1 /*
2 * Copyright (c) 2012, 2018, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 #include "precompiled.hpp"
26 #include "jvm.h"
27 #include "classfile/classListParser.hpp"
28 #include "classfile/classLoaderExt.hpp"
29 #include "classfile/dictionary.hpp"
30 #include "classfile/loaderConstraints.hpp"
31 #include "classfile/placeholders.hpp"
32 #include "classfile/symbolTable.hpp"
33 #include "classfile/stringTable.hpp"
34 #include "classfile/systemDictionary.hpp"
35 #include "classfile/systemDictionaryShared.hpp"
36 #include "code/codeCache.hpp"
37 #include "interpreter/bytecodeStream.hpp"
38 #include "interpreter/bytecodes.hpp"
39 #include "logging/log.hpp"
40 #include "logging/logMessage.hpp"
41 #include "memory/filemap.hpp"
42 #include "memory/metaspace.hpp"
43 #include "memory/metaspaceClosure.hpp"
44 #include "memory/metaspaceShared.hpp"
45 #include "memory/resourceArea.hpp"
46 #include "oops/compressedOops.inline.hpp"
47 #include "oops/instanceClassLoaderKlass.hpp"
48 #include "oops/instanceMirrorKlass.hpp"
49 #include "oops/instanceRefKlass.hpp"
50 #include "oops/objArrayKlass.hpp"
51 #include "oops/objArrayOop.hpp"
52 #include "oops/oop.inline.hpp"
53 #include "oops/typeArrayKlass.hpp"
54 #include "prims/jvmtiRedefineClasses.hpp"
55 #include "runtime/handles.inline.hpp"
56 #include "runtime/os.hpp"
57 #include "runtime/safepointVerifiers.hpp"
58 #include "runtime/signature.hpp"
59 #include "runtime/timerTrace.hpp"
60 #include "runtime/vmThread.hpp"
61 #include "runtime/vm_operations.hpp"
62 #include "utilities/align.hpp"
63 #include "utilities/defaultStream.hpp"
64 #include "utilities/hashtable.inline.hpp"
65 #if INCLUDE_G1GC
66 #include "gc/g1/g1Allocator.inline.hpp"
67 #include "gc/g1/g1CollectedHeap.hpp"
68 #endif
69
70 ReservedSpace MetaspaceShared::_shared_rs;
71 VirtualSpace MetaspaceShared::_shared_vs;
72 MetaspaceSharedStats MetaspaceShared::_stats;
73 bool MetaspaceShared::_has_error_classes;
74 bool MetaspaceShared::_archive_loading_failed = false;
75 bool MetaspaceShared::_remapped_readwrite = false;
76 bool MetaspaceShared::_open_archive_heap_region_mapped = false;
77 address MetaspaceShared::_cds_i2i_entry_code_buffers = NULL;
78 size_t MetaspaceShared::_cds_i2i_entry_code_buffers_size = 0;
79 size_t MetaspaceShared::_core_spaces_size = 0;
80
81 // The CDS archive is divided into the following regions:
82 // mc - misc code (the method entry trampolines)
83 // rw - read-write metadata
84 // ro - read-only metadata and read-only tables
85 // md - misc data (the c++ vtables)
86 // od - optional data (original class files)
87 //
88 // s0 - shared strings(closed archive heap space) #0
89 // s1 - shared strings(closed archive heap space) #1 (may be empty)
90 // oa0 - open archive heap space #0
91 // oa1 - open archive heap space #1 (may be empty)
92 //
93 // The mc, rw, ro, md and od regions are linearly allocated, starting from
94 // SharedBaseAddress, in the order of mc->rw->ro->md->od. The size of these 5 regions
95 // are page-aligned, and there's no gap between any consecutive regions.
96 //
97 // These 5 regions are populated in the following steps:
98 // [1] All classes are loaded in MetaspaceShared::preload_classes(). All metadata are
99 // temporarily allocated outside of the shared regions. Only the method entry
100 // trampolines are written into the mc region.
101 // [2] ArchiveCompactor copies RW metadata into the rw region.
102 // [3] ArchiveCompactor copies RO metadata into the ro region.
103 // [4] SymbolTable, StringTable, SystemDictionary, and a few other read-only data
104 // are copied into the ro region as read-only tables.
105 // [5] C++ vtables are copied into the md region.
106 // [6] Original class files are copied into the od region.
107 //
108 // The s0/s1 and oa0/oa1 regions are populated inside MetaspaceShared::dump_java_heap_objects.
109 // Their layout is independent of the other 5 regions.
110
111 class DumpRegion {
112 private:
113 const char* _name;
114 char* _base;
115 char* _top;
116 char* _end;
117 bool _is_packed;
118
119 char* expand_top_to(char* newtop) {
120 assert(is_allocatable(), "must be initialized and not packed");
121 assert(newtop >= _top, "must not grow backwards");
122 if (newtop > _end) {
123 MetaspaceShared::report_out_of_space(_name, newtop - _top);
124 ShouldNotReachHere();
125 }
126 MetaspaceShared::commit_shared_space_to(newtop);
127 _top = newtop;
128 return _top;
129 }
130
131 public:
132 DumpRegion(const char* name) : _name(name), _base(NULL), _top(NULL), _end(NULL), _is_packed(false) {}
133
134 char* allocate(size_t num_bytes, size_t alignment=BytesPerWord) {
135 char* p = (char*)align_up(_top, alignment);
136 char* newtop = p + align_up(num_bytes, alignment);
137 expand_top_to(newtop);
138 memset(p, 0, newtop - p);
139 return p;
140 }
141
142 void append_intptr_t(intptr_t n) {
143 assert(is_aligned(_top, sizeof(intptr_t)), "bad alignment");
144 intptr_t *p = (intptr_t*)_top;
145 char* newtop = _top + sizeof(intptr_t);
146 expand_top_to(newtop);
147 *p = n;
148 }
149
150 char* base() const { return _base; }
151 char* top() const { return _top; }
152 char* end() const { return _end; }
153 size_t reserved() const { return _end - _base; }
154 size_t used() const { return _top - _base; }
155 bool is_packed() const { return _is_packed; }
156 bool is_allocatable() const {
157 return !is_packed() && _base != NULL;
158 }
159
160 void print(size_t total_bytes) const {
161 tty->print_cr("%-3s space: " SIZE_FORMAT_W(9) " [ %4.1f%% of total] out of " SIZE_FORMAT_W(9) " bytes [%5.1f%% used] at " INTPTR_FORMAT,
162 _name, used(), percent_of(used(), total_bytes), reserved(), percent_of(used(), reserved()), p2i(_base));
163 }
164 void print_out_of_space_msg(const char* failing_region, size_t needed_bytes) {
165 tty->print("[%-8s] " PTR_FORMAT " - " PTR_FORMAT " capacity =%9d, allocated =%9d",
166 _name, p2i(_base), p2i(_top), int(_end - _base), int(_top - _base));
167 if (strcmp(_name, failing_region) == 0) {
168 tty->print_cr(" required = %d", int(needed_bytes));
169 } else {
170 tty->cr();
171 }
172 }
173
174 void init(const ReservedSpace* rs) {
175 _base = _top = rs->base();
176 _end = rs->end();
177 }
178 void init(char* b, char* t, char* e) {
179 _base = b;
180 _top = t;
181 _end = e;
182 }
183
184 void pack(DumpRegion* next = NULL) {
185 assert(!is_packed(), "sanity");
186 _end = (char*)align_up(_top, Metaspace::reserve_alignment());
187 _is_packed = true;
188 if (next != NULL) {
189 next->_base = next->_top = this->_end;
190 next->_end = MetaspaceShared::shared_rs()->end();
191 }
192 }
193 bool contains(char* p) {
194 return base() <= p && p < top();
195 }
196 };
197
198
199 DumpRegion _mc_region("mc"), _ro_region("ro"), _rw_region("rw"), _md_region("md"), _od_region("od");
200 size_t _total_string_region_size = 0, _total_open_archive_region_size = 0;
201
202 char* MetaspaceShared::misc_code_space_alloc(size_t num_bytes) {
203 return _mc_region.allocate(num_bytes);
204 }
205
206 char* MetaspaceShared::read_only_space_alloc(size_t num_bytes) {
207 return _ro_region.allocate(num_bytes);
208 }
209
210 void MetaspaceShared::initialize_runtime_shared_and_meta_spaces() {
211 assert(UseSharedSpaces, "Must be called when UseSharedSpaces is enabled");
212
213 // If using shared space, open the file that contains the shared space
214 // and map in the memory before initializing the rest of metaspace (so
215 // the addresses don't conflict)
216 address cds_address = NULL;
217 FileMapInfo* mapinfo = new FileMapInfo();
218
219 // Open the shared archive file, read and validate the header. If
220 // initialization fails, shared spaces [UseSharedSpaces] are
221 // disabled and the file is closed.
222 // Map in spaces now also
223 if (mapinfo->initialize() && map_shared_spaces(mapinfo)) {
224 size_t cds_total = core_spaces_size();
225 cds_address = (address)mapinfo->header()->region_addr(0);
226 #ifdef _LP64
227 if (Metaspace::using_class_space()) {
228 char* cds_end = (char*)(cds_address + cds_total);
229 cds_end = (char *)align_up(cds_end, Metaspace::reserve_alignment());
230 // If UseCompressedClassPointers is set then allocate the metaspace area
231 // above the heap and above the CDS area (if it exists).
232 Metaspace::allocate_metaspace_compressed_klass_ptrs(cds_end, cds_address);
233 // map_heap_regions() compares the current narrow oop and klass encodings
234 // with the archived ones, so it must be done after all encodings are determined.
235 mapinfo->map_heap_regions();
236 }
237 Universe::set_narrow_klass_range(CompressedClassSpaceSize);
238 #endif // _LP64
239 } else {
240 assert(!mapinfo->is_open() && !UseSharedSpaces,
241 "archive file not closed or shared spaces not disabled.");
242 }
243 }
244
245 void MetaspaceShared::initialize_dumptime_shared_and_meta_spaces() {
246 assert(DumpSharedSpaces, "should be called for dump time only");
247 const size_t reserve_alignment = Metaspace::reserve_alignment();
248 bool large_pages = false; // No large pages when dumping the CDS archive.
249 char* shared_base = (char*)align_up((char*)SharedBaseAddress, reserve_alignment);
250
251 #ifdef _LP64
252 // On 64-bit VM, the heap and class space layout will be the same as if
253 // you're running in -Xshare:on mode:
254 //
255 // +-- SharedBaseAddress (default = 0x800000000)
256 // v
257 // +-..---------+---------+ ... +----+----+----+----+----+---------------+
258 // | Heap | Archive | | MC | RW | RO | MD | OD | class space |
259 // +-..---------+---------+ ... +----+----+----+----+----+---------------+
260 // |<-- MaxHeapSize -->| |<-- UnscaledClassSpaceMax = 4GB ------->|
261 //
262 const uint64_t UnscaledClassSpaceMax = (uint64_t(max_juint) + 1);
263 const size_t cds_total = align_down(UnscaledClassSpaceMax, reserve_alignment);
264 #else
265 // We don't support archives larger than 256MB on 32-bit due to limited virtual address space.
266 size_t cds_total = align_down(256*M, reserve_alignment);
267 #endif
268
269 // First try to reserve the space at the specified SharedBaseAddress.
270 _shared_rs = ReservedSpace(cds_total, reserve_alignment, large_pages, shared_base);
271 if (_shared_rs.is_reserved()) {
272 assert(shared_base == 0 || _shared_rs.base() == shared_base, "should match");
273 } else {
274 // Get a mmap region anywhere if the SharedBaseAddress fails.
