1 /* 2 * Copyright (c) 2012, 2014, 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/dictionary.hpp" 27 #include "classfile/classLoaderExt.hpp" 28 #include "classfile/loaderConstraints.hpp" 29 #include "classfile/placeholders.hpp" 30 #include "classfile/sharedClassUtil.hpp" 31 #include "classfile/symbolTable.hpp" 32 #include "classfile/systemDictionary.hpp" 33 #include "code/codeCache.hpp" 34 #include "memory/filemap.hpp" 35 #include "memory/gcLocker.hpp" 36 #include "memory/metaspace.hpp" 37 #include "memory/metaspaceShared.hpp" 38 #include "oops/objArrayOop.hpp" 39 #include "oops/oop.inline.hpp" 40 #include "runtime/signature.hpp" 41 #include "runtime/vm_operations.hpp" 42 #include "runtime/vmThread.hpp" 43 #include "utilities/hashtable.hpp" 44 #include "utilities/hashtable.inline.hpp" 45 46 PRAGMA_FORMAT_MUTE_WARNINGS_FOR_GCC 47 48 int MetaspaceShared::_max_alignment = 0; 49 50 ReservedSpace* MetaspaceShared::_shared_rs = NULL; 51 52 bool MetaspaceShared::_link_classes_made_progress; 53 bool MetaspaceShared::_check_classes_made_progress; 54 bool MetaspaceShared::_has_error_classes; 55 bool MetaspaceShared::_archive_loading_failed = false; 56 // Read/write a data stream for restoring/preserving metadata pointers and 57 // miscellaneous data from/to the shared archive file. 58 59 void MetaspaceShared::serialize(SerializeClosure* soc) { 60 int tag = 0; 61 soc->do_tag(--tag); 62 63 // Verify the sizes of various metadata in the system. 64 soc->do_tag(sizeof(Method)); 65 soc->do_tag(sizeof(ConstMethod)); 66 soc->do_tag(arrayOopDesc::base_offset_in_bytes(T_BYTE)); 67 soc->do_tag(sizeof(ConstantPool)); 68 soc->do_tag(sizeof(ConstantPoolCache)); 69 soc->do_tag(objArrayOopDesc::base_offset_in_bytes()); 70 soc->do_tag(typeArrayOopDesc::base_offset_in_bytes(T_BYTE)); 71 soc->do_tag(sizeof(Symbol)); 72 73 // Dump/restore miscellaneous metadata. 74 Universe::serialize(soc, true); 75 soc->do_tag(--tag); 76 77 // Dump/restore references to commonly used names and signatures. 78 vmSymbols::serialize(soc); 79 soc->do_tag(--tag); 80 81 soc->do_tag(666); 82 } 83 84 85 // CDS code for dumping shared archive. 86 87 // Global object for holding classes that have been loaded. Since this 88 // is run at a safepoint just before exit, this is the entire set of classes. 89 static GrowableArray<Klass*>* _global_klass_objects; 90 static void collect_classes(Klass* k) { 91 _global_klass_objects->append_if_missing(k); 92 if (k->oop_is_instance()) { 93 // Add in the array classes too 94 InstanceKlass* ik = InstanceKlass::cast(k); 95 ik->array_klasses_do(collect_classes); 96 } 97 } 98 99 static void remove_unshareable_in_classes() { 100 for (int i = 0; i < _global_klass_objects->length(); i++) { 101 Klass* k = _global_klass_objects->at(i); 102 k->remove_unshareable_info(); 103 } 104 } 105 106 // Walk all methods in the class list and assign a fingerprint. 107 // so that this part of the ConstMethod* is read only. 108 static void calculate_fingerprints() { 109 for (int i = 0; i < _global_klass_objects->length(); i++) { 110 Klass* k = _global_klass_objects->at(i); 111 if (k->oop_is_instance()) { 112 InstanceKlass* ik = InstanceKlass::cast(k); 113 for (int i = 0; i < ik->methods()->length(); i++) { 114 Method* m = ik->methods()->at(i); 115 Fingerprinter fp(m); 116 // The side effect of this call sets method's fingerprint field. 117 fp.fingerprint(); 118 } 119 } 120 } 121 } 122 123 // Patch C++ vtable pointer in metadata. 124 125 // Klass and other metadata objects contain references to c++ vtables in the 126 // JVM library. 127 // Fix them to point to our constructed vtables. However, don't iterate 128 // across the space while doing this, as that causes the vtables to be 129 // patched, undoing our useful work. Instead, iterate to make a list, 130 // then use the list to do the fixing. 131 // 132 // Our constructed vtables: 133 // Dump time: 134 // 1. init_self_patching_vtbl_list: table of pointers to current virtual method addrs 135 // 2. generate_vtable_methods: create jump table, appended to above vtbl_list 136 // 3. patch_klass_vtables: for Klass list, patch the vtable entry in klass and 137 // associated metadata to point to jump table rather than to current vtbl 138 // Table layout: NOTE FIXED SIZE 139 // 1. vtbl pointers 140 // 2. #Klass X #virtual methods per Klass 141 // 1 entry for each, in the order: 142 // Klass1:method1 entry, Klass1:method2 entry, ... Klass1:method<num_virtuals> entry 143 // Klass2:method1 entry, Klass2:method2 entry, ... Klass2:method<num_virtuals> entry 144 // ... 