1 /*
2 * Copyright (c) 2012, 2018, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 #include "precompiled.hpp"
26 #include "jvm.h"
27 #include "classfile/classListParser.hpp"
28 #include "classfile/classLoaderExt.hpp"
29 #include "classfile/dictionary.hpp"
30 #include "classfile/loaderConstraints.hpp"
31 #include "classfile/placeholders.hpp"
32 #include "classfile/symbolTable.hpp"
33 #include "classfile/stringTable.hpp"
34 #include "classfile/systemDictionary.hpp"
35 #include "classfile/systemDictionaryShared.hpp"
36 #include "code/codeCache.hpp"
37 #include "interpreter/bytecodeStream.hpp"
38 #include "interpreter/bytecodes.hpp"
39 #include "logging/log.hpp"
40 #include "logging/logMessage.hpp"
41 #include "memory/filemap.hpp"
42 #include "memory/heapShared.inline.hpp"
43 #include "memory/metaspace.hpp"
44 #include "memory/metaspaceClosure.hpp"
45 #include "memory/metaspaceShared.hpp"
46 #include "memory/resourceArea.hpp"
47 #include "oops/compressedOops.inline.hpp"
48 #include "oops/instanceClassLoaderKlass.hpp"
49 #include "oops/instanceMirrorKlass.hpp"
50 #include "oops/instanceRefKlass.hpp"
51 #include "oops/objArrayKlass.hpp"
52 #include "oops/objArrayOop.hpp"
53 #include "oops/oop.inline.hpp"
54 #include "oops/typeArrayKlass.hpp"
55 #include "prims/jvmtiRedefineClasses.hpp"
56 #include "runtime/handles.inline.hpp"
57 #include "runtime/os.hpp"
58 #include "runtime/safepointVerifiers.hpp"
59 #include "runtime/signature.hpp"
60 #include "runtime/timerTrace.hpp"
61 #include "runtime/vmThread.hpp"
62 #include "runtime/vm_operations.hpp"
63 #include "utilities/align.hpp"
64 #include "utilities/bitMap.hpp"
65 #include "utilities/defaultStream.hpp"
66 #include "utilities/hashtable.inline.hpp"
67 #if INCLUDE_G1GC
68 #include "gc/g1/g1Allocator.inline.hpp"
69 #include "gc/g1/g1CollectedHeap.hpp"
70 #endif
71
72 ReservedSpace MetaspaceShared::_shared_rs;
73 VirtualSpace MetaspaceShared::_shared_vs;
74 MetaspaceSharedStats MetaspaceShared::_stats;
75 bool MetaspaceShared::_has_error_classes;
76 bool MetaspaceShared::_archive_loading_failed = false;
77 bool MetaspaceShared::_remapped_readwrite = false;
78 bool MetaspaceShared::_open_archive_heap_region_mapped = false;
79 address MetaspaceShared::_cds_i2i_entry_code_buffers = NULL;
80 size_t MetaspaceShared::_cds_i2i_entry_code_buffers_size = 0;
81 size_t MetaspaceShared::_core_spaces_size = 0;
82
83 // The CDS archive is divided into the following regions:
84 // mc - misc code (the method entry trampolines)
85 // rw - read-write metadata
86 // ro - read-only metadata and read-only tables
87 // md - misc data (the c++ vtables)
88 // od - optional data (original class files)
89 //
90 // s0 - shared strings(closed archive heap space) #0
91 // s1 - shared strings(closed archive heap space) #1 (may be empty)
92 // oa0 - open archive heap space #0
93 // oa1 - open archive heap space #1 (may be empty)
94 //
95 // The mc, rw, ro, md and od regions are linearly allocated, starting from
96 // SharedBaseAddress, in the order of mc->rw->ro->md->od. The size of these 5 regions
97 // are page-aligned, and there's no gap between any consecutive regions.
98 //
99 // These 5 regions are populated in the following steps:
100 // [1] All classes are loaded in MetaspaceShared::preload_classes(). All metadata are
101 // temporarily allocated outside of the shared regions. Only the method entry
102 // trampolines are written into the mc region.
103 // [2] ArchiveCompactor copies RW metadata into the rw region.
104 // [3] ArchiveCompactor copies RO metadata into the ro region.
105 // [4] SymbolTable, StringTable, SystemDictionary, and a few other read-only data
106 // are copied into the ro region as read-only tables.
107 // [5] C++ vtables are copied into the md region.
108 // [6] Original class files are copied into the od region.
109 //
110 // The s0/s1 and oa0/oa1 regions are populated inside MetaspaceShared::dump_java_heap_objects.
111 // Their layout is independent of the other 5 regions.
112
113 class DumpRegion {
114 private:
115 const char* _name;
116 char* _base;
117 char* _top;
118 char* _end;
119 bool _is_packed;
120
121 char* expand_top_to(char* newtop) {
122 assert(is_allocatable(), "must be initialized and not packed");
123 assert(newtop >= _top, "must not grow backwards");
124 if (newtop > _end) {
125 MetaspaceShared::report_out_of_space(_name, newtop - _top);
126 ShouldNotReachHere();
127 }
128 MetaspaceShared::commit_shared_space_to(newtop);
129 _top = newtop;
130 return _top;
131 }
132
133 public:
134 DumpRegion(const char* name) : _name(name), _base(NULL), _top(NULL), _end(NULL), _is_packed(false) {}
135
136 char* allocate(size_t num_bytes, size_t alignment=BytesPerWord) {
137 char* p = (char*)align_up(_top, alignment);
138 char* newtop = p + align_up(num_bytes, alignment);
139 expand_top_to(newtop);
140 memset(p, 0, newtop - p);
141 return p;
142 }
143
144 void append_intptr_t(intptr_t n) {
145 assert(is_aligned(_top, sizeof(intptr_t)), "bad alignment");
146 intptr_t *p = (intptr_t*)_top;
147 char* newtop = _top + sizeof(intptr_t);
148 expand_top_to(newtop);
149 *p = n;
150 }
151
152 char* base() const { return _base; }
153 char* top() const { return _top; }
154 char* end() const { return _end; }
155 size_t reserved() const { return _end - _base; }
156 size_t used() const { return _top - _base; }
157 bool is_packed() const { return _is_packed; }
158 bool is_allocatable() const {
159 return !is_packed() && _base != NULL;
160 }
161
162 void print(size_t total_bytes) const {
163 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,
164 _name, used(), percent_of(used(), total_bytes), reserved(), percent_of(used(), reserved()), p2i(_base));
165 }
166 void print_out_of_space_msg(const char* failing_region, size_t needed_bytes) {
167 tty->print("[%-8s] " PTR_FORMAT " - " PTR_FORMAT " capacity =%9d, allocated =%9d",
168 _name, p2i(_base), p2i(_top), int(_end - _base), int(_top - _base));
169 if (strcmp(_name, failing_region) == 0) {
170 tty->print_cr(" required = %d", int(needed_bytes));
171 } else {
172 tty->cr();
173 }
174 }
175
176 void init(const ReservedSpace* rs) {
177 _base = _top = rs->base();
178 _end = rs->end();
179 }
180 void init(char* b, char* t, char* e) {
181 _base = b;
182 _top = t;
183 _end = e;
184 }
185
186 void pack(DumpRegion* next = NULL) {
187 assert(!is_packed(), "sanity");
188 _end = (char*)align_up(_top, Metaspace::reserve_alignment());
189 _is_packed = true;
190 if (next != NULL) {
191 next->_base = next->_top = this->_end;
192 next->_end = MetaspaceShared::shared_rs()->end();
193 }
194 }
195 bool contains(char* p) {
196 return base() <= p && p < top();
197 }
198 };
199
200
201 DumpRegion _mc_region("mc"), _ro_region("ro"), _rw_region("rw"), _md_region("md"), _od_region("od");
202 size_t _total_string_region_size = 0, _total_open_archive_region_size = 0;
203
204 char* MetaspaceShared::misc_code_space_alloc(size_t num_bytes) {
205 return _mc_region.allocate(num_bytes);
206 }
207
208 char* MetaspaceShared::read_only_space_alloc(size_t num_bytes) {
209 return _ro_region.allocate(num_bytes);
210 }
211
212 char* MetaspaceShared::read_only_space_top() {
213 return _ro_region.top();
214 }
215
216 void MetaspaceShared::initialize_runtime_shared_and_meta_spaces() {
217 assert(UseSharedSpaces, "Must be called when UseSharedSpaces is enabled");
218
219 // If using shared space, open the file that contains the shared space
220 // and map in the memory before initializing the rest of metaspace (so
221 // the addresses don't conflict)
222 address cds_address = NULL;
223 FileMapInfo* mapinfo = new FileMapInfo();
224
225 // Open the shared archive file, read and validate the header. If
226 // initialization fails, shared spaces [UseSharedSpaces] are
227 // disabled and the file is closed.
228 // Map in spaces now also
229 if (mapinfo->initialize() && map_shared_spaces(mapinfo)) {
230 size_t cds_total = core_spaces_size();
231 cds_address = (address)mapinfo->region_addr(0);
232 #ifdef _LP64
233 if (Metaspace::using_class_space()) {
234 char* cds_end = (char*)(cds_address + cds_total);
235 cds_end = (char *)align_up(cds_end, Metaspace::reserve_alignment());
236 // If UseCompressedClassPointers is set then allocate the metaspace area
237 // above the heap and above the CDS area (if it exists).
238 Metaspace::allocate_metaspace_compressed_klass_ptrs(cds_end, cds_address);
239 // map_heap_regions() compares the current narrow oop and klass encodings
240 // with the archived ones, so it must be done after all encodings are determined.
241 mapinfo->map_heap_regions();
242 }
243 Universe::set_narrow_klass_range(CompressedClassSpaceSize);
244 #endif // _LP64
245 } else {
246 assert(!mapinfo->is_open() && !UseSharedSpaces,
247 "archive file not closed or shared spaces not disabled.");
248 }
249 }
250
251 void MetaspaceShared::initialize_dumptime_shared_and_meta_spaces() {
252 assert(DumpSharedSpaces, "should be called for dump time only");
253 const size_t reserve_alignment = Metaspace::reserve_alignment();
254 bool large_pages = false; // No large pages when dumping the CDS archive.
255 char* shared_base = (char*)align_up((char*)SharedBaseAddress, reserve_alignment);
256
257 #ifdef _LP64
258 // On 64-bit VM, the heap and class space layout will be the same as if
259 // you're running in -Xshare:on mode:
260 //
261 // +-- SharedBaseAddress (default = 0x800000000)
262 // v
263 // +-..---------+---------+ ... +----+----+----+----+----+---------------+
264 // | Heap | Archive | | MC | RW | RO | MD | OD | class space |
265 // +-..---------+---------+ ... +----+----+----+----+----+---------------+
266 // |<-- MaxHeapSize -->| |<-- UnscaledClassSpaceMax = 4GB ------->|
267 //
268 const uint64_t UnscaledClassSpaceMax = (uint64_t(max_juint) + 1);
269 const size_t cds_total = align_down(UnscaledClassSpaceMax, reserve_alignment);
270 #else
271 // We don't support archives larger than 256MB on 32-bit due to limited virtual address space.
272 size_t cds_total = align_down(256*M, reserve_alignment);
273 #endif
274
275 // First try to reserve the space at the specified SharedBaseAddress.
276 _shared_rs = ReservedSpace(cds_total, reserve_alignment, large_pages, shared_base);
277 if (_shared_rs.is_reserved()) {
278 assert(shared_base == 0 || _shared_rs.base() == shared_base, "should match");
279 } else {
280 // Get a mmap region anywhere if the SharedBaseAddress fails.
281 _shared_rs = ReservedSpace(cds_total, reserve_alignment, large_pages);
282 }
283 if (!_shared_rs.is_reserved()) {
284 vm_exit_during_initialization("Unable to reserve memory for shared space",
285 err_msg(SIZE_FORMAT " bytes.", cds_total));
286 }
287
288 #ifdef _LP64
289 // During dump time, we allocate 4GB (UnscaledClassSpaceMax) of space and split it up:
290 // + The upper 1 GB is used as the "temporary compressed class space" -- preload_classes()
291 // will store Klasses into this space.
