1 /*
2 * Copyright (c) 2018, 2020, 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_HEAPSHARED_HPP
26 #define SHARE_MEMORY_HEAPSHARED_HPP
27
28 #include "classfile/compactHashtable.hpp"
29 #include "classfile/systemDictionary.hpp"
30 #include "memory/allocation.hpp"
31 #include "memory/metaspaceShared.hpp"
32 #include "oops/compressedOops.hpp"
33 #include "oops/objArrayKlass.hpp"
34 #include "oops/oop.hpp"
35 #include "oops/typeArrayKlass.hpp"
36 #include "utilities/bitMap.hpp"
37 #include "utilities/growableArray.hpp"
38 #include "utilities/resourceHash.hpp"
39
40 #if INCLUDE_CDS_JAVA_HEAP
41 struct ArchivableStaticFieldInfo {
42 const char* klass_name;
43 const char* field_name;
44 InstanceKlass* klass;
45 int offset;
46 BasicType type;
47 };
48
49 // A dump time sub-graph info for Klass _k. It includes the entry points
50 // (static fields in _k's mirror) of the archived sub-graphs reachable
51 // from _k's mirror. It also contains a list of Klasses of the objects
52 // within the sub-graphs.
53 class KlassSubGraphInfo: public CHeapObj<mtClass> {
54 private:
55 // The class that contains the static field(s) as the entry point(s)
56 // of archived object sub-graph(s).
57 Klass* _k;
58 // A list of classes need to be loaded and initialized before the archived
59 // object sub-graphs can be accessed at runtime.
60 GrowableArray<Klass*>* _subgraph_object_klasses;
61 // A list of _k's static fields as the entry points of archived sub-graphs.
62 // For each entry field, it is a tuple of field_offset, field_value and
63 // is_closed_archive flag.
64 GrowableArray<juint>* _subgraph_entry_fields;
65
66 public:
67 KlassSubGraphInfo(Klass* k) :
68 _k(k), _subgraph_object_klasses(NULL),
69 _subgraph_entry_fields(NULL) {}
70 ~KlassSubGraphInfo() {
71 if (_subgraph_object_klasses != NULL) {
72 delete _subgraph_object_klasses;
73 }
74 if (_subgraph_entry_fields != NULL) {
75 delete _subgraph_entry_fields;
76 }
77 };
78
79 Klass* klass() { return _k; }
80 GrowableArray<Klass*>* subgraph_object_klasses() {
81 return _subgraph_object_klasses;
82 }
83 GrowableArray<juint>* subgraph_entry_fields() {
84 return _subgraph_entry_fields;
85 }
86 void add_subgraph_entry_field(int static_field_offset, oop v,
87 bool is_closed_archive);
88 void add_subgraph_object_klass(Klass *orig_k, Klass *relocated_k);
89 int num_subgraph_object_klasses() {
90 return _subgraph_object_klasses == NULL ? 0 :
91 _subgraph_object_klasses->length();
92 }
93 };
94
95 // An archived record of object sub-graphs reachable from static
96 // fields within _k's mirror. The record is reloaded from the archive
97 // at runtime.
98 class ArchivedKlassSubGraphInfoRecord {
99 private:
100 Klass* _k;
101
102 // contains pairs of field offset and value for each subgraph entry field
103 Array<juint>* _entry_field_records;
104
105 // klasses of objects in archived sub-graphs referenced from the entry points
106 // (static fields) in the containing class
107 Array<Klass*>* _subgraph_object_klasses;
108 public:
109 ArchivedKlassSubGraphInfoRecord() :
110 _k(NULL), _entry_field_records(NULL), _subgraph_object_klasses(NULL) {}
111 void init(KlassSubGraphInfo* info);
112 Klass* klass() const { return _k; }
113 Array<juint>* entry_field_records() const { return _entry_field_records; }
114 Array<Klass*>* subgraph_object_klasses() const { return _subgraph_object_klasses; }
115 };
116 #endif // INCLUDE_CDS_JAVA_HEAP
117
118 class HeapShared: AllStatic {
119 friend class VerifySharedOopClosure;
120 private:
121
122 #if INCLUDE_CDS_JAVA_HEAP
123 static bool _closed_archive_heap_region_mapped;
124 static bool _open_archive_heap_region_mapped;
125 static bool _archive_heap_region_fixed;
126
127 static bool oop_equals(oop const& p1, oop const& p2) {
128 return p1 == p2;
129 }
130 static unsigned oop_hash(oop const& p);
131
132 typedef ResourceHashtable<oop, oop,
133 HeapShared::oop_hash,
134 HeapShared::oop_equals,
135 15889, // prime number
136 ResourceObj::C_HEAP> ArchivedObjectCache;
137 static ArchivedObjectCache* _archived_object_cache;
138
139 static bool klass_equals(Klass* const& p1, Klass* const& p2) {
140 return primitive_equals<Klass*>(p1, p2);
141 }
142
143 static unsigned klass_hash(Klass* const& klass) {
144 // Generate deterministic hashcode even if SharedBaseAddress is changed due to ASLR.
