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_interface/collectedHeap.hpp"
26 #include "memory/allocation.hpp"
27 #include "memory/binaryTreeDictionary.hpp"
28 #include "memory/freeList.hpp"
29 #include "memory/collectorPolicy.hpp"
30 #include "memory/filemap.hpp"
31 #include "memory/freeList.hpp"
32 #include "memory/gcLocker.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, err_msg("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 err_msg(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 err_msg(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
734 // Helper for allocations
735 MetaWord* allocate_work(size_t word_size);
736
737 // Returns a block to the per manager freelist
738 void deallocate(MetaWord* p, size_t word_size);
739
740 // Based on the allocation size and a minimum chunk size,
741 // returned chunk size (for expanding space for chunk allocation).
742 size_t calc_chunk_size(size_t allocation_word_size);
743
744 // Called when an allocation from the current chunk fails.
745 // Gets a new chunk (may require getting a new virtual space),
746 // and allocates from that chunk.
747 MetaWord* grow_and_allocate(size_t word_size);
748
749 // Notify memory usage to MemoryService.
750 void track_metaspace_memory_usage();
751
752 // debugging support.
753
754 void dump(outputStream* const out) const;
755 void print_on(outputStream* st) const;
756 void locked_print_chunks_in_use_on(outputStream* st) const;
757
758 void verify();
759 void verify_chunk_size(Metachunk* chunk);
760 NOT_PRODUCT(void mangle_freed_chunks();)
761 #ifdef ASSERT
762 void verify_allocated_blocks_words();
763 #endif
764
765 size_t get_raw_word_size(size_t word_size) {
766 size_t byte_size = word_size * BytesPerWord;
767
768 size_t raw_bytes_size = MAX2(byte_size, sizeof(Metablock));
769 raw_bytes_size = align_size_up(raw_bytes_size, Metachunk::object_alignment());
770
771 size_t raw_word_size = raw_bytes_size / BytesPerWord;
772 assert(raw_word_size * BytesPerWord == raw_bytes_size, "Size problem");
773
774 return raw_word_size;
775 }
776 };
777
778 uint const SpaceManager::_small_chunk_limit = 4;
779
780 const char* SpaceManager::_expand_lock_name =
781 "SpaceManager chunk allocation lock";
782 const int SpaceManager::_expand_lock_rank = Monitor::leaf - 1;
783 Mutex* const SpaceManager::_expand_lock =
784 new Mutex(SpaceManager::_expand_lock_rank,
785 SpaceManager::_expand_lock_name,
786 Mutex::_allow_vm_block_flag,
787 Monitor::_safepoint_check_never);
788
789 void VirtualSpaceNode::inc_container_count() {
790 assert_lock_strong(SpaceManager::expand_lock());
791 _container_count++;
792 DEBUG_ONLY(verify_container_count();)
793 }
794
795 void VirtualSpaceNode::dec_container_count() {
796 assert_lock_strong(SpaceManager::expand_lock());
797 _container_count--;
798 }
799
800 #ifdef ASSERT
801 void VirtualSpaceNode::verify_container_count() {
802 assert(_container_count == container_count_slow(),
803 err_msg("Inconsistency in container_count _container_count " UINTX_FORMAT
804 " container_count_slow() " UINTX_FORMAT, _container_count, container_count_slow()));
805 }
806 #endif
807
808 // BlockFreelist methods
809
810 BlockFreelist::BlockFreelist() : _dictionary(new BlockTreeDictionary()) {}
811
812 BlockFreelist::~BlockFreelist() {
813 if (Verbose && TraceMetadataChunkAllocation) {
814 dictionary()->print_free_lists(gclog_or_tty);
815 }
816 delete _dictionary;
817 }
818
819 void BlockFreelist::return_block(MetaWord* p, size_t word_size) {
820 Metablock* free_chunk = ::new (p) Metablock(word_size);
821 dictionary()->return_chunk(free_chunk);
822 }
823
824 MetaWord* BlockFreelist::get_block(size_t word_size) {
825 if (word_size < TreeChunk<Metablock, FreeList<Metablock> >::min_size()) {
826 // Dark matter. Too small for dictionary.
827 return NULL;
828 }
829
830 Metablock* free_block =
831 dictionary()->get_chunk(word_size, FreeBlockDictionary<Metablock>::atLeast);
832 if (free_block == NULL) {
833 return NULL;
834 }
835
836 const size_t block_size = free_block->size();
837 if (block_size > WasteMultiplier * word_size) {
838 return_block((MetaWord*)free_block, block_size);
839 return NULL;
840 }
841
842 MetaWord* new_block = (MetaWord*)free_block;
843 assert(block_size >= word_size, "Incorrect size of block from freelist");
844 const size_t unused = block_size - word_size;
845 if (unused >= TreeChunk<Metablock, FreeList<Metablock> >::min_size()) {
846 return_block(new_block + word_size, unused);
847 }
848
849 return new_block;
850 }
851
852 void BlockFreelist::print_on(outputStream* st) const {
853 dictionary()->print_free_lists(st);
854 }
855
856 // VirtualSpaceNode methods
857
858 VirtualSpaceNode::~VirtualSpaceNode() {
859 _rs.release();
860 #ifdef ASSERT
861 size_t word_size = sizeof(*this) / BytesPerWord;
862 Copy::fill_to_words((HeapWord*) this, word_size, 0xf1f1f1f1);
863 #endif
864 }
865
866 size_t VirtualSpaceNode::used_words_in_vs() const {
867 return pointer_delta(top(), bottom(), sizeof(MetaWord));
868 }
869
870 // Space committed in the VirtualSpace
871 size_t VirtualSpaceNode::capacity_words_in_vs() const {
872 return pointer_delta(end(), bottom(), sizeof(MetaWord));
873 }
874
875 size_t VirtualSpaceNode::free_words_in_vs() const {
876 return pointer_delta(end(), top(), sizeof(MetaWord));
877 }
878
879 // Allocates the chunk from the virtual space only.
880 // This interface is also used internally for debugging. Not all
881 // chunks removed here are necessarily used for allocation.
882 Metachunk* VirtualSpaceNode::take_from_committed(size_t chunk_word_size) {
883 // Bottom of the new chunk
884 MetaWord* chunk_limit = top();
885 assert(chunk_limit != NULL, "Not safe to call this method");
886
887 // The virtual spaces are always expanded by the
888 // commit granularity to enforce the following condition.
889 // Without this the is_available check will not work correctly.
890 assert(_virtual_space.committed_size() == _virtual_space.actual_committed_size(),
891 "The committed memory doesn't match the expanded memory.");
892
893 if (!is_available(chunk_word_size)) {
894 if (TraceMetadataChunkAllocation) {
895 gclog_or_tty->print("VirtualSpaceNode::take_from_committed() not available " SIZE_FORMAT " words ", chunk_word_size);
896 // Dump some information about the virtual space that is nearly full
897 print_on(gclog_or_tty);
898 }
899 return NULL;
900 }
901
902 // Take the space (bump top on the current virtual space).
903 inc_top(chunk_word_size);
904
905 // Initialize the chunk
906 Metachunk* result = ::new (chunk_limit) Metachunk(chunk_word_size, this);
907 return result;
908 }
909
910
911 // Expand the virtual space (commit more of the reserved space)
912 bool VirtualSpaceNode::expand_by(size_t min_words, size_t preferred_words) {
913 size_t min_bytes = min_words * BytesPerWord;
914 size_t preferred_bytes = preferred_words * BytesPerWord;
915
916 size_t uncommitted = virtual_space()->reserved_size() - virtual_space()->actual_committed_size();
917
918 if (uncommitted < min_bytes) {
919 return false;
920 }
921
922 size_t commit = MIN2(preferred_bytes, uncommitted);
923 bool result = virtual_space()->expand_by(commit, false);
924
925 assert(result, "Failed to commit memory");
926
927 return result;
928 }
929
930 Metachunk* VirtualSpaceNode::get_chunk_vs(size_t chunk_word_size) {
931 assert_lock_strong(SpaceManager::expand_lock());
932 Metachunk* result = take_from_committed(chunk_word_size);
933 if (result != NULL) {
934 inc_container_count();
935 }
936 return result;
937 }
938
939 bool VirtualSpaceNode::initialize() {
940
941 if (!_rs.is_reserved()) {
942 return false;
943 }
944
945 // These are necessary restriction to make sure that the virtual space always
946 // grows in steps of Metaspace::commit_alignment(). If both base and size are
947 // aligned only the middle alignment of the VirtualSpace is used.
948 assert_is_ptr_aligned(_rs.base(), Metaspace::commit_alignment());
949 assert_is_size_aligned(_rs.size(), Metaspace::commit_alignment());
950
951 // ReservedSpaces marked as special will have the entire memory
952 // pre-committed. Setting a committed size will make sure that
953 // committed_size and actual_committed_size agrees.
954 size_t pre_committed_size = _rs.special() ? _rs.size() : 0;
955
956 bool result = virtual_space()->initialize_with_granularity(_rs, pre_committed_size,
957 Metaspace::commit_alignment());
958 if (result) {
959 assert(virtual_space()->committed_size() == virtual_space()->actual_committed_size(),
960 "Checking that the pre-committed memory was registered by the VirtualSpace");
961
962 set_top((MetaWord*)virtual_space()->low());
963 set_reserved(MemRegion((HeapWord*)_rs.base(),
964 (HeapWord*)(_rs.base() + _rs.size())));
965
966 assert(reserved()->start() == (HeapWord*) _rs.base(),
967 err_msg("Reserved start was not set properly " PTR_FORMAT
968 " != " PTR_FORMAT, p2i(reserved()->start()), p2i(_rs.base())));
969 assert(reserved()->word_size() == _rs.size() / BytesPerWord,
970 err_msg("Reserved size was not set properly " SIZE_FORMAT
971 " != " SIZE_FORMAT, reserved()->word_size(),
972 _rs.size() / BytesPerWord));
973 }
974
975 return result;
976 }
977
978 void VirtualSpaceNode::print_on(outputStream* st) const {
979 size_t used = used_words_in_vs();
980 size_t capacity = capacity_words_in_vs();
981 VirtualSpace* vs = virtual_space();
982 st->print_cr(" space @ " PTR_FORMAT " " SIZE_FORMAT "K, " SIZE_FORMAT_W(3) "%% used "
983 "[" PTR_FORMAT ", " PTR_FORMAT ", "
984 PTR_FORMAT ", " PTR_FORMAT ")",
985 p2i(vs), capacity / K,
986 capacity == 0 ? 0 : used * 100 / capacity,
987 p2i(bottom()), p2i(top()), p2i(end()),
988 p2i(vs->high_boundary()));
989 }
990
991 #ifdef ASSERT
992 void VirtualSpaceNode::mangle() {
993 size_t word_size = capacity_words_in_vs();
994 Copy::fill_to_words((HeapWord*) low(), word_size, 0xf1f1f1f1);
995 }
996 #endif // ASSERT
997
998 // VirtualSpaceList methods
999 // Space allocated from the VirtualSpace
1000
1001 VirtualSpaceList::~VirtualSpaceList() {
1002 VirtualSpaceListIterator iter(virtual_space_list());
1003 while (iter.repeat()) {
1004 VirtualSpaceNode* vsl = iter.get_next();
1005 delete vsl;
1006 }
1007 }
1008
1009 void VirtualSpaceList::inc_reserved_words(size_t v) {
1010 assert_lock_strong(SpaceManager::expand_lock());
1011 _reserved_words = _reserved_words + v;
1012 }
1013 void VirtualSpaceList::dec_reserved_words(size_t v) {
1014 assert_lock_strong(SpaceManager::expand_lock());
1015 _reserved_words = _reserved_words - v;
1016 }
1017
1018 #define assert_committed_below_limit() \
1019 assert(MetaspaceAux::committed_bytes() <= MaxMetaspaceSize, \
1020 err_msg("Too much committed memory. Committed: " SIZE_FORMAT \
1021 " limit (MaxMetaspaceSize): " SIZE_FORMAT, \
1022 MetaspaceAux::committed_bytes(), MaxMetaspaceSize));
1023
1024 void VirtualSpaceList::inc_committed_words(size_t v) {
1025 assert_lock_strong(SpaceManager::expand_lock());
1026 _committed_words = _committed_words + v;
1027
1028 assert_committed_below_limit();
1029 }
1030 void VirtualSpaceList::dec_committed_words(size_t v) {
1031 assert_lock_strong(SpaceManager::expand_lock());
1032 _committed_words = _committed_words - v;
1033
1034 assert_committed_below_limit();
1035 }
1036
1037 void VirtualSpaceList::inc_virtual_space_count() {
1038 assert_lock_strong(SpaceManager::expand_lock());
1039 _virtual_space_count++;
1040 }
1041 void VirtualSpaceList::dec_virtual_space_count() {
1042 assert_lock_strong(SpaceManager::expand_lock());
1043 _virtual_space_count--;
1044 }
1045
1046 void ChunkManager::remove_chunk(Metachunk* chunk) {
1047 size_t word_size = chunk->word_size();
1048 ChunkIndex index = list_index(word_size);
1049 if (index != HumongousIndex) {
1050 free_chunks(index)->remove_chunk(chunk);
1051 } else {
1052 humongous_dictionary()->remove_chunk(chunk);
1053 }
1054
1055 // Chunk is being removed from the chunks free list.
1056 dec_free_chunks_total(chunk->word_size());
1057 }
1058
1059 // Walk the list of VirtualSpaceNodes and delete
1060 // nodes with a 0 container_count. Remove Metachunks in
1061 // the node from their respective freelists.
1062 void VirtualSpaceList::purge(ChunkManager* chunk_manager) {
1063 assert(SafepointSynchronize::is_at_safepoint(), "must be called at safepoint for contains to work");
1064 assert_lock_strong(SpaceManager::expand_lock());
1065 // Don't use a VirtualSpaceListIterator because this
1066 // list is being changed and a straightforward use of an iterator is not safe.
1067 VirtualSpaceNode* purged_vsl = NULL;
1068 VirtualSpaceNode* prev_vsl = virtual_space_list();
1069 VirtualSpaceNode* next_vsl = prev_vsl;
1070 while (next_vsl != NULL) {
1071 VirtualSpaceNode* vsl = next_vsl;
1072 next_vsl = vsl->next();
1073 // Don't free the current virtual space since it will likely
1074 // be needed soon.
1075 if (vsl->container_count() == 0 && vsl != current_virtual_space()) {
1076 // Unlink it from the list
1077 if (prev_vsl == vsl) {
1078 // This is the case of the current node being the first node.
1079 assert(vsl == virtual_space_list(), "Expected to be the first node");
1080 set_virtual_space_list(vsl->next());
1081 } else {
1082 prev_vsl->set_next(vsl->next());
1083 }
1084
1085 vsl->purge(chunk_manager);
1086 dec_reserved_words(vsl->reserved_words());
1087 dec_committed_words(vsl->committed_words());
1088 dec_virtual_space_count();
1089 purged_vsl = vsl;
1090 delete vsl;
1091 } else {
1092 prev_vsl = vsl;
1093 }
1094 }
1095 #ifdef ASSERT
1096 if (purged_vsl != NULL) {
1097 // List should be stable enough to use an iterator here.
1098 VirtualSpaceListIterator iter(virtual_space_list());
1099 while (iter.repeat()) {
1100 VirtualSpaceNode* vsl = iter.get_next();
1101 assert(vsl != purged_vsl, "Purge of vsl failed");
1102 }
1103 }
1104 #endif
1105 }
1106
1107
1108 // This function looks at the mmap regions in the metaspace without locking.
1109 // The chunks are added with store ordering and not deleted except for at
1110 // unloading time during a safepoint.
1111 bool VirtualSpaceList::contains(const void* ptr) {
1112 // List should be stable enough to use an iterator here because removing virtual
1113 // space nodes is only allowed at a safepoint.
1114 VirtualSpaceListIterator iter(virtual_space_list());
1115 while (iter.repeat()) {
1116 VirtualSpaceNode* vsn = iter.get_next();
1117 if (vsn->contains(ptr)) {
1118 return true;
1119 }
1120 }
1121 return false;
1122 }
1123
1124 void VirtualSpaceList::retire_current_virtual_space() {
1125 assert_lock_strong(SpaceManager::expand_lock());
1126
1127 VirtualSpaceNode* vsn = current_virtual_space();
1128
1129 ChunkManager* cm = is_class() ? Metaspace::chunk_manager_class() :
1130 Metaspace::chunk_manager_metadata();
1131
1132 vsn->retire(cm);
1133 }
1134
1135 void VirtualSpaceNode::retire(ChunkManager* chunk_manager) {
1136 for (int i = (int)MediumIndex; i >= (int)ZeroIndex; --i) {
1137 ChunkIndex index = (ChunkIndex)i;
1138 size_t chunk_size = chunk_manager->free_chunks(index)->size();
1139
1140 while (free_words_in_vs() >= chunk_size) {
1141 DEBUG_ONLY(verify_container_count();)
1142 Metachunk* chunk = get_chunk_vs(chunk_size);
1143 assert(chunk != NULL, "allocation should have been successful");
1144
1145 chunk_manager->return_chunks(index, chunk);
1146 chunk_manager->inc_free_chunks_total(chunk_size);
1147 DEBUG_ONLY(verify_container_count();)
1148 }
1149 }
1150 assert(free_words_in_vs() == 0, "should be empty now");
1151 }
1152
1153 VirtualSpaceList::VirtualSpaceList(size_t word_size) :
1154 _is_class(false),
1155 _virtual_space_list(NULL),
1156 _current_virtual_space(NULL),
1157 _reserved_words(0),
1158 _committed_words(0),
1159 _virtual_space_count(0) {
1160 MutexLockerEx cl(SpaceManager::expand_lock(),
1161 Mutex::_no_safepoint_check_flag);
1162 create_new_virtual_space(word_size);
1163 }
1164
1165 VirtualSpaceList::VirtualSpaceList(ReservedSpace rs) :
1166 _is_class(true),
1167 _virtual_space_list(NULL),
1168 _current_virtual_space(NULL),
1169 _reserved_words(0),
1170 _committed_words(0),
1171 _virtual_space_count(0) {
1172 MutexLockerEx cl(SpaceManager::expand_lock(),
1173 Mutex::_no_safepoint_check_flag);
1174 VirtualSpaceNode* class_entry = new VirtualSpaceNode(rs);
1175 bool succeeded = class_entry->initialize();
1176 if (succeeded) {
1177 link_vs(class_entry);
1178 }
1179 }
1180
1181 size_t VirtualSpaceList::free_bytes() {
1182 return virtual_space_list()->free_words_in_vs() * BytesPerWord;
1183 }
1184
1185 // Allocate another meta virtual space and add it to the list.