145 // Klass<vtbl_list_size>:method1 entry, Klass<vtbl_list_size>:method2 entry, 146 // ... Klass<vtbl_list_size>:method<num_virtuals> entry 147 // Sample entry: (Sparc): 148 // save(sp, -256, sp) 149 // ba,pt common_code 150 // mov XXX, %L0 %L0 gets: Klass index <<8 + method index (note: max method index 255) 151 // 152 // Restore time: 153 // 1. initialize_shared_space: reserve space for table 154 // 2. init_self_patching_vtbl_list: update pointers to NEW virtual method addrs in text 155 // 156 // Execution time: 157 // First virtual method call for any object of these metadata types: 158 // 1. object->klass 159 // 2. vtable entry for that klass points to the jump table entries 160 // 3. branches to common_code with %O0/klass, %L0: Klass index <<8 + method index 161 // 4. common_code: 162 // Get address of new vtbl pointer for this Klass from updated table 163 // Update new vtbl pointer in the Klass: future virtual calls go direct 164 // Jump to method, using new vtbl pointer and method index 165 166 167 static void* find_matching_vtbl_ptr(void** vtbl_list, void* new_vtable_start, void* obj) { 168 void* old_vtbl_ptr = *(void**)obj; 169 for (int i = 0; i < MetaspaceShared::vtbl_list_size; i++) { 170 if (vtbl_list[i] == old_vtbl_ptr) { 171 return (void**)new_vtable_start + i * MetaspaceShared::num_virtuals; 172 } 173 } 174 ShouldNotReachHere(); 175 return NULL; 176 } 177 178 // Assumes the vtable is in first slot in object. 179 static void patch_klass_vtables(void** vtbl_list, void* new_vtable_start) { 180 int n = _global_klass_objects->length(); 181 for (int i = 0; i < n; i++) { 182 Klass* obj = _global_klass_objects->at(i); 183 // Note oop_is_instance() is a virtual call. After patching vtables 184 // all virtual calls on the dummy vtables will restore the original! 185 if (obj->oop_is_instance()) { 186 InstanceKlass* ik = InstanceKlass::cast(obj); 187 *(void**)ik = find_matching_vtbl_ptr(vtbl_list, new_vtable_start, ik); 188 ConstantPool* cp = ik->constants(); 189 *(void**)cp = find_matching_vtbl_ptr(vtbl_list, new_vtable_start, cp); 190 for (int j = 0; j < ik->methods()->length(); j++) { 191 Method* m = ik->methods()->at(j); 192 *(void**)m = find_matching_vtbl_ptr(vtbl_list, new_vtable_start, m); 193 } 194 } else { 195 // Array klasses 196 Klass* k = obj; 197 *(void**)k = find_matching_vtbl_ptr(vtbl_list, new_vtable_start, k); 198 } 199 } 200 } 201 202 // Closure for serializing initialization data out to a data area to be 203 // written to the shared file. 204 205 class WriteClosure : public SerializeClosure { 206 private: 207 intptr_t* top; 208 char* end; 209 210 inline void check_space() { 211 if ((char*)top + sizeof(intptr_t) > end) { 212 report_out_of_shared_space(SharedMiscData); 213 } 214 } 215 216 public: 217 WriteClosure(char* md_top, char* md_end) { 218 top = (intptr_t*)md_top; 219 end = md_end; 220 } 221 222 char* get_top() { return (char*)top; } 223 224 void do_ptr(void** p) { 225 check_space(); 226 *top = (intptr_t)*p; 227 ++top; 228 } 229 230 void do_tag(int tag) { 231 check_space(); 232 *top = (intptr_t)tag; 233 ++top; 234 } 235 236 void do_region(u_char* start, size_t size) { 237 if ((char*)top + size > end) { 238 report_out_of_shared_space(SharedMiscData); 239 } 240 assert((intptr_t)start % sizeof(intptr_t) == 0, "bad alignment"); 241 assert(size % sizeof(intptr_t) == 0, "bad size"); 242 do_tag((int)size); 243 while (size > 0) { 244 *top = *(intptr_t*)start; 245 ++top; 246 start += sizeof(intptr_t); 247 size -= sizeof(intptr_t); 248 } 249 } 250 251 bool reading() const { return false; } 252 }; 253 254 // This is for dumping detailed statistics for the allocations 255 // in the shared spaces. 256 class DumpAllocClosure : public Metaspace::AllocRecordClosure { 257 public: 258 259 // Here's poor man's enum inheritance 260 #define SHAREDSPACE_OBJ_TYPES_DO(f) \ 261 METASPACE_OBJ_TYPES_DO(f) \ 262 f(SymbolHashentry) \ 263 f(SymbolBuckets) \ 264 f(Other) 265 266 #define SHAREDSPACE_OBJ_TYPE_DECLARE(name) name ## Type, 267 #define SHAREDSPACE_OBJ_TYPE_NAME_CASE(name) case name ## Type: return #name; 268 269 enum Type { 270 // Types are MetaspaceObj::ClassType, MetaspaceObj::SymbolType, etc 271 SHAREDSPACE_OBJ_TYPES_DO(SHAREDSPACE_OBJ_TYPE_DECLARE) 272 _number_of_types 273 }; 274 275 static const char * type_name(Type type) { 276 switch(type) { 277 SHAREDSPACE_OBJ_TYPES_DO(SHAREDSPACE_OBJ_TYPE_NAME_CASE) 278 default: 279 ShouldNotReachHere(); 280 return NULL; 281 } 282 } 283 284 public: 285 enum { 286 RO = 0, 287 RW = 1 288 }; 289 290 int _counts[2][_number_of_types]; 291 int _bytes [2][_number_of_types]; 292 int _which; 293 294 DumpAllocClosure() { 295 memset(_counts, 0, sizeof(_counts)); 296 memset(_bytes, 0, sizeof(_bytes)); 297 }; 298 299 void iterate_metaspace(Metaspace* space, int which) { 300 assert(which == RO || which == RW, "sanity"); 301 _which = which; 302 space->iterate(this); 303 } 304 305 virtual void doit(address ptr, MetaspaceObj::Type type, int byte_size) { 306 assert(int(type) >= 0 && type < MetaspaceObj::_number_of_types, "sanity"); 307 _counts[_which][type] ++; 308 _bytes [_which][type] += byte_size; 309 } 310 311 void dump_stats(int ro_all, int rw_all, int md_all, int mc_all); 312 }; 313 314 void DumpAllocClosure::dump_stats(int ro_all, int rw_all, int md_all, int mc_all) { 315 rw_all += (md_all + mc_all); // md and mc are all mapped Read/Write 316 int other_bytes = md_all + mc_all; 317 318 // Calculate size of data that was not allocated by Metaspace::allocate() 319 int symbol_count = _counts[RO][MetaspaceObj::SymbolType]; 320 int symhash_bytes = symbol_count * sizeof (HashtableEntry<Symbol*, mtSymbol>); 321 int symbuck_count = SymbolTable::the_table()->table_size(); 322 int symbuck_bytes = symbuck_count * sizeof(HashtableBucket<mtSymbol>); 323 324 _counts[RW][SymbolHashentryType] = symbol_count; 325 _bytes [RW][SymbolHashentryType] = symhash_bytes; 326 other_bytes -= symhash_bytes; 327 328 _counts[RW][SymbolBucketsType] = symbuck_count; 329 _bytes [RW][SymbolBucketsType] = symbuck_bytes; 330 other_bytes -= symbuck_bytes; 331 332 // TODO: count things like dictionary, vtable, etc 333 _bytes[RW][OtherType] = other_bytes; 334 335 // prevent divide-by-zero 336 if (ro_all < 1) { 337 ro_all = 1; 338 } 339 if (rw_all < 1) { 340 rw_all = 1; 341 } 342 343 int all_ro_count = 0; 344 int all_ro_bytes = 0; 345 int all_rw_count = 0; 346 int all_rw_bytes = 0; 347 348 // To make fmt_stats be a syntactic constant (for format warnings), use #define. 