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 #include "gc/g1/g1SATBCardTableModRefBS.hpp" 42 #endif 43 #include "gc/shared/gcLocker.hpp" 44 #include "interpreter/bytecodeStream.hpp" 45 #include "interpreter/bytecodes.hpp" 46 #include "logging/log.hpp" 47 #include "logging/logMessage.hpp" 48 #include "memory/filemap.hpp" 49 #include "memory/metaspace.hpp" 50 #include "memory/metaspaceShared.hpp" 51 #include "memory/resourceArea.hpp" 52 #include "oops/instanceClassLoaderKlass.hpp" 53 #include "oops/instanceMirrorKlass.hpp" 54 #include "oops/instanceRefKlass.hpp" 55 #include "oops/objArrayKlass.hpp" 56 #include "oops/objArrayOop.hpp" 57 #include "oops/oop.inline.hpp" 58 #include "oops/typeArrayKlass.hpp" 59 #include "prims/jvmtiRedefineClasses.hpp" 60 #include "runtime/timerTrace.hpp" 61 #include "runtime/os.hpp" 62 #include "runtime/signature.hpp" 63 #include "runtime/vmThread.hpp" 64 #include "runtime/vm_operations.hpp" 65 #include "utilities/align.hpp" 66 #include "utilities/defaultStream.hpp" 67 #include "utilities/hashtable.inline.hpp" 68 #include "memory/metaspaceClosure.hpp" 69 70 ReservedSpace MetaspaceShared::_shared_rs; 71 VirtualSpace MetaspaceShared::_shared_vs; 72 MetaspaceSharedStats MetaspaceShared::_stats; 73 bool MetaspaceShared::_has_error_classes; 74 bool MetaspaceShared::_archive_loading_failed = false; 75 bool MetaspaceShared::_remapped_readwrite = false; 76 bool MetaspaceShared::_open_archive_heap_region_mapped = false; 77 address MetaspaceShared::_cds_i2i_entry_code_buffers = NULL; 78 size_t MetaspaceShared::_cds_i2i_entry_code_buffers_size = 0; 79 size_t MetaspaceShared::_core_spaces_size = 0; 80 81 // The CDS archive is divided into the following regions: 82 // mc - misc code (the method entry trampolines) 83 // rw - read-write metadata 84 // ro - read-only metadata and read-only tables 85 // md - misc data (the c++ vtables) 86 // od - optional data (original class files) 87 // 88 // s0 - shared strings(closed archive heap space) #0 89 // s1 - shared strings(closed archive heap space) #1 (may be empty) 90 // oa0 - open archive heap space #0 91 // oa1 - open archive heap space #1 (may be empty) 92 // 93 // The mc, rw, ro, md and od regions are linearly allocated, starting from 94 // SharedBaseAddress, in the order of mc->rw->ro->md->od. The size of these 5 regions 95 // are page-aligned, and there's no gap between any consecutive regions. 96 // 97 // These 5 regions are populated in the following steps: 98 // [1] All classes are loaded in MetaspaceShared::preload_classes(). All metadata are 99 // temporarily allocated outside of the shared regions. Only the method entry 100 // trampolines are written into the mc region. 101 // [2] ArchiveCompactor copies RW metadata into the rw region. 102 // [3] ArchiveCompactor copies RO metadata into the ro region. 103 // [4] SymbolTable, StringTable, SystemDictionary, and a few other read-only data 104 // are copied into the ro region as read-only tables. 105 // [5] C++ vtables are copied into the md region. 106 // [6] Original class files are copied into the od region. 107 // 108 // The s0/s1 and oa0/oa1 regions are populated inside MetaspaceShared::dump_java_heap_objects. 109 // Their layout is independent of the other 5 regions. 110 111 class DumpRegion { 112 private: 113 const char* _name; 114 char* _base; 115 char* _top; 116 char* _end; 117 bool _is_packed; 118 119 char* expand_top_to(char* newtop) { 120 assert(is_allocatable(), "must be initialized and not packed"); 121 assert(newtop >= _top, "must not grow backwards"); 122 if (newtop > _end) { 123 MetaspaceShared::report_out_of_space(_name, newtop - _top); 124 ShouldNotReachHere(); 125 } 126 MetaspaceShared::commit_shared_space_to(newtop); 127 _top = newtop; 128 return _top; 129 } 130 131 public: 132 DumpRegion(const char* name) : _name(name), _base(NULL), _top(NULL), _end(NULL), _is_packed(false) {} 133 134 char* allocate(size_t num_bytes, size_t alignment=BytesPerWord) { 135 char* p = (char*)align_up(_top, alignment); 136 char* newtop = p + align_up(num_bytes, alignment); 137 expand_top_to(newtop); 138 memset(p, 0, newtop - p); 139 return p; 140 } 141 142 void append_intptr_t(intptr_t n) { 143 assert(is_aligned(_top, sizeof(intptr_t)), "bad alignment"); 144 intptr_t *p = (intptr_t*)_top; 145 char* newtop = _top + sizeof(intptr_t); 146 expand_top_to(newtop); 147 *p = n; 148 } 149 150 char* base() const { return _base; } 151 char* top() const { return _top; } 152 char* end() const { return _end; } 153 size_t reserved() const { return _end - _base; } 154 size_t used() const { return _top - _base; } 155 bool is_packed() const { return _is_packed; } 156 bool is_allocatable() const { 157 return !is_packed() && _base != NULL; 158 } 159 160 void print(size_t total_bytes) const { 161 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, 162 _name, used(), percent_of(used(), total_bytes), reserved(), percent_of(used(), reserved()), p2i(_base)); 163 } 164 void print_out_of_space_msg(const char* failing_region, size_t needed_bytes) { 165 tty->print("[%-8s] " PTR_FORMAT " - " PTR_FORMAT " capacity =%9d, allocated =%9d", 166 _name, p2i(_base), p2i(_top), int(_end - _base), int(_top - _base)); 167 if (strcmp(_name, failing_region) == 0) { 168 tty->print_cr(" required = %d", int(needed_bytes)); 169 } else { 170 tty->cr(); 171 } 172 } 173 174 void init(const ReservedSpace* rs) { 175 _base = _top = rs->base(); 176 _end = rs->end(); 177 } 178 void init(char* b, char* t, char* e) { 179 _base = b; 180 _top = t; 181 _end = e; 182 } 183 184 void pack(DumpRegion* next = NULL) { 185 assert(!is_packed(), "sanity"); 186 _end = (char*)align_up(_top, Metaspace::reserve_alignment()); 187 _is_packed = true; 188 if (next != NULL) { 189 next->_base = next->_top = this->_end; 190 next->_end = MetaspaceShared::shared_rs()->end(); 191 } 192 } 193 bool contains(char* p) { 194 return base() <= p && p < top(); 195 } 196 }; 197 198 199 DumpRegion _mc_region("mc"), _ro_region("ro"), _rw_region("rw"), _md_region("md"), _od_region("od"); 200 size_t _total_string_region_size = 0, _total_open_archive_region_size = 0; 201 202 char* MetaspaceShared::misc_code_space_alloc(size_t num_bytes) { 203 return _mc_region.allocate(num_bytes); 204 } 205 206 char* MetaspaceShared::read_only_space_alloc(size_t num_bytes) { 207 return _ro_region.allocate(num_bytes); 208 } 209 210 void MetaspaceShared::initialize_runtime_shared_and_meta_spaces() { 211 assert(UseSharedSpaces, "Must be called when UseSharedSpaces is enabled"); 212 213 // If using shared space, open the file that contains the shared space 214 // and map in the memory before initializing the rest of metaspace (so 215 // the addresses don't conflict) 216 address cds_address = NULL; 217 FileMapInfo* mapinfo = new FileMapInfo(); 218 219 // Open the shared archive file, read and validate the header. If 220 // initialization fails, shared spaces [UseSharedSpaces] are 221 // disabled and the file is closed. 222 // Map in spaces now also 223 if (mapinfo->initialize() && map_shared_spaces(mapinfo)) { 224 size_t cds_total = core_spaces_size(); 225 cds_address = (address)mapinfo->header()->region_addr(0); 226 #ifdef _LP64 227 if (Metaspace::using_class_space()) { 228 char* cds_end = (char*)(cds_address + cds_total); 229 cds_end = (char *)align_up(cds_end, Metaspace::reserve_alignment()); 230 // If UseCompressedClassPointers is set then allocate the metaspace area 231 // above the heap and above the CDS area (if it exists). 232 Metaspace::allocate_metaspace_compressed_klass_ptrs(cds_end, cds_address); 233 // map_heap_regions() compares the current narrow oop and klass encodings 234 // with the archived ones, so it must be done after all encodings are determined. 235 mapinfo->map_heap_regions(); 236 } 237 #endif // _LP64 238 } else { 239 assert(!mapinfo->is_open() && !UseSharedSpaces, 240 "archive file not closed or shared spaces not disabled."); 241 } 242 } 243 244 void MetaspaceShared::initialize_dumptime_shared_and_meta_spaces() { 245 assert(DumpSharedSpaces, "should be called for dump time only"); 246 const size_t reserve_alignment = Metaspace::reserve_alignment(); 247 bool large_pages = false; // No large pages when dumping the CDS archive. 248 char* shared_base = (char*)align_up((char*)SharedBaseAddress, reserve_alignment); 249 250 #ifdef _LP64 251 // On 64-bit VM, the heap and class space layout will be the same as if 252 // you're running in -Xshare:on mode: 253 // 254 // +-- SharedBaseAddress (default = 0x800000000) 255 // v 256 // +-..---------+---------+ ... +----+----+----+----+----+---------------+ 257 // | Heap | Archive | | MC | RW | RO | MD | OD | class space | 258 // +-..---------+---------+ ... +----+----+----+----+----+---------------+ 259 // |<-- MaxHeapSize -->| |<-- UnscaledClassSpaceMax = 4GB ------->| 260 // 261 const uint64_t UnscaledClassSpaceMax = (uint64_t(max_juint) + 1); 262 const size_t cds_total = align_down(UnscaledClassSpaceMax, reserve_alignment); 263 #else 264 // We don't support archives larger than 256MB on 32-bit due to limited virtual address space. 265 size_t cds_total = align_down(256*M, reserve_alignment); 266 #endif 267 268 // First try to reserve the space at the specified SharedBaseAddress. 269 _shared_rs = ReservedSpace(cds_total, reserve_alignment, large_pages, shared_base); 270 if (_shared_rs.is_reserved()) { 271 assert(shared_base == 0 || _shared_rs.base() == shared_base, "should match"); 272 } else { 273 // Get a mmap region anywhere if the SharedBaseAddress fails. 274 _shared_rs = ReservedSpace(cds_total, reserve_alignment, large_pages); 275 } 276 if (!