1 /* 2 * Copyright (c) 2012, 2018, 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 "jvm.h" 27 #include "classfile/classListParser.hpp" 28 #include "classfile/classLoaderExt.hpp" 29 #include "classfile/dictionary.hpp" 30 #include "classfile/loaderConstraints.hpp" 31 #include "classfile/placeholders.hpp" 32 #include "classfile/sharedClassUtil.hpp" 33 #include "classfile/symbolTable.hpp" 34 #include "classfile/stringTable.hpp" 35 #include "classfile/systemDictionary.hpp" 36 #include "classfile/systemDictionaryShared.hpp" 37 #include "code/codeCache.hpp" 38 #if INCLUDE_ALL_GCS 39 #include "gc/g1/g1Allocator.inline.hpp" 40 #include "gc/g1/g1CollectedHeap.hpp" 41 #endif 42 #include "gc/shared/gcLocker.hpp" 43 #include "interpreter/bytecodeStream.hpp" 44 #include "interpreter/bytecodes.hpp" 45 #include "logging/log.hpp" 46 #include "logging/logMessage.hpp" 47 #include "memory/filemap.hpp" 48 #include "memory/metaspace.hpp" 49 #include "memory/metaspaceShared.hpp" 50 #include "memory/resourceArea.hpp" 51 #include "oops/instanceClassLoaderKlass.hpp" 52 #include "oops/instanceMirrorKlass.hpp" 53 #include "oops/instanceRefKlass.hpp" 54 #include "oops/objArrayKlass.hpp" 55 #include "oops/objArrayOop.hpp" 56 #include "oops/oop.inline.hpp" 57 #include "oops/typeArrayKlass.hpp" 58 #include "prims/jvmtiRedefineClasses.hpp" 59 #include "runtime/timerTrace.hpp" 60 #include "runtime/os.hpp" 61 #include "runtime/signature.hpp" 62 #include "runtime/vmThread.hpp" 63 #include "runtime/vm_operations.hpp" 64 #include "utilities/align.hpp" 65 #include "utilities/defaultStream.hpp" 66 #include "utilities/hashtable.inline.hpp" 67 #include "memory/metaspaceClosure.hpp" 68 69 ReservedSpace MetaspaceShared::_shared_rs; 70 VirtualSpace MetaspaceShared::_shared_vs; 71 MetaspaceSharedStats MetaspaceShared::_stats; 72 bool MetaspaceShared::_has_error_classes; 73 bool MetaspaceShared::_archive_loading_failed = false; 74 bool MetaspaceShared::_remapped_readwrite = false; 75 bool MetaspaceShared::_open_archive_heap_region_mapped = false; 76 address MetaspaceShared::_cds_i2i_entry_code_buffers = NULL; 77 size_t MetaspaceShared::_cds_i2i_entry_code_buffers_size = 0; 78 size_t MetaspaceShared::_core_spaces_size = 0; 79 80 // The CDS archive is divided into the following regions: 81 // mc - misc code (the method entry trampolines) 82 // rw - read-write metadata 83 // ro - read-only metadata and read-only tables 84 // md - misc data (the c++ vtables) 85 // od - optional data (original class files) 86 // 87 // s0 - shared strings(closed archive heap space) #0 88 // s1 - shared strings(closed archive heap space) #1 (may be empty) 89 // oa0 - open archive heap space #0 90 // oa1 - open archive heap space #1 (may be empty) 91 // 92 // The mc, rw, ro, md and od regions are linearly allocated, starting from 93 // SharedBaseAddress, in the order of mc->rw->ro->md->od. The size of these 5 regions 94 // are page-aligned, and there's no gap between any consecutive regions. 95 // 96 // These 5 regions are populated in the following steps: 97 // [1] All classes are loaded in MetaspaceShared::preload_classes(). All metadata are 98 // temporarily allocated outside of the shared regions. Only the method entry 99 // trampolines are written into the mc region. 100 // [2] ArchiveCompactor copies RW metadata into the rw region. 101 // [3] ArchiveCompactor copies RO metadata into the ro region. 102 // [4] SymbolTable, StringTable, SystemDictionary, and a few other read-only data 103 // are copied into the ro region as read-only tables. 104 // [5] C++ vtables are copied into the md region. 105 // [6] Original class files are copied into the od region. 106 // 107 // The s0/s1 and oa0/oa1 regions are populated inside MetaspaceShared::dump_java_heap_objects. 108 // Their layout is independent of the other 5 regions. 109 110 class DumpRegion { 111 private: 112 const char* _name; 113 char* _base; 114 char* _top; 115 char* _end; 116 bool _is_packed; 117 118 char* expand_top_to(char* newtop) { 119 assert(is_allocatable(), "must be initialized and not packed"); 120 assert(newtop >= _top, "must not grow backwards"); 121 if (newtop > _end) { 122 MetaspaceShared::report_out_of_space(_name, newtop - _top); 123 ShouldNotReachHere(); 124 } 125 MetaspaceShared::commit_shared_space_to(newtop); 126 _top = newtop; 127 return _top; 128 } 129 130 public: 131 DumpRegion(const char* name) : _name(name), _base(NULL), _top(NULL), _end(NULL), _is_packed(false) {} 132 133 char* allocate(size_t num_bytes, size_t alignment=BytesPerWord) { 134 char* p = (char*)align_up(_top, alignment); 135 char* newtop = p + align_up(num_bytes, alignment); 136 expand_top_to(newtop); 137 memset(p, 0, newtop - p); 138 return p; 139 } 140 141 void append_intptr_t(intptr_t n) { 142 assert(is_aligned(_top, sizeof(intptr_t)), "bad alignment"); 143 intptr_t *p = (intptr_t*)_top; 144 char* newtop = _top + sizeof(intptr_t); 145 expand_top_to(newtop); 146 *p = n; 147 } 148 149 char* base() const { return _base; } 150 char* top() const { return _top; } 151 char* end() const { return _end; } 152 size_t reserved() const { return _end - _base; } 153 size_t used() const { return _top - _base; } 154 bool is_packed() const { return _is_packed; } 155 bool is_allocatable() const { 156 return !is_packed() && _base != NULL; 157 } 158 159 void print(size_t total_bytes) const { 160 tty->print_cr("%-3s space: " SIZE_FORMAT_W(9) " [ %4.1f%% of total] out of " SIZE_FORMAT_W(9) " bytes [%5.1f%% used] at " INTPTR_FORMAT, 161 _name, used(), percent_of(used(), total_bytes), reserved(), percent_of(used(), reserved()), p2i(_base)); 162 } 163 void print_out_of_space_msg(const char* failing_region, size_t needed_bytes) { 164 tty->print("[%-8s] " PTR_FORMAT " - " PTR_FORMAT " capacity =%9d, allocated =%9d", 165 _name, p2i(_base), p2i(_top), int(_end - _base), int(_top - _base)); 166 if (strcmp(_name, failing_region) == 0) { 167 tty->print_cr(" required = %d", int(needed_bytes)); 168 } else { 169 tty->cr(); 170 } 171 } 172 173 void init(const ReservedSpace* rs) { 174 _base = _top = rs->base(); 175 _end = rs->end(); 176 } 177 void init(char* b, char* t, char* e) { 178 _base = b; 179 _top = t; 180 _end = e; 181 } 182 183 void pack(DumpRegion* next = NULL) { 184 assert(!is_packed(), "sanity"); 185 _end = (char*)align_up(_top, Metaspace::reserve_alignment()); 186 _is_packed = true; 187 if (next != NULL) { 188 next->_base = next->_top = this->_end; 189 next->_end = MetaspaceShared::shared_rs()->end(); 190 } 191 } 192 bool contains(char* p) { 193 return base() <= p && p < top(); 194 } 195 }; 196 197 198 DumpRegion _mc_region("mc"), _ro_region("ro"), _rw_region("rw"), _md_region("md"), _od_region("od"); 199 size_t _total_string_region_size = 0, _total_open_archive_region_size = 0; 200 201 char* MetaspaceShared::misc_code_space_alloc(size_t num_bytes) { 202 return _mc_region.allocate(num_bytes); 203 } 204 205 char* MetaspaceShared::read_only_space_alloc(size_t num_bytes) { 206 return _ro_region.allocate(num_bytes); 207 } 208 209 void MetaspaceShared::initialize_runtime_shared_and_meta_spaces() { 210 assert(UseSharedSpaces, "Must be called when UseSharedSpaces is enabled"); 211 212 // If using shared space, open the file that contains the shared space 213 // and map in the memory before initializing the rest of metaspace (so 214 // the addresses don't conflict) 215 address cds_address = NULL; 216 FileMapInfo* mapinfo = new FileMapInfo(); 217 218 // Open the shared archive file, read and validate the header. If 219 // initialization fails, shared spaces [UseSharedSpaces] are 220 // disabled and the file is closed. 221 // Map in spaces now also 222 if (mapinfo->initialize() && map_shared_spaces(mapinfo)) { 223 size_t cds_total = core_spaces_size(); 224 cds_address = (address)mapinfo->header()->region_addr(0); 225 #ifdef _LP64 226 if (Metaspace::using_class_space()) { 227 char* cds_end = (char*)(cds_address + cds_total); 228 cds_end = (char *)align_up(cds_end, Metaspace::reserve_alignment()); 229 // If UseCompressedClassPointers is set then allocate the metaspace area 230 // above the heap and above the CDS area (if it exists). 231 Metaspace::allocate_metaspace_compressed_klass_ptrs(cds_end, cds_address); 232 // map_heap_regions() compares the current narrow oop and klass encodings 233 // with the archived ones, so it must be done after all encodings are determined. 234 mapinfo->map_heap_regions(); 235 } 236 #endif // _LP64 237 } else { 238 assert(!mapinfo->is_open() && !UseSharedSpaces, 239 "archive file not closed or shared spaces not disabled."); 240 } 241 } 242 243 void MetaspaceShared::initialize_dumptime_shared_and_meta_spaces() { 244 assert(DumpSharedSpaces, "should be called for dump time only"); 245 const size_t reserve_alignment = Metaspace::reserve_alignment(); 246 bool large_pages = false; // No large pages when dumping the CDS archive. 247 char* shared_base = (char*)align_up((char*)SharedBaseAddress, reserve_alignment); 248 249 #ifdef _LP64 250 // On 64-bit VM, the heap and class space layout will be the same as if 251 // you're running in -Xshare:on mode: 252 // 253 // +-- SharedBaseAddress (default = 0x800000000) 254 // v 255 // +-..---------+---------+ ... +----+----+----+----+----+---------------+ 256 // | Heap | Archive | | MC | RW | RO | MD | OD | class space | 257 // +-..---------+---------+ ... +----+----+----+----+----+---------------+ 258 // |<-- MaxHeapSize -->| |<-- UnscaledClassSpaceMax = 4GB ------->| 259 // 260 const uint64_t UnscaledClassSpaceMax = (uint64_t(max_juint) + 1); 261 const size_t cds_total = align_down(UnscaledClassSpaceMax, reserve_alignment); 262 #else 263 // We don't support archives larger than 256MB on 32-bit due to limited virtual address space. 264 size_t cds_total = align_down(256*M, reserve_alignment); 265 #endif 266 267 // First try to reserve the space at the specified SharedBaseAddress. 