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/globals_extension.hpp"
28 #include "runtime/java.hpp"
29 #include "runtime/os.hpp"
30 #include "utilities/macros.hpp"
31 #if INCLUDE_CMSGC
32 #include "gc/cms/cmsArguments.hpp"
33 #endif
34 #if INCLUDE_EPSILONGC
35 #include "gc/epsilon/epsilonArguments.hpp"
36 #endif
37 #if INCLUDE_G1GC
38 #include "gc/g1/g1Arguments.hpp"
39 #endif
40 #if INCLUDE_PARALLELGC
41 #include "gc/parallel/parallelArguments.hpp"
42 #endif
43 #if INCLUDE_SERIALGC
44 #include "gc/serial/serialArguments.hpp"
45 #endif
46 #if INCLUDE_ZGC
47 #include "gc/z/zArguments.hpp"
48 #endif
49
50 struct SupportedGC {
51 bool& _flag;
52 CollectedHeap::Name _name;
53 GCArguments& _arguments;
54 const char* _hs_err_name;
55
56 SupportedGC(bool& flag, CollectedHeap::Name name, GCArguments& arguments, const char* hs_err_name) :
57 _flag(flag), _name(name), _arguments(arguments), _hs_err_name(hs_err_name) {}
58 };
59
60 CMSGC_ONLY(static CMSArguments cmsArguments;)
61 EPSILONGC_ONLY(static EpsilonArguments epsilonArguments;)
62 G1GC_ONLY(static G1Arguments g1Arguments;)
63 PARALLELGC_ONLY(static ParallelArguments parallelArguments;)
64 SERIALGC_ONLY(static SerialArguments serialArguments;)
65 ZGC_ONLY(static ZArguments zArguments;)
66
67 // Table of supported GCs, for translating between command
68 // line flag, CollectedHeap::Name and GCArguments instance.
69 static const SupportedGC SupportedGCs[] = {
70 CMSGC_ONLY_ARG(SupportedGC(UseConcMarkSweepGC, CollectedHeap::CMS, cmsArguments, "concurrent mark sweep gc"))
71 EPSILONGC_ONLY_ARG(SupportedGC(UseEpsilonGC, CollectedHeap::Epsilon, epsilonArguments, "epsilon gc"))
72 G1GC_ONLY_ARG(SupportedGC(UseG1GC, CollectedHeap::G1, g1Arguments, "g1 gc"))
73 PARALLELGC_ONLY_ARG(SupportedGC(UseParallelGC, CollectedHeap::Parallel, parallelArguments, "parallel gc"))
74 PARALLELGC_ONLY_ARG(SupportedGC(UseParallelOldGC, CollectedHeap::Parallel, parallelArguments, "parallel gc"))
75 SERIALGC_ONLY_ARG(SupportedGC(UseSerialGC, CollectedHeap::Serial, serialArguments, "serial gc"))
76 ZGC_ONLY_ARG(SupportedGC(UseZGC, CollectedHeap::Z, zArguments, "z gc"))
77 };
78
79 #define FOR_EACH_SUPPORTED_GC(var) \
80 for (const SupportedGC* var = &SupportedGCs[0]; var < &SupportedGCs[ARRAY_SIZE(SupportedGCs)]; var++)
81
82 #define FAIL_IF_SELECTED(option, enabled) \
83 if (option == enabled && FLAG_IS_CMDLINE(option)) { \
84 vm_exit_during_initialization(enabled ? \
85 "Option -XX:+" #option " not supported" : \
86 "Option -XX:-" #option " not supported"); \
87 }
88
89 GCArguments* GCConfig::_arguments = NULL;
90 bool GCConfig::_gc_selected_ergonomically = false;
91
92 void GCConfig::fail_if_unsupported_gc_is_selected() {
93 NOT_CMSGC( FAIL_IF_SELECTED(UseConcMarkSweepGC, true));
94 NOT_EPSILONGC( FAIL_IF_SELECTED(UseEpsilonGC, true));
95 NOT_G1GC( FAIL_IF_SELECTED(UseG1GC, true));
96 NOT_PARALLELGC(FAIL_IF_SELECTED(UseParallelGC, true));
97 NOT_PARALLELGC(FAIL_IF_SELECTED(UseParallelOldGC, true));
98 NOT_SERIALGC( FAIL_IF_SELECTED(UseSerialGC, true));
99 NOT_SERIALGC( FAIL_IF_SELECTED(UseParallelOldGC, false));
100 NOT_ZGC( FAIL_IF_SELECTED(UseZGC, true));
101 }
102
103 void GCConfig::select_gc_ergonomically() {
