1 /*
2 * Copyright (c) 2018, 2021, 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/archiveUtils.hpp"
28 #include "cds/filemap.hpp"
29 #include "cds/heapShared.inline.hpp"
30 #include "cds/metaspaceShared.hpp"
31 #include "classfile/classLoaderData.hpp"
32 #include "classfile/classLoaderDataShared.hpp"
33 #include "classfile/javaClasses.inline.hpp"
34 #include "classfile/moduleEntry.hpp"
35 #include "classfile/stringTable.hpp"
36 #include "classfile/symbolTable.hpp"
37 #include "classfile/systemDictionary.hpp"
38 #include "classfile/systemDictionaryShared.hpp"
39 #include "classfile/vmClasses.hpp"
40 #include "classfile/vmSymbols.hpp"
41 #include "gc/shared/collectedHeap.hpp"
42 #include "gc/shared/gcLocker.hpp"
43 #include "gc/shared/gcVMOperations.hpp"
44 #include "logging/log.hpp"
45 #include "logging/logMessage.hpp"
46 #include "logging/logStream.hpp"
47 #include "memory/iterator.inline.hpp"
48 #include "memory/metadataFactory.hpp"
49 #include "memory/metaspaceClosure.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.hpp"
55 #include "oops/oop.inline.hpp"
56 #include "prims/jvmtiExport.hpp"
57 #include "runtime/fieldDescriptor.inline.hpp"
58 #include "runtime/globals_extension.hpp"
59 #include "runtime/init.hpp"
60 #include "runtime/java.hpp"
61 #include "runtime/javaCalls.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 bool HeapShared::_closed_regions_mapped = false;
72 bool HeapShared::_open_regions_mapped = false;
73 bool HeapShared::_is_loaded = false;
74 address HeapShared::_narrow_oop_base;
75 int HeapShared::_narrow_oop_shift;
76 DumpedInternedStrings *HeapShared::_dumped_interned_strings = NULL;
77
78 uintptr_t HeapShared::_loaded_heap_bottom = 0;
79 uintptr_t HeapShared::_loaded_heap_top = 0;
80 uintptr_t HeapShared::_dumptime_base_0 = UINTPTR_MAX;
81 uintptr_t HeapShared::_dumptime_base_1 = UINTPTR_MAX;
82 uintptr_t HeapShared::_dumptime_base_2 = UINTPTR_MAX;
83 uintptr_t HeapShared::_dumptime_base_3 = UINTPTR_MAX;
84 uintptr_t HeapShared::_dumptime_top = 0;
85 intx HeapShared::_runtime_offset_0 = 0;
86 intx HeapShared::_runtime_offset_1 = 0;
87 intx HeapShared::_runtime_offset_2 = 0;
88 intx HeapShared::_runtime_offset_3 = 0;
89 bool HeapShared::_loading_failed = false;
90 //
91 // If you add new entries to the following tables, you should know what you're doing!
92 //
93
94 // Entry fields for shareable subgraphs archived in the closed archive heap
95 // region. Warning: Objects in the subgraphs should not have reference fields
96 // assigned at runtime.
97 static ArchivableStaticFieldInfo closed_archive_subgraph_entry_fields[] = {
98 {"java/lang/Integer$IntegerCache", "archivedCache"},
99 {"java/lang/Long$LongCache", "archivedCache"},
100 {"java/lang/Byte$ByteCache", "archivedCache"},
101 {"java/lang/Short$ShortCache", "archivedCache"},
102 {"java/lang/Character$CharacterCache", "archivedCache"},
103 {"java/util/jar/Attributes$Name", "KNOWN_NAMES"},
104 {"sun/util/locale/BaseLocale", "constantBaseLocales"},
105 };
106 // Entry fields for subgraphs archived in the open archive heap region.
107 static ArchivableStaticFieldInfo open_archive_subgraph_entry_fields[] = {
108 {"jdk/internal/module/ArchivedModuleGraph", "archivedModuleGraph"},
109 {"java/util/ImmutableCollections", "archivedObjects"},
110 {"java/lang/ModuleLayer", "EMPTY_LAYER"},
111 {"java/lang/module/Configuration", "EMPTY_CONFIGURATION"},
112 {"jdk/internal/math/FDBigInteger", "archivedCaches"},
113 };
114
115 // Entry fields for subgraphs archived in the open archive heap region (full module graph).
116 static ArchivableStaticFieldInfo fmg_open_archive_subgraph_entry_fields[] = {
117 {"jdk/internal/loader/ArchivedClassLoaders", "archivedClassLoaders"},
118 {"jdk/internal/module/ArchivedBootLayer", "archivedBootLayer"},
119 {"java/lang/Module$ArchivedData", "archivedData"},
120 };
121
122 const static int num_closed_archive_subgraph_entry_fields =
123 sizeof(closed_archive_subgraph_entry_fields) / sizeof(ArchivableStaticFieldInfo);
124 const static int num_open_archive_subgraph_entry_fields =
125 sizeof(open_archive_subgraph_entry_fields) / sizeof(ArchivableStaticFieldInfo);
126 const static int num_fmg_open_archive_subgraph_entry_fields =
127 sizeof(fmg_open_archive_subgraph_entry_fields) / sizeof(ArchivableStaticFieldInfo);
128
129 GrowableArrayCHeap<oop, mtClassShared>* HeapShared::_pending_roots = NULL;
130 narrowOop HeapShared::_roots_narrow;
131 OopHandle HeapShared::_roots;
132
133 #ifdef ASSERT
134 bool HeapShared::is_archived_object_during_dumptime(oop p) {
135 assert(HeapShared::can_write(), "must be");
136 assert(DumpSharedSpaces, "this function is only used with -Xshare:dump");
137 return Universe::heap()->is_archived_object(p);
138 }
139 #endif
140
141 ////////////////////////////////////////////////////////////////
142 //
143 // Java heap object archiving support
144 //
145 ////////////////////////////////////////////////////////////////
146 void HeapShared::fixup_regions() {
147 FileMapInfo* mapinfo = FileMapInfo::current_info();
148 if (is_mapped()) {
149 mapinfo->fixup_mapped_heap_regions();
150 } else if (_loading_failed) {
151 fill_failed_loaded_region();
152 }
153 if (is_fully_available()) {
154 _roots = OopHandle(Universe::vm_global(), decode_from_archive(_roots_narrow));
155 if (!MetaspaceShared::use_full_module_graph()) {
156 // Need to remove all the archived java.lang.Module objects from HeapShared::roots().
157 ClassLoaderDataShared::clear_archived_oops();
158 }
159 }
160 SystemDictionaryShared::update_archived_mirror_native_pointers();
161 }
162
163 unsigned HeapShared::oop_hash(oop const& p) {
164 // We are at a safepoint, so the object won't move. It's OK to use its
165 // address as the hashcode.
166 // We can't use p->identity_hash() as it's not available for primitive oops.
167 assert_at_safepoint();
168 return (unsigned)(p2i(p) >> LogBytesPerWord);
169 }
170
171 static void reset_states(oop obj, TRAPS) {
172 Handle h_obj(THREAD, obj);
173 InstanceKlass* klass = InstanceKlass::cast(obj->klass());
174 TempNewSymbol method_name = SymbolTable::new_symbol("resetArchivedStates");
175 Symbol* method_sig = vmSymbols::void_method_signature();
176
177 while (klass != NULL) {
178 Method* method = klass->find_method(method_name, method_sig);
179 if (method != NULL) {
180 assert(method->is_private(), "must be");
181 if (log_is_enabled(Debug, cds)) {
182 ResourceMark rm(THREAD);
183 log_debug(cds)(" calling %s", method->name_and_sig_as_C_string());
184 }
185 JavaValue result(T_VOID);
186 JavaCalls::call_special(&result, h_obj, klass,
187 method_name, method_sig, CHECK);
188 }
189 klass = klass->java_super();
190 }
191 }
192
193 void HeapShared::reset_archived_object_states(TRAPS) {
194 assert(DumpSharedSpaces, "dump-time only");
195 log_debug(cds)("Resetting platform loader");
196 reset_states(SystemDictionary::java_platform_loader(), CHECK);
197 log_debug(cds)("Resetting system loader");
198 reset_states(SystemDictionary::java_system_loader(), CHECK);
199 }
200
201 HeapShared::ArchivedObjectCache* HeapShared::_archived_object_cache = NULL;
202 oop HeapShared::find_archived_heap_object(oop obj) {
203 assert(DumpSharedSpaces, "dump-time only");
204 ArchivedObjectCache* cache = archived_object_cache();
205 oop* p = cache->get(obj);
206 if (p != NULL) {
207 return *p;
208 } else {
209 return NULL;
210 }
211 }
212
213 int HeapShared::append_root(oop obj) {
214 assert(DumpSharedSpaces, "dump-time only");
215
216 // No GC should happen since we aren't scanning _pending_roots.