268 _shared_rs = ReservedSpace(cds_total, reserve_alignment, large_pages, shared_base); 269 if (_shared_rs.is_reserved()) { 270 assert(shared_base == 0 || _shared_rs.base() == shared_base, "should match"); 271 } else { 272 // Get a mmap region anywhere if the SharedBaseAddress fails. 273 _shared_rs = ReservedSpace(cds_total, reserve_alignment, large_pages); 274 } 275 if (!_shared_rs.is_reserved()) { 276 vm_exit_during_initialization("Unable to reserve memory for shared space", 277 err_msg(SIZE_FORMAT " bytes.", cds_total)); 278 } 279 280 #ifdef _LP64 281 // During dump time, we allocate 4GB (UnscaledClassSpaceMax) of space and split it up: 282 // + The upper 1 GB is used as the "temporary compressed class space" -- preload_classes() 283 // will store Klasses into this space. 284 // + The lower 3 GB is used for the archive -- when preload_classes() is done, 285 // ArchiveCompactor will copy the class metadata into this space, first the RW parts, 286 // then the RO parts. 287 288 assert(UseCompressedOops && UseCompressedClassPointers, 289 "UseCompressedOops and UseCompressedClassPointers must be set"); 290 291 size_t max_archive_size = align_down(cds_total * 3 / 4, reserve_alignment); 292 ReservedSpace tmp_class_space = _shared_rs.last_part(max_archive_size); 293 CompressedClassSpaceSize = align_down(tmp_class_space.size(), reserve_alignment); 294 _shared_rs = _shared_rs.first_part(max_archive_size); 295 296 // Set up compress class pointers. 297 Universe::set_narrow_klass_base((address)_shared_rs.base()); 298 // Set narrow_klass_shift to be LogKlassAlignmentInBytes. This is consistent 299 // with AOT. 300 Universe::set_narrow_klass_shift(LogKlassAlignmentInBytes); 301 302 Metaspace::initialize_class_space(tmp_class_space); 303 tty->print_cr("narrow_klass_base = " PTR_FORMAT ", narrow_klass_shift = %d", 304 p2i(Universe::narrow_klass_base()), Universe::narrow_klass_shift()); 305 306 tty->print_cr("Allocated temporary class space: " SIZE_FORMAT " bytes at " PTR_FORMAT, 307 CompressedClassSpaceSize, p2i(tmp_class_space.base())); 308 #endif 309 310 // Start with 0 committed bytes. The memory will be committed as needed by 311 // MetaspaceShared::commit_shared_space_to(). 312 if (!_shared_vs.initialize(_shared_rs, 0)) { 313 vm_exit_during_initialization("Unable to allocate memory for shared space"); 314 } 315 316 _mc_region.init(&_shared_rs); 317 tty->print_cr("Allocated shared space: " SIZE_FORMAT " bytes at " PTR_FORMAT, 318 _shared_rs.size(), p2i(_shared_rs.base())); 319 } 320 321 void MetaspaceShared::commit_shared_space_to(char* newtop) { 322 assert(DumpSharedSpaces, "dump-time only"); 323 char* base = _shared_rs.base(); 324 size_t need_committed_size = newtop - base; 325 size_t has_committed_size = _shared_vs.committed_size(); 326 if (need_committed_size < has_committed_size) { 327 return; 328 } 329 330 size_t min_bytes = need_committed_size - has_committed_size; 331 size_t preferred_bytes = 1 * M; 332 size_t uncommitted = _shared_vs.reserved_size() - has_committed_size; 333 334 size_t commit = MAX2(min_bytes, preferred_bytes); 335 assert(commit <= uncommitted, "sanity"); 336 337 bool result = _shared_vs.expand_by(commit, false); 338 if (!result) { 339 vm_exit_during_initialization(err_msg("Failed to expand shared space to " SIZE_FORMAT " bytes", 340 need_committed_size)); 341 } 342 343 log_info(cds)("Expanding shared spaces by " SIZE_FORMAT_W(7) " bytes [total " SIZE_FORMAT_W(9) " bytes ending at %p]", 344 commit, _shared_vs.actual_committed_size(), _shared_vs.high()); 345 } 346 347 // Read/write a data stream for restoring/preserving metadata pointers and 348 // miscellaneous data from/to the shared archive file. 349 350 void MetaspaceShared::serialize(SerializeClosure* soc) { 351 int tag = 0; 352 soc->do_tag(--tag); 353 354 // Verify the sizes of various metadata in the system. 355 soc->do_tag(sizeof(Method)); 356 soc->do_tag(sizeof(ConstMethod)); 357 soc->do_tag(arrayOopDesc::base_offset_in_bytes(T_BYTE)); 358 soc->do_tag(sizeof(ConstantPool)); 359 soc->do_tag(sizeof(ConstantPoolCache)); 360 soc->do_tag(objArrayOopDesc::base_offset_in_bytes()); 361 soc->do_tag(typeArrayOopDesc::base_offset_in_bytes(T_BYTE)); 362 soc->do_tag(sizeof(Symbol)); 363 364 // Dump/restore miscellaneous metadata. 365 Universe::serialize(soc, true); 366 soc->do_tag(--tag); 367 368 // Dump/restore references to commonly used names and signatures. 369 vmSymbols::serialize(soc); 370 soc->do_tag(--tag); 371 372 // Dump/restore the symbol and string tables 373 SymbolTable::serialize(soc); 374 StringTable::serialize(soc); 375 soc->do_tag(--tag); 376 377 serialize_well_known_classes(soc); 378 soc->do_tag(--tag); 379 380 soc->do_tag(666); 381 } 382 383 void MetaspaceShared::serialize_well_known_classes(SerializeClosure* soc) { 384 java_lang_Class::serialize(soc); 385 java_lang_String::serialize(soc); 386 java_lang_System::serialize(soc); 387 java_lang_ClassLoader::serialize(soc); 388 java_lang_Throwable::serialize(soc); 389 java_lang_Thread::serialize(soc); 390 java_lang_ThreadGroup::serialize(soc); 391 java_lang_AssertionStatusDirectives::serialize(soc); 392 java_lang_ref_SoftReference::serialize(soc); 393 java_lang_invoke_MethodHandle::serialize(soc); 394 java_lang_invoke_DirectMethodHandle::serialize(soc); 395 java_lang_invoke_MemberName::serialize(soc); 396 java_lang_invoke_ResolvedMethodName::serialize(soc); 397 java_lang_invoke_LambdaForm::serialize(soc); 398 java_lang_invoke_MethodType::serialize(soc); 399 java_lang_invoke_CallSite::serialize(soc); 400 java_lang_invoke_MethodHandleNatives_CallSiteContext::serialize(soc); 401 java_security_AccessControlContext::serialize(soc); 402 java_lang_reflect_AccessibleObject::serialize(soc); 403 java_lang_reflect_Method::serialize(soc); 404 java_lang_reflect_Constructor::serialize(soc); 405 java_lang_reflect_Field::serialize(soc); 406 java_nio_Buffer::serialize(soc); 407 reflect_ConstantPool::serialize(soc); 408 reflect_UnsafeStaticFieldAccessorImpl::serialize(soc); 409 java_lang_reflect_Parameter::serialize(soc); 410 java_lang_Module::serialize(soc); 411 java_lang_StackTraceElement::serialize(soc); 412 java_lang_StackFrameInfo::serialize(soc); 413 java_lang_LiveStackFrameInfo::serialize(soc); 414 } 415 416 address MetaspaceShared::cds_i2i_entry_code_buffers(size_t total_size) { 417 if (DumpSharedSpaces) { 418 if (_cds_i2i_entry_code_buffers == NULL) { 419 _cds_i2i_entry_code_buffers = (address)misc_code_space_alloc(total_size); 420 _cds_i2i_entry_code_buffers_size = total_size; 421 } 422 } else if (UseSharedSpaces) { 423 assert(_cds_i2i_entry_code_buffers != NULL, "must already been initialized"); 424 } else { 425 return NULL; 426 } 427 428 assert(_cds_i2i_entry_code_buffers_size == total_size, "must not change"); 429 return _cds_i2i_entry_code_buffers; 430 } 431 432 // CDS code for dumping shared archive. 433 434 // Global object for holding classes that have been loaded. Since this 435 // is run at a safepoint just before exit, this is the entire set of classes. 436 static GrowableArray<Klass*>* _global_klass_objects; 437 438 static void collect_array_classes(Klass* k) { 439 _global_klass_objects->append_if_missing(k); 440 if (k->is_array_klass()) { 441 // Add in the array classes too 442 ArrayKlass* ak = ArrayKlass::cast(k); 443 Klass* h = ak->higher_dimension(); 444 if (h != NULL) { 445 h->array_klasses_do(collect_array_classes); 446 } 447 } 448 } 449 450 class CollectClassesClosure : public KlassClosure { 451 void do_klass(Klass* k) { 452 if (!UseAppCDS && !k->class_loader_data()->is_the_null_class_loader_data()) { 453 // AppCDS is not enabled. Let's omit non-boot classes. 454 return; 455 } 456 457 if (!(k->is_instance_klass() && InstanceKlass::cast(k)->is_in_error_state())) { 458 if (k->is_instance_klass() && InstanceKlass::cast(k)->signers() != NULL) { 459 // Mark any class with signers and don't add to the _global_klass_objects 460 k->set_has_signer_and_not_archived(); 461 } else { 462 _global_klass_objects->append_if_missing(k); 463 } 464 } 465 if (k->is_array_klass()) { 466 // Add in the array classes too 467 ArrayKlass* ak = ArrayKlass::cast(k); 468 Klass* h = ak->higher_dimension(); 469 if (h != NULL) { 470 h->array_klasses_do(collect_array_classes); 471 } 472 } 473 } 474 }; 475 476 static void remove_unshareable_in_classes() { 477 for (int i = 0; i < _global_klass_objects->length(); i++) { 478 Klass* k = _global_klass_objects->at(i); 479 if (!k->is_objArray_klass()) { 480 // InstanceKlass and TypeArrayKlass will in turn call remove_unshareable_info 481 // on their array classes. 482 assert(k->is_instance_klass() || k->is_typeArray_klass(), "must be"); 483 k->remove_unshareable_info(); 484 } 485 } 486 } 487 488 static void remove_java_mirror_in_classes() { 489 for (int i = 0; i < _global_klass_objects->length(); i++) { 490 Klass* k = _global_klass_objects->at(i); 491 if (!k->is_objArray_klass()) { 492 // InstanceKlass and TypeArrayKlass will in turn call remove_unshareable_info 493 // on their array classes. 