_shared_rs.is_reserved()) { 277 vm_exit_during_initialization("Unable to reserve memory for shared space", 278 err_msg(SIZE_FORMAT " bytes.", cds_total)); 279 } 280 281 #ifdef _LP64 282 // During dump time, we allocate 4GB (UnscaledClassSpaceMax) of space and split it up: 283 // + The upper 1 GB is used as the "temporary compressed class space" -- preload_classes() 284 // will store Klasses into this space. 285 // + The lower 3 GB is used for the archive -- when preload_classes() is done, 286 // ArchiveCompactor will copy the class metadata into this space, first the RW parts, 287 // then the RO parts. 288 289 assert(UseCompressedOops && UseCompressedClassPointers, 290 "UseCompressedOops and UseCompressedClassPointers must be set"); 291 292 size_t max_archive_size = align_down(cds_total * 3 / 4, reserve_alignment); 293 ReservedSpace tmp_class_space = _shared_rs.last_part(max_archive_size); 294 CompressedClassSpaceSize = align_down(tmp_class_space.size(), reserve_alignment); 295 _shared_rs = _shared_rs.first_part(max_archive_size); 296 297 // Set up compress class pointers. 298 Universe::set_narrow_klass_base((address)_shared_rs.base()); 299 // Set narrow_klass_shift to be LogKlassAlignmentInBytes. This is consistent 300 // with AOT. 301 Universe::set_narrow_klass_shift(LogKlassAlignmentInBytes); 302 303 Metaspace::initialize_class_space(tmp_class_space); 304 tty->print_cr("narrow_klass_base = " PTR_FORMAT ", narrow_klass_shift = %d", 305 p2i(Universe::narrow_klass_base()), Universe::narrow_klass_shift()); 306 307 tty->print_cr("Allocated temporary class space: " SIZE_FORMAT " bytes at " PTR_FORMAT, 308 CompressedClassSpaceSize, p2i(tmp_class_space.base())); 309 #endif 310 311 // Start with 0 committed bytes. The memory will be committed as needed by 312 // MetaspaceShared::commit_shared_space_to(). 313 if (!_shared_vs.initialize(_shared_rs, 0)) { 314 vm_exit_during_initialization("Unable to allocate memory for shared space"); 315 } 316 317 _mc_region.init(&_shared_rs); 318 tty->print_cr("Allocated shared space: " SIZE_FORMAT " bytes at " PTR_FORMAT, 319 _shared_rs.size(), p2i(_shared_rs.base())); 320 } 321 322 void MetaspaceShared::commit_shared_space_to(char* newtop) { 323 assert(DumpSharedSpaces, "dump-time only"); 324 char* base = _shared_rs.base(); 325 size_t need_committed_size = newtop - base; 326 size_t has_committed_size = _shared_vs.committed_size(); 327 if (need_committed_size < has_committed_size) { 328 return; 329 } 330 331 size_t min_bytes = need_committed_size - has_committed_size; 332 size_t preferred_bytes = 1 * M; 333 size_t uncommitted = _shared_vs.reserved_size() - has_committed_size; 334 335 size_t commit = MAX2(min_bytes, preferred_bytes); 336 assert(commit <= uncommitted, "sanity"); 337 338 bool result = _shared_vs.expand_by(commit, false); 339 if (!result) { 340 vm_exit_during_initialization(err_msg("Failed to expand shared space to " SIZE_FORMAT " bytes", 341 need_committed_size)); 342 } 343 344 log_info(cds)("Expanding shared spaces by " SIZE_FORMAT_W(7) " bytes [total " SIZE_FORMAT_W(9) " bytes ending at %p]", 345 commit, _shared_vs.actual_committed_size(), _shared_vs.high()); 346 } 347 348 // Read/write a data stream for restoring/preserving metadata pointers and 349 // miscellaneous data from/to the shared archive file. 350 351 void MetaspaceShared::serialize(SerializeClosure* soc) { 352 int tag = 0; 353 soc->do_tag(--tag); 354 355 // Verify the sizes of various metadata in the system. 356 soc->do_tag(sizeof(Method)); 357 soc->do_tag(sizeof(ConstMethod)); 358 soc->do_tag(arrayOopDesc::base_offset_in_bytes(T_BYTE)); 359 soc->do_tag(sizeof(ConstantPool)); 360 soc->do_tag(sizeof(ConstantPoolCache)); 361 soc->do_tag(objArrayOopDesc::base_offset_in_bytes()); 362 soc->do_tag(typeArrayOopDesc::base_offset_in_bytes(T_BYTE)); 363 soc->do_tag(sizeof(Symbol)); 364 365 // Dump/restore miscellaneous metadata. 366 Universe::serialize(soc, true); 367 soc->do_tag(--tag); 368 369 // Dump/restore references to commonly used names and signatures. 370 vmSymbols::serialize(soc); 371 soc->do_tag(--tag); 372 373 // Dump/restore the symbol and string tables 374 SymbolTable::serialize(soc); 375 StringTable::serialize(soc); 376 soc->do_tag(--tag); 377 378 serialize_well_known_classes(soc); 379 soc->do_tag(--tag); 380 381 soc->do_tag(666); 382 } 383 384 void MetaspaceShared::serialize_well_known_classes(SerializeClosure* soc) { 385 java_lang_Class::serialize(soc); 386 java_lang_String::serialize(soc); 387 java_lang_System::serialize(soc); 388 java_lang_ClassLoader::serialize(soc); 389 java_lang_Throwable::serialize(soc); 390 java_lang_Thread::serialize(soc); 391 java_lang_ThreadGroup::serialize(soc); 392 java_lang_AssertionStatusDirectives::serialize(soc); 393 java_lang_ref_SoftReference::serialize(soc); 394 java_lang_invoke_MethodHandle::serialize(soc); 395 java_lang_invoke_DirectMethodHandle::serialize(soc); 396 java_lang_invoke_MemberName::serialize(soc); 397 java_lang_invoke_ResolvedMethodName::serialize(soc); 398 java_lang_invoke_LambdaForm::serialize(soc); 399 java_lang_invoke_MethodType::serialize(soc); 400 java_lang_invoke_CallSite::serialize(soc); 401 java_lang_invoke_MethodHandleNatives_CallSiteContext::serialize(soc); 402 java_security_AccessControlContext::serialize(soc); 403 java_lang_reflect_AccessibleObject::serialize(soc); 404 java_lang_reflect_Method::serialize(soc); 405 java_lang_reflect_Constructor::serialize(soc); 406 java_lang_reflect_Field::serialize(soc); 407 java_nio_Buffer::serialize(soc); 408 reflect_ConstantPool::serialize(soc); 409 reflect_UnsafeStaticFieldAccessorImpl::serialize(soc); 410 java_lang_reflect_Parameter::serialize(soc); 411 java_lang_Module::serialize(soc); 412 java_lang_StackTraceElement::serialize(soc); 413 java_lang_StackFrameInfo::serialize(soc); 414 java_lang_LiveStackFrameInfo::serialize(soc); 415 } 416 417 address MetaspaceShared::cds_i2i_entry_code_buffers(size_t total_size) { 418 if (DumpSharedSpaces) { 419 if (_cds_i2i_entry_code_buffers == NULL) { 420 _cds_i2i_entry_code_buffers = (address)misc_code_space_alloc(total_size); 421 _cds_i2i_entry_code_buffers_size = total_size; 422 } 423 } else if (UseSharedSpaces) { 424 assert(_cds_i2i_entry_code_buffers != NULL, "must already been initialized"); 425 } else { 426 return NULL; 427 } 428 429 assert(_cds_i2i_entry_code_buffers_size == total_size, "must not change"); 430 return _cds_i2i_entry_code_buffers; 431 } 432 433 // CDS code for dumping shared archive. 434 435 // Global object for holding classes that have been loaded. Since this 436 // is run at a safepoint just before exit, this is the entire set of classes. 437 static GrowableArray<Klass*>* _global_klass_objects; 438 439 static void collect_array_classes(Klass* k) { 440 _global_klass_objects->append_if_missing(k); 441 if (k->is_array_klass()) { 442 // Add in the array classes too 443 ArrayKlass* ak = ArrayKlass::cast(k); 444 Klass* h = ak->higher_dimension(); 445 if (h != NULL) { 446 h->array_klasses_do(collect_array_classes); 447 } 448 } 449 } 450 451 class CollectClassesClosure : public KlassClosure { 452 void do_klass(Klass* k) { 453 if (!UseAppCDS && !k->class_loader_data()->is_the_null_class_loader_data()) { 454 // AppCDS is not enabled. Let's omit non-boot classes. 455 return; 456 } 457 458 if (!(k->is_instance_klass() && InstanceKlass::cast(k)->is_in_error_state())) { 459 if (k->is_instance_klass() && InstanceKlass::cast(k)->signers() != NULL) { 460 // Mark any class with signers and don't add to the _global_klass_objects 461 k->set_has_signer_and_not_archived(); 462 } else { 463 _global_klass_objects->append_if_missing(k); 464 } 465 } 466 if (k->is_array_klass()) { 467 // Add in the array classes too 468 ArrayKlass* ak = ArrayKlass::cast(k); 469 Klass* h = ak->higher_dimension(); 470 if (h != NULL) { 471 h->array_klasses_do(collect_array_classes); 472 } 473 } 474 } 475 }; 476 477 static void remove_unshareable_in_classes() { 478 for (int i = 0; i < _global_klass_objects->length(); i++) { 479 Klass* k = _global_klass_objects->at(i); 480 if (!k->is_objArray_klass()) { 481 // InstanceKlass and TypeArrayKlass will in turn call remove_unshareable_info 482 // on their array classes. 483 assert(k->is_instance_klass() || k->is_typeArray_klass(), "must be"); 484 k->remove_unshareable_info(); 485 } 486 } 487 } 488 489 static void remove_java_mirror_in_classes() { 490 for (int i = 0; i < _global_klass_objects->length(); i++) { 491 Klass* k = _global_klass_objects->at(i); 492 if (!k->is_objArray_klass()) { 493 // InstanceKlass and TypeArrayKlass will in turn call remove_unshareable_info 494 // on their array classes. 495 assert(k->is_instance_klass() || k->is_typeArray_klass(), "must be"); 496 k->remove_java_mirror(); 497 } 498 } 499 } 500 501 static void clear_basic_type_mirrors() { 502 assert(!MetaspaceShared::is_heap_object_archiving_allowed(), "Sanity"); 503 Universe::set_int_mirror(NULL); 504 Universe::set_float_mirror(NULL); 505 Universe::set_double_mirror(NULL); 506 Universe::set_byte_mirror(NULL); 507 Universe::set_bool_mirror(NULL); 508 Universe::set_char_mirror(NULL); 509 Universe::set_long_mirror(NULL); 510 Universe::set_short_mirror(NULL); 511 Universe::set_void_mirror(NULL); 512 } 513 514 static void rewrite_nofast_bytecode(Method* method) { 515 BytecodeStream bcs(method); 516 while (!bcs.is_last_bytecode()) { 517 Bytecodes::Code opcode = bcs.next(); 518 switch (opcode) { 519 case Bytecodes::_getfield: *bcs.bcp() = Bytecodes::_nofast_getfield; break; 520 case Bytecodes::_putfield: *bcs.bcp() = Bytecodes::_nofast_putfield; break; 521 case Bytecodes::_aload_0: *bcs.bcp() = Bytecodes::_nofast_aload_0; break; 522 case Bytecodes::_iload: { 523 if (!bcs.is_wide()) { 524 *bcs.bcp() = Bytecodes::_nofast_iload; 525 } 526 break; 527 } 528 default: break; 529 } 530 } 531 } 532 533 // Walk all methods in the class list to ensure that they won't be modified at 534 // run time. This includes: 535 // [1] Rewrite all bytecodes as needed, so that the ConstMethod* will not be modified 536 // at run time by RewriteBytecodes/RewriteFrequentPairs 537 // [2] Assign a fingerprint, so one doesn't need to be assigned at run-time. 538 static void rewrite_nofast_bytecodes_and_calculate_fingerprints() { 539 for (int i = 0; i < _global_klass_objects->length(); i++) { 540 Klass* k = _global_klass_objects->at(i); 541 if (k->is_instance_klass()) { 542 InstanceKlass* ik = InstanceKlass::cast(k); 543 for (int i = 0; i < ik->methods()->length(); i++) { 544 Method* m = ik->methods()->at(i); 545 rewrite_nofast_bytecode(m); 546 Fingerprinter fp(m); 547 // The side effect of this call sets method's fingerprint field. 