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/align.hpp" 50 #include "utilities/copy.hpp" 51 #include "utilities/debug.hpp" 52 #include "utilities/macros.hpp" 53 54 typedef BinaryTreeDictionary<Metablock, FreeList<Metablock> > BlockTreeDictionary; 55 typedef BinaryTreeDictionary<Metachunk, FreeList<Metachunk> > ChunkTreeDictionary; 56 57 // Set this constant to enable slow integrity checking of the free chunk lists 58 const bool metaspace_slow_verify = false; 59 60 size_t const allocation_from_dictionary_limit = 4 * K; 61 62 MetaWord* last_allocated = 0; 63 64 size_t Metaspace::_compressed_class_space_size; 65 const MetaspaceTracer* Metaspace::_tracer = NULL; 66 67 // Used in declarations in SpaceManager and ChunkManager 68 enum ChunkIndex { 69 ZeroIndex = 0, 70 SpecializedIndex = ZeroIndex, 71 SmallIndex = SpecializedIndex + 1, 72 MediumIndex = SmallIndex + 1, 73 HumongousIndex = MediumIndex + 1, 74 NumberOfFreeLists = 3, 75 NumberOfInUseLists = 4 76 }; 77 78 // Helper, returns a descriptive name for the given index. 79 static const char* chunk_size_name(ChunkIndex index) { 80 switch (index) { 81 case SpecializedIndex: 82 return "specialized"; 83 case SmallIndex: 84 return "small"; 85 case MediumIndex: 86 return "medium"; 87 case HumongousIndex: 88 return "humongous"; 89 default: 90 return "Invalid index"; 91 } 92 } 93 94 enum ChunkSizes { // in words. 95 ClassSpecializedChunk = 128, 96 SpecializedChunk = 128, 97 ClassSmallChunk = 256, 98 SmallChunk = 512, 99 ClassMediumChunk = 4 * K, 100 MediumChunk = 8 * K 101 }; 102 103 static ChunkIndex next_chunk_index(ChunkIndex i) { 104 assert(i < NumberOfInUseLists, "Out of bound"); 105 return (ChunkIndex) (i+1); 106 } 107 108 volatile intptr_t MetaspaceGC::_capacity_until_GC = 0; 109 uint MetaspaceGC::_shrink_factor = 0; 110 bool MetaspaceGC::_should_concurrent_collect = false; 111 112 typedef class FreeList<Metachunk> ChunkList; 113 114 // Manages the global free lists of chunks. 115 class ChunkManager : public CHeapObj<mtInternal> { 116 friend class TestVirtualSpaceNodeTest; 117 118 // Free list of chunks of different sizes. 119 // SpecializedChunk 120 // SmallChunk 121 // MediumChunk 122 ChunkList _free_chunks[NumberOfFreeLists]; 123 124 // Return non-humongous chunk list by its index. 125 ChunkList* free_chunks(ChunkIndex index); 126 127 // Returns non-humongous chunk list for the given chunk word size. 128 ChunkList* find_free_chunks_list(size_t word_size); 129 130 // HumongousChunk 131 ChunkTreeDictionary _humongous_dictionary; 132 133 // Returns the humongous chunk dictionary. 134 ChunkTreeDictionary* humongous_dictionary() { 135 return &_humongous_dictionary; 136 } 137 138 // Size, in metaspace words, of all chunks managed by this ChunkManager 139 size_t _free_chunks_total; 140 // Number of chunks in this ChunkManager 141 size_t _free_chunks_count; 142 143 // Update counters after a chunk was added or removed removed. 144 void account_for_added_chunk(const Metachunk* c); 145 void account_for_removed_chunk(const Metachunk* c); 146 147 // Debug support 148 149 size_t sum_free_chunks(); 150 size_t sum_free_chunks_count(); 151 152 void locked_verify_free_chunks_total(); 153 void slow_locked_verify_free_chunks_total() { 154 if (metaspace_slow_verify) { 155 locked_verify_free_chunks_total(); 156 } 157 } 158 void locked_verify_free_chunks_count(); 159 void slow_locked_verify_free_chunks_count() { 160 if (metaspace_slow_verify) { 161 locked_verify_free_chunks_count(); 162 } 163 } 164 void verify_free_chunks_count(); 165 166 public: 167 168 ChunkManager(size_t specialized_size, size_t small_size, size_t medium_size) 169 : _free_chunks_total(0), _free_chunks_count(0) { 170 _free_chunks[SpecializedIndex].set_size(specialized_size); 171 _free_chunks[SmallIndex].set_size(small_size); 172 _free_chunks[MediumIndex].set_size(medium_size); 173 } 174 175 // add or delete (return) a chunk to the global freelist. 176 Metachunk* chunk_freelist_allocate(size_t word_size); 177 178 // Map a size to a list index assuming that there are lists 179 // for special, small, medium, and humongous chunks. 180 ChunkIndex list_index(size_t size); 181 182 // Map a given index to the chunk size. 183 size_t size_by_index(ChunkIndex index); 184 185 // Take a chunk from the ChunkManager. The chunk is expected to be in 186 // the chunk manager (the freelist if non-humongous, the dictionary if 187 // humongous). 188 void remove_chunk(Metachunk* chunk); 189 190 // Return a single chunk of type index to the ChunkManager. 191 void return_single_chunk(ChunkIndex index, Metachunk* chunk); 192 193 // Add the simple linked list of chunks to the freelist of chunks 194 // of type index. 195 void return_chunk_list(ChunkIndex index, Metachunk* chunk); 196 197 // Total of the space in the free chunks list 198 size_t free_chunks_total_words(); 199 size_t free_chunks_total_bytes(); 200 201 // Number of chunks in the free chunks list 202 size_t free_chunks_count(); 203 204 // Remove from a list by size. Selects list based on size of chunk. 205 Metachunk* free_chunks_get(size_t chunk_word_size); 206 207 #define index_bounds_check(index) \ 208 assert(index == SpecializedIndex || \ 209 index == SmallIndex || \ 210 index == MediumIndex || \ 211 index == HumongousIndex, "Bad index: %d", (int) index) 212 213 size_t num_free_chunks(ChunkIndex index) const { 214 index_bounds_check(index); 215 216 if (index == HumongousIndex) { 217 return _humongous_dictionary.total_free_blocks(); 218 } 219 220 ssize_t count = _free_chunks[index].count(); 221 return count == -1 ? 0 : (size_t) count; 222 } 223 224 size_t size_free_chunks_in_bytes(ChunkIndex index) const { 225 index_bounds_check(index); 226 227 size_t word_size = 0; 228 if (index == HumongousIndex) { 229 word_size = _humongous_dictionary.total_size(); 230 } else { 231 const size_t size_per_chunk_in_words = _free_chunks[index].size(); 232 word_size = size_per_chunk_in_words * num_free_chunks(index); 233 } 234 235 return word_size * BytesPerWord; 236 } 237 238 MetaspaceChunkFreeListSummary chunk_free_list_summary() const { 239 return MetaspaceChunkFreeListSummary(num_free_chunks(SpecializedIndex), 240 num_free_chunks(SmallIndex), 241 num_free_chunks(MediumIndex), 242 num_free_chunks(HumongousIndex), 243 size_free_chunks_in_bytes(SpecializedIndex), 244 size_free_chunks_in_bytes(SmallIndex), 245 size_free_chunks_in_bytes(MediumIndex), 246 size_free_chunks_in_bytes(HumongousIndex)); 247 } 248 249 // Debug support 250 void verify(); 251 void slow_verify() { 252 if (metaspace_slow_verify) { 253 verify(); 254 } 255 } 256 void locked_verify(); 257 void slow_locked_verify() { 258 if (metaspace_slow_verify) { 259 locked_verify(); 260 } 261 } 262 void verify_free_chunks_total(); 263 264 void locked_print_free_chunks(outputStream* st); 265 void locked_print_sum_free_chunks(outputStream* st); 266 267 void print_on(outputStream* st) const; 268 }; 269 270 class SmallBlocks : public CHeapObj<mtClass> { 271 const static uint _small_block_max_size = sizeof(TreeChunk<Metablock, FreeList<Metablock> >)/HeapWordSize; 272 const static uint _small_block_min_size = sizeof(Metablock)/HeapWordSize; 273 274 private: 275 FreeList<Metablock> _small_lists[_small_block_max_size - _small_block_min_size]; 276 277 FreeList<Metablock>& list_at(size_t word_size) { 278 assert(word_size >= _small_block_min_size, "There are no metaspace objects less than %u words", _small_block_min_size); 279 return _small_lists[word_size - _small_block_min_size]; 280 } 281 282 public: 283 SmallBlocks() { 284 for (uint i = _small_block_min_size; i < _small_block_max_size; i++) { 285 uint k = i - _small_block_min_size; 286 _small_lists[k].set_size(i); 287 } 288 } 289 290 size_t total_size() const { 291 size_t result = 0; 292 for (uint i = _small_block_min_size; i < _small_block_max_size; i++) { 293 uint k = i - _small_block_min_size; 294 result = result + _small_lists[k].count() * _small_lists[k].size(); 295 } 296 return result; 297 } 298 299 static uint small_block_max_size() { return _small_block_max_size; } 300 static uint small_block_min_size() { return _small_block_min_size; } 301 302 MetaWord* get_block(size_t word_size) { 303 if (list_at(word_size).count() > 0) { 304 MetaWord* new_block = (MetaWord*) list_at(word_size).get_chunk_at_head(); 305 return new_block; 306 } else { 307 return NULL; 308 } 309 } 310 void return_block(Metablock* free_chunk, size_t word_size) { 311 list_at(word_size).return_chunk_at_head(free_chunk, false); 312 assert(list_at(word_size).count() > 0, "Should have a chunk"); 313 } 314 315 void print_on(outputStream* st) const { 316 st->print_cr("SmallBlocks:"); 317 for (uint i = _small_block_min_size; i < _small_block_max_size; i++) { 318 uint k = i - _small_block_min_size; 319 st->print_cr("small_lists size " SIZE_FORMAT " count " SIZE_FORMAT, _small_lists[k].size(), _small_lists[k].count()); 320 } 321 } 322 }; 323 324 // Used to manage the free list of Metablocks (a block corresponds 325 // to the allocation of a quantum of metadata). 326 class BlockFreelist : public CHeapObj<mtClass> { 327 BlockTreeDictionary* const _dictionary; 328 SmallBlocks* _small_blocks; 329 330 // Only allocate and split from freelist if the size of the allocation 331 // is at least 1/4th the size of the available block. 332 const static int WasteMultiplier = 4; 333 334 // Accessors 335 BlockTreeDictionary* dictionary() const { return _dictionary; } 336 SmallBlocks* small_blocks() { 337 if (_small_blocks == NULL) { 338 _small_blocks = new SmallBlocks(); 339 } 340 return _small_blocks; 341 } 342 343 public: 344 BlockFreelist(); 345 ~BlockFreelist(); 346 347 // Get and return a block to the free list 348 MetaWord* get_block(size_t word_size); 349 void return_block(MetaWord* p, size_t word_size); 350 351 size_t total_size() const { 352 size_t result = dictionary()->total_size(); 353 if (_small_blocks != NULL) { 354 result = result + _small_blocks->total_size(); 355 } 356 return result; 357 } 358 359 static size_t min_dictionary_size() { return TreeChunk<Metablock, FreeList<Metablock> >::min_size(); } 360 void print_on(outputStream* st) const; 361 }; 362 363 // A VirtualSpaceList node. 364 class VirtualSpaceNode : public CHeapObj<mtClass> { 365 friend class VirtualSpaceList; 366 367 // Link to next VirtualSpaceNode 368 VirtualSpaceNode* _next; 369 370 // total in the VirtualSpace 371 MemRegion _reserved; 372 ReservedSpace _rs; 373 VirtualSpace _virtual_space; 374 MetaWord* _top; 375 // count of chunks contained in this VirtualSpace 376 uintx _container_count; 377 378 // Convenience functions to access the _virtual_space 379 char* low() const { return virtual_space()->low(); } 380 char* high() const { return virtual_space()->high(); } 381 382 // The first Metachunk will be allocated at the bottom of the 383 // VirtualSpace 384 Metachunk* first_chunk() { return (Metachunk*) bottom(); } 385 386 // Committed but unused space in the virtual space 387 size_t free_words_in_vs() const; 388 public: 389 390 VirtualSpaceNode(size_t byte_size); 391 VirtualSpaceNode(ReservedSpace rs) : _top(NULL), _next(NULL), _rs(rs), _container_count(0) {} 392 ~VirtualSpaceNode(); 393 394 // Convenience functions for logical bottom and end 395 MetaWord* bottom() const { return (MetaWord*) _virtual_space.low(); } 396 MetaWord* end() const { return (MetaWord*) _virtual_space.high(); } 397 398 bool contains(const void* ptr) { return ptr >= low() && ptr < high(); } 399 400 size_t reserved_words() const { return _virtual_space.reserved_size() / BytesPerWord; } 401 size_t committed_words() const { return _virtual_space.actual_committed_size() / BytesPerWord; } 402 403 bool is_pre_committed() const { return _virtual_space.special(); } 404 405 // address of next available space in _virtual_space; 406 // Accessors 407 VirtualSpaceNode* next() { return _next; } 408 void set_next(VirtualSpaceNode* v) { _next = v; } 409 410 void set_reserved(MemRegion const v) { _reserved = v; } 411 void set_top(MetaWord* v) { _top = v; } 412 413 // Accessors 414 MemRegion* reserved() { return &_reserved; } 415 VirtualSpace* virtual_space() const { return (VirtualSpace*) &_virtual_space; } 416 417 // Returns true if "word_size" is available in the VirtualSpace 418 bool is_available(size_t word_size) { return word_size <= pointer_delta(end(), _top, sizeof(MetaWord)); } 419 420 MetaWord* top() const { return _top; } 421 void inc_top(size_t word_size) { _top += word_size; } 422 423 uintx container_count() { return _container_count; } 424 void inc_container_count(); 425 void dec_container_count(); 426 #ifdef ASSERT 427 uintx container_count_slow(); 428 void verify_container_count(); 429 #endif 430 431 // used and capacity in this single entry in the list 432 size_t used_words_in_vs() const; 433 size_t capacity_words_in_vs() const; 434 435 bool initialize(); 436 437 // get space from the virtual space 438 Metachunk* take_from_committed(size_t chunk_word_size); 439 440 // Allocate a chunk from the virtual space and return it. 441 Metachunk* get_chunk_vs(size_t chunk_word_size); 442 443 // Expands/shrinks the committed space in a virtual space. Delegates 444 // to Virtualspace 445 bool expand_by(size_t min_words, size_t preferred_words); 446 447 // In preparation for deleting this node, remove all the chunks 448 // in the node from any freelist. 449 void purge(ChunkManager* chunk_manager); 450 451 // If an allocation doesn't fit in the current node a new node is created. 452 // Allocate chunks out of the remaining committed space in this node 453 // to avoid wasting that memory. 454 // This always adds up because all the chunk sizes are multiples of 455 // the smallest chunk size. 456 void retire(ChunkManager* chunk_manager); 457 458 #ifdef ASSERT 459 // Debug support 460 void mangle(); 461 #endif 462 463 void print_on(outputStream* st) const; 464 }; 465 466 #define assert_is_aligned(value, alignment) \ 467 assert(is_aligned((value), (alignment)), \ 468 SIZE_FORMAT_HEX " is not aligned to " \ 469 SIZE_FORMAT, (size_t)(uintptr_t)value, (alignment)) 470 471 // Decide if large pages should be committed when the memory is reserved. 472 static bool should_commit_large_pages_when_reserving(size_t bytes) { 473 if (UseLargePages && UseLargePagesInMetaspace && !os::can_commit_large_page_memory()) { 474 size_t words = bytes / BytesPerWord; 475 bool is_class = false; // We never reserve large pages for the class space. 476 if (MetaspaceGC::can_expand(words, is_class) && 477 MetaspaceGC::allowed_expansion() >= words) { 478 return true; 479 } 480 } 481 482 return false; 483 } 484 485 // byte_size is the size of the associated virtualspace. 486 VirtualSpaceNode::VirtualSpaceNode(size_t bytes) : _top(NULL), _next(NULL), _rs(), _container_count(0) { 487 assert_is_aligned(bytes, Metaspace::reserve_alignment()); 488 489 #if INCLUDE_CDS 490 // This allocates memory with mmap. For DumpSharedspaces, try to reserve 491 // configurable address, generally at the top of the Java heap so other 492 // memory addresses don't conflict. 493 if (DumpSharedSpaces) { 494 bool large_pages = false; // No large pages when dumping the CDS archive. 495 char* shared_base = align_up((char*)SharedBaseAddress, Metaspace::reserve_alignment()); 496 497 _rs = ReservedSpace(bytes, Metaspace::reserve_alignment(), large_pages, shared_base); 498 if (_rs.is_reserved()) { 499 assert(shared_base == 0 || _rs.base() == shared_base, "should match"); 500 } else { 501 // Get a mmap region anywhere if the SharedBaseAddress fails. 502 _rs = ReservedSpace(bytes, Metaspace::reserve_alignment(), large_pages); 503 } 504 if (!_rs.is_reserved()) { 505 vm_exit_during_initialization("Unable to allocate memory for shared space", 506 err_msg(SIZE_FORMAT " bytes.", bytes)); 507 } 508 MetaspaceShared::initialize_shared_rs(&_rs); 509 } else 510 #endif 511 { 512 bool large_pages = should_commit_large_pages_when_reserving(bytes); 513 514 _rs = ReservedSpace(bytes, Metaspace::reserve_alignment(), large_pages); 515 } 516 517 if (_rs.is_reserved()) { 518 assert(_rs.base() != NULL, "Catch if we get a NULL address"); 519 assert(_rs.size() != 0, "Catch if we get a 0 size"); 520 assert_is_aligned(_rs.base(), Metaspace::reserve_alignment()); 521 assert_is_aligned(_rs.size(), Metaspace::reserve_alignment()); 522 523 MemTracker::record_virtual_memory_type((address)_rs.base(), mtClass); 524 } 525 } 526 527 void VirtualSpaceNode::purge(ChunkManager* chunk_manager) { 528 Metachunk* chunk = first_chunk(); 529 Metachunk* invalid_chunk = (Metachunk*) top(); 530 while (chunk < invalid_chunk ) { 531 assert(chunk->is_tagged_free(), "Should be tagged free"); 532 MetaWord* next = ((MetaWord*)chunk) + chunk->word_size(); 533 chunk_manager->remove_chunk(chunk); 534 assert(chunk->next() == NULL && 535 chunk->prev() == NULL, 536 "Was not removed from its list"); 537 chunk = (Metachunk*) next; 538 } 539 } 540 541 #ifdef ASSERT 542 uintx VirtualSpaceNode::container_count_slow() { 543 uintx count = 0; 544 Metachunk* chunk = first_chunk(); 545 Metachunk* invalid_chunk = (Metachunk*) top(); 546 while (chunk < invalid_chunk ) { 547 MetaWord* next = ((MetaWord*)chunk) + chunk->word_size(); 548 // Don't count the chunks on the free lists. Those are 549 // still part of the VirtualSpaceNode but not currently 550 // counted. 