1 /*
2 * Copyright (c) 2019, 2023, 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/archiveHeapWriter.hpp"
28 #include "cds/archiveUtils.inline.hpp"
29 #include "cds/cds_globals.hpp"
30 #include "cds/cdsConfig.hpp"
31 #include "cds/classPrelinker.hpp"
32 #include "cds/dynamicArchive.hpp"
33 #include "cds/regeneratedClasses.hpp"
34 #include "classfile/classLoaderData.inline.hpp"
35 #include "classfile/symbolTable.hpp"
36 #include "classfile/systemDictionaryShared.hpp"
37 #include "classfile/vmSymbols.hpp"
38 #include "gc/shared/collectedHeap.hpp"
39 #include "gc/shared/gcVMOperations.hpp"
40 #include "gc/shared/gc_globals.hpp"
41 #include "jvm.h"
42 #include "logging/log.hpp"
43 #include "memory/metaspaceClosure.hpp"
44 #include "memory/resourceArea.hpp"
45 #include "oops/klass.inline.hpp"
46 #include "runtime/arguments.hpp"
47 #include "runtime/os.hpp"
48 #include "runtime/sharedRuntime.hpp"
49 #include "runtime/vmThread.hpp"
50 #include "runtime/vmOperations.hpp"
51 #include "utilities/align.hpp"
52 #include "utilities/bitMap.inline.hpp"
53
54
55 class DynamicArchiveBuilder : public ArchiveBuilder {
56 const char* _archive_name;
57 public:
58 DynamicArchiveBuilder(const char* archive_name) : _archive_name(archive_name) {}
59 void mark_pointer(address* ptr_loc) {
60 ArchivePtrMarker::mark_pointer(ptr_loc);
61 }
62
63 static int dynamic_dump_method_comparator(Method* a, Method* b) {
64 Symbol* a_name = a->name();
65 Symbol* b_name = b->name();
66
67 if (a_name == b_name) {
68 return 0;
69 }
70
71 u4 a_offset = ArchiveBuilder::current()->any_to_offset_u4(a_name);
72 u4 b_offset = ArchiveBuilder::current()->any_to_offset_u4(b_name);
73
74 if (a_offset < b_offset) {
75 return -1;
76 } else {
77 assert(a_offset > b_offset, "must be");
78 return 1;
79 }
80 }
81
82 public:
83 DynamicArchiveHeader *_header;
84
85 void init_header();
86 void release_header();
87 void post_dump();
88 void sort_methods();
89 void sort_methods(InstanceKlass* ik) const;
90 void remark_pointers_for_instance_klass(InstanceKlass* k, bool should_mark) const;
91 void write_archive(char* serialized_data);
92 void gather_array_klasses();
93
94 public:
95 DynamicArchiveBuilder() : ArchiveBuilder() { }
96
97 // Do this before and after the archive dump to see if any corruption
98 // is caused by dynamic dumping.
99 void verify_universe(const char* info) {
100 if (VerifyBeforeExit) {
101 log_info(cds)("Verify %s", info);
102 // Among other things, this ensures that Eden top is correct.
103 Universe::heap()->prepare_for_verify();
104 Universe::verify(info);
105 }
106 }
107
108 void doit() {
109 verify_universe("Before CDS dynamic dump");
110 DEBUG_ONLY(SystemDictionaryShared::NoClassLoadingMark nclm);
111
112 // Block concurrent class unloading from changing the _dumptime_table
113 MutexLocker ml(DumpTimeTable_lock, Mutex::_no_safepoint_check_flag);
114 SystemDictionaryShared::check_excluded_classes();
115
116 if (SystemDictionaryShared::is_dumptime_table_empty()) {
117 log_warning(cds, dynamic)("There is no class to be included in the dynamic archive.");
118 return;
119 }
120
121 init_header();
122 gather_source_objs();
123 gather_array_klasses();
124 reserve_buffer();
125
126 log_info(cds, dynamic)("Copying %d klasses and %d symbols",
127 klasses()->length(), symbols()->length());
128 dump_rw_metadata();
129 dump_ro_metadata();
130 relocate_metaspaceobj_embedded_pointers();
131
132 verify_estimate_size(_estimated_metaspaceobj_bytes, "MetaspaceObjs");
133
134 char* serialized_data;
135 {
136 // Write the symbol table and system dictionaries to the RO space.
