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/symbolTable.hpp" 33 #include "classfile/stringTable.hpp" 34 #include "classfile/systemDictionary.hpp" 35 #include "classfile/systemDictionaryShared.hpp" 36 #include "code/codeCache.hpp" 37 #include "interpreter/bytecodeStream.hpp" 38 #include "interpreter/bytecodes.hpp" 39 #include "logging/log.hpp" 40 #include "logging/logMessage.hpp" 41 #include "memory/filemap.hpp" 42 #include "memory/heapShared.inline.hpp" 43 #include "memory/metaspace.hpp" 44 #include "memory/metaspaceClosure.hpp" 45 #include "memory/metaspaceShared.hpp" 46 #include "memory/resourceArea.hpp" 47 #include "oops/compressedOops.inline.hpp" 48 #include "oops/instanceClassLoaderKlass.hpp" 49 #include "oops/instanceMirrorKlass.hpp" 50 #include "oops/instanceRefKlass.hpp" 51 #include "oops/objArrayKlass.hpp" 52 #include "oops/objArrayOop.hpp" 53 #include "oops/oop.inline.hpp" 54 #include "oops/typeArrayKlass.hpp" 55 #include "prims/jvmtiRedefineClasses.hpp" 56 #include "runtime/handles.inline.hpp" 57 #include "runtime/os.hpp" 58 #include "runtime/safepointVerifiers.hpp" 59 #include "runtime/signature.hpp" 60 #include "runtime/timerTrace.hpp" 61 #include "runtime/vmThread.hpp" 62 #include "runtime/vmOperations.hpp" 63 #include "utilities/align.hpp" 64 #include "utilities/bitMap.hpp" 65 #include "utilities/defaultStream.hpp" 66 #include "utilities/hashtable.inline.hpp" 67 #if INCLUDE_G1GC 68 #include "gc/g1/g1Allocator.inline.hpp" 69 #include "gc/g1/g1CollectedHeap.hpp" 70 #endif 71 72 ReservedSpace MetaspaceShared::_shared_rs; 73 VirtualSpace MetaspaceShared::_shared_vs; 74 MetaspaceSharedStats MetaspaceShared::_stats; 75 bool MetaspaceShared::_has_error_classes; 76 bool MetaspaceShared::_archive_loading_failed = false; 77 bool MetaspaceShared::_remapped_readwrite = false; 78 bool MetaspaceShared::_open_archive_heap_region_mapped = false; 79 address MetaspaceShared::_cds_i2i_entry_code_buffers = NULL; 80 size_t MetaspaceShared::_cds_i2i_entry_code_buffers_size = 0; 81 size_t MetaspaceShared::_core_spaces_size = 0; 82 83 // The CDS archive is divided into the following regions: 84 // mc - misc code (the method entry trampolines) 85 // rw - read-write metadata 86 // ro - read-only metadata and read-only tables 87 // md - misc data (the c++ vtables) 88 // od - optional data (original class files) 89 // 90 // s0 - shared strings(closed archive heap space) #0 91 // s1 - shared strings(closed archive heap space) #1 (may be empty) 92 // oa0 - open archive heap space #0 93 // oa1 - open archive heap space #1 (may be empty) 94 // 95 // The mc, rw, ro, md and od regions are linearly allocated, starting from 96 // SharedBaseAddress, in the order of mc->rw->ro->md->od. The size of these 5 regions 97 // are page-aligned, and there's no gap between any consecutive regions. 98 // 99 // These 5 regions are populated in the following steps: 100 // [1] All classes are loaded in MetaspaceShared::preload_classes(). All metadata are 101 // temporarily allocated outside of the shared regions. Only the method entry 102 // trampolines are written into the mc region. 103 // [2] ArchiveCompactor copies RW metadata into the rw region. 104 // [3] ArchiveCompactor copies RO metadata into the ro region. 105 // [4] SymbolTable, StringTable, SystemDictionary, and a few other read-only data 106 // are copied into the ro region as read-only tables. 107 // [5] C++ vtables are copied into the md region. 108 // [6] Original class files are copied into the od region. 109 // 110 // The s0/s1 and oa0/oa1 regions are populated inside MetaspaceShared::dump_java_heap_objects. 111 // Their layout is independent of the other 5 regions. 112 113 class DumpRegion { 114 private: 115 const char* _name; 116 char* _base; 117 char* _top; 118 char* _end; 119 bool _is_packed; 120 121 char* expand_top_to(char* newtop) { 122 assert(is_allocatable(), "must be initialized and not packed"); 123 assert(newtop >= _top, "must not grow backwards"); 124 if (newtop > _end) { 125 MetaspaceShared::report_out_of_space(_name, newtop - _top); 126 ShouldNotReachHere(); 127 } 128 MetaspaceShared::commit_shared_space_to(newtop); 129 _top = newtop; 130 return _top; 131 } 132 133 public: 134 DumpRegion(const char* name) : _name(name), _base(NULL), _top(NULL), _end(NULL), _is_packed(false) {} 135 136 char* allocate(size_t num_bytes, size_t alignment=BytesPerWord) { 137 char* p = (char*)align_up(_top, alignment); 138 char* newtop = p + align_up(num_bytes, alignment); 139 expand_top_to(newtop); 140 memset(p, 0, newtop - p); 141 return p; 142 } 143 144 void append_intptr_t(intptr_t n) { 145 assert(is_aligned(_top, sizeof(intptr_t)), "bad alignment"); 146 intptr_t *p = (intptr_t*)_top; 147 char* newtop = _top + sizeof(intptr_t); 148 expand_top_to(newtop); 149 *p = n; 150 } 151 152 char* base() const { return _base; } 153 char* top() const { return _top; } 154 char* end() const { return _end; } 155 size_t reserved() const { return _end - _base; } 156 size_t used() const { return _top - _base; } 157 bool is_packed() const { return _is_packed; } 158 bool is_allocatable() const { 159 return !is_packed() && _base != NULL; 160 } 161 162 void print(size_t total_bytes) const { 163 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, 164 _name, used(), percent_of(used(), total_bytes), reserved(), percent_of(used(), reserved()), p2i(_base)); 165 } 166 void print_out_of_space_msg(const char* failing_region, size_t needed_bytes) { 167 tty->print("[%-8s] " PTR_FORMAT " - " PTR_FORMAT " capacity =%9d, allocated =%9d", 168 _name, p2i(_base), p2i(_top), int(_end - _base), int(_top - _base)); 169 if (strcmp(_name, failing_region) == 0) { 170 tty->print_cr(" required = %d", int(needed_bytes)); 171 } else { 172 tty->cr(); 173 } 174 } 175 176 void init(const ReservedSpace* rs) { 177 _base = _top = rs->base(); 178 _end = rs->end(); 179 } 180 void init(char* b, char* t, char* e) { 181 _base = b; 182 _top = t; 183 _end = e; 184 } 185 186 void pack(DumpRegion* next = NULL) { 187 assert(!is_packed(), "sanity"); 188 _end = (char*)align_up(_top, Metaspace::reserve_alignment()); 189 _is_packed = true; 190 if (next != NULL) { 191 next->_base = next->_top = this->_end; 192 next->_end = MetaspaceShared::shared_rs()->end(); 193 } 194 } 195 bool contains(char* p) { 196 return base() <= p && p < top(); 197 } 198 }; 199 200 201 DumpRegion _mc_region("mc"), _ro_region("ro"), _rw_region("rw"), _md_region("md"), _od_region("od"); 202 size_t _total_string_region_size = 0, _total_open_archive_region_size = 0; 203 204 char* MetaspaceShared::misc_code_space_alloc(size_t num_bytes) { 205 return _mc_region.allocate(num_bytes); 206 } 207 208 char* MetaspaceShared::read_only_space_alloc(size_t num_bytes) { 209 return _ro_region.allocate(num_bytes); 210 } 211 212 char* MetaspaceShared::read_only_space_top() { 213 return _ro_region.top(); 214 } 215 216 void MetaspaceShared::initialize_runtime_shared_and_meta_spaces() { 217 assert(UseSharedSpaces, "Must be called when UseSharedSpaces is enabled"); 218 219 // If using shared space, open the file that contains the shared space 220 // and map in the memory before initializing the rest of metaspace (so 221 // the addresses don't conflict) 222 address cds_address = NULL; 223 FileMapInfo* mapinfo = new FileMapInfo(); 224 225 // Open the shared archive file, read and validate the header. If 226 // initialization fails, shared spaces [UseSharedSpaces] are 227 // disabled and the file is closed. 228 // Map in spaces now also 229 if (mapinfo->initialize() && map_shared_spaces(mapinfo)) { 230 size_t cds_total = core_spaces_size(); 231 cds_address = (address)mapinfo->region_addr(0); 232 #ifdef _LP64 233 if (Metaspace::using_class_space()) { 234 char* cds_end = (char*)(cds_address + cds_total); 235 cds_end = (char *)align_up(cds_end, Metaspace::reserve_alignment()); 236 // If UseCompressedClassPointers is set then allocate the metaspace area 237 // above the heap and above the CDS area (if it exists). 238 Metaspace::allocate_metaspace_compressed_klass_ptrs(cds_end, cds_address); 239 // map_heap_regions() compares the current narrow oop and klass encodings 240 // with the archived ones, so it must be done after all encodings are determined. 241 mapinfo->map_heap_regions(); 242 } 243 Universe::set_narrow_klass_range(CompressedClassSpaceSize); 244 #endif // _LP64 245 } else { 246 assert(!mapinfo->is_open() && !UseSharedSpaces, 247 "archive file not closed or shared spaces not disabled."); 248 } 249 } 250 251 void MetaspaceShared::initialize_dumptime_shared_and_meta_spaces() { 252 assert(DumpSharedSpaces, "should be called for dump time only"); 253 const size_t reserve_alignment = Metaspace::reserve_alignment(); 254 bool large_pages = false; // No large pages when dumping the CDS archive. 255 char* shared_base = (char*)align_up((char*)SharedBaseAddress, reserve_alignment); 256 257 #ifdef _LP64 258 // On 64-bit VM, the heap and class space layout will be the same as if 259 // you're running in -Xshare:on mode: 260 // 261 // +-- SharedBaseAddress (default = 0x800000000) 262 // v 263 // +-..---------+---------+ ... +----+----+----+----+----+---------------+ 264 // | Heap | Archive | | MC | RW | RO | MD | OD | class space | 265 // +-..---------+---------+ ... +----+----+----+----+----+---------------+ 266 // |<-- MaxHeapSize -->| |<-- UnscaledClassSpaceMax = 4GB ------->| 267 // 268 const uint64_t UnscaledClassSpaceMax = (uint64_t(max_juint) + 1); 269 const size_t cds_total = align_down(UnscaledClassSpaceMax, reserve_alignment); 270 #else 271 // We don't support archives larger than 256MB on 32-bit due to limited virtual address space. 272 size_t cds_total = align_down(256*M, reserve_alignment); 273 #endif 274 275 // First try to reserve the space at the specified SharedBaseAddress. 276 _shared_rs = ReservedSpace(cds_total, reserve_alignment, large_pages, shared_base); 277 if (_shared_rs.is_reserved()) { 278 assert(shared_base == 0 || _shared_rs.base() == shared_base, "should match"); 279 } else { 280 // Get a mmap region anywhere if the SharedBaseAddress fails. 281 _shared_rs = ReservedSpace(cds_total, reserve_alignment, large_pages); 282 } 283 if (!