1 /*
2 * Copyright (c) 2011, 2015, 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.inline.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::set_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 NOT_PRODUCT(void mangle_freed_chunks();)
763 #ifdef ASSERT
764 void verify_allocated_blocks_words();
765 #endif
766
767 size_t get_raw_word_size(size_t word_size) {
768 size_t byte_size = word_size * BytesPerWord;
769
770 size_t raw_bytes_size = MAX2(byte_size, sizeof(Metablock));
771 raw_bytes_size = align_size_up(raw_bytes_size, Metachunk::object_alignment());
772
773 size_t raw_word_size = raw_bytes_size / BytesPerWord;
774 assert(raw_word_size * BytesPerWord == raw_bytes_size, "Size problem");
775
776 return raw_word_size;
777 }
778 };
779
780 uint const SpaceManager::_small_chunk_limit = 4;
781
782 const char* SpaceManager::_expand_lock_name =
783 "SpaceManager chunk allocation lock";
784 const int SpaceManager::_expand_lock_rank = Monitor::leaf - 1;
785 Mutex* const SpaceManager::_expand_lock =
786 new Mutex(SpaceManager::_expand_lock_rank,
787 SpaceManager::_expand_lock_name,
788 Mutex::_allow_vm_block_flag,
789 Monitor::_safepoint_check_never);
790
791 void VirtualSpaceNode::inc_container_count() {
792 assert_lock_strong(SpaceManager::expand_lock());
793 _container_count++;
794 DEBUG_ONLY(verify_container_count();)
795 }
796
797 void VirtualSpaceNode::dec_container_count() {
798 assert_lock_strong(SpaceManager::expand_lock());
799 _container_count--;
800 }
801
802 #ifdef ASSERT
803 void VirtualSpaceNode::verify_container_count() {
804 assert(_container_count == container_count_slow(),
805 "Inconsistency in container_count _container_count " UINTX_FORMAT
806 " container_count_slow() " UINTX_FORMAT, _container_count, container_count_slow());
807 }
808 #endif
809
810 // BlockFreelist methods
811
812 BlockFreelist::BlockFreelist() : _dictionary(new BlockTreeDictionary()) {}
813
814 BlockFreelist::~BlockFreelist() {
815 LogHandle(gc, metaspace, freelist) log;
816 if (log.is_trace()) {
817 ResourceMark rm;
818 dictionary()->print_free_lists(log.trace_stream());
819 }
820 delete _dictionary;
821 }
822
823 void BlockFreelist::return_block(MetaWord* p, size_t word_size) {
824 Metablock* free_chunk = ::new (p) Metablock(word_size);
825 dictionary()->return_chunk(free_chunk);
826 }
827
828 MetaWord* BlockFreelist::get_block(size_t word_size) {
829 if (word_size < TreeChunk<Metablock, FreeList<Metablock> >::min_size()) {
830 // Dark matter. Too small for dictionary.
831 return NULL;
832 }
833
834 Metablock* free_block =
835 dictionary()->get_chunk(word_size, FreeBlockDictionary<Metablock>::atLeast);
836 if (free_block == NULL) {
837 return NULL;
838 }
839
840 const size_t block_size = free_block->size();
841 if (block_size > WasteMultiplier * word_size) {
842 return_block((MetaWord*)free_block, block_size);
843 return NULL;
844 }
845
846 MetaWord* new_block = (MetaWord*)free_block;
847 assert(block_size >= word_size, "Incorrect size of block from freelist");
848 const size_t unused = block_size - word_size;
849 if (unused >= TreeChunk<Metablock, FreeList<Metablock> >::min_size()) {
850 return_block(new_block + word_size, unused);
851 }
852
853 return new_block;
854 }
855
856 void BlockFreelist::print_on(outputStream* st) const {
857 dictionary()->print_free_lists(st);
858 }
859
860 // VirtualSpaceNode methods
861
862 VirtualSpaceNode::~VirtualSpaceNode() {
863 _rs.release();
864 #ifdef ASSERT
865 size_t word_size = sizeof(*this) / BytesPerWord;
866 Copy::fill_to_words((HeapWord*) this, word_size, 0xf1f1f1f1);
867 #endif
868 }
869
870 size_t VirtualSpaceNode::used_words_in_vs() const {
871 return pointer_delta(top(), bottom(), sizeof(MetaWord));
872 }
873
874 // Space committed in the VirtualSpace
875 size_t VirtualSpaceNode::capacity_words_in_vs() const {
876 return pointer_delta(end(), bottom(), sizeof(MetaWord));
877 }
878
879 size_t VirtualSpaceNode::free_words_in_vs() const {
880 return pointer_delta(end(), top(), sizeof(MetaWord));
881 }
882
883 // Allocates the chunk from the virtual space only.
884 // This interface is also used internally for debugging. Not all
885 // chunks removed here are necessarily used for allocation.
886 Metachunk* VirtualSpaceNode::take_from_committed(size_t chunk_word_size) {
887 // Bottom of the new chunk
888 MetaWord* chunk_limit = top();
889 assert(chunk_limit != NULL, "Not safe to call this method");
890
891 // The virtual spaces are always expanded by the
892 // commit granularity to enforce the following condition.
893 // Without this the is_available check will not work correctly.
894 assert(_virtual_space.committed_size() == _virtual_space.actual_committed_size(),
895 "The committed memory doesn't match the expanded memory.");
896
897 if (!is_available(chunk_word_size)) {
898 LogHandle(gc, metaspace, freelist) log;
899 log.debug("VirtualSpaceNode::take_from_committed() not available " SIZE_FORMAT " words ", chunk_word_size);
900 // Dump some information about the virtual space that is nearly full
901 ResourceMark rm;
902 print_on(log.debug_stream());
903 return NULL;
904 }
905
906 // Take the space (bump top on the current virtual space).
907 inc_top(chunk_word_size);
908
909 // Initialize the chunk
910 Metachunk* result = ::new (chunk_limit) Metachunk(chunk_word_size, this);
911 return result;
912 }
913
914
915 // Expand the virtual space (commit more of the reserved space)
916 bool VirtualSpaceNode::expand_by(size_t min_words, size_t preferred_words) {
917 size_t min_bytes = min_words * BytesPerWord;
918 size_t preferred_bytes = preferred_words * BytesPerWord;
919
920 size_t uncommitted = virtual_space()->reserved_size() - virtual_space()->actual_committed_size();
921
922 if (uncommitted < min_bytes) {
923 return false;
924 }
925
926 size_t commit = MIN2(preferred_bytes, uncommitted);
927 bool result = virtual_space()->expand_by(commit, false);
928
929 assert(result, "Failed to commit memory");
930
931 return result;
932 }
933
934 Metachunk* VirtualSpaceNode::get_chunk_vs(size_t chunk_word_size) {
935 assert_lock_strong(SpaceManager::expand_lock());
936 Metachunk* result = take_from_committed(chunk_word_size);
937 if (result != NULL) {
938 inc_container_count();
939 }
940 return result;
941 }
942
943 bool VirtualSpaceNode::initialize() {
944
945 if (!_rs.is_reserved()) {
946 return false;
947 }
948
949 // These are necessary restriction to make sure that the virtual space always
950 // grows in steps of Metaspace::commit_alignment(). If both base and size are
951 // aligned only the middle alignment of the VirtualSpace is used.
952 assert_is_ptr_aligned(_rs.base(), Metaspace::commit_alignment());
953 assert_is_size_aligned(_rs.size(), Metaspace::commit_alignment());
954
955 // ReservedSpaces marked as special will have the entire memory
956 // pre-committed. Setting a committed size will make sure that
957 // committed_size and actual_committed_size agrees.
958 size_t pre_committed_size = _rs.special() ? _rs.size() : 0;
959
960 bool result = virtual_space()->initialize_with_granularity(_rs, pre_committed_size,
961 Metaspace::commit_alignment());
962 if (result) {
963 assert(virtual_space()->committed_size() == virtual_space()->actual_committed_size(),
964 "Checking that the pre-committed memory was registered by the VirtualSpace");
965
966 set_top((MetaWord*)virtual_space()->low());
967 set_reserved(MemRegion((HeapWord*)_rs.base(),
968 (HeapWord*)(_rs.base() + _rs.size())));
969
970 assert(reserved()->start() == (HeapWord*) _rs.base(),
971 "Reserved start was not set properly " PTR_FORMAT
972 " != " PTR_FORMAT, p2i(reserved()->start()), p2i(_rs.base()));
973 assert(reserved()->word_size() == _rs.size() / BytesPerWord,
974 "Reserved size was not set properly " SIZE_FORMAT
975 " != " SIZE_FORMAT, reserved()->word_size(),
976 _rs.size() / BytesPerWord);
977 }
978
979 return result;
980 }
981
982 void VirtualSpaceNode::print_on(outputStream* st) const {
983 size_t used = used_words_in_vs();
984 size_t capacity = capacity_words_in_vs();
985 VirtualSpace* vs = virtual_space();
986 st->print_cr(" space @ " PTR_FORMAT " " SIZE_FORMAT "K, " SIZE_FORMAT_W(3) "%% used "
987 "[" PTR_FORMAT ", " PTR_FORMAT ", "
988 PTR_FORMAT ", " PTR_FORMAT ")",
989 p2i(vs), capacity / K,
990 capacity == 0 ? 0 : used * 100 / capacity,
991 p2i(bottom()), p2i(top()), p2i(end()),
992 p2i(vs->high_boundary()));
993 }
994
995 #ifdef ASSERT
996 void VirtualSpaceNode::mangle() {
997 size_t word_size = capacity_words_in_vs();
998 Copy::fill_to_words((HeapWord*) low(), word_size, 0xf1f1f1f1);
999 }
1000 #endif // ASSERT
1001
1002 // VirtualSpaceList methods
1003 // Space allocated from the VirtualSpace
1004
1005 VirtualSpaceList::~VirtualSpaceList() {
1006 VirtualSpaceListIterator iter(virtual_space_list());
1007 while (iter.repeat()) {
1008 VirtualSpaceNode* vsl = iter.get_next();
1009 delete vsl;
1010 }
1011 }
1012
1013 void VirtualSpaceList::inc_reserved_words(size_t v) {
1014 assert_lock_strong(SpaceManager::expand_lock());
1015 _reserved_words = _reserved_words + v;
1016 }
1017 void VirtualSpaceList::dec_reserved_words(size_t v) {
1018 assert_lock_strong(SpaceManager::expand_lock());
1019 _reserved_words = _reserved_words - v;
1020 }
1021
1022 #define assert_committed_below_limit() \
1023 assert(MetaspaceAux::committed_bytes() <= MaxMetaspaceSize, \
1024 "Too much committed memory. Committed: " SIZE_FORMAT \
1025 " limit (MaxMetaspaceSize): " SIZE_FORMAT, \
1026 MetaspaceAux::committed_bytes(), MaxMetaspaceSize);
1027
1028 void VirtualSpaceList::inc_committed_words(size_t v) {
1029 assert_lock_strong(SpaceManager::expand_lock());
1030 _committed_words = _committed_words + v;
1031
1032 assert_committed_below_limit();
1033 }
1034 void VirtualSpaceList::dec_committed_words(size_t v) {
1035 assert_lock_strong(SpaceManager::expand_lock());
1036 _committed_words = _committed_words - v;
1037
1038 assert_committed_below_limit();
1039 }
1040
1041 void VirtualSpaceList::inc_virtual_space_count() {
1042 assert_lock_strong(SpaceManager::expand_lock());
1043 _virtual_space_count++;
1044 }
1045 void VirtualSpaceList::dec_virtual_space_count() {
1046 assert_lock_strong(SpaceManager::expand_lock());
1047 _virtual_space_count--;
1048 }
1049
1050 void ChunkManager::remove_chunk(Metachunk* chunk) {
1051 size_t word_size = chunk->word_size();
1052 ChunkIndex index = list_index(word_size);
1053 if (index != HumongousIndex) {
1054 free_chunks(index)->remove_chunk(chunk);
1055 } else {
1056 humongous_dictionary()->remove_chunk(chunk);
1057 }
1058
1059 // Chunk is being removed from the chunks free list.
1060 dec_free_chunks_total(chunk->word_size());
1061 }
1062
1063 // Walk the list of VirtualSpaceNodes and delete
1064 // nodes with a 0 container_count. Remove Metachunks in
1065 // the node from their respective freelists.
1066 void VirtualSpaceList::purge(ChunkManager* chunk_manager) {
1067 assert(SafepointSynchronize::is_at_safepoint(), "must be called at safepoint for contains to work");
1068 assert_lock_strong(SpaceManager::expand_lock());
1069 // Don't use a VirtualSpaceListIterator because this
1070 // list is being changed and a straightforward use of an iterator is not safe.
1071 VirtualSpaceNode* purged_vsl = NULL;
1072 VirtualSpaceNode* prev_vsl = virtual_space_list();
1073 VirtualSpaceNode* next_vsl = prev_vsl;
1074 while (next_vsl != NULL) {
1075 VirtualSpaceNode* vsl = next_vsl;
1076 next_vsl = vsl->next();
1077 // Don't free the current virtual space since it will likely
1078 // be needed soon.
1079 if (vsl->container_count() == 0 && vsl != current_virtual_space()) {
1080 // Unlink it from the list
1081 if (prev_vsl == vsl) {
1082 // This is the case of the current node being the first node.
1083 assert(vsl == virtual_space_list(), "Expected to be the first node");
1084 set_virtual_space_list(vsl->next());
1085 } else {
1086 prev_vsl->set_next(vsl->next());
1087 }
1088
1089 vsl->purge(chunk_manager);
1090 dec_reserved_words(vsl->reserved_words());
1091 dec_committed_words(vsl->committed_words());
1092 dec_virtual_space_count();
1093 purged_vsl = vsl;
1094 delete vsl;
1095 } else {
1096 prev_vsl = vsl;
1097 }
1098 }
1099 #ifdef ASSERT
1100 if (purged_vsl != NULL) {
1101 // List should be stable enough to use an iterator here.
1102 VirtualSpaceListIterator iter(virtual_space_list());
1103 while (iter.repeat()) {
1104 VirtualSpaceNode* vsl = iter.get_next();
1105 assert(vsl != purged_vsl, "Purge of vsl failed");
1106 }
1107 }
1108 #endif
1109 }
1110
1111
1112 // This function looks at the mmap regions in the metaspace without locking.
1113 // The chunks are added with store ordering and not deleted except for at
1114 // unloading time during a safepoint.
1115 bool VirtualSpaceList::contains(const void* ptr) {
1116 // List should be stable enough to use an iterator here because removing virtual
1117 // space nodes is only allowed at a safepoint.
1118 VirtualSpaceListIterator iter(virtual_space_list());
1119 while (iter.repeat()) {
1120 VirtualSpaceNode* vsn = iter.get_next();
1121 if (vsn->contains(ptr)) {
1122 return true;
1123 }
1124 }
1125 return false;
1126 }
1127
1128 void VirtualSpaceList::retire_current_virtual_space() {
1129 assert_lock_strong(SpaceManager::expand_lock());
1130
1131 VirtualSpaceNode* vsn = current_virtual_space();
1132
1133 ChunkManager* cm = is_class() ? Metaspace::chunk_manager_class() :
1134 Metaspace::chunk_manager_metadata();
1135
1136 vsn->retire(cm);
1137 }
1138
1139 void VirtualSpaceNode::retire(ChunkManager* chunk_manager) {
1140 for (int i = (int)MediumIndex; i >= (int)ZeroIndex; --i) {
1141 ChunkIndex index = (ChunkIndex)i;
1142 size_t chunk_size = chunk_manager->free_chunks(index)->size();
1143
1144 while (free_words_in_vs() >= chunk_size) {
1145 DEBUG_ONLY(verify_container_count();)
1146 Metachunk* chunk = get_chunk_vs(chunk_size);
1147 assert(chunk != NULL, "allocation should have been successful");
1148
1149 chunk_manager->return_chunks(index, chunk);
1150 chunk_manager->inc_free_chunks_total(chunk_size);
1151 DEBUG_ONLY(verify_container_count();)
1152 }
1153 }
1154 assert(free_words_in_vs() == 0, "should be empty now");
1155 }
1156
1157 VirtualSpaceList::VirtualSpaceList(size_t word_size) :
1158 _is_class(false),
1159 _virtual_space_list(NULL),
1160 _current_virtual_space(NULL),
1161 _reserved_words(0),
1162 _committed_words(0),
1163 _virtual_space_count(0) {
1164 MutexLockerEx cl(SpaceManager::expand_lock(),
1165 Mutex::_no_safepoint_check_flag);
1166 create_new_virtual_space(word_size);
1167 }
1168
1169 VirtualSpaceList::VirtualSpaceList(ReservedSpace rs) :
1170 _is_class(true),
1171 _virtual_space_list(NULL),
1172 _current_virtual_space(NULL),
1173 _reserved_words(0),
1174 _committed_words(0),
1175 _virtual_space_count(0) {
1176 MutexLockerEx cl(SpaceManager::expand_lock(),
1177 Mutex::_no_safepoint_check_flag);
1178 VirtualSpaceNode* class_entry = new VirtualSpaceNode(rs);
1179 bool succeeded = class_entry->initialize();
1180 if (succeeded) {
1181 link_vs(class_entry);
1182 }
1183 }
1184
1185 size_t VirtualSpaceList::free_bytes() {
1186 return virtual_space_list()->free_words_in_vs() * BytesPerWord;
1187 }
1188
1189 // Allocate another meta virtual space and add it to the list.
