src/share/vm/memory/metaspace.cpp

Tue, 29 May 2018 20:20:25 +0800

author
aoqi
date
Tue, 29 May 2018 20:20:25 +0800
changeset 9122
024be04bb151
parent 9064
ea0367ce6726
parent 9041
95a08233f46c
child 9268
acf02173a790
permissions
-rw-r--r--

Merge

     1 /*
     2  * Copyright (c) 2011, 2018, Oracle and/or its affiliates. All rights reserved.
     3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
     4  *
     5  * This code is free software; you can redistribute it and/or modify it
     6  * under the terms of the GNU General Public License version 2 only, as
     7  * published by the Free Software Foundation.
     8  *
     9  * This code is distributed in the hope that it will be useful, but WITHOUT
    10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
    11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
    12  * version 2 for more details (a copy is included in the LICENSE file that
    13  * accompanied this code).
    14  *
    15  * You should have received a copy of the GNU General Public License version
    16  * 2 along with this work; if not, write to the Free Software Foundation,
    17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
    18  *
    19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
    20  * or visit www.oracle.com if you need additional information or have any
    21  * questions.
    22  *
    23  */
    24 #include "precompiled.hpp"
    25 #include "gc_interface/collectedHeap.hpp"
    26 #include "memory/allocation.hpp"
    27 #include "memory/binaryTreeDictionary.hpp"
    28 #include "memory/freeList.hpp"
    29 #include "memory/collectorPolicy.hpp"
    30 #include "memory/filemap.hpp"
    31 #include "memory/freeList.hpp"
    32 #include "memory/gcLocker.hpp"
    33 #include "memory/metachunk.hpp"
    34 #include "memory/metaspace.hpp"
    35 #include "memory/metaspaceGCThresholdUpdater.hpp"
    36 #include "memory/metaspaceShared.hpp"
    37 #include "memory/metaspaceTracer.hpp"
    38 #include "memory/resourceArea.hpp"
    39 #include "memory/universe.hpp"
    40 #include "runtime/atomic.inline.hpp"
    41 #include "runtime/globals.hpp"
    42 #include "runtime/init.hpp"
    43 #include "runtime/java.hpp"
    44 #include "runtime/mutex.hpp"
    45 #include "runtime/orderAccess.inline.hpp"
    46 #include "services/memTracker.hpp"
    47 #include "services/memoryService.hpp"
    48 #include "utilities/copy.hpp"
    49 #include "utilities/debug.hpp"
    51 PRAGMA_FORMAT_MUTE_WARNINGS_FOR_GCC
    53 typedef BinaryTreeDictionary<Metablock, FreeList<Metablock> > BlockTreeDictionary;
    54 typedef BinaryTreeDictionary<Metachunk, FreeList<Metachunk> > ChunkTreeDictionary;
    56 // Set this constant to enable slow integrity checking of the free chunk lists
    57 const bool metaspace_slow_verify = false;
    59 size_t const allocation_from_dictionary_limit = 4 * K;
    61 MetaWord* last_allocated = 0;
    63 size_t Metaspace::_compressed_class_space_size;
    64 const MetaspaceTracer* Metaspace::_tracer = NULL;
    66 // Used in declarations in SpaceManager and ChunkManager
    67 enum ChunkIndex {
    68   ZeroIndex = 0,
    69   SpecializedIndex = ZeroIndex,
    70   SmallIndex = SpecializedIndex + 1,
    71   MediumIndex = SmallIndex + 1,
    72   HumongousIndex = MediumIndex + 1,
    73   NumberOfFreeLists = 3,
    74   NumberOfInUseLists = 4
    75 };
    77 enum ChunkSizes {    // in words.
    78   ClassSpecializedChunk = 128,
    79   SpecializedChunk = 128,
    80   ClassSmallChunk = 256,
    81   SmallChunk = 512,
    82   ClassMediumChunk = 4 * K,
    83   MediumChunk = 8 * K
    84 };
    86 static ChunkIndex next_chunk_index(ChunkIndex i) {
    87   assert(i < NumberOfInUseLists, "Out of bound");
    88   return (ChunkIndex) (i+1);
    89 }
    91 volatile intptr_t MetaspaceGC::_capacity_until_GC = 0;
    92 uint MetaspaceGC::_shrink_factor = 0;
    93 bool MetaspaceGC::_should_concurrent_collect = false;
    95 typedef class FreeList<Metachunk> ChunkList;
    97 // Manages the global free lists of chunks.
    98 class ChunkManager : public CHeapObj<mtInternal> {
    99   friend class TestVirtualSpaceNodeTest;
   101   // Free list of chunks of different sizes.
   102   //   SpecializedChunk
   103   //   SmallChunk
   104   //   MediumChunk
   105   //   HumongousChunk
   106   ChunkList _free_chunks[NumberOfFreeLists];
   108   //   HumongousChunk
   109   ChunkTreeDictionary _humongous_dictionary;
   111   // ChunkManager in all lists of this type
   112   size_t _free_chunks_total;
   113   size_t _free_chunks_count;
   115   void dec_free_chunks_total(size_t v) {
   116     assert(_free_chunks_count > 0 &&
   117              _free_chunks_total > 0,
   118              "About to go negative");
   119     Atomic::add_ptr(-1, &_free_chunks_count);
   120     jlong minus_v = (jlong) - (jlong) v;
   121     Atomic::add_ptr(minus_v, &_free_chunks_total);
   122   }
   124   // Debug support
   126   size_t sum_free_chunks();
   127   size_t sum_free_chunks_count();
   129   void locked_verify_free_chunks_total();
   130   void slow_locked_verify_free_chunks_total() {
   131     if (metaspace_slow_verify) {
   132       locked_verify_free_chunks_total();
   133     }
   134   }
   135   void locked_verify_free_chunks_count();
   136   void slow_locked_verify_free_chunks_count() {
   137     if (metaspace_slow_verify) {
   138       locked_verify_free_chunks_count();
   139     }
   140   }
   141   void verify_free_chunks_count();
   143  public:
   145   ChunkManager(size_t specialized_size, size_t small_size, size_t medium_size)
   146       : _free_chunks_total(0), _free_chunks_count(0) {
   147     _free_chunks[SpecializedIndex].set_size(specialized_size);
   148     _free_chunks[SmallIndex].set_size(small_size);
   149     _free_chunks[MediumIndex].set_size(medium_size);
   150   }
   152   // add or delete (return) a chunk to the global freelist.
   153   Metachunk* chunk_freelist_allocate(size_t word_size);
   155   // Map a size to a list index assuming that there are lists
   156   // for special, small, medium, and humongous chunks.
   157   ChunkIndex list_index(size_t size);
   159   // Remove the chunk from its freelist.  It is
   160   // expected to be on one of the _free_chunks[] lists.
   161   void remove_chunk(Metachunk* chunk);
   163   // Add the simple linked list of chunks to the freelist of chunks
   164   // of type index.
   165   void return_chunks(ChunkIndex index, Metachunk* chunks);
   167   // Total of the space in the free chunks list
   168   size_t free_chunks_total_words();
   169   size_t free_chunks_total_bytes();
   171   // Number of chunks in the free chunks list
   172   size_t free_chunks_count();
   174   void inc_free_chunks_total(size_t v, size_t count = 1) {
   175     Atomic::add_ptr(count, &_free_chunks_count);
   176     Atomic::add_ptr(v, &_free_chunks_total);
   177   }
   178   ChunkTreeDictionary* humongous_dictionary() {
   179     return &_humongous_dictionary;
   180   }
   182   ChunkList* free_chunks(ChunkIndex index);
   184   // Returns the list for the given chunk word size.
   185   ChunkList* find_free_chunks_list(size_t word_size);
   187   // Remove from a list by size.  Selects list based on size of chunk.
   188   Metachunk* free_chunks_get(size_t chunk_word_size);
   190 #define index_bounds_check(index)                                         \
   191   assert(index == SpecializedIndex ||                                     \
   192          index == SmallIndex ||                                           \
   193          index == MediumIndex ||                                          \
   194          index == HumongousIndex, err_msg("Bad index: %d", (int) index))
   196   size_t num_free_chunks(ChunkIndex index) const {
   197     index_bounds_check(index);
   199     if (index == HumongousIndex) {
   200       return _humongous_dictionary.total_free_blocks();
   201     }
   203     ssize_t count = _free_chunks[index].count();
   204     return count == -1 ? 0 : (size_t) count;
   205   }
   207   size_t size_free_chunks_in_bytes(ChunkIndex index) const {
   208     index_bounds_check(index);
   210     size_t word_size = 0;
   211     if (index == HumongousIndex) {
   212       word_size = _humongous_dictionary.total_size();
   213     } else {
   214       const size_t size_per_chunk_in_words = _free_chunks[index].size();
   215       word_size = size_per_chunk_in_words * num_free_chunks(index);
   216     }
   218     return word_size * BytesPerWord;
   219   }
   221   MetaspaceChunkFreeListSummary chunk_free_list_summary() const {
   222     return MetaspaceChunkFreeListSummary(num_free_chunks(SpecializedIndex),
   223                                          num_free_chunks(SmallIndex),
   224                                          num_free_chunks(MediumIndex),
   225                                          num_free_chunks(HumongousIndex),
   226                                          size_free_chunks_in_bytes(SpecializedIndex),
   227                                          size_free_chunks_in_bytes(SmallIndex),
   228                                          size_free_chunks_in_bytes(MediumIndex),
   229                                          size_free_chunks_in_bytes(HumongousIndex));
   230   }
   232   // Debug support
   233   void verify();
   234   void slow_verify() {
   235     if (metaspace_slow_verify) {
   236       verify();
   237     }
   238   }
   239   void locked_verify();
   240   void slow_locked_verify() {
   241     if (metaspace_slow_verify) {
   242       locked_verify();
   243     }
   244   }
   245   void verify_free_chunks_total();
   247   void locked_print_free_chunks(outputStream* st);
   248   void locked_print_sum_free_chunks(outputStream* st);
   250   void print_on(outputStream* st) const;
   251 };
   253 // Used to manage the free list of Metablocks (a block corresponds
   254 // to the allocation of a quantum of metadata).
   255 class BlockFreelist VALUE_OBJ_CLASS_SPEC {
   256   BlockTreeDictionary* _dictionary;
   258   // Only allocate and split from freelist if the size of the allocation
   259   // is at least 1/4th the size of the available block.
   260   const static int WasteMultiplier = 4;
   262   // Accessors
   263   BlockTreeDictionary* dictionary() const { return _dictionary; }
   265  public:
   266   BlockFreelist();
   267   ~BlockFreelist();
   269   // Get and return a block to the free list
   270   MetaWord* get_block(size_t word_size);
   271   void return_block(MetaWord* p, size_t word_size);
   273   size_t total_size() {
   274   if (dictionary() == NULL) {
   275     return 0;
   276   } else {
   277     return dictionary()->total_size();
   278   }
   279 }
   281   void print_on(outputStream* st) const;
   282 };
   284 // A VirtualSpaceList node.
   285 class VirtualSpaceNode : public CHeapObj<mtClass> {
   286   friend class VirtualSpaceList;
   288   // Link to next VirtualSpaceNode
   289   VirtualSpaceNode* _next;
   291   // total in the VirtualSpace
   292   MemRegion _reserved;
   293   ReservedSpace _rs;
   294   VirtualSpace _virtual_space;
   295   MetaWord* _top;
   296   // count of chunks contained in this VirtualSpace
   297   uintx _container_count;
   299   // Convenience functions to access the _virtual_space
   300   char* low()  const { return virtual_space()->low(); }
   301   char* high() const { return virtual_space()->high(); }
   303   // The first Metachunk will be allocated at the bottom of the
   304   // VirtualSpace
   305   Metachunk* first_chunk() { return (Metachunk*) bottom(); }
   307   // Committed but unused space in the virtual space
   308   size_t free_words_in_vs() const;
   309  public:
   311   VirtualSpaceNode(size_t byte_size);
   312   VirtualSpaceNode(ReservedSpace rs) : _top(NULL), _next(NULL), _rs(rs), _container_count(0) {}
   313   ~VirtualSpaceNode();
   315   // Convenience functions for logical bottom and end
   316   MetaWord* bottom() const { return (MetaWord*) _virtual_space.low(); }
   317   MetaWord* end() const { return (MetaWord*) _virtual_space.high(); }
   319   bool contains(const void* ptr) { return ptr >= low() && ptr < high(); }
   321   size_t reserved_words() const  { return _virtual_space.reserved_size() / BytesPerWord; }
   322   size_t committed_words() const { return _virtual_space.actual_committed_size() / BytesPerWord; }
   324   bool is_pre_committed() const { return _virtual_space.special(); }
   326   // address of next available space in _virtual_space;
   327   // Accessors
   328   VirtualSpaceNode* next() { return _next; }
   329   void set_next(VirtualSpaceNode* v) { _next = v; }
   331   void set_reserved(MemRegion const v) { _reserved = v; }
   332   void set_top(MetaWord* v) { _top = v; }
   334   // Accessors
   335   MemRegion* reserved() { return &_reserved; }
   336   VirtualSpace* virtual_space() const { return (VirtualSpace*) &_virtual_space; }
   338   // Returns true if "word_size" is available in the VirtualSpace
   339   bool is_available(size_t word_size) { return word_size <= pointer_delta(end(), _top, sizeof(MetaWord)); }
   341   MetaWord* top() const { return _top; }
   342   void inc_top(size_t word_size) { _top += word_size; }
   344   uintx container_count() { return _container_count; }
   345   void inc_container_count();
   346   void dec_container_count();
   347 #ifdef ASSERT
   348   uint container_count_slow();
   349   void verify_container_count();
   350 #endif
   352   // used and capacity in this single entry in the list
   353   size_t used_words_in_vs() const;
   354   size_t capacity_words_in_vs() const;
   356   bool initialize();
   358   // get space from the virtual space
   359   Metachunk* take_from_committed(size_t chunk_word_size);
   361   // Allocate a chunk from the virtual space and return it.
   362   Metachunk* get_chunk_vs(size_t chunk_word_size);
   364   // Expands/shrinks the committed space in a virtual space.  Delegates
   365   // to Virtualspace
   366   bool expand_by(size_t min_words, size_t preferred_words);
   368   // In preparation for deleting this node, remove all the chunks
   369   // in the node from any freelist.
   370   void purge(ChunkManager* chunk_manager);
   372   // If an allocation doesn't fit in the current node a new node is created.
   373   // Allocate chunks out of the remaining committed space in this node
   374   // to avoid wasting that memory.
   375   // This always adds up because all the chunk sizes are multiples of
   376   // the smallest chunk size.
   377   void retire(ChunkManager* chunk_manager);
   379 #ifdef ASSERT
   380   // Debug support
   381   void mangle();
   382 #endif
   384   void print_on(outputStream* st) const;
   385 };
   387 #define assert_is_ptr_aligned(ptr, alignment) \
   388   assert(is_ptr_aligned(ptr, alignment),      \
   389     err_msg(PTR_FORMAT " is not aligned to "  \
   390       SIZE_FORMAT, ptr, alignment))
   392 #define assert_is_size_aligned(size, alignment) \
   393   assert(is_size_aligned(size, alignment),      \
   394     err_msg(SIZE_FORMAT " is not aligned to "   \
   395        SIZE_FORMAT, size, alignment))
   398 // Decide if large pages should be committed when the memory is reserved.
   399 static bool should_commit_large_pages_when_reserving(size_t bytes) {
   400   if (UseLargePages && UseLargePagesInMetaspace && !os::can_commit_large_page_memory()) {
   401     size_t words = bytes / BytesPerWord;
   402     bool is_class = false; // We never reserve large pages for the class space.
   403     if (MetaspaceGC::can_expand(words, is_class) &&
   404         MetaspaceGC::allowed_expansion() >= words) {
   405       return true;
   406     }
   407   }
   409   return false;
   410 }
   412   // byte_size is the size of the associated virtualspace.
   413 VirtualSpaceNode::VirtualSpaceNode(size_t bytes) : _top(NULL), _next(NULL), _rs(), _container_count(0) {
   414   assert_is_size_aligned(bytes, Metaspace::reserve_alignment());
   416 #if INCLUDE_CDS
   417   // This allocates memory with mmap.  For DumpSharedspaces, try to reserve
   418   // configurable address, generally at the top of the Java heap so other
   419   // memory addresses don't conflict.
   420   if (DumpSharedSpaces) {
   421     bool large_pages = false; // No large pages when dumping the CDS archive.
   422     char* shared_base = (char*)align_ptr_up((char*)SharedBaseAddress, Metaspace::reserve_alignment());
   424     _rs = ReservedSpace(bytes, Metaspace::reserve_alignment(), large_pages, shared_base, 0);
   425     if (_rs.is_reserved()) {
   426       assert(shared_base == 0 || _rs.base() == shared_base, "should match");
   427     } else {
   428       // Get a mmap region anywhere if the SharedBaseAddress fails.
   429       _rs = ReservedSpace(bytes, Metaspace::reserve_alignment(), large_pages);
   430     }
   431     MetaspaceShared::set_shared_rs(&_rs);
   432   } else
   433 #endif
   434   {
   435     bool large_pages = should_commit_large_pages_when_reserving(bytes);
   437     _rs = ReservedSpace(bytes, Metaspace::reserve_alignment(), large_pages);
   438   }
   440   if (_rs.is_reserved()) {
   441     assert(_rs.base() != NULL, "Catch if we get a NULL address");
   442     assert(_rs.size() != 0, "Catch if we get a 0 size");
   443     assert_is_ptr_aligned(_rs.base(), Metaspace::reserve_alignment());
   444     assert_is_size_aligned(_rs.size(), Metaspace::reserve_alignment());
   446     MemTracker::record_virtual_memory_type((address)_rs.base(), mtClass);
   447   }
   448 }
   450 void VirtualSpaceNode::purge(ChunkManager* chunk_manager) {
   451   Metachunk* chunk = first_chunk();
   452   Metachunk* invalid_chunk = (Metachunk*) top();
   453   while (chunk < invalid_chunk ) {
   454     assert(chunk->is_tagged_free(), "Should be tagged free");
   455     MetaWord* next = ((MetaWord*)chunk) + chunk->word_size();
   456     chunk_manager->remove_chunk(chunk);
   457     assert(chunk->next() == NULL &&
   458            chunk->prev() == NULL,
   459            "Was not removed from its list");
   460     chunk = (Metachunk*) next;
   461   }
   462 }
   464 #ifdef ASSERT
   465 uint VirtualSpaceNode::container_count_slow() {
   466   uint count = 0;
   467   Metachunk* chunk = first_chunk();
   468   Metachunk* invalid_chunk = (Metachunk*) top();
   469   while (chunk < invalid_chunk ) {
   470     MetaWord* next = ((MetaWord*)chunk) + chunk->word_size();
   471     // Don't count the chunks on the free lists.  Those are
   472     // still part of the VirtualSpaceNode but not currently
   473     // counted.
   474     if (!chunk->is_tagged_free()) {
   475       count++;
   476     }
   477     chunk = (Metachunk*) next;
   478   }
   479   return count;
   480 }
   481 #endif
   483 // List of VirtualSpaces for metadata allocation.
   484 class VirtualSpaceList : public CHeapObj<mtClass> {
   485   friend class VirtualSpaceNode;
   487   enum VirtualSpaceSizes {
   488     VirtualSpaceSize = 256 * K
   489   };
   491   // Head of the list
   492   VirtualSpaceNode* _virtual_space_list;
   493   // virtual space currently being used for allocations
   494   VirtualSpaceNode* _current_virtual_space;
   496   // Is this VirtualSpaceList used for the compressed class space
   497   bool _is_class;
   499   // Sum of reserved and committed memory in the virtual spaces
   500   size_t _reserved_words;
   501   size_t _committed_words;
   503   // Number of virtual spaces
   504   size_t _virtual_space_count;
   506   ~VirtualSpaceList();
   508   VirtualSpaceNode* virtual_space_list() const { return _virtual_space_list; }
   510   void set_virtual_space_list(VirtualSpaceNode* v) {
   511     _virtual_space_list = v;
   512   }
   513   void set_current_virtual_space(VirtualSpaceNode* v) {
   514     _current_virtual_space = v;
   515   }
   517   void link_vs(VirtualSpaceNode* new_entry);
   519   // Get another virtual space and add it to the list.  This
   520   // is typically prompted by a failed attempt to allocate a chunk
   521   // and is typically followed by the allocation of a chunk.
   522   bool create_new_virtual_space(size_t vs_word_size);
   524   // Chunk up the unused committed space in the current
   525   // virtual space and add the chunks to the free list.
   526   void retire_current_virtual_space();
   528  public:
   529   VirtualSpaceList(size_t word_size);
   530   VirtualSpaceList(ReservedSpace rs);
   532   size_t free_bytes();
   534   Metachunk* get_new_chunk(size_t chunk_word_size,
   535                            size_t suggested_commit_granularity);
   537   bool expand_node_by(VirtualSpaceNode* node,
   538                       size_t min_words,
   539                       size_t preferred_words);
   541   bool expand_by(size_t min_words,
   542                  size_t preferred_words);
   544   VirtualSpaceNode* current_virtual_space() {
   545     return _current_virtual_space;
   546   }
   548   bool is_class() const { return _is_class; }
   550   bool initialization_succeeded() { return _virtual_space_list != NULL; }
   552   size_t reserved_words()  { return _reserved_words; }
   553   size_t reserved_bytes()  { return reserved_words() * BytesPerWord; }
   554   size_t committed_words() { return _committed_words; }
   555   size_t committed_bytes() { return committed_words() * BytesPerWord; }
   557   void inc_reserved_words(size_t v);
   558   void dec_reserved_words(size_t v);
   559   void inc_committed_words(size_t v);
   560   void dec_committed_words(size_t v);
   561   void inc_virtual_space_count();
   562   void dec_virtual_space_count();
   564   bool contains(const void* ptr);
   566   // Unlink empty VirtualSpaceNodes and free it.
