Tue, 18 Dec 2012 10:40:51 +0100
8005108: NPG: MetaspaceAux::used_in_bytes(), capacity_in_bytes() and reserved_in_bytes() return inconsistent numbers
Summary: Reverted the changes to these functions from JDK-8000662
Reviewed-by: brutisso, jmasa
1 /*
2 * Copyright (c) 2011, 2012, 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.
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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.
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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.
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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/mutex.hpp"
39 #include "runtime/orderAccess.hpp"
40 #include "services/memTracker.hpp"
41 #include "utilities/copy.hpp"
42 #include "utilities/debug.hpp"
44 typedef BinaryTreeDictionary<Metablock, FreeList> BlockTreeDictionary;
45 typedef BinaryTreeDictionary<Metachunk, FreeList> ChunkTreeDictionary;
46 // Define this macro to enable slow integrity checking of
47 // the free chunk lists
48 const bool metaspace_slow_verify = false;
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 = 64 * K;
55 const size_t metadata_deallocate = 0xf5f5f5f5;
57 MetaWord* last_allocated = 0;
59 // Used in declarations in SpaceManager and ChunkManager
60 enum ChunkIndex {
61 SmallIndex = 0,
62 MediumIndex = 1,
63 HumongousIndex = 2,
64 NumberOfFreeLists = 2,
65 NumberOfInUseLists = 3
66 };
68 static ChunkIndex next_chunk_index(ChunkIndex i) {
69 assert(i < NumberOfInUseLists, "Out of bound");
70 return (ChunkIndex) (i+1);
71 }
73 // Originally _capacity_until_GC was set to MetaspaceSize here but
74 // the default MetaspaceSize before argument processing was being
75 // used which was not the desired value. See the code
76 // in should_expand() to see how the initialization is handled
77 // now.
78 size_t MetaspaceGC::_capacity_until_GC = 0;
79 bool MetaspaceGC::_expand_after_GC = false;
80 uint MetaspaceGC::_shrink_factor = 0;
81 bool MetaspaceGC::_should_concurrent_collect = false;
83 // Blocks of space for metadata are allocated out of Metachunks.
84 //
85 // Metachunk are allocated out of MetadataVirtualspaces and once
86 // allocated there is no explicit link between a Metachunk and
87 // the MetadataVirtualspaces from which it was allocated.
88 //
89 // Each SpaceManager maintains a
90 // list of the chunks it is using and the current chunk. The current
91 // chunk is the chunk from which allocations are done. Space freed in
92 // a chunk is placed on the free list of blocks (BlockFreelist) and
93 // reused from there.
95 // Pointer to list of Metachunks.
96 class ChunkList VALUE_OBJ_CLASS_SPEC {
97 // List of free chunks
98 Metachunk* _head;
100 public:
101 // Constructor
102 ChunkList() : _head(NULL) {}
104 // Accessors
105 Metachunk* head() { return _head; }
106 void set_head(Metachunk* v) { _head = v; }
108 // Link at head of the list
109 void add_at_head(Metachunk* head, Metachunk* tail);
110 void add_at_head(Metachunk* head);
112 size_t sum_list_size();
113 size_t sum_list_count();
114 size_t sum_list_capacity();
115 };
117 // Manages the global free lists of chunks.
118 // Has three lists of free chunks, and a total size and
119 // count that includes all three
121 class ChunkManager VALUE_OBJ_CLASS_SPEC {
123 // Free list of chunks of different sizes.
124 // SmallChunk
125 // MediumChunk
126 // HumongousChunk
127 ChunkList _free_chunks[NumberOfFreeLists];
129 // HumongousChunk
130 ChunkTreeDictionary _humongous_dictionary;
132 // ChunkManager in all lists of this type
133 size_t _free_chunks_total;
134 size_t _free_chunks_count;
136 void dec_free_chunks_total(size_t v) {
137 assert(_free_chunks_count > 0 &&
138 _free_chunks_total > 0,
139 "About to go negative");
140 Atomic::add_ptr(-1, &_free_chunks_count);
141 jlong minus_v = (jlong) - (jlong) v;
142 Atomic::add_ptr(minus_v, &_free_chunks_total);
143 }
145 // Debug support
147 size_t sum_free_chunks();
148 size_t sum_free_chunks_count();
150 void locked_verify_free_chunks_total();
151 void slow_locked_verify_free_chunks_total() {
152 if (metaspace_slow_verify) {
153 locked_verify_free_chunks_total();
154 }
155 }
156 void locked_verify_free_chunks_count();
157 void slow_locked_verify_free_chunks_count() {
158 if (metaspace_slow_verify) {
159 locked_verify_free_chunks_count();
160 }
161 }
162 void verify_free_chunks_count();
164 public:
166 ChunkManager() : _free_chunks_total(0), _free_chunks_count(0) {}
168 // add or delete (return) a chunk to the global freelist.
169 Metachunk* chunk_freelist_allocate(size_t word_size);
170 void chunk_freelist_deallocate(Metachunk* chunk);
172 // Total of the space in the free chunks list
173 size_t free_chunks_total();
174 size_t free_chunks_total_in_bytes();
176 // Number of chunks in the free chunks list
177 size_t free_chunks_count();
179 void inc_free_chunks_total(size_t v, size_t count = 1) {
180 Atomic::add_ptr(count, &_free_chunks_count);
181 Atomic::add_ptr(v, &_free_chunks_total);
182 }
183 ChunkList* free_medium_chunks() { return &_free_chunks[1]; }
184 ChunkList* free_small_chunks() { return &_free_chunks[0]; }
185 ChunkTreeDictionary* humongous_dictionary() {
186 return &_humongous_dictionary;
187 }
189 ChunkList* free_chunks(ChunkIndex index);
191 // Returns the list for the given chunk word size.
192 ChunkList* find_free_chunks_list(size_t word_size);
194 // Add and remove from a list by size. Selects
195 // list based on size of chunk.
196 void free_chunks_put(Metachunk* chuck);
197 Metachunk* free_chunks_get(size_t chunk_word_size);
199 // Debug support
200 void verify();
201 void slow_verify() {
202 if (metaspace_slow_verify) {
203 verify();
204 }
205 }
206 void locked_verify();
207 void slow_locked_verify() {
208 if (metaspace_slow_verify) {
209 locked_verify();
210 }
211 }
212 void verify_free_chunks_total();
214 void locked_print_free_chunks(outputStream* st);
215 void locked_print_sum_free_chunks(outputStream* st);
217 void print_on(outputStream* st);
218 };
221 // Used to manage the free list of Metablocks (a block corresponds
222 // to the allocation of a quantum of metadata).
223 class BlockFreelist VALUE_OBJ_CLASS_SPEC {
224 BlockTreeDictionary* _dictionary;
225 static Metablock* initialize_free_chunk(MetaWord* p, size_t word_size);
227 // Accessors
228 BlockTreeDictionary* dictionary() const { return _dictionary; }
230 public:
231 BlockFreelist();
232 ~BlockFreelist();
234 // Get and return a block to the free list
235 MetaWord* get_block(size_t word_size);
236 void return_block(MetaWord* p, size_t word_size);
238 size_t total_size() {
239 if (dictionary() == NULL) {
240 return 0;
241 } else {
242 return dictionary()->total_size();
243 }
244 }
246 void print_on(outputStream* st) const;
247 };
249 class VirtualSpaceNode : public CHeapObj<mtClass> {
250 friend class VirtualSpaceList;
252 // Link to next VirtualSpaceNode
253 VirtualSpaceNode* _next;
255 // total in the VirtualSpace
256 MemRegion _reserved;
257 ReservedSpace _rs;
258 VirtualSpace _virtual_space;
259 MetaWord* _top;
261 // Convenience functions for logical bottom and end
262 MetaWord* bottom() const { return (MetaWord*) _virtual_space.low(); }
263 MetaWord* end() const { return (MetaWord*) _virtual_space.high(); }
265 // Convenience functions to access the _virtual_space
266 char* low() const { return virtual_space()->low(); }
267 char* high() const { return virtual_space()->high(); }
269 public:
271 VirtualSpaceNode(size_t byte_size);
272 VirtualSpaceNode(ReservedSpace rs) : _top(NULL), _next(NULL), _rs(rs) {}
273 ~VirtualSpaceNode();
275 // address of next available space in _virtual_space;
276 // Accessors
277 VirtualSpaceNode* next() { return _next; }
278 void set_next(VirtualSpaceNode* v) { _next = v; }
280 void set_reserved(MemRegion const v) { _reserved = v; }
281 void set_top(MetaWord* v) { _top = v; }
283 // Accessors
284 MemRegion* reserved() { return &_reserved; }
285 VirtualSpace* virtual_space() const { return (VirtualSpace*) &_virtual_space; }
287 // Returns true if "word_size" is available in the virtual space
288 bool is_available(size_t word_size) { return _top + word_size <= end(); }
290 MetaWord* top() const { return _top; }
291 void inc_top(size_t word_size) { _top += word_size; }
293 // used and capacity in this single entry in the list
294 size_t used_words_in_vs() const;
295 size_t capacity_words_in_vs() const;
297 bool initialize();
299 // get space from the virtual space
300 Metachunk* take_from_committed(size_t chunk_word_size);
302 // Allocate a chunk from the virtual space and return it.
303 Metachunk* get_chunk_vs(size_t chunk_word_size);
304 Metachunk* get_chunk_vs_with_expand(size_t chunk_word_size);
306 // Expands/shrinks the committed space in a virtual space. Delegates
307 // to Virtualspace
308 bool expand_by(size_t words, bool pre_touch = false);
309 bool shrink_by(size_t words);
311 #ifdef ASSERT
312 // Debug support
313 static void verify_virtual_space_total();
314 static void verify_virtual_space_count();
315 void mangle();
316 #endif
318 void print_on(outputStream* st) const;
319 };
321 // byte_size is the size of the associated virtualspace.
322 VirtualSpaceNode::VirtualSpaceNode(size_t byte_size) : _top(NULL), _next(NULL), _rs(0) {
323 // This allocates memory with mmap. For DumpSharedspaces, allocate the
324 // space at low memory so that other shared images don't conflict.
325 // This is the same address as memory needed for UseCompressedOops but
326 // compressed oops don't work with CDS (offsets in metadata are wrong), so
327 // borrow the same address.
328 if (DumpSharedSpaces) {
329 char* shared_base = (char*)HeapBaseMinAddress;
330 _rs = ReservedSpace(byte_size, 0, false, shared_base, 0);
331 if (_rs.is_reserved()) {
332 assert(_rs.base() == shared_base, "should match");
333 } else {
334 // If we are dumping the heap, then allocate a wasted block of address
335 // space in order to push the heap to a lower address. This extra
336 // address range allows for other (or larger) libraries to be loaded
337 // without them occupying the space required for the shared spaces.
338 uintx reserved = 0;
339 uintx block_size = 64*1024*1024;
340 while (reserved < SharedDummyBlockSize) {
341 char* dummy = os::reserve_memory(block_size);
342 reserved += block_size;
343 }
344 _rs = ReservedSpace(byte_size);
345 }
346 MetaspaceShared::set_shared_rs(&_rs);
347 } else {
348 _rs = ReservedSpace(byte_size);
349 }
351 MemTracker::record_virtual_memory_type((address)_rs.base(), mtClass);
352 }
354 // List of VirtualSpaces for metadata allocation.
355 // It has a _next link for singly linked list and a MemRegion
356 // for total space in the VirtualSpace.
357 class VirtualSpaceList : public CHeapObj<mtClass> {
358 friend class VirtualSpaceNode;
360 enum VirtualSpaceSizes {
361 VirtualSpaceSize = 256 * K
362 };
364 // Global list of virtual spaces
365 // Head of the list
366 VirtualSpaceNode* _virtual_space_list;
367 // virtual space currently being used for allocations
368 VirtualSpaceNode* _current_virtual_space;
369 // Free chunk list for all other metadata
370 ChunkManager _chunk_manager;
372 // Can this virtual list allocate >1 spaces? Also, used to determine
373 // whether to allocate unlimited small chunks in this virtual space
374 bool _is_class;
375 bool can_grow() const { return !is_class() || !UseCompressedKlassPointers; }
377 // Sum of space in all virtual spaces and number of virtual spaces
378 size_t _virtual_space_total;
379 size_t _virtual_space_count;
381 ~VirtualSpaceList();
383 VirtualSpaceNode* virtual_space_list() const { return _virtual_space_list; }
385 void set_virtual_space_list(VirtualSpaceNode* v) {
386 _virtual_space_list = v;
387 }
388 void set_current_virtual_space(VirtualSpaceNode* v) {
389 _current_virtual_space = v;
390 }
392 void link_vs(VirtualSpaceNode* new_entry, size_t vs_word_size);
394 // Get another virtual space and add it to the list. This
395 // is typically prompted by a failed attempt to allocate a chunk
396 // and is typically followed by the allocation of a chunk.
397 bool grow_vs(size_t vs_word_size);
399 public:
400 VirtualSpaceList(size_t word_size);
401 VirtualSpaceList(ReservedSpace rs);
403 Metachunk* get_new_chunk(size_t word_size, size_t grow_chunks_by_words);
405 VirtualSpaceNode* current_virtual_space() {
406 return _current_virtual_space;
407 }
409 ChunkManager* chunk_manager() { return &_chunk_manager; }
410 bool is_class() const { return _is_class; }
412 // Allocate the first virtualspace.
