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 "logging/logStream.hpp" 31 #include "memory/allocation.hpp" 32 #include "memory/binaryTreeDictionary.hpp" 33 #include "memory/filemap.hpp" 34 #include "memory/freeList.hpp" 35 #include "memory/metachunk.hpp" 36 #include "memory/metaspace.hpp" 37 #include "memory/metaspaceGCThresholdUpdater.hpp" 38 #include "memory/metaspaceShared.hpp" 39 #include "memory/metaspaceTracer.hpp" 40 #include "memory/resourceArea.hpp" 41 #include "memory/universe.hpp" 42 #include "runtime/atomic.hpp" 43 #include "runtime/globals.hpp" 44 #include "runtime/init.hpp" 45 #include "runtime/java.hpp" 46 #include "runtime/mutex.hpp" 47 #include "runtime/orderAccess.inline.hpp" 48 #include "services/memTracker.hpp" 49 #include "services/memoryService.hpp" 50 #include "utilities/copy.hpp" 51 #include "utilities/debug.hpp" 52 #include "utilities/macros.hpp" 53 54 typedef BinaryTreeDictionary<Metablock, FreeList<Metablock> > BlockTreeDictionary; 55 typedef BinaryTreeDictionary<Metachunk, FreeList<Metachunk> > ChunkTreeDictionary; 56 57 // Set this constant to enable slow integrity checking of the free chunk lists 58 const bool metaspace_slow_verify = false; 59 60 size_t const allocation_from_dictionary_limit = 4 * K; 61 62 MetaWord* last_allocated = 0; 63 64 size_t Metaspace::_compressed_class_space_size; 65 const MetaspaceTracer* Metaspace::_tracer = NULL; 66 67 // Used in declarations in SpaceManager and ChunkManager 68 enum ChunkIndex { 69 ZeroIndex = 0, 70 SpecializedIndex = ZeroIndex, 71 SmallIndex = SpecializedIndex + 1, 72 MediumIndex = SmallIndex + 1, 73 HumongousIndex = MediumIndex + 1, 74 NumberOfFreeLists = 3, 75 NumberOfInUseLists = 4 76 }; 77 78 // Helper, returns a descriptive name for the given index. 79 static const char* chunk_size_name(ChunkIndex index) { 80 switch (index) { 81 case SpecializedIndex: 82 return "specialized"; 83 case SmallIndex: 84 return "small"; 85 case MediumIndex: 86 return "medium"; 87 case HumongousIndex: 88 return "humongous"; 89 default: 90 return "Invalid index"; 91 } 92 } 93 94 enum ChunkSizes { // in words. 95 ClassSpecializedChunk = 128, 96 SpecializedChunk = 128, 97 ClassSmallChunk = 256, 98 SmallChunk = 512, 99 ClassMediumChunk = 4 * K, 100 MediumChunk = 8 * K 101 }; 102 103 static ChunkIndex next_chunk_index(ChunkIndex i) { 104 assert(i < NumberOfInUseLists, "Out of bound"); 105 return (ChunkIndex) (i+1); 106 } 107 108 volatile intptr_t MetaspaceGC::_capacity_until_GC = 0; 109 uint MetaspaceGC::_shrink_factor = 0; 110 bool MetaspaceGC::_should_concurrent_collect = false; 111 112 typedef class FreeList<Metachunk> ChunkList; 113 114 // Manages the global free lists of chunks. 115 class ChunkManager : public CHeapObj<mtInternal> { 116 friend class TestVirtualSpaceNodeTest; 117 118 // Free list of chunks of different sizes. 119 // SpecializedChunk 120 // SmallChunk 121 // MediumChunk 122 ChunkList _free_chunks[NumberOfFreeLists]; 123 124 // Return non-humongous chunk list by its index. 125 ChunkList* free_chunks(ChunkIndex index); 126 127 // Returns non-humongous chunk list for the given chunk word size. 128 ChunkList* find_free_chunks_list(size_t word_size); 129 130 // HumongousChunk 131 ChunkTreeDictionary _humongous_dictionary; 132 133 // Returns the humongous chunk dictionary. 134 ChunkTreeDictionary* humongous_dictionary() { 135 return &_humongous_dictionary; 136 } 137 138 // Size, in metaspace words, of all chunks managed by this ChunkManager 139 size_t _free_chunks_total; 140 // Number of chunks in this ChunkManager 141 size_t _free_chunks_count; 142 143 // Update counters after a chunk was added or removed removed. 144 void account_for_added_chunk(const Metachunk* c); 145 void account_for_removed_chunk(const Metachunk* c); 146 147 // Debug support 148 149 size_t sum_free_chunks(); 150 size_t sum_free_chunks_count(); 151 152 void locked_verify_free_chunks_total(); 153 void slow_locked_verify_free_chunks_total() { 154 if (metaspace_slow_verify) { 155 locked_verify_free_chunks_total(); 156 } 157 } 158 void locked_verify_free_chunks_count(); 159 void slow_locked_verify_free_chunks_count() { 160 if (metaspace_slow_verify) { 161 locked_verify_free_chunks_count(); 162 } 163 } 164 void verify_free_chunks_count(); 165 166 public: 167 168 ChunkManager(size_t specialized_size, size_t small_size, size_t medium_size) 169 : _free_chunks_total(0), _free_chunks_count(0) { 170 _free_chunks[SpecializedIndex].set_size(specialized_size); 171 _free_chunks[SmallIndex].set_size(small_size); 172 _free_chunks[MediumIndex].set_size(medium_size); 173 } 174 175 // add or delete (return) a chunk to the global freelist. 176 Metachunk* chunk_freelist_allocate(size_t word_size); 177 178 // Map a size to a list index assuming that there are lists 179 // for special, small, medium, and humongous chunks. 180 ChunkIndex list_index(size_t size); 181 182 // Map a given index to the chunk size. 183 size_t size_by_index(ChunkIndex index); 184 185 // Take a chunk from the ChunkManager. The chunk is expected to be in 186 // the chunk manager (the freelist if non-humongous, the dictionary if 187 // humongous). 188 void remove_chunk(Metachunk* chunk); 189 190 // Return a single chunk of type index to the ChunkManager. 191 void return_single_chunk(ChunkIndex index, Metachunk* chunk); 192 193 // Add the simple linked list of chunks to the freelist of chunks 194 // of type index. 195 void return_chunk_list(ChunkIndex index, Metachunk* chunk); 196 197 // Total of the space in the free chunks list 198 size_t free_chunks_total_words(); 199 size_t free_chunks_total_bytes(); 200 201 // Number of chunks in the free chunks list 202 size_t free_chunks_count(); 203 204 // Remove from a list by size. Selects list based on size of chunk. 205 Metachunk* free_chunks_get(size_t chunk_word_size); 206 207 #define index_bounds_check(index) \ 208 assert(index == SpecializedIndex || \ 209 index == SmallIndex || \ 210 index == MediumIndex || \ 211 index == HumongousIndex, "Bad index: %d", (int) index) 212 213 size_t num_free_chunks(ChunkIndex index) const { 214 index_bounds_check(index); 215 216 if (index == HumongousIndex) { 217 return _humongous_dictionary.total_free_blocks(); 218 } 219 220 ssize_t count = _free_chunks[index].count(); 221 return count == -1 ? 0 : (size_t) count; 222 } 223 224 size_t size_free_chunks_in_bytes(ChunkIndex index) const { 225 index_bounds_check(index); 226 227 size_t word_size = 0; 228 if (index == HumongousIndex) { 229 word_size = _humongous_dictionary.total_size(); 230 } else { 231 const size_t size_per_chunk_in_words = _free_chunks[index].size(); 232 word_size = size_per_chunk_in_words * num_free_chunks(index); 233 } 234 235 return word_size * BytesPerWord; 236 } 237 238 MetaspaceChunkFreeListSummary chunk_free_list_summary() const { 239 return MetaspaceChunkFreeListSummary(num_free_chunks(SpecializedIndex), 240 num_free_chunks(SmallIndex), 241 num_free_chunks(MediumIndex), 242 num_free_chunks(HumongousIndex), 243 size_free_chunks_in_bytes(SpecializedIndex), 244 size_free_chunks_in_bytes(SmallIndex), 245 size_free_chunks_in_bytes(MediumIndex), 246 size_free_chunks_in_bytes(HumongousIndex)); 247 } 248 249 // Debug support 250 void verify(); 251 void slow_verify() { 252 if (metaspace_slow_verify) { 253 verify(); 254 } 255 } 256 void locked_verify(); 257 void slow_locked_verify() { 258 if (metaspace_slow_verify) { 259 locked_verify(); 260 } 261 } 262 void verify_free_chunks_total(); 263 264 void locked_print_free_chunks(outputStream* st); 265 void locked_print_sum_free_chunks(outputStream* st); 266 267 void print_on(outputStream* st) const; 268 }; 269 270 class SmallBlocks : public CHeapObj<mtClass> { 271 const static uint _small_block_max_size = sizeof(TreeChunk<Metablock, FreeList<Metablock> >)/HeapWordSize; 272 const static uint _small_block_min_size = sizeof(Metablock)/HeapWordSize; 273 274 private: 275 FreeList<Metablock> _small_lists[_small_block_max_size - _small_block_min_size]; 276 277 FreeList<Metablock>& list_at(size_t word_size) { 278 assert(word_size >= _small_block_min_size, "There are no metaspace objects less than %u words", _small_block_min_size); 279 return _small_lists[word_size - _small_block_min_size]; 280 } 281 282 public: 283 SmallBlocks() { 284 for (uint i = _small_block_min_size; i < _small_block_max_size; i++) { 285 uint k = i - _small_block_min_size; 286 _small_lists[k].set_size(i); 287 } 288 } 289 290 size_t total_size() const { 291 size_t result = 0; 292 for (uint i = _small_block_min_size; i < _small_block_max_size; i++) { 293 uint k = i - _small_block_min_size; 294 result = result + _small_lists[k].count() * _small_lists[k].size(); 295 } 296 return result; 297 } 298 299 static uint small_block_max_size() { return _small_block_max_size; } 300 static uint small_block_min_size() { return _small_block_min_size; } 301 302 MetaWord* get_block(size_t word_size) { 303 if (list_at(word_size).count() > 0) { 304 MetaWord* new_block = (MetaWord*) list_at(word_size).get_chunk_at_head(); 305 return new_block; 306 } else { 307 return NULL; 308 } 309 } 310 void return_block(Metablock* free_chunk, size_t word_size) { 311 list_at(word_size).return_chunk_at_head(free_chunk, false); 312 assert(list_at(word_size).count() > 0, "Should have a chunk"); 313 } 314 315 void print_on(outputStream* st) const { 316 st->print_cr("SmallBlocks:"); 317 for (uint i = _small_block_min_size; i < _small_block_max_size; i++) { 318 uint k = i - _small_block_min_size; 319 st->print_cr("small_lists size " SIZE_FORMAT " count " SIZE_FORMAT, _small_lists[k].size(), _small_lists[k].count()); 320 } 321 } 322 }; 323 324 // Used to manage the free list of Metablocks (a block corresponds 325 // to the allocation of a quantum of metadata). 326 class BlockFreelist : public CHeapObj<mtClass> { 327 BlockTreeDictionary* const _dictionary; 328 SmallBlocks* _small_blocks; 329 330 // Only allocate and split from freelist if the size of the allocation 331 // is at least 1/4th the size of the available block. 332 const static int WasteMultiplier = 4; 333 334 // Accessors 335 BlockTreeDictionary* dictionary() const { return _dictionary; } 336 SmallBlocks* small_blocks() { 337 if (_small_blocks == NULL) { 338 _small_blocks = new SmallBlocks(); 339 } 340 return _small_blocks; 341 } 342 343 public: 344 BlockFreelist(); 345 ~BlockFreelist(); 346 347 // Get and return a block to the free list 348 MetaWord* get_block(size_t word_size); 349 void return_block(MetaWord* p, size_t word_size); 350 351 size_t total_size() const { 352 size_t result = dictionary()->total_size(); 353 if (_small_blocks != NULL) { 354 result = result + _small_blocks->total_size(); 355 } 356 return result; 357 } 358 359 static size_t min_dictionary_size() { return TreeChunk<Metablock, FreeList<Metablock> >::min_size(); } 360 void print_on(outputStream* st) const; 361 }; 362 363 // A VirtualSpaceList node. 364 class VirtualSpaceNode : public CHeapObj<mtClass> { 365 friend class VirtualSpaceList; 366 367 // Link to next VirtualSpaceNode 368 VirtualSpaceNode* _next; 369 370 // total in the VirtualSpace 371 MemRegion _reserved; 372 ReservedSpace _rs; 373 VirtualSpace _virtual_space; 374 MetaWord* _top; 375 // count of chunks contained in this VirtualSpace 376 uintx _container_count; 377 378 // Convenience functions to access the _virtual_space 379 char* low() const { return virtual_space()->low(); } 380 char* high() const { return virtual_space()->high(); } 381 382 // The first Metachunk will be allocated at the bottom of the 383 // VirtualSpace 384 Metachunk* first_chunk() { return (Metachunk*) bottom(); } 385 386 // Committed but unused space in the virtual space 387 size_t free_words_in_vs() const; 388 public: 389 390 VirtualSpaceNode(size_t byte_size); 391 VirtualSpaceNode(ReservedSpace rs) : _top(NULL), _next(NULL), _rs(rs), _container_count(0) {} 392 ~VirtualSpaceNode(); 393 394 // Convenience functions for logical bottom and end 395 MetaWord* bottom() const { return (MetaWord*) _virtual_space.low(); } 396 MetaWord* end() const { return (MetaWord*) _virtual_space.high(); } 397 398 bool contains(const void* ptr) { return ptr >= low() && ptr < high(); } 399 400 size_t reserved_words() const { return _virtual_space.reserved_size() / BytesPerWord; } 401 size_t committed_words() const { return _virtual_space.actual_committed_size() / BytesPerWord; } 402 403 bool is_pre_committed() const { return _virtual_space.special(); } 404 405 // address of next available space in _virtual_space; 406 // Accessors 407 VirtualSpaceNode* next() { return _next; } 408 void set_next(VirtualSpaceNode* v) { _next = v; } 409 410 void set_reserved(MemRegion const v) { _reserved = v; } 411 void set_top(MetaWord* v) { _top = v; } 412 413 // Accessors 414 MemRegion* reserved() { return &_reserved; } 415 VirtualSpace* virtual_space() const { return (VirtualSpace*) &_virtual_space; } 416 417 // Returns true if "word_size" is available in the VirtualSpace 418 bool is_available(size_t word_size) { return word_size <= pointer_delta(end(), _top, sizeof(MetaWord)); } 419 420 MetaWord* top() const { return _top; } 421 void inc_top(size_t word_size) { _top += word_size; } 422 423 uintx container_count() { return _container_count; } 424 void inc_container_count(); 425 void dec_container_count(); 426 #ifdef ASSERT 427 uintx container_count_slow(); 428 void verify_container_count(); 429 #endif 430 431 // used and capacity in this single entry in the list 432 size_t used_words_in_vs() const; 433 size_t capacity_words_in_vs() const; 434 435 bool initialize(); 436 437 // get space from the virtual space 438 Metachunk* take_from_committed(size_t chunk_word_size); 439 440 // Allocate a chunk from the virtual space and return it. 441 Metachunk* get_chunk_vs(size_t chunk_word_size); 442 443 // Expands/shrinks the committed space in a virtual space. Delegates 444 // to Virtualspace 445 bool expand_by(size_t min_words, size_t preferred_words); 446 447 // In preparation for deleting this node, remove all the chunks 448 // in the node from any freelist. 449 void purge(ChunkManager* chunk_manager); 450 451 // If an allocation doesn't fit in the current node a new node is created. 452 // Allocate chunks out of the remaining committed space in this node 453 // to avoid wasting that memory. 454 // This always adds up because all the chunk sizes are multiples of 455 // the smallest chunk size. 456 void retire(ChunkManager* chunk_manager); 457 458 #ifdef ASSERT 459 // Debug support 460 void mangle(); 461 #endif 462 463 void print_on(outputStream* st) const; 464 }; 465 466 #define assert_is_ptr_aligned(ptr, alignment) \ 467 assert(is_ptr_aligned(ptr, alignment), \ 468 PTR_FORMAT " is not aligned to " \ 469 SIZE_FORMAT, p2i(ptr), alignment) 470 471 #define assert_is_size_aligned(size, alignment) \ 472 assert(is_size_aligned(size, alignment), \ 473 SIZE_FORMAT " is not aligned to " \ 474 SIZE_FORMAT, size, alignment) 475 476 477 // Decide if large pages should be committed when the memory is reserved. 478 static bool should_commit_large_pages_when_reserving(size_t bytes) { 479 if (UseLargePages && UseLargePagesInMetaspace && !os::can_commit_large_page_memory()) { 480 size_t words = bytes / BytesPerWord; 481 bool is_class = false; // We never reserve large pages for the class space. 482 if (MetaspaceGC::can_expand(words, is_class) && 483 MetaspaceGC::allowed_expansion() >= words) { 484 return true; 485 } 486 } 487 488 return false; 489 } 490 491 // byte_size is the size of the associated virtualspace. 492 VirtualSpaceNode::VirtualSpaceNode(size_t bytes) : _top(NULL), _next(NULL), _rs(), _container_count(0) { 493 assert_is_size_aligned(bytes, Metaspace::reserve_alignment()); 494 495 #if INCLUDE_CDS 496 // This allocates memory with mmap. For DumpSharedspaces, try to reserve 497 // configurable address, generally at the top of the Java heap so other 498 // memory addresses don't conflict. 499 if (DumpSharedSpaces) { 500 bool large_pages = false; // No large pages when dumping the CDS archive. 501 char* shared_base = (char*)align_ptr_up((char*)SharedBaseAddress, Metaspace::reserve_alignment()); 502 503 _rs = ReservedSpace(bytes, Metaspace::reserve_alignment(), large_pages, shared_base); 504 if (_rs.is_reserved()) { 505 assert(shared_base == 0 || _rs.base() == shared_base, "should match"); 506 } else { 507 // Get a mmap region anywhere if the SharedBaseAddress fails. 508 _rs = ReservedSpace(bytes, Metaspace::reserve_alignment(), large_pages); 509 } 510 if (!_rs.is_reserved()) { 511 vm_exit_during_initialization("Unable to allocate memory for shared space", 512 err_msg(SIZE_FORMAT " bytes.", bytes)); 513 } 514 MetaspaceShared::initialize_shared_rs(&_rs); 515 } else 516 #endif 517 { 518 bool large_pages = should_commit_large_pages_when_reserving(bytes); 519 520 _rs = ReservedSpace(bytes, Metaspace::reserve_alignment(), large_pages); 521 } 522 523 if (_rs.is_reserved()) { 524 assert(_rs.base() != NULL, "Catch if we get a NULL address"); 525 assert(_rs.size() != 0, "Catch if we get a 0 size"); 526 assert_is_ptr_aligned(_rs.base(), Metaspace::reserve_alignment()); 527 assert_is_size_aligned(_rs.size(), Metaspace::reserve_alignment()); 528 529 MemTracker::record_virtual_memory_type((address)_rs.base(), mtClass); 530 } 531 } 532 533 void VirtualSpaceNode::purge(ChunkManager* chunk_manager) { 534 Metachunk* chunk = first_chunk(); 535 Metachunk* invalid_chunk = (Metachunk*) top(); 536 while (chunk < invalid_chunk ) { 537 assert(chunk->is_tagged_free(), "Should be tagged free"); 538 MetaWord* next = ((MetaWord*)chunk) + chunk->word_size(); 539 chunk_manager->remove_chunk(chunk); 540 assert(chunk->next() == NULL && 541 chunk->prev() == NULL, 542 "Was not removed from its list"); 543 chunk = (Metachunk*) next; 544 } 545 } 546 547 #ifdef ASSERT 548 uintx VirtualSpaceNode::container_count_slow() { 549 uintx count = 0; 550 Metachunk* chunk = first_chunk(); 551 Metachunk* invalid_chunk = (Metachunk*) top(); 552 while (chunk < invalid_chunk ) { 553 MetaWord* next = ((MetaWord*)chunk) + chunk->word_size(); 554 // Don't count the chunks on the free lists. Those are 555 // still part of the VirtualSpaceNode but not currently 556 // counted. 557 if (!chunk->is_tagged_free()) { 558 count++; 559 } 560 chunk = (Metachunk*) next; 561 } 562 return count; 563 } 564 #endif 565 566 // List of VirtualSpaces for metadata allocation. 567 class VirtualSpaceList : public CHeapObj<mtClass> { 568 friend class VirtualSpaceNode; 569 570 enum VirtualSpaceSizes { 571 VirtualSpaceSize = 256 * K 572 }; 573 574 // Head of the list 575 VirtualSpaceNode* _virtual_space_list; 576 // virtual space currently being used for allocations 577 VirtualSpaceNode* _current_virtual_space; 578 579 // Is this VirtualSpaceList used for the compressed class space 580 bool _is_class; 581 582 // Sum of reserved and committed memory in the virtual spaces 583 size_t _reserved_words; 584 size_t _committed_words; 585 586 // Number of virtual spaces 587 size_t _virtual_space_count; 588 589 ~VirtualSpaceList(); 590 591 VirtualSpaceNode* virtual_space_list() const { return _virtual_space_list; } 592 593 void set_virtual_space_list(VirtualSpaceNode* v) { 594 _virtual_space_list = v; 595 } 596 void set_current_virtual_space(VirtualSpaceNode* v) { 597 _current_virtual_space = v; 598 } 599 600 void link_vs(VirtualSpaceNode* new_entry); 601 602 // Get another virtual space and add it to the list. This 603 // is typically prompted by a failed attempt to allocate a chunk 604 // and is typically followed by the allocation of a chunk. 