1 /*
2 * Copyright (c) 2011, 2017, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24 #include "precompiled.hpp"
25 #include "aot/aotLoader.hpp"
26 #include "gc/shared/collectedHeap.hpp"
27 #include "gc/shared/collectorPolicy.hpp"
28 #include "gc/shared/gcLocker.hpp"
29 #include "logging/log.hpp"
30 #include "memory/allocation.hpp"
31 #include "memory/binaryTreeDictionary.hpp"
32 #include "memory/filemap.hpp"
33 #include "memory/freeList.hpp"
34 #include "memory/metachunk.hpp"
35 #include "memory/metaspace.hpp"
36 #include "memory/metaspaceGCThresholdUpdater.hpp"
37 #include "memory/metaspaceShared.hpp"
38 #include "memory/metaspaceTracer.hpp"
39 #include "memory/resourceArea.hpp"
40 #include "memory/universe.hpp"
41 #include "runtime/atomic.hpp"
42 #include "runtime/globals.hpp"
43 #include "runtime/init.hpp"
44 #include "runtime/java.hpp"
45 #include "runtime/mutex.hpp"
46 #include "runtime/orderAccess.inline.hpp"
47 #include "services/memTracker.hpp"
48 #include "services/memoryService.hpp"
49 #include "utilities/copy.hpp"
50 #include "utilities/debug.hpp"
51 #include "utilities/macros.hpp"
52
53 typedef BinaryTreeDictionary<Metablock, FreeList<Metablock> > BlockTreeDictionary;
54 typedef BinaryTreeDictionary<Metachunk, FreeList<Metachunk> > ChunkTreeDictionary;
55
56 // Set this constant to enable slow integrity checking of the free chunk lists
57 const bool metaspace_slow_verify = false;
58
59 size_t const allocation_from_dictionary_limit = 4 * K;
60
61 MetaWord* last_allocated = 0;
62
63 size_t Metaspace::_compressed_class_space_size;
64 const MetaspaceTracer* Metaspace::_tracer = NULL;
65
66 // Used in declarations in SpaceManager and ChunkManager
67 enum ChunkIndex {
68 ZeroIndex = 0,
69 SpecializedIndex = ZeroIndex,
70 SmallIndex = SpecializedIndex + 1,
71 MediumIndex = SmallIndex + 1,
72 HumongousIndex = MediumIndex + 1,
73 NumberOfFreeLists = 3,
74 NumberOfInUseLists = 4
75 };
76
77 // Helper, returns a descriptive name for the given index.
78 static const char* chunk_size_name(ChunkIndex index) {
79 switch (index) {
80 case SpecializedIndex:
81 return "specialized";
82 case SmallIndex:
83 return "small";
84 case MediumIndex:
85 return "medium";
86 case HumongousIndex:
87 return "humongous";
88 default:
89 return "Invalid index";
90 }
91 }
92
93 enum ChunkSizes { // in words.
94 ClassSpecializedChunk = 128,
95 SpecializedChunk = 128,
96 ClassSmallChunk = 256,
97 SmallChunk = 512,
98 ClassMediumChunk = 4 * K,
99 MediumChunk = 8 * K
100 };
101
102 static ChunkIndex next_chunk_index(ChunkIndex i) {
103 assert(i < NumberOfInUseLists, "Out of bound");
104 return (ChunkIndex) (i+1);
105 }
106
107 volatile intptr_t MetaspaceGC::_capacity_until_GC = 0;
108 uint MetaspaceGC::_shrink_factor = 0;
109 bool MetaspaceGC::_should_concurrent_collect = false;
110
111 typedef class FreeList<Metachunk> ChunkList;
112
113 // Manages the global free lists of chunks.
114 class ChunkManager : public CHeapObj<mtInternal> {
115 friend class TestVirtualSpaceNodeTest;
116
117 // Free list of chunks of different sizes.
118 // SpecializedChunk
119 // SmallChunk
120 // MediumChunk
121 ChunkList _free_chunks[NumberOfFreeLists];
122
123 // Return non-humongous chunk list by its index.
124 ChunkList* free_chunks(ChunkIndex index);
125
126 // Returns non-humongous chunk list for the given chunk word size.
127 ChunkList* find_free_chunks_list(size_t word_size);
128
129 // HumongousChunk
130 ChunkTreeDictionary _humongous_dictionary;
131
132 // Returns the humongous chunk dictionary.
133 ChunkTreeDictionary* humongous_dictionary() {
134 return &_humongous_dictionary;
135 }
136
137 // Size, in metaspace words, of all chunks managed by this ChunkManager
138 size_t _free_chunks_total;
139 // Number of chunks in this ChunkManager
140 size_t _free_chunks_count;
141
142 // Update counters after a chunk was added or removed removed.
143 void account_for_added_chunk(const Metachunk* c);
144 void account_for_removed_chunk(const Metachunk* c);
145
146 // Debug support
147
148 size_t sum_free_chunks();
149 size_t sum_free_chunks_count();
150
151 void locked_verify_free_chunks_total();
152 void slow_locked_verify_free_chunks_total() {
153 if (metaspace_slow_verify) {
154 locked_verify_free_chunks_total();
155 }
156 }
157 void locked_verify_free_chunks_count();
158 void slow_locked_verify_free_chunks_count() {
159 if (metaspace_slow_verify) {
160 locked_verify_free_chunks_count();
161 }
162 }
163 void verify_free_chunks_count();
164
165 public:
166
167 ChunkManager(size_t specialized_size, size_t small_size, size_t medium_size)
168 : _free_chunks_total(0), _free_chunks_count(0) {
169 _free_chunks[SpecializedIndex].set_size(specialized_size);
170 _free_chunks[SmallIndex].set_size(small_size);
171 _free_chunks[MediumIndex].set_size(medium_size);
172 }
173
174 // add or delete (return) a chunk to the global freelist.
175 Metachunk* chunk_freelist_allocate(size_t word_size);
176
177 // Map a size to a list index assuming that there are lists
178 // for special, small, medium, and humongous chunks.
179 ChunkIndex list_index(size_t size);
180
181 // Map a given index to the chunk size.
182 size_t size_by_index(ChunkIndex index);
183
184 // Take a chunk from the ChunkManager. The chunk is expected to be in
185 // the chunk manager (the freelist if non-humongous, the dictionary if
186 // humongous).
187 void remove_chunk(Metachunk* chunk);
188
189 // Return a single chunk of type index to the ChunkManager.
190 void return_single_chunk(ChunkIndex index, Metachunk* chunk);
191
192 // Add the simple linked list of chunks to the freelist of chunks
193 // of type index.
194 void return_chunk_list(ChunkIndex index, Metachunk* chunk);
195
196 // Total of the space in the free chunks list
197 size_t free_chunks_total_words();
198 size_t free_chunks_total_bytes();
199
200 // Number of chunks in the free chunks list
201 size_t free_chunks_count();
202
203 // Remove from a list by size. Selects list based on size of chunk.
204 Metachunk* free_chunks_get(size_t chunk_word_size);
205
206 #define index_bounds_check(index) \
207 assert(index == SpecializedIndex || \
208 index == SmallIndex || \
209 index == MediumIndex || \
210 index == HumongousIndex, "Bad index: %d", (int) index)
211
212 size_t num_free_chunks(ChunkIndex index) const {
213 index_bounds_check(index);
214
215 if (index == HumongousIndex) {
216 return _humongous_dictionary.total_free_blocks();
217 }
218
219 ssize_t count = _free_chunks[index].count();
220 return count == -1 ? 0 : (size_t) count;
221 }
222
223 size_t size_free_chunks_in_bytes(ChunkIndex index) const {
224 index_bounds_check(index);
225
226 size_t word_size = 0;
227 if (index == HumongousIndex) {
228 word_size = _humongous_dictionary.total_size();
229 } else {
230 const size_t size_per_chunk_in_words = _free_chunks[index].size();
231 word_size = size_per_chunk_in_words * num_free_chunks(index);
232 }
233
234 return word_size * BytesPerWord;
235 }
236
237 MetaspaceChunkFreeListSummary chunk_free_list_summary() const {
238 return MetaspaceChunkFreeListSummary(num_free_chunks(SpecializedIndex),
239 num_free_chunks(SmallIndex),
240 num_free_chunks(MediumIndex),
241 num_free_chunks(HumongousIndex),
242 size_free_chunks_in_bytes(SpecializedIndex),
243 size_free_chunks_in_bytes(SmallIndex),
244 size_free_chunks_in_bytes(MediumIndex),
245 size_free_chunks_in_bytes(HumongousIndex));
246 }
247
248 // Debug support
249 void verify();
250 void slow_verify() {
251 if (metaspace_slow_verify) {
252 verify();
253 }
254 }
255 void locked_verify();
256 void slow_locked_verify() {
257 if (metaspace_slow_verify) {
258 locked_verify();
259 }
260 }
261 void verify_free_chunks_total();
262
263 void locked_print_free_chunks(outputStream* st);
264 void locked_print_sum_free_chunks(outputStream* st);
265
266 void print_on(outputStream* st) const;
267 };
268
269 class SmallBlocks : public CHeapObj<mtClass> {
270 const static uint _small_block_max_size = sizeof(TreeChunk<Metablock, FreeList<Metablock> >)/HeapWordSize;
271 const static uint _small_block_min_size = sizeof(Metablock)/HeapWordSize;
272
273 private:
274 FreeList<Metablock> _small_lists[_small_block_max_size - _small_block_min_size];
275
276 FreeList<Metablock>& list_at(size_t word_size) {
277 assert(word_size >= _small_block_min_size, "There are no metaspace objects less than %u words", _small_block_min_size);
278 return _small_lists[word_size - _small_block_min_size];
279 }
280
281 public:
282 SmallBlocks() {
283 for (uint i = _small_block_min_size; i < _small_block_max_size; i++) {
284 uint k = i - _small_block_min_size;
285 _small_lists[k].set_size(i);
286 }
287 }
288
289 size_t total_size() const {
290 size_t result = 0;
291 for (uint i = _small_block_min_size; i < _small_block_max_size; i++) {
292 uint k = i - _small_block_min_size;
293 result = result + _small_lists[k].count() * _small_lists[k].size();
294 }
295 return result;
296 }
297
298 static uint small_block_max_size() { return _small_block_max_size; }
299 static uint small_block_min_size() { return _small_block_min_size; }
300
301 MetaWord* get_block(size_t word_size) {
302 if (list_at(word_size).count() > 0) {
303 MetaWord* new_block = (MetaWord*) list_at(word_size).get_chunk_at_head();
304 return new_block;
305 } else {
306 return NULL;
307 }
308 }
309 void return_block(Metablock* free_chunk, size_t word_size) {
310 list_at(word_size).return_chunk_at_head(free_chunk, false);
311 assert(list_at(word_size).count() > 0, "Should have a chunk");
312 }
313
314 void print_on(outputStream* st) const {
315 st->print_cr("SmallBlocks:");
316 for (uint i = _small_block_min_size; i < _small_block_max_size; i++) {
317 uint k = i - _small_block_min_size;
318 st->print_cr("small_lists size " SIZE_FORMAT " count " SIZE_FORMAT, _small_lists[k].size(), _small_lists[k].count());
319 }
320 }
321 };
322
323 // Used to manage the free list of Metablocks (a block corresponds
324 // to the allocation of a quantum of metadata).
325 class BlockFreelist : public CHeapObj<mtClass> {
326 BlockTreeDictionary* const _dictionary;
327 SmallBlocks* _small_blocks;
328
329 // Only allocate and split from freelist if the size of the allocation
330 // is at least 1/4th the size of the available block.
331 const static int WasteMultiplier = 4;
332
333 // Accessors
334 BlockTreeDictionary* dictionary() const { return _dictionary; }
335 SmallBlocks* small_blocks() {
336 if (_small_blocks == NULL) {
337 _small_blocks = new SmallBlocks();
338 }
339 return _small_blocks;
340 }
341
342 public:
343 BlockFreelist();
344 ~BlockFreelist();
345
346 // Get and return a block to the free list
347 MetaWord* get_block(size_t word_size);
348 void return_block(MetaWord* p, size_t word_size);
349
350 size_t total_size() const {
351 size_t result = dictionary()->total_size();
352 if (_small_blocks != NULL) {
353 result = result + _small_blocks->total_size();
354 }
355 return result;
356 }
357
358 static size_t min_dictionary_size() { return TreeChunk<Metablock, FreeList<Metablock> >::min_size(); }
359 void print_on(outputStream* st) const;
360 };
361
362 // A VirtualSpaceList node.
363 class VirtualSpaceNode : public CHeapObj<mtClass> {
364 friend class VirtualSpaceList;
365
366 // Link to next VirtualSpaceNode
367 VirtualSpaceNode* _next;
368
369 // total in the VirtualSpace
370 MemRegion _reserved;
371 ReservedSpace _rs;
372 VirtualSpace _virtual_space;
373 MetaWord* _top;
374 // count of chunks contained in this VirtualSpace
375 uintx _container_count;
376
377 // Convenience functions to access the _virtual_space
378 char* low() const { return virtual_space()->low(); }
379 char* high() const { return virtual_space()->high(); }
380
381 // The first Metachunk will be allocated at the bottom of the
382 // VirtualSpace
383 Metachunk* first_chunk() { return (Metachunk*) bottom(); }
384
385 // Committed but unused space in the virtual space
386 size_t free_words_in_vs() const;
387 public:
388
389 VirtualSpaceNode(size_t byte_size);
390 VirtualSpaceNode(ReservedSpace rs) : _top(NULL), _next(NULL), _rs(rs), _container_count(0) {}
391 ~VirtualSpaceNode();
392
393 // Convenience functions for logical bottom and end
394 MetaWord* bottom() const { return (MetaWord*) _virtual_space.low(); }
395 MetaWord* end() const { return (MetaWord*) _virtual_space.high(); }
396
397 bool contains(const void* ptr) { return ptr >= low() && ptr < high(); }
398
399 size_t reserved_words() const { return _virtual_space.reserved_size() / BytesPerWord; }
400 size_t committed_words() const { return _virtual_space.actual_committed_size() / BytesPerWord; }
401
402 bool is_pre_committed() const { return _virtual_space.special(); }
403
404 // address of next available space in _virtual_space;
405 // Accessors
406 VirtualSpaceNode* next() { return _next; }
407 void set_next(VirtualSpaceNode* v) { _next = v; }
408
409 void set_reserved(MemRegion const v) { _reserved = v; }
410 void set_top(MetaWord* v) { _top = v; }
411
412 // Accessors
413 MemRegion* reserved() { return &_reserved; }
414 VirtualSpace* virtual_space() const { return (VirtualSpace*) &_virtual_space; }
415
416 // Returns true if "word_size" is available in the VirtualSpace
417 bool is_available(size_t word_size) { return word_size <= pointer_delta(end(), _top, sizeof(MetaWord)); }
418
419 MetaWord* top() const { return _top; }
420 void inc_top(size_t word_size) { _top += word_size; }
421
422 uintx container_count() { return _container_count; }
423 void inc_container_count();
424 void dec_container_count();
425 #ifdef ASSERT
426 uintx container_count_slow();
427 void verify_container_count();
428 #endif
429
430 // used and capacity in this single entry in the list
431 size_t used_words_in_vs() const;
432 size_t capacity_words_in_vs() const;
433
434 bool initialize();
435
436 // get space from the virtual space
437 Metachunk* take_from_committed(size_t chunk_word_size);
438
439 // Allocate a chunk from the virtual space and return it.
440 Metachunk* get_chunk_vs(size_t chunk_word_size);
441
442 // Expands/shrinks the committed space in a virtual space. Delegates
443 // to Virtualspace
444 bool expand_by(size_t min_words, size_t preferred_words);
445
446 // In preparation for deleting this node, remove all the chunks
447 // in the node from any freelist.
448 void purge(ChunkManager* chunk_manager);
449
450 // If an allocation doesn't fit in the current node a new node is created.
451 // Allocate chunks out of the remaining committed space in this node
452 // to avoid wasting that memory.
453 // This always adds up because all the chunk sizes are multiples of
454 // the smallest chunk size.
455 void retire(ChunkManager* chunk_manager);
456
457 #ifdef ASSERT
458 // Debug support
459 void mangle();
460 #endif
461
462 void print_on(outputStream* st) const;
463 };
464
465 #define assert_is_aligned(value, alignment) \
466 assert(is_aligned((value), (alignment)), \
467 SIZE_FORMAT_HEX " is not aligned to " \
468 SIZE_FORMAT, (size_t)(uintptr_t)value, (alignment))
469
470 // Decide if large pages should be committed when the memory is reserved.
471 static bool should_commit_large_pages_when_reserving(size_t bytes) {
472 if (UseLargePages && UseLargePagesInMetaspace && !os::can_commit_large_page_memory()) {
473 size_t words = bytes / BytesPerWord;
474 bool is_class = false; // We never reserve large pages for the class space.
475 if (MetaspaceGC::can_expand(words, is_class) &&
476 MetaspaceGC::allowed_expansion() >= words) {
477 return true;
478 }
479 }
480
481 return false;
482 }
483
484 // byte_size is the size of the associated virtualspace.
485 VirtualSpaceNode::VirtualSpaceNode(size_t bytes) : _top(NULL), _next(NULL), _rs(), _container_count(0) {
486 assert_is_aligned(bytes, Metaspace::reserve_alignment());
487
488 #if INCLUDE_CDS
489 // This allocates memory with mmap. For DumpSharedspaces, try to reserve
490 // configurable address, generally at the top of the Java heap so other
491 // memory addresses don't conflict.
492 if (DumpSharedSpaces) {
493 bool large_pages = false; // No large pages when dumping the CDS archive.
494 char* shared_base = align_up((char*)SharedBaseAddress, Metaspace::reserve_alignment());
495
496 _rs = ReservedSpace(bytes, Metaspace::reserve_alignment(), large_pages, shared_base);
497 if (_rs.is_reserved()) {
498 assert(shared_base == 0 || _rs.base() == shared_base, "should match");
499 } else {
500 // Get a mmap region anywhere if the SharedBaseAddress fails.
501 _rs = ReservedSpace(bytes, Metaspace::reserve_alignment(), large_pages);
502 }
503 if (!_rs.is_reserved()) {
504 vm_exit_during_initialization("Unable to allocate memory for shared space",
505 err_msg(SIZE_FORMAT " bytes.", bytes));
506 }
507 MetaspaceShared::initialize_shared_rs(&_rs);
508 } else
509 #endif
510 {
511 bool large_pages = should_commit_large_pages_when_reserving(bytes);
512
513 _rs = ReservedSpace(bytes, Metaspace::reserve_alignment(), large_pages);
514 }
515
516 if (_rs.is_reserved()) {
517 assert(_rs.base() != NULL, "Catch if we get a NULL address");
518 assert(_rs.size() != 0, "Catch if we get a 0 size");
519 assert_is_aligned(_rs.base(), Metaspace::reserve_alignment());
520 assert_is_aligned(_rs.size(), Metaspace::reserve_alignment());
521
522 MemTracker::record_virtual_memory_type((address)_rs.base(), mtClass);
523 }
524 }
525
526 void VirtualSpaceNode::purge(ChunkManager* chunk_manager) {
527 Metachunk* chunk = first_chunk();
528 Metachunk* invalid_chunk = (Metachunk*) top();
529 while (chunk < invalid_chunk ) {
530 assert(chunk->is_tagged_free(), "Should be tagged free");
531 MetaWord* next = ((MetaWord*)chunk) + chunk->word_size();
532 chunk_manager->remove_chunk(chunk);
533 assert(chunk->next() == NULL &&
534 chunk->prev() == NULL,
535 "Was not removed from its list");
536 chunk = (Metachunk*) next;
537 }
538 }
539
540 #ifdef ASSERT
541 uintx VirtualSpaceNode::container_count_slow() {
542 uintx count = 0;
543 Metachunk* chunk = first_chunk();
544 Metachunk* invalid_chunk = (Metachunk*) top();
545 while (chunk < invalid_chunk ) {
546 MetaWord* next = ((MetaWord*)chunk) + chunk->word_size();
547 // Don't count the chunks on the free lists. Those are
548 // still part of the VirtualSpaceNode but not currently
549 // counted.
550 if (!chunk->is_tagged_free()) {
551 count++;
552 }
553 chunk = (Metachunk*) next;
554 }
555 return count;
556 }
557 #endif
558
559 // List of VirtualSpaces for metadata allocation.
560 class VirtualSpaceList : public CHeapObj<mtClass> {
561 friend class VirtualSpaceNode;
562
563 enum VirtualSpaceSizes {
564 VirtualSpaceSize = 256 * K
565 };
566
567 // Head of the list
568 VirtualSpaceNode* _virtual_space_list;
569 // virtual space currently being used for allocations
570 VirtualSpaceNode* _current_virtual_space;
571
572 // Is this VirtualSpaceList used for the compressed class space
573 bool _is_class;
574
575 // Sum of reserved and committed memory in the virtual spaces
576 size_t _reserved_words;
577 size_t _committed_words;
578
579 // Number of virtual spaces
580 size_t _virtual_space_count;
581
582 ~VirtualSpaceList();
583
584 VirtualSpaceNode* virtual_space_list() const { return _virtual_space_list; }
585
586 void set_virtual_space_list(VirtualSpaceNode* v) {
587 _virtual_space_list = v;
588 }
589 void set_current_virtual_space(VirtualSpaceNode* v) {
590 _current_virtual_space = v;
591 }
592
593 void link_vs(VirtualSpaceNode* new_entry);
594
595 // Get another virtual space and add it to the list. This
596 // is typically prompted by a failed attempt to allocate a chunk
597 // and is typically followed by the allocation of a chunk.
598 bool create_new_virtual_space(size_t vs_word_size);
599
600 // Chunk up the unused committed space in the current
601 // virtual space and add the chunks to the free list.
602 void retire_current_virtual_space();
603
604 public:
605 VirtualSpaceList(size_t word_size);
606 VirtualSpaceList(ReservedSpace rs);
607
608 size_t free_bytes();
609
610 Metachunk* get_new_chunk(size_t chunk_word_size,
611 size_t suggested_commit_granularity);
612
613 bool expand_node_by(VirtualSpaceNode* node,
614 size_t min_words,
615 size_t preferred_words);
616
617 bool expand_by(size_t min_words,
618 size_t preferred_words);
619
620 VirtualSpaceNode* current_virtual_space() {
621 return _current_virtual_space;
622 }
623
624 bool is_class() const { return _is_class; }
625
626 bool initialization_succeeded() { return _virtual_space_list != NULL; }
627
628 size_t reserved_words() { return _reserved_words; }
629 size_t reserved_bytes() { return reserved_words() * BytesPerWord; }
630 size_t committed_words() { return _committed_words; }
631 size_t committed_bytes() { return committed_words() * BytesPerWord; }
632
633 void inc_reserved_words(size_t v);
634 void dec_reserved_words(size_t v);
635 void inc_committed_words(size_t v);
636 void dec_committed_words(size_t v);
637 void inc_virtual_space_count();
638 void dec_virtual_space_count();
639
640 bool contains(const void* ptr);
641
642 // Unlink empty VirtualSpaceNodes and free it.