137 // Note that these tables still point to the *original* objects, so
138 // they would need to call DynamicArchive::original_to_target() to
139 // get the correct addresses.
140 assert(current_dump_region() == ro_region(), "Must be RO space");
141 SymbolTable::write_to_archive(symbols());
142
143 ArchiveBuilder::OtherROAllocMark mark;
144 SystemDictionaryShared::write_to_archive(false);
145 DynamicArchive::dump_array_klasses();
146
147 serialized_data = ro_region()->top();
148 WriteClosure wc(ro_region());
149 ArchiveBuilder::serialize_dynamic_archivable_items(&wc);
150 }
151
152 verify_estimate_size(_estimated_hashtable_bytes, "Hashtables");
153
154 sort_methods();
155
156 log_info(cds)("Make classes shareable");
157 make_klasses_shareable();
158
159 log_info(cds)("Adjust lambda proxy class dictionary");
160 SystemDictionaryShared::adjust_lambda_proxy_class_dictionary();
161
162 relocate_to_requested();
163
164 write_archive(serialized_data);
165 release_header();
166 DynamicArchive::post_dump();
167
168 post_dump();
169
170 assert(_num_dump_regions_used == _total_dump_regions, "must be");
171 verify_universe("After CDS dynamic dump");
172 }
173
174 virtual void iterate_roots(MetaspaceClosure* it) {
175 FileMapInfo::metaspace_pointers_do(it);
176 SystemDictionaryShared::dumptime_classes_do(it);
177 iterate_primitive_array_klasses(it);
178 }
179
180 void iterate_primitive_array_klasses(MetaspaceClosure* it) {
181 for (int i = T_BOOLEAN; i <= T_LONG; i++) {
182 assert(is_java_primitive((BasicType)i), "sanity");
183 Klass* k = Universe::typeArrayKlass((BasicType)i); // this give you "[I", etc
184 assert(MetaspaceShared::is_shared_static((void*)k),
185 "one-dimensional primitive array should be in static archive");
186 ArrayKlass* ak = ArrayKlass::cast(k);
187 while (ak != nullptr && ak->is_shared()) {
188 Klass* next_k = ak->array_klass_or_null();
189 if (next_k != nullptr) {
190 ak = ArrayKlass::cast(next_k);
191 } else {
192 ak = nullptr;
193 }
194 }
195 if (ak != nullptr) {
196 assert(ak->dimension() > 1, "sanity");
197 // this is the lowest dimension that's not in the static archive
198 it->push(&ak);
199 }
200 }
201 }
202 };
203
204 void DynamicArchiveBuilder::init_header() {
205 FileMapInfo* mapinfo = new FileMapInfo(_archive_name, false);
206 assert(FileMapInfo::dynamic_info() == mapinfo, "must be");
207 FileMapInfo* base_info = FileMapInfo::current_info();
208 // header only be available after populate_header
209 mapinfo->populate_header(base_info->core_region_alignment());
210 _header = mapinfo->dynamic_header();
211
212 _header->set_base_header_crc(base_info->crc());
213 for (int i = 0; i < MetaspaceShared::n_regions; i++) {
214 _header->set_base_region_crc(i, base_info->region_crc(i));
215 }
216 }
217
218 void DynamicArchiveBuilder::release_header() {
219 // We temporarily allocated a dynamic FileMapInfo for dumping, which makes it appear we
220 // have mapped a dynamic archive, but we actually have not. We are in a safepoint now.
221 // Let's free it so that if class loading happens after we leave the safepoint, nothing
222 // bad will happen.
