1 /*
2 * Copyright (c) 2012, 2019, 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/javaClasses.inline.hpp"
33 #include "classfile/placeholders.hpp"
34 #include "classfile/symbolTable.hpp"
35 #include "classfile/stringTable.hpp"
36 #include "classfile/systemDictionary.hpp"
37 #include "classfile/systemDictionaryShared.hpp"
38 #include "code/codeCache.hpp"
39 #include "gc/shared/softRefPolicy.hpp"
40 #include "interpreter/bytecodeStream.hpp"
41 #include "interpreter/bytecodes.hpp"
42 #include "logging/log.hpp"
43 #include "logging/logMessage.hpp"
44 #include "memory/filemap.hpp"
45 #include "memory/heapShared.inline.hpp"
46 #include "memory/metaspace.hpp"
47 #include "memory/metaspaceClosure.hpp"
48 #include "memory/metaspaceShared.hpp"
49 #include "memory/resourceArea.hpp"
50 #include "memory/universe.hpp"
51 #include "memory/dynamicArchive.hpp"
52 #include "oops/compressedOops.inline.hpp"
53 #include "oops/instanceClassLoaderKlass.hpp"
54 #include "oops/instanceMirrorKlass.hpp"
55 #include "oops/instanceRefKlass.hpp"
56 #include "oops/methodData.hpp"
57 #include "oops/objArrayKlass.hpp"
58 #include "oops/objArrayOop.hpp"
59 #include "oops/oop.inline.hpp"
60 #include "oops/typeArrayKlass.hpp"
61 #include "prims/jvmtiRedefineClasses.hpp"
62 #include "runtime/handles.inline.hpp"
63 #include "runtime/os.hpp"
64 #include "runtime/safepointVerifiers.hpp"
65 #include "runtime/signature.hpp"
66 #include "runtime/timerTrace.hpp"
67 #include "runtime/vmThread.hpp"
68 #include "runtime/vmOperations.hpp"
69 #include "utilities/align.hpp"
70 #include "utilities/bitMap.hpp"
71 #include "utilities/defaultStream.hpp"
72 #include "utilities/hashtable.inline.hpp"
73 #if INCLUDE_G1GC
74 #include "gc/g1/g1CollectedHeap.hpp"
75 #endif
76
77 ReservedSpace MetaspaceShared::_shared_rs;
78 VirtualSpace MetaspaceShared::_shared_vs;
79 MetaspaceSharedStats MetaspaceShared::_stats;
80 bool MetaspaceShared::_has_error_classes;
81 bool MetaspaceShared::_archive_loading_failed = false;
82 bool MetaspaceShared::_remapped_readwrite = false;
83 address MetaspaceShared::_i2i_entry_code_buffers = NULL;
84 size_t MetaspaceShared::_i2i_entry_code_buffers_size = 0;
85 size_t MetaspaceShared::_core_spaces_size = 0;
86 void* MetaspaceShared::_shared_metaspace_static_top = NULL;
87
88 // The CDS archive is divided into the following regions:
89 // mc - misc code (the method entry trampolines)
90 // rw - read-write metadata
91 // ro - read-only metadata and read-only tables
92 // md - misc data (the c++ vtables)
93 //
94 // ca0 - closed archive heap space #0
95 // ca1 - closed archive heap space #1 (may be empty)
96 // oa0 - open archive heap space #0
97 // oa1 - open archive heap space #1 (may be empty)
98 //
99 // The mc, rw, ro, and md regions are linearly allocated, starting from
100 // SharedBaseAddress, in the order of mc->rw->ro->md. The size of these 4 regions
101 // are page-aligned, and there's no gap between any consecutive regions.
102 //
103 // These 4 regions are populated in the following steps:
104 // [1] All classes are loaded in MetaspaceShared::preload_classes(). All metadata are
105 // temporarily allocated outside of the shared regions. Only the method entry
106 // trampolines are written into the mc region.
107 // [2] ArchiveCompactor copies RW metadata into the rw region.
108 // [3] ArchiveCompactor copies RO metadata into the ro region.
109 // [4] SymbolTable, StringTable, SystemDictionary, and a few other read-only data
110 // are copied into the ro region as read-only tables.
111 // [5] C++ vtables are copied into the md region.
112 //
113 // The s0/s1 and oa0/oa1 regions are populated inside HeapShared::archive_java_heap_objects.
114 // Their layout is independent of the other 4 regions.
115
116 char* DumpRegion::expand_top_to(char* newtop) {
117 assert(is_allocatable(), "must be initialized and not packed");
118 assert(newtop >= _top, "must not grow backwards");
119 if (newtop > _end) {
120 MetaspaceShared::report_out_of_space(_name, newtop - _top);
121 ShouldNotReachHere();
122 }
123 uintx delta;
124 if (DynamicDumpSharedSpaces) {
125 delta = DynamicArchive::object_delta_uintx(newtop);
126 } else {
127 delta = MetaspaceShared::object_delta_uintx(newtop);
128 }
129 if (delta > MAX_SHARED_DELTA) {
130 // This is just a sanity check and should not appear in any real world usage. This
131 // happens only if you allocate more than 2GB of shared objects and would require
132 // millions of shared classes.
133 vm_exit_during_initialization("Out of memory in the CDS archive",
134 "Please reduce the number of shared classes.");
135 }
136
137 MetaspaceShared::commit_shared_space_to(newtop);
138 _top = newtop;
139 return _top;
140 }
141
142 char* DumpRegion::allocate(size_t num_bytes, size_t alignment) {
143 char* p = (char*)align_up(_top, alignment);
144 char* newtop = p + align_up(num_bytes, alignment);
145 expand_top_to(newtop);
146 memset(p, 0, newtop - p);
147 return p;
148 }
149
150 void DumpRegion::print(size_t total_bytes) const {
151 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,
152 _name, used(), percent_of(used(), total_bytes), reserved(), percent_of(used(), reserved()), p2i(_base));
153 }
154
155 void DumpRegion::print_out_of_space_msg(const char* failing_region, size_t needed_bytes) {
156 tty->print("[%-8s] " PTR_FORMAT " - " PTR_FORMAT " capacity =%9d, allocated =%9d",
157 _name, p2i(_base), p2i(_top), int(_end - _base), int(_top - _base));
158 if (strcmp(_name, failing_region) == 0) {
159 tty->print_cr(" required = %d", int(needed_bytes));
160 } else {
161 tty->cr();
162 }
163 }
164
165 void DumpRegion::pack(DumpRegion* next) {
166 assert(!is_packed(), "sanity");
167 _end = (char*)align_up(_top, Metaspace::reserve_alignment());
168 _is_packed = true;
169 if (next != NULL) {
170 next->_base = next->_top = this->_end;
171 next->_end = MetaspaceShared::shared_rs()->end();
172 }
173 }
174
175 DumpRegion _mc_region("mc"), _ro_region("ro"), _rw_region("rw"), _md_region("md");
176 size_t _total_closed_archive_region_size = 0, _total_open_archive_region_size = 0;
177
178 void MetaspaceShared::init_shared_dump_space(DumpRegion* first_space, address first_space_bottom) {
179 // Start with 0 committed bytes. The memory will be committed as needed by
180 // MetaspaceShared::commit_shared_space_to().
181 if (!_shared_vs.initialize(_shared_rs, 0)) {
182 vm_exit_during_initialization("Unable to allocate memory for shared space");
183 }
184 first_space->init(&_shared_rs, (char*)first_space_bottom);
185 }
186
187 DumpRegion* MetaspaceShared::misc_code_dump_space() {
188 return &_mc_region;
189 }
190
191 DumpRegion* MetaspaceShared::read_write_dump_space() {
192 return &_rw_region;
193 }
194
195 DumpRegion* MetaspaceShared::read_only_dump_space() {
196 return &_ro_region;
197 }
198
199 void MetaspaceShared::pack_dump_space(DumpRegion* current, DumpRegion* next,
200 ReservedSpace* rs) {
201 current->pack(next);
202 }
203
204 char* MetaspaceShared::misc_code_space_alloc(size_t num_bytes) {
205 return _mc_region.allocate(num_bytes);
206 }
207
208 char* MetaspaceShared::read_only_space_alloc(size_t num_bytes) {
209 return _ro_region.allocate(num_bytes);
210 }
211
212 void MetaspaceShared::initialize_runtime_shared_and_meta_spaces() {
213 assert(UseSharedSpaces, "Must be called when UseSharedSpaces is enabled");
214
215 // If using shared space, open the file that contains the shared space
216 // and map in the memory before initializing the rest of metaspace (so
217 // the addresses don't conflict)
218 FileMapInfo* mapinfo = new FileMapInfo(true);
219
220 // Open the shared archive file, read and validate the header. If
221 // initialization fails, shared spaces [UseSharedSpaces] are
222 // disabled and the file is closed.
223 // Map in spaces now also
224 if (mapinfo->initialize(true) && map_shared_spaces(mapinfo)) {
225 size_t cds_total = core_spaces_size();
226 address cds_address = (address)mapinfo->region_addr(0);
227 char* cds_end = (char *)align_up(cds_address + cds_total,
228 Metaspace::reserve_alignment());
229
230 // Mapping the dynamic archive before allocating the class space
231 cds_end = initialize_dynamic_runtime_shared_spaces((char*)cds_address, cds_end);
232
233 #ifdef _LP64
234 if (Metaspace::using_class_space()) {
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 CompressedKlassPointers::set_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 char* MetaspaceShared::initialize_dynamic_runtime_shared_spaces(
251 char* static_start, char* static_end) {
252 assert(UseSharedSpaces, "must be runtime");
253 char* cds_end = static_end;
254 if (!DynamicDumpSharedSpaces) {
255 address dynamic_top = DynamicArchive::map();
256 if (dynamic_top != NULL) {
257 assert(dynamic_top > (address)static_start, "Unexpected layout");
258 MetaspaceObj::expand_shared_metaspace_range(dynamic_top);
259 cds_end = (char *)align_up(dynamic_top, Metaspace::reserve_alignment());
260 }
261 }
262 return cds_end;
263 }
264
265 ReservedSpace* MetaspaceShared::reserve_shared_rs(size_t size, size_t alignment,
266 bool large, char* requested_address) {
267 if (requested_address != NULL) {
268 _shared_rs = ReservedSpace(size, alignment, large, requested_address);
269 } else {
270 _shared_rs = ReservedSpace(size, alignment, large);
271 }
272 return &_shared_rs;
273 }
274
275 void MetaspaceShared::initialize_dumptime_shared_and_meta_spaces() {
276 assert(DumpSharedSpaces, "should be called for dump time only");
277 const size_t reserve_alignment = Metaspace::reserve_alignment();
278 bool large_pages = false; // No large pages when dumping the CDS archive.
279 char* shared_base = (char*)align_up((char*)SharedBaseAddress, reserve_alignment);
280
281 #ifdef _LP64
282 // On 64-bit VM, the heap and class space layout will be the same as if
283 // you're running in -Xshare:on mode:
284 //
285 // +-- SharedBaseAddress (default = 0x800000000)
286 // v
287 // +-..---------+---------+ ... +----+----+----+----+---------------+
288 // | Heap | Archive | | MC | RW | RO | MD | class space |
289 // +-..---------+---------+ ... +----+----+----+----+---------------+
290 // |<-- MaxHeapSize -->| |<-- UnscaledClassSpaceMax = 4GB -->|
291 //
292 const uint64_t UnscaledClassSpaceMax = (uint64_t(max_juint) + 1);
293 const size_t cds_total = align_down(UnscaledClassSpaceMax, reserve_alignment);
294 #else
295 // We don't support archives larger than 256MB on 32-bit due to limited virtual address space.