605 bool create_new_virtual_space(size_t vs_word_size); 606 607 // Chunk up the unused committed space in the current 608 // virtual space and add the chunks to the free list. 609 void retire_current_virtual_space(); 610 611 public: 612 VirtualSpaceList(size_t word_size); 613 VirtualSpaceList(ReservedSpace rs); 614 615 size_t free_bytes(); 616 617 Metachunk* get_new_chunk(size_t chunk_word_size, 618 size_t suggested_commit_granularity); 619 620 bool expand_node_by(VirtualSpaceNode* node, 621 size_t min_words, 622 size_t preferred_words); 623 624 bool expand_by(size_t min_words, 625 size_t preferred_words); 626 627 VirtualSpaceNode* current_virtual_space() { 628 return _current_virtual_space; 629 } 630 631 bool is_class() const { return _is_class; } 632 633 bool initialization_succeeded() { return _virtual_space_list != NULL; } 634 635 size_t reserved_words() { return _reserved_words; } 636 size_t reserved_bytes() { return reserved_words() * BytesPerWord; } 637 size_t committed_words() { return _committed_words; } 638 size_t committed_bytes() { return committed_words() * BytesPerWord; } 639 640 void inc_reserved_words(size_t v); 641 void dec_reserved_words(size_t v); 642 void inc_committed_words(size_t v); 643 void dec_committed_words(size_t v); 644 void inc_virtual_space_count(); 645 void dec_virtual_space_count(); 646 647 bool contains(const void* ptr); 648 649 // Unlink empty VirtualSpaceNodes and free it. 650 void purge(ChunkManager* chunk_manager); 651 652 void print_on(outputStream* st) const; 653 654 class VirtualSpaceListIterator : public StackObj { 655 VirtualSpaceNode* _virtual_spaces; 656 public: 657 VirtualSpaceListIterator(VirtualSpaceNode* virtual_spaces) : 658 _virtual_spaces(virtual_spaces) {} 659 660 bool repeat() { 661 return _virtual_spaces != NULL; 662 } 663 664 VirtualSpaceNode* get_next() { 665 VirtualSpaceNode* result = _virtual_spaces; 666 if (_virtual_spaces != NULL) { 667 _virtual_spaces = _virtual_spaces->next(); 668 } 669 return result; 670 } 671 }; 672 }; 673 674 class Metadebug : AllStatic { 675 // Debugging support for Metaspaces 676 static int _allocation_fail_alot_count; 677 678 public: 679 680 static void init_allocation_fail_alot_count(); 681 #ifdef ASSERT 682 static bool test_metadata_failure(); 683 #endif 684 }; 685 686 int Metadebug::_allocation_fail_alot_count = 0; 687 688 // SpaceManager - used by Metaspace to handle allocations 689 class SpaceManager : public CHeapObj<mtClass> { 690 friend class Metaspace; 691 friend class Metadebug; 692 693 private: 694 695 // protects allocations 696 Mutex* const _lock; 697 698 // Type of metadata allocated. 699 Metaspace::MetadataType _mdtype; 700 701 // List of chunks in use by this SpaceManager. Allocations 702 // are done from the current chunk. The list is used for deallocating 703 // chunks when the SpaceManager is freed. 704 Metachunk* _chunks_in_use[NumberOfInUseLists]; 705 Metachunk* _current_chunk; 706 707 // Maximum number of small chunks to allocate to a SpaceManager 708 static uint const _small_chunk_limit; 709 710 // Sum of all space in allocated chunks 711 size_t _allocated_blocks_words; 712 713 // Sum of all allocated chunks 714 size_t _allocated_chunks_words; 715 size_t _allocated_chunks_count; 716 717 // Free lists of blocks are per SpaceManager since they 718 // are assumed to be in chunks in use by the SpaceManager 719 // and all chunks in use by a SpaceManager are freed when 720 // the class loader using the SpaceManager is collected. 721 BlockFreelist* _block_freelists; 722 723 // protects virtualspace and chunk expansions 724 static const char* _expand_lock_name; 725 static const int _expand_lock_rank; 726 static Mutex* const _expand_lock; 727 728 private: 729 // Accessors 730 Metachunk* chunks_in_use(ChunkIndex index) const { return _chunks_in_use[index]; } 731 void set_chunks_in_use(ChunkIndex index, Metachunk* v) { 732 _chunks_in_use[index] = v; 733 } 734 735 BlockFreelist* block_freelists() const { return _block_freelists; } 736 737 Metaspace::MetadataType mdtype() { return _mdtype; } 738 739 VirtualSpaceList* vs_list() const { return Metaspace::get_space_list(_mdtype); } 740 ChunkManager* chunk_manager() const { return Metaspace::get_chunk_manager(_mdtype); } 741 742 Metachunk* current_chunk() const { return _current_chunk; } 743 void set_current_chunk(Metachunk* v) { 744 _current_chunk = v; 745 } 746 747 Metachunk* find_current_chunk(size_t word_size); 748 749 // Add chunk to the list of chunks in use 750 void add_chunk(Metachunk* v, bool make_current); 751 void retire_current_chunk(); 752 753 Mutex* lock() const { return _lock; } 754 755 protected: 756 void initialize(); 757 758 public: 759 SpaceManager(Metaspace::MetadataType mdtype, 760 Mutex* lock); 761 ~SpaceManager(); 762 763 enum ChunkMultiples { 764 MediumChunkMultiple = 4 765 }; 766 767 static size_t specialized_chunk_size(bool is_class) { return is_class ? ClassSpecializedChunk : SpecializedChunk; } 768 static size_t small_chunk_size(bool is_class) { return is_class ? ClassSmallChunk : SmallChunk; } 769 static size_t medium_chunk_size(bool is_class) { return is_class ? ClassMediumChunk : MediumChunk; } 770 771 static size_t smallest_chunk_size(bool is_class) { return specialized_chunk_size(is_class); } 772 773 // Accessors 774 bool is_class() const { return _mdtype == Metaspace::ClassType; } 775 776 size_t specialized_chunk_size() const { return specialized_chunk_size(is_class()); } 777 size_t small_chunk_size() const { return small_chunk_size(is_class()); } 778 size_t medium_chunk_size() const { return medium_chunk_size(is_class()); } 779 780 size_t smallest_chunk_size() const { return smallest_chunk_size(is_class()); } 781 782 size_t medium_chunk_bunch() const { return medium_chunk_size() * MediumChunkMultiple; } 783 784 size_t allocated_blocks_words() const { return _allocated_blocks_words; } 785 size_t allocated_blocks_bytes() const { return _allocated_blocks_words * BytesPerWord; } 786 size_t allocated_chunks_words() const { return _allocated_chunks_words; } 787 size_t allocated_chunks_bytes() const { return _allocated_chunks_words * BytesPerWord; } 788 size_t allocated_chunks_count() const { return _allocated_chunks_count; } 789 790 bool is_humongous(size_t word_size) { return word_size > medium_chunk_size(); } 791 792 static Mutex* expand_lock() { return _expand_lock; } 793 794 // Increment the per Metaspace and global running sums for Metachunks 795 // by the given size. This is used when a Metachunk to added to 796 // the in-use list. 797 void inc_size_metrics(size_t words); 798 // Increment the per Metaspace and global running sums Metablocks by the given 799 // size. This is used when a Metablock is allocated. 800 void inc_used_metrics(size_t words); 801 // Delete the portion of the running sums for this SpaceManager. That is, 802 // the globals running sums for the Metachunks and Metablocks are 803 // decremented for all the Metachunks in-use by this SpaceManager. 804 void dec_total_from_size_metrics(); 805 806 // Adjust the initial chunk size to match one of the fixed chunk list sizes, 807 // or return the unadjusted size if the requested size is humongous. 808 static size_t adjust_initial_chunk_size(size_t requested, bool is_class_space); 809 size_t adjust_initial_chunk_size(size_t requested) const; 810 811 // Get the initial chunks size for this metaspace type. 812 size_t get_initial_chunk_size(Metaspace::MetaspaceType type) const; 813 814 size_t sum_capacity_in_chunks_in_use() const; 815 size_t sum_used_in_chunks_in_use() const; 816 size_t sum_free_in_chunks_in_use() const; 817 size_t sum_waste_in_chunks_in_use() const; 818 size_t sum_waste_in_chunks_in_use(ChunkIndex index ) const; 819 820 size_t sum_count_in_chunks_in_use(); 821 size_t sum_count_in_chunks_in_use(ChunkIndex i); 822 823 Metachunk* get_new_chunk(size_t chunk_word_size); 824 825 // Block allocation and deallocation. 826 // Allocates a block from the current chunk 827 MetaWord* allocate(size_t word_size); 828 // Allocates a block from a small chunk 829 MetaWord* get_small_chunk_and_allocate(size_t word_size); 830 831 // Helper for allocations 832 MetaWord* allocate_work(size_t word_size); 833 834 // Returns a block to the per manager freelist 835 void deallocate(MetaWord* p, size_t word_size); 836 837 // Based on the allocation size and a minimum chunk size, 838 // returned chunk size (for expanding space for chunk allocation). 839 size_t calc_chunk_size(size_t allocation_word_size); 840 841 // Called when an allocation from the current chunk fails. 842 // Gets a new chunk (may require getting a new virtual space), 843 // and allocates from that chunk. 844 MetaWord* grow_and_allocate(size_t word_size); 845 846 // Notify memory usage to MemoryService. 847 void track_metaspace_memory_usage(); 848 849 // debugging support. 850 851 void dump(outputStream* const out) const; 852 void print_on(outputStream* st) const; 853 void locked_print_chunks_in_use_on(outputStream* st) const; 854 855 void verify(); 856 void verify_chunk_size(Metachunk* chunk); 857 #ifdef ASSERT 858 void verify_allocated_blocks_words(); 859 #endif 860 861 // This adjusts the size given to be greater than the minimum allocation size in 862 // words for data in metaspace. Esentially the minimum size is currently 3 words. 863 size_t get_allocation_word_size(size_t word_size) { 864 size_t byte_size = word_size * BytesPerWord; 865 866 size_t raw_bytes_size = MAX2(byte_size, sizeof(Metablock)); 867 raw_bytes_size = align_size_up(raw_bytes_size, Metachunk::object_alignment()); 868 869 size_t raw_word_size = raw_bytes_size / BytesPerWord; 870 assert(raw_word_size * BytesPerWord == raw_bytes_size, "Size problem"); 871 872 return raw_word_size; 873 } 874 }; 875 876 uint const SpaceManager::_small_chunk_limit = 4; 877 878 const char* SpaceManager::_expand_lock_name = 879 "SpaceManager chunk allocation lock"; 880 const int SpaceManager::_expand_lock_rank = Monitor::leaf - 1; 881 Mutex* const SpaceManager::_expand_lock = 882 new Mutex(SpaceManager::_expand_lock_rank, 883 SpaceManager::_expand_lock_name, 884 Mutex::_allow_vm_block_flag, 885 Monitor::_safepoint_check_never); 886 887 void VirtualSpaceNode::inc_container_count() { 888 assert_lock_strong(SpaceManager::expand_lock()); 889 _container_count++; 890 } 891 892 void VirtualSpaceNode::dec_container_count() { 893 assert_lock_strong(SpaceManager::expand_lock()); 894 _container_count--; 895 } 896 897 #ifdef ASSERT 898 void VirtualSpaceNode::verify_container_count() { 899 assert(_container_count == container_count_slow(), 900 "Inconsistency in container_count _container_count " UINTX_FORMAT 901 " container_count_slow() " UINTX_FORMAT, _container_count, container_count_slow()); 902 } 903 #endif 904 905 // BlockFreelist methods 906 907 BlockFreelist::BlockFreelist() : _dictionary(new BlockTreeDictionary()), _small_blocks(NULL) {} 908 909 BlockFreelist::~BlockFreelist() { 910 delete _dictionary; 911 if (_small_blocks != NULL) { 912 delete _small_blocks; 913 } 914 } 915 916 void BlockFreelist::return_block(MetaWord* p, size_t word_size) { 917 assert(word_size >= SmallBlocks::small_block_min_size(), "never return dark matter"); 918 919 Metablock* free_chunk = ::new (p) Metablock(word_size); 920 if (word_size < SmallBlocks::small_block_max_size()) { 921 small_blocks()->return_block(free_chunk, word_size); 922 } else { 923 dictionary()->return_chunk(free_chunk); 924 } 925 log_trace(gc, metaspace, freelist, blocks)("returning block at " INTPTR_FORMAT " size = " 926 SIZE_FORMAT, p2i(free_chunk), word_size); 927 } 928 929 MetaWord* BlockFreelist::get_block(size_t word_size) { 930 assert(word_size >= SmallBlocks::small_block_min_size(), "never get dark matter"); 931 932 // Try small_blocks first. 933 if (word_size < SmallBlocks::small_block_max_size()) { 934 // Don't create small_blocks() until needed. small_blocks() allocates the small block list for 935 // this space manager. 936 MetaWord* new_block = (MetaWord*) small_blocks()->get_block(word_size); 937 if (new_block != NULL) { 938 log_trace(gc, metaspace, freelist, blocks)("getting block at " INTPTR_FORMAT " size = " SIZE_FORMAT, 939 p2i(new_block), word_size); 940 return new_block; 941 } 942 } 943 944 if (word_size < BlockFreelist::min_dictionary_size()) { 945 // If allocation in small blocks fails, this is Dark Matter. Too small for dictionary. 946 return NULL; 947 } 948 949 Metablock* free_block = 950 dictionary()->get_chunk(word_size, FreeBlockDictionary<Metablock>::atLeast); 951 if (free_block == NULL) { 952 return NULL; 953 } 954 955 const size_t block_size = free_block->size(); 956 if (block_size > WasteMultiplier * word_size) { 957 return_block((MetaWord*)free_block, block_size); 958 return NULL; 959 } 960 961 MetaWord* new_block = (MetaWord*)free_block; 962 assert(block_size >= word_size, "Incorrect size of block from freelist"); 963 const size_t unused = block_size - word_size; 964 if (unused >= SmallBlocks::small_block_min_size()) { 965 return_block(new_block + word_size, unused); 966 } 967 968 log_trace(gc, metaspace, freelist, blocks)("getting block at " INTPTR_FORMAT " size = " SIZE_FORMAT, 969 p2i(new_block), word_size); 970 return new_block; 971 } 972 973 void BlockFreelist::print_on(outputStream* st) const { 974 dictionary()->print_free_lists(st); 975 if (_small_blocks != NULL) { 976 _small_blocks->print_on(st); 977 } 978 } 979 980 // VirtualSpaceNode methods 981 982 VirtualSpaceNode::~VirtualSpaceNode() { 983 _rs.release(); 984 #ifdef ASSERT 985 size_t word_size = sizeof(*this) / BytesPerWord; 986 Copy::fill_to_words((HeapWord*) this, word_size, 0xf1f1f1f1); 987 #endif 988 } 989 990 size_t VirtualSpaceNode::used_words_in_vs() const { 991 return pointer_delta(top(), bottom(), sizeof(MetaWord)); 992 } 993 994 // Space committed in the VirtualSpace 995 size_t VirtualSpaceNode::capacity_words_in_vs() const { 996 return pointer_delta(end(), bottom(), sizeof(MetaWord)); 997 } 998 999 size_t VirtualSpaceNode::free_words_in_vs() const { 1000 return pointer_delta(end(), top(), sizeof(MetaWord)); 1001 } 1002 1003 // Allocates the chunk from the virtual space only. 1004 // This interface is also used internally for debugging. Not all 1005 // chunks removed here are necessarily used for allocation. 1006 Metachunk* VirtualSpaceNode::take_from_committed(size_t chunk_word_size) { 1007 // Bottom of the new chunk 1008 MetaWord* chunk_limit = top(); 1009 assert(chunk_limit != NULL, "Not safe to call this method"); 1010 1011 // The virtual spaces are always expanded by the 1012 // commit granularity to enforce the following condition. 1013 // Without this the is_available check will not work correctly. 1014 assert(_virtual_space.committed_size() == _virtual_space.actual_committed_size(), 1015 "The committed memory doesn't match the expanded memory."); 1016 1017 if (!is_available(chunk_word_size)) { 1018 LogTarget(Debug, gc, metaspace, freelist) lt; 1019 if (lt.is_enabled()) { 1020 LogStream ls(lt); 1021 ls.print("VirtualSpaceNode::take_from_committed() not available " SIZE_FORMAT " words ", chunk_word_size); 1022 // Dump some information about the virtual space that is nearly full 1023 print_on(&ls); 1024 } 1025 return NULL; 1026 } 1027 1028 // Take the space (bump top on the current virtual space). 1029 inc_top(chunk_word_size); 1030 1031 // Initialize the chunk 1032 Metachunk* result = ::new (chunk_limit) Metachunk(chunk_word_size, this); 1033 return result; 1034 } 1035 1036 1037 // Expand the virtual space (commit more of the reserved space) 1038 bool VirtualSpaceNode::expand_by(size_t min_words, size_t preferred_words) { 1039 size_t min_bytes = min_words * BytesPerWord; 1040 size_t preferred_bytes = preferred_words * BytesPerWord; 1041 1042 size_t uncommitted = virtual_space()->reserved_size() - virtual_space()->actual_committed_size(); 1043 1044 if (uncommitted < min_bytes) { 1045 return false; 1046 } 1047 1048 size_t commit = MIN2(preferred_bytes, uncommitted); 1049 bool result = virtual_space()->expand_by(commit, false); 1050 1051 assert(result, "Failed to commit memory"); 1052 1053 return result; 1054 } 1055 1056 Metachunk* VirtualSpaceNode::get_chunk_vs(size_t chunk_word_size) { 1057 assert_lock_strong(SpaceManager::expand_lock()); 1058 Metachunk* result = take_from_committed(chunk_word_size); 1059 if (result != NULL) { 1060 inc_container_count(); 1061 } 1062 return result; 1063 } 1064 1065 bool VirtualSpaceNode::initialize() { 1066 1067 if (!_rs.is_reserved()) { 1068 return false; 1069 } 1070 1071 // These are necessary restriction to make sure that the virtual space always 1072 // grows in steps of Metaspace::commit_alignment(). If both base and size are 1073 // aligned only the middle alignment of the VirtualSpace is used. 1074 assert_is_ptr_aligned(_rs.base(), Metaspace::commit_alignment()); 1075 assert_is_size_aligned(_rs.size(), Metaspace::commit_alignment()); 1076 1077 // ReservedSpaces marked as special will have the entire memory 1078 // pre-committed. Setting a committed size will make sure that 1079 // committed_size and actual_committed_size agrees. 1080 size_t pre_committed_size = _rs.special() ? _rs.size() : 0; 1081 1082 bool result = virtual_space()->initialize_with_granularity(_rs, pre_committed_size, 1083 Metaspace::commit_alignment()); 1084 if (result) { 1085 assert(virtual_space()->committed_size() == virtual_space()->actual_committed_size(), 1086 "Checking that the pre-committed memory was registered by the VirtualSpace"); 1087 1088 set_top((MetaWord*)virtual_space()->low()); 1089 set_reserved(MemRegion((HeapWord*)_rs.base(), 1090 (HeapWord*)(_rs.base() + _rs.size()))); 1091 1092 assert(reserved()->start() == (HeapWord*) _rs.base(), 1093 "Reserved start was not set properly " PTR_FORMAT 1094 " != " PTR_FORMAT, p2i(reserved()->start()), p2i(_rs.base())); 1095 assert(reserved()->word_size() == _rs.size() / BytesPerWord, 1096 "Reserved size was not set properly " SIZE_FORMAT 1097 " != " SIZE_FORMAT, reserved()->word_size(), 1098 _rs.size() / BytesPerWord); 1099 } 1100 1101 return result; 1102 } 1103 1104 void VirtualSpaceNode::print_on(outputStream* st) const { 1105 size_t used = used_words_in_vs(); 1106 size_t capacity = capacity_words_in_vs(); 1107 VirtualSpace* vs = virtual_space(); 1108 st->print_cr(" space @ " PTR_FORMAT " " SIZE_FORMAT "K, " SIZE_FORMAT_W(3) "%% used " 1109 "[" PTR_FORMAT ", " PTR_FORMAT ", " 1110 PTR_FORMAT ", " PTR_FORMAT ")", 1111 p2i(vs), capacity / K, 1112 capacity == 0 ? 0 : used * 100 / capacity, 1113 p2i(bottom()), p2i(top()), p2i(end()), 1114 p2i(vs->high_boundary())); 1115 } 1116 1117 #ifdef ASSERT 1118 void VirtualSpaceNode::mangle() { 1119 size_t word_size = capacity_words_in_vs(); 1120 Copy::fill_to_words((HeapWord*) low(), word_size, 0xf1f1f1f1); 1121 } 1122 #endif // ASSERT 1123 1124 // VirtualSpaceList methods 1125 // Space allocated from the VirtualSpace 1126 1127 VirtualSpaceList::~VirtualSpaceList() { 1128 VirtualSpaceListIterator iter(virtual_space_list()); 1129 while (iter.repeat()) { 1130 VirtualSpaceNode* vsl = iter.get_next(); 1131 delete vsl; 1132 } 1133 } 1134 1135 void VirtualSpaceList::inc_reserved_words(size_t v) { 1136 assert_lock_strong(SpaceManager::expand_lock()); 1137 _reserved_words = _reserved_words + v; 1138 } 1139 void VirtualSpaceList::dec_reserved_words(size_t v) { 1140 assert_lock_strong(SpaceManager::expand_lock()); 1141 _reserved_words = _reserved_words - v; 1142 } 1143 1144 #define assert_committed_below_limit() \ 1145 assert(MetaspaceAux::committed_bytes() <= MaxMetaspaceSize, \ 1146 "Too much committed memory. Committed: " SIZE_FORMAT \ 1147 " limit (MaxMetaspaceSize): " SIZE_FORMAT, \ 1148 MetaspaceAux::committed_bytes(), MaxMetaspaceSize); 1149 1150 void VirtualSpaceList::inc_committed_words(size_t v) { 1151 assert_lock_strong(SpaceManager::expand_lock()); 1152 _committed_words = _committed_words + v; 1153 1154 assert_committed_below_limit(); 1155 } 1156 void VirtualSpaceList::dec_committed_words(size_t v) { 1157 assert_lock_strong(SpaceManager::expand_lock()); 1158 _committed_words = _committed_words - v; 1159 1160 assert_committed_below_limit(); 1161 } 1162 1163 void VirtualSpaceList::inc_virtual_space_count() { 1164 assert_lock_strong(SpaceManager::expand_lock()); 1165 _virtual_space_count++; 1166 } 1167 void VirtualSpaceList::dec_virtual_space_count() { 1168 assert_lock_strong(SpaceManager::expand_lock()); 1169 _virtual_space_count--; 1170 } 1171 1172 void ChunkManager::remove_chunk(Metachunk* chunk) { 1173 size_t word_size = chunk->word_size(); 1174 ChunkIndex index = list_index(word_size); 1175 if (index != HumongousIndex) { 1176 free_chunks(index)->remove_chunk(chunk); 1177 } else { 1178 humongous_dictionary()->remove_chunk(chunk); 1179 } 1180 1181 // Chunk has been removed from the chunks free list, update counters. 1182 account_for_removed_chunk(chunk); 1183 } 1184 1185 // Walk the list of VirtualSpaceNodes and delete 1186 // nodes with a 0 container_count. Remove Metachunks in 1187 // the node from their respective freelists. 