223 assert(SafepointSynchronize::is_at_safepoint(), "must be");
224 FileMapInfo *mapinfo = FileMapInfo::dynamic_info();
225 assert(mapinfo != nullptr && _header == mapinfo->dynamic_header(), "must be");
226 delete mapinfo;
227 assert(!DynamicArchive::is_mapped(), "must be");
228 _header = nullptr;
229 }
230
231 void DynamicArchiveBuilder::post_dump() {
232 ArchivePtrMarker::reset_map_and_vs();
233 ClassPrelinker::dispose();
234 }
235
236 void DynamicArchiveBuilder::sort_methods() {
237 InstanceKlass::disable_method_binary_search();
238 for (int i = 0; i < klasses()->length(); i++) {
239 Klass* k = get_buffered_addr(klasses()->at(i));
240 if (k->is_instance_klass()) {
241 sort_methods(InstanceKlass::cast(k));
242 }
243 }
244 }
245
246 // The address order of the copied Symbols may be different than when the original
247 // klasses were created. Re-sort all the tables. See Method::sort_methods().
248 void DynamicArchiveBuilder::sort_methods(InstanceKlass* ik) const {
249 assert(ik != nullptr, "DynamicArchiveBuilder currently doesn't support dumping the base archive");
250 if (MetaspaceShared::is_in_shared_metaspace(ik)) {
251 // We have reached a supertype that's already in the base archive
252 return;
253 }
254 assert(is_in_buffer_space(ik), "method sorting must be done on buffered class, not original class");
255 if (ik->java_mirror() == nullptr) {
256 // null mirror means this class has already been visited and methods are already sorted
257 return;
258 }
259 ik->remove_java_mirror();
260
261 if (log_is_enabled(Debug, cds, dynamic)) {
262 ResourceMark rm;
263 log_debug(cds, dynamic)("sorting methods for " PTR_FORMAT " (" PTR_FORMAT ") %s",
264 p2i(ik), p2i(to_requested(ik)), ik->external_name());
265 }
266
267 // Method sorting may re-layout the [iv]tables, which would change the offset(s)
268 // of the locations in an InstanceKlass that would contain pointers. Let's clear
269 // all the existing pointer marking bits, and re-mark the pointers after sorting.
270 remark_pointers_for_instance_klass(ik, false);
271
272 // Make sure all supertypes have been sorted
273 sort_methods(ik->java_super());
274 Array<InstanceKlass*>* interfaces = ik->local_interfaces();
275 int len = interfaces->length();
276 for (int i = 0; i < len; i++) {
277 sort_methods(interfaces->at(i));
278 }
279
280 #ifdef ASSERT
281 if (ik->methods() != nullptr) {
282 for (int m = 0; m < ik->methods()->length(); m++) {
283 Symbol* name = ik->methods()->at(m)->name();
284 assert(MetaspaceShared::is_in_shared_metaspace(name) || is_in_buffer_space(name), "must be");
285 }
286 }
287 if (ik->default_methods() != nullptr) {
288 for (int m = 0; m < ik->default_methods()->length(); m++) {
289 Symbol* name = ik->default_methods()->at(m)->name();
290 assert(MetaspaceShared::is_in_shared_metaspace(name) || is_in_buffer_space(name), "must be");
291 }
292 }
293 #endif
294
295 Method::sort_methods(ik->methods(), /*set_idnums=*/true, dynamic_dump_method_comparator);
296 if (ik->default_methods() != nullptr) {
297 Method::sort_methods(ik->default_methods(), /*set_idnums=*/false, dynamic_dump_method_comparator);
298 }
299 if (ik->is_linked()) {
300 // If the class has already been linked, we must relayout the i/v tables, whose order depends
301 // on the method sorting order.
302 // If the class is unlinked, we cannot layout the i/v tables yet. This is OK, as the
303 // i/v tables will be initialized at runtime after bytecode verification.
304 ik->vtable().initialize_vtable();
305 ik->itable().initialize_itable();
306 }
307
308 // Set all the pointer marking bits after sorting.
