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/classLoaderDataGraph.hpp"
28 #include "classfile/classListParser.hpp"
29 #include "classfile/classLoaderExt.hpp"
30 #include "classfile/dictionary.hpp"
31 #include "classfile/loaderConstraints.hpp"
32 #include "classfile/placeholders.hpp"
33 #include "classfile/symbolTable.hpp"
34 #include "classfile/stringTable.hpp"
35 #include "classfile/systemDictionary.hpp"
36 #include "classfile/systemDictionaryShared.hpp"
37 #include "code/codeCache.hpp"
38 #include "interpreter/bytecodeStream.hpp"
39 #include "interpreter/bytecodes.hpp"
40 #include "logging/log.hpp"
41 #include "logging/logMessage.hpp"
42 #include "memory/filemap.hpp"
43 #include "memory/heapShared.inline.hpp"
44 #include "memory/metaspace.hpp"
45 #include "memory/metaspaceClosure.hpp"
46 #include "memory/metaspaceShared.hpp"
47 #include "memory/resourceArea.hpp"
48 #include "oops/compressedOops.inline.hpp"
49 #include "oops/instanceClassLoaderKlass.hpp"
50 #include "oops/instanceMirrorKlass.hpp"
51 #include "oops/instanceRefKlass.hpp"
52 #include "oops/objArrayKlass.hpp"
53 #include "oops/objArrayOop.hpp"
54 #include "oops/oop.inline.hpp"
55 #include "oops/typeArrayKlass.hpp"
56 #include "prims/jvmtiRedefineClasses.hpp"
57 #include "runtime/handles.inline.hpp"
58 #include "runtime/os.hpp"
59 #include "runtime/safepointVerifiers.hpp"
60 #include "runtime/signature.hpp"
61 #include "runtime/timerTrace.hpp"
62 #include "runtime/vmThread.hpp"
63 #include "runtime/vm_operations.hpp"
64 #include "utilities/align.hpp"
65 #include "utilities/bitMap.hpp"
66 #include "utilities/defaultStream.hpp"
67 #include "utilities/hashtable.inline.hpp"
68 #if INCLUDE_G1GC
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 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 HeapShared::archive_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->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 log_info(cds)("narrow_klass_base = " PTR_FORMAT ", narrow_klass_shift = %d",
313 p2i(Universe::narrow_klass_base()), Universe::narrow_klass_shift());
314
315 log_info(cds)("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);
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 InstanceMirrorKlass::serialize_offsets(soc);
428 soc->do_tag(--tag);
429
430 soc->do_tag(666);
431 }
432
433 address MetaspaceShared::cds_i2i_entry_code_buffers(size_t total_size) {
434 if (DumpSharedSpaces) {
435 if (_cds_i2i_entry_code_buffers == NULL) {
436 _cds_i2i_entry_code_buffers = (address)misc_code_space_alloc(total_size);
437 _cds_i2i_entry_code_buffers_size = total_size;
438 }
439 } else if (UseSharedSpaces) {
440 assert(_cds_i2i_entry_code_buffers != NULL, "must already been initialized");
441 } else {
442 return NULL;
443 }
444
445 assert(_cds_i2i_entry_code_buffers_size == total_size, "must not change");
446 return _cds_i2i_entry_code_buffers;
447 }
448
449 // CDS code for dumping shared archive.
450
451 // Global object for holding classes that have been loaded. Since this
452 // is run at a safepoint just before exit, this is the entire set of classes.
453 static GrowableArray<Klass*>* _global_klass_objects;
454
455 GrowableArray<Klass*>* MetaspaceShared::collected_klasses() {
456 return _global_klass_objects;
457 }
458
459 static void collect_array_classes(Klass* k) {
460 _global_klass_objects->append_if_missing(k);
461 if (k->is_array_klass()) {
462 // Add in the array classes too
463 ArrayKlass* ak = ArrayKlass::cast(k);
464 Klass* h = ak->higher_dimension();
465 if (h != NULL) {
466 h->array_klasses_do(collect_array_classes);
467 }
468 }
469 }
470
471 class CollectClassesClosure : public KlassClosure {
472 void do_klass(Klass* k) {
473 if (!(k->is_instance_klass() && InstanceKlass::cast(k)->is_in_error_state())) {
474 if (k->is_instance_klass() && InstanceKlass::cast(k)->signers() != NULL) {
475 // Mark any class with signers and don't add to the _global_klass_objects
476 k->set_has_signer_and_not_archived();
477 } else {
478 _global_klass_objects->append_if_missing(k);
479 }
480 }
481 if (k->is_array_klass()) {
482 // Add in the array classes too
483 ArrayKlass* ak = ArrayKlass::cast(k);
484 Klass* h = ak->higher_dimension();
485 if (h != NULL) {
486 h->array_klasses_do(collect_array_classes);
487 }
488 }
489 }
490 };
491
492 static void remove_unshareable_in_classes() {
493 for (int i = 0; i < _global_klass_objects->length(); i++) {
494 Klass* k = _global_klass_objects->at(i);
495 if (!k->is_objArray_klass()) {
496 // InstanceKlass and TypeArrayKlass will in turn call remove_unshareable_info
497 // on their array classes.
498 assert(k->is_instance_klass() || k->is_typeArray_klass(), "must be");
499 k->remove_unshareable_info();
500 }
501 }
502 }
503
504 static void remove_java_mirror_in_classes() {
505 for (int i = 0; i < _global_klass_objects->length(); i++) {
506 Klass* k = _global_klass_objects->at(i);
507 if (!k->is_objArray_klass()) {
508 // InstanceKlass and TypeArrayKlass will in turn call remove_unshareable_info
509 // on their array classes.
510 assert(k->is_instance_klass() || k->is_typeArray_klass(), "must be");
511 k->remove_java_mirror();
512 }
513 }
514 }
515
516 static void clear_basic_type_mirrors() {
517 assert(!HeapShared::is_heap_object_archiving_allowed(), "Sanity");
518 Universe::set_int_mirror(NULL);
519 Universe::set_float_mirror(NULL);
520 Universe::set_double_mirror(NULL);
521 Universe::set_byte_mirror(NULL);
522 Universe::set_bool_mirror(NULL);
523 Universe::set_char_mirror(NULL);
524 Universe::set_long_mirror(NULL);
525 Universe::set_short_mirror(NULL);
526 Universe::set_void_mirror(NULL);
527 }
528
529 static void rewrite_nofast_bytecode(Method* method) {
530 BytecodeStream bcs(method);
531 while (!bcs.is_last_bytecode()) {
532 Bytecodes::Code opcode = bcs.next();
533 switch (opcode) {
534 case Bytecodes::_getfield: *bcs.bcp() = Bytecodes::_nofast_getfield; break;
535 case Bytecodes::_putfield: *bcs.bcp() = Bytecodes::_nofast_putfield; break;
536 case Bytecodes::_aload_0: *bcs.bcp() = Bytecodes::_nofast_aload_0; break;
537 case Bytecodes::_iload: {
538 if (!bcs.is_wide()) {
539 *bcs.bcp() = Bytecodes::_nofast_iload;
540 }
541 break;
542 }
543 default: break;
544 }
545 }
546 }
547
548 // Walk all methods in the class list to ensure that they won't be modified at
549 // run time. This includes:
550 // [1] Rewrite all bytecodes as needed, so that the ConstMethod* will not be modified
551 // at run time by RewriteBytecodes/RewriteFrequentPairs
552 // [2] Assign a fingerprint, so one doesn't need to be assigned at run-time.
553 static void rewrite_nofast_bytecodes_and_calculate_fingerprints() {
554 for (int i = 0; i < _global_klass_objects->length(); i++) {
555 Klass* k = _global_klass_objects->at(i);
556 if (k->is_instance_klass()) {
557 InstanceKlass* ik = InstanceKlass::cast(k);
558 for (int i = 0; i < ik->methods()->length(); i++) {
559 Method* m = ik->methods()->at(i);
560 rewrite_nofast_bytecode(m);
561 Fingerprinter fp(m);
562 // The side effect of this call sets method's fingerprint field.
563 fp.fingerprint();
564 }
565 }
566 }
567 }
568
569 static void relocate_cached_class_file() {
570 for (int i = 0; i < _global_klass_objects->length(); i++) {
571 Klass* k = _global_klass_objects->at(i);
572 if (k->is_instance_klass()) {
573 InstanceKlass* ik = InstanceKlass::cast(k);
574 JvmtiCachedClassFileData* p = ik->get_archived_class_data();
575 if (p != NULL) {
576 int size = offset_of(JvmtiCachedClassFileData, data) + p->length;
577 JvmtiCachedClassFileData* q = (JvmtiCachedClassFileData*)_od_region.allocate(size);
578 q->length = p->length;
579 memcpy(q->data, p->data, p->length);
580 ik->set_archived_class_data(q);
581 }
582 }
583 }
584 }
585
586 NOT_PRODUCT(
587 static void assert_not_unsafe_anonymous_class(InstanceKlass* k) {
588 assert(!(k->is_unsafe_anonymous()), "cannot archive unsafe anonymous classes");
589 }
590
591 // Unsafe anonymous classes are not stored inside any dictionaries.
592 static void assert_no_unsafe_anonymous_classes_in_dictionaries() {
593 ClassLoaderDataGraph::dictionary_classes_do(assert_not_unsafe_anonymous_class);
594 })
595
596 // Objects of the Metadata types (such as Klass and ConstantPool) have C++ vtables.
