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 "gc/shared/collectedHeap.hpp"
26 #include "gc/shared/collectorPolicy.hpp"
27 #include "gc/shared/gcLocker.hpp"
28 #include "logging/log.hpp"
29 #include "memory/allocation.hpp"
30 #include "memory/binaryTreeDictionary.hpp"
31 #include "memory/filemap.hpp"
32 #include "memory/freeList.hpp"
33 #include "memory/metachunk.hpp"
34 #include "memory/metaspace.hpp"
35 #include "memory/metaspaceGCThresholdUpdater.hpp"
36 #include "memory/metaspaceShared.hpp"
37 #include "memory/metaspaceTracer.hpp"
38 #include "memory/resourceArea.hpp"
39 #include "memory/universe.hpp"
40 #include "runtime/atomic.hpp"
41 #include "runtime/globals.hpp"
42 #include "runtime/init.hpp"
43 #include "runtime/java.hpp"
44 #include "runtime/mutex.hpp"
45 #include "runtime/orderAccess.inline.hpp"
46 #include "services/memTracker.hpp"
47 #include "services/memoryService.hpp"
48 #include "utilities/copy.hpp"
49 #include "utilities/debug.hpp"
50 #include "utilities/macros.hpp"
51
52 typedef BinaryTreeDictionary<Metablock, FreeList<Metablock> > BlockTreeDictionary;
53 typedef BinaryTreeDictionary<Metachunk, FreeList<Metachunk> > ChunkTreeDictionary;
54
55 // Set this constant to enable slow integrity checking of the free chunk lists
56 const bool metaspace_slow_verify = false;
57
58 size_t const allocation_from_dictionary_limit = 4 * K;
59
60 MetaWord* last_allocated = 0;
61
62 size_t Metaspace::_compressed_class_space_size;
63 const MetaspaceTracer* Metaspace::_tracer = NULL;
64
65 // Used in declarations in SpaceManager and ChunkManager
66 enum ChunkIndex {
67 ZeroIndex = 0,
68 SpecializedIndex = ZeroIndex,
69 SmallIndex = SpecializedIndex + 1,
70 MediumIndex = SmallIndex + 1,
71 HumongousIndex = MediumIndex + 1,
72 NumberOfFreeLists = 3,
73 NumberOfInUseLists = 4
74 };
75
76 enum ChunkSizes { // in words.
77 ClassSpecializedChunk = 128,
78 SpecializedChunk = 128,
79 ClassSmallChunk = 256,
80 SmallChunk = 512,
81 ClassMediumChunk = 4 * K,
82 MediumChunk = 8 * K
83 };
84
85 static ChunkIndex next_chunk_index(ChunkIndex i) {
86 assert(i < NumberOfInUseLists, "Out of bound");
87 return (ChunkIndex) (i+1);
88 }
89
90 volatile intptr_t MetaspaceGC::_capacity_until_GC = 0;
91 uint MetaspaceGC::_shrink_factor = 0;
92 bool MetaspaceGC::_should_concurrent_collect = false;
93
94 typedef class FreeList<Metachunk> ChunkList;
95
96 // Manages the global free lists of chunks.
97 class ChunkManager : public CHeapObj<mtInternal> {
98 friend class TestVirtualSpaceNodeTest;
99
100 // Free list of chunks of different sizes.
101 // SpecializedChunk
102 // SmallChunk
103 // MediumChunk
104 // HumongousChunk
105 ChunkList _free_chunks[NumberOfFreeLists];
106
107 // HumongousChunk
108 ChunkTreeDictionary _humongous_dictionary;
109
110 // ChunkManager in all lists of this type
111 size_t _free_chunks_total;
112 size_t _free_chunks_count;
113
114 void dec_free_chunks_total(size_t v) {
115 assert(_free_chunks_count > 0 &&
116 _free_chunks_total > 0,
117 "About to go negative");
118 Atomic::add_ptr(-1, &_free_chunks_count);
119 jlong minus_v = (jlong) - (jlong) v;
120 Atomic::add_ptr(minus_v, &_free_chunks_total);
121 }
122
123 // Debug support
124
125 size_t sum_free_chunks();
126 size_t sum_free_chunks_count();
127
128 void locked_verify_free_chunks_total();
129 void slow_locked_verify_free_chunks_total() {
130 if (metaspace_slow_verify) {
131 locked_verify_free_chunks_total();
132 }
133 }
134 void locked_verify_free_chunks_count();
135 void slow_locked_verify_free_chunks_count() {
136 if (metaspace_slow_verify) {
137 locked_verify_free_chunks_count();
138 }
139 }
140 void verify_free_chunks_count();
141
142 public:
143
144 ChunkManager(size_t specialized_size, size_t small_size, size_t medium_size)
145 : _free_chunks_total(0), _free_chunks_count(0) {
146 _free_chunks[SpecializedIndex].set_size(specialized_size);
147 _free_chunks[SmallIndex].set_size(small_size);
148 _free_chunks[MediumIndex].set_size(medium_size);
149 }
150
151 // add or delete (return) a chunk to the global freelist.
152 Metachunk* chunk_freelist_allocate(size_t word_size);
153
154 // Map a size to a list index assuming that there are lists
155 // for special, small, medium, and humongous chunks.
156 static ChunkIndex list_index(size_t size);
157
158 // Remove the chunk from its freelist. It is
159 // expected to be on one of the _free_chunks[] lists.
160 void remove_chunk(Metachunk* chunk);
161
162 // Add the simple linked list of chunks to the freelist of chunks
163 // of type index.
164 void return_chunks(ChunkIndex index, Metachunk* chunks);
165
166 // Total of the space in the free chunks list
167 size_t free_chunks_total_words();
168 size_t free_chunks_total_bytes();
169
170 // Number of chunks in the free chunks list
171 size_t free_chunks_count();
172
173 void inc_free_chunks_total(size_t v, size_t count = 1) {
174 Atomic::add_ptr(count, &_free_chunks_count);
175 Atomic::add_ptr(v, &_free_chunks_total);
176 }
177 ChunkTreeDictionary* humongous_dictionary() {
178 return &_humongous_dictionary;
179 }
180
181 ChunkList* free_chunks(ChunkIndex index);
182
183 // Returns the list for the given chunk word size.
184 ChunkList* find_free_chunks_list(size_t word_size);
185
186 // Remove from a list by size. Selects list based on size of chunk.
187 Metachunk* free_chunks_get(size_t chunk_word_size);
188
189 #define index_bounds_check(index) \
190 assert(index == SpecializedIndex || \
191 index == SmallIndex || \
192 index == MediumIndex || \
193 index == HumongousIndex, "Bad index: %d", (int) index)
194
195 size_t num_free_chunks(ChunkIndex index) const {
196 index_bounds_check(index);
197
198 if (index == HumongousIndex) {
199 return _humongous_dictionary.total_free_blocks();
200 }
201
202 ssize_t count = _free_chunks[index].count();
203 return count == -1 ? 0 : (size_t) count;
204 }
205
206 size_t size_free_chunks_in_bytes(ChunkIndex index) const {
207 index_bounds_check(index);
208
209 size_t word_size = 0;
210 if (index == HumongousIndex) {
211 word_size = _humongous_dictionary.total_size();
212 } else {
213 const size_t size_per_chunk_in_words = _free_chunks[index].size();
214 word_size = size_per_chunk_in_words * num_free_chunks(index);
215 }
216
217 return word_size * BytesPerWord;
218 }
219
220 MetaspaceChunkFreeListSummary chunk_free_list_summary() const {
221 return MetaspaceChunkFreeListSummary(num_free_chunks(SpecializedIndex),
222 num_free_chunks(SmallIndex),
223 num_free_chunks(MediumIndex),
224 num_free_chunks(HumongousIndex),
225 size_free_chunks_in_bytes(SpecializedIndex),
226 size_free_chunks_in_bytes(SmallIndex),
227 size_free_chunks_in_bytes(MediumIndex),
228 size_free_chunks_in_bytes(HumongousIndex));
229 }
230
231 // Debug support
232 void verify();
233 void slow_verify() {
234 if (metaspace_slow_verify) {
235 verify();
236 }
237 }
238 void locked_verify();
239 void slow_locked_verify() {
240 if (metaspace_slow_verify) {
241 locked_verify();
242 }
243 }
244 void verify_free_chunks_total();
245
246 void locked_print_free_chunks(outputStream* st);
247 void locked_print_sum_free_chunks(outputStream* st);
248
249 void print_on(outputStream* st) const;
250 };
251
252 // Used to manage the free list of Metablocks (a block corresponds
253 // to the allocation of a quantum of metadata).
254 class BlockFreelist VALUE_OBJ_CLASS_SPEC {
255 BlockTreeDictionary* const _dictionary;
256
257 // Only allocate and split from freelist if the size of the allocation
258 // is at least 1/4th the size of the available block.
259 const static int WasteMultiplier = 4;
260
261 // Accessors
262 BlockTreeDictionary* dictionary() const { return _dictionary; }
263
264 public:
265 BlockFreelist();
266 ~BlockFreelist();
267
268 // Get and return a block to the free list
269 MetaWord* get_block(size_t word_size);
270 void return_block(MetaWord* p, size_t word_size);
271
272 size_t total_size() { return dictionary()->total_size(); }
273
274 void print_on(outputStream* st) const;
275 };
276
277 // A VirtualSpaceList node.
278 class VirtualSpaceNode : public CHeapObj<mtClass> {
279 friend class VirtualSpaceList;
280
281 // Link to next VirtualSpaceNode
282 VirtualSpaceNode* _next;
283
284 // total in the VirtualSpace
285 MemRegion _reserved;
286 ReservedSpace _rs;
287 VirtualSpace _virtual_space;
288 MetaWord* _top;
289 // count of chunks contained in this VirtualSpace
290 uintx _container_count;
291
292 // Convenience functions to access the _virtual_space
293 char* low() const { return virtual_space()->low(); }
294 char* high() const { return virtual_space()->high(); }
295
296 // The first Metachunk will be allocated at the bottom of the
297 // VirtualSpace
298 Metachunk* first_chunk() { return (Metachunk*) bottom(); }
299
300 // Committed but unused space in the virtual space
301 size_t free_words_in_vs() const;
302 public:
303
304 VirtualSpaceNode(size_t byte_size);
305 VirtualSpaceNode(ReservedSpace rs) : _top(NULL), _next(NULL), _rs(rs), _container_count(0) {}
306 ~VirtualSpaceNode();
307
308 // Convenience functions for logical bottom and end
309 MetaWord* bottom() const { return (MetaWord*) _virtual_space.low(); }
310 MetaWord* end() const { return (MetaWord*) _virtual_space.high(); }
311
312 bool contains(const void* ptr) { return ptr >= low() && ptr < high(); }
313
314 size_t reserved_words() const { return _virtual_space.reserved_size() / BytesPerWord; }
315 size_t committed_words() const { return _virtual_space.actual_committed_size() / BytesPerWord; }
316
317 bool is_pre_committed() const { return _virtual_space.special(); }
318
319 // address of next available space in _virtual_space;
320 // Accessors
321 VirtualSpaceNode* next() { return _next; }
322 void set_next(VirtualSpaceNode* v) { _next = v; }
323
324 void set_reserved(MemRegion const v) { _reserved = v; }
325 void set_top(MetaWord* v) { _top = v; }
326
327 // Accessors
328 MemRegion* reserved() { return &_reserved; }
329 VirtualSpace* virtual_space() const { return (VirtualSpace*) &_virtual_space; }
330
331 // Returns true if "word_size" is available in the VirtualSpace
332 bool is_available(size_t word_size) { return word_size <= pointer_delta(end(), _top, sizeof(MetaWord)); }
333
334 MetaWord* top() const { return _top; }
335 void inc_top(size_t word_size) { _top += word_size; }
336
337 uintx container_count() { return _container_count; }
338 void inc_container_count();
339 void dec_container_count();
340 #ifdef ASSERT
341 uintx container_count_slow();
342 void verify_container_count();
343 #endif
344
345 // used and capacity in this single entry in the list
346 size_t used_words_in_vs() const;
347 size_t capacity_words_in_vs() const;
348
349 bool initialize();
350
351 // get space from the virtual space
352 Metachunk* take_from_committed(size_t chunk_word_size);
353
354 // Allocate a chunk from the virtual space and return it.
355 Metachunk* get_chunk_vs(size_t chunk_word_size);
356
357 // Expands/shrinks the committed space in a virtual space. Delegates
358 // to Virtualspace
359 bool expand_by(size_t min_words, size_t preferred_words);
360
361 // In preparation for deleting this node, remove all the chunks
362 // in the node from any freelist.
363 void purge(ChunkManager* chunk_manager);
364
365 // If an allocation doesn't fit in the current node a new node is created.
366 // Allocate chunks out of the remaining committed space in this node
367 // to avoid wasting that memory.
368 // This always adds up because all the chunk sizes are multiples of
369 // the smallest chunk size.
370 void retire(ChunkManager* chunk_manager);
371
372 #ifdef ASSERT
373 // Debug support
374 void mangle();
375 #endif
376
377 void print_on(outputStream* st) const;
378 };
379
380 #define assert_is_ptr_aligned(ptr, alignment) \
381 assert(is_ptr_aligned(ptr, alignment), \
382 PTR_FORMAT " is not aligned to " \
383 SIZE_FORMAT, p2i(ptr), alignment)
384
385 #define assert_is_size_aligned(size, alignment) \
386 assert(is_size_aligned(size, alignment), \
387 SIZE_FORMAT " is not aligned to " \
388 SIZE_FORMAT, size, alignment)
389
390
391 // Decide if large pages should be committed when the memory is reserved.
392 static bool should_commit_large_pages_when_reserving(size_t bytes) {
393 if (UseLargePages && UseLargePagesInMetaspace && !os::can_commit_large_page_memory()) {
394 size_t words = bytes / BytesPerWord;
395 bool is_class = false; // We never reserve large pages for the class space.
396 if (MetaspaceGC::can_expand(words, is_class) &&
397 MetaspaceGC::allowed_expansion() >= words) {
398 return true;
399 }
400 }
401
402 return false;
403 }
404
405 // byte_size is the size of the associated virtualspace.
406 VirtualSpaceNode::VirtualSpaceNode(size_t bytes) : _top(NULL), _next(NULL), _rs(), _container_count(0) {
407 assert_is_size_aligned(bytes, Metaspace::reserve_alignment());
408
409 #if INCLUDE_CDS
410 // This allocates memory with mmap. For DumpSharedspaces, try to reserve
411 // configurable address, generally at the top of the Java heap so other
412 // memory addresses don't conflict.
413 if (DumpSharedSpaces) {
414 bool large_pages = false; // No large pages when dumping the CDS archive.
415 char* shared_base = (char*)align_ptr_up((char*)SharedBaseAddress, Metaspace::reserve_alignment());
416
417 _rs = ReservedSpace(bytes, Metaspace::reserve_alignment(), large_pages, shared_base);
418 if (_rs.is_reserved()) {
419 assert(shared_base == 0 || _rs.base() == shared_base, "should match");
420 } else {
421 // Get a mmap region anywhere if the SharedBaseAddress fails.
422 _rs = ReservedSpace(bytes, Metaspace::reserve_alignment(), large_pages);
423 }
424 MetaspaceShared::initialize_shared_rs(&_rs);
425 } else
426 #endif
427 {
428 bool large_pages = should_commit_large_pages_when_reserving(bytes);
429
430 _rs = ReservedSpace(bytes, Metaspace::reserve_alignment(), large_pages);
431 }
432
433 if (_rs.is_reserved()) {
434 assert(_rs.base() != NULL, "Catch if we get a NULL address");
435 assert(_rs.size() != 0, "Catch if we get a 0 size");
436 assert_is_ptr_aligned(_rs.base(), Metaspace::reserve_alignment());
437 assert_is_size_aligned(_rs.size(), Metaspace::reserve_alignment());
438
439 MemTracker::record_virtual_memory_type((address)_rs.base(), mtClass);
440 }
441 }
442
443 void VirtualSpaceNode::purge(ChunkManager* chunk_manager) {
444 Metachunk* chunk = first_chunk();
445 Metachunk* invalid_chunk = (Metachunk*) top();
446 while (chunk < invalid_chunk ) {
447 assert(chunk->is_tagged_free(), "Should be tagged free");
448 MetaWord* next = ((MetaWord*)chunk) + chunk->word_size();
449 chunk_manager->remove_chunk(chunk);
450 assert(chunk->next() == NULL &&
451 chunk->prev() == NULL,
452 "Was not removed from its list");
453 chunk = (Metachunk*) next;
454 }
455 }
456
457 #ifdef ASSERT
458 uintx VirtualSpaceNode::container_count_slow() {
459 uintx count = 0;
460 Metachunk* chunk = first_chunk();
461 Metachunk* invalid_chunk = (Metachunk*) top();
462 while (chunk < invalid_chunk ) {
463 MetaWord* next = ((MetaWord*)chunk) + chunk->word_size();
464 // Don't count the chunks on the free lists. Those are
465 // still part of the VirtualSpaceNode but not currently
466 // counted.
467 if (!chunk->is_tagged_free()) {
468 count++;
469 }
470 chunk = (Metachunk*) next;
471 }
472 return count;
473 }
474 #endif
475
476 // List of VirtualSpaces for metadata allocation.
477 class VirtualSpaceList : public CHeapObj<mtClass> {
478 friend class VirtualSpaceNode;
479
480 enum VirtualSpaceSizes {
481 VirtualSpaceSize = 256 * K
482 };
483
484 // Head of the list
485 VirtualSpaceNode* _virtual_space_list;
486 // virtual space currently being used for allocations
487 VirtualSpaceNode* _current_virtual_space;
488
489 // Is this VirtualSpaceList used for the compressed class space
490 bool _is_class;
491
492 // Sum of reserved and committed memory in the virtual spaces
493 size_t _reserved_words;
494 size_t _committed_words;
495
496 // Number of virtual spaces
497 size_t _virtual_space_count;
498
499 ~VirtualSpaceList();
500
501 VirtualSpaceNode* virtual_space_list() const { return _virtual_space_list; }
502
503 void set_virtual_space_list(VirtualSpaceNode* v) {
504 _virtual_space_list = v;
505 }
506 void set_current_virtual_space(VirtualSpaceNode* v) {
507 _current_virtual_space = v;
508 }
509
510 void link_vs(VirtualSpaceNode* new_entry);
511
512 // Get another virtual space and add it to the list. This
513 // is typically prompted by a failed attempt to allocate a chunk
514 // and is typically followed by the allocation of a chunk.
515 bool create_new_virtual_space(size_t vs_word_size);
516
517 // Chunk up the unused committed space in the current
518 // virtual space and add the chunks to the free list.
519 void retire_current_virtual_space();
520
521 public:
522 VirtualSpaceList(size_t word_size);
523 VirtualSpaceList(ReservedSpace rs);
524
525 size_t free_bytes();
526
527 Metachunk* get_new_chunk(size_t word_size,
528 size_t grow_chunks_by_words,
529 size_t medium_chunk_bunch);
530
531 bool expand_node_by(VirtualSpaceNode* node,
532 size_t min_words,
533 size_t preferred_words);
534
535 bool expand_by(size_t min_words,
536 size_t preferred_words);
537
538 VirtualSpaceNode* current_virtual_space() {
539 return _current_virtual_space;
540 }
541
542 bool is_class() const { return _is_class; }
543
544 bool initialization_succeeded() { return _virtual_space_list != NULL; }
545
546 size_t reserved_words() { return _reserved_words; }
547 size_t reserved_bytes() { return reserved_words() * BytesPerWord; }
548 size_t committed_words() { return _committed_words; }
549 size_t committed_bytes() { return committed_words() * BytesPerWord; }
550
551 void inc_reserved_words(size_t v);
552 void dec_reserved_words(size_t v);
553 void inc_committed_words(size_t v);
554 void dec_committed_words(size_t v);
555 void inc_virtual_space_count();
556 void dec_virtual_space_count();
557
558 bool contains(const void* ptr);
559
560 // Unlink empty VirtualSpaceNodes and free it.
561 void purge(ChunkManager* chunk_manager);
562
563 void print_on(outputStream* st) const;
564
565 class VirtualSpaceListIterator : public StackObj {
566 VirtualSpaceNode* _virtual_spaces;
567 public:
568 VirtualSpaceListIterator(VirtualSpaceNode* virtual_spaces) :
569 _virtual_spaces(virtual_spaces) {}
570
571 bool repeat() {
572 return _virtual_spaces != NULL;
573 }
574
575 VirtualSpaceNode* get_next() {
576 VirtualSpaceNode* result = _virtual_spaces;
577 if (_virtual_spaces != NULL) {
578 _virtual_spaces = _virtual_spaces->next();
579 }
580 return result;
581 }
582 };
583 };
584
585 class Metadebug : AllStatic {
586 // Debugging support for Metaspaces
587 static int _allocation_fail_alot_count;
588
589 public:
590
591 static void init_allocation_fail_alot_count();
592 #ifdef ASSERT
593 static bool test_metadata_failure();
594 #endif
595 };
596
597 int Metadebug::_allocation_fail_alot_count = 0;
598
599 // SpaceManager - used by Metaspace to handle allocations
600 class SpaceManager : public CHeapObj<mtClass> {
601 friend class Metaspace;
602 friend class Metadebug;
603
604 private:
605
606 // protects allocations
607 Mutex* const _lock;
608
609 // Type of metadata allocated.