1188 void VirtualSpaceList::purge(ChunkManager* chunk_manager) { 1189 assert(SafepointSynchronize::is_at_safepoint(), "must be called at safepoint for contains to work"); 1190 assert_lock_strong(SpaceManager::expand_lock()); 1191 // Don't use a VirtualSpaceListIterator because this 1192 // list is being changed and a straightforward use of an iterator is not safe. 1193 VirtualSpaceNode* purged_vsl = NULL; 1194 VirtualSpaceNode* prev_vsl = virtual_space_list(); 1195 VirtualSpaceNode* next_vsl = prev_vsl; 1196 while (next_vsl != NULL) { 1197 VirtualSpaceNode* vsl = next_vsl; 1198 DEBUG_ONLY(vsl->verify_container_count();) 1199 next_vsl = vsl->next(); 1200 // Don't free the current virtual space since it will likely 1201 // be needed soon. 1202 if (vsl->container_count() == 0 && vsl != current_virtual_space()) { 1203 // Unlink it from the list 1204 if (prev_vsl == vsl) { 1205 // This is the case of the current node being the first node. 1206 assert(vsl == virtual_space_list(), "Expected to be the first node"); 1207 set_virtual_space_list(vsl->next()); 1208 } else { 1209 prev_vsl->set_next(vsl->next()); 1210 } 1211 1212 vsl->purge(chunk_manager); 1213 dec_reserved_words(vsl->reserved_words()); 1214 dec_committed_words(vsl->committed_words()); 1215 dec_virtual_space_count(); 1216 purged_vsl = vsl; 1217 delete vsl; 1218 } else { 1219 prev_vsl = vsl; 1220 } 1221 } 1222 #ifdef ASSERT 1223 if (purged_vsl != NULL) { 1224 // List should be stable enough to use an iterator here. 1225 VirtualSpaceListIterator iter(virtual_space_list()); 1226 while (iter.repeat()) { 1227 VirtualSpaceNode* vsl = iter.get_next(); 1228 assert(vsl != purged_vsl, "Purge of vsl failed"); 1229 } 1230 } 1231 #endif 1232 } 1233 1234 1235 // This function looks at the mmap regions in the metaspace without locking. 1236 // The chunks are added with store ordering and not deleted except for at 1237 // unloading time during a safepoint. 1238 bool VirtualSpaceList::contains(const void* ptr) { 1239 // List should be stable enough to use an iterator here because removing virtual 1240 // space nodes is only allowed at a safepoint. 1241 VirtualSpaceListIterator iter(virtual_space_list()); 1242 while (iter.repeat()) { 1243 VirtualSpaceNode* vsn = iter.get_next(); 1244 if (vsn->contains(ptr)) { 1245 return true; 1246 } 1247 } 1248 return false; 1249 } 1250 1251 void VirtualSpaceList::retire_current_virtual_space() { 1252 assert_lock_strong(SpaceManager::expand_lock()); 1253 1254 VirtualSpaceNode* vsn = current_virtual_space(); 1255 1256 ChunkManager* cm = is_class() ? Metaspace::chunk_manager_class() : 1257 Metaspace::chunk_manager_metadata(); 1258 1259 vsn->retire(cm); 1260 } 1261 1262 void VirtualSpaceNode::retire(ChunkManager* chunk_manager) { 1263 DEBUG_ONLY(verify_container_count();) 1264 for (int i = (int)MediumIndex; i >= (int)ZeroIndex; --i) { 1265 ChunkIndex index = (ChunkIndex)i; 1266 size_t chunk_size = chunk_manager->size_by_index(index); 1267 1268 while (free_words_in_vs() >= chunk_size) { 1269 Metachunk* chunk = get_chunk_vs(chunk_size); 1270 assert(chunk != NULL, "allocation should have been successful"); 1271 1272 chunk_manager->return_single_chunk(index, chunk); 1273 } 1274 DEBUG_ONLY(verify_container_count();) 1275 } 1276 assert(free_words_in_vs() == 0, "should be empty now"); 1277 } 1278 1279 VirtualSpaceList::VirtualSpaceList(size_t word_size) : 1280 _is_class(false), 1281 _virtual_space_list(NULL), 1282 _current_virtual_space(NULL), 1283 _reserved_words(0), 1284 _committed_words(0), 1285 _virtual_space_count(0) { 1286 MutexLockerEx cl(SpaceManager::expand_lock(), 1287 Mutex::_no_safepoint_check_flag); 1288 create_new_virtual_space(word_size); 1289 } 1290 1291 VirtualSpaceList::VirtualSpaceList(ReservedSpace rs) : 1292 _is_class(true), 1293 _virtual_space_list(NULL), 1294 _current_virtual_space(NULL), 1295 _reserved_words(0), 1296 _committed_words(0), 1297 _virtual_space_count(0) { 1298 MutexLockerEx cl(SpaceManager::expand_lock(), 1299 Mutex::_no_safepoint_check_flag); 1300 VirtualSpaceNode* class_entry = new VirtualSpaceNode(rs); 1301 bool succeeded = class_entry->initialize(); 1302 if (succeeded) { 1303 link_vs(class_entry); 1304 } 1305 } 1306 1307 size_t VirtualSpaceList::free_bytes() { 1308 return virtual_space_list()->free_words_in_vs() * BytesPerWord; 1309 } 1310 1311 // Allocate another meta virtual space and add it to the list. 1312 bool VirtualSpaceList::create_new_virtual_space(size_t vs_word_size) { 1313 assert_lock_strong(SpaceManager::expand_lock()); 1314 1315 if (is_class()) { 1316 assert(false, "We currently don't support more than one VirtualSpace for" 1317 " the compressed class space. The initialization of the" 1318 " CCS uses another code path and should not hit this path."); 1319 return false; 1320 } 1321 1322 if (vs_word_size == 0) { 1323 assert(false, "vs_word_size should always be at least _reserve_alignment large."); 1324 return false; 1325 } 1326 1327 // Reserve the space 1328 size_t vs_byte_size = vs_word_size * BytesPerWord; 1329 assert_is_size_aligned(vs_byte_size, Metaspace::reserve_alignment()); 1330 1331 // Allocate the meta virtual space and initialize it. 1332 VirtualSpaceNode* new_entry = new VirtualSpaceNode(vs_byte_size); 1333 if (!new_entry->initialize()) { 1334 delete new_entry; 1335 return false; 1336 } else { 1337 assert(new_entry->reserved_words() == vs_word_size, 1338 "Reserved memory size differs from requested memory size"); 1339 // ensure lock-free iteration sees fully initialized node 1340 OrderAccess::storestore(); 1341 link_vs(new_entry); 1342 return true; 1343 } 1344 } 1345 1346 void VirtualSpaceList::link_vs(VirtualSpaceNode* new_entry) { 1347 if (virtual_space_list() == NULL) { 1348 set_virtual_space_list(new_entry); 1349 } else { 1350 current_virtual_space()->set_next(new_entry); 1351 } 1352 set_current_virtual_space(new_entry); 1353 inc_reserved_words(new_entry->reserved_words()); 1354 inc_committed_words(new_entry->committed_words()); 1355 inc_virtual_space_count(); 1356 #ifdef ASSERT 1357 new_entry->mangle(); 1358 #endif 1359 LogTarget(Trace, gc, metaspace) lt; 1360 if (lt.is_enabled()) { 1361 LogStream ls(lt); 1362 VirtualSpaceNode* vsl = current_virtual_space(); 1363 ResourceMark rm; 1364 vsl->print_on(&ls); 1365 } 1366 } 1367 1368 bool VirtualSpaceList::expand_node_by(VirtualSpaceNode* node, 1369 size_t min_words, 1370 size_t preferred_words) { 1371 size_t before = node->committed_words(); 1372 1373 bool result = node->expand_by(min_words, preferred_words); 1374 1375 size_t after = node->committed_words(); 1376 1377 // after and before can be the same if the memory was pre-committed. 1378 assert(after >= before, "Inconsistency"); 1379 inc_committed_words(after - before); 1380 1381 return result; 1382 } 1383 1384 bool VirtualSpaceList::expand_by(size_t min_words, size_t preferred_words) { 1385 assert_is_size_aligned(min_words, Metaspace::commit_alignment_words()); 1386 assert_is_size_aligned(preferred_words, Metaspace::commit_alignment_words()); 1387 assert(min_words <= preferred_words, "Invalid arguments"); 1388 1389 if (!MetaspaceGC::can_expand(min_words, this->is_class())) { 1390 return false; 1391 } 1392 1393 size_t allowed_expansion_words = MetaspaceGC::allowed_expansion(); 1394 if (allowed_expansion_words < min_words) { 1395 return false; 1396 } 1397 1398 size_t max_expansion_words = MIN2(preferred_words, allowed_expansion_words); 1399 1400 // Commit more memory from the the current virtual space. 1401 bool vs_expanded = expand_node_by(current_virtual_space(), 1402 min_words, 1403 max_expansion_words); 1404 if (vs_expanded) { 1405 return true; 1406 } 1407 retire_current_virtual_space(); 1408 1409 // Get another virtual space. 1410 size_t grow_vs_words = MAX2((size_t)VirtualSpaceSize, preferred_words); 1411 grow_vs_words = align_size_up(grow_vs_words, Metaspace::reserve_alignment_words()); 1412 1413 if (create_new_virtual_space(grow_vs_words)) { 1414 if (current_virtual_space()->is_pre_committed()) { 1415 // The memory was pre-committed, so we are done here. 1416 assert(min_words <= current_virtual_space()->committed_words(), 1417 "The new VirtualSpace was pre-committed, so it" 1418 "should be large enough to fit the alloc request."); 1419 return true; 1420 } 1421 1422 return expand_node_by(current_virtual_space(), 1423 min_words, 1424 max_expansion_words); 1425 } 1426 1427 return false; 1428 } 1429 1430 Metachunk* VirtualSpaceList::get_new_chunk(size_t chunk_word_size, size_t suggested_commit_granularity) { 1431 1432 // Allocate a chunk out of the current virtual space. 1433 Metachunk* next = current_virtual_space()->get_chunk_vs(chunk_word_size); 1434 1435 if (next != NULL) { 1436 return next; 1437 } 1438 1439 // The expand amount is currently only determined by the requested sizes 1440 // and not how much committed memory is left in the current virtual space. 1441 1442 size_t min_word_size = align_size_up(chunk_word_size, Metaspace::commit_alignment_words()); 1443 size_t preferred_word_size = align_size_up(suggested_commit_granularity, Metaspace::commit_alignment_words()); 1444 if (min_word_size >= preferred_word_size) { 1445 // Can happen when humongous chunks are allocated. 1446 preferred_word_size = min_word_size; 1447 } 1448 1449 bool expanded = expand_by(min_word_size, preferred_word_size); 1450 if (expanded) { 1451 next = current_virtual_space()->get_chunk_vs(chunk_word_size); 1452 assert(next != NULL, "The allocation was expected to succeed after the expansion"); 1453 } 1454 1455 return next; 1456 } 1457 1458 void VirtualSpaceList::print_on(outputStream* st) const { 1459 VirtualSpaceListIterator iter(virtual_space_list()); 1460 while (iter.repeat()) { 1461 VirtualSpaceNode* node = iter.get_next(); 1462 node->print_on(st); 1463 } 1464 } 1465 1466 // MetaspaceGC methods 1467 1468 // VM_CollectForMetadataAllocation is the vm operation used to GC. 1469 // Within the VM operation after the GC the attempt to allocate the metadata 1470 // should succeed. If the GC did not free enough space for the metaspace 1471 // allocation, the HWM is increased so that another virtualspace will be 1472 // allocated for the metadata. With perm gen the increase in the perm 1473 // gen had bounds, MinMetaspaceExpansion and MaxMetaspaceExpansion. The 1474 // metaspace policy uses those as the small and large steps for the HWM. 1475 // 1476 // After the GC the compute_new_size() for MetaspaceGC is called to 1477 // resize the capacity of the metaspaces. The current implementation 1478 // is based on the flags MinMetaspaceFreeRatio and MaxMetaspaceFreeRatio used 1479 // to resize the Java heap by some GC's. New flags can be implemented 1480 // if really needed. MinMetaspaceFreeRatio is used to calculate how much 1481 // free space is desirable in the metaspace capacity to decide how much 1482 // to increase the HWM. MaxMetaspaceFreeRatio is used to decide how much 1483 // free space is desirable in the metaspace capacity before decreasing 1484 // the HWM. 1485 1486 // Calculate the amount to increase the high water mark (HWM). 1487 // Increase by a minimum amount (MinMetaspaceExpansion) so that 1488 // another expansion is not requested too soon. If that is not 1489 // enough to satisfy the allocation, increase by MaxMetaspaceExpansion. 1490 // If that is still not enough, expand by the size of the allocation 1491 // plus some. 1492 size_t MetaspaceGC::delta_capacity_until_GC(size_t bytes) { 1493 size_t min_delta = MinMetaspaceExpansion; 1494 size_t max_delta = MaxMetaspaceExpansion; 1495 size_t delta = align_size_up(bytes, Metaspace::commit_alignment()); 1496 1497 if (delta <= min_delta) { 1498 delta = min_delta; 1499 } else if (delta <= max_delta) { 1500 // Don't want to hit the high water mark on the next 1501 // allocation so make the delta greater than just enough 1502 // for this allocation. 1503 delta = max_delta; 1504 } else { 1505 // This allocation is large but the next ones are probably not 1506 // so increase by the minimum. 1507 delta = delta + min_delta; 1508 } 1509 1510 assert_is_size_aligned(delta, Metaspace::commit_alignment()); 1511 1512 return delta; 1513 } 1514 1515 size_t MetaspaceGC::capacity_until_GC() { 1516 size_t value = (size_t)OrderAccess::load_ptr_acquire(&_capacity_until_GC); 1517 assert(value >= MetaspaceSize, "Not initialized properly?"); 1518 return value; 1519 } 1520 1521 bool MetaspaceGC::inc_capacity_until_GC(size_t v, size_t* new_cap_until_GC, size_t* old_cap_until_GC) { 1522 assert_is_size_aligned(v, Metaspace::commit_alignment()); 1523 1524 size_t capacity_until_GC = (size_t) _capacity_until_GC; 1525 size_t new_value = capacity_until_GC + v; 1526 1527 if (new_value < capacity_until_GC) { 1528 // The addition wrapped around, set new_value to aligned max value. 1529 new_value = align_size_down(max_uintx, Metaspace::commit_alignment()); 1530 } 1531 1532 intptr_t expected = (intptr_t) capacity_until_GC; 1533 intptr_t actual = Atomic::cmpxchg_ptr((intptr_t) new_value, &_capacity_until_GC, expected); 1534 1535 if (expected != actual) { 1536 return false; 1537 } 1538 1539 if (new_cap_until_GC != NULL) { 1540 *new_cap_until_GC = new_value; 1541 } 1542 if (old_cap_until_GC != NULL) { 1543 *old_cap_until_GC = capacity_until_GC; 1544 } 1545 return true; 1546 } 1547 1548 size_t MetaspaceGC::dec_capacity_until_GC(size_t v) { 1549 assert_is_size_aligned(v, Metaspace::commit_alignment()); 1550 1551 return (size_t)Atomic::add_ptr(-(intptr_t)v, &_capacity_until_GC); 1552 } 1553 1554 void MetaspaceGC::initialize() { 1555 // Set the high-water mark to MaxMetapaceSize during VM initializaton since 1556 // we can't do a GC during initialization. 1557 _capacity_until_GC = MaxMetaspaceSize; 1558 } 1559 1560 void MetaspaceGC::post_initialize() { 1561 // Reset the high-water mark once the VM initialization is done. 1562 _capacity_until_GC = MAX2(MetaspaceAux::committed_bytes(), MetaspaceSize); 1563 } 1564 1565 bool MetaspaceGC::can_expand(size_t word_size, bool is_class) { 1566 // Check if the compressed class space is full. 1567 if (is_class && Metaspace::using_class_space()) { 1568 size_t class_committed = MetaspaceAux::committed_bytes(Metaspace::ClassType); 1569 if (class_committed + word_size * BytesPerWord > CompressedClassSpaceSize) { 1570 return false; 1571 } 1572 } 1573 1574 // Check if the user has imposed a limit on the metaspace memory. 1575 size_t committed_bytes = MetaspaceAux::committed_bytes(); 1576 if (committed_bytes + word_size * BytesPerWord > MaxMetaspaceSize) { 1577 return false; 1578 } 1579 1580 return true; 1581 } 1582 1583 size_t MetaspaceGC::allowed_expansion() { 1584 size_t committed_bytes = MetaspaceAux::committed_bytes(); 1585 size_t capacity_until_gc = capacity_until_GC(); 1586 1587 assert(capacity_until_gc >= committed_bytes, 1588 "capacity_until_gc: " SIZE_FORMAT " < committed_bytes: " SIZE_FORMAT, 1589 capacity_until_gc, committed_bytes); 1590 1591 size_t left_until_max = MaxMetaspaceSize - committed_bytes; 1592 size_t left_until_GC = capacity_until_gc - committed_bytes; 1593 size_t left_to_commit = MIN2(left_until_GC, left_until_max); 1594 1595 return left_to_commit / BytesPerWord; 1596 } 1597 1598 void MetaspaceGC::compute_new_size() { 1599 assert(_shrink_factor <= 100, "invalid shrink factor"); 1600 uint current_shrink_factor = _shrink_factor; 1601 _shrink_factor = 0; 1602 1603 // Using committed_bytes() for used_after_gc is an overestimation, since the 1604 // chunk free lists are included in committed_bytes() and the memory in an 1605 // un-fragmented chunk free list is available for future allocations. 1606 // However, if the chunk free lists becomes fragmented, then the memory may 1607 // not be available for future allocations and the memory is therefore "in use". 1608 // Including the chunk free lists in the definition of "in use" is therefore 1609 // necessary. Not including the chunk free lists can cause capacity_until_GC to 1610 // shrink below committed_bytes() and this has caused serious bugs in the past. 1611 const size_t used_after_gc = MetaspaceAux::committed_bytes(); 1612 const size_t capacity_until_GC = MetaspaceGC::capacity_until_GC(); 1613 1614 const double minimum_free_percentage = MinMetaspaceFreeRatio / 100.0; 1615 const double maximum_used_percentage = 1.0 - minimum_free_percentage; 1616 1617 const double min_tmp = used_after_gc / maximum_used_percentage; 1618 size_t minimum_desired_capacity = 1619 (size_t)MIN2(min_tmp, double(max_uintx)); 1620 // Don't shrink less than the initial generation size 1621 minimum_desired_capacity = MAX2(minimum_desired_capacity, 1622 MetaspaceSize); 1623 1624 log_trace(gc, metaspace)("MetaspaceGC::compute_new_size: "); 1625 log_trace(gc, metaspace)(" minimum_free_percentage: %6.2f maximum_used_percentage: %6.2f", 1626 minimum_free_percentage, maximum_used_percentage); 1627 log_trace(gc, metaspace)(" used_after_gc : %6.1fKB", used_after_gc / (double) K); 1628 1629 1630 size_t shrink_bytes = 0; 1631 if (capacity_until_GC < minimum_desired_capacity) { 1632 // If we have less capacity below the metaspace HWM, then 1633 // increment the HWM. 1634 size_t expand_bytes = minimum_desired_capacity - capacity_until_GC; 1635 expand_bytes = align_size_up(expand_bytes, Metaspace::commit_alignment()); 1636 // Don't expand unless it's significant 1637 if (expand_bytes >= MinMetaspaceExpansion) { 1638 size_t new_capacity_until_GC = 0; 1639 bool succeeded = MetaspaceGC::inc_capacity_until_GC(expand_bytes, &new_capacity_until_GC); 1640 assert(succeeded, "Should always succesfully increment HWM when at safepoint"); 1641 1642 Metaspace::tracer()->report_gc_threshold(capacity_until_GC, 1643 new_capacity_until_GC, 1644 MetaspaceGCThresholdUpdater::ComputeNewSize); 1645 log_trace(gc, metaspace)(" expanding: minimum_desired_capacity: %6.1fKB expand_bytes: %6.1fKB MinMetaspaceExpansion: %6.1fKB new metaspace HWM: %6.1fKB", 1646 minimum_desired_capacity / (double) K, 1647 expand_bytes / (double) K, 1648 MinMetaspaceExpansion / (double) K, 1649 new_capacity_until_GC / (double) K); 1650 } 1651 return; 1652 } 1653 1654 // No expansion, now see if we want to shrink 1655 // We would never want to shrink more than this 1656 assert(capacity_until_GC >= minimum_desired_capacity, 1657 SIZE_FORMAT " >= " SIZE_FORMAT, 1658 capacity_until_GC, minimum_desired_capacity); 1659 size_t max_shrink_bytes = capacity_until_GC - minimum_desired_capacity; 1660 1661 // Should shrinking be considered? 1662 if (MaxMetaspaceFreeRatio < 100) { 1663 const double maximum_free_percentage = MaxMetaspaceFreeRatio / 100.0; 1664 const double minimum_used_percentage = 1.0 - maximum_free_percentage; 1665 const double max_tmp = used_after_gc / minimum_used_percentage; 1666 size_t maximum_desired_capacity = (size_t)MIN2(max_tmp, double(max_uintx)); 1667 maximum_desired_capacity = MAX2(maximum_desired_capacity, 1668 MetaspaceSize); 1669 log_trace(gc, metaspace)(" maximum_free_percentage: %6.2f minimum_used_percentage: %6.2f", 1670 maximum_free_percentage, minimum_used_percentage); 1671 log_trace(gc, metaspace)(" minimum_desired_capacity: %6.1fKB maximum_desired_capacity: %6.1fKB", 1672 minimum_desired_capacity / (double) K, maximum_desired_capacity / (double) K); 1673 1674 assert(minimum_desired_capacity <= maximum_desired_capacity, 1675 "sanity check"); 1676 1677 if (capacity_until_GC > maximum_desired_capacity) { 1678 // Capacity too large, compute shrinking size 1679 shrink_bytes = capacity_until_GC - maximum_desired_capacity; 1680 // We don't want shrink all the way back to initSize if people call 1681 // System.gc(), because some programs do that between "phases" and then 1682 // we'd just have to grow the heap up again for the next phase. So we 1683 // damp the shrinking: 0% on the first call, 10% on the second call, 40% 1684 // on the third call, and 100% by the fourth call. But if we recompute 1685 // size without shrinking, it goes back to 0%. 