597 // (In GCC this is the field <Type>::_vptr, i.e., first word in the object.)
598 //
599 // Addresses of the vtables and the methods may be different across JVM runs,
600 // if libjvm.so is dynamically loaded at a different base address.
601 //
602 // To ensure that the Metadata objects in the CDS archive always have the correct vtable:
603 //
604 // + at dump time: we redirect the _vptr to point to our own vtables inside
605 // the CDS image
606 // + at run time: we clone the actual contents of the vtables from libjvm.so
607 // into our own tables.
608
609 // Currently, the archive contain ONLY the following types of objects that have C++ vtables.
610 #define CPP_VTABLE_PATCH_TYPES_DO(f) \
611 f(ConstantPool) \
612 f(InstanceKlass) \
613 f(InstanceClassLoaderKlass) \
614 f(InstanceMirrorKlass) \
615 f(InstanceRefKlass) \
616 f(Method) \
617 f(ObjArrayKlass) \
618 f(TypeArrayKlass)
619
620 class CppVtableInfo {
621 intptr_t _vtable_size;
622 intptr_t _cloned_vtable[1];
623 public:
624 static int num_slots(int vtable_size) {
625 return 1 + vtable_size; // Need to add the space occupied by _vtable_size;
626 }
627 int vtable_size() { return int(uintx(_vtable_size)); }
628 void set_vtable_size(int n) { _vtable_size = intptr_t(n); }
629 intptr_t* cloned_vtable() { return &_cloned_vtable[0]; }
630 void zero() { memset(_cloned_vtable, 0, sizeof(intptr_t) * vtable_size()); }
631 // Returns the address of the next CppVtableInfo that can be placed immediately after this CppVtableInfo
632 static size_t byte_size(int vtable_size) {
633 CppVtableInfo i;
634 return pointer_delta(&i._cloned_vtable[vtable_size], &i, sizeof(u1));
635 }
636 };
637
638 template <class T> class CppVtableCloner : public T {
639 static intptr_t* vtable_of(Metadata& m) {
640 return *((intptr_t**)&m);
641 }
642 static CppVtableInfo* _info;
643
644 static int get_vtable_length(const char* name);
645
646 public:
647 // Allocate and initialize the C++ vtable, starting from top, but do not go past end.
648 static intptr_t* allocate(const char* name);
649
650 // Clone the vtable to ...
651 static intptr_t* clone_vtable(const char* name, CppVtableInfo* info);
652
653 static void zero_vtable_clone() {
654 assert(DumpSharedSpaces, "dump-time only");
655 _info->zero();
656 }
657
658 // Switch the vtable pointer to point to the cloned vtable.
659 static void patch(Metadata* obj) {
660 assert(DumpSharedSpaces, "dump-time only");
661 *(void**)obj = (void*)(_info->cloned_vtable());
662 }
663
664 static bool is_valid_shared_object(const T* obj) {
665 intptr_t* vptr = *(intptr_t**)obj;
666 return vptr == _info->cloned_vtable();
667 }
668 };
669
670 template <class T> CppVtableInfo* CppVtableCloner<T>::_info = NULL;
671
672 template <class T>
673 intptr_t* CppVtableCloner<T>::allocate(const char* name) {
674 assert(is_aligned(_md_region.top(), sizeof(intptr_t)), "bad alignment");
675 int n = get_vtable_length(name);
676 _info = (CppVtableInfo*)_md_region.allocate(CppVtableInfo::byte_size(n), sizeof(intptr_t));
677 _info->set_vtable_size(n);
678
679 intptr_t* p = clone_vtable(name, _info);
680 assert((char*)p == _md_region.top(), "must be");
681
682 return p;
683 }
684
685 template <class T>
686 intptr_t* CppVtableCloner<T>::clone_vtable(const char* name, CppVtableInfo* info) {
687 if (!DumpSharedSpaces) {
688 assert(_info == 0, "_info is initialized only at dump time");
689 _info = info; // Remember it -- it will be used by MetaspaceShared::is_valid_shared_method()
690 }
691 T tmp; // Allocate temporary dummy metadata object to get to the original vtable.
692 int n = info->vtable_size();
693 intptr_t* srcvtable = vtable_of(tmp);
694 intptr_t* dstvtable = info->cloned_vtable();
695
696 // We already checked (and, if necessary, adjusted n) when the vtables were allocated, so we are
697 // safe to do memcpy.
698 log_debug(cds, vtables)("Copying %3d vtable entries for %s", n, name);
699 memcpy(dstvtable, srcvtable, sizeof(intptr_t) * n);
700 return dstvtable + n;
701 }
702
703 // To determine the size of the vtable for each type, we use the following
704 // trick by declaring 2 subclasses:
705 //
706 // class CppVtableTesterA: public InstanceKlass {virtual int last_virtual_method() {return 1;} };
707 // class CppVtableTesterB: public InstanceKlass {virtual void* last_virtual_method() {return NULL}; };
708 //
709 // CppVtableTesterA and CppVtableTesterB's vtables have the following properties:
710 // - Their size (N+1) is exactly one more than the size of InstanceKlass's vtable (N)
711 // - The first N entries have are exactly the same as in InstanceKlass's vtable.
712 // - Their last entry is different.
713 //
714 // So to determine the value of N, we just walk CppVtableTesterA and CppVtableTesterB's tables
715 // and find the first entry that's different.
716 //
717 // This works on all C++ compilers supported by Oracle, but you may need to tweak it for more
718 // esoteric compilers.
719
720 template <class T> class CppVtableTesterB: public T {
721 public:
722 virtual int last_virtual_method() {return 1;}
723 };
724
725 template <class T> class CppVtableTesterA : public T {
726 public:
727 virtual void* last_virtual_method() {
728 // Make this different than CppVtableTesterB::last_virtual_method so the C++
729 // compiler/linker won't alias the two functions.
730 return NULL;
731 }
732 };
733
734 template <class T>
735 int CppVtableCloner<T>::get_vtable_length(const char* name) {
736 CppVtableTesterA<T> a;
737 CppVtableTesterB<T> b;
738
739 intptr_t* avtable = vtable_of(a);
740 intptr_t* bvtable = vtable_of(b);
741
742 // Start at slot 1, because slot 0 may be RTTI (on Solaris/Sparc)
743 int vtable_len = 1;
744 for (; ; vtable_len++) {
745 if (avtable[vtable_len] != bvtable[vtable_len]) {
746 break;
747 }
748 }
749 log_debug(cds, vtables)("Found %3d vtable entries for %s", vtable_len, name);
750
751 return vtable_len;
752 }
753
754 #define ALLOC_CPP_VTABLE_CLONE(c) \
755 CppVtableCloner<c>::allocate(#c);
756
757 #define CLONE_CPP_VTABLE(c) \
758 p = CppVtableCloner<c>::clone_vtable(#c, (CppVtableInfo*)p);
759
760 #define ZERO_CPP_VTABLE(c) \
761 CppVtableCloner<c>::zero_vtable_clone();
762
763 // This can be called at both dump time and run time.
764 intptr_t* MetaspaceShared::clone_cpp_vtables(intptr_t* p) {
765 assert(DumpSharedSpaces || UseSharedSpaces, "sanity");
766 CPP_VTABLE_PATCH_TYPES_DO(CLONE_CPP_VTABLE);
767 return p;
768 }
769
770 void MetaspaceShared::zero_cpp_vtable_clones_for_writing() {
771 assert(DumpSharedSpaces, "dump-time only");
772 CPP_VTABLE_PATCH_TYPES_DO(ZERO_CPP_VTABLE);
773 }
774
775 // Allocate and initialize the C++ vtables, starting from top, but do not go past end.
776 void MetaspaceShared::allocate_cpp_vtable_clones() {
777 assert(DumpSharedSpaces, "dump-time only");
778 // Layout (each slot is a intptr_t):
779 // [number of slots in the first vtable = n1]
780 // [ <n1> slots for the first vtable]
781 // [number of slots in the first second = n2]
782 // [ <n2> slots for the second vtable]
783 // ...
784 // The order of the vtables is the same as the CPP_VTAB_PATCH_TYPES_DO macro.
785 CPP_VTABLE_PATCH_TYPES_DO(ALLOC_CPP_VTABLE_CLONE);
786 }
787
788 // Switch the vtable pointer to point to the cloned vtable. We assume the
789 // vtable pointer is in first slot in object.
