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 #include "precompiled.hpp"
26 #include "cds/archiveBuilder.hpp"
27 #include "cds/archiveHeapLoader.hpp"
28 #include "cds/archiveHeapWriter.hpp"
29 #include "cds/archiveUtils.hpp"
30 #include "cds/cdsConfig.hpp"
31 #include "cds/cdsEnumKlass.hpp"
32 #include "cds/cdsHeapVerifier.hpp"
33 #include "cds/heapShared.hpp"
34 #include "cds/metaspaceShared.hpp"
35 #include "classfile/classLoaderData.hpp"
36 #include "classfile/javaClasses.inline.hpp"
37 #include "classfile/modules.hpp"
38 #include "classfile/stringTable.hpp"
39 #include "classfile/symbolTable.hpp"
40 #include "classfile/systemDictionary.hpp"
41 #include "classfile/systemDictionaryShared.hpp"
42 #include "classfile/vmClasses.hpp"
43 #include "classfile/vmSymbols.hpp"
44 #include "gc/shared/collectedHeap.hpp"
45 #include "gc/shared/gcLocker.hpp"
46 #include "gc/shared/gcVMOperations.hpp"
47 #include "logging/log.hpp"
48 #include "logging/logStream.hpp"
49 #include "memory/iterator.inline.hpp"
50 #include "memory/resourceArea.hpp"
51 #include "memory/universe.hpp"
52 #include "oops/compressedOops.inline.hpp"
53 #include "oops/fieldStreams.inline.hpp"
54 #include "oops/objArrayOop.inline.hpp"
55 #include "oops/oop.inline.hpp"
56 #include "oops/typeArrayOop.inline.hpp"
57 #include "prims/jvmtiExport.hpp"
58 #include "runtime/fieldDescriptor.inline.hpp"
59 #include "runtime/init.hpp"
60 #include "runtime/javaCalls.hpp"
61 #include "runtime/mutexLocker.hpp"
62 #include "runtime/safepointVerifiers.hpp"
63 #include "utilities/bitMap.inline.hpp"
64 #include "utilities/copy.hpp"
65 #if INCLUDE_G1GC
66 #include "gc/g1/g1CollectedHeap.hpp"
67 #endif
68
69 #if INCLUDE_CDS_JAVA_HEAP
70
71 struct ArchivableStaticFieldInfo {
72 const char* klass_name;
73 const char* field_name;
74 InstanceKlass* klass;
75 int offset;
76 BasicType type;
77
78 ArchivableStaticFieldInfo(const char* k, const char* f)
79 : klass_name(k), field_name(f), klass(nullptr), offset(0), type(T_ILLEGAL) {}
80
81 bool valid() {
82 return klass_name != nullptr;
83 }
84 };
85
86 bool HeapShared::_disable_writing = false;
87 DumpedInternedStrings *HeapShared::_dumped_interned_strings = nullptr;
88
89 size_t HeapShared::_alloc_count[HeapShared::ALLOC_STAT_SLOTS];
90 size_t HeapShared::_alloc_size[HeapShared::ALLOC_STAT_SLOTS];
91 size_t HeapShared::_total_obj_count;
92 size_t HeapShared::_total_obj_size;
93
94 #ifndef PRODUCT
95 #define ARCHIVE_TEST_FIELD_NAME "archivedObjects"
96 static Array<char>* _archived_ArchiveHeapTestClass = nullptr;
97 static const char* _test_class_name = nullptr;
98 static const Klass* _test_class = nullptr;
99 static const ArchivedKlassSubGraphInfoRecord* _test_class_record = nullptr;
100 #endif
101
102
103 //
104 // If you add new entries to the following tables, you should know what you're doing!
105 //
106
107 static ArchivableStaticFieldInfo archive_subgraph_entry_fields[] = {
108 {"java/lang/Integer$IntegerCache", "archivedCache"},
109 {"java/lang/Long$LongCache", "archivedCache"},
110 {"java/lang/Byte$ByteCache", "archivedCache"},
111 {"java/lang/Short$ShortCache", "archivedCache"},
112 {"java/lang/Character$CharacterCache", "archivedCache"},
113 {"java/util/jar/Attributes$Name", "KNOWN_NAMES"},
114 {"sun/util/locale/BaseLocale", "constantBaseLocales"},
115 {"jdk/internal/module/ArchivedModuleGraph", "archivedModuleGraph"},
116 {"java/util/ImmutableCollections", "archivedObjects"},
117 {"java/lang/ModuleLayer", "EMPTY_LAYER"},
118 {"java/lang/module/Configuration", "EMPTY_CONFIGURATION"},
119 {"jdk/internal/math/FDBigInteger", "archivedCaches"},
120 #ifndef PRODUCT
121 {nullptr, nullptr}, // Extra slot for -XX:ArchiveHeapTestClass
122 #endif
123 {nullptr, nullptr},
124 };
125
126 // full module graph
127 static ArchivableStaticFieldInfo fmg_archive_subgraph_entry_fields[] = {
128 {"jdk/internal/loader/ArchivedClassLoaders", "archivedClassLoaders"},
129 {ARCHIVED_BOOT_LAYER_CLASS, ARCHIVED_BOOT_LAYER_FIELD},
130 {"java/lang/Module$ArchivedData", "archivedData"},
131 {nullptr, nullptr},
132 };
133
134 KlassSubGraphInfo* HeapShared::_default_subgraph_info;
135 GrowableArrayCHeap<oop, mtClassShared>* HeapShared::_pending_roots = nullptr;
136 OopHandle HeapShared::_roots;
137 OopHandle HeapShared::_scratch_basic_type_mirrors[T_VOID+1];
138 MetaspaceObjToOopHandleTable* HeapShared::_scratch_java_mirror_table = nullptr;
139 MetaspaceObjToOopHandleTable* HeapShared::_scratch_references_table = nullptr;
140
141 static bool is_subgraph_root_class_of(ArchivableStaticFieldInfo fields[], InstanceKlass* ik) {
142 for (int i = 0; fields[i].valid(); i++) {
143 if (fields[i].klass == ik) {
144 return true;
145 }
146 }
147 return false;
148 }
149
150 bool HeapShared::is_subgraph_root_class(InstanceKlass* ik) {
151 return is_subgraph_root_class_of(archive_subgraph_entry_fields, ik) ||
152 is_subgraph_root_class_of(fmg_archive_subgraph_entry_fields, ik);
153 }
154
155 unsigned HeapShared::oop_hash(oop const& p) {
156 // Do not call p->identity_hash() as that will update the
157 // object header.
158 return primitive_hash(cast_from_oop<intptr_t>(p));
159 }
160
161 static void reset_states(oop obj, TRAPS) {
162 Handle h_obj(THREAD, obj);
163 InstanceKlass* klass = InstanceKlass::cast(obj->klass());
164 TempNewSymbol method_name = SymbolTable::new_symbol("resetArchivedStates");
165 Symbol* method_sig = vmSymbols::void_method_signature();
166
167 while (klass != nullptr) {
168 Method* method = klass->find_method(method_name, method_sig);
169 if (method != nullptr) {
170 assert(method->is_private(), "must be");
171 if (log_is_enabled(Debug, cds)) {
172 ResourceMark rm(THREAD);
173 log_debug(cds)(" calling %s", method->name_and_sig_as_C_string());
174 }
175 JavaValue result(T_VOID);
176 JavaCalls::call_special(&result, h_obj, klass,
177 method_name, method_sig, CHECK);
178 }
179 klass = klass->java_super();
180 }
181 }
182
183 void HeapShared::reset_archived_object_states(TRAPS) {
184 assert(CDSConfig::is_dumping_heap(), "dump-time only");
185 log_debug(cds)("Resetting platform loader");
186 reset_states(SystemDictionary::java_platform_loader(), CHECK);
187 log_debug(cds)("Resetting system loader");
188 reset_states(SystemDictionary::java_system_loader(), CHECK);
189
190 // Clean up jdk.internal.loader.ClassLoaders::bootLoader(), which is not
191 // directly used for class loading, but rather is used by the core library
192 // to keep track of resources, etc, loaded by the null class loader.
193 //
194 // Note, this object is non-null, and is not the same as
195 // ClassLoaderData::the_null_class_loader_data()->class_loader(),
196 // which is null.
197 log_debug(cds)("Resetting boot loader");
198 JavaValue result(T_OBJECT);
199 JavaCalls::call_static(&result,
200 vmClasses::jdk_internal_loader_ClassLoaders_klass(),
201 vmSymbols::bootLoader_name(),
202 vmSymbols::void_BuiltinClassLoader_signature(),
203 CHECK);
204 Handle boot_loader(THREAD, result.get_oop());
205 reset_states(boot_loader(), CHECK);
206 }
207
208 HeapShared::ArchivedObjectCache* HeapShared::_archived_object_cache = nullptr;
209
210 bool HeapShared::has_been_archived(oop obj) {
211 assert(CDSConfig::is_dumping_heap(), "dump-time only");
212 return archived_object_cache()->get(obj) != nullptr;
213 }
214
215 int HeapShared::append_root(oop obj) {
216 assert(CDSConfig::is_dumping_heap(), "dump-time only");
217
218 // No GC should happen since we aren't scanning _pending_roots.