548 fp.fingerprint(); 549 } 550 } 551 } 552 } 553 554 static void relocate_cached_class_file() { 555 for (int i = 0; i < _global_klass_objects->length(); i++) { 556 Klass* k = _global_klass_objects->at(i); 557 if (k->is_instance_klass()) { 558 InstanceKlass* ik = InstanceKlass::cast(k); 559 JvmtiCachedClassFileData* p = ik->get_archived_class_data(); 560 if (p != NULL) { 561 int size = offset_of(JvmtiCachedClassFileData, data) + p->length; 562 JvmtiCachedClassFileData* q = (JvmtiCachedClassFileData*)_od_region.allocate(size); 563 q->length = p->length; 564 memcpy(q->data, p->data, p->length); 565 ik->set_archived_class_data(q); 566 } 567 } 568 } 569 } 570 571 NOT_PRODUCT( 572 static void assert_not_anonymous_class(InstanceKlass* k) { 573 assert(!(k->is_anonymous()), "cannot archive anonymous classes"); 574 } 575 576 // Anonymous classes are not stored inside any dictionaries. They are created by 577 // SystemDictionary::parse_stream() with a non-null host_klass. 578 static void assert_no_anonymoys_classes_in_dictionaries() { 579 ClassLoaderDataGraph::dictionary_classes_do(assert_not_anonymous_class); 580 }) 581 582 // Objects of the Metadata types (such as Klass and ConstantPool) have C++ vtables. 583 // (In GCC this is the field <Type>::_vptr, i.e., first word in the object.) 584 // 585 // Addresses of the vtables and the methods may be different across JVM runs, 586 // if libjvm.so is dynamically loaded at a different base address. 587 // 588 // To ensure that the Metadata objects in the CDS archive always have the correct vtable: 589 // 590 // + at dump time: we redirect the _vptr to point to our own vtables inside 591 // the CDS image 592 // + at run time: we clone the actual contents of the vtables from libjvm.so 593 // into our own tables. 594 595 // Currently, the archive contain ONLY the following types of objects that have C++ vtables. 596 #define CPP_VTABLE_PATCH_TYPES_DO(f) \ 597 f(ConstantPool) \ 598 f(InstanceKlass) \ 599 f(InstanceClassLoaderKlass) \ 600 f(InstanceMirrorKlass) \ 601 f(InstanceRefKlass) \ 602 f(Method) \ 603 f(ObjArrayKlass) \ 604 f(TypeArrayKlass) 605 606 class CppVtableInfo { 607 intptr_t _vtable_size; 608 intptr_t _cloned_vtable[1]; 609 public: 610 static int num_slots(int vtable_size) { 611 return 1 + vtable_size; // Need to add the space occupied by _vtable_size; 612 } 613 int vtable_size() { return int(uintx(_vtable_size)); } 614 void set_vtable_size(int n) { _vtable_size = intptr_t(n); } 615 intptr_t* cloned_vtable() { return &_cloned_vtable[0]; } 616 void zero() { memset(_cloned_vtable, 0, sizeof(intptr_t) * vtable_size()); } 617 // Returns the address of the next CppVtableInfo that can be placed immediately after this CppVtableInfo 618 static size_t byte_size(int vtable_size) { 619 CppVtableInfo i; 620 return pointer_delta(&i._cloned_vtable[vtable_size], &i, sizeof(u1)); 621 } 622 }; 623 624 template <class T> class CppVtableCloner : public T { 625 static intptr_t* vtable_of(Metadata& m) { 626 return *((intptr_t**)&m); 627 } 628 static CppVtableInfo* _info; 629 630 static int get_vtable_length(const char* name); 631 632 public: 633 // Allocate and initialize the C++ vtable, starting from top, but do not go past end. 634 static intptr_t* allocate(const char* name); 635 636 // Clone the vtable to ... 637 static intptr_t* clone_vtable(const char* name, CppVtableInfo* info); 638 639 static void zero_vtable_clone() { 640 assert(DumpSharedSpaces, "dump-time only"); 641 _info->zero(); 642 } 643 644 // Switch the vtable pointer to point to the cloned vtable. 645 static void patch(Metadata* obj) { 646 assert(DumpSharedSpaces, "dump-time only"); 647 *(void**)obj = (void*)(_info->cloned_vtable()); 648 } 649 650 static bool is_valid_shared_object(const T* obj) { 651 intptr_t* vptr = *(intptr_t**)obj; 652 return vptr == _info->cloned_vtable(); 653 } 654 }; 655 656 template <class T> CppVtableInfo* CppVtableCloner<T>::_info = NULL; 657 658 template <class T> 659 intptr_t* CppVtableCloner<T>::allocate(const char* name) { 660 assert(is_aligned(_md_region.top(), sizeof(intptr_t)), "bad alignment"); 661 int n = get_vtable_length(name); 662 _info = (CppVtableInfo*)_md_region.allocate(CppVtableInfo::byte_size(n), sizeof(intptr_t)); 663 _info->set_vtable_size(n); 664 665 intptr_t* p = clone_vtable(name, _info); 666 assert((char*)p == _md_region.top(), "must be"); 667 668 return p; 669 } 670 671 template <class T> 672 intptr_t* CppVtableCloner<T>::clone_vtable(const char* name, CppVtableInfo* info) { 673 if (!DumpSharedSpaces) { 674 assert(_info == 0, "_info is initialized only at dump time"); 675 _info = info; // Remember it -- it will be used by MetaspaceShared::is_valid_shared_method() 676 } 677 T tmp; // Allocate temporary dummy metadata object to get to the original vtable. 678 int n = info->vtable_size(); 679 intptr_t* srcvtable = vtable_of(tmp); 680 intptr_t* dstvtable = info->cloned_vtable(); 681 682 // We already checked (and, if necessary, adjusted n) when the vtables were allocated, so we are 683 // safe to do memcpy. 684 log_debug(cds, vtables)("Copying %3d vtable entries for %s", n, name); 685 memcpy(dstvtable, srcvtable, sizeof(intptr_t) * n); 686 return dstvtable + n; 687 } 688 689 // To determine the size of the vtable for each type, we use the following 690 // trick by declaring 2 subclasses: 691 // 692 // class CppVtableTesterA: public InstanceKlass {virtual int last_virtual_method() {return 1;} }; 693 // class CppVtableTesterB: public InstanceKlass {virtual void* last_virtual_method() {return NULL}; }; 694 // 695 // CppVtableTesterA and CppVtableTesterB's vtables have the following properties: 696 // - Their size (N+1) is exactly one more than the size of InstanceKlass's vtable (N) 697 // - The first N entries have are exactly the same as in InstanceKlass's vtable. 698 // - Their last entry is different. 699 // 700 // So to determine the value of N, we just walk CppVtableTesterA and CppVtableTesterB's tables 701 // and find the first entry that's different. 702 // 703 // This works on all C++ compilers supported by Oracle, but you may need to tweak it for more 704 // esoteric compilers. 705 706 template <class T> class CppVtableTesterB: public T { 707 public: 708 virtual int last_virtual_method() {return 1;} 709 }; 710 711 template <class T> class CppVtableTesterA : public T { 712 public: 713 virtual void* last_virtual_method() { 714 // Make this different than CppVtableTesterB::last_virtual_method so the C++ 715 // compiler/linker won't alias the two functions. 716 return NULL; 717 } 718 }; 719 720 template <class T> 721 int CppVtableCloner<T>::get_vtable_length(const char* name) { 722 CppVtableTesterA<T> a; 723 CppVtableTesterB<T> b; 724 725 intptr_t* avtable = vtable_of(a); 726 intptr_t* bvtable = vtable_of(b); 727 728 // Start at slot 1, because slot 0 may be RTTI (on Solaris/Sparc) 729 int vtable_len = 1; 730 for (; ; vtable_len++) { 731 if (avtable[vtable_len] != bvtable[vtable_len]) { 732 break; 733 } 734 } 735 log_debug(cds, vtables)("Found %3d vtable entries for %s", vtable_len, name); 736 737 return vtable_len; 738 } 739 740 #define ALLOC_CPP_VTABLE_CLONE(c) \ 741 CppVtableCloner<c>::allocate(#c); 742 743 #define CLONE_CPP_VTABLE(c) \ 744 p = CppVtableCloner<c>::clone_vtable(#c, (CppVtableInfo*)p); 745 746 #define ZERO_CPP_VTABLE(c) \ 747 CppVtableCloner<c>::zero_vtable_clone(); 748 749 // This can be called at both dump time and run time. 750 intptr_t* MetaspaceShared::clone_cpp_vtables(intptr_t* p) { 751 assert(DumpSharedSpaces || UseSharedSpaces, "sanity"); 752 CPP_VTABLE_PATCH_TYPES_DO(CLONE_CPP_VTABLE); 753 return p; 754 } 755 756 void MetaspaceShared::zero_cpp_vtable_clones_for_writing() { 757 assert(DumpSharedSpaces, "dump-time only"); 758 CPP_VTABLE_PATCH_TYPES_DO(ZERO_CPP_VTABLE); 759 } 760 761 // Allocate and initialize the C++ vtables, starting from top, but do not go past end. 762 void MetaspaceShared::allocate_cpp_vtable_clones() { 763 assert(DumpSharedSpaces, "dump-time only"); 764 // Layout (each slot is a intptr_t): 765 // [number of slots in the first vtable = n1] 766 // [ <n1> slots for the first vtable] 767 // [number of slots in the first second = n2] 768 // [ <n2> slots for the second vtable] 769 // ... 770 // The order of the vtables is the same as the CPP_VTAB_PATCH_TYPES_DO macro. 771 CPP_VTABLE_PATCH_TYPES_DO(ALLOC_CPP_VTABLE_CLONE); 772 } 773 774 // Switch the vtable pointer to point to the cloned vtable. We assume the 775 // vtable pointer is in first slot in object. 