1 /*
   2  * Copyright (c) 2012, 2019, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  *
  23  */
  24 
  25 #include "precompiled.hpp"
  26 #include "jvm.h"
  27 #include "classfile/classLoaderDataGraph.hpp"
  28 #include "classfile/classListParser.hpp"
  29 #include "classfile/classLoaderExt.hpp"
  30 #include "classfile/dictionary.hpp"
  31 #include "classfile/loaderConstraints.hpp"
  32 #include "classfile/javaClasses.inline.hpp"
  33 #include "classfile/placeholders.hpp"
  34 #include "classfile/symbolTable.hpp"
  35 #include "classfile/stringTable.hpp"
  36 #include "classfile/systemDictionary.hpp"
  37 #include "classfile/systemDictionaryShared.hpp"
  38 #include "code/codeCache.hpp"
  39 #include "gc/shared/softRefPolicy.hpp"
  40 #include "interpreter/bytecodeStream.hpp"
  41 #include "interpreter/bytecodes.hpp"
  42 #include "logging/log.hpp"
  43 #include "logging/logMessage.hpp"
  44 #include "memory/archiveUtils.hpp"
  45 #include "memory/dynamicArchive.hpp"
  46 #include "memory/filemap.hpp"
  47 #include "memory/heapShared.inline.hpp"
  48 #include "memory/metaspace.hpp"
  49 #include "memory/metaspaceClosure.hpp"
  50 #include "memory/metaspaceShared.hpp"
  51 #include "memory/resourceArea.hpp"
  52 #include "memory/universe.hpp"
  53 #include "oops/compressedOops.inline.hpp"
  54 #include "oops/instanceClassLoaderKlass.hpp"
  55 #include "oops/instanceMirrorKlass.hpp"
  56 #include "oops/instanceRefKlass.hpp"
  57 #include "oops/methodData.hpp"
  58 #include "oops/objArrayKlass.hpp"
  59 #include "oops/objArrayOop.hpp"
  60 #include "oops/oop.inline.hpp"
  61 #include "oops/typeArrayKlass.hpp"
  62 #include "prims/jvmtiRedefineClasses.hpp"
  63 #include "runtime/handles.inline.hpp"
  64 #include "runtime/os.hpp"
  65 #include "runtime/safepointVerifiers.hpp"
  66 #include "runtime/signature.hpp"
  67 #include "runtime/timerTrace.hpp"
  68 #include "runtime/vmThread.hpp"
  69 #include "runtime/vmOperations.hpp"
  70 #include "utilities/align.hpp"
  71 #include "utilities/bitMap.inline.hpp"
  72 #include "utilities/defaultStream.hpp"
  73 #include "utilities/hashtable.inline.hpp"
  74 #if INCLUDE_G1GC
  75 #include "gc/g1/g1CollectedHeap.hpp"
  76 #endif
  77 
  78 ReservedSpace MetaspaceShared::_shared_rs;
  79 VirtualSpace MetaspaceShared::_shared_vs;
  80 MetaspaceSharedStats MetaspaceShared::_stats;
  81 bool MetaspaceShared::_has_error_classes;
  82 bool MetaspaceShared::_archive_loading_failed = false;
  83 bool MetaspaceShared::_remapped_readwrite = false;
  84 address MetaspaceShared::_i2i_entry_code_buffers = NULL;
  85 size_t MetaspaceShared::_i2i_entry_code_buffers_size = 0;
  86 void* MetaspaceShared::_shared_metaspace_static_top = NULL;
  87 intx MetaspaceShared::_mapping_delta;
  88 
  89 // The CDS archive is divided into the following regions:
  90 //     mc  - misc code (the method entry trampolines)
  91 //     rw  - read-write metadata
  92 //     ro  - read-only metadata and read-only tables
  93 //     md  - misc data (the c++ vtables)
  94 //
  95 //     ca0 - closed archive heap space #0
  96 //     ca1 - closed archive heap space #1 (may be empty)
  97 //     oa0 - open archive heap space #0
  98 //     oa1 - open archive heap space #1 (may be empty)
  99 //
 100 // The mc, rw, ro, and md regions are linearly allocated, starting from
 101 // SharedBaseAddress, in the order of mc->rw->ro->md. The size of these 4 regions
 102 // are page-aligned, and there's no gap between any consecutive regions.
 103 //
 104 // These 4 regions are populated in the following steps:
 105 // [1] All classes are loaded in MetaspaceShared::preload_classes(). All metadata are
 106 //     temporarily allocated outside of the shared regions. Only the method entry
 107 //     trampolines are written into the mc region.
 108 // [2] ArchiveCompactor copies RW metadata into the rw region.
 109 // [3] ArchiveCompactor copies RO metadata into the ro region.
 110 // [4] SymbolTable, StringTable, SystemDictionary, and a few other read-only data
 111 //     are copied into the ro region as read-only tables.
 112 // [5] C++ vtables are copied into the md region.
 113 //
 114 // The s0/s1 and oa0/oa1 regions are populated inside HeapShared::archive_java_heap_objects.
 115 // Their layout is independent of the other 4 regions.
 116 
 117 char* DumpRegion::expand_top_to(char* newtop) {
 118   assert(is_allocatable(), "must be initialized and not packed");
 119   assert(newtop >= _top, "must not grow backwards");
 120   if (newtop > _end) {
 121     MetaspaceShared::report_out_of_space(_name, newtop - _top);
 122     ShouldNotReachHere();
 123   }
 124   uintx delta;
 125   if (DynamicDumpSharedSpaces) {
 126     delta = DynamicArchive::object_delta_uintx(newtop);
 127   } else {
 128     delta = MetaspaceShared::object_delta_uintx(newtop);
 129   }
 130   if (delta > MAX_SHARED_DELTA) {
 131     // This is just a sanity check and should not appear in any real world usage. This
 132     // happens only if you allocate more than 2GB of shared objects and would require
 133     // millions of shared classes.
 134     vm_exit_during_initialization("Out of memory in the CDS archive",
 135                                   "Please reduce the number of shared classes.");
 136   }
 137 
 138   MetaspaceShared::commit_shared_space_to(newtop);
 139   _top = newtop;
 140   return _top;
 141 }
 142 
 143 char* DumpRegion::allocate(size_t num_bytes, size_t alignment) {
 144   char* p = (char*)align_up(_top, alignment);
 145   char* newtop = p + align_up(num_bytes, alignment);
 146   expand_top_to(newtop);
 147   memset(p, 0, newtop - p);
 148   return p;
 149 }
 150 
 151 void DumpRegion::append_intptr_t(intptr_t n, bool need_to_mark) {
 152   assert(is_aligned(_top, sizeof(intptr_t)), "bad alignment");
 153   intptr_t *p = (intptr_t*)_top;
 154   char* newtop = _top + sizeof(intptr_t);
 155   expand_top_to(newtop);
 156   *p = n;
 157   if (need_to_mark) {
 158     ArchivePtrMarker::mark_pointer(p);
 159   }
 160 }
 161 
 162 void DumpRegion::print(size_t total_bytes) const {
 163   tty->print_cr("%-3s space: " SIZE_FORMAT_W(9) " [ %4.1f%% of total] out of " SIZE_FORMAT_W(9) " bytes [%5.1f%% used] at " INTPTR_FORMAT,
 164                 _name, used(), percent_of(used(), total_bytes), reserved(), percent_of(used(), reserved()),
 165                 p2i(_base + MetaspaceShared::final_delta()));
 166 }
 167 
 168 void DumpRegion::print_out_of_space_msg(const char* failing_region, size_t needed_bytes) {
 169   tty->print("[%-8s] " PTR_FORMAT " - " PTR_FORMAT " capacity =%9d, allocated =%9d",
 170              _name, p2i(_base), p2i(_top), int(_end - _base), int(_top - _base));
 171   if (strcmp(_name, failing_region) == 0) {
 172     tty->print_cr(" required = %d", int(needed_bytes));
 173   } else {
 174     tty->cr();
 175   }
 176 }
 177 
 178 void DumpRegion::pack(DumpRegion* next) {
 179   assert(!is_packed(), "sanity");
 180   _end = (char*)align_up(_top, Metaspace::reserve_alignment());
 181   _is_packed = true;
 182   if (next != NULL) {
 183     next->_base = next->_top = this->_end;
 184     next->_end = MetaspaceShared::shared_rs()->end();
 185   }
 186 }
 187 
 188 static DumpRegion _mc_region("mc"), _ro_region("ro"), _rw_region("rw"), _md_region("md");
 189 static size_t _total_closed_archive_region_size = 0, _total_open_archive_region_size = 0;
 190 
 191 void MetaspaceShared::init_shared_dump_space(DumpRegion* first_space, address first_space_bottom) {
 192   // Start with 0 committed bytes. The memory will be committed as needed by
 193   // MetaspaceShared::commit_shared_space_to().
 194   if (!_shared_vs.initialize(_shared_rs, 0)) {
 195     fatal("Unable to allocate memory for shared space");
 196   }
 197   first_space->init(&_shared_rs, (char*)first_space_bottom);
 198 }
 199 
 200 DumpRegion* MetaspaceShared::misc_code_dump_space() {
 201   return &_mc_region;
 202 }
 203 
 204 DumpRegion* MetaspaceShared::read_write_dump_space() {
 205   return &_rw_region;
 206 }
 207 
 208 DumpRegion* MetaspaceShared::read_only_dump_space() {
 209   return &_ro_region;
 210 }
 211 
 212 void MetaspaceShared::pack_dump_space(DumpRegion* current, DumpRegion* next,
 213                                       ReservedSpace* rs) {
 214   current->pack(next);
 215 }
 216 
 217 char* MetaspaceShared::misc_code_space_alloc(size_t num_bytes) {
 218   return _mc_region.allocate(num_bytes);
 219 }
 220 
 221 char* MetaspaceShared::read_only_space_alloc(size_t num_bytes) {
 222   return _ro_region.allocate(num_bytes);
 223 }
 224 
 225 // When reserving an address range using ReservedSpace, we need an alignment that satisfies both:
 226 // os::vm_allocation_granularity() -- so that we can sub-divide this range into multiple mmap regions,
 227 //                                    while keeping the first range at offset 0 of this range.
 228 // Metaspace::reserve_alignment()  -- so we can pass the region to
 229 //                                    Metaspace::allocate_metaspace_compressed_klass_ptrs.
 230 size_t MetaspaceShared::reserved_space_alignment() {
 231   size_t os_align = os::vm_allocation_granularity();
 232   size_t ms_align = Metaspace::reserve_alignment();
 233   if (os_align >= ms_align) {
 234     assert(os_align % ms_align == 0, "must be a multiple");
 235     return os_align;
 236   } else {
 237     assert(ms_align % os_align == 0, "must be a multiple");
 238     return ms_align;
 239   }
 240 }
 241 
 242 ReservedSpace MetaspaceShared::reserve_shared_space(size_t size, char* requested_address) {
 243   bool large_pages = false; // Don't use large pages for the CDS archive.
 244   assert(is_aligned(requested_address, reserved_space_alignment()), "must be");
 245   return ReservedSpace(size, reserved_space_alignment(), large_pages, requested_address);
 246 }
 247 
 248 void MetaspaceShared::initialize_dumptime_shared_and_meta_spaces() {
 249   assert(DumpSharedSpaces, "should be called for dump time only");
 250   const size_t reserve_alignment = reserved_space_alignment();
 251   char* shared_base = (char*)align_up((char*)SharedBaseAddress, reserve_alignment);
 252 
 253 #ifdef _LP64
 254   // On 64-bit VM, the heap and class space layout will be the same as if
 255   // you're running in -Xshare:on mode:
 256   //
 257   //                              +-- SharedBaseAddress (default = 0x800000000)
 258   //                              v
 259   // +-..---------+---------+ ... +----+----+----+----+---------------+
 260   // |    Heap    | Archive |     | MC | RW | RO | MD | class space   |
 261   // +-..---------+---------+ ... +----+----+----+----+---------------+
 262   // |<--   MaxHeapSize  -->|     |<-- UnscaledClassSpaceMax = 4GB -->|
 263   //
 264   const uint64_t UnscaledClassSpaceMax = (uint64_t(max_juint) + 1);
 265   const size_t cds_total = align_down(UnscaledClassSpaceMax, reserve_alignment);
 266 #else
 267   // We don't support archives larger than 256MB on 32-bit due to limited virtual address space.
 268   size_t cds_total = align_down(256*M, reserve_alignment);
 269 #endif
 270 
 271   bool use_requested_base = true;
 272   DEBUG_ONLY(
 273     if (SharedBaseAddress == 0) {
 274       log_info(cds)("SharedBaseAddress == 0: always allocate class space at an alternative address");
 275       use_requested_base = false;
 276     })
 277 
 278   // First try to reserve the space at the specified SharedBaseAddress.
 279   assert(!_shared_rs.is_reserved(), "must be");
 280   if (use_requested_base) {
 281     _shared_rs = reserve_shared_space(cds_total, shared_base);
 282   }
 283   if (_shared_rs.is_reserved()) {
 284     assert(shared_base == 0 || _shared_rs.base() == shared_base, "should match");
 285   } else {
 286     // Get a mmap region anywhere if the SharedBaseAddress fails.
 287     _shared_rs = reserve_shared_space(cds_total);
 288   }
 289   if (!_shared_rs.is_reserved()) {
 290     vm_exit_during_initialization("Unable to reserve memory for shared space",
 291                                   err_msg(SIZE_FORMAT " bytes.", cds_total));
 292   }
 293 
 294 #ifdef _LP64
 295   // During dump time, we allocate 4GB (UnscaledClassSpaceMax) of space and split it up:
 296   // + The upper 1 GB is used as the "temporary compressed class space" -- preload_classes()
 297   //   will store Klasses into this space.
 298   // + The lower 3 GB is used for the archive -- when preload_classes() is done,
 299   //   ArchiveCompactor will copy the class metadata into this space, first the RW parts,
 300   //   then the RO parts.
