1 /*
2 * Copyright (c) 2019, 2025, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 #include "cds/aotArtifactFinder.hpp"
26 #include "cds/aotClassLinker.hpp"
27 #include "cds/aotClassLocation.hpp"
28 #include "cds/archiveBuilder.hpp"
29 #include "cds/archiveHeapWriter.hpp"
30 #include "cds/archiveUtils.inline.hpp"
31 #include "cds/cds_globals.hpp"
32 #include "cds/cdsConfig.hpp"
33 #include "cds/dynamicArchive.hpp"
34 #include "cds/lambdaProxyClassDictionary.hpp"
35 #include "cds/lambdaFormInvokers.hpp"
36 #include "cds/metaspaceShared.hpp"
37 #include "cds/regeneratedClasses.hpp"
38 #include "classfile/classLoader.hpp"
39 #include "classfile/classLoaderData.inline.hpp"
40 #include "classfile/symbolTable.hpp"
41 #include "classfile/systemDictionaryShared.hpp"
42 #include "classfile/vmSymbols.hpp"
43 #include "gc/shared/collectedHeap.hpp"
44 #include "gc/shared/gcVMOperations.hpp"
45 #include "gc/shared/gc_globals.hpp"
46 #include "jvm.h"
47 #include "logging/log.hpp"
48 #include "memory/metaspaceClosure.hpp"
49 #include "memory/resourceArea.hpp"
50 #include "oops/klass.inline.hpp"
51 #include "runtime/arguments.hpp"
52 #include "runtime/os.hpp"
53 #include "runtime/sharedRuntime.hpp"
54 #include "runtime/vmOperations.hpp"
55 #include "runtime/vmThread.hpp"
56 #include "utilities/align.hpp"
57 #include "utilities/bitMap.inline.hpp"
58
59
60 class DynamicArchiveBuilder : public ArchiveBuilder {
61 const char* _archive_name;
62 public:
63 DynamicArchiveBuilder(const char* archive_name) : _archive_name(archive_name) {}
64 void mark_pointer(address* ptr_loc) {
65 ArchivePtrMarker::mark_pointer(ptr_loc);
66 }
67
68 static int dynamic_dump_method_comparator(Method* a, Method* b) {
69 Symbol* a_name = a->name();
70 Symbol* b_name = b->name();
71
72 if (a_name == b_name) {
73 return 0;
74 }
75
76 u4 a_offset = ArchiveBuilder::current()->any_to_offset_u4(a_name);
77 u4 b_offset = ArchiveBuilder::current()->any_to_offset_u4(b_name);
78
79 if (a_offset < b_offset) {
80 return -1;
81 } else {
82 assert(a_offset > b_offset, "must be");
83 return 1;
84 }
85 }
86
87 public:
88 DynamicArchiveHeader *_header;
89
90 void init_header();
91 void release_header();
92 void post_dump();
93 void sort_methods();
94 void sort_methods(InstanceKlass* ik) const;
95 void remark_pointers_for_instance_klass(InstanceKlass* k, bool should_mark) const;
96 void write_archive(char* serialized_data, AOTClassLocationConfig* cl_config);
97 void gather_array_klasses();
98
99 public:
100 // Do this before and after the archive dump to see if any corruption
101 // is caused by dynamic dumping.
102 void verify_universe(const char* info) {
103 if (VerifyBeforeExit) {
104 log_info(cds)("Verify %s", info);
105 // Among other things, this ensures that Eden top is correct.