790 void MetaspaceShared::patch_cpp_vtable_pointers() {
791 int n = _global_klass_objects->length();
792 for (int i = 0; i < n; i++) {
793 Klass* obj = _global_klass_objects->at(i);
794 if (obj->is_instance_klass()) {
795 InstanceKlass* ik = InstanceKlass::cast(obj);
796 if (ik->is_class_loader_instance_klass()) {
797 CppVtableCloner<InstanceClassLoaderKlass>::patch(ik);
798 } else if (ik->is_reference_instance_klass()) {
799 CppVtableCloner<InstanceRefKlass>::patch(ik);
800 } else if (ik->is_mirror_instance_klass()) {
801 CppVtableCloner<InstanceMirrorKlass>::patch(ik);
802 } else {
803 CppVtableCloner<InstanceKlass>::patch(ik);
804 }
805 ConstantPool* cp = ik->constants();
806 CppVtableCloner<ConstantPool>::patch(cp);
807 for (int j = 0; j < ik->methods()->length(); j++) {
808 Method* m = ik->methods()->at(j);
809 CppVtableCloner<Method>::patch(m);
810 assert(CppVtableCloner<Method>::is_valid_shared_object(m), "must be");
811 }
812 } else if (obj->is_objArray_klass()) {
813 CppVtableCloner<ObjArrayKlass>::patch(obj);
814 } else {
815 assert(obj->is_typeArray_klass(), "sanity");
816 CppVtableCloner<TypeArrayKlass>::patch(obj);
817 }
818 }
819 }
820
821 bool MetaspaceShared::is_valid_shared_method(const Method* m) {
822 assert(is_in_shared_metaspace(m), "must be");
823 return CppVtableCloner<Method>::is_valid_shared_object(m);
824 }
825
826 // Closure for serializing initialization data out to a data area to be
827 // written to the shared file.
828
829 class WriteClosure : public SerializeClosure {
830 private:
831 DumpRegion* _dump_region;
832
833 public:
834 WriteClosure(DumpRegion* r) {
835 _dump_region = r;
836 }
837
838 void do_ptr(void** p) {
839 _dump_region->append_intptr_t((intptr_t)*p);
840 }
841
842 void do_u4(u4* p) {
843 void* ptr = (void*)(uintx(*p));
844 do_ptr(&ptr);
845 }
846
847 void do_tag(int tag) {
848 _dump_region->append_intptr_t((intptr_t)tag);
849 }
850
851 void do_oop(oop* o) {
852 if (*o == NULL) {
853 _dump_region->append_intptr_t(0);
854 } else {
855 assert(HeapShared::is_heap_object_archiving_allowed(),
856 "Archiving heap object is not allowed");
857 _dump_region->append_intptr_t(
858 (intptr_t)CompressedOops::encode_not_null(*o));
859 }
860 }
861
862 void do_region(u_char* start, size_t size) {
863 assert((intptr_t)start % sizeof(intptr_t) == 0, "bad alignment");
864 assert(size % sizeof(intptr_t) == 0, "bad size");
865 do_tag((int)size);
866 while (size > 0) {
867 _dump_region->append_intptr_t(*(intptr_t*)start);
868 start += sizeof(intptr_t);
869 size -= sizeof(intptr_t);
870 }
871 }
872
873 bool reading() const { return false; }
874 };
875
876 // This is for dumping detailed statistics for the allocations
877 // in the shared spaces.
878 class DumpAllocStats : public ResourceObj {
879 public:
880
881 // Here's poor man's enum inheritance
882 #define SHAREDSPACE_OBJ_TYPES_DO(f) \
883 METASPACE_OBJ_TYPES_DO(f) \
884 f(SymbolHashentry) \
885 f(SymbolBucket) \
886 f(StringHashentry) \
887 f(StringBucket) \
888 f(Other)
889
890 enum Type {
891 // Types are MetaspaceObj::ClassType, MetaspaceObj::SymbolType, etc
892 SHAREDSPACE_OBJ_TYPES_DO(METASPACE_OBJ_TYPE_DECLARE)
893 _number_of_types
894 };
895
896 static const char * type_name(Type type) {
897 switch(type) {
898 SHAREDSPACE_OBJ_TYPES_DO(METASPACE_OBJ_TYPE_NAME_CASE)
899 default:
900 ShouldNotReachHere();
901 return NULL;
902 }
903 }
904
905 public:
906 enum { RO = 0, RW = 1 };
907
908 int _counts[2][_number_of_types];
909 int _bytes [2][_number_of_types];
910
911 DumpAllocStats() {
912 memset(_counts, 0, sizeof(_counts));
913 memset(_bytes, 0, sizeof(_bytes));
914 };
915
916 void record(MetaspaceObj::Type type, int byte_size, bool read_only) {
917 assert(int(type) >= 0 && type < MetaspaceObj::_number_of_types, "sanity");
918 int which = (read_only) ? RO : RW;
919 _counts[which][type] ++;
920 _bytes [which][type] += byte_size;
921 }
922
923 void record_other_type(int byte_size, bool read_only) {
924 int which = (read_only) ? RO : RW;
925 _bytes [which][OtherType] += byte_size;
926 }
927 void print_stats(int ro_all, int rw_all, int mc_all, int md_all);
928 };
929
930 void DumpAllocStats::print_stats(int ro_all, int rw_all, int mc_all, int md_all) {
931 // Calculate size of data that was not allocated by Metaspace::allocate()
932 MetaspaceSharedStats *stats = MetaspaceShared::stats();
933
934 // symbols
935 _counts[RO][SymbolHashentryType] = stats->symbol.hashentry_count;
936 _bytes [RO][SymbolHashentryType] = stats->symbol.hashentry_bytes;
937
938 _counts[RO][SymbolBucketType] = stats->symbol.bucket_count;
939 _bytes [RO][SymbolBucketType] = stats->symbol.bucket_bytes;
940
941 // strings
942 _counts[RO][StringHashentryType] = stats->string.hashentry_count;
943 _bytes [RO][StringHashentryType] = stats->string.hashentry_bytes;
944
945 _counts[RO][StringBucketType] = stats->string.bucket_count;
946 _bytes [RO][StringBucketType] = stats->string.bucket_bytes;
947
948 // TODO: count things like dictionary, vtable, etc
949 _bytes[RW][OtherType] += mc_all + md_all;
950 rw_all += mc_all + md_all; // mc/md are mapped Read/Write
951
952 // prevent divide-by-zero
953 if (ro_all < 1) {
954 ro_all = 1;
955 }
956 if (rw_all < 1) {
957 rw_all = 1;
958 }
959
960 int all_ro_count = 0;
961 int all_ro_bytes = 0;
962 int all_rw_count = 0;
963 int all_rw_bytes = 0;
964
965 // To make fmt_stats be a syntactic constant (for format warnings), use #define.
966 #define fmt_stats "%-20s: %8d %10d %5.1f | %8d %10d %5.1f | %8d %10d %5.1f"
967 const char *sep = "--------------------+---------------------------+---------------------------+--------------------------";
968 const char *hdr = " ro_cnt ro_bytes % | rw_cnt rw_bytes % | all_cnt all_bytes %";
969
970 LogMessage(cds) msg;
971
972 msg.info("Detailed metadata info (excluding od/st regions; rw stats include md/mc regions):");
973 msg.info("%s", hdr);
974 msg.info("%s", sep);
975 for (int type = 0; type < int(_number_of_types); type ++) {
976 const char *name = type_name((Type)type);
977 int ro_count = _counts[RO][type];
978 int ro_bytes = _bytes [RO][type];
979 int rw_count = _counts[RW][type];
980 int rw_bytes = _bytes [RW][type];
981 int count = ro_count + rw_count;
982 int bytes = ro_bytes + rw_bytes;
983
984 double ro_perc = percent_of(ro_bytes, ro_all);
985 double rw_perc = percent_of(rw_bytes, rw_all);
986 double perc = percent_of(bytes, ro_all + rw_all);
987
988 msg.info(fmt_stats, name,
989 ro_count, ro_bytes, ro_perc,
990 rw_count, rw_bytes, rw_perc,
991 count, bytes, perc);
992
993 all_ro_count += ro_count;
994 all_ro_bytes += ro_bytes;
995 all_rw_count += rw_count;
996 all_rw_bytes += rw_bytes;
997 }
998
999 int all_count = all_ro_count + all_rw_count;
1000 int all_bytes = all_ro_bytes + all_rw_bytes;
1001
1002 double all_ro_perc = percent_of(all_ro_bytes, ro_all);
1003 double all_rw_perc = percent_of(all_rw_bytes, rw_all);
1004 double all_perc = percent_of(all_bytes, ro_all + rw_all);
1005
1006 msg.info("%s", sep);
1007 msg.info(fmt_stats, "Total",
1008 all_ro_count, all_ro_bytes, all_ro_perc,
1009 all_rw_count, all_rw_bytes, all_rw_perc,
1010 all_count, all_bytes, all_perc);
1011
1012 assert(all_ro_bytes == ro_all, "everything should have been counted");
1013 assert(all_rw_bytes == rw_all, "everything should have been counted");
1014
1015 #undef fmt_stats
1016 }
1017
1018 // Populate the shared space.
