1 /*
2 * Copyright (c) 2012, 2018, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 #include "precompiled.hpp"
26 #include "jvm.h"
27 #include "classfile/classLoaderDataGraph.hpp"
28 #include "classfile/classListParser.hpp"
29 #include "classfile/classLoaderExt.hpp"
30 #include "classfile/dictionary.hpp"
31 #include "classfile/loaderConstraints.hpp"
32 #include "classfile/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 "interpreter/bytecodeStream.hpp"
40 #include "interpreter/bytecodes.hpp"
41 #include "logging/log.hpp"
42 #include "logging/logMessage.hpp"
43 #include "memory/filemap.hpp"
44 #include "memory/heapShared.inline.hpp"
45 #include "memory/metaspace.hpp"
46 #include "memory/metaspaceClosure.hpp"
47 #include "memory/metaspaceShared.hpp"
48 #include "memory/resourceArea.hpp"
49 #include "oops/compressedOops.inline.hpp"
50 #include "oops/instanceClassLoaderKlass.hpp"
51 #include "oops/instanceMirrorKlass.hpp"
52 #include "oops/instanceRefKlass.hpp"
53 #include "oops/objArrayKlass.hpp"
54 #include "oops/objArrayOop.hpp"
55 #include "oops/oop.inline.hpp"
56 #include "oops/typeArrayKlass.hpp"
57 #include "prims/jvmtiRedefineClasses.hpp"
58 #include "runtime/handles.inline.hpp"
59 #include "runtime/os.hpp"
60 #include "runtime/safepointVerifiers.hpp"
61 #include "runtime/signature.hpp"
62 #include "runtime/timerTrace.hpp"
63 #include "runtime/vmThread.hpp"
64 #include "runtime/vmOperations.hpp"
65 #include "utilities/align.hpp"
66 #include "utilities/bitMap.hpp"
67 #include "utilities/defaultStream.hpp"
68 #include "utilities/hashtable.inline.hpp"
69 #if INCLUDE_G1GC
70 #include "gc/g1/g1CollectedHeap.hpp"
71 #endif
72
73 ReservedSpace MetaspaceShared::_shared_rs;
74 VirtualSpace MetaspaceShared::_shared_vs;
75 MetaspaceSharedStats MetaspaceShared::_stats;
76 bool MetaspaceShared::_has_error_classes;
77 bool MetaspaceShared::_archive_loading_failed = false;
78 bool MetaspaceShared::_remapped_readwrite = false;
79 address MetaspaceShared::_cds_i2i_entry_code_buffers = NULL;
80 size_t MetaspaceShared::_cds_i2i_entry_code_buffers_size = 0;
81 size_t MetaspaceShared::_core_spaces_size = 0;
82
83 // The CDS archive is divided into the following regions:
84 // mc - misc code (the method entry trampolines)
85 // rw - read-write metadata
86 // ro - read-only metadata and read-only tables
87 // md - misc data (the c++ vtables)
88 // od - optional data (original class files)
89 //
90 // ca0 - closed archive heap space #0
91 // ca1 - closed archive heap space #1 (may be empty)
92 // oa0 - open archive heap space #0
93 // oa1 - open archive heap space #1 (may be empty)
94 //
95 // The mc, rw, ro, md and od regions are linearly allocated, starting from
96 // SharedBaseAddress, in the order of mc->rw->ro->md->od. The size of these 5 regions
97 // are page-aligned, and there's no gap between any consecutive regions.
98 //
99 // These 5 regions are populated in the following steps:
100 // [1] All classes are loaded in MetaspaceShared::preload_classes(). All metadata are
101 // temporarily allocated outside of the shared regions. Only the method entry
102 // trampolines are written into the mc region.
103 // [2] ArchiveCompactor copies RW metadata into the rw region.
104 // [3] ArchiveCompactor copies RO metadata into the ro region.
105 // [4] SymbolTable, StringTable, SystemDictionary, and a few other read-only data
106 // are copied into the ro region as read-only tables.
107 // [5] C++ vtables are copied into the md region.
108 // [6] Original class files are copied into the od region.
109 //
110 // The s0/s1 and oa0/oa1 regions are populated inside HeapShared::archive_java_heap_objects.
111 // Their layout is independent of the other 5 regions.
112
113 class DumpRegion {
114 private:
115 const char* _name;
116 char* _base;
117 char* _top;
118 char* _end;
119 bool _is_packed;
120
121 char* expand_top_to(char* newtop) {
122 assert(is_allocatable(), "must be initialized and not packed");
123 assert(newtop >= _top, "must not grow backwards");
124 if (newtop > _end) {
125 MetaspaceShared::report_out_of_space(_name, newtop - _top);
126 ShouldNotReachHere();
127 }
128 uintx delta = MetaspaceShared::object_delta_uintx(newtop);
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 public:
143 DumpRegion(const char* name) : _name(name), _base(NULL), _top(NULL), _end(NULL), _is_packed(false) {}
144
145 char* allocate(size_t num_bytes, size_t alignment=BytesPerWord) {
146 char* p = (char*)align_up(_top, alignment);
147 char* newtop = p + align_up(num_bytes, alignment);
148 expand_top_to(newtop);
149 memset(p, 0, newtop - p);
150 return p;
151 }
152
153 void append_intptr_t(intptr_t n) {
154 assert(is_aligned(_top, sizeof(intptr_t)), "bad alignment");
155 intptr_t *p = (intptr_t*)_top;
156 char* newtop = _top + sizeof(intptr_t);
157 expand_top_to(newtop);
158 *p = n;
159 }
160
161 char* base() const { return _base; }
162 char* top() const { return _top; }
163 char* end() const { return _end; }
164 size_t reserved() const { return _end - _base; }
165 size_t used() const { return _top - _base; }
166 bool is_packed() const { return _is_packed; }
167 bool is_allocatable() const {
168 return !is_packed() && _base != NULL;
169 }
170
171 void print(size_t total_bytes) const {
172 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,
173 _name, used(), percent_of(used(), total_bytes), reserved(), percent_of(used(), reserved()), p2i(_base));
174 }
175 void print_out_of_space_msg(const char* failing_region, size_t needed_bytes) {
176 tty->print("[%-8s] " PTR_FORMAT " - " PTR_FORMAT " capacity =%9d, allocated =%9d",
177 _name, p2i(_base), p2i(_top), int(_end - _base), int(_top - _base));
178 if (strcmp(_name, failing_region) == 0) {
179 tty->print_cr(" required = %d", int(needed_bytes));
180 } else {
181 tty->cr();
182 }
183 }
184
185 void init(const ReservedSpace* rs) {
186 _base = _top = rs->base();
187 _end = rs->end();
188 }
189 void init(char* b, char* t, char* e) {
190 _base = b;
191 _top = t;
192 _end = e;
193 }
194
195 void pack(DumpRegion* next = NULL) {
196 assert(!is_packed(), "sanity");
197 _end = (char*)align_up(_top, Metaspace::reserve_alignment());
198 _is_packed = true;
199 if (next != NULL) {
200 next->_base = next->_top = this->_end;
201 next->_end = MetaspaceShared::shared_rs()->end();
202 }
203 }
204 bool contains(char* p) {
205 return base() <= p && p < top();
206 }
207 };
208
209
210 DumpRegion _mc_region("mc"), _ro_region("ro"), _rw_region("rw"), _md_region("md"), _od_region("od");
211 size_t _total_closed_archive_region_size = 0, _total_open_archive_region_size = 0;
212
213 char* MetaspaceShared::misc_code_space_alloc(size_t num_bytes) {
214 return _mc_region.allocate(num_bytes);
215 }
216
217 char* MetaspaceShared::read_only_space_alloc(size_t num_bytes) {
218 return _ro_region.allocate(num_bytes);
219 }
220
221 char* MetaspaceShared::read_only_space_top() {
222 return _ro_region.top();
223 }
224
225 void MetaspaceShared::initialize_runtime_shared_and_meta_spaces() {
226 assert(UseSharedSpaces, "Must be called when UseSharedSpaces is enabled");
227
228 // If using shared space, open the file that contains the shared space
229 // and map in the memory before initializing the rest of metaspace (so
230 // the addresses don't conflict)
231 address cds_address = NULL;
232 FileMapInfo* mapinfo = new FileMapInfo();
233
234 // Open the shared archive file, read and validate the header. If
235 // initialization fails, shared spaces [UseSharedSpaces] are
236 // disabled and the file is closed.
237 // Map in spaces now also
238 if (mapinfo->initialize() && map_shared_spaces(mapinfo)) {
239 size_t cds_total = core_spaces_size();
240 cds_address = (address)mapinfo->region_addr(0);
241 #ifdef _LP64
242 if (Metaspace::using_class_space()) {
243 char* cds_end = (char*)(cds_address + cds_total);
244 cds_end = (char *)align_up(cds_end, Metaspace::reserve_alignment());
245 // If UseCompressedClassPointers is set then allocate the metaspace area
246 // above the heap and above the CDS area (if it exists).
247 Metaspace::allocate_metaspace_compressed_klass_ptrs(cds_end, cds_address);
248 // map_heap_regions() compares the current narrow oop and klass encodings
249 // with the archived ones, so it must be done after all encodings are determined.
250 mapinfo->map_heap_regions();
251 }
252 Universe::set_narrow_klass_range(CompressedClassSpaceSize);
253 #endif // _LP64
254 } else {
255 assert(!mapinfo->is_open() && !UseSharedSpaces,
256 "archive file not closed or shared spaces not disabled.");
257 }
258 }
259
260 void MetaspaceShared::initialize_dumptime_shared_and_meta_spaces() {
261 assert(DumpSharedSpaces, "should be called for dump time only");
262 const size_t reserve_alignment = Metaspace::reserve_alignment();
263 bool large_pages = false; // No large pages when dumping the CDS archive.
264 char* shared_base = (char*)align_up((char*)SharedBaseAddress, reserve_alignment);
265
266 #ifdef _LP64
267 // On 64-bit VM, the heap and class space layout will be the same as if
268 // you're running in -Xshare:on mode:
269 //
270 // +-- SharedBaseAddress (default = 0x800000000)
271 // v
272 // +-..---------+---------+ ... +----+----+----+----+----+---------------+
273 // | Heap | Archive | | MC | RW | RO | MD | OD | class space |
274 // +-..---------+---------+ ... +----+----+----+----+----+---------------+
275 // |<-- MaxHeapSize -->| |<-- UnscaledClassSpaceMax = 4GB ------->|
276 //
277 const uint64_t UnscaledClassSpaceMax = (uint64_t(max_juint) + 1);
278 const size_t cds_total = align_down(UnscaledClassSpaceMax, reserve_alignment);
279 #else
280 // We don't support archives larger than 256MB on 32-bit due to limited virtual address space.
281 size_t cds_total = align_down(256*M, reserve_alignment);
282 #endif
283
284 // First try to reserve the space at the specified SharedBaseAddress.
285 _shared_rs = ReservedSpace(cds_total, reserve_alignment, large_pages, shared_base);
286 if (_shared_rs.is_reserved()) {
287 assert(shared_base == 0 || _shared_rs.base() == shared_base, "should match");
288 } else {
289 // Get a mmap region anywhere if the SharedBaseAddress fails.
