jdk8-mips64-public/hotspot: src/share/vm/memory/metaspace.cpp@601183f604b2 (annotated)

src/share/vm/memory/metaspace.cpp@601183f604b2 (annotated)

src/share/vm/memory/metaspace.cpp

Mon, 29 Apr 2013 13:07:27 +0200

author: mgerdin
date: Mon, 29 Apr 2013 13:07:27 +0200
changeset 5023: 601183f604b2
parent 5015: 868d87ed63c8
child 5162: 2b1a9d972fc2
permissions: -rw-r--r--

8013129: Possible deadlock with Metaspace locks due to mixed usage of safepoint aware and non-safepoint aware locking
Summary: Change Metaspace::deallocate to take lock with _no_safepoint_check_flag
Reviewed-by: coleenp, jmasa, dholmes

 /*
  * Copyright (c) 2011, 2013, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
  * under the terms of the GNU General Public License version 2 only, as
  * published by the Free Software Foundation.
  *
  * This code is distributed in the hope that it will be useful, but WITHOUT
  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  * version 2 for more details (a copy is included in the LICENSE file that
  * accompanied this code).
  *
  * You should have received a copy of the GNU General Public License version
  * 2 along with this work; if not, write to the Free Software Foundation,
  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  *
  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  * or visit www.oracle.com if you need additional information or have any
  * questions.
  *
  */
 #include "precompiled.hpp"
 #include "gc_interface/collectedHeap.hpp"
 #include "memory/binaryTreeDictionary.hpp"
 #include "memory/freeList.hpp"
 #include "memory/collectorPolicy.hpp"
 #include "memory/filemap.hpp"
 #include "memory/freeList.hpp"
 #include "memory/metablock.hpp"
 #include "memory/metachunk.hpp"
 #include "memory/metaspace.hpp"
 #include "memory/metaspaceShared.hpp"
 #include "memory/resourceArea.hpp"
 #include "memory/universe.hpp"
 #include "runtime/globals.hpp"
 #include "runtime/mutex.hpp"
 #include "runtime/orderAccess.hpp"
 #include "services/memTracker.hpp"
 #include "utilities/copy.hpp"
 #include "utilities/debug.hpp"
 typedef BinaryTreeDictionary<Metablock, FreeList> BlockTreeDictionary;
 typedef BinaryTreeDictionary<Metachunk, FreeList> ChunkTreeDictionary;
 // Define this macro to enable slow integrity checking of
 // the free chunk lists
 const bool metaspace_slow_verify = false;
 // Parameters for stress mode testing
 const uint metadata_deallocate_a_lot_block = 10;
 const uint metadata_deallocate_a_lock_chunk = 3;
 size_t const allocation_from_dictionary_limit = 64 * K;
 MetaWord* last_allocated = 0;
 // Used in declarations in SpaceManager and ChunkManager
 enum ChunkIndex {
   ZeroIndex = 0,
   SpecializedIndex = ZeroIndex,
   SmallIndex = SpecializedIndex + 1,
   MediumIndex = SmallIndex + 1,
   HumongousIndex = MediumIndex + 1,
   NumberOfFreeLists = 3,
   NumberOfInUseLists = 4
 };
 enum ChunkSizes {    // in words.
   ClassSpecializedChunk = 128,
   SpecializedChunk = 128,
   ClassSmallChunk = 256,
   SmallChunk = 512,
   ClassMediumChunk = 1 * K,
   MediumChunk = 8 * K,
   HumongousChunkGranularity = 8
 };
 static ChunkIndex next_chunk_index(ChunkIndex i) {
   assert(i < NumberOfInUseLists, "Out of bound");
   return (ChunkIndex) (i+1);
 }
 // Originally _capacity_until_GC was set to MetaspaceSize here but
 // the default MetaspaceSize before argument processing was being
 // used which was not the desired value.  See the code
 // in should_expand() to see how the initialization is handled
 // now.
 size_t MetaspaceGC::_capacity_until_GC = 0;
 bool MetaspaceGC::_expand_after_GC = false;
 uint MetaspaceGC::_shrink_factor = 0;
 bool MetaspaceGC::_should_concurrent_collect = false;
 // Blocks of space for metadata are allocated out of Metachunks.
 //
 // Metachunk are allocated out of MetadataVirtualspaces and once
 // allocated there is no explicit link between a Metachunk and
 // the MetadataVirtualspaces from which it was allocated.
 //
 // Each SpaceManager maintains a
 // list of the chunks it is using and the current chunk.  The current
 // chunk is the chunk from which allocations are done.  Space freed in
 // a chunk is placed on the free list of blocks (BlockFreelist) and
 // reused from there.
 typedef class FreeList<Metachunk> ChunkList;
 // Manages the global free lists of chunks.
 // Has three lists of free chunks, and a total size and
 // count that includes all three
 class ChunkManager VALUE_OBJ_CLASS_SPEC {
   // Free list of chunks of different sizes.
   //   SpecializedChunk
   //   SmallChunk
   //   MediumChunk
   //   HumongousChunk
   ChunkList _free_chunks[NumberOfFreeLists];
   //   HumongousChunk
   ChunkTreeDictionary _humongous_dictionary;
   // ChunkManager in all lists of this type
   size_t _free_chunks_total;
   size_t _free_chunks_count;
   void dec_free_chunks_total(size_t v) {
     assert(_free_chunks_count > 0 &&
              _free_chunks_total > 0,
              "About to go negative");
     Atomic::add_ptr(-1, &_free_chunks_count);
     jlong minus_v = (jlong) - (jlong) v;
     Atomic::add_ptr(minus_v, &_free_chunks_total);
   }
   // Debug support
   size_t sum_free_chunks();
   size_t sum_free_chunks_count();
   void locked_verify_free_chunks_total();
   void slow_locked_verify_free_chunks_total() {
     if (metaspace_slow_verify) {
       locked_verify_free_chunks_total();
     }
   }
   void locked_verify_free_chunks_count();
   void slow_locked_verify_free_chunks_count() {
     if (metaspace_slow_verify) {
       locked_verify_free_chunks_count();
     }
   }
   void verify_free_chunks_count();
  public:
   ChunkManager() : _free_chunks_total(0), _free_chunks_count(0) {}
   // add or delete (return) a chunk to the global freelist.
   Metachunk* chunk_freelist_allocate(size_t word_size);
   void chunk_freelist_deallocate(Metachunk* chunk);
   // Map a size to a list index assuming that there are lists
   // for special, small, medium, and humongous chunks.
   static ChunkIndex list_index(size_t size);
   // Remove the chunk from its freelist.  It is
   // expected to be on one of the _free_chunks[] lists.
   void remove_chunk(Metachunk* chunk);
   // Add the simple linked list of chunks to the freelist of chunks
   // of type index.
   void return_chunks(ChunkIndex index, Metachunk* chunks);
   // Total of the space in the free chunks list
   size_t free_chunks_total();
   size_t free_chunks_total_in_bytes();
   // Number of chunks in the free chunks list
   size_t free_chunks_count();
   void inc_free_chunks_total(size_t v, size_t count = 1) {
     Atomic::add_ptr(count, &_free_chunks_count);
     Atomic::add_ptr(v, &_free_chunks_total);
   }
   ChunkTreeDictionary* humongous_dictionary() {
     return &_humongous_dictionary;
   }
   ChunkList* free_chunks(ChunkIndex index);
   // Returns the list for the given chunk word size.
   ChunkList* find_free_chunks_list(size_t word_size);
   // Add and remove from a list by size.  Selects
   // list based on size of chunk.
   void free_chunks_put(Metachunk* chuck);
   Metachunk* free_chunks_get(size_t chunk_word_size);
   // Debug support
   void verify();
   void slow_verify() {
     if (metaspace_slow_verify) {
       verify();
     }
   }
   void locked_verify();
   void slow_locked_verify() {
     if (metaspace_slow_verify) {
       locked_verify();
     }
   }
   void verify_free_chunks_total();
   void locked_print_free_chunks(outputStream* st);
   void locked_print_sum_free_chunks(outputStream* st);
   void print_on(outputStream* st);
 };
 // Used to manage the free list of Metablocks (a block corresponds
 // to the allocation of a quantum of metadata).
 class BlockFreelist VALUE_OBJ_CLASS_SPEC {
   BlockTreeDictionary* _dictionary;
   static Metablock* initialize_free_chunk(MetaWord* p, size_t word_size);
   // Accessors
   BlockTreeDictionary* dictionary() const { return _dictionary; }
  public:
   BlockFreelist();
   ~BlockFreelist();
   // Get and return a block to the free list
   MetaWord* get_block(size_t word_size);
   void return_block(MetaWord* p, size_t word_size);
   size_t total_size() {
   if (dictionary() == NULL) {
     return 0;
   } else {
     return dictionary()->total_size();
   }
 }
   void print_on(outputStream* st) const;
 };
 class VirtualSpaceNode : public CHeapObj<mtClass> {
   friend class VirtualSpaceList;
   // Link to next VirtualSpaceNode
   VirtualSpaceNode* _next;
   // total in the VirtualSpace
   MemRegion _reserved;
   ReservedSpace _rs;
   VirtualSpace _virtual_space;
   MetaWord* _top;
   // count of chunks contained in this VirtualSpace
   uintx _container_count;
   // Convenience functions for logical bottom and end
   MetaWord* bottom() const { return (MetaWord*) _virtual_space.low(); }
   MetaWord* end() const { return (MetaWord*) _virtual_space.high(); }
   // Convenience functions to access the _virtual_space
   char* low()  const { return virtual_space()->low(); }
   char* high() const { return virtual_space()->high(); }
   // The first Metachunk will be allocated at the bottom of the
   // VirtualSpace
   Metachunk* first_chunk() { return (Metachunk*) bottom(); }
   void inc_container_count();
 #ifdef ASSERT
   uint container_count_slow();
 #endif
  public:
   VirtualSpaceNode(size_t byte_size);
   VirtualSpaceNode(ReservedSpace rs) : _top(NULL), _next(NULL), _rs(rs), _container_count(0) {}
   ~VirtualSpaceNode();
   // address of next available space in _virtual_space;
   // Accessors
   VirtualSpaceNode* next() { return _next; }
   void set_next(VirtualSpaceNode* v) { _next = v; }
   void set_reserved(MemRegion const v) { _reserved = v; }
   void set_top(MetaWord* v) { _top = v; }
   // Accessors
   MemRegion* reserved() { return &_reserved; }
   VirtualSpace* virtual_space() const { return (VirtualSpace*) &_virtual_space; }
   // Returns true if "word_size" is available in the VirtualSpace
   bool is_available(size_t word_size) { return _top + word_size <= end(); }
   MetaWord* top() const { return _top; }
   void inc_top(size_t word_size) { _top += word_size; }
   uintx container_count() { return _container_count; }
   void dec_container_count();
 #ifdef ASSERT
   void verify_container_count();
 #endif
   // used and capacity in this single entry in the list
   size_t used_words_in_vs() const;
   size_t capacity_words_in_vs() const;
   size_t free_words_in_vs() const;
   bool initialize();
   // get space from the virtual space
   Metachunk* take_from_committed(size_t chunk_word_size);
   // Allocate a chunk from the virtual space and return it.
   Metachunk* get_chunk_vs(size_t chunk_word_size);
   Metachunk* get_chunk_vs_with_expand(size_t chunk_word_size);
   // Expands/shrinks the committed space in a virtual space.  Delegates
   // to Virtualspace
   bool expand_by(size_t words, bool pre_touch = false);
   bool shrink_by(size_t words);
   // In preparation for deleting this node, remove all the chunks
   // in the node from any freelist.
   void purge(ChunkManager* chunk_manager);
 #ifdef ASSERT
   // Debug support
   static void verify_virtual_space_total();
   static void verify_virtual_space_count();
   void mangle();
 #endif
   void print_on(outputStream* st) const;
 };
   // byte_size is the size of the associated virtualspace.
 VirtualSpaceNode::VirtualSpaceNode(size_t byte_size) : _top(NULL), _next(NULL), _rs(0), _container_count(0) {
   // align up to vm allocation granularity
   byte_size = align_size_up(byte_size, os::vm_allocation_granularity());
   // This allocates memory with mmap.  For DumpSharedspaces, try to reserve
   // configurable address, generally at the top of the Java heap so other
   // memory addresses don't conflict.
   if (DumpSharedSpaces) {
     char* shared_base = (char*)SharedBaseAddress;
     _rs = ReservedSpace(byte_size, 0, false, shared_base, 0);
     if (_rs.is_reserved()) {
       assert(shared_base == 0 || _rs.base() == shared_base, "should match");
     } else {
       // Get a mmap region anywhere if the SharedBaseAddress fails.
       _rs = ReservedSpace(byte_size);
     }
     MetaspaceShared::set_shared_rs(&_rs);
   } else {
     _rs = ReservedSpace(byte_size);
   }
   MemTracker::record_virtual_memory_type((address)_rs.base(), mtClass);
 }
 void VirtualSpaceNode::purge(ChunkManager* chunk_manager) {
   Metachunk* chunk = first_chunk();
   Metachunk* invalid_chunk = (Metachunk*) top();
   while (chunk < invalid_chunk ) {
     assert(chunk->is_free(), "Should be marked free");
       MetaWord* next = ((MetaWord*)chunk) + chunk->word_size();
       chunk_manager->remove_chunk(chunk);
       assert(chunk->next() == NULL &&
              chunk->prev() == NULL,
              "Was not removed from its list");
       chunk = (Metachunk*) next;
   }
 }
 #ifdef ASSERT
 uint VirtualSpaceNode::container_count_slow() {
   uint count = 0;
   Metachunk* chunk = first_chunk();
   Metachunk* invalid_chunk = (Metachunk*) top();
   while (chunk < invalid_chunk ) {
     MetaWord* next = ((MetaWord*)chunk) + chunk->word_size();
     // Don't count the chunks on the free lists.  Those are
     // still part of the VirtualSpaceNode but not currently
     // counted.
     if (!chunk->is_free()) {
       count++;
     }
     chunk = (Metachunk*) next;
   }
   return count;
 }
 #endif
 // List of VirtualSpaces for metadata allocation.
