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 assert(DumpSharedSpaces || DynamicDumpSharedSpaces, "dump-time only");
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 assert(DumpSharedSpaces || DynamicDumpSharedSpaces,
513 "supported only for dumping");
514 if (DumpSharedSpaces) {
515 assert(shared_rs()->contains(obj), "must be");
516 } else {
517 assert(is_in_shared_metaspace(obj) || DynamicArchive::is_in_target_space(obj), "must be");
518 }
519 address base_address = address(SharedBaseAddress);
520 uintx deltax = address(obj) - base_address;
521 return deltax;
522 }
523
524 // Global object for holding classes that have been loaded. Since this
525 // is run at a safepoint just before exit, this is the entire set of classes.
526 static GrowableArray<Klass*>* _global_klass_objects;
527
528 GrowableArray<Klass*>* MetaspaceShared::collected_klasses() {
529 return _global_klass_objects;
530 }
531
532 static void collect_array_classes(Klass* k) {
533 _global_klass_objects->append_if_missing(k);
534 if (k->is_array_klass()) {
535 // Add in the array classes too
536 ArrayKlass* ak = ArrayKlass::cast(k);
537 Klass* h = ak->higher_dimension();
538 if (h != NULL) {
539 h->array_klasses_do(collect_array_classes);
540 }
541 }
542 }
543
544 class CollectClassesClosure : public KlassClosure {
545 void do_klass(Klass* k) {
546 if (k->is_instance_klass() &&
547 SystemDictionaryShared::is_excluded_class(InstanceKlass::cast(k))) {
548 // Don't add to the _global_klass_objects
549 } else {
550 _global_klass_objects->append_if_missing(k);
551 }
552 if (k->is_array_klass()) {
553 // Add in the array classes too
554 ArrayKlass* ak = ArrayKlass::cast(k);
555 Klass* h = ak->higher_dimension();
556 if (h != NULL) {
557 h->array_klasses_do(collect_array_classes);
558 }
559 }
560 }
561 };
562
563 static void remove_unshareable_in_classes() {
564 for (int i = 0; i < _global_klass_objects->length(); i++) {
565 Klass* k = _global_klass_objects->at(i);
566 if (!k->is_objArray_klass()) {
567 // InstanceKlass and TypeArrayKlass will in turn call remove_unshareable_info
568 // on their array classes.
569 assert(k->is_instance_klass() || k->is_typeArray_klass(), "must be");
570 k->remove_unshareable_info();
571 }
572 }
573 }
574
575 static void remove_java_mirror_in_classes() {
576 for (int i = 0; i < _global_klass_objects->length(); i++) {
577 Klass* k = _global_klass_objects->at(i);
578 if (!k->is_objArray_klass()) {
579 // InstanceKlass and TypeArrayKlass will in turn call remove_unshareable_info
580 // on their array classes.
581 assert(k->is_instance_klass() || k->is_typeArray_klass(), "must be");
582 k->remove_java_mirror();
583 }
584 }
585 }
586
587 static void clear_basic_type_mirrors() {
588 assert(!HeapShared::is_heap_object_archiving_allowed(), "Sanity");
589 Universe::set_int_mirror(NULL);
590 Universe::set_float_mirror(NULL);
591 Universe::set_double_mirror(NULL);
592 Universe::set_byte_mirror(NULL);
593 Universe::set_bool_mirror(NULL);
594 Universe::set_char_mirror(NULL);
595 Universe::set_long_mirror(NULL);
596 Universe::set_short_mirror(NULL);
597 Universe::set_void_mirror(NULL);
598 }
599
600 static void rewrite_nofast_bytecode(Method* method) {
601 BytecodeStream bcs(method);
602 while (!bcs.is_last_bytecode()) {
603 Bytecodes::Code opcode = bcs.next();
604 switch (opcode) {
605 case Bytecodes::_getfield: *bcs.bcp() = Bytecodes::_nofast_getfield; break;
606 case Bytecodes::_putfield: *bcs.bcp() = Bytecodes::_nofast_putfield; break;
607 case Bytecodes::_aload_0: *bcs.bcp() = Bytecodes::_nofast_aload_0; break;
608 case Bytecodes::_iload: {
609 if (!bcs.is_wide()) {
610 *bcs.bcp() = Bytecodes::_nofast_iload;
611 }
612 break;
613 }
614 default: break;
615 }
616 }
617 }
618
619 // Walk all methods in the class list to ensure that they won't be modified at
620 // run time. This includes:
621 // [1] Rewrite all bytecodes as needed, so that the ConstMethod* will not be modified
622 // at run time by RewriteBytecodes/RewriteFrequentPairs
623 // [2] Assign a fingerprint, so one doesn't need to be assigned at run-time.
624 static void rewrite_nofast_bytecodes_and_calculate_fingerprints() {
625 for (int i = 0; i < _global_klass_objects->length(); i++) {
626 Klass* k = _global_klass_objects->at(i);
627 if (k->is_instance_klass()) {
628 InstanceKlass* ik = InstanceKlass::cast(k);
629 MetaspaceShared::rewrite_nofast_bytecodes_and_calculate_fingerprints(ik);
630 }
631 }
632 }
633
634 void MetaspaceShared::rewrite_nofast_bytecodes_and_calculate_fingerprints(InstanceKlass* ik) {
635 for (int i = 0; i < ik->methods()->length(); i++) {
636 Method* m = ik->methods()->at(i);
637 rewrite_nofast_bytecode(m);
638 Fingerprinter fp(m);
639 // The side effect of this call sets method's fingerprint field.
640 fp.fingerprint();
641 }
642 }
643
644 // Objects of the Metadata types (such as Klass and ConstantPool) have C++ vtables.
645 // (In GCC this is the field <Type>::_vptr, i.e., first word in the object.)
646 //
647 // Addresses of the vtables and the methods may be different across JVM runs,
648 // if libjvm.so is dynamically loaded at a different base address.
649 //
650 // To ensure that the Metadata objects in the CDS archive always have the correct vtable:
651 //
652 // + at dump time: we redirect the _vptr to point to our own vtables inside
653 // the CDS image
654 // + at run time: we clone the actual contents of the vtables from libjvm.so
655 // into our own tables.
656
657 // Currently, the archive contain ONLY the following types of objects that have C++ vtables.
658 #define CPP_VTABLE_PATCH_TYPES_DO(f) \
659 f(ConstantPool) \
660 f(InstanceKlass) \
661 f(InstanceClassLoaderKlass) \
662 f(InstanceMirrorKlass) \
663 f(InstanceRefKlass) \
664 f(Method) \
665 f(ObjArrayKlass) \
666 f(TypeArrayKlass)
667
668 class CppVtableInfo {
669 intptr_t _vtable_size;
670 intptr_t _cloned_vtable[1];
671 public:
672 static int num_slots(int vtable_size) {
673 return 1 + vtable_size; // Need to add the space occupied by _vtable_size;
674 }
675 int vtable_size() { return int(uintx(_vtable_size)); }
676 void set_vtable_size(int n) { _vtable_size = intptr_t(n); }
677 intptr_t* cloned_vtable() { return &_cloned_vtable[0]; }
678 void zero() { memset(_cloned_vtable, 0, sizeof(intptr_t) * vtable_size()); }
679 // Returns the address of the next CppVtableInfo that can be placed immediately after this CppVtableInfo
680 static size_t byte_size(int vtable_size) {
681 CppVtableInfo i;
682 return pointer_delta(&i._cloned_vtable[vtable_size], &i, sizeof(u1));
683 }
684 };
685
686 template <class T> class CppVtableCloner : public T {
687 static intptr_t* vtable_of(Metadata& m) {
688 return *((intptr_t**)&m);
689 }
690 static CppVtableInfo* _info;
691
692 static int get_vtable_length(const char* name);
693
694 public:
695 // Allocate and initialize the C++ vtable, starting from top, but do not go past end.
696 static intptr_t* allocate(const char* name);
697
698 // Clone the vtable to ...
699 static intptr_t* clone_vtable(const char* name, CppVtableInfo* info);
700
701 static void zero_vtable_clone() {
702 assert(DumpSharedSpaces, "dump-time only");
703 _info->zero();
704 }
705
706 // Switch the vtable pointer to point to the cloned vtable.
