1 /*
2 * Copyright (c) 2011, 2013, 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/binaryTreeDictionary.hpp"
27 #include "memory/freeList.hpp"
28 #include "memory/collectorPolicy.hpp"
29 #include "memory/filemap.hpp"
30 #include "memory/freeList.hpp"
31 #include "memory/metablock.hpp"
32 #include "memory/metachunk.hpp"
33 #include "memory/metaspace.hpp"
34 #include "memory/metaspaceShared.hpp"
35 #include "memory/resourceArea.hpp"
36 #include "memory/universe.hpp"
37 #include "runtime/globals.hpp"
38 #include "runtime/java.hpp"
39 #include "runtime/mutex.hpp"
40 #include "runtime/orderAccess.hpp"
41 #include "services/memTracker.hpp"
42 #include "utilities/copy.hpp"
43 #include "utilities/debug.hpp"
44
45 typedef BinaryTreeDictionary<Metablock, FreeList> BlockTreeDictionary;
46 typedef BinaryTreeDictionary<Metachunk, FreeList> ChunkTreeDictionary;
47 // Define this macro to enable slow integrity checking of
48 // the free chunk lists
49 const bool metaspace_slow_verify = false;
50
51 // Parameters for stress mode testing
52 const uint metadata_deallocate_a_lot_block = 10;
53 const uint metadata_deallocate_a_lock_chunk = 3;
54 size_t const allocation_from_dictionary_limit = 4 * K;
55
56 MetaWord* last_allocated = 0;
57
58 size_t Metaspace::_class_metaspace_size;
59
60 // Used in declarations in SpaceManager and ChunkManager
61 enum ChunkIndex {
62 ZeroIndex = 0,
63 SpecializedIndex = ZeroIndex,
64 SmallIndex = SpecializedIndex + 1,
65 MediumIndex = SmallIndex + 1,
66 HumongousIndex = MediumIndex + 1,
67 NumberOfFreeLists = 3,
68 NumberOfInUseLists = 4
69 };
70
71 enum ChunkSizes { // in words.
72 ClassSpecializedChunk = 128,
73 SpecializedChunk = 128,
74 ClassSmallChunk = 256,
75 SmallChunk = 512,
76 ClassMediumChunk = 4 * K,
77 MediumChunk = 8 * K,
78 HumongousChunkGranularity = 8
79 };
80
81 static ChunkIndex next_chunk_index(ChunkIndex i) {
82 assert(i < NumberOfInUseLists, "Out of bound");
83 return (ChunkIndex) (i+1);
84 }
85
86 // Originally _capacity_until_GC was set to MetaspaceSize here but
87 // the default MetaspaceSize before argument processing was being
88 // used which was not the desired value. See the code
89 // in should_expand() to see how the initialization is handled
90 // now.
91 size_t MetaspaceGC::_capacity_until_GC = 0;
92 bool MetaspaceGC::_expand_after_GC = false;
93 uint MetaspaceGC::_shrink_factor = 0;
94 bool MetaspaceGC::_should_concurrent_collect = false;
95
96 // Blocks of space for metadata are allocated out of Metachunks.
97 //
98 // Metachunk are allocated out of MetadataVirtualspaces and once
99 // allocated there is no explicit link between a Metachunk and
100 // the MetadataVirtualspaces from which it was allocated.
101 //
102 // Each SpaceManager maintains a
103 // list of the chunks it is using and the current chunk. The current
104 // chunk is the chunk from which allocations are done. Space freed in
105 // a chunk is placed on the free list of blocks (BlockFreelist) and
106 // reused from there.
107
108 typedef class FreeList<Metachunk> ChunkList;
109
110 // Manages the global free lists of chunks.
111 // Has three lists of free chunks, and a total size and
112 // count that includes all three
113
114 class ChunkManager VALUE_OBJ_CLASS_SPEC {
115
116 // Free list of chunks of different sizes.
117 // SpecializedChunk
118 // SmallChunk
119 // MediumChunk
120 // HumongousChunk
121 ChunkList _free_chunks[NumberOfFreeLists];
122
123
124 // HumongousChunk
125 ChunkTreeDictionary _humongous_dictionary;
126
127 // ChunkManager in all lists of this type
128 size_t _free_chunks_total;
129 size_t _free_chunks_count;
130
131 void dec_free_chunks_total(size_t v) {
132 assert(_free_chunks_count > 0 &&
133 _free_chunks_total > 0,
134 "About to go negative");
135 Atomic::add_ptr(-1, &_free_chunks_count);
136 jlong minus_v = (jlong) - (jlong) v;
137 Atomic::add_ptr(minus_v, &_free_chunks_total);
138 }
139
140 // Debug support
141
142 size_t sum_free_chunks();
143 size_t sum_free_chunks_count();
144
145 void locked_verify_free_chunks_total();
146 void slow_locked_verify_free_chunks_total() {
147 if (metaspace_slow_verify) {
148 locked_verify_free_chunks_total();
149 }
150 }
151 void locked_verify_free_chunks_count();
152 void slow_locked_verify_free_chunks_count() {
153 if (metaspace_slow_verify) {
154 locked_verify_free_chunks_count();
155 }
156 }
157 void verify_free_chunks_count();
158
159 public:
160
161 ChunkManager() : _free_chunks_total(0), _free_chunks_count(0) {}
162
163 // add or delete (return) a chunk to the global freelist.
164 Metachunk* chunk_freelist_allocate(size_t word_size);
165 void chunk_freelist_deallocate(Metachunk* chunk);
166
167 // Map a size to a list index assuming that there are lists
168 // for special, small, medium, and humongous chunks.
169 static ChunkIndex list_index(size_t size);
170
171 // Remove the chunk from its freelist. It is
172 // expected to be on one of the _free_chunks[] lists.
173 void remove_chunk(Metachunk* chunk);
174
175 // Add the simple linked list of chunks to the freelist of chunks
176 // of type index.
177 void return_chunks(ChunkIndex index, Metachunk* chunks);
178
179 // Total of the space in the free chunks list
180 size_t free_chunks_total_words();
181 size_t free_chunks_total_bytes();
182
183 // Number of chunks in the free chunks list
184 size_t free_chunks_count();
185
186 void inc_free_chunks_total(size_t v, size_t count = 1) {
187 Atomic::add_ptr(count, &_free_chunks_count);
188 Atomic::add_ptr(v, &_free_chunks_total);
189 }
190 ChunkTreeDictionary* humongous_dictionary() {
191 return &_humongous_dictionary;
192 }
193
194 ChunkList* free_chunks(ChunkIndex index);
195
196 // Returns the list for the given chunk word size.
197 ChunkList* find_free_chunks_list(size_t word_size);
198
199 // Add and remove from a list by size. Selects
200 // list based on size of chunk.
201 void free_chunks_put(Metachunk* chuck);
202 Metachunk* free_chunks_get(size_t chunk_word_size);
203
204 // Debug support
205 void verify();
206 void slow_verify() {
207 if (metaspace_slow_verify) {
208 verify();
209 }
210 }
211 void locked_verify();
212 void slow_locked_verify() {
213 if (metaspace_slow_verify) {
214 locked_verify();
215 }
216 }
217 void verify_free_chunks_total();
218
219 void locked_print_free_chunks(outputStream* st);
220 void locked_print_sum_free_chunks(outputStream* st);
221
222 void print_on(outputStream* st);
223 };
224
225 // Used to manage the free list of Metablocks (a block corresponds
226 // to the allocation of a quantum of metadata).
227 class BlockFreelist VALUE_OBJ_CLASS_SPEC {
228 BlockTreeDictionary* _dictionary;
229 static Metablock* initialize_free_chunk(MetaWord* p, size_t word_size);
230
231 // Only allocate and split from freelist if the size of the allocation
232 // is at least 1/4th the size of the available block.
233 const static int WasteMultiplier = 4;
234
235 // Accessors
236 BlockTreeDictionary* dictionary() const { return _dictionary; }
237
238 public:
239 BlockFreelist();
240 ~BlockFreelist();
241
242 // Get and return a block to the free list
243 MetaWord* get_block(size_t word_size);
244 void return_block(MetaWord* p, size_t word_size);
245
246 size_t total_size() {
247 if (dictionary() == NULL) {
248 return 0;
249 } else {
250 return dictionary()->total_size();
251 }
252 }
253
254 void print_on(outputStream* st) const;
255 };
256
257 class VirtualSpaceNode : public CHeapObj<mtClass> {
258 friend class VirtualSpaceList;
259
260 // Link to next VirtualSpaceNode
261 VirtualSpaceNode* _next;
262
263 // total in the VirtualSpace
264 MemRegion _reserved;
265 ReservedSpace _rs;
266 VirtualSpace _virtual_space;
267 MetaWord* _top;
268 // count of chunks contained in this VirtualSpace
269 uintx _container_count;
270
271 // Convenience functions to access the _virtual_space
272 char* low() const { return virtual_space()->low(); }
273 char* high() const { return virtual_space()->high(); }
274
275 // The first Metachunk will be allocated at the bottom of the
276 // VirtualSpace
277 Metachunk* first_chunk() { return (Metachunk*) bottom(); }
278
279 void inc_container_count();
280 #ifdef ASSERT
281 uint container_count_slow();
282 #endif
283
284 public:
285
286 VirtualSpaceNode(size_t byte_size);
287 VirtualSpaceNode(ReservedSpace rs) : _top(NULL), _next(NULL), _rs(rs), _container_count(0) {}
288 ~VirtualSpaceNode();
289
290 // Convenience functions for logical bottom and end
291 MetaWord* bottom() const { return (MetaWord*) _virtual_space.low(); }
292 MetaWord* end() const { return (MetaWord*) _virtual_space.high(); }
293
294 size_t reserved_words() const { return _virtual_space.reserved_size() / BytesPerWord; }
295 size_t expanded_words() const { return _virtual_space.committed_size() / BytesPerWord; }
296 size_t committed_words() const { return _virtual_space.actual_committed_size() / BytesPerWord; }
297
298 // address of next available space in _virtual_space;
299 // Accessors
300 VirtualSpaceNode* next() { return _next; }
301 void set_next(VirtualSpaceNode* v) { _next = v; }
302
303 void set_reserved(MemRegion const v) { _reserved = v; }
304 void set_top(MetaWord* v) { _top = v; }
305
306 // Accessors
307 MemRegion* reserved() { return &_reserved; }
308 VirtualSpace* virtual_space() const { return (VirtualSpace*) &_virtual_space; }
309
310 // Returns true if "word_size" is available in the VirtualSpace
311 bool is_available(size_t word_size) { return _top + word_size <= end(); }
312
313 MetaWord* top() const { return _top; }
314 void inc_top(size_t word_size) { _top += word_size; }
315
316 uintx container_count() { return _container_count; }
317 void dec_container_count();
318 #ifdef ASSERT
319 void verify_container_count();
320 #endif
321
322 // used and capacity in this single entry in the list
323 size_t used_words_in_vs() const;
324 size_t capacity_words_in_vs() const;
325 size_t free_words_in_vs() const;
326
327 bool initialize();
328
329 // get space from the virtual space
330 Metachunk* take_from_committed(size_t chunk_word_size);
331
332 // Allocate a chunk from the virtual space and return it.
333 Metachunk* get_chunk_vs(size_t chunk_word_size);
334
335 // Expands/shrinks the committed space in a virtual space. Delegates
336 // to Virtualspace
337 bool expand_by(size_t words, bool pre_touch = false);
338
339 // In preparation for deleting this node, remove all the chunks
340 // in the node from any freelist.
341 void purge(ChunkManager* chunk_manager);
342
343 #ifdef ASSERT
344 // Debug support
345 void mangle();
346 #endif
347
348 void print_on(outputStream* st) const;
349 };
350
351 // byte_size is the size of the associated virtualspace.
352 VirtualSpaceNode::VirtualSpaceNode(size_t byte_size) : _top(NULL), _next(NULL), _rs(), _container_count(0) {
353 // align up to vm allocation granularity
354 byte_size = align_size_up(byte_size, os::vm_allocation_granularity());
355
356 // This allocates memory with mmap. For DumpSharedspaces, try to reserve
357 // configurable address, generally at the top of the Java heap so other
358 // memory addresses don't conflict.
359 if (DumpSharedSpaces) {
360 char* shared_base = (char*)SharedBaseAddress;
361 _rs = ReservedSpace(byte_size, 0, false, shared_base, 0);
362 if (_rs.is_reserved()) {
363 assert(shared_base == 0 || _rs.base() == shared_base, "should match");
364 } else {
365 // Get a mmap region anywhere if the SharedBaseAddress fails.
366 _rs = ReservedSpace(byte_size);
367 }
368 MetaspaceShared::set_shared_rs(&_rs);
369 } else {
370 _rs = ReservedSpace(byte_size);
371 }
372
373 MemTracker::record_virtual_memory_type((address)_rs.base(), mtClass);
374 }
375
376 void VirtualSpaceNode::purge(ChunkManager* chunk_manager) {
377 Metachunk* chunk = first_chunk();
378 Metachunk* invalid_chunk = (Metachunk*) top();
379 while (chunk < invalid_chunk ) {
380 assert(chunk->is_free(), "Should be marked free");
381 MetaWord* next = ((MetaWord*)chunk) + chunk->word_size();
382 chunk_manager->remove_chunk(chunk);
383 assert(chunk->next() == NULL &&
384 chunk->prev() == NULL,
385 "Was not removed from its list");
386 chunk = (Metachunk*) next;
387 }
388 }
389
390 #ifdef ASSERT
391 uint VirtualSpaceNode::container_count_slow() {
392 uint count = 0;
393 Metachunk* chunk = first_chunk();
394 Metachunk* invalid_chunk = (Metachunk*) top();
395 while (chunk < invalid_chunk ) {
396 MetaWord* next = ((MetaWord*)chunk) + chunk->word_size();
397 // Don't count the chunks on the free lists. Those are
398 // still part of the VirtualSpaceNode but not currently
399 // counted.
400 if (!chunk->is_free()) {
401 count++;
402 }
403 chunk = (Metachunk*) next;
404 }
405 return count;
406 }
407 #endif
408
409 // List of VirtualSpaces for metadata allocation.
410 // It has a _next link for singly linked list and a MemRegion
411 // for total space in the VirtualSpace.
412 class VirtualSpaceList : public CHeapObj<mtClass> {
413 friend class VirtualSpaceNode;
414
415 enum VirtualSpaceSizes {
416 VirtualSpaceSize = 256 * K
417 };
418
419 // Global list of virtual spaces
420 // Head of the list
421 VirtualSpaceNode* _virtual_space_list;
422 // virtual space currently being used for allocations
423 VirtualSpaceNode* _current_virtual_space;
424 // Free chunk list for all other metadata
425 ChunkManager _chunk_manager;
426
427 // Can this virtual list allocate >1 spaces? Also, used to determine
428 // whether to allocate unlimited small chunks in this virtual space
429 bool _is_class;
430 bool can_grow() const { return !is_class() || !UseCompressedClassPointers; }
431
432 // Sum of reserved and committed memory in the virtual spaces
433 size_t _reserved_words;
434 size_t _committed_words;
435
436 // Number of virtual spaces
437 size_t _virtual_space_count;
438
439 ~VirtualSpaceList();
440
441 VirtualSpaceNode* virtual_space_list() const { return _virtual_space_list; }
442
443 void set_virtual_space_list(VirtualSpaceNode* v) {
444 _virtual_space_list = v;
445 }
446 void set_current_virtual_space(VirtualSpaceNode* v) {
447 _current_virtual_space = v;
448 }
449
450 void link_vs(VirtualSpaceNode* new_entry);
451
452 // Get another virtual space and add it to the list. This
453 // is typically prompted by a failed attempt to allocate a chunk
454 // and is typically followed by the allocation of a chunk.
455 bool grow_vs(size_t vs_word_size);
456
457 public:
458 VirtualSpaceList(size_t word_size);
459 VirtualSpaceList(ReservedSpace rs);
460
461 size_t free_bytes();
462
463 Metachunk* get_new_chunk(size_t word_size,
464 size_t grow_chunks_by_words,
465 size_t medium_chunk_bunch);
466
467 bool expand_by(VirtualSpaceNode* node, size_t word_size, bool pre_touch = false);
468
469 // Get the first chunk for a Metaspace. Used for
470 // special cases such as the boot class loader, reflection
471 // class loader and anonymous class loader.
472 Metachunk* get_initialization_chunk(size_t word_size, size_t chunk_bunch);
473
474 VirtualSpaceNode* current_virtual_space() {
475 return _current_virtual_space;
476 }
477
478 ChunkManager* chunk_manager() { return &_chunk_manager; }
479 bool is_class() const { return _is_class; }
480
481 // Allocate the first virtualspace.
482 void initialize(size_t word_size);
483
484 size_t reserved_words() { return _reserved_words; }
485 size_t reserved_bytes() { return reserved_words() * BytesPerWord; }
486 size_t committed_words() { return _committed_words; }
487 size_t committed_bytes() { return committed_words() * BytesPerWord; }
488
489 void inc_reserved_words(size_t v);
490 void dec_reserved_words(size_t v);
491 void inc_committed_words(size_t v);
492 void dec_committed_words(size_t v);
493 void inc_virtual_space_count();
494 void dec_virtual_space_count();
495
496 // Unlink empty VirtualSpaceNodes and free it.
497 void purge();
498
499 // Used and capacity in the entire list of virtual spaces.
