diff -r caf5eb7dd4a7 -r 882756847a04 hotspot/src/share/vm/memory/metaspace.cpp --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/hotspot/src/share/vm/memory/metaspace.cpp Sat Sep 01 13:25:18 2012 -0400 @@ -0,0 +1,2999 @@ +/* + * Copyright (c) 2011, 2012, 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/collectorPolicy.hpp" +#include "memory/filemap.hpp" +#include "memory/freeList.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 "services/memTracker.hpp" +#include "utilities/copy.hpp" +#include "utilities/debug.hpp" + +// Define this macro to deallocate Metablock. If not defined, +// blocks are not yet deallocated and are only mangled. +#undef DEALLOCATE_BLOCKS + +// Easily recognizable patterns +// These patterns can be the same in 32bit or 64bit since +// they only have to be easily recognizable. +const void* metaspace_allocation_leader = (void*) 0X11111111; +const void* metaspace_allocation_trailer = (void*) 0X77777777; + +// 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; +const size_t metadata_chunk_initialize = 0xf7f7f7f7; +const size_t metadata_deallocate = 0xf5f5f5f5; +const size_t metadata_space_manager_allocate = 0xf3f3f3f3; + +MetaWord* last_allocated = 0; + +// Used in declarations in SpaceManager and ChunkManager +enum ChunkIndex { + SmallIndex = 0, + MediumIndex = 1, + HumongousIndex = 2, + NumberOfFreeLists = 3 +}; + +static ChunkIndex next_chunk_index(ChunkIndex i) { + assert(i < NumberOfFreeLists, "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. +// +// Future modification +// +// The Metachunk can conceivable be replaced by the Chunk in +// allocation.hpp. Note that the latter Chunk is the space for +// allocation (allocations from the chunk are out of the space in +// the Chunk after the header for the Chunk) where as Metachunks +// point to space in a VirtualSpace. To replace Metachunks with +// Chunks, change Chunks so that they can be allocated out of a VirtualSpace. +// + +// Metablock are the unit of allocation from a Chunk. It contains +// the size of the requested allocation in a debug build. +// Also in a debug build it has a marker before and after the +// body of the block. The address of the body is the address returned +// by the allocation. +// +// Layout in a debug build. In a product build only the body is present. +// +// +-----------+-----------+------------+ +-----------+ +// | word size | leader | body | ... | trailer | +// +-----------+-----------+------------+ +-----------+ +// +// A Metablock may be reused by its SpaceManager but are never moved between +// SpaceManagers. There is no explicit link to the Metachunk +// from which it was allocated. Metablock are not deallocated, rather +// the Metachunk it is a part of will be deallocated when it's +// associated class loader is collected. +// +// When the word size of a block is passed in to the deallocation +// call the word size no longer needs to be part of a Metablock. + +class Metablock { + friend class VMStructs; + private: + // Used to align the allocation (see below) and for debugging. +#ifdef ASSERT + struct { + size_t _word_size; + void* _leader; + } _header; + void* _data[1]; +#endif + static size_t _overhead; + +#ifdef ASSERT + void set_word_size(size_t v) { _header._word_size = v; } + void* leader() { return _header._leader; } + void* trailer() { + jlong index = (jlong) _header._word_size - sizeof(_header)/BytesPerWord - 1; + assert(index > 0, err_msg("Bad indexling of trailer %d", index)); + void** ptr = &_data[index]; + return *ptr; + } + void set_leader(void* v) { _header._leader = v; } + void set_trailer(void* v) { + void** ptr = &_data[_header._word_size - sizeof(_header)/BytesPerWord - 1]; + *ptr = v; + } + public: + size_t word_size() { return _header._word_size; } +#endif + public: + + static Metablock* initialize(MetaWord* p, size_t word_size); + + // This places the body of the block at a 2 word boundary + // because every block starts on a 2 word boundary. Work out + // how to make the body on a 2 word boundary if the block + // starts on a arbitrary boundary. JJJ + +#ifdef ASSERT + MetaWord* data() { return (MetaWord*) &_data[0]; } +#else + MetaWord* data() { return (MetaWord*) this; } +#endif + static Metablock* metablock_from_data(MetaWord* p) { +#ifdef ASSERT + size_t word_offset = offset_of(Metablock, _data)/BytesPerWord; + Metablock* result = (Metablock*) (p - word_offset); + return result; +#else + return (Metablock*) p; +#endif + } + + static size_t overhead() { return _overhead; } + void verify(); +}; + +// Metachunk - Quantum of allocation from a Virtualspace +// Metachunks are reused (when freed are put on a global freelist) and +// have no permanent association to a SpaceManager. + +// +--------------+ <- end +// | | --+ ---+ +// | | | free | +// | | | | +// | | | | capacity +// | | | | +// | | <- top --+ | +// | | ---+ | +// | | | used | +// | | | | +// | | | | +// +--------------+ <- bottom ---+ ---+ + +class Metachunk VALUE_OBJ_CLASS_SPEC { + // link to support lists of chunks + Metachunk* _next; + + MetaWord* _bottom; + MetaWord* _end; + MetaWord* _top; + size_t _word_size; + + // Metachunks are allocated out of a MetadataVirtualSpace and + // and use some of its space to describe itself (plus alignment + // considerations). Metadata is allocated in the rest of the chunk. + // This size is the overhead of maintaining the Metachunk within + // the space. + static size_t _overhead; + + void set_bottom(MetaWord* v) { _bottom = v; } + void set_end(MetaWord* v) { _end = v; } + void set_top(MetaWord* v) { _top = v; } + void set_word_size(size_t v) { _word_size = v; } + public: + + // Used to add a Metachunk to a list of Metachunks + void set_next(Metachunk* v) { _next = v; assert(v != this, "Boom");} + + Metablock* allocate(size_t word_size); + static Metachunk* initialize(MetaWord* ptr, size_t word_size); + + // Accessors + Metachunk* next() const { return _next; } + MetaWord* bottom() const { return _bottom; } + MetaWord* end() const { return _end; } + MetaWord* top() const { return _top; } + size_t word_size() const { return _word_size; } + static size_t overhead() { return _overhead; } + + // Reset top to bottom so chunk can be reused. + void reset_empty() { _top = (_bottom + _overhead); } + bool is_empty() { return _top == (_bottom + _overhead); } + + // used (has been allocated) + // free (available for future allocations) + // capacity (total size of chunk) + size_t used_word_size(); + size_t free_word_size(); + size_t