275 _shared_rs = ReservedSpace(cds_total, reserve_alignment, large_pages);
276 }
277 if (!_shared_rs.is_reserved()) {
278 vm_exit_during_initialization("Unable to reserve memory for shared space",
279 err_msg(SIZE_FORMAT " bytes.", cds_total));
280 }
281
282 #ifdef _LP64
283 // During dump time, we allocate 4GB (UnscaledClassSpaceMax) of space and split it up:
284 // + The upper 1 GB is used as the "temporary compressed class space" -- preload_classes()
285 // will store Klasses into this space.
286 // + The lower 3 GB is used for the archive -- when preload_classes() is done,
287 // ArchiveCompactor will copy the class metadata into this space, first the RW parts,
288 // then the RO parts.
289
290 assert(UseCompressedOops && UseCompressedClassPointers,
291 "UseCompressedOops and UseCompressedClassPointers must be set");
292
293 size_t max_archive_size = align_down(cds_total * 3 / 4, reserve_alignment);
294 ReservedSpace tmp_class_space = _shared_rs.last_part(max_archive_size);
295 CompressedClassSpaceSize = align_down(tmp_class_space.size(), reserve_alignment);
296 _shared_rs = _shared_rs.first_part(max_archive_size);
297
298 // Set up compress class pointers.
299 Universe::set_narrow_klass_base((address)_shared_rs.base());
300 // Set narrow_klass_shift to be LogKlassAlignmentInBytes. This is consistent
301 // with AOT.
302 Universe::set_narrow_klass_shift(LogKlassAlignmentInBytes);
303 // Set the range of klass addresses to 4GB.
304 Universe::set_narrow_klass_range(cds_total);
305
306 Metaspace::initialize_class_space(tmp_class_space);
307 tty->print_cr("narrow_klass_base = " PTR_FORMAT ", narrow_klass_shift = %d",
308 p2i(Universe::narrow_klass_base()), Universe::narrow_klass_shift());
309
310 tty->print_cr("Allocated temporary class space: " SIZE_FORMAT " bytes at " PTR_FORMAT,
311 CompressedClassSpaceSize, p2i(tmp_class_space.base()));
312 #endif
313
314 // Start with 0 committed bytes. The memory will be committed as needed by
315 // MetaspaceShared::commit_shared_space_to().
316 if (!_shared_vs.initialize(_shared_rs, 0)) {
317 vm_exit_during_initialization("Unable to allocate memory for shared space");
318 }
319
320 _mc_region.init(&_shared_rs);
321 tty->print_cr("Allocated shared space: " SIZE_FORMAT " bytes at " PTR_FORMAT,
322 _shared_rs.size(), p2i(_shared_rs.base()));
323 }
324
325 // Called by universe_post_init()
326 void MetaspaceShared::post_initialize(TRAPS) {
327 if (UseSharedSpaces) {
328 int size = FileMapInfo::get_number_of_shared_paths();
329 if (size > 0) {
330 SystemDictionaryShared::allocate_shared_data_arrays(size, THREAD);
331 FileMapInfo::FileMapHeader* header = FileMapInfo::current_info()->header();
332 ClassLoaderExt::init_paths_start_index(header->_app_class_paths_start_index);
333 ClassLoaderExt::init_app_module_paths_start_index(header->_app_module_paths_start_index);
334 }
335 }
336
337 if (DumpSharedSpaces) {
338 if (SharedArchiveConfigFile) {
339 read_extra_data(SharedArchiveConfigFile, THREAD);
340 }
341 }
342 }
343
344 void MetaspaceShared::read_extra_data(const char* filename, TRAPS) {
345 HashtableTextDump reader(filename);
346 reader.check_version("VERSION: 1.0");
347
348 while (reader.remain() > 0) {
349 int utf8_length;
350 int prefix_type = reader.scan_prefix(&utf8_length);
351 ResourceMark rm(THREAD);
352 char* utf8_buffer = NEW_RESOURCE_ARRAY(char, utf8_length);
353 reader.get_utf8(utf8_buffer, utf8_length);
354
355 if (prefix_type == HashtableTextDump::SymbolPrefix) {
356 SymbolTable::new_symbol(utf8_buffer, utf8_length, THREAD);
357 } else{
358 assert(prefix_type == HashtableTextDump::StringPrefix, "Sanity");
359 utf8_buffer[utf8_length] = '\0';
360 oop s = StringTable::intern(utf8_buffer, THREAD);
361 }
362 }
363 }
364
365 void MetaspaceShared::commit_shared_space_to(char* newtop) {
366 assert(DumpSharedSpaces, "dump-time only");
367 char* base = _shared_rs.base();
368 size_t need_committed_size = newtop - base;
369 size_t has_committed_size = _shared_vs.committed_size();
370 if (need_committed_size < has_committed_size) {
371 return;
372 }
373
374 size_t min_bytes = need_committed_size - has_committed_size;
375 size_t preferred_bytes = 1 * M;
376 size_t uncommitted = _shared_vs.reserved_size() - has_committed_size;
377
378 size_t commit = MAX2(min_bytes, preferred_bytes);
379 assert(commit <= uncommitted, "sanity");
380
381 bool result = _shared_vs.expand_by(commit, false);
382 if (!result) {
383 vm_exit_during_initialization(err_msg("Failed to expand shared space to " SIZE_FORMAT " bytes",
384 need_committed_size));
385 }
386
387 log_info(cds)("Expanding shared spaces by " SIZE_FORMAT_W(7) " bytes [total " SIZE_FORMAT_W(9) " bytes ending at %p]",
388 commit, _shared_vs.actual_committed_size(), _shared_vs.high());
389 }
390
391 // Read/write a data stream for restoring/preserving metadata pointers and
392 // miscellaneous data from/to the shared archive file.
393
394 void MetaspaceShared::serialize(SerializeClosure* soc) {
395 int tag = 0;
396 soc->do_tag(--tag);
397
398 // Verify the sizes of various metadata in the system.
399 soc->do_tag(sizeof(Method));
400 soc->do_tag(sizeof(ConstMethod));
401 soc->do_tag(arrayOopDesc::base_offset_in_bytes(T_BYTE));
402 soc->do_tag(sizeof(ConstantPool));
403 soc->do_tag(sizeof(ConstantPoolCache));
404 soc->do_tag(objArrayOopDesc::base_offset_in_bytes());
405 soc->do_tag(typeArrayOopDesc::base_offset_in_bytes(T_BYTE));
406 soc->do_tag(sizeof(Symbol));
407
408 // Dump/restore miscellaneous metadata.
409 Universe::serialize(soc, true);
410 soc->do_tag(--tag);
411
412 // Dump/restore references to commonly used names and signatures.
413 vmSymbols::serialize(soc);
414 soc->do_tag(--tag);
415
416 // Dump/restore the symbol and string tables
417 SymbolTable::serialize(soc);
418 StringTable::serialize(soc);
419 soc->do_tag(--tag);
420
421 serialize_well_known_classes(soc);
422 soc->do_tag(--tag);
423
424 soc->do_tag(666);
425 }
426
427 void MetaspaceShared::serialize_well_known_classes(SerializeClosure* soc) {
428 java_lang_Class::serialize(soc);
429 java_lang_String::serialize(soc);
430 java_lang_System::serialize(soc);
431 java_lang_ClassLoader::serialize(soc);
432 java_lang_Throwable::serialize(soc);
433 java_lang_Thread::serialize(soc);
434 java_lang_ThreadGroup::serialize(soc);
435 java_lang_AssertionStatusDirectives::serialize(soc);
436 java_lang_ref_SoftReference::serialize(soc);
437 java_lang_invoke_MethodHandle::serialize(soc);
438 java_lang_invoke_DirectMethodHandle::serialize(soc);
439 java_lang_invoke_MemberName::serialize(soc);
440 java_lang_invoke_ResolvedMethodName::serialize(soc);
441 java_lang_invoke_LambdaForm::serialize(soc);
442 java_lang_invoke_MethodType::serialize(soc);
443 java_lang_invoke_CallSite::serialize(soc);
444 java_lang_invoke_MethodHandleNatives_CallSiteContext::serialize(soc);
445 java_security_AccessControlContext::serialize(soc);
446 java_lang_reflect_AccessibleObject::serialize(soc);
447 java_lang_reflect_Method::serialize(soc);
448 java_lang_reflect_Constructor::serialize(soc);
449 java_lang_reflect_Field::serialize(soc);
450 java_nio_Buffer::serialize(soc);
451 reflect_ConstantPool::serialize(soc);
452 reflect_UnsafeStaticFieldAccessorImpl::serialize(soc);
453 java_lang_reflect_Parameter::serialize(soc);
454 java_lang_Module::serialize(soc);
455 java_lang_StackTraceElement::serialize(soc);
456 java_lang_StackFrameInfo::serialize(soc);
457 java_lang_LiveStackFrameInfo::serialize(soc);
458 }
459
460 address MetaspaceShared::cds_i2i_entry_code_buffers(size_t total_size) {
461 if (DumpSharedSpaces) {
462 if (_cds_i2i_entry_code_buffers == NULL) {
463 _cds_i2i_entry_code_buffers = (address)misc_code_space_alloc(total_size);
464 _cds_i2i_entry_code_buffers_size = total_size;
465 }
466 } else if (UseSharedSpaces) {
467 assert(_cds_i2i_entry_code_buffers != NULL, "must already been initialized");
468 } else {
469 return NULL;
470 }
471
472 assert(_cds_i2i_entry_code_buffers_size == total_size, "must not change");
473 return _cds_i2i_entry_code_buffers;
474 }
475
476 // CDS code for dumping shared archive.
477
478 // Global object for holding classes that have been loaded. Since this
479 // is run at a safepoint just before exit, this is the entire set of classes.
480 static GrowableArray<Klass*>* _global_klass_objects;
481
482 static void collect_array_classes(Klass* k) {
483 _global_klass_objects->append_if_missing(k);
484 if (k->is_array_klass()) {
485 // Add in the array classes too
486 ArrayKlass* ak = ArrayKlass::cast(k);
487 Klass* h = ak->higher_dimension();
488 if (h != NULL) {
489 h->array_klasses_do(collect_array_classes);
490 }
491 }
492 }
493
494 class CollectClassesClosure : public KlassClosure {
495 void do_klass(Klass* k) {
496 if (!(k->is_instance_klass() && InstanceKlass::cast(k)->is_in_error_state())) {
497 if (k->is_instance_klass() && InstanceKlass::cast(k)->signers() != NULL) {
498 // Mark any class with signers and don't add to the _global_klass_objects
499 k->set_has_signer_and_not_archived();
500 } else {
501 _global_klass_objects->append_if_missing(k);
502 }
503 }
504 if (k->is_array_klass()) {
505 // Add in the array classes too
506 ArrayKlass* ak = ArrayKlass::cast(k);
507 Klass* h = ak->higher_dimension();
508 if (h != NULL) {
509 h->array_klasses_do(collect_array_classes);
510 }
511 }
512 }
513 };
514
515 static void remove_unshareable_in_classes() {
516 for (int i = 0; i < _global_klass_objects->length(); i++) {
517 Klass* k = _global_klass_objects->at(i);
518 if (!k->is_objArray_klass()) {
519 // InstanceKlass and TypeArrayKlass will in turn call remove_unshareable_info
520 // on their array classes.
521 assert(k->is_instance_klass() || k->is_typeArray_klass(), "must be");
522 k->remove_unshareable_info();
523 }
524 }
525 }
526
527 static void remove_java_mirror_in_classes() {
528 for (int i = 0; i < _global_klass_objects->length(); i++) {
529 Klass* k = _global_klass_objects->at(i);
530 if (!k->is_objArray_klass()) {
531 // InstanceKlass and TypeArrayKlass will in turn call remove_unshareable_info
532 // on their array classes.