1186 bool VirtualSpaceList::create_new_virtual_space(size_t vs_word_size) {
1187 assert_lock_strong(SpaceManager::expand_lock());
1188
1189 if (is_class()) {
1190 assert(false, "We currently don't support more than one VirtualSpace for"
1191 " the compressed class space. The initialization of the"
1192 " CCS uses another code path and should not hit this path.");
1193 return false;
1194 }
1195
1196 if (vs_word_size == 0) {
1197 assert(false, "vs_word_size should always be at least _reserve_alignment large.");
1198 return false;
1199 }
1200
1201 // Reserve the space
1202 size_t vs_byte_size = vs_word_size * BytesPerWord;
1203 assert_is_size_aligned(vs_byte_size, Metaspace::reserve_alignment());
1204
1205 // Allocate the meta virtual space and initialize it.
1206 VirtualSpaceNode* new_entry = new VirtualSpaceNode(vs_byte_size);
1207 if (!new_entry->initialize()) {
1208 delete new_entry;
1209 return false;
1210 } else {
1211 assert(new_entry->reserved_words() == vs_word_size,
1212 "Reserved memory size differs from requested memory size");
1213 // ensure lock-free iteration sees fully initialized node
1214 OrderAccess::storestore();
1215 link_vs(new_entry);
1216 return true;
1217 }
1218 }
1219
1220 void VirtualSpaceList::link_vs(VirtualSpaceNode* new_entry) {
1221 if (virtual_space_list() == NULL) {
1222 set_virtual_space_list(new_entry);
1223 } else {
1224 current_virtual_space()->set_next(new_entry);
1225 }
1226 set_current_virtual_space(new_entry);
1227 inc_reserved_words(new_entry->reserved_words());
1228 inc_committed_words(new_entry->committed_words());
1229 inc_virtual_space_count();
1230 #ifdef ASSERT
1231 new_entry->mangle();
1232 #endif
1233 if (TraceMetavirtualspaceAllocation && Verbose) {
1234 VirtualSpaceNode* vsl = current_virtual_space();
1235 vsl->print_on(gclog_or_tty);
1236 }
1237 }
1238
1239 bool VirtualSpaceList::expand_node_by(VirtualSpaceNode* node,
1240 size_t min_words,
1241 size_t preferred_words) {
1242 size_t before = node->committed_words();
1243
1244 bool result = node->expand_by(min_words, preferred_words);
1245
1246 size_t after = node->committed_words();
1247
1248 // after and before can be the same if the memory was pre-committed.
1249 assert(after >= before, "Inconsistency");
1250 inc_committed_words(after - before);
1251
1252 return result;
1253 }
1254
1255 bool VirtualSpaceList::expand_by(size_t min_words, size_t preferred_words) {
1256 assert_is_size_aligned(min_words, Metaspace::commit_alignment_words());
1257 assert_is_size_aligned(preferred_words, Metaspace::commit_alignment_words());
1258 assert(min_words <= preferred_words, "Invalid arguments");
1259
1260 if (!MetaspaceGC::can_expand(min_words, this->is_class())) {
1261 return false;
1262 }
1263
1264 size_t allowed_expansion_words = MetaspaceGC::allowed_expansion();
1265 if (allowed_expansion_words < min_words) {
1266 return false;
1267 }
1268
1269 size_t max_expansion_words = MIN2(preferred_words, allowed_expansion_words);
1270
1271 // Commit more memory from the the current virtual space.
1272 bool vs_expanded = expand_node_by(current_virtual_space(),
1273 min_words,
1274 max_expansion_words);
1275 if (vs_expanded) {
1276 return true;
1277 }
1278 retire_current_virtual_space();
1279
1280 // Get another virtual space.
1281 size_t grow_vs_words = MAX2((size_t)VirtualSpaceSize, preferred_words);
1282 grow_vs_words = align_size_up(grow_vs_words, Metaspace::reserve_alignment_words());
1283
1284 if (create_new_virtual_space(grow_vs_words)) {
1285 if (current_virtual_space()->is_pre_committed()) {
1286 // The memory was pre-committed, so we are done here.
1287 assert(min_words <= current_virtual_space()->committed_words(),
1288 "The new VirtualSpace was pre-committed, so it"
1289 "should be large enough to fit the alloc request.");
1290 return true;
1291 }
1292
1293 return expand_node_by(current_virtual_space(),
1294 min_words,
1295 max_expansion_words);
1296 }
1297
1298 return false;
1299 }
1300
1301 Metachunk* VirtualSpaceList::get_new_chunk(size_t word_size,
1302 size_t grow_chunks_by_words,
1303 size_t medium_chunk_bunch) {
1304
1305 // Allocate a chunk out of the current virtual space.
1306 Metachunk* next = current_virtual_space()->get_chunk_vs(grow_chunks_by_words);
1307
1308 if (next != NULL) {
1309 return next;
1310 }
1311
1312 // The expand amount is currently only determined by the requested sizes
1313 // and not how much committed memory is left in the current virtual space.
1314
1315 size_t min_word_size = align_size_up(grow_chunks_by_words, Metaspace::commit_alignment_words());
1316 size_t preferred_word_size = align_size_up(medium_chunk_bunch, Metaspace::commit_alignment_words());
1317 if (min_word_size >= preferred_word_size) {
1318 // Can happen when humongous chunks are allocated.
1319 preferred_word_size = min_word_size;
1320 }
1321
1322 bool expanded = expand_by(min_word_size, preferred_word_size);
1323 if (expanded) {
1324 next = current_virtual_space()->get_chunk_vs(grow_chunks_by_words);
1325 assert(next != NULL, "The allocation was expected to succeed after the expansion");
1326 }
1327
1328 return next;
1329 }
1330
1331 void VirtualSpaceList::print_on(outputStream* st) const {
1332 if (TraceMetadataChunkAllocation && Verbose) {
1333 VirtualSpaceListIterator iter(virtual_space_list());
1334 while (iter.repeat()) {
1335 VirtualSpaceNode* node = iter.get_next();
1336 node->print_on(st);
1337 }
1338 }
1339 }
1340
1341 // MetaspaceGC methods
1342
1343 // VM_CollectForMetadataAllocation is the vm operation used to GC.
1344 // Within the VM operation after the GC the attempt to allocate the metadata
1345 // should succeed. If the GC did not free enough space for the metaspace
1346 // allocation, the HWM is increased so that another virtualspace will be
1347 // allocated for the metadata. With perm gen the increase in the perm
1348 // gen had bounds, MinMetaspaceExpansion and MaxMetaspaceExpansion. The
1349 // metaspace policy uses those as the small and large steps for the HWM.
1350 //
1351 // After the GC the compute_new_size() for MetaspaceGC is called to
1352 // resize the capacity of the metaspaces. The current implementation
1353 // is based on the flags MinMetaspaceFreeRatio and MaxMetaspaceFreeRatio used
1354 // to resize the Java heap by some GC's. New flags can be implemented
1355 // if really needed. MinMetaspaceFreeRatio is used to calculate how much
1356 // free space is desirable in the metaspace capacity to decide how much
1357 // to increase the HWM. MaxMetaspaceFreeRatio is used to decide how much
1358 // free space is desirable in the metaspace capacity before decreasing
1359 // the HWM.
1360
1361 // Calculate the amount to increase the high water mark (HWM).
1362 // Increase by a minimum amount (MinMetaspaceExpansion) so that
1363 // another expansion is not requested too soon. If that is not
1364 // enough to satisfy the allocation, increase by MaxMetaspaceExpansion.
1365 // If that is still not enough, expand by the size of the allocation
1366 // plus some.
1367 size_t MetaspaceGC::delta_capacity_until_GC(size_t bytes) {
1368 size_t min_delta = MinMetaspaceExpansion;
1369 size_t max_delta = MaxMetaspaceExpansion;
1370 size_t delta = align_size_up(bytes, Metaspace::commit_alignment());
1371
1372 if (delta <= min_delta) {
1373 delta = min_delta;
1374 } else if (delta <= max_delta) {
1375 // Don't want to hit the high water mark on the next
1376 // allocation so make the delta greater than just enough
1377 // for this allocation.
1378 delta = max_delta;
1379 } else {
1380 // This allocation is large but the next ones are probably not
1381 // so increase by the minimum.
1382 delta = delta + min_delta;
1383 }
1384
1385 assert_is_size_aligned(delta, Metaspace::commit_alignment());
1386
1387 return delta;
1388 }
1389
1390 size_t MetaspaceGC::capacity_until_GC() {
1391 size_t value = (size_t)OrderAccess::load_ptr_acquire(&_capacity_until_GC);
1392 assert(value >= MetaspaceSize, "Not initialized properly?");
1393 return value;
1394 }
1395
1396 bool MetaspaceGC::inc_capacity_until_GC(size_t v, size_t* new_cap_until_GC, size_t* old_cap_until_GC) {
1397 assert_is_size_aligned(v, Metaspace::commit_alignment());
1398
1399 size_t capacity_until_GC = (size_t) _capacity_until_GC;
1400 size_t new_value = capacity_until_GC + v;
1401
1402 if (new_value < capacity_until_GC) {
1403 // The addition wrapped around, set new_value to aligned max value.
1404 new_value = align_size_down(max_uintx, Metaspace::commit_alignment());
1405 }
1406
1407 intptr_t expected = (intptr_t) capacity_until_GC;
1408 intptr_t actual = Atomic::cmpxchg_ptr((intptr_t) new_value, &_capacity_until_GC, expected);
1409
1410 if (expected != actual) {
1411 return false;
1412 }
1413
1414 if (new_cap_until_GC != NULL) {
1415 *new_cap_until_GC = new_value;
1416 }
1417 if (old_cap_until_GC != NULL) {
1418 *old_cap_until_GC = capacity_until_GC;
1419 }
1420 return true;
1421 }
1422
1423 size_t MetaspaceGC::dec_capacity_until_GC(size_t v) {
1424 assert_is_size_aligned(v, Metaspace::commit_alignment());
1425
1426 return (size_t)Atomic::add_ptr(-(intptr_t)v, &_capacity_until_GC);
1427 }
1428
1429 void MetaspaceGC::initialize() {
1430 // Set the high-water mark to MaxMetapaceSize during VM initializaton since
1431 // we can't do a GC during initialization.
1432 _capacity_until_GC = MaxMetaspaceSize;
1433 }
1434
1435 void MetaspaceGC::post_initialize() {
1436 // Reset the high-water mark once the VM initialization is done.
1437 _capacity_until_GC = MAX2(MetaspaceAux::committed_bytes(), MetaspaceSize);
1438 }
1439
1440 bool MetaspaceGC::can_expand(size_t word_size, bool is_class) {
1441 // Check if the compressed class space is full.
1442 if (is_class && Metaspace::using_class_space()) {
1443 size_t class_committed = MetaspaceAux::committed_bytes(Metaspace::ClassType);
1444 if (class_committed + word_size * BytesPerWord > CompressedClassSpaceSize) {
1445 return false;
1446 }
1447 }
1448
1449 // Check if the user has imposed a limit on the metaspace memory.
1450 size_t committed_bytes = MetaspaceAux::committed_bytes();
1451 if (committed_bytes + word_size * BytesPerWord > MaxMetaspaceSize) {
1452 return false;
1453 }
1454
1455 return true;
1456 }
1457
1458 size_t MetaspaceGC::allowed_expansion() {
1459 size_t committed_bytes = MetaspaceAux::committed_bytes();
1460 size_t capacity_until_gc = capacity_until_GC();
1461
1462 assert(capacity_until_gc >= committed_bytes,
1463 err_msg("capacity_until_gc: " SIZE_FORMAT " < committed_bytes: " SIZE_FORMAT,
1464 capacity_until_gc, committed_bytes));
1465
1466 size_t left_until_max = MaxMetaspaceSize - committed_bytes;
1467 size_t left_until_GC = capacity_until_gc - committed_bytes;
1468 size_t left_to_commit = MIN2(left_until_GC, left_until_max);
1469
1470 return left_to_commit / BytesPerWord;
1471 }
1472
1473 void MetaspaceGC::compute_new_size() {
1474 assert(_shrink_factor <= 100, "invalid shrink factor");
1475 uint current_shrink_factor = _shrink_factor;
1476 _shrink_factor = 0;
1477
1478 // Using committed_bytes() for used_after_gc is an overestimation, since the
1479 // chunk free lists are included in committed_bytes() and the memory in an
1480 // un-fragmented chunk free list is available for future allocations.
1481 // However, if the chunk free lists becomes fragmented, then the memory may
1482 // not be available for future allocations and the memory is therefore "in use".
1483 // Including the chunk free lists in the definition of "in use" is therefore
1484 // necessary. Not including the chunk free lists can cause capacity_until_GC to
1485 // shrink below committed_bytes() and this has caused serious bugs in the past.
1486 const size_t used_after_gc = MetaspaceAux::committed_bytes();
1487 const size_t capacity_until_GC = MetaspaceGC::capacity_until_GC();
1488
1489 const double minimum_free_percentage = MinMetaspaceFreeRatio / 100.0;
1490 const double maximum_used_percentage = 1.0 - minimum_free_percentage;
1491
1492 const double min_tmp = used_after_gc / maximum_used_percentage;
1493 size_t minimum_desired_capacity =
1494 (size_t)MIN2(min_tmp, double(max_uintx));
1495 // Don't shrink less than the initial generation size
1496 minimum_desired_capacity = MAX2(minimum_desired_capacity,
1497 MetaspaceSize);
1498
1499 if (PrintGCDetails && Verbose) {
1500 gclog_or_tty->print_cr("\nMetaspaceGC::compute_new_size: ");
1501 gclog_or_tty->print_cr(" "
1502 " minimum_free_percentage: %6.2f"
1503 " maximum_used_percentage: %6.2f",
1504 minimum_free_percentage,
1505 maximum_used_percentage);
1506 gclog_or_tty->print_cr(" "
1507 " used_after_gc : %6.1fKB",
1508 used_after_gc / (double) K);
1509 }
1510
1511
1512 size_t shrink_bytes = 0;
1513 if (capacity_until_GC < minimum_desired_capacity) {
1514 // If we have less capacity below the metaspace HWM, then
1515 // increment the HWM.
1516 size_t expand_bytes = minimum_desired_capacity - capacity_until_GC;
1517 expand_bytes = align_size_up(expand_bytes, Metaspace::commit_alignment());
1518 // Don't expand unless it's significant
1519 if (expand_bytes >= MinMetaspaceExpansion) {
1520 size_t new_capacity_until_GC = 0;
1521 bool succeeded = MetaspaceGC::inc_capacity_until_GC(expand_bytes, &new_capacity_until_GC);
1522 assert(succeeded, "Should always succesfully increment HWM when at safepoint");
1523
1524 Metaspace::tracer()->report_gc_threshold(capacity_until_GC,
1525 new_capacity_until_GC,
1526 MetaspaceGCThresholdUpdater::ComputeNewSize);
1527 if (PrintGCDetails && Verbose) {
1528 gclog_or_tty->print_cr(" expanding:"
1529 " minimum_desired_capacity: %6.1fKB"
1530 " expand_bytes: %6.1fKB"
1531 " MinMetaspaceExpansion: %6.1fKB"
1532 " new metaspace HWM: %6.1fKB",
1533 minimum_desired_capacity / (double) K,
1534 expand_bytes / (double) K,
1535 MinMetaspaceExpansion / (double) K,
1536 new_capacity_until_GC / (double) K);
1537 }
1538 }
1539 return;
1540 }
1541
1542 // No expansion, now see if we want to shrink
1543 // We would never want to shrink more than this
1544 assert(capacity_until_GC >= minimum_desired_capacity,
1545 err_msg(SIZE_FORMAT " >= " SIZE_FORMAT,
1546 capacity_until_GC, minimum_desired_capacity));
1547 size_t max_shrink_bytes = capacity_until_GC - minimum_desired_capacity;
1548
1549 // Should shrinking be considered?
1550 if (MaxMetaspaceFreeRatio < 100) {
1551 const double maximum_free_percentage = MaxMetaspaceFreeRatio / 100.0;
1552 const double minimum_used_percentage = 1.0 - maximum_free_percentage;
1553 const double max_tmp = used_after_gc / minimum_used_percentage;
1554 size_t maximum_desired_capacity = (size_t)MIN2(max_tmp, double(max_uintx));
1555 maximum_desired_capacity = MAX2(maximum_desired_capacity,
1556 MetaspaceSize);
1557 if (PrintGCDetails && Verbose) {
1558 gclog_or_tty->print_cr(" "
1559 " maximum_free_percentage: %6.2f"
1560 " minimum_used_percentage: %6.2f",
1561 maximum_free_percentage,
1562 minimum_used_percentage);
1563 gclog_or_tty->print_cr(" "
1564 " minimum_desired_capacity: %6.1fKB"
1565 " maximum_desired_capacity: %6.1fKB",
1566 minimum_desired_capacity / (double) K,
1567 maximum_desired_capacity / (double) K);
1568 }
1569
1570 assert(minimum_desired_capacity <= maximum_desired_capacity,
1571 "sanity check");
1572
1573 if (capacity_until_GC > maximum_desired_capacity) {
1574 // Capacity too large, compute shrinking size
1575 shrink_bytes = capacity_until_GC - maximum_desired_capacity;
1576 // We don't want shrink all the way back to initSize if people call
1577 // System.gc(), because some programs do that between "phases" and then
1578 // we'd just have to grow the heap up again for the next phase. So we
1579 // damp the shrinking: 0% on the first call, 10% on the second call, 40%
1580 // on the third call, and 100% by the fourth call. But if we recompute
1581 // size without shrinking, it goes back to 0%.
