1 /*
2 * Copyright (c) 2018, 2024, 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/cds_globals.hpp"
29 #include "cds/dumpTimeClassInfo.hpp"
30 #include "cds/metaspaceShared.hpp"
31 #include "classfile/compactHashtable.hpp"
32 #include "classfile/javaClasses.hpp"
33 #include "gc/shared/gc_globals.hpp"
34 #include "memory/allocation.hpp"
35 #include "memory/allStatic.hpp"
36 #include "oops/compressedOops.hpp"
37 #include "oops/oop.hpp"
38 #include "oops/oopHandle.hpp"
39 #include "oops/oopsHierarchy.hpp"
40 #include "utilities/growableArray.hpp"
41 #include "utilities/resourceHash.hpp"
42
43 #if INCLUDE_CDS_JAVA_HEAP
44 class DumpedInternedStrings;
45 class FileMapInfo;
46 class KlassSubGraphInfo;
47 class MetaspaceObjToOopHandleTable;
48 class ResourceBitMap;
49
50 struct ArchivableStaticFieldInfo;
51 class ArchiveHeapInfo;
52
53 #define ARCHIVED_BOOT_LAYER_CLASS "jdk/internal/module/ArchivedBootLayer"
54 #define ARCHIVED_BOOT_LAYER_FIELD "archivedBootLayer"
55
56 // A dump time sub-graph info for Klass _k. It includes the entry points
57 // (static fields in _k's mirror) of the archived sub-graphs reachable
58 // from _k's mirror. It also contains a list of Klasses of the objects
59 // within the sub-graphs.
60 class KlassSubGraphInfo: public CHeapObj<mtClass> {
61 private:
62 // The class that contains the static field(s) as the entry point(s)
63 // of archived object sub-graph(s).
64 Klass* _k;
65 // A list of classes need to be loaded and initialized before the archived
66 // object sub-graphs can be accessed at runtime.
67 GrowableArray<Klass*>* _subgraph_object_klasses;
68 // A list of _k's static fields as the entry points of archived sub-graphs.
69 // For each entry field, it is a tuple of field_offset, field_value
70 GrowableArray<int>* _subgraph_entry_fields;
71
72 // Does this KlassSubGraphInfo belong to the archived full module graph
73 bool _is_full_module_graph;
74
75 // Does this KlassSubGraphInfo references any classes that were loaded while
76 // JvmtiExport::is_early_phase()!=true. If so, this KlassSubGraphInfo cannot be
77 // used at runtime if JVMTI ClassFileLoadHook is enabled.
78 bool _has_non_early_klasses;
79 static bool is_non_early_klass(Klass* k);
80 static void check_allowed_klass(InstanceKlass* ik);
81 public:
82 KlassSubGraphInfo(Klass* k, bool is_full_module_graph) :
83 _k(k), _subgraph_object_klasses(nullptr),
84 _subgraph_entry_fields(nullptr),
85 _is_full_module_graph(is_full_module_graph),
86 _has_non_early_klasses(false) {}
87
88 ~KlassSubGraphInfo() {
89 if (_subgraph_object_klasses != nullptr) {
90 delete _subgraph_object_klasses;
91 }
92 if (_subgraph_entry_fields != nullptr) {
93 delete _subgraph_entry_fields;
94 }
95 };
96
97 Klass* klass() { return _k; }
98 GrowableArray<Klass*>* subgraph_object_klasses() {
99 return _subgraph_object_klasses;
100 }
101 GrowableArray<int>* subgraph_entry_fields() {
102 return _subgraph_entry_fields;
103 }
104 void add_subgraph_entry_field(int static_field_offset, oop v);
105 void add_subgraph_object_klass(Klass *orig_k);
106 int num_subgraph_object_klasses() {
107 return _subgraph_object_klasses == nullptr ? 0 :
108 _subgraph_object_klasses->length();
109 }
110 bool is_full_module_graph() const { return _is_full_module_graph; }
111 bool has_non_early_klasses() const { return _has_non_early_klasses; }
112 };
113
114 // An archived record of object sub-graphs reachable from static
115 // fields within _k's mirror. The record is reloaded from the archive
116 // at runtime.