413 void initialize(size_t word_size);
415 size_t virtual_space_total() { return _virtual_space_total; }
416 void inc_virtual_space_total(size_t v) {
417 Atomic::add_ptr(v, &_virtual_space_total);
418 }
420 size_t virtual_space_count() { return _virtual_space_count; }
421 void inc_virtual_space_count() {
422 Atomic::inc_ptr(&_virtual_space_count);
423 }
425 // Used and capacity in the entire list of virtual spaces.
426 // These are global values shared by all Metaspaces
427 size_t capacity_words_sum();
428 size_t capacity_bytes_sum() { return capacity_words_sum() * BytesPerWord; }
429 size_t used_words_sum();
430 size_t used_bytes_sum() { return used_words_sum() * BytesPerWord; }
432 bool contains(const void *ptr);
434 void print_on(outputStream* st) const;
436 class VirtualSpaceListIterator : public StackObj {
437 VirtualSpaceNode* _virtual_spaces;
438 public:
439 VirtualSpaceListIterator(VirtualSpaceNode* virtual_spaces) :
440 _virtual_spaces(virtual_spaces) {}
442 bool repeat() {
443 return _virtual_spaces != NULL;
444 }
446 VirtualSpaceNode* get_next() {
447 VirtualSpaceNode* result = _virtual_spaces;
448 if (_virtual_spaces != NULL) {
449 _virtual_spaces = _virtual_spaces->next();
450 }
451 return result;
452 }
453 };
454 };
456 class Metadebug : AllStatic {
457 // Debugging support for Metaspaces
458 static int _deallocate_block_a_lot_count;
459 static int _deallocate_chunk_a_lot_count;
460 static int _allocation_fail_alot_count;
462 public:
463 static int deallocate_block_a_lot_count() {
464 return _deallocate_block_a_lot_count;
465 }
466 static void set_deallocate_block_a_lot_count(int v) {
467 _deallocate_block_a_lot_count = v;
468 }
469 static void inc_deallocate_block_a_lot_count() {
470 _deallocate_block_a_lot_count++;
471 }
472 static int deallocate_chunk_a_lot_count() {
473 return _deallocate_chunk_a_lot_count;
474 }
475 static void reset_deallocate_chunk_a_lot_count() {
476 _deallocate_chunk_a_lot_count = 1;
477 }
478 static void inc_deallocate_chunk_a_lot_count() {
479 _deallocate_chunk_a_lot_count++;
480 }
482 static void init_allocation_fail_alot_count();
483 #ifdef ASSERT
484 static bool test_metadata_failure();
485 #endif
487 static void deallocate_chunk_a_lot(SpaceManager* sm,
488 size_t chunk_word_size);
489 static void deallocate_block_a_lot(SpaceManager* sm,
490 size_t chunk_word_size);
492 };
494 int Metadebug::_deallocate_block_a_lot_count = 0;
495 int Metadebug::_deallocate_chunk_a_lot_count = 0;
496 int Metadebug::_allocation_fail_alot_count = 0;
498 // SpaceManager - used by Metaspace to handle allocations
499 class SpaceManager : public CHeapObj<mtClass> {
500 friend class Metaspace;
501 friend class Metadebug;
503 private:
504 // protects allocations and contains.
505 Mutex* const _lock;
507 // List of chunks in use by this SpaceManager. Allocations
508 // are done from the current chunk. The list is used for deallocating
509 // chunks when the SpaceManager is freed.
510 Metachunk* _chunks_in_use[NumberOfInUseLists];
511 Metachunk* _current_chunk;
513 // Virtual space where allocation comes from.
514 VirtualSpaceList* _vs_list;
516 // Number of small chunks to allocate to a manager
517 // If class space manager, small chunks are unlimited
518 static uint const _small_chunk_limit;
519 bool has_small_chunk_limit() { return !vs_list()->is_class(); }
521 // Sum of all space in allocated chunks
522 size_t _allocation_total;
524 // Free lists of blocks are per SpaceManager since they
525 // are assumed to be in chunks in use by the SpaceManager
526 // and all chunks in use by a SpaceManager are freed when
527 // the class loader using the SpaceManager is collected.
528 BlockFreelist _block_freelists;
530 // protects virtualspace and chunk expansions
531 static const char* _expand_lock_name;
532 static const int _expand_lock_rank;
533 static Mutex* const _expand_lock;
535 // Accessors
536 Metachunk* chunks_in_use(ChunkIndex index) const { return _chunks_in_use[index]; }
537 void set_chunks_in_use(ChunkIndex index, Metachunk* v) { _chunks_in_use[index] = v; }
539 BlockFreelist* block_freelists() const {
540 return (BlockFreelist*) &_block_freelists;
541 }
543 VirtualSpaceList* vs_list() const { return _vs_list; }
545 Metachunk* current_chunk() const { return _current_chunk; }
546 void set_current_chunk(Metachunk* v) {
547 _current_chunk = v;
548 }
550 Metachunk* find_current_chunk(size_t word_size);
552 // Add chunk to the list of chunks in use
553 void add_chunk(Metachunk* v, bool make_current);
555 Mutex* lock() const { return _lock; }
557 public:
558 SpaceManager(Mutex* lock, VirtualSpaceList* vs_list);
559 ~SpaceManager();
561 enum ChunkSizes { // in words.
562 SmallChunk = 512,
563 MediumChunk = 8 * K,
564 MediumChunkBunch = 4 * MediumChunk
565 };
567 // Accessors
568 size_t allocation_total() const { return _allocation_total; }
569 void inc_allocation_total(size_t v) { Atomic::add_ptr(v, &_allocation_total); }
570 static bool is_humongous(size_t word_size) { return word_size > MediumChunk; }
572 static Mutex* expand_lock() { return _expand_lock; }
574 size_t sum_capacity_in_chunks_in_use() const;
575 size_t sum_used_in_chunks_in_use() const;
576 size_t sum_free_in_chunks_in_use() const;
577 size_t sum_waste_in_chunks_in_use() const;
578 size_t sum_waste_in_chunks_in_use(ChunkIndex index ) const;
580 size_t sum_count_in_chunks_in_use();
581 size_t sum_count_in_chunks_in_use(ChunkIndex i);
583 // Block allocation and deallocation.
584 // Allocates a block from the current chunk
585 MetaWord* allocate(size_t word_size);
587 // Helper for allocations
588 MetaWord* allocate_work(size_t word_size);
590 // Returns a block to the per manager freelist
591 void deallocate(MetaWord* p, size_t word_size);
593 // Based on the allocation size and a minimum chunk size,
594 // returned chunk size (for expanding space for chunk allocation).
595 size_t calc_chunk_size(size_t allocation_word_size);
597 // Called when an allocation from the current chunk fails.
598 // Gets a new chunk (may require getting a new virtual space),
599 // and allocates from that chunk.
600 MetaWord* grow_and_allocate(size_t word_size);
602 // debugging support.
604 void dump(outputStream* const out) const;
605 void print_on(outputStream* st) const;
606 void locked_print_chunks_in_use_on(outputStream* st) const;
608 void verify();
609 void verify_chunk_size(Metachunk* chunk);
610 NOT_PRODUCT(void mangle_freed_chunks();)
611 #ifdef ASSERT
612 void verify_allocation_total();
613 #endif
614 };
616 uint const SpaceManager::_small_chunk_limit = 4;
618 const char* SpaceManager::_expand_lock_name =
619 "SpaceManager chunk allocation lock";
620 const int SpaceManager::_expand_lock_rank = Monitor::leaf - 1;
621 Mutex* const SpaceManager::_expand_lock =
622 new Mutex(SpaceManager::_expand_lock_rank,
623 SpaceManager::_expand_lock_name,
624 Mutex::_allow_vm_block_flag);
626 // BlockFreelist methods
628 BlockFreelist::BlockFreelist() : _dictionary(NULL) {}
630 BlockFreelist::~BlockFreelist() {
631 if (_dictionary != NULL) {
632 if (Verbose && TraceMetadataChunkAllocation) {
633 _dictionary->print_free_lists(gclog_or_tty);
634 }
635 delete _dictionary;
636 }
637 }
639 Metablock* BlockFreelist::initialize_free_chunk(MetaWord* p, size_t word_size) {
640 Metablock* block = (Metablock*) p;
641 block->set_word_size(word_size);
642 block->set_prev(NULL);
643 block->set_next(NULL);
645 return block;
646 }
648 void BlockFreelist::return_block(MetaWord* p, size_t word_size) {
649 Metablock* free_chunk = initialize_free_chunk(p, word_size);
650 if (dictionary() == NULL) {
651 _dictionary = new BlockTreeDictionary();
652 }
653 dictionary()->return_chunk(free_chunk);
654 }
656 MetaWord* BlockFreelist::get_block(size_t word_size) {
657 if (dictionary() == NULL) {
658 return NULL;
659 }
661 if (word_size < TreeChunk<Metablock, FreeList>::min_size()) {
662 // Dark matter. Too small for dictionary.
663 return NULL;
664 }
666 Metablock* free_block =
667 dictionary()->get_chunk(word_size, FreeBlockDictionary<Metablock>::exactly);
668 if (free_block == NULL) {
669 return NULL;
670 }
672 return (MetaWord*) free_block;
673 }
675 void BlockFreelist::print_on(outputStream* st) const {
676 if (dictionary() == NULL) {
677 return;
678 }
679 dictionary()->print_free_lists(st);
680 }
682 // VirtualSpaceNode methods
684 VirtualSpaceNode::~VirtualSpaceNode() {
685 _rs.release();
686 }
688 size_t VirtualSpaceNode::used_words_in_vs() const {
689 return pointer_delta(top(), bottom(), sizeof(MetaWord));
690 }
692 // Space committed in the VirtualSpace
693 size_t VirtualSpaceNode::capacity_words_in_vs() const {
694 return pointer_delta(end(), bottom(), sizeof(MetaWord));
695 }
698 // Allocates the chunk from the virtual space only.
699 // This interface is also used internally for debugging. Not all
700 // chunks removed here are necessarily used for allocation.
701 Metachunk* VirtualSpaceNode::take_from_committed(size_t chunk_word_size) {
702 // Bottom of the new chunk
703 MetaWord* chunk_limit = top();
704 assert(chunk_limit != NULL, "Not safe to call this method");
706 if (!is_available(chunk_word_size)) {
707 if (TraceMetadataChunkAllocation) {
708 tty->print("VirtualSpaceNode::take_from_committed() not available %d words ", chunk_word_size);
709 // Dump some information about the virtual space that is nearly full
710 print_on(tty);
711 }
712 return NULL;
713 }
715 // Take the space (bump top on the current virtual space).
716 inc_top(chunk_word_size);
718 // Point the chunk at the space
719 Metachunk* result = Metachunk::initialize(chunk_limit, chunk_word_size);
720 return result;
721 }
724 // Expand the virtual space (commit more of the reserved space)
725 bool VirtualSpaceNode::expand_by(size_t words, bool pre_touch) {
726 size_t bytes = words * BytesPerWord;
727 bool result = virtual_space()->expand_by(bytes, pre_touch);
728 if (TraceMetavirtualspaceAllocation && !result) {
729 gclog_or_tty->print_cr("VirtualSpaceNode::expand_by() failed "
730 "for byte size " SIZE_FORMAT, bytes);
731 virtual_space()->print();
732 }
733 return result;
734 }
736 // Shrink the virtual space (commit more of the reserved space)
737 bool VirtualSpaceNode::shrink_by(size_t words) {
738 size_t bytes = words * BytesPerWord;
739 virtual_space()->shrink_by(bytes);
740 return true;
741 }
743 // Add another chunk to the chunk list.
745 Metachunk* VirtualSpaceNode::get_chunk_vs(size_t chunk_word_size) {
746 assert_lock_strong(SpaceManager::expand_lock());
747 Metachunk* result = NULL;
749 return take_from_committed(chunk_word_size);
750 }
752 Metachunk* VirtualSpaceNode::get_chunk_vs_with_expand(size_t chunk_word_size) {
753 assert_lock_strong(SpaceManager::expand_lock());
755 Metachunk* new_chunk = get_chunk_vs(chunk_word_size);
757 if (new_chunk == NULL) {
758 // Only a small part of the virtualspace is committed when first
759 // allocated so committing more here can be expected.