296 size_t cds_total = align_down(256*M, reserve_alignment);
297 #endif
298
299 // First try to reserve the space at the specified SharedBaseAddress.
300 //_shared_rs = ReservedSpace(cds_total, reserve_alignment, large_pages, shared_base);
301 reserve_shared_rs(cds_total, reserve_alignment, large_pages, shared_base);
302 if (_shared_rs.is_reserved()) {
303 assert(shared_base == 0 || _shared_rs.base() == shared_base, "should match");
304 } else {
305 // Get a mmap region anywhere if the SharedBaseAddress fails.
306 //_shared_rs = ReservedSpace(cds_total, reserve_alignment, large_pages);
307 reserve_shared_rs(cds_total, reserve_alignment, large_pages, NULL);
308 }
309 if (!_shared_rs.is_reserved()) {
310 vm_exit_during_initialization("Unable to reserve memory for shared space",
311 err_msg(SIZE_FORMAT " bytes.", cds_total));
312 }
313
314 #ifdef _LP64
315 // During dump time, we allocate 4GB (UnscaledClassSpaceMax) of space and split it up:
316 // + The upper 1 GB is used as the "temporary compressed class space" -- preload_classes()
317 // will store Klasses into this space.
318 // + The lower 3 GB is used for the archive -- when preload_classes() is done,
319 // ArchiveCompactor will copy the class metadata into this space, first the RW parts,
320 // then the RO parts.
321
322 assert(UseCompressedOops && UseCompressedClassPointers,
323 "UseCompressedOops and UseCompressedClassPointers must be set");
324
325 size_t max_archive_size = align_down(cds_total * 3 / 4, reserve_alignment);
326 ReservedSpace tmp_class_space = _shared_rs.last_part(max_archive_size);
327 CompressedClassSpaceSize = align_down(tmp_class_space.size(), reserve_alignment);
328 _shared_rs = _shared_rs.first_part(max_archive_size);
329
330 // Set up compress class pointers.
331 CompressedKlassPointers::set_base((address)_shared_rs.base());
332 // Set narrow_klass_shift to be LogKlassAlignmentInBytes. This is consistent
333 // with AOT.
334 CompressedKlassPointers::set_shift(LogKlassAlignmentInBytes);
335 // Set the range of klass addresses to 4GB.
336 CompressedKlassPointers::set_range(cds_total);
337
338 Metaspace::initialize_class_space(tmp_class_space);
339 log_info(cds)("narrow_klass_base = " PTR_FORMAT ", narrow_klass_shift = %d",
340 p2i(CompressedKlassPointers::base()), CompressedKlassPointers::shift());
341
342 log_info(cds)("Allocated temporary class space: " SIZE_FORMAT " bytes at " PTR_FORMAT,
343 CompressedClassSpaceSize, p2i(tmp_class_space.base()));
344 #endif
345
346 init_shared_dump_space(&_mc_region);
347 SharedBaseAddress = (size_t)_shared_rs.base();
348 tty->print_cr("Allocated shared space: " SIZE_FORMAT " bytes at " PTR_FORMAT,
349 _shared_rs.size(), p2i(_shared_rs.base()));
350 }
351
352 // Called by universe_post_init()
353 void MetaspaceShared::post_initialize(TRAPS) {
354 if (UseSharedSpaces) {
355 int size = FileMapInfo::get_number_of_shared_paths();
356 if (size > 0) {
357 SystemDictionaryShared::allocate_shared_data_arrays(size, THREAD);
358 if (!DynamicDumpSharedSpaces) {
359 FileMapInfo* info;
360 if (FileMapInfo::dynamic_info() == NULL) {
361 info = FileMapInfo::current_info();
362 } else {
363 info = FileMapInfo::dynamic_info();
364 }
365 ClassLoaderExt::init_paths_start_index(info->app_class_paths_start_index());
366 ClassLoaderExt::init_app_module_paths_start_index(info->app_module_paths_start_index());
367 }
368 }
369 }
370 }
371
372 static GrowableArray<Handle>* _extra_interned_strings = NULL;
373
374 void MetaspaceShared::read_extra_data(const char* filename, TRAPS) {
375 _extra_interned_strings = new (ResourceObj::C_HEAP, mtInternal)GrowableArray<Handle>(10000, true);
376
377 HashtableTextDump reader(filename);
378 reader.check_version("VERSION: 1.0");
379
380 while (reader.remain() > 0) {
381 int utf8_length;
382 int prefix_type = reader.scan_prefix(&utf8_length);
383 ResourceMark rm(THREAD);
384 if (utf8_length == 0x7fffffff) {
385 // buf_len will overflown 32-bit value.
386 vm_exit_during_initialization(err_msg("string length too large: %d", utf8_length));
387 }
388 int buf_len = utf8_length+1;
389 char* utf8_buffer = NEW_RESOURCE_ARRAY(char, buf_len);
390 reader.get_utf8(utf8_buffer, utf8_length);
391 utf8_buffer[utf8_length] = '\0';
392
393 if (prefix_type == HashtableTextDump::SymbolPrefix) {
394 SymbolTable::new_permanent_symbol(utf8_buffer);
395 } else{
396 assert(prefix_type == HashtableTextDump::StringPrefix, "Sanity");
397 oop s = StringTable::intern(utf8_buffer, THREAD);
398
399 if (HAS_PENDING_EXCEPTION) {
400 log_warning(cds, heap)("[line %d] extra interned string allocation failed; size too large: %d",
401 reader.last_line_no(), utf8_length);
402 CLEAR_PENDING_EXCEPTION;
403 } else {
404 #if INCLUDE_G1GC
405 if (UseG1GC) {
406 typeArrayOop body = java_lang_String::value(s);
407 const HeapRegion* hr = G1CollectedHeap::heap()->heap_region_containing(body);
408 if (hr->is_humongous()) {
409 // Don't keep it alive, so it will be GC'ed before we dump the strings, in order
410 // to maximize free heap space and minimize fragmentation.
411 log_warning(cds, heap)("[line %d] extra interned string ignored; size too large: %d",
412 reader.last_line_no(), utf8_length);
413 continue;
414 }
415 }
416 #endif
417 // Interned strings are GC'ed if there are no references to it, so let's
418 // add a reference to keep this string alive.
419 assert(s != NULL, "must succeed");
420 Handle h(THREAD, s);
421 _extra_interned_strings->append(h);
422 }
423 }
424 }
425 }
426
427 void MetaspaceShared::commit_shared_space_to(char* newtop) {
428 Arguments::assert_is_dumping_archive();
429 char* base = _shared_rs.base();
430 size_t need_committed_size = newtop - base;
431 size_t has_committed_size = _shared_vs.committed_size();
432 if (need_committed_size < has_committed_size) {
433 return;
434 }
435
436 size_t min_bytes = need_committed_size - has_committed_size;
437 size_t preferred_bytes = 1 * M;
438 size_t uncommitted = _shared_vs.reserved_size() - has_committed_size;
439
440 size_t commit =MAX2(min_bytes, preferred_bytes);
441 commit = MIN2(commit, uncommitted);
442 assert(commit <= uncommitted, "sanity");
443
444 bool result = _shared_vs.expand_by(commit, false);
445 if (!result) {
446 vm_exit_during_initialization(err_msg("Failed to expand shared space to " SIZE_FORMAT " bytes",
447 need_committed_size));
448 }
449
450 log_info(cds)("Expanding shared spaces by " SIZE_FORMAT_W(7) " bytes [total " SIZE_FORMAT_W(9) " bytes ending at %p]",
451 commit, _shared_vs.actual_committed_size(), _shared_vs.high());
452 }
453
454 // Read/write a data stream for restoring/preserving metadata pointers and
455 // miscellaneous data from/to the shared archive file.
456
457 void MetaspaceShared::serialize(SerializeClosure* soc) {
458 int tag = 0;
459 soc->do_tag(--tag);
460
461 // Verify the sizes of various metadata in the system.
462 soc->do_tag(sizeof(Method));
463 soc->do_tag(sizeof(ConstMethod));
464 soc->do_tag(arrayOopDesc::base_offset_in_bytes(T_BYTE));
465 soc->do_tag(sizeof(ConstantPool));
466 soc->do_tag(sizeof(ConstantPoolCache));
467 soc->do_tag(objArrayOopDesc::base_offset_in_bytes());
468 soc->do_tag(typeArrayOopDesc::base_offset_in_bytes(T_BYTE));
469 soc->do_tag(sizeof(Symbol));
470
471 // Dump/restore miscellaneous metadata.
472 Universe::serialize(soc);
473 soc->do_tag(--tag);
474
475 // Dump/restore references to commonly used names and signatures.
476 vmSymbols::serialize(soc);
477 soc->do_tag(--tag);
478
479 // Dump/restore the symbol/string/subgraph_info tables
480 SymbolTable::serialize_shared_table_header(soc);
481 StringTable::serialize_shared_table_header(soc);
482 HeapShared::serialize_subgraph_info_table_header(soc);
483 SystemDictionaryShared::serialize_dictionary_headers(soc);
484
485 JavaClasses::serialize_offsets(soc);
486 InstanceMirrorKlass::serialize_offsets(soc);
487 soc->do_tag(--tag);
488
489 serialize_cloned_cpp_vtptrs(soc);
490 soc->do_tag(--tag);
491
492 soc->do_tag(666);
493 }
494
495 address MetaspaceShared::i2i_entry_code_buffers(size_t total_size) {
496 if (DumpSharedSpaces) {
497 if (_i2i_entry_code_buffers == NULL) {
498 _i2i_entry_code_buffers = (address)misc_code_space_alloc(total_size);
499 _i2i_entry_code_buffers_size = total_size;
500 }
501 } else if (UseSharedSpaces) {
502 assert(_i2i_entry_code_buffers != NULL, "must already been initialized");
503 } else {
504 return NULL;
505 }
506
507 assert(_i2i_entry_code_buffers_size == total_size, "must not change");
508 return _i2i_entry_code_buffers;
509 }
510
511 uintx MetaspaceShared::object_delta_uintx(void* obj) {
512 Arguments::assert_is_dumping_archive();
513 if (DumpSharedSpaces) {
514 assert(shared_rs()->contains(obj), "must be");
515 } else {
516 assert(is_in_shared_metaspace(obj) || DynamicArchive::is_in_target_space(obj), "must be");
517 }
518 address base_address = address(SharedBaseAddress);
519 uintx deltax = address(obj) - base_address;
520 return deltax;
521 }
522
523 // Global object for holding classes that have been loaded. Since this
524 // is run at a safepoint just before exit, this is the entire set of classes.