290 _shared_rs = ReservedSpace(cds_total, reserve_alignment, large_pages);
291 }
292 if (!_shared_rs.is_reserved()) {
293 vm_exit_during_initialization("Unable to reserve memory for shared space",
294 err_msg(SIZE_FORMAT " bytes.", cds_total));
295 }
296
297 #ifdef _LP64
298 // During dump time, we allocate 4GB (UnscaledClassSpaceMax) of space and split it up:
299 // + The upper 1 GB is used as the "temporary compressed class space" -- preload_classes()
300 // will store Klasses into this space.
301 // + The lower 3 GB is used for the archive -- when preload_classes() is done,
302 // ArchiveCompactor will copy the class metadata into this space, first the RW parts,
303 // then the RO parts.
304
305 assert(UseCompressedOops && UseCompressedClassPointers,
306 "UseCompressedOops and UseCompressedClassPointers must be set");
307
308 size_t max_archive_size = align_down(cds_total * 3 / 4, reserve_alignment);
309 ReservedSpace tmp_class_space = _shared_rs.last_part(max_archive_size);
310 CompressedClassSpaceSize = align_down(tmp_class_space.size(), reserve_alignment);
311 _shared_rs = _shared_rs.first_part(max_archive_size);
312
313 // Set up compress class pointers.
314 Universe::set_narrow_klass_base((address)_shared_rs.base());
315 // Set narrow_klass_shift to be LogKlassAlignmentInBytes. This is consistent
316 // with AOT.
317 Universe::set_narrow_klass_shift(LogKlassAlignmentInBytes);
318 // Set the range of klass addresses to 4GB.
319 Universe::set_narrow_klass_range(cds_total);
320
321 Metaspace::initialize_class_space(tmp_class_space);
322 log_info(cds)("narrow_klass_base = " PTR_FORMAT ", narrow_klass_shift = %d",
323 p2i(Universe::narrow_klass_base()), Universe::narrow_klass_shift());
324
325 log_info(cds)("Allocated temporary class space: " SIZE_FORMAT " bytes at " PTR_FORMAT,
326 CompressedClassSpaceSize, p2i(tmp_class_space.base()));
327 #endif
328
329 // Start with 0 committed bytes. The memory will be committed as needed by
330 // MetaspaceShared::commit_shared_space_to().
331 if (!_shared_vs.initialize(_shared_rs, 0)) {
332 vm_exit_during_initialization("Unable to allocate memory for shared space");
333 }
334
335 _mc_region.init(&_shared_rs);
336 SharedBaseAddress = (size_t)_shared_rs.base();
337 tty->print_cr("Allocated shared space: " SIZE_FORMAT " bytes at " PTR_FORMAT,
338 _shared_rs.size(), p2i(_shared_rs.base()));
339 }
340
341 // Called by universe_post_init()
342 void MetaspaceShared::post_initialize(TRAPS) {
343 if (UseSharedSpaces) {
344 int size = FileMapInfo::get_number_of_shared_paths();
345 if (size > 0) {
346 SystemDictionaryShared::allocate_shared_data_arrays(size, THREAD);
347 FileMapHeader* header = FileMapInfo::current_info()->header();
348 ClassLoaderExt::init_paths_start_index(header->_app_class_paths_start_index);
349 ClassLoaderExt::init_app_module_paths_start_index(header->_app_module_paths_start_index);
350 }
351 }
352 }
353
354 static GrowableArray<Handle>* _extra_interned_strings = NULL;
355
356 void MetaspaceShared::read_extra_data(const char* filename, TRAPS) {
357 _extra_interned_strings = new (ResourceObj::C_HEAP, mtInternal)GrowableArray<Handle>(10000, true);
358
359 HashtableTextDump reader(filename);
360 reader.check_version("VERSION: 1.0");
361
362 while (reader.remain() > 0) {
363 int utf8_length;
364 int prefix_type = reader.scan_prefix(&utf8_length);
365 ResourceMark rm(THREAD);
366 if (utf8_length == 0x7fffffff) {
367 // buf_len will overflown 32-bit value.
368 vm_exit_during_initialization(err_msg("string length too large: %d", utf8_length));
369 }
370 int buf_len = utf8_length+1;
371 char* utf8_buffer = NEW_RESOURCE_ARRAY(char, buf_len);
372 reader.get_utf8(utf8_buffer, utf8_length);
373 utf8_buffer[utf8_length] = '\0';
374
375 if (prefix_type == HashtableTextDump::SymbolPrefix) {
376 SymbolTable::new_permanent_symbol(utf8_buffer, THREAD);
377 } else{
378 assert(prefix_type == HashtableTextDump::StringPrefix, "Sanity");
379 oop s = StringTable::intern(utf8_buffer, THREAD);
380
381 if (HAS_PENDING_EXCEPTION) {
382 log_warning(cds, heap)("[line %d] extra interned string allocation failed; size too large: %d",
383 reader.last_line_no(), utf8_length);
384 CLEAR_PENDING_EXCEPTION;
385 } else {
386 #if INCLUDE_G1GC
387 if (UseG1GC) {
388 typeArrayOop body = java_lang_String::value(s);
389 const HeapRegion* hr = G1CollectedHeap::heap()->heap_region_containing(body);
390 if (hr->is_humongous()) {
391 // Don't keep it alive, so it will be GC'ed before we dump the strings, in order
392 // to maximize free heap space and minimize fragmentation.
393 log_warning(cds, heap)("[line %d] extra interned string ignored; size too large: %d",
394 reader.last_line_no(), utf8_length);
395 continue;
396 }
397 }
398 #endif
399 // Interned strings are GC'ed if there are no references to it, so let's
400 // add a reference to keep this string alive.
401 assert(s != NULL, "must succeed");
402 Handle h(THREAD, s);
403 _extra_interned_strings->append(h);
404 }
405 }
406 }
407 }
408
409 void MetaspaceShared::commit_shared_space_to(char* newtop) {
410 assert(DumpSharedSpaces, "dump-time only");
411 char* base = _shared_rs.base();
412 size_t need_committed_size = newtop - base;
413 size_t has_committed_size = _shared_vs.committed_size();
414 if (need_committed_size < has_committed_size) {
415 return;
416 }
417
418 size_t min_bytes = need_committed_size - has_committed_size;
419 size_t preferred_bytes = 1 * M;
420 size_t uncommitted = _shared_vs.reserved_size() - has_committed_size;
421
422 size_t commit = MAX2(min_bytes, preferred_bytes);
423 assert(commit <= uncommitted, "sanity");
424
425 bool result = _shared_vs.expand_by(commit, false);
426 if (!result) {
427 vm_exit_during_initialization(err_msg("Failed to expand shared space to " SIZE_FORMAT " bytes",
428 need_committed_size));
429 }
430
431 log_info(cds)("Expanding shared spaces by " SIZE_FORMAT_W(7) " bytes [total " SIZE_FORMAT_W(9) " bytes ending at %p]",
432 commit, _shared_vs.actual_committed_size(), _shared_vs.high());
433 }
434
435 // Read/write a data stream for restoring/preserving metadata pointers and
436 // miscellaneous data from/to the shared archive file.
437
438 void MetaspaceShared::serialize(SerializeClosure* soc) {
439 int tag = 0;
440 soc->do_tag(--tag);
441
442 // Verify the sizes of various metadata in the system.
443 soc->do_tag(sizeof(Method));
444 soc->do_tag(sizeof(ConstMethod));
445 soc->do_tag(arrayOopDesc::base_offset_in_bytes(T_BYTE));
446 soc->do_tag(sizeof(ConstantPool));
447 soc->do_tag(sizeof(ConstantPoolCache));
448 soc->do_tag(objArrayOopDesc::base_offset_in_bytes());
449 soc->do_tag(typeArrayOopDesc::base_offset_in_bytes(T_BYTE));
450 soc->do_tag(sizeof(Symbol));
451
452 // Dump/restore miscellaneous metadata.
453 Universe::serialize(soc);
454 soc->do_tag(--tag);
455
456 // Dump/restore references to commonly used names and signatures.
457 vmSymbols::serialize(soc);
458 soc->do_tag(--tag);
459
460 // Dump/restore the symbol/string/subgraph_info tables
461 SymbolTable::serialize_shared_table_header(soc);
462 StringTable::serialize_shared_table_header(soc);
463 HeapShared::serialize_subgraph_info_table_header(soc);
464 SystemDictionaryShared::serialize_dictionary_headers(soc);
465
466 JavaClasses::serialize_offsets(soc);
467 InstanceMirrorKlass::serialize_offsets(soc);
468 soc->do_tag(--tag);
469
470 soc->do_tag(666);
471 }
472
473 address MetaspaceShared::cds_i2i_entry_code_buffers(size_t total_size) {
474 if (DumpSharedSpaces) {
475 if (_cds_i2i_entry_code_buffers == NULL) {
476 _cds_i2i_entry_code_buffers = (address)misc_code_space_alloc(total_size);
477 _cds_i2i_entry_code_buffers_size = total_size;
478 }
479 } else if (UseSharedSpaces) {
480 assert(_cds_i2i_entry_code_buffers != NULL, "must already been initialized");
481 } else {
482 return NULL;
483 }
484
485 assert(_cds_i2i_entry_code_buffers_size == total_size, "must not change");
486 return _cds_i2i_entry_code_buffers;
487 }
488
489 // Global object for holding classes that have been loaded. Since this
490 // is run at a safepoint just before exit, this is the entire set of classes.
491 static GrowableArray<Klass*>* _global_klass_objects;
492
493 GrowableArray<Klass*>* MetaspaceShared::collected_klasses() {
494 return _global_klass_objects;
495 }
496
497 static void collect_array_classes(Klass* k) {
498 _global_klass_objects->append_if_missing(k);
499 if (k->is_array_klass()) {
500 // Add in the array classes too
501 ArrayKlass* ak = ArrayKlass::cast(k);
502 Klass* h = ak->higher_dimension();
503 if (h != NULL) {
504 h->array_klasses_do(collect_array_classes);
505 }
506 }
507 }
508
509 class CollectClassesClosure : public KlassClosure {
510 void do_klass(Klass* k) {
511 if (k->is_instance_klass() &&
512 SystemDictionaryShared::is_excluded_class(InstanceKlass::cast(k))) {
513 // Don't add to the _global_klass_objects
514 } else {
515 _global_klass_objects->append_if_missing(k);
516 }
517 if (k->is_array_klass()) {
518 // Add in the array classes too
519 ArrayKlass* ak = ArrayKlass::cast(k);
520 Klass* h = ak->higher_dimension();
521 if (h != NULL) {
522 h->array_klasses_do(collect_array_classes);
523 }
524 }
525 }
526 };
527
528 static void remove_unshareable_in_classes() {
529 for (int i = 0; i < _global_klass_objects->length(); i++) {
530 Klass* k = _global_klass_objects->at(i);
531 if (!k->is_objArray_klass()) {
532 // InstanceKlass and TypeArrayKlass will in turn call remove_unshareable_info
533 // on their array classes.