500 // These are global values shared by all Metaspaces
501 size_t capacity_words_sum();
502 size_t capacity_bytes_sum() { return capacity_words_sum() * BytesPerWord; }
503 size_t used_words_sum();
504 size_t used_bytes_sum() { return used_words_sum() * BytesPerWord; }
505
506 bool contains(const void *ptr);
507
508 void print_on(outputStream* st) const;
509
510 class VirtualSpaceListIterator : public StackObj {
511 VirtualSpaceNode* _virtual_spaces;
512 public:
513 VirtualSpaceListIterator(VirtualSpaceNode* virtual_spaces) :
514 _virtual_spaces(virtual_spaces) {}
515
516 bool repeat() {
517 return _virtual_spaces != NULL;
518 }
519
520 VirtualSpaceNode* get_next() {
521 VirtualSpaceNode* result = _virtual_spaces;
522 if (_virtual_spaces != NULL) {
523 _virtual_spaces = _virtual_spaces->next();
524 }
525 return result;
526 }
527 };
528 };
529
530 class Metadebug : AllStatic {
531 // Debugging support for Metaspaces
532 static int _deallocate_block_a_lot_count;
533 static int _deallocate_chunk_a_lot_count;
534 static int _allocation_fail_alot_count;
535
536 public:
537 static int deallocate_block_a_lot_count() {
538 return _deallocate_block_a_lot_count;
539 }
540 static void set_deallocate_block_a_lot_count(int v) {
541 _deallocate_block_a_lot_count = v;
542 }
543 static void inc_deallocate_block_a_lot_count() {
544 _deallocate_block_a_lot_count++;
545 }
546 static int deallocate_chunk_a_lot_count() {
547 return _deallocate_chunk_a_lot_count;
548 }
549 static void reset_deallocate_chunk_a_lot_count() {
550 _deallocate_chunk_a_lot_count = 1;
551 }
552 static void inc_deallocate_chunk_a_lot_count() {
553 _deallocate_chunk_a_lot_count++;
554 }
555
556 static void init_allocation_fail_alot_count();
557 #ifdef ASSERT
558 static bool test_metadata_failure();
559 #endif
560
561 static void deallocate_chunk_a_lot(SpaceManager* sm,
562 size_t chunk_word_size);
563 static void deallocate_block_a_lot(SpaceManager* sm,
564 size_t chunk_word_size);
565
566 };
567
568 int Metadebug::_deallocate_block_a_lot_count = 0;
569 int Metadebug::_deallocate_chunk_a_lot_count = 0;
570 int Metadebug::_allocation_fail_alot_count = 0;
571
572 // SpaceManager - used by Metaspace to handle allocations
573 class SpaceManager : public CHeapObj<mtClass> {
574 friend class Metaspace;
575 friend class Metadebug;
576
577 private:
578
579 // protects allocations and contains.
580 Mutex* const _lock;
581
582 // Type of metadata allocated.
583 Metaspace::MetadataType _mdtype;
584
585 // Chunk related size
586 size_t _medium_chunk_bunch;
587
588 // List of chunks in use by this SpaceManager. Allocations
589 // are done from the current chunk. The list is used for deallocating
590 // chunks when the SpaceManager is freed.
591 Metachunk* _chunks_in_use[NumberOfInUseLists];
592 Metachunk* _current_chunk;
593
594 // Virtual space where allocation comes from.
595 VirtualSpaceList* _vs_list;
596
597 // Number of small chunks to allocate to a manager
598 // If class space manager, small chunks are unlimited
599 static uint const _small_chunk_limit;
600
601 // Sum of all space in allocated chunks
602 size_t _allocated_blocks_words;
603
604 // Sum of all allocated chunks
605 size_t _allocated_chunks_words;
606 size_t _allocated_chunks_count;
607
608 // Free lists of blocks are per SpaceManager since they
609 // are assumed to be in chunks in use by the SpaceManager
610 // and all chunks in use by a SpaceManager are freed when
611 // the class loader using the SpaceManager is collected.
612 BlockFreelist _block_freelists;
613
614 // protects virtualspace and chunk expansions
615 static const char* _expand_lock_name;
616 static const int _expand_lock_rank;
617 static Mutex* const _expand_lock;
618
619 private:
620 // Accessors
621 Metachunk* chunks_in_use(ChunkIndex index) const { return _chunks_in_use[index]; }
622 void set_chunks_in_use(ChunkIndex index, Metachunk* v) { _chunks_in_use[index] = v; }
623
624 BlockFreelist* block_freelists() const {
625 return (BlockFreelist*) &_block_freelists;
626 }
627
628 Metaspace::MetadataType mdtype() { return _mdtype; }
629 VirtualSpaceList* vs_list() const { return _vs_list; }
630
631 Metachunk* current_chunk() const { return _current_chunk; }
632 void set_current_chunk(Metachunk* v) {
633 _current_chunk = v;
634 }
635
636 Metachunk* find_current_chunk(size_t word_size);
637
638 // Add chunk to the list of chunks in use
639 void add_chunk(Metachunk* v, bool make_current);
640 void retire_current_chunk();
641
642 Mutex* lock() const { return _lock; }
643
644 const char* chunk_size_name(ChunkIndex index) const;
645
646 protected:
647 void initialize();
648
649 public:
650 SpaceManager(Metaspace::MetadataType mdtype,
651 Mutex* lock,
652 VirtualSpaceList* vs_list);
653 ~SpaceManager();
654
655 enum ChunkMultiples {
656 MediumChunkMultiple = 4
657 };
658
659 // Accessors
660 size_t specialized_chunk_size() { return SpecializedChunk; }
661 size_t small_chunk_size() { return (size_t) vs_list()->is_class() ? ClassSmallChunk : SmallChunk; }
662 size_t medium_chunk_size() { return (size_t) vs_list()->is_class() ? ClassMediumChunk : MediumChunk; }
663 size_t medium_chunk_bunch() { return medium_chunk_size() * MediumChunkMultiple; }
664
665 size_t allocated_blocks_words() const { return _allocated_blocks_words; }
666 size_t allocated_blocks_bytes() const { return _allocated_blocks_words * BytesPerWord; }
667 size_t allocated_chunks_words() const { return _allocated_chunks_words; }
668 size_t allocated_chunks_count() const { return _allocated_chunks_count; }
669
670 bool is_humongous(size_t word_size) { return word_size > medium_chunk_size(); }
671
672 static Mutex* expand_lock() { return _expand_lock; }
673
674 // Increment the per Metaspace and global running sums for Metachunks
675 // by the given size. This is used when a Metachunk to added to
676 // the in-use list.
677 void inc_size_metrics(size_t words);
678 // Increment the per Metaspace and global running sums Metablocks by the given
679 // size. This is used when a Metablock is allocated.
680 void inc_used_metrics(size_t words);
681 // Delete the portion of the running sums for this SpaceManager. That is,
682 // the globals running sums for the Metachunks and Metablocks are
683 // decremented for all the Metachunks in-use by this SpaceManager.
684 void dec_total_from_size_metrics();
685
686 // Set the sizes for the initial chunks.
687 void get_initial_chunk_sizes(Metaspace::MetaspaceType type,
688 size_t* chunk_word_size,
689 size_t* class_chunk_word_size);
690
691 size_t sum_capacity_in_chunks_in_use() const;
692 size_t sum_used_in_chunks_in_use() const;
693 size_t sum_free_in_chunks_in_use() const;
694 size_t sum_waste_in_chunks_in_use() const;
695 size_t sum_waste_in_chunks_in_use(ChunkIndex index ) const;
696
697 size_t sum_count_in_chunks_in_use();
698 size_t sum_count_in_chunks_in_use(ChunkIndex i);
699
700 Metachunk* get_new_chunk(size_t word_size, size_t grow_chunks_by_words);
701
702 // Block allocation and deallocation.
703 // Allocates a block from the current chunk
704 MetaWord* allocate(size_t word_size);
705
706 // Helper for allocations
707 MetaWord* allocate_work(size_t word_size);
708
709 // Returns a block to the per manager freelist
710 void deallocate(MetaWord* p, size_t word_size);
711
712 // Based on the allocation size and a minimum chunk size,
713 // returned chunk size (for expanding space for chunk allocation).
714 size_t calc_chunk_size(size_t allocation_word_size);
715
716 // Called when an allocation from the current chunk fails.
717 // Gets a new chunk (may require getting a new virtual space),
718 // and allocates from that chunk.
719 MetaWord* grow_and_allocate(size_t word_size);
720
721 // debugging support.
722
723 void dump(outputStream* const out) const;
724 void print_on(outputStream* st) const;
725 void locked_print_chunks_in_use_on(outputStream* st) const;
726
727 void verify();
728 void verify_chunk_size(Metachunk* chunk);
729 NOT_PRODUCT(void mangle_freed_chunks();)
730 #ifdef ASSERT
731 void verify_allocated_blocks_words();
732 #endif
733
734 size_t get_raw_word_size(size_t word_size) {
735 // If only the dictionary is going to be used (i.e., no
736 // indexed free list), then there is a minimum size requirement.
737 // MinChunkSize is a placeholder for the real minimum size JJJ
738 size_t byte_size = word_size * BytesPerWord;
739
740 size_t raw_bytes_size = MAX2(byte_size,
741 Metablock::min_block_byte_size());
742 raw_bytes_size = ARENA_ALIGN(raw_bytes_size);
743 size_t raw_word_size = raw_bytes_size / BytesPerWord;
744 assert(raw_word_size * BytesPerWord == raw_bytes_size, "Size problem");
745
746 return raw_word_size;
747 }
748 };
749
750 uint const SpaceManager::_small_chunk_limit = 4;
751
752 const char* SpaceManager::_expand_lock_name =
753 "SpaceManager chunk allocation lock";
754 const int SpaceManager::_expand_lock_rank = Monitor::leaf - 1;
755 Mutex* const SpaceManager::_expand_lock =
756 new Mutex(SpaceManager::_expand_lock_rank,
757 SpaceManager::_expand_lock_name,
758 Mutex::_allow_vm_block_flag);
759
760 void VirtualSpaceNode::inc_container_count() {
761 assert_lock_strong(SpaceManager::expand_lock());
762 _container_count++;
763 assert(_container_count == container_count_slow(),
764 err_msg("Inconsistency in countainer_count _container_count " SIZE_FORMAT
765 "container_count_slow() " SIZE_FORMAT,
766 _container_count, container_count_slow()));
767 }
768
769 void VirtualSpaceNode::dec_container_count() {
770 assert_lock_strong(SpaceManager::expand_lock());
771 _container_count--;
772 }
773
774 #ifdef ASSERT
775 void VirtualSpaceNode::verify_container_count() {
776 assert(_container_count == container_count_slow(),
777 err_msg("Inconsistency in countainer_count _container_count " SIZE_FORMAT
778 "container_count_slow() " SIZE_FORMAT, _container_count, container_count_slow()));
779 }
780 #endif
781
782 // BlockFreelist methods
783
784 BlockFreelist::BlockFreelist() : _dictionary(NULL) {}
785
786 BlockFreelist::~BlockFreelist() {
787 if (_dictionary != NULL) {
788 if (Verbose && TraceMetadataChunkAllocation) {
789 _dictionary->print_free_lists(gclog_or_tty);
790 }
791 delete _dictionary;
792 }
793 }
794
795 Metablock* BlockFreelist::initialize_free_chunk(MetaWord* p, size_t word_size) {
796 Metablock* block = (Metablock*) p;
797 block->set_word_size(word_size);
798 block->set_prev(NULL);
799 block->set_next(NULL);
800
801 return block;
802 }
803
804 void BlockFreelist::return_block(MetaWord* p, size_t word_size) {
805 Metablock* free_chunk = initialize_free_chunk(p, word_size);
806 if (dictionary() == NULL) {
807 _dictionary = new BlockTreeDictionary();
808 }
809 dictionary()->return_chunk(free_chunk);
810 }
811
812 MetaWord* BlockFreelist::get_block(size_t word_size) {
813 if (dictionary() == NULL) {
814 return NULL;
815 }
816
817 if (word_size < TreeChunk<Metablock, FreeList>::min_size()) {
818 // Dark matter. Too small for dictionary.
819 return NULL;
820 }
821
822 Metablock* free_block =
823 dictionary()->get_chunk(word_size, FreeBlockDictionary<Metablock>::atLeast);
824 if (free_block == NULL) {
825 return NULL;
826 }
827
828 const size_t block_size = free_block->size();
829 if (block_size > WasteMultiplier * word_size) {
830 return_block((MetaWord*)free_block, block_size);
831 return NULL;
832 }
833
834 MetaWord* new_block = (MetaWord*)free_block;
835 assert(block_size >= word_size, "Incorrect size of block from freelist");
836 const size_t unused = block_size - word_size;
837 if (unused >= TreeChunk<Metablock, FreeList>::min_size()) {
838 return_block(new_block + word_size, unused);
839 }
840
841 return new_block;
842 }
843
844 void BlockFreelist::print_on(outputStream* st) const {
845 if (dictionary() == NULL) {
846 return;
847 }
848 dictionary()->print_free_lists(st);
849 }
850
851 // VirtualSpaceNode methods
852
853 VirtualSpaceNode::~VirtualSpaceNode() {
854 _rs.release();
855 #ifdef ASSERT
856 size_t word_size = sizeof(*this) / BytesPerWord;
857 Copy::fill_to_words((HeapWord*) this, word_size, 0xf1f1f1f1);
858 #endif
859 }
860
861 size_t VirtualSpaceNode::used_words_in_vs() const {
862 return pointer_delta(top(), bottom(), sizeof(MetaWord));
863 }
864
865 // Space committed in the VirtualSpace
866 size_t VirtualSpaceNode::capacity_words_in_vs() const {
867 return pointer_delta(end(), bottom(), sizeof(MetaWord));
868 }
869
870 size_t VirtualSpaceNode::free_words_in_vs() const {
871 return pointer_delta(end(), top(), sizeof(MetaWord));
872 }
873
874 // Allocates the chunk from the virtual space only.
875 // This interface is also used internally for debugging. Not all
876 // chunks removed here are necessarily used for allocation.
877 Metachunk* VirtualSpaceNode::take_from_committed(size_t chunk_word_size) {
878 // Bottom of the new chunk
879 MetaWord* chunk_limit = top();
880 assert(chunk_limit != NULL, "Not safe to call this method");
881
882 if (!is_available(chunk_word_size)) {
883 if (TraceMetadataChunkAllocation) {
884 gclog_or_tty->print("VirtualSpaceNode::take_from_committed() not available %d words ", chunk_word_size);
885 // Dump some information about the virtual space that is nearly full
886 print_on(gclog_or_tty);
887 }
888 return NULL;
889 }
890
891 // Take the space (bump top on the current virtual space).
892 inc_top(chunk_word_size);
893
894 // Initialize the chunk
895 Metachunk* result = ::new (chunk_limit) Metachunk(chunk_word_size, this);
896 return result;
897 }
898
899
900 // Expand the virtual space (commit more of the reserved space)
901 bool VirtualSpaceNode::expand_by(size_t words, bool pre_touch) {
902 size_t bytes = words * BytesPerWord;
903 bool result = virtual_space()->expand_by(bytes, pre_touch);
904 if (TraceMetavirtualspaceAllocation && !result) {
905 gclog_or_tty->print_cr("VirtualSpaceNode::expand_by() failed "
906 "for byte size " SIZE_FORMAT, bytes);
907 virtual_space()->print_on(gclog_or_tty);
908 }
909 return result;
910 }
911
912 Metachunk* VirtualSpaceNode::get_chunk_vs(size_t chunk_word_size) {
913 assert_lock_strong(SpaceManager::expand_lock());
914 Metachunk* result = take_from_committed(chunk_word_size);
915 if (result != NULL) {
916 inc_container_count();
917 }
918 return result;
919 }
920
921 bool VirtualSpaceNode::initialize() {
922
923 if (!_rs.is_reserved()) {
924 return false;
925 }
926
927 // An allocation out of this Virtualspace that is larger
928 // than an initial commit size can waste that initial committed
929 // space.
930 size_t committed_byte_size = 0;
931 bool result = virtual_space()->initialize(_rs, committed_byte_size);
932 if (result) {
933 set_top((MetaWord*)virtual_space()->low());
934 set_reserved(MemRegion((HeapWord*)_rs.base(),
935 (HeapWord*)(_rs.base() + _rs.size())));
936
937 assert(reserved()->start() == (HeapWord*) _rs.base(),
938 err_msg("Reserved start was not set properly " PTR_FORMAT
939 " != " PTR_FORMAT, reserved()->start(), _rs.base()));
940 assert(reserved()->word_size() == _rs.size() / BytesPerWord,
941 err_msg("Reserved size was not set properly " SIZE_FORMAT
942 " != " SIZE_FORMAT, reserved()->word_size(),
943 _rs.size() / BytesPerWord));
944 }
945
946 return result;
947 }
948
949 void VirtualSpaceNode::print_on(outputStream* st) const {
950 size_t used = used_words_in_vs();
951 size_t capacity = capacity_words_in_vs();
952 VirtualSpace* vs = virtual_space();
953 st->print_cr(" space @ " PTR_FORMAT " " SIZE_FORMAT "K, %3d%% used "
954 "[" PTR_FORMAT ", " PTR_FORMAT ", "
955 PTR_FORMAT ", " PTR_FORMAT ")",
956 vs, capacity / K,
957 capacity == 0 ? 0 : used * 100 / capacity,
958 bottom(), top(), end(),
959 vs->high_boundary());
960 }
961
962 #ifdef ASSERT
963 void VirtualSpaceNode::mangle() {
964 size_t word_size = capacity_words_in_vs();
965 Copy::fill_to_words((HeapWord*) low(), word_size, 0xf1f1f1f1);
966 }
967 #endif // ASSERT
968
969 // VirtualSpaceList methods
970 // Space allocated from the VirtualSpace
971
972 VirtualSpaceList::~VirtualSpaceList() {
973 VirtualSpaceListIterator iter(virtual_space_list());
974 while (iter.repeat()) {
975 VirtualSpaceNode* vsl = iter.get_next();
976 delete vsl;
977 }
978 }
979
980 void VirtualSpaceList::inc_reserved_words(size_t v) {
981 assert_lock_strong(SpaceManager::expand_lock());
982 _reserved_words = _reserved_words + v;
983 }
984 void VirtualSpaceList::dec_reserved_words(size_t v) {
985 assert_lock_strong(SpaceManager::expand_lock());
986 _reserved_words = _reserved_words - v;
987 }
988
989 void VirtualSpaceList::inc_committed_words(size_t v) {
990 assert_lock_strong(SpaceManager::expand_lock());
991 _committed_words = _committed_words + v;
992 }
993 void VirtualSpaceList::dec_committed_words(size_t v) {
994 assert_lock_strong(SpaceManager::expand_lock());
995 _committed_words = _committed_words - v;
996 }
997
998 void VirtualSpaceList::inc_virtual_space_count() {
999 assert_lock_strong(SpaceManager::expand_lock());
1000 _virtual_space_count++;
1001 }
1002 void VirtualSpaceList::dec_virtual_space_count() {
1003 assert_lock_strong(SpaceManager::expand_lock());
1004 _virtual_space_count--;
1005 }
1006
1007 void ChunkManager::remove_chunk(Metachunk* chunk) {
1008 size_t word_size = chunk->word_size();
1009 ChunkIndex index = list_index(word_size);
1010 if (index != HumongousIndex) {
1011 free_chunks(index)->remove_chunk(chunk);
1012 } else {
1013 humongous_dictionary()->remove_chunk(chunk);
1014 }
1015
1016 // Chunk is being removed from the chunks free list.