219 assert(Thread::current() == (Thread*)VMThread::vm_thread(), "should be in vm thread");
220
221 if (_pending_roots == nullptr) {
222 _pending_roots = new GrowableArrayCHeap<oop, mtClassShared>(500);
223 }
224
225 return _pending_roots->append(obj);
226 }
227
228 objArrayOop HeapShared::roots() {
229 if (CDSConfig::is_dumping_heap()) {
230 assert(Thread::current() == (Thread*)VMThread::vm_thread(), "should be in vm thread");
231 if (!HeapShared::can_write()) {
232 return nullptr;
233 }
234 } else {
235 assert(CDSConfig::is_using_archive(), "must be");
236 }
237
238 objArrayOop roots = (objArrayOop)_roots.resolve();
239 assert(roots != nullptr, "should have been initialized");
240 return roots;
241 }
242
243 // Returns an objArray that contains all the roots of the archived objects
244 oop HeapShared::get_root(int index, bool clear) {
245 assert(index >= 0, "sanity");
246 assert(!CDSConfig::is_dumping_heap() && CDSConfig::is_using_archive(), "runtime only");
247 assert(!_roots.is_empty(), "must have loaded shared heap");
248 oop result = roots()->obj_at(index);
249 if (clear) {
250 clear_root(index);
251 }
252 return result;
253 }
254
255 void HeapShared::clear_root(int index) {
256 assert(index >= 0, "sanity");
257 assert(CDSConfig::is_using_archive(), "must be");
258 if (ArchiveHeapLoader::is_in_use()) {
259 if (log_is_enabled(Debug, cds, heap)) {
260 oop old = roots()->obj_at(index);
261 log_debug(cds, heap)("Clearing root %d: was " PTR_FORMAT, index, p2i(old));
262 }
263 roots()->obj_at_put(index, nullptr);
264 }
265 }
266
267 bool HeapShared::archive_object(oop obj) {
268 assert(CDSConfig::is_dumping_heap(), "dump-time only");
269
270 assert(!obj->is_stackChunk(), "do not archive stack chunks");
271 if (has_been_archived(obj)) {
272 return true;
273 }
274
275 if (ArchiveHeapWriter::is_too_large_to_archive(obj->size())) {
276 log_debug(cds, heap)("Cannot archive, object (" PTR_FORMAT ") is too large: " SIZE_FORMAT,
277 p2i(obj), obj->size());
278 return false;
279 } else {
280 count_allocation(obj->size());
281 ArchiveHeapWriter::add_source_obj(obj);
282 CachedOopInfo info = make_cached_oop_info(obj);
283 archived_object_cache()->put_when_absent(obj, info);
284 archived_object_cache()->maybe_grow();
285 mark_native_pointers(obj);
286
287 if (log_is_enabled(Debug, cds, heap)) {
288 ResourceMark rm;
289 log_debug(cds, heap)("Archived heap object " PTR_FORMAT " : %s",
290 p2i(obj), obj->klass()->external_name());
291 }
292
293 if (java_lang_Module::is_instance(obj) && Modules::check_archived_module_oop(obj)) {
294 Modules::update_oops_in_archived_module(obj, append_root(obj));
295 }
296
297 return true;
298 }
299 }
300
301 class MetaspaceObjToOopHandleTable: public ResourceHashtable<MetaspaceObj*, OopHandle,
302 36137, // prime number
303 AnyObj::C_HEAP,
304 mtClassShared> {
305 public:
306 oop get_oop(MetaspaceObj* ptr) {
307 MutexLocker ml(ScratchObjects_lock, Mutex::_no_safepoint_check_flag);
308 OopHandle* handle = get(ptr);
309 if (handle != nullptr) {
310 return handle->resolve();
311 } else {
312 return nullptr;
313 }
314 }
315 void set_oop(MetaspaceObj* ptr, oop o) {
316 MutexLocker ml(ScratchObjects_lock, Mutex::_no_safepoint_check_flag);
317 OopHandle handle(Universe::vm_global(), o);
318 bool is_new = put(ptr, handle);
319 assert(is_new, "cannot set twice");
320 }
321 void remove_oop(MetaspaceObj* ptr) {
322 MutexLocker ml(ScratchObjects_lock, Mutex::_no_safepoint_check_flag);
323 OopHandle* handle = get(ptr);
324 if (handle != nullptr) {
325 handle->release(Universe::vm_global());
326 remove(ptr);
327 }
328 }
329 };
330
331 void HeapShared::add_scratch_resolved_references(ConstantPool* src, objArrayOop dest) {
332 _scratch_references_table->set_oop(src, dest);
333 }
334
335 objArrayOop HeapShared::scratch_resolved_references(ConstantPool* src) {
336 return (objArrayOop)_scratch_references_table->get_oop(src);
337 }
338
339 void HeapShared::init_scratch_objects(TRAPS) {
340 for (int i = T_BOOLEAN; i < T_VOID+1; i++) {
341 BasicType bt = (BasicType)i;
342 if (!is_reference_type(bt)) {
343 oop m = java_lang_Class::create_basic_type_mirror(type2name(bt), bt, CHECK);
344 _scratch_basic_type_mirrors[i] = OopHandle(Universe::vm_global(), m);
345 }
346 }
347 _scratch_java_mirror_table = new (mtClass)MetaspaceObjToOopHandleTable();
348 _scratch_references_table = new (mtClass)MetaspaceObjToOopHandleTable();
349 }
350
351 oop HeapShared::scratch_java_mirror(BasicType t) {
352 assert((uint)t < T_VOID+1, "range check");
353 assert(!is_reference_type(t), "sanity");
354 return _scratch_basic_type_mirrors[t].resolve();
355 }
356
357 oop HeapShared::scratch_java_mirror(Klass* k) {
358 return _scratch_java_mirror_table->get_oop(k);
359 }
360
361 void HeapShared::set_scratch_java_mirror(Klass* k, oop mirror) {
362 _scratch_java_mirror_table->set_oop(k, mirror);
363 }
364
365 void HeapShared::remove_scratch_objects(Klass* k) {
366 _scratch_java_mirror_table->remove_oop(k);
367 if (k->is_instance_klass()) {
368 _scratch_references_table->remove(InstanceKlass::cast(k)->constants());
369 }
370 }
371
372 void HeapShared::archive_java_mirrors() {
373 for (int i = T_BOOLEAN; i < T_VOID+1; i++) {
374 BasicType bt = (BasicType)i;
375 if (!is_reference_type(bt)) {
376 oop m = _scratch_basic_type_mirrors[i].resolve();
377 assert(m != nullptr, "sanity");
378 bool success = archive_reachable_objects_from(1, _default_subgraph_info, m);
379 assert(success, "sanity");
380
381 log_trace(cds, heap, mirror)(
382 "Archived %s mirror object from " PTR_FORMAT,
383 type2name(bt), p2i(m));
384
385 Universe::set_archived_basic_type_mirror_index(bt, append_root(m));
386 }
387 }
388
389 GrowableArray<Klass*>* klasses = ArchiveBuilder::current()->klasses();
390 assert(klasses != nullptr, "sanity");
391 for (int i = 0; i < klasses->length(); i++) {
392 Klass* orig_k = klasses->at(i);
393 oop m = scratch_java_mirror(orig_k);
394 if (m != nullptr) {
395 Klass* buffered_k = ArchiveBuilder::get_buffered_klass(orig_k);
396 bool success = archive_reachable_objects_from(1, _default_subgraph_info, m);
397 guarantee(success, "scratch mirrors must point to only archivable objects");
398 buffered_k->set_archived_java_mirror(append_root(m));
399 ResourceMark rm;
400 log_trace(cds, heap, mirror)(
401 "Archived %s mirror object from " PTR_FORMAT,
402 buffered_k->external_name(), p2i(m));
403
404 // archive the resolved_referenes array
405 if (buffered_k->is_instance_klass()) {
406 InstanceKlass* ik = InstanceKlass::cast(buffered_k);
407 oop rr = ik->constants()->prepare_resolved_references_for_archiving();
408 if (rr != nullptr && !ArchiveHeapWriter::is_too_large_to_archive(rr)) {
409 bool success = HeapShared::archive_reachable_objects_from(1, _default_subgraph_info, rr);
410 assert(success, "must be");
411 int root_index = append_root(rr);
412 ik->constants()->cache()->set_archived_references(root_index);
413 }
414 }
415 }
416 }
417 }
418
419 void HeapShared::archive_strings() {
420 oop shared_strings_array = StringTable::init_shared_table(_dumped_interned_strings);
421 bool success = archive_reachable_objects_from(1, _default_subgraph_info, shared_strings_array);
422 // We must succeed because:
423 // - _dumped_interned_strings do not contain any large strings.
424 // - StringTable::init_shared_table() doesn't create any large arrays.