534 assert(k->is_instance_klass() || k->is_typeArray_klass(), "must be");
535 k->remove_unshareable_info();
536 }
537 }
538 }
539
540 static void remove_java_mirror_in_classes() {
541 for (int i = 0; i < _global_klass_objects->length(); i++) {
542 Klass* k = _global_klass_objects->at(i);
543 if (!k->is_objArray_klass()) {
544 // InstanceKlass and TypeArrayKlass will in turn call remove_unshareable_info
545 // on their array classes.
546 assert(k->is_instance_klass() || k->is_typeArray_klass(), "must be");
547 k->remove_java_mirror();
548 }
549 }
550 }
551
552 static void clear_basic_type_mirrors() {
553 assert(!HeapShared::is_heap_object_archiving_allowed(), "Sanity");
554 Universe::set_int_mirror(NULL);
555 Universe::set_float_mirror(NULL);
556 Universe::set_double_mirror(NULL);
557 Universe::set_byte_mirror(NULL);
558 Universe::set_bool_mirror(NULL);
559 Universe::set_char_mirror(NULL);
560 Universe::set_long_mirror(NULL);
561 Universe::set_short_mirror(NULL);
562 Universe::set_void_mirror(NULL);
563 }
564
565 static void rewrite_nofast_bytecode(Method* method) {
566 BytecodeStream bcs(method);
567 while (!bcs.is_last_bytecode()) {
568 Bytecodes::Code opcode = bcs.next();
569 switch (opcode) {
570 case Bytecodes::_getfield: *bcs.bcp() = Bytecodes::_nofast_getfield; break;
571 case Bytecodes::_putfield: *bcs.bcp() = Bytecodes::_nofast_putfield; break;
572 case Bytecodes::_aload_0: *bcs.bcp() = Bytecodes::_nofast_aload_0; break;
573 case Bytecodes::_iload: {
574 if (!bcs.is_wide()) {
575 *bcs.bcp() = Bytecodes::_nofast_iload;
576 }
577 break;
578 }
579 default: break;
580 }
581 }
582 }
583
584 // Walk all methods in the class list to ensure that they won't be modified at
585 // run time. This includes:
586 // [1] Rewrite all bytecodes as needed, so that the ConstMethod* will not be modified
587 // at run time by RewriteBytecodes/RewriteFrequentPairs
588 // [2] Assign a fingerprint, so one doesn't need to be assigned at run-time.
589 static void rewrite_nofast_bytecodes_and_calculate_fingerprints() {
590 for (int i = 0; i < _global_klass_objects->length(); i++) {
591 Klass* k = _global_klass_objects->at(i);
592 if (k->is_instance_klass()) {
593 InstanceKlass* ik = InstanceKlass::cast(k);
594 for (int i = 0; i < ik->methods()->length(); i++) {
595 Method* m = ik->methods()->at(i);
596 rewrite_nofast_bytecode(m);
597 Fingerprinter fp(m);
598 // The side effect of this call sets method's fingerprint field.
599 fp.fingerprint();
600 }
601 }
602 }
603 }
604
605 static void relocate_cached_class_file() {
606 for (int i = 0; i < _global_klass_objects->length(); i++) {
607 Klass* k = _global_klass_objects->at(i);
608 if (k->is_instance_klass()) {
609 InstanceKlass* ik = InstanceKlass::cast(k);
610 JvmtiCachedClassFileData* p = ik->get_archived_class_data();
611 if (p != NULL) {
612 int size = offset_of(JvmtiCachedClassFileData, data) + p->length;
613 JvmtiCachedClassFileData* q = (JvmtiCachedClassFileData*)_od_region.allocate(size);
614 q->length = p->length;
615 memcpy(q->data, p->data, p->length);
616 ik->set_archived_class_data(q);
617 }
618 }
619 }
620 }
621
622 // Objects of the Metadata types (such as Klass and ConstantPool) have C++ vtables.
623 // (In GCC this is the field <Type>::_vptr, i.e., first word in the object.)
624 //
625 // Addresses of the vtables and the methods may be different across JVM runs,
626 // if libjvm.so is dynamically loaded at a different base address.
627 //
628 // To ensure that the Metadata objects in the CDS archive always have the correct vtable:
629 //
630 // + at dump time: we redirect the _vptr to point to our own vtables inside
631 // the CDS image
632 // + at run time: we clone the actual contents of the vtables from libjvm.so
633 // into our own tables.
634
635 // Currently, the archive contain ONLY the following types of objects that have C++ vtables.
636 #define CPP_VTABLE_PATCH_TYPES_DO(f) \
637 f(ConstantPool) \
638 f(InstanceKlass) \
639 f(InstanceClassLoaderKlass) \
640 f(InstanceMirrorKlass) \
641 f(InstanceRefKlass) \
642 f(Method) \
643 f(ObjArrayKlass) \
644 f(TypeArrayKlass)
645
646 class CppVtableInfo {
647 intptr_t _vtable_size;
648 intptr_t _cloned_vtable[1];
649 public:
650 static int num_slots(int vtable_size) {
651 return 1 + vtable_size; // Need to add the space occupied by _vtable_size;
652 }
653 int vtable_size() { return int(uintx(_vtable_size)); }
654 void set_vtable_size(int n) { _vtable_size = intptr_t(n); }
655 intptr_t* cloned_vtable() { return &_cloned_vtable[0]; }
656 void zero() { memset(_cloned_vtable, 0, sizeof(intptr_t) * vtable_size()); }
657 // Returns the address of the next CppVtableInfo that can be placed immediately after this CppVtableInfo
658 static size_t byte_size(int vtable_size) {
659 CppVtableInfo i;
660 return pointer_delta(&i._cloned_vtable[vtable_size], &i, sizeof(u1));
661 }
662 };
663
664 template <class T> class CppVtableCloner : public T {
665 static intptr_t* vtable_of(Metadata& m) {
666 return *((intptr_t**)&m);
667 }
668 static CppVtableInfo* _info;
669
670 static int get_vtable_length(const char* name);
671
672 public:
673 // Allocate and initialize the C++ vtable, starting from top, but do not go past end.
674 static intptr_t* allocate(const char* name);
675
676 // Clone the vtable to ...
677 static intptr_t* clone_vtable(const char* name, CppVtableInfo* info);
678
679 static void zero_vtable_clone() {
680 assert(DumpSharedSpaces, "dump-time only");
681 _info->zero();
682 }
683
684 // Switch the vtable pointer to point to the cloned vtable.
685 static void patch(Metadata* obj) {
686 assert(DumpSharedSpaces, "dump-time only");
687 *(void**)obj = (void*)(_info->cloned_vtable());
688 }
689
690 static bool is_valid_shared_object(const T* obj) {
691 intptr_t* vptr = *(intptr_t**)obj;
692 return vptr == _info->cloned_vtable();
693 }
694 };
695
696 template <class T> CppVtableInfo* CppVtableCloner<T>::_info = NULL;
697
698 template <class T>
699 intptr_t* CppVtableCloner<T>::allocate(const char* name) {
700 assert(is_aligned(_md_region.top(), sizeof(intptr_t)), "bad alignment");
701 int n = get_vtable_length(name);
702 _info = (CppVtableInfo*)_md_region.allocate(CppVtableInfo::byte_size(n), sizeof(intptr_t));
703 _info->set_vtable_size(n);
704
705 intptr_t* p = clone_vtable(name, _info);
706 assert((char*)p == _md_region.top(), "must be");
707
708 return p;
709 }
710
711 template <class T>
712 intptr_t* CppVtableCloner<T>::clone_vtable(const char* name, CppVtableInfo* info) {
713 if (!DumpSharedSpaces) {
714 assert(_info == 0, "_info is initialized only at dump time");
715 _info = info; // Remember it -- it will be used by MetaspaceShared::is_valid_shared_method()
716 }
717 T tmp; // Allocate temporary dummy metadata object to get to the original vtable.
718 int n = info->vtable_size();
719 intptr_t* srcvtable = vtable_of(tmp);
720 intptr_t* dstvtable = info->cloned_vtable();
721
722 // We already checked (and, if necessary, adjusted n) when the vtables were allocated, so we are
723 // safe to do memcpy.
724 log_debug(cds, vtables)("Copying %3d vtable entries for %s", n, name);
725 memcpy(dstvtable, srcvtable, sizeof(intptr_t) * n);
726 return dstvtable + n;
727 }
728
729 // To determine the size of the vtable for each type, we use the following
730 // trick by declaring 2 subclasses:
731 //
732 // class CppVtableTesterA: public InstanceKlass {virtual int last_virtual_method() {return 1;} };
733 // class CppVtableTesterB: public InstanceKlass {virtual void* last_virtual_method() {return NULL}; };
734 //
735 // CppVtableTesterA and CppVtableTesterB's vtables have the following properties:
736 // - Their size (N+1) is exactly one more than the size of InstanceKlass's vtable (N)
737 // - The first N entries have are exactly the same as in InstanceKlass's vtable.
738 // - Their last entry is different.
739 //
740 // So to determine the value of N, we just walk CppVtableTesterA and CppVtableTesterB's tables
741 // and find the first entry that's different.
742 //
743 // This works on all C++ compilers supported by Oracle, but you may need to tweak it for more
744 // esoteric compilers.
745
746 template <class T> class CppVtableTesterB: public T {
747 public:
748 virtual int last_virtual_method() {return 1;}
749 };
750
751 template <class T> class CppVtableTesterA : public T {
752 public:
753 virtual void* last_virtual_method() {
754 // Make this different than CppVtableTesterB::last_virtual_method so the C++
755 // compiler/linker won't alias the two functions.
756 return NULL;
757 }
758 };
759
760 template <class T>
761 int CppVtableCloner<T>::get_vtable_length(const char* name) {
762 CppVtableTesterA<T> a;
763 CppVtableTesterB<T> b;
764
765 intptr_t* avtable = vtable_of(a);
766 intptr_t* bvtable = vtable_of(b);
767
768 // Start at slot 1, because slot 0 may be RTTI (on Solaris/Sparc)
769 int vtable_len = 1;
770 for (; ; vtable_len++) {
771 if (avtable[vtable_len] != bvtable[vtable_len]) {
772 break;
773 }
774 }
775 log_debug(cds, vtables)("Found %3d vtable entries for %s", vtable_len, name);
776
777 return vtable_len;
778 }
779
780 #define ALLOC_CPP_VTABLE_CLONE(c) \
781 CppVtableCloner<c>::allocate(#c);
782
783 #define CLONE_CPP_VTABLE(c) \
784 p = CppVtableCloner<c>::clone_vtable(#c, (CppVtableInfo*)p);
785
786 #define ZERO_CPP_VTABLE(c) \
787 CppVtableCloner<c>::zero_vtable_clone();
788
789 // This can be called at both dump time and run time.
790 intptr_t* MetaspaceShared::clone_cpp_vtables(intptr_t* p) {
791 assert(DumpSharedSpaces || UseSharedSpaces, "sanity");
792 CPP_VTABLE_PATCH_TYPES_DO(CLONE_CPP_VTABLE);
793 return p;
794 }
795
796 void MetaspaceShared::zero_cpp_vtable_clones_for_writing() {
797 assert(DumpSharedSpaces, "dump-time only");
798 CPP_VTABLE_PATCH_TYPES_DO(ZERO_CPP_VTABLE);
799 }
800
801 // Allocate and initialize the C++ vtables, starting from top, but do not go past end.