533 assert(k->is_instance_klass() || k->is_typeArray_klass(), "must be");
534 k->remove_java_mirror();
535 }
536 }
537 }
538
539 static void clear_basic_type_mirrors() {
540 assert(!MetaspaceShared::is_heap_object_archiving_allowed(), "Sanity");
541 Universe::set_int_mirror(NULL);
542 Universe::set_float_mirror(NULL);
543 Universe::set_double_mirror(NULL);
544 Universe::set_byte_mirror(NULL);
545 Universe::set_bool_mirror(NULL);
546 Universe::set_char_mirror(NULL);
547 Universe::set_long_mirror(NULL);
548 Universe::set_short_mirror(NULL);
549 Universe::set_void_mirror(NULL);
550 }
551
552 static void rewrite_nofast_bytecode(Method* method) {
553 BytecodeStream bcs(method);
554 while (!bcs.is_last_bytecode()) {
555 Bytecodes::Code opcode = bcs.next();
556 switch (opcode) {
557 case Bytecodes::_getfield: *bcs.bcp() = Bytecodes::_nofast_getfield; break;
558 case Bytecodes::_putfield: *bcs.bcp() = Bytecodes::_nofast_putfield; break;
559 case Bytecodes::_aload_0: *bcs.bcp() = Bytecodes::_nofast_aload_0; break;
560 case Bytecodes::_iload: {
561 if (!bcs.is_wide()) {
562 *bcs.bcp() = Bytecodes::_nofast_iload;
563 }
564 break;
565 }
566 default: break;
567 }
568 }
569 }
570
571 // Walk all methods in the class list to ensure that they won't be modified at
572 // run time. This includes:
573 // [1] Rewrite all bytecodes as needed, so that the ConstMethod* will not be modified
574 // at run time by RewriteBytecodes/RewriteFrequentPairs
575 // [2] Assign a fingerprint, so one doesn't need to be assigned at run-time.
576 static void rewrite_nofast_bytecodes_and_calculate_fingerprints() {
577 for (int i = 0; i < _global_klass_objects->length(); i++) {
578 Klass* k = _global_klass_objects->at(i);
579 if (k->is_instance_klass()) {
580 InstanceKlass* ik = InstanceKlass::cast(k);
581 for (int i = 0; i < ik->methods()->length(); i++) {
582 Method* m = ik->methods()->at(i);
583 rewrite_nofast_bytecode(m);
584 Fingerprinter fp(m);
585 // The side effect of this call sets method's fingerprint field.
586 fp.fingerprint();
587 }
588 }
589 }
590 }
591
592 static void relocate_cached_class_file() {
593 for (int i = 0; i < _global_klass_objects->length(); i++) {
594 Klass* k = _global_klass_objects->at(i);
595 if (k->is_instance_klass()) {
596 InstanceKlass* ik = InstanceKlass::cast(k);
597 JvmtiCachedClassFileData* p = ik->get_archived_class_data();
598 if (p != NULL) {
599 int size = offset_of(JvmtiCachedClassFileData, data) + p->length;
600 JvmtiCachedClassFileData* q = (JvmtiCachedClassFileData*)_od_region.allocate(size);
601 q->length = p->length;
602 memcpy(q->data, p->data, p->length);
603 ik->set_archived_class_data(q);
604 }
605 }
606 }
607 }
608
609 NOT_PRODUCT(
610 static void assert_not_anonymous_class(InstanceKlass* k) {
611 assert(!(k->is_anonymous()), "cannot archive anonymous classes");
612 }
613
614 // Anonymous classes are not stored inside any dictionaries. They are created by
615 // SystemDictionary::parse_stream() with a non-null host_klass.
616 static void assert_no_anonymoys_classes_in_dictionaries() {
617 ClassLoaderDataGraph::dictionary_classes_do(assert_not_anonymous_class);
618 })
619
620 // Objects of the Metadata types (such as Klass and ConstantPool) have C++ vtables.
621 // (In GCC this is the field <Type>::_vptr, i.e., first word in the object.)
622 //
623 // Addresses of the vtables and the methods may be different across JVM runs,
624 // if libjvm.so is dynamically loaded at a different base address.
625 //
626 // To ensure that the Metadata objects in the CDS archive always have the correct vtable:
627 //
628 // + at dump time: we redirect the _vptr to point to our own vtables inside
629 // the CDS image
630 // + at run time: we clone the actual contents of the vtables from libjvm.so
631 // into our own tables.
632
633 // Currently, the archive contain ONLY the following types of objects that have C++ vtables.
634 #define CPP_VTABLE_PATCH_TYPES_DO(f) \
635 f(ConstantPool) \
636 f(InstanceKlass) \
637 f(InstanceClassLoaderKlass) \
638 f(InstanceMirrorKlass) \
639 f(InstanceRefKlass) \
640 f(Method) \
641 f(ObjArrayKlass) \
642 f(TypeArrayKlass)
643
644 class CppVtableInfo {
645 intptr_t _vtable_size;
646 intptr_t _cloned_vtable[1];
647 public:
648 static int num_slots(int vtable_size) {
649 return 1 + vtable_size; // Need to add the space occupied by _vtable_size;
650 }
651 int vtable_size() { return int(uintx(_vtable_size)); }
652 void set_vtable_size(int n) { _vtable_size = intptr_t(n); }
653 intptr_t* cloned_vtable() { return &_cloned_vtable[0]; }
654 void zero() { memset(_cloned_vtable, 0, sizeof(intptr_t) * vtable_size()); }
655 // Returns the address of the next CppVtableInfo that can be placed immediately after this CppVtableInfo
656 static size_t byte_size(int vtable_size) {
657 CppVtableInfo i;
658 return pointer_delta(&i._cloned_vtable[vtable_size], &i, sizeof(u1));
659 }
660 };
661
662 template <class T> class CppVtableCloner : public T {
663 static intptr_t* vtable_of(Metadata& m) {
664 return *((intptr_t**)&m);
665 }
666 static CppVtableInfo* _info;
667
668 static int get_vtable_length(const char* name);
669
670 public:
671 // Allocate and initialize the C++ vtable, starting from top, but do not go past end.
672 static intptr_t* allocate(const char* name);
673
674 // Clone the vtable to ...
675 static intptr_t* clone_vtable(const char* name, CppVtableInfo* info);
676
677 static void zero_vtable_clone() {
678 assert(DumpSharedSpaces, "dump-time only");
679 _info->zero();
680 }
681
682 // Switch the vtable pointer to point to the cloned vtable.
683 static void patch(Metadata* obj) {
684 assert(DumpSharedSpaces, "dump-time only");
685 *(void**)obj = (void*)(_info->cloned_vtable());
686 }
687
688 static bool is_valid_shared_object(const T* obj) {
689 intptr_t* vptr = *(intptr_t**)obj;
690 return vptr == _info->cloned_vtable();
691 }
692 };
693
694 template <class T> CppVtableInfo* CppVtableCloner<T>::_info = NULL;
695
696 template <class T>
697 intptr_t* CppVtableCloner<T>::allocate(const char* name) {
698 assert(is_aligned(_md_region.top(), sizeof(intptr_t)), "bad alignment");
699 int n = get_vtable_length(name);
700 _info = (CppVtableInfo*)_md_region.allocate(CppVtableInfo::byte_size(n), sizeof(intptr_t));
701 _info->set_vtable_size(n);
702
703 intptr_t* p = clone_vtable(name, _info);
704 assert((char*)p == _md_region.top(), "must be");
705
706 return p;
707 }
708
709 template <class T>
710 intptr_t* CppVtableCloner<T>::clone_vtable(const char* name, CppVtableInfo* info) {
711 if (!DumpSharedSpaces) {
712 assert(_info == 0, "_info is initialized only at dump time");
713 _info = info; // Remember it -- it will be used by MetaspaceShared::is_valid_shared_method()
714 }
715 T tmp; // Allocate temporary dummy metadata object to get to the original vtable.
716 int n = info->vtable_size();
717 intptr_t* srcvtable = vtable_of(tmp);
718 intptr_t* dstvtable = info->cloned_vtable();
719
720 // We already checked (and, if necessary, adjusted n) when the vtables were allocated, so we are
721 // safe to do memcpy.
722 log_debug(cds, vtables)("Copying %3d vtable entries for %s", n, name);
723 memcpy(dstvtable, srcvtable, sizeof(intptr_t) * n);
724 return dstvtable + n;
725 }
726
727 // To determine the size of the vtable for each type, we use the following
728 // trick by declaring 2 subclasses:
729 //
730 // class CppVtableTesterA: public InstanceKlass {virtual int last_virtual_method() {return 1;} };
731 // class CppVtableTesterB: public InstanceKlass {virtual void* last_virtual_method() {return NULL}; };
732 //
733 // CppVtableTesterA and CppVtableTesterB's vtables have the following properties:
734 // - Their size (N+1) is exactly one more than the size of InstanceKlass's vtable (N)
735 // - The first N entries have are exactly the same as in InstanceKlass's vtable.
736 // - Their last entry is different.
737 //
738 // So to determine the value of N, we just walk CppVtableTesterA and CppVtableTesterB's tables
739 // and find the first entry that's different.
740 //
741 // This works on all C++ compilers supported by Oracle, but you may need to tweak it for more
742 // esoteric compilers.
743
744 template <class T> class CppVtableTesterB: public T {
745 public:
746 virtual int last_virtual_method() {return 1;}
747 };
748
749 template <class T> class CppVtableTesterA : public T {
750 public:
751 virtual void* last_virtual_method() {
752 // Make this different than CppVtableTesterB::last_virtual_method so the C++
753 // compiler/linker won't alias the two functions.
754 return NULL;
755 }
756 };
757
758 template <class T>
759 int CppVtableCloner<T>::get_vtable_length(const char* name) {
760 CppVtableTesterA<T> a;
761 CppVtableTesterB<T> b;
762
763 intptr_t* avtable = vtable_of(a);
764 intptr_t* bvtable = vtable_of(b);
765
766 // Start at slot 1, because slot 0 may be RTTI (on Solaris/Sparc)
767 int vtable_len = 1;
768 for (; ; vtable_len++) {
769 if (avtable[vtable_len] != bvtable[vtable_len]) {
770 break;
771 }
772 }
773 log_debug(cds, vtables)("Found %3d vtable entries for %s", vtable_len, name);
774
775 return vtable_len;
776 }
777
778 #define ALLOC_CPP_VTABLE_CLONE(c) \
779 CppVtableCloner<c>::allocate(#c);
780
781 #define CLONE_CPP_VTABLE(c) \
782 p = CppVtableCloner<c>::clone_vtable(#c, (CppVtableInfo*)p);
783
784 #define ZERO_CPP_VTABLE(c) \
785 CppVtableCloner<c>::zero_vtable_clone();
786
787 // This can be called at both dump time and run time.
788 intptr_t* MetaspaceShared::clone_cpp_vtables(intptr_t* p) {
789 assert(DumpSharedSpaces || UseSharedSpaces, "sanity");
790 CPP_VTABLE_PATCH_TYPES_DO(CLONE_CPP_VTABLE);
791 return p;
792 }
793
794 void MetaspaceShared::zero_cpp_vtable_clones_for_writing() {
795 assert(DumpSharedSpaces, "dump-time only");
796 CPP_VTABLE_PATCH_TYPES_DO(ZERO_CPP_VTABLE);
797 }
798
799 // Allocate and initialize the C++ vtables, starting from top, but do not go past end.
800 void MetaspaceShared::allocate_cpp_vtable_clones() {
801 assert(DumpSharedSpaces, "dump-time only");
802 // Layout (each slot is a intptr_t):
803 // [number of slots in the first vtable = n1]
804 // [ <n1> slots for the first vtable]
805 // [number of slots in the first second = n2]
806 // [ <n2> slots for the second vtable]
807 // ...
808 // The order of the vtables is the same as the CPP_VTAB_PATCH_TYPES_DO macro.
809 CPP_VTABLE_PATCH_TYPES_DO(ALLOC_CPP_VTABLE_CLONE);
810 }
811
812 // Switch the vtable pointer to point to the cloned vtable. We assume the
813 // vtable pointer is in first slot in object.
