1 /* 2 * Copyright (c) 2011, 2017, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. 8 * 9 * This code is distributed in the hope that it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 12 * version 2 for more details (a copy is included in the LICENSE file that 13 * accompanied this code). 14 * 15 * You should have received a copy of the GNU General Public License version 16 * 2 along with this work; if not, write to the Free Software Foundation, 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 18 * 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 20 * or visit www.oracle.com if you need additional information or have any 21 * questions. 22 * 23 */ 24 #include "precompiled.hpp" 25 #include "aot/aotLoader.hpp" 26 #include "gc/shared/collectedHeap.hpp" 27 #include "gc/shared/collectorPolicy.hpp" 28 #include "gc/shared/gcLocker.hpp" 29 #include "logging/log.hpp" 30 #include "memory/allocation.hpp" 31 #include "memory/binaryTreeDictionary.hpp" 32 #include "memory/filemap.hpp" 33 #include "memory/freeList.hpp" 34 #include "memory/metachunk.hpp" 35 #include "memory/metaspace.hpp" 36 #include "memory/metaspaceGCThresholdUpdater.hpp" 37 #include "memory/metaspaceShared.hpp" 38 #include "memory/metaspaceTracer.hpp" 39 #include "memory/resourceArea.hpp" 40 #include "memory/universe.hpp" 41 #include "runtime/atomic.hpp" 42 #include "runtime/globals.hpp" 43 #include "runtime/init.hpp" 44 #include "runtime/java.hpp" 45 #include "runtime/mutex.hpp" 46 #include "runtime/orderAccess.inline.hpp" 47 #include "services/memTracker.hpp" 48 #include "services/memoryService.hpp" 49 #include "utilities/copy.hpp" 50 #include "utilities/debug.hpp" 51 #include "utilities/macros.hpp" 52 53 typedef BinaryTreeDictionary<Metablock, FreeList<Metablock> > BlockTreeDictionary; 54 typedef BinaryTreeDictionary<Metachunk, FreeList<Metachunk> > ChunkTreeDictionary; 55 56 // Set this constant to enable slow integrity checking of the free chunk lists 57 const bool metaspace_slow_verify = false; 58 59 size_t const allocation_from_dictionary_limit = 4 * K; 60 61 MetaWord* last_allocated = 0; 62 63 size_t Metaspace::_compressed_class_space_size; 64 const MetaspaceTracer* Metaspace::_tracer = NULL; 65 66 // Used in declarations in SpaceManager and ChunkManager 67 enum ChunkIndex { 68 ZeroIndex = 0, 69 SpecializedIndex = ZeroIndex, 70 SmallIndex = SpecializedIndex + 1, 71 MediumIndex = SmallIndex + 1, 72 HumongousIndex = MediumIndex + 1, 73 NumberOfFreeLists = 3, 74 NumberOfInUseLists = 4 75 }; 76 77 // Helper, returns a descriptive name for the given index. 78 static const char* chunk_size_name(ChunkIndex index) { 79 switch (index) { 80 case SpecializedIndex: 81 return "specialized"; 82 case SmallIndex: 83 return "small"; 84 case MediumIndex: 85 return "medium"; 86 case HumongousIndex: 87 return "humongous"; 88 default: 89 return "Invalid index"; 90 } 91 } 92 93 enum ChunkSizes { // in words. 94 ClassSpecializedChunk = 128, 95 SpecializedChunk = 128, 96 ClassSmallChunk = 256, 97 SmallChunk = 512, 98 ClassMediumChunk = 4 * K, 99 MediumChunk = 8 * K 100 }; 101 102 static ChunkIndex next_chunk_index(ChunkIndex i) { 103 assert(i < NumberOfInUseLists, "Out of bound"); 104 return (ChunkIndex) (i+1); 105 } 106 107 volatile intptr_t MetaspaceGC::_capacity_until_GC = 0; 108 uint MetaspaceGC::_shrink_factor = 0; 109 bool MetaspaceGC::_should_concurrent_collect = false; 110 111 typedef class FreeList<Metachunk> ChunkList; 112 113 // Manages the global free lists of chunks. 114 class ChunkManager : public CHeapObj<mtInternal> { 115 friend class TestVirtualSpaceNodeTest; 116 117 // Free list of chunks of different sizes. 118 // SpecializedChunk 119 // SmallChunk 120 // MediumChunk 121 ChunkList _free_chunks[NumberOfFreeLists]; 122 123 // Return non-humongous chunk list by its index. 124 ChunkList* free_chunks(ChunkIndex index); 125 126 // Returns non-humongous chunk list for the given chunk word size. 127 ChunkList* find_free_chunks_list(size_t word_size); 128 129 // HumongousChunk 130 ChunkTreeDictionary _humongous_dictionary; 131 132 // Returns the humongous chunk dictionary. 133 ChunkTreeDictionary* humongous_dictionary() { 134 return &_humongous_dictionary; 135 } 136 137 // Size, in metaspace words, of all chunks managed by this ChunkManager 138 size_t _free_chunks_total; 139 // Number of chunks in this ChunkManager 140 size_t _free_chunks_count; 141 142 // Update counters after a chunk was added or removed removed. 143 void account_for_added_chunk(const Metachunk* c); 144 void account_for_removed_chunk(const Metachunk* c); 145 146 // Debug support 147 148 size_t sum_free_chunks(); 149 size_t sum_free_chunks_count(); 150 151 void locked_verify_free_chunks_total(); 152 void slow_locked_verify_free_chunks_total() { 153 if (metaspace_slow_verify) { 154 locked_verify_free_chunks_total(); 155 } 156 } 157 void locked_verify_free_chunks_count(); 158 void slow_locked_verify_free_chunks_count() { 159 if (metaspace_slow_verify) { 160 locked_verify_free_chunks_count(); 161 } 162 } 163 void verify_free_chunks_count(); 164 165 public: 166 167 ChunkManager(size_t specialized_size, size_t small_size, size_t medium_size) 168 : _free_chunks_total(0), _free_chunks_count(0) { 169 _free_chunks[SpecializedIndex].set_size(specialized_size); 170 _free_chunks[SmallIndex].set_size(small_size); 171 _free_chunks[MediumIndex].set_size(medium_size); 172 } 173 174 // add or delete (return) a chunk to the global freelist. 175 Metachunk* chunk_freelist_allocate(size_t word_size); 176 177 // Map a size to a list index assuming that there are lists 178 // for special, small, medium, and humongous chunks. 179 ChunkIndex list_index(size_t size); 180 181 // Map a given index to the chunk size. 182 size_t size_by_index(ChunkIndex index); 183 184 // Take a chunk from the ChunkManager. The chunk is expected to be in 185 // the chunk manager (the freelist if non-humongous, the dictionary if 186 // humongous). 187 void remove_chunk(Metachunk* chunk); 188 189 // Return a single chunk of type index to the ChunkManager. 190 void return_single_chunk(ChunkIndex index, Metachunk* chunk); 191 192 // Add the simple linked list of chunks to the freelist of chunks 193 // of type index. 194 void return_chunk_list(ChunkIndex index, Metachunk* chunk); 195 196 // Total of the space in the free chunks list 197 size_t free_chunks_total_words(); 198 size_t free_chunks_total_bytes(); 199 200 // Number of chunks in the free chunks list 201 size_t free_chunks_count(); 202 203 // Remove from a list by size. Selects list based on size of chunk. 204 Metachunk* free_chunks_get(size_t chunk_word_size); 205 206 #define index_bounds_check(index) \ 207 assert(index == SpecializedIndex || \ 208 index == SmallIndex || \ 209 index == MediumIndex || \ 210 index == HumongousIndex, "Bad index: %d", (int) index) 211 212 size_t num_free_chunks(ChunkIndex index) const { 213 index_bounds_check(index); 214 215 if (index == HumongousIndex) { 216 return _humongous_dictionary.total_free_blocks(); 217 } 218 219 ssize_t count = _free_chunks[index].count(); 220 return count == -1 ? 0 : (size_t) count; 221 } 222 223 size_t size_free_chunks_in_bytes(ChunkIndex index) const { 224 index_bounds_check(index); 225 226 size_t word_size = 0; 227 if (index == HumongousIndex) { 228 word_size = _humongous_dictionary.total_size(); 229 } else { 230 const size_t size_per_chunk_in_words = _free_chunks[index].size(); 231 word_size = size_per_chunk_in_words * num_free_chunks(index); 232 } 233 234 return word_size * BytesPerWord; 235 } 236 237 MetaspaceChunkFreeListSummary chunk_free_list_summary() const { 238 return MetaspaceChunkFreeListSummary(num_free_chunks(SpecializedIndex), 239 num_free_chunks(SmallIndex), 240 num_free_chunks(MediumIndex), 241 num_free_chunks(HumongousIndex), 242 size_free_chunks_in_bytes(SpecializedIndex), 243 size_free_chunks_in_bytes(SmallIndex), 244 size_free_chunks_in_bytes(MediumIndex), 245 size_free_chunks_in_bytes(HumongousIndex)); 246 } 247 248 // Debug support 249 void verify(); 250 void slow_verify() { 251 if (metaspace_slow_verify) { 252 verify(); 253 } 254 } 255 void locked_verify(); 256 void slow_locked_verify() { 257 if (metaspace_slow_verify) { 258 locked_verify(); 259 } 260 } 261 void verify_free_chunks_total(); 262 263 void locked_print_free_chunks(outputStream* st); 264 void locked_print_sum_free_chunks(outputStream* st); 265 266 void print_on(outputStream* st) const; 267 }; 268 269 class SmallBlocks : public CHeapObj<mtClass> { 270 const static uint _small_block_max_size = sizeof(TreeChunk<Metablock, FreeList<Metablock> >)/HeapWordSize; 271 const static uint _small_block_min_size = sizeof(Metablock)/HeapWordSize; 272 273 private: 274 FreeList<Metablock> _small_lists[_small_block_max_size - _small_block_min_size]; 275 276 FreeList<Metablock>& list_at(size_t word_size) { 277 assert(word_size >= _small_block_min_size, "There are no metaspace objects less than %u words", _small_block_min_size); 278 return _small_lists[word_size - _small_block_min_size]; 279 } 280 281 public: 282 SmallBlocks() { 283 for (uint i = _small_block_min_size; i < _small_block_max_size; i++) { 284 uint k = i - _small_block_min_size; 285 _small_lists[k].set_size(i); 286 } 287 } 288 289 size_t total_size() const { 290 size_t result = 0; 291 for (uint i = _small_block_min_size; i < _small_block_max_size; i++) { 292 uint k = i - _small_block_min_size; 293 result = result + _small_lists[k].count() * _small_lists[k].size(); 294 } 295 return result; 296 } 297 298 static uint small_block_max_size() { return _small_block_max_size; } 299 static uint small_block_min_size() { return _small_block_min_size; } 300 301 MetaWord* get_block(size_t word_size) { 302 if (list_at(word_size).count() > 0) { 303 MetaWord* new_block = (MetaWord*) list_at(word_size).get_chunk_at_head(); 304 return new_block; 305 } else { 306 return NULL; 307 } 308 } 309 void return_block(Metablock* free_chunk, size_t word_size) { 310 list_at(word_size).return_chunk_at_head(free_chunk, false); 311 assert(list_at(word_size).count() > 0, "Should have a chunk"); 312 } 313 314 void print_on(outputStream* st) const { 315 st->print_cr("SmallBlocks:"); 316 for (uint i = _small_block_min_size; i < _small_block_max_size; i++) { 317 uint k = i - _small_block_min_size; 318 st->print_cr("small_lists size " SIZE_FORMAT " count " SIZE_FORMAT, _small_lists[k].size(), _small_lists[k].count()); 319 } 320 } 321 }; 322 323 // Used to manage the free list of Metablocks (a block corresponds 324 // to the allocation of a quantum of metadata). 325 class BlockFreelist : public CHeapObj<mtClass> { 326 BlockTreeDictionary* const _dictionary; 327 SmallBlocks* _small_blocks; 328 329 // Only allocate and split from freelist if the size of the allocation 330 // is at least 1/4th the size of the available block. 331 const static int WasteMultiplier = 4; 332 333 // Accessors 334 BlockTreeDictionary* dictionary() const { return _dictionary; } 335 SmallBlocks* small_blocks() { 336 if (_small_blocks == NULL) { 337 _small_blocks = new SmallBlocks(); 338 } 339 return _small_blocks; 340 } 341 342 public: 343 BlockFreelist(); 344 ~BlockFreelist(); 345 346 // Get and return a block to the free list 347 MetaWord* get_block(size_t word_size); 348 void return_block(MetaWord* p, size_t word_size); 349 350 size_t total_size() const { 351 size_t result = dictionary()->total_size(); 352 if (_small_blocks != NULL) { 353 result = result + _small_blocks->total_size(); 354 } 355 return result; 356 } 357 358 static size_t min_dictionary_size() { return TreeChunk<Metablock, FreeList<Metablock> >::min_size(); } 359 void print_on(outputStream* st) const; 360 }; 361 362 // A VirtualSpaceList node. 363 class VirtualSpaceNode : public CHeapObj<mtClass> { 364 friend class VirtualSpaceList; 365 366 // Link to next VirtualSpaceNode 367 VirtualSpaceNode* _next; 368 369 // total in the VirtualSpace 370 MemRegion _reserved; 371 ReservedSpace _rs; 372 VirtualSpace _virtual_space; 373 MetaWord* _top; 374 // count of chunks contained in this VirtualSpace 375 uintx _container_count; 376 377 // Convenience functions to access the _virtual_space 378 char* low() const { return virtual_space()->low(); } 379 char* high() const { return virtual_space()->high(); } 380 381 // The first Metachunk will be allocated at the bottom of the 382 // VirtualSpace 383 Metachunk* first_chunk() { return (Metachunk*) bottom(); } 384 385 // Committed but unused space in the virtual space 386 size_t free_words_in_vs() const; 387 public: 388 389 VirtualSpaceNode(size_t byte_size); 390 VirtualSpaceNode(ReservedSpace rs) : _top(NULL), _next(NULL), _rs(rs), _container_count(0) {} 391 ~VirtualSpaceNode(); 392 393 // Convenience functions for logical bottom and end 394 MetaWord* bottom() const { return (MetaWord*) _virtual_space.low(); } 395 MetaWord* end() const { return (MetaWord*) _virtual_space.high(); } 396 397 bool contains(const void* ptr) { return ptr >= low() && ptr < high(); } 398 399 size_t reserved_words() const { return _virtual_space.reserved_size() / BytesPerWord; } 400 size_t committed_words() const { return _virtual_space.actual_committed_size() / BytesPerWord; } 401 402 bool is_pre_committed() const { return _virtual_space.special(); } 403 404 // address of next available space in _virtual_space; 405 // Accessors 406 VirtualSpaceNode* next() { return _next; } 407 void set_next(VirtualSpaceNode* v) { _next = v; } 408 409 void set_reserved(MemRegion const v) { _reserved = v; } 410 void set_top(MetaWord* v) { _top = v; } 411 412 // Accessors 413 MemRegion* reserved() { return &_reserved; } 414 VirtualSpace* virtual_space() const { return (VirtualSpace*) &_virtual_space; } 415 416 // Returns true if "word_size" is available in the VirtualSpace 417 bool is_available(size_t word_size) { return word_size <= pointer_delta(end(), _top, sizeof(MetaWord)); } 418 419 MetaWord* top() const { return _top; } 420 void inc_top(size_t word_size) { _top += word_size; } 421 422 uintx container_count() { return _container_count; } 423 void inc_container_count(); 424 void dec_container_count(); 425 #ifdef ASSERT 426 uintx container_count_slow(); 427 void verify_container_count(); 428 #endif 429 430 // used and capacity in this single entry in the list 431 size_t used_words_in_vs() const; 432 size_t capacity_words_in_vs() const; 433 434 bool initialize(); 435 436 // get space from the virtual space 437 Metachunk* take_from_committed(size_t chunk_word_size); 438 439 // Allocate a chunk from the virtual space and return it. 440 Metachunk* get_chunk_vs(size_t chunk_word_size); 441 442 // Expands/shrinks the committed space in a virtual space. Delegates 443 // to Virtualspace 444 bool expand_by(size_t min_words, size_t preferred_words); 445 446 // In preparation for deleting this node, remove all the chunks 447 // in the node from any freelist. 448 void purge(ChunkManager* chunk_manager); 449 450 // If an allocation doesn't fit in the current node a new node is created. 451 // Allocate chunks out of the remaining committed space in this node 452 // to avoid wasting that memory. 453 // This always adds up because all the chunk sizes are multiples of 454 // the smallest chunk size. 455 void retire(ChunkManager* chunk_manager); 456 457 #ifdef ASSERT 458 // Debug support 459 void mangle(); 460 #endif 461 462 void print_on(outputStream* st) const; 463 }; 464 465 #define assert_is_ptr_aligned(ptr, alignment) \ 466 assert(is_ptr_aligned(ptr, alignment), \ 467 PTR_FORMAT " is not aligned to " \ 468 SIZE_FORMAT, p2i(ptr), alignment) 469 470 #define assert_is_size_aligned(size, alignment) \ 471 assert(is_size_aligned(size, alignment), \ 472 SIZE_FORMAT " is not aligned to " \ 473 SIZE_FORMAT, size, alignment) 474 475 476 // Decide if large pages should be committed when the memory is reserved. 477 static bool should_commit_large_pages_when_reserving(size_t bytes) { 478 if (UseLargePages && UseLargePagesInMetaspace && !os::can_commit_large_page_memory()) { 479 size_t words = bytes / BytesPerWord; 480 bool is_class = false; // We never reserve large pages for the class space. 481 if (MetaspaceGC::can_expand(words, is_class) && 482 MetaspaceGC::allowed_expansion() >= words) { 483 return true; 484 } 485 } 486 487 return false; 488 } 489 490 // byte_size is the size of the associated virtualspace. 491 VirtualSpaceNode::VirtualSpaceNode(size_t bytes) : _top(NULL), _next(NULL), _rs(), _container_count(0) { 492 assert_is_size_aligned(bytes, Metaspace::reserve_alignment()); 493 494 #if INCLUDE_CDS 495 // This allocates memory with mmap. For DumpSharedspaces, try to reserve 496 // configurable address, generally at the top of the Java heap so other 497 // memory addresses don't conflict. 498 if (DumpSharedSpaces) { 499 bool large_pages = false; // No large pages when dumping the CDS archive. 500 char* shared_base = (char*)align_ptr_up((char*)SharedBaseAddress, Metaspace::reserve_alignment()); 501 502 _rs = ReservedSpace(bytes, Metaspace::reserve_alignment(), large_pages, shared_base); 503 if (_rs.is_reserved()) { 504 assert(shared_base == 0 || _rs.base() == shared_base, "should match"); 505 } else { 506 // Get a mmap region anywhere if the SharedBaseAddress fails. 507 _rs = ReservedSpace(bytes, Metaspace::reserve_alignment(), large_pages); 508 } 509 if (!_rs.is_reserved()) { 510 vm_exit_during_initialization("Unable to allocate memory for shared space", 511 err_msg(SIZE_FORMAT " bytes.", bytes)); 512 } 513 MetaspaceShared::initialize_shared_rs(&_rs); 514 } else 515 #endif 516 { 517 bool large_pages = should_commit_large_pages_when_reserving(bytes); 518 519 _rs = ReservedSpace(bytes, Metaspace::reserve_alignment(), large_pages); 520 } 521 522 if (_rs.is_reserved()) { 523 assert(_rs.base() != NULL, "Catch if we get a NULL address"); 524 assert(_rs.size() != 0, "Catch if we get a 0 size"); 525 assert_is_ptr_aligned(_rs.base(), Metaspace::reserve_alignment()); 526 assert_is_size_aligned(_rs.size(), Metaspace::reserve_alignment()); 527 528 MemTracker::record_virtual_memory_type((address)_rs.base(), mtClass); 529 } 530 } 531 532 void VirtualSpaceNode::purge(ChunkManager* chunk_manager) { 533 Metachunk* chunk = first_chunk(); 534 Metachunk* invalid_chunk = (Metachunk*) top(); 535 while (chunk < invalid_chunk ) { 536 assert(chunk->is_tagged_free(), "Should be tagged free"); 537 MetaWord* next = ((MetaWord*)chunk) + chunk->word_size(); 538 chunk_manager->remove_chunk(chunk); 539 assert(chunk->next() == NULL && 540 chunk->prev() == NULL, 541 "Was not removed from its list"); 542 chunk = (Metachunk*) next; 543 } 544 } 545 546 #ifdef ASSERT 547 uintx VirtualSpaceNode::container_count_slow() { 548 uintx count = 0; 549 Metachunk* chunk = first_chunk(); 550 Metachunk* invalid_chunk = (Metachunk*) top(); 551 while (chunk < invalid_chunk ) { 552 MetaWord* next = ((MetaWord*)chunk) + chunk->word_size(); 553 // Don't count the chunks on the free lists. Those are 554 // still part of the VirtualSpaceNode but not currently 555 // counted. 556 if (!chunk->is_tagged_free()) { 557 count++; 558 } 559 chunk = (Metachunk*) next; 560 } 561 return count; 562 } 563 #endif 564 565 // List of VirtualSpaces for metadata allocation. 566 class VirtualSpaceList : public CHeapObj<mtClass> { 567 friend class VirtualSpaceNode; 568 569 enum VirtualSpaceSizes { 570 VirtualSpaceSize = 256 * K 571 }; 572 573 // Head of the list 574 VirtualSpaceNode* _virtual_space_list; 575 // virtual space currently being used for allocations 576 VirtualSpaceNode* _current_virtual_space; 577 578 // Is this VirtualSpaceList used for the compressed class space 579 bool _is_class; 580 581 // Sum of reserved and committed memory in the virtual spaces 582 size_t _reserved_words; 583 size_t _committed_words; 584 585 // Number of virtual spaces 586 size_t _virtual_space_count; 587 588 ~VirtualSpaceList(); 589 590 VirtualSpaceNode* virtual_space_list() const { return _virtual_space_list; } 591 592 void set_virtual_space_list(VirtualSpaceNode* v) { 593 _virtual_space_list = v; 594 } 595 void set_current_virtual_space(VirtualSpaceNode* v) { 596 _current_virtual_space = v; 597 } 598 599 void link_vs(VirtualSpaceNode* new_entry); 600 601 // Get another virtual space and add it to the list. This 602 // is typically prompted by a failed attempt to allocate a chunk 603 // and is typically followed by the allocation of a chunk. 