425 assert(success, "shared strings array must not point to arrays or strings that are too large to archive");
426 StringTable::set_shared_strings_array_index(append_root(shared_strings_array));
427 }
428
429 int HeapShared::archive_exception_instance(oop exception) {
430 bool success = archive_reachable_objects_from(1, _default_subgraph_info, exception);
431 assert(success, "sanity");
432 return append_root(exception);
433 }
434
435 void HeapShared::mark_native_pointers(oop orig_obj) {
436 if (java_lang_Class::is_instance(orig_obj)) {
437 ArchiveHeapWriter::mark_native_pointer(orig_obj, java_lang_Class::klass_offset());
438 ArchiveHeapWriter::mark_native_pointer(orig_obj, java_lang_Class::array_klass_offset());
439 }
440 }
441
442 void HeapShared::get_pointer_info(oop src_obj, bool& has_oop_pointers, bool& has_native_pointers) {
443 CachedOopInfo* info = archived_object_cache()->get(src_obj);
444 assert(info != nullptr, "must be");
445 has_oop_pointers = info->has_oop_pointers();
446 has_native_pointers = info->has_native_pointers();
447 }
448
449 void HeapShared::set_has_native_pointers(oop src_obj) {
450 CachedOopInfo* info = archived_object_cache()->get(src_obj);
451 assert(info != nullptr, "must be");
452 info->set_has_native_pointers();
453 }
454
455 void HeapShared::archive_objects(ArchiveHeapInfo *heap_info) {
456 {
457 NoSafepointVerifier nsv;
458
459 _default_subgraph_info = init_subgraph_info(vmClasses::Object_klass(), false);
460
461 // Cache for recording where the archived objects are copied to
462 create_archived_object_cache();
463
464 log_info(cds)("Heap range = [" PTR_FORMAT " - " PTR_FORMAT "]",
465 UseCompressedOops ? p2i(CompressedOops::begin()) :
466 p2i((address)G1CollectedHeap::heap()->reserved().start()),
467 UseCompressedOops ? p2i(CompressedOops::end()) :
468 p2i((address)G1CollectedHeap::heap()->reserved().end()));
469 copy_objects();
470
471 CDSHeapVerifier::verify();
472 check_default_subgraph_classes();
473 }
474
475 ArchiveHeapWriter::write(_pending_roots, heap_info);
476 }
477
478 void HeapShared::copy_interned_strings() {
479 init_seen_objects_table();
480
481 auto copier = [&] (oop s, bool value_ignored) {
482 assert(s != nullptr, "sanity");
483 assert(!ArchiveHeapWriter::is_string_too_large_to_archive(s), "large strings must have been filtered");
484 bool success = archive_reachable_objects_from(1, _default_subgraph_info, s);
485 assert(success, "must be");
486 // Prevent string deduplication from changing the value field to
487 // something not in the archive.
488 java_lang_String::set_deduplication_forbidden(s);
489 };
490 _dumped_interned_strings->iterate_all(copier);
491
492 delete_seen_objects_table();
493 }
494
495 void HeapShared::copy_special_objects() {
496 // Archive special objects that do not belong to any subgraphs
497 init_seen_objects_table();
498 archive_java_mirrors();
499 archive_strings();
500 Universe::archive_exception_instances();
501 delete_seen_objects_table();
502 }
503
504 void HeapShared::copy_objects() {
505 assert(HeapShared::can_write(), "must be");
506
507 copy_interned_strings();
508 copy_special_objects();
509
510 archive_object_subgraphs(archive_subgraph_entry_fields,
511 false /* is_full_module_graph */);
512
513 if (CDSConfig::is_dumping_full_module_graph()) {
514 archive_object_subgraphs(fmg_archive_subgraph_entry_fields,
515 true /* is_full_module_graph */);
516 Modules::verify_archived_modules();
517 }
518 }
519
520 //
521 // Subgraph archiving support
522 //
523 HeapShared::DumpTimeKlassSubGraphInfoTable* HeapShared::_dump_time_subgraph_info_table = nullptr;
524 HeapShared::RunTimeKlassSubGraphInfoTable HeapShared::_run_time_subgraph_info_table;
525
526 // Get the subgraph_info for Klass k. A new subgraph_info is created if
527 // there is no existing one for k. The subgraph_info records the "buffered"
528 // address of the class.
529 KlassSubGraphInfo* HeapShared::init_subgraph_info(Klass* k, bool is_full_module_graph) {
530 assert(CDSConfig::is_dumping_heap(), "dump time only");
531 bool created;
532 Klass* buffered_k = ArchiveBuilder::get_buffered_klass(k);
533 KlassSubGraphInfo* info =
534 _dump_time_subgraph_info_table->put_if_absent(k, KlassSubGraphInfo(buffered_k, is_full_module_graph),
535 &created);
536 assert(created, "must not initialize twice");
537 return info;
538 }
539
540 KlassSubGraphInfo* HeapShared::get_subgraph_info(Klass* k) {
541 assert(CDSConfig::is_dumping_heap(), "dump time only");
542 KlassSubGraphInfo* info = _dump_time_subgraph_info_table->get(k);
543 assert(info != nullptr, "must have been initialized");
544 return info;
545 }
546
547 // Add an entry field to the current KlassSubGraphInfo.
548 void KlassSubGraphInfo::add_subgraph_entry_field(int static_field_offset, oop v) {
549 assert(CDSConfig::is_dumping_heap(), "dump time only");
550 if (_subgraph_entry_fields == nullptr) {
551 _subgraph_entry_fields =
552 new (mtClass) GrowableArray<int>(10, mtClass);
553 }
554 _subgraph_entry_fields->append(static_field_offset);
555 _subgraph_entry_fields->append(HeapShared::append_root(v));
556 }
557
558 // Add the Klass* for an object in the current KlassSubGraphInfo's subgraphs.
559 // Only objects of boot classes can be included in sub-graph.
560 void KlassSubGraphInfo::add_subgraph_object_klass(Klass* orig_k) {
561 assert(CDSConfig::is_dumping_heap(), "dump time only");
562 Klass* buffered_k = ArchiveBuilder::get_buffered_klass(orig_k);
563
564 if (_subgraph_object_klasses == nullptr) {
565 _subgraph_object_klasses =
566 new (mtClass) GrowableArray<Klass*>(50, mtClass);
567 }
568
569 assert(ArchiveBuilder::current()->is_in_buffer_space(buffered_k), "must be a shared class");
570
571 if (_k == buffered_k) {
572 // Don't add the Klass containing the sub-graph to it's own klass
573 // initialization list.
574 return;
575 }
576
577 if (buffered_k->is_instance_klass()) {
578 assert(InstanceKlass::cast(buffered_k)->is_shared_boot_class(),
579 "must be boot class");
580 // vmClasses::xxx_klass() are not updated, need to check
581 // the original Klass*
582 if (orig_k == vmClasses::String_klass() ||
583 orig_k == vmClasses::Object_klass()) {
584 // Initialized early during VM initialization. No need to be added
585 // to the sub-graph object class list.
586 return;
587 }
588 check_allowed_klass(InstanceKlass::cast(orig_k));
589 } else if (buffered_k->is_objArray_klass()) {
590 Klass* abk = ObjArrayKlass::cast(buffered_k)->bottom_klass();
591 if (abk->is_instance_klass()) {
592 assert(InstanceKlass::cast(abk)->is_shared_boot_class(),
593 "must be boot class");
594 check_allowed_klass(InstanceKlass::cast(ObjArrayKlass::cast(orig_k)->bottom_klass()));
595 }
596 if (buffered_k == Universe::objectArrayKlass()) {
597 // Initialized early during Universe::genesis. No need to be added
598 // to the list.
599 return;
600 }
601 } else {
602 assert(buffered_k->is_typeArray_klass(), "must be");
603 // Primitive type arrays are created early during Universe::genesis.
604 return;
605 }
606
607 if (log_is_enabled(Debug, cds, heap)) {
608 if (!_subgraph_object_klasses->contains(buffered_k)) {
609 ResourceMark rm;
610 log_debug(cds, heap)("Adding klass %s", orig_k->external_name());
611 }
612 }
613
614 _subgraph_object_klasses->append_if_missing(buffered_k);
615 _has_non_early_klasses |= is_non_early_klass(orig_k);
616 }
617
618 void KlassSubGraphInfo::check_allowed_klass(InstanceKlass* ik) {
619 if (ik->module()->name() == vmSymbols::java_base()) {
620 assert(ik->package() != nullptr, "classes in java.base cannot be in unnamed package");
621 return;
622 }
623
624 #ifndef PRODUCT
625 if (!ik->module()->is_named() && ik->package() == nullptr) {
626 // This class is loaded by ArchiveHeapTestClass
627 return;
628 }
629 const char* extra_msg = ", or in an unnamed package of an unnamed module";
630 #else
631 const char* extra_msg = "";
632 #endif
633
634 ResourceMark rm;
635 log_error(cds, heap)("Class %s not allowed in archive heap. Must be in java.base%s",
636 ik->external_name(), extra_msg);
637 MetaspaceShared::unrecoverable_writing_error();
638 }
639
640 bool KlassSubGraphInfo::is_non_early_klass(Klass* k) {
641 if (k->is_objArray_klass()) {
642 k = ObjArrayKlass::cast(k)->bottom_klass();
643 }
644 if (k->is_instance_klass()) {
645 if (!SystemDictionaryShared::is_early_klass(InstanceKlass::cast(k))) {
646 ResourceMark rm;
647 log_info(cds, heap)("non-early: %s", k->external_name());
648 return true;
649 } else {
650 return false;
651 }
652 } else {
653 return false;
654 }
655 }
656
657 // Initialize an archived subgraph_info_record from the given KlassSubGraphInfo.