_shared_rs.is_reserved()) { 284 vm_exit_during_initialization("Unable to reserve memory for shared space", 285 err_msg(SIZE_FORMAT " bytes.", cds_total)); 286 } 287 288 #ifdef _LP64 289 // During dump time, we allocate 4GB (UnscaledClassSpaceMax) of space and split it up: 290 // + The upper 1 GB is used as the "temporary compressed class space" -- preload_classes() 291 // will store Klasses into this space. 292 // + The lower 3 GB is used for the archive -- when preload_classes() is done, 293 // ArchiveCompactor will copy the class metadata into this space, first the RW parts, 294 // then the RO parts. 295 296 assert(UseCompressedOops && UseCompressedClassPointers, 297 "UseCompressedOops and UseCompressedClassPointers must be set"); 298 299 size_t max_archive_size = align_down(cds_total * 3 / 4, reserve_alignment); 300 ReservedSpace tmp_class_space = _shared_rs.last_part(max_archive_size); 301 CompressedClassSpaceSize = align_down(tmp_class_space.size(), reserve_alignment); 302 _shared_rs = _shared_rs.first_part(max_archive_size); 303 304 // Set up compress class pointers. 305 Universe::set_narrow_klass_base((address)_shared_rs.base()); 306 // Set narrow_klass_shift to be LogKlassAlignmentInBytes. This is consistent 307 // with AOT. 308 Universe::set_narrow_klass_shift(LogKlassAlignmentInBytes); 309 // Set the range of klass addresses to 4GB. 310 Universe::set_narrow_klass_range(cds_total); 311 312 Metaspace::initialize_class_space(tmp_class_space); 313 log_info(cds)("narrow_klass_base = " PTR_FORMAT ", narrow_klass_shift = %d", 314 p2i(Universe::narrow_klass_base()), Universe::narrow_klass_shift()); 315 316 log_info(cds)("Allocated temporary class space: " SIZE_FORMAT " bytes at " PTR_FORMAT, 317 CompressedClassSpaceSize, p2i(tmp_class_space.base())); 318 #endif 319 320 // Start with 0 committed bytes. The memory will be committed as needed by 321 // MetaspaceShared::commit_shared_space_to(). 322 if (!_shared_vs.initialize(_shared_rs, 0)) { 323 vm_exit_during_initialization("Unable to allocate memory for shared space"); 324 } 325 326 _mc_region.init(&_shared_rs); 327 tty->print_cr("Allocated shared space: " SIZE_FORMAT " bytes at " PTR_FORMAT, 328 _shared_rs.size(), p2i(_shared_rs.base())); 329 } 330 331 // Called by universe_post_init() 332 void MetaspaceShared::post_initialize(TRAPS) { 333 if (UseSharedSpaces) { 334 int size = FileMapInfo::get_number_of_shared_paths(); 335 if (size > 0) { 336 SystemDictionaryShared::allocate_shared_data_arrays(size, THREAD); 337 FileMapHeader* header = FileMapInfo::current_info()->header(); 338 ClassLoaderExt::init_paths_start_index(header->_app_class_paths_start_index); 339 ClassLoaderExt::init_app_module_paths_start_index(header->_app_module_paths_start_index); 340 } 341 } 342 343 if (DumpSharedSpaces) { 344 if (SharedArchiveConfigFile) { 345 read_extra_data(SharedArchiveConfigFile, THREAD); 346 } 347 } 348 } 349 350 void MetaspaceShared::read_extra_data(const char* filename, TRAPS) { 351 HashtableTextDump reader(filename); 352 reader.check_version("VERSION: 1.0"); 353 354 while (reader.remain() > 0) { 355 int utf8_length; 356 int prefix_type = reader.scan_prefix(&utf8_length); 357 ResourceMark rm(THREAD); 358 char* utf8_buffer = NEW_RESOURCE_ARRAY(char, utf8_length); 359 reader.get_utf8(utf8_buffer, utf8_length); 360 361 if (prefix_type == HashtableTextDump::SymbolPrefix) { 362 SymbolTable::new_symbol(utf8_buffer, utf8_length, THREAD); 363 } else{ 364 assert(prefix_type == HashtableTextDump::StringPrefix, "Sanity"); 365 utf8_buffer[utf8_length] = '\0'; 366 oop s = StringTable::intern(utf8_buffer, THREAD); 367 } 368 } 369 } 370 371 void MetaspaceShared::commit_shared_space_to(char* newtop) { 372 assert(DumpSharedSpaces, "dump-time only"); 373 char* base = _shared_rs.base(); 374 size_t need_committed_size = newtop - base; 375 size_t has_committed_size = _shared_vs.committed_size(); 376 if (need_committed_size < has_committed_size) { 377 return; 378 } 379 380 size_t min_bytes = need_committed_size - has_committed_size; 381 size_t preferred_bytes = 1 * M; 382 size_t uncommitted = _shared_vs.reserved_size() - has_committed_size; 383 384 size_t commit = MAX2(min_bytes, preferred_bytes); 385 assert(commit <= uncommitted, "sanity"); 386 387 bool result = _shared_vs.expand_by(commit, false); 388 if (!result) { 389 vm_exit_during_initialization(err_msg("Failed to expand shared space to " SIZE_FORMAT " bytes", 390 need_committed_size)); 391 } 392 393 log_info(cds)("Expanding shared spaces by " SIZE_FORMAT_W(7) " bytes [total " SIZE_FORMAT_W(9) " bytes ending at %p]", 394 commit, _shared_vs.actual_committed_size(), _shared_vs.high()); 395 } 396 397 // Read/write a data stream for restoring/preserving metadata pointers and 398 // miscellaneous data from/to the shared archive file. 399 400 void MetaspaceShared::serialize(SerializeClosure* soc) { 401 int tag = 0; 402 soc->do_tag(--tag); 403 404 // Verify the sizes of various metadata in the system. 405 soc->do_tag(sizeof(Method)); 406 soc->do_tag(sizeof(ConstMethod)); 407 soc->do_tag(arrayOopDesc::base_offset_in_bytes(T_BYTE)); 408 soc->do_tag(sizeof(ConstantPool)); 409 soc->do_tag(sizeof(ConstantPoolCache)); 410 soc->do_tag(objArrayOopDesc::base_offset_in_bytes()); 411 soc->do_tag(typeArrayOopDesc::base_offset_in_bytes(T_BYTE)); 412 soc->do_tag(sizeof(Symbol)); 413 414 // Dump/restore miscellaneous metadata. 415 Universe::serialize(soc, true); 416 soc->do_tag(--tag); 417 418 // Dump/restore references to commonly used names and signatures. 419 vmSymbols::serialize(soc); 420 soc->do_tag(--tag); 421 422 // Dump/restore the symbol and string tables 423 SymbolTable::serialize(soc); 424 StringTable::serialize(soc); 425 soc->do_tag(--tag); 426 427 JavaClasses::serialize_offsets(soc); 428 InstanceMirrorKlass::serialize_offsets(soc); 429 soc->do_tag(--tag); 430 431 soc->do_tag(666); 432 } 433 434 address MetaspaceShared::cds_i2i_entry_code_buffers(size_t total_size) { 435 if (DumpSharedSpaces) { 436 if (_cds_i2i_entry_code_buffers == NULL) { 437 _cds_i2i_entry_code_buffers = (address)misc_code_space_alloc(total_size); 438 _cds_i2i_entry_code_buffers_size = total_size; 439 } 440 } else if (UseSharedSpaces) { 441 assert(_cds_i2i_entry_code_buffers != NULL, "must already been initialized"); 442 } else { 443 return NULL; 444 } 445 446 assert(_cds_i2i_entry_code_buffers_size == total_size, "must not change"); 447 return _cds_i2i_entry_code_buffers; 448 } 449 450 // CDS code for dumping shared archive. 451 452 // Global object for holding classes that have been loaded. Since this 453 // is run at a safepoint just before exit, this is the entire set of classes. 454 static GrowableArray<Klass*>* _global_klass_objects; 455 456 static void collect_array_classes(Klass* k) { 457 _global_klass_objects->append_if_missing(k); 458 if (k->is_array_klass()) { 459 // Add in the array classes too 460 ArrayKlass* ak = ArrayKlass::cast(k); 461 Klass* h = ak->higher_dimension(); 462 if (h != NULL) { 463 h->array_klasses_do(collect_array_classes); 464 } 465 } 466 } 467 468 class CollectClassesClosure : public KlassClosure { 469 void do_klass(Klass* k) { 470 if (!(k->is_instance_klass() && InstanceKlass::cast(k)->is_in_error_state())) { 471 if (k->is_instance_klass() && InstanceKlass::cast(k)->signers() != NULL) { 472 // Mark any class with signers and don't add to the _global_klass_objects 473 k->set_has_signer_and_not_archived(); 474 } else { 475 _global_klass_objects->append_if_missing(k); 476 } 477 } 478 if (k->is_array_klass()) { 479 // Add in the array classes too 480 ArrayKlass* ak = ArrayKlass::cast(k); 481 Klass* h = ak->higher_dimension(); 482 if (h != NULL) { 483 h->array_klasses_do(collect_array_classes); 484 } 485 } 486 } 487 }; 488 489 static void remove_unshareable_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_unshareable_info(); 497 } 498 } 499 } 500 501 static void remove_java_mirror_in_classes() { 502 for (int i = 0; i < _global_klass_objects->length(); i++) { 503 Klass* k = _global_klass_objects->at(i); 504 if (!k->is_objArray_klass()) { 505 // InstanceKlass and TypeArrayKlass will in turn call remove_unshareable_info 506 // on their array classes. 507 assert(k->is_instance_klass() || k->is_typeArray_klass(), "must be"); 508 k->remove_java_mirror(); 509 } 510 } 511 } 512 513 static void clear_basic_type_mirrors() { 514 assert(!MetaspaceShared::is_heap_object_archiving_allowed(), "Sanity"); 515 Universe::set_int_mirror(NULL); 516 Universe::set_float_mirror(NULL); 517 Universe::set_double_mirror(NULL); 518 Universe::set_byte_mirror(NULL); 519 Universe::set_bool_mirror(NULL); 520 Universe::set_char_mirror(NULL); 521 Universe::set_long_mirror(NULL); 522 Universe::set_short_mirror(NULL); 523 Universe::set_void_mirror(NULL); 524 } 525 526 static void rewrite_nofast_bytecode(Method* method) { 527 BytecodeStream bcs(method); 528 while (!bcs.is_last_bytecode()) { 529 Bytecodes::Code opcode = bcs.next(); 530 switch (opcode) { 531 case Bytecodes::_getfield: *bcs.bcp() = Bytecodes::_nofast_getfield; break; 532 case Bytecodes::_putfield: *bcs.bcp() = Bytecodes::_nofast_putfield; break; 533 case Bytecodes::_aload_0: *bcs.bcp() = Bytecodes::_nofast_aload_0; break; 534 case Bytecodes::_iload: { 535 if (!bcs.is_wide()) { 536 *bcs.bcp() = Bytecodes::_nofast_iload; 537 } 538 break; 539 } 540 default: break; 541 } 542 } 543 } 544 545 // Walk all methods in the class list to ensure that they won't be modified at 546 // run time. This includes: 547 // [1] Rewrite all bytecodes as needed, so that the ConstMethod* will not be modified 548 // at run time by RewriteBytecodes/RewriteFrequentPairs 549 // [2] Assign a fingerprint, so one doesn't need to be assigned at run-time. 550 static void rewrite_nofast_bytecodes_and_calculate_fingerprints() { 551 for (int i = 0; i < _global_klass_objects->length(); i++) { 552 Klass* k = _global_klass_objects->at(i); 553 if (k->is_instance_klass()) { 554 InstanceKlass* ik = InstanceKlass::cast(k); 555 for (int i = 0; i < ik->methods()->length(); i++) { 556 Method* m = ik->methods()->at(i); 557 rewrite_nofast_bytecode(m); 558 Fingerprinter fp(m); 559 // The side effect of this call sets method's fingerprint field. 