1017 dec_free_chunks_total(chunk->capacity_word_size());
1018 }
1019
1020 // Walk the list of VirtualSpaceNodes and delete
1021 // nodes with a 0 container_count. Remove Metachunks in
1022 // the node from their respective freelists.
1023 void VirtualSpaceList::purge() {
1024 assert_lock_strong(SpaceManager::expand_lock());
1025 // Don't use a VirtualSpaceListIterator because this
1026 // list is being changed and a straightforward use of an iterator is not safe.
1027 VirtualSpaceNode* purged_vsl = NULL;
1028 VirtualSpaceNode* prev_vsl = virtual_space_list();
1029 VirtualSpaceNode* next_vsl = prev_vsl;
1030 while (next_vsl != NULL) {
1031 VirtualSpaceNode* vsl = next_vsl;
1032 next_vsl = vsl->next();
1033 // Don't free the current virtual space since it will likely
1034 // be needed soon.
1035 if (vsl->container_count() == 0 && vsl != current_virtual_space()) {
1036 // Unlink it from the list
1037 if (prev_vsl == vsl) {
1038 // This is the case of the current note being the first note.
1039 assert(vsl == virtual_space_list(), "Expected to be the first note");
1040 set_virtual_space_list(vsl->next());
1041 } else {
1042 prev_vsl->set_next(vsl->next());
1043 }
1044
1045 vsl->purge(chunk_manager());
1046 dec_reserved_words(vsl->reserved_words());
1047 dec_committed_words(vsl->committed_words());
1048 dec_virtual_space_count();
1049 purged_vsl = vsl;
1050 delete vsl;
1051 } else {
1052 prev_vsl = vsl;
1053 }
1054 }
1055 #ifdef ASSERT
1056 if (purged_vsl != NULL) {
1057 // List should be stable enough to use an iterator here.
1058 VirtualSpaceListIterator iter(virtual_space_list());
1059 while (iter.repeat()) {
1060 VirtualSpaceNode* vsl = iter.get_next();
1061 assert(vsl != purged_vsl, "Purge of vsl failed");
1062 }
1063 }
1064 #endif
1065 }
1066
1067 size_t VirtualSpaceList::used_words_sum() {
1068 size_t allocated_by_vs = 0;
1069 VirtualSpaceListIterator iter(virtual_space_list());
1070 while (iter.repeat()) {
1071 VirtualSpaceNode* vsl = iter.get_next();
1072 // Sum used region [bottom, top) in each virtualspace
1073 allocated_by_vs += vsl->used_words_in_vs();
1074 }
1075 assert(allocated_by_vs >= chunk_manager()->free_chunks_total_words(),
1076 err_msg("Total in free chunks " SIZE_FORMAT
1077 " greater than total from virtual_spaces " SIZE_FORMAT,
1078 allocated_by_vs, chunk_manager()->free_chunks_total_words()));
1079 size_t used =
1080 allocated_by_vs - chunk_manager()->free_chunks_total_words();
1081 return used;
1082 }
1083
1084 // Space available in all MetadataVirtualspaces allocated
1085 // for metadata. This is the upper limit on the capacity
1086 // of chunks allocated out of all the MetadataVirtualspaces.
1087 size_t VirtualSpaceList::capacity_words_sum() {
1088 size_t capacity = 0;
1089 VirtualSpaceListIterator iter(virtual_space_list());
1090 while (iter.repeat()) {
1091 VirtualSpaceNode* vsl = iter.get_next();
1092 capacity += vsl->capacity_words_in_vs();
1093 }
1094 return capacity;
1095 }
1096
1097 VirtualSpaceList::VirtualSpaceList(size_t word_size ) :
1098 _is_class(false),
1099 _virtual_space_list(NULL),
1100 _current_virtual_space(NULL),
1101 _reserved_words(0),
1102 _committed_words(0),
1103 _virtual_space_count(0) {
1104 MutexLockerEx cl(SpaceManager::expand_lock(),
1105 Mutex::_no_safepoint_check_flag);
1106 bool initialization_succeeded = grow_vs(word_size);
1107
1108 _chunk_manager.free_chunks(SpecializedIndex)->set_size(SpecializedChunk);
1109 _chunk_manager.free_chunks(SmallIndex)->set_size(SmallChunk);
1110 _chunk_manager.free_chunks(MediumIndex)->set_size(MediumChunk);
1111 assert(initialization_succeeded,
1112 " VirtualSpaceList initialization should not fail");
1113 }
1114
1115 VirtualSpaceList::VirtualSpaceList(ReservedSpace rs) :
1116 _is_class(true),
1117 _virtual_space_list(NULL),
1118 _current_virtual_space(NULL),
1119 _reserved_words(0),
1120 _committed_words(0),
1121 _virtual_space_count(0) {
1122 MutexLockerEx cl(SpaceManager::expand_lock(),
1123 Mutex::_no_safepoint_check_flag);
1124 VirtualSpaceNode* class_entry = new VirtualSpaceNode(rs);
1125 bool succeeded = class_entry->initialize();
1126 _chunk_manager.free_chunks(SpecializedIndex)->set_size(SpecializedChunk);
1127 _chunk_manager.free_chunks(SmallIndex)->set_size(ClassSmallChunk);
1128 _chunk_manager.free_chunks(MediumIndex)->set_size(ClassMediumChunk);
1129 assert(succeeded, " VirtualSpaceList initialization should not fail");
1130 link_vs(class_entry);
1131 }
1132
1133 size_t VirtualSpaceList::free_bytes() {
1134 return virtual_space_list()->free_words_in_vs() * BytesPerWord;
1135 }
1136
1137 // Allocate another meta virtual space and add it to the list.
1138 bool VirtualSpaceList::grow_vs(size_t vs_word_size) {
1139 assert_lock_strong(SpaceManager::expand_lock());
1140 if (vs_word_size == 0) {
1141 return false;
1142 }
1143 // Reserve the space
1144 size_t vs_byte_size = vs_word_size * BytesPerWord;
1145 assert(vs_byte_size % os::vm_page_size() == 0, "Not aligned");
1146
1147 // Allocate the meta virtual space and initialize it.
1148 VirtualSpaceNode* new_entry = new VirtualSpaceNode(vs_byte_size);
1149 if (!new_entry->initialize()) {
1150 delete new_entry;
1151 return false;
1152 } else {
1153 assert(new_entry->reserved_words() == vs_word_size, "Must be");
1154 // ensure lock-free iteration sees fully initialized node
1155 OrderAccess::storestore();
1156 link_vs(new_entry);
1157 return true;
1158 }
1159 }
1160
1161 void VirtualSpaceList::link_vs(VirtualSpaceNode* new_entry) {
1162 if (virtual_space_list() == NULL) {
1163 set_virtual_space_list(new_entry);
1164 } else {
1165 current_virtual_space()->set_next(new_entry);
1166 }
1167 set_current_virtual_space(new_entry);
1168 inc_reserved_words(new_entry->reserved_words());
1169 inc_committed_words(new_entry->committed_words());
1170 inc_virtual_space_count();
1171 #ifdef ASSERT
1172 new_entry->mangle();
1173 #endif
1174 if (TraceMetavirtualspaceAllocation && Verbose) {
1175 VirtualSpaceNode* vsl = current_virtual_space();
1176 vsl->print_on(gclog_or_tty);
1177 }
1178 }
1179
1180 bool VirtualSpaceList::expand_by(VirtualSpaceNode* node, size_t word_size, bool pre_touch) {
1181 size_t before = node->committed_words();
1182
1183 bool result = node->expand_by(word_size, pre_touch);
1184
1185 size_t after = node->committed_words();
1186
1187 // after and before can be the same if the memory was pre-committed.
1188 assert(after >= before, "Must be");
1189 inc_committed_words(after - before);
1190
1191 return result;
1192 }
1193
1194 Metachunk* VirtualSpaceList::get_new_chunk(size_t word_size,
1195 size_t grow_chunks_by_words,
1196 size_t medium_chunk_bunch) {
1197
1198 // Get a chunk from the chunk freelist
1199 Metachunk* next = chunk_manager()->chunk_freelist_allocate(grow_chunks_by_words);
1200
1201 if (next != NULL) {
1202 next->container()->inc_container_count();
1203 } else {
1204 // Allocate a chunk out of the current virtual space.
1205 next = current_virtual_space()->get_chunk_vs(grow_chunks_by_words);
1206 }
1207
1208 if (next == NULL) {
1209 // Not enough room in current virtual space. Try to commit
1210 // more space.
1211 size_t expand_vs_by_words = MAX2(medium_chunk_bunch,
1212 grow_chunks_by_words);
1213 size_t page_size_words = os::vm_page_size() / BytesPerWord;
1214 size_t aligned_expand_vs_by_words = align_size_up(expand_vs_by_words,
1215 page_size_words);
1216 bool vs_expanded =
1217 expand_by(current_virtual_space(), aligned_expand_vs_by_words);
1218 if (!vs_expanded) {
1219 // Should the capacity of the metaspaces be expanded for
1220 // this allocation? If it's the virtual space for classes and is
1221 // being used for CompressedHeaders, don't allocate a new virtualspace.
1222 if (can_grow() && MetaspaceGC::should_expand(this, word_size)) {
1223 // Get another virtual space.
1224 size_t grow_vs_words =
1225 MAX2((size_t)VirtualSpaceSize, aligned_expand_vs_by_words);
1226 if (grow_vs(grow_vs_words)) {
1227 // Got it. It's on the list now. Get a chunk from it.
1228 assert(current_virtual_space()->expanded_words() == 0,
1229 "New virtuals space nodes should not have expanded");
1230
1231 size_t grow_chunks_by_words_aligned = align_size_up(grow_chunks_by_words,
1232 page_size_words);
1233 // We probably want to expand by aligned_expand_vs_by_words here.
1234 expand_by(current_virtual_space(), grow_chunks_by_words_aligned);
1235 next = current_virtual_space()->get_chunk_vs(grow_chunks_by_words);
1236 }
1237 } else {
1238 // Allocation will fail and induce a GC
1239 if (TraceMetadataChunkAllocation && Verbose) {
1240 gclog_or_tty->print_cr("VirtualSpaceList::get_new_chunk():"
1241 " Fail instead of expand the metaspace");
1242 }
1243 }
1244 } else {
1245 // The virtual space expanded, get a new chunk
1246 next = current_virtual_space()->get_chunk_vs(grow_chunks_by_words);
1247 assert(next != NULL, "Just expanded, should succeed");
1248 }
1249 }
1250
1251 assert(next == NULL || (next->next() == NULL && next->prev() == NULL),
1252 "New chunk is still on some list");
1253 return next;
1254 }
1255
1256 Metachunk* VirtualSpaceList::get_initialization_chunk(size_t chunk_word_size,
1257 size_t chunk_bunch) {
1258 // Get a chunk from the chunk freelist
1259 Metachunk* new_chunk = get_new_chunk(chunk_word_size,
1260 chunk_word_size,
1261 chunk_bunch);
1262 return new_chunk;
1263 }
1264
1265 void VirtualSpaceList::print_on(outputStream* st) const {
1266 if (TraceMetadataChunkAllocation && Verbose) {
1267 VirtualSpaceListIterator iter(virtual_space_list());
1268 while (iter.repeat()) {
1269 VirtualSpaceNode* node = iter.get_next();
1270 node->print_on(st);
1271 }
1272 }
1273 }
1274
1275 bool VirtualSpaceList::contains(const void *ptr) {
1276 VirtualSpaceNode* list = virtual_space_list();
1277 VirtualSpaceListIterator iter(list);
1278 while (iter.repeat()) {
1279 VirtualSpaceNode* node = iter.get_next();
1280 if (node->reserved()->contains(ptr)) {
1281 return true;
1282 }
1283 }
1284 return false;
1285 }
1286
1287
1288 // MetaspaceGC methods
1289
1290 // VM_CollectForMetadataAllocation is the vm operation used to GC.
1291 // Within the VM operation after the GC the attempt to allocate the metadata
1292 // should succeed. If the GC did not free enough space for the metaspace
1293 // allocation, the HWM is increased so that another virtualspace will be
1294 // allocated for the metadata. With perm gen the increase in the perm
1295 // gen had bounds, MinMetaspaceExpansion and MaxMetaspaceExpansion. The
1296 // metaspace policy uses those as the small and large steps for the HWM.
1297 //
1298 // After the GC the compute_new_size() for MetaspaceGC is called to
1299 // resize the capacity of the metaspaces. The current implementation
1300 // is based on the flags MinMetaspaceFreeRatio and MaxMetaspaceFreeRatio used
1301 // to resize the Java heap by some GC's. New flags can be implemented
1302 // if really needed. MinMetaspaceFreeRatio is used to calculate how much
1303 // free space is desirable in the metaspace capacity to decide how much
1304 // to increase the HWM. MaxMetaspaceFreeRatio is used to decide how much
1305 // free space is desirable in the metaspace capacity before decreasing
1306 // the HWM.
1307
1308 // Calculate the amount to increase the high water mark (HWM).
1309 // Increase by a minimum amount (MinMetaspaceExpansion) so that
1310 // another expansion is not requested too soon. If that is not
1311 // enough to satisfy the allocation (i.e. big enough for a word_size
1312 // allocation), increase by MaxMetaspaceExpansion. If that is still
1313 // not enough, expand by the size of the allocation (word_size) plus
1314 // some.
1315 size_t MetaspaceGC::delta_capacity_until_GC(size_t word_size) {
1316 size_t before_inc = MetaspaceGC::capacity_until_GC();
1317 size_t min_delta_words = MinMetaspaceExpansion / BytesPerWord;
1318 size_t max_delta_words = MaxMetaspaceExpansion / BytesPerWord;
1319 size_t page_size_words = os::vm_page_size() / BytesPerWord;
1320 size_t size_delta_words = align_size_up(word_size, page_size_words);
1321 size_t delta_words = MAX2(size_delta_words, min_delta_words);
1322 if (delta_words > min_delta_words) {
1323 // Don't want to hit the high water mark on the next
1324 // allocation so make the delta greater than just enough
1325 // for this allocation.
1326 delta_words = MAX2(delta_words, max_delta_words);
1327 if (delta_words > max_delta_words) {
1328 // This allocation is large but the next ones are probably not
1329 // so increase by the minimum.
1330 delta_words = delta_words + min_delta_words;
1331 }
1332 }
1333 return delta_words;
1334 }
1335
1336 bool MetaspaceGC::should_expand(VirtualSpaceList* vsl, size_t word_size) {
1337
1338 // If the user wants a limit, impose one.
1339 // The reason for someone using this flag is to limit reserved space. So
1340 // for non-class virtual space, compare against virtual spaces that are reserved.
1341 // For class virtual space, we only compare against the committed space, not
1342 // reserved space, because this is a larger space prereserved for compressed
1343 // class pointers.
1344 if (!FLAG_IS_DEFAULT(MaxMetaspaceSize)) {
1345 size_t nonclass_allocated = MetaspaceAux::reserved_bytes(Metaspace::NonClassType);
1346 size_t class_allocated = MetaspaceAux::allocated_capacity_bytes(Metaspace::ClassType);
1347 size_t real_allocated = nonclass_allocated + real_allocated;
1348 if (real_allocated >= MaxMetaspaceSize) {
1349 return false;
1350 }
1351 }
1352
1353 // Class virtual space should always be expanded. Call GC for the other
1354 // metadata virtual space.
1355 if (Metaspace::using_class_space() &&
1356 (vsl == Metaspace::class_space_list())) return true;
1357
1358 // If this is part of an allocation after a GC, expand
1359 // unconditionally.
1360 if (MetaspaceGC::expand_after_GC()) {
1361 return true;
1362 }
1363
1364
1365 // If the capacity is below the minimum capacity, allow the
1366 // expansion. Also set the high-water-mark (capacity_until_GC)
1367 // to that minimum capacity so that a GC will not be induced
1368 // until that minimum capacity is exceeded.
1369 size_t committed_capacity_bytes = MetaspaceAux::allocated_capacity_bytes();
1370 size_t metaspace_size_bytes = MetaspaceSize;
1371 if (committed_capacity_bytes < metaspace_size_bytes ||
1372 capacity_until_GC() == 0) {
1373 set_capacity_until_GC(metaspace_size_bytes);
1374 return true;
1375 } else {
1376 if (committed_capacity_bytes < capacity_until_GC()) {
1377 return true;
1378 } else {
1379 if (TraceMetadataChunkAllocation && Verbose) {
1380 gclog_or_tty->print_cr(" allocation request size " SIZE_FORMAT
1381 " capacity_until_GC " SIZE_FORMAT
1382 " allocated_capacity_bytes " SIZE_FORMAT,
1383 word_size,
1384 capacity_until_GC(),
1385 MetaspaceAux::allocated_capacity_bytes());
1386 }
1387 return false;
1388 }
1389 }
1390 }
1391
1392
1393
1394 void MetaspaceGC::compute_new_size() {
1395 assert(_shrink_factor <= 100, "invalid shrink factor");
1396 uint current_shrink_factor = _shrink_factor;
1397 _shrink_factor = 0;
1398
1399 // Until a faster way of calculating the "used" quantity is implemented,
1400 // use "capacity".