349 #define fmt_stats "%-20s: %8d %10d %5.1f | %8d %10d %5.1f | %8d %10d %5.1f" 350 const char *sep = "--------------------+---------------------------+---------------------------+--------------------------"; 351 const char *hdr = " ro_cnt ro_bytes % | rw_cnt rw_bytes % | all_cnt all_bytes %"; 352 353 tty->print_cr("Detailed metadata info (rw includes md and mc):"); 354 tty->print_cr("%s", hdr); 355 tty->print_cr("%s", sep); 356 for (int type = 0; type < int(_number_of_types); type ++) { 357 const char *name = type_name((Type)type); 358 int ro_count = _counts[RO][type]; 359 int ro_bytes = _bytes [RO][type]; 360 int rw_count = _counts[RW][type]; 361 int rw_bytes = _bytes [RW][type]; 362 int count = ro_count + rw_count; 363 int bytes = ro_bytes + rw_bytes; 364 365 double ro_perc = 100.0 * double(ro_bytes) / double(ro_all); 366 double rw_perc = 100.0 * double(rw_bytes) / double(rw_all); 367 double perc = 100.0 * double(bytes) / double(ro_all + rw_all); 368 369 tty->print_cr(fmt_stats, name, 370 ro_count, ro_bytes, ro_perc, 371 rw_count, rw_bytes, rw_perc, 372 count, bytes, perc); 373 374 all_ro_count += ro_count; 375 all_ro_bytes += ro_bytes; 376 all_rw_count += rw_count; 377 all_rw_bytes += rw_bytes; 378 } 379 380 int all_count = all_ro_count + all_rw_count; 381 int all_bytes = all_ro_bytes + all_rw_bytes; 382 383 double all_ro_perc = 100.0 * double(all_ro_bytes) / double(ro_all); 384 double all_rw_perc = 100.0 * double(all_rw_bytes) / double(rw_all); 385 double all_perc = 100.0 * double(all_bytes) / double(ro_all + rw_all); 386 387 tty->print_cr("%s", sep); 388 tty->print_cr(fmt_stats, "Total", 389 all_ro_count, all_ro_bytes, all_ro_perc, 390 all_rw_count, all_rw_bytes, all_rw_perc, 391 all_count, all_bytes, all_perc); 392 393 assert(all_ro_bytes == ro_all, "everything should have been counted"); 394 assert(all_rw_bytes == rw_all, "everything should have been counted"); 395 #undef fmt_stats 396 } 397 398 // Populate the shared space. 399 400 class VM_PopulateDumpSharedSpace: public VM_Operation { 401 private: 402 ClassLoaderData* _loader_data; 403 GrowableArray<Klass*> *_class_promote_order; 404 VirtualSpace _md_vs; 405 VirtualSpace _mc_vs; 406 407 public: 408 VM_PopulateDumpSharedSpace(ClassLoaderData* loader_data, 409 GrowableArray<Klass*> *class_promote_order) : 410 _loader_data(loader_data) { 411 412 // Split up and initialize the misc code and data spaces 413 ReservedSpace* shared_rs = MetaspaceShared::shared_rs(); 414 int metadata_size = SharedReadOnlySize+SharedReadWriteSize; 415 ReservedSpace shared_ro_rw = shared_rs->first_part(metadata_size); 416 ReservedSpace misc_section = shared_rs->last_part(metadata_size); 417 418 // Now split into misc sections. 419 ReservedSpace md_rs = misc_section.first_part(SharedMiscDataSize); 420 ReservedSpace mc_rs = misc_section.last_part(SharedMiscDataSize); 421 _md_vs.initialize(md_rs, SharedMiscDataSize); 422 _mc_vs.initialize(mc_rs, SharedMiscCodeSize); 423 _class_promote_order = class_promote_order; 424 } 425 426 VMOp_Type type() const { return VMOp_PopulateDumpSharedSpace; } 427 void doit(); // outline because gdb sucks 428 }; // class VM_PopulateDumpSharedSpace 429 430 431 void VM_PopulateDumpSharedSpace::doit() { 432 Thread* THREAD = VMThread::vm_thread(); 433 NOT_PRODUCT(SystemDictionary::verify();) 434 // The following guarantee is meant to ensure that no loader constraints 435 // exist yet, since the constraints table is not shared. This becomes 436 // more important now that we don't re-initialize vtables/itables for 437 // shared classes at runtime, where constraints were previously created. 438 guarantee(SystemDictionary::constraints()->number_of_entries() == 0, 439 "loader constraints are not saved"); 440 guarantee(SystemDictionary::placeholders()->number_of_entries() == 0, 441 "placeholders are not saved"); 442 // Revisit and implement this if we prelink method handle call sites: 443 guarantee(SystemDictionary::invoke_method_table() == NULL || 444 SystemDictionary::invoke_method_table()->number_of_entries() == 0, 445 "invoke method table is not saved"); 446 447 // At this point, many classes have been loaded. 448 // Gather systemDictionary classes in a global array and do everything to 449 // that so we don't have to walk the SystemDictionary again. 