106 Universe::heap()->prepare_for_verify();
107 Universe::verify(info);
108 }
109 }
110
111 void doit() {
112 verify_universe("Before CDS dynamic dump");
113 DEBUG_ONLY(SystemDictionaryShared::NoClassLoadingMark nclm);
114
115 // Block concurrent class unloading from changing the _dumptime_table
116 MutexLocker ml(DumpTimeTable_lock, Mutex::_no_safepoint_check_flag);
117
118 if (SystemDictionaryShared::is_dumptime_table_empty()) {
119 log_warning(cds, dynamic)("There is no class to be included in the dynamic archive.");
120 return;
121 }
122
123 log_info(cds,dynamic)("CDS dynamic dump: clinit = " JLONG_FORMAT "ms)",
124 ClassLoader::class_init_time_ms());
125
126 init_header();
127 gather_source_objs();
128 gather_array_klasses();
129 reserve_buffer();
130
131 log_info(cds, dynamic)("Copying %d klasses and %d symbols",
132 klasses()->length(), symbols()->length());
133 dump_rw_metadata();
134 dump_ro_metadata();
135 relocate_metaspaceobj_embedded_pointers();
136
137 sort_methods();
138
139 log_info(cds)("Make classes shareable");
140 make_klasses_shareable();
141
142 char* serialized_data;
143 AOTClassLocationConfig* cl_config;
144 {
145 // Write the symbol table and system dictionaries to the RO space.
146 // Note that these tables still point to the *original* objects, so
147 // they would need to call DynamicArchive::original_to_target() to
148 // get the correct addresses.
149 assert(current_dump_region() == ro_region(), "Must be RO space");
150 SymbolTable::write_to_archive(symbols());
151
152 ArchiveBuilder::OtherROAllocMark mark;
153 SystemDictionaryShared::write_to_archive(false);
154 cl_config = AOTClassLocationConfig::dumptime()->write_to_archive();
155 DynamicArchive::dump_array_klasses();
156 AOTClassLinker::write_to_archive();
157
158 serialized_data = ro_region()->top();
159 WriteClosure wc(ro_region());
160 ArchiveBuilder::serialize_dynamic_archivable_items(&wc);
161 }
162
163 if (CDSConfig::is_dumping_lambdas_in_legacy_mode()) {
164 log_info(cds)("Adjust lambda proxy class dictionary");
165 LambdaProxyClassDictionary::adjust_dumptime_table();
166 }
167
168 relocate_to_requested();
169
170 write_archive(serialized_data, cl_config);
171 release_header();
172 DynamicArchive::post_dump();
173
174 post_dump();
175
176 verify_universe("After CDS dynamic dump");
177 }
178
179 virtual void iterate_roots(MetaspaceClosure* it) {
180 AOTArtifactFinder::all_cached_classes_do(it);
181 SystemDictionaryShared::dumptime_classes_do(it);
182 iterate_primitive_array_klasses(it);
183 }
184
185 void iterate_primitive_array_klasses(MetaspaceClosure* it) {
186 for (int i = T_BOOLEAN; i <= T_LONG; i++) {
187 assert(is_java_primitive((BasicType)i), "sanity");
188 Klass* k = Universe::typeArrayKlass((BasicType)i); // this give you "[I", etc
189 assert(MetaspaceShared::is_shared_static((void*)k),
190 "one-dimensional primitive array should be in static archive");
191 ArrayKlass* ak = ArrayKlass::cast(k);
192 while (ak != nullptr && ak->is_shared()) {
193 Klass* next_k = ak->array_klass_or_null();
194 if (next_k != nullptr) {
195 ak = ArrayKlass::cast(next_k);
196 } else {
197 ak = nullptr;
198 }
199 }
200 if (ak != nullptr) {
201 assert(ak->dimension() > 1, "sanity");
202 // this is the lowest dimension that's not in the static archive
203 it->push(&ak);
204 }
205 }
206 }
207 };
208
209 void DynamicArchiveBuilder::init_header() {
210 FileMapInfo* mapinfo = new FileMapInfo(_archive_name, false);
211 assert(FileMapInfo::dynamic_info() == mapinfo, "must be");
212 FileMapInfo* base_info = FileMapInfo::current_info();
213 // header only be available after populate_header
214 mapinfo->populate_header(base_info->core_region_alignment());
215 _header = mapinfo->dynamic_header();
216
217 _header->set_base_header_crc(base_info->crc());
218 for (int i = 0; i < MetaspaceShared::n_regions; i++) {
219 _header->set_base_region_crc(i, base_info->region_crc(i));
220 }
221 }
222
223 void DynamicArchiveBuilder::release_header() {
224 // We temporarily allocated a dynamic FileMapInfo for dumping, which makes it appear we
225 // have mapped a dynamic archive, but we actually have not. We are in a safepoint now.