776 void MetaspaceShared::patch_cpp_vtable_pointers() { 777 int n = _global_klass_objects->length(); 778 for (int i = 0; i < n; i++) { 779 Klass* obj = _global_klass_objects->at(i); 780 if (obj->is_instance_klass()) { 781 InstanceKlass* ik = InstanceKlass::cast(obj); 782 if (ik->is_class_loader_instance_klass()) { 783 CppVtableCloner<InstanceClassLoaderKlass>::patch(ik); 784 } else if (ik->is_reference_instance_klass()) { 785 CppVtableCloner<InstanceRefKlass>::patch(ik); 786 } else if (ik->is_mirror_instance_klass()) { 787 CppVtableCloner<InstanceMirrorKlass>::patch(ik); 788 } else { 789 CppVtableCloner<InstanceKlass>::patch(ik); 790 } 791 ConstantPool* cp = ik->constants(); 792 CppVtableCloner<ConstantPool>::patch(cp); 793 for (int j = 0; j < ik->methods()->length(); j++) { 794 Method* m = ik->methods()->at(j); 795 CppVtableCloner<Method>::patch(m); 796 assert(CppVtableCloner<Method>::is_valid_shared_object(m), "must be"); 797 } 798 } else if (obj->is_objArray_klass()) { 799 CppVtableCloner<ObjArrayKlass>::patch(obj); 800 } else { 801 assert(obj->is_typeArray_klass(), "sanity"); 802 CppVtableCloner<TypeArrayKlass>::patch(obj); 803 } 804 } 805 } 806 807 bool MetaspaceShared::is_valid_shared_method(const Method* m) { 808 assert(is_in_shared_metaspace(m), "must be"); 809 return CppVtableCloner<Method>::is_valid_shared_object(m); 810 } 811 812 // Closure for serializing initialization data out to a data area to be 813 // written to the shared file. 814 815 class WriteClosure : public SerializeClosure { 816 private: 817 DumpRegion* _dump_region; 818 819 public: 820 WriteClosure(DumpRegion* r) { 821 _dump_region = r; 822 } 823 824 void do_ptr(void** p) { 825 _dump_region->append_intptr_t((intptr_t)*p); 826 } 827 828 void do_u4(u4* p) { 829 void* ptr = (void*)(uintx(*p)); 830 do_ptr(&ptr); 831 } 832 833 void do_tag(int tag) { 834 _dump_region->append_intptr_t((intptr_t)tag); 835 } 836 837 void do_oop(oop* o) { 838 if (*o == NULL) { 839 _dump_region->append_intptr_t(0); 840 } else { 841 assert(MetaspaceShared::is_heap_object_archiving_allowed(), 842 "Archiving heap object is not allowed"); 843 _dump_region->append_intptr_t( 844 (intptr_t)oopDesc::encode_heap_oop_not_null(*o)); 845 } 846 } 847 848 void do_region(u_char* start, size_t size) { 849 assert((intptr_t)start % sizeof(intptr_t) == 0, "bad alignment"); 850 assert(size % sizeof(intptr_t) == 0, "bad size"); 851 do_tag((int)size); 852 while (size > 0) { 853 _dump_region->append_intptr_t(*(intptr_t*)start); 854 start += sizeof(intptr_t); 855 size -= sizeof(intptr_t); 856 } 857 } 858 859 bool reading() const { return false; } 860 }; 861 862 // This is for dumping detailed statistics for the allocations 863 // in the shared spaces. 864 class DumpAllocStats : public ResourceObj { 865 public: 866 867 // Here's poor man's enum inheritance 868 #define SHAREDSPACE_OBJ_TYPES_DO(f) \ 869 METASPACE_OBJ_TYPES_DO(f) \ 870 f(SymbolHashentry) \ 871 f(SymbolBucket) \ 872 f(StringHashentry) \ 873 f(StringBucket) \ 874 f(Other) 875 876 enum Type { 877 // Types are MetaspaceObj::ClassType, MetaspaceObj::SymbolType, etc 878 SHAREDSPACE_OBJ_TYPES_DO(METASPACE_OBJ_TYPE_DECLARE) 879 _number_of_types 880 }; 881 882 static const char * type_name(Type type) { 883 switch(type) { 884 SHAREDSPACE_OBJ_TYPES_DO(METASPACE_OBJ_TYPE_NAME_CASE) 885 default: 886 ShouldNotReachHere(); 887 return NULL; 888 } 889 } 890 891 public: 892 enum { RO = 0, RW = 1 }; 893 894 int _counts[2][_number_of_types]; 895 int _bytes [2][_number_of_types]; 896 897 DumpAllocStats() { 898 memset(_counts, 0, sizeof(_counts)); 899 memset(_bytes, 0, sizeof(_bytes)); 900 }; 901 902 void record(MetaspaceObj::Type type, int byte_size, bool read_only) { 903 assert(int(type) >= 0 && type < MetaspaceObj::_number_of_types, "sanity"); 904 int which = (read_only) ? RO : RW; 905 _counts[which][type] ++; 906 _bytes [which][type] += byte_size; 907 } 908 909 void record_other_type(int byte_size, bool read_only) { 910 int which = (read_only) ? RO : RW; 911 _bytes [which][OtherType] += byte_size; 912 } 913 void print_stats(int ro_all, int rw_all, int mc_all, int md_all); 914 }; 915 916 void DumpAllocStats::print_stats(int ro_all, int rw_all, int mc_all, int md_all) { 917 // Calculate size of data that was not allocated by Metaspace::allocate() 918 MetaspaceSharedStats *stats = MetaspaceShared::stats(); 919 920 // symbols 921 _counts[RO][SymbolHashentryType] = stats->symbol.hashentry_count; 922 _bytes [RO][SymbolHashentryType] = stats->symbol.hashentry_bytes; 923 924 _counts[RO][SymbolBucketType] = stats->symbol.bucket_count; 925 _bytes [RO][SymbolBucketType] = stats->symbol.bucket_bytes; 926 927 // strings 928 _counts[RO][StringHashentryType] = stats->string.hashentry_count; 929 _bytes [RO][StringHashentryType] = stats->string.hashentry_bytes; 930 931 _counts[RO][StringBucketType] = stats->string.bucket_count; 932 _bytes [RO][StringBucketType] = stats->string.bucket_bytes; 933 934 // TODO: count things like dictionary, vtable, etc 935 _bytes[RW][OtherType] += mc_all + md_all; 936 rw_all += mc_all + md_all; // mc/md are mapped Read/Write 937 938 // prevent divide-by-zero 939 if (ro_all < 1) { 940 ro_all = 1; 941 } 942 if (rw_all < 1) { 943 rw_all = 1; 944 } 945 946 int all_ro_count = 0; 947 int all_ro_bytes = 0; 948 int all_rw_count = 0; 949 int all_rw_bytes = 0; 950 951 // To make fmt_stats be a syntactic constant (for format warnings), use #define. 952 #define fmt_stats "%-20s: %8d %10d %5.1f | %8d %10d %5.1f | %8d %10d %5.1f" 953 const char *sep = "--------------------+---------------------------+---------------------------+--------------------------"; 954 const char *hdr = " ro_cnt ro_bytes % | rw_cnt rw_bytes % | all_cnt all_bytes %"; 955 956 LogMessage(cds) msg; 957 958 msg.info("Detailed metadata info (excluding od/st regions; rw stats include md/mc regions):"); 959 msg.info("%s", hdr); 960 msg.info("%s", sep); 961 for (int type = 0; type < int(_number_of_types); type ++) { 962 const char *name = type_name((Type)type); 963 int ro_count = _counts[RO][type]; 964 int ro_bytes = _bytes [RO][type]; 965 int rw_count = _counts[RW][type]; 966 int rw_bytes = _bytes [RW][type]; 967 int count = ro_count + rw_count; 968 int bytes = ro_bytes + rw_bytes; 969 970 double ro_perc = percent_of(ro_bytes, ro_all); 971 double rw_perc = percent_of(rw_bytes, rw_all); 972 double perc = percent_of(bytes, ro_all + rw_all); 973 974 msg.info(fmt_stats, name, 975 ro_count, ro_bytes, ro_perc, 976 rw_count, rw_bytes, rw_perc, 977 count, bytes, perc); 978 979 all_ro_count += ro_count; 980 all_ro_bytes += ro_bytes; 981 all_rw_count += rw_count; 982 all_rw_bytes += rw_bytes; 983 } 984 985 int all_count = all_ro_count + all_rw_count; 986 int all_bytes = all_ro_bytes + all_rw_bytes; 987 988 double all_ro_perc = percent_of(all_ro_bytes, ro_all); 989 double all_rw_perc = percent_of(all_rw_bytes, rw_all); 990 double all_perc = percent_of(all_bytes, ro_all + rw_all); 991 992 msg.info("%s", sep); 993 msg.info(fmt_stats, "Total", 994 all_ro_count, all_ro_bytes, all_ro_perc, 995 all_rw_count, all_rw_bytes, all_rw_perc, 996 all_count, all_bytes, all_perc); 997 998 assert(all_ro_bytes == ro_all, "everything should have been counted"); 999 assert(all_rw_bytes == rw_all, "everything should have been counted"); 1000 1001 #undef fmt_stats 1002 } 1003 1004 // Populate the shared space. 1005 1006 class VM_PopulateDumpSharedSpace: public VM_Operation { 1007 private: 1008 GrowableArray<MemRegion> *_closed_archive_heap_regions; 1009 GrowableArray<MemRegion> *_open_archive_heap_regions; 1010 1011 void dump_java_heap_objects() NOT_CDS_JAVA_HEAP_RETURN; 1012 void dump_symbols(); 1013 char* dump_read_only_tables(); 1014 void print_region_stats(); 1015 void print_heap_region_stats(GrowableArray<MemRegion> *heap_mem, 1016 const char *name, const size_t total_size); 1017 public: 1018 1019 VMOp_Type type() const { return VMOp_PopulateDumpSharedSpace; } 1020 void doit(); // outline because gdb sucks 1021 static void write_region(FileMapInfo* mapinfo, int region, DumpRegion* space, bool read_only, bool allow_exec); 1022 bool allow_nested_vm_operations() const { return true; } 1023 }; // class VM_PopulateDumpSharedSpace 1024 1025 class SortedSymbolClosure: public SymbolClosure { 1026 GrowableArray<Symbol*> _symbols; 1027 virtual void do_symbol(Symbol** sym) { 1028 assert((*sym)->is_permanent(), "archived symbols must be permanent"); 1029 _symbols.append(*sym); 1030 } 1031 static int compare_symbols_by_address(Symbol** a, Symbol** b) { 1032 if (a[0] < b[0]) { 1033 return -1; 1034 } else if (a[0] == b[0]) { 1035 return 0; 1036 } else { 1037 return 1; 1038 } 1039 } 1040 1041 public: 1042 SortedSymbolClosure() { 1043 SymbolTable::symbols_do(this); 1044 _symbols.sort(compare_symbols_by_address); 1045 } 1046 GrowableArray<Symbol*>* get_sorted_symbols() { 1047 return &_symbols; 1048 } 1049 }; 1050 1051 // ArchiveCompactor -- 1052 // 1053 // This class is the central piece of shared archive compaction -- all metaspace data are 1054 // initially allocated outside of the shared regions. ArchiveCompactor copies the 1055 // metaspace data into their final location in the shared regions. 1056 1057 class ArchiveCompactor : AllStatic { 1058 static DumpAllocStats* _alloc_stats; 1059 static SortedSymbolClosure* _ssc; 1060 1061 static unsigned my_hash(const address& a) { 1062 return primitive_hash<address>(a); 1063 } 1064 static bool my_equals(const address& a0, const address& a1) { 1065 return primitive_equals<address>(a0, a1); 1066 } 1067 typedef ResourceHashtable< 1068 address, address, 1069 ArchiveCompactor::my_hash, // solaris compiler doesn't like: primitive_hash<address> 1070 ArchiveCompactor::my_equals, // solaris compiler doesn't like: primitive_equals<address> 1071 16384, ResourceObj::C_HEAP> RelocationTable; 1072 static RelocationTable* _new_loc_table; 1073 1074 public: 1075 static void initialize() { 1076 _alloc_stats = new(ResourceObj::C_HEAP, mtInternal)DumpAllocStats; 1077 _new_loc_table = new(ResourceObj::C_HEAP, mtInternal)RelocationTable; 1078 } 1079 static DumpAllocStats* alloc_stats() { 1080 return _alloc_stats; 1081 } 1082 1083 static void allocate(MetaspaceClosure::Ref* ref, bool read_only) { 1084 address obj = ref->obj(); 1085 int bytes = ref->size() * BytesPerWord; 1086 char* p; 1087 size_t alignment = BytesPerWord; 1088 char* oldtop; 1089 char* newtop; 1090 1091 if (read_only) { 1092 oldtop = _ro_region.top(); 1093 p = _ro_region.allocate(bytes, alignment); 1094 newtop = _ro_region.top(); 1095 } else { 1096 oldtop = _rw_region.top(); 1097 p = _rw_region.allocate(bytes, alignment); 1098 newtop = _rw_region.top(); 1099 } 1100 memcpy(p, obj, bytes); 1101 bool isnew = _new_loc_table->put(obj, (address)p); 1102 log_trace(cds)("Copy: " PTR_FORMAT " ==> " PTR_FORMAT " %d", p2i(obj), p2i(p), bytes); 1103 assert(isnew, "must be"); 1104 1105 _alloc_stats->record(ref->msotype(), int(newtop - oldtop), read_only); 1106 if (ref->msotype() == MetaspaceObj::SymbolType) { 1107 uintx delta = MetaspaceShared::object_delta(p); 1108 if (delta > MAX_SHARED_DELTA) { 1109 // This is just a sanity check and should not appear in any real world usage. This 1110 // happens only if you allocate more than 2GB of Symbols and would require 1111 // millions of shared classes. 