1190 bool VirtualSpaceList::create_new_virtual_space(size_t vs_word_size) {
1191 assert_lock_strong(SpaceManager::expand_lock());
1192
1193 if (is_class()) {
1194 assert(false, "We currently don't support more than one VirtualSpace for"
1195 " the compressed class space. The initialization of the"
1196 " CCS uses another code path and should not hit this path.");
1197 return false;
1198 }
1199
1200 if (vs_word_size == 0) {
1201 assert(false, "vs_word_size should always be at least _reserve_alignment large.");
1202 return false;
1203 }
1204
1205 // Reserve the space
1206 size_t vs_byte_size = vs_word_size * BytesPerWord;
1207 assert_is_size_aligned(vs_byte_size, Metaspace::reserve_alignment());
1208
1209 // Allocate the meta virtual space and initialize it.
1210 VirtualSpaceNode* new_entry = new VirtualSpaceNode(vs_byte_size);
1211 if (!new_entry->initialize()) {
1212 delete new_entry;
1213 return false;
1214 } else {
1215 assert(new_entry->reserved_words() == vs_word_size,
1216 "Reserved memory size differs from requested memory size");
1217 // ensure lock-free iteration sees fully initialized node
1218 OrderAccess::storestore();
1219 link_vs(new_entry);
1220 return true;
1221 }
1222 }
1223
1224 void VirtualSpaceList::link_vs(VirtualSpaceNode* new_entry) {
1225 if (virtual_space_list() == NULL) {
1226 set_virtual_space_list(new_entry);
1227 } else {
1228 current_virtual_space()->set_next(new_entry);
1229 }
1230 set_current_virtual_space(new_entry);
1231 inc_reserved_words(new_entry->reserved_words());
1232 inc_committed_words(new_entry->committed_words());
1233 inc_virtual_space_count();
1234 #ifdef ASSERT
1235 new_entry->mangle();
1236 #endif
1237 if (develop_log_is_enabled(Trace, gc, metaspace)) {
1238 LogHandle(gc, metaspace) log;
1239 VirtualSpaceNode* vsl = current_virtual_space();
1240 ResourceMark rm;
1241 vsl->print_on(log.trace_stream());
1242 }
1243 }
1244
1245 bool VirtualSpaceList::expand_node_by(VirtualSpaceNode* node,
1246 size_t min_words,
1247 size_t preferred_words) {
1248 size_t before = node->committed_words();
1249
1250 bool result = node->expand_by(min_words, preferred_words);
1251
1252 size_t after = node->committed_words();
1253
1254 // after and before can be the same if the memory was pre-committed.
1255 assert(after >= before, "Inconsistency");
1256 inc_committed_words(after - before);
1257
1258 return result;
1259 }
1260
1261 bool VirtualSpaceList::expand_by(size_t min_words, size_t preferred_words) {
1262 assert_is_size_aligned(min_words, Metaspace::commit_alignment_words());
1263 assert_is_size_aligned(preferred_words, Metaspace::commit_alignment_words());
1264 assert(min_words <= preferred_words, "Invalid arguments");
1265
1266 if (!MetaspaceGC::can_expand(min_words, this->is_class())) {
1267 return false;
1268 }
1269
1270 size_t allowed_expansion_words = MetaspaceGC::allowed_expansion();
1271 if (allowed_expansion_words < min_words) {
1272 return false;
1273 }
1274
1275 size_t max_expansion_words = MIN2(preferred_words, allowed_expansion_words);
1276
1277 // Commit more memory from the the current virtual space.
1278 bool vs_expanded = expand_node_by(current_virtual_space(),
1279 min_words,
1280 max_expansion_words);
1281 if (vs_expanded) {
1282 return true;
1283 }
1284 retire_current_virtual_space();
1285
1286 // Get another virtual space.
1287 size_t grow_vs_words = MAX2((size_t)VirtualSpaceSize, preferred_words);
1288 grow_vs_words = align_size_up(grow_vs_words, Metaspace::reserve_alignment_words());
1289
1290 if (create_new_virtual_space(grow_vs_words)) {
1291 if (current_virtual_space()->is_pre_committed()) {
1292 // The memory was pre-committed, so we are done here.
1293 assert(min_words <= current_virtual_space()->committed_words(),
1294 "The new VirtualSpace was pre-committed, so it"
1295 "should be large enough to fit the alloc request.");
1296 return true;
1297 }
1298
1299 return expand_node_by(current_virtual_space(),
1300 min_words,
1301 max_expansion_words);
1302 }
1303
1304 return false;
1305 }
1306
1307 Metachunk* VirtualSpaceList::get_new_chunk(size_t word_size,
1308 size_t grow_chunks_by_words,
1309 size_t medium_chunk_bunch) {
1310
1311 // Allocate a chunk out of the current virtual space.
1312 Metachunk* next = current_virtual_space()->get_chunk_vs(grow_chunks_by_words);
1313
1314 if (next != NULL) {
1315 return next;
1316 }
1317
1318 // The expand amount is currently only determined by the requested sizes
1319 // and not how much committed memory is left in the current virtual space.
1320
1321 size_t min_word_size = align_size_up(grow_chunks_by_words, Metaspace::commit_alignment_words());
1322 size_t preferred_word_size = align_size_up(medium_chunk_bunch, Metaspace::commit_alignment_words());
1323 if (min_word_size >= preferred_word_size) {
1324 // Can happen when humongous chunks are allocated.
1325 preferred_word_size = min_word_size;
1326 }
1327
1328 bool expanded = expand_by(min_word_size, preferred_word_size);
1329 if (expanded) {
1330 next = current_virtual_space()->get_chunk_vs(grow_chunks_by_words);
1331 assert(next != NULL, "The allocation was expected to succeed after the expansion");
1332 }
1333
1334 return next;
1335 }
1336
1337 void VirtualSpaceList::print_on(outputStream* st) const {
1338 VirtualSpaceListIterator iter(virtual_space_list());
1339 while (iter.repeat()) {
1340 VirtualSpaceNode* node = iter.get_next();
1341 node->print_on(st);
1342 }
1343 }
1344
1345 // MetaspaceGC methods
1346
1347 // VM_CollectForMetadataAllocation is the vm operation used to GC.
1348 // Within the VM operation after the GC the attempt to allocate the metadata
1349 // should succeed. If the GC did not free enough space for the metaspace
1350 // allocation, the HWM is increased so that another virtualspace will be
1351 // allocated for the metadata. With perm gen the increase in the perm
1352 // gen had bounds, MinMetaspaceExpansion and MaxMetaspaceExpansion. The
1353 // metaspace policy uses those as the small and large steps for the HWM.
1354 //
1355 // After the GC the compute_new_size() for MetaspaceGC is called to
1356 // resize the capacity of the metaspaces. The current implementation
1357 // is based on the flags MinMetaspaceFreeRatio and MaxMetaspaceFreeRatio used
1358 // to resize the Java heap by some GC's. New flags can be implemented
1359 // if really needed. MinMetaspaceFreeRatio is used to calculate how much
1360 // free space is desirable in the metaspace capacity to decide how much
1361 // to increase the HWM. MaxMetaspaceFreeRatio is used to decide how much
1362 // free space is desirable in the metaspace capacity before decreasing
1363 // the HWM.
1364
1365 // Calculate the amount to increase the high water mark (HWM).
1366 // Increase by a minimum amount (MinMetaspaceExpansion) so that
1367 // another expansion is not requested too soon. If that is not
1368 // enough to satisfy the allocation, increase by MaxMetaspaceExpansion.
1369 // If that is still not enough, expand by the size of the allocation
1370 // plus some.
1371 size_t MetaspaceGC::delta_capacity_until_GC(size_t bytes) {
1372 size_t min_delta = MinMetaspaceExpansion;
1373 size_t max_delta = MaxMetaspaceExpansion;
1374 size_t delta = align_size_up(bytes, Metaspace::commit_alignment());
1375
1376 if (delta <= min_delta) {
1377 delta = min_delta;
1378 } else if (delta <= max_delta) {
1379 // Don't want to hit the high water mark on the next
1380 // allocation so make the delta greater than just enough
1381 // for this allocation.
1382 delta = max_delta;
1383 } else {
1384 // This allocation is large but the next ones are probably not
1385 // so increase by the minimum.
1386 delta = delta + min_delta;
1387 }
1388
1389 assert_is_size_aligned(delta, Metaspace::commit_alignment());
1390
1391 return delta;
1392 }
1393
1394 size_t MetaspaceGC::capacity_until_GC() {
1395 size_t value = (size_t)OrderAccess::load_ptr_acquire(&_capacity_until_GC);
1396 assert(value >= MetaspaceSize, "Not initialized properly?");
1397 return value;
1398 }
1399
1400 bool MetaspaceGC::inc_capacity_until_GC(size_t v, size_t* new_cap_until_GC, size_t* old_cap_until_GC) {
1401 assert_is_size_aligned(v, Metaspace::commit_alignment());
1402
1403 size_t capacity_until_GC = (size_t) _capacity_until_GC;
1404 size_t new_value = capacity_until_GC + v;
1405
1406 if (new_value < capacity_until_GC) {
1407 // The addition wrapped around, set new_value to aligned max value.
1408 new_value = align_size_down(max_uintx, Metaspace::commit_alignment());
1409 }
1410
1411 intptr_t expected = (intptr_t) capacity_until_GC;
1412 intptr_t actual = Atomic::cmpxchg_ptr((intptr_t) new_value, &_capacity_until_GC, expected);
1413
1414 if (expected != actual) {
1415 return false;
1416 }
1417
1418 if (new_cap_until_GC != NULL) {
1419 *new_cap_until_GC = new_value;
1420 }
1421 if (old_cap_until_GC != NULL) {
1422 *old_cap_until_GC = capacity_until_GC;
1423 }
1424 return true;
1425 }
1426
1427 size_t MetaspaceGC::dec_capacity_until_GC(size_t v) {
1428 assert_is_size_aligned(v, Metaspace::commit_alignment());
1429
1430 return (size_t)Atomic::add_ptr(-(intptr_t)v, &_capacity_until_GC);
1431 }
1432
1433 void MetaspaceGC::initialize() {
1434 // Set the high-water mark to MaxMetapaceSize during VM initializaton since
1435 // we can't do a GC during initialization.
1436 _capacity_until_GC = MaxMetaspaceSize;
1437 }
1438
1439 void MetaspaceGC::post_initialize() {
1440 // Reset the high-water mark once the VM initialization is done.
1441 _capacity_until_GC = MAX2(MetaspaceAux::committed_bytes(), MetaspaceSize);
1442 }
1443
1444 bool MetaspaceGC::can_expand(size_t word_size, bool is_class) {
1445 // Check if the compressed class space is full.
1446 if (is_class && Metaspace::using_class_space()) {
1447 size_t class_committed = MetaspaceAux::committed_bytes(Metaspace::ClassType);
1448 if (class_committed + word_size * BytesPerWord > CompressedClassSpaceSize) {
1449 return false;
1450 }
1451 }
1452
1453 // Check if the user has imposed a limit on the metaspace memory.
1454 size_t committed_bytes = MetaspaceAux::committed_bytes();
1455 if (committed_bytes + word_size * BytesPerWord > MaxMetaspaceSize) {
1456 return false;
1457 }
1458
1459 return true;
1460 }
1461
1462 size_t MetaspaceGC::allowed_expansion() {
1463 size_t committed_bytes = MetaspaceAux::committed_bytes();
1464 size_t capacity_until_gc = capacity_until_GC();
1465
1466 assert(capacity_until_gc >= committed_bytes,
1467 "capacity_until_gc: " SIZE_FORMAT " < committed_bytes: " SIZE_FORMAT,
1468 capacity_until_gc, committed_bytes);
1469
1470 size_t left_until_max = MaxMetaspaceSize - committed_bytes;
1471 size_t left_until_GC = capacity_until_gc - committed_bytes;
1472 size_t left_to_commit = MIN2(left_until_GC, left_until_max);
1473
1474 return left_to_commit / BytesPerWord;
1475 }
1476
1477 void MetaspaceGC::compute_new_size() {
1478 assert(_shrink_factor <= 100, "invalid shrink factor");
1479 uint current_shrink_factor = _shrink_factor;
1480 _shrink_factor = 0;
1481
1482 // Using committed_bytes() for used_after_gc is an overestimation, since the
1483 // chunk free lists are included in committed_bytes() and the memory in an
1484 // un-fragmented chunk free list is available for future allocations.
1485 // However, if the chunk free lists becomes fragmented, then the memory may
1486 // not be available for future allocations and the memory is therefore "in use".
1487 // Including the chunk free lists in the definition of "in use" is therefore
1488 // necessary. Not including the chunk free lists can cause capacity_until_GC to
1489 // shrink below committed_bytes() and this has caused serious bugs in the past.
1490 const size_t used_after_gc = MetaspaceAux::committed_bytes();
1491 const size_t capacity_until_GC = MetaspaceGC::capacity_until_GC();
1492
1493 const double minimum_free_percentage = MinMetaspaceFreeRatio / 100.0;
1494 const double maximum_used_percentage = 1.0 - minimum_free_percentage;
1495
1496 const double min_tmp = used_after_gc / maximum_used_percentage;
1497 size_t minimum_desired_capacity =
1498 (size_t)MIN2(min_tmp, double(max_uintx));
1499 // Don't shrink less than the initial generation size
1500 minimum_desired_capacity = MAX2(minimum_desired_capacity,
1501 MetaspaceSize);
1502
1503 log_trace(gc, metaspace)("MetaspaceGC::compute_new_size: ");
1504 log_trace(gc, metaspace)(" minimum_free_percentage: %6.2f maximum_used_percentage: %6.2f",
1505 minimum_free_percentage, maximum_used_percentage);
1506 log_trace(gc, metaspace)(" used_after_gc : %6.1fKB", used_after_gc / (double) K);
1507
1508
1509 size_t shrink_bytes = 0;
1510 if (capacity_until_GC < minimum_desired_capacity) {
1511 // If we have less capacity below the metaspace HWM, then
1512 // increment the HWM.
1513 size_t expand_bytes = minimum_desired_capacity - capacity_until_GC;
1514 expand_bytes = align_size_up(expand_bytes, Metaspace::commit_alignment());
1515 // Don't expand unless it's significant
1516 if (expand_bytes >= MinMetaspaceExpansion) {
1517 size_t new_capacity_until_GC = 0;
1518 bool succeeded = MetaspaceGC::inc_capacity_until_GC(expand_bytes, &new_capacity_until_GC);
1519 assert(succeeded, "Should always succesfully increment HWM when at safepoint");
1520
1521 Metaspace::tracer()->report_gc_threshold(capacity_until_GC,
1522 new_capacity_until_GC,
1523 MetaspaceGCThresholdUpdater::ComputeNewSize);
1524 log_trace(gc, metaspace)(" expanding: minimum_desired_capacity: %6.1fKB expand_bytes: %6.1fKB MinMetaspaceExpansion: %6.1fKB new metaspace HWM: %6.1fKB",
1525 minimum_desired_capacity / (double) K,
1526 expand_bytes / (double) K,
1527 MinMetaspaceExpansion / (double) K,
1528 new_capacity_until_GC / (double) K);
1529 }
1530 return;
1531 }
1532
1533 // No expansion, now see if we want to shrink
1534 // We would never want to shrink more than this
1535 assert(capacity_until_GC >= minimum_desired_capacity,
1536 SIZE_FORMAT " >= " SIZE_FORMAT,
1537 capacity_until_GC, minimum_desired_capacity);
1538 size_t max_shrink_bytes = capacity_until_GC - minimum_desired_capacity;
1539
1540 // Should shrinking be considered?
1541 if (MaxMetaspaceFreeRatio < 100) {
1542 const double maximum_free_percentage = MaxMetaspaceFreeRatio / 100.0;
1543 const double minimum_used_percentage = 1.0 - maximum_free_percentage;
1544 const double max_tmp = used_after_gc / minimum_used_percentage;
1545 size_t maximum_desired_capacity = (size_t)MIN2(max_tmp, double(max_uintx));
1546 maximum_desired_capacity = MAX2(maximum_desired_capacity,
1547 MetaspaceSize);
1548 log_trace(gc, metaspace)(" maximum_free_percentage: %6.2f minimum_used_percentage: %6.2f",
1549 maximum_free_percentage, minimum_used_percentage);
1550 log_trace(gc, metaspace)(" minimum_desired_capacity: %6.1fKB maximum_desired_capacity: %6.1fKB",
1551 minimum_desired_capacity / (double) K, maximum_desired_capacity / (double) K);
1552
1553 assert(minimum_desired_capacity <= maximum_desired_capacity,
1554 "sanity check");
1555
1556 if (capacity_until_GC > maximum_desired_capacity) {
1557 // Capacity too large, compute shrinking size
1558 shrink_bytes = capacity_until_GC - maximum_desired_capacity;
1559 // We don't want shrink all the way back to initSize if people call
1560 // System.gc(), because some programs do that between "phases" and then
1561 // we'd just have to grow the heap up again for the next phase. So we
1562 // damp the shrinking: 0% on the first call, 10% on the second call, 40%
1563 // on the third call, and 100% by the fourth call. But if we recompute
1564 // size without shrinking, it goes back to 0%.
