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 #if INCLUDE_ALL_GCS
39 #include "gc/g1/g1Allocator.inline.hpp"
40 #include "gc/g1/g1CollectedHeap.hpp"
41 #include "gc/g1/g1SATBCardTableModRefBS.hpp"
42 #endif
43 #include "gc/shared/gcLocker.hpp"
44 #include "interpreter/bytecodeStream.hpp"
45 #include "interpreter/bytecodes.hpp"
46 #include "logging/log.hpp"
47 #include "logging/logMessage.hpp"
48 #include "memory/filemap.hpp"
49 #include "memory/metaspace.hpp"
50 #include "memory/metaspaceShared.hpp"
51 #include "memory/resourceArea.hpp"
52 #include "oops/instanceClassLoaderKlass.hpp"
53 #include "oops/instanceMirrorKlass.hpp"
54 #include "oops/instanceRefKlass.hpp"
55 #include "oops/objArrayKlass.hpp"
56 #include "oops/objArrayOop.hpp"
57 #include "oops/oop.inline.hpp"
58 #include "oops/typeArrayKlass.hpp"
59 #include "prims/jvmtiRedefineClasses.hpp"
60 #include "runtime/timerTrace.hpp"
61 #include "runtime/os.hpp"
62 #include "runtime/signature.hpp"
63 #include "runtime/vmThread.hpp"
64 #include "runtime/vm_operations.hpp"
65 #include "utilities/align.hpp"
66 #include "utilities/defaultStream.hpp"
67 #include "utilities/hashtable.inline.hpp"
68 #include "memory/metaspaceClosure.hpp"
69
70 ReservedSpace MetaspaceShared::_shared_rs;
71 VirtualSpace MetaspaceShared::_shared_vs;
72 MetaspaceSharedStats MetaspaceShared::_stats;
73 bool MetaspaceShared::_has_error_classes;
74 bool MetaspaceShared::_archive_loading_failed = false;
75 bool MetaspaceShared::_remapped_readwrite = false;
76 bool MetaspaceShared::_open_archive_heap_region_mapped = false;
77 address MetaspaceShared::_cds_i2i_entry_code_buffers = NULL;
78 size_t MetaspaceShared::_cds_i2i_entry_code_buffers_size = 0;
79 size_t MetaspaceShared::_core_spaces_size = 0;
80
81 // The CDS archive is divided into the following regions:
82 // mc - misc code (the method entry trampolines)
83 // rw - read-write metadata
84 // ro - read-only metadata and read-only tables
85 // md - misc data (the c++ vtables)
86 // od - optional data (original class files)
87 //
88 // s0 - shared strings(closed archive heap space) #0
89 // s1 - shared strings(closed archive heap space) #1 (may be empty)
90 // oa0 - open archive heap space #0
91 // oa1 - open archive heap space #1 (may be empty)
92 //
93 // The mc, rw, ro, md and od regions are linearly allocated, starting from
94 // SharedBaseAddress, in the order of mc->rw->ro->md->od. The size of these 5 regions
95 // are page-aligned, and there's no gap between any consecutive regions.
96 //
97 // These 5 regions are populated in the following steps:
98 // [1] All classes are loaded in MetaspaceShared::preload_classes(). All metadata are
99 // temporarily allocated outside of the shared regions. Only the method entry
100 // trampolines are written into the mc region.
101 // [2] ArchiveCompactor copies RW metadata into the rw region.
102 // [3] ArchiveCompactor copies RO metadata into the ro region.
103 // [4] SymbolTable, StringTable, SystemDictionary, and a few other read-only data
104 // are copied into the ro region as read-only tables.
105 // [5] C++ vtables are copied into the md region.
106 // [6] Original class files are copied into the od region.
107 //
108 // The s0/s1 and oa0/oa1 regions are populated inside MetaspaceShared::dump_java_heap_objects.
109 // Their layout is independent of the other 5 regions.
110
111 class DumpRegion {
112 private:
113 const char* _name;
114 char* _base;
115 char* _top;
116 char* _end;
117 bool _is_packed;
118
119 char* expand_top_to(char* newtop) {
120 assert(is_allocatable(), "must be initialized and not packed");
121 assert(newtop >= _top, "must not grow backwards");
122 if (newtop > _end) {
123 MetaspaceShared::report_out_of_space(_name, newtop - _top);
124 ShouldNotReachHere();
125 }
126 MetaspaceShared::commit_shared_space_to(newtop);
127 _top = newtop;
128 return _top;
129 }
130
131 public:
132 DumpRegion(const char* name) : _name(name), _base(NULL), _top(NULL), _end(NULL), _is_packed(false) {}
133
134 char* allocate(size_t num_bytes, size_t alignment=BytesPerWord) {
135 char* p = (char*)align_up(_top, alignment);
136 char* newtop = p + align_up(num_bytes, alignment);
137 expand_top_to(newtop);
138 memset(p, 0, newtop - p);
139 return p;
140 }
141
142 void append_intptr_t(intptr_t n) {
143 assert(is_aligned(_top, sizeof(intptr_t)), "bad alignment");
144 intptr_t *p = (intptr_t*)_top;
145 char* newtop = _top + sizeof(intptr_t);
146 expand_top_to(newtop);
147 *p = n;
148 }
149
150 char* base() const { return _base; }
151 char* top() const { return _top; }
152 char* end() const { return _end; }
153 size_t reserved() const { return _end - _base; }
154 size_t used() const { return _top - _base; }
155 bool is_packed() const { return _is_packed; }
156 bool is_allocatable() const {
157 return !is_packed() && _base != NULL;
158 }
159
160 void print(size_t total_bytes) const {
161 tty->print_cr("%-3s space: " SIZE_FORMAT_W(9) " [ %4.1f%% of total] out of " SIZE_FORMAT_W(9) " bytes [%5.1f%% used] at " INTPTR_FORMAT,
162 _name, used(), percent_of(used(), total_bytes), reserved(), percent_of(used(), reserved()), p2i(_base));
163 }
164 void print_out_of_space_msg(const char* failing_region, size_t needed_bytes) {
165 tty->print("[%-8s] " PTR_FORMAT " - " PTR_FORMAT " capacity =%9d, allocated =%9d",
166 _name, p2i(_base), p2i(_top), int(_end - _base), int(_top - _base));
167 if (strcmp(_name, failing_region) == 0) {
168 tty->print_cr(" required = %d", int(needed_bytes));
169 } else {
170 tty->cr();
171 }
172 }
173
174 void init(const ReservedSpace* rs) {
175 _base = _top = rs->base();
176 _end = rs->end();
177 }
178 void init(char* b, char* t, char* e) {
179 _base = b;
180 _top = t;
181 _end = e;
182 }
183
184 void pack(DumpRegion* next = NULL) {
185 assert(!is_packed(), "sanity");
186 _end = (char*)align_up(_top, Metaspace::reserve_alignment());
187 _is_packed = true;
188 if (next != NULL) {
189 next->_base = next->_top = this->_end;
190 next->_end = MetaspaceShared::shared_rs()->end();
191 }
192 }
193 bool contains(char* p) {
194 return base() <= p && p < top();
195 }
196 };
197
198
199 DumpRegion _mc_region("mc"), _ro_region("ro"), _rw_region("rw"), _md_region("md"), _od_region("od");
200 size_t _total_string_region_size = 0, _total_open_archive_region_size = 0;
201
202 char* MetaspaceShared::misc_code_space_alloc(size_t num_bytes) {
203 return _mc_region.allocate(num_bytes);
204 }
205
206 char* MetaspaceShared::read_only_space_alloc(size_t num_bytes) {
207 return _ro_region.allocate(num_bytes);
208 }
209
210 void MetaspaceShared::initialize_runtime_shared_and_meta_spaces() {
211 assert(UseSharedSpaces, "Must be called when UseSharedSpaces is enabled");
212
213 // If using shared space, open the file that contains the shared space
214 // and map in the memory before initializing the rest of metaspace (so
215 // the addresses don't conflict)
216 address cds_address = NULL;
217 FileMapInfo* mapinfo = new FileMapInfo();
218
219 // Open the shared archive file, read and validate the header. If
220 // initialization fails, shared spaces [UseSharedSpaces] are
221 // disabled and the file is closed.
222 // Map in spaces now also
223 if (mapinfo->initialize() && map_shared_spaces(mapinfo)) {
224 size_t cds_total = core_spaces_size();
225 cds_address = (address)mapinfo->header()->region_addr(0);
226 #ifdef _LP64
227 if (Metaspace::using_class_space()) {
228 char* cds_end = (char*)(cds_address + cds_total);
229 cds_end = (char *)align_up(cds_end, Metaspace::reserve_alignment());
230 // If UseCompressedClassPointers is set then allocate the metaspace area
231 // above the heap and above the CDS area (if it exists).
232 Metaspace::allocate_metaspace_compressed_klass_ptrs(cds_end, cds_address);
233 // map_heap_regions() compares the current narrow oop and klass encodings
234 // with the archived ones, so it must be done after all encodings are determined.
235 mapinfo->map_heap_regions();
236 }
237 #endif // _LP64
238 } else {
239 assert(!mapinfo->is_open() && !UseSharedSpaces,
240 "archive file not closed or shared spaces not disabled.");
241 }
242 }
243
244 void MetaspaceShared::initialize_dumptime_shared_and_meta_spaces() {
245 assert(DumpSharedSpaces, "should be called for dump time only");
246 const size_t reserve_alignment = Metaspace::reserve_alignment();
247 bool large_pages = false; // No large pages when dumping the CDS archive.
248 char* shared_base = (char*)align_up((char*)SharedBaseAddress, reserve_alignment);
249
250 #ifdef _LP64
251 // On 64-bit VM, the heap and class space layout will be the same as if
252 // you're running in -Xshare:on mode:
253 //
254 // +-- SharedBaseAddress (default = 0x800000000)
255 // v
256 // +-..---------+---------+ ... +----+----+----+----+----+---------------+
257 // | Heap | Archive | | MC | RW | RO | MD | OD | class space |
258 // +-..---------+---------+ ... +----+----+----+----+----+---------------+
259 // |<-- MaxHeapSize -->| |<-- UnscaledClassSpaceMax = 4GB ------->|
260 //
261 const uint64_t UnscaledClassSpaceMax = (uint64_t(max_juint) + 1);
262 const size_t cds_total = align_down(UnscaledClassSpaceMax, reserve_alignment);
263 #else
264 // We don't support archives larger than 256MB on 32-bit due to limited virtual address space.