292 // + The lower 3 GB is used for the archive -- when preload_classes() is done,
293 // ArchiveCompactor will copy the class metadata into this space, first the RW parts,
294 // then the RO parts.
295
296 assert(UseCompressedOops && UseCompressedClassPointers,
297 "UseCompressedOops and UseCompressedClassPointers must be set");
298
299 size_t max_archive_size = align_down(cds_total * 3 / 4, reserve_alignment);
300 ReservedSpace tmp_class_space = _shared_rs.last_part(max_archive_size);
301 CompressedClassSpaceSize = align_down(tmp_class_space.size(), reserve_alignment);
302 _shared_rs = _shared_rs.first_part(max_archive_size);
303
304 // Set up compress class pointers.
305 Universe::set_narrow_klass_base((address)_shared_rs.base());
306 // Set narrow_klass_shift to be LogKlassAlignmentInBytes. This is consistent
307 // with AOT.
308 Universe::set_narrow_klass_shift(LogKlassAlignmentInBytes);
309 // Set the range of klass addresses to 4GB.
310 Universe::set_narrow_klass_range(cds_total);
311
312 Metaspace::initialize_class_space(tmp_class_space);
313 log_info(cds)("narrow_klass_base = " PTR_FORMAT ", narrow_klass_shift = %d",
314 p2i(Universe::narrow_klass_base()), Universe::narrow_klass_shift());
315
316 log_info(cds)("Allocated temporary class space: " SIZE_FORMAT " bytes at " PTR_FORMAT,
317 CompressedClassSpaceSize, p2i(tmp_class_space.base()));
318 #endif
319
320 // Start with 0 committed bytes. The memory will be committed as needed by
321 // MetaspaceShared::commit_shared_space_to().
322 if (!_shared_vs.initialize(_shared_rs, 0)) {
323 vm_exit_during_initialization("Unable to allocate memory for shared space");
324 }
325
326 _mc_region.init(&_shared_rs);
327 tty->print_cr("Allocated shared space: " SIZE_FORMAT " bytes at " PTR_FORMAT,
328 _shared_rs.size(), p2i(_shared_rs.base()));
329 }
330
331 // Called by universe_post_init()
332 void MetaspaceShared::post_initialize(TRAPS) {
333 if (UseSharedSpaces) {
334 int size = FileMapInfo::get_number_of_shared_paths();
335 if (size > 0) {
336 SystemDictionaryShared::allocate_shared_data_arrays(size, THREAD);
337 FileMapHeader* header = FileMapInfo::current_info()->header();
338 ClassLoaderExt::init_paths_start_index(header->_app_class_paths_start_index);
339 ClassLoaderExt::init_app_module_paths_start_index(header->_app_module_paths_start_index);
340 }
341 }
342
343 if (DumpSharedSpaces) {
344 if (SharedArchiveConfigFile) {
345 read_extra_data(SharedArchiveConfigFile, THREAD);
346 }
347 }
348 }
349
350 void MetaspaceShared::read_extra_data(const char* filename, TRAPS) {
351 HashtableTextDump reader(filename);
352 reader.check_version("VERSION: 1.0");
353
354 while (reader.remain() > 0) {
355 int utf8_length;
356 int prefix_type = reader.scan_prefix(&utf8_length);
357 ResourceMark rm(THREAD);
358 char* utf8_buffer = NEW_RESOURCE_ARRAY(char, utf8_length);
359 reader.get_utf8(utf8_buffer, utf8_length);
360
361 if (prefix_type == HashtableTextDump::SymbolPrefix) {
362 SymbolTable::new_symbol(utf8_buffer, utf8_length, THREAD);
363 } else{
364 assert(prefix_type == HashtableTextDump::StringPrefix, "Sanity");
365 utf8_buffer[utf8_length] = '\0';
366 oop s = StringTable::intern(utf8_buffer, THREAD);
367 }
368 }
369 }
370
371 void MetaspaceShared::commit_shared_space_to(char* newtop) {
372 assert(DumpSharedSpaces, "dump-time only");
373 char* base = _shared_rs.base();
374 size_t need_committed_size = newtop - base;
375 size_t has_committed_size = _shared_vs.committed_size();
376 if (need_committed_size < has_committed_size) {
377 return;
378 }
379
380 size_t min_bytes = need_committed_size - has_committed_size;
381 size_t preferred_bytes = 1 * M;
382 size_t uncommitted = _shared_vs.reserved_size() - has_committed_size;
383
384 size_t commit = MAX2(min_bytes, preferred_bytes);
385 assert(commit <= uncommitted, "sanity");
386
387 bool result = _shared_vs.expand_by(commit, false);
388 if (!result) {
389 vm_exit_during_initialization(err_msg("Failed to expand shared space to " SIZE_FORMAT " bytes",
390 need_committed_size));
391 }
392
393 log_info(cds)("Expanding shared spaces by " SIZE_FORMAT_W(7) " bytes [total " SIZE_FORMAT_W(9) " bytes ending at %p]",
394 commit, _shared_vs.actual_committed_size(), _shared_vs.high());
395 }
396
397 // Read/write a data stream for restoring/preserving metadata pointers and
398 // miscellaneous data from/to the shared archive file.
399
400 void MetaspaceShared::serialize(SerializeClosure* soc) {
401 int tag = 0;
402 soc->do_tag(--tag);
403
404 // Verify the sizes of various metadata in the system.
405 soc->do_tag(sizeof(Method));
406 soc->do_tag(sizeof(ConstMethod));
407 soc->do_tag(arrayOopDesc::base_offset_in_bytes(T_BYTE));
408 soc->do_tag(sizeof(ConstantPool));
409 soc->do_tag(sizeof(ConstantPoolCache));
410 soc->do_tag(objArrayOopDesc::base_offset_in_bytes());
411 soc->do_tag(typeArrayOopDesc::base_offset_in_bytes(T_BYTE));
412 soc->do_tag(sizeof(Symbol));
413
414 // Dump/restore miscellaneous metadata.
415 Universe::serialize(soc);
416 soc->do_tag(--tag);
417
418 // Dump/restore references to commonly used names and signatures.
419 vmSymbols::serialize(soc);
420 soc->do_tag(--tag);
421
422 // Dump/restore the symbol and string tables
423 SymbolTable::serialize(soc);
424 StringTable::serialize(soc);
425 soc->do_tag(--tag);
426
427 JavaClasses::serialize_offsets(soc);
428 InstanceMirrorKlass::serialize_offsets(soc);
429 soc->do_tag(--tag);
430
431 soc->do_tag(666);
432 }
433
434 address MetaspaceShared::cds_i2i_entry_code_buffers(size_t total_size) {
435 if (DumpSharedSpaces) {
436 if (_cds_i2i_entry_code_buffers == NULL) {
437 _cds_i2i_entry_code_buffers = (address)misc_code_space_alloc(total_size);
438 _cds_i2i_entry_code_buffers_size = total_size;
439 }
440 } else if (UseSharedSpaces) {
441 assert(_cds_i2i_entry_code_buffers != NULL, "must already been initialized");
442 } else {
443 return NULL;
444 }
445
446 assert(_cds_i2i_entry_code_buffers_size == total_size, "must not change");
447 return _cds_i2i_entry_code_buffers;
448 }
449
450 // CDS code for dumping shared archive.
451
452 // Global object for holding classes that have been loaded. Since this
453 // is run at a safepoint just before exit, this is the entire set of classes.
454 static GrowableArray<Klass*>* _global_klass_objects;
455
456 static void collect_array_classes(Klass* k) {
457 _global_klass_objects->append_if_missing(k);
458 if (k->is_array_klass()) {
459 // Add in the array classes too
460 ArrayKlass* ak = ArrayKlass::cast(k);
461 Klass* h = ak->higher_dimension();
462 if (h != NULL) {
463 h->array_klasses_do(collect_array_classes);
464 }
465 }
466 }
467
468 class CollectClassesClosure : public KlassClosure {
469 void do_klass(Klass* k) {
470 if (!(k->is_instance_klass() && InstanceKlass::cast(k)->is_in_error_state())) {
471 if (k->is_instance_klass() && InstanceKlass::cast(k)->signers() != NULL) {
472 // Mark any class with signers and don't add to the _global_klass_objects
473 k->set_has_signer_and_not_archived();
474 } else {
475 _global_klass_objects->append_if_missing(k);
476 }
477 }
478 if (k->is_array_klass()) {
479 // Add in the array classes too
480 ArrayKlass* ak = ArrayKlass::cast(k);
481 Klass* h = ak->higher_dimension();
482 if (h != NULL) {
483 h->array_klasses_do(collect_array_classes);
484 }
485 }
486 }
487 };
488
489 static void remove_unshareable_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_unshareable_info();
497 }
498 }
499 }
500
501 static void remove_java_mirror_in_classes() {
502 for (int i = 0; i < _global_klass_objects->length(); i++) {
503 Klass* k = _global_klass_objects->at(i);
504 if (!k->is_objArray_klass()) {
505 // InstanceKlass and TypeArrayKlass will in turn call remove_unshareable_info
506 // on their array classes.
507 assert(k->is_instance_klass() || k->is_typeArray_klass(), "must be");
508 k->remove_java_mirror();
509 }
510 }
511 }
512
513 static void clear_basic_type_mirrors() {
514 assert(!MetaspaceShared::is_heap_object_archiving_allowed(), "Sanity");
515 Universe::set_int_mirror(NULL);
516 Universe::set_float_mirror(NULL);
517 Universe::set_double_mirror(NULL);
518 Universe::set_byte_mirror(NULL);
519 Universe::set_bool_mirror(NULL);
520 Universe::set_char_mirror(NULL);
521 Universe::set_long_mirror(NULL);
522 Universe::set_short_mirror(NULL);
523 Universe::set_void_mirror(NULL);
524 }
525
526 static void rewrite_nofast_bytecode(Method* method) {
527 BytecodeStream bcs(method);
528 while (!bcs.is_last_bytecode()) {
529 Bytecodes::Code opcode = bcs.next();
530 switch (opcode) {
531 case Bytecodes::_getfield: *bcs.bcp() = Bytecodes::_nofast_getfield; break;
532 case Bytecodes::_putfield: *bcs.bcp() = Bytecodes::_nofast_putfield; break;
533 case Bytecodes::_aload_0: *bcs.bcp() = Bytecodes::_nofast_aload_0; break;
534 case Bytecodes::_iload: {
535 if (!bcs.is_wide()) {
536 *bcs.bcp() = Bytecodes::_nofast_iload;
537 }
538 break;
539 }
540 default: break;
541 }
542 }
543 }
544
545 // Walk all methods in the class list to ensure that they won't be modified at
546 // run time. This includes:
547 // [1] Rewrite all bytecodes as needed, so that the ConstMethod* will not be modified
548 // at run time by RewriteBytecodes/RewriteFrequentPairs
549 // [2] Assign a fingerprint, so one doesn't need to be assigned at run-time.
550 static void rewrite_nofast_bytecodes_and_calculate_fingerprints() {
551 for (int i = 0; i < _global_klass_objects->length(); i++) {
552 Klass* k = _global_klass_objects->at(i);
553 if (k->is_instance_klass()) {
554 InstanceKlass* ik = InstanceKlass::cast(k);
555 for (int i = 0; i < ik->methods()->length(); i++) {
556 Method* m = ik->methods()->at(i);
557 rewrite_nofast_bytecode(m);
558 Fingerprinter fp(m);
559 // The side effect of this call sets method's fingerprint field.