643 void purge(ChunkManager* chunk_manager);
644
645 void print_on(outputStream* st) const;
646
647 class VirtualSpaceListIterator : public StackObj {
648 VirtualSpaceNode* _virtual_spaces;
649 public:
650 VirtualSpaceListIterator(VirtualSpaceNode* virtual_spaces) :
651 _virtual_spaces(virtual_spaces) {}
652
653 bool repeat() {
654 return _virtual_spaces != NULL;
655 }
656
657 VirtualSpaceNode* get_next() {
658 VirtualSpaceNode* result = _virtual_spaces;
659 if (_virtual_spaces != NULL) {
660 _virtual_spaces = _virtual_spaces->next();
661 }
662 return result;
663 }
664 };
665 };
666
667 class Metadebug : AllStatic {
668 // Debugging support for Metaspaces
669 static int _allocation_fail_alot_count;
670
671 public:
672
673 static void init_allocation_fail_alot_count();
674 #ifdef ASSERT
675 static bool test_metadata_failure();
676 #endif
677 };
678
679 int Metadebug::_allocation_fail_alot_count = 0;
680
681 // SpaceManager - used by Metaspace to handle allocations
682 class SpaceManager : public CHeapObj<mtClass> {
683 friend class Metaspace;
684 friend class Metadebug;
685
686 private:
687
688 // protects allocations
689 Mutex* const _lock;
690
691 // Type of metadata allocated.
692 Metaspace::MetadataType _mdtype;
693
694 // List of chunks in use by this SpaceManager. Allocations
695 // are done from the current chunk. The list is used for deallocating
696 // chunks when the SpaceManager is freed.
697 Metachunk* _chunks_in_use[NumberOfInUseLists];
698 Metachunk* _current_chunk;
699
700 // Maximum number of small chunks to allocate to a SpaceManager
701 static uint const _small_chunk_limit;
702
703 // Sum of all space in allocated chunks
704 size_t _allocated_blocks_words;
705
706 // Sum of all allocated chunks
707 size_t _allocated_chunks_words;
708 size_t _allocated_chunks_count;
709
710 // Free lists of blocks are per SpaceManager since they
711 // are assumed to be in chunks in use by the SpaceManager
712 // and all chunks in use by a SpaceManager are freed when
713 // the class loader using the SpaceManager is collected.
714 BlockFreelist* _block_freelists;
715
716 // protects virtualspace and chunk expansions
717 static const char* _expand_lock_name;
718 static const int _expand_lock_rank;
719 static Mutex* const _expand_lock;
720
721 private:
722 // Accessors
723 Metachunk* chunks_in_use(ChunkIndex index) const { return _chunks_in_use[index]; }
724 void set_chunks_in_use(ChunkIndex index, Metachunk* v) {
725 _chunks_in_use[index] = v;
726 }
727
728 BlockFreelist* block_freelists() const { return _block_freelists; }
729
730 Metaspace::MetadataType mdtype() { return _mdtype; }
731
732 VirtualSpaceList* vs_list() const { return Metaspace::get_space_list(_mdtype); }
733 ChunkManager* chunk_manager() const { return Metaspace::get_chunk_manager(_mdtype); }
734
735 Metachunk* current_chunk() const { return _current_chunk; }
736 void set_current_chunk(Metachunk* v) {
737 _current_chunk = v;
738 }
739
740 Metachunk* find_current_chunk(size_t word_size);
741
742 // Add chunk to the list of chunks in use
743 void add_chunk(Metachunk* v, bool make_current);
744 void retire_current_chunk();
745
746 Mutex* lock() const { return _lock; }
747
748 protected:
749 void initialize();
750
751 public:
752 SpaceManager(Metaspace::MetadataType mdtype,
753 Mutex* lock);
754 ~SpaceManager();
755
756 enum ChunkMultiples {
757 MediumChunkMultiple = 4
758 };
759
760 static size_t specialized_chunk_size(bool is_class) { return is_class ? ClassSpecializedChunk : SpecializedChunk; }
761 static size_t small_chunk_size(bool is_class) { return is_class ? ClassSmallChunk : SmallChunk; }
762 static size_t medium_chunk_size(bool is_class) { return is_class ? ClassMediumChunk : MediumChunk; }
763
764 static size_t smallest_chunk_size(bool is_class) { return specialized_chunk_size(is_class); }
765
766 // Accessors
767 bool is_class() const { return _mdtype == Metaspace::ClassType; }
768
769 size_t specialized_chunk_size() const { return specialized_chunk_size(is_class()); }
770 size_t small_chunk_size() const { return small_chunk_size(is_class()); }
771 size_t medium_chunk_size() const { return medium_chunk_size(is_class()); }
772
773 size_t smallest_chunk_size() const { return smallest_chunk_size(is_class()); }
774
775 size_t medium_chunk_bunch() const { return medium_chunk_size() * MediumChunkMultiple; }
776
777 size_t allocated_blocks_words() const { return _allocated_blocks_words; }
778 size_t allocated_blocks_bytes() const { return _allocated_blocks_words * BytesPerWord; }
779 size_t allocated_chunks_words() const { return _allocated_chunks_words; }
780 size_t allocated_chunks_bytes() const { return _allocated_chunks_words * BytesPerWord; }
781 size_t allocated_chunks_count() const { return _allocated_chunks_count; }
782
783 bool is_humongous(size_t word_size) { return word_size > medium_chunk_size(); }
784
785 static Mutex* expand_lock() { return _expand_lock; }
786
787 // Increment the per Metaspace and global running sums for Metachunks
788 // by the given size. This is used when a Metachunk to added to
789 // the in-use list.
790 void inc_size_metrics(size_t words);
791 // Increment the per Metaspace and global running sums Metablocks by the given
792 // size. This is used when a Metablock is allocated.
793 void inc_used_metrics(size_t words);
794 // Delete the portion of the running sums for this SpaceManager. That is,
795 // the globals running sums for the Metachunks and Metablocks are
796 // decremented for all the Metachunks in-use by this SpaceManager.
797 void dec_total_from_size_metrics();
798
799 // Adjust the initial chunk size to match one of the fixed chunk list sizes,
800 // or return the unadjusted size if the requested size is humongous.
801 static size_t adjust_initial_chunk_size(size_t requested, bool is_class_space);
802 size_t adjust_initial_chunk_size(size_t requested) const;
803
804 // Get the initial chunks size for this metaspace type.
805 size_t get_initial_chunk_size(Metaspace::MetaspaceType type) const;
806
807 size_t sum_capacity_in_chunks_in_use() const;
808 size_t sum_used_in_chunks_in_use() const;
809 size_t sum_free_in_chunks_in_use() const;
810 size_t sum_waste_in_chunks_in_use() const;
811 size_t sum_waste_in_chunks_in_use(ChunkIndex index ) const;
812
813 size_t sum_count_in_chunks_in_use();
814 size_t sum_count_in_chunks_in_use(ChunkIndex i);
815
816 Metachunk* get_new_chunk(size_t chunk_word_size);
817
818 // Block allocation and deallocation.
819 // Allocates a block from the current chunk
820 MetaWord* allocate(size_t word_size);
821 // Allocates a block from a small chunk
822 MetaWord* get_small_chunk_and_allocate(size_t word_size);
823
824 // Helper for allocations
825 MetaWord* allocate_work(size_t word_size);
826
827 // Returns a block to the per manager freelist
828 void deallocate(MetaWord* p, size_t word_size);
829
830 // Based on the allocation size and a minimum chunk size,
831 // returned chunk size (for expanding space for chunk allocation).
832 size_t calc_chunk_size(size_t allocation_word_size);
833
834 // Called when an allocation from the current chunk fails.
835 // Gets a new chunk (may require getting a new virtual space),
836 // and allocates from that chunk.
837 MetaWord* grow_and_allocate(size_t word_size);
838
839 // Notify memory usage to MemoryService.
840 void track_metaspace_memory_usage();
841
842 // debugging support.
843
844 void dump(outputStream* const out) const;
845 void print_on(outputStream* st) const;
846 void locked_print_chunks_in_use_on(outputStream* st) const;
847
848 void verify();
849 void verify_chunk_size(Metachunk* chunk);
850 #ifdef ASSERT
851 void verify_allocated_blocks_words();
852 #endif
853
854 // This adjusts the size given to be greater than the minimum allocation size in
855 // words for data in metaspace. Esentially the minimum size is currently 3 words.
856 size_t get_allocation_word_size(size_t word_size) {
857 size_t byte_size = word_size * BytesPerWord;
858
859 size_t raw_bytes_size = MAX2(byte_size, sizeof(Metablock));
860 raw_bytes_size = align_up(raw_bytes_size, Metachunk::object_alignment());
861
862 size_t raw_word_size = raw_bytes_size / BytesPerWord;
863 assert(raw_word_size * BytesPerWord == raw_bytes_size, "Size problem");
864
865 return raw_word_size;
866 }
867 };
868
869 uint const SpaceManager::_small_chunk_limit = 4;
870
871 const char* SpaceManager::_expand_lock_name =
872 "SpaceManager chunk allocation lock";
873 const int SpaceManager::_expand_lock_rank = Monitor::leaf - 1;
874 Mutex* const SpaceManager::_expand_lock =
875 new Mutex(SpaceManager::_expand_lock_rank,
876 SpaceManager::_expand_lock_name,
877 Mutex::_allow_vm_block_flag,
878 Monitor::_safepoint_check_never);
879
880 void VirtualSpaceNode::inc_container_count() {
881 assert_lock_strong(SpaceManager::expand_lock());
882 _container_count++;
883 }
884
885 void VirtualSpaceNode::dec_container_count() {
886 assert_lock_strong(SpaceManager::expand_lock());
887 _container_count--;
888 }
889
890 #ifdef ASSERT
891 void VirtualSpaceNode::verify_container_count() {
892 assert(_container_count == container_count_slow(),
893 "Inconsistency in container_count _container_count " UINTX_FORMAT
894 " container_count_slow() " UINTX_FORMAT, _container_count, container_count_slow());
895 }
896 #endif
897
898 // BlockFreelist methods
899
900 BlockFreelist::BlockFreelist() : _dictionary(new BlockTreeDictionary()), _small_blocks(NULL) {}
901
902 BlockFreelist::~BlockFreelist() {
903 delete _dictionary;
904 if (_small_blocks != NULL) {
905 delete _small_blocks;
906 }
907 }
908
909 void BlockFreelist::return_block(MetaWord* p, size_t word_size) {
910 assert(word_size >= SmallBlocks::small_block_min_size(), "never return dark matter");
911
912 Metablock* free_chunk = ::new (p) Metablock(word_size);
913 if (word_size < SmallBlocks::small_block_max_size()) {
914 small_blocks()->return_block(free_chunk, word_size);
915 } else {
916 dictionary()->return_chunk(free_chunk);
917 }
918 log_trace(gc, metaspace, freelist, blocks)("returning block at " INTPTR_FORMAT " size = "
919 SIZE_FORMAT, p2i(free_chunk), word_size);
920 }
921
922 MetaWord* BlockFreelist::get_block(size_t word_size) {
923 assert(word_size >= SmallBlocks::small_block_min_size(), "never get dark matter");
924
925 // Try small_blocks first.
926 if (word_size < SmallBlocks::small_block_max_size()) {
927 // Don't create small_blocks() until needed. small_blocks() allocates the small block list for
928 // this space manager.
929 MetaWord* new_block = (MetaWord*) small_blocks()->get_block(word_size);
930 if (new_block != NULL) {
931 log_trace(gc, metaspace, freelist, blocks)("getting block at " INTPTR_FORMAT " size = " SIZE_FORMAT,
932 p2i(new_block), word_size);
933 return new_block;
934 }
935 }
936
937 if (word_size < BlockFreelist::min_dictionary_size()) {
938 // If allocation in small blocks fails, this is Dark Matter. Too small for dictionary.
939 return NULL;
940 }
941
942 Metablock* free_block =
943 dictionary()->get_chunk(word_size, FreeBlockDictionary<Metablock>::atLeast);
944 if (free_block == NULL) {
945 return NULL;
946 }
947
948 const size_t block_size = free_block->size();
949 if (block_size > WasteMultiplier * word_size) {
950 return_block((MetaWord*)free_block, block_size);
951 return NULL;
952 }
953
954 MetaWord* new_block = (MetaWord*)free_block;
955 assert(block_size >= word_size, "Incorrect size of block from freelist");
956 const size_t unused = block_size - word_size;
957 if (unused >= SmallBlocks::small_block_min_size()) {
958 return_block(new_block + word_size, unused);
959 }
960
961 log_trace(gc, metaspace, freelist, blocks)("getting block at " INTPTR_FORMAT " size = " SIZE_FORMAT,
962 p2i(new_block), word_size);
963 return new_block;
964 }
965
966 void BlockFreelist::print_on(outputStream* st) const {
967 dictionary()->print_free_lists(st);
968 if (_small_blocks != NULL) {
969 _small_blocks->print_on(st);
970 }
971 }
972
973 // VirtualSpaceNode methods
974
975 VirtualSpaceNode::~VirtualSpaceNode() {
976 _rs.release();
977 #ifdef ASSERT
978 size_t word_size = sizeof(*this) / BytesPerWord;
979 Copy::fill_to_words((HeapWord*) this, word_size, 0xf1f1f1f1);
980 #endif
981 }
982
983 size_t VirtualSpaceNode::used_words_in_vs() const {
984 return pointer_delta(top(), bottom(), sizeof(MetaWord));
985 }
986
987 // Space committed in the VirtualSpace
988 size_t VirtualSpaceNode::capacity_words_in_vs() const {
989 return pointer_delta(end(), bottom(), sizeof(MetaWord));
990 }
991
992 size_t VirtualSpaceNode::free_words_in_vs() const {
993 return pointer_delta(end(), top(), sizeof(MetaWord));
994 }
995
996 // Allocates the chunk from the virtual space only.
997 // This interface is also used internally for debugging. Not all
998 // chunks removed here are necessarily used for allocation.
999 Metachunk* VirtualSpaceNode::take_from_committed(size_t chunk_word_size) {
1000 // Bottom of the new chunk
1001 MetaWord* chunk_limit = top();
1002 assert(chunk_limit != NULL, "Not safe to call this method");
1003
1004 // The virtual spaces are always expanded by the
1005 // commit granularity to enforce the following condition.
1006 // Without this the is_available check will not work correctly.
1007 assert(_virtual_space.committed_size() == _virtual_space.actual_committed_size(),
1008 "The committed memory doesn't match the expanded memory.");
1009
1010 if (!is_available(chunk_word_size)) {
1011 Log(gc, metaspace, freelist) log;
1012 log.debug("VirtualSpaceNode::take_from_committed() not available " SIZE_FORMAT " words ", chunk_word_size);
1013 // Dump some information about the virtual space that is nearly full
1014 ResourceMark rm;
1015 print_on(log.debug_stream());
1016 return NULL;
1017 }
1018
1019 // Take the space (bump top on the current virtual space).
1020 inc_top(chunk_word_size);
1021
1022 // Initialize the chunk
1023 Metachunk* result = ::new (chunk_limit) Metachunk(chunk_word_size, this);
1024 return result;
1025 }
1026
1027
1028 // Expand the virtual space (commit more of the reserved space)
1029 bool VirtualSpaceNode::expand_by(size_t min_words, size_t preferred_words) {
1030 size_t min_bytes = min_words * BytesPerWord;
1031 size_t preferred_bytes = preferred_words * BytesPerWord;
1032
1033 size_t uncommitted = virtual_space()->reserved_size() - virtual_space()->actual_committed_size();
1034
1035 if (uncommitted < min_bytes) {
1036 return false;
1037 }
1038
1039 size_t commit = MIN2(preferred_bytes, uncommitted);
1040 bool result = virtual_space()->expand_by(commit, false);
1041
1042 assert(result, "Failed to commit memory");
1043
1044 return result;
1045 }
1046
1047 Metachunk* VirtualSpaceNode::get_chunk_vs(size_t chunk_word_size) {
1048 assert_lock_strong(SpaceManager::expand_lock());
1049 Metachunk* result = take_from_committed(chunk_word_size);
1050 if (result != NULL) {
1051 inc_container_count();
1052 }
1053 return result;
1054 }
1055
1056 bool VirtualSpaceNode::initialize() {
1057
1058 if (!_rs.is_reserved()) {
1059 return false;
1060 }
1061
1062 // These are necessary restriction to make sure that the virtual space always
1063 // grows in steps of Metaspace::commit_alignment(). If both base and size are
1064 // aligned only the middle alignment of the VirtualSpace is used.
1065 assert_is_aligned(_rs.base(), Metaspace::commit_alignment());
1066 assert_is_aligned(_rs.size(), Metaspace::commit_alignment());
1067
1068 // ReservedSpaces marked as special will have the entire memory
1069 // pre-committed. Setting a committed size will make sure that
1070 // committed_size and actual_committed_size agrees.
1071 size_t pre_committed_size = _rs.special() ? _rs.size() : 0;
1072
1073 bool result = virtual_space()->initialize_with_granularity(_rs, pre_committed_size,
1074 Metaspace::commit_alignment());
1075 if (result) {
1076 assert(virtual_space()->committed_size() == virtual_space()->actual_committed_size(),
1077 "Checking that the pre-committed memory was registered by the VirtualSpace");
1078
1079 set_top((MetaWord*)virtual_space()->low());
1080 set_reserved(MemRegion((HeapWord*)_rs.base(),
1081 (HeapWord*)(_rs.base() + _rs.size())));
1082
1083 assert(reserved()->start() == (HeapWord*) _rs.base(),
1084 "Reserved start was not set properly " PTR_FORMAT
1085 " != " PTR_FORMAT, p2i(reserved()->start()), p2i(_rs.base()));
1086 assert(reserved()->word_size() == _rs.size() / BytesPerWord,
1087 "Reserved size was not set properly " SIZE_FORMAT
1088 " != " SIZE_FORMAT, reserved()->word_size(),
1089 _rs.size() / BytesPerWord);
1090 }
1091
1092 return result;
1093 }
1094
1095 void VirtualSpaceNode::print_on(outputStream* st) const {
1096 size_t used = used_words_in_vs();
1097 size_t capacity = capacity_words_in_vs();
1098 VirtualSpace* vs = virtual_space();
1099 st->print_cr(" space @ " PTR_FORMAT " " SIZE_FORMAT "K, " SIZE_FORMAT_W(3) "%% used "
1100 "[" PTR_FORMAT ", " PTR_FORMAT ", "
1101 PTR_FORMAT ", " PTR_FORMAT ")",
1102 p2i(vs), capacity / K,
1103 capacity == 0 ? 0 : used * 100 / capacity,
1104 p2i(bottom()), p2i(top()), p2i(end()),
1105 p2i(vs->high_boundary()));
1106 }
1107
1108 #ifdef ASSERT
1109 void VirtualSpaceNode::mangle() {
1110 size_t word_size = capacity_words_in_vs();
1111 Copy::fill_to_words((HeapWord*) low(), word_size, 0xf1f1f1f1);
1112 }
1113 #endif // ASSERT
1114
1115 // VirtualSpaceList methods
1116 // Space allocated from the VirtualSpace
1117
1118 VirtualSpaceList::~VirtualSpaceList() {
1119 VirtualSpaceListIterator iter(virtual_space_list());
1120 while (iter.repeat()) {
1121 VirtualSpaceNode* vsl = iter.get_next();
1122 delete vsl;
1123 }
1124 }
1125
1126 void VirtualSpaceList::inc_reserved_words(size_t v) {
1127 assert_lock_strong(SpaceManager::expand_lock());
1128 _reserved_words = _reserved_words + v;
1129 }
1130 void VirtualSpaceList::dec_reserved_words(size_t v) {
1131 assert_lock_strong(SpaceManager::expand_lock());
1132 _reserved_words = _reserved_words - v;
1133 }
1134
1135 #define assert_committed_below_limit() \
1136 assert(MetaspaceAux::committed_bytes() <= MaxMetaspaceSize, \
1137 "Too much committed memory. Committed: " SIZE_FORMAT \
1138 " limit (MaxMetaspaceSize): " SIZE_FORMAT, \
1139 MetaspaceAux::committed_bytes(), MaxMetaspaceSize);
1140
1141 void VirtualSpaceList::inc_committed_words(size_t v) {
1142 assert_lock_strong(SpaceManager::expand_lock());
1143 _committed_words = _committed_words + v;
1144
1145 assert_committed_below_limit();
1146 }
1147 void VirtualSpaceList::dec_committed_words(size_t v) {
1148 assert_lock_strong(SpaceManager::expand_lock());
1149 _committed_words = _committed_words - v;
1150
1151 assert_committed_below_limit();
1152 }
1153
1154 void VirtualSpaceList::inc_virtual_space_count() {
1155 assert_lock_strong(SpaceManager::expand_lock());
1156 _virtual_space_count++;
1157 }
1158 void VirtualSpaceList::dec_virtual_space_count() {
1159 assert_lock_strong(SpaceManager::expand_lock());
1160 _virtual_space_count--;
1161 }
1162
1163 void ChunkManager::remove_chunk(Metachunk* chunk) {
1164 size_t word_size = chunk->word_size();
1165 ChunkIndex index = list_index(word_size);
1166 if (index != HumongousIndex) {
1167 free_chunks(index)->remove_chunk(chunk);
1168 } else {
1169 humongous_dictionary()->remove_chunk(chunk);
1170 }
1171
1172 // Chunk has been removed from the chunks free list, update counters.
1173 account_for_removed_chunk(chunk);
1174 }
1175
1176 // Walk the list of VirtualSpaceNodes and delete
1177 // nodes with a 0 container_count. Remove Metachunks in
1178 // the node from their respective freelists.
1179 void VirtualSpaceList::purge(ChunkManager* chunk_manager) {
1180 assert(SafepointSynchronize::is_at_safepoint(), "must be called at safepoint for contains to work");
1181 assert_lock_strong(SpaceManager::expand_lock());
1182 // Don't use a VirtualSpaceListIterator because this
1183 // list is being changed and a straightforward use of an iterator is not safe.
1184 VirtualSpaceNode* purged_vsl = NULL;
1185 VirtualSpaceNode* prev_vsl = virtual_space_list();
1186 VirtualSpaceNode* next_vsl = prev_vsl;
1187 while (next_vsl != NULL) {
1188 VirtualSpaceNode* vsl = next_vsl;
1189 DEBUG_ONLY(vsl->verify_container_count();)
1190 next_vsl = vsl->next();
1191 // Don't free the current virtual space since it will likely
1192 // be needed soon.
1193 if (vsl->container_count() == 0 && vsl != current_virtual_space()) {
1194 // Unlink it from the list
1195 if (prev_vsl == vsl) {
1196 // This is the case of the current node being the first node.
1197 assert(vsl == virtual_space_list(), "Expected to be the first node");
1198 set_virtual_space_list(vsl->next());
1199 } else {
1200 prev_vsl->set_next(vsl->next());
1201 }
1202
1203 vsl->purge(chunk_manager);
1204 dec_reserved_words(vsl->reserved_words());
1205 dec_committed_words(vsl->committed_words());
1206 dec_virtual_space_count();
1207 purged_vsl = vsl;
1208 delete vsl;
1209 } else {
1210 prev_vsl = vsl;
1211 }
1212 }
1213 #ifdef ASSERT
1214 if (purged_vsl != NULL) {
1215 // List should be stable enough to use an iterator here.
1216 VirtualSpaceListIterator iter(virtual_space_list());
1217 while (iter.repeat()) {
1218 VirtualSpaceNode* vsl = iter.get_next();
1219 assert(vsl != purged_vsl, "Purge of vsl failed");
1220 }
1221 }
1222 #endif
1223 }
1224
1225
1226 // This function looks at the mmap regions in the metaspace without locking.
1227 // The chunks are added with store ordering and not deleted except for at
1228 // unloading time during a safepoint.
1229 bool VirtualSpaceList::contains(const void* ptr) {
1230 // List should be stable enough to use an iterator here because removing virtual
1231 // space nodes is only allowed at a safepoint.