450 _global_klass_objects = new GrowableArray<Klass*>(1000); 451 Universe::basic_type_classes_do(collect_classes); 452 SystemDictionary::classes_do(collect_classes); 453 454 tty->print_cr("Number of classes %d", _global_klass_objects->length()); 455 { 456 int num_type_array = 0, num_obj_array = 0, num_inst = 0; 457 for (int i = 0; i < _global_klass_objects->length(); i++) { 458 Klass* k = _global_klass_objects->at(i); 459 if (k->oop_is_instance()) { 460 num_inst ++; 461 } else if (k->oop_is_objArray()) { 462 num_obj_array ++; 463 } else { 464 assert(k->oop_is_typeArray(), "sanity"); 465 num_type_array ++; 466 } 467 } 468 tty->print_cr(" instance classes = %5d", num_inst); 469 tty->print_cr(" obj array classes = %5d", num_obj_array); 470 tty->print_cr(" type array classes = %5d", num_type_array); 471 } 472 473 // Update all the fingerprints in the shared methods. 474 tty->print("Calculating fingerprints ... "); 475 calculate_fingerprints(); 476 tty->print_cr("done. "); 477 478 // Remove all references outside the metadata 479 tty->print("Removing unshareable information ... "); 480 remove_unshareable_in_classes(); 481 tty->print_cr("done. "); 482 483 // Set up the share data and shared code segments. 484 char* md_low = _md_vs.low(); 485 char* md_top = md_low; 486 char* md_end = _md_vs.high(); 487 char* mc_low = _mc_vs.low(); 488 char* mc_top = mc_low; 489 char* mc_end = _mc_vs.high(); 490 491 // Reserve space for the list of Klass*s whose vtables are used 492 // for patching others as needed. 493 494 void** vtbl_list = (void**)md_top; 495 int vtbl_list_size = MetaspaceShared::vtbl_list_size; 496 Universe::init_self_patching_vtbl_list(vtbl_list, vtbl_list_size); 497 498 md_top += vtbl_list_size * sizeof(void*); 499 void* vtable = md_top; 500 501 // Reserve space for a new dummy vtable for klass objects in the 502 // heap. Generate self-patching vtable entries. 503 504 MetaspaceShared::generate_vtable_methods(vtbl_list, &vtable, 505 &md_top, md_end, 506 &mc_top, mc_end); 507 508 // Reorder the system dictionary. (Moving the symbols affects 509 // how the hash table indices are calculated.) 510 // Not doing this either. 511 512 SystemDictionary::reorder_dictionary(); 513 514 NOT_PRODUCT(SystemDictionary::verify();) 515 516 // Copy the the symbol table, and the system dictionary to the shared 517 // space in usable form. Copy the hastable 518 // buckets first [read-write], then copy the linked lists of entries 519 // [read-only]. 520 521 SymbolTable::reverse(md_top); 522 NOT_PRODUCT(SymbolTable::verify()); 523 SymbolTable::copy_buckets(&md_top, md_end); 524 525 SystemDictionary::reverse(); 526 SystemDictionary::copy_buckets(&md_top, md_end); 527 528 ClassLoader::verify(); 529 ClassLoader::copy_package_info_buckets(&md_top, md_end); 530 ClassLoader::verify(); 531 532 SymbolTable::copy_table(&md_top, md_end); 533 SystemDictionary::copy_table(&md_top, md_end); 534 ClassLoader::verify(); 535 ClassLoader::copy_package_info_table(&md_top, md_end); 536 ClassLoader::verify(); 537 538 ClassLoaderExt::copy_lookup_cache_to_archive(&md_top, md_end); 539 540 // Write the other data to the output array. 541 WriteClosure wc(md_top, md_end); 542 MetaspaceShared::serialize(&wc); 543 md_top = wc.get_top(); 544 545 // Print shared spaces all the time 546 // To make fmt_space be a syntactic constant (for format warnings), use #define. 547 #define fmt_space "%s space: %9d [ %4.1f%% of total] out of %9d bytes [%4.1f%% used] at " PTR_FORMAT 548 Metaspace* ro_space = _loader_data->ro_metaspace(); 549 Metaspace* rw_space = _loader_data->rw_metaspace(); 550 551 // Allocated size of each space (may not be all occupied) 552 const size_t ro_alloced = ro_space->capacity_bytes_slow(Metaspace::NonClassType); 553 const size_t rw_alloced = rw_space->capacity_bytes_slow(Metaspace::NonClassType); 554 const size_t md_alloced = md_end-md_low; 555 const size_t mc_alloced = mc_end-mc_low; 556 const size_t total_alloced = ro_alloced + rw_alloced + md_alloced + mc_alloced; 557 558 // Occupied size of each space. 559 const size_t ro_bytes = ro_space->used_bytes_slow(Metaspace::NonClassType); 560 const size_t rw_bytes = rw_space->used_bytes_slow(Metaspace::NonClassType); 561 const size_t md_bytes = size_t(md_top - md_low); 562 const size_t mc_bytes = size_t(mc_top - mc_low); 563 564 // Percent of total size 565 const size_t total_bytes = ro_bytes + rw_bytes + md_bytes + mc_bytes; 566 const double ro_t_perc = ro_bytes / double(total_bytes) * 100.0; 567 const double rw_t_perc = rw_bytes / double(total_bytes) * 100.0; 568 const double md_t_perc = md_bytes / double(total_bytes) * 100.0; 569 const double mc_t_perc = mc_bytes / double(total_bytes) * 100.0; 570 571 // Percent of fullness of each space 572 const double ro_u_perc = ro_bytes / double(ro_alloced) * 100.0; 573 const double rw_u_perc = rw_bytes / double(rw_alloced) * 100.0; 574 const double md_u_perc = md_bytes / double(md_alloced) * 100.0; 575 const double mc_u_perc = mc_bytes / double(mc_alloced) * 100.0; 576 const double total_u_perc = total_bytes / double(total_alloced) * 100.0; 577 578 tty->print_cr(fmt_space, "ro", ro_bytes, ro_t_perc, ro_alloced, ro_u_perc, ro_space->bottom()); 579 tty->print_cr(fmt_space, "rw", rw_bytes, rw_t_perc, rw_alloced, rw_u_perc, rw_space->bottom()); 580 tty->print_cr(fmt_space, "md", md_bytes, md_t_perc, md_alloced, md_u_perc, md_low); 581 tty->print_cr(fmt_space, "mc", mc_bytes, mc_t_perc, mc_alloced, mc_u_perc, mc_low); 582 tty->print_cr("total : %9d [100.0%% of total] out of %9d bytes [%4.1f%% used]", 583 total_bytes, total_alloced, total_u_perc); 584 585 // Update the vtable pointers in all of the Klass objects in the 586 // heap. They should point to newly generated vtable. 