658 void ArchivedKlassSubGraphInfoRecord::init(KlassSubGraphInfo* info) {
659 _k = info->klass();
660 _entry_field_records = nullptr;
661 _subgraph_object_klasses = nullptr;
662 _is_full_module_graph = info->is_full_module_graph();
663
664 if (_is_full_module_graph) {
665 // Consider all classes referenced by the full module graph as early -- we will be
666 // allocating objects of these classes during JVMTI early phase, so they cannot
667 // be processed by (non-early) JVMTI ClassFileLoadHook
668 _has_non_early_klasses = false;
669 } else {
670 _has_non_early_klasses = info->has_non_early_klasses();
671 }
672
673 if (_has_non_early_klasses) {
674 ResourceMark rm;
675 log_info(cds, heap)(
676 "Subgraph of klass %s has non-early klasses and cannot be used when JVMTI ClassFileLoadHook is enabled",
677 _k->external_name());
678 }
679
680 // populate the entry fields
681 GrowableArray<int>* entry_fields = info->subgraph_entry_fields();
682 if (entry_fields != nullptr) {
683 int num_entry_fields = entry_fields->length();
684 assert(num_entry_fields % 2 == 0, "sanity");
685 _entry_field_records =
686 ArchiveBuilder::new_ro_array<int>(num_entry_fields);
687 for (int i = 0 ; i < num_entry_fields; i++) {
688 _entry_field_records->at_put(i, entry_fields->at(i));
689 }
690 }
691
692 // the Klasses of the objects in the sub-graphs
693 GrowableArray<Klass*>* subgraph_object_klasses = info->subgraph_object_klasses();
694 if (subgraph_object_klasses != nullptr) {
695 int num_subgraphs_klasses = subgraph_object_klasses->length();
696 _subgraph_object_klasses =
697 ArchiveBuilder::new_ro_array<Klass*>(num_subgraphs_klasses);
698 for (int i = 0; i < num_subgraphs_klasses; i++) {
699 Klass* subgraph_k = subgraph_object_klasses->at(i);
700 if (log_is_enabled(Info, cds, heap)) {
701 ResourceMark rm;
702 log_info(cds, heap)(
703 "Archived object klass %s (%2d) => %s",
704 _k->external_name(), i, subgraph_k->external_name());
705 }
706 _subgraph_object_klasses->at_put(i, subgraph_k);
707 ArchivePtrMarker::mark_pointer(_subgraph_object_klasses->adr_at(i));
708 }
709 }
710
711 ArchivePtrMarker::mark_pointer(&_k);
712 ArchivePtrMarker::mark_pointer(&_entry_field_records);
713 ArchivePtrMarker::mark_pointer(&_subgraph_object_klasses);
714 }
715
716 struct CopyKlassSubGraphInfoToArchive : StackObj {
717 CompactHashtableWriter* _writer;
718 CopyKlassSubGraphInfoToArchive(CompactHashtableWriter* writer) : _writer(writer) {}
719
720 bool do_entry(Klass* klass, KlassSubGraphInfo& info) {
721 if (info.subgraph_object_klasses() != nullptr || info.subgraph_entry_fields() != nullptr) {
722 ArchivedKlassSubGraphInfoRecord* record =
723 (ArchivedKlassSubGraphInfoRecord*)ArchiveBuilder::ro_region_alloc(sizeof(ArchivedKlassSubGraphInfoRecord));
724 record->init(&info);
725
726 Klass* buffered_k = ArchiveBuilder::get_buffered_klass(klass);
727 unsigned int hash = SystemDictionaryShared::hash_for_shared_dictionary((address)buffered_k);
728 u4 delta = ArchiveBuilder::current()->any_to_offset_u4(record);
729 _writer->add(hash, delta);
730 }
731 return true; // keep on iterating
732 }
733 };
734
735 // Build the records of archived subgraph infos, which include:
736 // - Entry points to all subgraphs from the containing class mirror. The entry
737 // points are static fields in the mirror. For each entry point, the field
738 // offset, and value are recorded in the sub-graph
739 // info. The value is stored back to the corresponding field at runtime.
740 // - A list of klasses that need to be loaded/initialized before archived
741 // java object sub-graph can be accessed at runtime.
742 void HeapShared::write_subgraph_info_table() {
743 // Allocate the contents of the hashtable(s) inside the RO region of the CDS archive.
744 DumpTimeKlassSubGraphInfoTable* d_table = _dump_time_subgraph_info_table;
745 CompactHashtableStats stats;
746
747 _run_time_subgraph_info_table.reset();
748
749 CompactHashtableWriter writer(d_table->_count, &stats);
750 CopyKlassSubGraphInfoToArchive copy(&writer);
751 d_table->iterate(©);
752 writer.dump(&_run_time_subgraph_info_table, "subgraphs");
753
754 #ifndef PRODUCT
755 if (ArchiveHeapTestClass != nullptr) {
756 size_t len = strlen(ArchiveHeapTestClass) + 1;
757 Array<char>* array = ArchiveBuilder::new_ro_array<char>((int)len);
758 strncpy(array->adr_at(0), ArchiveHeapTestClass, len);
759 _archived_ArchiveHeapTestClass = array;
760 }
761 #endif
762 if (log_is_enabled(Info, cds, heap)) {
763 print_stats();
764 }
765 }
766
767 void HeapShared::init_roots(oop roots_oop) {
768 if (roots_oop != nullptr) {
769 assert(ArchiveHeapLoader::is_in_use(), "must be");
770 _roots = OopHandle(Universe::vm_global(), roots_oop);
771 }
772 }
773
774 void HeapShared::serialize_tables(SerializeClosure* soc) {
775
776 #ifndef PRODUCT
777 soc->do_ptr(&_archived_ArchiveHeapTestClass);
778 if (soc->reading() && _archived_ArchiveHeapTestClass != nullptr) {
779 _test_class_name = _archived_ArchiveHeapTestClass->adr_at(0);
780 setup_test_class(_test_class_name);
781 }
782 #endif
783
784 _run_time_subgraph_info_table.serialize_header(soc);
785 }
786
787 static void verify_the_heap(Klass* k, const char* which) {
788 if (VerifyArchivedFields > 0) {
789 ResourceMark rm;
790 log_info(cds, heap)("Verify heap %s initializing static field(s) in %s",
791 which, k->external_name());
792
793 VM_Verify verify_op;
794 VMThread::execute(&verify_op);
795
796 if (VerifyArchivedFields > 1 && is_init_completed()) {
797 // At this time, the oop->klass() of some archived objects in the heap may not
798 // have been loaded into the system dictionary yet. Nevertheless, oop->klass() should
799 // have enough information (object size, oop maps, etc) so that a GC can be safely
800 // performed.
801 //
802 // -XX:VerifyArchivedFields=2 force a GC to happen in such an early stage
803 // to check for GC safety.
804 log_info(cds, heap)("Trigger GC %s initializing static field(s) in %s",
805 which, k->external_name());
806 FlagSetting fs1(VerifyBeforeGC, true);
807 FlagSetting fs2(VerifyDuringGC, true);
808 FlagSetting fs3(VerifyAfterGC, true);
809 Universe::heap()->collect(GCCause::_java_lang_system_gc);
810 }
811 }
812 }
813
814 // Before GC can execute, we must ensure that all oops reachable from HeapShared::roots()
815 // have a valid klass. I.e., oopDesc::klass() must have already been resolved.
816 //
817 // Note: if a ArchivedKlassSubGraphInfoRecord contains non-early classes, and JVMTI
818 // ClassFileLoadHook is enabled, it's possible for this class to be dynamically replaced. In
819 // this case, we will not load the ArchivedKlassSubGraphInfoRecord and will clear its roots.
820 void HeapShared::resolve_classes(JavaThread* current) {
821 assert(CDSConfig::is_using_archive(), "runtime only!");
822 if (!ArchiveHeapLoader::is_in_use()) {
823 return; // nothing to do
824 }
825 resolve_classes_for_subgraphs(current, archive_subgraph_entry_fields);
826 resolve_classes_for_subgraphs(current, fmg_archive_subgraph_entry_fields);
827 }
828
829 void HeapShared::resolve_classes_for_subgraphs(JavaThread* current, ArchivableStaticFieldInfo fields[]) {
830 for (int i = 0; fields[i].valid(); i++) {
831 ArchivableStaticFieldInfo* info = &fields[i];
832 TempNewSymbol klass_name = SymbolTable::new_symbol(info->klass_name);
833 InstanceKlass* k = SystemDictionaryShared::find_builtin_class(klass_name);
834 assert(k != nullptr && k->is_shared_boot_class(), "sanity");
835 resolve_classes_for_subgraph_of(current, k);
836 }
837 }
838
839 void HeapShared::resolve_classes_for_subgraph_of(JavaThread* current, Klass* k) {
840 JavaThread* THREAD = current;
841 ExceptionMark em(THREAD);
842 const ArchivedKlassSubGraphInfoRecord* record =
843 resolve_or_init_classes_for_subgraph_of(k, /*do_init=*/false, THREAD);
844 if (HAS_PENDING_EXCEPTION) {
845 CLEAR_PENDING_EXCEPTION;
846 }
847 if (record == nullptr) {
848 clear_archived_roots_of(k);
849 }
850 }
851
852 void HeapShared::initialize_from_archived_subgraph(JavaThread* current, Klass* k) {
853 JavaThread* THREAD = current;
854 if (!ArchiveHeapLoader::is_in_use()) {
855 return; // nothing to do
856 }
857
858 ExceptionMark em(THREAD);
859 const ArchivedKlassSubGraphInfoRecord* record =
860 resolve_or_init_classes_for_subgraph_of(k, /*do_init=*/true, THREAD);
861
862 if (HAS_PENDING_EXCEPTION) {
863 CLEAR_PENDING_EXCEPTION;
864 // None of the field value will be set if there was an exception when initializing the classes.
865 // The java code will not see any of the archived objects in the
866 // subgraphs referenced from k in this case.
867 return;
868 }
869
870 if (record != nullptr) {
871 init_archived_fields_for(k, record);
872 }
873 }
874
875 const ArchivedKlassSubGraphInfoRecord*
876 HeapShared::resolve_or_init_classes_for_subgraph_of(Klass* k, bool do_init, TRAPS) {
877 assert(!CDSConfig::is_dumping_heap(), "Should not be called when dumping heap");
878
879 if (!k->is_shared()) {
880 return nullptr;
881 }
882 unsigned int hash = SystemDictionaryShared::hash_for_shared_dictionary_quick(k);
883 const ArchivedKlassSubGraphInfoRecord* record = _run_time_subgraph_info_table.lookup(k, hash, 0);
884
885 #ifndef PRODUCT
886 if (_test_class_name != nullptr && k->name()->equals(_test_class_name) && record != nullptr) {
887 _test_class = k;
888 _test_class_record = record;
889 }
890 #endif
891
892 // Initialize from archived data. Currently this is done only
893 // during VM initialization time. No lock is needed.