551 if (!chunk->is_tagged_free()) { 552 count++; 553 } 554 chunk = (Metachunk*) next; 555 } 556 return count; 557 } 558 #endif 559 560 // List of VirtualSpaces for metadata allocation. 561 class VirtualSpaceList : public CHeapObj<mtClass> { 562 friend class VirtualSpaceNode; 563 564 enum VirtualSpaceSizes { 565 VirtualSpaceSize = 256 * K 566 }; 567 568 // Head of the list 569 VirtualSpaceNode* _virtual_space_list; 570 // virtual space currently being used for allocations 571 VirtualSpaceNode* _current_virtual_space; 572 573 // Is this VirtualSpaceList used for the compressed class space 574 bool _is_class; 575 576 // Sum of reserved and committed memory in the virtual spaces 577 size_t _reserved_words; 578 size_t _committed_words; 579 580 // Number of virtual spaces 581 size_t _virtual_space_count; 582 583 ~VirtualSpaceList(); 584 585 VirtualSpaceNode* virtual_space_list() const { return _virtual_space_list; } 586 587 void set_virtual_space_list(VirtualSpaceNode* v) { 588 _virtual_space_list = v; 589 } 590 void set_current_virtual_space(VirtualSpaceNode* v) { 591 _current_virtual_space = v; 592 } 593 594 void link_vs(VirtualSpaceNode* new_entry); 595 596 // Get another virtual space and add it to the list. This 597 // is typically prompted by a failed attempt to allocate a chunk 598 // and is typically followed by the allocation of a chunk. 599 bool create_new_virtual_space(size_t vs_word_size); 600 601 // Chunk up the unused committed space in the current 602 // virtual space and add the chunks to the free list. 603 void retire_current_virtual_space(); 604 605 public: 606 VirtualSpaceList(size_t word_size); 607 VirtualSpaceList(ReservedSpace rs); 608 609 size_t free_bytes(); 610 611 Metachunk* get_new_chunk(size_t chunk_word_size, 612 size_t suggested_commit_granularity); 613 614 bool expand_node_by(VirtualSpaceNode* node, 615 size_t min_words, 616 size_t preferred_words); 617 618 bool expand_by(size_t min_words, 619 size_t preferred_words); 620 621 VirtualSpaceNode* current_virtual_space() { 622 return _current_virtual_space; 623 } 624 625 bool is_class() const { return _is_class; } 626 627 bool initialization_succeeded() { return _virtual_space_list != NULL; } 628 629 size_t reserved_words() { return _reserved_words; } 630 size_t reserved_bytes() { return reserved_words() * BytesPerWord; } 631 size_t committed_words() { return _committed_words; } 632 size_t committed_bytes() { return committed_words() * BytesPerWord; } 633 634 void inc_reserved_words(size_t v); 635 void dec_reserved_words(size_t v); 636 void inc_committed_words(size_t v); 637 void dec_committed_words(size_t v); 638 void inc_virtual_space_count(); 639 void dec_virtual_space_count(); 640 641 bool contains(const void* ptr); 642 643 // Unlink empty VirtualSpaceNodes and free it. 644 void purge(ChunkManager* chunk_manager); 645 646 void print_on(outputStream* st) const; 647 648 class VirtualSpaceListIterator : public StackObj { 649 VirtualSpaceNode* _virtual_spaces; 650 public: 651 VirtualSpaceListIterator(VirtualSpaceNode* virtual_spaces) : 652 _virtual_spaces(virtual_spaces) {} 653 654 bool repeat() { 655 return _virtual_spaces != NULL; 656 } 657 658 VirtualSpaceNode* get_next() { 659 VirtualSpaceNode* result = _virtual_spaces; 660 if (_virtual_spaces != NULL) { 661 _virtual_spaces = _virtual_spaces->next(); 662 } 663 return result; 664 } 665 }; 666 }; 667 668 class Metadebug : AllStatic { 669 // Debugging support for Metaspaces 670 static int _allocation_fail_alot_count; 671 672 public: 673 674 static void init_allocation_fail_alot_count(); 675 #ifdef ASSERT 676 static bool test_metadata_failure(); 677 #endif 678 }; 679 680 int Metadebug::_allocation_fail_alot_count = 0; 681 682 // SpaceManager - used by Metaspace to handle allocations 683 class SpaceManager : public CHeapObj<mtClass> { 684 friend class Metaspace; 685 friend class Metadebug; 686 687 private: 688 689 // protects allocations 690 Mutex* const _lock; 691 692 // Type of metadata allocated. 693 Metaspace::MetadataType _mdtype; 694 695 // List of chunks in use by this SpaceManager. Allocations 696 // are done from the current chunk. The list is used for deallocating 697 // chunks when the SpaceManager is freed. 698 Metachunk* _chunks_in_use[NumberOfInUseLists]; 699 Metachunk* _current_chunk; 700 701 // Maximum number of small chunks to allocate to a SpaceManager 702 static uint const _small_chunk_limit; 703 704 // Sum of all space in allocated chunks 705 size_t _allocated_blocks_words; 706 707 // Sum of all allocated chunks 708 size_t _allocated_chunks_words; 709 size_t _allocated_chunks_count; 710 711 // Free lists of blocks are per SpaceManager since they 712 // are assumed to be in chunks in use by the SpaceManager 713 // and all chunks in use by a SpaceManager are freed when 714 // the class loader using the SpaceManager is collected. 715 BlockFreelist* _block_freelists; 716 717 // protects virtualspace and chunk expansions 718 static const char* _expand_lock_name; 719 static const int _expand_lock_rank; 720 static Mutex* const _expand_lock; 721 722 private: 723 // Accessors 724 Metachunk* chunks_in_use(ChunkIndex index) const { return _chunks_in_use[index]; } 725 void set_chunks_in_use(ChunkIndex index, Metachunk* v) { 726 _chunks_in_use[index] = v; 727 } 728 729 BlockFreelist* block_freelists() const { return _block_freelists; } 730 731 Metaspace::MetadataType mdtype() { return _mdtype; } 732 733 VirtualSpaceList* vs_list() const { return Metaspace::get_space_list(_mdtype); } 734 ChunkManager* chunk_manager() const { return Metaspace::get_chunk_manager(_mdtype); } 735 736 Metachunk* current_chunk() const { return _current_chunk; } 737 void set_current_chunk(Metachunk* v) { 738 _current_chunk = v; 739 } 740 741 Metachunk* find_current_chunk(size_t word_size); 742 743 // Add chunk to the list of chunks in use 744 void add_chunk(Metachunk* v, bool make_current); 745 void retire_current_chunk(); 746 747 Mutex* lock() const { return _lock; } 748 749 protected: 750 void initialize(); 751 752 public: 753 SpaceManager(Metaspace::MetadataType mdtype, 754 Mutex* lock); 755 ~SpaceManager(); 756 757 enum ChunkMultiples { 758 MediumChunkMultiple = 4 759 }; 760 761 static size_t specialized_chunk_size(bool is_class) { return is_class ? ClassSpecializedChunk : SpecializedChunk; } 762 static size_t small_chunk_size(bool is_class) { return is_class ? ClassSmallChunk : SmallChunk; } 763 static size_t medium_chunk_size(bool is_class) { return is_class ? ClassMediumChunk : MediumChunk; } 764 765 static size_t smallest_chunk_size(bool is_class) { return specialized_chunk_size(is_class); } 766 767 // Accessors 768 bool is_class() const { return _mdtype == Metaspace::ClassType; } 769 770 size_t specialized_chunk_size() const { return specialized_chunk_size(is_class()); } 771 size_t small_chunk_size() const { return small_chunk_size(is_class()); } 772 size_t medium_chunk_size() const { return medium_chunk_size(is_class()); } 773 774 size_t smallest_chunk_size() const { return smallest_chunk_size(is_class()); } 775 776 size_t medium_chunk_bunch() const { return medium_chunk_size() * MediumChunkMultiple; } 777 778 size_t allocated_blocks_words() const { return _allocated_blocks_words; } 779 size_t allocated_blocks_bytes() const { return _allocated_blocks_words * BytesPerWord; } 780 size_t allocated_chunks_words() const { return _allocated_chunks_words; } 781 size_t allocated_chunks_bytes() const { return _allocated_chunks_words * BytesPerWord; } 782 size_t allocated_chunks_count() const { return _allocated_chunks_count; } 783 784 bool is_humongous(size_t word_size) { return word_size > medium_chunk_size(); } 785 786 static Mutex* expand_lock() { return _expand_lock; } 787 788 // Increment the per Metaspace and global running sums for Metachunks 789 // by the given size. This is used when a Metachunk to added to 790 // the in-use list. 791 void inc_size_metrics(size_t words); 792 // Increment the per Metaspace and global running sums Metablocks by the given 793 // size. This is used when a Metablock is allocated. 794 void inc_used_metrics(size_t words); 795 // Delete the portion of the running sums for this SpaceManager. That is, 796 // the globals running sums for the Metachunks and Metablocks are 797 // decremented for all the Metachunks in-use by this SpaceManager. 798 void dec_total_from_size_metrics(); 799 800 // Adjust the initial chunk size to match one of the fixed chunk list sizes, 801 // or return the unadjusted size if the requested size is humongous. 802 static size_t adjust_initial_chunk_size(size_t requested, bool is_class_space); 803 size_t adjust_initial_chunk_size(size_t requested) const; 804 805 // Get the initial chunks size for this metaspace type. 806 size_t get_initial_chunk_size(Metaspace::MetaspaceType type) const; 807 808 size_t sum_capacity_in_chunks_in_use() const; 809 size_t sum_used_in_chunks_in_use() const; 810 size_t sum_free_in_chunks_in_use() const; 811 size_t sum_waste_in_chunks_in_use() const; 812 size_t sum_waste_in_chunks_in_use(ChunkIndex index ) const; 813 814 size_t sum_count_in_chunks_in_use(); 815 size_t sum_count_in_chunks_in_use(ChunkIndex i); 816 817 Metachunk* get_new_chunk(size_t chunk_word_size); 818 819 // Block allocation and deallocation. 820 // Allocates a block from the current chunk 821 MetaWord* allocate(size_t word_size); 822 // Allocates a block from a small chunk 823 MetaWord* get_small_chunk_and_allocate(size_t word_size); 824 825 // Helper for allocations 826 MetaWord* allocate_work(size_t word_size); 827 828 // Returns a block to the per manager freelist 829 void deallocate(MetaWord* p, size_t word_size); 830 831 // Based on the allocation size and a minimum chunk size, 832 // returned chunk size (for expanding space for chunk allocation). 833 size_t calc_chunk_size(size_t allocation_word_size); 834 835 // Called when an allocation from the current chunk fails. 836 // Gets a new chunk (may require getting a new virtual space), 837 // and allocates from that chunk. 838 MetaWord* grow_and_allocate(size_t word_size); 839 840 // Notify memory usage to MemoryService. 841 void track_metaspace_memory_usage(); 842 843 // debugging support. 844 845 void dump(outputStream* const out) const; 846 void print_on(outputStream* st) const; 847 void locked_print_chunks_in_use_on(outputStream* st) const; 848 849 void verify(); 850 void verify_chunk_size(Metachunk* chunk); 851 #ifdef ASSERT 852 void verify_allocated_blocks_words(); 853 #endif 854 855 // This adjusts the size given to be greater than the minimum allocation size in 856 // words for data in metaspace. Esentially the minimum size is currently 3 words. 857 size_t get_allocation_word_size(size_t word_size) { 858 size_t byte_size = word_size * BytesPerWord; 859 860 size_t raw_bytes_size = MAX2(byte_size, sizeof(Metablock)); 861 raw_bytes_size = align_up(raw_bytes_size, Metachunk::object_alignment()); 862 863 size_t raw_word_size = raw_bytes_size / BytesPerWord; 864 assert(raw_word_size * BytesPerWord == raw_bytes_size, "Size problem"); 865 866 return raw_word_size; 867 } 868 }; 869 870 uint const SpaceManager::_small_chunk_limit = 4; 871 872 const char* SpaceManager::_expand_lock_name = 873 "SpaceManager chunk allocation lock"; 874 const int SpaceManager::_expand_lock_rank = Monitor::leaf - 1; 875 Mutex* const SpaceManager::_expand_lock = 876 new Mutex(SpaceManager::_expand_lock_rank, 877 SpaceManager::_expand_lock_name, 878 Mutex::_allow_vm_block_flag, 879 Monitor::_safepoint_check_never); 880 881 void VirtualSpaceNode::inc_container_count() { 882 assert_lock_strong(SpaceManager::expand_lock()); 883 _container_count++; 884 } 885 886 void VirtualSpaceNode::dec_container_count() { 887 assert_lock_strong(SpaceManager::expand_lock()); 888 _container_count--; 889 } 890 891 #ifdef ASSERT 892 void VirtualSpaceNode::verify_container_count() { 893 assert(_container_count == container_count_slow(), 894 "Inconsistency in container_count _container_count " UINTX_FORMAT 895 " container_count_slow() " UINTX_FORMAT, _container_count, container_count_slow()); 896 } 897 #endif 898 899 // BlockFreelist methods 900 901 BlockFreelist::BlockFreelist() : _dictionary(new BlockTreeDictionary()), _small_blocks(NULL) {} 902 903 BlockFreelist::~BlockFreelist() { 904 delete _dictionary; 905 if (_small_blocks != NULL) { 906 delete _small_blocks; 907 } 908 } 909 910 void BlockFreelist::return_block(MetaWord* p, size_t word_size) { 911 assert(word_size >= SmallBlocks::small_block_min_size(), "never return dark matter"); 912 913 Metablock* free_chunk = ::new (p) Metablock(word_size); 914 if (word_size < SmallBlocks::small_block_max_size()) { 915 small_blocks()->return_block(free_chunk, word_size); 916 } else { 917 dictionary()->return_chunk(free_chunk); 918 } 919 log_trace(gc, metaspace, freelist, blocks)("returning block at " INTPTR_FORMAT " size = " 920 SIZE_FORMAT, p2i(free_chunk), word_size); 921 } 922 923 MetaWord* BlockFreelist::get_block(size_t word_size) { 924 assert(word_size >= SmallBlocks::small_block_min_size(), "never get dark matter"); 925 926 // Try small_blocks first. 927 if (word_size < SmallBlocks::small_block_max_size()) { 928 // Don't create small_blocks() until needed. small_blocks() allocates the small block list for 929 // this space manager. 930 MetaWord* new_block = (MetaWord*) small_blocks()->get_block(word_size); 931 if (new_block != NULL) { 932 log_trace(gc, metaspace, freelist, blocks)("getting block at " INTPTR_FORMAT " size = " SIZE_FORMAT, 933 p2i(new_block), word_size); 934 return new_block; 935 } 936 } 937 938 if (word_size < BlockFreelist::min_dictionary_size()) { 939 // If allocation in small blocks fails, this is Dark Matter. Too small for dictionary. 940 return NULL; 941 } 942 943 Metablock* free_block = dictionary()->get_chunk(word_size); 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 } 965 966 void 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 974 975 VirtualSpaceNode::~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 } 982 983 size_t VirtualSpaceNode::used_words_in_vs() const { 984 return pointer_delta(top(), bottom(), sizeof(MetaWord)); 985 } 986 987 // Space committed in the VirtualSpace 988 size_t VirtualSpaceNode::capacity_words_in_vs() const { 989 return pointer_delta(end(), bottom(), sizeof(MetaWord)); 990 } 991 992 size_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. 999 Metachunk* 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) 1029 bool 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 1047 Metachunk* 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 1056 bool 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 1095 void 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 1109 void 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 1118 VirtualSpaceList::~VirtualSpaceList() { 1119 VirtualSpaceListIterator iter(virtual_space_list()); 1120 while (iter.repeat()) { 1121 VirtualSpaceNode* vsl = iter.get_next(); 1122 delete vsl; 1123 } 1124 } 1125 1126 void VirtualSpaceList::inc_reserved_words(size_t v) { 1127 assert_lock_strong(SpaceManager::expand_lock()); 1128 _reserved_words = _reserved_words + v; 1129 } 1130 void 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 1141 void 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 } 1147 void 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 1154 void VirtualSpaceList::inc_virtual_space_count() { 1155 assert_lock_strong(SpaceManager::expand_lock()); 1156 _virtual_space_count++; 1157 } 1158 void VirtualSpaceList::dec_virtual_space_count() { 1159 assert_lock_strong(SpaceManager::expand_lock()); 1160 _virtual_space_count--; 1161 } 1162 1163 void 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. 1179 void 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. 