1401 const size_t used_after_gc = MetaspaceAux::allocated_capacity_bytes();
1402 const size_t capacity_until_GC = MetaspaceGC::capacity_until_GC();
1403
1404 const double minimum_free_percentage = MinMetaspaceFreeRatio / 100.0;
1405 const double maximum_used_percentage = 1.0 - minimum_free_percentage;
1406
1407 const double min_tmp = used_after_gc / maximum_used_percentage;
1408 size_t minimum_desired_capacity =
1409 (size_t)MIN2(min_tmp, double(max_uintx));
1410 // Don't shrink less than the initial generation size
1411 minimum_desired_capacity = MAX2(minimum_desired_capacity,
1412 MetaspaceSize);
1413
1414 if (PrintGCDetails && Verbose) {
1415 gclog_or_tty->print_cr("\nMetaspaceGC::compute_new_size: ");
1416 gclog_or_tty->print_cr(" "
1417 " minimum_free_percentage: %6.2f"
1418 " maximum_used_percentage: %6.2f",
1419 minimum_free_percentage,
1420 maximum_used_percentage);
1421 gclog_or_tty->print_cr(" "
1422 " used_after_gc : %6.1fKB",
1423 used_after_gc / (double) K);
1424 }
1425
1426
1427 size_t shrink_bytes = 0;
1428 if (capacity_until_GC < minimum_desired_capacity) {
1429 // If we have less capacity below the metaspace HWM, then
1430 // increment the HWM.
1431 size_t expand_bytes = minimum_desired_capacity - capacity_until_GC;
1432 // Don't expand unless it's significant
1433 if (expand_bytes >= MinMetaspaceExpansion) {
1434 MetaspaceGC::set_capacity_until_GC(capacity_until_GC + expand_bytes);
1435 }
1436 if (PrintGCDetails && Verbose) {
1437 size_t new_capacity_until_GC = capacity_until_GC;
1438 gclog_or_tty->print_cr(" expanding:"
1439 " minimum_desired_capacity: %6.1fKB"
1440 " expand_bytes: %6.1fKB"
1441 " MinMetaspaceExpansion: %6.1fKB"
1442 " new metaspace HWM: %6.1fKB",
1443 minimum_desired_capacity / (double) K,
1444 expand_bytes / (double) K,
1445 MinMetaspaceExpansion / (double) K,
1446 new_capacity_until_GC / (double) K);
1447 }
1448 return;
1449 }
1450
1451 // No expansion, now see if we want to shrink
1452 // We would never want to shrink more than this
1453 size_t max_shrink_bytes = capacity_until_GC - minimum_desired_capacity;
1454 assert(max_shrink_bytes >= 0, err_msg("max_shrink_bytes " SIZE_FORMAT,
1455 max_shrink_bytes));
1456
1457 // Should shrinking be considered?
1458 if (MaxMetaspaceFreeRatio < 100) {
1459 const double maximum_free_percentage = MaxMetaspaceFreeRatio / 100.0;
1460 const double minimum_used_percentage = 1.0 - maximum_free_percentage;
1461 const double max_tmp = used_after_gc / minimum_used_percentage;
1462 size_t maximum_desired_capacity = (size_t)MIN2(max_tmp, double(max_uintx));
1463 maximum_desired_capacity = MAX2(maximum_desired_capacity,
1464 MetaspaceSize);
1465 if (PrintGCDetails && Verbose) {
1466 gclog_or_tty->print_cr(" "
1467 " maximum_free_percentage: %6.2f"
1468 " minimum_used_percentage: %6.2f",
1469 maximum_free_percentage,
1470 minimum_used_percentage);
1471 gclog_or_tty->print_cr(" "
1472 " minimum_desired_capacity: %6.1fKB"
1473 " maximum_desired_capacity: %6.1fKB",
1474 minimum_desired_capacity / (double) K,
1475 maximum_desired_capacity / (double) K);
1476 }
1477
1478 assert(minimum_desired_capacity <= maximum_desired_capacity,
1479 "sanity check");
1480
1481 if (capacity_until_GC > maximum_desired_capacity) {
1482 // Capacity too large, compute shrinking size
1483 shrink_bytes = capacity_until_GC - maximum_desired_capacity;
1484 // We don't want shrink all the way back to initSize if people call
1485 // System.gc(), because some programs do that between "phases" and then
1486 // we'd just have to grow the heap up again for the next phase. So we
1487 // damp the shrinking: 0% on the first call, 10% on the second call, 40%
1488 // on the third call, and 100% by the fourth call. But if we recompute
1489 // size without shrinking, it goes back to 0%.
1490 shrink_bytes = shrink_bytes / 100 * current_shrink_factor;
1491 assert(shrink_bytes <= max_shrink_bytes,
1492 err_msg("invalid shrink size " SIZE_FORMAT " not <= " SIZE_FORMAT,
1493 shrink_bytes, max_shrink_bytes));
1494 if (current_shrink_factor == 0) {
1495 _shrink_factor = 10;
1496 } else {
1497 _shrink_factor = MIN2(current_shrink_factor * 4, (uint) 100);
1498 }
1499 if (PrintGCDetails && Verbose) {
1500 gclog_or_tty->print_cr(" "
1501 " shrinking:"
1502 " initSize: %.1fK"
1503 " maximum_desired_capacity: %.1fK",
1504 MetaspaceSize / (double) K,
1505 maximum_desired_capacity / (double) K);
1506 gclog_or_tty->print_cr(" "
1507 " shrink_bytes: %.1fK"
1508 " current_shrink_factor: %d"
1509 " new shrink factor: %d"
1510 " MinMetaspaceExpansion: %.1fK",
1511 shrink_bytes / (double) K,
1512 current_shrink_factor,
1513 _shrink_factor,
1514 MinMetaspaceExpansion / (double) K);
1515 }
1516 }
1517 }
1518
1519 // Don't shrink unless it's significant
1520 if (shrink_bytes >= MinMetaspaceExpansion &&
1521 ((capacity_until_GC - shrink_bytes) >= MetaspaceSize)) {
1522 MetaspaceGC::set_capacity_until_GC(capacity_until_GC - shrink_bytes);
1523 }
1524 }
1525
1526 // Metadebug methods
1527
1528 void Metadebug::deallocate_chunk_a_lot(SpaceManager* sm,
1529 size_t chunk_word_size){
1530 #ifdef ASSERT
1531 VirtualSpaceList* vsl = sm->vs_list();
1532 if (MetaDataDeallocateALot &&
1533 Metadebug::deallocate_chunk_a_lot_count() % MetaDataDeallocateALotInterval == 0 ) {
1534 Metadebug::reset_deallocate_chunk_a_lot_count();
1535 for (uint i = 0; i < metadata_deallocate_a_lock_chunk; i++) {
1536 Metachunk* dummy_chunk = vsl->current_virtual_space()->take_from_committed(chunk_word_size);
1537 if (dummy_chunk == NULL) {
1538 break;
1539 }
1540 vsl->chunk_manager()->chunk_freelist_deallocate(dummy_chunk);
1541
1542 if (TraceMetadataChunkAllocation && Verbose) {
1543 gclog_or_tty->print("Metadebug::deallocate_chunk_a_lot: %d) ",
1544 sm->sum_count_in_chunks_in_use());
1545 dummy_chunk->print_on(gclog_or_tty);
1546 gclog_or_tty->print_cr(" Free chunks total %d count %d",
1547 vsl->chunk_manager()->free_chunks_total_words(),
1548 vsl->chunk_manager()->free_chunks_count());
1549 }
1550 }
1551 } else {
1552 Metadebug::inc_deallocate_chunk_a_lot_count();
1553 }
1554 #endif
1555 }
1556
1557 void Metadebug::deallocate_block_a_lot(SpaceManager* sm,
1558 size_t raw_word_size){
1559 #ifdef ASSERT
1560 if (MetaDataDeallocateALot &&
1561 Metadebug::deallocate_block_a_lot_count() % MetaDataDeallocateALotInterval == 0 ) {
1562 Metadebug::set_deallocate_block_a_lot_count(0);
1563 for (uint i = 0; i < metadata_deallocate_a_lot_block; i++) {
1564 MetaWord* dummy_block = sm->allocate_work(raw_word_size);
1565 if (dummy_block == 0) {
1566 break;
1567 }
1568 sm->deallocate(dummy_block, raw_word_size);
1569 }
1570 } else {
1571 Metadebug::inc_deallocate_block_a_lot_count();
1572 }
1573 #endif
1574 }
1575
1576 void Metadebug::init_allocation_fail_alot_count() {
1577 if (MetadataAllocationFailALot) {
1578 _allocation_fail_alot_count =
1579 1+(long)((double)MetadataAllocationFailALotInterval*os::random()/(max_jint+1.0));
1580 }
1581 }
1582
1583 #ifdef ASSERT
1584 bool Metadebug::test_metadata_failure() {
1585 if (MetadataAllocationFailALot &&
1586 Threads::is_vm_complete()) {
1587 if (_allocation_fail_alot_count > 0) {
1588 _allocation_fail_alot_count--;
1589 } else {
1590 if (TraceMetadataChunkAllocation && Verbose) {
1591 gclog_or_tty->print_cr("Metadata allocation failing for "
1592 "MetadataAllocationFailALot");
1593 }
1594 init_allocation_fail_alot_count();
1595 return true;
1596 }
1597 }
1598 return false;
1599 }
1600 #endif
1601
1602 // ChunkManager methods
1603
1604 size_t ChunkManager::free_chunks_total_words() {
1605 return _free_chunks_total;
1606 }
1607
1608 size_t ChunkManager::free_chunks_total_bytes() {
1609 return free_chunks_total_words() * BytesPerWord;
1610 }
1611
1612 size_t ChunkManager::free_chunks_count() {
1613 #ifdef ASSERT
1614 if (!UseConcMarkSweepGC && !SpaceManager::expand_lock()->is_locked()) {
1615 MutexLockerEx cl(SpaceManager::expand_lock(),
1616 Mutex::_no_safepoint_check_flag);
1617 // This lock is only needed in debug because the verification
1618 // of the _free_chunks_totals walks the list of free chunks
1619 slow_locked_verify_free_chunks_count();
1620 }
1621 #endif
1622 return _free_chunks_count;
1623 }
1624
1625 void ChunkManager::locked_verify_free_chunks_total() {
1626 assert_lock_strong(SpaceManager::expand_lock());
1627 assert(sum_free_chunks() == _free_chunks_total,
1628 err_msg("_free_chunks_total " SIZE_FORMAT " is not the"
1629 " same as sum " SIZE_FORMAT, _free_chunks_total,
1630 sum_free_chunks()));
1631 }
1632
1633 void ChunkManager::verify_free_chunks_total() {
1634 MutexLockerEx cl(SpaceManager::expand_lock(),
1635 Mutex::_no_safepoint_check_flag);
1636 locked_verify_free_chunks_total();
1637 }
1638
1639 void ChunkManager::locked_verify_free_chunks_count() {
1640 assert_lock_strong(SpaceManager::expand_lock());
1641 assert(sum_free_chunks_count() == _free_chunks_count,
1642 err_msg("_free_chunks_count " SIZE_FORMAT " is not the"
1643 " same as sum " SIZE_FORMAT, _free_chunks_count,
1644 sum_free_chunks_count()));
1645 }
1646
1647 void ChunkManager::verify_free_chunks_count() {
1648 #ifdef ASSERT
1649 MutexLockerEx cl(SpaceManager::expand_lock(),
1650 Mutex::_no_safepoint_check_flag);
1651 locked_verify_free_chunks_count();
1652 #endif
1653 }
1654
1655 void ChunkManager::verify() {
1656 MutexLockerEx cl(SpaceManager::expand_lock(),
1657 Mutex::_no_safepoint_check_flag);
1658 locked_verify();
1659 }
1660
1661 void ChunkManager::locked_verify() {
1662 locked_verify_free_chunks_count();
1663 locked_verify_free_chunks_total();
1664 }
1665
1666 void ChunkManager::locked_print_free_chunks(outputStream* st) {
1667 assert_lock_strong(SpaceManager::expand_lock());
1668 st->print_cr("Free chunk total " SIZE_FORMAT " count " SIZE_FORMAT,
1669 _free_chunks_total, _free_chunks_count);
1670 }
1671
1672 void ChunkManager::locked_print_sum_free_chunks(outputStream* st) {
1673 assert_lock_strong(SpaceManager::expand_lock());
1674 st->print_cr("Sum free chunk total " SIZE_FORMAT " count " SIZE_FORMAT,
1675 sum_free_chunks(), sum_free_chunks_count());
1676 }
1677 ChunkList* ChunkManager::free_chunks(ChunkIndex index) {
1678 return &_free_chunks[index];
1679 }
1680
1681 // These methods that sum the free chunk lists are used in printing
1682 // methods that are used in product builds.
1683 size_t ChunkManager::sum_free_chunks() {
1684 assert_lock_strong(SpaceManager::expand_lock());
1685 size_t result = 0;
1686 for (ChunkIndex i = ZeroIndex; i < NumberOfFreeLists; i = next_chunk_index(i)) {
1687 ChunkList* list = free_chunks(i);
1688
1689 if (list == NULL) {
1690 continue;
1691 }
1692
1693 result = result + list->count() * list->size();
1694 }
1695 result = result + humongous_dictionary()->total_size();
1696 return result;
1697 }
1698
1699 size_t ChunkManager::sum_free_chunks_count() {
1700 assert_lock_strong(SpaceManager::expand_lock());
1701 size_t count = 0;
1702 for (ChunkIndex i = ZeroIndex; i < NumberOfFreeLists; i = next_chunk_index(i)) {
1703 ChunkList* list = free_chunks(i);
1704 if (list == NULL) {
1705 continue;
1706 }
1707 count = count + list->count();
1708 }
1709 count = count + humongous_dictionary()->total_free_blocks();
1710 return count;
1711 }
1712
1713 ChunkList* ChunkManager::find_free_chunks_list(size_t word_size) {
1714 ChunkIndex index = list_index(word_size);
1715 assert(index < HumongousIndex, "No humongous list");
1716 return free_chunks(index);
1717 }
1718
1719 void ChunkManager::free_chunks_put(Metachunk* chunk) {
1720 assert_lock_strong(SpaceManager::expand_lock());
1721 ChunkList* free_list = find_free_chunks_list(chunk->word_size());
1722 chunk->set_next(free_list->head());
1723 free_list->set_head(chunk);
1724 // chunk is being returned to the chunk free list
1725 inc_free_chunks_total(chunk->capacity_word_size());
1726 slow_locked_verify();
1727 }
1728
1729 void ChunkManager::chunk_freelist_deallocate(Metachunk* chunk) {
1730 // The deallocation of a chunk originates in the freelist
1731 // manangement code for a Metaspace and does not hold the
1732 // lock.
1733 assert(chunk != NULL, "Deallocating NULL");
1734 assert_lock_strong(SpaceManager::expand_lock());
1735 slow_locked_verify();
1736 if (TraceMetadataChunkAllocation) {
1737 gclog_or_tty->print_cr("ChunkManager::chunk_freelist_deallocate: chunk "
1738 PTR_FORMAT " size " SIZE_FORMAT,
1739 chunk, chunk->word_size());
1740 }
1741 free_chunks_put(chunk);
1742 }
1743
1744 Metachunk* ChunkManager::free_chunks_get(size_t word_size) {
1745 assert_lock_strong(SpaceManager::expand_lock());
1746
1747 slow_locked_verify();
1748
1749 Metachunk* chunk = NULL;
1750 if (list_index(word_size) != HumongousIndex) {
1751 ChunkList* free_list = find_free_chunks_list(word_size);
1752 assert(free_list != NULL, "Sanity check");
1753
1754 chunk = free_list->head();
1755 debug_only(Metachunk* debug_head = chunk;)
1756
1757 if (chunk == NULL) {
1758 return NULL;
1759 }
1760
1761 // Remove the chunk as the head of the list.
1762 free_list->remove_chunk(chunk);
1763
1764 // Chunk is being removed from the chunks free list.
1765 dec_free_chunks_total(chunk->capacity_word_size());
1766
1767 if (TraceMetadataChunkAllocation && Verbose) {
1768 gclog_or_tty->print_cr("ChunkManager::free_chunks_get: free_list "
1769 PTR_FORMAT " head " PTR_FORMAT " size " SIZE_FORMAT,
1770 free_list, chunk, chunk->word_size());
1771 }
1772 } else {
1773 chunk = humongous_dictionary()->get_chunk(
1774 word_size,
1775 FreeBlockDictionary<Metachunk>::atLeast);
1776
1777 if (chunk != NULL) {
1778 if (TraceMetadataHumongousAllocation) {
1779 size_t waste = chunk->word_size() - word_size;
1780 gclog_or_tty->print_cr("Free list allocate humongous chunk size "
1781 SIZE_FORMAT " for requested size " SIZE_FORMAT
1782 " waste " SIZE_FORMAT,
1783 chunk->word_size(), word_size, waste);
1784 }
1785 // Chunk is being removed from the chunks free list.
1786 dec_free_chunks_total(chunk->capacity_word_size());
1787 } else {
1788 return NULL;
1789 }
1790 }
1791
1792 // Remove it from the links to this freelist
1793 chunk->set_next(NULL);
1794 chunk->set_prev(NULL);
1795 #ifdef ASSERT
1796 // Chunk is no longer on any freelist. Setting to false make container_count_slow()
1797 // work.