587 patch_klass_vtables(vtbl_list, vtable); 588 589 // dunno what this is for. 590 char* saved_vtbl = (char*)os::malloc(vtbl_list_size * sizeof(void*), mtClass); 591 memmove(saved_vtbl, vtbl_list, vtbl_list_size * sizeof(void*)); 592 memset(vtbl_list, 0, vtbl_list_size * sizeof(void*)); 593 594 // Create and write the archive file that maps the shared spaces. 595 596 FileMapInfo* mapinfo = new FileMapInfo(); 597 mapinfo->populate_header(MetaspaceShared::max_alignment()); 598 599 // Pass 1 - update file offsets in header. 600 mapinfo->write_header(); 601 mapinfo->write_space(MetaspaceShared::ro, _loader_data->ro_metaspace(), true); 602 mapinfo->write_space(MetaspaceShared::rw, _loader_data->rw_metaspace(), false); 603 mapinfo->write_region(MetaspaceShared::md, _md_vs.low(), 604 pointer_delta(md_top, _md_vs.low(), sizeof(char)), 605 SharedMiscDataSize, 606 false, false); 607 mapinfo->write_region(MetaspaceShared::mc, _mc_vs.low(), 608 pointer_delta(mc_top, _mc_vs.low(), sizeof(char)), 609 SharedMiscCodeSize, 610 true, true); 611 612 // Pass 2 - write data. 613 mapinfo->open_for_write(); 614 mapinfo->set_header_crc(mapinfo->compute_header_crc()); 615 mapinfo->write_header(); 616 mapinfo->write_space(MetaspaceShared::ro, _loader_data->ro_metaspace(), true); 617 mapinfo->write_space(MetaspaceShared::rw, _loader_data->rw_metaspace(), false); 618 mapinfo->write_region(MetaspaceShared::md, _md_vs.low(), 619 pointer_delta(md_top, _md_vs.low(), sizeof(char)), 620 SharedMiscDataSize, 621 false, false); 622 mapinfo->write_region(MetaspaceShared::mc, _mc_vs.low(), 623 pointer_delta(mc_top, _mc_vs.low(), sizeof(char)), 624 SharedMiscCodeSize, 625 true, true); 626 mapinfo->close(); 627 628 memmove(vtbl_list, saved_vtbl, vtbl_list_size * sizeof(void*)); 629 630 if (PrintSharedSpaces) { 631 DumpAllocClosure dac; 632 dac.iterate_metaspace(_loader_data->ro_metaspace(), DumpAllocClosure::RO); 633 dac.iterate_metaspace(_loader_data->rw_metaspace(), DumpAllocClosure::RW); 634 635 dac.dump_stats(int(ro_bytes), int(rw_bytes), int(md_bytes), int(mc_bytes)); 636 } 637 #undef fmt_space 638 } 639 640 641 void MetaspaceShared::link_one_shared_class(Klass* obj, TRAPS) { 642 Klass* k = obj; 643 if (k->oop_is_instance()) { 644 InstanceKlass* ik = (InstanceKlass*) k; 645 // Link the class to cause the bytecodes to be rewritten and the 646 // cpcache to be created. Class verification is done according 647 // to -Xverify setting. 648 _link_classes_made_progress |= try_link_class(ik, THREAD); 649 guarantee(!HAS_PENDING_EXCEPTION, "exception in link_class"); 650 } 651 } 652 653 void MetaspaceShared::check_one_shared_class(Klass* k) { 654 if (k->oop_is_instance() && InstanceKlass::cast(k)->check_sharing_error_state()) { 655 _check_classes_made_progress = true; 656 } 657 } 658 659 void MetaspaceShared::link_and_cleanup_shared_classes(TRAPS) { 660 // We need to iterate because verification may cause additional classes 661 // to be loaded. 662 do { 663 _link_classes_made_progress = false; 664 SystemDictionary::classes_do(link_one_shared_class, THREAD); 665 guarantee(!HAS_PENDING_EXCEPTION, "exception in link_class"); 666 } while (_link_classes_made_progress); 667 668 if (_has_error_classes) { 669 // Mark all classes whose super class or interfaces failed verification. 670 do { 671 // Not completely sure if we need to do this iteratively. Anyway, 672 // we should come here only if there are unverifiable classes, which 673 // shouldn't happen in normal cases. So better safe than sorry. 674 _check_classes_made_progress = false; 675 SystemDictionary::classes_do(check_one_shared_class); 676 } while (_check_classes_made_progress); 677 678 if (IgnoreUnverifiableClassesDuringDump) { 679 // This is useful when running JCK or SQE tests. You should not 680 // enable this when running real apps. 681 SystemDictionary::remove_classes_in_error_state(); 682 } else { 683 tty->print_cr("Please remove the unverifiable classes from your class list and try again"); 684 exit(1); 685 } 686 } 687 } 688 689 void MetaspaceShared::prepare_for_dumping() { 690 ClassLoader::initialize_shared_path(); 691 FileMapInfo::allocate_classpath_entry_table(); 692 } 693 694 // Preload classes from a list, populate the shared spaces and dump to a 695 // file. 696 void MetaspaceShared::preload_and_dump(TRAPS) { 697 TraceTime timer("Dump Shared Spaces", TraceStartupTime); 698 ResourceMark rm; 699 700 tty->print_cr("Allocated shared space: %d bytes at " PTR_FORMAT, 701 MetaspaceShared::shared_rs()->size(), 702 MetaspaceShared::shared_rs()->base()); 703 704 // Preload classes to be shared. 