494 assert(k->is_instance_klass() || k->is_typeArray_klass(), "must be"); 495 k->remove_java_mirror(); 496 } 497 } 498 } 499 500 static void clear_basic_type_mirrors() { 501 assert(!MetaspaceShared::is_heap_object_archiving_allowed(), "Sanity"); 502 Universe::set_int_mirror(NULL); 503 Universe::set_float_mirror(NULL); 504 Universe::set_double_mirror(NULL); 505 Universe::set_byte_mirror(NULL); 506 Universe::set_bool_mirror(NULL); 507 Universe::set_char_mirror(NULL); 508 Universe::set_long_mirror(NULL); 509 Universe::set_short_mirror(NULL); 510 Universe::set_void_mirror(NULL); 511 } 512 513 static void rewrite_nofast_bytecode(Method* method) { 514 BytecodeStream bcs(method); 515 while (!bcs.is_last_bytecode()) { 516 Bytecodes::Code opcode = bcs.next(); 517 switch (opcode) { 518 case Bytecodes::_getfield: *bcs.bcp() = Bytecodes::_nofast_getfield; break; 519 case Bytecodes::_putfield: *bcs.bcp() = Bytecodes::_nofast_putfield; break; 520 case Bytecodes::_aload_0: *bcs.bcp() = Bytecodes::_nofast_aload_0; break; 521 case Bytecodes::_iload: { 522 if (!bcs.is_wide()) { 523 *bcs.bcp() = Bytecodes::_nofast_iload; 524 } 525 break; 526 } 527 default: break; 528 } 529 } 530 } 531 532 // Walk all methods in the class list to ensure that they won't be modified at 533 // run time. This includes: 534 // [1] Rewrite all bytecodes as needed, so that the ConstMethod* will not be modified 535 // at run time by RewriteBytecodes/RewriteFrequentPairs 536 // [2] Assign a fingerprint, so one doesn't need to be assigned at run-time. 537 static void rewrite_nofast_bytecodes_and_calculate_fingerprints() { 538 for (int i = 0; i < _global_klass_objects->length(); i++) { 539 Klass* k = _global_klass_objects->at(i); 540 if (k->is_instance_klass()) { 541 InstanceKlass* ik = InstanceKlass::cast(k); 542 for (int i = 0; i < ik->methods()->length(); i++) { 543 Method* m = ik->methods()->at(i); 544 rewrite_nofast_bytecode(m); 545 Fingerprinter fp(m); 546 // The side effect of this call sets method's fingerprint field. 547 fp.fingerprint(); 548 } 549 } 550 } 551 } 552 553 static void relocate_cached_class_file() { 554 for (int i = 0; i < _global_klass_objects->length(); i++) { 555 Klass* k = _global_klass_objects->at(i); 556 if (k->is_instance_klass()) { 557 InstanceKlass* ik = InstanceKlass::cast(k); 558 JvmtiCachedClassFileData* p = ik->get_archived_class_data(); 559 if (p != NULL) { 560 int size = offset_of(JvmtiCachedClassFileData, data) + p->length; 561 JvmtiCachedClassFileData* q = (JvmtiCachedClassFileData*)_od_region.allocate(size); 562 q->length = p->length; 563 memcpy(q->data, p->data, p->length); 564 ik->set_archived_class_data(q); 565 } 566 } 567 } 568 } 569 570 NOT_PRODUCT( 571 static void assert_not_anonymous_class(InstanceKlass* k) { 572 assert(!(k->is_anonymous()), "cannot archive anonymous classes"); 573 } 574 575 // Anonymous classes are not stored inside any dictionaries. They are created by 576 // SystemDictionary::parse_stream() with a non-null host_klass. 577 static void assert_no_anonymoys_classes_in_dictionaries() { 578 ClassLoaderDataGraph::dictionary_classes_do(assert_not_anonymous_class); 579 }) 580 581 // Objects of the Metadata types (such as Klass and ConstantPool) have C++ vtables. 582 // (In GCC this is the field <Type>::_vptr, i.e., first word in the object.) 583 // 584 // Addresses of the vtables and the methods may be different across JVM runs, 585 // if libjvm.so is dynamically loaded at a different base address. 586 // 587 // To ensure that the Metadata objects in the CDS archive always have the correct vtable: 588 // 589 // + at dump time: we redirect the _vptr to point to our own vtables inside 590 // the CDS image 591 // + at run time: we clone the actual contents of the vtables from libjvm.so 592 // into our own tables. 593 594 // Currently, the archive contain ONLY the following types of objects that have C++ vtables. 595 #define CPP_VTABLE_PATCH_TYPES_DO(f) \ 596 f(ConstantPool) \ 597 f(InstanceKlass) \ 598 f(InstanceClassLoaderKlass) \ 599 f(InstanceMirrorKlass) \ 600 f(InstanceRefKlass) \ 601 f(Method) \ 602 f(ObjArrayKlass) \ 603 f(TypeArrayKlass) 604 605 class CppVtableInfo { 606 intptr_t _vtable_size; 607 intptr_t _cloned_vtable[1]; 608 public: 609 static int num_slots(int vtable_size) { 610 return 1 + vtable_size; // Need to add the space occupied by _vtable_size; 611 } 612 int vtable_size() { return int(uintx(_vtable_size)); } 613 void set_vtable_size(int n) { _vtable_size = intptr_t(n); } 614 intptr_t* cloned_vtable() { return &_cloned_vtable[0]; } 615 void zero() { memset(_cloned_vtable, 0, sizeof(intptr_t) * vtable_size()); } 616 // Returns the address of the next CppVtableInfo that can be placed immediately after this CppVtableInfo 617 static size_t byte_size(int vtable_size) { 618 CppVtableInfo i; 619 return pointer_delta(&i._cloned_vtable[vtable_size], &i, sizeof(u1)); 620 } 621 }; 622 623 template <class T> class CppVtableCloner : public T { 624 static intptr_t* vtable_of(Metadata& m) { 625 return *((intptr_t**)&m); 626 } 627 static CppVtableInfo* _info; 628 629 static int get_vtable_length(const char* name); 630 631 public: 632 // Allocate and initialize the C++ vtable, starting from top, but do not go past end. 633 static intptr_t* allocate(const char* name); 634 635 // Clone the vtable to ... 636 static intptr_t* clone_vtable(const char* name, CppVtableInfo* info); 637 638 static void zero_vtable_clone() { 639 assert(DumpSharedSpaces, "dump-time only"); 640 _info->zero(); 641 } 642 643 // Switch the vtable pointer to point to the cloned vtable. 644 static void patch(Metadata* obj) { 645 assert(DumpSharedSpaces, "dump-time only"); 646 *(void**)obj = (void*)(_info->cloned_vtable()); 647 } 648 649 static bool is_valid_shared_object(const T* obj) { 650 intptr_t* vptr = *(intptr_t**)obj; 651 return vptr == _info->cloned_vtable(); 652 } 653 }; 654 655 template <class T> CppVtableInfo* CppVtableCloner<T>::_info = NULL; 656 657 template <class T> 658 intptr_t* CppVtableCloner<T>::allocate(const char* name) { 659 assert(is_aligned(_md_region.top(), sizeof(intptr_t)), "bad alignment"); 660 int n = get_vtable_length(name); 661 _info = (CppVtableInfo*)_md_region.allocate(CppVtableInfo::byte_size(n), sizeof(intptr_t)); 662 _info->set_vtable_size(n); 663 664 intptr_t* p = clone_vtable(name, _info); 665 assert((char*)p == _md_region.top(), "must be"); 666 667 return p; 668 } 669 670 template <class T> 671 intptr_t* CppVtableCloner<T>::clone_vtable(const char* name, CppVtableInfo* info) { 672 if (!DumpSharedSpaces) { 673 assert(_info == 0, "_info is initialized only at dump time"); 674 _info = info; // Remember it -- it will be used by MetaspaceShared::is_valid_shared_method() 675 } 676 T tmp; // Allocate temporary dummy metadata object to get to the original vtable. 677 int n = info->vtable_size(); 678 intptr_t* srcvtable = vtable_of(tmp); 679 intptr_t* dstvtable = info->cloned_vtable(); 680 681 // We already checked (and, if necessary, adjusted n) when the vtables were allocated, so we are 682 // safe to do memcpy. 683 log_debug(cds, vtables)("Copying %3d vtable entries for %s", n, name); 684 memcpy(dstvtable, srcvtable, sizeof(intptr_t) * n); 685 return dstvtable + n; 686 } 687 688 // To determine the size of the vtable for each type, we use the following 689 // trick by declaring 2 subclasses: 690 // 691 // class CppVtableTesterA: public InstanceKlass {virtual int last_virtual_method() {return 1;} }; 692 // class CppVtableTesterB: public InstanceKlass {virtual void* last_virtual_method() {return NULL}; }; 693 // 694 // CppVtableTesterA and CppVtableTesterB's vtables have the following properties: 695 // - Their size (N+1) is exactly one more than the size of InstanceKlass's vtable (N) 696 // - The first N entries have are exactly the same as in InstanceKlass's vtable. 697 // - Their last entry is different. 698 // 699 // So to determine the value of N, we just walk CppVtableTesterA and CppVtableTesterB's tables 700 // and find the first entry that's different. 701 // 702 // This works on all C++ compilers supported by Oracle, but you may need to tweak it for more 703 // esoteric compilers. 704 705 template <class T> class CppVtableTesterB: public T { 706 public: 707 virtual int last_virtual_method() {return 1;} 708 }; 709 710 template <class T> class CppVtableTesterA : public T { 711 public: 712 virtual void* last_virtual_method() { 713 // Make this different than CppVtableTesterB::last_virtual_method so the C++ 714 // compiler/linker won't alias the two functions. 715 return NULL; 716 } 717 }; 718 719 template <class T> 720 int CppVtableCloner<T>::get_vtable_length(const char* name) { 721 CppVtableTesterA<T> a; 722 CppVtableTesterB<T> b; 723 724 intptr_t* avtable = vtable_of(a); 725 intptr_t* bvtable = vtable_of(b); 726 727 // Start at slot 1, because slot 0 may be RTTI (on Solaris/Sparc) 728 int vtable_len = 1; 729 for (; ; vtable_len++) { 730 if (avtable[vtable_len] != bvtable[vtable_len]) { 731 break; 732 } 733 } 734 log_debug(cds, vtables)("Found %3d vtable entries for %s", vtable_len, name); 735 736 return vtable_len; 737 } 738 739 #define ALLOC_CPP_VTABLE_CLONE(c) \ 740 CppVtableCloner<c>::allocate(#c); 741 742 #define CLONE_CPP_VTABLE(c) \ 743 p = CppVtableCloner<c>::clone_vtable(#c, (CppVtableInfo*)p); 744 745 #define ZERO_CPP_VTABLE(c) \ 746 CppVtableCloner<c>::zero_vtable_clone(); 747 748 // This can be called at both dump time and run time. 749 intptr_t* MetaspaceShared::clone_cpp_vtables(intptr_t* p) { 750 assert(DumpSharedSpaces || UseSharedSpaces, "sanity"); 751 CPP_VTABLE_PATCH_TYPES_DO(CLONE_CPP_VTABLE); 752 return p; 753 } 754 755 void MetaspaceShared::zero_cpp_vtable_clones_for_writing() { 756 assert(DumpSharedSpaces, "dump-time only"); 757 CPP_VTABLE_PATCH_TYPES_DO(ZERO_CPP_VTABLE); 758 } 759 760 // Allocate and initialize the C++ vtables, starting from top, but do not go past end. 761 void MetaspaceShared::allocate_cpp_vtable_clones() { 762 assert(DumpSharedSpaces, "dump-time only"); 763 // Layout (each slot is a intptr_t): 764 // [number of slots in the first vtable = n1] 765 // [ <n1> slots for the first vtable] 766 // [number of slots in the first second = n2] 767 // [ <n2> slots for the second vtable] 768 // ... 769 // The order of the vtables is the same as the CPP_VTAB_PATCH_TYPES_DO macro. 770 CPP_VTABLE_PATCH_TYPES_DO(ALLOC_CPP_VTABLE_CLONE); 771 } 772 773 // Switch the vtable pointer to point to the cloned vtable. We assume the 774 // vtable pointer is in first slot in object. 