1 /*
2 * Copyright (c) 2012, 2014, 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 #include "precompiled.hpp"
26 #include "gc_implementation/concurrentMarkSweep/adaptiveFreeList.hpp"
27 #include "gc_implementation/concurrentMarkSweep/freeChunk.hpp"
28 #include "gc_interface/collectedHeap.hpp"
29 #include "memory/freeBlockDictionary.hpp"
30 #include "runtime/globals.hpp"
31 #include "runtime/mutex.hpp"
32 #include "runtime/orderAccess.inline.hpp"
33 #include "runtime/vmThread.hpp"
34
35 template <>
36 void AdaptiveFreeList<FreeChunk>::print_on(outputStream* st, const char* c) const {
37 if (c != NULL) {
38 st->print("%16s", c);
39 } else {
40 st->print(SIZE_FORMAT_W(16), size());
41 }
42 st->print("\t"
43 SSIZE_FORMAT_W(14) "\t" SSIZE_FORMAT_W(14) "\t" SSIZE_FORMAT_W(14) "\t" SSIZE_FORMAT_W(14) "\t" SSIZE_FORMAT_W(14) "\t"
44 SSIZE_FORMAT_W(14) "\t" SSIZE_FORMAT_W(14) "\t" SSIZE_FORMAT_W(14) "\t" SSIZE_FORMAT_W(14) "\t" SSIZE_FORMAT_W(14) "\n",
45 bfr_surp(), surplus(), desired(), prev_sweep(), before_sweep(),
46 count(), coal_births(), coal_deaths(), split_births(), split_deaths());
47 }
48
49 template <class Chunk>
50 AdaptiveFreeList<Chunk>::AdaptiveFreeList() : FreeList<Chunk>(), _hint(0) {
51 init_statistics();
52 }
53
54 template <class Chunk>
55 void AdaptiveFreeList<Chunk>::initialize() {
56 FreeList<Chunk>::initialize();
57 set_hint(0);
58 init_statistics(true /* split_birth */);
59 }
60
61 template <class Chunk>
62 void AdaptiveFreeList<Chunk>::reset(size_t hint) {
63 FreeList<Chunk>::reset();
64 set_hint(hint);
65 }
66
67 template <class Chunk>
68 void AdaptiveFreeList<Chunk>::init_statistics(bool split_birth) {
69 _allocation_stats.initialize(split_birth);
70 }
71
72 template <class Chunk>
73 size_t AdaptiveFreeList<Chunk>::get_better_size() {
74
75 // A candidate chunk has been found. If it is already under
76 // populated and there is a hinT, REturn the hint(). Else
77 // return the size of this chunk.
78 if (surplus() <= 0) {
79 if (hint() != 0) {
80 return hint();
81 } else {
82 return size();
83 }
84 } else {
85 // This list has a surplus so use it.
86 return size();
87 }
88 }
89
90
91 template <class Chunk>
92 void AdaptiveFreeList<Chunk>::return_chunk_at_head(Chunk* chunk) {
93 assert_proper_lock_protection();
94 return_chunk_at_head(chunk, true);
95 }
96
97 template <class Chunk>
98 void AdaptiveFreeList<Chunk>::return_chunk_at_head(Chunk* chunk, bool record_return) {
99 FreeList<Chunk>::return_chunk_at_head(chunk, record_return);
100 #ifdef ASSERT
101 if (record_return) {
102 increment_returned_bytes_by(size()*HeapWordSize);
103 }
104 #endif
105 }
106
107 template <class Chunk>
108 void AdaptiveFreeList<Chunk>::return_chunk_at_tail(Chunk* chunk) {
109 AdaptiveFreeList<Chunk>::return_chunk_at_tail(chunk, true);
110 }
111
112 template <class Chunk>
113 void AdaptiveFreeList<Chunk>::return_chunk_at_tail(Chunk* chunk, bool record_return) {
114 FreeList<Chunk>::return_chunk_at_tail(chunk, record_return);
115 #ifdef ASSERT
116 if (record_return) {
117 increment_returned_bytes_by(size()*HeapWordSize);
118 }
119 #endif
120 }
121
122 #ifndef PRODUCT
123 template <class Chunk>
124 void AdaptiveFreeList<Chunk>::verify_stats() const {
125 // The +1 of the LH comparand is to allow some "looseness" in
126 // checking: we usually call this interface when adding a block
127 // and we'll subsequently update the stats; we cannot update the
128 // stats beforehand because in the case of the large-block BT
129 // dictionary for example, this might be the first block and
130 // in that case there would be no place that we could record
131 // the stats (which are kept in the block itself).
132 assert((_allocation_stats.prev_sweep() + _allocation_stats.split_births()
133 + _allocation_stats.coal_births() + 1) // Total Production Stock + 1
134 >= (_allocation_stats.split_deaths() + _allocation_stats.coal_deaths()
135 + (ssize_t)count()), // Total Current Stock + depletion
136 err_msg("FreeList " PTR_FORMAT " of size " SIZE_FORMAT
137 " violates Conservation Principle: "
138 "prev_sweep(" SIZE_FORMAT ")"
139 " + split_births(" SIZE_FORMAT ")"
140 " + coal_births(" SIZE_FORMAT ") + 1 >= "
141 " split_deaths(" SIZE_FORMAT ")"
142 " coal_deaths(" SIZE_FORMAT ")"
143 " + count(" SSIZE_FORMAT ")",
144 p2i(this), size(), _allocation_stats.prev_sweep(), _allocation_stats.split_births(),
145 _allocation_stats.coal_births(), _allocation_stats.split_deaths(),
146 _allocation_stats.coal_deaths(), count()));
147 }
148 #endif
149
150 // Needs to be after the definitions have been seen.
151 template class AdaptiveFreeList<FreeChunk>;