217 assert(Thread::current() == (Thread*)VMThread::vm_thread(), "should be in vm thread");
218
219 if (_pending_roots == NULL) {
220 _pending_roots = new GrowableArrayCHeap<oop, mtClassShared>(500);
221 }
222
223 return _pending_roots->append(obj);
224 }
225
226 objArrayOop HeapShared::roots() {
227 if (DumpSharedSpaces) {
228 assert(Thread::current() == (Thread*)VMThread::vm_thread(), "should be in vm thread");
229 if (!HeapShared::can_write()) {
230 return NULL;
231 }
232 } else {
233 assert(UseSharedSpaces, "must be");
234 }
235
236 objArrayOop roots = (objArrayOop)_roots.resolve();
237 assert(roots != NULL, "should have been initialized");
238 return roots;
239 }
240
241 void HeapShared::set_roots(narrowOop roots) {
242 assert(UseSharedSpaces, "runtime only");
243 assert(is_fully_available(), "must be");
244 _roots_narrow = roots;
245 }
246
247 // Returns an objArray that contains all the roots of the archived objects
248 oop HeapShared::get_root(int index, bool clear) {
249 assert(index >= 0, "sanity");
250 if (DumpSharedSpaces) {
251 assert(Thread::current() == (Thread*)VMThread::vm_thread(), "should be in vm thread");
252 assert(_pending_roots != NULL, "sanity");
253 return _pending_roots->at(index);
254 } else {
255 assert(UseSharedSpaces, "must be");
256 assert(!_roots.is_empty(), "must have loaded shared heap");
257 oop result = roots()->obj_at(index);
258 if (clear) {
259 clear_root(index);
260 }
261 return result;
262 }
263 }
264
265 void HeapShared::clear_root(int index) {
266 assert(index >= 0, "sanity");
267 assert(UseSharedSpaces, "must be");
268 if (is_fully_available()) {
269 if (log_is_enabled(Debug, cds, heap)) {
270 oop old = roots()->obj_at(index);
271 log_debug(cds, heap)("Clearing root %d: was " PTR_FORMAT, index, p2i(old));
272 }
273 roots()->obj_at_put(index, NULL);
274 }
275 }
276
277 oop HeapShared::archive_object(oop obj) {
278 assert(DumpSharedSpaces, "dump-time only");
279
280 oop ao = find_archived_heap_object(obj);
281 if (ao != NULL) {
282 // already archived
283 return ao;
284 }
285
286 int len = obj->size();
287 if (G1CollectedHeap::heap()->is_archive_alloc_too_large(len)) {
288 log_debug(cds, heap)("Cannot archive, object (" PTR_FORMAT ") is too large: " SIZE_FORMAT,
289 p2i(obj), (size_t)obj->size());
290 return NULL;
291 }
292
293 oop archived_oop = cast_to_oop(G1CollectedHeap::heap()->archive_mem_allocate(len));
294 if (archived_oop != NULL) {
295 Copy::aligned_disjoint_words(cast_from_oop<HeapWord*>(obj), cast_from_oop<HeapWord*>(archived_oop), len);
296 // Reinitialize markword to remove age/marking/locking/etc.
297 //
298 // We need to retain the identity_hash, because it may have been used by some hashtables
299 // in the shared heap. This also has the side effect of pre-initializing the
300 // identity_hash for all shared objects, so they are less likely to be written
301 // into during run time, increasing the potential of memory sharing.
302 if (!(EnableValhalla && obj->mark().is_inline_type())) {
303 int hash_original = obj->identity_hash();
304 archived_oop->set_mark(archived_oop->klass()->prototype_header().copy_set_hash(hash_original));
305 assert(archived_oop->mark().is_unlocked(), "sanity");
306
307 DEBUG_ONLY(int hash_archived = archived_oop->identity_hash());
308 assert(hash_original == hash_archived, "Different hash codes: original %x, archived %x", hash_original, hash_archived);
309 }
310
311 ArchivedObjectCache* cache = archived_object_cache();
312 cache->put(obj, archived_oop);
313 if (log_is_enabled(Debug, cds, heap)) {
314 ResourceMark rm;
315 log_debug(cds, heap)("Archived heap object " PTR_FORMAT " ==> " PTR_FORMAT " : %s",
316 p2i(obj), p2i(archived_oop), obj->klass()->external_name());
317 }
318 } else {
319 log_error(cds, heap)(
320 "Cannot allocate space for object " PTR_FORMAT " in archived heap region",
321 p2i(obj));
322 vm_direct_exit(-1,
323 err_msg("Out of memory. Please run with a larger Java heap, current MaxHeapSize = "
324 SIZE_FORMAT "M", MaxHeapSize/M));
325 }
326 return archived_oop;
327 }
328
329 void HeapShared::archive_klass_objects() {
330 GrowableArray<Klass*>* klasses = ArchiveBuilder::current()->klasses();
331 assert(klasses != NULL, "sanity");
332 for (int i = 0; i < klasses->length(); i++) {
333 Klass* k = ArchiveBuilder::get_relocated_klass(klasses->at(i));
334
335 // archive mirror object
336 java_lang_Class::archive_mirror(k);
337
338 // archive the resolved_referenes array
339 if (k->is_instance_klass()) {
340 InstanceKlass* ik = InstanceKlass::cast(k);
341 ik->constants()->archive_resolved_references();
342 }
343 }
344 }
345
346 void HeapShared::run_full_gc_in_vm_thread() {
347 if (HeapShared::can_write()) {
348 // Avoid fragmentation while archiving heap objects.
349 // We do this inside a safepoint, so that no further allocation can happen after GC
350 // has finished.
351 if (GCLocker::is_active()) {
352 // Just checking for safety ...
353 // This should not happen during -Xshare:dump. If you see this, probably the Java core lib
354 // has been modified such that JNI code is executed in some clean up threads after
355 // we have finished class loading.
356 log_warning(cds)("GC locker is held, unable to start extra compacting GC. This may produce suboptimal results.");
357 } else {
358 log_info(cds)("Run GC ...");
359 Universe::heap()->collect_as_vm_thread(GCCause::_archive_time_gc);
360 log_info(cds)("Run GC done");
361 }
362 }
363 }
364
365 void HeapShared::archive_objects(GrowableArray<MemRegion>* closed_regions,
366 GrowableArray<MemRegion>* open_regions) {
367
368 G1HeapVerifier::verify_ready_for_archiving();
369
370 {
371 NoSafepointVerifier nsv;
372
373 // Cache for recording where the archived objects are copied to
374 create_archived_object_cache();
375
376 log_info(cds)("Heap range = [" PTR_FORMAT " - " PTR_FORMAT "]",
377 p2i(CompressedOops::begin()), p2i(CompressedOops::end()));
378 log_info(cds)("Dumping objects to closed archive heap region ...");
379 copy_closed_objects(closed_regions);
380
381 log_info(cds)("Dumping objects to open archive heap region ...");
382 copy_open_objects(open_regions);
383
384 destroy_archived_object_cache();
385 }
386
387 G1HeapVerifier::verify_archive_regions();
388 }
389
390 void HeapShared::copy_closed_objects(GrowableArray<MemRegion>* closed_regions) {
391 assert(HeapShared::can_write(), "must be");
392
393 G1CollectedHeap::heap()->begin_archive_alloc_range();
394
395 // Archive interned string objects
396 StringTable::write_to_archive(_dumped_interned_strings);
397
398 archive_object_subgraphs(closed_archive_subgraph_entry_fields,
399 num_closed_archive_subgraph_entry_fields,
400 true /* is_closed_archive */,
401 false /* is_full_module_graph */);
402
403 G1CollectedHeap::heap()->end_archive_alloc_range(closed_regions,
404 os::vm_allocation_granularity());
405 }
406
407 void HeapShared::copy_open_objects(GrowableArray<MemRegion>* open_regions) {
408 assert(HeapShared::can_write(), "must be");
409
410 G1CollectedHeap::heap()->begin_archive_alloc_range(true /* open */);
411
412 java_lang_Class::archive_basic_type_mirrors();
413
414 archive_klass_objects();
415
416 archive_object_subgraphs(open_archive_subgraph_entry_fields,
417 num_open_archive_subgraph_entry_fields,
418 false /* is_closed_archive */,
419 false /* is_full_module_graph */);
420 if (MetaspaceShared::use_full_module_graph()) {
421 archive_object_subgraphs(fmg_open_archive_subgraph_entry_fields,
422 num_fmg_open_archive_subgraph_entry_fields,
423 false /* is_closed_archive */,
424 true /* is_full_module_graph */);
425 ClassLoaderDataShared::init_archived_oops();
426 }
427
428 copy_roots();
429
430 G1CollectedHeap::heap()->end_archive_alloc_range(open_regions,
431 os::vm_allocation_granularity());
432 }
433
434 // Copy _pending_archive_roots into an objArray
435 void HeapShared::copy_roots() {
436 int length = _pending_roots != NULL ? _pending_roots->length() : 0;
437 size_t size = objArrayOopDesc::object_size(length);
438 Klass* k = Universe::objectArrayKlassObj(); // already relocated to point to archived klass
439 HeapWord* mem = G1CollectedHeap::heap()->archive_mem_allocate(size);
440
441 memset(mem, 0, size * BytesPerWord);
442 {
443 // This is copied from MemAllocator::finish
444 oopDesc::set_mark(mem, k->prototype_header());
445 oopDesc::release_set_klass(mem, k);
446 }
447 {
448 // This is copied from ObjArrayAllocator::initialize
449 arrayOopDesc::set_length(mem, length);
450 }
451
452 _roots = OopHandle(Universe::vm_global(), cast_to_oop(mem));
453 for (int i = 0; i < length; i++) {
454 roots()->obj_at_put(i, _pending_roots->at(i));
455 }
456 log_info(cds)("archived obj roots[%d] = " SIZE_FORMAT " words, klass = %p, obj = %p", length, size, k, mem);
457 }
458
459 void HeapShared::init_narrow_oop_decoding(address base, int shift) {
460 _narrow_oop_base = base;
461 _narrow_oop_shift = shift;
462 }
463
464 //
465 // Subgraph archiving support
466 //
467 HeapShared::DumpTimeKlassSubGraphInfoTable* HeapShared::_dump_time_subgraph_info_table = NULL;
468 HeapShared::RunTimeKlassSubGraphInfoTable HeapShared::_run_time_subgraph_info_table;
469
470 // Get the subgraph_info for Klass k. A new subgraph_info is created if
471 // there is no existing one for k. The subgraph_info records the relocated
472 // Klass* of the original k.