309 remark_pointers_for_instance_klass(ik, true);
310 }
311
312 template<bool should_mark>
313 class PointerRemarker: public MetaspaceClosure {
314 public:
315 virtual bool do_ref(Ref* ref, bool read_only) {
316 if (should_mark) {
317 ArchivePtrMarker::mark_pointer(ref->addr());
318 } else {
319 ArchivePtrMarker::clear_pointer(ref->addr());
320 }
321 return false; // don't recurse
322 }
323 };
324
325 void DynamicArchiveBuilder::remark_pointers_for_instance_klass(InstanceKlass* k, bool should_mark) const {
326 if (should_mark) {
327 PointerRemarker<true> marker;
328 k->metaspace_pointers_do(&marker);
329 marker.finish();
330 } else {
331 PointerRemarker<false> marker;
332 k->metaspace_pointers_do(&marker);
333 marker.finish();
334 }
335 }
336
337 void DynamicArchiveBuilder::write_archive(char* serialized_data) {
338 _header->set_shared_path_table(FileMapInfo::shared_path_table().table());
339 _header->set_serialized_data(serialized_data);
340
341 FileMapInfo* dynamic_info = FileMapInfo::dynamic_info();
342 assert(dynamic_info != nullptr, "Sanity");
343
344 dynamic_info->open_for_write();
345 ArchiveHeapInfo no_heap_for_dynamic_dump;
346 ArchiveBuilder::write_archive(dynamic_info, &no_heap_for_dynamic_dump);
347
348 address base = _requested_dynamic_archive_bottom;
349 address top = _requested_dynamic_archive_top;
350 size_t file_size = pointer_delta(top, base, sizeof(char));
351
352 log_info(cds, dynamic)("Written dynamic archive " PTR_FORMAT " - " PTR_FORMAT
353 " [" UINT32_FORMAT " bytes header, " SIZE_FORMAT " bytes total]",
354 p2i(base), p2i(top), _header->header_size(), file_size);
355
356 log_info(cds, dynamic)("%d klasses; %d symbols", klasses()->length(), symbols()->length());
357 }
358
359 void DynamicArchiveBuilder::gather_array_klasses() {
360 for (int i = 0; i < klasses()->length(); i++) {
361 if (klasses()->at(i)->is_objArray_klass()) {
362 ObjArrayKlass* oak = ObjArrayKlass::cast(klasses()->at(i));
363 Klass* elem = oak->element_klass();
364 if (MetaspaceShared::is_shared_static(elem)) {
365 // Only capture the array klass whose element_klass is in the static archive.
366 // During run time, setup (see DynamicArchive::setup_array_klasses()) is needed
367 // so that the element_klass can find its array klasses from the dynamic archive.
368 DynamicArchive::append_array_klass(oak);
369 } else {
370 // The element_klass and its array klasses are in the same archive.
371 assert(!MetaspaceShared::is_shared_static(oak),
372 "we should not gather klasses that are already in the static archive");
373 }
374 }
375 }
376 log_debug(cds)("Total array klasses gathered for dynamic archive: %d", DynamicArchive::num_array_klasses());
377 }
378
379 class VM_PopulateDynamicDumpSharedSpace: public VM_GC_Sync_Operation {
380 DynamicArchiveBuilder _builder;
381 public:
382 VM_PopulateDynamicDumpSharedSpace(const char* archive_name)
383 : VM_GC_Sync_Operation(), _builder(archive_name) {}
384 VMOp_Type type() const { return VMOp_PopulateDumpSharedSpace; }
385 void doit() {
386 ResourceMark rm;
387 if (AllowArchivingWithJavaAgent) {
388 log_warning(cds)("This archive was created with AllowArchivingWithJavaAgent. It should be used "
389 "for testing purposes only and should not be used in a production environment");
390 }
391 FileMapInfo::check_nonempty_dir_in_shared_path_table();
392
393 _builder.doit();
394 }
395 ~VM_PopulateDynamicDumpSharedSpace() {
396 RegeneratedClasses::cleanup();
397 }
398 };
399
400 // _array_klasses and _dynamic_archive_array_klasses only hold the array klasses
401 // which have element klass in the static archive.
