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