775 void MetaspaceShared::patch_cpp_vtable_pointers() { 776 int n = _global_klass_objects->length(); 777 for (int i = 0; i < n; i++) { 778 Klass* obj = _global_klass_objects->at(i); 779 if (obj->is_instance_klass()) { 780 InstanceKlass* ik = InstanceKlass::cast(obj); 781 if (ik->is_class_loader_instance_klass()) { 782 CppVtableCloner<InstanceClassLoaderKlass>::patch(ik); 783 } else if (ik->is_reference_instance_klass()) { 784 CppVtableCloner<InstanceRefKlass>::patch(ik); 785 } else if (ik->is_mirror_instance_klass()) { 786 CppVtableCloner<InstanceMirrorKlass>::patch(ik); 787 } else { 788 CppVtableCloner<InstanceKlass>::patch(ik); 789 } 790 ConstantPool* cp = ik->constants(); 791 CppVtableCloner<ConstantPool>::patch(cp); 792 for (int j = 0; j < ik->methods()->length(); j++) { 793 Method* m = ik->methods()->at(j); 794 CppVtableCloner<Method>::patch(m); 795 assert(CppVtableCloner<Method>::is_valid_shared_object(m), "must be"); 796 } 797 } else if (obj->is_objArray_klass()) { 798 CppVtableCloner<ObjArrayKlass>::patch(obj); 799 } else { 800 assert(obj->is_typeArray_klass(), "sanity"); 801 CppVtableCloner<TypeArrayKlass>::patch(obj); 802 } 803 } 804 } 805 806 bool MetaspaceShared::is_valid_shared_method(const Method* m) { 807 assert(is_in_shared_metaspace(m), "must be"); 808 return CppVtableCloner<Method>::is_valid_shared_object(m); 809 } 810 811 // Closure for serializing initialization data out to a data area to be 812 // written to the shared file. 813 814 class WriteClosure : public SerializeClosure { 815 private: 816 DumpRegion* _dump_region; 817 818 public: 819 WriteClosure(DumpRegion* r) { 820 _dump_region = r; 821 } 822 823 void do_ptr(void** p) { 824 _dump_region->append_intptr_t((intptr_t)*p); 825 } 826 827 void do_u4(u4* p) { 828 void* ptr = (void*)(uintx(*p)); 829 do_ptr(&ptr); 830 } 831 832 void do_tag(int tag) { 833 _dump_region->append_intptr_t((intptr_t)tag); 834 } 835 836 void do_oop(oop* o) { 837 if (*o == NULL) { 838 _dump_region->append_intptr_t(0); 839 } else { 840 assert(MetaspaceShared::is_heap_object_archiving_allowed(), 841 "Archiving heap object is not allowed"); 842 _dump_region->append_intptr_t( 843 (intptr_t)oopDesc::encode_heap_oop_not_null(*o)); 844 } 845 } 846 847 void do_region(u_char* start, size_t size) { 848 assert((intptr_t)start % sizeof(intptr_t) == 0, "bad alignment"); 849 assert(size % sizeof(intptr_t) == 0, "bad size"); 850 do_tag((int)size); 851 while (size > 0) { 852 _dump_region->append_intptr_t(*(intptr_t*)start); 853 start += sizeof(intptr_t); 854 size -= sizeof(intptr_t); 855 } 856 } 857 858 bool reading() const { return false; } 859 }; 860 861 // This is for dumping detailed statistics for the allocations 862 // in the shared spaces. 863 class DumpAllocStats : public ResourceObj { 864 public: 865 866 // Here's poor man's enum inheritance 867 #define SHAREDSPACE_OBJ_TYPES_DO(f) \ 868 METASPACE_OBJ_TYPES_DO(f) \ 869 f(SymbolHashentry) \ 870 f(SymbolBucket) \ 871 f(StringHashentry) \ 872 f(StringBucket) \ 873 f(Other) 874 875 enum Type { 876 // Types are MetaspaceObj::ClassType, MetaspaceObj::SymbolType, etc 877 SHAREDSPACE_OBJ_TYPES_DO(METASPACE_OBJ_TYPE_DECLARE) 878 _number_of_types 879 }; 880 881 static const char * type_name(Type type) { 882 switch(type) { 883 SHAREDSPACE_OBJ_TYPES_DO(METASPACE_OBJ_TYPE_NAME_CASE) 884 default: 885 ShouldNotReachHere(); 886 return NULL; 887 } 888 } 889 890 public: 891 enum { RO = 0, RW = 1 }; 892 893 int _counts[2][_number_of_types]; 894 int _bytes [2][_number_of_types]; 895 896 DumpAllocStats() { 897 memset(_counts, 0, sizeof(_counts)); 898 memset(_bytes, 0, sizeof(_bytes)); 899 }; 900 901 void record(MetaspaceObj::Type type, int byte_size, bool read_only) { 902 assert(int(type) >= 0 && type < MetaspaceObj::_number_of_types, "sanity"); 903 int which = (read_only) ? RO : RW; 904 _counts[which][type] ++; 905 _bytes [which][type] += byte_size; 906 } 907 908 void record_other_type(int byte_size, bool read_only) { 909 int which = (read_only) ? RO : RW; 910 _bytes [which][OtherType] += byte_size; 911 } 912 void print_stats(int ro_all, int rw_all, int mc_all, int md_all); 913 }; 914 915 void DumpAllocStats::print_stats(int ro_all, int rw_all, int mc_all, int md_all) { 916 // Calculate size of data that was not allocated by Metaspace::allocate() 917 MetaspaceSharedStats *stats = MetaspaceShared::stats(); 918 919 // symbols 920 _counts[RO][SymbolHashentryType] = stats->symbol.hashentry_count; 921 _bytes [RO][SymbolHashentryType] = stats->symbol.hashentry_bytes; 922 923 _counts[RO][SymbolBucketType] = stats->symbol.bucket_count; 924 _bytes [RO][SymbolBucketType] = stats->symbol.bucket_bytes; 925 926 // strings 927 _counts[RO][StringHashentryType] = stats->string.hashentry_count; 928 _bytes [RO][StringHashentryType] = stats->string.hashentry_bytes; 929 930 _counts[RO][StringBucketType] = stats->string.bucket_count; 931 _bytes [RO][StringBucketType] = stats->string.bucket_bytes; 932 933 // TODO: count things like dictionary, vtable, etc 934 _bytes[RW][OtherType] += mc_all + md_all; 935 rw_all += mc_all + md_all; // mc/md are mapped Read/Write 936 937 // prevent divide-by-zero 938 if (ro_all < 1) { 939 ro_all = 1; 940 } 941 if (rw_all < 1) { 942 rw_all = 1; 943 } 944 945 int all_ro_count = 0; 946 int all_ro_bytes = 0; 947 int all_rw_count = 0; 948 int all_rw_bytes = 0; 949 950 // To make fmt_stats be a syntactic constant (for format warnings), use #define. 951 #define fmt_stats "%-20s: %8d %10d %5.1f | %8d %10d %5.1f | %8d %10d %5.1f" 952 const char *sep = "--------------------+---------------------------+---------------------------+--------------------------"; 953 const char *hdr = " ro_cnt ro_bytes % | rw_cnt rw_bytes % | all_cnt all_bytes %"; 954 955 LogMessage(cds) msg; 956 957 msg.info("Detailed metadata info (excluding od/st regions; rw stats include md/mc regions):"); 958 msg.info("%s", hdr); 959 msg.info("%s", sep); 960 for (int type = 0; type < int(_number_of_types); type ++) { 961 const char *name = type_name((Type)type); 962 int ro_count = _counts[RO][type]; 963 int ro_bytes = _bytes [RO][type]; 964 int rw_count = _counts[RW][type]; 965 int rw_bytes = _bytes [RW][type]; 966 int count = ro_count + rw_count; 967 int bytes = ro_bytes + rw_bytes; 968 969 double ro_perc = percent_of(ro_bytes, ro_all); 970 double rw_perc = percent_of(rw_bytes, rw_all); 971 double perc = percent_of(bytes, ro_all + rw_all); 972 973 msg.info(fmt_stats, name, 974 ro_count, ro_bytes, ro_perc, 975 rw_count, rw_bytes, rw_perc, 976 count, bytes, perc); 977 978 all_ro_count += ro_count; 979 all_ro_bytes += ro_bytes; 980 all_rw_count += rw_count; 981 all_rw_bytes += rw_bytes; 982 } 983 984 int all_count = all_ro_count + all_rw_count; 985 int all_bytes = all_ro_bytes + all_rw_bytes; 986 987 double all_ro_perc = percent_of(all_ro_bytes, ro_all); 988 double all_rw_perc = percent_of(all_rw_bytes, rw_all); 989 double all_perc = percent_of(all_bytes, ro_all + rw_all); 990 991 msg.info("%s", sep); 992 msg.info(fmt_stats, "Total", 993 all_ro_count, all_ro_bytes, all_ro_perc, 994 all_rw_count, all_rw_bytes, all_rw_perc, 995 all_count, all_bytes, all_perc); 996 997 assert(all_ro_bytes == ro_all, "everything should have been counted"); 998 assert(all_rw_bytes == rw_all, "everything should have been counted"); 999 1000 #undef fmt_stats 1001 } 1002 1003 // Populate the shared space. 1004 1005 class VM_PopulateDumpSharedSpace: public VM_Operation { 1006 private: 1007 GrowableArray<MemRegion> *_closed_archive_heap_regions; 1008 GrowableArray<MemRegion> *_open_archive_heap_regions; 1009 1010 void dump_java_heap_objects() NOT_CDS_JAVA_HEAP_RETURN; 1011 void dump_symbols(); 1012 char* dump_read_only_tables(); 1013 void print_region_stats(); 1014 void print_heap_region_stats(GrowableArray<MemRegion> *heap_mem, 1015 const char *name, const size_t total_size); 1016 public: 1017 1018 VMOp_Type type() const { return VMOp_PopulateDumpSharedSpace; } 1019 void doit(); // outline because gdb sucks 1020 static void write_region(FileMapInfo* mapinfo, int region, DumpRegion* space, bool read_only, bool allow_exec); 1021 bool allow_nested_vm_operations() const { return true; } 1022 }; // class VM_PopulateDumpSharedSpace 1023 1024 class SortedSymbolClosure: public SymbolClosure { 1025 GrowableArray<Symbol*> _symbols; 1026 virtual void do_symbol(Symbol** sym) { 1027 assert((*sym)->is_permanent(), "archived symbols must be permanent"); 1028 _symbols.append(*sym); 1029 } 1030 static int compare_symbols_by_address(Symbol** a, Symbol** b) { 1031 if (a[0] < b[0]) { 1032 return -1; 1033 } else if (a[0] == b[0]) { 1034 return 0; 1035 } else { 1036 return 1; 1037 } 1038 } 1039 1040 public: 1041 SortedSymbolClosure() { 1042 SymbolTable::symbols_do(this); 1043 _symbols.sort(compare_symbols_by_address); 1044 } 1045 GrowableArray<Symbol*>* get_sorted_symbols() { 1046 return &_symbols; 1047 } 1048 }; 1049 1050 // ArchiveCompactor -- 1051 // 1052 // This class is the central piece of shared archive compaction -- all metaspace data are 1053 // initially allocated outside of the shared regions. ArchiveCompactor copies the 1054 // metaspace data into their final location in the shared regions. 