894 if (record == nullptr) {
895 if (log_is_enabled(Info, cds, heap)) {
896 ResourceMark rm(THREAD);
897 log_info(cds, heap)("subgraph %s is not recorded",
898 k->external_name());
899 }
900 return nullptr;
901 } else {
902 if (record->is_full_module_graph() && !CDSConfig::is_using_full_module_graph()) {
903 if (log_is_enabled(Info, cds, heap)) {
904 ResourceMark rm(THREAD);
905 log_info(cds, heap)("subgraph %s cannot be used because full module graph is disabled",
906 k->external_name());
907 }
908 return nullptr;
909 }
910
911 if (record->has_non_early_klasses() && JvmtiExport::should_post_class_file_load_hook()) {
912 if (log_is_enabled(Info, cds, heap)) {
913 ResourceMark rm(THREAD);
914 log_info(cds, heap)("subgraph %s cannot be used because JVMTI ClassFileLoadHook is enabled",
915 k->external_name());
916 }
917 return nullptr;
918 }
919
920 if (log_is_enabled(Info, cds, heap)) {
921 ResourceMark rm;
922 log_info(cds, heap)("%s subgraph %s ", do_init ? "init" : "resolve", k->external_name());
923 }
924
925 resolve_or_init(k, do_init, CHECK_NULL);
926
927 // Load/link/initialize the klasses of the objects in the subgraph.
928 // nullptr class loader is used.
929 Array<Klass*>* klasses = record->subgraph_object_klasses();
930 if (klasses != nullptr) {
931 for (int i = 0; i < klasses->length(); i++) {
932 Klass* klass = klasses->at(i);
933 if (!klass->is_shared()) {
934 return nullptr;
935 }
936 resolve_or_init(klass, do_init, CHECK_NULL);
937 }
938 }
939 }
940
941 return record;
942 }
943
944 void HeapShared::resolve_or_init(Klass* k, bool do_init, TRAPS) {
945 if (!do_init) {
946 if (k->class_loader_data() == nullptr) {
947 Klass* resolved_k = SystemDictionary::resolve_or_null(k->name(), CHECK);
948 assert(resolved_k == k, "classes used by archived heap must not be replaced by JVMTI ClassFileLoadHook");
949 }
950 } else {
951 assert(k->class_loader_data() != nullptr, "must have been resolved by HeapShared::resolve_classes");
952 if (k->is_instance_klass()) {
953 InstanceKlass* ik = InstanceKlass::cast(k);
954 ik->initialize(CHECK);
955 } else if (k->is_objArray_klass()) {
956 ObjArrayKlass* oak = ObjArrayKlass::cast(k);
957 oak->initialize(CHECK);
958 }
959 }
960 }
961
962 void HeapShared::init_archived_fields_for(Klass* k, const ArchivedKlassSubGraphInfoRecord* record) {
963 verify_the_heap(k, "before");
964
965 // Load the subgraph entry fields from the record and store them back to
966 // the corresponding fields within the mirror.
967 oop m = k->java_mirror();
968 Array<int>* entry_field_records = record->entry_field_records();
969 if (entry_field_records != nullptr) {
970 int efr_len = entry_field_records->length();
971 assert(efr_len % 2 == 0, "sanity");
972 for (int i = 0; i < efr_len; i += 2) {
973 int field_offset = entry_field_records->at(i);
974 int root_index = entry_field_records->at(i+1);
975 oop v = get_root(root_index, /*clear=*/true);
976 m->obj_field_put(field_offset, v);
977 log_debug(cds, heap)(" " PTR_FORMAT " init field @ %2d = " PTR_FORMAT, p2i(k), field_offset, p2i(v));
978 }
979
980 // Done. Java code can see the archived sub-graphs referenced from k's
981 // mirror after this point.
982 if (log_is_enabled(Info, cds, heap)) {
983 ResourceMark rm;
984 log_info(cds, heap)("initialize_from_archived_subgraph %s " PTR_FORMAT "%s",
985 k->external_name(), p2i(k), JvmtiExport::is_early_phase() ? " (early)" : "");
986 }
987 }
988
989 verify_the_heap(k, "after ");
990 }
991
992 void HeapShared::clear_archived_roots_of(Klass* k) {
993 unsigned int hash = SystemDictionaryShared::hash_for_shared_dictionary_quick(k);
994 const ArchivedKlassSubGraphInfoRecord* record = _run_time_subgraph_info_table.lookup(k, hash, 0);
995 if (record != nullptr) {
996 Array<int>* entry_field_records = record->entry_field_records();
997 if (entry_field_records != nullptr) {
998 int efr_len = entry_field_records->length();
999 assert(efr_len % 2 == 0, "sanity");
1000 for (int i = 0; i < efr_len; i += 2) {
1001 int root_index = entry_field_records->at(i+1);
1002 clear_root(root_index);
1003 }
1004 }
1005 }
1006 }
1007
1008 class WalkOopAndArchiveClosure: public BasicOopIterateClosure {
1009 int _level;
1010 bool _record_klasses_only;
1011 KlassSubGraphInfo* _subgraph_info;
1012 oop _referencing_obj;
1013
1014 // The following are for maintaining a stack for determining
1015 // CachedOopInfo::_referrer
1016 static WalkOopAndArchiveClosure* _current;
1017 WalkOopAndArchiveClosure* _last;
1018 public:
1019 WalkOopAndArchiveClosure(int level,
1020 bool record_klasses_only,
1021 KlassSubGraphInfo* subgraph_info,
1022 oop orig) :
1023 _level(level),
1024 _record_klasses_only(record_klasses_only),
1025 _subgraph_info(subgraph_info),
1026 _referencing_obj(orig) {
1027 _last = _current;
1028 _current = this;
1029 }
1030 ~WalkOopAndArchiveClosure() {
1031 _current = _last;
1032 }
1033 void do_oop(narrowOop *p) { WalkOopAndArchiveClosure::do_oop_work(p); }
1034 void do_oop( oop *p) { WalkOopAndArchiveClosure::do_oop_work(p); }
1035
1036 protected:
1037 template <class T> void do_oop_work(T *p) {
1038 oop obj = RawAccess<>::oop_load(p);
1039 if (!CompressedOops::is_null(obj)) {
1040 size_t field_delta = pointer_delta(p, _referencing_obj, sizeof(char));
1041
1042 if (!_record_klasses_only && log_is_enabled(Debug, cds, heap)) {
1043 ResourceMark rm;
1044 log_debug(cds, heap)("(%d) %s[" SIZE_FORMAT "] ==> " PTR_FORMAT " size " SIZE_FORMAT " %s", _level,
1045 _referencing_obj->klass()->external_name(), field_delta,
1046 p2i(obj), obj->size() * HeapWordSize, obj->klass()->external_name());
1047 if (log_is_enabled(Trace, cds, heap)) {
1048 LogTarget(Trace, cds, heap) log;
1049 LogStream out(log);
1050 obj->print_on(&out);
1051 }
1052 }
1053
1054 bool success = HeapShared::archive_reachable_objects_from(
1055 _level + 1, _subgraph_info, obj);
1056 assert(success, "VM should have exited with unarchivable objects for _level > 1");
1057 }
1058 }
1059
1060 public:
1061 static WalkOopAndArchiveClosure* current() { return _current; }
1062 oop referencing_obj() { return _referencing_obj; }
1063 KlassSubGraphInfo* subgraph_info() { return _subgraph_info; }
1064 };
1065
1066 WalkOopAndArchiveClosure* WalkOopAndArchiveClosure::_current = nullptr;
1067
1068 // Checks if an oop has any non-null oop fields
1069 class PointsToOopsChecker : public BasicOopIterateClosure {
1070 bool _result;
1071
1072 template <class T> void check(T *p) {
1073 _result |= (HeapAccess<>::oop_load(p) != nullptr);
1074 }
1075
1076 public:
1077 PointsToOopsChecker() : _result(false) {}
1078 void do_oop(narrowOop *p) { check(p); }
1079 void do_oop( oop *p) { check(p); }
1080 bool result() { return _result; }
1081 };
1082
1083 HeapShared::CachedOopInfo HeapShared::make_cached_oop_info(oop obj) {
1084 WalkOopAndArchiveClosure* walker = WalkOopAndArchiveClosure::current();
1085 oop referrer = (walker == nullptr) ? nullptr : walker->referencing_obj();
1086 PointsToOopsChecker points_to_oops_checker;
1087 obj->oop_iterate(&points_to_oops_checker);
1088 return CachedOopInfo(referrer, points_to_oops_checker.result());
1089 }
1090
1091 // (1) If orig_obj has not been archived yet, archive it.
1092 // (2) If orig_obj has not been seen yet (since start_recording_subgraph() was called),
1093 // trace all objects that are reachable from it, and make sure these objects are archived.
1094 // (3) Record the klasses of all orig_obj and all reachable objects.
1095 bool HeapShared::archive_reachable_objects_from(int level,
1096 KlassSubGraphInfo* subgraph_info,
1097 oop orig_obj) {
1098 assert(orig_obj != nullptr, "must be");
1099
1100 if (!JavaClasses::is_supported_for_archiving(orig_obj)) {
1101 // This object has injected fields that cannot be supported easily, so we disallow them for now.