604 bool create_new_virtual_space(size_t vs_word_size); 605 606 // Chunk up the unused committed space in the current 607 // virtual space and add the chunks to the free list. 608 void retire_current_virtual_space(); 609 610 public: 611 VirtualSpaceList(size_t word_size); 612 VirtualSpaceList(ReservedSpace rs); 613 614 size_t free_bytes(); 615 616 Metachunk* get_new_chunk(size_t chunk_word_size, 617 size_t suggested_commit_granularity); 618 619 bool expand_node_by(VirtualSpaceNode* node, 620 size_t min_words, 621 size_t preferred_words); 622 623 bool expand_by(size_t min_words, 624 size_t preferred_words); 625 626 VirtualSpaceNode* current_virtual_space() { 627 return _current_virtual_space; 628 } 629 630 bool is_class() const { return _is_class; } 631 632 bool initialization_succeeded() { return _virtual_space_list != NULL; } 633 634 size_t reserved_words() { return _reserved_words; } 635 size_t reserved_bytes() { return reserved_words() * BytesPerWord; } 636 size_t committed_words() { return _committed_words; } 637 size_t committed_bytes() { return committed_words() * BytesPerWord; } 638 639 void inc_reserved_words(size_t v); 640 void dec_reserved_words(size_t v); 641 void inc_committed_words(size_t v); 642 void dec_committed_words(size_t v); 643 void inc_virtual_space_count(); 644 void dec_virtual_space_count(); 645 646 bool contains(const void* ptr); 647 648 // Unlink empty VirtualSpaceNodes and free it. 649 void purge(ChunkManager* chunk_manager); 650 651 void print_on(outputStream* st) const; 652 653 class VirtualSpaceListIterator : public StackObj { 654 VirtualSpaceNode* _virtual_spaces; 655 public: 656 VirtualSpaceListIterator(VirtualSpaceNode* virtual_spaces) : 657 _virtual_spaces(virtual_spaces) {} 658 659 bool repeat() { 660 return _virtual_spaces != NULL; 661 } 662 663 VirtualSpaceNode* get_next() { 664 VirtualSpaceNode* result = _virtual_spaces; 665 if (_virtual_spaces != NULL) { 666 _virtual_spaces = _virtual_spaces->next(); 667 } 668 return result; 669 } 670 }; 671 }; 672 673 class Metadebug : AllStatic { 674 // Debugging support for Metaspaces 675 static int _allocation_fail_alot_count; 676 677 public: 678 679 static void init_allocation_fail_alot_count(); 680 #ifdef ASSERT 681 static bool test_metadata_failure(); 682 #endif 683 }; 684 685 int Metadebug::_allocation_fail_alot_count = 0; 686 687 // SpaceManager - used by Metaspace to handle allocations 688 class SpaceManager : public CHeapObj<mtClass> { 689 friend class Metaspace; 690 friend class Metadebug; 691 692 private: 693 694 // protects allocations 695 Mutex* const _lock; 696 697 // Type of metadata allocated. 698 Metaspace::MetadataType _mdtype; 699 700 // List of chunks in use by this SpaceManager. Allocations 701 // are done from the current chunk. The list is used for deallocating 702 // chunks when the SpaceManager is freed. 703 Metachunk* _chunks_in_use[NumberOfInUseLists]; 704 Metachunk* _current_chunk; 705 706 // Maximum number of small chunks to allocate to a SpaceManager 707 static uint const _small_chunk_limit; 708 709 // Sum of all space in allocated chunks 710 size_t _allocated_blocks_words; 711 712 // Sum of all allocated chunks 713 size_t _allocated_chunks_words; 714 size_t _allocated_chunks_count; 715 716 // Free lists of blocks are per SpaceManager since they 717 // are assumed to be in chunks in use by the SpaceManager 718 // and all chunks in use by a SpaceManager are freed when 719 // the class loader using the SpaceManager is collected. 720 BlockFreelist* _block_freelists; 721 722 // protects virtualspace and chunk expansions 723 static const char* _expand_lock_name; 724 static const int _expand_lock_rank; 725 static Mutex* const _expand_lock; 726 727 private: 728 // Accessors 729 Metachunk* chunks_in_use(ChunkIndex index) const { return _chunks_in_use[index]; } 730 void set_chunks_in_use(ChunkIndex index, Metachunk* v) { 731 _chunks_in_use[index] = v; 732 } 733 734 BlockFreelist* block_freelists() const { return _block_freelists; } 735 736 Metaspace::MetadataType mdtype() { return _mdtype; } 737 738 VirtualSpaceList* vs_list() const { return Metaspace::get_space_list(_mdtype); } 739 ChunkManager* chunk_manager() const { return Metaspace::get_chunk_manager(_mdtype); } 740 741 Metachunk* current_chunk() const { return _current_chunk; } 742 void set_current_chunk(Metachunk* v) { 743 _current_chunk = v; 744 } 745 746 Metachunk* find_current_chunk(size_t word_size); 747 748 // Add chunk to the list of chunks in use 749 void add_chunk(Metachunk* v, bool make_current); 750 void retire_current_chunk(); 751 752 Mutex* lock() const { return _lock; } 753 754 protected: 755 void initialize(); 756 757 public: 758 SpaceManager(Metaspace::MetadataType mdtype, 759 Mutex* lock); 760 ~SpaceManager(); 761 762 enum ChunkMultiples { 763 MediumChunkMultiple = 4 764 }; 765 766 static size_t specialized_chunk_size(bool is_class) { return is_class ? ClassSpecializedChunk : SpecializedChunk; } 767 static size_t small_chunk_size(bool is_class) { return is_class ? ClassSmallChunk : SmallChunk; } 768 static size_t medium_chunk_size(bool is_class) { return is_class ? ClassMediumChunk : MediumChunk; } 769 770 static size_t smallest_chunk_size(bool is_class) { return specialized_chunk_size(is_class); } 771 772 // Accessors 773 bool is_class() const { return _mdtype == Metaspace::ClassType; } 774 775 size_t specialized_chunk_size() const { return specialized_chunk_size(is_class()); } 776 size_t small_chunk_size() const { return small_chunk_size(is_class()); } 777 size_t medium_chunk_size() const { return medium_chunk_size(is_class()); } 778 779 size_t smallest_chunk_size() const { return smallest_chunk_size(is_class()); } 780 781 size_t medium_chunk_bunch() const { return medium_chunk_size() * MediumChunkMultiple; } 782 783 size_t allocated_blocks_words() const { return _allocated_blocks_words; } 784 size_t allocated_blocks_bytes() const { return _allocated_blocks_words * BytesPerWord; } 785 size_t allocated_chunks_words() const { return _allocated_chunks_words; } 786 size_t allocated_chunks_bytes() const { return _allocated_chunks_words * BytesPerWord; } 787 size_t allocated_chunks_count() const { return _allocated_chunks_count; } 788 789 bool is_humongous(size_t word_size) { return word_size > medium_chunk_size(); } 790 791 static Mutex* expand_lock() { return _expand_lock; } 792 793 // Increment the per Metaspace and global running sums for Metachunks 794 // by the given size. This is used when a Metachunk to added to 795 // the in-use list. 796 void inc_size_metrics(size_t words); 797 // Increment the per Metaspace and global running sums Metablocks by the given 798 // size. This is used when a Metablock is allocated. 799 void inc_used_metrics(size_t words); 800 // Delete the portion of the running sums for this SpaceManager. That is, 801 // the globals running sums for the Metachunks and Metablocks are 802 // decremented for all the Metachunks in-use by this SpaceManager. 803 void dec_total_from_size_metrics(); 804 805 // Adjust the initial chunk size to match one of the fixed chunk list sizes, 806 // or return the unadjusted size if the requested size is humongous. 807 static size_t adjust_initial_chunk_size(size_t requested, bool is_class_space); 808 size_t adjust_initial_chunk_size(size_t requested) const; 809 810 // Get the initial chunks size for this metaspace type. 811 size_t get_initial_chunk_size(Metaspace::MetaspaceType type) const; 812 813 size_t sum_capacity_in_chunks_in_use() const; 814 size_t sum_used_in_chunks_in_use() const; 815 size_t sum_free_in_chunks_in_use() const; 816 size_t sum_waste_in_chunks_in_use() const; 817 size_t sum_waste_in_chunks_in_use(ChunkIndex index ) const; 818 819 size_t sum_count_in_chunks_in_use(); 820 size_t sum_count_in_chunks_in_use(ChunkIndex i); 821 822 Metachunk* get_new_chunk(size_t chunk_word_size); 823 824 // Block allocation and deallocation. 825 // Allocates a block from the current chunk 826 MetaWord* allocate(size_t word_size); 827 // Allocates a block from a small chunk 828 MetaWord* get_small_chunk_and_allocate(size_t word_size); 829 830 // Helper for allocations 831 MetaWord* allocate_work(size_t word_size); 832 833 // Returns a block to the per manager freelist 834 void deallocate(MetaWord* p, size_t word_size); 835 836 // Based on the allocation size and a minimum chunk size, 837 // returned chunk size (for expanding space for chunk allocation). 838 size_t calc_chunk_size(size_t allocation_word_size); 839 840 // Called when an allocation from the current chunk fails. 841 // Gets a new chunk (may require getting a new virtual space), 842 // and allocates from that chunk. 843 MetaWord* grow_and_allocate(size_t word_size); 844 845 // Notify memory usage to MemoryService. 846 void track_metaspace_memory_usage(); 847 848 // debugging support. 849 850 void dump(outputStream* const out) const; 851 void print_on(outputStream* st) const; 852 void locked_print_chunks_in_use_on(outputStream* st) const; 853 854 void verify(); 855 void verify_chunk_size(Metachunk* chunk); 856 #ifdef ASSERT 857 void verify_allocated_blocks_words(); 858 #endif 859 860 // This adjusts the size given to be greater than the minimum allocation size in 861 // words for data in metaspace. Esentially the minimum size is currently 3 words. 862 size_t get_allocation_word_size(size_t word_size) { 863 size_t byte_size = word_size * BytesPerWord; 864 865 size_t raw_bytes_size = MAX2(byte_size, sizeof(Metablock)); 866 raw_bytes_size = align_size_up(raw_bytes_size, Metachunk::object_alignment()); 867 868 size_t raw_word_size = raw_bytes_size / BytesPerWord; 869 assert(raw_word_size * BytesPerWord == raw_bytes_size, "Size problem"); 870 871 return raw_word_size; 872 } 873 }; 874 875 uint const SpaceManager::_small_chunk_limit = 4; 876 877 const char* SpaceManager::_expand_lock_name = 878 "SpaceManager chunk allocation lock"; 879 const int SpaceManager::_expand_lock_rank = Monitor::leaf - 1; 880 Mutex* const SpaceManager::_expand_lock = 881 new Mutex(SpaceManager::_expand_lock_rank, 882 SpaceManager::_expand_lock_name, 883 Mutex::_allow_vm_block_flag, 884 Monitor::_safepoint_check_never); 885 886 void VirtualSpaceNode::inc_container_count() { 887 assert_lock_strong(SpaceManager::expand_lock()); 888 _container_count++; 889 } 890 891 void VirtualSpaceNode::dec_container_count() { 892 assert_lock_strong(SpaceManager::expand_lock()); 893 _container_count--; 894 } 895 896 #ifdef ASSERT 897 void VirtualSpaceNode::verify_container_count() { 898 assert(_container_count == container_count_slow(), 899 "Inconsistency in container_count _container_count " UINTX_FORMAT 900 " container_count_slow() " UINTX_FORMAT, _container_count, container_count_slow()); 901 } 902 #endif 903 904 // BlockFreelist methods 905 906 BlockFreelist::BlockFreelist() : _dictionary(new BlockTreeDictionary()), _small_blocks(NULL) {} 907 908 BlockFreelist::~BlockFreelist() { 909 delete _dictionary; 910 if (_small_blocks != NULL) { 911 delete _small_blocks; 912 } 913 } 914 915 void BlockFreelist::return_block(MetaWord* p, size_t word_size) { 916 assert(word_size >= SmallBlocks::small_block_min_size(), "never return dark matter"); 917 918 Metablock* free_chunk = ::new (p) Metablock(word_size); 919 if (word_size < SmallBlocks::small_block_max_size()) { 920 small_blocks()->return_block(free_chunk, word_size); 921 } else { 922 dictionary()->return_chunk(free_chunk); 923 } 924 log_trace(gc, metaspace, freelist, blocks)("returning block at " INTPTR_FORMAT " size = " 925 SIZE_FORMAT, p2i(free_chunk), word_size); 926 } 927 928 MetaWord* BlockFreelist::get_block(size_t word_size) { 929 assert(word_size >= SmallBlocks::small_block_min_size(), "never get dark matter"); 930 931 // Try small_blocks first. 932 if (word_size < SmallBlocks::small_block_max_size()) { 933 // Don't create small_blocks() until needed. small_blocks() allocates the small block list for 934 // this space manager. 935 MetaWord* new_block = (MetaWord*) small_blocks()->get_block(word_size); 936 if (new_block != NULL) { 937 log_trace(gc, metaspace, freelist, blocks)("getting block at " INTPTR_FORMAT " size = " SIZE_FORMAT, 938 p2i(new_block), word_size); 939 return new_block; 940 } 941 } 942 943 if (word_size < BlockFreelist::min_dictionary_size()) { 944 // If allocation in small blocks fails, this is Dark Matter. Too small for dictionary. 945 return NULL; 946 } 947 948 Metablock* free_block = 949 dictionary()->get_chunk(word_size, FreeBlockDictionary<Metablock>::atLeast); 950 if (free_block == NULL) { 951 return NULL; 952 } 953 954 const size_t block_size = free_block->size(); 955 if (block_size > WasteMultiplier * word_size) { 956 return_block((MetaWord*)free_block, block_size); 957 return NULL; 958 } 959 960 MetaWord* new_block = (MetaWord*)free_block; 961 assert(block_size >= word_size, "Incorrect size of block from freelist"); 962 const size_t unused = block_size - word_size; 963 if (unused >= SmallBlocks::small_block_min_size()) { 964 return_block(new_block + word_size, unused); 965 } 966 967 log_trace(gc, metaspace, freelist, blocks)("getting block at " INTPTR_FORMAT " size = " SIZE_FORMAT, 968 p2i(new_block), word_size); 969 return new_block; 970 } 971 972 void BlockFreelist::print_on(outputStream* st) const { 973 dictionary()->print_free_lists(st); 974 if (_small_blocks != NULL) { 975 _small_blocks->print_on(st); 976 } 977 } 978 979 // VirtualSpaceNode methods 980 981 VirtualSpaceNode::~VirtualSpaceNode() { 982 _rs.release(); 983 #ifdef ASSERT 984 size_t word_size = sizeof(*this) / BytesPerWord; 985 Copy::fill_to_words((HeapWord*) this, word_size, 0xf1f1f1f1); 986 #endif 987 } 988 989 size_t VirtualSpaceNode::used_words_in_vs() const { 990 return pointer_delta(top(), bottom(), sizeof(MetaWord)); 991 } 992 993 // Space committed in the VirtualSpace 994 size_t VirtualSpaceNode::capacity_words_in_vs() const { 995 return pointer_delta(end(), bottom(), sizeof(MetaWord)); 996 } 997 998 size_t VirtualSpaceNode::free_words_in_vs() const { 999 return pointer_delta(end(), top(), sizeof(MetaWord)); 1000 } 1001 1002 // Allocates the chunk from the virtual space only. 1003 // This interface is also used internally for debugging. Not all 1004 // chunks removed here are necessarily used for allocation. 1005 Metachunk* VirtualSpaceNode::take_from_committed(size_t chunk_word_size) { 1006 // Bottom of the new chunk 1007 MetaWord* chunk_limit = top(); 1008 assert(chunk_limit != NULL, "Not safe to call this method"); 1009 1010 // The virtual spaces are always expanded by the 1011 // commit granularity to enforce the following condition. 1012 // Without this the is_available check will not work correctly. 1013 assert(_virtual_space.committed_size() == _virtual_space.actual_committed_size(), 1014 "The committed memory doesn't match the expanded memory."); 1015 1016 if (!is_available(chunk_word_size)) { 1017 Log(gc, metaspace, freelist) log; 1018 log.debug("VirtualSpaceNode::take_from_committed() not available " SIZE_FORMAT " words ", chunk_word_size); 1019 // Dump some information about the virtual space that is nearly full 1020 ResourceMark rm; 1021 print_on(log.debug_stream()); 1022 return NULL; 1023 } 1024 1025 // Take the space (bump top on the current virtual space). 1026 inc_top(chunk_word_size); 1027 1028 // Initialize the chunk 1029 Metachunk* result = ::new (chunk_limit) Metachunk(chunk_word_size, this); 1030 return result; 1031 } 1032 1033 1034 // Expand the virtual space (commit more of the reserved space) 1035 bool VirtualSpaceNode::expand_by(size_t min_words, size_t preferred_words) { 1036 size_t min_bytes = min_words * BytesPerWord; 1037 size_t preferred_bytes = preferred_words * BytesPerWord; 1038 1039 size_t uncommitted = virtual_space()->reserved_size() - virtual_space()->actual_committed_size(); 1040 1041 if (uncommitted < min_bytes) { 1042 return false; 1043 } 1044 1045 size_t commit = MIN2(preferred_bytes, uncommitted); 1046 bool result = virtual_space()->expand_by(commit, false); 1047 1048 assert(result, "Failed to commit memory"); 1049 1050 return result; 1051 } 1052 1053 Metachunk* VirtualSpaceNode::get_chunk_vs(size_t chunk_word_size) { 1054 assert_lock_strong(SpaceManager::expand_lock()); 1055 Metachunk* result = take_from_committed(chunk_word_size); 1056 if (result != NULL) { 1057 inc_container_count(); 1058 } 1059 return result; 1060 } 1061 1062 bool VirtualSpaceNode::initialize() { 1063 1064 if (!_rs.is_reserved()) { 1065 return false; 1066 } 1067 1068 // These are necessary restriction to make sure that the virtual space always 1069 // grows in steps of Metaspace::commit_alignment(). If both base and size are 1070 // aligned only the middle alignment of the VirtualSpace is used. 1071 assert_is_ptr_aligned(_rs.base(), Metaspace::commit_alignment()); 1072 assert_is_size_aligned(_rs.size(), Metaspace::commit_alignment()); 1073 1074 // ReservedSpaces marked as special will have the entire memory 1075 // pre-committed. Setting a committed size will make sure that 1076 // committed_size and actual_committed_size agrees. 1077 size_t pre_committed_size = _rs.special() ? _rs.size() : 0; 1078 1079 bool result = virtual_space()->initialize_with_granularity(_rs, pre_committed_size, 1080 Metaspace::commit_alignment()); 1081 if (result) { 1082 assert(virtual_space()->committed_size() == virtual_space()->actual_committed_size(), 1083 "Checking that the pre-committed memory was registered by the VirtualSpace"); 1084 1085 set_top((MetaWord*)virtual_space()->low()); 1086 set_reserved(MemRegion((HeapWord*)_rs.base(), 1087 (HeapWord*)(_rs.base() + _rs.size()))); 1088 1089 assert(reserved()->start() == (HeapWord*) _rs.base(), 1090 "Reserved start was not set properly " PTR_FORMAT 1091 " != " PTR_FORMAT, p2i(reserved()->start()), p2i(_rs.base())); 1092 assert(reserved()->word_size() == _rs.size() / BytesPerWord, 1093 "Reserved size was not set properly " SIZE_FORMAT 1094 " != " SIZE_FORMAT, reserved()->word_size(), 1095 _rs.size() / BytesPerWord); 1096 } 1097 1098 return result; 1099 } 1100 1101 void VirtualSpaceNode::print_on(outputStream* st) const { 1102 size_t used = used_words_in_vs(); 1103 size_t capacity = capacity_words_in_vs(); 1104 VirtualSpace* vs = virtual_space(); 1105 st->print_cr(" space @ " PTR_FORMAT " " SIZE_FORMAT "K, " SIZE_FORMAT_W(3) "%% used " 1106 "[" PTR_FORMAT ", " PTR_FORMAT ", " 1107 PTR_FORMAT ", " PTR_FORMAT ")", 1108 p2i(vs), capacity / K, 1109 capacity == 0 ? 0 : used * 100 / capacity, 1110 p2i(bottom()), p2i(top()), p2i(end()), 1111 p2i(vs->high_boundary())); 1112 } 1113 1114 #ifdef ASSERT 1115 void VirtualSpaceNode::mangle() { 1116 size_t word_size = capacity_words_in_vs(); 1117 Copy::fill_to_words((HeapWord*) low(), word_size, 0xf1f1f1f1); 1118 } 1119 #endif // ASSERT 1120 1121 // VirtualSpaceList methods 1122 // Space allocated from the VirtualSpace 1123 1124 VirtualSpaceList::~VirtualSpaceList() { 1125 VirtualSpaceListIterator iter(virtual_space_list()); 1126 while (iter.repeat()) { 1127 VirtualSpaceNode* vsl = iter.get_next(); 1128 delete vsl; 1129 } 1130 } 1131 1132 void VirtualSpaceList::inc_reserved_words(size_t v) { 1133 assert_lock_strong(SpaceManager::expand_lock()); 1134 _reserved_words = _reserved_words + v; 1135 } 1136 void VirtualSpaceList::dec_reserved_words(size_t v) { 1137 assert_lock_strong(SpaceManager::expand_lock()); 1138 _reserved_words = _reserved_words - v; 1139 } 1140 1141 #define assert_committed_below_limit() \ 1142 assert(MetaspaceAux::committed_bytes() <= MaxMetaspaceSize, \ 1143 "Too much committed memory. Committed: " SIZE_FORMAT \ 1144 " limit (MaxMetaspaceSize): " SIZE_FORMAT, \ 1145 MetaspaceAux::committed_bytes(), MaxMetaspaceSize); 1146 1147 void VirtualSpaceList::inc_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 void VirtualSpaceList::dec_committed_words(size_t v) { 1154 assert_lock_strong(SpaceManager::expand_lock()); 1155 _committed_words = _committed_words - v; 1156 1157 assert_committed_below_limit(); 1158 } 1159 1160 void VirtualSpaceList::inc_virtual_space_count() { 1161 assert_lock_strong(SpaceManager::expand_lock()); 1162 _virtual_space_count++; 1163 } 1164 void VirtualSpaceList::dec_virtual_space_count() { 1165 assert_lock_strong(SpaceManager::expand_lock()); 1166 _virtual_space_count--; 1167 } 1168 1169 void ChunkManager::remove_chunk(Metachunk* chunk) { 1170 size_t word_size = chunk->word_size(); 1171 ChunkIndex index = list_index(word_size); 1172 if (index != HumongousIndex) { 1173 free_chunks(index)->remove_chunk(chunk); 1174 } else { 1175 humongous_dictionary()->remove_chunk(chunk); 1176 } 1177 1178 // Chunk has been removed from the chunks free list, update counters. 1179 account_for_removed_chunk(chunk); 1180 } 1181 1182 // Walk the list of VirtualSpaceNodes and delete 1183 // nodes with a 0 container_count. Remove Metachunks in 1184 // the node from their respective freelists. 