 301 
 302   assert(UseCompressedOops && UseCompressedClassPointers,
 303       "UseCompressedOops and UseCompressedClassPointers must be set");
 304 
 305   size_t max_archive_size = align_down(cds_total * 3 / 4, reserve_alignment);
 306   ReservedSpace tmp_class_space = _shared_rs.last_part(max_archive_size);
 307   CompressedClassSpaceSize = align_down(tmp_class_space.size(), reserve_alignment);
 308   _shared_rs = _shared_rs.first_part(max_archive_size);
 309 
 310   // Set up compress class pointers.
 311   CompressedKlassPointers::set_base((address)_shared_rs.base());
 312   // Set narrow_klass_shift to be LogKlassAlignmentInBytes. This is consistent
 313   // with AOT.
 314   CompressedKlassPointers::set_shift(LogKlassAlignmentInBytes);
 315   // Set the range of klass addresses to 4GB.
 316   CompressedKlassPointers::set_range(cds_total);
 317 
 318   Metaspace::initialize_class_space(tmp_class_space);
 319   log_info(cds)("narrow_klass_base = " PTR_FORMAT ", narrow_klass_shift = %d",
 320                 p2i(CompressedKlassPointers::base()), CompressedKlassPointers::shift());
 321 
 322   log_info(cds)("Allocated temporary class space: " SIZE_FORMAT " bytes at " PTR_FORMAT,
 323                 CompressedClassSpaceSize, p2i(tmp_class_space.base()));
 324 #endif
 325 
 326   init_shared_dump_space(&_mc_region);
 327   SharedBaseAddress = (size_t)_shared_rs.base();
 328   tty->print_cr("Allocated shared space: " SIZE_FORMAT " bytes at " PTR_FORMAT,
 329                 _shared_rs.size(), p2i(_shared_rs.base()));
 330 }
 331 
 332 // Called by universe_post_init()
 333 void MetaspaceShared::post_initialize(TRAPS) {
 334   if (UseSharedSpaces) {
 335     int size = FileMapInfo::get_number_of_shared_paths();
 336     if (size > 0) {
 337       SystemDictionaryShared::allocate_shared_data_arrays(size, THREAD);
 338       if (!DynamicDumpSharedSpaces) {
 339         FileMapInfo* info;
 340         if (FileMapInfo::dynamic_info() == NULL) {
 341           info = FileMapInfo::current_info();
 342         } else {
 343           info = FileMapInfo::dynamic_info();
 344         }
 345         ClassLoaderExt::init_paths_start_index(info->app_class_paths_start_index());
 346         ClassLoaderExt::init_app_module_paths_start_index(info->app_module_paths_start_index());
 347       }
 348     }
 349   }
 350 }
 351 
 352 static GrowableArray<Handle>* _extra_interned_strings = NULL;
 353 
 354 void MetaspaceShared::read_extra_data(const char* filename, TRAPS) {
 355   _extra_interned_strings = new (ResourceObj::C_HEAP, mtInternal)GrowableArray<Handle>(10000, true);
 356 
 357   HashtableTextDump reader(filename);
 358   reader.check_version("VERSION: 1.0");
 359 
 360   while (reader.remain() > 0) {
 361     int utf8_length;
 362     int prefix_type = reader.scan_prefix(&utf8_length);
 363     ResourceMark rm(THREAD);
 364     if (utf8_length == 0x7fffffff) {
 365       // buf_len will overflown 32-bit value.
 366       vm_exit_during_initialization(err_msg("string length too large: %d", utf8_length));
 367     }
 368     int buf_len = utf8_length+1;
 369     char* utf8_buffer = NEW_RESOURCE_ARRAY(char, buf_len);
 370     reader.get_utf8(utf8_buffer, utf8_length);
 371     utf8_buffer[utf8_length] = '\0';
 372 
 373     if (prefix_type == HashtableTextDump::SymbolPrefix) {
 374       SymbolTable::new_permanent_symbol(utf8_buffer);
 375     } else{
 376       assert(prefix_type == HashtableTextDump::StringPrefix, "Sanity");
 377       oop s = StringTable::intern(utf8_buffer, THREAD);
 378 
 379       if (HAS_PENDING_EXCEPTION) {
 380         log_warning(cds, heap)("[line %d] extra interned string allocation failed; size too large: %d",
 381                                reader.last_line_no(), utf8_length);
 382         CLEAR_PENDING_EXCEPTION;
 383       } else {
 384 #if INCLUDE_G1GC
 385         if (UseG1GC) {
 386           typeArrayOop body = java_lang_String::value(s);
 387           const HeapRegion* hr = G1CollectedHeap::heap()->heap_region_containing(body);
 388           if (hr->is_humongous()) {
 389             // Don't keep it alive, so it will be GC'ed before we dump the strings, in order
 390             // to maximize free heap space and minimize fragmentation.
 391             log_warning(cds, heap)("[line %d] extra interned string ignored; size too large: %d",
 392                                 reader.last_line_no(), utf8_length);
 393             continue;
 394           }
 395         }
 396 #endif
 397         // Interned strings are GC'ed if there are no references to it, so let's
 398         // add a reference to keep this string alive.
 399         assert(s != NULL, "must succeed");
 400         Handle h(THREAD, s);
 401         _extra_interned_strings->append(h);
 402       }
 403     }
 404   }
 405 }
 406 
 407 void MetaspaceShared::commit_shared_space_to(char* newtop) {
 408   Arguments::assert_is_dumping_archive();
 409   char* base = _shared_rs.base();
 410   size_t need_committed_size = newtop - base;
 411   size_t has_committed_size = _shared_vs.committed_size();
 412   if (need_committed_size < has_committed_size) {
 413     return;
 414   }
 415 
 416   size_t min_bytes = need_committed_size - has_committed_size;
 417   size_t preferred_bytes = 1 * M;
 418   size_t uncommitted = _shared_vs.reserved_size() - has_committed_size;
 419 
 420   size_t commit =MAX2(min_bytes, preferred_bytes);
 421   commit = MIN2(commit, uncommitted);
 422   assert(commit <= uncommitted, "sanity");
 423 
 424   bool result = _shared_vs.expand_by(commit, false);
 425   ArchivePtrMarker::expand_ptr_end((address*)_shared_vs.high());
 426 
 427   if (!result) {
 428     vm_exit_during_initialization(err_msg("Failed to expand shared space to " SIZE_FORMAT " bytes",
 429                                           need_committed_size));
 430   }
 431 
 432   log_info(cds)("Expanding shared spaces by " SIZE_FORMAT_W(7) " bytes [total " SIZE_FORMAT_W(9)  " bytes ending at %p]",
 433                 commit, _shared_vs.actual_committed_size(), _shared_vs.high());
 434 }
 435 
 436 void MetaspaceShared::initialize_ptr_marker(CHeapBitMap* ptrmap) {
 437   ArchivePtrMarker::initialize(ptrmap, (address*)_shared_vs.low(), (address*)_shared_vs.high());
 438 }
 439 
 440 // Read/write a data stream for restoring/preserving metadata pointers and
 441 // miscellaneous data from/to the shared archive file.
 442 
 443 void MetaspaceShared::serialize(SerializeClosure* soc) {
 444   int tag = 0;
 445   soc->do_tag(--tag);
 446 
 447   // Verify the sizes of various metadata in the system.
 448   soc->do_tag(sizeof(Method));
 449   soc->do_tag(sizeof(ConstMethod));
 450   soc->do_tag(arrayOopDesc::base_offset_in_bytes(T_BYTE));
 451   soc->do_tag(sizeof(ConstantPool));
 452   soc->do_tag(sizeof(ConstantPoolCache));
 453   soc->do_tag(objArrayOopDesc::base_offset_in_bytes());
 454   soc->do_tag(typeArrayOopDesc::base_offset_in_bytes(T_BYTE));
 455   soc->do_tag(sizeof(Symbol));
 456 
 457   // Dump/restore miscellaneous metadata.
 458   JavaClasses::serialize_offsets(soc);
 459   Universe::serialize(soc);
 460   soc->do_tag(--tag);
 461 
 462   // Dump/restore references to commonly used names and signatures.
 463   vmSymbols::serialize(soc);
 464   soc->do_tag(--tag);
 465 
 466   // Dump/restore the symbol/string/subgraph_info tables
 467   SymbolTable::serialize_shared_table_header(soc);
 468   StringTable::serialize_shared_table_header(soc);
 469   HeapShared::serialize_subgraph_info_table_header(soc);
 470   SystemDictionaryShared::serialize_dictionary_headers(soc);
 471 
 472   InstanceMirrorKlass::serialize_offsets(soc);
 473   soc->do_tag(--tag);
 474 
 475   serialize_cloned_cpp_vtptrs(soc);
 476   soc->do_tag(--tag);
 477 
 478   soc->do_tag(666);
 479 }
 480 
 481 address MetaspaceShared::i2i_entry_code_buffers(size_t total_size) {
 482   if (DumpSharedSpaces) {
 483     if (_i2i_entry_code_buffers == NULL) {
 484       _i2i_entry_code_buffers = (address)misc_code_space_alloc(total_size);
 485       _i2i_entry_code_buffers_size = total_size;
 486     }
 487   } else if (UseSharedSpaces) {
 488     assert(_i2i_entry_code_buffers != NULL, "must already been initialized");
 489   } else {
 490     return NULL;
 491   }
 492 
 493   assert(_i2i_entry_code_buffers_size == total_size, "must not change");
 494   return _i2i_entry_code_buffers;
 495 }
 496 
 497 uintx MetaspaceShared::object_delta_uintx(void* obj) {
 498   Arguments::assert_is_dumping_archive();
 499   if (DumpSharedSpaces) {
 500     assert(shared_rs()->contains(obj), "must be");
 501   } else {
 502     assert(is_in_shared_metaspace(obj) || DynamicArchive::is_in_target_space(obj), "must be");
 503   }
 504   address base_address = address(SharedBaseAddress);
 505   uintx deltax = address(obj) - base_address;
 506   return deltax;
 507 }
 508 
 509 // Global object for holding classes that have been loaded.  Since this
 510 // is run at a safepoint just before exit, this is the entire set of classes.
 511 static GrowableArray<Klass*>* _global_klass_objects;
 512 
 513 GrowableArray<Klass*>* MetaspaceShared::collected_klasses() {
 514   return _global_klass_objects;
 515 }
 516 
 517 static void collect_array_classes(Klass* k) {
 518   _global_klass_objects->append_if_missing(k);
 519   if (k->is_array_klass()) {
 520     // Add in the array classes too
 521     ArrayKlass* ak = ArrayKlass::cast(k);
 522     Klass* h = ak->higher_dimension();
 523     if (h != NULL) {
 524       h->array_klasses_do(collect_array_classes);
 525     }
 526   }
 527 }
 528 
 529 class CollectClassesClosure : public KlassClosure {
 530   void do_klass(Klass* k) {
 531     if (k->is_instance_klass() &&
 532         SystemDictionaryShared::is_excluded_class(InstanceKlass::cast(k))) {
 533       // Don't add to the _global_klass_objects
 534     } else {
 535       _global_klass_objects->append_if_missing(k);
 536     }
 537     if (k->is_array_klass()) {
 538       // Add in the array classes too
 539       ArrayKlass* ak = ArrayKlass::cast(k);
 540       Klass* h = ak->higher_dimension();
 541       if (h != NULL) {
 542         h->array_klasses_do(collect_array_classes);
 543       }
 544     }
 545   }
 546 };
 547 
 548 static void remove_unshareable_in_classes() {
 549   for (int i = 0; i < _global_klass_objects->length(); i++) {
 550     Klass* k = _global_klass_objects->at(i);
 551     if (!k->is_objArray_klass()) {
 552       // InstanceKlass and TypeArrayKlass will in turn call remove_unshareable_info
 553       // on their array classes.
 554       assert(k->is_instance_klass() || k->is_typeArray_klass(), "must be");
 555       k->remove_unshareable_info();
 556     }
 557   }
 558 }
 559 
 560 static void remove_java_mirror_in_classes() {
 561   for (int i = 0; i < _global_klass_objects->length(); i++) {
 562     Klass* k = _global_klass_objects->at(i);
 563     if (!k->is_objArray_klass()) {
 564       // InstanceKlass and TypeArrayKlass will in turn call remove_unshareable_info
 565       // on their array classes.
 566       assert(k->is_instance_klass() || k->is_typeArray_klass(), "must be");
 567       k->remove_java_mirror();
 568     }
 569   }
 570 }
 571 
 572 static void clear_basic_type_mirrors() {
 573   assert(!HeapShared::is_heap_object_archiving_allowed(), "Sanity");
 574   Universe::set_int_mirror(NULL);
 575   Universe::set_float_mirror(NULL);
 576   Universe::set_double_mirror(NULL);
 577   Universe::set_byte_mirror(NULL);
 578   Universe::set_bool_mirror(NULL);
 579   Universe::set_char_mirror(NULL);
 580   Universe::set_long_mirror(NULL);
 581   Universe::set_short_mirror(NULL);
 582   Universe::set_void_mirror(NULL);
 583 }
 584 
 585 static void rewrite_nofast_bytecode(Method* method) {
 586   BytecodeStream bcs(method);
 587   while (!bcs.is_last_bytecode()) {
 588     Bytecodes::Code opcode = bcs.next();
 589     switch (opcode) {
 590     case Bytecodes::_getfield:      *bcs.bcp() = Bytecodes::_nofast_getfield;      break;
 591     case Bytecodes::_putfield:      *bcs.bcp() = Bytecodes::_nofast_putfield;      break;
 592     case Bytecodes::_aload_0:       *bcs.bcp() = Bytecodes::_nofast_aload_0;       break;
 593     case Bytecodes::_iload: {
 594       if (!bcs.is_wide()) {
 595         *bcs.bcp() = Bytecodes::_nofast_iload;
 596       }
 597       break;
 598     }
 599     default: break;
 600     }
 601   }
 602 }
 603 
 604 // Walk all methods in the class list to ensure that they won't be modified at
 605 // run time. This includes:
 606 // [1] Rewrite all bytecodes as needed, so that the ConstMethod* will not be modified
 607 //     at run time by RewriteBytecodes/RewriteFrequentPairs
 608 // [2] Assign a fingerprint, so one doesn't need to be assigned at run-time.
