1 /*
2 * Copyright (c) 2012, 2018, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 #include "precompiled.hpp"
26 #include "jvm.h"
27 #include "classfile/classListParser.hpp"
28 #include "classfile/classLoaderExt.hpp"
29 #include "classfile/dictionary.hpp"
30 #include "classfile/loaderConstraints.hpp"
31 #include "classfile/placeholders.hpp"
32 #include "classfile/sharedClassUtil.hpp"
33 #include "classfile/symbolTable.hpp"
34 #include "classfile/stringTable.hpp"
35 #include "classfile/systemDictionary.hpp"
36 #include "classfile/systemDictionaryShared.hpp"
37 #include "code/codeCache.hpp"
38 #include "interpreter/bytecodeStream.hpp"
39 #include "interpreter/bytecodes.hpp"
40 #include "logging/log.hpp"
41 #include "logging/logMessage.hpp"
42 #include "memory/filemap.hpp"
43 #include "memory/metaspace.hpp"
44 #include "memory/metaspaceClosure.hpp"
45 #include "memory/metaspaceShared.hpp"
46 #include "memory/resourceArea.hpp"
47 #include "oops/compressedOops.inline.hpp"
48 #include "oops/instanceClassLoaderKlass.hpp"
49 #include "oops/instanceMirrorKlass.hpp"
50 #include "oops/instanceRefKlass.hpp"
51 #include "oops/objArrayKlass.hpp"
52 #include "oops/objArrayOop.hpp"
53 #include "oops/oop.inline.hpp"
54 #include "oops/typeArrayKlass.hpp"
55 #include "prims/jvmtiRedefineClasses.hpp"
56 #include "runtime/handles.inline.hpp"
57 #include "runtime/os.hpp"
58 #include "runtime/safepointVerifiers.hpp"
59 #include "runtime/signature.hpp"
60 #include "runtime/timerTrace.hpp"
61 #include "runtime/vmThread.hpp"
62 #include "runtime/vm_operations.hpp"
63 #include "utilities/align.hpp"
64 #include "utilities/defaultStream.hpp"
65 #include "utilities/hashtable.inline.hpp"
66 #if INCLUDE_ALL_GCS
67 #include "gc/g1/g1Allocator.inline.hpp"
68 #include "gc/g1/g1CollectedHeap.hpp"
69 #endif
70
71 ReservedSpace MetaspaceShared::_shared_rs;
72 VirtualSpace MetaspaceShared::_shared_vs;
73 MetaspaceSharedStats MetaspaceShared::_stats;
74 bool MetaspaceShared::_has_error_classes;
75 bool MetaspaceShared::_archive_loading_failed = false;
76 bool MetaspaceShared::_remapped_readwrite = false;
77 bool MetaspaceShared::_open_archive_heap_region_mapped = false;
78 address MetaspaceShared::_cds_i2i_entry_code_buffers = NULL;
79 size_t MetaspaceShared::_cds_i2i_entry_code_buffers_size = 0;
80 size_t MetaspaceShared::_core_spaces_size = 0;
81
82 // The CDS archive is divided into the following regions:
83 // mc - misc code (the method entry trampolines)
84 // rw - read-write metadata
85 // ro - read-only metadata and read-only tables
86 // md - misc data (the c++ vtables)
87 // od - optional data (original class files)
88 //
89 // s0 - shared strings(closed archive heap space) #0
90 // s1 - shared strings(closed archive heap space) #1 (may be empty)
91 // oa0 - open archive heap space #0
92 // oa1 - open archive heap space #1 (may be empty)
93 //
94 // The mc, rw, ro, md and od regions are linearly allocated, starting from
95 // SharedBaseAddress, in the order of mc->rw->ro->md->od. The size of these 5 regions
96 // are page-aligned, and there's no gap between any consecutive regions.
97 //
98 // These 5 regions are populated in the following steps:
99 // [1] All classes are loaded in MetaspaceShared::preload_classes(). All metadata are
100 // temporarily allocated outside of the shared regions. Only the method entry
101 // trampolines are written into the mc region.
102 // [2] ArchiveCompactor copies RW metadata into the rw region.
103 // [3] ArchiveCompactor copies RO metadata into the ro region.
104 // [4] SymbolTable, StringTable, SystemDictionary, and a few other read-only data
105 // are copied into the ro region as read-only tables.
106 // [5] C++ vtables are copied into the md region.
107 // [6] Original class files are copied into the od region.
108 //
109 // The s0/s1 and oa0/oa1 regions are populated inside MetaspaceShared::dump_java_heap_objects.
110 // Their layout is independent of the other 5 regions.
111
112 class DumpRegion {
113 private:
114 const char* _name;
115 char* _base;
116 char* _top;
117 char* _end;
118 bool _is_packed;
119
120 char* expand_top_to(char* newtop) {
121 assert(is_allocatable(), "must be initialized and not packed");
122 assert(newtop >= _top, "must not grow backwards");
123 if (newtop > _end) {
124 MetaspaceShared::report_out_of_space(_name, newtop - _top);
125 ShouldNotReachHere();
126 }
127 MetaspaceShared::commit_shared_space_to(newtop);
128 _top = newtop;
129 return _top;
130 }
131
132 public:
133 DumpRegion(const char* name) : _name(name), _base(NULL), _top(NULL), _end(NULL), _is_packed(false) {}
134
135 char* allocate(size_t num_bytes, size_t alignment=BytesPerWord) {
136 char* p = (char*)align_up(_top, alignment);
137 char* newtop = p + align_up(num_bytes, alignment);
138 expand_top_to(newtop);
139 memset(p, 0, newtop - p);
140 return p;
141 }
142
143 void append_intptr_t(intptr_t n) {
144 assert(is_aligned(_top, sizeof(intptr_t)), "bad alignment");
145 intptr_t *p = (intptr_t*)_top;
146 char* newtop = _top + sizeof(intptr_t);
147 expand_top_to(newtop);
148 *p = n;
149 }
150
151 char* base() const { return _base; }
152 char* top() const { return _top; }
153 char* end() const { return _end; }
154 size_t reserved() const { return _end - _base; }
155 size_t used() const { return _top - _base; }
156 bool is_packed() const { return _is_packed; }
157 bool is_allocatable() const {
158 return !is_packed() && _base != NULL;
159 }
160
161 void print(size_t total_bytes) const {
162 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,
163 _name, used(), percent_of(used(), total_bytes), reserved(), percent_of(used(), reserved()), p2i(_base));
164 }
165 void print_out_of_space_msg(const char* failing_region, size_t needed_bytes) {
166 tty->print("[%-8s] " PTR_FORMAT " - " PTR_FORMAT " capacity =%9d, allocated =%9d",
167 _name, p2i(_base), p2i(_top), int(_end - _base), int(_top - _base));
168 if (strcmp(_name, failing_region) == 0) {
169 tty->print_cr(" required = %d", int(needed_bytes));
170 } else {
171 tty->cr();
172 }
173 }
174
175 void init(const ReservedSpace* rs) {
176 _base = _top = rs->base();
177 _end = rs->end();
178 }
179 void init(char* b, char* t, char* e) {
180 _base = b;
181 _top = t;
182 _end = e;
183 }
184
185 void pack(DumpRegion* next = NULL) {
186 assert(!is_packed(), "sanity");
187 _end = (char*)align_up(_top, Metaspace::reserve_alignment());
188 _is_packed = true;
189 if (next != NULL) {
190 next->_base = next->_top = this->_end;
191 next->_end = MetaspaceShared::shared_rs()->end();
192 }
193 }
194 bool contains(char* p) {
195 return base() <= p && p < top();
196 }
197 };
198
199
200 DumpRegion _mc_region("mc"), _ro_region("ro"), _rw_region("rw"), _md_region("md"), _od_region("od");
201 size_t _total_string_region_size = 0, _total_open_archive_region_size = 0;
202
203 char* MetaspaceShared::misc_code_space_alloc(size_t num_bytes) {
204 return _mc_region.allocate(num_bytes);
205 }
206
207 char* MetaspaceShared::read_only_space_alloc(size_t num_bytes) {
208 return _ro_region.allocate(num_bytes);
209 }
210
211 void MetaspaceShared::initialize_runtime_shared_and_meta_spaces() {
212 assert(UseSharedSpaces, "Must be called when UseSharedSpaces is enabled");
213
214 // If using shared space, open the file that contains the shared space
215 // and map in the memory before initializing the rest of metaspace (so
216 // the addresses don't conflict)
217 address cds_address = NULL;
218 FileMapInfo* mapinfo = new FileMapInfo();
219
220 // Open the shared archive file, read and validate the header. If
221 // initialization fails, shared spaces [UseSharedSpaces] are
222 // disabled and the file is closed.
223 // Map in spaces now also
224 if (mapinfo->initialize() && map_shared_spaces(mapinfo)) {
225 size_t cds_total = core_spaces_size();
226 cds_address = (address)mapinfo->header()->region_addr(0);
227 #ifdef _LP64
228 if (Metaspace::using_class_space()) {
229 char* cds_end = (char*)(cds_address + cds_total);
230 cds_end = (char *)align_up(cds_end, Metaspace::reserve_alignment());
231 // If UseCompressedClassPointers is set then allocate the metaspace area
232 // above the heap and above the CDS area (if it exists).
233 Metaspace::allocate_metaspace_compressed_klass_ptrs(cds_end, cds_address);
234 // map_heap_regions() compares the current narrow oop and klass encodings
235 // with the archived ones, so it must be done after all encodings are determined.
236 mapinfo->map_heap_regions();
237 }
238 Universe::set_narrow_klass_range(CompressedClassSpaceSize);
239 #endif // _LP64
240 } else {
241 assert(!mapinfo->is_open() && !UseSharedSpaces,
242 "archive file not closed or shared spaces not disabled.");
243 }
244 }
245
246 void MetaspaceShared::initialize_dumptime_shared_and_meta_spaces() {
247 assert(DumpSharedSpaces, "should be called for dump time only");
248 const size_t reserve_alignment = Metaspace::reserve_alignment();
249 bool large_pages = false; // No large pages when dumping the CDS archive.
250 char* shared_base = (char*)align_up((char*)SharedBaseAddress, reserve_alignment);
251
252 #ifdef _LP64
253 // On 64-bit VM, the heap and class space layout will be the same as if
254 // you're running in -Xshare:on mode:
255 //
256 // +-- SharedBaseAddress (default = 0x800000000)
257 // v
258 // +-..---------+---------+ ... +----+----+----+----+----+---------------+
259 // | Heap | Archive | | MC | RW | RO | MD | OD | class space |
260 // +-..---------+---------+ ... +----+----+----+----+----+---------------+
261 // |<-- MaxHeapSize -->| |<-- UnscaledClassSpaceMax = 4GB ------->|
262 //
263 const uint64_t UnscaledClassSpaceMax = (uint64_t(max_juint) + 1);
264 const size_t cds_total = align_down(UnscaledClassSpaceMax, reserve_alignment);
265 #else
266 // We don't support archives larger than 256MB on 32-bit due to limited virtual address space.
267 size_t cds_total = align_down(256*M, reserve_alignment);
268 #endif
269
270 // First try to reserve the space at the specified SharedBaseAddress.
271 _shared_rs = ReservedSpace(cds_total, reserve_alignment, large_pages, shared_base);
272 if (_shared_rs.is_reserved()) {
273 assert(shared_base == 0 || _shared_rs.base() == shared_base, "should match");
274 } else {
275 // Get a mmap region anywhere if the SharedBaseAddress fails.