1055 1056 class ArchiveCompactor : AllStatic { 1057 static DumpAllocStats* _alloc_stats; 1058 static SortedSymbolClosure* _ssc; 1059 1060 static unsigned my_hash(const address& a) { 1061 return primitive_hash<address>(a); 1062 } 1063 static bool my_equals(const address& a0, const address& a1) { 1064 return primitive_equals<address>(a0, a1); 1065 } 1066 typedef ResourceHashtable< 1067 address, address, 1068 ArchiveCompactor::my_hash, // solaris compiler doesn't like: primitive_hash<address> 1069 ArchiveCompactor::my_equals, // solaris compiler doesn't like: primitive_equals<address> 1070 16384, ResourceObj::C_HEAP> RelocationTable; 1071 static RelocationTable* _new_loc_table; 1072 1073 public: 1074 static void initialize() { 1075 _alloc_stats = new(ResourceObj::C_HEAP, mtInternal)DumpAllocStats; 1076 _new_loc_table = new(ResourceObj::C_HEAP, mtInternal)RelocationTable; 1077 } 1078 static DumpAllocStats* alloc_stats() { 1079 return _alloc_stats; 1080 } 1081 1082 static void allocate(MetaspaceClosure::Ref* ref, bool read_only) { 1083 address obj = ref->obj(); 1084 int bytes = ref->size() * BytesPerWord; 1085 char* p; 1086 size_t alignment = BytesPerWord; 1087 char* oldtop; 1088 char* newtop; 1089 1090 if (read_only) { 1091 oldtop = _ro_region.top(); 1092 p = _ro_region.allocate(bytes, alignment); 1093 newtop = _ro_region.top(); 1094 } else { 1095 oldtop = _rw_region.top(); 1096 p = _rw_region.allocate(bytes, alignment); 1097 newtop = _rw_region.top(); 1098 } 1099 memcpy(p, obj, bytes); 1100 bool isnew = _new_loc_table->put(obj, (address)p); 1101 log_trace(cds)("Copy: " PTR_FORMAT " ==> " PTR_FORMAT " %d", p2i(obj), p2i(p), bytes); 1102 assert(isnew, "must be"); 1103 1104 _alloc_stats->record(ref->msotype(), int(newtop - oldtop), read_only); 1105 if (ref->msotype() == MetaspaceObj::SymbolType) { 1106 uintx delta = MetaspaceShared::object_delta(p); 1107 if (delta > MAX_SHARED_DELTA) { 1108 // This is just a sanity check and should not appear in any real world usage. This 1109 // happens only if you allocate more than 2GB of Symbols and would require 1110 // millions of shared classes. 1111 vm_exit_during_initialization("Too many Symbols in the CDS archive", 1112 "Please reduce the number of shared classes."); 1113 } 1114 } 1115 } 1116 1117 static address get_new_loc(MetaspaceClosure::Ref* ref) { 1118 address* pp = _new_loc_table->get(ref->obj()); 1119 assert(pp != NULL, "must be"); 1120 return *pp; 1121 } 1122 1123 private: 1124 // Makes a shallow copy of visited MetaspaceObj's 1125 class ShallowCopier: public UniqueMetaspaceClosure { 1126 bool _read_only; 1127 public: 1128 ShallowCopier(bool read_only) : _read_only(read_only) {} 1129 1130 virtual void do_unique_ref(Ref* ref, bool read_only) { 1131 if (read_only == _read_only) { 1132 allocate(ref, read_only); 1133 } 1134 } 1135 }; 1136 1137 // Relocate embedded pointers within a MetaspaceObj's shallow copy 1138 class ShallowCopyEmbeddedRefRelocator: public UniqueMetaspaceClosure { 1139 public: 1140 virtual void do_unique_ref(Ref* ref, bool read_only) { 1141 address new_loc = get_new_loc(ref); 1142 RefRelocator refer; 1143 ref->metaspace_pointers_do_at(&refer, new_loc); 1144 } 1145 }; 1146 1147 // Relocate a reference to point to its shallow copy 1148 class RefRelocator: public MetaspaceClosure { 1149 public: 1150 virtual bool do_ref(Ref* ref, bool read_only) { 1151 if (ref->not_null()) { 1152 ref->update(get_new_loc(ref)); 1153 } 1154 return false; // Do not recurse. 1155 } 1156 }; 1157 1158 #ifdef ASSERT 1159 class IsRefInArchiveChecker: public MetaspaceClosure { 1160 public: 1161 virtual bool do_ref(Ref* ref, bool read_only) { 1162 if (ref->not_null()) { 1163 char* obj = (char*)ref->obj(); 1164 assert(_ro_region.contains(obj) || _rw_region.contains(obj), 1165 "must be relocated to point to CDS archive"); 1166 } 1167 return false; // Do not recurse. 1168 } 1169 }; 1170 #endif 1171 1172 public: 1173 static void copy_and_compact() { 1174 // We should no longer allocate anything from the metaspace, so that 1175 // we can have a stable set of MetaspaceObjs to work with. 1176 Metaspace::freeze(); 1177 1178 ResourceMark rm; 1179 SortedSymbolClosure the_ssc; // StackObj 1180 _ssc = &the_ssc; 1181 1182 tty->print_cr("Scanning all metaspace objects ... "); 1183 { 1184 // allocate and shallow-copy RW objects, immediately following the MC region 1185 tty->print_cr("Allocating RW objects ... "); 1186 _mc_region.pack(&_rw_region); 1187 1188 ResourceMark rm; 1189 ShallowCopier rw_copier(false); 1190 iterate_roots(&rw_copier); 1191 } 1192 { 1193 // allocate and shallow-copy of RO object, immediately following the RW region 1194 tty->print_cr("Allocating RO objects ... "); 1195 _rw_region.pack(&_ro_region); 1196 1197 ResourceMark rm; 1198 ShallowCopier ro_copier(true); 1199 iterate_roots(&ro_copier); 1200 } 1201 { 1202 tty->print_cr("Relocating embedded pointers ... "); 1203 ResourceMark rm; 1204 ShallowCopyEmbeddedRefRelocator emb_reloc; 1205 iterate_roots(&emb_reloc); 1206 } 1207 { 1208 tty->print_cr("Relocating external roots ... "); 1209 ResourceMark rm; 1210 RefRelocator ext_reloc; 1211 iterate_roots(&ext_reloc); 1212 } 1213 1214 #ifdef ASSERT 1215 { 1216 tty->print_cr("Verifying external roots ... "); 1217 ResourceMark rm; 1218 IsRefInArchiveChecker checker; 1219 iterate_roots(&checker); 1220 } 1221 #endif 1222 1223 1224 // cleanup 1225 _ssc = NULL; 1226 } 1227 1228 // We must relocate the System::_well_known_klasses only after we have copied the 1229 // java objects in during dump_java_heap_objects(): during the object copy, we operate on 1230 // old objects which assert that their klass is the original klass. 1231 static void relocate_well_known_klasses() { 1232 { 1233 tty->print_cr("Relocating SystemDictionary::_well_known_klasses[] ... "); 1234 ResourceMark rm; 1235 RefRelocator ext_reloc; 1236 SystemDictionary::well_known_klasses_do(&ext_reloc); 1237 } 1238 // NOTE: after this point, we shouldn't have any globals that can reach the old 1239 // objects. 1240 1241 // We cannot use any of the objects in the heap anymore (except for the objects 1242 // in the CDS shared string regions) because their headers no longer point to 1243 // valid Klasses. 1244 } 1245 1246 static void iterate_roots(MetaspaceClosure* it) { 1247 GrowableArray<Symbol*>* symbols = _ssc->get_sorted_symbols(); 1248 for (int i=0; i<symbols->length(); i++) { 1249 it->push(symbols->adr_at(i)); 1250 } 1251 if (_global_klass_objects != NULL) { 1252 // Need to fix up the pointers 1253 for (int i = 0; i < _global_klass_objects->length(); i++) { 1254 // NOTE -- this requires that the vtable is NOT yet patched, or else we are hosed. 1255 it->push(_global_klass_objects->adr_at(i)); 1256 } 1257 } 1258 FileMapInfo::metaspace_pointers_do(it); 1259 SystemDictionary::classes_do(it); 1260 Universe::metaspace_pointers_do(it); 1261 SymbolTable::metaspace_pointers_do(it); 1262 vmSymbols::metaspace_pointers_do(it); 1263 } 1264 1265 static Klass* get_relocated_klass(Klass* orig_klass) { 1266 assert(DumpSharedSpaces, "dump time only"); 1267 address* pp = _new_loc_table->get((address)orig_klass); 1268 assert(pp != NULL, "must be"); 1269 Klass* klass = (Klass*)(*pp); 1270 assert(klass->is_klass(), "must be"); 1271 return klass; 1272 } 1273 }; 1274 1275 DumpAllocStats* ArchiveCompactor::_alloc_stats; 1276 SortedSymbolClosure* ArchiveCompactor::_ssc; 1277 ArchiveCompactor::RelocationTable* ArchiveCompactor::_new_loc_table; 1278 1279 void VM_PopulateDumpSharedSpace::write_region(FileMapInfo* mapinfo, int region_idx, 1280 DumpRegion* dump_region, bool read_only, bool allow_exec) { 1281 mapinfo->write_region(region_idx, dump_region->base(), dump_region->used(), read_only, allow_exec); 1282 } 1283 1284 void VM_PopulateDumpSharedSpace::dump_symbols() { 1285 tty->print_cr("Dumping symbol table ..."); 1286 1287 NOT_PRODUCT(SymbolTable::verify()); 1288 SymbolTable::write_to_archive(); 1289 } 1290 1291 char* VM_PopulateDumpSharedSpace::dump_read_only_tables() { 1292 char* oldtop = _ro_region.top(); 1293 // Reorder the system dictionary. Moving the symbols affects 1294 // how the hash table indices are calculated. 1295 SystemDictionary::reorder_dictionary_for_sharing(); 1296 1297 tty->print("Removing java_mirror ... "); 1298 if (!MetaspaceShared::is_heap_object_archiving_allowed()) { 1299 clear_basic_type_mirrors(); 1300 } 1301 remove_java_mirror_in_classes(); 1302 tty->print_cr("done. "); 1303 NOT_PRODUCT(SystemDictionary::verify();) 1304 1305 size_t buckets_bytes = SystemDictionary::count_bytes_for_buckets(); 1306 char* buckets_top = _ro_region.allocate(buckets_bytes, sizeof(intptr_t)); 1307 SystemDictionary::copy_buckets(buckets_top, _ro_region.top()); 1308 1309 size_t table_bytes = SystemDictionary::count_bytes_for_table(); 1310 char* table_top = _ro_region.allocate(table_bytes, sizeof(intptr_t)); 1311 SystemDictionary::copy_table(table_top, _ro_region.top()); 1312 1313 // Write the other data to the output array. 1314 WriteClosure wc(&_ro_region); 1315 MetaspaceShared::serialize(&wc); 1316 1317 char* newtop = _ro_region.top(); 1318 ArchiveCompactor::alloc_stats()->record_other_type(int(newtop - oldtop), true); 1319 return buckets_top; 1320 } 1321 1322 void VM_PopulateDumpSharedSpace::doit() { 1323 Thread* THREAD = VMThread::vm_thread(); 1324 1325 NOT_PRODUCT(SystemDictionary::verify();) 1326 // The following guarantee is meant to ensure that no loader constraints 1327 // exist yet, since the constraints table is not shared. This becomes 1328 // more important now that we don't re-initialize vtables/itables for 1329 // shared classes at runtime, where constraints were previously created. 1330 guarantee(SystemDictionary::constraints()->number_of_entries() == 0, 1331 "loader constraints are not saved"); 1332 guarantee(SystemDictionary::placeholders()->number_of_entries() == 0, 1333 "placeholders are not saved"); 1334 // Revisit and implement this if we prelink method handle call sites: 1335 guarantee(SystemDictionary::invoke_method_table() == NULL || 1336 SystemDictionary::invoke_method_table()->number_of_entries() == 0, 1337 "invoke method table is not saved"); 1338 1339 // At this point, many classes have been loaded. 1340 // Gather systemDictionary classes in a global array and do everything to 1341 // that so we don't have to walk the SystemDictionary again. 