610 Metaspace::MetadataType _mdtype;
611
612 // List of chunks in use by this SpaceManager. Allocations
613 // are done from the current chunk. The list is used for deallocating
614 // chunks when the SpaceManager is freed.
615 Metachunk* _chunks_in_use[NumberOfInUseLists];
616 Metachunk* _current_chunk;
617
618 // Maximum number of small chunks to allocate to a SpaceManager
619 static uint const _small_chunk_limit;
620
621 // Sum of all space in allocated chunks
622 size_t _allocated_blocks_words;
623
624 // Sum of all allocated chunks
625 size_t _allocated_chunks_words;
626 size_t _allocated_chunks_count;
627
628 // Free lists of blocks are per SpaceManager since they
629 // are assumed to be in chunks in use by the SpaceManager
630 // and all chunks in use by a SpaceManager are freed when
631 // the class loader using the SpaceManager is collected.
632 BlockFreelist _block_freelists;
633
634 // protects virtualspace and chunk expansions
635 static const char* _expand_lock_name;
636 static const int _expand_lock_rank;
637 static Mutex* const _expand_lock;
638
639 private:
640 // Accessors
641 Metachunk* chunks_in_use(ChunkIndex index) const { return _chunks_in_use[index]; }
642 void set_chunks_in_use(ChunkIndex index, Metachunk* v) {
643 _chunks_in_use[index] = v;
644 }
645
646 BlockFreelist* block_freelists() const {
647 return (BlockFreelist*) &_block_freelists;
648 }
649
650 Metaspace::MetadataType mdtype() { return _mdtype; }
651
652 VirtualSpaceList* vs_list() const { return Metaspace::get_space_list(_mdtype); }
653 ChunkManager* chunk_manager() const { return Metaspace::get_chunk_manager(_mdtype); }
654
655 Metachunk* current_chunk() const { return _current_chunk; }
656 void set_current_chunk(Metachunk* v) {
657 _current_chunk = v;
658 }
659
660 Metachunk* find_current_chunk(size_t word_size);
661
662 // Add chunk to the list of chunks in use
663 void add_chunk(Metachunk* v, bool make_current);
664 void retire_current_chunk();
665
666 Mutex* lock() const { return _lock; }
667
668 const char* chunk_size_name(ChunkIndex index) const;
669
670 protected:
671 void initialize();
672
673 public:
674 SpaceManager(Metaspace::MetadataType mdtype,
675 Mutex* lock);
676 ~SpaceManager();
677
678 enum ChunkMultiples {
679 MediumChunkMultiple = 4
680 };
681
682 bool is_class() { return _mdtype == Metaspace::ClassType; }
683
684 // Accessors
685 size_t specialized_chunk_size() { return (size_t) is_class() ? ClassSpecializedChunk : SpecializedChunk; }
686 size_t small_chunk_size() { return (size_t) is_class() ? ClassSmallChunk : SmallChunk; }
687 size_t medium_chunk_size() { return (size_t) is_class() ? ClassMediumChunk : MediumChunk; }
688 size_t medium_chunk_bunch() { return medium_chunk_size() * MediumChunkMultiple; }
689
690 size_t smallest_chunk_size() { return specialized_chunk_size(); }
691
692 size_t allocated_blocks_words() const { return _allocated_blocks_words; }
693 size_t allocated_blocks_bytes() const { return _allocated_blocks_words * BytesPerWord; }
694 size_t allocated_chunks_words() const { return _allocated_chunks_words; }
695 size_t allocated_chunks_bytes() const { return _allocated_chunks_words * BytesPerWord; }
696 size_t allocated_chunks_count() const { return _allocated_chunks_count; }
697
698 bool is_humongous(size_t word_size) { return word_size > medium_chunk_size(); }
699
700 static Mutex* expand_lock() { return _expand_lock; }
701
702 // Increment the per Metaspace and global running sums for Metachunks
703 // by the given size. This is used when a Metachunk to added to
704 // the in-use list.
705 void inc_size_metrics(size_t words);
706 // Increment the per Metaspace and global running sums Metablocks by the given
707 // size. This is used when a Metablock is allocated.
708 void inc_used_metrics(size_t words);
709 // Delete the portion of the running sums for this SpaceManager. That is,
710 // the globals running sums for the Metachunks and Metablocks are
711 // decremented for all the Metachunks in-use by this SpaceManager.
712 void dec_total_from_size_metrics();
713
714 // Set the sizes for the initial chunks.
715 void get_initial_chunk_sizes(Metaspace::MetaspaceType type,
716 size_t* chunk_word_size,
717 size_t* class_chunk_word_size);
718
719 size_t sum_capacity_in_chunks_in_use() const;
720 size_t sum_used_in_chunks_in_use() const;
721 size_t sum_free_in_chunks_in_use() const;
722 size_t sum_waste_in_chunks_in_use() const;
723 size_t sum_waste_in_chunks_in_use(ChunkIndex index ) const;
724
725 size_t sum_count_in_chunks_in_use();
726 size_t sum_count_in_chunks_in_use(ChunkIndex i);
727
728 Metachunk* get_new_chunk(size_t word_size, size_t grow_chunks_by_words);
729
730 // Block allocation and deallocation.
731 // Allocates a block from the current chunk
732 MetaWord* allocate(size_t word_size);
733 // Allocates a block from a small chunk
734 MetaWord* get_small_chunk_and_allocate(size_t word_size);
735
736 // Helper for allocations
737 MetaWord* allocate_work(size_t word_size);
738
739 // Returns a block to the per manager freelist
740 void deallocate(MetaWord* p, size_t word_size);
741
742 // Based on the allocation size and a minimum chunk size,
743 // returned chunk size (for expanding space for chunk allocation).
744 size_t calc_chunk_size(size_t allocation_word_size);
745
746 // Called when an allocation from the current chunk fails.
747 // Gets a new chunk (may require getting a new virtual space),
748 // and allocates from that chunk.
749 MetaWord* grow_and_allocate(size_t word_size);
750
751 // Notify memory usage to MemoryService.
752 void track_metaspace_memory_usage();
753
754 // debugging support.
755
756 void dump(outputStream* const out) const;
757 void print_on(outputStream* st) const;
758 void locked_print_chunks_in_use_on(outputStream* st) const;
759
760 void verify();
761 void verify_chunk_size(Metachunk* chunk);
762 #ifdef ASSERT
763 void verify_allocated_blocks_words();
764 #endif
765
766 size_t get_raw_word_size(size_t word_size) {
767 size_t byte_size = word_size * BytesPerWord;
768
769 size_t raw_bytes_size = MAX2(byte_size, sizeof(Metablock));
770 raw_bytes_size = align_size_up(raw_bytes_size, Metachunk::object_alignment());
771
772 size_t raw_word_size = raw_bytes_size / BytesPerWord;
773 assert(raw_word_size * BytesPerWord == raw_bytes_size, "Size problem");
774
775 return raw_word_size;
776 }
777 };
778
779 uint const SpaceManager::_small_chunk_limit = 4;
780
781 const char* SpaceManager::_expand_lock_name =
782 "SpaceManager chunk allocation lock";
783 const int SpaceManager::_expand_lock_rank = Monitor::leaf - 1;
784 Mutex* const SpaceManager::_expand_lock =
785 new Mutex(SpaceManager::_expand_lock_rank,
786 SpaceManager::_expand_lock_name,
787 Mutex::_allow_vm_block_flag,
788 Monitor::_safepoint_check_never);
789
790 void VirtualSpaceNode::inc_container_count() {
791 assert_lock_strong(SpaceManager::expand_lock());
792 _container_count++;
793 }
794
795 void VirtualSpaceNode::dec_container_count() {
796 assert_lock_strong(SpaceManager::expand_lock());
797 _container_count--;
798 }
799
800 #ifdef ASSERT
801 void VirtualSpaceNode::verify_container_count() {
802 assert(_container_count == container_count_slow(),
803 "Inconsistency in container_count _container_count " UINTX_FORMAT
804 " container_count_slow() " UINTX_FORMAT, _container_count, container_count_slow());
805 }
806 #endif
807
808 // BlockFreelist methods
809
810 BlockFreelist::BlockFreelist() : _dictionary(new BlockTreeDictionary()) {}
811
812 BlockFreelist::~BlockFreelist() {
813 delete _dictionary;
814 }
815
816 void BlockFreelist::return_block(MetaWord* p, size_t word_size) {
817 Metablock* free_chunk = ::new (p) Metablock(word_size);
818 dictionary()->return_chunk(free_chunk);
819 }
820
821 MetaWord* BlockFreelist::get_block(size_t word_size) {
822 if (word_size < TreeChunk<Metablock, FreeList<Metablock> >::min_size()) {
823 // Dark matter. Too small for dictionary.
824 return NULL;
825 }
826
827 Metablock* free_block =
828 dictionary()->get_chunk(word_size, FreeBlockDictionary<Metablock>::atLeast);
829 if (free_block == NULL) {
830 return NULL;
831 }
832
833 const size_t block_size = free_block->size();
834 if (block_size > WasteMultiplier * word_size) {
835 return_block((MetaWord*)free_block, block_size);
836 return NULL;
837 }
838
839 MetaWord* new_block = (MetaWord*)free_block;
840 assert(block_size >= word_size, "Incorrect size of block from freelist");
841 const size_t unused = block_size - word_size;
842 if (unused >= TreeChunk<Metablock, FreeList<Metablock> >::min_size()) {
843 return_block(new_block + word_size, unused);
844 }
845
846 return new_block;
847 }
848
849 void BlockFreelist::print_on(outputStream* st) const {
850 dictionary()->print_free_lists(st);
851 }
852
853 // VirtualSpaceNode methods
854
855 VirtualSpaceNode::~VirtualSpaceNode() {
856 _rs.release();
857 #ifdef ASSERT
858 size_t word_size = sizeof(*this) / BytesPerWord;
859 Copy::fill_to_words((HeapWord*) this, word_size, 0xf1f1f1f1);
860 #endif
861 }
862
863 size_t VirtualSpaceNode::used_words_in_vs() const {
864 return pointer_delta(top(), bottom(), sizeof(MetaWord));
865 }
866
867 // Space committed in the VirtualSpace
868 size_t VirtualSpaceNode::capacity_words_in_vs() const {
869 return pointer_delta(end(), bottom(), sizeof(MetaWord));
870 }
871
872 size_t VirtualSpaceNode::free_words_in_vs() const {
873 return pointer_delta(end(), top(), sizeof(MetaWord));
874 }
875
876 // Allocates the chunk from the virtual space only.
877 // This interface is also used internally for debugging. Not all
878 // chunks removed here are necessarily used for allocation.
879 Metachunk* VirtualSpaceNode::take_from_committed(size_t chunk_word_size) {
880 // Bottom of the new chunk
881 MetaWord* chunk_limit = top();
882 assert(chunk_limit != NULL, "Not safe to call this method");
883
884 // The virtual spaces are always expanded by the
885 // commit granularity to enforce the following condition.
886 // Without this the is_available check will not work correctly.
887 assert(_virtual_space.committed_size() == _virtual_space.actual_committed_size(),
888 "The committed memory doesn't match the expanded memory.");
889
890 if (!is_available(chunk_word_size)) {
891 Log(gc, metaspace, freelist) log;
892 log.debug("VirtualSpaceNode::take_from_committed() not available " SIZE_FORMAT " words ", chunk_word_size);
893 // Dump some information about the virtual space that is nearly full
894 ResourceMark rm;
895 print_on(log.debug_stream());
896 return NULL;
897 }
898
899 // Take the space (bump top on the current virtual space).
900 inc_top(chunk_word_size);
901
902 // Initialize the chunk
903 Metachunk* result = ::new (chunk_limit) Metachunk(chunk_word_size, this);
904 return result;
905 }
906
907
908 // Expand the virtual space (commit more of the reserved space)
909 bool VirtualSpaceNode::expand_by(size_t min_words, size_t preferred_words) {
910 size_t min_bytes = min_words * BytesPerWord;
911 size_t preferred_bytes = preferred_words * BytesPerWord;
912
913 size_t uncommitted = virtual_space()->reserved_size() - virtual_space()->actual_committed_size();
914
915 if (uncommitted < min_bytes) {
916 return false;
917 }
918
919 size_t commit = MIN2(preferred_bytes, uncommitted);
920 bool result = virtual_space()->expand_by(commit, false);
921
922 assert(result, "Failed to commit memory");
923
924 return result;
925 }
926
927 Metachunk* VirtualSpaceNode::get_chunk_vs(size_t chunk_word_size) {
928 assert_lock_strong(SpaceManager::expand_lock());
929 Metachunk* result = take_from_committed(chunk_word_size);
930 if (result != NULL) {
931 inc_container_count();
932 }
933 return result;
934 }
935
936 bool VirtualSpaceNode::initialize() {
937
938 if (!_rs.is_reserved()) {
939 return false;
940 }
941
942 // These are necessary restriction to make sure that the virtual space always
943 // grows in steps of Metaspace::commit_alignment(). If both base and size are
944 // aligned only the middle alignment of the VirtualSpace is used.
945 assert_is_ptr_aligned(_rs.base(), Metaspace::commit_alignment());
946 assert_is_size_aligned(_rs.size(), Metaspace::commit_alignment());
947
948 // ReservedSpaces marked as special will have the entire memory
949 // pre-committed. Setting a committed size will make sure that
950 // committed_size and actual_committed_size agrees.
951 size_t pre_committed_size = _rs.special() ? _rs.size() : 0;
952
953 bool result = virtual_space()->initialize_with_granularity(_rs, pre_committed_size,
954 Metaspace::commit_alignment());
955 if (result) {
956 assert(virtual_space()->committed_size() == virtual_space()->actual_committed_size(),
957 "Checking that the pre-committed memory was registered by the VirtualSpace");
958
959 set_top((MetaWord*)virtual_space()->low());
960 set_reserved(MemRegion((HeapWord*)_rs.base(),
961 (HeapWord*)(_rs.base() + _rs.size())));
962
963 assert(reserved()->start() == (HeapWord*) _rs.base(),
964 "Reserved start was not set properly " PTR_FORMAT
965 " != " PTR_FORMAT, p2i(reserved()->start()), p2i(_rs.base()));
966 assert(reserved()->word_size() == _rs.size() / BytesPerWord,
967 "Reserved size was not set properly " SIZE_FORMAT
968 " != " SIZE_FORMAT, reserved()->word_size(),
969 _rs.size() / BytesPerWord);
970 }
971
972 return result;
973 }
974
975 void VirtualSpaceNode::print_on(outputStream* st) const {
976 size_t used = used_words_in_vs();
977 size_t capacity = capacity_words_in_vs();
978 VirtualSpace* vs = virtual_space();
979 st->print_cr(" space @ " PTR_FORMAT " " SIZE_FORMAT "K, " SIZE_FORMAT_W(3) "%% used "
980 "[" PTR_FORMAT ", " PTR_FORMAT ", "
981 PTR_FORMAT ", " PTR_FORMAT ")",
982 p2i(vs), capacity / K,
983 capacity == 0 ? 0 : used * 100 / capacity,
984 p2i(bottom()), p2i(top()), p2i(end()),
985 p2i(vs->high_boundary()));
986 }
987
988 #ifdef ASSERT
989 void VirtualSpaceNode::mangle() {
990 size_t word_size = capacity_words_in_vs();
991 Copy::fill_to_words((HeapWord*) low(), word_size, 0xf1f1f1f1);
992 }
993 #endif // ASSERT
994
995 // VirtualSpaceList methods
996 // Space allocated from the VirtualSpace
997
998 VirtualSpaceList::~VirtualSpaceList() {
999 VirtualSpaceListIterator iter(virtual_space_list());
1000 while (iter.repeat()) {
1001 VirtualSpaceNode* vsl = iter.get_next();
1002 delete vsl;
1003 }
1004 }
1005
1006 void VirtualSpaceList::inc_reserved_words(size_t v) {
1007 assert_lock_strong(SpaceManager::expand_lock());
1008 _reserved_words = _reserved_words + v;
1009 }
1010 void VirtualSpaceList::dec_reserved_words(size_t v) {
1011 assert_lock_strong(SpaceManager::expand_lock());
1012 _reserved_words = _reserved_words - v;
1013 }
1014
1015 #define assert_committed_below_limit() \
1016 assert(MetaspaceAux::committed_bytes() <= MaxMetaspaceSize, \
1017 "Too much committed memory. Committed: " SIZE_FORMAT \
1018 " limit (MaxMetaspaceSize): " SIZE_FORMAT, \
1019 MetaspaceAux::committed_bytes(), MaxMetaspaceSize);
1020
1021 void VirtualSpaceList::inc_committed_words(size_t v) {
1022 assert_lock_strong(SpaceManager::expand_lock());
1023 _committed_words = _committed_words + v;
1024
1025 assert_committed_below_limit();
1026 }
1027 void VirtualSpaceList::dec_committed_words(size_t v) {
1028 assert_lock_strong(SpaceManager::expand_lock());
1029 _committed_words = _committed_words - v;
1030
1031 assert_committed_below_limit();
1032 }
1033
1034 void VirtualSpaceList::inc_virtual_space_count() {
1035 assert_lock_strong(SpaceManager::expand_lock());
1036 _virtual_space_count++;
1037 }
1038 void VirtualSpaceList::dec_virtual_space_count() {
1039 assert_lock_strong(SpaceManager::expand_lock());
1040 _virtual_space_count--;
1041 }
1042
1043 void ChunkManager::remove_chunk(Metachunk* chunk) {
1044 size_t word_size = chunk->word_size();
1045 ChunkIndex index = list_index(word_size);
1046 if (index != HumongousIndex) {
1047 free_chunks(index)->remove_chunk(chunk);
1048 } else {
1049 humongous_dictionary()->remove_chunk(chunk);
1050 }
1051
1052 // Chunk is being removed from the chunks free list.
1053 dec_free_chunks_total(chunk->word_size());
1054 }
1055
1056 // Walk the list of VirtualSpaceNodes and delete
1057 // nodes with a 0 container_count. Remove Metachunks in
1058 // the node from their respective freelists.
1059 void VirtualSpaceList::purge(ChunkManager* chunk_manager) {
1060 assert(SafepointSynchronize::is_at_safepoint(), "must be called at safepoint for contains to work");
1061 assert_lock_strong(SpaceManager::expand_lock());
1062 // Don't use a VirtualSpaceListIterator because this
1063 // list is being changed and a straightforward use of an iterator is not safe.
1064 VirtualSpaceNode* purged_vsl = NULL;
1065 VirtualSpaceNode* prev_vsl = virtual_space_list();
1066 VirtualSpaceNode* next_vsl = prev_vsl;
1067 while (next_vsl != NULL) {
1068 VirtualSpaceNode* vsl = next_vsl;
1069 DEBUG_ONLY(vsl->verify_container_count();)
1070 next_vsl = vsl->next();
1071 // Don't free the current virtual space since it will likely
1072 // be needed soon.
1073 if (vsl->container_count() == 0 && vsl != current_virtual_space()) {
1074 // Unlink it from the list
1075 if (prev_vsl == vsl) {
1076 // This is the case of the current node being the first node.
1077 assert(vsl == virtual_space_list(), "Expected to be the first node");
1078 set_virtual_space_list(vsl->next());
1079 } else {
1080 prev_vsl->set_next(vsl->next());
1081 }
1082
1083 vsl->purge(chunk_manager);
1084 dec_reserved_words(vsl->reserved_words());
1085 dec_committed_words(vsl->committed_words());
1086 dec_virtual_space_count();
1087 purged_vsl = vsl;
1088 delete vsl;
1089 } else {
1090 prev_vsl = vsl;
1091 }
1092 }
1093 #ifdef ASSERT
1094 if (purged_vsl != NULL) {
1095 // List should be stable enough to use an iterator here.
1096 VirtualSpaceListIterator iter(virtual_space_list());
1097 while (iter.repeat()) {
1098 VirtualSpaceNode* vsl = iter.get_next();
1099 assert(vsl != purged_vsl, "Purge of vsl failed");
1100 }
1101 }
1102 #endif
1103 }
1104
1105
1106 // This function looks at the mmap regions in the metaspace without locking.
1107 // The chunks are added with store ordering and not deleted except for at
1108 // unloading time during a safepoint.