   567   void purge(ChunkManager* chunk_manager);
   569   void print_on(outputStream* st) const;
   571   class VirtualSpaceListIterator : public StackObj {
   572     VirtualSpaceNode* _virtual_spaces;
   573    public:
   574     VirtualSpaceListIterator(VirtualSpaceNode* virtual_spaces) :
   575       _virtual_spaces(virtual_spaces) {}
   577     bool repeat() {
   578       return _virtual_spaces != NULL;
   579     }
   581     VirtualSpaceNode* get_next() {
   582       VirtualSpaceNode* result = _virtual_spaces;
   583       if (_virtual_spaces != NULL) {
   584         _virtual_spaces = _virtual_spaces->next();
   585       }
   586       return result;
   587     }
   588   };
   589 };
   591 class Metadebug : AllStatic {
   592   // Debugging support for Metaspaces
   593   static int _allocation_fail_alot_count;
   595  public:
   597   static void init_allocation_fail_alot_count();
   598 #ifdef ASSERT
   599   static bool test_metadata_failure();
   600 #endif
   601 };
   603 int Metadebug::_allocation_fail_alot_count = 0;
   605 //  SpaceManager - used by Metaspace to handle allocations
   606 class SpaceManager : public CHeapObj<mtClass> {
   607   friend class Metaspace;
   608   friend class Metadebug;
   610  private:
   612   // protects allocations
   613   Mutex* const _lock;
   615   // Type of metadata allocated.
   616   Metaspace::MetadataType _mdtype;
   618   // List of chunks in use by this SpaceManager.  Allocations
   619   // are done from the current chunk.  The list is used for deallocating
   620   // chunks when the SpaceManager is freed.
   621   Metachunk* _chunks_in_use[NumberOfInUseLists];
   622   Metachunk* _current_chunk;
   624   // Number of small chunks to allocate to a manager
   625   // If class space manager, small chunks are unlimited
   626   static uint const _small_chunk_limit;
   628   // Sum of all space in allocated chunks
   629   size_t _allocated_blocks_words;
   631   // Sum of all allocated chunks
   632   size_t _allocated_chunks_words;
   633   size_t _allocated_chunks_count;
   635   // Free lists of blocks are per SpaceManager since they
   636   // are assumed to be in chunks in use by the SpaceManager
   637   // and all chunks in use by a SpaceManager are freed when
   638   // the class loader using the SpaceManager is collected.
   639   BlockFreelist _block_freelists;
   641   // protects virtualspace and chunk expansions
   642   static const char*  _expand_lock_name;
   643   static const int    _expand_lock_rank;
   644   static Mutex* const _expand_lock;
   646  private:
   647   // Accessors
   648   Metachunk* chunks_in_use(ChunkIndex index) const { return _chunks_in_use[index]; }
   649   void set_chunks_in_use(ChunkIndex index, Metachunk* v) {
   650     _chunks_in_use[index] = v;
   651   }
   653   BlockFreelist* block_freelists() const {
   654     return (BlockFreelist*) &_block_freelists;
   655   }
   657   Metaspace::MetadataType mdtype() { return _mdtype; }
   659   VirtualSpaceList* vs_list()   const { return Metaspace::get_space_list(_mdtype); }
   660   ChunkManager* chunk_manager() const { return Metaspace::get_chunk_manager(_mdtype); }
   662   Metachunk* current_chunk() const { return _current_chunk; }
   663   void set_current_chunk(Metachunk* v) {
   664     _current_chunk = v;
   665   }
   667   Metachunk* find_current_chunk(size_t word_size);
   669   // Add chunk to the list of chunks in use
   670   void add_chunk(Metachunk* v, bool make_current);
   671   void retire_current_chunk();
   673   Mutex* lock() const { return _lock; }
   675   const char* chunk_size_name(ChunkIndex index) const;
   677  protected:
   678   void initialize();
   680  public:
   681   SpaceManager(Metaspace::MetadataType mdtype,
   682                Mutex* lock);
   683   ~SpaceManager();
   685   enum ChunkMultiples {
   686     MediumChunkMultiple = 4
   687   };
   689   static size_t specialized_chunk_size(bool is_class) { return is_class ? ClassSpecializedChunk : SpecializedChunk; }
   690   static size_t small_chunk_size(bool is_class)       { return is_class ? ClassSmallChunk : SmallChunk; }
   691   static size_t medium_chunk_size(bool is_class)      { return is_class ? ClassMediumChunk : MediumChunk; }
   693   static size_t smallest_chunk_size(bool is_class)    { return specialized_chunk_size(is_class); }
   695   // Accessors
   696   bool is_class() const { return _mdtype == Metaspace::ClassType; }
   698   size_t specialized_chunk_size() const { return specialized_chunk_size(is_class()); }
   699   size_t small_chunk_size()       const { return small_chunk_size(is_class()); }
   700   size_t medium_chunk_size()      const { return medium_chunk_size(is_class()); }
   702   size_t smallest_chunk_size()    const { return smallest_chunk_size(is_class()); }
   704   size_t medium_chunk_bunch()     const { return medium_chunk_size() * MediumChunkMultiple; }
   706   size_t allocated_blocks_words() const { return _allocated_blocks_words; }
   707   size_t allocated_blocks_bytes() const { return _allocated_blocks_words * BytesPerWord; }
   708   size_t allocated_chunks_words() const { return _allocated_chunks_words; }
   709   size_t allocated_chunks_bytes() const { return _allocated_chunks_words * BytesPerWord; }
   710   size_t allocated_chunks_count() const { return _allocated_chunks_count; }
   712   bool is_humongous(size_t word_size) { return word_size > medium_chunk_size(); }
   714   static Mutex* expand_lock() { return _expand_lock; }
   716   // Increment the per Metaspace and global running sums for Metachunks
   717   // by the given size.  This is used when a Metachunk to added to
   718   // the in-use list.
   719   void inc_size_metrics(size_t words);
   720   // Increment the per Metaspace and global running sums Metablocks by the given
   721   // size.  This is used when a Metablock is allocated.
   722   void inc_used_metrics(size_t words);
   723   // Delete the portion of the running sums for this SpaceManager. That is,
   724   // the globals running sums for the Metachunks and Metablocks are
   725   // decremented for all the Metachunks in-use by this SpaceManager.
   726   void dec_total_from_size_metrics();
   728   // Adjust the initial chunk size to match one of the fixed chunk list sizes,
   729   // or return the unadjusted size if the requested size is humongous.
   730   static size_t adjust_initial_chunk_size(size_t requested, bool is_class_space);
   731   size_t adjust_initial_chunk_size(size_t requested) const;
   733   // Get the initial chunks size for this metaspace type.
   734   size_t get_initial_chunk_size(Metaspace::MetaspaceType type) const;
   736   size_t sum_capacity_in_chunks_in_use() const;
   737   size_t sum_used_in_chunks_in_use() const;
   738   size_t sum_free_in_chunks_in_use() const;
   739   size_t sum_waste_in_chunks_in_use() const;
   740   size_t sum_waste_in_chunks_in_use(ChunkIndex index ) const;
   742   size_t sum_count_in_chunks_in_use();
   743   size_t sum_count_in_chunks_in_use(ChunkIndex i);
   745   Metachunk* get_new_chunk(size_t chunk_word_size);
   747   // Block allocation and deallocation.
   748   // Allocates a block from the current chunk
   749   MetaWord* allocate(size_t word_size);
   751   // Helper for allocations
   752   MetaWord* allocate_work(size_t word_size);
   754   // Returns a block to the per manager freelist
   755   void deallocate(MetaWord* p, size_t word_size);
   757   // Based on the allocation size and a minimum chunk size,
   758   // returned chunk size (for expanding space for chunk allocation).
   759   size_t calc_chunk_size(size_t allocation_word_size);
   761   // Called when an allocation from the current chunk fails.
   762   // Gets a new chunk (may require getting a new virtual space),
   763   // and allocates from that chunk.
   764   MetaWord* grow_and_allocate(size_t word_size);
   766   // Notify memory usage to MemoryService.
   767   void track_metaspace_memory_usage();
   769   // debugging support.
   771   void dump(outputStream* const out) const;
   772   void print_on(outputStream* st) const;
   773   void locked_print_chunks_in_use_on(outputStream* st) const;
   775   void verify();
   776   void verify_chunk_size(Metachunk* chunk);
   777   NOT_PRODUCT(void mangle_freed_chunks();)
   778 #ifdef ASSERT
   779   void verify_allocated_blocks_words();
   780 #endif
   782   size_t get_raw_word_size(size_t word_size) {
   783     size_t byte_size = word_size * BytesPerWord;
   785     size_t raw_bytes_size = MAX2(byte_size, sizeof(Metablock));
   786     raw_bytes_size = align_size_up(raw_bytes_size, Metachunk::object_alignment());
   788     size_t raw_word_size = raw_bytes_size / BytesPerWord;
   789     assert(raw_word_size * BytesPerWord == raw_bytes_size, "Size problem");
   791     return raw_word_size;
   792   }
   793 };
   795 uint const SpaceManager::_small_chunk_limit = 4;
   797 const char* SpaceManager::_expand_lock_name =
   798   "SpaceManager chunk allocation lock";
   799 const int SpaceManager::_expand_lock_rank = Monitor::leaf - 1;
   800 Mutex* const SpaceManager::_expand_lock =
   801   new Mutex(SpaceManager::_expand_lock_rank,
   802             SpaceManager::_expand_lock_name,
   803             Mutex::_allow_vm_block_flag);
   805 void VirtualSpaceNode::inc_container_count() {
   806   assert_lock_strong(SpaceManager::expand_lock());
   807   _container_count++;
   808   assert(_container_count == container_count_slow(),
   809          err_msg("Inconsistency in countainer_count _container_count " SIZE_FORMAT
   810                  " container_count_slow() " SIZE_FORMAT,
   811                  _container_count, container_count_slow()));
   812 }
   814 void VirtualSpaceNode::dec_container_count() {
   815   assert_lock_strong(SpaceManager::expand_lock());
   816   _container_count--;
   817 }
   819 #ifdef ASSERT
   820 void VirtualSpaceNode::verify_container_count() {
   821   assert(_container_count == container_count_slow(),
   822     err_msg("Inconsistency in countainer_count _container_count " SIZE_FORMAT
   823             " container_count_slow() " SIZE_FORMAT, _container_count, container_count_slow()));
   824 }
   825 #endif
   827 // BlockFreelist methods
   829 BlockFreelist::BlockFreelist() : _dictionary(NULL) {}
   831 BlockFreelist::~BlockFreelist() {
   832   if (_dictionary != NULL) {
   833     if (Verbose && TraceMetadataChunkAllocation) {
   834       _dictionary->print_free_lists(gclog_or_tty);
   835     }
   836     delete _dictionary;
   837   }
   838 }
   840 void BlockFreelist::return_block(MetaWord* p, size_t word_size) {
   841   Metablock* free_chunk = ::new (p) Metablock(word_size);
   842   if (dictionary() == NULL) {
   843    _dictionary = new BlockTreeDictionary();
   844   }
   845   dictionary()->return_chunk(free_chunk);
   846 }
   848 MetaWord* BlockFreelist::get_block(size_t word_size) {
   849   if (dictionary() == NULL) {
   850     return NULL;
   851   }
   853   if (word_size < TreeChunk<Metablock, FreeList<Metablock> >::min_size()) {
   854     // Dark matter.  Too small for dictionary.
   855     return NULL;
   856   }
   858   Metablock* free_block =
   859     dictionary()->get_chunk(word_size, FreeBlockDictionary<Metablock>::atLeast);
   860   if (free_block == NULL) {
   861     return NULL;
   862   }
   864   const size_t block_size = free_block->size();
   865   if (block_size > WasteMultiplier * word_size) {
   866     return_block((MetaWord*)free_block, block_size);
   867     return NULL;
   868   }
   870   MetaWord* new_block = (MetaWord*)free_block;
   871   assert(block_size >= word_size, "Incorrect size of block from freelist");
   872   const size_t unused = block_size - word_size;
   873   if (unused >= TreeChunk<Metablock, FreeList<Metablock> >::min_size()) {
   874     return_block(new_block + word_size, unused);
   875   }
   877   return new_block;
   878 }
   880 void BlockFreelist::print_on(outputStream* st) const {
   881   if (dictionary() == NULL) {
   882     return;
   883   }
   884   dictionary()->print_free_lists(st);
   885 }
   887 // VirtualSpaceNode methods
   889 VirtualSpaceNode::~VirtualSpaceNode() {
   890   _rs.release();
   891 #ifdef ASSERT
   892   size_t word_size = sizeof(*this) / BytesPerWord;
   893   Copy::fill_to_words((HeapWord*) this, word_size, 0xf1f1f1f1);
   894 #endif
   895 }
   897 size_t VirtualSpaceNode::used_words_in_vs() const {
   898   return pointer_delta(top(), bottom(), sizeof(MetaWord));
   899 }
   901 // Space committed in the VirtualSpace
   902 size_t VirtualSpaceNode::capacity_words_in_vs() const {
   903   return pointer_delta(end(), bottom(), sizeof(MetaWord));
   904 }
   906 size_t VirtualSpaceNode::free_words_in_vs() const {
   907   return pointer_delta(end(), top(), sizeof(MetaWord));
   908 }
   910 // Allocates the chunk from the virtual space only.
   911 // This interface is also used internally for debugging.  Not all
   912 // chunks removed here are necessarily used for allocation.
   913 Metachunk* VirtualSpaceNode::take_from_committed(size_t chunk_word_size) {
   914   // Bottom of the new chunk
   915   MetaWord* chunk_limit = top();
   916   assert(chunk_limit != NULL, "Not safe to call this method");
   918   // The virtual spaces are always expanded by the
   919   // commit granularity to enforce the following condition.
   920   // Without this the is_available check will not work correctly.
   921   assert(_virtual_space.committed_size() == _virtual_space.actual_committed_size(),
   922       "The committed memory doesn't match the expanded memory.");
   924   if (!is_available(chunk_word_size)) {
   925     if (TraceMetadataChunkAllocation) {
   926       gclog_or_tty->print("VirtualSpaceNode::take_from_committed() not available %d words ", chunk_word_size);
   927       // Dump some information about the virtual space that is nearly full
   928       print_on(gclog_or_tty);
   929     }
   930     return NULL;
   931   }
   933   // Take the space  (bump top on the current virtual space).
   934   inc_top(chunk_word_size);
   936   // Initialize the chunk
   937   Metachunk* result = ::new (chunk_limit) Metachunk(chunk_word_size, this);
   938   return result;
   939 }
   942 // Expand the virtual space (commit more of the reserved space)
   943 bool VirtualSpaceNode::expand_by(size_t min_words, size_t preferred_words) {
   944   size_t min_bytes = min_words * BytesPerWord;
   945   size_t preferred_bytes = preferred_words * BytesPerWord;
   947   size_t uncommitted = virtual_space()->reserved_size() - virtual_space()->actual_committed_size();
   949   if (uncommitted < min_bytes) {
   950     return false;
   951   }
   953   size_t commit = MIN2(preferred_bytes, uncommitted);
   954   bool result = virtual_space()->expand_by(commit, false);
   956   assert(result, "Failed to commit memory");
   958   return result;
   959 }
   961 Metachunk* VirtualSpaceNode::get_chunk_vs(size_t chunk_word_size) {
   962   assert_lock_strong(SpaceManager::expand_lock());
   963   Metachunk* result = take_from_committed(chunk_word_size);
   964   if (result != NULL) {
   965     inc_container_count();
   966   }
   967   return result;
   968 }
   970 bool VirtualSpaceNode::initialize() {
   972   if (!_rs.is_reserved()) {
   973     return false;
   974   }
   976   // These are necessary restriction to make sure that the virtual space always
   977   // grows in steps of Metaspace::commit_alignment(). If both base and size are
   978   // aligned only the middle alignment of the VirtualSpace is used.
   979   assert_is_ptr_aligned(_rs.base(), Metaspace::commit_alignment());
   980   assert_is_size_aligned(_rs.size(), Metaspace::commit_alignment());
   982   // ReservedSpaces marked as special will have the entire memory
   983   // pre-committed. Setting a committed size will make sure that
   984   // committed_size and actual_committed_size agrees.
   985   size_t pre_committed_size = _rs.special() ? _rs.size() : 0;
   987   bool result = virtual_space()->initialize_with_granularity(_rs, pre_committed_size,
   988                                             Metaspace::commit_alignment());
   989   if (result) {
   990     assert(virtual_space()->committed_size() == virtual_space()->actual_committed_size(),
   991         "Checking that the pre-committed memory was registered by the VirtualSpace");
   993     set_top((MetaWord*)virtual_space()->low());
   994     set_reserved(MemRegion((HeapWord*)_rs.base(),
   995                  (HeapWord*)(_rs.base() + _rs.size())));
   997     assert(reserved()->start() == (HeapWord*) _rs.base(),
   998       err_msg("Reserved start was not set properly " PTR_FORMAT
   999         " != " PTR_FORMAT, reserved()->start(), _rs.base()));
  1000     assert(reserved()->word_size() == _rs.size() / BytesPerWord,
  1001       err_msg("Reserved size was not set properly " SIZE_FORMAT
  1002         " != " SIZE_FORMAT, reserved()->word_size(),
  1003         _rs.size() / BytesPerWord));
  1006   return result;
  1009 void VirtualSpaceNode::print_on(outputStream* st) const {
  1010   size_t used = used_words_in_vs();
  1011   size_t capacity = capacity_words_in_vs();
  1012   VirtualSpace* vs = virtual_space();
  1013   st->print_cr("   space @ " PTR_FORMAT " " SIZE_FORMAT "K, %3d%% used "
  1014            "[" PTR_FORMAT ", " PTR_FORMAT ", "
  1015            PTR_FORMAT ", " PTR_FORMAT ")",
  1016            vs, capacity / K,
  1017            capacity == 0 ? 0 : used * 100 / capacity,
  1018            bottom(), top(), end(),
  1019            vs->high_boundary());
  1022 #ifdef ASSERT
  1023 void VirtualSpaceNode::mangle() {
  1024   size_t word_size = capacity_words_in_vs();
  1025   Copy::fill_to_words((HeapWord*) low(), word_size, 0xf1f1f1f1);
  1027 #endif // ASSERT
  1029 // VirtualSpaceList methods
  1030 // Space allocated from the VirtualSpace
  1032 VirtualSpaceList::~VirtualSpaceList() {
  1033   VirtualSpaceListIterator iter(virtual_space_list());
  1034   while (iter.repeat()) {
  1035     VirtualSpaceNode* vsl = iter.get_next();
  1036     delete vsl;
  1040 void VirtualSpaceList::inc_reserved_words(size_t v) {
  1041   assert_lock_strong(SpaceManager::expand_lock());
  1042   _reserved_words = _reserved_words + v;
  1044 void VirtualSpaceList::dec_reserved_words(size_t v) {
  1045   assert_lock_strong(SpaceManager::expand_lock());
  1046   _reserved_words = _reserved_words - v;
  1049 #define assert_committed_below_limit()                             \
  1050   assert(MetaspaceAux::committed_bytes() <= MaxMetaspaceSize,      \
  1051       err_msg("Too much committed memory. Committed: " SIZE_FORMAT \
  1052               " limit (MaxMetaspaceSize): " SIZE_FORMAT,           \
  1053           MetaspaceAux::committed_bytes(), MaxMetaspaceSize));
  1055 void VirtualSpaceList::inc_committed_words(size_t v) {
  1056   assert_lock_strong(SpaceManager::expand_lock());
  1057   _committed_words = _committed_words + v;
  1059   assert_committed_below_limit();
  1061 void VirtualSpaceList::dec_committed_words(size_t v) {
  1062   assert_lock_strong(SpaceManager::expand_lock());
  1063   _committed_words = _committed_words - v;
  1065   assert_committed_below_limit();
  1068 void VirtualSpaceList::inc_virtual_space_count() {
  1069   assert_lock_strong(SpaceManager::expand_lock());
  1070   _virtual_space_count++;
  1072 void VirtualSpaceList::dec_virtual_space_count() {
  1073   assert_lock_strong(SpaceManager::expand_lock());
  1074   _virtual_space_count--;
  1077 void ChunkManager::remove_chunk(Metachunk* chunk) {
  1078   size_t word_size = chunk->word_size();
  1079   ChunkIndex index = list_index(word_size);
  1080   if (index != HumongousIndex) {
  1081     free_chunks(index)->remove_chunk(chunk);
  1082   } else {
  1083     humongous_dictionary()->remove_chunk(chunk);
  1086   // Chunk is being removed from the chunks free list.
  1087   dec_free_chunks_total(chunk->word_size());
  1090 // Walk the list of VirtualSpaceNodes and delete
  1091 // nodes with a 0 container_count.  Remove Metachunks in
  1092 // the node from their respective freelists.
  1093 void VirtualSpaceList::purge(ChunkManager* chunk_manager) {
  1094   assert(SafepointSynchronize::is_at_safepoint(), "must be called at safepoint for contains to work");
  1095   assert_lock_strong(SpaceManager::expand_lock());
  1096   // Don't use a VirtualSpaceListIterator because this
  1097   // list is being changed and a straightforward use of an iterator is not safe.