 609 static void rewrite_nofast_bytecodes_and_calculate_fingerprints() {
 610   for (int i = 0; i < _global_klass_objects->length(); i++) {
 611     Klass* k = _global_klass_objects->at(i);
 612     if (k->is_instance_klass()) {
 613       InstanceKlass* ik = InstanceKlass::cast(k);
 614       MetaspaceShared::rewrite_nofast_bytecodes_and_calculate_fingerprints(ik);
 615     }
 616   }
 617 }
 618 
 619 void MetaspaceShared::rewrite_nofast_bytecodes_and_calculate_fingerprints(InstanceKlass* ik) {
 620   for (int i = 0; i < ik->methods()->length(); i++) {
 621     Method* m = ik->methods()->at(i);
 622     rewrite_nofast_bytecode(m);
 623     Fingerprinter fp(m);
 624     // The side effect of this call sets method's fingerprint field.
 625     fp.fingerprint();
 626   }
 627 }
 628 
 629 // Objects of the Metadata types (such as Klass and ConstantPool) have C++ vtables.
 630 // (In GCC this is the field <Type>::_vptr, i.e., first word in the object.)
 631 //
 632 // Addresses of the vtables and the methods may be different across JVM runs,
 633 // if libjvm.so is dynamically loaded at a different base address.
 634 //
 635 // To ensure that the Metadata objects in the CDS archive always have the correct vtable:
 636 //
 637 // + at dump time:  we redirect the _vptr to point to our own vtables inside
 638 //                  the CDS image
 639 // + at run time:   we clone the actual contents of the vtables from libjvm.so
 640 //                  into our own tables.
 641 
 642 // Currently, the archive contain ONLY the following types of objects that have C++ vtables.
 643 #define CPP_VTABLE_PATCH_TYPES_DO(f) \
 644   f(ConstantPool) \
 645   f(InstanceKlass) \
 646   f(InstanceClassLoaderKlass) \
 647   f(InstanceMirrorKlass) \
 648   f(InstanceRefKlass) \
 649   f(Method) \
 650   f(ObjArrayKlass) \
 651   f(TypeArrayKlass)
 652 
 653 class CppVtableInfo {
 654   intptr_t _vtable_size;
 655   intptr_t _cloned_vtable[1];
 656 public:
 657   static int num_slots(int vtable_size) {
 658     return 1 + vtable_size; // Need to add the space occupied by _vtable_size;
 659   }
 660   int vtable_size()           { return int(uintx(_vtable_size)); }
 661   void set_vtable_size(int n) { _vtable_size = intptr_t(n); }
 662   intptr_t* cloned_vtable()   { return &_cloned_vtable[0]; }
 663   void zero()                 { memset(_cloned_vtable, 0, sizeof(intptr_t) * vtable_size()); }
 664   // Returns the address of the next CppVtableInfo that can be placed immediately after this CppVtableInfo
 665   static size_t byte_size(int vtable_size) {
 666     CppVtableInfo i;
 667     return pointer_delta(&i._cloned_vtable[vtable_size], &i, sizeof(u1));
 668   }
 669 };
 670 
 671 template <class T> class CppVtableCloner : public T {
 672   static intptr_t* vtable_of(Metadata& m) {
 673     return *((intptr_t**)&m);
 674   }
 675   static CppVtableInfo* _info;
 676 
 677   static int get_vtable_length(const char* name);
 678 
 679 public:
 680   // Allocate and initialize the C++ vtable, starting from top, but do not go past end.
 681   static intptr_t* allocate(const char* name);
 682 
 683   // Clone the vtable to ...
 684   static intptr_t* clone_vtable(const char* name, CppVtableInfo* info);
 685 
 686   static void zero_vtable_clone() {
 687     assert(DumpSharedSpaces, "dump-time only");
 688     _info->zero();
 689   }
 690 
 691   // Switch the vtable pointer to point to the cloned vtable.
 692   static void patch(Metadata* obj) {
 693     assert(DumpSharedSpaces, "dump-time only");
 694     assert(MetaspaceShared::is_in_output_space(obj), "must be");
 695     *(void**)obj = (void*)(_info->cloned_vtable());
 696     ArchivePtrMarker::mark_pointer(obj);
 697   }
 698 
 699   static bool is_valid_shared_object(const T* obj) {
 700     intptr_t* vptr = *(intptr_t**)obj;
 701     return vptr == _info->cloned_vtable();
 702   }
 703 };
 704 
 705 template <class T> CppVtableInfo* CppVtableCloner<T>::_info = NULL;
 706 
 707 template <class T>
 708 intptr_t* CppVtableCloner<T>::allocate(const char* name) {
 709   assert(is_aligned(_md_region.top(), sizeof(intptr_t)), "bad alignment");
 710   int n = get_vtable_length(name);
 711   _info = (CppVtableInfo*)_md_region.allocate(CppVtableInfo::byte_size(n), sizeof(intptr_t));
 712   _info->set_vtable_size(n);
 713 
 714   intptr_t* p = clone_vtable(name, _info);
 715   assert((char*)p == _md_region.top(), "must be");
 716 
 717   return _info->cloned_vtable();
 718 }
 719 
 720 template <class T>
 721 intptr_t* CppVtableCloner<T>::clone_vtable(const char* name, CppVtableInfo* info) {
 722   if (!DumpSharedSpaces) {
 723     assert(_info == 0, "_info is initialized only at dump time");
 724     _info = info; // Remember it -- it will be used by MetaspaceShared::is_valid_shared_method()
 725   }
 726   T tmp; // Allocate temporary dummy metadata object to get to the original vtable.
 727   int n = info->vtable_size();
 728   intptr_t* srcvtable = vtable_of(tmp);
 729   intptr_t* dstvtable = info->cloned_vtable();
 730 
 731   // We already checked (and, if necessary, adjusted n) when the vtables were allocated, so we are
 732   // safe to do memcpy.
 733   log_debug(cds, vtables)("Copying %3d vtable entries for %s", n, name);
 734   memcpy(dstvtable, srcvtable, sizeof(intptr_t) * n);
 735   return dstvtable + n;
 736 }
 737 
 738 // To determine the size of the vtable for each type, we use the following
 739 // trick by declaring 2 subclasses:
 740 //
 741 //   class CppVtableTesterA: public InstanceKlass {virtual int   last_virtual_method() {return 1;}    };
 742 //   class CppVtableTesterB: public InstanceKlass {virtual void* last_virtual_method() {return NULL}; };
 743 //
 744 // CppVtableTesterA and CppVtableTesterB's vtables have the following properties:
 745 // - Their size (N+1) is exactly one more than the size of InstanceKlass's vtable (N)
 746 // - The first N entries have are exactly the same as in InstanceKlass's vtable.
 747 // - Their last entry is different.
 748 //
 749 // So to determine the value of N, we just walk CppVtableTesterA and CppVtableTesterB's tables
 750 // and find the first entry that's different.
 751 //
 752 // This works on all C++ compilers supported by Oracle, but you may need to tweak it for more
 753 // esoteric compilers.
 754 
 755 template <class T> class CppVtableTesterB: public T {
 756 public:
 757   virtual int last_virtual_method() {return 1;}
 758 };
 759 
 760 template <class T> class CppVtableTesterA : public T {
 761 public:
 762   virtual void* last_virtual_method() {
 763     // Make this different than CppVtableTesterB::last_virtual_method so the C++
 764     // compiler/linker won't alias the two functions.
 765     return NULL;
 766   }
 767 };
 768 
 769 template <class T>
 770 int CppVtableCloner<T>::get_vtable_length(const char* name) {
 771   CppVtableTesterA<T> a;
 772   CppVtableTesterB<T> b;
 773 
 774   intptr_t* avtable = vtable_of(a);
 775   intptr_t* bvtable = vtable_of(b);
 776 
 777   // Start at slot 1, because slot 0 may be RTTI (on Solaris/Sparc)
 778   int vtable_len = 1;
 779   for (; ; vtable_len++) {
 780     if (avtable[vtable_len] != bvtable[vtable_len]) {
 781       break;
 782     }
 783   }
 784   log_debug(cds, vtables)("Found   %3d vtable entries for %s", vtable_len, name);
 785 
 786   return vtable_len;
 787 }
 788 
 789 #define ALLOC_CPP_VTABLE_CLONE(c) \
 790   _cloned_cpp_vtptrs[c##_Kind] = CppVtableCloner<c>::allocate(#c); \
 791   ArchivePtrMarker::mark_pointer(&_cloned_cpp_vtptrs[c##_Kind]);
 792 
 793 #define CLONE_CPP_VTABLE(c) \
 794   p = CppVtableCloner<c>::clone_vtable(#c, (CppVtableInfo*)p);
 795 
 796 #define ZERO_CPP_VTABLE(c) \
 797  CppVtableCloner<c>::zero_vtable_clone();
 798 
 799 //------------------------------ for DynamicDumpSharedSpaces - start
 800 #define DECLARE_CLONED_VTABLE_KIND(c) c ## _Kind,
 801 
 802 enum {
 803   CPP_VTABLE_PATCH_TYPES_DO(DECLARE_CLONED_VTABLE_KIND)
 804   _num_cloned_vtable_kinds
 805 };
 806 
 807 static intptr_t** _cloned_cpp_vtptrs = NULL;
 808 
 809 void MetaspaceShared::serialize_cloned_cpp_vtptrs(SerializeClosure* soc) {
 810   soc->do_ptr((void**)&_cloned_cpp_vtptrs);
 811 }
 812 
 813 intptr_t* MetaspaceShared::fix_cpp_vtable_for_dynamic_archive(MetaspaceObj::Type msotype, address obj) {
 814   assert(DynamicDumpSharedSpaces, "must");
 815   int kind = -1;
 816   switch (msotype) {
 817   case MetaspaceObj::SymbolType:
 818   case MetaspaceObj::TypeArrayU1Type:
 819   case MetaspaceObj::TypeArrayU2Type:
 820   case MetaspaceObj::TypeArrayU4Type:
 821   case MetaspaceObj::TypeArrayU8Type:
 822   case MetaspaceObj::TypeArrayOtherType:
 823   case MetaspaceObj::ConstMethodType:
 824   case MetaspaceObj::ConstantPoolCacheType:
 825   case MetaspaceObj::AnnotationsType:
 826   case MetaspaceObj::MethodCountersType:
 827     // These have no vtables.
 828     break;
 829   case MetaspaceObj::ClassType:
 830     {
 831       Klass* k = (Klass*)obj;
 832       assert(k->is_klass(), "must be");
 833       if (k->is_instance_klass()) {
 834         kind = InstanceKlass_Kind;
 835       } else {
 836         assert(k->is_objArray_klass(),
 837                "We shouldn't archive any other klasses in DynamicDumpSharedSpaces");
 838         kind = ObjArrayKlass_Kind;
 839       }
 840     }
 841     break;
 842 
 843   case MetaspaceObj::MethodType:
 844     {
 845       Method* m = (Method*)obj;
 846       assert(m->is_method(), "must be");
 847       kind = Method_Kind;
 848     }
 849     break;
 850 
 851   case MetaspaceObj::MethodDataType:
 852     // We don't archive MethodData <-- should have been removed in removed_unsharable_info
 853     ShouldNotReachHere();
 854     break;
 855 
 856   case MetaspaceObj::ConstantPoolType:
 857     {
 858       ConstantPool *cp = (ConstantPool*)obj;
 859       assert(cp->is_constantPool(), "must be");
 860       kind = ConstantPool_Kind;
 861     }
 862     break;
 863 
 864   default:
 865     ShouldNotReachHere();
 866   }
 867 
 868   if (kind >= 0) {
 869     assert(kind < _num_cloned_vtable_kinds, "must be");
 870     return _cloned_cpp_vtptrs[kind];
 871   } else {
 872     return NULL;
 873   }
 874 }
 875 
 876 //------------------------------ for DynamicDumpSharedSpaces - end
 877 
 878 // This can be called at both dump time and run time.
 879 intptr_t* MetaspaceShared::clone_cpp_vtables(intptr_t* p) {
 880   assert(DumpSharedSpaces || UseSharedSpaces, "sanity");
 881   CPP_VTABLE_PATCH_TYPES_DO(CLONE_CPP_VTABLE);
 882   return p;
 883 }
 884 
 885 void MetaspaceShared::zero_cpp_vtable_clones_for_writing() {
 886   assert(DumpSharedSpaces, "dump-time only");
 887   CPP_VTABLE_PATCH_TYPES_DO(ZERO_CPP_VTABLE);
 888 }
 889 
 890 // Allocate and initialize the C++ vtables, starting from top, but do not go past end.
 891 void MetaspaceShared::allocate_cpp_vtable_clones() {
 892   assert(DumpSharedSpaces, "dump-time only");
 893   // Layout (each slot is a intptr_t):
 894   //   [number of slots in the first vtable = n1]
 895   //   [ <n1> slots for the first vtable]
 896   //   [number of slots in the first second = n2]
 897   //   [ <n2> slots for the second vtable]
 898   //   ...
 899   // The order of the vtables is the same as the CPP_VTAB_PATCH_TYPES_DO macro.
 900   CPP_VTABLE_PATCH_TYPES_DO(ALLOC_CPP_VTABLE_CLONE);
 901 }
 902 
 903 // Switch the vtable pointer to point to the cloned vtable. We assume the
 904 // vtable pointer is in first slot in object.