814 void MetaspaceShared::patch_cpp_vtable_pointers() {
815 int n = _global_klass_objects->length();
816 for (int i = 0; i < n; i++) {
817 Klass* obj = _global_klass_objects->at(i);
818 if (obj->is_instance_klass()) {
819 InstanceKlass* ik = InstanceKlass::cast(obj);
820 if (ik->is_class_loader_instance_klass()) {
821 CppVtableCloner<InstanceClassLoaderKlass>::patch(ik);
822 } else if (ik->is_reference_instance_klass()) {
823 CppVtableCloner<InstanceRefKlass>::patch(ik);
824 } else if (ik->is_mirror_instance_klass()) {
825 CppVtableCloner<InstanceMirrorKlass>::patch(ik);
826 } else {
827 CppVtableCloner<InstanceKlass>::patch(ik);
828 }
829 ConstantPool* cp = ik->constants();
830 CppVtableCloner<ConstantPool>::patch(cp);
831 for (int j = 0; j < ik->methods()->length(); j++) {
832 Method* m = ik->methods()->at(j);
833 CppVtableCloner<Method>::patch(m);
834 assert(CppVtableCloner<Method>::is_valid_shared_object(m), "must be");
835 }
836 } else if (obj->is_objArray_klass()) {
837 CppVtableCloner<ObjArrayKlass>::patch(obj);
838 } else {
839 assert(obj->is_typeArray_klass(), "sanity");
840 CppVtableCloner<TypeArrayKlass>::patch(obj);
841 }
842 }
843 }
844
845 bool MetaspaceShared::is_valid_shared_method(const Method* m) {
846 assert(is_in_shared_metaspace(m), "must be");
847 return CppVtableCloner<Method>::is_valid_shared_object(m);
848 }
849
850 // Closure for serializing initialization data out to a data area to be
851 // written to the shared file.
852
853 class WriteClosure : public SerializeClosure {
854 private:
855 DumpRegion* _dump_region;
856
857 public:
858 WriteClosure(DumpRegion* r) {
859 _dump_region = r;
860 }
861
862 void do_ptr(void** p) {
863 _dump_region->append_intptr_t((intptr_t)*p);
864 }
865
866 void do_u4(u4* p) {
867 void* ptr = (void*)(uintx(*p));
868 do_ptr(&ptr);
869 }
870
871 void do_tag(int tag) {
872 _dump_region->append_intptr_t((intptr_t)tag);
873 }
874
875 void do_oop(oop* o) {
876 if (*o == NULL) {
877 _dump_region->append_intptr_t(0);
878 } else {
879 assert(MetaspaceShared::is_heap_object_archiving_allowed(),
880 "Archiving heap object is not allowed");
881 _dump_region->append_intptr_t(
882 (intptr_t)CompressedOops::encode_not_null(*o));
883 }
884 }
885
886 void do_region(u_char* start, size_t size) {
887 assert((intptr_t)start % sizeof(intptr_t) == 0, "bad alignment");
888 assert(size % sizeof(intptr_t) == 0, "bad size");
889 do_tag((int)size);
890 while (size > 0) {
891 _dump_region->append_intptr_t(*(intptr_t*)start);
892 start += sizeof(intptr_t);
893 size -= sizeof(intptr_t);
894 }
895 }
896
897 bool reading() const { return false; }
898 };
899
900 // This is for dumping detailed statistics for the allocations
901 // in the shared spaces.
902 class DumpAllocStats : public ResourceObj {
903 public:
904
905 // Here's poor man's enum inheritance
906 #define SHAREDSPACE_OBJ_TYPES_DO(f) \
907 METASPACE_OBJ_TYPES_DO(f) \
908 f(SymbolHashentry) \
909 f(SymbolBucket) \
910 f(StringHashentry) \
911 f(StringBucket) \
912 f(Other)
913
914 enum Type {
915 // Types are MetaspaceObj::ClassType, MetaspaceObj::SymbolType, etc
916 SHAREDSPACE_OBJ_TYPES_DO(METASPACE_OBJ_TYPE_DECLARE)
917 _number_of_types
918 };
919
920 static const char * type_name(Type type) {
921 switch(type) {
922 SHAREDSPACE_OBJ_TYPES_DO(METASPACE_OBJ_TYPE_NAME_CASE)
923 default:
924 ShouldNotReachHere();
925 return NULL;
926 }
927 }
928
929 public:
930 enum { RO = 0, RW = 1 };
931
932 int _counts[2][_number_of_types];
933 int _bytes [2][_number_of_types];
934
935 DumpAllocStats() {
936 memset(_counts, 0, sizeof(_counts));
937 memset(_bytes, 0, sizeof(_bytes));
938 };
939
940 void record(MetaspaceObj::Type type, int byte_size, bool read_only) {
941 assert(int(type) >= 0 && type < MetaspaceObj::_number_of_types, "sanity");
942 int which = (read_only) ? RO : RW;
943 _counts[which][type] ++;
944 _bytes [which][type] += byte_size;
945 }
946
947 void record_other_type(int byte_size, bool read_only) {
948 int which = (read_only) ? RO : RW;
949 _bytes [which][OtherType] += byte_size;
950 }
951 void print_stats(int ro_all, int rw_all, int mc_all, int md_all);
952 };
953
954 void DumpAllocStats::print_stats(int ro_all, int rw_all, int mc_all, int md_all) {
955 // Calculate size of data that was not allocated by Metaspace::allocate()
956 MetaspaceSharedStats *stats = MetaspaceShared::stats();
957
958 // symbols
959 _counts[RO][SymbolHashentryType] = stats->symbol.hashentry_count;
960 _bytes [RO][SymbolHashentryType] = stats->symbol.hashentry_bytes;
961
962 _counts[RO][SymbolBucketType] = stats->symbol.bucket_count;
963 _bytes [RO][SymbolBucketType] = stats->symbol.bucket_bytes;
964
965 // strings
966 _counts[RO][StringHashentryType] = stats->string.hashentry_count;
967 _bytes [RO][StringHashentryType] = stats->string.hashentry_bytes;
968
969 _counts[RO][StringBucketType] = stats->string.bucket_count;
970 _bytes [RO][StringBucketType] = stats->string.bucket_bytes;
971
972 // TODO: count things like dictionary, vtable, etc
973 _bytes[RW][OtherType] += mc_all + md_all;
974 rw_all += mc_all + md_all; // mc/md are mapped Read/Write
975
976 // prevent divide-by-zero
977 if (ro_all < 1) {
978 ro_all = 1;
979 }
980 if (rw_all < 1) {
981 rw_all = 1;
982 }
983
984 int all_ro_count = 0;
985 int all_ro_bytes = 0;
986 int all_rw_count = 0;
987 int all_rw_bytes = 0;
988
989 // To make fmt_stats be a syntactic constant (for format warnings), use #define.
990 #define fmt_stats "%-20s: %8d %10d %5.1f | %8d %10d %5.1f | %8d %10d %5.1f"
991 const char *sep = "--------------------+---------------------------+---------------------------+--------------------------";
992 const char *hdr = " ro_cnt ro_bytes % | rw_cnt rw_bytes % | all_cnt all_bytes %";
993
994 LogMessage(cds) msg;
995
996 msg.info("Detailed metadata info (excluding od/st regions; rw stats include md/mc regions):");
997 msg.info("%s", hdr);
998 msg.info("%s", sep);
999 for (int type = 0; type < int(_number_of_types); type ++) {
1000 const char *name = type_name((Type)type);
1001 int ro_count = _counts[RO][type];
1002 int ro_bytes = _bytes [RO][type];
1003 int rw_count = _counts[RW][type];
1004 int rw_bytes = _bytes [RW][type];
1005 int count = ro_count + rw_count;
1006 int bytes = ro_bytes + rw_bytes;
1007
1008 double ro_perc = percent_of(ro_bytes, ro_all);
1009 double rw_perc = percent_of(rw_bytes, rw_all);
1010 double perc = percent_of(bytes, ro_all + rw_all);
1011
1012 msg.info(fmt_stats, name,
1013 ro_count, ro_bytes, ro_perc,
1014 rw_count, rw_bytes, rw_perc,
1015 count, bytes, perc);
1016
1017 all_ro_count += ro_count;
1018 all_ro_bytes += ro_bytes;
1019 all_rw_count += rw_count;
1020 all_rw_bytes += rw_bytes;
1021 }
1022
1023 int all_count = all_ro_count + all_rw_count;
1024 int all_bytes = all_ro_bytes + all_rw_bytes;
1025
1026 double all_ro_perc = percent_of(all_ro_bytes, ro_all);
1027 double all_rw_perc = percent_of(all_rw_bytes, rw_all);
1028 double all_perc = percent_of(all_bytes, ro_all + rw_all);
1029
1030 msg.info("%s", sep);
1031 msg.info(fmt_stats, "Total",
1032 all_ro_count, all_ro_bytes, all_ro_perc,
1033 all_rw_count, all_rw_bytes, all_rw_perc,
1034 all_count, all_bytes, all_perc);
1035
1036 assert(all_ro_bytes == ro_all, "everything should have been counted");
1037 assert(all_rw_bytes == rw_all, "everything should have been counted");
1038
1039 #undef fmt_stats
1040 }
1041
1042 // Populate the shared space.
1043
1044 class VM_PopulateDumpSharedSpace: public VM_Operation {
1045 private:
1046 GrowableArray<MemRegion> *_closed_archive_heap_regions;
1047 GrowableArray<MemRegion> *_open_archive_heap_regions;
1048
1049 void dump_java_heap_objects() NOT_CDS_JAVA_HEAP_RETURN;
1050 void dump_symbols();
1051 char* dump_read_only_tables();
1052 void print_region_stats();
1053 void print_heap_region_stats(GrowableArray<MemRegion> *heap_mem,
1054 const char *name, const size_t total_size);
1055 public:
1056
1057 VMOp_Type type() const { return VMOp_PopulateDumpSharedSpace; }
1058 void doit(); // outline because gdb sucks
1059 static void write_region(FileMapInfo* mapinfo, int region, DumpRegion* space, bool read_only, bool allow_exec);
1060 bool allow_nested_vm_operations() const { return true; }
1061 }; // class VM_PopulateDumpSharedSpace
1062
1063 class SortedSymbolClosure: public SymbolClosure {
1064 GrowableArray<Symbol*> _symbols;
1065 virtual void do_symbol(Symbol** sym) {
1066 assert((*sym)->is_permanent(), "archived symbols must be permanent");
1067 _symbols.append(*sym);
1068 }
1069 static int compare_symbols_by_address(Symbol** a, Symbol** b) {
1070 if (a[0] < b[0]) {
1071 return -1;
1072 } else if (a[0] == b[0]) {
1073 return 0;
1074 } else {
1075 return 1;
1076 }
1077 }
1078
1079 public:
1080 SortedSymbolClosure() {
1081 SymbolTable::symbols_do(this);
1082 _symbols.sort(compare_symbols_by_address);
1083 }
1084 GrowableArray<Symbol*>* get_sorted_symbols() {
1085 return &_symbols;
1086 }
1087 };
1088
1089 // ArchiveCompactor --
1090 //
1091 // This class is the central piece of shared archive compaction -- all metaspace data are
1092 // initially allocated outside of the shared regions. ArchiveCompactor copies the
1093 // metaspace data into their final location in the shared regions.