1109 bool VirtualSpaceList::contains(const void* ptr) {
1110 // List should be stable enough to use an iterator here because removing virtual
1111 // space nodes is only allowed at a safepoint.
1112 VirtualSpaceListIterator iter(virtual_space_list());
1113 while (iter.repeat()) {
1114 VirtualSpaceNode* vsn = iter.get_next();
1115 if (vsn->contains(ptr)) {
1116 return true;
1117 }
1118 }
1119 return false;
1120 }
1121
1122 void VirtualSpaceList::retire_current_virtual_space() {
1123 assert_lock_strong(SpaceManager::expand_lock());
1124
1125 VirtualSpaceNode* vsn = current_virtual_space();
1126
1127 ChunkManager* cm = is_class() ? Metaspace::chunk_manager_class() :
1128 Metaspace::chunk_manager_metadata();
1129
1130 vsn->retire(cm);
1131 }
1132
1133 void VirtualSpaceNode::retire(ChunkManager* chunk_manager) {
1134 DEBUG_ONLY(verify_container_count();)
1135 for (int i = (int)MediumIndex; i >= (int)ZeroIndex; --i) {
1136 ChunkIndex index = (ChunkIndex)i;
1137 size_t chunk_size = chunk_manager->free_chunks(index)->size();
1138
1139 while (free_words_in_vs() >= chunk_size) {
1140 Metachunk* chunk = get_chunk_vs(chunk_size);
1141 assert(chunk != NULL, "allocation should have been successful");
1142
1143 chunk_manager->return_chunks(index, chunk);
1144 chunk_manager->inc_free_chunks_total(chunk_size);
1145 }
1146 DEBUG_ONLY(verify_container_count();)
1147 }
1148 assert(free_words_in_vs() == 0, "should be empty now");
1149 }
1150
1151 VirtualSpaceList::VirtualSpaceList(size_t word_size) :
1152 _is_class(false),
1153 _virtual_space_list(NULL),
1154 _current_virtual_space(NULL),
1155 _reserved_words(0),
1156 _committed_words(0),
1157 _virtual_space_count(0) {
1158 MutexLockerEx cl(SpaceManager::expand_lock(),
1159 Mutex::_no_safepoint_check_flag);
1160 create_new_virtual_space(word_size);
1161 }
1162
1163 VirtualSpaceList::VirtualSpaceList(ReservedSpace rs) :
1164 _is_class(true),
1165 _virtual_space_list(NULL),
1166 _current_virtual_space(NULL),
1167 _reserved_words(0),
1168 _committed_words(0),
1169 _virtual_space_count(0) {
1170 MutexLockerEx cl(SpaceManager::expand_lock(),
1171 Mutex::_no_safepoint_check_flag);
1172 VirtualSpaceNode* class_entry = new VirtualSpaceNode(rs);
1173 bool succeeded = class_entry->initialize();
1174 if (succeeded) {
1175 link_vs(class_entry);
1176 }
1177 }
1178
1179 size_t VirtualSpaceList::free_bytes() {
1180 return virtual_space_list()->free_words_in_vs() * BytesPerWord;
1181 }
1182
1183 // Allocate another meta virtual space and add it to the list.
1184 bool VirtualSpaceList::create_new_virtual_space(size_t vs_word_size) {
1185 assert_lock_strong(SpaceManager::expand_lock());
1186
1187 if (is_class()) {
1188 assert(false, "We currently don't support more than one VirtualSpace for"
1189 " the compressed class space. The initialization of the"
1190 " CCS uses another code path and should not hit this path.");
1191 return false;
1192 }
1193
1194 if (vs_word_size == 0) {
1195 assert(false, "vs_word_size should always be at least _reserve_alignment large.");
1196 return false;
1197 }
1198
1199 // Reserve the space
1200 size_t vs_byte_size = vs_word_size * BytesPerWord;
1201 assert_is_size_aligned(vs_byte_size, Metaspace::reserve_alignment());
1202
1203 // Allocate the meta virtual space and initialize it.
1204 VirtualSpaceNode* new_entry = new VirtualSpaceNode(vs_byte_size);
1205 if (!new_entry->initialize()) {
1206 delete new_entry;
1207 return false;
1208 } else {
1209 assert(new_entry->reserved_words() == vs_word_size,
1210 "Reserved memory size differs from requested memory size");
1211 // ensure lock-free iteration sees fully initialized node
1212 OrderAccess::storestore();
1213 link_vs(new_entry);
1214 return true;
1215 }
1216 }
1217
1218 void VirtualSpaceList::link_vs(VirtualSpaceNode* new_entry) {
1219 if (virtual_space_list() == NULL) {
1220 set_virtual_space_list(new_entry);
1221 } else {
1222 current_virtual_space()->set_next(new_entry);
1223 }
1224 set_current_virtual_space(new_entry);
1225 inc_reserved_words(new_entry->reserved_words());
1226 inc_committed_words(new_entry->committed_words());
1227 inc_virtual_space_count();
1228 #ifdef ASSERT
1229 new_entry->mangle();
1230 #endif
1231 if (log_is_enabled(Trace, gc, metaspace)) {
1232 Log(gc, metaspace) log;
1233 VirtualSpaceNode* vsl = current_virtual_space();
1234 ResourceMark rm;
1235 vsl->print_on(log.trace_stream());
1236 }
1237 }
1238
1239 bool VirtualSpaceList::expand_node_by(VirtualSpaceNode* node,
1240 size_t min_words,
1241 size_t preferred_words) {
1242 size_t before = node->committed_words();
1243
1244 bool result = node->expand_by(min_words, preferred_words);
1245
1246 size_t after = node->committed_words();
1247
1248 // after and before can be the same if the memory was pre-committed.
1249 assert(after >= before, "Inconsistency");
1250 inc_committed_words(after - before);
1251
1252 return result;
1253 }
1254
1255 bool VirtualSpaceList::expand_by(size_t min_words, size_t preferred_words) {
1256 assert_is_size_aligned(min_words, Metaspace::commit_alignment_words());
1257 assert_is_size_aligned(preferred_words, Metaspace::commit_alignment_words());
1258 assert(min_words <= preferred_words, "Invalid arguments");
1259
1260 if (!MetaspaceGC::can_expand(min_words, this->is_class())) {
1261 return false;
1262 }
1263
1264 size_t allowed_expansion_words = MetaspaceGC::allowed_expansion();
1265 if (allowed_expansion_words < min_words) {
1266 return false;
1267 }
1268
1269 size_t max_expansion_words = MIN2(preferred_words, allowed_expansion_words);
1270
1271 // Commit more memory from the the current virtual space.
1272 bool vs_expanded = expand_node_by(current_virtual_space(),
1273 min_words,
1274 max_expansion_words);
1275 if (vs_expanded) {
1276 return true;
1277 }
1278 retire_current_virtual_space();
1279
1280 // Get another virtual space.
1281 size_t grow_vs_words = MAX2((size_t)VirtualSpaceSize, preferred_words);
1282 grow_vs_words = align_size_up(grow_vs_words, Metaspace::reserve_alignment_words());
1283
1284 if (create_new_virtual_space(grow_vs_words)) {
1285 if (current_virtual_space()->is_pre_committed()) {
1286 // The memory was pre-committed, so we are done here.
1287 assert(min_words <= current_virtual_space()->committed_words(),
1288 "The new VirtualSpace was pre-committed, so it"
1289 "should be large enough to fit the alloc request.");
1290 return true;
1291 }
1292
1293 return expand_node_by(current_virtual_space(),
1294 min_words,
1295 max_expansion_words);
1296 }
1297
1298 return false;
1299 }
1300
1301 Metachunk* VirtualSpaceList::get_new_chunk(size_t word_size,
1302 size_t grow_chunks_by_words,
1303 size_t medium_chunk_bunch) {
1304
1305 // Allocate a chunk out of the current virtual space.
1306 Metachunk* next = current_virtual_space()->get_chunk_vs(grow_chunks_by_words);
1307
1308 if (next != NULL) {
1309 return next;
1310 }
1311
1312 // The expand amount is currently only determined by the requested sizes
1313 // and not how much committed memory is left in the current virtual space.
1314
1315 size_t min_word_size = align_size_up(grow_chunks_by_words, Metaspace::commit_alignment_words());
1316 size_t preferred_word_size = align_size_up(medium_chunk_bunch, Metaspace::commit_alignment_words());
1317 if (min_word_size >= preferred_word_size) {
1318 // Can happen when humongous chunks are allocated.
1319 preferred_word_size = min_word_size;
1320 }
1321
1322 bool expanded = expand_by(min_word_size, preferred_word_size);
1323 if (expanded) {
1324 next = current_virtual_space()->get_chunk_vs(grow_chunks_by_words);
1325 assert(next != NULL, "The allocation was expected to succeed after the expansion");
1326 }
1327
1328 return next;
1329 }
1330
1331 void VirtualSpaceList::print_on(outputStream* st) const {
1332 VirtualSpaceListIterator iter(virtual_space_list());
1333 while (iter.repeat()) {
1334 VirtualSpaceNode* node = iter.get_next();
1335 node->print_on(st);
1336 }
1337 }
1338
1339 // MetaspaceGC methods
1340
1341 // VM_CollectForMetadataAllocation is the vm operation used to GC.
1342 // Within the VM operation after the GC the attempt to allocate the metadata
1343 // should succeed. If the GC did not free enough space for the metaspace
1344 // allocation, the HWM is increased so that another virtualspace will be
1345 // allocated for the metadata. With perm gen the increase in the perm
1346 // gen had bounds, MinMetaspaceExpansion and MaxMetaspaceExpansion. The
1347 // metaspace policy uses those as the small and large steps for the HWM.
1348 //
1349 // After the GC the compute_new_size() for MetaspaceGC is called to
1350 // resize the capacity of the metaspaces. The current implementation
1351 // is based on the flags MinMetaspaceFreeRatio and MaxMetaspaceFreeRatio used
1352 // to resize the Java heap by some GC's. New flags can be implemented
1353 // if really needed. MinMetaspaceFreeRatio is used to calculate how much
1354 // free space is desirable in the metaspace capacity to decide how much
1355 // to increase the HWM. MaxMetaspaceFreeRatio is used to decide how much
1356 // free space is desirable in the metaspace capacity before decreasing
1357 // the HWM.
1358
1359 // Calculate the amount to increase the high water mark (HWM).
1360 // Increase by a minimum amount (MinMetaspaceExpansion) so that
1361 // another expansion is not requested too soon. If that is not
1362 // enough to satisfy the allocation, increase by MaxMetaspaceExpansion.
1363 // If that is still not enough, expand by the size of the allocation
1364 // plus some.
1365 size_t MetaspaceGC::delta_capacity_until_GC(size_t bytes) {
1366 size_t min_delta = MinMetaspaceExpansion;
1367 size_t max_delta = MaxMetaspaceExpansion;
1368 size_t delta = align_size_up(bytes, Metaspace::commit_alignment());
1369
1370 if (delta <= min_delta) {
1371 delta = min_delta;
1372 } else if (delta <= max_delta) {
1373 // Don't want to hit the high water mark on the next
1374 // allocation so make the delta greater than just enough
1375 // for this allocation.
1376 delta = max_delta;
1377 } else {
1378 // This allocation is large but the next ones are probably not
1379 // so increase by the minimum.
1380 delta = delta + min_delta;
1381 }
1382
1383 assert_is_size_aligned(delta, Metaspace::commit_alignment());
1384
1385 return delta;
1386 }
1387
1388 size_t MetaspaceGC::capacity_until_GC() {
1389 size_t value = (size_t)OrderAccess::load_ptr_acquire(&_capacity_until_GC);
1390 assert(value >= MetaspaceSize, "Not initialized properly?");
1391 return value;
1392 }
1393
1394 bool MetaspaceGC::inc_capacity_until_GC(size_t v, size_t* new_cap_until_GC, size_t* old_cap_until_GC) {
1395 assert_is_size_aligned(v, Metaspace::commit_alignment());
1396
1397 size_t capacity_until_GC = (size_t) _capacity_until_GC;
1398 size_t new_value = capacity_until_GC + v;
1399
1400 if (new_value < capacity_until_GC) {
1401 // The addition wrapped around, set new_value to aligned max value.
1402 new_value = align_size_down(max_uintx, Metaspace::commit_alignment());
1403 }
1404
1405 intptr_t expected = (intptr_t) capacity_until_GC;
1406 intptr_t actual = Atomic::cmpxchg_ptr((intptr_t) new_value, &_capacity_until_GC, expected);
1407
1408 if (expected != actual) {
1409 return false;
1410 }
1411
1412 if (new_cap_until_GC != NULL) {
1413 *new_cap_until_GC = new_value;
1414 }
1415 if (old_cap_until_GC != NULL) {
1416 *old_cap_until_GC = capacity_until_GC;
1417 }
1418 return true;
1419 }
1420
1421 size_t MetaspaceGC::dec_capacity_until_GC(size_t v) {
1422 assert_is_size_aligned(v, Metaspace::commit_alignment());
1423
1424 return (size_t)Atomic::add_ptr(-(intptr_t)v, &_capacity_until_GC);
1425 }
1426
1427 void MetaspaceGC::initialize() {
1428 // Set the high-water mark to MaxMetapaceSize during VM initializaton since
1429 // we can't do a GC during initialization.
1430 _capacity_until_GC = MaxMetaspaceSize;
1431 }
1432
1433 void MetaspaceGC::post_initialize() {
1434 // Reset the high-water mark once the VM initialization is done.
1435 _capacity_until_GC = MAX2(MetaspaceAux::committed_bytes(), MetaspaceSize);
1436 }
1437
1438 bool MetaspaceGC::can_expand(size_t word_size, bool is_class) {
1439 // Check if the compressed class space is full.
1440 if (is_class && Metaspace::using_class_space()) {
1441 size_t class_committed = MetaspaceAux::committed_bytes(Metaspace::ClassType);
1442 if (class_committed + word_size * BytesPerWord > CompressedClassSpaceSize) {
1443 return false;
1444 }
1445 }
1446
1447 // Check if the user has imposed a limit on the metaspace memory.
1448 size_t committed_bytes = MetaspaceAux::committed_bytes();
1449 if (committed_bytes + word_size * BytesPerWord > MaxMetaspaceSize) {
1450 return false;
1451 }
1452
1453 return true;
1454 }
1455
1456 size_t MetaspaceGC::allowed_expansion() {
1457 size_t committed_bytes = MetaspaceAux::committed_bytes();
1458 size_t capacity_until_gc = capacity_until_GC();
1459
1460 assert(capacity_until_gc >= committed_bytes,
1461 "capacity_until_gc: " SIZE_FORMAT " < committed_bytes: " SIZE_FORMAT,
1462 capacity_until_gc, committed_bytes);
1463
1464 size_t left_until_max = MaxMetaspaceSize - committed_bytes;
1465 size_t left_until_GC = capacity_until_gc - committed_bytes;
1466 size_t left_to_commit = MIN2(left_until_GC, left_until_max);
1467
1468 return left_to_commit / BytesPerWord;
1469 }
1470
1471 void MetaspaceGC::compute_new_size() {
1472 assert(_shrink_factor <= 100, "invalid shrink factor");
1473 uint current_shrink_factor = _shrink_factor;
1474 _shrink_factor = 0;
1475
1476 // Using committed_bytes() for used_after_gc is an overestimation, since the
1477 // chunk free lists are included in committed_bytes() and the memory in an
1478 // un-fragmented chunk free list is available for future allocations.
1479 // However, if the chunk free lists becomes fragmented, then the memory may
1480 // not be available for future allocations and the memory is therefore "in use".
1481 // Including the chunk free lists in the definition of "in use" is therefore
1482 // necessary. Not including the chunk free lists can cause capacity_until_GC to
1483 // shrink below committed_bytes() and this has caused serious bugs in the past.
1484 const size_t used_after_gc = MetaspaceAux::committed_bytes();
1485 const size_t capacity_until_GC = MetaspaceGC::capacity_until_GC();
1486
1487 const double minimum_free_percentage = MinMetaspaceFreeRatio / 100.0;
1488 const double maximum_used_percentage = 1.0 - minimum_free_percentage;
1489
1490 const double min_tmp = used_after_gc / maximum_used_percentage;
1491 size_t minimum_desired_capacity =
1492 (size_t)MIN2(min_tmp, double(max_uintx));
1493 // Don't shrink less than the initial generation size
1494 minimum_desired_capacity = MAX2(minimum_desired_capacity,
1495 MetaspaceSize);
1496
1497 log_trace(gc, metaspace)("MetaspaceGC::compute_new_size: ");
1498 log_trace(gc, metaspace)(" minimum_free_percentage: %6.2f maximum_used_percentage: %6.2f",
1499 minimum_free_percentage, maximum_used_percentage);
1500 log_trace(gc, metaspace)(" used_after_gc : %6.1fKB", used_after_gc / (double) K);
1501
1502
1503 size_t shrink_bytes = 0;
1504 if (capacity_until_GC < minimum_desired_capacity) {
1505 // If we have less capacity below the metaspace HWM, then
1506 // increment the HWM.
1507 size_t expand_bytes = minimum_desired_capacity - capacity_until_GC;
1508 expand_bytes = align_size_up(expand_bytes, Metaspace::commit_alignment());
1509 // Don't expand unless it's significant
1510 if (expand_bytes >= MinMetaspaceExpansion) {
1511 size_t new_capacity_until_GC = 0;
1512 bool succeeded = MetaspaceGC::inc_capacity_until_GC(expand_bytes, &new_capacity_until_GC);
1513 assert(succeeded, "Should always succesfully increment HWM when at safepoint");
1514
1515 Metaspace::tracer()->report_gc_threshold(capacity_until_GC,
1516 new_capacity_until_GC,
1517 MetaspaceGCThresholdUpdater::ComputeNewSize);
1518 log_trace(gc, metaspace)(" expanding: minimum_desired_capacity: %6.1fKB expand_bytes: %6.1fKB MinMetaspaceExpansion: %6.1fKB new metaspace HWM: %6.1fKB",
1519 minimum_desired_capacity / (double) K,
1520 expand_bytes / (double) K,
1521 MinMetaspaceExpansion / (double) K,
1522 new_capacity_until_GC / (double) K);
1523 }
1524 return;
1525 }
1526
1527 // No expansion, now see if we want to shrink
1528 // We would never want to shrink more than this
1529 assert(capacity_until_GC >= minimum_desired_capacity,
1530 SIZE_FORMAT " >= " SIZE_FORMAT,
1531 capacity_until_GC, minimum_desired_capacity);
1532 size_t max_shrink_bytes = capacity_until_GC - minimum_desired_capacity;
1533
1534 // Should shrinking be considered?
1535 if (MaxMetaspaceFreeRatio < 100) {
1536 const double maximum_free_percentage = MaxMetaspaceFreeRatio / 100.0;
1537 const double minimum_used_percentage = 1.0 - maximum_free_percentage;
1538 const double max_tmp = used_after_gc / minimum_used_percentage;
1539 size_t maximum_desired_capacity = (size_t)MIN2(max_tmp, double(max_uintx));
1540 maximum_desired_capacity = MAX2(maximum_desired_capacity,
1541 MetaspaceSize);
1542 log_trace(gc, metaspace)(" maximum_free_percentage: %6.2f minimum_used_percentage: %6.2f",
1543 maximum_free_percentage, minimum_used_percentage);
1544 log_trace(gc, metaspace)(" minimum_desired_capacity: %6.1fKB maximum_desired_capacity: %6.1fKB",
1545 minimum_desired_capacity / (double) K, maximum_desired_capacity / (double) K);
1546
1547 assert(minimum_desired_capacity <= maximum_desired_capacity,
1548 "sanity check");
1549
1550 if (capacity_until_GC > maximum_desired_capacity) {
1551 // Capacity too large, compute shrinking size
1552 shrink_bytes = capacity_until_GC - maximum_desired_capacity;
1553 // We don't want shrink all the way back to initSize if people call
1554 // System.gc(), because some programs do that between "phases" and then
1555 // we'd just have to grow the heap up again for the next phase. So we
1556 // damp the shrinking: 0% on the first call, 10% on the second call, 40%
1557 // on the third call, and 100% by the fourth call. But if we recompute
1558 // size without shrinking, it goes back to 0%.