1686 shrink_bytes = shrink_bytes / 100 * current_shrink_factor; 1687 1688 shrink_bytes = align_size_down(shrink_bytes, Metaspace::commit_alignment()); 1689 1690 assert(shrink_bytes <= max_shrink_bytes, 1691 "invalid shrink size " SIZE_FORMAT " not <= " SIZE_FORMAT, 1692 shrink_bytes, max_shrink_bytes); 1693 if (current_shrink_factor == 0) { 1694 _shrink_factor = 10; 1695 } else { 1696 _shrink_factor = MIN2(current_shrink_factor * 4, (uint) 100); 1697 } 1698 log_trace(gc, metaspace)(" shrinking: initThreshold: %.1fK maximum_desired_capacity: %.1fK", 1699 MetaspaceSize / (double) K, maximum_desired_capacity / (double) K); 1700 log_trace(gc, metaspace)(" shrink_bytes: %.1fK current_shrink_factor: %d new shrink factor: %d MinMetaspaceExpansion: %.1fK", 1701 shrink_bytes / (double) K, current_shrink_factor, _shrink_factor, MinMetaspaceExpansion / (double) K); 1702 } 1703 } 1704 1705 // Don't shrink unless it's significant 1706 if (shrink_bytes >= MinMetaspaceExpansion && 1707 ((capacity_until_GC - shrink_bytes) >= MetaspaceSize)) { 1708 size_t new_capacity_until_GC = MetaspaceGC::dec_capacity_until_GC(shrink_bytes); 1709 Metaspace::tracer()->report_gc_threshold(capacity_until_GC, 1710 new_capacity_until_GC, 1711 MetaspaceGCThresholdUpdater::ComputeNewSize); 1712 } 1713 } 1714 1715 // Metadebug methods 1716 1717 void Metadebug::init_allocation_fail_alot_count() { 1718 if (MetadataAllocationFailALot) { 1719 _allocation_fail_alot_count = 1720 1+(long)((double)MetadataAllocationFailALotInterval*os::random()/(max_jint+1.0)); 1721 } 1722 } 1723 1724 #ifdef ASSERT 1725 bool Metadebug::test_metadata_failure() { 1726 if (MetadataAllocationFailALot && 1727 Threads::is_vm_complete()) { 1728 if (_allocation_fail_alot_count > 0) { 1729 _allocation_fail_alot_count--; 1730 } else { 1731 log_trace(gc, metaspace, freelist)("Metadata allocation failing for MetadataAllocationFailALot"); 1732 init_allocation_fail_alot_count(); 1733 return true; 1734 } 1735 } 1736 return false; 1737 } 1738 #endif 1739 1740 // ChunkManager methods 1741 1742 size_t ChunkManager::free_chunks_total_words() { 1743 return _free_chunks_total; 1744 } 1745 1746 size_t ChunkManager::free_chunks_total_bytes() { 1747 return free_chunks_total_words() * BytesPerWord; 1748 } 1749 1750 // Update internal accounting after a chunk was added 1751 void ChunkManager::account_for_added_chunk(const Metachunk* c) { 1752 assert_lock_strong(SpaceManager::expand_lock()); 1753 _free_chunks_count ++; 1754 _free_chunks_total += c->word_size(); 1755 } 1756 1757 // Update internal accounting after a chunk was removed 1758 void ChunkManager::account_for_removed_chunk(const Metachunk* c) { 1759 assert_lock_strong(SpaceManager::expand_lock()); 1760 assert(_free_chunks_count >= 1, 1761 "ChunkManager::_free_chunks_count: about to go negative (" SIZE_FORMAT ").", _free_chunks_count); 1762 assert(_free_chunks_total >= c->word_size(), 1763 "ChunkManager::_free_chunks_total: about to go negative" 1764 "(now: " SIZE_FORMAT ", decrement value: " SIZE_FORMAT ").", _free_chunks_total, c->word_size()); 1765 _free_chunks_count --; 1766 _free_chunks_total -= c->word_size(); 1767 } 1768 1769 size_t ChunkManager::free_chunks_count() { 1770 #ifdef ASSERT 1771 if (!UseConcMarkSweepGC && !SpaceManager::expand_lock()->is_locked()) { 1772 MutexLockerEx cl(SpaceManager::expand_lock(), 1773 Mutex::_no_safepoint_check_flag); 1774 // This lock is only needed in debug because the verification 1775 // of the _free_chunks_totals walks the list of free chunks 1776 slow_locked_verify_free_chunks_count(); 1777 } 1778 #endif 1779 return _free_chunks_count; 1780 } 1781 1782 ChunkIndex ChunkManager::list_index(size_t size) { 1783 if (size_by_index(SpecializedIndex) == size) { 1784 return SpecializedIndex; 1785 } 1786 if (size_by_index(SmallIndex) == size) { 1787 return SmallIndex; 1788 } 1789 const size_t med_size = size_by_index(MediumIndex); 1790 if (med_size == size) { 1791 return MediumIndex; 1792 } 1793 1794 assert(size > med_size, "Not a humongous chunk"); 1795 return HumongousIndex; 1796 } 1797 1798 size_t ChunkManager::size_by_index(ChunkIndex index) { 1799 index_bounds_check(index); 1800 assert(index != HumongousIndex, "Do not call for humongous chunks."); 1801 return free_chunks(index)->size(); 1802 } 1803 1804 void ChunkManager::locked_verify_free_chunks_total() { 1805 assert_lock_strong(SpaceManager::expand_lock()); 1806 assert(sum_free_chunks() == _free_chunks_total, 1807 "_free_chunks_total " SIZE_FORMAT " is not the" 1808 " same as sum " SIZE_FORMAT, _free_chunks_total, 1809 sum_free_chunks()); 1810 } 1811 1812 void ChunkManager::verify_free_chunks_total() { 1813 MutexLockerEx cl(SpaceManager::expand_lock(), 1814 Mutex::_no_safepoint_check_flag); 1815 locked_verify_free_chunks_total(); 1816 } 1817 1818 void ChunkManager::locked_verify_free_chunks_count() { 1819 assert_lock_strong(SpaceManager::expand_lock()); 1820 assert(sum_free_chunks_count() == _free_chunks_count, 1821 "_free_chunks_count " SIZE_FORMAT " is not the" 1822 " same as sum " SIZE_FORMAT, _free_chunks_count, 1823 sum_free_chunks_count()); 1824 } 1825 1826 void ChunkManager::verify_free_chunks_count() { 1827 #ifdef ASSERT 1828 MutexLockerEx cl(SpaceManager::expand_lock(), 1829 Mutex::_no_safepoint_check_flag); 1830 locked_verify_free_chunks_count(); 1831 #endif 1832 } 1833 1834 void ChunkManager::verify() { 1835 MutexLockerEx cl(SpaceManager::expand_lock(), 1836 Mutex::_no_safepoint_check_flag); 1837 locked_verify(); 1838 } 1839 1840 void ChunkManager::locked_verify() { 1841 locked_verify_free_chunks_count(); 1842 locked_verify_free_chunks_total(); 1843 } 1844 1845 void ChunkManager::locked_print_free_chunks(outputStream* st) { 1846 assert_lock_strong(SpaceManager::expand_lock()); 1847 st->print_cr("Free chunk total " SIZE_FORMAT " count " SIZE_FORMAT, 1848 _free_chunks_total, _free_chunks_count); 1849 } 1850 1851 void ChunkManager::locked_print_sum_free_chunks(outputStream* st) { 1852 assert_lock_strong(SpaceManager::expand_lock()); 1853 st->print_cr("Sum free chunk total " SIZE_FORMAT " count " SIZE_FORMAT, 1854 sum_free_chunks(), sum_free_chunks_count()); 1855 } 1856 1857 ChunkList* ChunkManager::free_chunks(ChunkIndex index) { 1858 assert(index == SpecializedIndex || index == SmallIndex || index == MediumIndex, 1859 "Bad index: %d", (int)index); 1860 1861 return &_free_chunks[index]; 1862 } 1863 1864 // These methods that sum the free chunk lists are used in printing 1865 // methods that are used in product builds. 1866 size_t ChunkManager::sum_free_chunks() { 1867 assert_lock_strong(SpaceManager::expand_lock()); 1868 size_t result = 0; 1869 for (ChunkIndex i = ZeroIndex; i < NumberOfFreeLists; i = next_chunk_index(i)) { 1870 ChunkList* list = free_chunks(i); 1871 1872 if (list == NULL) { 1873 continue; 1874 } 1875 1876 result = result + list->count() * list->size(); 1877 } 1878 result = result + humongous_dictionary()->total_size(); 1879 return result; 1880 } 1881 1882 size_t ChunkManager::sum_free_chunks_count() { 1883 assert_lock_strong(SpaceManager::expand_lock()); 1884 size_t count = 0; 1885 for (ChunkIndex i = ZeroIndex; i < NumberOfFreeLists; i = next_chunk_index(i)) { 1886 ChunkList* list = free_chunks(i); 1887 if (list == NULL) { 1888 continue; 1889 } 1890 count = count + list->count(); 1891 } 1892 count = count + humongous_dictionary()->total_free_blocks(); 1893 return count; 1894 } 1895 1896 ChunkList* ChunkManager::find_free_chunks_list(size_t word_size) { 1897 ChunkIndex index = list_index(word_size); 1898 assert(index < HumongousIndex, "No humongous list"); 1899 return free_chunks(index); 1900 } 1901 1902 Metachunk* ChunkManager::free_chunks_get(size_t word_size) { 1903 assert_lock_strong(SpaceManager::expand_lock()); 1904 1905 slow_locked_verify(); 1906 1907 Metachunk* chunk = NULL; 1908 if (list_index(word_size) != HumongousIndex) { 1909 ChunkList* free_list = find_free_chunks_list(word_size); 1910 assert(free_list != NULL, "Sanity check"); 1911 1912 chunk = free_list->head(); 1913 1914 if (chunk == NULL) { 1915 return NULL; 1916 } 1917 1918 // Remove the chunk as the head of the list. 1919 free_list->remove_chunk(chunk); 1920 1921 log_trace(gc, metaspace, freelist)("ChunkManager::free_chunks_get: free_list " PTR_FORMAT " head " PTR_FORMAT " size " SIZE_FORMAT, 1922 p2i(free_list), p2i(chunk), chunk->word_size()); 1923 } else { 1924 chunk = humongous_dictionary()->get_chunk( 1925 word_size, 1926 FreeBlockDictionary<Metachunk>::atLeast); 1927 1928 if (chunk == NULL) { 1929 return NULL; 1930 } 1931 1932 log_debug(gc, metaspace, alloc)("Free list allocate humongous chunk size " SIZE_FORMAT " for requested size " SIZE_FORMAT " waste " SIZE_FORMAT, 1933 chunk->word_size(), word_size, chunk->word_size() - word_size); 1934 } 1935 1936 // Chunk has been removed from the chunk manager; update counters. 1937 account_for_removed_chunk(chunk); 1938 1939 // Remove it from the links to this freelist 1940 chunk->set_next(NULL); 1941 chunk->set_prev(NULL); 1942 #ifdef ASSERT 1943 // Chunk is no longer on any freelist. Setting to false make container_count_slow() 1944 // work. 1945 chunk->set_is_tagged_free(false); 1946 #endif 1947 chunk->container()->inc_container_count(); 1948 1949 slow_locked_verify(); 1950 return chunk; 1951 } 1952 1953 Metachunk* ChunkManager::chunk_freelist_allocate(size_t word_size) { 1954 assert_lock_strong(SpaceManager::expand_lock()); 1955 slow_locked_verify(); 1956 1957 // Take from the beginning of the list 1958 Metachunk* chunk = free_chunks_get(word_size); 1959 if (chunk == NULL) { 1960 return NULL; 1961 } 1962 1963 assert((word_size <= chunk->word_size()) || 1964 (list_index(chunk->word_size()) == HumongousIndex), 1965 "Non-humongous variable sized chunk"); 1966 LogTarget(Debug, gc, metaspace, freelist) lt; 1967 if (lt.is_enabled()) { 1968 size_t list_count; 1969 if (list_index(word_size) < HumongousIndex) { 1970 ChunkList* list = find_free_chunks_list(word_size); 1971 list_count = list->count(); 1972 } else { 1973 list_count = humongous_dictionary()->total_count(); 1974 } 1975 LogStream ls(lt); 1976 ls.print("ChunkManager::chunk_freelist_allocate: " PTR_FORMAT " chunk " PTR_FORMAT " size " SIZE_FORMAT " count " SIZE_FORMAT " ", 1977 p2i(this), p2i(chunk), chunk->word_size(), list_count); 1978 ResourceMark rm; 1979 locked_print_free_chunks(&ls); 1980 } 1981 1982 return chunk; 1983 } 1984 1985 void ChunkManager::return_single_chunk(ChunkIndex index, Metachunk* chunk) { 1986 assert_lock_strong(SpaceManager::expand_lock()); 1987 assert(chunk != NULL, "Expected chunk."); 1988 assert(chunk->container() != NULL, "Container should have been set."); 1989 assert(chunk->is_tagged_free() == false, "Chunk should be in use."); 1990 index_bounds_check(index); 1991 1992 // Note: mangle *before* returning the chunk to the freelist or dictionary. It does not 1993 // matter for the freelist (non-humongous chunks), but the humongous chunk dictionary 1994 // keeps tree node pointers in the chunk payload area which mangle will overwrite. 1995 NOT_PRODUCT(chunk->mangle(badMetaWordVal);) 1996 1997 if (index != HumongousIndex) { 1998 // Return non-humongous chunk to freelist. 1999 ChunkList* list = free_chunks(index); 2000 assert(list->size() == chunk->word_size(), "Wrong chunk type."); 2001 list->return_chunk_at_head(chunk); 2002 log_trace(gc, metaspace, freelist)("returned one %s chunk at " PTR_FORMAT " to freelist.", 2003 chunk_size_name(index), p2i(chunk)); 2004 } else { 2005 // Return humongous chunk to dictionary. 2006 assert(chunk->word_size() > free_chunks(MediumIndex)->size(), "Wrong chunk type."); 2007 assert(chunk->word_size() % free_chunks(SpecializedIndex)->size() == 0, 2008 "Humongous chunk has wrong alignment."); 2009 _humongous_dictionary.return_chunk(chunk); 2010 log_trace(gc, metaspace, freelist)("returned one %s chunk at " PTR_FORMAT " (word size " SIZE_FORMAT ") to freelist.", 2011 chunk_size_name(index), p2i(chunk), chunk->word_size()); 2012 } 2013 chunk->container()->dec_container_count(); 2014 DEBUG_ONLY(chunk->set_is_tagged_free(true);) 2015 2016 // Chunk has been added; update counters. 2017 account_for_added_chunk(chunk); 2018 2019 } 2020 2021 void ChunkManager::return_chunk_list(ChunkIndex index, Metachunk* chunks) { 2022 index_bounds_check(index); 2023 if (chunks == NULL) { 2024 return; 2025 } 2026 LogTarget(Trace, gc, metaspace, freelist) log; 2027 if (log.is_enabled()) { // tracing 2028 log.print("returning list of %s chunks...", chunk_size_name(index)); 2029 } 2030 unsigned num_chunks_returned = 0; 2031 size_t size_chunks_returned = 0; 2032 Metachunk* cur = chunks; 2033 while (cur != NULL) { 2034 // Capture the next link before it is changed 2035 // by the call to return_chunk_at_head(); 2036 Metachunk* next = cur->next(); 2037 if (log.is_enabled()) { // tracing 2038 num_chunks_returned ++; 2039 size_chunks_returned += cur->word_size(); 2040 } 2041 return_single_chunk(index, cur); 2042 cur = next; 2043 } 2044 if (log.is_enabled()) { // tracing 2045 log.print("returned %u %s chunks to freelist, total word size " SIZE_FORMAT ".", 2046 num_chunks_returned, chunk_size_name(index), size_chunks_returned); 2047 if (index != HumongousIndex) { 2048 log.print("updated freelist count: " SIZE_FORMAT ".", free_chunks(index)->size()); 2049 } else { 2050 log.print("updated dictionary count " SIZE_FORMAT ".", _humongous_dictionary.total_count()); 2051 } 2052 } 2053 } 2054 2055 void ChunkManager::print_on(outputStream* out) const { 2056 const_cast<ChunkManager *>(this)->humongous_dictionary()->report_statistics(out); 2057 } 2058 2059 // SpaceManager methods 2060 2061 size_t SpaceManager::adjust_initial_chunk_size(size_t requested, bool is_class_space) { 2062 size_t chunk_sizes[] = { 2063 specialized_chunk_size(is_class_space), 2064 small_chunk_size(is_class_space), 2065 medium_chunk_size(is_class_space) 2066 }; 2067 2068 // Adjust up to one of the fixed chunk sizes ... 2069 for (size_t i = 0; i < ARRAY_SIZE(chunk_sizes); i++) { 2070 if (requested <= chunk_sizes[i]) { 2071 return chunk_sizes[i]; 2072 } 2073 } 2074 2075 // ... or return the size as a humongous chunk. 2076 return requested; 2077 } 2078 2079 size_t SpaceManager::adjust_initial_chunk_size(size_t requested) const { 2080 return adjust_initial_chunk_size(requested, is_class()); 2081 } 2082 2083 size_t SpaceManager::get_initial_chunk_size(Metaspace::MetaspaceType type) const { 2084 size_t requested; 2085 2086 if (is_class()) { 2087 switch (type) { 2088 case Metaspace::BootMetaspaceType: requested = Metaspace::first_class_chunk_word_size(); break; 2089 case Metaspace::ROMetaspaceType: requested = ClassSpecializedChunk; break; 2090 case Metaspace::ReadWriteMetaspaceType: requested = ClassSpecializedChunk; break; 2091 case Metaspace::AnonymousMetaspaceType: requested = ClassSpecializedChunk; break; 2092 case Metaspace::ReflectionMetaspaceType: requested = ClassSpecializedChunk; break; 2093 default: requested = ClassSmallChunk; break; 2094 } 2095 } else { 2096 switch (type) { 2097 case Metaspace::BootMetaspaceType: requested = Metaspace::first_chunk_word_size(); break; 2098 case Metaspace::ROMetaspaceType: requested = SharedReadOnlySize / wordSize; break; 2099 case Metaspace::ReadWriteMetaspaceType: requested = SharedReadWriteSize / wordSize; break; 2100 case Metaspace::AnonymousMetaspaceType: requested = SpecializedChunk; break; 2101 case Metaspace::ReflectionMetaspaceType: requested = SpecializedChunk; break; 2102 default: requested = SmallChunk; break; 2103 } 2104 } 2105 2106 // Adjust to one of the fixed chunk sizes (unless humongous) 2107 const size_t adjusted = adjust_initial_chunk_size(requested); 2108 2109 assert(adjusted != 0, "Incorrect initial chunk size. Requested: " 2110 SIZE_FORMAT " adjusted: " SIZE_FORMAT, requested, adjusted); 2111 2112 return adjusted; 2113 } 2114 2115 size_t SpaceManager::sum_free_in_chunks_in_use() const { 2116 MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag); 2117 size_t free = 0; 2118 for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) { 2119 Metachunk* chunk = chunks_in_use(i); 2120 while (chunk != NULL) { 2121 free += chunk->free_word_size(); 2122 chunk = chunk->next(); 2123 } 2124 } 2125 return free; 2126 } 2127 2128 size_t SpaceManager::sum_waste_in_chunks_in_use() const { 2129 MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag); 2130 size_t result = 0; 2131 for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) { 2132 result += sum_waste_in_chunks_in_use(i); 2133 } 2134 2135 return result; 2136 } 2137 2138 size_t SpaceManager::sum_waste_in_chunks_in_use(ChunkIndex index) const { 2139 size_t result = 0; 2140 Metachunk* chunk = chunks_in_use(index); 2141 // Count the free space in all the chunk but not the 2142 // current chunk from which allocations are still being done. 2143 while (chunk != NULL) { 2144 if (chunk != current_chunk()) { 2145 result += chunk->free_word_size(); 2146 } 2147 chunk = chunk->next(); 2148 } 2149 return result; 2150 } 2151 2152 size_t SpaceManager::sum_capacity_in_chunks_in_use() const { 2153 // For CMS use "allocated_chunks_words()" which does not need the 2154 // Metaspace lock. For the other collectors sum over the 2155 // lists. Use both methods as a check that "allocated_chunks_words()" 2156 // is correct. That is, sum_capacity_in_chunks() is too expensive 2157 // to use in the product and allocated_chunks_words() should be used 2158 // but allow for checking that allocated_chunks_words() returns the same 2159 // value as sum_capacity_in_chunks_in_use() which is the definitive 2160 // answer. 2161 if (UseConcMarkSweepGC) { 2162 return allocated_chunks_words(); 2163 } else { 2164 MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag); 2165 size_t sum = 0; 2166 for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) { 2167 Metachunk* chunk = chunks_in_use(i); 2168 while (chunk != NULL) { 2169 sum += chunk->word_size(); 2170 chunk = chunk->next(); 2171 } 2172 } 2173 return sum; 2174 } 2175 } 2176 2177 size_t SpaceManager::sum_count_in_chunks_in_use() { 2178 size_t count = 0; 2179 for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) { 2180 count = count + sum_count_in_chunks_in_use(i); 2181 } 2182 2183 return count; 2184 } 2185 2186 size_t SpaceManager::sum_count_in_chunks_in_use(ChunkIndex i) { 2187 size_t count = 0; 2188 Metachunk* chunk = chunks_in_use(i); 2189 while (chunk != NULL) { 2190 count++; 2191 chunk = chunk->next(); 2192 } 2193 return count; 2194 } 2195 2196 2197 size_t SpaceManager::sum_used_in_chunks_in_use() const { 2198 MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag); 2199 size_t used = 0; 2200 for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) { 2201 Metachunk* chunk = chunks_in_use(i); 2202 while (chunk != NULL) { 2203 used += chunk->used_word_size(); 2204 chunk = chunk->next(); 2205 } 2206 } 2207 return used; 2208 } 2209 2210 void SpaceManager::locked_print_chunks_in_use_on(outputStream* st) const { 2211 2212 for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) { 2213 Metachunk* chunk = chunks_in_use(i); 2214 st->print("SpaceManager: %s " PTR_FORMAT, 2215 chunk_size_name(i), p2i(chunk)); 2216 if (chunk != NULL) { 2217 st->print_cr(" free " SIZE_FORMAT, 2218 chunk->free_word_size()); 2219 } else { 2220 st->cr(); 2221 } 2222 } 2223 2224 chunk_manager()->locked_print_free_chunks(st); 2225 chunk_manager()->locked_print_sum_free_chunks(st); 2226 } 2227 2228 size_t SpaceManager::calc_chunk_size(size_t word_size) { 2229 2230 // Decide between a small chunk and a medium chunk. Up to 2231 // _small_chunk_limit small chunks can be allocated. 2232 // After that a medium chunk is preferred. 2233 size_t chunk_word_size; 2234 if (chunks_in_use(MediumIndex) == NULL && 2235 sum_count_in_chunks_in_use(SmallIndex) < _small_chunk_limit) { 2236 chunk_word_size = (size_t) small_chunk_size(); 2237 if (word_size + Metachunk::overhead() > small_chunk_size()) { 2238 chunk_word_size = medium_chunk_size(); 2239 } 2240 } else { 2241 chunk_word_size = medium_chunk_size(); 2242 } 2243 2244 // Might still need a humongous chunk. Enforce 2245 // humongous allocations sizes to be aligned up to 2246 // the smallest chunk size. 2247 size_t if_humongous_sized_chunk = 2248 align_size_up(word_size + Metachunk::overhead(), 2249 smallest_chunk_size()); 2250 chunk_word_size = 2251 MAX2((size_t) chunk_word_size, if_humongous_sized_chunk); 2252 2253 assert(!SpaceManager::is_humongous(word_size) || 2254 chunk_word_size == if_humongous_sized_chunk, 2255 "Size calculation is wrong, word_size " SIZE_FORMAT 2256 " chunk_word_size " SIZE_FORMAT, 2257 word_size, chunk_word_size); 2258 Log(gc, metaspace, alloc) log; 2259 if (log.is_debug() && SpaceManager::is_humongous(word_size)) { 2260 log.debug("Metadata humongous allocation:"); 2261 log.debug(" word_size " PTR_FORMAT, word_size); 2262 log.debug(" chunk_word_size " PTR_FORMAT, chunk_word_size); 2263 log.debug(" chunk overhead " PTR_FORMAT, Metachunk::overhead()); 2264 } 2265 return chunk_word_size; 2266 } 2267 2268 void SpaceManager::track_metaspace_memory_usage() { 2269 if (is_init_completed()) { 2270 if (is_class()) { 2271 MemoryService::track_compressed_class_memory_usage(); 2272 } 2273 MemoryService::track_metaspace_memory_usage(); 2274 } 2275 } 2276 2277 MetaWord* SpaceManager::grow_and_allocate(size_t word_size) { 2278 assert(vs_list()->current_virtual_space() != NULL, 2279 "Should have been set"); 2280 assert(current_chunk() == NULL || 2281 current_chunk()->allocate(word_size) == NULL, 2282 "Don't need to expand"); 2283 MutexLockerEx cl(SpaceManager::expand_lock(), Mutex::_no_safepoint_check_flag); 2284 2285 if (log_is_enabled(Trace, gc, metaspace, freelist)) { 2286 size_t words_left = 0; 2287 size_t words_used = 0; 2288 if (current_chunk() != NULL) { 2289 words_left = current_chunk()->free_word_size(); 2290 words_used = current_chunk()->used_word_size(); 2291 } 2292 log_trace(gc, metaspace, freelist)("SpaceManager::grow_and_allocate for " SIZE_FORMAT " words " SIZE_FORMAT " words used " SIZE_FORMAT " words left", 2293 word_size, words_used, words_left); 2294 } 2295 2296 // Get another chunk 2297 size_t chunk_word_size = calc_chunk_size(word_size); 2298 Metachunk* next = get_new_chunk(chunk_word_size); 2299 2300 MetaWord* mem = NULL; 2301 2302 // If a chunk was available, add it to the in-use chunk list 2303 // and do an allocation from it. 2304 if (next != NULL) { 2305 // Add to this manager's list of chunks in use. 2306 add_chunk(next, false); 2307 mem = next->allocate(word_size); 2308 } 2309 2310 // Track metaspace memory usage statistic. 