1102 // If you get an error here, you probably made a change in the JDK library that has added
1103 // these objects that are referenced (directly or indirectly) by static fields.
1104 ResourceMark rm;
1105 log_error(cds, heap)("Cannot archive object of class %s", orig_obj->klass()->external_name());
1106 MetaspaceShared::unrecoverable_writing_error();
1107 }
1108
1109 // java.lang.Class instances cannot be included in an archived object sub-graph. We only support
1110 // them as Klass::_archived_mirror because they need to be specially restored at run time.
1111 //
1112 // If you get an error here, you probably made a change in the JDK library that has added a Class
1113 // object that is referenced (directly or indirectly) by static fields.
1114 if (java_lang_Class::is_instance(orig_obj) && subgraph_info != _default_subgraph_info) {
1115 log_error(cds, heap)("(%d) Unknown java.lang.Class object is in the archived sub-graph", level);
1116 MetaspaceShared::unrecoverable_writing_error();
1117 }
1118
1119 if (has_been_seen_during_subgraph_recording(orig_obj)) {
1120 // orig_obj has already been archived and traced. Nothing more to do.
1121 return true;
1122 } else {
1123 set_has_been_seen_during_subgraph_recording(orig_obj);
1124 }
1125
1126 bool already_archived = has_been_archived(orig_obj);
1127 bool record_klasses_only = already_archived;
1128 if (!already_archived) {
1129 ++_num_new_archived_objs;
1130 if (!archive_object(orig_obj)) {
1131 // Skip archiving the sub-graph referenced from the current entry field.
1132 ResourceMark rm;
1133 log_error(cds, heap)(
1134 "Cannot archive the sub-graph referenced from %s object ("
1135 PTR_FORMAT ") size " SIZE_FORMAT ", skipped.",
1136 orig_obj->klass()->external_name(), p2i(orig_obj), orig_obj->size() * HeapWordSize);
1137 if (level == 1) {
1138 // Don't archive a subgraph root that's too big. For archives static fields, that's OK
1139 // as the Java code will take care of initializing this field dynamically.
1140 return false;
1141 } else {
1142 // We don't know how to handle an object that has been archived, but some of its reachable
1143 // objects cannot be archived. Bail out for now. We might need to fix this in the future if
1144 // we have a real use case.
1145 MetaspaceShared::unrecoverable_writing_error();
1146 }
1147 }
1148 }
1149
1150 Klass *orig_k = orig_obj->klass();
1151 subgraph_info->add_subgraph_object_klass(orig_k);
1152
1153 WalkOopAndArchiveClosure walker(level, record_klasses_only, subgraph_info, orig_obj);
1154 orig_obj->oop_iterate(&walker);
1155
1156 if (CDSEnumKlass::is_enum_obj(orig_obj)) {
1157 CDSEnumKlass::handle_enum_obj(level + 1, subgraph_info, orig_obj);
1158 }
1159 return true;
1160 }
1161
1162 //
1163 // Start from the given static field in a java mirror and archive the
1164 // complete sub-graph of java heap objects that are reached directly
1165 // or indirectly from the starting object by following references.
1166 // Sub-graph archiving restrictions (current):
1167 //
1168 // - All classes of objects in the archived sub-graph (including the
1169 // entry class) must be boot class only.
1170 // - No java.lang.Class instance (java mirror) can be included inside
1171 // an archived sub-graph. Mirror can only be the sub-graph entry object.
1172 //
1173 // The Java heap object sub-graph archiving process (see
1174 // WalkOopAndArchiveClosure):
1175 //
1176 // 1) Java object sub-graph archiving starts from a given static field
1177 // within a Class instance (java mirror). If the static field is a
1178 // reference field and points to a non-null java object, proceed to
1179 // the next step.
1180 //
1181 // 2) Archives the referenced java object. If an archived copy of the
1182 // current object already exists, updates the pointer in the archived
1183 // copy of the referencing object to point to the current archived object.
1184 // Otherwise, proceed to the next step.
1185 //
1186 // 3) Follows all references within the current java object and recursively
1187 // archive the sub-graph of objects starting from each reference.
1188 //
1189 // 4) Updates the pointer in the archived copy of referencing object to
1190 // point to the current archived object.
1191 //
1192 // 5) The Klass of the current java object is added to the list of Klasses
1193 // for loading and initializing before any object in the archived graph can
1194 // be accessed at runtime.
1195 //
1196 void HeapShared::archive_reachable_objects_from_static_field(InstanceKlass *k,
1197 const char* klass_name,
1198 int field_offset,
1199 const char* field_name) {
1200 assert(CDSConfig::is_dumping_heap(), "dump time only");
1201 assert(k->is_shared_boot_class(), "must be boot class");
1202
1203 oop m = k->java_mirror();
1204
1205 KlassSubGraphInfo* subgraph_info = get_subgraph_info(k);
1206 oop f = m->obj_field(field_offset);
1207
1208 log_debug(cds, heap)("Start archiving from: %s::%s (" PTR_FORMAT ")", klass_name, field_name, p2i(f));
1209
1210 if (!CompressedOops::is_null(f)) {
1211 if (log_is_enabled(Trace, cds, heap)) {
1212 LogTarget(Trace, cds, heap) log;
1213 LogStream out(log);
1214 f->print_on(&out);
1215 }
1216
1217 bool success = archive_reachable_objects_from(1, subgraph_info, f);
1218 if (!success) {
1219 log_error(cds, heap)("Archiving failed %s::%s (some reachable objects cannot be archived)",
1220 klass_name, field_name);
1221 } else {
1222 // Note: the field value is not preserved in the archived mirror.
1223 // Record the field as a new subGraph entry point. The recorded
1224 // information is restored from the archive at runtime.
1225 subgraph_info->add_subgraph_entry_field(field_offset, f);
1226 log_info(cds, heap)("Archived field %s::%s => " PTR_FORMAT, klass_name, field_name, p2i(f));
1227 }
1228 } else {
1229 // The field contains null, we still need to record the entry point,
1230 // so it can be restored at runtime.
1231 subgraph_info->add_subgraph_entry_field(field_offset, nullptr);
1232 }
1233 }
1234
1235 #ifndef PRODUCT
1236 class VerifySharedOopClosure: public BasicOopIterateClosure {
1237 public:
1238 void do_oop(narrowOop *p) { VerifySharedOopClosure::do_oop_work(p); }
1239 void do_oop( oop *p) { VerifySharedOopClosure::do_oop_work(p); }
1240
1241 protected:
1242 template <class T> void do_oop_work(T *p) {
1243 oop obj = RawAccess<>::oop_load(p);
1244 if (!CompressedOops::is_null(obj)) {
1245 HeapShared::verify_reachable_objects_from(obj);
1246 }
1247 }
1248 };
1249
1250 void HeapShared::verify_subgraph_from_static_field(InstanceKlass* k, int field_offset) {
1251 assert(CDSConfig::is_dumping_heap(), "dump time only");
1252 assert(k->is_shared_boot_class(), "must be boot class");
1253
1254 oop m = k->java_mirror();
1255 oop f = m->obj_field(field_offset);
1256 if (!CompressedOops::is_null(f)) {
1257 verify_subgraph_from(f);
1258 }
1259 }
1260
1261 void HeapShared::verify_subgraph_from(oop orig_obj) {
1262 if (!has_been_archived(orig_obj)) {
1263 // It's OK for the root of a subgraph to be not archived. See comments in
1264 // archive_reachable_objects_from().
1265 return;
1266 }
1267
1268 // Verify that all objects reachable from orig_obj are archived.
1269 init_seen_objects_table();
1270 verify_reachable_objects_from(orig_obj);
1271 delete_seen_objects_table();
1272 }
1273
1274 void HeapShared::verify_reachable_objects_from(oop obj) {
1275 _num_total_verifications ++;
1276 if (!has_been_seen_during_subgraph_recording(obj)) {
1277 set_has_been_seen_during_subgraph_recording(obj);
1278 assert(has_been_archived(obj), "must be");
1279 VerifySharedOopClosure walker;
1280 obj->oop_iterate(&walker);
1281 }
1282 }
1283 #endif
1284
1285 // The "default subgraph" contains special objects (see heapShared.hpp) that
1286 // can be accessed before we load any Java classes (including java/lang/Class).
1287 // Make sure that these are only instances of the very few specific types
1288 // that we can handle.
