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/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 // Can this VM write a heap region into the CDS archive?
147 static bool can_write() {
148 CDS_JAVA_HEAP_ONLY(
149 if (_disable_writing) {
150 return false;
151 }
152 // Need compressed class pointers for heap region dump.
153 if (!UseCompressedClassPointers) {
154 return false;
155 }
156 // Almost all GCs support heap region dump, except ZGC (so far).
157 return !UseZGC;
158 )
159 NOT_CDS_JAVA_HEAP(return false;)
160 }
161
162 static void disable_writing() {
163 CDS_JAVA_HEAP_ONLY(_disable_writing = true;)
164 }
165
166 static bool is_subgraph_root_class(InstanceKlass* ik);
167
168 // Scratch objects for archiving Klass::java_mirror()
169 static oop scratch_java_mirror(BasicType t) NOT_CDS_JAVA_HEAP_RETURN_(nullptr);
170 static oop scratch_java_mirror(Klass* k) NOT_CDS_JAVA_HEAP_RETURN_(nullptr);
171 static oop scratch_java_mirror(oop java_mirror) NOT_CDS_JAVA_HEAP_RETURN_(nullptr);
172 static bool is_archived_boot_layer_available(JavaThread* current) NOT_CDS_JAVA_HEAP_RETURN_(false);
173
174 // Look for all hidden classes that are referenced by archived objects.
175 static void start_finding_required_hidden_classes() NOT_CDS_JAVA_HEAP_RETURN;
176 static void find_required_hidden_classes_in_object(oop o) NOT_CDS_JAVA_HEAP_RETURN;
177 static void end_finding_required_hidden_classes() NOT_CDS_JAVA_HEAP_RETURN;
178
179 private:
180 #if INCLUDE_CDS_JAVA_HEAP
181 static bool _disable_writing;
182 static DumpedInternedStrings *_dumped_interned_strings;
183
184 // statistics
185 constexpr static int ALLOC_STAT_SLOTS = 16;
186 static size_t _alloc_count[ALLOC_STAT_SLOTS];
187 static size_t _alloc_size[ALLOC_STAT_SLOTS];
188 static size_t _total_obj_count;
189 static size_t _total_obj_size; // in HeapWords
190
191 static void count_allocation(size_t size);
192 static void print_stats();
193 static void debug_trace();
194 public:
195 static unsigned oop_hash(oop const& p);
196 static unsigned string_oop_hash(oop const& string) {
197 return java_lang_String::hash_code(string);
198 }
199
200 class CopyKlassSubGraphInfoToArchive;
201
202 class CachedOopInfo {
203 // Used by CDSHeapVerifier.
204 oop _orig_referrer;
205
206 // The location of this object inside ArchiveHeapWriter::_buffer
207 size_t _buffer_offset;
208
209 // One or more fields in this object are pointing to non-null oops.
210 bool _has_oop_pointers;
211
212 // One or more fields in this object are pointing to MetaspaceObj
213 bool _has_native_pointers;
214 public:
215 CachedOopInfo(oop orig_referrer, bool has_oop_pointers)
216 : _orig_referrer(orig_referrer),
217 _buffer_offset(0),
218 _has_oop_pointers(has_oop_pointers),
219 _has_native_pointers(false) {}
220 oop orig_referrer() const { return _orig_referrer; }
221 void set_buffer_offset(size_t offset) { _buffer_offset = offset; }
222 size_t buffer_offset() const { return _buffer_offset; }
223 bool has_oop_pointers() const { return _has_oop_pointers; }
224 bool has_native_pointers() const { return _has_native_pointers; }
225 void set_has_native_pointers() { _has_native_pointers = true; }
226 };
227
228 private:
229 static const int INITIAL_TABLE_SIZE = 15889; // prime number
230 static const int MAX_TABLE_SIZE = 1000000;