 // It has a  _next link for singly linked list and a MemRegion
 // for total space in the VirtualSpace.
 class VirtualSpaceList : public CHeapObj<mtClass> {
   friend class VirtualSpaceNode;
   enum VirtualSpaceSizes {
     VirtualSpaceSize = 256 * K
   };
   // Global list of virtual spaces
   // Head of the list
   VirtualSpaceNode* _virtual_space_list;
   // virtual space currently being used for allocations
   VirtualSpaceNode* _current_virtual_space;
   // Free chunk list for all other metadata
   ChunkManager      _chunk_manager;
   // Can this virtual list allocate >1 spaces?  Also, used to determine
   // whether to allocate unlimited small chunks in this virtual space
   bool _is_class;
   bool can_grow() const { return !is_class() || !UseCompressedKlassPointers; }
   // Sum of space in all virtual spaces and number of virtual spaces
   size_t _virtual_space_total;
   size_t _virtual_space_count;
   ~VirtualSpaceList();
   VirtualSpaceNode* virtual_space_list() const { return _virtual_space_list; }
   void set_virtual_space_list(VirtualSpaceNode* v) {
     _virtual_space_list = v;
   }
   void set_current_virtual_space(VirtualSpaceNode* v) {
     _current_virtual_space = v;
   }
   void link_vs(VirtualSpaceNode* new_entry, size_t vs_word_size);
   // Get another virtual space and add it to the list.  This
   // is typically prompted by a failed attempt to allocate a chunk
   // and is typically followed by the allocation of a chunk.
   bool grow_vs(size_t vs_word_size);
  public:
   VirtualSpaceList(size_t word_size);
   VirtualSpaceList(ReservedSpace rs);
   size_t free_bytes();
   Metachunk* get_new_chunk(size_t word_size,
                            size_t grow_chunks_by_words,
                            size_t medium_chunk_bunch);
   // Get the first chunk for a Metaspace.  Used for
   // special cases such as the boot class loader, reflection
   // class loader and anonymous class loader.
   Metachunk* get_initialization_chunk(size_t word_size, size_t chunk_bunch);
   VirtualSpaceNode* current_virtual_space() {
     return _current_virtual_space;
   }
   ChunkManager* chunk_manager() { return &_chunk_manager; }
   bool is_class() const { return _is_class; }
   // Allocate the first virtualspace.
   void initialize(size_t word_size);
   size_t virtual_space_total() { return _virtual_space_total; }
   void inc_virtual_space_total(size_t v);
   void dec_virtual_space_total(size_t v);
   void inc_virtual_space_count();
   void dec_virtual_space_count();
   // Unlink empty VirtualSpaceNodes and free it.
   void purge();
   // Used and capacity in the entire list of virtual spaces.
   // These are global values shared by all Metaspaces
   size_t capacity_words_sum();
   size_t capacity_bytes_sum() { return capacity_words_sum() * BytesPerWord; }
   size_t used_words_sum();
   size_t used_bytes_sum() { return used_words_sum() * BytesPerWord; }
   bool contains(const void *ptr);
   void print_on(outputStream* st) const;
   class VirtualSpaceListIterator : public StackObj {
     VirtualSpaceNode* _virtual_spaces;
    public:
     VirtualSpaceListIterator(VirtualSpaceNode* virtual_spaces) :
       _virtual_spaces(virtual_spaces) {}
     bool repeat() {
       return _virtual_spaces != NULL;
     }
     VirtualSpaceNode* get_next() {
       VirtualSpaceNode* result = _virtual_spaces;
       if (_virtual_spaces != NULL) {
         _virtual_spaces = _virtual_spaces->next();
       }
       return result;
     }
   };
 };
 class Metadebug : AllStatic {
   // Debugging support for Metaspaces
   static int _deallocate_block_a_lot_count;
   static int _deallocate_chunk_a_lot_count;
   static int _allocation_fail_alot_count;
  public:
   static int deallocate_block_a_lot_count() {
     return _deallocate_block_a_lot_count;
   }
   static void set_deallocate_block_a_lot_count(int v) {
     _deallocate_block_a_lot_count = v;
   }
   static void inc_deallocate_block_a_lot_count() {
     _deallocate_block_a_lot_count++;
   }
   static int deallocate_chunk_a_lot_count() {
     return _deallocate_chunk_a_lot_count;
   }
   static void reset_deallocate_chunk_a_lot_count() {
     _deallocate_chunk_a_lot_count = 1;
   }
   static void inc_deallocate_chunk_a_lot_count() {
     _deallocate_chunk_a_lot_count++;
   }
   static void init_allocation_fail_alot_count();
 #ifdef ASSERT
   static bool test_metadata_failure();
 #endif
   static void deallocate_chunk_a_lot(SpaceManager* sm,
                                      size_t chunk_word_size);
   static void deallocate_block_a_lot(SpaceManager* sm,
                                      size_t chunk_word_size);
 };
 int Metadebug::_deallocate_block_a_lot_count = 0;
 int Metadebug::_deallocate_chunk_a_lot_count = 0;
 int Metadebug::_allocation_fail_alot_count = 0;
 //  SpaceManager - used by Metaspace to handle allocations
 class SpaceManager : public CHeapObj<mtClass> {
   friend class Metaspace;
   friend class Metadebug;
  private:
   // protects allocations and contains.
   Mutex* const _lock;
   // Chunk related size
   size_t _medium_chunk_bunch;
   // List of chunks in use by this SpaceManager.  Allocations
   // are done from the current chunk.  The list is used for deallocating
   // chunks when the SpaceManager is freed.
   Metachunk* _chunks_in_use[NumberOfInUseLists];
   Metachunk* _current_chunk;
   // Virtual space where allocation comes from.
   VirtualSpaceList* _vs_list;
   // Number of small chunks to allocate to a manager
   // If class space manager, small chunks are unlimited
   static uint const _small_chunk_limit;
   bool has_small_chunk_limit() { return !vs_list()->is_class(); }
   // Sum of all space in allocated chunks
   size_t _allocated_blocks_words;
   // Sum of all allocated chunks
   size_t _allocated_chunks_words;
   size_t _allocated_chunks_count;
   // Free lists of blocks are per SpaceManager since they
   // are assumed to be in chunks in use by the SpaceManager
   // and all chunks in use by a SpaceManager are freed when
   // the class loader using the SpaceManager is collected.
   BlockFreelist _block_freelists;
   // protects virtualspace and chunk expansions
   static const char*  _expand_lock_name;
   static const int    _expand_lock_rank;
   static Mutex* const _expand_lock;
  private:
   // Accessors
   Metachunk* chunks_in_use(ChunkIndex index) const { return _chunks_in_use[index]; }
   void set_chunks_in_use(ChunkIndex index, Metachunk* v) { _chunks_in_use[index] = v; }
   BlockFreelist* block_freelists() const {
     return (BlockFreelist*) &_block_freelists;
   }
   VirtualSpaceList* vs_list() const    { return _vs_list; }
   Metachunk* current_chunk() const { return _current_chunk; }
   void set_current_chunk(Metachunk* v) {
     _current_chunk = v;
   }
   Metachunk* find_current_chunk(size_t word_size);
   // Add chunk to the list of chunks in use
   void add_chunk(Metachunk* v, bool make_current);
   Mutex* lock() const { return _lock; }
   const char* chunk_size_name(ChunkIndex index) const;
  protected:
   void initialize();
  public:
   SpaceManager(Mutex* lock,
                VirtualSpaceList* vs_list);
   ~SpaceManager();
   enum ChunkMultiples {
     MediumChunkMultiple = 4
   };
   // Accessors
   size_t specialized_chunk_size() { return SpecializedChunk; }
   size_t small_chunk_size() { return (size_t) vs_list()->is_class() ? ClassSmallChunk : SmallChunk; }
   size_t medium_chunk_size() { return (size_t) vs_list()->is_class() ? ClassMediumChunk : MediumChunk; }
   size_t medium_chunk_bunch() { return medium_chunk_size() * MediumChunkMultiple; }
   size_t allocated_blocks_words() const { return _allocated_blocks_words; }
   size_t allocated_blocks_bytes() const { return _allocated_blocks_words * BytesPerWord; }
   size_t allocated_chunks_words() const { return _allocated_chunks_words; }
   size_t allocated_chunks_count() const { return _allocated_chunks_count; }
   bool is_humongous(size_t word_size) { return word_size > medium_chunk_size(); }
   static Mutex* expand_lock() { return _expand_lock; }
   // Increment the per Metaspace and global running sums for Metachunks
   // by the given size.  This is used when a Metachunk to added to
   // the in-use list.
   void inc_size_metrics(size_t words);
   // Increment the per Metaspace and global running sums Metablocks by the given
   // size.  This is used when a Metablock is allocated.
   void inc_used_metrics(size_t words);
   // Delete the portion of the running sums for this SpaceManager. That is,
   // the globals running sums for the Metachunks and Metablocks are
   // decremented for all the Metachunks in-use by this SpaceManager.
   void dec_total_from_size_metrics();
   // Set the sizes for the initial chunks.
   void get_initial_chunk_sizes(Metaspace::MetaspaceType type,
                                size_t* chunk_word_size,
                                size_t* class_chunk_word_size);
   size_t sum_capacity_in_chunks_in_use() const;
   size_t sum_used_in_chunks_in_use() const;
   size_t sum_free_in_chunks_in_use() const;
   size_t sum_waste_in_chunks_in_use() const;
   size_t sum_waste_in_chunks_in_use(ChunkIndex index ) const;
   size_t sum_count_in_chunks_in_use();
   size_t sum_count_in_chunks_in_use(ChunkIndex i);
   Metachunk* get_new_chunk(size_t word_size, size_t grow_chunks_by_words);
   // Block allocation and deallocation.
   // Allocates a block from the current chunk
   MetaWord* allocate(size_t word_size);
   // Helper for allocations
   MetaWord* allocate_work(size_t word_size);
   // Returns a block to the per manager freelist
   void deallocate(MetaWord* p, size_t word_size);
   // Based on the allocation size and a minimum chunk size,
   // returned chunk size (for expanding space for chunk allocation).
   size_t calc_chunk_size(size_t allocation_word_size);
   // Called when an allocation from the current chunk fails.
   // Gets a new chunk (may require getting a new virtual space),
   // and allocates from that chunk.
   MetaWord* grow_and_allocate(size_t word_size);
   // debugging support.
   void dump(outputStream* const out) const;
   void print_on(outputStream* st) const;
   void locked_print_chunks_in_use_on(outputStream* st) const;
   void verify();
   void verify_chunk_size(Metachunk* chunk);
   NOT_PRODUCT(void mangle_freed_chunks();)
 #ifdef ASSERT
   void verify_allocated_blocks_words();
 #endif
 };
 uint const SpaceManager::_small_chunk_limit = 4;
 const char* SpaceManager::_expand_lock_name =
   "SpaceManager chunk allocation lock";
 const int SpaceManager::_expand_lock_rank = Monitor::leaf - 1;
 Mutex* const SpaceManager::_expand_lock =
   new Mutex(SpaceManager::_expand_lock_rank,
             SpaceManager::_expand_lock_name,
             Mutex::_allow_vm_block_flag);
 void VirtualSpaceNode::inc_container_count() {
   assert_lock_strong(SpaceManager::expand_lock());
   _container_count++;
   assert(_container_count == container_count_slow(),
          err_msg("Inconsistency in countainer_count _container_count " SIZE_FORMAT
                  "container_count_slow() " SIZE_FORMAT,
                  _container_count, container_count_slow()));
 }
 void VirtualSpaceNode::dec_container_count() {
   assert_lock_strong(SpaceManager::expand_lock());
   _container_count--;
 }
 #ifdef ASSERT
 void VirtualSpaceNode::verify_container_count() {
   assert(_container_count == container_count_slow(),
     err_msg("Inconsistency in countainer_count _container_count " SIZE_FORMAT
             "container_count_slow() " SIZE_FORMAT, _container_count, container_count_slow()));
 }
 #endif
 // BlockFreelist methods
 BlockFreelist::BlockFreelist() : _dictionary(NULL) {}
 BlockFreelist::~BlockFreelist() {
   if (_dictionary != NULL) {
     if (Verbose && TraceMetadataChunkAllocation) {
       _dictionary->print_free_lists(gclog_or_tty);
     }
     delete _dictionary;
   }
 }
 Metablock* BlockFreelist::initialize_free_chunk(MetaWord* p, size_t word_size) {
   Metablock* block = (Metablock*) p;
   block->set_word_size(word_size);
   block->set_prev(NULL);
   block->set_next(NULL);
   return block;
 }
 void BlockFreelist::return_block(MetaWord* p, size_t word_size) {
   Metablock* free_chunk = initialize_free_chunk(p, word_size);
   if (dictionary() == NULL) {
    _dictionary = new BlockTreeDictionary();
   }
   dictionary()->return_chunk(free_chunk);
 }
 MetaWord* BlockFreelist::get_block(size_t word_size) {
   if (dictionary() == NULL) {
     return NULL;
   }
   if (word_size < TreeChunk<Metablock, FreeList>::min_size()) {
     // Dark matter.  Too small for dictionary.
     return NULL;
   }
   Metablock* free_block =
     dictionary()->get_chunk(word_size, FreeBlockDictionary<Metablock>::exactly);
   if (free_block == NULL) {
     return NULL;
   }
   return (MetaWord*) free_block;
 }
 void BlockFreelist::print_on(outputStream* st) const {
   if (dictionary() == NULL) {
     return;
   }
   dictionary()->print_free_lists(st);
 }
 // VirtualSpaceNode methods
 VirtualSpaceNode::~VirtualSpaceNode() {
   _rs.release();
 #ifdef ASSERT
   size_t word_size = sizeof(*this) / BytesPerWord;
   Copy::fill_to_words((HeapWord*) this, word_size, 0xf1f1f1f1);
 #endif
 }
 size_t VirtualSpaceNode::used_words_in_vs() const {
   return pointer_delta(top(), bottom(), sizeof(MetaWord));
 }
 // Space committed in the VirtualSpace
 size_t VirtualSpaceNode::capacity_words_in_vs() const {
   return pointer_delta(end(), bottom(), sizeof(MetaWord));
 }
 size_t VirtualSpaceNode::free_words_in_vs() const {
   return pointer_delta(end(), top(), sizeof(MetaWord));
 }
 // Allocates the chunk from the virtual space only.
 // This interface is also used internally for debugging.  Not all
 // chunks removed here are necessarily used for allocation.