1185 void VirtualSpaceList::purge(ChunkManager* chunk_manager) { 1186 assert(SafepointSynchronize::is_at_safepoint(), "must be called at safepoint for contains to work"); 1187 assert_lock_strong(SpaceManager::expand_lock()); 1188 // Don't use a VirtualSpaceListIterator because this 1189 // list is being changed and a straightforward use of an iterator is not safe. 1190 VirtualSpaceNode* purged_vsl = NULL; 1191 VirtualSpaceNode* prev_vsl = virtual_space_list(); 1192 VirtualSpaceNode* next_vsl = prev_vsl; 1193 while (next_vsl != NULL) { 1194 VirtualSpaceNode* vsl = next_vsl; 1195 DEBUG_ONLY(vsl->verify_container_count();) 1196 next_vsl = vsl->next(); 1197 // Don't free the current virtual space since it will likely 1198 // be needed soon. 1199 if (vsl->container_count() == 0 && vsl != current_virtual_space()) { 1200 // Unlink it from the list 1201 if (prev_vsl == vsl) { 1202 // This is the case of the current node being the first node. 1203 assert(vsl == virtual_space_list(), "Expected to be the first node"); 1204 set_virtual_space_list(vsl->next()); 1205 } else { 1206 prev_vsl->set_next(vsl->next()); 1207 } 1208 1209 vsl->purge(chunk_manager); 1210 dec_reserved_words(vsl->reserved_words()); 1211 dec_committed_words(vsl->committed_words()); 1212 dec_virtual_space_count(); 1213 purged_vsl = vsl; 1214 delete vsl; 1215 } else { 1216 prev_vsl = vsl; 1217 } 1218 } 1219 #ifdef ASSERT 1220 if (purged_vsl != NULL) { 1221 // List should be stable enough to use an iterator here. 1222 VirtualSpaceListIterator iter(virtual_space_list()); 1223 while (iter.repeat()) { 1224 VirtualSpaceNode* vsl = iter.get_next(); 1225 assert(vsl != purged_vsl, "Purge of vsl failed"); 1226 } 1227 } 1228 #endif 1229 } 1230 1231 1232 // This function looks at the mmap regions in the metaspace without locking. 1233 // The chunks are added with store ordering and not deleted except for at 1234 // unloading time during a safepoint. 1235 bool VirtualSpaceList::contains(const void* ptr) { 1236 // List should be stable enough to use an iterator here because removing virtual 1237 // space nodes is only allowed at a safepoint. 1238 VirtualSpaceListIterator iter(virtual_space_list()); 1239 while (iter.repeat()) { 1240 VirtualSpaceNode* vsn = iter.get_next(); 1241 if (vsn->contains(ptr)) { 1242 return true; 1243 } 1244 } 1245 return false; 1246 } 1247 1248 void VirtualSpaceList::retire_current_virtual_space() { 1249 assert_lock_strong(SpaceManager::expand_lock()); 1250 1251 VirtualSpaceNode* vsn = current_virtual_space(); 1252 1253 ChunkManager* cm = is_class() ? Metaspace::chunk_manager_class() : 1254 Metaspace::chunk_manager_metadata(); 1255 1256 vsn->retire(cm); 1257 } 1258 1259 void VirtualSpaceNode::retire(ChunkManager* chunk_manager) { 1260 DEBUG_ONLY(verify_container_count();) 1261 for (int i = (int)MediumIndex; i >= (int)ZeroIndex; --i) { 1262 ChunkIndex index = (ChunkIndex)i; 1263 size_t chunk_size = chunk_manager->size_by_index(index); 1264 1265 while (free_words_in_vs() >= chunk_size) { 1266 Metachunk* chunk = get_chunk_vs(chunk_size); 1267 assert(chunk != NULL, "allocation should have been successful"); 1268 1269 chunk_manager->return_single_chunk(index, chunk); 1270 } 1271 DEBUG_ONLY(verify_container_count();) 1272 } 1273 assert(free_words_in_vs() == 0, "should be empty now"); 1274 } 1275 1276 VirtualSpaceList::VirtualSpaceList(size_t word_size) : 1277 _is_class(false), 1278 _virtual_space_list(NULL), 1279 _current_virtual_space(NULL), 1280 _reserved_words(0), 1281 _committed_words(0), 1282 _virtual_space_count(0) { 1283 MutexLockerEx cl(SpaceManager::expand_lock(), 1284 Mutex::_no_safepoint_check_flag); 1285 create_new_virtual_space(word_size); 1286 } 1287 1288 VirtualSpaceList::VirtualSpaceList(ReservedSpace rs) : 1289 _is_class(true), 1290 _virtual_space_list(NULL), 1291 _current_virtual_space(NULL), 1292 _reserved_words(0), 1293 _committed_words(0), 1294 _virtual_space_count(0) { 1295 MutexLockerEx cl(SpaceManager::expand_lock(), 1296 Mutex::_no_safepoint_check_flag); 1297 VirtualSpaceNode* class_entry = new VirtualSpaceNode(rs); 1298 bool succeeded = class_entry->initialize(); 1299 if (succeeded) { 1300 link_vs(class_entry); 1301 } 1302 } 1303 1304 size_t VirtualSpaceList::free_bytes() { 1305 return virtual_space_list()->free_words_in_vs() * BytesPerWord; 1306 } 1307 1308 // Allocate another meta virtual space and add it to the list. 1309 bool VirtualSpaceList::create_new_virtual_space(size_t vs_word_size) { 1310 assert_lock_strong(SpaceManager::expand_lock()); 1311 1312 if (is_class()) { 1313 assert(false, "We currently don't support more than one VirtualSpace for" 1314 " the compressed class space. The initialization of the" 1315 " CCS uses another code path and should not hit this path."); 1316 return false; 1317 } 1318 1319 if (vs_word_size == 0) { 1320 assert(false, "vs_word_size should always be at least _reserve_alignment large."); 1321 return false; 1322 } 1323 1324 // Reserve the space 1325 size_t vs_byte_size = vs_word_size * BytesPerWord; 1326 assert_is_size_aligned(vs_byte_size, Metaspace::reserve_alignment()); 1327 1328 // Allocate the meta virtual space and initialize it. 1329 VirtualSpaceNode* new_entry = new VirtualSpaceNode(vs_byte_size); 1330 if (!new_entry->initialize()) { 1331 delete new_entry; 1332 return false; 1333 } else { 1334 assert(new_entry->reserved_words() == vs_word_size, 1335 "Reserved memory size differs from requested memory size"); 1336 // ensure lock-free iteration sees fully initialized node 1337 OrderAccess::storestore(); 1338 link_vs(new_entry); 1339 return true; 1340 } 1341 } 1342 1343 void VirtualSpaceList::link_vs(VirtualSpaceNode* new_entry) { 1344 if (virtual_space_list() == NULL) { 1345 set_virtual_space_list(new_entry); 1346 } else { 1347 current_virtual_space()->set_next(new_entry); 1348 } 1349 set_current_virtual_space(new_entry); 1350 inc_reserved_words(new_entry->reserved_words()); 1351 inc_committed_words(new_entry->committed_words()); 1352 inc_virtual_space_count(); 1353 #ifdef ASSERT 1354 new_entry->mangle(); 1355 #endif 1356 if (log_is_enabled(Trace, gc, metaspace)) { 1357 Log(gc, metaspace) log; 1358 VirtualSpaceNode* vsl = current_virtual_space(); 1359 ResourceMark rm; 1360 vsl->print_on(log.trace_stream()); 1361 } 1362 } 1363 1364 bool VirtualSpaceList::expand_node_by(VirtualSpaceNode* node, 1365 size_t min_words, 1366 size_t preferred_words) { 1367 size_t before = node->committed_words(); 1368 1369 bool result = node->expand_by(min_words, preferred_words); 1370 1371 size_t after = node->committed_words(); 1372 1373 // after and before can be the same if the memory was pre-committed. 1374 assert(after >= before, "Inconsistency"); 1375 inc_committed_words(after - before); 1376 1377 return result; 1378 } 1379 1380 bool VirtualSpaceList::expand_by(size_t min_words, size_t preferred_words) { 1381 assert_is_size_aligned(min_words, Metaspace::commit_alignment_words()); 1382 assert_is_size_aligned(preferred_words, Metaspace::commit_alignment_words()); 1383 assert(min_words <= preferred_words, "Invalid arguments"); 1384 1385 if (!MetaspaceGC::can_expand(min_words, this->is_class())) { 1386 return false; 1387 } 1388 1389 size_t allowed_expansion_words = MetaspaceGC::allowed_expansion(); 1390 if (allowed_expansion_words < min_words) { 1391 return false; 1392 } 1393 1394 size_t max_expansion_words = MIN2(preferred_words, allowed_expansion_words); 1395 1396 // Commit more memory from the the current virtual space. 1397 bool vs_expanded = expand_node_by(current_virtual_space(), 1398 min_words, 1399 max_expansion_words); 1400 if (vs_expanded) { 1401 return true; 1402 } 1403 retire_current_virtual_space(); 1404 1405 // Get another virtual space. 1406 size_t grow_vs_words = MAX2((size_t)VirtualSpaceSize, preferred_words); 1407 grow_vs_words = align_size_up(grow_vs_words, Metaspace::reserve_alignment_words()); 1408 1409 if (create_new_virtual_space(grow_vs_words)) { 1410 if (current_virtual_space()->is_pre_committed()) { 1411 // The memory was pre-committed, so we are done here. 1412 assert(min_words <= current_virtual_space()->committed_words(), 1413 "The new VirtualSpace was pre-committed, so it" 1414 "should be large enough to fit the alloc request."); 1415 return true; 1416 } 1417 1418 return expand_node_by(current_virtual_space(), 1419 min_words, 1420 max_expansion_words); 1421 } 1422 1423 return false; 1424 } 1425 1426 Metachunk* VirtualSpaceList::get_new_chunk(size_t chunk_word_size, size_t suggested_commit_granularity) { 1427 1428 // Allocate a chunk out of the current virtual space. 1429 Metachunk* next = current_virtual_space()->get_chunk_vs(chunk_word_size); 1430 1431 if (next != NULL) { 1432 return next; 1433 } 1434 1435 // The expand amount is currently only determined by the requested sizes 1436 // and not how much committed memory is left in the current virtual space. 1437 1438 size_t min_word_size = align_size_up(chunk_word_size, Metaspace::commit_alignment_words()); 1439 size_t preferred_word_size = align_size_up(suggested_commit_granularity, Metaspace::commit_alignment_words()); 1440 if (min_word_size >= preferred_word_size) { 1441 // Can happen when humongous chunks are allocated. 1442 preferred_word_size = min_word_size; 1443 } 1444 1445 bool expanded = expand_by(min_word_size, preferred_word_size); 1446 if (expanded) { 1447 next = current_virtual_space()->get_chunk_vs(chunk_word_size); 1448 assert(next != NULL, "The allocation was expected to succeed after the expansion"); 1449 } 1450 1451 return next; 1452 } 1453 1454 void VirtualSpaceList::print_on(outputStream* st) const { 1455 VirtualSpaceListIterator iter(virtual_space_list()); 1456 while (iter.repeat()) { 1457 VirtualSpaceNode* node = iter.get_next(); 1458 node->print_on(st); 1459 } 1460 } 1461 1462 // MetaspaceGC methods 1463 1464 // VM_CollectForMetadataAllocation is the vm operation used to GC. 1465 // Within the VM operation after the GC the attempt to allocate the metadata 1466 // should succeed. If the GC did not free enough space for the metaspace 1467 // allocation, the HWM is increased so that another virtualspace will be 1468 // allocated for the metadata. With perm gen the increase in the perm 1469 // gen had bounds, MinMetaspaceExpansion and MaxMetaspaceExpansion. The 1470 // metaspace policy uses those as the small and large steps for the HWM. 1471 // 1472 // After the GC the compute_new_size() for MetaspaceGC is called to 1473 // resize the capacity of the metaspaces. The current implementation 1474 // is based on the flags MinMetaspaceFreeRatio and MaxMetaspaceFreeRatio used 1475 // to resize the Java heap by some GC's. New flags can be implemented 1476 // if really needed. MinMetaspaceFreeRatio is used to calculate how much 1477 // free space is desirable in the metaspace capacity to decide how much 1478 // to increase the HWM. MaxMetaspaceFreeRatio is used to decide how much 1479 // free space is desirable in the metaspace capacity before decreasing 1480 // the HWM. 1481 1482 // Calculate the amount to increase the high water mark (HWM). 1483 // Increase by a minimum amount (MinMetaspaceExpansion) so that 1484 // another expansion is not requested too soon. If that is not 1485 // enough to satisfy the allocation, increase by MaxMetaspaceExpansion. 1486 // If that is still not enough, expand by the size of the allocation 1487 // plus some. 1488 size_t MetaspaceGC::delta_capacity_until_GC(size_t bytes) { 1489 size_t min_delta = MinMetaspaceExpansion; 1490 size_t max_delta = MaxMetaspaceExpansion; 1491 size_t delta = align_size_up(bytes, Metaspace::commit_alignment()); 1492 1493 if (delta <= min_delta) { 1494 delta = min_delta; 1495 } else if (delta <= max_delta) { 1496 // Don't want to hit the high water mark on the next 1497 // allocation so make the delta greater than just enough 1498 // for this allocation. 1499 delta = max_delta; 1500 } else { 1501 // This allocation is large but the next ones are probably not 1502 // so increase by the minimum. 1503 delta = delta + min_delta; 1504 } 1505 1506 assert_is_size_aligned(delta, Metaspace::commit_alignment()); 1507 1508 return delta; 1509 } 1510 1511 size_t MetaspaceGC::capacity_until_GC() { 1512 size_t value = (size_t)OrderAccess::load_ptr_acquire(&_capacity_until_GC); 1513 assert(value >= MetaspaceSize, "Not initialized properly?"); 1514 return value; 1515 } 1516 1517 bool MetaspaceGC::inc_capacity_until_GC(size_t v, size_t* new_cap_until_GC, size_t* old_cap_until_GC) { 1518 assert_is_size_aligned(v, Metaspace::commit_alignment()); 1519 1520 size_t capacity_until_GC = (size_t) _capacity_until_GC; 1521 size_t new_value = capacity_until_GC + v; 1522 1523 if (new_value < capacity_until_GC) { 1524 // The addition wrapped around, set new_value to aligned max value. 1525 new_value = align_size_down(max_uintx, Metaspace::commit_alignment()); 1526 } 1527 1528 intptr_t expected = (intptr_t) capacity_until_GC; 1529 intptr_t actual = Atomic::cmpxchg_ptr((intptr_t) new_value, &_capacity_until_GC, expected); 1530 1531 if (expected != actual) { 1532 return false; 1533 } 1534 1535 if (new_cap_until_GC != NULL) { 1536 *new_cap_until_GC = new_value; 1537 } 1538 if (old_cap_until_GC != NULL) { 1539 *old_cap_until_GC = capacity_until_GC; 1540 } 1541 return true; 1542 } 1543 1544 size_t MetaspaceGC::dec_capacity_until_GC(size_t v) { 1545 assert_is_size_aligned(v, Metaspace::commit_alignment()); 1546 1547 return (size_t)Atomic::add_ptr(-(intptr_t)v, &_capacity_until_GC); 1548 } 1549 1550 void MetaspaceGC::initialize() { 1551 // Set the high-water mark to MaxMetapaceSize during VM initializaton since 1552 // we can't do a GC during initialization. 1553 _capacity_until_GC = MaxMetaspaceSize; 1554 } 1555 1556 void MetaspaceGC::post_initialize() { 1557 // Reset the high-water mark once the VM initialization is done. 1558 _capacity_until_GC = MAX2(MetaspaceAux::committed_bytes(), MetaspaceSize); 1559 } 1560 1561 bool MetaspaceGC::can_expand(size_t word_size, bool is_class) { 1562 // Check if the compressed class space is full. 1563 if (is_class && Metaspace::using_class_space()) { 1564 size_t class_committed = MetaspaceAux::committed_bytes(Metaspace::ClassType); 1565 if (class_committed + word_size * BytesPerWord > CompressedClassSpaceSize) { 1566 return false; 1567 } 1568 } 1569 1570 // Check if the user has imposed a limit on the metaspace memory. 1571 size_t committed_bytes = MetaspaceAux::committed_bytes(); 1572 if (committed_bytes + word_size * BytesPerWord > MaxMetaspaceSize) { 1573 return false; 1574 } 1575 1576 return true; 1577 } 1578 1579 size_t MetaspaceGC::allowed_expansion() { 1580 size_t committed_bytes = MetaspaceAux::committed_bytes(); 1581 size_t capacity_until_gc = capacity_until_GC(); 1582 1583 assert(capacity_until_gc >= committed_bytes, 1584 "capacity_until_gc: " SIZE_FORMAT " < committed_bytes: " SIZE_FORMAT, 1585 capacity_until_gc, committed_bytes); 1586 1587 size_t left_until_max = MaxMetaspaceSize - committed_bytes; 1588 size_t left_until_GC = capacity_until_gc - committed_bytes; 1589 size_t left_to_commit = MIN2(left_until_GC, left_until_max); 1590 1591 return left_to_commit / BytesPerWord; 1592 } 1593 1594 void MetaspaceGC::compute_new_size() { 1595 assert(_shrink_factor <= 100, "invalid shrink factor"); 1596 uint current_shrink_factor = _shrink_factor; 1597 _shrink_factor = 0; 1598 1599 // Using committed_bytes() for used_after_gc is an overestimation, since the 1600 // chunk free lists are included in committed_bytes() and the memory in an 1601 // un-fragmented chunk free list is available for future allocations. 1602 // However, if the chunk free lists becomes fragmented, then the memory may 1603 // not be available for future allocations and the memory is therefore "in use". 1604 // Including the chunk free lists in the definition of "in use" is therefore 1605 // necessary. Not including the chunk free lists can cause capacity_until_GC to 1606 // shrink below committed_bytes() and this has caused serious bugs in the past. 1607 const size_t used_after_gc = MetaspaceAux::committed_bytes(); 1608 const size_t capacity_until_GC = MetaspaceGC::capacity_until_GC(); 1609 1610 const double minimum_free_percentage = MinMetaspaceFreeRatio / 100.0; 1611 const double maximum_used_percentage = 1.0 - minimum_free_percentage; 1612 1613 const double min_tmp = used_after_gc / maximum_used_percentage; 1614 size_t minimum_desired_capacity = 1615 (size_t)MIN2(min_tmp, double(max_uintx)); 1616 // Don't shrink less than the initial generation size 1617 minimum_desired_capacity = MAX2(minimum_desired_capacity, 1618 MetaspaceSize); 1619 1620 log_trace(gc, metaspace)("MetaspaceGC::compute_new_size: "); 1621 log_trace(gc, metaspace)(" minimum_free_percentage: %6.2f maximum_used_percentage: %6.2f", 1622 minimum_free_percentage, maximum_used_percentage); 1623 log_trace(gc, metaspace)(" used_after_gc : %6.1fKB", used_after_gc / (double) K); 1624 1625 1626 size_t shrink_bytes = 0; 1627 if (capacity_until_GC < minimum_desired_capacity) { 1628 // If we have less capacity below the metaspace HWM, then 1629 // increment the HWM. 1630 size_t expand_bytes = minimum_desired_capacity - capacity_until_GC; 1631 expand_bytes = align_size_up(expand_bytes, Metaspace::commit_alignment()); 1632 // Don't expand unless it's significant 1633 if (expand_bytes >= MinMetaspaceExpansion) { 1634 size_t new_capacity_until_GC = 0; 1635 bool succeeded = MetaspaceGC::inc_capacity_until_GC(expand_bytes, &new_capacity_until_GC); 1636 assert(succeeded, "Should always succesfully increment HWM when at safepoint"); 1637 1638 Metaspace::tracer()->report_gc_threshold(capacity_until_GC, 1639 new_capacity_until_GC, 1640 MetaspaceGCThresholdUpdater::ComputeNewSize); 1641 log_trace(gc, metaspace)(" expanding: minimum_desired_capacity: %6.1fKB expand_bytes: %6.1fKB MinMetaspaceExpansion: %6.1fKB new metaspace HWM: %6.1fKB", 1642 minimum_desired_capacity / (double) K, 1643 expand_bytes / (double) K, 1644 MinMetaspaceExpansion / (double) K, 1645 new_capacity_until_GC / (double) K); 1646 } 1647 return; 1648 } 1649 1650 // No expansion, now see if we want to shrink 1651 // We would never want to shrink more than this 1652 assert(capacity_until_GC >= minimum_desired_capacity, 1653 SIZE_FORMAT " >= " SIZE_FORMAT, 1654 capacity_until_GC, minimum_desired_capacity); 1655 size_t max_shrink_bytes = capacity_until_GC - minimum_desired_capacity; 1656 1657 // Should shrinking be considered? 1658 if (MaxMetaspaceFreeRatio < 100) { 1659 const double maximum_free_percentage = MaxMetaspaceFreeRatio / 100.0; 1660 const double minimum_used_percentage = 1.0 - maximum_free_percentage; 1661 const double max_tmp = used_after_gc / minimum_used_percentage; 1662 size_t maximum_desired_capacity = (size_t)MIN2(max_tmp, double(max_uintx)); 1663 maximum_desired_capacity = MAX2(maximum_desired_capacity, 1664 MetaspaceSize); 1665 log_trace(gc, metaspace)(" maximum_free_percentage: %6.2f minimum_used_percentage: %6.2f", 1666 maximum_free_percentage, minimum_used_percentage); 1667 log_trace(gc, metaspace)(" minimum_desired_capacity: %6.1fKB maximum_desired_capacity: %6.1fKB", 1668 minimum_desired_capacity / (double) K, maximum_desired_capacity / (double) K); 1669 1670 assert(minimum_desired_capacity <= maximum_desired_capacity, 1671 "sanity check"); 1672 1673 if (capacity_until_GC > maximum_desired_capacity) { 1674 // Capacity too large, compute shrinking size 1675 shrink_bytes = capacity_until_GC - maximum_desired_capacity; 1676 // We don't want shrink all the way back to initSize if people call 1677 // System.gc(), because some programs do that between "phases" and then 1678 // we'd just have to grow the heap up again for the next phase. So we 1679 // damp the shrinking: 0% on the first call, 10% on the second call, 40% 1680 // on the third call, and 100% by the fourth call. But if we recompute 1681 // size without shrinking, it goes back to 0%. 