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 int full_module_graph_only;
44 const char* field_name;
45 InstanceKlass* klass;
46 int offset;
47 BasicType type;
48 };
49
50 // A dump time sub-graph info for Klass _k. It includes the entry points
51 // (static fields in _k's mirror) of the archived sub-graphs reachable
52 // from _k's mirror. It also contains a list of Klasses of the objects
53 // within the sub-graphs.
54 class KlassSubGraphInfo: public CHeapObj<mtClass> {
55 private:
56 // The class that contains the static field(s) as the entry point(s)
57 // of archived object sub-graph(s).
58 Klass* _k;
59 // A list of classes need to be loaded and initialized before the archived
60 // object sub-graphs can be accessed at runtime.
61 GrowableArray<Klass*>* _subgraph_object_klasses;
62 // A list of _k's static fields as the entry points of archived sub-graphs.
63 // For each entry field, it is a tuple of field_offset, field_value and
64 // is_closed_archive flag.
65 GrowableArray<juint>* _subgraph_entry_fields;
66
67 public:
68 KlassSubGraphInfo(Klass* k) :
69 _k(k), _subgraph_object_klasses(NULL),
70 _subgraph_entry_fields(NULL) {}
71 ~KlassSubGraphInfo() {
72 if (_subgraph_object_klasses != NULL) {
73 delete _subgraph_object_klasses;
74 }
75 if (_subgraph_entry_fields != NULL) {
76 delete _subgraph_entry_fields;
77 }
78 };
79
80 Klass* klass() { return _k; }
81 GrowableArray<Klass*>* subgraph_object_klasses() {
82 return _subgraph_object_klasses;
83 }
84 GrowableArray<juint>* subgraph_entry_fields() {
85 return _subgraph_entry_fields;
86 }
87 void add_subgraph_entry_field(int static_field_offset, oop v,
88 bool is_closed_archive);
89 void add_subgraph_object_klass(Klass *orig_k, Klass *relocated_k);
90 int num_subgraph_object_klasses() {
91 return _subgraph_object_klasses == NULL ? 0 :
92 _subgraph_object_klasses->length();
93 }
94 };
95
96 // An archived record of object sub-graphs reachable from static
97 // fields within _k's mirror. The record is reloaded from the archive
98 // at runtime.
99 class ArchivedKlassSubGraphInfoRecord {
100 private:
101 Klass* _k;
102
103 // contains pairs of field offset and value for each subgraph entry field
104 Array<juint>* _entry_field_records;
105
106 // klasses of objects in archived sub-graphs referenced from the entry points
107 // (static fields) in the containing class
108 Array<Klass*>* _subgraph_object_klasses;
109 public:
110 ArchivedKlassSubGraphInfoRecord() :
111 _k(NULL), _entry_field_records(NULL), _subgraph_object_klasses(NULL) {}
112 void init(KlassSubGraphInfo* info);
113 Klass* klass() const { return _k; }
114 Array<juint>* entry_field_records() const { return _entry_field_records; }
115 Array<Klass*>* subgraph_object_klasses() const { return _subgraph_object_klasses; }
116 };
117 #endif // INCLUDE_CDS_JAVA_HEAP
118
119 class HeapShared: AllStatic {
120 friend class VerifySharedOopClosure;
121 private:
122
123 #if INCLUDE_CDS_JAVA_HEAP
124 static bool _closed_archive_heap_region_mapped;
125 static bool _open_archive_heap_region_mapped;
126 static bool _archive_heap_region_fixed;
127
128 static bool oop_equals(oop const& p1, oop const& p2) {
129 return p1 == p2;
130 }
131 static unsigned oop_hash(oop const& p);
132
133 typedef ResourceHashtable<oop, oop,
134 HeapShared::oop_hash,
135 HeapShared::oop_equals,
136 15889, // prime number
137 ResourceObj::C_HEAP> ArchivedObjectCache;
138 static ArchivedObjectCache* _archived_object_cache;
139
140 static bool klass_equals(Klass* const& p1, Klass* const& p2) {
141 return primitive_equals<Klass*>(p1, p2);
142 }
143
144 static unsigned klass_hash(Klass* const& klass) {
145 // Generate deterministic hashcode even if SharedBaseAddress is changed due to ASLR.