 905 void MetaspaceShared::patch_cpp_vtable_pointers() {
 906   int n = _global_klass_objects->length();
 907   for (int i = 0; i < n; i++) {
 908     Klass* obj = _global_klass_objects->at(i);
 909     if (obj->is_instance_klass()) {
 910       InstanceKlass* ik = InstanceKlass::cast(obj);
 911       if (ik->is_class_loader_instance_klass()) {
 912         CppVtableCloner<InstanceClassLoaderKlass>::patch(ik);
 913       } else if (ik->is_reference_instance_klass()) {
 914         CppVtableCloner<InstanceRefKlass>::patch(ik);
 915       } else if (ik->is_mirror_instance_klass()) {
 916         CppVtableCloner<InstanceMirrorKlass>::patch(ik);
 917       } else {
 918         CppVtableCloner<InstanceKlass>::patch(ik);
 919       }
 920       ConstantPool* cp = ik->constants();
 921       CppVtableCloner<ConstantPool>::patch(cp);
 922       for (int j = 0; j < ik->methods()->length(); j++) {
 923         Method* m = ik->methods()->at(j);
 924         CppVtableCloner<Method>::patch(m);
 925         assert(CppVtableCloner<Method>::is_valid_shared_object(m), "must be");
 926       }
 927     } else if (obj->is_objArray_klass()) {
 928       CppVtableCloner<ObjArrayKlass>::patch(obj);
 929     } else {
 930       assert(obj->is_typeArray_klass(), "sanity");
 931       CppVtableCloner<TypeArrayKlass>::patch(obj);
 932     }
 933   }
 934 }
 935 
 936 bool MetaspaceShared::is_valid_shared_method(const Method* m) {
 937   assert(is_in_shared_metaspace(m), "must be");
 938   return CppVtableCloner<Method>::is_valid_shared_object(m);
 939 }
 940 
 941 void WriteClosure::do_oop(oop* o) {
 942   if (*o == NULL) {
 943     _dump_region->append_intptr_t(0);
 944   } else {
 945     assert(HeapShared::is_heap_object_archiving_allowed(),
 946            "Archiving heap object is not allowed");
 947     _dump_region->append_intptr_t(
 948       (intptr_t)CompressedOops::encode_not_null(*o));
 949   }
 950 }
 951 
 952 void WriteClosure::do_region(u_char* start, size_t size) {
 953   assert((intptr_t)start % sizeof(intptr_t) == 0, "bad alignment");
 954   assert(size % sizeof(intptr_t) == 0, "bad size");
 955   do_tag((int)size);
 956   while (size > 0) {
 957     _dump_region->append_intptr_t(*(intptr_t*)start, true);
 958     start += sizeof(intptr_t);
 959     size -= sizeof(intptr_t);
 960   }
 961 }
 962 
 963 // This is for dumping detailed statistics for the allocations
 964 // in the shared spaces.
 965 class DumpAllocStats : public ResourceObj {
 966 public:
 967 
 968   // Here's poor man's enum inheritance
 969 #define SHAREDSPACE_OBJ_TYPES_DO(f) \
 970   METASPACE_OBJ_TYPES_DO(f) \
 971   f(SymbolHashentry) \
 972   f(SymbolBucket) \
 973   f(StringHashentry) \
 974   f(StringBucket) \
 975   f(Other)
 976 
 977   enum Type {
 978     // Types are MetaspaceObj::ClassType, MetaspaceObj::SymbolType, etc
 979     SHAREDSPACE_OBJ_TYPES_DO(METASPACE_OBJ_TYPE_DECLARE)
 980     _number_of_types
 981   };
 982 
 983   static const char * type_name(Type type) {
 984     switch(type) {
 985     SHAREDSPACE_OBJ_TYPES_DO(METASPACE_OBJ_TYPE_NAME_CASE)
 986     default:
 987       ShouldNotReachHere();
 988       return NULL;
 989     }
 990   }
 991 
 992 public:
 993   enum { RO = 0, RW = 1 };
 994 
 995   int _counts[2][_number_of_types];
 996   int _bytes [2][_number_of_types];
 997 
 998   DumpAllocStats() {
 999     memset(_counts, 0, sizeof(_counts));
1000     memset(_bytes,  0, sizeof(_bytes));
1001   };
1002 
1003   void record(MetaspaceObj::Type type, int byte_size, bool read_only) {
1004     assert(int(type) >= 0 && type < MetaspaceObj::_number_of_types, "sanity");
1005     int which = (read_only) ? RO : RW;
1006     _counts[which][type] ++;
1007     _bytes [which][type] += byte_size;
1008   }
1009 
1010   void record_other_type(int byte_size, bool read_only) {
1011     int which = (read_only) ? RO : RW;
1012     _bytes [which][OtherType] += byte_size;
1013   }
1014   void print_stats(int ro_all, int rw_all, int mc_all, int md_all);
1015 };
1016 
1017 void DumpAllocStats::print_stats(int ro_all, int rw_all, int mc_all, int md_all) {
1018   // Calculate size of data that was not allocated by Metaspace::allocate()
1019   MetaspaceSharedStats *stats = MetaspaceShared::stats();
1020 
1021   // symbols
1022   _counts[RO][SymbolHashentryType] = stats->symbol.hashentry_count;
1023   _bytes [RO][SymbolHashentryType] = stats->symbol.hashentry_bytes;
1024 
1025   _counts[RO][SymbolBucketType] = stats->symbol.bucket_count;
1026   _bytes [RO][SymbolBucketType] = stats->symbol.bucket_bytes;
1027 
1028   // strings
1029   _counts[RO][StringHashentryType] = stats->string.hashentry_count;
1030   _bytes [RO][StringHashentryType] = stats->string.hashentry_bytes;
1031 
1032   _counts[RO][StringBucketType] = stats->string.bucket_count;
1033   _bytes [RO][StringBucketType] = stats->string.bucket_bytes;
1034 
1035   // TODO: count things like dictionary, vtable, etc
1036   _bytes[RW][OtherType] += mc_all + md_all;
1037   rw_all += mc_all + md_all; // mc/md are mapped Read/Write
1038 
1039   // prevent divide-by-zero
1040   if (ro_all < 1) {
1041     ro_all = 1;
1042   }
1043   if (rw_all < 1) {
1044     rw_all = 1;
1045   }
1046 
1047   int all_ro_count = 0;
1048   int all_ro_bytes = 0;
1049   int all_rw_count = 0;
1050   int all_rw_bytes = 0;
1051 
1052 // To make fmt_stats be a syntactic constant (for format warnings), use #define.
1053 #define fmt_stats "%-20s: %8d %10d %5.1f | %8d %10d %5.1f | %8d %10d %5.1f"
1054   const char *sep = "--------------------+---------------------------+---------------------------+--------------------------";
1055   const char *hdr = "                        ro_cnt   ro_bytes     % |   rw_cnt   rw_bytes     % |  all_cnt  all_bytes     %";
1056 
1057   LogMessage(cds) msg;
1058 
1059   msg.info("Detailed metadata info (excluding st regions; rw stats include md/mc regions):");
1060   msg.info("%s", hdr);
1061   msg.info("%s", sep);
1062   for (int type = 0; type < int(_number_of_types); type ++) {
1063     const char *name = type_name((Type)type);
1064     int ro_count = _counts[RO][type];
1065     int ro_bytes = _bytes [RO][type];
1066     int rw_count = _counts[RW][type];
1067     int rw_bytes = _bytes [RW][type];
1068     int count = ro_count + rw_count;
1069     int bytes = ro_bytes + rw_bytes;
1070 
1071     double ro_perc = percent_of(ro_bytes, ro_all);
1072     double rw_perc = percent_of(rw_bytes, rw_all);
1073     double perc    = percent_of(bytes, ro_all + rw_all);
1074 
1075     msg.info(fmt_stats, name,
1076                          ro_count, ro_bytes, ro_perc,
1077                          rw_count, rw_bytes, rw_perc,
1078                          count, bytes, perc);
1079 
1080     all_ro_count += ro_count;
1081     all_ro_bytes += ro_bytes;
1082     all_rw_count += rw_count;
1083     all_rw_bytes += rw_bytes;
1084   }
1085 
1086   int all_count = all_ro_count + all_rw_count;
1087   int all_bytes = all_ro_bytes + all_rw_bytes;
1088 
1089   double all_ro_perc = percent_of(all_ro_bytes, ro_all);
1090   double all_rw_perc = percent_of(all_rw_bytes, rw_all);
1091   double all_perc    = percent_of(all_bytes, ro_all + rw_all);
1092 
1093   msg.info("%s", sep);
1094   msg.info(fmt_stats, "Total",
1095                        all_ro_count, all_ro_bytes, all_ro_perc,
1096                        all_rw_count, all_rw_bytes, all_rw_perc,
1097                        all_count, all_bytes, all_perc);
1098 
1099   assert(all_ro_bytes == ro_all, "everything should have been counted");
1100   assert(all_rw_bytes == rw_all, "everything should have been counted");
1101 
1102 #undef fmt_stats
1103 }
1104 
1105 // Populate the shared space.
1106 
1107 class VM_PopulateDumpSharedSpace: public VM_Operation {
1108 private:
1109   GrowableArray<MemRegion> *_closed_archive_heap_regions;
1110   GrowableArray<MemRegion> *_open_archive_heap_regions;
1111 
1112   GrowableArray<ArchiveHeapOopmapInfo> *_closed_archive_heap_oopmaps;
1113   GrowableArray<ArchiveHeapOopmapInfo> *_open_archive_heap_oopmaps;
1114 
1115   void dump_java_heap_objects() NOT_CDS_JAVA_HEAP_RETURN;
1116   void dump_archive_heap_oopmaps() NOT_CDS_JAVA_HEAP_RETURN;
1117   void dump_archive_heap_oopmaps(GrowableArray<MemRegion>* regions,
1118                                  GrowableArray<ArchiveHeapOopmapInfo>* oopmaps);
1119   void dump_symbols();
1120   char* dump_read_only_tables();
1121   void print_class_stats();
1122   void print_region_stats();
1123   void print_bitmap_region_stats(size_t size, size_t total_size);
1124   void print_heap_region_stats(GrowableArray<MemRegion> *heap_mem,
1125                                const char *name, size_t total_size);
1126   void relocate_to_default_base_address(CHeapBitMap* ptrmap);
1127 
1128 public:
1129 
1130   VMOp_Type type() const { return VMOp_PopulateDumpSharedSpace; }
1131   void doit();   // outline because gdb sucks
1132   static void write_region(FileMapInfo* mapinfo, int region_idx, DumpRegion* dump_region, bool read_only,  bool allow_exec) {
1133     mapinfo->write_region(region_idx, dump_region->base(), dump_region->used(), read_only, allow_exec);
1134   }
1135   bool allow_nested_vm_operations() const { return true; }
1136 }; // class VM_PopulateDumpSharedSpace
1137 
1138 class SortedSymbolClosure: public SymbolClosure {
1139   GrowableArray<Symbol*> _symbols;
1140   virtual void do_symbol(Symbol** sym) {
1141     assert((*sym)->is_permanent(), "archived symbols must be permanent");
1142     _symbols.append(*sym);
1143   }
1144   static int compare_symbols_by_address(Symbol** a, Symbol** b) {
1145     if (a[0] < b[0]) {
1146       return -1;
1147     } else if (a[0] == b[0]) {
1148       return 0;
1149     } else {
1150       return 1;
1151     }
1152   }
1153 
1154 public:
1155   SortedSymbolClosure() {
1156     SymbolTable::symbols_do(this);
1157     _symbols.sort(compare_symbols_by_address);
1158   }
1159   GrowableArray<Symbol*>* get_sorted_symbols() {
1160     return &_symbols;
1161   }
1162 };
1163 
1164 // ArchiveCompactor --
1165 //
1166 // This class is the central piece of shared archive compaction -- all metaspace data are
1167 // initially allocated outside of the shared regions. ArchiveCompactor copies the
1168 // metaspace data into their final location in the shared regions.
1169 
1170 class ArchiveCompactor : AllStatic {
1171   static const int INITIAL_TABLE_SIZE = 8087;
1172   static const int MAX_TABLE_SIZE     = 1000000;
1173 
1174   static DumpAllocStats* _alloc_stats;
1175   static SortedSymbolClosure* _ssc;
1176 
1177   typedef KVHashtable<address, address, mtInternal> RelocationTable;
1178   static RelocationTable* _new_loc_table;
1179 
1180 public:
1181   static void initialize() {
1182     _alloc_stats = new(ResourceObj::C_HEAP, mtInternal)DumpAllocStats;
1183     _new_loc_table = new RelocationTable(INITIAL_TABLE_SIZE);
1184   }
1185   static DumpAllocStats* alloc_stats() {
1186     return _alloc_stats;
1187   }
1188 
1189   // Use this when you allocate space with MetaspaceShare::read_only_space_alloc()
1190   // outside of ArchiveCompactor::allocate(). These are usually for misc tables
1191   // that are allocated in the RO space.
1192   class OtherROAllocMark {
1193     char* _oldtop;
1194   public:
1195     OtherROAllocMark() {
1196       _oldtop = _ro_region.top();
1197     }
1198     ~OtherROAllocMark() {
1199       char* newtop = _ro_region.top();
1200       ArchiveCompactor::alloc_stats()->record_other_type(int(newtop - _oldtop), true);
1201     }
1202   };
1203 
1204   static void allocate(MetaspaceClosure::Ref* ref, bool read_only) {
1205     address obj = ref->obj();
1206     int bytes = ref->size() * BytesPerWord;
1207     char* p;
1208     size_t alignment = BytesPerWord;
1209     char* oldtop;
1210     char* newtop;
1211 
1212     if (read_only) {
1213       oldtop = _ro_region.top();
1214       p = _ro_region.allocate(bytes, alignment);
1215       newtop = _ro_region.top();
1216     } else {
1217       oldtop = _rw_region.top();
1218       if (ref->msotype() == MetaspaceObj::ClassType) {
1219         // Save a pointer immediate in front of an InstanceKlass, so
1220         // we can do a quick lookup from InstanceKlass* -> RunTimeSharedClassInfo*
1221         // without building another hashtable. See RunTimeSharedClassInfo::get_for()
1222         // in systemDictionaryShared.cpp.