707 static void patch(Metadata* obj) {
708 assert(DumpSharedSpaces, "dump-time only");
709 *(void**)obj = (void*)(_info->cloned_vtable());
710 }
711
712 static bool is_valid_shared_object(const T* obj) {
713 intptr_t* vptr = *(intptr_t**)obj;
714 return vptr == _info->cloned_vtable();
715 }
716 };
717
718 template <class T> CppVtableInfo* CppVtableCloner<T>::_info = NULL;
719
720 template <class T>
721 intptr_t* CppVtableCloner<T>::allocate(const char* name) {
722 assert(is_aligned(_md_region.top(), sizeof(intptr_t)), "bad alignment");
723 int n = get_vtable_length(name);
724 _info = (CppVtableInfo*)_md_region.allocate(CppVtableInfo::byte_size(n), sizeof(intptr_t));
725 _info->set_vtable_size(n);
726
727 intptr_t* p = clone_vtable(name, _info);
728 assert((char*)p == _md_region.top(), "must be");
729
730 return _info->cloned_vtable();
731 }
732
733 template <class T>
734 intptr_t* CppVtableCloner<T>::clone_vtable(const char* name, CppVtableInfo* info) {
735 if (!DumpSharedSpaces) {
736 assert(_info == 0, "_info is initialized only at dump time");
737 _info = info; // Remember it -- it will be used by MetaspaceShared::is_valid_shared_method()
738 }
739 T tmp; // Allocate temporary dummy metadata object to get to the original vtable.
740 int n = info->vtable_size();
741 intptr_t* srcvtable = vtable_of(tmp);
742 intptr_t* dstvtable = info->cloned_vtable();
743
744 // We already checked (and, if necessary, adjusted n) when the vtables were allocated, so we are
745 // safe to do memcpy.
746 log_debug(cds, vtables)("Copying %3d vtable entries for %s", n, name);
747 memcpy(dstvtable, srcvtable, sizeof(intptr_t) * n);
748 return dstvtable + n;
749 }
750
751 // To determine the size of the vtable for each type, we use the following
752 // trick by declaring 2 subclasses:
753 //
754 // class CppVtableTesterA: public InstanceKlass {virtual int last_virtual_method() {return 1;} };
755 // class CppVtableTesterB: public InstanceKlass {virtual void* last_virtual_method() {return NULL}; };
756 //
757 // CppVtableTesterA and CppVtableTesterB's vtables have the following properties:
758 // - Their size (N+1) is exactly one more than the size of InstanceKlass's vtable (N)
759 // - The first N entries have are exactly the same as in InstanceKlass's vtable.
760 // - Their last entry is different.
761 //
762 // So to determine the value of N, we just walk CppVtableTesterA and CppVtableTesterB's tables
763 // and find the first entry that's different.
764 //
765 // This works on all C++ compilers supported by Oracle, but you may need to tweak it for more
766 // esoteric compilers.
767
768 template <class T> class CppVtableTesterB: public T {
769 public:
770 virtual int last_virtual_method() {return 1;}
771 };
772
773 template <class T> class CppVtableTesterA : public T {
774 public:
775 virtual void* last_virtual_method() {
776 // Make this different than CppVtableTesterB::last_virtual_method so the C++
777 // compiler/linker won't alias the two functions.
778 return NULL;
779 }
780 };
781
782 template <class T>
783 int CppVtableCloner<T>::get_vtable_length(const char* name) {
784 CppVtableTesterA<T> a;
785 CppVtableTesterB<T> b;
786
787 intptr_t* avtable = vtable_of(a);
788 intptr_t* bvtable = vtable_of(b);
789
790 // Start at slot 1, because slot 0 may be RTTI (on Solaris/Sparc)
791 int vtable_len = 1;
792 for (; ; vtable_len++) {
793 if (avtable[vtable_len] != bvtable[vtable_len]) {
794 break;
795 }
796 }
797 log_debug(cds, vtables)("Found %3d vtable entries for %s", vtable_len, name);
798
799 return vtable_len;
800 }
801
802 #define ALLOC_CPP_VTABLE_CLONE(c) \
803 _cloned_cpp_vtptrs[c##_Kind] = CppVtableCloner<c>::allocate(#c);
804
805 #define CLONE_CPP_VTABLE(c) \
806 p = CppVtableCloner<c>::clone_vtable(#c, (CppVtableInfo*)p);
807
808 #define ZERO_CPP_VTABLE(c) \
809 CppVtableCloner<c>::zero_vtable_clone();
810
811 //------------------------------ for DynamicDumpSharedSpaces - start
812 #define DECLARE_CLONED_VTABLE_KIND(c) c ## _Kind,
813
814 enum {
815 CPP_VTABLE_PATCH_TYPES_DO(DECLARE_CLONED_VTABLE_KIND)
816 _num_cloned_vtable_kinds
817 };
818
819 static intptr_t** _cloned_cpp_vtptrs = NULL;
820
821 void MetaspaceShared::serialize_cloned_cpp_vtptrs(SerializeClosure* soc) {
822 soc->do_ptr((void**)&_cloned_cpp_vtptrs);
823 }
824
825 intptr_t* MetaspaceShared::fix_cpp_vtable_for_dynamic_archive(MetaspaceObj::Type msotype, address obj) {
826 assert(DynamicDumpSharedSpaces, "must");
827 int kind = -1;
828 switch (msotype) {
829 case MetaspaceObj::SymbolType:
830 case MetaspaceObj::TypeArrayU1Type:
831 case MetaspaceObj::TypeArrayU2Type:
832 case MetaspaceObj::TypeArrayU4Type:
833 case MetaspaceObj::TypeArrayU8Type:
834 case MetaspaceObj::TypeArrayOtherType:
835 case MetaspaceObj::ConstMethodType:
836 case MetaspaceObj::ConstantPoolCacheType:
837 case MetaspaceObj::AnnotationsType:
838 case MetaspaceObj::MethodCountersType:
839 // These have no vtables.
840 break;
841 case MetaspaceObj::ClassType:
842 {
843 Klass* k = (Klass*)obj;
844 assert(k->is_klass(), "must be");
845 if (k->is_instance_klass()) {
846 kind = InstanceKlass_Kind;
847 } else {
848 assert(k->is_objArray_klass(),
849 "We shouldn't archive any other klasses in DynamicDumpSharedSpaces");
850 kind = ObjArrayKlass_Kind;
851 }
852 }
853 break;
854
855 case MetaspaceObj::MethodType:
856 {
857 Method* m = (Method*)obj;
858 assert(m->is_method(), "must be");
859 kind = Method_Kind;
860 }
861 break;
862
863 case MetaspaceObj::MethodDataType:
864 // We don't archive MethodData <-- should have been removed in removed_unsharable_info
865 ShouldNotReachHere();
866 break;
867
868 case MetaspaceObj::ConstantPoolType:
869 {
870 ConstantPool *cp = (ConstantPool*)obj;
871 assert(cp->is_constantPool(), "must be");
872 kind = ConstantPool_Kind;
873 }
874 break;
875
876 default:
877 ShouldNotReachHere();
878 }
879
880 if (kind >= 0) {
881 assert(kind < _num_cloned_vtable_kinds, "must be");
882 return _cloned_cpp_vtptrs[kind];
883 } else {
884 return NULL;
885 }
886 }
887
888 //------------------------------ for DynamicDumpSharedSpaces - end
889
890 // This can be called at both dump time and run time.
891 intptr_t* MetaspaceShared::clone_cpp_vtables(intptr_t* p) {
892 assert(DumpSharedSpaces || UseSharedSpaces, "sanity");
893 CPP_VTABLE_PATCH_TYPES_DO(CLONE_CPP_VTABLE);
894 return p;
895 }
896
897 void MetaspaceShared::zero_cpp_vtable_clones_for_writing() {
898 assert(DumpSharedSpaces, "dump-time only");
899 CPP_VTABLE_PATCH_TYPES_DO(ZERO_CPP_VTABLE);
900 }
901
902 // Allocate and initialize the C++ vtables, starting from top, but do not go past end.
903 void MetaspaceShared::allocate_cpp_vtable_clones() {
904 assert(DumpSharedSpaces, "dump-time only");
905 // Layout (each slot is a intptr_t):
906 // [number of slots in the first vtable = n1]
907 // [ <n1> slots for the first vtable]
908 // [number of slots in the first second = n2]
909 // [ <n2> slots for the second vtable]
910 // ...
911 // The order of the vtables is the same as the CPP_VTAB_PATCH_TYPES_DO macro.
912 CPP_VTABLE_PATCH_TYPES_DO(ALLOC_CPP_VTABLE_CLONE);
913 }
914
915 // Switch the vtable pointer to point to the cloned vtable. We assume the
916 // vtable pointer is in first slot in object.