276 _shared_rs = ReservedSpace(cds_total, reserve_alignment, large_pages);
277 }
278 if (!_shared_rs.is_reserved()) {
279 vm_exit_during_initialization("Unable to reserve memory for shared space",
280 err_msg(SIZE_FORMAT " bytes.", cds_total));
281 }
282
283 #ifdef _LP64
284 // During dump time, we allocate 4GB (UnscaledClassSpaceMax) of space and split it up:
285 // + The upper 1 GB is used as the "temporary compressed class space" -- preload_classes()
286 // will store Klasses into this space.
287 // + The lower 3 GB is used for the archive -- when preload_classes() is done,
288 // ArchiveCompactor will copy the class metadata into this space, first the RW parts,
289 // then the RO parts.
290
291 assert(UseCompressedOops && UseCompressedClassPointers,
292 "UseCompressedOops and UseCompressedClassPointers must be set");
293
294 size_t max_archive_size = align_down(cds_total * 3 / 4, reserve_alignment);
295 ReservedSpace tmp_class_space = _shared_rs.last_part(max_archive_size);
296 CompressedClassSpaceSize = align_down(tmp_class_space.size(), reserve_alignment);
297 _shared_rs = _shared_rs.first_part(max_archive_size);
298
299 // Set up compress class pointers.
300 Universe::set_narrow_klass_base((address)_shared_rs.base());
301 // Set narrow_klass_shift to be LogKlassAlignmentInBytes. This is consistent
302 // with AOT.
303 Universe::set_narrow_klass_shift(LogKlassAlignmentInBytes);
304 // Set the range of klass addresses to 4GB.
305 Universe::set_narrow_klass_range(cds_total);
306
307 Metaspace::initialize_class_space(tmp_class_space);
308 tty->print_cr("narrow_klass_base = " PTR_FORMAT ", narrow_klass_shift = %d",
309 p2i(Universe::narrow_klass_base()), Universe::narrow_klass_shift());
310
311 tty->print_cr("Allocated temporary class space: " SIZE_FORMAT " bytes at " PTR_FORMAT,
312 CompressedClassSpaceSize, p2i(tmp_class_space.base()));
313 #endif
314
315 // Start with 0 committed bytes. The memory will be committed as needed by
316 // MetaspaceShared::commit_shared_space_to().
317 if (!_shared_vs.initialize(_shared_rs, 0)) {
318 vm_exit_during_initialization("Unable to allocate memory for shared space");
319 }
320
321 _mc_region.init(&_shared_rs);
322 tty->print_cr("Allocated shared space: " SIZE_FORMAT " bytes at " PTR_FORMAT,
323 _shared_rs.size(), p2i(_shared_rs.base()));
324 }
325
326 void MetaspaceShared::commit_shared_space_to(char* newtop) {
327 assert(DumpSharedSpaces, "dump-time only");
328 char* base = _shared_rs.base();
329 size_t need_committed_size = newtop - base;
330 size_t has_committed_size = _shared_vs.committed_size();
331 if (need_committed_size < has_committed_size) {
332 return;
333 }
334
335 size_t min_bytes = need_committed_size - has_committed_size;
336 size_t preferred_bytes = 1 * M;
337 size_t uncommitted = _shared_vs.reserved_size() - has_committed_size;
338
339 size_t commit = MAX2(min_bytes, preferred_bytes);
340 assert(commit <= uncommitted, "sanity");
341
342 bool result = _shared_vs.expand_by(commit, false);
343 if (!result) {
344 vm_exit_during_initialization(err_msg("Failed to expand shared space to " SIZE_FORMAT " bytes",
345 need_committed_size));
346 }
347
348 log_info(cds)("Expanding shared spaces by " SIZE_FORMAT_W(7) " bytes [total " SIZE_FORMAT_W(9) " bytes ending at %p]",
349 commit, _shared_vs.actual_committed_size(), _shared_vs.high());
350 }
351
352 // Read/write a data stream for restoring/preserving metadata pointers and
353 // miscellaneous data from/to the shared archive file.
354
355 void MetaspaceShared::serialize(SerializeClosure* soc) {
356 int tag = 0;
357 soc->do_tag(--tag);
358
359 // Verify the sizes of various metadata in the system.
360 soc->do_tag(sizeof(Method));
361 soc->do_tag(sizeof(ConstMethod));
362 soc->do_tag(arrayOopDesc::base_offset_in_bytes(T_BYTE));
363 soc->do_tag(sizeof(ConstantPool));
364 soc->do_tag(sizeof(ConstantPoolCache));
365 soc->do_tag(objArrayOopDesc::base_offset_in_bytes());
366 soc->do_tag(typeArrayOopDesc::base_offset_in_bytes(T_BYTE));
367 soc->do_tag(sizeof(Symbol));
368
369 // Dump/restore miscellaneous metadata.
370 Universe::serialize(soc, true);
371 soc->do_tag(--tag);
372
373 // Dump/restore references to commonly used names and signatures.
374 vmSymbols::serialize(soc);
375 soc->do_tag(--tag);
376
377 // Dump/restore the symbol and string tables
378 SymbolTable::serialize(soc);
379 StringTable::serialize(soc);
380 soc->do_tag(--tag);
381
382 serialize_well_known_classes(soc);
383 soc->do_tag(--tag);
384
385 soc->do_tag(666);
386 }
387
388 void MetaspaceShared::serialize_well_known_classes(SerializeClosure* soc) {
389 java_lang_Class::serialize(soc);
390 java_lang_String::serialize(soc);
391 java_lang_System::serialize(soc);
392 java_lang_ClassLoader::serialize(soc);
393 java_lang_Throwable::serialize(soc);
394 java_lang_Thread::serialize(soc);
395 java_lang_ThreadGroup::serialize(soc);
396 java_lang_AssertionStatusDirectives::serialize(soc);
397 java_lang_ref_SoftReference::serialize(soc);
398 java_lang_invoke_MethodHandle::serialize(soc);
399 java_lang_invoke_DirectMethodHandle::serialize(soc);
400 java_lang_invoke_MemberName::serialize(soc);
401 java_lang_invoke_ResolvedMethodName::serialize(soc);
402 java_lang_invoke_LambdaForm::serialize(soc);
403 java_lang_invoke_MethodType::serialize(soc);
404 java_lang_invoke_CallSite::serialize(soc);
405 java_lang_invoke_MethodHandleNatives_CallSiteContext::serialize(soc);
406 java_security_AccessControlContext::serialize(soc);
407 java_lang_reflect_AccessibleObject::serialize(soc);
408 java_lang_reflect_Method::serialize(soc);
409 java_lang_reflect_Constructor::serialize(soc);
410 java_lang_reflect_Field::serialize(soc);
411 java_nio_Buffer::serialize(soc);
412 reflect_ConstantPool::serialize(soc);
413 reflect_UnsafeStaticFieldAccessorImpl::serialize(soc);
414 java_lang_reflect_Parameter::serialize(soc);
415 java_lang_Module::serialize(soc);
416 java_lang_StackTraceElement::serialize(soc);
417 java_lang_StackFrameInfo::serialize(soc);
418 java_lang_LiveStackFrameInfo::serialize(soc);
419 }
420
421 address MetaspaceShared::cds_i2i_entry_code_buffers(size_t total_size) {
422 if (DumpSharedSpaces) {
423 if (_cds_i2i_entry_code_buffers == NULL) {
424 _cds_i2i_entry_code_buffers = (address)misc_code_space_alloc(total_size);
425 _cds_i2i_entry_code_buffers_size = total_size;
426 }
427 } else if (UseSharedSpaces) {
428 assert(_cds_i2i_entry_code_buffers != NULL, "must already been initialized");
429 } else {
430 return NULL;
431 }
432
433 assert(_cds_i2i_entry_code_buffers_size == total_size, "must not change");
434 return _cds_i2i_entry_code_buffers;
435 }
436
437 // CDS code for dumping shared archive.
438
439 // Global object for holding classes that have been loaded. Since this
440 // is run at a safepoint just before exit, this is the entire set of classes.
441 static GrowableArray<Klass*>* _global_klass_objects;
442
443 static void collect_array_classes(Klass* k) {
444 _global_klass_objects->append_if_missing(k);
445 if (k->is_array_klass()) {
446 // Add in the array classes too
447 ArrayKlass* ak = ArrayKlass::cast(k);
448 Klass* h = ak->higher_dimension();
449 if (h != NULL) {
450 h->array_klasses_do(collect_array_classes);
451 }
452 }
453 }
454
455 class CollectClassesClosure : public KlassClosure {
456 void do_klass(Klass* k) {
457 if (!UseAppCDS && !k->class_loader_data()->is_the_null_class_loader_data()) {
458 // AppCDS is not enabled. Let's omit non-boot classes.
459 return;
460 }
461
462 if (!(k->is_instance_klass() && InstanceKlass::cast(k)->is_in_error_state())) {
463 if (k->is_instance_klass() && InstanceKlass::cast(k)->signers() != NULL) {
464 // Mark any class with signers and don't add to the _global_klass_objects
465 k->set_has_signer_and_not_archived();
466 } else {
467 _global_klass_objects->append_if_missing(k);
468 }
469 }
470 if (k->is_array_klass()) {
471 // Add in the array classes too
472 ArrayKlass* ak = ArrayKlass::cast(k);
473 Klass* h = ak->higher_dimension();
474 if (h != NULL) {
475 h->array_klasses_do(collect_array_classes);
476 }
477 }
478 }
479 };
480
481 static void remove_unshareable_in_classes() {
482 for (int i = 0; i < _global_klass_objects->length(); i++) {
483 Klass* k = _global_klass_objects->at(i);
484 if (!k->is_objArray_klass()) {
485 // InstanceKlass and TypeArrayKlass will in turn call remove_unshareable_info
486 // on their array classes.
487 assert(k->is_instance_klass() || k->is_typeArray_klass(), "must be");
488 k->remove_unshareable_info();
489 }
490 }
491 }
492
493 static void remove_java_mirror_in_classes() {
494 for (int i = 0; i < _global_klass_objects->length(); i++) {
495 Klass* k = _global_klass_objects->at(i);
496 if (!k->is_objArray_klass()) {
497 // InstanceKlass and TypeArrayKlass will in turn call remove_unshareable_info
498 // on their array classes.
499 assert(k->is_instance_klass() || k->is_typeArray_klass(), "must be");
500 k->remove_java_mirror();
501 }
502 }
503 }
504
505 static void clear_basic_type_mirrors() {
506 assert(!MetaspaceShared::is_heap_object_archiving_allowed(), "Sanity");
507 Universe::set_int_mirror(NULL);
508 Universe::set_float_mirror(NULL);
509 Universe::set_double_mirror(NULL);
510 Universe::set_byte_mirror(NULL);
511 Universe::set_bool_mirror(NULL);
512 Universe::set_char_mirror(NULL);
513 Universe::set_long_mirror(NULL);
514 Universe::set_short_mirror(NULL);
515 Universe::set_void_mirror(NULL);
516 }
517
518 static void rewrite_nofast_bytecode(Method* method) {
519 BytecodeStream bcs(method);
520 while (!bcs.is_last_bytecode()) {
521 Bytecodes::Code opcode = bcs.next();
522 switch (opcode) {
523 case Bytecodes::_getfield: *bcs.bcp() = Bytecodes::_nofast_getfield; break;
524 case Bytecodes::_putfield: *bcs.bcp() = Bytecodes::_nofast_putfield; break;
525 case Bytecodes::_aload_0: *bcs.bcp() = Bytecodes::_nofast_aload_0; break;
526 case Bytecodes::_iload: {
527 if (!bcs.is_wide()) {
528 *bcs.bcp() = Bytecodes::_nofast_iload;
529 }
530 break;
531 }
532 default: break;
533 }
534 }
535 }
536
537 // Walk all methods in the class list to ensure that they won't be modified at
538 // run time. This includes:
539 // [1] Rewrite all bytecodes as needed, so that the ConstMethod* will not be modified
540 // at run time by RewriteBytecodes/RewriteFrequentPairs
541 // [2] Assign a fingerprint, so one doesn't need to be assigned at run-time.