226 // Let's free it so that if class loading happens after we leave the safepoint, nothing
227 // bad will happen.
228 assert(SafepointSynchronize::is_at_safepoint(), "must be");
229 FileMapInfo *mapinfo = FileMapInfo::dynamic_info();
230 assert(mapinfo != nullptr && _header == mapinfo->dynamic_header(), "must be");
231 delete mapinfo;
232 assert(!DynamicArchive::is_mapped(), "must be");
233 _header = nullptr;
234 }
235
236 void DynamicArchiveBuilder::post_dump() {
237 ArchivePtrMarker::reset_map_and_vs();
238 AOTClassLinker::dispose();
239 }
240
241 void DynamicArchiveBuilder::sort_methods() {
242 InstanceKlass::disable_method_binary_search();
243 for (int i = 0; i < klasses()->length(); i++) {
244 Klass* k = get_buffered_addr(klasses()->at(i));
245 if (k->is_instance_klass()) {
246 sort_methods(InstanceKlass::cast(k));
247 }
248 }
249 }
250
251 // The address order of the copied Symbols may be different than when the original
252 // klasses were created. Re-sort all the tables. See Method::sort_methods().
253 void DynamicArchiveBuilder::sort_methods(InstanceKlass* ik) const {
254 assert(ik != nullptr, "DynamicArchiveBuilder currently doesn't support dumping the base archive");
255 if (MetaspaceShared::is_in_shared_metaspace(ik)) {
256 // We have reached a supertype that's already in the base archive
257 return;
258 }
259 assert(is_in_buffer_space(ik), "method sorting must be done on buffered class, not original class");
260 if (ik->java_mirror() == nullptr) {
261 // null mirror means this class has already been visited and methods are already sorted
262 return;
263 }
264 ik->remove_java_mirror();
265
266 if (log_is_enabled(Debug, cds, dynamic)) {
267 ResourceMark rm;
268 log_debug(cds, dynamic)("sorting methods for " PTR_FORMAT " (" PTR_FORMAT ") %s",
269 p2i(ik), p2i(to_requested(ik)), ik->external_name());
270 }
271
272 // Method sorting may re-layout the [iv]tables, which would change the offset(s)
273 // of the locations in an InstanceKlass that would contain pointers. Let's clear
274 // all the existing pointer marking bits, and re-mark the pointers after sorting.
275 remark_pointers_for_instance_klass(ik, false);
276
277 // Make sure all supertypes have been sorted
278 sort_methods(ik->java_super());
279 Array<InstanceKlass*>* interfaces = ik->local_interfaces();
280 int len = interfaces->length();
281 for (int i = 0; i < len; i++) {
282 sort_methods(interfaces->at(i));
283 }
284
285 #ifdef ASSERT
286 if (ik->methods() != nullptr) {
287 for (int m = 0; m < ik->methods()->length(); m++) {
288 Symbol* name = ik->methods()->at(m)->name();
289 assert(MetaspaceShared::is_in_shared_metaspace(name) || is_in_buffer_space(name), "must be");
290 }
291 }
292 if (ik->default_methods() != nullptr) {
293 for (int m = 0; m < ik->default_methods()->length(); m++) {
294 Symbol* name = ik->default_methods()->at(m)->name();
295 assert(MetaspaceShared::is_in_shared_metaspace(name) || is_in_buffer_space(name), "must be");
296 }
297 }
298 #endif
299
300 Method::sort_methods(ik->methods(), /*set_idnums=*/true, dynamic_dump_method_comparator);
301 if (ik->default_methods() != nullptr) {
302 Method::sort_methods(ik->default_methods(), /*set_idnums=*/false, dynamic_dump_method_comparator);
303 }
304 if (ik->is_linked()) {
305 // If the class has already been linked, we must relayout the i/v tables, whose order depends
306 // on the method sorting order.
