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.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/vmOperations.hpp"
63 #include "utilities/align.hpp"
64 #include "utilities/defaultStream.hpp"
65 #include "utilities/hashtable.inline.hpp"
66 #if INCLUDE_G1GC
67 #include "gc/g1/g1Allocator.inline.hpp"
68 #include "gc/g1/g1CollectedHeap.hpp"
69 #endif
70
71 ReservedSpace MetaspaceShared::_shared_rs;
72 VirtualSpace MetaspaceShared::_shared_vs;
73 MetaspaceSharedStats MetaspaceShared::_stats;
74 bool MetaspaceShared::_has_error_classes;
75 bool MetaspaceShared::_archive_loading_failed = false;
76 bool MetaspaceShared::_remapped_readwrite = false;
77 bool MetaspaceShared::_open_archive_heap_region_mapped = false;
78 address MetaspaceShared::_cds_i2i_entry_code_buffers = NULL;
79 size_t MetaspaceShared::_cds_i2i_entry_code_buffers_size = 0;
80 size_t MetaspaceShared::_core_spaces_size = 0;
81
82 // The CDS archive is divided into the following regions:
83 // mc - misc code (the method entry trampolines)
84 // rw - read-write metadata
85 // ro - read-only metadata and read-only tables
86 // md - misc data (the c++ vtables)
87 // od - optional data (original class files)
88 //
89 // s0 - shared strings(closed archive heap space) #0
90 // s1 - shared strings(closed archive heap space) #1 (may be empty)
91 // oa0 - open archive heap space #0
92 // oa1 - open archive heap space #1 (may be empty)
93 //
94 // The mc, rw, ro, md and od regions are linearly allocated, starting from
95 // SharedBaseAddress, in the order of mc->rw->ro->md->od. The size of these 5 regions
96 // are page-aligned, and there's no gap between any consecutive regions.
97 //
98 // These 5 regions are populated in the following steps:
99 // [1] All classes are loaded in MetaspaceShared::preload_classes(). All metadata are
100 // temporarily allocated outside of the shared regions. Only the method entry
101 // trampolines are written into the mc region.
102 // [2] ArchiveCompactor copies RW metadata into the rw region.
103 // [3] ArchiveCompactor copies RO metadata into the ro region.
104 // [4] SymbolTable, StringTable, SystemDictionary, and a few other read-only data
105 // are copied into the ro region as read-only tables.
106 // [5] C++ vtables are copied into the md region.
107 // [6] Original class files are copied into the od region.
108 //
109 // The s0/s1 and oa0/oa1 regions are populated inside MetaspaceShared::dump_java_heap_objects.
110 // Their layout is independent of the other 5 regions.
111
112 class DumpRegion {
113 private:
114 const char* _name;
115 char* _base;
116 char* _top;
117 char* _end;
118 bool _is_packed;
119
120 char* expand_top_to(char* newtop) {
121 assert(is_allocatable(), "must be initialized and not packed");
122 assert(newtop >= _top, "must not grow backwards");
123 if (newtop > _end) {
124 MetaspaceShared::report_out_of_space(_name, newtop - _top);
125 ShouldNotReachHere();
126 }
127 MetaspaceShared::commit_shared_space_to(newtop);
128 _top = newtop;
129 return _top;
130 }
131
132 public:
133 DumpRegion(const char* name) : _name(name), _base(NULL), _top(NULL), _end(NULL), _is_packed(false) {}
134
135 char* allocate(size_t num_bytes, size_t alignment=BytesPerWord) {
136 char* p = (char*)align_up(_top, alignment);
137 char* newtop = p + align_up(num_bytes, alignment);
138 expand_top_to(newtop);
139 memset(p, 0, newtop - p);
140 return p;
141 }
142
143 void append_intptr_t(intptr_t n) {
144 assert(is_aligned(_top, sizeof(intptr_t)), "bad alignment");
145 intptr_t *p = (intptr_t*)_top;
146 char* newtop = _top + sizeof(intptr_t);
147 expand_top_to(newtop);
148 *p = n;
149 }
150
151 char* base() const { return _base; }
152 char* top() const { return _top; }
153 char* end() const { return _end; }
154 size_t reserved() const { return _end - _base; }
155 size_t used() const { return _top - _base; }
156 bool is_packed() const { return _is_packed; }
157 bool is_allocatable() const {
158 return !is_packed() && _base != NULL;
159 }
160
161 void print(size_t total_bytes) const {
162 tty->print_cr("%-3s space: " SIZE_FORMAT_W(9) " [ %4.1f%% of total] out of " SIZE_FORMAT_W(9) " bytes [%5.1f%% used] at " INTPTR_FORMAT,
163 _name, used(), percent_of(used(), total_bytes), reserved(), percent_of(used(), reserved()), p2i(_base));
164 }
165 void print_out_of_space_msg(const char* failing_region, size_t needed_bytes) {
166 tty->print("[%-8s] " PTR_FORMAT " - " PTR_FORMAT " capacity =%9d, allocated =%9d",
167 _name, p2i(_base), p2i(_top), int(_end - _base), int(_top - _base));
168 if (strcmp(_name, failing_region) == 0) {
169 tty->print_cr(" required = %d", int(needed_bytes));
170 } else {
171 tty->cr();
172 }
173 }
174
175 void init(const ReservedSpace* rs) {
176 _base = _top = rs->base();
177 _end = rs->end();
178 }
179 void init(char* b, char* t, char* e) {
180 _base = b;
181 _top = t;
182 _end = e;
183 }
184
185 void pack(DumpRegion* next = NULL) {
186 assert(!is_packed(), "sanity");
187 _end = (char*)align_up(_top, Metaspace::reserve_alignment());
188 _is_packed = true;
189 if (next != NULL) {
190 next->_base = next->_top = this->_end;
191 next->_end = MetaspaceShared::shared_rs()->end();
192 }
193 }
194 bool contains(char* p) {
195 return base() <= p && p < top();
196 }
197 };
198
199
200 DumpRegion _mc_region("mc"), _ro_region("ro"), _rw_region("rw"), _md_region("md"), _od_region("od");
201 size_t _total_string_region_size = 0, _total_open_archive_region_size = 0;
202
203 char* MetaspaceShared::misc_code_space_alloc(size_t num_bytes) {
204 return _mc_region.allocate(num_bytes);
205 }
206
207 char* MetaspaceShared::read_only_space_alloc(size_t num_bytes) {
208 return _ro_region.allocate(num_bytes);
209 }
210
211 char* MetaspaceShared::read_only_space_top() {
212 return _ro_region.top();
213 }
214
215 void MetaspaceShared::initialize_runtime_shared_and_meta_spaces() {
216 assert(UseSharedSpaces, "Must be called when UseSharedSpaces is enabled");
217
218 // If using shared space, open the file that contains the shared space
219 // and map in the memory before initializing the rest of metaspace (so
220 // the addresses don't conflict)
221 address cds_address = NULL;
222 FileMapInfo* mapinfo = new FileMapInfo();
223
224 // Open the shared archive file, read and validate the header. If
225 // initialization fails, shared spaces [UseSharedSpaces] are
226 // disabled and the file is closed.
227 // Map in spaces now also
228 if (mapinfo->initialize() && map_shared_spaces(mapinfo)) {
229 size_t cds_total = core_spaces_size();
230 cds_address = (address)mapinfo->header()->region_addr(0);
231 #ifdef _LP64
232 if (Metaspace::using_class_space()) {
233 char* cds_end = (char*)(cds_address + cds_total);
234 cds_end = (char *)align_up(cds_end, Metaspace::reserve_alignment());
235 // If UseCompressedClassPointers is set then allocate the metaspace area
236 // above the heap and above the CDS area (if it exists).
237 Metaspace::allocate_metaspace_compressed_klass_ptrs(cds_end, cds_address);
238 // map_heap_regions() compares the current narrow oop and klass encodings
239 // with the archived ones, so it must be done after all encodings are determined.
240 mapinfo->map_heap_regions();
241 }
242 Universe::set_narrow_klass_range(CompressedClassSpaceSize);
243 #endif // _LP64
244 } else {
245 assert(!mapinfo->is_open() && !UseSharedSpaces,
246 "archive file not closed or shared spaces not disabled.");
247 }
248 }
249
250 void MetaspaceShared::initialize_dumptime_shared_and_meta_spaces() {
251 assert(DumpSharedSpaces, "should be called for dump time only");
252 const size_t reserve_alignment = Metaspace::reserve_alignment();
253 bool large_pages = false; // No large pages when dumping the CDS archive.
254 char* shared_base = (char*)align_up((char*)SharedBaseAddress, reserve_alignment);
255
256 #ifdef _LP64
257 // On 64-bit VM, the heap and class space layout will be the same as if
258 // you're running in -Xshare:on mode:
259 //
260 // +-- SharedBaseAddress (default = 0x800000000)
261 // v
262 // +-..---------+---------+ ... +----+----+----+----+----+---------------+
263 // | Heap | Archive | | MC | RW | RO | MD | OD | class space |
264 // +-..---------+---------+ ... +----+----+----+----+----+---------------+
265 // |<-- MaxHeapSize -->| |<-- UnscaledClassSpaceMax = 4GB ------->|
266 //
267 const uint64_t UnscaledClassSpaceMax = (uint64_t(max_juint) + 1);
268 const size_t cds_total = align_down(UnscaledClassSpaceMax, reserve_alignment);
269 #else
270 // We don't support archives larger than 256MB on 32-bit due to limited virtual address space.
271 size_t cds_total = align_down(256*M, reserve_alignment);
272 #endif
273
274 // First try to reserve the space at the specified SharedBaseAddress.
275 _shared_rs = ReservedSpace(cds_total, reserve_alignment, large_pages, shared_base);
276 if (_shared_rs.is_reserved()) {
277 assert(shared_base == 0 || _shared_rs.base() == shared_base, "should match");
278 } else {
279 // Get a mmap region anywhere if the SharedBaseAddress fails.
280 _shared_rs = ReservedSpace(cds_total, reserve_alignment, large_pages);
281 }
282 if (!_shared_rs.is_reserved()) {
283 vm_exit_during_initialization("Unable to reserve memory for shared space",
284 err_msg(SIZE_FORMAT " bytes.", cds_total));
285 }
286
287 #ifdef _LP64
288 // During dump time, we allocate 4GB (UnscaledClassSpaceMax) of space and split it up:
289 // + The upper 1 GB is used as the "temporary compressed class space" -- preload_classes()
290 // will store Klasses into this space.
291 // + The lower 3 GB is used for the archive -- when preload_classes() is done,
292 // ArchiveCompactor will copy the class metadata into this space, first the RW parts,
293 // then the RO parts.
294
295 assert(UseCompressedOops && UseCompressedClassPointers,
296 "UseCompressedOops and UseCompressedClassPointers must be set");
297
298 size_t max_archive_size = align_down(cds_total * 3 / 4, reserve_alignment);
299 ReservedSpace tmp_class_space = _shared_rs.last_part(max_archive_size);
300 CompressedClassSpaceSize = align_down(tmp_class_space.size(), reserve_alignment);
301 _shared_rs = _shared_rs.first_part(max_archive_size);
302
303 // Set up compress class pointers.
304 Universe::set_narrow_klass_base((address)_shared_rs.base());
305 // Set narrow_klass_shift to be LogKlassAlignmentInBytes. This is consistent
306 // with AOT.
307 Universe::set_narrow_klass_shift(LogKlassAlignmentInBytes);
308 // Set the range of klass addresses to 4GB.