1232 VirtualSpaceListIterator iter(virtual_space_list());
1233 while (iter.repeat()) {
1234 VirtualSpaceNode* vsn = iter.get_next();
1235 if (vsn->contains(ptr)) {
1236 return true;
1237 }
1238 }
1239 return false;
1240 }
1241
1242 void VirtualSpaceList::retire_current_virtual_space() {
1243 assert_lock_strong(SpaceManager::expand_lock());
1244
1245 VirtualSpaceNode* vsn = current_virtual_space();
1246
1247 ChunkManager* cm = is_class() ? Metaspace::chunk_manager_class() :
1248 Metaspace::chunk_manager_metadata();
1249
1250 vsn->retire(cm);
1251 }
1252
1253 void VirtualSpaceNode::retire(ChunkManager* chunk_manager) {
1254 DEBUG_ONLY(verify_container_count();)
1255 for (int i = (int)MediumIndex; i >= (int)ZeroIndex; --i) {
1256 ChunkIndex index = (ChunkIndex)i;
1257 size_t chunk_size = chunk_manager->size_by_index(index);
1258
1259 while (free_words_in_vs() >= chunk_size) {
1260 Metachunk* chunk = get_chunk_vs(chunk_size);
1261 assert(chunk != NULL, "allocation should have been successful");
1262
1263 chunk_manager->return_single_chunk(index, chunk);
1264 }
1265 DEBUG_ONLY(verify_container_count();)
1266 }
1267 assert(free_words_in_vs() == 0, "should be empty now");
1268 }
1269
1270 VirtualSpaceList::VirtualSpaceList(size_t word_size) :
1271 _is_class(false),
1272 _virtual_space_list(NULL),
1273 _current_virtual_space(NULL),
1274 _reserved_words(0),
1275 _committed_words(0),
1276 _virtual_space_count(0) {
1277 MutexLockerEx cl(SpaceManager::expand_lock(),
1278 Mutex::_no_safepoint_check_flag);
1279 create_new_virtual_space(word_size);
1280 }
1281
1282 VirtualSpaceList::VirtualSpaceList(ReservedSpace rs) :
1283 _is_class(true),
1284 _virtual_space_list(NULL),
1285 _current_virtual_space(NULL),
1286 _reserved_words(0),
1287 _committed_words(0),
1288 _virtual_space_count(0) {
1289 MutexLockerEx cl(SpaceManager::expand_lock(),
1290 Mutex::_no_safepoint_check_flag);
1291 VirtualSpaceNode* class_entry = new VirtualSpaceNode(rs);
1292 bool succeeded = class_entry->initialize();
1293 if (succeeded) {
1294 link_vs(class_entry);
1295 }
1296 }
1297
1298 size_t VirtualSpaceList::free_bytes() {
1299 return virtual_space_list()->free_words_in_vs() * BytesPerWord;
1300 }
1301
1302 // Allocate another meta virtual space and add it to the list.
1303 bool VirtualSpaceList::create_new_virtual_space(size_t vs_word_size) {
1304 assert_lock_strong(SpaceManager::expand_lock());
1305
1306 if (is_class()) {
1307 assert(false, "We currently don't support more than one VirtualSpace for"
1308 " the compressed class space. The initialization of the"
1309 " CCS uses another code path and should not hit this path.");
1310 return false;
1311 }
1312
1313 if (vs_word_size == 0) {
1314 assert(false, "vs_word_size should always be at least _reserve_alignment large.");
1315 return false;
1316 }
1317
1318 // Reserve the space
1319 size_t vs_byte_size = vs_word_size * BytesPerWord;
1320 assert_is_aligned(vs_byte_size, Metaspace::reserve_alignment());
1321
1322 // Allocate the meta virtual space and initialize it.
1323 VirtualSpaceNode* new_entry = new VirtualSpaceNode(vs_byte_size);
1324 if (!new_entry->initialize()) {
1325 delete new_entry;
1326 return false;
1327 } else {
1328 assert(new_entry->reserved_words() == vs_word_size,
1329 "Reserved memory size differs from requested memory size");
1330 // ensure lock-free iteration sees fully initialized node
1331 OrderAccess::storestore();
1332 link_vs(new_entry);
1333 return true;
1334 }
1335 }
1336
1337 void VirtualSpaceList::link_vs(VirtualSpaceNode* new_entry) {
1338 if (virtual_space_list() == NULL) {
1339 set_virtual_space_list(new_entry);
1340 } else {
1341 current_virtual_space()->set_next(new_entry);
1342 }
1343 set_current_virtual_space(new_entry);
1344 inc_reserved_words(new_entry->reserved_words());
1345 inc_committed_words(new_entry->committed_words());
1346 inc_virtual_space_count();
1347 #ifdef ASSERT
1348 new_entry->mangle();
1349 #endif
1350 if (log_is_enabled(Trace, gc, metaspace)) {
1351 Log(gc, metaspace) log;
1352 VirtualSpaceNode* vsl = current_virtual_space();
1353 ResourceMark rm;
1354 vsl->print_on(log.trace_stream());
1355 }
1356 }
1357
1358 bool VirtualSpaceList::expand_node_by(VirtualSpaceNode* node,
1359 size_t min_words,
1360 size_t preferred_words) {
1361 size_t before = node->committed_words();
1362
1363 bool result = node->expand_by(min_words, preferred_words);
1364
1365 size_t after = node->committed_words();
1366
1367 // after and before can be the same if the memory was pre-committed.
1368 assert(after >= before, "Inconsistency");
1369 inc_committed_words(after - before);
1370
1371 return result;
1372 }
1373
1374 bool VirtualSpaceList::expand_by(size_t min_words, size_t preferred_words) {
1375 assert_is_aligned(min_words, Metaspace::commit_alignment_words());
1376 assert_is_aligned(preferred_words, Metaspace::commit_alignment_words());
1377 assert(min_words <= preferred_words, "Invalid arguments");
1378
1379 if (!MetaspaceGC::can_expand(min_words, this->is_class())) {
1380 return false;
1381 }
1382
1383 size_t allowed_expansion_words = MetaspaceGC::allowed_expansion();
1384 if (allowed_expansion_words < min_words) {
1385 return false;
1386 }
1387
1388 size_t max_expansion_words = MIN2(preferred_words, allowed_expansion_words);
1389
1390 // Commit more memory from the the current virtual space.
1391 bool vs_expanded = expand_node_by(current_virtual_space(),
1392 min_words,
1393 max_expansion_words);
1394 if (vs_expanded) {
1395 return true;
1396 }
1397 retire_current_virtual_space();
1398
1399 // Get another virtual space.
1400 size_t grow_vs_words = MAX2((size_t)VirtualSpaceSize, preferred_words);
1401 grow_vs_words = align_up(grow_vs_words, Metaspace::reserve_alignment_words());
1402
1403 if (create_new_virtual_space(grow_vs_words)) {
1404 if (current_virtual_space()->is_pre_committed()) {
1405 // The memory was pre-committed, so we are done here.
1406 assert(min_words <= current_virtual_space()->committed_words(),
1407 "The new VirtualSpace was pre-committed, so it"
1408 "should be large enough to fit the alloc request.");
1409 return true;
1410 }
1411
1412 return expand_node_by(current_virtual_space(),
1413 min_words,
1414 max_expansion_words);
1415 }
1416
1417 return false;
1418 }
1419
1420 Metachunk* VirtualSpaceList::get_new_chunk(size_t chunk_word_size, size_t suggested_commit_granularity) {
1421
1422 // Allocate a chunk out of the current virtual space.
1423 Metachunk* next = current_virtual_space()->get_chunk_vs(chunk_word_size);
1424
1425 if (next != NULL) {
1426 return next;
1427 }
1428
1429 // The expand amount is currently only determined by the requested sizes
1430 // and not how much committed memory is left in the current virtual space.
1431
1432 size_t min_word_size = align_up(chunk_word_size, Metaspace::commit_alignment_words());
1433 size_t preferred_word_size = align_up(suggested_commit_granularity, Metaspace::commit_alignment_words());
1434 if (min_word_size >= preferred_word_size) {
1435 // Can happen when humongous chunks are allocated.
1436 preferred_word_size = min_word_size;
1437 }
1438
1439 bool expanded = expand_by(min_word_size, preferred_word_size);
1440 if (expanded) {
1441 next = current_virtual_space()->get_chunk_vs(chunk_word_size);
1442 assert(next != NULL, "The allocation was expected to succeed after the expansion");
1443 }
1444
1445 return next;
1446 }
1447
1448 void VirtualSpaceList::print_on(outputStream* st) const {
1449 VirtualSpaceListIterator iter(virtual_space_list());
1450 while (iter.repeat()) {
1451 VirtualSpaceNode* node = iter.get_next();
1452 node->print_on(st);
1453 }
1454 }
1455
1456 // MetaspaceGC methods
1457
1458 // VM_CollectForMetadataAllocation is the vm operation used to GC.
1459 // Within the VM operation after the GC the attempt to allocate the metadata
1460 // should succeed. If the GC did not free enough space for the metaspace
1461 // allocation, the HWM is increased so that another virtualspace will be
1462 // allocated for the metadata. With perm gen the increase in the perm
1463 // gen had bounds, MinMetaspaceExpansion and MaxMetaspaceExpansion. The
1464 // metaspace policy uses those as the small and large steps for the HWM.
1465 //
1466 // After the GC the compute_new_size() for MetaspaceGC is called to
1467 // resize the capacity of the metaspaces. The current implementation
1468 // is based on the flags MinMetaspaceFreeRatio and MaxMetaspaceFreeRatio used
1469 // to resize the Java heap by some GC's. New flags can be implemented
1470 // if really needed. MinMetaspaceFreeRatio is used to calculate how much
1471 // free space is desirable in the metaspace capacity to decide how much
1472 // to increase the HWM. MaxMetaspaceFreeRatio is used to decide how much
1473 // free space is desirable in the metaspace capacity before decreasing
1474 // the HWM.
1475
1476 // Calculate the amount to increase the high water mark (HWM).
1477 // Increase by a minimum amount (MinMetaspaceExpansion) so that
1478 // another expansion is not requested too soon. If that is not
1479 // enough to satisfy the allocation, increase by MaxMetaspaceExpansion.
1480 // If that is still not enough, expand by the size of the allocation
1481 // plus some.
1482 size_t MetaspaceGC::delta_capacity_until_GC(size_t bytes) {
1483 size_t min_delta = MinMetaspaceExpansion;
1484 size_t max_delta = MaxMetaspaceExpansion;
1485 size_t delta = align_up(bytes, Metaspace::commit_alignment());
1486
1487 if (delta <= min_delta) {
1488 delta = min_delta;
1489 } else if (delta <= max_delta) {
1490 // Don't want to hit the high water mark on the next
1491 // allocation so make the delta greater than just enough
1492 // for this allocation.
1493 delta = max_delta;
1494 } else {
1495 // This allocation is large but the next ones are probably not
1496 // so increase by the minimum.
1497 delta = delta + min_delta;
1498 }
1499
1500 assert_is_aligned(delta, Metaspace::commit_alignment());
1501
1502 return delta;
1503 }
1504
1505 size_t MetaspaceGC::capacity_until_GC() {
1506 size_t value = (size_t)OrderAccess::load_ptr_acquire(&_capacity_until_GC);
1507 assert(value >= MetaspaceSize, "Not initialized properly?");
1508 return value;
1509 }
1510
1511 bool MetaspaceGC::inc_capacity_until_GC(size_t v, size_t* new_cap_until_GC, size_t* old_cap_until_GC) {
1512 assert_is_aligned(v, Metaspace::commit_alignment());
1513
1514 size_t capacity_until_GC = (size_t) _capacity_until_GC;
1515 size_t new_value = capacity_until_GC + v;
1516
1517 if (new_value < capacity_until_GC) {
1518 // The addition wrapped around, set new_value to aligned max value.
1519 new_value = align_down(max_uintx, Metaspace::commit_alignment());
1520 }
1521
1522 intptr_t expected = (intptr_t) capacity_until_GC;
1523 intptr_t actual = Atomic::cmpxchg_ptr((intptr_t) new_value, &_capacity_until_GC, expected);
1524
1525 if (expected != actual) {
1526 return false;
1527 }
1528
1529 if (new_cap_until_GC != NULL) {
1530 *new_cap_until_GC = new_value;
1531 }
1532 if (old_cap_until_GC != NULL) {
1533 *old_cap_until_GC = capacity_until_GC;
1534 }
1535 return true;
1536 }
1537
1538 size_t MetaspaceGC::dec_capacity_until_GC(size_t v) {
1539 assert_is_aligned(v, Metaspace::commit_alignment());
1540
1541 return (size_t)Atomic::add_ptr(-(intptr_t)v, &_capacity_until_GC);
1542 }
1543
1544 void MetaspaceGC::initialize() {
1545 // Set the high-water mark to MaxMetapaceSize during VM initializaton since
1546 // we can't do a GC during initialization.
1547 _capacity_until_GC = MaxMetaspaceSize;
1548 }
1549
1550 void MetaspaceGC::post_initialize() {
1551 // Reset the high-water mark once the VM initialization is done.
1552 _capacity_until_GC = MAX2(MetaspaceAux::committed_bytes(), MetaspaceSize);
1553 }
1554
1555 bool MetaspaceGC::can_expand(size_t word_size, bool is_class) {
1556 // Check if the compressed class space is full.
1557 if (is_class && Metaspace::using_class_space()) {
1558 size_t class_committed = MetaspaceAux::committed_bytes(Metaspace::ClassType);
1559 if (class_committed + word_size * BytesPerWord > CompressedClassSpaceSize) {
1560 return false;
1561 }
1562 }
1563
1564 // Check if the user has imposed a limit on the metaspace memory.
1565 size_t committed_bytes = MetaspaceAux::committed_bytes();
1566 if (committed_bytes + word_size * BytesPerWord > MaxMetaspaceSize) {
1567 return false;
1568 }
1569
1570 return true;
1571 }
1572
1573 size_t MetaspaceGC::allowed_expansion() {
1574 size_t committed_bytes = MetaspaceAux::committed_bytes();
1575 size_t capacity_until_gc = capacity_until_GC();
1576
1577 assert(capacity_until_gc >= committed_bytes,
1578 "capacity_until_gc: " SIZE_FORMAT " < committed_bytes: " SIZE_FORMAT,
1579 capacity_until_gc, committed_bytes);
1580
1581 size_t left_until_max = MaxMetaspaceSize - committed_bytes;
1582 size_t left_until_GC = capacity_until_gc - committed_bytes;
1583 size_t left_to_commit = MIN2(left_until_GC, left_until_max);
1584
1585 return left_to_commit / BytesPerWord;
1586 }
1587
1588 void MetaspaceGC::compute_new_size() {
1589 assert(_shrink_factor <= 100, "invalid shrink factor");
1590 uint current_shrink_factor = _shrink_factor;
1591 _shrink_factor = 0;
1592
1593 // Using committed_bytes() for used_after_gc is an overestimation, since the
1594 // chunk free lists are included in committed_bytes() and the memory in an
1595 // un-fragmented chunk free list is available for future allocations.
1596 // However, if the chunk free lists becomes fragmented, then the memory may
1597 // not be available for future allocations and the memory is therefore "in use".
1598 // Including the chunk free lists in the definition of "in use" is therefore
1599 // necessary. Not including the chunk free lists can cause capacity_until_GC to
1600 // shrink below committed_bytes() and this has caused serious bugs in the past.
1601 const size_t used_after_gc = MetaspaceAux::committed_bytes();
1602 const size_t capacity_until_GC = MetaspaceGC::capacity_until_GC();
1603
1604 const double minimum_free_percentage = MinMetaspaceFreeRatio / 100.0;
1605 const double maximum_used_percentage = 1.0 - minimum_free_percentage;
1606
1607 const double min_tmp = used_after_gc / maximum_used_percentage;
1608 size_t minimum_desired_capacity =
1609 (size_t)MIN2(min_tmp, double(max_uintx));
1610 // Don't shrink less than the initial generation size
1611 minimum_desired_capacity = MAX2(minimum_desired_capacity,
1612 MetaspaceSize);
1613
1614 log_trace(gc, metaspace)("MetaspaceGC::compute_new_size: ");
1615 log_trace(gc, metaspace)(" minimum_free_percentage: %6.2f maximum_used_percentage: %6.2f",
1616 minimum_free_percentage, maximum_used_percentage);
1617 log_trace(gc, metaspace)(" used_after_gc : %6.1fKB", used_after_gc / (double) K);
1618
1619
1620 size_t shrink_bytes = 0;
1621 if (capacity_until_GC < minimum_desired_capacity) {
1622 // If we have less capacity below the metaspace HWM, then
1623 // increment the HWM.
1624 size_t expand_bytes = minimum_desired_capacity - capacity_until_GC;
1625 expand_bytes = align_up(expand_bytes, Metaspace::commit_alignment());
1626 // Don't expand unless it's significant
1627 if (expand_bytes >= MinMetaspaceExpansion) {
1628 size_t new_capacity_until_GC = 0;
1629 bool succeeded = MetaspaceGC::inc_capacity_until_GC(expand_bytes, &new_capacity_until_GC);
1630 assert(succeeded, "Should always succesfully increment HWM when at safepoint");
1631
1632 Metaspace::tracer()->report_gc_threshold(capacity_until_GC,
1633 new_capacity_until_GC,
1634 MetaspaceGCThresholdUpdater::ComputeNewSize);
1635 log_trace(gc, metaspace)(" expanding: minimum_desired_capacity: %6.1fKB expand_bytes: %6.1fKB MinMetaspaceExpansion: %6.1fKB new metaspace HWM: %6.1fKB",
1636 minimum_desired_capacity / (double) K,
1637 expand_bytes / (double) K,
1638 MinMetaspaceExpansion / (double) K,
1639 new_capacity_until_GC / (double) K);
1640 }
1641 return;
1642 }
1643
1644 // No expansion, now see if we want to shrink
1645 // We would never want to shrink more than this
1646 assert(capacity_until_GC >= minimum_desired_capacity,
1647 SIZE_FORMAT " >= " SIZE_FORMAT,
1648 capacity_until_GC, minimum_desired_capacity);
1649 size_t max_shrink_bytes = capacity_until_GC - minimum_desired_capacity;
1650
1651 // Should shrinking be considered?
1652 if (MaxMetaspaceFreeRatio < 100) {
1653 const double maximum_free_percentage = MaxMetaspaceFreeRatio / 100.0;
1654 const double minimum_used_percentage = 1.0 - maximum_free_percentage;
1655 const double max_tmp = used_after_gc / minimum_used_percentage;
1656 size_t maximum_desired_capacity = (size_t)MIN2(max_tmp, double(max_uintx));
1657 maximum_desired_capacity = MAX2(maximum_desired_capacity,
1658 MetaspaceSize);
1659 log_trace(gc, metaspace)(" maximum_free_percentage: %6.2f minimum_used_percentage: %6.2f",
1660 maximum_free_percentage, minimum_used_percentage);
1661 log_trace(gc, metaspace)(" minimum_desired_capacity: %6.1fKB maximum_desired_capacity: %6.1fKB",
1662 minimum_desired_capacity / (double) K, maximum_desired_capacity / (double) K);
1663
1664 assert(minimum_desired_capacity <= maximum_desired_capacity,
1665 "sanity check");
1666
1667 if (capacity_until_GC > maximum_desired_capacity) {
1668 // Capacity too large, compute shrinking size
1669 shrink_bytes = capacity_until_GC - maximum_desired_capacity;
1670 // We don't want shrink all the way back to initSize if people call
1671 // System.gc(), because some programs do that between "phases" and then
1672 // we'd just have to grow the heap up again for the next phase. So we
1673 // damp the shrinking: 0% on the first call, 10% on the second call, 40%
1674 // on the third call, and 100% by the fourth call. But if we recompute
1675 // size without shrinking, it goes back to 0%.