542 static void rewrite_nofast_bytecodes_and_calculate_fingerprints() {
543 for (int i = 0; i < _global_klass_objects->length(); i++) {
544 Klass* k = _global_klass_objects->at(i);
545 if (k->is_instance_klass()) {
546 InstanceKlass* ik = InstanceKlass::cast(k);
547 for (int i = 0; i < ik->methods()->length(); i++) {
548 Method* m = ik->methods()->at(i);
549 rewrite_nofast_bytecode(m);
550 Fingerprinter fp(m);
551 // The side effect of this call sets method's fingerprint field.
552 fp.fingerprint();
553 }
554 }
555 }
556 }
557
558 static void relocate_cached_class_file() {
559 for (int i = 0; i < _global_klass_objects->length(); i++) {
560 Klass* k = _global_klass_objects->at(i);
561 if (k->is_instance_klass()) {
562 InstanceKlass* ik = InstanceKlass::cast(k);
563 JvmtiCachedClassFileData* p = ik->get_archived_class_data();
564 if (p != NULL) {
565 int size = offset_of(JvmtiCachedClassFileData, data) + p->length;
566 JvmtiCachedClassFileData* q = (JvmtiCachedClassFileData*)_od_region.allocate(size);
567 q->length = p->length;
568 memcpy(q->data, p->data, p->length);
569 ik->set_archived_class_data(q);
570 }
571 }
572 }
573 }
574
575 NOT_PRODUCT(
576 static void assert_not_anonymous_class(InstanceKlass* k) {
577 assert(!(k->is_anonymous()), "cannot archive anonymous classes");
578 }
579
580 // Anonymous classes are not stored inside any dictionaries. They are created by
581 // SystemDictionary::parse_stream() with a non-null host_klass.
582 static void assert_no_anonymoys_classes_in_dictionaries() {
583 ClassLoaderDataGraph::dictionary_classes_do(assert_not_anonymous_class);
584 })
585
586 // Objects of the Metadata types (such as Klass and ConstantPool) have C++ vtables.
587 // (In GCC this is the field <Type>::_vptr, i.e., first word in the object.)
588 //
589 // Addresses of the vtables and the methods may be different across JVM runs,
590 // if libjvm.so is dynamically loaded at a different base address.
591 //
592 // To ensure that the Metadata objects in the CDS archive always have the correct vtable:
593 //
594 // + at dump time: we redirect the _vptr to point to our own vtables inside
595 // the CDS image
596 // + at run time: we clone the actual contents of the vtables from libjvm.so
597 // into our own tables.
598
599 // Currently, the archive contain ONLY the following types of objects that have C++ vtables.
600 #define CPP_VTABLE_PATCH_TYPES_DO(f) \
601 f(ConstantPool) \
602 f(InstanceKlass) \
603 f(InstanceClassLoaderKlass) \
604 f(InstanceMirrorKlass) \
605 f(InstanceRefKlass) \
606 f(Method) \
607 f(ObjArrayKlass) \
608 f(TypeArrayKlass)
609
610 class CppVtableInfo {
611 intptr_t _vtable_size;
612 intptr_t _cloned_vtable[1];
613 public:
614 static int num_slots(int vtable_size) {
615 return 1 + vtable_size; // Need to add the space occupied by _vtable_size;
616 }
617 int vtable_size() { return int(uintx(_vtable_size)); }
618 void set_vtable_size(int n) { _vtable_size = intptr_t(n); }
619 intptr_t* cloned_vtable() { return &_cloned_vtable[0]; }
620 void zero() { memset(_cloned_vtable, 0, sizeof(intptr_t) * vtable_size()); }
621 // Returns the address of the next CppVtableInfo that can be placed immediately after this CppVtableInfo
622 static size_t byte_size(int vtable_size) {
623 CppVtableInfo i;
624 return pointer_delta(&i._cloned_vtable[vtable_size], &i, sizeof(u1));
625 }
626 };
627
628 template <class T> class CppVtableCloner : public T {
629 static intptr_t* vtable_of(Metadata& m) {
630 return *((intptr_t**)&m);
631 }
632 static CppVtableInfo* _info;
633
634 static int get_vtable_length(const char* name);
635
636 public:
637 // Allocate and initialize the C++ vtable, starting from top, but do not go past end.
638 static intptr_t* allocate(const char* name);
639
640 // Clone the vtable to ...
641 static intptr_t* clone_vtable(const char* name, CppVtableInfo* info);
642
643 static void zero_vtable_clone() {
644 assert(DumpSharedSpaces, "dump-time only");
645 _info->zero();
646 }
647
648 // Switch the vtable pointer to point to the cloned vtable.
649 static void patch(Metadata* obj) {
650 assert(DumpSharedSpaces, "dump-time only");
651 *(void**)obj = (void*)(_info->cloned_vtable());
652 }
653
654 static bool is_valid_shared_object(const T* obj) {
655 intptr_t* vptr = *(intptr_t**)obj;
656 return vptr == _info->cloned_vtable();
657 }
658 };
659
660 template <class T> CppVtableInfo* CppVtableCloner<T>::_info = NULL;
661
662 template <class T>
663 intptr_t* CppVtableCloner<T>::allocate(const char* name) {
664 assert(is_aligned(_md_region.top(), sizeof(intptr_t)), "bad alignment");
665 int n = get_vtable_length(name);
666 _info = (CppVtableInfo*)_md_region.allocate(CppVtableInfo::byte_size(n), sizeof(intptr_t));
667 _info->set_vtable_size(n);
668
669 intptr_t* p = clone_vtable(name, _info);
670 assert((char*)p == _md_region.top(), "must be");
671
672 return p;
673 }
674
675 template <class T>
676 intptr_t* CppVtableCloner<T>::clone_vtable(const char* name, CppVtableInfo* info) {
677 if (!DumpSharedSpaces) {
678 assert(_info == 0, "_info is initialized only at dump time");
679 _info = info; // Remember it -- it will be used by MetaspaceShared::is_valid_shared_method()
680 }
681 T tmp; // Allocate temporary dummy metadata object to get to the original vtable.
682 int n = info->vtable_size();
683 intptr_t* srcvtable = vtable_of(tmp);
684 intptr_t* dstvtable = info->cloned_vtable();
685
686 // We already checked (and, if necessary, adjusted n) when the vtables were allocated, so we are
687 // safe to do memcpy.
688 log_debug(cds, vtables)("Copying %3d vtable entries for %s", n, name);
689 memcpy(dstvtable, srcvtable, sizeof(intptr_t) * n);
690 return dstvtable + n;
691 }
692
693 // To determine the size of the vtable for each type, we use the following
694 // trick by declaring 2 subclasses:
695 //
696 // class CppVtableTesterA: public InstanceKlass {virtual int last_virtual_method() {return 1;} };
697 // class CppVtableTesterB: public InstanceKlass {virtual void* last_virtual_method() {return NULL}; };
698 //
699 // CppVtableTesterA and CppVtableTesterB's vtables have the following properties:
700 // - Their size (N+1) is exactly one more than the size of InstanceKlass's vtable (N)
701 // - The first N entries have are exactly the same as in InstanceKlass's vtable.
702 // - Their last entry is different.
703 //
704 // So to determine the value of N, we just walk CppVtableTesterA and CppVtableTesterB's tables
705 // and find the first entry that's different.
706 //
707 // This works on all C++ compilers supported by Oracle, but you may need to tweak it for more
708 // esoteric compilers.
709
710 template <class T> class CppVtableTesterB: public T {
711 public:
712 virtual int last_virtual_method() {return 1;}
713 };
714
715 template <class T> class CppVtableTesterA : public T {
716 public:
717 virtual void* last_virtual_method() {
718 // Make this different than CppVtableTesterB::last_virtual_method so the C++
719 // compiler/linker won't alias the two functions.
720 return NULL;
721 }
722 };
723
724 template <class T>
725 int CppVtableCloner<T>::get_vtable_length(const char* name) {
726 CppVtableTesterA<T> a;
727 CppVtableTesterB<T> b;
728
729 intptr_t* avtable = vtable_of(a);
730 intptr_t* bvtable = vtable_of(b);
731
732 // Start at slot 1, because slot 0 may be RTTI (on Solaris/Sparc)
733 int vtable_len = 1;
734 for (; ; vtable_len++) {
735 if (avtable[vtable_len] != bvtable[vtable_len]) {
736 break;
737 }
738 }
739 log_debug(cds, vtables)("Found %3d vtable entries for %s", vtable_len, name);
740
741 return vtable_len;
742 }
743
744 #define ALLOC_CPP_VTABLE_CLONE(c) \
745 CppVtableCloner<c>::allocate(#c);
746
747 #define CLONE_CPP_VTABLE(c) \
748 p = CppVtableCloner<c>::clone_vtable(#c, (CppVtableInfo*)p);
749
750 #define ZERO_CPP_VTABLE(c) \
751 CppVtableCloner<c>::zero_vtable_clone();
752
753 // This can be called at both dump time and run time.
754 intptr_t* MetaspaceShared::clone_cpp_vtables(intptr_t* p) {
755 assert(DumpSharedSpaces || UseSharedSpaces, "sanity");
756 CPP_VTABLE_PATCH_TYPES_DO(CLONE_CPP_VTABLE);
757 return p;
758 }
759
760 void MetaspaceShared::zero_cpp_vtable_clones_for_writing() {
761 assert(DumpSharedSpaces, "dump-time only");
762 CPP_VTABLE_PATCH_TYPES_DO(ZERO_CPP_VTABLE);
763 }
764
765 // Allocate and initialize the C++ vtables, starting from top, but do not go past end.
766 void MetaspaceShared::allocate_cpp_vtable_clones() {
767 assert(DumpSharedSpaces, "dump-time only");
768 // Layout (each slot is a intptr_t):
769 // [number of slots in the first vtable = n1]
770 // [ <n1> slots for the first vtable]
771 // [number of slots in the first second = n2]
772 // [ <n2> slots for the second vtable]
773 // ...
774 // The order of the vtables is the same as the CPP_VTAB_PATCH_TYPES_DO macro.
775 CPP_VTABLE_PATCH_TYPES_DO(ALLOC_CPP_VTABLE_CLONE);
776 }
777
778 // Switch the vtable pointer to point to the cloned vtable. We assume the
779 // vtable pointer is in first slot in object.
