1 /*
2 * Copyright (c) 2012, 2017, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 #include "precompiled.hpp"
26 #include "jvm.h"
27 #include "classfile/classListParser.hpp"
28 #include "classfile/classLoaderExt.hpp"
29 #include "classfile/dictionary.hpp"
30 #include "classfile/loaderConstraints.hpp"
31 #include "classfile/placeholders.hpp"
32 #include "classfile/sharedClassUtil.hpp"
33 #include "classfile/symbolTable.hpp"
34 #include "classfile/stringTable.hpp"
35 #include "classfile/systemDictionary.hpp"
36 #include "classfile/systemDictionaryShared.hpp"
37 #include "code/codeCache.hpp"
38 #if INCLUDE_ALL_GCS
39 #include "gc/g1/g1Allocator.inline.hpp"
40 #include "gc/g1/g1CollectedHeap.hpp"
41 #include "gc/g1/g1SATBCardTableModRefBS.hpp"
42 #endif
43 #include "gc/shared/gcLocker.hpp"
44 #include "interpreter/bytecodeStream.hpp"
45 #include "interpreter/bytecodes.hpp"
46 #include "logging/log.hpp"
47 #include "logging/logMessage.hpp"
48 #include "memory/filemap.hpp"
49 #include "memory/metaspace.hpp"
50 #include "memory/metaspaceShared.hpp"
51 #include "memory/resourceArea.hpp"
52 #include "oops/instanceClassLoaderKlass.hpp"
53 #include "oops/instanceMirrorKlass.hpp"
54 #include "oops/instanceRefKlass.hpp"
55 #include "oops/objArrayKlass.hpp"
56 #include "oops/objArrayOop.hpp"
57 #include "oops/oop.inline.hpp"
58 #include "oops/typeArrayKlass.hpp"
59 #include "prims/jvmtiRedefineClasses.hpp"
60 #include "runtime/timerTrace.hpp"
61 #include "runtime/os.hpp"
62 #include "runtime/signature.hpp"
63 #include "runtime/vmThread.hpp"
64 #include "runtime/vm_operations.hpp"
65 #include "utilities/align.hpp"
66 #include "utilities/defaultStream.hpp"
67 #include "utilities/hashtable.inline.hpp"
68 #include "memory/metaspaceClosure.hpp"
69
70 ReservedSpace MetaspaceShared::_shared_rs;
71 VirtualSpace MetaspaceShared::_shared_vs;
72 MetaspaceSharedStats MetaspaceShared::_stats;
73 bool MetaspaceShared::_has_error_classes;
74 bool MetaspaceShared::_archive_loading_failed = false;
75 bool MetaspaceShared::_remapped_readwrite = false;
76 bool MetaspaceShared::_open_archive_heap_region_mapped = false;
77 address MetaspaceShared::_cds_i2i_entry_code_buffers = NULL;
78 size_t MetaspaceShared::_cds_i2i_entry_code_buffers_size = 0;
79 size_t MetaspaceShared::_core_spaces_size = 0;
80
81 // The CDS archive is divided into the following regions:
82 // mc - misc code (the method entry trampolines)
83 // rw - read-write metadata
84 // ro - read-only metadata and read-only tables
85 // md - misc data (the c++ vtables)
86 // od - optional data (original class files)
87 //
88 // s0 - shared strings(closed archive heap space) #0
89 // s1 - shared strings(closed archive heap space) #1 (may be empty)
90 // oa0 - open archive heap space #0
91 // oa1 - open archive heap space #1 (may be empty)
92 //
93 // The mc, rw, ro, md and od regions are linearly allocated, starting from
94 // SharedBaseAddress, in the order of mc->rw->ro->md->od. The size of these 5 regions
95 // are page-aligned, and there's no gap between any consecutive regions.
96 //
97 // These 5 regions are populated in the following steps:
98 // [1] All classes are loaded in MetaspaceShared::preload_classes(). All metadata are
99 // temporarily allocated outside of the shared regions. Only the method entry
100 // trampolines are written into the mc region.
101 // [2] ArchiveCompactor copies RW metadata into the rw region.
102 // [3] ArchiveCompactor copies RO metadata into the ro region.
103 // [4] SymbolTable, StringTable, SystemDictionary, and a few other read-only data
104 // are copied into the ro region as read-only tables.
105 // [5] C++ vtables are copied into the md region.
106 // [6] Original class files are copied into the od region.
107 //
108 // The s0/s1 and oa0/oa1 regions are populated inside MetaspaceShared::dump_java_heap_objects.
109 // Their layout is independent of the other 5 regions.
110
111 class DumpRegion {
112 private:
113 const char* _name;
114 char* _base;
115 char* _top;
116 char* _end;
117 bool _is_packed;
118
119 char* expand_top_to(char* newtop) {
120 assert(is_allocatable(), "must be initialized and not packed");
121 assert(newtop >= _top, "must not grow backwards");
122 if (newtop > _end) {
123 MetaspaceShared::report_out_of_space(_name, newtop - _top);
124 ShouldNotReachHere();
125 }
126 MetaspaceShared::commit_shared_space_to(newtop);
127 _top = newtop;
128 return _top;
129 }
130
131 public:
132 DumpRegion(const char* name) : _name(name), _base(NULL), _top(NULL), _end(NULL), _is_packed(false) {}
133
134 char* allocate(size_t num_bytes, size_t alignment=BytesPerWord) {
135 char* p = (char*)align_up(_top, alignment);
136 char* newtop = p + align_up(num_bytes, alignment);
137 expand_top_to(newtop);
138 memset(p, 0, newtop - p);
139 return p;
140 }
141
142 void append_intptr_t(intptr_t n) {
143 assert(is_aligned(_top, sizeof(intptr_t)), "bad alignment");
144 intptr_t *p = (intptr_t*)_top;
145 char* newtop = _top + sizeof(intptr_t);
146 expand_top_to(newtop);
147 *p = n;
148 }
149
150 char* base() const { return _base; }
151 char* top() const { return _top; }
152 char* end() const { return _end; }
153 size_t reserved() const { return _end - _base; }
154 size_t used() const { return _top - _base; }
155 bool is_packed() const { return _is_packed; }
156 bool is_allocatable() const {
157 return !is_packed() && _base != NULL;
158 }
159
160 void print(size_t total_bytes) const {
161 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,
162 _name, used(), percent_of(used(), total_bytes), reserved(), percent_of(used(), reserved()), p2i(_base));
163 }
164 void print_out_of_space_msg(const char* failing_region, size_t needed_bytes) {
165 tty->print("[%-8s] " PTR_FORMAT " - " PTR_FORMAT " capacity =%9d, allocated =%9d",
166 _name, p2i(_base), p2i(_top), int(_end - _base), int(_top - _base));
167 if (strcmp(_name, failing_region) == 0) {
168 tty->print_cr(" required = %d", int(needed_bytes));
169 } else {
170 tty->cr();
171 }
172 }
173
174 void init(const ReservedSpace* rs) {
175 _base = _top = rs->base();
176 _end = rs->end();
177 }
178 void init(char* b, char* t, char* e) {
179 _base = b;
180 _top = t;
181 _end = e;
182 }
183
184 void pack(DumpRegion* next = NULL) {
185 assert(!is_packed(), "sanity");
186 _end = (char*)align_up(_top, Metaspace::reserve_alignment());
187 _is_packed = true;
188 if (next != NULL) {
189 next->_base = next->_top = this->_end;
190 next->_end = MetaspaceShared::shared_rs()->end();
191 }
192 }
193 bool contains(char* p) {
194 return base() <= p && p < top();
195 }
196 };
197
198
199 DumpRegion _mc_region("mc"), _ro_region("ro"), _rw_region("rw"), _md_region("md"), _od_region("od");
200 size_t _total_string_region_size = 0, _total_open_archive_region_size = 0;
201
202 char* MetaspaceShared::misc_code_space_alloc(size_t num_bytes) {
203 return _mc_region.allocate(num_bytes);
204 }
205
206 char* MetaspaceShared::read_only_space_alloc(size_t num_bytes) {
207 return _ro_region.allocate(num_bytes);
208 }
209
210 void MetaspaceShared::initialize_runtime_shared_and_meta_spaces() {
211 assert(UseSharedSpaces, "Must be called when UseSharedSpaces is enabled");
212
213 // If using shared space, open the file that contains the shared space
214 // and map in the memory before initializing the rest of metaspace (so
215 // the addresses don't conflict)
216 address cds_address = NULL;
217 FileMapInfo* mapinfo = new FileMapInfo();
218
219 // Open the shared archive file, read and validate the header. If
220 // initialization fails, shared spaces [UseSharedSpaces] are
221 // disabled and the file is closed.
222 // Map in spaces now also
223 if (mapinfo->initialize() && map_shared_spaces(mapinfo)) {
224 size_t cds_total = core_spaces_size();
225 cds_address = (address)mapinfo->header()->region_addr(0);
226 #ifdef _LP64
227 if (Metaspace::using_class_space()) {
228 char* cds_end = (char*)(cds_address + cds_total);
229 cds_end = (char *)align_up(cds_end, Metaspace::reserve_alignment());
230 // If UseCompressedClassPointers is set then allocate the metaspace area
231 // above the heap and above the CDS area (if it exists).
232 Metaspace::allocate_metaspace_compressed_klass_ptrs(cds_end, cds_address);
233 // map_heap_regions() compares the current narrow oop and klass encodings
234 // with the archived ones, so it must be done after all encodings are determined.
235 mapinfo->map_heap_regions();
236 }
237 #endif // _LP64
238 } else {
239 assert(!mapinfo->is_open() && !UseSharedSpaces,
240 "archive file not closed or shared spaces not disabled.");
241 }
242 }
243
244 void MetaspaceShared::initialize_dumptime_shared_and_meta_spaces() {
245 assert(DumpSharedSpaces, "should be called for dump time only");
246 const size_t reserve_alignment = Metaspace::reserve_alignment();
247 bool large_pages = false; // No large pages when dumping the CDS archive.
248 char* shared_base = (char*)align_up((char*)SharedBaseAddress, reserve_alignment);
249
250 #ifdef _LP64
251 // On 64-bit VM, the heap and class space layout will be the same as if
252 // you're running in -Xshare:on mode:
253 //
254 // +-- SharedBaseAddress (default = 0x800000000)
255 // v
256 // +-..---------+---------+ ... +----+----+----+----+----+---------------+
257 // | Heap | Archive | | MC | RW | RO | MD | OD | class space |
258 // +-..---------+---------+ ... +----+----+----+----+----+---------------+
259 // |<-- MaxHeapSize -->| |<-- UnscaledClassSpaceMax = 4GB ------->|
260 //
261 const uint64_t UnscaledClassSpaceMax = (uint64_t(max_juint) + 1);
262 const size_t cds_total = align_down(UnscaledClassSpaceMax, reserve_alignment);
263 #else
264 // We don't support archives larger than 256MB on 32-bit due to limited virtual address space.
