1 /* 2 * Copyright (c) 2018, 2019, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. 8 * 9 * This code is distributed in the hope that it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 12 * version 2 for more details (a copy is included in the LICENSE file that 13 * accompanied this code). 14 * 15 * You should have received a copy of the GNU General Public License version 16 * 2 along with this work; if not, write to the Free Software Foundation, 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 18 * 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 20 * or visit www.oracle.com if you need additional information or have any 21 * questions. 22 * 23 */ 24 25 #ifndef SHARE_MEMORY_METASPACE_SPACEMANAGER_HPP 26 #define SHARE_MEMORY_METASPACE_SPACEMANAGER_HPP 27 28 #include "memory/allocation.hpp" 29 #include "memory/metaspace.hpp" 30 #include "memory/metaspace/blockFreelist.hpp" 31 #include "memory/metaspace/metaspaceCommon.hpp" 32 #include "memory/metaspace/metachunk.hpp" 33 #include "memory/metaspace/metaspaceStatistics.hpp" 34 #include "utilities/debug.hpp" 35 #include "utilities/globalDefinitions.hpp" 36 37 class outputStream; 38 class Mutex; 39 40 namespace metaspace { 41 42 // SpaceManager - used by Metaspace to handle allocations 43 class SpaceManager : public CHeapObj<mtClass> { 44 friend class ::ClassLoaderMetaspace; 45 friend class Metadebug; 46 47 private: 48 49 // protects allocations 50 Mutex* const _lock; 51 52 // Type of metadata allocated. 53 const Metaspace::MetadataType _mdtype; 54 55 // Type of metaspace 56 const Metaspace::MetaspaceType _space_type; 57 58 // List of chunks in use by this SpaceManager. Allocations 59 // are done from the current chunk. The list is used for deallocating 60 // chunks when the SpaceManager is freed. 61 Metachunk* _chunk_list; 62 Metachunk* _current_chunk; 63 64 enum { 65 66 // Maximum number of small chunks to allocate to a SpaceManager 67 small_chunk_limit = 4, 68 69 // Maximum number of specialize chunks to allocate for anonymous and delegating 70 // metadata space to a SpaceManager 71 anon_and_delegating_metadata_specialize_chunk_limit = 4, 72 73 allocation_from_dictionary_limit = 4 * K 74 75 }; 76 77 // Some running counters, but lets keep their number small to not add to much to 78 // the per-classloader footprint. 79 // Note: capacity = used + free + waste + overhead. We do not keep running counters for 80 // free and waste. Their sum can be deduced from the three other values. 81 size_t _overhead_words; 82 size_t _capacity_words; 83 size_t _used_words; 84 uintx _num_chunks_by_type[NumberOfInUseLists]; 85 86 // Free lists of blocks are per SpaceManager since they 87 // are assumed to be in chunks in use by the SpaceManager 88 // and all chunks in use by a SpaceManager are freed when 89 // the class loader using the SpaceManager is collected. 90 BlockFreelist* _block_freelists; 91 92 private: 93 // Accessors 94 Metachunk* chunk_list() const { return _chunk_list; } 95 96 BlockFreelist* block_freelists() const { return _block_freelists; } 97 98 Metaspace::MetadataType mdtype() { return _mdtype; } 99 100 VirtualSpaceList* vs_list() const { return Metaspace::get_space_list(_mdtype); } 101 ChunkManager* chunk_manager() const { return Metaspace::get_chunk_manager(_mdtype); } 102 103 Metachunk* current_chunk() const { return _current_chunk; } 104 void set_current_chunk(Metachunk* v) { 105 _current_chunk = v; 106 } 107 108 Metachunk* find_current_chunk(size_t word_size); 109 110 // Add chunk to the list of chunks in use 111 void add_chunk(Metachunk* v, bool make_current); 112 void retire_current_chunk(); 113 114 Mutex* lock() const { return _lock; } 115 116 // Adds to the given statistic object. Expects to be locked with lock(). 117 void add_to_statistics_locked(SpaceManagerStatistics* out) const; 118 119 // Verify internal counters against the current state. Expects to be locked with lock(). 