780 void MetaspaceShared::patch_cpp_vtable_pointers() {
781 int n = _global_klass_objects->length();
782 for (int i = 0; i < n; i++) {
783 Klass* obj = _global_klass_objects->at(i);
784 if (obj->is_instance_klass()) {
785 InstanceKlass* ik = InstanceKlass::cast(obj);
786 if (ik->is_class_loader_instance_klass()) {
787 CppVtableCloner<InstanceClassLoaderKlass>::patch(ik);
788 } else if (ik->is_reference_instance_klass()) {
789 CppVtableCloner<InstanceRefKlass>::patch(ik);
790 } else if (ik->is_mirror_instance_klass()) {
791 CppVtableCloner<InstanceMirrorKlass>::patch(ik);
792 } else {
793 CppVtableCloner<InstanceKlass>::patch(ik);
794 }
795 ConstantPool* cp = ik->constants();
796 CppVtableCloner<ConstantPool>::patch(cp);
797 for (int j = 0; j < ik->methods()->length(); j++) {
798 Method* m = ik->methods()->at(j);
799 CppVtableCloner<Method>::patch(m);
800 assert(CppVtableCloner<Method>::is_valid_shared_object(m), "must be");
801 }
802 } else if (obj->is_objArray_klass()) {
803 CppVtableCloner<ObjArrayKlass>::patch(obj);
804 } else {
805 assert(obj->is_typeArray_klass(), "sanity");
806 CppVtableCloner<TypeArrayKlass>::patch(obj);
807 }
808 }
809 }
810
811 bool MetaspaceShared::is_valid_shared_method(const Method* m) {
812 assert(is_in_shared_metaspace(m), "must be");
813 return CppVtableCloner<Method>::is_valid_shared_object(m);
814 }
815
816 // Closure for serializing initialization data out to a data area to be
817 // written to the shared file.
818
819 class WriteClosure : public SerializeClosure {
820 private:
821 DumpRegion* _dump_region;
822
823 public:
824 WriteClosure(DumpRegion* r) {
825 _dump_region = r;
826 }
827
828 void do_ptr(void** p) {
829 _dump_region->append_intptr_t((intptr_t)*p);
830 }
831
832 void do_u4(u4* p) {
833 void* ptr = (void*)(uintx(*p));
834 do_ptr(&ptr);
835 }
836
837 void do_tag(int tag) {
838 _dump_region->append_intptr_t((intptr_t)tag);
839 }
840
841 void do_oop(oop* o) {
842 if (*o == NULL) {
843 _dump_region->append_intptr_t(0);
844 } else {
845 assert(MetaspaceShared::is_heap_object_archiving_allowed(),
846 "Archiving heap object is not allowed");
847 _dump_region->append_intptr_t(
848 (intptr_t)CompressedOops::encode_not_null(*o));
849 }
850 }
851
852 void do_region(u_char* start, size_t size) {
853 assert((intptr_t)start % sizeof(intptr_t) == 0, "bad alignment");
854 assert(size % sizeof(intptr_t) == 0, "bad size");
855 do_tag((int)size);
856 while (size > 0) {
857 _dump_region->append_intptr_t(*(intptr_t*)start);
858 start += sizeof(intptr_t);
859 size -= sizeof(intptr_t);
860 }
861 }
862
863 bool reading() const { return false; }
864 };
865
866 // This is for dumping detailed statistics for the allocations
867 // in the shared spaces.
868 class DumpAllocStats : public ResourceObj {
869 public:
870
871 // Here's poor man's enum inheritance
872 #define SHAREDSPACE_OBJ_TYPES_DO(f) \
873 METASPACE_OBJ_TYPES_DO(f) \
874 f(SymbolHashentry) \
875 f(SymbolBucket) \
876 f(StringHashentry) \
877 f(StringBucket) \
878 f(Other)
879
880 enum Type {
881 // Types are MetaspaceObj::ClassType, MetaspaceObj::SymbolType, etc
882 SHAREDSPACE_OBJ_TYPES_DO(METASPACE_OBJ_TYPE_DECLARE)
883 _number_of_types
884 };
885
886 static const char * type_name(Type type) {
887 switch(type) {
888 SHAREDSPACE_OBJ_TYPES_DO(METASPACE_OBJ_TYPE_NAME_CASE)
889 default:
890 ShouldNotReachHere();
891 return NULL;
892 }
893 }
894
895 public:
896 enum { RO = 0, RW = 1 };
897
898 int _counts[2][_number_of_types];
899 int _bytes [2][_number_of_types];
900
901 DumpAllocStats() {
902 memset(_counts, 0, sizeof(_counts));
903 memset(_bytes, 0, sizeof(_bytes));
904 };
905
906 void record(MetaspaceObj::Type type, int byte_size, bool read_only) {
907 assert(int(type) >= 0 && type < MetaspaceObj::_number_of_types, "sanity");
908 int which = (read_only) ? RO : RW;
909 _counts[which][type] ++;
910 _bytes [which][type] += byte_size;
911 }
912
913 void record_other_type(int byte_size, bool read_only) {
914 int which = (read_only) ? RO : RW;
915 _bytes [which][OtherType] += byte_size;
916 }
917 void print_stats(int ro_all, int rw_all, int mc_all, int md_all);
918 };
919
920 void DumpAllocStats::print_stats(int ro_all, int rw_all, int mc_all, int md_all) {
921 // Calculate size of data that was not allocated by Metaspace::allocate()
922 MetaspaceSharedStats *stats = MetaspaceShared::stats();
923
924 // symbols
925 _counts[RO][SymbolHashentryType] = stats->symbol.hashentry_count;
926 _bytes [RO][SymbolHashentryType] = stats->symbol.hashentry_bytes;
927
928 _counts[RO][SymbolBucketType] = stats->symbol.bucket_count;
929 _bytes [RO][SymbolBucketType] = stats->symbol.bucket_bytes;
930
931 // strings
932 _counts[RO][StringHashentryType] = stats->string.hashentry_count;
933 _bytes [RO][StringHashentryType] = stats->string.hashentry_bytes;
934
935 _counts[RO][StringBucketType] = stats->string.bucket_count;
936 _bytes [RO][StringBucketType] = stats->string.bucket_bytes;
937
938 // TODO: count things like dictionary, vtable, etc
939 _bytes[RW][OtherType] += mc_all + md_all;
940 rw_all += mc_all + md_all; // mc/md are mapped Read/Write
941
942 // prevent divide-by-zero
943 if (ro_all < 1) {
944 ro_all = 1;
945 }
946 if (rw_all < 1) {
947 rw_all = 1;
948 }
949
950 int all_ro_count = 0;
951 int all_ro_bytes = 0;
952 int all_rw_count = 0;
953 int all_rw_bytes = 0;
954
955 // To make fmt_stats be a syntactic constant (for format warnings), use #define.
956 #define fmt_stats "%-20s: %8d %10d %5.1f | %8d %10d %5.1f | %8d %10d %5.1f"
957 const char *sep = "--------------------+---------------------------+---------------------------+--------------------------";
958 const char *hdr = " ro_cnt ro_bytes % | rw_cnt rw_bytes % | all_cnt all_bytes %";
959
960 LogMessage(cds) msg;
961
962 msg.info("Detailed metadata info (excluding od/st regions; rw stats include md/mc regions):");
963 msg.info("%s", hdr);
964 msg.info("%s", sep);
965 for (int type = 0; type < int(_number_of_types); type ++) {
966 const char *name = type_name((Type)type);
967 int ro_count = _counts[RO][type];
968 int ro_bytes = _bytes [RO][type];
969 int rw_count = _counts[RW][type];
970 int rw_bytes = _bytes [RW][type];
971 int count = ro_count + rw_count;
972 int bytes = ro_bytes + rw_bytes;
973
974 double ro_perc = percent_of(ro_bytes, ro_all);
975 double rw_perc = percent_of(rw_bytes, rw_all);
976 double perc = percent_of(bytes, ro_all + rw_all);
977
978 msg.info(fmt_stats, name,
979 ro_count, ro_bytes, ro_perc,
980 rw_count, rw_bytes, rw_perc,
981 count, bytes, perc);
982
983 all_ro_count += ro_count;
984 all_ro_bytes += ro_bytes;
985 all_rw_count += rw_count;
986 all_rw_bytes += rw_bytes;
987 }
988
989 int all_count = all_ro_count + all_rw_count;
990 int all_bytes = all_ro_bytes + all_rw_bytes;
991
992 double all_ro_perc = percent_of(all_ro_bytes, ro_all);
993 double all_rw_perc = percent_of(all_rw_bytes, rw_all);
994 double all_perc = percent_of(all_bytes, ro_all + rw_all);
995
996 msg.info("%s", sep);
997 msg.info(fmt_stats, "Total",
998 all_ro_count, all_ro_bytes, all_ro_perc,
999 all_rw_count, all_rw_bytes, all_rw_perc,
1000 all_count, all_bytes, all_perc);
1001
1002 assert(all_ro_bytes == ro_all, "everything should have been counted");
1003 assert(all_rw_bytes == rw_all, "everything should have been counted");
1004
1005 #undef fmt_stats
1006 }
1007
1008 // Populate the shared space.
1009
1010 class VM_PopulateDumpSharedSpace: public VM_Operation {
1011 private:
1012 GrowableArray<MemRegion> *_closed_archive_heap_regions;
1013 GrowableArray<MemRegion> *_open_archive_heap_regions;
1014
1015 void dump_java_heap_objects() NOT_CDS_JAVA_HEAP_RETURN;
1016 void dump_symbols();
1017 char* dump_read_only_tables();
1018 void print_region_stats();
1019 void print_heap_region_stats(GrowableArray<MemRegion> *heap_mem,
1020 const char *name, const size_t total_size);
1021 public:
1022
1023 VMOp_Type type() const { return VMOp_PopulateDumpSharedSpace; }
1024 void doit(); // outline because gdb sucks
1025 static void write_region(FileMapInfo* mapinfo, int region, DumpRegion* space, bool read_only, bool allow_exec);
1026 bool allow_nested_vm_operations() const { return true; }
1027 }; // class VM_PopulateDumpSharedSpace
1028
1029 class SortedSymbolClosure: public SymbolClosure {
1030 GrowableArray<Symbol*> _symbols;
1031 virtual void do_symbol(Symbol** sym) {
1032 assert((*sym)->is_permanent(), "archived symbols must be permanent");
1033 _symbols.append(*sym);
1034 }
1035 static int compare_symbols_by_address(Symbol** a, Symbol** b) {
1036 if (a[0] < b[0]) {
1037 return -1;
1038 } else if (a[0] == b[0]) {
1039 return 0;
1040 } else {
1041 return 1;
1042 }
1043 }
1044
1045 public:
1046 SortedSymbolClosure() {
1047 SymbolTable::symbols_do(this);
1048 _symbols.sort(compare_symbols_by_address);
1049 }
1050 GrowableArray<Symbol*>* get_sorted_symbols() {
1051 return &_symbols;
1052 }
1053 };
1054
1055 // ArchiveCompactor --
1056 //
1057 // This class is the central piece of shared archive compaction -- all metaspace data are
1058 // initially allocated outside of the shared regions. ArchiveCompactor copies the
1059 // metaspace data into their final location in the shared regions.