1223         Klass* klass = (Klass*)obj;
1224         if (klass->is_instance_klass()) {
1225           SystemDictionaryShared::validate_before_archiving(InstanceKlass::cast(klass));
1226           _rw_region.allocate(sizeof(address), BytesPerWord);
1227         }
1228       }
1229       p = _rw_region.allocate(bytes, alignment);
1230       newtop = _rw_region.top();
1231     }
1232     memcpy(p, obj, bytes);
1233 
1234     assert(_new_loc_table->lookup(obj) == NULL, "each object can be relocated at most once");
1235     _new_loc_table->add(obj, (address)p);
1236     log_trace(cds)("Copy: " PTR_FORMAT " ==> " PTR_FORMAT " %d", p2i(obj), p2i(p), bytes);
1237     if (_new_loc_table->maybe_grow(MAX_TABLE_SIZE)) {
1238       log_info(cds, hashtables)("Expanded _new_loc_table to %d", _new_loc_table->table_size());
1239     }
1240     _alloc_stats->record(ref->msotype(), int(newtop - oldtop), read_only);
1241   }
1242 
1243   static address get_new_loc(MetaspaceClosure::Ref* ref) {
1244     address* pp = _new_loc_table->lookup(ref->obj());
1245     assert(pp != NULL, "must be");
1246     return *pp;
1247   }
1248 
1249 private:
1250   // Makes a shallow copy of visited MetaspaceObj's
1251   class ShallowCopier: public UniqueMetaspaceClosure {
1252     bool _read_only;
1253   public:
1254     ShallowCopier(bool read_only) : _read_only(read_only) {}
1255 
1256     virtual bool do_unique_ref(Ref* ref, bool read_only) {
1257       if (read_only == _read_only) {
1258         allocate(ref, read_only);
1259       }
1260       return true; // recurse into ref.obj()
1261     }
1262   };
1263 
1264   // Relocate embedded pointers within a MetaspaceObj's shallow copy
1265   class ShallowCopyEmbeddedRefRelocator: public UniqueMetaspaceClosure {
1266   public:
1267     virtual bool do_unique_ref(Ref* ref, bool read_only) {
1268       address new_loc = get_new_loc(ref);
1269       RefRelocator refer;
1270       ref->metaspace_pointers_do_at(&refer, new_loc);
1271       return true; // recurse into ref.obj()
1272     }
1273     virtual void push_special(SpecialRef type, Ref* ref, intptr_t* p) {
1274       assert(type == _method_entry_ref, "only special type allowed for now");
1275       address obj = ref->obj();
1276       address new_obj = get_new_loc(ref);
1277       size_t offset = pointer_delta(p, obj,  sizeof(u1));
1278       intptr_t* new_p = (intptr_t*)(new_obj + offset);
1279       assert(*p == *new_p, "must be a copy");
1280       ArchivePtrMarker::mark_pointer((address*)new_p);
1281     }
1282   };
1283 
1284   // Relocate a reference to point to its shallow copy
1285   class RefRelocator: public MetaspaceClosure {
1286   public:
1287     virtual bool do_ref(Ref* ref, bool read_only) {
1288       if (ref->not_null()) {
1289         ref->update(get_new_loc(ref));
1290         ArchivePtrMarker::mark_pointer(ref->addr());
1291       }
1292       return false; // Do not recurse.
1293     }
1294   };
1295 
1296 #ifdef ASSERT
1297   class IsRefInArchiveChecker: public MetaspaceClosure {
1298   public:
1299     virtual bool do_ref(Ref* ref, bool read_only) {
1300       if (ref->not_null()) {
1301         char* obj = (char*)ref->obj();
1302         assert(_ro_region.contains(obj) || _rw_region.contains(obj),
1303                "must be relocated to point to CDS archive");
1304       }
1305       return false; // Do not recurse.
1306     }
1307   };
1308 #endif
1309 
1310 public:
1311   static void copy_and_compact() {
1312     ResourceMark rm;
1313     SortedSymbolClosure the_ssc; // StackObj
1314     _ssc = &the_ssc;
1315 
1316     tty->print_cr("Scanning all metaspace objects ... ");
1317     {
1318       // allocate and shallow-copy RW objects, immediately following the MC region
1319       tty->print_cr("Allocating RW objects ... ");
1320       _mc_region.pack(&_rw_region);
1321 
1322       ResourceMark rm;
1323       ShallowCopier rw_copier(false);
1324       iterate_roots(&rw_copier);
1325     }
1326     {
1327       // allocate and shallow-copy of RO object, immediately following the RW region
1328       tty->print_cr("Allocating RO objects ... ");
1329       _rw_region.pack(&_ro_region);
1330 
1331       ResourceMark rm;
1332       ShallowCopier ro_copier(true);
1333       iterate_roots(&ro_copier);
1334     }
1335     {
1336       tty->print_cr("Relocating embedded pointers ... ");
1337       ResourceMark rm;
1338       ShallowCopyEmbeddedRefRelocator emb_reloc;
1339       iterate_roots(&emb_reloc);
1340     }
1341     {
1342       tty->print_cr("Relocating external roots ... ");
1343       ResourceMark rm;
1344       RefRelocator ext_reloc;
1345       iterate_roots(&ext_reloc);
1346     }
1347 
1348 #ifdef ASSERT
1349     {
1350       tty->print_cr("Verifying external roots ... ");
1351       ResourceMark rm;
1352       IsRefInArchiveChecker checker;
1353       iterate_roots(&checker);
1354     }
1355 #endif
1356 
1357     // cleanup
1358     _ssc = NULL;
1359   }
1360 
1361   // We must relocate the System::_well_known_klasses only after we have copied the
1362   // java objects in during dump_java_heap_objects(): during the object copy, we operate on
1363   // old objects which assert that their klass is the original klass.
1364   static void relocate_well_known_klasses() {
1365     {
1366       tty->print_cr("Relocating SystemDictionary::_well_known_klasses[] ... ");
1367       ResourceMark rm;
1368       RefRelocator ext_reloc;
1369       SystemDictionary::well_known_klasses_do(&ext_reloc);
1370     }
1371     // NOTE: after this point, we shouldn't have any globals that can reach the old
1372     // objects.
1373 
1374     // We cannot use any of the objects in the heap anymore (except for the
1375     // shared strings) because their headers no longer point to valid Klasses.
1376   }
1377 
1378   static void iterate_roots(MetaspaceClosure* it) {
1379     GrowableArray<Symbol*>* symbols = _ssc->get_sorted_symbols();
1380     for (int i=0; i<symbols->length(); i++) {
1381       it->push(symbols->adr_at(i));
1382     }
1383     if (_global_klass_objects != NULL) {
1384       // Need to fix up the pointers
1385       for (int i = 0; i < _global_klass_objects->length(); i++) {
1386         // NOTE -- this requires that the vtable is NOT yet patched, or else we are hosed.
1387         it->push(_global_klass_objects->adr_at(i));
1388       }
1389     }
1390     FileMapInfo::metaspace_pointers_do(it);
1391     SystemDictionaryShared::dumptime_classes_do(it);
1392     Universe::metaspace_pointers_do(it);
1393     SymbolTable::metaspace_pointers_do(it);
1394     vmSymbols::metaspace_pointers_do(it);
1395 
1396     it->finish();
1397   }
1398 
1399   static Klass* get_relocated_klass(Klass* orig_klass) {
1400     assert(DumpSharedSpaces, "dump time only");
1401     address* pp = _new_loc_table->lookup((address)orig_klass);
1402     assert(pp != NULL, "must be");
1403     Klass* klass = (Klass*)(*pp);
1404     assert(klass->is_klass(), "must be");
1405     return klass;
1406   }
1407 };
1408 
1409 DumpAllocStats* ArchiveCompactor::_alloc_stats;
1410 SortedSymbolClosure* ArchiveCompactor::_ssc;
1411 ArchiveCompactor::RelocationTable* ArchiveCompactor::_new_loc_table;
1412 
1413 void VM_PopulateDumpSharedSpace::dump_symbols() {
1414   tty->print_cr("Dumping symbol table ...");
1415 
1416   NOT_PRODUCT(SymbolTable::verify());
1417   SymbolTable::write_to_archive();
1418 }
1419 
1420 char* VM_PopulateDumpSharedSpace::dump_read_only_tables() {
1421   ArchiveCompactor::OtherROAllocMark mark;
1422 
1423   tty->print("Removing java_mirror ... ");
1424   if (!HeapShared::is_heap_object_archiving_allowed()) {
1425     clear_basic_type_mirrors();
1426   }
1427   remove_java_mirror_in_classes();
1428   tty->print_cr("done. ");
1429 
1430   SystemDictionaryShared::write_to_archive();
1431 
1432   size_t vtptrs_bytes = _num_cloned_vtable_kinds * sizeof(intptr_t*);
1433   _cloned_cpp_vtptrs = (intptr_t**)_ro_region.allocate(vtptrs_bytes, sizeof(intptr_t*));
1434 
1435   // Write the other data to the output array.
1436   char* start = _ro_region.top();
1437   WriteClosure wc(&_ro_region);
1438   MetaspaceShared::serialize(&wc);
1439 
1440   // Write the bitmaps for patching the archive heap regions
1441   dump_archive_heap_oopmaps();
1442 
1443   return start;
1444 }
1445 
1446 void VM_PopulateDumpSharedSpace::print_class_stats() {
1447   tty->print_cr("Number of classes %d", _global_klass_objects->length());
1448   {
1449     int num_type_array = 0, num_obj_array = 0, num_inst = 0;
1450     for (int i = 0; i < _global_klass_objects->length(); i++) {
1451       Klass* k = _global_klass_objects->at(i);
1452       if (k->is_instance_klass()) {
1453         num_inst ++;
1454       } else if (k->is_objArray_klass()) {
1455         num_obj_array ++;
1456       } else {
1457         assert(k->is_typeArray_klass(), "sanity");
1458         num_type_array ++;
1459       }
1460     }
1461     tty->print_cr("    instance classes   = %5d", num_inst);
1462     tty->print_cr("    obj array classes  = %5d", num_obj_array);
1463     tty->print_cr("    type array classes = %5d", num_type_array);
1464   }
1465 }
1466 
1467 void VM_PopulateDumpSharedSpace::relocate_to_default_base_address(CHeapBitMap* ptrmap) {
1468   intx addr_delta = MetaspaceShared::final_delta();
1469   if (addr_delta == 0) {
1470     return;
1471   }
1472 
1473   // Patch all pointers that are marked by ptrmap within this region,
1474   // where we have just dumped all the metaspace data.
1475   address patch_base = (address)SharedBaseAddress;
1476   address patch_end  = (address)_md_region.top();
1477   size_t size = patch_end - patch_base;
1478 
1479   // debug only -- the current value of the pointers to be patched must be within this
1480   // range (i.e., must point to valid metaspace objects)
1481   address valid_old_base = patch_base;
1482   address valid_old_end  = patch_end;
1483 
1484   // debug only -- after patching, the pointers must point inside this range
1485   // (the requested location of the archive, as mapped at runtime).
1486   address valid_new_base = (address)Arguments::default_SharedBaseAddress();
1487   address valid_new_end  = valid_new_base + size;
1488 
1489   log_debug(cds)("Relocating archive from [" INTPTR_FORMAT " - " INTPTR_FORMAT " ] to "
1490                  "[" INTPTR_FORMAT " - " INTPTR_FORMAT " ]", p2i(patch_base), p2i(patch_end),
1491                  p2i(valid_new_base), p2i(valid_new_end));
1492 
1493   SharedDataRelocator patcher((address*)patch_base, (address*)patch_end, valid_old_base, valid_old_end,
1494                               valid_new_base, valid_new_end, addr_delta);
1495   ptrmap->iterate(&patcher);
1496 }
1497 
1498 void VM_PopulateDumpSharedSpace::doit() {
1499   CHeapBitMap ptrmap;
1500   MetaspaceShared::initialize_ptr_marker(&ptrmap);
1501 
1502   // We should no longer allocate anything from the metaspace, so that:
1503   //
1504   // (1) Metaspace::allocate might trigger GC if we have run out of
1505   //     committed metaspace, but we can't GC because we're running
1506   //     in the VM thread.
1507   // (2) ArchiveCompactor needs to work with a stable set of MetaspaceObjs.
1508   Metaspace::freeze();
1509   DEBUG_ONLY(SystemDictionaryShared::NoClassLoadingMark nclm);
1510 
1511   Thread* THREAD = VMThread::vm_thread();
1512 
1513   FileMapInfo::check_nonempty_dir_in_shared_path_table();
1514 
1515   NOT_PRODUCT(SystemDictionary::verify();)
1516   // The following guarantee is meant to ensure that no loader constraints
1517   // exist yet, since the constraints table is not shared.  This becomes
1518   // more important now that we don't re-initialize vtables/itables for
1519   // shared classes at runtime, where constraints were previously created.
1520   guarantee(SystemDictionary::constraints()->number_of_entries() == 0,
1521             "loader constraints are not saved");
1522   guarantee(SystemDictionary::placeholders()->number_of_entries() == 0,
1523           "placeholders are not saved");
1524 
1525   // At this point, many classes have been loaded.
1526   // Gather systemDictionary classes in a global array and do everything to
1527   // that so we don't have to walk the SystemDictionary again.
1528   SystemDictionaryShared::check_excluded_classes();
1529   _global_klass_objects = new GrowableArray<Klass*>(1000);
1530   CollectClassesClosure collect_classes;
1531   ClassLoaderDataGraph::loaded_classes_do(&collect_classes);
1532 
1533   print_class_stats();
1534 
1535   // Ensure the ConstMethods won't be modified at run-time
1536   tty->print("Updating ConstMethods ... ");
1537   rewrite_nofast_bytecodes_and_calculate_fingerprints();
1538   tty->print_cr("done. ");
1539 
1540   // Remove all references outside the metadata
1541   tty->print("Removing unshareable information ... ");
1542   remove_unshareable_in_classes();
1543   tty->print_cr("done. ");
1544 
1545   ArchiveCompactor::initialize();
1546   ArchiveCompactor::copy_and_compact();
1547 
1548   dump_symbols();
1549 
1550   // Dump supported java heap objects
1551   _closed_archive_heap_regions = NULL;
1552   _open_archive_heap_regions = NULL;
1553   dump_java_heap_objects();
1554 
1555   ArchiveCompactor::relocate_well_known_klasses();
1556 
1557   char* serialized_data_start = dump_read_only_tables();
1558   _ro_region.pack(&_md_region);
1559 
1560   char* vtbl_list = _md_region.top();
1561   MetaspaceShared::allocate_cpp_vtable_clones();
1562   _md_region.pack();
1563 
1564   // During patching, some virtual methods may be called, so at this point
1565   // the vtables must contain valid methods (as filled in by CppVtableCloner::allocate).