309 Universe::set_narrow_klass_range(cds_total);
310
311 Metaspace::initialize_class_space(tmp_class_space);
312 tty->print_cr("narrow_klass_base = " PTR_FORMAT ", narrow_klass_shift = %d",
313 p2i(Universe::narrow_klass_base()), Universe::narrow_klass_shift());
314
315 tty->print_cr("Allocated temporary class space: " SIZE_FORMAT " bytes at " PTR_FORMAT,
316 CompressedClassSpaceSize, p2i(tmp_class_space.base()));
317 #endif
318
319 // Start with 0 committed bytes. The memory will be committed as needed by
320 // MetaspaceShared::commit_shared_space_to().
321 if (!_shared_vs.initialize(_shared_rs, 0)) {
322 vm_exit_during_initialization("Unable to allocate memory for shared space");
323 }
324
325 _mc_region.init(&_shared_rs);
326 tty->print_cr("Allocated shared space: " SIZE_FORMAT " bytes at " PTR_FORMAT,
327 _shared_rs.size(), p2i(_shared_rs.base()));
328 }
329
330 // Called by universe_post_init()
331 void MetaspaceShared::post_initialize(TRAPS) {
332 if (UseSharedSpaces) {
333 int size = FileMapInfo::get_number_of_shared_paths();
334 if (size > 0) {
335 SystemDictionaryShared::allocate_shared_data_arrays(size, THREAD);
336 FileMapHeader* header = FileMapInfo::current_info()->header();
337 ClassLoaderExt::init_paths_start_index(header->_app_class_paths_start_index);
338 ClassLoaderExt::init_app_module_paths_start_index(header->_app_module_paths_start_index);
339 }
340 }
341
342 if (DumpSharedSpaces) {
343 if (SharedArchiveConfigFile) {
344 read_extra_data(SharedArchiveConfigFile, THREAD);
345 }
346 }
347 }
348
349 void MetaspaceShared::read_extra_data(const char* filename, TRAPS) {
350 HashtableTextDump reader(filename);
351 reader.check_version("VERSION: 1.0");
352
353 while (reader.remain() > 0) {
354 int utf8_length;
355 int prefix_type = reader.scan_prefix(&utf8_length);
356 ResourceMark rm(THREAD);
357 char* utf8_buffer = NEW_RESOURCE_ARRAY(char, utf8_length);
358 reader.get_utf8(utf8_buffer, utf8_length);
359
360 if (prefix_type == HashtableTextDump::SymbolPrefix) {
361 SymbolTable::new_symbol(utf8_buffer, utf8_length, THREAD);
362 } else{
363 assert(prefix_type == HashtableTextDump::StringPrefix, "Sanity");
364 utf8_buffer[utf8_length] = '\0';
365 oop s = StringTable::intern(utf8_buffer, THREAD);
366 }
367 }
368 }
369
370 void MetaspaceShared::commit_shared_space_to(char* newtop) {
371 assert(DumpSharedSpaces, "dump-time only");
372 char* base = _shared_rs.base();
373 size_t need_committed_size = newtop - base;
374 size_t has_committed_size = _shared_vs.committed_size();
375 if (need_committed_size < has_committed_size) {
376 return;
377 }
378
379 size_t min_bytes = need_committed_size - has_committed_size;
380 size_t preferred_bytes = 1 * M;
381 size_t uncommitted = _shared_vs.reserved_size() - has_committed_size;
382
383 size_t commit = MAX2(min_bytes, preferred_bytes);
384 assert(commit <= uncommitted, "sanity");
385
386 bool result = _shared_vs.expand_by(commit, false);
387 if (!result) {
388 vm_exit_during_initialization(err_msg("Failed to expand shared space to " SIZE_FORMAT " bytes",
389 need_committed_size));
390 }
391
392 log_info(cds)("Expanding shared spaces by " SIZE_FORMAT_W(7) " bytes [total " SIZE_FORMAT_W(9) " bytes ending at %p]",
393 commit, _shared_vs.actual_committed_size(), _shared_vs.high());
394 }
395
396 // Read/write a data stream for restoring/preserving metadata pointers and
397 // miscellaneous data from/to the shared archive file.
398
399 void MetaspaceShared::serialize(SerializeClosure* soc) {
400 int tag = 0;
401 soc->do_tag(--tag);
402
403 // Verify the sizes of various metadata in the system.
404 soc->do_tag(sizeof(Method));
405 soc->do_tag(sizeof(ConstMethod));
406 soc->do_tag(arrayOopDesc::base_offset_in_bytes(T_BYTE));
407 soc->do_tag(sizeof(ConstantPool));
408 soc->do_tag(sizeof(ConstantPoolCache));
409 soc->do_tag(objArrayOopDesc::base_offset_in_bytes());
410 soc->do_tag(typeArrayOopDesc::base_offset_in_bytes(T_BYTE));
411 soc->do_tag(sizeof(Symbol));
412
413 // Dump/restore miscellaneous metadata.
414 Universe::serialize(soc, true);
415 soc->do_tag(--tag);
416
417 // Dump/restore references to commonly used names and signatures.
418 vmSymbols::serialize(soc);
419 soc->do_tag(--tag);
420
421 // Dump/restore the symbol and string tables
422 SymbolTable::serialize(soc);
423 StringTable::serialize(soc);
424 soc->do_tag(--tag);
425
426 JavaClasses::serialize_offsets(soc);
427 soc->do_tag(--tag);
428
429 soc->do_tag(666);
430 }
431
432 address MetaspaceShared::cds_i2i_entry_code_buffers(size_t total_size) {
433 if (DumpSharedSpaces) {
434 if (_cds_i2i_entry_code_buffers == NULL) {
435 _cds_i2i_entry_code_buffers = (address)misc_code_space_alloc(total_size);
436 _cds_i2i_entry_code_buffers_size = total_size;
437 }
438 } else if (UseSharedSpaces) {
439 assert(_cds_i2i_entry_code_buffers != NULL, "must already been initialized");
440 } else {
441 return NULL;
442 }
443
444 assert(_cds_i2i_entry_code_buffers_size == total_size, "must not change");
445 return _cds_i2i_entry_code_buffers;
446 }
447
448 // CDS code for dumping shared archive.
449
450 // Global object for holding classes that have been loaded. Since this
451 // is run at a safepoint just before exit, this is the entire set of classes.
452 static GrowableArray<Klass*>* _global_klass_objects;
453
454 static void collect_array_classes(Klass* k) {
455 _global_klass_objects->append_if_missing(k);
456 if (k->is_array_klass()) {
457 // Add in the array classes too
458 ArrayKlass* ak = ArrayKlass::cast(k);
459 Klass* h = ak->higher_dimension();
460 if (h != NULL) {
461 h->array_klasses_do(collect_array_classes);
462 }
463 }
464 }
465
466 class CollectClassesClosure : public KlassClosure {
467 void do_klass(Klass* k) {
468 if (!(k->is_instance_klass() && InstanceKlass::cast(k)->is_in_error_state())) {
469 if (k->is_instance_klass() && InstanceKlass::cast(k)->signers() != NULL) {
470 // Mark any class with signers and don't add to the _global_klass_objects
471 k->set_has_signer_and_not_archived();
472 } else {
473 _global_klass_objects->append_if_missing(k);
474 }
475 }
476 if (k->is_array_klass()) {
477 // Add in the array classes too
478 ArrayKlass* ak = ArrayKlass::cast(k);
479 Klass* h = ak->higher_dimension();
480 if (h != NULL) {
481 h->array_klasses_do(collect_array_classes);
482 }
483 }
484 }
485 };
486
487 static void remove_unshareable_in_classes() {
488 for (int i = 0; i < _global_klass_objects->length(); i++) {
489 Klass* k = _global_klass_objects->at(i);
490 if (!k->is_objArray_klass()) {
491 // InstanceKlass and TypeArrayKlass will in turn call remove_unshareable_info
492 // on their array classes.
493 assert(k->is_instance_klass() || k->is_typeArray_klass(), "must be");
494 k->remove_unshareable_info();
495 }
496 }
497 }
498
499 static void remove_java_mirror_in_classes() {
500 for (int i = 0; i < _global_klass_objects->length(); i++) {
501 Klass* k = _global_klass_objects->at(i);
502 if (!k->is_objArray_klass()) {
503 // InstanceKlass and TypeArrayKlass will in turn call remove_unshareable_info
504 // on their array classes.
505 assert(k->is_instance_klass() || k->is_typeArray_klass(), "must be");
506 k->remove_java_mirror();
507 }
508 }
509 }
510
511 static void clear_basic_type_mirrors() {
512 assert(!MetaspaceShared::is_heap_object_archiving_allowed(), "Sanity");
513 Universe::set_int_mirror(NULL);
514 Universe::set_float_mirror(NULL);
515 Universe::set_double_mirror(NULL);
516 Universe::set_byte_mirror(NULL);
517 Universe::set_bool_mirror(NULL);
518 Universe::set_char_mirror(NULL);
519 Universe::set_long_mirror(NULL);
520 Universe::set_short_mirror(NULL);
521 Universe::set_void_mirror(NULL);
522 }
523
524 static void rewrite_nofast_bytecode(Method* method) {
525 BytecodeStream bcs(method);
526 while (!bcs.is_last_bytecode()) {
527 Bytecodes::Code opcode = bcs.next();
528 switch (opcode) {
529 case Bytecodes::_getfield: *bcs.bcp() = Bytecodes::_nofast_getfield; break;
530 case Bytecodes::_putfield: *bcs.bcp() = Bytecodes::_nofast_putfield; break;
531 case Bytecodes::_aload_0: *bcs.bcp() = Bytecodes::_nofast_aload_0; break;
532 case Bytecodes::_iload: {
533 if (!bcs.is_wide()) {
534 *bcs.bcp() = Bytecodes::_nofast_iload;
535 }
536 break;
537 }
538 default: break;
539 }
540 }
541 }
542
543 // Walk all methods in the class list to ensure that they won't be modified at
544 // run time. This includes:
545 // [1] Rewrite all bytecodes as needed, so that the ConstMethod* will not be modified
546 // at run time by RewriteBytecodes/RewriteFrequentPairs
547 // [2] Assign a fingerprint, so one doesn't need to be assigned at run-time.
548 static void rewrite_nofast_bytecodes_and_calculate_fingerprints() {
549 for (int i = 0; i < _global_klass_objects->length(); i++) {
550 Klass* k = _global_klass_objects->at(i);
551 if (k->is_instance_klass()) {
552 InstanceKlass* ik = InstanceKlass::cast(k);
553 for (int i = 0; i < ik->methods()->length(); i++) {
554 Method* m = ik->methods()->at(i);
555 rewrite_nofast_bytecode(m);
556 Fingerprinter fp(m);
557 // The side effect of this call sets method's fingerprint field.
558 fp.fingerprint();
559 }
560 }
561 }
562 }
563
564 static void relocate_cached_class_file() {
565 for (int i = 0; i < _global_klass_objects->length(); i++) {
566 Klass* k = _global_klass_objects->at(i);
567 if (k->is_instance_klass()) {
568 InstanceKlass* ik = InstanceKlass::cast(k);
569 JvmtiCachedClassFileData* p = ik->get_archived_class_data();
570 if (p != NULL) {
571 int size = offset_of(JvmtiCachedClassFileData, data) + p->length;
572 JvmtiCachedClassFileData* q = (JvmtiCachedClassFileData*)_od_region.allocate(size);
573 q->length = p->length;
574 memcpy(q->data, p->data, p->length);
575 ik->set_archived_class_data(q);
576 }
577 }
578 }
579 }
580
581 NOT_PRODUCT(
582 static void assert_not_anonymous_class(InstanceKlass* k) {
583 assert(!(k->is_anonymous()), "cannot archive anonymous classes");
584 }
585
586 // Anonymous classes are not stored inside any dictionaries. They are created by
587 // SystemDictionary::parse_stream() with a non-null host_klass.
