1 /* 2 * Copyright (c) 2001, 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 25 #ifndef SHARE_VM_GC_SHARED_COLLECTORPOLICY_HPP 26 #define SHARE_VM_GC_SHARED_COLLECTORPOLICY_HPP 27 28 #include "gc/shared/barrierSet.hpp" 29 #include "gc/shared/cardTableRS.hpp" 30 #include "gc/shared/generationSpec.hpp" 31 #include "memory/allocation.hpp" 32 #include "utilities/macros.hpp" 33 34 // This class (or more correctly, subtypes of this class) 35 // are used to define global garbage collector attributes. 36 // This includes initialization of generations and any other 37 // shared resources they may need. 38 // 39 // In general, all flag adjustment and validation should be 40 // done in initialize_flags(), which is called prior to 41 // initialize_size_info(). 42 // 43 // This class is not fully developed yet. As more collector(s) 44 // are added, it is expected that we will come across further 45 // behavior that requires global attention. The correct place 46 // to deal with those issues is this class. 47 48 // Forward declarations. 49 class GenCollectorPolicy; 50 class AdaptiveSizePolicy; 51 #if INCLUDE_ALL_GCS 52 class ConcurrentMarkSweepPolicy; 53 class G1CollectorPolicy; 54 #endif // INCLUDE_ALL_GCS 55 56 class MarkSweepPolicy; 57 58 class CollectorPolicy : public CHeapObj<mtGC> { 59 protected: 60 virtual void initialize_alignments() = 0; 61 virtual void initialize_flags(); 62 virtual void initialize_size_info(); 63 64 DEBUG_ONLY(virtual void assert_flags();) 65 DEBUG_ONLY(virtual void assert_size_info();) 66 67 size_t _initial_heap_byte_size; 68 size_t _max_heap_byte_size; 69 size_t _min_heap_byte_size; 70 71 size_t _space_alignment; 72 size_t _heap_alignment; 73 74 CollectorPolicy(); 75 76 public: 77 void initialize_all() { 78 initialize_alignments(); 79 initialize_flags(); 80 initialize_size_info(); 81 } 82 83 // Return maximum heap alignment that may be imposed by the policy. 84 static size_t compute_heap_alignment(); 85 86 size_t space_alignment() { return _space_alignment; } 87 size_t heap_alignment() { return _heap_alignment; } 88 89 size_t initial_heap_byte_size() { return _initial_heap_byte_size; } 90 size_t max_heap_byte_size() { return _max_heap_byte_size; } 91 size_t min_heap_byte_size() { return _min_heap_byte_size; } 92 }; 93 94 class GenCollectorPolicy : public CollectorPolicy { 95 friend class TestGenCollectorPolicy; 96 friend class VMStructs; 97 98 protected: 99 size_t _min_young_size; 100 size_t _initial_young_size; 101 size_t _max_young_size; 102 size_t _min_old_size; 103 size_t _initial_old_size; 104 size_t _max_old_size; 105 106 // _gen_alignment and _space_alignment will have the same value most of the 107 // time. When using large pages they can differ. 108 size_t _gen_alignment; 109 110 void initialize_flags(); 111 void initialize_size_info(); 112 113 DEBUG_ONLY(void assert_flags();) 114 DEBUG_ONLY(void assert_size_info();) 115 116 // Compute max heap alignment. 117 size_t compute_max_alignment(); 118 119 // Scale the base_size by NewRatio according to 120 // result = base_size / (NewRatio + 1) 121 // and align by min_alignment() 122 size_t scale_by_NewRatio_aligned(size_t base_size); 123 124 // Bound the value by the given maximum minus the min_alignment. 125 size_t bound_minus_alignment(size_t desired_size, size_t maximum_size); 126 127 public: 128 GenCollectorPolicy(); 129 130 // Accessors 131 size_t min_young_size() { return _min_young_size; } 132 size_t initial_young_size() { return _initial_young_size; } 133 size_t max_young_size() { return _max_young_size; } 134 size_t gen_alignment() { return _gen_alignment; } 135 size_t min_old_size() { return _min_old_size; } 136 size_t initial_old_size() { return _initial_old_size; } 137 size_t max_old_size() { return _max_old_size; } 138 139 size_t young_gen_size_lower_bound(); 140 141 size_t old_gen_size_lower_bound(); 142 }; 143 144 class MarkSweepPolicy : public GenCollectorPolicy { 145 protected: 146 void initialize_alignments(); 147 148 public: 149 MarkSweepPolicy() {} 150 }; 151 152 #endif // SHARE_VM_GC_SHARED_COLLECTORPOLICY_HPP