1566   MetaspaceShared::patch_cpp_vtable_pointers();
1567 
1568   // The vtable clones contain addresses of the current process.
1569   // We don't want to write these addresses into the archive.
1570   MetaspaceShared::zero_cpp_vtable_clones_for_writing();
1571 
1572   // relocate the data so that it can be mapped to Arguments::default_SharedBaseAddress
1573   // without runtime relocation.
1574   ArchivePtrMarker::compact((address)SharedBaseAddress, (address)_md_region.top());
1575   relocate_to_default_base_address(&ptrmap);
1576 
1577   // Create and write the archive file that maps the shared spaces.
1578 
1579   FileMapInfo* mapinfo = new FileMapInfo(true);
1580   mapinfo->populate_header(os::vm_allocation_granularity());
1581   mapinfo->set_serialized_data_start(serialized_data_start);
1582   mapinfo->set_misc_data_patching_start(vtbl_list);
1583   mapinfo->set_i2i_entry_code_buffers(MetaspaceShared::i2i_entry_code_buffers(),
1584                                       MetaspaceShared::i2i_entry_code_buffers_size());
1585   mapinfo->open_for_write();
1586 
1587   // NOTE: md contains the trampoline code for method entries, which are patched at run time,
1588   // so it needs to be read/write.
1589   write_region(mapinfo, MetaspaceShared::mc, &_mc_region, /*read_only=*/false,/*allow_exec=*/true);
1590   write_region(mapinfo, MetaspaceShared::rw, &_rw_region, /*read_only=*/false,/*allow_exec=*/false);
1591   write_region(mapinfo, MetaspaceShared::ro, &_ro_region, /*read_only=*/true, /*allow_exec=*/false);
1592   write_region(mapinfo, MetaspaceShared::md, &_md_region, /*read_only=*/false,/*allow_exec=*/false);
1593 
1594   mapinfo->write_bitmap_region(ArchivePtrMarker::ptrmap());
1595 
1596   _total_closed_archive_region_size = mapinfo->write_archive_heap_regions(
1597                                         _closed_archive_heap_regions,
1598                                         _closed_archive_heap_oopmaps,
1599                                         MetaspaceShared::first_closed_archive_heap_region,
1600                                         MetaspaceShared::max_closed_archive_heap_region);
1601   _total_open_archive_region_size = mapinfo->write_archive_heap_regions(
1602                                         _open_archive_heap_regions,
1603                                         _open_archive_heap_oopmaps,
1604                                         MetaspaceShared::first_open_archive_heap_region,
1605                                         MetaspaceShared::max_open_archive_heap_region);
1606 
1607   mapinfo->set_final_requested_base((char*)Arguments::default_SharedBaseAddress());
1608   mapinfo->set_header_crc(mapinfo->compute_header_crc());
1609   mapinfo->write_header();
1610   mapinfo->close();
1611 
1612   // Restore the vtable in case we invoke any virtual methods.
1613   MetaspaceShared::clone_cpp_vtables((intptr_t*)vtbl_list);
1614 
1615   print_region_stats();
1616 
1617   if (log_is_enabled(Info, cds)) {
1618     ArchiveCompactor::alloc_stats()->print_stats(int(_ro_region.used()), int(_rw_region.used()),
1619                                                  int(_mc_region.used()), int(_md_region.used()));
1620   }
1621 
1622   if (PrintSystemDictionaryAtExit) {
1623     SystemDictionary::print();
1624   }
1625 
1626   if (AllowArchivingWithJavaAgent) {
1627     warning("This archive was created with AllowArchivingWithJavaAgent. It should be used "
1628             "for testing purposes only and should not be used in a production environment");
1629   }
1630 
1631   // There may be other pending VM operations that operate on the InstanceKlasses,
1632   // which will fail because InstanceKlasses::remove_unshareable_info()
1633   // has been called. Forget these operations and exit the VM directly.
1634   vm_direct_exit(0);
1635 }
1636 
1637 void VM_PopulateDumpSharedSpace::print_region_stats() {
1638   // Print statistics of all the regions
1639   const size_t bitmap_used = ArchivePtrMarker::ptrmap()->size_in_bytes();
1640   const size_t bitmap_reserved = align_up(bitmap_used, Metaspace::reserve_alignment());
1641   const size_t total_reserved = _ro_region.reserved()  + _rw_region.reserved() +
1642                                 _mc_region.reserved()  + _md_region.reserved() +
1643                                 bitmap_reserved +
1644                                 _total_closed_archive_region_size +
1645                                 _total_open_archive_region_size;
1646   const size_t total_bytes = _ro_region.used()  + _rw_region.used() +
1647                              _mc_region.used()  + _md_region.used() +
1648                              bitmap_used +
1649                              _total_closed_archive_region_size +
1650                              _total_open_archive_region_size;
1651   const double total_u_perc = percent_of(total_bytes, total_reserved);
1652 
1653   _mc_region.print(total_reserved);
1654   _rw_region.print(total_reserved);
1655   _ro_region.print(total_reserved);
1656   _md_region.print(total_reserved);
1657   print_bitmap_region_stats(bitmap_reserved, total_reserved);
1658   print_heap_region_stats(_closed_archive_heap_regions, "ca", total_reserved);
1659   print_heap_region_stats(_open_archive_heap_regions, "oa", total_reserved);
1660 
1661   tty->print_cr("total    : " SIZE_FORMAT_W(9) " [100.0%% of total] out of " SIZE_FORMAT_W(9) " bytes [%5.1f%% used]",
1662                  total_bytes, total_reserved, total_u_perc);
1663 }
1664 
1665 void VM_PopulateDumpSharedSpace::print_bitmap_region_stats(size_t size, size_t total_size) {
1666   tty->print_cr("bm  space: " SIZE_FORMAT_W(9) " [ %4.1f%% of total] out of " SIZE_FORMAT_W(9) " bytes [100.0%% used] at " INTPTR_FORMAT,
1667                 size, size/double(total_size)*100.0, size, p2i(NULL));
1668 }
1669 
1670 void VM_PopulateDumpSharedSpace::print_heap_region_stats(GrowableArray<MemRegion> *heap_mem,
1671                                                          const char *name, size_t total_size) {
1672   int arr_len = heap_mem == NULL ? 0 : heap_mem->length();
1673   for (int i = 0; i < arr_len; i++) {
1674       char* start = (char*)heap_mem->at(i).start();
1675       size_t size = heap_mem->at(i).byte_size();
1676       char* top = start + size;
1677       tty->print_cr("%s%d space: " SIZE_FORMAT_W(9) " [ %4.1f%% of total] out of " SIZE_FORMAT_W(9) " bytes [100.0%% used] at " INTPTR_FORMAT,
1678                     name, i, size, size/double(total_size)*100.0, size, p2i(start));
1679 
1680   }
1681 }
1682 
1683 // Update a Java object to point its Klass* to the new location after
1684 // shared archive has been compacted.
1685 void MetaspaceShared::relocate_klass_ptr(oop o) {
1686   assert(DumpSharedSpaces, "sanity");
1687   Klass* k = ArchiveCompactor::get_relocated_klass(o->klass());
1688   o->set_klass(k);
1689 }
1690 
1691 Klass* MetaspaceShared::get_relocated_klass(Klass *k, bool is_final) {
1692   assert(DumpSharedSpaces, "sanity");
1693   k = ArchiveCompactor::get_relocated_klass(k);
1694   if (is_final) {
1695     k = (Klass*)(address(k) + final_delta());
1696   }
1697   return k;
1698 }
1699 
1700 class LinkSharedClassesClosure : public KlassClosure {
1701   Thread* THREAD;
1702   bool    _made_progress;
1703  public:
1704   LinkSharedClassesClosure(Thread* thread) : THREAD(thread), _made_progress(false) {}
1705 
1706   void reset()               { _made_progress = false; }
1707   bool made_progress() const { return _made_progress; }
1708 
1709   void do_klass(Klass* k) {
1710     if (k->is_instance_klass()) {
1711       InstanceKlass* ik = InstanceKlass::cast(k);
1712       // Link the class to cause the bytecodes to be rewritten and the
1713       // cpcache to be created. Class verification is done according
1714       // to -Xverify setting.
1715       _made_progress |= MetaspaceShared::try_link_class(ik, THREAD);
1716       guarantee(!HAS_PENDING_EXCEPTION, "exception in link_class");
1717 
1718       ik->constants()->resolve_class_constants(THREAD);
1719     }
1720   }
1721 };
1722 
1723 class CheckSharedClassesClosure : public KlassClosure {
1724   bool    _made_progress;
1725  public:
1726   CheckSharedClassesClosure() : _made_progress(false) {}
1727 
1728   void reset()               { _made_progress = false; }
1729   bool made_progress() const { return _made_progress; }
1730   void do_klass(Klass* k) {
1731     if (k->is_instance_klass() && InstanceKlass::cast(k)->check_sharing_error_state()) {
1732       _made_progress = true;
1733     }
1734   }
1735 };
1736 
1737 void MetaspaceShared::link_and_cleanup_shared_classes(TRAPS) {
1738   // We need to iterate because verification may cause additional classes
1739   // to be loaded.
1740   LinkSharedClassesClosure link_closure(THREAD);
1741   do {
1742     link_closure.reset();
1743     ClassLoaderDataGraph::unlocked_loaded_classes_do(&link_closure);
1744     guarantee(!HAS_PENDING_EXCEPTION, "exception in link_class");
1745   } while (link_closure.made_progress());
1746 
1747   if (_has_error_classes) {
1748     // Mark all classes whose super class or interfaces failed verification.
1749     CheckSharedClassesClosure check_closure;
1750     do {
1751       // Not completely sure if we need to do this iteratively. Anyway,
1752       // we should come here only if there are unverifiable classes, which
1753       // shouldn't happen in normal cases. So better safe than sorry.
1754       check_closure.reset();
1755       ClassLoaderDataGraph::unlocked_loaded_classes_do(&check_closure);
1756     } while (check_closure.made_progress());
1757   }
1758 }
1759 
1760 void MetaspaceShared::prepare_for_dumping() {
1761   Arguments::check_unsupported_dumping_properties();
1762   ClassLoader::initialize_shared_path();
1763 }
1764 
1765 // Preload classes from a list, populate the shared spaces and dump to a
1766 // file.
1767 void MetaspaceShared::preload_and_dump(TRAPS) {
1768   { TraceTime timer("Dump Shared Spaces", TRACETIME_LOG(Info, startuptime));
1769     ResourceMark rm;
1770     char class_list_path_str[JVM_MAXPATHLEN];
1771     // Preload classes to be shared.
1772     const char* class_list_path;
1773     if (SharedClassListFile == NULL) {
1774       // Construct the path to the class list (in jre/lib)
1775       // Walk up two directories from the location of the VM and
1776       // optionally tack on "lib" (depending on platform)
1777       os::jvm_path(class_list_path_str, sizeof(class_list_path_str));
1778       for (int i = 0; i < 3; i++) {
1779         char *end = strrchr(class_list_path_str, *os::file_separator());
1780         if (end != NULL) *end = '\0';
1781       }
1782       int class_list_path_len = (int)strlen(class_list_path_str);
1783       if (class_list_path_len >= 3) {
1784         if (strcmp(class_list_path_str + class_list_path_len - 3, "lib") != 0) {
1785           if (class_list_path_len < JVM_MAXPATHLEN - 4) {
1786             jio_snprintf(class_list_path_str + class_list_path_len,
1787                          sizeof(class_list_path_str) - class_list_path_len,
1788                          "%slib", os::file_separator());
1789             class_list_path_len += 4;
1790           }
1791         }
1792       }
1793       if (class_list_path_len < JVM_MAXPATHLEN - 10) {
1794         jio_snprintf(class_list_path_str + class_list_path_len,
1795                      sizeof(class_list_path_str) - class_list_path_len,
1796                      "%sclasslist", os::file_separator());
1797       }
1798       class_list_path = class_list_path_str;
1799     } else {
1800       class_list_path = SharedClassListFile;
1801     }
1802 
1803     tty->print_cr("Loading classes to share ...");
1804     _has_error_classes = false;
1805     int class_count = preload_classes(class_list_path, THREAD);
1806     if (ExtraSharedClassListFile) {
1807       class_count += preload_classes(ExtraSharedClassListFile, THREAD);
1808     }
1809     tty->print_cr("Loading classes to share: done.");
1810 
1811     log_info(cds)("Shared spaces: preloaded %d classes", class_count);
1812 
1813     if (SharedArchiveConfigFile) {
1814       tty->print_cr("Reading extra data from %s ...", SharedArchiveConfigFile);
1815       read_extra_data(SharedArchiveConfigFile, THREAD);
1816     }
1817     tty->print_cr("Reading extra data: done.");
1818 
1819     HeapShared::init_subgraph_entry_fields(THREAD);
1820 
1821     // Rewrite and link classes
1822     tty->print_cr("Rewriting and linking classes ...");
1823 
1824     // Link any classes which got missed. This would happen if we have loaded classes that
1825     // were not explicitly specified in the classlist. E.g., if an interface implemented by class K
1826     // fails verification, all other interfaces that were not specified in the classlist but
1827     // are implemented by K are not verified.
1828     link_and_cleanup_shared_classes(CATCH);
1829     tty->print_cr("Rewriting and linking classes: done");
1830 
1831     if (HeapShared::is_heap_object_archiving_allowed()) {
1832       // Avoid fragmentation while archiving heap objects.