307 // If the class is unlinked, we cannot layout the i/v tables yet. This is OK, as the
308 // i/v tables will be initialized at runtime after bytecode verification.
309 ik->vtable().initialize_vtable();
310 ik->itable().initialize_itable();
311 }
312
313 // Set all the pointer marking bits after sorting.
314 remark_pointers_for_instance_klass(ik, true);
315 }
316
317 template<bool should_mark>
318 class PointerRemarker: public MetaspaceClosure {
319 public:
320 virtual bool do_ref(Ref* ref, bool read_only) {
321 if (should_mark) {
322 ArchivePtrMarker::mark_pointer(ref->addr());
323 } else {
324 ArchivePtrMarker::clear_pointer(ref->addr());
325 }
326 return false; // don't recurse
327 }
328 };
329
330 void DynamicArchiveBuilder::remark_pointers_for_instance_klass(InstanceKlass* k, bool should_mark) const {
331 if (should_mark) {
332 PointerRemarker<true> marker;
333 k->metaspace_pointers_do(&marker);
334 marker.finish();
335 } else {
336 PointerRemarker<false> marker;
337 k->metaspace_pointers_do(&marker);
338 marker.finish();
339 }
340 }
341
342 void DynamicArchiveBuilder::write_archive(char* serialized_data, AOTClassLocationConfig* cl_config) {
343 _header->set_class_location_config(cl_config);
344 _header->set_serialized_data(serialized_data);
345
346 FileMapInfo* dynamic_info = FileMapInfo::dynamic_info();
347 assert(dynamic_info != nullptr, "Sanity");
348
349 dynamic_info->open_as_output();
350 ArchiveHeapInfo no_heap_for_dynamic_dump;
351 ArchiveBuilder::write_archive(dynamic_info, &no_heap_for_dynamic_dump);
352
353 address base = _requested_dynamic_archive_bottom;
354 address top = _requested_dynamic_archive_top;
355 size_t file_size = pointer_delta(top, base, sizeof(char));
356
357 log_info(cds, dynamic)("Written dynamic archive " PTR_FORMAT " - " PTR_FORMAT
358 " [" UINT32_FORMAT " bytes header, %zu bytes total]",
359 p2i(base), p2i(top), _header->header_size(), file_size);
360
361 log_info(cds, dynamic)("%d klasses; %d symbols", klasses()->length(), symbols()->length());
362 }
363
364 void DynamicArchiveBuilder::gather_array_klasses() {
365 for (int i = 0; i < klasses()->length(); i++) {
366 if (klasses()->at(i)->is_objArray_klass()) {
367 ObjArrayKlass* oak = ObjArrayKlass::cast(klasses()->at(i));
368 Klass* elem = oak->element_klass();
369 if (MetaspaceShared::is_shared_static(elem)) {
370 // Only capture the array klass whose element_klass is in the static archive.
371 // During run time, setup (see DynamicArchive::setup_array_klasses()) is needed
372 // so that the element_klass can find its array klasses from the dynamic archive.
373 DynamicArchive::append_array_klass(oak);
374 } else {
375 // The element_klass and its array klasses are in the same archive.