2311 track_metaspace_memory_usage(); 2312 2313 return mem; 2314 } 2315 2316 void SpaceManager::print_on(outputStream* st) const { 2317 2318 for (ChunkIndex i = ZeroIndex; 2319 i < NumberOfInUseLists ; 2320 i = next_chunk_index(i) ) { 2321 st->print_cr(" chunks_in_use " PTR_FORMAT " chunk size " SIZE_FORMAT, 2322 p2i(chunks_in_use(i)), 2323 chunks_in_use(i) == NULL ? 0 : chunks_in_use(i)->word_size()); 2324 } 2325 st->print_cr(" waste: Small " SIZE_FORMAT " Medium " SIZE_FORMAT 2326 " Humongous " SIZE_FORMAT, 2327 sum_waste_in_chunks_in_use(SmallIndex), 2328 sum_waste_in_chunks_in_use(MediumIndex), 2329 sum_waste_in_chunks_in_use(HumongousIndex)); 2330 // block free lists 2331 if (block_freelists() != NULL) { 2332 st->print_cr("total in block free lists " SIZE_FORMAT, 2333 block_freelists()->total_size()); 2334 } 2335 } 2336 2337 SpaceManager::SpaceManager(Metaspace::MetadataType mdtype, 2338 Mutex* lock) : 2339 _mdtype(mdtype), 2340 _allocated_blocks_words(0), 2341 _allocated_chunks_words(0), 2342 _allocated_chunks_count(0), 2343 _block_freelists(NULL), 2344 _lock(lock) 2345 { 2346 initialize(); 2347 } 2348 2349 void SpaceManager::inc_size_metrics(size_t words) { 2350 assert_lock_strong(SpaceManager::expand_lock()); 2351 // Total of allocated Metachunks and allocated Metachunks count 2352 // for each SpaceManager 2353 _allocated_chunks_words = _allocated_chunks_words + words; 2354 _allocated_chunks_count++; 2355 // Global total of capacity in allocated Metachunks 2356 MetaspaceAux::inc_capacity(mdtype(), words); 2357 // Global total of allocated Metablocks. 2358 // used_words_slow() includes the overhead in each 2359 // Metachunk so include it in the used when the 2360 // Metachunk is first added (so only added once per 2361 // Metachunk). 2362 MetaspaceAux::inc_used(mdtype(), Metachunk::overhead()); 2363 } 2364 2365 void SpaceManager::inc_used_metrics(size_t words) { 2366 // Add to the per SpaceManager total 2367 Atomic::add_ptr(words, &_allocated_blocks_words); 2368 // Add to the global total 2369 MetaspaceAux::inc_used(mdtype(), words); 2370 } 2371 2372 void SpaceManager::dec_total_from_size_metrics() { 2373 MetaspaceAux::dec_capacity(mdtype(), allocated_chunks_words()); 2374 MetaspaceAux::dec_used(mdtype(), allocated_blocks_words()); 2375 // Also deduct the overhead per Metachunk 2376 MetaspaceAux::dec_used(mdtype(), allocated_chunks_count() * Metachunk::overhead()); 2377 } 2378 2379 void SpaceManager::initialize() { 2380 Metadebug::init_allocation_fail_alot_count(); 2381 for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) { 2382 _chunks_in_use[i] = NULL; 2383 } 2384 _current_chunk = NULL; 2385 log_trace(gc, metaspace, freelist)("SpaceManager(): " PTR_FORMAT, p2i(this)); 2386 } 2387 2388 SpaceManager::~SpaceManager() { 2389 // This call this->_lock which can't be done while holding expand_lock() 2390 assert(sum_capacity_in_chunks_in_use() == allocated_chunks_words(), 2391 "sum_capacity_in_chunks_in_use() " SIZE_FORMAT 2392 " allocated_chunks_words() " SIZE_FORMAT, 2393 sum_capacity_in_chunks_in_use(), allocated_chunks_words()); 2394 2395 MutexLockerEx fcl(SpaceManager::expand_lock(), 2396 Mutex::_no_safepoint_check_flag); 2397 2398 chunk_manager()->slow_locked_verify(); 2399 2400 dec_total_from_size_metrics(); 2401 2402 Log(gc, metaspace, freelist) log; 2403 if (log.is_trace()) { 2404 log.trace("~SpaceManager(): " PTR_FORMAT, p2i(this)); 2405 ResourceMark rm; 2406 LogStream ls(log.trace()); 2407 locked_print_chunks_in_use_on(&ls); 2408 if (block_freelists() != NULL) { 2409 block_freelists()->print_on(&ls); 2410 } 2411 } 2412 2413 // Add all the chunks in use by this space manager 2414 // to the global list of free chunks. 2415 2416 // Follow each list of chunks-in-use and add them to the 2417 // free lists. Each list is NULL terminated. 2418 2419 for (ChunkIndex i = ZeroIndex; i <= HumongousIndex; i = next_chunk_index(i)) { 2420 Metachunk* chunks = chunks_in_use(i); 2421 chunk_manager()->return_chunk_list(i, chunks); 2422 set_chunks_in_use(i, NULL); 2423 } 2424 2425 chunk_manager()->slow_locked_verify(); 2426 2427 if (_block_freelists != NULL) { 2428 delete _block_freelists; 2429 } 2430 } 2431 2432 void SpaceManager::deallocate(MetaWord* p, size_t word_size) { 2433 assert_lock_strong(_lock); 2434 // Allocations and deallocations are in raw_word_size 2435 size_t raw_word_size = get_allocation_word_size(word_size); 2436 // Lazily create a block_freelist 2437 if (block_freelists() == NULL) { 2438 _block_freelists = new BlockFreelist(); 2439 } 2440 block_freelists()->return_block(p, raw_word_size); 2441 } 2442 2443 // Adds a chunk to the list of chunks in use. 2444 void SpaceManager::add_chunk(Metachunk* new_chunk, bool make_current) { 2445 2446 assert(new_chunk != NULL, "Should not be NULL"); 2447 assert(new_chunk->next() == NULL, "Should not be on a list"); 2448 2449 new_chunk->reset_empty(); 2450 2451 // Find the correct list and and set the current 2452 // chunk for that list. 2453 ChunkIndex index = chunk_manager()->list_index(new_chunk->word_size()); 2454 2455 if (index != HumongousIndex) { 2456 retire_current_chunk(); 2457 set_current_chunk(new_chunk); 2458 new_chunk->set_next(chunks_in_use(index)); 2459 set_chunks_in_use(index, new_chunk); 2460 } else { 2461 // For null class loader data and DumpSharedSpaces, the first chunk isn't 2462 // small, so small will be null. Link this first chunk as the current 2463 // chunk. 2464 if (make_current) { 2465 // Set as the current chunk but otherwise treat as a humongous chunk. 2466 set_current_chunk(new_chunk); 2467 } 2468 // Link at head. The _current_chunk only points to a humongous chunk for 2469 // the null class loader metaspace (class and data virtual space managers) 2470 // any humongous chunks so will not point to the tail 2471 // of the humongous chunks list. 2472 new_chunk->set_next(chunks_in_use(HumongousIndex)); 2473 set_chunks_in_use(HumongousIndex, new_chunk); 2474 2475 assert(new_chunk->word_size() > medium_chunk_size(), "List inconsistency"); 2476 } 2477 2478 // Add to the running sum of capacity 2479 inc_size_metrics(new_chunk->word_size()); 2480 2481 assert(new_chunk->is_empty(), "Not ready for reuse"); 2482 Log(gc, metaspace, freelist) log; 2483 if (log.is_trace()) { 2484 log.trace("SpaceManager::add_chunk: " SIZE_FORMAT ") ", sum_count_in_chunks_in_use()); 2485 ResourceMark rm; 2486 LogStream ls(log.trace()); 2487 new_chunk->print_on(&ls); 2488 chunk_manager()->locked_print_free_chunks(&ls); 2489 } 2490 } 2491 2492 void SpaceManager::retire_current_chunk() { 2493 if (current_chunk() != NULL) { 2494 size_t remaining_words = current_chunk()->free_word_size(); 2495 if (remaining_words >= BlockFreelist::min_dictionary_size()) { 2496 MetaWord* ptr = current_chunk()->allocate(remaining_words); 2497 deallocate(ptr, remaining_words); 2498 inc_used_metrics(remaining_words); 2499 } 2500 } 2501 } 2502 2503 Metachunk* SpaceManager::get_new_chunk(size_t chunk_word_size) { 2504 // Get a chunk from the chunk freelist 2505 Metachunk* next = chunk_manager()->chunk_freelist_allocate(chunk_word_size); 2506 2507 if (next == NULL) { 2508 next = vs_list()->get_new_chunk(chunk_word_size, 2509 medium_chunk_bunch()); 2510 } 2511 2512 Log(gc, metaspace, alloc) log; 2513 if (log.is_debug() && next != NULL && 2514 SpaceManager::is_humongous(next->word_size())) { 2515 log.debug(" new humongous chunk word size " PTR_FORMAT, next->word_size()); 2516 } 2517 2518 return next; 2519 } 2520 2521 /* 2522 * The policy is to allocate up to _small_chunk_limit small chunks 2523 * after which only medium chunks are allocated. This is done to 2524 * reduce fragmentation. In some cases, this can result in a lot 2525 * of small chunks being allocated to the point where it's not 2526 * possible to expand. If this happens, there may be no medium chunks 2527 * available and OOME would be thrown. Instead of doing that, 2528 * if the allocation request size fits in a small chunk, an attempt 2529 * will be made to allocate a small chunk. 2530 */ 2531 MetaWord* SpaceManager::get_small_chunk_and_allocate(size_t word_size) { 2532 size_t raw_word_size = get_allocation_word_size(word_size); 2533 2534 if (raw_word_size + Metachunk::overhead() > small_chunk_size()) { 2535 return NULL; 2536 } 2537 2538 MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag); 2539 MutexLockerEx cl1(expand_lock(), Mutex::_no_safepoint_check_flag); 2540 2541 Metachunk* chunk = chunk_manager()->chunk_freelist_allocate(small_chunk_size()); 2542 2543 MetaWord* mem = NULL; 2544 2545 if (chunk != NULL) { 2546 // Add chunk to the in-use chunk list and do an allocation from it. 2547 // Add to this manager's list of chunks in use. 2548 add_chunk(chunk, false); 2549 mem = chunk->allocate(raw_word_size); 2550 2551 inc_used_metrics(raw_word_size); 2552 2553 // Track metaspace memory usage statistic. 2554 track_metaspace_memory_usage(); 2555 } 2556 2557 return mem; 2558 } 2559 2560 MetaWord* SpaceManager::allocate(size_t word_size) { 2561 MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag); 2562 size_t raw_word_size = get_allocation_word_size(word_size); 2563 BlockFreelist* fl = block_freelists(); 2564 MetaWord* p = NULL; 2565 // Allocation from the dictionary is expensive in the sense that 2566 // the dictionary has to be searched for a size. Don't allocate 2567 // from the dictionary until it starts to get fat. Is this 2568 // a reasonable policy? Maybe an skinny dictionary is fast enough 2569 // for allocations. Do some profiling. JJJ 2570 if (fl != NULL && fl->total_size() > allocation_from_dictionary_limit) { 2571 p = fl->get_block(raw_word_size); 2572 } 2573 if (p == NULL) { 2574 p = allocate_work(raw_word_size); 2575 } 2576 2577 return p; 2578 } 2579 2580 // Returns the address of spaced allocated for "word_size". 2581 // This methods does not know about blocks (Metablocks) 2582 MetaWord* SpaceManager::allocate_work(size_t word_size) { 2583 assert_lock_strong(_lock); 2584 #ifdef ASSERT 2585 if (Metadebug::test_metadata_failure()) { 2586 return NULL; 2587 } 2588 #endif 2589 // Is there space in the current chunk? 2590 MetaWord* result = NULL; 2591 2592 // For DumpSharedSpaces, only allocate out of the current chunk which is 2593 // never null because we gave it the size we wanted. Caller reports out 2594 // of memory if this returns null. 2595 if (DumpSharedSpaces) { 2596 assert(current_chunk() != NULL, "should never happen"); 2597 inc_used_metrics(word_size); 2598 return current_chunk()->allocate(word_size); // caller handles null result 2599 } 2600 2601 if (current_chunk() != NULL) { 2602 result = current_chunk()->allocate(word_size); 2603 } 2604 2605 if (result == NULL) { 2606 result = grow_and_allocate(word_size); 2607 } 2608 2609 if (result != NULL) { 2610 inc_used_metrics(word_size); 2611 assert(result != (MetaWord*) chunks_in_use(MediumIndex), 2612 "Head of the list is being allocated"); 2613 } 2614 2615 return result; 2616 } 2617 2618 void SpaceManager::verify() { 2619 // If there are blocks in the dictionary, then 2620 // verification of chunks does not work since 2621 // being in the dictionary alters a chunk. 2622 if (block_freelists() != NULL && block_freelists()->total_size() == 0) { 2623 for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) { 2624 Metachunk* curr = chunks_in_use(i); 2625 while (curr != NULL) { 2626 curr->verify(); 2627 verify_chunk_size(curr); 2628 curr = curr->next(); 2629 } 2630 } 2631 } 2632 } 2633 2634 void SpaceManager::verify_chunk_size(Metachunk* chunk) { 2635 assert(is_humongous(chunk->word_size()) || 2636 chunk->word_size() == medium_chunk_size() || 2637 chunk->word_size() == small_chunk_size() || 2638 chunk->word_size() == specialized_chunk_size(), 2639 "Chunk size is wrong"); 2640 return; 2641 } 2642 2643 #ifdef ASSERT 2644 void SpaceManager::verify_allocated_blocks_words() { 2645 // Verification is only guaranteed at a safepoint. 2646 assert(SafepointSynchronize::is_at_safepoint() || !Universe::is_fully_initialized(), 2647 "Verification can fail if the applications is running"); 2648 assert(allocated_blocks_words() == sum_used_in_chunks_in_use(), 2649 "allocation total is not consistent " SIZE_FORMAT 2650 " vs " SIZE_FORMAT, 2651 allocated_blocks_words(), sum_used_in_chunks_in_use()); 2652 } 2653 2654 #endif 2655 2656 void SpaceManager::dump(outputStream* const out) const { 2657 size_t curr_total = 0; 2658 size_t waste = 0; 2659 uint i = 0; 2660 size_t used = 0; 2661 size_t capacity = 0; 2662 2663 // Add up statistics for all chunks in this SpaceManager. 2664 for (ChunkIndex index = ZeroIndex; 2665 index < NumberOfInUseLists; 2666 index = next_chunk_index(index)) { 2667 for (Metachunk* curr = chunks_in_use(index); 2668 curr != NULL; 2669 curr = curr->next()) { 2670 out->print("%d) ", i++); 2671 curr->print_on(out); 2672 curr_total += curr->word_size(); 2673 used += curr->used_word_size(); 2674 capacity += curr->word_size(); 2675 waste += curr->free_word_size() + curr->overhead();; 2676 } 2677 } 2678 2679 if (log_is_enabled(Trace, gc, metaspace, freelist)) { 2680 if (block_freelists() != NULL) block_freelists()->print_on(out); 2681 } 2682 2683 size_t free = current_chunk() == NULL ? 0 : current_chunk()->free_word_size(); 2684 // Free space isn't wasted. 2685 waste -= free; 2686 2687 out->print_cr("total of all chunks " SIZE_FORMAT " used " SIZE_FORMAT 2688 " free " SIZE_FORMAT " capacity " SIZE_FORMAT 2689 " waste " SIZE_FORMAT, curr_total, used, free, capacity, waste); 2690 } 2691 2692 // MetaspaceAux 2693 2694 2695 size_t MetaspaceAux::_capacity_words[] = {0, 0}; 2696 size_t MetaspaceAux::_used_words[] = {0, 0}; 2697 2698 size_t MetaspaceAux::free_bytes(Metaspace::MetadataType mdtype) { 2699 VirtualSpaceList* list = Metaspace::get_space_list(mdtype); 2700 return list == NULL ? 0 : list->free_bytes(); 2701 } 2702 2703 size_t MetaspaceAux::free_bytes() { 2704 return free_bytes(Metaspace::ClassType) + free_bytes(Metaspace::NonClassType); 2705 } 2706 2707 void MetaspaceAux::dec_capacity(Metaspace::MetadataType mdtype, size_t words) { 2708 assert_lock_strong(SpaceManager::expand_lock()); 2709 assert(words <= capacity_words(mdtype), 2710 "About to decrement below 0: words " SIZE_FORMAT 2711 " is greater than _capacity_words[%u] " SIZE_FORMAT, 2712 words, mdtype, capacity_words(mdtype)); 2713 _capacity_words[mdtype] -= words; 2714 } 2715 2716 void MetaspaceAux::inc_capacity(Metaspace::MetadataType mdtype, size_t words) { 2717 assert_lock_strong(SpaceManager::expand_lock()); 2718 // Needs to be atomic 2719 _capacity_words[mdtype] += words; 2720 } 2721 2722 void MetaspaceAux::dec_used(Metaspace::MetadataType mdtype, size_t words) { 2723 assert(words <= used_words(mdtype), 2724 "About to decrement below 0: words " SIZE_FORMAT 2725 " is greater than _used_words[%u] " SIZE_FORMAT, 2726 words, mdtype, used_words(mdtype)); 2727 // For CMS deallocation of the Metaspaces occurs during the 2728 // sweep which is a concurrent phase. Protection by the expand_lock() 2729 // is not enough since allocation is on a per Metaspace basis 2730 // and protected by the Metaspace lock. 2731 jlong minus_words = (jlong) - (jlong) words; 2732 Atomic::add_ptr(minus_words, &_used_words[mdtype]); 2733 } 2734 2735 void MetaspaceAux::inc_used(Metaspace::MetadataType mdtype, size_t words) { 2736 // _used_words tracks allocations for 2737 // each piece of metadata. Those allocations are 2738 // generally done concurrently by different application 2739 // threads so must be done atomically. 2740 Atomic::add_ptr(words, &_used_words[mdtype]); 2741 } 2742 2743 size_t MetaspaceAux::used_bytes_slow(Metaspace::MetadataType mdtype) { 2744 size_t used = 0; 2745 ClassLoaderDataGraphMetaspaceIterator iter; 2746 while (iter.repeat()) { 2747 Metaspace* msp = iter.get_next(); 2748 // Sum allocated_blocks_words for each metaspace 2749 if (msp != NULL) { 2750 used += msp->used_words_slow(mdtype); 2751 } 2752 } 2753 return used * BytesPerWord; 2754 } 2755 2756 size_t MetaspaceAux::free_bytes_slow(Metaspace::MetadataType mdtype) { 2757 size_t free = 0; 2758 ClassLoaderDataGraphMetaspaceIterator iter; 2759 while (iter.repeat()) { 2760 Metaspace* msp = iter.get_next(); 2761 if (msp != NULL) { 2762 free += msp->free_words_slow(mdtype); 2763 } 2764 } 2765 return free * BytesPerWord; 2766 } 2767 2768 size_t MetaspaceAux::capacity_bytes_slow(Metaspace::MetadataType mdtype) { 2769 if ((mdtype == Metaspace::ClassType) && !Metaspace::using_class_space()) { 2770 return 0; 2771 } 2772 // Don't count the space in the freelists. That space will be 2773 // added to the capacity calculation as needed. 2774 size_t capacity = 0; 2775 ClassLoaderDataGraphMetaspaceIterator iter; 2776 while (iter.repeat()) { 2777 Metaspace* msp = iter.get_next(); 2778 if (msp != NULL) { 2779 capacity += msp->capacity_words_slow(mdtype); 2780 } 2781 } 2782 return capacity * BytesPerWord; 2783 } 2784 2785 size_t MetaspaceAux::capacity_bytes_slow() { 2786 #ifdef PRODUCT 2787 // Use capacity_bytes() in PRODUCT instead of this function. 2788 guarantee(false, "Should not call capacity_bytes_slow() in the PRODUCT"); 2789 #endif 2790 size_t class_capacity = capacity_bytes_slow(Metaspace::ClassType); 2791 size_t non_class_capacity = capacity_bytes_slow(Metaspace::NonClassType); 2792 assert(capacity_bytes() == class_capacity + non_class_capacity, 2793 "bad accounting: capacity_bytes() " SIZE_FORMAT 2794 " class_capacity + non_class_capacity " SIZE_FORMAT 2795 " class_capacity " SIZE_FORMAT " non_class_capacity " SIZE_FORMAT, 2796 capacity_bytes(), class_capacity + non_class_capacity, 2797 class_capacity, non_class_capacity); 2798 2799 return class_capacity + non_class_capacity; 2800 } 2801 2802 size_t MetaspaceAux::reserved_bytes(Metaspace::MetadataType mdtype) { 2803 VirtualSpaceList* list = Metaspace::get_space_list(mdtype); 2804 return list == NULL ? 0 : list->reserved_bytes(); 2805 } 2806 2807 size_t MetaspaceAux::committed_bytes(Metaspace::MetadataType mdtype) { 2808 VirtualSpaceList* list = Metaspace::get_space_list(mdtype); 2809 return list == NULL ? 0 : list->committed_bytes(); 2810 } 2811 2812 size_t MetaspaceAux::min_chunk_size_words() { return Metaspace::first_chunk_word_size(); } 2813 2814 size_t MetaspaceAux::free_chunks_total_words(Metaspace::MetadataType mdtype) { 2815 ChunkManager* chunk_manager = Metaspace::get_chunk_manager(mdtype); 2816 if (chunk_manager == NULL) { 2817 return 0; 2818 } 2819 chunk_manager->slow_verify(); 2820 return chunk_manager->free_chunks_total_words(); 2821 } 2822 2823 size_t MetaspaceAux::free_chunks_total_bytes(Metaspace::MetadataType mdtype) { 2824 return free_chunks_total_words(mdtype) * BytesPerWord; 2825 } 2826 2827 size_t MetaspaceAux::free_chunks_total_words() { 2828 return free_chunks_total_words(Metaspace::ClassType) + 2829 free_chunks_total_words(Metaspace::NonClassType); 2830 } 2831 2832 size_t MetaspaceAux::free_chunks_total_bytes() { 2833 return free_chunks_total_words() * BytesPerWord; 2834 } 2835 2836 bool MetaspaceAux::has_chunk_free_list(Metaspace::MetadataType mdtype) { 2837 return Metaspace::get_chunk_manager(mdtype) != NULL; 2838 } 2839 2840 MetaspaceChunkFreeListSummary MetaspaceAux::chunk_free_list_summary(Metaspace::MetadataType mdtype) { 2841 if (!has_chunk_free_list(mdtype)) { 2842 return MetaspaceChunkFreeListSummary(); 2843 } 2844 2845 const ChunkManager* cm = Metaspace::get_chunk_manager(mdtype); 2846 return cm->chunk_free_list_summary(); 2847 } 2848 2849 void MetaspaceAux::print_metaspace_change(size_t prev_metadata_used) { 2850 log_info(gc, metaspace)("Metaspace: " SIZE_FORMAT "K->" SIZE_FORMAT "K(" SIZE_FORMAT "K)", 2851 prev_metadata_used/K, used_bytes()/K, reserved_bytes()/K); 2852 } 2853 2854 void MetaspaceAux::print_on(outputStream* out) { 2855 Metaspace::MetadataType nct = Metaspace::NonClassType; 2856 2857 out->print_cr(" Metaspace " 2858 "used " SIZE_FORMAT "K, " 2859 "capacity " SIZE_FORMAT "K, " 2860 "committed " SIZE_FORMAT "K, " 2861 "reserved " SIZE_FORMAT "K", 2862 used_bytes()/K, 2863 capacity_bytes()/K, 2864 committed_bytes()/K, 2865 reserved_bytes()/K); 2866 2867 if (Metaspace::using_class_space()) { 2868 Metaspace::MetadataType ct = Metaspace::ClassType; 2869 out->print_cr(" class space " 2870 "used " SIZE_FORMAT "K, " 2871 "capacity " SIZE_FORMAT "K, " 2872 "committed " SIZE_FORMAT "K, " 2873 "reserved " SIZE_FORMAT "K", 2874 used_bytes(ct)/K, 2875 capacity_bytes(ct)/K, 2876 committed_bytes(ct)/K, 2877 reserved_bytes(ct)/K); 2878 } 2879 } 2880 2881 // Print information for class space and data space separately. 