231 typedef ResizeableResourceHashtable<oop, CachedOopInfo,
232 AnyObj::C_HEAP,
233 mtClassShared,
234 HeapShared::oop_hash> ArchivedObjectCache;
235 static ArchivedObjectCache* _archived_object_cache;
236
237 class DumpTimeKlassSubGraphInfoTable
238 : public ResourceHashtable<Klass*, KlassSubGraphInfo,
239 137, // prime number
240 AnyObj::C_HEAP,
241 mtClassShared,
242 DumpTimeSharedClassTable_hash> {
243 public:
244 int _count;
245 };
246
247 public: // solaris compiler wants this for RunTimeKlassSubGraphInfoTable
248 inline static bool record_equals_compact_hashtable_entry(
249 const ArchivedKlassSubGraphInfoRecord* value, const Klass* key, int len_unused) {
250 return (value->klass() == key);
251 }
252
253 private:
254 typedef OffsetCompactHashtable<
255 const Klass*,
256 const ArchivedKlassSubGraphInfoRecord*,
257 record_equals_compact_hashtable_entry
258 > RunTimeKlassSubGraphInfoTable;
259
260 static DumpTimeKlassSubGraphInfoTable* _dump_time_subgraph_info_table;
261 static RunTimeKlassSubGraphInfoTable _run_time_subgraph_info_table;
262
263 class FindRequiredHiddenClassesOopClosure;
264 static void find_required_hidden_classes_helper(ArchivableStaticFieldInfo fields[]);
265
266 static CachedOopInfo make_cached_oop_info(oop obj);
267 static ArchivedKlassSubGraphInfoRecord* archive_subgraph_info(KlassSubGraphInfo* info);
268 static void archive_object_subgraphs(ArchivableStaticFieldInfo fields[],
269 bool is_full_module_graph);
270
271 // Archive object sub-graph starting from the given static field
272 // in Klass k's mirror.
273 static void archive_reachable_objects_from_static_field(
274 InstanceKlass* k, const char* klass_name,
275 int field_offset, const char* field_name);
276
277 static void verify_subgraph_from_static_field(
278 InstanceKlass* k, int field_offset) PRODUCT_RETURN;
279 static void verify_reachable_objects_from(oop obj) PRODUCT_RETURN;
280 static void verify_subgraph_from(oop orig_obj) PRODUCT_RETURN;
281 static void check_special_subgraph_classes();
282
283 static KlassSubGraphInfo* init_subgraph_info(Klass *k, bool is_full_module_graph);
284 static KlassSubGraphInfo* get_subgraph_info(Klass *k);
285
286 static void init_subgraph_entry_fields(TRAPS) NOT_CDS_JAVA_HEAP_RETURN;
287 static void init_subgraph_entry_fields(ArchivableStaticFieldInfo fields[], TRAPS);
288
289 // UseCompressedOops only: Used by decode_from_archive
290 static address _narrow_oop_base;
291 static int _narrow_oop_shift;
292
293 // !UseCompressedOops only: used to relocate pointers to the archived objects
294 static ptrdiff_t _runtime_delta;
295
296 typedef ResizeableResourceHashtable<oop, bool,
297 AnyObj::C_HEAP,
298 mtClassShared,
299 HeapShared::oop_hash> SeenObjectsTable;
300
301 static SeenObjectsTable *_seen_objects_table;
302
303 // The "special subgraph" contains all the archived objects that are reachable
304 // from the following roots:
305 // - interned strings
306 // - Klass::java_mirror() -- including aot-initialized mirrors such as those of Enum klasses.
307 // - ConstantPool::resolved_references()
308 // - Universe::<xxx>_exception_instance()
309 static KlassSubGraphInfo* _dump_time_special_subgraph; // for collecting info during dump time
310 static ArchivedKlassSubGraphInfoRecord* _run_time_special_subgraph; // for initializing classes during run time.