265 size_t cds_total = align_down(256*M, reserve_alignment);
266 #endif
267
268 // First try to reserve the space at the specified SharedBaseAddress.
269 _shared_rs = ReservedSpace(cds_total, reserve_alignment, large_pages, shared_base);
270 if (_shared_rs.is_reserved()) {
271 assert(shared_base == 0 || _shared_rs.base() == shared_base, "should match");
272 } else {
273 // Get a mmap region anywhere if the SharedBaseAddress fails.
274 _shared_rs = ReservedSpace(cds_total, reserve_alignment, large_pages);
275 }
276 if (!_shared_rs.is_reserved()) {
277 vm_exit_during_initialization("Unable to reserve memory for shared space",
278 err_msg(SIZE_FORMAT " bytes.", cds_total));
279 }
280
281 #ifdef _LP64
282 // During dump time, we allocate 4GB (UnscaledClassSpaceMax) of space and split it up:
283 // + The upper 1 GB is used as the "temporary compressed class space" -- preload_classes()
284 // will store Klasses into this space.
285 // + The lower 3 GB is used for the archive -- when preload_classes() is done,
286 // ArchiveCompactor will copy the class metadata into this space, first the RW parts,
287 // then the RO parts.
288
289 assert(UseCompressedOops && UseCompressedClassPointers,
290 "UseCompressedOops and UseCompressedClassPointers must be set");
291
292 size_t max_archive_size = align_down(cds_total * 3 / 4, reserve_alignment);
293 ReservedSpace tmp_class_space = _shared_rs.last_part(max_archive_size);
294 CompressedClassSpaceSize = align_down(tmp_class_space.size(), reserve_alignment);
295 _shared_rs = _shared_rs.first_part(max_archive_size);
296
297 // Set up compress class pointers.
298 Universe::set_narrow_klass_base((address)_shared_rs.base());
299 // Set narrow_klass_shift to be LogKlassAlignmentInBytes. This is consistent
300 // with AOT.
301 Universe::set_narrow_klass_shift(LogKlassAlignmentInBytes);
302
303 Metaspace::initialize_class_space(tmp_class_space);
304 tty->print_cr("narrow_klass_base = " PTR_FORMAT ", narrow_klass_shift = %d",
305 p2i(Universe::narrow_klass_base()), Universe::narrow_klass_shift());
306
307 tty->print_cr("Allocated temporary class space: " SIZE_FORMAT " bytes at " PTR_FORMAT,
308 CompressedClassSpaceSize, p2i(tmp_class_space.base()));
309 #endif
310
311 // Start with 0 committed bytes. The memory will be committed as needed by
312 // MetaspaceShared::commit_shared_space_to().
313 if (!_shared_vs.initialize(_shared_rs, 0)) {
314 vm_exit_during_initialization("Unable to allocate memory for shared space");
315 }
316
317 _mc_region.init(&_shared_rs);
318 tty->print_cr("Allocated shared space: " SIZE_FORMAT " bytes at " PTR_FORMAT,
319 _shared_rs.size(), p2i(_shared_rs.base()));
320 }
321
322 void MetaspaceShared::commit_shared_space_to(char* newtop) {
323 assert(DumpSharedSpaces, "dump-time only");
324 char* base = _shared_rs.base();
325 size_t need_committed_size = newtop - base;
326 size_t has_committed_size = _shared_vs.committed_size();
327 if (need_committed_size < has_committed_size) {
328 return;
329 }
330
331 size_t min_bytes = need_committed_size - has_committed_size;
332 size_t preferred_bytes = 1 * M;
333 size_t uncommitted = _shared_vs.reserved_size() - has_committed_size;
334
335 size_t commit = MAX2(min_bytes, preferred_bytes);
336 assert(commit <= uncommitted, "sanity");
337
338 bool result = _shared_vs.expand_by(commit, false);
339 if (!result) {
340 vm_exit_during_initialization(err_msg("Failed to expand shared space to " SIZE_FORMAT " bytes",
341 need_committed_size));
342 }
343
344 log_info(cds)("Expanding shared spaces by " SIZE_FORMAT_W(7) " bytes [total " SIZE_FORMAT_W(9) " bytes ending at %p]",
345 commit, _shared_vs.actual_committed_size(), _shared_vs.high());
346 }
347
348 // Read/write a data stream for restoring/preserving metadata pointers and
349 // miscellaneous data from/to the shared archive file.
350
351 void MetaspaceShared::serialize(SerializeClosure* soc) {
352 int tag = 0;
353 soc->do_tag(--tag);
354
355 // Verify the sizes of various metadata in the system.
356 soc->do_tag(sizeof(Method));
357 soc->do_tag(sizeof(ConstMethod));
358 soc->do_tag(arrayOopDesc::base_offset_in_bytes(T_BYTE));
359 soc->do_tag(sizeof(ConstantPool));
360 soc->do_tag(sizeof(ConstantPoolCache));
361 soc->do_tag(objArrayOopDesc::base_offset_in_bytes());
362 soc->do_tag(typeArrayOopDesc::base_offset_in_bytes(T_BYTE));
363 soc->do_tag(sizeof(Symbol));
364
365 // Dump/restore miscellaneous metadata.
366 Universe::serialize(soc, true);
367 soc->do_tag(--tag);
368
369 // Dump/restore references to commonly used names and signatures.
370 vmSymbols::serialize(soc);
371 soc->do_tag(--tag);
372
373 // Dump/restore the symbol and string tables
374 SymbolTable::serialize(soc);
375 StringTable::serialize(soc);
376 soc->do_tag(--tag);
377
378 serialize_well_known_classes(soc);
379 soc->do_tag(--tag);
380
381 soc->do_tag(666);
382 }
383
384 void MetaspaceShared::serialize_well_known_classes(SerializeClosure* soc) {
385 java_lang_Class::serialize(soc);
386 java_lang_String::serialize(soc);
387 java_lang_System::serialize(soc);
388 java_lang_ClassLoader::serialize(soc);
389 java_lang_Throwable::serialize(soc);
390 java_lang_Thread::serialize(soc);
391 java_lang_ThreadGroup::serialize(soc);
392 java_lang_AssertionStatusDirectives::serialize(soc);
393 java_lang_ref_SoftReference::serialize(soc);
394 java_lang_invoke_MethodHandle::serialize(soc);
395 java_lang_invoke_DirectMethodHandle::serialize(soc);
396 java_lang_invoke_MemberName::serialize(soc);
397 java_lang_invoke_ResolvedMethodName::serialize(soc);
398 java_lang_invoke_LambdaForm::serialize(soc);
399 java_lang_invoke_MethodType::serialize(soc);
400 java_lang_invoke_CallSite::serialize(soc);
401 java_lang_invoke_MethodHandleNatives_CallSiteContext::serialize(soc);
402 java_security_AccessControlContext::serialize(soc);
403 java_lang_reflect_AccessibleObject::serialize(soc);
404 java_lang_reflect_Method::serialize(soc);
405 java_lang_reflect_Constructor::serialize(soc);
406 java_lang_reflect_Field::serialize(soc);
407 java_nio_Buffer::serialize(soc);
408 reflect_ConstantPool::serialize(soc);
409 reflect_UnsafeStaticFieldAccessorImpl::serialize(soc);
410 java_lang_reflect_Parameter::serialize(soc);
411 java_lang_Module::serialize(soc);
412 java_lang_StackTraceElement::serialize(soc);
413 java_lang_StackFrameInfo::serialize(soc);
414 java_lang_LiveStackFrameInfo::serialize(soc);
415 }
416
417 address MetaspaceShared::cds_i2i_entry_code_buffers(size_t total_size) {
418 if (DumpSharedSpaces) {
419 if (_cds_i2i_entry_code_buffers == NULL) {
420 _cds_i2i_entry_code_buffers = (address)misc_code_space_alloc(total_size);
421 _cds_i2i_entry_code_buffers_size = total_size;
422 }
423 } else if (UseSharedSpaces) {
424 assert(_cds_i2i_entry_code_buffers != NULL, "must already been initialized");
425 } else {
426 return NULL;
427 }
428
429 assert(_cds_i2i_entry_code_buffers_size == total_size, "must not change");
430 return _cds_i2i_entry_code_buffers;
431 }
432
433 // CDS code for dumping shared archive.
434
435 // Global object for holding classes that have been loaded. Since this
436 // is run at a safepoint just before exit, this is the entire set of classes.
437 static GrowableArray<Klass*>* _global_klass_objects;
438
439 static void collect_array_classes(Klass* k) {
440 _global_klass_objects->append_if_missing(k);
441 if (k->is_array_klass()) {
442 // Add in the array classes too
443 ArrayKlass* ak = ArrayKlass::cast(k);
444 Klass* h = ak->higher_dimension();
445 if (h != NULL) {
446 h->array_klasses_do(collect_array_classes);
447 }
448 }
449 }
450
451 class CollectClassesClosure : public KlassClosure {
452 void do_klass(Klass* k) {
453 if (!UseAppCDS && !k->class_loader_data()->is_the_null_class_loader_data()) {
454 // AppCDS is not enabled. Let's omit non-boot classes.
455 return;
456 }
457
458 if (!(k->is_instance_klass() && InstanceKlass::cast(k)->is_in_error_state())) {
459 if (k->is_instance_klass() && InstanceKlass::cast(k)->signers() != NULL) {
460 // Mark any class with signers and don't add to the _global_klass_objects
461 k->set_has_signer_and_not_archived();
462 } else {
463 _global_klass_objects->append_if_missing(k);
464 }
465 }
466 if (k->is_array_klass()) {
467 // Add in the array classes too
468 ArrayKlass* ak = ArrayKlass::cast(k);
469 Klass* h = ak->higher_dimension();
470 if (h != NULL) {
471 h->array_klasses_do(collect_array_classes);
472 }
473 }
474 }
475 };
476
477 static void remove_unshareable_in_classes() {
478 for (int i = 0; i < _global_klass_objects->length(); i++) {
479 Klass* k = _global_klass_objects->at(i);
480 if (!k->is_objArray_klass()) {
481 // InstanceKlass and TypeArrayKlass will in turn call remove_unshareable_info
482 // on their array classes.