  1098   VirtualSpaceNode* purged_vsl = NULL;
  1099   VirtualSpaceNode* prev_vsl = virtual_space_list();
  1100   VirtualSpaceNode* next_vsl = prev_vsl;
  1101   while (next_vsl != NULL) {
  1102     VirtualSpaceNode* vsl = next_vsl;
  1103     next_vsl = vsl->next();
  1104     // Don't free the current virtual space since it will likely
  1105     // be needed soon.
  1106     if (vsl->container_count() == 0 && vsl != current_virtual_space()) {
  1107       // Unlink it from the list
  1108       if (prev_vsl == vsl) {
  1109         // This is the case of the current node being the first node.
  1110         assert(vsl == virtual_space_list(), "Expected to be the first node");
  1111         set_virtual_space_list(vsl->next());
  1112       } else {
  1113         prev_vsl->set_next(vsl->next());
  1116       vsl->purge(chunk_manager);
  1117       dec_reserved_words(vsl->reserved_words());
  1118       dec_committed_words(vsl->committed_words());
  1119       dec_virtual_space_count();
  1120       purged_vsl = vsl;
  1121       delete vsl;
  1122     } else {
  1123       prev_vsl = vsl;
  1126 #ifdef ASSERT
  1127   if (purged_vsl != NULL) {
  1128     // List should be stable enough to use an iterator here.
  1129     VirtualSpaceListIterator iter(virtual_space_list());
  1130     while (iter.repeat()) {
  1131       VirtualSpaceNode* vsl = iter.get_next();
  1132       assert(vsl != purged_vsl, "Purge of vsl failed");
  1135 #endif
  1139 // This function looks at the mmap regions in the metaspace without locking.
  1140 // The chunks are added with store ordering and not deleted except for at
  1141 // unloading time during a safepoint.
  1142 bool VirtualSpaceList::contains(const void* ptr) {
  1143   // List should be stable enough to use an iterator here because removing virtual
  1144   // space nodes is only allowed at a safepoint.
  1145   VirtualSpaceListIterator iter(virtual_space_list());
  1146   while (iter.repeat()) {
  1147     VirtualSpaceNode* vsn = iter.get_next();
  1148     if (vsn->contains(ptr)) {
  1149       return true;
  1152   return false;
  1155 void VirtualSpaceList::retire_current_virtual_space() {
  1156   assert_lock_strong(SpaceManager::expand_lock());
  1158   VirtualSpaceNode* vsn = current_virtual_space();
  1160   ChunkManager* cm = is_class() ? Metaspace::chunk_manager_class() :
  1161                                   Metaspace::chunk_manager_metadata();
  1163   vsn->retire(cm);
  1166 void VirtualSpaceNode::retire(ChunkManager* chunk_manager) {
  1167   for (int i = (int)MediumIndex; i >= (int)ZeroIndex; --i) {
  1168     ChunkIndex index = (ChunkIndex)i;
  1169     size_t chunk_size = chunk_manager->free_chunks(index)->size();
  1171     while (free_words_in_vs() >= chunk_size) {
  1172       DEBUG_ONLY(verify_container_count();)
  1173       Metachunk* chunk = get_chunk_vs(chunk_size);
  1174       assert(chunk != NULL, "allocation should have been successful");
  1176       chunk_manager->return_chunks(index, chunk);
  1177       chunk_manager->inc_free_chunks_total(chunk_size);
  1178       DEBUG_ONLY(verify_container_count();)
  1181   assert(free_words_in_vs() == 0, "should be empty now");
  1184 VirtualSpaceList::VirtualSpaceList(size_t word_size) :
  1185                                    _is_class(false),
  1186                                    _virtual_space_list(NULL),
  1187                                    _current_virtual_space(NULL),
  1188                                    _reserved_words(0),
  1189                                    _committed_words(0),
  1190                                    _virtual_space_count(0) {
  1191   MutexLockerEx cl(SpaceManager::expand_lock(),
  1192                    Mutex::_no_safepoint_check_flag);
  1193   create_new_virtual_space(word_size);
  1196 VirtualSpaceList::VirtualSpaceList(ReservedSpace rs) :
  1197                                    _is_class(true),
  1198                                    _virtual_space_list(NULL),
  1199                                    _current_virtual_space(NULL),
  1200                                    _reserved_words(0),
  1201                                    _committed_words(0),
  1202                                    _virtual_space_count(0) {
  1203   MutexLockerEx cl(SpaceManager::expand_lock(),
  1204                    Mutex::_no_safepoint_check_flag);
  1205   VirtualSpaceNode* class_entry = new VirtualSpaceNode(rs);
  1206   bool succeeded = class_entry->initialize();
  1207   if (succeeded) {
  1208     link_vs(class_entry);
  1212 size_t VirtualSpaceList::free_bytes() {
  1213   return current_virtual_space()->free_words_in_vs() * BytesPerWord;
  1216 // Allocate another meta virtual space and add it to the list.
  1217 bool VirtualSpaceList::create_new_virtual_space(size_t vs_word_size) {
  1218   assert_lock_strong(SpaceManager::expand_lock());
  1220   if (is_class()) {
  1221     assert(false, "We currently don't support more than one VirtualSpace for"
  1222                   " the compressed class space. The initialization of the"
  1223                   " CCS uses another code path and should not hit this path.");
  1224     return false;
  1227   if (vs_word_size == 0) {
  1228     assert(false, "vs_word_size should always be at least _reserve_alignment large.");
  1229     return false;
  1232   // Reserve the space
  1233   size_t vs_byte_size = vs_word_size * BytesPerWord;
  1234   assert_is_size_aligned(vs_byte_size, Metaspace::reserve_alignment());
  1236   // Allocate the meta virtual space and initialize it.
  1237   VirtualSpaceNode* new_entry = new VirtualSpaceNode(vs_byte_size);
  1238   if (!new_entry->initialize()) {
  1239     delete new_entry;
  1240     return false;
  1241   } else {
  1242     assert(new_entry->reserved_words() == vs_word_size,
  1243         "Reserved memory size differs from requested memory size");
  1244     // ensure lock-free iteration sees fully initialized node
  1245     OrderAccess::storestore();
  1246     link_vs(new_entry);
  1247     return true;
  1251 void VirtualSpaceList::link_vs(VirtualSpaceNode* new_entry) {
  1252   if (virtual_space_list() == NULL) {
  1253       set_virtual_space_list(new_entry);
  1254   } else {
  1255     current_virtual_space()->set_next(new_entry);
  1257   set_current_virtual_space(new_entry);
  1258   inc_reserved_words(new_entry->reserved_words());
  1259   inc_committed_words(new_entry->committed_words());
  1260   inc_virtual_space_count();
  1261 #ifdef ASSERT
  1262   new_entry->mangle();
  1263 #endif
  1264   if (TraceMetavirtualspaceAllocation && Verbose) {
  1265     VirtualSpaceNode* vsl = current_virtual_space();
  1266     vsl->print_on(gclog_or_tty);
  1270 bool VirtualSpaceList::expand_node_by(VirtualSpaceNode* node,
  1271                                       size_t min_words,
  1272                                       size_t preferred_words) {
  1273   size_t before = node->committed_words();
  1275   bool result = node->expand_by(min_words, preferred_words);
  1277   size_t after = node->committed_words();
  1279   // after and before can be the same if the memory was pre-committed.
  1280   assert(after >= before, "Inconsistency");
  1281   inc_committed_words(after - before);
  1283   return result;
  1286 bool VirtualSpaceList::expand_by(size_t min_words, size_t preferred_words) {
  1287   assert_is_size_aligned(min_words,       Metaspace::commit_alignment_words());
  1288   assert_is_size_aligned(preferred_words, Metaspace::commit_alignment_words());
  1289   assert(min_words <= preferred_words, "Invalid arguments");
  1291   if (!MetaspaceGC::can_expand(min_words, this->is_class())) {
  1292     return  false;
  1295   size_t allowed_expansion_words = MetaspaceGC::allowed_expansion();
  1296   if (allowed_expansion_words < min_words) {
  1297     return false;
  1300   size_t max_expansion_words = MIN2(preferred_words, allowed_expansion_words);
  1302   // Commit more memory from the the current virtual space.
  1303   bool vs_expanded = expand_node_by(current_virtual_space(),
  1304                                     min_words,
  1305                                     max_expansion_words);
  1306   if (vs_expanded) {
  1307     return true;
  1309   retire_current_virtual_space();
  1311   // Get another virtual space.
  1312   size_t grow_vs_words = MAX2((size_t)VirtualSpaceSize, preferred_words);
  1313   grow_vs_words = align_size_up(grow_vs_words, Metaspace::reserve_alignment_words());
  1315   if (create_new_virtual_space(grow_vs_words)) {
  1316     if (current_virtual_space()->is_pre_committed()) {
  1317       // The memory was pre-committed, so we are done here.
  1318       assert(min_words <= current_virtual_space()->committed_words(),
  1319           "The new VirtualSpace was pre-committed, so it"
  1320           "should be large enough to fit the alloc request.");
  1321       return true;
  1324     return expand_node_by(current_virtual_space(),
  1325                           min_words,
  1326                           max_expansion_words);
  1329   return false;
  1332 Metachunk* VirtualSpaceList::get_new_chunk(size_t chunk_word_size, size_t suggested_commit_granularity) {
  1334   // Allocate a chunk out of the current virtual space.
  1335   Metachunk* next = current_virtual_space()->get_chunk_vs(chunk_word_size);
  1337   if (next != NULL) {
  1338     return next;
  1341   // The expand amount is currently only determined by the requested sizes
  1342   // and not how much committed memory is left in the current virtual space.
  1344   size_t min_word_size       = align_size_up(chunk_word_size,              Metaspace::commit_alignment_words());
  1345   size_t preferred_word_size = align_size_up(suggested_commit_granularity, Metaspace::commit_alignment_words());
  1346   if (min_word_size >= preferred_word_size) {
  1347     // Can happen when humongous chunks are allocated.
  1348     preferred_word_size = min_word_size;
  1351   bool expanded = expand_by(min_word_size, preferred_word_size);
  1352   if (expanded) {
  1353     next = current_virtual_space()->get_chunk_vs(chunk_word_size);
  1354     assert(next != NULL, "The allocation was expected to succeed after the expansion");
  1357    return next;
  1360 void VirtualSpaceList::print_on(outputStream* st) const {
  1361   if (TraceMetadataChunkAllocation && Verbose) {
  1362     VirtualSpaceListIterator iter(virtual_space_list());
  1363     while (iter.repeat()) {
  1364       VirtualSpaceNode* node = iter.get_next();
  1365       node->print_on(st);
  1370 // MetaspaceGC methods
  1372 // VM_CollectForMetadataAllocation is the vm operation used to GC.
  1373 // Within the VM operation after the GC the attempt to allocate the metadata
  1374 // should succeed.  If the GC did not free enough space for the metaspace
  1375 // allocation, the HWM is increased so that another virtualspace will be
  1376 // allocated for the metadata.  With perm gen the increase in the perm
  1377 // gen had bounds, MinMetaspaceExpansion and MaxMetaspaceExpansion.  The
  1378 // metaspace policy uses those as the small and large steps for the HWM.
  1379 //
  1380 // After the GC the compute_new_size() for MetaspaceGC is called to
  1381 // resize the capacity of the metaspaces.  The current implementation
  1382 // is based on the flags MinMetaspaceFreeRatio and MaxMetaspaceFreeRatio used
  1383 // to resize the Java heap by some GC's.  New flags can be implemented
  1384 // if really needed.  MinMetaspaceFreeRatio is used to calculate how much
  1385 // free space is desirable in the metaspace capacity to decide how much
  1386 // to increase the HWM.  MaxMetaspaceFreeRatio is used to decide how much
  1387 // free space is desirable in the metaspace capacity before decreasing
  1388 // the HWM.
  1390 // Calculate the amount to increase the high water mark (HWM).
  1391 // Increase by a minimum amount (MinMetaspaceExpansion) so that
  1392 // another expansion is not requested too soon.  If that is not
  1393 // enough to satisfy the allocation, increase by MaxMetaspaceExpansion.
  1394 // If that is still not enough, expand by the size of the allocation
  1395 // plus some.
  1396 size_t MetaspaceGC::delta_capacity_until_GC(size_t bytes) {
  1397   size_t min_delta = MinMetaspaceExpansion;
  1398   size_t max_delta = MaxMetaspaceExpansion;
  1399   size_t delta = align_size_up(bytes, Metaspace::commit_alignment());
  1401   if (delta <= min_delta) {
  1402     delta = min_delta;
  1403   } else if (delta <= max_delta) {
  1404     // Don't want to hit the high water mark on the next
  1405     // allocation so make the delta greater than just enough
  1406     // for this allocation.
  1407     delta = max_delta;
  1408   } else {
  1409     // This allocation is large but the next ones are probably not
  1410     // so increase by the minimum.
  1411     delta = delta + min_delta;
  1414   assert_is_size_aligned(delta, Metaspace::commit_alignment());
  1416   return delta;
  1419 size_t MetaspaceGC::capacity_until_GC() {
  1420   size_t value = (size_t)OrderAccess::load_ptr_acquire(&_capacity_until_GC);
  1421   assert(value >= MetaspaceSize, "Not initialied properly?");
  1422   return value;
  1425 bool MetaspaceGC::inc_capacity_until_GC(size_t v, size_t* new_cap_until_GC, size_t* old_cap_until_GC) {
  1426   assert_is_size_aligned(v, Metaspace::commit_alignment());
  1428   size_t capacity_until_GC = (size_t) _capacity_until_GC;
  1429   size_t new_value = capacity_until_GC + v;
  1431   if (new_value < capacity_until_GC) {
  1432     // The addition wrapped around, set new_value to aligned max value.
  1433     new_value = align_size_down(max_uintx, Metaspace::commit_alignment());
  1436   intptr_t expected = (intptr_t) capacity_until_GC;
  1437   intptr_t actual = Atomic::cmpxchg_ptr((intptr_t) new_value, &_capacity_until_GC, expected);
  1439   if (expected != actual) {
  1440     return false;
  1443   if (new_cap_until_GC != NULL) {
  1444     *new_cap_until_GC = new_value;
  1446   if (old_cap_until_GC != NULL) {
  1447     *old_cap_until_GC = capacity_until_GC;
  1449   return true;
  1452 size_t MetaspaceGC::dec_capacity_until_GC(size_t v) {
  1453   assert_is_size_aligned(v, Metaspace::commit_alignment());
  1455   return (size_t)Atomic::add_ptr(-(intptr_t)v, &_capacity_until_GC);
  1458 void MetaspaceGC::initialize() {
  1459   // Set the high-water mark to MaxMetapaceSize during VM initializaton since
  1460   // we can't do a GC during initialization.
  1461   _capacity_until_GC = MaxMetaspaceSize;
  1464 void MetaspaceGC::post_initialize() {
  1465   // Reset the high-water mark once the VM initialization is done.
  1466   _capacity_until_GC = MAX2(MetaspaceAux::committed_bytes(), MetaspaceSize);
  1469 bool MetaspaceGC::can_expand(size_t word_size, bool is_class) {
  1470   // Check if the compressed class space is full.
  1471   if (is_class && Metaspace::using_class_space()) {
  1472     size_t class_committed = MetaspaceAux::committed_bytes(Metaspace::ClassType);
  1473     if (class_committed + word_size * BytesPerWord > CompressedClassSpaceSize) {
  1474       return false;
  1478   // Check if the user has imposed a limit on the metaspace memory.
  1479   size_t committed_bytes = MetaspaceAux::committed_bytes();
  1480   if (committed_bytes + word_size * BytesPerWord > MaxMetaspaceSize) {
  1481     return false;
  1484   return true;
  1487 size_t MetaspaceGC::allowed_expansion() {
  1488   size_t committed_bytes = MetaspaceAux::committed_bytes();
  1489   size_t capacity_until_gc = capacity_until_GC();
  1491   assert(capacity_until_gc >= committed_bytes,
  1492         err_msg("capacity_until_gc: " SIZE_FORMAT " < committed_bytes: " SIZE_FORMAT,
  1493                 capacity_until_gc, committed_bytes));
  1495   size_t left_until_max  = MaxMetaspaceSize - committed_bytes;
  1496   size_t left_until_GC = capacity_until_gc - committed_bytes;
  1497   size_t left_to_commit = MIN2(left_until_GC, left_until_max);
  1499   return left_to_commit / BytesPerWord;
  1502 void MetaspaceGC::compute_new_size() {
  1503   assert(_shrink_factor <= 100, "invalid shrink factor");
  1504   uint current_shrink_factor = _shrink_factor;
  1505   _shrink_factor = 0;
  1507   // Using committed_bytes() for used_after_gc is an overestimation, since the
  1508   // chunk free lists are included in committed_bytes() and the memory in an
  1509   // un-fragmented chunk free list is available for future allocations.
  1510   // However, if the chunk free lists becomes fragmented, then the memory may
  1511   // not be available for future allocations and the memory is therefore "in use".
  1512   // Including the chunk free lists in the definition of "in use" is therefore
  1513   // necessary. Not including the chunk free lists can cause capacity_until_GC to
  1514   // shrink below committed_bytes() and this has caused serious bugs in the past.
  1515   const size_t used_after_gc = MetaspaceAux::committed_bytes();
  1516   const size_t capacity_until_GC = MetaspaceGC::capacity_until_GC();
  1518   const double minimum_free_percentage = MinMetaspaceFreeRatio / 100.0;
  1519   const double maximum_used_percentage = 1.0 - minimum_free_percentage;
  1521   const double min_tmp = used_after_gc / maximum_used_percentage;
  1522   size_t minimum_desired_capacity =
  1523     (size_t)MIN2(min_tmp, double(max_uintx));
  1524   // Don't shrink less than the initial generation size
  1525   minimum_desired_capacity = MAX2(minimum_desired_capacity,
  1526                                   MetaspaceSize);
  1528   if (PrintGCDetails && Verbose) {
  1529     gclog_or_tty->print_cr("\nMetaspaceGC::compute_new_size: ");
  1530     gclog_or_tty->print_cr("  "
  1531                   "  minimum_free_percentage: %6.2f"
  1532                   "  maximum_used_percentage: %6.2f",
  1533                   minimum_free_percentage,
  1534                   maximum_used_percentage);
  1535     gclog_or_tty->print_cr("  "
  1536                   "   used_after_gc       : %6.1fKB",
  1537                   used_after_gc / (double) K);
  1541   size_t shrink_bytes = 0;
  1542   if (capacity_until_GC < minimum_desired_capacity) {
  1543     // If we have less capacity below the metaspace HWM, then
  1544     // increment the HWM.
  1545     size_t expand_bytes = minimum_desired_capacity - capacity_until_GC;
  1546     expand_bytes = align_size_up(expand_bytes, Metaspace::commit_alignment());
  1547     // Don't expand unless it's significant
  1548     if (expand_bytes >= MinMetaspaceExpansion) {
  1549       size_t new_capacity_until_GC = 0;
  1550       bool succeeded = MetaspaceGC::inc_capacity_until_GC(expand_bytes, &new_capacity_until_GC);
  1551       assert(succeeded, "Should always succesfully increment HWM when at safepoint");
  1553       Metaspace::tracer()->report_gc_threshold(capacity_until_GC,
  1554                                                new_capacity_until_GC,
  1555                                                MetaspaceGCThresholdUpdater::ComputeNewSize);
  1556       if (PrintGCDetails && Verbose) {
  1557         gclog_or_tty->print_cr("    expanding:"
  1558                       "  minimum_desired_capacity: %6.1fKB"
  1559                       "  expand_bytes: %6.1fKB"
  1560                       "  MinMetaspaceExpansion: %6.1fKB"
  1561                       "  new metaspace HWM:  %6.1fKB",
  1562                       minimum_desired_capacity / (double) K,
  1563                       expand_bytes / (double) K,
  1564                       MinMetaspaceExpansion / (double) K,
  1565                       new_capacity_until_GC / (double) K);
  1568     return;
  1571   // No expansion, now see if we want to shrink
  1572   // We would never want to shrink more than this
  1573   size_t max_shrink_bytes = capacity_until_GC - minimum_desired_capacity;
  1574   assert(max_shrink_bytes >= 0, err_msg("max_shrink_bytes " SIZE_FORMAT,
  1575     max_shrink_bytes));
  1577   // Should shrinking be considered?
  1578   if (MaxMetaspaceFreeRatio < 100) {
  1579     const double maximum_free_percentage = MaxMetaspaceFreeRatio / 100.0;
  1580     const double minimum_used_percentage = 1.0 - maximum_free_percentage;
  1581     const double max_tmp = used_after_gc / minimum_used_percentage;
  1582     size_t maximum_desired_capacity = (size_t)MIN2(max_tmp, double(max_uintx));
  1583     maximum_desired_capacity = MAX2(maximum_desired_capacity,
  1584                                     MetaspaceSize);
  1585     if (PrintGCDetails && Verbose) {
  1586       gclog_or_tty->print_cr("  "
  1587                              "  maximum_free_percentage: %6.2f"
  1588                              "  minimum_used_percentage: %6.2f",
  1589                              maximum_free_percentage,
  1590                              minimum_used_percentage);
  1591       gclog_or_tty->print_cr("  "
  1592                              "  minimum_desired_capacity: %6.1fKB"
  1593                              "  maximum_desired_capacity: %6.1fKB",
  1594                              minimum_desired_capacity / (double) K,
  1595                              maximum_desired_capacity / (double) K);
  1598     assert(minimum_desired_capacity <= maximum_desired_capacity,
  1599            "sanity check");
  1601     if (capacity_until_GC > maximum_desired_capacity) {
  1602       // Capacity too large, compute shrinking size
  1603       shrink_bytes = capacity_until_GC - maximum_desired_capacity;
  1604       // We don't want shrink all the way back to initSize if people call
  1605       // System.gc(), because some programs do that between "phases" and then
  1606       // we'd just have to grow the heap up again for the next phase.  So we
  1607       // damp the shrinking: 0% on the first call, 10% on the second call, 40%
  1608       // on the third call, and 100% by the fourth call.  But if we recompute
  1609       // size without shrinking, it goes back to 0%.