560 fp.fingerprint(); 561 } 562 } 563 } 564 } 565 566 static void relocate_cached_class_file() { 567 for (int i = 0; i < _global_klass_objects->length(); i++) { 568 Klass* k = _global_klass_objects->at(i); 569 if (k->is_instance_klass()) { 570 InstanceKlass* ik = InstanceKlass::cast(k); 571 JvmtiCachedClassFileData* p = ik->get_archived_class_data(); 572 if (p != NULL) { 573 int size = offset_of(JvmtiCachedClassFileData, data) + p->length; 574 JvmtiCachedClassFileData* q = (JvmtiCachedClassFileData*)_od_region.allocate(size); 575 q->length = p->length; 576 memcpy(q->data, p->data, p->length); 577 ik->set_archived_class_data(q); 578 } 579 } 580 } 581 } 582 583 NOT_PRODUCT( 584 static void assert_not_anonymous_class(InstanceKlass* k) { 585 assert(!(k->is_anonymous()), "cannot archive anonymous classes"); 586 } 587 588 // Anonymous classes are not stored inside any dictionaries. They are created by 589 // SystemDictionary::parse_stream() with a non-null host_klass. 590 static void assert_no_anonymoys_classes_in_dictionaries() { 591 ClassLoaderDataGraph::dictionary_classes_do(assert_not_anonymous_class); 592 }) 593 594 // Objects of the Metadata types (such as Klass and ConstantPool) have C++ vtables. 595 // (In GCC this is the field <Type>::_vptr, i.e., first word in the object.) 596 // 597 // Addresses of the vtables and the methods may be different across JVM runs, 598 // if libjvm.so is dynamically loaded at a different base address. 599 // 600 // To ensure that the Metadata objects in the CDS archive always have the correct vtable: 601 // 602 // + at dump time: we redirect the _vptr to point to our own vtables inside 603 // the CDS image 604 // + at run time: we clone the actual contents of the vtables from libjvm.so 605 // into our own tables. 606 607 // Currently, the archive contain ONLY the following types of objects that have C++ vtables. 608 #define CPP_VTABLE_PATCH_TYPES_DO(f) \ 609 f(ConstantPool) \ 610 f(InstanceKlass) \ 611 f(InstanceClassLoaderKlass) \ 612 f(InstanceMirrorKlass) \ 613 f(InstanceRefKlass) \ 614 f(Method) \ 615 f(ObjArrayKlass) \ 616 f(TypeArrayKlass) 617 618 class CppVtableInfo { 619 intptr_t _vtable_size; 620 intptr_t _cloned_vtable[1]; 621 public: 622 static int num_slots(int vtable_size) { 623 return 1 + vtable_size; // Need to add the space occupied by _vtable_size; 624 } 625 int vtable_size() { return int(uintx(_vtable_size)); } 626 void set_vtable_size(int n) { _vtable_size = intptr_t(n); } 627 intptr_t* cloned_vtable() { return &_cloned_vtable[0]; } 628 void zero() { memset(_cloned_vtable, 0, sizeof(intptr_t) * vtable_size()); } 629 // Returns the address of the next CppVtableInfo that can be placed immediately after this CppVtableInfo 630 static size_t byte_size(int vtable_size) { 631 CppVtableInfo i; 632 return pointer_delta(&i._cloned_vtable[vtable_size], &i, sizeof(u1)); 633 } 634 }; 635 636 template <class T> class CppVtableCloner : public T { 637 static intptr_t* vtable_of(Metadata& m) { 638 return *((intptr_t**)&m); 639 } 640 static CppVtableInfo* _info; 641 642 static int get_vtable_length(const char* name); 643 644 public: 645 // Allocate and initialize the C++ vtable, starting from top, but do not go past end. 646 static intptr_t* allocate(const char* name); 647 648 // Clone the vtable to ... 649 static intptr_t* clone_vtable(const char* name, CppVtableInfo* info); 650 651 static void zero_vtable_clone() { 652 assert(DumpSharedSpaces, "dump-time only"); 653 _info->zero(); 654 } 655 656 // Switch the vtable pointer to point to the cloned vtable. 657 static void patch(Metadata* obj) { 658 assert(DumpSharedSpaces, "dump-time only"); 659 *(void**)obj = (void*)(_info->cloned_vtable()); 660 } 661 662 static bool is_valid_shared_object(const T* obj) { 663 intptr_t* vptr = *(intptr_t**)obj; 664 return vptr == _info->cloned_vtable(); 665 } 666 }; 667 668 template <class T> CppVtableInfo* CppVtableCloner<T>::_info = NULL; 669 670 template <class T> 671 intptr_t* CppVtableCloner<T>::allocate(const char* name) { 672 assert(is_aligned(_md_region.top(), sizeof(intptr_t)), "bad alignment"); 673 int n = get_vtable_length(name); 674 _info = (CppVtableInfo*)_md_region.allocate(CppVtableInfo::byte_size(n), sizeof(intptr_t)); 675 _info->set_vtable_size(n); 676 677 intptr_t* p = clone_vtable(name, _info); 678 assert((char*)p == _md_region.top(), "must be"); 679 680 return p; 681 } 682 683 template <class T> 684 intptr_t* CppVtableCloner<T>::clone_vtable(const char* name, CppVtableInfo* info) { 685 if (!DumpSharedSpaces) { 686 assert(_info == 0, "_info is initialized only at dump time"); 687 _info = info; // Remember it -- it will be used by MetaspaceShared::is_valid_shared_method() 688 } 689 T tmp; // Allocate temporary dummy metadata object to get to the original vtable. 690 int n = info->vtable_size(); 691 intptr_t* srcvtable = vtable_of(tmp); 692 intptr_t* dstvtable = info->cloned_vtable(); 693 694 // We already checked (and, if necessary, adjusted n) when the vtables were allocated, so we are 695 // safe to do memcpy. 696 log_debug(cds, vtables)("Copying %3d vtable entries for %s", n, name); 697 memcpy(dstvtable, srcvtable, sizeof(intptr_t) * n); 698 return dstvtable + n; 699 } 700 701 // To determine the size of the vtable for each type, we use the following 702 // trick by declaring 2 subclasses: 703 // 704 // class CppVtableTesterA: public InstanceKlass {virtual int last_virtual_method() {return 1;} }; 705 // class CppVtableTesterB: public InstanceKlass {virtual void* last_virtual_method() {return NULL}; }; 706 // 707 // CppVtableTesterA and CppVtableTesterB's vtables have the following properties: 708 // - Their size (N+1) is exactly one more than the size of InstanceKlass's vtable (N) 709 // - The first N entries have are exactly the same as in InstanceKlass's vtable. 710 // - Their last entry is different. 711 // 712 // So to determine the value of N, we just walk CppVtableTesterA and CppVtableTesterB's tables 713 // and find the first entry that's different. 714 // 715 // This works on all C++ compilers supported by Oracle, but you may need to tweak it for more 716 // esoteric compilers. 717 718 template <class T> class CppVtableTesterB: public T { 719 public: 720 virtual int last_virtual_method() {return 1;} 721 }; 722 723 template <class T> class CppVtableTesterA : public T { 724 public: 725 virtual void* last_virtual_method() { 726 // Make this different than CppVtableTesterB::last_virtual_method so the C++ 727 // compiler/linker won't alias the two functions. 728 return NULL; 729 } 730 }; 731 732 template <class T> 733 int CppVtableCloner<T>::get_vtable_length(const char* name) { 734 CppVtableTesterA<T> a; 735 CppVtableTesterB<T> b; 736 737 intptr_t* avtable = vtable_of(a); 738 intptr_t* bvtable = vtable_of(b); 739 740 // Start at slot 1, because slot 0 may be RTTI (on Solaris/Sparc) 741 int vtable_len = 1; 742 for (; ; vtable_len++) { 743 if (avtable[vtable_len] != bvtable[vtable_len]) { 744 break; 745 } 746 } 747 log_debug(cds, vtables)("Found %3d vtable entries for %s", vtable_len, name); 748 749 return vtable_len; 750 } 751 752 #define ALLOC_CPP_VTABLE_CLONE(c) \ 753 CppVtableCloner<c>::allocate(#c); 754 755 #define CLONE_CPP_VTABLE(c) \ 756 p = CppVtableCloner<c>::clone_vtable(#c, (CppVtableInfo*)p); 757 758 #define ZERO_CPP_VTABLE(c) \ 759 CppVtableCloner<c>::zero_vtable_clone(); 760 761 // This can be called at both dump time and run time. 762 intptr_t* MetaspaceShared::clone_cpp_vtables(intptr_t* p) { 763 assert(DumpSharedSpaces || UseSharedSpaces, "sanity"); 764 CPP_VTABLE_PATCH_TYPES_DO(CLONE_CPP_VTABLE); 765 return p; 766 } 767 768 void MetaspaceShared::zero_cpp_vtable_clones_for_writing() { 769 assert(DumpSharedSpaces, "dump-time only"); 770 CPP_VTABLE_PATCH_TYPES_DO(ZERO_CPP_VTABLE); 771 } 772 773 // Allocate and initialize the C++ vtables, starting from top, but do not go past end. 774 void MetaspaceShared::allocate_cpp_vtable_clones() { 775 assert(DumpSharedSpaces, "dump-time only"); 776 // Layout (each slot is a intptr_t): 777 // [number of slots in the first vtable = n1] 778 // [ <n1> slots for the first vtable] 779 // [number of slots in the first second = n2] 780 // [ <n2> slots for the second vtable] 781 // ... 782 // The order of the vtables is the same as the CPP_VTAB_PATCH_TYPES_DO macro. 783 CPP_VTABLE_PATCH_TYPES_DO(ALLOC_CPP_VTABLE_CLONE); 784 } 785 786 // Switch the vtable pointer to point to the cloned vtable. We assume the 787 // vtable pointer is in first slot in object. 788 void MetaspaceShared::patch_cpp_vtable_pointers() { 789 int n = _global_klass_objects->length(); 790 for (int i = 0; i < n; i++) { 791 Klass* obj = _global_klass_objects->at(i); 792 if (obj->is_instance_klass()) { 793 InstanceKlass* ik = InstanceKlass::cast(obj); 794 if (ik->is_class_loader_instance_klass()) { 795 CppVtableCloner<InstanceClassLoaderKlass>::patch(ik); 796 } else if (ik->is_reference_instance_klass()) { 797 CppVtableCloner<InstanceRefKlass>::patch(ik); 798 } else if (ik->is_mirror_instance_klass()) { 799 CppVtableCloner<InstanceMirrorKlass>::patch(ik); 800 } else { 801 CppVtableCloner<InstanceKlass>::patch(ik); 802 } 803 ConstantPool* cp = ik->constants(); 804 CppVtableCloner<ConstantPool>::patch(cp); 805 for (int j = 0; j < ik->methods()->length(); j++) { 806 Method* m = ik->methods()->at(j); 807 CppVtableCloner<Method>::patch(m); 808 assert(CppVtableCloner<Method>::is_valid_shared_object(m), "must be"); 809 } 810 } else if (obj->is_objArray_klass()) { 811 CppVtableCloner<ObjArrayKlass>::patch(obj); 812 } else { 813 assert(obj->is_typeArray_klass(), "sanity"); 814 CppVtableCloner<TypeArrayKlass>::patch(obj); 815 } 816 } 817 } 818 819 bool MetaspaceShared::is_valid_shared_method(const Method* m) { 820 assert(is_in_shared_metaspace(m), "must be"); 821 return CppVtableCloner<Method>::is_valid_shared_object(m); 822 } 823 824 // Closure for serializing initialization data out to a data area to be 825 // written to the shared file. 826 827 class WriteClosure : public SerializeClosure { 828 private: 829 DumpRegion* _dump_region; 830 831 public: 832 WriteClosure(DumpRegion* r) { 833 _dump_region = r; 834 } 835 836 void do_ptr(void** p) { 837 _dump_region->append_intptr_t((intptr_t)*p); 838 } 839 840 void do_u4(u4* p) { 841 void* ptr = (void*)(uintx(*p)); 842 do_ptr(&ptr); 843 } 844 845 void do_tag(int tag) { 846 _dump_region->append_intptr_t((intptr_t)tag); 847 } 848 849 void do_oop(oop* o) { 850 if (*o == NULL) { 851 _dump_region->append_intptr_t(0); 852 } else { 853 assert(MetaspaceShared::is_heap_object_archiving_allowed(), 854 "Archiving heap object is not allowed"); 855 _dump_region->append_intptr_t( 856 (intptr_t)CompressedOops::encode_not_null(*o)); 857 } 858 } 859 860 void do_region(u_char* start, size_t size) { 861 assert((intptr_t)start % sizeof(intptr_t) == 0, "bad alignment"); 862 assert(size % sizeof(intptr_t) == 0, "bad size"); 863 do_tag((int)size); 864 while (size > 0) { 865 _dump_region->append_intptr_t(*(intptr_t*)start); 866 start += sizeof(intptr_t); 867 size -= sizeof(intptr_t); 868 } 869 } 870 871 bool reading() const { return false; } 872 }; 873 874 // This is for dumping detailed statistics for the allocations 875 // in the shared spaces. 