525 static GrowableArray<Klass*>* _global_klass_objects;
526
527 GrowableArray<Klass*>* MetaspaceShared::collected_klasses() {
528 return _global_klass_objects;
529 }
530
531 static void collect_array_classes(Klass* k) {
532 _global_klass_objects->append_if_missing(k);
533 if (k->is_array_klass()) {
534 // Add in the array classes too
535 ArrayKlass* ak = ArrayKlass::cast(k);
536 Klass* h = ak->higher_dimension();
537 if (h != NULL) {
538 h->array_klasses_do(collect_array_classes);
539 }
540 }
541 }
542
543 class CollectClassesClosure : public KlassClosure {
544 void do_klass(Klass* k) {
545 if (k->is_instance_klass() &&
546 SystemDictionaryShared::is_excluded_class(InstanceKlass::cast(k))) {
547 // Don't add to the _global_klass_objects
548 } else {
549 _global_klass_objects->append_if_missing(k);
550 }
551 if (k->is_array_klass()) {
552 // Add in the array classes too
553 ArrayKlass* ak = ArrayKlass::cast(k);
554 Klass* h = ak->higher_dimension();
555 if (h != NULL) {
556 h->array_klasses_do(collect_array_classes);
557 }
558 }
559 }
560 };
561
562 static void remove_unshareable_in_classes() {
563 for (int i = 0; i < _global_klass_objects->length(); i++) {
564 Klass* k = _global_klass_objects->at(i);
565 if (!k->is_objArray_klass()) {
566 // InstanceKlass and TypeArrayKlass will in turn call remove_unshareable_info
567 // on their array classes.
568 assert(k->is_instance_klass() || k->is_typeArray_klass(), "must be");
569 k->remove_unshareable_info();
570 }
571 }
572 }
573
574 static void remove_java_mirror_in_classes() {
575 for (int i = 0; i < _global_klass_objects->length(); i++) {
576 Klass* k = _global_klass_objects->at(i);
577 if (!k->is_objArray_klass()) {
578 // InstanceKlass and TypeArrayKlass will in turn call remove_unshareable_info
579 // on their array classes.
580 assert(k->is_instance_klass() || k->is_typeArray_klass(), "must be");
581 k->remove_java_mirror();
582 }
583 }
584 }
585
586 static void clear_basic_type_mirrors() {
587 assert(!HeapShared::is_heap_object_archiving_allowed(), "Sanity");
588 Universe::set_int_mirror(NULL);
589 Universe::set_float_mirror(NULL);
590 Universe::set_double_mirror(NULL);
591 Universe::set_byte_mirror(NULL);
592 Universe::set_bool_mirror(NULL);
593 Universe::set_char_mirror(NULL);
594 Universe::set_long_mirror(NULL);
595 Universe::set_short_mirror(NULL);
596 Universe::set_void_mirror(NULL);
597 }
598
599 static void rewrite_nofast_bytecode(const methodHandle& method) {
600 BytecodeStream bcs(method);
601 while (!bcs.is_last_bytecode()) {
602 Bytecodes::Code opcode = bcs.next();
603 switch (opcode) {
604 case Bytecodes::_getfield: *bcs.bcp() = Bytecodes::_nofast_getfield; break;
605 case Bytecodes::_putfield: *bcs.bcp() = Bytecodes::_nofast_putfield; break;
606 case Bytecodes::_aload_0: *bcs.bcp() = Bytecodes::_nofast_aload_0; break;
607 case Bytecodes::_iload: {
608 if (!bcs.is_wide()) {
609 *bcs.bcp() = Bytecodes::_nofast_iload;
610 }
611 break;
612 }
613 default: break;
614 }
615 }
616 }
617
618 // Walk all methods in the class list to ensure that they won't be modified at
619 // run time. This includes:
620 // [1] Rewrite all bytecodes as needed, so that the ConstMethod* will not be modified
621 // at run time by RewriteBytecodes/RewriteFrequentPairs
622 // [2] Assign a fingerprint, so one doesn't need to be assigned at run-time.
623 static void rewrite_nofast_bytecodes_and_calculate_fingerprints(Thread* thread) {
624 for (int i = 0; i < _global_klass_objects->length(); i++) {
625 Klass* k = _global_klass_objects->at(i);
626 if (k->is_instance_klass()) {
627 InstanceKlass* ik = InstanceKlass::cast(k);
628 MetaspaceShared::rewrite_nofast_bytecodes_and_calculate_fingerprints(thread, ik);
629 }
630 }
631 }
632
633 void MetaspaceShared::rewrite_nofast_bytecodes_and_calculate_fingerprints(Thread* thread, InstanceKlass* ik) {
634 for (int i = 0; i < ik->methods()->length(); i++) {
635 methodHandle m(thread, ik->methods()->at(i));
636 rewrite_nofast_bytecode(m);
637 Fingerprinter fp(m);
638 // The side effect of this call sets method's fingerprint field.
639 fp.fingerprint();
640 }
641 }
642
643 // Objects of the Metadata types (such as Klass and ConstantPool) have C++ vtables.
644 // (In GCC this is the field <Type>::_vptr, i.e., first word in the object.)
645 //
646 // Addresses of the vtables and the methods may be different across JVM runs,
647 // if libjvm.so is dynamically loaded at a different base address.
648 //
649 // To ensure that the Metadata objects in the CDS archive always have the correct vtable:
650 //
651 // + at dump time: we redirect the _vptr to point to our own vtables inside
652 // the CDS image
653 // + at run time: we clone the actual contents of the vtables from libjvm.so
654 // into our own tables.
655
656 // Currently, the archive contain ONLY the following types of objects that have C++ vtables.
657 #define CPP_VTABLE_PATCH_TYPES_DO(f) \
658 f(ConstantPool) \
659 f(InstanceKlass) \
660 f(InstanceClassLoaderKlass) \
661 f(InstanceMirrorKlass) \
662 f(InstanceRefKlass) \
663 f(Method) \
664 f(ObjArrayKlass) \
665 f(TypeArrayKlass)
666
667 class CppVtableInfo {
668 intptr_t _vtable_size;
669 intptr_t _cloned_vtable[1];
670 public:
671 static int num_slots(int vtable_size) {
672 return 1 + vtable_size; // Need to add the space occupied by _vtable_size;
673 }
674 int vtable_size() { return int(uintx(_vtable_size)); }
675 void set_vtable_size(int n) { _vtable_size = intptr_t(n); }
676 intptr_t* cloned_vtable() { return &_cloned_vtable[0]; }
677 void zero() { memset(_cloned_vtable, 0, sizeof(intptr_t) * vtable_size()); }
678 // Returns the address of the next CppVtableInfo that can be placed immediately after this CppVtableInfo
679 static size_t byte_size(int vtable_size) {
680 CppVtableInfo i;
681 return pointer_delta(&i._cloned_vtable[vtable_size], &i, sizeof(u1));
682 }
683 };
684
685 template <class T> class CppVtableCloner : public T {
686 static intptr_t* vtable_of(Metadata& m) {
687 return *((intptr_t**)&m);
688 }
689 static CppVtableInfo* _info;
690
691 static int get_vtable_length(const char* name);
692
693 public:
694 // Allocate and initialize the C++ vtable, starting from top, but do not go past end.
695 static intptr_t* allocate(const char* name);
696
697 // Clone the vtable to ...
698 static intptr_t* clone_vtable(const char* name, CppVtableInfo* info);
699
700 static void zero_vtable_clone() {
701 assert(DumpSharedSpaces, "dump-time only");
702 _info->zero();
703 }
704
705 // Switch the vtable pointer to point to the cloned vtable.
706 static void patch(Metadata* obj) {
707 assert(DumpSharedSpaces, "dump-time only");
708 *(void**)obj = (void*)(_info->cloned_vtable());
709 }
710
711 static bool is_valid_shared_object(const T* obj) {
712 intptr_t* vptr = *(intptr_t**)obj;
713 return vptr == _info->cloned_vtable();
714 }
715 };
716
717 template <class T> CppVtableInfo* CppVtableCloner<T>::_info = NULL;
718
719 template <class T>
720 intptr_t* CppVtableCloner<T>::allocate(const char* name) {
721 assert(is_aligned(_md_region.top(), sizeof(intptr_t)), "bad alignment");
722 int n = get_vtable_length(name);
723 _info = (CppVtableInfo*)_md_region.allocate(CppVtableInfo::byte_size(n), sizeof(intptr_t));
724 _info->set_vtable_size(n);
725
726 intptr_t* p = clone_vtable(name, _info);
727 assert((char*)p == _md_region.top(), "must be");
728
729 return _info->cloned_vtable();
730 }
731
732 template <class T>
733 intptr_t* CppVtableCloner<T>::clone_vtable(const char* name, CppVtableInfo* info) {
734 if (!DumpSharedSpaces) {
735 assert(_info == 0, "_info is initialized only at dump time");
736 _info = info; // Remember it -- it will be used by MetaspaceShared::is_valid_shared_method()
737 }
738 T tmp; // Allocate temporary dummy metadata object to get to the original vtable.
739 int n = info->vtable_size();
740 intptr_t* srcvtable = vtable_of(tmp);
741 intptr_t* dstvtable = info->cloned_vtable();
742
743 // We already checked (and, if necessary, adjusted n) when the vtables were allocated, so we are
744 // safe to do memcpy.
745 log_debug(cds, vtables)("Copying %3d vtable entries for %s", n, name);
746 memcpy(dstvtable, srcvtable, sizeof(intptr_t) * n);
747 return dstvtable + n;
748 }
749
750 // To determine the size of the vtable for each type, we use the following
751 // trick by declaring 2 subclasses:
752 //
753 // class CppVtableTesterA: public InstanceKlass {virtual int last_virtual_method() {return 1;} };
754 // class CppVtableTesterB: public InstanceKlass {virtual void* last_virtual_method() {return NULL}; };
755 //
756 // CppVtableTesterA and CppVtableTesterB's vtables have the following properties:
757 // - Their size (N+1) is exactly one more than the size of InstanceKlass's vtable (N)
758 // - The first N entries have are exactly the same as in InstanceKlass's vtable.
759 // - Their last entry is different.
760 //
761 // So to determine the value of N, we just walk CppVtableTesterA and CppVtableTesterB's tables
762 // and find the first entry that's different.
763 //
764 // This works on all C++ compilers supported by Oracle, but you may need to tweak it for more
765 // esoteric compilers.
766
767 template <class T> class CppVtableTesterB: public T {
768 public:
769 virtual int last_virtual_method() {return 1;}
770 };
771
772 template <class T> class CppVtableTesterA : public T {
773 public:
774 virtual void* last_virtual_method() {
775 // Make this different than CppVtableTesterB::last_virtual_method so the C++
776 // compiler/linker won't alias the two functions.