1112 vm_exit_during_initialization("Too many Symbols in the CDS archive", 1113 "Please reduce the number of shared classes."); 1114 } 1115 } 1116 } 1117 1118 static address get_new_loc(MetaspaceClosure::Ref* ref) { 1119 address* pp = _new_loc_table->get(ref->obj()); 1120 assert(pp != NULL, "must be"); 1121 return *pp; 1122 } 1123 1124 private: 1125 // Makes a shallow copy of visited MetaspaceObj's 1126 class ShallowCopier: public UniqueMetaspaceClosure { 1127 bool _read_only; 1128 public: 1129 ShallowCopier(bool read_only) : _read_only(read_only) {} 1130 1131 virtual void do_unique_ref(Ref* ref, bool read_only) { 1132 if (read_only == _read_only) { 1133 allocate(ref, read_only); 1134 } 1135 } 1136 }; 1137 1138 // Relocate embedded pointers within a MetaspaceObj's shallow copy 1139 class ShallowCopyEmbeddedRefRelocator: public UniqueMetaspaceClosure { 1140 public: 1141 virtual void do_unique_ref(Ref* ref, bool read_only) { 1142 address new_loc = get_new_loc(ref); 1143 RefRelocator refer; 1144 ref->metaspace_pointers_do_at(&refer, new_loc); 1145 } 1146 }; 1147 1148 // Relocate a reference to point to its shallow copy 1149 class RefRelocator: public MetaspaceClosure { 1150 public: 1151 virtual bool do_ref(Ref* ref, bool read_only) { 1152 if (ref->not_null()) { 1153 ref->update(get_new_loc(ref)); 1154 } 1155 return false; // Do not recurse. 1156 } 1157 }; 1158 1159 #ifdef ASSERT 1160 class IsRefInArchiveChecker: public MetaspaceClosure { 1161 public: 1162 virtual bool do_ref(Ref* ref, bool read_only) { 1163 if (ref->not_null()) { 1164 char* obj = (char*)ref->obj(); 1165 assert(_ro_region.contains(obj) || _rw_region.contains(obj), 1166 "must be relocated to point to CDS archive"); 1167 } 1168 return false; // Do not recurse. 1169 } 1170 }; 1171 #endif 1172 1173 public: 1174 static void copy_and_compact() { 1175 // We should no longer allocate anything from the metaspace, so that 1176 // we can have a stable set of MetaspaceObjs to work with. 1177 Metaspace::freeze(); 1178 1179 ResourceMark rm; 1180 SortedSymbolClosure the_ssc; // StackObj 1181 _ssc = &the_ssc; 1182 1183 tty->print_cr("Scanning all metaspace objects ... "); 1184 { 1185 // allocate and shallow-copy RW objects, immediately following the MC region 1186 tty->print_cr("Allocating RW objects ... "); 1187 _mc_region.pack(&_rw_region); 1188 1189 ResourceMark rm; 1190 ShallowCopier rw_copier(false); 1191 iterate_roots(&rw_copier); 1192 } 1193 { 1194 // allocate and shallow-copy of RO object, immediately following the RW region 1195 tty->print_cr("Allocating RO objects ... "); 1196 _rw_region.pack(&_ro_region); 1197 1198 ResourceMark rm; 1199 ShallowCopier ro_copier(true); 1200 iterate_roots(&ro_copier); 1201 } 1202 { 1203 tty->print_cr("Relocating embedded pointers ... "); 1204 ResourceMark rm; 1205 ShallowCopyEmbeddedRefRelocator emb_reloc; 1206 iterate_roots(&emb_reloc); 1207 } 1208 { 1209 tty->print_cr("Relocating external roots ... "); 1210 ResourceMark rm; 1211 RefRelocator ext_reloc; 1212 iterate_roots(&ext_reloc); 1213 } 1214 1215 #ifdef ASSERT 1216 { 1217 tty->print_cr("Verifying external roots ... "); 1218 ResourceMark rm; 1219 IsRefInArchiveChecker checker; 1220 iterate_roots(&checker); 1221 } 1222 #endif 1223 1224 1225 // cleanup 1226 _ssc = NULL; 1227 } 1228 1229 // We must relocate the System::_well_known_klasses only after we have copied the 1230 // java objects in during dump_java_heap_objects(): during the object copy, we operate on 1231 // old objects which assert that their klass is the original klass. 1232 static void relocate_well_known_klasses() { 1233 { 1234 tty->print_cr("Relocating SystemDictionary::_well_known_klasses[] ... "); 1235 ResourceMark rm; 1236 RefRelocator ext_reloc; 1237 SystemDictionary::well_known_klasses_do(&ext_reloc); 1238 } 1239 // NOTE: after this point, we shouldn't have any globals that can reach the old 1240 // objects. 1241 1242 // We cannot use any of the objects in the heap anymore (except for the objects 1243 // in the CDS shared string regions) because their headers no longer point to 1244 // valid Klasses. 1245 } 1246 1247 static void iterate_roots(MetaspaceClosure* it) { 1248 GrowableArray<Symbol*>* symbols = _ssc->get_sorted_symbols(); 1249 for (int i=0; i<symbols->length(); i++) { 1250 it->push(symbols->adr_at(i)); 1251 } 1252 if (_global_klass_objects != NULL) { 1253 // Need to fix up the pointers 1254 for (int i = 0; i < _global_klass_objects->length(); i++) { 1255 // NOTE -- this requires that the vtable is NOT yet patched, or else we are hosed. 1256 it->push(_global_klass_objects->adr_at(i)); 1257 } 1258 } 1259 FileMapInfo::metaspace_pointers_do(it); 1260 SystemDictionary::classes_do(it); 1261 Universe::metaspace_pointers_do(it); 1262 SymbolTable::metaspace_pointers_do(it); 1263 vmSymbols::metaspace_pointers_do(it); 1264 } 1265 1266 static Klass* get_relocated_klass(Klass* orig_klass) { 1267 assert(DumpSharedSpaces, "dump time only"); 1268 address* pp = _new_loc_table->get((address)orig_klass); 1269 assert(pp != NULL, "must be"); 1270 Klass* klass = (Klass*)(*pp); 1271 assert(klass->is_klass(), "must be"); 1272 return klass; 1273 } 1274 }; 1275 1276 DumpAllocStats* ArchiveCompactor::_alloc_stats; 1277 SortedSymbolClosure* ArchiveCompactor::_ssc; 1278 ArchiveCompactor::RelocationTable* ArchiveCompactor::_new_loc_table; 1279 1280 void VM_PopulateDumpSharedSpace::write_region(FileMapInfo* mapinfo, int region_idx, 1281 DumpRegion* dump_region, bool read_only, bool allow_exec) { 1282 mapinfo->write_region(region_idx, dump_region->base(), dump_region->used(), read_only, allow_exec); 1283 } 1284 1285 void VM_PopulateDumpSharedSpace::dump_symbols() { 1286 tty->print_cr("Dumping symbol table ..."); 1287 1288 NOT_PRODUCT(SymbolTable::verify()); 1289 SymbolTable::write_to_archive(); 1290 } 1291 1292 char* VM_PopulateDumpSharedSpace::dump_read_only_tables() { 1293 char* oldtop = _ro_region.top(); 1294 // Reorder the system dictionary. Moving the symbols affects 1295 // how the hash table indices are calculated. 1296 SystemDictionary::reorder_dictionary_for_sharing(); 1297 1298 tty->print("Removing java_mirror ... "); 1299 if (!MetaspaceShared::is_heap_object_archiving_allowed()) { 1300 clear_basic_type_mirrors(); 1301 } 1302 remove_java_mirror_in_classes(); 1303 tty->print_cr("done. "); 1304 NOT_PRODUCT(SystemDictionary::verify();) 1305 1306 size_t buckets_bytes = SystemDictionary::count_bytes_for_buckets(); 1307 char* buckets_top = _ro_region.allocate(buckets_bytes, sizeof(intptr_t)); 1308 SystemDictionary::copy_buckets(buckets_top, _ro_region.top()); 1309 1310 size_t table_bytes = SystemDictionary::count_bytes_for_table(); 1311 char* table_top = _ro_region.allocate(table_bytes, sizeof(intptr_t)); 1312 SystemDictionary::copy_table(table_top, _ro_region.top()); 1313 1314 // Write the other data to the output array. 1315 WriteClosure wc(&_ro_region); 1316 MetaspaceShared::serialize(&wc); 1317 1318 char* newtop = _ro_region.top(); 1319 ArchiveCompactor::alloc_stats()->record_other_type(int(newtop - oldtop), true); 1320 return buckets_top; 1321 } 1322 1323 void VM_PopulateDumpSharedSpace::doit() { 1324 Thread* THREAD = VMThread::vm_thread(); 1325 1326 NOT_PRODUCT(SystemDictionary::verify();) 1327 // The following guarantee is meant to ensure that no loader constraints 1328 // exist yet, since the constraints table is not shared. This becomes 1329 // more important now that we don't re-initialize vtables/itables for 1330 // shared classes at runtime, where constraints were previously created. 1331 guarantee(SystemDictionary::constraints()->number_of_entries() == 0, 1332 "loader constraints are not saved"); 1333 guarantee(SystemDictionary::placeholders()->number_of_entries() == 0, 1334 "placeholders are not saved"); 1335 // Revisit and implement this if we prelink method handle call sites: 1336 guarantee(SystemDictionary::invoke_method_table() == NULL || 1337 SystemDictionary::invoke_method_table()->number_of_entries() == 0, 1338 "invoke method table is not saved"); 1339 1340 // At this point, many classes have been loaded. 1341 // Gather systemDictionary classes in a global array and do everything to 1342 // that so we don't have to walk the SystemDictionary again. 1343 _global_klass_objects = new GrowableArray<Klass*>(1000); 1344 CollectClassesClosure collect_classes; 1345 ClassLoaderDataGraph::loaded_classes_do(&collect_classes); 1346 1347 tty->print_cr("Number of classes %d", _global_klass_objects->length()); 1348 { 1349 int num_type_array = 0, num_obj_array = 0, num_inst = 0; 1350 for (int i = 0; i < _global_klass_objects->length(); i++) { 1351 Klass* k = _global_klass_objects->at(i); 1352 if (k->is_instance_klass()) { 1353 num_inst ++; 1354 } else if (k->is_objArray_klass()) { 1355 num_obj_array ++; 1356 } else { 1357 assert(k->is_typeArray_klass(), "sanity"); 1358 num_type_array ++; 1359 } 1360 } 1361 tty->print_cr(" instance classes = %5d", num_inst); 1362 tty->print_cr(" obj array classes = %5d", num_obj_array); 1363 tty->print_cr(" type array classes = %5d", num_type_array); 1364 } 1365 1366 // Ensure the ConstMethods won't be modified at run-time 1367 tty->print("Updating ConstMethods ... "); 1368 rewrite_nofast_bytecodes_and_calculate_fingerprints(); 1369 tty->print_cr("done. "); 1370 1371 // Move classes from platform/system dictionaries into the boot dictionary 1372 SystemDictionary::combine_shared_dictionaries(); 1373 1374 // Remove all references outside the metadata 1375 tty->print("Removing unshareable information ... "); 1376 remove_unshareable_in_classes(); 1377 tty->print_cr("done. "); 1378 1379 // We don't support archiving anonymous classes. Verify that they are not stored in 1380 // the any dictionaries. 