473 KlassSubGraphInfo* HeapShared::init_subgraph_info(Klass* k, bool is_full_module_graph) {
474 assert(DumpSharedSpaces, "dump time only");
475 bool created;
476 Klass* relocated_k = ArchiveBuilder::get_relocated_klass(k);
477 KlassSubGraphInfo* info =
478 _dump_time_subgraph_info_table->put_if_absent(relocated_k, KlassSubGraphInfo(relocated_k, is_full_module_graph),
479 &created);
480 assert(created, "must not initialize twice");
481 return info;
482 }
483
484 KlassSubGraphInfo* HeapShared::get_subgraph_info(Klass* k) {
485 assert(DumpSharedSpaces, "dump time only");
486 Klass* relocated_k = ArchiveBuilder::get_relocated_klass(k);
487 KlassSubGraphInfo* info = _dump_time_subgraph_info_table->get(relocated_k);
488 assert(info != NULL, "must have been initialized");
489 return info;
490 }
491
492 // Add an entry field to the current KlassSubGraphInfo.
493 void KlassSubGraphInfo::add_subgraph_entry_field(
494 int static_field_offset, oop v, bool is_closed_archive) {
495 assert(DumpSharedSpaces, "dump time only");
496 if (_subgraph_entry_fields == NULL) {
497 _subgraph_entry_fields =
498 new(ResourceObj::C_HEAP, mtClass) GrowableArray<int>(10, mtClass);
499 }
500 _subgraph_entry_fields->append(static_field_offset);
501 _subgraph_entry_fields->append(HeapShared::append_root(v));
502 }
503
504 // Add the Klass* for an object in the current KlassSubGraphInfo's subgraphs.
505 // Only objects of boot classes can be included in sub-graph.
506 void KlassSubGraphInfo::add_subgraph_object_klass(Klass* orig_k) {
507 assert(DumpSharedSpaces, "dump time only");
508 Klass* relocated_k = ArchiveBuilder::get_relocated_klass(orig_k);
509
510 if (_subgraph_object_klasses == NULL) {
511 _subgraph_object_klasses =
512 new(ResourceObj::C_HEAP, mtClass) GrowableArray<Klass*>(50, mtClass);
513 }
514
515 assert(ArchiveBuilder::current()->is_in_buffer_space(relocated_k), "must be a shared class");
516
517 if (_k == relocated_k) {
518 // Don't add the Klass containing the sub-graph to it's own klass
519 // initialization list.
520 return;
521 }
522
523 if (relocated_k->is_instance_klass()) {
524 assert(InstanceKlass::cast(relocated_k)->is_shared_boot_class(),
525 "must be boot class");
526 // vmClasses::xxx_klass() are not updated, need to check
527 // the original Klass*
528 if (orig_k == vmClasses::String_klass() ||
529 orig_k == vmClasses::Object_klass()) {
530 // Initialized early during VM initialization. No need to be added
531 // to the sub-graph object class list.
532 return;
533 }
534 } else if (relocated_k->is_objArray_klass()) {
535 Klass* abk = ObjArrayKlass::cast(relocated_k)->bottom_klass();
536 if (abk->is_instance_klass()) {
537 assert(InstanceKlass::cast(abk)->is_shared_boot_class(),
538 "must be boot class");
539 }
540 if (relocated_k == Universe::objectArrayKlassObj()) {
541 // Initialized early during Universe::genesis. No need to be added
542 // to the list.
543 return;
544 }
545 } else {
546 assert(relocated_k->is_typeArray_klass(), "must be");
547 // Primitive type arrays are created early during Universe::genesis.
548 return;
549 }
550
551 if (log_is_enabled(Debug, cds, heap)) {
552 if (!_subgraph_object_klasses->contains(relocated_k)) {
553 ResourceMark rm;
554 log_debug(cds, heap)("Adding klass %s", orig_k->external_name());
555 }
556 }
557
558 _subgraph_object_klasses->append_if_missing(relocated_k);
559 _has_non_early_klasses |= is_non_early_klass(orig_k);
560 }
561
562 bool KlassSubGraphInfo::is_non_early_klass(Klass* k) {
563 if (k->is_objArray_klass()) {
564 k = ObjArrayKlass::cast(k)->bottom_klass();
565 }
566 if (k->is_instance_klass()) {
567 if (!SystemDictionaryShared::is_early_klass(InstanceKlass::cast(k))) {
568 ResourceMark rm;
569 log_info(cds, heap)("non-early: %s", k->external_name());
570 return true;
571 } else {
572 return false;
573 }
574 } else {
575 return false;
576 }
577 }
578
579 // Initialize an archived subgraph_info_record from the given KlassSubGraphInfo.
580 void ArchivedKlassSubGraphInfoRecord::init(KlassSubGraphInfo* info) {
581 _k = info->klass();
582 _entry_field_records = NULL;
583 _subgraph_object_klasses = NULL;
584 _is_full_module_graph = info->is_full_module_graph();
585
586 if (_is_full_module_graph) {
587 // Consider all classes referenced by the full module graph as early -- we will be
588 // allocating objects of these classes during JVMTI early phase, so they cannot
589 // be processed by (non-early) JVMTI ClassFileLoadHook
590 _has_non_early_klasses = false;
591 } else {
592 _has_non_early_klasses = info->has_non_early_klasses();
593 }
594
595 if (_has_non_early_klasses) {
596 ResourceMark rm;
597 log_info(cds, heap)(
598 "Subgraph of klass %s has non-early klasses and cannot be used when JVMTI ClassFileLoadHook is enabled",
599 _k->external_name());
600 }
601
602 // populate the entry fields
603 GrowableArray<int>* entry_fields = info->subgraph_entry_fields();
604 if (entry_fields != NULL) {
605 int num_entry_fields = entry_fields->length();
606 assert(num_entry_fields % 2 == 0, "sanity");
607 _entry_field_records =
608 ArchiveBuilder::new_ro_array<int>(num_entry_fields);
609 for (int i = 0 ; i < num_entry_fields; i++) {
610 _entry_field_records->at_put(i, entry_fields->at(i));
611 }
612 }
613
614 // the Klasses of the objects in the sub-graphs
615 GrowableArray<Klass*>* subgraph_object_klasses = info->subgraph_object_klasses();
616 if (subgraph_object_klasses != NULL) {
617 int num_subgraphs_klasses = subgraph_object_klasses->length();
618 _subgraph_object_klasses =
619 ArchiveBuilder::new_ro_array<Klass*>(num_subgraphs_klasses);
620 for (int i = 0; i < num_subgraphs_klasses; i++) {
621 Klass* subgraph_k = subgraph_object_klasses->at(i);
622 if (log_is_enabled(Info, cds, heap)) {
623 ResourceMark rm;
624 log_info(cds, heap)(
625 "Archived object klass %s (%2d) => %s",
626 _k->external_name(), i, subgraph_k->external_name());
627 }
628 _subgraph_object_klasses->at_put(i, subgraph_k);
629 ArchivePtrMarker::mark_pointer(_subgraph_object_klasses->adr_at(i));
630 }
631 }
632
633 ArchivePtrMarker::mark_pointer(&_k);
634 ArchivePtrMarker::mark_pointer(&_entry_field_records);
635 ArchivePtrMarker::mark_pointer(&_subgraph_object_klasses);
636 }
637
638 struct CopyKlassSubGraphInfoToArchive : StackObj {
639 CompactHashtableWriter* _writer;
640 CopyKlassSubGraphInfoToArchive(CompactHashtableWriter* writer) : _writer(writer) {}
641
642 bool do_entry(Klass* klass, KlassSubGraphInfo& info) {
643 if (info.subgraph_object_klasses() != NULL || info.subgraph_entry_fields() != NULL) {
644 ArchivedKlassSubGraphInfoRecord* record =
645 (ArchivedKlassSubGraphInfoRecord*)ArchiveBuilder::ro_region_alloc(sizeof(ArchivedKlassSubGraphInfoRecord));
646 record->init(&info);
647
648 unsigned int hash = SystemDictionaryShared::hash_for_shared_dictionary((address)klass);
649 u4 delta = ArchiveBuilder::current()->any_to_offset_u4(record);
650 _writer->add(hash, delta);
651 }
652 return true; // keep on iterating
653 }
654 };
655
656 // Build the records of archived subgraph infos, which include:
657 // - Entry points to all subgraphs from the containing class mirror. The entry
658 // points are static fields in the mirror. For each entry point, the field
659 // offset, value and is_closed_archive flag are recorded in the sub-graph
660 // info. The value is stored back to the corresponding field at runtime.
661 // - A list of klasses that need to be loaded/initialized before archived
662 // java object sub-graph can be accessed at runtime.
663 void HeapShared::write_subgraph_info_table() {
664 // Allocate the contents of the hashtable(s) inside the RO region of the CDS archive.
665 DumpTimeKlassSubGraphInfoTable* d_table = _dump_time_subgraph_info_table;
666 CompactHashtableStats stats;
667
668 _run_time_subgraph_info_table.reset();
669
670 CompactHashtableWriter writer(d_table->_count, &stats);
671 CopyKlassSubGraphInfoToArchive copy(&writer);
672 d_table->iterate(©);
673
674 writer.dump(&_run_time_subgraph_info_table, "subgraphs");
675 }
676
677 void HeapShared::serialize_subgraph_info_table_header(SerializeClosure* soc) {
678 _run_time_subgraph_info_table.serialize_header(soc);
679 }
680
681 static void verify_the_heap(Klass* k, const char* which) {
682 if (VerifyArchivedFields > 0) {
683 ResourceMark rm;
684 log_info(cds, heap)("Verify heap %s initializing static field(s) in %s",
685 which, k->external_name());
686
687 VM_Verify verify_op;
688 VMThread::execute(&verify_op);
689
690 if (VerifyArchivedFields > 1 && is_init_completed()) {
691 // At this time, the oop->klass() of some archived objects in the heap may not
692 // have been loaded into the system dictionary yet. Nevertheless, oop->klass() should
693 // have enough information (object size, oop maps, etc) so that a GC can be safely
694 // performed.
695 //
696 // -XX:VerifyArchivedFields=2 force a GC to happen in such an early stage
697 // to check for GC safety.
