1 /* 2 * Copyright (c) 2012, 2017, 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 "classfile/classListParser.hpp" 27 #include "classfile/classLoaderExt.hpp" 28 #include "classfile/dictionary.hpp" 29 #include "classfile/loaderConstraints.hpp" 30 #include "classfile/placeholders.hpp" 31 #include "classfile/sharedClassUtil.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 #if INCLUDE_ALL_GCS 38 #include "gc/g1/g1Allocator.inline.hpp" 39 #include "gc/g1/g1CollectedHeap.hpp" 40 #include "gc/g1/g1SATBCardTableModRefBS.hpp" 41 #endif 42 #include "gc/shared/gcLocker.hpp" 43 #include "interpreter/bytecodeStream.hpp" 44 #include "interpreter/bytecodes.hpp" 45 #include "logging/log.hpp" 46 #include "logging/logMessage.hpp" 47 #include "memory/filemap.hpp" 48 #include "memory/metaspace.hpp" 49 #include "memory/metaspaceShared.hpp" 50 #include "memory/resourceArea.hpp" 51 #include "oops/instanceClassLoaderKlass.hpp" 52 #include "oops/instanceMirrorKlass.hpp" 53 #include "oops/instanceRefKlass.hpp" 54 #include "oops/objArrayKlass.hpp" 55 #include "oops/objArrayOop.hpp" 56 #include "oops/oop.inline.hpp" 57 #include "oops/typeArrayKlass.hpp" 58 #include "prims/jvm.h" 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 double perc(size_t used, size_t total) const { 161 if (total == 0) { 162 total = 1; 163 } 164 return used / double(total) * 100.0; 165 } 166 167 void print(size_t total_bytes) const { 168 tty->print_cr("%s space: " SIZE_FORMAT_W(9) " [ %4.1f%% of total] out of " SIZE_FORMAT_W(9) " bytes [%5.1f%% used] at " INTPTR_FORMAT, 169 _name, used(), perc(used(), total_bytes), reserved(), perc(used(), reserved()), p2i(_base)); 170 } 171 void print_out_of_space_msg(const char* failing_region, size_t needed_bytes) { 172 tty->print("[%-8s] " PTR_FORMAT " - " PTR_FORMAT " capacity =%9d, allocated =%9d", 173 _name, p2i(_base), p2i(_top), int(_end - _base), int(_top - _base)); 174 if (strcmp(_name, failing_region) == 0) { 175 tty->print_cr(" required = %d", int(needed_bytes)); 176 } else { 177 tty->cr(); 178 } 179 } 180 181 void init(const ReservedSpace* rs) { 182 _base = _top = rs->base(); 183 _end = rs->end(); 184 } 185 void init(char* b, char* t, char* e) { 186 _base = b; 187 _top = t; 188 _end = e; 189 } 190 191 void pack(DumpRegion* next = NULL) { 192 assert(!is_packed(), "sanity"); 193 _end = (char*)align_up(_top, Metaspace::reserve_alignment()); 194 _is_packed = true; 195 if (next != NULL) { 196 next->_base = next->_top = this->_end; 197 next->_end = MetaspaceShared::shared_rs()->end(); 198 } 199 } 200 bool contains(char* p) { 201 return base() <= p && p < top(); 202 } 203 }; 204 205 206 DumpRegion _mc_region("mc"), _ro_region("ro"), _rw_region("rw"), _md_region("md"), _od_region("od"); 207 size_t _total_string_region_size = 0, _total_open_archive_region_size = 0; 208 209 char* MetaspaceShared::misc_code_space_alloc(size_t num_bytes) { 210 return _mc_region.allocate(num_bytes); 211 } 212 213 char* MetaspaceShared::read_only_space_alloc(size_t num_bytes) { 214 return _ro_region.allocate(num_bytes); 215 } 216 217 void MetaspaceShared::initialize_shared_rs() { 218 const size_t reserve_alignment = Metaspace::reserve_alignment(); 219 bool large_pages = false; // No large pages when dumping the CDS archive. 220 char* shared_base = (char*)align_up((char*)SharedBaseAddress, reserve_alignment); 221 222 #ifdef _LP64 223 // On 64-bit VM, the heap and class space layout will be the same as if 224 // you're running in -Xshare:on mode: 225 // 226 // +-- SharedBaseAddress (default = 0x800000000) 227 // v 228 // +-..---------+----+ ... +----+----+----+----+----+---------------+ 229 // | Heap | ST | | MC | RW | RO | MD | OD | class space | 230 // +-..---------+----+ ... +----+----+----+----+----+---------------+ 231 // |<--MaxHeapSize->| |<-- UnscaledClassSpaceMax = 4GB ------->| 232 // 233 const uint64_t UnscaledClassSpaceMax = (uint64_t(max_juint) + 1); 234 const size_t cds_total = align_down(UnscaledClassSpaceMax, reserve_alignment); 235 #else 236 // We don't support archives larger than 256MB on 32-bit due to limited virtual address space. 237 size_t cds_total = align_down(256*M, reserve_alignment); 238 #endif 239 240 // First try to reserve the space at the specified SharedBaseAddress. 241 _shared_rs = ReservedSpace(cds_total, reserve_alignment, large_pages, shared_base); 242 if (_shared_rs.is_reserved()) { 243 assert(shared_base == 0 || _shared_rs.base() == shared_base, "should match"); 244 } else { 245 // Get a mmap region anywhere if the SharedBaseAddress fails. 246 _shared_rs = ReservedSpace(cds_total, reserve_alignment, large_pages); 247 } 248 if (!_shared_rs.is_reserved()) { 249 vm_exit_during_initialization("Unable to reserve memory for shared space", 250 err_msg(SIZE_FORMAT " bytes.", cds_total)); 251 } 252 253 #ifdef _LP64 254 // During dump time, we allocate 4GB (UnscaledClassSpaceMax) of space and split it up: 255 // + The upper 1 GB is used as the "temporary compressed class space" -- preload_classes() 256 // will store Klasses into this space. 257 // + The lower 3 GB is used for the archive -- when preload_classes() is done, 258 // ArchiveCompactor will copy the class metadata into this space, first the RW parts, 259 // then the RO parts. 260 261 assert(UseCompressedOops && UseCompressedClassPointers, 262 "UseCompressedOops and UseCompressedClassPointers must be set"); 263 264 size_t max_archive_size = align_down(cds_total * 3 / 4, reserve_alignment); 265 ReservedSpace tmp_class_space = _shared_rs.last_part(max_archive_size); 266 CompressedClassSpaceSize = align_down(tmp_class_space.size(), reserve_alignment); 267 _shared_rs = _shared_rs.first_part(max_archive_size); 268 269 // Set up compress class pointers. 270 Universe::set_narrow_klass_base((address)_shared_rs.base()); 271 if (UseAOT || cds_total > UnscaledClassSpaceMax) { 272 // AOT forces narrow_klass_shift=LogKlassAlignmentInBytes 273 Universe::set_narrow_klass_shift(LogKlassAlignmentInBytes); 274 } else { 275 Universe::set_narrow_klass_shift(0); 276 } 277 278 Metaspace::initialize_class_space(tmp_class_space); 279 tty->print_cr("narrow_klass_base = " PTR_FORMAT ", narrow_klass_shift = %d", 280 p2i(Universe::narrow_klass_base()), Universe::narrow_klass_shift()); 281 282 tty->print_cr("Allocated temporary class space: " SIZE_FORMAT " bytes at " PTR_FORMAT, 283 CompressedClassSpaceSize, p2i(tmp_class_space.base())); 284 #endif 285 286 // Start with 0 committed bytes. The memory will be committed as needed by 287 // MetaspaceShared::commit_shared_space_to(). 288 if (!_shared_vs.initialize(_shared_rs, 0)) { 289 vm_exit_during_initialization("Unable to allocate memory for shared space"); 290 } 291 292 _mc_region.init(&_shared_rs); 293 tty->print_cr("Allocated shared space: " SIZE_FORMAT " bytes at " PTR_FORMAT, 294 _shared_rs.size(), p2i(_shared_rs.base())); 295 } 296 297 void MetaspaceShared::commit_shared_space_to(char* newtop) { 298 assert(DumpSharedSpaces, "dump-time only"); 299 char* base = _shared_rs.base(); 300 size_t need_committed_size = newtop - base; 301 size_t has_committed_size = _shared_vs.committed_size(); 302 if (need_committed_size < has_committed_size) { 303 return; 304 } 305 306 size_t min_bytes = need_committed_size - has_committed_size; 307 size_t preferred_bytes = 1 * M; 308 size_t uncommitted = _shared_vs.reserved_size() - has_committed_size; 309 310 size_t commit = MAX2(min_bytes, preferred_bytes); 311 assert(commit <= uncommitted, "sanity"); 312 313 bool result = _shared_vs.expand_by(commit, false); 314 if (!result) { 315 vm_exit_during_initialization(err_msg("Failed to expand shared space to " SIZE_FORMAT " bytes", 316 need_committed_size)); 317 } 318 319 log_info(cds)("Expanding shared spaces by " SIZE_FORMAT_W(7) " bytes [total " SIZE_FORMAT_W(9) " bytes ending at %p]", 320 commit, _shared_vs.actual_committed_size(), _shared_vs.high()); 321 } 322 323 // Read/write a data stream for restoring/preserving metadata pointers and 324 // miscellaneous data from/to the shared archive file. 325 326 void MetaspaceShared::serialize(SerializeClosure* soc) { 327 int tag = 0; 328 soc->do_tag(--tag); 329 330 // Verify the sizes of various metadata in the system. 