1 /*
2 * Copyright (c) 2003, 2010, 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 #include "precompiled.hpp"
26 #include "classfile/symbolTable.hpp"
27 #include "classfile/systemDictionary.hpp"
28 #include "memory/filemap.hpp"
29 #include "oops/oop.inline.hpp"
30 #include "utilities/hashtable.inline.hpp"
31
32
33 // Closure for serializing initialization data in from a data area
34 // (oop_array) read from the shared file.
35
36 class ReadClosure : public SerializeOopClosure {
37 private:
38 oop** _oop_array;
39
40 inline oop nextOop() {
41 return *(*_oop_array)++;
42 }
43
44 public:
45 ReadClosure(oop** oop_array) { _oop_array = oop_array; }
46
47 void do_oop(oop* p) {
48 assert(SharedSkipVerify || *p == NULL || *p == Universe::klassKlassObj(),
49 "initializing previously initialized oop.");
50 oop obj = nextOop();
51 assert(SharedSkipVerify || (intptr_t)obj >= 0 || (intptr_t)obj < -100,
52 "hit tag while initializing oops.");
53 assert(SharedSkipVerify || obj->is_oop_or_null(), "invalid oop");
54 *p = obj;
55 }
56
57 void do_oop(narrowOop* p) { ShouldNotReachHere(); }
58
59 void do_ptr(void** p) {
60 assert(*p == NULL, "initializing previous initialized pointer.");
61 void* obj = nextOop();
62 assert((intptr_t)obj >= 0 || (intptr_t)obj < -100,
63 "hit tag while initializing ptrs.");
64 *p = obj;
65 }
66
67 void do_ptr(HeapWord** p) { do_ptr((void **) p); }
68
69 void do_int(int* p) {
70 *p = (int)(intptr_t)nextOop();
71 }
72
73 void do_size_t(size_t* p) {
74 // Assumes that size_t and pointers are the same size.
75 *p = (size_t)nextOop();
76 }
77
78 void do_tag(int tag) {
79 int old_tag;
80 do_int(&old_tag);
81 FileMapInfo::assert_mark(tag == old_tag);
82 }
83
84 void do_region(u_char* start, size_t size) {
85 assert((intptr_t)start % sizeof(oop) == 0, "bad alignment");
86 assert(size % sizeof(oop) == 0, "bad size");
87 do_tag((int)size);
88 while (size > 0) {
89 *(oop*)start = nextOop();
90 start += sizeof(oop);
91 size -= sizeof(oop);
92 }
93 }
94
95 bool reading() const { return true; }
96 };
97
98
99 // Read the oop and miscellaneous data from the shared file, and
100 // serialize it out to its various destinations.
101
102 void CompactingPermGenGen::initialize_oops() {
103 FileMapInfo *mapinfo = FileMapInfo::current_info();
104
105 char* buffer = mapinfo->region_base(md);
106
107 // Skip over (reserve space for) a list of addresses of C++ vtables
108 // for Klass objects. They get filled in later.
109
110 // Skip over (reserve space for) dummy C++ vtables Klass objects.
111 // They are used as is.
112
113 void** vtbl_list = (void**)buffer;
114 buffer += vtbl_list_size * sizeof(void*);
115 intptr_t vtable_size = *(intptr_t*)buffer;
116 buffer += sizeof(intptr_t);
117 buffer += vtable_size;
118
119 // Create the symbol table using the bucket array at this spot in the
120 // misc data space. Since the symbol table is often modified, this
121 // region (of mapped pages) will be copy-on-write.
122
123 int symbolTableLen = *(intptr_t*)buffer;
124 buffer += sizeof(intptr_t);
125 int number_of_entries = *(intptr_t*)buffer;
126 buffer += sizeof(intptr_t);
127 SymbolTable::create_table((HashtableBucket*)buffer, symbolTableLen,
128 number_of_entries);
129 buffer += symbolTableLen;
130
131 // Create the string table using the bucket array at this spot in the
132 // misc data space. Since the string table is often modified, this
133 // region (of mapped pages) will be copy-on-write.
134
135 int stringTableLen = *(intptr_t*)buffer;
136 buffer += sizeof(intptr_t);
137 number_of_entries = *(intptr_t*)buffer;
138 buffer += sizeof(intptr_t);
139 StringTable::create_table((HashtableBucket*)buffer, stringTableLen,
140 number_of_entries);
141 buffer += stringTableLen;
142
143 // Create the shared dictionary using the bucket array at this spot in
144 // the misc data space. Since the shared dictionary table is never
145 // modified, this region (of mapped pages) will be (effectively, if
146 // not explicitly) read-only.
147
148 int sharedDictionaryLen = *(intptr_t*)buffer;
149 buffer += sizeof(intptr_t);
150 number_of_entries = *(intptr_t*)buffer;
151 buffer += sizeof(intptr_t);
152 SystemDictionary::set_shared_dictionary((HashtableBucket*)buffer,
153 sharedDictionaryLen,
154 number_of_entries);
155 buffer += sharedDictionaryLen;
156
157 // Create the package info table using the bucket array at this spot in
158 // the misc data space. Since the package info table is never
159 // modified, this region (of mapped pages) will be (effectively, if
160 // not explicitly) read-only.
161
162 int pkgInfoLen = *(intptr_t*)buffer;
163 buffer += sizeof(intptr_t);
164 number_of_entries = *(intptr_t*)buffer;
165 buffer += sizeof(intptr_t);
166 ClassLoader::create_package_info_table((HashtableBucket*)buffer, pkgInfoLen,
167 number_of_entries);
168 buffer += pkgInfoLen;
169 ClassLoader::verify();
170
171 // The following data in the shared misc data region are the linked
172 // list elements (HashtableEntry objects) for the symbol table, string
173 // table, and shared dictionary. The heap objects refered to by the
174 // symbol table, string table, and shared dictionary are permanent and
175 // unmovable. Since new entries added to the string and symbol tables
176 // are always added at the beginning of the linked lists, THESE LINKED
177 // LIST ELEMENTS ARE READ-ONLY.
178
179 int len = *(intptr_t*)buffer; // skip over symbol table entries
180 buffer += sizeof(intptr_t);
181 buffer += len;
182
183 len = *(intptr_t*)buffer; // skip over string table entries
184 buffer += sizeof(intptr_t);
185 buffer += len;
186
187 len = *(intptr_t*)buffer; // skip over shared dictionary entries
188 buffer += sizeof(intptr_t);
189 buffer += len;
190
191 len = *(intptr_t*)buffer; // skip over package info table entries
192 buffer += sizeof(intptr_t);
193 buffer += len;
194
195 len = *(intptr_t*)buffer; // skip over package info table char[] arrays.
196 buffer += sizeof(intptr_t);
197 buffer += len;
198
199 oop* oop_array = (oop*)buffer;
200 ReadClosure rc(&oop_array);
201 serialize_oops(&rc);
202 }