_alot_count(); 1723 return true; 1724 } 1725 } 1726 return false; 1727} 1728#endif 1729 1730// ChunkManager methods 1731 1732size_t ChunkManager::free_chunks_total_words() { 1733 return _free_chunks_total; 1734} 1735 1736size_t ChunkManager::free_chunks_total_bytes() { 1737 return free_chunks_total_words() * BytesPerWord; 1738} 1739 1740// Update internal accounting after a chunk was added 1741void ChunkManager::account_for_added_chunk(const Metachunk* c) { 1742 assert_lock_strong(SpaceManager::expand_lock()); 1743 _free_chunks_count ++; 1744 _free_chunks_total += c->word_size(); 1745} 1746 1747// Update internal accounting after a chunk was removed 1748void ChunkManager::account_for_removed_chunk(const Metachunk* c) { 1749 assert_lock_strong(SpaceManager::expand_lock()); 1750 assert(_free_chunks_count >= 1, 1751 "ChunkManager::_free_chunks_count: about to go negative (" SIZE_FORMAT ").", _free_chunks_count); 1752 assert(_free_chunks_total >= c->word_size(), 1753 "ChunkManager::_free_chunks_total: about to go negative" 1754 "(now: " SIZE_FORMAT ", decrement value: " SIZE_FORMAT ").", _free_chunks_total, c->word_size()); 1755 _free_chunks_count --; 1756 _free_chunks_total -= c->word_size(); 1757} 1758 1759size_t ChunkManager::free_chunks_count() { 1760#ifdef ASSERT 1761 if (!UseConcMarkSweepGC && !SpaceManager::expand_lock()->is_locked()) { 1762 MutexLockerEx cl(SpaceManager::expand_lock(), 1763 Mutex::_no_safepoint_check_flag); 1764 // This lock is only needed in debug because the verification 1765 // of the _free_chunks_totals walks the list of free chunks 1766 slow_locked_verify_free_chunks_count(); 1767 } 1768#endif 1769 return _free_chunks_count; 1770} 1771 1772ChunkIndex ChunkManager::list_index(size_t size) { 1773 if (size_by_index(SpecializedIndex) == size) { 1774 return SpecializedIndex; 1775 } 1776 if (size_by_index(SmallIndex) == size) { 1777 return SmallIndex; 1778 } 1779 const size_t med_size = size_by_index(MediumIndex); 1780 if (med_size == size) { 1781 return MediumIndex; 1782 } 1783 1784 assert(size > med_size, "Not a humongous chunk"); 1785 return HumongousIndex; 1786} 1787 1788size_t ChunkManager::size_by_index(ChunkIndex index) { 1789 index_bounds_check(index); 1790 assert(index != HumongousIndex, "Do not call for humongous chunks."); 1791 return free_chunks(index)->size(); 1792} 1793 1794void ChunkManager::locked_verify_free_chunks_total() { 1795 assert_lock_strong(SpaceManager::expand_lock()); 1796 assert(sum_free_chunks() == _free_chunks_total, 1797 "_free_chunks_total " SIZE_FORMAT " is not the" 1798 " same as sum " SIZE_FORMAT, _free_chunks_total, 1799 sum_free_chunks()); 1800} 1801 1802void ChunkManager::verify_free_chunks_total() { 1803 MutexLockerEx cl(SpaceManager::expand_lock(), 1804 Mutex::_no_safepoint_check_flag); 1805 locked_verify_free_chunks_total(); 1806} 1807 1808void ChunkManager::locked_verify_free_chunks_count() { 1809 assert_lock_strong(SpaceManager::expand_lock()); 1810 assert(sum_free_chunks_count() == _free_chunks_count, 1811 "_free_chunks_count " SIZE_FORMAT " is not the" 1812 " same as sum " SIZE_FORMAT, _free_chunks_count, 1813 sum_free_chunks_count()); 1814} 1815 1816void ChunkManager::verify_free_chunks_count() { 1817#ifdef ASSERT 1818 MutexLockerEx cl(SpaceManager::expand_lock(), 1819 Mutex::_no_safepoint_check_flag); 1820 locked_verify_free_chunks_count(); 1821#endif 1822} 1823 1824void ChunkManager::verify() { 1825 MutexLockerEx cl(SpaceManager::expand_lock(), 1826 Mutex::_no_safepoint_check_flag); 1827 locked_verify(); 1828} 1829 1830void ChunkManager::locked_verify() { 1831 locked_verify_free_chunks_count(); 1832 locked_verify_free_chunks_total(); 1833} 1834 1835void ChunkManager::locked_print_free_chunks(outputStream* st) { 1836 assert_lock_strong(SpaceManager::expand_lock()); 1837 st->print_cr("Free chunk total " SIZE_FORMAT " count " SIZE_FORMAT, 1838 _free_chunks_total, _free_chunks_count); 1839} 1840 1841void ChunkManager::locked_print_sum_free_chunks(outputStream* st) { 1842 assert_lock_strong(SpaceManager::expand_lock()); 1843 st->print_cr("Sum free chunk total " SIZE_FORMAT " count " SIZE_FORMAT, 1844 sum_free_chunks(), sum_free_chunks_count()); 1845} 1846 1847ChunkList* ChunkManager::free_chunks(ChunkIndex index) { 1848 assert(index == SpecializedIndex || index == SmallIndex || index == MediumIndex, 1849 "Bad index: %d", (int)index); 1850 1851 return &_free_chunks[index]; 1852} 1853 1854// These methods that sum the free chunk lists are used in printing 1855// methods that are used in product builds. 1856size_t ChunkManager::sum_free_chunks() { 1857 assert_lock_strong(SpaceManager::expand_lock()); 1858 size_t result = 0; 1859 for (ChunkIndex i = ZeroIndex; i < NumberOfFreeLists; i = next_chunk_index(i)) { 1860 ChunkList* list = free_chunks(i); 1861 1862 if (list == NULL) { 1863 continue; 1864 } 1865 1866 result = result + list->count() * list->size(); 1867 } 1868 result = result + humongous_dictionary()->total_size(); 1869 return result; 1870} 1871 1872size_t ChunkManager::sum_free_chunks_count() { 1873 assert_lock_strong(SpaceManager::expand_lock()); 1874 size_t count = 0; 1875 for (ChunkIndex i = ZeroIndex; i < NumberOfFreeLists; i = next_chunk_index(i)) { 1876 ChunkList* list = free_chunks(i); 1877 if (list == NULL) { 1878 continue; 1879 } 1880 count = count + list->count(); 1881 } 1882 count = count + humongous_dictionary()->total_free_blocks(); 1883 return count; 1884} 1885 1886ChunkList* ChunkManager::find_free_chunks_list(size_t word_size) { 1887 ChunkIndex index = list_index(word_size); 1888 assert(index < HumongousIndex, "No humongous list"); 1889 return free_chunks(index); 1890} 1891 1892Metachunk* ChunkManager::free_chunks_get(size_t word_size) { 1893 assert_lock_strong(SpaceManager::expand_lock()); 1894 1895 slow_locked_verify(); 1896 1897 Metachunk* chunk = NULL; 1898 if (list_index(word_size) != HumongousIndex) { 1899 ChunkList* free_list = find_free_chunks_list(word_size); 1900 assert(free_list != NULL, "Sanity check"); 1901 1902 chunk = free_list->head(); 1903 1904 if (chunk == NULL) { 1905 return NULL; 1906 } 1907 1908 // Remove the chunk as the head of the list. 1909 free_list->remove_chunk(chunk); 1910 1911 log_trace(gc, metaspace, freelist)("ChunkManager::free_chunks_get: free_list " PTR_FORMAT " head " PTR_FORMAT " size " SIZE_FORMAT, 1912 p2i(free_list), p2i(chunk), chunk->word_size()); 1913 } else { 1914 chunk = humongous_dictionary()->get_chunk( 1915 word_size, 1916 FreeBlockDictionary<Metachunk>::atLeast); 1917 1918 if (chunk == NULL) { 1919 return NULL; 1920 } 1921 1922 log_debug(gc, metaspace, alloc)("Free list allocate humongous chunk size " SIZE_FORMAT " for requested size " SIZE_FORMAT " waste " SIZE_FORMAT, 1923 chunk->word_size(), word_size, chunk->word_size() - word_size); 1924 } 1925 1926 // Chunk has been removed from the chunk manager; update counters. 1927 account_for_removed_chunk(chunk); 1928 1929 // Remove it from the links to this freelist 1930 chunk->set_next(NULL); 1931 chunk->set_prev(NULL); 1932#ifdef ASSERT 1933 // Chunk is no longer on any freelist. Setting to false make container_count_slow() 1934 // work. 1935 chunk->set_is_tagged_free(false); 1936#endif 1937 chunk->container()->inc_container_count(); 1938 1939 slow_locked_verify(); 1940 return chunk; 1941} 1942 1943Metachunk* ChunkManager::chunk_freelist_allocate(size_t word_size) { 1944 assert_lock_strong(SpaceManager::expand_lock()); 1945 slow_locked_verify(); 1946 1947 // Take from the beginning of the list 1948 Metachunk* chunk = free_chunks_get(word_size); 1949 if (chunk == NULL) { 1950 return NULL; 1951 } 1952 1953 assert((word_size <= chunk->word_size()) || 1954 (list_index(chunk->word_size()) == HumongousIndex), 1955 "Non-humongous variable sized chunk"); 1956 Log(gc, metaspace, freelist) log; 1957 if (log.is_debug()) { 1958 size_t list_count; 1959 if (list_index(word_size) < HumongousIndex) { 1960 ChunkList* list = find_free_chunks_list(word_size); 1961 list_count = list->count(); 1962 } else { 1963 list_count = humongous_dictionary()->total_count(); 1964 } 1965 log.debug("ChunkManager::chunk_freelist_allocate: " PTR_FORMAT " chunk " PTR_FORMAT " size " SIZE_FORMAT " count " SIZE_FORMAT " ", 1966 p2i(this), p2i(chunk), chunk->word_size(), list_count); 1967 ResourceMark rm; 1968 locked_print_free_chunks(log.debug_stream()); 1969 } 1970 1971 return chunk; 1972} 1973 1974void ChunkManager::return_single_chunk(ChunkIndex index, Metachunk* chunk) { 1975 assert_lock_strong(SpaceManager::expand_lock()); 1976 assert(chunk != NULL, "Expected chunk."); 1977 assert(chunk->container() != NULL, "Container should have been set."); 1978 assert(chunk->is_tagged_free() == false, "Chunk should be in use."); 1979 index_bounds_check(index); 1980 1981 // Note: mangle *before* returning the chunk to the freelist or dictionary. It does not 1982 // matter for the freelist (non-humongous chunks), but the humongous chunk dictionary 1983 // keeps tree node pointers in the chunk payload area which mangle will overwrite. 1984 NOT_PRODUCT(chunk->mangle(badMetaWordVal);) 1985 1986 if (index != HumongousIndex) { 1987 // Return non-humongous chunk to freelist. 1988 ChunkList* list = free_chunks(index); 1989 assert(list->size() == chunk->word_size(), "Wrong chunk type."); 1990 list->return_chunk_at_head(chunk); 1991 log_trace(gc, metaspace, freelist)("returned one %s chunk at " PTR_FORMAT " to freelist.", 1992 chunk_size_name(index), p2i(chunk)); 1993 } else { 1994 // Return humongous chunk to dictionary. 1995 assert(chunk->word_size() > free_chunks(MediumIndex)->size(), "Wrong chunk type."); 1996 assert(chunk->word_size() % free_chunks(SpecializedIndex)->size() == 0, 1997 "Humongous chunk has wrong alignment."); 1998 _humongous_dictionary.return_chunk(chunk); 1999 log_trace(gc, metaspace, freelist)("returned one %s chunk at " PTR_FORMAT " (word size " SIZE_FORMAT ") to freelist.", 2000 chunk_size_name(index), p2i(chunk), chunk->word_size()); 2001 } 2002 chunk->container()->dec_container_count(); 2003 DEBUG_ONLY(chunk->set_is_tagged_free(true);) 2004 2005 // Chunk has been added; update counters. 2006 account_for_added_chunk(chunk); 2007 2008} 2009 2010void ChunkManager::return_chunk_list(ChunkIndex index, Metachunk* chunks) { 2011 index_bounds_check(index); 2012 if (chunks == NULL) { 2013 return; 2014 } 2015 LogTarget(Trace, gc, metaspace, freelist) log; 2016 if (log.is_enabled()) { // tracing 2017 log.print("returning list of %s chunks...", chunk_size_name(index)); 2018 } 2019 unsigned num_chunks_returned = 0; 2020 size_t size_chunks_returned = 0; 2021 Metachunk* cur = chunks; 2022 while (cur != NULL) { 2023 // Capture the next link before it is changed 2024 // by the call to return_chunk_at_head(); 2025 Metachunk* next = cur->next(); 2026 if (log.is_enabled()) { // tracing 2027 num_chunks_returned ++; 2028 size_chunks_returned += cur->word_size(); 2029 } 2030 return_single_chunk(index, cur); 2031 cur = next; 2032 } 2033 if (log.is_enabled()) { // tracing 2034 log.print("returned %u %s chunks to freelist, total word size " SIZE_FORMAT ".", 2035 num_chunks_returned, chunk_size_name(index), size_chunks_returned); 2036 if (index != HumongousIndex) { 2037 log.print("updated freelist count: " SIZE_FORMAT ".", free_chunks(index)->size()); 2038 } else { 2039 log.print("updated dictionary count " SIZE_FORMAT ".", _humongous_dictionary.total_count()); 2040 } 2041 } 2042} 2043 2044void ChunkManager::print_on(outputStream* out) const { 2045 const_cast<ChunkManager *>(this)->humongous_dictionary()->report_statistics(out); 2046} 2047 2048// SpaceManager methods 2049 2050size_t SpaceManager::adjust_initial_chunk_size(size_t requested, bool is_class_space) { 2051 size_t chunk_sizes[] = { 2052 specialized_chunk_size(is_class_space), 2053 small_chunk_size(is_class_space), 2054 medium_chunk_size(is_class_space) 2055 }; 2056 2057 // Adjust up to one of the fixed chunk sizes ... 2058 for (size_t i = 0; i < ARRAY_SIZE(chunk_sizes); i++) { 2059 if (requested <= chunk_sizes[i]) { 2060 return chunk_sizes[i]; 2061 } 2062 } 2063 2064 // ... or return the size as a humongous chunk. 