 Metachunk* VirtualSpaceNode::take_from_committed(size_t chunk_word_size) {
   // Bottom of the new chunk
   MetaWord* chunk_limit = top();
   assert(chunk_limit != NULL, "Not safe to call this method");
   if (!is_available(chunk_word_size)) {
     if (TraceMetadataChunkAllocation) {
       tty->print("VirtualSpaceNode::take_from_committed() not available %d words ", chunk_word_size);
       // Dump some information about the virtual space that is nearly full
       print_on(tty);
     }
     return NULL;
   }
   // Take the space  (bump top on the current virtual space).
   inc_top(chunk_word_size);
   // Initialize the chunk
   Metachunk* result = ::new (chunk_limit) Metachunk(chunk_word_size, this);
   return result;
 }
 // Expand the virtual space (commit more of the reserved space)
 bool VirtualSpaceNode::expand_by(size_t words, bool pre_touch) {
   size_t bytes = words * BytesPerWord;
   bool result =  virtual_space()->expand_by(bytes, pre_touch);
   if (TraceMetavirtualspaceAllocation && !result) {
     gclog_or_tty->print_cr("VirtualSpaceNode::expand_by() failed "
                            "for byte size " SIZE_FORMAT, bytes);
     virtual_space()->print();
   }
   return result;
 }
 // Shrink the virtual space (commit more of the reserved space)
 bool VirtualSpaceNode::shrink_by(size_t words) {
   size_t bytes = words * BytesPerWord;
   virtual_space()->shrink_by(bytes);
   return true;
 }
 // Add another chunk to the chunk list.
 Metachunk* VirtualSpaceNode::get_chunk_vs(size_t chunk_word_size) {
   assert_lock_strong(SpaceManager::expand_lock());
   Metachunk* result = take_from_committed(chunk_word_size);
   if (result != NULL) {
     inc_container_count();
   }
   return result;
 }
 Metachunk* VirtualSpaceNode::get_chunk_vs_with_expand(size_t chunk_word_size) {
   assert_lock_strong(SpaceManager::expand_lock());
   Metachunk* new_chunk = get_chunk_vs(chunk_word_size);
   if (new_chunk == NULL) {
     // Only a small part of the virtualspace is committed when first
     // allocated so committing more here can be expected.
     size_t page_size_words = os::vm_page_size() / BytesPerWord;
     size_t aligned_expand_vs_by_words = align_size_up(chunk_word_size,
                                                     page_size_words);
     expand_by(aligned_expand_vs_by_words, false);
     new_chunk = get_chunk_vs(chunk_word_size);
   }
   return new_chunk;
 }
 bool VirtualSpaceNode::initialize() {
   if (!_rs.is_reserved()) {
     return false;
   }
   // An allocation out of this Virtualspace that is larger
   // than an initial commit size can waste that initial committed
   // space.
   size_t committed_byte_size = 0;
   bool result = virtual_space()->initialize(_rs, committed_byte_size);
   if (result) {
     set_top((MetaWord*)virtual_space()->low());
     set_reserved(MemRegion((HeapWord*)_rs.base(),
                  (HeapWord*)(_rs.base() + _rs.size())));
     assert(reserved()->start() == (HeapWord*) _rs.base(),
       err_msg("Reserved start was not set properly " PTR_FORMAT
         " != " PTR_FORMAT, reserved()->start(), _rs.base()));
     assert(reserved()->word_size() == _rs.size() / BytesPerWord,
       err_msg("Reserved size was not set properly " SIZE_FORMAT
         " != " SIZE_FORMAT, reserved()->word_size(),
         _rs.size() / BytesPerWord));
   }
   return result;
 }
 void VirtualSpaceNode::print_on(outputStream* st) const {
   size_t used = used_words_in_vs();
   size_t capacity = capacity_words_in_vs();
   VirtualSpace* vs = virtual_space();
   st->print_cr("   space @ " PTR_FORMAT " " SIZE_FORMAT "K, %3d%% used "
            "[" PTR_FORMAT ", " PTR_FORMAT ", "
            PTR_FORMAT ", " PTR_FORMAT ")",
            vs, capacity / K,
            capacity == 0 ? 0 : used * 100 / capacity,
            bottom(), top(), end(),
            vs->high_boundary());
 }
 #ifdef ASSERT
 void VirtualSpaceNode::mangle() {
   size_t word_size = capacity_words_in_vs();
   Copy::fill_to_words((HeapWord*) low(), word_size, 0xf1f1f1f1);
 }
 #endif // ASSERT
 // VirtualSpaceList methods
 // Space allocated from the VirtualSpace
 VirtualSpaceList::~VirtualSpaceList() {
   VirtualSpaceListIterator iter(virtual_space_list());
   while (iter.repeat()) {
     VirtualSpaceNode* vsl = iter.get_next();
     delete vsl;
   }
 }
 void VirtualSpaceList::inc_virtual_space_total(size_t v) {
   assert_lock_strong(SpaceManager::expand_lock());
   _virtual_space_total = _virtual_space_total + v;
 }
 void VirtualSpaceList::dec_virtual_space_total(size_t v) {
   assert_lock_strong(SpaceManager::expand_lock());
   _virtual_space_total = _virtual_space_total - v;
 }
 void VirtualSpaceList::inc_virtual_space_count() {
   assert_lock_strong(SpaceManager::expand_lock());
   _virtual_space_count++;
 }
 void VirtualSpaceList::dec_virtual_space_count() {
   assert_lock_strong(SpaceManager::expand_lock());
   _virtual_space_count--;
 }
 void ChunkManager::remove_chunk(Metachunk* chunk) {
   size_t word_size = chunk->word_size();
   ChunkIndex index = list_index(word_size);
   if (index != HumongousIndex) {
     free_chunks(index)->remove_chunk(chunk);
   } else {
     humongous_dictionary()->remove_chunk(chunk);
   }
   // Chunk is being removed from the chunks free list.
   dec_free_chunks_total(chunk->capacity_word_size());
 }
 // Walk the list of VirtualSpaceNodes and delete
 // nodes with a 0 container_count.  Remove Metachunks in
 // the node from their respective freelists.
 void VirtualSpaceList::purge() {
   assert_lock_strong(SpaceManager::expand_lock());
   // Don't use a VirtualSpaceListIterator because this
   // list is being changed and a straightforward use of an iterator is not safe.
   VirtualSpaceNode* purged_vsl = NULL;
   VirtualSpaceNode* prev_vsl = virtual_space_list();
   VirtualSpaceNode* next_vsl = prev_vsl;
   while (next_vsl != NULL) {
     VirtualSpaceNode* vsl = next_vsl;
     next_vsl = vsl->next();
     // Don't free the current virtual space since it will likely
     // be needed soon.
     if (vsl->container_count() == 0 && vsl != current_virtual_space()) {
       // Unlink it from the list
       if (prev_vsl == vsl) {
         // This is the case of the current note being the first note.
         assert(vsl == virtual_space_list(), "Expected to be the first note");
         set_virtual_space_list(vsl->next());
       } else {
         prev_vsl->set_next(vsl->next());
       }
       vsl->purge(chunk_manager());
       dec_virtual_space_total(vsl->reserved()->word_size());
       dec_virtual_space_count();
       purged_vsl = vsl;
       delete vsl;
     } else {
       prev_vsl = vsl;
     }
   }
 #ifdef ASSERT
   if (purged_vsl != NULL) {
   // List should be stable enough to use an iterator here.
   VirtualSpaceListIterator iter(virtual_space_list());
     while (iter.repeat()) {
       VirtualSpaceNode* vsl = iter.get_next();
       assert(vsl != purged_vsl, "Purge of vsl failed");
     }
   }
 #endif
 }
 size_t VirtualSpaceList::used_words_sum() {
   size_t allocated_by_vs = 0;
   VirtualSpaceListIterator iter(virtual_space_list());
   while (iter.repeat()) {
     VirtualSpaceNode* vsl = iter.get_next();
     // Sum used region [bottom, top) in each virtualspace
     allocated_by_vs += vsl->used_words_in_vs();
   }
   assert(allocated_by_vs >= chunk_manager()->free_chunks_total(),
     err_msg("Total in free chunks " SIZE_FORMAT
             " greater than total from virtual_spaces " SIZE_FORMAT,
             allocated_by_vs, chunk_manager()->free_chunks_total()));
   size_t used =
     allocated_by_vs - chunk_manager()->free_chunks_total();
   return used;
 }
 // Space available in all MetadataVirtualspaces allocated
 // for metadata.  This is the upper limit on the capacity
 // of chunks allocated out of all the MetadataVirtualspaces.
 size_t VirtualSpaceList::capacity_words_sum() {
   size_t capacity = 0;
   VirtualSpaceListIterator iter(virtual_space_list());
   while (iter.repeat()) {
     VirtualSpaceNode* vsl = iter.get_next();
     capacity += vsl->capacity_words_in_vs();
   }
   return capacity;
 }
 VirtualSpaceList::VirtualSpaceList(size_t word_size ) :
                                    _is_class(false),
                                    _virtual_space_list(NULL),
                                    _current_virtual_space(NULL),
                                    _virtual_space_total(0),
                                    _virtual_space_count(0) {
   MutexLockerEx cl(SpaceManager::expand_lock(),
                    Mutex::_no_safepoint_check_flag);
   bool initialization_succeeded = grow_vs(word_size);
   _chunk_manager.free_chunks(SpecializedIndex)->set_size(SpecializedChunk);
   _chunk_manager.free_chunks(SmallIndex)->set_size(SmallChunk);
   _chunk_manager.free_chunks(MediumIndex)->set_size(MediumChunk);
   assert(initialization_succeeded,
     " VirtualSpaceList initialization should not fail");
 }
 VirtualSpaceList::VirtualSpaceList(ReservedSpace rs) :
                                    _is_class(true),
                                    _virtual_space_list(NULL),
                                    _current_virtual_space(NULL),
                                    _virtual_space_total(0),
                                    _virtual_space_count(0) {
   MutexLockerEx cl(SpaceManager::expand_lock(),
                    Mutex::_no_safepoint_check_flag);
   VirtualSpaceNode* class_entry = new VirtualSpaceNode(rs);
   bool succeeded = class_entry->initialize();
   _chunk_manager.free_chunks(SpecializedIndex)->set_size(SpecializedChunk);
   _chunk_manager.free_chunks(SmallIndex)->set_size(ClassSmallChunk);
   _chunk_manager.free_chunks(MediumIndex)->set_size(ClassMediumChunk);
   assert(succeeded, " VirtualSpaceList initialization should not fail");
   link_vs(class_entry, rs.size()/BytesPerWord);
 }
 size_t VirtualSpaceList::free_bytes() {
   return virtual_space_list()->free_words_in_vs() * BytesPerWord;
 }
 // Allocate another meta virtual space and add it to the list.
 bool VirtualSpaceList::grow_vs(size_t vs_word_size) {
   assert_lock_strong(SpaceManager::expand_lock());
   if (vs_word_size == 0) {
     return false;
   }
   // Reserve the space
   size_t vs_byte_size = vs_word_size * BytesPerWord;
   assert(vs_byte_size % os::vm_page_size() == 0, "Not aligned");
   // Allocate the meta virtual space and initialize it.
   VirtualSpaceNode* new_entry = new VirtualSpaceNode(vs_byte_size);
   if (!new_entry->initialize()) {
     delete new_entry;
     return false;
   } else {
     // ensure lock-free iteration sees fully initialized node
     OrderAccess::storestore();
     link_vs(new_entry, vs_word_size);
     return true;
   }
 }
 void VirtualSpaceList::link_vs(VirtualSpaceNode* new_entry, size_t vs_word_size) {
   if (virtual_space_list() == NULL) {
       set_virtual_space_list(new_entry);
   } else {
     current_virtual_space()->set_next(new_entry);
   }
   set_current_virtual_space(new_entry);
   inc_virtual_space_total(vs_word_size);
   inc_virtual_space_count();
 #ifdef ASSERT
   new_entry->mangle();
 #endif
   if (TraceMetavirtualspaceAllocation && Verbose) {
     VirtualSpaceNode* vsl = current_virtual_space();
     vsl->print_on(tty);
   }
 }
 Metachunk* VirtualSpaceList::get_new_chunk(size_t word_size,
                                            size_t grow_chunks_by_words,
                                            size_t medium_chunk_bunch) {
   // Get a chunk from the chunk freelist
   Metachunk* next = chunk_manager()->chunk_freelist_allocate(grow_chunks_by_words);
   if (next != NULL) {
     next->container()->inc_container_count();
   } else {
     // Allocate a chunk out of the current virtual space.
     next = current_virtual_space()->get_chunk_vs(grow_chunks_by_words);
   }
   if (next == NULL) {
     // Not enough room in current virtual space.  Try to commit
     // more space.
     size_t expand_vs_by_words = MAX2(medium_chunk_bunch,
                                      grow_chunks_by_words);
     size_t page_size_words = os::vm_page_size() / BytesPerWord;
     size_t aligned_expand_vs_by_words = align_size_up(expand_vs_by_words,
                                                         page_size_words);
     bool vs_expanded =
       current_virtual_space()->expand_by(aligned_expand_vs_by_words, false);
     if (!vs_expanded) {
       // Should the capacity of the metaspaces be expanded for
       // this allocation?  If it's the virtual space for classes and is
       // being used for CompressedHeaders, don't allocate a new virtualspace.
       if (can_grow() && MetaspaceGC::should_expand(this, word_size)) {
         // Get another virtual space.
           size_t grow_vs_words =
             MAX2((size_t)VirtualSpaceSize, aligned_expand_vs_by_words);
         if (grow_vs(grow_vs_words)) {
           // Got it.  It's on the list now.  Get a chunk from it.
           next = current_virtual_space()->get_chunk_vs_with_expand(grow_chunks_by_words);
         }
       } else {
         // Allocation will fail and induce a GC
         if (TraceMetadataChunkAllocation && Verbose) {
           gclog_or_tty->print_cr("VirtualSpaceList::get_new_chunk():"
             " Fail instead of expand the metaspace");
         }
       }
     } else {
       // The virtual space expanded, get a new chunk
       next = current_virtual_space()->get_chunk_vs(grow_chunks_by_words);
       assert(next != NULL, "Just expanded, should succeed");
     }
   }
   assert(next == NULL || (next->next() == NULL && next->prev() == NULL),
          "New chunk is still on some list");
   return next;
 }
 Metachunk* VirtualSpaceList::get_initialization_chunk(size_t chunk_word_size,
                                                       size_t chunk_bunch) {
   // Get a chunk from the chunk freelist
   Metachunk* new_chunk = get_new_chunk(chunk_word_size,
                                        chunk_word_size,
                                        chunk_bunch);
   return new_chunk;
 }
 void VirtualSpaceList::print_on(outputStream* st) const {
   if (TraceMetadataChunkAllocation && Verbose) {
     VirtualSpaceListIterator iter(virtual_space_list());
     while (iter.repeat()) {
       VirtualSpaceNode* node = iter.get_next();
       node->print_on(st);
     }
   }
 }
 bool VirtualSpaceList::contains(const void *ptr) {
   VirtualSpaceNode* list = virtual_space_list();
   VirtualSpaceListIterator iter(list);
   while (iter.repeat()) {
     VirtualSpaceNode* node = iter.get_next();
     if (node->reserved()->contains(ptr)) {
       return true;
     }
   }
   return false;
 }
 // MetaspaceGC methods
 // VM_CollectForMetadataAllocation is the vm operation used to GC.