265 size_t cds_total = align_down(256*M, reserve_alignment);
266 #endif
267
268 // First try to reserve the space at the specified SharedBaseAddress.
269 _shared_rs = ReservedSpace(cds_total, reserve_alignment, large_pages, shared_base);
270 if (_shared_rs.is_reserved()) {
271 assert(shared_base == 0 || _shared_rs.base() == shared_base, "should match");
272 } else {
273 // Get a mmap region anywhere if the SharedBaseAddress fails.
274 _shared_rs = ReservedSpace(cds_total, reserve_alignment, large_pages);
275 }
276 if (!_shared_rs.is_reserved()) {
277 vm_exit_during_initialization("Unable to reserve memory for shared space",
278 err_msg(SIZE_FORMAT " bytes.", cds_total));
279 }
280
281 #ifdef _LP64
282 // During dump time, we allocate 4GB (UnscaledClassSpaceMax) of space and split it up:
283 // + The upper 1 GB is used as the "temporary compressed class space" -- preload_classes()
284 // will store Klasses into this space.
285 // + The lower 3 GB is used for the archive -- when preload_classes() is done,
286 // ArchiveCompactor will copy the class metadata into this space, first the RW parts,
287 // then the RO parts.
288
289 assert(UseCompressedOops && UseCompressedClassPointers,
290 "UseCompressedOops and UseCompressedClassPointers must be set");
291
292 size_t max_archive_size = align_down(cds_total * 3 / 4, reserve_alignment);
293 ReservedSpace tmp_class_space = _shared_rs.last_part(max_archive_size);
294 CompressedClassSpaceSize = align_down(tmp_class_space.size(), reserve_alignment);
295 _shared_rs = _shared_rs.first_part(max_archive_size);
296
297 // Set up compress class pointers.
298 Universe::set_narrow_klass_base((address)_shared_rs.base());
299 // Set narrow_klass_shift to be LogKlassAlignmentInBytes. This is consistent
300 // with AOT.
301 Universe::set_narrow_klass_shift(LogKlassAlignmentInBytes);
302
303 Metaspace::initialize_class_space(tmp_class_space);
304 tty->print_cr("narrow_klass_base = " PTR_FORMAT ", narrow_klass_shift = %d",
305 p2i(Universe::narrow_klass_base()), Universe::narrow_klass_shift());
306
307 tty->print_cr("Allocated temporary class space: " SIZE_FORMAT " bytes at " PTR_FORMAT,
308 CompressedClassSpaceSize, p2i(tmp_class_space.base()));
309 #endif
310
311 // Start with 0 committed bytes. The memory will be committed as needed by
312 // MetaspaceShared::commit_shared_space_to().
313 if (!_shared_vs.initialize(_shared_rs, 0)) {
314 vm_exit_during_initialization("Unable to allocate memory for shared space");
315 }
316
317 _mc_region.init(&_shared_rs);
318 tty->print_cr("Allocated shared space: " SIZE_FORMAT " bytes at " PTR_FORMAT,
319 _shared_rs.size(), p2i(_shared_rs.base()));
320 }
321
322 void MetaspaceShared::commit_shared_space_to(char* newtop) {
323 assert(DumpSharedSpaces, "dump-time only");
324 char* base = _shared_rs.base();
325 size_t need_committed_size = newtop - base;
326 size_t has_committed_size = _shared_vs.committed_size();
327 if (need_committed_size < has_committed_size) {
328 return;
329 }
330
331 size_t min_bytes = need_committed_size - has_committed_size;
332 size_t preferred_bytes = 1 * M;
333 size_t uncommitted = _shared_vs.reserved_size() - has_committed_size;
334
335 size_t commit = MAX2(min_bytes, preferred_bytes);
336 assert(commit <= uncommitted, "sanity");
337
338 bool result = _shared_vs.expand_by(commit, false);
339 if (!result) {
340 vm_exit_during_initialization(err_msg("Failed to expand shared space to " SIZE_FORMAT " bytes",
341 need_committed_size));
342 }
343
344 log_info(cds)("Expanding shared spaces by " SIZE_FORMAT_W(7) " bytes [total " SIZE_FORMAT_W(9) " bytes ending at %p]",
345 commit, _shared_vs.actual_committed_size(), _shared_vs.high());
346 }
347
348 // Read/write a data stream for restoring/preserving metadata pointers and
349 // miscellaneous data from/to the shared archive file.
350
351 void MetaspaceShared::serialize(SerializeClosure* soc) {
352 int tag = 0;
353 soc->do_tag(--tag);
354
355 // Verify the sizes of various metadata in the system.
356 soc->do_tag(sizeof(Method));
357 soc->do_tag(sizeof(ConstMethod));
358 soc->do_tag(arrayOopDesc::base_offset_in_bytes(T_BYTE));
359 soc->do_tag(sizeof(ConstantPool));
360 soc->do_tag(sizeof(ConstantPoolCache));
361 soc->do_tag(objArrayOopDesc::base_offset_in_bytes());
362 soc->do_tag(typeArrayOopDesc::base_offset_in_bytes(T_BYTE));
363 soc->do_tag(sizeof(Symbol));
364
365 // Dump/restore miscellaneous metadata.
366 Universe::serialize(soc, true);
367 soc->do_tag(--tag);
368
369 // Dump/restore references to commonly used names and signatures.
370 vmSymbols::serialize(soc);
371 soc->do_tag(--tag);
372
373 // Dump/restore the symbol and string tables
374 SymbolTable::serialize(soc);
375 StringTable::serialize(soc);
376 soc->do_tag(--tag);
377
378 soc->do_tag(666);
379 }
380
381 address MetaspaceShared::cds_i2i_entry_code_buffers(size_t total_size) {
382 if (DumpSharedSpaces) {
383 if (_cds_i2i_entry_code_buffers == NULL) {
384 _cds_i2i_entry_code_buffers = (address)misc_code_space_alloc(total_size);
385 _cds_i2i_entry_code_buffers_size = total_size;
386 }
387 } else if (UseSharedSpaces) {
388 assert(_cds_i2i_entry_code_buffers != NULL, "must already been initialized");
389 } else {
390 return NULL;
391 }
392
393 assert(_cds_i2i_entry_code_buffers_size == total_size, "must not change");
394 return _cds_i2i_entry_code_buffers;
395 }
396
397 // CDS code for dumping shared archive.
398
399 // Global object for holding classes that have been loaded. Since this
400 // is run at a safepoint just before exit, this is the entire set of classes.
401 static GrowableArray<Klass*>* _global_klass_objects;
402
403 static void collect_array_classes(Klass* k) {
404 _global_klass_objects->append_if_missing(k);
405 if (k->is_array_klass()) {
406 // Add in the array classes too
407 ArrayKlass* ak = ArrayKlass::cast(k);
408 Klass* h = ak->higher_dimension();
409 if (h != NULL) {
410 h->array_klasses_do(collect_array_classes);
411 }
412 }
413 }
414
415 class CollectClassesClosure : public KlassClosure {
416 void do_klass(Klass* k) {
417 if (!(k->is_instance_klass() && InstanceKlass::cast(k)->is_in_error_state())) {
418 _global_klass_objects->append_if_missing(k);
419 }
420 if (k->is_array_klass()) {
421 // Add in the array classes too
422 ArrayKlass* ak = ArrayKlass::cast(k);
423 Klass* h = ak->higher_dimension();
424 if (h != NULL) {
425 h->array_klasses_do(collect_array_classes);
426 }
427 }
428 }
429 };
430
431 static void remove_unshareable_in_classes() {
432 for (int i = 0; i < _global_klass_objects->length(); i++) {
433 Klass* k = _global_klass_objects->at(i);
434 if (!k->is_objArray_klass()) {
435 // InstanceKlass and TypeArrayKlass will in turn call remove_unshareable_info
436 // on their array classes.
437 assert(k->is_instance_klass() || k->is_typeArray_klass(), "must be");
438 k->remove_unshareable_info();
439 }
440 }
441 }
442
443 static void remove_java_mirror_in_classes() {
444 for (int i = 0; i < _global_klass_objects->length(); i++) {
445 Klass* k = _global_klass_objects->at(i);
446 if (!k->is_objArray_klass()) {
447 // InstanceKlass and TypeArrayKlass will in turn call remove_unshareable_info
448 // on their array classes.
449 assert(k->is_instance_klass() || k->is_typeArray_klass(), "must be");
450 k->remove_java_mirror();
451 }
452 }
453 }
454
455 static void rewrite_nofast_bytecode(Method* method) {
456 BytecodeStream bcs(method);
457 while (!bcs.is_last_bytecode()) {
458 Bytecodes::Code opcode = bcs.next();
459 switch (opcode) {
460 case Bytecodes::_getfield: *bcs.bcp() = Bytecodes::_nofast_getfield; break;
461 case Bytecodes::_putfield: *bcs.bcp() = Bytecodes::_nofast_putfield; break;
462 case Bytecodes::_aload_0: *bcs.bcp() = Bytecodes::_nofast_aload_0; break;
463 case Bytecodes::_iload: {
464 if (!bcs.is_wide()) {
465 *bcs.bcp() = Bytecodes::_nofast_iload;
466 }
467 break;
468 }
469 default: break;
470 }
471 }
472 }
473
474 // Walk all methods in the class list to ensure that they won't be modified at
475 // run time. This includes:
476 // [1] Rewrite all bytecodes as needed, so that the ConstMethod* will not be modified
477 // at run time by RewriteBytecodes/RewriteFrequentPairs
478 // [2] Assign a fingerprint, so one doesn't need to be assigned at run-time.
479 static void rewrite_nofast_bytecodes_and_calculate_fingerprints() {
480 for (int i = 0; i < _global_klass_objects->length(); i++) {
481 Klass* k = _global_klass_objects->at(i);
482 if (k->is_instance_klass()) {
483 InstanceKlass* ik = InstanceKlass::cast(k);
484 for (int i = 0; i < ik->methods()->length(); i++) {
485 Method* m = ik->methods()->at(i);
486 rewrite_nofast_bytecode(m);
487 Fingerprinter fp(m);
488 // The side effect of this call sets method's fingerprint field.