705 // Should use some os:: method rather than fopen() here. aB. 706 const char* class_list_path; 707 if (SharedClassListFile == NULL) { 708 // Construct the path to the class list (in jre/lib) 709 // Walk up two directories from the location of the VM and 710 // optionally tack on "lib" (depending on platform) 711 char class_list_path_str[JVM_MAXPATHLEN]; 712 os::jvm_path(class_list_path_str, sizeof(class_list_path_str)); 713 for (int i = 0; i < 3; i++) { 714 char *end = strrchr(class_list_path_str, *os::file_separator()); 715 if (end != NULL) *end = '\0'; 716 } 717 int class_list_path_len = (int)strlen(class_list_path_str); 718 if (class_list_path_len >= 3) { 719 if (strcmp(class_list_path_str + class_list_path_len - 3, "lib") != 0) { 720 strcat(class_list_path_str, os::file_separator()); 721 strcat(class_list_path_str, "lib"); 722 } 723 } 724 strcat(class_list_path_str, os::file_separator()); 725 strcat(class_list_path_str, "classlist"); 726 class_list_path = class_list_path_str; 727 } else { 728 class_list_path = SharedClassListFile; 729 } 730 731 int class_count = 0; 732 GrowableArray<Klass*>* class_promote_order = new GrowableArray<Klass*>(); 733 734 // sun.io.Converters 735 static const char obj_array_sig[] = "[[Ljava/lang/Object;"; 736 SymbolTable::new_permanent_symbol(obj_array_sig, THREAD); 737 738 // java.util.HashMap 739 static const char map_entry_array_sig[] = "[Ljava/util/Map$Entry;"; 740 SymbolTable::new_permanent_symbol(map_entry_array_sig, THREAD); 741 742 tty->print_cr("Loading classes to share ..."); 743 _has_error_classes = false; 744 class_count += preload_and_dump(class_list_path, class_promote_order, 745 THREAD); 746 if (ExtraSharedClassListFile) { 747 class_count += preload_and_dump(ExtraSharedClassListFile, class_promote_order, 748 THREAD); 749 } 750 tty->print_cr("Loading classes to share: done."); 751 752 ClassLoaderExt::init_lookup_cache(THREAD); 753 754 if (PrintSharedSpaces) { 755 tty->print_cr("Shared spaces: preloaded %d classes", class_count); 756 } 757 758 // Rewrite and link classes 759 tty->print_cr("Rewriting and linking classes ..."); 760 761 // Link any classes which got missed. This would happen if we have loaded classes that 762 // were not explicitly specified in the classlist. E.g., if an interface implemented by class K 763 // fails verification, all other interfaces that were not specified in the classlist but 764 // are implemented by K are not verified. 765 link_and_cleanup_shared_classes(CATCH); 766 tty->print_cr("Rewriting and linking classes: done"); 767 768 // Create and dump the shared spaces. Everything so far is loaded 769 // with the null class loader. 770 ClassLoaderData* loader_data = ClassLoaderData::the_null_class_loader_data(); 771 VM_PopulateDumpSharedSpace op(loader_data, class_promote_order); 772 VMThread::execute(&op); 773 774 // Since various initialization steps have been undone by this process, 775 // it is not reasonable to continue running a java process. 776 exit(0); 777 } 778 779 int MetaspaceShared::preload_and_dump(const char * class_list_path, 780 GrowableArray<Klass*>* class_promote_order, 781 TRAPS) { 782 FILE* file = fopen(class_list_path, "r"); 783 char class_name[256]; 784 int class_count = 0; 785 786 if (file != NULL) { 787 while ((fgets(class_name, sizeof class_name, file)) != NULL) { 788 if (*class_name == '#') { // comment 789 continue; 790 } 791 // Remove trailing newline 792 size_t name_len = strlen(class_name); 793 if (class_name[name_len-1] == '\n') { 794 class_name[name_len-1] = '\0'; 795 } 796 797 // Got a class name - load it. 798 TempNewSymbol class_name_symbol = SymbolTable::new_permanent_symbol(class_name, THREAD); 799 guarantee(!HAS_PENDING_EXCEPTION, "Exception creating a symbol."); 800 Klass* klass = SystemDictionary::resolve_or_null(class_name_symbol, 801 THREAD); 802 CLEAR_PENDING_EXCEPTION; 803 if (klass != NULL) { 804 if (PrintSharedSpaces && Verbose && WizardMode) { 805 tty->print_cr("Shared spaces preloaded: %s", class_name); 806 } 807 808 InstanceKlass* ik = InstanceKlass::cast(klass); 809 810 // Should be class load order as per -XX:+TraceClassLoadingPreorder 811 class_promote_order->append(ik); 812 813 // Link the class to cause the bytecodes to be rewritten and the 814 // cpcache to be created. The linking is done as soon as classes 815 // are loaded in order that the related data structures (klass and 816 // cpCache) are located together. 817 try_link_class(ik, THREAD); 818 guarantee(!HAS_PENDING_EXCEPTION, "exception in link_class"); 819 820 class_count++; 821 } else { 822 //tty->print_cr("Preload failed: %s", class_name); 823 } 824 } 825 fclose(file); 826 } else { 827 char errmsg[JVM_MAXPATHLEN]; 828 os::lasterror(errmsg, JVM_MAXPATHLEN); 829 tty->print_cr("Loading classlist failed: %s", errmsg); 830 exit(1); 831 } 832 833 return class_count; 834 } 835 836 // Returns true if the class's status has changed 837 bool MetaspaceShared::try_link_class(InstanceKlass* ik, TRAPS) { 838 assert(DumpSharedSpaces, "should only be called during dumping"); 839 if (ik->init_state() < InstanceKlass::linked) { 840 bool saved = BytecodeVerificationLocal; 841 if (!SharedClassUtil::is_shared_boot_class(ik)) { 842 // The verification decision is based on BytecodeVerificationRemote 843 // for non-system classes. Since we are using the NULL classloader 844 // to load non-system classes during dumping, we need to temporarily 845 // change BytecodeVerificationLocal to be the same as 846 // BytecodeVerificationRemote. Note this can cause the parent system 847 // classes also being verified. The extra overhead is acceptable during 848 // dumping. 