146 return primitive_hash<address>(address(klass) - SharedBaseAddress);
147 }
148
149 class DumpTimeKlassSubGraphInfoTable
150 : public ResourceHashtable<Klass*, KlassSubGraphInfo,
151 HeapShared::klass_hash,
152 HeapShared::klass_equals,
153 137, // prime number
154 ResourceObj::C_HEAP> {
155 public:
156 int _count;
157 };
158
159 public: // solaris compiler wants this for RunTimeKlassSubGraphInfoTable
160 inline static bool record_equals_compact_hashtable_entry(
161 const ArchivedKlassSubGraphInfoRecord* value, const Klass* key, int len_unused) {
162 return (value->klass() == key);
163 }
164
165 private:
166 typedef OffsetCompactHashtable<
167 const Klass*,
168 const ArchivedKlassSubGraphInfoRecord*,
169 record_equals_compact_hashtable_entry
170 > RunTimeKlassSubGraphInfoTable;
171
172 static DumpTimeKlassSubGraphInfoTable* _dump_time_subgraph_info_table;
173 static RunTimeKlassSubGraphInfoTable _run_time_subgraph_info_table;
174
175 static void check_closed_archive_heap_region_object(InstanceKlass* k,
176 Thread* THREAD);
177
178 static void archive_object_subgraphs(ArchivableStaticFieldInfo fields[],
179 int num,
180 bool is_closed_archive,
181 Thread* THREAD);
182
183 // Archive object sub-graph starting from the given static field
184 // in Klass k's mirror.
185 static void archive_reachable_objects_from_static_field(
186 InstanceKlass* k, const char* klass_name,
187 int field_offset, const char* field_name,
188 bool is_closed_archive, TRAPS);
189
190 static void verify_subgraph_from_static_field(
191 InstanceKlass* k, int field_offset) PRODUCT_RETURN;
192 static void verify_reachable_objects_from(oop obj, bool is_archived) PRODUCT_RETURN;
193 static void verify_subgraph_from(oop orig_obj) PRODUCT_RETURN;
194
195 static KlassSubGraphInfo* get_subgraph_info(Klass *k);
196
197 static void init_subgraph_entry_fields(ArchivableStaticFieldInfo fields[],
198 int num, Thread* THREAD);
199
200 // Used by decode_from_archive
201 static address _narrow_oop_base;
202 static int _narrow_oop_shift;
203
204 typedef ResourceHashtable<oop, bool,
205 HeapShared::oop_hash,
206 HeapShared::oop_equals,
207 15889, // prime number
208 ResourceObj::C_HEAP> SeenObjectsTable;
209
210 static SeenObjectsTable *_seen_objects_table;
211
212 static void init_seen_objects_table() {
213 assert(_seen_objects_table == NULL, "must be");
214 _seen_objects_table = new (ResourceObj::C_HEAP, mtClass)SeenObjectsTable();
215 }
216 static void delete_seen_objects_table() {
217 assert(_seen_objects_table != NULL, "must be");
218 delete _seen_objects_table;
219 _seen_objects_table = NULL;
220 }
221
222 // Statistics (for one round of start_recording_subgraph ... done_recording_subgraph)
223 static int _num_new_walked_objs;
224 static int _num_new_archived_objs;
225 static int _num_old_recorded_klasses;
226
227 // Statistics (for all archived subgraphs)
228 static int _num_total_subgraph_recordings;
229 static int _num_total_walked_objs;
230 static int _num_total_archived_objs;
231 static int _num_total_recorded_klasses;
232 static int _num_total_verifications;
233
234 static void start_recording_subgraph(InstanceKlass *k, const char* klass_name);
235 static void done_recording_subgraph(InstanceKlass *k, const char* klass_name);
236
237 static bool has_been_seen_during_subgraph_recording(oop obj);
238 static void set_has_been_seen_during_subgraph_recording(oop obj);
239
240 static void check_module_oop(oop orig_module_obj);
241
242 public:
243 static void reset_archived_object_states(TRAPS);
244 static void create_archived_object_cache() {
245 _archived_object_cache =