588 static void assert_no_anonymoys_classes_in_dictionaries() {
589 ClassLoaderDataGraph::dictionary_classes_do(assert_not_anonymous_class);
590 })
591
592 // Objects of the Metadata types (such as Klass and ConstantPool) have C++ vtables.
593 // (In GCC this is the field <Type>::_vptr, i.e., first word in the object.)
594 //
595 // Addresses of the vtables and the methods may be different across JVM runs,
596 // if libjvm.so is dynamically loaded at a different base address.
597 //
598 // To ensure that the Metadata objects in the CDS archive always have the correct vtable:
599 //
600 // + at dump time: we redirect the _vptr to point to our own vtables inside
601 // the CDS image
602 // + at run time: we clone the actual contents of the vtables from libjvm.so
603 // into our own tables.
604
605 // Currently, the archive contain ONLY the following types of objects that have C++ vtables.
606 #define CPP_VTABLE_PATCH_TYPES_DO(f) \
607 f(ConstantPool) \
608 f(InstanceKlass) \
609 f(InstanceClassLoaderKlass) \
610 f(InstanceMirrorKlass) \
611 f(InstanceRefKlass) \
612 f(Method) \
613 f(ObjArrayKlass) \
614 f(TypeArrayKlass)
615
616 class CppVtableInfo {
617 intptr_t _vtable_size;
618 intptr_t _cloned_vtable[1];
619 public:
620 static int num_slots(int vtable_size) {
621 return 1 + vtable_size; // Need to add the space occupied by _vtable_size;
622 }
623 int vtable_size() { return int(uintx(_vtable_size)); }
624 void set_vtable_size(int n) { _vtable_size = intptr_t(n); }
625 intptr_t* cloned_vtable() { return &_cloned_vtable[0]; }
626 void zero() { memset(_cloned_vtable, 0, sizeof(intptr_t) * vtable_size()); }
627 // Returns the address of the next CppVtableInfo that can be placed immediately after this CppVtableInfo
628 static size_t byte_size(int vtable_size) {
629 CppVtableInfo i;
630 return pointer_delta(&i._cloned_vtable[vtable_size], &i, sizeof(u1));
631 }
632 };
633
634 template <class T> class CppVtableCloner : public T {
635 static intptr_t* vtable_of(Metadata& m) {
636 return *((intptr_t**)&m);
637 }
638 static CppVtableInfo* _info;
639
640 static int get_vtable_length(const char* name);
641
642 public:
643 // Allocate and initialize the C++ vtable, starting from top, but do not go past end.
644 static intptr_t* allocate(const char* name);
645
646 // Clone the vtable to ...
647 static intptr_t* clone_vtable(const char* name, CppVtableInfo* info);
648
649 static void zero_vtable_clone() {
650 assert(DumpSharedSpaces, "dump-time only");
651 _info->zero();
652 }
653
654 // Switch the vtable pointer to point to the cloned vtable.
655 static void patch(Metadata* obj) {
656 assert(DumpSharedSpaces, "dump-time only");
657 *(void**)obj = (void*)(_info->cloned_vtable());
658 }
659
660 static bool is_valid_shared_object(const T* obj) {
661 intptr_t* vptr = *(intptr_t**)obj;
662 return vptr == _info->cloned_vtable();
663 }
664 };
665
666 template <class T> CppVtableInfo* CppVtableCloner<T>::_info = NULL;
667
668 template <class T>
669 intptr_t* CppVtableCloner<T>::allocate(const char* name) {
670 assert(is_aligned(_md_region.top(), sizeof(intptr_t)), "bad alignment");
671 int n = get_vtable_length(name);
672 _info = (CppVtableInfo*)_md_region.allocate(CppVtableInfo::byte_size(n), sizeof(intptr_t));
673 _info->set_vtable_size(n);
674
675 intptr_t* p = clone_vtable(name, _info);
676 assert((char*)p == _md_region.top(), "must be");
677
678 return p;
679 }
680
681 template <class T>
682 intptr_t* CppVtableCloner<T>::clone_vtable(const char* name, CppVtableInfo* info) {
683 if (!DumpSharedSpaces) {
684 assert(_info == 0, "_info is initialized only at dump time");
685 _info = info; // Remember it -- it will be used by MetaspaceShared::is_valid_shared_method()
686 }
687 T tmp; // Allocate temporary dummy metadata object to get to the original vtable.
688 int n = info->vtable_size();
689 intptr_t* srcvtable = vtable_of(tmp);
690 intptr_t* dstvtable = info->cloned_vtable();
691
692 // We already checked (and, if necessary, adjusted n) when the vtables were allocated, so we are
693 // safe to do memcpy.
694 log_debug(cds, vtables)("Copying %3d vtable entries for %s", n, name);
695 memcpy(dstvtable, srcvtable, sizeof(intptr_t) * n);
696 return dstvtable + n;
697 }
698
699 // To determine the size of the vtable for each type, we use the following
700 // trick by declaring 2 subclasses:
701 //
702 // class CppVtableTesterA: public InstanceKlass {virtual int last_virtual_method() {return 1;} };
703 // class CppVtableTesterB: public InstanceKlass {virtual void* last_virtual_method() {return NULL}; };
704 //
705 // CppVtableTesterA and CppVtableTesterB's vtables have the following properties:
706 // - Their size (N+1) is exactly one more than the size of InstanceKlass's vtable (N)
707 // - The first N entries have are exactly the same as in InstanceKlass's vtable.
708 // - Their last entry is different.
709 //
710 // So to determine the value of N, we just walk CppVtableTesterA and CppVtableTesterB's tables
711 // and find the first entry that's different.
712 //
713 // This works on all C++ compilers supported by Oracle, but you may need to tweak it for more
714 // esoteric compilers.
715
716 template <class T> class CppVtableTesterB: public T {
717 public:
718 virtual int last_virtual_method() {return 1;}
719 };
720
721 template <class T> class CppVtableTesterA : public T {
722 public:
723 virtual void* last_virtual_method() {
724 // Make this different than CppVtableTesterB::last_virtual_method so the C++
725 // compiler/linker won't alias the two functions.
726 return NULL;
727 }
728 };
729
730 template <class T>
731 int CppVtableCloner<T>::get_vtable_length(const char* name) {
732 CppVtableTesterA<T> a;
733 CppVtableTesterB<T> b;
734
735 intptr_t* avtable = vtable_of(a);
736 intptr_t* bvtable = vtable_of(b);
737
738 // Start at slot 1, because slot 0 may be RTTI (on Solaris/Sparc)
739 int vtable_len = 1;
740 for (; ; vtable_len++) {
741 if (avtable[vtable_len] != bvtable[vtable_len]) {
742 break;
743 }
744 }
745 log_debug(cds, vtables)("Found %3d vtable entries for %s", vtable_len, name);
746
747 return vtable_len;
748 }
749
750 #define ALLOC_CPP_VTABLE_CLONE(c) \
751 CppVtableCloner<c>::allocate(#c);
752
753 #define CLONE_CPP_VTABLE(c) \
754 p = CppVtableCloner<c>::clone_vtable(#c, (CppVtableInfo*)p);
755
756 #define ZERO_CPP_VTABLE(c) \
757 CppVtableCloner<c>::zero_vtable_clone();
758
759 // This can be called at both dump time and run time.
760 intptr_t* MetaspaceShared::clone_cpp_vtables(intptr_t* p) {
761 assert(DumpSharedSpaces || UseSharedSpaces, "sanity");
762 CPP_VTABLE_PATCH_TYPES_DO(CLONE_CPP_VTABLE);
763 return p;
764 }
765
766 void MetaspaceShared::zero_cpp_vtable_clones_for_writing() {
767 assert(DumpSharedSpaces, "dump-time only");
768 CPP_VTABLE_PATCH_TYPES_DO(ZERO_CPP_VTABLE);
769 }
770
771 // Allocate and initialize the C++ vtables, starting from top, but do not go past end.
772 void MetaspaceShared::allocate_cpp_vtable_clones() {
773 assert(DumpSharedSpaces, "dump-time only");
774 // Layout (each slot is a intptr_t):
775 // [number of slots in the first vtable = n1]
776 // [ <n1> slots for the first vtable]
777 // [number of slots in the first second = n2]
778 // [ <n2> slots for the second vtable]
779 // ...
780 // The order of the vtables is the same as the CPP_VTAB_PATCH_TYPES_DO macro.
781 CPP_VTABLE_PATCH_TYPES_DO(ALLOC_CPP_VTABLE_CLONE);
782 }
783
784 // Switch the vtable pointer to point to the cloned vtable. We assume the
785 // vtable pointer is in first slot in object.
786 void MetaspaceShared::patch_cpp_vtable_pointers() {
787 int n = _global_klass_objects->length();
788 for (int i = 0; i < n; i++) {
789 Klass* obj = _global_klass_objects->at(i);
790 if (obj->is_instance_klass()) {
791 InstanceKlass* ik = InstanceKlass::cast(obj);
792 if (ik->is_class_loader_instance_klass()) {
793 CppVtableCloner<InstanceClassLoaderKlass>::patch(ik);
794 } else if (ik->is_reference_instance_klass()) {
795 CppVtableCloner<InstanceRefKlass>::patch(ik);
796 } else if (ik->is_mirror_instance_klass()) {
797 CppVtableCloner<InstanceMirrorKlass>::patch(ik);
798 } else {
799 CppVtableCloner<InstanceKlass>::patch(ik);
800 }
801 ConstantPool* cp = ik->constants();
802 CppVtableCloner<ConstantPool>::patch(cp);
803 for (int j = 0; j < ik->methods()->length(); j++) {
804 Method* m = ik->methods()->at(j);
805 CppVtableCloner<Method>::patch(m);
806 assert(CppVtableCloner<Method>::is_valid_shared_object(m), "must be");
807 }
808 } else if (obj->is_objArray_klass()) {
809 CppVtableCloner<ObjArrayKlass>::patch(obj);
810 } else {
811 assert(obj->is_typeArray_klass(), "sanity");
812 CppVtableCloner<TypeArrayKlass>::patch(obj);
813 }
814 }
815 }
816
817 bool MetaspaceShared::is_valid_shared_method(const Method* m) {
818 assert(is_in_shared_metaspace(m), "must be");
819 return CppVtableCloner<Method>::is_valid_shared_object(m);
820 }
821
822 // Closure for serializing initialization data out to a data area to be
823 // written to the shared file.
824
825 class WriteClosure : public SerializeClosure {
826 private:
827 DumpRegion* _dump_region;
828
829 public:
830 WriteClosure(DumpRegion* r) {
831 _dump_region = r;
832 }
833
834 void do_ptr(void** p) {
835 _dump_region->append_intptr_t((intptr_t)*p);
836 }
837
838 void do_u4(u4* p) {
839 void* ptr = (void*)(uintx(*p));
840 do_ptr(&ptr);
841 }
842
843 void do_tag(int tag) {
844 _dump_region->append_intptr_t((intptr_t)tag);
845 }
846
847 void do_oop(oop* o) {
848 if (*o == NULL) {
849 _dump_region->append_intptr_t(0);
850 } else {
851 assert(MetaspaceShared::is_heap_object_archiving_allowed(),
852 "Archiving heap object is not allowed");
853 _dump_region->append_intptr_t(
854 (intptr_t)CompressedOops::encode_not_null(*o));
855 }
856 }
857
858 void do_region(u_char* start, size_t size) {
859 assert((intptr_t)start % sizeof(intptr_t) == 0, "bad alignment");
860 assert(size % sizeof(intptr_t) == 0, "bad size");
861 do_tag((int)size);
862 while (size > 0) {
863 _dump_region->append_intptr_t(*(intptr_t*)start);
864 start += sizeof(intptr_t);
865 size -= sizeof(intptr_t);
866 }
867 }
868
869 bool reading() const { return false; }
870 };
871
872 // This is for dumping detailed statistics for the allocations
873 // in the shared spaces.