483 assert(k->is_instance_klass() || k->is_typeArray_klass(), "must be");
484 k->remove_unshareable_info();
485 }
486 }
487 }
488
489 static void remove_java_mirror_in_classes() {
490 for (int i = 0; i < _global_klass_objects->length(); i++) {
491 Klass* k = _global_klass_objects->at(i);
492 if (!k->is_objArray_klass()) {
493 // InstanceKlass and TypeArrayKlass will in turn call remove_unshareable_info
494 // on their array classes.
495 assert(k->is_instance_klass() || k->is_typeArray_klass(), "must be");
496 k->remove_java_mirror();
497 }
498 }
499 }
500
501 static void clear_basic_type_mirrors() {
502 assert(!MetaspaceShared::is_heap_object_archiving_allowed(), "Sanity");
503 Universe::set_int_mirror(NULL);
504 Universe::set_float_mirror(NULL);
505 Universe::set_double_mirror(NULL);
506 Universe::set_byte_mirror(NULL);
507 Universe::set_bool_mirror(NULL);
508 Universe::set_char_mirror(NULL);
509 Universe::set_long_mirror(NULL);
510 Universe::set_short_mirror(NULL);
511 Universe::set_void_mirror(NULL);
512 }
513
514 static void rewrite_nofast_bytecode(Method* method) {
515 BytecodeStream bcs(method);
516 while (!bcs.is_last_bytecode()) {
517 Bytecodes::Code opcode = bcs.next();
518 switch (opcode) {
519 case Bytecodes::_getfield: *bcs.bcp() = Bytecodes::_nofast_getfield; break;
520 case Bytecodes::_putfield: *bcs.bcp() = Bytecodes::_nofast_putfield; break;
521 case Bytecodes::_aload_0: *bcs.bcp() = Bytecodes::_nofast_aload_0; break;
522 case Bytecodes::_iload: {
523 if (!bcs.is_wide()) {
524 *bcs.bcp() = Bytecodes::_nofast_iload;
525 }
526 break;
527 }
528 default: break;
529 }
530 }
531 }
532
533 // Walk all methods in the class list to ensure that they won't be modified at
534 // run time. This includes:
535 // [1] Rewrite all bytecodes as needed, so that the ConstMethod* will not be modified
536 // at run time by RewriteBytecodes/RewriteFrequentPairs
537 // [2] Assign a fingerprint, so one doesn't need to be assigned at run-time.
538 static void rewrite_nofast_bytecodes_and_calculate_fingerprints() {
539 for (int i = 0; i < _global_klass_objects->length(); i++) {
540 Klass* k = _global_klass_objects->at(i);
541 if (k->is_instance_klass()) {
542 InstanceKlass* ik = InstanceKlass::cast(k);
543 for (int i = 0; i < ik->methods()->length(); i++) {
544 Method* m = ik->methods()->at(i);
545 rewrite_nofast_bytecode(m);
546 Fingerprinter fp(m);
547 // The side effect of this call sets method's fingerprint field.
548 fp.fingerprint();
549 }
550 }
551 }
552 }
553
554 static void relocate_cached_class_file() {
555 for (int i = 0; i < _global_klass_objects->length(); i++) {
556 Klass* k = _global_klass_objects->at(i);
557 if (k->is_instance_klass()) {
558 InstanceKlass* ik = InstanceKlass::cast(k);
559 JvmtiCachedClassFileData* p = ik->get_archived_class_data();
560 if (p != NULL) {
561 int size = offset_of(JvmtiCachedClassFileData, data) + p->length;
562 JvmtiCachedClassFileData* q = (JvmtiCachedClassFileData*)_od_region.allocate(size);
563 q->length = p->length;
564 memcpy(q->data, p->data, p->length);
565 ik->set_archived_class_data(q);
566 }
567 }
568 }
569 }
570
571 NOT_PRODUCT(
572 static void assert_not_anonymous_class(InstanceKlass* k) {
573 assert(!(k->is_anonymous()), "cannot archive anonymous classes");
574 }
575
576 // Anonymous classes are not stored inside any dictionaries. They are created by
577 // SystemDictionary::parse_stream() with a non-null host_klass.
578 static void assert_no_anonymoys_classes_in_dictionaries() {
579 ClassLoaderDataGraph::dictionary_classes_do(assert_not_anonymous_class);
580 })
581
582 // Objects of the Metadata types (such as Klass and ConstantPool) have C++ vtables.
583 // (In GCC this is the field <Type>::_vptr, i.e., first word in the object.)
584 //
585 // Addresses of the vtables and the methods may be different across JVM runs,
586 // if libjvm.so is dynamically loaded at a different base address.
587 //
588 // To ensure that the Metadata objects in the CDS archive always have the correct vtable:
589 //
590 // + at dump time: we redirect the _vptr to point to our own vtables inside
591 // the CDS image
592 // + at run time: we clone the actual contents of the vtables from libjvm.so
593 // into our own tables.
594
595 // Currently, the archive contain ONLY the following types of objects that have C++ vtables.
596 #define CPP_VTABLE_PATCH_TYPES_DO(f) \
597 f(ConstantPool) \
598 f(InstanceKlass) \
599 f(InstanceClassLoaderKlass) \
600 f(InstanceMirrorKlass) \
601 f(InstanceRefKlass) \
602 f(Method) \
603 f(ObjArrayKlass) \
604 f(TypeArrayKlass)
605
606 class CppVtableInfo {
607 intptr_t _vtable_size;
608 intptr_t _cloned_vtable[1];
609 public:
610 static int num_slots(int vtable_size) {
611 return 1 + vtable_size; // Need to add the space occupied by _vtable_size;
612 }
613 int vtable_size() { return int(uintx(_vtable_size)); }
614 void set_vtable_size(int n) { _vtable_size = intptr_t(n); }
615 intptr_t* cloned_vtable() { return &_cloned_vtable[0]; }
616 void zero() { memset(_cloned_vtable, 0, sizeof(intptr_t) * vtable_size()); }
617 // Returns the address of the next CppVtableInfo that can be placed immediately after this CppVtableInfo
618 static size_t byte_size(int vtable_size) {
619 CppVtableInfo i;
620 return pointer_delta(&i._cloned_vtable[vtable_size], &i, sizeof(u1));
621 }
622 };
623
624 template <class T> class CppVtableCloner : public T {
625 static intptr_t* vtable_of(Metadata& m) {
626 return *((intptr_t**)&m);
627 }
628 static CppVtableInfo* _info;
629
630 static int get_vtable_length(const char* name);
631
632 public:
633 // Allocate and initialize the C++ vtable, starting from top, but do not go past end.
634 static intptr_t* allocate(const char* name);
635
636 // Clone the vtable to ...
637 static intptr_t* clone_vtable(const char* name, CppVtableInfo* info);
638
639 static void zero_vtable_clone() {
640 assert(DumpSharedSpaces, "dump-time only");
641 _info->zero();
642 }
643
644 // Switch the vtable pointer to point to the cloned vtable.
645 static void patch(Metadata* obj) {
646 assert(DumpSharedSpaces, "dump-time only");
647 *(void**)obj = (void*)(_info->cloned_vtable());
648 }
649
650 static bool is_valid_shared_object(const T* obj) {
651 intptr_t* vptr = *(intptr_t**)obj;
652 return vptr == _info->cloned_vtable();
653 }
654 };
655
656 template <class T> CppVtableInfo* CppVtableCloner<T>::_info = NULL;
657
658 template <class T>
659 intptr_t* CppVtableCloner<T>::allocate(const char* name) {
660 assert(is_aligned(_md_region.top(), sizeof(intptr_t)), "bad alignment");
661 int n = get_vtable_length(name);
662 _info = (CppVtableInfo*)_md_region.allocate(CppVtableInfo::byte_size(n), sizeof(intptr_t));
663 _info->set_vtable_size(n);
664
665 intptr_t* p = clone_vtable(name, _info);
666 assert((char*)p == _md_region.top(), "must be");
667
668 return p;
669 }
670
671 template <class T>
672 intptr_t* CppVtableCloner<T>::clone_vtable(const char* name, CppVtableInfo* info) {
673 if (!DumpSharedSpaces) {
674 assert(_info == 0, "_info is initialized only at dump time");
675 _info = info; // Remember it -- it will be used by MetaspaceShared::is_valid_shared_method()
676 }
677 T tmp; // Allocate temporary dummy metadata object to get to the original vtable.
678 int n = info->vtable_size();
679 intptr_t* srcvtable = vtable_of(tmp);
680 intptr_t* dstvtable = info->cloned_vtable();
681
682 // We already checked (and, if necessary, adjusted n) when the vtables were allocated, so we are
683 // safe to do memcpy.
684 log_debug(cds, vtables)("Copying %3d vtable entries for %s", n, name);
685 memcpy(dstvtable, srcvtable, sizeof(intptr_t) * n);
686 return dstvtable + n;
687 }
688
689 // To determine the size of the vtable for each type, we use the following
690 // trick by declaring 2 subclasses:
691 //
692 // class CppVtableTesterA: public InstanceKlass {virtual int last_virtual_method() {return 1;} };
693 // class CppVtableTesterB: public InstanceKlass {virtual void* last_virtual_method() {return NULL}; };
694 //
695 // CppVtableTesterA and CppVtableTesterB's vtables have the following properties:
696 // - Their size (N+1) is exactly one more than the size of InstanceKlass's vtable (N)
697 // - The first N entries have are exactly the same as in InstanceKlass's vtable.
698 // - Their last entry is different.
699 //
700 // So to determine the value of N, we just walk CppVtableTesterA and CppVtableTesterB's tables
701 // and find the first entry that's different.
702 //
703 // This works on all C++ compilers supported by Oracle, but you may need to tweak it for more
704 // esoteric compilers.
705
706 template <class T> class CppVtableTesterB: public T {
707 public:
708 virtual int last_virtual_method() {return 1;}
709 };
710
711 template <class T> class CppVtableTesterA : public T {
712 public:
713 virtual void* last_virtual_method() {
714 // Make this different than CppVtableTesterB::last_virtual_method so the C++
715 // compiler/linker won't alias the two functions.