1019
1020 class VM_PopulateDumpSharedSpace: public VM_Operation {
1021 private:
1022 GrowableArray<MemRegion> *_closed_archive_heap_regions;
1023 GrowableArray<MemRegion> *_open_archive_heap_regions;
1024
1025 GrowableArray<ArchiveHeapOopmapInfo> *_closed_archive_heap_oopmaps;
1026 GrowableArray<ArchiveHeapOopmapInfo> *_open_archive_heap_oopmaps;
1027
1028 void dump_java_heap_objects() NOT_CDS_JAVA_HEAP_RETURN;
1029 void dump_archive_heap_oopmaps() NOT_CDS_JAVA_HEAP_RETURN;
1030 void dump_archive_heap_oopmaps(GrowableArray<MemRegion>* regions,
1031 GrowableArray<ArchiveHeapOopmapInfo>* oopmaps);
1032 void dump_symbols();
1033 char* dump_read_only_tables();
1034 void print_region_stats();
1035 void print_heap_region_stats(GrowableArray<MemRegion> *heap_mem,
1036 const char *name, const size_t total_size);
1037 public:
1038
1039 VMOp_Type type() const { return VMOp_PopulateDumpSharedSpace; }
1040 void doit(); // outline because gdb sucks
1041 static void write_region(FileMapInfo* mapinfo, int region, DumpRegion* space, bool read_only, bool allow_exec);
1042 bool allow_nested_vm_operations() const { return true; }
1043 }; // class VM_PopulateDumpSharedSpace
1044
1045 class SortedSymbolClosure: public SymbolClosure {
1046 GrowableArray<Symbol*> _symbols;
1047 virtual void do_symbol(Symbol** sym) {
1048 assert((*sym)->is_permanent(), "archived symbols must be permanent");
1049 _symbols.append(*sym);
1050 }
1051 static int compare_symbols_by_address(Symbol** a, Symbol** b) {
1052 if (a[0] < b[0]) {
1053 return -1;
1054 } else if (a[0] == b[0]) {
1055 return 0;
1056 } else {
1057 return 1;
1058 }
1059 }
1060
1061 public:
1062 SortedSymbolClosure() {
1063 SymbolTable::symbols_do(this);
1064 _symbols.sort(compare_symbols_by_address);
1065 }
1066 GrowableArray<Symbol*>* get_sorted_symbols() {
1067 return &_symbols;
1068 }
1069 };
1070
1071 // ArchiveCompactor --
1072 //
1073 // This class is the central piece of shared archive compaction -- all metaspace data are
1074 // initially allocated outside of the shared regions. ArchiveCompactor copies the
1075 // metaspace data into their final location in the shared regions.
1076
1077 class ArchiveCompactor : AllStatic {
1078 static DumpAllocStats* _alloc_stats;
1079 static SortedSymbolClosure* _ssc;
1080
1081 static unsigned my_hash(const address& a) {
1082 return primitive_hash<address>(a);
1083 }
1084 static bool my_equals(const address& a0, const address& a1) {
1085 return primitive_equals<address>(a0, a1);
1086 }
1087 typedef ResourceHashtable<
1088 address, address,
1089 ArchiveCompactor::my_hash, // solaris compiler doesn't like: primitive_hash<address>
1090 ArchiveCompactor::my_equals, // solaris compiler doesn't like: primitive_equals<address>
1091 16384, ResourceObj::C_HEAP> RelocationTable;
1092 static RelocationTable* _new_loc_table;
1093
1094 public:
1095 static void initialize() {
1096 _alloc_stats = new(ResourceObj::C_HEAP, mtInternal)DumpAllocStats;
1097 _new_loc_table = new(ResourceObj::C_HEAP, mtInternal)RelocationTable;
1098 }
1099 static DumpAllocStats* alloc_stats() {
1100 return _alloc_stats;
1101 }
1102
1103 static void allocate(MetaspaceClosure::Ref* ref, bool read_only) {
1104 address obj = ref->obj();
1105 int bytes = ref->size() * BytesPerWord;
1106 char* p;
1107 size_t alignment = BytesPerWord;
1108 char* oldtop;
1109 char* newtop;
1110
1111 if (read_only) {
1112 oldtop = _ro_region.top();
1113 p = _ro_region.allocate(bytes, alignment);
1114 newtop = _ro_region.top();
1115 } else {
1116 oldtop = _rw_region.top();
1117 p = _rw_region.allocate(bytes, alignment);
1118 newtop = _rw_region.top();
1119 }
1120 memcpy(p, obj, bytes);
1121 bool isnew = _new_loc_table->put(obj, (address)p);
1122 log_trace(cds)("Copy: " PTR_FORMAT " ==> " PTR_FORMAT " %d", p2i(obj), p2i(p), bytes);
1123 assert(isnew, "must be");
1124
1125 _alloc_stats->record(ref->msotype(), int(newtop - oldtop), read_only);
1126 if (ref->msotype() == MetaspaceObj::SymbolType) {
1127 uintx delta = MetaspaceShared::object_delta(p);
1128 if (delta > MAX_SHARED_DELTA) {
1129 // This is just a sanity check and should not appear in any real world usage. This
1130 // happens only if you allocate more than 2GB of Symbols and would require
1131 // millions of shared classes.
1132 vm_exit_during_initialization("Too many Symbols in the CDS archive",
1133 "Please reduce the number of shared classes.");
1134 }
1135 }
1136 }
1137
1138 static address get_new_loc(MetaspaceClosure::Ref* ref) {
1139 address* pp = _new_loc_table->get(ref->obj());
1140 assert(pp != NULL, "must be");
1141 return *pp;
1142 }
1143
1144 private:
1145 // Makes a shallow copy of visited MetaspaceObj's
1146 class ShallowCopier: public UniqueMetaspaceClosure {
1147 bool _read_only;
1148 public:
1149 ShallowCopier(bool read_only) : _read_only(read_only) {}
1150
1151 virtual void do_unique_ref(Ref* ref, bool read_only) {
1152 if (read_only == _read_only) {
1153 allocate(ref, read_only);
1154 }
1155 }
1156 };
1157
1158 // Relocate embedded pointers within a MetaspaceObj's shallow copy
1159 class ShallowCopyEmbeddedRefRelocator: public UniqueMetaspaceClosure {
1160 public:
1161 virtual void do_unique_ref(Ref* ref, bool read_only) {
1162 address new_loc = get_new_loc(ref);
1163 RefRelocator refer;
1164 ref->metaspace_pointers_do_at(&refer, new_loc);
1165 }
1166 };
1167
1168 // Relocate a reference to point to its shallow copy
1169 class RefRelocator: public MetaspaceClosure {
1170 public:
1171 virtual bool do_ref(Ref* ref, bool read_only) {
1172 if (ref->not_null()) {
1173 ref->update(get_new_loc(ref));
1174 }
1175 return false; // Do not recurse.
1176 }
1177 };
1178
1179 #ifdef ASSERT
1180 class IsRefInArchiveChecker: public MetaspaceClosure {
1181 public:
1182 virtual bool do_ref(Ref* ref, bool read_only) {
1183 if (ref->not_null()) {
1184 char* obj = (char*)ref->obj();
1185 assert(_ro_region.contains(obj) || _rw_region.contains(obj),
1186 "must be relocated to point to CDS archive");
1187 }
1188 return false; // Do not recurse.
1189 }
1190 };
1191 #endif
1192
1193 public:
1194 static void copy_and_compact() {
1195 // We should no longer allocate anything from the metaspace, so that
1196 // we can have a stable set of MetaspaceObjs to work with.
1197 Metaspace::freeze();
1198
1199 ResourceMark rm;
1200 SortedSymbolClosure the_ssc; // StackObj
1201 _ssc = &the_ssc;
1202
1203 tty->print_cr("Scanning all metaspace objects ... ");
1204 {
1205 // allocate and shallow-copy RW objects, immediately following the MC region
1206 tty->print_cr("Allocating RW objects ... ");
1207 _mc_region.pack(&_rw_region);
1208
1209 ResourceMark rm;
1210 ShallowCopier rw_copier(false);
1211 iterate_roots(&rw_copier);
1212 }
1213 {
1214 // allocate and shallow-copy of RO object, immediately following the RW region
1215 tty->print_cr("Allocating RO objects ... ");
1216 _rw_region.pack(&_ro_region);
1217
1218 ResourceMark rm;
1219 ShallowCopier ro_copier(true);
1220 iterate_roots(&ro_copier);
1221 }
1222 {
1223 tty->print_cr("Relocating embedded pointers ... ");
1224 ResourceMark rm;
1225 ShallowCopyEmbeddedRefRelocator emb_reloc;
1226 iterate_roots(&emb_reloc);
1227 }
1228 {
1229 tty->print_cr("Relocating external roots ... ");
1230 ResourceMark rm;
1231 RefRelocator ext_reloc;
1232 iterate_roots(&ext_reloc);
1233 }
1234
1235 #ifdef ASSERT
1236 {
1237 tty->print_cr("Verifying external roots ... ");
1238 ResourceMark rm;
1239 IsRefInArchiveChecker checker;
1240 iterate_roots(&checker);
1241 }
1242 #endif
1243
1244
1245 // cleanup
1246 _ssc = NULL;
1247 }
1248
1249 // We must relocate the System::_well_known_klasses only after we have copied the
1250 // java objects in during dump_java_heap_objects(): during the object copy, we operate on
1251 // old objects which assert that their klass is the original klass.
1252 static void relocate_well_known_klasses() {
1253 {
1254 tty->print_cr("Relocating SystemDictionary::_well_known_klasses[] ... ");
1255 ResourceMark rm;
1256 RefRelocator ext_reloc;
1257 SystemDictionary::well_known_klasses_do(&ext_reloc);
1258 }
1259 // NOTE: after this point, we shouldn't have any globals that can reach the old
1260 // objects.
1261
1262 // We cannot use any of the objects in the heap anymore (except for the objects
1263 // in the CDS shared string regions) because their headers no longer point to
1264 // valid Klasses.
1265 }
1266
1267 static void iterate_roots(MetaspaceClosure* it) {
1268 GrowableArray<Symbol*>* symbols = _ssc->get_sorted_symbols();
1269 for (int i=0; i<symbols->length(); i++) {
1270 it->push(symbols->adr_at(i));
1271 }
1272 if (_global_klass_objects != NULL) {
1273 // Need to fix up the pointers
1274 for (int i = 0; i < _global_klass_objects->length(); i++) {
1275 // NOTE -- this requires that the vtable is NOT yet patched, or else we are hosed.