698 log_info(cds, heap)("Trigger GC %s initializing static field(s) in %s",
699 which, k->external_name());
700 FlagSetting fs1(VerifyBeforeGC, true);
701 FlagSetting fs2(VerifyDuringGC, true);
702 FlagSetting fs3(VerifyAfterGC, true);
703 Universe::heap()->collect(GCCause::_java_lang_system_gc);
704 }
705 }
706 }
707
708 // Before GC can execute, we must ensure that all oops reachable from HeapShared::roots()
709 // have a valid klass. I.e., oopDesc::klass() must have already been resolved.
710 //
711 // Note: if a ArchivedKlassSubGraphInfoRecord contains non-early classes, and JVMTI
712 // ClassFileLoadHook is enabled, it's possible for this class to be dynamically replaced. In
713 // this case, we will not load the ArchivedKlassSubGraphInfoRecord and will clear its roots.
714 void HeapShared::resolve_classes(JavaThread* THREAD) {
715 if (!is_fully_available()) {
716 return; // nothing to do
717 }
718 resolve_classes_for_subgraphs(closed_archive_subgraph_entry_fields,
719 num_closed_archive_subgraph_entry_fields,
720 THREAD);
721 resolve_classes_for_subgraphs(open_archive_subgraph_entry_fields,
722 num_open_archive_subgraph_entry_fields,
723 THREAD);
724 resolve_classes_for_subgraphs(fmg_open_archive_subgraph_entry_fields,
725 num_fmg_open_archive_subgraph_entry_fields,
726 THREAD);
727 }
728
729 void HeapShared::resolve_classes_for_subgraphs(ArchivableStaticFieldInfo fields[],
730 int num, JavaThread* THREAD) {
731 for (int i = 0; i < num; i++) {
732 ArchivableStaticFieldInfo* info = &fields[i];
733 TempNewSymbol klass_name = SymbolTable::new_symbol(info->klass_name);
734 InstanceKlass* k = SystemDictionaryShared::find_builtin_class(klass_name);
735 assert(k != NULL && k->is_shared_boot_class(), "sanity");
736 resolve_classes_for_subgraph_of(k, THREAD);
737 }
738 }
739
740 void HeapShared::resolve_classes_for_subgraph_of(Klass* k, JavaThread* THREAD) {
741 ExceptionMark em(THREAD);
742 const ArchivedKlassSubGraphInfoRecord* record =
743 resolve_or_init_classes_for_subgraph_of(k, /*do_init=*/false, THREAD);
744 if (HAS_PENDING_EXCEPTION) {
745 CLEAR_PENDING_EXCEPTION;
746 }
747 if (record == NULL) {
748 clear_archived_roots_of(k);
749 }
750 }
751
752 void HeapShared::initialize_from_archived_subgraph(Klass* k, JavaThread* THREAD) {
753 if (!is_fully_available()) {
754 return; // nothing to do
755 }
756
757 ExceptionMark em(THREAD);
758 const ArchivedKlassSubGraphInfoRecord* record =
759 resolve_or_init_classes_for_subgraph_of(k, /*do_init=*/true, THREAD);
760
761 if (HAS_PENDING_EXCEPTION) {
762 CLEAR_PENDING_EXCEPTION;
763 // None of the field value will be set if there was an exception when initializing the classes.
764 // The java code will not see any of the archived objects in the
765 // subgraphs referenced from k in this case.
766 return;
767 }
768
769 if (record != NULL) {
770 init_archived_fields_for(k, record);
771 }
772 }
773
774 const ArchivedKlassSubGraphInfoRecord*
775 HeapShared::resolve_or_init_classes_for_subgraph_of(Klass* k, bool do_init, TRAPS) {
776 assert(!DumpSharedSpaces, "Should not be called with DumpSharedSpaces");
777
778 if (!k->is_shared()) {
779 return NULL;
780 }
781 unsigned int hash = SystemDictionaryShared::hash_for_shared_dictionary_quick(k);
782 const ArchivedKlassSubGraphInfoRecord* record = _run_time_subgraph_info_table.lookup(k, hash, 0);
783
784 // Initialize from archived data. Currently this is done only
785 // during VM initialization time. No lock is needed.
786 if (record != NULL) {
787 if (record->is_full_module_graph() && !MetaspaceShared::use_full_module_graph()) {
788 if (log_is_enabled(Info, cds, heap)) {
789 ResourceMark rm(THREAD);
790 log_info(cds, heap)("subgraph %s cannot be used because full module graph is disabled",
791 k->external_name());
792 }
793 return NULL;
794 }
795
796 if (record->has_non_early_klasses() && JvmtiExport::should_post_class_file_load_hook()) {
797 if (log_is_enabled(Info, cds, heap)) {
798 ResourceMark rm(THREAD);
799 log_info(cds, heap)("subgraph %s cannot be used because JVMTI ClassFileLoadHook is enabled",
800 k->external_name());
801 }
802 return NULL;
803 }
804
805 resolve_or_init(k, do_init, CHECK_NULL);
806
807 // Load/link/initialize the klasses of the objects in the subgraph.
808 // NULL class loader is used.
809 Array<Klass*>* klasses = record->subgraph_object_klasses();
810 if (klasses != NULL) {
811 for (int i = 0; i < klasses->length(); i++) {
812 Klass* klass = klasses->at(i);
813 if (!klass->is_shared()) {
814 return NULL;
815 }
816 resolve_or_init(klass, do_init, CHECK_NULL);
817 }
818 }
819 }
820
821 return record;
822 }
823
824 void HeapShared::resolve_or_init(Klass* k, bool do_init, TRAPS) {
825 if (!do_init) {
826 if (k->class_loader_data() == NULL) {
827 Klass* resolved_k = SystemDictionary::resolve_or_null(k->name(), CHECK);
828 assert(resolved_k == k, "classes used by archived heap must not be replaced by JVMTI ClassFileLoadHook");
829 }
830 } else {
831 assert(k->class_loader_data() != NULL, "must have been resolved by HeapShared::resolve_classes");
832 if (k->is_instance_klass()) {
833 InstanceKlass* ik = InstanceKlass::cast(k);
834 ik->initialize(CHECK);
835 } else if (k->is_objArray_klass()) {
836 ObjArrayKlass* oak = ObjArrayKlass::cast(k);
837 oak->initialize(CHECK);
838 }
839 }
840 }
841
842 void HeapShared::init_archived_fields_for(Klass* k, const ArchivedKlassSubGraphInfoRecord* record) {
843 verify_the_heap(k, "before");
844
845 // Load the subgraph entry fields from the record and store them back to
846 // the corresponding fields within the mirror.
847 oop m = k->java_mirror();
848 Array<int>* entry_field_records = record->entry_field_records();
849 if (entry_field_records != NULL) {
850 int efr_len = entry_field_records->length();
851 assert(efr_len % 2 == 0, "sanity");
852 for (int i = 0; i < efr_len; i += 2) {
853 int field_offset = entry_field_records->at(i);
854 int root_index = entry_field_records->at(i+1);
855 oop v = get_root(root_index, /*clear=*/true);
856 m->obj_field_put(field_offset, v);
857 log_debug(cds, heap)(" " PTR_FORMAT " init field @ %2d = " PTR_FORMAT, p2i(k), field_offset, p2i(v));
858 }
859
860 // Done. Java code can see the archived sub-graphs referenced from k's
861 // mirror after this point.
862 if (log_is_enabled(Info, cds, heap)) {
863 ResourceMark rm;
864 log_info(cds, heap)("initialize_from_archived_subgraph %s " PTR_FORMAT "%s",
865 k->external_name(), p2i(k), JvmtiExport::is_early_phase() ? " (early)" : "");
866 }
867 }
868
869 verify_the_heap(k, "after ");
870 }
871
872 void HeapShared::clear_archived_roots_of(Klass* k) {
873 unsigned int hash = SystemDictionaryShared::hash_for_shared_dictionary_quick(k);
874 const ArchivedKlassSubGraphInfoRecord* record = _run_time_subgraph_info_table.lookup(k, hash, 0);
875 if (record != NULL) {
876 Array<int>* entry_field_records = record->entry_field_records();
877 if (entry_field_records != NULL) {
878 int efr_len = entry_field_records->length();
879 assert(efr_len % 2 == 0, "sanity");
880 for (int i = 0; i < efr_len; i += 2) {
881 int root_index = entry_field_records->at(i+1);
882 clear_root(root_index);
883 }
884 }
885 }
886 }
887
888 class WalkOopAndArchiveClosure: public BasicOopIterateClosure {
889 int _level;
890 bool _is_closed_archive;
891 bool _record_klasses_only;
892 KlassSubGraphInfo* _subgraph_info;
893 oop _orig_referencing_obj;
894 oop _archived_referencing_obj;
895 public:
896 WalkOopAndArchiveClosure(int level,
897 bool is_closed_archive,
898 bool record_klasses_only,
899 KlassSubGraphInfo* subgraph_info,
900 oop orig, oop archived) :
901 _level(level), _is_closed_archive(is_closed_archive),
902 _record_klasses_only(record_klasses_only),
903 _subgraph_info(subgraph_info),
904 _orig_referencing_obj(orig), _archived_referencing_obj(archived) {}
905 void do_oop(narrowOop *p) { WalkOopAndArchiveClosure::do_oop_work(p); }
906 void do_oop( oop *p) { WalkOopAndArchiveClosure::do_oop_work(p); }
907
908 protected:
909 template <class T> void do_oop_work(T *p) {
910 oop obj = RawAccess<>::oop_load(p);
911 if (!CompressedOops::is_null(obj)) {
912 assert(!HeapShared::is_archived_object_during_dumptime(obj),
913 "original objects must not point to archived objects");
914
915 size_t field_delta = pointer_delta(p, _orig_referencing_obj, sizeof(char));
916 T* new_p = (T*)(cast_from_oop<address>(_archived_referencing_obj) + field_delta);
917
918 if (!_record_klasses_only && log_is_enabled(Debug, cds, heap)) {
919 ResourceMark rm;
920 log_debug(cds, heap)("(%d) %s[" SIZE_FORMAT "] ==> " PTR_FORMAT " size " SIZE_FORMAT " %s", _level,
921 _orig_referencing_obj->klass()->external_name(), field_delta,
922 p2i(obj), obj->size() * HeapWordSize, obj->klass()->external_name());
923 LogTarget(Trace, cds, heap) log;
924 LogStream out(log);
925 obj->print_on(&out);
926 }
927
928 oop archived = HeapShared::archive_reachable_objects_from(
929 _level + 1, _subgraph_info, obj, _is_closed_archive);
930 assert(archived != NULL, "VM should have exited with unarchivable objects for _level > 1");
931 assert(HeapShared::is_archived_object_during_dumptime(archived), "must be");
932
933 if (!_record_klasses_only) {
934 // Update the reference in the archived copy of the referencing object.