777 return NULL;
778 }
779 };
780
781 template <class T>
782 int CppVtableCloner<T>::get_vtable_length(const char* name) {
783 CppVtableTesterA<T> a;
784 CppVtableTesterB<T> b;
785
786 intptr_t* avtable = vtable_of(a);
787 intptr_t* bvtable = vtable_of(b);
788
789 // Start at slot 1, because slot 0 may be RTTI (on Solaris/Sparc)
790 int vtable_len = 1;
791 for (; ; vtable_len++) {
792 if (avtable[vtable_len] != bvtable[vtable_len]) {
793 break;
794 }
795 }
796 log_debug(cds, vtables)("Found %3d vtable entries for %s", vtable_len, name);
797
798 return vtable_len;
799 }
800
801 #define ALLOC_CPP_VTABLE_CLONE(c) \
802 _cloned_cpp_vtptrs[c##_Kind] = CppVtableCloner<c>::allocate(#c);
803
804 #define CLONE_CPP_VTABLE(c) \
805 p = CppVtableCloner<c>::clone_vtable(#c, (CppVtableInfo*)p);
806
807 #define ZERO_CPP_VTABLE(c) \
808 CppVtableCloner<c>::zero_vtable_clone();
809
810 //------------------------------ for DynamicDumpSharedSpaces - start
811 #define DECLARE_CLONED_VTABLE_KIND(c) c ## _Kind,
812
813 enum {
814 CPP_VTABLE_PATCH_TYPES_DO(DECLARE_CLONED_VTABLE_KIND)
815 _num_cloned_vtable_kinds
816 };
817
818 static intptr_t** _cloned_cpp_vtptrs = NULL;
819
820 void MetaspaceShared::serialize_cloned_cpp_vtptrs(SerializeClosure* soc) {
821 soc->do_ptr((void**)&_cloned_cpp_vtptrs);
822 }
823
824 intptr_t* MetaspaceShared::fix_cpp_vtable_for_dynamic_archive(MetaspaceObj::Type msotype, address obj) {
825 assert(DynamicDumpSharedSpaces, "must");
826 int kind = -1;
827 switch (msotype) {
828 case MetaspaceObj::SymbolType:
829 case MetaspaceObj::TypeArrayU1Type:
830 case MetaspaceObj::TypeArrayU2Type:
831 case MetaspaceObj::TypeArrayU4Type:
832 case MetaspaceObj::TypeArrayU8Type:
833 case MetaspaceObj::TypeArrayOtherType:
834 case MetaspaceObj::ConstMethodType:
835 case MetaspaceObj::ConstantPoolCacheType:
836 case MetaspaceObj::AnnotationsType:
837 case MetaspaceObj::MethodCountersType:
838 // These have no vtables.
839 break;
840 case MetaspaceObj::ClassType:
841 {
842 Klass* k = (Klass*)obj;
843 assert(k->is_klass(), "must be");
844 if (k->is_instance_klass()) {
845 kind = InstanceKlass_Kind;
846 } else {
847 assert(k->is_objArray_klass(),
848 "We shouldn't archive any other klasses in DynamicDumpSharedSpaces");
849 kind = ObjArrayKlass_Kind;
850 }
851 }
852 break;
853
854 case MetaspaceObj::MethodType:
855 {
856 Method* m = (Method*)obj;
857 assert(m->is_method(), "must be");
858 kind = Method_Kind;
859 }
860 break;
861
862 case MetaspaceObj::MethodDataType:
863 // We don't archive MethodData <-- should have been removed in removed_unsharable_info
864 ShouldNotReachHere();
865 break;
866
867 case MetaspaceObj::ConstantPoolType:
868 {
869 ConstantPool *cp = (ConstantPool*)obj;
870 assert(cp->is_constantPool(), "must be");
871 kind = ConstantPool_Kind;
872 }
873 break;
874
875 default:
876 ShouldNotReachHere();
877 }
878
879 if (kind >= 0) {
880 assert(kind < _num_cloned_vtable_kinds, "must be");
881 return _cloned_cpp_vtptrs[kind];
882 } else {
883 return NULL;
884 }
885 }
886
887 //------------------------------ for DynamicDumpSharedSpaces - end
888
889 // This can be called at both dump time and run time.
890 intptr_t* MetaspaceShared::clone_cpp_vtables(intptr_t* p) {
891 assert(DumpSharedSpaces || UseSharedSpaces, "sanity");
892 CPP_VTABLE_PATCH_TYPES_DO(CLONE_CPP_VTABLE);
893 return p;
894 }
895
896 void MetaspaceShared::zero_cpp_vtable_clones_for_writing() {
897 assert(DumpSharedSpaces, "dump-time only");
898 CPP_VTABLE_PATCH_TYPES_DO(ZERO_CPP_VTABLE);
899 }
900
901 // Allocate and initialize the C++ vtables, starting from top, but do not go past end.
902 void MetaspaceShared::allocate_cpp_vtable_clones() {
903 assert(DumpSharedSpaces, "dump-time only");
904 // Layout (each slot is a intptr_t):
905 // [number of slots in the first vtable = n1]
906 // [ <n1> slots for the first vtable]
907 // [number of slots in the first second = n2]
908 // [ <n2> slots for the second vtable]
909 // ...
910 // The order of the vtables is the same as the CPP_VTAB_PATCH_TYPES_DO macro.
911 CPP_VTABLE_PATCH_TYPES_DO(ALLOC_CPP_VTABLE_CLONE);
912 }
913
914 // Switch the vtable pointer to point to the cloned vtable. We assume the
915 // vtable pointer is in first slot in object.
916 void MetaspaceShared::patch_cpp_vtable_pointers() {
917 int n = _global_klass_objects->length();
918 for (int i = 0; i < n; i++) {
919 Klass* obj = _global_klass_objects->at(i);
920 if (obj->is_instance_klass()) {
921 InstanceKlass* ik = InstanceKlass::cast(obj);
922 if (ik->is_class_loader_instance_klass()) {
923 CppVtableCloner<InstanceClassLoaderKlass>::patch(ik);
924 } else if (ik->is_reference_instance_klass()) {
925 CppVtableCloner<InstanceRefKlass>::patch(ik);
926 } else if (ik->is_mirror_instance_klass()) {
927 CppVtableCloner<InstanceMirrorKlass>::patch(ik);
928 } else {
929 CppVtableCloner<InstanceKlass>::patch(ik);
930 }
931 ConstantPool* cp = ik->constants();
932 CppVtableCloner<ConstantPool>::patch(cp);
933 for (int j = 0; j < ik->methods()->length(); j++) {
934 Method* m = ik->methods()->at(j);
935 CppVtableCloner<Method>::patch(m);
936 assert(CppVtableCloner<Method>::is_valid_shared_object(m), "must be");
937 }
938 } else if (obj->is_objArray_klass()) {
939 CppVtableCloner<ObjArrayKlass>::patch(obj);
940 } else {
941 assert(obj->is_typeArray_klass(), "sanity");
942 CppVtableCloner<TypeArrayKlass>::patch(obj);
943 }
944 }
945 }
946
947 bool MetaspaceShared::is_valid_shared_method(const Method* m) {
948 assert(is_in_shared_metaspace(m), "must be");
949 return CppVtableCloner<Method>::is_valid_shared_object(m);
950 }
951
952 void WriteClosure::do_oop(oop* o) {
953 if (*o == NULL) {
954 _dump_region->append_intptr_t(0);
955 } else {
956 assert(HeapShared::is_heap_object_archiving_allowed(),
957 "Archiving heap object is not allowed");
958 _dump_region->append_intptr_t(
959 (intptr_t)CompressedOops::encode_not_null(*o));
960 }
961 }
962
963 void WriteClosure::do_region(u_char* start, size_t size) {
964 assert((intptr_t)start % sizeof(intptr_t) == 0, "bad alignment");
965 assert(size % sizeof(intptr_t) == 0, "bad size");
966 do_tag((int)size);
967 while (size > 0) {
968 _dump_region->append_intptr_t(*(intptr_t*)start);
969 start += sizeof(intptr_t);
970 size -= sizeof(intptr_t);
971 }
972 }
973
974 // This is for dumping detailed statistics for the allocations
975 // in the shared spaces.
976 class DumpAllocStats : public ResourceObj {
977 public:
978
979 // Here's poor man's enum inheritance
980 #define SHAREDSPACE_OBJ_TYPES_DO(f) \
981 METASPACE_OBJ_TYPES_DO(f) \
982 f(SymbolHashentry) \
983 f(SymbolBucket) \
984 f(StringHashentry) \
985 f(StringBucket) \
986 f(Other)
987
988 enum Type {
989 // Types are MetaspaceObj::ClassType, MetaspaceObj::SymbolType, etc
990 SHAREDSPACE_OBJ_TYPES_DO(METASPACE_OBJ_TYPE_DECLARE)
991 _number_of_types
992 };
993
994 static const char * type_name(Type type) {
995 switch(type) {
996 SHAREDSPACE_OBJ_TYPES_DO(METASPACE_OBJ_TYPE_NAME_CASE)
997 default:
998 ShouldNotReachHere();
999 return NULL;
1000 }
1001 }
1002
1003 public:
1004 enum { RO = 0, RW = 1 };
1005
1006 int _counts[2][_number_of_types];
1007 int _bytes [2][_number_of_types];
1008
1009 DumpAllocStats() {
1010 memset(_counts, 0, sizeof(_counts));
1011 memset(_bytes, 0, sizeof(_bytes));
1012 };
1013
1014 void record(MetaspaceObj::Type type, int byte_size, bool read_only) {
1015 assert(int(type) >= 0 && type < MetaspaceObj::_number_of_types, "sanity");
1016 int which = (read_only) ? RO : RW;
1017 _counts[which][type] ++;
1018 _bytes [which][type] += byte_size;
1019 }
1020
1021 void record_other_type(int byte_size, bool read_only) {
1022 int which = (read_only) ? RO : RW;
1023 _bytes [which][OtherType] += byte_size;
1024 }
1025 void print_stats(int ro_all, int rw_all, int mc_all, int md_all);
1026 };
1027
1028 void DumpAllocStats::print_stats(int ro_all, int rw_all, int mc_all, int md_all) {
1029 // Calculate size of data that was not allocated by Metaspace::allocate()
1030 MetaspaceSharedStats *stats = MetaspaceShared::stats();
1031
1032 // symbols
1033 _counts[RO][SymbolHashentryType] = stats->symbol.hashentry_count;
1034 _bytes [RO][SymbolHashentryType] = stats->symbol.hashentry_bytes;
1035
1036 _counts[RO][SymbolBucketType] = stats->symbol.bucket_count;
1037 _bytes [RO][SymbolBucketType] = stats->symbol.bucket_bytes;
1038
1039 // strings
1040 _counts[RO][StringHashentryType] = stats->string.hashentry_count;
1041 _bytes [RO][StringHashentryType] = stats->string.hashentry_bytes;
1042
1043 _counts[RO][StringBucketType] = stats->string.bucket_count;
1044 _bytes [RO][StringBucketType] = stats->string.bucket_bytes;
1045
1046 // TODO: count things like dictionary, vtable, etc
1047 _bytes[RW][OtherType] += mc_all + md_all;
1048 rw_all += mc_all + md_all; // mc/md are mapped Read/Write
1049
1050 // prevent divide-by-zero
1051 if (ro_all < 1) {
1052 ro_all = 1;
1053 }
1054 if (rw_all < 1) {
1055 rw_all = 1;
1056 }
1057
1058 int all_ro_count = 0;
1059 int all_ro_bytes = 0;
1060 int all_rw_count = 0;
1061 int all_rw_bytes = 0;
1062
1063 // To make fmt_stats be a syntactic constant (for format warnings), use #define.
