coleenp@4037: /*
coleenp@4037:  * Copyright (c) 2011, 2012, Oracle and/or its affiliates. All rights reserved.
coleenp@4037:  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
coleenp@4037:  *
coleenp@4037:  * This code is free software; you can redistribute it and/or modify it
coleenp@4037:  * under the terms of the GNU General Public License version 2 only, as
coleenp@4037:  * published by the Free Software Foundation.
coleenp@4037:  *
coleenp@4037:  * This code is distributed in the hope that it will be useful, but WITHOUT
coleenp@4037:  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
coleenp@4037:  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
coleenp@4037:  * version 2 for more details (a copy is included in the LICENSE file that
coleenp@4037:  * accompanied this code).
coleenp@4037:  *
coleenp@4037:  * You should have received a copy of the GNU General Public License version
coleenp@4037:  * 2 along with this work; if not, write to the Free Software Foundation,
coleenp@4037:  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
coleenp@4037:  *
coleenp@4037:  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
coleenp@4037:  * or visit www.oracle.com if you need additional information or have any
coleenp@4037:  * questions.
coleenp@4037:  *
coleenp@4037:  */
coleenp@4037: #ifndef SHARE_VM_MEMORY_METASPACE_HPP
coleenp@4037: #define SHARE_VM_MEMORY_METASPACE_HPP
coleenp@4037: 
coleenp@4037: #include "memory/allocation.hpp"
coleenp@4037: #include "memory/memRegion.hpp"
coleenp@4037: #include "runtime/virtualspace.hpp"
coleenp@4037: #include "utilities/exceptions.hpp"
coleenp@4037: 
coleenp@4037: // Metaspace
coleenp@4037: //
coleenp@4037: // Metaspaces are Arenas for the VM's metadata.
coleenp@4037: // They are allocated one per class loader object, and one for the null
coleenp@4037: // bootstrap class loader
coleenp@4037: // Eventually for bootstrap loader we'll have a read-only section and read-write
coleenp@4037: // to write for DumpSharedSpaces and read for UseSharedSpaces
coleenp@4037: //
coleenp@4037: //    block X ---+       +-------------------+
coleenp@4037: //               |       |  Virtualspace     |
coleenp@4037: //               |       |                   |
coleenp@4037: //               |       |                   |
coleenp@4037: //               |       |-------------------|
coleenp@4037: //               |       || Chunk            |
coleenp@4037: //               |       ||                  |
coleenp@4037: //               |       ||----------        |
coleenp@4037: //               +------>||| block 0 |       |
coleenp@4037: //                       ||----------        |
coleenp@4037: //                       ||| block 1 |       |
coleenp@4037: //                       ||----------        |
coleenp@4037: //                       ||                  |
coleenp@4037: //                       |-------------------|
coleenp@4037: //                       |                   |
coleenp@4037: //                       |                   |
coleenp@4037: //                       +-------------------+
coleenp@4037: //
coleenp@4037: 
coleenp@4037: class ClassLoaderData;
coleenp@4037: class MetaWord;
coleenp@4037: class Mutex;
coleenp@4037: class outputStream;
coleenp@4037: class FreeChunk;
coleenp@4037: template <class Chunk_t> class FreeList;
coleenp@4037: template <class Chunk_t> class BinaryTreeDictionary;
coleenp@4037: class SpaceManager;
coleenp@4037: 
coleenp@4037: // Metaspaces each have a  SpaceManager and allocations
coleenp@4037: // are done by the SpaceManager.  Allocations are done
coleenp@4037: // out of the current Metachunk.  When the current Metachunk
coleenp@4037: // is exhausted, the SpaceManager gets a new one from
coleenp@4037: // the current VirtualSpace.  When the VirtualSpace is exhausted
coleenp@4037: // the SpaceManager gets a new one.  The SpaceManager
coleenp@4037: // also manages freelists of available Chunks.
coleenp@4037: //
coleenp@4037: // Currently the space manager maintains the list of
coleenp@4037: // virtual spaces and the list of chunks in use.  Its
coleenp@4037: // allocate() method returns a block for use as a
coleenp@4037: // quantum of metadata.