1582 shrink_bytes = shrink_bytes / 100 * current_shrink_factor;
1583
1584 shrink_bytes = align_size_down(shrink_bytes, Metaspace::commit_alignment());
1585
1586 assert(shrink_bytes <= max_shrink_bytes,
1587 err_msg("invalid shrink size " SIZE_FORMAT " not <= " SIZE_FORMAT,
1588 shrink_bytes, max_shrink_bytes));
1589 if (current_shrink_factor == 0) {
1590 _shrink_factor = 10;
1591 } else {
1592 _shrink_factor = MIN2(current_shrink_factor * 4, (uint) 100);
1593 }
1594 if (PrintGCDetails && Verbose) {
1595 gclog_or_tty->print_cr(" "
1596 " shrinking:"
1597 " initSize: %.1fK"
1598 " maximum_desired_capacity: %.1fK",
1599 MetaspaceSize / (double) K,
1600 maximum_desired_capacity / (double) K);
1601 gclog_or_tty->print_cr(" "
1602 " shrink_bytes: %.1fK"
1603 " current_shrink_factor: %d"
1604 " new shrink factor: %d"
1605 " MinMetaspaceExpansion: %.1fK",
1606 shrink_bytes / (double) K,
1607 current_shrink_factor,
1608 _shrink_factor,
1609 MinMetaspaceExpansion / (double) K);
1610 }
1611 }
1612 }
1613
1614 // Don't shrink unless it's significant
1615 if (shrink_bytes >= MinMetaspaceExpansion &&
1616 ((capacity_until_GC - shrink_bytes) >= MetaspaceSize)) {
1617 size_t new_capacity_until_GC = MetaspaceGC::dec_capacity_until_GC(shrink_bytes);
1618 Metaspace::tracer()->report_gc_threshold(capacity_until_GC,
1619 new_capacity_until_GC,
1620 MetaspaceGCThresholdUpdater::ComputeNewSize);
1621 }
1622 }
1623
1624 // Metadebug methods
1625
1626 void Metadebug::init_allocation_fail_alot_count() {
1627 if (MetadataAllocationFailALot) {
1628 _allocation_fail_alot_count =
1629 1+(long)((double)MetadataAllocationFailALotInterval*os::random()/(max_jint+1.0));
1630 }
1631 }
1632
1633 #ifdef ASSERT
1634 bool Metadebug::test_metadata_failure() {
1635 if (MetadataAllocationFailALot &&
1636 Threads::is_vm_complete()) {
1637 if (_allocation_fail_alot_count > 0) {
1638 _allocation_fail_alot_count--;
1639 } else {
1640 if (TraceMetadataChunkAllocation && Verbose) {
1641 gclog_or_tty->print_cr("Metadata allocation failing for "
1642 "MetadataAllocationFailALot");
1643 }
1644 init_allocation_fail_alot_count();
1645 return true;
1646 }
1647 }
1648 return false;
1649 }
1650 #endif
1651
1652 // ChunkManager methods
1653
1654 size_t ChunkManager::free_chunks_total_words() {
1655 return _free_chunks_total;
1656 }
1657
1658 size_t ChunkManager::free_chunks_total_bytes() {
1659 return free_chunks_total_words() * BytesPerWord;
1660 }
1661
1662 size_t ChunkManager::free_chunks_count() {
1663 #ifdef ASSERT
1664 if (!UseConcMarkSweepGC && !SpaceManager::expand_lock()->is_locked()) {
1665 MutexLockerEx cl(SpaceManager::expand_lock(),
1666 Mutex::_no_safepoint_check_flag);
1667 // This lock is only needed in debug because the verification
1668 // of the _free_chunks_totals walks the list of free chunks
1669 slow_locked_verify_free_chunks_count();
1670 }
1671 #endif
1672 return _free_chunks_count;
1673 }
1674
1675 void ChunkManager::locked_verify_free_chunks_total() {
1676 assert_lock_strong(SpaceManager::expand_lock());
1677 assert(sum_free_chunks() == _free_chunks_total,
1678 err_msg("_free_chunks_total " SIZE_FORMAT " is not the"
1679 " same as sum " SIZE_FORMAT, _free_chunks_total,
1680 sum_free_chunks()));
1681 }
1682
1683 void ChunkManager::verify_free_chunks_total() {
1684 MutexLockerEx cl(SpaceManager::expand_lock(),
1685 Mutex::_no_safepoint_check_flag);
1686 locked_verify_free_chunks_total();
1687 }
1688
1689 void ChunkManager::locked_verify_free_chunks_count() {
1690 assert_lock_strong(SpaceManager::expand_lock());
1691 assert(sum_free_chunks_count() == _free_chunks_count,
1692 err_msg("_free_chunks_count " SIZE_FORMAT " is not the"
1693 " same as sum " SIZE_FORMAT, _free_chunks_count,
1694 sum_free_chunks_count()));
1695 }
1696
1697 void ChunkManager::verify_free_chunks_count() {
1698 #ifdef ASSERT
1699 MutexLockerEx cl(SpaceManager::expand_lock(),
1700 Mutex::_no_safepoint_check_flag);
1701 locked_verify_free_chunks_count();
1702 #endif
1703 }
1704
1705 void ChunkManager::verify() {
1706 MutexLockerEx cl(SpaceManager::expand_lock(),
1707 Mutex::_no_safepoint_check_flag);
1708 locked_verify();
1709 }
1710
1711 void ChunkManager::locked_verify() {
1712 locked_verify_free_chunks_count();
1713 locked_verify_free_chunks_total();
1714 }
1715
1716 void ChunkManager::locked_print_free_chunks(outputStream* st) {
1717 assert_lock_strong(SpaceManager::expand_lock());
1718 st->print_cr("Free chunk total " SIZE_FORMAT " count " SIZE_FORMAT,
1719 _free_chunks_total, _free_chunks_count);
1720 }
1721
1722 void ChunkManager::locked_print_sum_free_chunks(outputStream* st) {
1723 assert_lock_strong(SpaceManager::expand_lock());
1724 st->print_cr("Sum free chunk total " SIZE_FORMAT " count " SIZE_FORMAT,
1725 sum_free_chunks(), sum_free_chunks_count());
1726 }
1727 ChunkList* ChunkManager::free_chunks(ChunkIndex index) {
1728 return &_free_chunks[index];
1729 }
1730
1731 // These methods that sum the free chunk lists are used in printing
1732 // methods that are used in product builds.
1733 size_t ChunkManager::sum_free_chunks() {
1734 assert_lock_strong(SpaceManager::expand_lock());
1735 size_t result = 0;
1736 for (ChunkIndex i = ZeroIndex; i < NumberOfFreeLists; i = next_chunk_index(i)) {
1737 ChunkList* list = free_chunks(i);
1738
1739 if (list == NULL) {
1740 continue;
1741 }
1742
1743 result = result + list->count() * list->size();
1744 }
1745 result = result + humongous_dictionary()->total_size();
1746 return result;
1747 }
1748
1749 size_t ChunkManager::sum_free_chunks_count() {
1750 assert_lock_strong(SpaceManager::expand_lock());
1751 size_t count = 0;
1752 for (ChunkIndex i = ZeroIndex; i < NumberOfFreeLists; i = next_chunk_index(i)) {
1753 ChunkList* list = free_chunks(i);
1754 if (list == NULL) {
1755 continue;
1756 }
1757 count = count + list->count();
1758 }
1759 count = count + humongous_dictionary()->total_free_blocks();
1760 return count;
1761 }
1762
1763 ChunkList* ChunkManager::find_free_chunks_list(size_t word_size) {
1764 ChunkIndex index = list_index(word_size);
1765 assert(index < HumongousIndex, "No humongous list");
1766 return free_chunks(index);
1767 }
1768
1769 Metachunk* ChunkManager::free_chunks_get(size_t word_size) {
1770 assert_lock_strong(SpaceManager::expand_lock());
1771
1772 slow_locked_verify();
1773
1774 Metachunk* chunk = NULL;
1775 if (list_index(word_size) != HumongousIndex) {
1776 ChunkList* free_list = find_free_chunks_list(word_size);
1777 assert(free_list != NULL, "Sanity check");
1778
1779 chunk = free_list->head();
1780
1781 if (chunk == NULL) {
1782 return NULL;
1783 }
1784
1785 // Remove the chunk as the head of the list.
1786 free_list->remove_chunk(chunk);
1787
1788 if (TraceMetadataChunkAllocation && Verbose) {
1789 gclog_or_tty->print_cr("ChunkManager::free_chunks_get: free_list "
1790 PTR_FORMAT " head " PTR_FORMAT " size " SIZE_FORMAT,
1791 p2i(free_list), p2i(chunk), chunk->word_size());
1792 }
1793 } else {
1794 chunk = humongous_dictionary()->get_chunk(
1795 word_size,
1796 FreeBlockDictionary<Metachunk>::atLeast);
1797
1798 if (chunk == NULL) {
1799 return NULL;
1800 }
1801
1802 if (TraceMetadataHumongousAllocation) {
1803 size_t waste = chunk->word_size() - word_size;
1804 gclog_or_tty->print_cr("Free list allocate humongous chunk size "
1805 SIZE_FORMAT " for requested size " SIZE_FORMAT
1806 " waste " SIZE_FORMAT,
1807 chunk->word_size(), word_size, waste);
1808 }
1809 }
1810
1811 // Chunk is being removed from the chunks free list.
1812 dec_free_chunks_total(chunk->word_size());
1813
1814 // Remove it from the links to this freelist
1815 chunk->set_next(NULL);
1816 chunk->set_prev(NULL);
1817 #ifdef ASSERT
1818 // Chunk is no longer on any freelist. Setting to false make container_count_slow()
1819 // work.
1820 chunk->set_is_tagged_free(false);
1821 #endif
1822 chunk->container()->inc_container_count();
1823
1824 slow_locked_verify();
1825 return chunk;
1826 }
1827
1828 Metachunk* ChunkManager::chunk_freelist_allocate(size_t word_size) {
1829 assert_lock_strong(SpaceManager::expand_lock());
1830 slow_locked_verify();
1831
1832 // Take from the beginning of the list
1833 Metachunk* chunk = free_chunks_get(word_size);
1834 if (chunk == NULL) {
1835 return NULL;
1836 }
1837
1838 assert((word_size <= chunk->word_size()) ||
1839 list_index(chunk->word_size() == HumongousIndex),
1840 "Non-humongous variable sized chunk");
1841 if (TraceMetadataChunkAllocation) {
1842 size_t list_count;
1843 if (list_index(word_size) < HumongousIndex) {
1844 ChunkList* list = find_free_chunks_list(word_size);
1845 list_count = list->count();
1846 } else {
1847 list_count = humongous_dictionary()->total_count();
1848 }
1849 gclog_or_tty->print("ChunkManager::chunk_freelist_allocate: " PTR_FORMAT " chunk "
1850 PTR_FORMAT " size " SIZE_FORMAT " count " SIZE_FORMAT " ",
1851 p2i(this), p2i(chunk), chunk->word_size(), list_count);
1852 locked_print_free_chunks(gclog_or_tty);
1853 }
1854
1855 return chunk;
1856 }
1857
1858 void ChunkManager::print_on(outputStream* out) const {
1859 if (PrintFLSStatistics != 0) {
1860 const_cast<ChunkManager *>(this)->humongous_dictionary()->report_statistics();
1861 }
1862 }
1863
1864 // SpaceManager methods
1865
1866 void SpaceManager::get_initial_chunk_sizes(Metaspace::MetaspaceType type,
1867 size_t* chunk_word_size,
1868 size_t* class_chunk_word_size) {
1869 switch (type) {
1870 case Metaspace::BootMetaspaceType:
1871 *chunk_word_size = Metaspace::first_chunk_word_size();
1872 *class_chunk_word_size = Metaspace::first_class_chunk_word_size();
1873 break;
1874 case Metaspace::ROMetaspaceType:
1875 *chunk_word_size = SharedReadOnlySize / wordSize;
1876 *class_chunk_word_size = ClassSpecializedChunk;
1877 break;
1878 case Metaspace::ReadWriteMetaspaceType:
1879 *chunk_word_size = SharedReadWriteSize / wordSize;
1880 *class_chunk_word_size = ClassSpecializedChunk;
1881 break;
1882 case Metaspace::AnonymousMetaspaceType:
1883 case Metaspace::ReflectionMetaspaceType:
1884 *chunk_word_size = SpecializedChunk;
1885 *class_chunk_word_size = ClassSpecializedChunk;
1886 break;
1887 default:
1888 *chunk_word_size = SmallChunk;
1889 *class_chunk_word_size = ClassSmallChunk;
1890 break;
1891 }
1892 assert(*chunk_word_size != 0 && *class_chunk_word_size != 0,
1893 err_msg("Initial chunks sizes bad: data " SIZE_FORMAT
1894 " class " SIZE_FORMAT,
1895 *chunk_word_size, *class_chunk_word_size));
1896 }
1897
1898 size_t SpaceManager::sum_free_in_chunks_in_use() const {
1899 MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag);
1900 size_t free = 0;
1901 for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) {
1902 Metachunk* chunk = chunks_in_use(i);
1903 while (chunk != NULL) {
1904 free += chunk->free_word_size();
1905 chunk = chunk->next();
1906 }
1907 }
1908 return free;
1909 }
1910
1911 size_t SpaceManager::sum_waste_in_chunks_in_use() const {
1912 MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag);
1913 size_t result = 0;
1914 for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) {
1915 result += sum_waste_in_chunks_in_use(i);
1916 }
1917
1918 return result;
1919 }
1920
1921 size_t SpaceManager::sum_waste_in_chunks_in_use(ChunkIndex index) const {
1922 size_t result = 0;
1923 Metachunk* chunk = chunks_in_use(index);
1924 // Count the free space in all the chunk but not the
1925 // current chunk from which allocations are still being done.
1926 while (chunk != NULL) {
1927 if (chunk != current_chunk()) {
1928 result += chunk->free_word_size();
1929 }
1930 chunk = chunk->next();
1931 }
1932 return result;
1933 }
1934
1935 size_t SpaceManager::sum_capacity_in_chunks_in_use() const {
1936 // For CMS use "allocated_chunks_words()" which does not need the
1937 // Metaspace lock. For the other collectors sum over the
1938 // lists. Use both methods as a check that "allocated_chunks_words()"
1939 // is correct. That is, sum_capacity_in_chunks() is too expensive
1940 // to use in the product and allocated_chunks_words() should be used
1941 // but allow for checking that allocated_chunks_words() returns the same
1942 // value as sum_capacity_in_chunks_in_use() which is the definitive
1943 // answer.
1944 if (UseConcMarkSweepGC) {
1945 return allocated_chunks_words();
1946 } else {
1947 MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag);
1948 size_t sum = 0;
1949 for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) {
1950 Metachunk* chunk = chunks_in_use(i);
1951 while (chunk != NULL) {
1952 sum += chunk->word_size();
1953 chunk = chunk->next();
1954 }
1955 }
1956 return sum;
1957 }
1958 }
1959
1960 size_t SpaceManager::sum_count_in_chunks_in_use() {
1961 size_t count = 0;
1962 for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) {
1963 count = count + sum_count_in_chunks_in_use(i);
1964 }
1965
1966 return count;
1967 }
1968
1969 size_t SpaceManager::sum_count_in_chunks_in_use(ChunkIndex i) {
1970 size_t count = 0;
1971 Metachunk* chunk = chunks_in_use(i);
1972 while (chunk != NULL) {
1973 count++;
1974 chunk = chunk->next();
1975 }
1976 return count;
1977 }
1978
1979
1980 size_t SpaceManager::sum_used_in_chunks_in_use() const {
1981 MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag);
1982 size_t used = 0;
1983 for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) {
1984 Metachunk* chunk = chunks_in_use(i);
1985 while (chunk != NULL) {
1986 used += chunk->used_word_size();
1987 chunk = chunk->next();
1988 }
1989 }
1990 return used;
1991 }
1992
1993 void SpaceManager::locked_print_chunks_in_use_on(outputStream* st) const {
1994
1995 for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) {
1996 Metachunk* chunk = chunks_in_use(i);
1997 st->print("SpaceManager: %s " PTR_FORMAT,
1998 chunk_size_name(i), p2i(chunk));
1999 if (chunk != NULL) {
2000 st->print_cr(" free " SIZE_FORMAT,
2001 chunk->free_word_size());
2002 } else {
2003 st->cr();
2004 }
2005 }
2006
2007 chunk_manager()->locked_print_free_chunks(st);
2008 chunk_manager()->locked_print_sum_free_chunks(st);
2009 }
2010
2011 size_t SpaceManager::calc_chunk_size(size_t word_size) {
2012
2013 // Decide between a small chunk and a medium chunk. Up to
2014 // _small_chunk_limit small chunks can be allocated.
2015 // After that a medium chunk is preferred.
2016 size_t chunk_word_size;
2017 if (chunks_in_use(MediumIndex) == NULL &&
2018 sum_count_in_chunks_in_use(SmallIndex) < _small_chunk_limit) {
2019 chunk_word_size = (size_t) small_chunk_size();
2020 if (word_size + Metachunk::overhead() > small_chunk_size()) {
2021 chunk_word_size = medium_chunk_size();
2022 }
2023 } else {
2024 chunk_word_size = medium_chunk_size();
2025 }
2026
2027 // Might still need a humongous chunk. Enforce
2028 // humongous allocations sizes to be aligned up to
2029 // the smallest chunk size.