2065 return requested; 2066} 2067 2068size_t SpaceManager::adjust_initial_chunk_size(size_t requested) const { 2069 return adjust_initial_chunk_size(requested, is_class()); 2070} 2071 2072size_t SpaceManager::get_initial_chunk_size(Metaspace::MetaspaceType type) const { 2073 size_t requested; 2074 2075 if (is_class()) { 2076 switch (type) { 2077 case Metaspace::BootMetaspaceType: requested = Metaspace::first_class_chunk_word_size(); break; 2078 case Metaspace::ROMetaspaceType: requested = ClassSpecializedChunk; break; 2079 case Metaspace::ReadWriteMetaspaceType: requested = ClassSpecializedChunk; break; 2080 case Metaspace::AnonymousMetaspaceType: requested = ClassSpecializedChunk; break; 2081 case Metaspace::ReflectionMetaspaceType: requested = ClassSpecializedChunk; break; 2082 default: requested = ClassSmallChunk; break; 2083 } 2084 } else { 2085 switch (type) { 2086 case Metaspace::BootMetaspaceType: requested = Metaspace::first_chunk_word_size(); break; 2087 case Metaspace::ROMetaspaceType: requested = SharedReadOnlySize / wordSize; break; 2088 case Metaspace::ReadWriteMetaspaceType: requested = SharedReadWriteSize / wordSize; break; 2089 case Metaspace::AnonymousMetaspaceType: requested = SpecializedChunk; break; 2090 case Metaspace::ReflectionMetaspaceType: requested = SpecializedChunk; break; 2091 default: requested = SmallChunk; break; 2092 } 2093 } 2094 2095 // Adjust to one of the fixed chunk sizes (unless humongous) 2096 const size_t adjusted = adjust_initial_chunk_size(requested); 2097 2098 assert(adjusted != 0, "Incorrect initial chunk size. Requested: " 2099 SIZE_FORMAT " adjusted: " SIZE_FORMAT, requested, adjusted); 2100 2101 return adjusted; 2102} 2103 2104size_t SpaceManager::sum_free_in_chunks_in_use() const { 2105 MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag); 2106 size_t free = 0; 2107 for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) { 2108 Metachunk* chunk = chunks_in_use(i); 2109 while (chunk != NULL) { 2110 free += chunk->free_word_size(); 2111 chunk = chunk->next(); 2112 } 2113 } 2114 return free; 2115} 2116 2117size_t SpaceManager::sum_waste_in_chunks_in_use() const { 2118 MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag); 2119 size_t result = 0; 2120 for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) { 2121 result += sum_waste_in_chunks_in_use(i); 2122 } 2123 2124 return result; 2125} 2126 2127size_t SpaceManager::sum_waste_in_chunks_in_use(ChunkIndex index) const { 2128 size_t result = 0; 2129 Metachunk* chunk = chunks_in_use(index); 2130 // Count the free space in all the chunk but not the 2131 // current chunk from which allocations are still being done. 2132 while (chunk != NULL) { 2133 if (chunk != current_chunk()) { 2134 result += chunk->free_word_size(); 2135 } 2136 chunk = chunk->next(); 2137 } 2138 return result; 2139} 2140 2141size_t SpaceManager::sum_capacity_in_chunks_in_use() const { 2142 // For CMS use "allocated_chunks_words()" which does not need the 2143 // Metaspace lock. For the other collectors sum over the 2144 // lists. Use both methods as a check that "allocated_chunks_words()" 2145 // is correct. That is, sum_capacity_in_chunks() is too expensive 2146 // to use in the product and allocated_chunks_words() should be used 2147 // but allow for checking that allocated_chunks_words() returns the same 2148 // value as sum_capacity_in_chunks_in_use() which is the definitive 2149 // answer. 2150 if (UseConcMarkSweepGC) { 2151 return allocated_chunks_words(); 2152 } else { 2153 MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag); 2154 size_t sum = 0; 2155 for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) { 2156 Metachunk* chunk = chunks_in_use(i); 2157 while (chunk != NULL) { 2158 sum += chunk->word_size(); 2159 chunk = chunk->next(); 2160 } 2161 } 2162 return sum; 2163 } 2164} 2165 2166size_t SpaceManager::sum_count_in_chunks_in_use() { 2167 size_t count = 0; 2168 for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) { 2169 count = count + sum_count_in_chunks_in_use(i); 2170 } 2171 2172 return count; 2173} 2174 2175size_t SpaceManager::sum_count_in_chunks_in_use(ChunkIndex i) { 2176 size_t count = 0; 2177 Metachunk* chunk = chunks_in_use(i); 2178 while (chunk != NULL) { 2179 count++; 2180 chunk = chunk->next(); 2181 } 2182 return count; 2183} 2184 2185 2186size_t SpaceManager::sum_used_in_chunks_in_use() const { 2187 MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag); 2188 size_t used = 0; 2189 for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) { 2190 Metachunk* chunk = chunks_in_use(i); 2191 while (chunk != NULL) { 2192 used += chunk->used_word_size(); 2193 chunk = chunk->next(); 2194 } 2195 } 2196 return used; 2197} 2198 2199void SpaceManager::locked_print_chunks_in_use_on(outputStream* st) const { 2200 2201 for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) { 2202 Metachunk* chunk = chunks_in_use(i); 2203 st->print("SpaceManager: %s " PTR_FORMAT, 2204 chunk_size_name(i), p2i(chunk)); 2205 if (chunk != NULL) { 2206 st->print_cr(" free " SIZE_FORMAT, 2207 chunk->free_word_size()); 2208 } else { 2209 st->cr(); 2210 } 2211 } 2212 2213 chunk_manager()->locked_print_free_chunks(st); 2214 chunk_manager()->locked_print_sum_free_chunks(st); 2215} 2216 2217size_t SpaceManager::calc_chunk_size(size_t word_size) { 2218 2219 // Decide between a small chunk and a medium chunk. Up to 2220 // _small_chunk_limit small chunks can be allocated. 2221 // After that a medium chunk is preferred. 2222 size_t chunk_word_size; 2223 if (chunks_in_use(MediumIndex) == NULL && 2224 sum_count_in_chunks_in_use(SmallIndex) < _small_chunk_limit) { 2225 chunk_word_size = (size_t) small_chunk_size(); 2226 if (word_size + Metachunk::overhead() > small_chunk_size()) { 2227 chunk_word_size = medium_chunk_size(); 2228 } 2229 } else { 2230 chunk_word_size = medium_chunk_size(); 2231 } 2232 2233 // Might still need a humongous chunk. Enforce 2234 // humongous allocations sizes to be aligned up to 2235 // the smallest chunk size. 2236 size_t if_humongous_sized_chunk = 2237 align_up(word_size + Metachunk::overhead(), 2238 smallest_chunk_size()); 2239 chunk_word_size = 2240 MAX2((size_t) chunk_word_size, if_humongous_sized_chunk); 2241 2242 assert(!SpaceManager::is_humongous(word_size) || 2243 chunk_word_size == if_humongous_sized_chunk, 2244 "Size calculation is wrong, word_size " SIZE_FORMAT 2245 " chunk_word_size " SIZE_FORMAT, 2246 word_size, chunk_word_size); 2247 Log(gc, metaspace, alloc) log; 2248 if (log.is_debug() && SpaceManager::is_humongous(word_size)) { 2249 log.debug("Metadata humongous allocation:"); 2250 log.debug(" word_size " PTR_FORMAT, word_size); 2251 log.debug(" chunk_word_size " PTR_FORMAT, chunk_word_size); 2252 log.debug(" chunk overhead " PTR_FORMAT, Metachunk::overhead()); 2253 } 2254 return chunk_word_size; 2255} 2256 2257void SpaceManager::track_metaspace_memory_usage() { 2258 if (is_init_completed()) { 2259 if (is_class()) { 2260 MemoryService::track_compressed_class_memory_usage(); 2261 } 2262 MemoryService::track_metaspace_memory_usage(); 2263 } 2264} 2265 2266MetaWord* SpaceManager::grow_and_allocate(size_t word_size) { 2267 assert(vs_list()->current_virtual_space() != NULL, 2268 "Should have been set"); 2269 assert(current_chunk() == NULL || 2270 current_chunk()->allocate(word_size) == NULL, 2271 "Don't need to expand"); 2272 MutexLockerEx cl(SpaceManager::expand_lock(), Mutex::_no_safepoint_check_flag); 2273 2274 if (log_is_enabled(Trace, gc, metaspace, freelist)) { 2275 size_t words_left = 0; 2276 size_t words_used = 0; 2277 if (current_chunk() != NULL) { 2278 words_left = current_chunk()->free_word_size(); 2279 words_used = current_chunk()->used_word_size(); 2280 } 2281 log_trace(gc, metaspace, freelist)("SpaceManager::grow_and_allocate for " SIZE_FORMAT " words " SIZE_FORMAT " words used " SIZE_FORMAT " words left", 2282 word_size, words_used, words_left); 2283 } 2284 2285 // Get another chunk 2286 size_t chunk_word_size = calc_chunk_size(word_size); 2287 Metachunk* next = get_new_chunk(chunk_word_size); 2288 2289 MetaWord* mem = NULL; 2290 2291 // If a chunk was available, add it to the in-use chunk list 2292 // and do an allocation from it. 2293 if (next != NULL) { 2294 // Add to this manager's list of chunks in use. 2295 add_chunk(next, false); 2296 mem = next->allocate(word_size); 2297 } 2298 2299 // Track metaspace memory usage statistic. 2300 track_metaspace_memory_usage(); 2301 2302 return mem; 2303} 2304 2305void SpaceManager::print_on(outputStream* st) const { 2306 2307 for (ChunkIndex i = ZeroIndex; 2308 i < NumberOfInUseLists ; 2309 i = next_chunk_index(i) ) { 2310 st->print_cr(" chunks_in_use " PTR_FORMAT " chunk size " SIZE_FORMAT, 2311 p2i(chunks_in_use(i)), 2312 chunks_in_use(i) == NULL ? 0 : chunks_in_use(i)->word_size()); 2313 } 2314 st->print_cr(" waste: Small " SIZE_FORMAT " Medium " SIZE_FORMAT 2315 " Humongous " SIZE_FORMAT, 2316 sum_waste_in_chunks_in_use(SmallIndex), 2317 sum_waste_in_chunks_in_use(MediumIndex), 2318 sum_waste_in_chunks_in_use(HumongousIndex)); 2319 // block free lists 2320 if (block_freelists() != NULL) { 2321 st->print_cr("total in block free lists " SIZE_FORMAT, 2322 block_freelists()->total_size()); 2323 } 2324} 2325 2326SpaceManager::SpaceManager(Metaspace::MetadataType mdtype, 2327 Mutex* lock) : 2328 _mdtype(mdtype), 2329 _allocated_blocks_words(0), 2330 _allocated_chunks_words(0), 2331 _allocated_chunks_count(0), 2332 _block_freelists(NULL), 2333 _lock(lock) 2334{ 2335 initialize(); 2336} 2337 2338void SpaceManager::inc_size_metrics(size_t words) { 2339 assert_lock_strong(SpaceManager::expand_lock()); 2340 // Total of allocated Metachunks and allocated Metachunks count 2341 // for each SpaceManager 2342 _allocated_chunks_words = _allocated_chunks_words + words; 2343 _allocated_chunks_count++; 2344 // Global total of capacity in allocated Metachunks 2345 MetaspaceAux::inc_capacity(mdtype(), words); 2346 // Global total of allocated Metablocks. 2347 // used_words_slow() includes the overhead in each 2348 // Metachunk so include it in the used when the 2349 // Metachunk is first added (so only added once per 2350 // Metachunk). 2351 MetaspaceAux::inc_used(mdtype(), Metachunk::overhead()); 2352} 2353 2354void SpaceManager::inc_used_metrics(size_t words) { 2355 // Add to the per SpaceManager total 2356 Atomic::add_ptr(words, &_allocated_blocks_words); 2357 // Add to the global total 2358 MetaspaceAux::inc_used(mdtype(), words); 2359} 2360 2361void SpaceManager::dec_total_from_size_metrics() { 2362 MetaspaceAux::dec_capacity(mdtype(), allocated_chunks_words()); 2363 MetaspaceAux::dec_used(mdtype(), allocated_blocks_words()); 2364 // Also deduct the overhead per Metachunk 2365 MetaspaceAux::dec_used(mdtype(), allocated_chunks_count() * Metachunk::overhead()); 2366} 2367 2368void SpaceManager::initialize() { 2369 Metadebug::init_allocation_fail_alot_count(); 2370 for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) { 2371 _chunks_in_use[i] = NULL; 2372 } 2373 _current_chunk = NULL; 2374 log_trace(gc, metaspace, freelist)("SpaceManager(): " PTR_FORMAT, p2i(this)); 2375} 2376 2377SpaceManager::~SpaceManager() { 2378 // This call this->_lock which can't be done while holding expand_lock() 2379 assert(sum_capacity_in_chunks_in_use() == allocated_chunks_words(), 2380 "sum_capacity_in_chunks_in_use() " SIZE_FORMAT 2381 " allocated_chunks_words() " SIZE_FORMAT, 2382 sum_capacity_in_chunks_in_use(), allocated_chunks_words()); 2383 2384 MutexLockerEx fcl(SpaceManager::expand_lock(), 2385 Mutex::_no_safepoint_check_flag); 2386 2387 chunk_manager()->slow_locked_verify(); 2388 2389 dec_total_from_size_metrics(); 2390 2391 Log(gc, metaspace, freelist) log; 2392 if (log.is_trace()) { 2393 log.trace("~SpaceManager(): " PTR_FORMAT, p2i(this)); 2394 ResourceMark rm; 2395 locked_print_chunks_in_use_on(log.trace_stream()); 2396 if (block_freelists() != NULL) { 2397 block_freelists()->print_on(log.trace_stream()); 2398 } 2399 } 2400 2401 // Add all the chunks in use by this space manager 2402 // to the global list of free chunks. 2403 2404 // Follow each list of chunks-in-use and add them to the 2405 // free lists. Each list is NULL terminated. 2406 2407 for (ChunkIndex i = ZeroIndex; i <= HumongousIndex; i = next_chunk_index(i)) { 2408 Metachunk* chunks = chunks_in_use(i); 2409 chunk_manager()->return_chunk_list(i, chunks); 2410 set_chunks_in_use(i, NULL); 2411 } 2412 2413 chunk_manager()->slow_locked_verify(); 2414 2415 if (_block_freelists != NULL) { 2416 delete _block_freelists; 2417 } 2418} 2419 2420void SpaceManager::deallocate(MetaWord* p, size_t word_size) { 2421 assert_lock_strong(_lock); 2422 // Allocations and deallocations are in raw_word_size 2423 size_t raw_word_size = get_allocation_word_size(word_size); 2424 // Lazily create a block_freelist 2425 if (block_freelists() == NULL) { 2426 _block_freelists = new BlockFreelist(); 2427 } 2428 block_freelists()->return_block(p, raw_word_size); 2429} 2430 2431// Adds a chunk to the list of chunks in use. 2432void SpaceManager::add_chunk(Metachunk* new_chunk, bool make_current) { 2433 2434 assert(new_chunk != NULL, "Should not be NULL"); 2435 assert(new_chunk->next() == NULL, "Should not be on a list"); 2436 2437 new_chunk->reset_empty(); 2438 2439 // Find the correct list and and set the current 2440 // chunk for that list. 2441 ChunkIndex index = chunk_manager()->list_index(new_chunk->word_size()); 2442 2443 if (index != HumongousIndex) { 2444 retire_current_chunk(); 2445 set_current_chunk(new_chunk); 2446 new_chunk->set_next(chunks_in_use(index)); 2447 set_chunks_in_use(index, new_chunk); 2448 } else { 2449 // For null class loader data and DumpSharedSpaces, the first chunk isn't 2450 // small, so small will be null. Link this first chunk as the current 2451 // chunk. 