917 void MetaspaceShared::patch_cpp_vtable_pointers() {
918 int n = _global_klass_objects->length();
919 for (int i = 0; i < n; i++) {
920 Klass* obj = _global_klass_objects->at(i);
921 if (obj->is_instance_klass()) {
922 InstanceKlass* ik = InstanceKlass::cast(obj);
923 if (ik->is_class_loader_instance_klass()) {
924 CppVtableCloner<InstanceClassLoaderKlass>::patch(ik);
925 } else if (ik->is_reference_instance_klass()) {
926 CppVtableCloner<InstanceRefKlass>::patch(ik);
927 } else if (ik->is_mirror_instance_klass()) {
928 CppVtableCloner<InstanceMirrorKlass>::patch(ik);
929 } else {
930 CppVtableCloner<InstanceKlass>::patch(ik);
931 }
932 ConstantPool* cp = ik->constants();
933 CppVtableCloner<ConstantPool>::patch(cp);
934 for (int j = 0; j < ik->methods()->length(); j++) {
935 Method* m = ik->methods()->at(j);
936 CppVtableCloner<Method>::patch(m);
937 assert(CppVtableCloner<Method>::is_valid_shared_object(m), "must be");
938 }
939 } else if (obj->is_objArray_klass()) {
940 CppVtableCloner<ObjArrayKlass>::patch(obj);
941 } else {
942 assert(obj->is_typeArray_klass(), "sanity");
943 CppVtableCloner<TypeArrayKlass>::patch(obj);
944 }
945 }
946 }
947
948 bool MetaspaceShared::is_valid_shared_method(const Method* m) {
949 assert(is_in_shared_metaspace(m), "must be");
950 return CppVtableCloner<Method>::is_valid_shared_object(m);
951 }
952
953 void WriteClosure::do_oop(oop* o) {
954 if (*o == NULL) {
955 _dump_region->append_intptr_t(0);
956 } else {
957 assert(HeapShared::is_heap_object_archiving_allowed(),
958 "Archiving heap object is not allowed");
959 _dump_region->append_intptr_t(
960 (intptr_t)CompressedOops::encode_not_null(*o));
961 }
962 }
963
964 void WriteClosure::do_region(u_char* start, size_t size) {
965 assert((intptr_t)start % sizeof(intptr_t) == 0, "bad alignment");
966 assert(size % sizeof(intptr_t) == 0, "bad size");
967 do_tag((int)size);
968 while (size > 0) {
969 _dump_region->append_intptr_t(*(intptr_t*)start);
970 start += sizeof(intptr_t);
971 size -= sizeof(intptr_t);
972 }
973 }
974
975 // This is for dumping detailed statistics for the allocations
976 // in the shared spaces.
977 class DumpAllocStats : public ResourceObj {
978 public:
979
980 // Here's poor man's enum inheritance
981 #define SHAREDSPACE_OBJ_TYPES_DO(f) \
982 METASPACE_OBJ_TYPES_DO(f) \
983 f(SymbolHashentry) \
984 f(SymbolBucket) \
985 f(StringHashentry) \
986 f(StringBucket) \
987 f(Other)
988
989 enum Type {
990 // Types are MetaspaceObj::ClassType, MetaspaceObj::SymbolType, etc
991 SHAREDSPACE_OBJ_TYPES_DO(METASPACE_OBJ_TYPE_DECLARE)
992 _number_of_types
993 };
994
995 static const char * type_name(Type type) {
996 switch(type) {
997 SHAREDSPACE_OBJ_TYPES_DO(METASPACE_OBJ_TYPE_NAME_CASE)
998 default:
999 ShouldNotReachHere();
1000 return NULL;
1001 }
1002 }
1003
1004 public:
1005 enum { RO = 0, RW = 1 };
1006
1007 int _counts[2][_number_of_types];
1008 int _bytes [2][_number_of_types];
1009
1010 DumpAllocStats() {
1011 memset(_counts, 0, sizeof(_counts));
1012 memset(_bytes, 0, sizeof(_bytes));
1013 };
1014
1015 void record(MetaspaceObj::Type type, int byte_size, bool read_only) {
1016 assert(int(type) >= 0 && type < MetaspaceObj::_number_of_types, "sanity");
1017 int which = (read_only) ? RO : RW;
1018 _counts[which][type] ++;
1019 _bytes [which][type] += byte_size;
1020 }
1021
1022 void record_other_type(int byte_size, bool read_only) {
1023 int which = (read_only) ? RO : RW;
1024 _bytes [which][OtherType] += byte_size;
1025 }
1026 void print_stats(int ro_all, int rw_all, int mc_all, int md_all);
1027 };
1028
1029 void DumpAllocStats::print_stats(int ro_all, int rw_all, int mc_all, int md_all) {
1030 // Calculate size of data that was not allocated by Metaspace::allocate()
1031 MetaspaceSharedStats *stats = MetaspaceShared::stats();
1032
1033 // symbols
1034 _counts[RO][SymbolHashentryType] = stats->symbol.hashentry_count;
1035 _bytes [RO][SymbolHashentryType] = stats->symbol.hashentry_bytes;
1036
1037 _counts[RO][SymbolBucketType] = stats->symbol.bucket_count;
1038 _bytes [RO][SymbolBucketType] = stats->symbol.bucket_bytes;
1039
1040 // strings
1041 _counts[RO][StringHashentryType] = stats->string.hashentry_count;
1042 _bytes [RO][StringHashentryType] = stats->string.hashentry_bytes;
1043
1044 _counts[RO][StringBucketType] = stats->string.bucket_count;
1045 _bytes [RO][StringBucketType] = stats->string.bucket_bytes;
1046
1047 // TODO: count things like dictionary, vtable, etc
1048 _bytes[RW][OtherType] += mc_all + md_all;
1049 rw_all += mc_all + md_all; // mc/md are mapped Read/Write
1050
1051 // prevent divide-by-zero
1052 if (ro_all < 1) {
1053 ro_all = 1;
1054 }
1055 if (rw_all < 1) {
1056 rw_all = 1;
1057 }
1058
1059 int all_ro_count = 0;
1060 int all_ro_bytes = 0;
1061 int all_rw_count = 0;
1062 int all_rw_bytes = 0;
1063
1064 // To make fmt_stats be a syntactic constant (for format warnings), use #define.
1065 #define fmt_stats "%-20s: %8d %10d %5.1f | %8d %10d %5.1f | %8d %10d %5.1f"
1066 const char *sep = "--------------------+---------------------------+---------------------------+--------------------------";
1067 const char *hdr = " ro_cnt ro_bytes % | rw_cnt rw_bytes % | all_cnt all_bytes %";
1068
1069 LogMessage(cds) msg;
1070
1071 msg.info("Detailed metadata info (excluding st regions; rw stats include md/mc regions):");
1072 msg.info("%s", hdr);
1073 msg.info("%s", sep);
1074 for (int type = 0; type < int(_number_of_types); type ++) {
1075 const char *name = type_name((Type)type);
1076 int ro_count = _counts[RO][type];
1077 int ro_bytes = _bytes [RO][type];
1078 int rw_count = _counts[RW][type];
1079 int rw_bytes = _bytes [RW][type];
1080 int count = ro_count + rw_count;
1081 int bytes = ro_bytes + rw_bytes;
1082
1083 double ro_perc = percent_of(ro_bytes, ro_all);
1084 double rw_perc = percent_of(rw_bytes, rw_all);
1085 double perc = percent_of(bytes, ro_all + rw_all);
1086
1087 msg.info(fmt_stats, name,
1088 ro_count, ro_bytes, ro_perc,
1089 rw_count, rw_bytes, rw_perc,
1090 count, bytes, perc);
1091
1092 all_ro_count += ro_count;
1093 all_ro_bytes += ro_bytes;
1094 all_rw_count += rw_count;
1095 all_rw_bytes += rw_bytes;
1096 }
1097
1098 int all_count = all_ro_count + all_rw_count;
1099 int all_bytes = all_ro_bytes + all_rw_bytes;
1100
1101 double all_ro_perc = percent_of(all_ro_bytes, ro_all);
1102 double all_rw_perc = percent_of(all_rw_bytes, rw_all);
1103 double all_perc = percent_of(all_bytes, ro_all + rw_all);
1104
1105 msg.info("%s", sep);
1106 msg.info(fmt_stats, "Total",
1107 all_ro_count, all_ro_bytes, all_ro_perc,
1108 all_rw_count, all_rw_bytes, all_rw_perc,
1109 all_count, all_bytes, all_perc);
1110
1111 assert(all_ro_bytes == ro_all, "everything should have been counted");
1112 assert(all_rw_bytes == rw_all, "everything should have been counted");
1113
1114 #undef fmt_stats
1115 }
1116
1117 // Populate the shared space.