1064 #define fmt_stats "%-20s: %8d %10d %5.1f | %8d %10d %5.1f | %8d %10d %5.1f"
1065 const char *sep = "--------------------+---------------------------+---------------------------+--------------------------";
1066 const char *hdr = " ro_cnt ro_bytes % | rw_cnt rw_bytes % | all_cnt all_bytes %";
1067
1068 LogMessage(cds) msg;
1069
1070 msg.info("Detailed metadata info (excluding st regions; rw stats include md/mc regions):");
1071 msg.info("%s", hdr);
1072 msg.info("%s", sep);
1073 for (int type = 0; type < int(_number_of_types); type ++) {
1074 const char *name = type_name((Type)type);
1075 int ro_count = _counts[RO][type];
1076 int ro_bytes = _bytes [RO][type];
1077 int rw_count = _counts[RW][type];
1078 int rw_bytes = _bytes [RW][type];
1079 int count = ro_count + rw_count;
1080 int bytes = ro_bytes + rw_bytes;
1081
1082 double ro_perc = percent_of(ro_bytes, ro_all);
1083 double rw_perc = percent_of(rw_bytes, rw_all);
1084 double perc = percent_of(bytes, ro_all + rw_all);
1085
1086 msg.info(fmt_stats, name,
1087 ro_count, ro_bytes, ro_perc,
1088 rw_count, rw_bytes, rw_perc,
1089 count, bytes, perc);
1090
1091 all_ro_count += ro_count;
1092 all_ro_bytes += ro_bytes;
1093 all_rw_count += rw_count;
1094 all_rw_bytes += rw_bytes;
1095 }
1096
1097 int all_count = all_ro_count + all_rw_count;
1098 int all_bytes = all_ro_bytes + all_rw_bytes;
1099
1100 double all_ro_perc = percent_of(all_ro_bytes, ro_all);
1101 double all_rw_perc = percent_of(all_rw_bytes, rw_all);
1102 double all_perc = percent_of(all_bytes, ro_all + rw_all);
1103
1104 msg.info("%s", sep);
1105 msg.info(fmt_stats, "Total",
1106 all_ro_count, all_ro_bytes, all_ro_perc,
1107 all_rw_count, all_rw_bytes, all_rw_perc,
1108 all_count, all_bytes, all_perc);
1109
1110 assert(all_ro_bytes == ro_all, "everything should have been counted");
1111 assert(all_rw_bytes == rw_all, "everything should have been counted");
1112
1113 #undef fmt_stats
1114 }
1115
1116 // Populate the shared space.
1117
1118 class VM_PopulateDumpSharedSpace: public VM_Operation {
1119 private:
1120 GrowableArray<MemRegion> *_closed_archive_heap_regions;
1121 GrowableArray<MemRegion> *_open_archive_heap_regions;
1122
1123 GrowableArray<ArchiveHeapOopmapInfo> *_closed_archive_heap_oopmaps;
1124 GrowableArray<ArchiveHeapOopmapInfo> *_open_archive_heap_oopmaps;
1125
1126 void dump_java_heap_objects() NOT_CDS_JAVA_HEAP_RETURN;
1127 void dump_archive_heap_oopmaps() NOT_CDS_JAVA_HEAP_RETURN;
1128 void dump_archive_heap_oopmaps(GrowableArray<MemRegion>* regions,
1129 GrowableArray<ArchiveHeapOopmapInfo>* oopmaps);
1130 void dump_symbols();
1131 char* dump_read_only_tables();
1132 void print_region_stats();
1133 void print_heap_region_stats(GrowableArray<MemRegion> *heap_mem,
1134 const char *name, const size_t total_size);
1135 public:
1136
1137 VMOp_Type type() const { return VMOp_PopulateDumpSharedSpace; }
1138 void doit(); // outline because gdb sucks
1139 static void write_region(FileMapInfo* mapinfo, int region_idx, DumpRegion* dump_region, bool read_only, bool allow_exec) {
1140 mapinfo->write_region(region_idx, dump_region->base(), dump_region->used(), read_only, allow_exec);
1141 }
1142 bool allow_nested_vm_operations() const { return true; }
1143 }; // class VM_PopulateDumpSharedSpace
1144
1145 class SortedSymbolClosure: public SymbolClosure {
1146 GrowableArray<Symbol*> _symbols;
1147 virtual void do_symbol(Symbol** sym) {
1148 assert((*sym)->is_permanent(), "archived symbols must be permanent");
1149 _symbols.append(*sym);
1150 }
1151 static int compare_symbols_by_address(Symbol** a, Symbol** b) {
1152 if (a[0] < b[0]) {
1153 return -1;
1154 } else if (a[0] == b[0]) {
1155 return 0;
1156 } else {
1157 return 1;
1158 }
1159 }
1160
1161 public:
1162 SortedSymbolClosure() {
1163 SymbolTable::symbols_do(this);
1164 _symbols.sort(compare_symbols_by_address);
1165 }
1166 GrowableArray<Symbol*>* get_sorted_symbols() {
1167 return &_symbols;
1168 }
1169 };
1170
1171 // ArchiveCompactor --
1172 //
1173 // This class is the central piece of shared archive compaction -- all metaspace data are
1174 // initially allocated outside of the shared regions. ArchiveCompactor copies the
1175 // metaspace data into their final location in the shared regions.
1176
1177 class ArchiveCompactor : AllStatic {
1178 static const int INITIAL_TABLE_SIZE = 8087;
1179 static const int MAX_TABLE_SIZE = 1000000;
1180
1181 static DumpAllocStats* _alloc_stats;
1182 static SortedSymbolClosure* _ssc;
1183
1184 typedef KVHashtable<address, address, mtInternal> RelocationTable;
1185 static RelocationTable* _new_loc_table;
1186
1187 public:
1188 static void initialize() {
1189 _alloc_stats = new(ResourceObj::C_HEAP, mtInternal)DumpAllocStats;
1190 _new_loc_table = new RelocationTable(INITIAL_TABLE_SIZE);
1191 }
1192 static DumpAllocStats* alloc_stats() {
1193 return _alloc_stats;
1194 }
1195
1196 // Use this when you allocate space with MetaspaceShare::read_only_space_alloc()
1197 // outside of ArchiveCompactor::allocate(). These are usually for misc tables
1198 // that are allocated in the RO space.
1199 class OtherROAllocMark {
1200 char* _oldtop;
1201 public:
1202 OtherROAllocMark() {
1203 _oldtop = _ro_region.top();
1204 }
1205 ~OtherROAllocMark() {
1206 char* newtop = _ro_region.top();
1207 ArchiveCompactor::alloc_stats()->record_other_type(int(newtop - _oldtop), true);
1208 }
1209 };
1210
1211 static void allocate(MetaspaceClosure::Ref* ref, bool read_only) {
1212 address obj = ref->obj();
1213 int bytes = ref->size() * BytesPerWord;
1214 char* p;
1215 size_t alignment = BytesPerWord;
1216 char* oldtop;
1217 char* newtop;
1218
1219 if (read_only) {
1220 oldtop = _ro_region.top();
1221 p = _ro_region.allocate(bytes, alignment);
1222 newtop = _ro_region.top();
1223 } else {
1224 oldtop = _rw_region.top();
1225 if (ref->msotype() == MetaspaceObj::ClassType) {
1226 // Save a pointer immediate in front of an InstanceKlass, so
1227 // we can do a quick lookup from InstanceKlass* -> RunTimeSharedClassInfo*
1228 // without building another hashtable. See RunTimeSharedClassInfo::get_for()
1229 // in systemDictionaryShared.cpp.
1230 Klass* klass = (Klass*)obj;
1231 if (klass->is_instance_klass()) {
1232 SystemDictionaryShared::validate_before_archiving(InstanceKlass::cast(klass));
1233 _rw_region.allocate(sizeof(address), BytesPerWord);
1234 }
1235 }
1236 p = _rw_region.allocate(bytes, alignment);
1237 newtop = _rw_region.top();
1238 }
1239 memcpy(p, obj, bytes);
1240 assert(_new_loc_table->lookup(obj) == NULL, "each object can be relocated at most once");
1241 _new_loc_table->add(obj, (address)p);
1242 log_trace(cds)("Copy: " PTR_FORMAT " ==> " PTR_FORMAT " %d", p2i(obj), p2i(p), bytes);
1243 if (_new_loc_table->maybe_grow(MAX_TABLE_SIZE)) {
1244 log_info(cds, hashtables)("Expanded _new_loc_table to %d", _new_loc_table->table_size());
1245 }
1246 _alloc_stats->record(ref->msotype(), int(newtop - oldtop), read_only);
1247 }
1248
1249 static address get_new_loc(MetaspaceClosure::Ref* ref) {
1250 address* pp = _new_loc_table->lookup(ref->obj());
1251 assert(pp != NULL, "must be");
1252 return *pp;
1253 }
1254
1255 private:
1256 // Makes a shallow copy of visited MetaspaceObj's
1257 class ShallowCopier: public UniqueMetaspaceClosure {
1258 bool _read_only;
1259 public:
1260 ShallowCopier(bool read_only) : _read_only(read_only) {}
1261
1262 virtual bool do_unique_ref(Ref* ref, bool read_only) {
1263 if (read_only == _read_only) {
1264 allocate(ref, read_only);
1265 }
1266 return true; // recurse into ref.obj()
1267 }
1268 };
1269
1270 // Relocate embedded pointers within a MetaspaceObj's shallow copy
1271 class ShallowCopyEmbeddedRefRelocator: public UniqueMetaspaceClosure {
1272 public:
1273 virtual bool do_unique_ref(Ref* ref, bool read_only) {
1274 address new_loc = get_new_loc(ref);
1275 RefRelocator refer;
1276 ref->metaspace_pointers_do_at(&refer, new_loc);
1277 return true; // recurse into ref.obj()
1278 }
1279 };
1280
1281 // Relocate a reference to point to its shallow copy
1282 class RefRelocator: public MetaspaceClosure {
1283 public:
1284 virtual bool do_ref(Ref* ref, bool read_only) {
1285 if (ref->not_null()) {
1286 ref->update(get_new_loc(ref));
1287 }
1288 return false; // Do not recurse.
1289 }
1290 };
1291
1292 #ifdef ASSERT
1293 class IsRefInArchiveChecker: public MetaspaceClosure {
1294 public:
1295 virtual bool do_ref(Ref* ref, bool read_only) {
1296 if (ref->not_null()) {
1297 char* obj = (char*)ref->obj();
1298 assert(_ro_region.contains(obj) || _rw_region.contains(obj),
1299 "must be relocated to point to CDS archive");
1300 }
1301 return false; // Do not recurse.
1302 }
1303 };
1304 #endif
1305
1306 public:
1307 static void copy_and_compact() {
1308 ResourceMark rm;
1309 SortedSymbolClosure the_ssc; // StackObj
1310 _ssc = &the_ssc;
1311
1312 tty->print_cr("Scanning all metaspace objects ... ");
1313 {
1314 // allocate and shallow-copy RW objects, immediately following the MC region
1315 tty->print_cr("Allocating RW objects ... ");
1316 _mc_region.pack(&_rw_region);
1317
1318 ResourceMark rm;
1319 ShallowCopier rw_copier(false);
1320 iterate_roots(&rw_copier);
1321 }
1322 {
1323 // allocate and shallow-copy of RO object, immediately following the RW region
1324 tty->print_cr("Allocating RO objects ... ");
1325 _rw_region.pack(&_ro_region);
1326
1327 ResourceMark rm;
1328 ShallowCopier ro_copier(true);
1329 iterate_roots(&ro_copier);
1330 }
1331 {
1332 tty->print_cr("Relocating embedded pointers ... ");
1333 ResourceMark rm;
1334 ShallowCopyEmbeddedRefRelocator emb_reloc;
1335 iterate_roots(&emb_reloc);
1336 }
1337 {
1338 tty->print_cr("Relocating external roots ... ");
1339 ResourceMark rm;
1340 RefRelocator ext_reloc;
1341 iterate_roots(&ext_reloc);
1342 }
1343
1344 #ifdef ASSERT
1345 {
1346 tty->print_cr("Verifying external roots ... ");
1347 ResourceMark rm;
1348 IsRefInArchiveChecker checker;
1349 iterate_roots(&checker);
1350 }
1351 #endif
1352
1353
1354 // cleanup
1355 _ssc = NULL;
1356 }
1357
1358 // We must relocate the System::_well_known_klasses only after we have copied the
1359 // java objects in during dump_java_heap_objects(): during the object copy, we operate on
1360 // old objects which assert that their klass is the original klass.