2030 size_t if_humongous_sized_chunk =
2031 align_size_up(word_size + Metachunk::overhead(),
2032 smallest_chunk_size());
2033 chunk_word_size =
2034 MAX2((size_t) chunk_word_size, if_humongous_sized_chunk);
2035
2036 assert(!SpaceManager::is_humongous(word_size) ||
2037 chunk_word_size == if_humongous_sized_chunk,
2038 err_msg("Size calculation is wrong, word_size " SIZE_FORMAT
2039 " chunk_word_size " SIZE_FORMAT,
2040 word_size, chunk_word_size));
2041 if (TraceMetadataHumongousAllocation &&
2042 SpaceManager::is_humongous(word_size)) {
2043 gclog_or_tty->print_cr("Metadata humongous allocation:");
2044 gclog_or_tty->print_cr(" word_size " PTR_FORMAT, word_size);
2045 gclog_or_tty->print_cr(" chunk_word_size " PTR_FORMAT,
2046 chunk_word_size);
2047 gclog_or_tty->print_cr(" chunk overhead " PTR_FORMAT,
2048 Metachunk::overhead());
2049 }
2050 return chunk_word_size;
2051 }
2052
2053 void SpaceManager::track_metaspace_memory_usage() {
2054 if (is_init_completed()) {
2055 if (is_class()) {
2056 MemoryService::track_compressed_class_memory_usage();
2057 }
2058 MemoryService::track_metaspace_memory_usage();
2059 }
2060 }
2061
2062 /*
2063 * The policy is to allocate up to _small_chunk_limit small chunks
2064 * after which only medium chunks are allocated. This is done to
2065 * reduce fragmentation. In some cases, this can result in a lot
2066 * of small chunks being allocated to the point where it's not
2067 * possible to expand. If this happens, there may be no medium chunks
2068 * available and OOME would be thrown. Instead of doing that,
2069 * if the allocation request size fits in a small chunk, an attempt
2070 * will be made to allocate a small chunk.
2071 */
2072 MetaWord* SpaceManager::grow_and_allocate(size_t word_size) {
2073 assert(vs_list()->current_virtual_space() != NULL,
2074 "Should have been set");
2075 assert(current_chunk() == NULL ||
2076 current_chunk()->allocate(word_size) == NULL,
2077 "Don't need to expand");
2078 MutexLockerEx cl(SpaceManager::expand_lock(), Mutex::_no_safepoint_check_flag);
2079
2080 if (TraceMetadataChunkAllocation && Verbose) {
2081 size_t words_left = 0;
2082 size_t words_used = 0;
2083 if (current_chunk() != NULL) {
2084 words_left = current_chunk()->free_word_size();
2085 words_used = current_chunk()->used_word_size();
2086 }
2087 gclog_or_tty->print_cr("SpaceManager::grow_and_allocate for " SIZE_FORMAT
2088 " words " SIZE_FORMAT " words used " SIZE_FORMAT
2089 " words left",
2090 word_size, words_used, words_left);
2091 }
2092
2093 // Get another chunk
2094 size_t grow_chunks_by_words = calc_chunk_size(word_size);
2095 Metachunk* next = get_new_chunk(word_size, grow_chunks_by_words);
2096
2097 MetaWord* mem = NULL;
2098
2099 if (next == NULL &&
2100 word_size + Metachunk::overhead() <= small_chunk_size() &&
2101 grow_chunks_by_words == medium_chunk_size()) {
2102 /*
2103 * There are no medium chunks available but a small chunk is big enough.
2104 * See if a small chunk is available.
2105 */
2106 next = get_new_chunk(word_size, small_chunk_size());
2107 }
2108
2109 // If a chunk was available, add it to the in-use chunk list
2110 // and do an allocation from it.
2111 if (next != NULL) {
2112 // Add to this manager's list of chunks in use.
2113 add_chunk(next, false);
2114 mem = next->allocate(word_size);
2115 }
2116
2117 // Track metaspace memory usage statistic.
2118 track_metaspace_memory_usage();
2119
2120 return mem;
2121 }
2122
2123 void SpaceManager::print_on(outputStream* st) const {
2124
2125 for (ChunkIndex i = ZeroIndex;
2126 i < NumberOfInUseLists ;
2127 i = next_chunk_index(i) ) {
2128 st->print_cr(" chunks_in_use " PTR_FORMAT " chunk size " SIZE_FORMAT,
2129 p2i(chunks_in_use(i)),
2130 chunks_in_use(i) == NULL ? 0 : chunks_in_use(i)->word_size());
2131 }
2132 st->print_cr(" waste: Small " SIZE_FORMAT " Medium " SIZE_FORMAT
2133 " Humongous " SIZE_FORMAT,
2134 sum_waste_in_chunks_in_use(SmallIndex),
2135 sum_waste_in_chunks_in_use(MediumIndex),
2136 sum_waste_in_chunks_in_use(HumongousIndex));
2137 // block free lists
2138 if (block_freelists() != NULL) {
2139 st->print_cr("total in block free lists " SIZE_FORMAT,
2140 block_freelists()->total_size());
2141 }
2142 }
2143
2144 SpaceManager::SpaceManager(Metaspace::MetadataType mdtype,
2145 Mutex* lock) :
2146 _mdtype(mdtype),
2147 _allocated_blocks_words(0),
2148 _allocated_chunks_words(0),
2149 _allocated_chunks_count(0),
2150 _lock(lock)
2151 {
2152 initialize();
2153 }
2154
2155 void SpaceManager::inc_size_metrics(size_t words) {
2156 assert_lock_strong(SpaceManager::expand_lock());
2157 // Total of allocated Metachunks and allocated Metachunks count
2158 // for each SpaceManager
2159 _allocated_chunks_words = _allocated_chunks_words + words;
2160 _allocated_chunks_count++;
2161 // Global total of capacity in allocated Metachunks
2162 MetaspaceAux::inc_capacity(mdtype(), words);
2163 // Global total of allocated Metablocks.
2164 // used_words_slow() includes the overhead in each
2165 // Metachunk so include it in the used when the
2166 // Metachunk is first added (so only added once per
2167 // Metachunk).
2168 MetaspaceAux::inc_used(mdtype(), Metachunk::overhead());
2169 }
2170
2171 void SpaceManager::inc_used_metrics(size_t words) {
2172 // Add to the per SpaceManager total
2173 Atomic::add_ptr(words, &_allocated_blocks_words);
2174 // Add to the global total
2175 MetaspaceAux::inc_used(mdtype(), words);
2176 }
2177
2178 void SpaceManager::dec_total_from_size_metrics() {
2179 MetaspaceAux::dec_capacity(mdtype(), allocated_chunks_words());
2180 MetaspaceAux::dec_used(mdtype(), allocated_blocks_words());
2181 // Also deduct the overhead per Metachunk
2182 MetaspaceAux::dec_used(mdtype(), allocated_chunks_count() * Metachunk::overhead());
2183 }
2184
2185 void SpaceManager::initialize() {
2186 Metadebug::init_allocation_fail_alot_count();
2187 for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) {
2188 _chunks_in_use[i] = NULL;
2189 }
2190 _current_chunk = NULL;
2191 if (TraceMetadataChunkAllocation && Verbose) {
2192 gclog_or_tty->print_cr("SpaceManager(): " PTR_FORMAT, p2i(this));
2193 }
2194 }
2195
2196 void ChunkManager::return_chunks(ChunkIndex index, Metachunk* chunks) {
2197 if (chunks == NULL) {
2198 return;
2199 }
2200 ChunkList* list = free_chunks(index);
2201 assert(list->size() == chunks->word_size(), "Mismatch in chunk sizes");
2202 assert_lock_strong(SpaceManager::expand_lock());
2203 Metachunk* cur = chunks;
2204
2205 // This returns chunks one at a time. If a new
2206 // class List can be created that is a base class
2207 // of FreeList then something like FreeList::prepend()
2208 // can be used in place of this loop
2209 while (cur != NULL) {
2210 assert(cur->container() != NULL, "Container should have been set");
2211 cur->container()->dec_container_count();
2212 // Capture the next link before it is changed
2213 // by the call to return_chunk_at_head();
2214 Metachunk* next = cur->next();
2215 DEBUG_ONLY(cur->set_is_tagged_free(true);)
2216 list->return_chunk_at_head(cur);
2217 cur = next;
2218 }
2219 }
2220
2221 SpaceManager::~SpaceManager() {
2222 // This call this->_lock which can't be done while holding expand_lock()
2223 assert(sum_capacity_in_chunks_in_use() == allocated_chunks_words(),
2224 err_msg("sum_capacity_in_chunks_in_use() " SIZE_FORMAT
2225 " allocated_chunks_words() " SIZE_FORMAT,
2226 sum_capacity_in_chunks_in_use(), allocated_chunks_words()));
2227
2228 MutexLockerEx fcl(SpaceManager::expand_lock(),
2229 Mutex::_no_safepoint_check_flag);
2230
2231 chunk_manager()->slow_locked_verify();
2232
2233 dec_total_from_size_metrics();
2234
2235 if (TraceMetadataChunkAllocation && Verbose) {
2236 gclog_or_tty->print_cr("~SpaceManager(): " PTR_FORMAT, p2i(this));
2237 locked_print_chunks_in_use_on(gclog_or_tty);
2238 }
2239
2240 // Do not mangle freed Metachunks. The chunk size inside Metachunks
2241 // is during the freeing of a VirtualSpaceNodes.
2242
2243 // Have to update before the chunks_in_use lists are emptied
2244 // below.
2245 chunk_manager()->inc_free_chunks_total(allocated_chunks_words(),
2246 sum_count_in_chunks_in_use());
2247
2248 // Add all the chunks in use by this space manager
2249 // to the global list of free chunks.
2250
2251 // Follow each list of chunks-in-use and add them to the
2252 // free lists. Each list is NULL terminated.
2253
2254 for (ChunkIndex i = ZeroIndex; i < HumongousIndex; i = next_chunk_index(i)) {
2255 if (TraceMetadataChunkAllocation && Verbose) {
2256 gclog_or_tty->print_cr("returned " SIZE_FORMAT " %s chunks to freelist",
2257 sum_count_in_chunks_in_use(i),
2258 chunk_size_name(i));
2259 }
2260 Metachunk* chunks = chunks_in_use(i);
2261 chunk_manager()->return_chunks(i, chunks);
2262 set_chunks_in_use(i, NULL);
2263 if (TraceMetadataChunkAllocation && Verbose) {
2264 gclog_or_tty->print_cr("updated freelist count " SSIZE_FORMAT " %s",
2265 chunk_manager()->free_chunks(i)->count(),
2266 chunk_size_name(i));
2267 }
2268 assert(i != HumongousIndex, "Humongous chunks are handled explicitly later");
2269 }
2270
2271 // The medium chunk case may be optimized by passing the head and
2272 // tail of the medium chunk list to add_at_head(). The tail is often
2273 // the current chunk but there are probably exceptions.
2274
2275 // Humongous chunks
2276 if (TraceMetadataChunkAllocation && Verbose) {
2277 gclog_or_tty->print_cr("returned " SIZE_FORMAT " %s humongous chunks to dictionary",
2278 sum_count_in_chunks_in_use(HumongousIndex),
2279 chunk_size_name(HumongousIndex));
2280 gclog_or_tty->print("Humongous chunk dictionary: ");
2281 }
2282 // Humongous chunks are never the current chunk.
2283 Metachunk* humongous_chunks = chunks_in_use(HumongousIndex);
2284
2285 while (humongous_chunks != NULL) {
2286 #ifdef ASSERT
2287 humongous_chunks->set_is_tagged_free(true);
2288 #endif
2289 if (TraceMetadataChunkAllocation && Verbose) {
2290 gclog_or_tty->print(PTR_FORMAT " (" SIZE_FORMAT ") ",
2291 p2i(humongous_chunks),
2292 humongous_chunks->word_size());
2293 }
2294 assert(humongous_chunks->word_size() == (size_t)
2295 align_size_up(humongous_chunks->word_size(),
2296 smallest_chunk_size()),
2297 err_msg("Humongous chunk size is wrong: word size " SIZE_FORMAT
2298 " granularity " SIZE_FORMAT,
2299 humongous_chunks->word_size(), smallest_chunk_size()));
2300 Metachunk* next_humongous_chunks = humongous_chunks->next();
2301 humongous_chunks->container()->dec_container_count();
2302 chunk_manager()->humongous_dictionary()->return_chunk(humongous_chunks);
2303 humongous_chunks = next_humongous_chunks;
2304 }
2305 if (TraceMetadataChunkAllocation && Verbose) {
2306 gclog_or_tty->cr();
2307 gclog_or_tty->print_cr("updated dictionary count " SIZE_FORMAT " %s",
2308 chunk_manager()->humongous_dictionary()->total_count(),
2309 chunk_size_name(HumongousIndex));
2310 }
2311 chunk_manager()->slow_locked_verify();
2312 }
2313
2314 const char* SpaceManager::chunk_size_name(ChunkIndex index) const {
2315 switch (index) {
2316 case SpecializedIndex:
2317 return "Specialized";
2318 case SmallIndex:
2319 return "Small";
2320 case MediumIndex:
2321 return "Medium";
2322 case HumongousIndex:
2323 return "Humongous";
2324 default:
2325 return NULL;
2326 }
2327 }
2328
2329 ChunkIndex ChunkManager::list_index(size_t size) {
2330 switch (size) {
2331 case SpecializedChunk:
2332 assert(SpecializedChunk == ClassSpecializedChunk,
2333 "Need branch for ClassSpecializedChunk");
2334 return SpecializedIndex;
2335 case SmallChunk:
2336 case ClassSmallChunk:
2337 return SmallIndex;
2338 case MediumChunk:
2339 case ClassMediumChunk:
2340 return MediumIndex;
2341 default:
2342 assert(size > MediumChunk || size > ClassMediumChunk,
2343 "Not a humongous chunk");
2344 return HumongousIndex;
2345 }
2346 }
2347
2348 void SpaceManager::deallocate(MetaWord* p, size_t word_size) {
2349 assert_lock_strong(_lock);
2350 size_t raw_word_size = get_raw_word_size(word_size);
2351 size_t min_size = TreeChunk<Metablock, FreeList<Metablock> >::min_size();
2352 assert(raw_word_size >= min_size,
2353 err_msg("Should not deallocate dark matter " SIZE_FORMAT "<" SIZE_FORMAT, word_size, min_size));
2354 block_freelists()->return_block(p, raw_word_size);
2355 }
2356
2357 // Adds a chunk to the list of chunks in use.
2358 void SpaceManager::add_chunk(Metachunk* new_chunk, bool make_current) {
2359
2360 assert(new_chunk != NULL, "Should not be NULL");
2361 assert(new_chunk->next() == NULL, "Should not be on a list");
2362
2363 new_chunk->reset_empty();
2364
2365 // Find the correct list and and set the current
2366 // chunk for that list.
2367 ChunkIndex index = ChunkManager::list_index(new_chunk->word_size());
2368
2369 if (index != HumongousIndex) {
2370 retire_current_chunk();
2371 set_current_chunk(new_chunk);
2372 new_chunk->set_next(chunks_in_use(index));
2373 set_chunks_in_use(index, new_chunk);
2374 } else {
2375 // For null class loader data and DumpSharedSpaces, the first chunk isn't
2376 // small, so small will be null. Link this first chunk as the current
2377 // chunk.
2378 if (make_current) {
2379 // Set as the current chunk but otherwise treat as a humongous chunk.
2380 set_current_chunk(new_chunk);
2381 }
2382 // Link at head. The _current_chunk only points to a humongous chunk for
2383 // the null class loader metaspace (class and data virtual space managers)
2384 // any humongous chunks so will not point to the tail
2385 // of the humongous chunks list.
2386 new_chunk->set_next(chunks_in_use(HumongousIndex));
2387 set_chunks_in_use(HumongousIndex, new_chunk);
2388
2389 assert(new_chunk->word_size() > medium_chunk_size(), "List inconsistency");
2390 }
2391
2392 // Add to the running sum of capacity
2393 inc_size_metrics(new_chunk->word_size());
2394
2395 assert(new_chunk->is_empty(), "Not ready for reuse");
2396 if (TraceMetadataChunkAllocation && Verbose) {
2397 gclog_or_tty->print("SpaceManager::add_chunk: " SIZE_FORMAT ") ",
2398 sum_count_in_chunks_in_use());
2399 new_chunk->print_on(gclog_or_tty);
2400 chunk_manager()->locked_print_free_chunks(gclog_or_tty);
2401 }
2402 }
2403
2404 void SpaceManager::retire_current_chunk() {
2405 if (current_chunk() != NULL) {
2406 size_t remaining_words = current_chunk()->free_word_size();
2407 if (remaining_words >= TreeChunk<Metablock, FreeList<Metablock> >::min_size()) {
2408 block_freelists()->return_block(current_chunk()->allocate(remaining_words), remaining_words);
2409 inc_used_metrics(remaining_words);
2410 }
2411 }
2412 }
2413
2414 Metachunk* SpaceManager::get_new_chunk(size_t word_size,
2415 size_t grow_chunks_by_words) {
2416 // Get a chunk from the chunk freelist
2417 Metachunk* next = chunk_manager()->chunk_freelist_allocate(grow_chunks_by_words);
2418
2419 if (next == NULL) {
2420 next = vs_list()->get_new_chunk(word_size,
2421 grow_chunks_by_words,
2422 medium_chunk_bunch());
2423 }
2424
2425 if (TraceMetadataHumongousAllocation && next != NULL &&
2426 SpaceManager::is_humongous(next->word_size())) {
2427 gclog_or_tty->print_cr(" new humongous chunk word size "
2428 PTR_FORMAT, next->word_size());
2429 }
2430
2431 return next;
2432 }
2433
2434 MetaWord* SpaceManager::allocate(size_t word_size) {
2435 MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag);
2436
2437 size_t raw_word_size = get_raw_word_size(word_size);
2438 BlockFreelist* fl = block_freelists();
2439 MetaWord* p = NULL;
2440 // Allocation from the dictionary is expensive in the sense that
2441 // the dictionary has to be searched for a size. Don't allocate
2442 // from the dictionary until it starts to get fat. Is this
2443 // a reasonable policy? Maybe an skinny dictionary is fast enough
2444 // for allocations. Do some profiling. JJJ
2445 if (fl->total_size() > allocation_from_dictionary_limit) {
2446 p = fl->get_block(raw_word_size);
2447 }
2448 if (p == NULL) {
2449 p = allocate_work(raw_word_size);
2450 }
2451
2452 return p;
2453 }
2454
2455 // Returns the address of spaced allocated for "word_size".
