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/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 #endif
42 #include "gc/shared/gcLocker.hpp"
43 #include "interpreter/bytecodeStream.hpp"
44 #include "interpreter/bytecodes.hpp"
45 #include "logging/log.hpp"
46 #include "logging/logMessage.hpp"
47 #include "memory/filemap.hpp"
48 #include "memory/metaspace.hpp"
49 #include "memory/metaspaceShared.hpp"
50 #include "memory/resourceArea.hpp"
51 #include "oops/instanceClassLoaderKlass.hpp"
52 #include "oops/instanceMirrorKlass.hpp"
53 #include "oops/instanceRefKlass.hpp"
54 #include "oops/objArrayKlass.hpp"
55 #include "oops/objArrayOop.hpp"
56 #include "oops/oop.inline.hpp"
57 #include "oops/typeArrayKlass.hpp"
58 #include "prims/jvmtiRedefineClasses.hpp"
59 #include "runtime/timerTrace.hpp"
60 #include "runtime/os.hpp"
61 #include "runtime/signature.hpp"
62 #include "runtime/vmThread.hpp"
63 #include "runtime/vm_operations.hpp"
64 #include "utilities/align.hpp"
65 #include "utilities/defaultStream.hpp"
66 #include "utilities/hashtable.inline.hpp"
67 #include "memory/metaspaceClosure.hpp"
68
69 ReservedSpace MetaspaceShared::_shared_rs;
70 VirtualSpace MetaspaceShared::_shared_vs;
71 MetaspaceSharedStats MetaspaceShared::_stats;
72 bool MetaspaceShared::_has_error_classes;
73 bool MetaspaceShared::_archive_loading_failed = false;
74 bool MetaspaceShared::_remapped_readwrite = false;
75 bool MetaspaceShared::_open_archive_heap_region_mapped = false;
76 address MetaspaceShared::_cds_i2i_entry_code_buffers = NULL;
77 size_t MetaspaceShared::_cds_i2i_entry_code_buffers_size = 0;
78 size_t MetaspaceShared::_core_spaces_size = 0;
79
80 // The CDS archive is divided into the following regions:
81 // mc - misc code (the method entry trampolines)
82 // rw - read-write metadata
83 // ro - read-only metadata and read-only tables
84 // md - misc data (the c++ vtables)
85 // od - optional data (original class files)
86 //
87 // s0 - shared strings(closed archive heap space) #0
88 // s1 - shared strings(closed archive heap space) #1 (may be empty)
89 // oa0 - open archive heap space #0
90 // oa1 - open archive heap space #1 (may be empty)
91 //
92 // The mc, rw, ro, md and od regions are linearly allocated, starting from
93 // SharedBaseAddress, in the order of mc->rw->ro->md->od. The size of these 5 regions
94 // are page-aligned, and there's no gap between any consecutive regions.
95 //
96 // These 5 regions are populated in the following steps:
97 // [1] All classes are loaded in MetaspaceShared::preload_classes(). All metadata are
98 // temporarily allocated outside of the shared regions. Only the method entry
99 // trampolines are written into the mc region.
100 // [2] ArchiveCompactor copies RW metadata into the rw region.
101 // [3] ArchiveCompactor copies RO metadata into the ro region.
102 // [4] SymbolTable, StringTable, SystemDictionary, and a few other read-only data
103 // are copied into the ro region as read-only tables.
104 // [5] C++ vtables are copied into the md region.
105 // [6] Original class files are copied into the od region.
106 //
107 // The s0/s1 and oa0/oa1 regions are populated inside MetaspaceShared::dump_java_heap_objects.
108 // Their layout is independent of the other 5 regions.