489 fp.fingerprint();
490 }
491 }
492 }
493 }
494
495 static void relocate_cached_class_file() {
496 for (int i = 0; i < _global_klass_objects->length(); i++) {
497 Klass* k = _global_klass_objects->at(i);
498 if (k->is_instance_klass()) {
499 InstanceKlass* ik = InstanceKlass::cast(k);
500 JvmtiCachedClassFileData* p = ik->get_archived_class_data();
501 if (p != NULL) {
502 int size = offset_of(JvmtiCachedClassFileData, data) + p->length;
503 JvmtiCachedClassFileData* q = (JvmtiCachedClassFileData*)_od_region.allocate(size);
504 q->length = p->length;
505 memcpy(q->data, p->data, p->length);
506 ik->set_archived_class_data(q);
507 }
508 }
509 }
510 }
511
512 NOT_PRODUCT(
513 static void assert_not_anonymous_class(InstanceKlass* k) {
514 assert(!(k->is_anonymous()), "cannot archive anonymous classes");
515 }
516
517 // Anonymous classes are not stored inside any dictionaries. They are created by
518 // SystemDictionary::parse_stream() with a non-null host_klass.
519 static void assert_no_anonymoys_classes_in_dictionaries() {
520 ClassLoaderDataGraph::dictionary_classes_do(assert_not_anonymous_class);
521 })
522
523 // Objects of the Metadata types (such as Klass and ConstantPool) have C++ vtables.
524 // (In GCC this is the field <Type>::_vptr, i.e., first word in the object.)
525 //
526 // Addresses of the vtables and the methods may be different across JVM runs,
527 // if libjvm.so is dynamically loaded at a different base address.
528 //
529 // To ensure that the Metadata objects in the CDS archive always have the correct vtable:
530 //
531 // + at dump time: we redirect the _vptr to point to our own vtables inside
532 // the CDS image
533 // + at run time: we clone the actual contents of the vtables from libjvm.so
534 // into our own tables.
535
536 // Currently, the archive contain ONLY the following types of objects that have C++ vtables.
537 #define CPP_VTABLE_PATCH_TYPES_DO(f) \
538 f(ConstantPool) \
539 f(InstanceKlass) \
540 f(InstanceClassLoaderKlass) \
541 f(InstanceMirrorKlass) \
542 f(InstanceRefKlass) \
543 f(Method) \
544 f(ObjArrayKlass) \
545 f(TypeArrayKlass)
546
547 class CppVtableInfo {
548 intptr_t _vtable_size;
549 intptr_t _cloned_vtable[1];
550 public:
551 static int num_slots(int vtable_size) {
552 return 1 + vtable_size; // Need to add the space occupied by _vtable_size;
553 }
554 int vtable_size() { return int(uintx(_vtable_size)); }
555 void set_vtable_size(int n) { _vtable_size = intptr_t(n); }
556 intptr_t* cloned_vtable() { return &_cloned_vtable[0]; }
557 void zero() { memset(_cloned_vtable, 0, sizeof(intptr_t) * vtable_size()); }
558 // Returns the address of the next CppVtableInfo that can be placed immediately after this CppVtableInfo
559 static size_t byte_size(int vtable_size) {
560 CppVtableInfo i;
561 return pointer_delta(&i._cloned_vtable[vtable_size], &i, sizeof(u1));
562 }
563 };
564
565 template <class T> class CppVtableCloner : public T {
566 static intptr_t* vtable_of(Metadata& m) {
567 return *((intptr_t**)&m);
568 }
569 static CppVtableInfo* _info;
570
571 static int get_vtable_length(const char* name);
572
573 public:
574 // Allocate and initialize the C++ vtable, starting from top, but do not go past end.
575 static intptr_t* allocate(const char* name);
576
577 // Clone the vtable to ...
578 static intptr_t* clone_vtable(const char* name, CppVtableInfo* info);
579
580 static void zero_vtable_clone() {
581 assert(DumpSharedSpaces, "dump-time only");
582 _info->zero();
583 }
584
585 // Switch the vtable pointer to point to the cloned vtable.
586 static void patch(Metadata* obj) {
587 assert(DumpSharedSpaces, "dump-time only");
588 *(void**)obj = (void*)(_info->cloned_vtable());
589 }
590
591 static bool is_valid_shared_object(const T* obj) {
592 intptr_t* vptr = *(intptr_t**)obj;
593 return vptr == _info->cloned_vtable();
594 }
595 };
596
597 template <class T> CppVtableInfo* CppVtableCloner<T>::_info = NULL;
598
599 template <class T>
600 intptr_t* CppVtableCloner<T>::allocate(const char* name) {
601 assert(is_aligned(_md_region.top(), sizeof(intptr_t)), "bad alignment");
602 int n = get_vtable_length(name);
603 _info = (CppVtableInfo*)_md_region.allocate(CppVtableInfo::byte_size(n), sizeof(intptr_t));
604 _info->set_vtable_size(n);
605
606 intptr_t* p = clone_vtable(name, _info);
607 assert((char*)p == _md_region.top(), "must be");
608
609 return p;
610 }
611
612 template <class T>
613 intptr_t* CppVtableCloner<T>::clone_vtable(const char* name, CppVtableInfo* info) {
614 if (!DumpSharedSpaces) {
615 assert(_info == 0, "_info is initialized only at dump time");
616 _info = info; // Remember it -- it will be used by MetaspaceShared::is_valid_shared_method()
617 }
618 T tmp; // Allocate temporary dummy metadata object to get to the original vtable.
619 int n = info->vtable_size();
620 intptr_t* srcvtable = vtable_of(tmp);
621 intptr_t* dstvtable = info->cloned_vtable();
622
623 // We already checked (and, if necessary, adjusted n) when the vtables were allocated, so we are
624 // safe to do memcpy.
625 log_debug(cds, vtables)("Copying %3d vtable entries for %s", n, name);
626 memcpy(dstvtable, srcvtable, sizeof(intptr_t) * n);
627 return dstvtable + n;
628 }
629
630 // To determine the size of the vtable for each type, we use the following
631 // trick by declaring 2 subclasses:
632 //
633 // class CppVtableTesterA: public InstanceKlass {virtual int last_virtual_method() {return 1;} };
634 // class CppVtableTesterB: public InstanceKlass {virtual void* last_virtual_method() {return NULL}; };
635 //
636 // CppVtableTesterA and CppVtableTesterB's vtables have the following properties:
637 // - Their size (N+1) is exactly one more than the size of InstanceKlass's vtable (N)
638 // - The first N entries have are exactly the same as in InstanceKlass's vtable.
639 // - Their last entry is different.
640 //
641 // So to determine the value of N, we just walk CppVtableTesterA and CppVtableTesterB's tables
642 // and find the first entry that's different.
643 //
644 // This works on all C++ compilers supported by Oracle, but you may need to tweak it for more
645 // esoteric compilers.
646
647 template <class T> class CppVtableTesterB: public T {
648 public:
649 virtual int last_virtual_method() {return 1;}
650 };
651
652 template <class T> class CppVtableTesterA : public T {
653 public:
654 virtual void* last_virtual_method() {
655 // Make this different than CppVtableTesterB::last_virtual_method so the C++
656 // compiler/linker won't alias the two functions.
657 return NULL;
658 }
659 };
660
661 template <class T>
662 int CppVtableCloner<T>::get_vtable_length(const char* name) {
663 CppVtableTesterA<T> a;
664 CppVtableTesterB<T> b;
665
666 intptr_t* avtable = vtable_of(a);
667 intptr_t* bvtable = vtable_of(b);
668
669 // Start at slot 1, because slot 0 may be RTTI (on Solaris/Sparc)
670 int vtable_len = 1;
671 for (; ; vtable_len++) {
672 if (avtable[vtable_len] != bvtable[vtable_len]) {
673 break;
674 }
675 }
676 log_debug(cds, vtables)("Found %3d vtable entries for %s", vtable_len, name);
677
678 return vtable_len;
679 }
680
681 #define ALLOC_CPP_VTABLE_CLONE(c) \
682 CppVtableCloner<c>::allocate(#c);
683
684 #define CLONE_CPP_VTABLE(c) \
685 p = CppVtableCloner<c>::clone_vtable(#c, (CppVtableInfo*)p);
686
687 #define ZERO_CPP_VTABLE(c) \
688 CppVtableCloner<c>::zero_vtable_clone();
689
690 // This can be called at both dump time and run time.
691 intptr_t* MetaspaceShared::clone_cpp_vtables(intptr_t* p) {
692 assert(DumpSharedSpaces || UseSharedSpaces, "sanity");
693 CPP_VTABLE_PATCH_TYPES_DO(CLONE_CPP_VTABLE);
694 return p;
695 }
696
697 void MetaspaceShared::zero_cpp_vtable_clones_for_writing() {
698 assert(DumpSharedSpaces, "dump-time only");
699 CPP_VTABLE_PATCH_TYPES_DO(ZERO_CPP_VTABLE);
700 }
701
702 // Allocate and initialize the C++ vtables, starting from top, but do not go past end.
703 void MetaspaceShared::allocate_cpp_vtable_clones() {
704 assert(DumpSharedSpaces, "dump-time only");
705 // Layout (each slot is a intptr_t):
706 // [number of slots in the first vtable = n1]
707 // [ <n1> slots for the first vtable]
708 // [number of slots in the first second = n2]
709 // [ <n2> slots for the second vtable]
710 // ...
711 // The order of the vtables is the same as the CPP_VTAB_PATCH_TYPES_DO macro.
712 CPP_VTABLE_PATCH_TYPES_DO(ALLOC_CPP_VTABLE_CLONE);
713 }
714
715 // Switch the vtable pointer to point to the cloned vtable. We assume the
716 // vtable pointer is in first slot in object.
717 void MetaspaceShared::patch_cpp_vtable_pointers() {
718 int n = _global_klass_objects->length();
719 for (int i = 0; i < n; i++) {
720 Klass* obj = _global_klass_objects->at(i);
721 if (obj->is_instance_klass()) {
722 InstanceKlass* ik = InstanceKlass::cast(obj);
723 if (ik->is_class_loader_instance_klass()) {
724 CppVtableCloner<InstanceClassLoaderKlass>::patch(ik);
725 } else if (ik->is_reference_instance_klass()) {
726 CppVtableCloner<InstanceRefKlass>::patch(ik);
727 } else if (ik->is_mirror_instance_klass()) {
728 CppVtableCloner<InstanceMirrorKlass>::patch(ik);
729 } else {
730 CppVtableCloner<InstanceKlass>::patch(ik);
731 }
732 ConstantPool* cp = ik->constants();
733 CppVtableCloner<ConstantPool>::patch(cp);
734 for (int j = 0; j < ik->methods()->length(); j++) {
735 Method* m = ik->methods()->at(j);
736 CppVtableCloner<Method>::patch(m);
737 assert(CppVtableCloner<Method>::is_valid_shared_object(m), "must be");
738 }
739 } else if (obj->is_objArray_klass()) {
740 CppVtableCloner<ObjArrayKlass>::patch(obj);
741 } else {
742 assert(obj->is_typeArray_klass(), "sanity");
743 CppVtableCloner<TypeArrayKlass>::patch(obj);
744 }
745 }
746 }
747
748 bool MetaspaceShared::is_valid_shared_method(const Method* m) {
749 assert(is_in_shared_space(m), "must be");
750 return CppVtableCloner<Method>::is_valid_shared_object(m);
751 }
752
753 // Closure for serializing initialization data out to a data area to be
754 // written to the shared file.