402 GrowableArray<ObjArrayKlass*>* DynamicArchive::_array_klasses = nullptr;
403 Array<ObjArrayKlass*>* DynamicArchive::_dynamic_archive_array_klasses = nullptr;
404
405 void DynamicArchive::append_array_klass(ObjArrayKlass* ak) {
406 if (_array_klasses == nullptr) {
407 _array_klasses = new (mtClassShared) GrowableArray<ObjArrayKlass*>(50, mtClassShared);
408 }
409 _array_klasses->append(ak);
410 }
411
412 void DynamicArchive::dump_array_klasses() {
413 assert(CDSConfig::is_dumping_dynamic_archive(), "sanity");
414 if (_array_klasses != nullptr) {
415 ArchiveBuilder* builder = ArchiveBuilder::current();
416 int num_array_klasses = _array_klasses->length();
417 _dynamic_archive_array_klasses =
418 ArchiveBuilder::new_ro_array<ObjArrayKlass*>(num_array_klasses);
419 for (int i = 0; i < num_array_klasses; i++) {
420 builder->write_pointer_in_buffer(_dynamic_archive_array_klasses->adr_at(i), _array_klasses->at(i));
421 }
422 }
423 }
424
425 void DynamicArchive::setup_array_klasses() {
426 if (_dynamic_archive_array_klasses != nullptr) {
427 for (int i = 0; i < _dynamic_archive_array_klasses->length(); i++) {
428 ObjArrayKlass* oak = _dynamic_archive_array_klasses->at(i);
429 assert(!oak->is_typeArray_klass(), "all type array classes must be in static archive");
430
431 Klass* elm = oak->element_klass();
432 assert(MetaspaceShared::is_shared_static((void*)elm), "must be");
433
434 if (elm->is_instance_klass()) {
435 assert(InstanceKlass::cast(elm)->array_klasses() == nullptr, "must be");
436 InstanceKlass::cast(elm)->set_array_klasses(oak);
437 } else {
438 assert(elm->is_array_klass(), "sanity");
439 assert(ArrayKlass::cast(elm)->higher_dimension() == nullptr, "must be");
440 ArrayKlass::cast(elm)->set_higher_dimension(oak);
441 }
442 }
443 log_debug(cds)("Total array klasses read from dynamic archive: %d", _dynamic_archive_array_klasses->length());
444 }
445 }
446
447 void DynamicArchive::serialize_array_klasses(SerializeClosure* soc) {
448 soc->do_ptr(&_dynamic_archive_array_klasses);
449 }
450
451 void DynamicArchive::make_array_klasses_shareable() {
452 if (_array_klasses != nullptr) {
453 int num_array_klasses = _array_klasses->length();
454 for (int i = 0; i < num_array_klasses; i++) {
455 ObjArrayKlass* k = ArchiveBuilder::current()->get_buffered_addr(_array_klasses->at(i));
456 k->remove_unshareable_info();
457 }
458 }
459 }
460
461 void DynamicArchive::post_dump() {
462 if (_array_klasses != nullptr) {
463 delete _array_klasses;
464 _array_klasses = nullptr;
465 }
466 }
467
468 int DynamicArchive::num_array_klasses() {
469 return _array_klasses != nullptr ? _array_klasses->length() : 0;
470 }
471
472 void DynamicArchive::check_for_dynamic_dump() {
473 if (CDSConfig::is_dumping_dynamic_archive() && !UseSharedSpaces) {
474 // This could happen if SharedArchiveFile has failed to load:
475 // - -Xshare:off was specified
476 // - SharedArchiveFile points to an non-existent file.
477 // - SharedArchiveFile points to an archive that has failed CRC check
478 // - SharedArchiveFile is not specified and the VM doesn't have a compatible default archive
479
480 #define __THEMSG " is unsupported when base CDS archive is not loaded. Run with -Xlog:cds for more info."