760 size_t page_size_words = os::vm_page_size() / BytesPerWord;
761 size_t aligned_expand_vs_by_words = align_size_up(chunk_word_size,
762 page_size_words);
763 expand_by(aligned_expand_vs_by_words, false);
764 new_chunk = get_chunk_vs(chunk_word_size);
765 }
766 return new_chunk;
767 }
769 bool VirtualSpaceNode::initialize() {
771 if (!_rs.is_reserved()) {
772 return false;
773 }
775 // Commit only 1 page instead of the whole reserved space _rs.size()
776 size_t committed_byte_size = os::vm_page_size();
777 bool result = virtual_space()->initialize(_rs, committed_byte_size);
778 if (result) {
779 set_top((MetaWord*)virtual_space()->low());
780 set_reserved(MemRegion((HeapWord*)_rs.base(),
781 (HeapWord*)(_rs.base() + _rs.size())));
783 assert(reserved()->start() == (HeapWord*) _rs.base(),
784 err_msg("Reserved start was not set properly " PTR_FORMAT
785 " != " PTR_FORMAT, reserved()->start(), _rs.base()));
786 assert(reserved()->word_size() == _rs.size() / BytesPerWord,
787 err_msg("Reserved size was not set properly " SIZE_FORMAT
788 " != " SIZE_FORMAT, reserved()->word_size(),
789 _rs.size() / BytesPerWord));
790 }
792 return result;
793 }
795 void VirtualSpaceNode::print_on(outputStream* st) const {
796 size_t used = used_words_in_vs();
797 size_t capacity = capacity_words_in_vs();
798 VirtualSpace* vs = virtual_space();
799 st->print_cr(" space @ " PTR_FORMAT " " SIZE_FORMAT "K, %3d%% used "
800 "[" PTR_FORMAT ", " PTR_FORMAT ", "
801 PTR_FORMAT ", " PTR_FORMAT ")",
802 vs, capacity / K, used * 100 / capacity,
803 bottom(), top(), end(),
804 vs->high_boundary());
805 }
807 #ifdef ASSERT
808 void VirtualSpaceNode::mangle() {
809 size_t word_size = capacity_words_in_vs();
810 Copy::fill_to_words((HeapWord*) low(), word_size, 0xf1f1f1f1);
811 }
812 #endif // ASSERT
814 // VirtualSpaceList methods
815 // Space allocated from the VirtualSpace
817 VirtualSpaceList::~VirtualSpaceList() {
818 VirtualSpaceListIterator iter(virtual_space_list());
819 while (iter.repeat()) {
820 VirtualSpaceNode* vsl = iter.get_next();
821 delete vsl;
822 }
823 }
825 size_t VirtualSpaceList::used_words_sum() {
826 size_t allocated_by_vs = 0;
827 VirtualSpaceListIterator iter(virtual_space_list());
828 while (iter.repeat()) {
829 VirtualSpaceNode* vsl = iter.get_next();
830 // Sum used region [bottom, top) in each virtualspace
831 allocated_by_vs += vsl->used_words_in_vs();
832 }
833 assert(allocated_by_vs >= chunk_manager()->free_chunks_total(),
834 err_msg("Total in free chunks " SIZE_FORMAT
835 " greater than total from virtual_spaces " SIZE_FORMAT,
836 allocated_by_vs, chunk_manager()->free_chunks_total()));
837 size_t used =
838 allocated_by_vs - chunk_manager()->free_chunks_total();
839 return used;
840 }
842 // Space available in all MetadataVirtualspaces allocated
843 // for metadata. This is the upper limit on the capacity
844 // of chunks allocated out of all the MetadataVirtualspaces.
845 size_t VirtualSpaceList::capacity_words_sum() {
846 size_t capacity = 0;
847 VirtualSpaceListIterator iter(virtual_space_list());
848 while (iter.repeat()) {
849 VirtualSpaceNode* vsl = iter.get_next();
850 capacity += vsl->capacity_words_in_vs();
851 }
852 return capacity;
853 }
855 VirtualSpaceList::VirtualSpaceList(size_t word_size ) :
856 _is_class(false),
857 _virtual_space_list(NULL),
858 _current_virtual_space(NULL),
859 _virtual_space_total(0),
860 _virtual_space_count(0) {
861 MutexLockerEx cl(SpaceManager::expand_lock(),
862 Mutex::_no_safepoint_check_flag);
863 bool initialization_succeeded = grow_vs(word_size);
865 assert(initialization_succeeded,
866 " VirtualSpaceList initialization should not fail");
867 }
869 VirtualSpaceList::VirtualSpaceList(ReservedSpace rs) :
870 _is_class(true),
871 _virtual_space_list(NULL),
872 _current_virtual_space(NULL),
873 _virtual_space_total(0),
874 _virtual_space_count(0) {
875 MutexLockerEx cl(SpaceManager::expand_lock(),
876 Mutex::_no_safepoint_check_flag);
877 VirtualSpaceNode* class_entry = new VirtualSpaceNode(rs);
878 bool succeeded = class_entry->initialize();
879 assert(succeeded, " VirtualSpaceList initialization should not fail");
880 link_vs(class_entry, rs.size()/BytesPerWord);
881 }
883 // Allocate another meta virtual space and add it to the list.
884 bool VirtualSpaceList::grow_vs(size_t vs_word_size) {
885 assert_lock_strong(SpaceManager::expand_lock());
886 if (vs_word_size == 0) {
887 return false;
888 }
889 // Reserve the space
890 size_t vs_byte_size = vs_word_size * BytesPerWord;
891 assert(vs_byte_size % os::vm_page_size() == 0, "Not aligned");
893 // Allocate the meta virtual space and initialize it.
894 VirtualSpaceNode* new_entry = new VirtualSpaceNode(vs_byte_size);
895 if (!new_entry->initialize()) {
896 delete new_entry;
897 return false;
898 } else {
899 // ensure lock-free iteration sees fully initialized node
900 OrderAccess::storestore();
901 link_vs(new_entry, vs_word_size);
902 return true;
903 }
904 }
906 void VirtualSpaceList::link_vs(VirtualSpaceNode* new_entry, size_t vs_word_size) {
907 if (virtual_space_list() == NULL) {
908 set_virtual_space_list(new_entry);
909 } else {
910 current_virtual_space()->set_next(new_entry);
911 }
912 set_current_virtual_space(new_entry);
913 inc_virtual_space_total(vs_word_size);
914 inc_virtual_space_count();
915 #ifdef ASSERT
916 new_entry->mangle();
917 #endif
918 if (TraceMetavirtualspaceAllocation && Verbose) {
919 VirtualSpaceNode* vsl = current_virtual_space();
920 vsl->print_on(tty);
921 }
922 }
924 Metachunk* VirtualSpaceList::get_new_chunk(size_t word_size,
925 size_t grow_chunks_by_words) {
927 // Get a chunk from the chunk freelist
928 Metachunk* next = chunk_manager()->chunk_freelist_allocate(grow_chunks_by_words);
930 // Allocate a chunk out of the current virtual space.
931 if (next == NULL) {
932 next = current_virtual_space()->get_chunk_vs(grow_chunks_by_words);
933 }
935 if (next == NULL) {
936 // Not enough room in current virtual space. Try to commit
937 // more space.
938 size_t expand_vs_by_words = MAX2((size_t)SpaceManager::MediumChunkBunch,
939 grow_chunks_by_words);
940 size_t page_size_words = os::vm_page_size() / BytesPerWord;
941 size_t aligned_expand_vs_by_words = align_size_up(expand_vs_by_words,
942 page_size_words);
943 bool vs_expanded =
944 current_virtual_space()->expand_by(aligned_expand_vs_by_words, false);
945 if (!vs_expanded) {
946 // Should the capacity of the metaspaces be expanded for
947 // this allocation? If it's the virtual space for classes and is
948 // being used for CompressedHeaders, don't allocate a new virtualspace.
949 if (can_grow() && MetaspaceGC::should_expand(this, word_size)) {
950 // Get another virtual space.
951 size_t grow_vs_words =
952 MAX2((size_t)VirtualSpaceSize, aligned_expand_vs_by_words);
953 if (grow_vs(grow_vs_words)) {
954 // Got it. It's on the list now. Get a chunk from it.
955 next = current_virtual_space()->get_chunk_vs_with_expand(grow_chunks_by_words);
956 }
957 if (TraceMetadataHumongousAllocation && SpaceManager::is_humongous(word_size)) {
958 gclog_or_tty->print_cr(" aligned_expand_vs_by_words " PTR_FORMAT,
959 aligned_expand_vs_by_words);
960 gclog_or_tty->print_cr(" grow_vs_words " PTR_FORMAT,
961 grow_vs_words);
962 }
963 } else {
964 // Allocation will fail and induce a GC
965 if (TraceMetadataChunkAllocation && Verbose) {
966 gclog_or_tty->print_cr("VirtualSpaceList::get_new_chunk():"
967 " Fail instead of expand the metaspace");
968 }
969 }
970 } else {
971 // The virtual space expanded, get a new chunk
972 next = current_virtual_space()->get_chunk_vs(grow_chunks_by_words);
973 assert(next != NULL, "Just expanded, should succeed");
974 }
975 }
977 return next;
978 }
980 void VirtualSpaceList::print_on(outputStream* st) const {
981 if (TraceMetadataChunkAllocation && Verbose) {
982 VirtualSpaceListIterator iter(virtual_space_list());
983 while (iter.repeat()) {
984 VirtualSpaceNode* node = iter.get_next();
985 node->print_on(st);
986 }
987 }
988 }
990 bool VirtualSpaceList::contains(const void *ptr) {
991 VirtualSpaceNode* list = virtual_space_list();
992 VirtualSpaceListIterator iter(list);
993 while (iter.repeat()) {
994 VirtualSpaceNode* node = iter.get_next();
995 if (node->reserved()->contains(ptr)) {
996 return true;
997 }
998 }
999 return false;
1000 }
1003 // MetaspaceGC methods
1005 // VM_CollectForMetadataAllocation is the vm operation used to GC.
1006 // Within the VM operation after the GC the attempt to allocate the metadata
1007 // should succeed. If the GC did not free enough space for the metaspace
1008 // allocation, the HWM is increased so that another virtualspace will be
1009 // allocated for the metadata. With perm gen the increase in the perm
1010 // gen had bounds, MinMetaspaceExpansion and MaxMetaspaceExpansion. The
1011 // metaspace policy uses those as the small and large steps for the HWM.
1012 //
1013 // After the GC the compute_new_size() for MetaspaceGC is called to
1014 // resize the capacity of the metaspaces. The current implementation
1015 // is based on the flags MinHeapFreeRatio and MaxHeapFreeRatio used
1016 // to resize the Java heap by some GC's. New flags can be implemented
1017 // if really needed. MinHeapFreeRatio is used to calculate how much
1018 // free space is desirable in the metaspace capacity to decide how much
1019 // to increase the HWM. MaxHeapFreeRatio is used to decide how much
1020 // free space is desirable in the metaspace capacity before decreasing
1021 // the HWM.
1023 // Calculate the amount to increase the high water mark (HWM).
1024 // Increase by a minimum amount (MinMetaspaceExpansion) so that
1025 // another expansion is not requested too soon. If that is not
1026 // enough to satisfy the allocation (i.e. big enough for a word_size
1027 // allocation), increase by MaxMetaspaceExpansion. If that is still
1028 // not enough, expand by the size of the allocation (word_size) plus
1029 // some.
1030 size_t MetaspaceGC::delta_capacity_until_GC(size_t word_size) {
1031 size_t before_inc = MetaspaceGC::capacity_until_GC();
1032 size_t min_delta_words = MinMetaspaceExpansion / BytesPerWord;
1033 size_t max_delta_words = MaxMetaspaceExpansion / BytesPerWord;
1034 size_t page_size_words = os::vm_page_size() / BytesPerWord;
1035 size_t size_delta_words = align_size_up(word_size, page_size_words);
1036 size_t delta_words = MAX2(size_delta_words, min_delta_words);
1037 if (delta_words > min_delta_words) {
1038 // Don't want to hit the high water mark on the next
1039 // allocation so make the delta greater than just enough
1040 // for this allocation.
1041 delta_words = MAX2(delta_words, max_delta_words);
1042 if (delta_words > max_delta_words) {
1043 // This allocation is large but the next ones are probably not
1044 // so increase by the minimum.
1045 delta_words = delta_words + min_delta_words;
1046 }
1047 }
1048 return delta_words;
1049 }
1051 bool MetaspaceGC::should_expand(VirtualSpaceList* vsl, size_t word_size) {
1053 // Class virtual space should always be expanded. Call GC for the other
1054 // metadata virtual space.
1055 if (vsl == Metaspace::class_space_list()) return true;
1057 // If the user wants a limit, impose one.
1058 size_t max_metaspace_size_words = MaxMetaspaceSize / BytesPerWord;
1059 size_t metaspace_size_words = MetaspaceSize / BytesPerWord;
1060 if (!FLAG_IS_DEFAULT(MaxMetaspaceSize) &&
1061 vsl->capacity_words_sum() >= max_metaspace_size_words) {
1062 return false;
1063 }
1065 // If this is part of an allocation after a GC, expand
1066 // unconditionally.
1067 if(MetaspaceGC::expand_after_GC()) {
1068 return true;
1069 }
1071 // If the capacity is below the minimum capacity, allow the
1072 // expansion. Also set the high-water-mark (capacity_until_GC)
1073 // to that minimum capacity so that a GC will not be induced
1074 // until that minimum capacity is exceeded.