1682 shrink_bytes = shrink_bytes / 100 * current_shrink_factor; 1683 1684 shrink_bytes = align_size_down(shrink_bytes, Metaspace::commit_alignment()); 1685 1686 assert(shrink_bytes <= max_shrink_bytes, 1687 "invalid shrink size " SIZE_FORMAT " not <= " SIZE_FORMAT, 1688 shrink_bytes, max_shrink_bytes); 1689 if (current_shrink_factor == 0) { 1690 _shrink_factor = 10; 1691 } else { 1692 _shrink_factor = MIN2(current_shrink_factor * 4, (uint) 100); 1693 } 1694 log_trace(gc, metaspace)(" shrinking: initThreshold: %.1fK maximum_desired_capacity: %.1fK", 1695 MetaspaceSize / (double) K, maximum_desired_capacity / (double) K); 1696 log_trace(gc, metaspace)(" shrink_bytes: %.1fK current_shrink_factor: %d new shrink factor: %d MinMetaspaceExpansion: %.1fK", 1697 shrink_bytes / (double) K, current_shrink_factor, _shrink_factor, MinMetaspaceExpansion / (double) K); 1698 } 1699 } 1700 1701 // Don't shrink unless it's significant 1702 if (shrink_bytes >= MinMetaspaceExpansion && 1703 ((capacity_until_GC - shrink_bytes) >= MetaspaceSize)) { 1704 size_t new_capacity_until_GC = MetaspaceGC::dec_capacity_until_GC(shrink_bytes); 1705 Metaspace::tracer()->report_gc_threshold(capacity_until_GC, 1706 new_capacity_until_GC, 1707 MetaspaceGCThresholdUpdater::ComputeNewSize); 1708 } 1709 } 1710 1711 // Metadebug methods 1712 1713 void Metadebug::init_allocation_fail_alot_count() { 1714 if (MetadataAllocationFailALot) { 1715 _allocation_fail_alot_count = 1716 1+(long)((double)MetadataAllocationFailALotInterval*os::random()/(max_jint+1.0)); 1717 } 1718 } 1719 1720 #ifdef ASSERT 1721 bool Metadebug::test_metadata_failure() { 1722 if (MetadataAllocationFailALot && 1723 Threads::is_vm_complete()) { 1724 if (_allocation_fail_alot_count > 0) { 1725 _allocation_fail_alot_count--; 1726 } else { 1727 log_trace(gc, metaspace, freelist)("Metadata allocation failing for MetadataAllocationFailALot"); 1728 init_allocation_fail_alot_count(); 1729 return true; 1730 } 1731 } 1732 return false; 1733 } 1734 #endif 1735 1736 // ChunkManager methods 1737 1738 size_t ChunkManager::free_chunks_total_words() { 1739 return _free_chunks_total; 1740 } 1741 1742 size_t ChunkManager::free_chunks_total_bytes() { 1743 return free_chunks_total_words() * BytesPerWord; 1744 } 1745 1746 // Update internal accounting after a chunk was added 1747 void ChunkManager::account_for_added_chunk(const Metachunk* c) { 1748 assert_lock_strong(SpaceManager::expand_lock()); 1749 _free_chunks_count ++; 1750 _free_chunks_total += c->word_size(); 1751 } 1752 1753 // Update internal accounting after a chunk was removed 1754 void ChunkManager::account_for_removed_chunk(const Metachunk* c) { 1755 assert_lock_strong(SpaceManager::expand_lock()); 1756 assert(_free_chunks_count >= 1, 1757 "ChunkManager::_free_chunks_count: about to go negative (" SIZE_FORMAT ").", _free_chunks_count); 1758 assert(_free_chunks_total >= c->word_size(), 1759 "ChunkManager::_free_chunks_total: about to go negative" 1760 "(now: " SIZE_FORMAT ", decrement value: " SIZE_FORMAT ").", _free_chunks_total, c->word_size()); 1761 _free_chunks_count --; 1762 _free_chunks_total -= c->word_size(); 1763 } 1764 1765 size_t ChunkManager::free_chunks_count() { 1766 #ifdef ASSERT 1767 if (!UseConcMarkSweepGC && !SpaceManager::expand_lock()->is_locked()) { 1768 MutexLockerEx cl(SpaceManager::expand_lock(), 1769 Mutex::_no_safepoint_check_flag); 1770 // This lock is only needed in debug because the verification 1771 // of the _free_chunks_totals walks the list of free chunks 1772 slow_locked_verify_free_chunks_count(); 1773 } 1774 #endif 1775 return _free_chunks_count; 1776 } 1777 1778 ChunkIndex ChunkManager::list_index(size_t size) { 1779 if (size_by_index(SpecializedIndex) == size) { 1780 return SpecializedIndex; 1781 } 1782 if (size_by_index(SmallIndex) == size) { 1783 return SmallIndex; 1784 } 1785 const size_t med_size = size_by_index(MediumIndex); 1786 if (med_size == size) { 1787 return MediumIndex; 1788 } 1789 1790 assert(size > med_size, "Not a humongous chunk"); 1791 return HumongousIndex; 1792 } 1793 1794 size_t ChunkManager::size_by_index(ChunkIndex index) { 1795 index_bounds_check(index); 1796 assert(index != HumongousIndex, "Do not call for humongous chunks."); 1797 return free_chunks(index)->size(); 1798 } 1799 1800 void ChunkManager::locked_verify_free_chunks_total() { 1801 assert_lock_strong(SpaceManager::expand_lock()); 1802 assert(sum_free_chunks() == _free_chunks_total, 1803 "_free_chunks_total " SIZE_FORMAT " is not the" 1804 " same as sum " SIZE_FORMAT, _free_chunks_total, 1805 sum_free_chunks()); 1806 } 1807 1808 void ChunkManager::verify_free_chunks_total() { 1809 MutexLockerEx cl(SpaceManager::expand_lock(), 1810 Mutex::_no_safepoint_check_flag); 1811 locked_verify_free_chunks_total(); 1812 } 1813 1814 void ChunkManager::locked_verify_free_chunks_count() { 1815 assert_lock_strong(SpaceManager::expand_lock()); 1816 assert(sum_free_chunks_count() == _free_chunks_count, 1817 "_free_chunks_count " SIZE_FORMAT " is not the" 1818 " same as sum " SIZE_FORMAT, _free_chunks_count, 1819 sum_free_chunks_count()); 1820 } 1821 1822 void ChunkManager::verify_free_chunks_count() { 1823 #ifdef ASSERT 1824 MutexLockerEx cl(SpaceManager::expand_lock(), 1825 Mutex::_no_safepoint_check_flag); 1826 locked_verify_free_chunks_count(); 1827 #endif 1828 } 1829 1830 void ChunkManager::verify() { 1831 MutexLockerEx cl(SpaceManager::expand_lock(), 1832 Mutex::_no_safepoint_check_flag); 1833 locked_verify(); 1834 } 1835 1836 void ChunkManager::locked_verify() { 1837 locked_verify_free_chunks_count(); 1838 locked_verify_free_chunks_total(); 1839 } 1840 1841 void ChunkManager::locked_print_free_chunks(outputStream* st) { 1842 assert_lock_strong(SpaceManager::expand_lock()); 1843 st->print_cr("Free chunk total " SIZE_FORMAT " count " SIZE_FORMAT, 1844 _free_chunks_total, _free_chunks_count); 1845 } 1846 1847 void ChunkManager::locked_print_sum_free_chunks(outputStream* st) { 1848 assert_lock_strong(SpaceManager::expand_lock()); 1849 st->print_cr("Sum free chunk total " SIZE_FORMAT " count " SIZE_FORMAT, 1850 sum_free_chunks(), sum_free_chunks_count()); 1851 } 1852 1853 ChunkList* ChunkManager::free_chunks(ChunkIndex index) { 1854 assert(index == SpecializedIndex || index == SmallIndex || index == MediumIndex, 1855 "Bad index: %d", (int)index); 1856 1857 return &_free_chunks[index]; 1858 } 1859 1860 // These methods that sum the free chunk lists are used in printing 1861 // methods that are used in product builds. 1862 size_t ChunkManager::sum_free_chunks() { 1863 assert_lock_strong(SpaceManager::expand_lock()); 1864 size_t result = 0; 1865 for (ChunkIndex i = ZeroIndex; i < NumberOfFreeLists; i = next_chunk_index(i)) { 1866 ChunkList* list = free_chunks(i); 1867 1868 if (list == NULL) { 1869 continue; 1870 } 1871 1872 result = result + list->count() * list->size(); 1873 } 1874 result = result + humongous_dictionary()->total_size(); 1875 return result; 1876 } 1877 1878 size_t ChunkManager::sum_free_chunks_count() { 1879 assert_lock_strong(SpaceManager::expand_lock()); 1880 size_t count = 0; 1881 for (ChunkIndex i = ZeroIndex; i < NumberOfFreeLists; i = next_chunk_index(i)) { 1882 ChunkList* list = free_chunks(i); 1883 if (list == NULL) { 1884 continue; 1885 } 1886 count = count + list->count(); 1887 } 1888 count = count + humongous_dictionary()->total_free_blocks(); 1889 return count; 1890 } 1891 1892 ChunkList* ChunkManager::find_free_chunks_list(size_t word_size) { 1893 ChunkIndex index = list_index(word_size); 1894 assert(index < HumongousIndex, "No humongous list"); 1895 return free_chunks(index); 1896 } 1897 1898 Metachunk* ChunkManager::free_chunks_get(size_t word_size) { 1899 assert_lock_strong(SpaceManager::expand_lock()); 1900 1901 slow_locked_verify(); 1902 1903 Metachunk* chunk = NULL; 1904 if (list_index(word_size) != HumongousIndex) { 1905 ChunkList* free_list = find_free_chunks_list(word_size); 1906 assert(free_list != NULL, "Sanity check"); 1907 1908 chunk = free_list->head(); 1909 1910 if (chunk == NULL) { 1911 return NULL; 1912 } 1913 1914 // Remove the chunk as the head of the list. 1915 free_list->remove_chunk(chunk); 1916 1917 log_trace(gc, metaspace, freelist)("ChunkManager::free_chunks_get: free_list " PTR_FORMAT " head " PTR_FORMAT " size " SIZE_FORMAT, 1918 p2i(free_list), p2i(chunk), chunk->word_size()); 1919 } else { 1920 chunk = humongous_dictionary()->get_chunk( 1921 word_size, 1922 FreeBlockDictionary<Metachunk>::atLeast); 1923 1924 if (chunk == NULL) { 1925 return NULL; 1926 } 1927 1928 log_debug(gc, metaspace, alloc)("Free list allocate humongous chunk size " SIZE_FORMAT " for requested size " SIZE_FORMAT " waste " SIZE_FORMAT, 1929 chunk->word_size(), word_size, chunk->word_size() - word_size); 1930 } 1931 1932 // Chunk has been removed from the chunk manager; update counters. 1933 account_for_removed_chunk(chunk); 1934 1935 // Remove it from the links to this freelist 1936 chunk->set_next(NULL); 1937 chunk->set_prev(NULL); 1938 #ifdef ASSERT 1939 // Chunk is no longer on any freelist. Setting to false make container_count_slow() 1940 // work. 1941 chunk->set_is_tagged_free(false); 1942 #endif 1943 chunk->container()->inc_container_count(); 1944 1945 slow_locked_verify(); 1946 return chunk; 1947 } 1948 1949 Metachunk* ChunkManager::chunk_freelist_allocate(size_t word_size) { 1950 assert_lock_strong(SpaceManager::expand_lock()); 1951 slow_locked_verify(); 1952 1953 // Take from the beginning of the list 1954 Metachunk* chunk = free_chunks_get(word_size); 1955 if (chunk == NULL) { 1956 return NULL; 1957 } 1958 1959 assert((word_size <= chunk->word_size()) || 1960 (list_index(chunk->word_size()) == HumongousIndex), 1961 "Non-humongous variable sized chunk"); 1962 Log(gc, metaspace, freelist) log; 1963 if (log.is_debug()) { 1964 size_t list_count; 1965 if (list_index(word_size) < HumongousIndex) { 1966 ChunkList* list = find_free_chunks_list(word_size); 1967 list_count = list->count(); 1968 } else { 1969 list_count = humongous_dictionary()->total_count(); 1970 } 1971 log.debug("ChunkManager::chunk_freelist_allocate: " PTR_FORMAT " chunk " PTR_FORMAT " size " SIZE_FORMAT " count " SIZE_FORMAT " ", 1972 p2i(this), p2i(chunk), chunk->word_size(), list_count); 1973 ResourceMark rm; 1974 locked_print_free_chunks(log.debug_stream()); 1975 } 1976 1977 return chunk; 1978 } 1979 1980 void ChunkManager::return_single_chunk(ChunkIndex index, Metachunk* chunk) { 1981 assert_lock_strong(SpaceManager::expand_lock()); 1982 assert(chunk != NULL, "Expected chunk."); 1983 assert(chunk->container() != NULL, "Container should have been set."); 1984 assert(chunk->is_tagged_free() == false, "Chunk should be in use."); 1985 index_bounds_check(index); 1986 1987 // Note: mangle *before* returning the chunk to the freelist or dictionary. It does not 1988 // matter for the freelist (non-humongous chunks), but the humongous chunk dictionary 1989 // keeps tree node pointers in the chunk payload area which mangle will overwrite. 1990 NOT_PRODUCT(chunk->mangle(badMetaWordVal);) 1991 1992 if (index != HumongousIndex) { 1993 // Return non-humongous chunk to freelist. 1994 ChunkList* list = free_chunks(index); 1995 assert(list->size() == chunk->word_size(), "Wrong chunk type."); 1996 list->return_chunk_at_head(chunk); 1997 log_trace(gc, metaspace, freelist)("returned one %s chunk at " PTR_FORMAT " to freelist.", 1998 chunk_size_name(index), p2i(chunk)); 1999 } else { 2000 // Return humongous chunk to dictionary. 2001 assert(chunk->word_size() > free_chunks(MediumIndex)->size(), "Wrong chunk type."); 2002 assert(chunk->word_size() % free_chunks(SpecializedIndex)->size() == 0, 2003 "Humongous chunk has wrong alignment."); 2004 _humongous_dictionary.return_chunk(chunk); 2005 log_trace(gc, metaspace, freelist)("returned one %s chunk at " PTR_FORMAT " (word size " SIZE_FORMAT ") to freelist.", 2006 chunk_size_name(index), p2i(chunk), chunk->word_size()); 2007 } 2008 chunk->container()->dec_container_count(); 2009 DEBUG_ONLY(chunk->set_is_tagged_free(true);) 2010 2011 // Chunk has been added; update counters. 2012 account_for_added_chunk(chunk); 2013 2014 } 2015 2016 void ChunkManager::return_chunk_list(ChunkIndex index, Metachunk* chunks) { 2017 index_bounds_check(index); 2018 if (chunks == NULL) { 2019 return; 2020 } 2021 LogTarget(Trace, gc, metaspace, freelist) log; 2022 if (log.is_enabled()) { // tracing 2023 log.print("returning list of %s chunks...", chunk_size_name(index)); 2024 } 2025 unsigned num_chunks_returned = 0; 2026 size_t size_chunks_returned = 0; 2027 Metachunk* cur = chunks; 2028 while (cur != NULL) { 2029 // Capture the next link before it is changed 2030 // by the call to return_chunk_at_head(); 2031 Metachunk* next = cur->next(); 2032 if (log.is_enabled()) { // tracing 2033 num_chunks_returned ++; 2034 size_chunks_returned += cur->word_size(); 2035 } 2036 return_single_chunk(index, cur); 2037 cur = next; 2038 } 2039 if (log.is_enabled()) { // tracing 2040 log.print("returned %u %s chunks to freelist, total word size " SIZE_FORMAT ".", 2041 num_chunks_returned, chunk_size_name(index), size_chunks_returned); 2042 if (index != HumongousIndex) { 2043 log.print("updated freelist count: " SIZE_FORMAT ".", free_chunks(index)->size()); 2044 } else { 2045 log.print("updated dictionary count " SIZE_FORMAT ".", _humongous_dictionary.total_count()); 2046 } 2047 } 2048 } 2049 2050 void ChunkManager::print_on(outputStream* out) const { 2051 const_cast<ChunkManager *>(this)->humongous_dictionary()->report_statistics(out); 2052 } 2053 2054 // SpaceManager methods 2055 2056 size_t SpaceManager::adjust_initial_chunk_size(size_t requested, bool is_class_space) { 2057 size_t chunk_sizes[] = { 2058 specialized_chunk_size(is_class_space), 2059 small_chunk_size(is_class_space), 2060 medium_chunk_size(is_class_space) 2061 }; 2062 2063 // Adjust up to one of the fixed chunk sizes ... 2064 for (size_t i = 0; i < ARRAY_SIZE(chunk_sizes); i++) { 2065 if (requested <= chunk_sizes[i]) { 2066 return chunk_sizes[i]; 2067 } 2068 } 2069 2070 // ... or return the size as a humongous chunk. 2071 return requested; 2072 } 2073 2074 size_t SpaceManager::adjust_initial_chunk_size(size_t requested) const { 2075 return adjust_initial_chunk_size(requested, is_class()); 2076 } 2077 2078 size_t SpaceManager::get_initial_chunk_size(Metaspace::MetaspaceType type) const { 2079 size_t requested; 2080 2081 if (is_class()) { 2082 switch (type) { 2083 case Metaspace::BootMetaspaceType: requested = Metaspace::first_class_chunk_word_size(); break; 2084 case Metaspace::ROMetaspaceType: requested = ClassSpecializedChunk; break; 2085 case Metaspace::ReadWriteMetaspaceType: requested = ClassSpecializedChunk; break; 2086 case Metaspace::AnonymousMetaspaceType: requested = ClassSpecializedChunk; break; 2087 case Metaspace::ReflectionMetaspaceType: requested = ClassSpecializedChunk; break; 2088 default: requested = ClassSmallChunk; break; 2089 } 2090 } else { 2091 switch (type) { 2092 case Metaspace::BootMetaspaceType: requested = Metaspace::first_chunk_word_size(); break; 2093 case Metaspace::ROMetaspaceType: requested = SharedReadOnlySize / wordSize; break; 2094 case Metaspace::ReadWriteMetaspaceType: requested = SharedReadWriteSize / wordSize; break; 2095 case Metaspace::AnonymousMetaspaceType: requested = SpecializedChunk; break; 2096 case Metaspace::ReflectionMetaspaceType: requested = SpecializedChunk; break; 2097 default: requested = SmallChunk; break; 2098 } 2099 } 2100 2101 // Adjust to one of the fixed chunk sizes (unless humongous) 2102 const size_t adjusted = adjust_initial_chunk_size(requested); 2103 2104 assert(adjusted != 0, "Incorrect initial chunk size. Requested: " 2105 SIZE_FORMAT " adjusted: " SIZE_FORMAT, requested, adjusted); 2106 2107 return adjusted; 2108 } 2109 2110 size_t SpaceManager::sum_free_in_chunks_in_use() const { 2111 MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag); 2112 size_t free = 0; 2113 for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) { 2114 Metachunk* chunk = chunks_in_use(i); 2115 while (chunk != NULL) { 2116 free += chunk->free_word_size(); 2117 chunk = chunk->next(); 2118 } 2119 } 2120 return free; 2121 } 2122 2123 size_t SpaceManager::sum_waste_in_chunks_in_use() const { 2124 MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag); 2125 size_t result = 0; 2126 for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) { 2127 result += sum_waste_in_chunks_in_use(i); 2128 } 2129 2130 return result; 2131 } 2132 2133 size_t SpaceManager::sum_waste_in_chunks_in_use(ChunkIndex index) const { 2134 size_t result = 0; 2135 Metachunk* chunk = chunks_in_use(index); 2136 // Count the free space in all the chunk but not the 2137 // current chunk from which allocations are still being done. 2138 while (chunk != NULL) { 2139 if (chunk != current_chunk()) { 2140 result += chunk->free_word_size(); 2141 } 2142 chunk = chunk->next(); 2143 } 2144 return result; 2145 } 2146 2147 size_t SpaceManager::sum_capacity_in_chunks_in_use() const { 2148 // For CMS use "allocated_chunks_words()" which does not need the 2149 // Metaspace lock. For the other collectors sum over the 2150 // lists. Use both methods as a check that "allocated_chunks_words()" 2151 // is correct. That is, sum_capacity_in_chunks() is too expensive 2152 // to use in the product and allocated_chunks_words() should be used 2153 // but allow for checking that allocated_chunks_words() returns the same 2154 // value as sum_capacity_in_chunks_in_use() which is the definitive 2155 // answer. 2156 if (UseConcMarkSweepGC) { 2157 return allocated_chunks_words(); 2158 } else { 2159 MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag); 2160 size_t sum = 0; 2161 for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) { 2162 Metachunk* chunk = chunks_in_use(i); 2163 while (chunk != NULL) { 2164 sum += chunk->word_size(); 2165 chunk = chunk->next(); 2166 } 2167 } 2168 return sum; 2169 } 2170 } 2171 2172 size_t SpaceManager::sum_count_in_chunks_in_use() { 2173 size_t count = 0; 2174 for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) { 2175 count = count + sum_count_in_chunks_in_use(i); 2176 } 2177 2178 return count; 2179 } 2180 2181 size_t SpaceManager::sum_count_in_chunks_in_use(ChunkIndex i) { 2182 size_t count = 0; 2183 Metachunk* chunk = chunks_in_use(i); 2184 while (chunk != NULL) { 2185 count++; 2186 chunk = chunk->next(); 2187 } 2188 return count; 2189 } 2190 2191 2192 size_t SpaceManager::sum_used_in_chunks_in_use() const { 2193 MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag); 2194 size_t used = 0; 2195 for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) { 2196 Metachunk* chunk = chunks_in_use(i); 2197 while (chunk != NULL) { 2198 used += chunk->used_word_size(); 2199 chunk = chunk->next(); 2200 } 2201 } 2202 return used; 2203 } 2204 2205 void SpaceManager::locked_print_chunks_in_use_on(outputStream* st) const { 2206 2207 for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) { 2208 Metachunk* chunk = chunks_in_use(i); 2209 st->print("SpaceManager: %s " PTR_FORMAT, 2210 chunk_size_name(i), p2i(chunk)); 2211 if (chunk != NULL) { 2212 st->print_cr(" free " SIZE_FORMAT, 2213 chunk->free_word_size()); 2214 } else { 2215 st->cr(); 2216 } 2217 } 2218 2219 chunk_manager()->locked_print_free_chunks(st); 2220 chunk_manager()->locked_print_sum_free_chunks(st); 2221 } 2222 2223 size_t SpaceManager::calc_chunk_size(size_t word_size) { 2224 2225 // Decide between a small chunk and a medium chunk. Up to 2226 // _small_chunk_limit small chunks can be allocated. 2227 // After that a medium chunk is preferred. 2228 size_t chunk_word_size; 2229 if (chunks_in_use(MediumIndex) == NULL && 2230 sum_count_in_chunks_in_use(SmallIndex) < _small_chunk_limit) { 2231 chunk_word_size = (size_t) small_chunk_size(); 2232 if (word_size + Metachunk::overhead() > small_chunk_size()) { 2233 chunk_word_size = medium_chunk_size(); 2234 } 2235 } else { 2236 chunk_word_size = medium_chunk_size(); 2237 } 2238 2239 // Might still need a humongous chunk. Enforce 2240 // humongous allocations sizes to be aligned up to 2241 // the smallest chunk size. 2242 size_t if_humongous_sized_chunk = 2243 align_size_up(word_size + Metachunk::overhead(), 2244 smallest_chunk_size()); 2245 chunk_word_size = 2246 MAX2((size_t) chunk_word_size, if_humongous_sized_chunk); 2247 2248 assert(!SpaceManager::is_humongous(word_size) || 2249 chunk_word_size == if_humongous_sized_chunk, 2250 "Size calculation is wrong, word_size " SIZE_FORMAT 2251 " chunk_word_size " SIZE_FORMAT, 2252 word_size, chunk_word_size); 2253 Log(gc, metaspace, alloc) log; 2254 if (log.is_debug() && SpaceManager::is_humongous(word_size)) { 2255 log.debug("Metadata humongous allocation:"); 2256 log.debug(" word_size " PTR_FORMAT, word_size); 2257 log.debug(" chunk_word_size " PTR_FORMAT, chunk_word_size); 2258 log.debug(" chunk overhead " PTR_FORMAT, Metachunk::overhead()); 2259 } 2260 return chunk_word_size; 2261 } 2262 2263 void SpaceManager::track_metaspace_memory_usage() { 2264 if (is_init_completed()) { 2265 if (is_class()) { 2266 MemoryService::track_compressed_class_memory_usage(); 2267 } 2268 MemoryService::track_metaspace_memory_usage(); 2269 } 2270 } 2271 2272 MetaWord* SpaceManager::grow_and_allocate(size_t word_size) { 2273 assert(vs_list()->current_virtual_space() != NULL, 2274 "Should have been set"); 2275 assert(current_chunk() == NULL || 2276 current_chunk()->allocate(word_size) == NULL, 2277 "Don't need to expand"); 2278 MutexLockerEx cl(SpaceManager::expand_lock(), Mutex::_no_safepoint_check_flag); 2279 2280 if (log_is_enabled(Trace, gc, metaspace, freelist)) { 2281 size_t words_left = 0; 2282 size_t words_used = 0; 2283 if (current_chunk() != NULL) { 2284 words_left = current_chunk()->free_word_size(); 2285 words_used = current_chunk()->used_word_size(); 2286 } 2287 log_trace(gc, metaspace, freelist)("SpaceManager::grow_and_allocate for " SIZE_FORMAT " words " SIZE_FORMAT " words used " SIZE_FORMAT " words left", 2288 word_size, words_used, words_left); 2289 } 2290 2291 // Get another chunk 2292 size_t chunk_word_size = calc_chunk_size(word_size); 2293 Metachunk* next = get_new_chunk(chunk_word_size); 2294 2295 MetaWord* mem = NULL; 2296 2297 // If a chunk was available, add it to the in-use chunk list 2298 // and do an allocation from it. 2299 if (next != NULL) { 2300 // Add to this manager's list of chunks in use. 2301 add_chunk(next, false); 2302 mem = next->allocate(word_size); 2303 } 2304 2305 // Track metaspace memory usage statistic. 