716 return NULL;
717 }
718 };
719
720 template <class T>
721 int CppVtableCloner<T>::get_vtable_length(const char* name) {
722 CppVtableTesterA<T> a;
723 CppVtableTesterB<T> b;
724
725 intptr_t* avtable = vtable_of(a);
726 intptr_t* bvtable = vtable_of(b);
727
728 // Start at slot 1, because slot 0 may be RTTI (on Solaris/Sparc)
729 int vtable_len = 1;
730 for (; ; vtable_len++) {
731 if (avtable[vtable_len] != bvtable[vtable_len]) {
732 break;
733 }
734 }
735 log_debug(cds, vtables)("Found %3d vtable entries for %s", vtable_len, name);
736
737 return vtable_len;
738 }
739
740 #define ALLOC_CPP_VTABLE_CLONE(c) \
741 CppVtableCloner<c>::allocate(#c);
742
743 #define CLONE_CPP_VTABLE(c) \
744 p = CppVtableCloner<c>::clone_vtable(#c, (CppVtableInfo*)p);
745
746 #define ZERO_CPP_VTABLE(c) \
747 CppVtableCloner<c>::zero_vtable_clone();
748
749 // This can be called at both dump time and run time.
750 intptr_t* MetaspaceShared::clone_cpp_vtables(intptr_t* p) {
751 assert(DumpSharedSpaces || UseSharedSpaces, "sanity");
752 CPP_VTABLE_PATCH_TYPES_DO(CLONE_CPP_VTABLE);
753 return p;
754 }
755
756 void MetaspaceShared::zero_cpp_vtable_clones_for_writing() {
757 assert(DumpSharedSpaces, "dump-time only");
758 CPP_VTABLE_PATCH_TYPES_DO(ZERO_CPP_VTABLE);
759 }
760
761 // Allocate and initialize the C++ vtables, starting from top, but do not go past end.
762 void MetaspaceShared::allocate_cpp_vtable_clones() {
763 assert(DumpSharedSpaces, "dump-time only");
764 // Layout (each slot is a intptr_t):
765 // [number of slots in the first vtable = n1]
766 // [ <n1> slots for the first vtable]
767 // [number of slots in the first second = n2]
768 // [ <n2> slots for the second vtable]
769 // ...
770 // The order of the vtables is the same as the CPP_VTAB_PATCH_TYPES_DO macro.
771 CPP_VTABLE_PATCH_TYPES_DO(ALLOC_CPP_VTABLE_CLONE);
772 }
773
774 // Switch the vtable pointer to point to the cloned vtable. We assume the
775 // vtable pointer is in first slot in object.
776 void MetaspaceShared::patch_cpp_vtable_pointers() {
777 int n = _global_klass_objects->length();
778 for (int i = 0; i < n; i++) {
779 Klass* obj = _global_klass_objects->at(i);
780 if (obj->is_instance_klass()) {
781 InstanceKlass* ik = InstanceKlass::cast(obj);
782 if (ik->is_class_loader_instance_klass()) {
783 CppVtableCloner<InstanceClassLoaderKlass>::patch(ik);
784 } else if (ik->is_reference_instance_klass()) {
785 CppVtableCloner<InstanceRefKlass>::patch(ik);
786 } else if (ik->is_mirror_instance_klass()) {
787 CppVtableCloner<InstanceMirrorKlass>::patch(ik);
788 } else {
789 CppVtableCloner<InstanceKlass>::patch(ik);
790 }
791 ConstantPool* cp = ik->constants();
792 CppVtableCloner<ConstantPool>::patch(cp);
793 for (int j = 0; j < ik->methods()->length(); j++) {
794 Method* m = ik->methods()->at(j);
795 CppVtableCloner<Method>::patch(m);
796 assert(CppVtableCloner<Method>::is_valid_shared_object(m), "must be");
797 }
798 } else if (obj->is_objArray_klass()) {
799 CppVtableCloner<ObjArrayKlass>::patch(obj);
800 } else {
801 assert(obj->is_typeArray_klass(), "sanity");
802 CppVtableCloner<TypeArrayKlass>::patch(obj);
803 }
804 }
805 }
806
807 bool MetaspaceShared::is_valid_shared_method(const Method* m) {
808 assert(is_in_shared_metaspace(m), "must be");
809 return CppVtableCloner<Method>::is_valid_shared_object(m);
810 }
811
812 // Closure for serializing initialization data out to a data area to be
813 // written to the shared file.
814
815 class WriteClosure : public SerializeClosure {
816 private:
817 DumpRegion* _dump_region;
818
819 public:
820 WriteClosure(DumpRegion* r) {
821 _dump_region = r;
822 }
823
824 void do_ptr(void** p) {
825 _dump_region->append_intptr_t((intptr_t)*p);
826 }
827
828 void do_u4(u4* p) {
829 void* ptr = (void*)(uintx(*p));
830 do_ptr(&ptr);
831 }
832
833 void do_tag(int tag) {
834 _dump_region->append_intptr_t((intptr_t)tag);
835 }
836
837 void do_oop(oop* o) {
838 if (*o == NULL) {
839 _dump_region->append_intptr_t(0);
840 } else {
841 assert(MetaspaceShared::is_heap_object_archiving_allowed(),
842 "Archiving heap object is not allowed");
843 _dump_region->append_intptr_t(
844 (intptr_t)oopDesc::encode_heap_oop_not_null(*o));
845 }
846 }
847
848 void do_region(u_char* start, size_t size) {
849 assert((intptr_t)start % sizeof(intptr_t) == 0, "bad alignment");
850 assert(size % sizeof(intptr_t) == 0, "bad size");
851 do_tag((int)size);
852 while (size > 0) {
853 _dump_region->append_intptr_t(*(intptr_t*)start);
854 start += sizeof(intptr_t);
855 size -= sizeof(intptr_t);
856 }
857 }
858
859 bool reading() const { return false; }
860 };
861
862 // This is for dumping detailed statistics for the allocations
863 // in the shared spaces.
864 class DumpAllocStats : public ResourceObj {
865 public:
866
867 // Here's poor man's enum inheritance
868 #define SHAREDSPACE_OBJ_TYPES_DO(f) \
869 METASPACE_OBJ_TYPES_DO(f) \
870 f(SymbolHashentry) \
871 f(SymbolBucket) \
872 f(StringHashentry) \
873 f(StringBucket) \
874 f(Other)
875
876 enum Type {
877 // Types are MetaspaceObj::ClassType, MetaspaceObj::SymbolType, etc
878 SHAREDSPACE_OBJ_TYPES_DO(METASPACE_OBJ_TYPE_DECLARE)
879 _number_of_types
880 };
881
882 static const char * type_name(Type type) {
883 switch(type) {
884 SHAREDSPACE_OBJ_TYPES_DO(METASPACE_OBJ_TYPE_NAME_CASE)
885 default:
886 ShouldNotReachHere();
887 return NULL;
888 }
889 }
890
891 public:
892 enum { RO = 0, RW = 1 };
893
894 int _counts[2][_number_of_types];
895 int _bytes [2][_number_of_types];
896
897 DumpAllocStats() {
898 memset(_counts, 0, sizeof(_counts));
899 memset(_bytes, 0, sizeof(_bytes));
900 };
901
902 void record(MetaspaceObj::Type type, int byte_size, bool read_only) {
903 assert(int(type) >= 0 && type < MetaspaceObj::_number_of_types, "sanity");
904 int which = (read_only) ? RO : RW;
905 _counts[which][type] ++;
906 _bytes [which][type] += byte_size;
907 }
908
909 void record_other_type(int byte_size, bool read_only) {
910 int which = (read_only) ? RO : RW;
911 _bytes [which][OtherType] += byte_size;
912 }
913 void print_stats(int ro_all, int rw_all, int mc_all, int md_all);
914 };
915
916 void DumpAllocStats::print_stats(int ro_all, int rw_all, int mc_all, int md_all) {
917 // Calculate size of data that was not allocated by Metaspace::allocate()
918 MetaspaceSharedStats *stats = MetaspaceShared::stats();
919
920 // symbols
921 _counts[RO][SymbolHashentryType] = stats->symbol.hashentry_count;
922 _bytes [RO][SymbolHashentryType] = stats->symbol.hashentry_bytes;
923
924 _counts[RO][SymbolBucketType] = stats->symbol.bucket_count;
925 _bytes [RO][SymbolBucketType] = stats->symbol.bucket_bytes;
926
927 // strings
928 _counts[RO][StringHashentryType] = stats->string.hashentry_count;
929 _bytes [RO][StringHashentryType] = stats->string.hashentry_bytes;
930
931 _counts[RO][StringBucketType] = stats->string.bucket_count;
932 _bytes [RO][StringBucketType] = stats->string.bucket_bytes;
933
934 // TODO: count things like dictionary, vtable, etc
935 _bytes[RW][OtherType] += mc_all + md_all;
936 rw_all += mc_all + md_all; // mc/md are mapped Read/Write
937
938 // prevent divide-by-zero
939 if (ro_all < 1) {
940 ro_all = 1;
941 }
942 if (rw_all < 1) {
943 rw_all = 1;
944 }
945
946 int all_ro_count = 0;
947 int all_ro_bytes = 0;
948 int all_rw_count = 0;
949 int all_rw_bytes = 0;
950
951 // To make fmt_stats be a syntactic constant (for format warnings), use #define.
952 #define fmt_stats "%-20s: %8d %10d %5.1f | %8d %10d %5.1f | %8d %10d %5.1f"
953 const char *sep = "--------------------+---------------------------+---------------------------+--------------------------";
954 const char *hdr = " ro_cnt ro_bytes % | rw_cnt rw_bytes % | all_cnt all_bytes %";
955
956 LogMessage(cds) msg;
957
958 msg.info("Detailed metadata info (excluding od/st regions; rw stats include md/mc regions):");
959 msg.info("%s", hdr);
960 msg.info("%s", sep);
961 for (int type = 0; type < int(_number_of_types); type ++) {
962 const char *name = type_name((Type)type);
963 int ro_count = _counts[RO][type];
964 int ro_bytes = _bytes [RO][type];
965 int rw_count = _counts[RW][type];
966 int rw_bytes = _bytes [RW][type];
967 int count = ro_count + rw_count;
968 int bytes = ro_bytes + rw_bytes;
969
970 double ro_perc = percent_of(ro_bytes, ro_all);
971 double rw_perc = percent_of(rw_bytes, rw_all);
972 double perc = percent_of(bytes, ro_all + rw_all);
973
974 msg.info(fmt_stats, name,
975 ro_count, ro_bytes, ro_perc,
976 rw_count, rw_bytes, rw_perc,
977 count, bytes, perc);
978
979 all_ro_count += ro_count;
980 all_ro_bytes += ro_bytes;
981 all_rw_count += rw_count;
982 all_rw_bytes += rw_bytes;
983 }
984
985 int all_count = all_ro_count + all_rw_count;
986 int all_bytes = all_ro_bytes + all_rw_bytes;
987
988 double all_ro_perc = percent_of(all_ro_bytes, ro_all);
989 double all_rw_perc = percent_of(all_rw_bytes, rw_all);
990 double all_perc = percent_of(all_bytes, ro_all + rw_all);
991
992 msg.info("%s", sep);
993 msg.info(fmt_stats, "Total",
994 all_ro_count, all_ro_bytes, all_ro_perc,
995 all_rw_count, all_rw_bytes, all_rw_perc,
996 all_count, all_bytes, all_perc);
997
998 assert(all_ro_bytes == ro_all, "everything should have been counted");
999 assert(all_rw_bytes == rw_all, "everything should have been counted");
1000
1001 #undef fmt_stats
1002 }
1003
1004 // Populate the shared space.