coleenp@4037: 
coleenp@4037: class VirtualSpaceList;
coleenp@4037: 
coleenp@4037: class Metaspace : public CHeapObj<mtClass> {
coleenp@4037:   friend class VMStructs;
coleenp@4037:   friend class SpaceManager;
coleenp@4037:   friend class VM_CollectForMetadataAllocation;
coleenp@4037:   friend class MetaspaceGC;
coleenp@4037:   friend class MetaspaceAux;
coleenp@4037: 
coleenp@4037:  public:
coleenp@4037:   enum MetadataType {ClassType, NonClassType};
coleenp@4037: 
coleenp@4037:  private:
coleenp@4037:   void initialize(Mutex* lock, size_t initial_size = 0);
coleenp@4037: 
coleenp@4037:   static size_t _first_chunk_word_size;
coleenp@4037: 
coleenp@4037:   SpaceManager* _vsm;
coleenp@4037:   SpaceManager* vsm() const { return _vsm; }
coleenp@4037: 
coleenp@4037:   SpaceManager* _class_vsm;
coleenp@4037:   SpaceManager* class_vsm() const { return _class_vsm; }
coleenp@4037: 
coleenp@4037:   MetaWord* allocate(size_t word_size, MetadataType mdtype);
coleenp@4037: 
coleenp@4037:   // Virtual Space lists for both classes and other metadata
coleenp@4037:   static VirtualSpaceList* _space_list;
coleenp@4037:   static VirtualSpaceList* _class_space_list;
coleenp@4037: 
coleenp@4037:   static VirtualSpaceList* space_list()       { return _space_list; }
coleenp@4037:   static VirtualSpaceList* class_space_list() { return _class_space_list; }
coleenp@4037: 
coleenp@4037:  public:
coleenp@4037: 
coleenp@4037:   Metaspace(Mutex* lock, size_t initial_size);
coleenp@4037:   Metaspace(Mutex* lock);
coleenp@4037:   ~Metaspace();
coleenp@4037: 
coleenp@4037:   // Initialize globals for Metaspace
coleenp@4037:   static void global_initialize();
coleenp@4037:   static void initialize_class_space(ReservedSpace rs);
coleenp@4037: 
coleenp@4037:   static size_t first_chunk_word_size() { return _first_chunk_word_size; }
coleenp@4037: 
coleenp@4037:   char*  bottom() const;
coleenp@4037:   size_t used_words(MetadataType mdtype) const;
coleenp@4037:   size_t free_words(MetadataType mdtype) const;
coleenp@4037:   size_t capacity_words(MetadataType mdtype) const;
coleenp@4037:   size_t waste_words(MetadataType mdtype) const;
coleenp@4037: 
coleenp@4037:   static MetaWord* allocate(ClassLoaderData* loader_data, size_t size,
coleenp@4037:                             bool read_only, MetadataType mdtype, TRAPS);
jmasa@4064:   void deallocate(MetaWord* ptr, size_t byte_size, bool is_class);
coleenp@4037: 
jmasa@4064:   MetaWord* expand_and_allocate(size_t size,
jmasa@4064:                                 MetadataType mdtype);
coleenp@4037: 
coleenp@4037: #ifndef PRODUCT
coleenp@4037:   bool contains(const void *ptr) const;
coleenp@4037:   bool contains_class(const void *ptr) const;
coleenp@4037: #endif
coleenp@4037: 
coleenp@4037:   void dump(outputStream* const out) const;
coleenp@4037: 
coleenp@4037:   void print_on(outputStream* st) const;
coleenp@4037:   // Debugging support
coleenp@4037:   void verify();
coleenp@4037: };
coleenp@4037: 
coleenp@4037: class MetaspaceAux : AllStatic {
coleenp@4037: 
coleenp@4037:   // Statistics for class space and data space in metaspace.
coleenp@4037:   static size_t used_in_bytes(Metaspace::MetadataType mdtype);
coleenp@4037:   static size_t free_in_bytes(Metaspace::MetadataType mdtype);
coleenp@4037:   static size_t capacity_in_bytes(Metaspace::MetadataType mdtype);
coleenp@4037:   static size_t reserved_in_bytes(Metaspace::MetadataType mdtype);
coleenp@4037: 
coleenp@4037:   static size_t free_chunks_total(Metaspace::MetadataType mdtype);
coleenp@4037:   static size_t free_chunks_total_in_bytes(Metaspace::MetadataType mdtype);
coleenp@4037: 
coleenp@4037:  public:
coleenp@4037:   // Total of space allocated to metadata in all Metaspaces
coleenp@4037:   static size_t used_in_bytes() {
coleenp@4037:     return used_in_bytes(Metaspace::ClassType) +
coleenp@4037:            used_in_bytes(Metaspace::NonClassType);
coleenp@4037:   }
coleenp@4037: 
coleenp@4037:   // Total of available space in all Metaspaces
coleenp@4037:   // Total of capacity allocated to all Metaspaces.  This includes
coleenp@4037:   // space in Metachunks not yet allocated and in the Metachunk
coleenp@4037:   // freelist.