802 void MetaspaceShared::allocate_cpp_vtable_clones() {
803 assert(DumpSharedSpaces, "dump-time only");
804 // Layout (each slot is a intptr_t):
805 // [number of slots in the first vtable = n1]
806 // [ <n1> slots for the first vtable]
807 // [number of slots in the first second = n2]
808 // [ <n2> slots for the second vtable]
809 // ...
810 // The order of the vtables is the same as the CPP_VTAB_PATCH_TYPES_DO macro.
811 CPP_VTABLE_PATCH_TYPES_DO(ALLOC_CPP_VTABLE_CLONE);
812 }
813
814 // Switch the vtable pointer to point to the cloned vtable. We assume the
815 // vtable pointer is in first slot in object.
816 void MetaspaceShared::patch_cpp_vtable_pointers() {
817 int n = _global_klass_objects->length();
818 for (int i = 0; i < n; i++) {
819 Klass* obj = _global_klass_objects->at(i);
820 if (obj->is_instance_klass()) {
821 InstanceKlass* ik = InstanceKlass::cast(obj);
822 if (ik->is_class_loader_instance_klass()) {
823 CppVtableCloner<InstanceClassLoaderKlass>::patch(ik);
824 } else if (ik->is_reference_instance_klass()) {
825 CppVtableCloner<InstanceRefKlass>::patch(ik);
826 } else if (ik->is_mirror_instance_klass()) {
827 CppVtableCloner<InstanceMirrorKlass>::patch(ik);
828 } else {
829 CppVtableCloner<InstanceKlass>::patch(ik);
830 }
831 ConstantPool* cp = ik->constants();
832 CppVtableCloner<ConstantPool>::patch(cp);
833 for (int j = 0; j < ik->methods()->length(); j++) {
834 Method* m = ik->methods()->at(j);
835 CppVtableCloner<Method>::patch(m);
836 assert(CppVtableCloner<Method>::is_valid_shared_object(m), "must be");
837 }
838 } else if (obj->is_objArray_klass()) {
839 CppVtableCloner<ObjArrayKlass>::patch(obj);
840 } else {
841 assert(obj->is_typeArray_klass(), "sanity");
842 CppVtableCloner<TypeArrayKlass>::patch(obj);
843 }
844 }
845 }
846
847 bool MetaspaceShared::is_valid_shared_method(const Method* m) {
848 assert(is_in_shared_metaspace(m), "must be");
849 return CppVtableCloner<Method>::is_valid_shared_object(m);
850 }
851
852 // Closure for serializing initialization data out to a data area to be
853 // written to the shared file.
854
855 class WriteClosure : public SerializeClosure {
856 private:
857 DumpRegion* _dump_region;
858
859 public:
860 WriteClosure(DumpRegion* r) {
861 _dump_region = r;
862 }
863
864 void do_ptr(void** p) {
865 _dump_region->append_intptr_t((intptr_t)*p);
866 }
867
868 void do_u4(u4* p) {
869 void* ptr = (void*)(uintx(*p));
870 do_ptr(&ptr);
871 }
872
873 void do_tag(int tag) {
874 _dump_region->append_intptr_t((intptr_t)tag);
875 }
876
877 void do_oop(oop* o) {
878 if (*o == NULL) {
879 _dump_region->append_intptr_t(0);
880 } else {
881 assert(HeapShared::is_heap_object_archiving_allowed(),
882 "Archiving heap object is not allowed");
883 _dump_region->append_intptr_t(
884 (intptr_t)CompressedOops::encode_not_null(*o));
885 }
886 }
887
888 void do_region(u_char* start, size_t size) {
889 assert((intptr_t)start % sizeof(intptr_t) == 0, "bad alignment");
890 assert(size % sizeof(intptr_t) == 0, "bad size");
891 do_tag((int)size);
892 while (size > 0) {
893 _dump_region->append_intptr_t(*(intptr_t*)start);
894 start += sizeof(intptr_t);
895 size -= sizeof(intptr_t);
896 }
897 }
898
899 bool reading() const { return false; }
900 };
901
902 // This is for dumping detailed statistics for the allocations
903 // in the shared spaces.
904 class DumpAllocStats : public ResourceObj {
905 public:
906
907 // Here's poor man's enum inheritance
908 #define SHAREDSPACE_OBJ_TYPES_DO(f) \
909 METASPACE_OBJ_TYPES_DO(f) \
910 f(SymbolHashentry) \
911 f(SymbolBucket) \
912 f(StringHashentry) \
913 f(StringBucket) \
914 f(Other)
915
916 enum Type {
917 // Types are MetaspaceObj::ClassType, MetaspaceObj::SymbolType, etc
918 SHAREDSPACE_OBJ_TYPES_DO(METASPACE_OBJ_TYPE_DECLARE)
919 _number_of_types
920 };
921
922 static const char * type_name(Type type) {
923 switch(type) {
924 SHAREDSPACE_OBJ_TYPES_DO(METASPACE_OBJ_TYPE_NAME_CASE)
925 default:
926 ShouldNotReachHere();
927 return NULL;
928 }
929 }
930
931 public:
932 enum { RO = 0, RW = 1 };
933
934 int _counts[2][_number_of_types];
935 int _bytes [2][_number_of_types];
936
937 DumpAllocStats() {
938 memset(_counts, 0, sizeof(_counts));
939 memset(_bytes, 0, sizeof(_bytes));
940 };
941
942 void record(MetaspaceObj::Type type, int byte_size, bool read_only) {
943 assert(int(type) >= 0 && type < MetaspaceObj::_number_of_types, "sanity");
944 int which = (read_only) ? RO : RW;
945 _counts[which][type] ++;
946 _bytes [which][type] += byte_size;
947 }
948
949 void record_other_type(int byte_size, bool read_only) {
950 int which = (read_only) ? RO : RW;
951 _bytes [which][OtherType] += byte_size;
952 }
953 void print_stats(int ro_all, int rw_all, int mc_all, int md_all);
954 };
955
956 void DumpAllocStats::print_stats(int ro_all, int rw_all, int mc_all, int md_all) {
957 // Calculate size of data that was not allocated by Metaspace::allocate()
958 MetaspaceSharedStats *stats = MetaspaceShared::stats();
959
960 // symbols
961 _counts[RO][SymbolHashentryType] = stats->symbol.hashentry_count;
962 _bytes [RO][SymbolHashentryType] = stats->symbol.hashentry_bytes;
963
964 _counts[RO][SymbolBucketType] = stats->symbol.bucket_count;
965 _bytes [RO][SymbolBucketType] = stats->symbol.bucket_bytes;
966
967 // strings
968 _counts[RO][StringHashentryType] = stats->string.hashentry_count;
969 _bytes [RO][StringHashentryType] = stats->string.hashentry_bytes;
970
971 _counts[RO][StringBucketType] = stats->string.bucket_count;
972 _bytes [RO][StringBucketType] = stats->string.bucket_bytes;
973
974 // TODO: count things like dictionary, vtable, etc
975 _bytes[RW][OtherType] += mc_all + md_all;
976 rw_all += mc_all + md_all; // mc/md are mapped Read/Write
977
978 // prevent divide-by-zero
979 if (ro_all < 1) {
980 ro_all = 1;
981 }
982 if (rw_all < 1) {
983 rw_all = 1;
984 }
985
986 int all_ro_count = 0;
987 int all_ro_bytes = 0;
988 int all_rw_count = 0;
989 int all_rw_bytes = 0;
990
991 // To make fmt_stats be a syntactic constant (for format warnings), use #define.
992 #define fmt_stats "%-20s: %8d %10d %5.1f | %8d %10d %5.1f | %8d %10d %5.1f"
993 const char *sep = "--------------------+---------------------------+---------------------------+--------------------------";
994 const char *hdr = " ro_cnt ro_bytes % | rw_cnt rw_bytes % | all_cnt all_bytes %";
995
996 LogMessage(cds) msg;
997
998 msg.info("Detailed metadata info (excluding od/st regions; rw stats include md/mc regions):");
999 msg.info("%s", hdr);
1000 msg.info("%s", sep);
1001 for (int type = 0; type < int(_number_of_types); type ++) {
1002 const char *name = type_name((Type)type);
1003 int ro_count = _counts[RO][type];
1004 int ro_bytes = _bytes [RO][type];
1005 int rw_count = _counts[RW][type];
1006 int rw_bytes = _bytes [RW][type];
1007 int count = ro_count + rw_count;
1008 int bytes = ro_bytes + rw_bytes;
1009
1010 double ro_perc = percent_of(ro_bytes, ro_all);
1011 double rw_perc = percent_of(rw_bytes, rw_all);
1012 double perc = percent_of(bytes, ro_all + rw_all);
1013
1014 msg.info(fmt_stats, name,
1015 ro_count, ro_bytes, ro_perc,
1016 rw_count, rw_bytes, rw_perc,
1017 count, bytes, perc);
1018
1019 all_ro_count += ro_count;
1020 all_ro_bytes += ro_bytes;
1021 all_rw_count += rw_count;
1022 all_rw_bytes += rw_bytes;
1023 }
1024
1025 int all_count = all_ro_count + all_rw_count;
1026 int all_bytes = all_ro_bytes + all_rw_bytes;
1027
1028 double all_ro_perc = percent_of(all_ro_bytes, ro_all);
1029 double all_rw_perc = percent_of(all_rw_bytes, rw_all);
1030 double all_perc = percent_of(all_bytes, ro_all + rw_all);
1031
1032 msg.info("%s", sep);
1033 msg.info(fmt_stats, "Total",
1034 all_ro_count, all_ro_bytes, all_ro_perc,
1035 all_rw_count, all_rw_bytes, all_rw_perc,
1036 all_count, all_bytes, all_perc);
1037
1038 assert(all_ro_bytes == ro_all, "everything should have been counted");
1039 assert(all_rw_bytes == rw_all, "everything should have been counted");
1040
1041 #undef fmt_stats
1042 }
1043
1044 // Populate the shared space.
