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
35 #define MAX_SHARED_DELTA (0x7FFFFFFF)
36
37 class FileMapInfo;
38
39 class MetaspaceSharedStats VALUE_OBJ_CLASS_SPEC {
40 public:
41 MetaspaceSharedStats() {
42 memset(this, 0, sizeof(*this));
43 }
44 CompactHashtableStats symbol;
45 CompactHashtableStats string;
46 };
47
48 // Class Data Sharing Support
49 class MetaspaceShared : AllStatic {
50
51 // CDS support
52 static ReservedSpace _shared_rs;
53 static VirtualSpace _shared_vs;
54 static int _max_alignment;
55 static MetaspaceSharedStats _stats;
56 static bool _has_error_classes;
57 static bool _archive_loading_failed;
58 static bool _remapped_readwrite;
59 static address _cds_i2i_entry_code_buffers;
60 static size_t _cds_i2i_entry_code_buffers_size;
61 static size_t _core_spaces_size;
62 public:
63 enum {
64 mc = 0, // miscellaneous code for method trampolines
65 rw = 1, // read-write shared space in the heap
66 ro = 2, // read-only shared space in the heap
67 md = 3, // miscellaneous data for initializing tables, etc.
68 max_strings = 2, // max number of string regions in string space
69 num_non_strings = 4, // number of non-string regions
70 first_string = num_non_strings, // index of first string region
71 // The optional data region is the last region.
72 // Currently it only contains class file data.
73 od = max_strings + num_non_strings,
74 last_valid_region = od,
75 n_regions = od + 1 // total number of regions
76 };
77
78 static void prepare_for_dumping() NOT_CDS_RETURN;
79 static void preload_and_dump(TRAPS) NOT_CDS_RETURN;
80 static int preload_classes(const char * class_list_path,
81 TRAPS) NOT_CDS_RETURN_(0);
82
83 static ReservedSpace* shared_rs() {
84 CDS_ONLY(return &_shared_rs);
85 NOT_CDS(return NULL);
86 }
87 static void commit_shared_space_to(char* newtop) NOT_CDS_RETURN;
88 static size_t core_spaces_size() {
89 return _core_spaces_size;
90 }
91 static void initialize_shared_rs() NOT_CDS_RETURN;
92
93 // Delta of this object from the bottom of the archive.
94 static uintx object_delta(void* obj) {
95 assert(DumpSharedSpaces, "supported only for dumping");
96 assert(shared_rs()->contains(obj), "must be");
97 address base_address = address(shared_rs()->base());
98 uintx delta = address(obj) - base_address;
99 return delta;
100 }
101
102 static void set_archive_loading_failed() {
103 _archive_loading_failed = true;
104 }
105 static bool map_shared_spaces(FileMapInfo* mapinfo) NOT_CDS_RETURN_(false);
106 static void initialize_shared_spaces() NOT_CDS_RETURN;
107 static void fixup_shared_string_regions() NOT_CDS_RETURN;
108
109 // Return true if given address is in the mapped shared space.
110 static bool is_in_shared_space(const void* p) NOT_CDS_RETURN_(false);
111
112 // Return true if given address is in the shared region corresponding to the idx
113 static bool is_in_shared_region(const void* p, int idx) NOT_CDS_RETURN_(false);
114
115 static bool is_in_trampoline_frame(address addr) NOT_CDS_RETURN_(false);
116 static bool is_string_region(int idx) NOT_CDS_RETURN_(false);
117
118 static void allocate_cpp_vtable_clones();
119 static intptr_t* clone_cpp_vtables(intptr_t* p);
120 static void zero_cpp_vtable_clones_for_writing();
121 static void patch_cpp_vtable_pointers();
122 static bool is_valid_shared_method(const Method* m) NOT_CDS_RETURN_(false);
123 static void serialize(SerializeClosure* sc);
124
125
126 static MetaspaceSharedStats* stats() {
127 return &_stats;
128 }
129
130 static void report_out_of_space(const char* name, size_t needed_bytes);
131
132 // JVM/TI RedefineClasses() support:
133 // Remap the shared readonly space to shared readwrite, private if
134 // sharing is enabled. Simply returns true if sharing is not enabled
135 // or if the remapping has already been done by a prior call.
136 static bool remap_shared_readonly_as_readwrite() NOT_CDS_RETURN_(true);
137 static bool remapped_readwrite() {
138 CDS_ONLY(return _remapped_readwrite);
139 NOT_CDS(return false);
140 }
141
142 static void print_shared_spaces();
143
144 static bool try_link_class(InstanceKlass* ik, TRAPS);
145 static void link_and_cleanup_shared_classes(TRAPS);
146 static void check_shared_class_loader_type(Klass* obj);
147
148 // Allocate a block of memory from the "mc", "ro", or "rw" regions.
149 static char* misc_code_space_alloc(size_t num_bytes);
150 static char* read_only_space_alloc(size_t num_bytes);
151
152 template <typename T>
153 static Array<T>* new_ro_array(int length) {
154 #if INCLUDE_CDS
155 size_t byte_size = Array<T>::byte_sizeof(length, sizeof(T));
156 Array<T>* array = (Array<T>*)read_only_space_alloc(byte_size);
157 array->initialize(length);
158 return array;
159 #else
160 return NULL;
161 #endif
162 }
163
164 static address cds_i2i_entry_code_buffers(size_t total_size);
165
166 static address cds_i2i_entry_code_buffers() {
167 return _cds_i2i_entry_code_buffers;
168 }
169 static size_t cds_i2i_entry_code_buffers_size() {
170 return _cds_i2i_entry_code_buffers_size;
171 }
172 static void relocate_klass_ptr(oop o);
173 };
174 #endif // SHARE_VM_MEMORY_METASPACESHARED_HPP