1381 NOT_PRODUCT(assert_no_anonymoys_classes_in_dictionaries()); 1382 1383 SystemDictionaryShared::finalize_verification_constraints(); 1384 1385 ArchiveCompactor::initialize(); 1386 ArchiveCompactor::copy_and_compact(); 1387 1388 dump_symbols(); 1389 1390 // Dump supported java heap objects 1391 _closed_archive_heap_regions = NULL; 1392 _open_archive_heap_regions = NULL; 1393 dump_java_heap_objects(); 1394 1395 ArchiveCompactor::relocate_well_known_klasses(); 1396 1397 char* read_only_tables_start = dump_read_only_tables(); 1398 _ro_region.pack(&_md_region); 1399 1400 char* vtbl_list = _md_region.top(); 1401 MetaspaceShared::allocate_cpp_vtable_clones(); 1402 _md_region.pack(&_od_region); 1403 1404 // Relocate the archived class file data into the od region 1405 relocate_cached_class_file(); 1406 _od_region.pack(); 1407 1408 // The 5 core spaces are allocated consecutively mc->rw->ro->md->od, so there total size 1409 // is just the spaces between the two ends. 1410 size_t core_spaces_size = _od_region.end() - _mc_region.base(); 1411 assert(core_spaces_size == (size_t)align_up(core_spaces_size, Metaspace::reserve_alignment()), 1412 "should already be aligned"); 1413 1414 // During patching, some virtual methods may be called, so at this point 1415 // the vtables must contain valid methods (as filled in by CppVtableCloner::allocate). 1416 MetaspaceShared::patch_cpp_vtable_pointers(); 1417 1418 // The vtable clones contain addresses of the current process. 1419 // We don't want to write these addresses into the archive. 1420 MetaspaceShared::zero_cpp_vtable_clones_for_writing(); 1421 1422 // Create and write the archive file that maps the shared spaces. 1423 1424 FileMapInfo* mapinfo = new FileMapInfo(); 1425 mapinfo->populate_header(os::vm_allocation_granularity()); 1426 mapinfo->set_read_only_tables_start(read_only_tables_start); 1427 mapinfo->set_misc_data_patching_start(vtbl_list); 1428 mapinfo->set_cds_i2i_entry_code_buffers(MetaspaceShared::cds_i2i_entry_code_buffers()); 1429 mapinfo->set_cds_i2i_entry_code_buffers_size(MetaspaceShared::cds_i2i_entry_code_buffers_size()); 1430 mapinfo->set_core_spaces_size(core_spaces_size); 1431 1432 for (int pass=1; pass<=2; pass++) { 1433 if (pass == 1) { 1434 // The first pass doesn't actually write the data to disk. All it 1435 // does is to update the fields in the mapinfo->_header. 1436 } else { 1437 // After the first pass, the contents of mapinfo->_header are finalized, 1438 // so we can compute the header's CRC, and write the contents of the header 1439 // and the regions into disk. 1440 mapinfo->open_for_write(); 1441 mapinfo->set_header_crc(mapinfo->compute_header_crc()); 1442 } 1443 mapinfo->write_header(); 1444 1445 // NOTE: md contains the trampoline code for method entries, which are patched at run time, 1446 // so it needs to be read/write. 1447 write_region(mapinfo, MetaspaceShared::mc, &_mc_region, /*read_only=*/false,/*allow_exec=*/true); 1448 write_region(mapinfo, MetaspaceShared::rw, &_rw_region, /*read_only=*/false,/*allow_exec=*/false); 1449 write_region(mapinfo, MetaspaceShared::ro, &_ro_region, /*read_only=*/true, /*allow_exec=*/false); 1450 write_region(mapinfo, MetaspaceShared::md, &_md_region, /*read_only=*/false,/*allow_exec=*/false); 1451 write_region(mapinfo, MetaspaceShared::od, &_od_region, /*read_only=*/true, /*allow_exec=*/false); 1452 1453 _total_string_region_size = mapinfo->write_archive_heap_regions( 1454 _closed_archive_heap_regions, 1455 MetaspaceShared::first_string, 1456 MetaspaceShared::max_strings); 1457 _total_open_archive_region_size = mapinfo->write_archive_heap_regions( 1458 _open_archive_heap_regions, 1459 MetaspaceShared::first_open_archive_heap_region, 1460 MetaspaceShared::max_open_archive_heap_region); 1461 } 1462 1463 mapinfo->close(); 1464 1465 // Restore the vtable in case we invoke any virtual methods. 1466 MetaspaceShared::clone_cpp_vtables((intptr_t*)vtbl_list); 1467 1468 print_region_stats(); 1469 1470 if (log_is_enabled(Info, cds)) { 1471 ArchiveCompactor::alloc_stats()->print_stats(int(_ro_region.used()), int(_rw_region.used()), 1472 int(_mc_region.used()), int(_md_region.used())); 1473 } 1474 1475 if (PrintSystemDictionaryAtExit) { 1476 SystemDictionary::print(); 1477 } 1478 // There may be other pending VM operations that operate on the InstanceKlasses, 1479 // which will fail because InstanceKlasses::remove_unshareable_info() 1480 // has been called. Forget these operations and exit the VM directly. 1481 vm_direct_exit(0); 1482 } 1483 1484 void VM_PopulateDumpSharedSpace::print_region_stats() { 1485 // Print statistics of all the regions 1486 const size_t total_reserved = _ro_region.reserved() + _rw_region.reserved() + 1487 _mc_region.reserved() + _md_region.reserved() + 1488 _od_region.reserved() + 1489 _total_string_region_size + 1490 _total_open_archive_region_size; 1491 const size_t total_bytes = _ro_region.used() + _rw_region.used() + 1492 _mc_region.used() + _md_region.used() + 1493 _od_region.used() + 1494 _total_string_region_size + 1495 _total_open_archive_region_size; 1496 const double total_u_perc = percent_of(total_bytes, total_reserved); 1497 1498 _mc_region.print(total_reserved); 1499 _rw_region.print(total_reserved); 1500 _ro_region.print(total_reserved); 1501 _md_region.print(total_reserved); 1502 _od_region.print(total_reserved); 1503 print_heap_region_stats(_closed_archive_heap_regions, "st", total_reserved); 1504 print_heap_region_stats(_open_archive_heap_regions, "oa", total_reserved); 1505 1506 tty->print_cr("total : " SIZE_FORMAT_W(9) " [100.0%% of total] out of " SIZE_FORMAT_W(9) " bytes [%5.1f%% used]", 1507 total_bytes, total_reserved, total_u_perc); 1508 } 1509 1510 void VM_PopulateDumpSharedSpace::print_heap_region_stats(GrowableArray<MemRegion> *heap_mem, 1511 const char *name, const size_t total_size) { 1512 int arr_len = heap_mem == NULL ? 0 : heap_mem->length(); 1513 for (int i = 0; i < arr_len; i++) { 1514 char* start = (char*)heap_mem->at(i).start(); 1515 size_t size = heap_mem->at(i).byte_size(); 1516 char* top = start + size; 1517 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, 1518 name, i, size, size/double(total_size)*100.0, size, p2i(start)); 1519 1520 } 1521 } 1522 1523 // Update a Java object to point its Klass* to the new location after 1524 // shared archive has been compacted. 1525 void MetaspaceShared::relocate_klass_ptr(oop o) { 1526 assert(DumpSharedSpaces, "sanity"); 1527 Klass* k = ArchiveCompactor::get_relocated_klass(o->klass()); 1528 o->set_klass(k); 1529 } 1530 1531 Klass* MetaspaceShared::get_relocated_klass(Klass *k) { 1532 assert(DumpSharedSpaces, "sanity"); 1533 return ArchiveCompactor::get_relocated_klass(k); 1534 } 1535 1536 class LinkSharedClassesClosure : public KlassClosure { 1537 Thread* THREAD; 1538 bool _made_progress; 1539 public: 1540 LinkSharedClassesClosure(Thread* thread) : THREAD(thread), _made_progress(false) {} 1541 1542 void reset() { _made_progress = false; } 1543 bool made_progress() const { return _made_progress; } 1544 1545 void do_klass(Klass* k) { 1546 if (k->is_instance_klass()) { 1547 InstanceKlass* ik = InstanceKlass::cast(k); 1548 // Link the class to cause the bytecodes to be rewritten and the 1549 // cpcache to be created. Class verification is done according 1550 // to -Xverify setting. 1551 _made_progress |= MetaspaceShared::try_link_class(ik, THREAD); 1552 guarantee(!HAS_PENDING_EXCEPTION, "exception in link_class"); 1553 1554 ik->constants()->resolve_class_constants(THREAD); 1555 } 1556 } 1557 }; 1558 1559 class CheckSharedClassesClosure : public KlassClosure { 1560 bool _made_progress; 1561 public: 1562 CheckSharedClassesClosure() : _made_progress(false) {} 1563 1564 void reset() { _made_progress = false; } 1565 bool made_progress() const { return _made_progress; } 1566 void do_klass(Klass* k) { 1567 if (k->is_instance_klass() && InstanceKlass::cast(k)->check_sharing_error_state()) { 1568 _made_progress = true; 1569 } 1570 } 1571 }; 1572 1573 void MetaspaceShared::check_shared_class_loader_type(Klass* k) { 1574 if (k->is_instance_klass()) { 1575 InstanceKlass* ik = InstanceKlass::cast(k); 1576 u2 loader_type = ik->loader_type(); 1577 ResourceMark rm; 1578 guarantee(loader_type != 0, 1579 "Class loader type is not set for this class %s", ik->name()->as_C_string()); 1580 } 1581 } 1582 1583 void MetaspaceShared::link_and_cleanup_shared_classes(TRAPS) { 1584 // We need to iterate because verification may cause additional classes 1585 // to be loaded. 1586 LinkSharedClassesClosure link_closure(THREAD); 1587 do { 1588 link_closure.reset(); 1589 ClassLoaderDataGraph::loaded_classes_do(&link_closure); 1590 guarantee(!HAS_PENDING_EXCEPTION, "exception in link_class"); 1591 } while (link_closure.made_progress()); 1592 1593 if (_has_error_classes) { 1594 // Mark all classes whose super class or interfaces failed verification. 1595 CheckSharedClassesClosure check_closure; 1596 do { 1597 // Not completely sure if we need to do this iteratively. Anyway, 1598 // we should come here only if there are unverifiable classes, which 1599 // shouldn't happen in normal cases. So better safe than sorry. 