755
756 class WriteClosure : public SerializeClosure {
757 private:
758 DumpRegion* _dump_region;
759
760 public:
761 WriteClosure(DumpRegion* r) {
762 _dump_region = r;
763 }
764
765 void do_ptr(void** p) {
766 _dump_region->append_intptr_t((intptr_t)*p);
767 }
768
769 void do_u4(u4* p) {
770 void* ptr = (void*)(uintx(*p));
771 do_ptr(&ptr);
772 }
773
774 void do_tag(int tag) {
775 _dump_region->append_intptr_t((intptr_t)tag);
776 }
777
778 void do_region(u_char* start, size_t size) {
779 assert((intptr_t)start % sizeof(intptr_t) == 0, "bad alignment");
780 assert(size % sizeof(intptr_t) == 0, "bad size");
781 do_tag((int)size);
782 while (size > 0) {
783 _dump_region->append_intptr_t(*(intptr_t*)start);
784 start += sizeof(intptr_t);
785 size -= sizeof(intptr_t);
786 }
787 }
788
789 bool reading() const { return false; }
790 };
791
792 // This is for dumping detailed statistics for the allocations
793 // in the shared spaces.
794 class DumpAllocStats : public ResourceObj {
795 public:
796
797 // Here's poor man's enum inheritance
798 #define SHAREDSPACE_OBJ_TYPES_DO(f) \
799 METASPACE_OBJ_TYPES_DO(f) \
800 f(SymbolHashentry) \
801 f(SymbolBucket) \
802 f(StringHashentry) \
803 f(StringBucket) \
804 f(Other)
805
806 enum Type {
807 // Types are MetaspaceObj::ClassType, MetaspaceObj::SymbolType, etc
808 SHAREDSPACE_OBJ_TYPES_DO(METASPACE_OBJ_TYPE_DECLARE)
809 _number_of_types
810 };
811
812 static const char * type_name(Type type) {
813 switch(type) {
814 SHAREDSPACE_OBJ_TYPES_DO(METASPACE_OBJ_TYPE_NAME_CASE)
815 default:
816 ShouldNotReachHere();
817 return NULL;
818 }
819 }
820
821 public:
822 enum { RO = 0, RW = 1 };
823
824 int _counts[2][_number_of_types];
825 int _bytes [2][_number_of_types];
826
827 DumpAllocStats() {
828 memset(_counts, 0, sizeof(_counts));
829 memset(_bytes, 0, sizeof(_bytes));
830 };
831
832 void record(MetaspaceObj::Type type, int byte_size, bool read_only) {
833 assert(int(type) >= 0 && type < MetaspaceObj::_number_of_types, "sanity");
834 int which = (read_only) ? RO : RW;
835 _counts[which][type] ++;
836 _bytes [which][type] += byte_size;
837 }
838
839 void record_other_type(int byte_size, bool read_only) {
840 int which = (read_only) ? RO : RW;
841 _bytes [which][OtherType] += byte_size;
842 }
843 void print_stats(int ro_all, int rw_all, int mc_all, int md_all);
844 };
845
846 void DumpAllocStats::print_stats(int ro_all, int rw_all, int mc_all, int md_all) {
847 // Calculate size of data that was not allocated by Metaspace::allocate()
848 MetaspaceSharedStats *stats = MetaspaceShared::stats();
849
850 // symbols
851 _counts[RO][SymbolHashentryType] = stats->symbol.hashentry_count;
852 _bytes [RO][SymbolHashentryType] = stats->symbol.hashentry_bytes;
853
854 _counts[RO][SymbolBucketType] = stats->symbol.bucket_count;
855 _bytes [RO][SymbolBucketType] = stats->symbol.bucket_bytes;
856
857 // strings
858 _counts[RO][StringHashentryType] = stats->string.hashentry_count;
859 _bytes [RO][StringHashentryType] = stats->string.hashentry_bytes;
860
861 _counts[RO][StringBucketType] = stats->string.bucket_count;
862 _bytes [RO][StringBucketType] = stats->string.bucket_bytes;
863
864 // TODO: count things like dictionary, vtable, etc
865 _bytes[RW][OtherType] += mc_all + md_all;
866 rw_all += mc_all + md_all; // mc/md are mapped Read/Write
867
868 // prevent divide-by-zero
869 if (ro_all < 1) {
870 ro_all = 1;
871 }
872 if (rw_all < 1) {
873 rw_all = 1;
874 }
875
876 int all_ro_count = 0;
877 int all_ro_bytes = 0;
878 int all_rw_count = 0;
879 int all_rw_bytes = 0;
880
881 // To make fmt_stats be a syntactic constant (for format warnings), use #define.
882 #define fmt_stats "%-20s: %8d %10d %5.1f | %8d %10d %5.1f | %8d %10d %5.1f"
883 const char *sep = "--------------------+---------------------------+---------------------------+--------------------------";
884 const char *hdr = " ro_cnt ro_bytes % | rw_cnt rw_bytes % | all_cnt all_bytes %";
885
886 ResourceMark rm;
887 LogMessage(cds) msg;
888 stringStream info_stream;
889
890 info_stream.print_cr("Detailed metadata info (excluding od/st regions; rw stats include md/mc regions):");
891 info_stream.print_cr("%s", hdr);
892 info_stream.print_cr("%s", sep);
893 for (int type = 0; type < int(_number_of_types); type ++) {
894 const char *name = type_name((Type)type);
895 int ro_count = _counts[RO][type];
896 int ro_bytes = _bytes [RO][type];
897 int rw_count = _counts[RW][type];
898 int rw_bytes = _bytes [RW][type];
899 int count = ro_count + rw_count;
900 int bytes = ro_bytes + rw_bytes;
901
902 double ro_perc = percent_of(ro_bytes, ro_all);
903 double rw_perc = percent_of(rw_bytes, rw_all);
904 double perc = percent_of(bytes, ro_all + rw_all);
905
906 info_stream.print_cr(fmt_stats, name,
907 ro_count, ro_bytes, ro_perc,
908 rw_count, rw_bytes, rw_perc,
909 count, bytes, perc);
910
911 all_ro_count += ro_count;
912 all_ro_bytes += ro_bytes;
913 all_rw_count += rw_count;
914 all_rw_bytes += rw_bytes;
915 }
916
917 int all_count = all_ro_count + all_rw_count;
918 int all_bytes = all_ro_bytes + all_rw_bytes;
919
920 double all_ro_perc = percent_of(all_ro_bytes, ro_all);
921 double all_rw_perc = percent_of(all_rw_bytes, rw_all);
922 double all_perc = percent_of(all_bytes, ro_all + rw_all);
923
924 info_stream.print_cr("%s", sep);
925 info_stream.print_cr(fmt_stats, "Total",
926 all_ro_count, all_ro_bytes, all_ro_perc,
927 all_rw_count, all_rw_bytes, all_rw_perc,
928 all_count, all_bytes, all_perc);
929
930 assert(all_ro_bytes == ro_all, "everything should have been counted");
931 assert(all_rw_bytes == rw_all, "everything should have been counted");
932
933 msg.info("%s", info_stream.as_string());
934 #undef fmt_stats
935 }
936
937 // Populate the shared space.
938
939 class VM_PopulateDumpSharedSpace: public VM_Operation {
940 private:
941 GrowableArray<MemRegion> *_string_regions;
942 GrowableArray<MemRegion> *_open_archive_heap_regions;
943
944 void dump_java_heap_objects() NOT_CDS_JAVA_HEAP_RETURN;
945 void dump_symbols();
946 char* dump_read_only_tables();
947 void print_region_stats();
948 void print_heap_region_stats(GrowableArray<MemRegion> *heap_mem,
949 const char *name, const size_t total_size);
950 public:
951
952 VMOp_Type type() const { return VMOp_PopulateDumpSharedSpace; }
953 void doit(); // outline because gdb sucks
954 static void write_region(FileMapInfo* mapinfo, int region, DumpRegion* space, bool read_only, bool allow_exec);
955 }; // class VM_PopulateDumpSharedSpace
956
957 class SortedSymbolClosure: public SymbolClosure {
958 GrowableArray<Symbol*> _symbols;
959 virtual void do_symbol(Symbol** sym) {
960 assert((*sym)->is_permanent(), "archived symbols must be permanent");
961 _symbols.append(*sym);
962 }
963 static int compare_symbols_by_address(Symbol** a, Symbol** b) {
964 if (a[0] < b[0]) {
965 return -1;
966 } else if (a[0] == b[0]) {
967 return 0;
968 } else {
969 return 1;
970 }
971 }
972
973 public:
974 SortedSymbolClosure() {
975 SymbolTable::symbols_do(this);
976 _symbols.sort(compare_symbols_by_address);
977 }
978 GrowableArray<Symbol*>* get_sorted_symbols() {
979 return &_symbols;
980 }
981 };
982
983 // ArchiveCompactor --
984 //
985 // This class is the central piece of shared archive compaction -- all metaspace data are
986 // initially allocated outside of the shared regions. ArchiveCompactor copies the
987 // metaspace data into their final location in the shared regions.