560 fp.fingerprint();
561 }
562 }
563 }
564 }
565
566 static void relocate_cached_class_file() {
567 for (int i = 0; i < _global_klass_objects->length(); i++) {
568 Klass* k = _global_klass_objects->at(i);
569 if (k->is_instance_klass()) {
570 InstanceKlass* ik = InstanceKlass::cast(k);
571 JvmtiCachedClassFileData* p = ik->get_archived_class_data();
572 if (p != NULL) {
573 int size = offset_of(JvmtiCachedClassFileData, data) + p->length;
574 JvmtiCachedClassFileData* q = (JvmtiCachedClassFileData*)_od_region.allocate(size);
575 q->length = p->length;
576 memcpy(q->data, p->data, p->length);
577 ik->set_archived_class_data(q);
578 }
579 }
580 }
581 }
582
583 NOT_PRODUCT(
584 static void assert_not_unsafe_anonymous_class(InstanceKlass* k) {
585 assert(!(k->is_unsafe_anonymous()), "cannot archive unsafe anonymous classes");
586 }
587
588 // Unsafe anonymous classes are not stored inside any dictionaries.
589 static void assert_no_unsafe_anonymous_classes_in_dictionaries() {
590 ClassLoaderDataGraph::dictionary_classes_do(assert_not_unsafe_anonymous_class);
591 })
592
593 // Objects of the Metadata types (such as Klass and ConstantPool) have C++ vtables.
594 // (In GCC this is the field <Type>::_vptr, i.e., first word in the object.)
595 //
596 // Addresses of the vtables and the methods may be different across JVM runs,
597 // if libjvm.so is dynamically loaded at a different base address.
598 //
599 // To ensure that the Metadata objects in the CDS archive always have the correct vtable:
600 //
601 // + at dump time: we redirect the _vptr to point to our own vtables inside
602 // the CDS image
603 // + at run time: we clone the actual contents of the vtables from libjvm.so
604 // into our own tables.
605
606 // Currently, the archive contain ONLY the following types of objects that have C++ vtables.
607 #define CPP_VTABLE_PATCH_TYPES_DO(f) \
608 f(ConstantPool) \
609 f(InstanceKlass) \
610 f(InstanceClassLoaderKlass) \
611 f(InstanceMirrorKlass) \
612 f(InstanceRefKlass) \
613 f(Method) \
614 f(ObjArrayKlass) \
615 f(TypeArrayKlass)
616
617 class CppVtableInfo {
618 intptr_t _vtable_size;
619 intptr_t _cloned_vtable[1];
620 public:
621 static int num_slots(int vtable_size) {
622 return 1 + vtable_size; // Need to add the space occupied by _vtable_size;
623 }
624 int vtable_size() { return int(uintx(_vtable_size)); }
625 void set_vtable_size(int n) { _vtable_size = intptr_t(n); }
626 intptr_t* cloned_vtable() { return &_cloned_vtable[0]; }
627 void zero() { memset(_cloned_vtable, 0, sizeof(intptr_t) * vtable_size()); }
628 // Returns the address of the next CppVtableInfo that can be placed immediately after this CppVtableInfo
629 static size_t byte_size(int vtable_size) {
630 CppVtableInfo i;
631 return pointer_delta(&i._cloned_vtable[vtable_size], &i, sizeof(u1));
632 }
633 };
634
635 template <class T> class CppVtableCloner : public T {
636 static intptr_t* vtable_of(Metadata& m) {
637 return *((intptr_t**)&m);
638 }
639 static CppVtableInfo* _info;
640
641 static int get_vtable_length(const char* name);
642
643 public:
644 // Allocate and initialize the C++ vtable, starting from top, but do not go past end.
645 static intptr_t* allocate(const char* name);
646
647 // Clone the vtable to ...
648 static intptr_t* clone_vtable(const char* name, CppVtableInfo* info);
649
650 static void zero_vtable_clone() {
651 assert(DumpSharedSpaces, "dump-time only");
652 _info->zero();
653 }
654
655 // Switch the vtable pointer to point to the cloned vtable.
656 static void patch(Metadata* obj) {
657 assert(DumpSharedSpaces, "dump-time only");
658 *(void**)obj = (void*)(_info->cloned_vtable());
659 }
660
661 static bool is_valid_shared_object(const T* obj) {
662 intptr_t* vptr = *(intptr_t**)obj;
663 return vptr == _info->cloned_vtable();
664 }
665 };
666
667 template <class T> CppVtableInfo* CppVtableCloner<T>::_info = NULL;
668
669 template <class T>
670 intptr_t* CppVtableCloner<T>::allocate(const char* name) {
671 assert(is_aligned(_md_region.top(), sizeof(intptr_t)), "bad alignment");
672 int n = get_vtable_length(name);
673 _info = (CppVtableInfo*)_md_region.allocate(CppVtableInfo::byte_size(n), sizeof(intptr_t));
674 _info->set_vtable_size(n);
675
676 intptr_t* p = clone_vtable(name, _info);
677 assert((char*)p == _md_region.top(), "must be");
678
679 return p;
680 }
681
682 template <class T>
683 intptr_t* CppVtableCloner<T>::clone_vtable(const char* name, CppVtableInfo* info) {
684 if (!DumpSharedSpaces) {
685 assert(_info == 0, "_info is initialized only at dump time");
686 _info = info; // Remember it -- it will be used by MetaspaceShared::is_valid_shared_method()
687 }
688 T tmp; // Allocate temporary dummy metadata object to get to the original vtable.
689 int n = info->vtable_size();
690 intptr_t* srcvtable = vtable_of(tmp);
691 intptr_t* dstvtable = info->cloned_vtable();
692
693 // We already checked (and, if necessary, adjusted n) when the vtables were allocated, so we are
694 // safe to do memcpy.
695 log_debug(cds, vtables)("Copying %3d vtable entries for %s", n, name);
696 memcpy(dstvtable, srcvtable, sizeof(intptr_t) * n);
697 return dstvtable + n;
698 }
699
700 // To determine the size of the vtable for each type, we use the following
701 // trick by declaring 2 subclasses:
702 //
703 // class CppVtableTesterA: public InstanceKlass {virtual int last_virtual_method() {return 1;} };
704 // class CppVtableTesterB: public InstanceKlass {virtual void* last_virtual_method() {return NULL}; };
705 //
706 // CppVtableTesterA and CppVtableTesterB's vtables have the following properties:
707 // - Their size (N+1) is exactly one more than the size of InstanceKlass's vtable (N)
708 // - The first N entries have are exactly the same as in InstanceKlass's vtable.
709 // - Their last entry is different.
710 //
711 // So to determine the value of N, we just walk CppVtableTesterA and CppVtableTesterB's tables
712 // and find the first entry that's different.
713 //
714 // This works on all C++ compilers supported by Oracle, but you may need to tweak it for more
715 // esoteric compilers.
716
717 template <class T> class CppVtableTesterB: public T {
718 public:
719 virtual int last_virtual_method() {return 1;}
720 };
721
722 template <class T> class CppVtableTesterA : public T {
723 public:
724 virtual void* last_virtual_method() {
725 // Make this different than CppVtableTesterB::last_virtual_method so the C++
726 // compiler/linker won't alias the two functions.
727 return NULL;
728 }
729 };
730
731 template <class T>
732 int CppVtableCloner<T>::get_vtable_length(const char* name) {
733 CppVtableTesterA<T> a;
734 CppVtableTesterB<T> b;
735
736 intptr_t* avtable = vtable_of(a);
737 intptr_t* bvtable = vtable_of(b);
738
739 // Start at slot 1, because slot 0 may be RTTI (on Solaris/Sparc)
740 int vtable_len = 1;
741 for (; ; vtable_len++) {
742 if (avtable[vtable_len] != bvtable[vtable_len]) {
743 break;
744 }
745 }
746 log_debug(cds, vtables)("Found %3d vtable entries for %s", vtable_len, name);
747
748 return vtable_len;
749 }
750
751 #define ALLOC_CPP_VTABLE_CLONE(c) \
752 CppVtableCloner<c>::allocate(#c);
753
754 #define CLONE_CPP_VTABLE(c) \
755 p = CppVtableCloner<c>::clone_vtable(#c, (CppVtableInfo*)p);
756
757 #define ZERO_CPP_VTABLE(c) \
758 CppVtableCloner<c>::zero_vtable_clone();
759
760 // This can be called at both dump time and run time.
761 intptr_t* MetaspaceShared::clone_cpp_vtables(intptr_t* p) {
762 assert(DumpSharedSpaces || UseSharedSpaces, "sanity");
763 CPP_VTABLE_PATCH_TYPES_DO(CLONE_CPP_VTABLE);
764 return p;
765 }
766
767 void MetaspaceShared::zero_cpp_vtable_clones_for_writing() {
768 assert(DumpSharedSpaces, "dump-time only");
769 CPP_VTABLE_PATCH_TYPES_DO(ZERO_CPP_VTABLE);
770 }
771
772 // Allocate and initialize the C++ vtables, starting from top, but do not go past end.
773 void MetaspaceShared::allocate_cpp_vtable_clones() {
774 assert(DumpSharedSpaces, "dump-time only");
775 // Layout (each slot is a intptr_t):
776 // [number of slots in the first vtable = n1]
777 // [ <n1> slots for the first vtable]
778 // [number of slots in the first second = n2]
779 // [ <n2> slots for the second vtable]
780 // ...
781 // The order of the vtables is the same as the CPP_VTAB_PATCH_TYPES_DO macro.
782 CPP_VTABLE_PATCH_TYPES_DO(ALLOC_CPP_VTABLE_CLONE);
783 }
784
785 // Switch the vtable pointer to point to the cloned vtable. We assume the
786 // vtable pointer is in first slot in object.
787 void MetaspaceShared::patch_cpp_vtable_pointers() {
788 int n = _global_klass_objects->length();
789 for (int i = 0; i < n; i++) {
790 Klass* obj = _global_klass_objects->at(i);
791 if (obj->is_instance_klass()) {
792 InstanceKlass* ik = InstanceKlass::cast(obj);
793 if (ik->is_class_loader_instance_klass()) {
794 CppVtableCloner<InstanceClassLoaderKlass>::patch(ik);
795 } else if (ik->is_reference_instance_klass()) {
796 CppVtableCloner<InstanceRefKlass>::patch(ik);
797 } else if (ik->is_mirror_instance_klass()) {
798 CppVtableCloner<InstanceMirrorKlass>::patch(ik);
799 } else {
800 CppVtableCloner<InstanceKlass>::patch(ik);
801 }
802 ConstantPool* cp = ik->constants();
803 CppVtableCloner<ConstantPool>::patch(cp);
804 for (int j = 0; j < ik->methods()->length(); j++) {
805 Method* m = ik->methods()->at(j);
806 CppVtableCloner<Method>::patch(m);
807 assert(CppVtableCloner<Method>::is_valid_shared_object(m), "must be");
808 }
809 } else if (obj->is_objArray_klass()) {
810 CppVtableCloner<ObjArrayKlass>::patch(obj);
811 } else {
812 assert(obj->is_typeArray_klass(), "sanity");
813 CppVtableCloner<TypeArrayKlass>::patch(obj);
814 }
815 }
816 }
817
818 bool MetaspaceShared::is_valid_shared_method(const Method* m) {
819 assert(is_in_shared_metaspace(m), "must be");
820 return CppVtableCloner<Method>::is_valid_shared_object(m);
821 }
822
823 // Closure for serializing initialization data out to a data area to be
824 // written to the shared file.
825
826 class WriteClosure : public SerializeClosure {
827 private:
828 DumpRegion* _dump_region;
829
830 public:
831 WriteClosure(DumpRegion* r) {
832 _dump_region = r;
833 }
834
835 void do_ptr(void** p) {
836 _dump_region->append_intptr_t((intptr_t)*p);
837 }
838
839 void do_u4(u4* p) {
840 void* ptr = (void*)(uintx(*p));
841 do_ptr(&ptr);
842 }
843
844 void do_tag(int tag) {
845 _dump_region->append_intptr_t((intptr_t)tag);
846 }
847
848 void do_oop(oop* o) {
849 if (*o == NULL) {
850 _dump_region->append_intptr_t(0);
851 } else {
852 assert(MetaspaceShared::is_heap_object_archiving_allowed(),
853 "Archiving heap object is not allowed");
854 _dump_region->append_intptr_t(
855 (intptr_t)CompressedOops::encode_not_null(*o));
856 }
857 }
858
859 void do_region(u_char* start, size_t size) {
860 assert((intptr_t)start % sizeof(intptr_t) == 0, "bad alignment");
861 assert(size % sizeof(intptr_t) == 0, "bad size");
862 do_tag((int)size);
863 while (size > 0) {
864 _dump_region->append_intptr_t(*(intptr_t*)start);
865 start += sizeof(intptr_t);
866 size -= sizeof(intptr_t);
867 }
868 }
869
870 bool reading() const { return false; }
871 };
872
873 // This is for dumping detailed statistics for the allocations
874 // in the shared spaces.