935 log_debug(cds, heap)("(%d) updating oop @[" PTR_FORMAT "] " PTR_FORMAT " ==> " PTR_FORMAT,
936 _level, p2i(new_p), p2i(obj), p2i(archived));
937 RawAccess<IS_NOT_NULL>::oop_store(new_p, archived);
938 }
939 }
940 }
941 };
942
943 void HeapShared::check_closed_region_object(InstanceKlass* k) {
944 // Check fields in the object
945 for (JavaFieldStream fs(k); !fs.done(); fs.next()) {
946 if (!fs.access_flags().is_static()) {
947 BasicType ft = fs.field_descriptor().field_type();
948 if (!fs.access_flags().is_final() && is_reference_type(ft)) {
949 ResourceMark rm;
950 log_warning(cds, heap)(
951 "Please check reference field in %s instance in closed archive heap region: %s %s",
952 k->external_name(), (fs.name())->as_C_string(),
953 (fs.signature())->as_C_string());
954 }
955 }
956 }
957 }
958
959 void HeapShared::check_module_oop(oop orig_module_obj) {
960 assert(DumpSharedSpaces, "must be");
961 assert(java_lang_Module::is_instance(orig_module_obj), "must be");
962 ModuleEntry* orig_module_ent = java_lang_Module::module_entry_raw(orig_module_obj);
963 if (orig_module_ent == NULL) {
964 // These special Module objects are created in Java code. They are not
965 // defined via Modules::define_module(), so they don't have a ModuleEntry:
966 // java.lang.Module::ALL_UNNAMED_MODULE
967 // java.lang.Module::EVERYONE_MODULE
968 // jdk.internal.loader.ClassLoaders$BootClassLoader::unnamedModule
969 assert(java_lang_Module::name(orig_module_obj) == NULL, "must be unnamed");
970 log_info(cds, heap)("Module oop with No ModuleEntry* @[" PTR_FORMAT "]", p2i(orig_module_obj));
971 } else {
972 ClassLoaderData* loader_data = orig_module_ent->loader_data();
973 assert(loader_data->is_builtin_class_loader_data(), "must be");
974 }
975 }
976
977
978 // (1) If orig_obj has not been archived yet, archive it.
979 // (2) If orig_obj has not been seen yet (since start_recording_subgraph() was called),
980 // trace all objects that are reachable from it, and make sure these objects are archived.
981 // (3) Record the klasses of all orig_obj and all reachable objects.
982 oop HeapShared::archive_reachable_objects_from(int level,
983 KlassSubGraphInfo* subgraph_info,
984 oop orig_obj,
985 bool is_closed_archive) {
986 assert(orig_obj != NULL, "must be");
987 assert(!is_archived_object_during_dumptime(orig_obj), "sanity");
988
989 if (!JavaClasses::is_supported_for_archiving(orig_obj)) {
990 // This object has injected fields that cannot be supported easily, so we disallow them for now.
991 // If you get an error here, you probably made a change in the JDK library that has added
992 // these objects that are referenced (directly or indirectly) by static fields.
993 ResourceMark rm;
994 log_error(cds, heap)("Cannot archive object of class %s", orig_obj->klass()->external_name());
995 vm_direct_exit(1);
996 }
997
998 // java.lang.Class instances cannot be included in an archived object sub-graph. We only support
999 // them as Klass::_archived_mirror because they need to be specially restored at run time.
1000 //
1001 // If you get an error here, you probably made a change in the JDK library that has added a Class
1002 // object that is referenced (directly or indirectly) by static fields.
1003 if (java_lang_Class::is_instance(orig_obj)) {
1004 log_error(cds, heap)("(%d) Unknown java.lang.Class object is in the archived sub-graph", level);
1005 vm_direct_exit(1);
1006 }
1007
1008 oop archived_obj = find_archived_heap_object(orig_obj);
1009 if (java_lang_String::is_instance(orig_obj) && archived_obj != NULL) {
1010 // To save time, don't walk strings that are already archived. They just contain
1011 // pointers to a type array, whose klass doesn't need to be recorded.
1012 return archived_obj;
1013 }
1014
1015 if (has_been_seen_during_subgraph_recording(orig_obj)) {
1016 // orig_obj has already been archived and traced. Nothing more to do.
1017 return archived_obj;
1018 } else {
1019 set_has_been_seen_during_subgraph_recording(orig_obj);
1020 }
1021
1022 bool record_klasses_only = (archived_obj != NULL);
1023 if (archived_obj == NULL) {
1024 ++_num_new_archived_objs;
1025 archived_obj = archive_object(orig_obj);
1026 if (archived_obj == NULL) {
1027 // Skip archiving the sub-graph referenced from the current entry field.
1028 ResourceMark rm;
1029 log_error(cds, heap)(
1030 "Cannot archive the sub-graph referenced from %s object ("
1031 PTR_FORMAT ") size " SIZE_FORMAT ", skipped.",
1032 orig_obj->klass()->external_name(), p2i(orig_obj), orig_obj->size() * HeapWordSize);
1033 if (level == 1) {
1034 // Don't archive a subgraph root that's too big. For archives static fields, that's OK
1035 // as the Java code will take care of initializing this field dynamically.
1036 return NULL;
1037 } else {
1038 // We don't know how to handle an object that has been archived, but some of its reachable
1039 // objects cannot be archived. Bail out for now. We might need to fix this in the future if
1040 // we have a real use case.
1041 vm_direct_exit(1);
1042 }
1043 }
1044
1045 if (java_lang_Module::is_instance(orig_obj)) {
1046 check_module_oop(orig_obj);
1047 java_lang_Module::set_module_entry(archived_obj, NULL);
1048 java_lang_Module::set_loader(archived_obj, NULL);
1049 } else if (java_lang_ClassLoader::is_instance(orig_obj)) {
1050 // class_data will be restored explicitly at run time.
1051 guarantee(orig_obj == SystemDictionary::java_platform_loader() ||
1052 orig_obj == SystemDictionary::java_system_loader() ||
1053 java_lang_ClassLoader::loader_data(orig_obj) == NULL, "must be");
1054 java_lang_ClassLoader::release_set_loader_data(archived_obj, NULL);
1055 }
1056 }
1057
1058 assert(archived_obj != NULL, "must be");
1059 Klass *orig_k = orig_obj->klass();
1060 subgraph_info->add_subgraph_object_klass(orig_k);
1061
1062 WalkOopAndArchiveClosure walker(level, is_closed_archive, record_klasses_only,
1063 subgraph_info, orig_obj, archived_obj);
1064 orig_obj->oop_iterate(&walker);
1065 if (is_closed_archive && orig_k->is_instance_klass()) {
1066 check_closed_region_object(InstanceKlass::cast(orig_k));
1067 }
1068 return archived_obj;
1069 }
1070
1071 //
1072 // Start from the given static field in a java mirror and archive the
1073 // complete sub-graph of java heap objects that are reached directly
1074 // or indirectly from the starting object by following references.
1075 // Sub-graph archiving restrictions (current):
1076 //
1077 // - All classes of objects in the archived sub-graph (including the
1078 // entry class) must be boot class only.
1079 // - No java.lang.Class instance (java mirror) can be included inside
1080 // an archived sub-graph. Mirror can only be the sub-graph entry object.
1081 //
1082 // The Java heap object sub-graph archiving process (see
1083 // WalkOopAndArchiveClosure):
1084 //
1085 // 1) Java object sub-graph archiving starts from a given static field
1086 // within a Class instance (java mirror). If the static field is a
1087 // refererence field and points to a non-null java object, proceed to
1088 // the next step.
1089 //
1090 // 2) Archives the referenced java object. If an archived copy of the
1091 // current object already exists, updates the pointer in the archived
1092 // copy of the referencing object to point to the current archived object.
1093 // Otherwise, proceed to the next step.
1094 //
1095 // 3) Follows all references within the current java object and recursively
1096 // archive the sub-graph of objects starting from each reference.
1097 //
1098 // 4) Updates the pointer in the archived copy of referencing object to
1099 // point to the current archived object.
1100 //
1101 // 5) The Klass of the current java object is added to the list of Klasses
1102 // for loading and initialzing before any object in the archived graph can
1103 // be accessed at runtime.
1104 //
1105 void HeapShared::archive_reachable_objects_from_static_field(InstanceKlass *k,
1106 const char* klass_name,
1107 int field_offset,
1108 const char* field_name,
1109 bool is_closed_archive) {
1110 assert(DumpSharedSpaces, "dump time only");
1111 assert(k->is_shared_boot_class(), "must be boot class");
1112
1113 oop m = k->java_mirror();
1114
1115 KlassSubGraphInfo* subgraph_info = get_subgraph_info(k);
1116 oop f = m->obj_field(field_offset);
1117
1118 log_debug(cds, heap)("Start archiving from: %s::%s (" PTR_FORMAT ")", klass_name, field_name, p2i(f));
1119
1120 if (!CompressedOops::is_null(f)) {
1121 if (log_is_enabled(Trace, cds, heap)) {
1122 LogTarget(Trace, cds, heap) log;
1123 LogStream out(log);
1124 f->print_on(&out);
1125 }
1126
1127 oop af = archive_reachable_objects_from(1, subgraph_info, f, is_closed_archive);
1128
1129 if (af == NULL) {
1130 log_error(cds, heap)("Archiving failed %s::%s (some reachable objects cannot be archived)",
1131 klass_name, field_name);
1132 } else {
1133 // Note: the field value is not preserved in the archived mirror.