874 class DumpAllocStats : public ResourceObj {
875 public:
876
877 // Here's poor man's enum inheritance
878 #define SHAREDSPACE_OBJ_TYPES_DO(f) \
879 METASPACE_OBJ_TYPES_DO(f) \
880 f(SymbolHashentry) \
881 f(SymbolBucket) \
882 f(StringHashentry) \
883 f(StringBucket) \
884 f(Other)
885
886 enum Type {
887 // Types are MetaspaceObj::ClassType, MetaspaceObj::SymbolType, etc
888 SHAREDSPACE_OBJ_TYPES_DO(METASPACE_OBJ_TYPE_DECLARE)
889 _number_of_types
890 };
891
892 static const char * type_name(Type type) {
893 switch(type) {
894 SHAREDSPACE_OBJ_TYPES_DO(METASPACE_OBJ_TYPE_NAME_CASE)
895 default:
896 ShouldNotReachHere();
897 return NULL;
898 }
899 }
900
901 public:
902 enum { RO = 0, RW = 1 };
903
904 int _counts[2][_number_of_types];
905 int _bytes [2][_number_of_types];
906
907 DumpAllocStats() {
908 memset(_counts, 0, sizeof(_counts));
909 memset(_bytes, 0, sizeof(_bytes));
910 };
911
912 void record(MetaspaceObj::Type type, int byte_size, bool read_only) {
913 assert(int(type) >= 0 && type < MetaspaceObj::_number_of_types, "sanity");
914 int which = (read_only) ? RO : RW;
915 _counts[which][type] ++;
916 _bytes [which][type] += byte_size;
917 }
918
919 void record_other_type(int byte_size, bool read_only) {
920 int which = (read_only) ? RO : RW;
921 _bytes [which][OtherType] += byte_size;
922 }
923 void print_stats(int ro_all, int rw_all, int mc_all, int md_all);
924 };
925
926 void DumpAllocStats::print_stats(int ro_all, int rw_all, int mc_all, int md_all) {
927 // Calculate size of data that was not allocated by Metaspace::allocate()
928 MetaspaceSharedStats *stats = MetaspaceShared::stats();
929
930 // symbols
931 _counts[RO][SymbolHashentryType] = stats->symbol.hashentry_count;
932 _bytes [RO][SymbolHashentryType] = stats->symbol.hashentry_bytes;
933
934 _counts[RO][SymbolBucketType] = stats->symbol.bucket_count;
935 _bytes [RO][SymbolBucketType] = stats->symbol.bucket_bytes;
936
937 // strings
938 _counts[RO][StringHashentryType] = stats->string.hashentry_count;
939 _bytes [RO][StringHashentryType] = stats->string.hashentry_bytes;
940
941 _counts[RO][StringBucketType] = stats->string.bucket_count;
942 _bytes [RO][StringBucketType] = stats->string.bucket_bytes;
943
944 // TODO: count things like dictionary, vtable, etc
945 _bytes[RW][OtherType] += mc_all + md_all;
946 rw_all += mc_all + md_all; // mc/md are mapped Read/Write
947
948 // prevent divide-by-zero
949 if (ro_all < 1) {
950 ro_all = 1;
951 }
952 if (rw_all < 1) {
953 rw_all = 1;
954 }
955
956 int all_ro_count = 0;
957 int all_ro_bytes = 0;
958 int all_rw_count = 0;
959 int all_rw_bytes = 0;
960
961 // To make fmt_stats be a syntactic constant (for format warnings), use #define.
962 #define fmt_stats "%-20s: %8d %10d %5.1f | %8d %10d %5.1f | %8d %10d %5.1f"
963 const char *sep = "--------------------+---------------------------+---------------------------+--------------------------";
964 const char *hdr = " ro_cnt ro_bytes % | rw_cnt rw_bytes % | all_cnt all_bytes %";
965
966 LogMessage(cds) msg;
967
968 msg.info("Detailed metadata info (excluding od/st regions; rw stats include md/mc regions):");
969 msg.info("%s", hdr);
970 msg.info("%s", sep);
971 for (int type = 0; type < int(_number_of_types); type ++) {
972 const char *name = type_name((Type)type);
973 int ro_count = _counts[RO][type];
974 int ro_bytes = _bytes [RO][type];
975 int rw_count = _counts[RW][type];
976 int rw_bytes = _bytes [RW][type];
977 int count = ro_count + rw_count;
978 int bytes = ro_bytes + rw_bytes;
979
980 double ro_perc = percent_of(ro_bytes, ro_all);
981 double rw_perc = percent_of(rw_bytes, rw_all);
982 double perc = percent_of(bytes, ro_all + rw_all);
983
984 msg.info(fmt_stats, name,
985 ro_count, ro_bytes, ro_perc,
986 rw_count, rw_bytes, rw_perc,
987 count, bytes, perc);
988
989 all_ro_count += ro_count;
990 all_ro_bytes += ro_bytes;
991 all_rw_count += rw_count;
992 all_rw_bytes += rw_bytes;
993 }
994
995 int all_count = all_ro_count + all_rw_count;
996 int all_bytes = all_ro_bytes + all_rw_bytes;
997
998 double all_ro_perc = percent_of(all_ro_bytes, ro_all);
999 double all_rw_perc = percent_of(all_rw_bytes, rw_all);
1000 double all_perc = percent_of(all_bytes, ro_all + rw_all);
1001
1002 msg.info("%s", sep);
1003 msg.info(fmt_stats, "Total",
1004 all_ro_count, all_ro_bytes, all_ro_perc,
1005 all_rw_count, all_rw_bytes, all_rw_perc,
1006 all_count, all_bytes, all_perc);
1007
1008 assert(all_ro_bytes == ro_all, "everything should have been counted");
1009 assert(all_rw_bytes == rw_all, "everything should have been counted");
1010
1011 #undef fmt_stats
1012 }
1013
1014 // Populate the shared space.
1015
1016 class VM_PopulateDumpSharedSpace: public VM_Operation {
1017 private:
1018 GrowableArray<MemRegion> *_closed_archive_heap_regions;
1019 GrowableArray<MemRegion> *_open_archive_heap_regions;
1020
1021 void dump_java_heap_objects() NOT_CDS_JAVA_HEAP_RETURN;
1022 void dump_symbols();
1023 char* dump_read_only_tables();
1024 void print_region_stats();
1025 void print_heap_region_stats(GrowableArray<MemRegion> *heap_mem,
1026 const char *name, const size_t total_size);
1027 public:
1028
1029 VMOp_Type type() const { return VMOp_PopulateDumpSharedSpace; }
1030 void doit(); // outline because gdb sucks
1031 static void write_region(FileMapInfo* mapinfo, int region, DumpRegion* space, bool read_only, bool allow_exec);
1032 bool allow_nested_vm_operations() const { return true; }
1033 }; // class VM_PopulateDumpSharedSpace
1034
1035 class SortedSymbolClosure: public SymbolClosure {
1036 GrowableArray<Symbol*> _symbols;
1037 virtual void do_symbol(Symbol** sym) {
1038 assert((*sym)->is_permanent(), "archived symbols must be permanent");
1039 _symbols.append(*sym);
1040 }
1041 static int compare_symbols_by_address(Symbol** a, Symbol** b) {
1042 if (a[0] < b[0]) {
1043 return -1;
1044 } else if (a[0] == b[0]) {
1045 return 0;
1046 } else {
1047 return 1;
1048 }
1049 }
1050
1051 public:
1052 SortedSymbolClosure() {
1053 SymbolTable::symbols_do(this);
1054 _symbols.sort(compare_symbols_by_address);
1055 }
1056 GrowableArray<Symbol*>* get_sorted_symbols() {
1057 return &_symbols;
1058 }
1059 };
1060
1061 // ArchiveCompactor --
1062 //
1063 // This class is the central piece of shared archive compaction -- all metaspace data are
1064 // initially allocated outside of the shared regions. ArchiveCompactor copies the
1065 // metaspace data into their final location in the shared regions.
1066
1067 class ArchiveCompactor : AllStatic {
1068 static DumpAllocStats* _alloc_stats;
1069 static SortedSymbolClosure* _ssc;
1070
1071 static unsigned my_hash(const address& a) {
1072 return primitive_hash<address>(a);
1073 }
1074 static bool my_equals(const address& a0, const address& a1) {
1075 return primitive_equals<address>(a0, a1);
1076 }
1077 typedef ResourceHashtable<
1078 address, address,
1079 ArchiveCompactor::my_hash, // solaris compiler doesn't like: primitive_hash<address>
1080 ArchiveCompactor::my_equals, // solaris compiler doesn't like: primitive_equals<address>
1081 16384, ResourceObj::C_HEAP> RelocationTable;
1082 static RelocationTable* _new_loc_table;
1083
1084 public:
1085 static void initialize() {
1086 _alloc_stats = new(ResourceObj::C_HEAP, mtInternal)DumpAllocStats;
1087 _new_loc_table = new(ResourceObj::C_HEAP, mtInternal)RelocationTable;
1088 }
1089 static DumpAllocStats* alloc_stats() {
1090 return _alloc_stats;
1091 }
1092
1093 static void allocate(MetaspaceClosure::Ref* ref, bool read_only) {
1094 address obj = ref->obj();
1095 int bytes = ref->size() * BytesPerWord;
1096 char* p;
1097 size_t alignment = BytesPerWord;
1098 char* oldtop;
1099 char* newtop;
1100
1101 if (read_only) {
1102 oldtop = _ro_region.top();
1103 p = _ro_region.allocate(bytes, alignment);
1104 newtop = _ro_region.top();
1105 } else {
1106 oldtop = _rw_region.top();
1107 p = _rw_region.allocate(bytes, alignment);
1108 newtop = _rw_region.top();
1109 }
1110 memcpy(p, obj, bytes);
1111 bool isnew = _new_loc_table->put(obj, (address)p);
1112 log_trace(cds)("Copy: " PTR_FORMAT " ==> " PTR_FORMAT " %d", p2i(obj), p2i(p), bytes);
1113 assert(isnew, "must be");
1114
1115 _alloc_stats->record(ref->msotype(), int(newtop - oldtop), read_only);
1116 if (ref->msotype() == MetaspaceObj::SymbolType) {
1117 uintx delta = MetaspaceShared::object_delta(p);
1118 if (delta > MAX_SHARED_DELTA) {
1119 // This is just a sanity check and should not appear in any real world usage. This
1120 // happens only if you allocate more than 2GB of Symbols and would require
1121 // millions of shared classes.