1094
1095 class ArchiveCompactor : AllStatic {
1096 static DumpAllocStats* _alloc_stats;
1097 static SortedSymbolClosure* _ssc;
1098
1099 static unsigned my_hash(const address& a) {
1100 return primitive_hash<address>(a);
1101 }
1102 static bool my_equals(const address& a0, const address& a1) {
1103 return primitive_equals<address>(a0, a1);
1104 }
1105 typedef ResourceHashtable<
1106 address, address,
1107 ArchiveCompactor::my_hash, // solaris compiler doesn't like: primitive_hash<address>
1108 ArchiveCompactor::my_equals, // solaris compiler doesn't like: primitive_equals<address>
1109 16384, ResourceObj::C_HEAP> RelocationTable;
1110 static RelocationTable* _new_loc_table;
1111
1112 public:
1113 static void initialize() {
1114 _alloc_stats = new(ResourceObj::C_HEAP, mtInternal)DumpAllocStats;
1115 _new_loc_table = new(ResourceObj::C_HEAP, mtInternal)RelocationTable;
1116 }
1117 static DumpAllocStats* alloc_stats() {
1118 return _alloc_stats;
1119 }
1120
1121 static void allocate(MetaspaceClosure::Ref* ref, bool read_only) {
1122 address obj = ref->obj();
1123 int bytes = ref->size() * BytesPerWord;
1124 char* p;
1125 size_t alignment = BytesPerWord;
1126 char* oldtop;
1127 char* newtop;
1128
1129 if (read_only) {
1130 oldtop = _ro_region.top();
1131 p = _ro_region.allocate(bytes, alignment);
1132 newtop = _ro_region.top();
1133 } else {
1134 oldtop = _rw_region.top();
1135 p = _rw_region.allocate(bytes, alignment);
1136 newtop = _rw_region.top();
1137 }
1138 memcpy(p, obj, bytes);
1139 bool isnew = _new_loc_table->put(obj, (address)p);
1140 log_trace(cds)("Copy: " PTR_FORMAT " ==> " PTR_FORMAT " %d", p2i(obj), p2i(p), bytes);
1141 assert(isnew, "must be");
1142
1143 _alloc_stats->record(ref->msotype(), int(newtop - oldtop), read_only);
1144 if (ref->msotype() == MetaspaceObj::SymbolType) {
1145 uintx delta = MetaspaceShared::object_delta(p);
1146 if (delta > MAX_SHARED_DELTA) {
1147 // This is just a sanity check and should not appear in any real world usage. This
1148 // happens only if you allocate more than 2GB of Symbols and would require
1149 // millions of shared classes.
1150 vm_exit_during_initialization("Too many Symbols in the CDS archive",
1151 "Please reduce the number of shared classes.");
1152 }
1153 }
1154 }
1155
1156 static address get_new_loc(MetaspaceClosure::Ref* ref) {
1157 address* pp = _new_loc_table->get(ref->obj());
1158 assert(pp != NULL, "must be");
1159 return *pp;
1160 }
1161
1162 private:
1163 // Makes a shallow copy of visited MetaspaceObj's
1164 class ShallowCopier: public UniqueMetaspaceClosure {
1165 bool _read_only;
1166 public:
1167 ShallowCopier(bool read_only) : _read_only(read_only) {}
1168
1169 virtual void do_unique_ref(Ref* ref, bool read_only) {
1170 if (read_only == _read_only) {
1171 allocate(ref, read_only);
1172 }
1173 }
1174 };
1175
1176 // Relocate embedded pointers within a MetaspaceObj's shallow copy
1177 class ShallowCopyEmbeddedRefRelocator: public UniqueMetaspaceClosure {
1178 public:
1179 virtual void do_unique_ref(Ref* ref, bool read_only) {
1180 address new_loc = get_new_loc(ref);
1181 RefRelocator refer;
1182 ref->metaspace_pointers_do_at(&refer, new_loc);
1183 }
1184 };
1185
1186 // Relocate a reference to point to its shallow copy
1187 class RefRelocator: public MetaspaceClosure {
1188 public:
1189 virtual bool do_ref(Ref* ref, bool read_only) {
1190 if (ref->not_null()) {
1191 ref->update(get_new_loc(ref));
1192 }
1193 return false; // Do not recurse.
1194 }
1195 };
1196
1197 #ifdef ASSERT
1198 class IsRefInArchiveChecker: public MetaspaceClosure {
1199 public:
1200 virtual bool do_ref(Ref* ref, bool read_only) {
1201 if (ref->not_null()) {
1202 char* obj = (char*)ref->obj();
1203 assert(_ro_region.contains(obj) || _rw_region.contains(obj),
1204 "must be relocated to point to CDS archive");
1205 }
1206 return false; // Do not recurse.
1207 }
1208 };
1209 #endif
1210
1211 public:
1212 static void copy_and_compact() {
1213 // We should no longer allocate anything from the metaspace, so that
1214 // we can have a stable set of MetaspaceObjs to work with.
1215 Metaspace::freeze();
1216
1217 ResourceMark rm;
1218 SortedSymbolClosure the_ssc; // StackObj
1219 _ssc = &the_ssc;
1220
1221 tty->print_cr("Scanning all metaspace objects ... ");
1222 {
1223 // allocate and shallow-copy RW objects, immediately following the MC region
1224 tty->print_cr("Allocating RW objects ... ");
1225 _mc_region.pack(&_rw_region);
1226
1227 ResourceMark rm;
1228 ShallowCopier rw_copier(false);
1229 iterate_roots(&rw_copier);
1230 }
1231 {
1232 // allocate and shallow-copy of RO object, immediately following the RW region
1233 tty->print_cr("Allocating RO objects ... ");
1234 _rw_region.pack(&_ro_region);
1235
1236 ResourceMark rm;
1237 ShallowCopier ro_copier(true);
1238 iterate_roots(&ro_copier);
1239 }
1240 {
1241 tty->print_cr("Relocating embedded pointers ... ");
1242 ResourceMark rm;
1243 ShallowCopyEmbeddedRefRelocator emb_reloc;
1244 iterate_roots(&emb_reloc);
1245 }
1246 {
1247 tty->print_cr("Relocating external roots ... ");
1248 ResourceMark rm;
1249 RefRelocator ext_reloc;
1250 iterate_roots(&ext_reloc);
1251 }
1252
1253 #ifdef ASSERT
1254 {
1255 tty->print_cr("Verifying external roots ... ");
1256 ResourceMark rm;
1257 IsRefInArchiveChecker checker;
1258 iterate_roots(&checker);
1259 }
1260 #endif
1261
1262
1263 // cleanup
1264 _ssc = NULL;
1265 }
1266
1267 // We must relocate the System::_well_known_klasses only after we have copied the
1268 // java objects in during dump_java_heap_objects(): during the object copy, we operate on
1269 // old objects which assert that their klass is the original klass.
1270 static void relocate_well_known_klasses() {
1271 {
1272 tty->print_cr("Relocating SystemDictionary::_well_known_klasses[] ... ");
1273 ResourceMark rm;
1274 RefRelocator ext_reloc;
1275 SystemDictionary::well_known_klasses_do(&ext_reloc);
1276 }
1277 // NOTE: after this point, we shouldn't have any globals that can reach the old
1278 // objects.
1279
1280 // We cannot use any of the objects in the heap anymore (except for the objects
1281 // in the CDS shared string regions) because their headers no longer point to
1282 // valid Klasses.
1283 }
1284
1285 static void iterate_roots(MetaspaceClosure* it) {
1286 GrowableArray<Symbol*>* symbols = _ssc->get_sorted_symbols();
1287 for (int i=0; i<symbols->length(); i++) {
1288 it->push(symbols->adr_at(i));
1289 }
1290 if (_global_klass_objects != NULL) {
1291 // Need to fix up the pointers
1292 for (int i = 0; i < _global_klass_objects->length(); i++) {
1293 // NOTE -- this requires that the vtable is NOT yet patched, or else we are hosed.
1294 it->push(_global_klass_objects->adr_at(i));
1295 }
1296 }
1297 FileMapInfo::metaspace_pointers_do(it);
1298 SystemDictionary::classes_do(it);
1299 Universe::metaspace_pointers_do(it);
1300 SymbolTable::metaspace_pointers_do(it);
1301 vmSymbols::metaspace_pointers_do(it);
1302 }
1303
1304 static Klass* get_relocated_klass(Klass* orig_klass) {
1305 assert(DumpSharedSpaces, "dump time only");
1306 address* pp = _new_loc_table->get((address)orig_klass);
1307 assert(pp != NULL, "must be");
1308 Klass* klass = (Klass*)(*pp);
1309 assert(klass->is_klass(), "must be");
1310 return klass;
1311 }
1312 };
1313
1314 DumpAllocStats* ArchiveCompactor::_alloc_stats;
1315 SortedSymbolClosure* ArchiveCompactor::_ssc;
1316 ArchiveCompactor::RelocationTable* ArchiveCompactor::_new_loc_table;
1317
1318 void VM_PopulateDumpSharedSpace::write_region(FileMapInfo* mapinfo, int region_idx,
1319 DumpRegion* dump_region, bool read_only, bool allow_exec) {
1320 mapinfo->write_region(region_idx, dump_region->base(), dump_region->used(), read_only, allow_exec);
1321 }
1322
1323 void VM_PopulateDumpSharedSpace::dump_symbols() {
1324 tty->print_cr("Dumping symbol table ...");
1325
1326 NOT_PRODUCT(SymbolTable::verify());
1327 SymbolTable::write_to_archive();
1328 }
1329
1330 char* VM_PopulateDumpSharedSpace::dump_read_only_tables() {
1331 char* oldtop = _ro_region.top();
1332 // Reorder the system dictionary. Moving the symbols affects
1333 // how the hash table indices are calculated.
1334 SystemDictionary::reorder_dictionary_for_sharing();
1335
1336 tty->print("Removing java_mirror ... ");
1337 if (!MetaspaceShared::is_heap_object_archiving_allowed()) {
1338 clear_basic_type_mirrors();
1339 }
1340 remove_java_mirror_in_classes();
1341 tty->print_cr("done. ");
1342 NOT_PRODUCT(SystemDictionary::verify();)
1343
1344 size_t buckets_bytes = SystemDictionary::count_bytes_for_buckets();
1345 char* buckets_top = _ro_region.allocate(buckets_bytes, sizeof(intptr_t));
1346 SystemDictionary::copy_buckets(buckets_top, _ro_region.top());
1347
1348 size_t table_bytes = SystemDictionary::count_bytes_for_table();
1349 char* table_top = _ro_region.allocate(table_bytes, sizeof(intptr_t));
1350 SystemDictionary::copy_table(table_top, _ro_region.top());
1351
1352 // Write the other data to the output array.
1353 WriteClosure wc(&_ro_region);
1354 MetaspaceShared::serialize(&wc);
1355
1356 char* newtop = _ro_region.top();
1357 ArchiveCompactor::alloc_stats()->record_other_type(int(newtop - oldtop), true);
1358 return buckets_top;
1359 }
1360
1361 void VM_PopulateDumpSharedSpace::doit() {
1362 Thread* THREAD = VMThread::vm_thread();
1363
1364 FileMapInfo::check_nonempty_dir_in_shared_path_table();
1365
1366 NOT_PRODUCT(SystemDictionary::verify();)
1367 // The following guarantee is meant to ensure that no loader constraints
1368 // exist yet, since the constraints table is not shared. This becomes
1369 // more important now that we don't re-initialize vtables/itables for
1370 // shared classes at runtime, where constraints were previously created.
1371 guarantee(SystemDictionary::constraints()->number_of_entries() == 0,
1372 "loader constraints are not saved");
1373 guarantee(SystemDictionary::placeholders()->number_of_entries() == 0,
1374 "placeholders are not saved");
1375 // Revisit and implement this if we prelink method handle call sites:
1376 guarantee(SystemDictionary::invoke_method_table() == NULL ||
1377 SystemDictionary::invoke_method_table()->number_of_entries() == 0,
1378 "invoke method table is not saved");
1379
1380 // At this point, many classes have been loaded.
1381 // Gather systemDictionary classes in a global array and do everything to
1382 // that so we don't have to walk the SystemDictionary again.