1229 bool 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 1242 void 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 1253 void 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 1270 VirtualSpaceList::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 1282 VirtualSpaceList::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 1298 size_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. 1303 bool 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 1337 void 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 1358 bool 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 1374 bool 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 1420 Metachunk* 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 1448 void 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. 1482 size_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 1505 size_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 1511 bool 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 1538 size_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 1544 void 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 1550 void 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 1555 bool 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 1573 size_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 1588 void 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 1707 void 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 1715 bool 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 1732 size_t ChunkManager::free_chunks_total_words() { 1733 return _free_chunks_total; 1734 } 1735 1736 size_t ChunkManager::free_chunks_total_bytes() { 1737 return free_chunks_total_words() * BytesPerWord; 1738 } 1739 1740 // Update internal accounting after a chunk was added 1741 void 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 1748 void 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 1759 size_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 1772 ChunkIndex 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 1788 size_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 1794 void 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 1802 void 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 1808 void 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 1816 void 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 1824 void ChunkManager::verify() { 1825 MutexLockerEx cl(SpaceManager::expand_lock(), 1826 Mutex::_no_safepoint_check_flag); 1827 locked_verify(); 1828 } 1829 1830 void ChunkManager::locked_verify() { 1831 locked_verify_free_chunks_count(); 1832 locked_verify_free_chunks_total(); 1833 } 1834 1835 void 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 1841 void 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 1847 ChunkList* 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. 1856 size_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 1872 size_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 1886 ChunkList* 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 1892 Metachunk* 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(word_size); 1915 1916 if (chunk == NULL) { 1917 return NULL; 1918 } 1919 1920 log_debug(gc, metaspace, alloc)("Free list allocate humongous chunk size " SIZE_FORMAT " for requested size " SIZE_FORMAT " waste " SIZE_FORMAT, 1921 chunk->word_size(), word_size, chunk->word_size() - word_size); 1922 } 1923 1924 // Chunk has been removed from the chunk manager; update counters. 1925 account_for_removed_chunk(chunk); 1926 1927 // Remove it from the links to this freelist 1928 chunk->set_next(NULL); 1929 chunk->set_prev(NULL); 1930 #ifdef ASSERT 1931 // Chunk is no longer on any freelist. Setting to false make container_count_slow() 1932 // work. 1933 chunk->set_is_tagged_free(false); 1934 #endif 1935 chunk->container()->inc_container_count(); 1936 1937 slow_locked_verify(); 1938 return chunk; 1939 } 1940 1941 Metachunk* ChunkManager::chunk_freelist_allocate(size_t word_size) { 1942 assert_lock_strong(SpaceManager::expand_lock()); 1943 slow_locked_verify(); 1944 1945 // Take from the beginning of the list 1946 Metachunk* chunk = free_chunks_get(word_size); 1947 if (chunk == NULL) { 1948 return NULL; 1949 } 1950 1951 assert((word_size <= chunk->word_size()) || 1952 (list_index(chunk->word_size()) == HumongousIndex), 1953 "Non-humongous variable sized chunk"); 1954 Log(gc, metaspace, freelist) log; 1955 if (log.is_debug()) { 1956 size_t list_count; 1957 if (list_index(word_size) < HumongousIndex) { 1958 ChunkList* list = find_free_chunks_list(word_size); 1959 list_count = list->count(); 1960 } else { 1961 list_count = humongous_dictionary()->total_count(); 1962 } 1963 log.debug("ChunkManager::chunk_freelist_allocate: " PTR_FORMAT " chunk " PTR_FORMAT " size " SIZE_FORMAT " count " SIZE_FORMAT " ", 1964 p2i(this), p2i(chunk), chunk->word_size(), list_count); 1965 ResourceMark rm; 1966 locked_print_free_chunks(log.debug_stream()); 1967 } 1968 1969 return chunk; 1970 } 1971 1972 void ChunkManager::return_single_chunk(ChunkIndex index, Metachunk* chunk) { 1973 assert_lock_strong(SpaceManager::expand_lock()); 1974 assert(chunk != NULL, "Expected chunk."); 1975 assert(chunk->container() != NULL, "Container should have been set."); 1976 assert(chunk->is_tagged_free() == false, "Chunk should be in use."); 1977 index_bounds_check(index); 1978 1979 // Note: mangle *before* returning the chunk to the freelist or dictionary. It does not 1980 // matter for the freelist (non-humongous chunks), but the humongous chunk dictionary 1981 // keeps tree node pointers in the chunk payload area which mangle will overwrite. 1982 NOT_PRODUCT(chunk->mangle(badMetaWordVal);) 1983 1984 if (index != HumongousIndex) { 1985 // Return non-humongous chunk to freelist. 1986 ChunkList* list = free_chunks(index); 1987 assert(list->size() == chunk->word_size(), "Wrong chunk type."); 1988 list->return_chunk_at_head(chunk); 1989 log_trace(gc, metaspace, freelist)("returned one %s chunk at " PTR_FORMAT " to freelist.", 1990 chunk_size_name(index), p2i(chunk)); 1991 } else { 1992 // Return humongous chunk to dictionary. 1993 assert(chunk->word_size() > free_chunks(MediumIndex)->size(), "Wrong chunk type."); 1994 assert(chunk->word_size() % free_chunks(SpecializedIndex)->size() == 0, 1995 "Humongous chunk has wrong alignment."); 1996 _humongous_dictionary.return_chunk(chunk); 1997 log_trace(gc, metaspace, freelist)("returned one %s chunk at " PTR_FORMAT " (word size " SIZE_FORMAT ") to freelist.", 1998 chunk_size_name(index), p2i(chunk), chunk->word_size()); 1999 } 2000 chunk->container()->dec_container_count(); 2001 DEBUG_ONLY(chunk->set_is_tagged_free(true);) 2002 2003 // Chunk has been added; update counters. 2004 account_for_added_chunk(chunk); 2005 2006 } 2007 2008 void ChunkManager::return_chunk_list(ChunkIndex index, Metachunk* chunks) { 2009 index_bounds_check(index); 2010 if (chunks == NULL) { 2011 return; 2012 } 2013 LogTarget(Trace, gc, metaspace, freelist) log; 2014 if (log.is_enabled()) { // tracing 2015 log.print("returning list of %s chunks...", chunk_size_name(index)); 2016 } 2017 unsigned num_chunks_returned = 0; 2018 size_t size_chunks_returned = 0; 2019 Metachunk* cur = chunks; 2020 while (cur != NULL) { 2021 // Capture the next link before it is changed 2022 // by the call to return_chunk_at_head(); 2023 Metachunk* next = cur->next(); 2024 if (log.is_enabled()) { // tracing 2025 num_chunks_returned ++; 2026 size_chunks_returned += cur->word_size(); 2027 } 2028 return_single_chunk(index, cur); 2029 cur = next; 2030 } 2031 if (log.is_enabled()) { // tracing 2032 log.print("returned %u %s chunks to freelist, total word size " SIZE_FORMAT ".", 2033 num_chunks_returned, chunk_size_name(index), size_chunks_returned); 2034 if (index != HumongousIndex) { 2035 log.print("updated freelist count: " SIZE_FORMAT ".", free_chunks(index)->size()); 2036 } else { 2037 log.print("updated dictionary count " SIZE_FORMAT ".", _humongous_dictionary.total_count()); 2038 } 2039 } 2040 } 2041 2042 void ChunkManager::print_on(outputStream* out) const { 2043 const_cast<ChunkManager *>(this)->humongous_dictionary()->report_statistics(out); 2044 } 2045 2046 // SpaceManager methods 2047 2048 size_t SpaceManager::adjust_initial_chunk_size(size_t requested, bool is_class_space) { 2049 size_t chunk_sizes[] = { 2050 specialized_chunk_size(is_class_space), 2051 small_chunk_size(is_class_space), 2052 medium_chunk_size(is_class_space) 2053 }; 2054 2055 // Adjust up to one of the fixed chunk sizes ... 2056 for (size_t i = 0; i < ARRAY_SIZE(chunk_sizes); i++) { 2057 if (requested <= chunk_sizes[i]) { 2058 return chunk_sizes[i]; 2059 } 2060 } 2061 2062 // ... or return the size as a humongous chunk. 2063 return requested; 2064 } 2065 2066 size_t SpaceManager::adjust_initial_chunk_size(size_t requested) const { 2067 return adjust_initial_chunk_size(requested, is_class()); 2068 } 2069 2070 size_t SpaceManager::get_initial_chunk_size(Metaspace::MetaspaceType type) const { 2071 size_t requested; 2072 2073 if (is_class()) { 2074 switch (type) { 2075 case Metaspace::BootMetaspaceType: requested = Metaspace::first_class_chunk_word_size(); break; 2076 case Metaspace::ROMetaspaceType: requested = ClassSpecializedChunk; break; 2077 case Metaspace::ReadWriteMetaspaceType: requested = ClassSpecializedChunk; break; 2078 case Metaspace::AnonymousMetaspaceType: requested = ClassSpecializedChunk; break; 2079 case Metaspace::ReflectionMetaspaceType: requested = ClassSpecializedChunk; break; 2080 default: requested = ClassSmallChunk; break; 2081 } 2082 } else { 2083 switch (type) { 2084 case Metaspace::BootMetaspaceType: requested = Metaspace::first_chunk_word_size(); break; 2085 case Metaspace::ROMetaspaceType: requested = SharedReadOnlySize / wordSize; break; 2086 case Metaspace::ReadWriteMetaspaceType: requested = SharedReadWriteSize / wordSize; break; 2087 case Metaspace::AnonymousMetaspaceType: requested = SpecializedChunk; break; 2088 case Metaspace::ReflectionMetaspaceType: requested = SpecializedChunk; break; 2089 default: requested = SmallChunk; break; 2090 } 2091 } 2092 2093 // Adjust to one of the fixed chunk sizes (unless humongous) 2094 const size_t adjusted = adjust_initial_chunk_size(requested); 2095 2096 assert(adjusted != 0, "Incorrect initial chunk size. Requested: " 2097 SIZE_FORMAT " adjusted: " SIZE_FORMAT, requested, adjusted); 2098 2099 return adjusted; 2100 } 2101 2102 size_t SpaceManager::sum_free_in_chunks_in_use() const { 2103 MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag); 2104 size_t free = 0; 2105 for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) { 2106 Metachunk* chunk = chunks_in_use(i); 2107 while (chunk != NULL) { 2108 free += chunk->free_word_size(); 2109 chunk = chunk->next(); 2110 } 2111 } 2112 return free; 2113 } 2114 2115 size_t SpaceManager::sum_waste_in_chunks_in_use() const { 2116 MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag); 2117 size_t result = 0; 2118 for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) { 2119 result += sum_waste_in_chunks_in_use(i); 2120 } 2121 2122 return result; 2123 } 2124 2125 size_t SpaceManager::sum_waste_in_chunks_in_use(ChunkIndex index) const { 2126 size_t result = 0; 2127 Metachunk* chunk = chunks_in_use(index); 2128 // Count the free space in all the chunk but not the 2129 // current chunk from which allocations are still being done. 2130 while (chunk != NULL) { 2131 if (chunk != current_chunk()) { 2132 result += chunk->free_word_size(); 2133 } 2134 chunk = chunk->next(); 2135 } 2136 return result; 2137 } 2138 2139 size_t SpaceManager::sum_capacity_in_chunks_in_use() const { 2140 // For CMS use "allocated_chunks_words()" which does not need the 2141 // Metaspace lock. For the other collectors sum over the 2142 // lists. Use both methods as a check that "allocated_chunks_words()" 2143 // is correct. That is, sum_capacity_in_chunks() is too expensive 2144 // to use in the product and allocated_chunks_words() should be used 2145 // but allow for checking that allocated_chunks_words() returns the same 2146 // value as sum_capacity_in_chunks_in_use() which is the definitive 2147 // answer. 2148 if (UseConcMarkSweepGC) { 2149 return allocated_chunks_words(); 2150 } else { 2151 MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag); 2152 size_t sum = 0; 2153 for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) { 2154 Metachunk* chunk = chunks_in_use(i); 2155 while (chunk != NULL) { 2156 sum += chunk->word_size(); 2157 chunk = chunk->next(); 2158 } 2159 } 2160 return sum; 2161 } 2162 } 2163 2164 size_t SpaceManager::sum_count_in_chunks_in_use() { 2165 size_t count = 0; 2166 for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) { 2167 count = count + sum_count_in_chunks_in_use(i); 2168 } 2169 2170 return count; 2171 } 2172 2173 size_t SpaceManager::sum_count_in_chunks_in_use(ChunkIndex i) { 2174 size_t count = 0; 2175 Metachunk* chunk = chunks_in_use(i); 2176 while (chunk != NULL) { 2177 count++; 2178 chunk = chunk->next(); 2179 } 2180 return count; 2181 } 2182 2183 2184 size_t SpaceManager::sum_used_in_chunks_in_use() const { 2185 MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag); 2186 size_t used = 0; 2187 for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) { 2188 Metachunk* chunk = chunks_in_use(i); 2189 while (chunk != NULL) { 2190 used += chunk->used_word_size(); 2191 chunk = chunk->next(); 2192 } 2193 } 2194 return used; 2195 } 2196 2197 void SpaceManager::locked_print_chunks_in_use_on(outputStream* st) const { 2198 2199 for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) { 2200 Metachunk* chunk = chunks_in_use(i); 2201 st->print("SpaceManager: %s " PTR_FORMAT, 2202 chunk_size_name(i), p2i(chunk)); 2203 if (chunk != NULL) { 2204 st->print_cr(" free " SIZE_FORMAT, 2205 chunk->free_word_size()); 2206 } else { 2207 st->cr(); 2208 } 2209 } 2210 2211 chunk_manager()->locked_print_free_chunks(st); 2212 chunk_manager()->locked_print_sum_free_chunks(st); 2213 } 2214 2215 size_t SpaceManager::calc_chunk_size(size_t word_size) { 2216 2217 // Decide between a small chunk and a medium chunk. Up to 2218 // _small_chunk_limit small chunks can be allocated. 2219 // After that a medium chunk is preferred. 2220 size_t chunk_word_size; 2221 if (chunks_in_use(MediumIndex) == NULL && 2222 sum_count_in_chunks_in_use(SmallIndex) < _small_chunk_limit) { 2223 chunk_word_size = (size_t) small_chunk_size(); 2224 if (word_size + Metachunk::overhead() > small_chunk_size()) { 2225 chunk_word_size = medium_chunk_size(); 2226 } 2227 } else { 2228 chunk_word_size = medium_chunk_size(); 2229 } 2230 2231 // Might still need a humongous chunk. Enforce 2232 // humongous allocations sizes to be aligned up to 2233 // the smallest chunk size. 2234 size_t if_humongous_sized_chunk = 2235 align_up(word_size + Metachunk::overhead(), 2236 smallest_chunk_size()); 2237 chunk_word_size = 2238 MAX2((size_t) chunk_word_size, if_humongous_sized_chunk); 2239 2240 assert(!SpaceManager::is_humongous(word_size) || 2241 chunk_word_size == if_humongous_sized_chunk, 2242 "Size calculation is wrong, word_size " SIZE_FORMAT 2243 " chunk_word_size " SIZE_FORMAT, 2244 word_size, chunk_word_size); 2245 Log(gc, metaspace, alloc) log; 2246 if (log.is_debug() && SpaceManager::is_humongous(word_size)) { 2247 log.debug("Metadata humongous allocation:"); 2248 log.debug(" word_size " PTR_FORMAT, word_size); 2249 log.debug(" chunk_word_size " PTR_FORMAT, chunk_word_size); 2250 log.debug(" chunk overhead " PTR_FORMAT, Metachunk::overhead()); 2251 } 2252 return chunk_word_size; 2253 } 2254 2255 void SpaceManager::track_metaspace_memory_usage() { 2256 if (is_init_completed()) { 2257 if (is_class()) { 2258 MemoryService::track_compressed_class_memory_usage(); 2259 } 2260 MemoryService::track_metaspace_memory_usage(); 2261 } 2262 } 2263 2264 MetaWord* SpaceManager::grow_and_allocate(size_t word_size) { 2265 assert(vs_list()->current_virtual_space() != NULL, 2266 "Should have been set"); 2267 assert(current_chunk() == NULL || 2268 current_chunk()->allocate(word_size) == NULL, 2269 "Don't need to expand"); 2270 MutexLockerEx cl(SpaceManager::expand_lock(), Mutex::_no_safepoint_check_flag); 2271 2272 if (log_is_enabled(Trace, gc, metaspace, freelist)) { 2273 size_t words_left = 0; 2274 size_t words_used = 0; 2275 if (current_chunk() != NULL) { 2276 words_left = current_chunk()->free_word_size(); 2277 words_used = current_chunk()->used_word_size(); 2278 } 2279 log_trace(gc, metaspace, freelist)("SpaceManager::grow_and_allocate for " SIZE_FORMAT " words " SIZE_FORMAT " words used " SIZE_FORMAT " words left", 2280 word_size, words_used, words_left); 2281 } 2282 2283 // Get another chunk 2284 size_t chunk_word_size = calc_chunk_size(word_size); 2285 Metachunk* next = get_new_chunk(chunk_word_size); 2286 2287 MetaWord* mem = NULL; 2288 2289 // If a chunk was available, add it to the in-use chunk list 2290 // and do an allocation from it. 2291 if (next != NULL) { 2292 // Add to this manager's list of chunks in use. 2293 add_chunk(next, false); 2294 mem = next->allocate(word_size); 2295 } 2296 2297 // Track metaspace memory usage statistic. 