2456 // This methods does not know about blocks (Metablocks)
2457 MetaWord* SpaceManager::allocate_work(size_t word_size) {
2458 assert_lock_strong(_lock);
2459 #ifdef ASSERT
2460 if (Metadebug::test_metadata_failure()) {
2461 return NULL;
2462 }
2463 #endif
2464 // Is there space in the current chunk?
2465 MetaWord* result = NULL;
2466
2467 // For DumpSharedSpaces, only allocate out of the current chunk which is
2468 // never null because we gave it the size we wanted. Caller reports out
2469 // of memory if this returns null.
2470 if (DumpSharedSpaces) {
2471 assert(current_chunk() != NULL, "should never happen");
2472 inc_used_metrics(word_size);
2473 return current_chunk()->allocate(word_size); // caller handles null result
2474 }
2475
2476 if (current_chunk() != NULL) {
2477 result = current_chunk()->allocate(word_size);
2478 }
2479
2480 if (result == NULL) {
2481 result = grow_and_allocate(word_size);
2482 }
2483
2484 if (result != NULL) {
2485 inc_used_metrics(word_size);
2486 assert(result != (MetaWord*) chunks_in_use(MediumIndex),
2487 "Head of the list is being allocated");
2488 }
2489
2490 return result;
2491 }
2492
2493 void SpaceManager::verify() {
2494 // If there are blocks in the dictionary, then
2495 // verification of chunks does not work since
2496 // being in the dictionary alters a chunk.
2497 if (block_freelists()->total_size() == 0) {
2498 for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) {
2499 Metachunk* curr = chunks_in_use(i);
2500 while (curr != NULL) {
2501 curr->verify();
2502 verify_chunk_size(curr);
2503 curr = curr->next();
2504 }
2505 }
2506 }
2507 }
2508
2509 void SpaceManager::verify_chunk_size(Metachunk* chunk) {
2510 assert(is_humongous(chunk->word_size()) ||
2511 chunk->word_size() == medium_chunk_size() ||
2512 chunk->word_size() == small_chunk_size() ||
2513 chunk->word_size() == specialized_chunk_size(),
2514 "Chunk size is wrong");
2515 return;
2516 }
2517
2518 #ifdef ASSERT
2519 void SpaceManager::verify_allocated_blocks_words() {
2520 // Verification is only guaranteed at a safepoint.
2521 assert(SafepointSynchronize::is_at_safepoint() || !Universe::is_fully_initialized(),
2522 "Verification can fail if the applications is running");
2523 assert(allocated_blocks_words() == sum_used_in_chunks_in_use(),
2524 err_msg("allocation total is not consistent " SIZE_FORMAT
2525 " vs " SIZE_FORMAT,
2526 allocated_blocks_words(), sum_used_in_chunks_in_use()));
2527 }
2528
2529 #endif
2530
2531 void SpaceManager::dump(outputStream* const out) const {
2532 size_t curr_total = 0;
2533 size_t waste = 0;
2534 uint i = 0;
2535 size_t used = 0;
2536 size_t capacity = 0;
2537
2538 // Add up statistics for all chunks in this SpaceManager.
2539 for (ChunkIndex index = ZeroIndex;
2540 index < NumberOfInUseLists;
2541 index = next_chunk_index(index)) {
2542 for (Metachunk* curr = chunks_in_use(index);
2543 curr != NULL;
2544 curr = curr->next()) {
2545 out->print("%d) ", i++);
2546 curr->print_on(out);
2547 curr_total += curr->word_size();
2548 used += curr->used_word_size();
2549 capacity += curr->word_size();
2550 waste += curr->free_word_size() + curr->overhead();;
2551 }
2552 }
2553
2554 if (TraceMetadataChunkAllocation && Verbose) {
2555 block_freelists()->print_on(out);
2556 }
2557
2558 size_t free = current_chunk() == NULL ? 0 : current_chunk()->free_word_size();
2559 // Free space isn't wasted.
2560 waste -= free;
2561
2562 out->print_cr("total of all chunks " SIZE_FORMAT " used " SIZE_FORMAT
2563 " free " SIZE_FORMAT " capacity " SIZE_FORMAT
2564 " waste " SIZE_FORMAT, curr_total, used, free, capacity, waste);
2565 }
2566
2567 #ifndef PRODUCT
2568 void SpaceManager::mangle_freed_chunks() {
2569 for (ChunkIndex index = ZeroIndex;
2570 index < NumberOfInUseLists;
2571 index = next_chunk_index(index)) {
2572 for (Metachunk* curr = chunks_in_use(index);
2573 curr != NULL;
2574 curr = curr->next()) {
2575 curr->mangle();
2576 }
2577 }
2578 }
2579 #endif // PRODUCT
2580
2581 // MetaspaceAux
2582
2583
2584 size_t MetaspaceAux::_capacity_words[] = {0, 0};
2585 size_t MetaspaceAux::_used_words[] = {0, 0};
2586
2587 size_t MetaspaceAux::free_bytes(Metaspace::MetadataType mdtype) {
2588 VirtualSpaceList* list = Metaspace::get_space_list(mdtype);
2589 return list == NULL ? 0 : list->free_bytes();
2590 }
2591
2592 size_t MetaspaceAux::free_bytes() {
2593 return free_bytes(Metaspace::ClassType) + free_bytes(Metaspace::NonClassType);
2594 }
2595
2596 void MetaspaceAux::dec_capacity(Metaspace::MetadataType mdtype, size_t words) {
2597 assert_lock_strong(SpaceManager::expand_lock());
2598 assert(words <= capacity_words(mdtype),
2599 err_msg("About to decrement below 0: words " SIZE_FORMAT
2600 " is greater than _capacity_words[%u] " SIZE_FORMAT,
2601 words, mdtype, capacity_words(mdtype)));
2602 _capacity_words[mdtype] -= words;
2603 }
2604
2605 void MetaspaceAux::inc_capacity(Metaspace::MetadataType mdtype, size_t words) {
2606 assert_lock_strong(SpaceManager::expand_lock());
2607 // Needs to be atomic
2608 _capacity_words[mdtype] += words;
2609 }
2610
2611 void MetaspaceAux::dec_used(Metaspace::MetadataType mdtype, size_t words) {
2612 assert(words <= used_words(mdtype),
2613 err_msg("About to decrement below 0: words " SIZE_FORMAT
2614 " is greater than _used_words[%u] " SIZE_FORMAT,
2615 words, mdtype, used_words(mdtype)));
2616 // For CMS deallocation of the Metaspaces occurs during the
2617 // sweep which is a concurrent phase. Protection by the expand_lock()
2618 // is not enough since allocation is on a per Metaspace basis
2619 // and protected by the Metaspace lock.
2620 jlong minus_words = (jlong) - (jlong) words;
2621 Atomic::add_ptr(minus_words, &_used_words[mdtype]);
2622 }
2623
2624 void MetaspaceAux::inc_used(Metaspace::MetadataType mdtype, size_t words) {
2625 // _used_words tracks allocations for
2626 // each piece of metadata. Those allocations are
2627 // generally done concurrently by different application
2628 // threads so must be done atomically.
2629 Atomic::add_ptr(words, &_used_words[mdtype]);
2630 }
2631
2632 size_t MetaspaceAux::used_bytes_slow(Metaspace::MetadataType mdtype) {
2633 size_t used = 0;
2634 ClassLoaderDataGraphMetaspaceIterator iter;
2635 while (iter.repeat()) {
2636 Metaspace* msp = iter.get_next();
2637 // Sum allocated_blocks_words for each metaspace
2638 if (msp != NULL) {
2639 used += msp->used_words_slow(mdtype);
2640 }
2641 }
2642 return used * BytesPerWord;
2643 }
2644
2645 size_t MetaspaceAux::free_bytes_slow(Metaspace::MetadataType mdtype) {
2646 size_t free = 0;
2647 ClassLoaderDataGraphMetaspaceIterator iter;
2648 while (iter.repeat()) {
2649 Metaspace* msp = iter.get_next();
2650 if (msp != NULL) {
2651 free += msp->free_words_slow(mdtype);
2652 }
2653 }
2654 return free * BytesPerWord;
2655 }
2656
2657 size_t MetaspaceAux::capacity_bytes_slow(Metaspace::MetadataType mdtype) {
2658 if ((mdtype == Metaspace::ClassType) && !Metaspace::using_class_space()) {
2659 return 0;
2660 }
2661 // Don't count the space in the freelists. That space will be
2662 // added to the capacity calculation as needed.
2663 size_t capacity = 0;
2664 ClassLoaderDataGraphMetaspaceIterator iter;
2665 while (iter.repeat()) {
2666 Metaspace* msp = iter.get_next();
2667 if (msp != NULL) {
2668 capacity += msp->capacity_words_slow(mdtype);
2669 }
2670 }
2671 return capacity * BytesPerWord;
2672 }
2673
2674 size_t MetaspaceAux::capacity_bytes_slow() {
2675 #ifdef PRODUCT
2676 // Use capacity_bytes() in PRODUCT instead of this function.
2677 guarantee(false, "Should not call capacity_bytes_slow() in the PRODUCT");
2678 #endif
2679 size_t class_capacity = capacity_bytes_slow(Metaspace::ClassType);
2680 size_t non_class_capacity = capacity_bytes_slow(Metaspace::NonClassType);
2681 assert(capacity_bytes() == class_capacity + non_class_capacity,
2682 err_msg("bad accounting: capacity_bytes() " SIZE_FORMAT
2683 " class_capacity + non_class_capacity " SIZE_FORMAT
2684 " class_capacity " SIZE_FORMAT " non_class_capacity " SIZE_FORMAT,
2685 capacity_bytes(), class_capacity + non_class_capacity,
2686 class_capacity, non_class_capacity));
2687
2688 return class_capacity + non_class_capacity;
2689 }
2690
2691 size_t MetaspaceAux::reserved_bytes(Metaspace::MetadataType mdtype) {
2692 VirtualSpaceList* list = Metaspace::get_space_list(mdtype);
2693 return list == NULL ? 0 : list->reserved_bytes();
2694 }
2695
2696 size_t MetaspaceAux::committed_bytes(Metaspace::MetadataType mdtype) {
2697 VirtualSpaceList* list = Metaspace::get_space_list(mdtype);
2698 return list == NULL ? 0 : list->committed_bytes();
2699 }
2700
2701 size_t MetaspaceAux::min_chunk_size_words() { return Metaspace::first_chunk_word_size(); }
2702
2703 size_t MetaspaceAux::free_chunks_total_words(Metaspace::MetadataType mdtype) {
2704 ChunkManager* chunk_manager = Metaspace::get_chunk_manager(mdtype);
2705 if (chunk_manager == NULL) {
2706 return 0;
2707 }
2708 chunk_manager->slow_verify();
2709 return chunk_manager->free_chunks_total_words();
2710 }
2711
2712 size_t MetaspaceAux::free_chunks_total_bytes(Metaspace::MetadataType mdtype) {
2713 return free_chunks_total_words(mdtype) * BytesPerWord;
2714 }
2715
2716 size_t MetaspaceAux::free_chunks_total_words() {
2717 return free_chunks_total_words(Metaspace::ClassType) +
2718 free_chunks_total_words(Metaspace::NonClassType);
2719 }
2720
2721 size_t MetaspaceAux::free_chunks_total_bytes() {
2722 return free_chunks_total_words() * BytesPerWord;
2723 }
2724
2725 bool MetaspaceAux::has_chunk_free_list(Metaspace::MetadataType mdtype) {
2726 return Metaspace::get_chunk_manager(mdtype) != NULL;
2727 }
2728
2729 MetaspaceChunkFreeListSummary MetaspaceAux::chunk_free_list_summary(Metaspace::MetadataType mdtype) {
2730 if (!has_chunk_free_list(mdtype)) {
2731 return MetaspaceChunkFreeListSummary();
2732 }
2733
2734 const ChunkManager* cm = Metaspace::get_chunk_manager(mdtype);
2735 return cm->chunk_free_list_summary();
2736 }
2737
2738 void MetaspaceAux::print_metaspace_change(size_t prev_metadata_used) {
2739 gclog_or_tty->print(", [Metaspace:");
2740 if (PrintGCDetails && Verbose) {
2741 gclog_or_tty->print(" " SIZE_FORMAT
2742 "->" SIZE_FORMAT
2743 "(" SIZE_FORMAT ")",
2744 prev_metadata_used,
2745 used_bytes(),
2746 reserved_bytes());
2747 } else {
2748 gclog_or_tty->print(" " SIZE_FORMAT "K"
2749 "->" SIZE_FORMAT "K"
2750 "(" SIZE_FORMAT "K)",
2751 prev_metadata_used/K,
2752 used_bytes()/K,
2753 reserved_bytes()/K);
2754 }
2755
2756 gclog_or_tty->print("]");
2757 }
2758
2759 // This is printed when PrintGCDetails
2760 void MetaspaceAux::print_on(outputStream* out) {
2761 Metaspace::MetadataType nct = Metaspace::NonClassType;
2762
2763 out->print_cr(" Metaspace "
2764 "used " SIZE_FORMAT "K, "
2765 "capacity " SIZE_FORMAT "K, "
2766 "committed " SIZE_FORMAT "K, "
2767 "reserved " SIZE_FORMAT "K",
2768 used_bytes()/K,
2769 capacity_bytes()/K,
2770 committed_bytes()/K,
2771 reserved_bytes()/K);
2772
2773 if (Metaspace::using_class_space()) {
2774 Metaspace::MetadataType ct = Metaspace::ClassType;
2775 out->print_cr(" class space "
2776 "used " SIZE_FORMAT "K, "
2777 "capacity " SIZE_FORMAT "K, "
2778 "committed " SIZE_FORMAT "K, "
2779 "reserved " SIZE_FORMAT "K",
2780 used_bytes(ct)/K,
2781 capacity_bytes(ct)/K,
2782 committed_bytes(ct)/K,
2783 reserved_bytes(ct)/K);
2784 }
2785 }
2786
2787 // Print information for class space and data space separately.
2788 // This is almost the same as above.