1559 shrink_bytes = shrink_bytes / 100 * current_shrink_factor;
1560
1561 shrink_bytes = align_size_down(shrink_bytes, Metaspace::commit_alignment());
1562
1563 assert(shrink_bytes <= max_shrink_bytes,
1564 "invalid shrink size " SIZE_FORMAT " not <= " SIZE_FORMAT,
1565 shrink_bytes, max_shrink_bytes);
1566 if (current_shrink_factor == 0) {
1567 _shrink_factor = 10;
1568 } else {
1569 _shrink_factor = MIN2(current_shrink_factor * 4, (uint) 100);
1570 }
1571 log_trace(gc, metaspace)(" shrinking: initThreshold: %.1fK maximum_desired_capacity: %.1fK",
1572 MetaspaceSize / (double) K, maximum_desired_capacity / (double) K);
1573 log_trace(gc, metaspace)(" shrink_bytes: %.1fK current_shrink_factor: %d new shrink factor: %d MinMetaspaceExpansion: %.1fK",
1574 shrink_bytes / (double) K, current_shrink_factor, _shrink_factor, MinMetaspaceExpansion / (double) K);
1575 }
1576 }
1577
1578 // Don't shrink unless it's significant
1579 if (shrink_bytes >= MinMetaspaceExpansion &&
1580 ((capacity_until_GC - shrink_bytes) >= MetaspaceSize)) {
1581 size_t new_capacity_until_GC = MetaspaceGC::dec_capacity_until_GC(shrink_bytes);
1582 Metaspace::tracer()->report_gc_threshold(capacity_until_GC,
1583 new_capacity_until_GC,
1584 MetaspaceGCThresholdUpdater::ComputeNewSize);
1585 }
1586 }
1587
1588 // Metadebug methods
1589
1590 void Metadebug::init_allocation_fail_alot_count() {
1591 if (MetadataAllocationFailALot) {
1592 _allocation_fail_alot_count =
1593 1+(long)((double)MetadataAllocationFailALotInterval*os::random()/(max_jint+1.0));
1594 }
1595 }
1596
1597 #ifdef ASSERT
1598 bool Metadebug::test_metadata_failure() {
1599 if (MetadataAllocationFailALot &&
1600 Threads::is_vm_complete()) {
1601 if (_allocation_fail_alot_count > 0) {
1602 _allocation_fail_alot_count--;
1603 } else {
1604 log_trace(gc, metaspace, freelist)("Metadata allocation failing for MetadataAllocationFailALot");
1605 init_allocation_fail_alot_count();
1606 return true;
1607 }
1608 }
1609 return false;
1610 }
1611 #endif
1612
1613 // ChunkManager methods
1614
1615 size_t ChunkManager::free_chunks_total_words() {
1616 return _free_chunks_total;
1617 }
1618
1619 size_t ChunkManager::free_chunks_total_bytes() {
1620 return free_chunks_total_words() * BytesPerWord;
1621 }
1622
1623 size_t ChunkManager::free_chunks_count() {
1624 #ifdef ASSERT
1625 if (!UseConcMarkSweepGC && !SpaceManager::expand_lock()->is_locked()) {
1626 MutexLockerEx cl(SpaceManager::expand_lock(),
1627 Mutex::_no_safepoint_check_flag);
1628 // This lock is only needed in debug because the verification
1629 // of the _free_chunks_totals walks the list of free chunks
1630 slow_locked_verify_free_chunks_count();
1631 }
1632 #endif
1633 return _free_chunks_count;
1634 }
1635
1636 void ChunkManager::locked_verify_free_chunks_total() {
1637 assert_lock_strong(SpaceManager::expand_lock());
1638 assert(sum_free_chunks() == _free_chunks_total,
1639 "_free_chunks_total " SIZE_FORMAT " is not the"
1640 " same as sum " SIZE_FORMAT, _free_chunks_total,
1641 sum_free_chunks());
1642 }
1643
1644 void ChunkManager::verify_free_chunks_total() {
1645 MutexLockerEx cl(SpaceManager::expand_lock(),
1646 Mutex::_no_safepoint_check_flag);
1647 locked_verify_free_chunks_total();
1648 }
1649
1650 void ChunkManager::locked_verify_free_chunks_count() {
1651 assert_lock_strong(SpaceManager::expand_lock());
1652 assert(sum_free_chunks_count() == _free_chunks_count,
1653 "_free_chunks_count " SIZE_FORMAT " is not the"
1654 " same as sum " SIZE_FORMAT, _free_chunks_count,
1655 sum_free_chunks_count());
1656 }
1657
1658 void ChunkManager::verify_free_chunks_count() {
1659 #ifdef ASSERT
1660 MutexLockerEx cl(SpaceManager::expand_lock(),
1661 Mutex::_no_safepoint_check_flag);
1662 locked_verify_free_chunks_count();
1663 #endif
1664 }
1665
1666 void ChunkManager::verify() {
1667 MutexLockerEx cl(SpaceManager::expand_lock(),
1668 Mutex::_no_safepoint_check_flag);
1669 locked_verify();
1670 }
1671
1672 void ChunkManager::locked_verify() {
1673 locked_verify_free_chunks_count();
1674 locked_verify_free_chunks_total();
1675 }
1676
1677 void ChunkManager::locked_print_free_chunks(outputStream* st) {
1678 assert_lock_strong(SpaceManager::expand_lock());
1679 st->print_cr("Free chunk total " SIZE_FORMAT " count " SIZE_FORMAT,
1680 _free_chunks_total, _free_chunks_count);
1681 }
1682
1683 void ChunkManager::locked_print_sum_free_chunks(outputStream* st) {
1684 assert_lock_strong(SpaceManager::expand_lock());
1685 st->print_cr("Sum free chunk total " SIZE_FORMAT " count " SIZE_FORMAT,
1686 sum_free_chunks(), sum_free_chunks_count());
1687 }
1688 ChunkList* ChunkManager::free_chunks(ChunkIndex index) {
1689 return &_free_chunks[index];
1690 }
1691
1692 // These methods that sum the free chunk lists are used in printing
1693 // methods that are used in product builds.
1694 size_t ChunkManager::sum_free_chunks() {
1695 assert_lock_strong(SpaceManager::expand_lock());
1696 size_t result = 0;
1697 for (ChunkIndex i = ZeroIndex; i < NumberOfFreeLists; i = next_chunk_index(i)) {
1698 ChunkList* list = free_chunks(i);
1699
1700 if (list == NULL) {
1701 continue;
1702 }
1703
1704 result = result + list->count() * list->size();
1705 }
1706 result = result + humongous_dictionary()->total_size();
1707 return result;
1708 }
1709
1710 size_t ChunkManager::sum_free_chunks_count() {
1711 assert_lock_strong(SpaceManager::expand_lock());
1712 size_t count = 0;
1713 for (ChunkIndex i = ZeroIndex; i < NumberOfFreeLists; i = next_chunk_index(i)) {
1714 ChunkList* list = free_chunks(i);
1715 if (list == NULL) {
1716 continue;
1717 }
1718 count = count + list->count();
1719 }
1720 count = count + humongous_dictionary()->total_free_blocks();
1721 return count;
1722 }
1723
1724 ChunkList* ChunkManager::find_free_chunks_list(size_t word_size) {
1725 ChunkIndex index = list_index(word_size);
1726 assert(index < HumongousIndex, "No humongous list");
1727 return free_chunks(index);
1728 }
1729
1730 Metachunk* ChunkManager::free_chunks_get(size_t word_size) {
1731 assert_lock_strong(SpaceManager::expand_lock());
1732
1733 slow_locked_verify();
1734
1735 Metachunk* chunk = NULL;
1736 if (list_index(word_size) != HumongousIndex) {
1737 ChunkList* free_list = find_free_chunks_list(word_size);
1738 assert(free_list != NULL, "Sanity check");
1739
1740 chunk = free_list->head();
1741
1742 if (chunk == NULL) {
1743 return NULL;
1744 }
1745
1746 // Remove the chunk as the head of the list.
1747 free_list->remove_chunk(chunk);
1748
1749 log_trace(gc, metaspace, freelist)("ChunkManager::free_chunks_get: free_list " PTR_FORMAT " head " PTR_FORMAT " size " SIZE_FORMAT,
1750 p2i(free_list), p2i(chunk), chunk->word_size());
1751 } else {
1752 chunk = humongous_dictionary()->get_chunk(
1753 word_size,
1754 FreeBlockDictionary<Metachunk>::atLeast);
1755
1756 if (chunk == NULL) {
1757 return NULL;
1758 }
1759
1760 log_debug(gc, metaspace, alloc)("Free list allocate humongous chunk size " SIZE_FORMAT " for requested size " SIZE_FORMAT " waste " SIZE_FORMAT,
1761 chunk->word_size(), word_size, chunk->word_size() - word_size);
1762 }
1763
1764 // Chunk is being removed from the chunks free list.
1765 dec_free_chunks_total(chunk->word_size());
1766
1767 // Remove it from the links to this freelist
1768 chunk->set_next(NULL);
1769 chunk->set_prev(NULL);
1770 #ifdef ASSERT
1771 // Chunk is no longer on any freelist. Setting to false make container_count_slow()
1772 // work.
1773 chunk->set_is_tagged_free(false);
1774 #endif
1775 chunk->container()->inc_container_count();
1776
1777 slow_locked_verify();
1778 return chunk;
1779 }
1780
1781 Metachunk* ChunkManager::chunk_freelist_allocate(size_t word_size) {
1782 assert_lock_strong(SpaceManager::expand_lock());
1783 slow_locked_verify();
1784
1785 // Take from the beginning of the list
1786 Metachunk* chunk = free_chunks_get(word_size);
1787 if (chunk == NULL) {
1788 return NULL;
1789 }
1790
1791 assert((word_size <= chunk->word_size()) ||
1792 list_index(chunk->word_size() == HumongousIndex),
1793 "Non-humongous variable sized chunk");
1794 Log(gc, metaspace, freelist) log;
1795 if (log.is_debug()) {
1796 size_t list_count;
1797 if (list_index(word_size) < HumongousIndex) {
1798 ChunkList* list = find_free_chunks_list(word_size);
1799 list_count = list->count();
1800 } else {
1801 list_count = humongous_dictionary()->total_count();
1802 }
1803 log.debug("ChunkManager::chunk_freelist_allocate: " PTR_FORMAT " chunk " PTR_FORMAT " size " SIZE_FORMAT " count " SIZE_FORMAT " ",
1804 p2i(this), p2i(chunk), chunk->word_size(), list_count);
1805 ResourceMark rm;
1806 locked_print_free_chunks(log.debug_stream());
1807 }
1808
1809 return chunk;
1810 }
1811
1812 void ChunkManager::print_on(outputStream* out) const {
1813 const_cast<ChunkManager *>(this)->humongous_dictionary()->report_statistics(out);
1814 }
1815
1816 // SpaceManager methods
1817
1818 void SpaceManager::get_initial_chunk_sizes(Metaspace::MetaspaceType type,
1819 size_t* chunk_word_size,
1820 size_t* class_chunk_word_size) {
1821 switch (type) {
1822 case Metaspace::BootMetaspaceType:
1823 *chunk_word_size = Metaspace::first_chunk_word_size();
1824 *class_chunk_word_size = Metaspace::first_class_chunk_word_size();
1825 break;
1826 case Metaspace::ROMetaspaceType:
1827 *chunk_word_size = SharedReadOnlySize / wordSize;
1828 *class_chunk_word_size = ClassSpecializedChunk;
1829 break;
1830 case Metaspace::ReadWriteMetaspaceType:
1831 *chunk_word_size = SharedReadWriteSize / wordSize;
1832 *class_chunk_word_size = ClassSpecializedChunk;
1833 break;
1834 case Metaspace::AnonymousMetaspaceType:
1835 case Metaspace::ReflectionMetaspaceType:
1836 *chunk_word_size = SpecializedChunk;
1837 *class_chunk_word_size = ClassSpecializedChunk;
1838 break;
1839 default:
1840 *chunk_word_size = SmallChunk;
1841 *class_chunk_word_size = ClassSmallChunk;
1842 break;
1843 }
1844 assert(*chunk_word_size != 0 && *class_chunk_word_size != 0,
1845 "Initial chunks sizes bad: data " SIZE_FORMAT
1846 " class " SIZE_FORMAT,
1847 *chunk_word_size, *class_chunk_word_size);
1848 }
1849
1850 size_t SpaceManager::sum_free_in_chunks_in_use() const {
1851 MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag);
1852 size_t free = 0;
1853 for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) {
1854 Metachunk* chunk = chunks_in_use(i);
1855 while (chunk != NULL) {
1856 free += chunk->free_word_size();
1857 chunk = chunk->next();
1858 }
1859 }
1860 return free;
1861 }
1862
1863 size_t SpaceManager::sum_waste_in_chunks_in_use() const {
1864 MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag);
1865 size_t result = 0;
1866 for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) {
1867 result += sum_waste_in_chunks_in_use(i);
1868 }
1869
1870 return result;
1871 }
1872
1873 size_t SpaceManager::sum_waste_in_chunks_in_use(ChunkIndex index) const {
1874 size_t result = 0;
1875 Metachunk* chunk = chunks_in_use(index);
1876 // Count the free space in all the chunk but not the
1877 // current chunk from which allocations are still being done.
1878 while (chunk != NULL) {
1879 if (chunk != current_chunk()) {
1880 result += chunk->free_word_size();
1881 }
1882 chunk = chunk->next();
1883 }
1884 return result;
1885 }
1886
1887 size_t SpaceManager::sum_capacity_in_chunks_in_use() const {
1888 // For CMS use "allocated_chunks_words()" which does not need the
1889 // Metaspace lock. For the other collectors sum over the
1890 // lists. Use both methods as a check that "allocated_chunks_words()"
1891 // is correct. That is, sum_capacity_in_chunks() is too expensive
1892 // to use in the product and allocated_chunks_words() should be used
1893 // but allow for checking that allocated_chunks_words() returns the same
1894 // value as sum_capacity_in_chunks_in_use() which is the definitive
1895 // answer.
1896 if (UseConcMarkSweepGC) {
1897 return allocated_chunks_words();
1898 } else {
1899 MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag);
1900 size_t sum = 0;
1901 for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) {
1902 Metachunk* chunk = chunks_in_use(i);
1903 while (chunk != NULL) {
1904 sum += chunk->word_size();
1905 chunk = chunk->next();
1906 }
1907 }
1908 return sum;
1909 }
1910 }
1911
1912 size_t SpaceManager::sum_count_in_chunks_in_use() {
1913 size_t count = 0;
1914 for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) {
1915 count = count + sum_count_in_chunks_in_use(i);
1916 }
1917
1918 return count;
1919 }
1920
1921 size_t SpaceManager::sum_count_in_chunks_in_use(ChunkIndex i) {
1922 size_t count = 0;
1923 Metachunk* chunk = chunks_in_use(i);
1924 while (chunk != NULL) {
1925 count++;
1926 chunk = chunk->next();
1927 }
1928 return count;
1929 }
1930
1931
1932 size_t SpaceManager::sum_used_in_chunks_in_use() const {
1933 MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag);
1934 size_t used = 0;
1935 for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) {
1936 Metachunk* chunk = chunks_in_use(i);
1937 while (chunk != NULL) {
1938 used += chunk->used_word_size();
1939 chunk = chunk->next();
1940 }
1941 }
1942 return used;
1943 }
1944
1945 void SpaceManager::locked_print_chunks_in_use_on(outputStream* st) const {
1946
1947 for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) {
1948 Metachunk* chunk = chunks_in_use(i);
1949 st->print("SpaceManager: %s " PTR_FORMAT,
1950 chunk_size_name(i), p2i(chunk));
1951 if (chunk != NULL) {
1952 st->print_cr(" free " SIZE_FORMAT,
1953 chunk->free_word_size());
1954 } else {
1955 st->cr();
1956 }
1957 }
1958
1959 chunk_manager()->locked_print_free_chunks(st);
1960 chunk_manager()->locked_print_sum_free_chunks(st);
1961 }
1962
1963 size_t SpaceManager::calc_chunk_size(size_t word_size) {
1964
1965 // Decide between a small chunk and a medium chunk. Up to
1966 // _small_chunk_limit small chunks can be allocated.
1967 // After that a medium chunk is preferred.
1968 size_t chunk_word_size;
1969 if (chunks_in_use(MediumIndex) == NULL &&
1970 sum_count_in_chunks_in_use(SmallIndex) < _small_chunk_limit) {
1971 chunk_word_size = (size_t) small_chunk_size();
1972 if (word_size + Metachunk::overhead() > small_chunk_size()) {
1973 chunk_word_size = medium_chunk_size();
1974 }
1975 } else {
1976 chunk_word_size = medium_chunk_size();
1977 }
1978
1979 // Might still need a humongous chunk. Enforce
1980 // humongous allocations sizes to be aligned up to
1981 // the smallest chunk size.
1982 size_t if_humongous_sized_chunk =
1983 align_size_up(word_size + Metachunk::overhead(),
1984 smallest_chunk_size());
1985 chunk_word_size =
1986 MAX2((size_t) chunk_word_size, if_humongous_sized_chunk);
1987
1988 assert(!SpaceManager::is_humongous(word_size) ||
1989 chunk_word_size == if_humongous_sized_chunk,
1990 "Size calculation is wrong, word_size " SIZE_FORMAT
1991 " chunk_word_size " SIZE_FORMAT,
1992 word_size, chunk_word_size);
1993 Log(gc, metaspace, alloc) log;
1994 if (log.is_debug() && SpaceManager::is_humongous(word_size)) {
1995 log.debug("Metadata humongous allocation:");
1996 log.debug(" word_size " PTR_FORMAT, word_size);
1997 log.debug(" chunk_word_size " PTR_FORMAT, chunk_word_size);
1998 log.debug(" chunk overhead " PTR_FORMAT, Metachunk::overhead());
1999 }
2000 return chunk_word_size;
2001 }
2002
2003 void SpaceManager::track_metaspace_memory_usage() {
2004 if (is_init_completed()) {
2005 if (is_class()) {
2006 MemoryService::track_compressed_class_memory_usage();
2007 }
2008 MemoryService::track_metaspace_memory_usage();
2009 }
2010 }
2011
2012 MetaWord* SpaceManager::grow_and_allocate(size_t word_size) {
2013 assert(vs_list()->current_virtual_space() != NULL,
2014 "Should have been set");
2015 assert(current_chunk() == NULL ||
2016 current_chunk()->allocate(word_size) == NULL,
2017 "Don't need to expand");
2018 MutexLockerEx cl(SpaceManager::expand_lock(), Mutex::_no_safepoint_check_flag);
2019
2020 if (log_is_enabled(Trace, gc, metaspace, freelist)) {
2021 size_t words_left = 0;
2022 size_t words_used = 0;
2023 if (current_chunk() != NULL) {
2024 words_left = current_chunk()->free_word_size();
2025 words_used = current_chunk()->used_word_size();
2026 }
2027 log_trace(gc, metaspace, freelist)("SpaceManager::grow_and_allocate for " SIZE_FORMAT " words " SIZE_FORMAT " words used " SIZE_FORMAT " words left",
2028 word_size, words_used, words_left);
2029 }
2030
2031 // Get another chunk
2032 size_t grow_chunks_by_words = calc_chunk_size(word_size);
2033 Metachunk* next = get_new_chunk(word_size, grow_chunks_by_words);
2034
2035 MetaWord* mem = NULL;
2036
2037 // If a chunk was available, add it to the in-use chunk list
2038 // and do an allocation from it.
2039 if (next != NULL) {
2040 // Add to this manager's list of chunks in use.
2041 add_chunk(next, false);
2042 mem = next->allocate(word_size);
2043 }
2044
2045 // Track metaspace memory usage statistic.
2046 track_metaspace_memory_usage();
2047
2048 return mem;
2049 }
2050
2051 void SpaceManager::print_on(outputStream* st) const {
2052
2053 for (ChunkIndex i = ZeroIndex;
2054 i < NumberOfInUseLists ;
2055 i = next_chunk_index(i) ) {
2056 st->print_cr(" chunks_in_use " PTR_FORMAT " chunk size " SIZE_FORMAT,
2057 p2i(chunks_in_use(i)),
2058 chunks_in_use(i) == NULL ? 0 : chunks_in_use(i)->word_size());
2059 }
2060 st->print_cr(" waste: Small " SIZE_FORMAT " Medium " SIZE_FORMAT
2061 " Humongous " SIZE_FORMAT,
2062 sum_waste_in_chunks_in_use(SmallIndex),
2063 sum_waste_in_chunks_in_use(MediumIndex),
2064 sum_waste_in_chunks_in_use(HumongousIndex));
2065 // block free lists
2066 if (block_freelists() != NULL) {
2067 st->print_cr("total in block free lists " SIZE_FORMAT,
2068 block_freelists()->total_size());
2069 }
2070 }
2071
2072 SpaceManager::SpaceManager(Metaspace::MetadataType mdtype,
2073 Mutex* lock) :
2074 _mdtype(mdtype),
2075 _allocated_blocks_words(0),
2076 _allocated_chunks_words(0),
2077 _allocated_chunks_count(0),
2078 _lock(lock)
2079 {
2080 initialize();
2081 }
2082
2083 void SpaceManager::inc_size_metrics(size_t words) {
2084 assert_lock_strong(SpaceManager::expand_lock());
2085 // Total of allocated Metachunks and allocated Metachunks count
2086 // for each SpaceManager
2087 _allocated_chunks_words = _allocated_chunks_words + words;
2088 _allocated_chunks_count++;
2089 // Global total of capacity in allocated Metachunks
2090 MetaspaceAux::inc_capacity(mdtype(), words);
2091 // Global total of allocated Metablocks.