1289 void HeapShared::check_default_subgraph_classes() {
1290 GrowableArray<Klass*>* klasses = _default_subgraph_info->subgraph_object_klasses();
1291 int num = klasses->length();
1292 for (int i = 0; i < num; i++) {
1293 Klass* subgraph_k = klasses->at(i);
1294 if (log_is_enabled(Info, cds, heap)) {
1295 ResourceMark rm;
1296 log_info(cds, heap)(
1297 "Archived object klass (default subgraph %d) => %s",
1298 i, subgraph_k->external_name());
1299 }
1300
1301 Symbol* name = ArchiveBuilder::current()->get_source_addr(subgraph_k->name());
1302 guarantee(name == vmSymbols::java_lang_Class() ||
1303 name == vmSymbols::java_lang_String() ||
1304 name == vmSymbols::java_lang_ArithmeticException() ||
1305 name == vmSymbols::java_lang_NullPointerException() ||
1306 name == vmSymbols::java_lang_InternalError() ||
1307 name == vmSymbols::object_array_signature() ||
1308 name == vmSymbols::byte_array_signature() ||
1309 name == vmSymbols::char_array_signature(),
1310 "default subgraph can have only these objects");
1311 }
1312 }
1313
1314 HeapShared::SeenObjectsTable* HeapShared::_seen_objects_table = nullptr;
1315 int HeapShared::_num_new_walked_objs;
1316 int HeapShared::_num_new_archived_objs;
1317 int HeapShared::_num_old_recorded_klasses;
1318
1319 int HeapShared::_num_total_subgraph_recordings = 0;
1320 int HeapShared::_num_total_walked_objs = 0;
1321 int HeapShared::_num_total_archived_objs = 0;
1322 int HeapShared::_num_total_recorded_klasses = 0;
1323 int HeapShared::_num_total_verifications = 0;
1324
1325 bool HeapShared::has_been_seen_during_subgraph_recording(oop obj) {
1326 return _seen_objects_table->get(obj) != nullptr;
1327 }
1328
1329 void HeapShared::set_has_been_seen_during_subgraph_recording(oop obj) {
1330 assert(!has_been_seen_during_subgraph_recording(obj), "sanity");
1331 _seen_objects_table->put_when_absent(obj, true);
1332 _seen_objects_table->maybe_grow();
1333 ++ _num_new_walked_objs;
1334 }
1335
1336 void HeapShared::start_recording_subgraph(InstanceKlass *k, const char* class_name, bool is_full_module_graph) {
1337 log_info(cds, heap)("Start recording subgraph(s) for archived fields in %s", class_name);
1338 init_subgraph_info(k, is_full_module_graph);
1339 init_seen_objects_table();
1340 _num_new_walked_objs = 0;
1341 _num_new_archived_objs = 0;
1342 _num_old_recorded_klasses = get_subgraph_info(k)->num_subgraph_object_klasses();
1343 }
1344
1345 void HeapShared::done_recording_subgraph(InstanceKlass *k, const char* class_name) {
1346 int num_new_recorded_klasses = get_subgraph_info(k)->num_subgraph_object_klasses() -
1347 _num_old_recorded_klasses;
1348 log_info(cds, heap)("Done recording subgraph(s) for archived fields in %s: "
1349 "walked %d objs, archived %d new objs, recorded %d classes",
1350 class_name, _num_new_walked_objs, _num_new_archived_objs,
1351 num_new_recorded_klasses);
1352
1353 delete_seen_objects_table();
1354
1355 _num_total_subgraph_recordings ++;
1356 _num_total_walked_objs += _num_new_walked_objs;
1357 _num_total_archived_objs += _num_new_archived_objs;
1358 _num_total_recorded_klasses += num_new_recorded_klasses;
1359 }
1360
1361 class ArchivableStaticFieldFinder: public FieldClosure {
1362 InstanceKlass* _ik;
1363 Symbol* _field_name;
1364 bool _found;
1365 int _offset;
1366 public:
1367 ArchivableStaticFieldFinder(InstanceKlass* ik, Symbol* field_name) :
1368 _ik(ik), _field_name(field_name), _found(false), _offset(-1) {}
1369
1370 virtual void do_field(fieldDescriptor* fd) {
1371 if (fd->name() == _field_name) {
1372 assert(!_found, "fields can never be overloaded");
1373 if (is_reference_type(fd->field_type())) {
1374 _found = true;
1375 _offset = fd->offset();
1376 }
1377 }
1378 }
1379 bool found() { return _found; }
1380 int offset() { return _offset; }
1381 };
1382
1383 void HeapShared::init_subgraph_entry_fields(ArchivableStaticFieldInfo fields[],
1384 TRAPS) {
1385 for (int i = 0; fields[i].valid(); i++) {
1386 ArchivableStaticFieldInfo* info = &fields[i];
1387 TempNewSymbol klass_name = SymbolTable::new_symbol(info->klass_name);
1388 TempNewSymbol field_name = SymbolTable::new_symbol(info->field_name);
1389 ResourceMark rm; // for stringStream::as_string() etc.
1390
1391 #ifndef PRODUCT
1392 bool is_test_class = (ArchiveHeapTestClass != nullptr) && (strcmp(info->klass_name, ArchiveHeapTestClass) == 0);
1393 const char* test_class_name = ArchiveHeapTestClass;
1394 #else
1395 bool is_test_class = false;
1396 const char* test_class_name = ""; // avoid C++ printf checks warnings.
1397 #endif
1398
1399 if (is_test_class) {
1400 log_warning(cds)("Loading ArchiveHeapTestClass %s ...", test_class_name);
1401 }
1402
1403 Klass* k = SystemDictionary::resolve_or_fail(klass_name, true, THREAD);
1404 if (HAS_PENDING_EXCEPTION) {
1405 CLEAR_PENDING_EXCEPTION;
1406 stringStream st;
1407 st.print("Fail to initialize archive heap: %s cannot be loaded by the boot loader", info->klass_name);
1408 THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(), st.as_string());
1409 }
1410
1411 if (!k->is_instance_klass()) {
1412 stringStream st;
1413 st.print("Fail to initialize archive heap: %s is not an instance class", info->klass_name);
1414 THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(), st.as_string());
1415 }
1416
1417 InstanceKlass* ik = InstanceKlass::cast(k);
1418 assert(InstanceKlass::cast(ik)->is_shared_boot_class(),
1419 "Only support boot classes");
1420
1421 if (is_test_class) {
1422 if (ik->module()->is_named()) {
1423 // We don't want ArchiveHeapTestClass to be abused to easily load/initialize arbitrary
1424 // core-lib classes. You need to at least append to the bootclasspath.
1425 stringStream st;
1426 st.print("ArchiveHeapTestClass %s is not in unnamed module", test_class_name);
1427 THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(), st.as_string());
1428 }
1429
1430 if (ik->package() != nullptr) {
1431 // This restriction makes HeapShared::is_a_test_class_in_unnamed_module() easy.
1432 stringStream st;
1433 st.print("ArchiveHeapTestClass %s is not in unnamed package", test_class_name);
1434 THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(), st.as_string());
1435 }
1436 } else {
1437 if (ik->module()->name() != vmSymbols::java_base()) {
1438 // We don't want to deal with cases when a module is unavailable at runtime.
1439 // FUTURE -- load from archived heap only when module graph has not changed
1440 // between dump and runtime.
1441 stringStream st;
1442 st.print("%s is not in java.base module", info->klass_name);
1443 THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(), st.as_string());
1444 }
1445 }
1446
1447 if (is_test_class) {
1448 log_warning(cds)("Initializing ArchiveHeapTestClass %s ...", test_class_name);
1449 }
1450 ik->initialize(CHECK);
1451
1452 ArchivableStaticFieldFinder finder(ik, field_name);
1453 ik->do_local_static_fields(&finder);
1454 if (!finder.found()) {
1455 stringStream st;
1456 st.print("Unable to find the static T_OBJECT field %s::%s", info->klass_name, info->field_name);
1457 THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(), st.as_string());
1458 }
1459
1460 info->klass = ik;
1461 info->offset = finder.offset();
1462 }
1463 }
1464
1465 void HeapShared::init_subgraph_entry_fields(TRAPS) {
1466 assert(HeapShared::can_write(), "must be");
1467 _dump_time_subgraph_info_table = new (mtClass)DumpTimeKlassSubGraphInfoTable();
1468 init_subgraph_entry_fields(archive_subgraph_entry_fields, CHECK);
1469 if (CDSConfig::is_dumping_full_module_graph()) {
1470 init_subgraph_entry_fields(fmg_archive_subgraph_entry_fields, CHECK);
1471 }
1472 }
1473
1474 #ifndef PRODUCT
1475 void HeapShared::setup_test_class(const char* test_class_name) {
1476 ArchivableStaticFieldInfo* p = archive_subgraph_entry_fields;
1477 int num_slots = sizeof(archive_subgraph_entry_fields) / sizeof(ArchivableStaticFieldInfo);
1478 assert(p[num_slots - 2].klass_name == nullptr, "must have empty slot that's patched below");
1479 assert(p[num_slots - 1].klass_name == nullptr, "must have empty slot that marks the end of the list");
1480
1481 if (test_class_name != nullptr) {
1482 p[num_slots - 2].klass_name = test_class_name;
1483 p[num_slots - 2].field_name = ARCHIVE_TEST_FIELD_NAME;
1484 }
1485 }
1486
1487 // See if ik is one of the test classes that are pulled in by -XX:ArchiveHeapTestClass
1488 // during runtime. This may be called before the module system is initialized so
1489 // we cannot rely on InstanceKlass::module(), etc.
1490 bool HeapShared::is_a_test_class_in_unnamed_module(Klass* ik) {
1491 if (_test_class != nullptr) {
1492 if (ik == _test_class) {
1493 return true;
1494 }
1495 Array<Klass*>* klasses = _test_class_record->subgraph_object_klasses();
1496 if (klasses == nullptr) {
1497 return false;
1498 }
1499
1500 for (int i = 0; i < klasses->length(); i++) {
1501 Klass* k = klasses->at(i);
1502 if (k == ik) {
1503 Symbol* name;
1504 if (k->is_instance_klass()) {
1505 name = InstanceKlass::cast(k)->name();
1506 } else if (k->is_objArray_klass()) {
1507 Klass* bk = ObjArrayKlass::cast(k)->bottom_klass();
1508 if (!bk->is_instance_klass()) {
1509 return false;
1510 }
1511 name = bk->name();
1512 } else {
1513 return false;
1514 }
1515
1516 // See KlassSubGraphInfo::check_allowed_klass() - only two types of
1517 // classes are allowed:
1518 // (A) java.base classes (which must not be in the unnamed module)
1519 // (B) test classes which must be in the unnamed package of the unnamed module.