  1610       shrink_bytes = shrink_bytes / 100 * current_shrink_factor;
  1612       shrink_bytes = align_size_down(shrink_bytes, Metaspace::commit_alignment());
  1614       assert(shrink_bytes <= max_shrink_bytes,
  1615         err_msg("invalid shrink size " SIZE_FORMAT " not <= " SIZE_FORMAT,
  1616           shrink_bytes, max_shrink_bytes));
  1617       if (current_shrink_factor == 0) {
  1618         _shrink_factor = 10;
  1619       } else {
  1620         _shrink_factor = MIN2(current_shrink_factor * 4, (uint) 100);
  1622       if (PrintGCDetails && Verbose) {
  1623         gclog_or_tty->print_cr("  "
  1624                       "  shrinking:"
  1625                       "  initSize: %.1fK"
  1626                       "  maximum_desired_capacity: %.1fK",
  1627                       MetaspaceSize / (double) K,
  1628                       maximum_desired_capacity / (double) K);
  1629         gclog_or_tty->print_cr("  "
  1630                       "  shrink_bytes: %.1fK"
  1631                       "  current_shrink_factor: %d"
  1632                       "  new shrink factor: %d"
  1633                       "  MinMetaspaceExpansion: %.1fK",
  1634                       shrink_bytes / (double) K,
  1635                       current_shrink_factor,
  1636                       _shrink_factor,
  1637                       MinMetaspaceExpansion / (double) K);
  1642   // Don't shrink unless it's significant
  1643   if (shrink_bytes >= MinMetaspaceExpansion &&
  1644       ((capacity_until_GC - shrink_bytes) >= MetaspaceSize)) {
  1645     size_t new_capacity_until_GC = MetaspaceGC::dec_capacity_until_GC(shrink_bytes);
  1646     Metaspace::tracer()->report_gc_threshold(capacity_until_GC,
  1647                                              new_capacity_until_GC,
  1648                                              MetaspaceGCThresholdUpdater::ComputeNewSize);
  1652 // Metadebug methods
  1654 void Metadebug::init_allocation_fail_alot_count() {
  1655   if (MetadataAllocationFailALot) {
  1656     _allocation_fail_alot_count =
  1657       1+(long)((double)MetadataAllocationFailALotInterval*os::random()/(max_jint+1.0));
  1661 #ifdef ASSERT
  1662 bool Metadebug::test_metadata_failure() {
  1663   if (MetadataAllocationFailALot &&
  1664       Threads::is_vm_complete()) {
  1665     if (_allocation_fail_alot_count > 0) {
  1666       _allocation_fail_alot_count--;
  1667     } else {
  1668       if (TraceMetadataChunkAllocation && Verbose) {
  1669         gclog_or_tty->print_cr("Metadata allocation failing for "
  1670                                "MetadataAllocationFailALot");
  1672       init_allocation_fail_alot_count();
  1673       return true;
  1676   return false;
  1678 #endif
  1680 // ChunkManager methods
  1682 size_t ChunkManager::free_chunks_total_words() {
  1683   return _free_chunks_total;
  1686 size_t ChunkManager::free_chunks_total_bytes() {
  1687   return free_chunks_total_words() * BytesPerWord;
  1690 size_t ChunkManager::free_chunks_count() {
  1691 #ifdef ASSERT
  1692   if (!UseConcMarkSweepGC && !SpaceManager::expand_lock()->is_locked()) {
  1693     MutexLockerEx cl(SpaceManager::expand_lock(),
  1694                      Mutex::_no_safepoint_check_flag);
  1695     // This lock is only needed in debug because the verification
  1696     // of the _free_chunks_totals walks the list of free chunks
  1697     slow_locked_verify_free_chunks_count();
  1699 #endif
  1700   return _free_chunks_count;
  1703 void ChunkManager::locked_verify_free_chunks_total() {
  1704   assert_lock_strong(SpaceManager::expand_lock());
  1705   assert(sum_free_chunks() == _free_chunks_total,
  1706     err_msg("_free_chunks_total " SIZE_FORMAT " is not the"
  1707            " same as sum " SIZE_FORMAT, _free_chunks_total,
  1708            sum_free_chunks()));
  1711 void ChunkManager::verify_free_chunks_total() {
  1712   MutexLockerEx cl(SpaceManager::expand_lock(),
  1713                      Mutex::_no_safepoint_check_flag);
  1714   locked_verify_free_chunks_total();
  1717 void ChunkManager::locked_verify_free_chunks_count() {
  1718   assert_lock_strong(SpaceManager::expand_lock());
  1719   assert(sum_free_chunks_count() == _free_chunks_count,
  1720     err_msg("_free_chunks_count " SIZE_FORMAT " is not the"
  1721            " same as sum " SIZE_FORMAT, _free_chunks_count,
  1722            sum_free_chunks_count()));
  1725 void ChunkManager::verify_free_chunks_count() {
  1726 #ifdef ASSERT
  1727   MutexLockerEx cl(SpaceManager::expand_lock(),
  1728                      Mutex::_no_safepoint_check_flag);
  1729   locked_verify_free_chunks_count();
  1730 #endif
  1733 void ChunkManager::verify() {
  1734   MutexLockerEx cl(SpaceManager::expand_lock(),
  1735                      Mutex::_no_safepoint_check_flag);
  1736   locked_verify();
  1739 void ChunkManager::locked_verify() {
  1740   locked_verify_free_chunks_count();
  1741   locked_verify_free_chunks_total();
  1744 void ChunkManager::locked_print_free_chunks(outputStream* st) {
  1745   assert_lock_strong(SpaceManager::expand_lock());
  1746   st->print_cr("Free chunk total " SIZE_FORMAT "  count " SIZE_FORMAT,
  1747                 _free_chunks_total, _free_chunks_count);
  1750 void ChunkManager::locked_print_sum_free_chunks(outputStream* st) {
  1751   assert_lock_strong(SpaceManager::expand_lock());
  1752   st->print_cr("Sum free chunk total " SIZE_FORMAT "  count " SIZE_FORMAT,
  1753                 sum_free_chunks(), sum_free_chunks_count());
  1756 ChunkList* ChunkManager::free_chunks(ChunkIndex index) {
  1757   assert(index == SpecializedIndex || index == SmallIndex || index == MediumIndex,
  1758          err_msg("Bad index: %d", (int)index));
  1760   return &_free_chunks[index];
  1763 // These methods that sum the free chunk lists are used in printing
  1764 // methods that are used in product builds.
  1765 size_t ChunkManager::sum_free_chunks() {
  1766   assert_lock_strong(SpaceManager::expand_lock());
  1767   size_t result = 0;
  1768   for (ChunkIndex i = ZeroIndex; i < NumberOfFreeLists; i = next_chunk_index(i)) {
  1769     ChunkList* list = free_chunks(i);
  1771     if (list == NULL) {
  1772       continue;
  1775     result = result + list->count() * list->size();
  1777   result = result + humongous_dictionary()->total_size();
  1778   return result;
  1781 size_t ChunkManager::sum_free_chunks_count() {
  1782   assert_lock_strong(SpaceManager::expand_lock());
  1783   size_t count = 0;
  1784   for (ChunkIndex i = ZeroIndex; i < NumberOfFreeLists; i = next_chunk_index(i)) {
  1785     ChunkList* list = free_chunks(i);
  1786     if (list == NULL) {
  1787       continue;
  1789     count = count + list->count();
  1791   count = count + humongous_dictionary()->total_free_blocks();
  1792   return count;
  1795 ChunkList* ChunkManager::find_free_chunks_list(size_t word_size) {
  1796   ChunkIndex index = list_index(word_size);
  1797   assert(index < HumongousIndex, "No humongous list");
  1798   return free_chunks(index);
  1801 Metachunk* ChunkManager::free_chunks_get(size_t word_size) {
  1802   assert_lock_strong(SpaceManager::expand_lock());
  1804   slow_locked_verify();
  1806   Metachunk* chunk = NULL;
  1807   if (list_index(word_size) != HumongousIndex) {
  1808     ChunkList* free_list = find_free_chunks_list(word_size);
  1809     assert(free_list != NULL, "Sanity check");
  1811     chunk = free_list->head();
  1813     if (chunk == NULL) {
  1814       return NULL;
  1817     // Remove the chunk as the head of the list.
  1818     free_list->remove_chunk(chunk);
  1820     if (TraceMetadataChunkAllocation && Verbose) {
  1821       gclog_or_tty->print_cr("ChunkManager::free_chunks_get: free_list "
  1822                              PTR_FORMAT " head " PTR_FORMAT " size " SIZE_FORMAT,
  1823                              free_list, chunk, chunk->word_size());
  1825   } else {
  1826     chunk = humongous_dictionary()->get_chunk(
  1827       word_size,
  1828       FreeBlockDictionary<Metachunk>::atLeast);
  1830     if (chunk == NULL) {
  1831       return NULL;
  1834     if (TraceMetadataHumongousAllocation) {
  1835       size_t waste = chunk->word_size() - word_size;
  1836       gclog_or_tty->print_cr("Free list allocate humongous chunk size "
  1837                              SIZE_FORMAT " for requested size " SIZE_FORMAT
  1838                              " waste " SIZE_FORMAT,
  1839                              chunk->word_size(), word_size, waste);
  1843   // Chunk is being removed from the chunks free list.
  1844   dec_free_chunks_total(chunk->word_size());
  1846   // Remove it from the links to this freelist
  1847   chunk->set_next(NULL);
  1848   chunk->set_prev(NULL);
  1849 #ifdef ASSERT
  1850   // Chunk is no longer on any freelist. Setting to false make container_count_slow()
  1851   // work.
  1852   chunk->set_is_tagged_free(false);
  1853 #endif
  1854   chunk->container()->inc_container_count();
  1856   slow_locked_verify();
  1857   return chunk;
  1860 Metachunk* ChunkManager::chunk_freelist_allocate(size_t word_size) {
  1861   assert_lock_strong(SpaceManager::expand_lock());
  1862   slow_locked_verify();
  1864   // Take from the beginning of the list
  1865   Metachunk* chunk = free_chunks_get(word_size);
  1866   if (chunk == NULL) {
  1867     return NULL;
  1870   assert((word_size <= chunk->word_size()) ||
  1871          (list_index(chunk->word_size()) == HumongousIndex),
  1872          "Non-humongous variable sized chunk");
  1873   if (TraceMetadataChunkAllocation) {
  1874     size_t list_count;
  1875     if (list_index(word_size) < HumongousIndex) {
  1876       ChunkList* list = find_free_chunks_list(word_size);
  1877       list_count = list->count();
  1878     } else {
  1879       list_count = humongous_dictionary()->total_count();
  1881     gclog_or_tty->print("ChunkManager::chunk_freelist_allocate: " PTR_FORMAT " chunk "
  1882                         PTR_FORMAT "  size " SIZE_FORMAT " count " SIZE_FORMAT " ",
  1883                         this, chunk, chunk->word_size(), list_count);
  1884     locked_print_free_chunks(gclog_or_tty);
  1887   return chunk;
  1890 void ChunkManager::print_on(outputStream* out) const {
  1891   if (PrintFLSStatistics != 0) {
  1892     const_cast<ChunkManager *>(this)->humongous_dictionary()->report_statistics();
  1896 // SpaceManager methods
  1898 size_t SpaceManager::adjust_initial_chunk_size(size_t requested, bool is_class_space) {
  1899   size_t chunk_sizes[] = {
  1900       specialized_chunk_size(is_class_space),
  1901       small_chunk_size(is_class_space),
  1902       medium_chunk_size(is_class_space)
  1903   };
  1905   // Adjust up to one of the fixed chunk sizes ...
  1906   for (size_t i = 0; i < ARRAY_SIZE(chunk_sizes); i++) {
  1907     if (requested <= chunk_sizes[i]) {
  1908       return chunk_sizes[i];
  1912   // ... or return the size as a humongous chunk.
  1913   return requested;
  1916 size_t SpaceManager::adjust_initial_chunk_size(size_t requested) const {
  1917   return adjust_initial_chunk_size(requested, is_class());
  1920 size_t SpaceManager::get_initial_chunk_size(Metaspace::MetaspaceType type) const {
  1921   size_t requested;
  1923   if (is_class()) {
  1924     switch (type) {
  1925     case Metaspace::BootMetaspaceType:       requested = Metaspace::first_class_chunk_word_size(); break;
  1926     case Metaspace::ROMetaspaceType:         requested = ClassSpecializedChunk; break;
  1927     case Metaspace::ReadWriteMetaspaceType:  requested = ClassSpecializedChunk; break;
  1928     case Metaspace::AnonymousMetaspaceType:  requested = ClassSpecializedChunk; break;
  1929     case Metaspace::ReflectionMetaspaceType: requested = ClassSpecializedChunk; break;
  1930     default:                                 requested = ClassSmallChunk; break;
  1932   } else {
  1933     switch (type) {
  1934     case Metaspace::BootMetaspaceType:       requested = Metaspace::first_chunk_word_size(); break;
  1935     case Metaspace::ROMetaspaceType:         requested = SharedReadOnlySize / wordSize; break;
  1936     case Metaspace::ReadWriteMetaspaceType:  requested = SharedReadWriteSize / wordSize; break;
  1937     case Metaspace::AnonymousMetaspaceType:  requested = SpecializedChunk; break;
  1938     case Metaspace::ReflectionMetaspaceType: requested = SpecializedChunk; break;
  1939     default:                                 requested = SmallChunk; break;
  1943   // Adjust to one of the fixed chunk sizes (unless humongous)
  1944   const size_t adjusted = adjust_initial_chunk_size(requested);
  1946   assert(adjusted != 0, err_msg("Incorrect initial chunk size. Requested: "
  1947          SIZE_FORMAT " adjusted: " SIZE_FORMAT, requested, adjusted));
  1949   return adjusted;
  1952 size_t SpaceManager::sum_free_in_chunks_in_use() const {
  1953   MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag);
  1954   size_t free = 0;
  1955   for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) {
  1956     Metachunk* chunk = chunks_in_use(i);
  1957     while (chunk != NULL) {
  1958       free += chunk->free_word_size();
  1959       chunk = chunk->next();
  1962   return free;
  1965 size_t SpaceManager::sum_waste_in_chunks_in_use() const {
  1966   MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag);
  1967   size_t result = 0;
  1968   for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) {
  1969    result += sum_waste_in_chunks_in_use(i);
  1972   return result;
  1975 size_t SpaceManager::sum_waste_in_chunks_in_use(ChunkIndex index) const {
  1976   size_t result = 0;
  1977   Metachunk* chunk = chunks_in_use(index);
  1978   // Count the free space in all the chunk but not the
  1979   // current chunk from which allocations are still being done.
  1980   while (chunk != NULL) {
  1981     if (chunk != current_chunk()) {
  1982       result += chunk->free_word_size();
  1984     chunk = chunk->next();
  1986   return result;
  1989 size_t SpaceManager::sum_capacity_in_chunks_in_use() const {
  1990   // For CMS use "allocated_chunks_words()" which does not need the
  1991   // Metaspace lock.  For the other collectors sum over the
  1992   // lists.  Use both methods as a check that "allocated_chunks_words()"
  1993   // is correct.  That is, sum_capacity_in_chunks() is too expensive
  1994   // to use in the product and allocated_chunks_words() should be used
  1995   // but allow for  checking that allocated_chunks_words() returns the same
  1996   // value as sum_capacity_in_chunks_in_use() which is the definitive
  1997   // answer.
  1998   if (UseConcMarkSweepGC) {
  1999     return allocated_chunks_words();
  2000   } else {
  2001     MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag);
  2002     size_t sum = 0;
  2003     for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) {
  2004       Metachunk* chunk = chunks_in_use(i);
  2005       while (chunk != NULL) {
  2006         sum += chunk->word_size();
  2007         chunk = chunk->next();
  2010   return sum;
  2014 size_t SpaceManager::sum_count_in_chunks_in_use() {
  2015   size_t count = 0;
  2016   for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) {
  2017     count = count + sum_count_in_chunks_in_use(i);
  2020   return count;
  2023 size_t SpaceManager::sum_count_in_chunks_in_use(ChunkIndex i) {
  2024   size_t count = 0;
  2025   Metachunk* chunk = chunks_in_use(i);
  2026   while (chunk != NULL) {
  2027     count++;
  2028     chunk = chunk->next();
  2030   return count;
  2034 size_t SpaceManager::sum_used_in_chunks_in_use() const {
  2035   MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag);
  2036   size_t used = 0;
  2037   for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) {
  2038     Metachunk* chunk = chunks_in_use(i);
  2039     while (chunk != NULL) {
  2040       used += chunk->used_word_size();
  2041       chunk = chunk->next();
  2044   return used;
  2047 void SpaceManager::locked_print_chunks_in_use_on(outputStream* st) const {
  2049   for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) {
  2050     Metachunk* chunk = chunks_in_use(i);
  2051     st->print("SpaceManager: %s " PTR_FORMAT,
  2052                  chunk_size_name(i), chunk);
  2053     if (chunk != NULL) {
  2054       st->print_cr(" free " SIZE_FORMAT,
  2055                    chunk->free_word_size());
  2056     } else {
  2057       st->cr();
  2061   chunk_manager()->locked_print_free_chunks(st);
  2062   chunk_manager()->locked_print_sum_free_chunks(st);
  2065 size_t SpaceManager::calc_chunk_size(size_t word_size) {
  2067   // Decide between a small chunk and a medium chunk.  Up to
  2068   // _small_chunk_limit small chunks can be allocated but
  2069   // once a medium chunk has been allocated, no more small
  2070   // chunks will be allocated.
  2071   size_t chunk_word_size;
  2072   if (chunks_in_use(MediumIndex) == NULL &&
  2073       sum_count_in_chunks_in_use(SmallIndex) < _small_chunk_limit) {
  2074     chunk_word_size = (size_t) small_chunk_size();
  2075     if (word_size + Metachunk::overhead() > small_chunk_size()) {
  2076       chunk_word_size = medium_chunk_size();
  2078   } else {
  2079     chunk_word_size = medium_chunk_size();
  2082   // Might still need a humongous chunk.  Enforce
  2083   // humongous allocations sizes to be aligned up to
  2084   // the smallest chunk size.
  2085   size_t if_humongous_sized_chunk =
  2086     align_size_up(word_size + Metachunk::overhead(),
  2087                   smallest_chunk_size());
  2088   chunk_word_size =
  2089     MAX2((size_t) chunk_word_size, if_humongous_sized_chunk);
  2091   assert(!SpaceManager::is_humongous(word_size) ||
  2092          chunk_word_size == if_humongous_sized_chunk,
  2093          err_msg("Size calculation is wrong, word_size " SIZE_FORMAT
  2094                  " chunk_word_size " SIZE_FORMAT,
  2095                  word_size, chunk_word_size));
  2096   if (TraceMetadataHumongousAllocation &&
  2097       SpaceManager::is_humongous(word_size)) {
  2098     gclog_or_tty->print_cr("Metadata humongous allocation:");
  2099     gclog_or_tty->print_cr("  word_size " PTR_FORMAT, word_size);
  2100     gclog_or_tty->print_cr("  chunk_word_size " PTR_FORMAT,
  2101                            chunk_word_size);
  2102     gclog_or_tty->print_cr("    chunk overhead " PTR_FORMAT,
  2103                            Metachunk::overhead());
  2105   return chunk_word_size;
  2108 void SpaceManager::track_metaspace_memory_usage() {
  2109   if (is_init_completed()) {
  2110     if (is_class()) {
  2111       MemoryService::track_compressed_class_memory_usage();
  2113     MemoryService::track_metaspace_memory_usage();
  2117 MetaWord* SpaceManager::grow_and_allocate(size_t word_size) {
  2118   assert(vs_list()->current_virtual_space() != NULL,
  2119          "Should have been set");
  2120   assert(current_chunk() == NULL ||
  2121          current_chunk()->allocate(word_size) == NULL,
  2122          "Don't need to expand");
  2123   MutexLockerEx cl(SpaceManager::expand_lock(), Mutex::_no_safepoint_check_flag);
  2125   if (TraceMetadataChunkAllocation && Verbose) {
  2126     size_t words_left = 0;
  2127     size_t words_used = 0;
  2128     if (current_chunk() != NULL) {
  2129       words_left = current_chunk()->free_word_size();
  2130       words_used = current_chunk()->used_word_size();
  2132     gclog_or_tty->print_cr("SpaceManager::grow_and_allocate for " SIZE_FORMAT
  2133                            " words " SIZE_FORMAT " words used " SIZE_FORMAT
  2134                            " words left",
  2135                             word_size, words_used, words_left);
  2138   // Get another chunk out of the virtual space
  2139   size_t chunk_word_size = calc_chunk_size(word_size);
  2140   Metachunk* next = get_new_chunk(chunk_word_size);
  2142   MetaWord* mem = NULL;
  2144   // If a chunk was available, add it to the in-use chunk list
  2145   // and do an allocation from it.
  2146   if (next != NULL) {
  2147     // Add to this manager's list of chunks in use.
  2148     add_chunk(next, false);
  2149     mem = next->allocate(word_size);
  2152   // Track metaspace memory usage statistic.