311
312 static GrowableArrayCHeap<oop, mtClassShared>* _pending_roots;
313 static GrowableArrayCHeap<OopHandle, mtClassShared>* _root_segments;
314 static int _root_segment_max_size_elems;
315 static OopHandle _scratch_basic_type_mirrors[T_VOID+1];
316 static MetaspaceObjToOopHandleTable* _scratch_java_mirror_table;
317 static MetaspaceObjToOopHandleTable* _scratch_references_table;
318
319 static void init_seen_objects_table() {
320 assert(_seen_objects_table == nullptr, "must be");
321 _seen_objects_table = new (mtClass)SeenObjectsTable(INITIAL_TABLE_SIZE, MAX_TABLE_SIZE);
322 }
323 static void delete_seen_objects_table() {
324 assert(_seen_objects_table != nullptr, "must be");
325 delete _seen_objects_table;
326 _seen_objects_table = nullptr;
327 }
328
329 // Statistics (for one round of start_recording_subgraph ... done_recording_subgraph)
330 static int _num_new_walked_objs;
331 static int _num_new_archived_objs;
332 static int _num_old_recorded_klasses;
333
334 // Statistics (for all archived subgraphs)
335 static int _num_total_subgraph_recordings;
336 static int _num_total_walked_objs;
337 static int _num_total_archived_objs;
338 static int _num_total_recorded_klasses;
339 static int _num_total_verifications;
340
341 static void start_recording_subgraph(InstanceKlass *k, const char* klass_name,
342 bool is_full_module_graph);
343 static void done_recording_subgraph(InstanceKlass *k, const char* klass_name);
344
345 static bool has_been_seen_during_subgraph_recording(oop obj);
346 static void set_has_been_seen_during_subgraph_recording(oop obj);
347 static bool archive_object(oop obj);
348 static void copy_aot_initialized_mirror(Klass* orig_k, oop orig_mirror, oop m);
349 static void copy_interned_strings();
350
351 static void resolve_classes_for_subgraphs(JavaThread* current, ArchivableStaticFieldInfo fields[]);
352 static void resolve_classes_for_subgraph_of(JavaThread* current, Klass* k);
353 static void clear_archived_roots_of(Klass* k);
354 static const ArchivedKlassSubGraphInfoRecord*
355 resolve_or_init_classes_for_subgraph_of(Klass* k, bool do_init, TRAPS);
356 static void resolve_or_init(const char* klass_name, bool do_init, TRAPS);
357 static void resolve_or_init(Klass* k, bool do_init, TRAPS);
358 static void init_archived_fields_for(Klass* k, const ArchivedKlassSubGraphInfoRecord* record);
359
360 static int init_loaded_regions(FileMapInfo* mapinfo, LoadedArchiveHeapRegion* loaded_regions,
361 MemRegion& archive_space);
362 static void sort_loaded_regions(LoadedArchiveHeapRegion* loaded_regions, int num_loaded_regions,
363 uintptr_t buffer);
364 static bool load_regions(FileMapInfo* mapinfo, LoadedArchiveHeapRegion* loaded_regions,
365 int num_loaded_regions, uintptr_t buffer);
366 static void init_loaded_heap_relocation(LoadedArchiveHeapRegion* reloc_info,
367 int num_loaded_regions);
368 static void fill_failed_loaded_region();
369 static void mark_native_pointers(oop orig_obj);
370 static bool has_been_archived(oop orig_obj);
371 static void prepare_resolved_references();
372 static void archive_java_mirrors();
373 static void archive_strings();
374 static void copy_special_subgraph();
375
376 class AOTInitializedClassScanner;
377 static void find_all_aot_initialized_classes();
378 static void find_all_aot_initialized_classes_helper();
379 static bool scan_for_aot_initialized_classes(oop obj);
380
381 public:
382 static void reset_archived_object_states(TRAPS);
383 static void create_archived_object_cache() {
384 _archived_object_cache =
385 new (mtClass)ArchivedObjectCache(INITIAL_TABLE_SIZE, MAX_TABLE_SIZE);
386 }
387 static void destroy_archived_object_cache() {
388 delete _archived_object_cache;
389 _archived_object_cache = nullptr;
390 }
391 static ArchivedObjectCache* archived_object_cache() {
392 return _archived_object_cache;
393 }
394
395 static int archive_exception_instance(oop exception);
396 static void archive_objects(ArchiveHeapInfo* heap_info);
397 static void copy_objects();
398
399 static bool archive_reachable_objects_from(int level,
400 KlassSubGraphInfo* subgraph_info,
401 oop orig_obj);
402
403 static void add_to_dumped_interned_strings(oop string);
404
405 // Scratch objects for archiving Klass::java_mirror()
406 static void set_scratch_java_mirror(Klass* k, oop mirror);
407 static void remove_scratch_objects(Klass* k);
408 static void get_pointer_info(oop src_obj, bool& has_oop_pointers, bool& has_native_pointers);
409 static void set_has_native_pointers(oop src_obj);
410
411 // We use the HeapShared::roots() array to make sure that objects stored in the
412 // archived heap region are not prematurely collected. These roots include:
413 //
414 // - mirrors of classes that have not yet been loaded.
415 // - ConstantPool::resolved_references() of classes that have not yet been loaded.