2306 track_metaspace_memory_usage(); 2307 2308 return mem; 2309 } 2310 2311 void SpaceManager::print_on(outputStream* st) const { 2312 2313 for (ChunkIndex i = ZeroIndex; 2314 i < NumberOfInUseLists ; 2315 i = next_chunk_index(i) ) { 2316 st->print_cr(" chunks_in_use " PTR_FORMAT " chunk size " SIZE_FORMAT, 2317 p2i(chunks_in_use(i)), 2318 chunks_in_use(i) == NULL ? 0 : chunks_in_use(i)->word_size()); 2319 } 2320 st->print_cr(" waste: Small " SIZE_FORMAT " Medium " SIZE_FORMAT 2321 " Humongous " SIZE_FORMAT, 2322 sum_waste_in_chunks_in_use(SmallIndex), 2323 sum_waste_in_chunks_in_use(MediumIndex), 2324 sum_waste_in_chunks_in_use(HumongousIndex)); 2325 // block free lists 2326 if (block_freelists() != NULL) { 2327 st->print_cr("total in block free lists " SIZE_FORMAT, 2328 block_freelists()->total_size()); 2329 } 2330 } 2331 2332 SpaceManager::SpaceManager(Metaspace::MetadataType mdtype, 2333 Mutex* lock) : 2334 _mdtype(mdtype), 2335 _allocated_blocks_words(0), 2336 _allocated_chunks_words(0), 2337 _allocated_chunks_count(0), 2338 _block_freelists(NULL), 2339 _lock(lock) 2340 { 2341 initialize(); 2342 } 2343 2344 void SpaceManager::inc_size_metrics(size_t words) { 2345 assert_lock_strong(SpaceManager::expand_lock()); 2346 // Total of allocated Metachunks and allocated Metachunks count 2347 // for each SpaceManager 2348 _allocated_chunks_words = _allocated_chunks_words + words; 2349 _allocated_chunks_count++; 2350 // Global total of capacity in allocated Metachunks 2351 MetaspaceAux::inc_capacity(mdtype(), words); 2352 // Global total of allocated Metablocks. 2353 // used_words_slow() includes the overhead in each 2354 // Metachunk so include it in the used when the 2355 // Metachunk is first added (so only added once per 2356 // Metachunk). 2357 MetaspaceAux::inc_used(mdtype(), Metachunk::overhead()); 2358 } 2359 2360 void SpaceManager::inc_used_metrics(size_t words) { 2361 // Add to the per SpaceManager total 2362 Atomic::add_ptr(words, &_allocated_blocks_words); 2363 // Add to the global total 2364 MetaspaceAux::inc_used(mdtype(), words); 2365 } 2366 2367 void SpaceManager::dec_total_from_size_metrics() { 2368 MetaspaceAux::dec_capacity(mdtype(), allocated_chunks_words()); 2369 MetaspaceAux::dec_used(mdtype(), allocated_blocks_words()); 2370 // Also deduct the overhead per Metachunk 2371 MetaspaceAux::dec_used(mdtype(), allocated_chunks_count() * Metachunk::overhead()); 2372 } 2373 2374 void SpaceManager::initialize() { 2375 Metadebug::init_allocation_fail_alot_count(); 2376 for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) { 2377 _chunks_in_use[i] = NULL; 2378 } 2379 _current_chunk = NULL; 2380 log_trace(gc, metaspace, freelist)("SpaceManager(): " PTR_FORMAT, p2i(this)); 2381 } 2382 2383 SpaceManager::~SpaceManager() { 2384 // This call this->_lock which can't be done while holding expand_lock() 2385 assert(sum_capacity_in_chunks_in_use() == allocated_chunks_words(), 2386 "sum_capacity_in_chunks_in_use() " SIZE_FORMAT 2387 " allocated_chunks_words() " SIZE_FORMAT, 2388 sum_capacity_in_chunks_in_use(), allocated_chunks_words()); 2389 2390 MutexLockerEx fcl(SpaceManager::expand_lock(), 2391 Mutex::_no_safepoint_check_flag); 2392 2393 chunk_manager()->slow_locked_verify(); 2394 2395 dec_total_from_size_metrics(); 2396 2397 Log(gc, metaspace, freelist) log; 2398 if (log.is_trace()) { 2399 log.trace("~SpaceManager(): " PTR_FORMAT, p2i(this)); 2400 ResourceMark rm; 2401 locked_print_chunks_in_use_on(log.trace_stream()); 2402 if (block_freelists() != NULL) { 2403 block_freelists()->print_on(log.trace_stream()); 2404 } 2405 } 2406 2407 // Add all the chunks in use by this space manager 2408 // to the global list of free chunks. 2409 2410 // Follow each list of chunks-in-use and add them to the 2411 // free lists. Each list is NULL terminated. 2412 2413 for (ChunkIndex i = ZeroIndex; i <= HumongousIndex; i = next_chunk_index(i)) { 2414 Metachunk* chunks = chunks_in_use(i); 2415 chunk_manager()->return_chunk_list(i, chunks); 2416 set_chunks_in_use(i, NULL); 2417 } 2418 2419 chunk_manager()->slow_locked_verify(); 2420 2421 if (_block_freelists != NULL) { 2422 delete _block_freelists; 2423 } 2424 } 2425 2426 void SpaceManager::deallocate(MetaWord* p, size_t word_size) { 2427 assert_lock_strong(_lock); 2428 // Allocations and deallocations are in raw_word_size 2429 size_t raw_word_size = get_allocation_word_size(word_size); 2430 // Lazily create a block_freelist 2431 if (block_freelists() == NULL) { 2432 _block_freelists = new BlockFreelist(); 2433 } 2434 block_freelists()->return_block(p, raw_word_size); 2435 } 2436 2437 // Adds a chunk to the list of chunks in use. 2438 void SpaceManager::add_chunk(Metachunk* new_chunk, bool make_current) { 2439 2440 assert(new_chunk != NULL, "Should not be NULL"); 2441 assert(new_chunk->next() == NULL, "Should not be on a list"); 2442 2443 new_chunk->reset_empty(); 2444 2445 // Find the correct list and and set the current 2446 // chunk for that list. 2447 ChunkIndex index = chunk_manager()->list_index(new_chunk->word_size()); 2448 2449 if (index != HumongousIndex) { 2450 retire_current_chunk(); 2451 set_current_chunk(new_chunk); 2452 new_chunk->set_next(chunks_in_use(index)); 2453 set_chunks_in_use(index, new_chunk); 2454 } else { 2455 // For null class loader data and DumpSharedSpaces, the first chunk isn't 2456 // small, so small will be null. Link this first chunk as the current 2457 // chunk. 2458 if (make_current) { 2459 // Set as the current chunk but otherwise treat as a humongous chunk. 2460 set_current_chunk(new_chunk); 2461 } 2462 // Link at head. The _current_chunk only points to a humongous chunk for 2463 // the null class loader metaspace (class and data virtual space managers) 2464 // any humongous chunks so will not point to the tail 2465 // of the humongous chunks list. 2466 new_chunk->set_next(chunks_in_use(HumongousIndex)); 2467 set_chunks_in_use(HumongousIndex, new_chunk); 2468 2469 assert(new_chunk->word_size() > medium_chunk_size(), "List inconsistency"); 2470 } 2471 2472 // Add to the running sum of capacity 2473 inc_size_metrics(new_chunk->word_size()); 2474 2475 assert(new_chunk->is_empty(), "Not ready for reuse"); 2476 Log(gc, metaspace, freelist) log; 2477 if (log.is_trace()) { 2478 log.trace("SpaceManager::add_chunk: " SIZE_FORMAT ") ", sum_count_in_chunks_in_use()); 2479 ResourceMark rm; 2480 outputStream* out = log.trace_stream(); 2481 new_chunk->print_on(out); 2482 chunk_manager()->locked_print_free_chunks(out); 2483 } 2484 } 2485 2486 void SpaceManager::retire_current_chunk() { 2487 if (current_chunk() != NULL) { 2488 size_t remaining_words = current_chunk()->free_word_size(); 2489 if (remaining_words >= BlockFreelist::min_dictionary_size()) { 2490 MetaWord* ptr = current_chunk()->allocate(remaining_words); 2491 deallocate(ptr, remaining_words); 2492 inc_used_metrics(remaining_words); 2493 } 2494 } 2495 } 2496 2497 Metachunk* SpaceManager::get_new_chunk(size_t chunk_word_size) { 2498 // Get a chunk from the chunk freelist 2499 Metachunk* next = chunk_manager()->chunk_freelist_allocate(chunk_word_size); 2500 2501 if (next == NULL) { 2502 next = vs_list()->get_new_chunk(chunk_word_size, 2503 medium_chunk_bunch()); 2504 } 2505 2506 Log(gc, metaspace, alloc) log; 2507 if (log.is_debug() && next != NULL && 2508 SpaceManager::is_humongous(next->word_size())) { 2509 log.debug(" new humongous chunk word size " PTR_FORMAT, next->word_size()); 2510 } 2511 2512 return next; 2513 } 2514 2515 /* 2516 * The policy is to allocate up to _small_chunk_limit small chunks 2517 * after which only medium chunks are allocated. This is done to 2518 * reduce fragmentation. In some cases, this can result in a lot 2519 * of small chunks being allocated to the point where it's not 2520 * possible to expand. If this happens, there may be no medium chunks 2521 * available and OOME would be thrown. Instead of doing that, 2522 * if the allocation request size fits in a small chunk, an attempt 2523 * will be made to allocate a small chunk. 2524 */ 2525 MetaWord* SpaceManager::get_small_chunk_and_allocate(size_t word_size) { 2526 size_t raw_word_size = get_allocation_word_size(word_size); 2527 2528 if (raw_word_size + Metachunk::overhead() > small_chunk_size()) { 2529 return NULL; 2530 } 2531 2532 MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag); 2533 MutexLockerEx cl1(expand_lock(), Mutex::_no_safepoint_check_flag); 2534 2535 Metachunk* chunk = chunk_manager()->chunk_freelist_allocate(small_chunk_size()); 2536 2537 MetaWord* mem = NULL; 2538 2539 if (chunk != NULL) { 2540 // Add chunk to the in-use chunk list and do an allocation from it. 2541 // Add to this manager's list of chunks in use. 2542 add_chunk(chunk, false); 2543 mem = chunk->allocate(raw_word_size); 2544 2545 inc_used_metrics(raw_word_size); 2546 2547 // Track metaspace memory usage statistic. 2548 track_metaspace_memory_usage(); 2549 } 2550 2551 return mem; 2552 } 2553 2554 MetaWord* SpaceManager::allocate(size_t word_size) { 2555 MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag); 2556 size_t raw_word_size = get_allocation_word_size(word_size); 2557 BlockFreelist* fl = block_freelists(); 2558 MetaWord* p = NULL; 2559 // Allocation from the dictionary is expensive in the sense that 2560 // the dictionary has to be searched for a size. Don't allocate 2561 // from the dictionary until it starts to get fat. Is this 2562 // a reasonable policy? Maybe an skinny dictionary is fast enough 2563 // for allocations. Do some profiling. JJJ 2564 if (fl != NULL && fl->total_size() > allocation_from_dictionary_limit) { 2565 p = fl->get_block(raw_word_size); 2566 } 2567 if (p == NULL) { 2568 p = allocate_work(raw_word_size); 2569 } 2570 2571 return p; 2572 } 2573 2574 // Returns the address of spaced allocated for "word_size". 2575 // This methods does not know about blocks (Metablocks) 2576 MetaWord* SpaceManager::allocate_work(size_t word_size) { 2577 assert_lock_strong(_lock); 2578 #ifdef ASSERT 2579 if (Metadebug::test_metadata_failure()) { 2580 return NULL; 2581 } 2582 #endif 2583 // Is there space in the current chunk? 2584 MetaWord* result = NULL; 2585 2586 // For DumpSharedSpaces, only allocate out of the current chunk which is 2587 // never null because we gave it the size we wanted. Caller reports out 2588 // of memory if this returns null. 2589 if (DumpSharedSpaces) { 2590 assert(current_chunk() != NULL, "should never happen"); 2591 inc_used_metrics(word_size); 2592 return current_chunk()->allocate(word_size); // caller handles null result 2593 } 2594 2595 if (current_chunk() != NULL) { 2596 result = current_chunk()->allocate(word_size); 2597 } 2598 2599 if (result == NULL) { 2600 result = grow_and_allocate(word_size); 2601 } 2602 2603 if (result != NULL) { 2604 inc_used_metrics(word_size); 2605 assert(result != (MetaWord*) chunks_in_use(MediumIndex), 2606 "Head of the list is being allocated"); 2607 } 2608 2609 return result; 2610 } 2611 2612 void SpaceManager::verify() { 2613 // If there are blocks in the dictionary, then 2614 // verification of chunks does not work since 2615 // being in the dictionary alters a chunk. 2616 if (block_freelists() != NULL && block_freelists()->total_size() == 0) { 2617 for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) { 2618 Metachunk* curr = chunks_in_use(i); 2619 while (curr != NULL) { 2620 curr->verify(); 2621 verify_chunk_size(curr); 2622 curr = curr->next(); 2623 } 2624 } 2625 } 2626 } 2627 2628 void SpaceManager::verify_chunk_size(Metachunk* chunk) { 2629 assert(is_humongous(chunk->word_size()) || 2630 chunk->word_size() == medium_chunk_size() || 2631 chunk->word_size() == small_chunk_size() || 2632 chunk->word_size() == specialized_chunk_size(), 2633 "Chunk size is wrong"); 2634 return; 2635 } 2636 2637 #ifdef ASSERT 2638 void SpaceManager::verify_allocated_blocks_words() { 2639 // Verification is only guaranteed at a safepoint. 2640 assert(SafepointSynchronize::is_at_safepoint() || !Universe::is_fully_initialized(), 2641 "Verification can fail if the applications is running"); 2642 assert(allocated_blocks_words() == sum_used_in_chunks_in_use(), 2643 "allocation total is not consistent " SIZE_FORMAT 2644 " vs " SIZE_FORMAT, 2645 allocated_blocks_words(), sum_used_in_chunks_in_use()); 2646 } 2647 2648 #endif 2649 2650 void SpaceManager::dump(outputStream* const out) const { 2651 size_t curr_total = 0; 2652 size_t waste = 0; 2653 uint i = 0; 2654 size_t used = 0; 2655 size_t capacity = 0; 2656 2657 // Add up statistics for all chunks in this SpaceManager. 2658 for (ChunkIndex index = ZeroIndex; 2659 index < NumberOfInUseLists; 2660 index = next_chunk_index(index)) { 2661 for (Metachunk* curr = chunks_in_use(index); 2662 curr != NULL; 2663 curr = curr->next()) { 2664 out->print("%d) ", i++); 2665 curr->print_on(out); 2666 curr_total += curr->word_size(); 2667 used += curr->used_word_size(); 2668 capacity += curr->word_size(); 2669 waste += curr->free_word_size() + curr->overhead();; 2670 } 2671 } 2672 2673 if (log_is_enabled(Trace, gc, metaspace, freelist)) { 2674 if (block_freelists() != NULL) block_freelists()->print_on(out); 2675 } 2676 2677 size_t free = current_chunk() == NULL ? 0 : current_chunk()->free_word_size(); 2678 // Free space isn't wasted. 2679 waste -= free; 2680 2681 out->print_cr("total of all chunks " SIZE_FORMAT " used " SIZE_FORMAT 2682 " free " SIZE_FORMAT " capacity " SIZE_FORMAT 2683 " waste " SIZE_FORMAT, curr_total, used, free, capacity, waste); 2684 } 2685 2686 // MetaspaceAux 2687 2688 2689 size_t MetaspaceAux::_capacity_words[] = {0, 0}; 2690 size_t MetaspaceAux::_used_words[] = {0, 0}; 2691 2692 size_t MetaspaceAux::free_bytes(Metaspace::MetadataType mdtype) { 2693 VirtualSpaceList* list = Metaspace::get_space_list(mdtype); 2694 return list == NULL ? 0 : list->free_bytes(); 2695 } 2696 2697 size_t MetaspaceAux::free_bytes() { 2698 return free_bytes(Metaspace::ClassType) + free_bytes(Metaspace::NonClassType); 2699 } 2700 2701 void MetaspaceAux::dec_capacity(Metaspace::MetadataType mdtype, size_t words) { 2702 assert_lock_strong(SpaceManager::expand_lock()); 2703 assert(words <= capacity_words(mdtype), 2704 "About to decrement below 0: words " SIZE_FORMAT 2705 " is greater than _capacity_words[%u] " SIZE_FORMAT, 2706 words, mdtype, capacity_words(mdtype)); 2707 _capacity_words[mdtype] -= words; 2708 } 2709 2710 void MetaspaceAux::inc_capacity(Metaspace::MetadataType mdtype, size_t words) { 2711 assert_lock_strong(SpaceManager::expand_lock()); 2712 // Needs to be atomic 2713 _capacity_words[mdtype] += words; 2714 } 2715 2716 void MetaspaceAux::dec_used(Metaspace::MetadataType mdtype, size_t words) { 2717 assert(words <= used_words(mdtype), 2718 "About to decrement below 0: words " SIZE_FORMAT 2719 " is greater than _used_words[%u] " SIZE_FORMAT, 2720 words, mdtype, used_words(mdtype)); 2721 // For CMS deallocation of the Metaspaces occurs during the 2722 // sweep which is a concurrent phase. Protection by the expand_lock() 2723 // is not enough since allocation is on a per Metaspace basis 2724 // and protected by the Metaspace lock. 2725 jlong minus_words = (jlong) - (jlong) words; 2726 Atomic::add_ptr(minus_words, &_used_words[mdtype]); 2727 } 2728 2729 void MetaspaceAux::inc_used(Metaspace::MetadataType mdtype, size_t words) { 2730 // _used_words tracks allocations for 2731 // each piece of metadata. Those allocations are 2732 // generally done concurrently by different application 2733 // threads so must be done atomically. 2734 Atomic::add_ptr(words, &_used_words[mdtype]); 2735 } 2736 2737 size_t MetaspaceAux::used_bytes_slow(Metaspace::MetadataType mdtype) { 2738 size_t used = 0; 2739 ClassLoaderDataGraphMetaspaceIterator iter; 2740 while (iter.repeat()) { 2741 Metaspace* msp = iter.get_next(); 2742 // Sum allocated_blocks_words for each metaspace 2743 if (msp != NULL) { 2744 used += msp->used_words_slow(mdtype); 2745 } 2746 } 2747 return used * BytesPerWord; 2748 } 2749 2750 size_t MetaspaceAux::free_bytes_slow(Metaspace::MetadataType mdtype) { 2751 size_t free = 0; 2752 ClassLoaderDataGraphMetaspaceIterator iter; 2753 while (iter.repeat()) { 2754 Metaspace* msp = iter.get_next(); 2755 if (msp != NULL) { 2756 free += msp->free_words_slow(mdtype); 2757 } 2758 } 2759 return free * BytesPerWord; 2760 } 2761 2762 size_t MetaspaceAux::capacity_bytes_slow(Metaspace::MetadataType mdtype) { 2763 if ((mdtype == Metaspace::ClassType) && !Metaspace::using_class_space()) { 2764 return 0; 2765 } 2766 // Don't count the space in the freelists. That space will be 2767 // added to the capacity calculation as needed. 2768 size_t capacity = 0; 2769 ClassLoaderDataGraphMetaspaceIterator iter; 2770 while (iter.repeat()) { 2771 Metaspace* msp = iter.get_next(); 2772 if (msp != NULL) { 2773 capacity += msp->capacity_words_slow(mdtype); 2774 } 2775 } 2776 return capacity * BytesPerWord; 2777 } 2778 2779 size_t MetaspaceAux::capacity_bytes_slow() { 2780 #ifdef PRODUCT 2781 // Use capacity_bytes() in PRODUCT instead of this function. 2782 guarantee(false, "Should not call capacity_bytes_slow() in the PRODUCT"); 2783 #endif 2784 size_t class_capacity = capacity_bytes_slow(Metaspace::ClassType); 2785 size_t non_class_capacity = capacity_bytes_slow(Metaspace::NonClassType); 2786 assert(capacity_bytes() == class_capacity + non_class_capacity, 2787 "bad accounting: capacity_bytes() " SIZE_FORMAT 2788 " class_capacity + non_class_capacity " SIZE_FORMAT 2789 " class_capacity " SIZE_FORMAT " non_class_capacity " SIZE_FORMAT, 2790 capacity_bytes(), class_capacity + non_class_capacity, 2791 class_capacity, non_class_capacity); 2792 2793 return class_capacity + non_class_capacity; 2794 } 2795 2796 size_t MetaspaceAux::reserved_bytes(Metaspace::MetadataType mdtype) { 2797 VirtualSpaceList* list = Metaspace::get_space_list(mdtype); 2798 return list == NULL ? 0 : list->reserved_bytes(); 2799 } 2800 2801 size_t MetaspaceAux::committed_bytes(Metaspace::MetadataType mdtype) { 2802 VirtualSpaceList* list = Metaspace::get_space_list(mdtype); 2803 return list == NULL ? 0 : list->committed_bytes(); 2804 } 2805 2806 size_t MetaspaceAux::min_chunk_size_words() { return Metaspace::first_chunk_word_size(); } 2807 2808 size_t MetaspaceAux::free_chunks_total_words(Metaspace::MetadataType mdtype) { 2809 ChunkManager* chunk_manager = Metaspace::get_chunk_manager(mdtype); 2810 if (chunk_manager == NULL) { 2811 return 0; 2812 } 2813 chunk_manager->slow_verify(); 2814 return chunk_manager->free_chunks_total_words(); 2815 } 2816 2817 size_t MetaspaceAux::free_chunks_total_bytes(Metaspace::MetadataType mdtype) { 2818 return free_chunks_total_words(mdtype) * BytesPerWord; 2819 } 2820 2821 size_t MetaspaceAux::free_chunks_total_words() { 2822 return free_chunks_total_words(Metaspace::ClassType) + 2823 free_chunks_total_words(Metaspace::NonClassType); 2824 } 2825 2826 size_t MetaspaceAux::free_chunks_total_bytes() { 2827 return free_chunks_total_words() * BytesPerWord; 2828 } 2829 2830 bool MetaspaceAux::has_chunk_free_list(Metaspace::MetadataType mdtype) { 2831 return Metaspace::get_chunk_manager(mdtype) != NULL; 2832 } 2833 2834 MetaspaceChunkFreeListSummary MetaspaceAux::chunk_free_list_summary(Metaspace::MetadataType mdtype) { 2835 if (!has_chunk_free_list(mdtype)) { 2836 return MetaspaceChunkFreeListSummary(); 2837 } 2838 2839 const ChunkManager* cm = Metaspace::get_chunk_manager(mdtype); 2840 return cm->chunk_free_list_summary(); 2841 } 2842 2843 void MetaspaceAux::print_metaspace_change(size_t prev_metadata_used) { 2844 log_info(gc, metaspace)("Metaspace: " SIZE_FORMAT "K->" SIZE_FORMAT "K(" SIZE_FORMAT "K)", 2845 prev_metadata_used/K, used_bytes()/K, reserved_bytes()/K); 2846 } 2847 2848 void MetaspaceAux::print_on(outputStream* out) { 2849 Metaspace::MetadataType nct = Metaspace::NonClassType; 2850 2851 out->print_cr(" Metaspace " 2852 "used " SIZE_FORMAT "K, " 2853 "capacity " SIZE_FORMAT "K, " 2854 "committed " SIZE_FORMAT "K, " 2855 "reserved " SIZE_FORMAT "K", 2856 used_bytes()/K, 2857 capacity_bytes()/K, 2858 committed_bytes()/K, 2859 reserved_bytes()/K); 2860 2861 if (Metaspace::using_class_space()) { 2862 Metaspace::MetadataType ct = Metaspace::ClassType; 2863 out->print_cr(" class space " 2864 "used " SIZE_FORMAT "K, " 2865 "capacity " SIZE_FORMAT "K, " 2866 "committed " SIZE_FORMAT "K, " 2867 "reserved " SIZE_FORMAT "K", 2868 used_bytes(ct)/K, 2869 capacity_bytes(ct)/K, 2870 committed_bytes(ct)/K, 2871 reserved_bytes(ct)/K); 2872 } 2873 } 2874 2875 // Print information for class space and data space separately. 