117 class ArchivedKlassSubGraphInfoRecord {
118 private:
119 Klass* _k;
120 bool _is_full_module_graph;
121 bool _has_non_early_klasses;
122
123 // contains pairs of field offset and value for each subgraph entry field
124 Array<int>* _entry_field_records;
125
126 // klasses of objects in archived sub-graphs referenced from the entry points
127 // (static fields) in the containing class
128 Array<Klass*>* _subgraph_object_klasses;
129 public:
130 ArchivedKlassSubGraphInfoRecord() :
131 _k(nullptr), _entry_field_records(nullptr), _subgraph_object_klasses(nullptr) {}
132 void init(KlassSubGraphInfo* info);
133 Klass* klass() const { return _k; }
134 Array<int>* entry_field_records() const { return _entry_field_records; }
135 Array<Klass*>* subgraph_object_klasses() const { return _subgraph_object_klasses; }
136 bool is_full_module_graph() const { return _is_full_module_graph; }
137 bool has_non_early_klasses() const { return _has_non_early_klasses; }
138 };
139 #endif // INCLUDE_CDS_JAVA_HEAP
140
141 struct LoadedArchiveHeapRegion;
142
143 class HeapShared: AllStatic {
144 friend class VerifySharedOopClosure;
145
146 public:
147 // Can this VM write a heap region into the CDS archive?
148 static bool can_write() {
149 CDS_JAVA_HEAP_ONLY(
150 if (_disable_writing) {
151 return false;
152 }
153 // Need compressed class pointers for heap region dump.
154 if (!UseCompressedClassPointers) {
155 return false;
156 }
157 // Almost all GCs support heap region dump, except ZGC (so far).
158 return !UseZGC;
159 )
160 NOT_CDS_JAVA_HEAP(return false;)
161 }
162
163 static void disable_writing() {
164 CDS_JAVA_HEAP_ONLY(_disable_writing = true;)
165 }
166
167 static bool is_subgraph_root_class(InstanceKlass* ik);
168
169 // Scratch objects for archiving Klass::java_mirror()
170 static oop scratch_java_mirror(BasicType t) NOT_CDS_JAVA_HEAP_RETURN_(nullptr);
171 static oop scratch_java_mirror(Klass* k) NOT_CDS_JAVA_HEAP_RETURN_(nullptr);
172 static oop scratch_java_mirror(oop java_mirror) NOT_CDS_JAVA_HEAP_RETURN_(nullptr);
173 static bool is_archived_boot_layer_available(JavaThread* current) NOT_CDS_JAVA_HEAP_RETURN_(false);
174
175 // Look for all hidden classes that are referenced by archived objects.
176 static void start_finding_required_hidden_classes() NOT_CDS_JAVA_HEAP_RETURN;
177 static void find_required_hidden_classes_in_object(oop o) NOT_CDS_JAVA_HEAP_RETURN;
178 static void end_finding_required_hidden_classes() NOT_CDS_JAVA_HEAP_RETURN;
179
180 private:
181 #if INCLUDE_CDS_JAVA_HEAP
182 static bool _disable_writing;
183 static DumpedInternedStrings *_dumped_interned_strings;
184
185 // statistics
186 constexpr static int ALLOC_STAT_SLOTS = 16;
187 static size_t _alloc_count[ALLOC_STAT_SLOTS];
188 static size_t _alloc_size[ALLOC_STAT_SLOTS];
189 static size_t _total_obj_count;
190 static size_t _total_obj_size; // in HeapWords
191
192 static void count_allocation(size_t size);
193 static void print_stats();
194 static void debug_trace();
195 public:
196 static unsigned oop_hash(oop const& p);
197 static unsigned string_oop_hash(oop const& string) {
198 return java_lang_String::hash_code(string);
199 }
200
201 class CopyKlassSubGraphInfoToArchive;
202
203 class CachedOopInfo {
204 // Used by CDSHeapVerifier.