  2153   track_metaspace_memory_usage();
  2155   return mem;
  2158 void SpaceManager::print_on(outputStream* st) const {
  2160   for (ChunkIndex i = ZeroIndex;
  2161        i < NumberOfInUseLists ;
  2162        i = next_chunk_index(i) ) {
  2163     st->print_cr("  chunks_in_use " PTR_FORMAT " chunk size " PTR_FORMAT,
  2164                  chunks_in_use(i),
  2165                  chunks_in_use(i) == NULL ? 0 : chunks_in_use(i)->word_size());
  2167   st->print_cr("    waste:  Small " SIZE_FORMAT " Medium " SIZE_FORMAT
  2168                " Humongous " SIZE_FORMAT,
  2169                sum_waste_in_chunks_in_use(SmallIndex),
  2170                sum_waste_in_chunks_in_use(MediumIndex),
  2171                sum_waste_in_chunks_in_use(HumongousIndex));
  2172   // block free lists
  2173   if (block_freelists() != NULL) {
  2174     st->print_cr("total in block free lists " SIZE_FORMAT,
  2175       block_freelists()->total_size());
  2179 SpaceManager::SpaceManager(Metaspace::MetadataType mdtype,
  2180                            Mutex* lock) :
  2181   _mdtype(mdtype),
  2182   _allocated_blocks_words(0),
  2183   _allocated_chunks_words(0),
  2184   _allocated_chunks_count(0),
  2185   _lock(lock)
  2187   initialize();
  2190 void SpaceManager::inc_size_metrics(size_t words) {
  2191   assert_lock_strong(SpaceManager::expand_lock());
  2192   // Total of allocated Metachunks and allocated Metachunks count
  2193   // for each SpaceManager
  2194   _allocated_chunks_words = _allocated_chunks_words + words;
  2195   _allocated_chunks_count++;
  2196   // Global total of capacity in allocated Metachunks
  2197   MetaspaceAux::inc_capacity(mdtype(), words);
  2198   // Global total of allocated Metablocks.
  2199   // used_words_slow() includes the overhead in each
  2200   // Metachunk so include it in the used when the
  2201   // Metachunk is first added (so only added once per
  2202   // Metachunk).
  2203   MetaspaceAux::inc_used(mdtype(), Metachunk::overhead());
  2206 void SpaceManager::inc_used_metrics(size_t words) {
  2207   // Add to the per SpaceManager total
  2208   Atomic::add_ptr(words, &_allocated_blocks_words);
  2209   // Add to the global total
  2210   MetaspaceAux::inc_used(mdtype(), words);
  2213 void SpaceManager::dec_total_from_size_metrics() {
  2214   MetaspaceAux::dec_capacity(mdtype(), allocated_chunks_words());
  2215   MetaspaceAux::dec_used(mdtype(), allocated_blocks_words());
  2216   // Also deduct the overhead per Metachunk
  2217   MetaspaceAux::dec_used(mdtype(), allocated_chunks_count() * Metachunk::overhead());
  2220 void SpaceManager::initialize() {
  2221   Metadebug::init_allocation_fail_alot_count();
  2222   for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) {
  2223     _chunks_in_use[i] = NULL;
  2225   _current_chunk = NULL;
  2226   if (TraceMetadataChunkAllocation && Verbose) {
  2227     gclog_or_tty->print_cr("SpaceManager(): " PTR_FORMAT, this);
  2231 void ChunkManager::return_chunks(ChunkIndex index, Metachunk* chunks) {
  2232   if (chunks == NULL) {
  2233     return;
  2235   ChunkList* list = free_chunks(index);
  2236   assert(list->size() == chunks->word_size(), "Mismatch in chunk sizes");
  2237   assert_lock_strong(SpaceManager::expand_lock());
  2238   Metachunk* cur = chunks;
  2240   // This returns chunks one at a time.  If a new
  2241   // class List can be created that is a base class
  2242   // of FreeList then something like FreeList::prepend()
  2243   // can be used in place of this loop
  2244   while (cur != NULL) {
  2245     assert(cur->container() != NULL, "Container should have been set");
  2246     cur->container()->dec_container_count();
  2247     // Capture the next link before it is changed
  2248     // by the call to return_chunk_at_head();
  2249     Metachunk* next = cur->next();
  2250     DEBUG_ONLY(cur->set_is_tagged_free(true);)
  2251     list->return_chunk_at_head(cur);
  2252     cur = next;
  2256 SpaceManager::~SpaceManager() {
  2257   // This call this->_lock which can't be done while holding expand_lock()
  2258   assert(sum_capacity_in_chunks_in_use() == allocated_chunks_words(),
  2259     err_msg("sum_capacity_in_chunks_in_use() " SIZE_FORMAT
  2260             " allocated_chunks_words() " SIZE_FORMAT,
  2261             sum_capacity_in_chunks_in_use(), allocated_chunks_words()));
  2263   MutexLockerEx fcl(SpaceManager::expand_lock(),
  2264                     Mutex::_no_safepoint_check_flag);
  2266   chunk_manager()->slow_locked_verify();
  2268   dec_total_from_size_metrics();
  2270   if (TraceMetadataChunkAllocation && Verbose) {
  2271     gclog_or_tty->print_cr("~SpaceManager(): " PTR_FORMAT, this);
  2272     locked_print_chunks_in_use_on(gclog_or_tty);
  2275   // Do not mangle freed Metachunks.  The chunk size inside Metachunks
  2276   // is during the freeing of a VirtualSpaceNodes.
  2278   // Have to update before the chunks_in_use lists are emptied
  2279   // below.
  2280   chunk_manager()->inc_free_chunks_total(allocated_chunks_words(),
  2281                                          sum_count_in_chunks_in_use());
  2283   // Add all the chunks in use by this space manager
  2284   // to the global list of free chunks.
  2286   // Follow each list of chunks-in-use and add them to the
  2287   // free lists.  Each list is NULL terminated.
  2289   for (ChunkIndex i = ZeroIndex; i < HumongousIndex; i = next_chunk_index(i)) {
  2290     if (TraceMetadataChunkAllocation && Verbose) {
  2291       gclog_or_tty->print_cr("returned %d %s chunks to freelist",
  2292                              sum_count_in_chunks_in_use(i),
  2293                              chunk_size_name(i));
  2295     Metachunk* chunks = chunks_in_use(i);
  2296     chunk_manager()->return_chunks(i, chunks);
  2297     set_chunks_in_use(i, NULL);
  2298     if (TraceMetadataChunkAllocation && Verbose) {
  2299       gclog_or_tty->print_cr("updated freelist count %d %s",
  2300                              chunk_manager()->free_chunks(i)->count(),
  2301                              chunk_size_name(i));
  2303     assert(i != HumongousIndex, "Humongous chunks are handled explicitly later");
  2306   // The medium chunk case may be optimized by passing the head and
  2307   // tail of the medium chunk list to add_at_head().  The tail is often
  2308   // the current chunk but there are probably exceptions.
  2310   // Humongous chunks
  2311   if (TraceMetadataChunkAllocation && Verbose) {
  2312     gclog_or_tty->print_cr("returned %d %s humongous chunks to dictionary",
  2313                             sum_count_in_chunks_in_use(HumongousIndex),
  2314                             chunk_size_name(HumongousIndex));
  2315     gclog_or_tty->print("Humongous chunk dictionary: ");
  2317   // Humongous chunks are never the current chunk.
  2318   Metachunk* humongous_chunks = chunks_in_use(HumongousIndex);
  2320   while (humongous_chunks != NULL) {
  2321 #ifdef ASSERT
  2322     humongous_chunks->set_is_tagged_free(true);
  2323 #endif
  2324     if (TraceMetadataChunkAllocation && Verbose) {
  2325       gclog_or_tty->print(PTR_FORMAT " (" SIZE_FORMAT ") ",
  2326                           humongous_chunks,
  2327                           humongous_chunks->word_size());
  2329     assert(humongous_chunks->word_size() == (size_t)
  2330            align_size_up(humongous_chunks->word_size(),
  2331                              smallest_chunk_size()),
  2332            err_msg("Humongous chunk size is wrong: word size " SIZE_FORMAT
  2333                    " granularity %d",
  2334                    humongous_chunks->word_size(), smallest_chunk_size()));
  2335     Metachunk* next_humongous_chunks = humongous_chunks->next();
  2336     humongous_chunks->container()->dec_container_count();
  2337     chunk_manager()->humongous_dictionary()->return_chunk(humongous_chunks);
  2338     humongous_chunks = next_humongous_chunks;
  2340   if (TraceMetadataChunkAllocation && Verbose) {
  2341     gclog_or_tty->cr();
  2342     gclog_or_tty->print_cr("updated dictionary count %d %s",
  2343                      chunk_manager()->humongous_dictionary()->total_count(),
  2344                      chunk_size_name(HumongousIndex));
  2346   chunk_manager()->slow_locked_verify();
  2349 const char* SpaceManager::chunk_size_name(ChunkIndex index) const {
  2350   switch (index) {
  2351     case SpecializedIndex:
  2352       return "Specialized";
  2353     case SmallIndex:
  2354       return "Small";
  2355     case MediumIndex:
  2356       return "Medium";
  2357     case HumongousIndex:
  2358       return "Humongous";
  2359     default:
  2360       return NULL;
  2364 ChunkIndex ChunkManager::list_index(size_t size) {
  2365   if (free_chunks(SpecializedIndex)->size() == size) {
  2366     return SpecializedIndex;
  2368   if (free_chunks(SmallIndex)->size() == size) {
  2369     return SmallIndex;
  2371   if (free_chunks(MediumIndex)->size() == size) {
  2372     return MediumIndex;
  2375   assert(size > free_chunks(MediumIndex)->size(), "Not a humongous chunk");
  2376   return HumongousIndex;
  2379 void SpaceManager::deallocate(MetaWord* p, size_t word_size) {
  2380   assert_lock_strong(_lock);
  2381   size_t raw_word_size = get_raw_word_size(word_size);
  2382   size_t min_size = TreeChunk<Metablock, FreeList<Metablock> >::min_size();
  2383   assert(raw_word_size >= min_size,
  2384          err_msg("Should not deallocate dark matter " SIZE_FORMAT "<" SIZE_FORMAT, word_size, min_size));
  2385   block_freelists()->return_block(p, raw_word_size);
  2388 // Adds a chunk to the list of chunks in use.
  2389 void SpaceManager::add_chunk(Metachunk* new_chunk, bool make_current) {
  2391   assert(new_chunk != NULL, "Should not be NULL");
  2392   assert(new_chunk->next() == NULL, "Should not be on a list");
  2394   new_chunk->reset_empty();
  2396   // Find the correct list and and set the current
  2397   // chunk for that list.
  2398   ChunkIndex index = chunk_manager()->list_index(new_chunk->word_size());
  2400   if (index != HumongousIndex) {
  2401     retire_current_chunk();
  2402     set_current_chunk(new_chunk);
  2403     new_chunk->set_next(chunks_in_use(index));
  2404     set_chunks_in_use(index, new_chunk);
  2405   } else {
  2406     // For null class loader data and DumpSharedSpaces, the first chunk isn't
  2407     // small, so small will be null.  Link this first chunk as the current
  2408     // chunk.
  2409     if (make_current) {
  2410       // Set as the current chunk but otherwise treat as a humongous chunk.
  2411       set_current_chunk(new_chunk);
  2413     // Link at head.  The _current_chunk only points to a humongous chunk for
  2414     // the null class loader metaspace (class and data virtual space managers)
  2415     // any humongous chunks so will not point to the tail
  2416     // of the humongous chunks list.
  2417     new_chunk->set_next(chunks_in_use(HumongousIndex));
  2418     set_chunks_in_use(HumongousIndex, new_chunk);
  2420     assert(new_chunk->word_size() > medium_chunk_size(), "List inconsistency");
  2423   // Add to the running sum of capacity
  2424   inc_size_metrics(new_chunk->word_size());
  2426   assert(new_chunk->is_empty(), "Not ready for reuse");
  2427   if (TraceMetadataChunkAllocation && Verbose) {
  2428     gclog_or_tty->print("SpaceManager::add_chunk: %d) ",
  2429                         sum_count_in_chunks_in_use());
  2430     new_chunk->print_on(gclog_or_tty);
  2431     chunk_manager()->locked_print_free_chunks(gclog_or_tty);
  2435 void SpaceManager::retire_current_chunk() {
  2436   if (current_chunk() != NULL) {
  2437     size_t remaining_words = current_chunk()->free_word_size();
  2438     if (remaining_words >= TreeChunk<Metablock, FreeList<Metablock> >::min_size()) {
  2439       block_freelists()->return_block(current_chunk()->allocate(remaining_words), remaining_words);
  2440       inc_used_metrics(remaining_words);
  2445 Metachunk* SpaceManager::get_new_chunk(size_t chunk_word_size) {
  2446   // Get a chunk from the chunk freelist
  2447   Metachunk* next = chunk_manager()->chunk_freelist_allocate(chunk_word_size);
  2449   if (next == NULL) {
  2450     next = vs_list()->get_new_chunk(chunk_word_size,
  2451                                     medium_chunk_bunch());
  2454   if (TraceMetadataHumongousAllocation && next != NULL &&
  2455       SpaceManager::is_humongous(next->word_size())) {
  2456     gclog_or_tty->print_cr("  new humongous chunk word size "
  2457                            PTR_FORMAT, next->word_size());
  2460   return next;
  2463 MetaWord* SpaceManager::allocate(size_t word_size) {
  2464   MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag);
  2466   size_t raw_word_size = get_raw_word_size(word_size);
  2467   BlockFreelist* fl =  block_freelists();
  2468   MetaWord* p = NULL;
  2469   // Allocation from the dictionary is expensive in the sense that
  2470   // the dictionary has to be searched for a size.  Don't allocate
  2471   // from the dictionary until it starts to get fat.  Is this
  2472   // a reasonable policy?  Maybe an skinny dictionary is fast enough
  2473   // for allocations.  Do some profiling.  JJJ
  2474   if (fl->total_size() > allocation_from_dictionary_limit) {
  2475     p = fl->get_block(raw_word_size);
  2477   if (p == NULL) {
  2478     p = allocate_work(raw_word_size);
  2481   return p;
  2484 // Returns the address of spaced allocated for "word_size".
  2485 // This methods does not know about blocks (Metablocks)
  2486 MetaWord* SpaceManager::allocate_work(size_t word_size) {
  2487   assert_lock_strong(_lock);
  2488 #ifdef ASSERT
  2489   if (Metadebug::test_metadata_failure()) {
  2490     return NULL;
  2492 #endif
  2493   // Is there space in the current chunk?
  2494   MetaWord* result = NULL;
  2496   // For DumpSharedSpaces, only allocate out of the current chunk which is
  2497   // never null because we gave it the size we wanted.   Caller reports out
  2498   // of memory if this returns null.
  2499   if (DumpSharedSpaces) {
  2500     assert(current_chunk() != NULL, "should never happen");
  2501     inc_used_metrics(word_size);
  2502     return current_chunk()->allocate(word_size); // caller handles null result
  2505   if (current_chunk() != NULL) {
  2506     result = current_chunk()->allocate(word_size);
  2509   if (result == NULL) {
  2510     result = grow_and_allocate(word_size);
  2513   if (result != NULL) {
  2514     inc_used_metrics(word_size);
  2515     assert(result != (MetaWord*) chunks_in_use(MediumIndex),
  2516            "Head of the list is being allocated");
  2519   return result;
  2522 void SpaceManager::verify() {
  2523   // If there are blocks in the dictionary, then
  2524   // verfication of chunks does not work since
  2525   // being in the dictionary alters a chunk.
  2526   if (block_freelists()->total_size() == 0) {
  2527     for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) {
  2528       Metachunk* curr = chunks_in_use(i);
  2529       while (curr != NULL) {
  2530         curr->verify();
  2531         verify_chunk_size(curr);
  2532         curr = curr->next();
  2538 void SpaceManager::verify_chunk_size(Metachunk* chunk) {
  2539   assert(is_humongous(chunk->word_size()) ||
  2540          chunk->word_size() == medium_chunk_size() ||
  2541          chunk->word_size() == small_chunk_size() ||
  2542          chunk->word_size() == specialized_chunk_size(),
  2543          "Chunk size is wrong");
  2544   return;
  2547 #ifdef ASSERT
  2548 void SpaceManager::verify_allocated_blocks_words() {
  2549   // Verification is only guaranteed at a safepoint.
  2550   assert(SafepointSynchronize::is_at_safepoint() || !Universe::is_fully_initialized(),
  2551     "Verification can fail if the applications is running");
  2552   assert(allocated_blocks_words() == sum_used_in_chunks_in_use(),
  2553     err_msg("allocation total is not consistent " SIZE_FORMAT
  2554             " vs " SIZE_FORMAT,
  2555             allocated_blocks_words(), sum_used_in_chunks_in_use()));
  2558 #endif
  2560 void SpaceManager::dump(outputStream* const out) const {
  2561   size_t curr_total = 0;
  2562   size_t waste = 0;
  2563   uint i = 0;
  2564   size_t used = 0;
  2565   size_t capacity = 0;
  2567   // Add up statistics for all chunks in this SpaceManager.
  2568   for (ChunkIndex index = ZeroIndex;
  2569        index < NumberOfInUseLists;
  2570        index = next_chunk_index(index)) {
  2571     for (Metachunk* curr = chunks_in_use(index);
  2572          curr != NULL;
  2573          curr = curr->next()) {
  2574       out->print("%d) ", i++);
  2575       curr->print_on(out);
  2576       curr_total += curr->word_size();
  2577       used += curr->used_word_size();
  2578       capacity += curr->word_size();
  2579       waste += curr->free_word_size() + curr->overhead();;
  2583   if (TraceMetadataChunkAllocation && Verbose) {
  2584     block_freelists()->print_on(out);
  2587   size_t free = current_chunk() == NULL ? 0 : current_chunk()->free_word_size();
  2588   // Free space isn't wasted.
  2589   waste -= free;
  2591   out->print_cr("total of all chunks "  SIZE_FORMAT " used " SIZE_FORMAT
  2592                 " free " SIZE_FORMAT " capacity " SIZE_FORMAT
  2593                 " waste " SIZE_FORMAT, curr_total, used, free, capacity, waste);
  2596 #ifndef PRODUCT
  2597 void SpaceManager::mangle_freed_chunks() {
  2598   for (ChunkIndex index = ZeroIndex;
  2599        index < NumberOfInUseLists;
  2600        index = next_chunk_index(index)) {
  2601     for (Metachunk* curr = chunks_in_use(index);
  2602          curr != NULL;
  2603          curr = curr->next()) {
  2604       curr->mangle();
  2608 #endif // PRODUCT
  2610 // MetaspaceAux
  2613 size_t MetaspaceAux::_capacity_words[] = {0, 0};
  2614 size_t MetaspaceAux::_used_words[] = {0, 0};
  2616 size_t MetaspaceAux::free_bytes(Metaspace::MetadataType mdtype) {
  2617   VirtualSpaceList* list = Metaspace::get_space_list(mdtype);
  2618   return list == NULL ? 0 : list->free_bytes();
  2621 size_t MetaspaceAux::free_bytes() {
  2622   return free_bytes(Metaspace::ClassType) + free_bytes(Metaspace::NonClassType);
  2625 void MetaspaceAux::dec_capacity(Metaspace::MetadataType mdtype, size_t words) {
  2626   assert_lock_strong(SpaceManager::expand_lock());
  2627   assert(words <= capacity_words(mdtype),
  2628     err_msg("About to decrement below 0: words " SIZE_FORMAT
  2629             " is greater than _capacity_words[%u] " SIZE_FORMAT,
  2630             words, mdtype, capacity_words(mdtype)));
  2631   _capacity_words[mdtype] -= words;
  2634 void MetaspaceAux::inc_capacity(Metaspace::MetadataType mdtype, size_t words) {
  2635   assert_lock_strong(SpaceManager::expand_lock());
  2636   // Needs to be atomic
  2637   _capacity_words[mdtype] += words;
  2640 void MetaspaceAux::dec_used(Metaspace::MetadataType mdtype, size_t words) {
  2641   assert(words <= used_words(mdtype),
  2642     err_msg("About to decrement below 0: words " SIZE_FORMAT
  2643             " is greater than _used_words[%u] " SIZE_FORMAT,
  2644             words, mdtype, used_words(mdtype)));
  2645   // For CMS deallocation of the Metaspaces occurs during the
  2646   // sweep which is a concurrent phase.  Protection by the expand_lock()
  2647   // is not enough since allocation is on a per Metaspace basis
  2648   // and protected by the Metaspace lock.
  2649   jlong minus_words = (jlong) - (jlong) words;
  2650   Atomic::add_ptr(minus_words, &_used_words[mdtype]);
  2653 void MetaspaceAux::inc_used(Metaspace::MetadataType mdtype, size_t words) {
  2654   // _used_words tracks allocations for
  2655   // each piece of metadata.  Those allocations are
  2656   // generally done concurrently by different application
  2657   // threads so must be done atomically.