876 class DumpAllocStats : public ResourceObj { 877 public: 878 879 // Here's poor man's enum inheritance 880 #define SHAREDSPACE_OBJ_TYPES_DO(f) \ 881 METASPACE_OBJ_TYPES_DO(f) \ 882 f(SymbolHashentry) \ 883 f(SymbolBucket) \ 884 f(StringHashentry) \ 885 f(StringBucket) \ 886 f(Other) 887 888 enum Type { 889 // Types are MetaspaceObj::ClassType, MetaspaceObj::SymbolType, etc 890 SHAREDSPACE_OBJ_TYPES_DO(METASPACE_OBJ_TYPE_DECLARE) 891 _number_of_types 892 }; 893 894 static const char * type_name(Type type) { 895 switch(type) { 896 SHAREDSPACE_OBJ_TYPES_DO(METASPACE_OBJ_TYPE_NAME_CASE) 897 default: 898 ShouldNotReachHere(); 899 return NULL; 900 } 901 } 902 903 public: 904 enum { RO = 0, RW = 1 }; 905 906 int _counts[2][_number_of_types]; 907 int _bytes [2][_number_of_types]; 908 909 DumpAllocStats() { 910 memset(_counts, 0, sizeof(_counts)); 911 memset(_bytes, 0, sizeof(_bytes)); 912 }; 913 914 void record(MetaspaceObj::Type type, int byte_size, bool read_only) { 915 assert(int(type) >= 0 && type < MetaspaceObj::_number_of_types, "sanity"); 916 int which = (read_only) ? RO : RW; 917 _counts[which][type] ++; 918 _bytes [which][type] += byte_size; 919 } 920 921 void record_other_type(int byte_size, bool read_only) { 922 int which = (read_only) ? RO : RW; 923 _bytes [which][OtherType] += byte_size; 924 } 925 void print_stats(int ro_all, int rw_all, int mc_all, int md_all); 926 }; 927 928 void DumpAllocStats::print_stats(int ro_all, int rw_all, int mc_all, int md_all) { 929 // Calculate size of data that was not allocated by Metaspace::allocate() 930 MetaspaceSharedStats *stats = MetaspaceShared::stats(); 931 932 // symbols 933 _counts[RO][SymbolHashentryType] = stats->symbol.hashentry_count; 934 _bytes [RO][SymbolHashentryType] = stats->symbol.hashentry_bytes; 935 936 _counts[RO][SymbolBucketType] = stats->symbol.bucket_count; 937 _bytes [RO][SymbolBucketType] = stats->symbol.bucket_bytes; 938 939 // strings 940 _counts[RO][StringHashentryType] = stats->string.hashentry_count; 941 _bytes [RO][StringHashentryType] = stats->string.hashentry_bytes; 942 943 _counts[RO][StringBucketType] = stats->string.bucket_count; 944 _bytes [RO][StringBucketType] = stats->string.bucket_bytes; 945 946 // TODO: count things like dictionary, vtable, etc 947 _bytes[RW][OtherType] += mc_all + md_all; 948 rw_all += mc_all + md_all; // mc/md are mapped Read/Write 949 950 // prevent divide-by-zero 951 if (ro_all < 1) { 952 ro_all = 1; 953 } 954 if (rw_all < 1) { 955 rw_all = 1; 956 } 957 958 int all_ro_count = 0; 959 int all_ro_bytes = 0; 960 int all_rw_count = 0; 961 int all_rw_bytes = 0; 962 963 // To make fmt_stats be a syntactic constant (for format warnings), use #define. 964 #define fmt_stats "%-20s: %8d %10d %5.1f | %8d %10d %5.1f | %8d %10d %5.1f" 965 const char *sep = "--------------------+---------------------------+---------------------------+--------------------------"; 966 const char *hdr = " ro_cnt ro_bytes % | rw_cnt rw_bytes % | all_cnt all_bytes %"; 967 968 LogMessage(cds) msg; 969 970 msg.info("Detailed metadata info (excluding od/st regions; rw stats include md/mc regions):"); 971 msg.info("%s", hdr); 972 msg.info("%s", sep); 973 for (int type = 0; type < int(_number_of_types); type ++) { 974 const char *name = type_name((Type)type); 975 int ro_count = _counts[RO][type]; 976 int ro_bytes = _bytes [RO][type]; 977 int rw_count = _counts[RW][type]; 978 int rw_bytes = _bytes [RW][type]; 979 int count = ro_count + rw_count; 980 int bytes = ro_bytes + rw_bytes; 981 982 double ro_perc = percent_of(ro_bytes, ro_all); 983 double rw_perc = percent_of(rw_bytes, rw_all); 984 double perc = percent_of(bytes, ro_all + rw_all); 985 986 msg.info(fmt_stats, name, 987 ro_count, ro_bytes, ro_perc, 988 rw_count, rw_bytes, rw_perc, 989 count, bytes, perc); 990 991 all_ro_count += ro_count; 992 all_ro_bytes += ro_bytes; 993 all_rw_count += rw_count; 994 all_rw_bytes += rw_bytes; 995 } 996 997 int all_count = all_ro_count + all_rw_count; 998 int all_bytes = all_ro_bytes + all_rw_bytes; 999 1000 double all_ro_perc = percent_of(all_ro_bytes, ro_all); 1001 double all_rw_perc = percent_of(all_rw_bytes, rw_all); 1002 double all_perc = percent_of(all_bytes, ro_all + rw_all); 1003 1004 msg.info("%s", sep); 1005 msg.info(fmt_stats, "Total", 1006 all_ro_count, all_ro_bytes, all_ro_perc, 1007 all_rw_count, all_rw_bytes, all_rw_perc, 1008 all_count, all_bytes, all_perc); 1009 1010 assert(all_ro_bytes == ro_all, "everything should have been counted"); 1011 assert(all_rw_bytes == rw_all, "everything should have been counted"); 1012 1013 #undef fmt_stats 1014 } 1015 1016 // Populate the shared space. 1017 1018 class VM_PopulateDumpSharedSpace: public VM_Operation { 1019 private: 1020 GrowableArray<MemRegion> *_closed_archive_heap_regions; 1021 GrowableArray<MemRegion> *_open_archive_heap_regions; 1022 1023 GrowableArray<ArchiveHeapOopmapInfo> *_closed_archive_heap_oopmaps; 1024 GrowableArray<ArchiveHeapOopmapInfo> *_open_archive_heap_oopmaps; 1025 1026 void dump_java_heap_objects() NOT_CDS_JAVA_HEAP_RETURN; 1027 void dump_archive_heap_oopmaps() NOT_CDS_JAVA_HEAP_RETURN; 1028 void dump_archive_heap_oopmaps(GrowableArray<MemRegion>* regions, 1029 GrowableArray<ArchiveHeapOopmapInfo>* oopmaps); 1030 void dump_symbols(); 1031 char* dump_read_only_tables(); 1032 void print_region_stats(); 1033 void print_heap_region_stats(GrowableArray<MemRegion> *heap_mem, 1034 const char *name, const size_t total_size); 1035 public: 1036 1037 VMOp_Type type() const { return VMOp_PopulateDumpSharedSpace; } 1038 void doit(); // outline because gdb sucks 1039 static void write_region(FileMapInfo* mapinfo, int region, DumpRegion* space, bool read_only, bool allow_exec); 1040 bool allow_nested_vm_operations() const { return true; } 1041 }; // class VM_PopulateDumpSharedSpace 1042 1043 class SortedSymbolClosure: public SymbolClosure { 1044 GrowableArray<Symbol*> _symbols; 1045 virtual void do_symbol(Symbol** sym) { 1046 assert((*sym)->is_permanent(), "archived symbols must be permanent"); 1047 _symbols.append(*sym); 1048 } 1049 static int compare_symbols_by_address(Symbol** a, Symbol** b) { 1050 if (a[0] < b[0]) { 1051 return -1; 1052 } else if (a[0] == b[0]) { 1053 return 0; 1054 } else { 1055 return 1; 1056 } 1057 } 1058 1059 public: 1060 SortedSymbolClosure() { 1061 SymbolTable::symbols_do(this); 1062 _symbols.sort(compare_symbols_by_address); 1063 } 1064 GrowableArray<Symbol*>* get_sorted_symbols() { 1065 return &_symbols; 1066 } 1067 }; 1068 1069 // ArchiveCompactor -- 1070 // 1071 // This class is the central piece of shared archive compaction -- all metaspace data are 1072 // initially allocated outside of the shared regions. ArchiveCompactor copies the 1073 // metaspace data into their final location in the shared regions. 1074 1075 class ArchiveCompactor : AllStatic { 1076 static DumpAllocStats* _alloc_stats; 1077 static SortedSymbolClosure* _ssc; 1078 1079 static unsigned my_hash(const address& a) { 1080 return primitive_hash<address>(a); 1081 } 1082 static bool my_equals(const address& a0, const address& a1) { 1083 return primitive_equals<address>(a0, a1); 1084 } 1085 typedef ResourceHashtable< 1086 address, address, 1087 ArchiveCompactor::my_hash, // solaris compiler doesn't like: primitive_hash<address> 1088 ArchiveCompactor::my_equals, // solaris compiler doesn't like: primitive_equals<address> 1089 16384, ResourceObj::C_HEAP> RelocationTable; 1090 static RelocationTable* _new_loc_table; 1091 1092 public: 1093 static void initialize() { 1094 _alloc_stats = new(ResourceObj::C_HEAP, mtInternal)DumpAllocStats; 1095 _new_loc_table = new(ResourceObj::C_HEAP, mtInternal)RelocationTable; 1096 } 1097 static DumpAllocStats* alloc_stats() { 1098 return _alloc_stats; 1099 } 1100 1101 static void allocate(MetaspaceClosure::Ref* ref, bool read_only) { 1102 address obj = ref->obj(); 1103 int bytes = ref->size() * BytesPerWord; 1104 char* p; 1105 size_t alignment = BytesPerWord; 1106 char* oldtop; 1107 char* newtop; 1108 1109 if (read_only) { 1110 oldtop = _ro_region.top(); 1111 p = _ro_region.allocate(bytes, alignment); 1112 newtop = _ro_region.top(); 1113 } else { 1114 oldtop = _rw_region.top(); 1115 p = _rw_region.allocate(bytes, alignment); 1116 newtop = _rw_region.top(); 1117 } 1118 memcpy(p, obj, bytes); 1119 bool isnew = _new_loc_table->put(obj, (address)p); 1120 log_trace(cds)("Copy: " PTR_FORMAT " ==> " PTR_FORMAT " %d", p2i(obj), p2i(p), bytes); 1121 assert(isnew, "must be"); 1122 1123 _alloc_stats->record(ref->msotype(), int(newtop - oldtop), read_only); 1124 if (ref->msotype() == MetaspaceObj::SymbolType) { 1125 uintx delta = MetaspaceShared::object_delta(p); 1126 if (delta > MAX_SHARED_DELTA) { 1127 // This is just a sanity check and should not appear in any real world usage. This 1128 // happens only if you allocate more than 2GB of Symbols and would require 1129 // millions of shared classes. 