205 oop _orig_referrer;
206
207 // The location of this object inside ArchiveHeapWriter::_buffer
208 size_t _buffer_offset;
209
210 // One or more fields in this object are pointing to non-null oops.
211 bool _has_oop_pointers;
212
213 // One or more fields in this object are pointing to MetaspaceObj
214 bool _has_native_pointers;
215 public:
216 CachedOopInfo(oop orig_referrer, bool has_oop_pointers)
217 : _orig_referrer(orig_referrer),
218 _buffer_offset(0),
219 _has_oop_pointers(has_oop_pointers),
220 _has_native_pointers(false) {}
221 oop orig_referrer() const { return _orig_referrer; }
222 void set_buffer_offset(size_t offset) { _buffer_offset = offset; }
223 size_t buffer_offset() const { return _buffer_offset; }
224 bool has_oop_pointers() const { return _has_oop_pointers; }
225 bool has_native_pointers() const { return _has_native_pointers; }
226 void set_has_native_pointers() { _has_native_pointers = true; }
227 };
228
229 private:
230 static const int INITIAL_TABLE_SIZE = 15889; // prime number
231 static const int MAX_TABLE_SIZE = 1000000;
232 typedef ResizeableResourceHashtable<oop, CachedOopInfo,
233 AnyObj::C_HEAP,
234 mtClassShared,
235 HeapShared::oop_hash> ArchivedObjectCache;
236 static ArchivedObjectCache* _archived_object_cache;
237
238 class DumpTimeKlassSubGraphInfoTable
239 : public ResourceHashtable<Klass*, KlassSubGraphInfo,
240 137, // prime number
241 AnyObj::C_HEAP,
242 mtClassShared,
243 DumpTimeSharedClassTable_hash> {
244 public:
245 int _count;
246 };
247
248 public: // solaris compiler wants this for RunTimeKlassSubGraphInfoTable
249 inline static bool record_equals_compact_hashtable_entry(
250 const ArchivedKlassSubGraphInfoRecord* value, const Klass* key, int len_unused) {
251 return (value->klass() == key);
252 }
253
254 private:
255 typedef OffsetCompactHashtable<
256 const Klass*,
257 const ArchivedKlassSubGraphInfoRecord*,
258 record_equals_compact_hashtable_entry
259 > RunTimeKlassSubGraphInfoTable;
260
261 static DumpTimeKlassSubGraphInfoTable* _dump_time_subgraph_info_table;
262 static RunTimeKlassSubGraphInfoTable _run_time_subgraph_info_table;
263
264 class FindRequiredHiddenClassesOopClosure;
265 static void find_required_hidden_classes_helper(ArchivableStaticFieldInfo fields[]);
266
267 static CachedOopInfo make_cached_oop_info(oop obj);
268 static ArchivedKlassSubGraphInfoRecord* archive_subgraph_info(KlassSubGraphInfo* info);
269 static void archive_object_subgraphs(ArchivableStaticFieldInfo fields[],
270 bool is_full_module_graph);
271
272 // Archive object sub-graph starting from the given static field
273 // in Klass k's mirror.
274 static void archive_reachable_objects_from_static_field(
275 InstanceKlass* k, const char* klass_name,
276 int field_offset, const char* field_name);
277
278 static void verify_subgraph_from_static_field(
279 InstanceKlass* k, int field_offset) PRODUCT_RETURN;
280 static void verify_reachable_objects_from(oop obj) PRODUCT_RETURN;
281 static void verify_subgraph_from(oop orig_obj) PRODUCT_RETURN;
282 static void check_special_subgraph_classes();
283
284 static KlassSubGraphInfo* init_subgraph_info(Klass *k, bool is_full_module_graph);
285 static KlassSubGraphInfo* get_subgraph_info(Klass *k);
286
287 static void init_subgraph_entry_fields(TRAPS) NOT_CDS_JAVA_HEAP_RETURN;
288 static void init_subgraph_entry_fields(ArchivableStaticFieldInfo fields[], TRAPS);
289
290 // UseCompressedOops only: Used by decode_from_archive
291 static address _narrow_oop_base;
292 static int _narrow_oop_shift;
293
294 // !UseCompressedOops only: used to relocate pointers to the archived objects
295 static ptrdiff_t _runtime_delta;
296
297 typedef ResizeableResourceHashtable<oop, bool,
298 AnyObj::C_HEAP,
299 mtClassShared,
300 HeapShared::oop_hash> SeenObjectsTable;
301
302 static SeenObjectsTable *_seen_objects_table;
303
304 // The "special subgraph" contains all the archived objects that are reachable
305 // from the following roots:
306 // - interned strings
307 // - Klass::java_mirror() -- including aot-initialized mirrors such as those of Enum klasses.