  2658   Atomic::add_ptr(words, &_used_words[mdtype]);
  2661 size_t MetaspaceAux::used_bytes_slow(Metaspace::MetadataType mdtype) {
  2662   size_t used = 0;
  2663   ClassLoaderDataGraphMetaspaceIterator iter;
  2664   while (iter.repeat()) {
  2665     Metaspace* msp = iter.get_next();
  2666     // Sum allocated_blocks_words for each metaspace
  2667     if (msp != NULL) {
  2668       used += msp->used_words_slow(mdtype);
  2671   return used * BytesPerWord;
  2674 size_t MetaspaceAux::free_bytes_slow(Metaspace::MetadataType mdtype) {
  2675   size_t free = 0;
  2676   ClassLoaderDataGraphMetaspaceIterator iter;
  2677   while (iter.repeat()) {
  2678     Metaspace* msp = iter.get_next();
  2679     if (msp != NULL) {
  2680       free += msp->free_words_slow(mdtype);
  2683   return free * BytesPerWord;
  2686 size_t MetaspaceAux::capacity_bytes_slow(Metaspace::MetadataType mdtype) {
  2687   if ((mdtype == Metaspace::ClassType) && !Metaspace::using_class_space()) {
  2688     return 0;
  2690   // Don't count the space in the freelists.  That space will be
  2691   // added to the capacity calculation as needed.
  2692   size_t capacity = 0;
  2693   ClassLoaderDataGraphMetaspaceIterator iter;
  2694   while (iter.repeat()) {
  2695     Metaspace* msp = iter.get_next();
  2696     if (msp != NULL) {
  2697       capacity += msp->capacity_words_slow(mdtype);
  2700   return capacity * BytesPerWord;
  2703 size_t MetaspaceAux::capacity_bytes_slow() {
  2704 #ifdef PRODUCT
  2705   // Use capacity_bytes() in PRODUCT instead of this function.
  2706   guarantee(false, "Should not call capacity_bytes_slow() in the PRODUCT");
  2707 #endif
  2708   size_t class_capacity = capacity_bytes_slow(Metaspace::ClassType);
  2709   size_t non_class_capacity = capacity_bytes_slow(Metaspace::NonClassType);
  2710   assert(capacity_bytes() == class_capacity + non_class_capacity,
  2711       err_msg("bad accounting: capacity_bytes() " SIZE_FORMAT
  2712         " class_capacity + non_class_capacity " SIZE_FORMAT
  2713         " class_capacity " SIZE_FORMAT " non_class_capacity " SIZE_FORMAT,
  2714         capacity_bytes(), class_capacity + non_class_capacity,
  2715         class_capacity, non_class_capacity));
  2717   return class_capacity + non_class_capacity;
  2720 size_t MetaspaceAux::reserved_bytes(Metaspace::MetadataType mdtype) {
  2721   VirtualSpaceList* list = Metaspace::get_space_list(mdtype);
  2722   return list == NULL ? 0 : list->reserved_bytes();
  2725 size_t MetaspaceAux::committed_bytes(Metaspace::MetadataType mdtype) {
  2726   VirtualSpaceList* list = Metaspace::get_space_list(mdtype);
  2727   return list == NULL ? 0 : list->committed_bytes();
  2730 size_t MetaspaceAux::min_chunk_size_words() { return Metaspace::first_chunk_word_size(); }
  2732 size_t MetaspaceAux::free_chunks_total_words(Metaspace::MetadataType mdtype) {
  2733   ChunkManager* chunk_manager = Metaspace::get_chunk_manager(mdtype);
  2734   if (chunk_manager == NULL) {
  2735     return 0;
  2737   chunk_manager->slow_verify();
  2738   return chunk_manager->free_chunks_total_words();
  2741 size_t MetaspaceAux::free_chunks_total_bytes(Metaspace::MetadataType mdtype) {
  2742   return free_chunks_total_words(mdtype) * BytesPerWord;
  2745 size_t MetaspaceAux::free_chunks_total_words() {
  2746   return free_chunks_total_words(Metaspace::ClassType) +
  2747          free_chunks_total_words(Metaspace::NonClassType);
  2750 size_t MetaspaceAux::free_chunks_total_bytes() {
  2751   return free_chunks_total_words() * BytesPerWord;
  2754 bool MetaspaceAux::has_chunk_free_list(Metaspace::MetadataType mdtype) {
  2755   return Metaspace::get_chunk_manager(mdtype) != NULL;
  2758 MetaspaceChunkFreeListSummary MetaspaceAux::chunk_free_list_summary(Metaspace::MetadataType mdtype) {
  2759   if (!has_chunk_free_list(mdtype)) {
  2760     return MetaspaceChunkFreeListSummary();
  2763   const ChunkManager* cm = Metaspace::get_chunk_manager(mdtype);
  2764   return cm->chunk_free_list_summary();
  2767 void MetaspaceAux::print_metaspace_change(size_t prev_metadata_used) {
  2768   gclog_or_tty->print(", [Metaspace:");
  2769   if (PrintGCDetails && Verbose) {
  2770     gclog_or_tty->print(" "  SIZE_FORMAT
  2771                         "->" SIZE_FORMAT
  2772                         "("  SIZE_FORMAT ")",
  2773                         prev_metadata_used,
  2774                         used_bytes(),
  2775                         reserved_bytes());
  2776   } else {
  2777     gclog_or_tty->print(" "  SIZE_FORMAT "K"
  2778                         "->" SIZE_FORMAT "K"
  2779                         "("  SIZE_FORMAT "K)",
  2780                         prev_metadata_used/K,
  2781                         used_bytes()/K,
  2782                         reserved_bytes()/K);
  2785   gclog_or_tty->print("]");
  2788 // This is printed when PrintGCDetails
  2789 void MetaspaceAux::print_on(outputStream* out) {
  2790   Metaspace::MetadataType nct = Metaspace::NonClassType;
  2792   out->print_cr(" Metaspace       "
  2793                 "used "      SIZE_FORMAT "K, "
  2794                 "capacity "  SIZE_FORMAT "K, "
  2795                 "committed " SIZE_FORMAT "K, "
  2796                 "reserved "  SIZE_FORMAT "K",
  2797                 used_bytes()/K,
  2798                 capacity_bytes()/K,
  2799                 committed_bytes()/K,
  2800                 reserved_bytes()/K);
  2802   if (Metaspace::using_class_space()) {
  2803     Metaspace::MetadataType ct = Metaspace::ClassType;
  2804     out->print_cr("  class space    "
  2805                   "used "      SIZE_FORMAT "K, "
  2806                   "capacity "  SIZE_FORMAT "K, "
  2807                   "committed " SIZE_FORMAT "K, "
  2808                   "reserved "  SIZE_FORMAT "K",
  2809                   used_bytes(ct)/K,
  2810                   capacity_bytes(ct)/K,
  2811                   committed_bytes(ct)/K,
  2812                   reserved_bytes(ct)/K);
  2816 // Print information for class space and data space separately.
  2817 // This is almost the same as above.
  2818 void MetaspaceAux::print_on(outputStream* out, Metaspace::MetadataType mdtype) {
  2819   size_t free_chunks_capacity_bytes = free_chunks_total_bytes(mdtype);
  2820   size_t capacity_bytes = capacity_bytes_slow(mdtype);
  2821   size_t used_bytes = used_bytes_slow(mdtype);
  2822   size_t free_bytes = free_bytes_slow(mdtype);
  2823   size_t used_and_free = used_bytes + free_bytes +
  2824                            free_chunks_capacity_bytes;
  2825   out->print_cr("  Chunk accounting: used in chunks " SIZE_FORMAT
  2826              "K + unused in chunks " SIZE_FORMAT "K  + "
  2827              " capacity in free chunks " SIZE_FORMAT "K = " SIZE_FORMAT
  2828              "K  capacity in allocated chunks " SIZE_FORMAT "K",
  2829              used_bytes / K,
  2830              free_bytes / K,
  2831              free_chunks_capacity_bytes / K,
  2832              used_and_free / K,
  2833              capacity_bytes / K);
  2834   // Accounting can only be correct if we got the values during a safepoint
  2835   assert(!SafepointSynchronize::is_at_safepoint() || used_and_free == capacity_bytes, "Accounting is wrong");
  2838 // Print total fragmentation for class metaspaces
  2839 void MetaspaceAux::print_class_waste(outputStream* out) {
  2840   assert(Metaspace::using_class_space(), "class metaspace not used");
  2841   size_t cls_specialized_waste = 0, cls_small_waste = 0, cls_medium_waste = 0;
  2842   size_t cls_specialized_count = 0, cls_small_count = 0, cls_medium_count = 0, cls_humongous_count = 0;
  2843   ClassLoaderDataGraphMetaspaceIterator iter;
  2844   while (iter.repeat()) {
  2845     Metaspace* msp = iter.get_next();
  2846     if (msp != NULL) {
  2847       cls_specialized_waste += msp->class_vsm()->sum_waste_in_chunks_in_use(SpecializedIndex);
  2848       cls_specialized_count += msp->class_vsm()->sum_count_in_chunks_in_use(SpecializedIndex);
  2849       cls_small_waste += msp->class_vsm()->sum_waste_in_chunks_in_use(SmallIndex);
  2850       cls_small_count += msp->class_vsm()->sum_count_in_chunks_in_use(SmallIndex);
  2851       cls_medium_waste += msp->class_vsm()->sum_waste_in_chunks_in_use(MediumIndex);
  2852       cls_medium_count += msp->class_vsm()->sum_count_in_chunks_in_use(MediumIndex);
  2853       cls_humongous_count += msp->class_vsm()->sum_count_in_chunks_in_use(HumongousIndex);
  2856   out->print_cr(" class: " SIZE_FORMAT " specialized(s) " SIZE_FORMAT ", "
  2857                 SIZE_FORMAT " small(s) " SIZE_FORMAT ", "
  2858                 SIZE_FORMAT " medium(s) " SIZE_FORMAT ", "
  2859                 "large count " SIZE_FORMAT,
  2860                 cls_specialized_count, cls_specialized_waste,
  2861                 cls_small_count, cls_small_waste,
  2862                 cls_medium_count, cls_medium_waste, cls_humongous_count);
  2865 // Print total fragmentation for data and class metaspaces separately
  2866 void MetaspaceAux::print_waste(outputStream* out) {
  2867   size_t specialized_waste = 0, small_waste = 0, medium_waste = 0;
  2868   size_t specialized_count = 0, small_count = 0, medium_count = 0, humongous_count = 0;
  2870   ClassLoaderDataGraphMetaspaceIterator iter;
  2871   while (iter.repeat()) {
  2872     Metaspace* msp = iter.get_next();
  2873     if (msp != NULL) {
  2874       specialized_waste += msp->vsm()->sum_waste_in_chunks_in_use(SpecializedIndex);
  2875       specialized_count += msp->vsm()->sum_count_in_chunks_in_use(SpecializedIndex);
  2876       small_waste += msp->vsm()->sum_waste_in_chunks_in_use(SmallIndex);
  2877       small_count += msp->vsm()->sum_count_in_chunks_in_use(SmallIndex);
  2878       medium_waste += msp->vsm()->sum_waste_in_chunks_in_use(MediumIndex);
  2879       medium_count += msp->vsm()->sum_count_in_chunks_in_use(MediumIndex);
  2880       humongous_count += msp->vsm()->sum_count_in_chunks_in_use(HumongousIndex);
  2883   out->print_cr("Total fragmentation waste (words) doesn't count free space");
  2884   out->print_cr("  data: " SIZE_FORMAT " specialized(s) " SIZE_FORMAT ", "
  2885                         SIZE_FORMAT " small(s) " SIZE_FORMAT ", "
  2886                         SIZE_FORMAT " medium(s) " SIZE_FORMAT ", "
  2887                         "large count " SIZE_FORMAT,
  2888              specialized_count, specialized_waste, small_count,
  2889              small_waste, medium_count, medium_waste, humongous_count);
  2890   if (Metaspace::using_class_space()) {
  2891     print_class_waste(out);
  2895 // Dump global metaspace things from the end of ClassLoaderDataGraph
  2896 void MetaspaceAux::dump(outputStream* out) {
  2897   out->print_cr("All Metaspace:");
  2898   out->print("data space: "); print_on(out, Metaspace::NonClassType);
  2899   out->print("class space: "); print_on(out, Metaspace::ClassType);
  2900   print_waste(out);
  2903 void MetaspaceAux::verify_free_chunks() {
  2904   Metaspace::chunk_manager_metadata()->verify();
  2905   if (Metaspace::using_class_space()) {
  2906     Metaspace::chunk_manager_class()->verify();
  2910 void MetaspaceAux::verify_capacity() {
  2911 #ifdef ASSERT
  2912   size_t running_sum_capacity_bytes = capacity_bytes();
  2913   // For purposes of the running sum of capacity, verify against capacity
  2914   size_t capacity_in_use_bytes = capacity_bytes_slow();
  2915   assert(running_sum_capacity_bytes == capacity_in_use_bytes,
  2916     err_msg("capacity_words() * BytesPerWord " SIZE_FORMAT
  2917             " capacity_bytes_slow()" SIZE_FORMAT,
  2918             running_sum_capacity_bytes, capacity_in_use_bytes));
  2919   for (Metaspace::MetadataType i = Metaspace::ClassType;
  2920        i < Metaspace:: MetadataTypeCount;
  2921        i = (Metaspace::MetadataType)(i + 1)) {
  2922     size_t capacity_in_use_bytes = capacity_bytes_slow(i);
  2923     assert(capacity_bytes(i) == capacity_in_use_bytes,
  2924       err_msg("capacity_bytes(%u) " SIZE_FORMAT
  2925               " capacity_bytes_slow(%u)" SIZE_FORMAT,
  2926               i, capacity_bytes(i), i, capacity_in_use_bytes));
  2928 #endif
  2931 void MetaspaceAux::verify_used() {
  2932 #ifdef ASSERT
  2933   size_t running_sum_used_bytes = used_bytes();
  2934   // For purposes of the running sum of used, verify against used
  2935   size_t used_in_use_bytes = used_bytes_slow();
  2936   assert(used_bytes() == used_in_use_bytes,
  2937     err_msg("used_bytes() " SIZE_FORMAT
  2938             " used_bytes_slow()" SIZE_FORMAT,
  2939             used_bytes(), used_in_use_bytes));
  2940   for (Metaspace::MetadataType i = Metaspace::ClassType;
  2941        i < Metaspace:: MetadataTypeCount;
  2942        i = (Metaspace::MetadataType)(i + 1)) {
  2943     size_t used_in_use_bytes = used_bytes_slow(i);
  2944     assert(used_bytes(i) == used_in_use_bytes,
  2945       err_msg("used_bytes(%u) " SIZE_FORMAT
  2946               " used_bytes_slow(%u)" SIZE_FORMAT,
  2947               i, used_bytes(i), i, used_in_use_bytes));
  2949 #endif
  2952 void MetaspaceAux::verify_metrics() {
  2953   verify_capacity();
  2954   verify_used();
  2958 // Metaspace methods
  2960 size_t Metaspace::_first_chunk_word_size = 0;
  2961 size_t Metaspace::_first_class_chunk_word_size = 0;
  2963 size_t Metaspace::_commit_alignment = 0;
  2964 size_t Metaspace::_reserve_alignment = 0;
  2966 Metaspace::Metaspace(Mutex* lock, MetaspaceType type) {
  2967   initialize(lock, type);
  2970 Metaspace::~Metaspace() {
  2971   delete _vsm;
  2972   if (using_class_space()) {
  2973     delete _class_vsm;
  2977 VirtualSpaceList* Metaspace::_space_list = NULL;
  2978 VirtualSpaceList* Metaspace::_class_space_list = NULL;
  2980 ChunkManager* Metaspace::_chunk_manager_metadata = NULL;
  2981 ChunkManager* Metaspace::_chunk_manager_class = NULL;
  2983 #define VIRTUALSPACEMULTIPLIER 2
  2985 #ifdef _LP64
  2986 static const uint64_t UnscaledClassSpaceMax = (uint64_t(max_juint) + 1);
  2988 void Metaspace::set_narrow_klass_base_and_shift(address metaspace_base, address cds_base) {
  2989   // Figure out the narrow_klass_base and the narrow_klass_shift.  The
  2990   // narrow_klass_base is the lower of the metaspace base and the cds base
  2991   // (if cds is enabled).  The narrow_klass_shift depends on the distance
  2992   // between the lower base and higher address.
  2993   address lower_base;
  2994   address higher_address;
  2995 #if INCLUDE_CDS
  2996   if (UseSharedSpaces) {
  2997     higher_address = MAX2((address)(cds_base + FileMapInfo::shared_spaces_size()),
  2998                           (address)(metaspace_base + compressed_class_space_size()));
  2999     lower_base = MIN2(metaspace_base, cds_base);
  3000   } else
  3001 #endif
  3003     higher_address = metaspace_base + compressed_class_space_size();
  3004     lower_base = metaspace_base;
  3006     uint64_t klass_encoding_max = UnscaledClassSpaceMax << LogKlassAlignmentInBytes;
  3007     // If compressed class space fits in lower 32G, we don't need a base.
  3008     if (higher_address <= (address)klass_encoding_max) {
  3009       lower_base = 0; // effectively lower base is zero.
  3013   Universe::set_narrow_klass_base(lower_base);
  3015   if ((uint64_t)(higher_address - lower_base) <= UnscaledClassSpaceMax) {
  3016     Universe::set_narrow_klass_shift(0);
  3017   } else {
  3018     assert(!UseSharedSpaces, "Cannot shift with UseSharedSpaces");
  3019     Universe::set_narrow_klass_shift(LogKlassAlignmentInBytes);
  3023 #if INCLUDE_CDS
  3024 // Return TRUE if the specified metaspace_base and cds_base are close enough
  3025 // to work with compressed klass pointers.
  3026 bool Metaspace::can_use_cds_with_metaspace_addr(char* metaspace_base, address cds_base) {
  3027   assert(cds_base != 0 && UseSharedSpaces, "Only use with CDS");
  3028   assert(UseCompressedClassPointers, "Only use with CompressedKlassPtrs");
  3029   address lower_base = MIN2((address)metaspace_base, cds_base);
  3030   address higher_address = MAX2((address)(cds_base + FileMapInfo::shared_spaces_size()),
  3031                                 (address)(metaspace_base + compressed_class_space_size()));
  3032   return ((uint64_t)(higher_address - lower_base) <= UnscaledClassSpaceMax);
  3034 #endif
  3036 // Try to allocate the metaspace at the requested addr.
  3037 void Metaspace::allocate_metaspace_compressed_klass_ptrs(char* requested_addr, address cds_base) {
  3038   assert(using_class_space(), "called improperly");
  3039   assert(UseCompressedClassPointers, "Only use with CompressedKlassPtrs");
  3040   assert(compressed_class_space_size() < KlassEncodingMetaspaceMax,
  3041          "Metaspace size is too big");
  3042   assert_is_ptr_aligned(requested_addr, _reserve_alignment);
  3043   assert_is_ptr_aligned(cds_base, _reserve_alignment);
  3044   assert_is_size_aligned(compressed_class_space_size(), _reserve_alignment);
  3046   // Don't use large pages for the class space.
  3047   bool large_pages = false;
  3049   ReservedSpace metaspace_rs = ReservedSpace(compressed_class_space_size(),
  3050                                              _reserve_alignment,
  3051                                              large_pages,
  3052                                              requested_addr, 0);
  3053   if (!metaspace_rs.is_reserved()) {
  3054 #if INCLUDE_CDS
  3055     if (UseSharedSpaces) {
  3056       size_t increment = align_size_up(1*G, _reserve_alignment);
  3058       // Keep trying to allocate the metaspace, increasing the requested_addr
  3059       // by 1GB each time, until we reach an address that will no longer allow
  3060       // use of CDS with compressed klass pointers.
  3061       char *addr = requested_addr;
  3062       while (!metaspace_rs.is_reserved() && (addr + increment > addr) &&
  3063              can_use_cds_with_metaspace_addr(addr + increment, cds_base)) {
  3064         addr = addr + increment;
  3065         metaspace_rs = ReservedSpace(compressed_class_space_size(),
  3066                                      _reserve_alignment, large_pages, addr, 0);
  3069 #endif
  3070     // If no successful allocation then try to allocate the space anywhere.  If
  3071     // that fails then OOM doom.  At this point we cannot try allocating the
  3072     // metaspace as if UseCompressedClassPointers is off because too much
  3073     // initialization has happened that depends on UseCompressedClassPointers.
  3074     // So, UseCompressedClassPointers cannot be turned off at this point.
  3075     if (!metaspace_rs.is_reserved()) {
  3076       metaspace_rs = ReservedSpace(compressed_class_space_size(),
  3077                                    _reserve_alignment, large_pages);
  3078       if (!metaspace_rs.is_reserved()) {
  3079         vm_exit_during_initialization(err_msg("Could not allocate metaspace: %d bytes",
  3080                                               compressed_class_space_size()));
  3085   // If we got here then the metaspace got allocated.
  3086   MemTracker::record_virtual_memory_type((address)metaspace_rs.base(), mtClass);
  3088 #if INCLUDE_CDS
  3089   // Verify that we can use shared spaces.  Otherwise, turn off CDS.
  3090   if (UseSharedSpaces && !can_use_cds_with_metaspace_addr(metaspace_rs.base(), cds_base)) {
  3091     FileMapInfo::stop_sharing_and_unmap(
  3092         "Could not allocate metaspace at a compatible address");
  3094 #endif
  3095   set_narrow_klass_base_and_shift((address)metaspace_rs.base(),
  3096                                   UseSharedSpaces ? (address)cds_base : 0);
  3098   initialize_class_space(metaspace_rs);
  3100   if (PrintCompressedOopsMode || (PrintMiscellaneous && Verbose)) {
  3101     gclog_or_tty->print_cr("Narrow klass base: " PTR_FORMAT ", Narrow klass shift: " SIZE_FORMAT,
  3102                             Universe::narrow_klass_base(), Universe::narrow_klass_shift());
  3103     gclog_or_tty->print_cr("Compressed class space size: " SIZE_FORMAT " Address: " PTR_FORMAT " Req Addr: " PTR_FORMAT,
  3104                            compressed_class_space_size(), metaspace_rs.base(), requested_addr);
  3108 // For UseCompressedClassPointers the class space is reserved above the top of
  3109 // the Java heap.  The argument passed in is at the base of the compressed space.