1383 _global_klass_objects = new GrowableArray<Klass*>(1000);
1384 CollectClassesClosure collect_classes;
1385 ClassLoaderDataGraph::loaded_classes_do(&collect_classes);
1386
1387 tty->print_cr("Number of classes %d", _global_klass_objects->length());
1388 {
1389 int num_type_array = 0, num_obj_array = 0, num_inst = 0;
1390 for (int i = 0; i < _global_klass_objects->length(); i++) {
1391 Klass* k = _global_klass_objects->at(i);
1392 if (k->is_instance_klass()) {
1393 num_inst ++;
1394 } else if (k->is_objArray_klass()) {
1395 num_obj_array ++;
1396 } else {
1397 assert(k->is_typeArray_klass(), "sanity");
1398 num_type_array ++;
1399 }
1400 }
1401 tty->print_cr(" instance classes = %5d", num_inst);
1402 tty->print_cr(" obj array classes = %5d", num_obj_array);
1403 tty->print_cr(" type array classes = %5d", num_type_array);
1404 }
1405
1406 // Ensure the ConstMethods won't be modified at run-time
1407 tty->print("Updating ConstMethods ... ");
1408 rewrite_nofast_bytecodes_and_calculate_fingerprints();
1409 tty->print_cr("done. ");
1410
1411 // Move classes from platform/system dictionaries into the boot dictionary
1412 SystemDictionary::combine_shared_dictionaries();
1413
1414 // Make sure all classes have a correct loader type.
1415 ClassLoaderData::the_null_class_loader_data()->dictionary()->classes_do(MetaspaceShared::check_shared_class_loader_type);
1416
1417 // Remove all references outside the metadata
1418 tty->print("Removing unshareable information ... ");
1419 remove_unshareable_in_classes();
1420 tty->print_cr("done. ");
1421
1422 // We don't support archiving anonymous classes. Verify that they are not stored in
1423 // the any dictionaries.
1424 NOT_PRODUCT(assert_no_anonymoys_classes_in_dictionaries());
1425
1426 SystemDictionaryShared::finalize_verification_constraints();
1427
1428 ArchiveCompactor::initialize();
1429 ArchiveCompactor::copy_and_compact();
1430
1431 dump_symbols();
1432
1433 // Dump supported java heap objects
1434 _closed_archive_heap_regions = NULL;
1435 _open_archive_heap_regions = NULL;
1436 dump_java_heap_objects();
1437
1438 ArchiveCompactor::relocate_well_known_klasses();
1439
1440 char* read_only_tables_start = dump_read_only_tables();
1441 _ro_region.pack(&_md_region);
1442
1443 char* vtbl_list = _md_region.top();
1444 MetaspaceShared::allocate_cpp_vtable_clones();
1445 _md_region.pack(&_od_region);
1446
1447 // Relocate the archived class file data into the od region
1448 relocate_cached_class_file();
1449 _od_region.pack();
1450
1451 // The 5 core spaces are allocated consecutively mc->rw->ro->md->od, so there total size
1452 // is just the spaces between the two ends.
1453 size_t core_spaces_size = _od_region.end() - _mc_region.base();
1454 assert(core_spaces_size == (size_t)align_up(core_spaces_size, Metaspace::reserve_alignment()),
1455 "should already be aligned");
1456
1457 // During patching, some virtual methods may be called, so at this point
1458 // the vtables must contain valid methods (as filled in by CppVtableCloner::allocate).
1459 MetaspaceShared::patch_cpp_vtable_pointers();
1460
1461 // The vtable clones contain addresses of the current process.
1462 // We don't want to write these addresses into the archive.
1463 MetaspaceShared::zero_cpp_vtable_clones_for_writing();
1464
1465 // Create and write the archive file that maps the shared spaces.
1466
1467 FileMapInfo* mapinfo = new FileMapInfo();
1468 mapinfo->populate_header(os::vm_allocation_granularity());
1469 mapinfo->set_read_only_tables_start(read_only_tables_start);
1470 mapinfo->set_misc_data_patching_start(vtbl_list);
1471 mapinfo->set_cds_i2i_entry_code_buffers(MetaspaceShared::cds_i2i_entry_code_buffers());
1472 mapinfo->set_cds_i2i_entry_code_buffers_size(MetaspaceShared::cds_i2i_entry_code_buffers_size());
1473 mapinfo->set_core_spaces_size(core_spaces_size);
1474
1475 for (int pass=1; pass<=2; pass++) {
1476 if (pass == 1) {
1477 // The first pass doesn't actually write the data to disk. All it
1478 // does is to update the fields in the mapinfo->_header.
1479 } else {
1480 // After the first pass, the contents of mapinfo->_header are finalized,
1481 // so we can compute the header's CRC, and write the contents of the header
1482 // and the regions into disk.
1483 mapinfo->open_for_write();
1484 mapinfo->set_header_crc(mapinfo->compute_header_crc());
1485 }
1486 mapinfo->write_header();
1487
1488 // NOTE: md contains the trampoline code for method entries, which are patched at run time,
1489 // so it needs to be read/write.
1490 write_region(mapinfo, MetaspaceShared::mc, &_mc_region, /*read_only=*/false,/*allow_exec=*/true);
1491 write_region(mapinfo, MetaspaceShared::rw, &_rw_region, /*read_only=*/false,/*allow_exec=*/false);
1492 write_region(mapinfo, MetaspaceShared::ro, &_ro_region, /*read_only=*/true, /*allow_exec=*/false);
1493 write_region(mapinfo, MetaspaceShared::md, &_md_region, /*read_only=*/false,/*allow_exec=*/false);
1494 write_region(mapinfo, MetaspaceShared::od, &_od_region, /*read_only=*/true, /*allow_exec=*/false);
1495
1496 _total_string_region_size = mapinfo->write_archive_heap_regions(
1497 _closed_archive_heap_regions,
1498 MetaspaceShared::first_string,
1499 MetaspaceShared::max_strings);
1500 _total_open_archive_region_size = mapinfo->write_archive_heap_regions(
1501 _open_archive_heap_regions,
1502 MetaspaceShared::first_open_archive_heap_region,
1503 MetaspaceShared::max_open_archive_heap_region);
1504 }
1505
1506 mapinfo->close();
1507
1508 // Restore the vtable in case we invoke any virtual methods.
1509 MetaspaceShared::clone_cpp_vtables((intptr_t*)vtbl_list);
1510
1511 print_region_stats();
1512
1513 if (log_is_enabled(Info, cds)) {
1514 ArchiveCompactor::alloc_stats()->print_stats(int(_ro_region.used()), int(_rw_region.used()),
1515 int(_mc_region.used()), int(_md_region.used()));
1516 }
1517
1518 if (PrintSystemDictionaryAtExit) {
1519 SystemDictionary::print();
1520 }
1521 // There may be other pending VM operations that operate on the InstanceKlasses,
1522 // which will fail because InstanceKlasses::remove_unshareable_info()
1523 // has been called. Forget these operations and exit the VM directly.
1524 vm_direct_exit(0);
1525 }
1526
1527 void VM_PopulateDumpSharedSpace::print_region_stats() {
1528 // Print statistics of all the regions
1529 const size_t total_reserved = _ro_region.reserved() + _rw_region.reserved() +
1530 _mc_region.reserved() + _md_region.reserved() +
1531 _od_region.reserved() +
1532 _total_string_region_size +
1533 _total_open_archive_region_size;
1534 const size_t total_bytes = _ro_region.used() + _rw_region.used() +
1535 _mc_region.used() + _md_region.used() +
1536 _od_region.used() +
1537 _total_string_region_size +
1538 _total_open_archive_region_size;
1539 const double total_u_perc = percent_of(total_bytes, total_reserved);
1540
1541 _mc_region.print(total_reserved);
1542 _rw_region.print(total_reserved);
1543 _ro_region.print(total_reserved);
1544 _md_region.print(total_reserved);
1545 _od_region.print(total_reserved);
1546 print_heap_region_stats(_closed_archive_heap_regions, "st", total_reserved);
1547 print_heap_region_stats(_open_archive_heap_regions, "oa", total_reserved);
1548
1549 tty->print_cr("total : " SIZE_FORMAT_W(9) " [100.0%% of total] out of " SIZE_FORMAT_W(9) " bytes [%5.1f%% used]",
1550 total_bytes, total_reserved, total_u_perc);
1551 }
1552
1553 void VM_PopulateDumpSharedSpace::print_heap_region_stats(GrowableArray<MemRegion> *heap_mem,
1554 const char *name, const size_t total_size) {
1555 int arr_len = heap_mem == NULL ? 0 : heap_mem->length();
1556 for (int i = 0; i < arr_len; i++) {
1557 char* start = (char*)heap_mem->at(i).start();
1558 size_t size = heap_mem->at(i).byte_size();
1559 char* top = start + size;
1560 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,
1561 name, i, size, size/double(total_size)*100.0, size, p2i(start));
1562
1563 }
1564 }
1565
1566 // Update a Java object to point its Klass* to the new location after
1567 // shared archive has been compacted.
1568 void MetaspaceShared::relocate_klass_ptr(oop o) {
1569 assert(DumpSharedSpaces, "sanity");
1570 Klass* k = ArchiveCompactor::get_relocated_klass(o->klass());
1571 o->set_klass(k);
1572 }
1573
1574 Klass* MetaspaceShared::get_relocated_klass(Klass *k) {
1575 assert(DumpSharedSpaces, "sanity");
1576 return ArchiveCompactor::get_relocated_klass(k);
1577 }
1578
1579 class LinkSharedClassesClosure : public KlassClosure {
1580 Thread* THREAD;
1581 bool _made_progress;
1582 public:
1583 LinkSharedClassesClosure(Thread* thread) : THREAD(thread), _made_progress(false) {}
1584
1585 void reset() { _made_progress = false; }
1586 bool made_progress() const { return _made_progress; }
1587
1588 void do_klass(Klass* k) {
1589 if (k->is_instance_klass()) {
1590 InstanceKlass* ik = InstanceKlass::cast(k);
1591 // Link the class to cause the bytecodes to be rewritten and the
1592 // cpcache to be created. Class verification is done according
1593 // to -Xverify setting.
1594 _made_progress |= MetaspaceShared::try_link_class(ik, THREAD);
1595 guarantee(!HAS_PENDING_EXCEPTION, "exception in link_class");
1596
1597 ik->constants()->resolve_class_constants(THREAD);
1598 }
1599 }
1600 };
1601
1602 class CheckSharedClassesClosure : public KlassClosure {
1603 bool _made_progress;
1604 public:
1605 CheckSharedClassesClosure() : _made_progress(false) {}
1606
1607 void reset() { _made_progress = false; }
1608 bool made_progress() const { return _made_progress; }
1609 void do_klass(Klass* k) {
1610 if (k->is_instance_klass() && InstanceKlass::cast(k)->check_sharing_error_state()) {
1611 _made_progress = true;
1612 }
1613 }
1614 };
1615
1616 void MetaspaceShared::check_shared_class_loader_type(InstanceKlass* ik) {
1617 ResourceMark rm;
1618 if (ik->shared_classpath_index() == UNREGISTERED_INDEX) {
1619 guarantee(ik->loader_type() == 0,
1620 "Class loader type must not be set for this class %s", ik->name()->as_C_string());
1621 } else {
1622 guarantee(ik->loader_type() != 0,
1623 "Class loader type must be set for this class %s", ik->name()->as_C_string());
1624 }
1625 }
1626
1627 void MetaspaceShared::link_and_cleanup_shared_classes(TRAPS) {
1628 // We need to iterate because verification may cause additional classes
1629 // to be loaded.
1630 LinkSharedClassesClosure link_closure(THREAD);
1631 do {
1632 link_closure.reset();
1633 ClassLoaderDataGraph::loaded_classes_do(&link_closure);
1634 guarantee(!HAS_PENDING_EXCEPTION, "exception in link_class");
1635 } while (link_closure.made_progress());
1636
1637 if (_has_error_classes) {
1638 // Mark all classes whose super class or interfaces failed verification.