1676 shrink_bytes = shrink_bytes / 100 * current_shrink_factor;
1677
1678 shrink_bytes = align_down(shrink_bytes, Metaspace::commit_alignment());
1679
1680 assert(shrink_bytes <= max_shrink_bytes,
1681 "invalid shrink size " SIZE_FORMAT " not <= " SIZE_FORMAT,
1682 shrink_bytes, max_shrink_bytes);
1683 if (current_shrink_factor == 0) {
1684 _shrink_factor = 10;
1685 } else {
1686 _shrink_factor = MIN2(current_shrink_factor * 4, (uint) 100);
1687 }
1688 log_trace(gc, metaspace)(" shrinking: initThreshold: %.1fK maximum_desired_capacity: %.1fK",
1689 MetaspaceSize / (double) K, maximum_desired_capacity / (double) K);
1690 log_trace(gc, metaspace)(" shrink_bytes: %.1fK current_shrink_factor: %d new shrink factor: %d MinMetaspaceExpansion: %.1fK",
1691 shrink_bytes / (double) K, current_shrink_factor, _shrink_factor, MinMetaspaceExpansion / (double) K);
1692 }
1693 }
1694
1695 // Don't shrink unless it's significant
1696 if (shrink_bytes >= MinMetaspaceExpansion &&
1697 ((capacity_until_GC - shrink_bytes) >= MetaspaceSize)) {
1698 size_t new_capacity_until_GC = MetaspaceGC::dec_capacity_until_GC(shrink_bytes);
1699 Metaspace::tracer()->report_gc_threshold(capacity_until_GC,
1700 new_capacity_until_GC,
1701 MetaspaceGCThresholdUpdater::ComputeNewSize);
1702 }
1703 }
1704
1705 // Metadebug methods
1706
1707 void Metadebug::init_allocation_fail_alot_count() {
1708 if (MetadataAllocationFailALot) {
1709 _allocation_fail_alot_count =
1710 1+(long)((double)MetadataAllocationFailALotInterval*os::random()/(max_jint+1.0));
1711 }
1712 }
1713
1714 #ifdef ASSERT
1715 bool Metadebug::test_metadata_failure() {
1716 if (MetadataAllocationFailALot &&
1717 Threads::is_vm_complete()) {
1718 if (_allocation_fail_alot_count > 0) {
1719 _allocation_fail_alot_count--;
1720 } else {
1721 log_trace(gc, metaspace, freelist)("Metadata allocation failing for MetadataAllocationFailALot");
1722 init_allocation_fail_alot_count();
1723 return true;
1724 }
1725 }
1726 return false;
1727 }
1728 #endif
1729
1730 // ChunkManager methods
1731
1732 size_t ChunkManager::free_chunks_total_words() {
1733 return _free_chunks_total;
1734 }
1735
1736 size_t ChunkManager::free_chunks_total_bytes() {
1737 return free_chunks_total_words() * BytesPerWord;
1738 }
1739
1740 // Update internal accounting after a chunk was added
1741 void ChunkManager::account_for_added_chunk(const Metachunk* c) {
1742 assert_lock_strong(SpaceManager::expand_lock());
1743 _free_chunks_count ++;
1744 _free_chunks_total += c->word_size();
1745 }
1746
1747 // Update internal accounting after a chunk was removed
1748 void ChunkManager::account_for_removed_chunk(const Metachunk* c) {
1749 assert_lock_strong(SpaceManager::expand_lock());
1750 assert(_free_chunks_count >= 1,
1751 "ChunkManager::_free_chunks_count: about to go negative (" SIZE_FORMAT ").", _free_chunks_count);
1752 assert(_free_chunks_total >= c->word_size(),
1753 "ChunkManager::_free_chunks_total: about to go negative"
1754 "(now: " SIZE_FORMAT ", decrement value: " SIZE_FORMAT ").", _free_chunks_total, c->word_size());
1755 _free_chunks_count --;
1756 _free_chunks_total -= c->word_size();
1757 }
1758
1759 size_t ChunkManager::free_chunks_count() {
1760 #ifdef ASSERT
1761 if (!UseConcMarkSweepGC && !SpaceManager::expand_lock()->is_locked()) {
1762 MutexLockerEx cl(SpaceManager::expand_lock(),
1763 Mutex::_no_safepoint_check_flag);
1764 // This lock is only needed in debug because the verification
1765 // of the _free_chunks_totals walks the list of free chunks
1766 slow_locked_verify_free_chunks_count();
1767 }
1768 #endif
1769 return _free_chunks_count;
1770 }
1771
1772 ChunkIndex ChunkManager::list_index(size_t size) {
1773 if (size_by_index(SpecializedIndex) == size) {
1774 return SpecializedIndex;
1775 }
1776 if (size_by_index(SmallIndex) == size) {
1777 return SmallIndex;
1778 }
1779 const size_t med_size = size_by_index(MediumIndex);
1780 if (med_size == size) {
1781 return MediumIndex;
1782 }
1783
1784 assert(size > med_size, "Not a humongous chunk");
1785 return HumongousIndex;
1786 }
1787
1788 size_t ChunkManager::size_by_index(ChunkIndex index) {
1789 index_bounds_check(index);
1790 assert(index != HumongousIndex, "Do not call for humongous chunks.");
1791 return free_chunks(index)->size();
1792 }
1793
1794 void ChunkManager::locked_verify_free_chunks_total() {
1795 assert_lock_strong(SpaceManager::expand_lock());
1796 assert(sum_free_chunks() == _free_chunks_total,
1797 "_free_chunks_total " SIZE_FORMAT " is not the"
1798 " same as sum " SIZE_FORMAT, _free_chunks_total,
1799 sum_free_chunks());
1800 }
1801
1802 void ChunkManager::verify_free_chunks_total() {
1803 MutexLockerEx cl(SpaceManager::expand_lock(),
1804 Mutex::_no_safepoint_check_flag);
1805 locked_verify_free_chunks_total();
1806 }
1807
1808 void ChunkManager::locked_verify_free_chunks_count() {
1809 assert_lock_strong(SpaceManager::expand_lock());
1810 assert(sum_free_chunks_count() == _free_chunks_count,
1811 "_free_chunks_count " SIZE_FORMAT " is not the"
1812 " same as sum " SIZE_FORMAT, _free_chunks_count,
1813 sum_free_chunks_count());
1814 }
1815
1816 void ChunkManager::verify_free_chunks_count() {
1817 #ifdef ASSERT
1818 MutexLockerEx cl(SpaceManager::expand_lock(),
1819 Mutex::_no_safepoint_check_flag);
1820 locked_verify_free_chunks_count();
1821 #endif
1822 }
1823
1824 void ChunkManager::verify() {
1825 MutexLockerEx cl(SpaceManager::expand_lock(),
1826 Mutex::_no_safepoint_check_flag);
1827 locked_verify();
1828 }
1829
1830 void ChunkManager::locked_verify() {
1831 locked_verify_free_chunks_count();
1832 locked_verify_free_chunks_total();
1833 }
1834
1835 void ChunkManager::locked_print_free_chunks(outputStream* st) {
1836 assert_lock_strong(SpaceManager::expand_lock());
1837 st->print_cr("Free chunk total " SIZE_FORMAT " count " SIZE_FORMAT,
1838 _free_chunks_total, _free_chunks_count);
1839 }
1840
1841 void ChunkManager::locked_print_sum_free_chunks(outputStream* st) {
1842 assert_lock_strong(SpaceManager::expand_lock());
1843 st->print_cr("Sum free chunk total " SIZE_FORMAT " count " SIZE_FORMAT,
1844 sum_free_chunks(), sum_free_chunks_count());
1845 }
1846
1847 ChunkList* ChunkManager::free_chunks(ChunkIndex index) {
1848 assert(index == SpecializedIndex || index == SmallIndex || index == MediumIndex,
1849 "Bad index: %d", (int)index);
1850
1851 return &_free_chunks[index];
1852 }
1853
1854 // These methods that sum the free chunk lists are used in printing
1855 // methods that are used in product builds.
1856 size_t ChunkManager::sum_free_chunks() {
1857 assert_lock_strong(SpaceManager::expand_lock());
1858 size_t result = 0;
1859 for (ChunkIndex i = ZeroIndex; i < NumberOfFreeLists; i = next_chunk_index(i)) {
1860 ChunkList* list = free_chunks(i);
1861
1862 if (list == NULL) {
1863 continue;
1864 }
1865
1866 result = result + list->count() * list->size();
1867 }
1868 result = result + humongous_dictionary()->total_size();
1869 return result;
1870 }
1871
1872 size_t ChunkManager::sum_free_chunks_count() {
1873 assert_lock_strong(SpaceManager::expand_lock());
1874 size_t count = 0;
1875 for (ChunkIndex i = ZeroIndex; i < NumberOfFreeLists; i = next_chunk_index(i)) {
1876 ChunkList* list = free_chunks(i);
1877 if (list == NULL) {
1878 continue;
1879 }
1880 count = count + list->count();
1881 }
1882 count = count + humongous_dictionary()->total_free_blocks();
1883 return count;
1884 }
1885
1886 ChunkList* ChunkManager::find_free_chunks_list(size_t word_size) {
1887 ChunkIndex index = list_index(word_size);
1888 assert(index < HumongousIndex, "No humongous list");
1889 return free_chunks(index);
1890 }
1891
1892 Metachunk* ChunkManager::free_chunks_get(size_t word_size) {
1893 assert_lock_strong(SpaceManager::expand_lock());
1894
1895 slow_locked_verify();
1896
1897 Metachunk* chunk = NULL;
1898 if (list_index(word_size) != HumongousIndex) {
1899 ChunkList* free_list = find_free_chunks_list(word_size);
1900 assert(free_list != NULL, "Sanity check");
1901
1902 chunk = free_list->head();
1903
1904 if (chunk == NULL) {
1905 return NULL;
1906 }
1907
1908 // Remove the chunk as the head of the list.
1909 free_list->remove_chunk(chunk);
1910
1911 log_trace(gc, metaspace, freelist)("ChunkManager::free_chunks_get: free_list " PTR_FORMAT " head " PTR_FORMAT " size " SIZE_FORMAT,
1912 p2i(free_list), p2i(chunk), chunk->word_size());
1913 } else {
1914 chunk = humongous_dictionary()->get_chunk(
1915 word_size,
1916 FreeBlockDictionary<Metachunk>::atLeast);
1917
1918 if (chunk == NULL) {
1919 return NULL;
1920 }
1921
1922 log_debug(gc, metaspace, alloc)("Free list allocate humongous chunk size " SIZE_FORMAT " for requested size " SIZE_FORMAT " waste " SIZE_FORMAT,
1923 chunk->word_size(), word_size, chunk->word_size() - word_size);
1924 }
1925
1926 // Chunk has been removed from the chunk manager; update counters.
1927 account_for_removed_chunk(chunk);
1928
1929 // Remove it from the links to this freelist
1930 chunk->set_next(NULL);
1931 chunk->set_prev(NULL);
1932 #ifdef ASSERT
1933 // Chunk is no longer on any freelist. Setting to false make container_count_slow()
1934 // work.
1935 chunk->set_is_tagged_free(false);
1936 #endif
1937 chunk->container()->inc_container_count();
1938
1939 slow_locked_verify();
1940 return chunk;
1941 }
1942
1943 Metachunk* ChunkManager::chunk_freelist_allocate(size_t word_size) {
1944 assert_lock_strong(SpaceManager::expand_lock());
1945 slow_locked_verify();
1946
1947 // Take from the beginning of the list
1948 Metachunk* chunk = free_chunks_get(word_size);
1949 if (chunk == NULL) {
1950 return NULL;
1951 }
1952
1953 assert((word_size <= chunk->word_size()) ||
1954 (list_index(chunk->word_size()) == HumongousIndex),
1955 "Non-humongous variable sized chunk");
1956 Log(gc, metaspace, freelist) log;
1957 if (log.is_debug()) {
1958 size_t list_count;
1959 if (list_index(word_size) < HumongousIndex) {
1960 ChunkList* list = find_free_chunks_list(word_size);
1961 list_count = list->count();
1962 } else {
1963 list_count = humongous_dictionary()->total_count();
1964 }
1965 log.debug("ChunkManager::chunk_freelist_allocate: " PTR_FORMAT " chunk " PTR_FORMAT " size " SIZE_FORMAT " count " SIZE_FORMAT " ",
1966 p2i(this), p2i(chunk), chunk->word_size(), list_count);
1967 ResourceMark rm;
1968 locked_print_free_chunks(log.debug_stream());
1969 }
1970
1971 return chunk;
1972 }
1973
1974 void ChunkManager::return_single_chunk(ChunkIndex index, Metachunk* chunk) {
1975 assert_lock_strong(SpaceManager::expand_lock());
1976 assert(chunk != NULL, "Expected chunk.");
1977 assert(chunk->container() != NULL, "Container should have been set.");
1978 assert(chunk->is_tagged_free() == false, "Chunk should be in use.");
1979 index_bounds_check(index);
1980
1981 // Note: mangle *before* returning the chunk to the freelist or dictionary. It does not
1982 // matter for the freelist (non-humongous chunks), but the humongous chunk dictionary
1983 // keeps tree node pointers in the chunk payload area which mangle will overwrite.
1984 NOT_PRODUCT(chunk->mangle(badMetaWordVal);)
1985
1986 if (index != HumongousIndex) {
1987 // Return non-humongous chunk to freelist.
1988 ChunkList* list = free_chunks(index);
1989 assert(list->size() == chunk->word_size(), "Wrong chunk type.");
1990 list->return_chunk_at_head(chunk);
1991 log_trace(gc, metaspace, freelist)("returned one %s chunk at " PTR_FORMAT " to freelist.",
1992 chunk_size_name(index), p2i(chunk));
1993 } else {
1994 // Return humongous chunk to dictionary.
1995 assert(chunk->word_size() > free_chunks(MediumIndex)->size(), "Wrong chunk type.");
1996 assert(chunk->word_size() % free_chunks(SpecializedIndex)->size() == 0,
1997 "Humongous chunk has wrong alignment.");
1998 _humongous_dictionary.return_chunk(chunk);
1999 log_trace(gc, metaspace, freelist)("returned one %s chunk at " PTR_FORMAT " (word size " SIZE_FORMAT ") to freelist.",
2000 chunk_size_name(index), p2i(chunk), chunk->word_size());
2001 }
2002 chunk->container()->dec_container_count();
2003 DEBUG_ONLY(chunk->set_is_tagged_free(true);)
2004
2005 // Chunk has been added; update counters.
2006 account_for_added_chunk(chunk);
2007
2008 }
2009
2010 void ChunkManager::return_chunk_list(ChunkIndex index, Metachunk* chunks) {
2011 index_bounds_check(index);
2012 if (chunks == NULL) {
2013 return;
2014 }
2015 LogTarget(Trace, gc, metaspace, freelist) log;
2016 if (log.is_enabled()) { // tracing
2017 log.print("returning list of %s chunks...", chunk_size_name(index));
2018 }
2019 unsigned num_chunks_returned = 0;
2020 size_t size_chunks_returned = 0;
2021 Metachunk* cur = chunks;
2022 while (cur != NULL) {
2023 // Capture the next link before it is changed
2024 // by the call to return_chunk_at_head();
2025 Metachunk* next = cur->next();
2026 if (log.is_enabled()) { // tracing
2027 num_chunks_returned ++;
2028 size_chunks_returned += cur->word_size();
2029 }
2030 return_single_chunk(index, cur);
2031 cur = next;
2032 }
2033 if (log.is_enabled()) { // tracing
2034 log.print("returned %u %s chunks to freelist, total word size " SIZE_FORMAT ".",
2035 num_chunks_returned, chunk_size_name(index), size_chunks_returned);
2036 if (index != HumongousIndex) {
2037 log.print("updated freelist count: " SIZE_FORMAT ".", free_chunks(index)->size());
2038 } else {
2039 log.print("updated dictionary count " SIZE_FORMAT ".", _humongous_dictionary.total_count());
2040 }
2041 }
2042 }
2043
2044 void ChunkManager::print_on(outputStream* out) const {
2045 const_cast<ChunkManager *>(this)->humongous_dictionary()->report_statistics(out);
2046 }
2047
2048 // SpaceManager methods
2049
2050 size_t SpaceManager::adjust_initial_chunk_size(size_t requested, bool is_class_space) {
2051 size_t chunk_sizes[] = {
2052 specialized_chunk_size(is_class_space),
2053 small_chunk_size(is_class_space),
2054 medium_chunk_size(is_class_space)
2055 };
2056
2057 // Adjust up to one of the fixed chunk sizes ...
2058 for (size_t i = 0; i < ARRAY_SIZE(chunk_sizes); i++) {
2059 if (requested <= chunk_sizes[i]) {
2060 return chunk_sizes[i];
2061 }
2062 }
2063
2064 // ... or return the size as a humongous chunk.
2065 return requested;
2066 }
2067
2068 size_t SpaceManager::adjust_initial_chunk_size(size_t requested) const {
2069 return adjust_initial_chunk_size(requested, is_class());
2070 }
2071
2072 size_t SpaceManager::get_initial_chunk_size(Metaspace::MetaspaceType type) const {
2073 size_t requested;
2074
2075 if (is_class()) {
2076 switch (type) {
2077 case Metaspace::BootMetaspaceType: requested = Metaspace::first_class_chunk_word_size(); break;
2078 case Metaspace::ROMetaspaceType: requested = ClassSpecializedChunk; break;
2079 case Metaspace::ReadWriteMetaspaceType: requested = ClassSpecializedChunk; break;
2080 case Metaspace::AnonymousMetaspaceType: requested = ClassSpecializedChunk; break;
2081 case Metaspace::ReflectionMetaspaceType: requested = ClassSpecializedChunk; break;
2082 default: requested = ClassSmallChunk; break;
2083 }
2084 } else {
2085 switch (type) {
2086 case Metaspace::BootMetaspaceType: requested = Metaspace::first_chunk_word_size(); break;
2087 case Metaspace::ROMetaspaceType: requested = SharedReadOnlySize / wordSize; break;
2088 case Metaspace::ReadWriteMetaspaceType: requested = SharedReadWriteSize / wordSize; break;
2089 case Metaspace::AnonymousMetaspaceType: requested = SpecializedChunk; break;
2090 case Metaspace::ReflectionMetaspaceType: requested = SpecializedChunk; break;
2091 default: requested = SmallChunk; break;
2092 }
2093 }
2094
2095 // Adjust to one of the fixed chunk sizes (unless humongous)
2096 const size_t adjusted = adjust_initial_chunk_size(requested);
2097
2098 assert(adjusted != 0, "Incorrect initial chunk size. Requested: "
2099 SIZE_FORMAT " adjusted: " SIZE_FORMAT, requested, adjusted);
2100
2101 return adjusted;
2102 }
2103
2104 size_t SpaceManager::sum_free_in_chunks_in_use() const {
2105 MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag);
2106 size_t free = 0;
2107 for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) {
2108 Metachunk* chunk = chunks_in_use(i);
2109 while (chunk != NULL) {
2110 free += chunk->free_word_size();
2111 chunk = chunk->next();
2112 }
2113 }
2114 return free;
2115 }
2116
2117 size_t SpaceManager::sum_waste_in_chunks_in_use() const {
2118 MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag);
2119 size_t result = 0;
2120 for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) {
2121 result += sum_waste_in_chunks_in_use(i);
2122 }
2123
2124 return result;
2125 }
2126
2127 size_t SpaceManager::sum_waste_in_chunks_in_use(ChunkIndex index) const {
2128 size_t result = 0;
2129 Metachunk* chunk = chunks_in_use(index);
2130 // Count the free space in all the chunk but not the
2131 // current chunk from which allocations are still being done.
2132 while (chunk != NULL) {
2133 if (chunk != current_chunk()) {
2134 result += chunk->free_word_size();
2135 }
2136 chunk = chunk->next();
2137 }
2138 return result;
2139 }
2140
2141 size_t SpaceManager::sum_capacity_in_chunks_in_use() const {
2142 // For CMS use "allocated_chunks_words()" which does not need the
2143 // Metaspace lock. For the other collectors sum over the
2144 // lists. Use both methods as a check that "allocated_chunks_words()"
2145 // is correct. That is, sum_capacity_in_chunks() is too expensive
2146 // to use in the product and allocated_chunks_words() should be used
2147 // but allow for checking that allocated_chunks_words() returns the same
2148 // value as sum_capacity_in_chunks_in_use() which is the definitive
2149 // answer.
2150 if (UseConcMarkSweepGC) {
2151 return allocated_chunks_words();
2152 } else {
2153 MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag);
2154 size_t sum = 0;
2155 for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) {
2156 Metachunk* chunk = chunks_in_use(i);
2157 while (chunk != NULL) {
2158 sum += chunk->word_size();
2159 chunk = chunk->next();
2160 }
2161 }
2162 return sum;
2163 }
2164 }
2165
2166 size_t SpaceManager::sum_count_in_chunks_in_use() {
2167 size_t count = 0;
2168 for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) {
2169 count = count + sum_count_in_chunks_in_use(i);
2170 }
2171
2172 return count;
2173 }
2174
2175 size_t SpaceManager::sum_count_in_chunks_in_use(ChunkIndex i) {
2176 size_t count = 0;
2177 Metachunk* chunk = chunks_in_use(i);
2178 while (chunk != NULL) {
2179 count++;
2180 chunk = chunk->next();
2181 }
2182 return count;
2183 }
2184
2185
2186 size_t SpaceManager::sum_used_in_chunks_in_use() const {
2187 MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag);
2188 size_t used = 0;
2189 for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) {
2190 Metachunk* chunk = chunks_in_use(i);
2191 while (chunk != NULL) {
2192 used += chunk->used_word_size();
2193 chunk = chunk->next();
2194 }
2195 }
2196 return used;
2197 }
2198
2199 void SpaceManager::locked_print_chunks_in_use_on(outputStream* st) const {
2200
2201 for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) {
2202 Metachunk* chunk = chunks_in_use(i);
2203 st->print("SpaceManager: %s " PTR_FORMAT,
2204 chunk_size_name(i), p2i(chunk));
2205 if (chunk != NULL) {
2206 st->print_cr(" free " SIZE_FORMAT,
2207 chunk->free_word_size());
2208 } else {
2209 st->cr();
2210 }
2211 }
2212
2213 chunk_manager()->locked_print_free_chunks(st);
2214 chunk_manager()->locked_print_sum_free_chunks(st);
2215 }
2216
2217 size_t SpaceManager::calc_chunk_size(size_t word_size) {
2218
2219 // Decide between a small chunk and a medium chunk. Up to
2220 // _small_chunk_limit small chunks can be allocated.
2221 // After that a medium chunk is preferred.
2222 size_t chunk_word_size;
2223 if (chunks_in_use(MediumIndex) == NULL &&
2224 sum_count_in_chunks_in_use(SmallIndex) < _small_chunk_limit) {
2225 chunk_word_size = (size_t) small_chunk_size();
2226 if (word_size + Metachunk::overhead() > small_chunk_size()) {
2227 chunk_word_size = medium_chunk_size();
2228 }
2229 } else {
2230 chunk_word_size = medium_chunk_size();
2231 }
2232
2233 // Might still need a humongous chunk. Enforce
2234 // humongous allocations sizes to be aligned up to
2235 // the smallest chunk size.
2236 size_t if_humongous_sized_chunk =
2237 align_up(word_size + Metachunk::overhead(),
2238 smallest_chunk_size());
2239 chunk_word_size =
2240 MAX2((size_t) chunk_word_size, if_humongous_sized_chunk);
2241
2242 assert(!SpaceManager::is_humongous(word_size) ||
2243 chunk_word_size == if_humongous_sized_chunk,
2244 "Size calculation is wrong, word_size " SIZE_FORMAT
2245 " chunk_word_size " SIZE_FORMAT,
2246 word_size, chunk_word_size);
2247 Log(gc, metaspace, alloc) log;
2248 if (log.is_debug() && SpaceManager::is_humongous(word_size)) {
2249 log.debug("Metadata humongous allocation:");
2250 log.debug(" word_size " PTR_FORMAT, word_size);
2251 log.debug(" chunk_word_size " PTR_FORMAT, chunk_word_size);
2252 log.debug(" chunk overhead " PTR_FORMAT, Metachunk::overhead());
2253 }
2254 return chunk_word_size;
2255 }
2256
2257 void SpaceManager::track_metaspace_memory_usage() {
2258 if (is_init_completed()) {
2259 if (is_class()) {
2260 MemoryService::track_compressed_class_memory_usage();
2261 }
2262 MemoryService::track_metaspace_memory_usage();
2263 }
2264 }
2265
2266 MetaWord* SpaceManager::grow_and_allocate(size_t word_size) {
2267 assert(vs_list()->current_virtual_space() != NULL,
2268 "Should have been set");
2269 assert(current_chunk() == NULL ||
2270 current_chunk()->allocate(word_size) == NULL,
2271 "Don't need to expand");
2272 MutexLockerEx cl(SpaceManager::expand_lock(), Mutex::_no_safepoint_check_flag);
2273
2274 if (log_is_enabled(Trace, gc, metaspace, freelist)) {
2275 size_t words_left = 0;
2276 size_t words_used = 0;
2277 if (current_chunk() != NULL) {
2278 words_left = current_chunk()->free_word_size();
2279 words_used = current_chunk()->used_word_size();
2280 }
2281 log_trace(gc, metaspace, freelist)("SpaceManager::grow_and_allocate for " SIZE_FORMAT " words " SIZE_FORMAT " words used " SIZE_FORMAT " words left",
2282 word_size, words_used, words_left);
2283 }
2284
2285 // Get another chunk
2286 size_t chunk_word_size = calc_chunk_size(word_size);
2287 Metachunk* next = get_new_chunk(chunk_word_size);
2288
2289 MetaWord* mem = NULL;
2290
2291 // If a chunk was available, add it to the in-use chunk list
2292 // and do an allocation from it.
2293 if (next != NULL) {
2294 // Add to this manager's list of chunks in use.
2295 add_chunk(next, false);
2296 mem = next->allocate(word_size);
2297 }
2298
2299 // Track metaspace memory usage statistic.
2300 track_metaspace_memory_usage();
2301
2302 return mem;
2303 }
2304
2305 void SpaceManager::print_on(outputStream* st) const {
2306
2307 for (ChunkIndex i = ZeroIndex;
2308 i < NumberOfInUseLists ;
2309 i = next_chunk_index(i) ) {
2310 st->print_cr(" chunks_in_use " PTR_FORMAT " chunk size " SIZE_FORMAT,
2311 p2i(chunks_in_use(i)),
2312 chunks_in_use(i) == NULL ? 0 : chunks_in_use(i)->word_size());
2313 }
2314 st->print_cr(" waste: Small " SIZE_FORMAT " Medium " SIZE_FORMAT
2315 " Humongous " SIZE_FORMAT,
2316 sum_waste_in_chunks_in_use(SmallIndex),
2317 sum_waste_in_chunks_in_use(MediumIndex),
2318 sum_waste_in_chunks_in_use(HumongousIndex));
2319 // block free lists
2320 if (block_freelists() != NULL) {
2321 st->print_cr("total in block free lists " SIZE_FORMAT,
2322 block_freelists()->total_size());
2323 }
2324 }
2325
2326 SpaceManager::SpaceManager(Metaspace::MetadataType mdtype,
2327 Mutex* lock) :
2328 _mdtype(mdtype),
2329 _allocated_blocks_words(0),
2330 _allocated_chunks_words(0),
2331 _allocated_chunks_count(0),
2332 _block_freelists(NULL),
2333 _lock(lock)
2334 {
2335 initialize();
2336 }
2337
2338 void SpaceManager::inc_size_metrics(size_t words) {
2339 assert_lock_strong(SpaceManager::expand_lock());
2340 // Total of allocated Metachunks and allocated Metachunks count
2341 // for each SpaceManager
2342 _allocated_chunks_words = _allocated_chunks_words + words;
2343 _allocated_chunks_count++;
2344 // Global total of capacity in allocated Metachunks
2345 MetaspaceAux::inc_capacity(mdtype(), words);
2346 // Global total of allocated Metablocks.