2789 void MetaspaceAux::print_on(outputStream* out, Metaspace::MetadataType mdtype) {
2790 size_t free_chunks_capacity_bytes = free_chunks_total_bytes(mdtype);
2791 size_t capacity_bytes = capacity_bytes_slow(mdtype);
2792 size_t used_bytes = used_bytes_slow(mdtype);
2793 size_t free_bytes = free_bytes_slow(mdtype);
2794 size_t used_and_free = used_bytes + free_bytes +
2795 free_chunks_capacity_bytes;
2796 out->print_cr(" Chunk accounting: used in chunks " SIZE_FORMAT
2797 "K + unused in chunks " SIZE_FORMAT "K + "
2798 " capacity in free chunks " SIZE_FORMAT "K = " SIZE_FORMAT
2799 "K capacity in allocated chunks " SIZE_FORMAT "K",
2800 used_bytes / K,
2801 free_bytes / K,
2802 free_chunks_capacity_bytes / K,
2803 used_and_free / K,
2804 capacity_bytes / K);
2805 // Accounting can only be correct if we got the values during a safepoint
2806 assert(!SafepointSynchronize::is_at_safepoint() || used_and_free == capacity_bytes, "Accounting is wrong");
2807 }
2808
2809 // Print total fragmentation for class metaspaces
2810 void MetaspaceAux::print_class_waste(outputStream* out) {
2811 assert(Metaspace::using_class_space(), "class metaspace not used");
2812 size_t cls_specialized_waste = 0, cls_small_waste = 0, cls_medium_waste = 0;
2813 size_t cls_specialized_count = 0, cls_small_count = 0, cls_medium_count = 0, cls_humongous_count = 0;
2814 ClassLoaderDataGraphMetaspaceIterator iter;
2815 while (iter.repeat()) {
2816 Metaspace* msp = iter.get_next();
2817 if (msp != NULL) {
2818 cls_specialized_waste += msp->class_vsm()->sum_waste_in_chunks_in_use(SpecializedIndex);
2819 cls_specialized_count += msp->class_vsm()->sum_count_in_chunks_in_use(SpecializedIndex);
2820 cls_small_waste += msp->class_vsm()->sum_waste_in_chunks_in_use(SmallIndex);
2821 cls_small_count += msp->class_vsm()->sum_count_in_chunks_in_use(SmallIndex);
2822 cls_medium_waste += msp->class_vsm()->sum_waste_in_chunks_in_use(MediumIndex);
2823 cls_medium_count += msp->class_vsm()->sum_count_in_chunks_in_use(MediumIndex);
2824 cls_humongous_count += msp->class_vsm()->sum_count_in_chunks_in_use(HumongousIndex);
2825 }
2826 }
2827 out->print_cr(" class: " SIZE_FORMAT " specialized(s) " SIZE_FORMAT ", "
2828 SIZE_FORMAT " small(s) " SIZE_FORMAT ", "
2829 SIZE_FORMAT " medium(s) " SIZE_FORMAT ", "
2830 "large count " SIZE_FORMAT,
2831 cls_specialized_count, cls_specialized_waste,
2832 cls_small_count, cls_small_waste,
2833 cls_medium_count, cls_medium_waste, cls_humongous_count);
2834 }
2835
2836 // Print total fragmentation for data and class metaspaces separately
2837 void MetaspaceAux::print_waste(outputStream* out) {
2838 size_t specialized_waste = 0, small_waste = 0, medium_waste = 0;
2839 size_t specialized_count = 0, small_count = 0, medium_count = 0, humongous_count = 0;
2840
2841 ClassLoaderDataGraphMetaspaceIterator iter;
2842 while (iter.repeat()) {
2843 Metaspace* msp = iter.get_next();
2844 if (msp != NULL) {
2845 specialized_waste += msp->vsm()->sum_waste_in_chunks_in_use(SpecializedIndex);
2846 specialized_count += msp->vsm()->sum_count_in_chunks_in_use(SpecializedIndex);
2847 small_waste += msp->vsm()->sum_waste_in_chunks_in_use(SmallIndex);
2848 small_count += msp->vsm()->sum_count_in_chunks_in_use(SmallIndex);
2849 medium_waste += msp->vsm()->sum_waste_in_chunks_in_use(MediumIndex);
2850 medium_count += msp->vsm()->sum_count_in_chunks_in_use(MediumIndex);
2851 humongous_count += msp->vsm()->sum_count_in_chunks_in_use(HumongousIndex);
2852 }
2853 }
2854 out->print_cr("Total fragmentation waste (words) doesn't count free space");
2855 out->print_cr(" data: " SIZE_FORMAT " specialized(s) " SIZE_FORMAT ", "
2856 SIZE_FORMAT " small(s) " SIZE_FORMAT ", "
2857 SIZE_FORMAT " medium(s) " SIZE_FORMAT ", "
2858 "large count " SIZE_FORMAT,
2859 specialized_count, specialized_waste, small_count,
2860 small_waste, medium_count, medium_waste, humongous_count);
2861 if (Metaspace::using_class_space()) {
2862 print_class_waste(out);
2863 }
2864 }
2865
2866 // Dump global metaspace things from the end of ClassLoaderDataGraph
2867 void MetaspaceAux::dump(outputStream* out) {
2868 out->print_cr("All Metaspace:");
2869 out->print("data space: "); print_on(out, Metaspace::NonClassType);
2870 out->print("class space: "); print_on(out, Metaspace::ClassType);
2871 print_waste(out);
2872 }
2873
2874 void MetaspaceAux::verify_free_chunks() {
2875 Metaspace::chunk_manager_metadata()->verify();
2876 if (Metaspace::using_class_space()) {
2877 Metaspace::chunk_manager_class()->verify();
2878 }
2879 }
2880
2881 void MetaspaceAux::verify_capacity() {
2882 #ifdef ASSERT
2883 size_t running_sum_capacity_bytes = capacity_bytes();
2884 // For purposes of the running sum of capacity, verify against capacity
2885 size_t capacity_in_use_bytes = capacity_bytes_slow();
2886 assert(running_sum_capacity_bytes == capacity_in_use_bytes,
2887 err_msg("capacity_words() * BytesPerWord " SIZE_FORMAT
2888 " capacity_bytes_slow()" SIZE_FORMAT,
2889 running_sum_capacity_bytes, capacity_in_use_bytes));
2890 for (Metaspace::MetadataType i = Metaspace::ClassType;
2891 i < Metaspace:: MetadataTypeCount;
2892 i = (Metaspace::MetadataType)(i + 1)) {
2893 size_t capacity_in_use_bytes = capacity_bytes_slow(i);
2894 assert(capacity_bytes(i) == capacity_in_use_bytes,
2895 err_msg("capacity_bytes(%u) " SIZE_FORMAT
2896 " capacity_bytes_slow(%u)" SIZE_FORMAT,
2897 i, capacity_bytes(i), i, capacity_in_use_bytes));
2898 }
2899 #endif
2900 }
2901
2902 void MetaspaceAux::verify_used() {
2903 #ifdef ASSERT
2904 size_t running_sum_used_bytes = used_bytes();
2905 // For purposes of the running sum of used, verify against used
2906 size_t used_in_use_bytes = used_bytes_slow();
2907 assert(used_bytes() == used_in_use_bytes,
2908 err_msg("used_bytes() " SIZE_FORMAT
2909 " used_bytes_slow()" SIZE_FORMAT,
2910 used_bytes(), used_in_use_bytes));
2911 for (Metaspace::MetadataType i = Metaspace::ClassType;
2912 i < Metaspace:: MetadataTypeCount;
2913 i = (Metaspace::MetadataType)(i + 1)) {
2914 size_t used_in_use_bytes = used_bytes_slow(i);
2915 assert(used_bytes(i) == used_in_use_bytes,
2916 err_msg("used_bytes(%u) " SIZE_FORMAT
2917 " used_bytes_slow(%u)" SIZE_FORMAT,
2918 i, used_bytes(i), i, used_in_use_bytes));
2919 }
2920 #endif
2921 }
2922
2923 void MetaspaceAux::verify_metrics() {
2924 verify_capacity();
2925 verify_used();
2926 }
2927
2928
2929 // Metaspace methods
2930
2931 size_t Metaspace::_first_chunk_word_size = 0;
2932 size_t Metaspace::_first_class_chunk_word_size = 0;
2933
2934 size_t Metaspace::_commit_alignment = 0;
2935 size_t Metaspace::_reserve_alignment = 0;
2936
2937 Metaspace::Metaspace(Mutex* lock, MetaspaceType type) {
2938 initialize(lock, type);
2939 }
2940
2941 Metaspace::~Metaspace() {
2942 delete _vsm;
2943 if (using_class_space()) {
2944 delete _class_vsm;
2945 }
2946 }
2947
2948 VirtualSpaceList* Metaspace::_space_list = NULL;
2949 VirtualSpaceList* Metaspace::_class_space_list = NULL;
2950
2951 ChunkManager* Metaspace::_chunk_manager_metadata = NULL;
2952 ChunkManager* Metaspace::_chunk_manager_class = NULL;
2953
2954 #define VIRTUALSPACEMULTIPLIER 2
2955
2956 #ifdef _LP64
2957 static const uint64_t UnscaledClassSpaceMax = (uint64_t(max_juint) + 1);
2958
2959 void Metaspace::set_narrow_klass_base_and_shift(address metaspace_base, address cds_base) {
2960 // Figure out the narrow_klass_base and the narrow_klass_shift. The
2961 // narrow_klass_base is the lower of the metaspace base and the cds base
2962 // (if cds is enabled). The narrow_klass_shift depends on the distance
2963 // between the lower base and higher address.
2964 address lower_base;
2965 address higher_address;
2966 #if INCLUDE_CDS
2967 if (UseSharedSpaces) {
2968 higher_address = MAX2((address)(cds_base + FileMapInfo::shared_spaces_size()),
2969 (address)(metaspace_base + compressed_class_space_size()));
2970 lower_base = MIN2(metaspace_base, cds_base);
2971 } else
2972 #endif
2973 {
2974 higher_address = metaspace_base + compressed_class_space_size();
2975 lower_base = metaspace_base;
2976
2977 uint64_t klass_encoding_max = UnscaledClassSpaceMax << LogKlassAlignmentInBytes;
2978 // If compressed class space fits in lower 32G, we don't need a base.
2979 if (higher_address <= (address)klass_encoding_max) {
2980 lower_base = 0; // Effectively lower base is zero.
2981 }
2982 }
2983
2984 Universe::set_narrow_klass_base(lower_base);
2985
2986 if ((uint64_t)(higher_address - lower_base) <= UnscaledClassSpaceMax) {
2987 Universe::set_narrow_klass_shift(0);
2988 } else {
2989 assert(!UseSharedSpaces, "Cannot shift with UseSharedSpaces");
2990 Universe::set_narrow_klass_shift(LogKlassAlignmentInBytes);
2991 }
2992 }
2993
2994 #if INCLUDE_CDS
2995 // Return TRUE if the specified metaspace_base and cds_base are close enough
2996 // to work with compressed klass pointers.
2997 bool Metaspace::can_use_cds_with_metaspace_addr(char* metaspace_base, address cds_base) {
2998 assert(cds_base != 0 && UseSharedSpaces, "Only use with CDS");
2999 assert(UseCompressedClassPointers, "Only use with CompressedKlassPtrs");
3000 address lower_base = MIN2((address)metaspace_base, cds_base);
3001 address higher_address = MAX2((address)(cds_base + FileMapInfo::shared_spaces_size()),
3002 (address)(metaspace_base + compressed_class_space_size()));
3003 return ((uint64_t)(higher_address - lower_base) <= UnscaledClassSpaceMax);
3004 }
3005 #endif
3006
3007 // Try to allocate the metaspace at the requested addr.
3008 void Metaspace::allocate_metaspace_compressed_klass_ptrs(char* requested_addr, address cds_base) {
3009 assert(using_class_space(), "called improperly");
3010 assert(UseCompressedClassPointers, "Only use with CompressedKlassPtrs");
3011 assert(compressed_class_space_size() < KlassEncodingMetaspaceMax,
3012 "Metaspace size is too big");
3013 assert_is_ptr_aligned(requested_addr, _reserve_alignment);
3014 assert_is_ptr_aligned(cds_base, _reserve_alignment);
3015 assert_is_size_aligned(compressed_class_space_size(), _reserve_alignment);
3016
3017 // Don't use large pages for the class space.
3018 bool large_pages = false;
3019
3020 #ifndef AARCH64
3021 ReservedSpace metaspace_rs = ReservedSpace(compressed_class_space_size(),
3022 _reserve_alignment,
3023 large_pages,
3024 requested_addr);
3025 #else // AARCH64
3026 ReservedSpace metaspace_rs;
3027
3028 // Our compressed klass pointers may fit nicely into the lower 32
3029 // bits.
3030 if ((uint64_t)requested_addr + compressed_class_space_size() < 4*G) {
3031 metaspace_rs = ReservedSpace(compressed_class_space_size(),
3032 _reserve_alignment,
3033 large_pages,
3034 requested_addr);
3035 }
3036
3037 if (! metaspace_rs.is_reserved()) {
3038 // Try to align metaspace so that we can decode a compressed klass
3039 // with a single MOVK instruction. We can do this iff the
3040 // compressed class base is a multiple of 4G.
3041 for (char *a = (char*)align_ptr_up(requested_addr, 4*G);
3042 a < (char*)(1024*G);
3043 a += 4*G) {
3044
3045 #if INCLUDE_CDS
3046 if (UseSharedSpaces
3047 && ! can_use_cds_with_metaspace_addr(a, cds_base)) {
3048 // We failed to find an aligned base that will reach. Fall
3049 // back to using our requested addr.
3050 metaspace_rs = ReservedSpace(compressed_class_space_size(),
3051 _reserve_alignment,
3052 large_pages,
3053 requested_addr);
3054 break;
3055 }
3056 #endif
3057
3058 metaspace_rs = ReservedSpace(compressed_class_space_size(),
3059 _reserve_alignment,
3060 large_pages,
3061 a);
3062 if (metaspace_rs.is_reserved())
3063 break;
3064 }
3065 }
3066
3067 #endif // AARCH64
3068
3069 if (!metaspace_rs.is_reserved()) {
3070 #if INCLUDE_CDS
3071 if (UseSharedSpaces) {
3072 size_t increment = align_size_up(1*G, _reserve_alignment);
3073
3074 // Keep trying to allocate the metaspace, increasing the requested_addr
3075 // by 1GB each time, until we reach an address that will no longer allow
3076 // use of CDS with compressed klass pointers.
3077 char *addr = requested_addr;
3078 while (!metaspace_rs.is_reserved() && (addr + increment > addr) &&
3079 can_use_cds_with_metaspace_addr(addr + increment, cds_base)) {
3080 addr = addr + increment;
3081 metaspace_rs = ReservedSpace(compressed_class_space_size(),
3082 _reserve_alignment, large_pages, addr);
3083 }
3084 }
3085 #endif
3086 // If no successful allocation then try to allocate the space anywhere. If
3087 // that fails then OOM doom. At this point we cannot try allocating the
3088 // metaspace as if UseCompressedClassPointers is off because too much
3089 // initialization has happened that depends on UseCompressedClassPointers.
3090 // So, UseCompressedClassPointers cannot be turned off at this point.
3091 if (!metaspace_rs.is_reserved()) {
3092 metaspace_rs = ReservedSpace(compressed_class_space_size(),
3093 _reserve_alignment, large_pages);
3094 if (!metaspace_rs.is_reserved()) {
3095 vm_exit_during_initialization(err_msg("Could not allocate metaspace: " SIZE_FORMAT " bytes",
3096 compressed_class_space_size()));
3097 }
3098 }
3099 }
3100
3101 // If we got here then the metaspace got allocated.
3102 MemTracker::record_virtual_memory_type((address)metaspace_rs.base(), mtClass);
3103
3104 #if INCLUDE_CDS
3105 // Verify that we can use shared spaces. Otherwise, turn off CDS.
3106 if (UseSharedSpaces && !can_use_cds_with_metaspace_addr(metaspace_rs.base(), cds_base)) {
3107 FileMapInfo::stop_sharing_and_unmap(
3108 "Could not allocate metaspace at a compatible address");
3109 }
3110 #endif
3111 set_narrow_klass_base_and_shift((address)metaspace_rs.base(),
3112 UseSharedSpaces ? (address)cds_base : 0);
3113
3114 initialize_class_space(metaspace_rs);
3115
3116 if (PrintCompressedOopsMode || (PrintMiscellaneous && Verbose)) {
3117 gclog_or_tty->print_cr("Narrow klass base: " PTR_FORMAT ", Narrow klass shift: %d",
3118 p2i(Universe::narrow_klass_base()), Universe::narrow_klass_shift());
3119 gclog_or_tty->print_cr("Compressed class space size: " SIZE_FORMAT " Address: " PTR_FORMAT " Req Addr: " PTR_FORMAT,
3120 compressed_class_space_size(), p2i(metaspace_rs.base()), p2i(requested_addr));
3121 }
3122 }
3123
3124 // For UseCompressedClassPointers the class space is reserved above the top of
3125 // the Java heap. The argument passed in is at the base of the compressed space.
3126 void Metaspace::initialize_class_space(ReservedSpace rs) {
3127 // The reserved space size may be bigger because of alignment, esp with UseLargePages
3128 assert(rs.size() >= CompressedClassSpaceSize,
3129 err_msg(SIZE_FORMAT " != " SIZE_FORMAT, rs.size(), CompressedClassSpaceSize));
3130 assert(using_class_space(), "Must be using class space");
3131 _class_space_list = new VirtualSpaceList(rs);
3132 _chunk_manager_class = new ChunkManager(SpecializedChunk, ClassSmallChunk, ClassMediumChunk);
3133
3134 if (!_class_space_list->initialization_succeeded()) {
3135 vm_exit_during_initialization("Failed to setup compressed class space virtual space list.");
3136 }
3137 }
3138
3139 #endif
3140
3141 void Metaspace::ergo_initialize() {
3142 if (DumpSharedSpaces) {
3143 // Using large pages when dumping the shared archive is currently not implemented.
3144 FLAG_SET_ERGO(bool, UseLargePagesInMetaspace, false);
3145 }
3146
3147 size_t page_size = os::vm_page_size();
3148 if (UseLargePages && UseLargePagesInMetaspace) {
3149 page_size = os::large_page_size();
3150 }
3151
3152 _commit_alignment = page_size;
3153 _reserve_alignment = MAX2(page_size, (size_t)os::vm_allocation_granularity());
3154
3155 // Do not use FLAG_SET_ERGO to update MaxMetaspaceSize, since this will
3156 // override if MaxMetaspaceSize was set on the command line or not.
3157 // This information is needed later to conform to the specification of the
3158 // java.lang.management.MemoryUsage API.
3159 //
3160 // Ideally, we would be able to set the default value of MaxMetaspaceSize in
3161 // globals.hpp to the aligned value, but this is not possible, since the
3162 // alignment depends on other flags being parsed.
3163 MaxMetaspaceSize = align_size_down_bounded(MaxMetaspaceSize, _reserve_alignment);
3164
3165 if (MetaspaceSize > MaxMetaspaceSize) {
3166 MetaspaceSize = MaxMetaspaceSize;
3167 }
3168
3169 MetaspaceSize = align_size_down_bounded(MetaspaceSize, _commit_alignment);
3170
3171 assert(MetaspaceSize <= MaxMetaspaceSize, "MetaspaceSize should be limited by MaxMetaspaceSize");
3172
3173 if (MetaspaceSize < 256*K) {
3174 vm_exit_during_initialization("Too small initial Metaspace size");
3175 }
3176
3177 MinMetaspaceExpansion = align_size_down_bounded(MinMetaspaceExpansion, _commit_alignment);
3178 MaxMetaspaceExpansion = align_size_down_bounded(MaxMetaspaceExpansion, _commit_alignment);
3179
3180 CompressedClassSpaceSize = align_size_down_bounded(CompressedClassSpaceSize, _reserve_alignment);
3181 set_compressed_class_space_size(CompressedClassSpaceSize);
3182 }
3183
3184 void Metaspace::global_initialize() {
3185 MetaspaceGC::initialize();
3186
3187 // Initialize the alignment for shared spaces.
3188 int max_alignment = os::vm_allocation_granularity();
3189 size_t cds_total = 0;
3190
3191 MetaspaceShared::set_max_alignment(max_alignment);
3192
3193 if (DumpSharedSpaces) {
3194 #if INCLUDE_CDS
3195 MetaspaceShared::estimate_regions_size();
3196
3197 SharedReadOnlySize = align_size_up(SharedReadOnlySize, max_alignment);
3198 SharedReadWriteSize = align_size_up(SharedReadWriteSize, max_alignment);
3199 SharedMiscDataSize = align_size_up(SharedMiscDataSize, max_alignment);
3200 SharedMiscCodeSize = align_size_up(SharedMiscCodeSize, max_alignment);
3201
3202 // make sure SharedReadOnlySize and SharedReadWriteSize are not less than
3203 // the minimum values.
3204 if (SharedReadOnlySize < MetaspaceShared::min_ro_size){
3205 report_out_of_shared_space(SharedReadOnly);
3206 }
3207
3208 if (SharedReadWriteSize < MetaspaceShared::min_rw_size){
3209 report_out_of_shared_space(SharedReadWrite);
3210 }
3211
3212 // the min_misc_data_size and min_misc_code_size estimates are based on
3213 // MetaspaceShared::generate_vtable_methods().