1276 it->push(_global_klass_objects->adr_at(i));
1277 }
1278 }
1279 FileMapInfo::metaspace_pointers_do(it);
1280 SystemDictionary::classes_do(it);
1281 Universe::metaspace_pointers_do(it);
1282 SymbolTable::metaspace_pointers_do(it);
1283 vmSymbols::metaspace_pointers_do(it);
1284 }
1285
1286 static Klass* get_relocated_klass(Klass* orig_klass) {
1287 assert(DumpSharedSpaces, "dump time only");
1288 address* pp = _new_loc_table->get((address)orig_klass);
1289 assert(pp != NULL, "must be");
1290 Klass* klass = (Klass*)(*pp);
1291 assert(klass->is_klass(), "must be");
1292 return klass;
1293 }
1294 };
1295
1296 DumpAllocStats* ArchiveCompactor::_alloc_stats;
1297 SortedSymbolClosure* ArchiveCompactor::_ssc;
1298 ArchiveCompactor::RelocationTable* ArchiveCompactor::_new_loc_table;
1299
1300 void VM_PopulateDumpSharedSpace::write_region(FileMapInfo* mapinfo, int region_idx,
1301 DumpRegion* dump_region, bool read_only, bool allow_exec) {
1302 mapinfo->write_region(region_idx, dump_region->base(), dump_region->used(), read_only, allow_exec);
1303 }
1304
1305 void VM_PopulateDumpSharedSpace::dump_symbols() {
1306 tty->print_cr("Dumping symbol table ...");
1307
1308 NOT_PRODUCT(SymbolTable::verify());
1309 SymbolTable::write_to_archive();
1310 }
1311
1312 char* VM_PopulateDumpSharedSpace::dump_read_only_tables() {
1313 char* oldtop = _ro_region.top();
1314 // Reorder the system dictionary. Moving the symbols affects
1315 // how the hash table indices are calculated.
1316 SystemDictionary::reorder_dictionary_for_sharing();
1317
1318 tty->print("Removing java_mirror ... ");
1319 if (!HeapShared::is_heap_object_archiving_allowed()) {
1320 clear_basic_type_mirrors();
1321 }
1322 remove_java_mirror_in_classes();
1323 tty->print_cr("done. ");
1324 NOT_PRODUCT(SystemDictionary::verify();)
1325
1326 size_t buckets_bytes = SystemDictionary::count_bytes_for_buckets();
1327 char* buckets_top = _ro_region.allocate(buckets_bytes, sizeof(intptr_t));
1328 SystemDictionary::copy_buckets(buckets_top, _ro_region.top());
1329
1330 size_t table_bytes = SystemDictionary::count_bytes_for_table();
1331 char* table_top = _ro_region.allocate(table_bytes, sizeof(intptr_t));
1332 SystemDictionary::copy_table(table_top, _ro_region.top());
1333
1334 // Write the archived object sub-graph infos. For each klass with sub-graphs,
1335 // the info includes the static fields (sub-graph entry points) and Klasses
1336 // of objects included in the sub-graph.
1337 HeapShared::write_archived_subgraph_infos();
1338
1339 // Write the other data to the output array.
1340 WriteClosure wc(&_ro_region);
1341 MetaspaceShared::serialize(&wc);
1342
1343 // Write the bitmaps for patching the archive heap regions
1344 dump_archive_heap_oopmaps();
1345
1346 char* newtop = _ro_region.top();
1347 ArchiveCompactor::alloc_stats()->record_other_type(int(newtop - oldtop), true);
1348 return buckets_top;
1349 }
1350
1351 void VM_PopulateDumpSharedSpace::doit() {
1352 Thread* THREAD = VMThread::vm_thread();
1353
1354 FileMapInfo::check_nonempty_dir_in_shared_path_table();
1355
1356 NOT_PRODUCT(SystemDictionary::verify();)
1357 // The following guarantee is meant to ensure that no loader constraints
1358 // exist yet, since the constraints table is not shared. This becomes
1359 // more important now that we don't re-initialize vtables/itables for
1360 // shared classes at runtime, where constraints were previously created.
1361 guarantee(SystemDictionary::constraints()->number_of_entries() == 0,
1362 "loader constraints are not saved");
1363 guarantee(SystemDictionary::placeholders()->number_of_entries() == 0,
1364 "placeholders are not saved");
1365 // Revisit and implement this if we prelink method handle call sites:
1366 guarantee(SystemDictionary::invoke_method_table() == NULL ||
1367 SystemDictionary::invoke_method_table()->number_of_entries() == 0,
1368 "invoke method table is not saved");
1369
1370 // At this point, many classes have been loaded.
1371 // Gather systemDictionary classes in a global array and do everything to
1372 // that so we don't have to walk the SystemDictionary again.
1373 _global_klass_objects = new GrowableArray<Klass*>(1000);
1374 CollectClassesClosure collect_classes;
1375 ClassLoaderDataGraph::loaded_classes_do(&collect_classes);
1376
1377 tty->print_cr("Number of classes %d", _global_klass_objects->length());
1378 {
1379 int num_type_array = 0, num_obj_array = 0, num_inst = 0;
1380 for (int i = 0; i < _global_klass_objects->length(); i++) {
1381 Klass* k = _global_klass_objects->at(i);
1382 if (k->is_instance_klass()) {
1383 num_inst ++;
1384 } else if (k->is_objArray_klass()) {
1385 num_obj_array ++;
1386 } else {
1387 assert(k->is_typeArray_klass(), "sanity");
1388 num_type_array ++;
1389 }
1390 }
1391 tty->print_cr(" instance classes = %5d", num_inst);
1392 tty->print_cr(" obj array classes = %5d", num_obj_array);
1393 tty->print_cr(" type array classes = %5d", num_type_array);
1394 }
1395
1396 // Ensure the ConstMethods won't be modified at run-time
1397 tty->print("Updating ConstMethods ... ");
1398 rewrite_nofast_bytecodes_and_calculate_fingerprints();
1399 tty->print_cr("done. ");
1400
1401 // Move classes from platform/system dictionaries into the boot dictionary
1402 SystemDictionary::combine_shared_dictionaries();
1403
1404 // Make sure all classes have a correct loader type.
1405 ClassLoaderData::the_null_class_loader_data()->dictionary()->classes_do(MetaspaceShared::check_shared_class_loader_type);
1406
1407 // Remove all references outside the metadata
1408 tty->print("Removing unshareable information ... ");
1409 remove_unshareable_in_classes();
1410 tty->print_cr("done. ");
1411
1412 // We don't support archiving unsafe anonymous classes. Verify that they are not stored in
1413 // any dictionaries.
1414 NOT_PRODUCT(assert_no_unsafe_anonymous_classes_in_dictionaries());
1415
1416 SystemDictionaryShared::finalize_verification_constraints();
1417
1418 ArchiveCompactor::initialize();
1419 ArchiveCompactor::copy_and_compact();
1420
1421 dump_symbols();
1422
1423 // Dump supported java heap objects
1424 _closed_archive_heap_regions = NULL;
1425 _open_archive_heap_regions = NULL;
1426 dump_java_heap_objects();
1427
1428 ArchiveCompactor::relocate_well_known_klasses();
1429
1430 char* read_only_tables_start = dump_read_only_tables();
1431 _ro_region.pack(&_md_region);
1432
1433 char* vtbl_list = _md_region.top();
1434 MetaspaceShared::allocate_cpp_vtable_clones();
1435 _md_region.pack(&_od_region);
1436
1437 // Relocate the archived class file data into the od region
1438 relocate_cached_class_file();
1439 _od_region.pack();
1440
1441 // The 5 core spaces are allocated consecutively mc->rw->ro->md->od, so there total size
1442 // is just the spaces between the two ends.
1443 size_t core_spaces_size = _od_region.end() - _mc_region.base();
1444 assert(core_spaces_size == (size_t)align_up(core_spaces_size, Metaspace::reserve_alignment()),
1445 "should already be aligned");
1446
1447 // During patching, some virtual methods may be called, so at this point
1448 // the vtables must contain valid methods (as filled in by CppVtableCloner::allocate).
1449 MetaspaceShared::patch_cpp_vtable_pointers();
1450
1451 // The vtable clones contain addresses of the current process.
1452 // We don't want to write these addresses into the archive.
1453 MetaspaceShared::zero_cpp_vtable_clones_for_writing();
1454
1455 // Create and write the archive file that maps the shared spaces.
1456
1457 FileMapInfo* mapinfo = new FileMapInfo();
1458 mapinfo->populate_header(os::vm_allocation_granularity());
1459 mapinfo->set_read_only_tables_start(read_only_tables_start);
1460 mapinfo->set_misc_data_patching_start(vtbl_list);
1461 mapinfo->set_cds_i2i_entry_code_buffers(MetaspaceShared::cds_i2i_entry_code_buffers());
1462 mapinfo->set_cds_i2i_entry_code_buffers_size(MetaspaceShared::cds_i2i_entry_code_buffers_size());
1463 mapinfo->set_core_spaces_size(core_spaces_size);
1464
1465 for (int pass=1; pass<=2; pass++) {
1466 if (pass == 1) {
1467 // The first pass doesn't actually write the data to disk. All it
1468 // does is to update the fields in the mapinfo->_header.