875 class DumpAllocStats : public ResourceObj {
876 public:
877
878 // Here's poor man's enum inheritance
879 #define SHAREDSPACE_OBJ_TYPES_DO(f) \
880 METASPACE_OBJ_TYPES_DO(f) \
881 f(SymbolHashentry) \
882 f(SymbolBucket) \
883 f(StringHashentry) \
884 f(StringBucket) \
885 f(Other)
886
887 enum Type {
888 // Types are MetaspaceObj::ClassType, MetaspaceObj::SymbolType, etc
889 SHAREDSPACE_OBJ_TYPES_DO(METASPACE_OBJ_TYPE_DECLARE)
890 _number_of_types
891 };
892
893 static const char * type_name(Type type) {
894 switch(type) {
895 SHAREDSPACE_OBJ_TYPES_DO(METASPACE_OBJ_TYPE_NAME_CASE)
896 default:
897 ShouldNotReachHere();
898 return NULL;
899 }
900 }
901
902 public:
903 enum { RO = 0, RW = 1 };
904
905 int _counts[2][_number_of_types];
906 int _bytes [2][_number_of_types];
907
908 DumpAllocStats() {
909 memset(_counts, 0, sizeof(_counts));
910 memset(_bytes, 0, sizeof(_bytes));
911 };
912
913 void record(MetaspaceObj::Type type, int byte_size, bool read_only) {
914 assert(int(type) >= 0 && type < MetaspaceObj::_number_of_types, "sanity");
915 int which = (read_only) ? RO : RW;
916 _counts[which][type] ++;
917 _bytes [which][type] += byte_size;
918 }
919
920 void record_other_type(int byte_size, bool read_only) {
921 int which = (read_only) ? RO : RW;
922 _bytes [which][OtherType] += byte_size;
923 }
924 void print_stats(int ro_all, int rw_all, int mc_all, int md_all);
925 };
926
927 void DumpAllocStats::print_stats(int ro_all, int rw_all, int mc_all, int md_all) {
928 // Calculate size of data that was not allocated by Metaspace::allocate()
929 MetaspaceSharedStats *stats = MetaspaceShared::stats();
930
931 // symbols
932 _counts[RO][SymbolHashentryType] = stats->symbol.hashentry_count;
933 _bytes [RO][SymbolHashentryType] = stats->symbol.hashentry_bytes;
934
935 _counts[RO][SymbolBucketType] = stats->symbol.bucket_count;
936 _bytes [RO][SymbolBucketType] = stats->symbol.bucket_bytes;
937
938 // strings
939 _counts[RO][StringHashentryType] = stats->string.hashentry_count;
940 _bytes [RO][StringHashentryType] = stats->string.hashentry_bytes;
941
942 _counts[RO][StringBucketType] = stats->string.bucket_count;
943 _bytes [RO][StringBucketType] = stats->string.bucket_bytes;
944
945 // TODO: count things like dictionary, vtable, etc
946 _bytes[RW][OtherType] += mc_all + md_all;
947 rw_all += mc_all + md_all; // mc/md are mapped Read/Write
948
949 // prevent divide-by-zero
950 if (ro_all < 1) {
951 ro_all = 1;
952 }
953 if (rw_all < 1) {
954 rw_all = 1;
955 }
956
957 int all_ro_count = 0;
958 int all_ro_bytes = 0;
959 int all_rw_count = 0;
960 int all_rw_bytes = 0;
961
962 // To make fmt_stats be a syntactic constant (for format warnings), use #define.
963 #define fmt_stats "%-20s: %8d %10d %5.1f | %8d %10d %5.1f | %8d %10d %5.1f"
964 const char *sep = "--------------------+---------------------------+---------------------------+--------------------------";
965 const char *hdr = " ro_cnt ro_bytes % | rw_cnt rw_bytes % | all_cnt all_bytes %";
966
967 LogMessage(cds) msg;
968
969 msg.info("Detailed metadata info (excluding od/st regions; rw stats include md/mc regions):");
970 msg.info("%s", hdr);
971 msg.info("%s", sep);
972 for (int type = 0; type < int(_number_of_types); type ++) {
973 const char *name = type_name((Type)type);
974 int ro_count = _counts[RO][type];
975 int ro_bytes = _bytes [RO][type];
976 int rw_count = _counts[RW][type];
977 int rw_bytes = _bytes [RW][type];
978 int count = ro_count + rw_count;
979 int bytes = ro_bytes + rw_bytes;
980
981 double ro_perc = percent_of(ro_bytes, ro_all);
982 double rw_perc = percent_of(rw_bytes, rw_all);
983 double perc = percent_of(bytes, ro_all + rw_all);
984
985 msg.info(fmt_stats, name,
986 ro_count, ro_bytes, ro_perc,
987 rw_count, rw_bytes, rw_perc,
988 count, bytes, perc);
989
990 all_ro_count += ro_count;
991 all_ro_bytes += ro_bytes;
992 all_rw_count += rw_count;
993 all_rw_bytes += rw_bytes;
994 }
995
996 int all_count = all_ro_count + all_rw_count;
997 int all_bytes = all_ro_bytes + all_rw_bytes;
998
999 double all_ro_perc = percent_of(all_ro_bytes, ro_all);
1000 double all_rw_perc = percent_of(all_rw_bytes, rw_all);
1001 double all_perc = percent_of(all_bytes, ro_all + rw_all);
1002
1003 msg.info("%s", sep);
1004 msg.info(fmt_stats, "Total",
1005 all_ro_count, all_ro_bytes, all_ro_perc,
1006 all_rw_count, all_rw_bytes, all_rw_perc,
1007 all_count, all_bytes, all_perc);
1008
1009 assert(all_ro_bytes == ro_all, "everything should have been counted");
1010 assert(all_rw_bytes == rw_all, "everything should have been counted");
1011
1012 #undef fmt_stats
1013 }
1014
1015 // Populate the shared space.
1016
1017 class VM_PopulateDumpSharedSpace: public VM_Operation {
1018 private:
1019 GrowableArray<MemRegion> *_closed_archive_heap_regions;
1020 GrowableArray<MemRegion> *_open_archive_heap_regions;
1021
1022 GrowableArray<ArchiveHeapOopmapInfo> *_closed_archive_heap_oopmaps;
1023 GrowableArray<ArchiveHeapOopmapInfo> *_open_archive_heap_oopmaps;
1024
1025 void dump_java_heap_objects() NOT_CDS_JAVA_HEAP_RETURN;
1026 void dump_archive_heap_oopmaps() NOT_CDS_JAVA_HEAP_RETURN;
1027 void dump_archive_heap_oopmaps(GrowableArray<MemRegion>* regions,
1028 GrowableArray<ArchiveHeapOopmapInfo>* oopmaps);
1029 void dump_symbols();
1030 char* dump_read_only_tables();
1031 void print_region_stats();
1032 void print_heap_region_stats(GrowableArray<MemRegion> *heap_mem,
1033 const char *name, const size_t total_size);
1034 public:
1035
1036 VMOp_Type type() const { return VMOp_PopulateDumpSharedSpace; }
1037 void doit(); // outline because gdb sucks
1038 static void write_region(FileMapInfo* mapinfo, int region, DumpRegion* space, bool read_only, bool allow_exec);
1039 bool allow_nested_vm_operations() const { return true; }
1040 }; // class VM_PopulateDumpSharedSpace
1041
1042 class SortedSymbolClosure: public SymbolClosure {
1043 GrowableArray<Symbol*> _symbols;
1044 virtual void do_symbol(Symbol** sym) {
1045 assert((*sym)->is_permanent(), "archived symbols must be permanent");
1046 _symbols.append(*sym);
1047 }
1048 static int compare_symbols_by_address(Symbol** a, Symbol** b) {
1049 if (a[0] < b[0]) {
1050 return -1;
1051 } else if (a[0] == b[0]) {
1052 return 0;
1053 } else {
1054 return 1;
1055 }
1056 }
1057
1058 public:
1059 SortedSymbolClosure() {
1060 SymbolTable::symbols_do(this);
1061 _symbols.sort(compare_symbols_by_address);
1062 }
1063 GrowableArray<Symbol*>* get_sorted_symbols() {
1064 return &_symbols;
1065 }
1066 };
1067
1068 // ArchiveCompactor --
1069 //
1070 // This class is the central piece of shared archive compaction -- all metaspace data are
1071 // initially allocated outside of the shared regions. ArchiveCompactor copies the
1072 // metaspace data into their final location in the shared regions.
1073
1074 class ArchiveCompactor : AllStatic {
1075 static DumpAllocStats* _alloc_stats;
1076 static SortedSymbolClosure* _ssc;
1077
1078 static unsigned my_hash(const address& a) {
1079 return primitive_hash<address>(a);
1080 }
1081 static bool my_equals(const address& a0, const address& a1) {
1082 return primitive_equals<address>(a0, a1);
1083 }
1084 typedef ResourceHashtable<
1085 address, address,
1086 ArchiveCompactor::my_hash, // solaris compiler doesn't like: primitive_hash<address>
1087 ArchiveCompactor::my_equals, // solaris compiler doesn't like: primitive_equals<address>
1088 16384, ResourceObj::C_HEAP> RelocationTable;
1089 static RelocationTable* _new_loc_table;
1090
1091 public:
1092 static void initialize() {
1093 _alloc_stats = new(ResourceObj::C_HEAP, mtInternal)DumpAllocStats;
1094 _new_loc_table = new(ResourceObj::C_HEAP, mtInternal)RelocationTable;
1095 }
1096 static DumpAllocStats* alloc_stats() {
1097 return _alloc_stats;
1098 }
1099
1100 static void allocate(MetaspaceClosure::Ref* ref, bool read_only) {
1101 address obj = ref->obj();
1102 int bytes = ref->size() * BytesPerWord;
1103 char* p;
1104 size_t alignment = BytesPerWord;
1105 char* oldtop;
1106 char* newtop;
1107
1108 if (read_only) {
1109 oldtop = _ro_region.top();
1110 p = _ro_region.allocate(bytes, alignment);
1111 newtop = _ro_region.top();
1112 } else {
1113 oldtop = _rw_region.top();
1114 p = _rw_region.allocate(bytes, alignment);
1115 newtop = _rw_region.top();
1116 }
1117 memcpy(p, obj, bytes);
1118 bool isnew = _new_loc_table->put(obj, (address)p);
1119 log_trace(cds)("Copy: " PTR_FORMAT " ==> " PTR_FORMAT " %d", p2i(obj), p2i(p), bytes);
1120 assert(isnew, "must be");
1121
1122 _alloc_stats->record(ref->msotype(), int(newtop - oldtop), read_only);
1123 if (ref->msotype() == MetaspaceObj::SymbolType) {
1124 uintx delta = MetaspaceShared::object_delta(p);
1125 if (delta > MAX_SHARED_DELTA) {
1126 // This is just a sanity check and should not appear in any real world usage. This
1127 // happens only if you allocate more than 2GB of Symbols and would require
1128 // millions of shared classes.
