1 /*
2 * Copyright (c) 2018, 2025, 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_CDS_HEAPSHARED_HPP
26 #define SHARE_CDS_HEAPSHARED_HPP
27
28 #include "cds/dumpTimeClassInfo.hpp"
29 #include "cds/metaspaceShared.hpp"
30 #include "classfile/compactHashtable.hpp"
31 #include "classfile/javaClasses.hpp"
32 #include "gc/shared/gc_globals.hpp"
33 #include "memory/allocation.hpp"
34 #include "memory/allStatic.hpp"
35 #include "oops/compressedOops.hpp"
36 #include "oops/oop.hpp"
37 #include "oops/oopHandle.hpp"
38 #include "oops/oopsHierarchy.hpp"
39 #include "utilities/growableArray.hpp"
40 #include "utilities/resourceHash.hpp"
41
42 #if INCLUDE_CDS_JAVA_HEAP
43 class DumpedInternedStrings;
44 class FileMapInfo;
45 class KlassSubGraphInfo;
46 class MetaspaceObjToOopHandleTable;
47 class ResourceBitMap;
48
49 struct ArchivableStaticFieldInfo;
50 class ArchiveHeapInfo;
51
52 #define ARCHIVED_BOOT_LAYER_CLASS "jdk/internal/module/ArchivedBootLayer"
53 #define ARCHIVED_BOOT_LAYER_FIELD "archivedBootLayer"
54
55 // A dump time sub-graph info for Klass _k. It includes the entry points
56 // (static fields in _k's mirror) of the archived sub-graphs reachable
57 // from _k's mirror. It also contains a list of Klasses of the objects
58 // within the sub-graphs.
59 class KlassSubGraphInfo: public CHeapObj<mtClass> {
60 private:
61 // The class that contains the static field(s) as the entry point(s)
62 // of archived object sub-graph(s).
63 Klass* _k;
64 // A list of classes need to be loaded and initialized before the archived
65 // object sub-graphs can be accessed at runtime.
66 GrowableArray<Klass*>* _subgraph_object_klasses;
67 // A list of _k's static fields as the entry points of archived sub-graphs.
68 // For each entry field, it is a tuple of field_offset, field_value
69 GrowableArray<int>* _subgraph_entry_fields;
70
71 // Does this KlassSubGraphInfo belong to the archived full module graph
72 bool _is_full_module_graph;
73
74 // Does this KlassSubGraphInfo references any classes that were loaded while
75 // JvmtiExport::is_early_phase()!=true. If so, this KlassSubGraphInfo cannot be
76 // used at runtime if JVMTI ClassFileLoadHook is enabled.
77 bool _has_non_early_klasses;
78 static bool is_non_early_klass(Klass* k);
79 static void check_allowed_klass(InstanceKlass* ik);
80 public:
81 KlassSubGraphInfo(Klass* k, bool is_full_module_graph) :
82 _k(k), _subgraph_object_klasses(nullptr),
83 _subgraph_entry_fields(nullptr),
84 _is_full_module_graph(is_full_module_graph),
85 _has_non_early_klasses(false) {}
86
87 ~KlassSubGraphInfo() {
88 if (_subgraph_object_klasses != nullptr) {
89 delete _subgraph_object_klasses;
90 }
91 if (_subgraph_entry_fields != nullptr) {
92 delete _subgraph_entry_fields;
93 }
94 };
95
96 Klass* klass() { return _k; }
97 GrowableArray<Klass*>* subgraph_object_klasses() {
98 return _subgraph_object_klasses;
99 }
100 GrowableArray<int>* subgraph_entry_fields() {
101 return _subgraph_entry_fields;
102 }
103 void add_subgraph_entry_field(int static_field_offset, oop v);
104 void add_subgraph_object_klass(Klass *orig_k);
105 int num_subgraph_object_klasses() {
106 return _subgraph_object_klasses == nullptr ? 0 :
107 _subgraph_object_klasses->length();
108 }
109 bool is_full_module_graph() const { return _is_full_module_graph; }
110 bool has_non_early_klasses() const { return _has_non_early_klasses; }
111 };
112
113 // An archived record of object sub-graphs reachable from static
114 // fields within _k's mirror. The record is reloaded from the archive
115 // at runtime.