1130 vm_exit_during_initialization("Too many Symbols in the CDS archive", 1131 "Please reduce the number of shared classes."); 1132 } 1133 } 1134 } 1135 1136 static address get_new_loc(MetaspaceClosure::Ref* ref) { 1137 address* pp = _new_loc_table->get(ref->obj()); 1138 assert(pp != NULL, "must be"); 1139 return *pp; 1140 } 1141 1142 private: 1143 // Makes a shallow copy of visited MetaspaceObj's 1144 class ShallowCopier: public UniqueMetaspaceClosure { 1145 bool _read_only; 1146 public: 1147 ShallowCopier(bool read_only) : _read_only(read_only) {} 1148 1149 virtual void do_unique_ref(Ref* ref, bool read_only) { 1150 if (read_only == _read_only) { 1151 allocate(ref, read_only); 1152 } 1153 } 1154 }; 1155 1156 // Relocate embedded pointers within a MetaspaceObj's shallow copy 1157 class ShallowCopyEmbeddedRefRelocator: public UniqueMetaspaceClosure { 1158 public: 1159 virtual void do_unique_ref(Ref* ref, bool read_only) { 1160 address new_loc = get_new_loc(ref); 1161 RefRelocator refer; 1162 ref->metaspace_pointers_do_at(&refer, new_loc); 1163 } 1164 }; 1165 1166 // Relocate a reference to point to its shallow copy 1167 class RefRelocator: public MetaspaceClosure { 1168 public: 1169 virtual bool do_ref(Ref* ref, bool read_only) { 1170 if (ref->not_null()) { 1171 ref->update(get_new_loc(ref)); 1172 } 1173 return false; // Do not recurse. 1174 } 1175 }; 1176 1177 #ifdef ASSERT 1178 class IsRefInArchiveChecker: public MetaspaceClosure { 1179 public: 1180 virtual bool do_ref(Ref* ref, bool read_only) { 1181 if (ref->not_null()) { 1182 char* obj = (char*)ref->obj(); 1183 assert(_ro_region.contains(obj) || _rw_region.contains(obj), 1184 "must be relocated to point to CDS archive"); 1185 } 1186 return false; // Do not recurse. 1187 } 1188 }; 1189 #endif 1190 1191 public: 1192 static void copy_and_compact() { 1193 // We should no longer allocate anything from the metaspace, so that 1194 // we can have a stable set of MetaspaceObjs to work with. 1195 Metaspace::freeze(); 1196 1197 ResourceMark rm; 1198 SortedSymbolClosure the_ssc; // StackObj 1199 _ssc = &the_ssc; 1200 1201 tty->print_cr("Scanning all metaspace objects ... "); 1202 { 1203 // allocate and shallow-copy RW objects, immediately following the MC region 1204 tty->print_cr("Allocating RW objects ... "); 1205 _mc_region.pack(&_rw_region); 1206 1207 ResourceMark rm; 1208 ShallowCopier rw_copier(false); 1209 iterate_roots(&rw_copier); 1210 } 1211 { 1212 // allocate and shallow-copy of RO object, immediately following the RW region 1213 tty->print_cr("Allocating RO objects ... "); 1214 _rw_region.pack(&_ro_region); 1215 1216 ResourceMark rm; 1217 ShallowCopier ro_copier(true); 1218 iterate_roots(&ro_copier); 1219 } 1220 { 1221 tty->print_cr("Relocating embedded pointers ... "); 1222 ResourceMark rm; 1223 ShallowCopyEmbeddedRefRelocator emb_reloc; 1224 iterate_roots(&emb_reloc); 1225 } 1226 { 1227 tty->print_cr("Relocating external roots ... "); 1228 ResourceMark rm; 1229 RefRelocator ext_reloc; 1230 iterate_roots(&ext_reloc); 1231 } 1232 1233 #ifdef ASSERT 1234 { 1235 tty->print_cr("Verifying external roots ... "); 1236 ResourceMark rm; 1237 IsRefInArchiveChecker checker; 1238 iterate_roots(&checker); 1239 } 1240 #endif 1241 1242 1243 // cleanup 1244 _ssc = NULL; 1245 } 1246 1247 // We must relocate the System::_well_known_klasses only after we have copied the 1248 // java objects in during dump_java_heap_objects(): during the object copy, we operate on 1249 // old objects which assert that their klass is the original klass. 1250 static void relocate_well_known_klasses() { 1251 { 1252 tty->print_cr("Relocating SystemDictionary::_well_known_klasses[] ... "); 1253 ResourceMark rm; 1254 RefRelocator ext_reloc; 1255 SystemDictionary::well_known_klasses_do(&ext_reloc); 1256 } 1257 // NOTE: after this point, we shouldn't have any globals that can reach the old 1258 // objects. 1259 1260 // We cannot use any of the objects in the heap anymore (except for the objects 1261 // in the CDS shared string regions) because their headers no longer point to 1262 // valid Klasses. 1263 } 1264 1265 static void iterate_roots(MetaspaceClosure* it) { 1266 GrowableArray<Symbol*>* symbols = _ssc->get_sorted_symbols(); 1267 for (int i=0; i<symbols->length(); i++) { 1268 it->push(symbols->adr_at(i)); 1269 } 1270 if (_global_klass_objects != NULL) { 1271 // Need to fix up the pointers 1272 for (int i = 0; i < _global_klass_objects->length(); i++) { 1273 // NOTE -- this requires that the vtable is NOT yet patched, or else we are hosed. 1274 it->push(_global_klass_objects->adr_at(i)); 1275 } 1276 } 1277 FileMapInfo::metaspace_pointers_do(it); 1278 SystemDictionary::classes_do(it); 1279 Universe::metaspace_pointers_do(it); 1280 SymbolTable::metaspace_pointers_do(it); 1281 vmSymbols::metaspace_pointers_do(it); 1282 } 1283 1284 static Klass* get_relocated_klass(Klass* orig_klass) { 1285 assert(DumpSharedSpaces, "dump time only"); 1286 address* pp = _new_loc_table->get((address)orig_klass); 1287 assert(pp != NULL, "must be"); 1288 Klass* klass = (Klass*)(*pp); 1289 assert(klass->is_klass(), "must be"); 1290 return klass; 1291 } 1292 }; 1293 1294 DumpAllocStats* ArchiveCompactor::_alloc_stats; 1295 SortedSymbolClosure* ArchiveCompactor::_ssc; 1296 ArchiveCompactor::RelocationTable* ArchiveCompactor::_new_loc_table; 1297 1298 void VM_PopulateDumpSharedSpace::write_region(FileMapInfo* mapinfo, int region_idx, 1299 DumpRegion* dump_region, bool read_only, bool allow_exec) { 1300 mapinfo->write_region(region_idx, dump_region->base(), dump_region->used(), read_only, allow_exec); 1301 } 1302 1303 void VM_PopulateDumpSharedSpace::dump_symbols() { 1304 tty->print_cr("Dumping symbol table ..."); 1305 1306 NOT_PRODUCT(SymbolTable::verify()); 1307 SymbolTable::write_to_archive(); 1308 } 1309 1310 char* VM_PopulateDumpSharedSpace::dump_read_only_tables() { 1311 char* oldtop = _ro_region.top(); 1312 // Reorder the system dictionary. Moving the symbols affects 1313 // how the hash table indices are calculated. 1314 SystemDictionary::reorder_dictionary_for_sharing(); 1315 1316 tty->print("Removing java_mirror ... "); 1317 if (!MetaspaceShared::is_heap_object_archiving_allowed()) { 1318 clear_basic_type_mirrors(); 1319 } 1320 remove_java_mirror_in_classes(); 1321 tty->print_cr("done. "); 1322 NOT_PRODUCT(SystemDictionary::verify();) 1323 1324 size_t buckets_bytes = SystemDictionary::count_bytes_for_buckets(); 1325 char* buckets_top = _ro_region.allocate(buckets_bytes, sizeof(intptr_t)); 1326 SystemDictionary::copy_buckets(buckets_top, _ro_region.top()); 1327 1328 size_t table_bytes = SystemDictionary::count_bytes_for_table(); 1329 char* table_top = _ro_region.allocate(table_bytes, sizeof(intptr_t)); 1330 SystemDictionary::copy_table(table_top, _ro_region.top()); 1331 1332 // Write the archived object sub-graph infos. For each klass with sub-graphs, 1333 // the info includes the static fields (sub-graph entry points) and Klasses 1334 // of objects included in the sub-graph. 1335 HeapShared::write_archived_subgraph_infos(); 1336 1337 // Write the other data to the output array. 1338 WriteClosure wc(&_ro_region); 1339 MetaspaceShared::serialize(&wc); 1340 1341 // Write the bitmaps for patching the archive heap regions 1342 dump_archive_heap_oopmaps(); 1343 1344 char* newtop = _ro_region.top(); 1345 ArchiveCompactor::alloc_stats()->record_other_type(int(newtop - oldtop), true); 1346 return buckets_top; 1347 } 1348 1349 void VM_PopulateDumpSharedSpace::doit() { 1350 Thread* THREAD = VMThread::vm_thread(); 1351 1352 FileMapInfo::check_nonempty_dir_in_shared_path_table(); 1353 1354 NOT_PRODUCT(SystemDictionary::verify();) 1355 // The following guarantee is meant to ensure that no loader constraints 1356 // exist yet, since the constraints table is not shared. This becomes 1357 // more important now that we don't re-initialize vtables/itables for 1358 // shared classes at runtime, where constraints were previously created. 1359 guarantee(SystemDictionary::constraints()->number_of_entries() == 0, 1360 "loader constraints are not saved"); 1361 guarantee(SystemDictionary::placeholders()->number_of_entries() == 0, 1362 "placeholders are not saved"); 1363 // Revisit and implement this if we prelink method handle call sites: 1364 guarantee(SystemDictionary::invoke_method_table() == NULL || 1365 SystemDictionary::invoke_method_table()->number_of_entries() == 0, 1366 "invoke method table is not saved"); 1367 1368 // At this point, many classes have been loaded. 1369 // Gather systemDictionary classes in a global array and do everything to 1370 // that so we don't have to walk the SystemDictionary again. 1371 _global_klass_objects = new GrowableArray<Klass*>(1000); 1372 CollectClassesClosure collect_classes; 1373 ClassLoaderDataGraph::loaded_classes_do(&collect_classes); 1374 1375 tty->print_cr("Number of classes %d", _global_klass_objects->length()); 1376 { 1377 int num_type_array = 0, num_obj_array = 0, num_inst = 0; 1378 for (int i = 0; i < _global_klass_objects->length(); i++) { 1379 Klass* k = _global_klass_objects->at(i); 1380 if (k->is_instance_klass()) { 1381 num_inst ++; 1382 } else if (k->is_objArray_klass()) { 1383 num_obj_array ++; 1384 } else { 1385 assert(k->is_typeArray_klass(), "sanity"); 1386 num_type_array ++; 1387 } 1388 } 1389 tty->print_cr(" instance classes = %5d", num_inst); 1390 tty->print_cr(" obj array classes = %5d", num_obj_array); 1391 tty->print_cr(" type array classes = %5d", num_type_array); 1392 } 1393 1394 // Ensure the ConstMethods won't be modified at run-time 1395 tty->print("Updating ConstMethods ... "); 1396 rewrite_nofast_bytecodes_and_calculate_fingerprints(); 1397 tty->print_cr("done. "); 1398 1399 // Move classes from platform/system dictionaries into the boot dictionary 1400 SystemDictionary::combine_shared_dictionaries(); 1401 1402 // Make sure all classes have a correct loader type. 1403 ClassLoaderData::the_null_class_loader_data()->dictionary()->classes_do(MetaspaceShared::check_shared_class_loader_type); 1404 1405 // Remove all references outside the metadata 1406 tty->print("Removing unshareable information ... "); 1407 remove_unshareable_in_classes(); 1408 tty->print_cr("done. "); 1409 1410 // We don't support archiving anonymous classes. Verify that they are not stored in 1411 // the any dictionaries. 