1129 vm_exit_during_initialization("Too many Symbols in the CDS archive",
1130 "Please reduce the number of shared classes.");
1131 }
1132 }
1133 }
1134
1135 static address get_new_loc(MetaspaceClosure::Ref* ref) {
1136 address* pp = _new_loc_table->get(ref->obj());
1137 assert(pp != NULL, "must be");
1138 return *pp;
1139 }
1140
1141 private:
1142 // Makes a shallow copy of visited MetaspaceObj's
1143 class ShallowCopier: public UniqueMetaspaceClosure {
1144 bool _read_only;
1145 public:
1146 ShallowCopier(bool read_only) : _read_only(read_only) {}
1147
1148 virtual void do_unique_ref(Ref* ref, bool read_only) {
1149 if (read_only == _read_only) {
1150 allocate(ref, read_only);
1151 }
1152 }
1153 };
1154
1155 // Relocate embedded pointers within a MetaspaceObj's shallow copy
1156 class ShallowCopyEmbeddedRefRelocator: public UniqueMetaspaceClosure {
1157 public:
1158 virtual void do_unique_ref(Ref* ref, bool read_only) {
1159 address new_loc = get_new_loc(ref);
1160 RefRelocator refer;
1161 ref->metaspace_pointers_do_at(&refer, new_loc);
1162 }
1163 };
1164
1165 // Relocate a reference to point to its shallow copy
1166 class RefRelocator: public MetaspaceClosure {
1167 public:
1168 virtual bool do_ref(Ref* ref, bool read_only) {
1169 if (ref->not_null()) {
1170 ref->update(get_new_loc(ref));
1171 }
1172 return false; // Do not recurse.
1173 }
1174 };
1175
1176 #ifdef ASSERT
1177 class IsRefInArchiveChecker: public MetaspaceClosure {
1178 public:
1179 virtual bool do_ref(Ref* ref, bool read_only) {
1180 if (ref->not_null()) {
1181 char* obj = (char*)ref->obj();
1182 assert(_ro_region.contains(obj) || _rw_region.contains(obj),
1183 "must be relocated to point to CDS archive");
1184 }
1185 return false; // Do not recurse.
1186 }
1187 };
1188 #endif
1189
1190 public:
1191 static void copy_and_compact() {
1192 // We should no longer allocate anything from the metaspace, so that
1193 // we can have a stable set of MetaspaceObjs to work with.
1194 Metaspace::freeze();
1195
1196 ResourceMark rm;
1197 SortedSymbolClosure the_ssc; // StackObj
1198 _ssc = &the_ssc;
1199
1200 tty->print_cr("Scanning all metaspace objects ... ");
1201 {
1202 // allocate and shallow-copy RW objects, immediately following the MC region
1203 tty->print_cr("Allocating RW objects ... ");
1204 _mc_region.pack(&_rw_region);
1205
1206 ResourceMark rm;
1207 ShallowCopier rw_copier(false);
1208 iterate_roots(&rw_copier);
1209 }
1210 {
1211 // allocate and shallow-copy of RO object, immediately following the RW region
1212 tty->print_cr("Allocating RO objects ... ");
1213 _rw_region.pack(&_ro_region);
1214
1215 ResourceMark rm;
1216 ShallowCopier ro_copier(true);
1217 iterate_roots(&ro_copier);
1218 }
1219 {
1220 tty->print_cr("Relocating embedded pointers ... ");
1221 ResourceMark rm;
1222 ShallowCopyEmbeddedRefRelocator emb_reloc;
1223 iterate_roots(&emb_reloc);
1224 }
1225 {
1226 tty->print_cr("Relocating external roots ... ");
1227 ResourceMark rm;
1228 RefRelocator ext_reloc;
1229 iterate_roots(&ext_reloc);
1230 }
1231
1232 #ifdef ASSERT
1233 {
1234 tty->print_cr("Verifying external roots ... ");
1235 ResourceMark rm;
1236 IsRefInArchiveChecker checker;
1237 iterate_roots(&checker);
1238 }
1239 #endif
1240
1241
1242 // cleanup
1243 _ssc = NULL;
1244 }
1245
1246 // We must relocate the System::_well_known_klasses only after we have copied the
1247 // java objects in during dump_java_heap_objects(): during the object copy, we operate on
1248 // old objects which assert that their klass is the original klass.
1249 static void relocate_well_known_klasses() {
1250 {
1251 tty->print_cr("Relocating SystemDictionary::_well_known_klasses[] ... ");
1252 ResourceMark rm;
1253 RefRelocator ext_reloc;
1254 SystemDictionary::well_known_klasses_do(&ext_reloc);
1255 }
1256 // NOTE: after this point, we shouldn't have any globals that can reach the old
1257 // objects.
1258
1259 // We cannot use any of the objects in the heap anymore (except for the objects
1260 // in the CDS shared string regions) because their headers no longer point to
1261 // valid Klasses.
1262 }
1263
1264 static void iterate_roots(MetaspaceClosure* it) {
1265 GrowableArray<Symbol*>* symbols = _ssc->get_sorted_symbols();
1266 for (int i=0; i<symbols->length(); i++) {
1267 it->push(symbols->adr_at(i));
1268 }
1269 if (_global_klass_objects != NULL) {
1270 // Need to fix up the pointers
1271 for (int i = 0; i < _global_klass_objects->length(); i++) {
1272 // NOTE -- this requires that the vtable is NOT yet patched, or else we are hosed.
1273 it->push(_global_klass_objects->adr_at(i));
1274 }
1275 }
1276 FileMapInfo::metaspace_pointers_do(it);
1277 SystemDictionary::classes_do(it);
1278 Universe::metaspace_pointers_do(it);
1279 SymbolTable::metaspace_pointers_do(it);
1280 vmSymbols::metaspace_pointers_do(it);
1281 }
1282
1283 static Klass* get_relocated_klass(Klass* orig_klass) {
1284 assert(DumpSharedSpaces, "dump time only");
1285 address* pp = _new_loc_table->get((address)orig_klass);
1286 assert(pp != NULL, "must be");
1287 Klass* klass = (Klass*)(*pp);
1288 assert(klass->is_klass(), "must be");
1289 return klass;
1290 }
1291 };
1292
1293 DumpAllocStats* ArchiveCompactor::_alloc_stats;
1294 SortedSymbolClosure* ArchiveCompactor::_ssc;
1295 ArchiveCompactor::RelocationTable* ArchiveCompactor::_new_loc_table;
1296
1297 void VM_PopulateDumpSharedSpace::write_region(FileMapInfo* mapinfo, int region_idx,
1298 DumpRegion* dump_region, bool read_only, bool allow_exec) {
1299 mapinfo->write_region(region_idx, dump_region->base(), dump_region->used(), read_only, allow_exec);
1300 }
1301
1302 void VM_PopulateDumpSharedSpace::dump_symbols() {
1303 tty->print_cr("Dumping symbol table ...");
1304
1305 NOT_PRODUCT(SymbolTable::verify());
1306 SymbolTable::write_to_archive();
1307 }
1308
1309 char* VM_PopulateDumpSharedSpace::dump_read_only_tables() {
1310 char* oldtop = _ro_region.top();
1311 // Reorder the system dictionary. Moving the symbols affects
1312 // how the hash table indices are calculated.
1313 SystemDictionary::reorder_dictionary_for_sharing();
1314
1315 tty->print("Removing java_mirror ... ");
1316 if (!MetaspaceShared::is_heap_object_archiving_allowed()) {
1317 clear_basic_type_mirrors();
1318 }
1319 remove_java_mirror_in_classes();
1320 tty->print_cr("done. ");
1321 NOT_PRODUCT(SystemDictionary::verify();)
1322
1323 size_t buckets_bytes = SystemDictionary::count_bytes_for_buckets();
1324 char* buckets_top = _ro_region.allocate(buckets_bytes, sizeof(intptr_t));
1325 SystemDictionary::copy_buckets(buckets_top, _ro_region.top());
1326
1327 size_t table_bytes = SystemDictionary::count_bytes_for_table();
1328 char* table_top = _ro_region.allocate(table_bytes, sizeof(intptr_t));
1329 SystemDictionary::copy_table(table_top, _ro_region.top());
1330
1331 // Write the archived object sub-graph infos. For each klass with sub-graphs,
1332 // the info includes the static fields (sub-graph entry points) and Klasses
1333 // of objects included in the sub-graph.
1334 HeapShared::write_archived_subgraph_infos();
1335
1336 // Write the other data to the output array.
1337 WriteClosure wc(&_ro_region);
1338 MetaspaceShared::serialize(&wc);
1339
1340 // Write the bitmaps for patching the archive heap regions
1341 dump_archive_heap_oopmaps();
1342
1343 char* newtop = _ro_region.top();
1344 ArchiveCompactor::alloc_stats()->record_other_type(int(newtop - oldtop), true);
1345 return buckets_top;
1346 }
1347
1348 void VM_PopulateDumpSharedSpace::doit() {
1349 Thread* THREAD = VMThread::vm_thread();
1350
1351 FileMapInfo::check_nonempty_dir_in_shared_path_table();
1352
1353 NOT_PRODUCT(SystemDictionary::verify();)
1354 // The following guarantee is meant to ensure that no loader constraints
1355 // exist yet, since the constraints table is not shared. This becomes
1356 // more important now that we don't re-initialize vtables/itables for
1357 // shared classes at runtime, where constraints were previously created.
1358 guarantee(SystemDictionary::constraints()->number_of_entries() == 0,
1359 "loader constraints are not saved");
1360 guarantee(SystemDictionary::placeholders()->number_of_entries() == 0,
1361 "placeholders are not saved");
1362 // Revisit and implement this if we prelink method handle call sites:
1363 guarantee(SystemDictionary::invoke_method_table() == NULL ||
1364 SystemDictionary::invoke_method_table()->number_of_entries() == 0,
1365 "invoke method table is not saved");
1366
1367 // At this point, many classes have been loaded.
1368 // Gather systemDictionary classes in a global array and do everything to
1369 // that so we don't have to walk the SystemDictionary again.
1370 _global_klass_objects = new GrowableArray<Klass*>(1000);
1371 CollectClassesClosure collect_classes;
1372 ClassLoaderDataGraph::loaded_classes_do(&collect_classes);
1373
1374 tty->print_cr("Number of classes %d", _global_klass_objects->length());
1375 {
1376 int num_type_array = 0, num_obj_array = 0, num_inst = 0;
1377 for (int i = 0; i < _global_klass_objects->length(); i++) {
1378 Klass* k = _global_klass_objects->at(i);
1379 if (k->is_instance_klass()) {
1380 num_inst ++;
1381 } else if (k->is_objArray_klass()) {
1382 num_obj_array ++;
1383 } else {
1384 assert(k->is_typeArray_klass(), "sanity");
1385 num_type_array ++;
1386 }
1387 }
1388 tty->print_cr(" instance classes = %5d", num_inst);
1389 tty->print_cr(" obj array classes = %5d", num_obj_array);
1390 tty->print_cr(" type array classes = %5d", num_type_array);
1391 }
1392
1393 // Ensure the ConstMethods won't be modified at run-time
1394 tty->print("Updating ConstMethods ... ");
1395 rewrite_nofast_bytecodes_and_calculate_fingerprints();
1396 tty->print_cr("done. ");
1397
1398 // Move classes from platform/system dictionaries into the boot dictionary
1399 SystemDictionary::combine_shared_dictionaries();
1400
1401 // Make sure all classes have a correct loader type.
1402 ClassLoaderData::the_null_class_loader_data()->dictionary()->classes_do(MetaspaceShared::check_shared_class_loader_type);
1403
1404 // Remove all references outside the metadata
1405 tty->print("Removing unshareable information ... ");
1406 remove_unshareable_in_classes();
1407 tty->print_cr("done. ");
1408
1409 // We don't support archiving unsafe anonymous classes. Verify that they are not stored in
1410 // any dictionaries.
1411 NOT_PRODUCT(assert_no_unsafe_anonymous_classes_in_dictionaries());
1412
1413 SystemDictionaryShared::finalize_verification_constraints();
1414
1415 ArchiveCompactor::initialize();
1416 ArchiveCompactor::copy_and_compact();
1417
1418 dump_symbols();
1419
1420 // Dump supported java heap objects
1421 _closed_archive_heap_regions = NULL;
1422 _open_archive_heap_regions = NULL;
1423 dump_java_heap_objects();
1424
1425 ArchiveCompactor::relocate_well_known_klasses();
1426
1427 char* read_only_tables_start = dump_read_only_tables();
1428 _ro_region.pack(&_md_region);
1429
1430 char* vtbl_list = _md_region.top();
1431 MetaspaceShared::allocate_cpp_vtable_clones();
1432 _md_region.pack(&_od_region);
1433
1434 // Relocate the archived class file data into the od region
1435 relocate_cached_class_file();
1436 _od_region.pack();
1437
1438 // The 5 core spaces are allocated consecutively mc->rw->ro->md->od, so there total size
1439 // is just the spaces between the two ends.
