1 /*
2 * Copyright (c) 2012, 2017, 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_VM_MEMORY_METASPACESHARED_HPP
26 #define SHARE_VM_MEMORY_METASPACESHARED_HPP
27
28 #include "classfile/compactHashtable.hpp"
29 #include "memory/allocation.hpp"
30 #include "memory/memRegion.hpp"
31 #include "memory/virtualspace.hpp"
32 #include "utilities/exceptions.hpp"
33 #include "utilities/macros.hpp"
34 #include "utilities/resourceHash.hpp"
35
36 #define MAX_SHARED_DELTA (0x7FFFFFFF)
37
38 class FileMapInfo;
39
40 class MetaspaceSharedStats VALUE_OBJ_CLASS_SPEC {
41 public:
42 MetaspaceSharedStats() {
43 memset(this, 0, sizeof(*this));
44 }
45 CompactHashtableStats symbol;
46 CompactHashtableStats string;
47 };
48
49 // Class Data Sharing Support
50 class MetaspaceShared : AllStatic {
51
52 // CDS support
53 static ReservedSpace _shared_rs;
54 static VirtualSpace _shared_vs;
55 static int _max_alignment;
56 static MetaspaceSharedStats _stats;
57 static bool _has_error_classes;
58 static bool _archive_loading_failed;
59 static bool _remapped_readwrite;
60 static bool _open_archive_heap_region_mapped;
61 static address _cds_i2i_entry_code_buffers;
62 static size_t _cds_i2i_entry_code_buffers_size;
63 static size_t _core_spaces_size;
64 public:
65 enum {
66 // core archive spaces
67 mc = 0, // miscellaneous code for method trampolines
68 rw = 1, // read-write shared space in the heap
69 ro = 2, // read-only shared space in the heap
70 md = 3, // miscellaneous data for initializing tables, etc.
71 num_core_spaces = 4, // number of non-string regions
72
73 // optional mapped spaces
74 // Currently it only contains class file data.
75 od = num_core_spaces,
76 num_non_heap_spaces = od + 1,
77
78 // mapped java heap regions
79 first_string = od + 1, // index of first string region
80 max_strings = 2, // max number of string regions in string space
81 first_open_archive_heap_region = first_string + max_strings,
82 max_open_archive_heap_region = 2,
83
84 last_valid_region = first_open_archive_heap_region + max_open_archive_heap_region - 1,
85 n_regions = last_valid_region + 1 // total number of regions
86 };
87
88 static void prepare_for_dumping() NOT_CDS_RETURN;
89 static void preload_and_dump(TRAPS) NOT_CDS_RETURN;
90 static int preload_classes(const char * class_list_path,
91 TRAPS) NOT_CDS_RETURN_(0);
92
93 #if INCLUDE_CDS_JAVA_HEAP
94 private:
95 static bool obj_equals(oop const& p1, oop const& p2) {
96 return p1 == p2;
97 }
98 static unsigned obj_hash(oop const& p) {
99 unsigned hash = (unsigned)((uintptr_t)&p);
100 return hash ^ (hash >> LogMinObjAlignment);
101 }
102 typedef ResourceHashtable<oop, oop,
103 MetaspaceShared::obj_hash, MetaspaceShared::obj_equals> ArchivedObjectCache;
104 static ArchivedObjectCache* _archive_object_cache;
105
106 public:
107 static ArchivedObjectCache* archive_object_cache() {
108 return _archive_object_cache;
109 }
110 static oop archive_heap_object(oop obj, Thread* THREAD);
111 static void archive_resolved_constants(Thread* THREAD);
112 #endif
113 static bool allow_archive_heap_object() {
114 CDS_JAVA_HEAP_ONLY(return (UseG1GC && UseCompressedOops && UseCompressedClassPointers);)
115 NOT_CDS_JAVA_HEAP(return false;)
116 }
117 static void create_archive_object_cache() {
118 CDS_JAVA_HEAP_ONLY(_archive_object_cache = new ArchivedObjectCache(););
119 }
120 static void fixup_mapped_heap_regions() NOT_CDS_JAVA_HEAP_RETURN;
121
122 static void dump_open_archive_heap_objects(GrowableArray<MemRegion> * open_archive) NOT_CDS_JAVA_HEAP_RETURN;
123 static void set_open_archive_heap_region_mapped() {
124 CDS_JAVA_HEAP_ONLY(_open_archive_heap_region_mapped = true);
125 NOT_CDS_JAVA_HEAP_RETURN;
126 }
127 static bool open_archive_heap_region_mapped() {
128 CDS_JAVA_HEAP_ONLY(return _open_archive_heap_region_mapped);
129 NOT_CDS_JAVA_HEAP_RETURN_(false);
130 }
131
132 static ReservedSpace* shared_rs() {
133 CDS_ONLY(return &_shared_rs);
134 NOT_CDS(return NULL);
135 }
136 static void commit_shared_space_to(char* newtop) NOT_CDS_RETURN;
137 static size_t core_spaces_size() {
138 return _core_spaces_size;
139 }
140 static void initialize_shared_rs() NOT_CDS_RETURN;
141
142 // Delta of this object from the bottom of the archive.