1361 static void relocate_well_known_klasses() {
1362 {
1363 tty->print_cr("Relocating SystemDictionary::_well_known_klasses[] ... ");
1364 ResourceMark rm;
1365 RefRelocator ext_reloc;
1366 SystemDictionary::well_known_klasses_do(&ext_reloc);
1367 }
1368 // NOTE: after this point, we shouldn't have any globals that can reach the old
1369 // objects.
1370
1371 // We cannot use any of the objects in the heap anymore (except for the
1372 // shared strings) because their headers no longer point to valid Klasses.
1373 }
1374
1375 static void iterate_roots(MetaspaceClosure* it) {
1376 GrowableArray<Symbol*>* symbols = _ssc->get_sorted_symbols();
1377 for (int i=0; i<symbols->length(); i++) {
1378 it->push(symbols->adr_at(i));
1379 }
1380 if (_global_klass_objects != NULL) {
1381 // Need to fix up the pointers
1382 for (int i = 0; i < _global_klass_objects->length(); i++) {
1383 // NOTE -- this requires that the vtable is NOT yet patched, or else we are hosed.
1384 it->push(_global_klass_objects->adr_at(i));
1385 }
1386 }
1387 FileMapInfo::metaspace_pointers_do(it);
1388 SystemDictionaryShared::dumptime_classes_do(it);
1389 Universe::metaspace_pointers_do(it);
1390 SymbolTable::metaspace_pointers_do(it);
1391 vmSymbols::metaspace_pointers_do(it);
1392
1393 it->finish();
1394 }
1395
1396 static Klass* get_relocated_klass(Klass* orig_klass) {
1397 assert(DumpSharedSpaces, "dump time only");
1398 address* pp = _new_loc_table->lookup((address)orig_klass);
1399 assert(pp != NULL, "must be");
1400 Klass* klass = (Klass*)(*pp);
1401 assert(klass->is_klass(), "must be");
1402 return klass;
1403 }
1404 };
1405
1406 DumpAllocStats* ArchiveCompactor::_alloc_stats;
1407 SortedSymbolClosure* ArchiveCompactor::_ssc;
1408 ArchiveCompactor::RelocationTable* ArchiveCompactor::_new_loc_table;
1409
1410 void VM_PopulateDumpSharedSpace::dump_symbols() {
1411 tty->print_cr("Dumping symbol table ...");
1412
1413 NOT_PRODUCT(SymbolTable::verify());
1414 SymbolTable::write_to_archive();
1415 }
1416
1417 char* VM_PopulateDumpSharedSpace::dump_read_only_tables() {
1418 ArchiveCompactor::OtherROAllocMark mark;
1419
1420 tty->print("Removing java_mirror ... ");
1421 if (!HeapShared::is_heap_object_archiving_allowed()) {
1422 clear_basic_type_mirrors();
1423 }
1424 remove_java_mirror_in_classes();
1425 tty->print_cr("done. ");
1426
1427 SystemDictionaryShared::write_to_archive();
1428
1429 size_t vtptrs_bytes = _num_cloned_vtable_kinds * sizeof(intptr_t*);
1430 _cloned_cpp_vtptrs = (intptr_t**)_ro_region.allocate(vtptrs_bytes, sizeof(intptr_t*));
1431
1432 // Write the other data to the output array.
1433 char* start = _ro_region.top();
1434 WriteClosure wc(&_ro_region);
1435 MetaspaceShared::serialize(&wc);
1436
1437 // Write the bitmaps for patching the archive heap regions
1438 dump_archive_heap_oopmaps();
1439
1440 return start;
1441 }
1442
1443 void VM_PopulateDumpSharedSpace::doit() {
1444 // We should no longer allocate anything from the metaspace, so that:
1445 //
1446 // (1) Metaspace::allocate might trigger GC if we have run out of
1447 // committed metaspace, but we can't GC because we're running
1448 // in the VM thread.
1449 // (2) ArchiveCompactor needs to work with a stable set of MetaspaceObjs.
1450 Metaspace::freeze();
1451 DEBUG_ONLY(SystemDictionaryShared::NoClassLoadingMark nclm);
1452
1453 Thread* THREAD = VMThread::vm_thread();
1454
1455 FileMapInfo::check_nonempty_dir_in_shared_path_table();
1456
1457 NOT_PRODUCT(SystemDictionary::verify();)
1458 // The following guarantee is meant to ensure that no loader constraints
1459 // exist yet, since the constraints table is not shared. This becomes
1460 // more important now that we don't re-initialize vtables/itables for
1461 // shared classes at runtime, where constraints were previously created.
1462 guarantee(SystemDictionary::constraints()->number_of_entries() == 0,
1463 "loader constraints are not saved");
1464 guarantee(SystemDictionary::placeholders()->number_of_entries() == 0,
1465 "placeholders are not saved");
1466
1467 // At this point, many classes have been loaded.
1468 // Gather systemDictionary classes in a global array and do everything to
1469 // that so we don't have to walk the SystemDictionary again.
1470 SystemDictionaryShared::check_excluded_classes();
1471 _global_klass_objects = new GrowableArray<Klass*>(1000);
1472 CollectClassesClosure collect_classes;
1473 ClassLoaderDataGraph::loaded_classes_do(&collect_classes);
1474
1475 tty->print_cr("Number of classes %d", _global_klass_objects->length());
1476 {
1477 int num_type_array = 0, num_obj_array = 0, num_inst = 0;
1478 for (int i = 0; i < _global_klass_objects->length(); i++) {
1479 Klass* k = _global_klass_objects->at(i);
1480 if (k->is_instance_klass()) {
1481 num_inst ++;
1482 } else if (k->is_objArray_klass()) {
1483 num_obj_array ++;
1484 } else {
1485 assert(k->is_typeArray_klass(), "sanity");
1486 num_type_array ++;
1487 }
1488 }
1489 tty->print_cr(" instance classes = %5d", num_inst);
1490 tty->print_cr(" obj array classes = %5d", num_obj_array);
1491 tty->print_cr(" type array classes = %5d", num_type_array);
1492 }
1493
1494 // Ensure the ConstMethods won't be modified at run-time
1495 tty->print("Updating ConstMethods ... ");
1496 rewrite_nofast_bytecodes_and_calculate_fingerprints(THREAD);
1497 tty->print_cr("done. ");
1498
1499 // Remove all references outside the metadata
1500 tty->print("Removing unshareable information ... ");
1501 remove_unshareable_in_classes();
1502 tty->print_cr("done. ");
1503
1504 ArchiveCompactor::initialize();
1505 ArchiveCompactor::copy_and_compact();
1506
1507 dump_symbols();
1508
1509 // Dump supported java heap objects
1510 _closed_archive_heap_regions = NULL;
1511 _open_archive_heap_regions = NULL;
1512 dump_java_heap_objects();
1513
1514 ArchiveCompactor::relocate_well_known_klasses();
1515
1516 char* serialized_data_start = dump_read_only_tables();
1517 _ro_region.pack(&_md_region);
1518
1519 char* vtbl_list = _md_region.top();
1520 MetaspaceShared::allocate_cpp_vtable_clones();
1521 _md_region.pack();
1522
1523 // The 4 core spaces are allocated consecutively mc->rw->ro->md, so there total size
1524 // is just the spaces between the two ends.
1525 size_t core_spaces_size = _md_region.end() - _mc_region.base();
1526 assert(core_spaces_size == (size_t)align_up(core_spaces_size, Metaspace::reserve_alignment()),
1527 "should already be aligned");
1528
1529 // During patching, some virtual methods may be called, so at this point
1530 // the vtables must contain valid methods (as filled in by CppVtableCloner::allocate).
1531 MetaspaceShared::patch_cpp_vtable_pointers();
1532
1533 // The vtable clones contain addresses of the current process.
1534 // We don't want to write these addresses into the archive.
1535 MetaspaceShared::zero_cpp_vtable_clones_for_writing();
1536
1537 // Create and write the archive file that maps the shared spaces.
1538
1539 FileMapInfo* mapinfo = new FileMapInfo(true);
1540 mapinfo->populate_header(os::vm_allocation_granularity());
1541 mapinfo->set_serialized_data_start(serialized_data_start);
1542 mapinfo->set_misc_data_patching_start(vtbl_list);
1543 mapinfo->set_i2i_entry_code_buffers(MetaspaceShared::i2i_entry_code_buffers(),
1544 MetaspaceShared::i2i_entry_code_buffers_size());
1545 mapinfo->set_core_spaces_size(core_spaces_size);
1546 mapinfo->open_for_write();
1547
1548 // NOTE: md contains the trampoline code for method entries, which are patched at run time,
1549 // so it needs to be read/write.
1550 write_region(mapinfo, MetaspaceShared::mc, &_mc_region, /*read_only=*/false,/*allow_exec=*/true);
1551 write_region(mapinfo, MetaspaceShared::rw, &_rw_region, /*read_only=*/false,/*allow_exec=*/false);
1552 write_region(mapinfo, MetaspaceShared::ro, &_ro_region, /*read_only=*/true, /*allow_exec=*/false);
1553 write_region(mapinfo, MetaspaceShared::md, &_md_region, /*read_only=*/false,/*allow_exec=*/false);
1554
1555 _total_closed_archive_region_size = mapinfo->write_archive_heap_regions(
1556 _closed_archive_heap_regions,
1557 _closed_archive_heap_oopmaps,
1558 MetaspaceShared::first_closed_archive_heap_region,
1559 MetaspaceShared::max_closed_archive_heap_region);
1560 _total_open_archive_region_size = mapinfo->write_archive_heap_regions(
1561 _open_archive_heap_regions,
1562 _open_archive_heap_oopmaps,
1563 MetaspaceShared::first_open_archive_heap_region,
1564 MetaspaceShared::max_open_archive_heap_region);
1565
1566 mapinfo->set_header_crc(mapinfo->compute_header_crc());
1567 mapinfo->write_header();
1568 mapinfo->close();
1569
1570 // Restore the vtable in case we invoke any virtual methods.
1571 MetaspaceShared::clone_cpp_vtables((intptr_t*)vtbl_list);
1572
1573 print_region_stats();
1574
1575 if (log_is_enabled(Info, cds)) {
1576 ArchiveCompactor::alloc_stats()->print_stats(int(_ro_region.used()), int(_rw_region.used()),
1577 int(_mc_region.used()), int(_md_region.used()));
1578 }
1579
1580 if (PrintSystemDictionaryAtExit) {
1581 SystemDictionary::print();
1582 }
1583
1584 if (AllowArchivingWithJavaAgent) {
1585 warning("This archive was created with AllowArchivingWithJavaAgent. It should be used "
1586 "for testing purposes only and should not be used in a production environment");
1587 }
1588
1589 // There may be other pending VM operations that operate on the InstanceKlasses,
1590 // which will fail because InstanceKlasses::remove_unshareable_info()
1591 // has been called. Forget these operations and exit the VM directly.