1412 NOT_PRODUCT(assert_no_anonymoys_classes_in_dictionaries()); 1413 1414 SystemDictionaryShared::finalize_verification_constraints(); 1415 1416 ArchiveCompactor::initialize(); 1417 ArchiveCompactor::copy_and_compact(); 1418 1419 dump_symbols(); 1420 1421 // Dump supported java heap objects 1422 _closed_archive_heap_regions = NULL; 1423 _open_archive_heap_regions = NULL; 1424 dump_java_heap_objects(); 1425 1426 ArchiveCompactor::relocate_well_known_klasses(); 1427 1428 char* read_only_tables_start = dump_read_only_tables(); 1429 _ro_region.pack(&_md_region); 1430 1431 char* vtbl_list = _md_region.top(); 1432 MetaspaceShared::allocate_cpp_vtable_clones(); 1433 _md_region.pack(&_od_region); 1434 1435 // Relocate the archived class file data into the od region 1436 relocate_cached_class_file(); 1437 _od_region.pack(); 1438 1439 // The 5 core spaces are allocated consecutively mc->rw->ro->md->od, so there total size 1440 // is just the spaces between the two ends. 1441 size_t core_spaces_size = _od_region.end() - _mc_region.base(); 1442 assert(core_spaces_size == (size_t)align_up(core_spaces_size, Metaspace::reserve_alignment()), 1443 "should already be aligned"); 1444 1445 // During patching, some virtual methods may be called, so at this point 1446 // the vtables must contain valid methods (as filled in by CppVtableCloner::allocate). 1447 MetaspaceShared::patch_cpp_vtable_pointers(); 1448 1449 // The vtable clones contain addresses of the current process. 1450 // We don't want to write these addresses into the archive. 1451 MetaspaceShared::zero_cpp_vtable_clones_for_writing(); 1452 1453 // Create and write the archive file that maps the shared spaces. 1454 1455 FileMapInfo* mapinfo = new FileMapInfo(); 1456 mapinfo->populate_header(os::vm_allocation_granularity()); 1457 mapinfo->set_read_only_tables_start(read_only_tables_start); 1458 mapinfo->set_misc_data_patching_start(vtbl_list); 1459 mapinfo->set_cds_i2i_entry_code_buffers(MetaspaceShared::cds_i2i_entry_code_buffers()); 1460 mapinfo->set_cds_i2i_entry_code_buffers_size(MetaspaceShared::cds_i2i_entry_code_buffers_size()); 1461 mapinfo->set_core_spaces_size(core_spaces_size); 1462 1463 for (int pass=1; pass<=2; pass++) { 1464 if (pass == 1) { 1465 // The first pass doesn't actually write the data to disk. All it 1466 // does is to update the fields in the mapinfo->_header. 1467 } else { 1468 // After the first pass, the contents of mapinfo->_header are finalized, 1469 // so we can compute the header's CRC, and write the contents of the header 1470 // and the regions into disk. 1471 mapinfo->open_for_write(); 1472 mapinfo->set_header_crc(mapinfo->compute_header_crc()); 1473 } 1474 mapinfo->write_header(); 1475 1476 // NOTE: md contains the trampoline code for method entries, which are patched at run time, 1477 // so it needs to be read/write. 1478 write_region(mapinfo, MetaspaceShared::mc, &_mc_region, /*read_only=*/false,/*allow_exec=*/true); 1479 write_region(mapinfo, MetaspaceShared::rw, &_rw_region, /*read_only=*/false,/*allow_exec=*/false); 1480 write_region(mapinfo, MetaspaceShared::ro, &_ro_region, /*read_only=*/true, /*allow_exec=*/false); 1481 write_region(mapinfo, MetaspaceShared::md, &_md_region, /*read_only=*/false,/*allow_exec=*/false); 1482 write_region(mapinfo, MetaspaceShared::od, &_od_region, /*read_only=*/true, /*allow_exec=*/false); 1483 1484 _total_string_region_size = mapinfo->write_archive_heap_regions( 1485 _closed_archive_heap_regions, 1486 _closed_archive_heap_oopmaps, 1487 MetaspaceShared::first_string, 1488 MetaspaceShared::max_strings); 1489 _total_open_archive_region_size = mapinfo->write_archive_heap_regions( 1490 _open_archive_heap_regions, 1491 _open_archive_heap_oopmaps, 1492 MetaspaceShared::first_open_archive_heap_region, 1493 MetaspaceShared::max_open_archive_heap_region); 1494 } 1495 1496 mapinfo->close(); 1497 1498 // Restore the vtable in case we invoke any virtual methods. 1499 MetaspaceShared::clone_cpp_vtables((intptr_t*)vtbl_list); 1500 1501 print_region_stats(); 1502 1503 if (log_is_enabled(Info, cds)) { 1504 ArchiveCompactor::alloc_stats()->print_stats(int(_ro_region.used()), int(_rw_region.used()), 1505 int(_mc_region.used()), int(_md_region.used())); 1506 } 1507 1508 if (PrintSystemDictionaryAtExit) { 1509 SystemDictionary::print(); 1510 } 1511 // There may be other pending VM operations that operate on the InstanceKlasses, 1512 // which will fail because InstanceKlasses::remove_unshareable_info() 1513 // has been called. Forget these operations and exit the VM directly. 1514 vm_direct_exit(0); 1515 } 1516 1517 void VM_PopulateDumpSharedSpace::print_region_stats() { 1518 // Print statistics of all the regions 1519 const size_t total_reserved = _ro_region.reserved() + _rw_region.reserved() + 1520 _mc_region.reserved() + _md_region.reserved() + 1521 _od_region.reserved() + 1522 _total_string_region_size + 1523 _total_open_archive_region_size; 1524 const size_t total_bytes = _ro_region.used() + _rw_region.used() + 1525 _mc_region.used() + _md_region.used() + 1526 _od_region.used() + 1527 _total_string_region_size + 1528 _total_open_archive_region_size; 1529 const double total_u_perc = percent_of(total_bytes, total_reserved); 1530 1531 _mc_region.print(total_reserved); 1532 _rw_region.print(total_reserved); 1533 _ro_region.print(total_reserved); 1534 _md_region.print(total_reserved); 1535 _od_region.print(total_reserved); 1536 print_heap_region_stats(_closed_archive_heap_regions, "st", total_reserved); 1537 print_heap_region_stats(_open_archive_heap_regions, "oa", total_reserved); 1538 1539 tty->print_cr("total : " SIZE_FORMAT_W(9) " [100.0%% of total] out of " SIZE_FORMAT_W(9) " bytes [%5.1f%% used]", 1540 total_bytes, total_reserved, total_u_perc); 1541 } 1542 1543 void VM_PopulateDumpSharedSpace::print_heap_region_stats(GrowableArray<MemRegion> *heap_mem, 1544 const char *name, const size_t total_size) { 1545 int arr_len = heap_mem == NULL ? 0 : heap_mem->length(); 1546 for (int i = 0; i < arr_len; i++) { 1547 char* start = (char*)heap_mem->at(i).start(); 1548 size_t size = heap_mem->at(i).byte_size(); 1549 char* top = start + size; 1550 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, 1551 name, i, size, size/double(total_size)*100.0, size, p2i(start)); 1552 1553 } 1554 } 1555 1556 // Update a Java object to point its Klass* to the new location after 1557 // shared archive has been compacted. 1558 void MetaspaceShared::relocate_klass_ptr(oop o) { 1559 assert(DumpSharedSpaces, "sanity"); 1560 Klass* k = ArchiveCompactor::get_relocated_klass(o->klass()); 1561 o->set_klass(k); 1562 } 1563 1564 Klass* MetaspaceShared::get_relocated_klass(Klass *k) { 1565 assert(DumpSharedSpaces, "sanity"); 1566 return ArchiveCompactor::get_relocated_klass(k); 1567 } 1568 1569 class LinkSharedClassesClosure : public KlassClosure { 1570 Thread* THREAD; 1571 bool _made_progress; 1572 public: 1573 LinkSharedClassesClosure(Thread* thread) : THREAD(thread), _made_progress(false) {} 1574 1575 void reset() { _made_progress = false; } 1576 bool made_progress() const { return _made_progress; } 1577 1578 void do_klass(Klass* k) { 1579 if (k->is_instance_klass()) { 1580 InstanceKlass* ik = InstanceKlass::cast(k); 1581 // Link the class to cause the bytecodes to be rewritten and the 1582 // cpcache to be created. Class verification is done according 1583 // to -Xverify setting. 1584 _made_progress |= MetaspaceShared::try_link_class(ik, THREAD); 1585 guarantee(!HAS_PENDING_EXCEPTION, "exception in link_class"); 1586 1587 ik->constants()->resolve_class_constants(THREAD); 1588 } 1589 } 1590 }; 1591 1592 class CheckSharedClassesClosure : public KlassClosure { 1593 bool _made_progress; 1594 public: 1595 CheckSharedClassesClosure() : _made_progress(false) {} 1596 1597 void reset() { _made_progress = false; } 1598 bool made_progress() const { return _made_progress; } 1599 void do_klass(Klass* k) { 1600 if (k->is_instance_klass() && InstanceKlass::cast(k)->check_sharing_error_state()) { 1601 _made_progress = true; 1602 } 1603 } 1604 }; 1605 1606 void MetaspaceShared::check_shared_class_loader_type(InstanceKlass* ik) { 1607 ResourceMark rm; 1608 if (ik->shared_classpath_index() == UNREGISTERED_INDEX) { 1609 guarantee(ik->loader_type() == 0, 1610 "Class loader type must not be set for this class %s", ik->name()->as_C_string()); 1611 } else { 1612 guarantee(ik->loader_type() != 0, 1613 "Class loader type must be set for this class %s", ik->name()->as_C_string()); 1614 } 1615 } 1616 1617 void MetaspaceShared::link_and_cleanup_shared_classes(TRAPS) { 1618 // We need to iterate because verification may cause additional classes 1619 // to be loaded. 1620 LinkSharedClassesClosure link_closure(THREAD); 1621 do { 1622 link_closure.reset(); 1623 ClassLoaderDataGraph::loaded_classes_do(&link_closure); 1624 guarantee(!HAS_PENDING_EXCEPTION, "exception in link_class"); 1625 } while (link_closure.made_progress()); 1626 1627 if (_has_error_classes) { 1628 // Mark all classes whose super class or interfaces failed verification. 1629 CheckSharedClassesClosure check_closure; 1630 do { 1631 // Not completely sure if we need to do this iteratively. Anyway, 1632 // we should come here only if there are unverifiable classes, which 1633 // shouldn't happen in normal cases. So better safe than sorry. 1634 check_closure.reset(); 1635 ClassLoaderDataGraph::loaded_classes_do(&check_closure); 1636 } while (check_closure.made_progress()); 1637 1638 if (IgnoreUnverifiableClassesDuringDump) { 1639 // This is useful when running JCK or SQE tests. You should not 1640 // enable this when running real apps. 1641 SystemDictionary::remove_classes_in_error_state(); 1642 } else { 1643 tty->print_cr("Please remove the unverifiable classes from your class list and try again"); 1644 exit(1); 1645 } 1646 } 1647 } 1648 1649 void MetaspaceShared::prepare_for_dumping() { 1650 Arguments::check_unsupported_dumping_properties(); 1651 ClassLoader::initialize_shared_path(); 1652 } 1653 1654 // Preload classes from a list, populate the shared spaces and dump to a 1655 // file. 1656 void MetaspaceShared::preload_and_dump(TRAPS) { 1657 { TraceTime timer("Dump Shared Spaces", TRACETIME_LOG(Info, startuptime)); 1658 ResourceMark rm; 1659 char class_list_path_str[JVM_MAXPATHLEN]; 1660 // Preload classes to be shared. 