1600 check_closure.reset(); 1601 ClassLoaderDataGraph::loaded_classes_do(&check_closure); 1602 } while (check_closure.made_progress()); 1603 1604 if (IgnoreUnverifiableClassesDuringDump) { 1605 // This is useful when running JCK or SQE tests. You should not 1606 // enable this when running real apps. 1607 SystemDictionary::remove_classes_in_error_state(); 1608 } else { 1609 tty->print_cr("Please remove the unverifiable classes from your class list and try again"); 1610 exit(1); 1611 } 1612 } 1613 } 1614 1615 void MetaspaceShared::prepare_for_dumping() { 1616 Arguments::check_unsupported_dumping_properties(); 1617 ClassLoader::initialize_shared_path(); 1618 FileMapInfo::allocate_classpath_entry_table(); 1619 } 1620 1621 // Preload classes from a list, populate the shared spaces and dump to a 1622 // file. 1623 void MetaspaceShared::preload_and_dump(TRAPS) { 1624 { TraceTime timer("Dump Shared Spaces", TRACETIME_LOG(Info, startuptime)); 1625 ResourceMark rm; 1626 char class_list_path_str[JVM_MAXPATHLEN]; 1627 // Preload classes to be shared. 1628 // Should use some os:: method rather than fopen() here. aB. 1629 const char* class_list_path; 1630 if (SharedClassListFile == NULL) { 1631 // Construct the path to the class list (in jre/lib) 1632 // Walk up two directories from the location of the VM and 1633 // optionally tack on "lib" (depending on platform) 1634 os::jvm_path(class_list_path_str, sizeof(class_list_path_str)); 1635 for (int i = 0; i < 3; i++) { 1636 char *end = strrchr(class_list_path_str, *os::file_separator()); 1637 if (end != NULL) *end = '\0'; 1638 } 1639 int class_list_path_len = (int)strlen(class_list_path_str); 1640 if (class_list_path_len >= 3) { 1641 if (strcmp(class_list_path_str + class_list_path_len - 3, "lib") != 0) { 1642 if (class_list_path_len < JVM_MAXPATHLEN - 4) { 1643 jio_snprintf(class_list_path_str + class_list_path_len, 1644 sizeof(class_list_path_str) - class_list_path_len, 1645 "%slib", os::file_separator()); 1646 class_list_path_len += 4; 1647 } 1648 } 1649 } 1650 if (class_list_path_len < JVM_MAXPATHLEN - 10) { 1651 jio_snprintf(class_list_path_str + class_list_path_len, 1652 sizeof(class_list_path_str) - class_list_path_len, 1653 "%sclasslist", os::file_separator()); 1654 } 1655 class_list_path = class_list_path_str; 1656 } else { 1657 class_list_path = SharedClassListFile; 1658 } 1659 1660 tty->print_cr("Loading classes to share ..."); 1661 _has_error_classes = false; 1662 int class_count = preload_classes(class_list_path, THREAD); 1663 if (ExtraSharedClassListFile) { 1664 class_count += preload_classes(ExtraSharedClassListFile, THREAD); 1665 } 1666 tty->print_cr("Loading classes to share: done."); 1667 1668 log_info(cds)("Shared spaces: preloaded %d classes", class_count); 1669 1670 // Rewrite and link classes 1671 tty->print_cr("Rewriting and linking classes ..."); 1672 1673 // Link any classes which got missed. This would happen if we have loaded classes that 1674 // were not explicitly specified in the classlist. E.g., if an interface implemented by class K 1675 // fails verification, all other interfaces that were not specified in the classlist but 1676 // are implemented by K are not verified. 1677 link_and_cleanup_shared_classes(CATCH); 1678 tty->print_cr("Rewriting and linking classes: done"); 1679 1680 SystemDictionary::clear_invoke_method_table(); 1681 1682 VM_PopulateDumpSharedSpace op; 1683 VMThread::execute(&op); 1684 } 1685 } 1686 1687 1688 int MetaspaceShared::preload_classes(const char* class_list_path, TRAPS) { 1689 ClassListParser parser(class_list_path); 1690 int class_count = 0; 1691 1692 while (parser.parse_one_line()) { 1693 Klass* klass = ClassLoaderExt::load_one_class(&parser, THREAD); 1694 if (HAS_PENDING_EXCEPTION) { 1695 if (klass == NULL && 1696 (PENDING_EXCEPTION->klass()->name() == vmSymbols::java_lang_ClassNotFoundException())) { 1697 // print a warning only when the pending exception is class not found 1698 tty->print_cr("Preload Warning: Cannot find %s", parser.current_class_name()); 1699 } 1700 CLEAR_PENDING_EXCEPTION; 1701 } 1702 if (klass != NULL) { 1703 if (log_is_enabled(Trace, cds)) { 1704 ResourceMark rm; 1705 log_trace(cds)("Shared spaces preloaded: %s", klass->external_name()); 1706 } 1707 1708 if (klass->is_instance_klass()) { 1709 InstanceKlass* ik = InstanceKlass::cast(klass); 1710 1711 // Link the class to cause the bytecodes to be rewritten and the 1712 // cpcache to be created. The linking is done as soon as classes 1713 // are loaded in order that the related data structures (klass and 1714 // cpCache) are located together. 1715 try_link_class(ik, THREAD); 1716 guarantee(!HAS_PENDING_EXCEPTION, "exception in link_class"); 1717 } 1718 1719 class_count++; 1720 } 1721 } 1722 1723 return class_count; 1724 } 1725 1726 // Returns true if the class's status has changed 1727 bool MetaspaceShared::try_link_class(InstanceKlass* ik, TRAPS) { 1728 assert(DumpSharedSpaces, "should only be called during dumping"); 1729 if (ik->init_state() < InstanceKlass::linked) { 1730 bool saved = BytecodeVerificationLocal; 1731 if (!(ik->is_shared_boot_class())) { 1732 // The verification decision is based on BytecodeVerificationRemote 1733 // for non-system classes. Since we are using the NULL classloader 1734 // to load non-system classes during dumping, we need to temporarily 1735 // change BytecodeVerificationLocal to be the same as 1736 // BytecodeVerificationRemote. Note this can cause the parent system 1737 // classes also being verified. The extra overhead is acceptable during 1738 // dumping. 1739 BytecodeVerificationLocal = BytecodeVerificationRemote; 1740 } 1741 ik->link_class(THREAD); 1742 if (HAS_PENDING_EXCEPTION) { 1743 ResourceMark rm; 1744 tty->print_cr("Preload Warning: Verification failed for %s", 1745 ik->external_name()); 1746 CLEAR_PENDING_EXCEPTION; 1747 ik->set_in_error_state(); 1748 _has_error_classes = true; 1749 } 1750 BytecodeVerificationLocal = saved; 1751 return true; 1752 } else { 1753 return false; 1754 } 1755 } 1756 1757 #if INCLUDE_CDS_JAVA_HEAP 1758 void VM_PopulateDumpSharedSpace::dump_java_heap_objects() { 1759 if (!MetaspaceShared::is_heap_object_archiving_allowed()) { 1760 if (log_is_enabled(Info, cds)) { 1761 log_info(cds)( 1762 "Archived java heap is not supported as UseG1GC, " 1763 "UseCompressedOops and UseCompressedClassPointers are required." 1764 "Current settings: UseG1GC=%s, UseCompressedOops=%s, UseCompressedClassPointers=%s.", 1765 BOOL_TO_STR(UseG1GC), BOOL_TO_STR(UseCompressedOops), 1766 BOOL_TO_STR(UseCompressedClassPointers)); 1767 } 1768 return; 1769 } 1770 1771 { 1772 NoSafepointVerifier nsv; 1773 1774 // Cache for recording where the archived objects are copied to 1775 MetaspaceShared::create_archive_object_cache(); 1776 1777 tty->print_cr("Dumping objects to closed archive heap region ..."); 1778 NOT_PRODUCT(StringTable::verify()); 1779 // The closed space has maximum two regions. See FileMapInfo::write_archive_heap_regions() for details. 1780 _closed_archive_heap_regions = new GrowableArray<MemRegion>(2); 1781 MetaspaceShared::dump_closed_archive_heap_objects(_closed_archive_heap_regions); 1782 1783 tty->print_cr("Dumping objects to open archive heap region ..."); 1784 _open_archive_heap_regions = new GrowableArray<MemRegion>(2); 1785 MetaspaceShared::dump_open_archive_heap_objects(_open_archive_heap_regions); 1786 1787 MetaspaceShared::destroy_archive_object_cache(); 1788 } 1789 1790 G1HeapVerifier::verify_archive_regions(); 1791 } 1792 1793 void MetaspaceShared::dump_closed_archive_heap_objects( 1794 GrowableArray<MemRegion> * closed_archive) { 1795 assert(is_heap_object_archiving_allowed(), "Cannot dump java heap objects"); 1796 1797 Thread* THREAD = Thread::current(); 1798 G1CollectedHeap::heap()->begin_archive_alloc_range(); 1799 1800 // Archive interned string objects 1801 StringTable::write_to_archive(closed_archive); 1802 1803 G1CollectedHeap::heap()->end_archive_alloc_range(closed_archive, 1804 os::vm_allocation_granularity()); 1805 } 1806 1807 void MetaspaceShared::dump_open_archive_heap_objects( 1808 GrowableArray<MemRegion> * open_archive) { 1809 assert(UseG1GC, "Only support G1 GC"); 1810 assert(UseCompressedOops && UseCompressedClassPointers, 1811 "Only support UseCompressedOops and UseCompressedClassPointers enabled"); 1812 1813 Thread* THREAD = Thread::current(); 1814 G1CollectedHeap::heap()->begin_archive_alloc_range(true /* open */); 1815 1816 java_lang_Class::archive_basic_type_mirrors(THREAD); 1817 1818 MetaspaceShared::archive_klass_objects(THREAD); 1819 1820 G1CollectedHeap::heap()->end_archive_alloc_range(open_archive, 1821 os::vm_allocation_granularity()); 1822 } 1823 1824 MetaspaceShared::ArchivedObjectCache* MetaspaceShared::_archive_object_cache = NULL; 1825 oop MetaspaceShared::find_archived_heap_object(oop obj) { 1826 assert(DumpSharedSpaces, "dump-time only"); 1827 ArchivedObjectCache* cache = MetaspaceShared::archive_object_cache(); 1828 oop* p = cache->get(obj); 1829 if (p != NULL) { 1830 return *p; 1831 } else { 1832 return NULL; 1833 } 1834 } 1835 1836 oop MetaspaceShared::archive_heap_object(oop obj, Thread* THREAD) { 1837 assert(DumpSharedSpaces, "dump-time only"); 1838 1839 oop ao = find_archived_heap_object(obj); 1840 if (ao != NULL) { 1841 // already archived 1842 return ao; 1843 } 1844 1845 int len = obj->size(); 1846 if (G1CollectedHeap::heap()->is_archive_alloc_too_large(len)) { 1847 return NULL; 1848 } 1849 1850 int hash = obj->identity_hash(); 1851 oop archived_oop = (oop)G1CollectedHeap::heap()->archive_mem_allocate(len); 1852 if (archived_oop != NULL) { 1853 Copy::aligned_disjoint_words((HeapWord*)obj, (HeapWord*)archived_oop, len); 1854 relocate_klass_ptr(archived_oop); 1855 ArchivedObjectCache* cache = MetaspaceShared::archive_object_cache(); 1856 cache->put(obj, archived_oop); 1857 } 1858 log_debug(cds)("Archived heap object " PTR_FORMAT " ==> " PTR_FORMAT, 1859 p2i(obj), p2i(archived_oop)); 1860 return archived_oop; 1861 } 1862 1863 void MetaspaceShared::archive_klass_objects(Thread* THREAD) { 1864 int i; 1865 for (i = 0; i < _global_klass_objects->length(); i++) { 1866 Klass* k = _global_klass_objects->at(i); 1867 1868 // archive mirror object 1869 java_lang_Class::archive_mirror(k, CHECK); 1870 1871 // archive the resolved_referenes array 1872 if (k->is_instance_klass()) { 1873 InstanceKlass* ik = InstanceKlass::cast(k); 1874 ik->constants()->archive_resolved_references(THREAD); 1875 } 1876 } 1877 } 1878 1879 void MetaspaceShared::fixup_mapped_heap_regions() { 1880 FileMapInfo *mapinfo = FileMapInfo::current_info(); 1881 mapinfo->fixup_mapped_heap_regions(); 1882 } 1883 #endif // INCLUDE_CDS_JAVA_HEAP 1884 1885 // Closure for serializing initialization data in from a data area 1886 // (ptr_array) read from the shared file. 1887 1888 class ReadClosure : public SerializeClosure { 1889 private: 1890 intptr_t** _ptr_array; 1891 1892 inline intptr_t nextPtr() { 1893 return *(*_ptr_array)++; 1894 } 1895 1896 public: 1897 ReadClosure(intptr_t** ptr_array) { _ptr_array = ptr_array; } 1898 1899 void do_ptr(void** p) { 1900 assert(*p == NULL, "initializing previous initialized pointer."); 1901 intptr_t obj = nextPtr(); 1902 assert((intptr_t)obj >= 0 || (intptr_t)obj < -100, 1903 "hit tag while initializing ptrs."); 1904 *p = (void*)obj; 1905 } 1906 1907 void do_u4(u4* p) { 1908 intptr_t obj = nextPtr(); 1909 *p = (u4)(uintx(obj)); 1910 } 1911 1912 void do_tag(int tag) { 1913 int old_tag; 1914 old_tag = (int)(intptr_t)nextPtr(); 1915 // do_int(&old_tag); 1916 assert(tag == old_tag, "old tag doesn't match"); 1917 FileMapInfo::assert_mark(tag == old_tag); 1918 } 1919 1920 void do_oop(oop *p) { 1921 narrowOop o = (narrowOop)nextPtr(); 1922 if (o == 0 || !MetaspaceShared::open_archive_heap_region_mapped()) { 1923 p = NULL; 1924 } else { 1925 assert(MetaspaceShared::is_heap_object_archiving_allowed(), 1926 "Archived heap object is not allowed"); 1927 assert(MetaspaceShared::open_archive_heap_region_mapped(), 1928 "Open archive heap region is not mapped"); 1929 RootAccess<IN_ARCHIVE_ROOT>::oop_store(p, oopDesc::decode_heap_oop_not_null(o)); 1930 } 1931 } 1932 1933 void do_region(u_char* start, size_t size) { 1934 assert((intptr_t)start % sizeof(intptr_t) == 0, "bad alignment"); 1935 assert(size % sizeof(intptr_t) == 0, "bad size"); 1936 do_tag((int)size); 1937 while (size > 0) { 1938 *(intptr_t*)start = nextPtr(); 1939 start += sizeof(intptr_t); 1940 size -= sizeof(intptr_t); 1941 } 1942 } 1943 1944 bool reading() const { return true; } 1945 }; 1946 1947 // Return true if given address is in the misc data region 1948 bool MetaspaceShared::is_in_shared_region(const void* p, int idx) { 1949 return UseSharedSpaces && FileMapInfo::current_info()->is_in_shared_region(p, idx); 1950 } 1951 1952 bool MetaspaceShared::is_in_trampoline_frame(address addr) { 1953 if (UseSharedSpaces && is_in_shared_region(addr, MetaspaceShared::mc)) { 1954 return true; 1955 } 1956 return false; 1957 } 1958 1959 void MetaspaceShared::print_shared_spaces() { 1960 if (UseSharedSpaces) { 1961 FileMapInfo::current_info()->print_shared_spaces(); 1962 } 1963 } 1964 1965 1966 // Map shared spaces at requested addresses and return if succeeded. 1967 bool MetaspaceShared::map_shared_spaces(FileMapInfo* mapinfo) { 1968 size_t image_alignment = mapinfo->alignment(); 1969 1970 #ifndef _WINDOWS 1971 // Map in the shared memory and then map the regions on top of it. 1972 // On Windows, don't map the memory here because it will cause the 1973 // mappings of the regions to fail. 1974 ReservedSpace shared_rs = mapinfo->reserve_shared_memory(); 1975 if (!shared_rs.is_reserved()) return false; 1976 #endif 1977 1978 assert(!DumpSharedSpaces, "Should not be called with DumpSharedSpaces"); 1979 1980 char* ro_base = NULL; char* ro_top; 1981 char* rw_base = NULL; char* rw_top; 1982 char* mc_base = NULL; char* mc_top; 1983 char* md_base = NULL; char* md_top; 1984 char* od_base = NULL; char* od_top; 1985 1986 // Map each shared region 1987 if ((mc_base = mapinfo->map_region(mc, &mc_top)) != NULL && 1988 (rw_base = mapinfo->map_region(rw, &rw_top)) != NULL && 1989 (ro_base = mapinfo->map_region(ro, &ro_top)) != NULL && 1990 (md_base = mapinfo->map_region(md, &md_top)) != NULL && 1991 (od_base = mapinfo->map_region(od, &od_top)) != NULL && 1992 (image_alignment == (size_t)os::vm_allocation_granularity()) && 1993 mapinfo->validate_classpath_entry_table()) { 1994 // Success -- set up MetaspaceObj::_shared_metaspace_{base,top} for 1995 // fast checking in MetaspaceShared::is_in_shared_metaspace() and 1996 // MetaspaceObj::is_shared(). 1997 // 1998 // We require that mc->rw->ro->md->od to be laid out consecutively, with no 1999 // gaps between them. That way, we can ensure that the OS won't be able to 2000 // allocate any new memory spaces inside _shared_metaspace_{base,top}, which 2001 // would mess up the simple comparision in MetaspaceShared::is_in_shared_metaspace(). 2002 assert(mc_base < ro_base && mc_base < rw_base && mc_base < md_base && mc_base < od_base, "must be"); 2003 assert(od_top > ro_top && od_top > rw_top && od_top > md_top && od_top > mc_top , "must be"); 2004 assert(mc_top == rw_base, "must be"); 2005 assert(rw_top == ro_base, "must be"); 2006 assert(ro_top == md_base, "must be"); 2007 assert(md_top == od_base, "must be"); 2008 2009 MetaspaceObj::_shared_metaspace_base = (void*)mc_base; 2010 MetaspaceObj::_shared_metaspace_top = (void*)od_top; 2011 return true; 2012 } else { 2013 // If there was a failure in mapping any of the spaces, unmap the ones 2014 // that succeeded 2015 if (ro_base != NULL) mapinfo->unmap_region(ro); 2016 if (rw_base != NULL) mapinfo->unmap_region(rw); 2017 if (mc_base != NULL) mapinfo->unmap_region(mc); 2018 if (md_base != NULL) mapinfo->unmap_region(md); 2019 if (od_base != NULL) mapinfo->unmap_region(od); 2020 #ifndef _WINDOWS 2021 // Release the entire mapped region 2022 shared_rs.release(); 2023 #endif 2024 // If -Xshare:on is specified, print out the error message and exit VM, 2025 // otherwise, set UseSharedSpaces to false and continue. 2026 if (RequireSharedSpaces || PrintSharedArchiveAndExit) { 2027 vm_exit_during_initialization("Unable to use shared archive.", "Failed map_region for using -Xshare:on."); 2028 } else { 2029 FLAG_SET_DEFAULT(UseSharedSpaces, false); 2030 } 2031 return false; 2032 } 2033 } 2034 2035 // Read the miscellaneous data from the shared file, and 2036 // serialize it out to its various destinations. 2037 2038 void MetaspaceShared::initialize_shared_spaces() { 2039 FileMapInfo *mapinfo = FileMapInfo::current_info(); 2040 _cds_i2i_entry_code_buffers = mapinfo->cds_i2i_entry_code_buffers(); 2041 _cds_i2i_entry_code_buffers_size = mapinfo->cds_i2i_entry_code_buffers_size(); 2042 _core_spaces_size = mapinfo->core_spaces_size(); 2043 char* buffer = mapinfo->misc_data_patching_start(); 2044 clone_cpp_vtables((intptr_t*)buffer); 2045 2046 // The rest of the data is now stored in the RW region 2047 buffer = mapinfo->read_only_tables_start(); 2048 int sharedDictionaryLen = *(intptr_t*)buffer; 2049 buffer += sizeof(intptr_t); 2050 int number_of_entries = *(intptr_t*)buffer; 2051 buffer += sizeof(intptr_t); 2052 SystemDictionary::set_shared_dictionary((HashtableBucket<mtClass>*)buffer, 2053 sharedDictionaryLen, 2054 number_of_entries); 2055 buffer += sharedDictionaryLen; 2056 2057 // The following data are the linked list elements 2058 // (HashtableEntry objects) for the shared dictionary table. 2059 2060 int len = *(intptr_t*)buffer; // skip over shared dictionary entries 2061 buffer += sizeof(intptr_t); 2062 buffer += len; 2063 2064 // Verify various attributes of the archive, plus initialize the 2065 // shared string/symbol tables 2066 intptr_t* array = (intptr_t*)buffer; 2067 ReadClosure rc(&array); 2068 serialize(&rc); 2069 2070 // Initialize the run-time symbol table. 2071 SymbolTable::create_table(); 2072 2073 // Close the mapinfo file 2074 mapinfo->close(); 2075 2076 if (PrintSharedArchiveAndExit) { 2077 if (PrintSharedDictionary) { 2078 tty->print_cr("\nShared classes:\n"); 2079 SystemDictionary::print_shared(tty); 2080 } 2081 if (_archive_loading_failed) { 2082 tty->print_cr("archive is invalid"); 2083 vm_exit(1); 2084 } else { 2085 tty->print_cr("archive is valid"); 2086 vm_exit(0); 2087 } 2088 } 2089 } 2090 2091 // JVM/TI RedefineClasses() support: 2092 bool MetaspaceShared::remap_shared_readonly_as_readwrite() { 2093 assert(SafepointSynchronize::is_at_safepoint(), "must be at safepoint"); 2094 2095 if (UseSharedSpaces) { 2096 // remap the shared readonly space to shared readwrite, private 2097 FileMapInfo* mapinfo = FileMapInfo::current_info(); 2098 if (!mapinfo->remap_shared_readonly_as_readwrite()) { 2099 return false; 2100 } 2101 _remapped_readwrite = true; 2102 } 2103 return true; 2104 } 2105 2106 void MetaspaceShared::report_out_of_space(const char* name, size_t needed_bytes) { 2107 // This is highly unlikely to happen on 64-bits because we have reserved a 4GB space. 2108 // On 32-bit we reserve only 256MB so you could run out of space with 100,000 classes 2109 // or so. 2110 _mc_region.print_out_of_space_msg(name, needed_bytes); 2111 _rw_region.print_out_of_space_msg(name, needed_bytes); 2112 _ro_region.print_out_of_space_msg(name, needed_bytes); 2113 _md_region.print_out_of_space_msg(name, needed_bytes); 2114 _od_region.print_out_of_space_msg(name, needed_bytes); 2115 2116 vm_exit_during_initialization(err_msg("Unable to allocate from '%s' region", name), 2117 "Please reduce the number of shared classes."); 2118 }