1005
1006 class VM_PopulateDumpSharedSpace: public VM_Operation {
1007 private:
1008 GrowableArray<MemRegion> *_closed_archive_heap_regions;
1009 GrowableArray<MemRegion> *_open_archive_heap_regions;
1010
1011 void dump_java_heap_objects() NOT_CDS_JAVA_HEAP_RETURN;
1012 void dump_symbols();
1013 char* dump_read_only_tables();
1014 void print_region_stats();
1015 void print_heap_region_stats(GrowableArray<MemRegion> *heap_mem,
1016 const char *name, const size_t total_size);
1017 public:
1018
1019 VMOp_Type type() const { return VMOp_PopulateDumpSharedSpace; }
1020 void doit(); // outline because gdb sucks
1021 static void write_region(FileMapInfo* mapinfo, int region, DumpRegion* space, bool read_only, bool allow_exec);
1022 bool allow_nested_vm_operations() const { return true; }
1023 }; // class VM_PopulateDumpSharedSpace
1024
1025 class SortedSymbolClosure: public SymbolClosure {
1026 GrowableArray<Symbol*> _symbols;
1027 virtual void do_symbol(Symbol** sym) {
1028 assert((*sym)->is_permanent(), "archived symbols must be permanent");
1029 _symbols.append(*sym);
1030 }
1031 static int compare_symbols_by_address(Symbol** a, Symbol** b) {
1032 if (a[0] < b[0]) {
1033 return -1;
1034 } else if (a[0] == b[0]) {
1035 return 0;
1036 } else {
1037 return 1;
1038 }
1039 }
1040
1041 public:
1042 SortedSymbolClosure() {
1043 SymbolTable::symbols_do(this);
1044 _symbols.sort(compare_symbols_by_address);
1045 }
1046 GrowableArray<Symbol*>* get_sorted_symbols() {
1047 return &_symbols;
1048 }
1049 };
1050
1051 // ArchiveCompactor --
1052 //
1053 // This class is the central piece of shared archive compaction -- all metaspace data are
1054 // initially allocated outside of the shared regions. ArchiveCompactor copies the
1055 // metaspace data into their final location in the shared regions.
1056
1057 class ArchiveCompactor : AllStatic {
1058 static DumpAllocStats* _alloc_stats;
1059 static SortedSymbolClosure* _ssc;
1060
1061 static unsigned my_hash(const address& a) {
1062 return primitive_hash<address>(a);
1063 }
1064 static bool my_equals(const address& a0, const address& a1) {
1065 return primitive_equals<address>(a0, a1);
1066 }
1067 typedef ResourceHashtable<
1068 address, address,
1069 ArchiveCompactor::my_hash, // solaris compiler doesn't like: primitive_hash<address>
1070 ArchiveCompactor::my_equals, // solaris compiler doesn't like: primitive_equals<address>
1071 16384, ResourceObj::C_HEAP> RelocationTable;
1072 static RelocationTable* _new_loc_table;
1073
1074 public:
1075 static void initialize() {
1076 _alloc_stats = new(ResourceObj::C_HEAP, mtInternal)DumpAllocStats;
1077 _new_loc_table = new(ResourceObj::C_HEAP, mtInternal)RelocationTable;
1078 }
1079 static DumpAllocStats* alloc_stats() {
1080 return _alloc_stats;
1081 }
1082
1083 static void allocate(MetaspaceClosure::Ref* ref, bool read_only) {
1084 address obj = ref->obj();
1085 int bytes = ref->size() * BytesPerWord;
1086 char* p;
1087 size_t alignment = BytesPerWord;
1088 char* oldtop;
1089 char* newtop;
1090
1091 if (read_only) {
1092 oldtop = _ro_region.top();
1093 p = _ro_region.allocate(bytes, alignment);
1094 newtop = _ro_region.top();
1095 } else {
1096 oldtop = _rw_region.top();
1097 p = _rw_region.allocate(bytes, alignment);
1098 newtop = _rw_region.top();
1099 }
1100 memcpy(p, obj, bytes);
1101 bool isnew = _new_loc_table->put(obj, (address)p);
1102 log_trace(cds)("Copy: " PTR_FORMAT " ==> " PTR_FORMAT " %d", p2i(obj), p2i(p), bytes);
1103 assert(isnew, "must be");
1104
1105 _alloc_stats->record(ref->msotype(), int(newtop - oldtop), read_only);
1106 if (ref->msotype() == MetaspaceObj::SymbolType) {
1107 uintx delta = MetaspaceShared::object_delta(p);
1108 if (delta > MAX_SHARED_DELTA) {
1109 // This is just a sanity check and should not appear in any real world usage. This
1110 // happens only if you allocate more than 2GB of Symbols and would require
1111 // millions of shared classes.
1112 vm_exit_during_initialization("Too many Symbols in the CDS archive",
1113 "Please reduce the number of shared classes.");
1114 }
1115 }
1116 }
1117
1118 static address get_new_loc(MetaspaceClosure::Ref* ref) {
1119 address* pp = _new_loc_table->get(ref->obj());
1120 assert(pp != NULL, "must be");
1121 return *pp;
1122 }
1123
1124 private:
1125 // Makes a shallow copy of visited MetaspaceObj's
1126 class ShallowCopier: public UniqueMetaspaceClosure {
1127 bool _read_only;
1128 public:
1129 ShallowCopier(bool read_only) : _read_only(read_only) {}
1130
1131 virtual void do_unique_ref(Ref* ref, bool read_only) {
1132 if (read_only == _read_only) {
1133 allocate(ref, read_only);
1134 }
1135 }
1136 };
1137
1138 // Relocate embedded pointers within a MetaspaceObj's shallow copy
1139 class ShallowCopyEmbeddedRefRelocator: public UniqueMetaspaceClosure {
1140 public:
1141 virtual void do_unique_ref(Ref* ref, bool read_only) {
1142 address new_loc = get_new_loc(ref);
1143 RefRelocator refer;
1144 ref->metaspace_pointers_do_at(&refer, new_loc);
1145 }
1146 };
1147
1148 // Relocate a reference to point to its shallow copy
1149 class RefRelocator: public MetaspaceClosure {
1150 public:
1151 virtual bool do_ref(Ref* ref, bool read_only) {
1152 if (ref->not_null()) {
1153 ref->update(get_new_loc(ref));
1154 }
1155 return false; // Do not recurse.
1156 }
1157 };
1158
1159 #ifdef ASSERT
1160 class IsRefInArchiveChecker: public MetaspaceClosure {
1161 public:
1162 virtual bool do_ref(Ref* ref, bool read_only) {
1163 if (ref->not_null()) {
1164 char* obj = (char*)ref->obj();
1165 assert(_ro_region.contains(obj) || _rw_region.contains(obj),
1166 "must be relocated to point to CDS archive");
1167 }
1168 return false; // Do not recurse.
1169 }
1170 };
1171 #endif
1172
1173 public:
1174 static void copy_and_compact() {
1175 // We should no longer allocate anything from the metaspace, so that
1176 // we can have a stable set of MetaspaceObjs to work with.
1177 Metaspace::freeze();
1178
1179 ResourceMark rm;
1180 SortedSymbolClosure the_ssc; // StackObj
1181 _ssc = &the_ssc;
1182
1183 tty->print_cr("Scanning all metaspace objects ... ");
1184 {
1185 // allocate and shallow-copy RW objects, immediately following the MC region
1186 tty->print_cr("Allocating RW objects ... ");
1187 _mc_region.pack(&_rw_region);
1188
1189 ResourceMark rm;
1190 ShallowCopier rw_copier(false);
1191 iterate_roots(&rw_copier);
1192 }
1193 {
1194 // allocate and shallow-copy of RO object, immediately following the RW region
1195 tty->print_cr("Allocating RO objects ... ");
1196 _rw_region.pack(&_ro_region);
1197
1198 ResourceMark rm;
1199 ShallowCopier ro_copier(true);
1200 iterate_roots(&ro_copier);
1201 }
1202 {
1203 tty->print_cr("Relocating embedded pointers ... ");
1204 ResourceMark rm;
1205 ShallowCopyEmbeddedRefRelocator emb_reloc;
1206 iterate_roots(&emb_reloc);
1207 }
1208 {
1209 tty->print_cr("Relocating external roots ... ");
1210 ResourceMark rm;
1211 RefRelocator ext_reloc;
1212 iterate_roots(&ext_reloc);
1213 }
1214
1215 #ifdef ASSERT
1216 {
1217 tty->print_cr("Verifying external roots ... ");
1218 ResourceMark rm;
1219 IsRefInArchiveChecker checker;
1220 iterate_roots(&checker);
1221 }
1222 #endif
1223
1224
1225 // cleanup
1226 _ssc = NULL;
1227 }
1228
1229 // We must relocate the System::_well_known_klasses only after we have copied the
1230 // java objects in during dump_java_heap_objects(): during the object copy, we operate on
1231 // old objects which assert that their klass is the original klass.
1232 static void relocate_well_known_klasses() {
1233 {
1234 tty->print_cr("Relocating SystemDictionary::_well_known_klasses[] ... ");
1235 ResourceMark rm;
1236 RefRelocator ext_reloc;
1237 SystemDictionary::well_known_klasses_do(&ext_reloc);
1238 }
1239 // NOTE: after this point, we shouldn't have any globals that can reach the old
1240 // objects.