capacity_word_size(); + +#ifdef ASSERT + void mangle() { + // Mangle the payload of the chunk and not the links that + // maintain list of chunks. + HeapWord* start = (HeapWord*)(bottom() + overhead()); + size_t word_size = capacity_word_size() - overhead(); + Copy::fill_to_words(start, word_size, metadata_chunk_initialize); + } +#endif // ASSERT + + void print_on(outputStream* st) const; + void verify(); +}; + + +// Pointer to list of Metachunks. +class ChunkList VALUE_OBJ_CLASS_SPEC { + // List of free chunks + Metachunk* _head; + + public: + // Constructor + ChunkList() : _head(NULL) {} + + // Accessors + Metachunk* head() { return _head; } + void set_head(Metachunk* v) { _head = v; } + + // Link at head of the list + void add_at_head(Metachunk* head, Metachunk* tail); + void add_at_head(Metachunk* head); + + size_t sum_list_size(); + size_t sum_list_count(); + size_t sum_list_capacity(); +}; + +// 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. + // SmallChunk + // MediumChunk + // HumongousChunk + ChunkList _free_chunks[3]; + + // 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 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); + + // 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); + } + ChunkList* free_medium_chunks() { return &_free_chunks[1]; } + ChunkList* free_small_chunks() { return &_free_chunks[0]; } + ChunkList* free_humongous_chunks() { return &_free_chunks[2]; } + + 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 locked_verify(); + void verify_free_chunks_total(); + + void locked_print_free_chunks(outputStream* st); + void locked_print_sum_free_chunks(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 { +#ifdef DEALLOCATE_BLOCKS + BinaryTreeDictionary* _dictionary; +#endif + static Metablock* initialize_free_chunk(Metablock* block, size_t word_size); + +#ifdef DEALLOCATE_BLOCKS + // Accessors + BinaryTreeDictionary* dictionary() const { return _dictionary; } +#endif + + public: + BlockFreelist(); + ~BlockFreelist(); + + // Get and return a block to the free list + Metablock* get_block(size_t word_size); + void return_block(Metablock* block, size_t word_size); + + size_t totalSize() { +#ifdef DEALLOCATE_BLOCKS + if (dictionary() == NULL) { + return 0; + } else { + return dictionary()->totalSize(); + } +#else + return 0; +#endif + } + + void print_on(outputStream* st) const; +}; + +class VirtualSpaceNode : public CHeapObj { + friend class VirtualSpaceList; + + // Link to next VirtualSpaceNode + VirtualSpaceNode* _next; + + // total in the VirtualSpace + MemRegion _reserved; + ReservedSpace _rs; + VirtualSpace _virtual_space; + MetaWord* _top; + + // 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(); } + + public: + + VirtualSpaceNode(size_t byte_size); + VirtualSpaceNode(ReservedSpace rs) : _top(NULL), _next(NULL), _rs(rs) {} + ~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 virtual space + 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; } + + // used and capacity in this single entry in the list + size_t used_words_in_vs() const; + size_t capacity_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); + + // Debug support + static void verify_virtual_space_total(); + static void verify_virtual_space_count(); + void mangle(); + + 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) { + // This allocates memory with mmap. For DumpSharedspaces, allocate the + // space at low memory so that other shared images don't conflict. + // This is the same address as memory needed for UseCompressedOops but + // compressed oops don't work with CDS (offsets in metadata are wrong), so + // borrow the same address. + if (DumpSharedSpaces) { + char* shared_base = (char*)HeapBaseMinAddress; + _rs = ReservedSpace(byte_size, 0, false, shared_base, 0); + if (_rs.is_reserved()) { + assert(_rs.base() == shared_base, "should match"); + } else { + // If we are dumping the heap, then allocate a wasted block of address + // space in order to push the heap to a lower address. This extra + // address range allows for other (or larger) libraries to be loaded + // without them occupying the space required for the shared spaces. + uintx reserved = 0; + uintx block_size = 64*1024*1024; + while (reserved < SharedDummyBlockSize) { + char* dummy = os::reserve_memory(block_size); + reserved += block_size; + } + _rs = ReservedSpace(byte_size); + } + MetaspaceShared::set_shared_rs(&_rs); + } else { + _rs = ReservedSpace(byte_size); + } + + MemTracker::record_virtual_memory_type((address)_rs.base(), mtClass); +} + +// 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 { + 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); + + Metachunk* get_new_chunk(size_t word_size, size_t grow_chunks_by_words); + + 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) { + Atomic::add_ptr(v, &_virtual_space_total); + } + + size_t virtual_space_count() { return _virtual_space_count; } + void inc_virtual_space_count() { + Atomic::inc_ptr(&_virtual_space_count); + } + + // 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 { + friend class Metaspace; + friend class Metadebug; + + private: + // protects allocations and contains. + Mutex* const _lock; + + // 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[NumberOfFreeLists]; + 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 _allocation_total; + + // 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; + + // 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); + + // Debugging support + void verify_chunks_in_use_index(ChunkIndex index, Metachunk* v) { + switch (index) { + case 0: + assert(v->word_size() == SmallChunk, "Not a SmallChunk"); + break; + case 1: + assert(v->word_size() == MediumChunk, "Not a MediumChunk"); + break; + case 2: + assert(v->word_size() > MediumChunk, "Not a HumongousChunk"); + break; + default: + assert(false, "Wrong list."); + } + } + + protected: + Mutex* lock() const { return _lock; } + + public: + SpaceManager(Mutex* lock, VirtualSpaceList* vs_list); + ~SpaceManager(); + + enum ChunkSizes { // in words. + SmallChunk = 512, + MediumChunk = 8 * K, + MediumChunkBunch = 4 * MediumChunk + }; + + // Accessors + size_t allocation_total() const { return _allocation_total; } + void inc_allocation_total(size_t v) { Atomic::add_ptr(v, &_allocation_total); } + static bool is_humongous(size_t word_size) { return word_size > MediumChunk; } + + static Mutex* expand_lock() { return _expand_lock; } + + 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); + + // Block allocation and