2876 // This is almost the same as above. 2877 void MetaspaceAux::print_on(outputStream* out, Metaspace::MetadataType mdtype) { 2878 size_t free_chunks_capacity_bytes = free_chunks_total_bytes(mdtype); 2879 size_t capacity_bytes = capacity_bytes_slow(mdtype); 2880 size_t used_bytes = used_bytes_slow(mdtype); 2881 size_t free_bytes = free_bytes_slow(mdtype); 2882 size_t used_and_free = used_bytes + free_bytes + 2883 free_chunks_capacity_bytes; 2884 out->print_cr(" Chunk accounting: used in chunks " SIZE_FORMAT 2885 "K + unused in chunks " SIZE_FORMAT "K + " 2886 " capacity in free chunks " SIZE_FORMAT "K = " SIZE_FORMAT 2887 "K capacity in allocated chunks " SIZE_FORMAT "K", 2888 used_bytes / K, 2889 free_bytes / K, 2890 free_chunks_capacity_bytes / K, 2891 used_and_free / K, 2892 capacity_bytes / K); 2893 // Accounting can only be correct if we got the values during a safepoint 2894 assert(!SafepointSynchronize::is_at_safepoint() || used_and_free == capacity_bytes, "Accounting is wrong"); 2895 } 2896 2897 // Print total fragmentation for class metaspaces 2898 void MetaspaceAux::print_class_waste(outputStream* out) { 2899 assert(Metaspace::using_class_space(), "class metaspace not used"); 2900 size_t cls_specialized_waste = 0, cls_small_waste = 0, cls_medium_waste = 0; 2901 size_t cls_specialized_count = 0, cls_small_count = 0, cls_medium_count = 0, cls_humongous_count = 0; 2902 ClassLoaderDataGraphMetaspaceIterator iter; 2903 while (iter.repeat()) { 2904 Metaspace* msp = iter.get_next(); 2905 if (msp != NULL) { 2906 cls_specialized_waste += msp->class_vsm()->sum_waste_in_chunks_in_use(SpecializedIndex); 2907 cls_specialized_count += msp->class_vsm()->sum_count_in_chunks_in_use(SpecializedIndex); 2908 cls_small_waste += msp->class_vsm()->sum_waste_in_chunks_in_use(SmallIndex); 2909 cls_small_count += msp->class_vsm()->sum_count_in_chunks_in_use(SmallIndex); 2910 cls_medium_waste += msp->class_vsm()->sum_waste_in_chunks_in_use(MediumIndex); 2911 cls_medium_count += msp->class_vsm()->sum_count_in_chunks_in_use(MediumIndex); 2912 cls_humongous_count += msp->class_vsm()->sum_count_in_chunks_in_use(HumongousIndex); 2913 } 2914 } 2915 out->print_cr(" class: " SIZE_FORMAT " specialized(s) " SIZE_FORMAT ", " 2916 SIZE_FORMAT " small(s) " SIZE_FORMAT ", " 2917 SIZE_FORMAT " medium(s) " SIZE_FORMAT ", " 2918 "large count " SIZE_FORMAT, 2919 cls_specialized_count, cls_specialized_waste, 2920 cls_small_count, cls_small_waste, 2921 cls_medium_count, cls_medium_waste, cls_humongous_count); 2922 } 2923 2924 // Print total fragmentation for data and class metaspaces separately 2925 void MetaspaceAux::print_waste(outputStream* out) { 2926 size_t specialized_waste = 0, small_waste = 0, medium_waste = 0; 2927 size_t specialized_count = 0, small_count = 0, medium_count = 0, humongous_count = 0; 2928 2929 ClassLoaderDataGraphMetaspaceIterator iter; 2930 while (iter.repeat()) { 2931 Metaspace* msp = iter.get_next(); 2932 if (msp != NULL) { 2933 specialized_waste += msp->vsm()->sum_waste_in_chunks_in_use(SpecializedIndex); 2934 specialized_count += msp->vsm()->sum_count_in_chunks_in_use(SpecializedIndex); 2935 small_waste += msp->vsm()->sum_waste_in_chunks_in_use(SmallIndex); 2936 small_count += msp->vsm()->sum_count_in_chunks_in_use(SmallIndex); 2937 medium_waste += msp->vsm()->sum_waste_in_chunks_in_use(MediumIndex); 2938 medium_count += msp->vsm()->sum_count_in_chunks_in_use(MediumIndex); 2939 humongous_count += msp->vsm()->sum_count_in_chunks_in_use(HumongousIndex); 2940 } 2941 } 2942 out->print_cr("Total fragmentation waste (words) doesn't count free space"); 2943 out->print_cr(" data: " SIZE_FORMAT " specialized(s) " SIZE_FORMAT ", " 2944 SIZE_FORMAT " small(s) " SIZE_FORMAT ", " 2945 SIZE_FORMAT " medium(s) " SIZE_FORMAT ", " 2946 "large count " SIZE_FORMAT, 2947 specialized_count, specialized_waste, small_count, 2948 small_waste, medium_count, medium_waste, humongous_count); 2949 if (Metaspace::using_class_space()) { 2950 print_class_waste(out); 2951 } 2952 } 2953 2954 // Dump global metaspace things from the end of ClassLoaderDataGraph 2955 void MetaspaceAux::dump(outputStream* out) { 2956 out->print_cr("All Metaspace:"); 2957 out->print("data space: "); print_on(out, Metaspace::NonClassType); 2958 out->print("class space: "); print_on(out, Metaspace::ClassType); 2959 print_waste(out); 2960 } 2961 2962 void MetaspaceAux::verify_free_chunks() { 2963 Metaspace::chunk_manager_metadata()->verify(); 2964 if (Metaspace::using_class_space()) { 2965 Metaspace::chunk_manager_class()->verify(); 2966 } 2967 } 2968 2969 void MetaspaceAux::verify_capacity() { 2970 #ifdef ASSERT 2971 size_t running_sum_capacity_bytes = capacity_bytes(); 2972 // For purposes of the running sum of capacity, verify against capacity 2973 size_t capacity_in_use_bytes = capacity_bytes_slow(); 2974 assert(running_sum_capacity_bytes == capacity_in_use_bytes, 2975 "capacity_words() * BytesPerWord " SIZE_FORMAT 2976 " capacity_bytes_slow()" SIZE_FORMAT, 2977 running_sum_capacity_bytes, capacity_in_use_bytes); 2978 for (Metaspace::MetadataType i = Metaspace::ClassType; 2979 i < Metaspace:: MetadataTypeCount; 2980 i = (Metaspace::MetadataType)(i + 1)) { 2981 size_t capacity_in_use_bytes = capacity_bytes_slow(i); 2982 assert(capacity_bytes(i) == capacity_in_use_bytes, 2983 "capacity_bytes(%u) " SIZE_FORMAT 2984 " capacity_bytes_slow(%u)" SIZE_FORMAT, 2985 i, capacity_bytes(i), i, capacity_in_use_bytes); 2986 } 2987 #endif 2988 } 2989 2990 void MetaspaceAux::verify_used() { 2991 #ifdef ASSERT 2992 size_t running_sum_used_bytes = used_bytes(); 2993 // For purposes of the running sum of used, verify against used 2994 size_t used_in_use_bytes = used_bytes_slow(); 2995 assert(used_bytes() == used_in_use_bytes, 2996 "used_bytes() " SIZE_FORMAT 2997 " used_bytes_slow()" SIZE_FORMAT, 2998 used_bytes(), used_in_use_bytes); 2999 for (Metaspace::MetadataType i = Metaspace::ClassType; 3000 i < Metaspace:: MetadataTypeCount; 3001 i = (Metaspace::MetadataType)(i + 1)) { 3002 size_t used_in_use_bytes = used_bytes_slow(i); 3003 assert(used_bytes(i) == used_in_use_bytes, 3004 "used_bytes(%u) " SIZE_FORMAT 3005 " used_bytes_slow(%u)" SIZE_FORMAT, 3006 i, used_bytes(i), i, used_in_use_bytes); 3007 } 3008 #endif 3009 } 3010 3011 void MetaspaceAux::verify_metrics() { 3012 verify_capacity(); 3013 verify_used(); 3014 } 3015 3016 3017 // Metaspace methods 3018 3019 size_t Metaspace::_first_chunk_word_size = 0; 3020 size_t Metaspace::_first_class_chunk_word_size = 0; 3021 3022 size_t Metaspace::_commit_alignment = 0; 3023 size_t Metaspace::_reserve_alignment = 0; 3024 3025 Metaspace::Metaspace(Mutex* lock, MetaspaceType type) { 3026 initialize(lock, type); 3027 } 3028 3029 Metaspace::~Metaspace() { 3030 delete _vsm; 3031 if (using_class_space()) { 3032 delete _class_vsm; 3033 } 3034 } 3035 3036 VirtualSpaceList* Metaspace::_space_list = NULL; 3037 VirtualSpaceList* Metaspace::_class_space_list = NULL; 3038 3039 ChunkManager* Metaspace::_chunk_manager_metadata = NULL; 3040 ChunkManager* Metaspace::_chunk_manager_class = NULL; 3041 3042 #define VIRTUALSPACEMULTIPLIER 2 3043 3044 #ifdef _LP64 3045 static const uint64_t UnscaledClassSpaceMax = (uint64_t(max_juint) + 1); 3046 3047 void Metaspace::set_narrow_klass_base_and_shift(address metaspace_base, address cds_base) { 3048 // Figure out the narrow_klass_base and the narrow_klass_shift. The 3049 // narrow_klass_base is the lower of the metaspace base and the cds base 3050 // (if cds is enabled). The narrow_klass_shift depends on the distance 3051 // between the lower base and higher address. 3052 address lower_base; 3053 address higher_address; 3054 #if INCLUDE_CDS 3055 if (UseSharedSpaces) { 3056 higher_address = MAX2((address)(cds_base + FileMapInfo::shared_spaces_size()), 3057 (address)(metaspace_base + compressed_class_space_size())); 3058 lower_base = MIN2(metaspace_base, cds_base); 3059 } else 3060 #endif 3061 { 3062 higher_address = metaspace_base + compressed_class_space_size(); 3063 lower_base = metaspace_base; 3064 3065 uint64_t klass_encoding_max = UnscaledClassSpaceMax << LogKlassAlignmentInBytes; 3066 // If compressed class space fits in lower 32G, we don't need a base. 3067 if (higher_address <= (address)klass_encoding_max) { 3068 lower_base = 0; // Effectively lower base is zero. 3069 } 3070 } 3071 3072 Universe::set_narrow_klass_base(lower_base); 3073 3074 if ((uint64_t)(higher_address - lower_base) <= UnscaledClassSpaceMax) { 3075 Universe::set_narrow_klass_shift(0); 3076 } else { 3077 assert(!UseSharedSpaces, "Cannot shift with UseSharedSpaces"); 3078 Universe::set_narrow_klass_shift(LogKlassAlignmentInBytes); 3079 } 3080 AOTLoader::set_narrow_klass_shift(); 3081 } 3082 3083 #if INCLUDE_CDS 3084 // Return TRUE if the specified metaspace_base and cds_base are close enough 3085 // to work with compressed klass pointers. 3086 bool Metaspace::can_use_cds_with_metaspace_addr(char* metaspace_base, address cds_base) { 3087 assert(cds_base != 0 && UseSharedSpaces, "Only use with CDS"); 3088 assert(UseCompressedClassPointers, "Only use with CompressedKlassPtrs"); 3089 address lower_base = MIN2((address)metaspace_base, cds_base); 3090 address higher_address = MAX2((address)(cds_base + FileMapInfo::shared_spaces_size()), 3091 (address)(metaspace_base + compressed_class_space_size())); 3092 return ((uint64_t)(higher_address - lower_base) <= UnscaledClassSpaceMax); 3093 } 3094 #endif 3095 3096 // Try to allocate the metaspace at the requested addr. 3097 void Metaspace::allocate_metaspace_compressed_klass_ptrs(char* requested_addr, address cds_base) { 3098 assert(using_class_space(), "called improperly"); 3099 assert(UseCompressedClassPointers, "Only use with CompressedKlassPtrs"); 3100 assert(compressed_class_space_size() < KlassEncodingMetaspaceMax, 3101 "Metaspace size is too big"); 3102 assert_is_ptr_aligned(requested_addr, _reserve_alignment); 3103 assert_is_ptr_aligned(cds_base, _reserve_alignment); 3104 assert_is_size_aligned(compressed_class_space_size(), _reserve_alignment); 3105 3106 // Don't use large pages for the class space. 3107 bool large_pages = false; 3108 3109 #if !(defined(AARCH64) || defined(AIX)) 3110 ReservedSpace metaspace_rs = ReservedSpace(compressed_class_space_size(), 3111 _reserve_alignment, 3112 large_pages, 3113 requested_addr); 3114 #else // AARCH64 3115 ReservedSpace metaspace_rs; 3116 3117 // Our compressed klass pointers may fit nicely into the lower 32 3118 // bits. 3119 if ((uint64_t)requested_addr + compressed_class_space_size() < 4*G) { 3120 metaspace_rs = ReservedSpace(compressed_class_space_size(), 3121 _reserve_alignment, 3122 large_pages, 3123 requested_addr); 3124 } 3125 3126 if (! metaspace_rs.is_reserved()) { 3127 // Aarch64: Try to align metaspace so that we can decode a compressed 3128 // klass with a single MOVK instruction. We can do this iff the 3129 // compressed class base is a multiple of 4G. 3130 // Aix: Search for a place where we can find memory. If we need to load 3131 // the base, 4G alignment is helpful, too. 3132 size_t increment = AARCH64_ONLY(4*)G; 3133 for (char *a = (char*)align_ptr_up(requested_addr, increment); 3134 a < (char*)(1024*G); 3135 a += increment) { 3136 if (a == (char *)(32*G)) { 3137 // Go faster from here on. Zero-based is no longer possible. 3138 increment = 4*G; 3139 } 3140 3141 #if INCLUDE_CDS 3142 if (UseSharedSpaces 3143 && ! can_use_cds_with_metaspace_addr(a, cds_base)) { 3144 // We failed to find an aligned base that will reach. Fall 3145 // back to using our requested addr. 3146 metaspace_rs = ReservedSpace(compressed_class_space_size(), 3147 _reserve_alignment, 3148 large_pages, 3149 requested_addr); 3150 break; 3151 } 3152 #endif 3153 3154 metaspace_rs = ReservedSpace(compressed_class_space_size(), 3155 _reserve_alignment, 3156 large_pages, 3157 a); 3158 if (metaspace_rs.is_reserved()) 3159 break; 3160 } 3161 } 3162 3163 #endif // AARCH64 3164 3165 if (!metaspace_rs.is_reserved()) { 3166 #if INCLUDE_CDS 3167 if (UseSharedSpaces) { 3168 size_t increment = align_size_up(1*G, _reserve_alignment); 3169 3170 // Keep trying to allocate the metaspace, increasing the requested_addr 3171 // by 1GB each time, until we reach an address that will no longer allow 3172 // use of CDS with compressed klass pointers. 3173 char *addr = requested_addr; 3174 while (!metaspace_rs.is_reserved() && (addr + increment > addr) && 3175 can_use_cds_with_metaspace_addr(addr + increment, cds_base)) { 3176 addr = addr + increment; 3177 metaspace_rs = ReservedSpace(compressed_class_space_size(), 3178 _reserve_alignment, large_pages, addr); 3179 } 3180 } 3181 #endif 3182 // If no successful allocation then try to allocate the space anywhere. If 3183 // that fails then OOM doom. At this point we cannot try allocating the 3184 // metaspace as if UseCompressedClassPointers is off because too much 3185 // initialization has happened that depends on UseCompressedClassPointers. 3186 // So, UseCompressedClassPointers cannot be turned off at this point. 3187 if (!metaspace_rs.is_reserved()) { 3188 metaspace_rs = ReservedSpace(compressed_class_space_size(), 3189 _reserve_alignment, large_pages); 3190 if (!metaspace_rs.is_reserved()) { 3191 vm_exit_during_initialization(err_msg("Could not allocate metaspace: " SIZE_FORMAT " bytes", 3192 compressed_class_space_size())); 3193 } 3194 } 3195 } 3196 3197 // If we got here then the metaspace got allocated. 3198 MemTracker::record_virtual_memory_type((address)metaspace_rs.base(), mtClass); 3199 3200 #if INCLUDE_CDS 3201 // Verify that we can use shared spaces. Otherwise, turn off CDS. 3202 if (UseSharedSpaces && !can_use_cds_with_metaspace_addr(metaspace_rs.base(), cds_base)) { 3203 FileMapInfo::stop_sharing_and_unmap( 3204 "Could not allocate metaspace at a compatible address"); 3205 } 3206 #endif 3207 set_narrow_klass_base_and_shift((address)metaspace_rs.base(), 3208 UseSharedSpaces ? (address)cds_base : 0); 3209 3210 initialize_class_space(metaspace_rs); 3211 3212 if (log_is_enabled(Trace, gc, metaspace)) { 3213 Log(gc, metaspace) log; 3214 ResourceMark rm; 3215 print_compressed_class_space(log.trace_stream(), requested_addr); 3216 } 3217 } 3218 3219 void Metaspace::print_compressed_class_space(outputStream* st, const char* requested_addr) { 3220 st->print_cr("Narrow klass base: " PTR_FORMAT ", Narrow klass shift: %d", 3221 p2i(Universe::narrow_klass_base()), Universe::narrow_klass_shift()); 3222 if (_class_space_list != NULL) { 3223 address base = (address)_class_space_list->current_virtual_space()->bottom(); 3224 st->print("Compressed class space size: " SIZE_FORMAT " Address: " PTR_FORMAT, 3225 compressed_class_space_size(), p2i(base)); 3226 if (requested_addr != 0) { 3227 st->print(" Req Addr: " PTR_FORMAT, p2i(requested_addr)); 3228 } 3229 st->cr(); 3230 } 3231 } 3232 3233 // For UseCompressedClassPointers the class space is reserved above the top of 3234 // the Java heap. The argument passed in is at the base of the compressed space. 3235 void Metaspace::initialize_class_space(ReservedSpace rs) { 3236 // The reserved space size may be bigger because of alignment, esp with UseLargePages 3237 assert(rs.size() >= CompressedClassSpaceSize, 3238 SIZE_FORMAT " != " SIZE_FORMAT, rs.size(), CompressedClassSpaceSize); 3239 assert(using_class_space(), "Must be using class space"); 3240 _class_space_list = new VirtualSpaceList(rs); 3241 _chunk_manager_class = new ChunkManager(ClassSpecializedChunk, ClassSmallChunk, ClassMediumChunk); 3242 3243 if (!_class_space_list->initialization_succeeded()) { 3244 vm_exit_during_initialization("Failed to setup compressed class space virtual space list."); 3245 } 3246 } 3247 3248 #endif 3249 3250 void Metaspace::ergo_initialize() { 3251 if (DumpSharedSpaces) { 3252 // Using large pages when dumping the shared archive is currently not implemented. 3253 FLAG_SET_ERGO(bool, UseLargePagesInMetaspace, false); 3254 } 3255 3256 size_t page_size = os::vm_page_size(); 3257 if (UseLargePages && UseLargePagesInMetaspace) { 3258 page_size = os::large_page_size(); 3259 } 3260 3261 _commit_alignment = page_size; 3262 _reserve_alignment = MAX2(page_size, (size_t)os::vm_allocation_granularity()); 3263 3264 // Do not use FLAG_SET_ERGO to update MaxMetaspaceSize, since this will 3265 // override if MaxMetaspaceSize was set on the command line or not. 3266 // This information is needed later to conform to the specification of the 3267 // java.lang.management.MemoryUsage API. 3268 // 3269 // Ideally, we would be able to set the default value of MaxMetaspaceSize in 3270 // globals.hpp to the aligned value, but this is not possible, since the 3271 // alignment depends on other flags being parsed. 3272 MaxMetaspaceSize = align_size_down_bounded(MaxMetaspaceSize, _reserve_alignment); 3273 3274 if (MetaspaceSize > MaxMetaspaceSize) { 3275 MetaspaceSize = MaxMetaspaceSize; 3276 } 3277 3278 MetaspaceSize = align_size_down_bounded(MetaspaceSize, _commit_alignment); 3279 3280 assert(MetaspaceSize <= MaxMetaspaceSize, "MetaspaceSize should be limited by MaxMetaspaceSize"); 3281 3282 MinMetaspaceExpansion = align_size_down_bounded(MinMetaspaceExpansion, _commit_alignment); 3283 MaxMetaspaceExpansion = align_size_down_bounded(MaxMetaspaceExpansion, _commit_alignment); 3284 3285 CompressedClassSpaceSize = align_size_down_bounded(CompressedClassSpaceSize, _reserve_alignment); 3286 set_compressed_class_space_size(CompressedClassSpaceSize); 3287 } 3288 3289 void Metaspace::global_initialize() { 3290 MetaspaceGC::initialize(); 3291 3292 // Initialize the alignment for shared spaces. 3293 int max_alignment = os::vm_allocation_granularity(); 3294 size_t cds_total = 0; 3295 3296 MetaspaceShared::set_max_alignment(max_alignment); 3297 3298 if (DumpSharedSpaces) { 3299 #if INCLUDE_CDS 3300 MetaspaceShared::estimate_regions_size(); 3301 3302 SharedReadOnlySize = align_size_up(SharedReadOnlySize, max_alignment); 3303 SharedReadWriteSize = align_size_up(SharedReadWriteSize, max_alignment); 3304 SharedMiscDataSize = align_size_up(SharedMiscDataSize, max_alignment); 3305 SharedMiscCodeSize = align_size_up(SharedMiscCodeSize, max_alignment); 3306 3307 // Initialize with the sum of the shared space sizes. The read-only 3308 // and read write metaspace chunks will be allocated out of this and the 3309 // remainder is the misc code and data chunks. 3310 cds_total = FileMapInfo::shared_spaces_size(); 3311 cds_total = align_size_up(cds_total, _reserve_alignment); 3312 _space_list = new VirtualSpaceList(cds_total/wordSize); 3313 _chunk_manager_metadata = new ChunkManager(SpecializedChunk, SmallChunk, MediumChunk); 3314 3315 if (!_space_list->initialization_succeeded()) { 3316 vm_exit_during_initialization("Unable to dump shared archive.", NULL); 3317 } 3318 3319 #ifdef _LP64 3320 if (cds_total + compressed_class_space_size() > UnscaledClassSpaceMax) { 3321 vm_exit_during_initialization("Unable to dump shared archive.", 3322 err_msg("Size of archive (" SIZE_FORMAT ") + compressed class space (" 3323 SIZE_FORMAT ") == total (" SIZE_FORMAT ") is larger than compressed " 3324 "klass limit: " UINT64_FORMAT, cds_total, compressed_class_space_size(), 3325 cds_total + compressed_class_space_size(), UnscaledClassSpaceMax)); 3326 } 3327 3328 // Set the compressed klass pointer base so that decoding of these pointers works 3329 // properly when creating the shared archive. 3330 assert(UseCompressedOops && UseCompressedClassPointers, 3331 "UseCompressedOops and UseCompressedClassPointers must be set"); 3332 Universe::set_narrow_klass_base((address)_space_list->current_virtual_space()->bottom()); 3333 log_develop_trace(gc, metaspace)("Setting_narrow_klass_base to Address: " PTR_FORMAT, 3334 p2i(_space_list->current_virtual_space()->bottom())); 3335 3336 Universe::set_narrow_klass_shift(0); 3337 #endif // _LP64 3338 #endif // INCLUDE_CDS 3339 } else { 3340 #if INCLUDE_CDS 3341 if (UseSharedSpaces) { 3342 // If using shared space, open the file that contains the shared space 3343 // and map in the memory before initializing the rest of metaspace (so 3344 // the addresses don't conflict) 3345 address cds_address = NULL; 3346 FileMapInfo* mapinfo = new FileMapInfo(); 3347 3348 // Open the shared archive file, read and validate the header. If 3349 // initialization fails, shared spaces [UseSharedSpaces] are 3350 // disabled and the file is closed. 