331 soc->do_tag(sizeof(Method)); 332 soc->do_tag(sizeof(ConstMethod)); 333 soc->do_tag(arrayOopDesc::base_offset_in_bytes(T_BYTE)); 334 soc->do_tag(sizeof(ConstantPool)); 335 soc->do_tag(sizeof(ConstantPoolCache)); 336 soc->do_tag(objArrayOopDesc::base_offset_in_bytes()); 337 soc->do_tag(typeArrayOopDesc::base_offset_in_bytes(T_BYTE)); 338 soc->do_tag(sizeof(Symbol)); 339 340 // Dump/restore miscellaneous metadata. 341 Universe::serialize(soc, true); 342 soc->do_tag(--tag); 343 344 // Dump/restore references to commonly used names and signatures. 345 vmSymbols::serialize(soc); 346 soc->do_tag(--tag); 347 348 // Dump/restore the symbol and string tables 349 SymbolTable::serialize(soc); 350 StringTable::serialize(soc); 351 soc->do_tag(--tag); 352 353 soc->do_tag(666); 354 } 355 356 address MetaspaceShared::cds_i2i_entry_code_buffers(size_t total_size) { 357 if (DumpSharedSpaces) { 358 if (_cds_i2i_entry_code_buffers == NULL) { 359 _cds_i2i_entry_code_buffers = (address)misc_code_space_alloc(total_size); 360 _cds_i2i_entry_code_buffers_size = total_size; 361 } 362 } else if (UseSharedSpaces) { 363 assert(_cds_i2i_entry_code_buffers != NULL, "must already been initialized"); 364 } else { 365 return NULL; 366 } 367 368 assert(_cds_i2i_entry_code_buffers_size == total_size, "must not change"); 369 return _cds_i2i_entry_code_buffers; 370 } 371 372 // CDS code for dumping shared archive. 373 374 // Global object for holding classes that have been loaded. Since this 375 // is run at a safepoint just before exit, this is the entire set of classes. 376 static GrowableArray<Klass*>* _global_klass_objects; 377 class CollectClassesClosure : public KlassClosure { 378 void do_klass(Klass* k) { 379 if (!(k->is_instance_klass() && InstanceKlass::cast(k)->is_in_error_state())) { 380 _global_klass_objects->append_if_missing(k); 381 } 382 } 383 }; 384 385 static void remove_unshareable_in_classes() { 386 for (int i = 0; i < _global_klass_objects->length(); i++) { 387 Klass* k = _global_klass_objects->at(i); 388 k->remove_unshareable_info(); 389 } 390 } 391 392 static void rewrite_nofast_bytecode(Method* method) { 393 RawBytecodeStream bcs(method); 394 while (!bcs.is_last_bytecode()) { 395 Bytecodes::Code opcode = bcs.raw_next(); 396 switch (opcode) { 397 case Bytecodes::_getfield: *bcs.bcp() = Bytecodes::_nofast_getfield; break; 398 case Bytecodes::_putfield: *bcs.bcp() = Bytecodes::_nofast_putfield; break; 399 case Bytecodes::_aload_0: *bcs.bcp() = Bytecodes::_nofast_aload_0; break; 400 case Bytecodes::_iload: { 401 if (!bcs.is_wide()) { 402 *bcs.bcp() = Bytecodes::_nofast_iload; 403 } 404 break; 405 } 406 default: break; 407 } 408 } 409 } 410 411 // Walk all methods in the class list to ensure that they won't be modified at 412 // run time. This includes: 413 // [1] Rewrite all bytecodes as needed, so that the ConstMethod* will not be modified 414 // at run time by RewriteBytecodes/RewriteFrequentPairs 415 // [2] Assign a fingerprint, so one doesn't need to be assigned at run-time. 416 static void rewrite_nofast_bytecodes_and_calculate_fingerprints() { 417 for (int i = 0; i < _global_klass_objects->length(); i++) { 418 Klass* k = _global_klass_objects->at(i); 419 if (k->is_instance_klass()) { 420 InstanceKlass* ik = InstanceKlass::cast(k); 421 for (int i = 0; i < ik->methods()->length(); i++) { 422 Method* m = ik->methods()->at(i); 423 rewrite_nofast_bytecode(m); 424 Fingerprinter fp(m); 425 // The side effect of this call sets method's fingerprint field. 426 fp.fingerprint(); 427 } 428 } 429 } 430 } 431 432 static void relocate_cached_class_file() { 433 for (int i = 0; i < _global_klass_objects->length(); i++) { 434 Klass* k = _global_klass_objects->at(i); 435 if (k->is_instance_klass()) { 436 InstanceKlass* ik = InstanceKlass::cast(k); 437 JvmtiCachedClassFileData* p = ik->get_archived_class_data(); 438 if (p != NULL) { 439 int size = offset_of(JvmtiCachedClassFileData, data) + p->length; 440 JvmtiCachedClassFileData* q = (JvmtiCachedClassFileData*)_od_region.allocate(size); 441 q->length = p->length; 442 memcpy(q->data, p->data, p->length); 443 ik->set_archived_class_data(q); 444 } 445 } 446 } 447 } 448 449 // Objects of the Metadata types (such as Klass and ConstantPool) have C++ vtables. 450 // (In GCC this is the field <Type>::_vptr, i.e., first word in the object.) 451 // 452 // Addresses of the vtables and the methods may be different across JVM runs, 453 // if libjvm.so is dynamically loaded at a different base address. 454 // 455 // To ensure that the Metadata objects in the CDS archive always have the correct vtable: 456 // 457 // + at dump time: we redirect the _vptr to point to our own vtables inside 458 // the CDS image 459 // + at run time: we clone the actual contents of the vtables from libjvm.so 460 // into our own tables. 461 462 // Currently, the archive contain ONLY the following types of objects that have C++ vtables. 463 #define CPP_VTABLE_PATCH_TYPES_DO(f) \ 464 f(ConstantPool) \ 465 f(InstanceKlass) \ 466 f(InstanceClassLoaderKlass) \ 467 f(InstanceMirrorKlass) \ 468 f(InstanceRefKlass) \ 469 f(Method) \ 470 f(ObjArrayKlass) \ 471 f(TypeArrayKlass) 472 473 class CppVtableInfo { 474 intptr_t _vtable_size; 475 intptr_t _cloned_vtable[1]; 476 public: 477 static int num_slots(int vtable_size) { 478 return 1 + vtable_size; // Need to add the space occupied by _vtable_size; 479 } 480 int vtable_size() { return int(uintx(_vtable_size)); } 481 void set_vtable_size(int n) { _vtable_size = intptr_t(n); } 482 intptr_t* cloned_vtable() { return &_cloned_vtable[0]; } 483 void zero() { memset(_cloned_vtable, 0, sizeof(intptr_t) * vtable_size()); } 484 // Returns the address of the next CppVtableInfo that can be placed immediately after this CppVtableInfo 485 static size_t byte_size(int vtable_size) { 486 CppVtableInfo i; 487 return pointer_delta(&i._cloned_vtable[vtable_size], &i, sizeof(u1)); 488 } 489 }; 490 491 template <class T> class CppVtableCloner : public T { 492 static intptr_t* vtable_of(Metadata& m) { 493 return *((intptr_t**)&m); 494 } 495 static CppVtableInfo* _info; 496 497 static int get_vtable_length(const char* name); 498 499 public: 500 // Allocate and initialize the C++ vtable, starting from top, but do not go past end. 501 static intptr_t* allocate(const char* name); 502 503 // Clone the vtable to ... 504 static intptr_t* clone_vtable(const char* name, CppVtableInfo* info); 505 506 static void zero_vtable_clone() { 507 assert(DumpSharedSpaces, "dump-time only"); 508 _info->zero(); 509 } 510 511 // Switch the vtable pointer to point to the cloned vtable. 512 static void patch(Metadata* obj) { 513 assert(DumpSharedSpaces, "dump-time only"); 514 *(void**)obj = (void*)(_info->cloned_vtable()); 515 } 516 517 static bool is_valid_shared_object(const T* obj) { 518 intptr_t* vptr = *(intptr_t**)obj; 519 return vptr == _info->cloned_vtable(); 520 } 521 }; 522 523 template <class T> CppVtableInfo* CppVtableCloner<T>::_info = NULL; 524 525 template <class T> 526 intptr_t* CppVtableCloner<T>::allocate(const char* name) { 527 assert(is_aligned(_md_region.top(), sizeof(intptr_t)), "bad alignment"); 528 int n = get_vtable_length(name); 529 _info = (CppVtableInfo*)_md_region.allocate(CppVtableInfo::byte_size(n), sizeof(intptr_t)); 530 _info->set_vtable_size(n); 531 532 intptr_t* p = clone_vtable(name, _info); 533 assert((char*)p == _md_region.top(), "must be"); 534 535 return p; 536 } 537 538 template <class T> 539 intptr_t* CppVtableCloner<T>::clone_vtable(const char* name, CppVtableInfo* info) { 540 if (!DumpSharedSpaces) { 541 assert(_info == 0, "_info is initialized only at dump time"); 542 _info = info; // Remember it -- it will be used by MetaspaceShared::is_valid_shared_method() 543 } 544 T tmp; // Allocate temporary dummy metadata object to get to the original vtable. 545 int n = info->vtable_size(); 546 intptr_t* srcvtable = vtable_of(tmp); 547 intptr_t* dstvtable = info->cloned_vtable(); 548 549 // We already checked (and, if necessary, adjusted n) when the vtables were allocated, so we are 550 // safe to do memcpy. 