1565 shrink_bytes = shrink_bytes / 100 * current_shrink_factor;
1566
1567 shrink_bytes = align_size_down(shrink_bytes, Metaspace::commit_alignment());
1568
1569 assert(shrink_bytes <= max_shrink_bytes,
1570 "invalid shrink size " SIZE_FORMAT " not <= " SIZE_FORMAT,
1571 shrink_bytes, max_shrink_bytes);
1572 if (current_shrink_factor == 0) {
1573 _shrink_factor = 10;
1574 } else {
1575 _shrink_factor = MIN2(current_shrink_factor * 4, (uint) 100);
1576 }
1577 log_trace(gc, metaspace)(" shrinking: initSize: %.1fK maximum_desired_capacity: %.1fK",
1578 MetaspaceSize / (double) K, maximum_desired_capacity / (double) K);
1579 log_trace(gc, metaspace)(" shrink_bytes: %.1fK current_shrink_factor: %d new shrink factor: %d MinMetaspaceExpansion: %.1fK",
1580 shrink_bytes / (double) K, current_shrink_factor, _shrink_factor, MinMetaspaceExpansion / (double) K);
1581 }
1582 }
1583
1584 // Don't shrink unless it's significant
1585 if (shrink_bytes >= MinMetaspaceExpansion &&
1586 ((capacity_until_GC - shrink_bytes) >= MetaspaceSize)) {
1587 size_t new_capacity_until_GC = MetaspaceGC::dec_capacity_until_GC(shrink_bytes);
1588 Metaspace::tracer()->report_gc_threshold(capacity_until_GC,
1589 new_capacity_until_GC,
1590 MetaspaceGCThresholdUpdater::ComputeNewSize);
1591 }
1592 }
1593
1594 // Metadebug methods
1595
1596 void Metadebug::init_allocation_fail_alot_count() {
1597 if (MetadataAllocationFailALot) {
1598 _allocation_fail_alot_count =
1599 1+(long)((double)MetadataAllocationFailALotInterval*os::random()/(max_jint+1.0));
1600 }
1601 }
1602
1603 #ifdef ASSERT
1604 bool Metadebug::test_metadata_failure() {
1605 if (MetadataAllocationFailALot &&
1606 Threads::is_vm_complete()) {
1607 if (_allocation_fail_alot_count > 0) {
1608 _allocation_fail_alot_count--;
1609 } else {
1610 log_trace(gc, metaspace, freelist)("Metadata allocation failing for MetadataAllocationFailALot");
1611 init_allocation_fail_alot_count();
1612 return true;
1613 }
1614 }
1615 return false;
1616 }
1617 #endif
1618
1619 // ChunkManager methods
1620
1621 size_t ChunkManager::free_chunks_total_words() {
1622 return _free_chunks_total;
1623 }
1624
1625 size_t ChunkManager::free_chunks_total_bytes() {
1626 return free_chunks_total_words() * BytesPerWord;
1627 }
1628
1629 size_t ChunkManager::free_chunks_count() {
1630 #ifdef ASSERT
1631 if (!UseConcMarkSweepGC && !SpaceManager::expand_lock()->is_locked()) {
1632 MutexLockerEx cl(SpaceManager::expand_lock(),
1633 Mutex::_no_safepoint_check_flag);
1634 // This lock is only needed in debug because the verification
1635 // of the _free_chunks_totals walks the list of free chunks
1636 slow_locked_verify_free_chunks_count();
1637 }
1638 #endif
1639 return _free_chunks_count;
1640 }
1641
1642 void ChunkManager::locked_verify_free_chunks_total() {
1643 assert_lock_strong(SpaceManager::expand_lock());
1644 assert(sum_free_chunks() == _free_chunks_total,
1645 "_free_chunks_total " SIZE_FORMAT " is not the"
1646 " same as sum " SIZE_FORMAT, _free_chunks_total,
1647 sum_free_chunks());
1648 }
1649
1650 void ChunkManager::verify_free_chunks_total() {
1651 MutexLockerEx cl(SpaceManager::expand_lock(),
1652 Mutex::_no_safepoint_check_flag);
1653 locked_verify_free_chunks_total();
1654 }
1655
1656 void ChunkManager::locked_verify_free_chunks_count() {
1657 assert_lock_strong(SpaceManager::expand_lock());
1658 assert(sum_free_chunks_count() == _free_chunks_count,
1659 "_free_chunks_count " SIZE_FORMAT " is not the"
1660 " same as sum " SIZE_FORMAT, _free_chunks_count,
1661 sum_free_chunks_count());
1662 }
1663
1664 void ChunkManager::verify_free_chunks_count() {
1665 #ifdef ASSERT
1666 MutexLockerEx cl(SpaceManager::expand_lock(),
1667 Mutex::_no_safepoint_check_flag);
1668 locked_verify_free_chunks_count();
1669 #endif
1670 }
1671
1672 void ChunkManager::verify() {
1673 MutexLockerEx cl(SpaceManager::expand_lock(),
1674 Mutex::_no_safepoint_check_flag);
1675 locked_verify();
1676 }
1677
1678 void ChunkManager::locked_verify() {
1679 locked_verify_free_chunks_count();
1680 locked_verify_free_chunks_total();
1681 }
1682
1683 void ChunkManager::locked_print_free_chunks(outputStream* st) {
1684 assert_lock_strong(SpaceManager::expand_lock());
1685 st->print_cr("Free chunk total " SIZE_FORMAT " count " SIZE_FORMAT,
1686 _free_chunks_total, _free_chunks_count);
1687 }
1688
1689 void ChunkManager::locked_print_sum_free_chunks(outputStream* st) {
1690 assert_lock_strong(SpaceManager::expand_lock());
1691 st->print_cr("Sum free chunk total " SIZE_FORMAT " count " SIZE_FORMAT,
1692 sum_free_chunks(), sum_free_chunks_count());
1693 }
1694 ChunkList* ChunkManager::free_chunks(ChunkIndex index) {
1695 return &_free_chunks[index];
1696 }
1697
1698 // These methods that sum the free chunk lists are used in printing
1699 // methods that are used in product builds.
1700 size_t ChunkManager::sum_free_chunks() {
1701 assert_lock_strong(SpaceManager::expand_lock());
1702 size_t result = 0;
1703 for (ChunkIndex i = ZeroIndex; i < NumberOfFreeLists; i = next_chunk_index(i)) {
1704 ChunkList* list = free_chunks(i);
1705
1706 if (list == NULL) {
1707 continue;
1708 }
1709
1710 result = result + list->count() * list->size();
1711 }
1712 result = result + humongous_dictionary()->total_size();
1713 return result;
1714 }
1715
1716 size_t ChunkManager::sum_free_chunks_count() {
1717 assert_lock_strong(SpaceManager::expand_lock());
1718 size_t count = 0;
1719 for (ChunkIndex i = ZeroIndex; i < NumberOfFreeLists; i = next_chunk_index(i)) {
1720 ChunkList* list = free_chunks(i);
1721 if (list == NULL) {
1722 continue;
1723 }
1724 count = count + list->count();
1725 }
1726 count = count + humongous_dictionary()->total_free_blocks();
1727 return count;
1728 }
1729
1730 ChunkList* ChunkManager::find_free_chunks_list(size_t word_size) {
1731 ChunkIndex index = list_index(word_size);
1732 assert(index < HumongousIndex, "No humongous list");
1733 return free_chunks(index);
1734 }
1735
1736 Metachunk* ChunkManager::free_chunks_get(size_t word_size) {
1737 assert_lock_strong(SpaceManager::expand_lock());
1738
1739 slow_locked_verify();
1740
1741 Metachunk* chunk = NULL;
1742 if (list_index(word_size) != HumongousIndex) {
1743 ChunkList* free_list = find_free_chunks_list(word_size);
1744 assert(free_list != NULL, "Sanity check");
1745
1746 chunk = free_list->head();
1747
1748 if (chunk == NULL) {
1749 return NULL;
1750 }
1751
1752 // Remove the chunk as the head of the list.
1753 free_list->remove_chunk(chunk);
1754
1755 log_trace(gc, metaspace, freelist)("ChunkManager::free_chunks_get: free_list " PTR_FORMAT " head " PTR_FORMAT " size " SIZE_FORMAT,
1756 p2i(free_list), p2i(chunk), chunk->word_size());
1757 } else {
1758 chunk = humongous_dictionary()->get_chunk(
1759 word_size,
1760 FreeBlockDictionary<Metachunk>::atLeast);
1761
1762 if (chunk == NULL) {
1763 return NULL;
1764 }
1765
1766 log_debug(gc, metaspace, alloc)("Free list allocate humongous chunk size " SIZE_FORMAT " for requested size " SIZE_FORMAT " waste " SIZE_FORMAT,
1767 chunk->word_size(), word_size, chunk->word_size() - word_size);
1768 }
1769
1770 // Chunk is being removed from the chunks free list.
1771 dec_free_chunks_total(chunk->word_size());
1772
1773 // Remove it from the links to this freelist
1774 chunk->set_next(NULL);
1775 chunk->set_prev(NULL);
1776 #ifdef ASSERT
1777 // Chunk is no longer on any freelist. Setting to false make container_count_slow()
1778 // work.
1779 chunk->set_is_tagged_free(false);
1780 #endif
1781 chunk->container()->inc_container_count();
1782
1783 slow_locked_verify();
1784 return chunk;
1785 }
1786
1787 Metachunk* ChunkManager::chunk_freelist_allocate(size_t word_size) {
1788 assert_lock_strong(SpaceManager::expand_lock());
1789 slow_locked_verify();
1790
1791 // Take from the beginning of the list
1792 Metachunk* chunk = free_chunks_get(word_size);
1793 if (chunk == NULL) {
1794 return NULL;
1795 }
1796
1797 assert((word_size <= chunk->word_size()) ||
1798 list_index(chunk->word_size() == HumongousIndex),
1799 "Non-humongous variable sized chunk");
1800 LogHandle(gc, metaspace, freelist) log;
1801 if (log.is_debug()) {
1802 size_t list_count;
1803 if (list_index(word_size) < HumongousIndex) {
1804 ChunkList* list = find_free_chunks_list(word_size);
1805 list_count = list->count();
1806 } else {
1807 list_count = humongous_dictionary()->total_count();
1808 }
1809 log.debug("ChunkManager::chunk_freelist_allocate: " PTR_FORMAT " chunk " PTR_FORMAT " size " SIZE_FORMAT " count " SIZE_FORMAT " ",
1810 p2i(this), p2i(chunk), chunk->word_size(), list_count);
1811 ResourceMark rm;
1812 locked_print_free_chunks(log.debug_stream());
1813 }
1814
1815 return chunk;
1816 }
1817
1818 void ChunkManager::print_on(outputStream* out) const {
1819 const_cast<ChunkManager *>(this)->humongous_dictionary()->report_statistics(out);
1820 }
1821
1822 // SpaceManager methods
1823
1824 void SpaceManager::get_initial_chunk_sizes(Metaspace::MetaspaceType type,
1825 size_t* chunk_word_size,
1826 size_t* class_chunk_word_size) {
1827 switch (type) {
1828 case Metaspace::BootMetaspaceType:
1829 *chunk_word_size = Metaspace::first_chunk_word_size();
1830 *class_chunk_word_size = Metaspace::first_class_chunk_word_size();
1831 break;
1832 case Metaspace::ROMetaspaceType:
1833 *chunk_word_size = SharedReadOnlySize / wordSize;
1834 *class_chunk_word_size = ClassSpecializedChunk;
1835 break;
1836 case Metaspace::ReadWriteMetaspaceType:
1837 *chunk_word_size = SharedReadWriteSize / wordSize;
1838 *class_chunk_word_size = ClassSpecializedChunk;
1839 break;
1840 case Metaspace::AnonymousMetaspaceType:
1841 case Metaspace::ReflectionMetaspaceType:
1842 *chunk_word_size = SpecializedChunk;
1843 *class_chunk_word_size = ClassSpecializedChunk;
1844 break;
1845 default:
1846 *chunk_word_size = SmallChunk;
1847 *class_chunk_word_size = ClassSmallChunk;
1848 break;
1849 }
1850 assert(*chunk_word_size != 0 && *class_chunk_word_size != 0,
1851 "Initial chunks sizes bad: data " SIZE_FORMAT
1852 " class " SIZE_FORMAT,
1853 *chunk_word_size, *class_chunk_word_size);
1854 }
1855
1856 size_t SpaceManager::sum_free_in_chunks_in_use() const {
1857 MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag);
1858 size_t free = 0;
1859 for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) {
1860 Metachunk* chunk = chunks_in_use(i);
1861 while (chunk != NULL) {
1862 free += chunk->free_word_size();
1863 chunk = chunk->next();
1864 }
1865 }
1866 return free;
1867 }
1868
1869 size_t SpaceManager::sum_waste_in_chunks_in_use() const {
1870 MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag);
1871 size_t result = 0;
1872 for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) {
1873 result += sum_waste_in_chunks_in_use(i);
1874 }
1875
1876 return result;
1877 }
1878
1879 size_t SpaceManager::sum_waste_in_chunks_in_use(ChunkIndex index) const {
1880 size_t result = 0;
1881 Metachunk* chunk = chunks_in_use(index);
1882 // Count the free space in all the chunk but not the
1883 // current chunk from which allocations are still being done.
1884 while (chunk != NULL) {
1885 if (chunk != current_chunk()) {
1886 result += chunk->free_word_size();
1887 }
1888 chunk = chunk->next();
1889 }
1890 return result;
1891 }
1892
1893 size_t SpaceManager::sum_capacity_in_chunks_in_use() const {
1894 // For CMS use "allocated_chunks_words()" which does not need the
1895 // Metaspace lock. For the other collectors sum over the
1896 // lists. Use both methods as a check that "allocated_chunks_words()"
1897 // is correct. That is, sum_capacity_in_chunks() is too expensive
1898 // to use in the product and allocated_chunks_words() should be used
1899 // but allow for checking that allocated_chunks_words() returns the same
1900 // value as sum_capacity_in_chunks_in_use() which is the definitive
1901 // answer.
1902 if (UseConcMarkSweepGC) {
1903 return allocated_chunks_words();
1904 } else {
1905 MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag);
1906 size_t sum = 0;
1907 for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) {
1908 Metachunk* chunk = chunks_in_use(i);
1909 while (chunk != NULL) {
1910 sum += chunk->word_size();
1911 chunk = chunk->next();
1912 }
1913 }
1914 return sum;
1915 }
1916 }
1917
1918 size_t SpaceManager::sum_count_in_chunks_in_use() {
1919 size_t count = 0;
1920 for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) {
1921 count = count + sum_count_in_chunks_in_use(i);
1922 }
1923
1924 return count;
1925 }
1926
1927 size_t SpaceManager::sum_count_in_chunks_in_use(ChunkIndex i) {
1928 size_t count = 0;
1929 Metachunk* chunk = chunks_in_use(i);
1930 while (chunk != NULL) {
1931 count++;
1932 chunk = chunk->next();
1933 }
1934 return count;
1935 }
1936
1937
1938 size_t SpaceManager::sum_used_in_chunks_in_use() const {
1939 MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag);
1940 size_t used = 0;
1941 for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) {
1942 Metachunk* chunk = chunks_in_use(i);
1943 while (chunk != NULL) {
1944 used += chunk->used_word_size();
1945 chunk = chunk->next();
1946 }
1947 }
1948 return used;
1949 }
1950
1951 void SpaceManager::locked_print_chunks_in_use_on(outputStream* st) const {
1952
1953 for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) {
1954 Metachunk* chunk = chunks_in_use(i);
1955 st->print("SpaceManager: %s " PTR_FORMAT,
1956 chunk_size_name(i), p2i(chunk));
1957 if (chunk != NULL) {
1958 st->print_cr(" free " SIZE_FORMAT,
1959 chunk->free_word_size());
1960 } else {
1961 st->cr();
1962 }
1963 }
1964
1965 chunk_manager()->locked_print_free_chunks(st);
1966 chunk_manager()->locked_print_sum_free_chunks(st);
1967 }
1968
1969 size_t SpaceManager::calc_chunk_size(size_t word_size) {
1970
1971 // Decide between a small chunk and a medium chunk. Up to
1972 // _small_chunk_limit small chunks can be allocated.
1973 // After that a medium chunk is preferred.
1974 size_t chunk_word_size;
1975 if (chunks_in_use(MediumIndex) == NULL &&
1976 sum_count_in_chunks_in_use(SmallIndex) < _small_chunk_limit) {
1977 chunk_word_size = (size_t) small_chunk_size();
1978 if (word_size + Metachunk::overhead() > small_chunk_size()) {
1979 chunk_word_size = medium_chunk_size();
1980 }
1981 } else {
1982 chunk_word_size = medium_chunk_size();
1983 }
1984
1985 // Might still need a humongous chunk. Enforce
1986 // humongous allocations sizes to be aligned up to
1987 // the smallest chunk size.
