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