551 log_debug(cds, vtables)("Copying %3d vtable entries for %s", n, name); 552 memcpy(dstvtable, srcvtable, sizeof(intptr_t) * n); 553 return dstvtable + n; 554 } 555 556 // To determine the size of the vtable for each type, we use the following 557 // trick by declaring 2 subclasses: 558 // 559 // class CppVtableTesterA: public InstanceKlass {virtual int last_virtual_method() {return 1;} }; 560 // class CppVtableTesterB: public InstanceKlass {virtual void* last_virtual_method() {return NULL}; }; 561 // 562 // CppVtableTesterA and CppVtableTesterB's vtables have the following properties: 563 // - Their size (N+1) is exactly one more than the size of InstanceKlass's vtable (N) 564 // - The first N entries have are exactly the same as in InstanceKlass's vtable. 565 // - Their last entry is different. 566 // 567 // So to determine the value of N, we just walk CppVtableTesterA and CppVtableTesterB's tables 568 // and find the first entry that's different. 569 // 570 // This works on all C++ compilers supported by Oracle, but you may need to tweak it for more 571 // esoteric compilers. 572 573 template <class T> class CppVtableTesterB: public T { 574 public: 575 virtual int last_virtual_method() {return 1;} 576 }; 577 578 template <class T> class CppVtableTesterA : public T { 579 public: 580 virtual void* last_virtual_method() { 581 // Make this different than CppVtableTesterB::last_virtual_method so the C++ 582 // compiler/linker won't alias the two functions. 583 return NULL; 584 } 585 }; 586 587 template <class T> 588 int CppVtableCloner<T>::get_vtable_length(const char* name) { 589 CppVtableTesterA<T> a; 590 CppVtableTesterB<T> b; 591 592 intptr_t* avtable = vtable_of(a); 593 intptr_t* bvtable = vtable_of(b); 594 595 // Start at slot 1, because slot 0 may be RTTI (on Solaris/Sparc) 596 int vtable_len = 1; 597 for (; ; vtable_len++) { 598 if (avtable[vtable_len] != bvtable[vtable_len]) { 599 break; 600 } 601 } 602 log_debug(cds, vtables)("Found %3d vtable entries for %s", vtable_len, name); 603 604 return vtable_len; 605 } 606 607 #define ALLOC_CPP_VTABLE_CLONE(c) \ 608 CppVtableCloner<c>::allocate(#c); 609 610 #define CLONE_CPP_VTABLE(c) \ 611 p = CppVtableCloner<c>::clone_vtable(#c, (CppVtableInfo*)p); 612 613 #define ZERO_CPP_VTABLE(c) \ 614 CppVtableCloner<c>::zero_vtable_clone(); 615 616 // This can be called at both dump time and run time. 617 intptr_t* MetaspaceShared::clone_cpp_vtables(intptr_t* p) { 618 assert(DumpSharedSpaces || UseSharedSpaces, "sanity"); 619 CPP_VTABLE_PATCH_TYPES_DO(CLONE_CPP_VTABLE); 620 return p; 621 } 622 623 void MetaspaceShared::zero_cpp_vtable_clones_for_writing() { 624 assert(DumpSharedSpaces, "dump-time only"); 625 CPP_VTABLE_PATCH_TYPES_DO(ZERO_CPP_VTABLE); 626 } 627 628 // Allocate and initialize the C++ vtables, starting from top, but do not go past end. 629 void MetaspaceShared::allocate_cpp_vtable_clones() { 630 assert(DumpSharedSpaces, "dump-time only"); 631 // Layout (each slot is a intptr_t): 632 // [number of slots in the first vtable = n1] 633 // [ <n1> slots for the first vtable] 634 // [number of slots in the first second = n2] 635 // [ <n2> slots for the second vtable] 636 // ... 637 // The order of the vtables is the same as the CPP_VTAB_PATCH_TYPES_DO macro. 638 CPP_VTABLE_PATCH_TYPES_DO(ALLOC_CPP_VTABLE_CLONE); 639 } 640 641 // Switch the vtable pointer to point to the cloned vtable. We assume the 642 // vtable pointer is in first slot in object. 643 void MetaspaceShared::patch_cpp_vtable_pointers() { 644 int n = _global_klass_objects->length(); 645 for (int i = 0; i < n; i++) { 646 Klass* obj = _global_klass_objects->at(i); 647 if (obj->is_instance_klass()) { 648 InstanceKlass* ik = InstanceKlass::cast(obj); 649 if (ik->is_class_loader_instance_klass()) { 650 CppVtableCloner<InstanceClassLoaderKlass>::patch(ik); 651 } else if (ik->is_reference_instance_klass()) { 652 CppVtableCloner<InstanceRefKlass>::patch(ik); 653 } else if (ik->is_mirror_instance_klass()) { 654 CppVtableCloner<InstanceMirrorKlass>::patch(ik); 655 } else { 656 CppVtableCloner<InstanceKlass>::patch(ik); 657 } 658 ConstantPool* cp = ik->constants(); 659 CppVtableCloner<ConstantPool>::patch(cp); 660 for (int j = 0; j < ik->methods()->length(); j++) { 661 Method* m = ik->methods()->at(j); 662 CppVtableCloner<Method>::patch(m); 663 assert(CppVtableCloner<Method>::is_valid_shared_object(m), "must be"); 664 } 665 } else if (obj->is_objArray_klass()) { 666 CppVtableCloner<ObjArrayKlass>::patch(obj); 667 } else { 668 assert(obj->is_typeArray_klass(), "sanity"); 669 CppVtableCloner<TypeArrayKlass>::patch(obj); 670 } 671 } 672 } 673 674 bool MetaspaceShared::is_valid_shared_method(const Method* m) { 675 assert(is_in_shared_space(m), "must be"); 676 return CppVtableCloner<Method>::is_valid_shared_object(m); 677 } 678 679 // Closure for serializing initialization data out to a data area to be 680 // written to the shared file. 681 682 class WriteClosure : public SerializeClosure { 683 private: 684 DumpRegion* _dump_region; 685 686 public: 687 WriteClosure(DumpRegion* r) { 688 _dump_region = r; 689 } 690 691 void do_ptr(void** p) { 692 _dump_region->append_intptr_t((intptr_t)*p); 693 } 694 695 void do_u4(u4* p) { 696 void* ptr = (void*)(uintx(*p)); 697 do_ptr(&ptr); 698 } 699 700 void do_tag(int tag) { 701 _dump_region->append_intptr_t((intptr_t)tag); 702 } 703 704 void do_region(u_char* start, size_t size) { 705 assert((intptr_t)start % sizeof(intptr_t) == 0, "bad alignment"); 706 assert(size % sizeof(intptr_t) == 0, "bad size"); 707 do_tag((int)size); 708 while (size > 0) { 709 _dump_region->append_intptr_t(*(intptr_t*)start); 710 start += sizeof(intptr_t); 711 size -= sizeof(intptr_t); 712 } 713 } 714 715 bool reading() const { return false; } 716 }; 717 718 // This is for dumping detailed statistics for the allocations 719 // in the shared spaces. 720 class DumpAllocStats : public ResourceObj { 721 public: 722 723 // Here's poor man's enum inheritance 724 #define SHAREDSPACE_OBJ_TYPES_DO(f) \ 725 METASPACE_OBJ_TYPES_DO(f) \ 726 f(SymbolHashentry) \ 727 f(SymbolBucket) \ 728 f(StringHashentry) \ 729 f(StringBucket) \ 730 f(Other) 731 732 enum Type { 733 // Types are MetaspaceObj::ClassType, MetaspaceObj::SymbolType, etc 734 SHAREDSPACE_OBJ_TYPES_DO(METASPACE_OBJ_TYPE_DECLARE) 735 _number_of_types 736 }; 737 738 static const char * type_name(Type type) { 739 switch(type) { 740 SHAREDSPACE_OBJ_TYPES_DO(METASPACE_OBJ_TYPE_NAME_CASE) 741 default: 742 ShouldNotReachHere(); 743 return NULL; 744 } 745 } 746 747 public: 748 enum { RO = 0, RW = 1 }; 749 750 int _counts[2][_number_of_types]; 751 int _bytes [2][_number_of_types]; 752 753 DumpAllocStats() { 754 memset(_counts, 0, sizeof(_counts)); 755 memset(_bytes, 0, sizeof(_bytes)); 756 }; 757 758 void record(MetaspaceObj::Type type, int byte_size, bool read_only) { 759 assert(int(type) >= 0 && type < MetaspaceObj::_number_of_types, "sanity"); 760 int which = (read_only) ? RO : RW; 761 _counts[which][type] ++; 762 _bytes [which][type] += byte_size; 763 } 764 765 void record_other_type(int byte_size, bool read_only) { 766 int which = (read_only) ? RO : RW; 767 _bytes [which][OtherType] += byte_size; 768 } 769 void print_stats(int ro_all, int rw_all, int mc_all, int md_all); 770 }; 771 772 void DumpAllocStats::print_stats(int ro_all, int rw_all, int mc_all, int md_all) { 773 // Calculate size of data that was not allocated by Metaspace::allocate() 774 MetaspaceSharedStats *stats = MetaspaceShared::stats(); 775 776 // symbols 777 _counts[RO][SymbolHashentryType] = stats->symbol.hashentry_count; 778 _bytes [RO][SymbolHashentryType] = stats->symbol.hashentry_bytes; 779 780 _counts[RO][SymbolBucketType] = stats->symbol.bucket_count; 781 _bytes [RO][SymbolBucketType] = stats->symbol.bucket_bytes; 782 783 // strings 784 _counts[RO][StringHashentryType] = stats->string.hashentry_count; 785 _bytes [RO][StringHashentryType] = stats->string.hashentry_bytes; 786 787 _counts[RO][StringBucketType] = stats->string.bucket_count; 788 _bytes [RO][StringBucketType] = stats->string.bucket_bytes; 789 790 // TODO: count things like dictionary, vtable, etc 791 _bytes[RW][OtherType] += mc_all + md_all; 792 rw_all += mc_all + md_all; // mc/md are mapped Read/Write 793 794 // prevent divide-by-zero 795 if (ro_all < 1) { 796 ro_all = 1; 797 } 798 if (rw_all < 1) { 799 rw_all = 1; 800 } 801 802 int all_ro_count = 0; 803 int all_ro_bytes = 0; 804 int all_rw_count = 0; 805 int all_rw_bytes = 0; 806 807 // To make fmt_stats be a syntactic constant (for format warnings), use #define. 