988
989 class ArchiveCompactor : AllStatic {
990 static DumpAllocStats* _alloc_stats;
991 static SortedSymbolClosure* _ssc;
992
993 static unsigned my_hash(const address& a) {
994 return primitive_hash<address>(a);
995 }
996 static bool my_equals(const address& a0, const address& a1) {
997 return primitive_equals<address>(a0, a1);
998 }
999 typedef ResourceHashtable<
1000 address, address,
1001 ArchiveCompactor::my_hash, // solaris compiler doesn't like: primitive_hash<address>
1002 ArchiveCompactor::my_equals, // solaris compiler doesn't like: primitive_equals<address>
1003 16384, ResourceObj::C_HEAP> RelocationTable;
1004 static RelocationTable* _new_loc_table;
1005
1006 public:
1007 static void initialize() {
1008 _alloc_stats = new(ResourceObj::C_HEAP, mtInternal)DumpAllocStats;
1009 _new_loc_table = new(ResourceObj::C_HEAP, mtInternal)RelocationTable;
1010 }
1011 static DumpAllocStats* alloc_stats() {
1012 return _alloc_stats;
1013 }
1014
1015 static void allocate(MetaspaceClosure::Ref* ref, bool read_only) {
1016 address obj = ref->obj();
1017 int bytes = ref->size() * BytesPerWord;
1018 char* p;
1019 size_t alignment = BytesPerWord;
1020 char* oldtop;
1021 char* newtop;
1022
1023 if (read_only) {
1024 oldtop = _ro_region.top();
1025 p = _ro_region.allocate(bytes, alignment);
1026 newtop = _ro_region.top();
1027 } else {
1028 oldtop = _rw_region.top();
1029 p = _rw_region.allocate(bytes, alignment);
1030 newtop = _rw_region.top();
1031 }
1032 memcpy(p, obj, bytes);
1033 bool isnew = _new_loc_table->put(obj, (address)p);
1034 log_trace(cds)("Copy: " PTR_FORMAT " ==> " PTR_FORMAT " %d", p2i(obj), p2i(p), bytes);
1035 assert(isnew, "must be");
1036
1037 _alloc_stats->record(ref->msotype(), int(newtop - oldtop), read_only);
1038 if (ref->msotype() == MetaspaceObj::SymbolType) {
1039 uintx delta = MetaspaceShared::object_delta(p);
1040 if (delta > MAX_SHARED_DELTA) {
1041 // This is just a sanity check and should not appear in any real world usage. This
1042 // happens only if you allocate more than 2GB of Symbols and would require
1043 // millions of shared classes.
1044 vm_exit_during_initialization("Too many Symbols in the CDS archive",
1045 "Please reduce the number of shared classes.");
1046 }
1047 }
1048 }
1049
1050 static address get_new_loc(MetaspaceClosure::Ref* ref) {
1051 address* pp = _new_loc_table->get(ref->obj());
1052 assert(pp != NULL, "must be");
1053 return *pp;
1054 }
1055
1056 private:
1057 // Makes a shallow copy of visited MetaspaceObj's
1058 class ShallowCopier: public UniqueMetaspaceClosure {
1059 bool _read_only;
1060 public:
1061 ShallowCopier(bool read_only) : _read_only(read_only) {}
1062
1063 virtual void do_unique_ref(Ref* ref, bool read_only) {
1064 if (read_only == _read_only) {
1065 allocate(ref, read_only);
1066 }
1067 }
1068 };
1069
1070 // Relocate embedded pointers within a MetaspaceObj's shallow copy
1071 class ShallowCopyEmbeddedRefRelocator: public UniqueMetaspaceClosure {
1072 public:
1073 virtual void do_unique_ref(Ref* ref, bool read_only) {
1074 address new_loc = get_new_loc(ref);
1075 RefRelocator refer;
1076 ref->metaspace_pointers_do_at(&refer, new_loc);
1077 }
1078 };
1079
1080 // Relocate a reference to point to its shallow copy
1081 class RefRelocator: public MetaspaceClosure {
1082 public:
1083 virtual bool do_ref(Ref* ref, bool read_only) {
1084 if (ref->not_null()) {
1085 ref->update(get_new_loc(ref));
1086 }
1087 return false; // Do not recurse.
1088 }
1089 };
1090
1091 #ifdef ASSERT
1092 class IsRefInArchiveChecker: public MetaspaceClosure {
1093 public:
1094 virtual bool do_ref(Ref* ref, bool read_only) {
1095 if (ref->not_null()) {
1096 char* obj = (char*)ref->obj();
1097 assert(_ro_region.contains(obj) || _rw_region.contains(obj),
1098 "must be relocated to point to CDS archive");
1099 }
1100 return false; // Do not recurse.
1101 }
1102 };
1103 #endif
1104
1105 public:
1106 static void copy_and_compact() {
1107 // We should no longer allocate anything from the metaspace, so that
1108 // we can have a stable set of MetaspaceObjs to work with.
1109 Metaspace::freeze();
1110
1111 ResourceMark rm;
1112 SortedSymbolClosure the_ssc; // StackObj
1113 _ssc = &the_ssc;
1114
1115 tty->print_cr("Scanning all metaspace objects ... ");
1116 {
1117 // allocate and shallow-copy RW objects, immediately following the MC region
1118 tty->print_cr("Allocating RW objects ... ");
1119 _mc_region.pack(&_rw_region);
1120
1121 ResourceMark rm;
1122 ShallowCopier rw_copier(false);
1123 iterate_roots(&rw_copier);
1124 }
1125 {
1126 // allocate and shallow-copy of RO object, immediately following the RW region
1127 tty->print_cr("Allocating RO objects ... ");
1128 _rw_region.pack(&_ro_region);
1129
1130 ResourceMark rm;
1131 ShallowCopier ro_copier(true);
1132 iterate_roots(&ro_copier);
1133 }
1134 {
1135 tty->print_cr("Relocating embedded pointers ... ");
1136 ResourceMark rm;
1137 ShallowCopyEmbeddedRefRelocator emb_reloc;
1138 iterate_roots(&emb_reloc);
1139 }
1140 {
1141 tty->print_cr("Relocating external roots ... ");
1142 ResourceMark rm;
1143 RefRelocator ext_reloc;
1144 iterate_roots(&ext_reloc);
1145 }
1146
1147 #ifdef ASSERT
1148 {
1149 tty->print_cr("Verifying external roots ... ");
1150 ResourceMark rm;
1151 IsRefInArchiveChecker checker;
1152 iterate_roots(&checker);
1153 }
1154 #endif
1155
1156
1157 // cleanup
1158 _ssc = NULL;
1159 }
1160
1161 // We must relocate the System::_well_known_klasses only after we have copied the
1162 // java objects in during dump_java_heap_objects(): during the object copy, we operate on
1163 // old objects which assert that their klass is the original klass.
1164 static void relocate_well_known_klasses() {
1165 {
1166 tty->print_cr("Relocating SystemDictionary::_well_known_klasses[] ... ");
1167 ResourceMark rm;
1168 RefRelocator ext_reloc;
1169 SystemDictionary::well_known_klasses_do(&ext_reloc);
1170 }
1171 // NOTE: after this point, we shouldn't have any globals that can reach the old
1172 // objects.
1173
1174 // We cannot use any of the objects in the heap anymore (except for the objects
1175 // in the CDS shared string regions) because their headers no longer point to
1176 // valid Klasses.
1177 }
1178
1179 static void iterate_roots(MetaspaceClosure* it) {
1180 GrowableArray<Symbol*>* symbols = _ssc->get_sorted_symbols();
1181 for (int i=0; i<symbols->length(); i++) {
1182 it->push(symbols->adr_at(i));
1183 }
1184 if (_global_klass_objects != NULL) {
1185 // Need to fix up the pointers
1186 for (int i = 0; i < _global_klass_objects->length(); i++) {
1187 // NOTE -- this requires that the vtable is NOT yet patched, or else we are hosed.
1188 it->push(_global_klass_objects->adr_at(i));
1189 }
1190 }
1191 FileMapInfo::metaspace_pointers_do(it);
1192 SystemDictionary::classes_do(it);
1193 Universe::metaspace_pointers_do(it);
1194 SymbolTable::metaspace_pointers_do(it);
1195 vmSymbols::metaspace_pointers_do(it);
1196 }
1197
1198 static Klass* get_relocated_klass(Klass* orig_klass) {
1199 address* pp = _new_loc_table->get((address)orig_klass);
1200 assert(pp != NULL, "must be");
1201 Klass* klass = (Klass*)(*pp);
1202 assert(klass->is_klass(), "must be");
1203 return klass;
1204 }
1205 };
1206
1207 DumpAllocStats* ArchiveCompactor::_alloc_stats;
1208 SortedSymbolClosure* ArchiveCompactor::_ssc;
1209 ArchiveCompactor::RelocationTable* ArchiveCompactor::_new_loc_table;
1210
1211 void VM_PopulateDumpSharedSpace::write_region(FileMapInfo* mapinfo, int region_idx,
1212 DumpRegion* dump_region, bool read_only, bool allow_exec) {
1213 mapinfo->write_region(region_idx, dump_region->base(), dump_region->used(), read_only, allow_exec);
1214 }
1215
1216 void VM_PopulateDumpSharedSpace::dump_symbols() {
1217 tty->print_cr("Dumping symbol table ...");
1218
1219 NOT_PRODUCT(SymbolTable::verify());
1220 SymbolTable::write_to_archive();
1221 }
1222
1223 char* VM_PopulateDumpSharedSpace::dump_read_only_tables() {
1224 char* oldtop = _ro_region.top();
1225 // Reorder the system dictionary. Moving the symbols affects
1226 // how the hash table indices are calculated.
1227 SystemDictionary::reorder_dictionary_for_sharing();
1228 tty->print("Removing java_mirror ... ");
1229 remove_java_mirror_in_classes();
1230 tty->print_cr("done. ");
1231 NOT_PRODUCT(SystemDictionary::verify();)
1232
1233 size_t buckets_bytes = SystemDictionary::count_bytes_for_buckets();
1234 char* buckets_top = _ro_region.allocate(buckets_bytes, sizeof(intptr_t));
1235 SystemDictionary::copy_buckets(buckets_top, _ro_region.top());
1236
1237 size_t table_bytes = SystemDictionary::count_bytes_for_table();
1238 char* table_top = _ro_region.allocate(table_bytes, sizeof(intptr_t));
1239 SystemDictionary::copy_table(table_top, _ro_region.top());
1240
1241 // Write the other data to the output array.
1242 WriteClosure wc(&_ro_region);
1243 MetaspaceShared::serialize(&wc);
1244
1245 char* newtop = _ro_region.top();
1246 ArchiveCompactor::alloc_stats()->record_other_type(int(newtop - oldtop), true);
1247 return buckets_top;
1248 }
1249
1250 void VM_PopulateDumpSharedSpace::doit() {
1251 Thread* THREAD = VMThread::vm_thread();
1252
1253 NOT_PRODUCT(SystemDictionary::verify();)
1254 // The following guarantee is meant to ensure that no loader constraints
1255 // exist yet, since the constraints table is not shared. This becomes
1256 // more important now that we don't re-initialize vtables/itables for
1257 // shared classes at runtime, where constraints were previously created.
1258 guarantee(SystemDictionary::constraints()->number_of_entries() == 0,
1259 "loader constraints are not saved");
1260 guarantee(SystemDictionary::placeholders()->number_of_entries() == 0,
1261 "placeholders are not saved");
1262 // Revisit and implement this if we prelink method handle call sites:
1263 guarantee(SystemDictionary::invoke_method_table() == NULL ||
1264 SystemDictionary::invoke_method_table()->number_of_entries() == 0,
1265 "invoke method table is not saved");
1266
1267 // At this point, many classes have been loaded.
1268 // Gather systemDictionary classes in a global array and do everything to
1269 // that so we don't have to walk the SystemDictionary again.