1798 chunk->set_is_free(false);
1799 #endif
1800 slow_locked_verify();
1801 return chunk;
1802 }
1803
1804 Metachunk* ChunkManager::chunk_freelist_allocate(size_t word_size) {
1805 assert_lock_strong(SpaceManager::expand_lock());
1806 slow_locked_verify();
1807
1808 // Take from the beginning of the list
1809 Metachunk* chunk = free_chunks_get(word_size);
1810 if (chunk == NULL) {
1811 return NULL;
1812 }
1813
1814 assert((word_size <= chunk->word_size()) ||
1815 list_index(chunk->word_size() == HumongousIndex),
1816 "Non-humongous variable sized chunk");
1817 if (TraceMetadataChunkAllocation) {
1818 size_t list_count;
1819 if (list_index(word_size) < HumongousIndex) {
1820 ChunkList* list = find_free_chunks_list(word_size);
1821 list_count = list->count();
1822 } else {
1823 list_count = humongous_dictionary()->total_count();
1824 }
1825 gclog_or_tty->print("ChunkManager::chunk_freelist_allocate: " PTR_FORMAT " chunk "
1826 PTR_FORMAT " size " SIZE_FORMAT " count " SIZE_FORMAT " ",
1827 this, chunk, chunk->word_size(), list_count);
1828 locked_print_free_chunks(gclog_or_tty);
1829 }
1830
1831 return chunk;
1832 }
1833
1834 void ChunkManager::print_on(outputStream* out) {
1835 if (PrintFLSStatistics != 0) {
1836 humongous_dictionary()->report_statistics();
1837 }
1838 }
1839
1840 // SpaceManager methods
1841
1842 void SpaceManager::get_initial_chunk_sizes(Metaspace::MetaspaceType type,
1843 size_t* chunk_word_size,
1844 size_t* class_chunk_word_size) {
1845 switch (type) {
1846 case Metaspace::BootMetaspaceType:
1847 *chunk_word_size = Metaspace::first_chunk_word_size();
1848 *class_chunk_word_size = Metaspace::first_class_chunk_word_size();
1849 break;
1850 case Metaspace::ROMetaspaceType:
1851 *chunk_word_size = SharedReadOnlySize / wordSize;
1852 *class_chunk_word_size = ClassSpecializedChunk;
1853 break;
1854 case Metaspace::ReadWriteMetaspaceType:
1855 *chunk_word_size = SharedReadWriteSize / wordSize;
1856 *class_chunk_word_size = ClassSpecializedChunk;
1857 break;
1858 case Metaspace::AnonymousMetaspaceType:
1859 case Metaspace::ReflectionMetaspaceType:
1860 *chunk_word_size = SpecializedChunk;
1861 *class_chunk_word_size = ClassSpecializedChunk;
1862 break;
1863 default:
1864 *chunk_word_size = SmallChunk;
1865 *class_chunk_word_size = ClassSmallChunk;
1866 break;
1867 }
1868 assert(*chunk_word_size != 0 && *class_chunk_word_size != 0,
1869 err_msg("Initial chunks sizes bad: data " SIZE_FORMAT
1870 " class " SIZE_FORMAT,
1871 *chunk_word_size, *class_chunk_word_size));
1872 }
1873
1874 size_t SpaceManager::sum_free_in_chunks_in_use() const {
1875 MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag);
1876 size_t free = 0;
1877 for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) {
1878 Metachunk* chunk = chunks_in_use(i);
1879 while (chunk != NULL) {
1880 free += chunk->free_word_size();
1881 chunk = chunk->next();
1882 }
1883 }
1884 return free;
1885 }
1886
1887 size_t SpaceManager::sum_waste_in_chunks_in_use() const {
1888 MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag);
1889 size_t result = 0;
1890 for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) {
1891 result += sum_waste_in_chunks_in_use(i);
1892 }
1893
1894 return result;
1895 }
1896
1897 size_t SpaceManager::sum_waste_in_chunks_in_use(ChunkIndex index) const {
1898 size_t result = 0;
1899 Metachunk* chunk = chunks_in_use(index);
1900 // Count the free space in all the chunk but not the
1901 // current chunk from which allocations are still being done.
1902 while (chunk != NULL) {
1903 if (chunk != current_chunk()) {
1904 result += chunk->free_word_size();
1905 }
1906 chunk = chunk->next();
1907 }
1908 return result;
1909 }
1910
1911 size_t SpaceManager::sum_capacity_in_chunks_in_use() const {
1912 // For CMS use "allocated_chunks_words()" which does not need the
1913 // Metaspace lock. For the other collectors sum over the
1914 // lists. Use both methods as a check that "allocated_chunks_words()"
1915 // is correct. That is, sum_capacity_in_chunks() is too expensive
1916 // to use in the product and allocated_chunks_words() should be used
1917 // but allow for checking that allocated_chunks_words() returns the same
1918 // value as sum_capacity_in_chunks_in_use() which is the definitive
1919 // answer.
1920 if (UseConcMarkSweepGC) {
1921 return allocated_chunks_words();
1922 } else {
1923 MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag);
1924 size_t sum = 0;
1925 for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) {
1926 Metachunk* chunk = chunks_in_use(i);
1927 while (chunk != NULL) {
1928 sum += chunk->capacity_word_size();
1929 chunk = chunk->next();
1930 }
1931 }
1932 return sum;
1933 }
1934 }
1935
1936 size_t SpaceManager::sum_count_in_chunks_in_use() {
1937 size_t count = 0;
1938 for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) {
1939 count = count + sum_count_in_chunks_in_use(i);
1940 }
1941
1942 return count;
1943 }
1944
1945 size_t SpaceManager::sum_count_in_chunks_in_use(ChunkIndex i) {
1946 size_t count = 0;
1947 Metachunk* chunk = chunks_in_use(i);
1948 while (chunk != NULL) {
1949 count++;
1950 chunk = chunk->next();
1951 }
1952 return count;
1953 }
1954
1955
1956 size_t SpaceManager::sum_used_in_chunks_in_use() const {
1957 MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag);
1958 size_t used = 0;
1959 for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) {
1960 Metachunk* chunk = chunks_in_use(i);
1961 while (chunk != NULL) {
1962 used += chunk->used_word_size();
1963 chunk = chunk->next();
1964 }
1965 }
1966 return used;
1967 }
1968
1969 void SpaceManager::locked_print_chunks_in_use_on(outputStream* st) const {
1970
1971 for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) {
1972 Metachunk* chunk = chunks_in_use(i);
1973 st->print("SpaceManager: %s " PTR_FORMAT,
1974 chunk_size_name(i), chunk);
1975 if (chunk != NULL) {
1976 st->print_cr(" free " SIZE_FORMAT,
1977 chunk->free_word_size());
1978 } else {
1979 st->print_cr("");
1980 }
1981 }
1982
1983 vs_list()->chunk_manager()->locked_print_free_chunks(st);
1984 vs_list()->chunk_manager()->locked_print_sum_free_chunks(st);
1985 }
1986
1987 size_t SpaceManager::calc_chunk_size(size_t word_size) {
1988
1989 // Decide between a small chunk and a medium chunk. Up to
1990 // _small_chunk_limit small chunks can be allocated but
1991 // once a medium chunk has been allocated, no more small
1992 // chunks will be allocated.
1993 size_t chunk_word_size;
1994 if (chunks_in_use(MediumIndex) == NULL &&
1995 sum_count_in_chunks_in_use(SmallIndex) < _small_chunk_limit) {
1996 chunk_word_size = (size_t) small_chunk_size();
1997 if (word_size + Metachunk::overhead() > small_chunk_size()) {
1998 chunk_word_size = medium_chunk_size();
1999 }
2000 } else {
2001 chunk_word_size = medium_chunk_size();
2002 }
2003
2004 // Might still need a humongous chunk. Enforce an
2005 // eight word granularity to facilitate reuse (some
2006 // wastage but better chance of reuse).
2007 size_t if_humongous_sized_chunk =
2008 align_size_up(word_size + Metachunk::overhead(),
2009 HumongousChunkGranularity);
2010 chunk_word_size =
2011 MAX2((size_t) chunk_word_size, if_humongous_sized_chunk);
2012
2013 assert(!SpaceManager::is_humongous(word_size) ||
2014 chunk_word_size == if_humongous_sized_chunk,
2015 err_msg("Size calculation is wrong, word_size " SIZE_FORMAT
2016 " chunk_word_size " SIZE_FORMAT,
2017 word_size, chunk_word_size));
2018 if (TraceMetadataHumongousAllocation &&
2019 SpaceManager::is_humongous(word_size)) {
2020 gclog_or_tty->print_cr("Metadata humongous allocation:");
2021 gclog_or_tty->print_cr(" word_size " PTR_FORMAT, word_size);
2022 gclog_or_tty->print_cr(" chunk_word_size " PTR_FORMAT,
2023 chunk_word_size);
2024 gclog_or_tty->print_cr(" chunk overhead " PTR_FORMAT,
2025 Metachunk::overhead());
2026 }
2027 return chunk_word_size;
2028 }
2029
2030 MetaWord* SpaceManager::grow_and_allocate(size_t word_size) {
2031 assert(vs_list()->current_virtual_space() != NULL,
2032 "Should have been set");
2033 assert(current_chunk() == NULL ||
2034 current_chunk()->allocate(word_size) == NULL,
2035 "Don't need to expand");
2036 MutexLockerEx cl(SpaceManager::expand_lock(), Mutex::_no_safepoint_check_flag);
2037
2038 if (TraceMetadataChunkAllocation && Verbose) {
2039 size_t words_left = 0;
2040 size_t words_used = 0;
2041 if (current_chunk() != NULL) {
2042 words_left = current_chunk()->free_word_size();
2043 words_used = current_chunk()->used_word_size();
2044 }
2045 gclog_or_tty->print_cr("SpaceManager::grow_and_allocate for " SIZE_FORMAT
2046 " words " SIZE_FORMAT " words used " SIZE_FORMAT
2047 " words left",
2048 word_size, words_used, words_left);
2049 }
2050
2051 // Get another chunk out of the virtual space
2052 size_t grow_chunks_by_words = calc_chunk_size(word_size);
2053 Metachunk* next = get_new_chunk(word_size, grow_chunks_by_words);
2054
2055 // If a chunk was available, add it to the in-use chunk list
2056 // and do an allocation from it.
2057 if (next != NULL) {
2058 Metadebug::deallocate_chunk_a_lot(this, grow_chunks_by_words);
2059 // Add to this manager's list of chunks in use.
2060 add_chunk(next, false);
2061 return next->allocate(word_size);
2062 }
2063 return NULL;
2064 }
2065
2066 void SpaceManager::print_on(outputStream* st) const {
2067
2068 for (ChunkIndex i = ZeroIndex;
2069 i < NumberOfInUseLists ;
2070 i = next_chunk_index(i) ) {
2071 st->print_cr(" chunks_in_use " PTR_FORMAT " chunk size " PTR_FORMAT,
2072 chunks_in_use(i),
2073 chunks_in_use(i) == NULL ? 0 : chunks_in_use(i)->word_size());
2074 }
2075 st->print_cr(" waste: Small " SIZE_FORMAT " Medium " SIZE_FORMAT
2076 " Humongous " SIZE_FORMAT,
2077 sum_waste_in_chunks_in_use(SmallIndex),
2078 sum_waste_in_chunks_in_use(MediumIndex),
2079 sum_waste_in_chunks_in_use(HumongousIndex));
2080 // block free lists
2081 if (block_freelists() != NULL) {
2082 st->print_cr("total in block free lists " SIZE_FORMAT,
2083 block_freelists()->total_size());
2084 }
2085 }
2086
2087 SpaceManager::SpaceManager(Metaspace::MetadataType mdtype,
2088 Mutex* lock,
2089 VirtualSpaceList* vs_list) :
2090 _vs_list(vs_list),
2091 _mdtype(mdtype),
2092 _allocated_blocks_words(0),
2093 _allocated_chunks_words(0),
2094 _allocated_chunks_count(0),
2095 _lock(lock)
2096 {
2097 initialize();
2098 }
2099
2100 void SpaceManager::inc_size_metrics(size_t words) {
2101 assert_lock_strong(SpaceManager::expand_lock());
2102 // Total of allocated Metachunks and allocated Metachunks count
2103 // for each SpaceManager
2104 _allocated_chunks_words = _allocated_chunks_words + words;
2105 _allocated_chunks_count++;
2106 // Global total of capacity in allocated Metachunks
2107 MetaspaceAux::inc_capacity(mdtype(), words);
2108 // Global total of allocated Metablocks.
2109 // used_words_slow() includes the overhead in each
2110 // Metachunk so include it in the used when the
2111 // Metachunk is first added (so only added once per
2112 // Metachunk).
2113 MetaspaceAux::inc_used(mdtype(), Metachunk::overhead());
2114 }
2115
2116 void SpaceManager::inc_used_metrics(size_t words) {
2117 // Add to the per SpaceManager total
2118 Atomic::add_ptr(words, &_allocated_blocks_words);
2119 // Add to the global total
2120 MetaspaceAux::inc_used(mdtype(), words);
2121 }
2122
2123 void SpaceManager::dec_total_from_size_metrics() {
2124 MetaspaceAux::dec_capacity(mdtype(), allocated_chunks_words());
2125 MetaspaceAux::dec_used(mdtype(), allocated_blocks_words());
2126 // Also deduct the overhead per Metachunk
2127 MetaspaceAux::dec_used(mdtype(), allocated_chunks_count() * Metachunk::overhead());
2128 }
2129
2130 void SpaceManager::initialize() {
2131 Metadebug::init_allocation_fail_alot_count();
2132 for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) {
2133 _chunks_in_use[i] = NULL;
2134 }
2135 _current_chunk = NULL;
2136 if (TraceMetadataChunkAllocation && Verbose) {
2137 gclog_or_tty->print_cr("SpaceManager(): " PTR_FORMAT, this);
2138 }
2139 }
2140
2141 void ChunkManager::return_chunks(ChunkIndex index, Metachunk* chunks) {
2142 if (chunks == NULL) {
2143 return;
2144 }
2145 ChunkList* list = free_chunks(index);
2146 assert(list->size() == chunks->word_size(), "Mismatch in chunk sizes");
2147 assert_lock_strong(SpaceManager::expand_lock());
2148 Metachunk* cur = chunks;
2149
2150 // This returns chunks one at a time. If a new
2151 // class List can be created that is a base class
2152 // of FreeList then something like FreeList::prepend()
2153 // can be used in place of this loop
2154 while (cur != NULL) {
2155 assert(cur->container() != NULL, "Container should have been set");
2156 cur->container()->dec_container_count();
2157 // Capture the next link before it is changed
2158 // by the call to return_chunk_at_head();
2159 Metachunk* next = cur->next();
2160 cur->set_is_free(true);
2161 list->return_chunk_at_head(cur);
2162 cur = next;
2163 }
2164 }
2165
2166 SpaceManager::~SpaceManager() {
2167 // This call this->_lock which can't be done while holding expand_lock()
2168 assert(sum_capacity_in_chunks_in_use() == allocated_chunks_words(),
2169 err_msg("sum_capacity_in_chunks_in_use() " SIZE_FORMAT
2170 " allocated_chunks_words() " SIZE_FORMAT,
2171 sum_capacity_in_chunks_in_use(), allocated_chunks_words()));
2172
2173 MutexLockerEx fcl(SpaceManager::expand_lock(),
2174 Mutex::_no_safepoint_check_flag);
2175
2176 ChunkManager* chunk_manager = vs_list()->chunk_manager();
2177
2178 chunk_manager->slow_locked_verify();
2179
2180 dec_total_from_size_metrics();
2181
2182 if (TraceMetadataChunkAllocation && Verbose) {
2183 gclog_or_tty->print_cr("~SpaceManager(): " PTR_FORMAT, this);
2184 locked_print_chunks_in_use_on(gclog_or_tty);
2185 }
2186
2187 // Do not mangle freed Metachunks. The chunk size inside Metachunks
2188 // is during the freeing of a VirtualSpaceNodes.
2189
2190 // Have to update before the chunks_in_use lists are emptied
2191 // below.
2192 chunk_manager->inc_free_chunks_total(allocated_chunks_words(),
2193 sum_count_in_chunks_in_use());
2194
2195 // Add all the chunks in use by this space manager
2196 // to the global list of free chunks.
2197
2198 // Follow each list of chunks-in-use and add them to the
2199 // free lists. Each list is NULL terminated.
2200
2201 for (ChunkIndex i = ZeroIndex; i < HumongousIndex; i = next_chunk_index(i)) {
2202 if (TraceMetadataChunkAllocation && Verbose) {
2203 gclog_or_tty->print_cr("returned %d %s chunks to freelist",
2204 sum_count_in_chunks_in_use(i),
2205 chunk_size_name(i));
2206 }
2207 Metachunk* chunks = chunks_in_use(i);
2208 chunk_manager->return_chunks(i, chunks);
2209 set_chunks_in_use(i, NULL);
2210 if (TraceMetadataChunkAllocation && Verbose) {
2211 gclog_or_tty->print_cr("updated freelist count %d %s",
2212 chunk_manager->free_chunks(i)->count(),
2213 chunk_size_name(i));
2214 }
2215 assert(i != HumongousIndex, "Humongous chunks are handled explicitly later");
2216 }
2217
2218 // The medium chunk case may be optimized by passing the head and
2219 // tail of the medium chunk list to add_at_head(). The tail is often
2220 // the current chunk but there are probably exceptions.
2221
2222 // Humongous chunks
2223 if (TraceMetadataChunkAllocation && Verbose) {
2224 gclog_or_tty->print_cr("returned %d %s humongous chunks to dictionary",
2225 sum_count_in_chunks_in_use(HumongousIndex),
2226 chunk_size_name(HumongousIndex));
2227 gclog_or_tty->print("Humongous chunk dictionary: ");
2228 }
2229 // Humongous chunks are never the current chunk.