3351 // Map in spaces now also 3352 if (mapinfo->initialize() && MetaspaceShared::map_shared_spaces(mapinfo)) { 3353 cds_total = FileMapInfo::shared_spaces_size(); 3354 cds_address = (address)mapinfo->header()->region_addr(0); 3355 #ifdef _LP64 3356 if (using_class_space()) { 3357 char* cds_end = (char*)(cds_address + cds_total); 3358 cds_end = (char *)align_ptr_up(cds_end, _reserve_alignment); 3359 // If UseCompressedClassPointers is set then allocate the metaspace area 3360 // above the heap and above the CDS area (if it exists). 3361 allocate_metaspace_compressed_klass_ptrs(cds_end, cds_address); 3362 // Map the shared string space after compressed pointers 3363 // because it relies on compressed class pointers setting to work 3364 mapinfo->map_string_regions(); 3365 } 3366 #endif // _LP64 3367 } else { 3368 assert(!mapinfo->is_open() && !UseSharedSpaces, 3369 "archive file not closed or shared spaces not disabled."); 3370 } 3371 } 3372 #endif // INCLUDE_CDS 3373 3374 #ifdef _LP64 3375 if (!UseSharedSpaces && using_class_space()) { 3376 char* base = (char*)align_ptr_up(Universe::heap()->reserved_region().end(), _reserve_alignment); 3377 allocate_metaspace_compressed_klass_ptrs(base, 0); 3378 } 3379 #endif // _LP64 3380 3381 // Initialize these before initializing the VirtualSpaceList 3382 _first_chunk_word_size = InitialBootClassLoaderMetaspaceSize / BytesPerWord; 3383 _first_chunk_word_size = align_word_size_up(_first_chunk_word_size); 3384 // Make the first class chunk bigger than a medium chunk so it's not put 3385 // on the medium chunk list. The next chunk will be small and progress 3386 // from there. This size calculated by -version. 3387 _first_class_chunk_word_size = MIN2((size_t)MediumChunk*6, 3388 (CompressedClassSpaceSize/BytesPerWord)*2); 3389 _first_class_chunk_word_size = align_word_size_up(_first_class_chunk_word_size); 3390 // Arbitrarily set the initial virtual space to a multiple 3391 // of the boot class loader size. 3392 size_t word_size = VIRTUALSPACEMULTIPLIER * _first_chunk_word_size; 3393 word_size = align_size_up(word_size, Metaspace::reserve_alignment_words()); 3394 3395 // Initialize the list of virtual spaces. 3396 _space_list = new VirtualSpaceList(word_size); 3397 _chunk_manager_metadata = new ChunkManager(SpecializedChunk, SmallChunk, MediumChunk); 3398 3399 if (!_space_list->initialization_succeeded()) { 3400 vm_exit_during_initialization("Unable to setup metadata virtual space list.", NULL); 3401 } 3402 } 3403 3404 _tracer = new MetaspaceTracer(); 3405 } 3406 3407 void Metaspace::post_initialize() { 3408 MetaspaceGC::post_initialize(); 3409 } 3410 3411 void Metaspace::initialize_first_chunk(MetaspaceType type, MetadataType mdtype) { 3412 Metachunk* chunk = get_initialization_chunk(type, mdtype); 3413 if (chunk != NULL) { 3414 // Add to this manager's list of chunks in use and current_chunk(). 3415 get_space_manager(mdtype)->add_chunk(chunk, true); 3416 } 3417 } 3418 3419 Metachunk* Metaspace::get_initialization_chunk(MetaspaceType type, MetadataType mdtype) { 3420 size_t chunk_word_size = get_space_manager(mdtype)->get_initial_chunk_size(type); 3421 3422 // Get a chunk from the chunk freelist 3423 Metachunk* chunk = get_chunk_manager(mdtype)->chunk_freelist_allocate(chunk_word_size); 3424 3425 if (chunk == NULL) { 3426 chunk = get_space_list(mdtype)->get_new_chunk(chunk_word_size, 3427 get_space_manager(mdtype)->medium_chunk_bunch()); 3428 } 3429 3430 // For dumping shared archive, report error if allocation has failed. 3431 if (DumpSharedSpaces && chunk == NULL) { 3432 report_insufficient_metaspace(MetaspaceAux::committed_bytes() + chunk_word_size * BytesPerWord); 3433 } 3434 3435 return chunk; 3436 } 3437 3438 void Metaspace::verify_global_initialization() { 3439 assert(space_list() != NULL, "Metadata VirtualSpaceList has not been initialized"); 3440 assert(chunk_manager_metadata() != NULL, "Metadata ChunkManager has not been initialized"); 3441 3442 if (using_class_space()) { 3443 assert(class_space_list() != NULL, "Class VirtualSpaceList has not been initialized"); 3444 assert(chunk_manager_class() != NULL, "Class ChunkManager has not been initialized"); 3445 } 3446 } 3447 3448 void Metaspace::initialize(Mutex* lock, MetaspaceType type) { 3449 verify_global_initialization(); 3450 3451 // Allocate SpaceManager for metadata objects. 3452 _vsm = new SpaceManager(NonClassType, lock); 3453 3454 if (using_class_space()) { 3455 // Allocate SpaceManager for classes. 3456 _class_vsm = new SpaceManager(ClassType, lock); 3457 } 3458 3459 MutexLockerEx cl(SpaceManager::expand_lock(), Mutex::_no_safepoint_check_flag); 3460 3461 // Allocate chunk for metadata objects 3462 initialize_first_chunk(type, NonClassType); 3463 3464 // Allocate chunk for class metadata objects 3465 if (using_class_space()) { 3466 initialize_first_chunk(type, ClassType); 3467 } 3468 3469 _alloc_record_head = NULL; 3470 _alloc_record_tail = NULL; 3471 } 3472 3473 size_t Metaspace::align_word_size_up(size_t word_size) { 3474 size_t byte_size = word_size * wordSize; 3475 return ReservedSpace::allocation_align_size_up(byte_size) / wordSize; 3476 } 3477 3478 MetaWord* Metaspace::allocate(size_t word_size, MetadataType mdtype) { 3479 // DumpSharedSpaces doesn't use class metadata area (yet) 3480 // Also, don't use class_vsm() unless UseCompressedClassPointers is true. 3481 if (is_class_space_allocation(mdtype)) { 3482 return class_vsm()->allocate(word_size); 3483 } else { 3484 return vsm()->allocate(word_size); 3485 } 3486 } 3487 3488 MetaWord* Metaspace::expand_and_allocate(size_t word_size, MetadataType mdtype) { 3489 size_t delta_bytes = MetaspaceGC::delta_capacity_until_GC(word_size * BytesPerWord); 3490 assert(delta_bytes > 0, "Must be"); 3491 3492 size_t before = 0; 3493 size_t after = 0; 3494 MetaWord* res; 3495 bool incremented; 3496 3497 // Each thread increments the HWM at most once. Even if the thread fails to increment 3498 // the HWM, an allocation is still attempted. This is because another thread must then 3499 // have incremented the HWM and therefore the allocation might still succeed. 3500 do { 3501 incremented = MetaspaceGC::inc_capacity_until_GC(delta_bytes, &after, &before); 3502 res = allocate(word_size, mdtype); 3503 } while (!incremented && res == NULL); 3504 3505 if (incremented) { 3506 tracer()->report_gc_threshold(before, after, 3507 MetaspaceGCThresholdUpdater::ExpandAndAllocate); 3508 log_trace(gc, metaspace)("Increase capacity to GC from " SIZE_FORMAT " to " SIZE_FORMAT, before, after); 3509 } 3510 3511 return res; 3512 } 3513 3514 // Space allocated in the Metaspace. This may 3515 // be across several metadata virtual spaces. 3516 char* Metaspace::bottom() const { 3517 assert(DumpSharedSpaces, "only useful and valid for dumping shared spaces"); 3518 return (char*)vsm()->current_chunk()->bottom(); 3519 } 3520 3521 size_t Metaspace::used_words_slow(MetadataType mdtype) const { 3522 if (mdtype == ClassType) { 3523 return using_class_space() ? class_vsm()->sum_used_in_chunks_in_use() : 0; 3524 } else { 3525 return vsm()->sum_used_in_chunks_in_use(); // includes overhead! 3526 } 3527 } 3528 3529 size_t Metaspace::free_words_slow(MetadataType mdtype) const { 3530 if (mdtype == ClassType) { 3531 return using_class_space() ? class_vsm()->sum_free_in_chunks_in_use() : 0; 3532 } else { 3533 return vsm()->sum_free_in_chunks_in_use(); 3534 } 3535 } 3536 3537 // Space capacity in the Metaspace. It includes 3538 // space in the list of chunks from which allocations 3539 // have been made. Don't include space in the global freelist and 3540 // in the space available in the dictionary which 3541 // is already counted in some chunk. 3542 size_t Metaspace::capacity_words_slow(MetadataType mdtype) const { 3543 if (mdtype == ClassType) { 3544 return using_class_space() ? class_vsm()->sum_capacity_in_chunks_in_use() : 0; 3545 } else { 3546 return vsm()->sum_capacity_in_chunks_in_use(); 3547 } 3548 } 3549 3550 size_t Metaspace::used_bytes_slow(MetadataType mdtype) const { 3551 return used_words_slow(mdtype) * BytesPerWord; 3552 } 3553 3554 size_t Metaspace::capacity_bytes_slow(MetadataType mdtype) const { 3555 return capacity_words_slow(mdtype) * BytesPerWord; 3556 } 3557 3558 size_t Metaspace::allocated_blocks_bytes() const { 3559 return vsm()->allocated_blocks_bytes() + 3560 (using_class_space() ? class_vsm()->allocated_blocks_bytes() : 0); 3561 } 3562 3563 size_t Metaspace::allocated_chunks_bytes() const { 3564 return vsm()->allocated_chunks_bytes() + 3565 (using_class_space() ? class_vsm()->allocated_chunks_bytes() : 0); 3566 } 3567 3568 void Metaspace::deallocate(MetaWord* ptr, size_t word_size, bool is_class) { 3569 assert(!SafepointSynchronize::is_at_safepoint() 3570 || Thread::current()->is_VM_thread(), "should be the VM thread"); 3571 3572 if (DumpSharedSpaces && log_is_enabled(Info, cds)) { 3573 record_deallocation(ptr, vsm()->get_allocation_word_size(word_size)); 3574 } 3575 3576 MutexLockerEx ml(vsm()->lock(), Mutex::_no_safepoint_check_flag); 3577 3578 if (is_class && using_class_space()) { 3579 class_vsm()->deallocate(ptr, word_size); 3580 } else { 3581 vsm()->deallocate(ptr, word_size); 3582 } 3583 } 3584 3585 3586 MetaWord* Metaspace::allocate(ClassLoaderData* loader_data, size_t word_size, 3587 bool read_only, MetaspaceObj::Type type, TRAPS) { 3588 if (HAS_PENDING_EXCEPTION) { 3589 assert(false, "Should not allocate with exception pending"); 3590 return NULL; // caller does a CHECK_NULL too 3591 } 3592 3593 assert(loader_data != NULL, "Should never pass around a NULL loader_data. " 3594 "ClassLoaderData::the_null_class_loader_data() should have been used."); 3595 3596 // Allocate in metaspaces without taking out a lock, because it deadlocks 3597 // with the SymbolTable_lock. Dumping is single threaded for now. We'll have 3598 // to revisit this for application class data sharing. 3599 if (DumpSharedSpaces) { 3600 assert(type > MetaspaceObj::UnknownType && type < MetaspaceObj::_number_of_types, "sanity"); 3601 Metaspace* space = read_only ? loader_data->ro_metaspace() : loader_data->rw_metaspace(); 3602 MetaWord* result = space->allocate(word_size, NonClassType); 3603 if (result == NULL) { 3604 report_out_of_shared_space(read_only ? SharedReadOnly : SharedReadWrite); 3605 } 3606 if (log_is_enabled(Info, cds)) { 3607 space->record_allocation(result, type, space->vsm()->get_allocation_word_size(word_size)); 3608 } 3609 3610 // Zero initialize. 3611 Copy::fill_to_words((HeapWord*)result, word_size, 0); 3612 3613 return result; 3614 } 3615 3616 MetadataType mdtype = (type == MetaspaceObj::ClassType) ? ClassType : NonClassType; 3617 3618 // Try to allocate metadata. 3619 MetaWord* result = loader_data->metaspace_non_null()->allocate(word_size, mdtype); 3620 3621 if (result == NULL) { 3622 tracer()->report_metaspace_allocation_failure(loader_data, word_size, type, mdtype); 3623 3624 // Allocation failed. 3625 if (is_init_completed()) { 3626 // Only start a GC if the bootstrapping has completed. 3627 3628 // Try to clean out some memory and retry. 3629 result = Universe::heap()->collector_policy()->satisfy_failed_metadata_allocation( 3630 loader_data, word_size, mdtype); 3631 } 3632 } 3633 3634 if (result == NULL) { 3635 SpaceManager* sm; 3636 if (is_class_space_allocation(mdtype)) { 3637 sm = loader_data->metaspace_non_null()->class_vsm(); 3638 } else { 3639 sm = loader_data->metaspace_non_null()->vsm(); 3640 } 3641 3642 result = sm->get_small_chunk_and_allocate(word_size); 3643 3644 if (result == NULL) { 3645 report_metadata_oome(loader_data, word_size, type, mdtype, CHECK_NULL); 3646 } 3647 } 3648 3649 // Zero initialize. 3650 Copy::fill_to_words((HeapWord*)result, word_size, 0); 3651 3652 return result; 3653 } 3654 3655 size_t Metaspace::class_chunk_size(size_t word_size) { 3656 assert(using_class_space(), "Has to use class space"); 3657 return class_vsm()->calc_chunk_size(word_size); 3658 } 3659 3660 void Metaspace::report_metadata_oome(ClassLoaderData* loader_data, size_t word_size, MetaspaceObj::Type type, MetadataType mdtype, TRAPS) { 3661 tracer()->report_metadata_oom(loader_data, word_size, type, mdtype); 3662 3663 // If result is still null, we are out of memory. 3664 Log(gc, metaspace, freelist) log; 3665 if (log.is_info()) { 3666 log.info("Metaspace (%s) allocation failed for size " SIZE_FORMAT, 3667 is_class_space_allocation(mdtype) ? "class" : "data", word_size); 3668 ResourceMark rm; 3669 outputStream* out = log.info_stream(); 3670 if (loader_data->metaspace_or_null() != NULL) { 3671 loader_data->dump(out); 3672 } 3673 MetaspaceAux::dump(out); 3674 } 3675 3676 bool out_of_compressed_class_space = false; 3677 if (is_class_space_allocation(mdtype)) { 3678 Metaspace* metaspace = loader_data->metaspace_non_null(); 3679 out_of_compressed_class_space = 3680 MetaspaceAux::committed_bytes(Metaspace::ClassType) + 3681 (metaspace->class_chunk_size(word_size) * BytesPerWord) > 3682 CompressedClassSpaceSize; 3683 } 3684 3685 // -XX:+HeapDumpOnOutOfMemoryError and -XX:OnOutOfMemoryError support 3686 const char* space_string = out_of_compressed_class_space ? 3687 "Compressed class space" : "Metaspace"; 3688 3689 report_java_out_of_memory(space_string); 3690 3691 if (JvmtiExport::should_post_resource_exhausted()) { 3692 JvmtiExport::post_resource_exhausted( 3693 JVMTI_RESOURCE_EXHAUSTED_OOM_ERROR, 3694 space_string); 3695 } 3696 3697 if (!is_init_completed()) { 3698 vm_exit_during_initialization("OutOfMemoryError", space_string); 3699 } 3700 3701 if (out_of_compressed_class_space) { 3702 THROW_OOP(Universe::out_of_memory_error_class_metaspace()); 3703 } else { 3704 THROW_OOP(Universe::out_of_memory_error_metaspace()); 3705 } 3706 } 3707 3708 const char* Metaspace::metadata_type_name(Metaspace::MetadataType mdtype) { 3709 switch (mdtype) { 3710 case Metaspace::ClassType: return "Class"; 3711 case Metaspace::NonClassType: return "Metadata"; 3712 default: 3713 assert(false, "Got bad mdtype: %d", (int) mdtype); 3714 return NULL; 3715 } 3716 } 3717 3718 void Metaspace::record_allocation(void* ptr, MetaspaceObj::Type type, size_t word_size) { 3719 assert(DumpSharedSpaces, "sanity"); 3720 3721 int byte_size = (int)word_size * wordSize; 3722 AllocRecord *rec = new AllocRecord((address)ptr, type, byte_size); 3723 3724 if (_alloc_record_head == NULL) { 3725 _alloc_record_head = _alloc_record_tail = rec; 3726 } else if (_alloc_record_tail->_ptr + _alloc_record_tail->_byte_size == (address)ptr) { 3727 _alloc_record_tail->_next = rec; 3728 _alloc_record_tail = rec; 3729 } else { 3730 // slow linear search, but this doesn't happen that often, and only when dumping 3731 for (AllocRecord *old = _alloc_record_head; old; old = old->_next) { 3732 if (old->_ptr == ptr) { 3733 assert(old->_type == MetaspaceObj::DeallocatedType, "sanity"); 3734 int remain_bytes = old->_byte_size - byte_size; 3735 assert(remain_bytes >= 0, "sanity"); 3736 old->_type = type; 3737 3738 if (remain_bytes == 0) { 3739 delete(rec); 3740 } else { 3741 address remain_ptr = address(ptr) + byte_size; 3742 rec->_ptr = remain_ptr; 3743 rec->_byte_size = remain_bytes; 3744 rec->_type = MetaspaceObj::DeallocatedType; 3745 rec->_next = old->_next; 3746 old->_byte_size = byte_size; 3747 old->_next = rec; 3748 } 3749 return; 3750 } 3751 } 3752 assert(0, "reallocating a freed pointer that was not recorded"); 3753 } 3754 } 3755 3756 void Metaspace::record_deallocation(void* ptr, size_t word_size) { 3757 assert(DumpSharedSpaces, "sanity"); 3758 3759 for (AllocRecord *rec = _alloc_record_head; rec; rec = rec->_next) { 3760 if (rec->_ptr == ptr) { 3761 assert(rec->_byte_size == (int)word_size * wordSize, "sanity"); 3762 rec->_type = MetaspaceObj::DeallocatedType; 3763 return; 3764 } 3765 } 3766 3767 assert(0, "deallocating a pointer that was not recorded"); 3768 } 3769 3770 void Metaspace::iterate(Metaspace::AllocRecordClosure *closure) { 3771 assert(DumpSharedSpaces, "unimplemented for !DumpSharedSpaces"); 3772 3773 address last_addr = (address)bottom(); 3774 3775 for (AllocRecord *rec = _alloc_record_head; rec; rec = rec->_next) { 3776 address ptr = rec->_ptr; 3777 if (last_addr < ptr) { 3778 closure->doit(last_addr, MetaspaceObj::UnknownType, ptr - last_addr); 3779 } 3780 closure->doit(ptr, rec->_type, rec->_byte_size); 3781 last_addr = ptr + rec->_byte_size; 3782 } 3783 3784 address top = ((address)bottom()) + used_bytes_slow(Metaspace::NonClassType); 3785 if (last_addr < top) { 3786 closure->doit(last_addr, MetaspaceObj::UnknownType, top - last_addr); 3787 } 3788 } 3789 3790 void Metaspace::purge(MetadataType mdtype) { 3791 get_space_list(mdtype)->purge(get_chunk_manager(mdtype)); 3792 } 3793 3794 void Metaspace::purge() { 3795 MutexLockerEx cl(SpaceManager::expand_lock(), 3796 Mutex::_no_safepoint_check_flag); 3797 purge(NonClassType); 3798 if (using_class_space()) { 3799 purge(ClassType); 3800 } 3801 } 3802 3803 void Metaspace::print_on(outputStream* out) const { 3804 // Print both class virtual space counts and metaspace. 3805 if (Verbose) { 3806 vsm()->print_on(out); 3807 if (using_class_space()) { 3808 class_vsm()->print_on(out); 3809 } 3810 } 3811 } 3812 3813 bool Metaspace::contains(const void* ptr) { 3814 if (UseSharedSpaces && MetaspaceShared::is_in_shared_space(ptr)) { 3815 return true; 3816 } 3817 return contains_non_shared(ptr); 3818 } 3819 3820 bool Metaspace::contains_non_shared(const void* ptr) { 3821 if (using_class_space() && get_space_list(ClassType)->contains(ptr)) { 3822 return true; 3823 } 3824 3825 return get_space_list(NonClassType)->contains(ptr); 3826 } 3827 3828 void Metaspace::verify() { 3829 vsm()->verify(); 3830 if (using_class_space()) { 3831 class_vsm()->verify(); 3832 } 3833 } 3834 3835 void Metaspace::dump(outputStream* const out) const { 3836 out->print_cr("\nVirtual space manager: " INTPTR_FORMAT, p2i(vsm())); 3837 vsm()->dump(out); 3838 if (using_class_space()) { 3839 out->print_cr("\nClass space manager: " INTPTR_FORMAT, p2i(class_vsm())); 3840 class_vsm()->dump(out); 3841 } 3842 } 3843 3844 /////////////// Unit tests /////////////// 3845 3846 #ifndef PRODUCT 3847 3848 class TestMetaspaceAuxTest : AllStatic { 3849 public: 3850 static void test_reserved() { 3851 size_t reserved = MetaspaceAux::reserved_bytes(); 3852 3853 assert(reserved > 0, "assert"); 3854 3855 size_t committed = MetaspaceAux::committed_bytes(); 3856 assert(committed <= reserved, "assert"); 3857 3858 size_t reserved_metadata = MetaspaceAux::reserved_bytes(Metaspace::NonClassType); 3859 assert(reserved_metadata > 0, "assert"); 3860 assert(reserved_metadata <= reserved, "assert"); 3861 3862 if (UseCompressedClassPointers) { 3863 size_t reserved_class = MetaspaceAux::reserved_bytes(Metaspace::ClassType); 3864 assert(reserved_class > 0, "assert"); 3865 assert(reserved_class < reserved, "assert"); 3866 } 3867 } 3868 3869 static void test_committed() { 3870 size_t committed = MetaspaceAux::committed_bytes(); 3871 3872 assert(committed > 0, "assert"); 3873 3874 size_t reserved = MetaspaceAux::reserved_bytes(); 3875 assert(committed <= reserved, "assert"); 3876 3877 size_t committed_metadata = MetaspaceAux::committed_bytes(Metaspace::NonClassType); 3878 assert(committed_metadata > 0, "assert"); 3879 assert(committed_metadata <= committed, "assert"); 3880 3881 if (UseCompressedClassPointers) { 3882 size_t committed_class = MetaspaceAux::committed_bytes(Metaspace::ClassType); 3883 assert(committed_class > 0, "assert"); 3884 assert(committed_class < committed, "assert"); 3885 } 3886 } 3887 3888 static void test_virtual_space_list_large_chunk() { 3889 VirtualSpaceList* vs_list = new VirtualSpaceList(os::vm_allocation_granularity()); 3890 MutexLockerEx cl(SpaceManager::expand_lock(), Mutex::_no_safepoint_check_flag); 3891 // A size larger than VirtualSpaceSize (256k) and add one page to make it _not_ be 3892 // vm_allocation_granularity aligned on Windows. 