116 class ArchivedKlassSubGraphInfoRecord {
117 private:
118 Klass* _k;
119 bool _is_full_module_graph;
120 bool _has_non_early_klasses;
121
122 // contains pairs of field offset and value for each subgraph entry field
123 Array<int>* _entry_field_records;
124
125 // klasses of objects in archived sub-graphs referenced from the entry points
126 // (static fields) in the containing class
127 Array<Klass*>* _subgraph_object_klasses;
128 public:
129 ArchivedKlassSubGraphInfoRecord() :
130 _k(nullptr), _entry_field_records(nullptr), _subgraph_object_klasses(nullptr) {}
131 void init(KlassSubGraphInfo* info);
132 Klass* klass() const { return _k; }
133 Array<int>* entry_field_records() const { return _entry_field_records; }
134 Array<Klass*>* subgraph_object_klasses() const { return _subgraph_object_klasses; }
135 bool is_full_module_graph() const { return _is_full_module_graph; }
136 bool has_non_early_klasses() const { return _has_non_early_klasses; }
137 };
138 #endif // INCLUDE_CDS_JAVA_HEAP
139
140 struct LoadedArchiveHeapRegion;
141
142 class HeapShared: AllStatic {
143 friend class VerifySharedOopClosure;
144
145 public:
146 static bool is_subgraph_root_class(InstanceKlass* ik);
147
148 // Scratch objects for archiving Klass::java_mirror()
149 static oop scratch_java_mirror(BasicType t) NOT_CDS_JAVA_HEAP_RETURN_(nullptr);
150 static oop scratch_java_mirror(Klass* k) NOT_CDS_JAVA_HEAP_RETURN_(nullptr);
151 static oop scratch_java_mirror(oop java_mirror) NOT_CDS_JAVA_HEAP_RETURN_(nullptr);
152 static bool is_archived_boot_layer_available(JavaThread* current) NOT_CDS_JAVA_HEAP_RETURN_(false);
153
154 private:
155 #if INCLUDE_CDS_JAVA_HEAP
156 static DumpedInternedStrings *_dumped_interned_strings;
157
158 // statistics
159 constexpr static int ALLOC_STAT_SLOTS = 16;
160 static size_t _alloc_count[ALLOC_STAT_SLOTS];
161 static size_t _alloc_size[ALLOC_STAT_SLOTS];
162 static size_t _total_obj_count;
163 static size_t _total_obj_size; // in HeapWords
164
165 static void count_allocation(size_t size);
166 static void print_stats();
167 static void debug_trace();
168 public:
169 static unsigned oop_hash(oop const& p);
170 static unsigned string_oop_hash(oop const& string) {
171 return java_lang_String::hash_code(string);
172 }
173
174 class CopyKlassSubGraphInfoToArchive;
175
176 class CachedOopInfo {
177 // Used by CDSHeapVerifier.
178 oop _orig_referrer;
179
180 // The location of this object inside ArchiveHeapWriter::_buffer
181 size_t _buffer_offset;
182
183 // One or more fields in this object are pointing to non-null oops.
184 bool _has_oop_pointers;
185
186 // One or more fields in this object are pointing to MetaspaceObj
187 bool _has_native_pointers;
188 public:
189 CachedOopInfo(oop orig_referrer, bool has_oop_pointers)
190 : _orig_referrer(orig_referrer),
191 _buffer_offset(0),
192 _has_oop_pointers(has_oop_pointers),
193 _has_native_pointers(false) {}
194 oop orig_referrer() const { return _orig_referrer; }
195 void set_buffer_offset(size_t offset) { _buffer_offset = offset; }
196 size_t buffer_offset() const { return _buffer_offset; }
197 bool has_oop_pointers() const { return _has_oop_pointers; }
198 bool has_native_pointers() const { return _has_native_pointers; }
199 void set_has_native_pointers() { _has_native_pointers = true; }
200 };
201
202 private:
203 static const int INITIAL_TABLE_SIZE = 15889; // prime number
204 static const int MAX_TABLE_SIZE = 1000000;
205 typedef ResizeableResourceHashtable<oop, CachedOopInfo,
206 AnyObj::C_HEAP,
207 mtClassShared,
208 HeapShared::oop_hash> ArchivedObjectCache;
209 static ArchivedObjectCache* _archived_object_cache;
210
211 class DumpTimeKlassSubGraphInfoTable
212 : public ResourceHashtable<Klass*, KlassSubGraphInfo,
213 137, // prime number
214 AnyObj::C_HEAP,
215 mtClassShared,
216 DumpTimeSharedClassTable_hash> {
217 public:
218 int _count;
219 };
220
221 public: // solaris compiler wants this for RunTimeKlassSubGraphInfoTable
222 inline static bool record_equals_compact_hashtable_entry(
223 const ArchivedKlassSubGraphInfoRecord* value, const Klass* key, int len_unused) {
224 return (value->klass() == key);
225 }
226
227 private:
228 typedef OffsetCompactHashtable<
229 const Klass*,
230 const ArchivedKlassSubGraphInfoRecord*,
231 record_equals_compact_hashtable_entry
232 > RunTimeKlassSubGraphInfoTable;
233
234 static DumpTimeKlassSubGraphInfoTable* _dump_time_subgraph_info_table;
235 static RunTimeKlassSubGraphInfoTable _run_time_subgraph_info_table;
236
237 static CachedOopInfo make_cached_oop_info(oop obj);
238 static ArchivedKlassSubGraphInfoRecord* archive_subgraph_info(KlassSubGraphInfo* info);
239 static void archive_object_subgraphs(ArchivableStaticFieldInfo fields[],
240 bool is_full_module_graph);
241
242 // Archive object sub-graph starting from the given static field
243 // in Klass k's mirror.