1045
1046 class VM_PopulateDumpSharedSpace: public VM_Operation {
1047 private:
1048 GrowableArray<MemRegion> *_closed_archive_heap_regions;
1049 GrowableArray<MemRegion> *_open_archive_heap_regions;
1050
1051 GrowableArray<ArchiveHeapOopmapInfo> *_closed_archive_heap_oopmaps;
1052 GrowableArray<ArchiveHeapOopmapInfo> *_open_archive_heap_oopmaps;
1053
1054 void dump_java_heap_objects() NOT_CDS_JAVA_HEAP_RETURN;
1055 void dump_archive_heap_oopmaps() NOT_CDS_JAVA_HEAP_RETURN;
1056 void dump_archive_heap_oopmaps(GrowableArray<MemRegion>* regions,
1057 GrowableArray<ArchiveHeapOopmapInfo>* oopmaps);
1058 void dump_symbols();
1059 char* dump_read_only_tables();
1060 void print_region_stats();
1061 void print_heap_region_stats(GrowableArray<MemRegion> *heap_mem,
1062 const char *name, const size_t total_size);
1063 public:
1064
1065 VMOp_Type type() const { return VMOp_PopulateDumpSharedSpace; }
1066 void doit(); // outline because gdb sucks
1067 static void write_region(FileMapInfo* mapinfo, int region, DumpRegion* space, bool read_only, bool allow_exec);
1068 bool allow_nested_vm_operations() const { return true; }
1069 }; // class VM_PopulateDumpSharedSpace
1070
1071 class SortedSymbolClosure: public SymbolClosure {
1072 GrowableArray<Symbol*> _symbols;
1073 virtual void do_symbol(Symbol** sym) {
1074 assert((*sym)->is_permanent(), "archived symbols must be permanent");
1075 _symbols.append(*sym);
1076 }
1077 static int compare_symbols_by_address(Symbol** a, Symbol** b) {
1078 if (a[0] < b[0]) {
1079 return -1;
1080 } else if (a[0] == b[0]) {
1081 return 0;
1082 } else {
1083 return 1;
1084 }
1085 }
1086
1087 public:
1088 SortedSymbolClosure() {
1089 SymbolTable::symbols_do(this);
1090 _symbols.sort(compare_symbols_by_address);
1091 }
1092 GrowableArray<Symbol*>* get_sorted_symbols() {
1093 return &_symbols;
1094 }
1095 };
1096
1097 // ArchiveCompactor --
1098 //
1099 // This class is the central piece of shared archive compaction -- all metaspace data are
1100 // initially allocated outside of the shared regions. ArchiveCompactor copies the
1101 // metaspace data into their final location in the shared regions.
1102
1103 class ArchiveCompactor : AllStatic {
1104 static const int INITIAL_TABLE_SIZE = 8087;
1105 static const int MAX_TABLE_SIZE = 1000000;
1106
1107 static DumpAllocStats* _alloc_stats;
1108 static SortedSymbolClosure* _ssc;
1109
1110 typedef KVHashtable<address, address, mtInternal> RelocationTable;
1111 static RelocationTable* _new_loc_table;
1112
1113 public:
1114 static void initialize() {
1115 _alloc_stats = new(ResourceObj::C_HEAP, mtInternal)DumpAllocStats;
1116 _new_loc_table = new RelocationTable(INITIAL_TABLE_SIZE);
1117 }
1118 static DumpAllocStats* alloc_stats() {
1119 return _alloc_stats;
1120 }
1121
1122 // Use this when you allocate space with MetaspaceShare::read_only_space_alloc()
1123 // outside of ArchiveCompactor::allocate(). These are usually for misc tables
1124 // that are allocated in the RO space.
1125 class OtherROAllocMark {
1126 char* _oldtop;
1127 public:
1128 OtherROAllocMark() {
1129 _oldtop = _ro_region.top();
1130 }
1131 ~OtherROAllocMark() {
1132 char* newtop = _ro_region.top();
1133 ArchiveCompactor::alloc_stats()->record_other_type(int(newtop - _oldtop), true);
1134 }
1135 };
1136
1137 static void allocate(MetaspaceClosure::Ref* ref, bool read_only) {
1138 address obj = ref->obj();
1139 int bytes = ref->size() * BytesPerWord;
1140 char* p;
1141 size_t alignment = BytesPerWord;
1142 char* oldtop;
1143 char* newtop;
1144
1145 if (read_only) {
1146 oldtop = _ro_region.top();
1147 p = _ro_region.allocate(bytes, alignment);
1148 newtop = _ro_region.top();
1149 } else {
1150 oldtop = _rw_region.top();
1151 if (ref->msotype() == MetaspaceObj::ClassType) {
1152 // Save a pointer immediate in front of an InstanceKlass, so
1153 // we can do a quick lookup from InstanceKlass* -> RunTimeSharedClassInfo*
1154 // without building another hashtable. See RunTimeSharedClassInfo::get_for()
1155 // in systemDictionaryShared.cpp.
1156 Klass* klass = (Klass*)obj;
1157 if (klass->is_instance_klass()) {
1158 SystemDictionaryShared::validate_before_archiving(InstanceKlass::cast(klass));
1159 _rw_region.allocate(sizeof(address), BytesPerWord);
1160 }
1161 }
1162 p = _rw_region.allocate(bytes, alignment);
1163 newtop = _rw_region.top();
1164 }
1165 memcpy(p, obj, bytes);
1166 assert(_new_loc_table->lookup(obj) == NULL, "each object can be relocated at most once");
1167 _new_loc_table->add(obj, (address)p);
1168 log_trace(cds)("Copy: " PTR_FORMAT " ==> " PTR_FORMAT " %d", p2i(obj), p2i(p), bytes);
1169 if (_new_loc_table->maybe_grow(MAX_TABLE_SIZE)) {
1170 log_info(cds, hashtables)("Expanded _new_loc_table to %d", _new_loc_table->table_size());
1171 }
1172 _alloc_stats->record(ref->msotype(), int(newtop - oldtop), read_only);
1173 }
1174
1175 static address get_new_loc(MetaspaceClosure::Ref* ref) {
1176 address* pp = _new_loc_table->lookup(ref->obj());
1177 assert(pp != NULL, "must be");
1178 return *pp;
1179 }
1180
1181 private:
1182 // Makes a shallow copy of visited MetaspaceObj's
1183 class ShallowCopier: public UniqueMetaspaceClosure {
1184 bool _read_only;
1185 public:
1186 ShallowCopier(bool read_only) : _read_only(read_only) {}
1187
1188 virtual void do_unique_ref(Ref* ref, bool read_only) {
1189 if (read_only == _read_only) {
1190 allocate(ref, read_only);
1191 }
1192 }
1193 };
1194
1195 // Relocate embedded pointers within a MetaspaceObj's shallow copy
1196 class ShallowCopyEmbeddedRefRelocator: public UniqueMetaspaceClosure {
1197 public:
1198 virtual void do_unique_ref(Ref* ref, bool read_only) {
1199 address new_loc = get_new_loc(ref);
1200 RefRelocator refer;
1201 ref->metaspace_pointers_do_at(&refer, new_loc);
1202 }
1203 };
1204
1205 // Relocate a reference to point to its shallow copy
1206 class RefRelocator: public MetaspaceClosure {
1207 public:
1208 virtual bool do_ref(Ref* ref, bool read_only) {
1209 if (ref->not_null()) {
1210 ref->update(get_new_loc(ref));
1211 }
1212 return false; // Do not recurse.
1213 }
1214 };
1215
1216 #ifdef ASSERT
1217 class IsRefInArchiveChecker: public MetaspaceClosure {
1218 public:
1219 virtual bool do_ref(Ref* ref, bool read_only) {
1220 if (ref->not_null()) {
1221 char* obj = (char*)ref->obj();
1222 assert(_ro_region.contains(obj) || _rw_region.contains(obj),
1223 "must be relocated to point to CDS archive");
1224 }
1225 return false; // Do not recurse.
1226 }
1227 };
1228 #endif
1229
1230 public:
1231 static void copy_and_compact() {
1232 ResourceMark rm;
1233 SortedSymbolClosure the_ssc; // StackObj
1234 _ssc = &the_ssc;
1235
1236 tty->print_cr("Scanning all metaspace objects ... ");
1237 {
1238 // allocate and shallow-copy RW objects, immediately following the MC region
1239 tty->print_cr("Allocating RW objects ... ");
1240 _mc_region.pack(&_rw_region);
1241
1242 ResourceMark rm;
1243 ShallowCopier rw_copier(false);
1244 iterate_roots(&rw_copier);
1245 }
1246 {
1247 // allocate and shallow-copy of RO object, immediately following the RW region
1248 tty->print_cr("Allocating RO objects ... ");
1249 _rw_region.pack(&_ro_region);
1250
1251 ResourceMark rm;
1252 ShallowCopier ro_copier(true);
1253 iterate_roots(&ro_copier);
1254 }
1255 {
1256 tty->print_cr("Relocating embedded pointers ... ");
1257 ResourceMark rm;
1258 ShallowCopyEmbeddedRefRelocator emb_reloc;
1259 iterate_roots(&emb_reloc);
1260 }
1261 {
1262 tty->print_cr("Relocating external roots ... ");
1263 ResourceMark rm;
1264 RefRelocator ext_reloc;
1265 iterate_roots(&ext_reloc);
1266 }
1267
1268 #ifdef ASSERT
1269 {
1270 tty->print_cr("Verifying external roots ... ");
1271 ResourceMark rm;
1272 IsRefInArchiveChecker checker;
1273 iterate_roots(&checker);
1274 }
1275 #endif
1276
1277
1278 // cleanup
1279 _ssc = NULL;
1280 }
1281
1282 // We must relocate the System::_well_known_klasses only after we have copied the
1283 // java objects in during dump_java_heap_objects(): during the object copy, we operate on
1284 // old objects which assert that their klass is the original klass.
1285 static void relocate_well_known_klasses() {
1286 {
1287 tty->print_cr("Relocating SystemDictionary::_well_known_klasses[] ... ");
1288 ResourceMark rm;
1289 RefRelocator ext_reloc;
1290 SystemDictionary::well_known_klasses_do(&ext_reloc);
1291 }
1292 // NOTE: after this point, we shouldn't have any globals that can reach the old
1293 // objects.
1294
1295 // We cannot use any of the objects in the heap anymore (except for the
1296 // shared strings) because their headers no longer point to valid Klasses.
1297 }
1298
1299 static void iterate_roots(MetaspaceClosure* it) {
1300 GrowableArray<Symbol*>* symbols = _ssc->get_sorted_symbols();
1301 for (int i=0; i<symbols->length(); i++) {
1302 it->push(symbols->adr_at(i));
1303 }
1304 if (_global_klass_objects != NULL) {
1305 // Need to fix up the pointers
1306 for (int i = 0; i < _global_klass_objects->length(); i++) {
1307 // NOTE -- this requires that the vtable is NOT yet patched, or else we are hosed.
1308 it->push(_global_klass_objects->adr_at(i));
1309 }
1310 }
1311 FileMapInfo::metaspace_pointers_do(it);
1312 SystemDictionaryShared::dumptime_classes_do(it);
1313 Universe::metaspace_pointers_do(it);
1314 SymbolTable::metaspace_pointers_do(it);
1315 vmSymbols::metaspace_pointers_do(it);
1316 }
1317
1318 static Klass* get_relocated_klass(Klass* orig_klass) {
1319 assert(DumpSharedSpaces, "dump time only");
1320 address* pp = _new_loc_table->lookup((address)orig_klass);
1321 assert(pp != NULL, "must be");
1322 Klass* klass = (Klass*)(*pp);
1323 assert(klass->is_klass(), "must be");
1324 return klass;
1325 }
1326 };
1327
1328 DumpAllocStats* ArchiveCompactor::_alloc_stats;
1329 SortedSymbolClosure* ArchiveCompactor::_ssc;
1330 ArchiveCompactor::RelocationTable* ArchiveCompactor::_new_loc_table;
1331
1332 void VM_PopulateDumpSharedSpace::write_region(FileMapInfo* mapinfo, int region_idx,
1333 DumpRegion* dump_region, bool read_only, bool allow_exec) {
1334 mapinfo->write_region(region_idx, dump_region->base(), dump_region->used(), read_only, allow_exec);
1335 }
1336
1337 void VM_PopulateDumpSharedSpace::dump_symbols() {
1338 tty->print_cr("Dumping symbol table ...");
1339
1340 NOT_PRODUCT(SymbolTable::verify());
1341 SymbolTable::write_to_archive();
1342 }
1343
1344 char* VM_PopulateDumpSharedSpace::dump_read_only_tables() {
1345 ArchiveCompactor::OtherROAllocMark mark;
1346
1347 tty->print("Removing java_mirror ... ");
1348 if (!HeapShared::is_heap_object_archiving_allowed()) {
1349 clear_basic_type_mirrors();
1350 }
1351 remove_java_mirror_in_classes();
1352 tty->print_cr("done. ");
1353
1354 SystemDictionaryShared::write_to_archive();
1355
1356 char* start = _ro_region.top();
1357
1358 // Write the other data to the output array.