  3110 void Metaspace::initialize_class_space(ReservedSpace rs) {
  3111   // The reserved space size may be bigger because of alignment, esp with UseLargePages
  3112   assert(rs.size() >= CompressedClassSpaceSize,
  3113          err_msg(SIZE_FORMAT " != " UINTX_FORMAT, rs.size(), CompressedClassSpaceSize));
  3114   assert(using_class_space(), "Must be using class space");
  3115   _class_space_list = new VirtualSpaceList(rs);
  3116   _chunk_manager_class = new ChunkManager(ClassSpecializedChunk, ClassSmallChunk, ClassMediumChunk);
  3118   if (!_class_space_list->initialization_succeeded()) {
  3119     vm_exit_during_initialization("Failed to setup compressed class space virtual space list.");
  3123 #endif
  3125 void Metaspace::ergo_initialize() {
  3126   if (DumpSharedSpaces) {
  3127     // Using large pages when dumping the shared archive is currently not implemented.
  3128     FLAG_SET_ERGO(bool, UseLargePagesInMetaspace, false);
  3131   size_t page_size = os::vm_page_size();
  3132   if (UseLargePages && UseLargePagesInMetaspace) {
  3133     page_size = os::large_page_size();
  3136   _commit_alignment  = page_size;
  3137   _reserve_alignment = MAX2(page_size, (size_t)os::vm_allocation_granularity());
  3139   // Do not use FLAG_SET_ERGO to update MaxMetaspaceSize, since this will
  3140   // override if MaxMetaspaceSize was set on the command line or not.
  3141   // This information is needed later to conform to the specification of the
  3142   // java.lang.management.MemoryUsage API.
  3143   //
  3144   // Ideally, we would be able to set the default value of MaxMetaspaceSize in
  3145   // globals.hpp to the aligned value, but this is not possible, since the
  3146   // alignment depends on other flags being parsed.
  3147   MaxMetaspaceSize = align_size_down_bounded(MaxMetaspaceSize, _reserve_alignment);
  3149   if (MetaspaceSize > MaxMetaspaceSize) {
  3150     MetaspaceSize = MaxMetaspaceSize;
  3153   MetaspaceSize = align_size_down_bounded(MetaspaceSize, _commit_alignment);
  3155   assert(MetaspaceSize <= MaxMetaspaceSize, "MetaspaceSize should be limited by MaxMetaspaceSize");
  3157   if (MetaspaceSize < 256*K) {
  3158     vm_exit_during_initialization("Too small initial Metaspace size");
  3161   MinMetaspaceExpansion = align_size_down_bounded(MinMetaspaceExpansion, _commit_alignment);
  3162   MaxMetaspaceExpansion = align_size_down_bounded(MaxMetaspaceExpansion, _commit_alignment);
  3164   CompressedClassSpaceSize = align_size_down_bounded(CompressedClassSpaceSize, _reserve_alignment);
  3165   set_compressed_class_space_size(CompressedClassSpaceSize);
  3167   // Initial virtual space size will be calculated at global_initialize()
  3168   uintx min_metaspace_sz =
  3169       VIRTUALSPACEMULTIPLIER * InitialBootClassLoaderMetaspaceSize;
  3170   if (UseCompressedClassPointers) {
  3171     if ((min_metaspace_sz + CompressedClassSpaceSize) >  MaxMetaspaceSize) {
  3172       if (min_metaspace_sz >= MaxMetaspaceSize) {
  3173         vm_exit_during_initialization("MaxMetaspaceSize is too small.");
  3174       } else {
  3175         FLAG_SET_ERGO(uintx, CompressedClassSpaceSize,
  3176                       MaxMetaspaceSize - min_metaspace_sz);
  3179   } else if (min_metaspace_sz >= MaxMetaspaceSize) {
  3180     FLAG_SET_ERGO(uintx, InitialBootClassLoaderMetaspaceSize,
  3181                   min_metaspace_sz);
  3186 void Metaspace::global_initialize() {
  3187   MetaspaceGC::initialize();
  3189   // Initialize the alignment for shared spaces.
  3190   int max_alignment = os::vm_allocation_granularity();
  3191   size_t cds_total = 0;
  3193   MetaspaceShared::set_max_alignment(max_alignment);
  3195   if (DumpSharedSpaces) {
  3196 #if INCLUDE_CDS
  3197     MetaspaceShared::estimate_regions_size();
  3199     SharedReadOnlySize  = align_size_up(SharedReadOnlySize,  max_alignment);
  3200     SharedReadWriteSize = align_size_up(SharedReadWriteSize, max_alignment);
  3201     SharedMiscDataSize  = align_size_up(SharedMiscDataSize,  max_alignment);
  3202     SharedMiscCodeSize  = align_size_up(SharedMiscCodeSize,  max_alignment);
  3204     // the min_misc_code_size estimate is based on MetaspaceShared::generate_vtable_methods()
  3205     uintx min_misc_code_size = align_size_up(
  3206       (MetaspaceShared::num_virtuals * MetaspaceShared::vtbl_list_size) *
  3207         (sizeof(void*) + MetaspaceShared::vtbl_method_size) + MetaspaceShared::vtbl_common_code_size,
  3208           max_alignment);
  3210     if (SharedMiscCodeSize < min_misc_code_size) {
  3211       report_out_of_shared_space(SharedMiscCode);
  3214     // Initialize with the sum of the shared space sizes.  The read-only
  3215     // and read write metaspace chunks will be allocated out of this and the
  3216     // remainder is the misc code and data chunks.
  3217     cds_total = FileMapInfo::shared_spaces_size();
  3218     cds_total = align_size_up(cds_total, _reserve_alignment);
  3219     _space_list = new VirtualSpaceList(cds_total/wordSize);
  3220     _chunk_manager_metadata = new ChunkManager(SpecializedChunk, SmallChunk, MediumChunk);
  3222     if (!_space_list->initialization_succeeded()) {
  3223       vm_exit_during_initialization("Unable to dump shared archive.", NULL);
  3226 #ifdef _LP64
  3227     if (cds_total + compressed_class_space_size() > UnscaledClassSpaceMax) {
  3228       vm_exit_during_initialization("Unable to dump shared archive.",
  3229           err_msg("Size of archive (" SIZE_FORMAT ") + compressed class space ("
  3230                   SIZE_FORMAT ") == total (" SIZE_FORMAT ") is larger than compressed "
  3231                   "klass limit: " SIZE_FORMAT, cds_total, compressed_class_space_size(),
  3232                   cds_total + compressed_class_space_size(), UnscaledClassSpaceMax));
  3235     // Set the compressed klass pointer base so that decoding of these pointers works
  3236     // properly when creating the shared archive.
  3237     assert(UseCompressedOops && UseCompressedClassPointers,
  3238       "UseCompressedOops and UseCompressedClassPointers must be set");
  3239     Universe::set_narrow_klass_base((address)_space_list->current_virtual_space()->bottom());
  3240     if (TraceMetavirtualspaceAllocation && Verbose) {
  3241       gclog_or_tty->print_cr("Setting_narrow_klass_base to Address: " PTR_FORMAT,
  3242                              _space_list->current_virtual_space()->bottom());
  3245     Universe::set_narrow_klass_shift(0);
  3246 #endif // _LP64
  3247 #endif // INCLUDE_CDS
  3248   } else {
  3249 #if INCLUDE_CDS
  3250     // If using shared space, open the file that contains the shared space
  3251     // and map in the memory before initializing the rest of metaspace (so
  3252     // the addresses don't conflict)
  3253     address cds_address = NULL;
  3254     if (UseSharedSpaces) {
  3255       FileMapInfo* mapinfo = new FileMapInfo();
  3257       // Open the shared archive file, read and validate the header. If
  3258       // initialization fails, shared spaces [UseSharedSpaces] are
  3259       // disabled and the file is closed.
  3260       // Map in spaces now also
  3261       if (mapinfo->initialize() && MetaspaceShared::map_shared_spaces(mapinfo)) {
  3262         cds_total = FileMapInfo::shared_spaces_size();
  3263         cds_address = (address)mapinfo->region_base(0);
  3264       } else {
  3265         assert(!mapinfo->is_open() && !UseSharedSpaces,
  3266                "archive file not closed or shared spaces not disabled.");
  3269 #endif // INCLUDE_CDS
  3270 #ifdef _LP64
  3271     // If UseCompressedClassPointers is set then allocate the metaspace area
  3272     // above the heap and above the CDS area (if it exists).
  3273     if (using_class_space()) {
  3274       if (UseSharedSpaces) {
  3275 #if INCLUDE_CDS
  3276         char* cds_end = (char*)(cds_address + cds_total);
  3277         cds_end = (char *)align_ptr_up(cds_end, _reserve_alignment);
  3278         allocate_metaspace_compressed_klass_ptrs(cds_end, cds_address);
  3279 #endif
  3280       } else {
  3281         char* base = (char*)align_ptr_up(Universe::heap()->reserved_region().end(), _reserve_alignment);
  3282         allocate_metaspace_compressed_klass_ptrs(base, 0);
  3285 #endif // _LP64
  3287     // Initialize these before initializing the VirtualSpaceList
  3288     _first_chunk_word_size = InitialBootClassLoaderMetaspaceSize / BytesPerWord;
  3289     _first_chunk_word_size = align_word_size_up(_first_chunk_word_size);
  3290     // Make the first class chunk bigger than a medium chunk so it's not put
  3291     // on the medium chunk list.   The next chunk will be small and progress
  3292     // from there.  This size calculated by -version.
  3293     _first_class_chunk_word_size = MIN2((size_t)MediumChunk*6,
  3294                                        (CompressedClassSpaceSize/BytesPerWord)*2);
  3295     _first_class_chunk_word_size = align_word_size_up(_first_class_chunk_word_size);
  3296     // Arbitrarily set the initial virtual space to a multiple
  3297     // of the boot class loader size.
  3298     size_t word_size = VIRTUALSPACEMULTIPLIER * _first_chunk_word_size;
  3299     word_size = align_size_up(word_size, Metaspace::reserve_alignment_words());
  3301     // Initialize the list of virtual spaces.
  3302     _space_list = new VirtualSpaceList(word_size);
  3303     _chunk_manager_metadata = new ChunkManager(SpecializedChunk, SmallChunk, MediumChunk);
  3305     if (!_space_list->initialization_succeeded()) {
  3306       vm_exit_during_initialization("Unable to setup metadata virtual space list.", NULL);
  3310   _tracer = new MetaspaceTracer();
  3313 void Metaspace::post_initialize() {
  3314   MetaspaceGC::post_initialize();
  3317 void Metaspace::initialize_first_chunk(MetaspaceType type, MetadataType mdtype) {
  3318   Metachunk* chunk = get_initialization_chunk(type, mdtype);
  3319   if (chunk != NULL) {
  3320     // Add to this manager's list of chunks in use and current_chunk().
  3321     get_space_manager(mdtype)->add_chunk(chunk, true);
  3325 Metachunk* Metaspace::get_initialization_chunk(MetaspaceType type, MetadataType mdtype) {
  3326   size_t chunk_word_size = get_space_manager(mdtype)->get_initial_chunk_size(type);
  3328   // Get a chunk from the chunk freelist
  3329   Metachunk* chunk = get_chunk_manager(mdtype)->chunk_freelist_allocate(chunk_word_size);
  3331   if (chunk == NULL) {
  3332     chunk = get_space_list(mdtype)->get_new_chunk(chunk_word_size,
  3333                                                   get_space_manager(mdtype)->medium_chunk_bunch());
  3336   // For dumping shared archive, report error if allocation has failed.
  3337   if (DumpSharedSpaces && chunk == NULL) {
  3338     report_insufficient_metaspace(MetaspaceAux::committed_bytes() + chunk_word_size * BytesPerWord);
  3341   return chunk;
  3344 void Metaspace::verify_global_initialization() {
  3345   assert(space_list() != NULL, "Metadata VirtualSpaceList has not been initialized");
  3346   assert(chunk_manager_metadata() != NULL, "Metadata ChunkManager has not been initialized");
  3348   if (using_class_space()) {
  3349     assert(class_space_list() != NULL, "Class VirtualSpaceList has not been initialized");
  3350     assert(chunk_manager_class() != NULL, "Class ChunkManager has not been initialized");
  3354 void Metaspace::initialize(Mutex* lock, MetaspaceType type) {
  3355   verify_global_initialization();
  3357   // Allocate SpaceManager for metadata objects.
  3358   _vsm = new SpaceManager(NonClassType, lock);
  3360   if (using_class_space()) {
  3361     // Allocate SpaceManager for classes.
  3362     _class_vsm = new SpaceManager(ClassType, lock);
  3365   MutexLockerEx cl(SpaceManager::expand_lock(), Mutex::_no_safepoint_check_flag);
  3367   // Allocate chunk for metadata objects
  3368   initialize_first_chunk(type, NonClassType);
  3370   // Allocate chunk for class metadata objects
  3371   if (using_class_space()) {
  3372     initialize_first_chunk(type, ClassType);
  3375   _alloc_record_head = NULL;
  3376   _alloc_record_tail = NULL;
  3379 size_t Metaspace::align_word_size_up(size_t word_size) {
  3380   size_t byte_size = word_size * wordSize;
  3381   return ReservedSpace::allocation_align_size_up(byte_size) / wordSize;
  3384 MetaWord* Metaspace::allocate(size_t word_size, MetadataType mdtype) {
  3385   // DumpSharedSpaces doesn't use class metadata area (yet)
  3386   // Also, don't use class_vsm() unless UseCompressedClassPointers is true.
  3387   if (is_class_space_allocation(mdtype)) {
  3388     return  class_vsm()->allocate(word_size);
  3389   } else {
  3390     return  vsm()->allocate(word_size);
  3394 MetaWord* Metaspace::expand_and_allocate(size_t word_size, MetadataType mdtype) {
  3395   size_t delta_bytes = MetaspaceGC::delta_capacity_until_GC(word_size * BytesPerWord);
  3396   assert(delta_bytes > 0, "Must be");
  3398   size_t before = 0;
  3399   size_t after = 0;
  3400   MetaWord* res;
  3401   bool incremented;
  3403   // Each thread increments the HWM at most once. Even if the thread fails to increment
  3404   // the HWM, an allocation is still attempted. This is because another thread must then
  3405   // have incremented the HWM and therefore the allocation might still succeed.
  3406   do {
  3407     incremented = MetaspaceGC::inc_capacity_until_GC(delta_bytes, &after, &before);
  3408     res = allocate(word_size, mdtype);
  3409   } while (!incremented && res == NULL);
  3411   if (incremented) {
  3412     tracer()->report_gc_threshold(before, after,
  3413                                   MetaspaceGCThresholdUpdater::ExpandAndAllocate);
  3414     if (PrintGCDetails && Verbose) {
  3415       gclog_or_tty->print_cr("Increase capacity to GC from " SIZE_FORMAT
  3416           " to " SIZE_FORMAT, before, after);
  3420   return res;
  3423 // Space allocated in the Metaspace.  This may
  3424 // be across several metadata virtual spaces.
  3425 char* Metaspace::bottom() const {
  3426   assert(DumpSharedSpaces, "only useful and valid for dumping shared spaces");
  3427   return (char*)vsm()->current_chunk()->bottom();
  3430 size_t Metaspace::used_words_slow(MetadataType mdtype) const {
  3431   if (mdtype == ClassType) {
  3432     return using_class_space() ? class_vsm()->sum_used_in_chunks_in_use() : 0;
  3433   } else {
  3434     return vsm()->sum_used_in_chunks_in_use();  // includes overhead!
  3438 size_t Metaspace::free_words_slow(MetadataType mdtype) const {
  3439   if (mdtype == ClassType) {
  3440     return using_class_space() ? class_vsm()->sum_free_in_chunks_in_use() : 0;
  3441   } else {
  3442     return vsm()->sum_free_in_chunks_in_use();
  3446 // Space capacity in the Metaspace.  It includes
  3447 // space in the list of chunks from which allocations
  3448 // have been made. Don't include space in the global freelist and
  3449 // in the space available in the dictionary which
  3450 // is already counted in some chunk.
  3451 size_t Metaspace::capacity_words_slow(MetadataType mdtype) const {
  3452   if (mdtype == ClassType) {
  3453     return using_class_space() ? class_vsm()->sum_capacity_in_chunks_in_use() : 0;
  3454   } else {
  3455     return vsm()->sum_capacity_in_chunks_in_use();
  3459 size_t Metaspace::used_bytes_slow(MetadataType mdtype) const {
  3460   return used_words_slow(mdtype) * BytesPerWord;
  3463 size_t Metaspace::capacity_bytes_slow(MetadataType mdtype) const {
  3464   return capacity_words_slow(mdtype) * BytesPerWord;
  3467 size_t Metaspace::allocated_blocks_bytes() const {
  3468   return vsm()->allocated_blocks_bytes() +
  3469       (using_class_space() ? class_vsm()->allocated_blocks_bytes() : 0);
  3472 size_t Metaspace::allocated_chunks_bytes() const {
  3473   return vsm()->allocated_chunks_bytes() +
  3474       (using_class_space() ? class_vsm()->allocated_chunks_bytes() : 0);
  3477 void Metaspace::deallocate(MetaWord* ptr, size_t word_size, bool is_class) {
  3478   if (SafepointSynchronize::is_at_safepoint()) {
  3479     if (DumpSharedSpaces && PrintSharedSpaces) {
  3480       record_deallocation(ptr, vsm()->get_raw_word_size(word_size));
  3483     assert(Thread::current()->is_VM_thread(), "should be the VM thread");
  3484     // Don't take Heap_lock
  3485     MutexLockerEx ml(vsm()->lock(), Mutex::_no_safepoint_check_flag);
  3486     if (word_size < TreeChunk<Metablock, FreeList<Metablock> >::min_size()) {
  3487       // Dark matter.  Too small for dictionary.
  3488 #ifdef ASSERT
  3489       Copy::fill_to_words((HeapWord*)ptr, word_size, 0xf5f5f5f5);
  3490 #endif
  3491       return;
  3493     if (is_class && using_class_space()) {
  3494       class_vsm()->deallocate(ptr, word_size);
  3495     } else {
  3496       vsm()->deallocate(ptr, word_size);
  3498   } else {
  3499     MutexLockerEx ml(vsm()->lock(), Mutex::_no_safepoint_check_flag);
  3501     if (word_size < TreeChunk<Metablock, FreeList<Metablock> >::min_size()) {
  3502       // Dark matter.  Too small for dictionary.
  3503 #ifdef ASSERT
  3504       Copy::fill_to_words((HeapWord*)ptr, word_size, 0xf5f5f5f5);
  3505 #endif
  3506       return;
  3508     if (is_class && using_class_space()) {
  3509       class_vsm()->deallocate(ptr, word_size);
  3510     } else {
  3511       vsm()->deallocate(ptr, word_size);
  3517 MetaWord* Metaspace::allocate(ClassLoaderData* loader_data, size_t word_size,
  3518                               bool read_only, MetaspaceObj::Type type, TRAPS) {
  3519   if (HAS_PENDING_EXCEPTION) {
  3520     assert(false, "Should not allocate with exception pending");
  3521     return NULL;  // caller does a CHECK_NULL too
  3524   assert(loader_data != NULL, "Should never pass around a NULL loader_data. "
  3525         "ClassLoaderData::the_null_class_loader_data() should have been used.");
  3527   // Allocate in metaspaces without taking out a lock, because it deadlocks
  3528   // with the SymbolTable_lock.  Dumping is single threaded for now.  We'll have
  3529   // to revisit this for application class data sharing.
  3530   if (DumpSharedSpaces) {
  3531     assert(type > MetaspaceObj::UnknownType && type < MetaspaceObj::_number_of_types, "sanity");
  3532     Metaspace* space = read_only ? loader_data->ro_metaspace() : loader_data->rw_metaspace();
  3533     MetaWord* result = space->allocate(word_size, NonClassType);
  3534     if (result == NULL) {
  3535       report_out_of_shared_space(read_only ? SharedReadOnly : SharedReadWrite);
  3537     if (PrintSharedSpaces) {
  3538       space->record_allocation(result, type, space->vsm()->get_raw_word_size(word_size));
  3541     // Zero initialize.
  3542     Copy::fill_to_aligned_words((HeapWord*)result, word_size, 0);
  3544     return result;
  3547   MetadataType mdtype = (type == MetaspaceObj::ClassType) ? ClassType : NonClassType;
  3549   // Try to allocate metadata.
  3550   MetaWord* result = loader_data->metaspace_non_null()->allocate(word_size, mdtype);
  3552   if (result == NULL) {
  3553     tracer()->report_metaspace_allocation_failure(loader_data, word_size, type, mdtype);
  3555     // Allocation failed.
  3556     if (is_init_completed()) {
  3557       // Only start a GC if the bootstrapping has completed.
  3559       // Try to clean out some memory and retry.
  3560       result = Universe::heap()->collector_policy()->satisfy_failed_metadata_allocation(
  3561           loader_data, word_size, mdtype);
  3565   if (result == NULL) {
  3566     report_metadata_oome(loader_data, word_size, type, mdtype, CHECK_NULL);
  3569   // Zero initialize.