 // Within the VM operation after the GC the attempt to allocate the metadata
 // should succeed.  If the GC did not free enough space for the metaspace
 // allocation, the HWM is increased so that another virtualspace will be
 // allocated for the metadata.  With perm gen the increase in the perm
 // gen had bounds, MinMetaspaceExpansion and MaxMetaspaceExpansion.  The
 // metaspace policy uses those as the small and large steps for the HWM.
 //
 // After the GC the compute_new_size() for MetaspaceGC is called to
 // resize the capacity of the metaspaces.  The current implementation
 // is based on the flags MinMetaspaceFreeRatio and MaxMetaspaceFreeRatio used
 // to resize the Java heap by some GC's.  New flags can be implemented
 // if really needed.  MinMetaspaceFreeRatio is used to calculate how much
 // free space is desirable in the metaspace capacity to decide how much
 // to increase the HWM.  MaxMetaspaceFreeRatio is used to decide how much
 // free space is desirable in the metaspace capacity before decreasing
 // the HWM.
 // Calculate the amount to increase the high water mark (HWM).
 // Increase by a minimum amount (MinMetaspaceExpansion) so that
 // another expansion is not requested too soon.  If that is not
 // enough to satisfy the allocation (i.e. big enough for a word_size
 // allocation), increase by MaxMetaspaceExpansion.  If that is still
 // not enough, expand by the size of the allocation (word_size) plus
 // some.
 size_t MetaspaceGC::delta_capacity_until_GC(size_t word_size) {
   size_t before_inc = MetaspaceGC::capacity_until_GC();
   size_t min_delta_words = MinMetaspaceExpansion / BytesPerWord;
   size_t max_delta_words = MaxMetaspaceExpansion / BytesPerWord;
   size_t page_size_words = os::vm_page_size() / BytesPerWord;
   size_t size_delta_words = align_size_up(word_size, page_size_words);
   size_t delta_words = MAX2(size_delta_words, min_delta_words);
   if (delta_words > min_delta_words) {
     // Don't want to hit the high water mark on the next
     // allocation so make the delta greater than just enough
     // for this allocation.
     delta_words = MAX2(delta_words, max_delta_words);
     if (delta_words > max_delta_words) {
       // This allocation is large but the next ones are probably not
       // so increase by the minimum.
       delta_words = delta_words + min_delta_words;
     }
   }
   return delta_words;
 }
 bool MetaspaceGC::should_expand(VirtualSpaceList* vsl, size_t word_size) {
   size_t committed_capacity_bytes = MetaspaceAux::allocated_capacity_bytes();
   // If the user wants a limit, impose one.
   size_t max_metaspace_size_bytes = MaxMetaspaceSize;
   size_t metaspace_size_bytes = MetaspaceSize;
   if (!FLAG_IS_DEFAULT(MaxMetaspaceSize) &&
       MetaspaceAux::reserved_in_bytes() >= MaxMetaspaceSize) {
     return false;
   }
   // Class virtual space should always be expanded.  Call GC for the other
   // metadata virtual space.
   if (vsl == Metaspace::class_space_list()) return true;
   // If this is part of an allocation after a GC, expand
   // unconditionally.
   if (MetaspaceGC::expand_after_GC()) {
     return true;
   }
   // If the capacity is below the minimum capacity, allow the
   // expansion.  Also set the high-water-mark (capacity_until_GC)
   // to that minimum capacity so that a GC will not be induced
   // until that minimum capacity is exceeded.
   if (committed_capacity_bytes < metaspace_size_bytes ||
       capacity_until_GC() == 0) {
     set_capacity_until_GC(metaspace_size_bytes);
     return true;
   } else {
     if (committed_capacity_bytes < capacity_until_GC()) {
       return true;
     } else {
       if (TraceMetadataChunkAllocation && Verbose) {
         gclog_or_tty->print_cr("  allocation request size " SIZE_FORMAT
                         "  capacity_until_GC " SIZE_FORMAT
                         "  allocated_capacity_bytes " SIZE_FORMAT,
                         word_size,
                         capacity_until_GC(),
                         MetaspaceAux::allocated_capacity_bytes());
       }
       return false;
     }
   }
 }
 void MetaspaceGC::compute_new_size() {
   assert(_shrink_factor <= 100, "invalid shrink factor");
   uint current_shrink_factor = _shrink_factor;
   _shrink_factor = 0;
   // Until a faster way of calculating the "used" quantity is implemented,
   // use "capacity".
   const size_t used_after_gc = MetaspaceAux::allocated_capacity_bytes();
   const size_t capacity_until_GC = MetaspaceGC::capacity_until_GC();
   const double minimum_free_percentage = MinMetaspaceFreeRatio / 100.0;
   const double maximum_used_percentage = 1.0 - minimum_free_percentage;
   const double min_tmp = used_after_gc / maximum_used_percentage;
   size_t minimum_desired_capacity =
     (size_t)MIN2(min_tmp, double(max_uintx));
   // Don't shrink less than the initial generation size
   minimum_desired_capacity = MAX2(minimum_desired_capacity,
                                   MetaspaceSize);
   if (PrintGCDetails && Verbose) {
     gclog_or_tty->print_cr("\nMetaspaceGC::compute_new_size: ");
     gclog_or_tty->print_cr("  "
                   "  minimum_free_percentage: %6.2f"
                   "  maximum_used_percentage: %6.2f",
                   minimum_free_percentage,
                   maximum_used_percentage);
     gclog_or_tty->print_cr("  "
                   "   used_after_gc       : %6.1fKB",
                   used_after_gc / (double) K);
   }
   size_t shrink_bytes = 0;
   if (capacity_until_GC < minimum_desired_capacity) {
     // If we have less capacity below the metaspace HWM, then
     // increment the HWM.
     size_t expand_bytes = minimum_desired_capacity - capacity_until_GC;
     // Don't expand unless it's significant
     if (expand_bytes >= MinMetaspaceExpansion) {
       MetaspaceGC::set_capacity_until_GC(capacity_until_GC + expand_bytes);
     }
     if (PrintGCDetails && Verbose) {
       size_t new_capacity_until_GC = capacity_until_GC;
       gclog_or_tty->print_cr("    expanding:"
                     "  minimum_desired_capacity: %6.1fKB"
                     "  expand_bytes: %6.1fKB"
                     "  MinMetaspaceExpansion: %6.1fKB"
                     "  new metaspace HWM:  %6.1fKB",
                     minimum_desired_capacity / (double) K,
                     expand_bytes / (double) K,
                     MinMetaspaceExpansion / (double) K,
                     new_capacity_until_GC / (double) K);
     }
     return;
   }
   // No expansion, now see if we want to shrink
   // We would never want to shrink more than this
   size_t max_shrink_bytes = capacity_until_GC - minimum_desired_capacity;
   assert(max_shrink_bytes >= 0, err_msg("max_shrink_bytes " SIZE_FORMAT,
     max_shrink_bytes));
   // Should shrinking be considered?
   if (MaxMetaspaceFreeRatio < 100) {
     const double maximum_free_percentage = MaxMetaspaceFreeRatio / 100.0;
     const double minimum_used_percentage = 1.0 - maximum_free_percentage;
     const double max_tmp = used_after_gc / minimum_used_percentage;
     size_t maximum_desired_capacity = (size_t)MIN2(max_tmp, double(max_uintx));
     maximum_desired_capacity = MAX2(maximum_desired_capacity,
                                     MetaspaceSize);
     if (PrintGCDetails && Verbose) {
       gclog_or_tty->print_cr("  "
                              "  maximum_free_percentage: %6.2f"
                              "  minimum_used_percentage: %6.2f",
                              maximum_free_percentage,
                              minimum_used_percentage);
       gclog_or_tty->print_cr("  "
                              "  minimum_desired_capacity: %6.1fKB"
                              "  maximum_desired_capacity: %6.1fKB",
                              minimum_desired_capacity / (double) K,
                              maximum_desired_capacity / (double) K);
     }
     assert(minimum_desired_capacity <= maximum_desired_capacity,
            "sanity check");
     if (capacity_until_GC > maximum_desired_capacity) {
       // Capacity too large, compute shrinking size
       shrink_bytes = capacity_until_GC - maximum_desired_capacity;
       // We don't want shrink all the way back to initSize if people call
       // System.gc(), because some programs do that between "phases" and then
       // we'd just have to grow the heap up again for the next phase.  So we
       // damp the shrinking: 0% on the first call, 10% on the second call, 40%
       // on the third call, and 100% by the fourth call.  But if we recompute
       // size without shrinking, it goes back to 0%.
       shrink_bytes = shrink_bytes / 100 * current_shrink_factor;
       assert(shrink_bytes <= max_shrink_bytes,
         err_msg("invalid shrink size " SIZE_FORMAT " not <= " SIZE_FORMAT,
           shrink_bytes, max_shrink_bytes));
       if (current_shrink_factor == 0) {
         _shrink_factor = 10;
       } else {
         _shrink_factor = MIN2(current_shrink_factor * 4, (uint) 100);
       }
       if (PrintGCDetails && Verbose) {
         gclog_or_tty->print_cr("  "
                       "  shrinking:"
                       "  initSize: %.1fK"
                       "  maximum_desired_capacity: %.1fK",
                       MetaspaceSize / (double) K,
                       maximum_desired_capacity / (double) K);
         gclog_or_tty->print_cr("  "
                       "  shrink_bytes: %.1fK"
                       "  current_shrink_factor: %d"
                       "  new shrink factor: %d"
                       "  MinMetaspaceExpansion: %.1fK",
                       shrink_bytes / (double) K,
                       current_shrink_factor,
                       _shrink_factor,
                       MinMetaspaceExpansion / (double) K);
       }
     }
   }
   // Don't shrink unless it's significant
   if (shrink_bytes >= MinMetaspaceExpansion &&
       ((capacity_until_GC - shrink_bytes) >= MetaspaceSize)) {
     MetaspaceGC::set_capacity_until_GC(capacity_until_GC - shrink_bytes);
   }
 }
 // Metadebug methods
 void Metadebug::deallocate_chunk_a_lot(SpaceManager* sm,
                                        size_t chunk_word_size){
 #ifdef ASSERT
   VirtualSpaceList* vsl = sm->vs_list();
   if (MetaDataDeallocateALot &&
       Metadebug::deallocate_chunk_a_lot_count() % MetaDataDeallocateALotInterval == 0 ) {
     Metadebug::reset_deallocate_chunk_a_lot_count();
     for (uint i = 0; i < metadata_deallocate_a_lock_chunk; i++) {
       Metachunk* dummy_chunk = vsl->current_virtual_space()->take_from_committed(chunk_word_size);
       if (dummy_chunk == NULL) {
         break;
       }
       vsl->chunk_manager()->chunk_freelist_deallocate(dummy_chunk);
       if (TraceMetadataChunkAllocation && Verbose) {
         gclog_or_tty->print("Metadebug::deallocate_chunk_a_lot: %d) ",
                                sm->sum_count_in_chunks_in_use());
         dummy_chunk->print_on(gclog_or_tty);
         gclog_or_tty->print_cr("  Free chunks total %d  count %d",
                                vsl->chunk_manager()->free_chunks_total(),
                                vsl->chunk_manager()->free_chunks_count());
       }
     }
   } else {
     Metadebug::inc_deallocate_chunk_a_lot_count();
   }
 #endif
 }
 void Metadebug::deallocate_block_a_lot(SpaceManager* sm,
                                        size_t raw_word_size){
 #ifdef ASSERT
   if (MetaDataDeallocateALot &&
         Metadebug::deallocate_block_a_lot_count() % MetaDataDeallocateALotInterval == 0 ) {
     Metadebug::set_deallocate_block_a_lot_count(0);
     for (uint i = 0; i < metadata_deallocate_a_lot_block; i++) {
       MetaWord* dummy_block = sm->allocate_work(raw_word_size);
       if (dummy_block == 0) {
         break;
       }
       sm->deallocate(dummy_block, raw_word_size);
     }
   } else {
     Metadebug::inc_deallocate_block_a_lot_count();
   }
 #endif
 }
 void Metadebug::init_allocation_fail_alot_count() {
   if (MetadataAllocationFailALot) {
     _allocation_fail_alot_count =
 +(long)((double)MetadataAllocationFailALotInterval*os::random()/(max_jint+1.0));
   }
 }
 #ifdef ASSERT
 bool Metadebug::test_metadata_failure() {
   if (MetadataAllocationFailALot &&
       Threads::is_vm_complete()) {
     if (_allocation_fail_alot_count > 0) {
       _allocation_fail_alot_count--;
     } else {
       if (TraceMetadataChunkAllocation && Verbose) {
         gclog_or_tty->print_cr("Metadata allocation failing for "
                                "MetadataAllocationFailALot");
       }
       init_allocation_fail_alot_count();
       return true;
     }
   }
   return false;
 }
 #endif
 // ChunkManager methods
 // Verification of _free_chunks_total and _free_chunks_count does not
 // work with the CMS collector because its use of additional locks
 // complicate the mutex deadlock detection but it can still be useful
 // for detecting errors in the chunk accounting with other collectors.
