1 /*
2 * Copyright (c) 2012, 2019, 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_MEMORY_METASPACESHARED_HPP
26 #define SHARE_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 "oops/oop.hpp"
33 #include "utilities/exceptions.hpp"
34 #include "utilities/macros.hpp"
35 #include "utilities/resourceHash.hpp"
36
37 #define MAX_SHARED_DELTA (0x7FFFFFFF)
38
39 class FileMapInfo;
40
41 class MetaspaceSharedStats {
42 public:
43 MetaspaceSharedStats() {
44 memset(this, 0, sizeof(*this));
45 }
46 CompactHashtableStats symbol;
47 CompactHashtableStats string;
48 };
49
50 // Class Data Sharing Support
51 class MetaspaceShared : AllStatic {
52
53 // CDS support
54 static ReservedSpace _shared_rs;
55 static VirtualSpace _shared_vs;
56 static int _max_alignment;
57 static MetaspaceSharedStats _stats;
58 static bool _has_error_classes;
59 static bool _archive_loading_failed;
60 static bool _remapped_readwrite;
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 num_non_heap_spaces = 4,
73
74 // mapped java heap regions
75 first_closed_archive_heap_region = md + 1,
76 max_closed_archive_heap_region = 2,
77 last_closed_archive_heap_region = first_closed_archive_heap_region + max_closed_archive_heap_region - 1,
78 first_open_archive_heap_region = last_closed_archive_heap_region + 1,
79 max_open_archive_heap_region = 2,
80 last_open_archive_heap_region = first_open_archive_heap_region + max_open_archive_heap_region - 1,
81
82 last_valid_region = last_open_archive_heap_region,
83 n_regions = last_valid_region + 1 // total number of regions
84 };
85
86 static void prepare_for_dumping() NOT_CDS_RETURN;
87 static void preload_and_dump(TRAPS) NOT_CDS_RETURN;
88 static int preload_classes(const char * class_list_path,
89 TRAPS) NOT_CDS_RETURN_(0);
90
91 static GrowableArray<Klass*>* collected_klasses();
92
93 static ReservedSpace* shared_rs() {
94 CDS_ONLY(return &_shared_rs);
95 NOT_CDS(return NULL);
96 }
97 static void commit_shared_space_to(char* newtop) NOT_CDS_RETURN;
98 static size_t core_spaces_size() {
99 assert(DumpSharedSpaces || UseSharedSpaces, "sanity");
100 assert(_core_spaces_size != 0, "sanity");
101 return _core_spaces_size;
102 }
103 static void initialize_dumptime_shared_and_meta_spaces() NOT_CDS_RETURN;
104 static void initialize_runtime_shared_and_meta_spaces() NOT_CDS_RETURN;
105 static void post_initialize(TRAPS) NOT_CDS_RETURN;
106
107 // Delta of this object from the bottom of the archive.
108 static uintx object_delta_uintx(void* obj) {
109 assert(DumpSharedSpaces, "supported only for dumping");
110 assert(shared_rs()->contains(obj), "must be");
111 address base_address = address(shared_rs()->base());
112 uintx deltax = address(obj) - base_address;
113 return deltax;
114 }
115
116 static u4 object_delta_u4(void* obj) {
117 // offset is guaranteed to be less than MAX_SHARED_DELTA in DumpRegion::expand_top_to()
118 uintx deltax = object_delta_uintx(obj);
119 guarantee(deltax <= MAX_SHARED_DELTA, "must be 32-bit offset");
120 return (u4)deltax;
121 }
122
123 static void set_archive_loading_failed() {
124 _archive_loading_failed = true;
125 }
126 static bool map_shared_spaces(FileMapInfo* mapinfo) NOT_CDS_RETURN_(false);
127 static void initialize_shared_spaces() NOT_CDS_RETURN;
128
129 // Return true if given address is in the shared metaspace regions (i.e., excluding any
130 // mapped shared heap regions.)
131 static bool is_in_shared_metaspace(const void* p) {
132 // If no shared metaspace regions are mapped, MetaspceObj::_shared_metaspace_{base,top} will
133 // both be NULL and all values of p will be rejected quickly.
134 return (p < MetaspaceObj::shared_metaspace_top() && p >= MetaspaceObj::shared_metaspace_base());
135 }
136
137 // Return true if given address is in the shared region corresponding to the idx
138 static bool is_in_shared_region(const void* p, int idx) NOT_CDS_RETURN_(false);
139
140 static bool is_in_trampoline_frame(address addr) NOT_CDS_RETURN_(false);
141
142 static void allocate_cpp_vtable_clones();
143 static intptr_t* clone_cpp_vtables(intptr_t* p);
144 static void zero_cpp_vtable_clones_for_writing();
145 static void patch_cpp_vtable_pointers();
146 static bool is_valid_shared_method(const Method* m) NOT_CDS_RETURN_(false);
147 static void serialize(SerializeClosure* sc) NOT_CDS_RETURN;
148
149 static MetaspaceSharedStats* stats() {
150 return &_stats;
151 }
152
153 static void report_out_of_space(const char* name, size_t needed_bytes);
154
155 // JVM/TI RedefineClasses() support:
156 // Remap the shared readonly space to shared readwrite, private if
157 // sharing is enabled. Simply returns true if sharing is not enabled
158 // or if the remapping has already been done by a prior call.
159 static bool remap_shared_readonly_as_readwrite() NOT_CDS_RETURN_(true);
160 static bool remapped_readwrite() {
161 CDS_ONLY(return _remapped_readwrite);
162 NOT_CDS(return false);
163 }
164
165 static bool try_link_class(InstanceKlass* ik, TRAPS);
166 static void link_and_cleanup_shared_classes(TRAPS);
167
168 // Allocate a block of memory from the "mc", "ro", or "rw" regions.
169 static char* misc_code_space_alloc(size_t num_bytes);
170 static char* read_only_space_alloc(size_t num_bytes);
171
172 template <typename T>
173 static Array<T>* new_ro_array(int length) {
174 #if INCLUDE_CDS
175 size_t byte_size = Array<T>::byte_sizeof(length, sizeof(T));
176 Array<T>* array = (Array<T>*)read_only_space_alloc(byte_size);
177 array->initialize(length);
178 return array;
179 #else
180 return NULL;
181 #endif
182 }
183
184 static address cds_i2i_entry_code_buffers(size_t total_size);
185
186 static address cds_i2i_entry_code_buffers() {
187 return _cds_i2i_entry_code_buffers;
188 }
189 static size_t cds_i2i_entry_code_buffers_size() {
190 return _cds_i2i_entry_code_buffers_size;
191 }
192 static void relocate_klass_ptr(oop o);
193
194 static Klass* get_relocated_klass(Klass *k);
195
196 private:
197 static void read_extra_data(const char* filename, TRAPS) NOT_CDS_RETURN;
198 };
199 #endif // SHARE_MEMORY_METASPACESHARED_HPP