1075 if (vsl->capacity_words_sum() < metaspace_size_words ||
1076 capacity_until_GC() == 0) {
1077 set_capacity_until_GC(metaspace_size_words);
1078 return true;
1079 } else {
1080 if (vsl->capacity_words_sum() < capacity_until_GC()) {
1081 return true;
1082 } else {
1083 if (TraceMetadataChunkAllocation && Verbose) {
1084 gclog_or_tty->print_cr(" allocation request size " SIZE_FORMAT
1085 " capacity_until_GC " SIZE_FORMAT
1086 " capacity_words_sum " SIZE_FORMAT
1087 " used_words_sum " SIZE_FORMAT
1088 " free chunks " SIZE_FORMAT
1089 " free chunks count %d",
1090 word_size,
1091 capacity_until_GC(),
1092 vsl->capacity_words_sum(),
1093 vsl->used_words_sum(),
1094 vsl->chunk_manager()->free_chunks_total(),
1095 vsl->chunk_manager()->free_chunks_count());
1096 }
1097 return false;
1098 }
1099 }
1100 }
1102 // Variables are in bytes
1104 void MetaspaceGC::compute_new_size() {
1105 assert(_shrink_factor <= 100, "invalid shrink factor");
1106 uint current_shrink_factor = _shrink_factor;
1107 _shrink_factor = 0;
1109 VirtualSpaceList *vsl = Metaspace::space_list();
1111 size_t capacity_after_gc = vsl->capacity_bytes_sum();
1112 // Check to see if these two can be calculated without walking the CLDG
1113 size_t used_after_gc = vsl->used_bytes_sum();
1114 size_t capacity_until_GC = vsl->capacity_bytes_sum();
1115 size_t free_after_gc = capacity_until_GC - used_after_gc;
1117 const double minimum_free_percentage = MinHeapFreeRatio / 100.0;
1118 const double maximum_used_percentage = 1.0 - minimum_free_percentage;
1120 const double min_tmp = used_after_gc / maximum_used_percentage;
1121 size_t minimum_desired_capacity =
1122 (size_t)MIN2(min_tmp, double(max_uintx));
1123 // Don't shrink less than the initial generation size
1124 minimum_desired_capacity = MAX2(minimum_desired_capacity,
1125 MetaspaceSize);
1127 if (PrintGCDetails && Verbose) {
1128 const double free_percentage = ((double)free_after_gc) / capacity_until_GC;
1129 gclog_or_tty->print_cr("\nMetaspaceGC::compute_new_size: ");
1130 gclog_or_tty->print_cr(" "
1131 " minimum_free_percentage: %6.2f"
1132 " maximum_used_percentage: %6.2f",
1133 minimum_free_percentage,
1134 maximum_used_percentage);
1135 double d_free_after_gc = free_after_gc / (double) K;
1136 gclog_or_tty->print_cr(" "
1137 " free_after_gc : %6.1fK"
1138 " used_after_gc : %6.1fK"
1139 " capacity_after_gc : %6.1fK"
1140 " metaspace HWM : %6.1fK",
1141 free_after_gc / (double) K,
1142 used_after_gc / (double) K,
1143 capacity_after_gc / (double) K,
1144 capacity_until_GC / (double) K);
1145 gclog_or_tty->print_cr(" "
1146 " free_percentage: %6.2f",
1147 free_percentage);
1148 }
1151 if (capacity_until_GC < minimum_desired_capacity) {
1152 // If we have less capacity below the metaspace HWM, then
1153 // increment the HWM.
1154 size_t expand_bytes = minimum_desired_capacity - capacity_until_GC;
1155 // Don't expand unless it's significant
1156 if (expand_bytes >= MinMetaspaceExpansion) {
1157 size_t expand_words = expand_bytes / BytesPerWord;
1158 MetaspaceGC::inc_capacity_until_GC(expand_words);
1159 }
1160 if (PrintGCDetails && Verbose) {
1161 size_t new_capacity_until_GC = MetaspaceGC::capacity_until_GC_in_bytes();
1162 gclog_or_tty->print_cr(" expanding:"
1163 " minimum_desired_capacity: %6.1fK"
1164 " expand_words: %6.1fK"
1165 " MinMetaspaceExpansion: %6.1fK"
1166 " new metaspace HWM: %6.1fK",
1167 minimum_desired_capacity / (double) K,
1168 expand_bytes / (double) K,
1169 MinMetaspaceExpansion / (double) K,
1170 new_capacity_until_GC / (double) K);
1171 }
1172 return;
1173 }
1175 // No expansion, now see if we want to shrink
1176 size_t shrink_words = 0;
1177 // We would never want to shrink more than this
1178 size_t max_shrink_words = capacity_until_GC - minimum_desired_capacity;
1179 assert(max_shrink_words >= 0, err_msg("max_shrink_words " SIZE_FORMAT,
1180 max_shrink_words));
1182 // Should shrinking be considered?
1183 if (MaxHeapFreeRatio < 100) {
1184 const double maximum_free_percentage = MaxHeapFreeRatio / 100.0;
1185 const double minimum_used_percentage = 1.0 - maximum_free_percentage;
1186 const double max_tmp = used_after_gc / minimum_used_percentage;
1187 size_t maximum_desired_capacity = (size_t)MIN2(max_tmp, double(max_uintx));
1188 maximum_desired_capacity = MAX2(maximum_desired_capacity,
1189 MetaspaceSize);
1190 if (PrintGC && Verbose) {
1191 gclog_or_tty->print_cr(" "
1192 " maximum_free_percentage: %6.2f"
1193 " minimum_used_percentage: %6.2f",
1194 maximum_free_percentage,
1195 minimum_used_percentage);
1196 gclog_or_tty->print_cr(" "
1197 " capacity_until_GC: %6.1fK"
1198 " minimum_desired_capacity: %6.1fK"
1199 " maximum_desired_capacity: %6.1fK",
1200 capacity_until_GC / (double) K,
1201 minimum_desired_capacity / (double) K,
1202 maximum_desired_capacity / (double) K);
1203 }
1205 assert(minimum_desired_capacity <= maximum_desired_capacity,
1206 "sanity check");
1208 if (capacity_until_GC > maximum_desired_capacity) {
1209 // Capacity too large, compute shrinking size
1210 shrink_words = capacity_until_GC - maximum_desired_capacity;
1211 // We don't want shrink all the way back to initSize if people call
1212 // System.gc(), because some programs do that between "phases" and then
1213 // we'd just have to grow the heap up again for the next phase. So we
1214 // damp the shrinking: 0% on the first call, 10% on the second call, 40%
1215 // on the third call, and 100% by the fourth call. But if we recompute
1216 // size without shrinking, it goes back to 0%.
1217 shrink_words = shrink_words / 100 * current_shrink_factor;
1218 assert(shrink_words <= max_shrink_words,
1219 err_msg("invalid shrink size " SIZE_FORMAT " not <= " SIZE_FORMAT,
1220 shrink_words, max_shrink_words));
1221 if (current_shrink_factor == 0) {
1222 _shrink_factor = 10;
1223 } else {
1224 _shrink_factor = MIN2(current_shrink_factor * 4, (uint) 100);
1225 }
1226 if (PrintGCDetails && Verbose) {
1227 gclog_or_tty->print_cr(" "
1228 " shrinking:"
1229 " initSize: %.1fK"
1230 " maximum_desired_capacity: %.1fK",
1231 MetaspaceSize / (double) K,
1232 maximum_desired_capacity / (double) K);
1233 gclog_or_tty->print_cr(" "
1234 " shrink_words: %.1fK"
1235 " current_shrink_factor: %d"
1236 " new shrink factor: %d"
1237 " MinMetaspaceExpansion: %.1fK",
1238 shrink_words / (double) K,
1239 current_shrink_factor,
1240 _shrink_factor,
1241 MinMetaspaceExpansion / (double) K);
1242 }
1243 }
1244 }
1247 // Don't shrink unless it's significant
1248 if (shrink_words >= MinMetaspaceExpansion) {
1249 VirtualSpaceNode* csp = vsl->current_virtual_space();
1250 size_t available_to_shrink = csp->capacity_words_in_vs() -
1251 csp->used_words_in_vs();
1252 shrink_words = MIN2(shrink_words, available_to_shrink);
1253 csp->shrink_by(shrink_words);
1254 MetaspaceGC::dec_capacity_until_GC(shrink_words);
1255 if (PrintGCDetails && Verbose) {
1256 size_t new_capacity_until_GC = MetaspaceGC::capacity_until_GC_in_bytes();
1257 gclog_or_tty->print_cr(" metaspace HWM: %.1fK", new_capacity_until_GC / (double) K);
1258 }
1259 }
1260 assert(vsl->used_bytes_sum() == used_after_gc &&
1261 used_after_gc <= vsl->capacity_bytes_sum(),
1262 "sanity check");
1264 }
1266 // Metadebug methods
1268 void Metadebug::deallocate_chunk_a_lot(SpaceManager* sm,
1269 size_t chunk_word_size){
1270 #ifdef ASSERT
1271 VirtualSpaceList* vsl = sm->vs_list();
1272 if (MetaDataDeallocateALot &&
1273 Metadebug::deallocate_chunk_a_lot_count() % MetaDataDeallocateALotInterval == 0 ) {
1274 Metadebug::reset_deallocate_chunk_a_lot_count();
1275 for (uint i = 0; i < metadata_deallocate_a_lock_chunk; i++) {
1276 Metachunk* dummy_chunk = vsl->current_virtual_space()->take_from_committed(chunk_word_size);
1277 if (dummy_chunk == NULL) {
1278 break;
1279 }
1280 vsl->chunk_manager()->chunk_freelist_deallocate(dummy_chunk);
1282 if (TraceMetadataChunkAllocation && Verbose) {
1283 gclog_or_tty->print("Metadebug::deallocate_chunk_a_lot: %d) ",
1284 sm->sum_count_in_chunks_in_use());
1285 dummy_chunk->print_on(gclog_or_tty);
1286 gclog_or_tty->print_cr(" Free chunks total %d count %d",
1287 vsl->chunk_manager()->free_chunks_total(),
1288 vsl->chunk_manager()->free_chunks_count());
1289 }
1290 }
1291 } else {
1292 Metadebug::inc_deallocate_chunk_a_lot_count();
1293 }
1294 #endif
1295 }
1297 void Metadebug::deallocate_block_a_lot(SpaceManager* sm,
1298 size_t raw_word_size){
1299 #ifdef ASSERT
1300 if (MetaDataDeallocateALot &&
1301 Metadebug::deallocate_block_a_lot_count() % MetaDataDeallocateALotInterval == 0 ) {
1302 Metadebug::set_deallocate_block_a_lot_count(0);
1303 for (uint i = 0; i < metadata_deallocate_a_lot_block; i++) {
1304 MetaWord* dummy_block = sm->allocate_work(raw_word_size);
1305 if (dummy_block == 0) {
1306 break;
1307 }
1308 sm->deallocate(dummy_block, raw_word_size);
1309 }
1310 } else {
1311 Metadebug::inc_deallocate_block_a_lot_count();
1312 }
1313 #endif
1314 }
1316 void Metadebug::init_allocation_fail_alot_count() {
1317 if (MetadataAllocationFailALot) {
1318 _allocation_fail_alot_count =
1319 1+(long)((double)MetadataAllocationFailALotInterval*os::random()/(max_jint+1.0));
1320 }
1321 }
1323 #ifdef ASSERT
1324 bool Metadebug::test_metadata_failure() {
1325 if (MetadataAllocationFailALot &&
1326 Threads::is_vm_complete()) {
1327 if (_allocation_fail_alot_count > 0) {
1328 _allocation_fail_alot_count--;
1329 } else {
1330 if (TraceMetadataChunkAllocation && Verbose) {
1331 gclog_or_tty->print_cr("Metadata allocation failing for "
1332 "MetadataAllocationFailALot");
1333 }
1334 init_allocation_fail_alot_count();
1335 return true;
1336 }
1337 }
1338 return false;
1339 }
1340 #endif
1342 // ChunkList methods
1344 size_t ChunkList::sum_list_size() {
1345 size_t result = 0;
1346 Metachunk* cur = head();
1347 while (cur != NULL) {
1348 result += cur->word_size();
1349 cur = cur->next();
1350 }
1351 return result;
1352 }
1354 size_t ChunkList::sum_list_count() {
1355 size_t result = 0;
1356 Metachunk* cur = head();
1357 while (cur != NULL) {
1358 result++;
1359 cur = cur->next();
1360 }
1361 return result;
1362 }
1364 size_t ChunkList::sum_list_capacity() {
1365 size_t result = 0;
1366 Metachunk* cur = head();
1367 while (cur != NULL) {
1368 result += cur->capacity_word_size();
1369 cur = cur->next();
1370 }
1371 return result;
1372 }
1374 void ChunkList::add_at_head(Metachunk* head, Metachunk* tail) {
1375 assert_lock_strong(SpaceManager::expand_lock());
1376 assert(tail->next() == NULL, "Not the tail");
1378 if (TraceMetadataChunkAllocation && Verbose) {
1379 tty->print("ChunkList::add_at_head: ");
1380 Metachunk* cur = head;
1381 while (cur != NULL) {
1382 tty->print(PTR_FORMAT " (" SIZE_FORMAT ") ", cur, cur->word_size());
1383 cur = cur->next();
1384 }
1385 tty->print_cr("");
1386 }
1388 if (tail != NULL) {
1389 tail->set_next(_head);
1390 }
1391 set_head(head);
1392 }
1394 void ChunkList::add_at_head(Metachunk* list) {
1395 if (list == NULL) {
1396 // Nothing to add
1397 return;
1398 }
1399 assert_lock_strong(SpaceManager::expand_lock());
1400 Metachunk* head = list;
1401 Metachunk* tail = list;
1402 Metachunk* cur = head->next();
1403 // Search for the tail since it is not passed.