1988 size_t if_humongous_sized_chunk =
1989 align_size_up(word_size + Metachunk::overhead(),
1990 smallest_chunk_size());
1991 chunk_word_size =
1992 MAX2((size_t) chunk_word_size, if_humongous_sized_chunk);
1993
1994 assert(!SpaceManager::is_humongous(word_size) ||
1995 chunk_word_size == if_humongous_sized_chunk,
1996 "Size calculation is wrong, word_size " SIZE_FORMAT
1997 " chunk_word_size " SIZE_FORMAT,
1998 word_size, chunk_word_size);
1999 LogHandle(gc, metaspace, alloc) log;
2000 if (log.is_debug() && SpaceManager::is_humongous(word_size)) {
2001 log.debug("Metadata humongous allocation:");
2002 log.debug(" word_size " PTR_FORMAT, word_size);
2003 log.debug(" chunk_word_size " PTR_FORMAT, chunk_word_size);
2004 log.debug(" chunk overhead " PTR_FORMAT, Metachunk::overhead());
2005 }
2006 return chunk_word_size;
2007 }
2008
2009 void SpaceManager::track_metaspace_memory_usage() {
2010 if (is_init_completed()) {
2011 if (is_class()) {
2012 MemoryService::track_compressed_class_memory_usage();
2013 }
2014 MemoryService::track_metaspace_memory_usage();
2015 }
2016 }
2017
2018 MetaWord* SpaceManager::grow_and_allocate(size_t word_size) {
2019 assert(vs_list()->current_virtual_space() != NULL,
2020 "Should have been set");
2021 assert(current_chunk() == NULL ||
2022 current_chunk()->allocate(word_size) == NULL,
2023 "Don't need to expand");
2024 MutexLockerEx cl(SpaceManager::expand_lock(), Mutex::_no_safepoint_check_flag);
2025
2026 if (log_is_enabled(Trace, gc, metaspace, freelist)) {
2027 size_t words_left = 0;
2028 size_t words_used = 0;
2029 if (current_chunk() != NULL) {
2030 words_left = current_chunk()->free_word_size();
2031 words_used = current_chunk()->used_word_size();
2032 }
2033 log_trace(gc, metaspace, freelist)("SpaceManager::grow_and_allocate for " SIZE_FORMAT " words " SIZE_FORMAT " words used " SIZE_FORMAT " words left",
2034 word_size, words_used, words_left);
2035 }
2036
2037 // Get another chunk
2038 size_t grow_chunks_by_words = calc_chunk_size(word_size);
2039 Metachunk* next = get_new_chunk(word_size, grow_chunks_by_words);
2040
2041 MetaWord* mem = NULL;
2042
2043 // If a chunk was available, add it to the in-use chunk list
2044 // and do an allocation from it.
2045 if (next != NULL) {
2046 // Add to this manager's list of chunks in use.
2047 add_chunk(next, false);
2048 mem = next->allocate(word_size);
2049 }
2050
2051 // Track metaspace memory usage statistic.
2052 track_metaspace_memory_usage();
2053
2054 return mem;
2055 }
2056
2057 void SpaceManager::print_on(outputStream* st) const {
2058
2059 for (ChunkIndex i = ZeroIndex;
2060 i < NumberOfInUseLists ;
2061 i = next_chunk_index(i) ) {
2062 st->print_cr(" chunks_in_use " PTR_FORMAT " chunk size " SIZE_FORMAT,
2063 p2i(chunks_in_use(i)),
2064 chunks_in_use(i) == NULL ? 0 : chunks_in_use(i)->word_size());
2065 }
2066 st->print_cr(" waste: Small " SIZE_FORMAT " Medium " SIZE_FORMAT
2067 " Humongous " SIZE_FORMAT,
2068 sum_waste_in_chunks_in_use(SmallIndex),
2069 sum_waste_in_chunks_in_use(MediumIndex),
2070 sum_waste_in_chunks_in_use(HumongousIndex));
2071 // block free lists
2072 if (block_freelists() != NULL) {
2073 st->print_cr("total in block free lists " SIZE_FORMAT,
2074 block_freelists()->total_size());
2075 }
2076 }
2077
2078 SpaceManager::SpaceManager(Metaspace::MetadataType mdtype,
2079 Mutex* lock) :
2080 _mdtype(mdtype),
2081 _allocated_blocks_words(0),
2082 _allocated_chunks_words(0),
2083 _allocated_chunks_count(0),
2084 _lock(lock)
2085 {
2086 initialize();
2087 }
2088
2089 void SpaceManager::inc_size_metrics(size_t words) {
2090 assert_lock_strong(SpaceManager::expand_lock());
2091 // Total of allocated Metachunks and allocated Metachunks count
2092 // for each SpaceManager
2093 _allocated_chunks_words = _allocated_chunks_words + words;
2094 _allocated_chunks_count++;
2095 // Global total of capacity in allocated Metachunks
2096 MetaspaceAux::inc_capacity(mdtype(), words);
2097 // Global total of allocated Metablocks.
2098 // used_words_slow() includes the overhead in each
2099 // Metachunk so include it in the used when the
2100 // Metachunk is first added (so only added once per
2101 // Metachunk).
2102 MetaspaceAux::inc_used(mdtype(), Metachunk::overhead());
2103 }
2104
2105 void SpaceManager::inc_used_metrics(size_t words) {
2106 // Add to the per SpaceManager total
2107 Atomic::add_ptr(words, &_allocated_blocks_words);
2108 // Add to the global total
2109 MetaspaceAux::inc_used(mdtype(), words);
2110 }
2111
2112 void SpaceManager::dec_total_from_size_metrics() {
2113 MetaspaceAux::dec_capacity(mdtype(), allocated_chunks_words());
2114 MetaspaceAux::dec_used(mdtype(), allocated_blocks_words());
2115 // Also deduct the overhead per Metachunk
2116 MetaspaceAux::dec_used(mdtype(), allocated_chunks_count() * Metachunk::overhead());
2117 }
2118
2119 void SpaceManager::initialize() {
2120 Metadebug::init_allocation_fail_alot_count();
2121 for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) {
2122 _chunks_in_use[i] = NULL;
2123 }
2124 _current_chunk = NULL;
2125 log_trace(gc, metaspace, freelist)("SpaceManager(): " PTR_FORMAT, p2i(this));
2126 }
2127
2128 void ChunkManager::return_chunks(ChunkIndex index, Metachunk* chunks) {
2129 if (chunks == NULL) {
2130 return;
2131 }
2132 ChunkList* list = free_chunks(index);
2133 assert(list->size() == chunks->word_size(), "Mismatch in chunk sizes");
2134 assert_lock_strong(SpaceManager::expand_lock());
2135 Metachunk* cur = chunks;
2136
2137 // This returns chunks one at a time. If a new
2138 // class List can be created that is a base class
2139 // of FreeList then something like FreeList::prepend()
2140 // can be used in place of this loop
2141 while (cur != NULL) {
2142 assert(cur->container() != NULL, "Container should have been set");
2143 cur->container()->dec_container_count();
2144 // Capture the next link before it is changed
2145 // by the call to return_chunk_at_head();
2146 Metachunk* next = cur->next();
2147 DEBUG_ONLY(cur->set_is_tagged_free(true);)
2148 list->return_chunk_at_head(cur);
2149 cur = next;
2150 }
2151 }
2152
2153 SpaceManager::~SpaceManager() {
2154 // This call this->_lock which can't be done while holding expand_lock()
2155 assert(sum_capacity_in_chunks_in_use() == allocated_chunks_words(),
2156 "sum_capacity_in_chunks_in_use() " SIZE_FORMAT
2157 " allocated_chunks_words() " SIZE_FORMAT,
2158 sum_capacity_in_chunks_in_use(), allocated_chunks_words());
2159
2160 MutexLockerEx fcl(SpaceManager::expand_lock(),
2161 Mutex::_no_safepoint_check_flag);
2162
2163 chunk_manager()->slow_locked_verify();
2164
2165 dec_total_from_size_metrics();
2166
2167 LogHandle(gc, metaspace, freelist) log;
2168 if (log.is_trace()) {
2169 log.trace("~SpaceManager(): " PTR_FORMAT, p2i(this));
2170 ResourceMark rm;
2171 locked_print_chunks_in_use_on(log.trace_stream());
2172 }
2173
2174 // Do not mangle freed Metachunks. The chunk size inside Metachunks
2175 // is during the freeing of a VirtualSpaceNodes.
2176
2177 // Have to update before the chunks_in_use lists are emptied
2178 // below.
2179 chunk_manager()->inc_free_chunks_total(allocated_chunks_words(),
2180 sum_count_in_chunks_in_use());
2181
2182 // Add all the chunks in use by this space manager
2183 // to the global list of free chunks.
2184
2185 // Follow each list of chunks-in-use and add them to the
2186 // free lists. Each list is NULL terminated.
2187
2188 for (ChunkIndex i = ZeroIndex; i < HumongousIndex; i = next_chunk_index(i)) {
2189 log.trace("returned " SIZE_FORMAT " %s chunks to freelist", sum_count_in_chunks_in_use(i), chunk_size_name(i));
2190 Metachunk* chunks = chunks_in_use(i);
2191 chunk_manager()->return_chunks(i, chunks);
2192 set_chunks_in_use(i, NULL);
2193 log.trace("updated freelist count " SSIZE_FORMAT " %s", chunk_manager()->free_chunks(i)->count(), chunk_size_name(i));
2194 assert(i != HumongousIndex, "Humongous chunks are handled explicitly later");
2195 }
2196
2197 // The medium chunk case may be optimized by passing the head and
2198 // tail of the medium chunk list to add_at_head(). The tail is often
2199 // the current chunk but there are probably exceptions.
2200
2201 // Humongous chunks
2202 log.trace("returned " SIZE_FORMAT " %s humongous chunks to dictionary",
2203 sum_count_in_chunks_in_use(HumongousIndex), chunk_size_name(HumongousIndex));
2204 log.trace("Humongous chunk dictionary: ");
2205 // Humongous chunks are never the current chunk.
2206 Metachunk* humongous_chunks = chunks_in_use(HumongousIndex);
2207
2208 while (humongous_chunks != NULL) {
2209 #ifdef ASSERT
2210 humongous_chunks->set_is_tagged_free(true);
2211 #endif
2212 log.trace(PTR_FORMAT " (" SIZE_FORMAT ") ", p2i(humongous_chunks), humongous_chunks->word_size());
2213 assert(humongous_chunks->word_size() == (size_t)
2214 align_size_up(humongous_chunks->word_size(),
2215 smallest_chunk_size()),
2216 "Humongous chunk size is wrong: word size " SIZE_FORMAT
2217 " granularity " SIZE_FORMAT,
2218 humongous_chunks->word_size(), smallest_chunk_size());
2219 Metachunk* next_humongous_chunks = humongous_chunks->next();
2220 humongous_chunks->container()->dec_container_count();
2221 chunk_manager()->humongous_dictionary()->return_chunk(humongous_chunks);
2222 humongous_chunks = next_humongous_chunks;
2223 }
2224 log.trace("updated dictionary count " SIZE_FORMAT " %s", chunk_manager()->humongous_dictionary()->total_count(), chunk_size_name(HumongousIndex));
2225 chunk_manager()->slow_locked_verify();
2226 }
2227
2228 const char* SpaceManager::chunk_size_name(ChunkIndex index) const {
2229 switch (index) {
2230 case SpecializedIndex:
2231 return "Specialized";
2232 case SmallIndex:
2233 return "Small";
2234 case MediumIndex:
2235 return "Medium";
2236 case HumongousIndex:
2237 return "Humongous";
2238 default:
2239 return NULL;
2240 }
2241 }
2242
2243 ChunkIndex ChunkManager::list_index(size_t size) {
2244 switch (size) {
2245 case SpecializedChunk:
2246 assert(SpecializedChunk == ClassSpecializedChunk,
2247 "Need branch for ClassSpecializedChunk");
2248 return SpecializedIndex;
2249 case SmallChunk:
2250 case ClassSmallChunk:
2251 return SmallIndex;
2252 case MediumChunk:
2253 case ClassMediumChunk:
2254 return MediumIndex;
2255 default:
2256 assert(size > MediumChunk || size > ClassMediumChunk,
2257 "Not a humongous chunk");
2258 return HumongousIndex;
2259 }
2260 }
2261
2262 void SpaceManager::deallocate(MetaWord* p, size_t word_size) {
2263 assert_lock_strong(_lock);
2264 size_t raw_word_size = get_raw_word_size(word_size);
2265 size_t min_size = TreeChunk<Metablock, FreeList<Metablock> >::min_size();
2266 assert(raw_word_size >= min_size,
2267 "Should not deallocate dark matter " SIZE_FORMAT "<" SIZE_FORMAT, word_size, min_size);
2268 block_freelists()->return_block(p, raw_word_size);
2269 }
2270
2271 // Adds a chunk to the list of chunks in use.
2272 void SpaceManager::add_chunk(Metachunk* new_chunk, bool make_current) {
2273
2274 assert(new_chunk != NULL, "Should not be NULL");
2275 assert(new_chunk->next() == NULL, "Should not be on a list");
2276
2277 new_chunk->reset_empty();
2278
2279 // Find the correct list and and set the current
2280 // chunk for that list.
2281 ChunkIndex index = ChunkManager::list_index(new_chunk->word_size());
2282
2283 if (index != HumongousIndex) {
2284 retire_current_chunk();
2285 set_current_chunk(new_chunk);
2286 new_chunk->set_next(chunks_in_use(index));
2287 set_chunks_in_use(index, new_chunk);
2288 } else {
2289 // For null class loader data and DumpSharedSpaces, the first chunk isn't
2290 // small, so small will be null. Link this first chunk as the current
2291 // chunk.
2292 if (make_current) {
2293 // Set as the current chunk but otherwise treat as a humongous chunk.
2294 set_current_chunk(new_chunk);
2295 }
2296 // Link at head. The _current_chunk only points to a humongous chunk for
2297 // the null class loader metaspace (class and data virtual space managers)
2298 // any humongous chunks so will not point to the tail
2299 // of the humongous chunks list.
2300 new_chunk->set_next(chunks_in_use(HumongousIndex));
2301 set_chunks_in_use(HumongousIndex, new_chunk);
2302
2303 assert(new_chunk->word_size() > medium_chunk_size(), "List inconsistency");
2304 }
2305
2306 // Add to the running sum of capacity
2307 inc_size_metrics(new_chunk->word_size());
2308
2309 assert(new_chunk->is_empty(), "Not ready for reuse");
2310 LogHandle(gc, metaspace, freelist) log;
2311 if (log.is_trace()) {
2312 log.trace("SpaceManager::add_chunk: " SIZE_FORMAT ") ", sum_count_in_chunks_in_use());
2313 ResourceMark rm;
2314 outputStream* out = log.trace_stream();
2315 new_chunk->print_on(out);
2316 chunk_manager()->locked_print_free_chunks(out);
2317 }
2318 }
2319
2320 void SpaceManager::retire_current_chunk() {
2321 if (current_chunk() != NULL) {
2322 size_t remaining_words = current_chunk()->free_word_size();
2323 if (remaining_words >= TreeChunk<Metablock, FreeList<Metablock> >::min_size()) {
2324 block_freelists()->return_block(current_chunk()->allocate(remaining_words), remaining_words);
2325 inc_used_metrics(remaining_words);
2326 }
2327 }
2328 }
2329
2330 Metachunk* SpaceManager::get_new_chunk(size_t word_size,
2331 size_t grow_chunks_by_words) {
2332 // Get a chunk from the chunk freelist
2333 Metachunk* next = chunk_manager()->chunk_freelist_allocate(grow_chunks_by_words);
2334
2335 if (next == NULL) {
2336 next = vs_list()->get_new_chunk(word_size,
2337 grow_chunks_by_words,
2338 medium_chunk_bunch());
2339 }
2340
2341 LogHandle(gc, metaspace, alloc) log;
2342 if (log.is_debug() && next != NULL &&
2343 SpaceManager::is_humongous(next->word_size())) {
2344 log.debug(" new humongous chunk word size " PTR_FORMAT, next->word_size());
2345 }
2346
2347 return next;
2348 }
2349
2350 /*
2351 * The policy is to allocate up to _small_chunk_limit small chunks
2352 * after which only medium chunks are allocated. This is done to
2353 * reduce fragmentation. In some cases, this can result in a lot
2354 * of small chunks being allocated to the point where it's not
2355 * possible to expand. If this happens, there may be no medium chunks
2356 * available and OOME would be thrown. Instead of doing that,
2357 * if the allocation request size fits in a small chunk, an attempt
2358 * will be made to allocate a small chunk.
2359 */
2360 MetaWord* SpaceManager::get_small_chunk_and_allocate(size_t word_size) {
2361 size_t raw_word_size = get_raw_word_size(word_size);
2362
2363 if (raw_word_size + Metachunk::overhead() > small_chunk_size()) {
2364 return NULL;
2365 }
2366
2367 MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag);
2368 MutexLockerEx cl1(expand_lock(), Mutex::_no_safepoint_check_flag);
2369
2370 Metachunk* chunk = chunk_manager()->chunk_freelist_allocate(small_chunk_size());
2371
2372 MetaWord* mem = NULL;
2373
2374 if (chunk != NULL) {
2375 // Add chunk to the in-use chunk list and do an allocation from it.
2376 // Add to this manager's list of chunks in use.
2377 add_chunk(chunk, false);
2378 mem = chunk->allocate(raw_word_size);
2379
2380 inc_used_metrics(raw_word_size);
2381
2382 // Track metaspace memory usage statistic.
2383 track_metaspace_memory_usage();
2384 }
2385
2386 return mem;
2387 }
2388
2389 MetaWord* SpaceManager::allocate(size_t word_size) {
2390 MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag);
2391
2392 size_t raw_word_size = get_raw_word_size(word_size);
2393 BlockFreelist* fl = block_freelists();
2394 MetaWord* p = NULL;
2395 // Allocation from the dictionary is expensive in the sense that
2396 // the dictionary has to be searched for a size. Don't allocate
2397 // from the dictionary until it starts to get fat. Is this
2398 // a reasonable policy? Maybe an skinny dictionary is fast enough
2399 // for allocations. Do some profiling. JJJ
2400 if (fl->total_size() > allocation_from_dictionary_limit) {
2401 p = fl->get_block(raw_word_size);
2402 }
2403 if (p == NULL) {
2404 p = allocate_work(raw_word_size);
2405 }
2406
2407 return p;
2408 }
2409
2410 // Returns the address of spaced allocated for "word_size".
