1 /*
2 * Copyright (c) 2020, 2024, 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 "cds/cdsConfig.hpp"
27 #include "cds/serializeClosure.hpp"
28 #include "classfile/classLoaderData.inline.hpp"
29 #include "classfile/classLoaderDataShared.hpp"
30 #include "classfile/moduleEntry.hpp"
31 #include "classfile/packageEntry.hpp"
32 #include "classfile/systemDictionary.hpp"
33 #include "logging/log.hpp"
34 #include "runtime/handles.inline.hpp"
35
36 #if INCLUDE_CDS_JAVA_HEAP
37
38 bool ClassLoaderDataShared::_full_module_graph_loaded = false;
39
40 class ArchivedClassLoaderData {
41 Array<PackageEntry*>* _packages;
42 Array<ModuleEntry*>* _modules;
43
44 void assert_valid(ClassLoaderData* loader_data) {
45 // loader_data may be null if the boot layer has loaded no modules for the platform or
46 // system loaders (e.g., if you create a custom JDK image with only java.base).
47 if (loader_data != nullptr) {
48 assert(!loader_data->has_class_mirror_holder(),
49 "loaders for non-strong hidden classes not supported");
50 }
51 }
52 public:
53 ArchivedClassLoaderData() : _packages(nullptr), _modules(nullptr) {}
54
55 void iterate_symbols(ClassLoaderData* loader_data, MetaspaceClosure* closure);
56 void allocate(ClassLoaderData* loader_data);
57 void init_archived_entries(ClassLoaderData* loader_data);
58
59 void serialize(SerializeClosure* f) {
60 f->do_ptr(&_packages);
61 f->do_ptr(&_modules);
62 }
63
64 void restore(ClassLoaderData* loader_data, bool do_entries, bool do_oops);
65 void clear_archived_oops();
66 };
67
68 static ArchivedClassLoaderData _archived_boot_loader_data;
69 static ArchivedClassLoaderData _archived_platform_loader_data;
70 static ArchivedClassLoaderData _archived_system_loader_data;
71 static ModuleEntry* _archived_javabase_moduleEntry = nullptr;
72
73 void ArchivedClassLoaderData::iterate_symbols(ClassLoaderData* loader_data, MetaspaceClosure* closure) {
74 assert(CDSConfig::is_dumping_full_module_graph(), "must be");
75 assert_valid(loader_data);
76 if (loader_data != nullptr) {
77 loader_data->packages()->iterate_symbols(closure);
78 loader_data->modules() ->iterate_symbols(closure);
79 }
80 }
81
82 void ArchivedClassLoaderData::allocate(ClassLoaderData* loader_data) {
83 assert(CDSConfig::is_dumping_full_module_graph(), "must be");
84 assert_valid(loader_data);
85 if (loader_data != nullptr) {
86 // We can't create hashtables at dump time because the hashcode depends on the
87 // address of the Symbols, which may be relocated at runtime due to ASLR.
88 // So we store the packages/modules in Arrays. At runtime, we create
89 // the hashtables using these arrays.
90 _packages = loader_data->packages()->allocate_archived_entries();
91 _modules = loader_data->modules() ->allocate_archived_entries();
92 }
93 }
94
95 void ArchivedClassLoaderData::init_archived_entries(ClassLoaderData* loader_data) {
96 assert(CDSConfig::is_dumping_full_module_graph(), "must be");
97 assert_valid(loader_data);
98 if (loader_data != nullptr) {
99 loader_data->packages()->init_archived_entries(_packages);
100 loader_data->modules() ->init_archived_entries(_modules);
101 }
102 }
103
104 void ArchivedClassLoaderData::restore(ClassLoaderData* loader_data, bool do_entries, bool do_oops) {
105 assert(UseSharedSpaces, "must be");
106 assert_valid(loader_data);
107 if (_modules != nullptr) { // Could be null if we have archived no modules for platform/system loaders
108 ModuleEntryTable* modules = loader_data->modules();
109 PackageEntryTable* packages = loader_data->packages();
110
111 MutexLocker m1(Module_lock);
112 if (do_entries) {
113 modules->load_archived_entries(loader_data, _modules);
114 packages->load_archived_entries(_packages);
115 }
116 if (do_oops) {
117 modules->restore_archived_oops(loader_data, _modules);
118 }
119 }
120 }
121
122 void ArchivedClassLoaderData::clear_archived_oops() {
123 assert(UseSharedSpaces, "must be");