1440 size_t core_spaces_size = _od_region.end() - _mc_region.base();
1441 assert(core_spaces_size == (size_t)align_up(core_spaces_size, Metaspace::reserve_alignment()),
1442 "should already be aligned");
1443
1444 // During patching, some virtual methods may be called, so at this point
1445 // the vtables must contain valid methods (as filled in by CppVtableCloner::allocate).
1446 MetaspaceShared::patch_cpp_vtable_pointers();
1447
1448 // The vtable clones contain addresses of the current process.
1449 // We don't want to write these addresses into the archive.
1450 MetaspaceShared::zero_cpp_vtable_clones_for_writing();
1451
1452 // Create and write the archive file that maps the shared spaces.
1453
1454 FileMapInfo* mapinfo = new FileMapInfo();
1455 mapinfo->populate_header(os::vm_allocation_granularity());
1456 mapinfo->set_read_only_tables_start(read_only_tables_start);
1457 mapinfo->set_misc_data_patching_start(vtbl_list);
1458 mapinfo->set_cds_i2i_entry_code_buffers(MetaspaceShared::cds_i2i_entry_code_buffers());
1459 mapinfo->set_cds_i2i_entry_code_buffers_size(MetaspaceShared::cds_i2i_entry_code_buffers_size());
1460 mapinfo->set_core_spaces_size(core_spaces_size);
1461
1462 for (int pass=1; pass<=2; pass++) {
1463 if (pass == 1) {
1464 // The first pass doesn't actually write the data to disk. All it
1465 // does is to update the fields in the mapinfo->_header.
1466 } else {
1467 // After the first pass, the contents of mapinfo->_header are finalized,
1468 // so we can compute the header's CRC, and write the contents of the header
1469 // and the regions into disk.
1470 mapinfo->open_for_write();
1471 mapinfo->set_header_crc(mapinfo->compute_header_crc());
1472 }
1473 mapinfo->write_header();
1474
1475 // NOTE: md contains the trampoline code for method entries, which are patched at run time,
1476 // so it needs to be read/write.
1477 write_region(mapinfo, MetaspaceShared::mc, &_mc_region, /*read_only=*/false,/*allow_exec=*/true);
1478 write_region(mapinfo, MetaspaceShared::rw, &_rw_region, /*read_only=*/false,/*allow_exec=*/false);
1479 write_region(mapinfo, MetaspaceShared::ro, &_ro_region, /*read_only=*/true, /*allow_exec=*/false);
1480 write_region(mapinfo, MetaspaceShared::md, &_md_region, /*read_only=*/false,/*allow_exec=*/false);
1481 write_region(mapinfo, MetaspaceShared::od, &_od_region, /*read_only=*/true, /*allow_exec=*/false);
1482
1483 _total_string_region_size = mapinfo->write_archive_heap_regions(
1484 _closed_archive_heap_regions,
1485 _closed_archive_heap_oopmaps,
1486 MetaspaceShared::first_string,
1487 MetaspaceShared::max_strings);
1488 _total_open_archive_region_size = mapinfo->write_archive_heap_regions(
1489 _open_archive_heap_regions,
1490 _open_archive_heap_oopmaps,
1491 MetaspaceShared::first_open_archive_heap_region,
1492 MetaspaceShared::max_open_archive_heap_region);
1493 }
1494
1495 mapinfo->close();
1496
1497 // Restore the vtable in case we invoke any virtual methods.
1498 MetaspaceShared::clone_cpp_vtables((intptr_t*)vtbl_list);
1499
1500 print_region_stats();
1501
1502 if (log_is_enabled(Info, cds)) {
1503 ArchiveCompactor::alloc_stats()->print_stats(int(_ro_region.used()), int(_rw_region.used()),
1504 int(_mc_region.used()), int(_md_region.used()));
1505 }
1506
1507 if (PrintSystemDictionaryAtExit) {
1508 SystemDictionary::print();
1509 }
1510 // There may be other pending VM operations that operate on the InstanceKlasses,
1511 // which will fail because InstanceKlasses::remove_unshareable_info()
1512 // has been called. Forget these operations and exit the VM directly.
1513 vm_direct_exit(0);
1514 }
1515
1516 void VM_PopulateDumpSharedSpace::print_region_stats() {
1517 // Print statistics of all the regions
1518 const size_t total_reserved = _ro_region.reserved() + _rw_region.reserved() +
1519 _mc_region.reserved() + _md_region.reserved() +
1520 _od_region.reserved() +
1521 _total_string_region_size +
1522 _total_open_archive_region_size;
1523 const size_t total_bytes = _ro_region.used() + _rw_region.used() +
1524 _mc_region.used() + _md_region.used() +
1525 _od_region.used() +
1526 _total_string_region_size +
1527 _total_open_archive_region_size;
1528 const double total_u_perc = percent_of(total_bytes, total_reserved);
1529
1530 _mc_region.print(total_reserved);
1531 _rw_region.print(total_reserved);
1532 _ro_region.print(total_reserved);
1533 _md_region.print(total_reserved);
1534 _od_region.print(total_reserved);
1535 print_heap_region_stats(_closed_archive_heap_regions, "st", total_reserved);
1536 print_heap_region_stats(_open_archive_heap_regions, "oa", total_reserved);
1537
1538 tty->print_cr("total : " SIZE_FORMAT_W(9) " [100.0%% of total] out of " SIZE_FORMAT_W(9) " bytes [%5.1f%% used]",
1539 total_bytes, total_reserved, total_u_perc);
1540 }
1541
1542 void VM_PopulateDumpSharedSpace::print_heap_region_stats(GrowableArray<MemRegion> *heap_mem,
1543 const char *name, const size_t total_size) {
1544 int arr_len = heap_mem == NULL ? 0 : heap_mem->length();
1545 for (int i = 0; i < arr_len; i++) {
1546 char* start = (char*)heap_mem->at(i).start();
1547 size_t size = heap_mem->at(i).byte_size();
1548 char* top = start + size;
1549 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,
1550 name, i, size, size/double(total_size)*100.0, size, p2i(start));
1551
1552 }
1553 }
1554
1555 // Update a Java object to point its Klass* to the new location after
1556 // shared archive has been compacted.
1557 void MetaspaceShared::relocate_klass_ptr(oop o) {
1558 assert(DumpSharedSpaces, "sanity");
1559 Klass* k = ArchiveCompactor::get_relocated_klass(o->klass());
1560 o->set_klass(k);
1561 }
1562
1563 Klass* MetaspaceShared::get_relocated_klass(Klass *k) {
1564 assert(DumpSharedSpaces, "sanity");
1565 return ArchiveCompactor::get_relocated_klass(k);
1566 }
1567
1568 class LinkSharedClassesClosure : public KlassClosure {
1569 Thread* THREAD;
1570 bool _made_progress;
1571 public:
1572 LinkSharedClassesClosure(Thread* thread) : THREAD(thread), _made_progress(false) {}
1573
1574 void reset() { _made_progress = false; }
1575 bool made_progress() const { return _made_progress; }
1576
1577 void do_klass(Klass* k) {
1578 if (k->is_instance_klass()) {
1579 InstanceKlass* ik = InstanceKlass::cast(k);
1580 // Link the class to cause the bytecodes to be rewritten and the
1581 // cpcache to be created. Class verification is done according
1582 // to -Xverify setting.
1583 _made_progress |= MetaspaceShared::try_link_class(ik, THREAD);
1584 guarantee(!HAS_PENDING_EXCEPTION, "exception in link_class");
1585
1586 ik->constants()->resolve_class_constants(THREAD);
1587 }
1588 }
1589 };
1590
1591 class CheckSharedClassesClosure : public KlassClosure {
1592 bool _made_progress;
1593 public:
1594 CheckSharedClassesClosure() : _made_progress(false) {}
1595
1596 void reset() { _made_progress = false; }
1597 bool made_progress() const { return _made_progress; }
1598 void do_klass(Klass* k) {
1599 if (k->is_instance_klass() && InstanceKlass::cast(k)->check_sharing_error_state()) {
1600 _made_progress = true;
1601 }
1602 }
1603 };
1604
1605 void MetaspaceShared::check_shared_class_loader_type(InstanceKlass* ik) {
1606 ResourceMark rm;
1607 if (ik->shared_classpath_index() == UNREGISTERED_INDEX) {
1608 guarantee(ik->loader_type() == 0,
1609 "Class loader type must not be set for this class %s", ik->name()->as_C_string());
1610 } else {
1611 guarantee(ik->loader_type() != 0,
1612 "Class loader type must be set for this class %s", ik->name()->as_C_string());
1613 }
1614 }
1615
1616 void MetaspaceShared::link_and_cleanup_shared_classes(TRAPS) {
1617 // We need to iterate because verification may cause additional classes
1618 // to be loaded.
1619 LinkSharedClassesClosure link_closure(THREAD);
1620 do {
1621 link_closure.reset();
1622 ClassLoaderDataGraph::unlocked_loaded_classes_do(&link_closure);
1623 guarantee(!HAS_PENDING_EXCEPTION, "exception in link_class");
1624 } while (link_closure.made_progress());
1625
1626 if (_has_error_classes) {
1627 // Mark all classes whose super class or interfaces failed verification.
1628 CheckSharedClassesClosure check_closure;
1629 do {
1630 // Not completely sure if we need to do this iteratively. Anyway,
1631 // we should come here only if there are unverifiable classes, which
1632 // shouldn't happen in normal cases. So better safe than sorry.
1633 check_closure.reset();
1634 ClassLoaderDataGraph::unlocked_loaded_classes_do(&check_closure);
1635 } while (check_closure.made_progress());
1636
1637 if (IgnoreUnverifiableClassesDuringDump) {
1638 // This is useful when running JCK or SQE tests. You should not
1639 // enable this when running real apps.
1640 SystemDictionary::remove_classes_in_error_state();
1641 } else {
1642 tty->print_cr("Please remove the unverifiable classes from your class list and try again");
1643 exit(1);
1644 }
1645 }
1646 }
1647
1648 void MetaspaceShared::prepare_for_dumping() {
1649 Arguments::check_unsupported_dumping_properties();
1650 ClassLoader::initialize_shared_path();
1651 }
1652
1653 // Preload classes from a list, populate the shared spaces and dump to a
1654 // file.
1655 void MetaspaceShared::preload_and_dump(TRAPS) {
1656 { TraceTime timer("Dump Shared Spaces", TRACETIME_LOG(Info, startuptime));
1657 ResourceMark rm;
1658 char class_list_path_str[JVM_MAXPATHLEN];
1659 // Preload classes to be shared.
1660 // Should use some os:: method rather than fopen() here. aB.