2452 if (make_current) { 2453 // Set as the current chunk but otherwise treat as a humongous chunk. 2454 set_current_chunk(new_chunk); 2455 } 2456 // Link at head. The _current_chunk only points to a humongous chunk for 2457 // the null class loader metaspace (class and data virtual space managers) 2458 // any humongous chunks so will not point to the tail 2459 // of the humongous chunks list. 2460 new_chunk->set_next(chunks_in_use(HumongousIndex)); 2461 set_chunks_in_use(HumongousIndex, new_chunk); 2462 2463 assert(new_chunk->word_size() > medium_chunk_size(), "List inconsistency"); 2464 } 2465 2466 // Add to the running sum of capacity 2467 inc_size_metrics(new_chunk->word_size()); 2468 2469 assert(new_chunk->is_empty(), "Not ready for reuse"); 2470 Log(gc, metaspace, freelist) log; 2471 if (log.is_trace()) { 2472 log.trace("SpaceManager::add_chunk: " SIZE_FORMAT ") ", sum_count_in_chunks_in_use()); 2473 ResourceMark rm; 2474 outputStream* out = log.trace_stream(); 2475 new_chunk->print_on(out); 2476 chunk_manager()->locked_print_free_chunks(out); 2477 } 2478} 2479 2480void SpaceManager::retire_current_chunk() { 2481 if (current_chunk() != NULL) { 2482 size_t remaining_words = current_chunk()->free_word_size(); 2483 if (remaining_words >= BlockFreelist::min_dictionary_size()) { 2484 MetaWord* ptr = current_chunk()->allocate(remaining_words); 2485 deallocate(ptr, remaining_words); 2486 inc_used_metrics(remaining_words); 2487 } 2488 } 2489} 2490 2491Metachunk* SpaceManager::get_new_chunk(size_t chunk_word_size) { 2492 // Get a chunk from the chunk freelist 2493 Metachunk* next = chunk_manager()->chunk_freelist_allocate(chunk_word_size); 2494 2495 if (next == NULL) { 2496 next = vs_list()->get_new_chunk(chunk_word_size, 2497 medium_chunk_bunch()); 2498 } 2499 2500 Log(gc, metaspace, alloc) log; 2501 if (log.is_debug() && next != NULL && 2502 SpaceManager::is_humongous(next->word_size())) { 2503 log.debug(" new humongous chunk word size " PTR_FORMAT, next->word_size()); 2504 } 2505 2506 return next; 2507} 2508 2509/* 2510 * The policy is to allocate up to _small_chunk_limit small chunks 2511 * after which only medium chunks are allocated. This is done to 2512 * reduce fragmentation. In some cases, this can result in a lot 2513 * of small chunks being allocated to the point where it's not 2514 * possible to expand. If this happens, there may be no medium chunks 2515 * available and OOME would be thrown. Instead of doing that, 2516 * if the allocation request size fits in a small chunk, an attempt 2517 * will be made to allocate a small chunk. 2518 */ 2519MetaWord* SpaceManager::get_small_chunk_and_allocate(size_t word_size) { 2520 size_t raw_word_size = get_allocation_word_size(word_size); 2521 2522 if (raw_word_size + Metachunk::overhead() > small_chunk_size()) { 2523 return NULL; 2524 } 2525 2526 MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag); 2527 MutexLockerEx cl1(expand_lock(), Mutex::_no_safepoint_check_flag); 2528 2529 Metachunk* chunk = chunk_manager()->chunk_freelist_allocate(small_chunk_size()); 2530 2531 MetaWord* mem = NULL; 2532 2533 if (chunk != NULL) { 2534 // Add chunk to the in-use chunk list and do an allocation from it. 2535 // Add to this manager's list of chunks in use. 2536 add_chunk(chunk, false); 2537 mem = chunk->allocate(raw_word_size); 2538 2539 inc_used_metrics(raw_word_size); 2540 2541 // Track metaspace memory usage statistic. 2542 track_metaspace_memory_usage(); 2543 } 2544 2545 return mem; 2546} 2547 2548MetaWord* SpaceManager::allocate(size_t word_size) { 2549 MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag); 2550 size_t raw_word_size = get_allocation_word_size(word_size); 2551 BlockFreelist* fl = block_freelists(); 2552 MetaWord* p = NULL; 2553 // Allocation from the dictionary is expensive in the sense that 2554 // the dictionary has to be searched for a size. Don't allocate 2555 // from the dictionary until it starts to get fat. Is this 2556 // a reasonable policy? Maybe an skinny dictionary is fast enough 2557 // for allocations. Do some profiling. JJJ 2558 if (fl != NULL && fl->total_size() > allocation_from_dictionary_limit) { 2559 p = fl->get_block(raw_word_size); 2560 } 2561 if (p == NULL) { 2562 p = allocate_work(raw_word_size); 2563 } 2564 2565 return p; 2566} 2567 2568// Returns the address of spaced allocated for "word_size". 2569// This methods does not know about blocks (Metablocks) 2570MetaWord* SpaceManager::allocate_work(size_t word_size) { 2571 assert_lock_strong(_lock); 2572#ifdef ASSERT 2573 if (Metadebug::test_metadata_failure()) { 2574 return NULL; 2575 } 2576#endif 2577 // Is there space in the current chunk? 2578 MetaWord* result = NULL; 2579 2580 // For DumpSharedSpaces, only allocate out of the current chunk which is 2581 // never null because we gave it the size we wanted. Caller reports out 2582 // of memory if this returns null. 2583 if (DumpSharedSpaces) { 2584 assert(current_chunk() != NULL, "should never happen"); 2585 inc_used_metrics(word_size); 2586 return current_chunk()->allocate(word_size); // caller handles null result 2587 } 2588 2589 if (current_chunk() != NULL) { 2590 result = current_chunk()->allocate(word_size); 2591 } 2592 2593 if (result == NULL) { 2594 result = grow_and_allocate(word_size); 2595 } 2596 2597 if (result != NULL) { 2598 inc_used_metrics(word_size); 2599 assert(result != (MetaWord*) chunks_in_use(MediumIndex), 2600 "Head of the list is being allocated"); 2601 } 2602 2603 return result; 2604} 2605 2606void SpaceManager::verify() { 2607 // If there are blocks in the dictionary, then 2608 // verification of chunks does not work since 2609 // being in the dictionary alters a chunk. 2610 if (block_freelists() != NULL && block_freelists()->total_size() == 0) { 2611 for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) { 2612 Metachunk* curr = chunks_in_use(i); 2613 while (curr != NULL) { 2614 curr->verify(); 2615 verify_chunk_size(curr); 2616 curr = curr->next(); 2617 } 2618 } 2619 } 2620} 2621 2622void SpaceManager::verify_chunk_size(Metachunk* chunk) { 2623 assert(is_humongous(chunk->word_size()) || 2624 chunk->word_size() == medium_chunk_size() || 2625 chunk->word_size() == small_chunk_size() || 2626 chunk->word_size() == specialized_chunk_size(), 2627 "Chunk size is wrong"); 2628 return; 2629} 2630 2631#ifdef ASSERT 2632void SpaceManager::verify_allocated_blocks_words() { 2633 // Verification is only guaranteed at a safepoint. 2634 assert(SafepointSynchronize::is_at_safepoint() || !Universe::is_fully_initialized(), 2635 "Verification can fail if the applications is running"); 2636 assert(allocated_blocks_words() == sum_used_in_chunks_in_use(), 2637 "allocation total is not consistent " SIZE_FORMAT 2638 " vs " SIZE_FORMAT, 2639 allocated_blocks_words(), sum_used_in_chunks_in_use()); 2640} 2641 2642#endif 2643 2644void SpaceManager::dump(outputStream* const out) const { 2645 size_t curr_total = 0; 2646 size_t waste = 0; 2647 uint i = 0; 2648 size_t used = 0; 2649 size_t capacity = 0; 2650 2651 // Add up statistics for all chunks in this SpaceManager. 2652 for (ChunkIndex index = ZeroIndex; 2653 index < NumberOfInUseLists; 2654 index = next_chunk_index(index)) { 2655 for (Metachunk* curr = chunks_in_use(index); 2656 curr != NULL; 2657 curr = curr->next()) { 2658 out->print("%d) ", i++); 2659 curr->print_on(out); 2660 curr_total += curr->word_size(); 2661 used += curr->used_word_size(); 2662 capacity += curr->word_size(); 2663 waste += curr->free_word_size() + curr->overhead();; 2664 } 2665 } 2666 2667 if (log_is_enabled(Trace, gc, metaspace, freelist)) { 2668 if (block_freelists() != NULL) block_freelists()->print_on(out); 2669 } 2670 2671 size_t free = current_chunk() == NULL ? 0 : current_chunk()->free_word_size(); 2672 // Free space isn't wasted. 2673 waste -= free; 2674 2675 out->print_cr("total of all chunks " SIZE_FORMAT " used " SIZE_FORMAT 2676 " free " SIZE_FORMAT " capacity " SIZE_FORMAT 2677 " waste " SIZE_FORMAT, curr_total, used, free, capacity, waste); 2678} 2679 2680// MetaspaceAux 2681 2682 2683size_t MetaspaceAux::_capacity_words[] = {0, 0}; 2684size_t MetaspaceAux::_used_words[] = {0, 0}; 2685 2686size_t MetaspaceAux::free_bytes(Metaspace::MetadataType mdtype) { 2687 VirtualSpaceList* list = Metaspace::get_space_list(mdtype); 2688 return list == NULL ? 0 : list->free_bytes(); 2689} 2690 2691size_t MetaspaceAux::free_bytes() { 2692 return free_bytes(Metaspace::ClassType) + free_bytes(Metaspace::NonClassType); 2693} 2694 2695void MetaspaceAux::dec_capacity(Metaspace::MetadataType mdtype, size_t words) { 2696 assert_lock_strong(SpaceManager::expand_lock()); 2697 assert(words <= capacity_words(mdtype), 2698 "About to decrement below 0: words " SIZE_FORMAT 2699 " is greater than _capacity_words[%u] " SIZE_FORMAT, 2700 words, mdtype, capacity_words(mdtype)); 2701 _capacity_words[mdtype] -= words; 2702} 2703 2704void MetaspaceAux::inc_capacity(Metaspace::MetadataType mdtype, size_t words) { 2705 assert_lock_strong(SpaceManager::expand_lock()); 2706 // Needs to be atomic 2707 _capacity_words[mdtype] += words; 2708} 2709 2710void MetaspaceAux::dec_used(Metaspace::MetadataType mdtype, size_t words) { 2711 assert(words <= used_words(mdtype), 2712 "About to decrement below 0: words " SIZE_FORMAT 2713 " is greater than _used_words[%u] " SIZE_FORMAT, 2714 words, mdtype, used_words(mdtype)); 2715 // For CMS deallocation of the Metaspaces occurs during the 2716 // sweep which is a concurrent phase. Protection by the expand_lock() 2717 // is not enough since allocation is on a per Metaspace basis 2718 // and protected by the Metaspace lock. 2719 jlong minus_words = (jlong) - (jlong) words; 2720 Atomic::add_ptr(minus_words, &_used_words[mdtype]); 2721} 2722 2723void MetaspaceAux::inc_used(Metaspace::MetadataType mdtype, size_t words) { 2724 // _used_words tracks allocations for 2725 // each piece of metadata. Those allocations are 2726 // generally done concurrently by different application 2727 // threads so must be done atomically. 2728 Atomic::add_ptr(words, &_used_words[mdtype]); 2729} 2730 2731size_t MetaspaceAux::used_bytes_slow(Metaspace::MetadataType mdtype) { 2732 size_t used = 0; 2733 ClassLoaderDataGraphMetaspaceIterator iter; 2734 while (iter.repeat()) { 2735 Metaspace* msp = iter.get_next(); 2736 // Sum allocated_blocks_words for each metaspace 2737 if (msp != NULL) { 2738 used += msp->used_words_slow(mdtype); 2739 } 2740 } 2741 return used * BytesPerWord; 2742} 2743 2744size_t MetaspaceAux::free_bytes_slow(Metaspace::MetadataType mdtype) { 2745 size_t free = 0; 2746 ClassLoaderDataGraphMetaspaceIterator iter; 2747 while (iter.repeat()) { 2748 Metaspace* msp = iter.get_next(); 2749 if (msp != NULL) { 2750 free += msp->free_words_slow(mdtype); 2751 } 2752 } 2753 return free * BytesPerWord; 2754} 2755 2756size_t MetaspaceAux::capacity_bytes_slow(Metaspace::MetadataType mdtype) { 2757 if ((mdtype == Metaspace::ClassType) && !Metaspace::using_class_space()) { 2758 return 0; 2759 } 2760 // Don't count the space in the freelists. That space will be 2761 // added to the capacity calculation as needed. 2762 size_t capacity = 0; 2763 ClassLoaderDataGraphMetaspaceIterator iter; 2764 while (iter.repeat()) { 2765 Metaspace* msp = iter.get_next(); 2766 if (msp != NULL) { 2767 capacity += msp->capacity_words_slow(mdtype); 2768 } 2769 } 2770 return capacity * BytesPerWord; 2771} 2772 2773size_t MetaspaceAux::capacity_bytes_slow() { 2774#ifdef PRODUCT 2775 // Use capacity_bytes() in PRODUCT instead of this function. 2776 guarantee(false, "Should not call capacity_bytes_slow() in the PRODUCT"); 2777#endif 2778 size_t class_capacity = capacity_bytes_slow(Metaspace::ClassType); 2779 size_t non_class_capacity = capacity_bytes_slow(Metaspace::NonClassType); 2780 assert(capacity_bytes() == class_capacity + non_class_capacity, 2781 "bad accounting: capacity_bytes() " SIZE_FORMAT 2782 " class_capacity + non_class_capacity " SIZE_FORMAT 2783 " class_capacity " SIZE_FORMAT " non_class_capacity " SIZE_FORMAT, 2784 capacity_bytes(), class_capacity + non_class_capacity, 2785 class_capacity, non_class_capacity); 2786 2787 return class_capacity + non_class_capacity; 2788} 2789 2790size_t MetaspaceAux::reserved_bytes(Metaspace::MetadataType mdtype) { 2791 VirtualSpaceList* list = Metaspace::get_space_list(mdtype); 2792 return list == NULL ? 