1359 WriteClosure wc(&_ro_region);
1360 MetaspaceShared::serialize(&wc);
1361
1362 // Write the bitmaps for patching the archive heap regions
1363 dump_archive_heap_oopmaps();
1364
1365 return start;
1366 }
1367
1368 void VM_PopulateDumpSharedSpace::doit() {
1369 // We should no longer allocate anything from the metaspace, so that:
1370 //
1371 // (1) Metaspace::allocate might trigger GC if we have run out of
1372 // committed metaspace, but we can't GC because we're running
1373 // in the VM thread.
1374 // (2) ArchiveCompactor needs to work with a stable set of MetaspaceObjs.
1375 Metaspace::freeze();
1376
1377 Thread* THREAD = VMThread::vm_thread();
1378
1379 FileMapInfo::check_nonempty_dir_in_shared_path_table();
1380
1381 NOT_PRODUCT(SystemDictionary::verify();)
1382 // The following guarantee is meant to ensure that no loader constraints
1383 // exist yet, since the constraints table is not shared. This becomes
1384 // more important now that we don't re-initialize vtables/itables for
1385 // shared classes at runtime, where constraints were previously created.
1386 guarantee(SystemDictionary::constraints()->number_of_entries() == 0,
1387 "loader constraints are not saved");
1388 guarantee(SystemDictionary::placeholders()->number_of_entries() == 0,
1389 "placeholders are not saved");
1390
1391 // At this point, many classes have been loaded.
1392 // Gather systemDictionary classes in a global array and do everything to
1393 // that so we don't have to walk the SystemDictionary again.
1394 SystemDictionaryShared::check_excluded_classes();
1395 _global_klass_objects = new GrowableArray<Klass*>(1000);
1396 CollectClassesClosure collect_classes;
1397 ClassLoaderDataGraph::loaded_classes_do(&collect_classes);
1398
1399 tty->print_cr("Number of classes %d", _global_klass_objects->length());
1400 {
1401 int num_type_array = 0, num_obj_array = 0, num_inst = 0;
1402 for (int i = 0; i < _global_klass_objects->length(); i++) {
1403 Klass* k = _global_klass_objects->at(i);
1404 if (k->is_instance_klass()) {
1405 num_inst ++;
1406 } else if (k->is_objArray_klass()) {
1407 num_obj_array ++;
1408 } else {
1409 assert(k->is_typeArray_klass(), "sanity");
1410 num_type_array ++;
1411 }
1412 }
1413 tty->print_cr(" instance classes = %5d", num_inst);
1414 tty->print_cr(" obj array classes = %5d", num_obj_array);
1415 tty->print_cr(" type array classes = %5d", num_type_array);
1416 }
1417
1418 // Ensure the ConstMethods won't be modified at run-time
1419 tty->print("Updating ConstMethods ... ");
1420 rewrite_nofast_bytecodes_and_calculate_fingerprints();
1421 tty->print_cr("done. ");
1422
1423 // Remove all references outside the metadata
1424 tty->print("Removing unshareable information ... ");
1425 remove_unshareable_in_classes();
1426 tty->print_cr("done. ");
1427
1428 ArchiveCompactor::initialize();
1429 ArchiveCompactor::copy_and_compact();
1430
1431 dump_symbols();
1432
1433 // Dump supported java heap objects
1434 _closed_archive_heap_regions = NULL;
1435 _open_archive_heap_regions = NULL;
1436 dump_java_heap_objects();
1437
1438 ArchiveCompactor::relocate_well_known_klasses();
1439
1440 char* read_only_tables_start = dump_read_only_tables();
1441 _ro_region.pack(&_md_region);
1442
1443 char* vtbl_list = _md_region.top();
1444 MetaspaceShared::allocate_cpp_vtable_clones();
1445 _md_region.pack(&_od_region);
1446
1447 // Relocate the archived class file data into the od region
1448 relocate_cached_class_file();
1449 _od_region.pack();
1450
1451 // The 5 core spaces are allocated consecutively mc->rw->ro->md->od, so there total size
1452 // is just the spaces between the two ends.
1453 size_t core_spaces_size = _od_region.end() - _mc_region.base();
1454 assert(core_spaces_size == (size_t)align_up(core_spaces_size, Metaspace::reserve_alignment()),
1455 "should already be aligned");
1456
1457 // During patching, some virtual methods may be called, so at this point
1458 // the vtables must contain valid methods (as filled in by CppVtableCloner::allocate).
1459 MetaspaceShared::patch_cpp_vtable_pointers();
1460
1461 // The vtable clones contain addresses of the current process.
1462 // We don't want to write these addresses into the archive.
1463 MetaspaceShared::zero_cpp_vtable_clones_for_writing();
1464
1465 // Create and write the archive file that maps the shared spaces.
1466
1467 FileMapInfo* mapinfo = new FileMapInfo();
1468 mapinfo->populate_header(os::vm_allocation_granularity());
1469 mapinfo->set_read_only_tables_start(read_only_tables_start);
1470 mapinfo->set_misc_data_patching_start(vtbl_list);
1471 mapinfo->set_cds_i2i_entry_code_buffers(MetaspaceShared::cds_i2i_entry_code_buffers());
1472 mapinfo->set_cds_i2i_entry_code_buffers_size(MetaspaceShared::cds_i2i_entry_code_buffers_size());
1473 mapinfo->set_core_spaces_size(core_spaces_size);
1474
1475 for (int pass=1; pass<=2; pass++) {
1476 bool print_archive_log = (pass==1);
1477 if (pass == 1) {
1478 // The first pass doesn't actually write the data to disk. All it
1479 // does is to update the fields in the mapinfo->_header.
1480 } else {
1481 // After the first pass, the contents of mapinfo->_header are finalized,
1482 // so we can compute the header's CRC, and write the contents of the header
1483 // and the regions into disk.
1484 mapinfo->open_for_write();
1485 mapinfo->set_header_crc(mapinfo->compute_header_crc());
1486 }
1487 mapinfo->write_header();
1488
1489 // NOTE: md contains the trampoline code for method entries, which are patched at run time,
1490 // so it needs to be read/write.
1491 write_region(mapinfo, MetaspaceShared::mc, &_mc_region, /*read_only=*/false,/*allow_exec=*/true);
1492 write_region(mapinfo, MetaspaceShared::rw, &_rw_region, /*read_only=*/false,/*allow_exec=*/false);
1493 write_region(mapinfo, MetaspaceShared::ro, &_ro_region, /*read_only=*/true, /*allow_exec=*/false);
1494 write_region(mapinfo, MetaspaceShared::md, &_md_region, /*read_only=*/false,/*allow_exec=*/false);
1495 write_region(mapinfo, MetaspaceShared::od, &_od_region, /*read_only=*/true, /*allow_exec=*/false);
1496
1497 _total_closed_archive_region_size = mapinfo->write_archive_heap_regions(
1498 _closed_archive_heap_regions,
1499 _closed_archive_heap_oopmaps,
1500 MetaspaceShared::first_closed_archive_heap_region,
1501 MetaspaceShared::max_closed_archive_heap_region,
1502 print_archive_log);
1503 _total_open_archive_region_size = mapinfo->write_archive_heap_regions(
1504 _open_archive_heap_regions,
1505 _open_archive_heap_oopmaps,
1506 MetaspaceShared::first_open_archive_heap_region,
1507 MetaspaceShared::max_open_archive_heap_region,
1508 print_archive_log);
1509 }
1510
1511 mapinfo->close();
1512
1513 // Restore the vtable in case we invoke any virtual methods.
1514 MetaspaceShared::clone_cpp_vtables((intptr_t*)vtbl_list);
1515
1516 print_region_stats();
1517
1518 if (log_is_enabled(Info, cds)) {
1519 ArchiveCompactor::alloc_stats()->print_stats(int(_ro_region.used()), int(_rw_region.used()),
1520 int(_mc_region.used()), int(_md_region.used()));
1521 }
1522
1523 if (PrintSystemDictionaryAtExit) {
1524 SystemDictionary::print();
1525 }
1526
1527 if (AllowArchivingWithJavaAgent) {
1528 warning("This archive was created with AllowArchivingWithJavaAgent. It should be used "
1529 "for testing purposes only and should not be used in a production environment");
1530 }
1531
1532 // There may be other pending VM operations that operate on the InstanceKlasses,
1533 // which will fail because InstanceKlasses::remove_unshareable_info()
1534 // has been called. Forget these operations and exit the VM directly.
1535 vm_direct_exit(0);
1536 }
1537
1538 void VM_PopulateDumpSharedSpace::print_region_stats() {
1539 // Print statistics of all the regions
1540 const size_t total_reserved = _ro_region.reserved() + _rw_region.reserved() +
1541 _mc_region.reserved() + _md_region.reserved() +
1542 _od_region.reserved() +
1543 _total_closed_archive_region_size +
1544 _total_open_archive_region_size;
1545 const size_t total_bytes = _ro_region.used() + _rw_region.used() +
1546 _mc_region.used() + _md_region.used() +
1547 _od_region.used() +
1548 _total_closed_archive_region_size +
1549 _total_open_archive_region_size;
1550 const double total_u_perc = percent_of(total_bytes, total_reserved);
1551
1552 _mc_region.print(total_reserved);
1553 _rw_region.print(total_reserved);
1554 _ro_region.print(total_reserved);
1555 _md_region.print(total_reserved);
1556 _od_region.print(total_reserved);
1557 print_heap_region_stats(_closed_archive_heap_regions, "ca", total_reserved);
1558 print_heap_region_stats(_open_archive_heap_regions, "oa", total_reserved);
1559
1560 tty->print_cr("total : " SIZE_FORMAT_W(9) " [100.0%% of total] out of " SIZE_FORMAT_W(9) " bytes [%5.1f%% used]",
1561 total_bytes, total_reserved, total_u_perc);
1562 }
1563
1564 void VM_PopulateDumpSharedSpace::print_heap_region_stats(GrowableArray<MemRegion> *heap_mem,
1565 const char *name, const size_t total_size) {
1566 int arr_len = heap_mem == NULL ? 0 : heap_mem->length();
1567 for (int i = 0; i < arr_len; i++) {
1568 char* start = (char*)heap_mem->at(i).start();
1569 size_t size = heap_mem->at(i).byte_size();
1570 char* top = start + size;
1571 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,
1572 name, i, size, size/double(total_size)*100.0, size, p2i(start));
1573
1574 }
1575 }
1576
1577 // Update a Java object to point its Klass* to the new location after
1578 // shared archive has been compacted.