1122 vm_exit_during_initialization("Too many Symbols in the CDS archive",
1123 "Please reduce the number of shared classes.");
1124 }
1125 }
1126 }
1127
1128 static address get_new_loc(MetaspaceClosure::Ref* ref) {
1129 address* pp = _new_loc_table->get(ref->obj());
1130 assert(pp != NULL, "must be");
1131 return *pp;
1132 }
1133
1134 private:
1135 // Makes a shallow copy of visited MetaspaceObj's
1136 class ShallowCopier: public UniqueMetaspaceClosure {
1137 bool _read_only;
1138 public:
1139 ShallowCopier(bool read_only) : _read_only(read_only) {}
1140
1141 virtual void do_unique_ref(Ref* ref, bool read_only) {
1142 if (read_only == _read_only) {
1143 allocate(ref, read_only);
1144 }
1145 }
1146 };
1147
1148 // Relocate embedded pointers within a MetaspaceObj's shallow copy
1149 class ShallowCopyEmbeddedRefRelocator: public UniqueMetaspaceClosure {
1150 public:
1151 virtual void do_unique_ref(Ref* ref, bool read_only) {
1152 address new_loc = get_new_loc(ref);
1153 RefRelocator refer;
1154 ref->metaspace_pointers_do_at(&refer, new_loc);
1155 }
1156 };
1157
1158 // Relocate a reference to point to its shallow copy
1159 class RefRelocator: public MetaspaceClosure {
1160 public:
1161 virtual bool do_ref(Ref* ref, bool read_only) {
1162 if (ref->not_null()) {
1163 ref->update(get_new_loc(ref));
1164 }
1165 return false; // Do not recurse.
1166 }
1167 };
1168
1169 #ifdef ASSERT
1170 class IsRefInArchiveChecker: public MetaspaceClosure {
1171 public:
1172 virtual bool do_ref(Ref* ref, bool read_only) {
1173 if (ref->not_null()) {
1174 char* obj = (char*)ref->obj();
1175 assert(_ro_region.contains(obj) || _rw_region.contains(obj),
1176 "must be relocated to point to CDS archive");
1177 }
1178 return false; // Do not recurse.
1179 }
1180 };
1181 #endif
1182
1183 public:
1184 static void copy_and_compact() {
1185 // We should no longer allocate anything from the metaspace, so that
1186 // we can have a stable set of MetaspaceObjs to work with.
1187 Metaspace::freeze();
1188
1189 ResourceMark rm;
1190 SortedSymbolClosure the_ssc; // StackObj
1191 _ssc = &the_ssc;
1192
1193 tty->print_cr("Scanning all metaspace objects ... ");
1194 {
1195 // allocate and shallow-copy RW objects, immediately following the MC region
1196 tty->print_cr("Allocating RW objects ... ");
1197 _mc_region.pack(&_rw_region);
1198
1199 ResourceMark rm;
1200 ShallowCopier rw_copier(false);
1201 iterate_roots(&rw_copier);
1202 }
1203 {
1204 // allocate and shallow-copy of RO object, immediately following the RW region
1205 tty->print_cr("Allocating RO objects ... ");
1206 _rw_region.pack(&_ro_region);
1207
1208 ResourceMark rm;
1209 ShallowCopier ro_copier(true);
1210 iterate_roots(&ro_copier);
1211 }
1212 {
1213 tty->print_cr("Relocating embedded pointers ... ");
1214 ResourceMark rm;
1215 ShallowCopyEmbeddedRefRelocator emb_reloc;
1216 iterate_roots(&emb_reloc);
1217 }
1218 {
1219 tty->print_cr("Relocating external roots ... ");
1220 ResourceMark rm;
1221 RefRelocator ext_reloc;
1222 iterate_roots(&ext_reloc);
1223 }
1224
1225 #ifdef ASSERT
1226 {
1227 tty->print_cr("Verifying external roots ... ");
1228 ResourceMark rm;
1229 IsRefInArchiveChecker checker;
1230 iterate_roots(&checker);
1231 }
1232 #endif
1233
1234
1235 // cleanup
1236 _ssc = NULL;
1237 }
1238
1239 // We must relocate the System::_well_known_klasses only after we have copied the
1240 // java objects in during dump_java_heap_objects(): during the object copy, we operate on
1241 // old objects which assert that their klass is the original klass.
1242 static void relocate_well_known_klasses() {
1243 {
1244 tty->print_cr("Relocating SystemDictionary::_well_known_klasses[] ... ");
1245 ResourceMark rm;
1246 RefRelocator ext_reloc;
1247 SystemDictionary::well_known_klasses_do(&ext_reloc);
1248 }
1249 // NOTE: after this point, we shouldn't have any globals that can reach the old
1250 // objects.
1251
1252 // We cannot use any of the objects in the heap anymore (except for the objects
1253 // in the CDS shared string regions) because their headers no longer point to
1254 // valid Klasses.
1255 }
1256
1257 static void iterate_roots(MetaspaceClosure* it) {
1258 GrowableArray<Symbol*>* symbols = _ssc->get_sorted_symbols();
1259 for (int i=0; i<symbols->length(); i++) {
1260 it->push(symbols->adr_at(i));
1261 }
1262 if (_global_klass_objects != NULL) {
1263 // Need to fix up the pointers
1264 for (int i = 0; i < _global_klass_objects->length(); i++) {
1265 // NOTE -- this requires that the vtable is NOT yet patched, or else we are hosed.
1266 it->push(_global_klass_objects->adr_at(i));
1267 }
1268 }
1269 FileMapInfo::metaspace_pointers_do(it);
1270 SystemDictionary::classes_do(it);
1271 Universe::metaspace_pointers_do(it);
1272 SymbolTable::metaspace_pointers_do(it);
1273 vmSymbols::metaspace_pointers_do(it);
1274 }
1275
1276 static Klass* get_relocated_klass(Klass* orig_klass) {
1277 assert(DumpSharedSpaces, "dump time only");
1278 address* pp = _new_loc_table->get((address)orig_klass);
1279 assert(pp != NULL, "must be");
1280 Klass* klass = (Klass*)(*pp);
1281 assert(klass->is_klass(), "must be");
1282 return klass;
1283 }
1284 };
1285
1286 DumpAllocStats* ArchiveCompactor::_alloc_stats;
1287 SortedSymbolClosure* ArchiveCompactor::_ssc;
1288 ArchiveCompactor::RelocationTable* ArchiveCompactor::_new_loc_table;
1289
1290 void VM_PopulateDumpSharedSpace::write_region(FileMapInfo* mapinfo, int region_idx,
1291 DumpRegion* dump_region, bool read_only, bool allow_exec) {
1292 mapinfo->write_region(region_idx, dump_region->base(), dump_region->used(), read_only, allow_exec);
1293 }
1294
1295 void VM_PopulateDumpSharedSpace::dump_symbols() {
1296 tty->print_cr("Dumping symbol table ...");
1297
1298 NOT_PRODUCT(SymbolTable::verify());
1299 SymbolTable::write_to_archive();
1300 }
1301
1302 char* VM_PopulateDumpSharedSpace::dump_read_only_tables() {
1303 char* oldtop = _ro_region.top();
1304 // Reorder the system dictionary. Moving the symbols affects
1305 // how the hash table indices are calculated.
1306 SystemDictionary::reorder_dictionary_for_sharing();
1307
1308 tty->print("Removing java_mirror ... ");
1309 if (!MetaspaceShared::is_heap_object_archiving_allowed()) {
1310 clear_basic_type_mirrors();
1311 }
1312 remove_java_mirror_in_classes();
1313 tty->print_cr("done. ");
1314 NOT_PRODUCT(SystemDictionary::verify();)
1315
1316 size_t buckets_bytes = SystemDictionary::count_bytes_for_buckets();
1317 char* buckets_top = _ro_region.allocate(buckets_bytes, sizeof(intptr_t));
1318 SystemDictionary::copy_buckets(buckets_top, _ro_region.top());
1319
1320 size_t table_bytes = SystemDictionary::count_bytes_for_table();
1321 char* table_top = _ro_region.allocate(table_bytes, sizeof(intptr_t));
1322 SystemDictionary::copy_table(table_top, _ro_region.top());
1323
1324 // Write the archived object sub-graph infos. For each klass with sub-graphs,
1325 // the info includes the static fields (sub-graph entry points) and Klasses
1326 // of objects included in the sub-graph.
1327 HeapShared::write_archived_subgraph_infos();
1328
1329 // Write the other data to the output array.
1330 WriteClosure wc(&_ro_region);
1331 MetaspaceShared::serialize(&wc);
1332
1333 char* newtop = _ro_region.top();
1334 ArchiveCompactor::alloc_stats()->record_other_type(int(newtop - oldtop), true);
1335 return buckets_top;
1336 }
1337
1338 void VM_PopulateDumpSharedSpace::doit() {
1339 Thread* THREAD = VMThread::vm_thread();
1340
1341 FileMapInfo::check_nonempty_dir_in_shared_path_table();
1342
1343 NOT_PRODUCT(SystemDictionary::verify();)
1344 // The following guarantee is meant to ensure that no loader constraints
1345 // exist yet, since the constraints table is not shared. This becomes
1346 // more important now that we don't re-initialize vtables/itables for
1347 // shared classes at runtime, where constraints were previously created.
1348 guarantee(SystemDictionary::constraints()->number_of_entries() == 0,
1349 "loader constraints are not saved");
1350 guarantee(SystemDictionary::placeholders()->number_of_entries() == 0,
1351 "placeholders are not saved");
1352 // Revisit and implement this if we prelink method handle call sites:
1353 guarantee(SystemDictionary::invoke_method_table() == NULL ||
1354 SystemDictionary::invoke_method_table()->number_of_entries() == 0,
1355 "invoke method table is not saved");
1356
1357 // At this point, many classes have been loaded.
1358 // Gather systemDictionary classes in a global array and do everything to
1359 // that so we don't have to walk the SystemDictionary again.
1360 _global_klass_objects = new GrowableArray<Klass*>(1000);
1361 CollectClassesClosure collect_classes;
1362 ClassLoaderDataGraph::loaded_classes_do(&collect_classes);
1363
1364 tty->print_cr("Number of classes %d", _global_klass_objects->length());
1365 {
1366 int num_type_array = 0, num_obj_array = 0, num_inst = 0;
1367 for (int i = 0; i < _global_klass_objects->length(); i++) {
1368 Klass* k = _global_klass_objects->at(i);
1369 if (k->is_instance_klass()) {
1370 num_inst ++;
1371 } else if (k->is_objArray_klass()) {
1372 num_obj_array ++;
1373 } else {
1374 assert(k->is_typeArray_klass(), "sanity");
1375 num_type_array ++;
1376 }
1377 }
1378 tty->print_cr(" instance classes = %5d", num_inst);
1379 tty->print_cr(" obj array classes = %5d", num_obj_array);
1380 tty->print_cr(" type array classes = %5d", num_type_array);
1381 }
1382
1383 // Ensure the ConstMethods won't be modified at run-time
1384 tty->print("Updating ConstMethods ... ");
1385 rewrite_nofast_bytecodes_and_calculate_fingerprints();
1386 tty->print_cr("done. ");
1387
1388 // Move classes from platform/system dictionaries into the boot dictionary
1389 SystemDictionary::combine_shared_dictionaries();
1390
1391 // Make sure all classes have a correct loader type.
1392 ClassLoaderData::the_null_class_loader_data()->dictionary()->classes_do(MetaspaceShared::check_shared_class_loader_type);
1393
1394 // Remove all references outside the metadata
1395 tty->print("Removing unshareable information ... ");
1396 remove_unshareable_in_classes();
1397 tty->print_cr("done. ");
1398
1399 // We don't support archiving anonymous classes. Verify that they are not stored in
1400 // the any dictionaries.