2230 Metachunk* humongous_chunks = chunks_in_use(HumongousIndex);
2231
2232 while (humongous_chunks != NULL) {
2233 #ifdef ASSERT
2234 humongous_chunks->set_is_free(true);
2235 #endif
2236 if (TraceMetadataChunkAllocation && Verbose) {
2237 gclog_or_tty->print(PTR_FORMAT " (" SIZE_FORMAT ") ",
2238 humongous_chunks,
2239 humongous_chunks->word_size());
2240 }
2241 assert(humongous_chunks->word_size() == (size_t)
2242 align_size_up(humongous_chunks->word_size(),
2243 HumongousChunkGranularity),
2244 err_msg("Humongous chunk size is wrong: word size " SIZE_FORMAT
2245 " granularity %d",
2246 humongous_chunks->word_size(), HumongousChunkGranularity));
2247 Metachunk* next_humongous_chunks = humongous_chunks->next();
2248 humongous_chunks->container()->dec_container_count();
2249 chunk_manager->humongous_dictionary()->return_chunk(humongous_chunks);
2250 humongous_chunks = next_humongous_chunks;
2251 }
2252 if (TraceMetadataChunkAllocation && Verbose) {
2253 gclog_or_tty->print_cr("");
2254 gclog_or_tty->print_cr("updated dictionary count %d %s",
2255 chunk_manager->humongous_dictionary()->total_count(),
2256 chunk_size_name(HumongousIndex));
2257 }
2258 chunk_manager->slow_locked_verify();
2259 }
2260
2261 const char* SpaceManager::chunk_size_name(ChunkIndex index) const {
2262 switch (index) {
2263 case SpecializedIndex:
2264 return "Specialized";
2265 case SmallIndex:
2266 return "Small";
2267 case MediumIndex:
2268 return "Medium";
2269 case HumongousIndex:
2270 return "Humongous";
2271 default:
2272 return NULL;
2273 }
2274 }
2275
2276 ChunkIndex ChunkManager::list_index(size_t size) {
2277 switch (size) {
2278 case SpecializedChunk:
2279 assert(SpecializedChunk == ClassSpecializedChunk,
2280 "Need branch for ClassSpecializedChunk");
2281 return SpecializedIndex;
2282 case SmallChunk:
2283 case ClassSmallChunk:
2284 return SmallIndex;
2285 case MediumChunk:
2286 case ClassMediumChunk:
2287 return MediumIndex;
2288 default:
2289 assert(size > MediumChunk || size > ClassMediumChunk,
2290 "Not a humongous chunk");
2291 return HumongousIndex;
2292 }
2293 }
2294
2295 void SpaceManager::deallocate(MetaWord* p, size_t word_size) {
2296 assert_lock_strong(_lock);
2297 size_t raw_word_size = get_raw_word_size(word_size);
2298 size_t min_size = TreeChunk<Metablock, FreeList>::min_size();
2299 assert(raw_word_size >= min_size,
2300 err_msg("Should not deallocate dark matter " SIZE_FORMAT "<" SIZE_FORMAT, word_size, min_size));
2301 block_freelists()->return_block(p, raw_word_size);
2302 }
2303
2304 // Adds a chunk to the list of chunks in use.
2305 void SpaceManager::add_chunk(Metachunk* new_chunk, bool make_current) {
2306
2307 assert(new_chunk != NULL, "Should not be NULL");
2308 assert(new_chunk->next() == NULL, "Should not be on a list");
2309
2310 new_chunk->reset_empty();
2311
2312 // Find the correct list and and set the current
2313 // chunk for that list.
2314 ChunkIndex index = ChunkManager::list_index(new_chunk->word_size());
2315
2316 if (index != HumongousIndex) {
2317 retire_current_chunk();
2318 set_current_chunk(new_chunk);
2319 new_chunk->set_next(chunks_in_use(index));
2320 set_chunks_in_use(index, new_chunk);
2321 } else {
2322 // For null class loader data and DumpSharedSpaces, the first chunk isn't
2323 // small, so small will be null. Link this first chunk as the current
2324 // chunk.
2325 if (make_current) {
2326 // Set as the current chunk but otherwise treat as a humongous chunk.
2327 set_current_chunk(new_chunk);
2328 }
2329 // Link at head. The _current_chunk only points to a humongous chunk for
2330 // the null class loader metaspace (class and data virtual space managers)
2331 // any humongous chunks so will not point to the tail
2332 // of the humongous chunks list.
2333 new_chunk->set_next(chunks_in_use(HumongousIndex));
2334 set_chunks_in_use(HumongousIndex, new_chunk);
2335
2336 assert(new_chunk->word_size() > medium_chunk_size(), "List inconsistency");
2337 }
2338
2339 // Add to the running sum of capacity
2340 inc_size_metrics(new_chunk->word_size());
2341
2342 assert(new_chunk->is_empty(), "Not ready for reuse");
2343 if (TraceMetadataChunkAllocation && Verbose) {
2344 gclog_or_tty->print("SpaceManager::add_chunk: %d) ",
2345 sum_count_in_chunks_in_use());
2346 new_chunk->print_on(gclog_or_tty);
2347 if (vs_list() != NULL) {
2348 vs_list()->chunk_manager()->locked_print_free_chunks(gclog_or_tty);
2349 }
2350 }
2351 }
2352
2353 void SpaceManager::retire_current_chunk() {
2354 if (current_chunk() != NULL) {
2355 size_t remaining_words = current_chunk()->free_word_size();
2356 if (remaining_words >= TreeChunk<Metablock, FreeList>::min_size()) {
2357 block_freelists()->return_block(current_chunk()->allocate(remaining_words), remaining_words);
2358 inc_used_metrics(remaining_words);
2359 }
2360 }
2361 }
2362
2363 Metachunk* SpaceManager::get_new_chunk(size_t word_size,
2364 size_t grow_chunks_by_words) {
2365
2366 Metachunk* next = vs_list()->get_new_chunk(word_size,
2367 grow_chunks_by_words,
2368 medium_chunk_bunch());
2369
2370 if (TraceMetadataHumongousAllocation && next != NULL &&
2371 SpaceManager::is_humongous(next->word_size())) {
2372 gclog_or_tty->print_cr(" new humongous chunk word size "
2373 PTR_FORMAT, next->word_size());
2374 }
2375
2376 return next;
2377 }
2378
2379 MetaWord* SpaceManager::allocate(size_t word_size) {
2380 MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag);
2381
2382 size_t raw_word_size = get_raw_word_size(word_size);
2383 BlockFreelist* fl = block_freelists();
2384 MetaWord* p = NULL;
2385 // Allocation from the dictionary is expensive in the sense that
2386 // the dictionary has to be searched for a size. Don't allocate
2387 // from the dictionary until it starts to get fat. Is this
2388 // a reasonable policy? Maybe an skinny dictionary is fast enough
2389 // for allocations. Do some profiling. JJJ
2390 if (fl->total_size() > allocation_from_dictionary_limit) {
2391 p = fl->get_block(raw_word_size);
2392 }
2393 if (p == NULL) {
2394 p = allocate_work(raw_word_size);
2395 }
2396 Metadebug::deallocate_block_a_lot(this, raw_word_size);
2397
2398 return p;
2399 }
2400
2401 // Returns the address of spaced allocated for "word_size".
2402 // This methods does not know about blocks (Metablocks)
2403 MetaWord* SpaceManager::allocate_work(size_t word_size) {
2404 assert_lock_strong(_lock);
2405 #ifdef ASSERT
2406 if (Metadebug::test_metadata_failure()) {
2407 return NULL;
2408 }
2409 #endif
2410 // Is there space in the current chunk?
2411 MetaWord* result = NULL;
2412
2413 // For DumpSharedSpaces, only allocate out of the current chunk which is
2414 // never null because we gave it the size we wanted. Caller reports out
2415 // of memory if this returns null.
2416 if (DumpSharedSpaces) {
2417 assert(current_chunk() != NULL, "should never happen");
2418 inc_used_metrics(word_size);
2419 return current_chunk()->allocate(word_size); // caller handles null result
2420 }
2421 if (current_chunk() != NULL) {
2422 result = current_chunk()->allocate(word_size);
2423 }
2424
2425 if (result == NULL) {
2426 result = grow_and_allocate(word_size);
2427 }
2428 if (result != 0) {
2429 inc_used_metrics(word_size);
2430 assert(result != (MetaWord*) chunks_in_use(MediumIndex),
2431 "Head of the list is being allocated");
2432 }
2433
2434 return result;
2435 }
2436
2437 void SpaceManager::verify() {
2438 // If there are blocks in the dictionary, then
2439 // verfication of chunks does not work since
2440 // being in the dictionary alters a chunk.
2441 if (block_freelists()->total_size() == 0) {
2442 for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) {
2443 Metachunk* curr = chunks_in_use(i);
2444 while (curr != NULL) {
2445 curr->verify();
2446 verify_chunk_size(curr);
2447 curr = curr->next();
2448 }
2449 }
2450 }
2451 }
2452
2453 void SpaceManager::verify_chunk_size(Metachunk* chunk) {
2454 assert(is_humongous(chunk->word_size()) ||
2455 chunk->word_size() == medium_chunk_size() ||
2456 chunk->word_size() == small_chunk_size() ||
2457 chunk->word_size() == specialized_chunk_size(),
2458 "Chunk size is wrong");
2459 return;
2460 }
2461
2462 #ifdef ASSERT
2463 void SpaceManager::verify_allocated_blocks_words() {
2464 // Verification is only guaranteed at a safepoint.
2465 assert(SafepointSynchronize::is_at_safepoint() || !Universe::is_fully_initialized(),
2466 "Verification can fail if the applications is running");
2467 assert(allocated_blocks_words() == sum_used_in_chunks_in_use(),
2468 err_msg("allocation total is not consistent " SIZE_FORMAT
2469 " vs " SIZE_FORMAT,
2470 allocated_blocks_words(), sum_used_in_chunks_in_use()));
2471 }
2472
2473 #endif
2474
2475 void SpaceManager::dump(outputStream* const out) const {
2476 size_t curr_total = 0;
2477 size_t waste = 0;
2478 uint i = 0;
2479 size_t used = 0;
2480 size_t capacity = 0;
2481
2482 // Add up statistics for all chunks in this SpaceManager.
2483 for (ChunkIndex index = ZeroIndex;
2484 index < NumberOfInUseLists;
2485 index = next_chunk_index(index)) {
2486 for (Metachunk* curr = chunks_in_use(index);
2487 curr != NULL;
2488 curr = curr->next()) {
2489 out->print("%d) ", i++);
2490 curr->print_on(out);
2491 curr_total += curr->word_size();
2492 used += curr->used_word_size();
2493 capacity += curr->capacity_word_size();
2494 waste += curr->free_word_size() + curr->overhead();;
2495 }
2496 }
2497
2498 if (TraceMetadataChunkAllocation && Verbose) {
2499 block_freelists()->print_on(out);
2500 }
2501
2502 size_t free = current_chunk() == NULL ? 0 : current_chunk()->free_word_size();
2503 // Free space isn't wasted.
2504 waste -= free;
2505
2506 out->print_cr("total of all chunks " SIZE_FORMAT " used " SIZE_FORMAT
2507 " free " SIZE_FORMAT " capacity " SIZE_FORMAT
2508 " waste " SIZE_FORMAT, curr_total, used, free, capacity, waste);
2509 }
2510
2511 #ifndef PRODUCT
2512 void SpaceManager::mangle_freed_chunks() {
2513 for (ChunkIndex index = ZeroIndex;
2514 index < NumberOfInUseLists;
2515 index = next_chunk_index(index)) {
2516 for (Metachunk* curr = chunks_in_use(index);
2517 curr != NULL;
2518 curr = curr->next()) {
2519 curr->mangle();
2520 }
2521 }
2522 }
2523 #endif // PRODUCT
2524
2525 // MetaspaceAux
2526
2527
2528 size_t MetaspaceAux::_allocated_capacity_words[] = {0, 0};
2529 size_t MetaspaceAux::_allocated_used_words[] = {0, 0};
2530
2531 size_t MetaspaceAux::free_bytes(Metaspace::MetadataType mdtype) {
2532 VirtualSpaceList* list = Metaspace::get_space_list(mdtype);
2533 return list == NULL ? 0 : list->free_bytes();
2534 }
2535
2536 size_t MetaspaceAux::free_bytes() {
2537 return free_bytes(Metaspace::ClassType) + free_bytes(Metaspace::NonClassType);
2538 }
2539
2540 void MetaspaceAux::dec_capacity(Metaspace::MetadataType mdtype, size_t words) {
2541 assert_lock_strong(SpaceManager::expand_lock());
2542 assert(words <= allocated_capacity_words(mdtype),
2543 err_msg("About to decrement below 0: words " SIZE_FORMAT
2544 " is greater than _allocated_capacity_words[%u] " SIZE_FORMAT,
2545 words, mdtype, allocated_capacity_words(mdtype)));
2546 _allocated_capacity_words[mdtype] -= words;
2547 }
2548
2549 void MetaspaceAux::inc_capacity(Metaspace::MetadataType mdtype, size_t words) {
2550 assert_lock_strong(SpaceManager::expand_lock());
2551 // Needs to be atomic
2552 _allocated_capacity_words[mdtype] += words;
2553 }
2554
2555 void MetaspaceAux::dec_used(Metaspace::MetadataType mdtype, size_t words) {
2556 assert(words <= allocated_used_words(mdtype),
2557 err_msg("About to decrement below 0: words " SIZE_FORMAT
2558 " is greater than _allocated_used_words[%u] " SIZE_FORMAT,
2559 words, mdtype, allocated_used_words(mdtype)));
2560 // For CMS deallocation of the Metaspaces occurs during the
2561 // sweep which is a concurrent phase. Protection by the expand_lock()
2562 // is not enough since allocation is on a per Metaspace basis
2563 // and protected by the Metaspace lock.
2564 jlong minus_words = (jlong) - (jlong) words;
2565 Atomic::add_ptr(minus_words, &_allocated_used_words[mdtype]);
2566 }
2567
2568 void MetaspaceAux::inc_used(Metaspace::MetadataType mdtype, size_t words) {
2569 // _allocated_used_words tracks allocations for
2570 // each piece of metadata. Those allocations are
2571 // generally done concurrently by different application
2572 // threads so must be done atomically.
2573 Atomic::add_ptr(words, &_allocated_used_words[mdtype]);
2574 }
2575
2576 size_t MetaspaceAux::used_bytes_slow(Metaspace::MetadataType mdtype) {
2577 size_t used = 0;
2578 ClassLoaderDataGraphMetaspaceIterator iter;
2579 while (iter.repeat()) {
2580 Metaspace* msp = iter.get_next();
2581 // Sum allocated_blocks_words for each metaspace
2582 if (msp != NULL) {
2583 used += msp->used_words_slow(mdtype);
2584 }
2585 }
2586 return used * BytesPerWord;
2587 }
2588
2589 size_t MetaspaceAux::free_bytes_slow(Metaspace::MetadataType mdtype) {
2590 size_t free = 0;
2591 ClassLoaderDataGraphMetaspaceIterator iter;
2592 while (iter.repeat()) {
2593 Metaspace* msp = iter.get_next();
2594 if (msp != NULL) {
2595 free += msp->free_words_slow(mdtype);
2596 }
2597 }
2598 return free * BytesPerWord;
2599 }
2600
2601 size_t MetaspaceAux::capacity_bytes_slow(Metaspace::MetadataType mdtype) {
2602 if ((mdtype == Metaspace::ClassType) && !Metaspace::using_class_space()) {
2603 return 0;
2604 }
2605 // Don't count the space in the freelists. That space will be
2606 // added to the capacity calculation as needed.
2607 size_t capacity = 0;
2608 ClassLoaderDataGraphMetaspaceIterator iter;
2609 while (iter.repeat()) {
2610 Metaspace* msp = iter.get_next();
2611 if (msp != NULL) {
2612 capacity += msp->capacity_words_slow(mdtype);
2613 }
2614 }
2615 return capacity * BytesPerWord;
2616 }
2617
2618 size_t MetaspaceAux::capacity_bytes_slow() {
2619 #ifdef PRODUCT
2620 // Use allocated_capacity_bytes() in PRODUCT instead of this function.
2621 guarantee(false, "Should not call capacity_bytes_slow() in the PRODUCT");
2622 #endif
2623 size_t class_capacity = capacity_bytes_slow(Metaspace::ClassType);
2624 size_t non_class_capacity = capacity_bytes_slow(Metaspace::NonClassType);
2625 assert(allocated_capacity_bytes() == class_capacity + non_class_capacity,
2626 err_msg("bad accounting: allocated_capacity_bytes() " SIZE_FORMAT
2627 " class_capacity + non_class_capacity " SIZE_FORMAT
2628 " class_capacity " SIZE_FORMAT " non_class_capacity " SIZE_FORMAT,
2629 allocated_capacity_bytes(), class_capacity + non_class_capacity,
2630 class_capacity, non_class_capacity));
2631
2632 return class_capacity + non_class_capacity;
2633 }
2634
2635 size_t MetaspaceAux::reserved_bytes(Metaspace::MetadataType mdtype) {
2636 VirtualSpaceList* list = Metaspace::get_space_list(mdtype);
2637 return list == NULL ? 0 : list->reserved_bytes();
2638 }
2639
2640 size_t MetaspaceAux::committed_bytes(Metaspace::MetadataType mdtype) {
2641 VirtualSpaceList* list = Metaspace::get_space_list(mdtype);
2642 return list == NULL ? 0 : list->committed_bytes();
2643 }
2644
2645 size_t MetaspaceAux::min_chunk_size_words() { return Metaspace::first_chunk_word_size(); }
2646
2647 size_t MetaspaceAux::free_chunks_total_words(Metaspace::MetadataType mdtype) {
2648 VirtualSpaceList* list = Metaspace::get_space_list(mdtype);
2649 if (list == NULL) {
2650 return 0;
2651 }
2652 ChunkManager* chunk = list->chunk_manager();
2653 chunk->slow_verify();
2654 return chunk->free_chunks_total_words();
2655 }
2656
2657 size_t MetaspaceAux::free_chunks_total_bytes(Metaspace::MetadataType mdtype) {
2658 return free_chunks_total_words(mdtype) * BytesPerWord;
2659 }
2660
2661 size_t MetaspaceAux::free_chunks_total_words() {
2662 return free_chunks_total_words(Metaspace::ClassType) +
2663 free_chunks_total_words(Metaspace::NonClassType);
2664 }
2665
2666 size_t MetaspaceAux::free_chunks_total_bytes() {
2667 return free_chunks_total_words() * BytesPerWord;
2668 }
2669
2670 void MetaspaceAux::print_metaspace_change(size_t prev_metadata_used) {
2671 gclog_or_tty->print(", [Metaspace:");
2672 if (PrintGCDetails && Verbose) {
2673 gclog_or_tty->print(" " SIZE_FORMAT
2674 "->" SIZE_FORMAT
2675 "(" SIZE_FORMAT ")",
2676 prev_metadata_used,
2677 allocated_used_bytes(),
2678 reserved_bytes());
2679 } else {
2680 gclog_or_tty->print(" " SIZE_FORMAT "K"
2681 "->" SIZE_FORMAT "K"
2682 "(" SIZE_FORMAT "K)",
2683 prev_metadata_used/K,
2684 allocated_used_bytes()/K,
2685 reserved_bytes()/K);
2686 }
2687
2688 gclog_or_tty->print("]");
2689 }
2690
2691 // This is printed when PrintGCDetails
2692 void MetaspaceAux::print_on(outputStream* out) {
2693 Metaspace::MetadataType nct = Metaspace::NonClassType;
2694
2695 out->print_cr(" Metaspace total "
2696 SIZE_FORMAT "K, used " SIZE_FORMAT "K,"
2697 " reserved " SIZE_FORMAT "K",
2698 allocated_capacity_bytes()/K, allocated_used_bytes()/K, reserved_bytes()/K);
2699
2700 out->print_cr(" data space "
2701 SIZE_FORMAT "K, used " SIZE_FORMAT "K,"
2702 " reserved " SIZE_FORMAT "K",
2703 allocated_capacity_bytes(nct)/K,
2704 allocated_used_bytes(nct)/K,
2705 reserved_bytes(nct)/K);
2706 if (Metaspace::using_class_space()) {
2707 Metaspace::MetadataType ct = Metaspace::ClassType;
2708 out->print_cr(" class space "
2709 SIZE_FORMAT "K, used " SIZE_FORMAT "K,"
2710 " reserved " SIZE_FORMAT "K",
2711 allocated_capacity_bytes(ct)/K,
2712 allocated_used_bytes(ct)/K,
2713 reserved_bytes(ct)/K);
2714 }
2715 }
2716
2717 // Print information for class space and data space separately.