 size_t ChunkManager::free_chunks_total() {
 #ifdef ASSERT
   if (!UseConcMarkSweepGC && !SpaceManager::expand_lock()->is_locked()) {
     MutexLockerEx cl(SpaceManager::expand_lock(),
                      Mutex::_no_safepoint_check_flag);
     slow_locked_verify_free_chunks_total();
   }
 #endif
   return _free_chunks_total;
 }
 size_t ChunkManager::free_chunks_total_in_bytes() {
   return free_chunks_total() * BytesPerWord;
 }
 size_t ChunkManager::free_chunks_count() {
 #ifdef ASSERT
   if (!UseConcMarkSweepGC && !SpaceManager::expand_lock()->is_locked()) {
     MutexLockerEx cl(SpaceManager::expand_lock(),
                      Mutex::_no_safepoint_check_flag);
     // This lock is only needed in debug because the verification
     // of the _free_chunks_totals walks the list of free chunks
     slow_locked_verify_free_chunks_count();
   }
 #endif
   return _free_chunks_count;
 }
 void ChunkManager::locked_verify_free_chunks_total() {
   assert_lock_strong(SpaceManager::expand_lock());
   assert(sum_free_chunks() == _free_chunks_total,
     err_msg("_free_chunks_total " SIZE_FORMAT " is not the"
            " same as sum " SIZE_FORMAT, _free_chunks_total,
            sum_free_chunks()));
 }
 void ChunkManager::verify_free_chunks_total() {
   MutexLockerEx cl(SpaceManager::expand_lock(),
                      Mutex::_no_safepoint_check_flag);
   locked_verify_free_chunks_total();
 }
 void ChunkManager::locked_verify_free_chunks_count() {
   assert_lock_strong(SpaceManager::expand_lock());
   assert(sum_free_chunks_count() == _free_chunks_count,
     err_msg("_free_chunks_count " SIZE_FORMAT " is not the"
            " same as sum " SIZE_FORMAT, _free_chunks_count,
            sum_free_chunks_count()));
 }
 void ChunkManager::verify_free_chunks_count() {
 #ifdef ASSERT
   MutexLockerEx cl(SpaceManager::expand_lock(),
                      Mutex::_no_safepoint_check_flag);
   locked_verify_free_chunks_count();
 #endif
 }
 void ChunkManager::verify() {
   MutexLockerEx cl(SpaceManager::expand_lock(),
                      Mutex::_no_safepoint_check_flag);
   locked_verify();
 }
 void ChunkManager::locked_verify() {
   locked_verify_free_chunks_count();
   locked_verify_free_chunks_total();
 }
 void ChunkManager::locked_print_free_chunks(outputStream* st) {
   assert_lock_strong(SpaceManager::expand_lock());
   st->print_cr("Free chunk total " SIZE_FORMAT "  count " SIZE_FORMAT,
                 _free_chunks_total, _free_chunks_count);
 }
 void ChunkManager::locked_print_sum_free_chunks(outputStream* st) {
   assert_lock_strong(SpaceManager::expand_lock());
   st->print_cr("Sum free chunk total " SIZE_FORMAT "  count " SIZE_FORMAT,
                 sum_free_chunks(), sum_free_chunks_count());
 }
 ChunkList* ChunkManager::free_chunks(ChunkIndex index) {
   return &_free_chunks[index];
 }
 // These methods that sum the free chunk lists are used in printing
 // methods that are used in product builds.
 size_t ChunkManager::sum_free_chunks() {
   assert_lock_strong(SpaceManager::expand_lock());
   size_t result = 0;
   for (ChunkIndex i = ZeroIndex; i < NumberOfFreeLists; i = next_chunk_index(i)) {
     ChunkList* list = free_chunks(i);
     if (list == NULL) {
       continue;
     }
     result = result + list->count() * list->size();
   }
   result = result + humongous_dictionary()->total_size();
   return result;
 }
 size_t ChunkManager::sum_free_chunks_count() {
   assert_lock_strong(SpaceManager::expand_lock());
   size_t count = 0;
   for (ChunkIndex i = ZeroIndex; i < NumberOfFreeLists; i = next_chunk_index(i)) {
     ChunkList* list = free_chunks(i);
     if (list == NULL) {
       continue;
     }
     count = count + list->count();
   }
   count = count + humongous_dictionary()->total_free_blocks();
   return count;
 }
 ChunkList* ChunkManager::find_free_chunks_list(size_t word_size) {
   ChunkIndex index = list_index(word_size);
   assert(index < HumongousIndex, "No humongous list");
   return free_chunks(index);
 }
 void ChunkManager::free_chunks_put(Metachunk* chunk) {
   assert_lock_strong(SpaceManager::expand_lock());
   ChunkList* free_list = find_free_chunks_list(chunk->word_size());
   chunk->set_next(free_list->head());
   free_list->set_head(chunk);
   // chunk is being returned to the chunk free list
   inc_free_chunks_total(chunk->capacity_word_size());
   slow_locked_verify();
 }
 void ChunkManager::chunk_freelist_deallocate(Metachunk* chunk) {
   // The deallocation of a chunk originates in the freelist
   // manangement code for a Metaspace and does not hold the
   // lock.
   assert(chunk != NULL, "Deallocating NULL");
   assert_lock_strong(SpaceManager::expand_lock());
   slow_locked_verify();
   if (TraceMetadataChunkAllocation) {
     tty->print_cr("ChunkManager::chunk_freelist_deallocate: chunk "
                   PTR_FORMAT "  size " SIZE_FORMAT,
                   chunk, chunk->word_size());
   }
   free_chunks_put(chunk);
 }
 Metachunk* ChunkManager::free_chunks_get(size_t word_size) {
   assert_lock_strong(SpaceManager::expand_lock());
   slow_locked_verify();
   Metachunk* chunk = NULL;
   if (list_index(word_size) != HumongousIndex) {
     ChunkList* free_list = find_free_chunks_list(word_size);
     assert(free_list != NULL, "Sanity check");
     chunk = free_list->head();
     debug_only(Metachunk* debug_head = chunk;)
     if (chunk == NULL) {
       return NULL;
     }
     // Remove the chunk as the head of the list.
     free_list->remove_chunk(chunk);
     // Chunk is being removed from the chunks free list.
     dec_free_chunks_total(chunk->capacity_word_size());
     if (TraceMetadataChunkAllocation && Verbose) {
       tty->print_cr("ChunkManager::free_chunks_get: free_list "
                     PTR_FORMAT " head " PTR_FORMAT " size " SIZE_FORMAT,
                     free_list, chunk, chunk->word_size());
     }
   } else {
     chunk = humongous_dictionary()->get_chunk(
       word_size,
       FreeBlockDictionary<Metachunk>::atLeast);
     if (chunk != NULL) {
       if (TraceMetadataHumongousAllocation) {
         size_t waste = chunk->word_size() - word_size;
         tty->print_cr("Free list allocate humongous chunk size " SIZE_FORMAT
                       " for requested size " SIZE_FORMAT
                       " waste " SIZE_FORMAT,
                       chunk->word_size(), word_size, waste);
       }
       // Chunk is being removed from the chunks free list.
       dec_free_chunks_total(chunk->capacity_word_size());
     } else {
       return NULL;
     }
   }
   // Remove it from the links to this freelist
   chunk->set_next(NULL);
   chunk->set_prev(NULL);
 #ifdef ASSERT
   // Chunk is no longer on any freelist. Setting to false make container_count_slow()
   // work.
   chunk->set_is_free(false);
 #endif
   slow_locked_verify();
   return chunk;
 }
 Metachunk* ChunkManager::chunk_freelist_allocate(size_t word_size) {
   assert_lock_strong(SpaceManager::expand_lock());
   slow_locked_verify();
   // Take from the beginning of the list
   Metachunk* chunk = free_chunks_get(word_size);
   if (chunk == NULL) {
     return NULL;
   }
   assert((word_size <= chunk->word_size()) ||
          list_index(chunk->word_size() == HumongousIndex),
          "Non-humongous variable sized chunk");
   if (TraceMetadataChunkAllocation) {
     size_t list_count;
     if (list_index(word_size) < HumongousIndex) {
       ChunkList* list = find_free_chunks_list(word_size);
       list_count = list->count();
     } else {
       list_count = humongous_dictionary()->total_count();
     }
     tty->print("ChunkManager::chunk_freelist_allocate: " PTR_FORMAT " chunk "
                PTR_FORMAT "  size " SIZE_FORMAT " count " SIZE_FORMAT " ",
                this, chunk, chunk->word_size(), list_count);
     locked_print_free_chunks(tty);
   }
   return chunk;
 }
 void ChunkManager::print_on(outputStream* out) {
   if (PrintFLSStatistics != 0) {
     humongous_dictionary()->report_statistics();
   }
 }
 // SpaceManager methods
 void SpaceManager::get_initial_chunk_sizes(Metaspace::MetaspaceType type,
                                            size_t* chunk_word_size,
                                            size_t* class_chunk_word_size) {
   switch (type) {
   case Metaspace::BootMetaspaceType:
     *chunk_word_size = Metaspace::first_chunk_word_size();
     *class_chunk_word_size = Metaspace::first_class_chunk_word_size();
     break;
   case Metaspace::ROMetaspaceType:
     *chunk_word_size = SharedReadOnlySize / wordSize;
     *class_chunk_word_size = ClassSpecializedChunk;
     break;
   case Metaspace::ReadWriteMetaspaceType:
     *chunk_word_size = SharedReadWriteSize / wordSize;
     *class_chunk_word_size = ClassSpecializedChunk;
     break;
   case Metaspace::AnonymousMetaspaceType:
   case Metaspace::ReflectionMetaspaceType:
     *chunk_word_size = SpecializedChunk;
     *class_chunk_word_size = ClassSpecializedChunk;
     break;
   default:
     *chunk_word_size = SmallChunk;
     *class_chunk_word_size = ClassSmallChunk;
     break;
   }
   assert(*chunk_word_size != 0 && *class_chunk_word_size != 0,
     err_msg("Initial chunks sizes bad: data  " SIZE_FORMAT
             " class " SIZE_FORMAT,
             *chunk_word_size, *class_chunk_word_size));
 }
 size_t SpaceManager::sum_free_in_chunks_in_use() const {
   MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag);
   size_t free = 0;
   for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) {
     Metachunk* chunk = chunks_in_use(i);
     while (chunk != NULL) {
       free += chunk->free_word_size();
       chunk = chunk->next();
     }
   }
   return free;
 }
 size_t SpaceManager::sum_waste_in_chunks_in_use() const {
   MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag);
   size_t result = 0;
   for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) {
    result += sum_waste_in_chunks_in_use(i);
   }
   return result;
 }
 size_t SpaceManager::sum_waste_in_chunks_in_use(ChunkIndex index) const {
   size_t result = 0;
   Metachunk* chunk = chunks_in_use(index);
   // Count the free space in all the chunk but not the
   // current chunk from which allocations are still being done.
   if (chunk != NULL) {
     Metachunk* prev = chunk;
     while (chunk != NULL && chunk != current_chunk()) {
       result += chunk->free_word_size();
       prev = chunk;
       chunk = chunk->next();
     }
   }
   return result;
 }
 size_t SpaceManager::sum_capacity_in_chunks_in_use() const {
   // For CMS use "allocated_chunks_words()" which does not need the
   // Metaspace lock.  For the other collectors sum over the
   // lists.  Use both methods as a check that "allocated_chunks_words()"
   // is correct.  That is, sum_capacity_in_chunks() is too expensive
   // to use in the product and allocated_chunks_words() should be used
   // but allow for  checking that allocated_chunks_words() returns the same
   // value as sum_capacity_in_chunks_in_use() which is the definitive
   // answer.
   if (UseConcMarkSweepGC) {
     return allocated_chunks_words();
   } else {
     MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag);
     size_t sum = 0;
     for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) {
       Metachunk* chunk = chunks_in_use(i);
       while (chunk != NULL) {
         sum += chunk->capacity_word_size();
         chunk = chunk->next();
       }
     }
   return sum;
   }
 }
 size_t SpaceManager::sum_count_in_chunks_in_use() {
   size_t count = 0;
   for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) {
     count = count + sum_count_in_chunks_in_use(i);
   }
   return count;
 }
 size_t SpaceManager::sum_count_in_chunks_in_use(ChunkIndex i) {
   size_t count = 0;
   Metachunk* chunk = chunks_in_use(i);
   while (chunk != NULL) {
     count++;
     chunk = chunk->next();
   }
   return count;
 }
 size_t SpaceManager::sum_used_in_chunks_in_use() const {
   MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag);
   size_t used = 0;
   for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) {
     Metachunk* chunk = chunks_in_use(i);
     while (chunk != NULL) {
       used += chunk->used_word_size();
       chunk = chunk->next();
     }
   }
   return used;
 }
 void SpaceManager::locked_print_chunks_in_use_on(outputStream* st) const {
   for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) {
     Metachunk* chunk = chunks_in_use(i);
     st->print("SpaceManager: %s " PTR_FORMAT,
                  chunk_size_name(i), chunk);
     if (chunk != NULL) {
       st->print_cr(" free " SIZE_FORMAT,
                    chunk->free_word_size());
     } else {
       st->print_cr("");
     }
   }
   vs_list()->chunk_manager()->locked_print_free_chunks(st);
   vs_list()->chunk_manager()->locked_print_sum_free_chunks(st);
 }
 size_t SpaceManager::calc_chunk_size(size_t word_size) {
   // Decide between a small chunk and a medium chunk.  Up to
   // _small_chunk_limit small chunks can be allocated but
   // once a medium chunk has been allocated, no more small
   // chunks will be allocated.
   size_t chunk_word_size;
   if (chunks_in_use(MediumIndex) == NULL &&
       (!has_small_chunk_limit() ||
        sum_count_in_chunks_in_use(SmallIndex) < _small_chunk_limit)) {
     chunk_word_size = (size_t) small_chunk_size();
     if (word_size + Metachunk::overhead() > small_chunk_size()) {
       chunk_word_size = medium_chunk_size();
     }
   } else {
     chunk_word_size = medium_chunk_size();
   }
   // Might still need a humongous chunk.  Enforce an
   // eight word granularity to facilitate reuse (some
   // wastage but better chance of reuse).
   size_t if_humongous_sized_chunk =
     align_size_up(word_size + Metachunk::overhead(),
                   HumongousChunkGranularity);
   chunk_word_size =
     MAX2((size_t) chunk_word_size, if_humongous_sized_chunk);
   assert(!SpaceManager::is_humongous(word_size) ||
          chunk_word_size == if_humongous_sized_chunk,
          err_msg("Size calculation is wrong, word_size " SIZE_FORMAT
                  " chunk_word_size " SIZE_FORMAT,
                  word_size, chunk_word_size));
   if (TraceMetadataHumongousAllocation &&
       SpaceManager::is_humongous(word_size)) {
     gclog_or_tty->print_cr("Metadata humongous allocation:");
     gclog_or_tty->print_cr("  word_size " PTR_FORMAT, word_size);
     gclog_or_tty->print_cr("  chunk_word_size " PTR_FORMAT,
                            chunk_word_size);
     gclog_or_tty->print_cr("    chunk overhead " PTR_FORMAT,
                            Metachunk::overhead());
   }
   return chunk_word_size;
 }
 MetaWord* SpaceManager::grow_and_allocate(size_t word_size) {
   assert(vs_list()->current_virtual_space() != NULL,
          "Should have been set");
   assert(current_chunk() == NULL ||
          current_chunk()->allocate(word_size) == NULL,
          "Don't need to expand");
   MutexLockerEx cl(SpaceManager::expand_lock(), Mutex::_no_safepoint_check_flag);
   if (TraceMetadataChunkAllocation && Verbose) {
     size_t words_left = 0;
     size_t words_used = 0;
     if (current_chunk() != NULL) {
       words_left = current_chunk()->free_word_size();
       words_used = current_chunk()->used_word_size();
     }
     gclog_or_tty->print_cr("SpaceManager::grow_and_allocate for " SIZE_FORMAT
                            " words " SIZE_FORMAT " words used " SIZE_FORMAT
                            " words left",
                             word_size, words_used, words_left);
   }
   // Get another chunk out of the virtual space
   size_t grow_chunks_by_words = calc_chunk_size(word_size);
   Metachunk* next = get_new_chunk(word_size, grow_chunks_by_words);
   // If a chunk was available, add it to the in-use chunk list
   // and do an allocation from it.