deallocation. + // Allocates a block from the current chunk + MetaWord* allocate(size_t word_size); + + // Helper for allocations + Metablock* allocate_work(size_t word_size); + + // Returns a block to the per manager freelist + void deallocate(MetaWord* p); + + // 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. + Metablock* 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(); +#ifdef ASSERT + void mangle_freed_chunks(); + void verify_allocation_total(); +#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); + +#ifdef ASSERT +size_t Metablock::_overhead = + Chunk::aligned_overhead_size(sizeof(Metablock)) / BytesPerWord; +#else +size_t Metablock::_overhead = 0; +#endif +size_t Metachunk::_overhead = + Chunk::aligned_overhead_size(sizeof(Metachunk)) / BytesPerWord; + +// New blocks returned by the Metaspace are zero initialized. +// We should fix the constructors to not assume this instead. +Metablock* Metablock::initialize(MetaWord* p, size_t word_size) { + Metablock* result = (Metablock*) p; + + // Clear the memory + Copy::fill_to_aligned_words((HeapWord*)result, word_size); +#ifdef ASSERT + result->set_word_size(word_size); + // Check after work size is set. + result->set_leader((void*) metaspace_allocation_leader); + result->set_trailer((void*) metaspace_allocation_trailer); +#endif + return result; +} + +void Metablock::verify() { +#ifdef ASSERT + assert(leader() == metaspace_allocation_leader && + trailer() == metaspace_allocation_trailer, + "block has been corrupted"); +#endif +} + +// Metachunk methods + +Metachunk* Metachunk::initialize(MetaWord* ptr, size_t word_size) { + // Set bottom, top, and end. Allow space for the Metachunk itself + Metachunk* chunk = (Metachunk*) ptr; + + MetaWord* chunk_bottom = ptr + _overhead; + chunk->set_bottom(ptr); + chunk->set_top(chunk_bottom); + MetaWord* chunk_end = ptr + word_size; + assert(chunk_end > chunk_bottom, "Chunk must be too small"); + chunk->set_end(chunk_end); + chunk->set_next(NULL); + chunk->set_word_size(word_size); +#ifdef ASSERT + size_t data_word_size = pointer_delta(chunk_end, chunk_bottom, sizeof(MetaWord)); + Copy::fill_to_words((HeapWord*) chunk_bottom, data_word_size, metadata_chunk_initialize); +#endif + return chunk; +} + + +Metablock* Metachunk::allocate(size_t word_size) { + Metablock* result = NULL; + // If available, bump the pointer to allocate. + if (free_word_size() >= word_size) { + result = Metablock::initialize(_top, word_size); + _top = _top + word_size; + } +#ifdef ASSERT + assert(result == NULL || + result->word_size() == word_size, + "Block size is not set correctly"); +#endif + return result; +} + +// _bottom points to the start of the chunk including the overhead. +size_t Metachunk::used_word_size() { + return pointer_delta(_top, _bottom, sizeof(MetaWord)); +} + +size_t Metachunk::free_word_size() { + return pointer_delta(_end, _top, sizeof(MetaWord)); +} + +size_t Metachunk::capacity_word_size() { + return pointer_delta(_end, _bottom, sizeof(MetaWord)); +} + +void Metachunk::print_on(outputStream* st) const { + st->print_cr("Metachunk:" + " bottom " PTR_FORMAT " top " PTR_FORMAT + " end " PTR_FORMAT " size " SIZE_FORMAT, + bottom(), top(), end(), word_size()); +} + + +void Metachunk::verify() { +#ifdef ASSERT + // Cannot walk through the blocks unless the blocks have + // headers with sizes. + MetaWord* curr = bottom() + overhead(); + while (curr < top()) { + Metablock* block = (Metablock*) curr; + size_t word_size = block->word_size(); + block->verify(); + curr = curr + word_size; + } +#endif + return; +} + +// BlockFreelist methods + +#ifdef DEALLOCATE_BLOCKS +BlockFreelist::BlockFreelist() : _dictionary(NULL) {} +#else +BlockFreelist::BlockFreelist() {} +#endif + +BlockFreelist::~BlockFreelist() { +#ifdef DEALLOCATE_BLOCKS + if (_dictionary != NULL) { + if (Verbose && TraceMetadataChunkAllocation) { + _dictionary->print_free_lists(gclog_or_tty); + } + delete _dictionary; + } +#endif +} + +Metablock* BlockFreelist::initialize_free_chunk(Metablock* block, size_t word_size) { +#ifdef DEALLOCATE_BLOCKS +#ifdef ASSERT + assert(word_size = block->word_size(), "Wrong chunk size"); +#endif + Metablock* result = block; + result->setSize(word_size); + result->linkPrev(NULL); + result->linkNext(NULL); + + return result; +#else + ShouldNotReachHere(); + return block; +#endif +} + +void BlockFreelist::return_block(Metablock* block, size_t word_size) { +#ifdef ASSERT + assert(word_size = block->word_size(), "Block size is wrong");; +#endif + Metablock* free_chunk = initialize_free_chunk(block, word_size); +#ifdef DEALLOCATE_BLOCKS + if (dictionary() == NULL) { + _dictionary = new BinaryTreeDictionary(false /* adaptive_freelists */); + } + dictionary()->returnChunk(free_chunk); +#endif +} + +Metablock* BlockFreelist::get_block(size_t word_size) { +#ifdef DEALLOCATE_BLOCKS + if (dictionary() == NULL) { + return NULL; + } + + Metablock* free_chunk = + dictionary()->getChunk(word_size, FreeBlockDictionary::exactly); +#else + Metablock* free_chunk = NULL; +#endif + if (free_chunk == NULL) { + return NULL; + } + assert(free_chunk->word_size() == word_size, "Size of chunk is incorrect"); + Metablock* block = Metablock::initialize((MetaWord*) free_chunk, word_size); +#ifdef ASSERT + assert(block->word_size() == word_size, "Block size is not set correctly"); +#endif + + return block; +} + +void BlockFreelist::print_on(outputStream* st) const { +#ifdef DEALLOCATE_BLOCKS + if (dictionary() == NULL) { + return; + } + dictionary()->print_free_lists(st); +#else + return; +#endif +} + +// VirtualSpaceNode methods + +VirtualSpaceNode::~VirtualSpaceNode() { + _rs.release(); +} + +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)); +} + + +// 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); + + // Point the chunk at the space + Metachunk* result = Metachunk::initialize(chunk_limit, chunk_word_size); + 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 = NULL; + + return take_from_committed(chunk_word_size); +} + +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; + } + + // Commit only 1 page instead of the whole reserved space _rs.size() + size_t committed_byte_size = os::vm_page_size(); + 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, used * 100 / capacity, + bottom(), top(), end(), + vs->high_boundary()); +} + +void VirtualSpaceNode::mangle() { + size_t word_size = capacity_words_in_vs(); + Copy::fill_to_words((HeapWord*) low(), word_size, 0xf1f1f1f1); +} + +// VirtualSpaceList methods +// Space allocated from the VirtualSpace + +VirtualSpaceList::~VirtualSpaceList() { + VirtualSpaceListIterator iter(virtual_space_list()); + while (iter.repeat()) { + VirtualSpaceNode* vsl = iter.get_next(); + delete vsl; + } +} + +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); + + 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(); + assert(succeeded, " VirtualSpaceList initialization should not fail"); + link_vs(class_entry, rs.size()/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 { + 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) { + + // Get a chunk from the chunk freelist + Metachunk* next = chunk_manager()->chunk_freelist_allocate(grow_chunks_by_words); + + // Allocate a chunk out of the current virtual space. + if (next == NULL) { + 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((size_t)SpaceManager::MediumChunkBunch, + 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); + } + if (TraceMetadataHumongousAllocation && SpaceManager::is_humongous(word_size)) { + gclog_or_tty->print_cr(" aligned_expand_vs_by_words " PTR_FORMAT, + aligned_expand_vs_by_words); + gclog_or_tty->print_cr(" grow_vs_words " PTR_FORMAT, + grow_vs_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"); + } + } + + return next; +} + +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); + } + } +} + +#ifndef PRODUCT +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; +} +#endif // PRODUCT + + +// 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 MinHeapFreeRatio and MaxHeapFreeRatio used +// to resize the Java heap by some GC's. New flags can be implemented +// if really needed. MinHeapFreeRatio is used to calculate how much +// free space is desirable in the metaspace capacity to decide how much +// to increase the HWM. MaxHeapFreeRatio 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) { + + // Class virtual space should always be expanded. Call GC for the other + // metadata virtual space. + if (vsl == Metaspace::class_space_list()) return true; + + // If the user wants a limit, impose one. + size_t max_metaspace_size_words = MaxMetaspaceSize / BytesPerWord; + size_t metaspace_size_words = MetaspaceSize / BytesPerWord; + if (!FLAG_IS_DEFAULT(MaxMetaspaceSize) && + vsl->capacity_words_sum() >= max_metaspace_size_words) { + return false; + } + + // 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 (vsl->capacity_words_sum() < metaspace_size_words || + capacity_until_GC() == 0) { + set_capacity_until_GC(metaspace_size_words); + return true; + } else { + if (vsl->capacity_words_sum() < capacity_until_GC()) { + return true; + } else { + if (TraceMetadataChunkAllocation && Verbose) { + gclog_or_tty->print_cr(" allocation request size " SIZE_FORMAT + " capacity_until_GC " SIZE_FORMAT + " capacity_words_sum " SIZE_FORMAT + " used_words_sum " SIZE_FORMAT + " free chunks " SIZE_FORMAT + " free chunks count %d", + word_size, + capacity_until_GC(), + vsl->capacity_words_sum(), + vsl->used_words_sum(), + vsl->chunk_manager()->free_chunks_total(), + vsl->chunk_manager()->free_chunks_count()); + } + return false; + } + } +} + +// Variables are in bytes + +void MetaspaceGC::compute_new_size() { + assert(_shrink_factor <= 100, "invalid shrink factor"); + uint current_shrink_factor = _shrink_factor; + _shrink_factor = 0; + + VirtualSpaceList *vsl = Metaspace::space_list(); + + size_t capacity_after_gc = vsl->capacity_bytes_sum(); + // Check to see if these two can be calculated without walking the CLDG + size_t used_after_gc = vsl->used_bytes_sum(); + size_t capacity_until_GC = vsl->capacity_bytes_sum(); + size_t free_after_gc = capacity_until_GC - used_after_gc; + + const double minimum_free_percentage = MinHeapFreeRatio / 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) { + const double free_percentage = ((double)free_after_gc) / capacity_until_GC; + 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); + double d_free_after_gc = free_after_gc / (double) K; + gclog_or_tty->print_cr(" " + " free_after_gc : %6.1fK" + " used_after_gc : %6.1fK" + " capacity_after_gc : %6.1fK" + " metaspace HWM : %6.1fK", + free_after_gc / (double) K, + used_after_gc / (double) K, + capacity_after_gc / (double) K, + capacity_until_GC / (double) K); + gclog_or_tty->print_cr(" " + " free_percentage: %6.2f", + free_percentage); + } + + + 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) { + size_t expand_words = expand_bytes / BytesPerWord; + MetaspaceGC::inc_capacity_until_GC(expand_words); + } + if (PrintGCDetails && Verbose) { + size_t new_capacity_until_GC = MetaspaceGC::capacity_until_GC_in_bytes(); + gclog_or_tty->print_cr(" expanding:" + " minimum_desired_capacity: %6.1fK" + " expand_words: %6.1fK" + " MinMetaspaceExpansion: %6.1fK" + " new metaspace HWM: %6.1fK", + 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 + size_t shrink_words = 0; + // We would never want to shrink more than this + size_t max_shrink_words = capacity_until_GC - minimum_desired_capacity; + assert(max_shrink_words >= 0, err_msg("max_shrink_words " SIZE_FORMAT, + max_shrink_words)); + + // Should shrinking be considered? + if (MaxHeapFreeRatio < 100) { + const double maximum_free_percentage = MaxHeapFreeRatio / 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 (PrintGC && 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(" " + " capacity_until_GC: %6.1fK" + " minimum_desired_capacity: %6.1fK" + " maximum_desired_capacity: %6.1fK", + capacity_until_GC / (double) K, + 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_words = 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_words = shrink_words / 100 * current_shrink_factor; + assert(shrink_words <= max_shrink_words, + err_msg("invalid shrink size " SIZE_FORMAT " not <= " SIZE_FORMAT, + shrink_words, max_shrink_words)); + 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_words: %.1fK" + " current_shrink_factor: %d" + " new shrink factor: %d" + " MinMetaspaceExpansion: %.1fK", + shrink_words / (double) K, + current_shrink_factor, + _shrink_factor, + MinMetaspaceExpansion / (double) K); + } + } + } + + + // Don't shrink unless it's significant + if (shrink_words >= MinMetaspaceExpansion) { + VirtualSpaceNode* csp = vsl->current_virtual_space(); + size_t available_to_shrink = csp->capacity_words_in_vs() - + csp->used_words_in_vs(); + shrink_words = MIN2(shrink_words, available_to_shrink); + csp->shrink_by(shrink_words); + MetaspaceGC::dec_capacity_until_GC(shrink_words); + if (PrintGCDetails && Verbose) { + size_t new_capacity_until_GC = MetaspaceGC::capacity_until_GC_in_bytes(); + gclog_or_tty->print_cr(" metaspace HWM: %.1fK", new_capacity_until_GC / (double) K); + } + } + assert(vsl->used_bytes_sum() == used_after_gc && + used_after_gc <= vsl->capacity_bytes_sum(), + "sanity check"); + +} + +// 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++) { + Metablock* dummy_block = sm->allocate_work(raw_word_size); + if (dummy_block == 0) { + break; + } +#ifdef ASSERT + assert(dummy_block->word_size() == raw_word_size, "Block size is not set correctly"); +#endif + sm->deallocate(dummy_block->data()); + } + } else { + Metadebug::inc_deallocate_block_a_lot_count(); + } +#endif +} + +void Metadebug::init_allocation_fail_alot_count() { + if (MetadataAllocationFailALot) { + _allocation_fail_alot_count = + 1+(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 + +// ChunkList methods + +size_t ChunkList::sum_list_size() { + size_t result = 0; + Metachunk* cur = head(); + while (cur != NULL) { + result += cur->word_size(); + cur = cur->next(); + } + return result; +} + +size_t ChunkList::sum_list_count() { + size_t result = 0; + Metachunk* cur = head(); + while (cur != NULL) { + result++; + cur = cur->next(); + } + return result; +} + +size_t ChunkList::sum_list_capacity() { + size_t result = 0; + Metachunk* cur = head(); + while (cur != NULL) { + result += cur->capacity_word_size(); + cur = cur->next(); + } + return result; +} + +void ChunkList::add_at_head(Metachunk* head, Metachunk* tail) { + assert_lock_strong(SpaceManager::expand_lock()); + assert(tail->next() == NULL, "Not the tail"); + + if (TraceMetadataChunkAllocation && Verbose) { + tty->print("ChunkList::add_at_head: "); + Metachunk* cur = head; + while (cur != NULL) { + tty->print(PTR_FORMAT " (" SIZE_FORMAT ") ", cur, cur->word_size()); + cur = cur->next(); + } + tty->print_cr(""); + } + + if (tail != NULL) { + tail->set_next(_head); + } + set_head(head); +} + +void ChunkList::add_at_head(Metachunk* list) { + if (list == NULL) { + // Nothing to add + return; + } + assert_lock_strong(SpaceManager::expand_lock()); + Metachunk* head = list; + Metachunk* tail = list; + Metachunk* cur = head->next(); + // Search for the tail since it is not passed. + while (cur != NULL) { + tail = cur; + cur = cur->next(); + } + add_at_head(head, tail); +} + +// 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); + 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 + 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() { +#ifdef ASSERT + if (!UseConcMarkSweepGC) { + MutexLockerEx cl(SpaceManager::expand_lock(), + Mutex::_no_safepoint_check_flag); + locked_verify_free_chunks_total(); + locked_verify_free_chunks_count(); + } +#endif +} + +void ChunkManager::locked_verify() { + locked_verify_free_chunks_total(); + locked_verify_free_chunks_count(); +} + +void ChunkManager::locked_print_free_chunks(outputStream* st) { + assert_lock_strong(SpaceManager::expand_lock()); + st->print_cr("Free chunk total 0x%x count 0x%x", + _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 0x%x count 0x%x", + 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 = SmallIndex; i < NumberOfFreeLists; i = next_chunk_index(i)) { + ChunkList* list = free_chunks(i); + + if (list == NULL) { + continue; + } + + result = result + list->sum_list_capacity(); + } + return result; +} + +size_t ChunkManager::sum_free_chunks_count() { + assert_lock_strong(SpaceManager::expand_lock()); + size_t count = 0; + for (ChunkIndex i = SmallIndex; i < NumberOfFreeLists; i = next_chunk_index(i)) { + ChunkList* list = free_chunks(i); + if (list == NULL) { + continue; + } + count = count + list->sum_list_count(); + } + return count; +} + +ChunkList* ChunkManager::find_free_chunks_list(size_t word_size) { + switch (word_size) { + case SpaceManager::SmallChunk : + return &_free_chunks[0]; + case SpaceManager::MediumChunk : + return &_free_chunks[1]; + default: + assert(word_size > SpaceManager::MediumChunk, "List inconsistency"); + return &_free_chunks[2]; + } +} + +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()); + 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"); + // MutexLockerEx fcl(SpaceManager::expand_lock(), Mutex::_no_safepoint_check_flag); + 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()); + + locked_verify(); + ChunkList* free_list = find_free_chunks_list(word_size); + assert(free_list != NULL, "Sanity check"); + + Metachunk* chunk = free_list->head(); + debug_only(Metachunk* debug_head = chunk;) + + if (chunk == NULL) { + return NULL; + } + + Metachunk* prev_chunk = chunk; + if (chunk->word_size() == word_size) { + // Chunk is being removed from the chunks free list. + dec_free_chunks_total(chunk->capacity_word_size()); + // Remove the chunk as the head of the list. + free_list->set_head(chunk->next()); + chunk->set_next(NULL); + + 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 { + assert(SpaceManager::is_humongous(word_size), + "Should only need to check humongous"); + // This code to find the best fit is just for purposes of + // investigating the loss due to fragmentation on a humongous + // chunk. It will be replace by a binaryTreeDictionary for + // the humongous chunks. + uint count = 0; + Metachunk* best_fit = NULL; + Metachunk* best_fit_prev = NULL; + while (chunk != NULL) { + count++; + if (chunk->word_size() < word_size) { + prev_chunk = chunk; + chunk = chunk->next(); + } else if (chunk->word_size() == word_size) { + break; + } else { + if (best_fit == NULL || + best_fit->word_size() > chunk->word_size()) { + best_fit_prev = prev_chunk; + best_fit = chunk; + } + prev_chunk = chunk; + chunk = chunk->next(); + } + } + if (chunk == NULL) { + prev_chunk = best_fit_prev; + chunk = best_fit; + } + 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 + " found at " SIZE_FORMAT " of " SIZE_FORMAT, + chunk->word_size(), word_size, waste, + count, free_list->sum_list_count()); + } + // Chunk is being removed from the chunks free list. + dec_free_chunks_total(chunk->capacity_word_size()); + // Remove the chunk if it is at the head of the list. + if (chunk == free_list->head()) { + free_list->set_head(chunk->next()); + + if (TraceMetadataHumongousAllocation) { + tty->print_cr("ChunkManager::free_chunks_get: humongous free_list " + PTR_FORMAT " chunk " PTR_FORMAT " size " SIZE_FORMAT + " new head " PTR_FORMAT, + free_list, chunk, chunk->word_size(), + free_list->head()); + } + } else { + // Remove a chunk in the interior of the list + prev_chunk->set_next(chunk->next()); + + if (TraceMetadataHumongousAllocation) { + tty->print_cr("ChunkManager::free_chunks_get: humongous free_list " + PTR_FORMAT " chunk " PTR_FORMAT " size " SIZE_FORMAT + PTR_FORMAT " prev " PTR_FORMAT " next " PTR_FORMAT, + free_list, chunk, chunk->word_size(), + prev_chunk, chunk->next()); + } + } + chunk->set_next(NULL); + } else { + if (TraceMetadataHumongousAllocation) { + tty->print_cr("ChunkManager::free_chunks_get: New humongous chunk of size " + SIZE_FORMAT, + word_size); + } + } + } + locked_verify(); + return chunk; +} + +Metachunk* ChunkManager::chunk_freelist_allocate(size_t word_size) { + assert_lock_strong(SpaceManager::expand_lock()); + 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() || + SpaceManager::is_humongous(chunk->word_size()), + "Non-humongous variable sized chunk"); + if (TraceMetadataChunkAllocation) { + tty->print("ChunkManager::chunk_freelist_allocate: chunk " + PTR_FORMAT " size " SIZE_FORMAT " ", + chunk, chunk->word_size()); + locked_print_free_chunks(tty); + } + + return chunk; +} + +// SpaceManager methods + +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 = SmallIndex; i < NumberOfFreeLists; 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 = SmallIndex; i < NumberOfFreeLists; i = next_chunk_index(i)) { + // Count the free space in all the chunk but not the + // current chunk from which allocations are still being done. + 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; + size_t count = 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) { + while (chunk != NULL) { + if (chunk != current_chunk()) { + result += chunk->free_word_size(); + } + chunk = chunk->next(); + count++; + } + } + return result; +} + +size_t SpaceManager::sum_capacity_in_chunks_in_use() const { + MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag); + size_t sum = 0; + for (ChunkIndex i = SmallIndex; i < NumberOfFreeLists; i = next_chunk_index(i)) { + Metachunk* chunk = chunks_in_use(i); + while (chunk != NULL) { + // Just changed this sum += chunk->capacity_word_size(); + // sum += chunk->word_size() - Metachunk::overhead(); + 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 = SmallIndex; i < NumberOfFreeLists; 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 = SmallIndex; i < NumberOfFreeLists; 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 { + + Metachunk* small_chunk = chunks_in_use(SmallIndex); + st->print_cr("SpaceManager: small chunk " PTR_FORMAT + " free " SIZE_FORMAT, + small_chunk, + small_chunk->free_word_size()); + + Metachunk* medium_chunk = chunks_in_use(MediumIndex); + st->print("medium chunk " PTR_FORMAT, medium_chunk); + Metachunk* tail = current_chunk(); + st->print_cr(" current chunk " PTR_FORMAT, tail); + + Metachunk* head = chunks_in_use(HumongousIndex); + st->print_cr("humongous chunk " PTR_FORMAT, head); + + 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) SpaceManager::SmallChunk; + if (word_size + Metachunk::overhead() > SpaceManager::SmallChunk) { + chunk_word_size = MediumChunk; + } + } else { + chunk_word_size = MediumChunk; + } + + // Might still need a humongous chunk + chunk_word_size = + MAX2((size_t) chunk_word_size, word_size + Metachunk::overhead()); + + 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(" block overhead " PTR_FORMAT + " chunk overhead " PTR_FORMAT, + Metablock::overhead(), + Metachunk::overhead()); + } + return chunk_word_size; +} + +Metablock* 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) { + gclog_or_tty->print_cr("SpaceManager::grow_and_allocate for " SIZE_FORMAT + " words " SIZE_FORMAT " space left", + word_size, current_chunk() != NULL ? + current_chunk()->free_word_size() : 0); + } + + // Get another chunk out of the virtual space + size_t grow_chunks_by_words = calc_chunk_size(word_size); + Metachunk* next = vs_list()->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 = SmallIndex; + i < NumberOfFreeLists ; + 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)); + // Nothing in them yet + // block_freelists()->print_on(st); +} + +SpaceManager::SpaceManager(Mutex* lock, VirtualSpaceList* vs_list) : + _vs_list(vs_list), + _allocation_total(0), + _lock(lock) { + Metadebug::init_allocation_fail_alot_count(); + for (ChunkIndex i = SmallIndex; i < NumberOfFreeLists; 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); + } +} + +SpaceManager::~SpaceManager() { + MutexLockerEx fcl(SpaceManager::expand_lock(), + Mutex::_no_safepoint_check_flag); + + ChunkManager* chunk_manager = vs_list()->chunk_manager(); + + chunk_manager->locked_verify(); + + if (TraceMetadataChunkAllocation && Verbose) { + gclog_or_tty->print_cr("~SpaceManager(): " PTR_FORMAT, this); + locked_print_chunks_in_use_on(gclog_or_tty); + } + + // Have to update before the chunks_in_use lists are emptied + // below. + chunk_manager->inc_free_chunks_total(sum_capacity_in_chunks_in_use(), + sum_count_in_chunks_in_use()); + +#ifdef ASSERT + // Mangle freed memory. + mangle_freed_chunks(); +#endif // ASSERT + + // Add all the chunks in use by this space manager + // to the global list of free chunks. + + // Small chunks. There is one _current_chunk for each + // Metaspace. It could point to a small or medium chunk. + // Rather than determine which it is, follow the list of + // small chunks to add them to the free list + Metachunk* small_chunk = chunks_in_use(SmallIndex); + chunk_manager->free_small_chunks()->add_at_head(small_chunk); + set_chunks_in_use(SmallIndex, NULL); + + // After the small chunk are the medium chunks + Metachunk* medium_chunk = chunks_in_use(MediumIndex); + assert(medium_chunk == NULL || + medium_chunk->word_size() == MediumChunk, + "Chunk is on the wrong list"); + + if (medium_chunk != NULL) { + Metachunk* head = medium_chunk; + // If there is a medium chunk then the _current_chunk can only + // point to the last medium chunk. + Metachunk* tail = current_chunk(); + chunk_manager->free_medium_chunks()->add_at_head(head, tail); + set_chunks_in_use(MediumIndex, NULL); + } + + // Humongous chunks + // Humongous chunks are never the current chunk. + Metachunk* humongous_chunks = chunks_in_use(HumongousIndex); + + if (humongous_chunks != NULL) { + chunk_manager->free_humongous_chunks()->add_at_head(humongous_chunks); + set_chunks_in_use(HumongousIndex, NULL); + } + chunk_manager->locked_verify(); +} + +void SpaceManager::deallocate(MetaWord* p) { + assert_lock_strong(_lock); + ShouldNotReachHere(); // Where is this needed. +#ifdef DEALLOCATE_BLOCKS + Metablock* block = Metablock::metablock_from_data(p); + // This is expense but kept it until integration JJJ + assert(contains((address)block), "Block does not belong to this metaspace"); + block_freelists()->return_block(block, word_size); +#endif +} + +// 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. + switch (new_chunk->word_size()) { + case SpaceManager::SmallChunk : + if (chunks_in_use(SmallIndex) == NULL) { + // First chunk to add to the list + set_chunks_in_use(SmallIndex, new_chunk); + } else { + assert(current_chunk()->word_size() == SpaceManager::SmallChunk, + err_msg( "Incorrect mix of sizes in chunk list " + SIZE_FORMAT " new chunk " SIZE_FORMAT, + current_chunk()->word_size(), new_chunk->word_size())); + current_chunk()->set_next(new_chunk); + } + // Make current chunk + set_current_chunk(new_chunk); + break; + case SpaceManager::MediumChunk : + if (chunks_in_use(MediumIndex) == NULL) { + // About to add the first medium chunk so teminate the + // small chunk list. In general once medium chunks are + // being added, we're past the need for small chunks. + if (current_chunk() != NULL) { + // Only a small chunk or the initial chunk could be + // the current chunk if this is the first medium chunk. + assert(current_chunk()->word_size() == SpaceManager::SmallChunk || + chunks_in_use(SmallIndex) == NULL, + err_msg("Should be a small chunk or initial chunk, current chunk " + SIZE_FORMAT " new chunk " SIZE_FORMAT, + current_chunk()->word_size(), new_chunk->word_size())); + current_chunk()->set_next(NULL); + } + // First chunk to add to the list + set_chunks_in_use(MediumIndex, new_chunk); + + } else { + // As a minimum the first medium chunk added would + // have become the _current_chunk + // so the _current_chunk has to be non-NULL here + // (although not necessarily still the first medium chunk). + assert(current_chunk()->word_size() == SpaceManager::MediumChunk, + "A medium chunk should the current chunk"); + current_chunk()->set_next(new_chunk); + } + // Make current chunk + set_current_chunk(new_chunk); + break; + default: { + // 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() > MediumChunk, "List inconsistency"); + } + } + + 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); + vs_list()->chunk_manager()->locked_print_free_chunks(tty); + } +} + +MetaWord* SpaceManager::allocate(size_t word_size) { + MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag); + + size_t block_overhead = Metablock::overhead(); + // 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_with_overhead = (word_size + block_overhead) * BytesPerWord; +#ifdef DEALLOCATE_BLOCKS + size_t raw_bytes_size = MAX2(ARENA_ALIGN(byte_size_with_overhead), + MinChunkSize * BytesPerWord); +#else + size_t raw_bytes_size = ARENA_ALIGN(byte_size_with_overhead); +#endif + size_t raw_word_size = raw_bytes_size / BytesPerWord; + assert(raw_word_size * BytesPerWord == raw_bytes_size, "Size problem"); + + BlockFreelist* fl = block_freelists(); + Metablock* block = 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->totalSize() > allocation_from_dictionary_limit) { + block = fl->get_block(raw_word_size); + } + if (block == NULL) { + block = allocate_work(raw_word_size); + if (block == NULL) { + return NULL; + } + } + Metadebug::deallocate_block_a_lot(this, raw_word_size); + + // Push the allocation past the word containing the size and leader. +#ifdef ASSERT + MetaWord* result = block->data(); + return result; +#else + return (MetaWord*) block; +#endif +} + +// Returns the address of spaced allocated for "word_size". +// This methods does not know about blocks (Metablocks) +Metablock* 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? + Metablock* 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_allocation_total(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_allocation_total(word_size); + assert(result != (Metablock*) chunks_in_use(MediumIndex), "Head of the list is being allocated"); + assert(result->word_size() == word_size, "Size not set correctly"); + } + + 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()->totalSize() == 0) { + // Skip the small chunks because their next link points to + // medium chunks. This is because the small chunk is the + // current chunk (for allocations) until it is full and the + // the addition of the next chunk does not NULL the next + // like of the small chunk. + for (ChunkIndex i = MediumIndex; i < NumberOfFreeLists; i = next_chunk_index(i)) { + Metachunk* curr = chunks_in_use(i); + while (curr != NULL) { + curr->verify(); + curr = curr->next(); + } + } + } +} + +#ifdef ASSERT +void SpaceManager::verify_allocation_total() { +#if 0 + // Verification is only guaranteed at a safepoint. + if (SafepointSynchronize::is_at_safepoint()) { + gclog_or_tty->print_cr("Chunk " PTR_FORMAT " allocation_total " SIZE_FORMAT + " sum_used_in_chunks_in_use " SIZE_FORMAT, + this, + allocation_total(), + sum_used_in_chunks_in_use()); + } + MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag); + assert(allocation_total() == sum_used_in_chunks_in_use(), + err_msg("allocation total is not consistent %d vs %d", + allocation_total(), sum_used_in_chunks_in_use())); +#endif +} + +#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 = SmallIndex; + index < NumberOfFreeLists; + 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()->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 = SmallIndex; + index < NumberOfFreeLists; + index = next_chunk_index(index)) { + for (Metachunk* curr = chunks_in_use(index); + curr != NULL; + curr = curr->next()) { + // Try to detect incorrectly terminated small chunk + // list. + assert(index == MediumIndex || curr != chunks_in_use(MediumIndex), + err_msg("Mangling medium chunks in small chunks? " + "curr " PTR_FORMAT " medium list " PTR_FORMAT, + curr, chunks_in_use(MediumIndex))); + curr->mangle(); + } + } +} +#endif // PRODUCT + + +// MetaspaceAux + +size_t MetaspaceAux::used_in_bytes(Metaspace::MetadataType mdtype) { + size_t used = 0; +#ifdef ASSERT + size_t free = 0; + size_t capacity = 0; +#endif + ClassLoaderDataGraphMetaspaceIterator iter; + while (iter.repeat()) { + Metaspace* msp = iter.get_next(); + // Sum allocation_total for each metaspace + if (msp != NULL) { + used += msp->used_words(mdtype); +#ifdef ASSERT + free += msp->free_words(mdtype); + capacity += msp->capacity_words(mdtype); + assert(used + free == capacity, + err_msg("Accounting is wrong used " SIZE_FORMAT + " free " SIZE_FORMAT " capacity " SIZE_FORMAT, + used, free, capacity)); +#endif + } + } + 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; +} + +// The total words available for metadata allocation. This +// uses Metaspace capacity_words() which is the total words +// in chunks allocated for a Metaspace. +size_t MetaspaceAux::capacity_in_bytes(Metaspace::MetadataType mdtype) { + size_t capacity = free_chunks_total(mdtype); + ClassLoaderDataGraphMetaspaceIterator iter; + while (iter.repeat()) { + Metaspace* msp = iter.get_next(); + if (msp != NULL) { + capacity += msp->capacity_words(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 SpaceManager::MediumChunk; } + +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->verify_free_chunks_total(); + return chunk->free_chunks_total(); +} + +size_t MetaspaceAux::free_chunks_total_in_bytes(Metaspace::MetadataType mdtype) { + return free_chunks_total(mdtype) * 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 "/" SIZE_FORMAT ")", + prev_metadata_used, + used_in_bytes(), + capacity_in_bytes(), + reserved_in_bytes()); + } else { + gclog_or_tty->print(" " SIZE_FORMAT "K" + "->" SIZE_FORMAT "K" + "(" SIZE_FORMAT "K/" SIZE_FORMAT "K)", + prev_metadata_used / K, + used_in_bytes()/ K, + capacity_in_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", + capacity_in_bytes()/K, used_in_bytes()/K, reserved_in_bytes()/K); + out->print_cr(" data space " + SIZE_FORMAT "K, used " SIZE_FORMAT "K," + " reserved " SIZE_FORMAT "K", + capacity_in_bytes(nct)/K, used_in_bytes(nct)/K, reserved_in_bytes(nct)/K); + out->print_cr(" class space " + SIZE_FORMAT "K, used " SIZE_FORMAT "K," + " reserved " SIZE_FORMAT "K", + capacity_in_bytes(ct)/K, used_in_bytes(ct)/K, reserved_in_bytes(ct)/K); +} + +// 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_in_bytes(mdtype); + size_t used_bytes = used_in_bytes(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); + assert(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 small_waste = 0, medium_waste = 0, large_waste = 0; + size_t cls_small_waste = 0, cls_medium_waste = 0, cls_large_waste = 0; + + ClassLoaderDataGraphMetaspaceIterator iter; + while (iter.repeat()) { + Metaspace* msp = iter.get_next(); + if (msp != NULL) { + small_waste += msp->vsm()->sum_waste_in_chunks_in_use(SmallIndex); + medium_waste += msp->vsm()->sum_waste_in_chunks_in_use(MediumIndex); + large_waste += msp->vsm()->sum_waste_in_chunks_in_use(HumongousIndex); + + cls_small_waste += msp->class_vsm()->sum_waste_in_chunks_in_use(SmallIndex); + cls_medium_waste += msp->class_vsm()->sum_waste_in_chunks_in_use(MediumIndex); + cls_large_waste += msp->class_vsm()->sum_waste_in_chunks_in_use(HumongousIndex); + } + } + out->print_cr("Total fragmentation waste (words) doesn't count free space"); + out->print(" data: small " SIZE_FORMAT " medium " SIZE_FORMAT, + small_waste, medium_waste); + out->print_cr(" class: small " SIZE_FORMAT, 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); +} + +// Metaspace methods + +size_t Metaspace::_first_chunk_word_size = 0; + +Metaspace::Metaspace(Mutex* lock, size_t word_size) { + initialize(lock, word_size); +} + +Metaspace::Metaspace(Mutex* lock) { + initialize(lock); +} + +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 this before initializing the VirtualSpaceList + _first_chunk_word_size = InitialBootClassLoaderMetaspaceSize / BytesPerWord; + // Arbitrarily set the initial virtual space to a multiple + // of the boot class loader size. + size_t word_size = VIRTUALSPACEMULTIPLIER * Metaspace::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("%d != %d", rs.size(), ClassMetaspaceSize)); + _class_space_list = new VirtualSpaceList(rs); +} + +// Class space probably needs a lot less than data space +const int class_space_divisor = 4; + +void Metaspace::initialize(Mutex* lock, size_t initial_size) { + // Use SmallChunk size if not specified, adjust class to smaller size if so. + size_t word_size; + size_t class_word_size; + if (initial_size == 0) { + word_size = (size_t) SpaceManager::SmallChunk; + class_word_size = word_size; + } else { + word_size = initial_size; + class_word_size = initial_size/class_space_divisor; + } + + assert(space_list() != NULL, + "Metadata VirtualSpaceList has not been initialized"); + + _vsm = new SpaceManager(lock, space_list()); + if (_vsm == NULL) { + return; + } + + 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()->current_virtual_space()->get_chunk_vs_with_expand(word_size); + 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()->current_virtual_space()->get_chunk_vs_with_expand(class_word_size); + if (class_chunk != NULL) { + class_vsm()->add_chunk(class_chunk, true); + } +} + + +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); + } +} + +// 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(MetadataType mdtype) const { + // return vsm()->allocation_total(); + 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(MetadataType mdtype) const { + return mdtype == ClassType ? class_vsm()->sum_capacity_in_chunks_in_use() : + vsm()->sum_capacity_in_chunks_in_use(); +} + +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 lock +#ifdef DEALLOCATE_BLOCKS + if (is_class) { + class_vsm()->deallocate(ptr); + } else { + vsm()->deallocate(ptr); + } +#else +#ifdef ASSERT + Copy::fill_to_words((HeapWord*)ptr, word_size, metadata_deallocate); +#endif +#endif + + } else { + MutexLocker ml(vsm()->lock()); + +#ifdef DEALLOCATE_BLOCKS + if (is_class) { + class_vsm()->deallocate(ptr); + } else { + vsm()->deallocate(ptr); + } +#else +#ifdef ASSERT + Copy::fill_to_words((HeapWord*)ptr, word_size, metadata_deallocate); +#endif +#endif + } +} + +MetaWord* 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 result; + } + + 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) { + // -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 result; +} + +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); + } +} + +#ifndef PRODUCT +bool Metaspace::contains(const void * ptr) const { + if (MetaspaceShared::is_in_shared_space(ptr)) { + return true; + } + MutexLockerEx cl(SpaceManager::expand_lock(), Mutex::_no_safepoint_check_flag); + return space_list()->contains(ptr) || class_space_list()->contains(ptr); +} +#endif + +void Metaspace::verify() { + vsm()->verify(); + class_vsm()->verify(); +} + +void Metaspace::dump(outputStream* const out) const { + if (UseMallocOnly) { + // Just print usage for now + out->print_cr("usage %d", used_words(Metaspace::NonClassType)); + } + 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); +}