808 #define fmt_stats "%-20s: %8d %10d %5.1f | %8d %10d %5.1f | %8d %10d %5.1f" 809 const char *sep = "--------------------+---------------------------+---------------------------+--------------------------"; 810 const char *hdr = " ro_cnt ro_bytes % | rw_cnt rw_bytes % | all_cnt all_bytes %"; 811 812 ResourceMark rm; 813 LogMessage(cds) msg; 814 stringStream info_stream; 815 816 info_stream.print_cr("Detailed metadata info (excluding od/st regions; rw stats include md/mc regions):"); 817 info_stream.print_cr("%s", hdr); 818 info_stream.print_cr("%s", sep); 819 for (int type = 0; type < int(_number_of_types); type ++) { 820 const char *name = type_name((Type)type); 821 int ro_count = _counts[RO][type]; 822 int ro_bytes = _bytes [RO][type]; 823 int rw_count = _counts[RW][type]; 824 int rw_bytes = _bytes [RW][type]; 825 int count = ro_count + rw_count; 826 int bytes = ro_bytes + rw_bytes; 827 828 double ro_perc = 100.0 * double(ro_bytes) / double(ro_all); 829 double rw_perc = 100.0 * double(rw_bytes) / double(rw_all); 830 double perc = 100.0 * double(bytes) / double(ro_all + rw_all); 831 832 info_stream.print_cr(fmt_stats, name, 833 ro_count, ro_bytes, ro_perc, 834 rw_count, rw_bytes, rw_perc, 835 count, bytes, perc); 836 837 all_ro_count += ro_count; 838 all_ro_bytes += ro_bytes; 839 all_rw_count += rw_count; 840 all_rw_bytes += rw_bytes; 841 } 842 843 int all_count = all_ro_count + all_rw_count; 844 int all_bytes = all_ro_bytes + all_rw_bytes; 845 846 double all_ro_perc = 100.0 * double(all_ro_bytes) / double(ro_all); 847 double all_rw_perc = 100.0 * double(all_rw_bytes) / double(rw_all); 848 double all_perc = 100.0 * double(all_bytes) / double(ro_all + rw_all); 849 850 info_stream.print_cr("%s", sep); 851 info_stream.print_cr(fmt_stats, "Total", 852 all_ro_count, all_ro_bytes, all_ro_perc, 853 all_rw_count, all_rw_bytes, all_rw_perc, 854 all_count, all_bytes, all_perc); 855 856 assert(all_ro_bytes == ro_all, "everything should have been counted"); 857 assert(all_rw_bytes == rw_all, "everything should have been counted"); 858 859 msg.info("%s", info_stream.as_string()); 860 #undef fmt_stats 861 } 862 863 // Populate the shared space. 864 865 class VM_PopulateDumpSharedSpace: public VM_Operation { 866 private: 867 GrowableArray<MemRegion> *_string_regions; 868 GrowableArray<MemRegion> *_open_archive_heap_regions; 869 870 void dump_java_heap_objects() NOT_CDS_JAVA_HEAP_RETURN; 871 void dump_symbols(); 872 char* dump_read_only_tables(); 873 void print_region_stats(); 874 void print_heap_region_stats(GrowableArray<MemRegion> *heap_mem, 875 const char *name, const size_t total_size); 876 public: 877 878 VMOp_Type type() const { return VMOp_PopulateDumpSharedSpace; } 879 void doit(); // outline because gdb sucks 880 static void write_region(FileMapInfo* mapinfo, int region, DumpRegion* space, bool read_only, bool allow_exec); 881 }; // class VM_PopulateDumpSharedSpace 882 883 class SortedSymbolClosure: public SymbolClosure { 884 GrowableArray<Symbol*> _symbols; 885 virtual void do_symbol(Symbol** sym) { 886 assert((*sym)->is_permanent(), "archived symbols must be permanent"); 887 _symbols.append(*sym); 888 } 889 static int compare_symbols_by_address(Symbol** a, Symbol** b) { 890 if (a[0] < b[0]) { 891 return -1; 892 } else if (a[0] == b[0]) { 893 return 0; 894 } else { 895 return 1; 896 } 897 } 898 899 public: 900 SortedSymbolClosure() { 901 SymbolTable::symbols_do(this); 902 _symbols.sort(compare_symbols_by_address); 903 } 904 GrowableArray<Symbol*>* get_sorted_symbols() { 905 return &_symbols; 906 } 907 }; 908 909 // ArchiveCompactor -- 910 // 911 // This class is the central piece of shared archive compaction -- all metaspace data are 912 // initially allocated outside of the shared regions. ArchiveCompactor copies the 913 // metaspace data into their final location in the shared regions. 914 915 class ArchiveCompactor : AllStatic { 916 static DumpAllocStats* _alloc_stats; 917 static SortedSymbolClosure* _ssc; 918 919 static unsigned my_hash(const address& a) { 920 return primitive_hash<address>(a); 921 } 922 static bool my_equals(const address& a0, const address& a1) { 923 return primitive_equals<address>(a0, a1); 924 } 925 typedef ResourceHashtable< 926 address, address, 927 ArchiveCompactor::my_hash, // solaris compiler doesn't like: primitive_hash<address> 928 ArchiveCompactor::my_equals, // solaris compiler doesn't like: primitive_equals<address> 929 16384, ResourceObj::C_HEAP> RelocationTable; 930 static RelocationTable* _new_loc_table; 931 932 public: 933 static void initialize() { 934 _alloc_stats = new(ResourceObj::C_HEAP, mtInternal)DumpAllocStats; 935 _new_loc_table = new(ResourceObj::C_HEAP, mtInternal)RelocationTable; 936 } 937 static DumpAllocStats* alloc_stats() { 938 return _alloc_stats; 939 } 940 941 static void allocate(MetaspaceClosure::Ref* ref, bool read_only) { 942 address obj = ref->obj(); 943 int bytes = ref->size() * BytesPerWord; 944 char* p; 945 size_t alignment = BytesPerWord; 946 char* oldtop; 947 char* newtop; 948 949 if (read_only) { 950 oldtop = _ro_region.top(); 951 p = _ro_region.allocate(bytes, alignment); 952 newtop = _ro_region.top(); 953 } else { 954 oldtop = _rw_region.top(); 955 p = _rw_region.allocate(bytes, alignment); 956 newtop = _rw_region.top(); 957 } 958 memcpy(p, obj, bytes); 959 bool isnew = _new_loc_table->put(obj, (address)p); 960 assert(isnew, "must be"); 961 log_trace(cds)("Copy: " PTR_FORMAT " ==> " PTR_FORMAT " %d", p2i(obj), p2i(p), bytes); 962 963 _alloc_stats->record(ref->msotype(), int(newtop - oldtop), read_only); 964 if (ref->msotype() == MetaspaceObj::SymbolType) { 965 uintx delta = MetaspaceShared::object_delta(p); 966 if (delta > MAX_SHARED_DELTA) { 967 // This is just a sanity check and should not appear in any real world usage. This 968 // happens only if you allocate more than 2GB of Symbols and would require 969 // millions of shared classes. 970 vm_exit_during_initialization("Too many Symbols in the CDS archive", 971 "Please reduce the number of shared classes."); 972 } 973 } 974 } 975 976 static address get_new_loc(MetaspaceClosure::Ref* ref) { 977 address* pp = _new_loc_table->get(ref->obj()); 978 assert(pp != NULL, "must be"); 979 return *pp; 980 } 981 982 private: 983 // Makes a shallow copy of visited MetaspaceObj's 984 class ShallowCopier: public UniqueMetaspaceClosure { 985 bool _read_only; 986 public: 987 ShallowCopier(bool read_only) : _read_only(read_only) {} 988 989 virtual void do_unique_ref(Ref* ref, bool read_only) { 990 if (read_only == _read_only) { 991 allocate(ref, read_only); 992 } 993 } 994 }; 995 996 // Relocate embedded pointers within a MetaspaceObj's shallow copy 997 class ShallowCopyEmbeddedRefRelocator: public UniqueMetaspaceClosure { 998 public: 999 virtual void do_unique_ref(Ref* ref, bool read_only) { 1000 address new_loc = get_new_loc(ref); 1001 RefRelocator refer; 1002 ref->metaspace_pointers_do_at(&refer, new_loc); 1003 } 1004 }; 1005 1006 // Relocate a reference to point to its shallow copy 1007 class RefRelocator: public MetaspaceClosure { 1008 public: 1009 virtual bool do_ref(Ref* ref, bool read_only) { 1010 if (ref->not_null()) { 1011 ref->update(get_new_loc(ref)); 1012 } 1013 return false; // Do not recurse. 1014 } 1015 }; 1016 1017 #ifdef ASSERT 1018 class IsRefInArchiveChecker: public MetaspaceClosure { 1019 public: 1020 virtual bool do_ref(Ref* ref, bool read_only) { 1021 if (ref->not_null()) { 1022 char* obj = (char*)ref->obj(); 1023 assert(_ro_region.contains(obj) || _rw_region.contains(obj), 1024 "must be relocated to point to CDS archive"); 1025 } 1026 return false; // Do not recurse. 