2347 // used_words_slow() includes the overhead in each
2348 // Metachunk so include it in the used when the
2349 // Metachunk is first added (so only added once per
2350 // Metachunk).
2351 MetaspaceAux::inc_used(mdtype(), Metachunk::overhead());
2352 }
2353
2354 void SpaceManager::inc_used_metrics(size_t words) {
2355 // Add to the per SpaceManager total
2356 Atomic::add_ptr(words, &_allocated_blocks_words);
2357 // Add to the global total
2358 MetaspaceAux::inc_used(mdtype(), words);
2359 }
2360
2361 void SpaceManager::dec_total_from_size_metrics() {
2362 MetaspaceAux::dec_capacity(mdtype(), allocated_chunks_words());
2363 MetaspaceAux::dec_used(mdtype(), allocated_blocks_words());
2364 // Also deduct the overhead per Metachunk
2365 MetaspaceAux::dec_used(mdtype(), allocated_chunks_count() * Metachunk::overhead());
2366 }
2367
2368 void SpaceManager::initialize() {
2369 Metadebug::init_allocation_fail_alot_count();
2370 for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) {
2371 _chunks_in_use[i] = NULL;
2372 }
2373 _current_chunk = NULL;
2374 log_trace(gc, metaspace, freelist)("SpaceManager(): " PTR_FORMAT, p2i(this));
2375 }
2376
2377 SpaceManager::~SpaceManager() {
2378 // This call this->_lock which can't be done while holding expand_lock()
2379 assert(sum_capacity_in_chunks_in_use() == allocated_chunks_words(),
2380 "sum_capacity_in_chunks_in_use() " SIZE_FORMAT
2381 " allocated_chunks_words() " SIZE_FORMAT,
2382 sum_capacity_in_chunks_in_use(), allocated_chunks_words());
2383
2384 MutexLockerEx fcl(SpaceManager::expand_lock(),
2385 Mutex::_no_safepoint_check_flag);
2386
2387 chunk_manager()->slow_locked_verify();
2388
2389 dec_total_from_size_metrics();
2390
2391 Log(gc, metaspace, freelist) log;
2392 if (log.is_trace()) {
2393 log.trace("~SpaceManager(): " PTR_FORMAT, p2i(this));
2394 ResourceMark rm;
2395 locked_print_chunks_in_use_on(log.trace_stream());
2396 if (block_freelists() != NULL) {
2397 block_freelists()->print_on(log.trace_stream());
2398 }
2399 }
2400
2401 // Add all the chunks in use by this space manager
2402 // to the global list of free chunks.
2403
2404 // Follow each list of chunks-in-use and add them to the
2405 // free lists. Each list is NULL terminated.
2406
2407 for (ChunkIndex i = ZeroIndex; i <= HumongousIndex; i = next_chunk_index(i)) {
2408 Metachunk* chunks = chunks_in_use(i);
2409 chunk_manager()->return_chunk_list(i, chunks);
2410 set_chunks_in_use(i, NULL);
2411 }
2412
2413 chunk_manager()->slow_locked_verify();
2414
2415 if (_block_freelists != NULL) {
2416 delete _block_freelists;
2417 }
2418 }
2419
2420 void SpaceManager::deallocate(MetaWord* p, size_t word_size) {
2421 assert_lock_strong(_lock);
2422 // Allocations and deallocations are in raw_word_size
2423 size_t raw_word_size = get_allocation_word_size(word_size);
2424 // Lazily create a block_freelist
2425 if (block_freelists() == NULL) {
2426 _block_freelists = new BlockFreelist();
2427 }
2428 block_freelists()->return_block(p, raw_word_size);
2429 }
2430
2431 // Adds a chunk to the list of chunks in use.
2432 void SpaceManager::add_chunk(Metachunk* new_chunk, bool make_current) {
2433
2434 assert(new_chunk != NULL, "Should not be NULL");
2435 assert(new_chunk->next() == NULL, "Should not be on a list");
2436
2437 new_chunk->reset_empty();
2438
2439 // Find the correct list and and set the current
2440 // chunk for that list.
2441 ChunkIndex index = chunk_manager()->list_index(new_chunk->word_size());
2442
2443 if (index != HumongousIndex) {
2444 retire_current_chunk();
2445 set_current_chunk(new_chunk);
2446 new_chunk->set_next(chunks_in_use(index));
2447 set_chunks_in_use(index, new_chunk);
2448 } else {
2449 // For null class loader data and DumpSharedSpaces, the first chunk isn't
2450 // small, so small will be null. Link this first chunk as the current
2451 // chunk.
2452 if (make_current) {
2453 // Set as the current chunk but otherwise treat as a humongous chunk.
2454 set_current_chunk(new_chunk);
2455 }
2456 // Link at head. The _current_chunk only points to a humongous chunk for
2457 // the null class loader metaspace (class and data virtual space managers)
2458 // any humongous chunks so will not point to the tail
2459 // of the humongous chunks list.
2460 new_chunk->set_next(chunks_in_use(HumongousIndex));
2461 set_chunks_in_use(HumongousIndex, new_chunk);
2462
2463 assert(new_chunk->word_size() > medium_chunk_size(), "List inconsistency");
2464 }
2465
2466 // Add to the running sum of capacity
2467 inc_size_metrics(new_chunk->word_size());
2468
2469 assert(new_chunk->is_empty(), "Not ready for reuse");
2470 Log(gc, metaspace, freelist) log;
2471 if (log.is_trace()) {
2472 log.trace("SpaceManager::add_chunk: " SIZE_FORMAT ") ", sum_count_in_chunks_in_use());
2473 ResourceMark rm;
2474 outputStream* out = log.trace_stream();
2475 new_chunk->print_on(out);
2476 chunk_manager()->locked_print_free_chunks(out);
2477 }
2478 }
2479
2480 void SpaceManager::retire_current_chunk() {
2481 if (current_chunk() != NULL) {
2482 size_t remaining_words = current_chunk()->free_word_size();
2483 if (remaining_words >= BlockFreelist::min_dictionary_size()) {
2484 MetaWord* ptr = current_chunk()->allocate(remaining_words);
2485 deallocate(ptr, remaining_words);
2486 inc_used_metrics(remaining_words);
2487 }
2488 }
2489 }
2490
2491 Metachunk* SpaceManager::get_new_chunk(size_t chunk_word_size) {
2492 // Get a chunk from the chunk freelist
2493 Metachunk* next = chunk_manager()->chunk_freelist_allocate(chunk_word_size);
2494
2495 if (next == NULL) {
2496 next = vs_list()->get_new_chunk(chunk_word_size,
2497 medium_chunk_bunch());
2498 }
2499
2500 Log(gc, metaspace, alloc) log;
2501 if (log.is_debug() && next != NULL &&
2502 SpaceManager::is_humongous(next->word_size())) {
2503 log.debug(" new humongous chunk word size " PTR_FORMAT, next->word_size());
2504 }
2505
2506 return next;
2507 }
2508
2509 /*
2510 * The policy is to allocate up to _small_chunk_limit small chunks
2511 * after which only medium chunks are allocated. This is done to
2512 * reduce fragmentation. In some cases, this can result in a lot
2513 * of small chunks being allocated to the point where it's not
2514 * possible to expand. If this happens, there may be no medium chunks
2515 * available and OOME would be thrown. Instead of doing that,
2516 * if the allocation request size fits in a small chunk, an attempt
2517 * will be made to allocate a small chunk.
2518 */
2519 MetaWord* SpaceManager::get_small_chunk_and_allocate(size_t word_size) {
2520 size_t raw_word_size = get_allocation_word_size(word_size);
2521
2522 if (raw_word_size + Metachunk::overhead() > small_chunk_size()) {
2523 return NULL;
2524 }
2525
2526 MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag);
2527 MutexLockerEx cl1(expand_lock(), Mutex::_no_safepoint_check_flag);
2528
2529 Metachunk* chunk = chunk_manager()->chunk_freelist_allocate(small_chunk_size());
2530
2531 MetaWord* mem = NULL;
2532
2533 if (chunk != NULL) {
2534 // Add chunk to the in-use chunk list and do an allocation from it.
2535 // Add to this manager's list of chunks in use.
2536 add_chunk(chunk, false);
2537 mem = chunk->allocate(raw_word_size);
2538
2539 inc_used_metrics(raw_word_size);
2540
2541 // Track metaspace memory usage statistic.
2542 track_metaspace_memory_usage();
2543 }
2544
2545 return mem;
2546 }
2547
2548 MetaWord* SpaceManager::allocate(size_t word_size) {
2549 MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag);
2550 size_t raw_word_size = get_allocation_word_size(word_size);
2551 BlockFreelist* fl = block_freelists();
2552 MetaWord* p = NULL;
2553 // Allocation from the dictionary is expensive in the sense that
2554 // the dictionary has to be searched for a size. Don't allocate
2555 // from the dictionary until it starts to get fat. Is this
2556 // a reasonable policy? Maybe an skinny dictionary is fast enough
2557 // for allocations. Do some profiling. JJJ
2558 if (fl != NULL && fl->total_size() > allocation_from_dictionary_limit) {
2559 p = fl->get_block(raw_word_size);
2560 }
2561 if (p == NULL) {
2562 p = allocate_work(raw_word_size);
2563 }
2564
2565 return p;
2566 }
2567
2568 // Returns the address of spaced allocated for "word_size".
2569 // This methods does not know about blocks (Metablocks)
2570 MetaWord* SpaceManager::allocate_work(size_t word_size) {
2571 assert_lock_strong(_lock);
2572 #ifdef ASSERT
2573 if (Metadebug::test_metadata_failure()) {
2574 return NULL;
2575 }
2576 #endif
2577 // Is there space in the current chunk?
2578 MetaWord* result = NULL;
2579
2580 // For DumpSharedSpaces, only allocate out of the current chunk which is
2581 // never null because we gave it the size we wanted. Caller reports out
2582 // of memory if this returns null.
2583 if (DumpSharedSpaces) {
2584 assert(current_chunk() != NULL, "should never happen");
2585 inc_used_metrics(word_size);
2586 return current_chunk()->allocate(word_size); // caller handles null result
2587 }
2588
2589 if (current_chunk() != NULL) {
2590 result = current_chunk()->allocate(word_size);
2591 }
2592
2593 if (result == NULL) {
2594 result = grow_and_allocate(word_size);
2595 }
2596
2597 if (result != NULL) {
2598 inc_used_metrics(word_size);
2599 assert(result != (MetaWord*) chunks_in_use(MediumIndex),
2600 "Head of the list is being allocated");
2601 }
2602
2603 return result;
2604 }
2605
2606 void SpaceManager::verify() {
2607 // If there are blocks in the dictionary, then
2608 // verification of chunks does not work since
2609 // being in the dictionary alters a chunk.
2610 if (block_freelists() != NULL && block_freelists()->total_size() == 0) {
2611 for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) {
2612 Metachunk* curr = chunks_in_use(i);
2613 while (curr != NULL) {
2614 curr->verify();
2615 verify_chunk_size(curr);
2616 curr = curr->next();
2617 }
2618 }
2619 }
2620 }
2621
2622 void SpaceManager::verify_chunk_size(Metachunk* chunk) {
2623 assert(is_humongous(chunk->word_size()) ||
2624 chunk->word_size() == medium_chunk_size() ||
2625 chunk->word_size() == small_chunk_size() ||
2626 chunk->word_size() == specialized_chunk_size(),
2627 "Chunk size is wrong");
2628 return;
2629 }
2630
2631 #ifdef ASSERT
2632 void SpaceManager::verify_allocated_blocks_words() {
2633 // Verification is only guaranteed at a safepoint.
2634 assert(SafepointSynchronize::is_at_safepoint() || !Universe::is_fully_initialized(),
2635 "Verification can fail if the applications is running");
2636 assert(allocated_blocks_words() == sum_used_in_chunks_in_use(),
2637 "allocation total is not consistent " SIZE_FORMAT
2638 " vs " SIZE_FORMAT,
2639 allocated_blocks_words(), sum_used_in_chunks_in_use());
2640 }
2641
2642 #endif
2643
2644 void SpaceManager::dump(outputStream* const out) const {
2645 size_t curr_total = 0;
2646 size_t waste = 0;
2647 uint i = 0;
2648 size_t used = 0;
2649 size_t capacity = 0;
2650
2651 // Add up statistics for all chunks in this SpaceManager.
2652 for (ChunkIndex index = ZeroIndex;
2653 index < NumberOfInUseLists;
2654 index = next_chunk_index(index)) {
2655 for (Metachunk* curr = chunks_in_use(index);
2656 curr != NULL;
2657 curr = curr->next()) {
2658 out->print("%d) ", i++);
2659 curr->print_on(out);
2660 curr_total += curr->word_size();
2661 used += curr->used_word_size();
2662 capacity += curr->word_size();
2663 waste += curr->free_word_size() + curr->overhead();;
2664 }
2665 }
2666
2667 if (log_is_enabled(Trace, gc, metaspace, freelist)) {
2668 if (block_freelists() != NULL) block_freelists()->print_on(out);
2669 }
2670
2671 size_t free = current_chunk() == NULL ? 0 : current_chunk()->free_word_size();
2672 // Free space isn't wasted.
2673 waste -= free;
2674
2675 out->print_cr("total of all chunks " SIZE_FORMAT " used " SIZE_FORMAT
2676 " free " SIZE_FORMAT " capacity " SIZE_FORMAT
2677 " waste " SIZE_FORMAT, curr_total, used, free, capacity, waste);
2678 }
2679
2680 // MetaspaceAux
2681
2682
2683 size_t MetaspaceAux::_capacity_words[] = {0, 0};
2684 size_t MetaspaceAux::_used_words[] = {0, 0};
2685
2686 size_t MetaspaceAux::free_bytes(Metaspace::MetadataType mdtype) {
2687 VirtualSpaceList* list = Metaspace::get_space_list(mdtype);
2688 return list == NULL ? 0 : list->free_bytes();
2689 }
2690
2691 size_t MetaspaceAux::free_bytes() {
2692 return free_bytes(Metaspace::ClassType) + free_bytes(Metaspace::NonClassType);
2693 }
2694
2695 void MetaspaceAux::dec_capacity(Metaspace::MetadataType mdtype, size_t words) {
2696 assert_lock_strong(SpaceManager::expand_lock());
2697 assert(words <= capacity_words(mdtype),
2698 "About to decrement below 0: words " SIZE_FORMAT
2699 " is greater than _capacity_words[%u] " SIZE_FORMAT,
2700 words, mdtype, capacity_words(mdtype));
2701 _capacity_words[mdtype] -= words;
2702 }
2703
2704 void MetaspaceAux::inc_capacity(Metaspace::MetadataType mdtype, size_t words) {
2705 assert_lock_strong(SpaceManager::expand_lock());
2706 // Needs to be atomic
2707 _capacity_words[mdtype] += words;
2708 }
2709
2710 void MetaspaceAux::dec_used(Metaspace::MetadataType mdtype, size_t words) {
2711 assert(words <= used_words(mdtype),
2712 "About to decrement below 0: words " SIZE_FORMAT
2713 " is greater than _used_words[%u] " SIZE_FORMAT,
2714 words, mdtype, used_words(mdtype));
2715 // For CMS deallocation of the Metaspaces occurs during the
2716 // sweep which is a concurrent phase. Protection by the expand_lock()
2717 // is not enough since allocation is on a per Metaspace basis
2718 // and protected by the Metaspace lock.
2719 jlong minus_words = (jlong) - (jlong) words;
2720 Atomic::add_ptr(minus_words, &_used_words[mdtype]);
2721 }
2722
2723 void MetaspaceAux::inc_used(Metaspace::MetadataType mdtype, size_t words) {
2724 // _used_words tracks allocations for
2725 // each piece of metadata. Those allocations are
2726 // generally done concurrently by different application
2727 // threads so must be done atomically.
2728 Atomic::add_ptr(words, &_used_words[mdtype]);
2729 }
2730
2731 size_t MetaspaceAux::used_bytes_slow(Metaspace::MetadataType mdtype) {
2732 size_t used = 0;
2733 ClassLoaderDataGraphMetaspaceIterator iter;
2734 while (iter.repeat()) {
2735 Metaspace* msp = iter.get_next();
2736 // Sum allocated_blocks_words for each metaspace
2737 if (msp != NULL) {
2738 used += msp->used_words_slow(mdtype);
2739 }
2740 }
2741 return used * BytesPerWord;
2742 }
2743
2744 size_t MetaspaceAux::free_bytes_slow(Metaspace::MetadataType mdtype) {
2745 size_t free = 0;
2746 ClassLoaderDataGraphMetaspaceIterator iter;
2747 while (iter.repeat()) {
2748 Metaspace* msp = iter.get_next();
2749 if (msp != NULL) {
2750 free += msp->free_words_slow(mdtype);
2751 }
2752 }
2753 return free * BytesPerWord;
2754 }
2755
2756 size_t MetaspaceAux::capacity_bytes_slow(Metaspace::MetadataType mdtype) {
2757 if ((mdtype == Metaspace::ClassType) && !Metaspace::using_class_space()) {
2758 return 0;
2759 }
2760 // Don't count the space in the freelists. That space will be
2761 // added to the capacity calculation as needed.
2762 size_t capacity = 0;
2763 ClassLoaderDataGraphMetaspaceIterator iter;
2764 while (iter.repeat()) {
2765 Metaspace* msp = iter.get_next();
2766 if (msp != NULL) {
2767 capacity += msp->capacity_words_slow(mdtype);
2768 }
2769 }
2770 return capacity * BytesPerWord;
2771 }
2772
2773 size_t MetaspaceAux::capacity_bytes_slow() {
2774 #ifdef PRODUCT
2775 // Use capacity_bytes() in PRODUCT instead of this function.
2776 guarantee(false, "Should not call capacity_bytes_slow() in the PRODUCT");
2777 #endif
2778 size_t class_capacity = capacity_bytes_slow(Metaspace::ClassType);
2779 size_t non_class_capacity = capacity_bytes_slow(Metaspace::NonClassType);
2780 assert(capacity_bytes() == class_capacity + non_class_capacity,
2781 "bad accounting: capacity_bytes() " SIZE_FORMAT
2782 " class_capacity + non_class_capacity " SIZE_FORMAT
2783 " class_capacity " SIZE_FORMAT " non_class_capacity " SIZE_FORMAT,
2784 capacity_bytes(), class_capacity + non_class_capacity,
2785 class_capacity, non_class_capacity);
2786
2787 return class_capacity + non_class_capacity;
2788 }
2789
2790 size_t MetaspaceAux::reserved_bytes(Metaspace::MetadataType mdtype) {
2791 VirtualSpaceList* list = Metaspace::get_space_list(mdtype);
2792 return list == NULL ? 0 : list->reserved_bytes();
2793 }
2794
2795 size_t MetaspaceAux::committed_bytes(Metaspace::MetadataType mdtype) {
2796 VirtualSpaceList* list = Metaspace::get_space_list(mdtype);
2797 return list == NULL ? 0 : list->committed_bytes();
2798 }
2799
2800 size_t MetaspaceAux::min_chunk_size_words() { return Metaspace::first_chunk_word_size(); }
2801
2802 size_t MetaspaceAux::free_chunks_total_words(Metaspace::MetadataType mdtype) {
2803 ChunkManager* chunk_manager = Metaspace::get_chunk_manager(mdtype);
2804 if (chunk_manager == NULL) {
2805 return 0;
2806 }
2807 chunk_manager->slow_verify();
2808 return chunk_manager->free_chunks_total_words();
2809 }
2810
2811 size_t MetaspaceAux::free_chunks_total_bytes(Metaspace::MetadataType mdtype) {
2812 return free_chunks_total_words(mdtype) * BytesPerWord;
2813 }
2814
2815 size_t MetaspaceAux::free_chunks_total_words() {
2816 return free_chunks_total_words(Metaspace::ClassType) +
2817 free_chunks_total_words(Metaspace::NonClassType);
2818 }
2819
2820 size_t MetaspaceAux::free_chunks_total_bytes() {
2821 return free_chunks_total_words() * BytesPerWord;
2822 }
2823
2824 bool MetaspaceAux::has_chunk_free_list(Metaspace::MetadataType mdtype) {
2825 return Metaspace::get_chunk_manager(mdtype) != NULL;
2826 }
2827
2828 MetaspaceChunkFreeListSummary MetaspaceAux::chunk_free_list_summary(Metaspace::MetadataType mdtype) {
2829 if (!has_chunk_free_list(mdtype)) {
2830 return MetaspaceChunkFreeListSummary();
2831 }
2832
2833 const ChunkManager* cm = Metaspace::get_chunk_manager(mdtype);
2834 return cm->chunk_free_list_summary();
2835 }
2836
2837 void MetaspaceAux::print_metaspace_change(size_t prev_metadata_used) {
2838 log_info(gc, metaspace)("Metaspace: " SIZE_FORMAT "K->" SIZE_FORMAT "K(" SIZE_FORMAT "K)",
2839 prev_metadata_used/K, used_bytes()/K, reserved_bytes()/K);
2840 }
2841
2842 void MetaspaceAux::print_on(outputStream* out) {
2843 Metaspace::MetadataType nct = Metaspace::NonClassType;
2844
2845 out->print_cr(" Metaspace "
2846 "used " SIZE_FORMAT "K, "
2847 "capacity " SIZE_FORMAT "K, "
2848 "committed " SIZE_FORMAT "K, "
2849 "reserved " SIZE_FORMAT "K",
2850 used_bytes()/K,
2851 capacity_bytes()/K,
2852 committed_bytes()/K,
2853 reserved_bytes()/K);
2854
2855 if (Metaspace::using_class_space()) {
2856 Metaspace::MetadataType ct = Metaspace::ClassType;
2857 out->print_cr(" class space "
2858 "used " SIZE_FORMAT "K, "
2859 "capacity " SIZE_FORMAT "K, "
2860 "committed " SIZE_FORMAT "K, "
2861 "reserved " SIZE_FORMAT "K",
2862 used_bytes(ct)/K,
2863 capacity_bytes(ct)/K,
2864 committed_bytes(ct)/K,
2865 reserved_bytes(ct)/K);
2866 }
2867 }
2868
2869 // Print information for class space and data space separately.
2870 // This is almost the same as above.