2718 // This is almost the same as above.
2719 void MetaspaceAux::print_on(outputStream* out, Metaspace::MetadataType mdtype) {
2720 size_t free_chunks_capacity_bytes = free_chunks_total_bytes(mdtype);
2721 size_t capacity_bytes = capacity_bytes_slow(mdtype);
2722 size_t used_bytes = used_bytes_slow(mdtype);
2723 size_t free_bytes = free_bytes_slow(mdtype);
2724 size_t used_and_free = used_bytes + free_bytes +
2725 free_chunks_capacity_bytes;
2726 out->print_cr(" Chunk accounting: used in chunks " SIZE_FORMAT
2727 "K + unused in chunks " SIZE_FORMAT "K + "
2728 " capacity in free chunks " SIZE_FORMAT "K = " SIZE_FORMAT
2729 "K capacity in allocated chunks " SIZE_FORMAT "K",
2730 used_bytes / K,
2731 free_bytes / K,
2732 free_chunks_capacity_bytes / K,
2733 used_and_free / K,
2734 capacity_bytes / K);
2735 // Accounting can only be correct if we got the values during a safepoint
2736 assert(!SafepointSynchronize::is_at_safepoint() || used_and_free == capacity_bytes, "Accounting is wrong");
2737 }
2738
2739 // Print total fragmentation for class metaspaces
2740 void MetaspaceAux::print_class_waste(outputStream* out) {
2741 assert(Metaspace::using_class_space(), "class metaspace not used");
2742 size_t cls_specialized_waste = 0, cls_small_waste = 0, cls_medium_waste = 0;
2743 size_t cls_specialized_count = 0, cls_small_count = 0, cls_medium_count = 0, cls_humongous_count = 0;
2744 ClassLoaderDataGraphMetaspaceIterator iter;
2745 while (iter.repeat()) {
2746 Metaspace* msp = iter.get_next();
2747 if (msp != NULL) {
2748 cls_specialized_waste += msp->class_vsm()->sum_waste_in_chunks_in_use(SpecializedIndex);
2749 cls_specialized_count += msp->class_vsm()->sum_count_in_chunks_in_use(SpecializedIndex);
2750 cls_small_waste += msp->class_vsm()->sum_waste_in_chunks_in_use(SmallIndex);
2751 cls_small_count += msp->class_vsm()->sum_count_in_chunks_in_use(SmallIndex);
2752 cls_medium_waste += msp->class_vsm()->sum_waste_in_chunks_in_use(MediumIndex);
2753 cls_medium_count += msp->class_vsm()->sum_count_in_chunks_in_use(MediumIndex);
2754 cls_humongous_count += msp->class_vsm()->sum_count_in_chunks_in_use(HumongousIndex);
2755 }
2756 }
2757 out->print_cr(" class: " SIZE_FORMAT " specialized(s) " SIZE_FORMAT ", "
2758 SIZE_FORMAT " small(s) " SIZE_FORMAT ", "
2759 SIZE_FORMAT " medium(s) " SIZE_FORMAT ", "
2760 "large count " SIZE_FORMAT,
2761 cls_specialized_count, cls_specialized_waste,
2762 cls_small_count, cls_small_waste,
2763 cls_medium_count, cls_medium_waste, cls_humongous_count);
2764 }
2765
2766 // Print total fragmentation for data and class metaspaces separately
2767 void MetaspaceAux::print_waste(outputStream* out) {
2768 size_t specialized_waste = 0, small_waste = 0, medium_waste = 0;
2769 size_t specialized_count = 0, small_count = 0, medium_count = 0, humongous_count = 0;
2770
2771 ClassLoaderDataGraphMetaspaceIterator iter;
2772 while (iter.repeat()) {
2773 Metaspace* msp = iter.get_next();
2774 if (msp != NULL) {
2775 specialized_waste += msp->vsm()->sum_waste_in_chunks_in_use(SpecializedIndex);
2776 specialized_count += msp->vsm()->sum_count_in_chunks_in_use(SpecializedIndex);
2777 small_waste += msp->vsm()->sum_waste_in_chunks_in_use(SmallIndex);
2778 small_count += msp->vsm()->sum_count_in_chunks_in_use(SmallIndex);
2779 medium_waste += msp->vsm()->sum_waste_in_chunks_in_use(MediumIndex);
2780 medium_count += msp->vsm()->sum_count_in_chunks_in_use(MediumIndex);
2781 humongous_count += msp->vsm()->sum_count_in_chunks_in_use(HumongousIndex);
2782 }
2783 }
2784 out->print_cr("Total fragmentation waste (words) doesn't count free space");
2785 out->print_cr(" data: " SIZE_FORMAT " specialized(s) " SIZE_FORMAT ", "
2786 SIZE_FORMAT " small(s) " SIZE_FORMAT ", "
2787 SIZE_FORMAT " medium(s) " SIZE_FORMAT ", "
2788 "large count " SIZE_FORMAT,
2789 specialized_count, specialized_waste, small_count,
2790 small_waste, medium_count, medium_waste, humongous_count);
2791 if (Metaspace::using_class_space()) {
2792 print_class_waste(out);
2793 }
2794 }
2795
2796 // Dump global metaspace things from the end of ClassLoaderDataGraph
2797 void MetaspaceAux::dump(outputStream* out) {
2798 out->print_cr("All Metaspace:");
2799 out->print("data space: "); print_on(out, Metaspace::NonClassType);
2800 out->print("class space: "); print_on(out, Metaspace::ClassType);
2801 print_waste(out);
2802 }
2803
2804 void MetaspaceAux::verify_free_chunks() {
2805 Metaspace::space_list()->chunk_manager()->verify();
2806 if (Metaspace::using_class_space()) {
2807 Metaspace::class_space_list()->chunk_manager()->verify();
2808 }
2809 }
2810
2811 void MetaspaceAux::verify_capacity() {
2812 #ifdef ASSERT
2813 size_t running_sum_capacity_bytes = allocated_capacity_bytes();
2814 // For purposes of the running sum of capacity, verify against capacity
2815 size_t capacity_in_use_bytes = capacity_bytes_slow();
2816 assert(running_sum_capacity_bytes == capacity_in_use_bytes,
2817 err_msg("allocated_capacity_words() * BytesPerWord " SIZE_FORMAT
2818 " capacity_bytes_slow()" SIZE_FORMAT,
2819 running_sum_capacity_bytes, capacity_in_use_bytes));
2820 for (Metaspace::MetadataType i = Metaspace::ClassType;
2821 i < Metaspace:: MetadataTypeCount;
2822 i = (Metaspace::MetadataType)(i + 1)) {
2823 size_t capacity_in_use_bytes = capacity_bytes_slow(i);
2824 assert(allocated_capacity_bytes(i) == capacity_in_use_bytes,
2825 err_msg("allocated_capacity_bytes(%u) " SIZE_FORMAT
2826 " capacity_bytes_slow(%u)" SIZE_FORMAT,
2827 i, allocated_capacity_bytes(i), i, capacity_in_use_bytes));
2828 }
2829 #endif
2830 }
2831
2832 void MetaspaceAux::verify_used() {
2833 #ifdef ASSERT
2834 size_t running_sum_used_bytes = allocated_used_bytes();
2835 // For purposes of the running sum of used, verify against used
2836 size_t used_in_use_bytes = used_bytes_slow();
2837 assert(allocated_used_bytes() == used_in_use_bytes,
2838 err_msg("allocated_used_bytes() " SIZE_FORMAT
2839 " used_bytes_slow()" SIZE_FORMAT,
2840 allocated_used_bytes(), used_in_use_bytes));
2841 for (Metaspace::MetadataType i = Metaspace::ClassType;
2842 i < Metaspace:: MetadataTypeCount;
2843 i = (Metaspace::MetadataType)(i + 1)) {
2844 size_t used_in_use_bytes = used_bytes_slow(i);
2845 assert(allocated_used_bytes(i) == used_in_use_bytes,
2846 err_msg("allocated_used_bytes(%u) " SIZE_FORMAT
2847 " used_bytes_slow(%u)" SIZE_FORMAT,
2848 i, allocated_used_bytes(i), i, used_in_use_bytes));
2849 }
2850 #endif
2851 }
2852
2853 void MetaspaceAux::verify_metrics() {
2854 verify_capacity();
2855 verify_used();
2856 }
2857
2858
2859 // Metaspace methods
2860
2861 size_t Metaspace::_first_chunk_word_size = 0;
2862 size_t Metaspace::_first_class_chunk_word_size = 0;
2863
2864 Metaspace::Metaspace(Mutex* lock, MetaspaceType type) {
2865 initialize(lock, type);
2866 }
2867
2868 Metaspace::~Metaspace() {
2869 delete _vsm;
2870 if (using_class_space()) {
2871 delete _class_vsm;
2872 }
2873 }
2874
2875 VirtualSpaceList* Metaspace::_space_list = NULL;
2876 VirtualSpaceList* Metaspace::_class_space_list = NULL;
2877
2878 #define VIRTUALSPACEMULTIPLIER 2
2879
2880 #ifdef _LP64
2881 void Metaspace::set_narrow_klass_base_and_shift(address metaspace_base, address cds_base) {
2882 // Figure out the narrow_klass_base and the narrow_klass_shift. The
2883 // narrow_klass_base is the lower of the metaspace base and the cds base
2884 // (if cds is enabled). The narrow_klass_shift depends on the distance
2885 // between the lower base and higher address.
2886 address lower_base;
2887 address higher_address;
2888 if (UseSharedSpaces) {
2889 higher_address = MAX2((address)(cds_base + FileMapInfo::shared_spaces_size()),
2890 (address)(metaspace_base + class_metaspace_size()));
2891 lower_base = MIN2(metaspace_base, cds_base);
2892 } else {
2893 higher_address = metaspace_base + class_metaspace_size();
2894 lower_base = metaspace_base;
2895 }
2896 Universe::set_narrow_klass_base(lower_base);
2897 if ((uint64_t)(higher_address - lower_base) < (uint64_t)max_juint) {
2898 Universe::set_narrow_klass_shift(0);
2899 } else {
2900 assert(!UseSharedSpaces, "Cannot shift with UseSharedSpaces");
2901 Universe::set_narrow_klass_shift(LogKlassAlignmentInBytes);
2902 }
2903 }
2904
2905 // Return TRUE if the specified metaspace_base and cds_base are close enough
2906 // to work with compressed klass pointers.
2907 bool Metaspace::can_use_cds_with_metaspace_addr(char* metaspace_base, address cds_base) {
2908 assert(cds_base != 0 && UseSharedSpaces, "Only use with CDS");
2909 assert(UseCompressedClassPointers, "Only use with CompressedKlassPtrs");
2910 address lower_base = MIN2((address)metaspace_base, cds_base);
2911 address higher_address = MAX2((address)(cds_base + FileMapInfo::shared_spaces_size()),
2912 (address)(metaspace_base + class_metaspace_size()));
2913 return ((uint64_t)(higher_address - lower_base) < (uint64_t)max_juint);
2914 }
2915
2916 // Try to allocate the metaspace at the requested addr.
2917 void Metaspace::allocate_metaspace_compressed_klass_ptrs(char* requested_addr, address cds_base) {
2918 assert(using_class_space(), "called improperly");
2919 assert(UseCompressedClassPointers, "Only use with CompressedKlassPtrs");
2920 assert(class_metaspace_size() < KlassEncodingMetaspaceMax,
2921 "Metaspace size is too big");
2922
2923 ReservedSpace metaspace_rs = ReservedSpace(class_metaspace_size(),
2924 os::vm_allocation_granularity(),
2925 false, requested_addr, 0);
2926 if (!metaspace_rs.is_reserved()) {
2927 if (UseSharedSpaces) {
2928 // Keep trying to allocate the metaspace, increasing the requested_addr
2929 // by 1GB each time, until we reach an address that will no longer allow
2930 // use of CDS with compressed klass pointers.
2931 char *addr = requested_addr;
2932 while (!metaspace_rs.is_reserved() && (addr + 1*G > addr) &&
2933 can_use_cds_with_metaspace_addr(addr + 1*G, cds_base)) {
2934 addr = addr + 1*G;
2935 metaspace_rs = ReservedSpace(class_metaspace_size(),
2936 os::vm_allocation_granularity(), false, addr, 0);
2937 }
2938 }
2939
2940 // If no successful allocation then try to allocate the space anywhere. If
2941 // that fails then OOM doom. At this point we cannot try allocating the
2942 // metaspace as if UseCompressedClassPointers is off because too much
2943 // initialization has happened that depends on UseCompressedClassPointers.
2944 // So, UseCompressedClassPointers cannot be turned off at this point.
2945 if (!metaspace_rs.is_reserved()) {
2946 metaspace_rs = ReservedSpace(class_metaspace_size(),
2947 os::vm_allocation_granularity(), false);
2948 if (!metaspace_rs.is_reserved()) {
2949 vm_exit_during_initialization(err_msg("Could not allocate metaspace: %d bytes",
2950 class_metaspace_size()));
2951 }
2952 }
2953 }
2954
2955 // If we got here then the metaspace got allocated.
2956 MemTracker::record_virtual_memory_type((address)metaspace_rs.base(), mtClass);
2957
2958 // Verify that we can use shared spaces. Otherwise, turn off CDS.
2959 if (UseSharedSpaces && !can_use_cds_with_metaspace_addr(metaspace_rs.base(), cds_base)) {
2960 FileMapInfo::stop_sharing_and_unmap(
2961 "Could not allocate metaspace at a compatible address");
2962 }
2963
2964 set_narrow_klass_base_and_shift((address)metaspace_rs.base(),
2965 UseSharedSpaces ? (address)cds_base : 0);
2966
2967 initialize_class_space(metaspace_rs);
2968
2969 if (PrintCompressedOopsMode || (PrintMiscellaneous && Verbose)) {
2970 gclog_or_tty->print_cr("Narrow klass base: " PTR_FORMAT ", Narrow klass shift: " SIZE_FORMAT,
2971 Universe::narrow_klass_base(), Universe::narrow_klass_shift());
2972 gclog_or_tty->print_cr("Metaspace Size: " SIZE_FORMAT " Address: " PTR_FORMAT " Req Addr: " PTR_FORMAT,
2973 class_metaspace_size(), metaspace_rs.base(), requested_addr);
2974 }
2975 }
2976
2977 // For UseCompressedClassPointers the class space is reserved above the top of
2978 // the Java heap. The argument passed in is at the base of the compressed space.
2979 void Metaspace::initialize_class_space(ReservedSpace rs) {
2980 // The reserved space size may be bigger because of alignment, esp with UseLargePages
2981 assert(rs.size() >= CompressedClassSpaceSize,
2982 err_msg(SIZE_FORMAT " != " UINTX_FORMAT, rs.size(), CompressedClassSpaceSize));
2983 assert(using_class_space(), "Must be using class space");
2984 _class_space_list = new VirtualSpaceList(rs);
2985 }
2986
2987 #endif
2988
2989 void Metaspace::global_initialize() {
2990 // Initialize the alignment for shared spaces.
2991 int max_alignment = os::vm_page_size();
2992 size_t cds_total = 0;
2993
2994 set_class_metaspace_size(align_size_up(CompressedClassSpaceSize,
2995 os::vm_allocation_granularity()));
2996
2997 MetaspaceShared::set_max_alignment(max_alignment);
2998
2999 if (DumpSharedSpaces) {
3000 SharedReadOnlySize = align_size_up(SharedReadOnlySize, max_alignment);
3001 SharedReadWriteSize = align_size_up(SharedReadWriteSize, max_alignment);
3002 SharedMiscDataSize = align_size_up(SharedMiscDataSize, max_alignment);
3003 SharedMiscCodeSize = align_size_up(SharedMiscCodeSize, max_alignment);
3004
3005 // Initialize with the sum of the shared space sizes. The read-only
3006 // and read write metaspace chunks will be allocated out of this and the
3007 // remainder is the misc code and data chunks.
3008 cds_total = FileMapInfo::shared_spaces_size();
3009 _space_list = new VirtualSpaceList(cds_total/wordSize);
3010
3011 #ifdef _LP64
3012 // Set the compressed klass pointer base so that decoding of these pointers works
3013 // properly when creating the shared archive.
3014 assert(UseCompressedOops && UseCompressedClassPointers,
3015 "UseCompressedOops and UseCompressedClassPointers must be set");
3016 Universe::set_narrow_klass_base((address)_space_list->current_virtual_space()->bottom());
3017 if (TraceMetavirtualspaceAllocation && Verbose) {
3018 gclog_or_tty->print_cr("Setting_narrow_klass_base to Address: " PTR_FORMAT,
3019 _space_list->current_virtual_space()->bottom());
3020 }
3021
3022 // Set the shift to zero.