1027 } 1028 }; 1029 #endif 1030 1031 public: 1032 static void copy_and_compact() { 1033 // We should no longer allocate anything from the metaspace, so that 1034 // we can have a stable set of MetaspaceObjs to work with. 1035 Metaspace::freeze(); 1036 1037 ResourceMark rm; 1038 SortedSymbolClosure the_ssc; // StackObj 1039 _ssc = &the_ssc; 1040 1041 tty->print_cr("Scanning all metaspace objects ... "); 1042 { 1043 // allocate and shallow-copy RW objects, immediately following the MC region 1044 tty->print_cr("Allocating RW objects ... "); 1045 _mc_region.pack(&_rw_region); 1046 1047 ResourceMark rm; 1048 ShallowCopier rw_copier(false); 1049 iterate_roots(&rw_copier); 1050 } 1051 { 1052 // allocate and shallow-copy of RO object, immediately following the RW region 1053 tty->print_cr("Allocating RO objects ... "); 1054 _rw_region.pack(&_ro_region); 1055 1056 ResourceMark rm; 1057 ShallowCopier ro_copier(true); 1058 iterate_roots(&ro_copier); 1059 } 1060 { 1061 tty->print_cr("Relocating embedded pointers ... "); 1062 ResourceMark rm; 1063 ShallowCopyEmbeddedRefRelocator emb_reloc; 1064 iterate_roots(&emb_reloc); 1065 } 1066 { 1067 tty->print_cr("Relocating external roots ... "); 1068 ResourceMark rm; 1069 RefRelocator ext_reloc; 1070 iterate_roots(&ext_reloc); 1071 } 1072 1073 #ifdef ASSERT 1074 { 1075 tty->print_cr("Verifying external roots ... "); 1076 ResourceMark rm; 1077 IsRefInArchiveChecker checker; 1078 iterate_roots(&checker); 1079 } 1080 #endif 1081 1082 1083 // cleanup 1084 _ssc = NULL; 1085 } 1086 1087 // We must relocate the System::_well_known_klasses only after we have copied the 1088 // java objects in during dump_java_heap_objects(): during the object copy, we operate on 1089 // old objects which assert that their klass is the original klass. 1090 static void relocate_well_known_klasses() { 1091 { 1092 tty->print_cr("Relocating SystemDictionary::_well_known_klasses[] ... "); 1093 ResourceMark rm; 1094 RefRelocator ext_reloc; 1095 SystemDictionary::well_known_klasses_do(&ext_reloc); 1096 } 1097 // NOTE: after this point, we shouldn't have any globals that can reach the old 1098 // objects. 1099 1100 // We cannot use any of the objects in the heap anymore (except for the objects 1101 // in the CDS shared string regions) because their headers no longer point to 1102 // valid Klasses. 1103 } 1104 1105 static void iterate_roots(MetaspaceClosure* it) { 1106 GrowableArray<Symbol*>* symbols = _ssc->get_sorted_symbols(); 1107 for (int i=0; i<symbols->length(); i++) { 1108 it->push(symbols->adr_at(i)); 1109 } 1110 if (_global_klass_objects != NULL) { 1111 // Need to fix up the pointers 1112 for (int i = 0; i < _global_klass_objects->length(); i++) { 1113 // NOTE -- this requires that the vtable is NOT yet patched, or else we are hosed. 1114 it->push(_global_klass_objects->adr_at(i)); 1115 } 1116 } 1117 FileMapInfo::metaspace_pointers_do(it); 1118 SystemDictionary::classes_do(it); 1119 Universe::metaspace_pointers_do(it); 1120 SymbolTable::metaspace_pointers_do(it); 1121 vmSymbols::metaspace_pointers_do(it); 1122 } 1123 1124 static Klass* get_relocated_klass(Klass* orig_klass) { 1125 address* pp = _new_loc_table->get((address)orig_klass); 1126 assert(pp != NULL, "must be"); 1127 Klass* klass = (Klass*)(*pp); 1128 assert(klass->is_klass(), "must be"); 1129 return klass; 1130 } 1131 }; 1132 1133 DumpAllocStats* ArchiveCompactor::_alloc_stats; 1134 SortedSymbolClosure* ArchiveCompactor::_ssc; 1135 ArchiveCompactor::RelocationTable* ArchiveCompactor::_new_loc_table; 1136 1137 void VM_PopulateDumpSharedSpace::write_region(FileMapInfo* mapinfo, int region_idx, 1138 DumpRegion* dump_region, bool read_only, bool allow_exec) { 1139 mapinfo->write_region(region_idx, dump_region->base(), dump_region->used(), read_only, allow_exec); 1140 } 1141 1142 void VM_PopulateDumpSharedSpace::dump_symbols() { 1143 tty->print_cr("Dumping symbol table ..."); 1144 1145 NOT_PRODUCT(SymbolTable::verify()); 1146 SymbolTable::write_to_archive(); 1147 } 1148 1149 char* VM_PopulateDumpSharedSpace::dump_read_only_tables() { 1150 char* oldtop = _ro_region.top(); 1151 // Reorder the system dictionary. Moving the symbols affects 1152 // how the hash table indices are calculated. 1153 SystemDictionary::reorder_dictionary_for_sharing(); 1154 NOT_PRODUCT(SystemDictionary::verify();) 1155 1156 size_t buckets_bytes = SystemDictionary::count_bytes_for_buckets(); 1157 char* buckets_top = _ro_region.allocate(buckets_bytes, sizeof(intptr_t)); 1158 SystemDictionary::copy_buckets(buckets_top, _ro_region.top()); 1159 1160 size_t table_bytes = SystemDictionary::count_bytes_for_table(); 1161 char* table_top = _ro_region.allocate(table_bytes, sizeof(intptr_t)); 1162 SystemDictionary::copy_table(table_top, _ro_region.top()); 1163 1164 // Write the other data to the output array. 1165 WriteClosure wc(&_ro_region); 1166 MetaspaceShared::serialize(&wc); 1167 1168 char* newtop = _ro_region.top(); 1169 ArchiveCompactor::alloc_stats()->record_other_type(int(newtop - oldtop), true); 1170 return buckets_top; 1171 } 1172 1173 void VM_PopulateDumpSharedSpace::doit() { 1174 Thread* THREAD = VMThread::vm_thread(); 1175 1176 NOT_PRODUCT(SystemDictionary::verify();) 1177 // The following guarantee is meant to ensure that no loader constraints 1178 // exist yet, since the constraints table is not shared. This becomes 1179 // more important now that we don't re-initialize vtables/itables for 1180 // shared classes at runtime, where constraints were previously created. 1181 guarantee(SystemDictionary::constraints()->number_of_entries() == 0, 1182 "loader constraints are not saved"); 1183 guarantee(SystemDictionary::placeholders()->number_of_entries() == 0, 1184 "placeholders are not saved"); 1185 // Revisit and implement this if we prelink method handle call sites: 1186 guarantee(SystemDictionary::invoke_method_table() == NULL || 1187 SystemDictionary::invoke_method_table()->number_of_entries() == 0, 1188 "invoke method table is not saved"); 1189 1190 // At this point, many classes have been loaded. 1191 // Gather systemDictionary classes in a global array and do everything to 1192 // that so we don't have to walk the SystemDictionary again. 1193 _global_klass_objects = new GrowableArray<Klass*>(1000); 1194 CollectClassesClosure collect_classes; 1195 ClassLoaderDataGraph::loaded_classes_do(&collect_classes); 1196 1197 tty->print_cr("Number of classes %d", _global_klass_objects->length()); 1198 { 1199 int num_type_array = 0, num_obj_array = 0, num_inst = 0; 1200 for (int i = 0; i < _global_klass_objects->length(); i++) { 1201 Klass* k = _global_klass_objects->at(i); 1202 if (k->is_instance_klass()) { 1203 num_inst ++; 1204 } else if (k->is_objArray_klass()) { 1205 num_obj_array ++; 1206 } else { 1207 assert(k->is_typeArray_klass(), "sanity"); 1208 num_type_array ++; 1209 } 1210 } 1211 tty->print_cr(" instance classes = %5d", num_inst); 1212 tty->print_cr(" obj array classes = %5d", num_obj_array); 1213 tty->print_cr(" type array classes = %5d", num_type_array); 1214 } 1215 1216 // Ensure the ConstMethods won't be modified at run-time 1217 tty->print("Updating ConstMethods ... "); 1218 rewrite_nofast_bytecodes_and_calculate_fingerprints(); 1219 tty->print_cr("done. "); 1220 1221 // Remove all references outside the metadata 1222 tty->print("Removing unshareable information ... "); 1223 remove_unshareable_in_classes(); 1224 tty->print_cr("done. "); 1225 1226 ArchiveCompactor::initialize(); 1227 ArchiveCompactor::copy_and_compact(); 1228 1229 dump_symbols(); 1230 1231 // Dump supported java heap objects 1232 _string_regions = NULL; 1233 _open_archive_heap_regions = NULL; 1234 dump_java_heap_objects(); 1235 1236 ArchiveCompactor::relocate_well_known_klasses(); 1237 1238 char* read_only_tables_start = dump_read_only_tables(); 1239 _ro_region.pack(&_md_region); 1240 1241 char* vtbl_list = _md_region.top(); 1242 MetaspaceShared::allocate_cpp_vtable_clones(); 1243 _md_region.pack(&_od_region); 1244 1245 // Relocate the archived class file data into the od region 1246 relocate_cached_class_file(); 1247 _od_region.pack(); 1248 1249 // The 5 core spaces are allocated consecutively mc->rw->ro->md->od, so there total size 1250 // is just the spaces between the two ends. 1251 size_t core_spaces_size = _od_region.end() - _mc_region.base(); 1252 assert(core_spaces_size == (size_t)align_up(core_spaces_size, Metaspace::reserve_alignment()), 1253 "should already be aligned"); 1254 1255 // During patching, some virtual methods may be called, so at this point 1256 // the vtables must contain valid methods (as filled in by CppVtableCloner::allocate). 