145 return primitive_hash<address>(address(klass) - SharedBaseAddress);
146 }
147
148 class DumpTimeKlassSubGraphInfoTable
149 : public ResourceHashtable<Klass*, KlassSubGraphInfo,
150 HeapShared::klass_hash,
151 HeapShared::klass_equals,
152 137, // prime number
153 ResourceObj::C_HEAP> {
154 public:
155 int _count;
156 };
157
158 public: // solaris compiler wants this for RunTimeKlassSubGraphInfoTable
159 inline static bool record_equals_compact_hashtable_entry(
160 const ArchivedKlassSubGraphInfoRecord* value, const Klass* key, int len_unused) {
161 return (value->klass() == key);
162 }
163
164 private:
165 typedef OffsetCompactHashtable<
166 const Klass*,
167 const ArchivedKlassSubGraphInfoRecord*,
168 record_equals_compact_hashtable_entry
169 > RunTimeKlassSubGraphInfoTable;
170
171 static DumpTimeKlassSubGraphInfoTable* _dump_time_subgraph_info_table;
172 static RunTimeKlassSubGraphInfoTable _run_time_subgraph_info_table;
173
174 static void check_closed_archive_heap_region_object(InstanceKlass* k,
175 Thread* THREAD);
176
177 static void archive_object_subgraphs(ArchivableStaticFieldInfo fields[],
178 int num,
179 bool is_closed_archive,
180 Thread* THREAD);
181
182 // Archive object sub-graph starting from the given static field
183 // in Klass k's mirror.
184 static void archive_reachable_objects_from_static_field(
185 InstanceKlass* k, const char* klass_name,
186 int field_offset, const char* field_name,
187 bool is_closed_archive, TRAPS);
188
189 static void verify_subgraph_from_static_field(
190 InstanceKlass* k, int field_offset) PRODUCT_RETURN;
191 static void verify_reachable_objects_from(oop obj, bool is_archived) PRODUCT_RETURN;
192 static void verify_subgraph_from(oop orig_obj) PRODUCT_RETURN;
193
194 static KlassSubGraphInfo* get_subgraph_info(Klass *k);
195
196 static void init_subgraph_entry_fields(ArchivableStaticFieldInfo fields[],
197 int num, Thread* THREAD);
198
199 // Used by decode_from_archive
200 static address _narrow_oop_base;
201 static int _narrow_oop_shift;
202
203 typedef ResourceHashtable<oop, bool,
204 HeapShared::oop_hash,
205 HeapShared::oop_equals,
206 15889, // prime number
207 ResourceObj::C_HEAP> SeenObjectsTable;
208
209 static SeenObjectsTable *_seen_objects_table;
210
211 static void init_seen_objects_table() {
212 assert(_seen_objects_table == NULL, "must be");
213 _seen_objects_table = new (ResourceObj::C_HEAP, mtClass)SeenObjectsTable();
214 }
215 static void delete_seen_objects_table() {
216 assert(_seen_objects_table != NULL, "must be");
217 delete _seen_objects_table;
218 _seen_objects_table = NULL;
219 }
220
221 // Statistics (for one round of start_recording_subgraph ... done_recording_subgraph)
222 static int _num_new_walked_objs;
223 static int _num_new_archived_objs;
224 static int _num_old_recorded_klasses;
225
226 // Statistics (for all archived subgraphs)
227 static int _num_total_subgraph_recordings;
228 static int _num_total_walked_objs;
229 static int _num_total_archived_objs;
230 static int _num_total_recorded_klasses;
231 static int _num_total_verifications;
232
233 static void start_recording_subgraph(InstanceKlass *k, const char* klass_name);
234 static void done_recording_subgraph(InstanceKlass *k, const char* klass_name);
235
236 static bool has_been_seen_during_subgraph_recording(oop obj);
237 static void set_has_been_seen_during_subgraph_recording(oop obj);
238
239 public:
240 static void create_archived_object_cache() {
241 _archived_object_cache =
242 new (ResourceObj::C_HEAP, mtClass)ArchivedObjectCache();