1639 CheckSharedClassesClosure check_closure;
1640 do {
1641 // Not completely sure if we need to do this iteratively. Anyway,
1642 // we should come here only if there are unverifiable classes, which
1643 // shouldn't happen in normal cases. So better safe than sorry.
1644 check_closure.reset();
1645 ClassLoaderDataGraph::loaded_classes_do(&check_closure);
1646 } while (check_closure.made_progress());
1647
1648 if (IgnoreUnverifiableClassesDuringDump) {
1649 // This is useful when running JCK or SQE tests. You should not
1650 // enable this when running real apps.
1651 SystemDictionary::remove_classes_in_error_state();
1652 } else {
1653 tty->print_cr("Please remove the unverifiable classes from your class list and try again");
1654 exit(1);
1655 }
1656 }
1657 }
1658
1659 void MetaspaceShared::prepare_for_dumping() {
1660 Arguments::check_unsupported_dumping_properties();
1661 ClassLoader::initialize_shared_path();
1662 }
1663
1664 // Preload classes from a list, populate the shared spaces and dump to a
1665 // file.
1666 void MetaspaceShared::preload_and_dump(TRAPS) {
1667 { TraceTime timer("Dump Shared Spaces", TRACETIME_LOG(Info, startuptime));
1668 ResourceMark rm;
1669 char class_list_path_str[JVM_MAXPATHLEN];
1670 // Preload classes to be shared.
1671 // Should use some os:: method rather than fopen() here. aB.
1672 const char* class_list_path;
1673 if (SharedClassListFile == NULL) {
1674 // Construct the path to the class list (in jre/lib)
1675 // Walk up two directories from the location of the VM and
1676 // optionally tack on "lib" (depending on platform)
1677 os::jvm_path(class_list_path_str, sizeof(class_list_path_str));
1678 for (int i = 0; i < 3; i++) {
1679 char *end = strrchr(class_list_path_str, *os::file_separator());
1680 if (end != NULL) *end = '\0';
1681 }
1682 int class_list_path_len = (int)strlen(class_list_path_str);
1683 if (class_list_path_len >= 3) {
1684 if (strcmp(class_list_path_str + class_list_path_len - 3, "lib") != 0) {
1685 if (class_list_path_len < JVM_MAXPATHLEN - 4) {
1686 jio_snprintf(class_list_path_str + class_list_path_len,
1687 sizeof(class_list_path_str) - class_list_path_len,
1688 "%slib", os::file_separator());
1689 class_list_path_len += 4;
1690 }
1691 }
1692 }
1693 if (class_list_path_len < JVM_MAXPATHLEN - 10) {
1694 jio_snprintf(class_list_path_str + class_list_path_len,
1695 sizeof(class_list_path_str) - class_list_path_len,
1696 "%sclasslist", os::file_separator());
1697 }
1698 class_list_path = class_list_path_str;
1699 } else {
1700 class_list_path = SharedClassListFile;
1701 }
1702
1703 tty->print_cr("Loading classes to share ...");
1704 _has_error_classes = false;
1705 int class_count = preload_classes(class_list_path, THREAD);
1706 if (ExtraSharedClassListFile) {
1707 class_count += preload_classes(ExtraSharedClassListFile, THREAD);
1708 }
1709 tty->print_cr("Loading classes to share: done.");
1710
1711 log_info(cds)("Shared spaces: preloaded %d classes", class_count);
1712
1713 // Rewrite and link classes
1714 tty->print_cr("Rewriting and linking classes ...");
1715
1716 // Link any classes which got missed. This would happen if we have loaded classes that
1717 // were not explicitly specified in the classlist. E.g., if an interface implemented by class K
1718 // fails verification, all other interfaces that were not specified in the classlist but
1719 // are implemented by K are not verified.
1720 link_and_cleanup_shared_classes(CATCH);
1721 tty->print_cr("Rewriting and linking classes: done");
1722
1723 SystemDictionary::clear_invoke_method_table();
1724
1725 VM_PopulateDumpSharedSpace op;
1726 VMThread::execute(&op);
1727 }
1728 }
1729
1730
1731 int MetaspaceShared::preload_classes(const char* class_list_path, TRAPS) {
1732 ClassListParser parser(class_list_path);
1733 int class_count = 0;
1734
1735 while (parser.parse_one_line()) {
1736 Klass* klass = ClassLoaderExt::load_one_class(&parser, THREAD);
1737 if (HAS_PENDING_EXCEPTION) {
1738 if (klass == NULL &&
1739 (PENDING_EXCEPTION->klass()->name() == vmSymbols::java_lang_ClassNotFoundException())) {
1740 // print a warning only when the pending exception is class not found
1741 tty->print_cr("Preload Warning: Cannot find %s", parser.current_class_name());
1742 }
1743 CLEAR_PENDING_EXCEPTION;
1744 }
1745 if (klass != NULL) {
1746 if (log_is_enabled(Trace, cds)) {
1747 ResourceMark rm;
1748 log_trace(cds)("Shared spaces preloaded: %s", klass->external_name());
1749 }
1750
1751 if (klass->is_instance_klass()) {
1752 InstanceKlass* ik = InstanceKlass::cast(klass);
1753
1754 // Link the class to cause the bytecodes to be rewritten and the
1755 // cpcache to be created. The linking is done as soon as classes
1756 // are loaded in order that the related data structures (klass and
1757 // cpCache) are located together.
1758 try_link_class(ik, THREAD);
1759 guarantee(!HAS_PENDING_EXCEPTION, "exception in link_class");
1760 }
1761
1762 class_count++;
1763 }
1764 }
1765
1766 return class_count;
1767 }
1768
1769 // Returns true if the class's status has changed
1770 bool MetaspaceShared::try_link_class(InstanceKlass* ik, TRAPS) {
1771 assert(DumpSharedSpaces, "should only be called during dumping");
1772 if (ik->init_state() < InstanceKlass::linked) {
1773 bool saved = BytecodeVerificationLocal;
1774 if (ik->loader_type() == 0 && ik->class_loader() == NULL) {
1775 // The verification decision is based on BytecodeVerificationRemote
1776 // for non-system classes. Since we are using the NULL classloader
1777 // to load non-system classes for customized class loaders during dumping,
1778 // we need to temporarily change BytecodeVerificationLocal to be the same as
1779 // BytecodeVerificationRemote. Note this can cause the parent system
1780 // classes also being verified. The extra overhead is acceptable during
1781 // dumping.
1782 BytecodeVerificationLocal = BytecodeVerificationRemote;
1783 }
1784 ik->link_class(THREAD);
1785 if (HAS_PENDING_EXCEPTION) {
1786 ResourceMark rm;
1787 tty->print_cr("Preload Warning: Verification failed for %s",
1788 ik->external_name());
1789 CLEAR_PENDING_EXCEPTION;
1790 ik->set_in_error_state();
1791 _has_error_classes = true;
1792 }
1793 BytecodeVerificationLocal = saved;
1794 return true;
1795 } else {
1796 return false;
1797 }
1798 }
1799
1800 #if INCLUDE_CDS_JAVA_HEAP
1801 void VM_PopulateDumpSharedSpace::dump_java_heap_objects() {
1802 if (!MetaspaceShared::is_heap_object_archiving_allowed()) {
1803 if (log_is_enabled(Info, cds)) {
1804 log_info(cds)(
1805 "Archived java heap is not supported as UseG1GC, "
1806 "UseCompressedOops and UseCompressedClassPointers are required."
1807 "Current settings: UseG1GC=%s, UseCompressedOops=%s, UseCompressedClassPointers=%s.",
1808 BOOL_TO_STR(UseG1GC), BOOL_TO_STR(UseCompressedOops),
1809 BOOL_TO_STR(UseCompressedClassPointers));
1810 }
1811 return;
1812 }
1813
1814 {
1815 NoSafepointVerifier nsv;
1816
1817 // Cache for recording where the archived objects are copied to
1818 MetaspaceShared::create_archive_object_cache();
1819
1820 tty->print_cr("Dumping objects to closed archive heap region ...");
1821 NOT_PRODUCT(StringTable::verify());
1822 // The closed space has maximum two regions. See FileMapInfo::write_archive_heap_regions() for details.
1823 _closed_archive_heap_regions = new GrowableArray<MemRegion>(2);
1824 MetaspaceShared::dump_closed_archive_heap_objects(_closed_archive_heap_regions);
1825
1826 tty->print_cr("Dumping objects to open archive heap region ...");
1827 _open_archive_heap_regions = new GrowableArray<MemRegion>(2);
1828 MetaspaceShared::dump_open_archive_heap_objects(_open_archive_heap_regions);
1829
1830 MetaspaceShared::destroy_archive_object_cache();
1831 }
1832
1833 G1HeapVerifier::verify_archive_regions();
1834 }
1835
1836 void MetaspaceShared::dump_closed_archive_heap_objects(
1837 GrowableArray<MemRegion> * closed_archive) {
1838 assert(is_heap_object_archiving_allowed(), "Cannot dump java heap objects");
1839
1840 Thread* THREAD = Thread::current();
1841 G1CollectedHeap::heap()->begin_archive_alloc_range();
1842
1843 // Archive interned string objects
1844 StringTable::write_to_archive();
1845
1846 G1CollectedHeap::heap()->end_archive_alloc_range(closed_archive,
1847 os::vm_allocation_granularity());
1848 }
1849
1850 void MetaspaceShared::dump_open_archive_heap_objects(
1851 GrowableArray<MemRegion> * open_archive) {
1852 assert(UseG1GC, "Only support G1 GC");
1853 assert(UseCompressedOops && UseCompressedClassPointers,
1854 "Only support UseCompressedOops and UseCompressedClassPointers enabled");
1855
1856 Thread* THREAD = Thread::current();
1857 G1CollectedHeap::heap()->begin_archive_alloc_range(true /* open */);
1858
1859 java_lang_Class::archive_basic_type_mirrors(THREAD);
1860
1861 MetaspaceShared::archive_klass_objects(THREAD);
1862
1863 G1CollectedHeap::heap()->end_archive_alloc_range(open_archive,
1864 os::vm_allocation_granularity());
1865 }
1866
1867 unsigned MetaspaceShared::obj_hash(oop const& p) {
1868 assert(!p->mark()->has_bias_pattern(),
1869 "this object should never have been locked"); // so identity_hash won't safepoin
1870 unsigned hash = (unsigned)p->identity_hash();
1871 return hash;
1872 }
1873
1874 MetaspaceShared::ArchivedObjectCache* MetaspaceShared::_archive_object_cache = NULL;
1875 oop MetaspaceShared::find_archived_heap_object(oop obj) {
1876 assert(DumpSharedSpaces, "dump-time only");
1877 ArchivedObjectCache* cache = MetaspaceShared::archive_object_cache();
1878 oop* p = cache->get(obj);
1879 if (p != NULL) {
1880 return *p;
1881 } else {
1882 return NULL;
1883 }
1884 }
1885
1886 oop MetaspaceShared::archive_heap_object(oop obj, Thread* THREAD) {
1887 assert(DumpSharedSpaces, "dump-time only");
1888
1889 oop ao = find_archived_heap_object(obj);
1890 if (ao != NULL) {
1891 // already archived
1892 return ao;
1893 }
1894
1895 int len = obj->size();
1896 if (G1CollectedHeap::heap()->is_archive_alloc_too_large(len)) {
1897 return NULL;
1898 }
1899
1900 int hash = obj->identity_hash();
1901 oop archived_oop = (oop)G1CollectedHeap::heap()->archive_mem_allocate(len);
1902 if (archived_oop != NULL) {
1903 Copy::aligned_disjoint_words((HeapWord*)obj, (HeapWord*)archived_oop, len);
1904 relocate_klass_ptr(archived_oop);
1905 ArchivedObjectCache* cache = MetaspaceShared::archive_object_cache();
1906 cache->put(obj, archived_oop);
1907 }
1908 log_debug(cds)("Archived heap object " PTR_FORMAT " ==> " PTR_FORMAT,
1909 p2i(obj), p2i(archived_oop));
1910 return archived_oop;
1911 }
1912
1913 void MetaspaceShared::archive_klass_objects(Thread* THREAD) {
1914 int i;
1915 for (i = 0; i < _global_klass_objects->length(); i++) {
1916 Klass* k = _global_klass_objects->at(i);
1917
1918 // archive mirror object
1919 java_lang_Class::archive_mirror(k, CHECK);
1920
1921 // archive the resolved_referenes array
1922 if (k->is_instance_klass()) {
1923 InstanceKlass* ik = InstanceKlass::cast(k);
1924 ik->constants()->archive_resolved_references(THREAD);
1925 }
1926 }
1927 }
1928
1929 bool MetaspaceShared::is_archive_object(oop p) {
1930 return (p == NULL) ? false : G1ArchiveAllocator::is_archive_object(p);
1931 }
1932
1933 void MetaspaceShared::fixup_mapped_heap_regions() {
1934 FileMapInfo *mapinfo = FileMapInfo::current_info();
1935 mapinfo->fixup_mapped_heap_regions();
1936 }
1937 #endif // INCLUDE_CDS_JAVA_HEAP
1938
1939 // Closure for serializing initialization data in from a data area
1940 // (ptr_array) read from the shared file.