1270 _global_klass_objects = new GrowableArray<Klass*>(1000);
1271 CollectClassesClosure collect_classes;
1272 ClassLoaderDataGraph::loaded_classes_do(&collect_classes);
1273
1274 tty->print_cr("Number of classes %d", _global_klass_objects->length());
1275 {
1276 int num_type_array = 0, num_obj_array = 0, num_inst = 0;
1277 for (int i = 0; i < _global_klass_objects->length(); i++) {
1278 Klass* k = _global_klass_objects->at(i);
1279 if (k->is_instance_klass()) {
1280 num_inst ++;
1281 } else if (k->is_objArray_klass()) {
1282 num_obj_array ++;
1283 } else {
1284 assert(k->is_typeArray_klass(), "sanity");
1285 num_type_array ++;
1286 }
1287 }
1288 tty->print_cr(" instance classes = %5d", num_inst);
1289 tty->print_cr(" obj array classes = %5d", num_obj_array);
1290 tty->print_cr(" type array classes = %5d", num_type_array);
1291 }
1292
1293 // Ensure the ConstMethods won't be modified at run-time
1294 tty->print("Updating ConstMethods ... ");
1295 rewrite_nofast_bytecodes_and_calculate_fingerprints();
1296 tty->print_cr("done. ");
1297
1298 // Move classes from platform/system dictionaries into the boot dictionary
1299 SystemDictionary::combine_shared_dictionaries();
1300
1301 // Remove all references outside the metadata
1302 tty->print("Removing unshareable information ... ");
1303 remove_unshareable_in_classes();
1304 tty->print_cr("done. ");
1305
1306 // We don't support archiving anonymous classes. Verify that they are not stored in
1307 // the any dictionaries.
1308 NOT_PRODUCT(assert_no_anonymoys_classes_in_dictionaries());
1309
1310 SystemDictionaryShared::finalize_verification_constraints();
1311
1312 ArchiveCompactor::initialize();
1313 ArchiveCompactor::copy_and_compact();
1314
1315 dump_symbols();
1316
1317 // Dump supported java heap objects
1318 _string_regions = NULL;
1319 _open_archive_heap_regions = NULL;
1320 dump_java_heap_objects();
1321
1322 ArchiveCompactor::relocate_well_known_klasses();
1323
1324 char* read_only_tables_start = dump_read_only_tables();
1325 _ro_region.pack(&_md_region);
1326
1327 char* vtbl_list = _md_region.top();
1328 MetaspaceShared::allocate_cpp_vtable_clones();
1329 _md_region.pack(&_od_region);
1330
1331 // Relocate the archived class file data into the od region
1332 relocate_cached_class_file();
1333 _od_region.pack();
1334
1335 // The 5 core spaces are allocated consecutively mc->rw->ro->md->od, so there total size
1336 // is just the spaces between the two ends.
1337 size_t core_spaces_size = _od_region.end() - _mc_region.base();
1338 assert(core_spaces_size == (size_t)align_up(core_spaces_size, Metaspace::reserve_alignment()),
1339 "should already be aligned");
1340
1341 // During patching, some virtual methods may be called, so at this point
1342 // the vtables must contain valid methods (as filled in by CppVtableCloner::allocate).
1343 MetaspaceShared::patch_cpp_vtable_pointers();
1344
1345 // The vtable clones contain addresses of the current process.
1346 // We don't want to write these addresses into the archive.
1347 MetaspaceShared::zero_cpp_vtable_clones_for_writing();
1348
1349 // Create and write the archive file that maps the shared spaces.
1350
1351 FileMapInfo* mapinfo = new FileMapInfo();
1352 mapinfo->populate_header(os::vm_allocation_granularity());
1353 mapinfo->set_read_only_tables_start(read_only_tables_start);
1354 mapinfo->set_misc_data_patching_start(vtbl_list);
1355 mapinfo->set_cds_i2i_entry_code_buffers(MetaspaceShared::cds_i2i_entry_code_buffers());
1356 mapinfo->set_cds_i2i_entry_code_buffers_size(MetaspaceShared::cds_i2i_entry_code_buffers_size());
1357 mapinfo->set_core_spaces_size(core_spaces_size);
1358
1359 for (int pass=1; pass<=2; pass++) {
1360 if (pass == 1) {
1361 // The first pass doesn't actually write the data to disk. All it
1362 // does is to update the fields in the mapinfo->_header.
1363 } else {
1364 // After the first pass, the contents of mapinfo->_header are finalized,
1365 // so we can compute the header's CRC, and write the contents of the header
1366 // and the regions into disk.
1367 mapinfo->open_for_write();
1368 mapinfo->set_header_crc(mapinfo->compute_header_crc());
1369 }
1370 mapinfo->write_header();
1371
1372 // NOTE: md contains the trampoline code for method entries, which are patched at run time,
1373 // so it needs to be read/write.
1374 write_region(mapinfo, MetaspaceShared::mc, &_mc_region, /*read_only=*/false,/*allow_exec=*/true);
1375 write_region(mapinfo, MetaspaceShared::rw, &_rw_region, /*read_only=*/false,/*allow_exec=*/false);
1376 write_region(mapinfo, MetaspaceShared::ro, &_ro_region, /*read_only=*/true, /*allow_exec=*/false);
1377 write_region(mapinfo, MetaspaceShared::md, &_md_region, /*read_only=*/false,/*allow_exec=*/false);
1378 write_region(mapinfo, MetaspaceShared::od, &_od_region, /*read_only=*/true, /*allow_exec=*/false);
1379
1380 _total_string_region_size = mapinfo->write_archive_heap_regions(
1381 _string_regions,
1382 MetaspaceShared::first_string,
1383 MetaspaceShared::max_strings);
1384 _total_open_archive_region_size = mapinfo->write_archive_heap_regions(
1385 _open_archive_heap_regions,
1386 MetaspaceShared::first_open_archive_heap_region,
1387 MetaspaceShared::max_open_archive_heap_region);
1388 }
1389
1390 mapinfo->close();
1391
1392 // Restore the vtable in case we invoke any virtual methods.
1393 MetaspaceShared::clone_cpp_vtables((intptr_t*)vtbl_list);
1394
1395 print_region_stats();
1396
1397 if (log_is_enabled(Info, cds)) {
1398 ArchiveCompactor::alloc_stats()->print_stats(int(_ro_region.used()), int(_rw_region.used()),
1399 int(_mc_region.used()), int(_md_region.used()));
1400 }
1401
1402 if (PrintSystemDictionaryAtExit) {
1403 SystemDictionary::print();
1404 }
1405 // There may be other pending VM operations that operate on the InstanceKlasses,
1406 // which will fail because InstanceKlasses::remove_unshareable_info()
1407 // has been called. Forget these operations and exit the VM directly.
1408 vm_direct_exit(0);
1409 }
1410
1411 void VM_PopulateDumpSharedSpace::print_region_stats() {
1412 // Print statistics of all the regions
1413 const size_t total_reserved = _ro_region.reserved() + _rw_region.reserved() +
1414 _mc_region.reserved() + _md_region.reserved() +
1415 _od_region.reserved() +
1416 _total_string_region_size +
1417 _total_open_archive_region_size;
1418 const size_t total_bytes = _ro_region.used() + _rw_region.used() +
1419 _mc_region.used() + _md_region.used() +
1420 _od_region.used() +
1421 _total_string_region_size +
1422 _total_open_archive_region_size;
1423 const double total_u_perc = percent_of(total_bytes, total_reserved);
1424
1425 _mc_region.print(total_reserved);
1426 _rw_region.print(total_reserved);
1427 _ro_region.print(total_reserved);
1428 _md_region.print(total_reserved);
1429 _od_region.print(total_reserved);
1430 print_heap_region_stats(_string_regions, "st", total_reserved);
1431 print_heap_region_stats(_open_archive_heap_regions, "oa", total_reserved);
1432
1433 tty->print_cr("total : " SIZE_FORMAT_W(9) " [100.0%% of total] out of " SIZE_FORMAT_W(9) " bytes [%5.1f%% used]",
1434 total_bytes, total_reserved, total_u_perc);
1435 }
1436
1437 void VM_PopulateDumpSharedSpace::print_heap_region_stats(GrowableArray<MemRegion> *heap_mem,
1438 const char *name, const size_t total_size) {
1439 int arr_len = heap_mem == NULL ? 0 : heap_mem->length();
1440 for (int i = 0; i < arr_len; i++) {
1441 char* start = (char*)heap_mem->at(i).start();
1442 size_t size = heap_mem->at(i).byte_size();
1443 char* top = start + size;
1444 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,
1445 name, i, size, size/double(total_size)*100.0, size, p2i(start));
1446
1447 }
1448 }
1449
1450 // Update a Java object to point its Klass* to the new location after
1451 // shared archive has been compacted.
1452 void MetaspaceShared::relocate_klass_ptr(oop o) {
1453 assert(DumpSharedSpaces, "sanity");
1454 Klass* k = ArchiveCompactor::get_relocated_klass(o->klass());
1455 o->set_klass(k);
1456 }
1457
1458 class LinkSharedClassesClosure : public KlassClosure {
1459 Thread* THREAD;
1460 bool _made_progress;
1461 public:
1462 LinkSharedClassesClosure(Thread* thread) : THREAD(thread), _made_progress(false) {}
1463
1464 void reset() { _made_progress = false; }
1465 bool made_progress() const { return _made_progress; }
1466
1467 void do_klass(Klass* k) {
1468 if (k->is_instance_klass()) {
1469 InstanceKlass* ik = InstanceKlass::cast(k);
1470 // Link the class to cause the bytecodes to be rewritten and the
1471 // cpcache to be created. Class verification is done according
1472 // to -Xverify setting.
1473 _made_progress |= MetaspaceShared::try_link_class(ik, THREAD);
1474 guarantee(!HAS_PENDING_EXCEPTION, "exception in link_class");
1475
1476 ik->constants()->resolve_class_constants(THREAD);
1477 }
1478 }
1479 };
1480
1481 class CheckSharedClassesClosure : public KlassClosure {
1482 bool _made_progress;
1483 public:
1484 CheckSharedClassesClosure() : _made_progress(false) {}
1485
1486 void reset() { _made_progress = false; }
1487 bool made_progress() const { return _made_progress; }
1488 void do_klass(Klass* k) {
1489 if (k->is_instance_klass() && InstanceKlass::cast(k)->check_sharing_error_state()) {
1490 _made_progress = true;
1491 }
1492 }
1493 };
1494
1495 void MetaspaceShared::check_shared_class_loader_type(Klass* k) {
1496 if (k->is_instance_klass()) {
1497 InstanceKlass* ik = InstanceKlass::cast(k);
1498 u2 loader_type = ik->loader_type();
1499 ResourceMark rm;
1500 guarantee(loader_type != 0,
1501 "Class loader type is not set for this class %s", ik->name()->as_C_string());
1502 }
1503 }
1504
1505 void MetaspaceShared::link_and_cleanup_shared_classes(TRAPS) {
1506 // We need to iterate because verification may cause additional classes
1507 // to be loaded.
