1 /*
2 * Copyright (c) 2001, 2010, 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_MEMORY_ADAPTIVEFREELIST_HPP
26 #define SHARE_VM_MEMORY_ADAPTIVEFREELIST_HPP
27
28 #include "memory/freeList.hpp"
29 #include "gc_implementation/shared/allocationStats.hpp"
30
31 class CompactibleFreeListSpace;
32
33 // A class for maintaining a free list of Chunk's. The FreeList
34 // maintains a the structure of the list (head, tail, etc.) plus
35 // statistics for allocations from the list. The links between items
36 // are not part of FreeList. The statistics are
37 // used to make decisions about coalescing Chunk's when they
38 // are swept during collection.
39 //
40 // See the corresponding .cpp file for a description of the specifics
41 // for that implementation.
42
43 class Mutex;
44
45 template <class Chunk>
46 class AdaptiveFreeList : public FreeList<Chunk> {
47 friend class CompactibleFreeListSpace;
48 friend class VMStructs;
49 // friend class PrintTreeCensusClosure<Chunk, FreeList_t>;
50
51 size_t _hint; // next larger size list with a positive surplus
52
53 AllocationStats _allocation_stats; // allocation-related statistics
54
55 public:
56
57 AdaptiveFreeList();
58 AdaptiveFreeList(Chunk* fc);
59
60 using FreeList<Chunk>::assert_proper_lock_protection;
61 #ifdef ASSERT
62 using FreeList<Chunk>::protecting_lock;
63 #endif
64 using FreeList<Chunk>::count;
65 using FreeList<Chunk>::size;
66 using FreeList<Chunk>::verify_chunk_in_free_list;
67 using FreeList<Chunk>::getFirstNChunksFromList;
68 using FreeList<Chunk>::print_on;
69 void return_chunk_at_head(Chunk* fc, bool record_return, bool deallocate_pages);
70 void return_chunk_at_head(Chunk* fc);
71 void return_chunk_at_tail(Chunk* fc, bool record_return, bool deallocate_pages);
72 void return_chunk_at_tail(Chunk* fc);
73 using FreeList<Chunk>::return_chunk_at_tail;
74 using FreeList<Chunk>::remove_chunk;
75 using FreeList<Chunk>::prepend;
76 using FreeList<Chunk>::print_labels_on;
77 using FreeList<Chunk>::get_chunk_at_head;
78
79 // Initialize.
80 void initialize();
81
82 // Reset the head, tail, hint, and count of a free list.
83 void reset(size_t hint);
84
85 void assert_proper_lock_protection_work() const PRODUCT_RETURN;
86
87 void print_on(outputStream* st, const char* c = NULL) const;
88
89 size_t hint() const {
90 return _hint;
91 }
92 void set_hint(size_t v) {
93 assert_proper_lock_protection();
94 assert(v == 0 || size() < v, "Bad hint");
95 _hint = v;
96 }
97
98 size_t get_better_size();
99
100 // Accessors for statistics
101 void init_statistics(bool split_birth = false);
102
103 AllocationStats* allocation_stats() {
104 assert_proper_lock_protection();
105 return &_allocation_stats;
106 }
107
108 ssize_t desired() const {
109 return _allocation_stats.desired();
110 }
111 void set_desired(ssize_t v) {
112 assert_proper_lock_protection();
113 _allocation_stats.set_desired(v);
114 }
115 void compute_desired(float inter_sweep_current,
116 float inter_sweep_estimate,
117 float intra_sweep_estimate) {
118 assert_proper_lock_protection();
119 _allocation_stats.compute_desired(count(),
120 inter_sweep_current,
121 inter_sweep_estimate,
122 intra_sweep_estimate);
123 }
124 ssize_t coal_desired() const {
125 return _allocation_stats.coal_desired();
126 }
127 void set_coal_desired(ssize_t v) {
128 assert_proper_lock_protection();
129 _allocation_stats.set_coal_desired(v);
130 }
131
132 ssize_t surplus() const {
133 return _allocation_stats.surplus();
134 }
135 void set_surplus(ssize_t v) {
136 assert_proper_lock_protection();
137 _allocation_stats.set_surplus(v);
138 }
139 void increment_surplus() {
140 assert_proper_lock_protection();
141 _allocation_stats.increment_surplus();
142 }
143 void decrement_surplus() {
144 assert_proper_lock_protection();
145 _allocation_stats.decrement_surplus();
146 }
147
148 ssize_t bfr_surp() const {
149 return _allocation_stats.bfr_surp();
150 }
151 void set_bfr_surp(ssize_t v) {
152 assert_proper_lock_protection();
153 _allocation_stats.set_bfr_surp(v);
154 }
155 ssize_t prev_sweep() const {
156 return _allocation_stats.prev_sweep();
157 }
158 void set_prev_sweep(ssize_t v) {
159 assert_proper_lock_protection();
160 _allocation_stats.set_prev_sweep(v);
161 }
162 ssize_t before_sweep() const {
163 return _allocation_stats.before_sweep();
164 }
165 void set_before_sweep(ssize_t v) {
166 assert_proper_lock_protection();
167 _allocation_stats.set_before_sweep(v);
168 }
169
170 ssize_t coal_births() const {
171 return _allocation_stats.coal_births();
172 }
173 void set_coal_births(ssize_t v) {
174 assert_proper_lock_protection();
175 _allocation_stats.set_coal_births(v);
176 }
177 void increment_coal_births() {
178 assert_proper_lock_protection();
179 _allocation_stats.increment_coal_births();
180 }
181
182 ssize_t coal_deaths() const {
183 return _allocation_stats.coal_deaths();
184 }
185 void set_coal_deaths(ssize_t v) {
186 assert_proper_lock_protection();
187 _allocation_stats.set_coal_deaths(v);
188 }
189 void increment_coal_deaths() {
190 assert_proper_lock_protection();
191 _allocation_stats.increment_coal_deaths();
192 }
193
194 ssize_t split_births() const {
195 return _allocation_stats.split_births();
196 }
197 void set_split_births(ssize_t v) {
198 assert_proper_lock_protection();
199 _allocation_stats.set_split_births(v);
200 }
201 void increment_split_births() {
202 assert_proper_lock_protection();
203 _allocation_stats.increment_split_births();
204 }
205
206 ssize_t split_deaths() const {
207 return _allocation_stats.split_deaths();
208 }
209 void set_split_deaths(ssize_t v) {
210 assert_proper_lock_protection();
211 _allocation_stats.set_split_deaths(v);
212 }
213 void increment_split_deaths() {
214 assert_proper_lock_protection();
215 _allocation_stats.increment_split_deaths();
216 }
217
218 #ifndef PRODUCT
219 // For debugging. The "_returned_bytes" in all the lists are summed
220 // and compared with the total number of bytes swept during a
221 // collection.
222 size_t returned_bytes() const { return _allocation_stats.returned_bytes(); }
223 void set_returned_bytes(size_t v) { _allocation_stats.set_returned_bytes(v); }
224 void increment_returned_bytes_by(size_t v) {
225 _allocation_stats.set_returned_bytes(_allocation_stats.returned_bytes() + v);
226 }
227 // Stats verification
228 void verify_stats() const;
229 #endif // NOT PRODUCT
230 };
231
232 #endif // SHARE_VM_MEMORY_ADAPTIVEFREELIST_HPP