1520 // So if we see a '/' character in the class name, it must be in (A);
1521 // otherwise it must be in (B).
1522 if (name->index_of_at(0, "/", 1) >= 0) {
1523 return false; // (A)
1524 }
1525
1526 return true; // (B)
1527 }
1528 }
1529 }
1530
1531 return false;
1532 }
1533 #endif
1534
1535 void HeapShared::init_for_dumping(TRAPS) {
1536 if (HeapShared::can_write()) {
1537 setup_test_class(ArchiveHeapTestClass);
1538 _dumped_interned_strings = new (mtClass)DumpedInternedStrings(INITIAL_TABLE_SIZE, MAX_TABLE_SIZE);
1539 init_subgraph_entry_fields(CHECK);
1540 }
1541 }
1542
1543 void HeapShared::archive_object_subgraphs(ArchivableStaticFieldInfo fields[],
1544 bool is_full_module_graph) {
1545 _num_total_subgraph_recordings = 0;
1546 _num_total_walked_objs = 0;
1547 _num_total_archived_objs = 0;
1548 _num_total_recorded_klasses = 0;
1549 _num_total_verifications = 0;
1550
1551 // For each class X that has one or more archived fields:
1552 // [1] Dump the subgraph of each archived field
1553 // [2] Create a list of all the class of the objects that can be reached
1554 // by any of these static fields.
1555 // At runtime, these classes are initialized before X's archived fields
1556 // are restored by HeapShared::initialize_from_archived_subgraph().
1557 for (int i = 0; fields[i].valid(); ) {
1558 ArchivableStaticFieldInfo* info = &fields[i];
1559 const char* klass_name = info->klass_name;
1560 start_recording_subgraph(info->klass, klass_name, is_full_module_graph);
1561
1562 // If you have specified consecutive fields of the same klass in
1563 // fields[], these will be archived in the same
1564 // {start_recording_subgraph ... done_recording_subgraph} pass to
1565 // save time.
1566 for (; fields[i].valid(); i++) {
1567 ArchivableStaticFieldInfo* f = &fields[i];
1568 if (f->klass_name != klass_name) {
1569 break;
1570 }
1571
1572 archive_reachable_objects_from_static_field(f->klass, f->klass_name,
1573 f->offset, f->field_name);
1574 }
1575 done_recording_subgraph(info->klass, klass_name);
1576 }
1577
1578 log_info(cds, heap)("Archived subgraph records = %d",
1579 _num_total_subgraph_recordings);
1580 log_info(cds, heap)(" Walked %d objects", _num_total_walked_objs);
1581 log_info(cds, heap)(" Archived %d objects", _num_total_archived_objs);
1582 log_info(cds, heap)(" Recorded %d klasses", _num_total_recorded_klasses);
1583
1584 #ifndef PRODUCT
1585 for (int i = 0; fields[i].valid(); i++) {
1586 ArchivableStaticFieldInfo* f = &fields[i];
1587 verify_subgraph_from_static_field(f->klass, f->offset);
1588 }
1589 log_info(cds, heap)(" Verified %d references", _num_total_verifications);
1590 #endif
1591 }
1592
1593 // Not all the strings in the global StringTable are dumped into the archive, because
1594 // some of those strings may be only referenced by classes that are excluded from
1595 // the archive. We need to explicitly mark the strings that are:
1596 // [1] used by classes that WILL be archived;
1597 // [2] included in the SharedArchiveConfigFile.
1598 void HeapShared::add_to_dumped_interned_strings(oop string) {
1599 assert_at_safepoint(); // DumpedInternedStrings uses raw oops
1600 assert(!ArchiveHeapWriter::is_string_too_large_to_archive(string), "must be");
1601 bool created;
1602 _dumped_interned_strings->put_if_absent(string, true, &created);
1603 if (created) {
1604 _dumped_interned_strings->maybe_grow();
1605 }
1606 }
1607
1608 #ifndef PRODUCT
1609 // At dump-time, find the location of all the non-null oop pointers in an archived heap
1610 // region. This way we can quickly relocate all the pointers without using
1611 // BasicOopIterateClosure at runtime.
1612 class FindEmbeddedNonNullPointers: public BasicOopIterateClosure {
1613 void* _start;
1614 BitMap *_oopmap;
1615 int _num_total_oops;
1616 int _num_null_oops;
1617 public:
1618 FindEmbeddedNonNullPointers(void* start, BitMap* oopmap)
1619 : _start(start), _oopmap(oopmap), _num_total_oops(0), _num_null_oops(0) {}
1620
1621 virtual void do_oop(narrowOop* p) {
1622 assert(UseCompressedOops, "sanity");
1623 _num_total_oops ++;
1624 narrowOop v = *p;
1625 if (!CompressedOops::is_null(v)) {
1626 size_t idx = p - (narrowOop*)_start;
1627 _oopmap->set_bit(idx);
1628 } else {
1629 _num_null_oops ++;
1630 }
1631 }
1632 virtual void do_oop(oop* p) {
1633 assert(!UseCompressedOops, "sanity");
1634 _num_total_oops ++;
1635 if ((*p) != nullptr) {
1636 size_t idx = p - (oop*)_start;
1637 _oopmap->set_bit(idx);
1638 } else {
1639 _num_null_oops ++;
1640 }
1641 }
1642 int num_total_oops() const { return _num_total_oops; }
1643 int num_null_oops() const { return _num_null_oops; }
1644 };
1645 #endif
1646
1647 #ifndef PRODUCT
1648 ResourceBitMap HeapShared::calculate_oopmap(MemRegion region) {
1649 size_t num_bits = region.byte_size() / (UseCompressedOops ? sizeof(narrowOop) : sizeof(oop));
1650 ResourceBitMap oopmap(num_bits);
1651
1652 HeapWord* p = region.start();
1653 HeapWord* end = region.end();
1654 FindEmbeddedNonNullPointers finder((void*)p, &oopmap);
1655
1656 int num_objs = 0;
1657 while (p < end) {
1658 oop o = cast_to_oop(p);
1659 o->oop_iterate(&finder);
1660 p += o->size();
1661 ++ num_objs;
1662 }
1663
1664 log_info(cds, heap)("calculate_oopmap: objects = %6d, oop fields = %7d (nulls = %7d)",
1665 num_objs, finder.num_total_oops(), finder.num_null_oops());
1666 return oopmap;
1667 }
1668
1669 #endif // !PRODUCT
1670
1671 void HeapShared::count_allocation(size_t size) {
1672 _total_obj_count ++;
1673 _total_obj_size += size;
1674 for (int i = 0; i < ALLOC_STAT_SLOTS; i++) {
1675 if (size <= (size_t(1) << i)) {
1676 _alloc_count[i] ++;
1677 _alloc_size[i] += size;
1678 return;
1679 }
1680 }
1681 }
1682
1683 static double avg_size(size_t size, size_t count) {
1684 double avg = 0;
1685 if (count > 0) {
1686 avg = double(size * HeapWordSize) / double(count);
1687 }
1688 return avg;
1689 }
1690
1691 void HeapShared::print_stats() {
1692 size_t huge_count = _total_obj_count;
1693 size_t huge_size = _total_obj_size;
1694
1695 for (int i = 0; i < ALLOC_STAT_SLOTS; i++) {
1696 size_t byte_size_limit = (size_t(1) << i) * HeapWordSize;
1697 size_t count = _alloc_count[i];
1698 size_t size = _alloc_size[i];
1699 log_info(cds, heap)(SIZE_FORMAT_W(8) " objects are <= " SIZE_FORMAT_W(-6)
1700 " bytes (total " SIZE_FORMAT_W(8) " bytes, avg %8.1f bytes)",
1701 count, byte_size_limit, size * HeapWordSize, avg_size(size, count));
1702 huge_count -= count;
1703 huge_size -= size;
1704 }
1705
1706 log_info(cds, heap)(SIZE_FORMAT_W(8) " huge objects (total " SIZE_FORMAT_W(8) " bytes"
1707 ", avg %8.1f bytes)",
1708 huge_count, huge_size * HeapWordSize,
1709 avg_size(huge_size, huge_count));
1710 log_info(cds, heap)(SIZE_FORMAT_W(8) " total objects (total " SIZE_FORMAT_W(8) " bytes"
1711 ", avg %8.1f bytes)",
1712 _total_obj_count, _total_obj_size * HeapWordSize,
1713 avg_size(_total_obj_size, _total_obj_count));
1714 }
1715
1716 bool HeapShared::is_archived_boot_layer_available(JavaThread* current) {
1717 TempNewSymbol klass_name = SymbolTable::new_symbol(ARCHIVED_BOOT_LAYER_CLASS);
1718 InstanceKlass* k = SystemDictionary::find_instance_klass(current, klass_name, Handle(), Handle());
1719 if (k == nullptr) {
1720 return false;
1721 } else {
1722 TempNewSymbol field_name = SymbolTable::new_symbol(ARCHIVED_BOOT_LAYER_FIELD);
1723 TempNewSymbol field_signature = SymbolTable::new_symbol("Ljdk/internal/module/ArchivedBootLayer;");
1724 fieldDescriptor fd;
1725 if (k->find_field(field_name, field_signature, true, &fd) != nullptr) {
1726 oop m = k->java_mirror();
1727 oop f = m->obj_field(fd.offset());
1728 if (CompressedOops::is_null(f)) {
1729 return false;
1730 }
1731 } else {
1732 return false;
1733 }
1734 }
1735 return true;
1736 }
1737
1738 #endif // INCLUDE_CDS_JAVA_HEAP
--- EOF ---