1508 LinkSharedClassesClosure link_closure(THREAD);
1509 do {
1510 link_closure.reset();
1511 ClassLoaderDataGraph::loaded_classes_do(&link_closure);
1512 guarantee(!HAS_PENDING_EXCEPTION, "exception in link_class");
1513 } while (link_closure.made_progress());
1514
1515 if (_has_error_classes) {
1516 // Mark all classes whose super class or interfaces failed verification.
1517 CheckSharedClassesClosure check_closure;
1518 do {
1519 // Not completely sure if we need to do this iteratively. Anyway,
1520 // we should come here only if there are unverifiable classes, which
1521 // shouldn't happen in normal cases. So better safe than sorry.
1522 check_closure.reset();
1523 ClassLoaderDataGraph::loaded_classes_do(&check_closure);
1524 } while (check_closure.made_progress());
1525
1526 if (IgnoreUnverifiableClassesDuringDump) {
1527 // This is useful when running JCK or SQE tests. You should not
1528 // enable this when running real apps.
1529 SystemDictionary::remove_classes_in_error_state();
1530 } else {
1531 tty->print_cr("Please remove the unverifiable classes from your class list and try again");
1532 exit(1);
1533 }
1534 }
1535 }
1536
1537 void MetaspaceShared::prepare_for_dumping() {
1538 Arguments::check_unsupported_dumping_properties();
1539 ClassLoader::initialize_shared_path();
1540 FileMapInfo::allocate_classpath_entry_table();
1541 }
1542
1543 // Preload classes from a list, populate the shared spaces and dump to a
1544 // file.
1545 void MetaspaceShared::preload_and_dump(TRAPS) {
1546 { TraceTime timer("Dump Shared Spaces", TRACETIME_LOG(Info, startuptime));
1547 ResourceMark rm;
1548 char class_list_path_str[JVM_MAXPATHLEN];
1549 // Preload classes to be shared.
1550 // Should use some os:: method rather than fopen() here. aB.
1551 const char* class_list_path;
1552 if (SharedClassListFile == NULL) {
1553 // Construct the path to the class list (in jre/lib)
1554 // Walk up two directories from the location of the VM and
1555 // optionally tack on "lib" (depending on platform)
1556 os::jvm_path(class_list_path_str, sizeof(class_list_path_str));
1557 for (int i = 0; i < 3; i++) {
1558 char *end = strrchr(class_list_path_str, *os::file_separator());
1559 if (end != NULL) *end = '\0';
1560 }
1561 int class_list_path_len = (int)strlen(class_list_path_str);
1562 if (class_list_path_len >= 3) {
1563 if (strcmp(class_list_path_str + class_list_path_len - 3, "lib") != 0) {
1564 if (class_list_path_len < JVM_MAXPATHLEN - 4) {
1565 jio_snprintf(class_list_path_str + class_list_path_len,
1566 sizeof(class_list_path_str) - class_list_path_len,
1567 "%slib", os::file_separator());
1568 class_list_path_len += 4;
1569 }
1570 }
1571 }
1572 if (class_list_path_len < JVM_MAXPATHLEN - 10) {
1573 jio_snprintf(class_list_path_str + class_list_path_len,
1574 sizeof(class_list_path_str) - class_list_path_len,
1575 "%sclasslist", os::file_separator());
1576 }
1577 class_list_path = class_list_path_str;
1578 } else {
1579 class_list_path = SharedClassListFile;
1580 }
1581
1582 tty->print_cr("Loading classes to share ...");
1583 _has_error_classes = false;
1584 int class_count = preload_classes(class_list_path, THREAD);
1585 if (ExtraSharedClassListFile) {
1586 class_count += preload_classes(ExtraSharedClassListFile, THREAD);
1587 }
1588 tty->print_cr("Loading classes to share: done.");
1589
1590 log_info(cds)("Shared spaces: preloaded %d classes", class_count);
1591
1592 // Rewrite and link classes
1593 tty->print_cr("Rewriting and linking classes ...");
1594
1595 // Link any classes which got missed. This would happen if we have loaded classes that
1596 // were not explicitly specified in the classlist. E.g., if an interface implemented by class K
1597 // fails verification, all other interfaces that were not specified in the classlist but
1598 // are implemented by K are not verified.
1599 link_and_cleanup_shared_classes(CATCH);
1600 tty->print_cr("Rewriting and linking classes: done");
1601
1602 SystemDictionary::clear_invoke_method_table();
1603
1604 VM_PopulateDumpSharedSpace op;
1605 VMThread::execute(&op);
1606 }
1607 }
1608
1609
1610 int MetaspaceShared::preload_classes(const char* class_list_path, TRAPS) {
1611 ClassListParser parser(class_list_path);
1612 int class_count = 0;
1613
1614 while (parser.parse_one_line()) {
1615 Klass* klass = ClassLoaderExt::load_one_class(&parser, THREAD);
1616 if (HAS_PENDING_EXCEPTION) {
1617 if (klass == NULL &&
1618 (PENDING_EXCEPTION->klass()->name() == vmSymbols::java_lang_ClassNotFoundException())) {
1619 // print a warning only when the pending exception is class not found
1620 tty->print_cr("Preload Warning: Cannot find %s", parser.current_class_name());
1621 }
1622 CLEAR_PENDING_EXCEPTION;
1623 }
1624 if (klass != NULL) {
1625 if (log_is_enabled(Trace, cds)) {
1626 ResourceMark rm;
1627 log_trace(cds)("Shared spaces preloaded: %s", klass->external_name());
1628 }
1629
1630 if (klass->is_instance_klass()) {
1631 InstanceKlass* ik = InstanceKlass::cast(klass);
1632
1633 // Link the class to cause the bytecodes to be rewritten and the
1634 // cpcache to be created. The linking is done as soon as classes
1635 // are loaded in order that the related data structures (klass and
1636 // cpCache) are located together.
1637 try_link_class(ik, THREAD);
1638 guarantee(!HAS_PENDING_EXCEPTION, "exception in link_class");
1639 }
1640
1641 class_count++;
1642 }
1643 }
1644
1645 return class_count;
1646 }
1647
1648 // Returns true if the class's status has changed
1649 bool MetaspaceShared::try_link_class(InstanceKlass* ik, TRAPS) {
1650 assert(DumpSharedSpaces, "should only be called during dumping");
1651 if (ik->init_state() < InstanceKlass::linked) {
1652 bool saved = BytecodeVerificationLocal;
1653 if (!(ik->is_shared_boot_class())) {
1654 // The verification decision is based on BytecodeVerificationRemote
1655 // for non-system classes. Since we are using the NULL classloader
1656 // to load non-system classes during dumping, we need to temporarily
1657 // change BytecodeVerificationLocal to be the same as
1658 // BytecodeVerificationRemote. Note this can cause the parent system
1659 // classes also being verified. The extra overhead is acceptable during
1660 // dumping.
1661 BytecodeVerificationLocal = BytecodeVerificationRemote;
1662 }
1663 ik->link_class(THREAD);
1664 if (HAS_PENDING_EXCEPTION) {
1665 ResourceMark rm;
1666 tty->print_cr("Preload Warning: Verification failed for %s",
1667 ik->external_name());
1668 CLEAR_PENDING_EXCEPTION;
1669 ik->set_in_error_state();
1670 _has_error_classes = true;
1671 }
1672 BytecodeVerificationLocal = saved;
1673 return true;
1674 } else {
1675 return false;
1676 }
1677 }
1678
1679 #if INCLUDE_CDS_JAVA_HEAP
1680 void VM_PopulateDumpSharedSpace::dump_java_heap_objects() {
1681 if (!MetaspaceShared::is_heap_object_archiving_allowed()) {
1682 if (log_is_enabled(Info, cds)) {
1683 log_info(cds)(
1684 "Archived java heap is not supported as UseG1GC, "
1685 "UseCompressedOops and UseCompressedClassPointers are required."
1686 "Current settings: UseG1GC=%s, UseCompressedOops=%s, UseCompressedClassPointers=%s.",
1687 BOOL_TO_STR(UseG1GC), BOOL_TO_STR(UseCompressedOops),
1688 BOOL_TO_STR(UseCompressedClassPointers));
1689 }
1690 return;
1691 }
1692
1693 {
1694 NoSafepointVerifier nsv;
1695
1696 // Cache for recording where the archived objects are copied to
1697 MetaspaceShared::create_archive_object_cache();
1698
1699 tty->print_cr("Dumping String objects to closed archive heap region ...");
1700 NOT_PRODUCT(StringTable::verify());
1701 // The string space has maximum two regions. See FileMapInfo::write_archive_heap_regions() for details.
1702 _string_regions = new GrowableArray<MemRegion>(2);
1703 StringTable::write_to_archive(_string_regions);
1704
1705 tty->print_cr("Dumping objects to open archive heap region ...");
1706 _open_archive_heap_regions = new GrowableArray<MemRegion>(2);
1707 MetaspaceShared::dump_open_archive_heap_objects(_open_archive_heap_regions);
1708
1709 MetaspaceShared::destroy_archive_object_cache();
1710 }
1711
1712 G1HeapVerifier::verify_archive_regions();
1713 }
1714
1715 void MetaspaceShared::dump_open_archive_heap_objects(
1716 GrowableArray<MemRegion> * open_archive) {
1717 assert(UseG1GC, "Only support G1 GC");
1718 assert(UseCompressedOops && UseCompressedClassPointers,
1719 "Only support UseCompressedOops and UseCompressedClassPointers enabled");
1720
1721 Thread* THREAD = Thread::current();
1722 G1CollectedHeap::heap()->begin_archive_alloc_range(true /* open */);
1723
1724 MetaspaceShared::archive_resolved_constants(THREAD);
1725
1726 G1CollectedHeap::heap()->end_archive_alloc_range(open_archive,
1727 os::vm_allocation_granularity());
1728 }
1729
1730 MetaspaceShared::ArchivedObjectCache* MetaspaceShared::_archive_object_cache = NULL;
1731 oop MetaspaceShared::archive_heap_object(oop obj, Thread* THREAD) {
1732 assert(DumpSharedSpaces, "dump-time only");
1733
1734 ArchivedObjectCache* cache = MetaspaceShared::archive_object_cache();
1735 oop* p = cache->get(obj);
1736 if (p != NULL) {
1737 // already archived
1738 return *p;
1739 }
1740
1741 int len = obj->size();
1742 if (G1CollectedHeap::heap()->is_archive_alloc_too_large(len)) {
1743 return NULL;
1744 }
1745
1746 int hash = obj->identity_hash();
1747 oop archived_oop = (oop)G1CollectedHeap::heap()->archive_mem_allocate(len);
1748 if (archived_oop != NULL) {
1749 Copy::aligned_disjoint_words((HeapWord*)obj, (HeapWord*)archived_oop, len);
1750 relocate_klass_ptr(archived_oop);
1751 cache->put(obj, archived_oop);
1752 }
1753 return archived_oop;
1754 }
1755
1756 void MetaspaceShared::archive_resolved_constants(Thread* THREAD) {
1757 int i;
1758 for (i = 0; i < _global_klass_objects->length(); i++) {
1759 Klass* k = _global_klass_objects->at(i);
1760 if (k->is_instance_klass()) {
1761 InstanceKlass* ik = InstanceKlass::cast(k);
1762 ik->constants()->archive_resolved_references(THREAD);
1763 }
1764 }
1765 }
1766
1767 void MetaspaceShared::fixup_mapped_heap_regions() {
1768 FileMapInfo *mapinfo = FileMapInfo::current_info();
1769 mapinfo->fixup_mapped_heap_regions();
1770 }
1771 #endif // INCLUDE_CDS_JAVA_HEAP
1772
1773 // Closure for serializing initialization data in from a data area
1774 // (ptr_array) read from the shared file.
