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