1257 MetaspaceShared::patch_cpp_vtable_pointers(); 1258 1259 // The vtable clones contain addresses of the current process. 1260 // We don't want to write these addresses into the archive. 1261 MetaspaceShared::zero_cpp_vtable_clones_for_writing(); 1262 1263 // Create and write the archive file that maps the shared spaces. 1264 1265 FileMapInfo* mapinfo = new FileMapInfo(); 1266 mapinfo->populate_header(os::vm_allocation_granularity()); 1267 mapinfo->set_read_only_tables_start(read_only_tables_start); 1268 mapinfo->set_misc_data_patching_start(vtbl_list); 1269 mapinfo->set_cds_i2i_entry_code_buffers(MetaspaceShared::cds_i2i_entry_code_buffers()); 1270 mapinfo->set_cds_i2i_entry_code_buffers_size(MetaspaceShared::cds_i2i_entry_code_buffers_size()); 1271 mapinfo->set_core_spaces_size(core_spaces_size); 1272 1273 for (int pass=1; pass<=2; pass++) { 1274 if (pass == 1) { 1275 // The first pass doesn't actually write the data to disk. All it 1276 // does is to update the fields in the mapinfo->_header. 1277 } else { 1278 // After the first pass, the contents of mapinfo->_header are finalized, 1279 // so we can compute the header's CRC, and write the contents of the header 1280 // and the regions into disk. 1281 mapinfo->open_for_write(); 1282 mapinfo->set_header_crc(mapinfo->compute_header_crc()); 1283 } 1284 mapinfo->write_header(); 1285 1286 // NOTE: md contains the trampoline code for method entries, which are patched at run time, 1287 // so it needs to be read/write. 1288 write_region(mapinfo, MetaspaceShared::mc, &_mc_region, /*read_only=*/false,/*allow_exec=*/true); 1289 write_region(mapinfo, MetaspaceShared::rw, &_rw_region, /*read_only=*/false,/*allow_exec=*/false); 1290 write_region(mapinfo, MetaspaceShared::ro, &_ro_region, /*read_only=*/true, /*allow_exec=*/false); 1291 write_region(mapinfo, MetaspaceShared::md, &_md_region, /*read_only=*/false,/*allow_exec=*/false); 1292 write_region(mapinfo, MetaspaceShared::od, &_od_region, /*read_only=*/true, /*allow_exec=*/false); 1293 1294 _total_string_region_size = mapinfo->write_archive_heap_regions( 1295 _string_regions, 1296 MetaspaceShared::first_string, 1297 MetaspaceShared::max_strings); 1298 _total_open_archive_region_size = mapinfo->write_archive_heap_regions( 1299 _open_archive_heap_regions, 1300 MetaspaceShared::first_open_archive_heap_region, 1301 MetaspaceShared::max_open_archive_heap_region); 1302 } 1303 1304 mapinfo->close(); 1305 1306 // Restore the vtable in case we invoke any virtual methods. 1307 MetaspaceShared::clone_cpp_vtables((intptr_t*)vtbl_list); 1308 1309 print_region_stats(); 1310 1311 if (log_is_enabled(Info, cds)) { 1312 ArchiveCompactor::alloc_stats()->print_stats(int(_ro_region.used()), int(_rw_region.used()), 1313 int(_mc_region.used()), int(_md_region.used())); 1314 } 1315 } 1316 1317 void VM_PopulateDumpSharedSpace::print_region_stats() { 1318 // Print statistics of all the regions 1319 const size_t total_reserved = _ro_region.reserved() + _rw_region.reserved() + 1320 _mc_region.reserved() + _md_region.reserved() + 1321 _od_region.reserved() + 1322 _total_string_region_size + 1323 _total_open_archive_region_size; 1324 const size_t total_bytes = _ro_region.used() + _rw_region.used() + 1325 _mc_region.used() + _md_region.used() + 1326 _od_region.used() + 1327 _total_string_region_size + 1328 _total_open_archive_region_size; 1329 const double total_u_perc = total_bytes / double(total_reserved) * 100.0; 1330 1331 _mc_region.print(total_reserved); 1332 _rw_region.print(total_reserved); 1333 _ro_region.print(total_reserved); 1334 _md_region.print(total_reserved); 1335 _od_region.print(total_reserved); 1336 print_heap_region_stats(_string_regions, "st", total_reserved); 1337 print_heap_region_stats(_open_archive_heap_regions, "oa", total_reserved); 1338 1339 tty->print_cr("total : " SIZE_FORMAT_W(9) " [100.0%% of total] out of " SIZE_FORMAT_W(9) " bytes [%5.1f%% used]", 1340 total_bytes, total_reserved, total_u_perc); 1341 } 1342 1343 void VM_PopulateDumpSharedSpace::print_heap_region_stats(GrowableArray<MemRegion> *heap_mem, 1344 const char *name, const size_t total_size) { 1345 int arr_len = heap_mem == NULL ? 0 : heap_mem->length(); 1346 for (int i = 0; i < arr_len; i++) { 1347 char* start = (char*)heap_mem->at(i).start(); 1348 size_t size = heap_mem->at(i).byte_size(); 1349 char* top = start + size; 1350 tty->print_cr("%s%d space: " SIZE_FORMAT_W(9) " [ %4.1f%% of total] out of " SIZE_FORMAT_W(9) " bytes [100%% used] at " INTPTR_FORMAT, 1351 name, i, size, size/double(total_size)*100.0, size, p2i(start)); 1352 1353 } 1354 } 1355 1356 // Update a Java object to point its Klass* to the new location after 1357 // shared archive has been compacted. 1358 void MetaspaceShared::relocate_klass_ptr(oop o) { 1359 assert(DumpSharedSpaces, "sanity"); 1360 Klass* k = ArchiveCompactor::get_relocated_klass(o->klass()); 1361 o->set_klass(k); 1362 } 1363 1364 class LinkSharedClassesClosure : public KlassClosure { 1365 Thread* THREAD; 1366 bool _made_progress; 1367 public: 1368 LinkSharedClassesClosure(Thread* thread) : THREAD(thread), _made_progress(false) {} 1369 1370 void reset() { _made_progress = false; } 1371 bool made_progress() const { return _made_progress; } 1372 1373 void do_klass(Klass* k) { 1374 if (k->is_instance_klass()) { 1375 InstanceKlass* ik = InstanceKlass::cast(k); 1376 // Link the class to cause the bytecodes to be rewritten and the 1377 // cpcache to be created. Class verification is done according 1378 // to -Xverify setting. 1379 _made_progress |= MetaspaceShared::try_link_class(ik, THREAD); 1380 guarantee(!HAS_PENDING_EXCEPTION, "exception in link_class"); 1381 1382 ik->constants()->resolve_class_constants(THREAD); 1383 } 1384 } 1385 }; 1386 1387 class CheckSharedClassesClosure : public KlassClosure { 1388 bool _made_progress; 1389 public: 1390 CheckSharedClassesClosure() : _made_progress(false) {} 1391 1392 void reset() { _made_progress = false; } 1393 bool made_progress() const { return _made_progress; } 1394 void do_klass(Klass* k) { 1395 if (k->is_instance_klass() && InstanceKlass::cast(k)->check_sharing_error_state()) { 1396 _made_progress = true; 1397 } 1398 } 1399 }; 1400 1401 void MetaspaceShared::check_shared_class_loader_type(Klass* k) { 1402 if (k->is_instance_klass()) { 1403 InstanceKlass* ik = InstanceKlass::cast(k); 1404 u2 loader_type = ik->loader_type(); 1405 ResourceMark rm; 1406 guarantee(loader_type != 0, 1407 "Class loader type is not set for this class %s", ik->name()->as_C_string()); 1408 } 1409 } 1410 1411 void MetaspaceShared::link_and_cleanup_shared_classes(TRAPS) { 1412 // We need to iterate because verification may cause additional classes 1413 // to be loaded. 1414 LinkSharedClassesClosure link_closure(THREAD); 1415 do { 1416 link_closure.reset(); 1417 ClassLoaderDataGraph::loaded_classes_do(&link_closure); 1418 guarantee(!HAS_PENDING_EXCEPTION, "exception in link_class"); 1419 } while (link_closure.made_progress()); 1420 1421 if (_has_error_classes) { 1422 // Mark all classes whose super class or interfaces failed verification. 1423 CheckSharedClassesClosure check_closure; 1424 do { 1425 // Not completely sure if we need to do this iteratively. Anyway, 1426 // we should come here only if there are unverifiable classes, which 1427 // shouldn't happen in normal cases. So better safe than sorry. 1428 check_closure.reset(); 1429 ClassLoaderDataGraph::loaded_classes_do(&check_closure); 1430 } while (check_closure.made_progress()); 1431 1432 if (IgnoreUnverifiableClassesDuringDump) { 1433 // This is useful when running JCK or SQE tests. You should not 1434 // enable this when running real apps. 1435 SystemDictionary::remove_classes_in_error_state(); 1436 } else { 1437 tty->print_cr("Please remove the unverifiable classes from your class list and try again"); 1438 exit(1); 1439 } 1440 } 1441 1442 // Copy the verification constraints from C_HEAP-alloced GrowableArrays to RO-alloced 1443 // Arrays 1444 SystemDictionaryShared::finalize_verification_constraints(); 1445 } 1446 1447 void MetaspaceShared::prepare_for_dumping() { 1448 Arguments::check_unsupported_dumping_properties(); 1449 ClassLoader::initialize_shared_path(); 1450 FileMapInfo::allocate_classpath_entry_table(); 1451 } 1452 1453 // Preload classes from a list, populate the shared spaces and dump to a 1454 // file. 1455 void MetaspaceShared::preload_and_dump(TRAPS) { 1456 { TraceTime timer("Dump Shared Spaces", TRACETIME_LOG(Info, startuptime)); 1457 ResourceMark rm; 1458 char class_list_path_str[JVM_MAXPATHLEN]; 1459 // Preload classes to be shared. 