2298 track_metaspace_memory_usage(); 2299 2300 return mem; 2301 } 2302 2303 void SpaceManager::print_on(outputStream* st) const { 2304 2305 for (ChunkIndex i = ZeroIndex; 2306 i < NumberOfInUseLists ; 2307 i = next_chunk_index(i) ) { 2308 st->print_cr(" chunks_in_use " PTR_FORMAT " chunk size " SIZE_FORMAT, 2309 p2i(chunks_in_use(i)), 2310 chunks_in_use(i) == NULL ? 0 : chunks_in_use(i)->word_size()); 2311 } 2312 st->print_cr(" waste: Small " SIZE_FORMAT " Medium " SIZE_FORMAT 2313 " Humongous " SIZE_FORMAT, 2314 sum_waste_in_chunks_in_use(SmallIndex), 2315 sum_waste_in_chunks_in_use(MediumIndex), 2316 sum_waste_in_chunks_in_use(HumongousIndex)); 2317 // block free lists 2318 if (block_freelists() != NULL) { 2319 st->print_cr("total in block free lists " SIZE_FORMAT, 2320 block_freelists()->total_size()); 2321 } 2322 } 2323 2324 SpaceManager::SpaceManager(Metaspace::MetadataType mdtype, 2325 Mutex* lock) : 2326 _mdtype(mdtype), 2327 _allocated_blocks_words(0), 2328 _allocated_chunks_words(0), 2329 _allocated_chunks_count(0), 2330 _block_freelists(NULL), 2331 _lock(lock) 2332 { 2333 initialize(); 2334 } 2335 2336 void SpaceManager::inc_size_metrics(size_t words) { 2337 assert_lock_strong(SpaceManager::expand_lock()); 2338 // Total of allocated Metachunks and allocated Metachunks count 2339 // for each SpaceManager 2340 _allocated_chunks_words = _allocated_chunks_words + words; 2341 _allocated_chunks_count++; 2342 // Global total of capacity in allocated Metachunks 2343 MetaspaceAux::inc_capacity(mdtype(), words); 2344 // Global total of allocated Metablocks. 2345 // used_words_slow() includes the overhead in each 2346 // Metachunk so include it in the used when the 2347 // Metachunk is first added (so only added once per 2348 // Metachunk). 2349 MetaspaceAux::inc_used(mdtype(), Metachunk::overhead()); 2350 } 2351 2352 void SpaceManager::inc_used_metrics(size_t words) { 2353 // Add to the per SpaceManager total 2354 Atomic::add_ptr(words, &_allocated_blocks_words); 2355 // Add to the global total 2356 MetaspaceAux::inc_used(mdtype(), words); 2357 } 2358 2359 void SpaceManager::dec_total_from_size_metrics() { 2360 MetaspaceAux::dec_capacity(mdtype(), allocated_chunks_words()); 2361 MetaspaceAux::dec_used(mdtype(), allocated_blocks_words()); 2362 // Also deduct the overhead per Metachunk 2363 MetaspaceAux::dec_used(mdtype(), allocated_chunks_count() * Metachunk::overhead()); 2364 } 2365 2366 void SpaceManager::initialize() { 2367 Metadebug::init_allocation_fail_alot_count(); 2368 for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) { 2369 _chunks_in_use[i] = NULL; 2370 } 2371 _current_chunk = NULL; 2372 log_trace(gc, metaspace, freelist)("SpaceManager(): " PTR_FORMAT, p2i(this)); 2373 } 2374 2375 SpaceManager::~SpaceManager() { 2376 // This call this->_lock which can't be done while holding expand_lock() 2377 assert(sum_capacity_in_chunks_in_use() == allocated_chunks_words(), 2378 "sum_capacity_in_chunks_in_use() " SIZE_FORMAT 2379 " allocated_chunks_words() " SIZE_FORMAT, 2380 sum_capacity_in_chunks_in_use(), allocated_chunks_words()); 2381 2382 MutexLockerEx fcl(SpaceManager::expand_lock(), 2383 Mutex::_no_safepoint_check_flag); 2384 2385 chunk_manager()->slow_locked_verify(); 2386 2387 dec_total_from_size_metrics(); 2388 2389 Log(gc, metaspace, freelist) log; 2390 if (log.is_trace()) { 2391 log.trace("~SpaceManager(): " PTR_FORMAT, p2i(this)); 2392 ResourceMark rm; 2393 locked_print_chunks_in_use_on(log.trace_stream()); 2394 if (block_freelists() != NULL) { 2395 block_freelists()->print_on(log.trace_stream()); 2396 } 2397 } 2398 2399 // Add all the chunks in use by this space manager 2400 // to the global list of free chunks. 2401 2402 // Follow each list of chunks-in-use and add them to the 2403 // free lists. Each list is NULL terminated. 2404 2405 for (ChunkIndex i = ZeroIndex; i <= HumongousIndex; i = next_chunk_index(i)) { 2406 Metachunk* chunks = chunks_in_use(i); 2407 chunk_manager()->return_chunk_list(i, chunks); 2408 set_chunks_in_use(i, NULL); 2409 } 2410 2411 chunk_manager()->slow_locked_verify(); 2412 2413 if (_block_freelists != NULL) { 2414 delete _block_freelists; 2415 } 2416 } 2417 2418 void SpaceManager::deallocate(MetaWord* p, size_t word_size) { 2419 assert_lock_strong(_lock); 2420 // Allocations and deallocations are in raw_word_size 2421 size_t raw_word_size = get_allocation_word_size(word_size); 2422 // Lazily create a block_freelist 2423 if (block_freelists() == NULL) { 2424 _block_freelists = new BlockFreelist(); 2425 } 2426 block_freelists()->return_block(p, raw_word_size); 2427 } 2428 2429 // Adds a chunk to the list of chunks in use. 2430 void SpaceManager::add_chunk(Metachunk* new_chunk, bool make_current) { 2431 2432 assert(new_chunk != NULL, "Should not be NULL"); 2433 assert(new_chunk->next() == NULL, "Should not be on a list"); 2434 2435 new_chunk->reset_empty(); 2436 2437 // Find the correct list and and set the current 2438 // chunk for that list. 2439 ChunkIndex index = chunk_manager()->list_index(new_chunk->word_size()); 2440 2441 if (index != HumongousIndex) { 2442 retire_current_chunk(); 2443 set_current_chunk(new_chunk); 2444 new_chunk->set_next(chunks_in_use(index)); 2445 set_chunks_in_use(index, new_chunk); 2446 } else { 2447 // For null class loader data and DumpSharedSpaces, the first chunk isn't 2448 // small, so small will be null. Link this first chunk as the current 2449 // chunk. 2450 if (make_current) { 2451 // Set as the current chunk but otherwise treat as a humongous chunk. 2452 set_current_chunk(new_chunk); 2453 } 2454 // Link at head. The _current_chunk only points to a humongous chunk for 2455 // the null class loader metaspace (class and data virtual space managers) 2456 // any humongous chunks so will not point to the tail 2457 // of the humongous chunks list. 2458 new_chunk->set_next(chunks_in_use(HumongousIndex)); 2459 set_chunks_in_use(HumongousIndex, new_chunk); 2460 2461 assert(new_chunk->word_size() > medium_chunk_size(), "List inconsistency"); 2462 } 2463 2464 // Add to the running sum of capacity 2465 inc_size_metrics(new_chunk->word_size()); 2466 2467 assert(new_chunk->is_empty(), "Not ready for reuse"); 2468 Log(gc, metaspace, freelist) log; 2469 if (log.is_trace()) { 2470 log.trace("SpaceManager::add_chunk: " SIZE_FORMAT ") ", sum_count_in_chunks_in_use()); 2471 ResourceMark rm; 2472 outputStream* out = log.trace_stream(); 2473 new_chunk->print_on(out); 2474 chunk_manager()->locked_print_free_chunks(out); 2475 } 2476 } 2477 2478 void SpaceManager::retire_current_chunk() { 2479 if (current_chunk() != NULL) { 2480 size_t remaining_words = current_chunk()->free_word_size(); 2481 if (remaining_words >= BlockFreelist::min_dictionary_size()) { 2482 MetaWord* ptr = current_chunk()->allocate(remaining_words); 2483 deallocate(ptr, remaining_words); 2484 inc_used_metrics(remaining_words); 2485 } 2486 } 2487 } 2488 2489 Metachunk* SpaceManager::get_new_chunk(size_t chunk_word_size) { 2490 // Get a chunk from the chunk freelist 2491 Metachunk* next = chunk_manager()->chunk_freelist_allocate(chunk_word_size); 2492 2493 if (next == NULL) { 2494 next = vs_list()->get_new_chunk(chunk_word_size, 2495 medium_chunk_bunch()); 2496 } 2497 2498 Log(gc, metaspace, alloc) log; 2499 if (log.is_debug() && next != NULL && 2500 SpaceManager::is_humongous(next->word_size())) { 2501 log.debug(" new humongous chunk word size " PTR_FORMAT, next->word_size()); 2502 } 2503 2504 return next; 2505 } 2506 2507 /* 2508 * The policy is to allocate up to _small_chunk_limit small chunks 2509 * after which only medium chunks are allocated. This is done to 2510 * reduce fragmentation. In some cases, this can result in a lot 2511 * of small chunks being allocated to the point where it's not 2512 * possible to expand. If this happens, there may be no medium chunks 2513 * available and OOME would be thrown. Instead of doing that, 2514 * if the allocation request size fits in a small chunk, an attempt 2515 * will be made to allocate a small chunk. 2516 */ 2517 MetaWord* SpaceManager::get_small_chunk_and_allocate(size_t word_size) { 2518 size_t raw_word_size = get_allocation_word_size(word_size); 2519 2520 if (raw_word_size + Metachunk::overhead() > small_chunk_size()) { 2521 return NULL; 2522 } 2523 2524 MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag); 2525 MutexLockerEx cl1(expand_lock(), Mutex::_no_safepoint_check_flag); 2526 2527 Metachunk* chunk = chunk_manager()->chunk_freelist_allocate(small_chunk_size()); 2528 2529 MetaWord* mem = NULL; 2530 2531 if (chunk != NULL) { 2532 // Add chunk to the in-use chunk list and do an allocation from it. 2533 // Add to this manager's list of chunks in use. 2534 add_chunk(chunk, false); 2535 mem = chunk->allocate(raw_word_size); 2536 2537 inc_used_metrics(raw_word_size); 2538 2539 // Track metaspace memory usage statistic. 2540 track_metaspace_memory_usage(); 2541 } 2542 2543 return mem; 2544 } 2545 2546 MetaWord* SpaceManager::allocate(size_t word_size) { 2547 MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag); 2548 size_t raw_word_size = get_allocation_word_size(word_size); 2549 BlockFreelist* fl = block_freelists(); 2550 MetaWord* p = NULL; 2551 // Allocation from the dictionary is expensive in the sense that 2552 // the dictionary has to be searched for a size. Don't allocate 2553 // from the dictionary until it starts to get fat. Is this 2554 // a reasonable policy? Maybe an skinny dictionary is fast enough 2555 // for allocations. Do some profiling. JJJ 2556 if (fl != NULL && fl->total_size() > allocation_from_dictionary_limit) { 2557 p = fl->get_block(raw_word_size); 2558 } 2559 if (p == NULL) { 2560 p = allocate_work(raw_word_size); 2561 } 2562 2563 return p; 2564 } 2565 2566 // Returns the address of spaced allocated for "word_size". 2567 // This methods does not know about blocks (Metablocks) 2568 MetaWord* SpaceManager::allocate_work(size_t word_size) { 2569 assert_lock_strong(_lock); 2570 #ifdef ASSERT 2571 if (Metadebug::test_metadata_failure()) { 2572 return NULL; 2573 } 2574 #endif 2575 // Is there space in the current chunk? 2576 MetaWord* result = NULL; 2577 2578 // For DumpSharedSpaces, only allocate out of the current chunk which is 2579 // never null because we gave it the size we wanted. Caller reports out 2580 // of memory if this returns null. 2581 if (DumpSharedSpaces) { 2582 assert(current_chunk() != NULL, "should never happen"); 2583 inc_used_metrics(word_size); 2584 return current_chunk()->allocate(word_size); // caller handles null result 2585 } 2586 2587 if (current_chunk() != NULL) { 2588 result = current_chunk()->allocate(word_size); 2589 } 2590 2591 if (result == NULL) { 2592 result = grow_and_allocate(word_size); 2593 } 2594 2595 if (result != NULL) { 2596 inc_used_metrics(word_size); 2597 assert(result != (MetaWord*) chunks_in_use(MediumIndex), 2598 "Head of the list is being allocated"); 2599 } 2600 2601 return result; 2602 } 2603 2604 void SpaceManager::verify() { 2605 // If there are blocks in the dictionary, then 2606 // verification of chunks does not work since 2607 // being in the dictionary alters a chunk. 2608 if (block_freelists() != NULL && block_freelists()->total_size() == 0) { 2609 for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) { 2610 Metachunk* curr = chunks_in_use(i); 2611 while (curr != NULL) { 2612 curr->verify(); 2613 verify_chunk_size(curr); 2614 curr = curr->next(); 2615 } 2616 } 2617 } 2618 } 2619 2620 void SpaceManager::verify_chunk_size(Metachunk* chunk) { 2621 assert(is_humongous(chunk->word_size()) || 2622 chunk->word_size() == medium_chunk_size() || 2623 chunk->word_size() == small_chunk_size() || 2624 chunk->word_size() == specialized_chunk_size(), 2625 "Chunk size is wrong"); 2626 return; 2627 } 2628 2629 #ifdef ASSERT 2630 void SpaceManager::verify_allocated_blocks_words() { 2631 // Verification is only guaranteed at a safepoint. 2632 assert(SafepointSynchronize::is_at_safepoint() || !Universe::is_fully_initialized(), 2633 "Verification can fail if the applications is running"); 2634 assert(allocated_blocks_words() == sum_used_in_chunks_in_use(), 2635 "allocation total is not consistent " SIZE_FORMAT 2636 " vs " SIZE_FORMAT, 2637 allocated_blocks_words(), sum_used_in_chunks_in_use()); 2638 } 2639 2640 #endif 2641 2642 void SpaceManager::dump(outputStream* const out) const { 2643 size_t curr_total = 0; 2644 size_t waste = 0; 2645 uint i = 0; 2646 size_t used = 0; 2647 size_t capacity = 0; 2648 2649 // Add up statistics for all chunks in this SpaceManager. 2650 for (ChunkIndex index = ZeroIndex; 2651 index < NumberOfInUseLists; 2652 index = next_chunk_index(index)) { 2653 for (Metachunk* curr = chunks_in_use(index); 2654 curr != NULL; 2655 curr = curr->next()) { 2656 out->print("%d) ", i++); 2657 curr->print_on(out); 2658 curr_total += curr->word_size(); 2659 used += curr->used_word_size(); 2660 capacity += curr->word_size(); 2661 waste += curr->free_word_size() + curr->overhead();; 2662 } 2663 } 2664 2665 if (log_is_enabled(Trace, gc, metaspace, freelist)) { 2666 if (block_freelists() != NULL) block_freelists()->print_on(out); 2667 } 2668 2669 size_t free = current_chunk() == NULL ? 0 : current_chunk()->free_word_size(); 2670 // Free space isn't wasted. 2671 waste -= free; 2672 2673 out->print_cr("total of all chunks " SIZE_FORMAT " used " SIZE_FORMAT 2674 " free " SIZE_FORMAT " capacity " SIZE_FORMAT 2675 " waste " SIZE_FORMAT, curr_total, used, free, capacity, waste); 2676 } 2677 2678 // MetaspaceAux 2679 2680 2681 size_t MetaspaceAux::_capacity_words[] = {0, 0}; 2682 size_t MetaspaceAux::_used_words[] = {0, 0}; 2683 2684 size_t MetaspaceAux::free_bytes(Metaspace::MetadataType mdtype) { 2685 VirtualSpaceList* list = Metaspace::get_space_list(mdtype); 2686 return list == NULL ? 0 : list->free_bytes(); 2687 } 2688 2689 size_t MetaspaceAux::free_bytes() { 2690 return free_bytes(Metaspace::ClassType) + free_bytes(Metaspace::NonClassType); 2691 } 2692 2693 void MetaspaceAux::dec_capacity(Metaspace::MetadataType mdtype, size_t words) { 2694 assert_lock_strong(SpaceManager::expand_lock()); 2695 assert(words <= capacity_words(mdtype), 2696 "About to decrement below 0: words " SIZE_FORMAT 2697 " is greater than _capacity_words[%u] " SIZE_FORMAT, 2698 words, mdtype, capacity_words(mdtype)); 2699 _capacity_words[mdtype] -= words; 2700 } 2701 2702 void MetaspaceAux::inc_capacity(Metaspace::MetadataType mdtype, size_t words) { 2703 assert_lock_strong(SpaceManager::expand_lock()); 2704 // Needs to be atomic 2705 _capacity_words[mdtype] += words; 2706 } 2707 2708 void MetaspaceAux::dec_used(Metaspace::MetadataType mdtype, size_t words) { 2709 assert(words <= used_words(mdtype), 2710 "About to decrement below 0: words " SIZE_FORMAT 2711 " is greater than _used_words[%u] " SIZE_FORMAT, 2712 words, mdtype, used_words(mdtype)); 2713 // For CMS deallocation of the Metaspaces occurs during the 2714 // sweep which is a concurrent phase. Protection by the expand_lock() 2715 // is not enough since allocation is on a per Metaspace basis 2716 // and protected by the Metaspace lock. 2717 jlong minus_words = (jlong) - (jlong) words; 2718 Atomic::add_ptr(minus_words, &_used_words[mdtype]); 2719 } 2720 2721 void MetaspaceAux::inc_used(Metaspace::MetadataType mdtype, size_t words) { 2722 // _used_words tracks allocations for 2723 // each piece of metadata. Those allocations are 2724 // generally done concurrently by different application 2725 // threads so must be done atomically. 