2092 // used_words_slow() includes the overhead in each
2093 // Metachunk so include it in the used when the
2094 // Metachunk is first added (so only added once per
2095 // Metachunk).
2096 MetaspaceAux::inc_used(mdtype(), Metachunk::overhead());
2097 }
2098
2099 void SpaceManager::inc_used_metrics(size_t words) {
2100 // Add to the per SpaceManager total
2101 Atomic::add_ptr(words, &_allocated_blocks_words);
2102 // Add to the global total
2103 MetaspaceAux::inc_used(mdtype(), words);
2104 }
2105
2106 void SpaceManager::dec_total_from_size_metrics() {
2107 MetaspaceAux::dec_capacity(mdtype(), allocated_chunks_words());
2108 MetaspaceAux::dec_used(mdtype(), allocated_blocks_words());
2109 // Also deduct the overhead per Metachunk
2110 MetaspaceAux::dec_used(mdtype(), allocated_chunks_count() * Metachunk::overhead());
2111 }
2112
2113 void SpaceManager::initialize() {
2114 Metadebug::init_allocation_fail_alot_count();
2115 for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) {
2116 _chunks_in_use[i] = NULL;
2117 }
2118 _current_chunk = NULL;
2119 log_trace(gc, metaspace, freelist)("SpaceManager(): " PTR_FORMAT, p2i(this));
2120 }
2121
2122 void ChunkManager::return_chunks(ChunkIndex index, Metachunk* chunks) {
2123 if (chunks == NULL) {
2124 return;
2125 }
2126 ChunkList* list = free_chunks(index);
2127 assert(list->size() == chunks->word_size(), "Mismatch in chunk sizes");
2128 assert_lock_strong(SpaceManager::expand_lock());
2129 Metachunk* cur = chunks;
2130
2131 // This returns chunks one at a time. If a new
2132 // class List can be created that is a base class
2133 // of FreeList then something like FreeList::prepend()
2134 // can be used in place of this loop
2135 while (cur != NULL) {
2136 assert(cur->container() != NULL, "Container should have been set");
2137 cur->container()->dec_container_count();
2138 // Capture the next link before it is changed
2139 // by the call to return_chunk_at_head();
2140 Metachunk* next = cur->next();
2141 DEBUG_ONLY(cur->set_is_tagged_free(true);)
2142 NOT_PRODUCT(cur->mangle(badMetaWordVal);)
2143 list->return_chunk_at_head(cur);
2144 cur = next;
2145 }
2146 }
2147
2148 SpaceManager::~SpaceManager() {
2149 // This call this->_lock which can't be done while holding expand_lock()
2150 assert(sum_capacity_in_chunks_in_use() == allocated_chunks_words(),
2151 "sum_capacity_in_chunks_in_use() " SIZE_FORMAT
2152 " allocated_chunks_words() " SIZE_FORMAT,
2153 sum_capacity_in_chunks_in_use(), allocated_chunks_words());
2154
2155 MutexLockerEx fcl(SpaceManager::expand_lock(),
2156 Mutex::_no_safepoint_check_flag);
2157
2158 chunk_manager()->slow_locked_verify();
2159
2160 dec_total_from_size_metrics();
2161
2162 Log(gc, metaspace, freelist) log;
2163 if (log.is_trace()) {
2164 log.trace("~SpaceManager(): " PTR_FORMAT, p2i(this));
2165 ResourceMark rm;
2166 locked_print_chunks_in_use_on(log.trace_stream());
2167 block_freelists()->print_on(log.trace_stream());
2168 }
2169
2170 // Have to update before the chunks_in_use lists are emptied
2171 // below.
2172 chunk_manager()->inc_free_chunks_total(allocated_chunks_words(),
2173 sum_count_in_chunks_in_use());
2174
2175 // Add all the chunks in use by this space manager
2176 // to the global list of free chunks.
2177
2178 // Follow each list of chunks-in-use and add them to the
2179 // free lists. Each list is NULL terminated.
2180
2181 for (ChunkIndex i = ZeroIndex; i < HumongousIndex; i = next_chunk_index(i)) {
2182 log.trace("returned " SIZE_FORMAT " %s chunks to freelist", sum_count_in_chunks_in_use(i), chunk_size_name(i));
2183 Metachunk* chunks = chunks_in_use(i);
2184 chunk_manager()->return_chunks(i, chunks);
2185 set_chunks_in_use(i, NULL);
2186 log.trace("updated freelist count " SSIZE_FORMAT " %s", chunk_manager()->free_chunks(i)->count(), chunk_size_name(i));
2187 assert(i != HumongousIndex, "Humongous chunks are handled explicitly later");
2188 }
2189
2190 // The medium chunk case may be optimized by passing the head and
2191 // tail of the medium chunk list to add_at_head(). The tail is often
2192 // the current chunk but there are probably exceptions.
2193
2194 // Humongous chunks
2195 log.trace("returned " SIZE_FORMAT " %s humongous chunks to dictionary",
2196 sum_count_in_chunks_in_use(HumongousIndex), chunk_size_name(HumongousIndex));
2197 log.trace("Humongous chunk dictionary: ");
2198 // Humongous chunks are never the current chunk.
2199 Metachunk* humongous_chunks = chunks_in_use(HumongousIndex);
2200
2201 while (humongous_chunks != NULL) {
2202 DEBUG_ONLY(humongous_chunks->set_is_tagged_free(true);)
2203 NOT_PRODUCT(humongous_chunks->mangle(badMetaWordVal);)
2204 log.trace(PTR_FORMAT " (" SIZE_FORMAT ") ", p2i(humongous_chunks), humongous_chunks->word_size());
2205 assert(humongous_chunks->word_size() == (size_t)
2206 align_size_up(humongous_chunks->word_size(),
2207 smallest_chunk_size()),
2208 "Humongous chunk size is wrong: word size " SIZE_FORMAT
2209 " granularity " SIZE_FORMAT,
2210 humongous_chunks->word_size(), smallest_chunk_size());
2211 Metachunk* next_humongous_chunks = humongous_chunks->next();
2212 humongous_chunks->container()->dec_container_count();
2213 chunk_manager()->humongous_dictionary()->return_chunk(humongous_chunks);
2214 humongous_chunks = next_humongous_chunks;
2215 }
2216 log.trace("updated dictionary count " SIZE_FORMAT " %s", chunk_manager()->humongous_dictionary()->total_count(), chunk_size_name(HumongousIndex));
2217 chunk_manager()->slow_locked_verify();
2218 }
2219
2220 const char* SpaceManager::chunk_size_name(ChunkIndex index) const {
2221 switch (index) {
2222 case SpecializedIndex:
2223 return "Specialized";
2224 case SmallIndex:
2225 return "Small";
2226 case MediumIndex:
2227 return "Medium";
2228 case HumongousIndex:
2229 return "Humongous";
2230 default:
2231 return NULL;
2232 }
2233 }
2234
2235 ChunkIndex ChunkManager::list_index(size_t size) {
2236 switch (size) {
2237 case SpecializedChunk:
2238 assert(SpecializedChunk == ClassSpecializedChunk,
2239 "Need branch for ClassSpecializedChunk");
2240 return SpecializedIndex;
2241 case SmallChunk:
2242 case ClassSmallChunk:
2243 return SmallIndex;
2244 case MediumChunk:
2245 case ClassMediumChunk:
2246 return MediumIndex;
2247 default:
2248 assert(size > MediumChunk || size > ClassMediumChunk,
2249 "Not a humongous chunk");
2250 return HumongousIndex;
2251 }
2252 }
2253
2254 void SpaceManager::deallocate(MetaWord* p, size_t word_size) {
2255 assert_lock_strong(_lock);
2256 size_t raw_word_size = get_raw_word_size(word_size);
2257 size_t min_size = TreeChunk<Metablock, FreeList<Metablock> >::min_size();
2258 assert(raw_word_size >= min_size,
2259 "Should not deallocate dark matter " SIZE_FORMAT "<" SIZE_FORMAT, word_size, min_size);
2260 block_freelists()->return_block(p, raw_word_size);
2261 }
2262
2263 // Adds a chunk to the list of chunks in use.
2264 void SpaceManager::add_chunk(Metachunk* new_chunk, bool make_current) {
2265
2266 assert(new_chunk != NULL, "Should not be NULL");
2267 assert(new_chunk->next() == NULL, "Should not be on a list");
2268
2269 new_chunk->reset_empty();
2270
2271 // Find the correct list and and set the current
2272 // chunk for that list.
2273 ChunkIndex index = ChunkManager::list_index(new_chunk->word_size());
2274
2275 if (index != HumongousIndex) {
2276 retire_current_chunk();
2277 set_current_chunk(new_chunk);
2278 new_chunk->set_next(chunks_in_use(index));
2279 set_chunks_in_use(index, new_chunk);
2280 } else {
2281 // For null class loader data and DumpSharedSpaces, the first chunk isn't
2282 // small, so small will be null. Link this first chunk as the current
2283 // chunk.
2284 if (make_current) {
2285 // Set as the current chunk but otherwise treat as a humongous chunk.
2286 set_current_chunk(new_chunk);
2287 }
2288 // Link at head. The _current_chunk only points to a humongous chunk for
2289 // the null class loader metaspace (class and data virtual space managers)
2290 // any humongous chunks so will not point to the tail
2291 // of the humongous chunks list.
2292 new_chunk->set_next(chunks_in_use(HumongousIndex));
2293 set_chunks_in_use(HumongousIndex, new_chunk);
2294
2295 assert(new_chunk->word_size() > medium_chunk_size(), "List inconsistency");
2296 }
2297
2298 // Add to the running sum of capacity
2299 inc_size_metrics(new_chunk->word_size());
2300
2301 assert(new_chunk->is_empty(), "Not ready for reuse");
2302 Log(gc, metaspace, freelist) log;
2303 if (log.is_trace()) {
2304 log.trace("SpaceManager::add_chunk: " SIZE_FORMAT ") ", sum_count_in_chunks_in_use());
2305 ResourceMark rm;
2306 outputStream* out = log.trace_stream();
2307 new_chunk->print_on(out);
2308 chunk_manager()->locked_print_free_chunks(out);
2309 }
2310 }
2311
2312 void SpaceManager::retire_current_chunk() {
2313 if (current_chunk() != NULL) {
2314 size_t remaining_words = current_chunk()->free_word_size();
2315 if (remaining_words >= TreeChunk<Metablock, FreeList<Metablock> >::min_size()) {
2316 block_freelists()->return_block(current_chunk()->allocate(remaining_words), remaining_words);
2317 inc_used_metrics(remaining_words);
2318 }
2319 }
2320 }
2321
2322 Metachunk* SpaceManager::get_new_chunk(size_t word_size,
2323 size_t grow_chunks_by_words) {
2324 // Get a chunk from the chunk freelist
2325 Metachunk* next = chunk_manager()->chunk_freelist_allocate(grow_chunks_by_words);
2326
2327 if (next == NULL) {
2328 next = vs_list()->get_new_chunk(word_size,
2329 grow_chunks_by_words,
2330 medium_chunk_bunch());
2331 }
2332
2333 Log(gc, metaspace, alloc) log;
2334 if (log.is_debug() && next != NULL &&
2335 SpaceManager::is_humongous(next->word_size())) {
2336 log.debug(" new humongous chunk word size " PTR_FORMAT, next->word_size());
2337 }
2338
2339 return next;
2340 }
2341
2342 /*
2343 * The policy is to allocate up to _small_chunk_limit small chunks
2344 * after which only medium chunks are allocated. This is done to
2345 * reduce fragmentation. In some cases, this can result in a lot
2346 * of small chunks being allocated to the point where it's not
2347 * possible to expand. If this happens, there may be no medium chunks
2348 * available and OOME would be thrown. Instead of doing that,
2349 * if the allocation request size fits in a small chunk, an attempt
2350 * will be made to allocate a small chunk.
2351 */
2352 MetaWord* SpaceManager::get_small_chunk_and_allocate(size_t word_size) {
2353 size_t raw_word_size = get_raw_word_size(word_size);
2354
2355 if (raw_word_size + Metachunk::overhead() > small_chunk_size()) {
2356 return NULL;
2357 }
2358
2359 MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag);
2360 MutexLockerEx cl1(expand_lock(), Mutex::_no_safepoint_check_flag);
2361
2362 Metachunk* chunk = chunk_manager()->chunk_freelist_allocate(small_chunk_size());
2363
2364 MetaWord* mem = NULL;
2365
2366 if (chunk != NULL) {
2367 // Add chunk to the in-use chunk list and do an allocation from it.
2368 // Add to this manager's list of chunks in use.
2369 add_chunk(chunk, false);
2370 mem = chunk->allocate(raw_word_size);
2371
2372 inc_used_metrics(raw_word_size);
2373
2374 // Track metaspace memory usage statistic.
2375 track_metaspace_memory_usage();
2376 }
2377
2378 return mem;
2379 }
2380
2381 MetaWord* SpaceManager::allocate(size_t word_size) {
2382 MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag);
2383
2384 size_t raw_word_size = get_raw_word_size(word_size);
2385 BlockFreelist* fl = block_freelists();
2386 MetaWord* p = NULL;
2387 // Allocation from the dictionary is expensive in the sense that
2388 // the dictionary has to be searched for a size. Don't allocate
2389 // from the dictionary until it starts to get fat. Is this
2390 // a reasonable policy? Maybe an skinny dictionary is fast enough
2391 // for allocations. Do some profiling. JJJ
2392 if (fl->total_size() > allocation_from_dictionary_limit) {
2393 p = fl->get_block(raw_word_size);
2394 }
2395 if (p == NULL) {
2396 p = allocate_work(raw_word_size);
2397 }
2398
2399 return p;
2400 }
2401
2402 // Returns the address of spaced allocated for "word_size".
2403 // This methods does not know about blocks (Metablocks)
2404 MetaWord* SpaceManager::allocate_work(size_t word_size) {
2405 assert_lock_strong(_lock);
2406 #ifdef ASSERT
2407 if (Metadebug::test_metadata_failure()) {
2408 return NULL;
2409 }
2410 #endif
2411 // Is there space in the current chunk?
2412 MetaWord* result = NULL;
2413
2414 // For DumpSharedSpaces, only allocate out of the current chunk which is
2415 // never null because we gave it the size we wanted. Caller reports out
2416 // of memory if this returns null.
2417 if (DumpSharedSpaces) {
2418 assert(current_chunk() != NULL, "should never happen");
2419 inc_used_metrics(word_size);
2420 return current_chunk()->allocate(word_size); // caller handles null result
2421 }
2422
2423 if (current_chunk() != NULL) {
2424 result = current_chunk()->allocate(word_size);
2425 }
2426
2427 if (result == NULL) {
2428 result = grow_and_allocate(word_size);
2429 }
2430
2431 if (result != NULL) {
2432 inc_used_metrics(word_size);
2433 assert(result != (MetaWord*) chunks_in_use(MediumIndex),
2434 "Head of the list is being allocated");
2435 }
2436
2437 return result;
2438 }
2439
2440 void SpaceManager::verify() {
2441 // If there are blocks in the dictionary, then
2442 // verification of chunks does not work since
2443 // being in the dictionary alters a chunk.
2444 if (block_freelists()->total_size() == 0) {
2445 for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) {
2446 Metachunk* curr = chunks_in_use(i);
2447 while (curr != NULL) {
2448 curr->verify();
2449 verify_chunk_size(curr);
2450 curr = curr->next();
2451 }
2452 }
2453 }
2454 }
2455
2456 void SpaceManager::verify_chunk_size(Metachunk* chunk) {
2457 assert(is_humongous(chunk->word_size()) ||
2458 chunk->word_size() == medium_chunk_size() ||
2459 chunk->word_size() == small_chunk_size() ||
2460 chunk->word_size() == specialized_chunk_size(),
2461 "Chunk size is wrong");
2462 return;
2463 }
2464
2465 #ifdef ASSERT
2466 void SpaceManager::verify_allocated_blocks_words() {
2467 // Verification is only guaranteed at a safepoint.
2468 assert(SafepointSynchronize::is_at_safepoint() || !Universe::is_fully_initialized(),
2469 "Verification can fail if the applications is running");
2470 assert(allocated_blocks_words() == sum_used_in_chunks_in_use(),
2471 "allocation total is not consistent " SIZE_FORMAT
2472 " vs " SIZE_FORMAT,
2473 allocated_blocks_words(), sum_used_in_chunks_in_use());
2474 }
2475
2476 #endif
2477
2478 void SpaceManager::dump(outputStream* const out) const {
2479 size_t curr_total = 0;
2480 size_t waste = 0;
2481 uint i = 0;
2482 size_t used = 0;
2483 size_t capacity = 0;
2484
2485 // Add up statistics for all chunks in this SpaceManager.
2486 for (ChunkIndex index = ZeroIndex;
2487 index < NumberOfInUseLists;
2488 index = next_chunk_index(index)) {
2489 for (Metachunk* curr = chunks_in_use(index);
2490 curr != NULL;
2491 curr = curr->next()) {
2492 out->print("%d) ", i++);
2493 curr->print_on(out);
2494 curr_total += curr->word_size();
2495 used += curr->used_word_size();
2496 capacity += curr->word_size();
2497 waste += curr->free_word_size() + curr->overhead();;
2498 }
2499 }
2500
2501 if (log_is_enabled(Trace, gc, metaspace, freelist)) {
2502 block_freelists()->print_on(out);
2503 }
2504
2505 size_t free = current_chunk() == NULL ? 0 : current_chunk()->free_word_size();
2506 // Free space isn't wasted.
2507 waste -= free;
2508
2509 out->print_cr("total of all chunks " SIZE_FORMAT " used " SIZE_FORMAT
2510 " free " SIZE_FORMAT " capacity " SIZE_FORMAT
2511 " waste " SIZE_FORMAT, curr_total, used, free, capacity, waste);
2512 }
2513
2514 // MetaspaceAux
2515
2516
2517 size_t MetaspaceAux::_capacity_words[] = {0, 0};
2518 size_t MetaspaceAux::_used_words[] = {0, 0};
2519
2520 size_t MetaspaceAux::free_bytes(Metaspace::MetadataType mdtype) {
2521 VirtualSpaceList* list = Metaspace::get_space_list(mdtype);
2522 return list == NULL ? 0 : list->free_bytes();
2523 }
2524
2525 size_t MetaspaceAux::free_bytes() {
2526 return free_bytes(Metaspace::ClassType) + free_bytes(Metaspace::NonClassType);
2527 }
2528
2529 void MetaspaceAux::dec_capacity(Metaspace::MetadataType mdtype, size_t words) {
2530 assert_lock_strong(SpaceManager::expand_lock());
2531 assert(words <= capacity_words(mdtype),
2532 "About to decrement below 0: words " SIZE_FORMAT
2533 " is greater than _capacity_words[%u] " SIZE_FORMAT,
2534 words, mdtype, capacity_words(mdtype));
2535 _capacity_words[mdtype] -= words;
2536 }
2537
2538 void MetaspaceAux::inc_capacity(Metaspace::MetadataType mdtype, size_t words) {
2539 assert_lock_strong(SpaceManager::expand_lock());
2540 // Needs to be atomic
2541 _capacity_words[mdtype] += words;
2542 }
2543
2544 void MetaspaceAux::dec_used(Metaspace::MetadataType mdtype, size_t words) {
2545 assert(words <= used_words(mdtype),
2546 "About to decrement below 0: words " SIZE_FORMAT
2547 " is greater than _used_words[%u] " SIZE_FORMAT,
2548 words, mdtype, used_words(mdtype));
2549 // For CMS deallocation of the Metaspaces occurs during the
2550 // sweep which is a concurrent phase. Protection by the expand_lock()
2551 // is not enough since allocation is on a per Metaspace basis
2552 // and protected by the Metaspace lock.
2553 jlong minus_words = (jlong) - (jlong) words;
2554 Atomic::add_ptr(minus_words, &_used_words[mdtype]);
2555 }
2556
2557 void MetaspaceAux::inc_used(Metaspace::MetadataType mdtype, size_t words) {
2558 // _used_words tracks allocations for
2559 // each piece of metadata. Those allocations are
2560 // generally done concurrently by different application
2561 // threads so must be done atomically.