1060
1061 class ArchiveCompactor : AllStatic {
1062 static DumpAllocStats* _alloc_stats;
1063 static SortedSymbolClosure* _ssc;
1064
1065 static unsigned my_hash(const address& a) {
1066 return primitive_hash<address>(a);
1067 }
1068 static bool my_equals(const address& a0, const address& a1) {
1069 return primitive_equals<address>(a0, a1);
1070 }
1071 typedef ResourceHashtable<
1072 address, address,
1073 ArchiveCompactor::my_hash, // solaris compiler doesn't like: primitive_hash<address>
1074 ArchiveCompactor::my_equals, // solaris compiler doesn't like: primitive_equals<address>
1075 16384, ResourceObj::C_HEAP> RelocationTable;
1076 static RelocationTable* _new_loc_table;
1077
1078 public:
1079 static void initialize() {
1080 _alloc_stats = new(ResourceObj::C_HEAP, mtInternal)DumpAllocStats;
1081 _new_loc_table = new(ResourceObj::C_HEAP, mtInternal)RelocationTable;
1082 }
1083 static DumpAllocStats* alloc_stats() {
1084 return _alloc_stats;
1085 }
1086
1087 static void allocate(MetaspaceClosure::Ref* ref, bool read_only) {
1088 address obj = ref->obj();
1089 int bytes = ref->size() * BytesPerWord;
1090 char* p;
1091 size_t alignment = BytesPerWord;
1092 char* oldtop;
1093 char* newtop;
1094
1095 if (read_only) {
1096 oldtop = _ro_region.top();
1097 p = _ro_region.allocate(bytes, alignment);
1098 newtop = _ro_region.top();
1099 } else {
1100 oldtop = _rw_region.top();
1101 p = _rw_region.allocate(bytes, alignment);
1102 newtop = _rw_region.top();
1103 }
1104 memcpy(p, obj, bytes);
1105 bool isnew = _new_loc_table->put(obj, (address)p);
1106 log_trace(cds)("Copy: " PTR_FORMAT " ==> " PTR_FORMAT " %d", p2i(obj), p2i(p), bytes);
1107 assert(isnew, "must be");
1108
1109 _alloc_stats->record(ref->msotype(), int(newtop - oldtop), read_only);
1110 if (ref->msotype() == MetaspaceObj::SymbolType) {
1111 uintx delta = MetaspaceShared::object_delta(p);
1112 if (delta > MAX_SHARED_DELTA) {
1113 // This is just a sanity check and should not appear in any real world usage. This
1114 // happens only if you allocate more than 2GB of Symbols and would require
1115 // millions of shared classes.
1116 vm_exit_during_initialization("Too many Symbols in the CDS archive",
1117 "Please reduce the number of shared classes.");
1118 }
1119 }
1120 }
1121
1122 static address get_new_loc(MetaspaceClosure::Ref* ref) {
1123 address* pp = _new_loc_table->get(ref->obj());
1124 assert(pp != NULL, "must be");
1125 return *pp;
1126 }
1127
1128 private:
1129 // Makes a shallow copy of visited MetaspaceObj's
1130 class ShallowCopier: public UniqueMetaspaceClosure {
1131 bool _read_only;
1132 public:
1133 ShallowCopier(bool read_only) : _read_only(read_only) {}
1134
1135 virtual void do_unique_ref(Ref* ref, bool read_only) {
1136 if (read_only == _read_only) {
1137 allocate(ref, read_only);
1138 }
1139 }
1140 };
1141
1142 // Relocate embedded pointers within a MetaspaceObj's shallow copy
1143 class ShallowCopyEmbeddedRefRelocator: public UniqueMetaspaceClosure {
1144 public:
1145 virtual void do_unique_ref(Ref* ref, bool read_only) {
1146 address new_loc = get_new_loc(ref);
1147 RefRelocator refer;
1148 ref->metaspace_pointers_do_at(&refer, new_loc);
1149 }
1150 };
1151
1152 // Relocate a reference to point to its shallow copy
1153 class RefRelocator: public MetaspaceClosure {
1154 public:
1155 virtual bool do_ref(Ref* ref, bool read_only) {
1156 if (ref->not_null()) {
1157 ref->update(get_new_loc(ref));
1158 }
1159 return false; // Do not recurse.
1160 }
1161 };
1162
1163 #ifdef ASSERT
1164 class IsRefInArchiveChecker: public MetaspaceClosure {
1165 public:
1166 virtual bool do_ref(Ref* ref, bool read_only) {
1167 if (ref->not_null()) {
1168 char* obj = (char*)ref->obj();
1169 assert(_ro_region.contains(obj) || _rw_region.contains(obj),
1170 "must be relocated to point to CDS archive");
1171 }
1172 return false; // Do not recurse.
1173 }
1174 };
1175 #endif
1176
1177 public:
1178 static void copy_and_compact() {
1179 // We should no longer allocate anything from the metaspace, so that
1180 // we can have a stable set of MetaspaceObjs to work with.
1181 Metaspace::freeze();
1182
1183 ResourceMark rm;
1184 SortedSymbolClosure the_ssc; // StackObj
1185 _ssc = &the_ssc;
1186
1187 tty->print_cr("Scanning all metaspace objects ... ");
1188 {
1189 // allocate and shallow-copy RW objects, immediately following the MC region
1190 tty->print_cr("Allocating RW objects ... ");
1191 _mc_region.pack(&_rw_region);
1192
1193 ResourceMark rm;
1194 ShallowCopier rw_copier(false);
1195 iterate_roots(&rw_copier);
1196 }
1197 {
1198 // allocate and shallow-copy of RO object, immediately following the RW region
1199 tty->print_cr("Allocating RO objects ... ");
1200 _rw_region.pack(&_ro_region);
1201
1202 ResourceMark rm;
1203 ShallowCopier ro_copier(true);
1204 iterate_roots(&ro_copier);
1205 }
1206 {
1207 tty->print_cr("Relocating embedded pointers ... ");
1208 ResourceMark rm;
1209 ShallowCopyEmbeddedRefRelocator emb_reloc;
1210 iterate_roots(&emb_reloc);
1211 }
1212 {
1213 tty->print_cr("Relocating external roots ... ");
1214 ResourceMark rm;
1215 RefRelocator ext_reloc;
1216 iterate_roots(&ext_reloc);
1217 }
1218
1219 #ifdef ASSERT
1220 {
1221 tty->print_cr("Verifying external roots ... ");
1222 ResourceMark rm;
1223 IsRefInArchiveChecker checker;
1224 iterate_roots(&checker);
1225 }
1226 #endif
1227
1228
1229 // cleanup
1230 _ssc = NULL;
1231 }
1232
1233 // We must relocate the System::_well_known_klasses only after we have copied the
1234 // java objects in during dump_java_heap_objects(): during the object copy, we operate on
1235 // old objects which assert that their klass is the original klass.
1236 static void relocate_well_known_klasses() {
1237 {
1238 tty->print_cr("Relocating SystemDictionary::_well_known_klasses[] ... ");
1239 ResourceMark rm;
1240 RefRelocator ext_reloc;
1241 SystemDictionary::well_known_klasses_do(&ext_reloc);
1242 }
1243 // NOTE: after this point, we shouldn't have any globals that can reach the old
1244 // objects.
1245
1246 // We cannot use any of the objects in the heap anymore (except for the objects
1247 // in the CDS shared string regions) because their headers no longer point to
1248 // valid Klasses.
1249 }
1250
1251 static void iterate_roots(MetaspaceClosure* it) {
1252 GrowableArray<Symbol*>* symbols = _ssc->get_sorted_symbols();
1253 for (int i=0; i<symbols->length(); i++) {
1254 it->push(symbols->adr_at(i));
1255 }
1256 if (_global_klass_objects != NULL) {
1257 // Need to fix up the pointers
1258 for (int i = 0; i < _global_klass_objects->length(); i++) {
1259 // NOTE -- this requires that the vtable is NOT yet patched, or else we are hosed.
1260 it->push(_global_klass_objects->adr_at(i));
1261 }
1262 }
1263 FileMapInfo::metaspace_pointers_do(it);
1264 SystemDictionary::classes_do(it);
1265 Universe::metaspace_pointers_do(it);
1266 SymbolTable::metaspace_pointers_do(it);
1267 vmSymbols::metaspace_pointers_do(it);
1268 }
1269
1270 static Klass* get_relocated_klass(Klass* orig_klass) {
1271 assert(DumpSharedSpaces, "dump time only");
1272 address* pp = _new_loc_table->get((address)orig_klass);
1273 assert(pp != NULL, "must be");
1274 Klass* klass = (Klass*)(*pp);
1275 assert(klass->is_klass(), "must be");
1276 return klass;
1277 }
1278 };
1279
1280 DumpAllocStats* ArchiveCompactor::_alloc_stats;
1281 SortedSymbolClosure* ArchiveCompactor::_ssc;
1282 ArchiveCompactor::RelocationTable* ArchiveCompactor::_new_loc_table;
1283
1284 void VM_PopulateDumpSharedSpace::write_region(FileMapInfo* mapinfo, int region_idx,
1285 DumpRegion* dump_region, bool read_only, bool allow_exec) {
1286 mapinfo->write_region(region_idx, dump_region->base(), dump_region->used(), read_only, allow_exec);
1287 }
1288
1289 void VM_PopulateDumpSharedSpace::dump_symbols() {
1290 tty->print_cr("Dumping symbol table ...");
1291
1292 NOT_PRODUCT(SymbolTable::verify());
1293 SymbolTable::write_to_archive();
1294 }
1295
1296 char* VM_PopulateDumpSharedSpace::dump_read_only_tables() {
1297 char* oldtop = _ro_region.top();
1298 // Reorder the system dictionary. Moving the symbols affects
1299 // how the hash table indices are calculated.
1300 SystemDictionary::reorder_dictionary_for_sharing();
1301
1302 tty->print("Removing java_mirror ... ");
1303 if (!MetaspaceShared::is_heap_object_archiving_allowed()) {
1304 clear_basic_type_mirrors();
1305 }
1306 remove_java_mirror_in_classes();
1307 tty->print_cr("done. ");
1308 NOT_PRODUCT(SystemDictionary::verify();)
1309
1310 size_t buckets_bytes = SystemDictionary::count_bytes_for_buckets();
1311 char* buckets_top = _ro_region.allocate(buckets_bytes, sizeof(intptr_t));
1312 SystemDictionary::copy_buckets(buckets_top, _ro_region.top());
1313
1314 size_t table_bytes = SystemDictionary::count_bytes_for_table();
1315 char* table_top = _ro_region.allocate(table_bytes, sizeof(intptr_t));
1316 SystemDictionary::copy_table(table_top, _ro_region.top());
1317
1318 // Write the other data to the output array.
1319 WriteClosure wc(&_ro_region);
1320 MetaspaceShared::serialize(&wc);
1321
1322 char* newtop = _ro_region.top();
1323 ArchiveCompactor::alloc_stats()->record_other_type(int(newtop - oldtop), true);
1324 return buckets_top;
1325 }
1326
1327 void VM_PopulateDumpSharedSpace::doit() {
1328 Thread* THREAD = VMThread::vm_thread();
1329
1330 NOT_PRODUCT(SystemDictionary::verify();)
1331 // The following guarantee is meant to ensure that no loader constraints
1332 // exist yet, since the constraints table is not shared. This becomes
1333 // more important now that we don't re-initialize vtables/itables for
1334 // shared classes at runtime, where constraints were previously created.
1335 guarantee(SystemDictionary::constraints()->number_of_entries() == 0,
1336 "loader constraints are not saved");
1337 guarantee(SystemDictionary::placeholders()->number_of_entries() == 0,
1338 "placeholders are not saved");
1339 // Revisit and implement this if we prelink method handle call sites:
1340 guarantee(SystemDictionary::invoke_method_table() == NULL ||
1341 SystemDictionary::invoke_method_table()->number_of_entries() == 0,
1342 "invoke method table is not saved");
1343
1344 // At this point, many classes have been loaded.
1345 // Gather systemDictionary classes in a global array and do everything to
1346 // that so we don't have to walk the SystemDictionary again.