244 static void archive_reachable_objects_from_static_field(
245 InstanceKlass* k, const char* klass_name,
246 int field_offset, const char* field_name);
247
248 static void verify_subgraph_from_static_field(
249 InstanceKlass* k, int field_offset) PRODUCT_RETURN;
250 static void verify_reachable_objects_from(oop obj) PRODUCT_RETURN;
251 static void verify_subgraph_from(oop orig_obj) PRODUCT_RETURN;
252 static void check_special_subgraph_classes();
253
254 static KlassSubGraphInfo* init_subgraph_info(Klass *k, bool is_full_module_graph);
255 static KlassSubGraphInfo* get_subgraph_info(Klass *k);
256
257 static void init_subgraph_entry_fields(TRAPS) NOT_CDS_JAVA_HEAP_RETURN;
258 static void init_subgraph_entry_fields(ArchivableStaticFieldInfo fields[], TRAPS);
259
260 // UseCompressedOops only: Used by decode_from_archive
261 static address _narrow_oop_base;
262 static int _narrow_oop_shift;
263
264 // !UseCompressedOops only: used to relocate pointers to the archived objects
265 static ptrdiff_t _runtime_delta;
266
267 typedef ResizeableResourceHashtable<oop, bool,
268 AnyObj::C_HEAP,
269 mtClassShared,
270 HeapShared::oop_hash> SeenObjectsTable;
271
272 static SeenObjectsTable *_seen_objects_table;
273
274 // The "special subgraph" contains all the archived objects that are reachable
275 // from the following roots:
276 // - interned strings
277 // - Klass::java_mirror() -- including aot-initialized mirrors such as those of Enum klasses.
278 // - ConstantPool::resolved_references()
279 // - Universe::<xxx>_exception_instance()
280 static KlassSubGraphInfo* _dump_time_special_subgraph; // for collecting info during dump time
281 static ArchivedKlassSubGraphInfoRecord* _run_time_special_subgraph; // for initializing classes during run time.