1592 vm_direct_exit(0);
1593 }
1594
1595 void VM_PopulateDumpSharedSpace::print_region_stats() {
1596 // Print statistics of all the regions
1597 const size_t total_reserved = _ro_region.reserved() + _rw_region.reserved() +
1598 _mc_region.reserved() + _md_region.reserved() +
1599 _total_closed_archive_region_size +
1600 _total_open_archive_region_size;
1601 const size_t total_bytes = _ro_region.used() + _rw_region.used() +
1602 _mc_region.used() + _md_region.used() +
1603 _total_closed_archive_region_size +
1604 _total_open_archive_region_size;
1605 const double total_u_perc = percent_of(total_bytes, total_reserved);
1606
1607 _mc_region.print(total_reserved);
1608 _rw_region.print(total_reserved);
1609 _ro_region.print(total_reserved);
1610 _md_region.print(total_reserved);
1611 print_heap_region_stats(_closed_archive_heap_regions, "ca", total_reserved);
1612 print_heap_region_stats(_open_archive_heap_regions, "oa", total_reserved);
1613
1614 tty->print_cr("total : " SIZE_FORMAT_W(9) " [100.0%% of total] out of " SIZE_FORMAT_W(9) " bytes [%5.1f%% used]",
1615 total_bytes, total_reserved, total_u_perc);
1616 }
1617
1618 void VM_PopulateDumpSharedSpace::print_heap_region_stats(GrowableArray<MemRegion> *heap_mem,
1619 const char *name, const size_t total_size) {
1620 int arr_len = heap_mem == NULL ? 0 : heap_mem->length();
1621 for (int i = 0; i < arr_len; i++) {
1622 char* start = (char*)heap_mem->at(i).start();
1623 size_t size = heap_mem->at(i).byte_size();
1624 char* top = start + size;
1625 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,
1626 name, i, size, size/double(total_size)*100.0, size, p2i(start));
1627
1628 }
1629 }
1630
1631 // Update a Java object to point its Klass* to the new location after
1632 // shared archive has been compacted.
1633 void MetaspaceShared::relocate_klass_ptr(oop o) {
1634 assert(DumpSharedSpaces, "sanity");
1635 Klass* k = ArchiveCompactor::get_relocated_klass(o->klass());
1636 o->set_klass(k);
1637 }
1638
1639 Klass* MetaspaceShared::get_relocated_klass(Klass *k) {
1640 assert(DumpSharedSpaces, "sanity");
1641 return ArchiveCompactor::get_relocated_klass(k);
1642 }
1643
1644 class LinkSharedClassesClosure : public KlassClosure {
1645 Thread* THREAD;
1646 bool _made_progress;
1647 public:
1648 LinkSharedClassesClosure(Thread* thread) : THREAD(thread), _made_progress(false) {}
1649
1650 void reset() { _made_progress = false; }
1651 bool made_progress() const { return _made_progress; }
1652
1653 void do_klass(Klass* k) {
1654 if (k->is_instance_klass()) {
1655 InstanceKlass* ik = InstanceKlass::cast(k);
1656 // Link the class to cause the bytecodes to be rewritten and the
1657 // cpcache to be created. Class verification is done according
1658 // to -Xverify setting.
1659 _made_progress |= MetaspaceShared::try_link_class(ik, THREAD);
1660 guarantee(!HAS_PENDING_EXCEPTION, "exception in link_class");
1661
1662 ik->constants()->resolve_class_constants(THREAD);
1663 }
1664 }
1665 };
1666
1667 class CheckSharedClassesClosure : public KlassClosure {
1668 bool _made_progress;
1669 public:
1670 CheckSharedClassesClosure() : _made_progress(false) {}
1671
1672 void reset() { _made_progress = false; }
1673 bool made_progress() const { return _made_progress; }
1674 void do_klass(Klass* k) {
1675 if (k->is_instance_klass() && InstanceKlass::cast(k)->check_sharing_error_state()) {
1676 _made_progress = true;
1677 }
1678 }
1679 };
1680
1681 void MetaspaceShared::link_and_cleanup_shared_classes(TRAPS) {
1682 // We need to iterate because verification may cause additional classes
1683 // to be loaded.
1684 LinkSharedClassesClosure link_closure(THREAD);
1685 do {
1686 link_closure.reset();
1687 ClassLoaderDataGraph::unlocked_loaded_classes_do(&link_closure);
1688 guarantee(!HAS_PENDING_EXCEPTION, "exception in link_class");
1689 } while (link_closure.made_progress());
1690
1691 if (_has_error_classes) {
1692 // Mark all classes whose super class or interfaces failed verification.
1693 CheckSharedClassesClosure check_closure;
1694 do {
1695 // Not completely sure if we need to do this iteratively. Anyway,
1696 // we should come here only if there are unverifiable classes, which
1697 // shouldn't happen in normal cases. So better safe than sorry.
1698 check_closure.reset();
1699 ClassLoaderDataGraph::unlocked_loaded_classes_do(&check_closure);
1700 } while (check_closure.made_progress());
1701 }
1702 }
1703
1704 void MetaspaceShared::prepare_for_dumping() {
1705 Arguments::check_unsupported_dumping_properties();
1706 ClassLoader::initialize_shared_path();
1707 }
1708
1709 // Preload classes from a list, populate the shared spaces and dump to a
1710 // file.
1711 void MetaspaceShared::preload_and_dump(TRAPS) {
1712 { TraceTime timer("Dump Shared Spaces", TRACETIME_LOG(Info, startuptime));
1713 ResourceMark rm;
1714 char class_list_path_str[JVM_MAXPATHLEN];
1715 // Preload classes to be shared.
1716 const char* class_list_path;
1717 if (SharedClassListFile == NULL) {
1718 // Construct the path to the class list (in jre/lib)
1719 // Walk up two directories from the location of the VM and
1720 // optionally tack on "lib" (depending on platform)
1721 os::jvm_path(class_list_path_str, sizeof(class_list_path_str));
1722 for (int i = 0; i < 3; i++) {
1723 char *end = strrchr(class_list_path_str, *os::file_separator());
1724 if (end != NULL) *end = '\0';
1725 }
1726 int class_list_path_len = (int)strlen(class_list_path_str);
1727 if (class_list_path_len >= 3) {
1728 if (strcmp(class_list_path_str + class_list_path_len - 3, "lib") != 0) {
1729 if (class_list_path_len < JVM_MAXPATHLEN - 4) {
1730 jio_snprintf(class_list_path_str + class_list_path_len,
1731 sizeof(class_list_path_str) - class_list_path_len,
1732 "%slib", os::file_separator());
1733 class_list_path_len += 4;
1734 }
1735 }
1736 }
1737 if (class_list_path_len < JVM_MAXPATHLEN - 10) {
1738 jio_snprintf(class_list_path_str + class_list_path_len,
1739 sizeof(class_list_path_str) - class_list_path_len,
1740 "%sclasslist", os::file_separator());
1741 }
1742 class_list_path = class_list_path_str;
1743 } else {
1744 class_list_path = SharedClassListFile;
1745 }
1746
1747 tty->print_cr("Loading classes to share ...");
1748 _has_error_classes = false;
1749 int class_count = preload_classes(class_list_path, THREAD);
1750 if (ExtraSharedClassListFile) {
1751 class_count += preload_classes(ExtraSharedClassListFile, THREAD);
1752 }
1753 tty->print_cr("Loading classes to share: done.");
1754
1755 log_info(cds)("Shared spaces: preloaded %d classes", class_count);
1756
1757 if (SharedArchiveConfigFile) {
1758 tty->print_cr("Reading extra data from %s ...", SharedArchiveConfigFile);
1759 read_extra_data(SharedArchiveConfigFile, THREAD);
1760 }
1761 tty->print_cr("Reading extra data: done.");
1762
1763 HeapShared::init_subgraph_entry_fields(THREAD);
1764
1765 // Rewrite and link classes
1766 tty->print_cr("Rewriting and linking classes ...");
1767
1768 // Link any classes which got missed. This would happen if we have loaded classes that
1769 // were not explicitly specified in the classlist. E.g., if an interface implemented by class K
1770 // fails verification, all other interfaces that were not specified in the classlist but
1771 // are implemented by K are not verified.
1772 link_and_cleanup_shared_classes(CATCH);
1773 tty->print_cr("Rewriting and linking classes: done");
1774
1775 if (HeapShared::is_heap_object_archiving_allowed()) {
1776 // Avoid fragmentation while archiving heap objects.
1777 Universe::heap()->soft_ref_policy()->set_should_clear_all_soft_refs(true);
1778 Universe::heap()->collect(GCCause::_archive_time_gc);
1779 Universe::heap()->soft_ref_policy()->set_should_clear_all_soft_refs(false);
1780 }
1781
1782 VM_PopulateDumpSharedSpace op;
1783 VMThread::execute(&op);
1784 }
1785 }
1786
1787
1788 int MetaspaceShared::preload_classes(const char* class_list_path, TRAPS) {
1789 ClassListParser parser(class_list_path);
1790 int class_count = 0;
1791
1792 while (parser.parse_one_line()) {
1793 Klass* klass = parser.load_current_class(THREAD);
1794 if (HAS_PENDING_EXCEPTION) {
1795 if (klass == NULL &&
1796 (PENDING_EXCEPTION->klass()->name() == vmSymbols::java_lang_ClassNotFoundException())) {
1797 // print a warning only when the pending exception is class not found
1798 log_warning(cds)("Preload Warning: Cannot find %s", parser.current_class_name());
1799 }
1800 CLEAR_PENDING_EXCEPTION;
1801 }
1802 if (klass != NULL) {
1803 if (log_is_enabled(Trace, cds)) {
1804 ResourceMark rm;
1805 log_trace(cds)("Shared spaces preloaded: %s", klass->external_name());
1806 }
1807
1808 if (klass->is_instance_klass()) {
1809 InstanceKlass* ik = InstanceKlass::cast(klass);
1810
1811 // Link the class to cause the bytecodes to be rewritten and the
1812 // cpcache to be created. The linking is done as soon as classes
1813 // are loaded in order that the related data structures (klass and
1814 // cpCache) are located together.
1815 try_link_class(ik, THREAD);
1816 guarantee(!HAS_PENDING_EXCEPTION, "exception in link_class");
1817 }
1818
1819 class_count++;
1820 }
1821 }
1822
1823 return class_count;
1824 }
1825
1826 // Returns true if the class's status has changed
1827 bool MetaspaceShared::try_link_class(InstanceKlass* ik, TRAPS) {
1828 assert(DumpSharedSpaces, "should only be called during dumping");
1829 if (ik->init_state() < InstanceKlass::linked) {
1830 bool saved = BytecodeVerificationLocal;
1831 if (ik->loader_type() == 0 && ik->class_loader() == NULL) {
1832 // The verification decision is based on BytecodeVerificationRemote
1833 // for non-system classes. Since we are using the NULL classloader
1834 // to load non-system classes for customized class loaders during dumping,
1835 // we need to temporarily change BytecodeVerificationLocal to be the same as
1836 // BytecodeVerificationRemote. Note this can cause the parent system
1837 // classes also being verified. The extra overhead is acceptable during
1838 // dumping.
1839 BytecodeVerificationLocal = BytecodeVerificationRemote;
1840 }
1841 ik->link_class(THREAD);
1842 if (HAS_PENDING_EXCEPTION) {
1843 ResourceMark rm;
1844 log_warning(cds)("Preload Warning: Verification failed for %s",
1845 ik->external_name());
1846 CLEAR_PENDING_EXCEPTION;
1847 ik->set_in_error_state();
1848 _has_error_classes = true;
1849 }
1850 BytecodeVerificationLocal = saved;
1851 return true;
1852 } else {
1853 return false;
1854 }
1855 }
1856
1857 #if INCLUDE_CDS_JAVA_HEAP
1858 void VM_PopulateDumpSharedSpace::dump_java_heap_objects() {
1859 // The closed and open archive heap space has maximum two regions.