0 : list->reserved_bytes(); 2793} 2794 2795size_t MetaspaceAux::committed_bytes(Metaspace::MetadataType mdtype) { 2796 VirtualSpaceList* list = Metaspace::get_space_list(mdtype); 2797 return list == NULL ? 0 : list->committed_bytes(); 2798} 2799 2800size_t MetaspaceAux::min_chunk_size_words() { return Metaspace::first_chunk_word_size(); } 2801 2802size_t MetaspaceAux::free_chunks_total_words(Metaspace::MetadataType mdtype) { 2803 ChunkManager* chunk_manager = Metaspace::get_chunk_manager(mdtype); 2804 if (chunk_manager == NULL) { 2805 return 0; 2806 } 2807 chunk_manager->slow_verify(); 2808 return chunk_manager->free_chunks_total_words(); 2809} 2810 2811size_t MetaspaceAux::free_chunks_total_bytes(Metaspace::MetadataType mdtype) { 2812 return free_chunks_total_words(mdtype) * BytesPerWord; 2813} 2814 2815size_t MetaspaceAux::free_chunks_total_words() { 2816 return free_chunks_total_words(Metaspace::ClassType) + 2817 free_chunks_total_words(Metaspace::NonClassType); 2818} 2819 2820size_t MetaspaceAux::free_chunks_total_bytes() { 2821 return free_chunks_total_words() * BytesPerWord; 2822} 2823 2824bool MetaspaceAux::has_chunk_free_list(Metaspace::MetadataType mdtype) { 2825 return Metaspace::get_chunk_manager(mdtype) != NULL; 2826} 2827 2828MetaspaceChunkFreeListSummary MetaspaceAux::chunk_free_list_summary(Metaspace::MetadataType mdtype) { 2829 if (!has_chunk_free_list(mdtype)) { 2830 return MetaspaceChunkFreeListSummary(); 2831 } 2832 2833 const ChunkManager* cm = Metaspace::get_chunk_manager(mdtype); 2834 return cm->chunk_free_list_summary(); 2835} 2836 2837void MetaspaceAux::print_metaspace_change(size_t prev_metadata_used) { 2838 log_info(gc, metaspace)("Metaspace: " SIZE_FORMAT "K->" SIZE_FORMAT "K(" SIZE_FORMAT "K)", 2839 prev_metadata_used/K, used_bytes()/K, reserved_bytes()/K); 2840} 2841 2842void MetaspaceAux::print_on(outputStream* out) { 2843 Metaspace::MetadataType nct = Metaspace::NonClassType; 2844 2845 out->print_cr(" Metaspace " 2846 "used " SIZE_FORMAT "K, " 2847 "capacity " SIZE_FORMAT "K, " 2848 "committed " SIZE_FORMAT "K, " 2849 "reserved " SIZE_FORMAT "K", 2850 used_bytes()/K, 2851 capacity_bytes()/K, 2852 committed_bytes()/K, 2853 reserved_bytes()/K); 2854 2855 if (Metaspace::using_class_space()) { 2856 Metaspace::MetadataType ct = Metaspace::ClassType; 2857 out->print_cr(" class space " 2858 "used " SIZE_FORMAT "K, " 2859 "capacity " SIZE_FORMAT "K, " 2860 "committed " SIZE_FORMAT "K, " 2861 "reserved " SIZE_FORMAT "K", 2862 used_bytes(ct)/K, 2863 capacity_bytes(ct)/K, 2864 committed_bytes(ct)/K, 2865 reserved_bytes(ct)/K); 2866 } 2867} 2868 2869// Print information for class space and data space separately. 2870// This is almost the same as above. 2871void MetaspaceAux::print_on(outputStream* out, Metaspace::MetadataType mdtype) { 2872 size_t free_chunks_capacity_bytes = free_chunks_total_bytes(mdtype); 2873 size_t capacity_bytes = capacity_bytes_slow(mdtype); 2874 size_t used_bytes = used_bytes_slow(mdtype); 2875 size_t free_bytes = free_bytes_slow(mdtype); 2876 size_t used_and_free = used_bytes + free_bytes + 2877 free_chunks_capacity_bytes; 2878 out->print_cr(" Chunk accounting: used in chunks " SIZE_FORMAT 2879 "K + unused in chunks " SIZE_FORMAT "K + " 2880 " capacity in free chunks " SIZE_FORMAT "K = " SIZE_FORMAT 2881 "K capacity in allocated chunks " SIZE_FORMAT "K", 2882 used_bytes / K, 2883 free_bytes / K, 2884 free_chunks_capacity_bytes / K, 2885 used_and_free / K, 2886 capacity_bytes / K); 2887 // Accounting can only be correct if we got the values during a safepoint 2888 assert(!SafepointSynchronize::is_at_safepoint() || used_and_free == capacity_bytes, "Accounting is wrong"); 2889} 2890 2891// Print total fragmentation for class metaspaces 2892void MetaspaceAux::print_class_waste(outputStream* out) { 2893 assert(Metaspace::using_class_space(), "class metaspace not used"); 2894 size_t cls_specialized_waste = 0, cls_small_waste = 0, cls_medium_waste = 0; 2895 size_t cls_specialized_count = 0, cls_small_count = 0, cls_medium_count = 0, cls_humongous_count = 0; 2896 ClassLoaderDataGraphMetaspaceIterator iter; 2897 while (iter.repeat()) { 2898 Metaspace* msp = iter.get_next(); 2899 if (msp != NULL) { 2900 cls_specialized_waste += msp->class_vsm()->sum_waste_in_chunks_in_use(SpecializedIndex); 2901 cls_specialized_count += msp->class_vsm()->sum_count_in_chunks_in_use(SpecializedIndex); 2902 cls_small_waste += msp->class_vsm()->sum_waste_in_chunks_in_use(SmallIndex); 2903 cls_small_count += msp->class_vsm()->sum_count_in_chunks_in_use(SmallIndex); 2904 cls_medium_waste += msp->class_vsm()->sum_waste_in_chunks_in_use(MediumIndex); 2905 cls_medium_count += msp->class_vsm()->sum_count_in_chunks_in_use(MediumIndex); 2906 cls_humongous_count += msp->class_vsm()->sum_count_in_chunks_in_use(HumongousIndex); 2907 } 2908 } 2909 out->print_cr(" class: " SIZE_FORMAT " specialized(s) " SIZE_FORMAT ", " 2910 SIZE_FORMAT " small(s) " SIZE_FORMAT ", " 2911 SIZE_FORMAT " medium(s) " SIZE_FORMAT ", " 2912 "large count " SIZE_FORMAT, 2913 cls_specialized_count, cls_specialized_waste, 2914 cls_small_count, cls_small_waste, 2915 cls_medium_count, cls_medium_waste, cls_humongous_count); 2916} 2917 2918// Print total fragmentation for data and class metaspaces separately 2919void MetaspaceAux::print_waste(outputStream* out) { 2920 size_t specialized_waste = 0, small_waste = 0, medium_waste = 0; 2921 size_t specialized_count = 0, small_count = 0, medium_count = 0, humongous_count = 0; 2922 2923 ClassLoaderDataGraphMetaspaceIterator iter; 2924 while (iter.repeat()) { 2925 Metaspace* msp = iter.get_next(); 2926 if (msp != NULL) { 2927 specialized_waste += msp->vsm()->sum_waste_in_chunks_in_use(SpecializedIndex); 2928 specialized_count += msp->vsm()->sum_count_in_chunks_in_use(SpecializedIndex); 2929 small_waste += msp->vsm()->sum_waste_in_chunks_in_use(SmallIndex); 2930 small_count += msp->vsm()->sum_count_in_chunks_in_use(SmallIndex); 2931 medium_waste += msp->vsm()->sum_waste_in_chunks_in_use(MediumIndex); 2932 medium_count += msp->vsm()->sum_count_in_chunks_in_use(MediumIndex); 2933 humongous_count += msp->vsm()->sum_count_in_chunks_in_use(HumongousIndex); 2934 } 2935 } 2936 out->print_cr("Total fragmentation waste (words) doesn't count free space"); 2937 out->print_cr(" data: " SIZE_FORMAT " specialized(s) " SIZE_FORMAT ", " 2938 SIZE_FORMAT " small(s) " SIZE_FORMAT ", " 2939 SIZE_FORMAT " medium(s) " SIZE_FORMAT ", " 2940 "large count " SIZE_FORMAT, 2941 specialized_count, specialized_waste, small_count, 2942 small_waste, medium_count, medium_waste, humongous_count); 2943 if (Metaspace::using_class_space()) { 2944 print_class_waste(out); 2945 } 2946} 2947 2948// Dump global metaspace things from the end of ClassLoaderDataGraph 2949void MetaspaceAux::dump(outputStream* out) { 2950 out->print_cr("All Metaspace:"); 2951 out->print("data space: "); print_on(out, Metaspace::NonClassType); 2952 out->print("class space: "); print_on(out, Metaspace::ClassType); 2953 print_waste(out); 2954} 2955 2956void MetaspaceAux::verify_free_chunks() { 2957 Metaspace::chunk_manager_metadata()->verify(); 2958 if (Metaspace::using_class_space()) { 2959 Metaspace::chunk_manager_class()->verify(); 2960 } 2961} 2962 2963void MetaspaceAux::verify_capacity() { 2964#ifdef ASSERT 2965 size_t running_sum_capacity_bytes = capacity_bytes(); 2966 // For purposes of the running sum of capacity, verify against capacity 2967 size_t capacity_in_use_bytes = capacity_bytes_slow(); 2968 assert(running_sum_capacity_bytes == capacity_in_use_bytes, 2969 "capacity_words() * BytesPerWord " SIZE_FORMAT 2970 " capacity_bytes_slow()" SIZE_FORMAT, 2971 running_sum_capacity_bytes, capacity_in_use_bytes); 2972 for (Metaspace::MetadataType i = Metaspace::ClassType; 2973 i < Metaspace:: MetadataTypeCount; 2974 i = (Metaspace::MetadataType)(i + 1)) { 2975 size_t capacity_in_use_bytes = capacity_bytes_slow(i); 2976 assert(capacity_bytes(i) == capacity_in_use_bytes, 2977 "capacity_bytes(%u) " SIZE_FORMAT 2978 " capacity_bytes_slow(%u)" SIZE_FORMAT, 2979 i, capacity_bytes(i), i, capacity_in_use_bytes); 2980 } 2981#endif 2982} 2983 2984void MetaspaceAux::verify_used() { 2985#ifdef ASSERT 2986 size_t running_sum_used_bytes = used_bytes(); 2987 // For purposes of the running sum of used, verify against used 2988 size_t used_in_use_bytes = used_bytes_slow(); 2989 assert(used_bytes() == used_in_use_bytes, 2990 "used_bytes() " SIZE_FORMAT 2991 " used_bytes_slow()" SIZE_FORMAT, 2992 used_bytes(), used_in_use_bytes); 2993 for (Metaspace::MetadataType i = Metaspace::ClassType; 2994 i < Metaspace:: MetadataTypeCount; 2995 i = (Metaspace::MetadataType)(i + 1)) { 2996 size_t used_in_use_bytes = used_bytes_slow(i); 2997 assert(used_bytes(i) == used_in_use_bytes, 2998 "used_bytes(%u) " SIZE_FORMAT 2999 " used_bytes_slow(%u)" SIZE_FORMAT, 3000 i, used_bytes(i), i, used_in_use_bytes); 3001 } 3002#endif 3003} 3004 3005void MetaspaceAux::verify_metrics() { 3006 verify_capacity(); 3007 verify_used(); 3008} 3009 3010 3011// Metaspace methods 3012 3013size_t Metaspace::_first_chunk_word_size = 0; 3014size_t Metaspace::_first_class_chunk_word_size = 0; 3015 3016size_t Metaspace::_commit_alignment = 0; 3017size_t Metaspace::_reserve_alignment = 0; 3018 3019Metaspace::Metaspace(Mutex* lock, MetaspaceType type) { 3020 initialize(lock, type); 3021} 3022 3023Metaspace::~Metaspace() { 3024 delete _vsm; 3025 if (using_class_space()) { 3026 delete _class_vsm; 3027 } 3028} 3029 3030VirtualSpaceList* Metaspace::_space_list = NULL; 3031VirtualSpaceList* Metaspace::_class_space_list = NULL; 3032 3033ChunkManager* Metaspace::_chunk_manager_metadata = NULL; 3034ChunkManager* Metaspace::_chunk_manager_class = NULL; 3035 3036#define VIRTUALSPACEMULTIPLIER 2 3037 3038#ifdef _LP64 3039static const uint64_t UnscaledClassSpaceMax = (uint64_t(max_juint) + 1); 3040 3041void Metaspace::set_narrow_klass_base_and_shift(address metaspace_base, address cds_base) { 3042 // Figure out the narrow_klass_base and the narrow_klass_shift. The 3043 // narrow_klass_base is the lower of the metaspace base and the cds base 3044 // (if cds is enabled). The narrow_klass_shift depends on the distance 3045 // between the lower base and higher address. 3046 address lower_base; 3047 address higher_address; 3048#if INCLUDE_CDS 3049 if (UseSharedSpaces) { 3050 higher_address = MAX2((address)(cds_base + FileMapInfo::shared_spaces_size()), 3051 (address)(metaspace_base + compressed_class_space_size())); 3052 lower_base = MIN2(metaspace_base, cds_base); 3053 } else 3054#endif 3055 { 3056 higher_address = metaspace_base + compressed_class_space_size(); 3057 lower_base = metaspace_base; 3058 3059 uint64_t klass_encoding_max = UnscaledClassSpaceMax << LogKlassAlignmentInBytes; 3060 // If compressed class space fits in lower 32G, we don't need a base. 3061 if (higher_address <= (address)klass_encoding_max) { 3062 lower_base = 0; // Effectively lower base is zero. 3063 } 3064 } 3065 3066 Universe::set_narrow_klass_base(lower_base); 3067 3068 if ((uint64_t)(higher_address - lower_base) <= UnscaledClassSpaceMax) { 3069 Universe::set_narrow_klass_shift(0); 3070 } else { 3071 assert(!UseSharedSpaces, "Cannot shift with UseSharedSpaces"); 3072 Universe::set_narrow_klass_shift(LogKlassAlignmentInBytes); 3073 } 3074 AOTLoader::set_narrow_klass_shift(); 3075} 3076 3077#if INCLUDE_CDS 3078// Return TRUE if the specified metaspace_base and cds_base are close enough 3079// to work with compressed klass pointers. 3080bool Metaspace::can_use_cds_with_metaspace_addr(char* metaspace_base, address cds_base) { 3081 assert(cds_base != 0 && UseSharedSpaces, "Only use with CDS"); 3082 assert(UseCompressedClassPointers, "Only use with CompressedKlassPtrs"); 3083 address lower_base = MIN2((address)metaspace_base, cds_base); 3084 address higher_address = MAX2((address)(cds_base + FileMapInfo::shared_spaces_size()), 3085 (address)(metaspace_base + compressed_class_space_size())); 3086 return ((uint64_t)(higher_address - lower_base) <= UnscaledClassSpaceMax); 3087} 3088#endif 3089 3090// Try to allocate the metaspace at the requested addr. 3091void Metaspace::allocate_metaspace_compressed_klass_ptrs(char* requested_addr, address cds_base) { 3092 assert(using_class_space(), "called improperly"); 3093 assert(UseCompressedClassPointers, "Only use with CompressedKlassPtrs"); 3094 assert(compressed_class_space_size() < KlassEncodingMetaspaceMax, 3095 "Metaspace size is too big"); 3096 assert_is_aligned(requested_addr, _reserve_alignment); 3097 assert_is_aligned(cds_base, _reserve_alignment); 3098 assert_is_aligned(compressed_class_space_size(), _reserve_alignment); 3099 3100 // Don't use large pages for the class space. 3101 bool large_pages = false; 3102 3103#if !