   if (next != NULL) {
     Metadebug::deallocate_chunk_a_lot(this, grow_chunks_by_words);
     // Add to this manager's list of chunks in use.
     add_chunk(next, false);
     return next->allocate(word_size);
   }
   return NULL;
 }
 void SpaceManager::print_on(outputStream* st) const {
   for (ChunkIndex i = ZeroIndex;
        i < NumberOfInUseLists ;
        i = next_chunk_index(i) ) {
     st->print_cr("  chunks_in_use " PTR_FORMAT " chunk size " PTR_FORMAT,
                  chunks_in_use(i),
                  chunks_in_use(i) == NULL ? 0 : chunks_in_use(i)->word_size());
   }
   st->print_cr("    waste:  Small " SIZE_FORMAT " Medium " SIZE_FORMAT
                " Humongous " SIZE_FORMAT,
                sum_waste_in_chunks_in_use(SmallIndex),
                sum_waste_in_chunks_in_use(MediumIndex),
                sum_waste_in_chunks_in_use(HumongousIndex));
   // block free lists
   if (block_freelists() != NULL) {
     st->print_cr("total in block free lists " SIZE_FORMAT,
       block_freelists()->total_size());
   }
 }
 SpaceManager::SpaceManager(Mutex* lock,
                            VirtualSpaceList* vs_list) :
   _vs_list(vs_list),
   _allocated_blocks_words(0),
   _allocated_chunks_words(0),
   _allocated_chunks_count(0),
   _lock(lock)
 {
   initialize();
 }
 void SpaceManager::inc_size_metrics(size_t words) {
   assert_lock_strong(SpaceManager::expand_lock());
   // Total of allocated Metachunks and allocated Metachunks count
   // for each SpaceManager
   _allocated_chunks_words = _allocated_chunks_words + words;
   _allocated_chunks_count++;
   // Global total of capacity in allocated Metachunks
   MetaspaceAux::inc_capacity(words);
   // Global total of allocated Metablocks.
   // used_words_slow() includes the overhead in each
   // Metachunk so include it in the used when the
   // Metachunk is first added (so only added once per
   // Metachunk).
   MetaspaceAux::inc_used(Metachunk::overhead());
 }
 void SpaceManager::inc_used_metrics(size_t words) {
   // Add to the per SpaceManager total
   Atomic::add_ptr(words, &_allocated_blocks_words);
   // Add to the global total
   MetaspaceAux::inc_used(words);
 }
 void SpaceManager::dec_total_from_size_metrics() {
   MetaspaceAux::dec_capacity(allocated_chunks_words());
   MetaspaceAux::dec_used(allocated_blocks_words());
   // Also deduct the overhead per Metachunk
   MetaspaceAux::dec_used(allocated_chunks_count() * Metachunk::overhead());
 }
 void SpaceManager::initialize() {
   Metadebug::init_allocation_fail_alot_count();
   for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) {
     _chunks_in_use[i] = NULL;
   }
   _current_chunk = NULL;
   if (TraceMetadataChunkAllocation && Verbose) {
     gclog_or_tty->print_cr("SpaceManager(): " PTR_FORMAT, this);
   }
 }
 void ChunkManager::return_chunks(ChunkIndex index, Metachunk* chunks) {
   if (chunks == NULL) {
     return;
   }
   ChunkList* list = free_chunks(index);
   assert(list->size() == chunks->word_size(), "Mismatch in chunk sizes");
   assert_lock_strong(SpaceManager::expand_lock());
   Metachunk* cur = chunks;
   // This returns chunks one at a time.  If a new
   // class List can be created that is a base class
   // of FreeList then something like FreeList::prepend()
   // can be used in place of this loop
   while (cur != NULL) {
     assert(cur->container() != NULL, "Container should have been set");
     cur->container()->dec_container_count();
     // Capture the next link before it is changed
     // by the call to return_chunk_at_head();
     Metachunk* next = cur->next();
     cur->set_is_free(true);
     list->return_chunk_at_head(cur);
     cur = next;
   }
 }
 SpaceManager::~SpaceManager() {
   // This call this->_lock which can't be done while holding expand_lock()
   assert(sum_capacity_in_chunks_in_use() == allocated_chunks_words(),
     err_msg("sum_capacity_in_chunks_in_use() " SIZE_FORMAT
             " allocated_chunks_words() " SIZE_FORMAT,
             sum_capacity_in_chunks_in_use(), allocated_chunks_words()));
   MutexLockerEx fcl(SpaceManager::expand_lock(),
                     Mutex::_no_safepoint_check_flag);
   ChunkManager* chunk_manager = vs_list()->chunk_manager();
   chunk_manager->slow_locked_verify();
   dec_total_from_size_metrics();
   if (TraceMetadataChunkAllocation && Verbose) {
     gclog_or_tty->print_cr("~SpaceManager(): " PTR_FORMAT, this);
     locked_print_chunks_in_use_on(gclog_or_tty);
   }
   // Do not mangle freed Metachunks.  The chunk size inside Metachunks
   // is during the freeing of a VirtualSpaceNodes.
   // Have to update before the chunks_in_use lists are emptied
   // below.
   chunk_manager->inc_free_chunks_total(allocated_chunks_words(),
                                        sum_count_in_chunks_in_use());
   // Add all the chunks in use by this space manager
   // to the global list of free chunks.
   // Follow each list of chunks-in-use and add them to the
   // free lists.  Each list is NULL terminated.
   for (ChunkIndex i = ZeroIndex; i < HumongousIndex; i = next_chunk_index(i)) {
     if (TraceMetadataChunkAllocation && Verbose) {
       gclog_or_tty->print_cr("returned %d %s chunks to freelist",
                              sum_count_in_chunks_in_use(i),
                              chunk_size_name(i));
     }
     Metachunk* chunks = chunks_in_use(i);
     chunk_manager->return_chunks(i, chunks);
     set_chunks_in_use(i, NULL);
     if (TraceMetadataChunkAllocation && Verbose) {
       gclog_or_tty->print_cr("updated freelist count %d %s",
                              chunk_manager->free_chunks(i)->count(),
                              chunk_size_name(i));
     }
     assert(i != HumongousIndex, "Humongous chunks are handled explicitly later");
   }
   // The medium chunk case may be optimized by passing the head and
   // tail of the medium chunk list to add_at_head().  The tail is often
   // the current chunk but there are probably exceptions.
   // Humongous chunks
   if (TraceMetadataChunkAllocation && Verbose) {
     gclog_or_tty->print_cr("returned %d %s humongous chunks to dictionary",
                             sum_count_in_chunks_in_use(HumongousIndex),
                             chunk_size_name(HumongousIndex));
     gclog_or_tty->print("Humongous chunk dictionary: ");
   }
   // Humongous chunks are never the current chunk.
   Metachunk* humongous_chunks = chunks_in_use(HumongousIndex);
   while (humongous_chunks != NULL) {
 #ifdef ASSERT
     humongous_chunks->set_is_free(true);
 #endif
     if (TraceMetadataChunkAllocation && Verbose) {
       gclog_or_tty->print(PTR_FORMAT " (" SIZE_FORMAT ") ",
                           humongous_chunks,
                           humongous_chunks->word_size());
     }
     assert(humongous_chunks->word_size() == (size_t)
            align_size_up(humongous_chunks->word_size(),
                              HumongousChunkGranularity),
            err_msg("Humongous chunk size is wrong: word size " SIZE_FORMAT
                    " granularity %d",
                    humongous_chunks->word_size(), HumongousChunkGranularity));
     Metachunk* next_humongous_chunks = humongous_chunks->next();
     humongous_chunks->container()->dec_container_count();
     chunk_manager->humongous_dictionary()->return_chunk(humongous_chunks);
     humongous_chunks = next_humongous_chunks;
   }
   if (TraceMetadataChunkAllocation && Verbose) {
     gclog_or_tty->print_cr("");
     gclog_or_tty->print_cr("updated dictionary count %d %s",
                      chunk_manager->humongous_dictionary()->total_count(),
                      chunk_size_name(HumongousIndex));
   }
   chunk_manager->slow_locked_verify();
 }
 const char* SpaceManager::chunk_size_name(ChunkIndex index) const {
   switch (index) {
     case SpecializedIndex:
       return "Specialized";
     case SmallIndex:
       return "Small";
     case MediumIndex:
       return "Medium";
     case HumongousIndex:
       return "Humongous";
     default:
       return NULL;
   }
 }
 ChunkIndex ChunkManager::list_index(size_t size) {
   switch (size) {
     case SpecializedChunk:
       assert(SpecializedChunk == ClassSpecializedChunk,
              "Need branch for ClassSpecializedChunk");
       return SpecializedIndex;
     case SmallChunk:
     case ClassSmallChunk:
       return SmallIndex;
     case MediumChunk:
     case ClassMediumChunk:
       return MediumIndex;
     default:
       assert(size > MediumChunk || size > ClassMediumChunk,
              "Not a humongous chunk");
       return HumongousIndex;
   }
 }
 void SpaceManager::deallocate(MetaWord* p, size_t word_size) {
   assert_lock_strong(_lock);
   size_t min_size = TreeChunk<Metablock, FreeList>::min_size();
   assert(word_size >= min_size,
     err_msg("Should not deallocate dark matter " SIZE_FORMAT, word_size));
   block_freelists()->return_block(p, word_size);
 }
 // Adds a chunk to the list of chunks in use.
 void SpaceManager::add_chunk(Metachunk* new_chunk, bool make_current) {
   assert(new_chunk != NULL, "Should not be NULL");
   assert(new_chunk->next() == NULL, "Should not be on a list");
   new_chunk->reset_empty();
   // Find the correct list and and set the current
   // chunk for that list.
   ChunkIndex index = ChunkManager::list_index(new_chunk->word_size());
   if (index != HumongousIndex) {
     set_current_chunk(new_chunk);
     new_chunk->set_next(chunks_in_use(index));
     set_chunks_in_use(index, new_chunk);
   } else {
     // For null class loader data and DumpSharedSpaces, the first chunk isn't
     // small, so small will be null.  Link this first chunk as the current
     // chunk.
     if (make_current) {
       // Set as the current chunk but otherwise treat as a humongous chunk.
       set_current_chunk(new_chunk);
     }
     // Link at head.  The _current_chunk only points to a humongous chunk for
     // the null class loader metaspace (class and data virtual space managers)
     // any humongous chunks so will not point to the tail
     // of the humongous chunks list.
     new_chunk->set_next(chunks_in_use(HumongousIndex));
     set_chunks_in_use(HumongousIndex, new_chunk);
     assert(new_chunk->word_size() > medium_chunk_size(), "List inconsistency");
   }
   // Add to the running sum of capacity
   inc_size_metrics(new_chunk->word_size());
   assert(new_chunk->is_empty(), "Not ready for reuse");
   if (TraceMetadataChunkAllocation && Verbose) {
     gclog_or_tty->print("SpaceManager::add_chunk: %d) ",
                         sum_count_in_chunks_in_use());
     new_chunk->print_on(gclog_or_tty);
     if (vs_list() != NULL) {
       vs_list()->chunk_manager()->locked_print_free_chunks(tty);
     }
   }
 }
 Metachunk* SpaceManager::get_new_chunk(size_t word_size,
                                        size_t grow_chunks_by_words) {
   Metachunk* next = vs_list()->get_new_chunk(word_size,
                                              grow_chunks_by_words,
                                              medium_chunk_bunch());
   if (TraceMetadataHumongousAllocation &&
       SpaceManager::is_humongous(next->word_size())) {
     gclog_or_tty->print_cr("  new humongous chunk word size " PTR_FORMAT,
                            next->word_size());
   }
   return next;
 }
 MetaWord* SpaceManager::allocate(size_t word_size) {
   MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag);
   // If only the dictionary is going to be used (i.e., no
   // indexed free list), then there is a minimum size requirement.
   // MinChunkSize is a placeholder for the real minimum size JJJ
   size_t byte_size = word_size * BytesPerWord;
   size_t byte_size_with_overhead = byte_size + Metablock::overhead();
   size_t raw_bytes_size = MAX2(byte_size_with_overhead,
                                Metablock::min_block_byte_size());
   raw_bytes_size = ARENA_ALIGN(raw_bytes_size);
   size_t raw_word_size = raw_bytes_size / BytesPerWord;
   assert(raw_word_size * BytesPerWord == raw_bytes_size, "Size problem");
   BlockFreelist* fl =  block_freelists();
   MetaWord* p = NULL;
   // Allocation from the dictionary is expensive in the sense that
   // the dictionary has to be searched for a size.  Don't allocate
   // from the dictionary until it starts to get fat.  Is this
   // a reasonable policy?  Maybe an skinny dictionary is fast enough
   // for allocations.  Do some profiling.  JJJ
   if (fl->total_size() > allocation_from_dictionary_limit) {
     p = fl->get_block(raw_word_size);
   }
   if (p == NULL) {
     p = allocate_work(raw_word_size);
   }
   Metadebug::deallocate_block_a_lot(this, raw_word_size);
   return p;
 }
 // Returns the address of spaced allocated for "word_size".
 // This methods does not know about blocks (Metablocks)
 MetaWord* SpaceManager::allocate_work(size_t word_size) {
   assert_lock_strong(_lock);
 #ifdef ASSERT
   if (Metadebug::test_metadata_failure()) {
     return NULL;
   }
 #endif
   // Is there space in the current chunk?
