1 /*
2 * Copyright (c) 2018, 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_HEAPSHARED_HPP
26 #define SHARE_VM_MEMORY_HEAPSHARED_HPP
27
28 #include "classfile/compactHashtable.hpp"
29 #include "classfile/systemDictionary.hpp"
30 #include "memory/allocation.hpp"
31 #include "memory/universe.hpp"
32 #include "oops/objArrayKlass.hpp"
33 #include "oops/oop.hpp"
34 #include "oops/typeArrayKlass.hpp"
35 #include "utilities/bitMap.hpp"
36 #include "utilities/growableArray.hpp"
37 #include "utilities/resourceHash.hpp"
38
39 #if INCLUDE_CDS_JAVA_HEAP
40 // A dump time sub-graph info for Klass _k. It includes the entry points
41 // (static fields in _k's mirror) of the archived sub-graphs reachable
42 // from _k's mirror. It also contains a list of Klasses of the objects
43 // within the sub-graphs.
44 class KlassSubGraphInfo: public CHeapObj<mtClass> {
45 private:
46 // The class that contains the static field(s) as the entry point(s)
47 // of archived object sub-graph(s).
48 Klass* _k;
49 // A list of classes need to be loaded and initialized before the archived
50 // object sub-graphs can be accessed at runtime.
51 GrowableArray<Klass*>* _subgraph_object_klasses;
52 // A list of _k's static fields as the entry points of archived sub-graphs.
53 // For each entry field, it is a pair of field_offset and field_value.
54 GrowableArray<juint>* _subgraph_entry_fields;
55
56 public:
57 KlassSubGraphInfo(Klass* k) :
58 _k(k), _subgraph_object_klasses(NULL),
59 _subgraph_entry_fields(NULL) {}
60 ~KlassSubGraphInfo() {
61 if (_subgraph_object_klasses != NULL) {
62 delete _subgraph_object_klasses;
63 }
64 if (_subgraph_entry_fields != NULL) {
65 delete _subgraph_entry_fields;
66 }
67 };
68
69 Klass* klass() { return _k; }
70 GrowableArray<Klass*>* subgraph_object_klasses() {
71 return _subgraph_object_klasses;
72 }
73 GrowableArray<juint>* subgraph_entry_fields() {
74 return _subgraph_entry_fields;
75 }
76 void add_subgraph_entry_field(int static_field_offset, oop v);
77 void add_subgraph_object_klass(Klass *orig_k, Klass *relocated_k);
78 int num_subgraph_object_klasses() {
79 return _subgraph_object_klasses == NULL ? 0 :
80 _subgraph_object_klasses->length();
81 }
82 };
83
84 // An archived record of object sub-graphs reachable from static
85 // fields within _k's mirror. The record is reloaded from the archive
86 // at runtime.
87 class ArchivedKlassSubGraphInfoRecord {
88 private:
89 Klass* _k;
90
91 // contains pairs of field offset and value for each subgraph entry field
92 Array<juint>* _entry_field_records;
93
94 // klasses of objects in archived sub-graphs referenced from the entry points
95 // (static fields) in the containing class
96 Array<Klass*>* _subgraph_object_klasses;
97 public:
98 ArchivedKlassSubGraphInfoRecord() :
99 _k(NULL), _entry_field_records(NULL), _subgraph_object_klasses(NULL) {}
100 void init(KlassSubGraphInfo* info);
101 Klass* klass() { return _k; }
102 Array<juint>* entry_field_records() { return _entry_field_records; }
103 Array<Klass*>* subgraph_object_klasses() { return _subgraph_object_klasses; }
104 };
105 #endif // INCLUDE_CDS_JAVA_HEAP
106
107 class HeapShared: AllStatic {
108 friend class VerifySharedOopClosure;
109 private:
110 #if INCLUDE_CDS_JAVA_HEAP
111
112 static bool klass_equals(Klass* const& p1, Klass* const& p2) {
113 return primitive_equals<Klass*>(p1, p2);
114 }
115
116 static unsigned klass_hash(Klass* const& klass) {
117 return primitive_hash<address>((address)klass);
118 }
119
120 class DumpTimeKlassSubGraphInfoTable
121 : public ResourceHashtable<Klass*, KlassSubGraphInfo,
122 HeapShared::klass_hash,
123 HeapShared::klass_equals,
124 137, // prime number
125 ResourceObj::C_HEAP> {
126 public:
127 int _count;
128 };
129
130 inline static ArchivedKlassSubGraphInfoRecord* read_record_from_compact_hashtable(address base_address, u4 offset) {
131 return (ArchivedKlassSubGraphInfoRecord*)(base_address + offset);
132 }
133
134 inline static bool record_equals_compact_hashtable_entry(ArchivedKlassSubGraphInfoRecord* value, const Klass* key, int len_unused) {
135 return (value->klass() == key);
136 }
137
138 typedef CompactHashtable<
139 const Klass*,
140 ArchivedKlassSubGraphInfoRecord*,
141 read_record_from_compact_hashtable,
142 record_equals_compact_hashtable_entry
143 > RunTimeKlassSubGraphInfoTable;
144
145 static DumpTimeKlassSubGraphInfoTable* _dump_time_subgraph_info_table;
146 static RunTimeKlassSubGraphInfoTable _run_time_subgraph_info_table;
147
148 // Archive object sub-graph starting from the given static field
149 // in Klass k's mirror.
