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