3023 assert(class_metaspace_size() < (uint64_t)(max_juint) - cds_total,
3024 "CDS region is too large");
3025 Universe::set_narrow_klass_shift(0);
3026 #endif
3027
3028 } else {
3029 // If using shared space, open the file that contains the shared space
3030 // and map in the memory before initializing the rest of metaspace (so
3031 // the addresses don't conflict)
3032 address cds_address = NULL;
3033 if (UseSharedSpaces) {
3034 FileMapInfo* mapinfo = new FileMapInfo();
3035 memset(mapinfo, 0, sizeof(FileMapInfo));
3036
3037 // Open the shared archive file, read and validate the header. If
3038 // initialization fails, shared spaces [UseSharedSpaces] are
3039 // disabled and the file is closed.
3040 // Map in spaces now also
3041 if (mapinfo->initialize() && MetaspaceShared::map_shared_spaces(mapinfo)) {
3042 FileMapInfo::set_current_info(mapinfo);
3043 } else {
3044 assert(!mapinfo->is_open() && !UseSharedSpaces,
3045 "archive file not closed or shared spaces not disabled.");
3046 }
3047 cds_total = FileMapInfo::shared_spaces_size();
3048 cds_address = (address)mapinfo->region_base(0);
3049 }
3050
3051 #ifdef _LP64
3052 // If UseCompressedClassPointers is set then allocate the metaspace area
3053 // above the heap and above the CDS area (if it exists).
3054 if (using_class_space()) {
3055 if (UseSharedSpaces) {
3056 allocate_metaspace_compressed_klass_ptrs((char *)(cds_address + cds_total), cds_address);
3057 } else {
3058 allocate_metaspace_compressed_klass_ptrs((char *)CompressedKlassPointersBase, 0);
3059 }
3060 }
3061 #endif
3062
3063 // Initialize these before initializing the VirtualSpaceList
3064 _first_chunk_word_size = InitialBootClassLoaderMetaspaceSize / BytesPerWord;
3065 _first_chunk_word_size = align_word_size_up(_first_chunk_word_size);
3066 // Make the first class chunk bigger than a medium chunk so it's not put
3067 // on the medium chunk list. The next chunk will be small and progress
3068 // from there. This size calculated by -version.
3069 _first_class_chunk_word_size = MIN2((size_t)MediumChunk*6,
3070 (CompressedClassSpaceSize/BytesPerWord)*2);
3071 _first_class_chunk_word_size = align_word_size_up(_first_class_chunk_word_size);
3072 // Arbitrarily set the initial virtual space to a multiple
3073 // of the boot class loader size.
3074 size_t word_size = VIRTUALSPACEMULTIPLIER * first_chunk_word_size();
3075 // Initialize the list of virtual spaces.
3076 _space_list = new VirtualSpaceList(word_size);
3077 }
3078 }
3079
3080 void Metaspace::initialize(Mutex* lock, MetaspaceType type) {
3081
3082 assert(space_list() != NULL,
3083 "Metadata VirtualSpaceList has not been initialized");
3084
3085 _vsm = new SpaceManager(NonClassType, lock, space_list());
3086 if (_vsm == NULL) {
3087 return;
3088 }
3089 size_t word_size;
3090 size_t class_word_size;
3091 vsm()->get_initial_chunk_sizes(type, &word_size, &class_word_size);
3092
3093 if (using_class_space()) {
3094 assert(class_space_list() != NULL,
3095 "Class VirtualSpaceList has not been initialized");
3096
3097 // Allocate SpaceManager for classes.
3098 _class_vsm = new SpaceManager(ClassType, lock, class_space_list());
3099 if (_class_vsm == NULL) {
3100 return;
3101 }
3102 }
3103
3104 MutexLockerEx cl(SpaceManager::expand_lock(), Mutex::_no_safepoint_check_flag);
3105
3106 // Allocate chunk for metadata objects
3107 Metachunk* new_chunk =
3108 space_list()->get_initialization_chunk(word_size,
3109 vsm()->medium_chunk_bunch());
3110 assert(!DumpSharedSpaces || new_chunk != NULL, "should have enough space for both chunks");
3111 if (new_chunk != NULL) {
3112 // Add to this manager's list of chunks in use and current_chunk().
3113 vsm()->add_chunk(new_chunk, true);
3114 }
3115
3116 // Allocate chunk for class metadata objects
3117 if (using_class_space()) {
3118 Metachunk* class_chunk =
3119 class_space_list()->get_initialization_chunk(class_word_size,
3120 class_vsm()->medium_chunk_bunch());
3121 if (class_chunk != NULL) {
3122 class_vsm()->add_chunk(class_chunk, true);
3123 }
3124 }
3125
3126 _alloc_record_head = NULL;
3127 _alloc_record_tail = NULL;
3128 }
3129
3130 size_t Metaspace::align_word_size_up(size_t word_size) {
3131 size_t byte_size = word_size * wordSize;
3132 return ReservedSpace::allocation_align_size_up(byte_size) / wordSize;
3133 }
3134
3135 MetaWord* Metaspace::allocate(size_t word_size, MetadataType mdtype) {
3136 // DumpSharedSpaces doesn't use class metadata area (yet)
3137 // Also, don't use class_vsm() unless UseCompressedClassPointers is true.
3138 if (mdtype == ClassType && using_class_space()) {
3139 return class_vsm()->allocate(word_size);
3140 } else {
3141 return vsm()->allocate(word_size);
3142 }
3143 }
3144
3145 MetaWord* Metaspace::expand_and_allocate(size_t word_size, MetadataType mdtype) {
3146 MetaWord* result;
3147 MetaspaceGC::set_expand_after_GC(true);
3148 size_t before_inc = MetaspaceGC::capacity_until_GC();
3149 size_t delta_bytes = MetaspaceGC::delta_capacity_until_GC(word_size) * BytesPerWord;
3150 MetaspaceGC::inc_capacity_until_GC(delta_bytes);
3151 if (PrintGCDetails && Verbose) {
3152 gclog_or_tty->print_cr("Increase capacity to GC from " SIZE_FORMAT
3153 " to " SIZE_FORMAT, before_inc, MetaspaceGC::capacity_until_GC());
3154 }
3155
3156 result = allocate(word_size, mdtype);
3157
3158 return result;
3159 }
3160
3161 // Space allocated in the Metaspace. This may
3162 // be across several metadata virtual spaces.
3163 char* Metaspace::bottom() const {
3164 assert(DumpSharedSpaces, "only useful and valid for dumping shared spaces");
3165 return (char*)vsm()->current_chunk()->bottom();
3166 }
3167
3168 size_t Metaspace::used_words_slow(MetadataType mdtype) const {
3169 if (mdtype == ClassType) {
3170 return using_class_space() ? class_vsm()->sum_used_in_chunks_in_use() : 0;
3171 } else {
3172 return vsm()->sum_used_in_chunks_in_use(); // includes overhead!
3173 }
3174 }
3175
3176 size_t Metaspace::free_words_slow(MetadataType mdtype) const {
3177 if (mdtype == ClassType) {
3178 return using_class_space() ? class_vsm()->sum_free_in_chunks_in_use() : 0;
3179 } else {
3180 return vsm()->sum_free_in_chunks_in_use();
3181 }
3182 }
3183
3184 // Space capacity in the Metaspace. It includes
3185 // space in the list of chunks from which allocations
3186 // have been made. Don't include space in the global freelist and
3187 // in the space available in the dictionary which
3188 // is already counted in some chunk.
3189 size_t Metaspace::capacity_words_slow(MetadataType mdtype) const {
3190 if (mdtype == ClassType) {
3191 return using_class_space() ? class_vsm()->sum_capacity_in_chunks_in_use() : 0;
3192 } else {
3193 return vsm()->sum_capacity_in_chunks_in_use();
3194 }
3195 }
3196
3197 size_t Metaspace::used_bytes_slow(MetadataType mdtype) const {
3198 return used_words_slow(mdtype) * BytesPerWord;
3199 }
3200
3201 size_t Metaspace::capacity_bytes_slow(MetadataType mdtype) const {
3202 return capacity_words_slow(mdtype) * BytesPerWord;
3203 }
3204
3205 void Metaspace::deallocate(MetaWord* ptr, size_t word_size, bool is_class) {
3206 if (SafepointSynchronize::is_at_safepoint()) {
3207 assert(Thread::current()->is_VM_thread(), "should be the VM thread");
3208 // Don't take Heap_lock
3209 MutexLockerEx ml(vsm()->lock(), Mutex::_no_safepoint_check_flag);
3210 if (word_size < TreeChunk<Metablock, FreeList>::min_size()) {
3211 // Dark matter. Too small for dictionary.
3212 #ifdef ASSERT
3213 Copy::fill_to_words((HeapWord*)ptr, word_size, 0xf5f5f5f5);
3214 #endif
3215 return;
3216 }
3217 if (is_class && using_class_space()) {
3218 class_vsm()->deallocate(ptr, word_size);
3219 } else {
3220 vsm()->deallocate(ptr, word_size);
3221 }
3222 } else {
3223 MutexLockerEx ml(vsm()->lock(), Mutex::_no_safepoint_check_flag);
3224
3225 if (word_size < TreeChunk<Metablock, FreeList>::min_size()) {
3226 // Dark matter. Too small for dictionary.
3227 #ifdef ASSERT
3228 Copy::fill_to_words((HeapWord*)ptr, word_size, 0xf5f5f5f5);
3229 #endif
3230 return;
3231 }
3232 if (is_class && using_class_space()) {
3233 class_vsm()->deallocate(ptr, word_size);
3234 } else {
3235 vsm()->deallocate(ptr, word_size);
3236 }
3237 }
3238 }
3239
3240 Metablock* Metaspace::allocate(ClassLoaderData* loader_data, size_t word_size,
3241 bool read_only, MetaspaceObj::Type type, TRAPS) {
3242 if (HAS_PENDING_EXCEPTION) {
3243 assert(false, "Should not allocate with exception pending");
3244 return NULL; // caller does a CHECK_NULL too
3245 }
3246
3247 MetadataType mdtype = (type == MetaspaceObj::ClassType) ? ClassType : NonClassType;
3248
3249 // SSS: Should we align the allocations and make sure the sizes are aligned.
3250 MetaWord* result = NULL;
3251
3252 assert(loader_data != NULL, "Should never pass around a NULL loader_data. "
3253 "ClassLoaderData::the_null_class_loader_data() should have been used.");
3254 // Allocate in metaspaces without taking out a lock, because it deadlocks
3255 // with the SymbolTable_lock. Dumping is single threaded for now. We'll have
3256 // to revisit this for application class data sharing.
3257 if (DumpSharedSpaces) {
3258 assert(type > MetaspaceObj::UnknownType && type < MetaspaceObj::_number_of_types, "sanity");
3259 Metaspace* space = read_only ? loader_data->ro_metaspace() : loader_data->rw_metaspace();
3260 result = space->allocate(word_size, NonClassType);
3261 if (result == NULL) {
3262 report_out_of_shared_space(read_only ? SharedReadOnly : SharedReadWrite);
3263 } else {
3264 space->record_allocation(result, type, space->vsm()->get_raw_word_size(word_size));
3265 }
3266 return Metablock::initialize(result, word_size);
3267 }
3268
3269 result = loader_data->metaspace_non_null()->allocate(word_size, mdtype);
3270
3271 if (result == NULL) {
3272 // Try to clean out some memory and retry.
3273 result =
3274 Universe::heap()->collector_policy()->satisfy_failed_metadata_allocation(
3275 loader_data, word_size, mdtype);
3276
3277 // If result is still null, we are out of memory.
3278 if (result == NULL) {
3279 if (Verbose && TraceMetadataChunkAllocation) {
3280 gclog_or_tty->print_cr("Metaspace allocation failed for size "
3281 SIZE_FORMAT, word_size);
3282 if (loader_data->metaspace_or_null() != NULL) loader_data->dump(gclog_or_tty);
3283 MetaspaceAux::dump(gclog_or_tty);
3284 }
3285 // -XX:+HeapDumpOnOutOfMemoryError and -XX:OnOutOfMemoryError support
3286 const char* space_string = (mdtype == ClassType) ? "Compressed class space" :
3287 "Metadata space";
3288 report_java_out_of_memory(space_string);
3289
3290 if (JvmtiExport::should_post_resource_exhausted()) {
3291 JvmtiExport::post_resource_exhausted(
3292 JVMTI_RESOURCE_EXHAUSTED_OOM_ERROR,
3293 space_string);
3294 }
3295 if (mdtype == ClassType) {
3296 THROW_OOP_0(Universe::out_of_memory_error_class_metaspace());
3297 } else {
3298 THROW_OOP_0(Universe::out_of_memory_error_metaspace());
3299 }
3300 }
3301 }
3302 return Metablock::initialize(result, word_size);
3303 }
3304
3305 void Metaspace::record_allocation(void* ptr, MetaspaceObj::Type type, size_t word_size) {
3306 assert(DumpSharedSpaces, "sanity");
3307
3308 AllocRecord *rec = new AllocRecord((address)ptr, type, (int)word_size * HeapWordSize);
3309 if (_alloc_record_head == NULL) {
3310 _alloc_record_head = _alloc_record_tail = rec;
3311 } else {
3312 _alloc_record_tail->_next = rec;
3313 _alloc_record_tail = rec;
3314 }
3315 }
3316
3317 void Metaspace::iterate(Metaspace::AllocRecordClosure *closure) {
3318 assert(DumpSharedSpaces, "unimplemented for !DumpSharedSpaces");
3319
3320 address last_addr = (address)bottom();
3321
3322 for (AllocRecord *rec = _alloc_record_head; rec; rec = rec->_next) {
3323 address ptr = rec->_ptr;
3324 if (last_addr < ptr) {
3325 closure->doit(last_addr, MetaspaceObj::UnknownType, ptr - last_addr);
3326 }
3327 closure->doit(ptr, rec->_type, rec->_byte_size);
3328 last_addr = ptr + rec->_byte_size;
3329 }
3330
3331 address top = ((address)bottom()) + used_bytes_slow(Metaspace::NonClassType);
3332 if (last_addr < top) {
3333 closure->doit(last_addr, MetaspaceObj::UnknownType, top - last_addr);
3334 }
3335 }
3336
3337 void Metaspace::purge() {
3338 MutexLockerEx cl(SpaceManager::expand_lock(),
3339 Mutex::_no_safepoint_check_flag);
3340 space_list()->purge();
3341 if (using_class_space()) {
3342 class_space_list()->purge();
3343 }
3344 }
3345
3346 void Metaspace::print_on(outputStream* out) const {
3347 // Print both class virtual space counts and metaspace.
3348 if (Verbose) {
3349 vsm()->print_on(out);
3350 if (using_class_space()) {
3351 class_vsm()->print_on(out);
3352 }
3353 }
3354 }
3355
3356 bool Metaspace::contains(const void * ptr) {
3357 if (MetaspaceShared::is_in_shared_space(ptr)) {
3358 return true;
3359 }
3360 // This is checked while unlocked. As long as the virtualspaces are added
3361 // at the end, the pointer will be in one of them. The virtual spaces
3362 // aren't deleted presently. When they are, some sort of locking might
3363 // be needed. Note, locking this can cause inversion problems with the
3364 // caller in MetaspaceObj::is_metadata() function.
3365 return space_list()->contains(ptr) ||
3366 (using_class_space() && class_space_list()->contains(ptr));
3367 }
3368
3369 void Metaspace::verify() {
3370 vsm()->verify();
3371 if (using_class_space()) {
3372 class_vsm()->verify();
3373 }
3374 }
3375
3376 void Metaspace::dump(outputStream* const out) const {
3377 out->print_cr("\nVirtual space manager: " INTPTR_FORMAT, vsm());
3378 vsm()->dump(out);
3379 if (using_class_space()) {
3380 out->print_cr("\nClass space manager: " INTPTR_FORMAT, class_vsm());
3381 class_vsm()->dump(out);
3382 }
3383 }
3384
3385 /////////////// Unit tests ///////////////
3386
3387 #ifndef PRODUCT
3388
3389 class MetaspaceAuxTest : AllStatic {
3390 public:
3391 static void test_reserved() {
3392 size_t reserved = MetaspaceAux::reserved_bytes();
3393
3394 assert(reserved > 0, "assert");
3395
3396 size_t committed = MetaspaceAux::committed_bytes();
3397 assert(committed <= reserved, "assert");
3398
3399 size_t reserved_metadata = MetaspaceAux::reserved_bytes(Metaspace::NonClassType);
3400 assert(reserved_metadata > 0, "assert");
3401 assert(reserved_metadata <= reserved, "assert");
3402
3403 if (UseCompressedClassPointers) {
3404 size_t reserved_class = MetaspaceAux::reserved_bytes(Metaspace::ClassType);
3405 assert(reserved_class > 0, "assert");
3406 assert(reserved_class < reserved, "assert");
3407 }
3408 }
3409
3410 static void test_committed() {
3411 size_t committed = MetaspaceAux::committed_bytes();
3412
3413 assert(committed > 0, "assert");
3414
3415 size_t reserved = MetaspaceAux::reserved_bytes();
3416 assert(committed <= reserved, "assert");
3417
3418 size_t committed_metadata = MetaspaceAux::committed_bytes(Metaspace::NonClassType);
3419 assert(committed_metadata > 0, "assert");
3420 assert(committed_metadata <= committed, "assert");
3421
3422 if (UseCompressedClassPointers) {
3423 size_t committed_class = MetaspaceAux::committed_bytes(Metaspace::ClassType);
3424 assert(committed_class > 0, "assert");
3425 assert(committed_class < committed, "assert");
3426 }
3427 }
3428
3429 static void test() {
3430 test_reserved();
3431 test_committed();
3432 }
3433 };
3434
3435 void MetaspaceAux_test() {
3436 MetaspaceAuxTest::test();
3437 }
3438
3439 #endif