1401 NOT_PRODUCT(assert_no_anonymoys_classes_in_dictionaries());
1402
1403 SystemDictionaryShared::finalize_verification_constraints();
1404
1405 ArchiveCompactor::initialize();
1406 ArchiveCompactor::copy_and_compact();
1407
1408 dump_symbols();
1409
1410 // Dump supported java heap objects
1411 _closed_archive_heap_regions = NULL;
1412 _open_archive_heap_regions = NULL;
1413 dump_java_heap_objects();
1414
1415 ArchiveCompactor::relocate_well_known_klasses();
1416
1417 char* read_only_tables_start = dump_read_only_tables();
1418 _ro_region.pack(&_md_region);
1419
1420 char* vtbl_list = _md_region.top();
1421 MetaspaceShared::allocate_cpp_vtable_clones();
1422 _md_region.pack(&_od_region);
1423
1424 // Relocate the archived class file data into the od region
1425 relocate_cached_class_file();
1426 _od_region.pack();
1427
1428 // The 5 core spaces are allocated consecutively mc->rw->ro->md->od, so there total size
1429 // is just the spaces between the two ends.
1430 size_t core_spaces_size = _od_region.end() - _mc_region.base();
1431 assert(core_spaces_size == (size_t)align_up(core_spaces_size, Metaspace::reserve_alignment()),
1432 "should already be aligned");
1433
1434 // During patching, some virtual methods may be called, so at this point
1435 // the vtables must contain valid methods (as filled in by CppVtableCloner::allocate).
1436 MetaspaceShared::patch_cpp_vtable_pointers();
1437
1438 // The vtable clones contain addresses of the current process.
1439 // We don't want to write these addresses into the archive.
1440 MetaspaceShared::zero_cpp_vtable_clones_for_writing();
1441
1442 // Create and write the archive file that maps the shared spaces.
1443
1444 FileMapInfo* mapinfo = new FileMapInfo();
1445 mapinfo->populate_header(os::vm_allocation_granularity());
1446 mapinfo->set_read_only_tables_start(read_only_tables_start);
1447 mapinfo->set_misc_data_patching_start(vtbl_list);
1448 mapinfo->set_cds_i2i_entry_code_buffers(MetaspaceShared::cds_i2i_entry_code_buffers());
1449 mapinfo->set_cds_i2i_entry_code_buffers_size(MetaspaceShared::cds_i2i_entry_code_buffers_size());
1450 mapinfo->set_core_spaces_size(core_spaces_size);
1451
1452 for (int pass=1; pass<=2; pass++) {
1453 if (pass == 1) {
1454 // The first pass doesn't actually write the data to disk. All it
1455 // does is to update the fields in the mapinfo->_header.
1456 } else {
1457 // After the first pass, the contents of mapinfo->_header are finalized,
1458 // so we can compute the header's CRC, and write the contents of the header
1459 // and the regions into disk.
1460 mapinfo->open_for_write();
1461 mapinfo->set_header_crc(mapinfo->compute_header_crc());
1462 }
1463 mapinfo->write_header();
1464
1465 // NOTE: md contains the trampoline code for method entries, which are patched at run time,
1466 // so it needs to be read/write.
1467 write_region(mapinfo, MetaspaceShared::mc, &_mc_region, /*read_only=*/false,/*allow_exec=*/true);
1468 write_region(mapinfo, MetaspaceShared::rw, &_rw_region, /*read_only=*/false,/*allow_exec=*/false);
1469 write_region(mapinfo, MetaspaceShared::ro, &_ro_region, /*read_only=*/true, /*allow_exec=*/false);
1470 write_region(mapinfo, MetaspaceShared::md, &_md_region, /*read_only=*/false,/*allow_exec=*/false);
1471 write_region(mapinfo, MetaspaceShared::od, &_od_region, /*read_only=*/true, /*allow_exec=*/false);
1472
1473 _total_string_region_size = mapinfo->write_archive_heap_regions(
1474 _closed_archive_heap_regions,
1475 MetaspaceShared::first_string,
1476 MetaspaceShared::max_strings);
1477 _total_open_archive_region_size = mapinfo->write_archive_heap_regions(
1478 _open_archive_heap_regions,
1479 MetaspaceShared::first_open_archive_heap_region,
1480 MetaspaceShared::max_open_archive_heap_region);
1481 }
1482
1483 mapinfo->close();
1484
1485 // Restore the vtable in case we invoke any virtual methods.
1486 MetaspaceShared::clone_cpp_vtables((intptr_t*)vtbl_list);
1487
1488 print_region_stats();
1489
1490 if (log_is_enabled(Info, cds)) {
1491 ArchiveCompactor::alloc_stats()->print_stats(int(_ro_region.used()), int(_rw_region.used()),
1492 int(_mc_region.used()), int(_md_region.used()));
1493 }
1494
1495 if (PrintSystemDictionaryAtExit) {
1496 SystemDictionary::print();
1497 }
1498 // There may be other pending VM operations that operate on the InstanceKlasses,
1499 // which will fail because InstanceKlasses::remove_unshareable_info()
1500 // has been called. Forget these operations and exit the VM directly.
1501 vm_direct_exit(0);
1502 }
1503
1504 void VM_PopulateDumpSharedSpace::print_region_stats() {
1505 // Print statistics of all the regions
1506 const size_t total_reserved = _ro_region.reserved() + _rw_region.reserved() +
1507 _mc_region.reserved() + _md_region.reserved() +
1508 _od_region.reserved() +
1509 _total_string_region_size +
1510 _total_open_archive_region_size;
1511 const size_t total_bytes = _ro_region.used() + _rw_region.used() +
1512 _mc_region.used() + _md_region.used() +
1513 _od_region.used() +
1514 _total_string_region_size +
1515 _total_open_archive_region_size;
1516 const double total_u_perc = percent_of(total_bytes, total_reserved);
1517
1518 _mc_region.print(total_reserved);
1519 _rw_region.print(total_reserved);
1520 _ro_region.print(total_reserved);
1521 _md_region.print(total_reserved);
1522 _od_region.print(total_reserved);
1523 print_heap_region_stats(_closed_archive_heap_regions, "st", total_reserved);
1524 print_heap_region_stats(_open_archive_heap_regions, "oa", total_reserved);
1525
1526 tty->print_cr("total : " SIZE_FORMAT_W(9) " [100.0%% of total] out of " SIZE_FORMAT_W(9) " bytes [%5.1f%% used]",
1527 total_bytes, total_reserved, total_u_perc);
1528 }
1529
1530 void VM_PopulateDumpSharedSpace::print_heap_region_stats(GrowableArray<MemRegion> *heap_mem,
1531 const char *name, const size_t total_size) {
1532 int arr_len = heap_mem == NULL ? 0 : heap_mem->length();
1533 for (int i = 0; i < arr_len; i++) {
1534 char* start = (char*)heap_mem->at(i).start();
1535 size_t size = heap_mem->at(i).byte_size();
1536 char* top = start + size;
1537 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,
1538 name, i, size, size/double(total_size)*100.0, size, p2i(start));
1539
1540 }
1541 }
1542
1543 // Update a Java object to point its Klass* to the new location after
1544 // shared archive has been compacted.
1545 void MetaspaceShared::relocate_klass_ptr(oop o) {
1546 assert(DumpSharedSpaces, "sanity");
1547 Klass* k = ArchiveCompactor::get_relocated_klass(o->klass());
1548 o->set_klass(k);
1549 }
1550
1551 Klass* MetaspaceShared::get_relocated_klass(Klass *k) {
1552 assert(DumpSharedSpaces, "sanity");
1553 return ArchiveCompactor::get_relocated_klass(k);
1554 }
1555
1556 class LinkSharedClassesClosure : public KlassClosure {
1557 Thread* THREAD;
1558 bool _made_progress;
1559 public:
1560 LinkSharedClassesClosure(Thread* thread) : THREAD(thread), _made_progress(false) {}
1561
1562 void reset() { _made_progress = false; }
1563 bool made_progress() const { return _made_progress; }
1564
1565 void do_klass(Klass* k) {
1566 if (k->is_instance_klass()) {
1567 InstanceKlass* ik = InstanceKlass::cast(k);
1568 // Link the class to cause the bytecodes to be rewritten and the
1569 // cpcache to be created. Class verification is done according
1570 // to -Xverify setting.
1571 _made_progress |= MetaspaceShared::try_link_class(ik, THREAD);
1572 guarantee(!HAS_PENDING_EXCEPTION, "exception in link_class");
1573
1574 ik->constants()->resolve_class_constants(THREAD);
1575 }
1576 }
1577 };
1578
1579 class CheckSharedClassesClosure : public KlassClosure {
1580 bool _made_progress;
1581 public:
1582 CheckSharedClassesClosure() : _made_progress(false) {}
1583
1584 void reset() { _made_progress = false; }
1585 bool made_progress() const { return _made_progress; }
1586 void do_klass(Klass* k) {
1587 if (k->is_instance_klass() && InstanceKlass::cast(k)->check_sharing_error_state()) {
1588 _made_progress = true;
1589 }
1590 }
1591 };
1592
1593 void MetaspaceShared::check_shared_class_loader_type(InstanceKlass* ik) {
1594 ResourceMark rm;
1595 if (ik->shared_classpath_index() == UNREGISTERED_INDEX) {
1596 guarantee(ik->loader_type() == 0,
1597 "Class loader type must not be set for this class %s", ik->name()->as_C_string());
1598 } else {
1599 guarantee(ik->loader_type() != 0,
1600 "Class loader type must be set for this class %s", ik->name()->as_C_string());
1601 }
1602 }
1603
1604 void MetaspaceShared::link_and_cleanup_shared_classes(TRAPS) {
1605 // We need to iterate because verification may cause additional classes
1606 // to be loaded.
1607 LinkSharedClassesClosure link_closure(THREAD);
1608 do {
1609 link_closure.reset();
1610 ClassLoaderDataGraph::loaded_classes_do(&link_closure);
1611 guarantee(!HAS_PENDING_EXCEPTION, "exception in link_class");
1612 } while (link_closure.made_progress());
1613
1614 if (_has_error_classes) {
1615 // Mark all classes whose super class or interfaces failed verification.
1616 CheckSharedClassesClosure check_closure;
1617 do {
1618 // Not completely sure if we need to do this iteratively. Anyway,
1619 // we should come here only if there are unverifiable classes, which
1620 // shouldn't happen in normal cases. So better safe than sorry.
1621 check_closure.reset();
1622 ClassLoaderDataGraph::loaded_classes_do(&check_closure);
1623 } while (check_closure.made_progress());
1624
1625 if (IgnoreUnverifiableClassesDuringDump) {
1626 // This is useful when running JCK or SQE tests. You should not
1627 // enable this when running real apps.
1628 SystemDictionary::remove_classes_in_error_state();
1629 } else {
1630 tty->print_cr("Please remove the unverifiable classes from your class list and try again");
1631 exit(1);
1632 }
1633 }
1634 }
1635
1636 void MetaspaceShared::prepare_for_dumping() {
1637 Arguments::check_unsupported_dumping_properties();
1638 ClassLoader::initialize_shared_path();
1639 }
1640
1641 // Preload classes from a list, populate the shared spaces and dump to a
1642 // file.
1643 void MetaspaceShared::preload_and_dump(TRAPS) {
1644 { TraceTime timer("Dump Shared Spaces", TRACETIME_LOG(Info, startuptime));
1645 ResourceMark rm;
1646 char class_list_path_str[JVM_MAXPATHLEN];
1647 // Preload classes to be shared.
1648 // Should use some os:: method rather than fopen() here. aB.