coleenp@4037:   static size_t capacity_in_bytes() {
coleenp@4037:     return capacity_in_bytes(Metaspace::ClassType) +
coleenp@4037:            capacity_in_bytes(Metaspace::NonClassType);
coleenp@4037:   }
coleenp@4037: 
coleenp@4037:   // Total space reserved in all Metaspaces
coleenp@4037:   static size_t reserved_in_bytes() {
coleenp@4037:     return reserved_in_bytes(Metaspace::ClassType) +
coleenp@4037:            reserved_in_bytes(Metaspace::NonClassType);
coleenp@4037:   }
coleenp@4037: 
coleenp@4037:   static size_t min_chunk_size();
coleenp@4037: 
coleenp@4037:   // Print change in used metadata.
coleenp@4037:   static void print_metaspace_change(size_t prev_metadata_used);
coleenp@4037:   static void print_on(outputStream * out);
coleenp@4037:   static void print_on(outputStream * out, Metaspace::MetadataType mdtype);
coleenp@4037: 
coleenp@4037:   static void print_waste(outputStream* out);
coleenp@4037:   static void dump(outputStream* out);
coleenp@4037: };
coleenp@4037: 
coleenp@4037: // Metaspace are deallocated when their class loader are GC'ed.
coleenp@4037: // This class implements a policy for inducing GC's to recover
coleenp@4037: // Metaspaces.
coleenp@4037: 
coleenp@4037: class MetaspaceGC : AllStatic {
coleenp@4037: 
coleenp@4037:   // The current high-water-mark for inducing a GC.  When
coleenp@4037:   // the capacity of all space in the virtual lists reaches this value,
coleenp@4037:   // a GC is induced and the value is increased.  This should be changed
coleenp@4037:   // to the space actually used for allocations to avoid affects of
coleenp@4037:   // fragmentation losses to partially used chunks.  Size is in words.
coleenp@4037:   static size_t _capacity_until_GC;
coleenp@4037: 
coleenp@4037:   // After a GC is done any allocation that fails should try to expand
coleenp@4037:   // the capacity of the Metaspaces.  This flag is set during attempts
coleenp@4037:   // to allocate in the VMGCOperation that does the GC.
coleenp@4037:   static bool _expand_after_GC;
coleenp@4037: 
coleenp@4037:   // For a CMS collection, signal that a concurrent collection should
coleenp@4037:   // be started.
coleenp@4037:   static bool _should_concurrent_collect;
coleenp@4037: 
coleenp@4037:   static uint _shrink_factor;
coleenp@4037: 
coleenp@4037:   static void set_capacity_until_GC(size_t v) { _capacity_until_GC = v; }
coleenp@4037: 
coleenp@4037:   static size_t shrink_factor() { return _shrink_factor; }
coleenp@4037:   void set_shrink_factor(uint v) { _shrink_factor = v; }
coleenp@4037: 
coleenp@4037:  public:
coleenp@4037: 
coleenp@4037:   static size_t capacity_until_GC() { return _capacity_until_GC; }
coleenp@4037:   static size_t capacity_until_GC_in_bytes() { return _capacity_until_GC * BytesPerWord; }
coleenp@4037:   static void inc_capacity_until_GC(size_t v) { _capacity_until_GC += v; }
coleenp@4037:   static void dec_capacity_until_GC(size_t v) {
coleenp@4037:     _capacity_until_GC = _capacity_until_GC > v ? _capacity_until_GC - v : 0;
coleenp@4037:   }
coleenp@4037:   static bool expand_after_GC()           { return _expand_after_GC; }
coleenp@4037:   static void set_expand_after_GC(bool v) { _expand_after_GC = v; }
coleenp@4037: 
coleenp@4037:   static bool should_concurrent_collect() { return _should_concurrent_collect; }
coleenp@4037:   static void set_should_concurrent_collect(bool v) {
coleenp@4037:     _should_concurrent_collect = v;
coleenp@4037:   }
coleenp@4037: 
coleenp@4037:   // The amount to increase the high-water-mark (_capacity_until_GC)
coleenp@4037:   static size_t delta_capacity_until_GC(size_t word_size);
coleenp@4037: 
coleenp@4037:   // It is expected that this will be called when the current capacity
coleenp@4037:   // has been used and a GC should be considered.
coleenp@4037:   static bool should_expand(VirtualSpaceList* vsl, size_t word_size);
coleenp@4037: 
coleenp@4037:   // Calculate the new high-water mark at which to induce
coleenp@4037:   // a GC.
coleenp@4037:   static void compute_new_size();
coleenp@4037: };
coleenp@4037: 
coleenp@4037: #endif // SHARE_VM_MEMORY_METASPACE_HPP