2871 void MetaspaceAux::print_on(outputStream* out, Metaspace::MetadataType mdtype) {
2872 size_t free_chunks_capacity_bytes = free_chunks_total_bytes(mdtype);
2873 size_t capacity_bytes = capacity_bytes_slow(mdtype);
2874 size_t used_bytes = used_bytes_slow(mdtype);
2875 size_t free_bytes = free_bytes_slow(mdtype);
2876 size_t used_and_free = used_bytes + free_bytes +
2877 free_chunks_capacity_bytes;
2878 out->print_cr(" Chunk accounting: used in chunks " SIZE_FORMAT
2879 "K + unused in chunks " SIZE_FORMAT "K + "
2880 " capacity in free chunks " SIZE_FORMAT "K = " SIZE_FORMAT
2881 "K capacity in allocated chunks " SIZE_FORMAT "K",
2882 used_bytes / K,
2883 free_bytes / K,
2884 free_chunks_capacity_bytes / K,
2885 used_and_free / K,
2886 capacity_bytes / K);
2887 // Accounting can only be correct if we got the values during a safepoint
2888 assert(!SafepointSynchronize::is_at_safepoint() || used_and_free == capacity_bytes, "Accounting is wrong");
2889 }
2890
2891 // Print total fragmentation for class metaspaces
2892 void MetaspaceAux::print_class_waste(outputStream* out) {
2893 assert(Metaspace::using_class_space(), "class metaspace not used");
2894 size_t cls_specialized_waste = 0, cls_small_waste = 0, cls_medium_waste = 0;
2895 size_t cls_specialized_count = 0, cls_small_count = 0, cls_medium_count = 0, cls_humongous_count = 0;
2896 ClassLoaderDataGraphMetaspaceIterator iter;
2897 while (iter.repeat()) {
2898 Metaspace* msp = iter.get_next();
2899 if (msp != NULL) {
2900 cls_specialized_waste += msp->class_vsm()->sum_waste_in_chunks_in_use(SpecializedIndex);
2901 cls_specialized_count += msp->class_vsm()->sum_count_in_chunks_in_use(SpecializedIndex);
2902 cls_small_waste += msp->class_vsm()->sum_waste_in_chunks_in_use(SmallIndex);
2903 cls_small_count += msp->class_vsm()->sum_count_in_chunks_in_use(SmallIndex);
2904 cls_medium_waste += msp->class_vsm()->sum_waste_in_chunks_in_use(MediumIndex);
2905 cls_medium_count += msp->class_vsm()->sum_count_in_chunks_in_use(MediumIndex);
2906 cls_humongous_count += msp->class_vsm()->sum_count_in_chunks_in_use(HumongousIndex);
2907 }
2908 }
2909 out->print_cr(" class: " SIZE_FORMAT " specialized(s) " SIZE_FORMAT ", "
2910 SIZE_FORMAT " small(s) " SIZE_FORMAT ", "
2911 SIZE_FORMAT " medium(s) " SIZE_FORMAT ", "
2912 "large count " SIZE_FORMAT,
2913 cls_specialized_count, cls_specialized_waste,
2914 cls_small_count, cls_small_waste,
2915 cls_medium_count, cls_medium_waste, cls_humongous_count);
2916 }
2917
2918 // Print total fragmentation for data and class metaspaces separately
2919 void MetaspaceAux::print_waste(outputStream* out) {
2920 size_t specialized_waste = 0, small_waste = 0, medium_waste = 0;
2921 size_t specialized_count = 0, small_count = 0, medium_count = 0, humongous_count = 0;
2922
2923 ClassLoaderDataGraphMetaspaceIterator iter;
2924 while (iter.repeat()) {
2925 Metaspace* msp = iter.get_next();
2926 if (msp != NULL) {
2927 specialized_waste += msp->vsm()->sum_waste_in_chunks_in_use(SpecializedIndex);
2928 specialized_count += msp->vsm()->sum_count_in_chunks_in_use(SpecializedIndex);
2929 small_waste += msp->vsm()->sum_waste_in_chunks_in_use(SmallIndex);
2930 small_count += msp->vsm()->sum_count_in_chunks_in_use(SmallIndex);
2931 medium_waste += msp->vsm()->sum_waste_in_chunks_in_use(MediumIndex);
2932 medium_count += msp->vsm()->sum_count_in_chunks_in_use(MediumIndex);
2933 humongous_count += msp->vsm()->sum_count_in_chunks_in_use(HumongousIndex);
2934 }
2935 }
2936 out->print_cr("Total fragmentation waste (words) doesn't count free space");
2937 out->print_cr(" data: " SIZE_FORMAT " specialized(s) " SIZE_FORMAT ", "
2938 SIZE_FORMAT " small(s) " SIZE_FORMAT ", "
2939 SIZE_FORMAT " medium(s) " SIZE_FORMAT ", "
2940 "large count " SIZE_FORMAT,
2941 specialized_count, specialized_waste, small_count,
2942 small_waste, medium_count, medium_waste, humongous_count);
2943 if (Metaspace::using_class_space()) {
2944 print_class_waste(out);
2945 }
2946 }
2947
2948 // Dump global metaspace things from the end of ClassLoaderDataGraph
2949 void MetaspaceAux::dump(outputStream* out) {
2950 out->print_cr("All Metaspace:");
2951 out->print("data space: "); print_on(out, Metaspace::NonClassType);
2952 out->print("class space: "); print_on(out, Metaspace::ClassType);
2953 print_waste(out);
2954 }
2955
2956 void MetaspaceAux::verify_free_chunks() {
2957 Metaspace::chunk_manager_metadata()->verify();
2958 if (Metaspace::using_class_space()) {
2959 Metaspace::chunk_manager_class()->verify();
2960 }
2961 }
2962
2963 void MetaspaceAux::verify_capacity() {
2964 #ifdef ASSERT
2965 size_t running_sum_capacity_bytes = capacity_bytes();
2966 // For purposes of the running sum of capacity, verify against capacity
2967 size_t capacity_in_use_bytes = capacity_bytes_slow();
2968 assert(running_sum_capacity_bytes == capacity_in_use_bytes,
2969 "capacity_words() * BytesPerWord " SIZE_FORMAT
2970 " capacity_bytes_slow()" SIZE_FORMAT,
2971 running_sum_capacity_bytes, capacity_in_use_bytes);
2972 for (Metaspace::MetadataType i = Metaspace::ClassType;
2973 i < Metaspace:: MetadataTypeCount;
2974 i = (Metaspace::MetadataType)(i + 1)) {
2975 size_t capacity_in_use_bytes = capacity_bytes_slow(i);
2976 assert(capacity_bytes(i) == capacity_in_use_bytes,
2977 "capacity_bytes(%u) " SIZE_FORMAT
2978 " capacity_bytes_slow(%u)" SIZE_FORMAT,
2979 i, capacity_bytes(i), i, capacity_in_use_bytes);
2980 }
2981 #endif
2982 }
2983
2984 void MetaspaceAux::verify_used() {
2985 #ifdef ASSERT
2986 size_t running_sum_used_bytes = used_bytes();
2987 // For purposes of the running sum of used, verify against used
2988 size_t used_in_use_bytes = used_bytes_slow();
2989 assert(used_bytes() == used_in_use_bytes,
2990 "used_bytes() " SIZE_FORMAT
2991 " used_bytes_slow()" SIZE_FORMAT,
2992 used_bytes(), used_in_use_bytes);
2993 for (Metaspace::MetadataType i = Metaspace::ClassType;
2994 i < Metaspace:: MetadataTypeCount;
2995 i = (Metaspace::MetadataType)(i + 1)) {
2996 size_t used_in_use_bytes = used_bytes_slow(i);
2997 assert(used_bytes(i) == used_in_use_bytes,
2998 "used_bytes(%u) " SIZE_FORMAT
2999 " used_bytes_slow(%u)" SIZE_FORMAT,
3000 i, used_bytes(i), i, used_in_use_bytes);
3001 }
3002 #endif
3003 }
3004
3005 void MetaspaceAux::verify_metrics() {
3006 verify_capacity();
3007 verify_used();
3008 }
3009
3010
3011 // Metaspace methods
3012
3013 size_t Metaspace::_first_chunk_word_size = 0;
3014 size_t Metaspace::_first_class_chunk_word_size = 0;
3015
3016 size_t Metaspace::_commit_alignment = 0;
3017 size_t Metaspace::_reserve_alignment = 0;
3018
3019 Metaspace::Metaspace(Mutex* lock, MetaspaceType type) {
3020 initialize(lock, type);
3021 }
3022
3023 Metaspace::~Metaspace() {
3024 delete _vsm;
3025 if (using_class_space()) {
3026 delete _class_vsm;
3027 }
3028 }
3029
3030 VirtualSpaceList* Metaspace::_space_list = NULL;
3031 VirtualSpaceList* Metaspace::_class_space_list = NULL;
3032
3033 ChunkManager* Metaspace::_chunk_manager_metadata = NULL;
3034 ChunkManager* Metaspace::_chunk_manager_class = NULL;
3035
3036 #define VIRTUALSPACEMULTIPLIER 2
3037
3038 #ifdef _LP64
3039 static const uint64_t UnscaledClassSpaceMax = (uint64_t(max_juint) + 1);
3040
3041 void Metaspace::set_narrow_klass_base_and_shift(address metaspace_base, address cds_base) {
3042 // Figure out the narrow_klass_base and the narrow_klass_shift. The
3043 // narrow_klass_base is the lower of the metaspace base and the cds base
3044 // (if cds is enabled). The narrow_klass_shift depends on the distance
3045 // between the lower base and higher address.
3046 address lower_base;
3047 address higher_address;
3048 #if INCLUDE_CDS
3049 if (UseSharedSpaces) {
3050 higher_address = MAX2((address)(cds_base + FileMapInfo::shared_spaces_size()),
3051 (address)(metaspace_base + compressed_class_space_size()));
3052 lower_base = MIN2(metaspace_base, cds_base);
3053 } else
3054 #endif
3055 {
3056 higher_address = metaspace_base + compressed_class_space_size();
3057 lower_base = metaspace_base;
3058
3059 uint64_t klass_encoding_max = UnscaledClassSpaceMax << LogKlassAlignmentInBytes;
3060 // If compressed class space fits in lower 32G, we don't need a base.
3061 if (higher_address <= (address)klass_encoding_max) {
3062 lower_base = 0; // Effectively lower base is zero.
3063 }
3064 }
3065
3066 Universe::set_narrow_klass_base(lower_base);
3067
3068 if ((uint64_t)(higher_address - lower_base) <= UnscaledClassSpaceMax) {
3069 Universe::set_narrow_klass_shift(0);
3070 } else {
3071 assert(!UseSharedSpaces, "Cannot shift with UseSharedSpaces");
3072 Universe::set_narrow_klass_shift(LogKlassAlignmentInBytes);
3073 }
3074 AOTLoader::set_narrow_klass_shift();
3075 }
3076
3077 #if INCLUDE_CDS
3078 // Return TRUE if the specified metaspace_base and cds_base are close enough
3079 // to work with compressed klass pointers.
3080 bool Metaspace::can_use_cds_with_metaspace_addr(char* metaspace_base, address cds_base) {
3081 assert(cds_base != 0 && UseSharedSpaces, "Only use with CDS");
3082 assert(UseCompressedClassPointers, "Only use with CompressedKlassPtrs");
3083 address lower_base = MIN2((address)metaspace_base, cds_base);
3084 address higher_address = MAX2((address)(cds_base + FileMapInfo::shared_spaces_size()),
3085 (address)(metaspace_base + compressed_class_space_size()));
3086 return ((uint64_t)(higher_address - lower_base) <= UnscaledClassSpaceMax);
3087 }
3088 #endif
3089
3090 // Try to allocate the metaspace at the requested addr.
3091 void Metaspace::allocate_metaspace_compressed_klass_ptrs(char* requested_addr, address cds_base) {
3092 assert(using_class_space(), "called improperly");
3093 assert(UseCompressedClassPointers, "Only use with CompressedKlassPtrs");
3094 assert(compressed_class_space_size() < KlassEncodingMetaspaceMax,
3095 "Metaspace size is too big");
3096 assert_is_aligned(requested_addr, _reserve_alignment);
3097 assert_is_aligned(cds_base, _reserve_alignment);
3098 assert_is_aligned(compressed_class_space_size(), _reserve_alignment);
3099
3100 // Don't use large pages for the class space.
3101 bool large_pages = false;
3102
3103 #if !(defined(AARCH64) || defined(AIX))
3104 ReservedSpace metaspace_rs = ReservedSpace(compressed_class_space_size(),
3105 _reserve_alignment,
3106 large_pages,
3107 requested_addr);
3108 #else // AARCH64
3109 ReservedSpace metaspace_rs;
3110
3111 // Our compressed klass pointers may fit nicely into the lower 32
3112 // bits.
3113 if ((uint64_t)requested_addr + compressed_class_space_size() < 4*G) {
3114 metaspace_rs = ReservedSpace(compressed_class_space_size(),
3115 _reserve_alignment,
3116 large_pages,
3117 requested_addr);
3118 }
3119
3120 if (! metaspace_rs.is_reserved()) {
3121 // Aarch64: Try to align metaspace so that we can decode a compressed
3122 // klass with a single MOVK instruction. We can do this iff the
3123 // compressed class base is a multiple of 4G.
3124 // Aix: Search for a place where we can find memory. If we need to load
3125 // the base, 4G alignment is helpful, too.
3126 size_t increment = AARCH64_ONLY(4*)G;
3127 for (char *a = align_up(requested_addr, increment);
3128 a < (char*)(1024*G);
3129 a += increment) {
3130 if (a == (char *)(32*G)) {
3131 // Go faster from here on. Zero-based is no longer possible.
3132 increment = 4*G;
3133 }
3134
3135 #if INCLUDE_CDS
3136 if (UseSharedSpaces
3137 && ! can_use_cds_with_metaspace_addr(a, cds_base)) {
3138 // We failed to find an aligned base that will reach. Fall
3139 // back to using our requested addr.
3140 metaspace_rs = ReservedSpace(compressed_class_space_size(),
3141 _reserve_alignment,
3142 large_pages,
3143 requested_addr);
3144 break;
3145 }
3146 #endif
3147
3148 metaspace_rs = ReservedSpace(compressed_class_space_size(),
3149 _reserve_alignment,
3150 large_pages,
3151 a);
3152 if (metaspace_rs.is_reserved())
3153 break;
3154 }
3155 }
3156
3157 #endif // AARCH64
3158
3159 if (!metaspace_rs.is_reserved()) {
3160 #if INCLUDE_CDS
3161 if (UseSharedSpaces) {
3162 size_t increment = align_up(1*G, _reserve_alignment);
3163
3164 // Keep trying to allocate the metaspace, increasing the requested_addr
3165 // by 1GB each time, until we reach an address that will no longer allow
3166 // use of CDS with compressed klass pointers.
3167 char *addr = requested_addr;
3168 while (!metaspace_rs.is_reserved() && (addr + increment > addr) &&
3169 can_use_cds_with_metaspace_addr(addr + increment, cds_base)) {
3170 addr = addr + increment;
3171 metaspace_rs = ReservedSpace(compressed_class_space_size(),
3172 _reserve_alignment, large_pages, addr);
3173 }
3174 }
3175 #endif
3176 // If no successful allocation then try to allocate the space anywhere. If
3177 // that fails then OOM doom. At this point we cannot try allocating the
3178 // metaspace as if UseCompressedClassPointers is off because too much
3179 // initialization has happened that depends on UseCompressedClassPointers.
3180 // So, UseCompressedClassPointers cannot be turned off at this point.
3181 if (!metaspace_rs.is_reserved()) {
3182 metaspace_rs = ReservedSpace(compressed_class_space_size(),
3183 _reserve_alignment, large_pages);
3184 if (!metaspace_rs.is_reserved()) {
3185 vm_exit_during_initialization(err_msg("Could not allocate metaspace: " SIZE_FORMAT " bytes",
3186 compressed_class_space_size()));
3187 }
3188 }
3189 }
3190
3191 // If we got here then the metaspace got allocated.
3192 MemTracker::record_virtual_memory_type((address)metaspace_rs.base(), mtClass);
3193
3194 #if INCLUDE_CDS
3195 // Verify that we can use shared spaces. Otherwise, turn off CDS.
3196 if (UseSharedSpaces && !can_use_cds_with_metaspace_addr(metaspace_rs.base(), cds_base)) {
3197 FileMapInfo::stop_sharing_and_unmap(
3198 "Could not allocate metaspace at a compatible address");
3199 }
3200 #endif
3201 set_narrow_klass_base_and_shift((address)metaspace_rs.base(),
3202 UseSharedSpaces ? (address)cds_base : 0);
3203
3204 initialize_class_space(metaspace_rs);
3205
3206 if (log_is_enabled(Trace, gc, metaspace)) {
3207 Log(gc, metaspace) log;
3208 ResourceMark rm;
3209 print_compressed_class_space(log.trace_stream(), requested_addr);
3210 }
3211 }
3212
3213 void Metaspace::print_compressed_class_space(outputStream* st, const char* requested_addr) {
3214 st->print_cr("Narrow klass base: " PTR_FORMAT ", Narrow klass shift: %d",
3215 p2i(Universe::narrow_klass_base()), Universe::narrow_klass_shift());
3216 if (_class_space_list != NULL) {
3217 address base = (address)_class_space_list->current_virtual_space()->bottom();
3218 st->print("Compressed class space size: " SIZE_FORMAT " Address: " PTR_FORMAT,
3219 compressed_class_space_size(), p2i(base));
3220 if (requested_addr != 0) {
3221 st->print(" Req Addr: " PTR_FORMAT, p2i(requested_addr));
3222 }
3223 st->cr();
3224 }
3225 }
3226
3227 // For UseCompressedClassPointers the class space is reserved above the top of
3228 // the Java heap. The argument passed in is at the base of the compressed space.
3229 void Metaspace::initialize_class_space(ReservedSpace rs) {
3230 // The reserved space size may be bigger because of alignment, esp with UseLargePages
3231 assert(rs.size() >= CompressedClassSpaceSize,
3232 SIZE_FORMAT " != " SIZE_FORMAT, rs.size(), CompressedClassSpaceSize);
3233 assert(using_class_space(), "Must be using class space");
3234 _class_space_list = new VirtualSpaceList(rs);
3235 _chunk_manager_class = new ChunkManager(ClassSpecializedChunk, ClassSmallChunk, ClassMediumChunk);
3236
3237 if (!_class_space_list->initialization_succeeded()) {
3238 vm_exit_during_initialization("Failed to setup compressed class space virtual space list.");
3239 }
3240 }
3241
3242 #endif
3243
3244 void Metaspace::ergo_initialize() {
3245 if (DumpSharedSpaces) {
3246 // Using large pages when dumping the shared archive is currently not implemented.
3247 FLAG_SET_ERGO(bool, UseLargePagesInMetaspace, false);
3248 }
3249
3250 size_t page_size = os::vm_page_size();
3251 if (UseLargePages && UseLargePagesInMetaspace) {
3252 page_size = os::large_page_size();
3253 }
3254
3255 _commit_alignment = page_size;
3256 _reserve_alignment = MAX2(page_size, (size_t)os::vm_allocation_granularity());
3257
3258 // Do not use FLAG_SET_ERGO to update MaxMetaspaceSize, since this will
3259 // override if MaxMetaspaceSize was set on the command line or not.
3260 // This information is needed later to conform to the specification of the
3261 // java.lang.management.MemoryUsage API.
3262 //
3263 // Ideally, we would be able to set the default value of MaxMetaspaceSize in
3264 // globals.hpp to the aligned value, but this is not possible, since the
3265 // alignment depends on other flags being parsed.
3266 MaxMetaspaceSize = align_down_bounded(MaxMetaspaceSize, _reserve_alignment);
3267
3268 if (MetaspaceSize > MaxMetaspaceSize) {
3269 MetaspaceSize = MaxMetaspaceSize;
3270 }
3271
3272 MetaspaceSize = align_down_bounded(MetaspaceSize, _commit_alignment);
3273
3274 assert(MetaspaceSize <= MaxMetaspaceSize, "MetaspaceSize should be limited by MaxMetaspaceSize");
3275
3276 MinMetaspaceExpansion = align_down_bounded(MinMetaspaceExpansion, _commit_alignment);
3277 MaxMetaspaceExpansion = align_down_bounded(MaxMetaspaceExpansion, _commit_alignment);
3278
3279 CompressedClassSpaceSize = align_down_bounded(CompressedClassSpaceSize, _reserve_alignment);
3280 set_compressed_class_space_size(CompressedClassSpaceSize);
3281 }
3282
3283 void Metaspace::global_initialize() {
3284 MetaspaceGC::initialize();
3285
3286 // Initialize the alignment for shared spaces.
3287 int max_alignment = os::vm_allocation_granularity();
3288 size_t cds_total = 0;
3289
3290 MetaspaceShared::set_max_alignment(max_alignment);
3291
3292 if (DumpSharedSpaces) {
3293 #if INCLUDE_CDS
3294 MetaspaceShared::estimate_regions_size();
3295
3296 SharedReadOnlySize = align_up(SharedReadOnlySize, max_alignment);
3297 SharedReadWriteSize = align_up(SharedReadWriteSize, max_alignment);
3298 SharedMiscDataSize = align_up(SharedMiscDataSize, max_alignment);
3299 SharedMiscCodeSize = align_up(SharedMiscCodeSize, max_alignment);
3300
3301 // Initialize with the sum of the shared space sizes. The read-only
3302 // and read write metaspace chunks will be allocated out of this and the
3303 // remainder is the misc code and data chunks.
3304 cds_total = FileMapInfo::shared_spaces_size();
3305 cds_total = align_up(cds_total, _reserve_alignment);
3306 _space_list = new VirtualSpaceList(cds_total/wordSize);
3307 _chunk_manager_metadata = new ChunkManager(SpecializedChunk, SmallChunk, MediumChunk);
3308
3309 if (!_space_list->initialization_succeeded()) {
3310 vm_exit_during_initialization("Unable to dump shared archive.", NULL);
3311 }
3312
3313 #ifdef _LP64
3314 if (cds_total + compressed_class_space_size() > UnscaledClassSpaceMax) {
3315 vm_exit_during_initialization("Unable to dump shared archive.",
3316 err_msg("Size of archive (" SIZE_FORMAT ") + compressed class space ("
3317 SIZE_FORMAT ") == total (" SIZE_FORMAT ") is larger than compressed "
3318 "klass limit: " UINT64_FORMAT, cds_total, compressed_class_space_size(),
3319 cds_total + compressed_class_space_size(), UnscaledClassSpaceMax));
3320 }
3321
3322 // Set the compressed klass pointer base so that decoding of these pointers works
3323 // properly when creating the shared archive.
3324 assert(UseCompressedOops && UseCompressedClassPointers,
3325 "UseCompressedOops and UseCompressedClassPointers must be set");
3326 Universe::set_narrow_klass_base((address)_space_list->current_virtual_space()->bottom());
3327 log_develop_trace(gc, metaspace)("Setting_narrow_klass_base to Address: " PTR_FORMAT,
3328 p2i(_space_list->current_virtual_space()->bottom()));
3329
3330 Universe::set_narrow_klass_shift(0);
3331 #endif // _LP64
3332 #endif // INCLUDE_CDS
3333 } else {
3334 #if INCLUDE_CDS
3335 if (UseSharedSpaces) {
3336 // If using shared space, open the file that contains the shared space
3337 // and map in the memory before initializing the rest of metaspace (so
3338 // the addresses don't conflict)
3339 address cds_address = NULL;
3340 FileMapInfo* mapinfo = new FileMapInfo();
3341
3342 // Open the shared archive file, read and validate the header. If
3343 // initialization fails, shared spaces [UseSharedSpaces] are
3344 // disabled and the file is closed.
3345 // Map in spaces now also
3346 if (mapinfo->initialize() && MetaspaceShared::map_shared_spaces(mapinfo)) {
3347 cds_total = FileMapInfo::shared_spaces_size();
3348 cds_address = (address)mapinfo->header()->region_addr(0);
3349 #ifdef _LP64
3350 if (using_class_space()) {
3351 char* cds_end = (char*)(cds_address + cds_total);
3352 cds_end = align_up(cds_end, _reserve_alignment);
3353 // If UseCompressedClassPointers is set then allocate the metaspace area
3354 // above the heap and above the CDS area (if it exists).