3214 // The minimum size only accounts for the vtable methods. Any size less than the
3215 // minimum required size would cause vm crash when allocating the vtable methods.
3216 uint min_misc_data_size = align_size_up(
3217 MetaspaceShared::num_virtuals * MetaspaceShared::vtbl_list_size * sizeof(void*), max_alignment);
3218
3219 if (SharedMiscDataSize < min_misc_data_size) {
3220 report_out_of_shared_space(SharedMiscData);
3221 }
3222
3223 uintx min_misc_code_size = align_size_up(
3224 (MetaspaceShared::num_virtuals * MetaspaceShared::vtbl_list_size) *
3225 (sizeof(void*) + MetaspaceShared::vtbl_method_size) + MetaspaceShared::vtbl_common_code_size,
3226 max_alignment);
3227
3228 if (SharedMiscCodeSize < min_misc_code_size) {
3229 report_out_of_shared_space(SharedMiscCode);
3230 }
3231
3232 // Initialize with the sum of the shared space sizes. The read-only
3233 // and read write metaspace chunks will be allocated out of this and the
3234 // remainder is the misc code and data chunks.
3235 cds_total = FileMapInfo::shared_spaces_size();
3236 cds_total = align_size_up(cds_total, _reserve_alignment);
3237 _space_list = new VirtualSpaceList(cds_total/wordSize);
3238 _chunk_manager_metadata = new ChunkManager(SpecializedChunk, SmallChunk, MediumChunk);
3239
3240 if (!_space_list->initialization_succeeded()) {
3241 vm_exit_during_initialization("Unable to dump shared archive.", NULL);
3242 }
3243
3244 #ifdef _LP64
3245 if (cds_total + compressed_class_space_size() > UnscaledClassSpaceMax) {
3246 vm_exit_during_initialization("Unable to dump shared archive.",
3247 err_msg("Size of archive (" SIZE_FORMAT ") + compressed class space ("
3248 SIZE_FORMAT ") == total (" SIZE_FORMAT ") is larger than compressed "
3249 "klass limit: " UINT64_FORMAT, cds_total, compressed_class_space_size(),
3250 cds_total + compressed_class_space_size(), UnscaledClassSpaceMax));
3251 }
3252
3253 // Set the compressed klass pointer base so that decoding of these pointers works
3254 // properly when creating the shared archive.
3255 assert(UseCompressedOops && UseCompressedClassPointers,
3256 "UseCompressedOops and UseCompressedClassPointers must be set");
3257 Universe::set_narrow_klass_base((address)_space_list->current_virtual_space()->bottom());
3258 if (TraceMetavirtualspaceAllocation && Verbose) {
3259 gclog_or_tty->print_cr("Setting_narrow_klass_base to Address: " PTR_FORMAT,
3260 p2i(_space_list->current_virtual_space()->bottom()));
3261 }
3262
3263 Universe::set_narrow_klass_shift(0);
3264 #endif // _LP64
3265 #endif // INCLUDE_CDS
3266 } else {
3267 #if INCLUDE_CDS
3268 // If using shared space, open the file that contains the shared space
3269 // and map in the memory before initializing the rest of metaspace (so
3270 // the addresses don't conflict)
3271 address cds_address = NULL;
3272 if (UseSharedSpaces) {
3273 FileMapInfo* mapinfo = new FileMapInfo();
3274
3275 // Open the shared archive file, read and validate the header. If
3276 // initialization fails, shared spaces [UseSharedSpaces] are
3277 // disabled and the file is closed.
3278 // Map in spaces now also
3279 if (mapinfo->initialize() && MetaspaceShared::map_shared_spaces(mapinfo)) {
3280 cds_total = FileMapInfo::shared_spaces_size();
3281 cds_address = (address)mapinfo->region_base(0);
3282 } else {
3283 assert(!mapinfo->is_open() && !UseSharedSpaces,
3284 "archive file not closed or shared spaces not disabled.");
3285 }
3286 }
3287 #endif // INCLUDE_CDS
3288 #ifdef _LP64
3289 // If UseCompressedClassPointers is set then allocate the metaspace area
3290 // above the heap and above the CDS area (if it exists).
3291 if (using_class_space()) {
3292 if (UseSharedSpaces) {
3293 #if INCLUDE_CDS
3294 char* cds_end = (char*)(cds_address + cds_total);
3295 cds_end = (char *)align_ptr_up(cds_end, _reserve_alignment);
3296 allocate_metaspace_compressed_klass_ptrs(cds_end, cds_address);
3297 #endif
3298 } else {
3299 char* base = (char*)align_ptr_up(Universe::heap()->reserved_region().end(), _reserve_alignment);
3300 allocate_metaspace_compressed_klass_ptrs(base, 0);
3301 }
3302 }
3303 #endif // _LP64
3304
3305 // Initialize these before initializing the VirtualSpaceList
3306 _first_chunk_word_size = InitialBootClassLoaderMetaspaceSize / BytesPerWord;
3307 _first_chunk_word_size = align_word_size_up(_first_chunk_word_size);
3308 // Make the first class chunk bigger than a medium chunk so it's not put
3309 // on the medium chunk list. The next chunk will be small and progress
3310 // from there. This size calculated by -version.
3311 _first_class_chunk_word_size = MIN2((size_t)MediumChunk*6,
3312 (CompressedClassSpaceSize/BytesPerWord)*2);
3313 _first_class_chunk_word_size = align_word_size_up(_first_class_chunk_word_size);
3314 // Arbitrarily set the initial virtual space to a multiple
3315 // of the boot class loader size.
3316 size_t word_size = VIRTUALSPACEMULTIPLIER * _first_chunk_word_size;
3317 word_size = align_size_up(word_size, Metaspace::reserve_alignment_words());
3318
3319 // Initialize the list of virtual spaces.
3320 _space_list = new VirtualSpaceList(word_size);
3321 _chunk_manager_metadata = new ChunkManager(SpecializedChunk, SmallChunk, MediumChunk);
3322
3323 if (!_space_list->initialization_succeeded()) {
3324 vm_exit_during_initialization("Unable to setup metadata virtual space list.", NULL);
3325 }
3326 }
3327
3328 _tracer = new MetaspaceTracer();
3329 }
3330
3331 void Metaspace::post_initialize() {
3332 MetaspaceGC::post_initialize();
3333 }
3334
3335 Metachunk* Metaspace::get_initialization_chunk(MetadataType mdtype,
3336 size_t chunk_word_size,
3337 size_t chunk_bunch) {
3338 // Get a chunk from the chunk freelist
3339 Metachunk* chunk = get_chunk_manager(mdtype)->chunk_freelist_allocate(chunk_word_size);
3340 if (chunk != NULL) {
3341 return chunk;
3342 }
3343
3344 return get_space_list(mdtype)->get_new_chunk(chunk_word_size, chunk_word_size, chunk_bunch);
3345 }
3346
3347 void Metaspace::initialize(Mutex* lock, MetaspaceType type) {
3348
3349 assert(space_list() != NULL,
3350 "Metadata VirtualSpaceList has not been initialized");
3351 assert(chunk_manager_metadata() != NULL,
3352 "Metadata ChunkManager has not been initialized");
3353
3354 _vsm = new SpaceManager(NonClassType, lock);
3355 if (_vsm == NULL) {
3356 return;
3357 }
3358 size_t word_size;
3359 size_t class_word_size;
3360 vsm()->get_initial_chunk_sizes(type, &word_size, &class_word_size);
3361
3362 if (using_class_space()) {
3363 assert(class_space_list() != NULL,
3364 "Class VirtualSpaceList has not been initialized");
3365 assert(chunk_manager_class() != NULL,
3366 "Class ChunkManager has not been initialized");
3367
3368 // Allocate SpaceManager for classes.
3369 _class_vsm = new SpaceManager(ClassType, lock);
3370 if (_class_vsm == NULL) {
3371 return;
3372 }
3373 }
3374
3375 MutexLockerEx cl(SpaceManager::expand_lock(), Mutex::_no_safepoint_check_flag);
3376
3377 // Allocate chunk for metadata objects
3378 Metachunk* new_chunk = get_initialization_chunk(NonClassType,
3379 word_size,
3380 vsm()->medium_chunk_bunch());
3381 // For dumping shared archive, report error if allocation has failed.
3382 if (DumpSharedSpaces && new_chunk == NULL) {
3383 report_insufficient_metaspace(MetaspaceAux::committed_bytes() + word_size * BytesPerWord);
3384 }
3385 assert(!DumpSharedSpaces || new_chunk != NULL, "should have enough space for both chunks");
3386 if (new_chunk != NULL) {
3387 // Add to this manager's list of chunks in use and current_chunk().
3388 vsm()->add_chunk(new_chunk, true);
3389 }
3390
3391 // Allocate chunk for class metadata objects
3392 if (using_class_space()) {
3393 Metachunk* class_chunk = get_initialization_chunk(ClassType,
3394 class_word_size,
3395 class_vsm()->medium_chunk_bunch());
3396 if (class_chunk != NULL) {
3397 class_vsm()->add_chunk(class_chunk, true);
3398 } else {
3399 // For dumping shared archive, report error if allocation has failed.
3400 if (DumpSharedSpaces) {
3401 report_insufficient_metaspace(MetaspaceAux::committed_bytes() + class_word_size * BytesPerWord);
3402 }
3403 }
3404 }
3405
3406 _alloc_record_head = NULL;
3407 _alloc_record_tail = NULL;
3408 }
3409
3410 size_t Metaspace::align_word_size_up(size_t word_size) {
3411 size_t byte_size = word_size * wordSize;
3412 return ReservedSpace::allocation_align_size_up(byte_size) / wordSize;
3413 }
3414
3415 MetaWord* Metaspace::allocate(size_t word_size, MetadataType mdtype) {
3416 // DumpSharedSpaces doesn't use class metadata area (yet)
3417 // Also, don't use class_vsm() unless UseCompressedClassPointers is true.
3418 if (is_class_space_allocation(mdtype)) {
3419 return class_vsm()->allocate(word_size);
3420 } else {
3421 return vsm()->allocate(word_size);
3422 }
3423 }
3424
3425 MetaWord* Metaspace::expand_and_allocate(size_t word_size, MetadataType mdtype) {
3426 size_t delta_bytes = MetaspaceGC::delta_capacity_until_GC(word_size * BytesPerWord);
3427 assert(delta_bytes > 0, "Must be");
3428
3429 size_t before = 0;
3430 size_t after = 0;
3431 MetaWord* res;
3432 bool incremented;
3433
3434 // Each thread increments the HWM at most once. Even if the thread fails to increment
3435 // the HWM, an allocation is still attempted. This is because another thread must then
3436 // have incremented the HWM and therefore the allocation might still succeed.
3437 do {
3438 incremented = MetaspaceGC::inc_capacity_until_GC(delta_bytes, &after, &before);
3439 res = allocate(word_size, mdtype);
3440 } while (!incremented && res == NULL);
3441
3442 if (incremented) {
3443 tracer()->report_gc_threshold(before, after,
3444 MetaspaceGCThresholdUpdater::ExpandAndAllocate);
3445 if (PrintGCDetails && Verbose) {
3446 gclog_or_tty->print_cr("Increase capacity to GC from " SIZE_FORMAT
3447 " to " SIZE_FORMAT, before, after);
3448 }
3449 }
3450
3451 return res;
3452 }
3453
3454 // Space allocated in the Metaspace. This may
3455 // be across several metadata virtual spaces.
3456 char* Metaspace::bottom() const {
3457 assert(DumpSharedSpaces, "only useful and valid for dumping shared spaces");
3458 return (char*)vsm()->current_chunk()->bottom();
3459 }
3460
3461 size_t Metaspace::used_words_slow(MetadataType mdtype) const {
3462 if (mdtype == ClassType) {
3463 return using_class_space() ? class_vsm()->sum_used_in_chunks_in_use() : 0;
3464 } else {
3465 return vsm()->sum_used_in_chunks_in_use(); // includes overhead!
3466 }
3467 }
3468
3469 size_t Metaspace::free_words_slow(MetadataType mdtype) const {
3470 if (mdtype == ClassType) {
3471 return using_class_space() ? class_vsm()->sum_free_in_chunks_in_use() : 0;
3472 } else {
3473 return vsm()->sum_free_in_chunks_in_use();
3474 }
3475 }
3476
3477 // Space capacity in the Metaspace. It includes
3478 // space in the list of chunks from which allocations
3479 // have been made. Don't include space in the global freelist and
3480 // in the space available in the dictionary which
3481 // is already counted in some chunk.
3482 size_t Metaspace::capacity_words_slow(MetadataType mdtype) const {
3483 if (mdtype == ClassType) {
3484 return using_class_space() ? class_vsm()->sum_capacity_in_chunks_in_use() : 0;
3485 } else {
3486 return vsm()->sum_capacity_in_chunks_in_use();
3487 }
3488 }
3489
3490 size_t Metaspace::used_bytes_slow(MetadataType mdtype) const {
3491 return used_words_slow(mdtype) * BytesPerWord;
3492 }
3493
3494 size_t Metaspace::capacity_bytes_slow(MetadataType mdtype) const {
3495 return capacity_words_slow(mdtype) * BytesPerWord;
3496 }
3497
3498 size_t Metaspace::allocated_blocks_bytes() const {
3499 return vsm()->allocated_blocks_bytes() +
3500 (using_class_space() ? class_vsm()->allocated_blocks_bytes() : 0);
3501 }
3502
3503 size_t Metaspace::allocated_chunks_bytes() const {
3504 return vsm()->allocated_chunks_bytes() +
3505 (using_class_space() ? class_vsm()->allocated_chunks_bytes() : 0);
3506 }
3507
3508 void Metaspace::deallocate(MetaWord* ptr, size_t word_size, bool is_class) {
3509 assert(!SafepointSynchronize::is_at_safepoint()
3510 || Thread::current()->is_VM_thread(), "should be the VM thread");
3511
3512 if (DumpSharedSpaces && PrintSharedSpaces) {
3513 record_deallocation(ptr, vsm()->get_raw_word_size(word_size));
3514 }
3515
3516 MutexLockerEx ml(vsm()->lock(), Mutex::_no_safepoint_check_flag);
3517
3518 if (word_size < TreeChunk<Metablock, FreeList<Metablock> >::min_size()) {
3519 // Dark matter. Too small for dictionary.
3520 #ifdef ASSERT
3521 Copy::fill_to_words((HeapWord*)ptr, word_size, 0xf5f5f5f5);
3522 #endif
3523 return;
3524 }
3525 if (is_class && using_class_space()) {
3526 class_vsm()->deallocate(ptr, word_size);
3527 } else {
3528 vsm()->deallocate(ptr, word_size);
3529 }
3530 }
3531
3532
3533 MetaWord* Metaspace::allocate(ClassLoaderData* loader_data, size_t word_size,
3534 bool read_only, MetaspaceObj::Type type, TRAPS) {
3535 if (HAS_PENDING_EXCEPTION) {
3536 assert(false, "Should not allocate with exception pending");
3537 return NULL; // caller does a CHECK_NULL too
3538 }
3539
3540 assert(loader_data != NULL, "Should never pass around a NULL loader_data. "
3541 "ClassLoaderData::the_null_class_loader_data() should have been used.");
3542
3543 // Allocate in metaspaces without taking out a lock, because it deadlocks
3544 // with the SymbolTable_lock. Dumping is single threaded for now. We'll have
3545 // to revisit this for application class data sharing.
3546 if (DumpSharedSpaces) {
3547 assert(type > MetaspaceObj::UnknownType && type < MetaspaceObj::_number_of_types, "sanity");
3548 Metaspace* space = read_only ? loader_data->ro_metaspace() : loader_data->rw_metaspace();
3549 MetaWord* result = space->allocate(word_size, NonClassType);
3550 if (result == NULL) {
3551 report_out_of_shared_space(read_only ? SharedReadOnly : SharedReadWrite);
3552 }
3553 if (PrintSharedSpaces) {
3554 space->record_allocation(result, type, space->vsm()->get_raw_word_size(word_size));
3555 }
3556
3557 // Zero initialize.
3558 Copy::fill_to_aligned_words((HeapWord*)result, word_size, 0);
3559
3560 return result;
3561 }
3562
3563 MetadataType mdtype = (type == MetaspaceObj::ClassType) ? ClassType : NonClassType;
3564
3565 // Try to allocate metadata.
3566 MetaWord* result = loader_data->metaspace_non_null()->allocate(word_size, mdtype);
3567
3568 if (result == NULL) {
3569 tracer()->report_metaspace_allocation_failure(loader_data, word_size, type, mdtype);
3570
3571 // Allocation failed.
3572 if (is_init_completed()) {
3573 // Only start a GC if the bootstrapping has completed.
3574
3575 // Try to clean out some memory and retry.
3576 result = Universe::heap()->collector_policy()->satisfy_failed_metadata_allocation(
3577 loader_data, word_size, mdtype);
3578 }
3579 }
3580
3581 if (result == NULL) {
3582 report_metadata_oome(loader_data, word_size, type, mdtype, CHECK_NULL);
3583 }
3584
3585 // Zero initialize.
3586 Copy::fill_to_aligned_words((HeapWord*)result, word_size, 0);
3587
3588 return result;
3589 }
3590
3591 size_t Metaspace::class_chunk_size(size_t word_size) {
3592 assert(using_class_space(), "Has to use class space");
3593 return class_vsm()->calc_chunk_size(word_size);
3594 }
3595
3596 void Metaspace::report_metadata_oome(ClassLoaderData* loader_data, size_t word_size, MetaspaceObj::Type type, MetadataType mdtype, TRAPS) {
3597 tracer()->report_metadata_oom(loader_data, word_size, type, mdtype);
3598
3599 // If result is still null, we are out of memory.