  3570   Copy::fill_to_aligned_words((HeapWord*)result, word_size, 0);
  3572   return result;
  3575 size_t Metaspace::class_chunk_size(size_t word_size) {
  3576   assert(using_class_space(), "Has to use class space");
  3577   return class_vsm()->calc_chunk_size(word_size);
  3580 void Metaspace::report_metadata_oome(ClassLoaderData* loader_data, size_t word_size, MetaspaceObj::Type type, MetadataType mdtype, TRAPS) {
  3581   tracer()->report_metadata_oom(loader_data, word_size, type, mdtype);
  3583   // If result is still null, we are out of memory.
  3584   if (Verbose && TraceMetadataChunkAllocation) {
  3585     gclog_or_tty->print_cr("Metaspace allocation failed for size "
  3586         SIZE_FORMAT, word_size);
  3587     if (loader_data->metaspace_or_null() != NULL) {
  3588       loader_data->dump(gclog_or_tty);
  3590     MetaspaceAux::dump(gclog_or_tty);
  3593   bool out_of_compressed_class_space = false;
  3594   if (is_class_space_allocation(mdtype)) {
  3595     Metaspace* metaspace = loader_data->metaspace_non_null();
  3596     out_of_compressed_class_space =
  3597       MetaspaceAux::committed_bytes(Metaspace::ClassType) +
  3598       (metaspace->class_chunk_size(word_size) * BytesPerWord) >
  3599       CompressedClassSpaceSize;
  3602   // -XX:+HeapDumpOnOutOfMemoryError and -XX:OnOutOfMemoryError support
  3603   const char* space_string = out_of_compressed_class_space ?
  3604     "Compressed class space" : "Metaspace";
  3606   report_java_out_of_memory(space_string);
  3608   if (JvmtiExport::should_post_resource_exhausted()) {
  3609     JvmtiExport::post_resource_exhausted(
  3610         JVMTI_RESOURCE_EXHAUSTED_OOM_ERROR,
  3611         space_string);
  3614   if (!is_init_completed()) {
  3615     vm_exit_during_initialization("OutOfMemoryError", space_string);
  3618   if (out_of_compressed_class_space) {
  3619     THROW_OOP(Universe::out_of_memory_error_class_metaspace());
  3620   } else {
  3621     THROW_OOP(Universe::out_of_memory_error_metaspace());
  3625 const char* Metaspace::metadata_type_name(Metaspace::MetadataType mdtype) {
  3626   switch (mdtype) {
  3627     case Metaspace::ClassType: return "Class";
  3628     case Metaspace::NonClassType: return "Metadata";
  3629     default:
  3630       assert(false, err_msg("Got bad mdtype: %d", (int) mdtype));
  3631       return NULL;
  3635 void Metaspace::record_allocation(void* ptr, MetaspaceObj::Type type, size_t word_size) {
  3636   assert(DumpSharedSpaces, "sanity");
  3638   int byte_size = (int)word_size * HeapWordSize;
  3639   AllocRecord *rec = new AllocRecord((address)ptr, type, byte_size);
  3641   if (_alloc_record_head == NULL) {
  3642     _alloc_record_head = _alloc_record_tail = rec;
  3643   } else if (_alloc_record_tail->_ptr + _alloc_record_tail->_byte_size == (address)ptr) {
  3644     _alloc_record_tail->_next = rec;
  3645     _alloc_record_tail = rec;
  3646   } else {
  3647     // slow linear search, but this doesn't happen that often, and only when dumping
  3648     for (AllocRecord *old = _alloc_record_head; old; old = old->_next) {
  3649       if (old->_ptr == ptr) {
  3650         assert(old->_type == MetaspaceObj::DeallocatedType, "sanity");
  3651         int remain_bytes = old->_byte_size - byte_size;
  3652         assert(remain_bytes >= 0, "sanity");
  3653         old->_type = type;
  3655         if (remain_bytes == 0) {
  3656           delete(rec);
  3657         } else {
  3658           address remain_ptr = address(ptr) + byte_size;
  3659           rec->_ptr = remain_ptr;
  3660           rec->_byte_size = remain_bytes;
  3661           rec->_type = MetaspaceObj::DeallocatedType;
  3662           rec->_next = old->_next;
  3663           old->_byte_size = byte_size;
  3664           old->_next = rec;
  3666         return;
  3669     assert(0, "reallocating a freed pointer that was not recorded");
  3673 void Metaspace::record_deallocation(void* ptr, size_t word_size) {
  3674   assert(DumpSharedSpaces, "sanity");
  3676   for (AllocRecord *rec = _alloc_record_head; rec; rec = rec->_next) {
  3677     if (rec->_ptr == ptr) {
  3678       assert(rec->_byte_size == (int)word_size * HeapWordSize, "sanity");
  3679       rec->_type = MetaspaceObj::DeallocatedType;
  3680       return;
  3684   assert(0, "deallocating a pointer that was not recorded");
  3687 void Metaspace::iterate(Metaspace::AllocRecordClosure *closure) {
  3688   assert(DumpSharedSpaces, "unimplemented for !DumpSharedSpaces");
  3690   address last_addr = (address)bottom();
  3692   for (AllocRecord *rec = _alloc_record_head; rec; rec = rec->_next) {
  3693     address ptr = rec->_ptr;
  3694     if (last_addr < ptr) {
  3695       closure->doit(last_addr, MetaspaceObj::UnknownType, ptr - last_addr);
  3697     closure->doit(ptr, rec->_type, rec->_byte_size);
  3698     last_addr = ptr + rec->_byte_size;
  3701   address top = ((address)bottom()) + used_bytes_slow(Metaspace::NonClassType);
  3702   if (last_addr < top) {
  3703     closure->doit(last_addr, MetaspaceObj::UnknownType, top - last_addr);
  3707 void Metaspace::purge(MetadataType mdtype) {
  3708   get_space_list(mdtype)->purge(get_chunk_manager(mdtype));
  3711 void Metaspace::purge() {
  3712   MutexLockerEx cl(SpaceManager::expand_lock(),
  3713                    Mutex::_no_safepoint_check_flag);
  3714   purge(NonClassType);
  3715   if (using_class_space()) {
  3716     purge(ClassType);
  3720 void Metaspace::print_on(outputStream* out) const {
  3721   // Print both class virtual space counts and metaspace.
  3722   if (Verbose) {
  3723     vsm()->print_on(out);
  3724     if (using_class_space()) {
  3725       class_vsm()->print_on(out);
  3730 bool Metaspace::contains(const void* ptr) {
  3731   if (UseSharedSpaces && MetaspaceShared::is_in_shared_space(ptr)) {
  3732     return true;
  3735   if (using_class_space() && get_space_list(ClassType)->contains(ptr)) {
  3736      return true;
  3739   return get_space_list(NonClassType)->contains(ptr);
  3742 void Metaspace::verify() {
  3743   vsm()->verify();
  3744   if (using_class_space()) {
  3745     class_vsm()->verify();
  3749 void Metaspace::dump(outputStream* const out) const {
  3750   out->print_cr("\nVirtual space manager: " INTPTR_FORMAT, vsm());
  3751   vsm()->dump(out);
  3752   if (using_class_space()) {
  3753     out->print_cr("\nClass space manager: " INTPTR_FORMAT, class_vsm());
  3754     class_vsm()->dump(out);
  3758 /////////////// Unit tests ///////////////
  3760 #ifndef PRODUCT
  3762 class TestMetaspaceAuxTest : AllStatic {
  3763  public:
  3764   static void test_reserved() {
  3765     size_t reserved = MetaspaceAux::reserved_bytes();
  3767     assert(reserved > 0, "assert");
  3769     size_t committed  = MetaspaceAux::committed_bytes();
  3770     assert(committed <= reserved, "assert");
  3772     size_t reserved_metadata = MetaspaceAux::reserved_bytes(Metaspace::NonClassType);
  3773     assert(reserved_metadata > 0, "assert");
  3774     assert(reserved_metadata <= reserved, "assert");
  3776     if (UseCompressedClassPointers) {
  3777       size_t reserved_class    = MetaspaceAux::reserved_bytes(Metaspace::ClassType);
  3778       assert(reserved_class > 0, "assert");
  3779       assert(reserved_class < reserved, "assert");
  3783   static void test_committed() {
  3784     size_t committed = MetaspaceAux::committed_bytes();
  3786     assert(committed > 0, "assert");
  3788     size_t reserved  = MetaspaceAux::reserved_bytes();
  3789     assert(committed <= reserved, "assert");
  3791     size_t committed_metadata = MetaspaceAux::committed_bytes(Metaspace::NonClassType);
  3792     assert(committed_metadata > 0, "assert");
  3793     assert(committed_metadata <= committed, "assert");
  3795     if (UseCompressedClassPointers) {
  3796       size_t committed_class    = MetaspaceAux::committed_bytes(Metaspace::ClassType);
  3797       assert(committed_class > 0, "assert");
  3798       assert(committed_class < committed, "assert");
  3802   static void test_virtual_space_list_large_chunk() {
  3803     VirtualSpaceList* vs_list = new VirtualSpaceList(os::vm_allocation_granularity());
  3804     MutexLockerEx cl(SpaceManager::expand_lock(), Mutex::_no_safepoint_check_flag);
  3805     // A size larger than VirtualSpaceSize (256k) and add one page to make it _not_ be
  3806     // vm_allocation_granularity aligned on Windows.
  3807     size_t large_size = (size_t)(2*256*K + (os::vm_page_size()/BytesPerWord));
  3808     large_size += (os::vm_page_size()/BytesPerWord);
  3809     vs_list->get_new_chunk(large_size, 0);
  3812   static void test() {
  3813     test_reserved();
  3814     test_committed();
  3815     test_virtual_space_list_large_chunk();
  3817 };
  3819 void TestMetaspaceAux_test() {
  3820   TestMetaspaceAuxTest::test();
  3823 class TestVirtualSpaceNodeTest {
  3824   static void chunk_up(size_t words_left, size_t& num_medium_chunks,
  3825                                           size_t& num_small_chunks,
  3826                                           size_t& num_specialized_chunks) {
  3827     num_medium_chunks = words_left / MediumChunk;
  3828     words_left = words_left % MediumChunk;
  3830     num_small_chunks = words_left / SmallChunk;
  3831     words_left = words_left % SmallChunk;
  3832     // how many specialized chunks can we get?
  3833     num_specialized_chunks = words_left / SpecializedChunk;
  3834     assert(words_left % SpecializedChunk == 0, "should be nothing left");
  3837  public:
  3838   static void test() {
  3839     MutexLockerEx ml(SpaceManager::expand_lock(), Mutex::_no_safepoint_check_flag);
  3840     const size_t vsn_test_size_words = MediumChunk  * 4;
  3841     const size_t vsn_test_size_bytes = vsn_test_size_words * BytesPerWord;
  3843     // The chunk sizes must be multiples of eachother, or this will fail
  3844     STATIC_ASSERT(MediumChunk % SmallChunk == 0);
  3845     STATIC_ASSERT(SmallChunk % SpecializedChunk == 0);
  3847     { // No committed memory in VSN
  3848       ChunkManager cm(SpecializedChunk, SmallChunk, MediumChunk);
  3849       VirtualSpaceNode vsn(vsn_test_size_bytes);
  3850       vsn.initialize();
  3851       vsn.retire(&cm);
  3852       assert(cm.sum_free_chunks_count() == 0, "did not commit any memory in the VSN");
  3855     { // All of VSN is committed, half is used by chunks
  3856       ChunkManager cm(SpecializedChunk, SmallChunk, MediumChunk);
  3857       VirtualSpaceNode vsn(vsn_test_size_bytes);
  3858       vsn.initialize();
  3859       vsn.expand_by(vsn_test_size_words, vsn_test_size_words);
  3860       vsn.get_chunk_vs(MediumChunk);
  3861       vsn.get_chunk_vs(MediumChunk);
  3862       vsn.retire(&cm);
  3863       assert(cm.sum_free_chunks_count() == 2, "should have been memory left for 2 medium chunks");
  3864       assert(cm.sum_free_chunks() == 2*MediumChunk, "sizes should add up");
  3867     { // 4 pages of VSN is committed, some is used by chunks
  3868       ChunkManager cm(SpecializedChunk, SmallChunk, MediumChunk);
  3869       VirtualSpaceNode vsn(vsn_test_size_bytes);
  3870       const size_t page_chunks = 4 * (size_t)os::vm_page_size() / BytesPerWord;
  3871       assert(page_chunks < MediumChunk, "Test expects medium chunks to be at least 4*page_size");
  3872       vsn.initialize();
  3873       vsn.expand_by(page_chunks, page_chunks);
  3874       vsn.get_chunk_vs(SmallChunk);
  3875       vsn.get_chunk_vs(SpecializedChunk);
  3876       vsn.retire(&cm);
  3878       // committed - used = words left to retire
  3879       const size_t words_left = page_chunks - SmallChunk - SpecializedChunk;
  3881       size_t num_medium_chunks, num_small_chunks, num_spec_chunks;
  3882       chunk_up(words_left, num_medium_chunks, num_small_chunks, num_spec_chunks);
  3884       assert(num_medium_chunks == 0, "should not get any medium chunks");
  3885       assert(cm.sum_free_chunks_count() == (num_small_chunks + num_spec_chunks), "should be space for 3 chunks");
  3886       assert(cm.sum_free_chunks() == words_left, "sizes should add up");
  3889     { // Half of VSN is committed, a humongous chunk is used
  3890       ChunkManager cm(SpecializedChunk, SmallChunk, MediumChunk);
  3891       VirtualSpaceNode vsn(vsn_test_size_bytes);
  3892       vsn.initialize();
  3893       vsn.expand_by(MediumChunk * 2, MediumChunk * 2);
  3894       vsn.get_chunk_vs(MediumChunk + SpecializedChunk); // Humongous chunks will be aligned up to MediumChunk + SpecializedChunk
  3895       vsn.retire(&cm);
  3897       const size_t words_left = MediumChunk * 2 - (MediumChunk + SpecializedChunk);
  3898       size_t num_medium_chunks, num_small_chunks, num_spec_chunks;
  3899       chunk_up(words_left, num_medium_chunks, num_small_chunks, num_spec_chunks);
  3901       assert(num_medium_chunks == 0, "should not get any medium chunks");
  3902       assert(cm.sum_free_chunks_count() == (num_small_chunks + num_spec_chunks), "should be space for 3 chunks");
  3903       assert(cm.sum_free_chunks() == words_left, "sizes should add up");
  3908 #define assert_is_available_positive(word_size) \
  3909   assert(vsn.is_available(word_size), \
  3910     err_msg(#word_size ": " PTR_FORMAT " bytes were not available in " \
  3911             "VirtualSpaceNode [" PTR_FORMAT ", " PTR_FORMAT ")", \
  3912             (uintptr_t)(word_size * BytesPerWord), vsn.bottom(), vsn.end()));
  3914 #define assert_is_available_negative(word_size) \
  3915   assert(!vsn.is_available(word_size), \
  3916     err_msg(#word_size ": " PTR_FORMAT " bytes should not be available in " \
  3917             "VirtualSpaceNode [" PTR_FORMAT ", " PTR_FORMAT ")", \
  3918             (uintptr_t)(word_size * BytesPerWord), vsn.bottom(), vsn.end()));
  3920   static void test_is_available_positive() {
  3921     // Reserve some memory.
  3922     VirtualSpaceNode vsn(os::vm_allocation_granularity());
  3923     assert(vsn.initialize(), "Failed to setup VirtualSpaceNode");
  3925     // Commit some memory.
  3926     size_t commit_word_size = os::vm_allocation_granularity() / BytesPerWord;
  3927     bool expanded = vsn.expand_by(commit_word_size, commit_word_size);
  3928     assert(expanded, "Failed to commit");
  3930     // Check that is_available accepts the committed size.
  3931     assert_is_available_positive(commit_word_size);
  3933     // Check that is_available accepts half the committed size.
  3934     size_t expand_word_size = commit_word_size / 2;
  3935     assert_is_available_positive(expand_word_size);
  3938   static void test_is_available_negative() {
  3939     // Reserve some memory.
  3940     VirtualSpaceNode vsn(os::vm_allocation_granularity());
  3941     assert(vsn.initialize(), "Failed to setup VirtualSpaceNode");
  3943     // Commit some memory.
  3944     size_t commit_word_size = os::vm_allocation_granularity() / BytesPerWord;
  3945     bool expanded = vsn.expand_by(commit_word_size, commit_word_size);
  3946     assert(expanded, "Failed to commit");
  3948     // Check that is_available doesn't accept a too large size.
  3949     size_t two_times_commit_word_size = commit_word_size * 2;
  3950     assert_is_available_negative(two_times_commit_word_size);
  3953   static void test_is_available_overflow() {
  3954     // Reserve some memory.
  3955     VirtualSpaceNode vsn(os::vm_allocation_granularity());
  3956     assert(vsn.initialize(), "Failed to setup VirtualSpaceNode");
  3958     // Commit some memory.
  3959     size_t commit_word_size = os::vm_allocation_granularity() / BytesPerWord;
  3960     bool expanded = vsn.expand_by(commit_word_size, commit_word_size);
  3961     assert(expanded, "Failed to commit");
  3963     // Calculate a size that will overflow the virtual space size.
  3964     void* virtual_space_max = (void*)(uintptr_t)-1;
  3965     size_t bottom_to_max = pointer_delta(virtual_space_max, vsn.bottom(), 1);
  3966     size_t overflow_size = bottom_to_max + BytesPerWord;
  3967     size_t overflow_word_size = overflow_size / BytesPerWord;
  3969     // Check that is_available can handle the overflow.
  3970     assert_is_available_negative(overflow_word_size);
  3973   static void test_is_available() {
  3974     TestVirtualSpaceNodeTest::test_is_available_positive();
  3975     TestVirtualSpaceNodeTest::test_is_available_negative();
  3976     TestVirtualSpaceNodeTest::test_is_available_overflow();
  3978 };
  3980 void TestVirtualSpaceNode_test() {
  3981   TestVirtualSpaceNodeTest::test();
  3982   TestVirtualSpaceNodeTest::test_is_available();
  3985 // The following test is placed here instead of a gtest / unittest file
  3986 // because the ChunkManager class is only available in this file.
  3987 class SpaceManagerTest : AllStatic {
  3988   friend void SpaceManager_test_adjust_initial_chunk_size();
  3990   static void test_adjust_initial_chunk_size(bool is_class) {
  3991     const size_t smallest = SpaceManager::smallest_chunk_size(is_class);
  3992     const size_t normal   = SpaceManager::small_chunk_size(is_class);
  3993     const size_t medium   = SpaceManager::medium_chunk_size(is_class);
  3995 #define test_adjust_initial_chunk_size(value, expected, is_class_value)          \
  3996     do {                                                                         \
  3997       size_t v = value;                                                          \
  3998       size_t e = expected;                                                       \
  3999       assert(SpaceManager::adjust_initial_chunk_size(v, (is_class_value)) == e,  \
  4000              err_msg("Expected: " SIZE_FORMAT " got: " SIZE_FORMAT, e, v));      \
  4001     } while (0)
  4003     // Smallest (specialized)
  4004     test_adjust_initial_chunk_size(1,            smallest, is_class);
  4005     test_adjust_initial_chunk_size(smallest - 1, smallest, is_class);
  4006     test_adjust_initial_chunk_size(smallest,     smallest, is_class);
  4008     // Small
  4009     test_adjust_initial_chunk_size(smallest + 1, normal, is_class);
  4010     test_adjust_initial_chunk_size(normal - 1,   normal, is_class);
  4011     test_adjust_initial_chunk_size(normal,       normal, is_class);
  4013     // Medium
  4014     test_adjust_initial_chunk_size(normal + 1, medium, is_class);
  4015     test_adjust_initial_chunk_size(medium - 1, medium, is_class);
  4016     test_adjust_initial_chunk_size(medium,     medium, is_class);
  4018     // Humongous
  4019     test_adjust_initial_chunk_size(medium + 1, medium + 1, is_class);
  4021 #undef test_adjust_initial_chunk_size
  4024   static void test_adjust_initial_chunk_size() {
  4025     test_adjust_initial_chunk_size(false);
  4026     test_adjust_initial_chunk_size(true);
  4028 };
  4030 void SpaceManager_test_adjust_initial_chunk_size() {
  4031   SpaceManagerTest::test_adjust_initial_chunk_size();
  4034 // The following test is placed here instead of a gtest / unittest file
  4035 // because the ChunkManager class is only available in this file.
  4036 void ChunkManager_test_list_index() {
  4037   ChunkManager manager(ClassSpecializedChunk, ClassSmallChunk, ClassMediumChunk);
  4039   // Test previous bug where a query for a humongous class metachunk,
  4040   // incorrectly matched the non-class medium metachunk size.
  4042     assert(MediumChunk > ClassMediumChunk, "Precondition for test");
  4044     ChunkIndex index = manager.list_index(MediumChunk);
  4046     assert(index == HumongousIndex,
  4047            err_msg("Requested size is larger than ClassMediumChunk,"
  4048            " so should return HumongousIndex. Got index: %d", (int)index));
  4051   // Check the specified sizes as well.
  4053     ChunkIndex index = manager.list_index(ClassSpecializedChunk);
  4054     assert(index == SpecializedIndex, err_msg("Wrong index returned. Got index: %d", (int)index));
  4057     ChunkIndex index = manager.list_index(ClassSmallChunk);
  4058     assert(index == SmallIndex, err_msg("Wrong index returned. Got index: %d", (int)index));
  4061     ChunkIndex index = manager.list_index(ClassMediumChunk);
  4062     assert(index == MediumIndex, err_msg("Wrong index returned. Got index: %d", (int)index));
  4065     ChunkIndex index = manager.list_index(ClassMediumChunk + 1);
  4066     assert(index == HumongousIndex, err_msg("Wrong index returned. Got index: %d", (int)index));
  4070 #endif

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