(defined(AARCH64) || defined(AIX)) 3104 ReservedSpace metaspace_rs = ReservedSpace(compressed_class_space_size(), 3105 _reserve_alignment, 3106 large_pages, 3107 requested_addr); 3108#else // AARCH64 3109 ReservedSpace metaspace_rs; 3110 3111 // Our compressed klass pointers may fit nicely into the lower 32 3112 // bits. 3113 if ((uint64_t)requested_addr + compressed_class_space_size() < 4*G) { 3114 metaspace_rs = ReservedSpace(compressed_class_space_size(), 3115 _reserve_alignment, 3116 large_pages, 3117 requested_addr); 3118 } 3119 3120 if (! metaspace_rs.is_reserved()) { 3121 // Aarch64: Try to align metaspace so that we can decode a compressed 3122 // klass with a single MOVK instruction. We can do this iff the 3123 // compressed class base is a multiple of 4G. 3124 // Aix: Search for a place where we can find memory. If we need to load 3125 // the base, 4G alignment is helpful, too. 3126 size_t increment = AARCH64_ONLY(4*)G; 3127 for (char *a = align_up(requested_addr, increment); 3128 a < (char*)(1024*G); 3129 a += increment) { 3130 if (a == (char *)(32*G)) { 3131 // Go faster from here on. Zero-based is no longer possible. 3132 increment = 4*G; 3133 } 3134 3135#if INCLUDE_CDS 3136 if (UseSharedSpaces 3137 && ! can_use_cds_with_metaspace_addr(a, cds_base)) { 3138 // We failed to find an aligned base that will reach. Fall 3139 // back to using our requested addr. 3140 metaspace_rs = ReservedSpace(compressed_class_space_size(), 3141 _reserve_alignment, 3142 large_pages, 3143 requested_addr); 3144 break; 3145 } 3146#endif 3147 3148 metaspace_rs = ReservedSpace(compressed_class_space_size(), 3149 _reserve_alignment, 3150 large_pages, 3151 a); 3152 if (metaspace_rs.is_reserved()) 3153 break; 3154 } 3155 } 3156 3157#endif // AARCH64 3158 3159 if (!metaspace_rs.is_reserved()) { 3160#if INCLUDE_CDS 3161 if (UseSharedSpaces) { 3162 size_t increment = align_up(1*G, _reserve_alignment); 3163 3164 // Keep trying to allocate the metaspace, increasing the requested_addr 3165 // by 1GB each time, until we reach an address that will no longer allow 3166 // use of CDS with compressed klass pointers. 3167 char *addr = requested_addr; 3168 while (!metaspace_rs.is_reserved() && (addr + increment > addr) && 3169 can_use_cds_with_metaspace_addr(addr + increment, cds_base)) { 3170 addr = addr + increment; 3171 metaspace_rs = ReservedSpace(compressed_class_space_size(), 3172 _reserve_alignment, large_pages, addr); 3173 } 3174 } 3175#endif 3176 // If no successful allocation then try to allocate the space anywhere. If 3177 // that fails then OOM doom. At this point we cannot try allocating the 3178 // metaspace as if UseCompressedClassPointers is off because too much 3179 // initialization has happened that depends on UseCompressedClassPointers. 3180 // So, UseCompressedClassPointers cannot be turned off at this point. 3181 if (!metaspace_rs.is_reserved()) { 3182 metaspace_rs = ReservedSpace(compressed_class_space_size(), 3183 _reserve_alignment, large_pages); 3184 if (!metaspace_rs.is_reserved()) { 3185 vm_exit_during_initialization(err_msg("Could not allocate metaspace: " SIZE_FORMAT " bytes", 3186 compressed_class_space_size())); 3187 } 3188 } 3189 } 3190 3191 // If we got here then the metaspace got allocated. 3192 MemTracker::record_virtual_memory_type((address)metaspace_rs.base(), mtClass); 3193 3194#if INCLUDE_CDS 3195 // Verify that we can use shared spaces. Otherwise, turn off CDS. 3196 if (UseSharedSpaces && !can_use_cds_with_metaspace_addr(metaspace_rs.base(), cds_base)) { 3197 FileMapInfo::stop_sharing_and_unmap( 3198 "Could not allocate metaspace at a compatible address"); 3199 } 3200#endif 3201 set_narrow_klass_base_and_shift((address)metaspace_rs.base(), 3202 UseSharedSpaces ? (address)cds_base : 0); 3203 3204 initialize_class_space(metaspace_rs); 3205 3206 if (log_is_enabled(Trace, gc, metaspace)) { 3207 Log(gc, metaspace) log; 3208 ResourceMark rm; 3209 print_compressed_class_space(log.trace_stream(), requested_addr); 3210 } 3211} 3212 3213void Metaspace::print_compressed_class_space(outputStream* st, const char* requested_addr) { 3214 st->print_cr("Narrow klass base: " PTR_FORMAT ", Narrow klass shift: %d", 3215 p2i(Universe::narrow_klass_base()), Universe::narrow_klass_shift()); 3216 if (_class_space_list != NULL) { 3217 address base = (address)_class_space_list->current_virtual_space()->bottom(); 3218 st->print("Compressed class space size: " SIZE_FORMAT " Address: " PTR_FORMAT, 3219 compressed_class_space_size(), p2i(base)); 3220 if (requested_addr != 0) { 3221 st->print(" Req Addr: " PTR_FORMAT, p2i(requested_addr)); 3222 } 3223 st->cr(); 3224 } 3225} 3226 3227// For UseCompressedClassPointers the class space is reserved above the top of 3228// the Java heap. The argument passed in is at the base of the compressed space. 3229void Metaspace::initialize_class_space(ReservedSpace rs) { 3230 // The reserved space size may be bigger because of alignment, esp with UseLargePages 3231 assert(rs.size() >= CompressedClassSpaceSize, 3232 SIZE_FORMAT " != " SIZE_FORMAT, rs.size(), CompressedClassSpaceSize); 3233 assert(using_class_space(), "Must be using class space"); 3234 _class_space_list = new VirtualSpaceList(rs); 3235 _chunk_manager_class = new ChunkManager(ClassSpecializedChunk, ClassSmallChunk, ClassMediumChunk); 3236 3237 if (!_class_space_list->initialization_succeeded()) { 3238 vm_exit_during_initialization("Failed to setup compressed class space virtual space list."); 3239 } 3240} 3241 3242#endif 3243 3244void Metaspace::ergo_initialize() { 3245 if (DumpSharedSpaces) { 3246 // Using large pages when dumping the shared archive is currently not implemented. 3247 FLAG_SET_ERGO(bool, UseLargePagesInMetaspace, false); 3248 } 3249 3250 size_t page_size = os::vm_page_size(); 3251 if (UseLargePages && UseLargePagesInMetaspace) { 3252 page_size = os::large_page_size(); 3253 } 3254 3255 _commit_alignment = page_size; 3256 _reserve_alignment = MAX2(page_size, (size_t)os::vm_allocation_granularity()); 3257 3258 // Do not use FLAG_SET_ERGO to update MaxMetaspaceSize, since this will 3259 // override if MaxMetaspaceSize was set on the command line or not. 3260 // This information is needed later to conform to the specification of the 3261 // java.lang.management.MemoryUsage API. 3262 // 3263 // Ideally, we would be able to set the default value of MaxMetaspaceSize in 3264 // globals.hpp to the aligned value, but this is not possible, since the 3265 // alignment depends on other flags being parsed. 3266 MaxMetaspaceSize = align_down_bounded(MaxMetaspaceSize, _reserve_alignment); 3267 3268 if (MetaspaceSize > MaxMetaspaceSize) { 3269 MetaspaceSize = MaxMetaspaceSize; 3270 } 3271 3272 MetaspaceSize = align_down_bounded(MetaspaceSize, _commit_alignment); 3273 3274 assert(MetaspaceSize <= MaxMetaspaceSize, "MetaspaceSize should be limited by MaxMetaspaceSize"); 3275 3276 MinMetaspaceExpansion = align_down_bounded(MinMetaspaceExpansion, _commit_alignment); 3277 MaxMetaspaceExpansion = align_down_bounded(MaxMetaspaceExpansion, _commit_alignment); 3278 3279 CompressedClassSpaceSize = align_down_bounded(CompressedClassSpaceSize, _reserve_alignment); 3280 set_compressed_class_space_size(CompressedClassSpaceSize); 3281} 3282 3283void Metaspace::global_initialize() { 3284 MetaspaceGC::initialize(); 3285 3286 // Initialize the alignment for shared spaces. 3287 int max_alignment = os::vm_allocation_granularity(); 3288 size_t cds_total = 0; 3289 3290 MetaspaceShared::set_max_alignment(max_alignment); 3291 3292 if (DumpSharedSpaces) { 3293#if INCLUDE_CDS 3294 MetaspaceShared::estimate_regions_size(); 3295 3296 SharedReadOnlySize = align_up(SharedReadOnlySize, max_alignment); 3297 SharedReadWriteSize = align_up(SharedReadWriteSize, max_alignment); 3298 SharedMiscDataSize = align_up(SharedMiscDataSize, max_alignment); 3299 SharedMiscCodeSize = align_up(SharedMiscCodeSize, max_alignment); 3300 3301 // Initialize with the sum of the shared space sizes. The read-only 3302 // and read write metaspace chunks will be allocated out of this and the 3303 // remainder is the misc code and data chunks. 3304 cds_total = FileMapInfo::shared_spaces_size(); 3305 cds_total = align_up(cds_total, _reserve_alignment); 3306 _space_list = new VirtualSpaceList(cds_total/wordSize); 3307 _chunk_manager_metadata = new ChunkManager(SpecializedChunk, SmallChunk, MediumChunk); 3308 3309 if (!_space_list->initialization_succeeded()) { 3310 vm_exit_during_initialization("Unable to dump shared archive.", NULL); 3311 } 3312 3313#ifdef _LP64 3314 if (cds_total + compressed_class_space_size() > UnscaledClassSpaceMax) { 3315 vm_exit_during_initialization("Unable to dump shared archive.", 3316 err_msg("Size of archive (" SIZE_FORMAT ") + compressed class space (" 3317 SIZE_FORMAT ") == total (" SIZE_FORMAT ") is larger than compressed " 3318 "klass limit: " UINT64_FORMAT, cds_total, compressed_class_space_size(), 3319 cds_total + compressed_class_space_size(), UnscaledClassSpaceMax)); 3320 } 3321 3322 // Set the compressed klass pointer base so that decoding of these pointers works 3323 // properly when creating the shared archive. 3324 assert(UseCompressedOops && UseCompressedClassPointers, 3325 "UseCompressedOops and UseCompressedClassPointers must be set"); 3326 Universe::set_narrow_klass_base((address)_space_list->current_virtual_space()->bottom()); 3327 log_develop_trace(gc, metaspace)("Setting_narrow_klass_base to Address: " PTR_FORMAT, 3328 p2i(_space_list->current_virtual_space()->bottom())); 3329 3330 Universe::set_narrow_klass_shift(0); 3331#endif // _LP64 3332#endif // INCLUDE_CDS 3333 } else { 3334#if INCLUDE_CDS 3335 if (UseSharedSpaces) { 3336 // If using shared space, open the file that contains the shared space 3337 // and map in the memory before initializing the rest of metaspace (so 3338 // the addresses don't conflict) 3339 address cds_address = NULL; 3340 FileMapInfo* mapinfo = new FileMapInfo(); 3341 3342 // Open the shared archive file, read and validate the header. If 3343 // initialization fails, shared spaces [UseSharedSpaces] are 3344 // disabled and the file is closed. 3345 // Map in spaces now also 3346 if (mapinfo->initialize() && MetaspaceShared::map_shared_spaces(mapinfo)) { 3347 cds_total = FileMapInfo::shared_spaces_size(); 3348 cds_address = (address)mapinfo->header()->region_addr(0); 3349#ifdef _LP64 3350 if (using_class_space()) { 3351 char* cds_end = (char*)(cds_address + cds_total); 3352 cds_end = align_up(cds_end, _reserve_alignment); 3353 // If UseCompressedClassPointers is set then allocate the metaspace area 3354 // above the heap and above the CDS area (if it exists). 3355 allocate_metaspace_compressed_klass_ptrs(cds_end, cds_address); 3356 // Map the shared string space after compressed pointers 3357 // because it relies on compressed class pointers setting to work 3358 mapinfo->map_string_regions(); 3359 } 3360#endif // _LP64 3361 } else { 3362 assert(!mapinfo->is_open() && !UseSharedSpaces, 3363 "archive file not closed or shared spaces not disabled."); 3364 } 3365 } 3366#endif // INCLUDE_CDS 3367 3368#ifdef _LP64 3369 if (!UseSharedSpaces && using_class_space()) { 3370 char* base = (char*)align_up(Universe::heap()->reserved_region().end(), _reserve_alignment); 3371 allocate_metaspace_compressed_klass_ptrs(base, 0); 3372 } 3373#endif // _LP64 3374 3375 // Initialize these before initializing the VirtualSpaceList 3376 _first_chunk_word_size = InitialBootClassLoaderMetaspaceSize / BytesPerWord; 3377 _first_chunk_word_size = align_word_size_up(_first_chunk_word_size); 3378 // Make the first class chunk bigger than a medium chunk so it's not put 3379 // on the medium chunk list. The next chunk will be small and progress 3380 // from there. This size calculated by -version. 3381 _first_class_chunk_word_size = MIN2((size_t)MediumChunk*6, 3382 (CompressedClassSpaceSize/BytesPerWord)*2); 3383 _first_class_chunk_word_size = align_word_size_up(_first_class_chunk_word_size); 3384 // Arbitrarily set the initial virtual space to a multiple 3385 // of the boot class loader size. 3386 size_t word_size = VIRTUALSPACEMULTIPLIER * _first_chunk_word_size; 3387 word_size = align_up(word_size, Metaspace::reserve_alignment_words()); 3388 3389 // Initialize the list of virtual spaces. 3390 _space_list = new VirtualSpaceList(word_size); 3391 _chunk_manager_metadata = new ChunkManager(SpecializedChunk, SmallChunk, MediumChunk); 3392 3393 if (!_space_list->initialization_succeeded()) { 3394 vm_exit_during_initialization("Unable to setup metadata virtual space list.", NULL); 3395 } 3396 } 3397 3398 _tracer = new MetaspaceTracer(); 3399} 3400 3401void Metaspace::post_initialize() { 3402 MetaspaceGC::post_initialize(); 3403} 3404 3405void Metaspace::initialize_first_chunk(MetaspaceType type, MetadataType mdtype) { 3406 Metachunk* chunk = get_initialization_chunk(type, mdtype); 3407 if (chunk != NULL) { 3408 // Add to this manager's list of chunks in use and current_chunk(). 