2726 Atomic::add_ptr(words, &_used_words[mdtype]); 2727 } 2728 2729 size_t MetaspaceAux::used_bytes_slow(Metaspace::MetadataType mdtype) { 2730 size_t used = 0; 2731 ClassLoaderDataGraphMetaspaceIterator iter; 2732 while (iter.repeat()) { 2733 Metaspace* msp = iter.get_next(); 2734 // Sum allocated_blocks_words for each metaspace 2735 if (msp != NULL) { 2736 used += msp->used_words_slow(mdtype); 2737 } 2738 } 2739 return used * BytesPerWord; 2740 } 2741 2742 size_t MetaspaceAux::free_bytes_slow(Metaspace::MetadataType mdtype) { 2743 size_t free = 0; 2744 ClassLoaderDataGraphMetaspaceIterator iter; 2745 while (iter.repeat()) { 2746 Metaspace* msp = iter.get_next(); 2747 if (msp != NULL) { 2748 free += msp->free_words_slow(mdtype); 2749 } 2750 } 2751 return free * BytesPerWord; 2752 } 2753 2754 size_t MetaspaceAux::capacity_bytes_slow(Metaspace::MetadataType mdtype) { 2755 if ((mdtype == Metaspace::ClassType) && !Metaspace::using_class_space()) { 2756 return 0; 2757 } 2758 // Don't count the space in the freelists. That space will be 2759 // added to the capacity calculation as needed. 2760 size_t capacity = 0; 2761 ClassLoaderDataGraphMetaspaceIterator iter; 2762 while (iter.repeat()) { 2763 Metaspace* msp = iter.get_next(); 2764 if (msp != NULL) { 2765 capacity += msp->capacity_words_slow(mdtype); 2766 } 2767 } 2768 return capacity * BytesPerWord; 2769 } 2770 2771 size_t MetaspaceAux::capacity_bytes_slow() { 2772 #ifdef PRODUCT 2773 // Use capacity_bytes() in PRODUCT instead of this function. 2774 guarantee(false, "Should not call capacity_bytes_slow() in the PRODUCT"); 2775 #endif 2776 size_t class_capacity = capacity_bytes_slow(Metaspace::ClassType); 2777 size_t non_class_capacity = capacity_bytes_slow(Metaspace::NonClassType); 2778 assert(capacity_bytes() == class_capacity + non_class_capacity, 2779 "bad accounting: capacity_bytes() " SIZE_FORMAT 2780 " class_capacity + non_class_capacity " SIZE_FORMAT 2781 " class_capacity " SIZE_FORMAT " non_class_capacity " SIZE_FORMAT, 2782 capacity_bytes(), class_capacity + non_class_capacity, 2783 class_capacity, non_class_capacity); 2784 2785 return class_capacity + non_class_capacity; 2786 } 2787 2788 size_t MetaspaceAux::reserved_bytes(Metaspace::MetadataType mdtype) { 2789 VirtualSpaceList* list = Metaspace::get_space_list(mdtype); 2790 return list == NULL ? 0 : list->reserved_bytes(); 2791 } 2792 2793 size_t MetaspaceAux::committed_bytes(Metaspace::MetadataType mdtype) { 2794 VirtualSpaceList* list = Metaspace::get_space_list(mdtype); 2795 return list == NULL ? 0 : list->committed_bytes(); 2796 } 2797 2798 size_t MetaspaceAux::min_chunk_size_words() { return Metaspace::first_chunk_word_size(); } 2799 2800 size_t MetaspaceAux::free_chunks_total_words(Metaspace::MetadataType mdtype) { 2801 ChunkManager* chunk_manager = Metaspace::get_chunk_manager(mdtype); 2802 if (chunk_manager == NULL) { 2803 return 0; 2804 } 2805 chunk_manager->slow_verify(); 2806 return chunk_manager->free_chunks_total_words(); 2807 } 2808 2809 size_t MetaspaceAux::free_chunks_total_bytes(Metaspace::MetadataType mdtype) { 2810 return free_chunks_total_words(mdtype) * BytesPerWord; 2811 } 2812 2813 size_t MetaspaceAux::free_chunks_total_words() { 2814 return free_chunks_total_words(Metaspace::ClassType) + 2815 free_chunks_total_words(Metaspace::NonClassType); 2816 } 2817 2818 size_t MetaspaceAux::free_chunks_total_bytes() { 2819 return free_chunks_total_words() * BytesPerWord; 2820 } 2821 2822 bool MetaspaceAux::has_chunk_free_list(Metaspace::MetadataType mdtype) { 2823 return Metaspace::get_chunk_manager(mdtype) != NULL; 2824 } 2825 2826 MetaspaceChunkFreeListSummary MetaspaceAux::chunk_free_list_summary(Metaspace::MetadataType mdtype) { 2827 if (!has_chunk_free_list(mdtype)) { 2828 return MetaspaceChunkFreeListSummary(); 2829 } 2830 2831 const ChunkManager* cm = Metaspace::get_chunk_manager(mdtype); 2832 return cm->chunk_free_list_summary(); 2833 } 2834 2835 void MetaspaceAux::print_metaspace_change(size_t prev_metadata_used) { 2836 log_info(gc, metaspace)("Metaspace: " SIZE_FORMAT "K->" SIZE_FORMAT "K(" SIZE_FORMAT "K)", 2837 prev_metadata_used/K, used_bytes()/K, reserved_bytes()/K); 2838 } 2839 2840 void MetaspaceAux::print_on(outputStream* out) { 2841 Metaspace::MetadataType nct = Metaspace::NonClassType; 2842 2843 out->print_cr(" Metaspace " 2844 "used " SIZE_FORMAT "K, " 2845 "capacity " SIZE_FORMAT "K, " 2846 "committed " SIZE_FORMAT "K, " 2847 "reserved " SIZE_FORMAT "K", 2848 used_bytes()/K, 2849 capacity_bytes()/K, 2850 committed_bytes()/K, 2851 reserved_bytes()/K); 2852 2853 if (Metaspace::using_class_space()) { 2854 Metaspace::MetadataType ct = Metaspace::ClassType; 2855 out->print_cr(" class space " 2856 "used " SIZE_FORMAT "K, " 2857 "capacity " SIZE_FORMAT "K, " 2858 "committed " SIZE_FORMAT "K, " 2859 "reserved " SIZE_FORMAT "K", 2860 used_bytes(ct)/K, 2861 capacity_bytes(ct)/K, 2862 committed_bytes(ct)/K, 2863 reserved_bytes(ct)/K); 2864 } 2865 } 2866 2867 // Print information for class space and data space separately. 2868 // This is almost the same as above. 2869 void MetaspaceAux::print_on(outputStream* out, Metaspace::MetadataType mdtype) { 2870 size_t free_chunks_capacity_bytes = free_chunks_total_bytes(mdtype); 2871 size_t capacity_bytes = capacity_bytes_slow(mdtype); 2872 size_t used_bytes = used_bytes_slow(mdtype); 2873 size_t free_bytes = free_bytes_slow(mdtype); 2874 size_t used_and_free = used_bytes + free_bytes + 2875 free_chunks_capacity_bytes; 2876 out->print_cr(" Chunk accounting: used in chunks " SIZE_FORMAT 2877 "K + unused in chunks " SIZE_FORMAT "K + " 2878 " capacity in free chunks " SIZE_FORMAT "K = " SIZE_FORMAT 2879 "K capacity in allocated chunks " SIZE_FORMAT "K", 2880 used_bytes / K, 2881 free_bytes / K, 2882 free_chunks_capacity_bytes / K, 2883 used_and_free / K, 2884 capacity_bytes / K); 2885 // Accounting can only be correct if we got the values during a safepoint 2886 assert(!SafepointSynchronize::is_at_safepoint() || used_and_free == capacity_bytes, "Accounting is wrong"); 2887 } 2888 2889 // Print total fragmentation for class metaspaces 2890 void MetaspaceAux::print_class_waste(outputStream* out) { 2891 assert(Metaspace::using_class_space(), "class metaspace not used"); 2892 size_t cls_specialized_waste = 0, cls_small_waste = 0, cls_medium_waste = 0; 2893 size_t cls_specialized_count = 0, cls_small_count = 0, cls_medium_count = 0, cls_humongous_count = 0; 2894 ClassLoaderDataGraphMetaspaceIterator iter; 2895 while (iter.repeat()) { 2896 Metaspace* msp = iter.get_next(); 2897 if (msp != NULL) { 2898 cls_specialized_waste += msp->class_vsm()->sum_waste_in_chunks_in_use(SpecializedIndex); 2899 cls_specialized_count += msp->class_vsm()->sum_count_in_chunks_in_use(SpecializedIndex); 2900 cls_small_waste += msp->class_vsm()->sum_waste_in_chunks_in_use(SmallIndex); 2901 cls_small_count += msp->class_vsm()->sum_count_in_chunks_in_use(SmallIndex); 2902 cls_medium_waste += msp->class_vsm()->sum_waste_in_chunks_in_use(MediumIndex); 2903 cls_medium_count += msp->class_vsm()->sum_count_in_chunks_in_use(MediumIndex); 2904 cls_humongous_count += msp->class_vsm()->sum_count_in_chunks_in_use(HumongousIndex); 2905 } 2906 } 2907 out->print_cr(" class: " SIZE_FORMAT " specialized(s) " SIZE_FORMAT ", " 2908 SIZE_FORMAT " small(s) " SIZE_FORMAT ", " 2909 SIZE_FORMAT " medium(s) " SIZE_FORMAT ", " 2910 "large count " SIZE_FORMAT, 2911 cls_specialized_count, cls_specialized_waste, 2912 cls_small_count, cls_small_waste, 2913 cls_medium_count, cls_medium_waste, cls_humongous_count); 2914 } 2915 2916 // Print total fragmentation for data and class metaspaces separately 2917 void MetaspaceAux::print_waste(outputStream* out) { 2918 size_t specialized_waste = 0, small_waste = 0, medium_waste = 0; 2919 size_t specialized_count = 0, small_count = 0, medium_count = 0, humongous_count = 0; 2920 2921 ClassLoaderDataGraphMetaspaceIterator iter; 2922 while (iter.repeat()) { 2923 Metaspace* msp = iter.get_next(); 2924 if (msp != NULL) { 2925 specialized_waste += msp->vsm()->sum_waste_in_chunks_in_use(SpecializedIndex); 2926 specialized_count += msp->vsm()->sum_count_in_chunks_in_use(SpecializedIndex); 2927 small_waste += msp->vsm()->sum_waste_in_chunks_in_use(SmallIndex); 2928 small_count += msp->vsm()->sum_count_in_chunks_in_use(SmallIndex); 2929 medium_waste += msp->vsm()->sum_waste_in_chunks_in_use(MediumIndex); 2930 medium_count += msp->vsm()->sum_count_in_chunks_in_use(MediumIndex); 2931 humongous_count += msp->vsm()->sum_count_in_chunks_in_use(HumongousIndex); 2932 } 2933 } 2934 out->print_cr("Total fragmentation waste (words) doesn't count free space"); 2935 out->print_cr(" data: " SIZE_FORMAT " specialized(s) " SIZE_FORMAT ", " 2936 SIZE_FORMAT " small(s) " SIZE_FORMAT ", " 2937 SIZE_FORMAT " medium(s) " SIZE_FORMAT ", " 2938 "large count " SIZE_FORMAT, 2939 specialized_count, specialized_waste, small_count, 2940 small_waste, medium_count, medium_waste, humongous_count); 2941 if (Metaspace::using_class_space()) { 2942 print_class_waste(out); 2943 } 2944 } 2945 2946 // Dump global metaspace things from the end of ClassLoaderDataGraph 2947 void MetaspaceAux::dump(outputStream* out) { 2948 out->print_cr("All Metaspace:"); 2949 out->print("data space: "); print_on(out, Metaspace::NonClassType); 2950 out->print("class space: "); print_on(out, Metaspace::ClassType); 2951 print_waste(out); 2952 } 2953 2954 void MetaspaceAux::verify_free_chunks() { 2955 Metaspace::chunk_manager_metadata()->verify(); 2956 if (Metaspace::using_class_space()) { 2957 Metaspace::chunk_manager_class()->verify(); 2958 } 2959 } 2960 2961 void MetaspaceAux::verify_capacity() { 2962 #ifdef ASSERT 2963 size_t running_sum_capacity_bytes = capacity_bytes(); 2964 // For purposes of the running sum of capacity, verify against capacity 2965 size_t capacity_in_use_bytes = capacity_bytes_slow(); 2966 assert(running_sum_capacity_bytes == capacity_in_use_bytes, 2967 "capacity_words() * BytesPerWord " SIZE_FORMAT 2968 " capacity_bytes_slow()" SIZE_FORMAT, 2969 running_sum_capacity_bytes, capacity_in_use_bytes); 2970 for (Metaspace::MetadataType i = Metaspace::ClassType; 2971 i < Metaspace:: MetadataTypeCount; 2972 i = (Metaspace::MetadataType)(i + 1)) { 2973 size_t capacity_in_use_bytes = capacity_bytes_slow(i); 2974 assert(capacity_bytes(i) == capacity_in_use_bytes, 2975 "capacity_bytes(%u) " SIZE_FORMAT 2976 " capacity_bytes_slow(%u)" SIZE_FORMAT, 2977 i, capacity_bytes(i), i, capacity_in_use_bytes); 2978 } 2979 #endif 2980 } 2981 2982 void MetaspaceAux::verify_used() { 2983 #ifdef ASSERT 2984 size_t running_sum_used_bytes = used_bytes(); 2985 // For purposes of the running sum of used, verify against used 2986 size_t used_in_use_bytes = used_bytes_slow(); 2987 assert(used_bytes() == used_in_use_bytes, 2988 "used_bytes() " SIZE_FORMAT 2989 " used_bytes_slow()" SIZE_FORMAT, 2990 used_bytes(), used_in_use_bytes); 2991 for (Metaspace::MetadataType i = Metaspace::ClassType; 2992 i < Metaspace:: MetadataTypeCount; 2993 i = (Metaspace::MetadataType)(i + 1)) { 2994 size_t used_in_use_bytes = used_bytes_slow(i); 2995 assert(used_bytes(i) == used_in_use_bytes, 2996 "used_bytes(%u) " SIZE_FORMAT 2997 " used_bytes_slow(%u)" SIZE_FORMAT, 2998 i, used_bytes(i), i, used_in_use_bytes); 2999 } 3000 #endif 3001 } 3002 3003 void MetaspaceAux::verify_metrics() { 3004 verify_capacity(); 3005 verify_used(); 3006 } 3007 3008 3009 // Metaspace methods 3010 3011 size_t Metaspace::_first_chunk_word_size = 0; 3012 size_t Metaspace::_first_class_chunk_word_size = 0; 3013 3014 size_t Metaspace::_commit_alignment = 0; 3015 size_t Metaspace::_reserve_alignment = 0; 3016 3017 Metaspace::Metaspace(Mutex* lock, MetaspaceType type) { 3018 initialize(lock, type); 3019 } 3020 3021 Metaspace::~Metaspace() { 3022 delete _vsm; 3023 if (using_class_space()) { 3024 delete _class_vsm; 3025 } 3026 } 3027 3028 VirtualSpaceList* Metaspace::_space_list = NULL; 3029 VirtualSpaceList* Metaspace::_class_space_list = NULL; 3030 3031 ChunkManager* Metaspace::_chunk_manager_metadata = NULL; 3032 ChunkManager* Metaspace::_chunk_manager_class = NULL; 3033 3034 #define VIRTUALSPACEMULTIPLIER 2 3035 3036 #ifdef _LP64 3037 static const uint64_t UnscaledClassSpaceMax = (uint64_t(max_juint) + 1); 3038 3039 void Metaspace::set_narrow_klass_base_and_shift(address metaspace_base, address cds_base) { 3040 // Figure out the narrow_klass_base and the narrow_klass_shift. The 3041 // narrow_klass_base is the lower of the metaspace base and the cds base 3042 // (if cds is enabled). The narrow_klass_shift depends on the distance 3043 // between the lower base and higher address. 3044 address lower_base; 3045 address higher_address; 3046 #if INCLUDE_CDS 3047 if (UseSharedSpaces) { 3048 higher_address = MAX2((address)(cds_base + FileMapInfo::shared_spaces_size()), 3049 (address)(metaspace_base + compressed_class_space_size())); 3050 lower_base = MIN2(metaspace_base, cds_base); 3051 } else 3052 #endif 3053 { 3054 higher_address = metaspace_base + compressed_class_space_size(); 3055 lower_base = metaspace_base; 3056 3057 uint64_t klass_encoding_max = UnscaledClassSpaceMax << LogKlassAlignmentInBytes; 3058 // If compressed class space fits in lower 32G, we don't need a base. 3059 if (higher_address <= (address)klass_encoding_max) { 3060 lower_base = 0; // Effectively lower base is zero. 3061 } 3062 } 3063 3064 Universe::set_narrow_klass_base(lower_base); 3065 3066 if ((uint64_t)(higher_address - lower_base) <= UnscaledClassSpaceMax) { 3067 Universe::set_narrow_klass_shift(0); 3068 } else { 3069 assert(!UseSharedSpaces, "Cannot shift with UseSharedSpaces"); 3070 Universe::set_narrow_klass_shift(LogKlassAlignmentInBytes); 3071 } 3072 AOTLoader::set_narrow_klass_shift(); 3073 } 3074 3075 #if INCLUDE_CDS 3076 // Return TRUE if the specified metaspace_base and cds_base are close enough 3077 // to work with compressed klass pointers. 3078 bool Metaspace::can_use_cds_with_metaspace_addr(char* metaspace_base, address cds_base) { 3079 assert(cds_base != 0 && UseSharedSpaces, "Only use with CDS"); 3080 assert(UseCompressedClassPointers, "Only use with CompressedKlassPtrs"); 3081 address lower_base = MIN2((address)metaspace_base, cds_base); 3082 address higher_address = MAX2((address)(cds_base + FileMapInfo::shared_spaces_size()), 3083 (address)(metaspace_base + compressed_class_space_size())); 3084 return ((uint64_t)(higher_address - lower_base) <= UnscaledClassSpaceMax); 3085 } 3086 #endif 3087 3088 // Try to allocate the metaspace at the requested addr. 3089 void Metaspace::allocate_metaspace_compressed_klass_ptrs(char* requested_addr, address cds_base) { 3090 assert(using_class_space(), "called improperly"); 3091 assert(UseCompressedClassPointers, "Only use with CompressedKlassPtrs"); 3092 assert(compressed_class_space_size() < KlassEncodingMetaspaceMax, 3093 "Metaspace size is too big"); 3094 assert_is_aligned(requested_addr, _reserve_alignment); 3095 assert_is_aligned(cds_base, _reserve_alignment); 3096 assert_is_aligned(compressed_class_space_size(), _reserve_alignment); 3097 3098 // Don't use large pages for the class space. 3099 bool large_pages = false; 3100 3101 #if !(defined(AARCH64) || defined(AIX)) 3102 ReservedSpace metaspace_rs = ReservedSpace(compressed_class_space_size(), 3103 _reserve_alignment, 3104 large_pages, 3105 requested_addr); 3106 #else // AARCH64 3107 ReservedSpace metaspace_rs; 3108 3109 // Our compressed klass pointers may fit nicely into the lower 32 3110 // bits. 3111 if ((uint64_t)requested_addr + compressed_class_space_size() < 4*G) { 3112 metaspace_rs = ReservedSpace(compressed_class_space_size(), 3113 _reserve_alignment, 3114 large_pages, 3115 requested_addr); 3116 } 3117 3118 if (! metaspace_rs.is_reserved()) { 3119 // Aarch64: Try to align metaspace so that we can decode a compressed 3120 // klass with a single MOVK instruction. We can do this iff the 3121 // compressed class base is a multiple of 4G. 3122 // Aix: Search for a place where we can find memory. If we need to load 3123 // the base, 4G alignment is helpful, too. 3124 size_t increment = AARCH64_ONLY(4*)G; 3125 for (char *a = align_up(requested_addr, increment); 3126 a < (char*)(1024*G); 3127 a += increment) { 3128 if (a == (char *)(32*G)) { 3129 // Go faster from here on. Zero-based is no longer possible. 3130 increment = 4*G; 3131 } 3132 3133 #if INCLUDE_CDS 3134 if (UseSharedSpaces 3135 && ! can_use_cds_with_metaspace_addr(a, cds_base)) { 3136 // We failed to find an aligned base that will reach. Fall 3137 // back to using our requested addr. 3138 metaspace_rs = ReservedSpace(compressed_class_space_size(), 3139 _reserve_alignment, 3140 large_pages, 3141 requested_addr); 3142 break; 3143 } 3144 #endif 3145 3146 metaspace_rs = ReservedSpace(compressed_class_space_size(), 3147 _reserve_alignment, 3148 large_pages, 3149 a); 3150 if (metaspace_rs.is_reserved()) 3151 break; 3152 } 3153 } 3154 3155 #endif // AARCH64 3156 3157 if (!metaspace_rs.is_reserved()) { 3158 #if INCLUDE_CDS 3159 if (UseSharedSpaces) { 3160 size_t increment = align_up(1*G, _reserve_alignment); 3161 3162 // Keep trying to allocate the metaspace, increasing the requested_addr 3163 // by 1GB each time, until we reach an address that will no longer allow 3164 // use of CDS with compressed klass pointers. 