3355 allocate_metaspace_compressed_klass_ptrs(cds_end, cds_address);
3356 // Map the shared string space after compressed pointers
3357 // because it relies on compressed class pointers setting to work
3358 mapinfo->map_string_regions();
3359 }
3360 #endif // _LP64
3361 } else {
3362 assert(!mapinfo->is_open() && !UseSharedSpaces,
3363 "archive file not closed or shared spaces not disabled.");
3364 }
3365 }
3366 #endif // INCLUDE_CDS
3367
3368 #ifdef _LP64
3369 if (!UseSharedSpaces && using_class_space()) {
3370 char* base = (char*)align_up(Universe::heap()->reserved_region().end(), _reserve_alignment);
3371 allocate_metaspace_compressed_klass_ptrs(base, 0);
3372 }
3373 #endif // _LP64
3374
3375 // Initialize these before initializing the VirtualSpaceList
3376 _first_chunk_word_size = InitialBootClassLoaderMetaspaceSize / BytesPerWord;
3377 _first_chunk_word_size = align_word_size_up(_first_chunk_word_size);
3378 // Make the first class chunk bigger than a medium chunk so it's not put
3379 // on the medium chunk list. The next chunk will be small and progress
3380 // from there. This size calculated by -version.
3381 _first_class_chunk_word_size = MIN2((size_t)MediumChunk*6,
3382 (CompressedClassSpaceSize/BytesPerWord)*2);
3383 _first_class_chunk_word_size = align_word_size_up(_first_class_chunk_word_size);
3384 // Arbitrarily set the initial virtual space to a multiple
3385 // of the boot class loader size.
3386 size_t word_size = VIRTUALSPACEMULTIPLIER * _first_chunk_word_size;
3387 word_size = align_up(word_size, Metaspace::reserve_alignment_words());
3388
3389 // Initialize the list of virtual spaces.
3390 _space_list = new VirtualSpaceList(word_size);
3391 _chunk_manager_metadata = new ChunkManager(SpecializedChunk, SmallChunk, MediumChunk);
3392
3393 if (!_space_list->initialization_succeeded()) {
3394 vm_exit_during_initialization("Unable to setup metadata virtual space list.", NULL);
3395 }
3396 }
3397
3398 _tracer = new MetaspaceTracer();
3399 }
3400
3401 void Metaspace::post_initialize() {
3402 MetaspaceGC::post_initialize();
3403 }
3404
3405 void Metaspace::initialize_first_chunk(MetaspaceType type, MetadataType mdtype) {
3406 Metachunk* chunk = get_initialization_chunk(type, mdtype);
3407 if (chunk != NULL) {
3408 // Add to this manager's list of chunks in use and current_chunk().
3409 get_space_manager(mdtype)->add_chunk(chunk, true);
3410 }
3411 }
3412
3413 Metachunk* Metaspace::get_initialization_chunk(MetaspaceType type, MetadataType mdtype) {
3414 size_t chunk_word_size = get_space_manager(mdtype)->get_initial_chunk_size(type);
3415
3416 // Get a chunk from the chunk freelist
3417 Metachunk* chunk = get_chunk_manager(mdtype)->chunk_freelist_allocate(chunk_word_size);
3418
3419 if (chunk == NULL) {
3420 chunk = get_space_list(mdtype)->get_new_chunk(chunk_word_size,
3421 get_space_manager(mdtype)->medium_chunk_bunch());
3422 }
3423
3424 // For dumping shared archive, report error if allocation has failed.
3425 if (DumpSharedSpaces && chunk == NULL) {
3426 report_insufficient_metaspace(MetaspaceAux::committed_bytes() + chunk_word_size * BytesPerWord);
3427 }
3428
3429 return chunk;
3430 }
3431
3432 void Metaspace::verify_global_initialization() {
3433 assert(space_list() != NULL, "Metadata VirtualSpaceList has not been initialized");
3434 assert(chunk_manager_metadata() != NULL, "Metadata ChunkManager has not been initialized");
3435
3436 if (using_class_space()) {
3437 assert(class_space_list() != NULL, "Class VirtualSpaceList has not been initialized");
3438 assert(chunk_manager_class() != NULL, "Class ChunkManager has not been initialized");
3439 }
3440 }
3441
3442 void Metaspace::initialize(Mutex* lock, MetaspaceType type) {
3443 verify_global_initialization();
3444
3445 // Allocate SpaceManager for metadata objects.
3446 _vsm = new SpaceManager(NonClassType, lock);
3447
3448 if (using_class_space()) {
3449 // Allocate SpaceManager for classes.
3450 _class_vsm = new SpaceManager(ClassType, lock);
3451 }
3452
3453 MutexLockerEx cl(SpaceManager::expand_lock(), Mutex::_no_safepoint_check_flag);
3454
3455 // Allocate chunk for metadata objects
3456 initialize_first_chunk(type, NonClassType);
3457
3458 // Allocate chunk for class metadata objects
3459 if (using_class_space()) {
3460 initialize_first_chunk(type, ClassType);
3461 }
3462
3463 _alloc_record_head = NULL;
3464 _alloc_record_tail = NULL;
3465 }
3466
3467 size_t Metaspace::align_word_size_up(size_t word_size) {
3468 size_t byte_size = word_size * wordSize;
3469 return ReservedSpace::allocation_align_size_up(byte_size) / wordSize;
3470 }
3471
3472 MetaWord* Metaspace::allocate(size_t word_size, MetadataType mdtype) {
3473 // DumpSharedSpaces doesn't use class metadata area (yet)
3474 // Also, don't use class_vsm() unless UseCompressedClassPointers is true.
3475 if (is_class_space_allocation(mdtype)) {
3476 return class_vsm()->allocate(word_size);
3477 } else {
3478 return vsm()->allocate(word_size);
3479 }
3480 }
3481
3482 MetaWord* Metaspace::expand_and_allocate(size_t word_size, MetadataType mdtype) {
3483 size_t delta_bytes = MetaspaceGC::delta_capacity_until_GC(word_size * BytesPerWord);
3484 assert(delta_bytes > 0, "Must be");
3485
3486 size_t before = 0;
3487 size_t after = 0;
3488 MetaWord* res;
3489 bool incremented;
3490
3491 // Each thread increments the HWM at most once. Even if the thread fails to increment
3492 // the HWM, an allocation is still attempted. This is because another thread must then
3493 // have incremented the HWM and therefore the allocation might still succeed.
3494 do {
3495 incremented = MetaspaceGC::inc_capacity_until_GC(delta_bytes, &after, &before);
3496 res = allocate(word_size, mdtype);
3497 } while (!incremented && res == NULL);
3498
3499 if (incremented) {
3500 tracer()->report_gc_threshold(before, after,
3501 MetaspaceGCThresholdUpdater::ExpandAndAllocate);
3502 log_trace(gc, metaspace)("Increase capacity to GC from " SIZE_FORMAT " to " SIZE_FORMAT, before, after);
3503 }
3504
3505 return res;
3506 }
3507
3508 // Space allocated in the Metaspace. This may
3509 // be across several metadata virtual spaces.
3510 char* Metaspace::bottom() const {
3511 assert(DumpSharedSpaces, "only useful and valid for dumping shared spaces");
3512 return (char*)vsm()->current_chunk()->bottom();
3513 }
3514
3515 size_t Metaspace::used_words_slow(MetadataType mdtype) const {
3516 if (mdtype == ClassType) {
3517 return using_class_space() ? class_vsm()->sum_used_in_chunks_in_use() : 0;
3518 } else {
3519 return vsm()->sum_used_in_chunks_in_use(); // includes overhead!
3520 }
3521 }
3522
3523 size_t Metaspace::free_words_slow(MetadataType mdtype) const {
3524 if (mdtype == ClassType) {
3525 return using_class_space() ? class_vsm()->sum_free_in_chunks_in_use() : 0;
3526 } else {
3527 return vsm()->sum_free_in_chunks_in_use();
3528 }
3529 }
3530
3531 // Space capacity in the Metaspace. It includes
3532 // space in the list of chunks from which allocations
3533 // have been made. Don't include space in the global freelist and
3534 // in the space available in the dictionary which
3535 // is already counted in some chunk.
3536 size_t Metaspace::capacity_words_slow(MetadataType mdtype) const {
3537 if (mdtype == ClassType) {
3538 return using_class_space() ? class_vsm()->sum_capacity_in_chunks_in_use() : 0;
3539 } else {
3540 return vsm()->sum_capacity_in_chunks_in_use();
3541 }
3542 }
3543
3544 size_t Metaspace::used_bytes_slow(MetadataType mdtype) const {
3545 return used_words_slow(mdtype) * BytesPerWord;
3546 }
3547
3548 size_t Metaspace::capacity_bytes_slow(MetadataType mdtype) const {
3549 return capacity_words_slow(mdtype) * BytesPerWord;
3550 }
3551
3552 size_t Metaspace::allocated_blocks_bytes() const {
3553 return vsm()->allocated_blocks_bytes() +
3554 (using_class_space() ? class_vsm()->allocated_blocks_bytes() : 0);
3555 }
3556
3557 size_t Metaspace::allocated_chunks_bytes() const {
3558 return vsm()->allocated_chunks_bytes() +
3559 (using_class_space() ? class_vsm()->allocated_chunks_bytes() : 0);
3560 }
3561
3562 void Metaspace::deallocate(MetaWord* ptr, size_t word_size, bool is_class) {
3563 assert(!SafepointSynchronize::is_at_safepoint()
3564 || Thread::current()->is_VM_thread(), "should be the VM thread");
3565
3566 if (DumpSharedSpaces && log_is_enabled(Info, cds)) {
3567 record_deallocation(ptr, vsm()->get_allocation_word_size(word_size));
3568 }
3569
3570 MutexLockerEx ml(vsm()->lock(), Mutex::_no_safepoint_check_flag);
3571
3572 if (is_class && using_class_space()) {
3573 class_vsm()->deallocate(ptr, word_size);
3574 } else {
3575 vsm()->deallocate(ptr, word_size);
3576 }
3577 }
3578
3579
3580 MetaWord* Metaspace::allocate(ClassLoaderData* loader_data, size_t word_size,
3581 bool read_only, MetaspaceObj::Type type, TRAPS) {
3582 if (HAS_PENDING_EXCEPTION) {
3583 assert(false, "Should not allocate with exception pending");
3584 return NULL; // caller does a CHECK_NULL too
3585 }
3586
3587 assert(loader_data != NULL, "Should never pass around a NULL loader_data. "
3588 "ClassLoaderData::the_null_class_loader_data() should have been used.");
3589
3590 // Allocate in metaspaces without taking out a lock, because it deadlocks
3591 // with the SymbolTable_lock. Dumping is single threaded for now. We'll have
3592 // to revisit this for application class data sharing.
3593 if (DumpSharedSpaces) {
3594 assert(type > MetaspaceObj::UnknownType && type < MetaspaceObj::_number_of_types, "sanity");
3595 Metaspace* space = read_only ? loader_data->ro_metaspace() : loader_data->rw_metaspace();
3596 MetaWord* result = space->allocate(word_size, NonClassType);
3597 if (result == NULL) {
3598 report_out_of_shared_space(read_only ? SharedReadOnly : SharedReadWrite);
3599 }
3600 if (log_is_enabled(Info, cds)) {
3601 space->record_allocation(result, type, space->vsm()->get_allocation_word_size(word_size));
3602 }
3603
3604 // Zero initialize.
3605 Copy::fill_to_words((HeapWord*)result, word_size, 0);
3606
3607 return result;
3608 }
3609
3610 MetadataType mdtype = (type == MetaspaceObj::ClassType) ? ClassType : NonClassType;
3611
3612 // Try to allocate metadata.
3613 MetaWord* result = loader_data->metaspace_non_null()->allocate(word_size, mdtype);
3614
3615 if (result == NULL) {
3616 tracer()->report_metaspace_allocation_failure(loader_data, word_size, type, mdtype);
3617
3618 // Allocation failed.
3619 if (is_init_completed()) {
3620 // Only start a GC if the bootstrapping has completed.
3621
3622 // Try to clean out some memory and retry.
3623 result = Universe::heap()->collector_policy()->satisfy_failed_metadata_allocation(
3624 loader_data, word_size, mdtype);
3625 }
3626 }
3627
3628 if (result == NULL) {
3629 SpaceManager* sm;
3630 if (is_class_space_allocation(mdtype)) {
3631 sm = loader_data->metaspace_non_null()->class_vsm();
3632 } else {
3633 sm = loader_data->metaspace_non_null()->vsm();
3634 }
3635
3636 result = sm->get_small_chunk_and_allocate(word_size);
3637
3638 if (result == NULL) {
3639 report_metadata_oome(loader_data, word_size, type, mdtype, CHECK_NULL);
3640 }
3641 }
3642
3643 // Zero initialize.
3644 Copy::fill_to_words((HeapWord*)result, word_size, 0);
3645
3646 return result;
3647 }
3648
3649 size_t Metaspace::class_chunk_size(size_t word_size) {
3650 assert(using_class_space(), "Has to use class space");
3651 return class_vsm()->calc_chunk_size(word_size);
3652 }
3653
3654 void Metaspace::report_metadata_oome(ClassLoaderData* loader_data, size_t word_size, MetaspaceObj::Type type, MetadataType mdtype, TRAPS) {
3655 tracer()->report_metadata_oom(loader_data, word_size, type, mdtype);
3656
3657 // If result is still null, we are out of memory.
3658 Log(gc, metaspace, freelist) log;
3659 if (log.is_info()) {
3660 log.info("Metaspace (%s) allocation failed for size " SIZE_FORMAT,
3661 is_class_space_allocation(mdtype) ? "class" : "data", word_size);
3662 ResourceMark rm;
3663 outputStream* out = log.info_stream();
3664 if (loader_data->metaspace_or_null() != NULL) {
3665 loader_data->dump(out);
3666 }
3667 MetaspaceAux::dump(out);
3668 }
3669
3670 bool out_of_compressed_class_space = false;
3671 if (is_class_space_allocation(mdtype)) {
3672 Metaspace* metaspace = loader_data->metaspace_non_null();
3673 out_of_compressed_class_space =
3674 MetaspaceAux::committed_bytes(Metaspace::ClassType) +
3675 (metaspace->class_chunk_size(word_size) * BytesPerWord) >
3676 CompressedClassSpaceSize;
3677 }
3678
3679 // -XX:+HeapDumpOnOutOfMemoryError and -XX:OnOutOfMemoryError support
3680 const char* space_string = out_of_compressed_class_space ?
3681 "Compressed class space" : "Metaspace";
3682
3683 report_java_out_of_memory(space_string);
3684
3685 if (JvmtiExport::should_post_resource_exhausted()) {
3686 JvmtiExport::post_resource_exhausted(
3687 JVMTI_RESOURCE_EXHAUSTED_OOM_ERROR,
3688 space_string);
3689 }
3690
3691 if (!is_init_completed()) {
3692 vm_exit_during_initialization("OutOfMemoryError", space_string);
3693 }
3694
3695 if (out_of_compressed_class_space) {
3696 THROW_OOP(Universe::out_of_memory_error_class_metaspace());
3697 } else {
3698 THROW_OOP(Universe::out_of_memory_error_metaspace());
3699 }
3700 }
3701
3702 const char* Metaspace::metadata_type_name(Metaspace::MetadataType mdtype) {
3703 switch (mdtype) {
3704 case Metaspace::ClassType: return "Class";
3705 case Metaspace::NonClassType: return "Metadata";
3706 default:
3707 assert(false, "Got bad mdtype: %d", (int) mdtype);
3708 return NULL;
3709 }
3710 }
3711
3712 void Metaspace::record_allocation(void* ptr, MetaspaceObj::Type type, size_t word_size) {
3713 assert(DumpSharedSpaces, "sanity");
3714
3715 int byte_size = (int)word_size * wordSize;
3716 AllocRecord *rec = new AllocRecord((address)ptr, type, byte_size);
3717
3718 if (_alloc_record_head == NULL) {
3719 _alloc_record_head = _alloc_record_tail = rec;
3720 } else if (_alloc_record_tail->_ptr + _alloc_record_tail->_byte_size == (address)ptr) {
3721 _alloc_record_tail->_next = rec;
3722 _alloc_record_tail = rec;
3723 } else {
3724 // slow linear search, but this doesn't happen that often, and only when dumping
3725 for (AllocRecord *old = _alloc_record_head; old; old = old->_next) {
3726 if (old->_ptr == ptr) {
3727 assert(old->_type == MetaspaceObj::DeallocatedType, "sanity");
3728 int remain_bytes = old->_byte_size - byte_size;
3729 assert(remain_bytes >= 0, "sanity");
3730 old->_type = type;
3731
3732 if (remain_bytes == 0) {
3733 delete(rec);
3734 } else {
3735 address remain_ptr = address(ptr) + byte_size;
3736 rec->_ptr = remain_ptr;
3737 rec->_byte_size = remain_bytes;
3738 rec->_type = MetaspaceObj::DeallocatedType;
3739 rec->_next = old->_next;
3740 old->_byte_size = byte_size;
3741 old->_next = rec;
3742 }
3743 return;
3744 }
3745 }
3746 assert(0, "reallocating a freed pointer that was not recorded");
3747 }
3748 }
3749
3750 void Metaspace::record_deallocation(void* ptr, size_t word_size) {
3751 assert(DumpSharedSpaces, "sanity");
3752
3753 for (AllocRecord *rec = _alloc_record_head; rec; rec = rec->_next) {
3754 if (rec->_ptr == ptr) {
3755 assert(rec->_byte_size == (int)word_size * wordSize, "sanity");
3756 rec->_type = MetaspaceObj::DeallocatedType;
3757 return;
3758 }
3759 }
3760
3761 assert(0, "deallocating a pointer that was not recorded");
3762 }
3763
3764 void Metaspace::iterate(Metaspace::AllocRecordClosure *closure) {
3765 assert(DumpSharedSpaces, "unimplemented for !DumpSharedSpaces");
3766
3767 address last_addr = (address)bottom();
3768
3769 for (AllocRecord *rec = _alloc_record_head; rec; rec = rec->_next) {
3770 address ptr = rec->_ptr;
3771 if (last_addr < ptr) {
3772 closure->doit(last_addr, MetaspaceObj::UnknownType, ptr - last_addr);
3773 }
3774 closure->doit(ptr, rec->_type, rec->_byte_size);
3775 last_addr = ptr + rec->_byte_size;
3776 }
3777
3778 address top = ((address)bottom()) + used_bytes_slow(Metaspace::NonClassType);
3779 if (last_addr < top) {
3780 closure->doit(last_addr, MetaspaceObj::UnknownType, top - last_addr);
3781 }
3782 }
3783
3784 void Metaspace::purge(MetadataType mdtype) {
3785 get_space_list(mdtype)->purge(get_chunk_manager(mdtype));
3786 }
3787
3788 void Metaspace::purge() {
3789 MutexLockerEx cl(SpaceManager::expand_lock(),
3790 Mutex::_no_safepoint_check_flag);
3791 purge(NonClassType);
3792 if (using_class_space()) {
3793 purge(ClassType);
3794 }
3795 }
3796
3797 void Metaspace::print_on(outputStream* out) const {
3798 // Print both class virtual space counts and metaspace.
3799 if (Verbose) {
3800 vsm()->print_on(out);
3801 if (using_class_space()) {
3802 class_vsm()->print_on(out);
3803 }
3804 }
3805 }
3806
3807 bool Metaspace::contains(const void* ptr) {
3808 if (UseSharedSpaces && MetaspaceShared::is_in_shared_space(ptr)) {
3809 return true;
3810 }
3811 return contains_non_shared(ptr);
3812 }
3813
3814 bool Metaspace::contains_non_shared(const void* ptr) {
3815 if (using_class_space() && get_space_list(ClassType)->contains(ptr)) {
3816 return true;
3817 }
3818
3819 return get_space_list(NonClassType)->contains(ptr);
3820 }
3821
3822 void Metaspace::verify() {
3823 vsm()->verify();
3824 if (using_class_space()) {
3825 class_vsm()->verify();
3826 }
3827 }
3828
3829 void Metaspace::dump(outputStream* const out) const {
3830 out->print_cr("\nVirtual space manager: " INTPTR_FORMAT, p2i(vsm()));
3831 vsm()->dump(out);
3832 if (using_class_space()) {
3833 out->print_cr("\nClass space manager: " INTPTR_FORMAT, p2i(class_vsm()));
3834 class_vsm()->dump(out);
3835 }
3836 }
3837
3838 /////////////// Unit tests ///////////////
3839
3840 #ifndef PRODUCT
3841
3842 class TestMetaspaceAuxTest : AllStatic {
3843 public:
3844 static void test_reserved() {
3845 size_t reserved = MetaspaceAux::reserved_bytes();
3846
3847 assert(reserved > 0, "assert");
3848
3849 size_t committed = MetaspaceAux::committed_bytes();
3850 assert(committed <= reserved, "assert");
3851
3852 size_t reserved_metadata = MetaspaceAux::reserved_bytes(Metaspace::NonClassType);
3853 assert(reserved_metadata > 0, "assert");
3854 assert(reserved_metadata <= reserved, "assert");
3855
3856 if (UseCompressedClassPointers) {
3857 size_t reserved_class = MetaspaceAux::reserved_bytes(Metaspace::ClassType);
3858 assert(reserved_class > 0, "assert");
3859 assert(reserved_class < reserved, "assert");
3860 }
3861 }
3862
3863 static void test_committed() {
3864 size_t committed = MetaspaceAux::committed_bytes();
3865
3866 assert(committed > 0, "assert");
3867
3868 size_t reserved = MetaspaceAux::reserved_bytes();
3869 assert(committed <= reserved, "assert");
3870
3871 size_t committed_metadata = MetaspaceAux::committed_bytes(Metaspace::NonClassType);
3872 assert(committed_metadata > 0, "assert");
3873 assert(committed_metadata <= committed, "assert");
3874
3875 if (UseCompressedClassPointers) {
3876 size_t committed_class = MetaspaceAux::committed_bytes(Metaspace::ClassType);
3877 assert(committed_class > 0, "assert");
3878 assert(committed_class < committed, "assert");
3879 }
3880 }
3881
3882 static void test_virtual_space_list_large_chunk() {
3883 VirtualSpaceList* vs_list = new VirtualSpaceList(os::vm_allocation_granularity());
3884 MutexLockerEx cl(SpaceManager::expand_lock(), Mutex::_no_safepoint_check_flag);
3885 // A size larger than VirtualSpaceSize (256k) and add one page to make it _not_ be
3886 // vm_allocation_granularity aligned on Windows.
3887 size_t large_size = (size_t)(2*256*K + (os::vm_page_size()/BytesPerWord));
3888 large_size += (os::vm_page_size()/BytesPerWord);
3889 vs_list->get_new_chunk(large_size, 0);
3890 }
3891
3892 static void test() {
3893 test_reserved();
3894 test_committed();
3895 test_virtual_space_list_large_chunk();
3896 }
3897 };
3898
3899 void TestMetaspaceAux_test() {
3900 TestMetaspaceAuxTest::test();
3901 }
3902
3903 class TestVirtualSpaceNodeTest {
3904 static void chunk_up(size_t words_left, size_t& num_medium_chunks,
3905 size_t& num_small_chunks,
3906 size_t& num_specialized_chunks) {
3907 num_medium_chunks = words_left / MediumChunk;
3908 words_left = words_left % MediumChunk;
3909
3910 num_small_chunks = words_left / SmallChunk;
3911 words_left = words_left % SmallChunk;
3912 // how many specialized chunks can we get?