1661 // Should use some os:: method rather than fopen() here. aB. 1662 const char* class_list_path; 1663 if (SharedClassListFile == NULL) { 1664 // Construct the path to the class list (in jre/lib) 1665 // Walk up two directories from the location of the VM and 1666 // optionally tack on "lib" (depending on platform) 1667 os::jvm_path(class_list_path_str, sizeof(class_list_path_str)); 1668 for (int i = 0; i < 3; i++) { 1669 char *end = strrchr(class_list_path_str, *os::file_separator()); 1670 if (end != NULL) *end = '\0'; 1671 } 1672 int class_list_path_len = (int)strlen(class_list_path_str); 1673 if (class_list_path_len >= 3) { 1674 if (strcmp(class_list_path_str + class_list_path_len - 3, "lib") != 0) { 1675 if (class_list_path_len < JVM_MAXPATHLEN - 4) { 1676 jio_snprintf(class_list_path_str + class_list_path_len, 1677 sizeof(class_list_path_str) - class_list_path_len, 1678 "%slib", os::file_separator()); 1679 class_list_path_len += 4; 1680 } 1681 } 1682 } 1683 if (class_list_path_len < JVM_MAXPATHLEN - 10) { 1684 jio_snprintf(class_list_path_str + class_list_path_len, 1685 sizeof(class_list_path_str) - class_list_path_len, 1686 "%sclasslist", os::file_separator()); 1687 } 1688 class_list_path = class_list_path_str; 1689 } else { 1690 class_list_path = SharedClassListFile; 1691 } 1692 1693 tty->print_cr("Loading classes to share ..."); 1694 _has_error_classes = false; 1695 int class_count = preload_classes(class_list_path, THREAD); 1696 if (ExtraSharedClassListFile) { 1697 class_count += preload_classes(ExtraSharedClassListFile, THREAD); 1698 } 1699 tty->print_cr("Loading classes to share: done."); 1700 1701 log_info(cds)("Shared spaces: preloaded %d classes", class_count); 1702 1703 // Rewrite and link classes 1704 tty->print_cr("Rewriting and linking classes ..."); 1705 1706 // Link any classes which got missed. This would happen if we have loaded classes that 1707 // were not explicitly specified in the classlist. E.g., if an interface implemented by class K 1708 // fails verification, all other interfaces that were not specified in the classlist but 1709 // are implemented by K are not verified. 1710 link_and_cleanup_shared_classes(CATCH); 1711 tty->print_cr("Rewriting and linking classes: done"); 1712 1713 SystemDictionary::clear_invoke_method_table(); 1714 HeapShared::init_archivable_static_fields(THREAD); 1715 1716 VM_PopulateDumpSharedSpace op; 1717 VMThread::execute(&op); 1718 } 1719 } 1720 1721 1722 int MetaspaceShared::preload_classes(const char* class_list_path, TRAPS) { 1723 ClassListParser parser(class_list_path); 1724 int class_count = 0; 1725 1726 while (parser.parse_one_line()) { 1727 Klass* klass = ClassLoaderExt::load_one_class(&parser, THREAD); 1728 if (HAS_PENDING_EXCEPTION) { 1729 if (klass == NULL && 1730 (PENDING_EXCEPTION->klass()->name() == vmSymbols::java_lang_ClassNotFoundException())) { 1731 // print a warning only when the pending exception is class not found 1732 tty->print_cr("Preload Warning: Cannot find %s", parser.current_class_name()); 1733 } 1734 CLEAR_PENDING_EXCEPTION; 1735 } 1736 if (klass != NULL) { 1737 if (log_is_enabled(Trace, cds)) { 1738 ResourceMark rm; 1739 log_trace(cds)("Shared spaces preloaded: %s", klass->external_name()); 1740 } 1741 1742 if (klass->is_instance_klass()) { 1743 InstanceKlass* ik = InstanceKlass::cast(klass); 1744 1745 // Link the class to cause the bytecodes to be rewritten and the 1746 // cpcache to be created. The linking is done as soon as classes 1747 // are loaded in order that the related data structures (klass and 1748 // cpCache) are located together. 1749 try_link_class(ik, THREAD); 1750 guarantee(!HAS_PENDING_EXCEPTION, "exception in link_class"); 1751 } 1752 1753 class_count++; 1754 } 1755 } 1756 1757 return class_count; 1758 } 1759 1760 // Returns true if the class's status has changed 1761 bool MetaspaceShared::try_link_class(InstanceKlass* ik, TRAPS) { 1762 assert(DumpSharedSpaces, "should only be called during dumping"); 1763 if (ik->init_state() < InstanceKlass::linked) { 1764 bool saved = BytecodeVerificationLocal; 1765 if (ik->loader_type() == 0 && ik->class_loader() == NULL) { 1766 // The verification decision is based on BytecodeVerificationRemote 1767 // for non-system classes. Since we are using the NULL classloader 1768 // to load non-system classes for customized class loaders during dumping, 1769 // we need to temporarily change BytecodeVerificationLocal to be the same as 1770 // BytecodeVerificationRemote. Note this can cause the parent system 1771 // classes also being verified. The extra overhead is acceptable during 1772 // dumping. 1773 BytecodeVerificationLocal = BytecodeVerificationRemote; 1774 } 1775 ik->link_class(THREAD); 1776 if (HAS_PENDING_EXCEPTION) { 1777 ResourceMark rm; 1778 tty->print_cr("Preload Warning: Verification failed for %s", 1779 ik->external_name()); 1780 CLEAR_PENDING_EXCEPTION; 1781 ik->set_in_error_state(); 1782 _has_error_classes = true; 1783 } 1784 BytecodeVerificationLocal = saved; 1785 return true; 1786 } else { 1787 return false; 1788 } 1789 } 1790 1791 #if INCLUDE_CDS_JAVA_HEAP 1792 void VM_PopulateDumpSharedSpace::dump_java_heap_objects() { 1793 if (!MetaspaceShared::is_heap_object_archiving_allowed()) { 1794 if (log_is_enabled(Info, cds)) { 1795 log_info(cds)( 1796 "Archived java heap is not supported as UseG1GC, " 1797 "UseCompressedOops and UseCompressedClassPointers are required." 1798 "Current settings: UseG1GC=%s, UseCompressedOops=%s, UseCompressedClassPointers=%s.", 1799 BOOL_TO_STR(UseG1GC), BOOL_TO_STR(UseCompressedOops), 1800 BOOL_TO_STR(UseCompressedClassPointers)); 1801 } 1802 return; 1803 } 1804 1805 { 1806 NoSafepointVerifier nsv; 1807 1808 // Cache for recording where the archived objects are copied to 1809 MetaspaceShared::create_archive_object_cache(); 1810 1811 tty->print_cr("Dumping objects to closed archive heap region ..."); 1812 NOT_PRODUCT(StringTable::verify()); 1813 // The closed space has maximum two regions. See FileMapInfo::write_archive_heap_regions() for details. 1814 _closed_archive_heap_regions = new GrowableArray<MemRegion>(2); 1815 MetaspaceShared::dump_closed_archive_heap_objects(_closed_archive_heap_regions); 1816 1817 tty->print_cr("Dumping objects to open archive heap region ..."); 1818 _open_archive_heap_regions = new GrowableArray<MemRegion>(2); 1819 MetaspaceShared::dump_open_archive_heap_objects(_open_archive_heap_regions); 1820 1821 MetaspaceShared::destroy_archive_object_cache(); 1822 } 1823 1824 G1HeapVerifier::verify_archive_regions(); 1825 } 1826 1827 void VM_PopulateDumpSharedSpace::dump_archive_heap_oopmaps() { 1828 if (MetaspaceShared::is_heap_object_archiving_allowed()) { 1829 _closed_archive_heap_oopmaps = new GrowableArray<ArchiveHeapOopmapInfo>(2); 1830 dump_archive_heap_oopmaps(_closed_archive_heap_regions, _closed_archive_heap_oopmaps); 1831 1832 _open_archive_heap_oopmaps = new GrowableArray<ArchiveHeapOopmapInfo>(2); 1833 dump_archive_heap_oopmaps(_open_archive_heap_regions, _open_archive_heap_oopmaps); 1834 } 1835 } 1836 1837 void VM_PopulateDumpSharedSpace::dump_archive_heap_oopmaps(GrowableArray<MemRegion>* regions, 1838 GrowableArray<ArchiveHeapOopmapInfo>* oopmaps) { 1839 for (int i=0; i<regions->length(); i++) { 1840 ResourceBitMap oopmap = HeapShared::calculate_oopmap(regions->at(i)); 1841 size_t size_in_bits = oopmap.size(); 1842 size_t size_in_bytes = oopmap.size_in_bytes(); 1843 uintptr_t* buffer = (uintptr_t*)_ro_region.allocate(size_in_bytes, sizeof(intptr_t)); 1844 oopmap.write_to(buffer, size_in_bytes); 1845 log_info(cds)("Oopmap = " INTPTR_FORMAT " (" SIZE_FORMAT_W(6) " bytes) for heap region " 1846 INTPTR_FORMAT " (" SIZE_FORMAT_W(8) " bytes)", 1847 p2i(buffer), size_in_bytes, 1848 p2i(regions->at(i).start()), regions->at(i).byte_size()); 1849 1850 ArchiveHeapOopmapInfo info; 1851 info._oopmap = (address)buffer; 1852 info._oopmap_size_in_bits = size_in_bits; 1853 oopmaps->append(info); 1854 } 1855 } 1856 1857 void MetaspaceShared::dump_closed_archive_heap_objects( 1858 GrowableArray<MemRegion> * closed_archive) { 1859 assert(is_heap_object_archiving_allowed(), "Cannot dump java heap objects"); 1860 1861 Thread* THREAD = Thread::current(); 1862 G1CollectedHeap::heap()->begin_archive_alloc_range(); 1863 1864 // Archive interned string objects 1865 StringTable::write_to_archive(); 1866 1867 G1CollectedHeap::heap()->end_archive_alloc_range(closed_archive, 1868 os::vm_allocation_granularity()); 1869 } 1870 1871 void MetaspaceShared::dump_open_archive_heap_objects( 1872 GrowableArray<MemRegion> * open_archive) { 1873 assert(UseG1GC, "Only support G1 GC"); 1874 assert(UseCompressedOops && UseCompressedClassPointers, 1875 "Only support UseCompressedOops and UseCompressedClassPointers enabled"); 1876 1877 Thread* THREAD = Thread::current(); 1878 G1CollectedHeap::heap()->begin_archive_alloc_range(true /* open */); 1879 1880 java_lang_Class::archive_basic_type_mirrors(THREAD); 1881 1882 MetaspaceShared::archive_klass_objects(THREAD); 1883 1884 HeapShared::archive_module_graph_objects(THREAD); 1885 1886 G1CollectedHeap::heap()->end_archive_alloc_range(open_archive, 1887 os::vm_allocation_granularity()); 1888 } 1889 1890 unsigned MetaspaceShared::obj_hash(oop const& p) { 1891 assert(!p->mark()->has_bias_pattern(), 1892 "this object should never have been locked"); // so identity_hash won't safepoin 1893 unsigned hash = (unsigned)p->identity_hash(); 1894 return hash; 1895 } 1896 1897 MetaspaceShared::ArchivedObjectCache* MetaspaceShared::_archive_object_cache = NULL; 1898 oop MetaspaceShared::find_archived_heap_object(oop obj) { 1899 assert(DumpSharedSpaces, "dump-time only"); 1900 ArchivedObjectCache* cache = MetaspaceShared::archive_object_cache(); 1901 oop* p = cache->get(obj); 1902 if (p != NULL) { 1903 return *p; 1904 } else { 1905 return NULL; 1906 } 1907 } 1908 1909 oop MetaspaceShared::archive_heap_object(oop obj, Thread* THREAD) { 1910 assert(DumpSharedSpaces, "dump-time only"); 1911 1912 oop ao = find_archived_heap_object(obj); 1913 if (ao != NULL) { 1914 // already archived 1915 return ao; 1916 } 1917 1918 int len = obj->size(); 1919 if (G1CollectedHeap::heap()->is_archive_alloc_too_large(len)) { 1920 log_debug(cds, heap)("Cannot archive, object (" PTR_FORMAT ") is too large: " SIZE_FORMAT, 1921 p2i(obj), (size_t)obj->size()); 1922 return NULL; 1923 } 1924 1925 int hash = obj->identity_hash(); 1926 oop archived_oop = (oop)G1CollectedHeap::heap()->archive_mem_allocate(len); 1927 if (archived_oop != NULL) { 1928 Copy::aligned_disjoint_words((HeapWord*)obj, (HeapWord*)archived_oop, len); 1929 relocate_klass_ptr(archived_oop); 1930 ArchivedObjectCache* cache = MetaspaceShared::archive_object_cache(); 1931 cache->put(obj, archived_oop); 1932 