3165 char *addr = requested_addr; 3166 while (!metaspace_rs.is_reserved() && (addr + increment > addr) && 3167 can_use_cds_with_metaspace_addr(addr + increment, cds_base)) { 3168 addr = addr + increment; 3169 metaspace_rs = ReservedSpace(compressed_class_space_size(), 3170 _reserve_alignment, large_pages, addr); 3171 } 3172 } 3173 #endif 3174 // If no successful allocation then try to allocate the space anywhere. If 3175 // that fails then OOM doom. At this point we cannot try allocating the 3176 // metaspace as if UseCompressedClassPointers is off because too much 3177 // initialization has happened that depends on UseCompressedClassPointers. 3178 // So, UseCompressedClassPointers cannot be turned off at this point. 3179 if (!metaspace_rs.is_reserved()) { 3180 metaspace_rs = ReservedSpace(compressed_class_space_size(), 3181 _reserve_alignment, large_pages); 3182 if (!metaspace_rs.is_reserved()) { 3183 vm_exit_during_initialization(err_msg("Could not allocate metaspace: " SIZE_FORMAT " bytes", 3184 compressed_class_space_size())); 3185 } 3186 } 3187 } 3188 3189 // If we got here then the metaspace got allocated. 3190 MemTracker::record_virtual_memory_type((address)metaspace_rs.base(), mtClass); 3191 3192 #if INCLUDE_CDS 3193 // Verify that we can use shared spaces. Otherwise, turn off CDS. 3194 if (UseSharedSpaces && !can_use_cds_with_metaspace_addr(metaspace_rs.base(), cds_base)) { 3195 FileMapInfo::stop_sharing_and_unmap( 3196 "Could not allocate metaspace at a compatible address"); 3197 } 3198 #endif 3199 set_narrow_klass_base_and_shift((address)metaspace_rs.base(), 3200 UseSharedSpaces ? (address)cds_base : 0); 3201 3202 initialize_class_space(metaspace_rs); 3203 3204 if (log_is_enabled(Trace, gc, metaspace)) { 3205 Log(gc, metaspace) log; 3206 ResourceMark rm; 3207 print_compressed_class_space(log.trace_stream(), requested_addr); 3208 } 3209 } 3210 3211 void Metaspace::print_compressed_class_space(outputStream* st, const char* requested_addr) { 3212 st->print_cr("Narrow klass base: " PTR_FORMAT ", Narrow klass shift: %d", 3213 p2i(Universe::narrow_klass_base()), Universe::narrow_klass_shift()); 3214 if (_class_space_list != NULL) { 3215 address base = (address)_class_space_list->current_virtual_space()->bottom(); 3216 st->print("Compressed class space size: " SIZE_FORMAT " Address: " PTR_FORMAT, 3217 compressed_class_space_size(), p2i(base)); 3218 if (requested_addr != 0) { 3219 st->print(" Req Addr: " PTR_FORMAT, p2i(requested_addr)); 3220 } 3221 st->cr(); 3222 } 3223 } 3224 3225 // For UseCompressedClassPointers the class space is reserved above the top of 3226 // the Java heap. The argument passed in is at the base of the compressed space. 3227 void Metaspace::initialize_class_space(ReservedSpace rs) { 3228 // The reserved space size may be bigger because of alignment, esp with UseLargePages 3229 assert(rs.size() >= CompressedClassSpaceSize, 3230 SIZE_FORMAT " != " SIZE_FORMAT, rs.size(), CompressedClassSpaceSize); 3231 assert(using_class_space(), "Must be using class space"); 3232 _class_space_list = new VirtualSpaceList(rs); 3233 _chunk_manager_class = new ChunkManager(ClassSpecializedChunk, ClassSmallChunk, ClassMediumChunk); 3234 3235 if (!_class_space_list->initialization_succeeded()) { 3236 vm_exit_during_initialization("Failed to setup compressed class space virtual space list."); 3237 } 3238 } 3239 3240 #endif 3241 3242 void Metaspace::ergo_initialize() { 3243 if (DumpSharedSpaces) { 3244 // Using large pages when dumping the shared archive is currently not implemented. 3245 FLAG_SET_ERGO(bool, UseLargePagesInMetaspace, false); 3246 } 3247 3248 size_t page_size = os::vm_page_size(); 3249 if (UseLargePages && UseLargePagesInMetaspace) { 3250 page_size = os::large_page_size(); 3251 } 3252 3253 _commit_alignment = page_size; 3254 _reserve_alignment = MAX2(page_size, (size_t)os::vm_allocation_granularity()); 3255 3256 // Do not use FLAG_SET_ERGO to update MaxMetaspaceSize, since this will 3257 // override if MaxMetaspaceSize was set on the command line or not. 3258 // This information is needed later to conform to the specification of the 3259 // java.lang.management.MemoryUsage API. 3260 // 3261 // Ideally, we would be able to set the default value of MaxMetaspaceSize in 3262 // globals.hpp to the aligned value, but this is not possible, since the 3263 // alignment depends on other flags being parsed. 3264 MaxMetaspaceSize = align_down_bounded(MaxMetaspaceSize, _reserve_alignment); 3265 3266 if (MetaspaceSize > MaxMetaspaceSize) { 3267 MetaspaceSize = MaxMetaspaceSize; 3268 } 3269 3270 MetaspaceSize = align_down_bounded(MetaspaceSize, _commit_alignment); 3271 3272 assert(MetaspaceSize <= MaxMetaspaceSize, "MetaspaceSize should be limited by MaxMetaspaceSize"); 3273 3274 MinMetaspaceExpansion = align_down_bounded(MinMetaspaceExpansion, _commit_alignment); 3275 MaxMetaspaceExpansion = align_down_bounded(MaxMetaspaceExpansion, _commit_alignment); 3276 3277 CompressedClassSpaceSize = align_down_bounded(CompressedClassSpaceSize, _reserve_alignment); 3278 set_compressed_class_space_size(CompressedClassSpaceSize); 3279 } 3280 3281 void Metaspace::global_initialize() { 3282 MetaspaceGC::initialize(); 3283 3284 // Initialize the alignment for shared spaces. 3285 int max_alignment = os::vm_allocation_granularity(); 3286 size_t cds_total = 0; 3287 3288 MetaspaceShared::set_max_alignment(max_alignment); 3289 3290 if (DumpSharedSpaces) { 3291 #if INCLUDE_CDS 3292 MetaspaceShared::estimate_regions_size(); 3293 3294 SharedReadOnlySize = align_up(SharedReadOnlySize, max_alignment); 3295 SharedReadWriteSize = align_up(SharedReadWriteSize, max_alignment); 3296 SharedMiscDataSize = align_up(SharedMiscDataSize, max_alignment); 3297 SharedMiscCodeSize = align_up(SharedMiscCodeSize, max_alignment); 3298 3299 // Initialize with the sum of the shared space sizes. The read-only 3300 // and read write metaspace chunks will be allocated out of this and the 3301 // remainder is the misc code and data chunks. 3302 cds_total = FileMapInfo::shared_spaces_size(); 3303 cds_total = align_up(cds_total, _reserve_alignment); 3304 _space_list = new VirtualSpaceList(cds_total/wordSize); 3305 _chunk_manager_metadata = new ChunkManager(SpecializedChunk, SmallChunk, MediumChunk); 3306 3307 if (!_space_list->initialization_succeeded()) { 3308 vm_exit_during_initialization("Unable to dump shared archive.", NULL); 3309 } 3310 3311 #ifdef _LP64 3312 if (cds_total + compressed_class_space_size() > UnscaledClassSpaceMax) { 3313 vm_exit_during_initialization("Unable to dump shared archive.", 3314 err_msg("Size of archive (" SIZE_FORMAT ") + compressed class space (" 3315 SIZE_FORMAT ") == total (" SIZE_FORMAT ") is larger than compressed " 3316 "klass limit: " UINT64_FORMAT, cds_total, compressed_class_space_size(), 3317 cds_total + compressed_class_space_size(), UnscaledClassSpaceMax)); 3318 } 3319 3320 // Set the compressed klass pointer base so that decoding of these pointers works 3321 // properly when creating the shared archive. 3322 assert(UseCompressedOops && UseCompressedClassPointers, 3323 "UseCompressedOops and UseCompressedClassPointers must be set"); 3324 Universe::set_narrow_klass_base((address)_space_list->current_virtual_space()->bottom()); 3325 log_develop_trace(gc, metaspace)("Setting_narrow_klass_base to Address: " PTR_FORMAT, 3326 p2i(_space_list->current_virtual_space()->bottom())); 3327 3328 Universe::set_narrow_klass_shift(0); 3329 #endif // _LP64 3330 #endif // INCLUDE_CDS 3331 } else { 3332 #if INCLUDE_CDS 3333 if (UseSharedSpaces) { 3334 // If using shared space, open the file that contains the shared space 3335 // and map in the memory before initializing the rest of metaspace (so 3336 // the addresses don't conflict) 3337 address cds_address = NULL; 3338 FileMapInfo* mapinfo = new FileMapInfo(); 3339 3340 // Open the shared archive file, read and validate the header. If 3341 // initialization fails, shared spaces [UseSharedSpaces] are 3342 // disabled and the file is closed. 3343 // Map in spaces now also 3344 if (mapinfo->initialize() && MetaspaceShared::map_shared_spaces(mapinfo)) { 3345 cds_total = FileMapInfo::shared_spaces_size(); 3346 cds_address = (address)mapinfo->header()->region_addr(0); 3347 #ifdef _LP64 3348 if (using_class_space()) { 3349 char* cds_end = (char*)(cds_address + cds_total); 3350 cds_end = align_up(cds_end, _reserve_alignment); 3351 // If UseCompressedClassPointers is set then allocate the metaspace area 3352 // above the heap and above the CDS area (if it exists). 3353 allocate_metaspace_compressed_klass_ptrs(cds_end, cds_address); 3354 // Map the shared string space after compressed pointers 3355 // because it relies on compressed class pointers setting to work 3356 mapinfo->map_string_regions(); 3357 } 3358 #endif // _LP64 3359 } else { 3360 assert(!mapinfo->is_open() && !UseSharedSpaces, 3361 "archive file not closed or shared spaces not disabled."); 3362 } 3363 } 3364 #endif // INCLUDE_CDS 3365 3366 #ifdef _LP64 3367 if (!UseSharedSpaces && using_class_space()) { 3368 char* base = (char*)align_up(Universe::heap()->reserved_region().end(), _reserve_alignment); 3369 allocate_metaspace_compressed_klass_ptrs(base, 0); 3370 } 3371 #endif // _LP64 3372 3373 // Initialize these before initializing the VirtualSpaceList 3374 _first_chunk_word_size = InitialBootClassLoaderMetaspaceSize / BytesPerWord; 3375 _first_chunk_word_size = align_word_size_up(_first_chunk_word_size); 3376 // Make the first class chunk bigger than a medium chunk so it's not put 3377 // on the medium chunk list. The next chunk will be small and progress 3378 // from there. This size calculated by -version. 3379 _first_class_chunk_word_size = MIN2((size_t)MediumChunk*6, 3380 (CompressedClassSpaceSize/BytesPerWord)*2); 3381 _first_class_chunk_word_size = align_word_size_up(_first_class_chunk_word_size); 3382 // Arbitrarily set the initial virtual space to a multiple 3383 // of the boot class loader size. 3384 size_t word_size = VIRTUALSPACEMULTIPLIER * _first_chunk_word_size; 3385 word_size = align_up(word_size, Metaspace::reserve_alignment_words()); 3386 3387 // Initialize the list of virtual spaces. 3388 _space_list = new VirtualSpaceList(word_size); 3389 _chunk_manager_metadata = new ChunkManager(SpecializedChunk, SmallChunk, MediumChunk); 3390 3391 if (!_space_list->initialization_succeeded()) { 3392 vm_exit_during_initialization("Unable to setup metadata virtual space list.", NULL); 3393 } 3394 } 3395 3396 _tracer = new MetaspaceTracer(); 3397 } 3398 3399 void Metaspace::post_initialize() { 3400 MetaspaceGC::post_initialize(); 3401 } 3402 3403 void Metaspace::initialize_first_chunk(MetaspaceType type, MetadataType mdtype) { 3404 Metachunk* chunk = get_initialization_chunk(type, mdtype); 3405 if (chunk != NULL) { 3406 // Add to this manager's list of chunks in use and current_chunk(). 3407 get_space_manager(mdtype)->add_chunk(chunk, true); 3408 } 3409 } 3410 3411 Metachunk* Metaspace::get_initialization_chunk(MetaspaceType type, MetadataType mdtype) { 3412 size_t chunk_word_size = get_space_manager(mdtype)->get_initial_chunk_size(type); 3413 3414 // Get a chunk from the chunk freelist 3415 Metachunk* chunk = get_chunk_manager(mdtype)->chunk_freelist_allocate(chunk_word_size); 3416 3417 if (chunk == NULL) { 3418 chunk = get_space_list(mdtype)->get_new_chunk(chunk_word_size, 3419 get_space_manager(mdtype)->medium_chunk_bunch()); 3420 } 3421 3422 // For dumping shared archive, report error if allocation has failed. 3423 if (DumpSharedSpaces && chunk == NULL) { 3424 report_insufficient_metaspace(MetaspaceAux::committed_bytes() + chunk_word_size * BytesPerWord); 3425 } 3426 3427 return chunk; 3428 } 3429 3430 void Metaspace::verify_global_initialization() { 3431 assert(space_list() != NULL, "Metadata VirtualSpaceList has not been initialized"); 3432 assert(chunk_manager_metadata() != NULL, "Metadata ChunkManager has not been initialized"); 3433 3434 if (using_class_space()) { 3435 assert(class_space_list() != NULL, "Class VirtualSpaceList has not been initialized"); 3436 assert(chunk_manager_class() != NULL, "Class ChunkManager has not been initialized"); 3437 } 3438 } 3439 3440 void Metaspace::initialize(Mutex* lock, MetaspaceType type) { 3441 verify_global_initialization(); 3442 3443 // Allocate SpaceManager for metadata objects. 3444 _vsm = new SpaceManager(NonClassType, lock); 3445 3446 if (using_class_space()) { 3447 // Allocate SpaceManager for classes. 3448 _class_vsm = new SpaceManager(ClassType, lock); 3449 } 3450 3451 MutexLockerEx cl(SpaceManager::expand_lock(), Mutex::_no_safepoint_check_flag); 3452 3453 // Allocate chunk for metadata objects 3454 initialize_first_chunk(type, NonClassType); 3455 3456 // Allocate chunk for class metadata objects 3457 if (using_class_space()) { 3458 initialize_first_chunk(type, ClassType); 3459 } 3460 3461 _alloc_record_head = NULL; 3462 _alloc_record_tail = NULL; 3463 } 3464 3465 size_t Metaspace::align_word_size_up(size_t word_size) { 3466 size_t byte_size = word_size * wordSize; 3467 return ReservedSpace::allocation_align_size_up(byte_size) / wordSize; 3468 } 3469 3470 MetaWord* Metaspace::allocate(size_t word_size, MetadataType mdtype) { 3471 // DumpSharedSpaces doesn't use class metadata area (yet) 3472 // Also, don't use class_vsm() unless UseCompressedClassPointers is true. 3473 if (is_class_space_allocation(mdtype)) { 3474 return class_vsm()->allocate(word_size); 3475 } else { 3476 return vsm()->allocate(word_size); 3477 } 3478 } 3479 3480 MetaWord* Metaspace::expand_and_allocate(size_t word_size, MetadataType mdtype) { 3481 size_t delta_bytes = MetaspaceGC::delta_capacity_until_GC(word_size * BytesPerWord); 3482 assert(delta_bytes > 0, "Must be"); 3483 3484 size_t before = 0; 3485 size_t after = 0; 3486 MetaWord* res; 3487 bool incremented; 3488 3489 // Each thread increments the HWM at most once. Even if the thread fails to increment 3490 // the HWM, an allocation is still attempted. This is because another thread must then 3491 // have incremented the HWM and therefore the allocation might still succeed. 3492 do { 3493 incremented = MetaspaceGC::inc_capacity_until_GC(delta_bytes, &after, &before); 3494 res = allocate(word_size, mdtype); 3495 } while (!incremented && res == NULL); 3496 3497 if (incremented) { 3498 tracer()->report_gc_threshold(before, after, 3499 MetaspaceGCThresholdUpdater::ExpandAndAllocate); 3500 log_trace(gc, metaspace)("Increase capacity to GC from " SIZE_FORMAT " to " SIZE_FORMAT, before, after); 3501 } 3502 3503 return res; 3504 } 3505 3506 // Space allocated in the Metaspace. This may 3507 // be across several metadata virtual spaces. 3508 char* Metaspace::bottom() const { 3509 assert(DumpSharedSpaces, "only useful and valid for dumping shared spaces"); 3510 return (char*)vsm()->current_chunk()->bottom(); 3511 } 3512 3513 size_t Metaspace::used_words_slow(MetadataType mdtype) const { 3514 if (mdtype == ClassType) { 3515 return using_class_space() ? class_vsm()->sum_used_in_chunks_in_use() : 0; 3516 } else { 3517 return vsm()->sum_used_in_chunks_in_use(); // includes overhead! 3518 } 3519 } 3520 3521 size_t Metaspace::free_words_slow(MetadataType mdtype) const { 3522 if (mdtype == ClassType) { 3523 return using_class_space() ? class_vsm()->sum_free_in_chunks_in_use() : 0; 3524 } else { 3525 return vsm()->sum_free_in_chunks_in_use(); 3526 } 3527 } 3528 3529 // Space capacity in the Metaspace. It includes 3530 // space in the list of chunks from which allocations 3531 // have been made. Don't include space in the global freelist and 3532 // in the space available in the dictionary which 3533 // is already counted in some chunk. 