481 if (RecordDynamicDumpInfo) {
482 log_error(cds)("-XX:+RecordDynamicDumpInfo%s", __THEMSG);
483 MetaspaceShared::unrecoverable_loading_error();
484 } else {
485 assert(ArchiveClassesAtExit != nullptr, "sanity");
486 log_warning(cds)("-XX:ArchiveClassesAtExit" __THEMSG);
487 }
488 #undef __THEMSG
489 CDSConfig::disable_dumping_dynamic_archive();
490 }
491 }
492
493 void DynamicArchive::dump_at_exit(JavaThread* current, const char* archive_name) {
494 ExceptionMark em(current);
495 ResourceMark rm(current);
496
497 if (!CDSConfig::is_dumping_dynamic_archive() || archive_name == nullptr) {
498 return;
499 }
500
501 log_info(cds, dynamic)("Preparing for dynamic dump at exit in thread %s", current->name());
502
503 JavaThread* THREAD = current; // For TRAPS processing related to link_shared_classes
504 MetaspaceShared::link_shared_classes(false/*not from jcmd*/, THREAD);
505 if (!HAS_PENDING_EXCEPTION) {
506 // copy shared path table to saved.
507 if (!HAS_PENDING_EXCEPTION) {
508 VM_PopulateDynamicDumpSharedSpace op(archive_name);
509 VMThread::execute(&op);
510 return;
511 }
512 }
513
514 // One of the prepatory steps failed
515 oop ex = current->pending_exception();
516 log_error(cds)("Dynamic dump has failed");
517 log_error(cds)("%s: %s", ex->klass()->external_name(),
518 java_lang_String::as_utf8_string(java_lang_Throwable::message(ex)));
519 CLEAR_PENDING_EXCEPTION;
520 CDSConfig::disable_dumping_dynamic_archive(); // Just for good measure
521 }
522
523 // This is called by "jcmd VM.cds dynamic_dump"
524 void DynamicArchive::dump_for_jcmd(const char* archive_name, TRAPS) {
525 assert(UseSharedSpaces && RecordDynamicDumpInfo, "already checked in arguments.cpp");
526 assert(ArchiveClassesAtExit == nullptr, "already checked in arguments.cpp");
527 assert(CDSConfig::is_dumping_dynamic_archive(), "already checked by check_for_dynamic_dump() during VM startup");
528 MetaspaceShared::link_shared_classes(true/*from jcmd*/, CHECK);
529 // copy shared path table to saved.
530 VM_PopulateDynamicDumpSharedSpace op(archive_name);
531 VMThread::execute(&op);
532 }
533
534 bool DynamicArchive::validate(FileMapInfo* dynamic_info) {
535 assert(!dynamic_info->is_static(), "must be");
536 // Check if the recorded base archive matches with the current one
537 FileMapInfo* base_info = FileMapInfo::current_info();
538 DynamicArchiveHeader* dynamic_header = dynamic_info->dynamic_header();
539
540 // Check the header crc
541 if (dynamic_header->base_header_crc() != base_info->crc()) {
542 log_warning(cds)("Dynamic archive cannot be used: static archive header checksum verification failed.");
543 return false;
544 }
545
546 // Check each space's crc
547 for (int i = 0; i < MetaspaceShared::n_regions; i++) {
548 if (dynamic_header->base_region_crc(i) != base_info->region_crc(i)) {
549 log_warning(cds)("Dynamic archive cannot be used: static archive region #%d checksum verification failed.", i);
550 return false;
551 }
552 }
553
554 return true;
555 }
556
557 void DynamicArchiveHeader::print(outputStream* st) {
558 ResourceMark rm;
559
560 st->print_cr("- base_header_crc: 0x%08x", base_header_crc());
561 for (int i = 0; i < NUM_CDS_REGIONS; i++) {
562 st->print_cr("- base_region_crc[%d]: 0x%08x", i, base_region_crc(i));
563 }
564 }