2562 Atomic::add_ptr(words, &_used_words[mdtype]);
2563 }
2564
2565 size_t MetaspaceAux::used_bytes_slow(Metaspace::MetadataType mdtype) {
2566 size_t used = 0;
2567 ClassLoaderDataGraphMetaspaceIterator iter;
2568 while (iter.repeat()) {
2569 Metaspace* msp = iter.get_next();
2570 // Sum allocated_blocks_words for each metaspace
2571 if (msp != NULL) {
2572 used += msp->used_words_slow(mdtype);
2573 }
2574 }
2575 return used * BytesPerWord;
2576 }
2577
2578 size_t MetaspaceAux::free_bytes_slow(Metaspace::MetadataType mdtype) {
2579 size_t free = 0;
2580 ClassLoaderDataGraphMetaspaceIterator iter;
2581 while (iter.repeat()) {
2582 Metaspace* msp = iter.get_next();
2583 if (msp != NULL) {
2584 free += msp->free_words_slow(mdtype);
2585 }
2586 }
2587 return free * BytesPerWord;
2588 }
2589
2590 size_t MetaspaceAux::capacity_bytes_slow(Metaspace::MetadataType mdtype) {
2591 if ((mdtype == Metaspace::ClassType) && !Metaspace::using_class_space()) {
2592 return 0;
2593 }
2594 // Don't count the space in the freelists. That space will be
2595 // added to the capacity calculation as needed.
2596 size_t capacity = 0;
2597 ClassLoaderDataGraphMetaspaceIterator iter;
2598 while (iter.repeat()) {
2599 Metaspace* msp = iter.get_next();
2600 if (msp != NULL) {
2601 capacity += msp->capacity_words_slow(mdtype);
2602 }
2603 }
2604 return capacity * BytesPerWord;
2605 }
2606
2607 size_t MetaspaceAux::capacity_bytes_slow() {
2608 #ifdef PRODUCT
2609 // Use capacity_bytes() in PRODUCT instead of this function.
2610 guarantee(false, "Should not call capacity_bytes_slow() in the PRODUCT");
2611 #endif
2612 size_t class_capacity = capacity_bytes_slow(Metaspace::ClassType);
2613 size_t non_class_capacity = capacity_bytes_slow(Metaspace::NonClassType);
2614 assert(capacity_bytes() == class_capacity + non_class_capacity,
2615 "bad accounting: capacity_bytes() " SIZE_FORMAT
2616 " class_capacity + non_class_capacity " SIZE_FORMAT
2617 " class_capacity " SIZE_FORMAT " non_class_capacity " SIZE_FORMAT,
2618 capacity_bytes(), class_capacity + non_class_capacity,
2619 class_capacity, non_class_capacity);
2620
2621 return class_capacity + non_class_capacity;
2622 }
2623
2624 size_t MetaspaceAux::reserved_bytes(Metaspace::MetadataType mdtype) {
2625 VirtualSpaceList* list = Metaspace::get_space_list(mdtype);
2626 return list == NULL ? 0 : list->reserved_bytes();
2627 }
2628
2629 size_t MetaspaceAux::committed_bytes(Metaspace::MetadataType mdtype) {
2630 VirtualSpaceList* list = Metaspace::get_space_list(mdtype);
2631 return list == NULL ? 0 : list->committed_bytes();
2632 }
2633
2634 size_t MetaspaceAux::min_chunk_size_words() { return Metaspace::first_chunk_word_size(); }
2635
2636 size_t MetaspaceAux::free_chunks_total_words(Metaspace::MetadataType mdtype) {
2637 ChunkManager* chunk_manager = Metaspace::get_chunk_manager(mdtype);
2638 if (chunk_manager == NULL) {
2639 return 0;
2640 }
2641 chunk_manager->slow_verify();
2642 return chunk_manager->free_chunks_total_words();
2643 }
2644
2645 size_t MetaspaceAux::free_chunks_total_bytes(Metaspace::MetadataType mdtype) {
2646 return free_chunks_total_words(mdtype) * BytesPerWord;
2647 }
2648
2649 size_t MetaspaceAux::free_chunks_total_words() {
2650 return free_chunks_total_words(Metaspace::ClassType) +
2651 free_chunks_total_words(Metaspace::NonClassType);
2652 }
2653
2654 size_t MetaspaceAux::free_chunks_total_bytes() {
2655 return free_chunks_total_words() * BytesPerWord;
2656 }
2657
2658 bool MetaspaceAux::has_chunk_free_list(Metaspace::MetadataType mdtype) {
2659 return Metaspace::get_chunk_manager(mdtype) != NULL;
2660 }
2661
2662 MetaspaceChunkFreeListSummary MetaspaceAux::chunk_free_list_summary(Metaspace::MetadataType mdtype) {
2663 if (!has_chunk_free_list(mdtype)) {
2664 return MetaspaceChunkFreeListSummary();
2665 }
2666
2667 const ChunkManager* cm = Metaspace::get_chunk_manager(mdtype);
2668 return cm->chunk_free_list_summary();
2669 }
2670
2671 void MetaspaceAux::print_metaspace_change(size_t prev_metadata_used) {
2672 log_info(gc, metaspace)("Metaspace: " SIZE_FORMAT "K->" SIZE_FORMAT "K(" SIZE_FORMAT "K)",
2673 prev_metadata_used/K, used_bytes()/K, reserved_bytes()/K);
2674 }
2675
2676 void MetaspaceAux::print_on(outputStream* out) {
2677 Metaspace::MetadataType nct = Metaspace::NonClassType;
2678
2679 out->print_cr(" Metaspace "
2680 "used " SIZE_FORMAT "K, "
2681 "capacity " SIZE_FORMAT "K, "
2682 "committed " SIZE_FORMAT "K, "
2683 "reserved " SIZE_FORMAT "K",
2684 used_bytes()/K,
2685 capacity_bytes()/K,
2686 committed_bytes()/K,
2687 reserved_bytes()/K);
2688
2689 if (Metaspace::using_class_space()) {
2690 Metaspace::MetadataType ct = Metaspace::ClassType;
2691 out->print_cr(" class space "
2692 "used " SIZE_FORMAT "K, "
2693 "capacity " SIZE_FORMAT "K, "
2694 "committed " SIZE_FORMAT "K, "
2695 "reserved " SIZE_FORMAT "K",
2696 used_bytes(ct)/K,
2697 capacity_bytes(ct)/K,
2698 committed_bytes(ct)/K,
2699 reserved_bytes(ct)/K);
2700 }
2701 }
2702
2703 // Print information for class space and data space separately.
2704 // This is almost the same as above.
2705 void MetaspaceAux::print_on(outputStream* out, Metaspace::MetadataType mdtype) {
2706 size_t free_chunks_capacity_bytes = free_chunks_total_bytes(mdtype);
2707 size_t capacity_bytes = capacity_bytes_slow(mdtype);
2708 size_t used_bytes = used_bytes_slow(mdtype);
2709 size_t free_bytes = free_bytes_slow(mdtype);
2710 size_t used_and_free = used_bytes + free_bytes +
2711 free_chunks_capacity_bytes;
2712 out->print_cr(" Chunk accounting: used in chunks " SIZE_FORMAT
2713 "K + unused in chunks " SIZE_FORMAT "K + "
2714 " capacity in free chunks " SIZE_FORMAT "K = " SIZE_FORMAT
2715 "K capacity in allocated chunks " SIZE_FORMAT "K",
2716 used_bytes / K,
2717 free_bytes / K,
2718 free_chunks_capacity_bytes / K,
2719 used_and_free / K,
2720 capacity_bytes / K);
2721 // Accounting can only be correct if we got the values during a safepoint
2722 assert(!SafepointSynchronize::is_at_safepoint() || used_and_free == capacity_bytes, "Accounting is wrong");
2723 }
2724
2725 // Print total fragmentation for class metaspaces
2726 void MetaspaceAux::print_class_waste(outputStream* out) {
2727 assert(Metaspace::using_class_space(), "class metaspace not used");
2728 size_t cls_specialized_waste = 0, cls_small_waste = 0, cls_medium_waste = 0;
2729 size_t cls_specialized_count = 0, cls_small_count = 0, cls_medium_count = 0, cls_humongous_count = 0;
2730 ClassLoaderDataGraphMetaspaceIterator iter;
2731 while (iter.repeat()) {
2732 Metaspace* msp = iter.get_next();
2733 if (msp != NULL) {
2734 cls_specialized_waste += msp->class_vsm()->sum_waste_in_chunks_in_use(SpecializedIndex);
2735 cls_specialized_count += msp->class_vsm()->sum_count_in_chunks_in_use(SpecializedIndex);
2736 cls_small_waste += msp->class_vsm()->sum_waste_in_chunks_in_use(SmallIndex);
2737 cls_small_count += msp->class_vsm()->sum_count_in_chunks_in_use(SmallIndex);
2738 cls_medium_waste += msp->class_vsm()->sum_waste_in_chunks_in_use(MediumIndex);
2739 cls_medium_count += msp->class_vsm()->sum_count_in_chunks_in_use(MediumIndex);
2740 cls_humongous_count += msp->class_vsm()->sum_count_in_chunks_in_use(HumongousIndex);
2741 }
2742 }
2743 out->print_cr(" class: " SIZE_FORMAT " specialized(s) " SIZE_FORMAT ", "
2744 SIZE_FORMAT " small(s) " SIZE_FORMAT ", "
2745 SIZE_FORMAT " medium(s) " SIZE_FORMAT ", "
2746 "large count " SIZE_FORMAT,
2747 cls_specialized_count, cls_specialized_waste,
2748 cls_small_count, cls_small_waste,
2749 cls_medium_count, cls_medium_waste, cls_humongous_count);
2750 }
2751
2752 // Print total fragmentation for data and class metaspaces separately
2753 void MetaspaceAux::print_waste(outputStream* out) {
2754 size_t specialized_waste = 0, small_waste = 0, medium_waste = 0;
2755 size_t specialized_count = 0, small_count = 0, medium_count = 0, humongous_count = 0;
2756
2757 ClassLoaderDataGraphMetaspaceIterator iter;
2758 while (iter.repeat()) {
2759 Metaspace* msp = iter.get_next();
2760 if (msp != NULL) {
2761 specialized_waste += msp->vsm()->sum_waste_in_chunks_in_use(SpecializedIndex);
2762 specialized_count += msp->vsm()->sum_count_in_chunks_in_use(SpecializedIndex);
2763 small_waste += msp->vsm()->sum_waste_in_chunks_in_use(SmallIndex);
2764 small_count += msp->vsm()->sum_count_in_chunks_in_use(SmallIndex);
2765 medium_waste += msp->vsm()->sum_waste_in_chunks_in_use(MediumIndex);
2766 medium_count += msp->vsm()->sum_count_in_chunks_in_use(MediumIndex);
2767 humongous_count += msp->vsm()->sum_count_in_chunks_in_use(HumongousIndex);
2768 }
2769 }
2770 out->print_cr("Total fragmentation waste (words) doesn't count free space");
2771 out->print_cr(" data: " SIZE_FORMAT " specialized(s) " SIZE_FORMAT ", "
2772 SIZE_FORMAT " small(s) " SIZE_FORMAT ", "
2773 SIZE_FORMAT " medium(s) " SIZE_FORMAT ", "
2774 "large count " SIZE_FORMAT,
2775 specialized_count, specialized_waste, small_count,
2776 small_waste, medium_count, medium_waste, humongous_count);
2777 if (Metaspace::using_class_space()) {
2778 print_class_waste(out);
2779 }
2780 }
2781
2782 // Dump global metaspace things from the end of ClassLoaderDataGraph
2783 void MetaspaceAux::dump(outputStream* out) {
2784 out->print_cr("All Metaspace:");
2785 out->print("data space: "); print_on(out, Metaspace::NonClassType);
2786 out->print("class space: "); print_on(out, Metaspace::ClassType);
2787 print_waste(out);
2788 }
2789
2790 void MetaspaceAux::verify_free_chunks() {
2791 Metaspace::chunk_manager_metadata()->verify();
2792 if (Metaspace::using_class_space()) {
2793 Metaspace::chunk_manager_class()->verify();
2794 }
2795 }
2796
2797 void MetaspaceAux::verify_capacity() {
2798 #ifdef ASSERT
2799 size_t running_sum_capacity_bytes = capacity_bytes();
2800 // For purposes of the running sum of capacity, verify against capacity
2801 size_t capacity_in_use_bytes = capacity_bytes_slow();
2802 assert(running_sum_capacity_bytes == capacity_in_use_bytes,
2803 "capacity_words() * BytesPerWord " SIZE_FORMAT
2804 " capacity_bytes_slow()" SIZE_FORMAT,
2805 running_sum_capacity_bytes, capacity_in_use_bytes);
2806 for (Metaspace::MetadataType i = Metaspace::ClassType;
2807 i < Metaspace:: MetadataTypeCount;
2808 i = (Metaspace::MetadataType)(i + 1)) {
2809 size_t capacity_in_use_bytes = capacity_bytes_slow(i);
2810 assert(capacity_bytes(i) == capacity_in_use_bytes,
2811 "capacity_bytes(%u) " SIZE_FORMAT
2812 " capacity_bytes_slow(%u)" SIZE_FORMAT,
2813 i, capacity_bytes(i), i, capacity_in_use_bytes);
2814 }
2815 #endif
2816 }
2817
2818 void MetaspaceAux::verify_used() {
2819 #ifdef ASSERT
2820 size_t running_sum_used_bytes = used_bytes();
2821 // For purposes of the running sum of used, verify against used
2822 size_t used_in_use_bytes = used_bytes_slow();
2823 assert(used_bytes() == used_in_use_bytes,
2824 "used_bytes() " SIZE_FORMAT
2825 " used_bytes_slow()" SIZE_FORMAT,
2826 used_bytes(), used_in_use_bytes);
2827 for (Metaspace::MetadataType i = Metaspace::ClassType;
2828 i < Metaspace:: MetadataTypeCount;
2829 i = (Metaspace::MetadataType)(i + 1)) {
2830 size_t used_in_use_bytes = used_bytes_slow(i);
2831 assert(used_bytes(i) == used_in_use_bytes,
2832 "used_bytes(%u) " SIZE_FORMAT
2833 " used_bytes_slow(%u)" SIZE_FORMAT,
2834 i, used_bytes(i), i, used_in_use_bytes);
2835 }
2836 #endif
2837 }
2838
2839 void MetaspaceAux::verify_metrics() {
2840 verify_capacity();
2841 verify_used();
2842 }
2843
2844
2845 // Metaspace methods
2846
2847 size_t Metaspace::_first_chunk_word_size = 0;
2848 size_t Metaspace::_first_class_chunk_word_size = 0;
2849
2850 size_t Metaspace::_commit_alignment = 0;
2851 size_t Metaspace::_reserve_alignment = 0;
2852
2853 Metaspace::Metaspace(Mutex* lock, MetaspaceType type) {
2854 initialize(lock, type);
2855 }
2856
2857 Metaspace::~Metaspace() {
2858 delete _vsm;
2859 if (using_class_space()) {
2860 delete _class_vsm;
2861 }
2862 }
2863
2864 VirtualSpaceList* Metaspace::_space_list = NULL;
2865 VirtualSpaceList* Metaspace::_class_space_list = NULL;
2866
2867 ChunkManager* Metaspace::_chunk_manager_metadata = NULL;
2868 ChunkManager* Metaspace::_chunk_manager_class = NULL;
2869
2870 #define VIRTUALSPACEMULTIPLIER 2
2871
2872 #ifdef _LP64
2873 static const uint64_t UnscaledClassSpaceMax = (uint64_t(max_juint) + 1);
2874
2875 void Metaspace::set_narrow_klass_base_and_shift(address metaspace_base, address cds_base) {
2876 // Figure out the narrow_klass_base and the narrow_klass_shift. The
2877 // narrow_klass_base is the lower of the metaspace base and the cds base
2878 // (if cds is enabled). The narrow_klass_shift depends on the distance
2879 // between the lower base and higher address.
2880 address lower_base;
2881 address higher_address;
2882 #if INCLUDE_CDS
2883 if (UseSharedSpaces) {
2884 higher_address = MAX2((address)(cds_base + FileMapInfo::shared_spaces_size()),
2885 (address)(metaspace_base + compressed_class_space_size()));
2886 lower_base = MIN2(metaspace_base, cds_base);
2887 } else
2888 #endif
2889 {
2890 higher_address = metaspace_base + compressed_class_space_size();
2891 lower_base = metaspace_base;
2892
2893 uint64_t klass_encoding_max = UnscaledClassSpaceMax << LogKlassAlignmentInBytes;
2894 // If compressed class space fits in lower 32G, we don't need a base.
2895 if (higher_address <= (address)klass_encoding_max) {
2896 lower_base = 0; // Effectively lower base is zero.
2897 }
2898 }
2899
2900 Universe::set_narrow_klass_base(lower_base);
2901
2902 if ((uint64_t)(higher_address - lower_base) <= UnscaledClassSpaceMax) {
2903 Universe::set_narrow_klass_shift(0);
2904 } else {
2905 assert(!UseSharedSpaces, "Cannot shift with UseSharedSpaces");
2906 Universe::set_narrow_klass_shift(LogKlassAlignmentInBytes);
2907 }
2908 }
2909
2910 #if INCLUDE_CDS
2911 // Return TRUE if the specified metaspace_base and cds_base are close enough
2912 // to work with compressed klass pointers.
2913 bool Metaspace::can_use_cds_with_metaspace_addr(char* metaspace_base, address cds_base) {
2914 assert(cds_base != 0 && UseSharedSpaces, "Only use with CDS");
2915 assert(UseCompressedClassPointers, "Only use with CompressedKlassPtrs");
2916 address lower_base = MIN2((address)metaspace_base, cds_base);
2917 address higher_address = MAX2((address)(cds_base + FileMapInfo::shared_spaces_size()),
2918 (address)(metaspace_base + compressed_class_space_size()));
2919 return ((uint64_t)(higher_address - lower_base) <= UnscaledClassSpaceMax);
2920 }
2921 #endif
2922
2923 // Try to allocate the metaspace at the requested addr.
2924 void Metaspace::allocate_metaspace_compressed_klass_ptrs(char* requested_addr, address cds_base) {
2925 assert(using_class_space(), "called improperly");
2926 assert(UseCompressedClassPointers, "Only use with CompressedKlassPtrs");
2927 assert(compressed_class_space_size() < KlassEncodingMetaspaceMax,
2928 "Metaspace size is too big");
2929 assert_is_ptr_aligned(requested_addr, _reserve_alignment);
2930 assert_is_ptr_aligned(cds_base, _reserve_alignment);
2931 assert_is_size_aligned(compressed_class_space_size(), _reserve_alignment);
2932
2933 // Don't use large pages for the class space.
2934 bool large_pages = false;
2935
2936 #if !(defined(AARCH64) || defined(AIX))
2937 ReservedSpace metaspace_rs = ReservedSpace(compressed_class_space_size(),
2938 _reserve_alignment,
2939 large_pages,
2940 requested_addr);
2941 #else // AARCH64
2942 ReservedSpace metaspace_rs;
2943
2944 // Our compressed klass pointers may fit nicely into the lower 32
2945 // bits.
2946 if ((uint64_t)requested_addr + compressed_class_space_size() < 4*G) {
2947 metaspace_rs = ReservedSpace(compressed_class_space_size(),
2948 _reserve_alignment,
2949 large_pages,
2950 requested_addr);
2951 }
2952
2953 if (! metaspace_rs.is_reserved()) {
2954 // Aarch64: Try to align metaspace so that we can decode a compressed
2955 // klass with a single MOVK instruction. We can do this iff the
2956 // compressed class base is a multiple of 4G.
2957 // Aix: Search for a place where we can find memory. If we need to load
2958 // the base, 4G alignment is helpful, too.
2959 size_t increment = AARCH64_ONLY(4*)G;
2960 for (char *a = (char*)align_ptr_up(requested_addr, increment);
2961 a < (char*)(1024*G);
2962 a += increment) {
2963 if (a == (char *)(32*G)) {
2964 // Go faster from here on. Zero-based is no longer possible.
2965 increment = 4*G;
2966 }
2967
2968 #if INCLUDE_CDS
2969 if (UseSharedSpaces
2970 && ! can_use_cds_with_metaspace_addr(a, cds_base)) {
2971 // We failed to find an aligned base that will reach. Fall
2972 // back to using our requested addr.
2973 metaspace_rs = ReservedSpace(compressed_class_space_size(),
2974 _reserve_alignment,
2975 large_pages,
2976 requested_addr);
2977 break;
2978 }
2979 #endif
2980
2981 metaspace_rs = ReservedSpace(compressed_class_space_size(),
2982 _reserve_alignment,
2983 large_pages,
2984 a);
2985 if (metaspace_rs.is_reserved())
2986 break;
2987 }
2988 }
2989
2990 #endif // AARCH64
2991
2992 if (!metaspace_rs.is_reserved()) {
2993 #if INCLUDE_CDS
2994 if (UseSharedSpaces) {
2995 size_t increment = align_size_up(1*G, _reserve_alignment);
2996
2997 // Keep trying to allocate the metaspace, increasing the requested_addr
2998 // by 1GB each time, until we reach an address that will no longer allow
2999 // use of CDS with compressed klass pointers.