2882 // This is almost the same as above. 2883 void MetaspaceAux::print_on(outputStream* out, Metaspace::MetadataType mdtype) { 2884 size_t free_chunks_capacity_bytes = free_chunks_total_bytes(mdtype); 2885 size_t capacity_bytes = capacity_bytes_slow(mdtype); 2886 size_t used_bytes = used_bytes_slow(mdtype); 2887 size_t free_bytes = free_bytes_slow(mdtype); 2888 size_t used_and_free = used_bytes + free_bytes + 2889 free_chunks_capacity_bytes; 2890 out->print_cr(" Chunk accounting: used in chunks " SIZE_FORMAT 2891 "K + unused in chunks " SIZE_FORMAT "K + " 2892 " capacity in free chunks " SIZE_FORMAT "K = " SIZE_FORMAT 2893 "K capacity in allocated chunks " SIZE_FORMAT "K", 2894 used_bytes / K, 2895 free_bytes / K, 2896 free_chunks_capacity_bytes / K, 2897 used_and_free / K, 2898 capacity_bytes / K); 2899 // Accounting can only be correct if we got the values during a safepoint 2900 assert(!SafepointSynchronize::is_at_safepoint() || used_and_free == capacity_bytes, "Accounting is wrong"); 2901 } 2902 2903 // Print total fragmentation for class metaspaces 2904 void MetaspaceAux::print_class_waste(outputStream* out) { 2905 assert(Metaspace::using_class_space(), "class metaspace not used"); 2906 size_t cls_specialized_waste = 0, cls_small_waste = 0, cls_medium_waste = 0; 2907 size_t cls_specialized_count = 0, cls_small_count = 0, cls_medium_count = 0, cls_humongous_count = 0; 2908 ClassLoaderDataGraphMetaspaceIterator iter; 2909 while (iter.repeat()) { 2910 Metaspace* msp = iter.get_next(); 2911 if (msp != NULL) { 2912 cls_specialized_waste += msp->class_vsm()->sum_waste_in_chunks_in_use(SpecializedIndex); 2913 cls_specialized_count += msp->class_vsm()->sum_count_in_chunks_in_use(SpecializedIndex); 2914 cls_small_waste += msp->class_vsm()->sum_waste_in_chunks_in_use(SmallIndex); 2915 cls_small_count += msp->class_vsm()->sum_count_in_chunks_in_use(SmallIndex); 2916 cls_medium_waste += msp->class_vsm()->sum_waste_in_chunks_in_use(MediumIndex); 2917 cls_medium_count += msp->class_vsm()->sum_count_in_chunks_in_use(MediumIndex); 2918 cls_humongous_count += msp->class_vsm()->sum_count_in_chunks_in_use(HumongousIndex); 2919 } 2920 } 2921 out->print_cr(" class: " SIZE_FORMAT " specialized(s) " SIZE_FORMAT ", " 2922 SIZE_FORMAT " small(s) " SIZE_FORMAT ", " 2923 SIZE_FORMAT " medium(s) " SIZE_FORMAT ", " 2924 "large count " SIZE_FORMAT, 2925 cls_specialized_count, cls_specialized_waste, 2926 cls_small_count, cls_small_waste, 2927 cls_medium_count, cls_medium_waste, cls_humongous_count); 2928 } 2929 2930 // Print total fragmentation for data and class metaspaces separately 2931 void MetaspaceAux::print_waste(outputStream* out) { 2932 size_t specialized_waste = 0, small_waste = 0, medium_waste = 0; 2933 size_t specialized_count = 0, small_count = 0, medium_count = 0, humongous_count = 0; 2934 2935 ClassLoaderDataGraphMetaspaceIterator iter; 2936 while (iter.repeat()) { 2937 Metaspace* msp = iter.get_next(); 2938 if (msp != NULL) { 2939 specialized_waste += msp->vsm()->sum_waste_in_chunks_in_use(SpecializedIndex); 2940 specialized_count += msp->vsm()->sum_count_in_chunks_in_use(SpecializedIndex); 2941 small_waste += msp->vsm()->sum_waste_in_chunks_in_use(SmallIndex); 2942 small_count += msp->vsm()->sum_count_in_chunks_in_use(SmallIndex); 2943 medium_waste += msp->vsm()->sum_waste_in_chunks_in_use(MediumIndex); 2944 medium_count += msp->vsm()->sum_count_in_chunks_in_use(MediumIndex); 2945 humongous_count += msp->vsm()->sum_count_in_chunks_in_use(HumongousIndex); 2946 } 2947 } 2948 out->print_cr("Total fragmentation waste (words) doesn't count free space"); 2949 out->print_cr(" data: " SIZE_FORMAT " specialized(s) " SIZE_FORMAT ", " 2950 SIZE_FORMAT " small(s) " SIZE_FORMAT ", " 2951 SIZE_FORMAT " medium(s) " SIZE_FORMAT ", " 2952 "large count " SIZE_FORMAT, 2953 specialized_count, specialized_waste, small_count, 2954 small_waste, medium_count, medium_waste, humongous_count); 2955 if (Metaspace::using_class_space()) { 2956 print_class_waste(out); 2957 } 2958 } 2959 2960 // Dump global metaspace things from the end of ClassLoaderDataGraph 2961 void MetaspaceAux::dump(outputStream* out) { 2962 out->print_cr("All Metaspace:"); 2963 out->print("data space: "); print_on(out, Metaspace::NonClassType); 2964 out->print("class space: "); print_on(out, Metaspace::ClassType); 2965 print_waste(out); 2966 } 2967 2968 void MetaspaceAux::verify_free_chunks() { 2969 Metaspace::chunk_manager_metadata()->verify(); 2970 if (Metaspace::using_class_space()) { 2971 Metaspace::chunk_manager_class()->verify(); 2972 } 2973 } 2974 2975 void MetaspaceAux::verify_capacity() { 2976 #ifdef ASSERT 2977 size_t running_sum_capacity_bytes = capacity_bytes(); 2978 // For purposes of the running sum of capacity, verify against capacity 2979 size_t capacity_in_use_bytes = capacity_bytes_slow(); 2980 assert(running_sum_capacity_bytes == capacity_in_use_bytes, 2981 "capacity_words() * BytesPerWord " SIZE_FORMAT 2982 " capacity_bytes_slow()" SIZE_FORMAT, 2983 running_sum_capacity_bytes, capacity_in_use_bytes); 2984 for (Metaspace::MetadataType i = Metaspace::ClassType; 2985 i < Metaspace:: MetadataTypeCount; 2986 i = (Metaspace::MetadataType)(i + 1)) { 2987 size_t capacity_in_use_bytes = capacity_bytes_slow(i); 2988 assert(capacity_bytes(i) == capacity_in_use_bytes, 2989 "capacity_bytes(%u) " SIZE_FORMAT 2990 " capacity_bytes_slow(%u)" SIZE_FORMAT, 2991 i, capacity_bytes(i), i, capacity_in_use_bytes); 2992 } 2993 #endif 2994 } 2995 2996 void MetaspaceAux::verify_used() { 2997 #ifdef ASSERT 2998 size_t running_sum_used_bytes = used_bytes(); 2999 // For purposes of the running sum of used, verify against used 3000 size_t used_in_use_bytes = used_bytes_slow(); 3001 assert(used_bytes() == used_in_use_bytes, 3002 "used_bytes() " SIZE_FORMAT 3003 " used_bytes_slow()" SIZE_FORMAT, 3004 used_bytes(), used_in_use_bytes); 3005 for (Metaspace::MetadataType i = Metaspace::ClassType; 3006 i < Metaspace:: MetadataTypeCount; 3007 i = (Metaspace::MetadataType)(i + 1)) { 3008 size_t used_in_use_bytes = used_bytes_slow(i); 3009 assert(used_bytes(i) == used_in_use_bytes, 3010 "used_bytes(%u) " SIZE_FORMAT 3011 " used_bytes_slow(%u)" SIZE_FORMAT, 3012 i, used_bytes(i), i, used_in_use_bytes); 3013 } 3014 #endif 3015 } 3016 3017 void MetaspaceAux::verify_metrics() { 3018 verify_capacity(); 3019 verify_used(); 3020 } 3021 3022 3023 // Metaspace methods 3024 3025 size_t Metaspace::_first_chunk_word_size = 0; 3026 size_t Metaspace::_first_class_chunk_word_size = 0; 3027 3028 size_t Metaspace::_commit_alignment = 0; 3029 size_t Metaspace::_reserve_alignment = 0; 3030 3031 Metaspace::Metaspace(Mutex* lock, MetaspaceType type) { 3032 initialize(lock, type); 3033 } 3034 3035 Metaspace::~Metaspace() { 3036 delete _vsm; 3037 if (using_class_space()) { 3038 delete _class_vsm; 3039 } 3040 } 3041 3042 VirtualSpaceList* Metaspace::_space_list = NULL; 3043 VirtualSpaceList* Metaspace::_class_space_list = NULL; 3044 3045 ChunkManager* Metaspace::_chunk_manager_metadata = NULL; 3046 ChunkManager* Metaspace::_chunk_manager_class = NULL; 3047 3048 #define VIRTUALSPACEMULTIPLIER 2 3049 3050 #ifdef _LP64 3051 static const uint64_t UnscaledClassSpaceMax = (uint64_t(max_juint) + 1); 3052 3053 void Metaspace::set_narrow_klass_base_and_shift(address metaspace_base, address cds_base) { 3054 // Figure out the narrow_klass_base and the narrow_klass_shift. The 3055 // narrow_klass_base is the lower of the metaspace base and the cds base 3056 // (if cds is enabled). The narrow_klass_shift depends on the distance 3057 // between the lower base and higher address. 3058 address lower_base; 3059 address higher_address; 3060 #if INCLUDE_CDS 3061 if (UseSharedSpaces) { 3062 higher_address = MAX2((address)(cds_base + FileMapInfo::shared_spaces_size()), 3063 (address)(metaspace_base + compressed_class_space_size())); 3064 lower_base = MIN2(metaspace_base, cds_base); 3065 } else 3066 #endif 3067 { 3068 higher_address = metaspace_base + compressed_class_space_size(); 3069 lower_base = metaspace_base; 3070 3071 uint64_t klass_encoding_max = UnscaledClassSpaceMax << LogKlassAlignmentInBytes; 3072 // If compressed class space fits in lower 32G, we don't need a base. 3073 if (higher_address <= (address)klass_encoding_max) { 3074 lower_base = 0; // Effectively lower base is zero. 3075 } 3076 } 3077 3078 Universe::set_narrow_klass_base(lower_base); 3079 3080 if ((uint64_t)(higher_address - lower_base) <= UnscaledClassSpaceMax) { 3081 Universe::set_narrow_klass_shift(0); 3082 } else { 3083 assert(!UseSharedSpaces, "Cannot shift with UseSharedSpaces"); 3084 Universe::set_narrow_klass_shift(LogKlassAlignmentInBytes); 3085 } 3086 AOTLoader::set_narrow_klass_shift(); 3087 } 3088 3089 #if INCLUDE_CDS 3090 // Return TRUE if the specified metaspace_base and cds_base are close enough 3091 // to work with compressed klass pointers. 3092 bool Metaspace::can_use_cds_with_metaspace_addr(char* metaspace_base, address cds_base) { 3093 assert(cds_base != 0 && UseSharedSpaces, "Only use with CDS"); 3094 assert(UseCompressedClassPointers, "Only use with CompressedKlassPtrs"); 3095 address lower_base = MIN2((address)metaspace_base, cds_base); 3096 address higher_address = MAX2((address)(cds_base + FileMapInfo::shared_spaces_size()), 3097 (address)(metaspace_base + compressed_class_space_size())); 3098 return ((uint64_t)(higher_address - lower_base) <= UnscaledClassSpaceMax); 3099 } 3100 #endif 3101 3102 // Try to allocate the metaspace at the requested addr. 3103 void Metaspace::allocate_metaspace_compressed_klass_ptrs(char* requested_addr, address cds_base) { 3104 assert(using_class_space(), "called improperly"); 3105 assert(UseCompressedClassPointers, "Only use with CompressedKlassPtrs"); 3106 assert(compressed_class_space_size() < KlassEncodingMetaspaceMax, 3107 "Metaspace size is too big"); 3108 assert_is_ptr_aligned(requested_addr, _reserve_alignment); 3109 assert_is_ptr_aligned(cds_base, _reserve_alignment); 3110 assert_is_size_aligned(compressed_class_space_size(), _reserve_alignment); 3111 3112 // Don't use large pages for the class space. 3113 bool large_pages = false; 3114 3115 #if !(defined(AARCH64) || defined(AIX)) 3116 ReservedSpace metaspace_rs = ReservedSpace(compressed_class_space_size(), 3117 _reserve_alignment, 3118 large_pages, 3119 requested_addr); 3120 #else // AARCH64 3121 ReservedSpace metaspace_rs; 3122 3123 // Our compressed klass pointers may fit nicely into the lower 32 3124 // bits. 3125 if ((uint64_t)requested_addr + compressed_class_space_size() < 4*G) { 3126 metaspace_rs = ReservedSpace(compressed_class_space_size(), 3127 _reserve_alignment, 3128 large_pages, 3129 requested_addr); 3130 } 3131 3132 if (! metaspace_rs.is_reserved()) { 3133 // Aarch64: Try to align metaspace so that we can decode a compressed 3134 // klass with a single MOVK instruction. We can do this iff the 3135 // compressed class base is a multiple of 4G. 3136 // Aix: Search for a place where we can find memory. If we need to load 3137 // the base, 4G alignment is helpful, too. 3138 size_t increment = AARCH64_ONLY(4*)G; 3139 for (char *a = (char*)align_ptr_up(requested_addr, increment); 3140 a < (char*)(1024*G); 3141 a += increment) { 3142 if (a == (char *)(32*G)) { 3143 // Go faster from here on. Zero-based is no longer possible. 3144 increment = 4*G; 3145 } 3146 3147 #if INCLUDE_CDS 3148 if (UseSharedSpaces 3149 && ! can_use_cds_with_metaspace_addr(a, cds_base)) { 3150 // We failed to find an aligned base that will reach. Fall 3151 // back to using our requested addr. 3152 metaspace_rs = ReservedSpace(compressed_class_space_size(), 3153 _reserve_alignment, 3154 large_pages, 3155 requested_addr); 3156 break; 3157 } 3158 #endif 3159 3160 metaspace_rs = ReservedSpace(compressed_class_space_size(), 3161 _reserve_alignment, 3162 large_pages, 3163 a); 3164 if (metaspace_rs.is_reserved()) 3165 break; 3166 } 3167 } 3168 3169 #endif // AARCH64 3170 3171 if (!metaspace_rs.is_reserved()) { 3172 #if INCLUDE_CDS 3173 if (UseSharedSpaces) { 3174 size_t increment = align_size_up(1*G, _reserve_alignment); 3175 3176 // Keep trying to allocate the metaspace, increasing the requested_addr 3177 // by 1GB each time, until we reach an address that will no longer allow 3178 // use of CDS with compressed klass pointers. 3179 char *addr = requested_addr; 3180 while (!metaspace_rs.is_reserved() && (addr + increment > addr) && 3181 can_use_cds_with_metaspace_addr(addr + increment, cds_base)) { 3182 addr = addr + increment; 3183 metaspace_rs = ReservedSpace(compressed_class_space_size(), 3184 _reserve_alignment, large_pages, addr); 3185 } 3186 } 3187 #endif 3188 // If no successful allocation then try to allocate the space anywhere. If 3189 // that fails then OOM doom. At this point we cannot try allocating the 3190 // metaspace as if UseCompressedClassPointers is off because too much 3191 // initialization has happened that depends on UseCompressedClassPointers. 3192 // So, UseCompressedClassPointers cannot be turned off at this point. 3193 if (!metaspace_rs.is_reserved()) { 3194 metaspace_rs = ReservedSpace(compressed_class_space_size(), 3195 _reserve_alignment, large_pages); 3196 if (!metaspace_rs.is_reserved()) { 3197 vm_exit_during_initialization(err_msg("Could not allocate metaspace: " SIZE_FORMAT " bytes", 3198 compressed_class_space_size())); 3199 } 3200 } 3201 } 3202 3203 // If we got here then the metaspace got allocated. 3204 MemTracker::record_virtual_memory_type((address)metaspace_rs.base(), mtClass); 3205 3206 #if INCLUDE_CDS 3207 // Verify that we can use shared spaces. Otherwise, turn off CDS. 3208 if (UseSharedSpaces && !can_use_cds_with_metaspace_addr(metaspace_rs.base(), cds_base)) { 3209 FileMapInfo::stop_sharing_and_unmap( 3210 "Could not allocate metaspace at a compatible address"); 3211 } 3212 #endif 3213 set_narrow_klass_base_and_shift((address)metaspace_rs.base(), 3214 UseSharedSpaces ? (address)cds_base : 0); 3215 3216 initialize_class_space(metaspace_rs); 3217 3218 LogTarget(Trace, gc, metaspace) lt; 3219 if (lt.is_enabled()) { 3220 ResourceMark rm; 3221 LogStream ls(lt); 3222 print_compressed_class_space(&ls, requested_addr); 3223 } 3224 } 3225 3226 void Metaspace::print_compressed_class_space(outputStream* st, const char* requested_addr) { 3227 st->print_cr("Narrow klass base: " PTR_FORMAT ", Narrow klass shift: %d", 3228 p2i(Universe::narrow_klass_base()), Universe::narrow_klass_shift()); 3229 if (_class_space_list != NULL) { 3230 address base = (address)_class_space_list->current_virtual_space()->bottom(); 3231 st->print("Compressed class space size: " SIZE_FORMAT " Address: " PTR_FORMAT, 3232 compressed_class_space_size(), p2i(base)); 3233 if (requested_addr != 0) { 3234 st->print(" Req Addr: " PTR_FORMAT, p2i(requested_addr)); 3235 } 3236 st->cr(); 3237 } 3238 } 3239 3240 // For UseCompressedClassPointers the class space is reserved above the top of 3241 // the Java heap. The argument passed in is at the base of the compressed space. 3242 void Metaspace::initialize_class_space(ReservedSpace rs) { 3243 // The reserved space size may be bigger because of alignment, esp with UseLargePages 3244 assert(rs.size() >= CompressedClassSpaceSize, 3245 SIZE_FORMAT " != " SIZE_FORMAT, rs.size(), CompressedClassSpaceSize); 3246 assert(using_class_space(), "Must be using class space"); 3247 _class_space_list = new VirtualSpaceList(rs); 3248 _chunk_manager_class = new ChunkManager(ClassSpecializedChunk, ClassSmallChunk, ClassMediumChunk); 3249 3250 if (!_class_space_list->initialization_succeeded()) { 3251 vm_exit_during_initialization("Failed to setup compressed class space virtual space list."); 3252 } 3253 } 3254 3255 #endif 3256 3257 void Metaspace::ergo_initialize() { 3258 if (DumpSharedSpaces) { 3259 // Using large pages when dumping the shared archive is currently not implemented. 3260 FLAG_SET_ERGO(bool, UseLargePagesInMetaspace, false); 3261 } 3262 3263 size_t page_size = os::vm_page_size(); 3264 if (UseLargePages && UseLargePagesInMetaspace) { 3265 page_size = os::large_page_size(); 3266 } 3267 3268 _commit_alignment = page_size; 3269 _reserve_alignment = MAX2(page_size, (size_t)os::vm_allocation_granularity()); 3270 3271 // Do not use FLAG_SET_ERGO to update MaxMetaspaceSize, since this will 3272 // override if MaxMetaspaceSize was set on the command line or not. 3273 // This information is needed later to conform to the specification of the 3274 // java.lang.management.MemoryUsage API. 3275 // 3276 // Ideally, we would be able to set the default value of MaxMetaspaceSize in 3277 // globals.hpp to the aligned value, but this is not possible, since the 3278 // alignment depends on other flags being parsed. 3279 MaxMetaspaceSize = align_size_down_bounded(MaxMetaspaceSize, _reserve_alignment); 3280 3281 if (MetaspaceSize > MaxMetaspaceSize) { 3282 MetaspaceSize = MaxMetaspaceSize; 3283 } 3284 3285 MetaspaceSize = align_size_down_bounded(MetaspaceSize, _commit_alignment); 3286 3287 assert(MetaspaceSize <= MaxMetaspaceSize, "MetaspaceSize should be limited by MaxMetaspaceSize"); 3288 3289 MinMetaspaceExpansion = align_size_down_bounded(MinMetaspaceExpansion, _commit_alignment); 3290 MaxMetaspaceExpansion = align_size_down_bounded(MaxMetaspaceExpansion, _commit_alignment); 3291 3292 CompressedClassSpaceSize = align_size_down_bounded(CompressedClassSpaceSize, _reserve_alignment); 3293 set_compressed_class_space_size(CompressedClassSpaceSize); 3294 } 3295 3296 void Metaspace::global_initialize() { 3297 MetaspaceGC::initialize(); 3298 3299 // Initialize the alignment for shared spaces. 3300 int max_alignment = os::vm_allocation_granularity(); 3301 size_t cds_total = 0; 3302 3303 MetaspaceShared::set_max_alignment(max_alignment); 3304 3305 if (DumpSharedSpaces) { 3306 #if INCLUDE_CDS 3307 MetaspaceShared::estimate_regions_size(); 3308 3309 SharedReadOnlySize = align_size_up(SharedReadOnlySize, max_alignment); 3310 SharedReadWriteSize = align_size_up(SharedReadWriteSize, max_alignment); 3311 SharedMiscDataSize = align_size_up(SharedMiscDataSize, max_alignment); 3312 SharedMiscCodeSize = align_size_up(SharedMiscCodeSize, max_alignment); 3313 3314 // Initialize with the sum of the shared space sizes. The read-only 3315 // and read write metaspace chunks will be allocated out of this and the 3316 // remainder is the misc code and data chunks. 3317 cds_total = FileMapInfo::shared_spaces_size(); 3318 cds_total = align_size_up(cds_total, _reserve_alignment); 3319 _space_list = new VirtualSpaceList(cds_total/wordSize); 3320 _chunk_manager_metadata = new ChunkManager(SpecializedChunk, SmallChunk, MediumChunk); 3321 3322 if (!_space_list->initialization_succeeded()) { 3323 vm_exit_during_initialization("Unable to dump shared archive.", NULL); 3324 } 3325 3326 #ifdef _LP64 3327 if (cds_total + compressed_class_space_size() > UnscaledClassSpaceMax) { 3328 vm_exit_during_initialization("Unable to dump shared archive.", 3329 err_msg("Size of archive (" SIZE_FORMAT ") + compressed class space (" 3330 SIZE_FORMAT ") == total (" SIZE_FORMAT ") is larger than compressed " 3331 "klass limit: " UINT64_FORMAT, cds_total, compressed_class_space_size(), 3332 cds_total + compressed_class_space_size(), UnscaledClassSpaceMax)); 3333 } 3334 3335 // Set the compressed klass pointer base so that decoding of these pointers works 3336 // properly when creating the shared archive. 3337 assert(UseCompressedOops && UseCompressedClassPointers, 3338 "UseCompressedOops and UseCompressedClassPointers must be set"); 3339 Universe::set_narrow_klass_base((address)_space_list->current_virtual_space()->bottom()); 3340 log_develop_trace(gc, metaspace)("Setting_narrow_klass_base to Address: " PTR_FORMAT, 3341 p2i(_space_list->current_virtual_space()->bottom())); 3342 3343 Universe::set_narrow_klass_shift(0); 3344 #endif // _LP64 3345 #endif // INCLUDE_CDS 3346 } else { 3347 #if INCLUDE_CDS 3348 if (UseSharedSpaces) { 3349 // If using shared space, open the file that contains the shared space 3350 // and map in the memory before initializing the rest of metaspace (so 3351 // the addresses don't conflict) 3352 address cds_address = NULL; 3353 FileMapInfo* mapinfo = new FileMapInfo(); 3354 3355 // Open the shared archive file, read and validate the header. If 3356 // initialization fails, shared spaces [UseSharedSpaces] are 3357 // disabled and the file is closed. 