282
283 static GrowableArrayCHeap<oop, mtClassShared>* _pending_roots;
284 static GrowableArrayCHeap<OopHandle, mtClassShared>* _root_segments;
285 static int _root_segment_max_size_elems;
286 static OopHandle _scratch_basic_type_mirrors[T_VOID+1];
287 static MetaspaceObjToOopHandleTable* _scratch_java_mirror_table;
288 static MetaspaceObjToOopHandleTable* _scratch_references_table;
289
290 static void init_seen_objects_table() {
291 assert(_seen_objects_table == nullptr, "must be");
292 _seen_objects_table = new (mtClass)SeenObjectsTable(INITIAL_TABLE_SIZE, MAX_TABLE_SIZE);
293 }
294 static void delete_seen_objects_table() {
295 assert(_seen_objects_table != nullptr, "must be");
296 delete _seen_objects_table;
297 _seen_objects_table = nullptr;
298 }
299
300 // Statistics (for one round of start_recording_subgraph ... done_recording_subgraph)
301 static int _num_new_walked_objs;
302 static int _num_new_archived_objs;
303 static int _num_old_recorded_klasses;
304
305 // Statistics (for all archived subgraphs)
306 static int _num_total_subgraph_recordings;
307 static int _num_total_walked_objs;
308 static int _num_total_archived_objs;
309 static int _num_total_recorded_klasses;
310 static int _num_total_verifications;
311
312 static void start_recording_subgraph(InstanceKlass *k, const char* klass_name,
313 bool is_full_module_graph);
314 static void done_recording_subgraph(InstanceKlass *k, const char* klass_name);
315
316 static bool has_been_seen_during_subgraph_recording(oop obj);
317 static void set_has_been_seen_during_subgraph_recording(oop obj);
318 static bool archive_object(oop obj, KlassSubGraphInfo* subgraph_info);
319
320 static void resolve_classes_for_subgraphs(JavaThread* current, ArchivableStaticFieldInfo fields[]);
321 static void resolve_classes_for_subgraph_of(JavaThread* current, Klass* k);
322 static void clear_archived_roots_of(Klass* k);
323 static const ArchivedKlassSubGraphInfoRecord*
324 resolve_or_init_classes_for_subgraph_of(Klass* k, bool do_init, TRAPS);
325 static void resolve_or_init(const char* klass_name, bool do_init, TRAPS);
326 static void resolve_or_init(Klass* k, bool do_init, TRAPS);
327 static void init_archived_fields_for(Klass* k, const ArchivedKlassSubGraphInfoRecord* record);
328
329 static int init_loaded_regions(FileMapInfo* mapinfo, LoadedArchiveHeapRegion* loaded_regions,
330 MemRegion& archive_space);
331 static void sort_loaded_regions(LoadedArchiveHeapRegion* loaded_regions, int num_loaded_regions,
332 uintptr_t buffer);
333 static bool load_regions(FileMapInfo* mapinfo, LoadedArchiveHeapRegion* loaded_regions,
334 int num_loaded_regions, uintptr_t buffer);
335 static void init_loaded_heap_relocation(LoadedArchiveHeapRegion* reloc_info,
336 int num_loaded_regions);
337 static void fill_failed_loaded_region();
338 static void mark_native_pointers(oop orig_obj);
339 static bool has_been_archived(oop orig_obj);
340 static void prepare_resolved_references();
341 static void archive_strings();
342 static void archive_subgraphs();
343
344 public:
345 static void reset_archived_object_states(TRAPS);
346 static void create_archived_object_cache() {
347 _archived_object_cache =
348 new (mtClass)ArchivedObjectCache(INITIAL_TABLE_SIZE, MAX_TABLE_SIZE);
349 }
350 static void destroy_archived_object_cache() {
351 delete _archived_object_cache;
352 _archived_object_cache = nullptr;
353 }
354 static ArchivedObjectCache* archived_object_cache() {
355 return _archived_object_cache;
356 }
357
358 static int archive_exception_instance(oop exception);
359
360 static bool archive_reachable_objects_from(int level,
361 KlassSubGraphInfo* subgraph_info,
362 oop orig_obj);
363
364 static void add_to_dumped_interned_strings(oop string);
365 static bool is_dumped_interned_string(oop o);
366
367 // Scratch objects for archiving Klass::java_mirror()
368 static void set_scratch_java_mirror(Klass* k, oop mirror);
369 static void remove_scratch_objects(Klass* k);
370 static void get_pointer_info(oop src_obj, bool& has_oop_pointers, bool& has_native_pointers);
371 static void set_has_native_pointers(oop src_obj);
372
373 // We use the HeapShared::roots() array to make sure that objects stored in the
374 // archived heap region are not prematurely collected. These roots include:
375 //
376 // - mirrors of classes that have not yet been loaded.
377 // - ConstantPool::resolved_references() of classes that have not yet been loaded.
378 // - ArchivedKlassSubGraphInfoRecords that have not been initialized
379 // - java.lang.Module objects that have not yet been added to the module graph
380 //
381 // When a mirror M becomes referenced by a newly loaded class K, M will be removed
382 // from HeapShared::roots() via clear_root(), and K will be responsible for
383 // keeping M alive.
384 //
385 // Other types of roots are also cleared similarly when they become referenced.
386
387 // Dump-time only. Returns the index of the root, which can be used at run time to read
388 // the root using get_root(index, ...).
