1 /*
2 * Copyright (c) 2012, 2025, 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.
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23 */
24
25 #ifndef SHARE_CDS_METASPACESHARED_HPP
26 #define SHARE_CDS_METASPACESHARED_HPP
27
28 #include "memory/allocation.hpp"
29 #include "memory/memRegion.hpp"
30 #include "memory/reservedSpace.hpp"
31 #include "memory/virtualspace.hpp"
32 #include "oops/oop.hpp"
33 #include "utilities/macros.hpp"
34
35 class ArchiveBuilder;
36 class ArchiveHeapInfo;
37 class FileMapInfo;
38 class Method;
39 class outputStream;
40 class SerializeClosure;
41 class StaticArchiveBuilder;
42
43 template<class E> class Array;
44
45 enum MapArchiveResult {
46 MAP_ARCHIVE_SUCCESS,
47 MAP_ARCHIVE_MMAP_FAILURE,
48 MAP_ARCHIVE_OTHER_FAILURE
49 };
50
51 // Class Data Sharing Support
52 class MetaspaceShared : AllStatic {
53 static ReservedSpace _symbol_rs; // used only during -Xshare:dump
54 static VirtualSpace _symbol_vs; // used only during -Xshare:dump
55 static bool _archive_loading_failed;
56 static bool _remapped_readwrite;
57 static void* _shared_metaspace_static_top;
58 static intx _relocation_delta;
59 static char* _requested_base_address;
60 static bool _use_optimized_module_handling;
61 static Array<Method*>* _archived_method_handle_intrinsics;
62
63 public:
64 enum {
65 // core archive spaces
66 rw = 0, // read-write shared space
67 ro = 1, // read-only shared space
68 bm = 2, // relocation bitmaps (freed after file mapping is finished)
69 hp = 3, // heap region
70 num_core_region = 2, // rw and ro
71 n_regions = 4 // total number of regions
72 };
73
74 static void preload_and_dump(TRAPS) NOT_CDS_RETURN;
75 #ifdef _LP64
76 static void adjust_heap_sizes_for_dumping() NOT_CDS_JAVA_HEAP_RETURN;
77 #endif
78
79 private:
80 static void exercise_runtime_cds_code(TRAPS) NOT_CDS_RETURN;
81 static void preload_and_dump_impl(StaticArchiveBuilder& builder, TRAPS) NOT_CDS_RETURN;
82 static void preload_classes(TRAPS) NOT_CDS_RETURN;
83
84 public:
85 static Symbol* symbol_rs_base() {
86 return (Symbol*)_symbol_rs.base();
87 }
88
89 static void initialize_for_static_dump() NOT_CDS_RETURN;
90 static void initialize_runtime_shared_and_meta_spaces() NOT_CDS_RETURN;
91 static void post_initialize(TRAPS) NOT_CDS_RETURN;
92
93 static void print_on(outputStream* st);
94
95 static void set_archive_loading_failed() {
96 _archive_loading_failed = true;
97 }
98
99 static void initialize_shared_spaces() NOT_CDS_RETURN;
100
101 // Return true if given address is in the shared metaspace regions (i.e., excluding the
102 // mapped heap region.)
103 static bool is_in_shared_metaspace(const void* p) {
104 return MetaspaceObj::is_shared((const MetaspaceObj*)p);
105 }
106
107 static void set_shared_metaspace_range(void* base, void *static_top, void* top) NOT_CDS_RETURN;
108
109 static bool is_shared_dynamic(void* p) NOT_CDS_RETURN_(false);
110 static bool is_shared_static(void* p) NOT_CDS_RETURN_(false);
111
112 static void unrecoverable_loading_error(const char* message = nullptr);
113 static void unrecoverable_writing_error(const char* message = nullptr);
114 static void writing_error(const char* message = nullptr);
115
116 static void make_method_handle_intrinsics_shareable() NOT_CDS_RETURN;
117 static void write_method_handle_intrinsics() NOT_CDS_RETURN;
118 static Array<Method*>* archived_method_handle_intrinsics() { return _archived_method_handle_intrinsics; }
119 static void early_serialize(SerializeClosure* sc) NOT_CDS_RETURN;
120 static void serialize(SerializeClosure* sc) NOT_CDS_RETURN;
121
122 // JVM/TI RedefineClasses() support:
123 // Remap the shared readonly space to shared readwrite, private if
124 // sharing is enabled. Simply returns true if sharing is not enabled
125 // or if the remapping has already been done by a prior call.