2411 // This methods does not know about blocks (Metablocks)
2412 MetaWord* SpaceManager::allocate_work(size_t word_size) {
2413 assert_lock_strong(_lock);
2414 #ifdef ASSERT
2415 if (Metadebug::test_metadata_failure()) {
2416 return NULL;
2417 }
2418 #endif
2419 // Is there space in the current chunk?
2420 MetaWord* result = NULL;
2421
2422 // For DumpSharedSpaces, only allocate out of the current chunk which is
2423 // never null because we gave it the size we wanted. Caller reports out
2424 // of memory if this returns null.
2425 if (DumpSharedSpaces) {
2426 assert(current_chunk() != NULL, "should never happen");
2427 inc_used_metrics(word_size);
2428 return current_chunk()->allocate(word_size); // caller handles null result
2429 }
2430
2431 if (current_chunk() != NULL) {
2432 result = current_chunk()->allocate(word_size);
2433 }
2434
2435 if (result == NULL) {
2436 result = grow_and_allocate(word_size);
2437 }
2438
2439 if (result != NULL) {
2440 inc_used_metrics(word_size);
2441 assert(result != (MetaWord*) chunks_in_use(MediumIndex),
2442 "Head of the list is being allocated");
2443 }
2444
2445 return result;
2446 }
2447
2448 void SpaceManager::verify() {
2449 // If there are blocks in the dictionary, then
2450 // verification of chunks does not work since
2451 // being in the dictionary alters a chunk.
2452 if (block_freelists()->total_size() == 0) {
2453 for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) {
2454 Metachunk* curr = chunks_in_use(i);
2455 while (curr != NULL) {
2456 curr->verify();
2457 verify_chunk_size(curr);
2458 curr = curr->next();
2459 }
2460 }
2461 }
2462 }
2463
2464 void SpaceManager::verify_chunk_size(Metachunk* chunk) {
2465 assert(is_humongous(chunk->word_size()) ||
2466 chunk->word_size() == medium_chunk_size() ||
2467 chunk->word_size() == small_chunk_size() ||
2468 chunk->word_size() == specialized_chunk_size(),
2469 "Chunk size is wrong");
2470 return;
2471 }
2472
2473 #ifdef ASSERT
2474 void SpaceManager::verify_allocated_blocks_words() {
2475 // Verification is only guaranteed at a safepoint.
2476 assert(SafepointSynchronize::is_at_safepoint() || !Universe::is_fully_initialized(),
2477 "Verification can fail if the applications is running");
2478 assert(allocated_blocks_words() == sum_used_in_chunks_in_use(),
2479 "allocation total is not consistent " SIZE_FORMAT
2480 " vs " SIZE_FORMAT,
2481 allocated_blocks_words(), sum_used_in_chunks_in_use());
2482 }
2483
2484 #endif
2485
2486 void SpaceManager::dump(outputStream* const out) const {
2487 size_t curr_total = 0;
2488 size_t waste = 0;
2489 uint i = 0;
2490 size_t used = 0;
2491 size_t capacity = 0;
2492
2493 // Add up statistics for all chunks in this SpaceManager.
2494 for (ChunkIndex index = ZeroIndex;
2495 index < NumberOfInUseLists;
2496 index = next_chunk_index(index)) {
2497 for (Metachunk* curr = chunks_in_use(index);
2498 curr != NULL;
2499 curr = curr->next()) {
2500 out->print("%d) ", i++);
2501 curr->print_on(out);
2502 curr_total += curr->word_size();
2503 used += curr->used_word_size();
2504 capacity += curr->word_size();
2505 waste += curr->free_word_size() + curr->overhead();;
2506 }
2507 }
2508
2509 if (log_is_enabled(Trace, gc, metaspace, freelist)) {
2510 block_freelists()->print_on(out);
2511 }
2512
2513 size_t free = current_chunk() == NULL ? 0 : current_chunk()->free_word_size();
2514 // Free space isn't wasted.
2515 waste -= free;
2516
2517 out->print_cr("total of all chunks " SIZE_FORMAT " used " SIZE_FORMAT
2518 " free " SIZE_FORMAT " capacity " SIZE_FORMAT
2519 " waste " SIZE_FORMAT, curr_total, used, free, capacity, waste);
2520 }
2521
2522 #ifndef PRODUCT
2523 void SpaceManager::mangle_freed_chunks() {
2524 for (ChunkIndex index = ZeroIndex;
2525 index < NumberOfInUseLists;
2526 index = next_chunk_index(index)) {
2527 for (Metachunk* curr = chunks_in_use(index);
2528 curr != NULL;
2529 curr = curr->next()) {
2530 curr->mangle();
2531 }
2532 }
2533 }
2534 #endif // PRODUCT
2535
2536 // MetaspaceAux
2537
2538
2539 size_t MetaspaceAux::_capacity_words[] = {0, 0};
2540 size_t MetaspaceAux::_used_words[] = {0, 0};
2541
2542 size_t MetaspaceAux::free_bytes(Metaspace::MetadataType mdtype) {
2543 VirtualSpaceList* list = Metaspace::get_space_list(mdtype);
2544 return list == NULL ? 0 : list->free_bytes();
2545 }
2546
2547 size_t MetaspaceAux::free_bytes() {
2548 return free_bytes(Metaspace::ClassType) + free_bytes(Metaspace::NonClassType);
2549 }
2550
2551 void MetaspaceAux::dec_capacity(Metaspace::MetadataType mdtype, size_t words) {
2552 assert_lock_strong(SpaceManager::expand_lock());
2553 assert(words <= capacity_words(mdtype),
2554 "About to decrement below 0: words " SIZE_FORMAT
2555 " is greater than _capacity_words[%u] " SIZE_FORMAT,
2556 words, mdtype, capacity_words(mdtype));
2557 _capacity_words[mdtype] -= words;
2558 }
2559
2560 void MetaspaceAux::inc_capacity(Metaspace::MetadataType mdtype, size_t words) {
2561 assert_lock_strong(SpaceManager::expand_lock());
2562 // Needs to be atomic
2563 _capacity_words[mdtype] += words;
2564 }
2565
2566 void MetaspaceAux::dec_used(Metaspace::MetadataType mdtype, size_t words) {
2567 assert(words <= used_words(mdtype),
2568 "About to decrement below 0: words " SIZE_FORMAT
2569 " is greater than _used_words[%u] " SIZE_FORMAT,
2570 words, mdtype, used_words(mdtype));
2571 // For CMS deallocation of the Metaspaces occurs during the
2572 // sweep which is a concurrent phase. Protection by the expand_lock()
2573 // is not enough since allocation is on a per Metaspace basis
2574 // and protected by the Metaspace lock.
2575 jlong minus_words = (jlong) - (jlong) words;
2576 Atomic::add_ptr(minus_words, &_used_words[mdtype]);
2577 }
2578
2579 void MetaspaceAux::inc_used(Metaspace::MetadataType mdtype, size_t words) {
2580 // _used_words tracks allocations for
2581 // each piece of metadata. Those allocations are
2582 // generally done concurrently by different application
2583 // threads so must be done atomically.
2584 Atomic::add_ptr(words, &_used_words[mdtype]);
2585 }
2586
2587 size_t MetaspaceAux::used_bytes_slow(Metaspace::MetadataType mdtype) {
2588 size_t used = 0;
2589 ClassLoaderDataGraphMetaspaceIterator iter;
2590 while (iter.repeat()) {
2591 Metaspace* msp = iter.get_next();
2592 // Sum allocated_blocks_words for each metaspace
2593 if (msp != NULL) {
2594 used += msp->used_words_slow(mdtype);
2595 }
2596 }
2597 return used * BytesPerWord;
2598 }
2599
2600 size_t MetaspaceAux::free_bytes_slow(Metaspace::MetadataType mdtype) {
2601 size_t free = 0;
2602 ClassLoaderDataGraphMetaspaceIterator iter;
2603 while (iter.repeat()) {
2604 Metaspace* msp = iter.get_next();
2605 if (msp != NULL) {
2606 free += msp->free_words_slow(mdtype);
2607 }
2608 }
2609 return free * BytesPerWord;
2610 }
2611
2612 size_t MetaspaceAux::capacity_bytes_slow(Metaspace::MetadataType mdtype) {
2613 if ((mdtype == Metaspace::ClassType) && !Metaspace::using_class_space()) {
2614 return 0;
2615 }
2616 // Don't count the space in the freelists. That space will be
2617 // added to the capacity calculation as needed.
2618 size_t capacity = 0;
2619 ClassLoaderDataGraphMetaspaceIterator iter;
2620 while (iter.repeat()) {
2621 Metaspace* msp = iter.get_next();
2622 if (msp != NULL) {
2623 capacity += msp->capacity_words_slow(mdtype);
2624 }
2625 }
2626 return capacity * BytesPerWord;
2627 }
2628
2629 size_t MetaspaceAux::capacity_bytes_slow() {
2630 #ifdef PRODUCT
2631 // Use capacity_bytes() in PRODUCT instead of this function.
2632 guarantee(false, "Should not call capacity_bytes_slow() in the PRODUCT");
2633 #endif
2634 size_t class_capacity = capacity_bytes_slow(Metaspace::ClassType);
2635 size_t non_class_capacity = capacity_bytes_slow(Metaspace::NonClassType);
2636 assert(capacity_bytes() == class_capacity + non_class_capacity,
2637 "bad accounting: capacity_bytes() " SIZE_FORMAT
2638 " class_capacity + non_class_capacity " SIZE_FORMAT
2639 " class_capacity " SIZE_FORMAT " non_class_capacity " SIZE_FORMAT,
2640 capacity_bytes(), class_capacity + non_class_capacity,
2641 class_capacity, non_class_capacity);
2642
2643 return class_capacity + non_class_capacity;
2644 }
2645
2646 size_t MetaspaceAux::reserved_bytes(Metaspace::MetadataType mdtype) {
2647 VirtualSpaceList* list = Metaspace::get_space_list(mdtype);
2648 return list == NULL ? 0 : list->reserved_bytes();
2649 }
2650
2651 size_t MetaspaceAux::committed_bytes(Metaspace::MetadataType mdtype) {
2652 VirtualSpaceList* list = Metaspace::get_space_list(mdtype);
2653 return list == NULL ? 0 : list->committed_bytes();
2654 }
2655
2656 size_t MetaspaceAux::min_chunk_size_words() { return Metaspace::first_chunk_word_size(); }
2657
2658 size_t MetaspaceAux::free_chunks_total_words(Metaspace::MetadataType mdtype) {
2659 ChunkManager* chunk_manager = Metaspace::get_chunk_manager(mdtype);
2660 if (chunk_manager == NULL) {
2661 return 0;
2662 }
2663 chunk_manager->slow_verify();
2664 return chunk_manager->free_chunks_total_words();
2665 }
2666
2667 size_t MetaspaceAux::free_chunks_total_bytes(Metaspace::MetadataType mdtype) {
2668 return free_chunks_total_words(mdtype) * BytesPerWord;
2669 }
2670
2671 size_t MetaspaceAux::free_chunks_total_words() {
2672 return free_chunks_total_words(Metaspace::ClassType) +
2673 free_chunks_total_words(Metaspace::NonClassType);
2674 }
2675
2676 size_t MetaspaceAux::free_chunks_total_bytes() {
2677 return free_chunks_total_words() * BytesPerWord;
2678 }
2679
2680 bool MetaspaceAux::has_chunk_free_list(Metaspace::MetadataType mdtype) {
2681 return Metaspace::get_chunk_manager(mdtype) != NULL;
2682 }
2683
2684 MetaspaceChunkFreeListSummary MetaspaceAux::chunk_free_list_summary(Metaspace::MetadataType mdtype) {
2685 if (!has_chunk_free_list(mdtype)) {
2686 return MetaspaceChunkFreeListSummary();
2687 }
2688
2689 const ChunkManager* cm = Metaspace::get_chunk_manager(mdtype);
2690 return cm->chunk_free_list_summary();
2691 }
2692
2693 void MetaspaceAux::print_metaspace_change(size_t prev_metadata_used) {
2694 log_info(gc, metaspace)("Metaspace: " SIZE_FORMAT "K->" SIZE_FORMAT "K(" SIZE_FORMAT "K)",
2695 prev_metadata_used/K, used_bytes()/K, reserved_bytes()/K);
2696 }
2697
2698 void MetaspaceAux::print_on(outputStream* out) {
2699 Metaspace::MetadataType nct = Metaspace::NonClassType;
2700
2701 out->print_cr(" Metaspace "
2702 "used " SIZE_FORMAT "K, "
2703 "capacity " SIZE_FORMAT "K, "
2704 "committed " SIZE_FORMAT "K, "
2705 "reserved " SIZE_FORMAT "K",
2706 used_bytes()/K,
2707 capacity_bytes()/K,
2708 committed_bytes()/K,
2709 reserved_bytes()/K);
2710
2711 if (Metaspace::using_class_space()) {
2712 Metaspace::MetadataType ct = Metaspace::ClassType;
2713 out->print_cr(" class space "
2714 "used " SIZE_FORMAT "K, "
2715 "capacity " SIZE_FORMAT "K, "
2716 "committed " SIZE_FORMAT "K, "
2717 "reserved " SIZE_FORMAT "K",
2718 used_bytes(ct)/K,
2719 capacity_bytes(ct)/K,
2720 committed_bytes(ct)/K,
2721 reserved_bytes(ct)/K);
2722 }
2723 }
2724
2725 // Print information for class space and data space separately.
2726 // This is almost the same as above.