308 // - ConstantPool::resolved_references()
309 // - Universe::<xxx>_exception_instance()
310 static KlassSubGraphInfo* _dump_time_special_subgraph; // for collecting info during dump time
311 static ArchivedKlassSubGraphInfoRecord* _run_time_special_subgraph; // for initializing classes during run time.
312
313 static GrowableArrayCHeap<OopHandle, mtClassShared>* _pending_roots;
314 static GrowableArrayCHeap<OopHandle, mtClassShared>* _root_segments;
315 static GrowableArrayCHeap<oop, mtClassShared>* _trace; // for debugging unarchivable objects
316 static GrowableArrayCHeap<const char*, mtClassShared>* _context; // for debugging unarchivable objects
317 static int _root_segment_max_size_elems;
318 static OopHandle _scratch_basic_type_mirrors[T_VOID+1];
319 static MetaspaceObjToOopHandleTable* _scratch_java_mirror_table;
320 static MetaspaceObjToOopHandleTable* _scratch_references_table;
321
322 static void init_seen_objects_table() {
323 assert(_seen_objects_table == nullptr, "must be");
324 _seen_objects_table = new (mtClass)SeenObjectsTable(INITIAL_TABLE_SIZE, MAX_TABLE_SIZE);
325 }
326 static void delete_seen_objects_table() {
327 assert(_seen_objects_table != nullptr, "must be");
328 delete _seen_objects_table;
329 _seen_objects_table = nullptr;
330 }
331
332 class ArchivingObjectMark;
333 class ContextMark;
334
335 // Statistics (for one round of start_recording_subgraph ... done_recording_subgraph)
336 static int _num_new_walked_objs;
337 static int _num_new_archived_objs;
338 static int _num_old_recorded_klasses;
339
340 // Statistics (for all archived subgraphs)
341 static int _num_total_subgraph_recordings;
342 static int _num_total_walked_objs;
343 static int _num_total_archived_objs;
344 static int _num_total_recorded_klasses;
345 static int _num_total_verifications;
346
347 static void start_recording_subgraph(InstanceKlass *k, const char* klass_name,
348 bool is_full_module_graph);
349 static void done_recording_subgraph(InstanceKlass *k, const char* klass_name);
350
351 static bool has_been_seen_during_subgraph_recording(oop obj);
352 static void set_has_been_seen_during_subgraph_recording(oop obj);
353 static bool archive_object(oop obj);
354 static void copy_aot_initialized_mirror(Klass* orig_k, oop orig_mirror, oop m);
355 static void copy_interned_strings();
356
357 static void resolve_classes_for_subgraphs(JavaThread* current, ArchivableStaticFieldInfo fields[]);
358 static void resolve_classes_for_subgraph_of(JavaThread* current, Klass* k);
359 static void clear_archived_roots_of(Klass* k);
360 static const ArchivedKlassSubGraphInfoRecord*
361 resolve_or_init_classes_for_subgraph_of(Klass* k, bool do_init, TRAPS);
362 static void resolve_or_init(const char* klass_name, bool do_init, TRAPS);
363 static void resolve_or_init(Klass* k, bool do_init, TRAPS);
364 static void init_archived_fields_for(Klass* k, const ArchivedKlassSubGraphInfoRecord* record);
365
366 static int init_loaded_regions(FileMapInfo* mapinfo, LoadedArchiveHeapRegion* loaded_regions,