389 static int append_root(oop obj);
390 static GrowableArrayCHeap<oop, mtClassShared>* pending_roots() { return _pending_roots; }
391
392 // Dump-time and runtime
393 static objArrayOop root_segment(int segment_idx);
394 static oop get_root(int index, bool clear=false);
395
396 // Run-time only
397 static void clear_root(int index);
398
399 static void get_segment_indexes(int index, int& segment_index, int& internal_index);
400
401 static void setup_test_class(const char* test_class_name) PRODUCT_RETURN;
402 #endif // INCLUDE_CDS_JAVA_HEAP
403
404 public:
405 static void write_heap(ArchiveHeapInfo* heap_info) NOT_CDS_JAVA_HEAP_RETURN;
406 static objArrayOop scratch_resolved_references(ConstantPool* src);
407 static void add_scratch_resolved_references(ConstantPool* src, objArrayOop dest) NOT_CDS_JAVA_HEAP_RETURN;
408 static void init_dumping() NOT_CDS_JAVA_HEAP_RETURN;
409 static void init_scratch_objects(TRAPS) NOT_CDS_JAVA_HEAP_RETURN;
410 static void init_box_classes(TRAPS) NOT_CDS_JAVA_HEAP_RETURN;
411 static bool is_heap_region(int idx) {
412 CDS_JAVA_HEAP_ONLY(return (idx == MetaspaceShared::hp);)
413 NOT_CDS_JAVA_HEAP_RETURN_(false);
414 }
415
416 static void resolve_classes(JavaThread* current) NOT_CDS_JAVA_HEAP_RETURN;
417 static void initialize_from_archived_subgraph(JavaThread* current, Klass* k) NOT_CDS_JAVA_HEAP_RETURN;
418
419 static void init_for_dumping(TRAPS) NOT_CDS_JAVA_HEAP_RETURN;
420 static void write_subgraph_info_table() NOT_CDS_JAVA_HEAP_RETURN;
421 static void add_root_segment(objArrayOop segment_oop) NOT_CDS_JAVA_HEAP_RETURN;
422 static void init_root_segment_sizes(int max_size_elems) NOT_CDS_JAVA_HEAP_RETURN;
423 static void serialize_tables(SerializeClosure* soc) NOT_CDS_JAVA_HEAP_RETURN;
424
425 #ifndef PRODUCT
426 static bool is_a_test_class_in_unnamed_module(Klass* ik) NOT_CDS_JAVA_HEAP_RETURN_(false);
427 static void initialize_test_class_from_archive(TRAPS) NOT_CDS_JAVA_HEAP_RETURN;
428 #endif
429
430 static void initialize_java_lang_invoke(TRAPS) NOT_CDS_JAVA_HEAP_RETURN;
431 static void init_classes_for_special_subgraph(Handle loader, TRAPS) NOT_CDS_JAVA_HEAP_RETURN;
432
433 static bool is_lambda_form_klass(InstanceKlass* ik) NOT_CDS_JAVA_HEAP_RETURN_(false);
434 static bool is_lambda_proxy_klass(InstanceKlass* ik) NOT_CDS_JAVA_HEAP_RETURN_(false);
435 static bool is_string_concat_klass(InstanceKlass* ik) NOT_CDS_JAVA_HEAP_RETURN_(false);
436 static bool is_archivable_hidden_klass(InstanceKlass* ik) NOT_CDS_JAVA_HEAP_RETURN_(false);
437
438 // Used by AOTArtifactFinder
439 static void start_scanning_for_oops();
440 static void end_scanning_for_oops();
441 static void scan_java_class(Klass* k);
442 static void scan_java_mirror(oop orig_mirror);
443 static void copy_and_rescan_aot_inited_mirror(InstanceKlass* ik);
444 };
445
446 #if INCLUDE_CDS_JAVA_HEAP
447 class DumpedInternedStrings :
448 public ResizeableResourceHashtable<oop, bool,
449 AnyObj::C_HEAP,
450 mtClassShared,
451 HeapShared::string_oop_hash>
452 {
453 public:
454 DumpedInternedStrings(unsigned size, unsigned max_size) :
455 ResizeableResourceHashtable<oop, bool,
456 AnyObj::C_HEAP,
457 mtClassShared,
458 HeapShared::string_oop_hash>(size, max_size) {}
459 };
460 #endif
461
462 #endif // SHARE_CDS_HEAPSHARED_HPP