1241
1242 // We cannot use any of the objects in the heap anymore (except for the objects
1243 // in the CDS shared string regions) because their headers no longer point to
1244 // valid Klasses.
1245 }
1246
1247 static void iterate_roots(MetaspaceClosure* it) {
1248 GrowableArray<Symbol*>* symbols = _ssc->get_sorted_symbols();
1249 for (int i=0; i<symbols->length(); i++) {
1250 it->push(symbols->adr_at(i));
1251 }
1252 if (_global_klass_objects != NULL) {
1253 // Need to fix up the pointers
1254 for (int i = 0; i < _global_klass_objects->length(); i++) {
1255 // NOTE -- this requires that the vtable is NOT yet patched, or else we are hosed.
1256 it->push(_global_klass_objects->adr_at(i));
1257 }
1258 }
1259 FileMapInfo::metaspace_pointers_do(it);
1260 SystemDictionary::classes_do(it);
1261 Universe::metaspace_pointers_do(it);
1262 SymbolTable::metaspace_pointers_do(it);
1263 vmSymbols::metaspace_pointers_do(it);
1264 }
1265
1266 static Klass* get_relocated_klass(Klass* orig_klass) {
1267 assert(DumpSharedSpaces, "dump time only");
1268 address* pp = _new_loc_table->get((address)orig_klass);
1269 assert(pp != NULL, "must be");
1270 Klass* klass = (Klass*)(*pp);
1271 assert(klass->is_klass(), "must be");
1272 return klass;
1273 }
1274 };
1275
1276 DumpAllocStats* ArchiveCompactor::_alloc_stats;
1277 SortedSymbolClosure* ArchiveCompactor::_ssc;
1278 ArchiveCompactor::RelocationTable* ArchiveCompactor::_new_loc_table;
1279
1280 void VM_PopulateDumpSharedSpace::write_region(FileMapInfo* mapinfo, int region_idx,
1281 DumpRegion* dump_region, bool read_only, bool allow_exec) {
1282 mapinfo->write_region(region_idx, dump_region->base(), dump_region->used(), read_only, allow_exec);
1283 }
1284
1285 void VM_PopulateDumpSharedSpace::dump_symbols() {
1286 tty->print_cr("Dumping symbol table ...");
1287
1288 NOT_PRODUCT(SymbolTable::verify());
1289 SymbolTable::write_to_archive();
1290 }
1291
1292 char* VM_PopulateDumpSharedSpace::dump_read_only_tables() {
1293 char* oldtop = _ro_region.top();
1294 // Reorder the system dictionary. Moving the symbols affects
1295 // how the hash table indices are calculated.
1296 SystemDictionary::reorder_dictionary_for_sharing();
1297
1298 tty->print("Removing java_mirror ... ");
1299 if (!MetaspaceShared::is_heap_object_archiving_allowed()) {
1300 clear_basic_type_mirrors();
1301 }
1302 remove_java_mirror_in_classes();
1303 tty->print_cr("done. ");
1304 NOT_PRODUCT(SystemDictionary::verify();)
1305
1306 size_t buckets_bytes = SystemDictionary::count_bytes_for_buckets();
1307 char* buckets_top = _ro_region.allocate(buckets_bytes, sizeof(intptr_t));
1308 SystemDictionary::copy_buckets(buckets_top, _ro_region.top());
1309
1310 size_t table_bytes = SystemDictionary::count_bytes_for_table();
1311 char* table_top = _ro_region.allocate(table_bytes, sizeof(intptr_t));
1312 SystemDictionary::copy_table(table_top, _ro_region.top());
1313
1314 // Write the other data to the output array.
1315 WriteClosure wc(&_ro_region);
1316 MetaspaceShared::serialize(&wc);
1317
1318 char* newtop = _ro_region.top();
1319 ArchiveCompactor::alloc_stats()->record_other_type(int(newtop - oldtop), true);
1320 return buckets_top;
1321 }
1322
1323 void VM_PopulateDumpSharedSpace::doit() {
1324 Thread* THREAD = VMThread::vm_thread();
1325
1326 NOT_PRODUCT(SystemDictionary::verify();)
1327 // The following guarantee is meant to ensure that no loader constraints
1328 // exist yet, since the constraints table is not shared. This becomes
1329 // more important now that we don't re-initialize vtables/itables for
1330 // shared classes at runtime, where constraints were previously created.
1331 guarantee(SystemDictionary::constraints()->number_of_entries() == 0,
1332 "loader constraints are not saved");
1333 guarantee(SystemDictionary::placeholders()->number_of_entries() == 0,
1334 "placeholders are not saved");
1335 // Revisit and implement this if we prelink method handle call sites:
1336 guarantee(SystemDictionary::invoke_method_table() == NULL ||
1337 SystemDictionary::invoke_method_table()->number_of_entries() == 0,
1338 "invoke method table is not saved");
1339
1340 // At this point, many classes have been loaded.
1341 // Gather systemDictionary classes in a global array and do everything to
1342 // that so we don't have to walk the SystemDictionary again.
1343 _global_klass_objects = new GrowableArray<Klass*>(1000);
1344 CollectClassesClosure collect_classes;
1345 ClassLoaderDataGraph::loaded_classes_do(&collect_classes);
1346
1347 tty->print_cr("Number of classes %d", _global_klass_objects->length());
1348 {
1349 int num_type_array = 0, num_obj_array = 0, num_inst = 0;
1350 for (int i = 0; i < _global_klass_objects->length(); i++) {
1351 Klass* k = _global_klass_objects->at(i);
1352 if (k->is_instance_klass()) {
1353 num_inst ++;
1354 } else if (k->is_objArray_klass()) {
1355 num_obj_array ++;
1356 } else {
1357 assert(k->is_typeArray_klass(), "sanity");
1358 num_type_array ++;
1359 }
1360 }
1361 tty->print_cr(" instance classes = %5d", num_inst);
1362 tty->print_cr(" obj array classes = %5d", num_obj_array);
1363 tty->print_cr(" type array classes = %5d", num_type_array);
1364 }
1365
1366 // Ensure the ConstMethods won't be modified at run-time
1367 tty->print("Updating ConstMethods ... ");
1368 rewrite_nofast_bytecodes_and_calculate_fingerprints();
1369 tty->print_cr("done. ");
1370
1371 // Move classes from platform/system dictionaries into the boot dictionary
1372 SystemDictionary::combine_shared_dictionaries();
1373
1374 // Remove all references outside the metadata
1375 tty->print("Removing unshareable information ... ");
1376 remove_unshareable_in_classes();
1377 tty->print_cr("done. ");
1378
1379 // We don't support archiving anonymous classes. Verify that they are not stored in
1380 // the any dictionaries.
1381 NOT_PRODUCT(assert_no_anonymoys_classes_in_dictionaries());
1382
1383 SystemDictionaryShared::finalize_verification_constraints();
1384
1385 ArchiveCompactor::initialize();
1386 ArchiveCompactor::copy_and_compact();
1387
1388 dump_symbols();
1389
1390 // Dump supported java heap objects
1391 _closed_archive_heap_regions = NULL;
1392 _open_archive_heap_regions = NULL;
1393 dump_java_heap_objects();
1394
1395 ArchiveCompactor::relocate_well_known_klasses();
1396
1397 char* read_only_tables_start = dump_read_only_tables();
1398 _ro_region.pack(&_md_region);
1399
1400 char* vtbl_list = _md_region.top();
1401 MetaspaceShared::allocate_cpp_vtable_clones();
1402 _md_region.pack(&_od_region);
1403
1404 // Relocate the archived class file data into the od region
1405 relocate_cached_class_file();
1406 _od_region.pack();
1407
1408 // The 5 core spaces are allocated consecutively mc->rw->ro->md->od, so there total size
1409 // is just the spaces between the two ends.
1410 size_t core_spaces_size = _od_region.end() - _mc_region.base();
1411 assert(core_spaces_size == (size_t)align_up(core_spaces_size, Metaspace::reserve_alignment()),
1412 "should already be aligned");
1413
1414 // During patching, some virtual methods may be called, so at this point
1415 // the vtables must contain valid methods (as filled in by CppVtableCloner::allocate).
1416 MetaspaceShared::patch_cpp_vtable_pointers();
1417
1418 // The vtable clones contain addresses of the current process.
1419 // We don't want to write these addresses into the archive.
1420 MetaspaceShared::zero_cpp_vtable_clones_for_writing();
1421
1422 // Create and write the archive file that maps the shared spaces.
1423
1424 FileMapInfo* mapinfo = new FileMapInfo();
1425 mapinfo->populate_header(os::vm_allocation_granularity());
1426 mapinfo->set_read_only_tables_start(read_only_tables_start);
1427 mapinfo->set_misc_data_patching_start(vtbl_list);
1428 mapinfo->set_cds_i2i_entry_code_buffers(MetaspaceShared::cds_i2i_entry_code_buffers());
1429 mapinfo->set_cds_i2i_entry_code_buffers_size(MetaspaceShared::cds_i2i_entry_code_buffers_size());
1430 mapinfo->set_core_spaces_size(core_spaces_size);
1431
1432 for (int pass=1; pass<=2; pass++) {
1433 if (pass == 1) {
1434 // The first pass doesn't actually write the data to disk. All it
1435 // does is to update the fields in the mapinfo->_header.
1436 } else {
1437 // After the first pass, the contents of mapinfo->_header are finalized,
1438 // so we can compute the header's CRC, and write the contents of the header
1439 // and the regions into disk.
1440 mapinfo->open_for_write();
1441 mapinfo->set_header_crc(mapinfo->compute_header_crc());
1442 }
1443 mapinfo->write_header();
1444
1445 // NOTE: md contains the trampoline code for method entries, which are patched at run time,
1446 // so it needs to be read/write.