1342 _global_klass_objects = new GrowableArray<Klass*>(1000); 1343 CollectClassesClosure collect_classes; 1344 ClassLoaderDataGraph::loaded_classes_do(&collect_classes); 1345 1346 tty->print_cr("Number of classes %d", _global_klass_objects->length()); 1347 { 1348 int num_type_array = 0, num_obj_array = 0, num_inst = 0; 1349 for (int i = 0; i < _global_klass_objects->length(); i++) { 1350 Klass* k = _global_klass_objects->at(i); 1351 if (k->is_instance_klass()) { 1352 num_inst ++; 1353 } else if (k->is_objArray_klass()) { 1354 num_obj_array ++; 1355 } else { 1356 assert(k->is_typeArray_klass(), "sanity"); 1357 num_type_array ++; 1358 } 1359 } 1360 tty->print_cr(" instance classes = %5d", num_inst); 1361 tty->print_cr(" obj array classes = %5d", num_obj_array); 1362 tty->print_cr(" type array classes = %5d", num_type_array); 1363 } 1364 1365 // Ensure the ConstMethods won't be modified at run-time 1366 tty->print("Updating ConstMethods ... "); 1367 rewrite_nofast_bytecodes_and_calculate_fingerprints(); 1368 tty->print_cr("done. "); 1369 1370 // Move classes from platform/system dictionaries into the boot dictionary 1371 SystemDictionary::combine_shared_dictionaries(); 1372 1373 // Remove all references outside the metadata 1374 tty->print("Removing unshareable information ... "); 1375 remove_unshareable_in_classes(); 1376 tty->print_cr("done. "); 1377 1378 // We don't support archiving anonymous classes. Verify that they are not stored in 1379 // the any dictionaries. 1380 NOT_PRODUCT(assert_no_anonymoys_classes_in_dictionaries()); 1381 1382 SystemDictionaryShared::finalize_verification_constraints(); 1383 1384 ArchiveCompactor::initialize(); 1385 ArchiveCompactor::copy_and_compact(); 1386 1387 dump_symbols(); 1388 1389 // Dump supported java heap objects 1390 _closed_archive_heap_regions = NULL; 1391 _open_archive_heap_regions = NULL; 1392 dump_java_heap_objects(); 1393 1394 ArchiveCompactor::relocate_well_known_klasses(); 1395 1396 char* read_only_tables_start = dump_read_only_tables(); 1397 _ro_region.pack(&_md_region); 1398 1399 char* vtbl_list = _md_region.top(); 1400 MetaspaceShared::allocate_cpp_vtable_clones(); 1401 _md_region.pack(&_od_region); 1402 1403 // Relocate the archived class file data into the od region 1404 relocate_cached_class_file(); 1405 _od_region.pack(); 1406 1407 // The 5 core spaces are allocated consecutively mc->rw->ro->md->od, so there total size 1408 // is just the spaces between the two ends. 1409 size_t core_spaces_size = _od_region.end() - _mc_region.base(); 1410 assert(core_spaces_size == (size_t)align_up(core_spaces_size, Metaspace::reserve_alignment()), 1411 "should already be aligned"); 1412 1413 // During patching, some virtual methods may be called, so at this point 1414 // the vtables must contain valid methods (as filled in by CppVtableCloner::allocate). 1415 MetaspaceShared::patch_cpp_vtable_pointers(); 1416 1417 // The vtable clones contain addresses of the current process. 1418 // We don't want to write these addresses into the archive. 1419 MetaspaceShared::zero_cpp_vtable_clones_for_writing(); 1420 1421 // Create and write the archive file that maps the shared spaces. 1422 1423 FileMapInfo* mapinfo = new FileMapInfo(); 1424 mapinfo->populate_header(os::vm_allocation_granularity()); 1425 mapinfo->set_read_only_tables_start(read_only_tables_start); 1426 mapinfo->set_misc_data_patching_start(vtbl_list); 1427 mapinfo->set_cds_i2i_entry_code_buffers(MetaspaceShared::cds_i2i_entry_code_buffers()); 1428 mapinfo->set_cds_i2i_entry_code_buffers_size(MetaspaceShared::cds_i2i_entry_code_buffers_size()); 1429 mapinfo->set_core_spaces_size(core_spaces_size); 1430 1431 for (int pass=1; pass<=2; pass++) { 1432 if (pass == 1) { 1433 // The first pass doesn't actually write the data to disk. All it 1434 // does is to update the fields in the mapinfo->_header. 1435 } else { 1436 // After the first pass, the contents of mapinfo->_header are finalized, 1437 // so we can compute the header's CRC, and write the contents of the header 1438 // and the regions into disk. 1439 mapinfo->open_for_write(); 1440 mapinfo->set_header_crc(mapinfo->compute_header_crc()); 1441 } 1442 mapinfo->write_header(); 1443 1444 // NOTE: md contains the trampoline code for method entries, which are patched at run time, 1445 // so it needs to be read/write. 1446 write_region(mapinfo, MetaspaceShared::mc, &_mc_region, /*read_only=*/false,/*allow_exec=*/true); 1447 write_region(mapinfo, MetaspaceShared::rw, &_rw_region, /*read_only=*/false,/*allow_exec=*/false); 1448 write_region(mapinfo, MetaspaceShared::ro, &_ro_region, /*read_only=*/true, /*allow_exec=*/false); 1449 write_region(mapinfo, MetaspaceShared::md, &_md_region, /*read_only=*/false,/*allow_exec=*/false); 1450 write_region(mapinfo, MetaspaceShared::od, &_od_region, /*read_only=*/true, /*allow_exec=*/false); 1451 1452 _total_string_region_size = mapinfo->write_archive_heap_regions( 1453 _closed_archive_heap_regions, 1454 MetaspaceShared::first_string, 1455 MetaspaceShared::max_strings); 1456 _total_open_archive_region_size = mapinfo->write_archive_heap_regions( 1457 _open_archive_heap_regions, 1458 MetaspaceShared::first_open_archive_heap_region, 1459 MetaspaceShared::max_open_archive_heap_region); 1460 } 1461 1462 mapinfo->close(); 1463 1464 // Restore the vtable in case we invoke any virtual methods. 1465 MetaspaceShared::clone_cpp_vtables((intptr_t*)vtbl_list); 1466 1467 print_region_stats(); 1468 1469 if (log_is_enabled(Info, cds)) { 1470 ArchiveCompactor::alloc_stats()->print_stats(int(_ro_region.used()), int(_rw_region.used()), 1471 int(_mc_region.used()), int(_md_region.used())); 1472 } 1473 1474 if (PrintSystemDictionaryAtExit) { 1475 SystemDictionary::print(); 1476 } 1477 // There may be other pending VM operations that operate on the InstanceKlasses, 1478 // which will fail because InstanceKlasses::remove_unshareable_info() 1479 // has been called. Forget these operations and exit the VM directly. 1480 vm_direct_exit(0); 1481 } 1482 1483 void VM_PopulateDumpSharedSpace::print_region_stats() { 1484 // Print statistics of all the regions 1485 const size_t total_reserved = _ro_region.reserved() + _rw_region.reserved() + 1486 _mc_region.reserved() + _md_region.reserved() + 1487 _od_region.reserved() + 1488 _total_string_region_size + 1489 _total_open_archive_region_size; 1490 const size_t total_bytes = _ro_region.used() + _rw_region.used() + 1491 _mc_region.used() + _md_region.used() + 1492 _od_region.used() + 1493 _total_string_region_size + 1494 _total_open_archive_region_size; 1495 const double total_u_perc = percent_of(total_bytes, total_reserved); 1496 1497 _mc_region.print(total_reserved); 1498 _rw_region.print(total_reserved); 1499 _ro_region.print(total_reserved); 1500 _md_region.print(total_reserved); 1501 _od_region.print(total_reserved); 1502 print_heap_region_stats(_closed_archive_heap_regions, "st", total_reserved); 1503 print_heap_region_stats(_open_archive_heap_regions, "oa", total_reserved); 1504 1505 tty->print_cr("total : " SIZE_FORMAT_W(9) " [100.0%% of total] out of " SIZE_FORMAT_W(9) " bytes [%5.1f%% used]", 1506 total_bytes, total_reserved, total_u_perc); 1507 } 1508 1509 void VM_PopulateDumpSharedSpace::print_heap_region_stats(GrowableArray<MemRegion> *heap_mem, 1510 const char *name, const size_t total_size) { 1511 int arr_len = heap_mem == NULL ? 0 : heap_mem->length(); 1512 for (int i = 0; i < arr_len; i++) { 1513 char* start = (char*)heap_mem->at(i).start(); 1514 size_t size = heap_mem->at(i).byte_size(); 1515 char* top = start + size; 1516 tty->print_cr("%s%d space: " SIZE_FORMAT_W(9) " [ %4.1f%% of total] out of " SIZE_FORMAT_W(9) " bytes [100.0%% used] at " INTPTR_FORMAT, 1517 name, i, size, size/double(total_size)*100.0, size, p2i(start)); 1518 1519 } 1520 } 1521 1522 // Update a Java object to point its Klass* to the new location after 1523 // shared archive has been compacted. 1524 void MetaspaceShared::relocate_klass_ptr(oop o) { 1525 assert(DumpSharedSpaces, "sanity"); 1526 Klass* k = ArchiveCompactor::get_relocated_klass(o->klass()); 1527 o->set_klass(k); 1528 } 1529 1530 Klass* MetaspaceShared::get_relocated_klass(Klass *k) { 1531 assert(DumpSharedSpaces, "sanity"); 1532 return ArchiveCompactor::get_relocated_klass(k); 1533 } 1534 1535 class LinkSharedClassesClosure : public KlassClosure { 1536 Thread* THREAD; 1537 bool _made_progress; 1538 public: 1539 LinkSharedClassesClosure(Thread* thread) : THREAD(thread), _made_progress(false) {} 1540 1541 void reset() { _made_progress = false; } 1542 bool made_progress() const { return _made_progress; } 1543 1544 void do_klass(Klass* k) { 1545 if (k->is_instance_klass()) { 1546 InstanceKlass* ik = InstanceKlass::cast(k); 1547 // Link the class to cause the bytecodes to be rewritten and the 1548 // cpcache to be created. Class verification is done according 1549 // to -Xverify setting. 1550 _made_progress |= MetaspaceShared::try_link_class(ik, THREAD); 1551 guarantee(!HAS_PENDING_EXCEPTION, "exception in link_class"); 1552 1553 ik->constants()->resolve_class_constants(THREAD); 1554 } 1555 } 1556 }; 1557 1558 class CheckSharedClassesClosure : public KlassClosure { 1559 bool _made_progress; 1560 public: 1561 CheckSharedClassesClosure() : _made_progress(false) {} 1562 1563 void reset() { _made_progress = false; } 1564 bool made_progress() const { return _made_progress; } 1565 void do_klass(Klass* k) { 1566 if (k->is_instance_klass() && InstanceKlass::cast(k)->check_sharing_error_state()) { 1567 _made_progress = true; 1568 } 1569 } 1570 }; 1571 1572 void MetaspaceShared::check_shared_class_loader_type(Klass* k) { 1573 if (k->is_instance_klass()) { 1574 InstanceKlass* ik = InstanceKlass::cast(k); 1575 u2 loader_type = ik->loader_type(); 1576 ResourceMark rm; 1577 guarantee(loader_type != 0, 1578 "Class loader type is not set for this class %s", ik->name()->as_C_string()); 1579 } 1580 } 1581 1582 void MetaspaceShared::link_and_cleanup_shared_classes(TRAPS) { 1583 // We need to iterate because verification may cause additional classes 1584 // to be loaded. 1585 LinkSharedClassesClosure link_closure(THREAD); 1586 do { 1587 link_closure.reset(); 1588 ClassLoaderDataGraph::loaded_classes_do(&link_closure); 1589 guarantee(!HAS_PENDING_EXCEPTION, "exception in link_class"); 1590 } while (link_closure.made_progress()); 1591 1592 if (_has_error_classes) { 1593 // Mark all classes whose super class or interfaces failed verification. 