1941
1942 class ReadClosure : public SerializeClosure {
1943 private:
1944 intptr_t** _ptr_array;
1945
1946 inline intptr_t nextPtr() {
1947 return *(*_ptr_array)++;
1948 }
1949
1950 public:
1951 ReadClosure(intptr_t** ptr_array) { _ptr_array = ptr_array; }
1952
1953 void do_ptr(void** p) {
1954 assert(*p == NULL, "initializing previous initialized pointer.");
1955 intptr_t obj = nextPtr();
1956 assert((intptr_t)obj >= 0 || (intptr_t)obj < -100,
1957 "hit tag while initializing ptrs.");
1958 *p = (void*)obj;
1959 }
1960
1961 void do_u4(u4* p) {
1962 intptr_t obj = nextPtr();
1963 *p = (u4)(uintx(obj));
1964 }
1965
1966 void do_tag(int tag) {
1967 int old_tag;
1968 old_tag = (int)(intptr_t)nextPtr();
1969 // do_int(&old_tag);
1970 assert(tag == old_tag, "old tag doesn't match");
1971 FileMapInfo::assert_mark(tag == old_tag);
1972 }
1973
1974 void do_oop(oop *p) {
1975 narrowOop o = (narrowOop)nextPtr();
1976 if (o == 0 || !MetaspaceShared::open_archive_heap_region_mapped()) {
1977 p = NULL;
1978 } else {
1979 assert(MetaspaceShared::is_heap_object_archiving_allowed(),
1980 "Archived heap object is not allowed");
1981 assert(MetaspaceShared::open_archive_heap_region_mapped(),
1982 "Open archive heap region is not mapped");
1983 RootAccess<IN_ARCHIVE_ROOT>::oop_store(p, CompressedOops::decode_not_null(o));
1984 }
1985 }
1986
1987 void do_region(u_char* start, size_t size) {
1988 assert((intptr_t)start % sizeof(intptr_t) == 0, "bad alignment");
1989 assert(size % sizeof(intptr_t) == 0, "bad size");
1990 do_tag((int)size);
1991 while (size > 0) {
1992 *(intptr_t*)start = nextPtr();
1993 start += sizeof(intptr_t);
1994 size -= sizeof(intptr_t);
1995 }
1996 }
1997
1998 bool reading() const { return true; }
1999 };
2000
2001 // Return true if given address is in the misc data region
2002 bool MetaspaceShared::is_in_shared_region(const void* p, int idx) {
2003 return UseSharedSpaces && FileMapInfo::current_info()->is_in_shared_region(p, idx);
2004 }
2005
2006 bool MetaspaceShared::is_in_trampoline_frame(address addr) {
2007 if (UseSharedSpaces && is_in_shared_region(addr, MetaspaceShared::mc)) {
2008 return true;
2009 }
2010 return false;
2011 }
2012
2013 void MetaspaceShared::print_shared_spaces() {
2014 if (UseSharedSpaces) {
2015 FileMapInfo::current_info()->print_shared_spaces();
2016 }
2017 }
2018
2019
2020 // Map shared spaces at requested addresses and return if succeeded.
2021 bool MetaspaceShared::map_shared_spaces(FileMapInfo* mapinfo) {
2022 size_t image_alignment = mapinfo->alignment();
2023
2024 #ifndef _WINDOWS
2025 // Map in the shared memory and then map the regions on top of it.
2026 // On Windows, don't map the memory here because it will cause the
2027 // mappings of the regions to fail.
2028 ReservedSpace shared_rs = mapinfo->reserve_shared_memory();
2029 if (!shared_rs.is_reserved()) return false;
2030 #endif
2031
2032 assert(!DumpSharedSpaces, "Should not be called with DumpSharedSpaces");
2033
2034 char* ro_base = NULL; char* ro_top;
2035 char* rw_base = NULL; char* rw_top;
2036 char* mc_base = NULL; char* mc_top;
2037 char* md_base = NULL; char* md_top;
2038 char* od_base = NULL; char* od_top;
2039
2040 // Map each shared region
2041 if ((mc_base = mapinfo->map_region(mc, &mc_top)) != NULL &&
2042 (rw_base = mapinfo->map_region(rw, &rw_top)) != NULL &&
2043 (ro_base = mapinfo->map_region(ro, &ro_top)) != NULL &&
2044 (md_base = mapinfo->map_region(md, &md_top)) != NULL &&
2045 (od_base = mapinfo->map_region(od, &od_top)) != NULL &&
2046 (image_alignment == (size_t)os::vm_allocation_granularity()) &&
2047 mapinfo->validate_shared_path_table()) {
2048 // Success -- set up MetaspaceObj::_shared_metaspace_{base,top} for
2049 // fast checking in MetaspaceShared::is_in_shared_metaspace() and
2050 // MetaspaceObj::is_shared().
2051 //
2052 // We require that mc->rw->ro->md->od to be laid out consecutively, with no
2053 // gaps between them. That way, we can ensure that the OS won't be able to
2054 // allocate any new memory spaces inside _shared_metaspace_{base,top}, which
2055 // would mess up the simple comparision in MetaspaceShared::is_in_shared_metaspace().
2056 assert(mc_base < ro_base && mc_base < rw_base && mc_base < md_base && mc_base < od_base, "must be");
2057 assert(od_top > ro_top && od_top > rw_top && od_top > md_top && od_top > mc_top , "must be");
2058 assert(mc_top == rw_base, "must be");
2059 assert(rw_top == ro_base, "must be");
2060 assert(ro_top == md_base, "must be");
2061 assert(md_top == od_base, "must be");
2062
2063 MetaspaceObj::_shared_metaspace_base = (void*)mc_base;
2064 MetaspaceObj::_shared_metaspace_top = (void*)od_top;
2065 return true;
2066 } else {
2067 // If there was a failure in mapping any of the spaces, unmap the ones
2068 // that succeeded
2069 if (ro_base != NULL) mapinfo->unmap_region(ro);
2070 if (rw_base != NULL) mapinfo->unmap_region(rw);
2071 if (mc_base != NULL) mapinfo->unmap_region(mc);
2072 if (md_base != NULL) mapinfo->unmap_region(md);
2073 if (od_base != NULL) mapinfo->unmap_region(od);
2074 #ifndef _WINDOWS
2075 // Release the entire mapped region
2076 shared_rs.release();
2077 #endif
2078 // If -Xshare:on is specified, print out the error message and exit VM,
2079 // otherwise, set UseSharedSpaces to false and continue.
2080 if (RequireSharedSpaces || PrintSharedArchiveAndExit) {
2081 vm_exit_during_initialization("Unable to use shared archive.", "Failed map_region for using -Xshare:on.");
2082 } else {
2083 FLAG_SET_DEFAULT(UseSharedSpaces, false);
2084 }
2085 return false;
2086 }
2087 }
2088
2089 // Read the miscellaneous data from the shared file, and
2090 // serialize it out to its various destinations.
2091
2092 void MetaspaceShared::initialize_shared_spaces() {
2093 FileMapInfo *mapinfo = FileMapInfo::current_info();
2094 _cds_i2i_entry_code_buffers = mapinfo->cds_i2i_entry_code_buffers();
2095 _cds_i2i_entry_code_buffers_size = mapinfo->cds_i2i_entry_code_buffers_size();
2096 _core_spaces_size = mapinfo->core_spaces_size();
2097 char* buffer = mapinfo->misc_data_patching_start();
2098 clone_cpp_vtables((intptr_t*)buffer);
2099
2100 // The rest of the data is now stored in the RW region
2101 buffer = mapinfo->read_only_tables_start();
2102 int sharedDictionaryLen = *(intptr_t*)buffer;
2103 buffer += sizeof(intptr_t);
2104 int number_of_entries = *(intptr_t*)buffer;
2105 buffer += sizeof(intptr_t);
2106 SystemDictionary::set_shared_dictionary((HashtableBucket<mtClass>*)buffer,
2107 sharedDictionaryLen,
2108 number_of_entries);
2109 buffer += sharedDictionaryLen;
2110
2111 // The following data are the linked list elements
2112 // (HashtableEntry objects) for the shared dictionary table.
2113
2114 int len = *(intptr_t*)buffer; // skip over shared dictionary entries
2115 buffer += sizeof(intptr_t);
2116 buffer += len;
2117
2118 // Verify various attributes of the archive, plus initialize the
2119 // shared string/symbol tables
2120 intptr_t* array = (intptr_t*)buffer;
2121 ReadClosure rc(&array);
2122 serialize(&rc);
2123
2124 // Initialize the run-time symbol table.
2125 SymbolTable::create_table();
2126
2127 // Close the mapinfo file
2128 mapinfo->close();
2129
2130 if (PrintSharedArchiveAndExit) {
2131 if (PrintSharedDictionary) {
2132 tty->print_cr("\nShared classes:\n");
2133 SystemDictionary::print_shared(tty);
2134 }
2135 if (_archive_loading_failed) {
2136 tty->print_cr("archive is invalid");
2137 vm_exit(1);
2138 } else {
2139 tty->print_cr("archive is valid");
2140 vm_exit(0);
2141 }
2142 }
2143 }
2144
2145 // JVM/TI RedefineClasses() support:
2146 bool MetaspaceShared::remap_shared_readonly_as_readwrite() {
2147 assert(SafepointSynchronize::is_at_safepoint(), "must be at safepoint");
2148
2149 if (UseSharedSpaces) {
2150 // remap the shared readonly space to shared readwrite, private
2151 FileMapInfo* mapinfo = FileMapInfo::current_info();
2152 if (!mapinfo->remap_shared_readonly_as_readwrite()) {
2153 return false;
2154 }
2155 _remapped_readwrite = true;
2156 }
2157 return true;
2158 }
2159
2160 void MetaspaceShared::report_out_of_space(const char* name, size_t needed_bytes) {
2161 // This is highly unlikely to happen on 64-bits because we have reserved a 4GB space.
2162 // On 32-bit we reserve only 256MB so you could run out of space with 100,000 classes
2163 // or so.
2164 _mc_region.print_out_of_space_msg(name, needed_bytes);
2165 _rw_region.print_out_of_space_msg(name, needed_bytes);
2166 _ro_region.print_out_of_space_msg(name, needed_bytes);
2167 _md_region.print_out_of_space_msg(name, needed_bytes);
2168 _od_region.print_out_of_space_msg(name, needed_bytes);
2169
2170 vm_exit_during_initialization(err_msg("Unable to allocate from '%s' region", name),
2171 "Please reduce the number of shared classes.");
2172 }