1860 // See FileMapInfo::write_archive_heap_regions() for details.
1861 _closed_archive_heap_regions = new GrowableArray<MemRegion>(2);
1862 _open_archive_heap_regions = new GrowableArray<MemRegion>(2);
1863 HeapShared::archive_java_heap_objects(_closed_archive_heap_regions,
1864 _open_archive_heap_regions);
1865 ArchiveCompactor::OtherROAllocMark mark;
1866 HeapShared::write_subgraph_info_table();
1867 }
1868
1869 void VM_PopulateDumpSharedSpace::dump_archive_heap_oopmaps() {
1870 if (HeapShared::is_heap_object_archiving_allowed()) {
1871 _closed_archive_heap_oopmaps = new GrowableArray<ArchiveHeapOopmapInfo>(2);
1872 dump_archive_heap_oopmaps(_closed_archive_heap_regions, _closed_archive_heap_oopmaps);
1873
1874 _open_archive_heap_oopmaps = new GrowableArray<ArchiveHeapOopmapInfo>(2);
1875 dump_archive_heap_oopmaps(_open_archive_heap_regions, _open_archive_heap_oopmaps);
1876 }
1877 }
1878
1879 void VM_PopulateDumpSharedSpace::dump_archive_heap_oopmaps(GrowableArray<MemRegion>* regions,
1880 GrowableArray<ArchiveHeapOopmapInfo>* oopmaps) {
1881 for (int i=0; i<regions->length(); i++) {
1882 ResourceBitMap oopmap = HeapShared::calculate_oopmap(regions->at(i));
1883 size_t size_in_bits = oopmap.size();
1884 size_t size_in_bytes = oopmap.size_in_bytes();
1885 uintptr_t* buffer = (uintptr_t*)_ro_region.allocate(size_in_bytes, sizeof(intptr_t));
1886 oopmap.write_to(buffer, size_in_bytes);
1887 log_info(cds)("Oopmap = " INTPTR_FORMAT " (" SIZE_FORMAT_W(6) " bytes) for heap region "
1888 INTPTR_FORMAT " (" SIZE_FORMAT_W(8) " bytes)",
1889 p2i(buffer), size_in_bytes,
1890 p2i(regions->at(i).start()), regions->at(i).byte_size());
1891
1892 ArchiveHeapOopmapInfo info;
1893 info._oopmap = (address)buffer;
1894 info._oopmap_size_in_bits = size_in_bits;
1895 oopmaps->append(info);
1896 }
1897 }
1898 #endif // INCLUDE_CDS_JAVA_HEAP
1899
1900 void ReadClosure::do_ptr(void** p) {
1901 assert(*p == NULL, "initializing previous initialized pointer.");
1902 intptr_t obj = nextPtr();
1903 assert((intptr_t)obj >= 0 || (intptr_t)obj < -100,
1904 "hit tag while initializing ptrs.");
1905 *p = (void*)obj;
1906 }
1907
1908 void ReadClosure::do_u4(u4* p) {
1909 intptr_t obj = nextPtr();
1910 *p = (u4)(uintx(obj));
1911 }
1912
1913 void ReadClosure::do_bool(bool* p) {
1914 intptr_t obj = nextPtr();
1915 *p = (bool)(uintx(obj));
1916 }
1917
1918 void ReadClosure::do_tag(int tag) {
1919 int old_tag;
1920 old_tag = (int)(intptr_t)nextPtr();
1921 // do_int(&old_tag);
1922 assert(tag == old_tag, "old tag doesn't match");
1923 FileMapInfo::assert_mark(tag == old_tag);
1924 }
1925
1926 void ReadClosure::do_oop(oop *p) {
1927 narrowOop o = (narrowOop)nextPtr();
1928 if (o == 0 || !HeapShared::open_archive_heap_region_mapped()) {
1929 p = NULL;
1930 } else {
1931 assert(HeapShared::is_heap_object_archiving_allowed(),
1932 "Archived heap object is not allowed");
1933 assert(HeapShared::open_archive_heap_region_mapped(),
1934 "Open archive heap region is not mapped");
1935 *p = HeapShared::decode_from_archive(o);
1936 }
1937 }
1938
1939 void ReadClosure::do_region(u_char* start, size_t size) {
1940 assert((intptr_t)start % sizeof(intptr_t) == 0, "bad alignment");
1941 assert(size % sizeof(intptr_t) == 0, "bad size");
1942 do_tag((int)size);
1943 while (size > 0) {
1944 *(intptr_t*)start = nextPtr();
1945 start += sizeof(intptr_t);
1946 size -= sizeof(intptr_t);
1947 }
1948 }
1949
1950 void MetaspaceShared::set_shared_metaspace_range(void* base, void* top) {
1951 _shared_metaspace_static_top = top;
1952 MetaspaceObj::set_shared_metaspace_range(base, top);
1953 }
1954
1955 // Return true if given address is in the misc data region
1956 bool MetaspaceShared::is_in_shared_region(const void* p, int idx) {
1957 return UseSharedSpaces && FileMapInfo::current_info()->is_in_shared_region(p, idx);
1958 }
1959
1960 bool MetaspaceShared::is_in_trampoline_frame(address addr) {
1961 if (UseSharedSpaces && is_in_shared_region(addr, MetaspaceShared::mc)) {
1962 return true;
1963 }
1964 return false;
1965 }
1966
1967 bool MetaspaceShared::is_shared_dynamic(void* p) {
1968 if ((p < MetaspaceObj::shared_metaspace_top()) &&
1969 (p >= _shared_metaspace_static_top)) {
1970 return true;
1971 } else {
1972 return false;
1973 }
1974 }
1975
1976 // Map shared spaces at requested addresses and return if succeeded.
1977 bool MetaspaceShared::map_shared_spaces(FileMapInfo* mapinfo) {
1978 size_t image_alignment = mapinfo->alignment();
1979
1980 #ifndef _WINDOWS
1981 // Map in the shared memory and then map the regions on top of it.
1982 // On Windows, don't map the memory here because it will cause the
1983 // mappings of the regions to fail.
1984 ReservedSpace shared_rs = mapinfo->reserve_shared_memory();
1985 if (!shared_rs.is_reserved()) return false;
1986 #endif
1987
1988 assert(!DumpSharedSpaces, "Should not be called with DumpSharedSpaces");
1989
1990 // Map each shared region
1991 int regions[] = {mc, rw, ro, md};
1992 size_t len = sizeof(regions)/sizeof(int);
1993 char* saved_base[] = {NULL, NULL, NULL, NULL};
1994 char* top = mapinfo->map_regions(regions, saved_base, len );
1995
1996 if (top != NULL &&
1997 (image_alignment == (size_t)os::vm_allocation_granularity()) &&
1998 mapinfo->validate_shared_path_table()) {
1999 // Success -- set up MetaspaceObj::_shared_metaspace_{base,top} for
2000 // fast checking in MetaspaceShared::is_in_shared_metaspace() and
2001 // MetaspaceObj::is_shared().
2002 _core_spaces_size = mapinfo->core_spaces_size();
2003 set_shared_metaspace_range((void*)saved_base[0], (void*)top);
2004 return true;
2005 } else {
2006 mapinfo->unmap_regions(regions, saved_base, len);
2007 #ifndef _WINDOWS
2008 // Release the entire mapped region
2009 shared_rs.release();
2010 #endif
2011 // If -Xshare:on is specified, print out the error message and exit VM,
2012 // otherwise, set UseSharedSpaces to false and continue.
2013 if (RequireSharedSpaces || PrintSharedArchiveAndExit) {
2014 vm_exit_during_initialization("Unable to use shared archive.", "Failed map_region for using -Xshare:on.");
2015 } else {
2016 FLAG_SET_DEFAULT(UseSharedSpaces, false);
2017 }
2018 return false;
2019 }
2020 }
2021
2022 // Read the miscellaneous data from the shared file, and
2023 // serialize it out to its various destinations.
2024
2025 void MetaspaceShared::initialize_shared_spaces() {
2026 FileMapInfo *mapinfo = FileMapInfo::current_info();
2027 _i2i_entry_code_buffers = mapinfo->i2i_entry_code_buffers();
2028 _i2i_entry_code_buffers_size = mapinfo->i2i_entry_code_buffers_size();
2029 // _core_spaces_size is loaded from the shared archive immediatelly after mapping
2030 assert(_core_spaces_size == mapinfo->core_spaces_size(), "sanity");
2031 char* buffer = mapinfo->misc_data_patching_start();
2032 clone_cpp_vtables((intptr_t*)buffer);
2033
2034 // Verify various attributes of the archive, plus initialize the
2035 // shared string/symbol tables
2036 buffer = mapinfo->serialized_data_start();
2037 intptr_t* array = (intptr_t*)buffer;
2038 ReadClosure rc(&array);
2039 serialize(&rc);
2040
2041 // Initialize the run-time symbol table.
2042 SymbolTable::create_table();
2043
2044 mapinfo->patch_archived_heap_embedded_pointers();
2045
2046 // Close the mapinfo file
2047 mapinfo->close();
2048
2049 if (PrintSharedArchiveAndExit) {
2050 if (PrintSharedDictionary) {
2051 tty->print_cr("\nShared classes:\n");
2052 SystemDictionaryShared::print_on(tty);
2053 }
2054 if (_archive_loading_failed) {
2055 tty->print_cr("archive is invalid");
2056 vm_exit(1);
2057 } else {
2058 tty->print_cr("archive is valid");
2059 vm_exit(0);
2060 }
2061 }
2062 }
2063
2064 // JVM/TI RedefineClasses() support:
2065 bool MetaspaceShared::remap_shared_readonly_as_readwrite() {
2066 assert(SafepointSynchronize::is_at_safepoint(), "must be at safepoint");
2067
2068 if (UseSharedSpaces) {
2069 // remap the shared readonly space to shared readwrite, private
2070 FileMapInfo* mapinfo = FileMapInfo::current_info();
2071 if (!mapinfo->remap_shared_readonly_as_readwrite()) {
2072 return false;
2073 }
2074 if (FileMapInfo::dynamic_info() != NULL) {
2075 mapinfo = FileMapInfo::dynamic_info();
2076 if (!mapinfo->remap_shared_readonly_as_readwrite()) {
2077 return false;
2078 }
2079 }
2080 _remapped_readwrite = true;
2081 }
2082 return true;
2083 }
2084
2085 void MetaspaceShared::report_out_of_space(const char* name, size_t needed_bytes) {
2086 // This is highly unlikely to happen on 64-bits because we have reserved a 4GB space.
2087 // On 32-bit we reserve only 256MB so you could run out of space with 100,000 classes
2088 // or so.
2089 _mc_region.print_out_of_space_msg(name, needed_bytes);
2090 _rw_region.print_out_of_space_msg(name, needed_bytes);
2091 _ro_region.print_out_of_space_msg(name, needed_bytes);
2092 _md_region.print_out_of_space_msg(name, needed_bytes);
2093
2094 vm_exit_during_initialization(err_msg("Unable to allocate from '%s' region", name),
2095 "Please reduce the number of shared classes.");
2096 }