1404 while (cur != NULL) {
1405 tail = cur;
1406 cur = cur->next();
1407 }
1408 add_at_head(head, tail);
1409 }
1411 // ChunkManager methods
1413 // Verification of _free_chunks_total and _free_chunks_count does not
1414 // work with the CMS collector because its use of additional locks
1415 // complicate the mutex deadlock detection but it can still be useful
1416 // for detecting errors in the chunk accounting with other collectors.
1418 size_t ChunkManager::free_chunks_total() {
1419 #ifdef ASSERT
1420 if (!UseConcMarkSweepGC && !SpaceManager::expand_lock()->is_locked()) {
1421 MutexLockerEx cl(SpaceManager::expand_lock(),
1422 Mutex::_no_safepoint_check_flag);
1423 slow_locked_verify_free_chunks_total();
1424 }
1425 #endif
1426 return _free_chunks_total;
1427 }
1429 size_t ChunkManager::free_chunks_total_in_bytes() {
1430 return free_chunks_total() * BytesPerWord;
1431 }
1433 size_t ChunkManager::free_chunks_count() {
1434 #ifdef ASSERT
1435 if (!UseConcMarkSweepGC && !SpaceManager::expand_lock()->is_locked()) {
1436 MutexLockerEx cl(SpaceManager::expand_lock(),
1437 Mutex::_no_safepoint_check_flag);
1438 // This lock is only needed in debug because the verification
1439 // of the _free_chunks_totals walks the list of free chunks
1440 slow_locked_verify_free_chunks_count();
1441 }
1442 #endif
1443 return _free_chunks_count;
1444 }
1446 void ChunkManager::locked_verify_free_chunks_total() {
1447 assert_lock_strong(SpaceManager::expand_lock());
1448 assert(sum_free_chunks() == _free_chunks_total,
1449 err_msg("_free_chunks_total " SIZE_FORMAT " is not the"
1450 " same as sum " SIZE_FORMAT, _free_chunks_total,
1451 sum_free_chunks()));
1452 }
1454 void ChunkManager::verify_free_chunks_total() {
1455 MutexLockerEx cl(SpaceManager::expand_lock(),
1456 Mutex::_no_safepoint_check_flag);
1457 locked_verify_free_chunks_total();
1458 }
1460 void ChunkManager::locked_verify_free_chunks_count() {
1461 assert_lock_strong(SpaceManager::expand_lock());
1462 assert(sum_free_chunks_count() == _free_chunks_count,
1463 err_msg("_free_chunks_count " SIZE_FORMAT " is not the"
1464 " same as sum " SIZE_FORMAT, _free_chunks_count,
1465 sum_free_chunks_count()));
1466 }
1468 void ChunkManager::verify_free_chunks_count() {
1469 #ifdef ASSERT
1470 MutexLockerEx cl(SpaceManager::expand_lock(),
1471 Mutex::_no_safepoint_check_flag);
1472 locked_verify_free_chunks_count();
1473 #endif
1474 }
1476 void ChunkManager::verify() {
1477 MutexLockerEx cl(SpaceManager::expand_lock(),
1478 Mutex::_no_safepoint_check_flag);
1479 locked_verify();
1480 }
1482 void ChunkManager::locked_verify() {
1483 locked_verify_free_chunks_count();
1484 locked_verify_free_chunks_total();
1485 }
1487 void ChunkManager::locked_print_free_chunks(outputStream* st) {
1488 assert_lock_strong(SpaceManager::expand_lock());
1489 st->print_cr("Free chunk total 0x%x count 0x%x",
1490 _free_chunks_total, _free_chunks_count);
1491 }
1493 void ChunkManager::locked_print_sum_free_chunks(outputStream* st) {
1494 assert_lock_strong(SpaceManager::expand_lock());
1495 st->print_cr("Sum free chunk total 0x%x count 0x%x",
1496 sum_free_chunks(), sum_free_chunks_count());
1497 }
1498 ChunkList* ChunkManager::free_chunks(ChunkIndex index) {
1499 return &_free_chunks[index];
1500 }
1502 // These methods that sum the free chunk lists are used in printing
1503 // methods that are used in product builds.
1504 size_t ChunkManager::sum_free_chunks() {
1505 assert_lock_strong(SpaceManager::expand_lock());
1506 size_t result = 0;
1507 for (ChunkIndex i = SmallIndex; i < NumberOfFreeLists; i = next_chunk_index(i)) {
1508 ChunkList* list = free_chunks(i);
1510 if (list == NULL) {
1511 continue;
1512 }
1514 result = result + list->sum_list_capacity();
1515 }
1516 result = result + humongous_dictionary()->total_size();
1517 return result;
1518 }
1520 size_t ChunkManager::sum_free_chunks_count() {
1521 assert_lock_strong(SpaceManager::expand_lock());
1522 size_t count = 0;
1523 for (ChunkIndex i = SmallIndex; i < NumberOfFreeLists; i = next_chunk_index(i)) {
1524 ChunkList* list = free_chunks(i);
1525 if (list == NULL) {
1526 continue;
1527 }
1528 count = count + list->sum_list_count();
1529 }
1530 count = count + humongous_dictionary()->total_free_blocks();
1531 return count;
1532 }
1534 ChunkList* ChunkManager::find_free_chunks_list(size_t word_size) {
1535 switch (word_size) {
1536 case SpaceManager::SmallChunk :
1537 return &_free_chunks[0];
1538 case SpaceManager::MediumChunk :
1539 return &_free_chunks[1];
1540 default:
1541 assert(word_size > SpaceManager::MediumChunk, "List inconsistency");
1542 return &_free_chunks[2];
1543 }
1544 }
1546 void ChunkManager::free_chunks_put(Metachunk* chunk) {
1547 assert_lock_strong(SpaceManager::expand_lock());
1548 ChunkList* free_list = find_free_chunks_list(chunk->word_size());
1549 chunk->set_next(free_list->head());
1550 free_list->set_head(chunk);
1551 // chunk is being returned to the chunk free list
1552 inc_free_chunks_total(chunk->capacity_word_size());
1553 slow_locked_verify();
1554 }
1556 void ChunkManager::chunk_freelist_deallocate(Metachunk* chunk) {
1557 // The deallocation of a chunk originates in the freelist
1558 // manangement code for a Metaspace and does not hold the
1559 // lock.
1560 assert(chunk != NULL, "Deallocating NULL");
1561 assert_lock_strong(SpaceManager::expand_lock());
1562 slow_locked_verify();
1563 if (TraceMetadataChunkAllocation) {
1564 tty->print_cr("ChunkManager::chunk_freelist_deallocate: chunk "
1565 PTR_FORMAT " size " SIZE_FORMAT,
1566 chunk, chunk->word_size());
1567 }
1568 free_chunks_put(chunk);
1569 }
1571 Metachunk* ChunkManager::free_chunks_get(size_t word_size) {
1572 assert_lock_strong(SpaceManager::expand_lock());
1574 slow_locked_verify();
1576 Metachunk* chunk = NULL;
1577 if (!SpaceManager::is_humongous(word_size)) {
1578 ChunkList* free_list = find_free_chunks_list(word_size);
1579 assert(free_list != NULL, "Sanity check");
1581 chunk = free_list->head();
1582 debug_only(Metachunk* debug_head = chunk;)
1584 if (chunk == NULL) {
1585 return NULL;
1586 }
1588 // Remove the chunk as the head of the list.
1589 free_list->set_head(chunk->next());
1590 chunk->set_next(NULL);
1591 // Chunk has been removed from the chunks free list.
1592 dec_free_chunks_total(chunk->capacity_word_size());
1594 if (TraceMetadataChunkAllocation && Verbose) {
1595 tty->print_cr("ChunkManager::free_chunks_get: free_list "
1596 PTR_FORMAT " head " PTR_FORMAT " size " SIZE_FORMAT,
1597 free_list, chunk, chunk->word_size());
1598 }
1599 } else {
1600 chunk = humongous_dictionary()->get_chunk(
1601 word_size,
1602 FreeBlockDictionary<Metachunk>::atLeast);
1604 if (chunk != NULL) {
1605 if (TraceMetadataHumongousAllocation) {
1606 size_t waste = chunk->word_size() - word_size;
1607 tty->print_cr("Free list allocate humongous chunk size " SIZE_FORMAT
1608 " for requested size " SIZE_FORMAT
1609 " waste " SIZE_FORMAT,
1610 chunk->word_size(), word_size, waste);
1611 }
1612 // Chunk is being removed from the chunks free list.
1613 dec_free_chunks_total(chunk->capacity_word_size());
1614 #ifdef ASSERT
1615 chunk->set_is_free(false);
1616 #endif
1617 }
1618 }
1619 slow_locked_verify();
1620 return chunk;
1621 }
1623 Metachunk* ChunkManager::chunk_freelist_allocate(size_t word_size) {
1624 assert_lock_strong(SpaceManager::expand_lock());
1625 slow_locked_verify();
1627 // Take from the beginning of the list
1628 Metachunk* chunk = free_chunks_get(word_size);
1629 if (chunk == NULL) {
1630 return NULL;
1631 }
1633 assert(word_size <= chunk->word_size() ||
1634 SpaceManager::is_humongous(chunk->word_size()),
1635 "Non-humongous variable sized chunk");
1636 if (TraceMetadataChunkAllocation) {
1637 tty->print("ChunkManager::chunk_freelist_allocate: chunk "
1638 PTR_FORMAT " size " SIZE_FORMAT " ",
1639 chunk, chunk->word_size());
1640 locked_print_free_chunks(tty);
1641 }
1643 return chunk;
1644 }
1646 void ChunkManager::print_on(outputStream* out) {
1647 if (PrintFLSStatistics != 0) {
1648 humongous_dictionary()->report_statistics();
1649 }
1650 }
1652 // SpaceManager methods
1654 size_t SpaceManager::sum_free_in_chunks_in_use() const {
1655 MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag);
1656 size_t free = 0;
1657 for (ChunkIndex i = SmallIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) {
1658 Metachunk* chunk = chunks_in_use(i);
1659 while (chunk != NULL) {
1660 free += chunk->free_word_size();
1661 chunk = chunk->next();
1662 }
1663 }
1664 return free;
1665 }
1667 size_t SpaceManager::sum_waste_in_chunks_in_use() const {
1668 MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag);
1669 size_t result = 0;
1670 for (ChunkIndex i = SmallIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) {
1673 result += sum_waste_in_chunks_in_use(i);
1674 }
1676 return result;
1677 }
1679 size_t SpaceManager::sum_waste_in_chunks_in_use(ChunkIndex index) const {
1680 size_t result = 0;
1681 size_t count = 0;
1682 Metachunk* chunk = chunks_in_use(index);
1683 // Count the free space in all the chunk but not the
1684 // current chunk from which allocations are still being done.
1685 if (chunk != NULL) {
1686 Metachunk* prev = chunk;
1687 while (chunk != NULL && chunk != current_chunk()) {
1688 result += chunk->free_word_size();
1689 prev = chunk;
1690 chunk = chunk->next();
1691 count++;
1692 }
1693 }
1694 return result;
1695 }
1697 size_t SpaceManager::sum_capacity_in_chunks_in_use() const {
1698 MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag);
1699 size_t sum = 0;
1700 for (ChunkIndex i = SmallIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) {
1701 Metachunk* chunk = chunks_in_use(i);
1702 while (chunk != NULL) {
1703 // Just changed this sum += chunk->capacity_word_size();
1704 // sum += chunk->word_size() - Metachunk::overhead();
1705 sum += chunk->capacity_word_size();
1706 chunk = chunk->next();
1707 }
1708 }
1709 return sum;
1710 }
1712 size_t SpaceManager::sum_count_in_chunks_in_use() {
1713 size_t count = 0;
1714 for (ChunkIndex i = SmallIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) {
1715 count = count + sum_count_in_chunks_in_use(i);
1716 }
1718 return count;
1719 }
1721 size_t SpaceManager::sum_count_in_chunks_in_use(ChunkIndex i) {
1722 size_t count = 0;
1723 Metachunk* chunk = chunks_in_use(i);
1724 while (chunk != NULL) {
1725 count++;
1726 chunk = chunk->next();
1727 }
1728 return count;
1729 }
1732 size_t SpaceManager::sum_used_in_chunks_in_use() const {
1733 MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag);
1734 size_t used = 0;
1735 for (ChunkIndex i = SmallIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) {
1736 Metachunk* chunk = chunks_in_use(i);
1737 while (chunk != NULL) {
1738 used += chunk->used_word_size();
1739 chunk = chunk->next();
1740 }
1741 }
1742 return used;
1743 }
1745 void SpaceManager::locked_print_chunks_in_use_on(outputStream* st) const {
1747 Metachunk* small_chunk = chunks_in_use(SmallIndex);
1748 st->print_cr("SpaceManager: small chunk " PTR_FORMAT
1749 " free " SIZE_FORMAT,
1750 small_chunk,
1751 small_chunk->free_word_size());
1753 Metachunk* medium_chunk = chunks_in_use(MediumIndex);
1754 st->print("medium chunk " PTR_FORMAT, medium_chunk);
1755 Metachunk* tail = current_chunk();
1756 st->print_cr(" current chunk " PTR_FORMAT, tail);
1758 Metachunk* head = chunks_in_use(HumongousIndex);
1759 st->print_cr("humongous chunk " PTR_FORMAT, head);
1761 vs_list()->chunk_manager()->locked_print_free_chunks(st);
1762 vs_list()->chunk_manager()->locked_print_sum_free_chunks(st);
1763 }
1765 size_t SpaceManager::calc_chunk_size(size_t word_size) {
1767 // Decide between a small chunk and a medium chunk. Up to
1768 // _small_chunk_limit small chunks can be allocated but
1769 // once a medium chunk has been allocated, no more small
1770 // chunks will be allocated.