1833       Universe::heap()->soft_ref_policy()->set_should_clear_all_soft_refs(true);
1834       Universe::heap()->collect(GCCause::_archive_time_gc);
1835       Universe::heap()->soft_ref_policy()->set_should_clear_all_soft_refs(false);
1836     }
1837 
1838     VM_PopulateDumpSharedSpace op;
1839     VMThread::execute(&op);
1840   }
1841 }
1842 
1843 
1844 int MetaspaceShared::preload_classes(const char* class_list_path, TRAPS) {
1845   ClassListParser parser(class_list_path);
1846   int class_count = 0;
1847 
1848   while (parser.parse_one_line()) {
1849     Klass* klass = parser.load_current_class(THREAD);
1850     if (HAS_PENDING_EXCEPTION) {
1851       if (klass == NULL &&
1852           (PENDING_EXCEPTION->klass()->name() == vmSymbols::java_lang_ClassNotFoundException())) {
1853         // print a warning only when the pending exception is class not found
1854         log_warning(cds)("Preload Warning: Cannot find %s", parser.current_class_name());
1855       }
1856       CLEAR_PENDING_EXCEPTION;
1857     }
1858     if (klass != NULL) {
1859       if (log_is_enabled(Trace, cds)) {
1860         ResourceMark rm;
1861         log_trace(cds)("Shared spaces preloaded: %s", klass->external_name());
1862       }
1863 
1864       if (klass->is_instance_klass()) {
1865         InstanceKlass* ik = InstanceKlass::cast(klass);
1866 
1867         // Link the class to cause the bytecodes to be rewritten and the
1868         // cpcache to be created. The linking is done as soon as classes
1869         // are loaded in order that the related data structures (klass and
1870         // cpCache) are located together.
1871         try_link_class(ik, THREAD);
1872         guarantee(!HAS_PENDING_EXCEPTION, "exception in link_class");
1873       }
1874 
1875       class_count++;
1876     }
1877   }
1878 
1879   return class_count;
1880 }
1881 
1882 // Returns true if the class's status has changed
1883 bool MetaspaceShared::try_link_class(InstanceKlass* ik, TRAPS) {
1884   assert(DumpSharedSpaces, "should only be called during dumping");
1885   if (ik->init_state() < InstanceKlass::linked) {
1886     bool saved = BytecodeVerificationLocal;
1887     if (ik->loader_type() == 0 && ik->class_loader() == NULL) {
1888       // The verification decision is based on BytecodeVerificationRemote
1889       // for non-system classes. Since we are using the NULL classloader
1890       // to load non-system classes for customized class loaders during dumping,
1891       // we need to temporarily change BytecodeVerificationLocal to be the same as
1892       // BytecodeVerificationRemote. Note this can cause the parent system
1893       // classes also being verified. The extra overhead is acceptable during
1894       // dumping.
1895       BytecodeVerificationLocal = BytecodeVerificationRemote;
1896     }
1897     ik->link_class(THREAD);
1898     if (HAS_PENDING_EXCEPTION) {
1899       ResourceMark rm;
1900       log_warning(cds)("Preload Warning: Verification failed for %s",
1901                     ik->external_name());
1902       CLEAR_PENDING_EXCEPTION;
1903       ik->set_in_error_state();
1904       _has_error_classes = true;
1905     }
1906     BytecodeVerificationLocal = saved;
1907     return true;
1908   } else {
1909     return false;
1910   }
1911 }
1912 
1913 #if INCLUDE_CDS_JAVA_HEAP
1914 void VM_PopulateDumpSharedSpace::dump_java_heap_objects() {
1915   // The closed and open archive heap space has maximum two regions.
1916   // See FileMapInfo::write_archive_heap_regions() for details.
1917   _closed_archive_heap_regions = new GrowableArray<MemRegion>(2);
1918   _open_archive_heap_regions = new GrowableArray<MemRegion>(2);
1919   HeapShared::archive_java_heap_objects(_closed_archive_heap_regions,
1920                                         _open_archive_heap_regions);
1921   ArchiveCompactor::OtherROAllocMark mark;
1922   HeapShared::write_subgraph_info_table();
1923 }
1924 
1925 void VM_PopulateDumpSharedSpace::dump_archive_heap_oopmaps() {
1926   if (HeapShared::is_heap_object_archiving_allowed()) {
1927     _closed_archive_heap_oopmaps = new GrowableArray<ArchiveHeapOopmapInfo>(2);
1928     dump_archive_heap_oopmaps(_closed_archive_heap_regions, _closed_archive_heap_oopmaps);
1929 
1930     _open_archive_heap_oopmaps = new GrowableArray<ArchiveHeapOopmapInfo>(2);
1931     dump_archive_heap_oopmaps(_open_archive_heap_regions, _open_archive_heap_oopmaps);
1932   }
1933 }
1934 
1935 void VM_PopulateDumpSharedSpace::dump_archive_heap_oopmaps(GrowableArray<MemRegion>* regions,
1936                                                            GrowableArray<ArchiveHeapOopmapInfo>* oopmaps) {
1937   for (int i=0; i<regions->length(); i++) {
1938     ResourceBitMap oopmap = HeapShared::calculate_oopmap(regions->at(i));
1939     size_t size_in_bits = oopmap.size();
1940     size_t size_in_bytes = oopmap.size_in_bytes();
1941     uintptr_t* buffer = (uintptr_t*)_ro_region.allocate(size_in_bytes, sizeof(intptr_t));
1942     oopmap.write_to(buffer, size_in_bytes);
1943     log_info(cds)("Oopmap = " INTPTR_FORMAT " (" SIZE_FORMAT_W(6) " bytes) for heap region "
1944                   INTPTR_FORMAT " (" SIZE_FORMAT_W(8) " bytes)",
1945                   p2i(buffer), size_in_bytes,
1946                   p2i(regions->at(i).start()), regions->at(i).byte_size());
1947 
1948     ArchiveHeapOopmapInfo info;
1949     info._oopmap = (address)buffer;
1950     info._oopmap_size_in_bits = size_in_bits;
1951     oopmaps->append(info);
1952   }
1953 }
1954 #endif // INCLUDE_CDS_JAVA_HEAP
1955 
1956 void ReadClosure::do_ptr(void** p) {
1957   assert(*p == NULL, "initializing previous initialized pointer.");
1958   intptr_t obj = nextPtr();
1959   assert((intptr_t)obj >= 0 || (intptr_t)obj < -100,
1960          "hit tag while initializing ptrs.");
1961   *p = (void*)obj;
1962 }
1963 
1964 void ReadClosure::do_u4(u4* p) {
1965   intptr_t obj = nextPtr();
1966   *p = (u4)(uintx(obj));
1967 }
1968 
1969 void ReadClosure::do_bool(bool* p) {
1970   intptr_t obj = nextPtr();
1971   *p = (bool)(uintx(obj));
1972 }
1973 
1974 void ReadClosure::do_tag(int tag) {
1975   int old_tag;
1976   old_tag = (int)(intptr_t)nextPtr();
1977   // do_int(&old_tag);
1978   assert(tag == old_tag, "old tag doesn't match");
1979   FileMapInfo::assert_mark(tag == old_tag);
1980 }
1981 
1982 void ReadClosure::do_oop(oop *p) {
1983   narrowOop o = (narrowOop)nextPtr();
1984   if (o == 0 || !HeapShared::open_archive_heap_region_mapped()) {
1985     p = NULL;
1986   } else {
1987     assert(HeapShared::is_heap_object_archiving_allowed(),
1988            "Archived heap object is not allowed");
1989     assert(HeapShared::open_archive_heap_region_mapped(),
1990            "Open archive heap region is not mapped");
1991     *p = HeapShared::decode_from_archive(o);
1992   }
1993 }
1994 
1995 void ReadClosure::do_mirror_oop(oop *p) {
1996   do_oop(p);
1997   oop mirror = *p;
1998   if (mirror != NULL) {
1999     java_lang_Class::update_archived_mirror_native_pointers(mirror);
2000   }
2001 }
2002 
2003 void ReadClosure::do_region(u_char* start, size_t size) {
2004   assert((intptr_t)start % sizeof(intptr_t) == 0, "bad alignment");
2005   assert(size % sizeof(intptr_t) == 0, "bad size");
2006   do_tag((int)size);
2007   while (size > 0) {
2008     *(intptr_t*)start = nextPtr();
2009     start += sizeof(intptr_t);
2010     size -= sizeof(intptr_t);
2011   }
2012 }
2013 
2014 void MetaspaceShared::set_shared_metaspace_range(void* base, void *static_top, void* top) {
2015   assert(base <= static_top && static_top <= top, "must be");
2016   _shared_metaspace_static_top = static_top;
2017   MetaspaceObj::set_shared_metaspace_range(base, top);
2018 }
2019 
2020 // Return true if given address is in the misc data region
2021 bool MetaspaceShared::is_in_shared_region(const void* p, int idx) {
2022   return UseSharedSpaces && FileMapInfo::current_info()->is_in_shared_region(p, idx);
2023 }
2024 
2025 bool MetaspaceShared::is_in_trampoline_frame(address addr) {
2026   if (UseSharedSpaces && is_in_shared_region(addr, MetaspaceShared::mc)) {
2027     return true;
2028   }
2029   return false;
2030 }
2031 
2032 bool MetaspaceShared::is_shared_dynamic(void* p) {
2033   if ((p < MetaspaceObj::shared_metaspace_top()) &&
2034       (p >= _shared_metaspace_static_top)) {
2035     return true;
2036   } else {
2037     return false;
2038   }
2039 }
2040 
2041 void MetaspaceShared::initialize_runtime_shared_and_meta_spaces() {
2042   assert(UseSharedSpaces, "Must be called when UseSharedSpaces is enabled");
2043   MapArchiveResult result = MAP_ARCHIVE_OTHER_FAILURE;
2044   FileMapInfo* static_mapinfo = open_static_archive();
2045   FileMapInfo* dynamic_mapinfo = NULL;
2046 
2047   if (static_mapinfo != NULL) {
2048     dynamic_mapinfo = open_dynamic_archive();
2049 
2050     // First try to map at the requested address
2051     result = map_archives(static_mapinfo, dynamic_mapinfo, true);
2052     if (result == MAP_ARCHIVE_MMAP_FAILURE) {
2053       // Mapping has failed (probably due to ASLR). Let's map at an address chosen
2054       // by the OS.
2055       result = map_archives(static_mapinfo, dynamic_mapinfo, false);
2056     }
2057   }
2058 
2059   if (result == MAP_ARCHIVE_SUCCESS) {
2060     bool dynamic_mapped = (dynamic_mapinfo != NULL && dynamic_mapinfo->is_mapped());
2061     char* cds_base = static_mapinfo->mapped_base();
2062     char* cds_end =  dynamic_mapped ? dynamic_mapinfo->mapped_end() : static_mapinfo->mapped_end();
2063     set_shared_metaspace_range(cds_base, static_mapinfo->mapped_end(), cds_end);
2064     _mapping_delta = static_mapinfo->mapping_delta();
2065     if (dynamic_mapped) {
2066       FileMapInfo::set_shared_path_table(dynamic_mapinfo);
2067     } else {
2068       FileMapInfo::set_shared_path_table(static_mapinfo);
2069     }
2070   } else {
2071     set_shared_metaspace_range(NULL, NULL, NULL);
2072     UseSharedSpaces = false;
2073     FileMapInfo::fail_continue("Unable to map shared spaces");
2074     if (PrintSharedArchiveAndExit) {
2075       vm_exit_during_initialization("Unable to use shared archive.");
2076     }
2077   }
2078 
2079   if (static_mapinfo != NULL && !static_mapinfo->is_mapped()) {
2080     delete static_mapinfo;
2081   }
2082   if (dynamic_mapinfo != NULL && !dynamic_mapinfo->is_mapped()) {
2083     delete dynamic_mapinfo;
2084   }
2085 }
2086 
2087 FileMapInfo* MetaspaceShared::open_static_archive() {
2088   FileMapInfo* mapinfo = new FileMapInfo(true);
2089   if (!mapinfo->initialize()) {
2090     delete(mapinfo);
2091     return NULL;
2092   }
2093   return mapinfo;
2094 }
2095 
2096 FileMapInfo* MetaspaceShared::open_dynamic_archive() {
2097   if (DynamicDumpSharedSpaces) {
2098     return NULL;
2099   }
2100   if (Arguments::GetSharedDynamicArchivePath() == NULL) {
2101     return NULL;
2102   }
2103 
2104   FileMapInfo* mapinfo = new FileMapInfo(false);
2105   if (!mapinfo->initialize()) {
2106     delete(mapinfo);
2107     return NULL;
2108   }
2109   return mapinfo;
2110 }
2111 
2112 MapArchiveResult MetaspaceShared::map_archives(FileMapInfo* static_mapinfo, FileMapInfo* dynamic_mapinfo,
2113                                                bool use_requested_addr) {
2114   // Uncomment the next line to benchmark mapping at alternative locations.
2115   // if (SharedBaseAddress == 0 && use_requested_addr) { return MAP_ARCHIVE_MMAP_FAILURE; }
2116 
2117   if (dynamic_mapinfo != NULL) {
2118     // Ensure that the OS won't be able to allocate new memory spaces between the two
2119     // archives, or else it would mess up the simple comparision in MetaspaceObj::is_shared().
2120     assert(static_mapinfo->mapping_end_offset() == dynamic_mapinfo->mapping_base_offset(), "no gap");
2121   }
2122 
2123   ReservedSpace main_rs, archive_space_rs, class_space_rs;
2124   MapArchiveResult result = MAP_ARCHIVE_OTHER_FAILURE;
2125   char* mapped_base_address = reserve_address_space_for_archives(static_mapinfo, dynamic_mapinfo,
2126                                                                  use_requested_addr, main_rs, archive_space_rs,
2127                                                                  class_space_rs);
2128   if (mapped_base_address == NULL) {
2129     result = MAP_ARCHIVE_MMAP_FAILURE;
2130   } else {
2131     log_debug(cds)("Reserved archive_space_rs     [" INTPTR_FORMAT " - " INTPTR_FORMAT "] (" SIZE_FORMAT ") bytes",
2132                    p2i(archive_space_rs.base()), p2i(archive_space_rs.end()), archive_space_rs.size());
2133     log_debug(cds)("Reserved class_space_rs [" INTPTR_FORMAT " - " INTPTR_FORMAT "] (" SIZE_FORMAT ") bytes",
2134                    p2i(class_space_rs.base()), p2i(class_space_rs.end()), class_space_rs.size());
2135     MapArchiveResult static_result = map_archive(static_mapinfo, mapped_base_address, archive_space_rs);
2136     MapArchiveResult dynamic_result = (static_result == MAP_ARCHIVE_SUCCESS) ?
2137                                      map_archive(dynamic_mapinfo, mapped_base_address, archive_space_rs) : MAP_ARCHIVE_OTHER_FAILURE;
2138 
2139     if (static_result == MAP_ARCHIVE_SUCCESS) {
2140       if (dynamic_result == MAP_ARCHIVE_SUCCESS) {
2141         result = MAP_ARCHIVE_SUCCESS;
2142       } else if (dynamic_result == MAP_ARCHIVE_OTHER_FAILURE) {
2143         assert(dynamic_mapinfo != NULL && !dynamic_mapinfo->is_mapped(), "must have failed");
2144         // No need to retry mapping the dynamic archive again, as it will never succeed
2145         // (bad file, etc) -- just keep the base archive.