124 if (_modules != nullptr) {
125 for (int i = 0; i < _modules->length(); i++) {
126 _modules->at(i)->clear_archived_oops();
127 }
128 }
129 }
130
131 // ------------------------------
132
133 static ClassLoaderData* null_class_loader_data() {
134 ClassLoaderData* loader_data = ClassLoaderData::the_null_class_loader_data();
135 assert(loader_data != nullptr, "must be");
136 return loader_data;
137 }
138
139 static ClassLoaderData* java_platform_loader_data_or_null() {
140 return ClassLoaderData::class_loader_data_or_null(SystemDictionary::java_platform_loader());
141 }
142
143 static ClassLoaderData* java_system_loader_data_or_null() {
144 return ClassLoaderData::class_loader_data_or_null(SystemDictionary::java_system_loader());
145 }
146
147 void ClassLoaderDataShared::iterate_symbols(MetaspaceClosure* closure) {
148 assert(CDSConfig::is_dumping_full_module_graph(), "must be");
149 _archived_boot_loader_data.iterate_symbols (null_class_loader_data(), closure);
150 _archived_platform_loader_data.iterate_symbols(java_platform_loader_data_or_null(), closure);
151 _archived_system_loader_data.iterate_symbols (java_system_loader_data_or_null(), closure);
152 }
153
154 void ClassLoaderDataShared::allocate_archived_tables() {
155 assert(CDSConfig::is_dumping_full_module_graph(), "must be");
156 _archived_boot_loader_data.allocate (null_class_loader_data());
157 _archived_platform_loader_data.allocate(java_platform_loader_data_or_null());
158 _archived_system_loader_data.allocate (java_system_loader_data_or_null());
159 }
160
161 void ClassLoaderDataShared::init_archived_tables() {
162 assert(CDSConfig::is_dumping_full_module_graph(), "must be");
163 _archived_boot_loader_data.init_archived_entries (null_class_loader_data());
164 _archived_platform_loader_data.init_archived_entries(java_platform_loader_data_or_null());
165 _archived_system_loader_data.init_archived_entries (java_system_loader_data_or_null());
166 _archived_javabase_moduleEntry = ModuleEntry::get_archived_entry(ModuleEntryTable::javabase_moduleEntry());
167 }
168
169 void ClassLoaderDataShared::serialize(SerializeClosure* f) {
170 _archived_boot_loader_data.serialize(f);
171 _archived_platform_loader_data.serialize(f);
172 _archived_system_loader_data.serialize(f);
173 f->do_ptr(&_archived_javabase_moduleEntry);
174
175 if (f->reading() && CDSConfig::is_using_full_module_graph()) {
176 // Must be done before ClassLoader::create_javabase()
177 _archived_boot_loader_data.restore(null_class_loader_data(), true, false);
178 ModuleEntryTable::set_javabase_moduleEntry(_archived_javabase_moduleEntry);
179 log_info(cds)("use_full_module_graph = true; java.base = " INTPTR_FORMAT,
180 p2i(_archived_javabase_moduleEntry));
181 }
182 }
183
184 void ClassLoaderDataShared::clear_archived_oops() {
185 assert(!CDSConfig::is_using_full_module_graph(), "must be");
186 _archived_boot_loader_data.clear_archived_oops();
187 _archived_platform_loader_data.clear_archived_oops();
188 _archived_system_loader_data.clear_archived_oops();
189 }
190
191 oop ClassLoaderDataShared::restore_archived_oops_for_null_class_loader_data() {
192 assert(CDSConfig::is_using_full_module_graph(), "must be");
193 _archived_boot_loader_data.restore(null_class_loader_data(), false, true);
194 return _archived_javabase_moduleEntry->module();
195 }
196
197 void ClassLoaderDataShared::restore_java_platform_loader_from_archive(ClassLoaderData* loader_data) {
198 assert(CDSConfig::is_using_full_module_graph(), "must be");
199 _archived_platform_loader_data.restore(loader_data, true, true);
200 }
201
202 void ClassLoaderDataShared::restore_java_system_loader_from_archive(ClassLoaderData* loader_data) {
203 assert(CDSConfig::is_using_full_module_graph(), "must be");
204 _archived_system_loader_data.restore(loader_data, true, true);
205 _full_module_graph_loaded = true;
206 }
207
208 #endif // INCLUDE_CDS_JAVA_HEAP