1 /*
2 * Copyright (c) 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 #include "precompiled.hpp"
26 #include "gc/shared/gcConfig.hpp"
27 #include "runtime/java.hpp"
28 #include "runtime/os.hpp"
29 #include "utilities/macros.hpp"
30 #if INCLUDE_CMSGC
31 #include "gc/cms/cmsArguments.hpp"
32 #endif
33 #if INCLUDE_G1GC
34 #include "gc/g1/g1Arguments.hpp"
35 #endif
36 #if INCLUDE_PARALLELGC
37 #include "gc/parallel/parallelArguments.hpp"
38 #endif
39 #if INCLUDE_SERIALGC
40 #include "gc/serial/serialArguments.hpp"
41 #endif
42
43 struct SupportedGC {
44 bool& _flag;
45 CollectedHeap::Name _name;
46 GCArguments& _arguments;
47
48 SupportedGC(bool& flag, CollectedHeap::Name name, GCArguments& arguments) :
49 _flag(flag), _name(name), _arguments(arguments) {}
50 };
51
52 CMSGC_ONLY(static CMSArguments cmsArguments;)
53 G1GC_ONLY(static G1Arguments g1Arguments;)
54 PARALLELGC_ONLY(static ParallelArguments parallelArguments;)
55 SERIALGC_ONLY(static SerialArguments serialArguments;)
56
57 // Table of supported GCs, for translating between command
58 // line flag, CollectedHeap::Name and GCArguments instance.
59 static const SupportedGC SupportedGCs[] = {
60 CMSGC_ONLY_ARG(SupportedGC(UseConcMarkSweepGC, CollectedHeap::CMS, cmsArguments))
61 G1GC_ONLY_ARG(SupportedGC(UseG1GC, CollectedHeap::G1, g1Arguments))
62 PARALLELGC_ONLY_ARG(SupportedGC(UseParallelGC, CollectedHeap::Parallel, parallelArguments))
63 PARALLELGC_ONLY_ARG(SupportedGC(UseParallelOldGC, CollectedHeap::Parallel, parallelArguments))
64 SERIALGC_ONLY_ARG(SupportedGC(UseSerialGC, CollectedHeap::Serial, serialArguments))
65 };
66
67 GCArguments* GCConfig::_arguments = NULL;
68 bool GCConfig::_gc_selected_ergonomically = false;
69
70 void GCConfig::select_gc_ergonomically() {
71 if (os::is_server_class_machine()) {
72 #if INCLUDE_G1GC
73 FLAG_SET_ERGO_IF_DEFAULT(bool, UseG1GC, true);
74 #elif INCLUDE_PARALLELGC
75 FLAG_SET_ERGO_IF_DEFAULT(bool, UseParallelGC, true);
76 #elif INCLUDE_SERIALGC
77 FLAG_SET_ERGO_IF_DEFAULT(bool, UseSerialGC, true);
78 #endif
79 } else {
80 #if INCLUDE_SERIALGC
81 FLAG_SET_ERGO_IF_DEFAULT(bool, UseSerialGC, true);
82 #endif
83 }
84
85 NOT_CMSGC(UNSUPPORTED_OPTION(UseConcMarkSweepGC));
86 NOT_G1GC(UNSUPPORTED_OPTION(UseG1GC);)
87 NOT_PARALLELGC(UNSUPPORTED_OPTION(UseParallelGC);)
88 NOT_PARALLELGC(UNSUPPORTED_OPTION(UseParallelOldGC));
89 NOT_SERIALGC(UNSUPPORTED_OPTION(UseSerialGC);)
90 }
91
92 bool GCConfig::is_no_gc_selected() {
93 for (size_t i = 0; i < ARRAY_SIZE(SupportedGCs); i++) {
94 if (SupportedGCs[i]._flag) {
95 return false;
96 }
97 }
98
99 return true;
100 }
101
102 bool GCConfig::is_exactly_one_gc_selected() {
103 CollectedHeap::Name selected = CollectedHeap::None;
104
105 for (size_t i = 0; i < ARRAY_SIZE(SupportedGCs); i++) {
106 if (SupportedGCs[i]._flag) {
107 if (SupportedGCs[i]._name == selected || selected == CollectedHeap::None) {
108 // Selected
109 selected = SupportedGCs[i]._name;
110 } else {
111 // More than one selected
112 return false;
113 }
114 }
115 }
116
117 return selected != CollectedHeap::None;
118 }
119
120 GCArguments* GCConfig::select_gc() {
121 if (is_no_gc_selected()) {
122 // Try select GC ergonomically
123 select_gc_ergonomically();
124
125 if (is_no_gc_selected()) {
126 // Failed to select GC ergonomically
127 vm_exit_during_initialization("Garbage collector not selected "
128 "(default collector explicitly disabled)", NULL);
129 }
130
131 // Succeeded to select GC ergonomically
132 _gc_selected_ergonomically = true;
133 }
134
135 if (is_exactly_one_gc_selected()) {
136 // Exacly one GC selected
137 for (size_t i = 0; i < ARRAY_SIZE(SupportedGCs); i++) {
138 if (SupportedGCs[i]._flag) {
139 return &SupportedGCs[i]._arguments;
140 }
141 }
142 }
143
144 // More than one GC selected
145 vm_exit_during_initialization("Multiple garbage collectors selected", NULL);
146
147 return NULL;
148 }
149
150 void GCConfig::initialize() {
151 assert(_arguments == NULL, "Already initialized");
152 _arguments = select_gc();
153 }
154
155 bool GCConfig::is_gc_supported(CollectedHeap::Name name) {
156 for (size_t i = 0; i < ARRAY_SIZE(SupportedGCs); i++) {
157 if (SupportedGCs[i]._name == name) {
158 // Supported
159 return true;
160 }
161 }
162
163 // Not supported
164 return false;
165 }
166
167 bool GCConfig::is_gc_selected(CollectedHeap::Name name) {
168 for (size_t i = 0; i < ARRAY_SIZE(SupportedGCs); i++) {
169 if (SupportedGCs[i]._name == name && SupportedGCs[i]._flag) {
170 // Selected
171 return true;
172 }
173 }
174
175 // Not selected
176 return false;
177 }
178
179 bool GCConfig::is_gc_selected_ergonomically() {
180 return _gc_selected_ergonomically;
181 }
182
183 GCArguments* GCConfig::arguments() {
184 assert(_arguments != NULL, "Not initialized");
185 return _arguments;
186 }