1469 } else {
1470 // After the first pass, the contents of mapinfo->_header are finalized,
1471 // so we can compute the header's CRC, and write the contents of the header
1472 // and the regions into disk.
1473 mapinfo->open_for_write();
1474 mapinfo->set_header_crc(mapinfo->compute_header_crc());
1475 }
1476 mapinfo->write_header();
1477
1478 // NOTE: md contains the trampoline code for method entries, which are patched at run time,
1479 // so it needs to be read/write.
1480 write_region(mapinfo, MetaspaceShared::mc, &_mc_region, /*read_only=*/false,/*allow_exec=*/true);
1481 write_region(mapinfo, MetaspaceShared::rw, &_rw_region, /*read_only=*/false,/*allow_exec=*/false);
1482 write_region(mapinfo, MetaspaceShared::ro, &_ro_region, /*read_only=*/true, /*allow_exec=*/false);
1483 write_region(mapinfo, MetaspaceShared::md, &_md_region, /*read_only=*/false,/*allow_exec=*/false);
1484 write_region(mapinfo, MetaspaceShared::od, &_od_region, /*read_only=*/true, /*allow_exec=*/false);
1485
1486 _total_string_region_size = mapinfo->write_archive_heap_regions(
1487 _closed_archive_heap_regions,
1488 _closed_archive_heap_oopmaps,
1489 MetaspaceShared::first_string,
1490 MetaspaceShared::max_strings);
1491 _total_open_archive_region_size = mapinfo->write_archive_heap_regions(
1492 _open_archive_heap_regions,
1493 _open_archive_heap_oopmaps,
1494 MetaspaceShared::first_open_archive_heap_region,
1495 MetaspaceShared::max_open_archive_heap_region);
1496 }
1497
1498 mapinfo->close();
1499
1500 // Restore the vtable in case we invoke any virtual methods.
1501 MetaspaceShared::clone_cpp_vtables((intptr_t*)vtbl_list);
1502
1503 print_region_stats();
1504
1505 if (log_is_enabled(Info, cds)) {
1506 ArchiveCompactor::alloc_stats()->print_stats(int(_ro_region.used()), int(_rw_region.used()),
1507 int(_mc_region.used()), int(_md_region.used()));
1508 }
1509
1510 if (PrintSystemDictionaryAtExit) {
1511 SystemDictionary::print();
1512 }
1513 // There may be other pending VM operations that operate on the InstanceKlasses,
1514 // which will fail because InstanceKlasses::remove_unshareable_info()
1515 // has been called. Forget these operations and exit the VM directly.
1516 vm_direct_exit(0);
1517 }
1518
1519 void VM_PopulateDumpSharedSpace::print_region_stats() {
1520 // Print statistics of all the regions
1521 const size_t total_reserved = _ro_region.reserved() + _rw_region.reserved() +
1522 _mc_region.reserved() + _md_region.reserved() +
1523 _od_region.reserved() +
1524 _total_string_region_size +
1525 _total_open_archive_region_size;
1526 const size_t total_bytes = _ro_region.used() + _rw_region.used() +
1527 _mc_region.used() + _md_region.used() +
1528 _od_region.used() +
1529 _total_string_region_size +
1530 _total_open_archive_region_size;
1531 const double total_u_perc = percent_of(total_bytes, total_reserved);
1532
1533 _mc_region.print(total_reserved);
1534 _rw_region.print(total_reserved);
1535 _ro_region.print(total_reserved);
1536 _md_region.print(total_reserved);
1537 _od_region.print(total_reserved);
1538 print_heap_region_stats(_closed_archive_heap_regions, "st", total_reserved);
1539 print_heap_region_stats(_open_archive_heap_regions, "oa", total_reserved);
1540
1541 tty->print_cr("total : " SIZE_FORMAT_W(9) " [100.0%% of total] out of " SIZE_FORMAT_W(9) " bytes [%5.1f%% used]",
1542 total_bytes, total_reserved, total_u_perc);
1543 }
1544
1545 void VM_PopulateDumpSharedSpace::print_heap_region_stats(GrowableArray<MemRegion> *heap_mem,
1546 const char *name, const size_t total_size) {
1547 int arr_len = heap_mem == NULL ? 0 : heap_mem->length();
1548 for (int i = 0; i < arr_len; i++) {
1549 char* start = (char*)heap_mem->at(i).start();
1550 size_t size = heap_mem->at(i).byte_size();
1551 char* top = start + size;
1552 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,
1553 name, i, size, size/double(total_size)*100.0, size, p2i(start));
1554
1555 }
1556 }
1557
1558 // Update a Java object to point its Klass* to the new location after
1559 // shared archive has been compacted.
1560 void MetaspaceShared::relocate_klass_ptr(oop o) {
1561 assert(DumpSharedSpaces, "sanity");
1562 Klass* k = ArchiveCompactor::get_relocated_klass(o->klass());
1563 o->set_klass(k);
1564 }
1565
1566 Klass* MetaspaceShared::get_relocated_klass(Klass *k) {
1567 assert(DumpSharedSpaces, "sanity");
1568 return ArchiveCompactor::get_relocated_klass(k);
1569 }
1570
1571 class LinkSharedClassesClosure : public KlassClosure {
1572 Thread* THREAD;
1573 bool _made_progress;
1574 public:
1575 LinkSharedClassesClosure(Thread* thread) : THREAD(thread), _made_progress(false) {}
1576
1577 void reset() { _made_progress = false; }
1578 bool made_progress() const { return _made_progress; }
1579
1580 void do_klass(Klass* k) {
1581 if (k->is_instance_klass()) {
1582 InstanceKlass* ik = InstanceKlass::cast(k);
1583 // Link the class to cause the bytecodes to be rewritten and the
1584 // cpcache to be created. Class verification is done according
1585 // to -Xverify setting.
1586 _made_progress |= MetaspaceShared::try_link_class(ik, THREAD);
1587 guarantee(!HAS_PENDING_EXCEPTION, "exception in link_class");
1588
1589 ik->constants()->resolve_class_constants(THREAD);
1590 }
1591 }
1592 };
1593
1594 class CheckSharedClassesClosure : public KlassClosure {
1595 bool _made_progress;
1596 public:
1597 CheckSharedClassesClosure() : _made_progress(false) {}
1598
1599 void reset() { _made_progress = false; }
1600 bool made_progress() const { return _made_progress; }
1601 void do_klass(Klass* k) {
1602 if (k->is_instance_klass() && InstanceKlass::cast(k)->check_sharing_error_state()) {
1603 _made_progress = true;
1604 }
1605 }
1606 };
1607
1608 void MetaspaceShared::check_shared_class_loader_type(InstanceKlass* ik) {
1609 ResourceMark rm;
1610 if (ik->shared_classpath_index() == UNREGISTERED_INDEX) {
1611 guarantee(ik->loader_type() == 0,
1612 "Class loader type must not be set for this class %s", ik->name()->as_C_string());
1613 } else {
1614 guarantee(ik->loader_type() != 0,
1615 "Class loader type must be set for this class %s", ik->name()->as_C_string());
1616 }
1617 }
1618
1619 void MetaspaceShared::link_and_cleanup_shared_classes(TRAPS) {
1620 // We need to iterate because verification may cause additional classes
1621 // to be loaded.
1622 LinkSharedClassesClosure link_closure(THREAD);
1623 do {
1624 link_closure.reset();
1625 ClassLoaderDataGraph::unlocked_loaded_classes_do(&link_closure);
1626 guarantee(!HAS_PENDING_EXCEPTION, "exception in link_class");
1627 } while (link_closure.made_progress());
1628
1629 if (_has_error_classes) {
1630 // Mark all classes whose super class or interfaces failed verification.
1631 CheckSharedClassesClosure check_closure;
1632 do {
1633 // Not completely sure if we need to do this iteratively. Anyway,
1634 // we should come here only if there are unverifiable classes, which
1635 // shouldn't happen in normal cases. So better safe than sorry.
1636 check_closure.reset();
1637 ClassLoaderDataGraph::unlocked_loaded_classes_do(&check_closure);
1638 } while (check_closure.made_progress());
1639
1640 if (IgnoreUnverifiableClassesDuringDump) {
1641 // This is useful when running JCK or SQE tests. You should not
1642 // enable this when running real apps.
1643 SystemDictionary::remove_classes_in_error_state();
1644 } else {
1645 tty->print_cr("Please remove the unverifiable classes from your class list and try again");
1646 exit(1);
1647 }
1648 }
1649 }
1650
1651 void MetaspaceShared::prepare_for_dumping() {
1652 Arguments::check_unsupported_dumping_properties();
1653 ClassLoader::initialize_shared_path();
1654 }
1655
1656 // Preload classes from a list, populate the shared spaces and dump to a
1657 // file.
1658 void MetaspaceShared::preload_and_dump(TRAPS) {
1659 { TraceTime timer("Dump Shared Spaces", TRACETIME_LOG(Info, startuptime));
1660 ResourceMark rm;
1661 char class_list_path_str[JVM_MAXPATHLEN];
1662 // Preload classes to be shared.
1663 // Should use some os:: method rather than fopen() here. aB.