3409 get_space_manager(mdtype)->add_chunk(chunk, true); 3410 } 3411} 3412 3413Metachunk* Metaspace::get_initialization_chunk(MetaspaceType type, MetadataType mdtype) { 3414 size_t chunk_word_size = get_space_manager(mdtype)->get_initial_chunk_size(type); 3415 3416 // Get a chunk from the chunk freelist 3417 Metachunk* chunk = get_chunk_manager(mdtype)->chunk_freelist_allocate(chunk_word_size); 3418 3419 if (chunk == NULL) { 3420 chunk = get_space_list(mdtype)->get_new_chunk(chunk_word_size, 3421 get_space_manager(mdtype)->medium_chunk_bunch()); 3422 } 3423 3424 // For dumping shared archive, report error if allocation has failed. 3425 if (DumpSharedSpaces && chunk == NULL) { 3426 report_insufficient_metaspace(MetaspaceAux::committed_bytes() + chunk_word_size * BytesPerWord); 3427 } 3428 3429 return chunk; 3430} 3431 3432void Metaspace::verify_global_initialization() { 3433 assert(space_list() != NULL, "Metadata VirtualSpaceList has not been initialized"); 3434 assert(chunk_manager_metadata() != NULL, "Metadata ChunkManager has not been initialized"); 3435 3436 if (using_class_space()) { 3437 assert(class_space_list() != NULL, "Class VirtualSpaceList has not been initialized"); 3438 assert(chunk_manager_class() != NULL, "Class ChunkManager has not been initialized"); 3439 } 3440} 3441 3442void Metaspace::initialize(Mutex* lock, MetaspaceType type) { 3443 verify_global_initialization(); 3444 3445 // Allocate SpaceManager for metadata objects. 3446 _vsm = new SpaceManager(NonClassType, lock); 3447 3448 if (using_class_space()) { 3449 // Allocate SpaceManager for classes. 3450 _class_vsm = new SpaceManager(ClassType, lock); 3451 } 3452 3453 MutexLockerEx cl(SpaceManager::expand_lock(), Mutex::_no_safepoint_check_flag); 3454 3455 // Allocate chunk for metadata objects 3456 initialize_first_chunk(type, NonClassType); 3457 3458 // Allocate chunk for class metadata objects 3459 if (using_class_space()) { 3460 initialize_first_chunk(type, ClassType); 3461 } 3462 3463 _alloc_record_head = NULL; 3464 _alloc_record_tail = NULL; 3465} 3466 3467size_t Metaspace::align_word_size_up(size_t word_size) { 3468 size_t byte_size = word_size * wordSize; 3469 return ReservedSpace::allocation_align_size_up(byte_size) / wordSize; 3470} 3471 3472MetaWord* Metaspace::allocate(size_t word_size, MetadataType mdtype) { 3473 // DumpSharedSpaces doesn't use class metadata area (yet) 3474 // Also, don't use class_vsm() unless UseCompressedClassPointers is true. 3475 if (is_class_space_allocation(mdtype)) { 3476 return class_vsm()->allocate(word_size); 3477 } else { 3478 return vsm()->allocate(word_size); 3479 } 3480} 3481 3482MetaWord* Metaspace::expand_and_allocate(size_t word_size, MetadataType mdtype) { 3483 size_t delta_bytes = MetaspaceGC::delta_capacity_until_GC(word_size * BytesPerWord); 3484 assert(delta_bytes > 0, "Must be"); 3485 3486 size_t before = 0; 3487 size_t after = 0; 3488 MetaWord* res; 3489 bool incremented; 3490 3491 // Each thread increments the HWM at most once. Even if the thread fails to increment 3492 // the HWM, an allocation is still attempted. This is because another thread must then 3493 // have incremented the HWM and therefore the allocation might still succeed. 3494 do { 3495 incremented = MetaspaceGC::inc_capacity_until_GC(delta_bytes, &after, &before); 3496 res = allocate(word_size, mdtype); 3497 } while (!incremented && res == NULL); 3498 3499 if (incremented) { 3500 tracer()->report_gc_threshold(before, after, 3501 MetaspaceGCThresholdUpdater::ExpandAndAllocate); 3502 log_trace(gc, metaspace)("Increase capacity to GC from " SIZE_FORMAT " to " SIZE_FORMAT, before, after); 3503 } 3504 3505 return res; 3506} 3507 3508// Space allocated in the Metaspace. This may 3509// be across several metadata virtual spaces. 3510char* Metaspace::bottom() const { 3511 assert(DumpSharedSpaces, "only useful and valid for dumping shared spaces"); 3512 return (char*)vsm()->current_chunk()->bottom(); 3513} 3514 3515size_t Metaspace::used_words_slow(MetadataType mdtype) const { 3516 if (mdtype == ClassType) { 3517 return using_class_space() ? class_vsm()->sum_used_in_chunks_in_use() : 0; 3518 } else { 3519 return vsm()->sum_used_in_chunks_in_use(); // includes overhead! 3520 } 3521} 3522 3523size_t Metaspace::free_words_slow(MetadataType mdtype) const { 3524 if (mdtype == ClassType) { 3525 return using_class_space() ? class_vsm()->sum_free_in_chunks_in_use() : 0; 3526 } else { 3527 return vsm()->sum_free_in_chunks_in_use(); 3528 } 3529} 3530 3531// Space capacity in the Metaspace. It includes 3532// space in the list of chunks from which allocations 3533// have been made. Don't include space in the global freelist and 3534// in the space available in the dictionary which 3535// is already counted in some chunk. 3536size_t Metaspace::capacity_words_slow(MetadataType mdtype) const { 3537 if (mdtype == ClassType) { 3538 return using_class_space() ? class_vsm()->sum_capacity_in_chunks_in_use() : 0; 3539 } else { 3540 return vsm()->sum_capacity_in_chunks_in_use(); 3541 } 3542} 3543 3544size_t Metaspace::used_bytes_slow(MetadataType mdtype) const { 3545 return used_words_slow(mdtype) * BytesPerWord; 3546} 3547 3548size_t Metaspace::capacity_bytes_slow(MetadataType mdtype) const { 3549 return capacity_words_slow(mdtype) * BytesPerWord; 3550} 3551 3552size_t Metaspace::allocated_blocks_bytes() const { 3553 return vsm()->allocated_blocks_bytes() + 3554 (using_class_space() ? class_vsm()->allocated_blocks_bytes() : 0); 3555} 3556 3557size_t Metaspace::allocated_chunks_bytes() const { 3558 return vsm()->allocated_chunks_bytes() + 3559 (using_class_space() ? class_vsm()->allocated_chunks_bytes() : 0); 3560} 3561 3562void Metaspace::deallocate(MetaWord* ptr, size_t word_size, bool is_class) { 3563 assert(!SafepointSynchronize::is_at_safepoint() 3564 || Thread::current()->is_VM_thread(), "should be the VM thread"); 3565 3566 if (DumpSharedSpaces && log_is_enabled(Info, cds)) { 3567 record_deallocation(ptr, vsm()->get_allocation_word_size(word_size)); 3568 } 3569 3570 MutexLockerEx ml(vsm()->lock(), Mutex::_no_safepoint_check_flag); 3571 3572 if (is_class && using_class_space()) { 3573 class_vsm()->deallocate(ptr, word_size); 3574 } else { 3575 vsm()->deallocate(ptr, word_size); 3576 } 3577} 3578 3579 3580MetaWord* Metaspace::allocate(ClassLoaderData* loader_data, size_t word_size, 3581 bool read_only, MetaspaceObj::Type type, TRAPS) { 3582 if (HAS_PENDING_EXCEPTION) { 3583 assert(false, "Should not allocate with exception pending"); 3584 return NULL; // caller does a CHECK_NULL too 3585 } 3586 3587 assert(loader_data != NULL, "Should never pass around a NULL loader_data. " 3588 "ClassLoaderData::the_null_class_loader_data() should have been used."); 3589 3590 // Allocate in metaspaces without taking out a lock, because it deadlocks 3591 // with the SymbolTable_lock. Dumping is single threaded for now. We'll have 3592 // to revisit this for application class data sharing. 3593 if (DumpSharedSpaces) { 3594 assert(type > MetaspaceObj::UnknownType && type < MetaspaceObj::_number_of_types, "sanity"); 3595 Metaspace* space = read_only ? loader_data->ro_metaspace() : loader_data->rw_metaspace(); 3596 MetaWord* result = space->allocate(word_size, NonClassType); 3597 if (result == NULL) { 3598 report_out_of_shared_space(read_only ? SharedReadOnly : SharedReadWrite); 3599 } 3600 if (log_is_enabled(Info, cds)) { 3601 space->record_allocation(result, type, space->vsm()->get_allocation_word_size(word_size)); 3602 } 3603 3604 // Zero initialize. 3605 Copy::fill_to_words((HeapWord*)result, word_size, 0); 3606 3607 return result; 3608 } 3609 3610 MetadataType mdtype = (type == MetaspaceObj::ClassType) ? ClassType : NonClassType; 3611 3612 // Try to allocate metadata. 3613 MetaWord* result = loader_data->metaspace_non_null()->allocate(word_size, mdtype); 3614 3615 if (result == NULL) { 3616 tracer()->report_metaspace_allocation_failure(loader_data, word_size, type, mdtype); 3617 3618 // Allocation failed. 3619 if (is_init_completed()) { 3620 // Only start a GC if the bootstrapping has completed. 3621 3622 // Try to clean out some memory and retry. 3623 result = Universe::heap()->collector_policy()->satisfy_failed_metadata_allocation( 3624 loader_data, word_size, mdtype); 3625 } 3626 } 3627 3628 if (result == NULL) { 3629 SpaceManager* sm; 3630 if (is_class_space_allocation(mdtype)) { 3631 sm = loader_data->metaspace_non_null()->class_vsm(); 3632 } else { 3633 sm = loader_data->metaspace_non_null()->vsm(); 3634 } 3635 3636 result = sm->get_small_chunk_and_allocate(word_size); 3637 3638 if (result == NULL) { 3639 report_metadata_oome(loader_data, word_size, type, mdtype, CHECK_NULL); 3640 } 3641 } 3642 3643 // Zero initialize. 3644 Copy::fill_to_words((HeapWord*)result, word_size, 0); 3645 3646 return result; 3647} 3648 3649size_t Metaspace::class_chunk_size(size_t word_size) { 3650 assert(using_class_space(), "Has to use class space"); 3651 return class_vsm()->calc_chunk_size(word_size); 3652} 3653 3654void Metaspace::report_metadata_oome(ClassLoaderData* loader_data, size_t word_size, MetaspaceObj::Type type, MetadataType mdtype, TRAPS) { 3655 tracer()->report_metadata_oom(loader_data, word_size, type, mdtype); 3656 3657 // If result is still null, we are out of memory. 3658 Log(gc, metaspace, freelist) log; 3659 if (log.is_info()) { 3660 log.info("Metaspace (%s) allocation failed for size " SIZE_FORMAT, 3661 is_class_space_allocation(mdtype) ? "class" : "data", word_size); 3662 ResourceMark rm; 3663 outputStream* out = log.info_stream(); 3664 if (loader_data->metaspace_or_null() != NULL) { 3665 loader_data->dump(out); 3666 } 3667 MetaspaceAux::dump(out); 3668 } 3669 3670 bool out_of_compressed_class_space = false; 3671 if (is_class_space_allocation(mdtype)) { 3672 Metaspace* metaspace = loader_data->metaspace_non_null(); 3673 out_of_compressed_class_space = 3674 MetaspaceAux::committed_bytes(Metaspace::ClassType) + 3675 (metaspace->class_chunk_size(word_size) * BytesPerWord) > 3676 CompressedClassSpaceSize; 3677 } 3678 3679 // -XX:+HeapDumpOnOutOfMemoryError and -XX:OnOutOfMemoryError support 3680 const char* space_string = out_of_compressed_class_space ? 3681 "Compressed class space" : "Metaspace"; 3682 3683 report_java_out_of_memory(space_string); 3684 3685 if (JvmtiExport::should_post_resource_exhausted()) { 3686 JvmtiExport::post_resource_exhausted( 3687 JVMTI_RESOURCE_EXHAUSTED_OOM_ERROR, 3688 space_string); 3689 } 3690 3691 if (!is_init_completed()) { 3692 vm_exit_during_initialization("OutOfMemoryError", space_string); 3693 } 3694 3695 if (out_of_compressed_class_space) { 3696 THROW_OOP(Universe::out_of_memory_error_class_metaspace()); 3697 } else { 3698 THROW_OOP(Universe::out_of_memory_error_metaspace()); 3699 } 3700} 3701 3702const char* Metaspace::metadata_type_name(Metaspace::MetadataType mdtype) { 3703 switch (mdtype) { 3704 case Metaspace::ClassType: return "Class"; 3705 case Metaspace::NonClassType: return "Metadata"; 3706 default: 3707 assert(false, "Got bad mdtype: %d", (int) mdtype); 3708 return NULL; 3709 } 3710} 3711 3712void Metaspace::record_allocation(void* ptr, MetaspaceObj::Type type, size_t word_size) { 3713 assert(DumpSharedSpaces, "sanity"); 3714 3715 int byte_size = (int)word_size * wordSize; 3716 AllocRecord *rec = new AllocRecord((address)ptr, type, byte_size); 3717 3718 if (_alloc_record_head == NULL) { 3719 _alloc_record_head = _alloc_record_tail = rec; 3720 } else if (_alloc_record_tail->_ptr + _alloc_record_tail->_byte_size == (address)ptr) { 3721 _alloc_record_tail->_next = rec; 3722 _alloc_record_tail = rec; 3723 } else { 3724 // slow linear search, but this doesn't happen that often, and only when dumping 3725 for (AllocRecord *old = _alloc_record_head; old; old = old->_next) { 3726 if (old->_ptr == ptr) { 3727 assert(old->_type == MetaspaceObj::DeallocatedType, "sanity"); 3728 int remain_bytes = old->_byte_size - byte_size; 3729 assert(remain_bytes >= 0, "sanity"); 3730 old->_type = type; 3731 3732 if (remain_bytes == 0) { 3733 delete(rec); 3734 } else { 3735 address remain_ptr = address(ptr) + byte_size; 3736 rec->_ptr = remain_ptr; 3737 rec->_byte_size = remain_bytes; 3738 rec->_type = MetaspaceObj::DeallocatedType; 3739 rec->_next = old->_next; 3740 old->_byte_size = byte_size; 3741 old->_next = rec; 3742 } 3743 return; 3744 } 3745 } 3746 assert(0, "reallocating a freed pointer that was not recorded"); 3747 } 3748} 3749 3750void Metaspace::record_deallocation(void* ptr, size_t word_size) { 3751 assert(DumpSharedSpaces, "sanity"); 3752 3753 for (AllocRecord *rec = _alloc_record_head; rec; rec = rec->_next) { 3754 if (rec->_ptr == ptr) { 3755 assert(rec->_byte_size == (int)word_size * wordSize, "sanity"); 3756 rec->_type = MetaspaceObj::DeallocatedType; 3757 return; 3758 } 3759 } 3760 3761 assert(0, "deallocating a pointer that was not recorded"); 3762} 3763 3764void Metaspace::iterate(Metaspace::AllocRecordClosure *closure) { 3765 assert(DumpSharedSpaces, "unimplemented for !DumpSharedSpaces"); 3766 3767 address last_addr = (address)bottom(); 3768 3769 for (AllocRecord *rec = _alloc_record_head; rec; rec = rec->_next) { 3770 address ptr = rec->_ptr; 3771 if (last_addr < ptr) { 3772 closure->doit(last_addr, MetaspaceObj::UnknownType, ptr - last_addr); 3773 } 3774 closure->doit(ptr, rec->_type, rec->_byte_size); 3775 last_addr = ptr + rec->_byte_size; 3776 } 3777 3778 address top = ((address)bottom()) + used_bytes_slow(Metaspace::NonClassType); 3779 if (last_addr < top) { 3780 closure->doit(last_addr, MetaspaceObj::UnknownType, top - last_addr); 3781 } 3782} 3783 3784void Metaspace::purge(MetadataType mdtype) { 3785 get_space_list(mdtype)->purge(get_chunk_manager(mdtype)); 3786} 3787 3788void Metaspace::purge() { 3789 MutexLockerEx cl(SpaceManager::expand_lock(), 3790 Mutex::_no_safepoint_check_flag); 3791 purge(NonClassType); 3792 if (using_class_space()) { 3793 purge(ClassType); 3794 } 3795} 3796 3797void Metaspace::print_on(outputStream* out) const { 3798 // Print both class virtual space counts and metaspace. 