1771 size_t chunk_word_size;
1772 if (chunks_in_use(MediumIndex) == NULL &&
1773 (!has_small_chunk_limit() ||
1774 sum_count_in_chunks_in_use(SmallIndex) < _small_chunk_limit)) {
1775 chunk_word_size = (size_t) SpaceManager::SmallChunk;
1776 if (word_size + Metachunk::overhead() > SpaceManager::SmallChunk) {
1777 chunk_word_size = MediumChunk;
1778 }
1779 } else {
1780 chunk_word_size = MediumChunk;
1781 }
1783 // Might still need a humongous chunk
1784 chunk_word_size =
1785 MAX2((size_t) chunk_word_size, word_size + Metachunk::overhead());
1787 if (TraceMetadataHumongousAllocation &&
1788 SpaceManager::is_humongous(word_size)) {
1789 gclog_or_tty->print_cr("Metadata humongous allocation:");
1790 gclog_or_tty->print_cr(" word_size " PTR_FORMAT, word_size);
1791 gclog_or_tty->print_cr(" chunk_word_size " PTR_FORMAT,
1792 chunk_word_size);
1793 gclog_or_tty->print_cr(" chunk overhead " PTR_FORMAT,
1794 Metachunk::overhead());
1795 }
1796 return chunk_word_size;
1797 }
1799 MetaWord* SpaceManager::grow_and_allocate(size_t word_size) {
1800 assert(vs_list()->current_virtual_space() != NULL,
1801 "Should have been set");
1802 assert(current_chunk() == NULL ||
1803 current_chunk()->allocate(word_size) == NULL,
1804 "Don't need to expand");
1805 MutexLockerEx cl(SpaceManager::expand_lock(), Mutex::_no_safepoint_check_flag);
1807 if (TraceMetadataChunkAllocation && Verbose) {
1808 gclog_or_tty->print_cr("SpaceManager::grow_and_allocate for " SIZE_FORMAT
1809 " words " SIZE_FORMAT " space left",
1810 word_size, current_chunk() != NULL ?
1811 current_chunk()->free_word_size() : 0);
1812 }
1814 // Get another chunk out of the virtual space
1815 size_t grow_chunks_by_words = calc_chunk_size(word_size);
1816 Metachunk* next = vs_list()->get_new_chunk(word_size, grow_chunks_by_words);
1818 // If a chunk was available, add it to the in-use chunk list
1819 // and do an allocation from it.
1820 if (next != NULL) {
1821 Metadebug::deallocate_chunk_a_lot(this, grow_chunks_by_words);
1822 // Add to this manager's list of chunks in use.
1823 add_chunk(next, false);
1824 return next->allocate(word_size);
1825 }
1826 return NULL;
1827 }
1829 void SpaceManager::print_on(outputStream* st) const {
1831 for (ChunkIndex i = SmallIndex;
1832 i < NumberOfInUseLists ;
1833 i = next_chunk_index(i) ) {
1834 st->print_cr(" chunks_in_use " PTR_FORMAT " chunk size " PTR_FORMAT,
1835 chunks_in_use(i),
1836 chunks_in_use(i) == NULL ? 0 : chunks_in_use(i)->word_size());
1837 }
1838 st->print_cr(" waste: Small " SIZE_FORMAT " Medium " SIZE_FORMAT
1839 " Humongous " SIZE_FORMAT,
1840 sum_waste_in_chunks_in_use(SmallIndex),
1841 sum_waste_in_chunks_in_use(MediumIndex),
1842 sum_waste_in_chunks_in_use(HumongousIndex));
1843 // block free lists
1844 if (block_freelists() != NULL) {
1845 st->print_cr("total in block free lists " SIZE_FORMAT,
1846 block_freelists()->total_size());
1847 }
1848 }
1850 SpaceManager::SpaceManager(Mutex* lock, VirtualSpaceList* vs_list) :
1851 _vs_list(vs_list),
1852 _allocation_total(0),
1853 _lock(lock) {
1854 Metadebug::init_allocation_fail_alot_count();
1855 for (ChunkIndex i = SmallIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) {
1856 _chunks_in_use[i] = NULL;
1857 }
1858 _current_chunk = NULL;
1859 if (TraceMetadataChunkAllocation && Verbose) {
1860 gclog_or_tty->print_cr("SpaceManager(): " PTR_FORMAT, this);
1861 }
1862 }
1864 SpaceManager::~SpaceManager() {
1865 MutexLockerEx fcl(SpaceManager::expand_lock(),
1866 Mutex::_no_safepoint_check_flag);
1868 ChunkManager* chunk_manager = vs_list()->chunk_manager();
1870 chunk_manager->slow_locked_verify();
1872 if (TraceMetadataChunkAllocation && Verbose) {
1873 gclog_or_tty->print_cr("~SpaceManager(): " PTR_FORMAT, this);
1874 locked_print_chunks_in_use_on(gclog_or_tty);
1875 }
1877 // Mangle freed memory.
1878 NOT_PRODUCT(mangle_freed_chunks();)
1880 // Have to update before the chunks_in_use lists are emptied
1881 // below.
1882 chunk_manager->inc_free_chunks_total(sum_capacity_in_chunks_in_use(),
1883 sum_count_in_chunks_in_use());
1885 // Add all the chunks in use by this space manager
1886 // to the global list of free chunks.
1888 // Small chunks. There is one _current_chunk for each
1889 // Metaspace. It could point to a small or medium chunk.
1890 // Rather than determine which it is, follow the list of
1891 // small chunks to add them to the free list
1892 Metachunk* small_chunk = chunks_in_use(SmallIndex);
1893 chunk_manager->free_small_chunks()->add_at_head(small_chunk);
1894 set_chunks_in_use(SmallIndex, NULL);
1896 // After the small chunk are the medium chunks
1897 Metachunk* medium_chunk = chunks_in_use(MediumIndex);
1898 assert(medium_chunk == NULL ||
1899 medium_chunk->word_size() == MediumChunk,
1900 "Chunk is on the wrong list");
1902 if (medium_chunk != NULL) {
1903 Metachunk* head = medium_chunk;
1904 // If there is a medium chunk then the _current_chunk can only
1905 // point to the last medium chunk.
1906 Metachunk* tail = current_chunk();
1907 chunk_manager->free_medium_chunks()->add_at_head(head, tail);
1908 set_chunks_in_use(MediumIndex, NULL);
1909 }
1911 // Humongous chunks
1912 // Humongous chunks are never the current chunk.
1913 Metachunk* humongous_chunks = chunks_in_use(HumongousIndex);
1915 while (humongous_chunks != NULL) {
1916 #ifdef ASSERT
1917 humongous_chunks->set_is_free(true);
1918 #endif
1919 Metachunk* next_humongous_chunks = humongous_chunks->next();
1920 chunk_manager->humongous_dictionary()->return_chunk(humongous_chunks);
1921 humongous_chunks = next_humongous_chunks;
1922 }
1923 set_chunks_in_use(HumongousIndex, NULL);
1924 chunk_manager->slow_locked_verify();
1925 }
1927 void SpaceManager::deallocate(MetaWord* p, size_t word_size) {
1928 assert_lock_strong(_lock);
1929 size_t min_size = TreeChunk<Metablock, FreeList>::min_size();
1930 assert(word_size >= min_size,
1931 err_msg("Should not deallocate dark matter " SIZE_FORMAT, word_size));
1932 block_freelists()->return_block(p, word_size);
1933 }
1935 // Adds a chunk to the list of chunks in use.
1936 void SpaceManager::add_chunk(Metachunk* new_chunk, bool make_current) {
1938 assert(new_chunk != NULL, "Should not be NULL");
1939 assert(new_chunk->next() == NULL, "Should not be on a list");
1941 new_chunk->reset_empty();
1943 // Find the correct list and and set the current
1944 // chunk for that list.
1945 switch (new_chunk->word_size()) {
1946 case SpaceManager::SmallChunk :
1947 if (chunks_in_use(SmallIndex) == NULL) {
1948 // First chunk to add to the list
1949 set_chunks_in_use(SmallIndex, new_chunk);
1950 } else {
1951 assert(current_chunk()->word_size() == SpaceManager::SmallChunk,
1952 err_msg( "Incorrect mix of sizes in chunk list "
1953 SIZE_FORMAT " new chunk " SIZE_FORMAT,
1954 current_chunk()->word_size(), new_chunk->word_size()));
1955 current_chunk()->set_next(new_chunk);
1956 }
1957 // Make current chunk
1958 set_current_chunk(new_chunk);
1959 break;
1960 case SpaceManager::MediumChunk :
1961 if (chunks_in_use(MediumIndex) == NULL) {
1962 // About to add the first medium chunk so teminate the
1963 // small chunk list. In general once medium chunks are
1964 // being added, we're past the need for small chunks.
1965 if (current_chunk() != NULL) {
1966 // Only a small chunk or the initial chunk could be
1967 // the current chunk if this is the first medium chunk.
1968 assert(current_chunk()->word_size() == SpaceManager::SmallChunk ||
1969 chunks_in_use(SmallIndex) == NULL,
1970 err_msg("Should be a small chunk or initial chunk, current chunk "
1971 SIZE_FORMAT " new chunk " SIZE_FORMAT,
1972 current_chunk()->word_size(), new_chunk->word_size()));
1973 current_chunk()->set_next(NULL);
1974 }
1975 // First chunk to add to the list
1976 set_chunks_in_use(MediumIndex, new_chunk);
1978 } else {
1979 // As a minimum the first medium chunk added would
1980 // have become the _current_chunk
1981 // so the _current_chunk has to be non-NULL here
1982 // (although not necessarily still the first medium chunk).
1983 assert(current_chunk()->word_size() == SpaceManager::MediumChunk,
1984 "A medium chunk should the current chunk");
1985 current_chunk()->set_next(new_chunk);
1986 }
1987 // Make current chunk
1988 set_current_chunk(new_chunk);
1989 break;
1990 default: {
1991 // For null class loader data and DumpSharedSpaces, the first chunk isn't
1992 // small, so small will be null. Link this first chunk as the current
1993 // chunk.
1994 if (make_current) {
1995 // Set as the current chunk but otherwise treat as a humongous chunk.
1996 set_current_chunk(new_chunk);
1997 }
1998 // Link at head. The _current_chunk only points to a humongous chunk for
1999 // the null class loader metaspace (class and data virtual space managers)
2000 // any humongous chunks so will not point to the tail
2001 // of the humongous chunks list.
2002 new_chunk->set_next(chunks_in_use(HumongousIndex));
2003 set_chunks_in_use(HumongousIndex, new_chunk);
2005 assert(new_chunk->word_size() > MediumChunk, "List inconsistency");
2006 }
2007 }
2009 assert(new_chunk->is_empty(), "Not ready for reuse");
2010 if (TraceMetadataChunkAllocation && Verbose) {
2011 gclog_or_tty->print("SpaceManager::add_chunk: %d) ",
2012 sum_count_in_chunks_in_use());
2013 new_chunk->print_on(gclog_or_tty);
2014 vs_list()->chunk_manager()->locked_print_free_chunks(tty);
2015 }
2016 }
2018 MetaWord* SpaceManager::allocate(size_t word_size) {
2019 MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag);
2021 // If only the dictionary is going to be used (i.e., no
2022 // indexed free list), then there is a minimum size requirement.
2023 // MinChunkSize is a placeholder for the real minimum size JJJ
2024 size_t byte_size = word_size * BytesPerWord;
2026 size_t byte_size_with_overhead = byte_size + Metablock::overhead();
2028 size_t raw_bytes_size = MAX2(byte_size_with_overhead,
2029 Metablock::min_block_byte_size());
2030 raw_bytes_size = ARENA_ALIGN(raw_bytes_size);
2031 size_t raw_word_size = raw_bytes_size / BytesPerWord;
2032 assert(raw_word_size * BytesPerWord == raw_bytes_size, "Size problem");
2034 BlockFreelist* fl = block_freelists();
2035 MetaWord* p = NULL;
2036 // Allocation from the dictionary is expensive in the sense that
2037 // the dictionary has to be searched for a size. Don't allocate
2038 // from the dictionary until it starts to get fat. Is this
2039 // a reasonable policy? Maybe an skinny dictionary is fast enough
2040 // for allocations. Do some profiling. JJJ
2041 if (fl->total_size() > allocation_from_dictionary_limit) {
2042 p = fl->get_block(raw_word_size);
2043 }
2044 if (p == NULL) {
2045 p = allocate_work(raw_word_size);
2046 }
2047 Metadebug::deallocate_block_a_lot(this, raw_word_size);
2049 return p;
2050 }
2052 // Returns the address of spaced allocated for "word_size".
