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