1134 // Record the field as a new subGraph entry point. The recorded
1135 // information is restored from the archive at runtime.
1136 subgraph_info->add_subgraph_entry_field(field_offset, af, is_closed_archive);
1137 log_info(cds, heap)("Archived field %s::%s => " PTR_FORMAT, klass_name, field_name, p2i(af));
1138 }
1139 } else {
1140 // The field contains null, we still need to record the entry point,
1141 // so it can be restored at runtime.
1142 subgraph_info->add_subgraph_entry_field(field_offset, NULL, false);
1143 }
1144 }
1145
1146 #ifndef PRODUCT
1147 class VerifySharedOopClosure: public BasicOopIterateClosure {
1148 private:
1149 bool _is_archived;
1150
1151 public:
1152 VerifySharedOopClosure(bool is_archived) : _is_archived(is_archived) {}
1153
1154 void do_oop(narrowOop *p) { VerifySharedOopClosure::do_oop_work(p); }
1155 void do_oop( oop *p) { VerifySharedOopClosure::do_oop_work(p); }
1156
1157 protected:
1158 template <class T> void do_oop_work(T *p) {
1159 oop obj = RawAccess<>::oop_load(p);
1160 if (!CompressedOops::is_null(obj)) {
1161 HeapShared::verify_reachable_objects_from(obj, _is_archived);
1162 }
1163 }
1164 };
1165
1166 void HeapShared::verify_subgraph_from_static_field(InstanceKlass* k, int field_offset) {
1167 assert(DumpSharedSpaces, "dump time only");
1168 assert(k->is_shared_boot_class(), "must be boot class");
1169
1170 oop m = k->java_mirror();
1171 oop f = m->obj_field(field_offset);
1172 if (!CompressedOops::is_null(f)) {
1173 verify_subgraph_from(f);
1174 }
1175 }
1176
1177 void HeapShared::verify_subgraph_from(oop orig_obj) {
1178 oop archived_obj = find_archived_heap_object(orig_obj);
1179 if (archived_obj == NULL) {
1180 // It's OK for the root of a subgraph to be not archived. See comments in
1181 // archive_reachable_objects_from().
1182 return;
1183 }
1184
1185 // Verify that all objects reachable from orig_obj are archived.
1186 init_seen_objects_table();
1187 verify_reachable_objects_from(orig_obj, false);
1188 delete_seen_objects_table();
1189
1190 // Note: we could also verify that all objects reachable from the archived
1191 // copy of orig_obj can only point to archived objects, with:
1192 // init_seen_objects_table();
1193 // verify_reachable_objects_from(archived_obj, true);
1194 // init_seen_objects_table();
1195 // but that's already done in G1HeapVerifier::verify_archive_regions so we
1196 // won't do it here.
1197 }
1198
1199 void HeapShared::verify_reachable_objects_from(oop obj, bool is_archived) {
1200 _num_total_verifications ++;
1201 if (!has_been_seen_during_subgraph_recording(obj)) {
1202 set_has_been_seen_during_subgraph_recording(obj);
1203
1204 if (is_archived) {
1205 assert(is_archived_object_during_dumptime(obj), "must be");
1206 assert(find_archived_heap_object(obj) == NULL, "must be");
1207 } else {
1208 assert(!is_archived_object_during_dumptime(obj), "must be");
1209 assert(find_archived_heap_object(obj) != NULL, "must be");
1210 }
1211
1212 VerifySharedOopClosure walker(is_archived);
1213 obj->oop_iterate(&walker);
1214 }
1215 }
1216 #endif
1217
1218 HeapShared::SeenObjectsTable* HeapShared::_seen_objects_table = NULL;
1219 int HeapShared::_num_new_walked_objs;
1220 int HeapShared::_num_new_archived_objs;
1221 int HeapShared::_num_old_recorded_klasses;
1222
1223 int HeapShared::_num_total_subgraph_recordings = 0;
1224 int HeapShared::_num_total_walked_objs = 0;
1225 int HeapShared::_num_total_archived_objs = 0;
1226 int HeapShared::_num_total_recorded_klasses = 0;
1227 int HeapShared::_num_total_verifications = 0;
1228
1229 bool HeapShared::has_been_seen_during_subgraph_recording(oop obj) {
1230 return _seen_objects_table->get(obj) != NULL;
1231 }
1232
1233 void HeapShared::set_has_been_seen_during_subgraph_recording(oop obj) {
1234 assert(!has_been_seen_during_subgraph_recording(obj), "sanity");
1235 _seen_objects_table->put(obj, true);
1236 ++ _num_new_walked_objs;
1237 }
1238
1239 void HeapShared::start_recording_subgraph(InstanceKlass *k, const char* class_name, bool is_full_module_graph) {
1240 log_info(cds, heap)("Start recording subgraph(s) for archived fields in %s", class_name);
1241 init_subgraph_info(k, is_full_module_graph);
1242 init_seen_objects_table();
1243 _num_new_walked_objs = 0;
1244 _num_new_archived_objs = 0;
1245 _num_old_recorded_klasses = get_subgraph_info(k)->num_subgraph_object_klasses();
1246 }
1247
1248 void HeapShared::done_recording_subgraph(InstanceKlass *k, const char* class_name) {
1249 int num_new_recorded_klasses = get_subgraph_info(k)->num_subgraph_object_klasses() -
1250 _num_old_recorded_klasses;
1251 log_info(cds, heap)("Done recording subgraph(s) for archived fields in %s: "
1252 "walked %d objs, archived %d new objs, recorded %d classes",
1253 class_name, _num_new_walked_objs, _num_new_archived_objs,
1254 num_new_recorded_klasses);
1255
1256 delete_seen_objects_table();
1257
1258 _num_total_subgraph_recordings ++;
1259 _num_total_walked_objs += _num_new_walked_objs;
1260 _num_total_archived_objs += _num_new_archived_objs;
1261 _num_total_recorded_klasses += num_new_recorded_klasses;
1262 }
1263
1264 class ArchivableStaticFieldFinder: public FieldClosure {
1265 InstanceKlass* _ik;
1266 Symbol* _field_name;
1267 bool _found;
1268 int _offset;
1269 public:
1270 ArchivableStaticFieldFinder(InstanceKlass* ik, Symbol* field_name) :
1271 _ik(ik), _field_name(field_name), _found(false), _offset(-1) {}
1272
1273 virtual void do_field(fieldDescriptor* fd) {
1274 if (fd->name() == _field_name) {
1275 assert(!_found, "fields cannot be overloaded");
1276 assert(is_reference_type(fd->field_type()), "can archive only fields that are references");
1277 _found = true;
1278 _offset = fd->offset();
1279 }
1280 }
1281 bool found() { return _found; }
1282 int offset() { return _offset; }
1283 };
1284
1285 void HeapShared::init_subgraph_entry_fields(ArchivableStaticFieldInfo fields[],
1286 int num, TRAPS) {
1287 for (int i = 0; i < num; i++) {
1288 ArchivableStaticFieldInfo* info = &fields[i];
1289 TempNewSymbol klass_name = SymbolTable::new_symbol(info->klass_name);
1290 TempNewSymbol field_name = SymbolTable::new_symbol(info->field_name);
1291
1292 Klass* k = SystemDictionary::resolve_or_fail(klass_name, true, CHECK);
1293 InstanceKlass* ik = InstanceKlass::cast(k);
1294 assert(InstanceKlass::cast(ik)->is_shared_boot_class(),
1295 "Only support boot classes");
1296 ik->initialize(CHECK);
1297
1298 ArchivableStaticFieldFinder finder(ik, field_name);
1299 ik->do_local_static_fields(&finder);
1300 assert(finder.found(), "field must exist");
1301
1302 info->klass = ik;
1303 info->offset = finder.offset();
1304 }
1305 }
1306
1307 void HeapShared::init_subgraph_entry_fields(TRAPS) {
1308 assert(HeapShared::can_write(), "must be");
1309 _dump_time_subgraph_info_table = new (ResourceObj::C_HEAP, mtClass)DumpTimeKlassSubGraphInfoTable();
1310 init_subgraph_entry_fields(closed_archive_subgraph_entry_fields,
1311 num_closed_archive_subgraph_entry_fields,
1312 CHECK);
1313 init_subgraph_entry_fields(open_archive_subgraph_entry_fields,
1314 num_open_archive_subgraph_entry_fields,
1315 CHECK);
1316 if (MetaspaceShared::use_full_module_graph()) {
1317 init_subgraph_entry_fields(fmg_open_archive_subgraph_entry_fields,
1318 num_fmg_open_archive_subgraph_entry_fields,
1319 CHECK);
1320 }
1321 }
1322
1323 void HeapShared::init_for_dumping(TRAPS) {
1324 if (HeapShared::can_write()) {
1325 _dumped_interned_strings = new (ResourceObj::C_HEAP, mtClass)DumpedInternedStrings();
1326 init_subgraph_entry_fields(CHECK);
1327 }
1328 }
1329
1330 void HeapShared::archive_object_subgraphs(ArchivableStaticFieldInfo fields[],
1331 int num, bool is_closed_archive,
1332 bool is_full_module_graph) {
1333 _num_total_subgraph_recordings = 0;
1334 _num_total_walked_objs = 0;
1335 _num_total_archived_objs = 0;
1336 _num_total_recorded_klasses = 0;
1337 _num_total_verifications = 0;
1338
1339 // For each class X that has one or more archived fields:
1340 // [1] Dump the subgraph of each archived field
1341 // [2] Create a list of all the class of the objects that can be reached
1342 // by any of these static fields.
1343 // At runtime, these classes are initialized before X's archived fields
1344 // are restored by HeapShared::initialize_from_archived_subgraph().