1579 void MetaspaceShared::relocate_klass_ptr(oop o) {
1580 assert(DumpSharedSpaces, "sanity");
1581 Klass* k = ArchiveCompactor::get_relocated_klass(o->klass());
1582 o->set_klass(k);
1583 }
1584
1585 Klass* MetaspaceShared::get_relocated_klass(Klass *k) {
1586 assert(DumpSharedSpaces, "sanity");
1587 return ArchiveCompactor::get_relocated_klass(k);
1588 }
1589
1590 class LinkSharedClassesClosure : public KlassClosure {
1591 Thread* THREAD;
1592 bool _made_progress;
1593 public:
1594 LinkSharedClassesClosure(Thread* thread) : THREAD(thread), _made_progress(false) {}
1595
1596 void reset() { _made_progress = false; }
1597 bool made_progress() const { return _made_progress; }
1598
1599 void do_klass(Klass* k) {
1600 if (k->is_instance_klass()) {
1601 InstanceKlass* ik = InstanceKlass::cast(k);
1602 // Link the class to cause the bytecodes to be rewritten and the
1603 // cpcache to be created. Class verification is done according
1604 // to -Xverify setting.
1605 _made_progress |= MetaspaceShared::try_link_class(ik, THREAD);
1606 guarantee(!HAS_PENDING_EXCEPTION, "exception in link_class");
1607
1608 ik->constants()->resolve_class_constants(THREAD);
1609 }
1610 }
1611 };
1612
1613 class CheckSharedClassesClosure : public KlassClosure {
1614 bool _made_progress;
1615 public:
1616 CheckSharedClassesClosure() : _made_progress(false) {}
1617
1618 void reset() { _made_progress = false; }
1619 bool made_progress() const { return _made_progress; }
1620 void do_klass(Klass* k) {
1621 if (k->is_instance_klass() && InstanceKlass::cast(k)->check_sharing_error_state()) {
1622 _made_progress = true;
1623 }
1624 }
1625 };
1626
1627 void MetaspaceShared::link_and_cleanup_shared_classes(TRAPS) {
1628 // We need to iterate because verification may cause additional classes
1629 // to be loaded.
1630 LinkSharedClassesClosure link_closure(THREAD);
1631 do {
1632 link_closure.reset();
1633 ClassLoaderDataGraph::unlocked_loaded_classes_do(&link_closure);
1634 guarantee(!HAS_PENDING_EXCEPTION, "exception in link_class");
1635 } while (link_closure.made_progress());
1636
1637 if (_has_error_classes) {
1638 // Mark all classes whose super class or interfaces failed verification.
1639 CheckSharedClassesClosure check_closure;
1640 do {
1641 // Not completely sure if we need to do this iteratively. Anyway,
1642 // we should come here only if there are unverifiable classes, which
1643 // shouldn't happen in normal cases. So better safe than sorry.
1644 check_closure.reset();
1645 ClassLoaderDataGraph::unlocked_loaded_classes_do(&check_closure);
1646 } while (check_closure.made_progress());
1647 }
1648 }
1649
1650 void MetaspaceShared::prepare_for_dumping() {
1651 Arguments::check_unsupported_dumping_properties();
1652 ClassLoader::initialize_shared_path();
1653 }
1654
1655 // Preload classes from a list, populate the shared spaces and dump to a
1656 // file.
1657 void MetaspaceShared::preload_and_dump(TRAPS) {
1658 { TraceTime timer("Dump Shared Spaces", TRACETIME_LOG(Info, startuptime));
1659 ResourceMark rm;
1660 char class_list_path_str[JVM_MAXPATHLEN];
1661 // Preload classes to be shared.
1662 // Should use some os:: method rather than fopen() here. aB.
1663 const char* class_list_path;
1664 if (SharedClassListFile == NULL) {
1665 // Construct the path to the class list (in jre/lib)
1666 // Walk up two directories from the location of the VM and
1667 // optionally tack on "lib" (depending on platform)
1668 os::jvm_path(class_list_path_str, sizeof(class_list_path_str));
1669 for (int i = 0; i < 3; i++) {
1670 char *end = strrchr(class_list_path_str, *os::file_separator());
1671 if (end != NULL) *end = '\0';
1672 }
1673 int class_list_path_len = (int)strlen(class_list_path_str);
1674 if (class_list_path_len >= 3) {
1675 if (strcmp(class_list_path_str + class_list_path_len - 3, "lib") != 0) {
1676 if (class_list_path_len < JVM_MAXPATHLEN - 4) {
1677 jio_snprintf(class_list_path_str + class_list_path_len,
1678 sizeof(class_list_path_str) - class_list_path_len,
1679 "%slib", os::file_separator());
1680 class_list_path_len += 4;
1681 }
1682 }
1683 }
1684 if (class_list_path_len < JVM_MAXPATHLEN - 10) {
1685 jio_snprintf(class_list_path_str + class_list_path_len,
1686 sizeof(class_list_path_str) - class_list_path_len,
1687 "%sclasslist", os::file_separator());
1688 }
1689 class_list_path = class_list_path_str;
1690 } else {
1691 class_list_path = SharedClassListFile;
1692 }
1693
1694 tty->print_cr("Loading classes to share ...");
1695 _has_error_classes = false;
1696 int class_count = preload_classes(class_list_path, THREAD);
1697 if (ExtraSharedClassListFile) {
1698 class_count += preload_classes(ExtraSharedClassListFile, THREAD);
1699 }
1700 tty->print_cr("Loading classes to share: done.");
1701
1702 log_info(cds)("Shared spaces: preloaded %d classes", class_count);
1703
1704 if (SharedArchiveConfigFile) {
1705 tty->print_cr("Reading extra data from %s ...", SharedArchiveConfigFile);
1706 read_extra_data(SharedArchiveConfigFile, THREAD);
1707 }
1708 tty->print_cr("Reading extra data: done.");
1709
1710 HeapShared::init_subgraph_entry_fields(THREAD);
1711
1712 // Rewrite and link classes
1713 tty->print_cr("Rewriting and linking classes ...");
1714
1715 // Link any classes which got missed. This would happen if we have loaded classes that
1716 // were not explicitly specified in the classlist. E.g., if an interface implemented by class K
1717 // fails verification, all other interfaces that were not specified in the classlist but
1718 // are implemented by K are not verified.
1719 link_and_cleanup_shared_classes(CATCH);
1720 tty->print_cr("Rewriting and linking classes: done");
1721
1722 if (HeapShared::is_heap_object_archiving_allowed()) {
1723 // Avoid fragmentation while archiving heap objects.
1724 Universe::heap()->soft_ref_policy()->set_should_clear_all_soft_refs(true);
1725 Universe::heap()->collect(GCCause::_archive_time_gc);
1726 Universe::heap()->soft_ref_policy()->set_should_clear_all_soft_refs(false);
1727 }
1728
1729 VM_PopulateDumpSharedSpace op;
1730 VMThread::execute(&op);
1731 }
1732 }
1733
1734
1735 int MetaspaceShared::preload_classes(const char* class_list_path, TRAPS) {
1736 ClassListParser parser(class_list_path);
1737 int class_count = 0;
1738
1739 while (parser.parse_one_line()) {
1740 Klass* klass = parser.load_current_class(THREAD);
1741 if (HAS_PENDING_EXCEPTION) {
1742 if (klass == NULL &&
1743 (PENDING_EXCEPTION->klass()->name() == vmSymbols::java_lang_ClassNotFoundException())) {
1744 // print a warning only when the pending exception is class not found
1745 tty->print_cr("Preload Warning: Cannot find %s", parser.current_class_name());
1746 }
1747 CLEAR_PENDING_EXCEPTION;
1748 }
1749 if (klass != NULL) {
1750 if (log_is_enabled(Trace, cds)) {
1751 ResourceMark rm;
1752 log_trace(cds)("Shared spaces preloaded: %s", klass->external_name());
1753 }
1754
1755 if (klass->is_instance_klass()) {
1756 InstanceKlass* ik = InstanceKlass::cast(klass);
1757
1758 // Link the class to cause the bytecodes to be rewritten and the
1759 // cpcache to be created. The linking is done as soon as classes
1760 // are loaded in order that the related data structures (klass and
1761 // cpCache) are located together.
1762 try_link_class(ik, THREAD);
1763 guarantee(!HAS_PENDING_EXCEPTION, "exception in link_class");
1764 }
1765
1766 class_count++;
1767 }
1768 }
1769
1770 return class_count;
1771 }
1772
1773 // Returns true if the class's status has changed
1774 bool MetaspaceShared::try_link_class(InstanceKlass* ik, TRAPS) {
1775 assert(DumpSharedSpaces, "should only be called during dumping");
1776 if (ik->init_state() < InstanceKlass::linked) {
1777 bool saved = BytecodeVerificationLocal;
1778 if (ik->loader_type() == 0 && ik->class_loader() == NULL) {
1779 // The verification decision is based on BytecodeVerificationRemote
1780 // for non-system classes. Since we are using the NULL classloader
1781 // to load non-system classes for customized class loaders during dumping,
1782 // we need to temporarily change BytecodeVerificationLocal to be the same as
1783 // BytecodeVerificationRemote. Note this can cause the parent system
1784 // classes also being verified. The extra overhead is acceptable during
1785 // dumping.
1786 BytecodeVerificationLocal = BytecodeVerificationRemote;
1787 }
1788 ik->link_class(THREAD);
1789 if (HAS_PENDING_EXCEPTION) {
1790 ResourceMark rm;
1791 tty->print_cr("Preload Warning: Verification failed for %s",
1792 ik->external_name());
1793 CLEAR_PENDING_EXCEPTION;
1794 ik->set_in_error_state();
1795 _has_error_classes = true;
1796 }
1797 BytecodeVerificationLocal = saved;
1798 return true;
1799 } else {
1800 return false;
1801 }
1802 }
1803
1804 #if INCLUDE_CDS_JAVA_HEAP
1805 void VM_PopulateDumpSharedSpace::dump_java_heap_objects() {
1806 // The closed and open archive heap space has maximum two regions.
1807 // See FileMapInfo::write_archive_heap_regions() for details.