1347 _global_klass_objects = new GrowableArray<Klass*>(1000);
1348 CollectClassesClosure collect_classes;
1349 ClassLoaderDataGraph::loaded_classes_do(&collect_classes);
1350
1351 tty->print_cr("Number of classes %d", _global_klass_objects->length());
1352 {
1353 int num_type_array = 0, num_obj_array = 0, num_inst = 0;
1354 for (int i = 0; i < _global_klass_objects->length(); i++) {
1355 Klass* k = _global_klass_objects->at(i);
1356 if (k->is_instance_klass()) {
1357 num_inst ++;
1358 } else if (k->is_objArray_klass()) {
1359 num_obj_array ++;
1360 } else {
1361 assert(k->is_typeArray_klass(), "sanity");
1362 num_type_array ++;
1363 }
1364 }
1365 tty->print_cr(" instance classes = %5d", num_inst);
1366 tty->print_cr(" obj array classes = %5d", num_obj_array);
1367 tty->print_cr(" type array classes = %5d", num_type_array);
1368 }
1369
1370 // Ensure the ConstMethods won't be modified at run-time
1371 tty->print("Updating ConstMethods ... ");
1372 rewrite_nofast_bytecodes_and_calculate_fingerprints();
1373 tty->print_cr("done. ");
1374
1375 // Move classes from platform/system dictionaries into the boot dictionary
1376 SystemDictionary::combine_shared_dictionaries();
1377
1378 // Remove all references outside the metadata
1379 tty->print("Removing unshareable information ... ");
1380 remove_unshareable_in_classes();
1381 tty->print_cr("done. ");
1382
1383 // We don't support archiving anonymous classes. Verify that they are not stored in
1384 // the any dictionaries.
1385 NOT_PRODUCT(assert_no_anonymoys_classes_in_dictionaries());
1386
1387 SystemDictionaryShared::finalize_verification_constraints();
1388
1389 ArchiveCompactor::initialize();
1390 ArchiveCompactor::copy_and_compact();
1391
1392 dump_symbols();
1393
1394 // Dump supported java heap objects
1395 _closed_archive_heap_regions = NULL;
1396 _open_archive_heap_regions = NULL;
1397 dump_java_heap_objects();
1398
1399 ArchiveCompactor::relocate_well_known_klasses();
1400
1401 char* read_only_tables_start = dump_read_only_tables();
1402 _ro_region.pack(&_md_region);
1403
1404 char* vtbl_list = _md_region.top();
1405 MetaspaceShared::allocate_cpp_vtable_clones();
1406 _md_region.pack(&_od_region);
1407
1408 // Relocate the archived class file data into the od region
1409 relocate_cached_class_file();
1410 _od_region.pack();
1411
1412 // The 5 core spaces are allocated consecutively mc->rw->ro->md->od, so there total size
1413 // is just the spaces between the two ends.
1414 size_t core_spaces_size = _od_region.end() - _mc_region.base();
1415 assert(core_spaces_size == (size_t)align_up(core_spaces_size, Metaspace::reserve_alignment()),
1416 "should already be aligned");
1417
1418 // During patching, some virtual methods may be called, so at this point
1419 // the vtables must contain valid methods (as filled in by CppVtableCloner::allocate).
1420 MetaspaceShared::patch_cpp_vtable_pointers();
1421
1422 // The vtable clones contain addresses of the current process.
1423 // We don't want to write these addresses into the archive.
1424 MetaspaceShared::zero_cpp_vtable_clones_for_writing();
1425
1426 // Create and write the archive file that maps the shared spaces.
1427
1428 FileMapInfo* mapinfo = new FileMapInfo();
1429 mapinfo->populate_header(os::vm_allocation_granularity());
1430 mapinfo->set_read_only_tables_start(read_only_tables_start);
1431 mapinfo->set_misc_data_patching_start(vtbl_list);
1432 mapinfo->set_cds_i2i_entry_code_buffers(MetaspaceShared::cds_i2i_entry_code_buffers());
1433 mapinfo->set_cds_i2i_entry_code_buffers_size(MetaspaceShared::cds_i2i_entry_code_buffers_size());
1434 mapinfo->set_core_spaces_size(core_spaces_size);
1435
1436 for (int pass=1; pass<=2; pass++) {
1437 if (pass == 1) {
1438 // The first pass doesn't actually write the data to disk. All it
1439 // does is to update the fields in the mapinfo->_header.
1440 } else {
1441 // After the first pass, the contents of mapinfo->_header are finalized,
1442 // so we can compute the header's CRC, and write the contents of the header
1443 // and the regions into disk.
1444 mapinfo->open_for_write();
1445 mapinfo->set_header_crc(mapinfo->compute_header_crc());
1446 }
1447 mapinfo->write_header();
1448
1449 // NOTE: md contains the trampoline code for method entries, which are patched at run time,
1450 // so it needs to be read/write.
1451 write_region(mapinfo, MetaspaceShared::mc, &_mc_region, /*read_only=*/false,/*allow_exec=*/true);
1452 write_region(mapinfo, MetaspaceShared::rw, &_rw_region, /*read_only=*/false,/*allow_exec=*/false);
1453 write_region(mapinfo, MetaspaceShared::ro, &_ro_region, /*read_only=*/true, /*allow_exec=*/false);
1454 write_region(mapinfo, MetaspaceShared::md, &_md_region, /*read_only=*/false,/*allow_exec=*/false);
1455 write_region(mapinfo, MetaspaceShared::od, &_od_region, /*read_only=*/true, /*allow_exec=*/false);
1456
1457 _total_string_region_size = mapinfo->write_archive_heap_regions(
1458 _closed_archive_heap_regions,
1459 MetaspaceShared::first_string,
1460 MetaspaceShared::max_strings);
1461 _total_open_archive_region_size = mapinfo->write_archive_heap_regions(
1462 _open_archive_heap_regions,
1463 MetaspaceShared::first_open_archive_heap_region,
1464 MetaspaceShared::max_open_archive_heap_region);
1465 }
1466
1467 mapinfo->close();
1468
1469 // Restore the vtable in case we invoke any virtual methods.
1470 MetaspaceShared::clone_cpp_vtables((intptr_t*)vtbl_list);
1471
1472 print_region_stats();
1473
1474 if (log_is_enabled(Info, cds)) {
1475 ArchiveCompactor::alloc_stats()->print_stats(int(_ro_region.used()), int(_rw_region.used()),
1476 int(_mc_region.used()), int(_md_region.used()));
1477 }
1478
1479 if (PrintSystemDictionaryAtExit) {
1480 SystemDictionary::print();
1481 }
1482 // There may be other pending VM operations that operate on the InstanceKlasses,
1483 // which will fail because InstanceKlasses::remove_unshareable_info()
1484 // has been called. Forget these operations and exit the VM directly.
1485 vm_direct_exit(0);
1486 }
1487
1488 void VM_PopulateDumpSharedSpace::print_region_stats() {
1489 // Print statistics of all the regions
1490 const size_t total_reserved = _ro_region.reserved() + _rw_region.reserved() +
1491 _mc_region.reserved() + _md_region.reserved() +
1492 _od_region.reserved() +
1493 _total_string_region_size +
1494 _total_open_archive_region_size;
1495 const size_t total_bytes = _ro_region.used() + _rw_region.used() +
1496 _mc_region.used() + _md_region.used() +
1497 _od_region.used() +
1498 _total_string_region_size +
1499 _total_open_archive_region_size;
1500 const double total_u_perc = percent_of(total_bytes, total_reserved);
1501
1502 _mc_region.print(total_reserved);
1503 _rw_region.print(total_reserved);
1504 _ro_region.print(total_reserved);
1505 _md_region.print(total_reserved);
1506 _od_region.print(total_reserved);
1507 print_heap_region_stats(_closed_archive_heap_regions, "st", total_reserved);
1508 print_heap_region_stats(_open_archive_heap_regions, "oa", total_reserved);
1509
1510 tty->print_cr("total : " SIZE_FORMAT_W(9) " [100.0%% of total] out of " SIZE_FORMAT_W(9) " bytes [%5.1f%% used]",
1511 total_bytes, total_reserved, total_u_perc);
1512 }
1513
1514 void VM_PopulateDumpSharedSpace::print_heap_region_stats(GrowableArray<MemRegion> *heap_mem,
1515 const char *name, const size_t total_size) {
1516 int arr_len = heap_mem == NULL ? 0 : heap_mem->length();
1517 for (int i = 0; i < arr_len; i++) {
1518 char* start = (char*)heap_mem->at(i).start();
1519 size_t size = heap_mem->at(i).byte_size();
1520 char* top = start + size;
1521 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,
1522 name, i, size, size/double(total_size)*100.0, size, p2i(start));
1523
1524 }
1525 }
1526
1527 // Update a Java object to point its Klass* to the new location after
1528 // shared archive has been compacted.
1529 void MetaspaceShared::relocate_klass_ptr(oop o) {
1530 assert(DumpSharedSpaces, "sanity");
1531 Klass* k = ArchiveCompactor::get_relocated_klass(o->klass());
1532 o->set_klass(k);
1533 }
1534
1535 Klass* MetaspaceShared::get_relocated_klass(Klass *k) {
1536 assert(DumpSharedSpaces, "sanity");
1537 return ArchiveCompactor::get_relocated_klass(k);
1538 }
1539
1540 class LinkSharedClassesClosure : public KlassClosure {
1541 Thread* THREAD;
1542 bool _made_progress;
1543 public:
1544 LinkSharedClassesClosure(Thread* thread) : THREAD(thread), _made_progress(false) {}
1545
1546 void reset() { _made_progress = false; }
1547 bool made_progress() const { return _made_progress; }
1548
1549 void do_klass(Klass* k) {
1550 if (k->is_instance_klass()) {
1551 InstanceKlass* ik = InstanceKlass::cast(k);
1552 // Link the class to cause the bytecodes to be rewritten and the
1553 // cpcache to be created. Class verification is done according
1554 // to -Xverify setting.
1555 _made_progress |= MetaspaceShared::try_link_class(ik, THREAD);
1556 guarantee(!HAS_PENDING_EXCEPTION, "exception in link_class");
1557
1558 ik->constants()->resolve_class_constants(THREAD);
1559 }
1560 }
1561 };
1562
1563 class CheckSharedClassesClosure : public KlassClosure {
1564 bool _made_progress;
1565 public:
1566 CheckSharedClassesClosure() : _made_progress(false) {}
1567
1568 void reset() { _made_progress = false; }
1569 bool made_progress() const { return _made_progress; }
1570 void do_klass(Klass* k) {
1571 if (k->is_instance_klass() && InstanceKlass::cast(k)->check_sharing_error_state()) {
1572 _made_progress = true;
1573 }
1574 }
1575 };
1576
1577 void MetaspaceShared::check_shared_class_loader_type(Klass* k) {
1578 if (k->is_instance_klass()) {
1579 InstanceKlass* ik = InstanceKlass::cast(k);
1580 u2 loader_type = ik->loader_type();
1581 ResourceMark rm;
1582 guarantee(loader_type != 0,
1583 "Class loader type is not set for this class %s", ik->name()->as_C_string());
1584 }
1585 }
1586
1587 void MetaspaceShared::link_and_cleanup_shared_classes(TRAPS) {
1588 // We need to iterate because verification may cause additional classes
1589 // to be loaded.
1590 LinkSharedClassesClosure link_closure(THREAD);
1591 do {
1592 link_closure.reset();
1593 ClassLoaderDataGraph::loaded_classes_do(&link_closure);
1594 guarantee(!HAS_PENDING_EXCEPTION, "exception in link_class");
1595 } while (link_closure.made_progress());
1596
1597 if (_has_error_classes) {
1598 // Mark all classes whose super class or interfaces failed verification.
1599 CheckSharedClassesClosure check_closure;
1600 do {
1601 // Not completely sure if we need to do this iteratively. Anyway,
1602 // we should come here only if there are unverifiable classes, which
1603 // shouldn't happen in normal cases. So better safe than sorry.
1604 check_closure.reset();
1605 ClassLoaderDataGraph::loaded_classes_do(&check_closure);
1606 } while (check_closure.made_progress());
1607
1608 if (IgnoreUnverifiableClassesDuringDump) {
1609 // This is useful when running JCK or SQE tests. You should not
1610 // enable this when running real apps.