3913 num_specialized_chunks = words_left / SpecializedChunk;
3914 assert(words_left % SpecializedChunk == 0, "should be nothing left");
3915 }
3916
3917 public:
3918 static void test() {
3919 MutexLockerEx ml(SpaceManager::expand_lock(), Mutex::_no_safepoint_check_flag);
3920 const size_t vsn_test_size_words = MediumChunk * 4;
3921 const size_t vsn_test_size_bytes = vsn_test_size_words * BytesPerWord;
3922
3923 // The chunk sizes must be multiples of eachother, or this will fail
3924 STATIC_ASSERT(MediumChunk % SmallChunk == 0);
3925 STATIC_ASSERT(SmallChunk % SpecializedChunk == 0);
3926
3927 { // No committed memory in VSN
3928 ChunkManager cm(SpecializedChunk, SmallChunk, MediumChunk);
3929 VirtualSpaceNode vsn(vsn_test_size_bytes);
3930 vsn.initialize();
3931 vsn.retire(&cm);
3932 assert(cm.sum_free_chunks_count() == 0, "did not commit any memory in the VSN");
3933 }
3934
3935 { // All of VSN is committed, half is used by chunks
3936 ChunkManager cm(SpecializedChunk, SmallChunk, MediumChunk);
3937 VirtualSpaceNode vsn(vsn_test_size_bytes);
3938 vsn.initialize();
3939 vsn.expand_by(vsn_test_size_words, vsn_test_size_words);
3940 vsn.get_chunk_vs(MediumChunk);
3941 vsn.get_chunk_vs(MediumChunk);
3942 vsn.retire(&cm);
3943 assert(cm.sum_free_chunks_count() == 2, "should have been memory left for 2 medium chunks");
3944 assert(cm.sum_free_chunks() == 2*MediumChunk, "sizes should add up");
3945 }
3946
3947 const size_t page_chunks = 4 * (size_t)os::vm_page_size() / BytesPerWord;
3948 // This doesn't work for systems with vm_page_size >= 16K.
3949 if (page_chunks < MediumChunk) {
3950 // 4 pages of VSN is committed, some is used by chunks
3951 ChunkManager cm(SpecializedChunk, SmallChunk, MediumChunk);
3952 VirtualSpaceNode vsn(vsn_test_size_bytes);
3953
3954 vsn.initialize();
3955 vsn.expand_by(page_chunks, page_chunks);
3956 vsn.get_chunk_vs(SmallChunk);
3957 vsn.get_chunk_vs(SpecializedChunk);
3958 vsn.retire(&cm);
3959
3960 // committed - used = words left to retire
3961 const size_t words_left = page_chunks - SmallChunk - SpecializedChunk;
3962
3963 size_t num_medium_chunks, num_small_chunks, num_spec_chunks;
3964 chunk_up(words_left, num_medium_chunks, num_small_chunks, num_spec_chunks);
3965
3966 assert(num_medium_chunks == 0, "should not get any medium chunks");
3967 assert(cm.sum_free_chunks_count() == (num_small_chunks + num_spec_chunks), "should be space for 3 chunks");
3968 assert(cm.sum_free_chunks() == words_left, "sizes should add up");
3969 }
3970
3971 { // Half of VSN is committed, a humongous chunk is used
3972 ChunkManager cm(SpecializedChunk, SmallChunk, MediumChunk);
3973 VirtualSpaceNode vsn(vsn_test_size_bytes);
3974 vsn.initialize();
3975 vsn.expand_by(MediumChunk * 2, MediumChunk * 2);
3976 vsn.get_chunk_vs(MediumChunk + SpecializedChunk); // Humongous chunks will be aligned up to MediumChunk + SpecializedChunk
3977 vsn.retire(&cm);
3978
3979 const size_t words_left = MediumChunk * 2 - (MediumChunk + SpecializedChunk);
3980 size_t num_medium_chunks, num_small_chunks, num_spec_chunks;
3981 chunk_up(words_left, num_medium_chunks, num_small_chunks, num_spec_chunks);
3982
3983 assert(num_medium_chunks == 0, "should not get any medium chunks");
3984 assert(cm.sum_free_chunks_count() == (num_small_chunks + num_spec_chunks), "should be space for 3 chunks");
3985 assert(cm.sum_free_chunks() == words_left, "sizes should add up");
3986 }
3987
3988 }
3989
3990 #define assert_is_available_positive(word_size) \
3991 assert(vsn.is_available(word_size), \
3992 #word_size ": " PTR_FORMAT " bytes were not available in " \
3993 "VirtualSpaceNode [" PTR_FORMAT ", " PTR_FORMAT ")", \
3994 (uintptr_t)(word_size * BytesPerWord), p2i(vsn.bottom()), p2i(vsn.end()));
3995
3996 #define assert_is_available_negative(word_size) \
3997 assert(!vsn.is_available(word_size), \
3998 #word_size ": " PTR_FORMAT " bytes should not be available in " \
3999 "VirtualSpaceNode [" PTR_FORMAT ", " PTR_FORMAT ")", \
4000 (uintptr_t)(word_size * BytesPerWord), p2i(vsn.bottom()), p2i(vsn.end()));
4001
4002 static void test_is_available_positive() {
4003 // Reserve some memory.
4004 VirtualSpaceNode vsn(os::vm_allocation_granularity());
4005 assert(vsn.initialize(), "Failed to setup VirtualSpaceNode");
4006
4007 // Commit some memory.
4008 size_t commit_word_size = os::vm_allocation_granularity() / BytesPerWord;
4009 bool expanded = vsn.expand_by(commit_word_size, commit_word_size);
4010 assert(expanded, "Failed to commit");
4011
4012 // Check that is_available accepts the committed size.
4013 assert_is_available_positive(commit_word_size);
4014
4015 // Check that is_available accepts half the committed size.
4016 size_t expand_word_size = commit_word_size / 2;
4017 assert_is_available_positive(expand_word_size);
4018 }
4019
4020 static void test_is_available_negative() {
4021 // Reserve some memory.
4022 VirtualSpaceNode vsn(os::vm_allocation_granularity());
4023 assert(vsn.initialize(), "Failed to setup VirtualSpaceNode");
4024
4025 // Commit some memory.
4026 size_t commit_word_size = os::vm_allocation_granularity() / BytesPerWord;
4027 bool expanded = vsn.expand_by(commit_word_size, commit_word_size);
4028 assert(expanded, "Failed to commit");
4029
4030 // Check that is_available doesn't accept a too large size.
4031 size_t two_times_commit_word_size = commit_word_size * 2;
4032 assert_is_available_negative(two_times_commit_word_size);
4033 }
4034
4035 static void test_is_available_overflow() {
4036 // Reserve some memory.
4037 VirtualSpaceNode vsn(os::vm_allocation_granularity());
4038 assert(vsn.initialize(), "Failed to setup VirtualSpaceNode");
4039
4040 // Commit some memory.
4041 size_t commit_word_size = os::vm_allocation_granularity() / BytesPerWord;
4042 bool expanded = vsn.expand_by(commit_word_size, commit_word_size);
4043 assert(expanded, "Failed to commit");
4044
4045 // Calculate a size that will overflow the virtual space size.
4046 void* virtual_space_max = (void*)(uintptr_t)-1;
4047 size_t bottom_to_max = pointer_delta(virtual_space_max, vsn.bottom(), 1);
4048 size_t overflow_size = bottom_to_max + BytesPerWord;
4049 size_t overflow_word_size = overflow_size / BytesPerWord;
4050
4051 // Check that is_available can handle the overflow.
4052 assert_is_available_negative(overflow_word_size);
4053 }
4054
4055 static void test_is_available() {
4056 TestVirtualSpaceNodeTest::test_is_available_positive();
4057 TestVirtualSpaceNodeTest::test_is_available_negative();
4058 TestVirtualSpaceNodeTest::test_is_available_overflow();
4059 }
4060 };
4061
4062 void TestVirtualSpaceNode_test() {
4063 TestVirtualSpaceNodeTest::test();
4064 TestVirtualSpaceNodeTest::test_is_available();
4065 }
4066
4067 // The following test is placed here instead of a gtest / unittest file
4068 // because the ChunkManager class is only available in this file.
4069 void ChunkManager_test_list_index() {
4070 ChunkManager manager(ClassSpecializedChunk, ClassSmallChunk, ClassMediumChunk);
4071
4072 // Test previous bug where a query for a humongous class metachunk,
4073 // incorrectly matched the non-class medium metachunk size.
4074 {
4075 assert(MediumChunk > ClassMediumChunk, "Precondition for test");
4076
4077 ChunkIndex index = manager.list_index(MediumChunk);
4078
4079 assert(index == HumongousIndex,
4080 "Requested size is larger than ClassMediumChunk,"
4081 " so should return HumongousIndex. Got index: %d", (int)index);
4082 }
4083
4084 // Check the specified sizes as well.
4085 {
4086 ChunkIndex index = manager.list_index(ClassSpecializedChunk);
4087 assert(index == SpecializedIndex, "Wrong index returned. Got index: %d", (int)index);
4088 }
4089 {
4090 ChunkIndex index = manager.list_index(ClassSmallChunk);
4091 assert(index == SmallIndex, "Wrong index returned. Got index: %d", (int)index);
4092 }
4093 {
4094 ChunkIndex index = manager.list_index(ClassMediumChunk);
4095 assert(index == MediumIndex, "Wrong index returned. Got index: %d", (int)index);
4096 }
4097 {
4098 ChunkIndex index = manager.list_index(ClassMediumChunk + 1);
4099 assert(index == HumongousIndex, "Wrong index returned. Got index: %d", (int)index);
4100 }
4101 }
4102
4103 #endif // !PRODUCT
4104
4105 #ifdef ASSERT
4106
4107 // ChunkManagerReturnTest stresses taking/returning chunks from the ChunkManager. It takes and
4108 // returns chunks from/to the ChunkManager while keeping track of the expected ChunkManager
4109 // content.
4110 class ChunkManagerReturnTestImpl {
4111
4112 VirtualSpaceNode _vsn;
4113 ChunkManager _cm;
4114
4115 // The expected content of the chunk manager.
4116 unsigned _chunks_in_chunkmanager;
4117 size_t _words_in_chunkmanager;
4118
4119 // A fixed size pool of chunks. Chunks may be in the chunk manager (free) or not (in use).
4120 static const int num_chunks = 256;
4121 Metachunk* _pool[num_chunks];
4122
4123 // Helper, return a random position into the chunk pool.
4124 static int get_random_position() {
4125 return os::random() % num_chunks;
4126 }
4127
4128 // Asserts that ChunkManager counters match expectations.
4129 void assert_counters() {
4130 assert(_vsn.container_count() == num_chunks - _chunks_in_chunkmanager, "vsn counter mismatch.");
4131 assert(_cm.free_chunks_count() == _chunks_in_chunkmanager, "cm counter mismatch.");
4132 assert(_cm.free_chunks_total_words() == _words_in_chunkmanager, "cm counter mismatch.");
4133 }
4134
4135 // Get a random chunk size. Equal chance to get spec/med/small chunk size or
4136 // a humongous chunk size. The latter itself is random in the range of [med+spec..4*med).
4137 size_t get_random_chunk_size() {
4138 const size_t sizes [] = { SpecializedChunk, SmallChunk, MediumChunk };
4139 const int rand = os::random() % 4;
4140 if (rand < 3) {
4141 return sizes[rand];
4142 } else {
4143 // Note: this affects the max. size of space (see _vsn initialization in ctor).
4144 return align_up(MediumChunk + 1 + (os::random() % (MediumChunk * 4)), SpecializedChunk);
4145 }
4146 }
4147
4148 // Starting at pool index <start>+1, find the next chunk tagged as either free or in use, depending
4149 // on <is_free>. Search wraps. Returns its position, or -1 if no matching chunk was found.
4150 int next_matching_chunk(int start, bool is_free) const {
4151 assert(start >= 0 && start < num_chunks, "invalid parameter");
4152 int pos = start;
4153 do {
4154 if (++pos == num_chunks) {
4155 pos = 0;
4156 }
4157 if (_pool[pos]->is_tagged_free() == is_free) {
4158 return pos;
4159 }
4160 } while (pos != start);
4161 return -1;
4162 }
4163
4164 // A structure to keep information about a chunk list including which
4165 // chunks are part of this list. This is needed to keep information about a chunk list
4166 // we will to return to the ChunkManager, because the original list will be destroyed.
4167 struct AChunkList {
4168 Metachunk* head;
4169 Metachunk* all[num_chunks];
4170 size_t size;
4171 int num;
4172 ChunkIndex index;
4173 };
4174
4175 // Assemble, from the in-use chunks (not in the chunk manager) in the pool,
4176 // a random chunk list of max. length <list_size> of chunks with the same
4177 // ChunkIndex (chunk size).
4178 // Returns false if list cannot be assembled. List is returned in the <out>
4179 // structure. Returned list may be smaller than <list_size>.
4180 bool assemble_random_chunklist(AChunkList* out, int list_size) {
4181 // Choose a random in-use chunk from the pool...
4182 const int headpos = next_matching_chunk(get_random_position(), false);
4183 if (headpos == -1) {
4184 return false;
4185 }
4186 Metachunk* const head = _pool[headpos];
4187 out->all[0] = head;
4188 assert(head->is_tagged_free() == false, "Chunk state mismatch");
4189 // ..then go from there, chain it up with up to list_size - 1 number of other
4190 // in-use chunks of the same index.
4191 const ChunkIndex index = _cm.list_index(head->word_size());
4192 int num_added = 1;
4193 size_t size_added = head->word_size();
4194 int pos = headpos;
4195 Metachunk* tail = head;
4196 do {
4197 pos = next_matching_chunk(pos, false);
4198 if (pos != headpos) {
4199 Metachunk* c = _pool[pos];
4200 assert(c->is_tagged_free() == false, "Chunk state mismatch");
4201 if (index == _cm.list_index(c->word_size())) {
4202 tail->set_next(c);
4203 c->set_prev(tail);
4204 tail = c;
4205 out->all[num_added] = c;
4206 num_added ++;
4207 size_added += c->word_size();
4208 }
4209 }
4210 } while (num_added < list_size && pos != headpos);
4211 out->head = head;
4212 out->index = index;
4213 out->size = size_added;
4214 out->num = num_added;
4215 return true;
4216 }
4217
4218 // Take a single random chunk from the ChunkManager.
4219 bool take_single_random_chunk_from_chunkmanager() {
4220 assert_counters();
4221 _cm.locked_verify();
4222 int pos = next_matching_chunk(get_random_position(), true);
4223 if (pos == -1) {
4224 return false;
4225 }
4226 Metachunk* c = _pool[pos];
4227 assert(c->is_tagged_free(), "Chunk state mismatch");
4228 // Note: instead of using ChunkManager::remove_chunk on this one chunk, we call
4229 // ChunkManager::free_chunks_get() with this chunk's word size. We really want
4230 // to exercise ChunkManager::free_chunks_get() because that one gets called for
4231 // normal chunk allocation.
4232 Metachunk* c2 = _cm.free_chunks_get(c->word_size());
4233 assert(c2 != NULL, "Unexpected.");
4234 assert(!c2->is_tagged_free(), "Chunk state mismatch");
4235 assert(c2->next() == NULL && c2->prev() == NULL, "Chunk should be outside of a list.");
4236 _chunks_in_chunkmanager --;
4237 _words_in_chunkmanager -= c->word_size();
4238 assert_counters();
4239 _cm.locked_verify();
4240 return true;
4241 }
4242
4243 // Returns a single random chunk to the chunk manager. Returns false if that
4244 // was not possible (all chunks are already in the chunk manager).
4245 bool return_single_random_chunk_to_chunkmanager() {
4246 assert_counters();
4247 _cm.locked_verify();
4248 int pos = next_matching_chunk(get_random_position(), false);
4249 if (pos == -1) {
4250 return false;
4251 }
4252 Metachunk* c = _pool[pos];
4253 assert(c->is_tagged_free() == false, "wrong chunk information");
4254 _cm.return_single_chunk(_cm.list_index(c->word_size()), c);
4255 _chunks_in_chunkmanager ++;
4256 _words_in_chunkmanager += c->word_size();
4257 assert(c->is_tagged_free() == true, "wrong chunk information");
4258 assert_counters();
4259 _cm.locked_verify();
4260 return true;
4261 }
4262
4263 // Return a random chunk list to the chunk manager. Returns the length of the
4264 // returned list.
4265 int return_random_chunk_list_to_chunkmanager(int list_size) {
4266 assert_counters();
4267 _cm.locked_verify();
4268 AChunkList aChunkList;
4269 if (!assemble_random_chunklist(&aChunkList, list_size)) {
4270 return 0;
4271 }
4272 // Before returning chunks are returned, they should be tagged in use.
4273 for (int i = 0; i < aChunkList.num; i ++) {
4274 assert(!aChunkList.all[i]->is_tagged_free(), "chunk state mismatch.");
4275 }
4276 _cm.return_chunk_list(aChunkList.index, aChunkList.head);
4277 _chunks_in_chunkmanager += aChunkList.num;
4278 _words_in_chunkmanager += aChunkList.size;
4279 // After all chunks are returned, check that they are now tagged free.
4280 for (int i = 0; i < aChunkList.num; i ++) {
4281 assert(aChunkList.all[i]->is_tagged_free(), "chunk state mismatch.");
4282 }
4283 assert_counters();
4284 _cm.locked_verify();
4285 return aChunkList.num;
4286 }
4287
4288 public:
4289
4290 ChunkManagerReturnTestImpl()
4291 : _vsn(align_up(MediumChunk * num_chunks * 5 * sizeof(MetaWord), Metaspace::reserve_alignment()))
4292 , _cm(SpecializedChunk, SmallChunk, MediumChunk)
4293 , _chunks_in_chunkmanager(0)
4294 , _words_in_chunkmanager(0)
4295 {
4296 MutexLockerEx ml(SpaceManager::expand_lock(), Mutex::_no_safepoint_check_flag);
4297 // Allocate virtual space and allocate random chunks. Keep these chunks in the _pool. These chunks are
4298 // "in use", because not yet added to any chunk manager.
4299 _vsn.initialize();
4300 _vsn.expand_by(_vsn.reserved_words(), _vsn.reserved_words());
4301 for (int i = 0; i < num_chunks; i ++) {
4302 const size_t size = get_random_chunk_size();
4303 _pool[i] = _vsn.get_chunk_vs(size);
4304 assert(_pool[i] != NULL, "allocation failed");
4305 }
4306 assert_counters();
4307 _cm.locked_verify();
4308 }
4309
4310 // Test entry point.
4311 // Return some chunks to the chunk manager (return phase). Take some chunks out (take phase). Repeat.
4312 // Chunks are choosen randomly. Number of chunks to return or taken are choosen randomly, but affected
4313 // by the <phase_length_factor> argument: a factor of 0.0 will cause the test to quickly alternate between
4314 // returning and taking, whereas a factor of 1.0 will take/return all chunks from/to the
4315 // chunks manager, thereby emptying or filling it completely.
4316 void do_test(float phase_length_factor) {
4317 MutexLockerEx ml(SpaceManager::expand_lock(), Mutex::_no_safepoint_check_flag);
4318 assert_counters();
4319 // Execute n operations, and operation being the move of a single chunk to/from the chunk manager.
4320 const int num_max_ops = num_chunks * 100;
4321 int num_ops = num_max_ops;
4322 const int average_phase_length = (int)(phase_length_factor * num_chunks);
4323 int num_ops_until_switch = MAX2(1, (average_phase_length + os::random() % 8 - 4));
4324 bool return_phase = true;
4325 while (num_ops > 0) {
4326 int chunks_moved = 0;
4327 if (return_phase) {
4328 // Randomly switch between returning a single chunk or a random length chunk list.
4329 if (os::random() % 2 == 0) {
4330 if (return_single_random_chunk_to_chunkmanager()) {
4331 chunks_moved = 1;
4332 }
4333 } else {
4334 const int list_length = MAX2(1, (os::random() % num_ops_until_switch));
4335 chunks_moved = return_random_chunk_list_to_chunkmanager(list_length);
4336 }
4337 } else {
4338 // Breath out.
4339 if (take_single_random_chunk_from_chunkmanager()) {
4340 chunks_moved = 1;
4341 }
4342 }
4343 num_ops -= chunks_moved;
4344 num_ops_until_switch -= chunks_moved;
4345 if (chunks_moved == 0 || num_ops_until_switch <= 0) {
4346 return_phase = !return_phase;
4347 num_ops_until_switch = MAX2(1, (average_phase_length + os::random() % 8 - 4));
4348 }
4349 }
4350 }
4351 };
4352
4353 void* setup_chunkmanager_returntests() {
4354 ChunkManagerReturnTestImpl* p = new ChunkManagerReturnTestImpl();
4355 return p;
4356 }
4357
4358 void teardown_chunkmanager_returntests(void* p) {
4359 delete (ChunkManagerReturnTestImpl*) p;
4360 }
4361
4362 void run_chunkmanager_returntests(void* p, float phase_length) {
4363 ChunkManagerReturnTestImpl* test = (ChunkManagerReturnTestImpl*) p;
4364 test->do_test(phase_length);
4365 }
4366
4367 // The following test is placed here instead of a gtest / unittest file
4368 // because the ChunkManager class is only available in this file.
4369 class SpaceManagerTest : AllStatic {
4370 friend void SpaceManager_test_adjust_initial_chunk_size();
4371
4372 static void test_adjust_initial_chunk_size(bool is_class) {
4373 const size_t smallest = SpaceManager::smallest_chunk_size(is_class);
4374 const size_t normal = SpaceManager::small_chunk_size(is_class);
4375 const size_t medium = SpaceManager::medium_chunk_size(is_class);
4376
4377 #define test_adjust_initial_chunk_size(value, expected, is_class_value) \
4378 do { \
4379 size_t v = value; \
4380 size_t e = expected; \
4381 assert(SpaceManager::adjust_initial_chunk_size(v, (is_class_value)) == e, \
4382 "Expected: " SIZE_FORMAT " got: " SIZE_FORMAT, e, v); \
4383 } while (0)
4384
4385 // Smallest (specialized)
4386 test_adjust_initial_chunk_size(1, smallest, is_class);
4387 test_adjust_initial_chunk_size(smallest - 1, smallest, is_class);
4388 test_adjust_initial_chunk_size(smallest, smallest, is_class);
4389
4390 // Small
4391 test_adjust_initial_chunk_size(smallest + 1, normal, is_class);
4392 test_adjust_initial_chunk_size(normal - 1, normal, is_class);
4393 test_adjust_initial_chunk_size(normal, normal, is_class);
4394
4395 // Medium
4396 test_adjust_initial_chunk_size(normal + 1, medium, is_class);
4397 test_adjust_initial_chunk_size(medium - 1, medium, is_class);
4398 test_adjust_initial_chunk_size(medium, medium, is_class);
4399
4400 // Humongous
4401 test_adjust_initial_chunk_size(medium + 1, medium + 1, is_class);
4402
4403 #undef test_adjust_initial_chunk_size
4404 }
4405
4406 static void test_adjust_initial_chunk_size() {
4407 test_adjust_initial_chunk_size(false);
4408 test_adjust_initial_chunk_size(true);
4409 }
4410 };
4411
4412 void SpaceManager_test_adjust_initial_chunk_size() {
4413 SpaceManagerTest::test_adjust_initial_chunk_size();
4414 }
4415
4416 #endif // ASSERT