3799 if (Verbose) { 3800 vsm()->print_on(out); 3801 if (using_class_space()) { 3802 class_vsm()->print_on(out); 3803 } 3804 } 3805} 3806 3807bool Metaspace::contains(const void* ptr) { 3808 if (UseSharedSpaces && MetaspaceShared::is_in_shared_space(ptr)) { 3809 return true; 3810 } 3811 return contains_non_shared(ptr); 3812} 3813 3814bool Metaspace::contains_non_shared(const void* ptr) { 3815 if (using_class_space() && get_space_list(ClassType)->contains(ptr)) { 3816 return true; 3817 } 3818 3819 return get_space_list(NonClassType)->contains(ptr); 3820} 3821 3822void Metaspace::verify() { 3823 vsm()->verify(); 3824 if (using_class_space()) { 3825 class_vsm()->verify(); 3826 } 3827} 3828 3829void Metaspace::dump(outputStream* const out) const { 3830 out->print_cr("\nVirtual space manager: " INTPTR_FORMAT, p2i(vsm())); 3831 vsm()->dump(out); 3832 if (using_class_space()) { 3833 out->print_cr("\nClass space manager: " INTPTR_FORMAT, p2i(class_vsm())); 3834 class_vsm()->dump(out); 3835 } 3836} 3837 3838/////////////// Unit tests /////////////// 3839 3840#ifndef PRODUCT 3841 3842class TestMetaspaceAuxTest : AllStatic { 3843 public: 3844 static void test_reserved() { 3845 size_t reserved = MetaspaceAux::reserved_bytes(); 3846 3847 assert(reserved > 0, "assert"); 3848 3849 size_t committed = MetaspaceAux::committed_bytes(); 3850 assert(committed <= reserved, "assert"); 3851 3852 size_t reserved_metadata = MetaspaceAux::reserved_bytes(Metaspace::NonClassType); 3853 assert(reserved_metadata > 0, "assert"); 3854 assert(reserved_metadata <= reserved, "assert"); 3855 3856 if (UseCompressedClassPointers) { 3857 size_t reserved_class = MetaspaceAux::reserved_bytes(Metaspace::ClassType); 3858 assert(reserved_class > 0, "assert"); 3859 assert(reserved_class < reserved, "assert"); 3860 } 3861 } 3862 3863 static void test_committed() { 3864 size_t committed = MetaspaceAux::committed_bytes(); 3865 3866 assert(committed > 0, "assert"); 3867 3868 size_t reserved = MetaspaceAux::reserved_bytes(); 3869 assert(committed <= reserved, "assert"); 3870 3871 size_t committed_metadata = MetaspaceAux::committed_bytes(Metaspace::NonClassType); 3872 assert(committed_metadata > 0, "assert"); 3873 assert(committed_metadata <= committed, "assert"); 3874 3875 if (UseCompressedClassPointers) { 3876 size_t committed_class = MetaspaceAux::committed_bytes(Metaspace::ClassType); 3877 assert(committed_class > 0, "assert"); 3878 assert(committed_class < committed, "assert"); 3879 } 3880 } 3881 3882 static void test_virtual_space_list_large_chunk() { 3883 VirtualSpaceList* vs_list = new VirtualSpaceList(os::vm_allocation_granularity()); 3884 MutexLockerEx cl(SpaceManager::expand_lock(), Mutex::_no_safepoint_check_flag); 3885 // A size larger than VirtualSpaceSize (256k) and add one page to make it _not_ be 3886 // vm_allocation_granularity aligned on Windows. 3887 size_t large_size = (size_t)(2*256*K + (os::vm_page_size()/BytesPerWord)); 3888 large_size += (os::vm_page_size()/BytesPerWord); 3889 vs_list->get_new_chunk(large_size, 0); 3890 } 3891 3892 static void test() { 3893 test_reserved(); 3894 test_committed(); 3895 test_virtual_space_list_large_chunk(); 3896 } 3897}; 3898 3899void TestMetaspaceAux_test() { 3900 TestMetaspaceAuxTest::test(); 3901} 3902 3903class TestVirtualSpaceNodeTest { 3904 static void chunk_up(size_t words_left, size_t& num_medium_chunks, 3905 size_t& num_small_chunks, 3906 size_t& num_specialized_chunks) { 3907 num_medium_chunks = words_left / MediumChunk; 3908 words_left = words_left % MediumChunk; 3909 3910 num_small_chunks = words_left / SmallChunk; 3911 words_left = words_left % SmallChunk; 3912 // how many specialized chunks can we get? 3913 num_specialized_chunks = words_left / SpecializedChunk; 3914 assert(words_left % SpecializedChunk == 0, "should be nothing left"); 3915 } 3916 3917 public: 3918 static void test() { 3919 MutexLockerEx ml(SpaceManager::expand_lock(), Mutex::_no_safepoint_check_flag); 3920 const size_t vsn_test_size_words = MediumChunk * 4; 3921 const size_t vsn_test_size_bytes = vsn_test_size_words * BytesPerWord; 3922 3923 // The chunk sizes must be multiples of eachother, or this will fail 3924 STATIC_ASSERT(MediumChunk % SmallChunk == 0); 3925 STATIC_ASSERT(SmallChunk % SpecializedChunk == 0); 3926 3927 { // No committed memory in VSN 3928 ChunkManager cm(SpecializedChunk, SmallChunk, MediumChunk); 3929 VirtualSpaceNode vsn(vsn_test_size_bytes); 3930 vsn.initialize(); 3931 vsn.retire(&cm); 3932 assert(cm.sum_free_chunks_count() == 0, "did not commit any memory in the VSN"); 3933 } 3934 3935 { // All of VSN is committed, half is used by chunks 3936 ChunkManager cm(SpecializedChunk, SmallChunk, MediumChunk); 3937 VirtualSpaceNode vsn(vsn_test_size_bytes); 3938 vsn.initialize(); 3939 vsn.expand_by(vsn_test_size_words, vsn_test_size_words); 3940 vsn.get_chunk_vs(MediumChunk); 3941 vsn.get_chunk_vs(MediumChunk); 3942 vsn.retire(&cm); 3943 assert(cm.sum_free_chunks_count() == 2, "should have been memory left for 2 medium chunks"); 3944 assert(cm.sum_free_chunks() == 2*MediumChunk, "sizes should add up"); 3945 } 3946 3947 const size_t page_chunks = 4 * (size_t)os::vm_page_size() / BytesPerWord; 3948 // This doesn't work for systems with vm_page_size >= 16K. 3949 if (page_chunks < MediumChunk) { 3950 // 4 pages of VSN is committed, some is used by chunks 3951 ChunkManager cm(SpecializedChunk, SmallChunk, MediumChunk); 3952 VirtualSpaceNode vsn(vsn_test_size_bytes); 3953 3954 vsn.initialize(); 3955 vsn.expand_by(page_chunks, page_chunks); 3956 vsn.get_chunk_vs(SmallChunk); 3957 vsn.get_chunk_vs(SpecializedChunk); 3958 vsn.retire(&cm); 3959 3960 // committed - used = words left to retire 3961 const size_t words_left = page_chunks - SmallChunk - SpecializedChunk; 3962 3963 size_t num_medium_chunks, num_small_chunks, num_spec_chunks; 3964 chunk_up(words_left, num_medium_chunks, num_small_chunks, num_spec_chunks); 3965 3966 assert(num_medium_chunks == 0, "should not get any medium chunks"); 3967 assert(cm.sum_free_chunks_count() == (num_small_chunks + num_spec_chunks), "should be space for 3 chunks"); 3968 assert(cm.sum_free_chunks() == words_left, "sizes should add up"); 3969 } 3970 3971 { // Half of VSN is committed, a humongous chunk is used 3972 ChunkManager cm(SpecializedChunk, SmallChunk, MediumChunk); 3973 VirtualSpaceNode vsn(vsn_test_size_bytes); 3974 vsn.initialize(); 3975 vsn.expand_by(MediumChunk * 2, MediumChunk * 2); 3976 vsn.get_chunk_vs(MediumChunk + SpecializedChunk); // Humongous chunks will be aligned up to MediumChunk + SpecializedChunk 3977 vsn.retire(&cm); 3978 3979 const size_t words_left = MediumChunk * 2 - (MediumChunk + SpecializedChunk); 3980 size_t num_medium_chunks, num_small_chunks, num_spec_chunks; 3981 chunk_up(words_left, num_medium_chunks, num_small_chunks, num_spec_chunks); 3982 3983 assert(num_medium_chunks == 0, "should not get any medium chunks"); 3984 assert(cm.sum_free_chunks_count() == (num_small_chunks + num_spec_chunks), "should be space for 3 chunks"); 3985 assert(cm.sum_free_chunks() == words_left, "sizes should add up"); 3986 } 3987 3988 } 3989 3990#define assert_is_available_positive(word_size) \ 3991 assert(vsn.is_available(word_size), \ 3992 #word_size ": " PTR_FORMAT " bytes were not available in " \ 3993 "VirtualSpaceNode [" PTR_FORMAT ", " PTR_FORMAT ")", \ 3994 (uintptr_t)(word_size * BytesPerWord), p2i(vsn.bottom()), p2i(vsn.end())); 3995 3996#define assert_is_available_negative(word_size) \ 3997 assert(!vsn.is_available(word_size), \ 3998 #word_size ": " PTR_FORMAT " bytes should not be available in " \ 3999 "VirtualSpaceNode [" PTR_FORMAT ", " PTR_FORMAT ")", \ 4000 (uintptr_t)(word_size * BytesPerWord), p2i(vsn.bottom()), p2i(vsn.end())); 4001 4002 static void test_is_available_positive() { 4003 // Reserve some memory. 4004 VirtualSpaceNode vsn(os::vm_allocation_granularity()); 4005 assert(vsn.initialize(), "Failed to setup VirtualSpaceNode"); 4006 4007 // Commit some memory. 4008 size_t commit_word_size = os::vm_allocation_granularity() / BytesPerWord; 4009 bool expanded = vsn.expand_by(commit_word_size, commit_word_size); 4010 assert(expanded, "Failed to commit"); 4011 4012 // Check that is_available accepts the committed size. 4013 assert_is_available_positive(commit_word_size); 4014 4015 // Check that is_available accepts half the committed size. 4016 size_t expand_word_size = commit_word_size / 2; 4017 assert_is_available_positive(expand_word_size); 4018 } 4019 4020 static void test_is_available_negative() { 4021 // Reserve some memory. 4022 VirtualSpaceNode vsn(os::vm_allocation_granularity()); 4023 assert(vsn.initialize(), "Failed to setup VirtualSpaceNode"); 4024 4025 // Commit some memory. 4026 size_t commit_word_size = os::vm_allocation_granularity() / BytesPerWord; 4027 bool expanded = vsn.expand_by(commit_word_size, commit_word_size); 4028 assert(expanded, "Failed to commit"); 4029 4030 // Check that is_available doesn't accept a too large size. 4031 size_t two_times_commit_word_size = commit_word_size * 2; 4032 assert_is_available_negative(two_times_commit_word_size); 4033 } 4034 4035 static void test_is_available_overflow() { 4036 // Reserve some memory. 4037 VirtualSpaceNode vsn(os::vm_allocation_granularity()); 4038 assert(vsn.initialize(), "Failed to setup VirtualSpaceNode"); 4039 4040 // Commit some memory. 4041 size_t commit_word_size = os::vm_allocation_granularity() / BytesPerWord; 4042 bool expanded = vsn.expand_by(commit_word_size, commit_word_size); 4043 assert(expanded, "Failed to commit"); 4044 4045 // Calculate a size that will overflow the virtual space size. 4046 void* virtual_space_max = (void*)(uintptr_t)-1; 4047 size_t bottom_to_max = pointer_delta(virtual_space_max, vsn.bottom(), 1); 4048 size_t overflow_size = bottom_to_max + BytesPerWord; 4049 size_t overflow_word_size = overflow_size / BytesPerWord; 4050 4051 // Check that is_available can handle the overflow. 4052 assert_is_available_negative(overflow_word_size); 4053 } 4054 4055 static void test_is_available() { 4056 TestVirtualSpaceNodeTest::test_is_available_positive(); 4057 TestVirtualSpaceNodeTest::test_is_available_negative(); 4058 TestVirtualSpaceNodeTest::test_is_available_overflow(); 4059 } 4060}; 4061 4062void TestVirtualSpaceNode_test() { 4063 TestVirtualSpaceNodeTest::test(); 4064 TestVirtualSpaceNodeTest::test_is_available(); 4065} 4066 4067// The following test is placed here instead of a gtest / unittest file 4068// because the ChunkManager class is only available in this file. 4069void ChunkManager_test_list_index() { 4070 ChunkManager manager(ClassSpecializedChunk, ClassSmallChunk, ClassMediumChunk); 4071 4072 // Test previous bug where a query for a humongous class metachunk, 4073 // incorrectly matched the non-class medium metachunk size. 4074 { 4075 assert(MediumChunk > ClassMediumChunk, "Precondition for test"); 4076 4077 ChunkIndex index = manager.list_index(MediumChunk); 4078 4079 assert(index == HumongousIndex, 4080 "Requested size is larger than ClassMediumChunk," 4081 " so should return HumongousIndex. Got index: %d", (int)index); 4082 } 4083 4084 // Check the specified sizes as well. 4085 { 4086 ChunkIndex index = manager.list_index(ClassSpecializedChunk); 4087 assert(index == SpecializedIndex, "Wrong index returned. Got index: %d", (int)index); 4088 } 4089 { 4090 ChunkIndex index = manager.list_index(ClassSmallChunk); 4091 assert(index == SmallIndex, "Wrong index returned. Got index: %d", (int)index); 4092 } 4093 { 4094 ChunkIndex index = manager.list_index(ClassMediumChunk); 4095 assert(index == MediumIndex, "Wrong index returned. Got index: %d", (int)index); 4096 } 4097 { 4098 ChunkIndex index = manager.list_index(ClassMediumChunk + 1); 4099 assert(index == HumongousIndex, "Wrong index returned. Got index: %d", (int)index); 4100 } 4101} 4102 4103#endif // !PRODUCT 4104 4105#ifdef ASSERT 4106 4107// ChunkManagerReturnTest stresses taking/returning chunks from the ChunkManager. It takes and 4108// returns chunks from/to the ChunkManager while keeping track of the expected ChunkManager 4109// content. 