3000 char *addr = requested_addr;
3001 while (!metaspace_rs.is_reserved() && (addr + increment > addr) &&
3002 can_use_cds_with_metaspace_addr(addr + increment, cds_base)) {
3003 addr = addr + increment;
3004 metaspace_rs = ReservedSpace(compressed_class_space_size(),
3005 _reserve_alignment, large_pages, addr);
3006 }
3007 }
3008 #endif
3009 // If no successful allocation then try to allocate the space anywhere. If
3010 // that fails then OOM doom. At this point we cannot try allocating the
3011 // metaspace as if UseCompressedClassPointers is off because too much
3012 // initialization has happened that depends on UseCompressedClassPointers.
3013 // So, UseCompressedClassPointers cannot be turned off at this point.
3014 if (!metaspace_rs.is_reserved()) {
3015 metaspace_rs = ReservedSpace(compressed_class_space_size(),
3016 _reserve_alignment, large_pages);
3017 if (!metaspace_rs.is_reserved()) {
3018 vm_exit_during_initialization(err_msg("Could not allocate metaspace: " SIZE_FORMAT " bytes",
3019 compressed_class_space_size()));
3020 }
3021 }
3022 }
3023
3024 // If we got here then the metaspace got allocated.
3025 MemTracker::record_virtual_memory_type((address)metaspace_rs.base(), mtClass);
3026
3027 #if INCLUDE_CDS
3028 // Verify that we can use shared spaces. Otherwise, turn off CDS.
3029 if (UseSharedSpaces && !can_use_cds_with_metaspace_addr(metaspace_rs.base(), cds_base)) {
3030 FileMapInfo::stop_sharing_and_unmap(
3031 "Could not allocate metaspace at a compatible address");
3032 }
3033 #endif
3034 set_narrow_klass_base_and_shift((address)metaspace_rs.base(),
3035 UseSharedSpaces ? (address)cds_base : 0);
3036
3037 initialize_class_space(metaspace_rs);
3038
3039 if (log_is_enabled(Trace, gc, metaspace)) {
3040 Log(gc, metaspace) log;
3041 ResourceMark rm;
3042 print_compressed_class_space(log.trace_stream(), requested_addr);
3043 }
3044 }
3045
3046 void Metaspace::print_compressed_class_space(outputStream* st, const char* requested_addr) {
3047 st->print_cr("Narrow klass base: " PTR_FORMAT ", Narrow klass shift: %d",
3048 p2i(Universe::narrow_klass_base()), Universe::narrow_klass_shift());
3049 if (_class_space_list != NULL) {
3050 address base = (address)_class_space_list->current_virtual_space()->bottom();
3051 st->print("Compressed class space size: " SIZE_FORMAT " Address: " PTR_FORMAT,
3052 compressed_class_space_size(), p2i(base));
3053 if (requested_addr != 0) {
3054 st->print(" Req Addr: " PTR_FORMAT, p2i(requested_addr));
3055 }
3056 st->cr();
3057 }
3058 }
3059
3060 // For UseCompressedClassPointers the class space is reserved above the top of
3061 // the Java heap. The argument passed in is at the base of the compressed space.
3062 void Metaspace::initialize_class_space(ReservedSpace rs) {
3063 // The reserved space size may be bigger because of alignment, esp with UseLargePages
3064 assert(rs.size() >= CompressedClassSpaceSize,
3065 SIZE_FORMAT " != " SIZE_FORMAT, rs.size(), CompressedClassSpaceSize);
3066 assert(using_class_space(), "Must be using class space");
3067 _class_space_list = new VirtualSpaceList(rs);
3068 _chunk_manager_class = new ChunkManager(SpecializedChunk, ClassSmallChunk, ClassMediumChunk);
3069
3070 if (!_class_space_list->initialization_succeeded()) {
3071 vm_exit_during_initialization("Failed to setup compressed class space virtual space list.");
3072 }
3073 }
3074
3075 #endif
3076
3077 void Metaspace::ergo_initialize() {
3078 if (DumpSharedSpaces) {
3079 // Using large pages when dumping the shared archive is currently not implemented.
3080 FLAG_SET_ERGO(bool, UseLargePagesInMetaspace, false);
3081 }
3082
3083 size_t page_size = os::vm_page_size();
3084 if (UseLargePages && UseLargePagesInMetaspace) {
3085 page_size = os::large_page_size();
3086 }
3087
3088 _commit_alignment = page_size;
3089 _reserve_alignment = MAX2(page_size, (size_t)os::vm_allocation_granularity());
3090
3091 // Do not use FLAG_SET_ERGO to update MaxMetaspaceSize, since this will
3092 // override if MaxMetaspaceSize was set on the command line or not.
3093 // This information is needed later to conform to the specification of the
3094 // java.lang.management.MemoryUsage API.
3095 //
3096 // Ideally, we would be able to set the default value of MaxMetaspaceSize in
3097 // globals.hpp to the aligned value, but this is not possible, since the
3098 // alignment depends on other flags being parsed.
3099 MaxMetaspaceSize = align_size_down_bounded(MaxMetaspaceSize, _reserve_alignment);
3100
3101 if (MetaspaceSize > MaxMetaspaceSize) {
3102 MetaspaceSize = MaxMetaspaceSize;
3103 }
3104
3105 MetaspaceSize = align_size_down_bounded(MetaspaceSize, _commit_alignment);
3106
3107 assert(MetaspaceSize <= MaxMetaspaceSize, "MetaspaceSize should be limited by MaxMetaspaceSize");
3108
3109 MinMetaspaceExpansion = align_size_down_bounded(MinMetaspaceExpansion, _commit_alignment);
3110 MaxMetaspaceExpansion = align_size_down_bounded(MaxMetaspaceExpansion, _commit_alignment);
3111
3112 CompressedClassSpaceSize = align_size_down_bounded(CompressedClassSpaceSize, _reserve_alignment);
3113 set_compressed_class_space_size(CompressedClassSpaceSize);
3114 }
3115
3116 void Metaspace::global_initialize() {
3117 MetaspaceGC::initialize();
3118
3119 // Initialize the alignment for shared spaces.
3120 int max_alignment = os::vm_allocation_granularity();
3121 size_t cds_total = 0;
3122
3123 MetaspaceShared::set_max_alignment(max_alignment);
3124
3125 if (DumpSharedSpaces) {
3126 #if INCLUDE_CDS
3127 MetaspaceShared::estimate_regions_size();
3128
3129 SharedReadOnlySize = align_size_up(SharedReadOnlySize, max_alignment);
3130 SharedReadWriteSize = align_size_up(SharedReadWriteSize, max_alignment);
3131 SharedMiscDataSize = align_size_up(SharedMiscDataSize, max_alignment);
3132 SharedMiscCodeSize = align_size_up(SharedMiscCodeSize, max_alignment);
3133
3134 // Initialize with the sum of the shared space sizes. The read-only
3135 // and read write metaspace chunks will be allocated out of this and the
3136 // remainder is the misc code and data chunks.
3137 cds_total = FileMapInfo::shared_spaces_size();
3138 cds_total = align_size_up(cds_total, _reserve_alignment);
3139 _space_list = new VirtualSpaceList(cds_total/wordSize);
3140 _chunk_manager_metadata = new ChunkManager(SpecializedChunk, SmallChunk, MediumChunk);
3141
3142 if (!_space_list->initialization_succeeded()) {
3143 vm_exit_during_initialization("Unable to dump shared archive.", NULL);
3144 }
3145
3146 #ifdef _LP64
3147 if (cds_total + compressed_class_space_size() > UnscaledClassSpaceMax) {
3148 vm_exit_during_initialization("Unable to dump shared archive.",
3149 err_msg("Size of archive (" SIZE_FORMAT ") + compressed class space ("
3150 SIZE_FORMAT ") == total (" SIZE_FORMAT ") is larger than compressed "
3151 "klass limit: " UINT64_FORMAT, cds_total, compressed_class_space_size(),
3152 cds_total + compressed_class_space_size(), UnscaledClassSpaceMax));
3153 }
3154
3155 // Set the compressed klass pointer base so that decoding of these pointers works
3156 // properly when creating the shared archive.
3157 assert(UseCompressedOops && UseCompressedClassPointers,
3158 "UseCompressedOops and UseCompressedClassPointers must be set");
3159 Universe::set_narrow_klass_base((address)_space_list->current_virtual_space()->bottom());
3160 log_develop_trace(gc, metaspace)("Setting_narrow_klass_base to Address: " PTR_FORMAT,
3161 p2i(_space_list->current_virtual_space()->bottom()));
3162
3163 Universe::set_narrow_klass_shift(0);
3164 #endif // _LP64
3165 #endif // INCLUDE_CDS
3166 } else {
3167 #if INCLUDE_CDS
3168 if (UseSharedSpaces) {
3169 // If using shared space, open the file that contains the shared space
3170 // and map in the memory before initializing the rest of metaspace (so
3171 // the addresses don't conflict)
3172 address cds_address = NULL;
3173 FileMapInfo* mapinfo = new FileMapInfo();
3174
3175 // Open the shared archive file, read and validate the header. If
3176 // initialization fails, shared spaces [UseSharedSpaces] are
3177 // disabled and the file is closed.
3178 // Map in spaces now also
3179 if (mapinfo->initialize() && MetaspaceShared::map_shared_spaces(mapinfo)) {
3180 cds_total = FileMapInfo::shared_spaces_size();
3181 cds_address = (address)mapinfo->header()->region_addr(0);
3182 #ifdef _LP64
3183 if (using_class_space()) {
3184 char* cds_end = (char*)(cds_address + cds_total);
3185 cds_end = (char *)align_ptr_up(cds_end, _reserve_alignment);
3186 // If UseCompressedClassPointers is set then allocate the metaspace area
3187 // above the heap and above the CDS area (if it exists).
3188 allocate_metaspace_compressed_klass_ptrs(cds_end, cds_address);
3189 // Map the shared string space after compressed pointers
3190 // because it relies on compressed class pointers setting to work
3191 mapinfo->map_string_regions();
3192 }
3193 #endif // _LP64
3194 } else {
3195 assert(!mapinfo->is_open() && !UseSharedSpaces,
3196 "archive file not closed or shared spaces not disabled.");
3197 }
3198 }
3199 #endif // INCLUDE_CDS
3200
3201 #ifdef _LP64
3202 if (!UseSharedSpaces && using_class_space()) {
3203 char* base = (char*)align_ptr_up(Universe::heap()->reserved_region().end(), _reserve_alignment);
3204 allocate_metaspace_compressed_klass_ptrs(base, 0);
3205 }
3206 #endif // _LP64
3207
3208 // Initialize these before initializing the VirtualSpaceList
3209 _first_chunk_word_size = InitialBootClassLoaderMetaspaceSize / BytesPerWord;
3210 _first_chunk_word_size = align_word_size_up(_first_chunk_word_size);
3211 // Make the first class chunk bigger than a medium chunk so it's not put
3212 // on the medium chunk list. The next chunk will be small and progress
3213 // from there. This size calculated by -version.
3214 _first_class_chunk_word_size = MIN2((size_t)MediumChunk*6,
3215 (CompressedClassSpaceSize/BytesPerWord)*2);
3216 _first_class_chunk_word_size = align_word_size_up(_first_class_chunk_word_size);
3217 // Arbitrarily set the initial virtual space to a multiple
3218 // of the boot class loader size.
3219 size_t word_size = VIRTUALSPACEMULTIPLIER * _first_chunk_word_size;
3220 word_size = align_size_up(word_size, Metaspace::reserve_alignment_words());
3221
3222 // Initialize the list of virtual spaces.
3223 _space_list = new VirtualSpaceList(word_size);
3224 _chunk_manager_metadata = new ChunkManager(SpecializedChunk, SmallChunk, MediumChunk);
3225
3226 if (!_space_list->initialization_succeeded()) {
3227 vm_exit_during_initialization("Unable to setup metadata virtual space list.", NULL);
3228 }
3229 }
3230
3231 _tracer = new MetaspaceTracer();
3232 }
3233
3234 void Metaspace::post_initialize() {
3235 MetaspaceGC::post_initialize();
3236 }
3237
3238 Metachunk* Metaspace::get_initialization_chunk(MetadataType mdtype,
3239 size_t chunk_word_size,
3240 size_t chunk_bunch) {
3241 // Get a chunk from the chunk freelist
3242 Metachunk* chunk = get_chunk_manager(mdtype)->chunk_freelist_allocate(chunk_word_size);
3243 if (chunk != NULL) {
3244 return chunk;
3245 }
3246
3247 return get_space_list(mdtype)->get_new_chunk(chunk_word_size, chunk_word_size, chunk_bunch);
3248 }
3249
3250 void Metaspace::initialize(Mutex* lock, MetaspaceType type) {
3251
3252 assert(space_list() != NULL,
3253 "Metadata VirtualSpaceList has not been initialized");
3254 assert(chunk_manager_metadata() != NULL,
3255 "Metadata ChunkManager has not been initialized");
3256
3257 _vsm = new SpaceManager(NonClassType, lock);
3258 if (_vsm == NULL) {
3259 return;
3260 }
3261 size_t word_size;
3262 size_t class_word_size;
3263 vsm()->get_initial_chunk_sizes(type, &word_size, &class_word_size);
3264
3265 if (using_class_space()) {
3266 assert(class_space_list() != NULL,
3267 "Class VirtualSpaceList has not been initialized");
3268 assert(chunk_manager_class() != NULL,
3269 "Class ChunkManager has not been initialized");
3270
3271 // Allocate SpaceManager for classes.
3272 _class_vsm = new SpaceManager(ClassType, lock);
3273 if (_class_vsm == NULL) {
3274 return;
3275 }
3276 }
3277
3278 MutexLockerEx cl(SpaceManager::expand_lock(), Mutex::_no_safepoint_check_flag);
3279
3280 // Allocate chunk for metadata objects
3281 Metachunk* new_chunk = get_initialization_chunk(NonClassType,
3282 word_size,
3283 vsm()->medium_chunk_bunch());
3284 // For dumping shared archive, report error if allocation has failed.
3285 if (DumpSharedSpaces && new_chunk == NULL) {
3286 report_insufficient_metaspace(MetaspaceAux::committed_bytes() + word_size * BytesPerWord);
3287 }
3288 assert(!DumpSharedSpaces || new_chunk != NULL, "should have enough space for both chunks");
3289 if (new_chunk != NULL) {
3290 // Add to this manager's list of chunks in use and current_chunk().
3291 vsm()->add_chunk(new_chunk, true);
3292 }
3293
3294 // Allocate chunk for class metadata objects
3295 if (using_class_space()) {
3296 Metachunk* class_chunk = get_initialization_chunk(ClassType,
3297 class_word_size,
3298 class_vsm()->medium_chunk_bunch());
3299 if (class_chunk != NULL) {
3300 class_vsm()->add_chunk(class_chunk, true);
3301 } else {
3302 // For dumping shared archive, report error if allocation has failed.
3303 if (DumpSharedSpaces) {
3304 report_insufficient_metaspace(MetaspaceAux::committed_bytes() + class_word_size * BytesPerWord);
3305 }
3306 }
3307 }
3308
3309 _alloc_record_head = NULL;
3310 _alloc_record_tail = NULL;
3311 }
3312
3313 size_t Metaspace::align_word_size_up(size_t word_size) {
3314 size_t byte_size = word_size * wordSize;
3315 return ReservedSpace::allocation_align_size_up(byte_size) / wordSize;
3316 }
3317
3318 MetaWord* Metaspace::allocate(size_t word_size, MetadataType mdtype) {
3319 // DumpSharedSpaces doesn't use class metadata area (yet)
3320 // Also, don't use class_vsm() unless UseCompressedClassPointers is true.
3321 if (is_class_space_allocation(mdtype)) {
3322 return class_vsm()->allocate(word_size);
3323 } else {
3324 return vsm()->allocate(word_size);
3325 }
3326 }
3327
3328 MetaWord* Metaspace::expand_and_allocate(size_t word_size, MetadataType mdtype) {
3329 size_t delta_bytes = MetaspaceGC::delta_capacity_until_GC(word_size * BytesPerWord);
3330 assert(delta_bytes > 0, "Must be");
3331
3332 size_t before = 0;
3333 size_t after = 0;
3334 MetaWord* res;
3335 bool incremented;
3336
3337 // Each thread increments the HWM at most once. Even if the thread fails to increment
3338 // the HWM, an allocation is still attempted. This is because another thread must then
3339 // have incremented the HWM and therefore the allocation might still succeed.
3340 do {
3341 incremented = MetaspaceGC::inc_capacity_until_GC(delta_bytes, &after, &before);
3342 res = allocate(word_size, mdtype);
3343 } while (!incremented && res == NULL);
3344
3345 if (incremented) {
3346 tracer()->report_gc_threshold(before, after,
3347 MetaspaceGCThresholdUpdater::ExpandAndAllocate);
3348 log_trace(gc, metaspace)("Increase capacity to GC from " SIZE_FORMAT " to " SIZE_FORMAT, before, after);
3349 }
3350
3351 return res;
3352 }
3353
3354 // Space allocated in the Metaspace. This may
3355 // be across several metadata virtual spaces.
3356 char* Metaspace::bottom() const {
3357 assert(DumpSharedSpaces, "only useful and valid for dumping shared spaces");
3358 return (char*)vsm()->current_chunk()->bottom();
3359 }
3360
3361 size_t Metaspace::used_words_slow(MetadataType mdtype) const {
3362 if (mdtype == ClassType) {
3363 return using_class_space() ? class_vsm()->sum_used_in_chunks_in_use() : 0;
3364 } else {
3365 return vsm()->sum_used_in_chunks_in_use(); // includes overhead!
3366 }
3367 }
3368
3369 size_t Metaspace::free_words_slow(MetadataType mdtype) const {
3370 if (mdtype == ClassType) {
3371 return using_class_space() ? class_vsm()->sum_free_in_chunks_in_use() : 0;
3372 } else {
3373 return vsm()->sum_free_in_chunks_in_use();
3374 }
3375 }
3376
3377 // Space capacity in the Metaspace. It includes
3378 // space in the list of chunks from which allocations
3379 // have been made. Don't include space in the global freelist and
3380 // in the space available in the dictionary which
3381 // is already counted in some chunk.
3382 size_t Metaspace::capacity_words_slow(MetadataType mdtype) const {
3383 if (mdtype == ClassType) {
3384 return using_class_space() ? class_vsm()->sum_capacity_in_chunks_in_use() : 0;
3385 } else {
3386 return vsm()->sum_capacity_in_chunks_in_use();
3387 }
3388 }
3389
3390 size_t Metaspace::used_bytes_slow(MetadataType mdtype) const {
3391 return used_words_slow(mdtype) * BytesPerWord;
3392 }
3393
3394 size_t Metaspace::capacity_bytes_slow(MetadataType mdtype) const {
3395 return capacity_words_slow(mdtype) * BytesPerWord;
3396 }
3397
3398 size_t Metaspace::allocated_blocks_bytes() const {
3399 return vsm()->allocated_blocks_bytes() +
3400 (using_class_space() ? class_vsm()->allocated_blocks_bytes() : 0);
3401 }
3402
3403 size_t Metaspace::allocated_chunks_bytes() const {
3404 return vsm()->allocated_chunks_bytes() +
3405 (using_class_space() ? class_vsm()->allocated_chunks_bytes() : 0);
3406 }
3407
3408 void Metaspace::deallocate(MetaWord* ptr, size_t word_size, bool is_class) {
3409 assert(!SafepointSynchronize::is_at_safepoint()
3410 || Thread::current()->is_VM_thread(), "should be the VM thread");
3411
3412 if (DumpSharedSpaces && PrintSharedSpaces) {
3413 record_deallocation(ptr, vsm()->get_raw_word_size(word_size));
3414 }
3415
3416 MutexLockerEx ml(vsm()->lock(), Mutex::_no_safepoint_check_flag);
3417
3418 if (word_size < TreeChunk<Metablock, FreeList<Metablock> >::min_size()) {
3419 // Dark matter. Too small for dictionary.
3420 #ifdef ASSERT
3421 Copy::fill_to_words((HeapWord*)ptr, word_size, 0xf5f5f5f5);
3422 #endif
3423 return;
3424 }
3425 if (is_class && using_class_space()) {
3426 class_vsm()->deallocate(ptr, word_size);
3427 } else {
3428 vsm()->deallocate(ptr, word_size);
3429 }
3430 }
3431
3432
3433 MetaWord* Metaspace::allocate(ClassLoaderData* loader_data, size_t word_size,
3434 bool read_only, MetaspaceObj::Type type, TRAPS) {
3435 if (HAS_PENDING_EXCEPTION) {
3436 assert(false, "Should not allocate with exception pending");
3437 return NULL; // caller does a CHECK_NULL too
3438 }
3439
3440 assert(loader_data != NULL, "Should never pass around a NULL loader_data. "
3441 "ClassLoaderData::the_null_class_loader_data() should have been used.");
3442
3443 // Allocate in metaspaces without taking out a lock, because it deadlocks
3444 // with the SymbolTable_lock. Dumping is single threaded for now. We'll have
3445 // to revisit this for application class data sharing.