1611 SystemDictionary::remove_classes_in_error_state();
1612 } else {
1613 tty->print_cr("Please remove the unverifiable classes from your class list and try again");
1614 exit(1);
1615 }
1616 }
1617 }
1618
1619 void MetaspaceShared::prepare_for_dumping() {
1620 Arguments::check_unsupported_dumping_properties();
1621 ClassLoader::initialize_shared_path();
1622 }
1623
1624 // Preload classes from a list, populate the shared spaces and dump to a
1625 // file.
1626 void MetaspaceShared::preload_and_dump(TRAPS) {
1627 { TraceTime timer("Dump Shared Spaces", TRACETIME_LOG(Info, startuptime));
1628 ResourceMark rm;
1629 char class_list_path_str[JVM_MAXPATHLEN];
1630 // Preload classes to be shared.
1631 // Should use some os:: method rather than fopen() here. aB.
1632 const char* class_list_path;
1633 if (SharedClassListFile == NULL) {
1634 // Construct the path to the class list (in jre/lib)
1635 // Walk up two directories from the location of the VM and
1636 // optionally tack on "lib" (depending on platform)
1637 os::jvm_path(class_list_path_str, sizeof(class_list_path_str));
1638 for (int i = 0; i < 3; i++) {
1639 char *end = strrchr(class_list_path_str, *os::file_separator());
1640 if (end != NULL) *end = '\0';
1641 }
1642 int class_list_path_len = (int)strlen(class_list_path_str);
1643 if (class_list_path_len >= 3) {
1644 if (strcmp(class_list_path_str + class_list_path_len - 3, "lib") != 0) {
1645 if (class_list_path_len < JVM_MAXPATHLEN - 4) {
1646 jio_snprintf(class_list_path_str + class_list_path_len,
1647 sizeof(class_list_path_str) - class_list_path_len,
1648 "%slib", os::file_separator());
1649 class_list_path_len += 4;
1650 }
1651 }
1652 }
1653 if (class_list_path_len < JVM_MAXPATHLEN - 10) {
1654 jio_snprintf(class_list_path_str + class_list_path_len,
1655 sizeof(class_list_path_str) - class_list_path_len,
1656 "%sclasslist", os::file_separator());
1657 }
1658 class_list_path = class_list_path_str;
1659 } else {
1660 class_list_path = SharedClassListFile;
1661 }
1662
1663 tty->print_cr("Loading classes to share ...");
1664 _has_error_classes = false;
1665 int class_count = preload_classes(class_list_path, THREAD);
1666 if (ExtraSharedClassListFile) {
1667 class_count += preload_classes(ExtraSharedClassListFile, THREAD);
1668 }
1669 tty->print_cr("Loading classes to share: done.");
1670
1671 log_info(cds)("Shared spaces: preloaded %d classes", class_count);
1672
1673 // Rewrite and link classes
1674 tty->print_cr("Rewriting and linking classes ...");
1675
1676 // Link any classes which got missed. This would happen if we have loaded classes that
1677 // were not explicitly specified in the classlist. E.g., if an interface implemented by class K
1678 // fails verification, all other interfaces that were not specified in the classlist but
1679 // are implemented by K are not verified.
1680 link_and_cleanup_shared_classes(CATCH);
1681 tty->print_cr("Rewriting and linking classes: done");
1682
1683 SystemDictionary::clear_invoke_method_table();
1684
1685 VM_PopulateDumpSharedSpace op;
1686 VMThread::execute(&op);
1687 }
1688 }
1689
1690
1691 int MetaspaceShared::preload_classes(const char* class_list_path, TRAPS) {
1692 ClassListParser parser(class_list_path);
1693 int class_count = 0;
1694
1695 while (parser.parse_one_line()) {
1696 Klass* klass = ClassLoaderExt::load_one_class(&parser, THREAD);
1697 if (HAS_PENDING_EXCEPTION) {
1698 if (klass == NULL &&
1699 (PENDING_EXCEPTION->klass()->name() == vmSymbols::java_lang_ClassNotFoundException())) {
1700 // print a warning only when the pending exception is class not found
1701 tty->print_cr("Preload Warning: Cannot find %s", parser.current_class_name());
1702 }
1703 CLEAR_PENDING_EXCEPTION;
1704 }
1705 if (klass != NULL) {
1706 if (log_is_enabled(Trace, cds)) {
1707 ResourceMark rm;
1708 log_trace(cds)("Shared spaces preloaded: %s", klass->external_name());
1709 }
1710
1711 if (klass->is_instance_klass()) {
1712 InstanceKlass* ik = InstanceKlass::cast(klass);
1713
1714 // Link the class to cause the bytecodes to be rewritten and the
1715 // cpcache to be created. The linking is done as soon as classes
1716 // are loaded in order that the related data structures (klass and
1717 // cpCache) are located together.
1718 try_link_class(ik, THREAD);
1719 guarantee(!HAS_PENDING_EXCEPTION, "exception in link_class");
1720 }
1721
1722 class_count++;
1723 }
1724 }
1725
1726 return class_count;
1727 }
1728
1729 // Returns true if the class's status has changed
1730 bool MetaspaceShared::try_link_class(InstanceKlass* ik, TRAPS) {
1731 assert(DumpSharedSpaces, "should only be called during dumping");
1732 if (ik->init_state() < InstanceKlass::linked) {
1733 bool saved = BytecodeVerificationLocal;
1734 if (ik->loader_type() == 0 && ik->class_loader() == NULL) {
1735 // The verification decision is based on BytecodeVerificationRemote
1736 // for non-system classes. Since we are using the NULL classloader
1737 // to load non-system classes for customized class loaders during dumping,
1738 // we need to temporarily change BytecodeVerificationLocal to be the same as
1739 // BytecodeVerificationRemote. Note this can cause the parent system
1740 // classes also being verified. The extra overhead is acceptable during
1741 // dumping.
1742 BytecodeVerificationLocal = BytecodeVerificationRemote;
1743 }
1744 ik->link_class(THREAD);
1745 if (HAS_PENDING_EXCEPTION) {
1746 ResourceMark rm;
1747 tty->print_cr("Preload Warning: Verification failed for %s",
1748 ik->external_name());
1749 CLEAR_PENDING_EXCEPTION;
1750 ik->set_in_error_state();
1751 _has_error_classes = true;
1752 }
1753 BytecodeVerificationLocal = saved;
1754 return true;
1755 } else {
1756 return false;
1757 }
1758 }
1759
1760 #if INCLUDE_CDS_JAVA_HEAP
1761 void VM_PopulateDumpSharedSpace::dump_java_heap_objects() {
1762 if (!MetaspaceShared::is_heap_object_archiving_allowed()) {
1763 if (log_is_enabled(Info, cds)) {
1764 log_info(cds)(
1765 "Archived java heap is not supported as UseG1GC, "
1766 "UseCompressedOops and UseCompressedClassPointers are required."
1767 "Current settings: UseG1GC=%s, UseCompressedOops=%s, UseCompressedClassPointers=%s.",
1768 BOOL_TO_STR(UseG1GC), BOOL_TO_STR(UseCompressedOops),
1769 BOOL_TO_STR(UseCompressedClassPointers));
1770 }
1771 return;
1772 }
1773
1774 {
1775 NoSafepointVerifier nsv;
1776
1777 // Cache for recording where the archived objects are copied to
1778 MetaspaceShared::create_archive_object_cache();
1779
1780 tty->print_cr("Dumping objects to closed archive heap region ...");
1781 NOT_PRODUCT(StringTable::verify());
1782 // The closed space has maximum two regions. See FileMapInfo::write_archive_heap_regions() for details.
1783 _closed_archive_heap_regions = new GrowableArray<MemRegion>(2);
1784 MetaspaceShared::dump_closed_archive_heap_objects(_closed_archive_heap_regions);
1785
1786 tty->print_cr("Dumping objects to open archive heap region ...");
1787 _open_archive_heap_regions = new GrowableArray<MemRegion>(2);
1788 MetaspaceShared::dump_open_archive_heap_objects(_open_archive_heap_regions);
1789
1790 MetaspaceShared::destroy_archive_object_cache();
1791 }
1792
1793 G1HeapVerifier::verify_archive_regions();
1794 }
1795
1796 void MetaspaceShared::dump_closed_archive_heap_objects(
1797 GrowableArray<MemRegion> * closed_archive) {
1798 assert(is_heap_object_archiving_allowed(), "Cannot dump java heap objects");
1799
1800 Thread* THREAD = Thread::current();
1801 G1CollectedHeap::heap()->begin_archive_alloc_range();
1802
1803 // Archive interned string objects
1804 StringTable::write_to_archive(closed_archive);
1805
1806 G1CollectedHeap::heap()->end_archive_alloc_range(closed_archive,
1807 os::vm_allocation_granularity());
1808 }
1809
1810 void MetaspaceShared::dump_open_archive_heap_objects(
1811 GrowableArray<MemRegion> * open_archive) {
1812 assert(UseG1GC, "Only support G1 GC");
1813 assert(UseCompressedOops && UseCompressedClassPointers,
1814 "Only support UseCompressedOops and UseCompressedClassPointers enabled");
1815
1816 Thread* THREAD = Thread::current();
1817 G1CollectedHeap::heap()->begin_archive_alloc_range(true /* open */);
1818
1819 java_lang_Class::archive_basic_type_mirrors(THREAD);
1820
1821 MetaspaceShared::archive_klass_objects(THREAD);
1822
1823 G1CollectedHeap::heap()->end_archive_alloc_range(open_archive,
1824 os::vm_allocation_granularity());
1825 }
1826
1827 unsigned MetaspaceShared::obj_hash(oop const& p) {
1828 assert(!p->mark()->has_bias_pattern(),
1829 "this object should never have been locked"); // so identity_hash won't safepoin
1830 unsigned hash = (unsigned)p->identity_hash();
1831 return hash;
1832 }
1833
1834 MetaspaceShared::ArchivedObjectCache* MetaspaceShared::_archive_object_cache = NULL;
1835 oop MetaspaceShared::find_archived_heap_object(oop obj) {
1836 assert(DumpSharedSpaces, "dump-time only");
1837 ArchivedObjectCache* cache = MetaspaceShared::archive_object_cache();
1838 oop* p = cache->get(obj);
1839 if (p != NULL) {
1840 return *p;
1841 } else {
1842 return NULL;
1843 }
1844 }
1845
1846 oop MetaspaceShared::archive_heap_object(oop obj, Thread* THREAD) {
1847 assert(DumpSharedSpaces, "dump-time only");
1848
1849 oop ao = find_archived_heap_object(obj);
1850 if (ao != NULL) {
1851 // already archived
1852 return ao;
1853 }
1854
1855 int len = obj->size();
1856 if (G1CollectedHeap::heap()->is_archive_alloc_too_large(len)) {
1857 return NULL;
1858 }
1859
1860 int hash = obj->identity_hash();
1861 oop archived_oop = (oop)G1CollectedHeap::heap()->archive_mem_allocate(len);
1862 if (archived_oop != NULL) {
1863 Copy::aligned_disjoint_words((HeapWord*)obj, (HeapWord*)archived_oop, len);
1864 relocate_klass_ptr(archived_oop);
1865 ArchivedObjectCache* cache = MetaspaceShared::archive_object_cache();
1866 cache->put(obj, archived_oop);
1867 }
1868 log_debug(cds)("Archived heap object " PTR_FORMAT " ==> " PTR_FORMAT,
1869 p2i(obj), p2i(archived_oop));
1870 return archived_oop;
1871 }
1872
1873 void MetaspaceShared::archive_klass_objects(Thread* THREAD) {
1874 int i;
1875 for (i = 0; i < _global_klass_objects->length(); i++) {
1876 Klass* k = _global_klass_objects->at(i);
1877
1878 // archive mirror object
1879 java_lang_Class::archive_mirror(k, CHECK);
1880
1881 // archive the resolved_referenes array
1882 if (k->is_instance_klass()) {
1883 InstanceKlass* ik = InstanceKlass::cast(k);
1884 ik->constants()->archive_resolved_references(THREAD);
1885 }
1886 }
1887 }
1888
1889 void MetaspaceShared::fixup_mapped_heap_regions() {
1890 FileMapInfo *mapinfo = FileMapInfo::current_info();
1891 mapinfo->fixup_mapped_heap_regions();
1892 }
1893 #endif // INCLUDE_CDS_JAVA_HEAP
1894
1895 // Closure for serializing initialization data in from a data area
1896 // (ptr_array) read from the shared file.