1118
1119 class VM_PopulateDumpSharedSpace: public VM_Operation {
1120 private:
1121 GrowableArray<MemRegion> *_closed_archive_heap_regions;
1122 GrowableArray<MemRegion> *_open_archive_heap_regions;
1123
1124 GrowableArray<ArchiveHeapOopmapInfo> *_closed_archive_heap_oopmaps;
1125 GrowableArray<ArchiveHeapOopmapInfo> *_open_archive_heap_oopmaps;
1126
1127 void dump_java_heap_objects() NOT_CDS_JAVA_HEAP_RETURN;
1128 void dump_archive_heap_oopmaps() NOT_CDS_JAVA_HEAP_RETURN;
1129 void dump_archive_heap_oopmaps(GrowableArray<MemRegion>* regions,
1130 GrowableArray<ArchiveHeapOopmapInfo>* oopmaps);
1131 void dump_symbols();
1132 char* dump_read_only_tables();
1133 void print_region_stats();
1134 void print_heap_region_stats(GrowableArray<MemRegion> *heap_mem,
1135 const char *name, const size_t total_size);
1136 public:
1137
1138 VMOp_Type type() const { return VMOp_PopulateDumpSharedSpace; }
1139 void doit(); // outline because gdb sucks
1140 static void write_region(FileMapInfo* mapinfo, int region_idx, DumpRegion* dump_region, bool read_only, bool allow_exec) {
1141 mapinfo->write_region(region_idx, dump_region->base(), dump_region->used(), read_only, allow_exec);
1142 }
1143 bool allow_nested_vm_operations() const { return true; }
1144 }; // class VM_PopulateDumpSharedSpace
1145
1146 class SortedSymbolClosure: public SymbolClosure {
1147 GrowableArray<Symbol*> _symbols;
1148 virtual void do_symbol(Symbol** sym) {
1149 assert((*sym)->is_permanent(), "archived symbols must be permanent");
1150 _symbols.append(*sym);
1151 }
1152 static int compare_symbols_by_address(Symbol** a, Symbol** b) {
1153 if (a[0] < b[0]) {
1154 return -1;
1155 } else if (a[0] == b[0]) {
1156 return 0;
1157 } else {
1158 return 1;
1159 }
1160 }
1161
1162 public:
1163 SortedSymbolClosure() {
1164 SymbolTable::symbols_do(this);
1165 _symbols.sort(compare_symbols_by_address);
1166 }
1167 GrowableArray<Symbol*>* get_sorted_symbols() {
1168 return &_symbols;
1169 }
1170 };
1171
1172 // ArchiveCompactor --
1173 //
1174 // This class is the central piece of shared archive compaction -- all metaspace data are
1175 // initially allocated outside of the shared regions. ArchiveCompactor copies the
1176 // metaspace data into their final location in the shared regions.
1177
1178 class ArchiveCompactor : AllStatic {
1179 static const int INITIAL_TABLE_SIZE = 8087;
1180 static const int MAX_TABLE_SIZE = 1000000;
1181
1182 static DumpAllocStats* _alloc_stats;
1183 static SortedSymbolClosure* _ssc;
1184
1185 typedef KVHashtable<address, address, mtInternal> RelocationTable;
1186 static RelocationTable* _new_loc_table;
1187
1188 public:
1189 static void initialize() {
1190 _alloc_stats = new(ResourceObj::C_HEAP, mtInternal)DumpAllocStats;
1191 _new_loc_table = new RelocationTable(INITIAL_TABLE_SIZE);
1192 }
1193 static DumpAllocStats* alloc_stats() {
1194 return _alloc_stats;
1195 }
1196
1197 // Use this when you allocate space with MetaspaceShare::read_only_space_alloc()
1198 // outside of ArchiveCompactor::allocate(). These are usually for misc tables
1199 // that are allocated in the RO space.
1200 class OtherROAllocMark {
1201 char* _oldtop;
1202 public:
1203 OtherROAllocMark() {
1204 _oldtop = _ro_region.top();
1205 }
1206 ~OtherROAllocMark() {
1207 char* newtop = _ro_region.top();
1208 ArchiveCompactor::alloc_stats()->record_other_type(int(newtop - _oldtop), true);
1209 }
1210 };
1211
1212 static void allocate(MetaspaceClosure::Ref* ref, bool read_only) {
1213 address obj = ref->obj();
1214 int bytes = ref->size() * BytesPerWord;
1215 char* p;
1216 size_t alignment = BytesPerWord;
1217 char* oldtop;
1218 char* newtop;
1219
1220 if (read_only) {
1221 oldtop = _ro_region.top();
1222 p = _ro_region.allocate(bytes, alignment);
1223 newtop = _ro_region.top();
1224 } else {
1225 oldtop = _rw_region.top();
1226 if (ref->msotype() == MetaspaceObj::ClassType) {
1227 // Save a pointer immediate in front of an InstanceKlass, so
1228 // we can do a quick lookup from InstanceKlass* -> RunTimeSharedClassInfo*
1229 // without building another hashtable. See RunTimeSharedClassInfo::get_for()
1230 // in systemDictionaryShared.cpp.
1231 Klass* klass = (Klass*)obj;
1232 if (klass->is_instance_klass()) {
1233 SystemDictionaryShared::validate_before_archiving(InstanceKlass::cast(klass));
1234 _rw_region.allocate(sizeof(address), BytesPerWord);
1235 }
1236 }
1237 p = _rw_region.allocate(bytes, alignment);
1238 newtop = _rw_region.top();
1239 }
1240 memcpy(p, obj, bytes);
1241 assert(_new_loc_table->lookup(obj) == NULL, "each object can be relocated at most once");
1242 _new_loc_table->add(obj, (address)p);
1243 log_trace(cds)("Copy: " PTR_FORMAT " ==> " PTR_FORMAT " %d", p2i(obj), p2i(p), bytes);
1244 if (_new_loc_table->maybe_grow(MAX_TABLE_SIZE)) {
1245 log_info(cds, hashtables)("Expanded _new_loc_table to %d", _new_loc_table->table_size());
1246 }
1247 _alloc_stats->record(ref->msotype(), int(newtop - oldtop), read_only);
1248 }
1249
1250 static address get_new_loc(MetaspaceClosure::Ref* ref) {
1251 address* pp = _new_loc_table->lookup(ref->obj());
1252 assert(pp != NULL, "must be");
1253 return *pp;
1254 }
1255
1256 private:
1257 // Makes a shallow copy of visited MetaspaceObj's
1258 class ShallowCopier: public UniqueMetaspaceClosure {
1259 bool _read_only;
1260 public:
1261 ShallowCopier(bool read_only) : _read_only(read_only) {}
1262
1263 virtual bool do_unique_ref(Ref* ref, bool read_only) {
1264 if (read_only == _read_only) {
1265 allocate(ref, read_only);
1266 }
1267 return true; // recurse into ref.obj()
1268 }
1269 };
1270
1271 // Relocate embedded pointers within a MetaspaceObj's shallow copy
1272 class ShallowCopyEmbeddedRefRelocator: public UniqueMetaspaceClosure {
1273 public:
1274 virtual bool do_unique_ref(Ref* ref, bool read_only) {
1275 address new_loc = get_new_loc(ref);
1276 RefRelocator refer;
1277 ref->metaspace_pointers_do_at(&refer, new_loc);
1278 return true; // recurse into ref.obj()
1279 }
1280 };
1281
1282 // Relocate a reference to point to its shallow copy
1283 class RefRelocator: public MetaspaceClosure {
1284 public:
1285 virtual bool do_ref(Ref* ref, bool read_only) {
1286 if (ref->not_null()) {
1287 ref->update(get_new_loc(ref));
1288 }
1289 return false; // Do not recurse.
1290 }
1291 };
1292
1293 #ifdef ASSERT
1294 class IsRefInArchiveChecker: public MetaspaceClosure {
1295 public:
1296 virtual bool do_ref(Ref* ref, bool read_only) {
1297 if (ref->not_null()) {
1298 char* obj = (char*)ref->obj();
1299 assert(_ro_region.contains(obj) || _rw_region.contains(obj),
1300 "must be relocated to point to CDS archive");
1301 }
1302 return false; // Do not recurse.
1303 }
1304 };
1305 #endif
1306
1307 public:
1308 static void copy_and_compact() {
1309 ResourceMark rm;
1310 SortedSymbolClosure the_ssc; // StackObj
1311 _ssc = &the_ssc;
1312
1313 tty->print_cr("Scanning all metaspace objects ... ");
1314 {
1315 // allocate and shallow-copy RW objects, immediately following the MC region
1316 tty->print_cr("Allocating RW objects ... ");
1317 _mc_region.pack(&_rw_region);
1318
1319 ResourceMark rm;
1320 ShallowCopier rw_copier(false);
1321 iterate_roots(&rw_copier);
1322 }
1323 {
1324 // allocate and shallow-copy of RO object, immediately following the RW region
1325 tty->print_cr("Allocating RO objects ... ");
1326 _rw_region.pack(&_ro_region);
1327
1328 ResourceMark rm;
1329 ShallowCopier ro_copier(true);
1330 iterate_roots(&ro_copier);
1331 }
1332 {
1333 tty->print_cr("Relocating embedded pointers ... ");
1334 ResourceMark rm;
1335 ShallowCopyEmbeddedRefRelocator emb_reloc;
1336 iterate_roots(&emb_reloc);
1337 }
1338 {
1339 tty->print_cr("Relocating external roots ... ");
1340 ResourceMark rm;
1341 RefRelocator ext_reloc;
1342 iterate_roots(&ext_reloc);
1343 }
1344
1345 #ifdef ASSERT
1346 {
1347 tty->print_cr("Verifying external roots ... ");
1348 ResourceMark rm;
1349 IsRefInArchiveChecker checker;
1350 iterate_roots(&checker);
1351 }
1352 #endif
1353
1354
1355 // cleanup
1356 _ssc = NULL;
1357 }
1358
1359 // We must relocate the System::_well_known_klasses only after we have copied the
1360 // java objects in during dump_java_heap_objects(): during the object copy, we operate on
1361 // old objects which assert that their klass is the original klass.