1345 int i;
1346 for (i = 0; i < num; ) {
1347 ArchivableStaticFieldInfo* info = &fields[i];
1348 const char* klass_name = info->klass_name;
1349 start_recording_subgraph(info->klass, klass_name, is_full_module_graph);
1350
1351 // If you have specified consecutive fields of the same klass in
1352 // fields[], these will be archived in the same
1353 // {start_recording_subgraph ... done_recording_subgraph} pass to
1354 // save time.
1355 for (; i < num; i++) {
1356 ArchivableStaticFieldInfo* f = &fields[i];
1357 if (f->klass_name != klass_name) {
1358 break;
1359 }
1360
1361 archive_reachable_objects_from_static_field(f->klass, f->klass_name,
1362 f->offset, f->field_name,
1363 is_closed_archive);
1364 }
1365 done_recording_subgraph(info->klass, klass_name);
1366 }
1367
1368 log_info(cds, heap)("Archived subgraph records in %s archive heap region = %d",
1369 is_closed_archive ? "closed" : "open",
1370 _num_total_subgraph_recordings);
1371 log_info(cds, heap)(" Walked %d objects", _num_total_walked_objs);
1372 log_info(cds, heap)(" Archived %d objects", _num_total_archived_objs);
1373 log_info(cds, heap)(" Recorded %d klasses", _num_total_recorded_klasses);
1374
1375 #ifndef PRODUCT
1376 for (int i = 0; i < num; i++) {
1377 ArchivableStaticFieldInfo* f = &fields[i];
1378 verify_subgraph_from_static_field(f->klass, f->offset);
1379 }
1380 log_info(cds, heap)(" Verified %d references", _num_total_verifications);
1381 #endif
1382 }
1383
1384 // Not all the strings in the global StringTable are dumped into the archive, because
1385 // some of those strings may be only referenced by classes that are excluded from
1386 // the archive. We need to explicitly mark the strings that are:
1387 // [1] used by classes that WILL be archived;
1388 // [2] included in the SharedArchiveConfigFile.
1389 void HeapShared::add_to_dumped_interned_strings(oop string) {
1390 assert_at_safepoint(); // DumpedInternedStrings uses raw oops
1391 bool created;
1392 _dumped_interned_strings->put_if_absent(string, true, &created);
1393 }
1394
1395 // At dump-time, find the location of all the non-null oop pointers in an archived heap
1396 // region. This way we can quickly relocate all the pointers without using
1397 // BasicOopIterateClosure at runtime.
1398 class FindEmbeddedNonNullPointers: public BasicOopIterateClosure {
1399 narrowOop* _start;
1400 BitMap *_oopmap;
1401 int _num_total_oops;
1402 int _num_null_oops;
1403 public:
1404 FindEmbeddedNonNullPointers(narrowOop* start, BitMap* oopmap)
1405 : _start(start), _oopmap(oopmap), _num_total_oops(0), _num_null_oops(0) {}
1406
1407 virtual void do_oop(narrowOop* p) {
1408 _num_total_oops ++;
1409 narrowOop v = *p;
1410 if (!CompressedOops::is_null(v)) {
1411 size_t idx = p - _start;
1412 _oopmap->set_bit(idx);
1413 } else {
1414 _num_null_oops ++;
1415 }
1416 }
1417 virtual void do_oop(oop *p) {
1418 ShouldNotReachHere();
1419 }
1420 int num_total_oops() const { return _num_total_oops; }
1421 int num_null_oops() const { return _num_null_oops; }
1422 };
1423
1424 ResourceBitMap HeapShared::calculate_oopmap(MemRegion region) {
1425 assert(UseCompressedOops, "must be");
1426 size_t num_bits = region.byte_size() / sizeof(narrowOop);
1427 ResourceBitMap oopmap(num_bits);
1428
1429 HeapWord* p = region.start();
1430 HeapWord* end = region.end();
1431 FindEmbeddedNonNullPointers finder((narrowOop*)p, &oopmap);
1432 ArchiveBuilder* builder = DumpSharedSpaces ? ArchiveBuilder::current() : NULL;
1433
1434 int num_objs = 0;
1435 while (p < end) {
1436 oop o = cast_to_oop(p);
1437 o->oop_iterate(&finder);
1438 p += o->size();
1439 if (DumpSharedSpaces) {
1440 builder->relocate_klass_ptr(o);
1441 }
1442 ++ num_objs;
1443 }
1444
1445 log_info(cds, heap)("calculate_oopmap: objects = %6d, embedded oops = %7d, nulls = %7d",
1446 num_objs, finder.num_total_oops(), finder.num_null_oops());
1447 return oopmap;
1448 }
1449
1450 // Patch all the embedded oop pointers inside an archived heap region,
1451 // to be consistent with the runtime oop encoding.
1452 class PatchEmbeddedPointers: public BitMapClosure {
1453 narrowOop* _start;
1454
1455 public:
1456 PatchEmbeddedPointers(narrowOop* start) : _start(start) {}
1457
1458 bool do_bit(size_t offset) {
1459 narrowOop* p = _start + offset;
1460 narrowOop v = *p;
1461 assert(!CompressedOops::is_null(v), "null oops should have been filtered out at dump time");
1462 oop o = HeapShared::decode_from_archive(v);
1463 RawAccess<IS_NOT_NULL>::oop_store(p, o);
1464 return true;
1465 }
1466 };
1467
1468 // Patch all the non-null pointers that are embedded in the archived heap objects
1469 // in this region
1470 void HeapShared::patch_embedded_pointers(MemRegion region, address oopmap,
1471 size_t oopmap_size_in_bits) {
1472 BitMapView bm((BitMap::bm_word_t*)oopmap, oopmap_size_in_bits);
1473
1474 #ifndef PRODUCT
1475 ResourceMark rm;
1476 ResourceBitMap checkBm = calculate_oopmap(region);
1477 assert(bm.is_same(checkBm), "sanity");
1478 #endif
1479
1480 PatchEmbeddedPointers patcher((narrowOop*)region.start());
1481 bm.iterate(&patcher);
1482 }
1483
1484 // The CDS archive remembers each heap object by its address at dump time, but
1485 // the heap object may be loaded at a different address at run time. This structure is used
1486 // to translate the dump time addresses for all objects in FileMapInfo::space_at(region_index)
1487 // to their runtime addresses.
1488 struct LoadedArchiveHeapRegion {
1489 int _region_index; // index for FileMapInfo::space_at(index)
1490 size_t _region_size; // number of bytes in this region
1491 uintptr_t _dumptime_base; // The dump-time (decoded) address of the first object in this region
1492 intx _runtime_offset; // If an object's dump time address P is within in this region, its
1493 // runtime address is P + _runtime_offset
1494
1495 static int comparator(const void* a, const void* b) {
1496 LoadedArchiveHeapRegion* reg_a = (LoadedArchiveHeapRegion*)a;
1497 LoadedArchiveHeapRegion* reg_b = (LoadedArchiveHeapRegion*)b;
1498 if (reg_a->_dumptime_base < reg_b->_dumptime_base) {
1499 return -1;
1500 } else if (reg_a->_dumptime_base == reg_b->_dumptime_base) {
1501 return 0;
1502 } else {
1503 return 1;
1504 }
1505 }
1506
1507 uintptr_t top() {
1508 return _dumptime_base + _region_size;
1509 }
1510 };
1511
1512 void HeapShared::init_loaded_heap_relocation(LoadedArchiveHeapRegion* loaded_regions,
1513 int num_loaded_regions) {
1514 _dumptime_base_0 = loaded_regions[0]._dumptime_base;
1515 _dumptime_base_1 = loaded_regions[1]._dumptime_base;
1516 _dumptime_base_2 = loaded_regions[2]._dumptime_base;
1517 _dumptime_base_3 = loaded_regions[3]._dumptime_base;
1518 _dumptime_top = loaded_regions[num_loaded_regions-1].top();
1519
1520 _runtime_offset_0 = loaded_regions[0]._runtime_offset;
1521 _runtime_offset_1 = loaded_regions[1]._runtime_offset;
1522 _runtime_offset_2 = loaded_regions[2]._runtime_offset;
1523 _runtime_offset_3 = loaded_regions[3]._runtime_offset;
1524
1525 assert(2 <= num_loaded_regions && num_loaded_regions <= 4, "must be");
1526 if (num_loaded_regions < 4) {
1527 _dumptime_base_3 = UINTPTR_MAX;
1528 }
1529 if (num_loaded_regions < 3) {
1530 _dumptime_base_2 = UINTPTR_MAX;
1531 }
1532 }
1533
1534 bool HeapShared::can_load() {
1535 return Universe::heap()->can_load_archived_objects();
1536 }
1537
1538 template <int NUM_LOADED_REGIONS>
1539 class PatchLoadedRegionPointers: public BitMapClosure {
1540 narrowOop* _start;
1541 intx _offset_0;
1542 intx _offset_1;
1543 intx _offset_2;
1544 intx _offset_3;
1545 uintptr_t _base_0;
1546 uintptr_t _base_1;
1547 uintptr_t _base_2;
1548 uintptr_t _base_3;
1549 uintptr_t _top;
1550
1551 static_assert(MetaspaceShared::max_num_heap_regions == 4, "can't handle more than 4 regions");
1552 static_assert(NUM_LOADED_REGIONS >= 2, "we have at least 2 loaded regions");
1553 static_assert(NUM_LOADED_REGIONS <= 4, "we have at most 4 loaded regions");
1554
1555 public:
1556 PatchLoadedRegionPointers(narrowOop* start, LoadedArchiveHeapRegion* loaded_regions)
1557 : _start(start),
1558 _offset_0(loaded_regions[0]._runtime_offset),
1559 _offset_1(loaded_regions[1]._runtime_offset),
1560 _offset_2(loaded_regions[2]._runtime_offset),
1561 _offset_3(loaded_regions[3]._runtime_offset),
1562 _base_0(loaded_regions[0]._dumptime_base),
1563 _base_1(loaded_regions[1]._dumptime_base),
1564 _base_2(loaded_regions[2]._dumptime_base),
1565 _base_3(loaded_regions[3]._dumptime_base) {
1566 _top = loaded_regions[NUM_LOADED_REGIONS-1].top();
1567 }
1568
1569 bool do_bit(size_t offset) {
1570 narrowOop* p = _start + offset;
1571 narrowOop v = *p;
1572 assert(!CompressedOops::is_null(v), "null oops should have been filtered out at dump time");
1573 uintptr_t o = cast_from_oop<uintptr_t>(HeapShared::decode_from_archive(v));
1574 assert(_base_0 <= o && o < _top, "must be");
1575
1576
1577 // We usually have only 2 regions for the default archive. Use template to avoid unnecessary comparisons.