   MetaWord* result = NULL;
   // For DumpSharedSpaces, only allocate out of the current chunk which is
   // never null because we gave it the size we wanted.   Caller reports out
   // of memory if this returns null.
   if (DumpSharedSpaces) {
     assert(current_chunk() != NULL, "should never happen");
     inc_used_metrics(word_size);
     return current_chunk()->allocate(word_size); // caller handles null result
   }
   if (current_chunk() != NULL) {
     result = current_chunk()->allocate(word_size);
   }
   if (result == NULL) {
     result = grow_and_allocate(word_size);
   }
   if (result > 0) {
     inc_used_metrics(word_size);
     assert(result != (MetaWord*) chunks_in_use(MediumIndex),
            "Head of the list is being allocated");
   }
   return result;
 }
 void SpaceManager::verify() {
   // If there are blocks in the dictionary, then
   // verfication of chunks does not work since
   // being in the dictionary alters a chunk.
   if (block_freelists()->total_size() == 0) {
     for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) {
       Metachunk* curr = chunks_in_use(i);
       while (curr != NULL) {
         curr->verify();
         verify_chunk_size(curr);
         curr = curr->next();
       }
     }
   }
 }
 void SpaceManager::verify_chunk_size(Metachunk* chunk) {
   assert(is_humongous(chunk->word_size()) ||
          chunk->word_size() == medium_chunk_size() ||
          chunk->word_size() == small_chunk_size() ||
          chunk->word_size() == specialized_chunk_size(),
          "Chunk size is wrong");
   return;
 }
 #ifdef ASSERT
 void SpaceManager::verify_allocated_blocks_words() {
   // Verification is only guaranteed at a safepoint.
   assert(SafepointSynchronize::is_at_safepoint() || !Universe::is_fully_initialized(),
     "Verification can fail if the applications is running");
   assert(allocated_blocks_words() == sum_used_in_chunks_in_use(),
     err_msg("allocation total is not consistent " SIZE_FORMAT
             " vs " SIZE_FORMAT,
             allocated_blocks_words(), sum_used_in_chunks_in_use()));
 }
 #endif
 void SpaceManager::dump(outputStream* const out) const {
   size_t curr_total = 0;
   size_t waste = 0;
   uint i = 0;
   size_t used = 0;
   size_t capacity = 0;
   // Add up statistics for all chunks in this SpaceManager.
   for (ChunkIndex index = ZeroIndex;
        index < NumberOfInUseLists;
        index = next_chunk_index(index)) {
     for (Metachunk* curr = chunks_in_use(index);
          curr != NULL;
          curr = curr->next()) {
       out->print("%d) ", i++);
       curr->print_on(out);
       if (TraceMetadataChunkAllocation && Verbose) {
         block_freelists()->print_on(out);
       }
       curr_total += curr->word_size();
       used += curr->used_word_size();
       capacity += curr->capacity_word_size();
       waste += curr->free_word_size() + curr->overhead();;
     }
   }
   size_t free = current_chunk() == NULL ? 0 : current_chunk()->free_word_size();
   // Free space isn't wasted.
   waste -= free;
   out->print_cr("total of all chunks "  SIZE_FORMAT " used " SIZE_FORMAT
                 " free " SIZE_FORMAT " capacity " SIZE_FORMAT
                 " waste " SIZE_FORMAT, curr_total, used, free, capacity, waste);
 }
 #ifndef PRODUCT
 void SpaceManager::mangle_freed_chunks() {
   for (ChunkIndex index = ZeroIndex;
        index < NumberOfInUseLists;
        index = next_chunk_index(index)) {
     for (Metachunk* curr = chunks_in_use(index);
          curr != NULL;
          curr = curr->next()) {
       curr->mangle();
     }
   }
 }
 #endif // PRODUCT
 // MetaspaceAux
 size_t MetaspaceAux::_allocated_capacity_words = 0;
 size_t MetaspaceAux::_allocated_used_words = 0;
 size_t MetaspaceAux::free_bytes() {
   size_t result = 0;
   if (Metaspace::class_space_list() != NULL) {
     result = result + Metaspace::class_space_list()->free_bytes();
   }
   if (Metaspace::space_list() != NULL) {
     result = result + Metaspace::space_list()->free_bytes();
   }
   return result;
 }
 void MetaspaceAux::dec_capacity(size_t words) {
   assert_lock_strong(SpaceManager::expand_lock());
   assert(words <= _allocated_capacity_words,
     err_msg("About to decrement below 0: words " SIZE_FORMAT
             " is greater than _allocated_capacity_words " SIZE_FORMAT,
             words, _allocated_capacity_words));
   _allocated_capacity_words = _allocated_capacity_words - words;
 }
 void MetaspaceAux::inc_capacity(size_t words) {
   assert_lock_strong(SpaceManager::expand_lock());
   // Needs to be atomic
   _allocated_capacity_words = _allocated_capacity_words + words;
 }
 void MetaspaceAux::dec_used(size_t words) {
   assert(words <= _allocated_used_words,
     err_msg("About to decrement below 0: words " SIZE_FORMAT
             " is greater than _allocated_used_words " SIZE_FORMAT,
             words, _allocated_used_words));
   // For CMS deallocation of the Metaspaces occurs during the
   // sweep which is a concurrent phase.  Protection by the expand_lock()
   // is not enough since allocation is on a per Metaspace basis
   // and protected by the Metaspace lock.
   jlong minus_words = (jlong) - (jlong) words;
   Atomic::add_ptr(minus_words, &_allocated_used_words);
 }
 void MetaspaceAux::inc_used(size_t words) {
   // _allocated_used_words tracks allocations for
   // each piece of metadata.  Those allocations are
   // generally done concurrently by different application
   // threads so must be done atomically.
   Atomic::add_ptr(words, &_allocated_used_words);
 }
 size_t MetaspaceAux::used_bytes_slow(Metaspace::MetadataType mdtype) {
   size_t used = 0;
   ClassLoaderDataGraphMetaspaceIterator iter;
   while (iter.repeat()) {
     Metaspace* msp = iter.get_next();
     // Sum allocated_blocks_words for each metaspace
     if (msp != NULL) {
       used += msp->used_words_slow(mdtype);
     }
   }
   return used * BytesPerWord;
 }
 size_t MetaspaceAux::free_in_bytes(Metaspace::MetadataType mdtype) {
   size_t free = 0;
   ClassLoaderDataGraphMetaspaceIterator iter;
   while (iter.repeat()) {
     Metaspace* msp = iter.get_next();
     if (msp != NULL) {
       free += msp->free_words(mdtype);
     }
   }
   return free * BytesPerWord;
 }
 size_t MetaspaceAux::capacity_bytes_slow(Metaspace::MetadataType mdtype) {
   // Don't count the space in the freelists.  That space will be
   // added to the capacity calculation as needed.
   size_t capacity = 0;
   ClassLoaderDataGraphMetaspaceIterator iter;
   while (iter.repeat()) {
     Metaspace* msp = iter.get_next();
     if (msp != NULL) {
       capacity += msp->capacity_words_slow(mdtype);
     }
   }
   return capacity * BytesPerWord;
 }
 size_t MetaspaceAux::reserved_in_bytes(Metaspace::MetadataType mdtype) {
   size_t reserved = (mdtype == Metaspace::ClassType) ?
                        Metaspace::class_space_list()->virtual_space_total() :
                        Metaspace::space_list()->virtual_space_total();
   return reserved * BytesPerWord;
 }
 size_t MetaspaceAux::min_chunk_size() { return Metaspace::first_chunk_word_size(); }
 size_t MetaspaceAux::free_chunks_total(Metaspace::MetadataType mdtype) {
   ChunkManager* chunk = (mdtype == Metaspace::ClassType) ?
                             Metaspace::class_space_list()->chunk_manager() :
                             Metaspace::space_list()->chunk_manager();
   chunk->slow_verify();
   return chunk->free_chunks_total();
 }
 size_t MetaspaceAux::free_chunks_total_in_bytes(Metaspace::MetadataType mdtype) {
   return free_chunks_total(mdtype) * BytesPerWord;
 }
 size_t MetaspaceAux::free_chunks_total() {
   return free_chunks_total(Metaspace::ClassType) +
          free_chunks_total(Metaspace::NonClassType);
 }
 size_t MetaspaceAux::free_chunks_total_in_bytes() {
   return free_chunks_total() * BytesPerWord;
 }
 void MetaspaceAux::print_metaspace_change(size_t prev_metadata_used) {
   gclog_or_tty->print(", [Metaspace:");
   if (PrintGCDetails && Verbose) {
     gclog_or_tty->print(" "  SIZE_FORMAT
                         "->" SIZE_FORMAT
                         "("  SIZE_FORMAT ")",
                         prev_metadata_used,
                         allocated_capacity_bytes(),
                         reserved_in_bytes());
   } else {
     gclog_or_tty->print(" "  SIZE_FORMAT "K"
                         "->" SIZE_FORMAT "K"
                         "("  SIZE_FORMAT "K)",
                         prev_metadata_used / K,
                         allocated_capacity_bytes() / K,
                         reserved_in_bytes()/ K);
   }
   gclog_or_tty->print("]");
 }
 // This is printed when PrintGCDetails
 void MetaspaceAux::print_on(outputStream* out) {
   Metaspace::MetadataType ct = Metaspace::ClassType;
   Metaspace::MetadataType nct = Metaspace::NonClassType;
   out->print_cr(" Metaspace total "
                 SIZE_FORMAT "K, used " SIZE_FORMAT "K,"
                 " reserved " SIZE_FORMAT "K",
                 allocated_capacity_bytes()/K, allocated_used_bytes()/K, reserved_in_bytes()/K);
 #if 0
 // The calls to capacity_bytes_slow() and used_bytes_slow() cause
 // lock ordering assertion failures with some collectors.  Do
 // not include this code until the lock ordering is fixed.
   if (PrintGCDetails && Verbose) {
     out->print_cr("  data space     "
                   SIZE_FORMAT "K, used " SIZE_FORMAT "K,"
                   " reserved " SIZE_FORMAT "K",
                   capacity_bytes_slow(nct)/K, used_bytes_slow(nct)/K, reserved_in_bytes(nct)/K);
     out->print_cr("  class space    "
                   SIZE_FORMAT "K, used " SIZE_FORMAT "K,"
                   " reserved " SIZE_FORMAT "K",
                   capacity_bytes_slow(ct)/K, used_bytes_slow(ct)/K, reserved_in_bytes(ct)/K);
   }
 #endif
 }
 // Print information for class space and data space separately.
 // This is almost the same as above.
 void MetaspaceAux::print_on(outputStream* out, Metaspace::MetadataType mdtype) {
   size_t free_chunks_capacity_bytes = free_chunks_total_in_bytes(mdtype);
   size_t capacity_bytes = capacity_bytes_slow(mdtype);
   size_t used_bytes = used_bytes_slow(mdtype);
   size_t free_bytes = free_in_bytes(mdtype);
   size_t used_and_free = used_bytes + free_bytes +
                            free_chunks_capacity_bytes;
   out->print_cr("  Chunk accounting: used in chunks " SIZE_FORMAT
              "K + unused in chunks " SIZE_FORMAT "K  + "
              " capacity in free chunks " SIZE_FORMAT "K = " SIZE_FORMAT
              "K  capacity in allocated chunks " SIZE_FORMAT "K",
              used_bytes / K,
              free_bytes / K,
              free_chunks_capacity_bytes / K,
              used_and_free / K,
              capacity_bytes / K);
   // Accounting can only be correct if we got the values during a safepoint
   assert(!SafepointSynchronize::is_at_safepoint() || used_and_free == capacity_bytes, "Accounting is wrong");
 }
 // Print total fragmentation for class and data metaspaces separately
 void MetaspaceAux::print_waste(outputStream* out) {
   size_t specialized_waste = 0, small_waste = 0, medium_waste = 0, large_waste = 0;
   size_t specialized_count = 0, small_count = 0, medium_count = 0, large_count = 0;
   size_t cls_specialized_waste = 0, cls_small_waste = 0, cls_medium_waste = 0, cls_large_waste = 0;
   size_t cls_specialized_count = 0, cls_small_count = 0, cls_medium_count = 0, cls_large_count = 0;
   ClassLoaderDataGraphMetaspaceIterator iter;
   while (iter.repeat()) {
     Metaspace* msp = iter.get_next();
     if (msp != NULL) {
       specialized_waste += msp->vsm()->sum_waste_in_chunks_in_use(SpecializedIndex);
       specialized_count += msp->vsm()->sum_count_in_chunks_in_use(SpecializedIndex);
       small_waste += msp->vsm()->sum_waste_in_chunks_in_use(SmallIndex);
       small_count += msp->vsm()->sum_count_in_chunks_in_use(SmallIndex);
       medium_waste += msp->vsm()->sum_waste_in_chunks_in_use(MediumIndex);
       medium_count += msp->vsm()->sum_count_in_chunks_in_use(MediumIndex);
       large_waste += msp->vsm()->sum_waste_in_chunks_in_use(HumongousIndex);
       large_count += msp->vsm()->sum_count_in_chunks_in_use(HumongousIndex);
       cls_specialized_waste += msp->class_vsm()->sum_waste_in_chunks_in_use(SpecializedIndex);
       cls_specialized_count += msp->class_vsm()->sum_count_in_chunks_in_use(SpecializedIndex);
       cls_small_waste += msp->class_vsm()->sum_waste_in_chunks_in_use(SmallIndex);
       cls_small_count += msp->class_vsm()->sum_count_in_chunks_in_use(SmallIndex);
       cls_medium_waste += msp->class_vsm()->sum_waste_in_chunks_in_use(MediumIndex);
       cls_medium_count += msp->class_vsm()->sum_count_in_chunks_in_use(MediumIndex);
       cls_large_waste += msp->class_vsm()->sum_waste_in_chunks_in_use(HumongousIndex);
       cls_large_count += msp->class_vsm()->sum_count_in_chunks_in_use(HumongousIndex);
     }
   }
   out->print_cr("Total fragmentation waste (words) doesn't count free space");
   out->print_cr("  data: " SIZE_FORMAT " specialized(s) " SIZE_FORMAT ", "
                         SIZE_FORMAT " small(s) " SIZE_FORMAT ", "
                         SIZE_FORMAT " medium(s) " SIZE_FORMAT,
              specialized_count, specialized_waste, small_count,
              small_waste, medium_count, medium_waste);
   out->print_cr(" class: " SIZE_FORMAT " specialized(s) " SIZE_FORMAT ", "
                            SIZE_FORMAT " small(s) " SIZE_FORMAT,
              cls_specialized_count, cls_specialized_waste,
              cls_small_count, cls_small_waste);
 }
 // Dump global metaspace things from the end of ClassLoaderDataGraph
 void MetaspaceAux::dump(outputStream* out) {
   out->print_cr("All Metaspace:");
   out->print("data space: "); print_on(out, Metaspace::NonClassType);
   out->print("class space: "); print_on(out, Metaspace::ClassType);
   print_waste(out);
 }
 void MetaspaceAux::verify_free_chunks() {
   Metaspace::space_list()->chunk_manager()->verify();
   Metaspace::class_space_list()->chunk_manager()->verify();
 }
 void MetaspaceAux::verify_capacity() {
 #ifdef ASSERT
   size_t running_sum_capacity_bytes = allocated_capacity_bytes();
   // For purposes of the running sum of used, verify against capacity
   size_t capacity_in_use_bytes = capacity_bytes_slow();
   assert(running_sum_capacity_bytes == capacity_in_use_bytes,
     err_msg("allocated_capacity_words() * BytesPerWord " SIZE_FORMAT
             " capacity_bytes_slow()" SIZE_FORMAT,
             running_sum_capacity_bytes, capacity_in_use_bytes));
 #endif
 }
 void MetaspaceAux::verify_used() {
 #ifdef ASSERT
   size_t running_sum_used_bytes = allocated_used_bytes();
   // For purposes of the running sum of used, verify against capacity
   size_t used_in_use_bytes = used_bytes_slow();
   assert(allocated_used_bytes() == used_in_use_bytes,
     err_msg("allocated_used_bytes() " SIZE_FORMAT
             " used_bytes_slow()()" SIZE_FORMAT,
             allocated_used_bytes(), used_in_use_bytes));
 #endif
 }
 void MetaspaceAux::verify_metrics() {
   verify_capacity();
   verify_used();
 }
 // Metaspace methods
 size_t Metaspace::_first_chunk_word_size = 0;
 size_t Metaspace::_first_class_chunk_word_size = 0;
 Metaspace::Metaspace(Mutex* lock, MetaspaceType type) {
   initialize(lock, type);
 }
 Metaspace::~Metaspace() {
   delete _vsm;
   delete _class_vsm;
 }
 VirtualSpaceList* Metaspace::_space_list = NULL;
 VirtualSpaceList* Metaspace::_class_space_list = NULL;
 #define VIRTUALSPACEMULTIPLIER 2
 void Metaspace::global_initialize() {
   // Initialize the alignment for shared spaces.