849 BytecodeVerificationLocal = BytecodeVerificationRemote; 850 } 851 ik->link_class(THREAD); 852 if (HAS_PENDING_EXCEPTION) { 853 ResourceMark rm; 854 tty->print_cr("Preload Error: Verification failed for %s", 855 ik->external_name()); 856 CLEAR_PENDING_EXCEPTION; 857 ik->set_in_error_state(); 858 _has_error_classes = true; 859 } 860 BytecodeVerificationLocal = saved; 861 return true; 862 } else { 863 return false; 864 } 865 } 866 867 // Closure for serializing initialization data in from a data area 868 // (ptr_array) read from the shared file. 869 870 class ReadClosure : public SerializeClosure { 871 private: 872 intptr_t** _ptr_array; 873 874 inline intptr_t nextPtr() { 875 return *(*_ptr_array)++; 876 } 877 878 public: 879 ReadClosure(intptr_t** ptr_array) { _ptr_array = ptr_array; } 880 881 void do_ptr(void** p) { 882 assert(*p == NULL, "initializing previous initialized pointer."); 883 intptr_t obj = nextPtr(); 884 assert((intptr_t)obj >= 0 || (intptr_t)obj < -100, 885 "hit tag while initializing ptrs."); 886 *p = (void*)obj; 887 } 888 889 void do_tag(int tag) { 890 int old_tag; 891 old_tag = (int)(intptr_t)nextPtr(); 892 // do_int(&old_tag); 893 assert(tag == old_tag, "old tag doesn't match"); 894 FileMapInfo::assert_mark(tag == old_tag); 895 } 896 897 void do_region(u_char* start, size_t size) { 898 assert((intptr_t)start % sizeof(intptr_t) == 0, "bad alignment"); 899 assert(size % sizeof(intptr_t) == 0, "bad size"); 900 do_tag((int)size); 901 while (size > 0) { 902 *(intptr_t*)start = nextPtr(); 903 start += sizeof(intptr_t); 904 size -= sizeof(intptr_t); 905 } 906 } 907 908 bool reading() const { return true; } 909 }; 910 911 // Return true if given address is in the mapped shared space. 912 bool MetaspaceShared::is_in_shared_space(const void* p) { 913 return UseSharedSpaces && FileMapInfo::current_info()->is_in_shared_space(p); 914 } 915 916 void MetaspaceShared::print_shared_spaces() { 917 if (UseSharedSpaces) { 918 FileMapInfo::current_info()->print_shared_spaces(); 919 } 920 } 921 922 923 // Map shared spaces at requested addresses and return if succeeded. 924 // Need to keep the bounds of the ro and rw space for the Metaspace::contains 925 // call, or is_in_shared_space. 926 bool MetaspaceShared::map_shared_spaces(FileMapInfo* mapinfo) { 927 size_t image_alignment = mapinfo->alignment(); 928 929 #ifndef _WINDOWS 930 // Map in the shared memory and then map the regions on top of it. 931 // On Windows, don't map the memory here because it will cause the 932 // mappings of the regions to fail. 933 ReservedSpace shared_rs = mapinfo->reserve_shared_memory(); 934 if (!shared_rs.is_reserved()) return false; 935 #endif 936 937 assert(!DumpSharedSpaces, "Should not be called with DumpSharedSpaces"); 938 939 char* _ro_base = NULL; 940 char* _rw_base = NULL; 941 char* _md_base = NULL; 942 char* _mc_base = NULL; 943 944 // Map each shared region 945 if ((_ro_base = mapinfo->map_region(ro)) != NULL && 946 mapinfo->verify_region_checksum(ro) && 947 (_rw_base = mapinfo->map_region(rw)) != NULL && 948 mapinfo->verify_region_checksum(rw) && 949 (_md_base = mapinfo->map_region(md)) != NULL && 950 mapinfo->verify_region_checksum(md) && 951 (_mc_base = mapinfo->map_region(mc)) != NULL && 952 mapinfo->verify_region_checksum(mc) && 953 (image_alignment == (size_t)max_alignment()) && 954 mapinfo->validate_classpath_entry_table()) { 955 // Success (no need to do anything) 956 return true; 957 } else { 958 // If there was a failure in mapping any of the spaces, unmap the ones 959 // that succeeded 960 if (_ro_base != NULL) mapinfo->unmap_region(ro); 961 if (_rw_base != NULL) mapinfo->unmap_region(rw); 962 if (_md_base != NULL) mapinfo->unmap_region(md); 963 if (_mc_base != NULL) mapinfo->unmap_region(mc); 964 #ifndef _WINDOWS 965 // Release the entire mapped region 966 shared_rs.release(); 967 #endif 968 // If -Xshare:on is specified, print out the error message and exit VM, 969 // otherwise, set UseSharedSpaces to false and continue. 970 if (RequireSharedSpaces) { 971 vm_exit_during_initialization("Unable to use shared archive.", "Failed map_region for using -Xshare:on."); 972 } else { 973 FLAG_SET_DEFAULT(UseSharedSpaces, false); 974 } 975 return false; 976 } 977 } 978 979 // Read the miscellaneous data from the shared file, and 980 // serialize it out to its various destinations. 981 982 void MetaspaceShared::initialize_shared_spaces() { 983 FileMapInfo *mapinfo = FileMapInfo::current_info(); 984 985 char* buffer = mapinfo->region_base(md); 986 987 // Skip over (reserve space for) a list of addresses of C++ vtables 988 // for Klass objects. They get filled in later. 989 990 void** vtbl_list = (void**)buffer; 991 buffer += MetaspaceShared::vtbl_list_size * sizeof(void*); 992 Universe::init_self_patching_vtbl_list(vtbl_list, vtbl_list_size); 993 994 // Skip over (reserve space for) dummy C++ vtables Klass objects. 