1 /* 2 * Copyright (c) 2018, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. 8 * 9 * This code is distributed in the hope that it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 12 * version 2 for more details (a copy is included in the LICENSE file that 13 * accompanied this code). 14 * 15 * You should have received a copy of the GNU General Public License version 16 * 2 along with this work; if not, write to the Free Software Foundation, 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 18 * 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 20 * or visit www.oracle.com if you need additional information or have any 21 * questions. 22 * 23 */ 24 #include "precompiled.hpp" 25 26 #include "logging/log.hpp" 27 #include "memory/binaryTreeDictionary.inline.hpp" 28 #include "memory/metaspace/blockFreelist.hpp" 29 #include "utilities/ostream.hpp" 30 #include "utilities/globalDefinitions.hpp" 31 32 33 namespace metaspace { 34 namespace internals { 35 36 37 BlockFreelist::BlockFreelist() : _dictionary(new BlockTreeDictionary()), _small_blocks(NULL) {} 38 39 BlockFreelist::~BlockFreelist() { 40 delete _dictionary; 41 if (_small_blocks != NULL) { 42 delete _small_blocks; 43 } 44 } 45 46 void BlockFreelist::return_block(MetaWord* p, size_t word_size) { 47 assert(word_size >= SmallBlocks::small_block_min_size(), "never return dark matter"); 48 49 Metablock* free_chunk = ::new (p) Metablock(word_size); 50 if (word_size < SmallBlocks::small_block_max_size()) { 51 small_blocks()->return_block(free_chunk, word_size); 52 } else { 53 dictionary()->return_chunk(free_chunk); 54 } 55 log_trace(gc, metaspace, freelist, blocks)("returning block at " INTPTR_FORMAT " size = " 56 SIZE_FORMAT, p2i(free_chunk), word_size); 57 } 58 59 MetaWord* BlockFreelist::get_block(size_t word_size) { 60 assert(word_size >= SmallBlocks::small_block_min_size(), "never get dark matter"); 61 62 // Try small_blocks first. 63 if (word_size < SmallBlocks::small_block_max_size()) { 64 // Don't create small_blocks() until needed. small_blocks() allocates the small block list for 65 // this space manager. 66 MetaWord* new_block = (MetaWord*) small_blocks()->get_block(word_size); 67 if (new_block != NULL) { 68 log_trace(gc, metaspace, freelist, blocks)("getting block at " INTPTR_FORMAT " size = " SIZE_FORMAT, 69 p2i(new_block), word_size); 70 return new_block; 71 } 72 } 73 74 if (word_size < BlockFreelist::min_dictionary_size()) { 75 // If allocation in small blocks fails, this is Dark Matter. Too small for dictionary. 76 return NULL; 77 } 78 79 Metablock* free_block = dictionary()->get_chunk(word_size); 80 if (free_block == NULL) { 81 return NULL; 82 } 83 84 const size_t block_size = free_block->size(); 85 if (block_size > WasteMultiplier * word_size) { 86 return_block((MetaWord*)free_block, block_size); 87 return NULL; 88 } 89 90 MetaWord* new_block = (MetaWord*)free_block; 91 assert(block_size >= word_size, "Incorrect size of block from freelist"); 92 const size_t unused = block_size - word_size; 93 if (unused >= SmallBlocks::small_block_min_size()) { 94 return_block(new_block + word_size, unused); 95 } 96 97 log_trace(gc, metaspace, freelist, blocks)("getting block at " INTPTR_FORMAT " size = " SIZE_FORMAT, 98 p2i(new_block), word_size); 99 return new_block; 100 } 101 102 void BlockFreelist::print_on(outputStream* st) const { 103 dictionary()->print_free_lists(st); 104 if (_small_blocks != NULL) { 105 _small_blocks->print_on(st); 106 } 107 } 108 109 } // namespace metaspace 110 } // namespace internals