1664 const char* class_list_path;
1665 if (SharedClassListFile == NULL) {
1666 // Construct the path to the class list (in jre/lib)
1667 // Walk up two directories from the location of the VM and
1668 // optionally tack on "lib" (depending on platform)
1669 os::jvm_path(class_list_path_str, sizeof(class_list_path_str));
1670 for (int i = 0; i < 3; i++) {
1671 char *end = strrchr(class_list_path_str, *os::file_separator());
1672 if (end != NULL) *end = '\0';
1673 }
1674 int class_list_path_len = (int)strlen(class_list_path_str);
1675 if (class_list_path_len >= 3) {
1676 if (strcmp(class_list_path_str + class_list_path_len - 3, "lib") != 0) {
1677 if (class_list_path_len < JVM_MAXPATHLEN - 4) {
1678 jio_snprintf(class_list_path_str + class_list_path_len,
1679 sizeof(class_list_path_str) - class_list_path_len,
1680 "%slib", os::file_separator());
1681 class_list_path_len += 4;
1682 }
1683 }
1684 }
1685 if (class_list_path_len < JVM_MAXPATHLEN - 10) {
1686 jio_snprintf(class_list_path_str + class_list_path_len,
1687 sizeof(class_list_path_str) - class_list_path_len,
1688 "%sclasslist", os::file_separator());
1689 }
1690 class_list_path = class_list_path_str;
1691 } else {
1692 class_list_path = SharedClassListFile;
1693 }
1694
1695 tty->print_cr("Loading classes to share ...");
1696 _has_error_classes = false;
1697 int class_count = preload_classes(class_list_path, THREAD);
1698 if (ExtraSharedClassListFile) {
1699 class_count += preload_classes(ExtraSharedClassListFile, THREAD);
1700 }
1701 tty->print_cr("Loading classes to share: done.");
1702
1703 log_info(cds)("Shared spaces: preloaded %d classes", class_count);
1704
1705 // Rewrite and link classes
1706 tty->print_cr("Rewriting and linking classes ...");
1707
1708 // Link any classes which got missed. This would happen if we have loaded classes that
1709 // were not explicitly specified in the classlist. E.g., if an interface implemented by class K
1710 // fails verification, all other interfaces that were not specified in the classlist but
1711 // are implemented by K are not verified.
1712 link_and_cleanup_shared_classes(CATCH);
1713 tty->print_cr("Rewriting and linking classes: done");
1714
1715 SystemDictionary::clear_invoke_method_table();
1716 HeapShared::init_archivable_static_fields(THREAD);
1717
1718 VM_PopulateDumpSharedSpace op;
1719 VMThread::execute(&op);
1720 }
1721 }
1722
1723
1724 int MetaspaceShared::preload_classes(const char* class_list_path, TRAPS) {
1725 ClassListParser parser(class_list_path);
1726 int class_count = 0;
1727
1728 while (parser.parse_one_line()) {
1729 Klass* klass = ClassLoaderExt::load_one_class(&parser, THREAD);
1730 if (HAS_PENDING_EXCEPTION) {
1731 if (klass == NULL &&
1732 (PENDING_EXCEPTION->klass()->name() == vmSymbols::java_lang_ClassNotFoundException())) {
1733 // print a warning only when the pending exception is class not found
1734 tty->print_cr("Preload Warning: Cannot find %s", parser.current_class_name());
1735 }
1736 CLEAR_PENDING_EXCEPTION;
1737 }
1738 if (klass != NULL) {
1739 if (log_is_enabled(Trace, cds)) {
1740 ResourceMark rm;
1741 log_trace(cds)("Shared spaces preloaded: %s", klass->external_name());
1742 }
1743
1744 if (klass->is_instance_klass()) {
1745 InstanceKlass* ik = InstanceKlass::cast(klass);
1746
1747 // Link the class to cause the bytecodes to be rewritten and the
1748 // cpcache to be created. The linking is done as soon as classes
1749 // are loaded in order that the related data structures (klass and
1750 // cpCache) are located together.
1751 try_link_class(ik, THREAD);
1752 guarantee(!HAS_PENDING_EXCEPTION, "exception in link_class");
1753 }
1754
1755 class_count++;
1756 }
1757 }
1758
1759 return class_count;
1760 }
1761
1762 // Returns true if the class's status has changed
1763 bool MetaspaceShared::try_link_class(InstanceKlass* ik, TRAPS) {
1764 assert(DumpSharedSpaces, "should only be called during dumping");
1765 if (ik->init_state() < InstanceKlass::linked) {
1766 bool saved = BytecodeVerificationLocal;
1767 if (ik->loader_type() == 0 && ik->class_loader() == NULL) {
1768 // The verification decision is based on BytecodeVerificationRemote
1769 // for non-system classes. Since we are using the NULL classloader
1770 // to load non-system classes for customized class loaders during dumping,
1771 // we need to temporarily change BytecodeVerificationLocal to be the same as
1772 // BytecodeVerificationRemote. Note this can cause the parent system
1773 // classes also being verified. The extra overhead is acceptable during
1774 // dumping.
1775 BytecodeVerificationLocal = BytecodeVerificationRemote;
1776 }
1777 ik->link_class(THREAD);
1778 if (HAS_PENDING_EXCEPTION) {
1779 ResourceMark rm;
1780 tty->print_cr("Preload Warning: Verification failed for %s",
1781 ik->external_name());
1782 CLEAR_PENDING_EXCEPTION;
1783 ik->set_in_error_state();
1784 _has_error_classes = true;
1785 }
1786 BytecodeVerificationLocal = saved;
1787 return true;
1788 } else {
1789 return false;
1790 }
1791 }
1792
1793 #if INCLUDE_CDS_JAVA_HEAP
1794 void VM_PopulateDumpSharedSpace::dump_java_heap_objects() {
1795 // The closed and open archive heap space has maximum two regions.
1796 // See FileMapInfo::write_archive_heap_regions() for details.
1797 _closed_archive_heap_regions = new GrowableArray<MemRegion>(2);
1798 _open_archive_heap_regions = new GrowableArray<MemRegion>(2);
1799 HeapShared::archive_java_heap_objects(_closed_archive_heap_regions,
1800 _open_archive_heap_regions);
1801 }
1802
1803 void VM_PopulateDumpSharedSpace::dump_archive_heap_oopmaps() {
1804 if (HeapShared::is_heap_object_archiving_allowed()) {
1805 _closed_archive_heap_oopmaps = new GrowableArray<ArchiveHeapOopmapInfo>(2);
1806 dump_archive_heap_oopmaps(_closed_archive_heap_regions, _closed_archive_heap_oopmaps);
1807
1808 _open_archive_heap_oopmaps = new GrowableArray<ArchiveHeapOopmapInfo>(2);
1809 dump_archive_heap_oopmaps(_open_archive_heap_regions, _open_archive_heap_oopmaps);
1810 }
1811 }
1812
1813 void VM_PopulateDumpSharedSpace::dump_archive_heap_oopmaps(GrowableArray<MemRegion>* regions,
1814 GrowableArray<ArchiveHeapOopmapInfo>* oopmaps) {
1815 for (int i=0; i<regions->length(); i++) {
1816 ResourceBitMap oopmap = HeapShared::calculate_oopmap(regions->at(i));
1817 size_t size_in_bits = oopmap.size();
1818 size_t size_in_bytes = oopmap.size_in_bytes();
1819 uintptr_t* buffer = (uintptr_t*)_ro_region.allocate(size_in_bytes, sizeof(intptr_t));
1820 oopmap.write_to(buffer, size_in_bytes);
1821 log_info(cds)("Oopmap = " INTPTR_FORMAT " (" SIZE_FORMAT_W(6) " bytes) for heap region "
1822 INTPTR_FORMAT " (" SIZE_FORMAT_W(8) " bytes)",
1823 p2i(buffer), size_in_bytes,
1824 p2i(regions->at(i).start()), regions->at(i).byte_size());
1825
1826 ArchiveHeapOopmapInfo info;
1827 info._oopmap = (address)buffer;
1828 info._oopmap_size_in_bits = size_in_bits;
1829 oopmaps->append(info);
1830 }
1831 }
1832 #endif // INCLUDE_CDS_JAVA_HEAP
1833
1834 // Closure for serializing initialization data in from a data area
1835 // (ptr_array) read from the shared file.