4110class ChunkManagerReturnTestImpl { 4111 4112 VirtualSpaceNode _vsn; 4113 ChunkManager _cm; 4114 4115 // The expected content of the chunk manager. 4116 unsigned _chunks_in_chunkmanager; 4117 size_t _words_in_chunkmanager; 4118 4119 // A fixed size pool of chunks. Chunks may be in the chunk manager (free) or not (in use). 4120 static const int num_chunks = 256; 4121 Metachunk* _pool[num_chunks]; 4122 4123 // Helper, return a random position into the chunk pool. 4124 static int get_random_position() { 4125 return os::random() % num_chunks; 4126 } 4127 4128 // Asserts that ChunkManager counters match expectations. 4129 void assert_counters() { 4130 assert(_vsn.container_count() == num_chunks - _chunks_in_chunkmanager, "vsn counter mismatch."); 4131 assert(_cm.free_chunks_count() == _chunks_in_chunkmanager, "cm counter mismatch."); 4132 assert(_cm.free_chunks_total_words() == _words_in_chunkmanager, "cm counter mismatch."); 4133 } 4134 4135 // Get a random chunk size. Equal chance to get spec/med/small chunk size or 4136 // a humongous chunk size. The latter itself is random in the range of [med+spec..4*med). 4137 size_t get_random_chunk_size() { 4138 const size_t sizes [] = { SpecializedChunk, SmallChunk, MediumChunk }; 4139 const int rand = os::random() % 4; 4140 if (rand < 3) { 4141 return sizes[rand]; 4142 } else { 4143 // Note: this affects the max. size of space (see _vsn initialization in ctor). 4144 return align_up(MediumChunk + 1 + (os::random() % (MediumChunk * 4)), SpecializedChunk); 4145 } 4146 } 4147 4148 // Starting at pool index <start>+1, find the next chunk tagged as either free or in use, depending 4149 // on <is_free>. Search wraps. Returns its position, or -1 if no matching chunk was found. 4150 int next_matching_chunk(int start, bool is_free) const { 4151 assert(start >= 0 && start < num_chunks, "invalid parameter"); 4152 int pos = start; 4153 do { 4154 if (++pos == num_chunks) { 4155 pos = 0; 4156 } 4157 if (_pool[pos]->is_tagged_free() == is_free) { 4158 return pos; 4159 } 4160 } while (pos != start); 4161 return -1; 4162 } 4163 4164 // A structure to keep information about a chunk list including which 4165 // chunks are part of this list. This is needed to keep information about a chunk list 4166 // we will to return to the ChunkManager, because the original list will be destroyed. 4167 struct AChunkList { 4168 Metachunk* head; 4169 Metachunk* all[num_chunks]; 4170 size_t size; 4171 int num; 4172 ChunkIndex index; 4173 }; 4174 4175 // Assemble, from the in-use chunks (not in the chunk manager) in the pool, 4176 // a random chunk list of max. length <list_size> of chunks with the same 4177 // ChunkIndex (chunk size). 4178 // Returns false if list cannot be assembled. List is returned in the <out> 4179 // structure. Returned list may be smaller than <list_size>. 4180 bool assemble_random_chunklist(AChunkList* out, int list_size) { 4181 // Choose a random in-use chunk from the pool... 4182 const int headpos = next_matching_chunk(get_random_position(), false); 4183 if (headpos == -1) { 4184 return false; 4185 } 4186 Metachunk* const head = _pool[headpos]; 4187 out->all[0] = head; 4188 assert(head->is_tagged_free() == false, "Chunk state mismatch"); 4189 // ..then go from there, chain it up with up to list_size - 1 number of other 4190 // in-use chunks of the same index. 4191 const ChunkIndex index = _cm.list_index(head->word_size()); 4192 int num_added = 1; 4193 size_t size_added = head->word_size(); 4194 int pos = headpos; 4195 Metachunk* tail = head; 4196 do { 4197 pos = next_matching_chunk(pos, false); 4198 if (pos != headpos) { 4199 Metachunk* c = _pool[pos]; 4200 assert(c->is_tagged_free() == false, "Chunk state mismatch"); 4201 if (index == _cm.list_index(c->word_size())) { 4202 tail->set_next(c); 4203 c->set_prev(tail); 4204 tail = c; 4205 out->all[num_added] = c; 4206 num_added ++; 4207 size_added += c->word_size(); 4208 } 4209 } 4210 } while (num_added < list_size && pos != headpos); 4211 out->head = head; 4212 out->index = index; 4213 out->size = size_added; 4214 out->num = num_added; 4215 return true; 4216 } 4217 4218 // Take a single random chunk from the ChunkManager. 4219 bool take_single_random_chunk_from_chunkmanager() { 4220 assert_counters(); 4221 _cm.locked_verify(); 4222 int pos = next_matching_chunk(get_random_position(), true); 4223 if (pos == -1) { 4224 return false; 4225 } 4226 Metachunk* c = _pool[pos]; 4227 assert(c->is_tagged_free(), "Chunk state mismatch"); 4228 // Note: instead of using ChunkManager::remove_chunk on this one chunk, we call 4229 // ChunkManager::free_chunks_get() with this chunk's word size. We really want 4230 // to exercise ChunkManager::free_chunks_get() because that one gets called for 4231 // normal chunk allocation. 4232 Metachunk* c2 = _cm.free_chunks_get(c->word_size()); 4233 assert(c2 != NULL, "Unexpected."); 4234 assert(!c2->is_tagged_free(), "Chunk state mismatch"); 4235 assert(c2->next() == NULL && c2->prev() == NULL, "Chunk should be outside of a list."); 4236 _chunks_in_chunkmanager --; 4237 _words_in_chunkmanager -= c->word_size(); 4238 assert_counters(); 4239 _cm.locked_verify(); 4240 return true; 4241 } 4242 4243 // Returns a single random chunk to the chunk manager. Returns false if that 4244 // was not possible (all chunks are already in the chunk manager). 4245 bool return_single_random_chunk_to_chunkmanager() { 4246 assert_counters(); 4247 _cm.locked_verify(); 4248 int pos = next_matching_chunk(get_random_position(), false); 4249 if (pos == -1) { 4250 return false; 4251 } 4252 Metachunk* c = _pool[pos]; 4253 assert(c->is_tagged_free() == false, "wrong chunk information"); 4254 _cm.return_single_chunk(_cm.list_index(c->word_size()), c); 4255 _chunks_in_chunkmanager ++; 4256 _words_in_chunkmanager += c->word_size(); 4257 assert(c->is_tagged_free() == true, "wrong chunk information"); 4258 assert_counters(); 4259 _cm.locked_verify(); 4260 return true; 4261 } 4262 4263 // Return a random chunk list to the chunk manager. Returns the length of the 4264 // returned list. 4265 int return_random_chunk_list_to_chunkmanager(int list_size) { 4266 assert_counters(); 4267 _cm.locked_verify(); 4268 AChunkList aChunkList; 4269 if (!assemble_random_chunklist(&aChunkList, list_size)) { 4270 return 0; 4271 } 4272 // Before returning chunks are returned, they should be tagged in use. 4273 for (int i = 0; i < aChunkList.num; i ++) { 4274 assert(!aChunkList.all[i]->is_tagged_free(), "chunk state mismatch."); 4275 } 4276 _cm.return_chunk_list(aChunkList.index, aChunkList.head); 4277 _chunks_in_chunkmanager += aChunkList.num; 4278 _words_in_chunkmanager += aChunkList.size; 4279 // After all chunks are returned, check that they are now tagged free. 4280 for (int i = 0; i < aChunkList.num; i ++) { 4281 assert(aChunkList.all[i]->is_tagged_free(), "chunk state mismatch."); 4282 } 4283 assert_counters(); 4284 _cm.locked_verify(); 4285 return aChunkList.num; 4286 } 4287 4288public: 4289 4290 ChunkManagerReturnTestImpl() 4291 : _vsn(align_up(MediumChunk * num_chunks * 5 * sizeof(MetaWord), Metaspace::reserve_alignment())) 4292 , _cm(SpecializedChunk, SmallChunk, MediumChunk) 4293 , _chunks_in_chunkmanager(0) 4294 , _words_in_chunkmanager(0) 4295 { 4296 MutexLockerEx ml(SpaceManager::expand_lock(), Mutex::_no_safepoint_check_flag); 4297 // Allocate virtual space and allocate random chunks. Keep these chunks in the _pool. These chunks are 4298 // "in use", because not yet added to any chunk manager. 4299 _vsn.initialize(); 4300 _vsn.expand_by(_vsn.reserved_words(), _vsn.reserved_words()); 4301 for (int i = 0; i < num_chunks; i ++) { 4302 const size_t size = get_random_chunk_size(); 4303 _pool[i] = _vsn.get_chunk_vs(size); 4304 assert(_pool[i] != NULL, "allocation failed"); 4305 } 4306 assert_counters(); 4307 _cm.locked_verify(); 4308 } 4309 4310 // Test entry point. 4311 // Return some chunks to the chunk manager (return phase). Take some chunks out (take phase). Repeat. 4312 // Chunks are choosen randomly. Number of chunks to return or taken are choosen randomly, but affected 4313 // by the <phase_length_factor> argument: a factor of 0.0 will cause the test to quickly alternate between 4314 // returning and taking, whereas a factor of 1.0 will take/return all chunks from/to the 4315 // chunks manager, thereby emptying or filling it completely. 4316 void do_test(float phase_length_factor) { 4317 MutexLockerEx ml(SpaceManager::expand_lock(), Mutex::_no_safepoint_check_flag); 4318 assert_counters(); 4319 // Execute n operations, and operation being the move of a single chunk to/from the chunk manager. 4320 const int num_max_ops = num_chunks * 100; 4321 int num_ops = num_max_ops; 4322 const int average_phase_length = (int)(phase_length_factor * num_chunks); 4323 int num_ops_until_switch = MAX2(1, (average_phase_length + os::random() % 8 - 4)); 4324 bool return_phase = true; 4325 while (num_ops > 0) { 4326 int chunks_moved = 0; 4327 if (return_phase) { 4328 // Randomly switch between returning a single chunk or a random length chunk list. 4329 if (os::random() % 2 == 0) { 4330 if (return_single_random_chunk_to_chunkmanager()) { 4331 chunks_moved = 1; 4332 } 4333 } else { 4334 const int list_length = MAX2(1, (os::random() % num_ops_until_switch)); 4335 chunks_moved = return_random_chunk_list_to_chunkmanager(list_length); 4336 } 4337 } else { 4338 // Breath out. 4339 if (take_single_random_chunk_from_chunkmanager()) { 4340 chunks_moved = 1; 4341 } 4342 } 4343 num_ops -= chunks_moved; 4344 num_ops_until_switch -= chunks_moved; 4345 if (chunks_moved == 0 || num_ops_until_switch <= 0) { 4346 return_phase = !return_phase; 4347 num_ops_until_switch = MAX2(1, (average_phase_length + os::random() % 8 - 4)); 4348 } 4349 } 4350 } 4351}; 4352 4353void* setup_chunkmanager_returntests() { 4354 ChunkManagerReturnTestImpl* p = new ChunkManagerReturnTestImpl(); 4355 return p; 4356} 4357 4358void teardown_chunkmanager_returntests(void* p) { 4359 delete (ChunkManagerReturnTestImpl*) p; 4360} 4361 4362void run_chunkmanager_returntests(void* p, float phase_length) { 4363 ChunkManagerReturnTestImpl* test = (ChunkManagerReturnTestImpl*) p; 4364 test->do_test(phase_length); 4365} 4366 4367// The following test is placed here instead of a gtest / unittest file 4368// because the ChunkManager class is only available in this file. 4369class SpaceManagerTest : AllStatic { 4370 friend void SpaceManager_test_adjust_initial_chunk_size(); 4371 4372 static void test_adjust_initial_chunk_size(bool is_class) { 4373 const size_t smallest = SpaceManager::smallest_chunk_size(is_class); 4374 const size_t normal = SpaceManager::small_chunk_size(is_class); 4375 const size_t medium = SpaceManager::medium_chunk_size(is_class); 4376 4377#define test_adjust_initial_chunk_size(value, expected, is_class_value) \ 4378 do { \ 4379 size_t v = value; \ 4380 size_t e = expected; \ 4381 assert(SpaceManager::adjust_initial_chunk_size(v, (is_class_value)) == e, \ 4382 "Expected: " SIZE_FORMAT " got: " SIZE_FORMAT, e, v); \ 4383 } while (0) 4384 4385 // Smallest (specialized) 4386 test_adjust_initial_chunk_size(1, smallest, is_class); 4387 test_adjust_initial_chunk_size(smallest - 1, smallest, is_class); 4388 test_adjust_initial_chunk_size(smallest, smallest, is_class); 4389 4390 // Small 4391 test_adjust_initial_chunk_size(smallest + 1, normal, is_class); 4392 test_adjust_initial_chunk_size(normal - 1, normal, is_class); 4393 test_adjust_initial_chunk_size(normal, normal, is_class); 4394 4395 // Medium 4396 test_adjust_initial_chunk_size(normal + 1, medium, is_class); 4397 test_adjust_initial_chunk_size(medium - 1, medium, is_class); 4398 test_adjust_initial_chunk_size(medium, medium, is_class); 4399 4400 // Humongous 4401 test_adjust_initial_chunk_size(medium + 1, medium + 1, is_class); 4402 4403#undef test_adjust_initial_chunk_size 4404 } 4405 4406 static void test_adjust_initial_chunk_size() { 4407 test_adjust_initial_chunk_size(false); 4408 test_adjust_initial_chunk_size(true); 4409 } 4410}; 4411 4412void SpaceManager_test_adjust_initial_chunk_size() { 4413 SpaceManagerTest::test_adjust_initial_chunk_size(); 4414} 4415 4416#endif // ASSERT 4417