246 new (ResourceObj::C_HEAP, mtClass)ArchivedObjectCache();
247 }
248 static void destroy_archived_object_cache() {
249 delete _archived_object_cache;
250 _archived_object_cache = NULL;
251 }
252 static ArchivedObjectCache* archived_object_cache() {
253 return _archived_object_cache;
254 }
255
256 static oop find_archived_heap_object(oop obj);
257 static oop archive_heap_object(oop obj, Thread* THREAD);
258 static oop materialize_archived_object(narrowOop v);
259
260 static void archive_klass_objects(Thread* THREAD);
261
262 static void set_archive_heap_region_fixed() {
263 _archive_heap_region_fixed = true;
264 }
265 static bool archive_heap_region_fixed() {
266 return _archive_heap_region_fixed;
267 }
268
269 static void archive_java_heap_objects(GrowableArray<MemRegion> *closed,
270 GrowableArray<MemRegion> *open);
271 static void copy_closed_archive_heap_objects(GrowableArray<MemRegion> * closed_archive);
272 static void copy_open_archive_heap_objects(GrowableArray<MemRegion> * open_archive);
273
274 static oop archive_reachable_objects_from(int level,
275 KlassSubGraphInfo* subgraph_info,
276 oop orig_obj,
277 bool is_closed_archive,
278 TRAPS);
279
280 static ResourceBitMap calculate_oopmap(MemRegion region);
281 #endif // INCLUDE_CDS_JAVA_HEAP
282
283 public:
284 static void run_full_gc_in_vm_thread() NOT_CDS_JAVA_HEAP_RETURN;
285
286 static bool is_heap_object_archiving_allowed() {
287 CDS_JAVA_HEAP_ONLY(return (UseG1GC && UseCompressedOops && UseCompressedClassPointers);)
288 NOT_CDS_JAVA_HEAP(return false;)
289 }
290
291 static bool is_heap_region(int idx) {
292 CDS_JAVA_HEAP_ONLY(return (idx >= MetaspaceShared::first_closed_archive_heap_region &&
293 idx <= MetaspaceShared::last_open_archive_heap_region));
294 NOT_CDS_JAVA_HEAP_RETURN_(false);
295 }
296
297 static void set_closed_archive_heap_region_mapped() {
298 CDS_JAVA_HEAP_ONLY(_closed_archive_heap_region_mapped = true);
299 NOT_CDS_JAVA_HEAP_RETURN;
300 }
301 static bool closed_archive_heap_region_mapped() {
302 CDS_JAVA_HEAP_ONLY(return _closed_archive_heap_region_mapped);
303 NOT_CDS_JAVA_HEAP_RETURN_(false);
304 }
305 static void set_open_archive_heap_region_mapped() {
306 CDS_JAVA_HEAP_ONLY(_open_archive_heap_region_mapped = true);
307 NOT_CDS_JAVA_HEAP_RETURN;
308 }
309 static bool open_archive_heap_region_mapped() {
310 CDS_JAVA_HEAP_ONLY(return _open_archive_heap_region_mapped);
311 NOT_CDS_JAVA_HEAP_RETURN_(false);
312 }
313
314 static void fixup_mapped_heap_regions() NOT_CDS_JAVA_HEAP_RETURN;
315
316 inline static bool is_archived_object(oop p) NOT_CDS_JAVA_HEAP_RETURN_(false);
317
318 static void initialize_from_archived_subgraph(Klass* k) NOT_CDS_JAVA_HEAP_RETURN;
319
320 // NarrowOops stored in the CDS archive may use a different encoding scheme
321 // than CompressedOops::{base,shift} -- see FileMapInfo::map_heap_regions_impl.
322 // To decode them, do not use CompressedOops::decode_not_null. Use this
323 // function instead.
324 inline static oop decode_from_archive(narrowOop v) NOT_CDS_JAVA_HEAP_RETURN_(NULL);
325
326 static void init_narrow_oop_decoding(address base, int shift) NOT_CDS_JAVA_HEAP_RETURN;
327
328 static void patch_archived_heap_embedded_pointers(MemRegion mem, address oopmap,
329 size_t oopmap_in_bits) NOT_CDS_JAVA_HEAP_RETURN;
330
331 static void init_subgraph_entry_fields(Thread* THREAD) NOT_CDS_JAVA_HEAP_RETURN;
332 static void write_subgraph_info_table() NOT_CDS_JAVA_HEAP_RETURN;
333 static void serialize_subgraph_info_table_header(SerializeClosure* soc) NOT_CDS_JAVA_HEAP_RETURN;
334 };
335 #endif // SHARE_MEMORY_HEAPSHARED_HPP