1447 write_region(mapinfo, MetaspaceShared::mc, &_mc_region, /*read_only=*/false,/*allow_exec=*/true);
1448 write_region(mapinfo, MetaspaceShared::rw, &_rw_region, /*read_only=*/false,/*allow_exec=*/false);
1449 write_region(mapinfo, MetaspaceShared::ro, &_ro_region, /*read_only=*/true, /*allow_exec=*/false);
1450 write_region(mapinfo, MetaspaceShared::md, &_md_region, /*read_only=*/false,/*allow_exec=*/false);
1451 write_region(mapinfo, MetaspaceShared::od, &_od_region, /*read_only=*/true, /*allow_exec=*/false);
1452
1453 _total_string_region_size = mapinfo->write_archive_heap_regions(
1454 _closed_archive_heap_regions,
1455 MetaspaceShared::first_string,
1456 MetaspaceShared::max_strings);
1457 _total_open_archive_region_size = mapinfo->write_archive_heap_regions(
1458 _open_archive_heap_regions,
1459 MetaspaceShared::first_open_archive_heap_region,
1460 MetaspaceShared::max_open_archive_heap_region);
1461 }
1462
1463 mapinfo->close();
1464
1465 // Restore the vtable in case we invoke any virtual methods.
1466 MetaspaceShared::clone_cpp_vtables((intptr_t*)vtbl_list);
1467
1468 print_region_stats();
1469
1470 if (log_is_enabled(Info, cds)) {
1471 ArchiveCompactor::alloc_stats()->print_stats(int(_ro_region.used()), int(_rw_region.used()),
1472 int(_mc_region.used()), int(_md_region.used()));
1473 }
1474
1475 if (PrintSystemDictionaryAtExit) {
1476 SystemDictionary::print();
1477 }
1478 // There may be other pending VM operations that operate on the InstanceKlasses,
1479 // which will fail because InstanceKlasses::remove_unshareable_info()
1480 // has been called. Forget these operations and exit the VM directly.
1481 vm_direct_exit(0);
1482 }
1483
1484 void VM_PopulateDumpSharedSpace::print_region_stats() {
1485 // Print statistics of all the regions
1486 const size_t total_reserved = _ro_region.reserved() + _rw_region.reserved() +
1487 _mc_region.reserved() + _md_region.reserved() +
1488 _od_region.reserved() +
1489 _total_string_region_size +
1490 _total_open_archive_region_size;
1491 const size_t total_bytes = _ro_region.used() + _rw_region.used() +
1492 _mc_region.used() + _md_region.used() +
1493 _od_region.used() +
1494 _total_string_region_size +
1495 _total_open_archive_region_size;
1496 const double total_u_perc = percent_of(total_bytes, total_reserved);
1497
1498 _mc_region.print(total_reserved);
1499 _rw_region.print(total_reserved);
1500 _ro_region.print(total_reserved);
1501 _md_region.print(total_reserved);
1502 _od_region.print(total_reserved);
1503 print_heap_region_stats(_closed_archive_heap_regions, "st", total_reserved);
1504 print_heap_region_stats(_open_archive_heap_regions, "oa", total_reserved);
1505
1506 tty->print_cr("total : " SIZE_FORMAT_W(9) " [100.0%% of total] out of " SIZE_FORMAT_W(9) " bytes [%5.1f%% used]",
1507 total_bytes, total_reserved, total_u_perc);
1508 }
1509
1510 void VM_PopulateDumpSharedSpace::print_heap_region_stats(GrowableArray<MemRegion> *heap_mem,
1511 const char *name, const size_t total_size) {
1512 int arr_len = heap_mem == NULL ? 0 : heap_mem->length();
1513 for (int i = 0; i < arr_len; i++) {
1514 char* start = (char*)heap_mem->at(i).start();
1515 size_t size = heap_mem->at(i).byte_size();
1516 char* top = start + size;
1517 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,
1518 name, i, size, size/double(total_size)*100.0, size, p2i(start));
1519
1520 }
1521 }
1522
1523 // Update a Java object to point its Klass* to the new location after
1524 // shared archive has been compacted.
1525 void MetaspaceShared::relocate_klass_ptr(oop o) {
1526 assert(DumpSharedSpaces, "sanity");
1527 Klass* k = ArchiveCompactor::get_relocated_klass(o->klass());
1528 o->set_klass(k);
1529 }
1530
1531 Klass* MetaspaceShared::get_relocated_klass(Klass *k) {
1532 assert(DumpSharedSpaces, "sanity");
1533 return ArchiveCompactor::get_relocated_klass(k);
1534 }
1535
1536 class LinkSharedClassesClosure : public KlassClosure {
1537 Thread* THREAD;
1538 bool _made_progress;
1539 public:
1540 LinkSharedClassesClosure(Thread* thread) : THREAD(thread), _made_progress(false) {}
1541
1542 void reset() { _made_progress = false; }
1543 bool made_progress() const { return _made_progress; }
1544
1545 void do_klass(Klass* k) {
1546 if (k->is_instance_klass()) {
1547 InstanceKlass* ik = InstanceKlass::cast(k);
1548 // Link the class to cause the bytecodes to be rewritten and the
1549 // cpcache to be created. Class verification is done according
1550 // to -Xverify setting.
1551 _made_progress |= MetaspaceShared::try_link_class(ik, THREAD);
1552 guarantee(!HAS_PENDING_EXCEPTION, "exception in link_class");
1553
1554 ik->constants()->resolve_class_constants(THREAD);
1555 }
1556 }
1557 };
1558
1559 class CheckSharedClassesClosure : public KlassClosure {
1560 bool _made_progress;
1561 public:
1562 CheckSharedClassesClosure() : _made_progress(false) {}
1563
1564 void reset() { _made_progress = false; }
1565 bool made_progress() const { return _made_progress; }
1566 void do_klass(Klass* k) {
1567 if (k->is_instance_klass() && InstanceKlass::cast(k)->check_sharing_error_state()) {
1568 _made_progress = true;
1569 }
1570 }
1571 };
1572
1573 void MetaspaceShared::check_shared_class_loader_type(Klass* k) {
1574 if (k->is_instance_klass()) {
1575 InstanceKlass* ik = InstanceKlass::cast(k);
1576 u2 loader_type = ik->loader_type();
1577 ResourceMark rm;
1578 guarantee(loader_type != 0,
1579 "Class loader type is not set for this class %s", ik->name()->as_C_string());
1580 }
1581 }
1582
1583 void MetaspaceShared::link_and_cleanup_shared_classes(TRAPS) {
1584 // We need to iterate because verification may cause additional classes
1585 // to be loaded.
1586 LinkSharedClassesClosure link_closure(THREAD);
1587 do {
1588 link_closure.reset();
1589 ClassLoaderDataGraph::loaded_classes_do(&link_closure);
1590 guarantee(!HAS_PENDING_EXCEPTION, "exception in link_class");
1591 } while (link_closure.made_progress());
1592
1593 if (_has_error_classes) {
1594 // Mark all classes whose super class or interfaces failed verification.
1595 CheckSharedClassesClosure check_closure;
1596 do {
1597 // Not completely sure if we need to do this iteratively. Anyway,
1598 // we should come here only if there are unverifiable classes, which
1599 // shouldn't happen in normal cases. So better safe than sorry.
1600 check_closure.reset();
1601 ClassLoaderDataGraph::loaded_classes_do(&check_closure);
1602 } while (check_closure.made_progress());
1603
1604 if (IgnoreUnverifiableClassesDuringDump) {
1605 // This is useful when running JCK or SQE tests. You should not
1606 // enable this when running real apps.
1607 SystemDictionary::remove_classes_in_error_state();
1608 } else {
1609 tty->print_cr("Please remove the unverifiable classes from your class list and try again");
1610 exit(1);
1611 }
1612 }
1613 }
1614
1615 void MetaspaceShared::prepare_for_dumping() {
1616 Arguments::check_unsupported_dumping_properties();
1617 ClassLoader::initialize_shared_path();
1618 FileMapInfo::allocate_classpath_entry_table();
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->is_shared_boot_class())) {
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 during dumping, we need to temporarily
1735 // 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 MetaspaceShared::ArchivedObjectCache* MetaspaceShared::_archive_object_cache = NULL;
1825 oop MetaspaceShared::find_archived_heap_object(oop obj) {
1826 assert(DumpSharedSpaces, "dump-time only");
1827 ArchivedObjectCache* cache = MetaspaceShared::archive_object_cache();
1828 oop* p = cache->get(obj);
1829 if (p != NULL) {
1830 return *p;
1831 } else {
1832 return NULL;
1833 }
1834 }
1835
1836 oop MetaspaceShared::archive_heap_object(oop obj, Thread* THREAD) {
1837 assert(DumpSharedSpaces, "dump-time only");
1838
1839 oop ao = find_archived_heap_object(obj);
1840 if (ao != NULL) {
1841 // already archived
1842 return ao;
1843 }
1844
1845 int len = obj->size();
1846 if (G1CollectedHeap::heap()->is_archive_alloc_too_large(len)) {
1847 return NULL;
1848 }
1849
1850 int hash = obj->identity_hash();
1851 oop archived_oop = (oop)G1CollectedHeap::heap()->archive_mem_allocate(len);
1852 if (archived_oop != NULL) {
1853 Copy::aligned_disjoint_words((HeapWord*)obj, (HeapWord*)archived_oop, len);
1854 relocate_klass_ptr(archived_oop);
1855 ArchivedObjectCache* cache = MetaspaceShared::archive_object_cache();
1856 cache->put(obj, archived_oop);
1857 }
1858 log_debug(cds)("Archived heap object " PTR_FORMAT " ==> " PTR_FORMAT,
1859 p2i(obj), p2i(archived_oop));
1860 return archived_oop;
1861 }
1862
1863 void MetaspaceShared::archive_klass_objects(Thread* THREAD) {
1864 int i;
1865 for (i = 0; i < _global_klass_objects->length(); i++) {
1866 Klass* k = _global_klass_objects->at(i);
1867
1868 // archive mirror object
1869 java_lang_Class::archive_mirror(k, CHECK);
1870
1871 // archive the resolved_referenes array
1872 if (k->is_instance_klass()) {
1873 InstanceKlass* ik = InstanceKlass::cast(k);
1874 ik->constants()->archive_resolved_references(THREAD);
1875 }
1876 }
1877 }
1878
1879 void MetaspaceShared::fixup_mapped_heap_regions() {
1880 FileMapInfo *mapinfo = FileMapInfo::current_info();
1881 mapinfo->fixup_mapped_heap_regions();
1882 }
1883 #endif // INCLUDE_CDS_JAVA_HEAP
1884
1885 // Closure for serializing initialization data in from a data area
1886 // (ptr_array) read from the shared file.