126 static bool remap_shared_readonly_as_readwrite() NOT_CDS_RETURN_(true);
127 static bool remapped_readwrite() {
128 CDS_ONLY(return _remapped_readwrite);
129 NOT_CDS(return false);
130 }
131
132 static bool try_link_class(JavaThread* current, InstanceKlass* ik);
133 static void link_shared_classes(TRAPS) NOT_CDS_RETURN;
134 static bool may_be_eagerly_linked(InstanceKlass* ik) NOT_CDS_RETURN_(false);
135
136 #if INCLUDE_CDS
137 // Alignment for the 2 core CDS regions (RW/RO) only.
138 // (Heap region alignments are decided by GC).
139 static size_t core_region_alignment();
140 static size_t protection_zone_size();
141 static void rewrite_nofast_bytecodes_and_calculate_fingerprints(Thread* thread, InstanceKlass* ik);
142 // print loaded classes names to file.
143 static void dump_loaded_classes(const char* file_name, TRAPS);
144 #endif
145
146 // Allocate a block of memory from the temporary "symbol" region.
147 static char* symbol_space_alloc(size_t num_bytes);
148
149 // This is the base address as specified by -XX:SharedBaseAddress during -Xshare:dump.
150 // Both the base/top archives are written using this as their base address.
151 //
152 // During static dump: _requested_base_address == SharedBaseAddress.
153 //
154 // During dynamic dump: _requested_base_address is not always the same as SharedBaseAddress:
155 // - SharedBaseAddress is used for *reading the base archive*. I.e., CompactHashtable uses
156 // it to convert offsets to pointers to Symbols in the base archive.
157 // The base archive may be mapped to an OS-selected address due to ASLR. E.g.,
158 // you may have SharedBaseAddress == 0x00ff123400000000.
159 // - _requested_base_address is used for *writing the output archive*. It's usually
160 // 0x800000000 (unless it was set by -XX:SharedBaseAddress during -Xshare:dump).
161 static char* requested_base_address() {
162 return _requested_base_address;
163 }
164
165 // Non-zero if the archive(s) need to be mapped a non-default location due to ASLR.
166 static intx relocation_delta() { return _relocation_delta; }
167
168 static bool use_windows_memory_mapping() {
169 const bool is_windows = (NOT_WINDOWS(false) WINDOWS_ONLY(true));
170 //const bool is_windows = true; // enable this to allow testing the windows mmap semantics on Linux, etc.
171 return is_windows;
172 }
173
174 // Can we skip some expensive operations related to modules?
175 static bool use_optimized_module_handling() { return NOT_CDS(false) CDS_ONLY(_use_optimized_module_handling); }
176 static void disable_optimized_module_handling() { _use_optimized_module_handling = false; }
177
178 private:
179 static void read_extra_data(JavaThread* current, const char* filename) NOT_CDS_RETURN;
180 static bool write_static_archive(ArchiveBuilder* builder, FileMapInfo* map_info, ArchiveHeapInfo* heap_info);
181 static FileMapInfo* open_static_archive();
182 static FileMapInfo* open_dynamic_archive();
183 // use_requested_addr: If true (default), attempt to map at the address the
184 static MapArchiveResult map_archives(FileMapInfo* static_mapinfo, FileMapInfo* dynamic_mapinfo,
185 bool use_requested_addr);
186 static char* reserve_address_space_for_archives(FileMapInfo* static_mapinfo,
187 FileMapInfo* dynamic_mapinfo,
188 bool use_archive_base_addr,
189 ReservedSpace& total_space_rs,
190 ReservedSpace& archive_space_rs,
191 ReservedSpace& class_space_rs);
192 static void release_reserved_spaces(ReservedSpace& total_space_rs,
193 ReservedSpace& archive_space_rs,
194 ReservedSpace& class_space_rs);
195 static MapArchiveResult map_archive(FileMapInfo* mapinfo, char* mapped_base_address, ReservedSpace rs);
196 static void unmap_archive(FileMapInfo* mapinfo);
197 static void get_default_classlist(char* default_classlist, const size_t buf_size);
198 };
199 #endif // SHARE_CDS_METASPACESHARED_HPP