   int max_alignment = os::vm_page_size();
   MetaspaceShared::set_max_alignment(max_alignment);
   if (DumpSharedSpaces) {
     SharedReadOnlySize = align_size_up(SharedReadOnlySize, max_alignment);
     SharedReadWriteSize = align_size_up(SharedReadWriteSize, max_alignment);
     SharedMiscDataSize  = align_size_up(SharedMiscDataSize, max_alignment);
     SharedMiscCodeSize  = align_size_up(SharedMiscCodeSize, max_alignment);
     // Initialize with the sum of the shared space sizes.  The read-only
     // and read write metaspace chunks will be allocated out of this and the
     // remainder is the misc code and data chunks.
     size_t total = align_size_up(SharedReadOnlySize + SharedReadWriteSize +
                                  SharedMiscDataSize + SharedMiscCodeSize,
                                  os::vm_allocation_granularity());
     size_t word_size = total/wordSize;
     _space_list = new VirtualSpaceList(word_size);
   } else {
     // If using shared space, open the file that contains the shared space
     // and map in the memory before initializing the rest of metaspace (so
     // the addresses don't conflict)
     if (UseSharedSpaces) {
       FileMapInfo* mapinfo = new FileMapInfo();
       memset(mapinfo, 0, sizeof(FileMapInfo));
       // Open the shared archive file, read and validate the header. If
       // initialization fails, shared spaces [UseSharedSpaces] are
       // disabled and the file is closed.
       // Map in spaces now also
       if (mapinfo->initialize() && MetaspaceShared::map_shared_spaces(mapinfo)) {
         FileMapInfo::set_current_info(mapinfo);
       } else {
         assert(!mapinfo->is_open() && !UseSharedSpaces,
                "archive file not closed or shared spaces not disabled.");
       }
     }
     // Initialize these before initializing the VirtualSpaceList
     _first_chunk_word_size = InitialBootClassLoaderMetaspaceSize / BytesPerWord;
     _first_chunk_word_size = align_word_size_up(_first_chunk_word_size);
     // Make the first class chunk bigger than a medium chunk so it's not put
     // on the medium chunk list.   The next chunk will be small and progress
     // from there.  This size calculated by -version.
     _first_class_chunk_word_size = MIN2((size_t)MediumChunk*6,
                                        (ClassMetaspaceSize/BytesPerWord)*2);
     _first_class_chunk_word_size = align_word_size_up(_first_class_chunk_word_size);
     // Arbitrarily set the initial virtual space to a multiple
     // of the boot class loader size.
     size_t word_size = VIRTUALSPACEMULTIPLIER * first_chunk_word_size();
     // Initialize the list of virtual spaces.
     _space_list = new VirtualSpaceList(word_size);
   }
 }
 // For UseCompressedKlassPointers the class space is reserved as a piece of the
 // Java heap because the compression algorithm is the same for each.  The
 // argument passed in is at the top of the compressed space
 void Metaspace::initialize_class_space(ReservedSpace rs) {
   // The reserved space size may be bigger because of alignment, esp with UseLargePages
   assert(rs.size() >= ClassMetaspaceSize,
          err_msg(SIZE_FORMAT " != " UINTX_FORMAT, rs.size(), ClassMetaspaceSize));
   _class_space_list = new VirtualSpaceList(rs);
 }
 void Metaspace::initialize(Mutex* lock,
                            MetaspaceType type) {
   assert(space_list() != NULL,
     "Metadata VirtualSpaceList has not been initialized");
   _vsm = new SpaceManager(lock, space_list());
   if (_vsm == NULL) {
     return;
   }
   size_t word_size;
   size_t class_word_size;
   vsm()->get_initial_chunk_sizes(type,
                                  &word_size,
                                  &class_word_size);
   assert(class_space_list() != NULL,
     "Class VirtualSpaceList has not been initialized");
   // Allocate SpaceManager for classes.
   _class_vsm = new SpaceManager(lock, class_space_list());
   if (_class_vsm == NULL) {
     return;
   }
   MutexLockerEx cl(SpaceManager::expand_lock(), Mutex::_no_safepoint_check_flag);
   // Allocate chunk for metadata objects
   Metachunk* new_chunk =
      space_list()->get_initialization_chunk(word_size,
                                             vsm()->medium_chunk_bunch());
   assert(!DumpSharedSpaces || new_chunk != NULL, "should have enough space for both chunks");
   if (new_chunk != NULL) {
     // Add to this manager's list of chunks in use and current_chunk().
     vsm()->add_chunk(new_chunk, true);
   }
   // Allocate chunk for class metadata objects
   Metachunk* class_chunk =
      class_space_list()->get_initialization_chunk(class_word_size,
                                                   class_vsm()->medium_chunk_bunch());
   if (class_chunk != NULL) {
     class_vsm()->add_chunk(class_chunk, true);
   }
 }
 size_t Metaspace::align_word_size_up(size_t word_size) {
   size_t byte_size = word_size * wordSize;
   return ReservedSpace::allocation_align_size_up(byte_size) / wordSize;
 }
 MetaWord* Metaspace::allocate(size_t word_size, MetadataType mdtype) {
   // DumpSharedSpaces doesn't use class metadata area (yet)
   if (mdtype == ClassType && !DumpSharedSpaces) {
     return  class_vsm()->allocate(word_size);
   } else {
     return  vsm()->allocate(word_size);
   }
 }
 MetaWord* Metaspace::expand_and_allocate(size_t word_size, MetadataType mdtype) {
   MetaWord* result;
   MetaspaceGC::set_expand_after_GC(true);
   size_t before_inc = MetaspaceGC::capacity_until_GC();
   size_t delta_bytes = MetaspaceGC::delta_capacity_until_GC(word_size) * BytesPerWord;
   MetaspaceGC::inc_capacity_until_GC(delta_bytes);
   if (PrintGCDetails && Verbose) {
     gclog_or_tty->print_cr("Increase capacity to GC from " SIZE_FORMAT
       " to " SIZE_FORMAT, before_inc, MetaspaceGC::capacity_until_GC());
   }
   result = allocate(word_size, mdtype);
   return result;
 }
 // Space allocated in the Metaspace.  This may
 // be across several metadata virtual spaces.
 char* Metaspace::bottom() const {
   assert(DumpSharedSpaces, "only useful and valid for dumping shared spaces");
   return (char*)vsm()->current_chunk()->bottom();
 }
 size_t Metaspace::used_words_slow(MetadataType mdtype) const {
   // return vsm()->allocated_used_words();
   return mdtype == ClassType ? class_vsm()->sum_used_in_chunks_in_use() :
                                vsm()->sum_used_in_chunks_in_use();  // includes overhead!
 }
 size_t Metaspace::free_words(MetadataType mdtype) const {
   return mdtype == ClassType ? class_vsm()->sum_free_in_chunks_in_use() :
                                vsm()->sum_free_in_chunks_in_use();
 }
 // Space capacity in the Metaspace.  It includes
 // space in the list of chunks from which allocations
 // have been made. Don't include space in the global freelist and
 // in the space available in the dictionary which
 // is already counted in some chunk.
 size_t Metaspace::capacity_words_slow(MetadataType mdtype) const {
   return mdtype == ClassType ? class_vsm()->sum_capacity_in_chunks_in_use() :
                                vsm()->sum_capacity_in_chunks_in_use();
 }
 size_t Metaspace::used_bytes_slow(MetadataType mdtype) const {
   return used_words_slow(mdtype) * BytesPerWord;
 }
 size_t Metaspace::capacity_bytes_slow(MetadataType mdtype) const {
   return capacity_words_slow(mdtype) * BytesPerWord;
 }
 void Metaspace::deallocate(MetaWord* ptr, size_t word_size, bool is_class) {
   if (SafepointSynchronize::is_at_safepoint()) {
     assert(Thread::current()->is_VM_thread(), "should be the VM thread");
     // Don't take Heap_lock
     MutexLockerEx ml(vsm()->lock(), Mutex::_no_safepoint_check_flag);
     if (word_size < TreeChunk<Metablock, FreeList>::min_size()) {
       // Dark matter.  Too small for dictionary.
 #ifdef ASSERT
       Copy::fill_to_words((HeapWord*)ptr, word_size, 0xf5f5f5f5);
 #endif
       return;
     }
     if (is_class) {
        class_vsm()->deallocate(ptr, word_size);
     } else {
       vsm()->deallocate(ptr, word_size);
     }
   } else {
     MutexLockerEx ml(vsm()->lock(), Mutex::_no_safepoint_check_flag);
     if (word_size < TreeChunk<Metablock, FreeList>::min_size()) {
       // Dark matter.  Too small for dictionary.
 #ifdef ASSERT
       Copy::fill_to_words((HeapWord*)ptr, word_size, 0xf5f5f5f5);
 #endif
       return;
     }
     if (is_class) {
       class_vsm()->deallocate(ptr, word_size);
     } else {
       vsm()->deallocate(ptr, word_size);
     }
   }
 }
 Metablock* Metaspace::allocate(ClassLoaderData* loader_data, size_t word_size,
                               bool read_only, MetadataType mdtype, TRAPS) {
   if (HAS_PENDING_EXCEPTION) {
     assert(false, "Should not allocate with exception pending");
     return NULL;  // caller does a CHECK_NULL too
   }
   // SSS: Should we align the allocations and make sure the sizes are aligned.
   MetaWord* result = NULL;
   assert(loader_data != NULL, "Should never pass around a NULL loader_data. "
         "ClassLoaderData::the_null_class_loader_data() should have been used.");
   // Allocate in metaspaces without taking out a lock, because it deadlocks
   // with the SymbolTable_lock.  Dumping is single threaded for now.  We'll have
   // to revisit this for application class data sharing.
   if (DumpSharedSpaces) {
     if (read_only) {
       result = loader_data->ro_metaspace()->allocate(word_size, NonClassType);
     } else {
       result = loader_data->rw_metaspace()->allocate(word_size, NonClassType);
     }
     if (result == NULL) {
       report_out_of_shared_space(read_only ? SharedReadOnly : SharedReadWrite);
     }
     return Metablock::initialize(result, word_size);
   }
   result = loader_data->metaspace_non_null()->allocate(word_size, mdtype);
   if (result == NULL) {
     // Try to clean out some memory and retry.
     result =
       Universe::heap()->collector_policy()->satisfy_failed_metadata_allocation(
         loader_data, word_size, mdtype);
     // If result is still null, we are out of memory.
     if (result == NULL) {
       if (Verbose && TraceMetadataChunkAllocation) {
         gclog_or_tty->print_cr("Metaspace allocation failed for size "
           SIZE_FORMAT, word_size);
         if (loader_data->metaspace_or_null() != NULL) loader_data->metaspace_or_null()->dump(gclog_or_tty);
         MetaspaceAux::dump(gclog_or_tty);
       }
       // -XX:+HeapDumpOnOutOfMemoryError and -XX:OnOutOfMemoryError support
       report_java_out_of_memory("Metadata space");
       if (JvmtiExport::should_post_resource_exhausted()) {
         JvmtiExport::post_resource_exhausted(
             JVMTI_RESOURCE_EXHAUSTED_OOM_ERROR,
             "Metadata space");
       }
       THROW_OOP_0(Universe::out_of_memory_error_perm_gen());
     }
   }
   return Metablock::initialize(result, word_size);
 }
 void Metaspace::purge() {
   MutexLockerEx cl(SpaceManager::expand_lock(),
                    Mutex::_no_safepoint_check_flag);
   space_list()->purge();
   class_space_list()->purge();
 }
 void Metaspace::print_on(outputStream* out) const {
   // Print both class virtual space counts and metaspace.
   if (Verbose) {
       vsm()->print_on(out);
       class_vsm()->print_on(out);
   }
 }
 bool Metaspace::contains(const void * ptr) {
   if (MetaspaceShared::is_in_shared_space(ptr)) {
     return true;
   }
   // This is checked while unlocked.  As long as the virtualspaces are added
   // at the end, the pointer will be in one of them.  The virtual spaces
   // aren't deleted presently.  When they are, some sort of locking might
   // be needed.  Note, locking this can cause inversion problems with the
   // caller in MetaspaceObj::is_metadata() function.
   return space_list()->contains(ptr) ||
          class_space_list()->contains(ptr);
 }
 void Metaspace::verify() {
   vsm()->verify();
   class_vsm()->verify();
 }
 void Metaspace::dump(outputStream* const out) const {
   out->print_cr("\nVirtual space manager: " INTPTR_FORMAT, vsm());
   vsm()->dump(out);
   out->print_cr("\nClass space manager: " INTPTR_FORMAT, class_vsm());
   class_vsm()->dump(out);
 }

Mercurial > jdk8-mips64-public > hotspot / annotate

src/share/vm/memory/metaspace.cpp@601183f604b2 (annotated)

src/share/vm/memory/metaspace.cpp