376 assert(!MetaspaceShared::is_shared_static(oak),
377 "we should not gather klasses that are already in the static archive");
378 }
379 }
380 }
381 log_debug(cds)("Total array klasses gathered for dynamic archive: %d", DynamicArchive::num_array_klasses());
382 }
383
384 class VM_PopulateDynamicDumpSharedSpace: public VM_GC_Sync_Operation {
385 DynamicArchiveBuilder _builder;
386 public:
387 VM_PopulateDynamicDumpSharedSpace(const char* archive_name)
388 : VM_GC_Sync_Operation(), _builder(archive_name) {}
389 VMOp_Type type() const { return VMOp_PopulateDumpSharedSpace; }
390 void doit() {
391 ResourceMark rm;
392 if (AllowArchivingWithJavaAgent) {
393 log_warning(cds)("This %s was created with AllowArchivingWithJavaAgent. It should be used "
394 "for testing purposes only and should not be used in a production environment",
395 CDSConfig::type_of_archive_being_loaded());
396 }
397 AOTClassLocationConfig::dumptime_check_nonempty_dirs();
398 _builder.doit();
399 }
400 ~VM_PopulateDynamicDumpSharedSpace() {
401 RegeneratedClasses::cleanup();
402 }
403 };
404
405 // _array_klasses and _dynamic_archive_array_klasses only hold the array klasses
406 // which have element klass in the static archive.
407 GrowableArray<ObjArrayKlass*>* DynamicArchive::_array_klasses = nullptr;
408 Array<ObjArrayKlass*>* DynamicArchive::_dynamic_archive_array_klasses = nullptr;
409
410 void DynamicArchive::append_array_klass(ObjArrayKlass* ak) {
411 if (_array_klasses == nullptr) {
412 _array_klasses = new (mtClassShared) GrowableArray<ObjArrayKlass*>(50, mtClassShared);
413 }
414 _array_klasses->append(ak);
415 }
416
417 void DynamicArchive::dump_array_klasses() {
418 assert(CDSConfig::is_dumping_dynamic_archive(), "sanity");
419 if (_array_klasses != nullptr) {
420 ArchiveBuilder* builder = ArchiveBuilder::current();
421 int num_array_klasses = _array_klasses->length();
422 _dynamic_archive_array_klasses =
423 ArchiveBuilder::new_ro_array<ObjArrayKlass*>(num_array_klasses);
424 for (int i = 0; i < num_array_klasses; i++) {
425 builder->write_pointer_in_buffer(_dynamic_archive_array_klasses->adr_at(i), _array_klasses->at(i));
426 }
427 }
428 }
429
430 void DynamicArchive::setup_array_klasses() {
431 if (_dynamic_archive_array_klasses != nullptr) {
432 for (int i = 0; i < _dynamic_archive_array_klasses->length(); i++) {
433 ObjArrayKlass* oak = _dynamic_archive_array_klasses->at(i);
434 assert(!oak->is_typeArray_klass(), "all type array classes must be in static archive");
435
436 Klass* elm = oak->element_klass();
437 assert(MetaspaceShared::is_shared_static((void*)elm), "must be");
438
439 if (elm->is_instance_klass()) {
440 assert(InstanceKlass::cast(elm)->array_klasses() == nullptr, "must be");
441 InstanceKlass::cast(elm)->set_array_klasses(oak);
442 } else {
443 assert(elm->is_array_klass(), "sanity");
444 assert(ArrayKlass::cast(elm)->higher_dimension() == nullptr, "must be");
445 ArrayKlass::cast(elm)->set_higher_dimension(oak);
446 }
447 }
448 log_debug(cds)("Total array klasses read from dynamic archive: %d", _dynamic_archive_array_klasses->length());
449 }
450 }
451
452 void DynamicArchive::serialize_array_klasses(SerializeClosure* soc) {
453 soc->do_ptr(&_dynamic_archive_array_klasses);
454 }
455
456 void DynamicArchive::make_array_klasses_shareable() {
457 if (_array_klasses != nullptr) {
458 int num_array_klasses = _array_klasses->length();
459 for (int i = 0; i < num_array_klasses; i++) {
460 ObjArrayKlass* k = ArchiveBuilder::current()->get_buffered_addr(_array_klasses->at(i));