1836
1837 class ReadClosure : public SerializeClosure {
1838 private:
1839 intptr_t** _ptr_array;
1840
1841 inline intptr_t nextPtr() {
1842 return *(*_ptr_array)++;
1843 }
1844
1845 public:
1846 ReadClosure(intptr_t** ptr_array) { _ptr_array = ptr_array; }
1847
1848 void do_ptr(void** p) {
1849 assert(*p == NULL, "initializing previous initialized pointer.");
1850 intptr_t obj = nextPtr();
1851 assert((intptr_t)obj >= 0 || (intptr_t)obj < -100,
1852 "hit tag while initializing ptrs.");
1853 *p = (void*)obj;
1854 }
1855
1856 void do_u4(u4* p) {
1857 intptr_t obj = nextPtr();
1858 *p = (u4)(uintx(obj));
1859 }
1860
1861 void do_tag(int tag) {
1862 int old_tag;
1863 old_tag = (int)(intptr_t)nextPtr();
1864 // do_int(&old_tag);
1865 assert(tag == old_tag, "old tag doesn't match");
1866 FileMapInfo::assert_mark(tag == old_tag);
1867 }
1868
1869 void do_oop(oop *p) {
1870 narrowOop o = (narrowOop)nextPtr();
1871 if (o == 0 || !HeapShared::open_archive_heap_region_mapped()) {
1872 p = NULL;
1873 } else {
1874 assert(HeapShared::is_heap_object_archiving_allowed(),
1875 "Archived heap object is not allowed");
1876 assert(HeapShared::open_archive_heap_region_mapped(),
1877 "Open archive heap region is not mapped");
1878 *p = HeapShared::decode_from_archive(o);
1879 }
1880 }
1881
1882 void do_region(u_char* start, size_t size) {
1883 assert((intptr_t)start % sizeof(intptr_t) == 0, "bad alignment");
1884 assert(size % sizeof(intptr_t) == 0, "bad size");
1885 do_tag((int)size);
1886 while (size > 0) {
1887 *(intptr_t*)start = nextPtr();
1888 start += sizeof(intptr_t);
1889 size -= sizeof(intptr_t);
1890 }
1891 }
1892
1893 bool reading() const { return true; }
1894 };
1895
1896 // Return true if given address is in the misc data region
1897 bool MetaspaceShared::is_in_shared_region(const void* p, int idx) {
1898 return UseSharedSpaces && FileMapInfo::current_info()->is_in_shared_region(p, idx);
1899 }
1900
1901 bool MetaspaceShared::is_in_trampoline_frame(address addr) {
1902 if (UseSharedSpaces && is_in_shared_region(addr, MetaspaceShared::mc)) {
1903 return true;
1904 }
1905 return false;
1906 }
1907
1908 // Map shared spaces at requested addresses and return if succeeded.
1909 bool MetaspaceShared::map_shared_spaces(FileMapInfo* mapinfo) {
1910 size_t image_alignment = mapinfo->alignment();
1911
1912 #ifndef _WINDOWS
1913 // Map in the shared memory and then map the regions on top of it.
1914 // On Windows, don't map the memory here because it will cause the
1915 // mappings of the regions to fail.
1916 ReservedSpace shared_rs = mapinfo->reserve_shared_memory();
1917 if (!shared_rs.is_reserved()) return false;
1918 #endif
1919
1920 assert(!DumpSharedSpaces, "Should not be called with DumpSharedSpaces");
1921
1922 char* ro_base = NULL; char* ro_top;
1923 char* rw_base = NULL; char* rw_top;
1924 char* mc_base = NULL; char* mc_top;
1925 char* md_base = NULL; char* md_top;
1926 char* od_base = NULL; char* od_top;
1927
1928 // Map each shared region
1929 if ((mc_base = mapinfo->map_region(mc, &mc_top)) != NULL &&
1930 (rw_base = mapinfo->map_region(rw, &rw_top)) != NULL &&
1931 (ro_base = mapinfo->map_region(ro, &ro_top)) != NULL &&
1932 (md_base = mapinfo->map_region(md, &md_top)) != NULL &&
1933 (od_base = mapinfo->map_region(od, &od_top)) != NULL &&
1934 (image_alignment == (size_t)os::vm_allocation_granularity()) &&
1935 mapinfo->validate_shared_path_table()) {
1936 // Success -- set up MetaspaceObj::_shared_metaspace_{base,top} for
1937 // fast checking in MetaspaceShared::is_in_shared_metaspace() and
1938 // MetaspaceObj::is_shared().
1939 //
1940 // We require that mc->rw->ro->md->od to be laid out consecutively, with no
1941 // gaps between them. That way, we can ensure that the OS won't be able to
1942 // allocate any new memory spaces inside _shared_metaspace_{base,top}, which
1943 // would mess up the simple comparision in MetaspaceShared::is_in_shared_metaspace().
1944 assert(mc_base < ro_base && mc_base < rw_base && mc_base < md_base && mc_base < od_base, "must be");
1945 assert(od_top > ro_top && od_top > rw_top && od_top > md_top && od_top > mc_top , "must be");
1946 assert(mc_top == rw_base, "must be");
1947 assert(rw_top == ro_base, "must be");
1948 assert(ro_top == md_base, "must be");
1949 assert(md_top == od_base, "must be");
1950
1951 MetaspaceObj::_shared_metaspace_base = (void*)mc_base;
1952 MetaspaceObj::_shared_metaspace_top = (void*)od_top;
1953 return true;
1954 } else {
1955 // If there was a failure in mapping any of the spaces, unmap the ones
1956 // that succeeded
1957 if (ro_base != NULL) mapinfo->unmap_region(ro);
1958 if (rw_base != NULL) mapinfo->unmap_region(rw);
1959 if (mc_base != NULL) mapinfo->unmap_region(mc);
1960 if (md_base != NULL) mapinfo->unmap_region(md);
1961 if (od_base != NULL) mapinfo->unmap_region(od);
1962 #ifndef _WINDOWS
1963 // Release the entire mapped region
1964 shared_rs.release();
1965 #endif
1966 // If -Xshare:on is specified, print out the error message and exit VM,
1967 // otherwise, set UseSharedSpaces to false and continue.
1968 if (RequireSharedSpaces || PrintSharedArchiveAndExit) {
1969 vm_exit_during_initialization("Unable to use shared archive.", "Failed map_region for using -Xshare:on.");
1970 } else {
1971 FLAG_SET_DEFAULT(UseSharedSpaces, false);
1972 }
1973 return false;
1974 }
1975 }
1976
1977 // Read the miscellaneous data from the shared file, and
1978 // serialize it out to its various destinations.
1979
1980 void MetaspaceShared::initialize_shared_spaces() {
1981 FileMapInfo *mapinfo = FileMapInfo::current_info();
1982 _cds_i2i_entry_code_buffers = mapinfo->cds_i2i_entry_code_buffers();
1983 _cds_i2i_entry_code_buffers_size = mapinfo->cds_i2i_entry_code_buffers_size();
1984 _core_spaces_size = mapinfo->core_spaces_size();
1985 char* buffer = mapinfo->misc_data_patching_start();
1986 clone_cpp_vtables((intptr_t*)buffer);
1987
1988 // The rest of the data is now stored in the RW region
1989 buffer = mapinfo->read_only_tables_start();
1990 int sharedDictionaryLen = *(intptr_t*)buffer;
1991 buffer += sizeof(intptr_t);
1992 int number_of_entries = *(intptr_t*)buffer;
1993 buffer += sizeof(intptr_t);
1994 SystemDictionary::set_shared_dictionary((HashtableBucket<mtClass>*)buffer,
1995 sharedDictionaryLen,
1996 number_of_entries);
1997 buffer += sharedDictionaryLen;
1998
1999 // The following data are the linked list elements
2000 // (HashtableEntry objects) for the shared dictionary table.
2001
2002 int len = *(intptr_t*)buffer; // skip over shared dictionary entries
2003 buffer += sizeof(intptr_t);
2004 buffer += len;
2005
2006 // The table of archived java heap object sub-graph infos
2007 buffer = HeapShared::read_archived_subgraph_infos(buffer);
2008
2009 // Verify various attributes of the archive, plus initialize the
2010 // shared string/symbol tables
2011 intptr_t* array = (intptr_t*)buffer;
2012 ReadClosure rc(&array);
2013 serialize(&rc);
2014
2015 // Initialize the run-time symbol table.
2016 SymbolTable::create_table();
2017
2018 mapinfo->patch_archived_heap_embedded_pointers();
2019
2020 // Close the mapinfo file
2021 mapinfo->close();
2022
2023 if (PrintSharedArchiveAndExit) {
2024 if (PrintSharedDictionary) {
2025 tty->print_cr("\nShared classes:\n");
2026 SystemDictionary::print_shared(tty);
2027 }
2028 if (_archive_loading_failed) {
2029 tty->print_cr("archive is invalid");
2030 vm_exit(1);
2031 } else {
2032 tty->print_cr("archive is valid");
2033 vm_exit(0);
2034 }
2035 }
2036 }
2037
2038 // JVM/TI RedefineClasses() support:
2039 bool MetaspaceShared::remap_shared_readonly_as_readwrite() {
2040 assert(SafepointSynchronize::is_at_safepoint(), "must be at safepoint");
2041
2042 if (UseSharedSpaces) {
2043 // remap the shared readonly space to shared readwrite, private
2044 FileMapInfo* mapinfo = FileMapInfo::current_info();
2045 if (!mapinfo->remap_shared_readonly_as_readwrite()) {
2046 return false;
2047 }
2048 _remapped_readwrite = true;
2049 }
2050 return true;
2051 }
2052
2053 void MetaspaceShared::report_out_of_space(const char* name, size_t needed_bytes) {
2054 // This is highly unlikely to happen on 64-bits because we have reserved a 4GB space.
2055 // On 32-bit we reserve only 256MB so you could run out of space with 100,000 classes
2056 // or so.
2057 _mc_region.print_out_of_space_msg(name, needed_bytes);
2058 _rw_region.print_out_of_space_msg(name, needed_bytes);
2059 _ro_region.print_out_of_space_msg(name, needed_bytes);
2060 _md_region.print_out_of_space_msg(name, needed_bytes);
2061 _od_region.print_out_of_space_msg(name, needed_bytes);
2062
2063 vm_exit_during_initialization(err_msg("Unable to allocate from '%s' region", name),
2064 "Please reduce the number of shared classes.");
2065 }