1362 static void relocate_well_known_klasses() {
1363 {
1364 tty->print_cr("Relocating SystemDictionary::_well_known_klasses[] ... ");
1365 ResourceMark rm;
1366 RefRelocator ext_reloc;
1367 SystemDictionary::well_known_klasses_do(&ext_reloc);
1368 }
1369 // NOTE: after this point, we shouldn't have any globals that can reach the old
1370 // objects.
1371
1372 // We cannot use any of the objects in the heap anymore (except for the
1373 // shared strings) because their headers no longer point to valid Klasses.
1374 }
1375
1376 static void iterate_roots(MetaspaceClosure* it) {
1377 GrowableArray<Symbol*>* symbols = _ssc->get_sorted_symbols();
1378 for (int i=0; i<symbols->length(); i++) {
1379 it->push(symbols->adr_at(i));
1380 }
1381 if (_global_klass_objects != NULL) {
1382 // Need to fix up the pointers
1383 for (int i = 0; i < _global_klass_objects->length(); i++) {
1384 // NOTE -- this requires that the vtable is NOT yet patched, or else we are hosed.
1385 it->push(_global_klass_objects->adr_at(i));
1386 }
1387 }
1388 FileMapInfo::metaspace_pointers_do(it);
1389 SystemDictionaryShared::dumptime_classes_do(it);
1390 Universe::metaspace_pointers_do(it);
1391 SymbolTable::metaspace_pointers_do(it);
1392 vmSymbols::metaspace_pointers_do(it);
1393
1394 it->finish();
1395 }
1396
1397 static Klass* get_relocated_klass(Klass* orig_klass) {
1398 assert(DumpSharedSpaces, "dump time only");
1399 address* pp = _new_loc_table->lookup((address)orig_klass);
1400 assert(pp != NULL, "must be");
1401 Klass* klass = (Klass*)(*pp);
1402 assert(klass->is_klass(), "must be");
1403 return klass;
1404 }
1405 };
1406
1407 DumpAllocStats* ArchiveCompactor::_alloc_stats;
1408 SortedSymbolClosure* ArchiveCompactor::_ssc;
1409 ArchiveCompactor::RelocationTable* ArchiveCompactor::_new_loc_table;
1410
1411 void VM_PopulateDumpSharedSpace::dump_symbols() {
1412 tty->print_cr("Dumping symbol table ...");
1413
1414 NOT_PRODUCT(SymbolTable::verify());
1415 SymbolTable::write_to_archive();
1416 }
1417
1418 char* VM_PopulateDumpSharedSpace::dump_read_only_tables() {
1419 ArchiveCompactor::OtherROAllocMark mark;
1420
1421 tty->print("Removing java_mirror ... ");
1422 if (!HeapShared::is_heap_object_archiving_allowed()) {
1423 clear_basic_type_mirrors();
1424 }
1425 remove_java_mirror_in_classes();
1426 tty->print_cr("done. ");
1427
1428 SystemDictionaryShared::write_to_archive();
1429
1430 size_t vtptrs_bytes = _num_cloned_vtable_kinds * sizeof(intptr_t*);
1431 _cloned_cpp_vtptrs = (intptr_t**)_ro_region.allocate(vtptrs_bytes, sizeof(intptr_t*));
1432
1433 // Write the other data to the output array.
1434 char* start = _ro_region.top();
1435 WriteClosure wc(&_ro_region);
1436 MetaspaceShared::serialize(&wc);
1437
1438 // Write the bitmaps for patching the archive heap regions
1439 dump_archive_heap_oopmaps();
1440
1441 return start;
1442 }
1443
1444 void VM_PopulateDumpSharedSpace::doit() {
1445 // We should no longer allocate anything from the metaspace, so that:
1446 //
1447 // (1) Metaspace::allocate might trigger GC if we have run out of
1448 // committed metaspace, but we can't GC because we're running
1449 // in the VM thread.
1450 // (2) ArchiveCompactor needs to work with a stable set of MetaspaceObjs.
1451 Metaspace::freeze();
1452 DEBUG_ONLY(SystemDictionaryShared::NoClassLoadingMark nclm);
1453
1454 Thread* THREAD = VMThread::vm_thread();
1455
1456 FileMapInfo::check_nonempty_dir_in_shared_path_table();
1457
1458 NOT_PRODUCT(SystemDictionary::verify();)
1459 // The following guarantee is meant to ensure that no loader constraints
1460 // exist yet, since the constraints table is not shared. This becomes
1461 // more important now that we don't re-initialize vtables/itables for
1462 // shared classes at runtime, where constraints were previously created.
1463 guarantee(SystemDictionary::constraints()->number_of_entries() == 0,
1464 "loader constraints are not saved");
1465 guarantee(SystemDictionary::placeholders()->number_of_entries() == 0,
1466 "placeholders are not saved");
1467
1468 // At this point, many classes have been loaded.
1469 // Gather systemDictionary classes in a global array and do everything to
1470 // that so we don't have to walk the SystemDictionary again.
1471 SystemDictionaryShared::check_excluded_classes();
1472 _global_klass_objects = new GrowableArray<Klass*>(1000);
1473 CollectClassesClosure collect_classes;
1474 ClassLoaderDataGraph::loaded_classes_do(&collect_classes);
1475
1476 tty->print_cr("Number of classes %d", _global_klass_objects->length());
1477 {
1478 int num_type_array = 0, num_obj_array = 0, num_inst = 0;
1479 for (int i = 0; i < _global_klass_objects->length(); i++) {
1480 Klass* k = _global_klass_objects->at(i);
1481 if (k->is_instance_klass()) {
1482 num_inst ++;
1483 } else if (k->is_objArray_klass()) {
1484 num_obj_array ++;
1485 } else {
1486 assert(k->is_typeArray_klass(), "sanity");
1487 num_type_array ++;
1488 }
1489 }
1490 tty->print_cr(" instance classes = %5d", num_inst);
1491 tty->print_cr(" obj array classes = %5d", num_obj_array);
1492 tty->print_cr(" type array classes = %5d", num_type_array);
1493 }
1494
1495 // Ensure the ConstMethods won't be modified at run-time
1496 tty->print("Updating ConstMethods ... ");
1497 rewrite_nofast_bytecodes_and_calculate_fingerprints();
1498 tty->print_cr("done. ");
1499
1500 // Remove all references outside the metadata
1501 tty->print("Removing unshareable information ... ");
1502 remove_unshareable_in_classes();
1503 tty->print_cr("done. ");
1504
1505 ArchiveCompactor::initialize();
1506 ArchiveCompactor::copy_and_compact();
1507
1508 dump_symbols();
1509
1510 // Dump supported java heap objects
1511 _closed_archive_heap_regions = NULL;
1512 _open_archive_heap_regions = NULL;
1513 dump_java_heap_objects();
1514
1515 ArchiveCompactor::relocate_well_known_klasses();
1516
1517 char* serialized_data_start = dump_read_only_tables();
1518 _ro_region.pack(&_md_region);
1519
1520 char* vtbl_list = _md_region.top();
1521 MetaspaceShared::allocate_cpp_vtable_clones();
1522 _md_region.pack();
1523
1524 // The 4 core spaces are allocated consecutively mc->rw->ro->md, so there total size
1525 // is just the spaces between the two ends.
1526 size_t core_spaces_size = _md_region.end() - _mc_region.base();
1527 assert(core_spaces_size == (size_t)align_up(core_spaces_size, Metaspace::reserve_alignment()),
1528 "should already be aligned");
1529
1530 // During patching, some virtual methods may be called, so at this point
1531 // the vtables must contain valid methods (as filled in by CppVtableCloner::allocate).
1532 MetaspaceShared::patch_cpp_vtable_pointers();
1533
1534 // The vtable clones contain addresses of the current process.
1535 // We don't want to write these addresses into the archive.