1594 CheckSharedClassesClosure check_closure; 1595 do { 1596 // Not completely sure if we need to do this iteratively. Anyway, 1597 // we should come here only if there are unverifiable classes, which 1598 // shouldn't happen in normal cases. So better safe than sorry. 1599 check_closure.reset(); 1600 ClassLoaderDataGraph::loaded_classes_do(&check_closure); 1601 } while (check_closure.made_progress()); 1602 1603 if (IgnoreUnverifiableClassesDuringDump) { 1604 // This is useful when running JCK or SQE tests. You should not 1605 // enable this when running real apps. 1606 SystemDictionary::remove_classes_in_error_state(); 1607 } else { 1608 tty->print_cr("Please remove the unverifiable classes from your class list and try again"); 1609 exit(1); 1610 } 1611 } 1612 } 1613 1614 void MetaspaceShared::prepare_for_dumping() { 1615 Arguments::check_unsupported_dumping_properties(); 1616 ClassLoader::initialize_shared_path(); 1617 FileMapInfo::allocate_classpath_entry_table(); 1618 } 1619 1620 // Preload classes from a list, populate the shared spaces and dump to a 1621 // file. 1622 void MetaspaceShared::preload_and_dump(TRAPS) { 1623 { TraceTime timer("Dump Shared Spaces", TRACETIME_LOG(Info, startuptime)); 1624 ResourceMark rm; 1625 char class_list_path_str[JVM_MAXPATHLEN]; 1626 // Preload classes to be shared. 1627 // Should use some os:: method rather than fopen() here. aB. 1628 const char* class_list_path; 1629 if (SharedClassListFile == NULL) { 1630 // Construct the path to the class list (in jre/lib) 1631 // Walk up two directories from the location of the VM and 1632 // optionally tack on "lib" (depending on platform) 1633 os::jvm_path(class_list_path_str, sizeof(class_list_path_str)); 1634 for (int i = 0; i < 3; i++) { 1635 char *end = strrchr(class_list_path_str, *os::file_separator()); 1636 if (end != NULL) *end = '\0'; 1637 } 1638 int class_list_path_len = (int)strlen(class_list_path_str); 1639 if (class_list_path_len >= 3) { 1640 if (strcmp(class_list_path_str + class_list_path_len - 3, "lib") != 0) { 1641 if (class_list_path_len < JVM_MAXPATHLEN - 4) { 1642 jio_snprintf(class_list_path_str + class_list_path_len, 1643 sizeof(class_list_path_str) - class_list_path_len, 1644 "%slib", os::file_separator()); 1645 class_list_path_len += 4; 1646 } 1647 } 1648 } 1649 if (class_list_path_len < JVM_MAXPATHLEN - 10) { 1650 jio_snprintf(class_list_path_str + class_list_path_len, 1651 sizeof(class_list_path_str) - class_list_path_len, 1652 "%sclasslist", os::file_separator()); 1653 } 1654 class_list_path = class_list_path_str; 1655 } else { 1656 class_list_path = SharedClassListFile; 1657 } 1658 1659 tty->print_cr("Loading classes to share ..."); 1660 _has_error_classes = false; 1661 int class_count = preload_classes(class_list_path, THREAD); 1662 if (ExtraSharedClassListFile) { 1663 class_count += preload_classes(ExtraSharedClassListFile, THREAD); 1664 } 1665 tty->print_cr("Loading classes to share: done."); 1666 1667 log_info(cds)("Shared spaces: preloaded %d classes", class_count); 1668 1669 // Rewrite and link classes 1670 tty->print_cr("Rewriting and linking classes ..."); 1671 1672 // Link any classes which got missed. This would happen if we have loaded classes that 1673 // were not explicitly specified in the classlist. E.g., if an interface implemented by class K 1674 // fails verification, all other interfaces that were not specified in the classlist but 1675 // are implemented by K are not verified. 1676 link_and_cleanup_shared_classes(CATCH); 1677 tty->print_cr("Rewriting and linking classes: done"); 1678 1679 SystemDictionary::clear_invoke_method_table(); 1680 1681 VM_PopulateDumpSharedSpace op; 1682 VMThread::execute(&op); 1683 } 1684 } 1685 1686 1687 int MetaspaceShared::preload_classes(const char* class_list_path, TRAPS) { 1688 ClassListParser parser(class_list_path); 1689 int class_count = 0; 1690 1691 while (parser.parse_one_line()) { 1692 Klass* klass = ClassLoaderExt::load_one_class(&parser, THREAD); 1693 if (HAS_PENDING_EXCEPTION) { 1694 if (klass == NULL && 1695 (PENDING_EXCEPTION->klass()->name() == vmSymbols::java_lang_ClassNotFoundException())) { 1696 // print a warning only when the pending exception is class not found 1697 tty->print_cr("Preload Warning: Cannot find %s", parser.current_class_name()); 1698 } 1699 CLEAR_PENDING_EXCEPTION; 1700 } 1701 if (klass != NULL) { 1702 if (log_is_enabled(Trace, cds)) { 1703 ResourceMark rm; 1704 log_trace(cds)("Shared spaces preloaded: %s", klass->external_name()); 1705 } 1706 1707 if (klass->is_instance_klass()) { 1708 InstanceKlass* ik = InstanceKlass::cast(klass); 1709 1710 // Link the class to cause the bytecodes to be rewritten and the 1711 // cpcache to be created. The linking is done as soon as classes 1712 // are loaded in order that the related data structures (klass and 1713 // cpCache) are located together. 1714 try_link_class(ik, THREAD); 1715 guarantee(!HAS_PENDING_EXCEPTION, "exception in link_class"); 1716 } 1717 1718 class_count++; 1719 } 1720 } 1721 1722 return class_count; 1723 } 1724 1725 // Returns true if the class's status has changed 1726 bool MetaspaceShared::try_link_class(InstanceKlass* ik, TRAPS) { 1727 assert(DumpSharedSpaces, "should only be called during dumping"); 1728 if (ik->init_state() < InstanceKlass::linked) { 1729 bool saved = BytecodeVerificationLocal; 1730 if (!(ik->is_shared_boot_class())) { 1731 // The verification decision is based on BytecodeVerificationRemote 1732 // for non-system classes. Since we are using the NULL classloader 1733 // to load non-system classes during dumping, we need to temporarily 1734 // change BytecodeVerificationLocal to be the same as 1735 // BytecodeVerificationRemote. Note this can cause the parent system 1736 // classes also being verified. The extra overhead is acceptable during 1737 // dumping. 1738 BytecodeVerificationLocal = BytecodeVerificationRemote; 1739 } 1740 ik->link_class(THREAD); 1741 if (HAS_PENDING_EXCEPTION) { 1742 ResourceMark rm; 1743 tty->print_cr("Preload Warning: Verification failed for %s", 1744 ik->external_name()); 1745 CLEAR_PENDING_EXCEPTION; 1746 ik->set_in_error_state(); 1747 _has_error_classes = true; 1748 } 1749 BytecodeVerificationLocal = saved; 1750 return true; 1751 } else { 1752 return false; 1753 } 1754 } 1755 1756 #if INCLUDE_CDS_JAVA_HEAP 1757 void VM_PopulateDumpSharedSpace::dump_java_heap_objects() { 1758 if (!MetaspaceShared::is_heap_object_archiving_allowed()) { 1759 if (log_is_enabled(Info, cds)) { 1760 log_info(cds)( 1761 "Archived java heap is not supported as UseG1GC, " 1762 "UseCompressedOops and UseCompressedClassPointers are required." 1763 "Current settings: UseG1GC=%s, UseCompressedOops=%s, UseCompressedClassPointers=%s.", 1764 BOOL_TO_STR(UseG1GC), BOOL_TO_STR(UseCompressedOops), 1765 BOOL_TO_STR(UseCompressedClassPointers)); 1766 } 1767 return; 1768 } 1769 1770 { 1771 NoSafepointVerifier nsv; 1772 1773 // Cache for recording where the archived objects are copied to 1774 MetaspaceShared::create_archive_object_cache(); 1775 1776 tty->print_cr("Dumping objects to closed archive heap region ..."); 1777 NOT_PRODUCT(StringTable::verify()); 1778 // The closed space has maximum two regions. See FileMapInfo::write_archive_heap_regions() for details. 1779 _closed_archive_heap_regions = new GrowableArray<MemRegion>(2); 1780 MetaspaceShared::dump_closed_archive_heap_objects(_closed_archive_heap_regions); 1781 1782 tty->print_cr("Dumping objects to open archive heap region ..."); 1783 _open_archive_heap_regions = new GrowableArray<MemRegion>(2); 1784 MetaspaceShared::dump_open_archive_heap_objects(_open_archive_heap_regions); 1785 1786 MetaspaceShared::destroy_archive_object_cache(); 1787 } 1788 1789 G1HeapVerifier::verify_archive_regions(); 1790 } 1791 1792 void MetaspaceShared::dump_closed_archive_heap_objects( 1793 GrowableArray<MemRegion> * closed_archive) { 1794 assert(is_heap_object_archiving_allowed(), "Cannot dump java heap objects"); 1795 1796 Thread* THREAD = Thread::current(); 1797 G1CollectedHeap::heap()->begin_archive_alloc_range(); 1798 1799 // Archive interned string objects 1800 StringTable::write_to_archive(closed_archive); 1801 1802 G1CollectedHeap::heap()->end_archive_alloc_range(closed_archive, 1803 os::vm_allocation_granularity()); 1804 } 1805 1806 void MetaspaceShared::dump_open_archive_heap_objects( 1807 GrowableArray<MemRegion> * open_archive) { 1808 assert(UseG1GC, "Only support G1 GC"); 1809 assert(UseCompressedOops && UseCompressedClassPointers, 1810 "Only support UseCompressedOops and UseCompressedClassPointers enabled"); 1811 1812 Thread* THREAD = Thread::current(); 1813 G1CollectedHeap::heap()->begin_archive_alloc_range(true /* open */); 1814 1815 java_lang_Class::archive_basic_type_mirrors(THREAD); 1816 1817 MetaspaceShared::archive_klass_objects(THREAD); 1818 1819 G1CollectedHeap::heap()->end_archive_alloc_range(open_archive, 1820 os::vm_allocation_granularity()); 1821 } 1822 1823 MetaspaceShared::ArchivedObjectCache* MetaspaceShared::_archive_object_cache = NULL; 1824 oop MetaspaceShared::find_archived_heap_object(oop obj) { 1825 assert(DumpSharedSpaces, "dump-time only"); 1826 ArchivedObjectCache* cache = MetaspaceShared::archive_object_cache(); 1827 oop* p = cache->get(obj); 1828 if (p != NULL) { 1829 return *p; 1830 } else { 1831 return NULL; 1832 } 1833 } 1834 1835 oop MetaspaceShared::archive_heap_object(oop obj, Thread* THREAD) { 1836 assert(DumpSharedSpaces, "dump-time only"); 1837 1838 oop ao = find_archived_heap_object(obj); 1839 if (ao != NULL) { 1840 // already archived 1841 return ao; 1842 } 1843 1844 int len = obj->size(); 1845 if (G1CollectedHeap::heap()->is_archive_alloc_too_large(len)) { 1846 return NULL; 1847 } 1848 1849 int hash = obj->identity_hash(); 1850 oop archived_oop = (oop)G1CollectedHeap::heap()->archive_mem_allocate(len); 1851 if (archived_oop != NULL) { 1852 Copy::aligned_disjoint_words((HeapWord*)obj, (HeapWord*)archived_oop, len); 