3600 if (Verbose && TraceMetadataChunkAllocation) {
3601 gclog_or_tty->print_cr("Metaspace allocation failed for size "
3602 SIZE_FORMAT, word_size);
3603 if (loader_data->metaspace_or_null() != NULL) {
3604 loader_data->dump(gclog_or_tty);
3605 }
3606 MetaspaceAux::dump(gclog_or_tty);
3607 }
3608
3609 bool out_of_compressed_class_space = false;
3610 if (is_class_space_allocation(mdtype)) {
3611 Metaspace* metaspace = loader_data->metaspace_non_null();
3612 out_of_compressed_class_space =
3613 MetaspaceAux::committed_bytes(Metaspace::ClassType) +
3614 (metaspace->class_chunk_size(word_size) * BytesPerWord) >
3615 CompressedClassSpaceSize;
3616 }
3617
3618 // -XX:+HeapDumpOnOutOfMemoryError and -XX:OnOutOfMemoryError support
3619 const char* space_string = out_of_compressed_class_space ?
3620 "Compressed class space" : "Metaspace";
3621
3622 report_java_out_of_memory(space_string);
3623
3624 if (JvmtiExport::should_post_resource_exhausted()) {
3625 JvmtiExport::post_resource_exhausted(
3626 JVMTI_RESOURCE_EXHAUSTED_OOM_ERROR,
3627 space_string);
3628 }
3629
3630 if (!is_init_completed()) {
3631 vm_exit_during_initialization("OutOfMemoryError", space_string);
3632 }
3633
3634 if (out_of_compressed_class_space) {
3635 THROW_OOP(Universe::out_of_memory_error_class_metaspace());
3636 } else {
3637 THROW_OOP(Universe::out_of_memory_error_metaspace());
3638 }
3639 }
3640
3641 const char* Metaspace::metadata_type_name(Metaspace::MetadataType mdtype) {
3642 switch (mdtype) {
3643 case Metaspace::ClassType: return "Class";
3644 case Metaspace::NonClassType: return "Metadata";
3645 default:
3646 assert(false, err_msg("Got bad mdtype: %d", (int) mdtype));
3647 return NULL;
3648 }
3649 }
3650
3651 void Metaspace::record_allocation(void* ptr, MetaspaceObj::Type type, size_t word_size) {
3652 assert(DumpSharedSpaces, "sanity");
3653
3654 int byte_size = (int)word_size * HeapWordSize;
3655 AllocRecord *rec = new AllocRecord((address)ptr, type, byte_size);
3656
3657 if (_alloc_record_head == NULL) {
3658 _alloc_record_head = _alloc_record_tail = rec;
3659 } else if (_alloc_record_tail->_ptr + _alloc_record_tail->_byte_size == (address)ptr) {
3660 _alloc_record_tail->_next = rec;
3661 _alloc_record_tail = rec;
3662 } else {
3663 // slow linear search, but this doesn't happen that often, and only when dumping
3664 for (AllocRecord *old = _alloc_record_head; old; old = old->_next) {
3665 if (old->_ptr == ptr) {
3666 assert(old->_type == MetaspaceObj::DeallocatedType, "sanity");
3667 int remain_bytes = old->_byte_size - byte_size;
3668 assert(remain_bytes >= 0, "sanity");
3669 old->_type = type;
3670
3671 if (remain_bytes == 0) {
3672 delete(rec);
3673 } else {
3674 address remain_ptr = address(ptr) + byte_size;
3675 rec->_ptr = remain_ptr;
3676 rec->_byte_size = remain_bytes;
3677 rec->_type = MetaspaceObj::DeallocatedType;
3678 rec->_next = old->_next;
3679 old->_byte_size = byte_size;
3680 old->_next = rec;
3681 }
3682 return;
3683 }
3684 }
3685 assert(0, "reallocating a freed pointer that was not recorded");
3686 }
3687 }
3688
3689 void Metaspace::record_deallocation(void* ptr, size_t word_size) {
3690 assert(DumpSharedSpaces, "sanity");
3691
3692 for (AllocRecord *rec = _alloc_record_head; rec; rec = rec->_next) {
3693 if (rec->_ptr == ptr) {
3694 assert(rec->_byte_size == (int)word_size * HeapWordSize, "sanity");
3695 rec->_type = MetaspaceObj::DeallocatedType;
3696 return;
3697 }
3698 }
3699
3700 assert(0, "deallocating a pointer that was not recorded");
3701 }
3702
3703 void Metaspace::iterate(Metaspace::AllocRecordClosure *closure) {
3704 assert(DumpSharedSpaces, "unimplemented for !DumpSharedSpaces");
3705
3706 address last_addr = (address)bottom();
3707
3708 for (AllocRecord *rec = _alloc_record_head; rec; rec = rec->_next) {
3709 address ptr = rec->_ptr;
3710 if (last_addr < ptr) {
3711 closure->doit(last_addr, MetaspaceObj::UnknownType, ptr - last_addr);
3712 }
3713 closure->doit(ptr, rec->_type, rec->_byte_size);
3714 last_addr = ptr + rec->_byte_size;
3715 }
3716
3717 address top = ((address)bottom()) + used_bytes_slow(Metaspace::NonClassType);
3718 if (last_addr < top) {
3719 closure->doit(last_addr, MetaspaceObj::UnknownType, top - last_addr);
3720 }
3721 }
3722
3723 void Metaspace::purge(MetadataType mdtype) {
3724 get_space_list(mdtype)->purge(get_chunk_manager(mdtype));
3725 }
3726
3727 void Metaspace::purge() {
3728 MutexLockerEx cl(SpaceManager::expand_lock(),
3729 Mutex::_no_safepoint_check_flag);
3730 purge(NonClassType);
3731 if (using_class_space()) {
3732 purge(ClassType);
3733 }
3734 }
3735
3736 void Metaspace::print_on(outputStream* out) const {
3737 // Print both class virtual space counts and metaspace.
3738 if (Verbose) {
3739 vsm()->print_on(out);
3740 if (using_class_space()) {
3741 class_vsm()->print_on(out);
3742 }
3743 }
3744 }
3745
3746 bool Metaspace::contains(const void* ptr) {
3747 if (UseSharedSpaces && MetaspaceShared::is_in_shared_space(ptr)) {
3748 return true;
3749 }
3750
3751 if (using_class_space() && get_space_list(ClassType)->contains(ptr)) {
3752 return true;
3753 }
3754
3755 return get_space_list(NonClassType)->contains(ptr);
3756 }
3757
3758 void Metaspace::verify() {
3759 vsm()->verify();
3760 if (using_class_space()) {
3761 class_vsm()->verify();
3762 }
3763 }
3764
3765 void Metaspace::dump(outputStream* const out) const {
3766 out->print_cr("\nVirtual space manager: " INTPTR_FORMAT, p2i(vsm()));
3767 vsm()->dump(out);
3768 if (using_class_space()) {
3769 out->print_cr("\nClass space manager: " INTPTR_FORMAT, p2i(class_vsm()));
3770 class_vsm()->dump(out);
3771 }
3772 }
3773
3774 /////////////// Unit tests ///////////////
3775
3776 #ifndef PRODUCT
3777
3778 class TestMetaspaceAuxTest : AllStatic {
3779 public:
3780 static void test_reserved() {
3781 size_t reserved = MetaspaceAux::reserved_bytes();
3782
3783 assert(reserved > 0, "assert");
3784
3785 size_t committed = MetaspaceAux::committed_bytes();
3786 assert(committed <= reserved, "assert");
3787
3788 size_t reserved_metadata = MetaspaceAux::reserved_bytes(Metaspace::NonClassType);
3789 assert(reserved_metadata > 0, "assert");
3790 assert(reserved_metadata <= reserved, "assert");
3791
3792 if (UseCompressedClassPointers) {
3793 size_t reserved_class = MetaspaceAux::reserved_bytes(Metaspace::ClassType);
3794 assert(reserved_class > 0, "assert");
3795 assert(reserved_class < reserved, "assert");
3796 }
3797 }
3798
3799 static void test_committed() {
3800 size_t committed = MetaspaceAux::committed_bytes();
3801
3802 assert(committed > 0, "assert");
3803
3804 size_t reserved = MetaspaceAux::reserved_bytes();
3805 assert(committed <= reserved, "assert");
3806
3807 size_t committed_metadata = MetaspaceAux::committed_bytes(Metaspace::NonClassType);
3808 assert(committed_metadata > 0, "assert");
3809 assert(committed_metadata <= committed, "assert");
3810
3811 if (UseCompressedClassPointers) {
3812 size_t committed_class = MetaspaceAux::committed_bytes(Metaspace::ClassType);
3813 assert(committed_class > 0, "assert");
3814 assert(committed_class < committed, "assert");
3815 }
3816 }
3817
3818 static void test_virtual_space_list_large_chunk() {
3819 VirtualSpaceList* vs_list = new VirtualSpaceList(os::vm_allocation_granularity());
3820 MutexLockerEx cl(SpaceManager::expand_lock(), Mutex::_no_safepoint_check_flag);
3821 // A size larger than VirtualSpaceSize (256k) and add one page to make it _not_ be
3822 // vm_allocation_granularity aligned on Windows.
3823 size_t large_size = (size_t)(2*256*K + (os::vm_page_size()/BytesPerWord));
3824 large_size += (os::vm_page_size()/BytesPerWord);
3825 vs_list->get_new_chunk(large_size, large_size, 0);
3826 }
3827
3828 static void test() {
3829 test_reserved();
3830 test_committed();
3831 test_virtual_space_list_large_chunk();
3832 }
3833 };
3834
3835 void TestMetaspaceAux_test() {
3836 TestMetaspaceAuxTest::test();
3837 }
3838
3839 class TestVirtualSpaceNodeTest {
3840 static void chunk_up(size_t words_left, size_t& num_medium_chunks,
3841 size_t& num_small_chunks,
3842 size_t& num_specialized_chunks) {
3843 num_medium_chunks = words_left / MediumChunk;
3844 words_left = words_left % MediumChunk;
3845
3846 num_small_chunks = words_left / SmallChunk;
3847 words_left = words_left % SmallChunk;
3848 // how many specialized chunks can we get?
3849 num_specialized_chunks = words_left / SpecializedChunk;
3850 assert(words_left % SpecializedChunk == 0, "should be nothing left");
3851 }
3852
3853 public:
3854 static void test() {
3855 MutexLockerEx ml(SpaceManager::expand_lock(), Mutex::_no_safepoint_check_flag);
3856 const size_t vsn_test_size_words = MediumChunk * 4;
3857 const size_t vsn_test_size_bytes = vsn_test_size_words * BytesPerWord;
3858
3859 // The chunk sizes must be multiples of eachother, or this will fail
3860 STATIC_ASSERT(MediumChunk % SmallChunk == 0);
3861 STATIC_ASSERT(SmallChunk % SpecializedChunk == 0);
3862
3863 { // No committed memory in VSN
3864 ChunkManager cm(SpecializedChunk, SmallChunk, MediumChunk);
3865 VirtualSpaceNode vsn(vsn_test_size_bytes);
3866 vsn.initialize();
3867 vsn.retire(&cm);
3868 assert(cm.sum_free_chunks_count() == 0, "did not commit any memory in the VSN");
3869 }
3870
3871 { // All of VSN is committed, half is used by chunks
3872 ChunkManager cm(SpecializedChunk, SmallChunk, MediumChunk);
3873 VirtualSpaceNode vsn(vsn_test_size_bytes);
3874 vsn.initialize();
3875 vsn.expand_by(vsn_test_size_words, vsn_test_size_words);
3876 vsn.get_chunk_vs(MediumChunk);
3877 vsn.get_chunk_vs(MediumChunk);
3878 vsn.retire(&cm);
3879 assert(cm.sum_free_chunks_count() == 2, "should have been memory left for 2 medium chunks");
3880 assert(cm.sum_free_chunks() == 2*MediumChunk, "sizes should add up");
3881 }
3882
3883 const size_t page_chunks = 4 * (size_t)os::vm_page_size() / BytesPerWord;
3884 // This doesn't work for systems with vm_page_size >= 16K.
3885 if (page_chunks < MediumChunk) {
3886 // 4 pages of VSN is committed, some is used by chunks
3887 ChunkManager cm(SpecializedChunk, SmallChunk, MediumChunk);
3888 VirtualSpaceNode vsn(vsn_test_size_bytes);
3889
3890 vsn.initialize();
3891 vsn.expand_by(page_chunks, page_chunks);
3892 vsn.get_chunk_vs(SmallChunk);
3893 vsn.get_chunk_vs(SpecializedChunk);
3894 vsn.retire(&cm);
3895
3896 // committed - used = words left to retire
3897 const size_t words_left = page_chunks - SmallChunk - SpecializedChunk;
3898
3899 size_t num_medium_chunks, num_small_chunks, num_spec_chunks;
3900 chunk_up(words_left, num_medium_chunks, num_small_chunks, num_spec_chunks);
3901
3902 assert(num_medium_chunks == 0, "should not get any medium chunks");
3903 assert(cm.sum_free_chunks_count() == (num_small_chunks + num_spec_chunks), "should be space for 3 chunks");
3904 assert(cm.sum_free_chunks() == words_left, "sizes should add up");
3905 }
3906
3907 { // Half of VSN is committed, a humongous chunk is used
3908 ChunkManager cm(SpecializedChunk, SmallChunk, MediumChunk);
3909 VirtualSpaceNode vsn(vsn_test_size_bytes);
3910 vsn.initialize();
3911 vsn.expand_by(MediumChunk * 2, MediumChunk * 2);
3912 vsn.get_chunk_vs(MediumChunk + SpecializedChunk); // Humongous chunks will be aligned up to MediumChunk + SpecializedChunk
3913 vsn.retire(&cm);
3914
3915 const size_t words_left = MediumChunk * 2 - (MediumChunk + SpecializedChunk);
3916 size_t num_medium_chunks, num_small_chunks, num_spec_chunks;
3917 chunk_up(words_left, num_medium_chunks, num_small_chunks, num_spec_chunks);
3918
3919 assert(num_medium_chunks == 0, "should not get any medium chunks");
3920 assert(cm.sum_free_chunks_count() == (num_small_chunks + num_spec_chunks), "should be space for 3 chunks");
3921 assert(cm.sum_free_chunks() == words_left, "sizes should add up");
3922 }
3923
3924 }
3925
3926 #define assert_is_available_positive(word_size) \
3927 assert(vsn.is_available(word_size), \
3928 err_msg(#word_size ": " PTR_FORMAT " bytes were not available in " \
3929 "VirtualSpaceNode [" PTR_FORMAT ", " PTR_FORMAT ")", \
3930 (uintptr_t)(word_size * BytesPerWord), p2i(vsn.bottom()), p2i(vsn.end())));
3931
3932 #define assert_is_available_negative(word_size) \
3933 assert(!vsn.is_available(word_size), \
3934 err_msg(#word_size ": " PTR_FORMAT " bytes should not be available in " \
3935 "VirtualSpaceNode [" PTR_FORMAT ", " PTR_FORMAT ")", \
3936 (uintptr_t)(word_size * BytesPerWord), p2i(vsn.bottom()), p2i(vsn.end())));
3937
3938 static void test_is_available_positive() {
3939 // Reserve some memory.
3940 VirtualSpaceNode vsn(os::vm_allocation_granularity());
3941 assert(vsn.initialize(), "Failed to setup VirtualSpaceNode");
3942
3943 // Commit some memory.
3944 size_t commit_word_size = os::vm_allocation_granularity() / BytesPerWord;
3945 bool expanded = vsn.expand_by(commit_word_size, commit_word_size);
3946 assert(expanded, "Failed to commit");
3947
3948 // Check that is_available accepts the committed size.
3949 assert_is_available_positive(commit_word_size);
3950
3951 // Check that is_available accepts half the committed size.
3952 size_t expand_word_size = commit_word_size / 2;
3953 assert_is_available_positive(expand_word_size);
3954 }
3955
3956 static void test_is_available_negative() {
3957 // Reserve some memory.
3958 VirtualSpaceNode vsn(os::vm_allocation_granularity());
3959 assert(vsn.initialize(), "Failed to setup VirtualSpaceNode");
3960
3961 // Commit some memory.
3962 size_t commit_word_size = os::vm_allocation_granularity() / BytesPerWord;
3963 bool expanded = vsn.expand_by(commit_word_size, commit_word_size);
3964 assert(expanded, "Failed to commit");
3965
3966 // Check that is_available doesn't accept a too large size.
3967 size_t two_times_commit_word_size = commit_word_size * 2;
3968 assert_is_available_negative(two_times_commit_word_size);
3969 }
3970
3971 static void test_is_available_overflow() {
3972 // Reserve some memory.
3973 VirtualSpaceNode vsn(os::vm_allocation_granularity());
3974 assert(vsn.initialize(), "Failed to setup VirtualSpaceNode");
3975
3976 // Commit some memory.
3977 size_t commit_word_size = os::vm_allocation_granularity() / BytesPerWord;
3978 bool expanded = vsn.expand_by(commit_word_size, commit_word_size);
3979 assert(expanded, "Failed to commit");
3980
3981 // Calculate a size that will overflow the virtual space size.
3982 void* virtual_space_max = (void*)(uintptr_t)-1;
3983 size_t bottom_to_max = pointer_delta(virtual_space_max, vsn.bottom(), 1);
3984 size_t overflow_size = bottom_to_max + BytesPerWord;
3985 size_t overflow_word_size = overflow_size / BytesPerWord;
3986
3987 // Check that is_available can handle the overflow.
3988 assert_is_available_negative(overflow_word_size);
3989 }
3990
3991 static void test_is_available() {
3992 TestVirtualSpaceNodeTest::test_is_available_positive();
3993 TestVirtualSpaceNodeTest::test_is_available_negative();
3994 TestVirtualSpaceNodeTest::test_is_available_overflow();
3995 }
3996 };
3997
3998 void TestVirtualSpaceNode_test() {
3999 TestVirtualSpaceNodeTest::test();
4000 TestVirtualSpaceNodeTest::test_is_available();
4001 }
4002 #endif