120 DEBUG_ONLY(void verify_metrics_locked() const;) 121 122 public: 123 SpaceManager(Metaspace::MetadataType mdtype, 124 Metaspace::MetaspaceType space_type, 125 Mutex* lock); 126 ~SpaceManager(); 127 128 enum ChunkMultiples { 129 MediumChunkMultiple = 4 130 }; 131 132 static size_t specialized_chunk_size(bool is_class) { return is_class ? ClassSpecializedChunk : SpecializedChunk; } 133 static size_t small_chunk_size(bool is_class) { return is_class ? ClassSmallChunk : SmallChunk; } 134 static size_t medium_chunk_size(bool is_class) { return is_class ? ClassMediumChunk : MediumChunk; } 135 136 static size_t smallest_chunk_size(bool is_class) { return specialized_chunk_size(is_class); } 137 138 // Accessors 139 bool is_class() const { return _mdtype == Metaspace::ClassType; } 140 141 size_t specialized_chunk_size() const { return specialized_chunk_size(is_class()); } 142 size_t small_chunk_size() const { return small_chunk_size(is_class()); } 143 size_t medium_chunk_size() const { return medium_chunk_size(is_class()); } 144 145 size_t smallest_chunk_size() const { return smallest_chunk_size(is_class()); } 146 147 size_t medium_chunk_bunch() const { return medium_chunk_size() * MediumChunkMultiple; } 148 149 bool is_humongous(size_t word_size) { return word_size > medium_chunk_size(); } 150 151 size_t capacity_words() const { return _capacity_words; } 152 size_t used_words() const { return _used_words; } 153 size_t overhead_words() const { return _overhead_words; } 154 155 // Adjust local, global counters after a new chunk has been added. 156 void account_for_new_chunk(const Metachunk* new_chunk); 157 158 // Adjust local, global counters after space has been allocated from the current chunk. 159 void account_for_allocation(size_t words); 160 161 // Adjust global counters just before the SpaceManager dies, after all its chunks 162 // have been returned to the freelist. 163 void account_for_spacemanager_death(); 164 165 // Adjust the initial chunk size to match one of the fixed chunk list sizes, 166 // or return the unadjusted size if the requested size is humongous. 167 static size_t adjust_initial_chunk_size(size_t requested, bool is_class_space); 168 size_t adjust_initial_chunk_size(size_t requested) const; 169 170 // Get the initial chunks size for this metaspace type. 171 size_t get_initial_chunk_size(Metaspace::MetaspaceType type) const; 172 173 // Todo: remove this once we have counters by chunk type. 174 uintx num_chunks_by_type(ChunkIndex chunk_type) const { return _num_chunks_by_type[chunk_type]; } 175 176 Metachunk* get_new_chunk(size_t chunk_word_size); 177 178 // Block allocation and deallocation. 179 // Allocates a block from the current chunk 180 MetaWord* allocate(size_t word_size); 181 182 // Helper for allocations 183 MetaWord* allocate_work(size_t word_size); 184 185 // Returns a block to the per manager freelist 186 void deallocate(MetaWord* p, size_t word_size); 187 188 // Based on the allocation size and a minimum chunk size, 189 // returned chunk size (for expanding space for chunk allocation). 190 size_t calc_chunk_size(size_t allocation_word_size); 191 192 // Called when an allocation from the current chunk fails. 193 // Gets a new chunk (may require getting a new virtual space), 194 // and allocates from that chunk. 195 MetaWord* grow_and_allocate(size_t word_size); 196 197 // Notify memory usage to MemoryService. 198 void track_metaspace_memory_usage(); 199 200 // debugging support. 201 202 void print_on(outputStream* st) const; 203 void locked_print_chunks_in_use_on(outputStream* st) const; 204 205 void verify(); 206 void verify_chunk_size(Metachunk* chunk); 207 208 // This adjusts the size given to be greater than the minimum allocation size in 209 // words for data in metaspace. Esentially the minimum size is currently 3 words. 210 size_t get_allocation_word_size(size_t word_size) { 211 size_t byte_size = word_size * BytesPerWord; 212 213 size_t raw_bytes_size = MAX2(byte_size, sizeof(Metablock)); 214 raw_bytes_size = align_up(raw_bytes_size, Metachunk::object_alignment()); 215 216 size_t raw_word_size = raw_bytes_size / BytesPerWord; 217 assert(raw_word_size * BytesPerWord == raw_bytes_size, "Size problem"); 218 219 return raw_word_size; 220 } 221 222 // Adds to the given statistic object. 223 void add_to_statistics(SpaceManagerStatistics* out) const; 224 225 // Verify internal counters against the current state. 226 DEBUG_ONLY(void verify_metrics() const;) 227 228 }; 229 230 231 } // namespace metaspace 232 233 #endif // SHARE_MEMORY_METASPACE_SPACEMANAGER_HPP