3358 // Map in spaces now also 3359 if (mapinfo->initialize() && MetaspaceShared::map_shared_spaces(mapinfo)) { 3360 cds_total = FileMapInfo::shared_spaces_size(); 3361 cds_address = (address)mapinfo->header()->region_addr(0); 3362 #ifdef _LP64 3363 if (using_class_space()) { 3364 char* cds_end = (char*)(cds_address + cds_total); 3365 cds_end = (char *)align_ptr_up(cds_end, _reserve_alignment); 3366 // If UseCompressedClassPointers is set then allocate the metaspace area 3367 // above the heap and above the CDS area (if it exists). 3368 allocate_metaspace_compressed_klass_ptrs(cds_end, cds_address); 3369 // Map the shared string space after compressed pointers 3370 // because it relies on compressed class pointers setting to work 3371 mapinfo->map_string_regions(); 3372 } 3373 #endif // _LP64 3374 } else { 3375 assert(!mapinfo->is_open() && !UseSharedSpaces, 3376 "archive file not closed or shared spaces not disabled."); 3377 } 3378 } 3379 #endif // INCLUDE_CDS 3380 3381 #ifdef _LP64 3382 if (!UseSharedSpaces && using_class_space()) { 3383 char* base = (char*)align_ptr_up(Universe::heap()->reserved_region().end(), _reserve_alignment); 3384 allocate_metaspace_compressed_klass_ptrs(base, 0); 3385 } 3386 #endif // _LP64 3387 3388 // Initialize these before initializing the VirtualSpaceList 3389 _first_chunk_word_size = InitialBootClassLoaderMetaspaceSize / BytesPerWord; 3390 _first_chunk_word_size = align_word_size_up(_first_chunk_word_size); 3391 // Make the first class chunk bigger than a medium chunk so it's not put 3392 // on the medium chunk list. The next chunk will be small and progress 3393 // from there. This size calculated by -version. 3394 _first_class_chunk_word_size = MIN2((size_t)MediumChunk*6, 3395 (CompressedClassSpaceSize/BytesPerWord)*2); 3396 _first_class_chunk_word_size = align_word_size_up(_first_class_chunk_word_size); 3397 // Arbitrarily set the initial virtual space to a multiple 3398 // of the boot class loader size. 3399 size_t word_size = VIRTUALSPACEMULTIPLIER * _first_chunk_word_size; 3400 word_size = align_size_up(word_size, Metaspace::reserve_alignment_words()); 3401 3402 // Initialize the list of virtual spaces. 3403 _space_list = new VirtualSpaceList(word_size); 3404 _chunk_manager_metadata = new ChunkManager(SpecializedChunk, SmallChunk, MediumChunk); 3405 3406 if (!_space_list->initialization_succeeded()) { 3407 vm_exit_during_initialization("Unable to setup metadata virtual space list.", NULL); 3408 } 3409 } 3410 3411 _tracer = new MetaspaceTracer(); 3412 } 3413 3414 void Metaspace::post_initialize() { 3415 MetaspaceGC::post_initialize(); 3416 } 3417 3418 void Metaspace::initialize_first_chunk(MetaspaceType type, MetadataType mdtype) { 3419 Metachunk* chunk = get_initialization_chunk(type, mdtype); 3420 if (chunk != NULL) { 3421 // Add to this manager's list of chunks in use and current_chunk(). 3422 get_space_manager(mdtype)->add_chunk(chunk, true); 3423 } 3424 } 3425 3426 Metachunk* Metaspace::get_initialization_chunk(MetaspaceType type, MetadataType mdtype) { 3427 size_t chunk_word_size = get_space_manager(mdtype)->get_initial_chunk_size(type); 3428 3429 // Get a chunk from the chunk freelist 3430 Metachunk* chunk = get_chunk_manager(mdtype)->chunk_freelist_allocate(chunk_word_size); 3431 3432 if (chunk == NULL) { 3433 chunk = get_space_list(mdtype)->get_new_chunk(chunk_word_size, 3434 get_space_manager(mdtype)->medium_chunk_bunch()); 3435 } 3436 3437 // For dumping shared archive, report error if allocation has failed. 3438 if (DumpSharedSpaces && chunk == NULL) { 3439 report_insufficient_metaspace(MetaspaceAux::committed_bytes() + chunk_word_size * BytesPerWord); 3440 } 3441 3442 return chunk; 3443 } 3444 3445 void Metaspace::verify_global_initialization() { 3446 assert(space_list() != NULL, "Metadata VirtualSpaceList has not been initialized"); 3447 assert(chunk_manager_metadata() != NULL, "Metadata ChunkManager has not been initialized"); 3448 3449 if (using_class_space()) { 3450 assert(class_space_list() != NULL, "Class VirtualSpaceList has not been initialized"); 3451 assert(chunk_manager_class() != NULL, "Class ChunkManager has not been initialized"); 3452 } 3453 } 3454 3455 void Metaspace::initialize(Mutex* lock, MetaspaceType type) { 3456 verify_global_initialization(); 3457 3458 // Allocate SpaceManager for metadata objects. 3459 _vsm = new SpaceManager(NonClassType, lock); 3460 3461 if (using_class_space()) { 3462 // Allocate SpaceManager for classes. 3463 _class_vsm = new SpaceManager(ClassType, lock); 3464 } 3465 3466 MutexLockerEx cl(SpaceManager::expand_lock(), Mutex::_no_safepoint_check_flag); 3467 3468 // Allocate chunk for metadata objects 3469 initialize_first_chunk(type, NonClassType); 3470 3471 // Allocate chunk for class metadata objects 3472 if (using_class_space()) { 3473 initialize_first_chunk(type, ClassType); 3474 } 3475 3476 _alloc_record_head = NULL; 3477 _alloc_record_tail = NULL; 3478 } 3479 3480 size_t Metaspace::align_word_size_up(size_t word_size) { 3481 size_t byte_size = word_size * wordSize; 3482 return ReservedSpace::allocation_align_size_up(byte_size) / wordSize; 3483 } 3484 3485 MetaWord* Metaspace::allocate(size_t word_size, MetadataType mdtype) { 3486 // DumpSharedSpaces doesn't use class metadata area (yet) 3487 // Also, don't use class_vsm() unless UseCompressedClassPointers is true. 3488 if (is_class_space_allocation(mdtype)) { 3489 return class_vsm()->allocate(word_size); 3490 } else { 3491 return vsm()->allocate(word_size); 3492 } 3493 } 3494 3495 MetaWord* Metaspace::expand_and_allocate(size_t word_size, MetadataType mdtype) { 3496 size_t delta_bytes = MetaspaceGC::delta_capacity_until_GC(word_size * BytesPerWord); 3497 assert(delta_bytes > 0, "Must be"); 3498 3499 size_t before = 0; 3500 size_t after = 0; 3501 MetaWord* res; 3502 bool incremented; 3503 3504 // Each thread increments the HWM at most once. Even if the thread fails to increment 3505 // the HWM, an allocation is still attempted. This is because another thread must then 3506 // have incremented the HWM and therefore the allocation might still succeed. 3507 do { 3508 incremented = MetaspaceGC::inc_capacity_until_GC(delta_bytes, &after, &before); 3509 res = allocate(word_size, mdtype); 3510 } while (!incremented && res == NULL); 3511 3512 if (incremented) { 3513 tracer()->report_gc_threshold(before, after, 3514 MetaspaceGCThresholdUpdater::ExpandAndAllocate); 3515 log_trace(gc, metaspace)("Increase capacity to GC from " SIZE_FORMAT " to " SIZE_FORMAT, before, after); 3516 } 3517 3518 return res; 3519 } 3520 3521 // Space allocated in the Metaspace. This may 3522 // be across several metadata virtual spaces. 3523 char* Metaspace::bottom() const { 3524 assert(DumpSharedSpaces, "only useful and valid for dumping shared spaces"); 3525 return (char*)vsm()->current_chunk()->bottom(); 3526 } 3527 3528 size_t Metaspace::used_words_slow(MetadataType mdtype) const { 3529 if (mdtype == ClassType) { 3530 return using_class_space() ? class_vsm()->sum_used_in_chunks_in_use() : 0; 3531 } else { 3532 return vsm()->sum_used_in_chunks_in_use(); // includes overhead! 3533 } 3534 } 3535 3536 size_t Metaspace::free_words_slow(MetadataType mdtype) const { 3537 if (mdtype == ClassType) { 3538 return using_class_space() ? class_vsm()->sum_free_in_chunks_in_use() : 0; 3539 } else { 3540 return vsm()->sum_free_in_chunks_in_use(); 3541 } 3542 } 3543 3544 // Space capacity in the Metaspace. It includes 3545 // space in the list of chunks from which allocations 3546 // have been made. Don't include space in the global freelist and 3547 // in the space available in the dictionary which 3548 // is already counted in some chunk. 3549 size_t Metaspace::capacity_words_slow(MetadataType mdtype) const { 3550 if (mdtype == ClassType) { 3551 return using_class_space() ? class_vsm()->sum_capacity_in_chunks_in_use() : 0; 3552 } else { 3553 return vsm()->sum_capacity_in_chunks_in_use(); 3554 } 3555 } 3556 3557 size_t Metaspace::used_bytes_slow(MetadataType mdtype) const { 3558 return used_words_slow(mdtype) * BytesPerWord; 3559 } 3560 3561 size_t Metaspace::capacity_bytes_slow(MetadataType mdtype) const { 3562 return capacity_words_slow(mdtype) * BytesPerWord; 3563 } 3564 3565 size_t Metaspace::allocated_blocks_bytes() const { 3566 return vsm()->allocated_blocks_bytes() + 3567 (using_class_space() ? class_vsm()->allocated_blocks_bytes() : 0); 3568 } 3569 3570 size_t Metaspace::allocated_chunks_bytes() const { 3571 return vsm()->allocated_chunks_bytes() + 3572 (using_class_space() ? class_vsm()->allocated_chunks_bytes() : 0); 3573 } 3574 3575 void Metaspace::deallocate(MetaWord* ptr, size_t word_size, bool is_class) { 3576 assert(!SafepointSynchronize::is_at_safepoint() 3577 || Thread::current()->is_VM_thread(), "should be the VM thread"); 3578 3579 if (DumpSharedSpaces && log_is_enabled(Info, cds)) { 3580 record_deallocation(ptr, vsm()->get_allocation_word_size(word_size)); 3581 } 3582 3583 MutexLockerEx ml(vsm()->lock(), Mutex::_no_safepoint_check_flag); 3584 3585 if (is_class && using_class_space()) { 3586 class_vsm()->deallocate(ptr, word_size); 3587 } else { 3588 vsm()->deallocate(ptr, word_size); 3589 } 3590 } 3591 3592 3593 MetaWord* Metaspace::allocate(ClassLoaderData* loader_data, size_t word_size, 3594 bool read_only, MetaspaceObj::Type type, TRAPS) { 3595 if (HAS_PENDING_EXCEPTION) { 3596 assert(false, "Should not allocate with exception pending"); 3597 return NULL; // caller does a CHECK_NULL too 3598 } 3599 3600 assert(loader_data != NULL, "Should never pass around a NULL loader_data. " 3601 "ClassLoaderData::the_null_class_loader_data() should have been used."); 3602 3603 // Allocate in metaspaces without taking out a lock, because it deadlocks 3604 // with the SymbolTable_lock. Dumping is single threaded for now. We'll have 3605 // to revisit this for application class data sharing. 3606 if (DumpSharedSpaces) { 3607 assert(type > MetaspaceObj::UnknownType && type < MetaspaceObj::_number_of_types, "sanity"); 3608 Metaspace* space = read_only ? loader_data->ro_metaspace() : loader_data->rw_metaspace(); 3609 MetaWord* result = space->allocate(word_size, NonClassType); 3610 if (result == NULL) { 3611 report_out_of_shared_space(read_only ? SharedReadOnly : SharedReadWrite); 3612 } 3613 if (log_is_enabled(Info, cds)) { 3614 space->record_allocation(result, type, space->vsm()->get_allocation_word_size(word_size)); 3615 } 3616 3617 // Zero initialize. 3618 Copy::fill_to_words((HeapWord*)result, word_size, 0); 3619 3620 return result; 3621 } 3622 3623 MetadataType mdtype = (type == MetaspaceObj::ClassType) ? ClassType : NonClassType; 3624 3625 // Try to allocate metadata. 3626 MetaWord* result = loader_data->metaspace_non_null()->allocate(word_size, mdtype); 3627 3628 if (result == NULL) { 3629 tracer()->report_metaspace_allocation_failure(loader_data, word_size, type, mdtype); 3630 3631 // Allocation failed. 3632 if (is_init_completed()) { 3633 // Only start a GC if the bootstrapping has completed. 3634 3635 // Try to clean out some memory and retry. 3636 result = Universe::heap()->collector_policy()->satisfy_failed_metadata_allocation( 3637 loader_data, word_size, mdtype); 3638 } 3639 } 3640 3641 if (result == NULL) { 3642 SpaceManager* sm; 3643 if (is_class_space_allocation(mdtype)) { 3644 sm = loader_data->metaspace_non_null()->class_vsm(); 3645 } else { 3646 sm = loader_data->metaspace_non_null()->vsm(); 3647 } 3648 3649 result = sm->get_small_chunk_and_allocate(word_size); 3650 3651 if (result == NULL) { 3652 report_metadata_oome(loader_data, word_size, type, mdtype, CHECK_NULL); 3653 } 3654 } 3655 3656 // Zero initialize. 3657 Copy::fill_to_words((HeapWord*)result, word_size, 0); 3658 3659 return result; 3660 } 3661 3662 size_t Metaspace::class_chunk_size(size_t word_size) { 3663 assert(using_class_space(), "Has to use class space"); 3664 return class_vsm()->calc_chunk_size(word_size); 3665 } 3666 3667 void Metaspace::report_metadata_oome(ClassLoaderData* loader_data, size_t word_size, MetaspaceObj::Type type, MetadataType mdtype, TRAPS) { 3668 tracer()->report_metadata_oom(loader_data, word_size, type, mdtype); 3669 3670 // If result is still null, we are out of memory. 3671 Log(gc, metaspace, freelist) log; 3672 if (log.is_info()) { 3673 log.info("Metaspace (%s) allocation failed for size " SIZE_FORMAT, 3674 is_class_space_allocation(mdtype) ? "class" : "data", word_size); 3675 ResourceMark rm; 3676 LogStream ls(log.info()); 3677 if (loader_data->metaspace_or_null() != NULL) { 3678 loader_data->dump(&ls); 3679 } 3680 MetaspaceAux::dump(&ls); 3681 } 3682 3683 bool out_of_compressed_class_space = false; 3684 if (is_class_space_allocation(mdtype)) { 3685 Metaspace* metaspace = loader_data->metaspace_non_null(); 3686 out_of_compressed_class_space = 3687 MetaspaceAux::committed_bytes(Metaspace::ClassType) + 3688 (metaspace->class_chunk_size(word_size) * BytesPerWord) > 3689 CompressedClassSpaceSize; 3690 } 3691 3692 // -XX:+HeapDumpOnOutOfMemoryError and -XX:OnOutOfMemoryError support 3693 const char* space_string = out_of_compressed_class_space ? 3694 "Compressed class space" : "Metaspace"; 3695 3696 report_java_out_of_memory(space_string); 3697 3698 if (JvmtiExport::should_post_resource_exhausted()) { 3699 JvmtiExport::post_resource_exhausted( 3700 JVMTI_RESOURCE_EXHAUSTED_OOM_ERROR, 3701 space_string); 3702 } 3703 3704 if (!is_init_completed()) { 3705 vm_exit_during_initialization("OutOfMemoryError", space_string); 3706 } 3707 3708 if (out_of_compressed_class_space) { 3709 THROW_OOP(Universe::out_of_memory_error_class_metaspace()); 3710 } else { 3711 THROW_OOP(Universe::out_of_memory_error_metaspace()); 3712 } 3713 } 3714 3715 const char* Metaspace::metadata_type_name(Metaspace::MetadataType mdtype) { 3716 switch (mdtype) { 3717 case Metaspace::ClassType: return "Class"; 3718 case Metaspace::NonClassType: return "Metadata"; 3719 default: 3720 assert(false, "Got bad mdtype: %d", (int) mdtype); 3721 return NULL; 3722 } 3723 } 3724 3725 void Metaspace::record_allocation(void* ptr, MetaspaceObj::Type type, size_t word_size) { 3726 assert(DumpSharedSpaces, "sanity"); 3727 3728 int byte_size = (int)word_size * wordSize; 3729 AllocRecord *rec = new AllocRecord((address)ptr, type, byte_size); 3730 3731 if (_alloc_record_head == NULL) { 3732 _alloc_record_head = _alloc_record_tail = rec; 3733 } else if (_alloc_record_tail->_ptr + _alloc_record_tail->_byte_size == (address)ptr) { 3734 _alloc_record_tail->_next = rec; 3735 _alloc_record_tail = rec; 3736 } else { 3737 // slow linear search, but this doesn't happen that often, and only when dumping 3738 for (AllocRecord *old = _alloc_record_head; old; old = old->_next) { 3739 if (old->_ptr == ptr) { 3740 assert(old->_type == MetaspaceObj::DeallocatedType, "sanity"); 3741 int remain_bytes = old->_byte_size - byte_size; 3742 assert(remain_bytes >= 0, "sanity"); 3743 old->_type = type; 3744 3745 if (remain_bytes == 0) { 3746 delete(rec); 3747 } else { 3748 address remain_ptr = address(ptr) + byte_size; 3749 rec->_ptr = remain_ptr; 3750 rec->_byte_size = remain_bytes; 3751 rec->_type = MetaspaceObj::DeallocatedType; 3752 rec->_next = old->_next; 3753 old->_byte_size = byte_size; 3754 old->_next = rec; 3755 } 3756 return; 3757 } 3758 } 3759 assert(0, "reallocating a freed pointer that was not recorded"); 3760 } 3761 } 3762 3763 void Metaspace::record_deallocation(void* ptr, size_t word_size) { 3764 assert(DumpSharedSpaces, "sanity"); 3765 3766 for (AllocRecord *rec = _alloc_record_head; rec; rec = rec->_next) { 3767 if (rec->_ptr == ptr) { 3768 assert(rec->_byte_size == (int)word_size * wordSize, "sanity"); 3769 rec->_type = MetaspaceObj::DeallocatedType; 3770 return; 3771 } 3772 } 3773 3774 assert(0, "deallocating a pointer that was not recorded"); 3775 } 3776 3777 void Metaspace::iterate(Metaspace::AllocRecordClosure *closure) { 3778 assert(DumpSharedSpaces, "unimplemented for !DumpSharedSpaces"); 3779 3780 address last_addr = (address)bottom(); 3781 3782 for (AllocRecord *rec = _alloc_record_head; rec; rec = rec->_next) { 3783 address ptr = rec->_ptr; 3784 if (last_addr < ptr) { 3785 closure->doit(last_addr, MetaspaceObj::UnknownType, ptr - last_addr); 3786 } 3787 closure->doit(ptr, rec->_type, rec->_byte_size); 3788 last_addr = ptr + rec->_byte_size; 3789 } 3790 3791 address top = ((address)bottom()) + used_bytes_slow(Metaspace::NonClassType); 3792 if (last_addr < top) { 3793 closure->doit(last_addr, MetaspaceObj::UnknownType, top - last_addr); 3794 } 3795 } 3796 3797 void Metaspace::purge(MetadataType mdtype) { 3798 get_space_list(mdtype)->purge(get_chunk_manager(mdtype)); 3799 } 3800 3801 void Metaspace::purge() { 3802 MutexLockerEx cl(SpaceManager::expand_lock(), 3803 Mutex::_no_safepoint_check_flag); 3804 purge(NonClassType); 3805 if (using_class_space()) { 3806 purge(ClassType); 3807 } 3808 } 3809 3810 void Metaspace::print_on(outputStream* out) const { 3811 // Print both class virtual space counts and metaspace. 3812 if (Verbose) { 3813 vsm()->print_on(out); 3814 if (using_class_space()) { 3815 class_vsm()->print_on(out); 3816 } 3817 } 3818 } 3819 3820 bool Metaspace::contains(const void* ptr) { 3821 if (UseSharedSpaces && MetaspaceShared::is_in_shared_space(ptr)) { 3822 return true; 3823 } 3824 return contains_non_shared(ptr); 3825 } 3826 3827 bool Metaspace::contains_non_shared(const void* ptr) { 3828 if (using_class_space() && get_space_list(ClassType)->contains(ptr)) { 3829 return true; 3830 } 3831 3832 return get_space_list(NonClassType)->contains(ptr); 3833 } 3834 3835 void Metaspace::verify() { 3836 vsm()->verify(); 3837 if (using_class_space()) { 3838 class_vsm()->verify(); 3839 } 3840 } 3841 3842 void Metaspace::dump(outputStream* const out) const { 3843 out->print_cr("\nVirtual space manager: " INTPTR_FORMAT, p2i(vsm())); 3844 vsm()->dump(out); 3845 if (using_class_space()) { 3846 out->print_cr("\nClass space manager: " INTPTR_FORMAT, p2i(class_vsm())); 3847 class_vsm()->dump(out); 3848 } 3849 } 3850 3851 /////////////// Unit tests /////////////// 3852 3853 #ifndef PRODUCT 3854 3855 class TestMetaspaceAuxTest : AllStatic { 3856 public: 3857 static void test_reserved() { 3858 size_t reserved = MetaspaceAux::reserved_bytes(); 3859 3860 assert(reserved > 0, "assert"); 3861 3862 size_t committed = MetaspaceAux::committed_bytes(); 3863 assert(committed <= reserved, "assert"); 3864 3865 size_t reserved_metadata = MetaspaceAux::reserved_bytes(Metaspace::NonClassType); 3866 assert(reserved_metadata > 0, "assert"); 3867 assert(reserved_metadata <= reserved, "assert"); 3868 3869 if (UseCompressedClassPointers) { 3870 size_t reserved_class = MetaspaceAux::reserved_bytes(Metaspace::ClassType); 3871 assert(reserved_class > 0, "assert"); 3872 assert(reserved_class < reserved, "assert"); 3873 } 3874 } 3875 3876 static void test_committed() { 3877 size_t committed = MetaspaceAux::committed_bytes(); 3878 3879 assert(committed > 0, "assert"); 3880 3881 size_t reserved = MetaspaceAux::reserved_bytes(); 3882 assert(committed <= reserved, "assert"); 3883 3884 size_t committed_metadata = MetaspaceAux::committed_bytes(Metaspace::NonClassType); 3885 assert(committed_metadata > 0, "assert"); 3886 assert(committed_metadata <= committed, "assert"); 3887 3888 if (UseCompressedClassPointers) { 3889 size_t committed_class = MetaspaceAux::committed_bytes(Metaspace::ClassType); 3890 assert(committed_class > 0, "assert"); 3891 assert(committed_class < committed, "assert"); 3892 } 3893 } 3894 3895 static void test_virtual_space_list_large_chunk() { 3896 VirtualSpaceList* vs_list = new VirtualSpaceList(os::vm_allocation_granularity()); 3897 MutexLockerEx cl(SpaceManager::expand_lock(), Mutex::_no_safepoint_check_flag); 3898 // A size larger than VirtualSpaceSize (256k) and add one page to make it _not_ be 3899 // vm_allocation_granularity aligned on Windows. 