143 static uintx object_delta(void* obj) {
144 assert(DumpSharedSpaces, "supported only for dumping");
145 assert(shared_rs()->contains(obj), "must be");
146 address base_address = address(shared_rs()->base());
147 uintx delta = address(obj) - base_address;
148 return delta;
149 }
150
151 static void set_archive_loading_failed() {
152 _archive_loading_failed = true;
153 }
154 static bool map_shared_spaces(FileMapInfo* mapinfo) NOT_CDS_RETURN_(false);
155 static void initialize_shared_spaces() NOT_CDS_RETURN;
156
157 // Return true if given address is in the mapped shared space.
158 static bool is_in_shared_space(const void* p) NOT_CDS_RETURN_(false);
159
160 // Return true if given address is in the shared region corresponding to the idx
161 static bool is_in_shared_region(const void* p, int idx) NOT_CDS_RETURN_(false);
162
163 static bool is_heap_region(int idx) {
164 CDS_JAVA_HEAP_ONLY(return (idx >= MetaspaceShared::first_string &&
165 idx < MetaspaceShared::first_open_archive_heap_region +
166 MetaspaceShared::max_open_archive_heap_region));
167 NOT_CDS_JAVA_HEAP_RETURN_(false);
168 }
169 static bool is_string_region(int idx) {
170 CDS_JAVA_HEAP_ONLY(return (idx >= MetaspaceShared::first_string &&
171 idx < MetaspaceShared::first_string + MetaspaceShared::max_strings));
172 NOT_CDS_JAVA_HEAP_RETURN_(false);
173 }
174 static bool is_open_archive_heap_region(int idx) {
175 CDS_JAVA_HEAP_ONLY(return (idx >= MetaspaceShared::first_open_archive_heap_region &&
176 idx < MetaspaceShared::first_open_archive_heap_region +
177 MetaspaceShared::max_open_archive_heap_region));
178 NOT_CDS_JAVA_HEAP_RETURN_(false);
179 }
180 static bool is_in_trampoline_frame(address addr) NOT_CDS_RETURN_(false);
181
182 static void allocate_cpp_vtable_clones();
183 static intptr_t* clone_cpp_vtables(intptr_t* p);
184 static void zero_cpp_vtable_clones_for_writing();
185 static void patch_cpp_vtable_pointers();
186 static bool is_valid_shared_method(const Method* m) NOT_CDS_RETURN_(false);
187 static void serialize(SerializeClosure* sc);
188
189 static MetaspaceSharedStats* stats() {
190 return &_stats;
191 }
192
193 static void report_out_of_space(const char* name, size_t needed_bytes);
194
195 // JVM/TI RedefineClasses() support:
196 // Remap the shared readonly space to shared readwrite, private if
197 // sharing is enabled. Simply returns true if sharing is not enabled
198 // or if the remapping has already been done by a prior call.
199 static bool remap_shared_readonly_as_readwrite() NOT_CDS_RETURN_(true);
200 static bool remapped_readwrite() {
201 CDS_ONLY(return _remapped_readwrite);
202 NOT_CDS(return false);
203 }
204
205 static void print_shared_spaces();
206
207 static bool try_link_class(InstanceKlass* ik, TRAPS);
208 static void link_and_cleanup_shared_classes(TRAPS);
209 static void check_shared_class_loader_type(Klass* obj);
210
211 // Allocate a block of memory from the "mc", "ro", or "rw" regions.
212 static char* misc_code_space_alloc(size_t num_bytes);
213 static char* read_only_space_alloc(size_t num_bytes);
214
215 template <typename T>
216 static Array<T>* new_ro_array(int length) {
217 #if INCLUDE_CDS
218 size_t byte_size = Array<T>::byte_sizeof(length, sizeof(T));
219 Array<T>* array = (Array<T>*)read_only_space_alloc(byte_size);
220 array->initialize(length);
221 return array;
222 #else
223 return NULL;
224 #endif
225 }
226
227 static address cds_i2i_entry_code_buffers(size_t total_size);
228
229 static address cds_i2i_entry_code_buffers() {
230 return _cds_i2i_entry_code_buffers;
231 }
232 static size_t cds_i2i_entry_code_buffers_size() {
233 return _cds_i2i_entry_code_buffers_size;
234 }
235 static void relocate_klass_ptr(oop o);
236 };
237 #endif // SHARE_VM_MEMORY_METASPACESHARED_HPP