367 MemRegion& archive_space);
368 static void sort_loaded_regions(LoadedArchiveHeapRegion* loaded_regions, int num_loaded_regions,
369 uintptr_t buffer);
370 static bool load_regions(FileMapInfo* mapinfo, LoadedArchiveHeapRegion* loaded_regions,
371 int num_loaded_regions, uintptr_t buffer);
372 static void init_loaded_heap_relocation(LoadedArchiveHeapRegion* reloc_info,
373 int num_loaded_regions);
374 static void fill_failed_loaded_region();
375 static void mark_native_pointers(oop orig_obj);
376 static bool has_been_archived(oop orig_obj);
377 static void prepare_resolved_references();
378 static void archive_java_mirrors();
379 static void archive_strings();
380 static void copy_special_subgraph();
381
382 class AOTInitializedClassScanner;
383 static void find_all_aot_initialized_classes();
384 static void find_all_aot_initialized_classes_helper();
385 static bool scan_for_aot_initialized_classes(oop obj);
386
387 public:
388 static void exit_on_error();
389 static void reset_archived_object_states(TRAPS);
390 static void create_archived_object_cache() {
391 _archived_object_cache =
392 new (mtClass)ArchivedObjectCache(INITIAL_TABLE_SIZE, MAX_TABLE_SIZE);
393 }
394 static void destroy_archived_object_cache() {
395 delete _archived_object_cache;
396 _archived_object_cache = nullptr;
397 }
398 static ArchivedObjectCache* archived_object_cache() {
399 return _archived_object_cache;
400 }
401
402 static int archive_exception_instance(oop exception);
403 static void archive_objects(ArchiveHeapInfo* heap_info);
404 static void copy_objects();
405
406 static bool archive_reachable_objects_from(int level,
407 KlassSubGraphInfo* subgraph_info,
408 oop orig_obj);
409
410 static void add_to_dumped_interned_strings(oop string);
411
412 static void track_scratch_object(oop orig_obj, oop scratch_obj);
413
414 // Scratch objects for archiving Klass::java_mirror()
415 static void set_scratch_java_mirror(Klass* k, oop mirror);
416 static void remove_scratch_objects(Klass* k);
417 static void get_pointer_info(oop src_obj, bool& has_oop_pointers, bool& has_native_pointers);
418 static void set_has_native_pointers(oop src_obj);
419
420 // We use the HeapShared::roots() array to make sure that objects stored in the
421 // archived heap region are not prematurely collected. These roots include:
422 //
423 // - mirrors of classes that have not yet been loaded.
424 // - ConstantPool::resolved_references() of classes that have not yet been loaded.
425 // - ArchivedKlassSubGraphInfoRecords that have not been initialized
426 // - java.lang.Module objects that have not yet been added to the module graph
427 //
428 // When a mirror M becomes referenced by a newly loaded class K, M will be removed
429 // from HeapShared::roots() via clear_root(), and K will be responsible for
430 // keeping M alive.
431 //
432 // Other types of roots are also cleared similarly when they become referenced.
433
434 // Dump-time only. Returns the index of the root, which can be used at run time to read
435 // the root using get_root(index, ...).