2053 // This methods does not know about blocks (Metablocks)
2054 MetaWord* SpaceManager::allocate_work(size_t word_size) {
2055 assert_lock_strong(_lock);
2056 #ifdef ASSERT
2057 if (Metadebug::test_metadata_failure()) {
2058 return NULL;
2059 }
2060 #endif
2061 // Is there space in the current chunk?
2062 MetaWord* result = NULL;
2064 // For DumpSharedSpaces, only allocate out of the current chunk which is
2065 // never null because we gave it the size we wanted. Caller reports out
2066 // of memory if this returns null.
2067 if (DumpSharedSpaces) {
2068 assert(current_chunk() != NULL, "should never happen");
2069 inc_allocation_total(word_size);
2070 return current_chunk()->allocate(word_size); // caller handles null result
2071 }
2072 if (current_chunk() != NULL) {
2073 result = current_chunk()->allocate(word_size);
2074 }
2076 if (result == NULL) {
2077 result = grow_and_allocate(word_size);
2078 }
2079 if (result > 0) {
2080 inc_allocation_total(word_size);
2081 assert(result != (MetaWord*) chunks_in_use(MediumIndex),
2082 "Head of the list is being allocated");
2083 }
2085 return result;
2086 }
2088 void SpaceManager::verify() {
2089 // If there are blocks in the dictionary, then
2090 // verfication of chunks does not work since
2091 // being in the dictionary alters a chunk.
2092 if (block_freelists()->total_size() == 0) {
2093 // Skip the small chunks because their next link points to
2094 // medium chunks. This is because the small chunk is the
2095 // current chunk (for allocations) until it is full and the
2096 // the addition of the next chunk does not NULL the next
2097 // like of the small chunk.
2098 for (ChunkIndex i = MediumIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) {
2099 Metachunk* curr = chunks_in_use(i);
2100 while (curr != NULL) {
2101 curr->verify();
2102 verify_chunk_size(curr);
2103 curr = curr->next();
2104 }
2105 }
2106 }
2107 }
2109 void SpaceManager::verify_chunk_size(Metachunk* chunk) {
2110 assert(is_humongous(chunk->word_size()) ||
2111 chunk->word_size() == MediumChunk ||
2112 chunk->word_size() == SmallChunk,
2113 "Chunk size is wrong");
2114 return;
2115 }
2117 #ifdef ASSERT
2118 void SpaceManager::verify_allocation_total() {
2119 #if 0
2120 // Verification is only guaranteed at a safepoint.
2121 if (SafepointSynchronize::is_at_safepoint()) {
2122 gclog_or_tty->print_cr("Chunk " PTR_FORMAT " allocation_total " SIZE_FORMAT
2123 " sum_used_in_chunks_in_use " SIZE_FORMAT,
2124 this,
2125 allocation_total(),
2126 sum_used_in_chunks_in_use());
2127 }
2128 MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag);
2129 assert(allocation_total() == sum_used_in_chunks_in_use(),
2130 err_msg("allocation total is not consistent %d vs %d",
2131 allocation_total(), sum_used_in_chunks_in_use()));
2132 #endif
2133 }
2135 #endif
2137 void SpaceManager::dump(outputStream* const out) const {
2138 size_t curr_total = 0;
2139 size_t waste = 0;
2140 uint i = 0;
2141 size_t used = 0;
2142 size_t capacity = 0;
2144 // Add up statistics for all chunks in this SpaceManager.
2145 for (ChunkIndex index = SmallIndex;
2146 index < NumberOfInUseLists;
2147 index = next_chunk_index(index)) {
2148 for (Metachunk* curr = chunks_in_use(index);
2149 curr != NULL;
2150 curr = curr->next()) {
2151 out->print("%d) ", i++);
2152 curr->print_on(out);
2153 if (TraceMetadataChunkAllocation && Verbose) {
2154 block_freelists()->print_on(out);
2155 }
2156 curr_total += curr->word_size();
2157 used += curr->used_word_size();
2158 capacity += curr->capacity_word_size();
2159 waste += curr->free_word_size() + curr->overhead();;
2160 }
2161 }
2163 size_t free = current_chunk()->free_word_size();
2164 // Free space isn't wasted.
2165 waste -= free;
2167 out->print_cr("total of all chunks " SIZE_FORMAT " used " SIZE_FORMAT
2168 " free " SIZE_FORMAT " capacity " SIZE_FORMAT
2169 " waste " SIZE_FORMAT, curr_total, used, free, capacity, waste);
2170 }
2172 #ifndef PRODUCT
2173 void SpaceManager::mangle_freed_chunks() {
2174 for (ChunkIndex index = SmallIndex;
2175 index < NumberOfInUseLists;
2176 index = next_chunk_index(index)) {
2177 for (Metachunk* curr = chunks_in_use(index);
2178 curr != NULL;
2179 curr = curr->next()) {
2180 // Try to detect incorrectly terminated small chunk
2181 // list.
2182 assert(index == MediumIndex || curr != chunks_in_use(MediumIndex),
2183 err_msg("Mangling medium chunks in small chunks? "
2184 "curr " PTR_FORMAT " medium list " PTR_FORMAT,
2185 curr, chunks_in_use(MediumIndex)));
2186 curr->mangle();
2187 }
2188 }
2189 }
2190 #endif // PRODUCT
2193 // MetaspaceAux
2195 size_t MetaspaceAux::used_in_bytes(Metaspace::MetadataType mdtype) {
2196 size_t used = 0;
2197 ClassLoaderDataGraphMetaspaceIterator iter;
2198 while (iter.repeat()) {
2199 Metaspace* msp = iter.get_next();
2200 // Sum allocation_total for each metaspace
2201 if (msp != NULL) {
2202 used += msp->used_words(mdtype);
2203 }
2204 }
2205 return used * BytesPerWord;
2206 }
2208 size_t MetaspaceAux::free_in_bytes(Metaspace::MetadataType mdtype) {
2209 size_t free = 0;
2210 ClassLoaderDataGraphMetaspaceIterator iter;
2211 while (iter.repeat()) {
2212 Metaspace* msp = iter.get_next();
2213 if (msp != NULL) {
2214 free += msp->free_words(mdtype);
2215 }
2216 }
2217 return free * BytesPerWord;
2218 }
2220 size_t MetaspaceAux::capacity_in_bytes(Metaspace::MetadataType mdtype) {
2221 size_t capacity = free_chunks_total(mdtype);
2222 ClassLoaderDataGraphMetaspaceIterator iter;
2223 while (iter.repeat()) {
2224 Metaspace* msp = iter.get_next();
2225 if (msp != NULL) {
2226 capacity += msp->capacity_words(mdtype);
2227 }
2228 }
2229 return capacity * BytesPerWord;
2230 }
2232 size_t MetaspaceAux::reserved_in_bytes(Metaspace::MetadataType mdtype) {
2233 size_t reserved = (mdtype == Metaspace::ClassType) ?
2234 Metaspace::class_space_list()->virtual_space_total() :
2235 Metaspace::space_list()->virtual_space_total();
2236 return reserved * BytesPerWord;
2237 }
2239 size_t MetaspaceAux::min_chunk_size() { return SpaceManager::MediumChunk; }
2241 size_t MetaspaceAux::free_chunks_total(Metaspace::MetadataType mdtype) {
2242 ChunkManager* chunk = (mdtype == Metaspace::ClassType) ?
2243 Metaspace::class_space_list()->chunk_manager() :
2244 Metaspace::space_list()->chunk_manager();
2245 chunk->slow_verify();
2246 return chunk->free_chunks_total();
2247 }
2249 size_t MetaspaceAux::free_chunks_total_in_bytes(Metaspace::MetadataType mdtype) {
2250 return free_chunks_total(mdtype) * BytesPerWord;
2251 }
2253 void MetaspaceAux::print_metaspace_change(size_t prev_metadata_used) {
2254 gclog_or_tty->print(", [Metaspace:");
2255 if (PrintGCDetails && Verbose) {
2256 gclog_or_tty->print(" " SIZE_FORMAT
2257 "->" SIZE_FORMAT
2258 "(" SIZE_FORMAT "/" SIZE_FORMAT ")",
2259 prev_metadata_used,
2260 used_in_bytes(),
2261 capacity_in_bytes(),
2262 reserved_in_bytes());
2263 } else {
2264 gclog_or_tty->print(" " SIZE_FORMAT "K"
2265 "->" SIZE_FORMAT "K"
2266 "(" SIZE_FORMAT "K/" SIZE_FORMAT "K)",
2267 prev_metadata_used / K,
2268 used_in_bytes()/ K,
2269 capacity_in_bytes()/K,
2270 reserved_in_bytes()/ K);
2271 }
2273 gclog_or_tty->print("]");
2274 }
2276 // This is printed when PrintGCDetails
2277 void MetaspaceAux::print_on(outputStream* out) {
2278 Metaspace::MetadataType ct = Metaspace::ClassType;
2279 Metaspace::MetadataType nct = Metaspace::NonClassType;
2281 out->print_cr(" Metaspace total "
2282 SIZE_FORMAT "K, used " SIZE_FORMAT "K,"
2283 " reserved " SIZE_FORMAT "K",
2284 capacity_in_bytes()/K, used_in_bytes()/K, reserved_in_bytes()/K);
2285 out->print_cr(" data space "
2286 SIZE_FORMAT "K, used " SIZE_FORMAT "K,"
2287 " reserved " SIZE_FORMAT "K",
2288 capacity_in_bytes(nct)/K, used_in_bytes(nct)/K, reserved_in_bytes(nct)/K);
2289 out->print_cr(" class space "
2290 SIZE_FORMAT "K, used " SIZE_FORMAT "K,"
2291 " reserved " SIZE_FORMAT "K",
2292 capacity_in_bytes(ct)/K, used_in_bytes(ct)/K, reserved_in_bytes(ct)/K);
2293 }
2295 // Print information for class space and data space separately.
2296 // This is almost the same as above.
2297 void MetaspaceAux::print_on(outputStream* out, Metaspace::MetadataType mdtype) {
2298 size_t free_chunks_capacity_bytes = free_chunks_total_in_bytes(mdtype);
2299 size_t capacity_bytes = capacity_in_bytes(mdtype);
2300 size_t used_bytes = used_in_bytes(mdtype);
2301 size_t free_bytes = free_in_bytes(mdtype);
2302 size_t used_and_free = used_bytes + free_bytes +
2303 free_chunks_capacity_bytes;
2304 out->print_cr(" Chunk accounting: used in chunks " SIZE_FORMAT
2305 "K + unused in chunks " SIZE_FORMAT "K + "
2306 " capacity in free chunks " SIZE_FORMAT "K = " SIZE_FORMAT
2307 "K capacity in allocated chunks " SIZE_FORMAT "K",
2308 used_bytes / K,
2309 free_bytes / K,
2310 free_chunks_capacity_bytes / K,
2311 used_and_free / K,
2312 capacity_bytes / K);
2313 assert(used_and_free == capacity_bytes, "Accounting is wrong");
2314 }
2316 // Print total fragmentation for class and data metaspaces separately
2317 void MetaspaceAux::print_waste(outputStream* out) {
2319 size_t small_waste = 0, medium_waste = 0, large_waste = 0;
2320 size_t cls_small_waste = 0, cls_medium_waste = 0, cls_large_waste = 0;
2322 ClassLoaderDataGraphMetaspaceIterator iter;
2323 while (iter.repeat()) {
2324 Metaspace* msp = iter.get_next();
2325 if (msp != NULL) {
2326 small_waste += msp->vsm()->sum_waste_in_chunks_in_use(SmallIndex);
2327 medium_waste += msp->vsm()->sum_waste_in_chunks_in_use(MediumIndex);
2328 large_waste += msp->vsm()->sum_waste_in_chunks_in_use(HumongousIndex);
2330 cls_small_waste += msp->class_vsm()->sum_waste_in_chunks_in_use(SmallIndex);
2331 cls_medium_waste += msp->class_vsm()->sum_waste_in_chunks_in_use(MediumIndex);
2332 cls_large_waste += msp->class_vsm()->sum_waste_in_chunks_in_use(HumongousIndex);
2333 }
2334 }
2335 out->print_cr("Total fragmentation waste (words) doesn't count free space");
2336 out->print(" data: small " SIZE_FORMAT " medium " SIZE_FORMAT,
2337 small_waste, medium_waste);
2338 out->print_cr(" class: small " SIZE_FORMAT, cls_small_waste);
2339 }
2341 // Dump global metaspace things from the end of ClassLoaderDataGraph
2342 void MetaspaceAux::dump(outputStream* out) {
2343 out->print_cr("All Metaspace:");
2344 out->print("data space: "); print_on(out, Metaspace::NonClassType);
2345 out->print("class space: "); print_on(out, Metaspace::ClassType);
2346 print_waste(out);
2347 }
2349 void MetaspaceAux::verify_free_chunks() {
2350 Metaspace::space_list()->chunk_manager()->verify();
2351 Metaspace::class_space_list()->chunk_manager()->verify();
2352 }
2354 // Metaspace methods
2356 size_t Metaspace::_first_chunk_word_size = 0;
2358 Metaspace::Metaspace(Mutex* lock, size_t word_size) {
2359 initialize(lock, word_size);
2360 }
2362 Metaspace::Metaspace(Mutex* lock) {
2363 initialize(lock);
2364 }
2366 Metaspace::~Metaspace() {
2367 delete _vsm;
2368 delete _class_vsm;
2369 }
2371 VirtualSpaceList* Metaspace::_space_list = NULL;
2372 VirtualSpaceList* Metaspace::_class_space_list = NULL;
2374 #define VIRTUALSPACEMULTIPLIER 2
2376 void Metaspace::global_initialize() {
2377 // Initialize the alignment for shared spaces.