416 // - ArchivedKlassSubGraphInfoRecords that have not been initialized
417 // - java.lang.Module objects that have not yet been added to the module graph
418 //
419 // When a mirror M becomes referenced by a newly loaded class K, M will be removed
420 // from HeapShared::roots() via clear_root(), and K will be responsible for
421 // keeping M alive.
422 //
423 // Other types of roots are also cleared similarly when they become referenced.
424
425 // Dump-time only. Returns the index of the root, which can be used at run time to read
426 // the root using get_root(index, ...).
427 static int append_root(oop obj);
428 static GrowableArrayCHeap<oop, mtClassShared>* pending_roots() { return _pending_roots; }
429
430 // Dump-time and runtime
431 static objArrayOop root_segment(int segment_idx);
432 static oop get_root(int index, bool clear=false);
433
434 // Run-time only
435 static void clear_root(int index);
436
437 static void get_segment_indexes(int index, int& segment_index, int& internal_index);
438
439 static void setup_test_class(const char* test_class_name) PRODUCT_RETURN;
440 #endif // INCLUDE_CDS_JAVA_HEAP
441
442 public:
443 static objArrayOop scratch_resolved_references(ConstantPool* src);
444 static void add_scratch_resolved_references(ConstantPool* src, objArrayOop dest) NOT_CDS_JAVA_HEAP_RETURN;
445 static void init_scratch_objects(TRAPS) NOT_CDS_JAVA_HEAP_RETURN;
446 static void init_box_classes(TRAPS) NOT_CDS_JAVA_HEAP_RETURN;
447 static bool is_heap_region(int idx) {
448 CDS_JAVA_HEAP_ONLY(return (idx == MetaspaceShared::hp);)
449 NOT_CDS_JAVA_HEAP_RETURN_(false);
450 }
451
452 static void resolve_classes(JavaThread* current) NOT_CDS_JAVA_HEAP_RETURN;
453 static void initialize_from_archived_subgraph(JavaThread* current, Klass* k) NOT_CDS_JAVA_HEAP_RETURN;
454
455 static void init_for_dumping(TRAPS) NOT_CDS_JAVA_HEAP_RETURN;
456 static void write_subgraph_info_table() NOT_CDS_JAVA_HEAP_RETURN;
457 static void add_root_segment(objArrayOop segment_oop) NOT_CDS_JAVA_HEAP_RETURN;
458 static void init_root_segment_sizes(int max_size_elems) NOT_CDS_JAVA_HEAP_RETURN;
459 static void serialize_tables(SerializeClosure* soc) NOT_CDS_JAVA_HEAP_RETURN;
460
461 #ifndef PRODUCT
462 static bool is_a_test_class_in_unnamed_module(Klass* ik) NOT_CDS_JAVA_HEAP_RETURN_(false);
463 static void initialize_test_class_from_archive(TRAPS) NOT_CDS_JAVA_HEAP_RETURN;
464 #endif
465
466 static void initialize_java_lang_invoke(TRAPS) NOT_CDS_JAVA_HEAP_RETURN;
467 static void init_classes_for_special_subgraph(Handle loader, TRAPS) NOT_CDS_JAVA_HEAP_RETURN;
468
469 static bool is_lambda_form_klass(InstanceKlass* ik) NOT_CDS_JAVA_HEAP_RETURN_(false);
470 static bool is_lambda_proxy_klass(InstanceKlass* ik) NOT_CDS_JAVA_HEAP_RETURN_(false);
471 static bool is_string_concat_klass(InstanceKlass* ik) NOT_CDS_JAVA_HEAP_RETURN_(false);
472 static bool is_archivable_hidden_klass(InstanceKlass* ik) NOT_CDS_JAVA_HEAP_RETURN_(false);
473 };
474
475 #if INCLUDE_CDS_JAVA_HEAP
476 class DumpedInternedStrings :
477 public ResizeableResourceHashtable<oop, bool,
478 AnyObj::C_HEAP,
479 mtClassShared,
480 HeapShared::string_oop_hash>
481 {
482 public:
483 DumpedInternedStrings(unsigned size, unsigned max_size) :
484 ResizeableResourceHashtable<oop, bool,
485 AnyObj::C_HEAP,
486 mtClassShared,
487 HeapShared::string_oop_hash>(size, max_size) {}
488 };
489 #endif
490
491 #endif // SHARE_CDS_HEAPSHARED_HPP