2727 void MetaspaceAux::print_on(outputStream* out, Metaspace::MetadataType mdtype) {
2728 size_t free_chunks_capacity_bytes = free_chunks_total_bytes(mdtype);
2729 size_t capacity_bytes = capacity_bytes_slow(mdtype);
2730 size_t used_bytes = used_bytes_slow(mdtype);
2731 size_t free_bytes = free_bytes_slow(mdtype);
2732 size_t used_and_free = used_bytes + free_bytes +
2733 free_chunks_capacity_bytes;
2734 out->print_cr(" Chunk accounting: used in chunks " SIZE_FORMAT
2735 "K + unused in chunks " SIZE_FORMAT "K + "
2736 " capacity in free chunks " SIZE_FORMAT "K = " SIZE_FORMAT
2737 "K capacity in allocated chunks " SIZE_FORMAT "K",
2738 used_bytes / K,
2739 free_bytes / K,
2740 free_chunks_capacity_bytes / K,
2741 used_and_free / K,
2742 capacity_bytes / K);
2743 // Accounting can only be correct if we got the values during a safepoint
2744 assert(!SafepointSynchronize::is_at_safepoint() || used_and_free == capacity_bytes, "Accounting is wrong");
2745 }
2746
2747 // Print total fragmentation for class metaspaces
2748 void MetaspaceAux::print_class_waste(outputStream* out) {
2749 assert(Metaspace::using_class_space(), "class metaspace not used");
2750 size_t cls_specialized_waste = 0, cls_small_waste = 0, cls_medium_waste = 0;
2751 size_t cls_specialized_count = 0, cls_small_count = 0, cls_medium_count = 0, cls_humongous_count = 0;
2752 ClassLoaderDataGraphMetaspaceIterator iter;
2753 while (iter.repeat()) {
2754 Metaspace* msp = iter.get_next();
2755 if (msp != NULL) {
2756 cls_specialized_waste += msp->class_vsm()->sum_waste_in_chunks_in_use(SpecializedIndex);
2757 cls_specialized_count += msp->class_vsm()->sum_count_in_chunks_in_use(SpecializedIndex);
2758 cls_small_waste += msp->class_vsm()->sum_waste_in_chunks_in_use(SmallIndex);
2759 cls_small_count += msp->class_vsm()->sum_count_in_chunks_in_use(SmallIndex);
2760 cls_medium_waste += msp->class_vsm()->sum_waste_in_chunks_in_use(MediumIndex);
2761 cls_medium_count += msp->class_vsm()->sum_count_in_chunks_in_use(MediumIndex);
2762 cls_humongous_count += msp->class_vsm()->sum_count_in_chunks_in_use(HumongousIndex);
2763 }
2764 }
2765 out->print_cr(" class: " SIZE_FORMAT " specialized(s) " SIZE_FORMAT ", "
2766 SIZE_FORMAT " small(s) " SIZE_FORMAT ", "
2767 SIZE_FORMAT " medium(s) " SIZE_FORMAT ", "
2768 "large count " SIZE_FORMAT,
2769 cls_specialized_count, cls_specialized_waste,
2770 cls_small_count, cls_small_waste,
2771 cls_medium_count, cls_medium_waste, cls_humongous_count);
2772 }
2773
2774 // Print total fragmentation for data and class metaspaces separately
2775 void MetaspaceAux::print_waste(outputStream* out) {
2776 size_t specialized_waste = 0, small_waste = 0, medium_waste = 0;
2777 size_t specialized_count = 0, small_count = 0, medium_count = 0, humongous_count = 0;
2778
2779 ClassLoaderDataGraphMetaspaceIterator iter;
2780 while (iter.repeat()) {
2781 Metaspace* msp = iter.get_next();
2782 if (msp != NULL) {
2783 specialized_waste += msp->vsm()->sum_waste_in_chunks_in_use(SpecializedIndex);
2784 specialized_count += msp->vsm()->sum_count_in_chunks_in_use(SpecializedIndex);
2785 small_waste += msp->vsm()->sum_waste_in_chunks_in_use(SmallIndex);
2786 small_count += msp->vsm()->sum_count_in_chunks_in_use(SmallIndex);
2787 medium_waste += msp->vsm()->sum_waste_in_chunks_in_use(MediumIndex);
2788 medium_count += msp->vsm()->sum_count_in_chunks_in_use(MediumIndex);
2789 humongous_count += msp->vsm()->sum_count_in_chunks_in_use(HumongousIndex);
2790 }
2791 }
2792 out->print_cr("Total fragmentation waste (words) doesn't count free space");
2793 out->print_cr(" data: " SIZE_FORMAT " specialized(s) " SIZE_FORMAT ", "
2794 SIZE_FORMAT " small(s) " SIZE_FORMAT ", "
2795 SIZE_FORMAT " medium(s) " SIZE_FORMAT ", "
2796 "large count " SIZE_FORMAT,
2797 specialized_count, specialized_waste, small_count,
2798 small_waste, medium_count, medium_waste, humongous_count);
2799 if (Metaspace::using_class_space()) {
2800 print_class_waste(out);
2801 }
2802 }
2803
2804 // Dump global metaspace things from the end of ClassLoaderDataGraph
2805 void MetaspaceAux::dump(outputStream* out) {
2806 out->print_cr("All Metaspace:");
2807 out->print("data space: "); print_on(out, Metaspace::NonClassType);
2808 out->print("class space: "); print_on(out, Metaspace::ClassType);
2809 print_waste(out);
2810 }
2811
2812 void MetaspaceAux::verify_free_chunks() {
2813 Metaspace::chunk_manager_metadata()->verify();
2814 if (Metaspace::using_class_space()) {
2815 Metaspace::chunk_manager_class()->verify();
2816 }
2817 }
2818
2819 void MetaspaceAux::verify_capacity() {
2820 #ifdef ASSERT
2821 size_t running_sum_capacity_bytes = capacity_bytes();
2822 // For purposes of the running sum of capacity, verify against capacity
2823 size_t capacity_in_use_bytes = capacity_bytes_slow();
2824 assert(running_sum_capacity_bytes == capacity_in_use_bytes,
2825 "capacity_words() * BytesPerWord " SIZE_FORMAT
2826 " capacity_bytes_slow()" SIZE_FORMAT,
2827 running_sum_capacity_bytes, capacity_in_use_bytes);
2828 for (Metaspace::MetadataType i = Metaspace::ClassType;
2829 i < Metaspace:: MetadataTypeCount;
2830 i = (Metaspace::MetadataType)(i + 1)) {
2831 size_t capacity_in_use_bytes = capacity_bytes_slow(i);
2832 assert(capacity_bytes(i) == capacity_in_use_bytes,
2833 "capacity_bytes(%u) " SIZE_FORMAT
2834 " capacity_bytes_slow(%u)" SIZE_FORMAT,
2835 i, capacity_bytes(i), i, capacity_in_use_bytes);
2836 }
2837 #endif
2838 }
2839
2840 void MetaspaceAux::verify_used() {
2841 #ifdef ASSERT
2842 size_t running_sum_used_bytes = used_bytes();
2843 // For purposes of the running sum of used, verify against used
2844 size_t used_in_use_bytes = used_bytes_slow();
2845 assert(used_bytes() == used_in_use_bytes,
2846 "used_bytes() " SIZE_FORMAT
2847 " used_bytes_slow()" SIZE_FORMAT,
2848 used_bytes(), used_in_use_bytes);
2849 for (Metaspace::MetadataType i = Metaspace::ClassType;
2850 i < Metaspace:: MetadataTypeCount;
2851 i = (Metaspace::MetadataType)(i + 1)) {
2852 size_t used_in_use_bytes = used_bytes_slow(i);
2853 assert(used_bytes(i) == used_in_use_bytes,
2854 "used_bytes(%u) " SIZE_FORMAT
2855 " used_bytes_slow(%u)" SIZE_FORMAT,
2856 i, used_bytes(i), i, used_in_use_bytes);
2857 }
2858 #endif
2859 }
2860
2861 void MetaspaceAux::verify_metrics() {
2862 verify_capacity();
2863 verify_used();
2864 }
2865
2866
2867 // Metaspace methods
2868
2869 size_t Metaspace::_first_chunk_word_size = 0;
2870 size_t Metaspace::_first_class_chunk_word_size = 0;
2871
2872 size_t Metaspace::_commit_alignment = 0;
2873 size_t Metaspace::_reserve_alignment = 0;
2874
2875 Metaspace::Metaspace(Mutex* lock, MetaspaceType type) {
2876 initialize(lock, type);
2877 }
2878
2879 Metaspace::~Metaspace() {
2880 delete _vsm;
2881 if (using_class_space()) {
2882 delete _class_vsm;
2883 }
2884 }
2885
2886 VirtualSpaceList* Metaspace::_space_list = NULL;
2887 VirtualSpaceList* Metaspace::_class_space_list = NULL;
2888
2889 ChunkManager* Metaspace::_chunk_manager_metadata = NULL;
2890 ChunkManager* Metaspace::_chunk_manager_class = NULL;
2891
2892 #define VIRTUALSPACEMULTIPLIER 2
2893
2894 #ifdef _LP64
2895 static const uint64_t UnscaledClassSpaceMax = (uint64_t(max_juint) + 1);
2896
2897 void Metaspace::set_narrow_klass_base_and_shift(address metaspace_base, address cds_base) {
2898 // Figure out the narrow_klass_base and the narrow_klass_shift. The
2899 // narrow_klass_base is the lower of the metaspace base and the cds base
2900 // (if cds is enabled). The narrow_klass_shift depends on the distance
2901 // between the lower base and higher address.
2902 address lower_base;
2903 address higher_address;
2904 #if INCLUDE_CDS
2905 if (UseSharedSpaces) {
2906 higher_address = MAX2((address)(cds_base + FileMapInfo::shared_spaces_size()),
2907 (address)(metaspace_base + compressed_class_space_size()));
2908 lower_base = MIN2(metaspace_base, cds_base);
2909 } else
2910 #endif
2911 {
2912 higher_address = metaspace_base + compressed_class_space_size();
2913 lower_base = metaspace_base;
2914
2915 uint64_t klass_encoding_max = UnscaledClassSpaceMax << LogKlassAlignmentInBytes;
2916 // If compressed class space fits in lower 32G, we don't need a base.
2917 if (higher_address <= (address)klass_encoding_max) {
2918 lower_base = 0; // Effectively lower base is zero.
2919 }
2920 }
2921
2922 Universe::set_narrow_klass_base(lower_base);
2923
2924 if ((uint64_t)(higher_address - lower_base) <= UnscaledClassSpaceMax) {
2925 Universe::set_narrow_klass_shift(0);
2926 } else {
2927 assert(!UseSharedSpaces, "Cannot shift with UseSharedSpaces");
2928 Universe::set_narrow_klass_shift(LogKlassAlignmentInBytes);
2929 }
2930 }
2931
2932 #if INCLUDE_CDS
2933 // Return TRUE if the specified metaspace_base and cds_base are close enough
2934 // to work with compressed klass pointers.
2935 bool Metaspace::can_use_cds_with_metaspace_addr(char* metaspace_base, address cds_base) {
2936 assert(cds_base != 0 && UseSharedSpaces, "Only use with CDS");
2937 assert(UseCompressedClassPointers, "Only use with CompressedKlassPtrs");
2938 address lower_base = MIN2((address)metaspace_base, cds_base);
2939 address higher_address = MAX2((address)(cds_base + FileMapInfo::shared_spaces_size()),
2940 (address)(metaspace_base + compressed_class_space_size()));
2941 return ((uint64_t)(higher_address - lower_base) <= UnscaledClassSpaceMax);
2942 }
2943 #endif
2944
2945 // Try to allocate the metaspace at the requested addr.
2946 void Metaspace::allocate_metaspace_compressed_klass_ptrs(char* requested_addr, address cds_base) {
2947 assert(using_class_space(), "called improperly");
2948 assert(UseCompressedClassPointers, "Only use with CompressedKlassPtrs");
2949 assert(compressed_class_space_size() < KlassEncodingMetaspaceMax,
2950 "Metaspace size is too big");
2951 assert_is_ptr_aligned(requested_addr, _reserve_alignment);
2952 assert_is_ptr_aligned(cds_base, _reserve_alignment);
2953 assert_is_size_aligned(compressed_class_space_size(), _reserve_alignment);
2954
2955 // Don't use large pages for the class space.
2956 bool large_pages = false;
2957
2958 #ifndef AARCH64
2959 ReservedSpace metaspace_rs = ReservedSpace(compressed_class_space_size(),
2960 _reserve_alignment,
2961 large_pages,
2962 requested_addr);
2963 #else // AARCH64
2964 ReservedSpace metaspace_rs;
2965
2966 // Our compressed klass pointers may fit nicely into the lower 32
2967 // bits.
2968 if ((uint64_t)requested_addr + compressed_class_space_size() < 4*G) {
2969 metaspace_rs = ReservedSpace(compressed_class_space_size(),
2970 _reserve_alignment,
2971 large_pages,
2972 requested_addr);
2973 }
2974
2975 if (! metaspace_rs.is_reserved()) {
2976 // Try to align metaspace so that we can decode a compressed klass
2977 // with a single MOVK instruction. We can do this iff the
2978 // compressed class base is a multiple of 4G.
2979 for (char *a = (char*)align_ptr_up(requested_addr, 4*G);
2980 a < (char*)(1024*G);
2981 a += 4*G) {
2982
2983 #if INCLUDE_CDS
2984 if (UseSharedSpaces
2985 && ! can_use_cds_with_metaspace_addr(a, cds_base)) {
2986 // We failed to find an aligned base that will reach. Fall
2987 // back to using our requested addr.
2988 metaspace_rs = ReservedSpace(compressed_class_space_size(),
2989 _reserve_alignment,
2990 large_pages,
2991 requested_addr);
2992 break;
2993 }
2994 #endif
2995
2996 metaspace_rs = ReservedSpace(compressed_class_space_size(),
2997 _reserve_alignment,
2998 large_pages,
2999 a);
3000 if (metaspace_rs.is_reserved())
3001 break;
3002 }
3003 }
3004
3005 #endif // AARCH64
3006
3007 if (!metaspace_rs.is_reserved()) {
3008 #if INCLUDE_CDS
3009 if (UseSharedSpaces) {
3010 size_t increment = align_size_up(1*G, _reserve_alignment);
3011
3012 // Keep trying to allocate the metaspace, increasing the requested_addr
3013 // by 1GB each time, until we reach an address that will no longer allow
3014 // use of CDS with compressed klass pointers.
3015 char *addr = requested_addr;
3016 while (!metaspace_rs.is_reserved() && (addr + increment > addr) &&
3017 can_use_cds_with_metaspace_addr(addr + increment, cds_base)) {
3018 addr = addr + increment;
3019 metaspace_rs = ReservedSpace(compressed_class_space_size(),
3020 _reserve_alignment, large_pages, addr);
3021 }
3022 }
3023 #endif
3024 // If no successful allocation then try to allocate the space anywhere. If
3025 // that fails then OOM doom. At this point we cannot try allocating the
3026 // metaspace as if UseCompressedClassPointers is off because too much
3027 // initialization has happened that depends on UseCompressedClassPointers.
3028 // So, UseCompressedClassPointers cannot be turned off at this point.
3029 if (!metaspace_rs.is_reserved()) {
3030 metaspace_rs = ReservedSpace(compressed_class_space_size(),
3031 _reserve_alignment, large_pages);
3032 if (!metaspace_rs.is_reserved()) {
3033 vm_exit_during_initialization(err_msg("Could not allocate metaspace: " SIZE_FORMAT " bytes",
3034 compressed_class_space_size()));
3035 }
3036 }
3037 }
3038
3039 // If we got here then the metaspace got allocated.
3040 MemTracker::record_virtual_memory_type((address)metaspace_rs.base(), mtClass);
3041
3042 #if INCLUDE_CDS
3043 // Verify that we can use shared spaces. Otherwise, turn off CDS.
3044 if (UseSharedSpaces && !can_use_cds_with_metaspace_addr(metaspace_rs.base(), cds_base)) {
3045 FileMapInfo::stop_sharing_and_unmap(
3046 "Could not allocate metaspace at a compatible address");
3047 }
3048 #endif
3049 set_narrow_klass_base_and_shift((address)metaspace_rs.base(),
3050 UseSharedSpaces ? (address)cds_base : 0);
3051
3052 initialize_class_space(metaspace_rs);
3053
3054 if (develop_log_is_enabled(Trace, gc, metaspace)) {
3055 LogHandle(gc, metaspace) log;
3056 ResourceMark rm;
3057 print_compressed_class_space(log.trace_stream(), requested_addr);
3058 }
3059 }
3060
3061 void Metaspace::print_compressed_class_space(outputStream* st, const char* requested_addr) {
3062 st->print_cr("Narrow klass base: " PTR_FORMAT ", Narrow klass shift: %d",
3063 p2i(Universe::narrow_klass_base()), Universe::narrow_klass_shift());
3064 if (_class_space_list != NULL) {
3065 address base = (address)_class_space_list->current_virtual_space()->bottom();
3066 st->print("Compressed class space size: " SIZE_FORMAT " Address: " PTR_FORMAT,
3067 compressed_class_space_size(), p2i(base));
3068 if (requested_addr != 0) {
3069 st->print(" Req Addr: " PTR_FORMAT, p2i(requested_addr));
3070 }
3071 st->cr();
3072 }
3073 }
3074
3075 // For UseCompressedClassPointers the class space is reserved above the top of
3076 // the Java heap. The argument passed in is at the base of the compressed space.
3077 void Metaspace::initialize_class_space(ReservedSpace rs) {
3078 // The reserved space size may be bigger because of alignment, esp with UseLargePages
3079 assert(rs.size() >= CompressedClassSpaceSize,
3080 SIZE_FORMAT " != " SIZE_FORMAT, rs.size(), CompressedClassSpaceSize);
3081 assert(using_class_space(), "Must be using class space");
3082 _class_space_list = new VirtualSpaceList(rs);
3083 _chunk_manager_class = new ChunkManager(SpecializedChunk, ClassSmallChunk, ClassMediumChunk);
3084
3085 if (!_class_space_list->initialization_succeeded()) {
3086 vm_exit_during_initialization("Failed to setup compressed class space virtual space list.");
3087 }
3088 }
3089
3090 #endif
3091
3092 void Metaspace::ergo_initialize() {
3093 if (DumpSharedSpaces) {
3094 // Using large pages when dumping the shared archive is currently not implemented.
3095 FLAG_SET_ERGO(bool, UseLargePagesInMetaspace, false);
3096 }
3097
3098 size_t page_size = os::vm_page_size();
3099 if (UseLargePages && UseLargePagesInMetaspace) {
3100 page_size = os::large_page_size();
3101 }
3102
3103 _commit_alignment = page_size;
3104 _reserve_alignment = MAX2(page_size, (size_t)os::vm_allocation_granularity());
3105
3106 // Do not use FLAG_SET_ERGO to update MaxMetaspaceSize, since this will
3107 // override if MaxMetaspaceSize was set on the command line or not.
3108 // This information is needed later to conform to the specification of the
3109 // java.lang.management.MemoryUsage API.
3110 //
3111 // Ideally, we would be able to set the default value of MaxMetaspaceSize in
3112 // globals.hpp to the aligned value, but this is not possible, since the
3113 // alignment depends on other flags being parsed.
3114 MaxMetaspaceSize = align_size_down_bounded(MaxMetaspaceSize, _reserve_alignment);
3115
3116 if (MetaspaceSize > MaxMetaspaceSize) {
3117 MetaspaceSize = MaxMetaspaceSize;
3118 }
3119
3120 MetaspaceSize = align_size_down_bounded(MetaspaceSize, _commit_alignment);
3121
3122 assert(MetaspaceSize <= MaxMetaspaceSize, "MetaspaceSize should be limited by MaxMetaspaceSize");
3123
3124 if (MetaspaceSize < 256*K) {
3125 vm_exit_during_initialization("Too small initial Metaspace size");
3126 }
3127
3128 MinMetaspaceExpansion = align_size_down_bounded(MinMetaspaceExpansion, _commit_alignment);
3129 MaxMetaspaceExpansion = align_size_down_bounded(MaxMetaspaceExpansion, _commit_alignment);
3130
3131 CompressedClassSpaceSize = align_size_down_bounded(CompressedClassSpaceSize, _reserve_alignment);
3132 set_compressed_class_space_size(CompressedClassSpaceSize);
3133 }
3134
3135 void Metaspace::global_initialize() {
3136 MetaspaceGC::initialize();
3137
3138 // Initialize the alignment for shared spaces.
3139 int max_alignment = os::vm_allocation_granularity();
3140 size_t cds_total = 0;
3141
3142 MetaspaceShared::set_max_alignment(max_alignment);
3143
3144 if (DumpSharedSpaces) {
3145 #if INCLUDE_CDS
3146 MetaspaceShared::estimate_regions_size();
3147
3148 SharedReadOnlySize = align_size_up(SharedReadOnlySize, max_alignment);
3149 SharedReadWriteSize = align_size_up(SharedReadWriteSize, max_alignment);
3150 SharedMiscDataSize = align_size_up(SharedMiscDataSize, max_alignment);
3151 SharedMiscCodeSize = align_size_up(SharedMiscCodeSize, max_alignment);
3152
3153 // Initialize with the sum of the shared space sizes. The read-only
3154 // and read write metaspace chunks will be allocated out of this and the
3155 // remainder is the misc code and data chunks.