1578 if (NUM_LOADED_REGIONS > 3 && o >= _base_3) {
1579 o += _offset_3;
1580 } else if (NUM_LOADED_REGIONS > 2 && o >= _base_2) {
1581 o += _offset_2;
1582 } else if (o >= _base_1) {
1583 o += _offset_1;
1584 } else {
1585 o += _offset_0;
1586 }
1587 HeapShared::assert_in_loaded_heap(o);
1588 RawAccess<IS_NOT_NULL>::oop_store(p, cast_to_oop(o));
1589 return true;
1590 }
1591 };
1592
1593 int HeapShared::init_loaded_regions(FileMapInfo* mapinfo, LoadedArchiveHeapRegion* loaded_regions,
1594 MemRegion& archive_space) {
1595 size_t total_bytes = 0;
1596 int num_loaded_regions = 0;
1597 for (int i = MetaspaceShared::first_archive_heap_region;
1598 i <= MetaspaceShared::last_archive_heap_region; i++) {
1599 FileMapRegion* r = mapinfo->space_at(i);
1600 r->assert_is_heap_region();
1601 if (r->used() > 0) {
1602 assert(is_aligned(r->used(), HeapWordSize), "must be");
1603 total_bytes += r->used();
1604 LoadedArchiveHeapRegion* ri = &loaded_regions[num_loaded_regions++];
1605 ri->_region_index = i;
1606 ri->_region_size = r->used();
1607 ri->_dumptime_base = (uintptr_t)mapinfo->start_address_as_decoded_from_archive(r);
1608 }
1609 }
1610
1611 assert(is_aligned(total_bytes, HeapWordSize), "must be");
1612 size_t word_size = total_bytes / HeapWordSize;
1613 HeapWord* buffer = Universe::heap()->allocate_loaded_archive_space(word_size);
1614 if (buffer == nullptr) {
1615 return 0;
1616 }
1617
1618 archive_space = MemRegion(buffer, word_size);
1619 _loaded_heap_bottom = (uintptr_t)archive_space.start();
1620 _loaded_heap_top = _loaded_heap_bottom + total_bytes;
1621
1622 return num_loaded_regions;
1623 }
1624
1625 void HeapShared::sort_loaded_regions(LoadedArchiveHeapRegion* loaded_regions, int num_loaded_regions,
1626 uintptr_t buffer) {
1627 // Find the relocation offset of the pointers in each region
1628 qsort(loaded_regions, num_loaded_regions, sizeof(LoadedArchiveHeapRegion),
1629 LoadedArchiveHeapRegion::comparator);
1630
1631 uintptr_t p = buffer;
1632 for (int i = 0; i < num_loaded_regions; i++) {
1633 // This region will be loaded at p, so all objects inside this
1634 // region will be shifted by ri->offset
1635 LoadedArchiveHeapRegion* ri = &loaded_regions[i];
1636 ri->_runtime_offset = p - ri->_dumptime_base;
1637 p += ri->_region_size;
1638 }
1639 assert(p == _loaded_heap_top, "must be");
1640 }
1641
1642 bool HeapShared::load_regions(FileMapInfo* mapinfo, LoadedArchiveHeapRegion* loaded_regions,
1643 int num_loaded_regions, uintptr_t buffer) {
1644 uintptr_t bitmap_base = (uintptr_t)mapinfo->map_bitmap_region();
1645 uintptr_t load_address = buffer;
1646 for (int i = 0; i < num_loaded_regions; i++) {
1647 LoadedArchiveHeapRegion* ri = &loaded_regions[i];
1648 FileMapRegion* r = mapinfo->space_at(ri->_region_index);
1649
1650 if (!mapinfo->read_region(ri->_region_index, (char*)load_address, r->used(), /* do_commit = */ false)) {
1651 // There's no easy way to free the buffer, so we will fill it with zero later
1652 // in fill_failed_loaded_region(), and it will eventually be GC'ed.
1653 log_warning(cds)("Loading of heap region %d has failed. Archived objects are disabled", i);
1654 _loading_failed = true;
1655 return false;
1656 }
1657 log_info(cds)("Loaded heap region #%d at base " INTPTR_FORMAT " top " INTPTR_FORMAT
1658 " size " SIZE_FORMAT_W(6) " delta " INTX_FORMAT,
1659 ri->_region_index, load_address, load_address + ri->_region_size,
1660 ri->_region_size, ri->_runtime_offset);
1661
1662 uintptr_t oopmap = bitmap_base + r->oopmap_offset();
1663 BitMapView bm((BitMap::bm_word_t*)oopmap, r->oopmap_size_in_bits());
1664
1665 if (num_loaded_regions == 4) {
1666 PatchLoadedRegionPointers<4> patcher((narrowOop*)load_address, loaded_regions);
1667 bm.iterate(&patcher);
1668 } else if (num_loaded_regions == 3) {
1669 PatchLoadedRegionPointers<3> patcher((narrowOop*)load_address, loaded_regions);
1670 bm.iterate(&patcher);
1671 } else {
1672 assert(num_loaded_regions == 2, "must be");
1673 PatchLoadedRegionPointers<2> patcher((narrowOop*)load_address, loaded_regions);
1674 bm.iterate(&patcher);
1675 }
1676
1677 load_address += r->used();
1678 }
1679
1680 return true;
1681 }
1682
1683 bool HeapShared::load_heap_regions(FileMapInfo* mapinfo) {
1684 init_narrow_oop_decoding(mapinfo->narrow_oop_base(), mapinfo->narrow_oop_shift());
1685
1686 LoadedArchiveHeapRegion loaded_regions[MetaspaceShared::max_num_heap_regions];
1687 memset(loaded_regions, 0, sizeof(loaded_regions));
1688
1689 MemRegion archive_space;
1690 int num_loaded_regions = init_loaded_regions(mapinfo, loaded_regions, archive_space);
1691 if (num_loaded_regions <= 0) {
1692 return false;
1693 }
1694 sort_loaded_regions(loaded_regions, num_loaded_regions, (uintptr_t)archive_space.start());
1695 if (!load_regions(mapinfo, loaded_regions, num_loaded_regions, (uintptr_t)archive_space.start())) {
1696 assert(_loading_failed, "must be");
1697 return false;
1698 }
1699
1700 init_loaded_heap_relocation(loaded_regions, num_loaded_regions);
1701 _is_loaded = true;
1702 set_roots(mapinfo->heap_obj_roots());
1703
1704 return true;
1705 }
1706
1707 class VerifyLoadedHeapEmbeddedPointers: public BasicOopIterateClosure {
1708 ResourceHashtable<uintptr_t, bool>* _table;
1709
1710 public:
1711 VerifyLoadedHeapEmbeddedPointers(ResourceHashtable<uintptr_t, bool>* table) : _table(table) {}
1712
1713 virtual void do_oop(narrowOop* p) {
1714 // This should be called before the loaded regions are modified, so all the embedded pointers
1715 // must be NULL, or must point to a valid object in the loaded regions.
1716 narrowOop v = *p;
1717 if (!CompressedOops::is_null(v)) {
1718 oop o = CompressedOops::decode_not_null(v);
1719 uintptr_t u = cast_from_oop<uintptr_t>(o);
1720 HeapShared::assert_in_loaded_heap(u);
1721 guarantee(_table->contains(u), "must point to beginning of object in loaded archived regions");
1722 }
1723 }
1724 virtual void do_oop(oop* p) {
1725 ShouldNotReachHere();
1726 }
1727 };
1728
1729 void HeapShared::finish_initialization() {
1730 if (is_loaded()) {
1731 HeapWord* bottom = (HeapWord*)_loaded_heap_bottom;
1732 HeapWord* top = (HeapWord*)_loaded_heap_top;
1733
1734 MemRegion archive_space = MemRegion(bottom, top);
1735 Universe::heap()->complete_loaded_archive_space(archive_space);
1736 }
1737
1738 if (VerifyArchivedFields <= 0 || !is_loaded()) {
1739 return;
1740 }
1741
1742 log_info(cds, heap)("Verify all oops and pointers in loaded heap");
1743
1744 ResourceMark rm;
1745 ResourceHashtable<uintptr_t, bool> table;
1746 VerifyLoadedHeapEmbeddedPointers verifier(&table);
1747 HeapWord* bottom = (HeapWord*)_loaded_heap_bottom;
1748 HeapWord* top = (HeapWord*)_loaded_heap_top;
1749
1750 for (HeapWord* p = bottom; p < top; ) {
1751 oop o = cast_to_oop(p);
1752 table.put(cast_from_oop<uintptr_t>(o), true);
1753 p += o->size();
1754 }
1755
1756 for (HeapWord* p = bottom; p < top; ) {
1757 oop o = cast_to_oop(p);
1758 o->oop_iterate(&verifier);
1759 p += o->size();
1760 }
1761 }
1762
1763 void HeapShared::fill_failed_loaded_region() {
1764 assert(_loading_failed, "must be");
1765 if (_loaded_heap_bottom != 0) {
1766 assert(_loaded_heap_top != 0, "must be");
1767 HeapWord* bottom = (HeapWord*)_loaded_heap_bottom;
1768 HeapWord* top = (HeapWord*)_loaded_heap_top;
1769 Universe::heap()->fill_with_objects(bottom, top - bottom);
1770 }
1771 }
1772
1773 #endif // INCLUDE_CDS_JAVA_HEAP