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