3156 cds_total = FileMapInfo::shared_spaces_size();
3157 cds_total = align_size_up(cds_total, _reserve_alignment);
3158 _space_list = new VirtualSpaceList(cds_total/wordSize);
3159 _chunk_manager_metadata = new ChunkManager(SpecializedChunk, SmallChunk, MediumChunk);
3160
3161 if (!_space_list->initialization_succeeded()) {
3162 vm_exit_during_initialization("Unable to dump shared archive.", NULL);
3163 }
3164
3165 #ifdef _LP64
3166 if (cds_total + compressed_class_space_size() > UnscaledClassSpaceMax) {
3167 vm_exit_during_initialization("Unable to dump shared archive.",
3168 err_msg("Size of archive (" SIZE_FORMAT ") + compressed class space ("
3169 SIZE_FORMAT ") == total (" SIZE_FORMAT ") is larger than compressed "
3170 "klass limit: " UINT64_FORMAT, cds_total, compressed_class_space_size(),
3171 cds_total + compressed_class_space_size(), UnscaledClassSpaceMax));
3172 }
3173
3174 // Set the compressed klass pointer base so that decoding of these pointers works
3175 // properly when creating the shared archive.
3176 assert(UseCompressedOops && UseCompressedClassPointers,
3177 "UseCompressedOops and UseCompressedClassPointers must be set");
3178 Universe::set_narrow_klass_base((address)_space_list->current_virtual_space()->bottom());
3179 log_develop_trace(gc, metaspace)("Setting_narrow_klass_base to Address: " PTR_FORMAT,
3180 p2i(_space_list->current_virtual_space()->bottom()));
3181
3182 Universe::set_narrow_klass_shift(0);
3183 #endif // _LP64
3184 #endif // INCLUDE_CDS
3185 } else {
3186 // If using shared space, open the file that contains the shared space
3187 // and map in the memory before initializing the rest of metaspace (so
3188 // the addresses don't conflict)
3189 address cds_address = NULL;
3190 if (UseSharedSpaces) {
3191 #if INCLUDE_CDS
3192 FileMapInfo* mapinfo = new FileMapInfo();
3193
3194 // Open the shared archive file, read and validate the header. If
3195 // initialization fails, shared spaces [UseSharedSpaces] are
3196 // disabled and the file is closed.
3197 // Map in spaces now also
3198 if (mapinfo->initialize() && MetaspaceShared::map_shared_spaces(mapinfo)) {
3199 cds_total = FileMapInfo::shared_spaces_size();
3200 cds_address = (address)mapinfo->header()->region_addr(0);
3201 #ifdef _LP64
3202 if (using_class_space()) {
3203 char* cds_end = (char*)(cds_address + cds_total);
3204 cds_end = (char *)align_ptr_up(cds_end, _reserve_alignment);
3205 // If UseCompressedClassPointers is set then allocate the metaspace area
3206 // above the heap and above the CDS area (if it exists).
3207 allocate_metaspace_compressed_klass_ptrs(cds_end, cds_address);
3208 // Map the shared string space after compressed pointers
3209 // because it relies on compressed class pointers setting to work
3210 mapinfo->map_string_regions();
3211 }
3212 #endif // _LP64
3213 } else {
3214 assert(!mapinfo->is_open() && !UseSharedSpaces,
3215 "archive file not closed or shared spaces not disabled.");
3216 }
3217 #endif // INCLUDE_CDS
3218 }
3219
3220 #ifdef _LP64
3221 if (!UseSharedSpaces && using_class_space()) {
3222 char* base = (char*)align_ptr_up(Universe::heap()->reserved_region().end(), _reserve_alignment);
3223 allocate_metaspace_compressed_klass_ptrs(base, 0);
3224 }
3225 #endif // _LP64
3226
3227 // Initialize these before initializing the VirtualSpaceList
3228 _first_chunk_word_size = InitialBootClassLoaderMetaspaceSize / BytesPerWord;
3229 _first_chunk_word_size = align_word_size_up(_first_chunk_word_size);
3230 // Make the first class chunk bigger than a medium chunk so it's not put
3231 // on the medium chunk list. The next chunk will be small and progress
3232 // from there. This size calculated by -version.
3233 _first_class_chunk_word_size = MIN2((size_t)MediumChunk*6,
3234 (CompressedClassSpaceSize/BytesPerWord)*2);
3235 _first_class_chunk_word_size = align_word_size_up(_first_class_chunk_word_size);
3236 // Arbitrarily set the initial virtual space to a multiple
3237 // of the boot class loader size.
3238 size_t word_size = VIRTUALSPACEMULTIPLIER * _first_chunk_word_size;
3239 word_size = align_size_up(word_size, Metaspace::reserve_alignment_words());
3240
3241 // Initialize the list of virtual spaces.
3242 _space_list = new VirtualSpaceList(word_size);
3243 _chunk_manager_metadata = new ChunkManager(SpecializedChunk, SmallChunk, MediumChunk);
3244
3245 if (!_space_list->initialization_succeeded()) {
3246 vm_exit_during_initialization("Unable to setup metadata virtual space list.", NULL);
3247 }
3248 }
3249
3250 _tracer = new MetaspaceTracer();
3251 }
3252
3253 void Metaspace::post_initialize() {
3254 MetaspaceGC::post_initialize();
3255 }
3256
3257 Metachunk* Metaspace::get_initialization_chunk(MetadataType mdtype,
3258 size_t chunk_word_size,
3259 size_t chunk_bunch) {
3260 // Get a chunk from the chunk freelist
3261 Metachunk* chunk = get_chunk_manager(mdtype)->chunk_freelist_allocate(chunk_word_size);
3262 if (chunk != NULL) {
3263 return chunk;
3264 }
3265
3266 return get_space_list(mdtype)->get_new_chunk(chunk_word_size, chunk_word_size, chunk_bunch);
3267 }
3268
3269 void Metaspace::initialize(Mutex* lock, MetaspaceType type) {
3270
3271 assert(space_list() != NULL,
3272 "Metadata VirtualSpaceList has not been initialized");
3273 assert(chunk_manager_metadata() != NULL,
3274 "Metadata ChunkManager has not been initialized");
3275
3276 _vsm = new SpaceManager(NonClassType, lock);
3277 if (_vsm == NULL) {
3278 return;
3279 }
3280 size_t word_size;
3281 size_t class_word_size;
3282 vsm()->get_initial_chunk_sizes(type, &word_size, &class_word_size);
3283
3284 if (using_class_space()) {
3285 assert(class_space_list() != NULL,
3286 "Class VirtualSpaceList has not been initialized");
3287 assert(chunk_manager_class() != NULL,
3288 "Class ChunkManager has not been initialized");
3289
3290 // Allocate SpaceManager for classes.
3291 _class_vsm = new SpaceManager(ClassType, lock);
3292 if (_class_vsm == NULL) {
3293 return;
3294 }
3295 }
3296
3297 MutexLockerEx cl(SpaceManager::expand_lock(), Mutex::_no_safepoint_check_flag);
3298
3299 // Allocate chunk for metadata objects
3300 Metachunk* new_chunk = get_initialization_chunk(NonClassType,
3301 word_size,
3302 vsm()->medium_chunk_bunch());
3303 // For dumping shared archive, report error if allocation has failed.
3304 if (DumpSharedSpaces && new_chunk == NULL) {
3305 report_insufficient_metaspace(MetaspaceAux::committed_bytes() + word_size * BytesPerWord);
3306 }
3307 assert(!DumpSharedSpaces || new_chunk != NULL, "should have enough space for both chunks");
3308 if (new_chunk != NULL) {
3309 // Add to this manager's list of chunks in use and current_chunk().
3310 vsm()->add_chunk(new_chunk, true);
3311 }
3312
3313 // Allocate chunk for class metadata objects
3314 if (using_class_space()) {
3315 Metachunk* class_chunk = get_initialization_chunk(ClassType,
3316 class_word_size,
3317 class_vsm()->medium_chunk_bunch());
3318 if (class_chunk != NULL) {
3319 class_vsm()->add_chunk(class_chunk, true);
3320 } else {
3321 // For dumping shared archive, report error if allocation has failed.
3322 if (DumpSharedSpaces) {
3323 report_insufficient_metaspace(MetaspaceAux::committed_bytes() + class_word_size * BytesPerWord);
3324 }
3325 }
3326 }
3327
3328 _alloc_record_head = NULL;
3329 _alloc_record_tail = NULL;
3330 }
3331
3332 size_t Metaspace::align_word_size_up(size_t word_size) {
3333 size_t byte_size = word_size * wordSize;
3334 return ReservedSpace::allocation_align_size_up(byte_size) / wordSize;
3335 }
3336
3337 MetaWord* Metaspace::allocate(size_t word_size, MetadataType mdtype) {
3338 // DumpSharedSpaces doesn't use class metadata area (yet)
3339 // Also, don't use class_vsm() unless UseCompressedClassPointers is true.
3340 if (is_class_space_allocation(mdtype)) {
3341 return class_vsm()->allocate(word_size);
3342 } else {
3343 return vsm()->allocate(word_size);
3344 }
3345 }
3346
3347 MetaWord* Metaspace::expand_and_allocate(size_t word_size, MetadataType mdtype) {
3348 size_t delta_bytes = MetaspaceGC::delta_capacity_until_GC(word_size * BytesPerWord);
3349 assert(delta_bytes > 0, "Must be");
3350
3351 size_t before = 0;
3352 size_t after = 0;
3353 MetaWord* res;
3354 bool incremented;
3355
3356 // Each thread increments the HWM at most once. Even if the thread fails to increment
3357 // the HWM, an allocation is still attempted. This is because another thread must then
3358 // have incremented the HWM and therefore the allocation might still succeed.
3359 do {
3360 incremented = MetaspaceGC::inc_capacity_until_GC(delta_bytes, &after, &before);
3361 res = allocate(word_size, mdtype);
3362 } while (!incremented && res == NULL);
3363
3364 if (incremented) {
3365 tracer()->report_gc_threshold(before, after,
3366 MetaspaceGCThresholdUpdater::ExpandAndAllocate);
3367 log_trace(gc, metaspace)("Increase capacity to GC from " SIZE_FORMAT " to " SIZE_FORMAT, before, after);
3368 }
3369
3370 return res;
3371 }
3372
3373 // Space allocated in the Metaspace. This may
3374 // be across several metadata virtual spaces.
3375 char* Metaspace::bottom() const {
3376 assert(DumpSharedSpaces, "only useful and valid for dumping shared spaces");
3377 return (char*)vsm()->current_chunk()->bottom();
3378 }
3379
3380 size_t Metaspace::used_words_slow(MetadataType mdtype) const {
3381 if (mdtype == ClassType) {
3382 return using_class_space() ? class_vsm()->sum_used_in_chunks_in_use() : 0;
3383 } else {
3384 return vsm()->sum_used_in_chunks_in_use(); // includes overhead!
3385 }
3386 }
3387
3388 size_t Metaspace::free_words_slow(MetadataType mdtype) const {
3389 if (mdtype == ClassType) {
3390 return using_class_space() ? class_vsm()->sum_free_in_chunks_in_use() : 0;
3391 } else {
3392 return vsm()->sum_free_in_chunks_in_use();
3393 }
3394 }
3395
3396 // Space capacity in the Metaspace. It includes
3397 // space in the list of chunks from which allocations
3398 // have been made. Don't include space in the global freelist and
3399 // in the space available in the dictionary which
3400 // is already counted in some chunk.
3401 size_t Metaspace::capacity_words_slow(MetadataType mdtype) const {
3402 if (mdtype == ClassType) {
3403 return using_class_space() ? class_vsm()->sum_capacity_in_chunks_in_use() : 0;
3404 } else {
3405 return vsm()->sum_capacity_in_chunks_in_use();
3406 }
3407 }
3408
3409 size_t Metaspace::used_bytes_slow(MetadataType mdtype) const {
3410 return used_words_slow(mdtype) * BytesPerWord;
3411 }
3412
3413 size_t Metaspace::capacity_bytes_slow(MetadataType mdtype) const {
3414 return capacity_words_slow(mdtype) * BytesPerWord;
3415 }
3416
3417 size_t Metaspace::allocated_blocks_bytes() const {
3418 return vsm()->allocated_blocks_bytes() +
3419 (using_class_space() ? class_vsm()->allocated_blocks_bytes() : 0);
3420 }
3421
3422 size_t Metaspace::allocated_chunks_bytes() const {
3423 return vsm()->allocated_chunks_bytes() +
3424 (using_class_space() ? class_vsm()->allocated_chunks_bytes() : 0);
3425 }
3426
3427 void Metaspace::deallocate(MetaWord* ptr, size_t word_size, bool is_class) {
3428 assert(!SafepointSynchronize::is_at_safepoint()
3429 || Thread::current()->is_VM_thread(), "should be the VM thread");
3430
3431 if (DumpSharedSpaces && PrintSharedSpaces) {
3432 record_deallocation(ptr, vsm()->get_raw_word_size(word_size));
3433 }
3434
3435 MutexLockerEx ml(vsm()->lock(), Mutex::_no_safepoint_check_flag);
3436
3437 if (word_size < TreeChunk<Metablock, FreeList<Metablock> >::min_size()) {
3438 // Dark matter. Too small for dictionary.
3439 #ifdef ASSERT
3440 Copy::fill_to_words((HeapWord*)ptr, word_size, 0xf5f5f5f5);
3441 #endif
3442 return;
3443 }
3444 if (is_class && using_class_space()) {
3445 class_vsm()->deallocate(ptr, word_size);
3446 } else {
3447 vsm()->deallocate(ptr, word_size);
3448 }
3449 }
3450
3451
3452 MetaWord* Metaspace::allocate(ClassLoaderData* loader_data, size_t word_size,
3453 bool read_only, MetaspaceObj::Type type, TRAPS) {
3454 if (HAS_PENDING_EXCEPTION) {
3455 assert(false, "Should not allocate with exception pending");
3456 return NULL; // caller does a CHECK_NULL too
3457 }
3458
3459 assert(loader_data != NULL, "Should never pass around a NULL loader_data. "
3460 "ClassLoaderData::the_null_class_loader_data() should have been used.");
3461
3462 // Allocate in metaspaces without taking out a lock, because it deadlocks
3463 // with the SymbolTable_lock. Dumping is single threaded for now. We'll have
3464 // to revisit this for application class data sharing.
3465 if (DumpSharedSpaces) {
3466 assert(type > MetaspaceObj::UnknownType && type < MetaspaceObj::_number_of_types, "sanity");
3467 Metaspace* space = read_only ? loader_data->ro_metaspace() : loader_data->rw_metaspace();
3468 MetaWord* result = space->allocate(word_size, NonClassType);
3469 if (result == NULL) {
3470 report_out_of_shared_space(read_only ? SharedReadOnly : SharedReadWrite);
3471 }
3472 if (PrintSharedSpaces) {
3473 space->record_allocation(result, type, space->vsm()->get_raw_word_size(word_size));
3474 }
3475
3476 // Zero initialize.
3477 Copy::fill_to_aligned_words((HeapWord*)result, word_size, 0);
3478
3479 return result;
3480 }
3481
3482 MetadataType mdtype = (type == MetaspaceObj::ClassType) ? ClassType : NonClassType;
3483
3484 // Try to allocate metadata.
3485 MetaWord* result = loader_data->metaspace_non_null()->allocate(word_size, mdtype);
3486
3487 if (result == NULL) {
3488 tracer()->report_metaspace_allocation_failure(loader_data, word_size, type, mdtype);
3489
3490 // Allocation failed.
3491 if (is_init_completed()) {
3492 // Only start a GC if the bootstrapping has completed.
3493
3494 // Try to clean out some memory and retry.
3495 result = Universe::heap()->collector_policy()->satisfy_failed_metadata_allocation(
3496 loader_data, word_size, mdtype);
3497 }
3498 }
3499
3500 if (result == NULL) {
3501 SpaceManager* sm;
3502 if (is_class_space_allocation(mdtype)) {
3503 sm = loader_data->metaspace_non_null()->class_vsm();
3504 } else {
3505 sm = loader_data->metaspace_non_null()->vsm();
3506 }
3507
3508 result = sm->get_small_chunk_and_allocate(word_size);
3509
3510 if (result == NULL) {
3511 report_metadata_oome(loader_data, word_size, type, mdtype, CHECK_NULL);
3512 }
3513 }
3514
3515 // Zero initialize.
3516 Copy::fill_to_aligned_words((HeapWord*)result, word_size, 0);
3517
3518 return result;
3519 }
3520
3521 size_t Metaspace::class_chunk_size(size_t word_size) {
3522 assert(using_class_space(), "Has to use class space");
3523 return class_vsm()->calc_chunk_size(word_size);
3524 }
3525
3526 void Metaspace::report_metadata_oome(ClassLoaderData* loader_data, size_t word_size, MetaspaceObj::Type type, MetadataType mdtype, TRAPS) {
3527 tracer()->report_metadata_oom(loader_data, word_size, type, mdtype);
3528
3529 // If result is still null, we are out of memory.
3530 LogHandle(gc, metaspace, freelist) log;
3531 if (log.is_trace()) {
3532 log.trace("Metaspace allocation failed for size " SIZE_FORMAT, word_size);
3533 ResourceMark rm;
3534 outputStream* out = log.trace_stream();
3535 if (loader_data->metaspace_or_null() != NULL) {
3536 loader_data->dump(out);
3537 }
3538 MetaspaceAux::dump(out);
3539 }
3540
3541 bool out_of_compressed_class_space = false;
3542 if (is_class_space_allocation(mdtype)) {
3543 Metaspace* metaspace = loader_data->metaspace_non_null();
3544 out_of_compressed_class_space =
3545 MetaspaceAux::committed_bytes(Metaspace::ClassType) +
3546 (metaspace->class_chunk_size(word_size) * BytesPerWord) >
3547 CompressedClassSpaceSize;
3548 }
3549
3550 // -XX:+HeapDumpOnOutOfMemoryError and -XX:OnOutOfMemoryError support
3551 const char* space_string = out_of_compressed_class_space ?