1649 const char* class_list_path;
1650 if (SharedClassListFile == NULL) {
1651 // Construct the path to the class list (in jre/lib)
1652 // Walk up two directories from the location of the VM and
1653 // optionally tack on "lib" (depending on platform)
1654 os::jvm_path(class_list_path_str, sizeof(class_list_path_str));
1655 for (int i = 0; i < 3; i++) {
1656 char *end = strrchr(class_list_path_str, *os::file_separator());
1657 if (end != NULL) *end = '\0';
1658 }
1659 int class_list_path_len = (int)strlen(class_list_path_str);
1660 if (class_list_path_len >= 3) {
1661 if (strcmp(class_list_path_str + class_list_path_len - 3, "lib") != 0) {
1662 if (class_list_path_len < JVM_MAXPATHLEN - 4) {
1663 jio_snprintf(class_list_path_str + class_list_path_len,
1664 sizeof(class_list_path_str) - class_list_path_len,
1665 "%slib", os::file_separator());
1666 class_list_path_len += 4;
1667 }
1668 }
1669 }
1670 if (class_list_path_len < JVM_MAXPATHLEN - 10) {
1671 jio_snprintf(class_list_path_str + class_list_path_len,
1672 sizeof(class_list_path_str) - class_list_path_len,
1673 "%sclasslist", os::file_separator());
1674 }
1675 class_list_path = class_list_path_str;
1676 } else {
1677 class_list_path = SharedClassListFile;
1678 }
1679
1680 tty->print_cr("Loading classes to share ...");
1681 _has_error_classes = false;
1682 int class_count = preload_classes(class_list_path, THREAD);
1683 if (ExtraSharedClassListFile) {
1684 class_count += preload_classes(ExtraSharedClassListFile, THREAD);
1685 }
1686 tty->print_cr("Loading classes to share: done.");
1687
1688 log_info(cds)("Shared spaces: preloaded %d classes", class_count);
1689
1690 // Rewrite and link classes
1691 tty->print_cr("Rewriting and linking classes ...");
1692
1693 // Link any classes which got missed. This would happen if we have loaded classes that
1694 // were not explicitly specified in the classlist. E.g., if an interface implemented by class K
1695 // fails verification, all other interfaces that were not specified in the classlist but
1696 // are implemented by K are not verified.
1697 link_and_cleanup_shared_classes(CATCH);
1698 tty->print_cr("Rewriting and linking classes: done");
1699
1700 SystemDictionary::clear_invoke_method_table();
1701 HeapShared::init_archivable_static_fields(THREAD);
1702
1703 VM_PopulateDumpSharedSpace op;
1704 VMThread::execute(&op);
1705 }
1706 }
1707
1708
1709 int MetaspaceShared::preload_classes(const char* class_list_path, TRAPS) {
1710 ClassListParser parser(class_list_path);
1711 int class_count = 0;
1712
1713 while (parser.parse_one_line()) {
1714 Klass* klass = ClassLoaderExt::load_one_class(&parser, THREAD);
1715 if (HAS_PENDING_EXCEPTION) {
1716 if (klass == NULL &&
1717 (PENDING_EXCEPTION->klass()->name() == vmSymbols::java_lang_ClassNotFoundException())) {
1718 // print a warning only when the pending exception is class not found
1719 tty->print_cr("Preload Warning: Cannot find %s", parser.current_class_name());
1720 }
1721 CLEAR_PENDING_EXCEPTION;
1722 }
1723 if (klass != NULL) {
1724 if (log_is_enabled(Trace, cds)) {
1725 ResourceMark rm;
1726 log_trace(cds)("Shared spaces preloaded: %s", klass->external_name());
1727 }
1728
1729 if (klass->is_instance_klass()) {
1730 InstanceKlass* ik = InstanceKlass::cast(klass);
1731
1732 // Link the class to cause the bytecodes to be rewritten and the
1733 // cpcache to be created. The linking is done as soon as classes
1734 // are loaded in order that the related data structures (klass and
1735 // cpCache) are located together.
1736 try_link_class(ik, THREAD);
1737 guarantee(!HAS_PENDING_EXCEPTION, "exception in link_class");
1738 }
1739
1740 class_count++;
1741 }
1742 }
1743
1744 return class_count;
1745 }
1746
1747 // Returns true if the class's status has changed
1748 bool MetaspaceShared::try_link_class(InstanceKlass* ik, TRAPS) {
1749 assert(DumpSharedSpaces, "should only be called during dumping");
1750 if (ik->init_state() < InstanceKlass::linked) {
1751 bool saved = BytecodeVerificationLocal;
1752 if (ik->loader_type() == 0 && ik->class_loader() == NULL) {
1753 // The verification decision is based on BytecodeVerificationRemote
1754 // for non-system classes. Since we are using the NULL classloader
1755 // to load non-system classes for customized class loaders during dumping,
1756 // we need to temporarily change BytecodeVerificationLocal to be the same as
1757 // BytecodeVerificationRemote. Note this can cause the parent system
1758 // classes also being verified. The extra overhead is acceptable during
1759 // dumping.
1760 BytecodeVerificationLocal = BytecodeVerificationRemote;
1761 }
1762 ik->link_class(THREAD);
1763 if (HAS_PENDING_EXCEPTION) {
1764 ResourceMark rm;
1765 tty->print_cr("Preload Warning: Verification failed for %s",
1766 ik->external_name());
1767 CLEAR_PENDING_EXCEPTION;
1768 ik->set_in_error_state();
1769 _has_error_classes = true;
1770 }
1771 BytecodeVerificationLocal = saved;
1772 return true;
1773 } else {
1774 return false;
1775 }
1776 }
1777
1778 #if INCLUDE_CDS_JAVA_HEAP
1779 void VM_PopulateDumpSharedSpace::dump_java_heap_objects() {
1780 if (!MetaspaceShared::is_heap_object_archiving_allowed()) {
1781 if (log_is_enabled(Info, cds)) {
1782 log_info(cds)(
1783 "Archived java heap is not supported as UseG1GC, "
1784 "UseCompressedOops and UseCompressedClassPointers are required."
1785 "Current settings: UseG1GC=%s, UseCompressedOops=%s, UseCompressedClassPointers=%s.",
1786 BOOL_TO_STR(UseG1GC), BOOL_TO_STR(UseCompressedOops),
1787 BOOL_TO_STR(UseCompressedClassPointers));
1788 }
1789 return;
1790 }
1791
1792 {
1793 NoSafepointVerifier nsv;
1794
1795 // Cache for recording where the archived objects are copied to
1796 MetaspaceShared::create_archive_object_cache();
1797
1798 tty->print_cr("Dumping objects to closed archive heap region ...");
1799 NOT_PRODUCT(StringTable::verify());
1800 // The closed space has maximum two regions. See FileMapInfo::write_archive_heap_regions() for details.
1801 _closed_archive_heap_regions = new GrowableArray<MemRegion>(2);
1802 MetaspaceShared::dump_closed_archive_heap_objects(_closed_archive_heap_regions);
1803
1804 tty->print_cr("Dumping objects to open archive heap region ...");
1805 _open_archive_heap_regions = new GrowableArray<MemRegion>(2);
1806 MetaspaceShared::dump_open_archive_heap_objects(_open_archive_heap_regions);
1807
1808 MetaspaceShared::destroy_archive_object_cache();
1809 }
1810
1811 G1HeapVerifier::verify_archive_regions();
1812 }
1813
1814 void MetaspaceShared::dump_closed_archive_heap_objects(
1815 GrowableArray<MemRegion> * closed_archive) {
1816 assert(is_heap_object_archiving_allowed(), "Cannot dump java heap objects");
1817
1818 Thread* THREAD = Thread::current();
1819 G1CollectedHeap::heap()->begin_archive_alloc_range();
1820
1821 // Archive interned string objects
1822 StringTable::write_to_archive();
1823
1824 G1CollectedHeap::heap()->end_archive_alloc_range(closed_archive,
1825 os::vm_allocation_granularity());
1826 }
1827
1828 void MetaspaceShared::dump_open_archive_heap_objects(
1829 GrowableArray<MemRegion> * open_archive) {
1830 assert(UseG1GC, "Only support G1 GC");
1831 assert(UseCompressedOops && UseCompressedClassPointers,
1832 "Only support UseCompressedOops and UseCompressedClassPointers enabled");
1833
1834 Thread* THREAD = Thread::current();
1835 G1CollectedHeap::heap()->begin_archive_alloc_range(true /* open */);
1836
1837 java_lang_Class::archive_basic_type_mirrors(THREAD);
1838
1839 MetaspaceShared::archive_klass_objects(THREAD);
1840
1841 HeapShared::archive_module_graph_objects(THREAD);
1842
1843 G1CollectedHeap::heap()->end_archive_alloc_range(open_archive,
1844 os::vm_allocation_granularity());
1845 }
1846
1847 unsigned MetaspaceShared::obj_hash(oop const& p) {
1848 assert(!p->mark()->has_bias_pattern(),
1849 "this object should never have been locked"); // so identity_hash won't safepoin
1850 unsigned hash = (unsigned)p->identity_hash();
1851 return hash;
1852 }
1853
1854 MetaspaceShared::ArchivedObjectCache* MetaspaceShared::_archive_object_cache = NULL;
1855 oop MetaspaceShared::find_archived_heap_object(oop obj) {
1856 assert(DumpSharedSpaces, "dump-time only");
1857 ArchivedObjectCache* cache = MetaspaceShared::archive_object_cache();
1858 oop* p = cache->get(obj);
1859 if (p != NULL) {
1860 return *p;
1861 } else {
1862 return NULL;
1863 }
1864 }
1865
1866 oop MetaspaceShared::archive_heap_object(oop obj, Thread* THREAD) {
1867 assert(DumpSharedSpaces, "dump-time only");
1868
1869 oop ao = find_archived_heap_object(obj);
1870 if (ao != NULL) {
1871 // already archived
1872 return ao;
1873 }
1874
1875 int len = obj->size();
1876 if (G1CollectedHeap::heap()->is_archive_alloc_too_large(len)) {
1877 log_debug(cds, heap)("Cannot archive, object (" PTR_FORMAT ") is too large: " SIZE_FORMAT,
1878 p2i(obj), (size_t)obj->size());
1879 return NULL;
1880 }
1881
1882 int hash = obj->identity_hash();
1883 oop archived_oop = (oop)G1CollectedHeap::heap()->archive_mem_allocate(len);
1884 if (archived_oop != NULL) {
1885 Copy::aligned_disjoint_words((HeapWord*)obj, (HeapWord*)archived_oop, len);
1886 relocate_klass_ptr(archived_oop);
1887 ArchivedObjectCache* cache = MetaspaceShared::archive_object_cache();
1888 cache->put(obj, archived_oop);
1889 log_debug(cds, heap)("Archived heap object " PTR_FORMAT " ==> " PTR_FORMAT,
1890 p2i(obj), p2i(archived_oop));
1891 } else {
1892 log_error(cds, heap)(
1893 "Cannot allocate space for object " PTR_FORMAT " in archived heap region",
1894 p2i(obj));
1895 vm_exit(1);
1896 }
1897 return archived_oop;
1898 }
1899
1900 oop MetaspaceShared::materialize_archived_object(oop obj) {
1901 if (obj != NULL) {
1902 return G1CollectedHeap::heap()->materialize_archived_object(obj);
1903 }
1904 return NULL;
1905 }
1906
1907 void MetaspaceShared::archive_klass_objects(Thread* THREAD) {
1908 int i;
1909 for (i = 0; i < _global_klass_objects->length(); i++) {
1910 Klass* k = _global_klass_objects->at(i);
1911
1912 // archive mirror object
1913 java_lang_Class::archive_mirror(k, CHECK);
1914
1915 // archive the resolved_referenes array
1916 if (k->is_instance_klass()) {
1917 InstanceKlass* ik = InstanceKlass::cast(k);
1918 ik->constants()->archive_resolved_references(THREAD);
1919 }
1920 }
1921 }
1922
1923 bool MetaspaceShared::is_archive_object(oop p) {
1924 return (p == NULL) ? false : G1ArchiveAllocator::is_archive_object(p);
1925 }
1926
1927 void MetaspaceShared::fixup_mapped_heap_regions() {
1928 FileMapInfo *mapinfo = FileMapInfo::current_info();
1929 mapinfo->fixup_mapped_heap_regions();
1930 }
1931 #endif // INCLUDE_CDS_JAVA_HEAP
1932
1933 // Closure for serializing initialization data in from a data area
1934 // (ptr_array) read from the shared file.