243 }
244 static void destroy_archived_object_cache() {
245 delete _archived_object_cache;
246 _archived_object_cache = NULL;
247 }
248 static ArchivedObjectCache* archived_object_cache() {
249 return _archived_object_cache;
250 }
251
252 static oop find_archived_heap_object(oop obj);
253 static oop archive_heap_object(oop obj, Thread* THREAD);
254 static oop materialize_archived_object(narrowOop v);
255
256 static void archive_klass_objects(Thread* THREAD);
257
258 static void set_archive_heap_region_fixed() {
259 _archive_heap_region_fixed = true;
260 }
261 static bool archive_heap_region_fixed() {
262 return _archive_heap_region_fixed;
263 }
264
265 static void archive_java_heap_objects(GrowableArray<MemRegion> *closed,
266 GrowableArray<MemRegion> *open);
267 static void copy_closed_archive_heap_objects(GrowableArray<MemRegion> * closed_archive);
268 static void copy_open_archive_heap_objects(GrowableArray<MemRegion> * open_archive);
269
270 static oop archive_reachable_objects_from(int level,
271 KlassSubGraphInfo* subgraph_info,
272 oop orig_obj,
273 bool is_closed_archive,
274 TRAPS);
275
276 static ResourceBitMap calculate_oopmap(MemRegion region);
277 #endif // INCLUDE_CDS_JAVA_HEAP
278
279 public:
280 static void run_full_gc_in_vm_thread() NOT_CDS_JAVA_HEAP_RETURN;
281
282 static bool is_heap_object_archiving_allowed() {
283 CDS_JAVA_HEAP_ONLY(return (UseG1GC && UseCompressedOops && UseCompressedClassPointers);)
284 NOT_CDS_JAVA_HEAP(return false;)
285 }
286
287 static bool is_heap_region(int idx) {
288 CDS_JAVA_HEAP_ONLY(return (idx >= MetaspaceShared::first_closed_archive_heap_region &&
289 idx <= MetaspaceShared::last_open_archive_heap_region));
290 NOT_CDS_JAVA_HEAP_RETURN_(false);
291 }
292
293 static void set_closed_archive_heap_region_mapped() {
294 CDS_JAVA_HEAP_ONLY(_closed_archive_heap_region_mapped = true);
295 NOT_CDS_JAVA_HEAP_RETURN;
296 }
297 static bool closed_archive_heap_region_mapped() {
298 CDS_JAVA_HEAP_ONLY(return _closed_archive_heap_region_mapped);
299 NOT_CDS_JAVA_HEAP_RETURN_(false);
300 }
301 static void set_open_archive_heap_region_mapped() {
302 CDS_JAVA_HEAP_ONLY(_open_archive_heap_region_mapped = true);
303 NOT_CDS_JAVA_HEAP_RETURN;
304 }
305 static bool open_archive_heap_region_mapped() {
306 CDS_JAVA_HEAP_ONLY(return _open_archive_heap_region_mapped);
307 NOT_CDS_JAVA_HEAP_RETURN_(false);
308 }
309
310 static void fixup_mapped_heap_regions() NOT_CDS_JAVA_HEAP_RETURN;
311
312 inline static bool is_archived_object(oop p) NOT_CDS_JAVA_HEAP_RETURN_(false);
313
314 static void initialize_from_archived_subgraph(Klass* k) NOT_CDS_JAVA_HEAP_RETURN;
315
316 // NarrowOops stored in the CDS archive may use a different encoding scheme
317 // than CompressedOops::{base,shift} -- see FileMapInfo::map_heap_regions_impl.
318 // To decode them, do not use CompressedOops::decode_not_null. Use this
319 // function instead.
320 inline static oop decode_from_archive(narrowOop v) NOT_CDS_JAVA_HEAP_RETURN_(NULL);
321
322 static void init_narrow_oop_decoding(address base, int shift) NOT_CDS_JAVA_HEAP_RETURN;
323
324 static void patch_archived_heap_embedded_pointers(MemRegion mem, address oopmap,
325 size_t oopmap_in_bits) NOT_CDS_JAVA_HEAP_RETURN;
326
327 static void init_subgraph_entry_fields(Thread* THREAD) NOT_CDS_JAVA_HEAP_RETURN;
328 static void write_subgraph_info_table() NOT_CDS_JAVA_HEAP_RETURN;
329 static void serialize_subgraph_info_table_header(SerializeClosure* soc) NOT_CDS_JAVA_HEAP_RETURN;
330 };
331 #endif // SHARE_MEMORY_HEAPSHARED_HPP