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