1460 // Should use some os:: method rather than fopen() here. aB. 1461 const char* class_list_path; 1462 if (SharedClassListFile == NULL) { 1463 // Construct the path to the class list (in jre/lib) 1464 // Walk up two directories from the location of the VM and 1465 // optionally tack on "lib" (depending on platform) 1466 os::jvm_path(class_list_path_str, sizeof(class_list_path_str)); 1467 for (int i = 0; i < 3; i++) { 1468 char *end = strrchr(class_list_path_str, *os::file_separator()); 1469 if (end != NULL) *end = '\0'; 1470 } 1471 int class_list_path_len = (int)strlen(class_list_path_str); 1472 if (class_list_path_len >= 3) { 1473 if (strcmp(class_list_path_str + class_list_path_len - 3, "lib") != 0) { 1474 if (class_list_path_len < JVM_MAXPATHLEN - 4) { 1475 jio_snprintf(class_list_path_str + class_list_path_len, 1476 sizeof(class_list_path_str) - class_list_path_len, 1477 "%slib", os::file_separator()); 1478 class_list_path_len += 4; 1479 } 1480 } 1481 } 1482 if (class_list_path_len < JVM_MAXPATHLEN - 10) { 1483 jio_snprintf(class_list_path_str + class_list_path_len, 1484 sizeof(class_list_path_str) - class_list_path_len, 1485 "%sclasslist", os::file_separator()); 1486 } 1487 class_list_path = class_list_path_str; 1488 } else { 1489 class_list_path = SharedClassListFile; 1490 } 1491 1492 tty->print_cr("Loading classes to share ..."); 1493 _has_error_classes = false; 1494 int class_count = preload_classes(class_list_path, THREAD); 1495 if (ExtraSharedClassListFile) { 1496 class_count += preload_classes(ExtraSharedClassListFile, THREAD); 1497 } 1498 tty->print_cr("Loading classes to share: done."); 1499 1500 log_info(cds)("Shared spaces: preloaded %d classes", class_count); 1501 1502 // Rewrite and link classes 1503 tty->print_cr("Rewriting and linking classes ..."); 1504 1505 // Link any classes which got missed. This would happen if we have loaded classes that 1506 // were not explicitly specified in the classlist. E.g., if an interface implemented by class K 1507 // fails verification, all other interfaces that were not specified in the classlist but 1508 // are implemented by K are not verified. 1509 link_and_cleanup_shared_classes(CATCH); 1510 tty->print_cr("Rewriting and linking classes: done"); 1511 1512 VM_PopulateDumpSharedSpace op; 1513 VMThread::execute(&op); 1514 } 1515 1516 if (PrintSystemDictionaryAtExit) { 1517 SystemDictionary::print(); 1518 } 1519 1520 // Since various initialization steps have been undone by this process, 1521 // it is not reasonable to continue running a java process. 1522 exit(0); 1523 } 1524 1525 1526 int MetaspaceShared::preload_classes(const char* class_list_path, TRAPS) { 1527 ClassListParser parser(class_list_path); 1528 int class_count = 0; 1529 1530 while (parser.parse_one_line()) { 1531 Klass* klass = ClassLoaderExt::load_one_class(&parser, THREAD); 1532 1533 CLEAR_PENDING_EXCEPTION; 1534 if (klass != NULL) { 1535 if (log_is_enabled(Trace, cds)) { 1536 ResourceMark rm; 1537 log_trace(cds)("Shared spaces preloaded: %s", klass->external_name()); 1538 } 1539 1540 InstanceKlass* ik = InstanceKlass::cast(klass); 1541 1542 // Link the class to cause the bytecodes to be rewritten and the 1543 // cpcache to be created. The linking is done as soon as classes 1544 // are loaded in order that the related data structures (klass and 1545 // cpCache) are located together. 1546 try_link_class(ik, THREAD); 1547 guarantee(!HAS_PENDING_EXCEPTION, "exception in link_class"); 1548 1549 class_count++; 1550 } 1551 } 1552 1553 return class_count; 1554 } 1555 1556 // Returns true if the class's status has changed 1557 bool MetaspaceShared::try_link_class(InstanceKlass* ik, TRAPS) { 1558 assert(DumpSharedSpaces, "should only be called during dumping"); 1559 if (ik->init_state() < InstanceKlass::linked) { 1560 bool saved = BytecodeVerificationLocal; 1561 if (!(ik->is_shared_boot_class())) { 1562 // The verification decision is based on BytecodeVerificationRemote 1563 // for non-system classes. Since we are using the NULL classloader 1564 // to load non-system classes during dumping, we need to temporarily 1565 // change BytecodeVerificationLocal to be the same as 1566 // BytecodeVerificationRemote. Note this can cause the parent system 1567 // classes also being verified. The extra overhead is acceptable during 1568 // dumping. 1569 BytecodeVerificationLocal = BytecodeVerificationRemote; 1570 } 1571 ik->link_class(THREAD); 1572 if (HAS_PENDING_EXCEPTION) { 1573 ResourceMark rm; 1574 tty->print_cr("Preload Warning: Verification failed for %s", 1575 ik->external_name()); 1576 CLEAR_PENDING_EXCEPTION; 1577 ik->set_in_error_state(); 1578 _has_error_classes = true; 1579 } 1580 BytecodeVerificationLocal = saved; 1581 return true; 1582 } else { 1583 return false; 1584 } 1585 } 1586 1587 #if INCLUDE_CDS_JAVA_HEAP 1588 void VM_PopulateDumpSharedSpace::dump_java_heap_objects() { 1589 if (!MetaspaceShared::is_heap_object_archiving_allowed()) { 1590 if (log_is_enabled(Info, cds)) { 1591 log_info(cds)( 1592 "Archived java heap is not supported as UseG1GC, " 1593 "UseCompressedOops and UseCompressedClassPointers are required." 1594 "Current settings: UseG1GC=%s, UseCompressedOops=%s, UseCompressedClassPointers=%s.", 1595 BOOL_TO_STR(UseG1GC), BOOL_TO_STR(UseCompressedOops), 1596 BOOL_TO_STR(UseCompressedClassPointers)); 1597 } 1598 return; 1599 } 1600 1601 NoSafepointVerifier nsv; 1602 1603 // Cache for recording where the archived objects are copied to 1604 MetaspaceShared::create_archive_object_cache(); 1605 1606 tty->print_cr("Dumping String objects to closed archive heap region ..."); 1607 NOT_PRODUCT(StringTable::verify()); 1608 // The string space has maximum two regions. See FileMapInfo::write_archive_heap_regions() for details. 1609 _string_regions = new GrowableArray<MemRegion>(2); 1610 StringTable::write_to_archive(_string_regions); 1611 1612 tty->print_cr("Dumping objects to open archive heap region ..."); 1613 _open_archive_heap_regions = new GrowableArray<MemRegion>(2); 1614 MetaspaceShared::dump_open_archive_heap_objects(_open_archive_heap_regions); 1615 } 1616 1617 void MetaspaceShared::dump_open_archive_heap_objects( 1618 GrowableArray<MemRegion> * open_archive) { 1619 assert(UseG1GC, "Only support G1 GC"); 1620 assert(UseCompressedOops && UseCompressedClassPointers, 1621 "Only support UseCompressedOops and UseCompressedClassPointers enabled"); 1622 1623 Thread* THREAD = Thread::current(); 1624 G1CollectedHeap::heap()->begin_archive_alloc_range(true /* open */); 1625 1626 MetaspaceShared::archive_resolved_constants(THREAD); 1627 1628 G1CollectedHeap::heap()->end_archive_alloc_range(open_archive, 1629 os::vm_allocation_granularity()); 1630 } 1631 1632 MetaspaceShared::ArchivedObjectCache* MetaspaceShared::_archive_object_cache = NULL; 1633 oop MetaspaceShared::archive_heap_object(oop obj, Thread* THREAD) { 1634 assert(DumpSharedSpaces, "dump-time only"); 1635 1636 ArchivedObjectCache* cache = MetaspaceShared::archive_object_cache(); 1637 oop* p = cache->get(obj); 1638 if (p != NULL) { 1639 // already archived 1640 return *p; 1641 } 1642 1643 int len = obj->size(); 1644 if (G1CollectedHeap::heap()->is_archive_alloc_too_large(len)) { 1645 return NULL; 1646 } 1647 1648 int hash = obj->identity_hash(); 1649 oop archived_oop = (oop)G1CollectedHeap::heap()->archive_mem_allocate(len); 1650 if (archived_oop != NULL) { 1651 Copy::aligned_disjoint_words((HeapWord*)obj, (HeapWord*)archived_oop, len); 1652 relocate_klass_ptr(archived_oop); 1653 cache->put(obj, archived_oop); 1654 } 1655 return archived_oop; 1656 } 1657 1658 void MetaspaceShared::archive_resolved_constants(Thread* THREAD) { 1659 int i; 1660 for (i = 0; i < _global_klass_objects->length(); i++) { 1661 Klass* k = _global_klass_objects->at(i); 1662 if (k->is_instance_klass()) { 1663 InstanceKlass* ik = InstanceKlass::cast(k); 1664 ik->constants()->archive_resolved_references(THREAD); 1665 } 1666 } 1667 } 1668 1669 void MetaspaceShared::fixup_mapped_heap_regions() { 1670 FileMapInfo *mapinfo = FileMapInfo::current_info(); 1671 mapinfo->fixup_mapped_heap_regions(); 1672 } 1673 #endif // INCLUDE_CDS_JAVA_HEAP 1674 1675 // Closure for serializing initialization data in from a data area 1676 // (ptr_array) read from the shared file. 1677 1678 class ReadClosure : public SerializeClosure { 1679 private: 1680 intptr_t** _ptr_array; 1681 1682 inline intptr_t nextPtr() { 1683 return *(*_ptr_array)++; 1684 } 1685 1686 public: 1687 ReadClosure(intptr_t** ptr_array) { _ptr_array = ptr_array; } 1688 1689 void do_ptr(void** p) { 1690 assert(*p == NULL, "initializing previous initialized pointer."); 1691 intptr_t obj = nextPtr(); 1692 assert((intptr_t)obj >= 0 || (intptr_t)obj < -100, 1693 "hit tag while initializing ptrs."); 1694 *p = (void*)obj; 1695 } 1696 1697 void do_u4(u4* p) { 1698 intptr_t obj = nextPtr(); 1699 *p = (u4)(uintx(obj)); 1700 } 1701 1702 void do_tag(int tag) { 1703 int old_tag; 1704 old_tag = (int)(intptr_t)nextPtr(); 1705 // do_int(&old_tag); 1706 assert(tag == old_tag, "old tag doesn't match"); 1707 FileMapInfo::assert_mark(tag == old_tag); 1708 } 1709 1710 void do_region(u_char* start, size_t size) { 1711 assert((intptr_t)start % sizeof(intptr_t) == 0, "bad alignment"); 1712 assert(size % sizeof(intptr_t) == 0, "bad size"); 1713 do_tag((int)size); 1714 while (size > 0) { 1715 *(intptr_t*)start = nextPtr(); 1716 start += sizeof(intptr_t); 1717 size -= sizeof(intptr_t); 1718 } 1719 } 1720 1721 bool reading() const { return true; } 1722 }; 1723 1724 // Return true if given address is in the mapped shared space. 1725 bool MetaspaceShared::is_in_shared_space(const void* p) { 1726 return UseSharedSpaces && FileMapInfo::current_info()->is_in_shared_space(p); 1727 } 1728 1729 // Return true if given address is in the misc data region 1730 bool MetaspaceShared::is_in_shared_region(const void* p, int idx) { 1731 return UseSharedSpaces && FileMapInfo::current_info()->is_in_shared_region(p, idx); 1732 } 1733 1734 bool MetaspaceShared::is_in_trampoline_frame(address addr) { 1735 if (UseSharedSpaces && is_in_shared_region(addr, MetaspaceShared::mc)) { 1736 return true; 1737 } 1738 return false; 1739 } 1740 1741 void MetaspaceShared::print_shared_spaces() { 1742 if (UseSharedSpaces) { 1743 FileMapInfo::current_info()->print_shared_spaces(); 1744 } 1745 } 1746 1747 1748 // Map shared spaces at requested addresses and return if succeeded. 1749 bool MetaspaceShared::map_shared_spaces(FileMapInfo* mapinfo) { 1750 size_t image_alignment = mapinfo->alignment(); 1751 1752 #ifndef _WINDOWS 1753 // Map in the shared memory and then map the regions on top of it. 1754 // On Windows, don't map the memory here because it will cause the 1755 // mappings of the regions to fail. 1756 ReservedSpace shared_rs = mapinfo->reserve_shared_memory(); 1757 if (!shared_rs.is_reserved()) return false; 1758 #endif 1759 1760 assert(!DumpSharedSpaces, "Should not be called with DumpSharedSpaces"); 1761 1762 char* _ro_base = NULL; 1763 char* _rw_base = NULL; 1764 char* _mc_base = NULL; 1765 char* _md_base = NULL; 1766 char* _od_base = NULL; 1767 1768 // Map each shared region 1769 if ((_mc_base = mapinfo->map_region(mc)) != NULL && 1770 mapinfo->verify_region_checksum(mc) && 1771 (_rw_base = mapinfo->map_region(rw)) != NULL && 1772 mapinfo->verify_region_checksum(rw) && 1773 (_ro_base = mapinfo->map_region(ro)) != NULL && 1774 mapinfo->verify_region_checksum(ro) && 1775 (_md_base = mapinfo->map_region(md)) != NULL && 1776 mapinfo->verify_region_checksum(md) && 1777 (_od_base = mapinfo->map_region(od)) != NULL && 1778 mapinfo->verify_region_checksum(od) && 1779 (image_alignment == (size_t)os::vm_allocation_granularity()) && 1780 mapinfo->validate_classpath_entry_table()) { 1781 // Success (no need to do anything) 1782 return true; 1783 } else { 1784 // If there was a failure in mapping any of the spaces, unmap the ones 1785 // that succeeded 1786 if (_ro_base != NULL) mapinfo->unmap_region(ro); 1787 if (_rw_base != NULL) mapinfo->unmap_region(rw); 1788 if (_mc_base != NULL) mapinfo->unmap_region(mc); 1789 if (_md_base != NULL) mapinfo->unmap_region(md); 1790 if (_od_base != NULL) mapinfo->unmap_region(od); 1791 #ifndef _WINDOWS 1792 // Release the entire mapped region 1793 shared_rs.release(); 1794 #endif 1795 // If -Xshare:on is specified, print out the error message and exit VM, 1796 // otherwise, set UseSharedSpaces to false and continue. 1797 if (RequireSharedSpaces || PrintSharedArchiveAndExit) { 1798 vm_exit_during_initialization("Unable to use shared archive.", "Failed map_region for using -Xshare:on."); 1799 } else { 1800 FLAG_SET_DEFAULT(UseSharedSpaces, false); 1801 } 1802 return false; 1803 } 1804 } 1805 1806 // Read the miscellaneous data from the shared file, and 1807 // serialize it out to its various destinations. 1808 1809 void MetaspaceShared::initialize_shared_spaces() { 1810 FileMapInfo *mapinfo = FileMapInfo::current_info(); 1811 _cds_i2i_entry_code_buffers = mapinfo->cds_i2i_entry_code_buffers(); 1812 _cds_i2i_entry_code_buffers_size = mapinfo->cds_i2i_entry_code_buffers_size(); 1813 _core_spaces_size = mapinfo->core_spaces_size(); 1814 char* buffer = mapinfo->misc_data_patching_start(); 1815 clone_cpp_vtables((intptr_t*)buffer); 1816 1817 // The rest of the data is now stored in the RW region 1818 buffer = mapinfo->read_only_tables_start(); 1819 int sharedDictionaryLen = *(intptr_t*)buffer; 1820 buffer += sizeof(intptr_t); 1821 int number_of_entries = *(intptr_t*)buffer; 1822 buffer += sizeof(intptr_t); 1823 SystemDictionary::set_shared_dictionary((HashtableBucket<mtClass>*)buffer, 1824 sharedDictionaryLen, 1825 number_of_entries); 1826 buffer += sharedDictionaryLen; 1827 1828 // The following data are the linked list elements 1829 // (HashtableEntry objects) for the shared dictionary table. 1830 1831 int len = *(intptr_t*)buffer; // skip over shared dictionary entries 1832 buffer += sizeof(intptr_t); 1833 buffer += len; 1834 1835 // Verify various attributes of the archive, plus initialize the 1836 // shared string/symbol tables 1837 intptr_t* array = (intptr_t*)buffer; 1838 ReadClosure rc(&array); 1839 serialize(&rc); 1840 1841 // Initialize the run-time symbol table. 1842 SymbolTable::create_table(); 1843 1844 // Close the mapinfo file 1845 mapinfo->close(); 1846 1847 if (PrintSharedArchiveAndExit) { 1848 if (PrintSharedDictionary) { 1849 tty->print_cr("\nShared classes:\n"); 1850 SystemDictionary::print_shared(tty); 1851 } 1852 if (_archive_loading_failed) { 1853 tty->print_cr("archive is invalid"); 1854 vm_exit(1); 1855 } else { 1856 tty->print_cr("archive is valid"); 1857 vm_exit(0); 1858 } 1859 } 1860 } 1861 1862 // JVM/TI RedefineClasses() support: 1863 bool MetaspaceShared::remap_shared_readonly_as_readwrite() { 1864 assert(SafepointSynchronize::is_at_safepoint(), "must be at safepoint"); 1865 1866 if (UseSharedSpaces) { 1867 // remap the shared readonly space to shared readwrite, private 1868 FileMapInfo* mapinfo = FileMapInfo::current_info(); 1869 if (!mapinfo->remap_shared_readonly_as_readwrite()) { 1870 return false; 1871 } 1872 _remapped_readwrite = true; 1873 } 1874 return true; 1875 } 1876 1877 void MetaspaceShared::report_out_of_space(const char* name, size_t needed_bytes) { 1878 // This is highly unlikely to happen on 64-bits because we have reserved a 4GB space. 1879 // On 32-bit we reserve only 256MB so you could run out of space with 100,000 classes 1880 // or so. 1881 _mc_region.print_out_of_space_msg(name, needed_bytes); 1882 _rw_region.print_out_of_space_msg(name, needed_bytes); 1883 _ro_region.print_out_of_space_msg(name, needed_bytes); 1884 _md_region.print_out_of_space_msg(name, needed_bytes); 1885 _od_region.print_out_of_space_msg(name, needed_bytes); 1886 1887 vm_exit_during_initialization(err_msg("Unable to allocate from '%s' region", name), 1888 "Please reduce the number of shared classes."); 1889 }