3534 size_t Metaspace::capacity_words_slow(MetadataType mdtype) const { 3535 if (mdtype == ClassType) { 3536 return using_class_space() ? class_vsm()->sum_capacity_in_chunks_in_use() : 0; 3537 } else { 3538 return vsm()->sum_capacity_in_chunks_in_use(); 3539 } 3540 } 3541 3542 size_t Metaspace::used_bytes_slow(MetadataType mdtype) const { 3543 return used_words_slow(mdtype) * BytesPerWord; 3544 } 3545 3546 size_t Metaspace::capacity_bytes_slow(MetadataType mdtype) const { 3547 return capacity_words_slow(mdtype) * BytesPerWord; 3548 } 3549 3550 size_t Metaspace::allocated_blocks_bytes() const { 3551 return vsm()->allocated_blocks_bytes() + 3552 (using_class_space() ? class_vsm()->allocated_blocks_bytes() : 0); 3553 } 3554 3555 size_t Metaspace::allocated_chunks_bytes() const { 3556 return vsm()->allocated_chunks_bytes() + 3557 (using_class_space() ? class_vsm()->allocated_chunks_bytes() : 0); 3558 } 3559 3560 void Metaspace::deallocate(MetaWord* ptr, size_t word_size, bool is_class) { 3561 assert(!SafepointSynchronize::is_at_safepoint() 3562 || Thread::current()->is_VM_thread(), "should be the VM thread"); 3563 3564 if (DumpSharedSpaces && log_is_enabled(Info, cds)) { 3565 record_deallocation(ptr, vsm()->get_allocation_word_size(word_size)); 3566 } 3567 3568 MutexLockerEx ml(vsm()->lock(), Mutex::_no_safepoint_check_flag); 3569 3570 if (is_class && using_class_space()) { 3571 class_vsm()->deallocate(ptr, word_size); 3572 } else { 3573 vsm()->deallocate(ptr, word_size); 3574 } 3575 } 3576 3577 3578 MetaWord* Metaspace::allocate(ClassLoaderData* loader_data, size_t word_size, 3579 bool read_only, MetaspaceObj::Type type, TRAPS) { 3580 if (HAS_PENDING_EXCEPTION) { 3581 assert(false, "Should not allocate with exception pending"); 3582 return NULL; // caller does a CHECK_NULL too 3583 } 3584 3585 assert(loader_data != NULL, "Should never pass around a NULL loader_data. " 3586 "ClassLoaderData::the_null_class_loader_data() should have been used."); 3587 3588 // Allocate in metaspaces without taking out a lock, because it deadlocks 3589 // with the SymbolTable_lock. Dumping is single threaded for now. We'll have 3590 // to revisit this for application class data sharing. 3591 if (DumpSharedSpaces) { 3592 assert(type > MetaspaceObj::UnknownType && type < MetaspaceObj::_number_of_types, "sanity"); 3593 Metaspace* space = read_only ? loader_data->ro_metaspace() : loader_data->rw_metaspace(); 3594 MetaWord* result = space->allocate(word_size, NonClassType); 3595 if (result == NULL) { 3596 report_out_of_shared_space(read_only ? SharedReadOnly : SharedReadWrite); 3597 } 3598 if (log_is_enabled(Info, cds)) { 3599 space->record_allocation(result, type, space->vsm()->get_allocation_word_size(word_size)); 3600 } 3601 3602 // Zero initialize. 3603 Copy::fill_to_words((HeapWord*)result, word_size, 0); 3604 3605 return result; 3606 } 3607 3608 MetadataType mdtype = (type == MetaspaceObj::ClassType) ? ClassType : NonClassType; 3609 3610 // Try to allocate metadata. 3611 MetaWord* result = loader_data->metaspace_non_null()->allocate(word_size, mdtype); 3612 3613 if (result == NULL) { 3614 tracer()->report_metaspace_allocation_failure(loader_data, word_size, type, mdtype); 3615 3616 // Allocation failed. 3617 if (is_init_completed()) { 3618 // Only start a GC if the bootstrapping has completed. 3619 3620 // Try to clean out some memory and retry. 3621 result = Universe::heap()->collector_policy()->satisfy_failed_metadata_allocation( 3622 loader_data, word_size, mdtype); 3623 } 3624 } 3625 3626 if (result == NULL) { 3627 SpaceManager* sm; 3628 if (is_class_space_allocation(mdtype)) { 3629 sm = loader_data->metaspace_non_null()->class_vsm(); 3630 } else { 3631 sm = loader_data->metaspace_non_null()->vsm(); 3632 } 3633 3634 result = sm->get_small_chunk_and_allocate(word_size); 3635 3636 if (result == NULL) { 3637 report_metadata_oome(loader_data, word_size, type, mdtype, CHECK_NULL); 3638 } 3639 } 3640 3641 // Zero initialize. 3642 Copy::fill_to_words((HeapWord*)result, word_size, 0); 3643 3644 return result; 3645 } 3646 3647 size_t Metaspace::class_chunk_size(size_t word_size) { 3648 assert(using_class_space(), "Has to use class space"); 3649 return class_vsm()->calc_chunk_size(word_size); 3650 } 3651 3652 void Metaspace::report_metadata_oome(ClassLoaderData* loader_data, size_t word_size, MetaspaceObj::Type type, MetadataType mdtype, TRAPS) { 3653 tracer()->report_metadata_oom(loader_data, word_size, type, mdtype); 3654 3655 // If result is still null, we are out of memory. 3656 Log(gc, metaspace, freelist) log; 3657 if (log.is_info()) { 3658 log.info("Metaspace (%s) allocation failed for size " SIZE_FORMAT, 3659 is_class_space_allocation(mdtype) ? "class" : "data", word_size); 3660 ResourceMark rm; 3661 outputStream* out = log.info_stream(); 3662 if (loader_data->metaspace_or_null() != NULL) { 3663 loader_data->dump(out); 3664 } 3665 MetaspaceAux::dump(out); 3666 } 3667 3668 bool out_of_compressed_class_space = false; 3669 if (is_class_space_allocation(mdtype)) { 3670 Metaspace* metaspace = loader_data->metaspace_non_null(); 3671 out_of_compressed_class_space = 3672 MetaspaceAux::committed_bytes(Metaspace::ClassType) + 3673 (metaspace->class_chunk_size(word_size) * BytesPerWord) > 3674 CompressedClassSpaceSize; 3675 } 3676 3677 // -XX:+HeapDumpOnOutOfMemoryError and -XX:OnOutOfMemoryError support 3678 const char* space_string = out_of_compressed_class_space ? 3679 "Compressed class space" : "Metaspace"; 3680 3681 report_java_out_of_memory(space_string); 3682 3683 if (JvmtiExport::should_post_resource_exhausted()) { 3684 JvmtiExport::post_resource_exhausted( 3685 JVMTI_RESOURCE_EXHAUSTED_OOM_ERROR, 3686 space_string); 3687 } 3688 3689 if (!is_init_completed()) { 3690 vm_exit_during_initialization("OutOfMemoryError", space_string); 3691 } 3692 3693 if (out_of_compressed_class_space) { 3694 THROW_OOP(Universe::out_of_memory_error_class_metaspace()); 3695 } else { 3696 THROW_OOP(Universe::out_of_memory_error_metaspace()); 3697 } 3698 } 3699 3700 const char* Metaspace::metadata_type_name(Metaspace::MetadataType mdtype) { 3701 switch (mdtype) { 3702 case Metaspace::ClassType: return "Class"; 3703 case Metaspace::NonClassType: return "Metadata"; 3704 default: 3705 assert(false, "Got bad mdtype: %d", (int) mdtype); 3706 return NULL; 3707 } 3708 } 3709 3710 void Metaspace::record_allocation(void* ptr, MetaspaceObj::Type type, size_t word_size) { 3711 assert(DumpSharedSpaces, "sanity"); 3712 3713 int byte_size = (int)word_size * wordSize; 3714 AllocRecord *rec = new AllocRecord((address)ptr, type, byte_size); 3715 3716 if (_alloc_record_head == NULL) { 3717 _alloc_record_head = _alloc_record_tail = rec; 3718 } else if (_alloc_record_tail->_ptr + _alloc_record_tail->_byte_size == (address)ptr) { 3719 _alloc_record_tail->_next = rec; 3720 _alloc_record_tail = rec; 3721 } else { 3722 // slow linear search, but this doesn't happen that often, and only when dumping 3723 for (AllocRecord *old = _alloc_record_head; old; old = old->_next) { 3724 if (old->_ptr == ptr) { 3725 assert(old->_type == MetaspaceObj::DeallocatedType, "sanity"); 3726 int remain_bytes = old->_byte_size - byte_size; 3727 assert(remain_bytes >= 0, "sanity"); 3728 old->_type = type; 3729 3730 if (remain_bytes == 0) { 3731 delete(rec); 3732 } else { 3733 address remain_ptr = address(ptr) + byte_size; 3734 rec->_ptr = remain_ptr; 3735 rec->_byte_size = remain_bytes; 3736 rec->_type = MetaspaceObj::DeallocatedType; 3737 rec->_next = old->_next; 3738 old->_byte_size = byte_size; 3739 old->_next = rec; 3740 } 3741 return; 3742 } 3743 } 3744 assert(0, "reallocating a freed pointer that was not recorded"); 3745 } 3746 } 3747 3748 void Metaspace::record_deallocation(void* ptr, size_t word_size) { 3749 assert(DumpSharedSpaces, "sanity"); 3750 3751 for (AllocRecord *rec = _alloc_record_head; rec; rec = rec->_next) { 3752 if (rec->_ptr == ptr) { 3753 assert(rec->_byte_size == (int)word_size * wordSize, "sanity"); 3754 rec->_type = MetaspaceObj::DeallocatedType; 3755 return; 3756 } 3757 } 3758 3759 assert(0, "deallocating a pointer that was not recorded"); 3760 } 3761 3762 void Metaspace::iterate(Metaspace::AllocRecordClosure *closure) { 3763 assert(DumpSharedSpaces, "unimplemented for !DumpSharedSpaces"); 3764 3765 address last_addr = (address)bottom(); 3766 3767 for (AllocRecord *rec = _alloc_record_head; rec; rec = rec->_next) { 3768 address ptr = rec->_ptr; 3769 if (last_addr < ptr) { 3770 closure->doit(last_addr, MetaspaceObj::UnknownType, ptr - last_addr); 3771 } 3772 closure->doit(ptr, rec->_type, rec->_byte_size); 3773 last_addr = ptr + rec->_byte_size; 3774 } 3775 3776 address top = ((address)bottom()) + used_bytes_slow(Metaspace::NonClassType); 3777 if (last_addr < top) { 3778 closure->doit(last_addr, MetaspaceObj::UnknownType, top - last_addr); 3779 } 3780 } 3781 3782 void Metaspace::purge(MetadataType mdtype) { 3783 get_space_list(mdtype)->purge(get_chunk_manager(mdtype)); 3784 } 3785 3786 void Metaspace::purge() { 3787 MutexLockerEx cl(SpaceManager::expand_lock(), 3788 Mutex::_no_safepoint_check_flag); 3789 purge(NonClassType); 3790 if (using_class_space()) { 3791 purge(ClassType); 3792 } 3793 } 3794 3795 void Metaspace::print_on(outputStream* out) const { 3796 // Print both class virtual space counts and metaspace. 3797 if (Verbose) { 3798 vsm()->print_on(out); 3799 if (using_class_space()) { 3800 class_vsm()->print_on(out); 3801 } 3802 } 3803 } 3804 3805 bool Metaspace::contains(const void* ptr) { 3806 if (UseSharedSpaces && MetaspaceShared::is_in_shared_space(ptr)) { 3807 return true; 3808 } 3809 return contains_non_shared(ptr); 3810 } 3811 3812 bool Metaspace::contains_non_shared(const void* ptr) { 3813 if (using_class_space() && get_space_list(ClassType)->contains(ptr)) { 3814 return true; 3815 } 3816 3817 return get_space_list(NonClassType)->contains(ptr); 3818 } 3819 3820 void Metaspace::verify() { 3821 vsm()->verify(); 3822 if (using_class_space()) { 3823 class_vsm()->verify(); 3824 } 3825 } 3826 3827 void Metaspace::dump(outputStream* const out) const { 3828 out->print_cr("\nVirtual space manager: " INTPTR_FORMAT, p2i(vsm())); 3829 vsm()->dump(out); 3830 if (using_class_space()) { 3831 out->print_cr("\nClass space manager: " INTPTR_FORMAT, p2i(class_vsm())); 3832 class_vsm()->dump(out); 3833 } 3834 } 3835 3836 /////////////// Unit tests /////////////// 3837 3838 #ifndef PRODUCT 3839 3840 class TestMetaspaceAuxTest : AllStatic { 3841 public: 3842 static void test_reserved() { 3843 size_t reserved = MetaspaceAux::reserved_bytes(); 3844 3845 assert(reserved > 0, "assert"); 3846 3847 size_t committed = MetaspaceAux::committed_bytes(); 3848 assert(committed <= reserved, "assert"); 3849 3850 size_t reserved_metadata = MetaspaceAux::reserved_bytes(Metaspace::NonClassType); 3851 assert(reserved_metadata > 0, "assert"); 3852 assert(reserved_metadata <= reserved, "assert"); 3853 3854 if (UseCompressedClassPointers) { 3855 size_t reserved_class = MetaspaceAux::reserved_bytes(Metaspace::ClassType); 3856 assert(reserved_class > 0, "assert"); 3857 assert(reserved_class < reserved, "assert"); 3858 } 3859 } 3860 3861 static void test_committed() { 3862 size_t committed = MetaspaceAux::committed_bytes(); 3863 3864 assert(committed > 0, "assert"); 3865 3866 size_t reserved = MetaspaceAux::reserved_bytes(); 3867 assert(committed <= reserved, "assert"); 3868 3869 size_t committed_metadata = MetaspaceAux::committed_bytes(Metaspace::NonClassType); 3870 assert(committed_metadata > 0, "assert"); 3871 assert(committed_metadata <= committed, "assert"); 3872 3873 if (UseCompressedClassPointers) { 3874 size_t committed_class = MetaspaceAux::committed_bytes(Metaspace::ClassType); 3875 assert(committed_class > 0, "assert"); 3876 assert(committed_class < committed, "assert"); 3877 } 3878 } 3879 3880 static void test_virtual_space_list_large_chunk() { 3881 VirtualSpaceList* vs_list = new VirtualSpaceList(os::vm_allocation_granularity()); 3882 MutexLockerEx cl(SpaceManager::expand_lock(), Mutex::_no_safepoint_check_flag); 3883 // A size larger than VirtualSpaceSize (256k) and add one page to make it _not_ be 3884 // vm_allocation_granularity aligned on Windows. 3885 size_t large_size = (size_t)(2*256*K + (os::vm_page_size()/BytesPerWord)); 3886 large_size += (os::vm_page_size()/BytesPerWord); 3887 vs_list->get_new_chunk(large_size, 0); 3888 } 3889 3890 static void test() { 3891 test_reserved(); 3892 test_committed(); 3893 test_virtual_space_list_large_chunk(); 3894 } 3895 }; 3896 3897 void TestMetaspaceAux_test() { 3898 TestMetaspaceAuxTest::test(); 3899 } 3900 3901 class TestVirtualSpaceNodeTest { 3902 static void chunk_up(size_t words_left, size_t& num_medium_chunks, 3903 size_t& num_small_chunks, 3904 size_t& num_specialized_chunks) { 3905 num_medium_chunks = words_left / MediumChunk; 3906 words_left = words_left % MediumChunk; 3907 3908 num_small_chunks = words_left / SmallChunk; 3909 words_left = words_left % SmallChunk; 3910 // how many specialized chunks can we get? 3911 num_specialized_chunks = words_left / SpecializedChunk; 3912 assert(words_left % SpecializedChunk == 0, "should be nothing left"); 3913 } 3914 3915 public: 3916 static void test() { 3917 MutexLockerEx ml(SpaceManager::expand_lock(), Mutex::_no_safepoint_check_flag); 3918 const size_t vsn_test_size_words = MediumChunk * 4; 3919 const size_t vsn_test_size_bytes = vsn_test_size_words * BytesPerWord; 3920 3921 // The chunk sizes must be multiples of eachother, or this will fail 3922 STATIC_ASSERT(MediumChunk % SmallChunk == 0); 3923 STATIC_ASSERT(SmallChunk % SpecializedChunk == 0); 3924 3925 { // No committed memory in VSN 3926 ChunkManager cm(SpecializedChunk, SmallChunk, MediumChunk); 3927 VirtualSpaceNode vsn(vsn_test_size_bytes); 3928 vsn.initialize(); 3929 vsn.retire(&cm); 3930 assert(cm.sum_free_chunks_count() == 0, "did not commit any memory in the VSN"); 3931 } 3932 3933 { // All of VSN is committed, half is used by chunks 3934 ChunkManager cm(SpecializedChunk, SmallChunk, MediumChunk); 3935 VirtualSpaceNode vsn(vsn_test_size_bytes); 3936 vsn.initialize(); 3937 vsn.expand_by(vsn_test_size_words, vsn_test_size_words); 3938 vsn.get_chunk_vs(MediumChunk); 3939 vsn.get_chunk_vs(MediumChunk); 3940 vsn.retire(&cm); 3941 assert(cm.sum_free_chunks_count() == 2, "should have been memory left for 2 medium chunks"); 3942 assert(cm.sum_free_chunks() == 2*MediumChunk, "sizes should add up"); 3943 } 3944 3945 const size_t page_chunks = 4 * (size_t)os::vm_page_size() / BytesPerWord; 3946 // This doesn't work for systems with vm_page_size >= 16K. 3947 if (page_chunks < MediumChunk) { 3948 // 4 pages of VSN is committed, some is used by chunks 3949 ChunkManager cm(SpecializedChunk, SmallChunk, MediumChunk); 3950 VirtualSpaceNode vsn(vsn_test_size_bytes); 3951 3952 vsn.initialize(); 3953 vsn.expand_by(page_chunks, page_chunks); 3954 vsn.get_chunk_vs(SmallChunk); 3955 vsn.get_chunk_vs(SpecializedChunk); 3956 vsn.retire(&cm); 3957 3958 // committed - used = words left to retire 3959 const size_t words_left = page_chunks - SmallChunk - SpecializedChunk; 3960 3961 size_t num_medium_chunks, num_small_chunks, num_spec_chunks; 3962 chunk_up(words_left, num_medium_chunks, num_small_chunks, num_spec_chunks); 3963 3964 assert(num_medium_chunks == 0, "should not get any medium chunks"); 3965 assert(cm.sum_free_chunks_count() == (num_small_chunks + num_spec_chunks), "should be space for 3 chunks"); 3966 assert(cm.sum_free_chunks() == words_left, "sizes should add up"); 3967 } 3968 3969 { // Half of VSN is committed, a humongous chunk is used 3970 ChunkManager cm(SpecializedChunk, SmallChunk, MediumChunk); 3971 VirtualSpaceNode vsn(vsn_test_size_bytes); 3972 vsn.initialize(); 3973 vsn.expand_by(MediumChunk * 2, MediumChunk * 2); 3974 vsn.get_chunk_vs(MediumChunk + SpecializedChunk); // Humongous chunks will be aligned up to MediumChunk + SpecializedChunk 3975 vsn.retire(&cm); 3976 3977 const size_t words_left = MediumChunk * 2 - (MediumChunk + SpecializedChunk); 3978 size_t num_medium_chunks, num_small_chunks, num_spec_chunks; 3979 chunk_up(words_left, num_medium_chunks, num_small_chunks, num_spec_chunks); 3980 3981 assert(num_medium_chunks == 0, "should not get any medium chunks"); 3982 assert(cm.sum_free_chunks_count() == (num_small_chunks + num_spec_chunks), "should be space for 3 chunks"); 3983 assert(cm.sum_free_chunks() == words_left, "sizes should add up"); 3984 } 3985 3986 } 3987 3988 #define assert_is_available_positive(word_size) \ 3989 assert(vsn.is_available(word_size), \ 3990 #word_size ": " PTR_FORMAT " bytes were not available in " \ 3991 "VirtualSpaceNode [" PTR_FORMAT ", " PTR_FORMAT ")", \ 3992 (uintptr_t)(word_size * BytesPerWord), p2i(vsn.bottom()), p2i(vsn.end())); 3993 3994 #define assert_is_available_negative(word_size) \ 3995 assert(!vsn.is_available(word_size), \ 3996 #word_size ": " PTR_FORMAT " bytes should not be available in " \ 3997 "VirtualSpaceNode [" PTR_FORMAT ", " PTR_FORMAT ")", \ 3998 (uintptr_t)(word_size * BytesPerWord), p2i(vsn.bottom()), p2i(vsn.end())); 3999 4000 static void test_is_available_positive() { 4001 // Reserve some memory. 