1661 const char* class_list_path;
1662 if (SharedClassListFile == NULL) {
1663 // Construct the path to the class list (in jre/lib)
1664 // Walk up two directories from the location of the VM and
1665 // optionally tack on "lib" (depending on platform)
1666 os::jvm_path(class_list_path_str, sizeof(class_list_path_str));
1667 for (int i = 0; i < 3; i++) {
1668 char *end = strrchr(class_list_path_str, *os::file_separator());
1669 if (end != NULL) *end = '\0';
1670 }
1671 int class_list_path_len = (int)strlen(class_list_path_str);
1672 if (class_list_path_len >= 3) {
1673 if (strcmp(class_list_path_str + class_list_path_len - 3, "lib") != 0) {
1674 if (class_list_path_len < JVM_MAXPATHLEN - 4) {
1675 jio_snprintf(class_list_path_str + class_list_path_len,
1676 sizeof(class_list_path_str) - class_list_path_len,
1677 "%slib", os::file_separator());
1678 class_list_path_len += 4;
1679 }
1680 }
1681 }
1682 if (class_list_path_len < JVM_MAXPATHLEN - 10) {
1683 jio_snprintf(class_list_path_str + class_list_path_len,
1684 sizeof(class_list_path_str) - class_list_path_len,
1685 "%sclasslist", os::file_separator());
1686 }
1687 class_list_path = class_list_path_str;
1688 } else {
1689 class_list_path = SharedClassListFile;
1690 }
1691
1692 tty->print_cr("Loading classes to share ...");
1693 _has_error_classes = false;
1694 int class_count = preload_classes(class_list_path, THREAD);
1695 if (ExtraSharedClassListFile) {
1696 class_count += preload_classes(ExtraSharedClassListFile, THREAD);
1697 }
1698 tty->print_cr("Loading classes to share: done.");
1699
1700 log_info(cds)("Shared spaces: preloaded %d classes", class_count);
1701
1702 // Rewrite and link classes
1703 tty->print_cr("Rewriting and linking classes ...");
1704
1705 // Link any classes which got missed. This would happen if we have loaded classes that
1706 // were not explicitly specified in the classlist. E.g., if an interface implemented by class K
1707 // fails verification, all other interfaces that were not specified in the classlist but
1708 // are implemented by K are not verified.
1709 link_and_cleanup_shared_classes(CATCH);
1710 tty->print_cr("Rewriting and linking classes: done");
1711
1712 SystemDictionary::clear_invoke_method_table();
1713 HeapShared::init_archivable_static_fields(THREAD);
1714
1715 VM_PopulateDumpSharedSpace op;
1716 VMThread::execute(&op);
1717 }
1718 }
1719
1720
1721 int MetaspaceShared::preload_classes(const char* class_list_path, TRAPS) {
1722 ClassListParser parser(class_list_path);
1723 int class_count = 0;
1724
1725 while (parser.parse_one_line()) {
1726 Klass* klass = ClassLoaderExt::load_one_class(&parser, THREAD);
1727 if (HAS_PENDING_EXCEPTION) {
1728 if (klass == NULL &&
1729 (PENDING_EXCEPTION->klass()->name() == vmSymbols::java_lang_ClassNotFoundException())) {
1730 // print a warning only when the pending exception is class not found
1731 tty->print_cr("Preload Warning: Cannot find %s", parser.current_class_name());
1732 }
1733 CLEAR_PENDING_EXCEPTION;
1734 }
1735 if (klass != NULL) {
1736 if (log_is_enabled(Trace, cds)) {
1737 ResourceMark rm;
1738 log_trace(cds)("Shared spaces preloaded: %s", klass->external_name());
1739 }
1740
1741 if (klass->is_instance_klass()) {
1742 InstanceKlass* ik = InstanceKlass::cast(klass);
1743
1744 // Link the class to cause the bytecodes to be rewritten and the
1745 // cpcache to be created. The linking is done as soon as classes
1746 // are loaded in order that the related data structures (klass and
1747 // cpCache) are located together.
1748 try_link_class(ik, THREAD);
1749 guarantee(!HAS_PENDING_EXCEPTION, "exception in link_class");
1750 }
1751
1752 class_count++;
1753 }
1754 }
1755
1756 return class_count;
1757 }
1758
1759 // Returns true if the class's status has changed
1760 bool MetaspaceShared::try_link_class(InstanceKlass* ik, TRAPS) {
1761 assert(DumpSharedSpaces, "should only be called during dumping");
1762 if (ik->init_state() < InstanceKlass::linked) {
1763 bool saved = BytecodeVerificationLocal;
1764 if (ik->loader_type() == 0 && ik->class_loader() == NULL) {
1765 // The verification decision is based on BytecodeVerificationRemote
1766 // for non-system classes. Since we are using the NULL classloader
1767 // to load non-system classes for customized class loaders during dumping,
1768 // we need to temporarily change BytecodeVerificationLocal to be the same as
1769 // BytecodeVerificationRemote. Note this can cause the parent system
1770 // classes also being verified. The extra overhead is acceptable during
1771 // dumping.
1772 BytecodeVerificationLocal = BytecodeVerificationRemote;
1773 }
1774 ik->link_class(THREAD);
1775 if (HAS_PENDING_EXCEPTION) {
1776 ResourceMark rm;
1777 tty->print_cr("Preload Warning: Verification failed for %s",
1778 ik->external_name());
1779 CLEAR_PENDING_EXCEPTION;
1780 ik->set_in_error_state();
1781 _has_error_classes = true;
1782 }
1783 BytecodeVerificationLocal = saved;
1784 return true;
1785 } else {
1786 return false;
1787 }
1788 }
1789
1790 #if INCLUDE_CDS_JAVA_HEAP
1791 void VM_PopulateDumpSharedSpace::dump_java_heap_objects() {
1792 if (!MetaspaceShared::is_heap_object_archiving_allowed()) {
1793 if (log_is_enabled(Info, cds)) {
1794 log_info(cds)(
1795 "Archived java heap is not supported as UseG1GC, "
1796 "UseCompressedOops and UseCompressedClassPointers are required."
1797 "Current settings: UseG1GC=%s, UseCompressedOops=%s, UseCompressedClassPointers=%s.",
1798 BOOL_TO_STR(UseG1GC), BOOL_TO_STR(UseCompressedOops),
1799 BOOL_TO_STR(UseCompressedClassPointers));
1800 }
1801 return;
1802 }
1803
1804 {
1805 NoSafepointVerifier nsv;
1806
1807 // Cache for recording where the archived objects are copied to
1808 MetaspaceShared::create_archive_object_cache();
1809
1810 tty->print_cr("Dumping objects to closed archive heap region ...");
1811 NOT_PRODUCT(StringTable::verify());
1812 // The closed space has maximum two regions. See FileMapInfo::write_archive_heap_regions() for details.
1813 _closed_archive_heap_regions = new GrowableArray<MemRegion>(2);
1814 MetaspaceShared::dump_closed_archive_heap_objects(_closed_archive_heap_regions);
1815
1816 tty->print_cr("Dumping objects to open archive heap region ...");
1817 _open_archive_heap_regions = new GrowableArray<MemRegion>(2);
1818 MetaspaceShared::dump_open_archive_heap_objects(_open_archive_heap_regions);
1819
1820 MetaspaceShared::destroy_archive_object_cache();
1821 }
1822
1823 G1HeapVerifier::verify_archive_regions();
1824 }
1825
1826 void VM_PopulateDumpSharedSpace::dump_archive_heap_oopmaps() {
1827 if (MetaspaceShared::is_heap_object_archiving_allowed()) {
1828 _closed_archive_heap_oopmaps = new GrowableArray<ArchiveHeapOopmapInfo>(2);
1829 dump_archive_heap_oopmaps(_closed_archive_heap_regions, _closed_archive_heap_oopmaps);
1830
1831 _open_archive_heap_oopmaps = new GrowableArray<ArchiveHeapOopmapInfo>(2);
1832 dump_archive_heap_oopmaps(_open_archive_heap_regions, _open_archive_heap_oopmaps);
1833 }
1834 }
1835
1836 void VM_PopulateDumpSharedSpace::dump_archive_heap_oopmaps(GrowableArray<MemRegion>* regions,
1837 GrowableArray<ArchiveHeapOopmapInfo>* oopmaps) {
1838 for (int i=0; i<regions->length(); i++) {
1839 ResourceBitMap oopmap = HeapShared::calculate_oopmap(regions->at(i));
1840 size_t size_in_bits = oopmap.size();
1841 size_t size_in_bytes = oopmap.size_in_bytes();
1842 uintptr_t* buffer = (uintptr_t*)_ro_region.allocate(size_in_bytes, sizeof(intptr_t));
1843 oopmap.write_to(buffer, size_in_bytes);
1844 log_info(cds)("Oopmap = " INTPTR_FORMAT " (" SIZE_FORMAT_W(6) " bytes) for heap region "
1845 INTPTR_FORMAT " (" SIZE_FORMAT_W(8) " bytes)",
1846 p2i(buffer), size_in_bytes,
1847 p2i(regions->at(i).start()), regions->at(i).byte_size());
1848
1849 ArchiveHeapOopmapInfo info;
1850 info._oopmap = (address)buffer;
1851 info._oopmap_size_in_bits = size_in_bits;
1852 oopmaps->append(info);
1853 }
1854 }
1855
1856 void MetaspaceShared::dump_closed_archive_heap_objects(
1857 GrowableArray<MemRegion> * closed_archive) {
1858 assert(is_heap_object_archiving_allowed(), "Cannot dump java heap objects");
1859
1860 Thread* THREAD = Thread::current();
1861 G1CollectedHeap::heap()->begin_archive_alloc_range();
1862
1863 // Archive interned string objects
1864 StringTable::write_to_archive();
1865
1866 G1CollectedHeap::heap()->end_archive_alloc_range(closed_archive,
1867 os::vm_allocation_granularity());
1868 }
1869
1870 void MetaspaceShared::dump_open_archive_heap_objects(
1871 GrowableArray<MemRegion> * open_archive) {
1872 assert(UseG1GC, "Only support G1 GC");
1873 assert(UseCompressedOops && UseCompressedClassPointers,
1874 "Only support UseCompressedOops and UseCompressedClassPointers enabled");
1875
1876 Thread* THREAD = Thread::current();
1877 G1CollectedHeap::heap()->begin_archive_alloc_range(true /* open */);
1878
1879 java_lang_Class::archive_basic_type_mirrors(THREAD);
1880
1881 MetaspaceShared::archive_klass_objects(THREAD);
1882
1883 HeapShared::archive_module_graph_objects(THREAD);
1884
1885 G1CollectedHeap::heap()->end_archive_alloc_range(open_archive,
1886 os::vm_allocation_granularity());
1887 }
1888
1889 unsigned MetaspaceShared::obj_hash(oop const& p) {
1890 assert(!p->mark()->has_bias_pattern(),
1891 "this object should never have been locked"); // so identity_hash won't safepoin
1892 unsigned hash = (unsigned)p->identity_hash();
1893 return hash;
1894 }
1895
1896 MetaspaceShared::ArchivedObjectCache* MetaspaceShared::_archive_object_cache = NULL;
1897 oop MetaspaceShared::find_archived_heap_object(oop obj) {
1898 assert(DumpSharedSpaces, "dump-time only");
1899 ArchivedObjectCache* cache = MetaspaceShared::archive_object_cache();
1900 oop* p = cache->get(obj);
1901 if (p != NULL) {
1902 return *p;
1903 } else {
1904 return NULL;
1905 }
1906 }
1907
1908 oop MetaspaceShared::archive_heap_object(oop obj, Thread* THREAD) {
1909 assert(DumpSharedSpaces, "dump-time only");
1910
1911 oop ao = find_archived_heap_object(obj);
1912 if (ao != NULL) {
1913 // already archived
1914 return ao;
1915 }
1916
1917 int len = obj->size();
1918 if (G1CollectedHeap::heap()->is_archive_alloc_too_large(len)) {
1919 log_debug(cds, heap)("Cannot archive, object (" PTR_FORMAT ") is too large: " SIZE_FORMAT,
1920 p2i(obj), (size_t)obj->size());
1921 return NULL;
1922 }
1923
1924 int hash = obj->identity_hash();
1925 oop archived_oop = (oop)G1CollectedHeap::heap()->archive_mem_allocate(len);
1926 if (archived_oop != NULL) {
1927 Copy::aligned_disjoint_words((HeapWord*)obj, (HeapWord*)archived_oop, len);
1928 relocate_klass_ptr(archived_oop);
1929 ArchivedObjectCache* cache = MetaspaceShared::archive_object_cache();
1930 cache->put(obj, archived_oop);
1931 log_debug(cds, heap)("Archived heap object " PTR_FORMAT " ==> " PTR_FORMAT,
1932 p2i(obj), p2i(archived_oop));
1933 } else {
1934 log_error(cds, heap)(
1935 "Cannot allocate space for object " PTR_FORMAT " in archived heap region",
1936 p2i(obj));
1937 vm_exit(1);
1938 }
1939 return archived_oop;
1940 }
1941
1942 oop MetaspaceShared::materialize_archived_object(narrowOop v) {
1943 if (!CompressedOops::is_null(v)) {
1944 oop obj = HeapShared::decode_with_archived_oop_encoding_mode(v);
1945 return G1CollectedHeap::heap()->materialize_archived_object(obj);
1946 }
1947 return NULL;
1948 }
1949
1950 void MetaspaceShared::archive_klass_objects(Thread* THREAD) {
1951 int i;
1952 for (i = 0; i < _global_klass_objects->length(); i++) {
1953 Klass* k = _global_klass_objects->at(i);
1954
1955 // archive mirror object
1956 java_lang_Class::archive_mirror(k, CHECK);
1957
1958 // archive the resolved_referenes array
1959 if (k->is_instance_klass()) {
1960 InstanceKlass* ik = InstanceKlass::cast(k);
1961 ik->constants()->archive_resolved_references(THREAD);
1962 }
1963 }
1964 }
1965
1966 bool MetaspaceShared::is_archive_object(oop p) {
1967 return (p == NULL) ? false : G1ArchiveAllocator::is_archive_object(p);
1968 }
1969
1970 void MetaspaceShared::fixup_mapped_heap_regions() {
1971 FileMapInfo *mapinfo = FileMapInfo::current_info();
1972 mapinfo->fixup_mapped_heap_regions();
1973 }
1974 #endif // INCLUDE_CDS_JAVA_HEAP
1975
1976 // Closure for serializing initialization data in from a data area
1977 // (ptr_array) read from the shared file.