104 if (os::is_server_class_machine()) {
105 #if INCLUDE_G1GC
106 FLAG_SET_ERGO_IF_DEFAULT(bool, UseG1GC, true);
107 #elif INCLUDE_PARALLELGC
108 FLAG_SET_ERGO_IF_DEFAULT(bool, UseParallelGC, true);
109 #elif INCLUDE_SERIALGC
110 FLAG_SET_ERGO_IF_DEFAULT(bool, UseSerialGC, true);
111 #endif
112 } else {
113 #if INCLUDE_SERIALGC
114 FLAG_SET_ERGO_IF_DEFAULT(bool, UseSerialGC, true);
115 #endif
116 }
117 }
118
119 bool GCConfig::is_no_gc_selected() {
120 FOR_EACH_SUPPORTED_GC(gc) {
121 if (gc->_flag) {
122 return false;
123 }
124 }
125
126 return true;
127 }
128
129 bool GCConfig::is_exactly_one_gc_selected() {
130 CollectedHeap::Name selected = CollectedHeap::None;
131
132 FOR_EACH_SUPPORTED_GC(gc) {
133 if (gc->_flag) {
134 if (gc->_name == selected || selected == CollectedHeap::None) {
135 // Selected
136 selected = gc->_name;
137 } else {
138 // More than one selected
139 return false;
140 }
141 }
142 }
143
144 return selected != CollectedHeap::None;
145 }
146
147 GCArguments* GCConfig::select_gc() {
148 // Fail immediately if an unsupported GC is selected
149 fail_if_unsupported_gc_is_selected();
150
151 if (is_no_gc_selected()) {
152 // Try select GC ergonomically
153 select_gc_ergonomically();
154
155 if (is_no_gc_selected()) {
156 // Failed to select GC ergonomically
157 vm_exit_during_initialization("Garbage collector not selected "
158 "(default collector explicitly disabled)", NULL);
159 }
160
161 // Succeeded to select GC ergonomically
162 _gc_selected_ergonomically = true;
163 }
164
165 if (!is_exactly_one_gc_selected()) {
166 // More than one GC selected
167 vm_exit_during_initialization("Multiple garbage collectors selected", NULL);
168 }
169
170 // Exactly one GC selected
171 FOR_EACH_SUPPORTED_GC(gc) {
172 if (gc->_flag) {
173 return &gc->_arguments;
174 }
175 }
176
177 fatal("Should have found the selected GC");
178
179 return NULL;
180 }
181
182 void GCConfig::initialize() {
183 assert(_arguments == NULL, "Already initialized");
184 _arguments = select_gc();
185 }
186
187 bool GCConfig::is_gc_supported(CollectedHeap::Name name) {
188 FOR_EACH_SUPPORTED_GC(gc) {
189 if (gc->_name == name) {
190 // Supported
191 return true;
192 }
193 }
194
195 // Not supported
196 return false;
197 }
198
199 bool GCConfig::is_gc_selected(CollectedHeap::Name name) {
200 FOR_EACH_SUPPORTED_GC(gc) {
201 if (gc->_name == name && gc->_flag) {
202 // Selected
203 return true;
204 }
205 }
206
207 // Not selected
208 return false;
209 }
210
211 bool GCConfig::is_gc_selected_ergonomically() {
212 return _gc_selected_ergonomically;
213 }
214
215 const char* GCConfig::hs_err_name() {
216 if (is_exactly_one_gc_selected()) {
217 // Exacly one GC selected
218 FOR_EACH_SUPPORTED_GC(gc) {
219 if (gc->_flag) {
220 return gc->_hs_err_name;
221 }
222 }
223 }
224
225 // Zero or more than one GC selected
226 return "unknown gc";
227 }
228
229 const char* GCConfig::hs_err_name(CollectedHeap::Name name) {
230 FOR_EACH_SUPPORTED_GC(gc) {
231 if (gc->_name == name) {
232 return gc->_hs_err_name;
233 }
234 }
235 return "unknown gc";
236 }
237
238 GCArguments* GCConfig::arguments() {
239 assert(_arguments != NULL, "Not initialized");
240 return _arguments;
241 }