1536 MetaspaceShared::zero_cpp_vtable_clones_for_writing();
1537
1538 // Create and write the archive file that maps the shared spaces.
1539
1540 FileMapInfo* mapinfo = new FileMapInfo(true);
1541 mapinfo->populate_header(os::vm_allocation_granularity());
1542 mapinfo->set_serialized_data_start(serialized_data_start);
1543 mapinfo->set_misc_data_patching_start(vtbl_list);
1544 mapinfo->set_i2i_entry_code_buffers(MetaspaceShared::i2i_entry_code_buffers(),
1545 MetaspaceShared::i2i_entry_code_buffers_size());
1546 mapinfo->set_core_spaces_size(core_spaces_size);
1547 mapinfo->open_for_write();
1548
1549 // NOTE: md contains the trampoline code for method entries, which are patched at run time,
1550 // so it needs to be read/write.
1551 write_region(mapinfo, MetaspaceShared::mc, &_mc_region, /*read_only=*/false,/*allow_exec=*/true);
1552 write_region(mapinfo, MetaspaceShared::rw, &_rw_region, /*read_only=*/false,/*allow_exec=*/false);
1553 write_region(mapinfo, MetaspaceShared::ro, &_ro_region, /*read_only=*/true, /*allow_exec=*/false);
1554 write_region(mapinfo, MetaspaceShared::md, &_md_region, /*read_only=*/false,/*allow_exec=*/false);
1555
1556 _total_closed_archive_region_size = mapinfo->write_archive_heap_regions(
1557 _closed_archive_heap_regions,
1558 _closed_archive_heap_oopmaps,
1559 MetaspaceShared::first_closed_archive_heap_region,
1560 MetaspaceShared::max_closed_archive_heap_region);
1561 _total_open_archive_region_size = mapinfo->write_archive_heap_regions(
1562 _open_archive_heap_regions,
1563 _open_archive_heap_oopmaps,
1564 MetaspaceShared::first_open_archive_heap_region,
1565 MetaspaceShared::max_open_archive_heap_region);
1566
1567 mapinfo->set_header_crc(mapinfo->compute_header_crc());
1568 mapinfo->write_header();
1569 mapinfo->close();
1570
1571 // Restore the vtable in case we invoke any virtual methods.
1572 MetaspaceShared::clone_cpp_vtables((intptr_t*)vtbl_list);
1573
1574 print_region_stats();
1575
1576 if (log_is_enabled(Info, cds)) {
1577 ArchiveCompactor::alloc_stats()->print_stats(int(_ro_region.used()), int(_rw_region.used()),
1578 int(_mc_region.used()), int(_md_region.used()));
1579 }
1580
1581 if (PrintSystemDictionaryAtExit) {
1582 SystemDictionary::print();
1583 }
1584
1585 if (AllowArchivingWithJavaAgent) {
1586 warning("This archive was created with AllowArchivingWithJavaAgent. It should be used "
1587 "for testing purposes only and should not be used in a production environment");
1588 }
1589
1590 // There may be other pending VM operations that operate on the InstanceKlasses,
1591 // which will fail because InstanceKlasses::remove_unshareable_info()
1592 // has been called. Forget these operations and exit the VM directly.
1593 vm_direct_exit(0);
1594 }
1595
1596 void VM_PopulateDumpSharedSpace::print_region_stats() {
1597 // Print statistics of all the regions
1598 const size_t total_reserved = _ro_region.reserved() + _rw_region.reserved() +
1599 _mc_region.reserved() + _md_region.reserved() +
1600 _total_closed_archive_region_size +
1601 _total_open_archive_region_size;
1602 const size_t total_bytes = _ro_region.used() + _rw_region.used() +
1603 _mc_region.used() + _md_region.used() +
1604 _total_closed_archive_region_size +
1605 _total_open_archive_region_size;
1606 const double total_u_perc = percent_of(total_bytes, total_reserved);
1607
1608 _mc_region.print(total_reserved);
1609 _rw_region.print(total_reserved);
1610 _ro_region.print(total_reserved);
1611 _md_region.print(total_reserved);
1612 print_heap_region_stats(_closed_archive_heap_regions, "ca", total_reserved);
1613 print_heap_region_stats(_open_archive_heap_regions, "oa", total_reserved);
1614
1615 tty->print_cr("total : " SIZE_FORMAT_W(9) " [100.0%% of total] out of " SIZE_FORMAT_W(9) " bytes [%5.1f%% used]",
1616 total_bytes, total_reserved, total_u_perc);
1617 }
1618
1619 void VM_PopulateDumpSharedSpace::print_heap_region_stats(GrowableArray<MemRegion> *heap_mem,
1620 const char *name, const size_t total_size) {
1621 int arr_len = heap_mem == NULL ? 0 : heap_mem->length();
1622 for (int i = 0; i < arr_len; i++) {
1623 char* start = (char*)heap_mem->at(i).start();
1624 size_t size = heap_mem->at(i).byte_size();
1625 char* top = start + size;
1626 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,
1627 name, i, size, size/double(total_size)*100.0, size, p2i(start));
1628
1629 }
1630 }
1631
1632 // Update a Java object to point its Klass* to the new location after
1633 // shared archive has been compacted.
1634 void MetaspaceShared::relocate_klass_ptr(oop o) {
1635 assert(DumpSharedSpaces, "sanity");
1636 Klass* k = ArchiveCompactor::get_relocated_klass(o->klass());
1637 o->set_klass(k);
1638 }
1639
1640 Klass* MetaspaceShared::get_relocated_klass(Klass *k) {
1641 assert(DumpSharedSpaces, "sanity");
1642 return ArchiveCompactor::get_relocated_klass(k);
1643 }
1644
1645 class LinkSharedClassesClosure : public KlassClosure {
1646 Thread* THREAD;
1647 bool _made_progress;
1648 public:
1649 LinkSharedClassesClosure(Thread* thread) : THREAD(thread), _made_progress(false) {}
1650
1651 void reset() { _made_progress = false; }
1652 bool made_progress() const { return _made_progress; }
1653
1654 void do_klass(Klass* k) {
1655 if (k->is_instance_klass()) {
1656 InstanceKlass* ik = InstanceKlass::cast(k);
1657 // Link the class to cause the bytecodes to be rewritten and the
1658 // cpcache to be created. Class verification is done according
1659 // to -Xverify setting.
1660 _made_progress |= MetaspaceShared::try_link_class(ik, THREAD);
1661 guarantee(!HAS_PENDING_EXCEPTION, "exception in link_class");
1662
1663 ik->constants()->resolve_class_constants(THREAD);
1664 }
1665 }
1666 };
1667
1668 class CheckSharedClassesClosure : public KlassClosure {
1669 bool _made_progress;
1670 public:
1671 CheckSharedClassesClosure() : _made_progress(false) {}
1672
1673 void reset() { _made_progress = false; }
1674 bool made_progress() const { return _made_progress; }
1675 void do_klass(Klass* k) {
1676 if (k->is_instance_klass() && InstanceKlass::cast(k)->check_sharing_error_state()) {
1677 _made_progress = true;
1678 }
1679 }
1680 };
1681
1682 void MetaspaceShared::link_and_cleanup_shared_classes(TRAPS) {
1683 // We need to iterate because verification may cause additional classes
1684 // to be loaded.
1685 LinkSharedClassesClosure link_closure(THREAD);
1686 do {
1687 link_closure.reset();
1688 ClassLoaderDataGraph::unlocked_loaded_classes_do(&link_closure);
1689 guarantee(!HAS_PENDING_EXCEPTION, "exception in link_class");
1690 } while (link_closure.made_progress());
1691
1692 if (_has_error_classes) {
1693 // Mark all classes whose super class or interfaces failed verification.
1694 CheckSharedClassesClosure check_closure;
1695 do {
1696 // Not completely sure if we need to do this iteratively. Anyway,
1697 // we should come here only if there are unverifiable classes, which
1698 // shouldn't happen in normal cases. So better safe than sorry.
1699 check_closure.reset();
1700 ClassLoaderDataGraph::unlocked_loaded_classes_do(&check_closure);
1701 } while (check_closure.made_progress());
1702 }
1703 }
1704
1705 void MetaspaceShared::prepare_for_dumping() {
1706 Arguments::check_unsupported_dumping_properties();
1707 ClassLoader::initialize_shared_path();
1708 }
1709
1710 // Preload classes from a list, populate the shared spaces and dump to a
1711 // file.
1712 void MetaspaceShared::preload_and_dump(TRAPS) {
1713 { TraceTime timer("Dump Shared Spaces", TRACETIME_LOG(Info, startuptime));
1714 ResourceMark rm;
1715 char class_list_path_str[JVM_MAXPATHLEN];
1716 // Preload classes to be shared.