1897
1898 class ReadClosure : public SerializeClosure {
1899 private:
1900 intptr_t** _ptr_array;
1901
1902 inline intptr_t nextPtr() {
1903 return *(*_ptr_array)++;
1904 }
1905
1906 public:
1907 ReadClosure(intptr_t** ptr_array) { _ptr_array = ptr_array; }
1908
1909 void do_ptr(void** p) {
1910 assert(*p == NULL, "initializing previous initialized pointer.");
1911 intptr_t obj = nextPtr();
1912 assert((intptr_t)obj >= 0 || (intptr_t)obj < -100,
1913 "hit tag while initializing ptrs.");
1914 *p = (void*)obj;
1915 }
1916
1917 void do_u4(u4* p) {
1918 intptr_t obj = nextPtr();
1919 *p = (u4)(uintx(obj));
1920 }
1921
1922 void do_tag(int tag) {
1923 int old_tag;
1924 old_tag = (int)(intptr_t)nextPtr();
1925 // do_int(&old_tag);
1926 assert(tag == old_tag, "old tag doesn't match");
1927 FileMapInfo::assert_mark(tag == old_tag);
1928 }
1929
1930 void do_oop(oop *p) {
1931 narrowOop o = (narrowOop)nextPtr();
1932 if (o == 0 || !MetaspaceShared::open_archive_heap_region_mapped()) {
1933 p = NULL;
1934 } else {
1935 assert(MetaspaceShared::is_heap_object_archiving_allowed(),
1936 "Archived heap object is not allowed");
1937 assert(MetaspaceShared::open_archive_heap_region_mapped(),
1938 "Open archive heap region is not mapped");
1939 RootAccess<IN_ARCHIVE_ROOT>::oop_store(p, CompressedOops::decode_not_null(o));
1940 }
1941 }
1942
1943 void do_region(u_char* start, size_t size) {
1944 assert((intptr_t)start % sizeof(intptr_t) == 0, "bad alignment");
1945 assert(size % sizeof(intptr_t) == 0, "bad size");
1946 do_tag((int)size);
1947 while (size > 0) {
1948 *(intptr_t*)start = nextPtr();
1949 start += sizeof(intptr_t);
1950 size -= sizeof(intptr_t);
1951 }
1952 }
1953
1954 bool reading() const { return true; }
1955 };
1956
1957 // Return true if given address is in the misc data region
1958 bool MetaspaceShared::is_in_shared_region(const void* p, int idx) {
1959 return UseSharedSpaces && FileMapInfo::current_info()->is_in_shared_region(p, idx);
1960 }
1961
1962 bool MetaspaceShared::is_in_trampoline_frame(address addr) {
1963 if (UseSharedSpaces && is_in_shared_region(addr, MetaspaceShared::mc)) {
1964 return true;
1965 }
1966 return false;
1967 }
1968
1969 void MetaspaceShared::print_shared_spaces() {
1970 if (UseSharedSpaces) {
1971 FileMapInfo::current_info()->print_shared_spaces();
1972 }
1973 }
1974
1975
1976 // Map shared spaces at requested addresses and return if succeeded.
1977 bool MetaspaceShared::map_shared_spaces(FileMapInfo* mapinfo) {
1978 size_t image_alignment = mapinfo->alignment();
1979
1980 #ifndef _WINDOWS
1981 // Map in the shared memory and then map the regions on top of it.
1982 // On Windows, don't map the memory here because it will cause the
1983 // mappings of the regions to fail.
1984 ReservedSpace shared_rs = mapinfo->reserve_shared_memory();
1985 if (!shared_rs.is_reserved()) return false;
1986 #endif
1987
1988 assert(!DumpSharedSpaces, "Should not be called with DumpSharedSpaces");
1989
1990 char* ro_base = NULL; char* ro_top;
1991 char* rw_base = NULL; char* rw_top;
1992 char* mc_base = NULL; char* mc_top;
1993 char* md_base = NULL; char* md_top;
1994 char* od_base = NULL; char* od_top;
1995
1996 // Map each shared region
1997 if ((mc_base = mapinfo->map_region(mc, &mc_top)) != NULL &&
1998 (rw_base = mapinfo->map_region(rw, &rw_top)) != NULL &&
1999 (ro_base = mapinfo->map_region(ro, &ro_top)) != NULL &&
2000 (md_base = mapinfo->map_region(md, &md_top)) != NULL &&
2001 (od_base = mapinfo->map_region(od, &od_top)) != NULL &&
2002 (image_alignment == (size_t)os::vm_allocation_granularity()) &&
2003 mapinfo->validate_shared_path_table()) {
2004 // Success -- set up MetaspaceObj::_shared_metaspace_{base,top} for
2005 // fast checking in MetaspaceShared::is_in_shared_metaspace() and
2006 // MetaspaceObj::is_shared().
2007 //
2008 // We require that mc->rw->ro->md->od to be laid out consecutively, with no
2009 // gaps between them. That way, we can ensure that the OS won't be able to
2010 // allocate any new memory spaces inside _shared_metaspace_{base,top}, which
2011 // would mess up the simple comparision in MetaspaceShared::is_in_shared_metaspace().
2012 assert(mc_base < ro_base && mc_base < rw_base && mc_base < md_base && mc_base < od_base, "must be");
2013 assert(od_top > ro_top && od_top > rw_top && od_top > md_top && od_top > mc_top , "must be");
2014 assert(mc_top == rw_base, "must be");
2015 assert(rw_top == ro_base, "must be");
2016 assert(ro_top == md_base, "must be");
2017 assert(md_top == od_base, "must be");
2018
2019 MetaspaceObj::_shared_metaspace_base = (void*)mc_base;
2020 MetaspaceObj::_shared_metaspace_top = (void*)od_top;
2021 return true;
2022 } else {
2023 // If there was a failure in mapping any of the spaces, unmap the ones
2024 // that succeeded
2025 if (ro_base != NULL) mapinfo->unmap_region(ro);
2026 if (rw_base != NULL) mapinfo->unmap_region(rw);
2027 if (mc_base != NULL) mapinfo->unmap_region(mc);
2028 if (md_base != NULL) mapinfo->unmap_region(md);
2029 if (od_base != NULL) mapinfo->unmap_region(od);
2030 #ifndef _WINDOWS
2031 // Release the entire mapped region
2032 shared_rs.release();
2033 #endif
2034 // If -Xshare:on is specified, print out the error message and exit VM,
2035 // otherwise, set UseSharedSpaces to false and continue.
2036 if (RequireSharedSpaces || PrintSharedArchiveAndExit) {
2037 vm_exit_during_initialization("Unable to use shared archive.", "Failed map_region for using -Xshare:on.");
2038 } else {
2039 FLAG_SET_DEFAULT(UseSharedSpaces, false);
2040 }
2041 return false;
2042 }
2043 }
2044
2045 // Read the miscellaneous data from the shared file, and
2046 // serialize it out to its various destinations.
2047
2048 void MetaspaceShared::initialize_shared_spaces() {
2049 FileMapInfo *mapinfo = FileMapInfo::current_info();
2050 _cds_i2i_entry_code_buffers = mapinfo->cds_i2i_entry_code_buffers();
2051 _cds_i2i_entry_code_buffers_size = mapinfo->cds_i2i_entry_code_buffers_size();
2052 _core_spaces_size = mapinfo->core_spaces_size();
2053 char* buffer = mapinfo->misc_data_patching_start();
2054 clone_cpp_vtables((intptr_t*)buffer);
2055
2056 // The rest of the data is now stored in the RW region
2057 buffer = mapinfo->read_only_tables_start();
2058 int sharedDictionaryLen = *(intptr_t*)buffer;
2059 buffer += sizeof(intptr_t);
2060 int number_of_entries = *(intptr_t*)buffer;
2061 buffer += sizeof(intptr_t);
2062 SystemDictionary::set_shared_dictionary((HashtableBucket<mtClass>*)buffer,
2063 sharedDictionaryLen,
2064 number_of_entries);
2065 buffer += sharedDictionaryLen;
2066
2067 // The following data are the linked list elements
2068 // (HashtableEntry objects) for the shared dictionary table.
2069
2070 int len = *(intptr_t*)buffer; // skip over shared dictionary entries
2071 buffer += sizeof(intptr_t);
2072 buffer += len;
2073
2074 // Verify various attributes of the archive, plus initialize the
2075 // shared string/symbol tables
2076 intptr_t* array = (intptr_t*)buffer;
2077 ReadClosure rc(&array);
2078 serialize(&rc);
2079
2080 // Initialize the run-time symbol table.
2081 SymbolTable::create_table();
2082
2083 // Close the mapinfo file
2084 mapinfo->close();
2085
2086 if (PrintSharedArchiveAndExit) {
2087 if (PrintSharedDictionary) {
2088 tty->print_cr("\nShared classes:\n");
2089 SystemDictionary::print_shared(tty);
2090 }
2091 if (_archive_loading_failed) {
2092 tty->print_cr("archive is invalid");
2093 vm_exit(1);
2094 } else {
2095 tty->print_cr("archive is valid");
2096 vm_exit(0);
2097 }
2098 }
2099 }
2100
2101 // JVM/TI RedefineClasses() support:
2102 bool MetaspaceShared::remap_shared_readonly_as_readwrite() {
2103 assert(SafepointSynchronize::is_at_safepoint(), "must be at safepoint");
2104
2105 if (UseSharedSpaces) {
2106 // remap the shared readonly space to shared readwrite, private
2107 FileMapInfo* mapinfo = FileMapInfo::current_info();
2108 if (!mapinfo->remap_shared_readonly_as_readwrite()) {
2109 return false;
2110 }
2111 _remapped_readwrite = true;
2112 }
2113 return true;
2114 }
2115
2116 void MetaspaceShared::report_out_of_space(const char* name, size_t needed_bytes) {
2117 // This is highly unlikely to happen on 64-bits because we have reserved a 4GB space.
2118 // On 32-bit we reserve only 256MB so you could run out of space with 100,000 classes
2119 // or so.
2120 _mc_region.print_out_of_space_msg(name, needed_bytes);
2121 _rw_region.print_out_of_space_msg(name, needed_bytes);
2122 _ro_region.print_out_of_space_msg(name, needed_bytes);
2123 _md_region.print_out_of_space_msg(name, needed_bytes);
2124 _od_region.print_out_of_space_msg(name, needed_bytes);
2125
2126 vm_exit_during_initialization(err_msg("Unable to allocate from '%s' region", name),
2127 "Please reduce the number of shared classes.");
2128 }