1935
1936 class ReadClosure : public SerializeClosure {
1937 private:
1938 intptr_t** _ptr_array;
1939
1940 inline intptr_t nextPtr() {
1941 return *(*_ptr_array)++;
1942 }
1943
1944 public:
1945 ReadClosure(intptr_t** ptr_array) { _ptr_array = ptr_array; }
1946
1947 void do_ptr(void** p) {
1948 assert(*p == NULL, "initializing previous initialized pointer.");
1949 intptr_t obj = nextPtr();
1950 assert((intptr_t)obj >= 0 || (intptr_t)obj < -100,
1951 "hit tag while initializing ptrs.");
1952 *p = (void*)obj;
1953 }
1954
1955 void do_u4(u4* p) {
1956 intptr_t obj = nextPtr();
1957 *p = (u4)(uintx(obj));
1958 }
1959
1960 void do_tag(int tag) {
1961 int old_tag;
1962 old_tag = (int)(intptr_t)nextPtr();
1963 // do_int(&old_tag);
1964 assert(tag == old_tag, "old tag doesn't match");
1965 FileMapInfo::assert_mark(tag == old_tag);
1966 }
1967
1968 void do_oop(oop *p) {
1969 narrowOop o = (narrowOop)nextPtr();
1970 if (o == 0 || !MetaspaceShared::open_archive_heap_region_mapped()) {
1971 p = NULL;
1972 } else {
1973 assert(MetaspaceShared::is_heap_object_archiving_allowed(),
1974 "Archived heap object is not allowed");
1975 assert(MetaspaceShared::open_archive_heap_region_mapped(),
1976 "Open archive heap region is not mapped");
1977 *p = CompressedOops::decode_not_null(o);
1978 }
1979 }
1980
1981 void do_region(u_char* start, size_t size) {
1982 assert((intptr_t)start % sizeof(intptr_t) == 0, "bad alignment");
1983 assert(size % sizeof(intptr_t) == 0, "bad size");
1984 do_tag((int)size);
1985 while (size > 0) {
1986 *(intptr_t*)start = nextPtr();
1987 start += sizeof(intptr_t);
1988 size -= sizeof(intptr_t);
1989 }
1990 }
1991
1992 bool reading() const { return true; }
1993 };
1994
1995 // Return true if given address is in the misc data region
1996 bool MetaspaceShared::is_in_shared_region(const void* p, int idx) {
1997 return UseSharedSpaces && FileMapInfo::current_info()->is_in_shared_region(p, idx);
1998 }
1999
2000 bool MetaspaceShared::is_in_trampoline_frame(address addr) {
2001 if (UseSharedSpaces && is_in_shared_region(addr, MetaspaceShared::mc)) {
2002 return true;
2003 }
2004 return false;
2005 }
2006
2007 void MetaspaceShared::print_shared_spaces() {
2008 if (UseSharedSpaces) {
2009 FileMapInfo::current_info()->print_shared_spaces();
2010 }
2011 }
2012
2013
2014 // Map shared spaces at requested addresses and return if succeeded.
2015 bool MetaspaceShared::map_shared_spaces(FileMapInfo* mapinfo) {
2016 size_t image_alignment = mapinfo->alignment();
2017
2018 #ifndef _WINDOWS
2019 // Map in the shared memory and then map the regions on top of it.
2020 // On Windows, don't map the memory here because it will cause the
2021 // mappings of the regions to fail.
2022 ReservedSpace shared_rs = mapinfo->reserve_shared_memory();
2023 if (!shared_rs.is_reserved()) return false;
2024 #endif
2025
2026 assert(!DumpSharedSpaces, "Should not be called with DumpSharedSpaces");
2027
2028 char* ro_base = NULL; char* ro_top;
2029 char* rw_base = NULL; char* rw_top;
2030 char* mc_base = NULL; char* mc_top;
2031 char* md_base = NULL; char* md_top;
2032 char* od_base = NULL; char* od_top;
2033
2034 // Map each shared region
2035 if ((mc_base = mapinfo->map_region(mc, &mc_top)) != NULL &&
2036 (rw_base = mapinfo->map_region(rw, &rw_top)) != NULL &&
2037 (ro_base = mapinfo->map_region(ro, &ro_top)) != NULL &&
2038 (md_base = mapinfo->map_region(md, &md_top)) != NULL &&
2039 (od_base = mapinfo->map_region(od, &od_top)) != NULL &&
2040 (image_alignment == (size_t)os::vm_allocation_granularity()) &&
2041 mapinfo->validate_shared_path_table()) {
2042 // Success -- set up MetaspaceObj::_shared_metaspace_{base,top} for
2043 // fast checking in MetaspaceShared::is_in_shared_metaspace() and
2044 // MetaspaceObj::is_shared().
2045 //
2046 // We require that mc->rw->ro->md->od to be laid out consecutively, with no
2047 // gaps between them. That way, we can ensure that the OS won't be able to
2048 // allocate any new memory spaces inside _shared_metaspace_{base,top}, which
2049 // would mess up the simple comparision in MetaspaceShared::is_in_shared_metaspace().
2050 assert(mc_base < ro_base && mc_base < rw_base && mc_base < md_base && mc_base < od_base, "must be");
2051 assert(od_top > ro_top && od_top > rw_top && od_top > md_top && od_top > mc_top , "must be");
2052 assert(mc_top == rw_base, "must be");
2053 assert(rw_top == ro_base, "must be");
2054 assert(ro_top == md_base, "must be");
2055 assert(md_top == od_base, "must be");
2056
2057 MetaspaceObj::set_shared_metaspace_range((void*)mc_base, (void*)od_top);
2058 return true;
2059 } else {
2060 // If there was a failure in mapping any of the spaces, unmap the ones
2061 // that succeeded
2062 if (ro_base != NULL) mapinfo->unmap_region(ro);
2063 if (rw_base != NULL) mapinfo->unmap_region(rw);
2064 if (mc_base != NULL) mapinfo->unmap_region(mc);
2065 if (md_base != NULL) mapinfo->unmap_region(md);
2066 if (od_base != NULL) mapinfo->unmap_region(od);
2067 #ifndef _WINDOWS
2068 // Release the entire mapped region
2069 shared_rs.release();
2070 #endif
2071 // If -Xshare:on is specified, print out the error message and exit VM,
2072 // otherwise, set UseSharedSpaces to false and continue.
2073 if (RequireSharedSpaces || PrintSharedArchiveAndExit) {
2074 vm_exit_during_initialization("Unable to use shared archive.", "Failed map_region for using -Xshare:on.");
2075 } else {
2076 FLAG_SET_DEFAULT(UseSharedSpaces, false);
2077 }
2078 return false;
2079 }
2080 }
2081
2082 // Read the miscellaneous data from the shared file, and
2083 // serialize it out to its various destinations.
2084
2085 void MetaspaceShared::initialize_shared_spaces() {
2086 FileMapInfo *mapinfo = FileMapInfo::current_info();
2087 _cds_i2i_entry_code_buffers = mapinfo->cds_i2i_entry_code_buffers();
2088 _cds_i2i_entry_code_buffers_size = mapinfo->cds_i2i_entry_code_buffers_size();
2089 _core_spaces_size = mapinfo->core_spaces_size();
2090 char* buffer = mapinfo->misc_data_patching_start();
2091 clone_cpp_vtables((intptr_t*)buffer);
2092
2093 // The rest of the data is now stored in the RW region
2094 buffer = mapinfo->read_only_tables_start();
2095 int sharedDictionaryLen = *(intptr_t*)buffer;
2096 buffer += sizeof(intptr_t);
2097 int number_of_entries = *(intptr_t*)buffer;
2098 buffer += sizeof(intptr_t);
2099 SystemDictionary::set_shared_dictionary((HashtableBucket<mtClass>*)buffer,
2100 sharedDictionaryLen,
2101 number_of_entries);
2102 buffer += sharedDictionaryLen;
2103
2104 // The following data are the linked list elements
2105 // (HashtableEntry objects) for the shared dictionary table.
2106
2107 int len = *(intptr_t*)buffer; // skip over shared dictionary entries
2108 buffer += sizeof(intptr_t);
2109 buffer += len;
2110
2111 // The table of archived java heap object sub-graph infos
2112 buffer = HeapShared::read_archived_subgraph_infos(buffer);
2113
2114 // Verify various attributes of the archive, plus initialize the
2115 // shared string/symbol tables
2116 intptr_t* array = (intptr_t*)buffer;
2117 ReadClosure rc(&array);
2118 serialize(&rc);
2119
2120 // Initialize the run-time symbol table.
2121 SymbolTable::create_table();
2122
2123 // Close the mapinfo file
2124 mapinfo->close();
2125
2126 if (PrintSharedArchiveAndExit) {
2127 if (PrintSharedDictionary) {
2128 tty->print_cr("\nShared classes:\n");
2129 SystemDictionary::print_shared(tty);
2130 }
2131 if (_archive_loading_failed) {
2132 tty->print_cr("archive is invalid");
2133 vm_exit(1);
2134 } else {
2135 tty->print_cr("archive is valid");
2136 vm_exit(0);
2137 }
2138 }
2139 }
2140
2141 // JVM/TI RedefineClasses() support:
2142 bool MetaspaceShared::remap_shared_readonly_as_readwrite() {
2143 assert(SafepointSynchronize::is_at_safepoint(), "must be at safepoint");
2144
2145 if (UseSharedSpaces) {
2146 // remap the shared readonly space to shared readwrite, private
2147 FileMapInfo* mapinfo = FileMapInfo::current_info();
2148 if (!mapinfo->remap_shared_readonly_as_readwrite()) {
2149 return false;
2150 }
2151 _remapped_readwrite = true;
2152 }
2153 return true;
2154 }
2155
2156 void MetaspaceShared::report_out_of_space(const char* name, size_t needed_bytes) {
2157 // This is highly unlikely to happen on 64-bits because we have reserved a 4GB space.
2158 // On 32-bit we reserve only 256MB so you could run out of space with 100,000 classes
2159 // or so.
2160 _mc_region.print_out_of_space_msg(name, needed_bytes);
2161 _rw_region.print_out_of_space_msg(name, needed_bytes);
2162 _ro_region.print_out_of_space_msg(name, needed_bytes);
2163 _md_region.print_out_of_space_msg(name, needed_bytes);
2164 _od_region.print_out_of_space_msg(name, needed_bytes);
2165
2166 vm_exit_during_initialization(err_msg("Unable to allocate from '%s' region", name),
2167 "Please reduce the number of shared classes.");
2168 }