3552 "Compressed class space" : "Metaspace";
3553
3554 report_java_out_of_memory(space_string);
3555
3556 if (JvmtiExport::should_post_resource_exhausted()) {
3557 JvmtiExport::post_resource_exhausted(
3558 JVMTI_RESOURCE_EXHAUSTED_OOM_ERROR,
3559 space_string);
3560 }
3561
3562 if (!is_init_completed()) {
3563 vm_exit_during_initialization("OutOfMemoryError", space_string);
3564 }
3565
3566 if (out_of_compressed_class_space) {
3567 THROW_OOP(Universe::out_of_memory_error_class_metaspace());
3568 } else {
3569 THROW_OOP(Universe::out_of_memory_error_metaspace());
3570 }
3571 }
3572
3573 const char* Metaspace::metadata_type_name(Metaspace::MetadataType mdtype) {
3574 switch (mdtype) {
3575 case Metaspace::ClassType: return "Class";
3576 case Metaspace::NonClassType: return "Metadata";
3577 default:
3578 assert(false, "Got bad mdtype: %d", (int) mdtype);
3579 return NULL;
3580 }
3581 }
3582
3583 void Metaspace::record_allocation(void* ptr, MetaspaceObj::Type type, size_t word_size) {
3584 assert(DumpSharedSpaces, "sanity");
3585
3586 int byte_size = (int)word_size * HeapWordSize;
3587 AllocRecord *rec = new AllocRecord((address)ptr, type, byte_size);
3588
3589 if (_alloc_record_head == NULL) {
3590 _alloc_record_head = _alloc_record_tail = rec;
3591 } else if (_alloc_record_tail->_ptr + _alloc_record_tail->_byte_size == (address)ptr) {
3592 _alloc_record_tail->_next = rec;
3593 _alloc_record_tail = rec;
3594 } else {
3595 // slow linear search, but this doesn't happen that often, and only when dumping
3596 for (AllocRecord *old = _alloc_record_head; old; old = old->_next) {
3597 if (old->_ptr == ptr) {
3598 assert(old->_type == MetaspaceObj::DeallocatedType, "sanity");
3599 int remain_bytes = old->_byte_size - byte_size;
3600 assert(remain_bytes >= 0, "sanity");
3601 old->_type = type;
3602
3603 if (remain_bytes == 0) {
3604 delete(rec);
3605 } else {
3606 address remain_ptr = address(ptr) + byte_size;
3607 rec->_ptr = remain_ptr;
3608 rec->_byte_size = remain_bytes;
3609 rec->_type = MetaspaceObj::DeallocatedType;
3610 rec->_next = old->_next;
3611 old->_byte_size = byte_size;
3612 old->_next = rec;
3613 }
3614 return;
3615 }
3616 }
3617 assert(0, "reallocating a freed pointer that was not recorded");
3618 }
3619 }
3620
3621 void Metaspace::record_deallocation(void* ptr, size_t word_size) {
3622 assert(DumpSharedSpaces, "sanity");
3623
3624 for (AllocRecord *rec = _alloc_record_head; rec; rec = rec->_next) {
3625 if (rec->_ptr == ptr) {
3626 assert(rec->_byte_size == (int)word_size * HeapWordSize, "sanity");
3627 rec->_type = MetaspaceObj::DeallocatedType;
3628 return;
3629 }
3630 }
3631
3632 assert(0, "deallocating a pointer that was not recorded");
3633 }
3634
3635 void Metaspace::iterate(Metaspace::AllocRecordClosure *closure) {
3636 assert(DumpSharedSpaces, "unimplemented for !DumpSharedSpaces");
3637
3638 address last_addr = (address)bottom();
3639
3640 for (AllocRecord *rec = _alloc_record_head; rec; rec = rec->_next) {
3641 address ptr = rec->_ptr;
3642 if (last_addr < ptr) {
3643 closure->doit(last_addr, MetaspaceObj::UnknownType, ptr - last_addr);
3644 }
3645 closure->doit(ptr, rec->_type, rec->_byte_size);
3646 last_addr = ptr + rec->_byte_size;
3647 }
3648
3649 address top = ((address)bottom()) + used_bytes_slow(Metaspace::NonClassType);
3650 if (last_addr < top) {
3651 closure->doit(last_addr, MetaspaceObj::UnknownType, top - last_addr);
3652 }
3653 }
3654
3655 void Metaspace::purge(MetadataType mdtype) {
3656 get_space_list(mdtype)->purge(get_chunk_manager(mdtype));
3657 }
3658
3659 void Metaspace::purge() {
3660 MutexLockerEx cl(SpaceManager::expand_lock(),
3661 Mutex::_no_safepoint_check_flag);
3662 purge(NonClassType);
3663 if (using_class_space()) {
3664 purge(ClassType);
3665 }
3666 }
3667
3668 void Metaspace::print_on(outputStream* out) const {
3669 // Print both class virtual space counts and metaspace.
3670 if (Verbose) {
3671 vsm()->print_on(out);
3672 if (using_class_space()) {
3673 class_vsm()->print_on(out);
3674 }
3675 }
3676 }
3677
3678 bool Metaspace::contains(const void* ptr) {
3679 if (UseSharedSpaces && MetaspaceShared::is_in_shared_space(ptr)) {
3680 return true;
3681 }
3682
3683 if (using_class_space() && get_space_list(ClassType)->contains(ptr)) {
3684 return true;
3685 }
3686
3687 return get_space_list(NonClassType)->contains(ptr);
3688 }
3689
3690 void Metaspace::verify() {
3691 vsm()->verify();
3692 if (using_class_space()) {
3693 class_vsm()->verify();
3694 }
3695 }
3696
3697 void Metaspace::dump(outputStream* const out) const {
3698 out->print_cr("\nVirtual space manager: " INTPTR_FORMAT, p2i(vsm()));
3699 vsm()->dump(out);
3700 if (using_class_space()) {
3701 out->print_cr("\nClass space manager: " INTPTR_FORMAT, p2i(class_vsm()));
3702 class_vsm()->dump(out);
3703 }
3704 }
3705
3706 /////////////// Unit tests ///////////////
3707
3708 #ifndef PRODUCT
3709
3710 class TestMetaspaceAuxTest : AllStatic {
3711 public:
3712 static void test_reserved() {
3713 size_t reserved = MetaspaceAux::reserved_bytes();
3714
3715 assert(reserved > 0, "assert");
3716
3717 size_t committed = MetaspaceAux::committed_bytes();
3718 assert(committed <= reserved, "assert");
3719
3720 size_t reserved_metadata = MetaspaceAux::reserved_bytes(Metaspace::NonClassType);
3721 assert(reserved_metadata > 0, "assert");
3722 assert(reserved_metadata <= reserved, "assert");
3723
3724 if (UseCompressedClassPointers) {
3725 size_t reserved_class = MetaspaceAux::reserved_bytes(Metaspace::ClassType);
3726 assert(reserved_class > 0, "assert");
3727 assert(reserved_class < reserved, "assert");
3728 }
3729 }
3730
3731 static void test_committed() {
3732 size_t committed = MetaspaceAux::committed_bytes();
3733
3734 assert(committed > 0, "assert");
3735
3736 size_t reserved = MetaspaceAux::reserved_bytes();
3737 assert(committed <= reserved, "assert");
3738
3739 size_t committed_metadata = MetaspaceAux::committed_bytes(Metaspace::NonClassType);
3740 assert(committed_metadata > 0, "assert");
3741 assert(committed_metadata <= committed, "assert");
3742
3743 if (UseCompressedClassPointers) {
3744 size_t committed_class = MetaspaceAux::committed_bytes(Metaspace::ClassType);
3745 assert(committed_class > 0, "assert");
3746 assert(committed_class < committed, "assert");
3747 }
3748 }
3749
3750 static void test_virtual_space_list_large_chunk() {
3751 VirtualSpaceList* vs_list = new VirtualSpaceList(os::vm_allocation_granularity());
3752 MutexLockerEx cl(SpaceManager::expand_lock(), Mutex::_no_safepoint_check_flag);
3753 // A size larger than VirtualSpaceSize (256k) and add one page to make it _not_ be
3754 // vm_allocation_granularity aligned on Windows.
3755 size_t large_size = (size_t)(2*256*K + (os::vm_page_size()/BytesPerWord));
3756 large_size += (os::vm_page_size()/BytesPerWord);
3757 vs_list->get_new_chunk(large_size, large_size, 0);
3758 }
3759
3760 static void test() {
3761 test_reserved();
3762 test_committed();
3763 test_virtual_space_list_large_chunk();
3764 }
3765 };
3766
3767 void TestMetaspaceAux_test() {
3768 TestMetaspaceAuxTest::test();
3769 }
3770
3771 class TestVirtualSpaceNodeTest {
3772 static void chunk_up(size_t words_left, size_t& num_medium_chunks,
3773 size_t& num_small_chunks,
3774 size_t& num_specialized_chunks) {
3775 num_medium_chunks = words_left / MediumChunk;
3776 words_left = words_left % MediumChunk;
3777
3778 num_small_chunks = words_left / SmallChunk;
3779 words_left = words_left % SmallChunk;
3780 // how many specialized chunks can we get?
3781 num_specialized_chunks = words_left / SpecializedChunk;
3782 assert(words_left % SpecializedChunk == 0, "should be nothing left");
3783 }
3784
3785 public:
3786 static void test() {
3787 MutexLockerEx ml(SpaceManager::expand_lock(), Mutex::_no_safepoint_check_flag);
3788 const size_t vsn_test_size_words = MediumChunk * 4;
3789 const size_t vsn_test_size_bytes = vsn_test_size_words * BytesPerWord;
3790
3791 // The chunk sizes must be multiples of eachother, or this will fail
3792 STATIC_ASSERT(MediumChunk % SmallChunk == 0);
3793 STATIC_ASSERT(SmallChunk % SpecializedChunk == 0);
3794
3795 { // No committed memory in VSN
3796 ChunkManager cm(SpecializedChunk, SmallChunk, MediumChunk);
3797 VirtualSpaceNode vsn(vsn_test_size_bytes);
3798 vsn.initialize();
3799 vsn.retire(&cm);
3800 assert(cm.sum_free_chunks_count() == 0, "did not commit any memory in the VSN");
3801 }
3802
3803 { // All of VSN is committed, half is used by chunks
3804 ChunkManager cm(SpecializedChunk, SmallChunk, MediumChunk);
3805 VirtualSpaceNode vsn(vsn_test_size_bytes);
3806 vsn.initialize();
3807 vsn.expand_by(vsn_test_size_words, vsn_test_size_words);
3808 vsn.get_chunk_vs(MediumChunk);
3809 vsn.get_chunk_vs(MediumChunk);
3810 vsn.retire(&cm);
3811 assert(cm.sum_free_chunks_count() == 2, "should have been memory left for 2 medium chunks");
3812 assert(cm.sum_free_chunks() == 2*MediumChunk, "sizes should add up");
3813 }
3814
3815 const size_t page_chunks = 4 * (size_t)os::vm_page_size() / BytesPerWord;
3816 // This doesn't work for systems with vm_page_size >= 16K.
3817 if (page_chunks < MediumChunk) {
3818 // 4 pages of VSN is committed, some is used by chunks
3819 ChunkManager cm(SpecializedChunk, SmallChunk, MediumChunk);
3820 VirtualSpaceNode vsn(vsn_test_size_bytes);
3821
3822 vsn.initialize();
3823 vsn.expand_by(page_chunks, page_chunks);
3824 vsn.get_chunk_vs(SmallChunk);
3825 vsn.get_chunk_vs(SpecializedChunk);
3826 vsn.retire(&cm);
3827
3828 // committed - used = words left to retire
3829 const size_t words_left = page_chunks - SmallChunk - SpecializedChunk;
3830
3831 size_t num_medium_chunks, num_small_chunks, num_spec_chunks;
3832 chunk_up(words_left, num_medium_chunks, num_small_chunks, num_spec_chunks);
3833
3834 assert(num_medium_chunks == 0, "should not get any medium chunks");
3835 assert(cm.sum_free_chunks_count() == (num_small_chunks + num_spec_chunks), "should be space for 3 chunks");
3836 assert(cm.sum_free_chunks() == words_left, "sizes should add up");
3837 }
3838
3839 { // Half of VSN is committed, a humongous chunk is used
3840 ChunkManager cm(SpecializedChunk, SmallChunk, MediumChunk);
3841 VirtualSpaceNode vsn(vsn_test_size_bytes);
3842 vsn.initialize();
3843 vsn.expand_by(MediumChunk * 2, MediumChunk * 2);
3844 vsn.get_chunk_vs(MediumChunk + SpecializedChunk); // Humongous chunks will be aligned up to MediumChunk + SpecializedChunk
3845 vsn.retire(&cm);
3846
3847 const size_t words_left = MediumChunk * 2 - (MediumChunk + SpecializedChunk);
3848 size_t num_medium_chunks, num_small_chunks, num_spec_chunks;
3849 chunk_up(words_left, num_medium_chunks, num_small_chunks, num_spec_chunks);
3850
3851 assert(num_medium_chunks == 0, "should not get any medium chunks");
3852 assert(cm.sum_free_chunks_count() == (num_small_chunks + num_spec_chunks), "should be space for 3 chunks");
3853 assert(cm.sum_free_chunks() == words_left, "sizes should add up");
3854 }
3855
3856 }
3857
3858 #define assert_is_available_positive(word_size) \
3859 assert(vsn.is_available(word_size), \
3860 #word_size ": " PTR_FORMAT " bytes were not available in " \
3861 "VirtualSpaceNode [" PTR_FORMAT ", " PTR_FORMAT ")", \
3862 (uintptr_t)(word_size * BytesPerWord), p2i(vsn.bottom()), p2i(vsn.end()));
3863
3864 #define assert_is_available_negative(word_size) \
3865 assert(!vsn.is_available(word_size), \
3866 #word_size ": " PTR_FORMAT " bytes should not be available in " \
3867 "VirtualSpaceNode [" PTR_FORMAT ", " PTR_FORMAT ")", \
3868 (uintptr_t)(word_size * BytesPerWord), p2i(vsn.bottom()), p2i(vsn.end()));
3869
3870 static void test_is_available_positive() {
3871 // Reserve some memory.
3872 VirtualSpaceNode vsn(os::vm_allocation_granularity());
3873 assert(vsn.initialize(), "Failed to setup VirtualSpaceNode");
3874
3875 // Commit some memory.
3876 size_t commit_word_size = os::vm_allocation_granularity() / BytesPerWord;
3877 bool expanded = vsn.expand_by(commit_word_size, commit_word_size);
3878 assert(expanded, "Failed to commit");
3879
3880 // Check that is_available accepts the committed size.
3881 assert_is_available_positive(commit_word_size);
3882
3883 // Check that is_available accepts half the committed size.
3884 size_t expand_word_size = commit_word_size / 2;
3885 assert_is_available_positive(expand_word_size);
3886 }
3887
3888 static void test_is_available_negative() {
3889 // Reserve some memory.
3890 VirtualSpaceNode vsn(os::vm_allocation_granularity());
3891 assert(vsn.initialize(), "Failed to setup VirtualSpaceNode");
3892
3893 // Commit some memory.
3894 size_t commit_word_size = os::vm_allocation_granularity() / BytesPerWord;
3895 bool expanded = vsn.expand_by(commit_word_size, commit_word_size);
3896 assert(expanded, "Failed to commit");
3897
3898 // Check that is_available doesn't accept a too large size.
3899 size_t two_times_commit_word_size = commit_word_size * 2;
3900 assert_is_available_negative(two_times_commit_word_size);
3901 }
3902
3903 static void test_is_available_overflow() {
3904 // Reserve some memory.
3905 VirtualSpaceNode vsn(os::vm_allocation_granularity());
3906 assert(vsn.initialize(), "Failed to setup VirtualSpaceNode");
3907
3908 // Commit some memory.
3909 size_t commit_word_size = os::vm_allocation_granularity() / BytesPerWord;
3910 bool expanded = vsn.expand_by(commit_word_size, commit_word_size);
3911 assert(expanded, "Failed to commit");
3912
3913 // Calculate a size that will overflow the virtual space size.
3914 void* virtual_space_max = (void*)(uintptr_t)-1;
3915 size_t bottom_to_max = pointer_delta(virtual_space_max, vsn.bottom(), 1);
3916 size_t overflow_size = bottom_to_max + BytesPerWord;
3917 size_t overflow_word_size = overflow_size / BytesPerWord;
3918
3919 // Check that is_available can handle the overflow.
3920 assert_is_available_negative(overflow_word_size);
3921 }
3922
3923 static void test_is_available() {
3924 TestVirtualSpaceNodeTest::test_is_available_positive();
3925 TestVirtualSpaceNodeTest::test_is_available_negative();
3926 TestVirtualSpaceNodeTest::test_is_available_overflow();
3927 }
3928 };
3929
3930 void TestVirtualSpaceNode_test() {
3931 TestVirtualSpaceNodeTest::test();
3932 TestVirtualSpaceNodeTest::test_is_available();
3933 }
3934 #endif