3900 size_t large_size = (size_t)(2*256*K + (os::vm_page_size()/BytesPerWord)); 3901 large_size += (os::vm_page_size()/BytesPerWord); 3902 vs_list->get_new_chunk(large_size, 0); 3903 } 3904 3905 static void test() { 3906 test_reserved(); 3907 test_committed(); 3908 test_virtual_space_list_large_chunk(); 3909 } 3910 }; 3911 3912 void TestMetaspaceAux_test() { 3913 TestMetaspaceAuxTest::test(); 3914 } 3915 3916 class TestVirtualSpaceNodeTest { 3917 static void chunk_up(size_t words_left, size_t& num_medium_chunks, 3918 size_t& num_small_chunks, 3919 size_t& num_specialized_chunks) { 3920 num_medium_chunks = words_left / MediumChunk; 3921 words_left = words_left % MediumChunk; 3922 3923 num_small_chunks = words_left / SmallChunk; 3924 words_left = words_left % SmallChunk; 3925 // how many specialized chunks can we get? 3926 num_specialized_chunks = words_left / SpecializedChunk; 3927 assert(words_left % SpecializedChunk == 0, "should be nothing left"); 3928 } 3929 3930 public: 3931 static void test() { 3932 MutexLockerEx ml(SpaceManager::expand_lock(), Mutex::_no_safepoint_check_flag); 3933 const size_t vsn_test_size_words = MediumChunk * 4; 3934 const size_t vsn_test_size_bytes = vsn_test_size_words * BytesPerWord; 3935 3936 // The chunk sizes must be multiples of eachother, or this will fail 3937 STATIC_ASSERT(MediumChunk % SmallChunk == 0); 3938 STATIC_ASSERT(SmallChunk % SpecializedChunk == 0); 3939 3940 { // No committed memory in VSN 3941 ChunkManager cm(SpecializedChunk, SmallChunk, MediumChunk); 3942 VirtualSpaceNode vsn(vsn_test_size_bytes); 3943 vsn.initialize(); 3944 vsn.retire(&cm); 3945 assert(cm.sum_free_chunks_count() == 0, "did not commit any memory in the VSN"); 3946 } 3947 3948 { // All of VSN is committed, half is used by chunks 3949 ChunkManager cm(SpecializedChunk, SmallChunk, MediumChunk); 3950 VirtualSpaceNode vsn(vsn_test_size_bytes); 3951 vsn.initialize(); 3952 vsn.expand_by(vsn_test_size_words, vsn_test_size_words); 3953 vsn.get_chunk_vs(MediumChunk); 3954 vsn.get_chunk_vs(MediumChunk); 3955 vsn.retire(&cm); 3956 assert(cm.sum_free_chunks_count() == 2, "should have been memory left for 2 medium chunks"); 3957 assert(cm.sum_free_chunks() == 2*MediumChunk, "sizes should add up"); 3958 } 3959 3960 const size_t page_chunks = 4 * (size_t)os::vm_page_size() / BytesPerWord; 3961 // This doesn't work for systems with vm_page_size >= 16K. 3962 if (page_chunks < MediumChunk) { 3963 // 4 pages of VSN is committed, some is used by chunks 3964 ChunkManager cm(SpecializedChunk, SmallChunk, MediumChunk); 3965 VirtualSpaceNode vsn(vsn_test_size_bytes); 3966 3967 vsn.initialize(); 3968 vsn.expand_by(page_chunks, page_chunks); 3969 vsn.get_chunk_vs(SmallChunk); 3970 vsn.get_chunk_vs(SpecializedChunk); 3971 vsn.retire(&cm); 3972 3973 // committed - used = words left to retire 3974 const size_t words_left = page_chunks - SmallChunk - SpecializedChunk; 3975 3976 size_t num_medium_chunks, num_small_chunks, num_spec_chunks; 3977 chunk_up(words_left, num_medium_chunks, num_small_chunks, num_spec_chunks); 3978 3979 assert(num_medium_chunks == 0, "should not get any medium chunks"); 3980 assert(cm.sum_free_chunks_count() == (num_small_chunks + num_spec_chunks), "should be space for 3 chunks"); 3981 assert(cm.sum_free_chunks() == words_left, "sizes should add up"); 3982 } 3983 3984 { // Half of VSN is committed, a humongous chunk is used 3985 ChunkManager cm(SpecializedChunk, SmallChunk, MediumChunk); 3986 VirtualSpaceNode vsn(vsn_test_size_bytes); 3987 vsn.initialize(); 3988 vsn.expand_by(MediumChunk * 2, MediumChunk * 2); 3989 vsn.get_chunk_vs(MediumChunk + SpecializedChunk); // Humongous chunks will be aligned up to MediumChunk + SpecializedChunk 3990 vsn.retire(&cm); 3991 3992 const size_t words_left = MediumChunk * 2 - (MediumChunk + SpecializedChunk); 3993 size_t num_medium_chunks, num_small_chunks, num_spec_chunks; 3994 chunk_up(words_left, num_medium_chunks, num_small_chunks, num_spec_chunks); 3995 3996 assert(num_medium_chunks == 0, "should not get any medium chunks"); 3997 assert(cm.sum_free_chunks_count() == (num_small_chunks + num_spec_chunks), "should be space for 3 chunks"); 3998 assert(cm.sum_free_chunks() == words_left, "sizes should add up"); 3999 } 4000 4001 } 4002 4003 #define assert_is_available_positive(word_size) \ 4004 assert(vsn.is_available(word_size), \ 4005 #word_size ": " PTR_FORMAT " bytes were not available in " \ 4006 "VirtualSpaceNode [" PTR_FORMAT ", " PTR_FORMAT ")", \ 4007 (uintptr_t)(word_size * BytesPerWord), p2i(vsn.bottom()), p2i(vsn.end())); 4008 4009 #define assert_is_available_negative(word_size) \ 4010 assert(!vsn.is_available(word_size), \ 4011 #word_size ": " PTR_FORMAT " bytes should not be available in " \ 4012 "VirtualSpaceNode [" PTR_FORMAT ", " PTR_FORMAT ")", \ 4013 (uintptr_t)(word_size * BytesPerWord), p2i(vsn.bottom()), p2i(vsn.end())); 4014 4015 static void test_is_available_positive() { 4016 // Reserve some memory. 4017 VirtualSpaceNode vsn(os::vm_allocation_granularity()); 4018 assert(vsn.initialize(), "Failed to setup VirtualSpaceNode"); 4019 4020 // Commit some memory. 4021 size_t commit_word_size = os::vm_allocation_granularity() / BytesPerWord; 4022 bool expanded = vsn.expand_by(commit_word_size, commit_word_size); 4023 assert(expanded, "Failed to commit"); 4024 4025 // Check that is_available accepts the committed size. 4026 assert_is_available_positive(commit_word_size); 4027 4028 // Check that is_available accepts half the committed size. 4029 size_t expand_word_size = commit_word_size / 2; 4030 assert_is_available_positive(expand_word_size); 4031 } 4032 4033 static void test_is_available_negative() { 4034 // Reserve some memory. 4035 VirtualSpaceNode vsn(os::vm_allocation_granularity()); 4036 assert(vsn.initialize(), "Failed to setup VirtualSpaceNode"); 4037 4038 // Commit some memory. 4039 size_t commit_word_size = os::vm_allocation_granularity() / BytesPerWord; 4040 bool expanded = vsn.expand_by(commit_word_size, commit_word_size); 4041 assert(expanded, "Failed to commit"); 4042 4043 // Check that is_available doesn't accept a too large size. 4044 size_t two_times_commit_word_size = commit_word_size * 2; 4045 assert_is_available_negative(two_times_commit_word_size); 4046 } 4047 4048 static void test_is_available_overflow() { 4049 // Reserve some memory. 4050 VirtualSpaceNode vsn(os::vm_allocation_granularity()); 4051 assert(vsn.initialize(), "Failed to setup VirtualSpaceNode"); 4052 4053 // Commit some memory. 4054 size_t commit_word_size = os::vm_allocation_granularity() / BytesPerWord; 4055 bool expanded = vsn.expand_by(commit_word_size, commit_word_size); 4056 assert(expanded, "Failed to commit"); 4057 4058 // Calculate a size that will overflow the virtual space size. 4059 void* virtual_space_max = (void*)(uintptr_t)-1; 4060 size_t bottom_to_max = pointer_delta(virtual_space_max, vsn.bottom(), 1); 4061 size_t overflow_size = bottom_to_max + BytesPerWord; 4062 size_t overflow_word_size = overflow_size / BytesPerWord; 4063 4064 // Check that is_available can handle the overflow. 4065 assert_is_available_negative(overflow_word_size); 4066 } 4067 4068 static void test_is_available() { 4069 TestVirtualSpaceNodeTest::test_is_available_positive(); 4070 TestVirtualSpaceNodeTest::test_is_available_negative(); 4071 TestVirtualSpaceNodeTest::test_is_available_overflow(); 4072 } 4073 }; 4074 4075 void TestVirtualSpaceNode_test() { 4076 TestVirtualSpaceNodeTest::test(); 4077 TestVirtualSpaceNodeTest::test_is_available(); 4078 } 4079 4080 // The following test is placed here instead of a gtest / unittest file 4081 // because the ChunkManager class is only available in this file. 4082 void ChunkManager_test_list_index() { 4083 ChunkManager manager(ClassSpecializedChunk, ClassSmallChunk, ClassMediumChunk); 4084 4085 // Test previous bug where a query for a humongous class metachunk, 4086 // incorrectly matched the non-class medium metachunk size. 4087 { 4088 assert(MediumChunk > ClassMediumChunk, "Precondition for test"); 4089 4090 ChunkIndex index = manager.list_index(MediumChunk); 4091 4092 assert(index == HumongousIndex, 4093 "Requested size is larger than ClassMediumChunk," 4094 " so should return HumongousIndex. Got index: %d", (int)index); 4095 } 4096 4097 // Check the specified sizes as well. 4098 { 4099 ChunkIndex index = manager.list_index(ClassSpecializedChunk); 4100 assert(index == SpecializedIndex, "Wrong index returned. Got index: %d", (int)index); 4101 } 4102 { 4103 ChunkIndex index = manager.list_index(ClassSmallChunk); 4104 assert(index == SmallIndex, "Wrong index returned. Got index: %d", (int)index); 4105 } 4106 { 4107 ChunkIndex index = manager.list_index(ClassMediumChunk); 4108 assert(index == MediumIndex, "Wrong index returned. Got index: %d", (int)index); 4109 } 4110 { 4111 ChunkIndex index = manager.list_index(ClassMediumChunk + 1); 4112 assert(index == HumongousIndex, "Wrong index returned. Got index: %d", (int)index); 4113 } 4114 } 4115 4116 // ChunkManagerReturnTest stresses taking/returning chunks from the ChunkManager. It takes and 4117 // returns chunks from/to the ChunkManager while keeping track of the expected ChunkManager 4118 // content. 4119 class ChunkManagerReturnTestImpl { 4120 4121 VirtualSpaceNode _vsn; 4122 ChunkManager _cm; 4123 4124 // The expected content of the chunk manager. 4125 unsigned _chunks_in_chunkmanager; 4126 size_t _words_in_chunkmanager; 4127 4128 // A fixed size pool of chunks. Chunks may be in the chunk manager (free) or not (in use). 4129 static const int num_chunks = 256; 4130 Metachunk* _pool[num_chunks]; 4131 4132 // Helper, return a random position into the chunk pool. 4133 static int get_random_position() { 4134 return os::random() % num_chunks; 4135 } 4136 4137 // Asserts that ChunkManager counters match expectations. 4138 void assert_counters() { 4139 assert(_vsn.container_count() == num_chunks - _chunks_in_chunkmanager, "vsn counter mismatch."); 4140 assert(_cm.free_chunks_count() == _chunks_in_chunkmanager, "cm counter mismatch."); 4141 assert(_cm.free_chunks_total_words() == _words_in_chunkmanager, "cm counter mismatch."); 4142 } 4143 4144 // Get a random chunk size. Equal chance to get spec/med/small chunk size or 4145 // a humongous chunk size. The latter itself is random in the range of [med+spec..4*med). 4146 size_t get_random_chunk_size() { 4147 const size_t sizes [] = { SpecializedChunk, SmallChunk, MediumChunk }; 4148 const int rand = os::random() % 4; 4149 if (rand < 3) { 4150 return sizes[rand]; 4151 } else { 4152 // Note: this affects the max. size of space (see _vsn initialization in ctor). 4153 return align_size_up(MediumChunk + 1 + (os::random() % (MediumChunk * 4)), SpecializedChunk); 4154 } 4155 } 4156 4157 // Starting at pool index <start>+1, find the next chunk tagged as either free or in use, depending 4158 // on <is_free>. Search wraps. Returns its position, or -1 if no matching chunk was found. 4159 int next_matching_chunk(int start, bool is_free) const { 4160 assert(start >= 0 && start < num_chunks, "invalid parameter"); 4161 int pos = start; 4162 do { 4163 if (++pos == num_chunks) { 4164 pos = 0; 4165 } 4166 if (_pool[pos]->is_tagged_free() == is_free) { 4167 return pos; 4168 } 4169 } while (pos != start); 4170 return -1; 4171 } 4172 4173 // A structure to keep information about a chunk list including which 4174 // chunks are part of this list. This is needed to keep information about a chunk list 4175 // we will to return to the ChunkManager, because the original list will be destroyed. 4176 struct AChunkList { 4177 Metachunk* head; 4178 Metachunk* all[num_chunks]; 4179 size_t size; 4180 int num; 4181 ChunkIndex index; 4182 }; 4183 4184 // Assemble, from the in-use chunks (not in the chunk manager) in the pool, 4185 // a random chunk list of max. length <list_size> of chunks with the same 4186 // ChunkIndex (chunk size). 4187 // Returns false if list cannot be assembled. List is returned in the <out> 4188 // structure. Returned list may be smaller than <list_size>. 4189 bool assemble_random_chunklist(AChunkList* out, int list_size) { 4190 // Choose a random in-use chunk from the pool... 4191 const int headpos = next_matching_chunk(get_random_position(), false); 4192 if (headpos == -1) { 4193 return false; 4194 } 4195 Metachunk* const head = _pool[headpos]; 4196 out->all[0] = head; 4197 assert(head->is_tagged_free() == false, "Chunk state mismatch"); 4198 // ..then go from there, chain it up with up to list_size - 1 number of other 4199 // in-use chunks of the same index. 4200 const ChunkIndex index = _cm.list_index(head->word_size()); 4201 int num_added = 1; 4202 size_t size_added = head->word_size(); 4203 int pos = headpos; 4204 Metachunk* tail = head; 4205 do { 4206 pos = next_matching_chunk(pos, false); 4207 if (pos != headpos) { 4208 Metachunk* c = _pool[pos]; 4209 assert(c->is_tagged_free() == false, "Chunk state mismatch"); 4210 if (index == _cm.list_index(c->word_size())) { 4211 tail->set_next(c); 4212 c->set_prev(tail); 4213 tail = c; 4214 out->all[num_added] = c; 4215 num_added ++; 4216 size_added += c->word_size(); 4217 } 4218 } 4219 } while (num_added < list_size && pos != headpos); 4220 out->head = head; 4221 out->index = index; 4222 out->size = size_added; 4223 out->num = num_added; 4224 return true; 4225 } 4226 4227 // Take a single random chunk from the ChunkManager. 4228 bool take_single_random_chunk_from_chunkmanager() { 4229 assert_counters(); 4230 _cm.locked_verify(); 4231 int pos = next_matching_chunk(get_random_position(), true); 4232 if (pos == -1) { 4233 return false; 4234 } 4235 Metachunk* c = _pool[pos]; 4236 assert(c->is_tagged_free(), "Chunk state mismatch"); 4237 // Note: instead of using ChunkManager::remove_chunk on this one chunk, we call 4238 // ChunkManager::free_chunks_get() with this chunk's word size. We really want 4239 // to exercise ChunkManager::free_chunks_get() because that one gets called for 4240 // normal chunk allocation. 4241 Metachunk* c2 = _cm.free_chunks_get(c->word_size()); 4242 assert(c2 != NULL, "Unexpected."); 4243 assert(!c2->is_tagged_free(), "Chunk state mismatch"); 4244 assert(c2->next() == NULL && c2->prev() == NULL, "Chunk should be outside of a list."); 4245 _chunks_in_chunkmanager --; 4246 _words_in_chunkmanager -= c->word_size(); 4247 assert_counters(); 4248 _cm.locked_verify(); 4249 return true; 4250 } 4251 4252 // Returns a single random chunk to the chunk manager. Returns false if that 4253 // was not possible (all chunks are already in the chunk manager). 4254 bool return_single_random_chunk_to_chunkmanager() { 4255 assert_counters(); 4256 _cm.locked_verify(); 4257 int pos = next_matching_chunk(get_random_position(), false); 4258 if (pos == -1) { 4259 return false; 4260 } 4261 Metachunk* c = _pool[pos]; 4262 assert(c->is_tagged_free() == false, "wrong chunk information"); 4263 _cm.return_single_chunk(_cm.list_index(c->word_size()), c); 4264 _chunks_in_chunkmanager ++; 4265 _words_in_chunkmanager += c->word_size(); 4266 assert(c->is_tagged_free() == true, "wrong chunk information"); 4267 assert_counters(); 4268 _cm.locked_verify(); 4269 return true; 4270 } 4271 4272 // Return a random chunk list to the chunk manager. Returns the length of the 4273 // returned list. 4274 int return_random_chunk_list_to_chunkmanager(int list_size) { 4275 assert_counters(); 4276 _cm.locked_verify(); 4277 AChunkList aChunkList; 4278 if (!assemble_random_chunklist(&aChunkList, list_size)) { 4279 return 0; 4280 } 4281 // Before returning chunks are returned, they should be tagged in use. 4282 for (int i = 0; i < aChunkList.num; i ++) { 4283 assert(!aChunkList.all[i]->is_tagged_free(), "chunk state mismatch."); 4284 } 4285 _cm.return_chunk_list(aChunkList.index, aChunkList.head); 4286 _chunks_in_chunkmanager += aChunkList.num; 4287 _words_in_chunkmanager += aChunkList.size; 4288 // After all chunks are returned, check that they are now tagged free. 4289 for (int i = 0; i < aChunkList.num; i ++) { 4290 assert(aChunkList.all[i]->is_tagged_free(), "chunk state mismatch."); 4291 } 4292 assert_counters(); 4293 _cm.locked_verify(); 4294 return aChunkList.num; 4295 } 4296 4297 public: 4298 4299 ChunkManagerReturnTestImpl() 4300 : _vsn(align_size_up(MediumChunk * num_chunks * 5 * sizeof(MetaWord), Metaspace::reserve_alignment())) 4301 , _cm(SpecializedChunk, SmallChunk, MediumChunk) 4302 , _chunks_in_chunkmanager(0) 4303 , _words_in_chunkmanager(0) 4304 { 4305 MutexLockerEx ml(SpaceManager::expand_lock(), Mutex::_no_safepoint_check_flag); 4306 // Allocate virtual space and allocate random chunks. Keep these chunks in the _pool. These chunks are 4307 // "in use", because not yet added to any chunk manager. 4308 _vsn.initialize(); 4309 _vsn.expand_by(_vsn.reserved_words(), _vsn.reserved_words()); 4310 for (int i = 0; i < num_chunks; i ++) { 4311 const size_t size = get_random_chunk_size(); 4312 _pool[i] = _vsn.get_chunk_vs(size); 4313 assert(_pool[i] != NULL, "allocation failed"); 4314 } 4315 assert_counters(); 4316 _cm.locked_verify(); 4317 } 4318 4319 // Test entry point. 4320 // Return some chunks to the chunk manager (return phase). Take some chunks out (take phase). Repeat. 4321 // Chunks are choosen randomly. Number of chunks to return or taken are choosen randomly, but affected 4322 // by the <phase_length_factor> argument: a factor of 0.0 will cause the test to quickly alternate between 4323 // returning and taking, whereas a factor of 1.0 will take/return all chunks from/to the 4324 // chunks manager, thereby emptying or filling it completely. 4325 void do_test(float phase_length_factor) { 4326 MutexLockerEx ml(SpaceManager::expand_lock(), Mutex::_no_safepoint_check_flag); 4327 assert_counters(); 4328 // Execute n operations, and operation being the move of a single chunk to/from the chunk manager. 4329 const int num_max_ops = num_chunks * 100; 4330 int num_ops = num_max_ops; 4331 const int average_phase_length = (int)(phase_length_factor * num_chunks); 4332 int num_ops_until_switch = MAX2(1, (int)(average_phase_length + os::random() % 8 - 4)); 4333 bool return_phase = true; 4334 while (num_ops > 0) { 4335 int chunks_moved = 0; 4336 if (return_phase) { 4337 // Randomly switch between returning a single chunk or a random length chunk list. 4338 if (os::random() % 2 == 0) { 4339 if (return_single_random_chunk_to_chunkmanager()) { 4340 chunks_moved = 1; 4341 } 4342 } else { 4343 const int list_length = MAX2(1, (int)(os::random() % num_ops_until_switch)); 4344 chunks_moved = return_random_chunk_list_to_chunkmanager(list_length); 4345 } 4346 } else { 4347 // Breath out. 4348 if (take_single_random_chunk_from_chunkmanager()) { 4349 chunks_moved = 1; 4350 } 4351 } 4352 num_ops -= chunks_moved; 4353 num_ops_until_switch -= chunks_moved; 4354 if (chunks_moved == 0 || num_ops_until_switch <= 0) { 4355 return_phase = !return_phase; 4356 num_ops_until_switch = MAX2(1, (int)(average_phase_length + os::random() % 8 - 4)); 4357 } 4358 } 4359 } 4360 }; 4361 4362 void* setup_chunkmanager_returntests() { 4363 ChunkManagerReturnTestImpl* p = new ChunkManagerReturnTestImpl(); 4364 return p; 4365 } 4366 4367 void teardown_chunkmanager_returntests(void* p) { 4368 delete (ChunkManagerReturnTestImpl*) p; 4369 } 4370 4371 void run_chunkmanager_returntests(void* p, float phase_length) { 4372 ChunkManagerReturnTestImpl* test = (ChunkManagerReturnTestImpl*) p; 4373 test->do_test(phase_length); 4374 } 4375 4376 // The following test is placed here instead of a gtest / unittest file 4377 // because the ChunkManager class is only available in this file. 4378 class SpaceManagerTest : AllStatic { 4379 friend void SpaceManager_test_adjust_initial_chunk_size(); 4380 4381 static void test_adjust_initial_chunk_size(bool is_class) { 4382 const size_t smallest = SpaceManager::smallest_chunk_size(is_class); 4383 const size_t normal = SpaceManager::small_chunk_size(is_class); 4384 const size_t medium = SpaceManager::medium_chunk_size(is_class); 4385 4386 #define test_adjust_initial_chunk_size(value, expected, is_class_value) \ 4387 do { \ 4388 size_t v = value; \ 4389 size_t e = expected; \ 4390 assert(SpaceManager::adjust_initial_chunk_size(v, (is_class_value)) == e, \ 4391 "Expected: " SIZE_FORMAT " got: " SIZE_FORMAT, e, v); \ 4392 } while (0) 4393 4394 // Smallest (specialized) 4395 test_adjust_initial_chunk_size(1, smallest, is_class); 4396 test_adjust_initial_chunk_size(smallest - 1, smallest, is_class); 4397 test_adjust_initial_chunk_size(smallest, smallest, is_class); 4398 4399 // Small 4400 test_adjust_initial_chunk_size(smallest + 1, normal, is_class); 4401 test_adjust_initial_chunk_size(normal - 1, normal, is_class); 4402 test_adjust_initial_chunk_size(normal, normal, is_class); 4403 4404 // Medium 4405 test_adjust_initial_chunk_size(normal + 1, medium, is_class); 4406 test_adjust_initial_chunk_size(medium - 1, medium, is_class); 4407 test_adjust_initial_chunk_size(medium, medium, is_class); 4408 4409 // Humongous 4410 test_adjust_initial_chunk_size(medium + 1, medium + 1, is_class); 4411 4412 #undef test_adjust_initial_chunk_size 4413 } 4414 4415 static void test_adjust_initial_chunk_size() { 4416 test_adjust_initial_chunk_size(false); 4417 test_adjust_initial_chunk_size(true); 4418 } 4419 }; 4420 4421 void SpaceManager_test_adjust_initial_chunk_size() { 4422 SpaceManagerTest::test_adjust_initial_chunk_size(); 4423 } 4424 4425 #endif