1808 _closed_archive_heap_regions = new GrowableArray<MemRegion>(2);
1809 _open_archive_heap_regions = new GrowableArray<MemRegion>(2);
1810 HeapShared::archive_java_heap_objects(_closed_archive_heap_regions,
1811 _open_archive_heap_regions);
1812 ArchiveCompactor::OtherROAllocMark mark;
1813 HeapShared::write_subgraph_info_table();
1814 }
1815
1816 void VM_PopulateDumpSharedSpace::dump_archive_heap_oopmaps() {
1817 if (HeapShared::is_heap_object_archiving_allowed()) {
1818 _closed_archive_heap_oopmaps = new GrowableArray<ArchiveHeapOopmapInfo>(2);
1819 dump_archive_heap_oopmaps(_closed_archive_heap_regions, _closed_archive_heap_oopmaps);
1820
1821 _open_archive_heap_oopmaps = new GrowableArray<ArchiveHeapOopmapInfo>(2);
1822 dump_archive_heap_oopmaps(_open_archive_heap_regions, _open_archive_heap_oopmaps);
1823 }
1824 }
1825
1826 void VM_PopulateDumpSharedSpace::dump_archive_heap_oopmaps(GrowableArray<MemRegion>* regions,
1827 GrowableArray<ArchiveHeapOopmapInfo>* oopmaps) {
1828 for (int i=0; i<regions->length(); i++) {
1829 ResourceBitMap oopmap = HeapShared::calculate_oopmap(regions->at(i));
1830 size_t size_in_bits = oopmap.size();
1831 size_t size_in_bytes = oopmap.size_in_bytes();
1832 uintptr_t* buffer = (uintptr_t*)_ro_region.allocate(size_in_bytes, sizeof(intptr_t));
1833 oopmap.write_to(buffer, size_in_bytes);
1834 log_info(cds)("Oopmap = " INTPTR_FORMAT " (" SIZE_FORMAT_W(6) " bytes) for heap region "
1835 INTPTR_FORMAT " (" SIZE_FORMAT_W(8) " bytes)",
1836 p2i(buffer), size_in_bytes,
1837 p2i(regions->at(i).start()), regions->at(i).byte_size());
1838
1839 ArchiveHeapOopmapInfo info;
1840 info._oopmap = (address)buffer;
1841 info._oopmap_size_in_bits = size_in_bits;
1842 oopmaps->append(info);
1843 }
1844 }
1845 #endif // INCLUDE_CDS_JAVA_HEAP
1846
1847 // Closure for serializing initialization data in from a data area
1848 // (ptr_array) read from the shared file.
1849
1850 class ReadClosure : public SerializeClosure {
1851 private:
1852 intptr_t** _ptr_array;
1853
1854 inline intptr_t nextPtr() {
1855 return *(*_ptr_array)++;
1856 }
1857
1858 public:
1859 ReadClosure(intptr_t** ptr_array) { _ptr_array = ptr_array; }
1860
1861 void do_ptr(void** p) {
1862 assert(*p == NULL, "initializing previous initialized pointer.");
1863 intptr_t obj = nextPtr();
1864 assert((intptr_t)obj >= 0 || (intptr_t)obj < -100,
1865 "hit tag while initializing ptrs.");
1866 *p = (void*)obj;
1867 }
1868
1869 void do_u4(u4* p) {
1870 intptr_t obj = nextPtr();
1871 *p = (u4)(uintx(obj));
1872 }
1873
1874 void do_tag(int tag) {
1875 int old_tag;
1876 old_tag = (int)(intptr_t)nextPtr();
1877 // do_int(&old_tag);
1878 assert(tag == old_tag, "old tag doesn't match");
1879 FileMapInfo::assert_mark(tag == old_tag);
1880 }
1881
1882 void do_oop(oop *p) {
1883 narrowOop o = (narrowOop)nextPtr();
1884 if (o == 0 || !HeapShared::open_archive_heap_region_mapped()) {
1885 p = NULL;
1886 } else {
1887 assert(HeapShared::is_heap_object_archiving_allowed(),
1888 "Archived heap object is not allowed");
1889 assert(HeapShared::open_archive_heap_region_mapped(),
1890 "Open archive heap region is not mapped");
1891 *p = HeapShared::decode_from_archive(o);
1892 }
1893 }
1894
1895 void do_region(u_char* start, size_t size) {
1896 assert((intptr_t)start % sizeof(intptr_t) == 0, "bad alignment");
1897 assert(size % sizeof(intptr_t) == 0, "bad size");
1898 do_tag((int)size);
1899 while (size > 0) {
1900 *(intptr_t*)start = nextPtr();
1901 start += sizeof(intptr_t);
1902 size -= sizeof(intptr_t);
1903 }
1904 }
1905
1906 bool reading() const { return true; }
1907 };
1908
1909 // Return true if given address is in the misc data region
1910 bool MetaspaceShared::is_in_shared_region(const void* p, int idx) {
1911 return UseSharedSpaces && FileMapInfo::current_info()->is_in_shared_region(p, idx);
1912 }
1913
1914 bool MetaspaceShared::is_in_trampoline_frame(address addr) {
1915 if (UseSharedSpaces && is_in_shared_region(addr, MetaspaceShared::mc)) {
1916 return true;
1917 }
1918 return false;
1919 }
1920
1921 // Map shared spaces at requested addresses and return if succeeded.
1922 bool MetaspaceShared::map_shared_spaces(FileMapInfo* mapinfo) {
1923 size_t image_alignment = mapinfo->alignment();
1924
1925 #ifndef _WINDOWS
1926 // Map in the shared memory and then map the regions on top of it.
1927 // On Windows, don't map the memory here because it will cause the
1928 // mappings of the regions to fail.
1929 ReservedSpace shared_rs = mapinfo->reserve_shared_memory();
1930 if (!shared_rs.is_reserved()) return false;
1931 #endif
1932
1933 assert(!DumpSharedSpaces, "Should not be called with DumpSharedSpaces");
1934
1935 char* ro_base = NULL; char* ro_top;
1936 char* rw_base = NULL; char* rw_top;
1937 char* mc_base = NULL; char* mc_top;
1938 char* md_base = NULL; char* md_top;
1939 char* od_base = NULL; char* od_top;
1940
1941 // Map each shared region
1942 if ((mc_base = mapinfo->map_region(mc, &mc_top)) != NULL &&
1943 (rw_base = mapinfo->map_region(rw, &rw_top)) != NULL &&
1944 (ro_base = mapinfo->map_region(ro, &ro_top)) != NULL &&
1945 (md_base = mapinfo->map_region(md, &md_top)) != NULL &&
1946 (od_base = mapinfo->map_region(od, &od_top)) != NULL &&
1947 (image_alignment == (size_t)os::vm_allocation_granularity()) &&
1948 mapinfo->validate_shared_path_table()) {
1949 // Success -- set up MetaspaceObj::_shared_metaspace_{base,top} for
1950 // fast checking in MetaspaceShared::is_in_shared_metaspace() and
1951 // MetaspaceObj::is_shared().
1952 //
1953 // We require that mc->rw->ro->md->od to be laid out consecutively, with no
1954 // gaps between them. That way, we can ensure that the OS won't be able to
1955 // allocate any new memory spaces inside _shared_metaspace_{base,top}, which
1956 // would mess up the simple comparision in MetaspaceShared::is_in_shared_metaspace().
1957 assert(mc_base < ro_base && mc_base < rw_base && mc_base < md_base && mc_base < od_base, "must be");
1958 assert(od_top > ro_top && od_top > rw_top && od_top > md_top && od_top > mc_top , "must be");
1959 assert(mc_top == rw_base, "must be");
1960 assert(rw_top == ro_base, "must be");
1961 assert(ro_top == md_base, "must be");
1962 assert(md_top == od_base, "must be");
1963
1964 _core_spaces_size = mapinfo->core_spaces_size();
1965 MetaspaceObj::set_shared_metaspace_range((void*)mc_base, (void*)od_top);
1966 return true;
1967 } else {
1968 // If there was a failure in mapping any of the spaces, unmap the ones
1969 // that succeeded
1970 if (ro_base != NULL) mapinfo->unmap_region(ro);
1971 if (rw_base != NULL) mapinfo->unmap_region(rw);
1972 if (mc_base != NULL) mapinfo->unmap_region(mc);
1973 if (md_base != NULL) mapinfo->unmap_region(md);
1974 if (od_base != NULL) mapinfo->unmap_region(od);
1975 #ifndef _WINDOWS
1976 // Release the entire mapped region
1977 shared_rs.release();
1978 #endif
1979 // If -Xshare:on is specified, print out the error message and exit VM,
1980 // otherwise, set UseSharedSpaces to false and continue.
1981 if (RequireSharedSpaces || PrintSharedArchiveAndExit) {
1982 vm_exit_during_initialization("Unable to use shared archive.", "Failed map_region for using -Xshare:on.");
1983 } else {
1984 FLAG_SET_DEFAULT(UseSharedSpaces, false);
1985 }
1986 return false;
1987 }
1988 }
1989
1990 // Read the miscellaneous data from the shared file, and
1991 // serialize it out to its various destinations.
1992
1993 void MetaspaceShared::initialize_shared_spaces() {
1994 FileMapInfo *mapinfo = FileMapInfo::current_info();
1995 _cds_i2i_entry_code_buffers = mapinfo->cds_i2i_entry_code_buffers();
1996 _cds_i2i_entry_code_buffers_size = mapinfo->cds_i2i_entry_code_buffers_size();
1997 // _core_spaces_size is loaded from the shared archive immediatelly after mapping
1998 assert(_core_spaces_size == mapinfo->core_spaces_size(), "sanity");
1999 char* buffer = mapinfo->misc_data_patching_start();
2000 clone_cpp_vtables((intptr_t*)buffer);
2001
2002 // The rest of the data is now stored in the RW region
2003 buffer = mapinfo->read_only_tables_start();
2004
2005 // Verify various attributes of the archive, plus initialize the
2006 // shared string/symbol tables
2007 intptr_t* array = (intptr_t*)buffer;
2008 ReadClosure rc(&array);
2009 serialize(&rc);
2010
2011 // Initialize the run-time symbol table.
2012 SymbolTable::create_table();
2013
2014 mapinfo->patch_archived_heap_embedded_pointers();
2015
2016 // Close the mapinfo file
2017 mapinfo->close();
2018
2019 if (PrintSharedArchiveAndExit) {
2020 if (PrintSharedDictionary) {
2021 tty->print_cr("\nShared classes:\n");
2022 SystemDictionaryShared::print_on(tty);
2023 }
2024 if (_archive_loading_failed) {
2025 tty->print_cr("archive is invalid");
2026 vm_exit(1);
2027 } else {
2028 tty->print_cr("archive is valid");
2029 vm_exit(0);
2030 }
2031 }
2032 }
2033
2034 // JVM/TI RedefineClasses() support:
2035 bool MetaspaceShared::remap_shared_readonly_as_readwrite() {
2036 assert(SafepointSynchronize::is_at_safepoint(), "must be at safepoint");
2037
2038 if (UseSharedSpaces) {
2039 // remap the shared readonly space to shared readwrite, private
2040 FileMapInfo* mapinfo = FileMapInfo::current_info();
2041 if (!mapinfo->remap_shared_readonly_as_readwrite()) {
2042 return false;
2043 }
2044 _remapped_readwrite = true;
2045 }
2046 return true;
2047 }
2048
2049 void MetaspaceShared::report_out_of_space(const char* name, size_t needed_bytes) {
2050 // This is highly unlikely to happen on 64-bits because we have reserved a 4GB space.
2051 // On 32-bit we reserve only 256MB so you could run out of space with 100,000 classes
2052 // or so.
2053 _mc_region.print_out_of_space_msg(name, needed_bytes);
2054 _rw_region.print_out_of_space_msg(name, needed_bytes);
2055 _ro_region.print_out_of_space_msg(name, needed_bytes);
2056 _md_region.print_out_of_space_msg(name, needed_bytes);
2057 _od_region.print_out_of_space_msg(name, needed_bytes);
2058
2059 vm_exit_during_initialization(err_msg("Unable to allocate from '%s' region", name),
2060 "Please reduce the number of shared classes.");
2061 }