995 // They are used as is. 996 997 intptr_t vtable_size = *(intptr_t*)buffer; 998 buffer += sizeof(intptr_t); 999 buffer += vtable_size; 1000 1001 // Create the symbol table using the bucket array at this spot in the 1002 // misc data space. Since the symbol table is often modified, this 1003 // region (of mapped pages) will be copy-on-write. 1004 1005 int symbolTableLen = *(intptr_t*)buffer; 1006 buffer += sizeof(intptr_t); 1007 int number_of_entries = *(intptr_t*)buffer; 1008 buffer += sizeof(intptr_t); 1009 SymbolTable::create_table((HashtableBucket<mtSymbol>*)buffer, symbolTableLen, 1010 number_of_entries); 1011 buffer += symbolTableLen; 1012 1013 // Create the shared dictionary using the bucket array at this spot in 1014 // the misc data space. Since the shared dictionary table is never 1015 // modified, this region (of mapped pages) will be (effectively, if 1016 // not explicitly) read-only. 1017 1018 int sharedDictionaryLen = *(intptr_t*)buffer; 1019 buffer += sizeof(intptr_t); 1020 number_of_entries = *(intptr_t*)buffer; 1021 buffer += sizeof(intptr_t); 1022 SystemDictionary::set_shared_dictionary((HashtableBucket<mtClass>*)buffer, 1023 sharedDictionaryLen, 1024 number_of_entries); 1025 buffer += sharedDictionaryLen; 1026 1027 // Create the package info table using the bucket array at this spot in 1028 // the misc data space. Since the package info table is never 1029 // modified, this region (of mapped pages) will be (effectively, if 1030 // not explicitly) read-only. 1031 1032 int pkgInfoLen = *(intptr_t*)buffer; 1033 buffer += sizeof(intptr_t); 1034 number_of_entries = *(intptr_t*)buffer; 1035 buffer += sizeof(intptr_t); 1036 ClassLoader::create_package_info_table((HashtableBucket<mtClass>*)buffer, pkgInfoLen, 1037 number_of_entries); 1038 buffer += pkgInfoLen; 1039 ClassLoader::verify(); 1040 1041 // The following data in the shared misc data region are the linked 1042 // list elements (HashtableEntry objects) for the symbol table, string 1043 // table, and shared dictionary. The heap objects refered to by the 1044 // symbol table, string table, and shared dictionary are permanent and 1045 // unmovable. Since new entries added to the string and symbol tables 1046 // are always added at the beginning of the linked lists, THESE LINKED 1047 // LIST ELEMENTS ARE READ-ONLY. 1048 1049 int len = *(intptr_t*)buffer; // skip over symbol table entries 1050 buffer += sizeof(intptr_t); 1051 buffer += len; 1052 1053 len = *(intptr_t*)buffer; // skip over shared dictionary entries 1054 buffer += sizeof(intptr_t); 1055 buffer += len; 1056 1057 len = *(intptr_t*)buffer; // skip over package info table entries 1058 buffer += sizeof(intptr_t); 1059 buffer += len; 1060 1061 len = *(intptr_t*)buffer; // skip over package info table char[] arrays. 1062 buffer += sizeof(intptr_t); 1063 buffer += len; 1064 1065 buffer = ClassLoaderExt::restore_lookup_cache_from_archive(buffer); 1066 1067 intptr_t* array = (intptr_t*)buffer; 1068 ReadClosure rc(&array); 1069 serialize(&rc); 1070 1071 // Close the mapinfo file 1072 mapinfo->close(); 1073 1074 if (PrintSharedArchiveAndExit) { 1075 if (PrintSharedDictionary) { 1076 tty->print_cr("\nShared classes:\n"); 1077 SystemDictionary::print_shared(false); 1078 } 1079 if (_archive_loading_failed) { 1080 tty->print_cr("archive is invalid"); 1081 vm_exit(1); 1082 } else { 1083 tty->print_cr("archive is valid"); 1084 vm_exit(0); 1085 } 1086 } 1087 } 1088 1089 // JVM/TI RedefineClasses() support: 1090 bool MetaspaceShared::remap_shared_readonly_as_readwrite() { 1091 assert(SafepointSynchronize::is_at_safepoint(), "must be at safepoint"); 1092 1093 if (UseSharedSpaces) { 1094 // remap the shared readonly space to shared readwrite, private 1095 FileMapInfo* mapinfo = FileMapInfo::current_info(); 1096 if (!mapinfo->remap_shared_readonly_as_readwrite()) { 1097 return false; 1098 } 1099 } 1100 return true; 1101 } 1102 1103 int MetaspaceShared::count_class(const char* classlist_file) { 1104 if (classlist_file == NULL) { 1105 return 0; 1106 } 1107 char class_name[256]; 1108 int class_count = 0; 1109 FILE* file = fopen(classlist_file, "r"); 1110 if (file != NULL) { 1111 while ((fgets(class_name, sizeof class_name, file)) != NULL) { 1112 if (*class_name == '#') { // comment 1113 continue; 1114 } 1115 class_count++; 1116 } 1117 fclose(file); 1118 } else { 1119 char errmsg[JVM_MAXPATHLEN]; 1120 os::lasterror(errmsg, JVM_MAXPATHLEN); 1121 tty->print_cr("Loading classlist failed: %s", errmsg); 1122 exit(1); 1123 } 1124 1125 return class_count; 1126 } 1127 1128 // the sizes are good for typical large applications that have a lot of shared 1129 // classes 1130 void MetaspaceShared::estimate_regions_size() { 1131 int class_count = count_class(SharedClassListFile); 1132 class_count += count_class(ExtraSharedClassListFile); 1133 1134 if (class_count > LargeThresholdClassCount) { 1135 if (class_count < HugeThresholdClassCount) { 1136 SET_ESTIMATED_SIZE(Large, ReadOnly); 1137 SET_ESTIMATED_SIZE(Large, ReadWrite); 1138 SET_ESTIMATED_SIZE(Large, MiscData); 1139 SET_ESTIMATED_SIZE(Large, MiscCode); 1140 } else { 1141 SET_ESTIMATED_SIZE(Huge, ReadOnly); 1142 SET_ESTIMATED_SIZE(Huge, ReadWrite); 1143 SET_ESTIMATED_SIZE(Huge, MiscData); 1144 SET_ESTIMATED_SIZE(Huge, MiscCode); 1145 } 1146 } 1147 }