1887
1888 class ReadClosure : public SerializeClosure {
1889 private:
1890 intptr_t** _ptr_array;
1891
1892 inline intptr_t nextPtr() {
1893 return *(*_ptr_array)++;
1894 }
1895
1896 public:
1897 ReadClosure(intptr_t** ptr_array) { _ptr_array = ptr_array; }
1898
1899 void do_ptr(void** p) {
1900 assert(*p == NULL, "initializing previous initialized pointer.");
1901 intptr_t obj = nextPtr();
1902 assert((intptr_t)obj >= 0 || (intptr_t)obj < -100,
1903 "hit tag while initializing ptrs.");
1904 *p = (void*)obj;
1905 }
1906
1907 void do_u4(u4* p) {
1908 intptr_t obj = nextPtr();
1909 *p = (u4)(uintx(obj));
1910 }
1911
1912 void do_tag(int tag) {
1913 int old_tag;
1914 old_tag = (int)(intptr_t)nextPtr();
1915 // do_int(&old_tag);
1916 assert(tag == old_tag, "old tag doesn't match");
1917 FileMapInfo::assert_mark(tag == old_tag);
1918 }
1919
1920 void do_oop(oop *p) {
1921 narrowOop o = (narrowOop)nextPtr();
1922 if (o == 0 || !MetaspaceShared::open_archive_heap_region_mapped()) {
1923 p = NULL;
1924 } else {
1925 assert(MetaspaceShared::is_heap_object_archiving_allowed(),
1926 "Archived heap object is not allowed");
1927 assert(MetaspaceShared::open_archive_heap_region_mapped(),
1928 "Open archive heap region is not mapped");
1929 RootAccess<IN_ARCHIVE_ROOT>::oop_store(p, oopDesc::decode_heap_oop_not_null(o));
1930 }
1931 }
1932
1933 void do_region(u_char* start, size_t size) {
1934 assert((intptr_t)start % sizeof(intptr_t) == 0, "bad alignment");
1935 assert(size % sizeof(intptr_t) == 0, "bad size");
1936 do_tag((int)size);
1937 while (size > 0) {
1938 *(intptr_t*)start = nextPtr();
1939 start += sizeof(intptr_t);
1940 size -= sizeof(intptr_t);
1941 }
1942 }
1943
1944 bool reading() const { return true; }
1945 };
1946
1947 // Return true if given address is in the misc data region
1948 bool MetaspaceShared::is_in_shared_region(const void* p, int idx) {
1949 return UseSharedSpaces && FileMapInfo::current_info()->is_in_shared_region(p, idx);
1950 }
1951
1952 bool MetaspaceShared::is_in_trampoline_frame(address addr) {
1953 if (UseSharedSpaces && is_in_shared_region(addr, MetaspaceShared::mc)) {
1954 return true;
1955 }
1956 return false;
1957 }
1958
1959 void MetaspaceShared::print_shared_spaces() {
1960 if (UseSharedSpaces) {
1961 FileMapInfo::current_info()->print_shared_spaces();
1962 }
1963 }
1964
1965
1966 // Map shared spaces at requested addresses and return if succeeded.
1967 bool MetaspaceShared::map_shared_spaces(FileMapInfo* mapinfo) {
1968 size_t image_alignment = mapinfo->alignment();
1969
1970 #ifndef _WINDOWS
1971 // Map in the shared memory and then map the regions on top of it.
1972 // On Windows, don't map the memory here because it will cause the
1973 // mappings of the regions to fail.
1974 ReservedSpace shared_rs = mapinfo->reserve_shared_memory();
1975 if (!shared_rs.is_reserved()) return false;
1976 #endif
1977
1978 assert(!DumpSharedSpaces, "Should not be called with DumpSharedSpaces");
1979
1980 char* ro_base = NULL; char* ro_top;
1981 char* rw_base = NULL; char* rw_top;
1982 char* mc_base = NULL; char* mc_top;
1983 char* md_base = NULL; char* md_top;
1984 char* od_base = NULL; char* od_top;
1985
1986 // Map each shared region
1987 if ((mc_base = mapinfo->map_region(mc, &mc_top)) != NULL &&
1988 (rw_base = mapinfo->map_region(rw, &rw_top)) != NULL &&
1989 (ro_base = mapinfo->map_region(ro, &ro_top)) != NULL &&
1990 (md_base = mapinfo->map_region(md, &md_top)) != NULL &&
1991 (od_base = mapinfo->map_region(od, &od_top)) != NULL &&
1992 (image_alignment == (size_t)os::vm_allocation_granularity()) &&
1993 mapinfo->validate_classpath_entry_table()) {
1994 // Success -- set up MetaspaceObj::_shared_metaspace_{base,top} for
1995 // fast checking in MetaspaceShared::is_in_shared_metaspace() and
1996 // MetaspaceObj::is_shared().
1997 //
1998 // We require that mc->rw->ro->md->od to be laid out consecutively, with no
1999 // gaps between them. That way, we can ensure that the OS won't be able to
2000 // allocate any new memory spaces inside _shared_metaspace_{base,top}, which
2001 // would mess up the simple comparision in MetaspaceShared::is_in_shared_metaspace().
2002 assert(mc_base < ro_base && mc_base < rw_base && mc_base < md_base && mc_base < od_base, "must be");
2003 assert(od_top > ro_top && od_top > rw_top && od_top > md_top && od_top > mc_top , "must be");
2004 assert(mc_top == rw_base, "must be");
2005 assert(rw_top == ro_base, "must be");
2006 assert(ro_top == md_base, "must be");
2007 assert(md_top == od_base, "must be");
2008
2009 MetaspaceObj::_shared_metaspace_base = (void*)mc_base;
2010 MetaspaceObj::_shared_metaspace_top = (void*)od_top;
2011 return true;
2012 } else {
2013 // If there was a failure in mapping any of the spaces, unmap the ones
2014 // that succeeded
2015 if (ro_base != NULL) mapinfo->unmap_region(ro);
2016 if (rw_base != NULL) mapinfo->unmap_region(rw);
2017 if (mc_base != NULL) mapinfo->unmap_region(mc);
2018 if (md_base != NULL) mapinfo->unmap_region(md);
2019 if (od_base != NULL) mapinfo->unmap_region(od);
2020 #ifndef _WINDOWS
2021 // Release the entire mapped region
2022 shared_rs.release();
2023 #endif
2024 // If -Xshare:on is specified, print out the error message and exit VM,
2025 // otherwise, set UseSharedSpaces to false and continue.
2026 if (RequireSharedSpaces || PrintSharedArchiveAndExit) {
2027 vm_exit_during_initialization("Unable to use shared archive.", "Failed map_region for using -Xshare:on.");
2028 } else {
2029 FLAG_SET_DEFAULT(UseSharedSpaces, false);
2030 }
2031 return false;
2032 }
2033 }
2034
2035 // Read the miscellaneous data from the shared file, and
2036 // serialize it out to its various destinations.
2037
2038 void MetaspaceShared::initialize_shared_spaces() {
2039 FileMapInfo *mapinfo = FileMapInfo::current_info();
2040 _cds_i2i_entry_code_buffers = mapinfo->cds_i2i_entry_code_buffers();
2041 _cds_i2i_entry_code_buffers_size = mapinfo->cds_i2i_entry_code_buffers_size();
2042 _core_spaces_size = mapinfo->core_spaces_size();
2043 char* buffer = mapinfo->misc_data_patching_start();
2044 clone_cpp_vtables((intptr_t*)buffer);
2045
2046 // The rest of the data is now stored in the RW region
2047 buffer = mapinfo->read_only_tables_start();
2048 int sharedDictionaryLen = *(intptr_t*)buffer;
2049 buffer += sizeof(intptr_t);
2050 int number_of_entries = *(intptr_t*)buffer;
2051 buffer += sizeof(intptr_t);
2052 SystemDictionary::set_shared_dictionary((HashtableBucket<mtClass>*)buffer,
2053 sharedDictionaryLen,
2054 number_of_entries);
2055 buffer += sharedDictionaryLen;
2056
2057 // The following data are the linked list elements
2058 // (HashtableEntry objects) for the shared dictionary table.
2059
2060 int len = *(intptr_t*)buffer; // skip over shared dictionary entries
2061 buffer += sizeof(intptr_t);
2062 buffer += len;
2063
2064 // Verify various attributes of the archive, plus initialize the
2065 // shared string/symbol tables
2066 intptr_t* array = (intptr_t*)buffer;
2067 ReadClosure rc(&array);
2068 serialize(&rc);
2069
2070 // Initialize the run-time symbol table.
2071 SymbolTable::create_table();
2072
2073 // Close the mapinfo file
2074 mapinfo->close();
2075
2076 if (PrintSharedArchiveAndExit) {
2077 if (PrintSharedDictionary) {
2078 tty->print_cr("\nShared classes:\n");
2079 SystemDictionary::print_shared(tty);
2080 }
2081 if (_archive_loading_failed) {
2082 tty->print_cr("archive is invalid");
2083 vm_exit(1);
2084 } else {
2085 tty->print_cr("archive is valid");
2086 vm_exit(0);
2087 }
2088 }
2089 }
2090
2091 // JVM/TI RedefineClasses() support:
2092 bool MetaspaceShared::remap_shared_readonly_as_readwrite() {
2093 assert(SafepointSynchronize::is_at_safepoint(), "must be at safepoint");
2094
2095 if (UseSharedSpaces) {
2096 // remap the shared readonly space to shared readwrite, private
2097 FileMapInfo* mapinfo = FileMapInfo::current_info();
2098 if (!mapinfo->remap_shared_readonly_as_readwrite()) {
2099 return false;
2100 }
2101 _remapped_readwrite = true;
2102 }
2103 return true;
2104 }
2105
2106 void MetaspaceShared::report_out_of_space(const char* name, size_t needed_bytes) {
2107 // This is highly unlikely to happen on 64-bits because we have reserved a 4GB space.
2108 // On 32-bit we reserve only 256MB so you could run out of space with 100,000 classes
2109 // or so.
2110 _mc_region.print_out_of_space_msg(name, needed_bytes);
2111 _rw_region.print_out_of_space_msg(name, needed_bytes);
2112 _ro_region.print_out_of_space_msg(name, needed_bytes);
2113 _md_region.print_out_of_space_msg(name, needed_bytes);
2114 _od_region.print_out_of_space_msg(name, needed_bytes);
2115
2116 vm_exit_during_initialization(err_msg("Unable to allocate from '%s' region", name),
2117 "Please reduce the number of shared classes.");
2118 }