2146         log_warning(cds, dynamic)("Unable to use shared archive. The top archive failed to load: %s",
2147                                   dynamic_mapinfo->full_path());
2148         result = MAP_ARCHIVE_SUCCESS;
2149         // FIXME: reduce archive space end ....
2150       } else {
2151         result = MAP_ARCHIVE_MMAP_FAILURE;
2152       }
2153     } else if (static_result == MAP_ARCHIVE_OTHER_FAILURE) {
2154       result = MAP_ARCHIVE_OTHER_FAILURE;
2155     } else {
2156       result = MAP_ARCHIVE_MMAP_FAILURE;
2157     }
2158   }
2159 
2160   if (result == MAP_ARCHIVE_SUCCESS) {
2161     if (!main_rs.is_reserved() && class_space_rs.is_reserved()) {
2162       MemTracker::record_virtual_memory_type((address)class_space_rs.base(), mtClass);
2163     }
2164     SharedBaseAddress = (size_t)mapped_base_address;
2165     LP64_ONLY({
2166         if (Metaspace::using_class_space()) {
2167           assert(class_space_rs.is_reserved(), "must be");
2168           char* cds_base = static_mapinfo->mapped_base();
2169           Metaspace::allocate_metaspace_compressed_klass_ptrs(class_space_rs, NULL, (address)cds_base);
2170           // map_heap_regions() compares the current narrow oop and klass encodings
2171           // with the archived ones, so it must be done after all encodings are determined.
2172           static_mapinfo->map_heap_regions();
2173         }
2174         CompressedKlassPointers::set_range(CompressedClassSpaceSize);
2175       });
2176   } else {
2177     unmap_archive(static_mapinfo);
2178     unmap_archive(dynamic_mapinfo);
2179     release_reserved_spaces(main_rs, archive_space_rs, class_space_rs);
2180   }
2181 
2182   return result;
2183 }
2184 
2185 char* MetaspaceShared::reserve_address_space_for_archives(FileMapInfo* static_mapinfo,
2186                                                           FileMapInfo* dynamic_mapinfo,
2187                                                           bool use_requested_addr,
2188                                                           ReservedSpace& main_rs,
2189                                                           ReservedSpace& archive_space_rs,
2190                                                           ReservedSpace& class_space_rs) {
2191   const bool use_klass_space = NOT_LP64(false) LP64_ONLY(Metaspace::using_class_space());
2192   const size_t class_space_size = NOT_LP64(0) LP64_ONLY(Metaspace::compressed_class_space_size());
2193 
2194   if (use_klass_space) {
2195     assert(class_space_size > 0, "CompressedClassSpaceSize must have been validated");
2196   }
2197   if (use_requested_addr && !is_aligned(static_mapinfo->requested_base_address(), reserved_space_alignment())) {
2198     return NULL;
2199   }
2200 
2201   // Size and requested location of the archive_space_rs (for both static and dynamic archives)
2202   size_t base_offset = static_mapinfo->mapping_base_offset();
2203   size_t end_offset  = (dynamic_mapinfo == NULL) ? static_mapinfo->mapping_end_offset() : dynamic_mapinfo->mapping_end_offset();
2204   assert(base_offset == 0, "must be");
2205   assert(is_aligned(end_offset,  os::vm_allocation_granularity()), "must be");
2206   assert(is_aligned(base_offset, os::vm_allocation_granularity()), "must be");
2207 
2208   // In case reserved_space_alignment() != os::vm_allocation_granularity()
2209   assert((size_t)os::vm_allocation_granularity() <= reserved_space_alignment(), "must be");
2210   end_offset = align_up(end_offset, reserved_space_alignment()); 
2211 
2212   size_t archive_space_size = end_offset - base_offset;
2213 
2214   // Special handling for Windows because it cannot mmap into a reserved space:
2215   //    use_requested_addr: We just map each region individually, and give up if any one of them fails.
2216   //   !use_requested_addr: We reserve the space first, and then os::read in all the regions (instead of mmap).
2217   //                        We're going to patch all the pointers anyway so there's no benefit for mmap.
2218 
2219   if (use_requested_addr) {
2220     char* archive_space_base = static_mapinfo->requested_base_address() + base_offset;
2221     char* archive_space_end  = archive_space_base + archive_space_size;
2222     if (!MetaspaceShared::use_windows_memory_mapping()) {
2223       archive_space_rs = reserve_shared_space(archive_space_size, archive_space_base);
2224       if (!archive_space_rs.is_reserved()) {
2225         return NULL;
2226       }
2227     }
2228     if (use_klass_space) {
2229       // Make sure we can map the klass space immediately following the archive_space space
2230       char* class_space_base = archive_space_end;
2231       class_space_rs = reserve_shared_space(class_space_size, class_space_base);
2232       if (!class_space_rs.is_reserved()) {
2233         return NULL;
2234       }
2235     }
2236     return static_mapinfo->requested_base_address();
2237   } else {
2238     if (use_klass_space) {
2239       main_rs = reserve_shared_space(archive_space_size + class_space_size);
2240       if (main_rs.is_reserved()) {
2241         archive_space_rs = main_rs.first_part(archive_space_size, reserved_space_alignment(), /*split=*/true);
2242         class_space_rs = main_rs.last_part(archive_space_size);
2243       }
2244     } else {
2245       main_rs = reserve_shared_space(archive_space_size);
2246       archive_space_rs = main_rs;
2247     }
2248     if (archive_space_rs.is_reserved()) {
2249       return archive_space_rs.base();
2250     } else {
2251       return NULL;
2252     }
2253   }
2254 }
2255 
2256 void MetaspaceShared::release_reserved_spaces(ReservedSpace& main_rs,
2257                                               ReservedSpace& archive_space_rs,
2258                                               ReservedSpace& class_space_rs) {
2259   if (main_rs.is_reserved()) {
2260     assert(main_rs.contains(archive_space_rs.base()), "must be");
2261     assert(main_rs.contains(class_space_rs.base()), "must be");
2262     log_debug(cds)("Released shared space (archive+classes) " INTPTR_FORMAT, p2i(main_rs.base()));
2263     main_rs.release();
2264   } else {
2265     if (archive_space_rs.is_reserved()) {
2266       log_debug(cds)("Released shared space (archive) " INTPTR_FORMAT, p2i(archive_space_rs.base()));
2267       archive_space_rs.release();
2268     }
2269     if (class_space_rs.is_reserved()) {
2270       log_debug(cds)("Released shared space (classes) " INTPTR_FORMAT, p2i(class_space_rs.base()));
2271       class_space_rs.release();
2272     }
2273   }
2274 }
2275 
2276 static int static_regions[]  = {MetaspaceShared::mc,
2277                                 MetaspaceShared::rw,
2278                                 MetaspaceShared::ro,
2279                                 MetaspaceShared::md};
2280 static int dynamic_regions[] = {MetaspaceShared::rw,
2281                                 MetaspaceShared::ro,
2282                                 MetaspaceShared::mc};
2283 static int static_regions_count  = 4;
2284 static int dynamic_regions_count = 3;
2285 
2286 MapArchiveResult MetaspaceShared::map_archive(FileMapInfo* mapinfo, char* mapped_base_address, ReservedSpace rs) {
2287   assert(UseSharedSpaces, "must be runtime");
2288   if (mapinfo == NULL) {
2289     return MAP_ARCHIVE_SUCCESS; // no error has happeed -- trivially succeeded.
2290   }
2291 
2292   mapinfo->set_is_mapped(false);
2293 
2294   if (mapinfo->alignment() != (size_t)os::vm_allocation_granularity()) { // FIXME
2295     // FIXME log
2296     return MAP_ARCHIVE_OTHER_FAILURE;
2297   }
2298 
2299   MapArchiveResult result = mapinfo->is_static() ?
2300     mapinfo->map_regions(static_regions, static_regions_count, mapped_base_address, rs) :
2301     mapinfo->map_regions(dynamic_regions, dynamic_regions_count, mapped_base_address, rs);
2302 
2303   if (result != MAP_ARCHIVE_SUCCESS) {
2304     unmap_archive(mapinfo);
2305     return result;
2306   }
2307 
2308   if (mapinfo->is_static()) {
2309     if (!mapinfo->validate_shared_path_table()) {
2310       unmap_archive(mapinfo);
2311       return MAP_ARCHIVE_OTHER_FAILURE;
2312     }
2313   } else {
2314     if (!DynamicArchive::validate(mapinfo)) {
2315       unmap_archive(mapinfo);
2316       return MAP_ARCHIVE_OTHER_FAILURE;
2317     }
2318   }
2319 
2320   mapinfo->set_is_mapped(true);
2321   return MAP_ARCHIVE_SUCCESS;
2322 }
2323 
2324 void MetaspaceShared::unmap_archive(FileMapInfo* mapinfo) {
2325   assert(UseSharedSpaces, "must be runtime");
2326   if (mapinfo != NULL) {
2327     if (mapinfo->is_static()) {
2328       mapinfo->unmap_regions(static_regions, static_regions_count);
2329     } else {
2330       mapinfo->unmap_regions(dynamic_regions, dynamic_regions_count);
2331     }
2332     mapinfo->set_is_mapped(false);
2333   }
2334 }
2335 
2336 // Read the miscellaneous data from the shared file, and
2337 // serialize it out to its various destinations.
2338 
2339 void MetaspaceShared::initialize_shared_spaces() {
2340   FileMapInfo *static_mapinfo = FileMapInfo::current_info();
2341   _i2i_entry_code_buffers = static_mapinfo->i2i_entry_code_buffers();
2342   _i2i_entry_code_buffers_size = static_mapinfo->i2i_entry_code_buffers_size();
2343   char* buffer = static_mapinfo->misc_data_patching_start();
2344   clone_cpp_vtables((intptr_t*)buffer);
2345 
2346   // Verify various attributes of the archive, plus initialize the
2347   // shared string/symbol tables
2348   buffer = static_mapinfo->serialized_data_start();
2349   intptr_t* array = (intptr_t*)buffer;
2350   ReadClosure rc(&array);
2351   serialize(&rc);
2352 
2353   // Initialize the run-time symbol table.
2354   SymbolTable::create_table();
2355 
2356   static_mapinfo->patch_archived_heap_embedded_pointers();
2357 
2358   // Close the mapinfo file
2359   static_mapinfo->close();
2360 
2361   FileMapInfo *dynamic_mapinfo = FileMapInfo::dynamic_info();
2362   if (dynamic_mapinfo != NULL) {
2363     intptr_t* buffer = (intptr_t*)dynamic_mapinfo->serialized_data_start();
2364     ReadClosure rc(&buffer);
2365     SymbolTable::serialize_shared_table_header(&rc, false);
2366     SystemDictionaryShared::serialize_dictionary_headers(&rc, false);
2367     dynamic_mapinfo->close();
2368   }
2369 
2370   if (PrintSharedArchiveAndExit) {
2371     if (PrintSharedDictionary) {
2372       tty->print_cr("\nShared classes:\n");
2373       SystemDictionaryShared::print_on(tty);
2374     }
2375     if (FileMapInfo::current_info() == NULL || _archive_loading_failed) {
2376       tty->print_cr("archive is invalid");
2377       vm_exit(1);
2378     } else {
2379       tty->print_cr("archive is valid");
2380       vm_exit(0);
2381     }
2382   }
2383 }
2384 
2385 // JVM/TI RedefineClasses() support:
2386 bool MetaspaceShared::remap_shared_readonly_as_readwrite() {
2387   assert(SafepointSynchronize::is_at_safepoint(), "must be at safepoint");
2388 
2389   if (UseSharedSpaces) {
2390     // remap the shared readonly space to shared readwrite, private
2391     FileMapInfo* mapinfo = FileMapInfo::current_info();
2392     if (!mapinfo->remap_shared_readonly_as_readwrite()) {
2393       return false;
2394     }
2395     if (FileMapInfo::dynamic_info() != NULL) {
2396       mapinfo = FileMapInfo::dynamic_info();
2397       if (!mapinfo->remap_shared_readonly_as_readwrite()) {
2398         return false;
2399       }
2400     }
2401     _remapped_readwrite = true;
2402   }
2403   return true;
2404 }
2405 
2406 void MetaspaceShared::report_out_of_space(const char* name, size_t needed_bytes) {
2407   // This is highly unlikely to happen on 64-bits because we have reserved a 4GB space.
2408   // On 32-bit we reserve only 256MB so you could run out of space with 100,000 classes
2409   // or so.
2410   _mc_region.print_out_of_space_msg(name, needed_bytes);
2411   _rw_region.print_out_of_space_msg(name, needed_bytes);
2412   _ro_region.print_out_of_space_msg(name, needed_bytes);
2413   _md_region.print_out_of_space_msg(name, needed_bytes);
2414 
2415   vm_exit_during_initialization(err_msg("Unable to allocate from '%s' region", name),
2416                                 "Please reduce the number of shared classes.");
2417 }
2418 
2419 intx MetaspaceShared::final_delta() { // FIXME rename
2420   return intx(Arguments::default_SharedBaseAddress())  // We want the archive to be mapped to here at runtime
2421        - intx(SharedBaseAddress);   // .. but the archive is mapped at here at dump time
2422 }