4002 VirtualSpaceNode vsn(os::vm_allocation_granularity()); 4003 assert(vsn.initialize(), "Failed to setup VirtualSpaceNode"); 4004 4005 // Commit some memory. 4006 size_t commit_word_size = os::vm_allocation_granularity() / BytesPerWord; 4007 bool expanded = vsn.expand_by(commit_word_size, commit_word_size); 4008 assert(expanded, "Failed to commit"); 4009 4010 // Check that is_available accepts the committed size. 4011 assert_is_available_positive(commit_word_size); 4012 4013 // Check that is_available accepts half the committed size. 4014 size_t expand_word_size = commit_word_size / 2; 4015 assert_is_available_positive(expand_word_size); 4016 } 4017 4018 static void test_is_available_negative() { 4019 // Reserve some memory. 4020 VirtualSpaceNode vsn(os::vm_allocation_granularity()); 4021 assert(vsn.initialize(), "Failed to setup VirtualSpaceNode"); 4022 4023 // Commit some memory. 4024 size_t commit_word_size = os::vm_allocation_granularity() / BytesPerWord; 4025 bool expanded = vsn.expand_by(commit_word_size, commit_word_size); 4026 assert(expanded, "Failed to commit"); 4027 4028 // Check that is_available doesn't accept a too large size. 4029 size_t two_times_commit_word_size = commit_word_size * 2; 4030 assert_is_available_negative(two_times_commit_word_size); 4031 } 4032 4033 static void test_is_available_overflow() { 4034 // Reserve some memory. 4035 VirtualSpaceNode vsn(os::vm_allocation_granularity()); 4036 assert(vsn.initialize(), "Failed to setup VirtualSpaceNode"); 4037 4038 // Commit some memory. 4039 size_t commit_word_size = os::vm_allocation_granularity() / BytesPerWord; 4040 bool expanded = vsn.expand_by(commit_word_size, commit_word_size); 4041 assert(expanded, "Failed to commit"); 4042 4043 // Calculate a size that will overflow the virtual space size. 4044 void* virtual_space_max = (void*)(uintptr_t)-1; 4045 size_t bottom_to_max = pointer_delta(virtual_space_max, vsn.bottom(), 1); 4046 size_t overflow_size = bottom_to_max + BytesPerWord; 4047 size_t overflow_word_size = overflow_size / BytesPerWord; 4048 4049 // Check that is_available can handle the overflow. 4050 assert_is_available_negative(overflow_word_size); 4051 } 4052 4053 static void test_is_available() { 4054 TestVirtualSpaceNodeTest::test_is_available_positive(); 4055 TestVirtualSpaceNodeTest::test_is_available_negative(); 4056 TestVirtualSpaceNodeTest::test_is_available_overflow(); 4057 } 4058 }; 4059 4060 void TestVirtualSpaceNode_test() { 4061 TestVirtualSpaceNodeTest::test(); 4062 TestVirtualSpaceNodeTest::test_is_available(); 4063 } 4064 4065 // The following test is placed here instead of a gtest / unittest file 4066 // because the ChunkManager class is only available in this file. 4067 void ChunkManager_test_list_index() { 4068 ChunkManager manager(ClassSpecializedChunk, ClassSmallChunk, ClassMediumChunk); 4069 4070 // Test previous bug where a query for a humongous class metachunk, 4071 // incorrectly matched the non-class medium metachunk size. 4072 { 4073 assert(MediumChunk > ClassMediumChunk, "Precondition for test"); 4074 4075 ChunkIndex index = manager.list_index(MediumChunk); 4076 4077 assert(index == HumongousIndex, 4078 "Requested size is larger than ClassMediumChunk," 4079 " so should return HumongousIndex. Got index: %d", (int)index); 4080 } 4081 4082 // Check the specified sizes as well. 4083 { 4084 ChunkIndex index = manager.list_index(ClassSpecializedChunk); 4085 assert(index == SpecializedIndex, "Wrong index returned. Got index: %d", (int)index); 4086 } 4087 { 4088 ChunkIndex index = manager.list_index(ClassSmallChunk); 4089 assert(index == SmallIndex, "Wrong index returned. Got index: %d", (int)index); 4090 } 4091 { 4092 ChunkIndex index = manager.list_index(ClassMediumChunk); 4093 assert(index == MediumIndex, "Wrong index returned. Got index: %d", (int)index); 4094 } 4095 { 4096 ChunkIndex index = manager.list_index(ClassMediumChunk + 1); 4097 assert(index == HumongousIndex, "Wrong index returned. Got index: %d", (int)index); 4098 } 4099 } 4100 4101 #endif // !PRODUCT 4102 4103 #ifdef ASSERT 4104 4105 // ChunkManagerReturnTest stresses taking/returning chunks from the ChunkManager. It takes and 4106 // returns chunks from/to the ChunkManager while keeping track of the expected ChunkManager 4107 // content. 4108 class ChunkManagerReturnTestImpl { 4109 4110 VirtualSpaceNode _vsn; 4111 ChunkManager _cm; 4112 4113 // The expected content of the chunk manager. 4114 unsigned _chunks_in_chunkmanager; 4115 size_t _words_in_chunkmanager; 4116 4117 // A fixed size pool of chunks. Chunks may be in the chunk manager (free) or not (in use). 4118 static const int num_chunks = 256; 4119 Metachunk* _pool[num_chunks]; 4120 4121 // Helper, return a random position into the chunk pool. 4122 static int get_random_position() { 4123 return os::random() % num_chunks; 4124 } 4125 4126 // Asserts that ChunkManager counters match expectations. 4127 void assert_counters() { 4128 assert(_vsn.container_count() == num_chunks - _chunks_in_chunkmanager, "vsn counter mismatch."); 4129 assert(_cm.free_chunks_count() == _chunks_in_chunkmanager, "cm counter mismatch."); 4130 assert(_cm.free_chunks_total_words() == _words_in_chunkmanager, "cm counter mismatch."); 4131 } 4132 4133 // Get a random chunk size. Equal chance to get spec/med/small chunk size or 4134 // a humongous chunk size. The latter itself is random in the range of [med+spec..4*med). 4135 size_t get_random_chunk_size() { 4136 const size_t sizes [] = { SpecializedChunk, SmallChunk, MediumChunk }; 4137 const int rand = os::random() % 4; 4138 if (rand < 3) { 4139 return sizes[rand]; 4140 } else { 4141 // Note: this affects the max. size of space (see _vsn initialization in ctor). 4142 return align_up(MediumChunk + 1 + (os::random() % (MediumChunk * 4)), SpecializedChunk); 4143 } 4144 } 4145 4146 // Starting at pool index <start>+1, find the next chunk tagged as either free or in use, depending 4147 // on <is_free>. Search wraps. Returns its position, or -1 if no matching chunk was found. 4148 int next_matching_chunk(int start, bool is_free) const { 4149 assert(start >= 0 && start < num_chunks, "invalid parameter"); 4150 int pos = start; 4151 do { 4152 if (++pos == num_chunks) { 4153 pos = 0; 4154 } 4155 if (_pool[pos]->is_tagged_free() == is_free) { 4156 return pos; 4157 } 4158 } while (pos != start); 4159 return -1; 4160 } 4161 4162 // A structure to keep information about a chunk list including which 4163 // chunks are part of this list. This is needed to keep information about a chunk list 4164 // we will to return to the ChunkManager, because the original list will be destroyed. 4165 struct AChunkList { 4166 Metachunk* head; 4167 Metachunk* all[num_chunks]; 4168 size_t size; 4169 int num; 4170 ChunkIndex index; 4171 }; 4172 4173 // Assemble, from the in-use chunks (not in the chunk manager) in the pool, 4174 // a random chunk list of max. length <list_size> of chunks with the same 4175 // ChunkIndex (chunk size). 4176 // Returns false if list cannot be assembled. List is returned in the <out> 4177 // structure. Returned list may be smaller than <list_size>. 4178 bool assemble_random_chunklist(AChunkList* out, int list_size) { 4179 // Choose a random in-use chunk from the pool... 4180 const int headpos = next_matching_chunk(get_random_position(), false); 4181 if (headpos == -1) { 4182 return false; 4183 } 4184 Metachunk* const head = _pool[headpos]; 4185 out->all[0] = head; 4186 assert(head->is_tagged_free() == false, "Chunk state mismatch"); 4187 // ..then go from there, chain it up with up to list_size - 1 number of other 4188 // in-use chunks of the same index. 4189 const ChunkIndex index = _cm.list_index(head->word_size()); 4190 int num_added = 1; 4191 size_t size_added = head->word_size(); 4192 int pos = headpos; 4193 Metachunk* tail = head; 4194 do { 4195 pos = next_matching_chunk(pos, false); 4196 if (pos != headpos) { 4197 Metachunk* c = _pool[pos]; 4198 assert(c->is_tagged_free() == false, "Chunk state mismatch"); 4199 if (index == _cm.list_index(c->word_size())) { 4200 tail->set_next(c); 4201 c->set_prev(tail); 4202 tail = c; 4203 out->all[num_added] = c; 4204 num_added ++; 4205 size_added += c->word_size(); 4206 } 4207 } 4208 } while (num_added < list_size && pos != headpos); 4209 out->head = head; 4210 out->index = index; 4211 out->size = size_added; 4212 out->num = num_added; 4213 return true; 4214 } 4215 4216 // Take a single random chunk from the ChunkManager. 4217 bool take_single_random_chunk_from_chunkmanager() { 4218 assert_counters(); 4219 _cm.locked_verify(); 4220 int pos = next_matching_chunk(get_random_position(), true); 4221 if (pos == -1) { 4222 return false; 4223 } 4224 Metachunk* c = _pool[pos]; 4225 assert(c->is_tagged_free(), "Chunk state mismatch"); 4226 // Note: instead of using ChunkManager::remove_chunk on this one chunk, we call 4227 // ChunkManager::free_chunks_get() with this chunk's word size. We really want 4228 // to exercise ChunkManager::free_chunks_get() because that one gets called for 4229 // normal chunk allocation. 4230 Metachunk* c2 = _cm.free_chunks_get(c->word_size()); 4231 assert(c2 != NULL, "Unexpected."); 4232 assert(!c2->is_tagged_free(), "Chunk state mismatch"); 4233 assert(c2->next() == NULL && c2->prev() == NULL, "Chunk should be outside of a list."); 4234 _chunks_in_chunkmanager --; 4235 _words_in_chunkmanager -= c->word_size(); 4236 assert_counters(); 4237 _cm.locked_verify(); 4238 return true; 4239 } 4240 4241 // Returns a single random chunk to the chunk manager. Returns false if that 4242 // was not possible (all chunks are already in the chunk manager). 4243 bool return_single_random_chunk_to_chunkmanager() { 4244 assert_counters(); 4245 _cm.locked_verify(); 4246 int pos = next_matching_chunk(get_random_position(), false); 4247 if (pos == -1) { 4248 return false; 4249 } 4250 Metachunk* c = _pool[pos]; 4251 assert(c->is_tagged_free() == false, "wrong chunk information"); 4252 _cm.return_single_chunk(_cm.list_index(c->word_size()), c); 4253 _chunks_in_chunkmanager ++; 4254 _words_in_chunkmanager += c->word_size(); 4255 assert(c->is_tagged_free() == true, "wrong chunk information"); 4256 assert_counters(); 4257 _cm.locked_verify(); 4258 return true; 4259 } 4260 4261 // Return a random chunk list to the chunk manager. Returns the length of the 4262 // returned list. 4263 int return_random_chunk_list_to_chunkmanager(int list_size) { 4264 assert_counters(); 4265 _cm.locked_verify(); 4266 AChunkList aChunkList; 4267 if (!assemble_random_chunklist(&aChunkList, list_size)) { 4268 return 0; 4269 } 4270 // Before returning chunks are returned, they should be tagged in use. 4271 for (int i = 0; i < aChunkList.num; i ++) { 4272 assert(!aChunkList.all[i]->is_tagged_free(), "chunk state mismatch."); 4273 } 4274 _cm.return_chunk_list(aChunkList.index, aChunkList.head); 4275 _chunks_in_chunkmanager += aChunkList.num; 4276 _words_in_chunkmanager += aChunkList.size; 4277 // After all chunks are returned, check that they are now tagged free. 4278 for (int i = 0; i < aChunkList.num; i ++) { 4279 assert(aChunkList.all[i]->is_tagged_free(), "chunk state mismatch."); 4280 } 4281 assert_counters(); 4282 _cm.locked_verify(); 4283 return aChunkList.num; 4284 } 4285 4286 public: 4287 4288 ChunkManagerReturnTestImpl() 4289 : _vsn(align_up(MediumChunk * num_chunks * 5 * sizeof(MetaWord), Metaspace::reserve_alignment())) 4290 , _cm(SpecializedChunk, SmallChunk, MediumChunk) 4291 , _chunks_in_chunkmanager(0) 4292 , _words_in_chunkmanager(0) 4293 { 4294 MutexLockerEx ml(SpaceManager::expand_lock(), Mutex::_no_safepoint_check_flag); 4295 // Allocate virtual space and allocate random chunks. Keep these chunks in the _pool. These chunks are 4296 // "in use", because not yet added to any chunk manager. 4297 _vsn.initialize(); 4298 _vsn.expand_by(_vsn.reserved_words(), _vsn.reserved_words()); 4299 for (int i = 0; i < num_chunks; i ++) { 4300 const size_t size = get_random_chunk_size(); 4301 _pool[i] = _vsn.get_chunk_vs(size); 4302 assert(_pool[i] != NULL, "allocation failed"); 4303 } 4304 assert_counters(); 4305 _cm.locked_verify(); 4306 } 4307 4308 // Test entry point. 4309 // Return some chunks to the chunk manager (return phase). Take some chunks out (take phase). Repeat. 4310 // Chunks are choosen randomly. Number of chunks to return or taken are choosen randomly, but affected 4311 // by the <phase_length_factor> argument: a factor of 0.0 will cause the test to quickly alternate between 4312 // returning and taking, whereas a factor of 1.0 will take/return all chunks from/to the 4313 // chunks manager, thereby emptying or filling it completely. 4314 void do_test(float phase_length_factor) { 4315 MutexLockerEx ml(SpaceManager::expand_lock(), Mutex::_no_safepoint_check_flag); 4316 assert_counters(); 4317 // Execute n operations, and operation being the move of a single chunk to/from the chunk manager. 4318 const int num_max_ops = num_chunks * 100; 4319 int num_ops = num_max_ops; 4320 const int average_phase_length = (int)(phase_length_factor * num_chunks); 4321 int num_ops_until_switch = MAX2(1, (average_phase_length + os::random() % 8 - 4)); 4322 bool return_phase = true; 4323 while (num_ops > 0) { 4324 int chunks_moved = 0; 4325 if (return_phase) { 4326 // Randomly switch between returning a single chunk or a random length chunk list. 4327 if (os::random() % 2 == 0) { 4328 if (return_single_random_chunk_to_chunkmanager()) { 4329 chunks_moved = 1; 4330 } 4331 } else { 4332 const int list_length = MAX2(1, (os::random() % num_ops_until_switch)); 4333 chunks_moved = return_random_chunk_list_to_chunkmanager(list_length); 4334 } 4335 } else { 4336 // Breath out. 4337 if (take_single_random_chunk_from_chunkmanager()) { 4338 chunks_moved = 1; 4339 } 4340 } 4341 num_ops -= chunks_moved; 4342 num_ops_until_switch -= chunks_moved; 4343 if (chunks_moved == 0 || num_ops_until_switch <= 0) { 4344 return_phase = !return_phase; 4345 num_ops_until_switch = MAX2(1, (average_phase_length + os::random() % 8 - 4)); 4346 } 4347 } 4348 } 4349 }; 4350 4351 void* setup_chunkmanager_returntests() { 4352 ChunkManagerReturnTestImpl* p = new ChunkManagerReturnTestImpl(); 4353 return p; 4354 } 4355 4356 void teardown_chunkmanager_returntests(void* p) { 4357 delete (ChunkManagerReturnTestImpl*) p; 4358 } 4359 4360 void run_chunkmanager_returntests(void* p, float phase_length) { 4361 ChunkManagerReturnTestImpl* test = (ChunkManagerReturnTestImpl*) p; 4362 test->do_test(phase_length); 4363 } 4364 4365 // The following test is placed here instead of a gtest / unittest file 4366 // because the ChunkManager class is only available in this file. 4367 class SpaceManagerTest : AllStatic { 4368 friend void SpaceManager_test_adjust_initial_chunk_size(); 4369 4370 static void test_adjust_initial_chunk_size(bool is_class) { 4371 const size_t smallest = SpaceManager::smallest_chunk_size(is_class); 4372 const size_t normal = SpaceManager::small_chunk_size(is_class); 4373 const size_t medium = SpaceManager::medium_chunk_size(is_class); 4374 4375 #define test_adjust_initial_chunk_size(value, expected, is_class_value) \ 4376 do { \ 4377 size_t v = value; \ 4378 size_t e = expected; \ 4379 assert(SpaceManager::adjust_initial_chunk_size(v, (is_class_value)) == e, \ 4380 "Expected: " SIZE_FORMAT " got: " SIZE_FORMAT, e, v); \ 4381 } while (0) 4382 4383 // Smallest (specialized) 4384 test_adjust_initial_chunk_size(1, smallest, is_class); 4385 test_adjust_initial_chunk_size(smallest - 1, smallest, is_class); 4386 test_adjust_initial_chunk_size(smallest, smallest, is_class); 4387 4388 // Small 4389 test_adjust_initial_chunk_size(smallest + 1, normal, is_class); 4390 test_adjust_initial_chunk_size(normal - 1, normal, is_class); 4391 test_adjust_initial_chunk_size(normal, normal, is_class); 4392 4393 // Medium 4394 test_adjust_initial_chunk_size(normal + 1, medium, is_class); 4395 test_adjust_initial_chunk_size(medium - 1, medium, is_class); 4396 test_adjust_initial_chunk_size(medium, medium, is_class); 4397 4398 // Humongous 4399 test_adjust_initial_chunk_size(medium + 1, medium + 1, is_class); 4400 4401 #undef test_adjust_initial_chunk_size 4402 } 4403 4404 static void test_adjust_initial_chunk_size() { 4405 test_adjust_initial_chunk_size(false); 4406 test_adjust_initial_chunk_size(true); 4407 } 4408 }; 4409 4410 void SpaceManager_test_adjust_initial_chunk_size() { 4411 SpaceManagerTest::test_adjust_initial_chunk_size(); 4412 } 4413 4414 #endif // ASSERT