1 /* 2 * Copyright (c) 2001, 2008, 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 // A FreeBlockDictionary is an abstract superclass that will allow 26 // a number of alternative implementations in the future. 27 class FreeBlockDictionary: public CHeapObj { 28 public: 29 enum Dither { 30 atLeast, 31 exactly, 32 roughly 33 }; 34 enum DictionaryChoice { 35 dictionaryBinaryTree = 0, 36 dictionarySplayTree = 1, 37 dictionarySkipList = 2 38 }; 39 40 private: 41 NOT_PRODUCT(Mutex* _lock;) 42 43 public: 44 virtual void removeChunk(FreeChunk* fc) = 0; 45 virtual FreeChunk* getChunk(size_t size, Dither dither = atLeast) = 0; 46 virtual void returnChunk(FreeChunk* chunk) = 0; 47 virtual size_t totalChunkSize(debug_only(const Mutex* lock)) const = 0; 48 virtual size_t maxChunkSize() const = 0; 49 virtual size_t minSize() const = 0; 50 // Reset the dictionary to the initial conditions for a single 51 // block. 52 virtual void reset(HeapWord* addr, size_t size) = 0; 53 virtual void reset() = 0; 54 55 virtual void dictCensusUpdate(size_t size, bool split, bool birth) = 0; 56 virtual bool coalDictOverPopulated(size_t size) = 0; 57 virtual void beginSweepDictCensus(double coalSurplusPercent, 58 float inter_sweep_current, float inter_sweep_estimate, 59 float intra__sweep_current) = 0; 60 virtual void endSweepDictCensus(double splitSurplusPercent) = 0; 61 virtual FreeChunk* findLargestDict() const = 0; 62 // verify that the given chunk is in the dictionary. 63 virtual bool verifyChunkInFreeLists(FreeChunk* tc) const = 0; 64 65 // Sigma_{all_free_blocks} (block_size^2) 66 virtual double sum_of_squared_block_sizes() const = 0; 67 68 virtual FreeChunk* find_chunk_ends_at(HeapWord* target) const = 0; 69 virtual void inc_totalSize(size_t v) = 0; 70 virtual void dec_totalSize(size_t v) = 0; 71 72 NOT_PRODUCT ( 73 virtual size_t sumDictReturnedBytes() = 0; 74 virtual void initializeDictReturnedBytes() = 0; 75 virtual size_t totalCount() = 0; 76 ) 77 78 virtual void reportStatistics() const { 79 gclog_or_tty->print("No statistics available"); 80 } 81 82 virtual void printDictCensus() const = 0; 83 virtual void print_free_lists(outputStream* st) const = 0; 84 85 virtual void verify() const = 0; 86 87 Mutex* par_lock() const PRODUCT_RETURN0; 88 void set_par_lock(Mutex* lock) PRODUCT_RETURN; 89 void verify_par_locked() const PRODUCT_RETURN; 90 };