3893 size_t large_size = (size_t)(2*256*K + (os::vm_page_size()/BytesPerWord)); 3894 large_size += (os::vm_page_size()/BytesPerWord); 3895 vs_list->get_new_chunk(large_size, 0); 3896 } 3897 3898 static void test() { 3899 test_reserved(); 3900 test_committed(); 3901 test_virtual_space_list_large_chunk(); 3902 } 3903 }; 3904 3905 void TestMetaspaceAux_test() { 3906 TestMetaspaceAuxTest::test(); 3907 } 3908 3909 class TestVirtualSpaceNodeTest { 3910 static void chunk_up(size_t words_left, size_t& num_medium_chunks, 3911 size_t& num_small_chunks, 3912 size_t& num_specialized_chunks) { 3913 num_medium_chunks = words_left / MediumChunk; 3914 words_left = words_left % MediumChunk; 3915 3916 num_small_chunks = words_left / SmallChunk; 3917 words_left = words_left % SmallChunk; 3918 // how many specialized chunks can we get? 3919 num_specialized_chunks = words_left / SpecializedChunk; 3920 assert(words_left % SpecializedChunk == 0, "should be nothing left"); 3921 } 3922 3923 public: 3924 static void test() { 3925 MutexLockerEx ml(SpaceManager::expand_lock(), Mutex::_no_safepoint_check_flag); 3926 const size_t vsn_test_size_words = MediumChunk * 4; 3927 const size_t vsn_test_size_bytes = vsn_test_size_words * BytesPerWord; 3928 3929 // The chunk sizes must be multiples of eachother, or this will fail 3930 STATIC_ASSERT(MediumChunk % SmallChunk == 0); 3931 STATIC_ASSERT(SmallChunk % SpecializedChunk == 0); 3932 3933 { // No committed memory in VSN 3934 ChunkManager cm(SpecializedChunk, SmallChunk, MediumChunk); 3935 VirtualSpaceNode vsn(vsn_test_size_bytes); 3936 vsn.initialize(); 3937 vsn.retire(&cm); 3938 assert(cm.sum_free_chunks_count() == 0, "did not commit any memory in the VSN"); 3939 } 3940 3941 { // All of VSN is committed, half is used by chunks 3942 ChunkManager cm(SpecializedChunk, SmallChunk, MediumChunk); 3943 VirtualSpaceNode vsn(vsn_test_size_bytes); 3944 vsn.initialize(); 3945 vsn.expand_by(vsn_test_size_words, vsn_test_size_words); 3946 vsn.get_chunk_vs(MediumChunk); 3947 vsn.get_chunk_vs(MediumChunk); 3948 vsn.retire(&cm); 3949 assert(cm.sum_free_chunks_count() == 2, "should have been memory left for 2 medium chunks"); 3950 assert(cm.sum_free_chunks() == 2*MediumChunk, "sizes should add up"); 3951 } 3952 3953 const size_t page_chunks = 4 * (size_t)os::vm_page_size() / BytesPerWord; 3954 // This doesn't work for systems with vm_page_size >= 16K. 3955 if (page_chunks < MediumChunk) { 3956 // 4 pages of VSN is committed, some is used by chunks 3957 ChunkManager cm(SpecializedChunk, SmallChunk, MediumChunk); 3958 VirtualSpaceNode vsn(vsn_test_size_bytes); 3959 3960 vsn.initialize(); 3961 vsn.expand_by(page_chunks, page_chunks); 3962 vsn.get_chunk_vs(SmallChunk); 3963 vsn.get_chunk_vs(SpecializedChunk); 3964 vsn.retire(&cm); 3965 3966 // committed - used = words left to retire 3967 const size_t words_left = page_chunks - SmallChunk - SpecializedChunk; 3968 3969 size_t num_medium_chunks, num_small_chunks, num_spec_chunks; 3970 chunk_up(words_left, num_medium_chunks, num_small_chunks, num_spec_chunks); 3971 3972 assert(num_medium_chunks == 0, "should not get any medium chunks"); 3973 assert(cm.sum_free_chunks_count() == (num_small_chunks + num_spec_chunks), "should be space for 3 chunks"); 3974 assert(cm.sum_free_chunks() == words_left, "sizes should add up"); 3975 } 3976 3977 { // Half of VSN is committed, a humongous chunk is used 3978 ChunkManager cm(SpecializedChunk, SmallChunk, MediumChunk); 3979 VirtualSpaceNode vsn(vsn_test_size_bytes); 3980 vsn.initialize(); 3981 vsn.expand_by(MediumChunk * 2, MediumChunk * 2); 3982 vsn.get_chunk_vs(MediumChunk + SpecializedChunk); // Humongous chunks will be aligned up to MediumChunk + SpecializedChunk 3983 vsn.retire(&cm); 3984 3985 const size_t words_left = MediumChunk * 2 - (MediumChunk + SpecializedChunk); 3986 size_t num_medium_chunks, num_small_chunks, num_spec_chunks; 3987 chunk_up(words_left, num_medium_chunks, num_small_chunks, num_spec_chunks); 3988 3989 assert(num_medium_chunks == 0, "should not get any medium chunks"); 3990 assert(cm.sum_free_chunks_count() == (num_small_chunks + num_spec_chunks), "should be space for 3 chunks"); 3991 assert(cm.sum_free_chunks() == words_left, "sizes should add up"); 3992 } 3993 3994 } 3995 3996 #define assert_is_available_positive(word_size) \ 3997 assert(vsn.is_available(word_size), \ 3998 #word_size ": " PTR_FORMAT " bytes were not available in " \ 3999 "VirtualSpaceNode [" PTR_FORMAT ", " PTR_FORMAT ")", \ 4000 (uintptr_t)(word_size * BytesPerWord), p2i(vsn.bottom()), p2i(vsn.end())); 4001 4002 #define assert_is_available_negative(word_size) \ 4003 assert(!vsn.is_available(word_size), \ 4004 #word_size ": " PTR_FORMAT " bytes should not be available in " \ 4005 "VirtualSpaceNode [" PTR_FORMAT ", " PTR_FORMAT ")", \ 4006 (uintptr_t)(word_size * BytesPerWord), p2i(vsn.bottom()), p2i(vsn.end())); 4007 4008 static void test_is_available_positive() { 4009 // Reserve some memory. 4010 VirtualSpaceNode vsn(os::vm_allocation_granularity()); 4011 assert(vsn.initialize(), "Failed to setup VirtualSpaceNode"); 4012 4013 // Commit some memory. 4014 size_t commit_word_size = os::vm_allocation_granularity() / BytesPerWord; 4015 bool expanded = vsn.expand_by(commit_word_size, commit_word_size); 4016 assert(expanded, "Failed to commit"); 4017 4018 // Check that is_available accepts the committed size. 4019 assert_is_available_positive(commit_word_size); 4020 4021 // Check that is_available accepts half the committed size. 4022 size_t expand_word_size = commit_word_size / 2; 4023 assert_is_available_positive(expand_word_size); 4024 } 4025 4026 static void test_is_available_negative() { 4027 // Reserve some memory. 4028 VirtualSpaceNode vsn(os::vm_allocation_granularity()); 4029 assert(vsn.initialize(), "Failed to setup VirtualSpaceNode"); 4030 4031 // Commit some memory. 4032 size_t commit_word_size = os::vm_allocation_granularity() / BytesPerWord; 4033 bool expanded = vsn.expand_by(commit_word_size, commit_word_size); 4034 assert(expanded, "Failed to commit"); 4035 4036 // Check that is_available doesn't accept a too large size. 4037 size_t two_times_commit_word_size = commit_word_size * 2; 4038 assert_is_available_negative(two_times_commit_word_size); 4039 } 4040 4041 static void test_is_available_overflow() { 4042 // Reserve some memory. 4043 VirtualSpaceNode vsn(os::vm_allocation_granularity()); 4044 assert(vsn.initialize(), "Failed to setup VirtualSpaceNode"); 4045 4046 // Commit some memory. 4047 size_t commit_word_size = os::vm_allocation_granularity() / BytesPerWord; 4048 bool expanded = vsn.expand_by(commit_word_size, commit_word_size); 4049 assert(expanded, "Failed to commit"); 4050 4051 // Calculate a size that will overflow the virtual space size. 4052 void* virtual_space_max = (void*)(uintptr_t)-1; 4053 size_t bottom_to_max = pointer_delta(virtual_space_max, vsn.bottom(), 1); 4054 size_t overflow_size = bottom_to_max + BytesPerWord; 4055 size_t overflow_word_size = overflow_size / BytesPerWord; 4056 4057 // Check that is_available can handle the overflow. 4058 assert_is_available_negative(overflow_word_size); 4059 } 4060 4061 static void test_is_available() { 4062 TestVirtualSpaceNodeTest::test_is_available_positive(); 4063 TestVirtualSpaceNodeTest::test_is_available_negative(); 4064 TestVirtualSpaceNodeTest::test_is_available_overflow(); 4065 } 4066 }; 4067 4068 void TestVirtualSpaceNode_test() { 4069 TestVirtualSpaceNodeTest::test(); 4070 TestVirtualSpaceNodeTest::test_is_available(); 4071 } 4072 4073 // The following test is placed here instead of a gtest / unittest file 4074 // because the ChunkManager class is only available in this file. 4075 void ChunkManager_test_list_index() { 4076 ChunkManager manager(ClassSpecializedChunk, ClassSmallChunk, ClassMediumChunk); 4077 4078 // Test previous bug where a query for a humongous class metachunk, 4079 // incorrectly matched the non-class medium metachunk size. 4080 { 4081 assert(MediumChunk > ClassMediumChunk, "Precondition for test"); 4082 4083 ChunkIndex index = manager.list_index(MediumChunk); 4084 4085 assert(index == HumongousIndex, 4086 "Requested size is larger than ClassMediumChunk," 4087 " so should return HumongousIndex. Got index: %d", (int)index); 4088 } 4089 4090 // Check the specified sizes as well. 4091 { 4092 ChunkIndex index = manager.list_index(ClassSpecializedChunk); 4093 assert(index == SpecializedIndex, "Wrong index returned. Got index: %d", (int)index); 4094 } 4095 { 4096 ChunkIndex index = manager.list_index(ClassSmallChunk); 4097 assert(index == SmallIndex, "Wrong index returned. Got index: %d", (int)index); 4098 } 4099 { 4100 ChunkIndex index = manager.list_index(ClassMediumChunk); 4101 assert(index == MediumIndex, "Wrong index returned. Got index: %d", (int)index); 4102 } 4103 { 4104 ChunkIndex index = manager.list_index(ClassMediumChunk + 1); 4105 assert(index == HumongousIndex, "Wrong index returned. Got index: %d", (int)index); 4106 } 4107 } 4108 4109 #endif // !PRODUCT 4110 4111 #ifdef ASSERT 4112 4113 // ChunkManagerReturnTest stresses taking/returning chunks from the ChunkManager. It takes and 4114 // returns chunks from/to the ChunkManager while keeping track of the expected ChunkManager 4115 // content. 4116 class ChunkManagerReturnTestImpl { 4117 4118 VirtualSpaceNode _vsn; 4119 ChunkManager _cm; 4120 4121 // The expected content of the chunk manager. 4122 unsigned _chunks_in_chunkmanager; 4123 size_t _words_in_chunkmanager; 4124 4125 // A fixed size pool of chunks. Chunks may be in the chunk manager (free) or not (in use). 4126 static const int num_chunks = 256; 4127 Metachunk* _pool[num_chunks]; 4128 4129 // Helper, return a random position into the chunk pool. 4130 static int get_random_position() { 4131 return os::random() % num_chunks; 4132 } 4133 4134 // Asserts that ChunkManager counters match expectations. 4135 void assert_counters() { 4136 assert(_vsn.container_count() == num_chunks - _chunks_in_chunkmanager, "vsn counter mismatch."); 4137 assert(_cm.free_chunks_count() == _chunks_in_chunkmanager, "cm counter mismatch."); 4138 assert(_cm.free_chunks_total_words() == _words_in_chunkmanager, "cm counter mismatch."); 4139 } 4140 4141 // Get a random chunk size. Equal chance to get spec/med/small chunk size or 4142 // a humongous chunk size. The latter itself is random in the range of [med+spec..4*med). 4143 size_t get_random_chunk_size() { 4144 const size_t sizes [] = { SpecializedChunk, SmallChunk, MediumChunk }; 4145 const int rand = os::random() % 4; 4146 if (rand < 3) { 4147 return sizes[rand]; 4148 } else { 4149 // Note: this affects the max. size of space (see _vsn initialization in ctor). 4150 return align_size_up(MediumChunk + 1 + (os::random() % (MediumChunk * 4)), SpecializedChunk); 4151 } 4152 } 4153 4154 // Starting at pool index <start>+1, find the next chunk tagged as either free or in use, depending 4155 // on <is_free>. Search wraps. Returns its position, or -1 if no matching chunk was found. 4156 int next_matching_chunk(int start, bool is_free) const { 4157 assert(start >= 0 && start < num_chunks, "invalid parameter"); 4158 int pos = start; 4159 do { 4160 if (++pos == num_chunks) { 4161 pos = 0; 4162 } 4163 if (_pool[pos]->is_tagged_free() == is_free) { 4164 return pos; 4165 } 4166 } while (pos != start); 4167 return -1; 4168 } 4169 4170 // A structure to keep information about a chunk list including which 4171 // chunks are part of this list. This is needed to keep information about a chunk list 4172 // we will to return to the ChunkManager, because the original list will be destroyed. 4173 struct AChunkList { 4174 Metachunk* head; 4175 Metachunk* all[num_chunks]; 4176 size_t size; 4177 int num; 4178 ChunkIndex index; 4179 }; 4180 4181 // Assemble, from the in-use chunks (not in the chunk manager) in the pool, 4182 // a random chunk list of max. length <list_size> of chunks with the same 4183 // ChunkIndex (chunk size). 4184 // Returns false if list cannot be assembled. List is returned in the <out> 4185 // structure. Returned list may be smaller than <list_size>. 4186 bool assemble_random_chunklist(AChunkList* out, int list_size) { 4187 // Choose a random in-use chunk from the pool... 4188 const int headpos = next_matching_chunk(get_random_position(), false); 4189 if (headpos == -1) { 4190 return false; 4191 } 4192 Metachunk* const head = _pool[headpos]; 4193 out->all[0] = head; 4194 assert(head->is_tagged_free() == false, "Chunk state mismatch"); 4195 // ..then go from there, chain it up with up to list_size - 1 number of other 4196 // in-use chunks of the same index. 4197 const ChunkIndex index = _cm.list_index(head->word_size()); 4198 int num_added = 1; 4199 size_t size_added = head->word_size(); 4200 int pos = headpos; 4201 Metachunk* tail = head; 4202 do { 4203 pos = next_matching_chunk(pos, false); 4204 if (pos != headpos) { 4205 Metachunk* c = _pool[pos]; 4206 assert(c->is_tagged_free() == false, "Chunk state mismatch"); 4207 if (index == _cm.list_index(c->word_size())) { 4208 tail->set_next(c); 4209 c->set_prev(tail); 4210 tail = c; 4211 out->all[num_added] = c; 4212 num_added ++; 4213 size_added += c->word_size(); 4214 } 4215 } 4216 } while (num_added < list_size && pos != headpos); 4217 out->head = head; 4218 out->index = index; 4219 out->size = size_added; 4220 out->num = num_added; 4221 return true; 4222 } 4223 4224 // Take a single random chunk from the ChunkManager. 4225 bool take_single_random_chunk_from_chunkmanager() { 4226 assert_counters(); 4227 _cm.locked_verify(); 4228 int pos = next_matching_chunk(get_random_position(), true); 4229 if (pos == -1) { 4230 return false; 4231 } 4232 Metachunk* c = _pool[pos]; 4233 assert(c->is_tagged_free(), "Chunk state mismatch"); 4234 // Note: instead of using ChunkManager::remove_chunk on this one chunk, we call 4235 // ChunkManager::free_chunks_get() with this chunk's word size. We really want 4236 // to exercise ChunkManager::free_chunks_get() because that one gets called for 4237 // normal chunk allocation. 4238 Metachunk* c2 = _cm.free_chunks_get(c->word_size()); 4239 assert(c2 != NULL, "Unexpected."); 4240 assert(!c2->is_tagged_free(), "Chunk state mismatch"); 4241 assert(c2->next() == NULL && c2->prev() == NULL, "Chunk should be outside of a list."); 4242 _chunks_in_chunkmanager --; 4243 _words_in_chunkmanager -= c->word_size(); 4244 assert_counters(); 4245 _cm.locked_verify(); 4246 return true; 4247 } 4248 4249 // Returns a single random chunk to the chunk manager. Returns false if that 4250 // was not possible (all chunks are already in the chunk manager). 4251 bool return_single_random_chunk_to_chunkmanager() { 4252 assert_counters(); 4253 _cm.locked_verify(); 4254 int pos = next_matching_chunk(get_random_position(), false); 4255 if (pos == -1) { 4256 return false; 4257 } 4258 Metachunk* c = _pool[pos]; 4259 assert(c->is_tagged_free() == false, "wrong chunk information"); 4260 _cm.return_single_chunk(_cm.list_index(c->word_size()), c); 4261 _chunks_in_chunkmanager ++; 4262 _words_in_chunkmanager += c->word_size(); 4263 assert(c->is_tagged_free() == true, "wrong chunk information"); 4264 assert_counters(); 4265 _cm.locked_verify(); 4266 return true; 4267 } 4268 4269 // Return a random chunk list to the chunk manager. Returns the length of the 4270 // returned list. 4271 int return_random_chunk_list_to_chunkmanager(int list_size) { 4272 assert_counters(); 4273 _cm.locked_verify(); 4274 AChunkList aChunkList; 4275 if (!assemble_random_chunklist(&aChunkList, list_size)) { 4276 return 0; 4277 } 4278 // Before returning chunks are returned, they should be tagged in use. 4279 for (int i = 0; i < aChunkList.num; i ++) { 4280 assert(!aChunkList.all[i]->is_tagged_free(), "chunk state mismatch."); 4281 } 4282 _cm.return_chunk_list(aChunkList.index, aChunkList.head); 4283 _chunks_in_chunkmanager += aChunkList.num; 4284 _words_in_chunkmanager += aChunkList.size; 4285 // After all chunks are returned, check that they are now tagged free. 4286 for (int i = 0; i < aChunkList.num; i ++) { 4287 assert(aChunkList.all[i]->is_tagged_free(), "chunk state mismatch."); 4288 } 4289 assert_counters(); 4290 _cm.locked_verify(); 4291 return aChunkList.num; 4292 } 4293 4294 public: 4295 4296 ChunkManagerReturnTestImpl() 4297 : _vsn(align_size_up(MediumChunk * num_chunks * 5 * sizeof(MetaWord), Metaspace::reserve_alignment())) 4298 , _cm(SpecializedChunk, SmallChunk, MediumChunk) 4299 , _chunks_in_chunkmanager(0) 4300 , _words_in_chunkmanager(0) 4301 { 4302 MutexLockerEx ml(SpaceManager::expand_lock(), Mutex::_no_safepoint_check_flag); 4303 // Allocate virtual space and allocate random chunks. Keep these chunks in the _pool. These chunks are 4304 // "in use", because not yet added to any chunk manager. 4305 _vsn.initialize(); 4306 _vsn.expand_by(_vsn.reserved_words(), _vsn.reserved_words()); 4307 for (int i = 0; i < num_chunks; i ++) { 4308 const size_t size = get_random_chunk_size(); 4309 _pool[i] = _vsn.get_chunk_vs(size); 4310 assert(_pool[i] != NULL, "allocation failed"); 4311 } 4312 assert_counters(); 4313 _cm.locked_verify(); 4314 } 4315 4316 // Test entry point. 4317 // Return some chunks to the chunk manager (return phase). Take some chunks out (take phase). Repeat. 4318 // Chunks are choosen randomly. Number of chunks to return or taken are choosen randomly, but affected 4319 // by the <phase_length_factor> argument: a factor of 0.0 will cause the test to quickly alternate between 4320 // returning and taking, whereas a factor of 1.0 will take/return all chunks from/to the 4321 // chunks manager, thereby emptying or filling it completely. 4322 void do_test(float phase_length_factor) { 4323 MutexLockerEx ml(SpaceManager::expand_lock(), Mutex::_no_safepoint_check_flag); 4324 assert_counters(); 4325 // Execute n operations, and operation being the move of a single chunk to/from the chunk manager. 4326 const int num_max_ops = num_chunks * 100; 4327 int num_ops = num_max_ops; 4328 const int average_phase_length = (int)(phase_length_factor * num_chunks); 4329 int num_ops_until_switch = MAX2(1, (average_phase_length + os::random() % 8 - 4)); 4330 bool return_phase = true; 4331 while (num_ops > 0) { 4332 int chunks_moved = 0; 4333 if (return_phase) { 4334 // Randomly switch between returning a single chunk or a random length chunk list. 4335 if (os::random() % 2 == 0) { 4336 if (return_single_random_chunk_to_chunkmanager()) { 4337 chunks_moved = 1; 4338 } 4339 } else { 4340 const int list_length = MAX2(1, (os::random() % num_ops_until_switch)); 4341 chunks_moved = return_random_chunk_list_to_chunkmanager(list_length); 4342 } 4343 } else { 4344 // Breath out. 4345 if (take_single_random_chunk_from_chunkmanager()) { 4346 chunks_moved = 1; 4347 } 4348 } 4349 num_ops -= chunks_moved; 4350 num_ops_until_switch -= chunks_moved; 4351 if (chunks_moved == 0 || num_ops_until_switch <= 0) { 4352 return_phase = !return_phase; 4353 num_ops_until_switch = MAX2(1, (average_phase_length + os::random() % 8 - 4)); 4354 } 4355 } 4356 } 4357 }; 4358 4359 void* setup_chunkmanager_returntests() { 4360 ChunkManagerReturnTestImpl* p = new ChunkManagerReturnTestImpl(); 4361 return p; 4362 } 4363 4364 void teardown_chunkmanager_returntests(void* p) { 4365 delete (ChunkManagerReturnTestImpl*) p; 4366 } 4367 4368 void run_chunkmanager_returntests(void* p, float phase_length) { 4369 ChunkManagerReturnTestImpl* test = (ChunkManagerReturnTestImpl*) p; 4370 test->do_test(phase_length); 4371 } 4372 4373 // The following test is placed here instead of a gtest / unittest file 4374 // because the ChunkManager class is only available in this file. 4375 class SpaceManagerTest : AllStatic { 4376 friend void SpaceManager_test_adjust_initial_chunk_size(); 4377 4378 static void test_adjust_initial_chunk_size(bool is_class) { 4379 const size_t smallest = SpaceManager::smallest_chunk_size(is_class); 4380 const size_t normal = SpaceManager::small_chunk_size(is_class); 4381 const size_t medium = SpaceManager::medium_chunk_size(is_class); 4382 4383 #define test_adjust_initial_chunk_size(value, expected, is_class_value) \ 4384 do { \ 4385 size_t v = value; \ 4386 size_t e = expected; \ 4387 assert(SpaceManager::adjust_initial_chunk_size(v, (is_class_value)) == e, \ 4388 "Expected: " SIZE_FORMAT " got: " SIZE_FORMAT, e, v); \ 4389 } while (0) 4390 4391 // Smallest (specialized) 4392 test_adjust_initial_chunk_size(1, smallest, is_class); 4393 test_adjust_initial_chunk_size(smallest - 1, smallest, is_class); 4394 test_adjust_initial_chunk_size(smallest, smallest, is_class); 4395 4396 // Small 4397 test_adjust_initial_chunk_size(smallest + 1, normal, is_class); 4398 test_adjust_initial_chunk_size(normal - 1, normal, is_class); 4399 test_adjust_initial_chunk_size(normal, normal, is_class); 4400 4401 // Medium 4402 test_adjust_initial_chunk_size(normal + 1, medium, is_class); 4403 test_adjust_initial_chunk_size(medium - 1, medium, is_class); 4404 test_adjust_initial_chunk_size(medium, medium, is_class); 4405 4406 // Humongous 4407 test_adjust_initial_chunk_size(medium + 1, medium + 1, is_class); 4408 4409 #undef test_adjust_initial_chunk_size 4410 } 4411 4412 static void test_adjust_initial_chunk_size() { 4413 test_adjust_initial_chunk_size(false); 4414 test_adjust_initial_chunk_size(true); 4415 } 4416 }; 4417 4418 void SpaceManager_test_adjust_initial_chunk_size() { 4419 SpaceManagerTest::test_adjust_initial_chunk_size(); 4420 } 4421 4422 #endif // ASSERT