1717 const char* class_list_path;
1718 if (SharedClassListFile == NULL) {
1719 // Construct the path to the class list (in jre/lib)
1720 // Walk up two directories from the location of the VM and
1721 // optionally tack on "lib" (depending on platform)
1722 os::jvm_path(class_list_path_str, sizeof(class_list_path_str));
1723 for (int i = 0; i < 3; i++) {
1724 char *end = strrchr(class_list_path_str, *os::file_separator());
1725 if (end != NULL) *end = '\0';
1726 }
1727 int class_list_path_len = (int)strlen(class_list_path_str);
1728 if (class_list_path_len >= 3) {
1729 if (strcmp(class_list_path_str + class_list_path_len - 3, "lib") != 0) {
1730 if (class_list_path_len < JVM_MAXPATHLEN - 4) {
1731 jio_snprintf(class_list_path_str + class_list_path_len,
1732 sizeof(class_list_path_str) - class_list_path_len,
1733 "%slib", os::file_separator());
1734 class_list_path_len += 4;
1735 }
1736 }
1737 }
1738 if (class_list_path_len < JVM_MAXPATHLEN - 10) {
1739 jio_snprintf(class_list_path_str + class_list_path_len,
1740 sizeof(class_list_path_str) - class_list_path_len,
1741 "%sclasslist", os::file_separator());
1742 }
1743 class_list_path = class_list_path_str;
1744 } else {
1745 class_list_path = SharedClassListFile;
1746 }
1747
1748 tty->print_cr("Loading classes to share ...");
1749 _has_error_classes = false;
1750 int class_count = preload_classes(class_list_path, THREAD);
1751 if (ExtraSharedClassListFile) {
1752 class_count += preload_classes(ExtraSharedClassListFile, THREAD);
1753 }
1754 tty->print_cr("Loading classes to share: done.");
1755
1756 log_info(cds)("Shared spaces: preloaded %d classes", class_count);
1757
1758 if (SharedArchiveConfigFile) {
1759 tty->print_cr("Reading extra data from %s ...", SharedArchiveConfigFile);
1760 read_extra_data(SharedArchiveConfigFile, THREAD);
1761 }
1762 tty->print_cr("Reading extra data: done.");
1763
1764 HeapShared::init_subgraph_entry_fields(THREAD);
1765
1766 // Rewrite and link classes
1767 tty->print_cr("Rewriting and linking classes ...");
1768
1769 // Link any classes which got missed. This would happen if we have loaded classes that
1770 // were not explicitly specified in the classlist. E.g., if an interface implemented by class K
1771 // fails verification, all other interfaces that were not specified in the classlist but
1772 // are implemented by K are not verified.
1773 link_and_cleanup_shared_classes(CATCH);
1774 tty->print_cr("Rewriting and linking classes: done");
1775
1776 if (HeapShared::is_heap_object_archiving_allowed()) {
1777 // Avoid fragmentation while archiving heap objects.
1778 Universe::heap()->soft_ref_policy()->set_should_clear_all_soft_refs(true);
1779 Universe::heap()->collect(GCCause::_archive_time_gc);
1780 Universe::heap()->soft_ref_policy()->set_should_clear_all_soft_refs(false);
1781 }
1782
1783 VM_PopulateDumpSharedSpace op;
1784 VMThread::execute(&op);
1785 }
1786 }
1787
1788
1789 int MetaspaceShared::preload_classes(const char* class_list_path, TRAPS) {
1790 ClassListParser parser(class_list_path);
1791 int class_count = 0;
1792
1793 while (parser.parse_one_line()) {
1794 Klass* klass = parser.load_current_class(THREAD);
1795 if (HAS_PENDING_EXCEPTION) {
1796 if (klass == NULL &&
1797 (PENDING_EXCEPTION->klass()->name() == vmSymbols::java_lang_ClassNotFoundException())) {
1798 // print a warning only when the pending exception is class not found
1799 log_warning(cds)("Preload Warning: Cannot find %s", parser.current_class_name());
1800 }
1801 CLEAR_PENDING_EXCEPTION;
1802 }
1803 if (klass != NULL) {
1804 if (log_is_enabled(Trace, cds)) {
1805 ResourceMark rm;
1806 log_trace(cds)("Shared spaces preloaded: %s", klass->external_name());
1807 }
1808
1809 if (klass->is_instance_klass()) {
1810 InstanceKlass* ik = InstanceKlass::cast(klass);
1811
1812 // Link the class to cause the bytecodes to be rewritten and the
1813 // cpcache to be created. The linking is done as soon as classes
1814 // are loaded in order that the related data structures (klass and
1815 // cpCache) are located together.
1816 try_link_class(ik, THREAD);
1817 guarantee(!HAS_PENDING_EXCEPTION, "exception in link_class");
1818 }
1819
1820 class_count++;
1821 }
1822 }
1823
1824 return class_count;
1825 }
1826
1827 // Returns true if the class's status has changed
1828 bool MetaspaceShared::try_link_class(InstanceKlass* ik, TRAPS) {
1829 assert(DumpSharedSpaces, "should only be called during dumping");
1830 if (ik->init_state() < InstanceKlass::linked) {
1831 bool saved = BytecodeVerificationLocal;
1832 if (ik->loader_type() == 0 && ik->class_loader() == NULL) {
1833 // The verification decision is based on BytecodeVerificationRemote
1834 // for non-system classes. Since we are using the NULL classloader
1835 // to load non-system classes for customized class loaders during dumping,
1836 // we need to temporarily change BytecodeVerificationLocal to be the same as
1837 // BytecodeVerificationRemote. Note this can cause the parent system
1838 // classes also being verified. The extra overhead is acceptable during
1839 // dumping.
1840 BytecodeVerificationLocal = BytecodeVerificationRemote;
1841 }
1842 ik->link_class(THREAD);
1843 if (HAS_PENDING_EXCEPTION) {
1844 ResourceMark rm;
1845 log_warning(cds)("Preload Warning: Verification failed for %s",
1846 ik->external_name());
1847 CLEAR_PENDING_EXCEPTION;
1848 ik->set_in_error_state();
1849 _has_error_classes = true;
1850 }
1851 BytecodeVerificationLocal = saved;
1852 return true;
1853 } else {
1854 return false;
1855 }
1856 }
1857
1858 #if INCLUDE_CDS_JAVA_HEAP
1859 void VM_PopulateDumpSharedSpace::dump_java_heap_objects() {
1860 // The closed and open archive heap space has maximum two regions.
1861 // See FileMapInfo::write_archive_heap_regions() for details.