150 static void archive_reachable_objects_from_static_field(
151 InstanceKlass* k, const char* klass_name,
152 int field_offset, const char* field_name, TRAPS);
153 static void verify_subgraph_from_static_field(
154 InstanceKlass* k, int field_offset) PRODUCT_RETURN;
155
156 static void verify_reachable_objects_from(oop obj, bool is_archived) PRODUCT_RETURN;
157
158 static KlassSubGraphInfo* get_subgraph_info(Klass *k);
159 static int num_of_subgraph_infos();
160
161 static void build_archived_subgraph_info_records(int num_records);
162
163 // Used by decode_from_archive
164 static address _narrow_oop_base;
165 static int _narrow_oop_shift;
166
167 static bool oop_equals(oop const& p1, oop const& p2) {
168 return primitive_equals<oop>(p1, p2);
169 }
170
171 static unsigned oop_hash(oop const& p) {
172 return primitive_hash<address>((address)p);
173 }
174
175 typedef ResourceHashtable<oop, bool,
176 HeapShared::oop_hash,
177 HeapShared::oop_equals,
178 15889, // prime number
179 ResourceObj::C_HEAP> SeenObjectsTable;
180
181 static SeenObjectsTable *_seen_objects_table;
182
183 static void init_seen_objects_table() {
184 assert(_seen_objects_table == NULL, "must be");
185 _seen_objects_table = new (ResourceObj::C_HEAP, mtClass)SeenObjectsTable();
186 }
187 static void delete_seen_objects_table() {
188 assert(_seen_objects_table != NULL, "must be");
189 delete _seen_objects_table;
190 _seen_objects_table = NULL;
191 }
192
193 // Statistics (for one round of start_recording_subgraph ... done_recording_subgraph)
194 static int _num_new_walked_objs;
195 static int _num_new_archived_objs;
196 static int _num_old_recorded_klasses;
197
198 // Statistics (for all archived subgraphs)
199 static int _num_total_subgraph_recordings;
200 static int _num_total_walked_objs;
201 static int _num_total_archived_objs;
202 static int _num_total_recorded_klasses;
203 static int _num_total_verifications;
204
205 static void start_recording_subgraph(InstanceKlass *k, const char* klass_name);
206 static void done_recording_subgraph(InstanceKlass *k, const char* klass_name);
207
208 static bool has_been_seen_during_subgraph_recording(oop obj);
209 static void set_has_been_seen_during_subgraph_recording(oop obj);
210 #endif // INCLUDE_CDS_JAVA_HEAP
211 public:
212 static char* read_archived_subgraph_infos(char* buffer) NOT_CDS_JAVA_HEAP_RETURN_(buffer);
213 static void write_archived_subgraph_infos() NOT_CDS_JAVA_HEAP_RETURN;
214 static void initialize_from_archived_subgraph(Klass* k) NOT_CDS_JAVA_HEAP_RETURN;
215
216 // NarrowOops stored in the CDS archive may use a different encoding scheme
217 // than Universe::narrow_oop_{base,shift} -- see FileMapInfo::map_heap_regions_impl.
218 // To decode them, do not use CompressedOops::decode_not_null. Use this
219 // function instead.
220 inline static oop decode_from_archive(narrowOop v) NOT_CDS_JAVA_HEAP_RETURN_(NULL);
221
222 static void init_narrow_oop_decoding(address base, int shift) NOT_CDS_JAVA_HEAP_RETURN;
223
224 static void patch_archived_heap_embedded_pointers(MemRegion mem, address oopmap,
225 size_t oopmap_in_bits) NOT_CDS_JAVA_HEAP_RETURN;
226
227 static void init_archivable_static_fields(Thread* THREAD) NOT_CDS_JAVA_HEAP_RETURN;
228 static void archive_static_fields(Thread* THREAD) NOT_CDS_JAVA_HEAP_RETURN;
229 static void write_subgraph_info_table() NOT_CDS_JAVA_HEAP_RETURN;
230 static void serialize_subgraph_info_table_header(SerializeClosure* soc) NOT_CDS_JAVA_HEAP_RETURN;
231
232 #if INCLUDE_CDS_JAVA_HEAP
233 static ResourceBitMap calculate_oopmap(MemRegion region);
234 static oop archive_reachable_objects_from(int level, KlassSubGraphInfo* subgraph_info, oop orig_obj, TRAPS);
235 static void verify_subgraph_from(oop orig_obj) PRODUCT_RETURN;
236 #endif
237 };
238 #endif // SHARE_VM_MEMORY_HEAPSHARED_HPP