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 #include "precompiled.hpp" 25 26 27 #include "memory/metaspace/chunkAllocSequence.hpp" 28 #include "memory/metaspace/chunkLevel.hpp" 29 #include "memory/metaspace/chunkManager.hpp" 30 #include "memory/metaspace/metachunk.hpp" 31 #include "runtime/mutexLocker.hpp" 32 #include "utilities/debug.hpp" 33 #include "utilities/globalDefinitions.hpp" 34 35 namespace metaspace { 36 37 // Creates a chunk manager with a given name (which is for debug purposes only) 38 // and an associated space list which will be used to request new chunks from 39 // (see get_chunk()) 40 ChunkManager::ChunkManager(const char* name, VirtualSpaceList* space_list) 41 : _vs_list(space_list) 42 , _name(name) 43 , _chunks {} 44 , _num_chunks {} 45 , _total_word_size(0) 46 , _total_num_chunks(0) 47 { 48 } 49 50 void ChunkManager::account_for_added_chunk(const Metachunk* c) { 51 assert_lock_strong(MetaspaceExpand_lock); 52 53 const chklvl_t lvl = c->level(); 54 chklvl::check_valid_level(lvl); 55 56 _total_num_chunks ++; 57 _total_word_size += chklvl::word_size_for_level(lvl); 58 _num_chunks[lvl] ++; 59 } 60 61 void ChunkManager::account_for_removed_chunk(const Metachunk* c) { 62 assert_lock_strong(MetaspaceExpand_lock); 63 64 const chklvl_t lvl = c->level(); 65 chklvl::check_valid_level(lvl); 66 67 assert(_total_num_chunks > 0, "Sanity."); 68 _total_num_chunks --; 69 const size_t word_size = chklvl::word_size_for_level(lvl); 70 assert(_total_word_size >= word_size, "Sanity."); 71 _total_word_size -= chklvl::word_size_for_level(lvl); 72 assert(_num_chunks[lvl] > 0, "Sanity."); 73 _num_chunks[lvl] --; 74 } 75 76 77 // Remove a chunk of the given level from its freelist, and adjust accounting. 78 // If no chunk of this given level is free, return NULL. 79 Metachunk* ChunkManager::get_chunk_simple(chklvl_t level) { 80 81 assert_lock_strong(MetaspaceExpand_lock); 82 chklvl::check_valid_level(level); 83 84 Metachunk* c = _chunks[level]; 85 if (c != NULL) { 86 account_for_removed_chunk(c); 87 } 88 return c; 89 90 } 91 92 93 94 95 // Return a chunk to the ChunkManager and adjust accounting. May merge chunk 96 // with neighbors. 97 // Happens after a Classloader was unloaded and releases its metaspace chunks. 98 // !! Note: this may invalidate the chunk. Do not access the chunk after 99 // this function returns !! 100 void ChunkManager::return_chunk(Metachunk* chunk) { 101 102 103 } 104 105 106 // Remove the given chunk from its free list and adjust accounting. 107 // (Called during VirtualSpaceNode purging which happens during a Metaspace GC.) 108 void ChunkManager::remove_chunk(Metachunk* chunk) { 109 assert_lock_strong(MetaspaceExpand_lock); 110 chunk->remove_from_list(); 111 account_for_removed_chunk(chunk); 112 } 113 114 115 116 117 } // namespace metaspace 118 119 120