3446 if (DumpSharedSpaces) {
3447 assert(type > MetaspaceObj::UnknownType && type < MetaspaceObj::_number_of_types, "sanity");
3448 Metaspace* space = read_only ? loader_data->ro_metaspace() : loader_data->rw_metaspace();
3449 MetaWord* result = space->allocate(word_size, NonClassType);
3450 if (result == NULL) {
3451 report_out_of_shared_space(read_only ? SharedReadOnly : SharedReadWrite);
3452 }
3453 if (PrintSharedSpaces) {
3454 space->record_allocation(result, type, space->vsm()->get_raw_word_size(word_size));
3455 }
3456
3457 // Zero initialize.
3458 Copy::fill_to_words((HeapWord*)result, word_size, 0);
3459
3460 return result;
3461 }
3462
3463 MetadataType mdtype = (type == MetaspaceObj::ClassType) ? ClassType : NonClassType;
3464
3465 // Try to allocate metadata.
3466 MetaWord* result = loader_data->metaspace_non_null()->allocate(word_size, mdtype);
3467
3468 if (result == NULL) {
3469 tracer()->report_metaspace_allocation_failure(loader_data, word_size, type, mdtype);
3470
3471 // Allocation failed.
3472 if (is_init_completed()) {
3473 // Only start a GC if the bootstrapping has completed.
3474
3475 // Try to clean out some memory and retry.
3476 result = Universe::heap()->collector_policy()->satisfy_failed_metadata_allocation(
3477 loader_data, word_size, mdtype);
3478 }
3479 }
3480
3481 if (result == NULL) {
3482 SpaceManager* sm;
3483 if (is_class_space_allocation(mdtype)) {
3484 sm = loader_data->metaspace_non_null()->class_vsm();
3485 } else {
3486 sm = loader_data->metaspace_non_null()->vsm();
3487 }
3488
3489 result = sm->get_small_chunk_and_allocate(word_size);
3490
3491 if (result == NULL) {
3492 report_metadata_oome(loader_data, word_size, type, mdtype, CHECK_NULL);
3493 }
3494 }
3495
3496 // Zero initialize.
3497 Copy::fill_to_words((HeapWord*)result, word_size, 0);
3498
3499 return result;
3500 }
3501
3502 size_t Metaspace::class_chunk_size(size_t word_size) {
3503 assert(using_class_space(), "Has to use class space");
3504 return class_vsm()->calc_chunk_size(word_size);
3505 }
3506
3507 void Metaspace::report_metadata_oome(ClassLoaderData* loader_data, size_t word_size, MetaspaceObj::Type type, MetadataType mdtype, TRAPS) {
3508 tracer()->report_metadata_oom(loader_data, word_size, type, mdtype);
3509
3510 // If result is still null, we are out of memory.
3511 Log(gc, metaspace, freelist) log;
3512 if (log.is_trace()) {
3513 log.trace("Metaspace allocation failed for size " SIZE_FORMAT, word_size);
3514 ResourceMark rm;
3515 outputStream* out = log.trace_stream();
3516 if (loader_data->metaspace_or_null() != NULL) {
3517 loader_data->dump(out);
3518 }
3519 MetaspaceAux::dump(out);
3520 }
3521
3522 bool out_of_compressed_class_space = false;
3523 if (is_class_space_allocation(mdtype)) {
3524 Metaspace* metaspace = loader_data->metaspace_non_null();
3525 out_of_compressed_class_space =
3526 MetaspaceAux::committed_bytes(Metaspace::ClassType) +
3527 (metaspace->class_chunk_size(word_size) * BytesPerWord) >
3528 CompressedClassSpaceSize;
3529 }
3530
3531 // -XX:+HeapDumpOnOutOfMemoryError and -XX:OnOutOfMemoryError support
3532 const char* space_string = out_of_compressed_class_space ?
3533 "Compressed class space" : "Metaspace";
3534
3535 report_java_out_of_memory(space_string);
3536
3537 if (JvmtiExport::should_post_resource_exhausted()) {
3538 JvmtiExport::post_resource_exhausted(
3539 JVMTI_RESOURCE_EXHAUSTED_OOM_ERROR,
3540 space_string);
3541 }
3542
3543 if (!is_init_completed()) {
3544 vm_exit_during_initialization("OutOfMemoryError", space_string);
3545 }
3546
3547 if (out_of_compressed_class_space) {
3548 THROW_OOP(Universe::out_of_memory_error_class_metaspace());
3549 } else {
3550 THROW_OOP(Universe::out_of_memory_error_metaspace());
3551 }
3552 }
3553
3554 const char* Metaspace::metadata_type_name(Metaspace::MetadataType mdtype) {
3555 switch (mdtype) {
3556 case Metaspace::ClassType: return "Class";
3557 case Metaspace::NonClassType: return "Metadata";
3558 default:
3559 assert(false, "Got bad mdtype: %d", (int) mdtype);
3560 return NULL;
3561 }
3562 }
3563
3564 void Metaspace::record_allocation(void* ptr, MetaspaceObj::Type type, size_t word_size) {
3565 assert(DumpSharedSpaces, "sanity");
3566
3567 int byte_size = (int)word_size * wordSize;
3568 AllocRecord *rec = new AllocRecord((address)ptr, type, byte_size);
3569
3570 if (_alloc_record_head == NULL) {
3571 _alloc_record_head = _alloc_record_tail = rec;
3572 } else if (_alloc_record_tail->_ptr + _alloc_record_tail->_byte_size == (address)ptr) {
3573 _alloc_record_tail->_next = rec;
3574 _alloc_record_tail = rec;
3575 } else {
3576 // slow linear search, but this doesn't happen that often, and only when dumping
3577 for (AllocRecord *old = _alloc_record_head; old; old = old->_next) {
3578 if (old->_ptr == ptr) {
3579 assert(old->_type == MetaspaceObj::DeallocatedType, "sanity");
3580 int remain_bytes = old->_byte_size - byte_size;
3581 assert(remain_bytes >= 0, "sanity");
3582 old->_type = type;
3583
3584 if (remain_bytes == 0) {
3585 delete(rec);
3586 } else {
3587 address remain_ptr = address(ptr) + byte_size;
3588 rec->_ptr = remain_ptr;
3589 rec->_byte_size = remain_bytes;
3590 rec->_type = MetaspaceObj::DeallocatedType;
3591 rec->_next = old->_next;
3592 old->_byte_size = byte_size;
3593 old->_next = rec;
3594 }
3595 return;
3596 }
3597 }
3598 assert(0, "reallocating a freed pointer that was not recorded");
3599 }
3600 }
3601
3602 void Metaspace::record_deallocation(void* ptr, size_t word_size) {
3603 assert(DumpSharedSpaces, "sanity");
3604
3605 for (AllocRecord *rec = _alloc_record_head; rec; rec = rec->_next) {
3606 if (rec->_ptr == ptr) {
3607 assert(rec->_byte_size == (int)word_size * wordSize, "sanity");
3608 rec->_type = MetaspaceObj::DeallocatedType;
3609 return;
3610 }
3611 }
3612
3613 assert(0, "deallocating a pointer that was not recorded");
3614 }
3615
3616 void Metaspace::iterate(Metaspace::AllocRecordClosure *closure) {
3617 assert(DumpSharedSpaces, "unimplemented for !DumpSharedSpaces");
3618
3619 address last_addr = (address)bottom();
3620
3621 for (AllocRecord *rec = _alloc_record_head; rec; rec = rec->_next) {
3622 address ptr = rec->_ptr;
3623 if (last_addr < ptr) {
3624 closure->doit(last_addr, MetaspaceObj::UnknownType, ptr - last_addr);
3625 }
3626 closure->doit(ptr, rec->_type, rec->_byte_size);
3627 last_addr = ptr + rec->_byte_size;
3628 }
3629
3630 address top = ((address)bottom()) + used_bytes_slow(Metaspace::NonClassType);
3631 if (last_addr < top) {
3632 closure->doit(last_addr, MetaspaceObj::UnknownType, top - last_addr);
3633 }
3634 }
3635
3636 void Metaspace::purge(MetadataType mdtype) {
3637 get_space_list(mdtype)->purge(get_chunk_manager(mdtype));
3638 }
3639
3640 void Metaspace::purge() {
3641 MutexLockerEx cl(SpaceManager::expand_lock(),
3642 Mutex::_no_safepoint_check_flag);
3643 purge(NonClassType);
3644 if (using_class_space()) {
3645 purge(ClassType);
3646 }
3647 }
3648
3649 void Metaspace::print_on(outputStream* out) const {
3650 // Print both class virtual space counts and metaspace.
3651 if (Verbose) {
3652 vsm()->print_on(out);
3653 if (using_class_space()) {
3654 class_vsm()->print_on(out);
3655 }
3656 }
3657 }
3658
3659 bool Metaspace::contains(const void* ptr) {
3660 if (UseSharedSpaces && MetaspaceShared::is_in_shared_space(ptr)) {
3661 return true;
3662 }
3663
3664 if (using_class_space() && get_space_list(ClassType)->contains(ptr)) {
3665 return true;
3666 }
3667
3668 return get_space_list(NonClassType)->contains(ptr);
3669 }
3670
3671 void Metaspace::verify() {
3672 vsm()->verify();
3673 if (using_class_space()) {
3674 class_vsm()->verify();
3675 }
3676 }
3677
3678 void Metaspace::dump(outputStream* const out) const {
3679 out->print_cr("\nVirtual space manager: " INTPTR_FORMAT, p2i(vsm()));
3680 vsm()->dump(out);
3681 if (using_class_space()) {
3682 out->print_cr("\nClass space manager: " INTPTR_FORMAT, p2i(class_vsm()));
3683 class_vsm()->dump(out);
3684 }
3685 }
3686
3687 /////////////// Unit tests ///////////////
3688
3689 #ifndef PRODUCT
3690
3691 class TestMetaspaceAuxTest : AllStatic {
3692 public:
3693 static void test_reserved() {
3694 size_t reserved = MetaspaceAux::reserved_bytes();
3695
3696 assert(reserved > 0, "assert");
3697
3698 size_t committed = MetaspaceAux::committed_bytes();
3699 assert(committed <= reserved, "assert");
3700
3701 size_t reserved_metadata = MetaspaceAux::reserved_bytes(Metaspace::NonClassType);
3702 assert(reserved_metadata > 0, "assert");
3703 assert(reserved_metadata <= reserved, "assert");
3704
3705 if (UseCompressedClassPointers) {
3706 size_t reserved_class = MetaspaceAux::reserved_bytes(Metaspace::ClassType);
3707 assert(reserved_class > 0, "assert");
3708 assert(reserved_class < reserved, "assert");
3709 }
3710 }
3711
3712 static void test_committed() {
3713 size_t committed = MetaspaceAux::committed_bytes();
3714
3715 assert(committed > 0, "assert");
3716
3717 size_t reserved = MetaspaceAux::reserved_bytes();
3718 assert(committed <= reserved, "assert");
3719
3720 size_t committed_metadata = MetaspaceAux::committed_bytes(Metaspace::NonClassType);
3721 assert(committed_metadata > 0, "assert");
3722 assert(committed_metadata <= committed, "assert");
3723
3724 if (UseCompressedClassPointers) {
3725 size_t committed_class = MetaspaceAux::committed_bytes(Metaspace::ClassType);
3726 assert(committed_class > 0, "assert");
3727 assert(committed_class < committed, "assert");
3728 }
3729 }
3730
3731 static void test_virtual_space_list_large_chunk() {
3732 VirtualSpaceList* vs_list = new VirtualSpaceList(os::vm_allocation_granularity());
3733 MutexLockerEx cl(SpaceManager::expand_lock(), Mutex::_no_safepoint_check_flag);
3734 // A size larger than VirtualSpaceSize (256k) and add one page to make it _not_ be
3735 // vm_allocation_granularity aligned on Windows.
3736 size_t large_size = (size_t)(2*256*K + (os::vm_page_size()/BytesPerWord));
3737 large_size += (os::vm_page_size()/BytesPerWord);
3738 vs_list->get_new_chunk(large_size, large_size, 0);
3739 }
3740
3741 static void test() {
3742 test_reserved();
3743 test_committed();
3744 test_virtual_space_list_large_chunk();
3745 }
3746 };
3747
3748 void TestMetaspaceAux_test() {
3749 TestMetaspaceAuxTest::test();
3750 }
3751
3752 class TestVirtualSpaceNodeTest {
3753 static void chunk_up(size_t words_left, size_t& num_medium_chunks,
3754 size_t& num_small_chunks,
3755 size_t& num_specialized_chunks) {
3756 num_medium_chunks = words_left / MediumChunk;
3757 words_left = words_left % MediumChunk;
3758
3759 num_small_chunks = words_left / SmallChunk;
3760 words_left = words_left % SmallChunk;
3761 // how many specialized chunks can we get?
3762 num_specialized_chunks = words_left / SpecializedChunk;
3763 assert(words_left % SpecializedChunk == 0, "should be nothing left");
3764 }
3765
3766 public:
3767 static void test() {
3768 MutexLockerEx ml(SpaceManager::expand_lock(), Mutex::_no_safepoint_check_flag);
3769 const size_t vsn_test_size_words = MediumChunk * 4;
3770 const size_t vsn_test_size_bytes = vsn_test_size_words * BytesPerWord;
3771
3772 // The chunk sizes must be multiples of eachother, or this will fail
3773 STATIC_ASSERT(MediumChunk % SmallChunk == 0);
3774 STATIC_ASSERT(SmallChunk % SpecializedChunk == 0);
3775
3776 { // No committed memory in VSN
3777 ChunkManager cm(SpecializedChunk, SmallChunk, MediumChunk);
3778 VirtualSpaceNode vsn(vsn_test_size_bytes);
3779 vsn.initialize();
3780 vsn.retire(&cm);
3781 assert(cm.sum_free_chunks_count() == 0, "did not commit any memory in the VSN");
3782 }
3783
3784 { // All of VSN is committed, half is used by chunks
3785 ChunkManager cm(SpecializedChunk, SmallChunk, MediumChunk);
3786 VirtualSpaceNode vsn(vsn_test_size_bytes);
3787 vsn.initialize();
3788 vsn.expand_by(vsn_test_size_words, vsn_test_size_words);
3789 vsn.get_chunk_vs(MediumChunk);
3790 vsn.get_chunk_vs(MediumChunk);
3791 vsn.retire(&cm);
3792 assert(cm.sum_free_chunks_count() == 2, "should have been memory left for 2 medium chunks");
3793 assert(cm.sum_free_chunks() == 2*MediumChunk, "sizes should add up");
3794 }
3795
3796 const size_t page_chunks = 4 * (size_t)os::vm_page_size() / BytesPerWord;
3797 // This doesn't work for systems with vm_page_size >= 16K.
3798 if (page_chunks < MediumChunk) {
3799 // 4 pages of VSN is committed, some is used by chunks
3800 ChunkManager cm(SpecializedChunk, SmallChunk, MediumChunk);
3801 VirtualSpaceNode vsn(vsn_test_size_bytes);
3802
3803 vsn.initialize();
3804 vsn.expand_by(page_chunks, page_chunks);
3805 vsn.get_chunk_vs(SmallChunk);
3806 vsn.get_chunk_vs(SpecializedChunk);
3807 vsn.retire(&cm);
3808
3809 // committed - used = words left to retire
3810 const size_t words_left = page_chunks - SmallChunk - SpecializedChunk;
3811
3812 size_t num_medium_chunks, num_small_chunks, num_spec_chunks;
3813 chunk_up(words_left, num_medium_chunks, num_small_chunks, num_spec_chunks);
3814
3815 assert(num_medium_chunks == 0, "should not get any medium chunks");
3816 assert(cm.sum_free_chunks_count() == (num_small_chunks + num_spec_chunks), "should be space for 3 chunks");
3817 assert(cm.sum_free_chunks() == words_left, "sizes should add up");
3818 }
3819
3820 { // Half of VSN is committed, a humongous chunk is used
3821 ChunkManager cm(SpecializedChunk, SmallChunk, MediumChunk);
3822 VirtualSpaceNode vsn(vsn_test_size_bytes);
3823 vsn.initialize();
3824 vsn.expand_by(MediumChunk * 2, MediumChunk * 2);
3825 vsn.get_chunk_vs(MediumChunk + SpecializedChunk); // Humongous chunks will be aligned up to MediumChunk + SpecializedChunk
3826 vsn.retire(&cm);
3827
3828 const size_t words_left = MediumChunk * 2 - (MediumChunk + SpecializedChunk);
3829 size_t num_medium_chunks, num_small_chunks, num_spec_chunks;
3830 chunk_up(words_left, num_medium_chunks, num_small_chunks, num_spec_chunks);
3831
3832 assert(num_medium_chunks == 0, "should not get any medium chunks");
3833 assert(cm.sum_free_chunks_count() == (num_small_chunks + num_spec_chunks), "should be space for 3 chunks");
3834 assert(cm.sum_free_chunks() == words_left, "sizes should add up");
3835 }
3836
3837 }
3838
3839 #define assert_is_available_positive(word_size) \
3840 assert(vsn.is_available(word_size), \
3841 #word_size ": " PTR_FORMAT " bytes were not available in " \
3842 "VirtualSpaceNode [" PTR_FORMAT ", " PTR_FORMAT ")", \
3843 (uintptr_t)(word_size * BytesPerWord), p2i(vsn.bottom()), p2i(vsn.end()));
3844
3845 #define assert_is_available_negative(word_size) \
3846 assert(!vsn.is_available(word_size), \
3847 #word_size ": " PTR_FORMAT " bytes should not be available in " \
3848 "VirtualSpaceNode [" PTR_FORMAT ", " PTR_FORMAT ")", \
3849 (uintptr_t)(word_size * BytesPerWord), p2i(vsn.bottom()), p2i(vsn.end()));
3850
3851 static void test_is_available_positive() {
3852 // Reserve some memory.
3853 VirtualSpaceNode vsn(os::vm_allocation_granularity());
3854 assert(vsn.initialize(), "Failed to setup VirtualSpaceNode");
3855
3856 // Commit some memory.
3857 size_t commit_word_size = os::vm_allocation_granularity() / BytesPerWord;
3858 bool expanded = vsn.expand_by(commit_word_size, commit_word_size);
3859 assert(expanded, "Failed to commit");
3860
3861 // Check that is_available accepts the committed size.
3862 assert_is_available_positive(commit_word_size);
3863
3864 // Check that is_available accepts half the committed size.
3865 size_t expand_word_size = commit_word_size / 2;
3866 assert_is_available_positive(expand_word_size);
3867 }
3868
3869 static void test_is_available_negative() {
3870 // Reserve some memory.
3871 VirtualSpaceNode vsn(os::vm_allocation_granularity());
3872 assert(vsn.initialize(), "Failed to setup VirtualSpaceNode");
3873
3874 // Commit some memory.
3875 size_t commit_word_size = os::vm_allocation_granularity() / BytesPerWord;
3876 bool expanded = vsn.expand_by(commit_word_size, commit_word_size);
3877 assert(expanded, "Failed to commit");
3878
3879 // Check that is_available doesn't accept a too large size.
3880 size_t two_times_commit_word_size = commit_word_size * 2;
3881 assert_is_available_negative(two_times_commit_word_size);
3882 }
3883
3884 static void test_is_available_overflow() {
3885 // Reserve some memory.
3886 VirtualSpaceNode vsn(os::vm_allocation_granularity());
3887 assert(vsn.initialize(), "Failed to setup VirtualSpaceNode");
3888
3889 // Commit some memory.
3890 size_t commit_word_size = os::vm_allocation_granularity() / BytesPerWord;
3891 bool expanded = vsn.expand_by(commit_word_size, commit_word_size);
3892 assert(expanded, "Failed to commit");
3893
3894 // Calculate a size that will overflow the virtual space size.
3895 void* virtual_space_max = (void*)(uintptr_t)-1;
3896 size_t bottom_to_max = pointer_delta(virtual_space_max, vsn.bottom(), 1);
3897 size_t overflow_size = bottom_to_max + BytesPerWord;
3898 size_t overflow_word_size = overflow_size / BytesPerWord;
3899
3900 // Check that is_available can handle the overflow.
3901 assert_is_available_negative(overflow_word_size);
3902 }
3903
3904 static void test_is_available() {
3905 TestVirtualSpaceNodeTest::test_is_available_positive();
3906 TestVirtualSpaceNodeTest::test_is_available_negative();
3907 TestVirtualSpaceNodeTest::test_is_available_overflow();
3908 }
3909 };
3910
3911 void TestVirtualSpaceNode_test() {
3912 TestVirtualSpaceNodeTest::test();
3913 TestVirtualSpaceNodeTest::test_is_available();
3914 }
3915 #endif