1978
1979 class ReadClosure : public SerializeClosure {
1980 private:
1981 intptr_t** _ptr_array;
1982
1983 inline intptr_t nextPtr() {
1984 return *(*_ptr_array)++;
1985 }
1986
1987 public:
1988 ReadClosure(intptr_t** ptr_array) { _ptr_array = ptr_array; }
1989
1990 void do_ptr(void** p) {
1991 assert(*p == NULL, "initializing previous initialized pointer.");
1992 intptr_t obj = nextPtr();
1993 assert((intptr_t)obj >= 0 || (intptr_t)obj < -100,
1994 "hit tag while initializing ptrs.");
1995 *p = (void*)obj;
1996 }
1997
1998 void do_u4(u4* p) {
1999 intptr_t obj = nextPtr();
2000 *p = (u4)(uintx(obj));
2001 }
2002
2003 void do_tag(int tag) {
2004 int old_tag;
2005 old_tag = (int)(intptr_t)nextPtr();
2006 // do_int(&old_tag);
2007 assert(tag == old_tag, "old tag doesn't match");
2008 FileMapInfo::assert_mark(tag == old_tag);
2009 }
2010
2011 void do_oop(oop *p) {
2012 narrowOop o = (narrowOop)nextPtr();
2013 if (o == 0 || !MetaspaceShared::open_archive_heap_region_mapped()) {
2014 p = NULL;
2015 } else {
2016 assert(MetaspaceShared::is_heap_object_archiving_allowed(),
2017 "Archived heap object is not allowed");
2018 assert(MetaspaceShared::open_archive_heap_region_mapped(),
2019 "Open archive heap region is not mapped");
2020 *p = HeapShared::decode_with_archived_oop_encoding_mode(o);
2021 }
2022 }
2023
2024 void do_region(u_char* start, size_t size) {
2025 assert((intptr_t)start % sizeof(intptr_t) == 0, "bad alignment");
2026 assert(size % sizeof(intptr_t) == 0, "bad size");
2027 do_tag((int)size);
2028 while (size > 0) {
2029 *(intptr_t*)start = nextPtr();
2030 start += sizeof(intptr_t);
2031 size -= sizeof(intptr_t);
2032 }
2033 }
2034
2035 bool reading() const { return true; }
2036 };
2037
2038 // Return true if given address is in the misc data region
2039 bool MetaspaceShared::is_in_shared_region(const void* p, int idx) {
2040 return UseSharedSpaces && FileMapInfo::current_info()->is_in_shared_region(p, idx);
2041 }
2042
2043 bool MetaspaceShared::is_in_trampoline_frame(address addr) {
2044 if (UseSharedSpaces && is_in_shared_region(addr, MetaspaceShared::mc)) {
2045 return true;
2046 }
2047 return false;
2048 }
2049
2050 // Map shared spaces at requested addresses and return if succeeded.
2051 bool MetaspaceShared::map_shared_spaces(FileMapInfo* mapinfo) {
2052 size_t image_alignment = mapinfo->alignment();
2053
2054 #ifndef _WINDOWS
2055 // Map in the shared memory and then map the regions on top of it.
2056 // On Windows, don't map the memory here because it will cause the
2057 // mappings of the regions to fail.
2058 ReservedSpace shared_rs = mapinfo->reserve_shared_memory();
2059 if (!shared_rs.is_reserved()) return false;
2060 #endif
2061
2062 assert(!DumpSharedSpaces, "Should not be called with DumpSharedSpaces");
2063
2064 char* ro_base = NULL; char* ro_top;
2065 char* rw_base = NULL; char* rw_top;
2066 char* mc_base = NULL; char* mc_top;
2067 char* md_base = NULL; char* md_top;
2068 char* od_base = NULL; char* od_top;
2069
2070 // Map each shared region
2071 if ((mc_base = mapinfo->map_region(mc, &mc_top)) != NULL &&
2072 (rw_base = mapinfo->map_region(rw, &rw_top)) != NULL &&
2073 (ro_base = mapinfo->map_region(ro, &ro_top)) != NULL &&
2074 (md_base = mapinfo->map_region(md, &md_top)) != NULL &&
2075 (od_base = mapinfo->map_region(od, &od_top)) != NULL &&
2076 (image_alignment == (size_t)os::vm_allocation_granularity()) &&
2077 mapinfo->validate_shared_path_table()) {
2078 // Success -- set up MetaspaceObj::_shared_metaspace_{base,top} for
2079 // fast checking in MetaspaceShared::is_in_shared_metaspace() and
2080 // MetaspaceObj::is_shared().
2081 //
2082 // We require that mc->rw->ro->md->od to be laid out consecutively, with no
2083 // gaps between them. That way, we can ensure that the OS won't be able to
2084 // allocate any new memory spaces inside _shared_metaspace_{base,top}, which
2085 // would mess up the simple comparision in MetaspaceShared::is_in_shared_metaspace().
2086 assert(mc_base < ro_base && mc_base < rw_base && mc_base < md_base && mc_base < od_base, "must be");
2087 assert(od_top > ro_top && od_top > rw_top && od_top > md_top && od_top > mc_top , "must be");
2088 assert(mc_top == rw_base, "must be");
2089 assert(rw_top == ro_base, "must be");
2090 assert(ro_top == md_base, "must be");
2091 assert(md_top == od_base, "must be");
2092
2093 MetaspaceObj::_shared_metaspace_base = (void*)mc_base;
2094 MetaspaceObj::_shared_metaspace_top = (void*)od_top;
2095 return true;
2096 } else {
2097 // If there was a failure in mapping any of the spaces, unmap the ones
2098 // that succeeded
2099 if (ro_base != NULL) mapinfo->unmap_region(ro);
2100 if (rw_base != NULL) mapinfo->unmap_region(rw);
2101 if (mc_base != NULL) mapinfo->unmap_region(mc);
2102 if (md_base != NULL) mapinfo->unmap_region(md);
2103 if (od_base != NULL) mapinfo->unmap_region(od);
2104 #ifndef _WINDOWS
2105 // Release the entire mapped region
2106 shared_rs.release();
2107 #endif
2108 // If -Xshare:on is specified, print out the error message and exit VM,
2109 // otherwise, set UseSharedSpaces to false and continue.
2110 if (RequireSharedSpaces || PrintSharedArchiveAndExit) {
2111 vm_exit_during_initialization("Unable to use shared archive.", "Failed map_region for using -Xshare:on.");
2112 } else {
2113 FLAG_SET_DEFAULT(UseSharedSpaces, false);
2114 }
2115 return false;
2116 }
2117 }
2118
2119 // Read the miscellaneous data from the shared file, and
2120 // serialize it out to its various destinations.
2121
2122 void MetaspaceShared::initialize_shared_spaces() {
2123 FileMapInfo *mapinfo = FileMapInfo::current_info();
2124 _cds_i2i_entry_code_buffers = mapinfo->cds_i2i_entry_code_buffers();
2125 _cds_i2i_entry_code_buffers_size = mapinfo->cds_i2i_entry_code_buffers_size();
2126 _core_spaces_size = mapinfo->core_spaces_size();
2127 char* buffer = mapinfo->misc_data_patching_start();
2128 clone_cpp_vtables((intptr_t*)buffer);
2129
2130 // The rest of the data is now stored in the RW region
2131 buffer = mapinfo->read_only_tables_start();
2132 int sharedDictionaryLen = *(intptr_t*)buffer;
2133 buffer += sizeof(intptr_t);
2134 int number_of_entries = *(intptr_t*)buffer;
2135 buffer += sizeof(intptr_t);
2136 SystemDictionary::set_shared_dictionary((HashtableBucket<mtClass>*)buffer,
2137 sharedDictionaryLen,
2138 number_of_entries);
2139 buffer += sharedDictionaryLen;
2140
2141 // The following data are the linked list elements
2142 // (HashtableEntry objects) for the shared dictionary table.
2143
2144 int len = *(intptr_t*)buffer; // skip over shared dictionary entries
2145 buffer += sizeof(intptr_t);
2146 buffer += len;
2147
2148 // The table of archived java heap object sub-graph infos
2149 buffer = HeapShared::read_archived_subgraph_infos(buffer);
2150
2151 // Verify various attributes of the archive, plus initialize the
2152 // shared string/symbol tables
2153 intptr_t* array = (intptr_t*)buffer;
2154 ReadClosure rc(&array);
2155 serialize(&rc);
2156
2157 // Initialize the run-time symbol table.
2158 SymbolTable::create_table();
2159
2160 mapinfo->patch_archived_heap_embedded_pointers();
2161
2162 // Close the mapinfo file
2163 mapinfo->close();
2164
2165 if (PrintSharedArchiveAndExit) {
2166 if (PrintSharedDictionary) {
2167 tty->print_cr("\nShared classes:\n");
2168 SystemDictionary::print_shared(tty);
2169 }
2170 if (_archive_loading_failed) {
2171 tty->print_cr("archive is invalid");
2172 vm_exit(1);
2173 } else {
2174 tty->print_cr("archive is valid");
2175 vm_exit(0);
2176 }
2177 }
2178 }
2179
2180 // JVM/TI RedefineClasses() support:
2181 bool MetaspaceShared::remap_shared_readonly_as_readwrite() {
2182 assert(SafepointSynchronize::is_at_safepoint(), "must be at safepoint");
2183
2184 if (UseSharedSpaces) {
2185 // remap the shared readonly space to shared readwrite, private
2186 FileMapInfo* mapinfo = FileMapInfo::current_info();
2187 if (!mapinfo->remap_shared_readonly_as_readwrite()) {
2188 return false;
2189 }
2190 _remapped_readwrite = true;
2191 }
2192 return true;
2193 }
2194
2195 void MetaspaceShared::report_out_of_space(const char* name, size_t needed_bytes) {
2196 // This is highly unlikely to happen on 64-bits because we have reserved a 4GB space.
2197 // On 32-bit we reserve only 256MB so you could run out of space with 100,000 classes
2198 // or so.
2199 _mc_region.print_out_of_space_msg(name, needed_bytes);
2200 _rw_region.print_out_of_space_msg(name, needed_bytes);
2201 _ro_region.print_out_of_space_msg(name, needed_bytes);
2202 _md_region.print_out_of_space_msg(name, needed_bytes);
2203 _od_region.print_out_of_space_msg(name, needed_bytes);
2204
2205 vm_exit_during_initialization(err_msg("Unable to allocate from '%s' region", name),
2206 "Please reduce the number of shared classes.");
2207 }