1862 _closed_archive_heap_regions = new GrowableArray<MemRegion>(2);
1863 _open_archive_heap_regions = new GrowableArray<MemRegion>(2);
1864 HeapShared::archive_java_heap_objects(_closed_archive_heap_regions,
1865 _open_archive_heap_regions);
1866 ArchiveCompactor::OtherROAllocMark mark;
1867 HeapShared::write_subgraph_info_table();
1868 }
1869
1870 void VM_PopulateDumpSharedSpace::dump_archive_heap_oopmaps() {
1871 if (HeapShared::is_heap_object_archiving_allowed()) {
1872 _closed_archive_heap_oopmaps = new GrowableArray<ArchiveHeapOopmapInfo>(2);
1873 dump_archive_heap_oopmaps(_closed_archive_heap_regions, _closed_archive_heap_oopmaps);
1874
1875 _open_archive_heap_oopmaps = new GrowableArray<ArchiveHeapOopmapInfo>(2);
1876 dump_archive_heap_oopmaps(_open_archive_heap_regions, _open_archive_heap_oopmaps);
1877 }
1878 }
1879
1880 void VM_PopulateDumpSharedSpace::dump_archive_heap_oopmaps(GrowableArray<MemRegion>* regions,
1881 GrowableArray<ArchiveHeapOopmapInfo>* oopmaps) {
1882 for (int i=0; i<regions->length(); i++) {
1883 ResourceBitMap oopmap = HeapShared::calculate_oopmap(regions->at(i));
1884 size_t size_in_bits = oopmap.size();
1885 size_t size_in_bytes = oopmap.size_in_bytes();
1886 uintptr_t* buffer = (uintptr_t*)_ro_region.allocate(size_in_bytes, sizeof(intptr_t));
1887 oopmap.write_to(buffer, size_in_bytes);
1888 log_info(cds)("Oopmap = " INTPTR_FORMAT " (" SIZE_FORMAT_W(6) " bytes) for heap region "
1889 INTPTR_FORMAT " (" SIZE_FORMAT_W(8) " bytes)",
1890 p2i(buffer), size_in_bytes,
1891 p2i(regions->at(i).start()), regions->at(i).byte_size());
1892
1893 ArchiveHeapOopmapInfo info;
1894 info._oopmap = (address)buffer;
1895 info._oopmap_size_in_bits = size_in_bits;
1896 oopmaps->append(info);
1897 }
1898 }
1899 #endif // INCLUDE_CDS_JAVA_HEAP
1900
1901 void ReadClosure::do_ptr(void** p) {
1902 assert(*p == NULL, "initializing previous initialized pointer.");
1903 intptr_t obj = nextPtr();
1904 assert((intptr_t)obj >= 0 || (intptr_t)obj < -100,
1905 "hit tag while initializing ptrs.");
1906 *p = (void*)obj;
1907 }
1908
1909 void ReadClosure::do_u4(u4* p) {
1910 intptr_t obj = nextPtr();
1911 *p = (u4)(uintx(obj));
1912 }
1913
1914 void ReadClosure::do_bool(bool* p) {
1915 intptr_t obj = nextPtr();
1916 *p = (bool)(uintx(obj));
1917 }
1918
1919 void ReadClosure::do_tag(int tag) {
1920 int old_tag;
1921 old_tag = (int)(intptr_t)nextPtr();
1922 // do_int(&old_tag);
1923 assert(tag == old_tag, "old tag doesn't match");
1924 FileMapInfo::assert_mark(tag == old_tag);
1925 }
1926
1927 void ReadClosure::do_oop(oop *p) {
1928 narrowOop o = (narrowOop)nextPtr();
1929 if (o == 0 || !HeapShared::open_archive_heap_region_mapped()) {
1930 p = NULL;
1931 } else {
1932 assert(HeapShared::is_heap_object_archiving_allowed(),
1933 "Archived heap object is not allowed");
1934 assert(HeapShared::open_archive_heap_region_mapped(),
1935 "Open archive heap region is not mapped");
1936 *p = HeapShared::decode_from_archive(o);
1937 }
1938 }
1939
1940 void ReadClosure::do_region(u_char* start, size_t size) {
1941 assert((intptr_t)start % sizeof(intptr_t) == 0, "bad alignment");
1942 assert(size % sizeof(intptr_t) == 0, "bad size");
1943 do_tag((int)size);
1944 while (size > 0) {
1945 *(intptr_t*)start = nextPtr();
1946 start += sizeof(intptr_t);
1947 size -= sizeof(intptr_t);
1948 }
1949 }
1950
1951 void MetaspaceShared::set_shared_metaspace_range(void* base, void* top) {
1952 _shared_metaspace_static_top = top;
1953 MetaspaceObj::set_shared_metaspace_range(base, top);
1954 }
1955
1956 // Return true if given address is in the misc data region
1957 bool MetaspaceShared::is_in_shared_region(const void* p, int idx) {
1958 return UseSharedSpaces && FileMapInfo::current_info()->is_in_shared_region(p, idx);
1959 }
1960
1961 bool MetaspaceShared::is_in_trampoline_frame(address addr) {
1962 if (UseSharedSpaces && is_in_shared_region(addr, MetaspaceShared::mc)) {
1963 return true;
1964 }
1965 return false;
1966 }
1967
1968 bool MetaspaceShared::is_shared_dynamic(void* p) {
1969 if ((p < MetaspaceObj::shared_metaspace_top()) &&
1970 (p >= _shared_metaspace_static_top)) {
1971 return true;
1972 } else {
1973 return false;
1974 }
1975 }
1976
1977 // Map shared spaces at requested addresses and return if succeeded.
1978 bool MetaspaceShared::map_shared_spaces(FileMapInfo* mapinfo) {
1979 size_t image_alignment = mapinfo->alignment();
1980
1981 #ifndef _WINDOWS
1982 // Map in the shared memory and then map the regions on top of it.
1983 // On Windows, don't map the memory here because it will cause the
1984 // mappings of the regions to fail.
1985 ReservedSpace shared_rs = mapinfo->reserve_shared_memory();
1986 if (!shared_rs.is_reserved()) return false;
1987 #endif
1988
1989 assert(!DumpSharedSpaces, "Should not be called with DumpSharedSpaces");
1990
1991 // Map each shared region
1992 int regions[] = {mc, rw, ro, md};
1993 size_t len = sizeof(regions)/sizeof(int);
1994 char* saved_base[] = {NULL, NULL, NULL, NULL};
1995 char* top = mapinfo->map_regions(regions, saved_base, len );
1996
1997 if (top != NULL &&
1998 (image_alignment == (size_t)os::vm_allocation_granularity()) &&
1999 mapinfo->validate_shared_path_table()) {
2000 // Success -- set up MetaspaceObj::_shared_metaspace_{base,top} for
2001 // fast checking in MetaspaceShared::is_in_shared_metaspace() and
2002 // MetaspaceObj::is_shared().
2003 _core_spaces_size = mapinfo->core_spaces_size();
2004 set_shared_metaspace_range((void*)saved_base[0], (void*)top);
2005 return true;
2006 } else {
2007 mapinfo->unmap_regions(regions, saved_base, len);
2008 #ifndef _WINDOWS
2009 // Release the entire mapped region
2010 shared_rs.release();
2011 #endif
2012 // If -Xshare:on is specified, print out the error message and exit VM,
2013 // otherwise, set UseSharedSpaces to false and continue.
2014 if (RequireSharedSpaces || PrintSharedArchiveAndExit) {
2015 vm_exit_during_initialization("Unable to use shared archive.", "Failed map_region for using -Xshare:on.");
2016 } else {
2017 FLAG_SET_DEFAULT(UseSharedSpaces, false);
2018 }
2019 return false;
2020 }
2021 }
2022
2023 // Read the miscellaneous data from the shared file, and
2024 // serialize it out to its various destinations.
2025
2026 void MetaspaceShared::initialize_shared_spaces() {
2027 FileMapInfo *mapinfo = FileMapInfo::current_info();
2028 _i2i_entry_code_buffers = mapinfo->i2i_entry_code_buffers();
2029 _i2i_entry_code_buffers_size = mapinfo->i2i_entry_code_buffers_size();
2030 // _core_spaces_size is loaded from the shared archive immediatelly after mapping
2031 assert(_core_spaces_size == mapinfo->core_spaces_size(), "sanity");
2032 char* buffer = mapinfo->misc_data_patching_start();
2033 clone_cpp_vtables((intptr_t*)buffer);
2034
2035 // Verify various attributes of the archive, plus initialize the
2036 // shared string/symbol tables
2037 buffer = mapinfo->serialized_data_start();
2038 intptr_t* array = (intptr_t*)buffer;
2039 ReadClosure rc(&array);
2040 serialize(&rc);
2041
2042 // Initialize the run-time symbol table.
2043 SymbolTable::create_table();
2044
2045 mapinfo->patch_archived_heap_embedded_pointers();
2046
2047 // Close the mapinfo file
2048 mapinfo->close();
2049
2050 if (PrintSharedArchiveAndExit) {
2051 if (PrintSharedDictionary) {
2052 tty->print_cr("\nShared classes:\n");
2053 SystemDictionaryShared::print_on(tty);
2054 }
2055 if (_archive_loading_failed) {
2056 tty->print_cr("archive is invalid");
2057 vm_exit(1);
2058 } else {
2059 tty->print_cr("archive is valid");
2060 vm_exit(0);
2061 }
2062 }
2063 }
2064
2065 // JVM/TI RedefineClasses() support:
2066 bool MetaspaceShared::remap_shared_readonly_as_readwrite() {
2067 assert(SafepointSynchronize::is_at_safepoint(), "must be at safepoint");
2068
2069 if (UseSharedSpaces) {
2070 // remap the shared readonly space to shared readwrite, private
2071 FileMapInfo* mapinfo = FileMapInfo::current_info();
2072 if (!mapinfo->remap_shared_readonly_as_readwrite()) {
2073 return false;
2074 }
2075 if (FileMapInfo::dynamic_info() != NULL) {
2076 mapinfo = FileMapInfo::dynamic_info();
2077 if (!mapinfo->remap_shared_readonly_as_readwrite()) {
2078 return false;
2079 }
2080 }
2081 _remapped_readwrite = true;
2082 }
2083 return true;
2084 }
2085
2086 void MetaspaceShared::report_out_of_space(const char* name, size_t needed_bytes) {
2087 // This is highly unlikely to happen on 64-bits because we have reserved a 4GB space.
2088 // On 32-bit we reserve only 256MB so you could run out of space with 100,000 classes
2089 // or so.
2090 _mc_region.print_out_of_space_msg(name, needed_bytes);
2091 _rw_region.print_out_of_space_msg(name, needed_bytes);
2092 _ro_region.print_out_of_space_msg(name, needed_bytes);
2093 _md_region.print_out_of_space_msg(name, needed_bytes);
2094
2095 vm_exit_during_initialization(err_msg("Unable to allocate from '%s' region", name),
2096 "Please reduce the number of shared classes.");
2097 }