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