436 static int append_root(oop obj);
437 static GrowableArrayCHeap<OopHandle, mtClassShared>* pending_roots() { return _pending_roots; }
438
439 // Dump-time and runtime
440 static objArrayOop root_segment(int segment_idx);
441 static oop get_root(int index, bool clear=false);
442
443 // Run-time only
444 static void clear_root(int index);
445 static void get_segment_indexes(int index, int& segment_index, int& internal_index);
446 static void setup_test_class(const char* test_class_name) PRODUCT_RETURN;
447 #endif // INCLUDE_CDS_JAVA_HEAP
448
449 public:
450 static oop orig_to_scratch_object(oop orig_obj);
451 static objArrayOop scratch_resolved_references(ConstantPool* src);
452 static void add_scratch_resolved_references(ConstantPool* src, objArrayOop dest) NOT_CDS_JAVA_HEAP_RETURN;
453 static void init_scratch_objects(TRAPS) NOT_CDS_JAVA_HEAP_RETURN;
454 static void init_box_classes(TRAPS) NOT_CDS_JAVA_HEAP_RETURN;
455 static bool is_heap_region(int idx) {
456 CDS_JAVA_HEAP_ONLY(return (idx == MetaspaceShared::hp);)
457 NOT_CDS_JAVA_HEAP_RETURN_(false);
458 }
459
460 static void resolve_classes(JavaThread* current) NOT_CDS_JAVA_HEAP_RETURN;
461 static void initialize_from_archived_subgraph(JavaThread* current, Klass* k) NOT_CDS_JAVA_HEAP_RETURN;
462
463 static void init_for_dumping(TRAPS) NOT_CDS_JAVA_HEAP_RETURN;
464 static void write_subgraph_info_table() NOT_CDS_JAVA_HEAP_RETURN;
465 static void add_root_segment(objArrayOop segment_oop) NOT_CDS_JAVA_HEAP_RETURN;
466 static void init_root_segment_sizes(int max_size_elems) NOT_CDS_JAVA_HEAP_RETURN;
467 static void serialize_tables(SerializeClosure* soc) NOT_CDS_JAVA_HEAP_RETURN;
468
469 #ifndef PRODUCT
470 static bool is_a_test_class_in_unnamed_module(Klass* ik) NOT_CDS_JAVA_HEAP_RETURN_(false);
471 static void initialize_test_class_from_archive(TRAPS) NOT_CDS_JAVA_HEAP_RETURN;
472 #endif
473
474 static void add_to_permanent_oop_table(oop obj, int offset);
475
476 // AOT-compile time only: get a stable index for an archived object.
477 // Returns 0 if obj is not archived.
478 static int get_archived_object_permanent_index(oop obj) NOT_CDS_JAVA_HEAP_RETURN_(-1);
479 // Runtime only: get back the same object for an index returned by
480 // get_archived_object_permanent_index().
481 static oop get_archived_object(int permanent_index) NOT_CDS_JAVA_HEAP_RETURN_(nullptr);
482
483 static void initialize_java_lang_invoke(TRAPS) NOT_CDS_JAVA_HEAP_RETURN;
484 static void init_classes_for_special_subgraph(Handle loader, TRAPS) NOT_CDS_JAVA_HEAP_RETURN;
485
486 static bool is_lambda_form_klass(InstanceKlass* ik) NOT_CDS_JAVA_HEAP_RETURN_(false);
487 static bool is_lambda_proxy_klass(InstanceKlass* ik) NOT_CDS_JAVA_HEAP_RETURN_(false);
488 static bool is_string_concat_klass(InstanceKlass* ik) NOT_CDS_JAVA_HEAP_RETURN_(false);
489 static bool is_archivable_hidden_klass(InstanceKlass* ik) NOT_CDS_JAVA_HEAP_RETURN_(false);
490 };
491
492 class CachedCodeDirectoryInternal {
493 int _permanent_oop_count;
494 int* _permanent_oop_offsets; // offset of each permanent object from the bottom of the archived heap
495 public:
496 void dumptime_init_internal();
497 void runtime_init_internal();
498 };
499
500 #if INCLUDE_CDS_JAVA_HEAP
501 class DumpedInternedStrings :
502 public ResizeableResourceHashtable<oop, bool,
503 AnyObj::C_HEAP,
504 mtClassShared,
505 HeapShared::string_oop_hash>
506 {
507 public:
508 DumpedInternedStrings(unsigned size, unsigned max_size) :
509 ResizeableResourceHashtable<oop, bool,
510 AnyObj::C_HEAP,
511 mtClassShared,
512 HeapShared::string_oop_hash>(size, max_size) {}
513 };
514 #endif
515
516 #endif // SHARE_CDS_HEAPSHARED_HPP