461 k->remove_unshareable_info();
462 }
463 }
464 }
465
466 void DynamicArchive::post_dump() {
467 if (_array_klasses != nullptr) {
468 delete _array_klasses;
469 _array_klasses = nullptr;
470 }
471 }
472
473 int DynamicArchive::num_array_klasses() {
474 return _array_klasses != nullptr ? _array_klasses->length() : 0;
475 }
476
477 void DynamicArchive::dump_impl(bool jcmd_request, const char* archive_name, TRAPS) {
478 MetaspaceShared::link_shared_classes(CHECK);
479 if (!jcmd_request && CDSConfig::is_dumping_regenerated_lambdaform_invokers()) {
480 LambdaFormInvokers::regenerate_holder_classes(CHECK);
481 }
482
483 VM_PopulateDynamicDumpSharedSpace op(archive_name);
484 VMThread::execute(&op);
485 }
486
487 void DynamicArchive::dump_at_exit(JavaThread* current) {
488 ExceptionMark em(current);
489 ResourceMark rm(current);
490 CDSConfig::DumperThreadMark dumper_thread_mark(current);
491
492 const char* archive_name = CDSConfig::output_archive_path();
493 if (!CDSConfig::is_dumping_dynamic_archive() || archive_name == nullptr) {
494 return;
495 }
496
497 log_info(cds, dynamic)("Preparing for dynamic dump at exit in thread %s", current->name());
498
499 JavaThread* THREAD = current; // For TRAPS processing related to link_shared_classes
500 dump_impl(/*jcmd_request=*/false, archive_name, THREAD);
501 if (HAS_PENDING_EXCEPTION) {
502 // One of the prepatory steps failed
503 oop ex = current->pending_exception();
504 log_error(cds)("Dynamic dump has failed");
505 log_error(cds)("%s: %s", ex->klass()->external_name(),
506 java_lang_String::as_utf8_string(java_lang_Throwable::message(ex)));
507 CLEAR_PENDING_EXCEPTION;
508 CDSConfig::disable_dumping_dynamic_archive(); // Just for good measure
509 }
510 }
511
512 // This is called by "jcmd VM.cds dynamic_dump"
513 void DynamicArchive::dump_for_jcmd(const char* archive_name, TRAPS) {
514 CDSConfig::DumperThreadMark dumper_thread_mark(THREAD);
515 assert(CDSConfig::is_using_archive() && RecordDynamicDumpInfo, "already checked in arguments.cpp");
516 assert(ArchiveClassesAtExit == nullptr, "already checked in arguments.cpp");
517 assert(CDSConfig::is_dumping_dynamic_archive(), "already checked by check_for_dynamic_dump() during VM startup");
518 dump_impl(/*jcmd_request=*/true, archive_name, CHECK);
519 }
520
521 bool DynamicArchive::validate(FileMapInfo* dynamic_info) {
522 assert(!dynamic_info->is_static(), "must be");
523 // Check if the recorded base archive matches with the current one
524 FileMapInfo* base_info = FileMapInfo::current_info();
525 DynamicArchiveHeader* dynamic_header = dynamic_info->dynamic_header();
526
527 // Check the header crc
528 if (dynamic_header->base_header_crc() != base_info->crc()) {
529 log_warning(cds)("Dynamic archive cannot be used: static archive header checksum verification failed.");
530 return false;
531 }
532
533 // Check each space's crc
534 for (int i = 0; i < MetaspaceShared::n_regions; i++) {
535 if (dynamic_header->base_region_crc(i) != base_info->region_crc(i)) {
536 log_warning(cds)("Dynamic archive cannot be used: static archive region #%d checksum verification failed.", i);
537 return false;
538 }
539 }
540
541 return true;
542 }
543
544 void DynamicArchiveHeader::print(outputStream* st) {
545 ResourceMark rm;
546
547 st->print_cr("- base_header_crc: 0x%08x", base_header_crc());
548 for (int i = 0; i < NUM_CDS_REGIONS; i++) {
549 st->print_cr("- base_region_crc[%d]: 0x%08x", i, base_region_crc(i));
550 }
551 }