2378 int max_alignment = os::vm_page_size();
2379 MetaspaceShared::set_max_alignment(max_alignment);
2381 if (DumpSharedSpaces) {
2382 SharedReadOnlySize = align_size_up(SharedReadOnlySize, max_alignment);
2383 SharedReadWriteSize = align_size_up(SharedReadWriteSize, max_alignment);
2384 SharedMiscDataSize = align_size_up(SharedMiscDataSize, max_alignment);
2385 SharedMiscCodeSize = align_size_up(SharedMiscCodeSize, max_alignment);
2387 // Initialize with the sum of the shared space sizes. The read-only
2388 // and read write metaspace chunks will be allocated out of this and the
2389 // remainder is the misc code and data chunks.
2390 size_t total = align_size_up(SharedReadOnlySize + SharedReadWriteSize +
2391 SharedMiscDataSize + SharedMiscCodeSize,
2392 os::vm_allocation_granularity());
2393 size_t word_size = total/wordSize;
2394 _space_list = new VirtualSpaceList(word_size);
2395 } else {
2396 // If using shared space, open the file that contains the shared space
2397 // and map in the memory before initializing the rest of metaspace (so
2398 // the addresses don't conflict)
2399 if (UseSharedSpaces) {
2400 FileMapInfo* mapinfo = new FileMapInfo();
2401 memset(mapinfo, 0, sizeof(FileMapInfo));
2403 // Open the shared archive file, read and validate the header. If
2404 // initialization fails, shared spaces [UseSharedSpaces] are
2405 // disabled and the file is closed.
2406 // Map in spaces now also
2407 if (mapinfo->initialize() && MetaspaceShared::map_shared_spaces(mapinfo)) {
2408 FileMapInfo::set_current_info(mapinfo);
2409 } else {
2410 assert(!mapinfo->is_open() && !UseSharedSpaces,
2411 "archive file not closed or shared spaces not disabled.");
2412 }
2413 }
2415 // Initialize this before initializing the VirtualSpaceList
2416 _first_chunk_word_size = InitialBootClassLoaderMetaspaceSize / BytesPerWord;
2417 // Arbitrarily set the initial virtual space to a multiple
2418 // of the boot class loader size.
2419 size_t word_size = VIRTUALSPACEMULTIPLIER * Metaspace::first_chunk_word_size();
2420 // Initialize the list of virtual spaces.
2421 _space_list = new VirtualSpaceList(word_size);
2422 }
2423 }
2425 // For UseCompressedKlassPointers the class space is reserved as a piece of the
2426 // Java heap because the compression algorithm is the same for each. The
2427 // argument passed in is at the top of the compressed space
2428 void Metaspace::initialize_class_space(ReservedSpace rs) {
2429 // The reserved space size may be bigger because of alignment, esp with UseLargePages
2430 assert(rs.size() >= ClassMetaspaceSize, err_msg("%d != %d", rs.size(), ClassMetaspaceSize));
2431 _class_space_list = new VirtualSpaceList(rs);
2432 }
2435 void Metaspace::initialize(Mutex* lock, size_t initial_size) {
2436 // Use SmallChunk size if not specified. If specified, use this size for
2437 // the data metaspace.
2438 size_t word_size;
2439 size_t class_word_size;
2440 if (initial_size == 0) {
2441 word_size = (size_t) SpaceManager::SmallChunk;
2442 class_word_size = (size_t) SpaceManager::SmallChunk;
2443 } else {
2444 word_size = initial_size;
2445 // Make the first class chunk bigger than a medium chunk so it's not put
2446 // on the medium chunk list. The next chunk will be small and progress
2447 // from there. This size calculated by -version.
2448 class_word_size = MIN2((size_t)SpaceManager::MediumChunk*5,
2449 (ClassMetaspaceSize/BytesPerWord)*2);
2450 }
2452 assert(space_list() != NULL,
2453 "Metadata VirtualSpaceList has not been initialized");
2455 _vsm = new SpaceManager(lock, space_list());
2456 if (_vsm == NULL) {
2457 return;
2458 }
2460 assert(class_space_list() != NULL,
2461 "Class VirtualSpaceList has not been initialized");
2463 // Allocate SpaceManager for classes.
2464 _class_vsm = new SpaceManager(lock, class_space_list());
2465 if (_class_vsm == NULL) {
2466 return;
2467 }
2469 MutexLockerEx cl(SpaceManager::expand_lock(), Mutex::_no_safepoint_check_flag);
2471 // Allocate chunk for metadata objects
2472 Metachunk* new_chunk =
2473 space_list()->current_virtual_space()->get_chunk_vs_with_expand(word_size);
2474 assert(!DumpSharedSpaces || new_chunk != NULL, "should have enough space for both chunks");
2475 if (new_chunk != NULL) {
2476 // Add to this manager's list of chunks in use and current_chunk().
2477 vsm()->add_chunk(new_chunk, true);
2478 }
2480 // Allocate chunk for class metadata objects
2481 Metachunk* class_chunk =
2482 class_space_list()->current_virtual_space()->get_chunk_vs_with_expand(class_word_size);
2483 if (class_chunk != NULL) {
2484 class_vsm()->add_chunk(class_chunk, true);
2485 }
2486 }
2488 MetaWord* Metaspace::allocate(size_t word_size, MetadataType mdtype) {
2489 // DumpSharedSpaces doesn't use class metadata area (yet)
2490 if (mdtype == ClassType && !DumpSharedSpaces) {
2491 return class_vsm()->allocate(word_size);
2492 } else {
2493 return vsm()->allocate(word_size);
2494 }
2495 }
2497 MetaWord* Metaspace::expand_and_allocate(size_t word_size, MetadataType mdtype) {
2498 MetaWord* result;
2499 MetaspaceGC::set_expand_after_GC(true);
2500 size_t before_inc = MetaspaceGC::capacity_until_GC();
2501 size_t delta_words = MetaspaceGC::delta_capacity_until_GC(word_size);
2502 MetaspaceGC::inc_capacity_until_GC(delta_words);
2503 if (PrintGCDetails && Verbose) {
2504 gclog_or_tty->print_cr("Increase capacity to GC from " SIZE_FORMAT
2505 " to " SIZE_FORMAT, before_inc, MetaspaceGC::capacity_until_GC());
2506 }
2508 result = allocate(word_size, mdtype);
2510 return result;
2511 }
2513 // Space allocated in the Metaspace. This may
2514 // be across several metadata virtual spaces.
2515 char* Metaspace::bottom() const {
2516 assert(DumpSharedSpaces, "only useful and valid for dumping shared spaces");
2517 return (char*)vsm()->current_chunk()->bottom();
2518 }
2520 size_t Metaspace::used_words(MetadataType mdtype) const {
2521 // return vsm()->allocation_total();
2522 return mdtype == ClassType ? class_vsm()->sum_used_in_chunks_in_use() :
2523 vsm()->sum_used_in_chunks_in_use(); // includes overhead!
2524 }
2526 size_t Metaspace::free_words(MetadataType mdtype) const {
2527 return mdtype == ClassType ? class_vsm()->sum_free_in_chunks_in_use() :
2528 vsm()->sum_free_in_chunks_in_use();
2529 }
2531 // Space capacity in the Metaspace. It includes
2532 // space in the list of chunks from which allocations
2533 // have been made. Don't include space in the global freelist and
2534 // in the space available in the dictionary which
2535 // is already counted in some chunk.
2536 size_t Metaspace::capacity_words(MetadataType mdtype) const {
2537 return mdtype == ClassType ? class_vsm()->sum_capacity_in_chunks_in_use() :
2538 vsm()->sum_capacity_in_chunks_in_use();
2539 }
2541 void Metaspace::deallocate(MetaWord* ptr, size_t word_size, bool is_class) {
2542 if (SafepointSynchronize::is_at_safepoint()) {
2543 assert(Thread::current()->is_VM_thread(), "should be the VM thread");
2544 // Don't take Heap_lock
2545 MutexLocker ml(vsm()->lock());
2546 if (word_size < TreeChunk<Metablock, FreeList>::min_size()) {
2547 // Dark matter. Too small for dictionary.
2548 #ifdef ASSERT
2549 Copy::fill_to_words((HeapWord*)ptr, word_size, 0xf5f5f5f5);
2550 #endif
2551 return;
2552 }
2553 if (is_class) {
2554 class_vsm()->deallocate(ptr, word_size);
2555 } else {
2556 vsm()->deallocate(ptr, word_size);
2557 }
2558 } else {
2559 MutexLocker ml(vsm()->lock());
2561 if (word_size < TreeChunk<Metablock, FreeList>::min_size()) {
2562 // Dark matter. Too small for dictionary.
2563 #ifdef ASSERT
2564 Copy::fill_to_words((HeapWord*)ptr, word_size, 0xf5f5f5f5);
2565 #endif
2566 return;
2567 }
2568 if (is_class) {
2569 class_vsm()->deallocate(ptr, word_size);
2570 } else {
2571 vsm()->deallocate(ptr, word_size);
2572 }
2573 }
2574 }
2576 Metablock* Metaspace::allocate(ClassLoaderData* loader_data, size_t word_size,
2577 bool read_only, MetadataType mdtype, TRAPS) {
2578 if (HAS_PENDING_EXCEPTION) {
2579 assert(false, "Should not allocate with exception pending");
2580 return NULL; // caller does a CHECK_NULL too
2581 }
2583 // SSS: Should we align the allocations and make sure the sizes are aligned.
2584 MetaWord* result = NULL;
2586 assert(loader_data != NULL, "Should never pass around a NULL loader_data. "
2587 "ClassLoaderData::the_null_class_loader_data() should have been used.");
2588 // Allocate in metaspaces without taking out a lock, because it deadlocks
2589 // with the SymbolTable_lock. Dumping is single threaded for now. We'll have
2590 // to revisit this for application class data sharing.
2591 if (DumpSharedSpaces) {
2592 if (read_only) {
2593 result = loader_data->ro_metaspace()->allocate(word_size, NonClassType);
2594 } else {
2595 result = loader_data->rw_metaspace()->allocate(word_size, NonClassType);
2596 }
2597 if (result == NULL) {
2598 report_out_of_shared_space(read_only ? SharedReadOnly : SharedReadWrite);
2599 }
2600 return Metablock::initialize(result, word_size);
2601 }
2603 result = loader_data->metaspace_non_null()->allocate(word_size, mdtype);
2605 if (result == NULL) {
2606 // Try to clean out some memory and retry.
2607 result =
2608 Universe::heap()->collector_policy()->satisfy_failed_metadata_allocation(
2609 loader_data, word_size, mdtype);
2611 // If result is still null, we are out of memory.
2612 if (result == NULL) {
2613 // -XX:+HeapDumpOnOutOfMemoryError and -XX:OnOutOfMemoryError support
2614 report_java_out_of_memory("Metadata space");
2616 if (JvmtiExport::should_post_resource_exhausted()) {
2617 JvmtiExport::post_resource_exhausted(
2618 JVMTI_RESOURCE_EXHAUSTED_OOM_ERROR,
2619 "Metadata space");
2620 }
2621 THROW_OOP_0(Universe::out_of_memory_error_perm_gen());
2622 }
2623 }
2624 return Metablock::initialize(result, word_size);
2625 }
2627 void Metaspace::print_on(outputStream* out) const {
2628 // Print both class virtual space counts and metaspace.
2629 if (Verbose) {
2630 vsm()->print_on(out);
2631 class_vsm()->print_on(out);
2632 }
2633 }
2635 bool Metaspace::contains(const void * ptr) {
2636 if (MetaspaceShared::is_in_shared_space(ptr)) {
2637 return true;
2638 }
2639 // This is checked while unlocked. As long as the virtualspaces are added
2640 // at the end, the pointer will be in one of them. The virtual spaces
2641 // aren't deleted presently. When they are, some sort of locking might
2642 // be needed. Note, locking this can cause inversion problems with the
2643 // caller in MetaspaceObj::is_metadata() function.
2644 return space_list()->contains(ptr) || class_space_list()->contains(ptr);
2645 }
2647 void Metaspace::verify() {
2648 vsm()->verify();
2649 class_vsm()->verify();
2650 }
2652 void Metaspace::dump(outputStream* const out) const {
2653 if (UseMallocOnly) {
2654 // Just print usage for now
2655 out->print_cr("usage %d", used_words(Metaspace::NonClassType));
2656 }
2657 out->print_cr("\nVirtual space manager: " INTPTR_FORMAT, vsm());
2658 vsm()->dump(out);
2659 out->print_cr("\nClass space manager: " INTPTR_FORMAT, class_vsm());
2660 class_vsm()->dump(out);
2661 }