log_debug(cds, heap)("Archived heap object " PTR_FORMAT " ==> " PTR_FORMAT, 1933 p2i(obj), p2i(archived_oop)); 1934 } else { 1935 log_error(cds, heap)( 1936 "Cannot allocate space for object " PTR_FORMAT " in archived heap region", 1937 p2i(obj)); 1938 vm_exit(1); 1939 } 1940 return archived_oop; 1941 } 1942 1943 oop MetaspaceShared::materialize_archived_object(narrowOop v) { 1944 if (!CompressedOops::is_null(v)) { 1945 oop obj = HeapShared::decode_with_archived_oop_encoding_mode(v); 1946 return G1CollectedHeap::heap()->materialize_archived_object(obj); 1947 } 1948 return NULL; 1949 } 1950 1951 void MetaspaceShared::archive_klass_objects(Thread* THREAD) { 1952 int i; 1953 for (i = 0; i < _global_klass_objects->length(); i++) { 1954 Klass* k = _global_klass_objects->at(i); 1955 1956 // archive mirror object 1957 java_lang_Class::archive_mirror(k, CHECK); 1958 1959 // archive the resolved_referenes array 1960 if (k->is_instance_klass()) { 1961 InstanceKlass* ik = InstanceKlass::cast(k); 1962 ik->constants()->archive_resolved_references(THREAD); 1963 } 1964 } 1965 } 1966 1967 bool MetaspaceShared::is_archive_object(oop p) { 1968 return (p == NULL) ? false : G1ArchiveAllocator::is_archive_object(p); 1969 } 1970 1971 void MetaspaceShared::fixup_mapped_heap_regions() { 1972 FileMapInfo *mapinfo = FileMapInfo::current_info(); 1973 mapinfo->fixup_mapped_heap_regions(); 1974 } 1975 #endif // INCLUDE_CDS_JAVA_HEAP 1976 1977 // Closure for serializing initialization data in from a data area 1978 // (ptr_array) read from the shared file. 1979 1980 class ReadClosure : public SerializeClosure { 1981 private: 1982 intptr_t** _ptr_array; 1983 1984 inline intptr_t nextPtr() { 1985 return *(*_ptr_array)++; 1986 } 1987 1988 public: 1989 ReadClosure(intptr_t** ptr_array) { _ptr_array = ptr_array; } 1990 1991 void do_ptr(void** p) { 1992 assert(*p == NULL, "initializing previous initialized pointer."); 1993 intptr_t obj = nextPtr(); 1994 assert((intptr_t)obj >= 0 || (intptr_t)obj < -100, 1995 "hit tag while initializing ptrs."); 1996 *p = (void*)obj; 1997 } 1998 1999 void do_u4(u4* p) { 2000 intptr_t obj = nextPtr(); 2001 *p = (u4)(uintx(obj)); 2002 } 2003 2004 void do_tag(int tag) { 2005 int old_tag; 2006 old_tag = (int)(intptr_t)nextPtr(); 2007 // do_int(&old_tag); 2008 assert(tag == old_tag, "old tag doesn't match"); 2009 FileMapInfo::assert_mark(tag == old_tag); 2010 } 2011 2012 void do_oop(oop *p) { 2013 narrowOop o = (narrowOop)nextPtr(); 2014 if (o == 0 || !MetaspaceShared::open_archive_heap_region_mapped()) { 2015 p = NULL; 2016 } else { 2017 assert(MetaspaceShared::is_heap_object_archiving_allowed(), 2018 "Archived heap object is not allowed"); 2019 assert(MetaspaceShared::open_archive_heap_region_mapped(), 2020 "Open archive heap region is not mapped"); 2021 *p = HeapShared::decode_with_archived_oop_encoding_mode(o); 2022 } 2023 } 2024 2025 void do_region(u_char* start, size_t size) { 2026 assert((intptr_t)start % sizeof(intptr_t) == 0, "bad alignment"); 2027 assert(size % sizeof(intptr_t) == 0, "bad size"); 2028 do_tag((int)size); 2029 while (size > 0) { 2030 *(intptr_t*)start = nextPtr(); 2031 start += sizeof(intptr_t); 2032 size -= sizeof(intptr_t); 2033 } 2034 } 2035 2036 bool reading() const { return true; } 2037 }; 2038 2039 // Return true if given address is in the misc data region 2040 bool MetaspaceShared::is_in_shared_region(const void* p, int idx) { 2041 return UseSharedSpaces && FileMapInfo::current_info()->is_in_shared_region(p, idx); 2042 } 2043 2044 bool MetaspaceShared::is_in_trampoline_frame(address addr) { 2045 if (UseSharedSpaces && is_in_shared_region(addr, MetaspaceShared::mc)) { 2046 return true; 2047 } 2048 return false; 2049 } 2050 2051 // Map shared spaces at requested addresses and return if succeeded. 2052 bool MetaspaceShared::map_shared_spaces(FileMapInfo* mapinfo) { 2053 size_t image_alignment = mapinfo->alignment(); 2054 2055 #ifndef _WINDOWS 2056 // Map in the shared memory and then map the regions on top of it. 2057 // On Windows, don't map the memory here because it will cause the 2058 // mappings of the regions to fail. 2059 ReservedSpace shared_rs = mapinfo->reserve_shared_memory(); 2060 if (!shared_rs.is_reserved()) return false; 2061 #endif 2062 2063 assert(!DumpSharedSpaces, "Should not be called with DumpSharedSpaces"); 2064 2065 char* ro_base = NULL; char* ro_top; 2066 char* rw_base = NULL; char* rw_top; 2067 char* mc_base = NULL; char* mc_top; 2068 char* md_base = NULL; char* md_top; 2069 char* od_base = NULL; char* od_top; 2070 2071 // Map each shared region 2072 if ((mc_base = mapinfo->map_region(mc, &mc_top)) != NULL && 2073 (rw_base = mapinfo->map_region(rw, &rw_top)) != NULL && 2074 (ro_base = mapinfo->map_region(ro, &ro_top)) != NULL && 2075 (md_base = mapinfo->map_region(md, &md_top)) != NULL && 2076 (od_base = mapinfo->map_region(od, &od_top)) != NULL && 2077 (image_alignment == (size_t)os::vm_allocation_granularity()) && 2078 mapinfo->validate_shared_path_table()) { 2079 // Success -- set up MetaspaceObj::_shared_metaspace_{base,top} for 2080 // fast checking in MetaspaceShared::is_in_shared_metaspace() and 2081 // MetaspaceObj::is_shared(). 2082 // 2083 // We require that mc->rw->ro->md->od to be laid out consecutively, with no 2084 // gaps between them. That way, we can ensure that the OS won't be able to 2085 // allocate any new memory spaces inside _shared_metaspace_{base,top}, which 2086 // would mess up the simple comparision in MetaspaceShared::is_in_shared_metaspace(). 2087 assert(mc_base < ro_base && mc_base < rw_base && mc_base < md_base && mc_base < od_base, "must be"); 2088 assert(od_top > ro_top && od_top > rw_top && od_top > md_top && od_top > mc_top , "must be"); 2089 assert(mc_top == rw_base, "must be"); 2090 assert(rw_top == ro_base, "must be"); 2091 assert(ro_top == md_base, "must be"); 2092 assert(md_top == od_base, "must be"); 2093 2094 MetaspaceObj::set_shared_metaspace_range((void*)mc_base, (void*)od_top); 2095 return true; 2096 } else { 2097 // If there was a failure in mapping any of the spaces, unmap the ones 2098 // that succeeded 2099 if (ro_base != NULL) mapinfo->unmap_region(ro); 2100 if (rw_base != NULL) mapinfo->unmap_region(rw); 2101 if (mc_base != NULL) mapinfo->unmap_region(mc); 2102 if (md_base != NULL) mapinfo->unmap_region(md); 2103 if (od_base != NULL) mapinfo->unmap_region(od); 2104 #ifndef _WINDOWS 2105 // Release the entire mapped region 2106 shared_rs.release(); 2107 #endif 2108 // If -Xshare:on is specified, print out the error message and exit VM, 2109 // otherwise, set UseSharedSpaces to false and continue. 2110 if (RequireSharedSpaces || PrintSharedArchiveAndExit) { 2111 vm_exit_during_initialization("Unable to use shared archive.", "Failed map_region for using -Xshare:on."); 2112 } else { 2113 FLAG_SET_DEFAULT(UseSharedSpaces, false); 2114 } 2115 return false; 2116 } 2117 } 2118 2119 // Read the miscellaneous data from the shared file, and 2120 // serialize it out to its various destinations. 2121 2122 void MetaspaceShared::initialize_shared_spaces() { 2123 FileMapInfo *mapinfo = FileMapInfo::current_info(); 2124 _cds_i2i_entry_code_buffers = mapinfo->cds_i2i_entry_code_buffers(); 2125 _cds_i2i_entry_code_buffers_size = mapinfo->cds_i2i_entry_code_buffers_size(); 2126 _core_spaces_size = mapinfo->core_spaces_size(); 2127 char* buffer = mapinfo->misc_data_patching_start(); 2128 clone_cpp_vtables((intptr_t*)buffer); 2129 2130 // The rest of the data is now stored in the RW region 2131 buffer = mapinfo->read_only_tables_start(); 2132 int sharedDictionaryLen = *(intptr_t*)buffer; 2133 buffer += sizeof(intptr_t); 2134 int number_of_entries = *(intptr_t*)buffer; 2135 buffer += sizeof(intptr_t); 2136 SystemDictionary::set_shared_dictionary((HashtableBucket<mtClass>*)buffer, 2137 sharedDictionaryLen, 2138 number_of_entries); 2139 buffer += sharedDictionaryLen; 2140 2141 // The following data are the linked list elements 2142 // (HashtableEntry objects) for the shared dictionary table. 2143 2144 int len = *(intptr_t*)buffer; // skip over shared dictionary entries 2145 buffer += sizeof(intptr_t); 2146 buffer += len; 2147 2148 // The table of archived java heap object sub-graph infos 2149 buffer = HeapShared::read_archived_subgraph_infos(buffer); 2150 2151 // Verify various attributes of the archive, plus initialize the 2152 // shared string/symbol tables 2153 intptr_t* array = (intptr_t*)buffer; 2154 ReadClosure rc(&array); 2155 serialize(&rc); 2156 2157 // Initialize the run-time symbol table. 2158 SymbolTable::create_table(); 2159 2160 mapinfo->patch_archived_heap_embedded_pointers(); 2161 2162 // Close the mapinfo file 2163 mapinfo->close(); 2164 2165 if (PrintSharedArchiveAndExit) { 2166 if (PrintSharedDictionary) { 2167 tty->print_cr("\nShared classes:\n"); 2168 SystemDictionary::print_shared(tty); 2169 } 2170 if (_archive_loading_failed) { 2171 tty->print_cr("archive is invalid"); 2172 vm_exit(1); 2173 } else { 2174 tty->print_cr("archive is valid"); 2175 vm_exit(0); 2176 } 2177 } 2178 } 2179 2180 // JVM/TI RedefineClasses() support: 2181 bool MetaspaceShared::remap_shared_readonly_as_readwrite() { 2182 assert(SafepointSynchronize::is_at_safepoint(), "must be at safepoint"); 2183 2184 if (UseSharedSpaces) { 2185 // remap the shared readonly space to shared readwrite, private 2186 FileMapInfo* mapinfo = FileMapInfo::current_info(); 2187 if (!mapinfo->remap_shared_readonly_as_readwrite()) { 2188 return false; 2189 } 2190 _remapped_readwrite = true; 2191 } 2192 return true; 2193 } 2194 2195 void MetaspaceShared::report_out_of_space(const char* name, size_t needed_bytes) { 2196 // This is highly unlikely to happen on 64-bits because we have reserved a 4GB space. 2197 // On 32-bit we reserve only 256MB so you could run out of space with 100,000 classes 2198 // or so. 2199 _mc_region.print_out_of_space_msg(name, needed_bytes); 2200 _rw_region.print_out_of_space_msg(name, needed_bytes); 2201 _ro_region.print_out_of_space_msg(name, needed_bytes); 2202 _md_region.print_out_of_space_msg(name, needed_bytes); 2203 _od_region.print_out_of_space_msg(name, needed_bytes); 2204 2205 vm_exit_during_initialization(err_msg("Unable to allocate from '%s' region", name), 2206 "Please reduce the number of shared classes."); 2207 }