1853 relocate_klass_ptr(archived_oop); 1854 ArchivedObjectCache* cache = MetaspaceShared::archive_object_cache(); 1855 cache->put(obj, archived_oop); 1856 } 1857 log_debug(cds)("Archived heap object " PTR_FORMAT " ==> " PTR_FORMAT, 1858 p2i(obj), p2i(archived_oop)); 1859 return archived_oop; 1860 } 1861 1862 void MetaspaceShared::archive_klass_objects(Thread* THREAD) { 1863 int i; 1864 for (i = 0; i < _global_klass_objects->length(); i++) { 1865 Klass* k = _global_klass_objects->at(i); 1866 1867 // archive mirror object 1868 java_lang_Class::archive_mirror(k, CHECK); 1869 1870 // archive the resolved_referenes array 1871 if (k->is_instance_klass()) { 1872 InstanceKlass* ik = InstanceKlass::cast(k); 1873 ik->constants()->archive_resolved_references(THREAD); 1874 } 1875 } 1876 } 1877 1878 void MetaspaceShared::fixup_mapped_heap_regions() { 1879 FileMapInfo *mapinfo = FileMapInfo::current_info(); 1880 mapinfo->fixup_mapped_heap_regions(); 1881 } 1882 #endif // INCLUDE_CDS_JAVA_HEAP 1883 1884 // Closure for serializing initialization data in from a data area 1885 // (ptr_array) read from the shared file. 1886 1887 class ReadClosure : public SerializeClosure { 1888 private: 1889 intptr_t** _ptr_array; 1890 1891 inline intptr_t nextPtr() { 1892 return *(*_ptr_array)++; 1893 } 1894 1895 public: 1896 ReadClosure(intptr_t** ptr_array) { _ptr_array = ptr_array; } 1897 1898 void do_ptr(void** p) { 1899 assert(*p == NULL, "initializing previous initialized pointer."); 1900 intptr_t obj = nextPtr(); 1901 assert((intptr_t)obj >= 0 || (intptr_t)obj < -100, 1902 "hit tag while initializing ptrs."); 1903 *p = (void*)obj; 1904 } 1905 1906 void do_u4(u4* p) { 1907 intptr_t obj = nextPtr(); 1908 *p = (u4)(uintx(obj)); 1909 } 1910 1911 void do_tag(int tag) { 1912 int old_tag; 1913 old_tag = (int)(intptr_t)nextPtr(); 1914 // do_int(&old_tag); 1915 assert(tag == old_tag, "old tag doesn't match"); 1916 FileMapInfo::assert_mark(tag == old_tag); 1917 } 1918 1919 void do_oop(oop *p) { 1920 narrowOop o = (narrowOop)nextPtr(); 1921 if (o == 0 || !MetaspaceShared::open_archive_heap_region_mapped()) { 1922 p = NULL; 1923 } else { 1924 assert(MetaspaceShared::is_heap_object_archiving_allowed(), 1925 "Archived heap object is not allowed"); 1926 assert(MetaspaceShared::open_archive_heap_region_mapped(), 1927 "Open archive heap region is not mapped"); 1928 RootAccess<IN_ARCHIVE_ROOT>::oop_store(p, oopDesc::decode_heap_oop_not_null(o)); 1929 } 1930 } 1931 1932 void do_region(u_char* start, size_t size) { 1933 assert((intptr_t)start % sizeof(intptr_t) == 0, "bad alignment"); 1934 assert(size % sizeof(intptr_t) == 0, "bad size"); 1935 do_tag((int)size); 1936 while (size > 0) { 1937 *(intptr_t*)start = nextPtr(); 1938 start += sizeof(intptr_t); 1939 size -= sizeof(intptr_t); 1940 } 1941 } 1942 1943 bool reading() const { return true; } 1944 }; 1945 1946 // Return true if given address is in the misc data region 1947 bool MetaspaceShared::is_in_shared_region(const void* p, int idx) { 1948 return UseSharedSpaces && FileMapInfo::current_info()->is_in_shared_region(p, idx); 1949 } 1950 1951 bool MetaspaceShared::is_in_trampoline_frame(address addr) { 1952 if (UseSharedSpaces && is_in_shared_region(addr, MetaspaceShared::mc)) { 1953 return true; 1954 } 1955 return false; 1956 } 1957 1958 void MetaspaceShared::print_shared_spaces() { 1959 if (UseSharedSpaces) { 1960 FileMapInfo::current_info()->print_shared_spaces(); 1961 } 1962 } 1963 1964 1965 // Map shared spaces at requested addresses and return if succeeded. 1966 bool MetaspaceShared::map_shared_spaces(FileMapInfo* mapinfo) { 1967 size_t image_alignment = mapinfo->alignment(); 1968 1969 #ifndef _WINDOWS 1970 // Map in the shared memory and then map the regions on top of it. 1971 // On Windows, don't map the memory here because it will cause the 1972 // mappings of the regions to fail. 1973 ReservedSpace shared_rs = mapinfo->reserve_shared_memory(); 1974 if (!shared_rs.is_reserved()) return false; 1975 #endif 1976 1977 assert(!DumpSharedSpaces, "Should not be called with DumpSharedSpaces"); 1978 1979 char* ro_base = NULL; char* ro_top; 1980 char* rw_base = NULL; char* rw_top; 1981 char* mc_base = NULL; char* mc_top; 1982 char* md_base = NULL; char* md_top; 1983 char* od_base = NULL; char* od_top; 1984 1985 // Map each shared region 1986 if ((mc_base = mapinfo->map_region(mc, &mc_top)) != NULL && 1987 (rw_base = mapinfo->map_region(rw, &rw_top)) != NULL && 1988 (ro_base = mapinfo->map_region(ro, &ro_top)) != NULL && 1989 (md_base = mapinfo->map_region(md, &md_top)) != NULL && 1990 (od_base = mapinfo->map_region(od, &od_top)) != NULL && 1991 (image_alignment == (size_t)os::vm_allocation_granularity()) && 1992 mapinfo->validate_classpath_entry_table()) { 1993 // Success -- set up MetaspaceObj::_shared_metaspace_{base,top} for 1994 // fast checking in MetaspaceShared::is_in_shared_metaspace() and 1995 // MetaspaceObj::is_shared(). 1996 // 1997 // We require that mc->rw->ro->md->od to be laid out consecutively, with no 1998 // gaps between them. That way, we can ensure that the OS won't be able to 1999 // allocate any new memory spaces inside _shared_metaspace_{base,top}, which 2000 // would mess up the simple comparision in MetaspaceShared::is_in_shared_metaspace(). 2001 assert(mc_base < ro_base && mc_base < rw_base && mc_base < md_base && mc_base < od_base, "must be"); 2002 assert(od_top > ro_top && od_top > rw_top && od_top > md_top && od_top > mc_top , "must be"); 2003 assert(mc_top == rw_base, "must be"); 2004 assert(rw_top == ro_base, "must be"); 2005 assert(ro_top == md_base, "must be"); 2006 assert(md_top == od_base, "must be"); 2007 2008 MetaspaceObj::_shared_metaspace_base = (void*)mc_base; 2009 MetaspaceObj::_shared_metaspace_top = (void*)od_top; 2010 return true; 2011 } else { 2012 // If there was a failure in mapping any of the spaces, unmap the ones 2013 // that succeeded 2014 if (ro_base != NULL) mapinfo->unmap_region(ro); 2015 if (rw_base != NULL) mapinfo->unmap_region(rw); 2016 if (mc_base != NULL) mapinfo->unmap_region(mc); 2017 if (md_base != NULL) mapinfo->unmap_region(md); 2018 if (od_base != NULL) mapinfo->unmap_region(od); 2019 #ifndef _WINDOWS 2020 // Release the entire mapped region 2021 shared_rs.release(); 2022 #endif 2023 // If -Xshare:on is specified, print out the error message and exit VM, 2024 // otherwise, set UseSharedSpaces to false and continue. 2025 if (RequireSharedSpaces || PrintSharedArchiveAndExit) { 2026 vm_exit_during_initialization("Unable to use shared archive.", "Failed map_region for using -Xshare:on."); 2027 } else { 2028 FLAG_SET_DEFAULT(UseSharedSpaces, false); 2029 } 2030 return false; 2031 } 2032 } 2033 2034 // Read the miscellaneous data from the shared file, and 2035 // serialize it out to its various destinations. 2036 2037 void MetaspaceShared::initialize_shared_spaces() { 2038 FileMapInfo *mapinfo = FileMapInfo::current_info(); 2039 _cds_i2i_entry_code_buffers = mapinfo->cds_i2i_entry_code_buffers(); 2040 _cds_i2i_entry_code_buffers_size = mapinfo->cds_i2i_entry_code_buffers_size(); 2041 _core_spaces_size = mapinfo->core_spaces_size(); 2042 char* buffer = mapinfo->misc_data_patching_start(); 2043 clone_cpp_vtables((intptr_t*)buffer); 2044 2045 // The rest of the data is now stored in the RW region 2046 buffer = mapinfo->read_only_tables_start(); 2047 int sharedDictionaryLen = *(intptr_t*)buffer; 2048 buffer += sizeof(intptr_t); 2049 int number_of_entries = *(intptr_t*)buffer; 2050 buffer += sizeof(intptr_t); 2051 SystemDictionary::set_shared_dictionary((HashtableBucket<mtClass>*)buffer, 2052 sharedDictionaryLen, 2053 number_of_entries); 2054 buffer += sharedDictionaryLen; 2055 2056 // The following data are the linked list elements 2057 // (HashtableEntry objects) for the shared dictionary table. 2058 2059 int len = *(intptr_t*)buffer; // skip over shared dictionary entries 2060 buffer += sizeof(intptr_t); 2061 buffer += len; 2062 2063 // Verify various attributes of the archive, plus initialize the 2064 // shared string/symbol tables 2065 intptr_t* array = (intptr_t*)buffer; 2066 ReadClosure rc(&array); 2067 serialize(&rc); 2068 2069 // Initialize the run-time symbol table. 2070 SymbolTable::create_table(); 2071 2072 // Close the mapinfo file 2073 mapinfo->close(); 2074 2075 if (PrintSharedArchiveAndExit) { 2076 if (PrintSharedDictionary) { 2077 tty->print_cr("\nShared classes:\n"); 2078 SystemDictionary::print_shared(tty); 2079 } 2080 if (_archive_loading_failed) { 2081 tty->print_cr("archive is invalid"); 2082 vm_exit(1); 2083 } else { 2084 tty->print_cr("archive is valid"); 2085 vm_exit(0); 2086 } 2087 } 2088 } 2089 2090 // JVM/TI RedefineClasses() support: 2091 bool MetaspaceShared::remap_shared_readonly_as_readwrite() { 2092 assert(SafepointSynchronize::is_at_safepoint(), "must be at safepoint"); 2093 2094 if (UseSharedSpaces) { 2095 // remap the shared readonly space to shared readwrite, private 2096 FileMapInfo* mapinfo = FileMapInfo::current_info(); 2097 if (!mapinfo->remap_shared_readonly_as_readwrite()) { 2098 return false; 2099 } 2100 _remapped_readwrite = true; 2101 } 2102 return true; 2103 } 2104 2105 void MetaspaceShared::report_out_of_space(const char* name, size_t needed_bytes) { 2106 // This is highly unlikely to happen on 64-bits because we have reserved a 4GB space. 2107 // On 32-bit we reserve only 256MB so you could run out of space with 100,000 classes 2108 // or so. 2109 _mc_region.print_out_of_space_msg(name, needed_bytes); 2110 _rw_region.print_out_of_space_msg(name, needed_bytes); 2111 _ro_region.print_out_of_space_msg(name, needed_bytes); 2112 _md_region.print_out_of_space_msg(name, needed_bytes); 2113 _od_region.print_out_of_space_msg(name, needed_bytes); 2114 2115 vm_exit_during_initialization(err_msg("Unable to allocate from '%s' region", name), 2116 "Please reduce the number of shared classes."); 2117 }