1775
1776 class ReadClosure : public SerializeClosure {
1777 private:
1778 intptr_t** _ptr_array;
1779
1780 inline intptr_t nextPtr() {
1781 return *(*_ptr_array)++;
1782 }
1783
1784 public:
1785 ReadClosure(intptr_t** ptr_array) { _ptr_array = ptr_array; }
1786
1787 void do_ptr(void** p) {
1788 assert(*p == NULL, "initializing previous initialized pointer.");
1789 intptr_t obj = nextPtr();
1790 assert((intptr_t)obj >= 0 || (intptr_t)obj < -100,
1791 "hit tag while initializing ptrs.");
1792 *p = (void*)obj;
1793 }
1794
1795 void do_u4(u4* p) {
1796 intptr_t obj = nextPtr();
1797 *p = (u4)(uintx(obj));
1798 }
1799
1800 void do_tag(int tag) {
1801 int old_tag;
1802 old_tag = (int)(intptr_t)nextPtr();
1803 // do_int(&old_tag);
1804 assert(tag == old_tag, "old tag doesn't match");
1805 FileMapInfo::assert_mark(tag == old_tag);
1806 }
1807
1808 void do_region(u_char* start, size_t size) {
1809 assert((intptr_t)start % sizeof(intptr_t) == 0, "bad alignment");
1810 assert(size % sizeof(intptr_t) == 0, "bad size");
1811 do_tag((int)size);
1812 while (size > 0) {
1813 *(intptr_t*)start = nextPtr();
1814 start += sizeof(intptr_t);
1815 size -= sizeof(intptr_t);
1816 }
1817 }
1818
1819 bool reading() const { return true; }
1820 };
1821
1822 // Return true if given address is in the mapped shared space.
1823 bool MetaspaceShared::is_in_shared_space(const void* p) {
1824 return UseSharedSpaces && FileMapInfo::current_info()->is_in_shared_space(p);
1825 }
1826
1827 // Return true if given address is in the misc data region
1828 bool MetaspaceShared::is_in_shared_region(const void* p, int idx) {
1829 return UseSharedSpaces && FileMapInfo::current_info()->is_in_shared_region(p, idx);
1830 }
1831
1832 bool MetaspaceShared::is_in_trampoline_frame(address addr) {
1833 if (UseSharedSpaces && is_in_shared_region(addr, MetaspaceShared::mc)) {
1834 return true;
1835 }
1836 return false;
1837 }
1838
1839 void MetaspaceShared::print_shared_spaces() {
1840 if (UseSharedSpaces) {
1841 FileMapInfo::current_info()->print_shared_spaces();
1842 }
1843 }
1844
1845
1846 // Map shared spaces at requested addresses and return if succeeded.
1847 bool MetaspaceShared::map_shared_spaces(FileMapInfo* mapinfo) {
1848 size_t image_alignment = mapinfo->alignment();
1849
1850 #ifndef _WINDOWS
1851 // Map in the shared memory and then map the regions on top of it.
1852 // On Windows, don't map the memory here because it will cause the
1853 // mappings of the regions to fail.
1854 ReservedSpace shared_rs = mapinfo->reserve_shared_memory();
1855 if (!shared_rs.is_reserved()) return false;
1856 #endif
1857
1858 assert(!DumpSharedSpaces, "Should not be called with DumpSharedSpaces");
1859
1860 char* _ro_base = NULL;
1861 char* _rw_base = NULL;
1862 char* _mc_base = NULL;
1863 char* _md_base = NULL;
1864 char* _od_base = NULL;
1865
1866 // Map each shared region
1867 if ((_mc_base = mapinfo->map_region(mc)) != NULL &&
1868 mapinfo->verify_region_checksum(mc) &&
1869 (_rw_base = mapinfo->map_region(rw)) != NULL &&
1870 mapinfo->verify_region_checksum(rw) &&
1871 (_ro_base = mapinfo->map_region(ro)) != NULL &&
1872 mapinfo->verify_region_checksum(ro) &&
1873 (_md_base = mapinfo->map_region(md)) != NULL &&
1874 mapinfo->verify_region_checksum(md) &&
1875 (_od_base = mapinfo->map_region(od)) != NULL &&
1876 mapinfo->verify_region_checksum(od) &&
1877 (image_alignment == (size_t)os::vm_allocation_granularity()) &&
1878 mapinfo->validate_classpath_entry_table()) {
1879 // Success (no need to do anything)
1880 return true;
1881 } else {
1882 // If there was a failure in mapping any of the spaces, unmap the ones
1883 // that succeeded
1884 if (_ro_base != NULL) mapinfo->unmap_region(ro);
1885 if (_rw_base != NULL) mapinfo->unmap_region(rw);
1886 if (_mc_base != NULL) mapinfo->unmap_region(mc);
1887 if (_md_base != NULL) mapinfo->unmap_region(md);
1888 if (_od_base != NULL) mapinfo->unmap_region(od);
1889 #ifndef _WINDOWS
1890 // Release the entire mapped region
1891 shared_rs.release();
1892 #endif
1893 // If -Xshare:on is specified, print out the error message and exit VM,
1894 // otherwise, set UseSharedSpaces to false and continue.
1895 if (RequireSharedSpaces || PrintSharedArchiveAndExit) {
1896 vm_exit_during_initialization("Unable to use shared archive.", "Failed map_region for using -Xshare:on.");
1897 } else {
1898 FLAG_SET_DEFAULT(UseSharedSpaces, false);
1899 }
1900 return false;
1901 }
1902 }
1903
1904 // Read the miscellaneous data from the shared file, and
1905 // serialize it out to its various destinations.
1906
1907 void MetaspaceShared::initialize_shared_spaces() {
1908 FileMapInfo *mapinfo = FileMapInfo::current_info();
1909 _cds_i2i_entry_code_buffers = mapinfo->cds_i2i_entry_code_buffers();
1910 _cds_i2i_entry_code_buffers_size = mapinfo->cds_i2i_entry_code_buffers_size();
1911 _core_spaces_size = mapinfo->core_spaces_size();
1912 char* buffer = mapinfo->misc_data_patching_start();
1913 clone_cpp_vtables((intptr_t*)buffer);
1914
1915 // The rest of the data is now stored in the RW region
1916 buffer = mapinfo->read_only_tables_start();
1917 int sharedDictionaryLen = *(intptr_t*)buffer;
1918 buffer += sizeof(intptr_t);
1919 int number_of_entries = *(intptr_t*)buffer;
1920 buffer += sizeof(intptr_t);
1921 SystemDictionary::set_shared_dictionary((HashtableBucket<mtClass>*)buffer,
1922 sharedDictionaryLen,
1923 number_of_entries);
1924 buffer += sharedDictionaryLen;
1925
1926 // The following data are the linked list elements
1927 // (HashtableEntry objects) for the shared dictionary table.
1928
1929 int len = *(intptr_t*)buffer; // skip over shared dictionary entries
1930 buffer += sizeof(intptr_t);
1931 buffer += len;
1932
1933 // Verify various attributes of the archive, plus initialize the
1934 // shared string/symbol tables
1935 intptr_t* array = (intptr_t*)buffer;
1936 ReadClosure rc(&array);
1937 serialize(&rc);
1938
1939 // Initialize the run-time symbol table.
1940 SymbolTable::create_table();
1941
1942 // Close the mapinfo file
1943 mapinfo->close();
1944
1945 if (PrintSharedArchiveAndExit) {
1946 if (PrintSharedDictionary) {
1947 tty->print_cr("\nShared classes:\n");
1948 SystemDictionary::print_shared(tty);
1949 }
1950 if (_archive_loading_failed) {
1951 tty->print_cr("archive is invalid");
1952 vm_exit(1);
1953 } else {
1954 tty->print_cr("archive is valid");
1955 vm_exit(0);
1956 }
1957 }
1958 }
1959
1960 // JVM/TI RedefineClasses() support:
1961 bool MetaspaceShared::remap_shared_readonly_as_readwrite() {
1962 assert(SafepointSynchronize::is_at_safepoint(), "must be at safepoint");
1963
1964 if (UseSharedSpaces) {
1965 // remap the shared readonly space to shared readwrite, private
1966 FileMapInfo* mapinfo = FileMapInfo::current_info();
1967 if (!mapinfo->remap_shared_readonly_as_readwrite()) {
1968 return false;
1969 }
1970 _remapped_readwrite = true;
1971 }
1972 return true;
1973 }
1974
1975 void MetaspaceShared::report_out_of_space(const char* name, size_t needed_bytes) {
1976 // This is highly unlikely to happen on 64-bits because we have reserved a 4GB space.
1977 // On 32-bit we reserve only 256MB so you could run out of space with 100,000 classes
1978 // or so.
1979 _mc_region.print_out_of_space_msg(name, needed_bytes);
1980 _rw_region.print_out_of_space_msg(name, needed_bytes);
1981 _ro_region.print_out_of_space_msg(name, needed_bytes);
1982 _md_region.print_out_of_space_msg(name, needed_bytes);
1983 _od_region.print_out_of_space_msg(name, needed_bytes);
1984
1985 vm_exit_during_initialization(err_msg("Unable to allocate from '%s' region", name),
1986 "Please reduce the number of shared classes.");
1987 }