109
110 class DumpRegion {
111 private:
112 const char* _name;
113 char* _base;
114 char* _top;
115 char* _end;
116 bool _is_packed;
117
118 char* expand_top_to(char* newtop) {
119 assert(is_allocatable(), "must be initialized and not packed");
120 assert(newtop >= _top, "must not grow backwards");
121 if (newtop > _end) {
122 MetaspaceShared::report_out_of_space(_name, newtop - _top);
123 ShouldNotReachHere();
124 }
125 MetaspaceShared::commit_shared_space_to(newtop);
126 _top = newtop;
127 return _top;
128 }
129
130 public:
131 DumpRegion(const char* name) : _name(name), _base(NULL), _top(NULL), _end(NULL), _is_packed(false) {}
132
133 char* allocate(size_t num_bytes, size_t alignment=BytesPerWord) {
134 char* p = (char*)align_up(_top, alignment);
135 char* newtop = p + align_up(num_bytes, alignment);
136 expand_top_to(newtop);
137 memset(p, 0, newtop - p);
138 return p;
139 }
140
141 void append_intptr_t(intptr_t n) {
142 assert(is_aligned(_top, sizeof(intptr_t)), "bad alignment");
143 intptr_t *p = (intptr_t*)_top;
144 char* newtop = _top + sizeof(intptr_t);
145 expand_top_to(newtop);
146 *p = n;
147 }
148
149 char* base() const { return _base; }
150 char* top() const { return _top; }
151 char* end() const { return _end; }
152 size_t reserved() const { return _end - _base; }
153 size_t used() const { return _top - _base; }
154 bool is_packed() const { return _is_packed; }
155 bool is_allocatable() const {
156 return !is_packed() && _base != NULL;
157 }
158
159 void print(size_t total_bytes) const {
160 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,
161 _name, used(), percent_of(used(), total_bytes), reserved(), percent_of(used(), reserved()), p2i(_base));
162 }
163 void print_out_of_space_msg(const char* failing_region, size_t needed_bytes) {
164 tty->print("[%-8s] " PTR_FORMAT " - " PTR_FORMAT " capacity =%9d, allocated =%9d",
165 _name, p2i(_base), p2i(_top), int(_end - _base), int(_top - _base));
166 if (strcmp(_name, failing_region) == 0) {
167 tty->print_cr(" required = %d", int(needed_bytes));
168 } else {
169 tty->cr();
170 }
171 }
172
173 void init(const ReservedSpace* rs) {
174 _base = _top = rs->base();
175 _end = rs->end();
176 }
177 void init(char* b, char* t, char* e) {
178 _base = b;
179 _top = t;
180 _end = e;
181 }
182
183 void pack(DumpRegion* next = NULL) {
184 assert(!is_packed(), "sanity");
185 _end = (char*)align_up(_top, Metaspace::reserve_alignment());
186 _is_packed = true;
187 if (next != NULL) {
188 next->_base = next->_top = this->_end;
189 next->_end = MetaspaceShared::shared_rs()->end();
190 }
191 }
192 bool contains(char* p) {
193 return base() <= p && p < top();
194 }
195 };
196
197
198 DumpRegion _mc_region("mc"), _ro_region("ro"), _rw_region("rw"), _md_region("md"), _od_region("od");
199 size_t _total_string_region_size = 0, _total_open_archive_region_size = 0;
200
201 char* MetaspaceShared::misc_code_space_alloc(size_t num_bytes) {
202 return _mc_region.allocate(num_bytes);
203 }
204
205 char* MetaspaceShared::read_only_space_alloc(size_t num_bytes) {
206 return _ro_region.allocate(num_bytes);
207 }
208
209 void MetaspaceShared::initialize_runtime_shared_and_meta_spaces() {
210 assert(UseSharedSpaces, "Must be called when UseSharedSpaces is enabled");
211
212 // If using shared space, open the file that contains the shared space
213 // and map in the memory before initializing the rest of metaspace (so
214 // the addresses don't conflict)
215 address cds_address = NULL;
216 FileMapInfo* mapinfo = new FileMapInfo();
217
218 // Open the shared archive file, read and validate the header. If
219 // initialization fails, shared spaces [UseSharedSpaces] are
220 // disabled and the file is closed.
221 // Map in spaces now also
222 if (mapinfo->initialize() && map_shared_spaces(mapinfo)) {
223 size_t cds_total = core_spaces_size();
224 cds_address = (address)mapinfo->header()->region_addr(0);
225 #ifdef _LP64
226 if (Metaspace::using_class_space()) {
227 char* cds_end = (char*)(cds_address + cds_total);
228 cds_end = (char *)align_up(cds_end, Metaspace::reserve_alignment());
229 // If UseCompressedClassPointers is set then allocate the metaspace area
230 // above the heap and above the CDS area (if it exists).
231 Metaspace::allocate_metaspace_compressed_klass_ptrs(cds_end, cds_address);
232 // map_heap_regions() compares the current narrow oop and klass encodings
233 // with the archived ones, so it must be done after all encodings are determined.
234 mapinfo->map_heap_regions();
235 }
236 #endif // _LP64
237 } else {
238 assert(!mapinfo->is_open() && !UseSharedSpaces,
239 "archive file not closed or shared spaces not disabled.");
240 }
241 }
242
243 void MetaspaceShared::initialize_dumptime_shared_and_meta_spaces() {
244 assert(DumpSharedSpaces, "should be called for dump time only");
245 const size_t reserve_alignment = Metaspace::reserve_alignment();
246 bool large_pages = false; // No large pages when dumping the CDS archive.
247 char* shared_base = (char*)align_up((char*)SharedBaseAddress, reserve_alignment);
248
249 #ifdef _LP64
250 // On 64-bit VM, the heap and class space layout will be the same as if
251 // you're running in -Xshare:on mode:
252 //
253 // +-- SharedBaseAddress (default = 0x800000000)
254 // v
255 // +-..---------+---------+ ... +----+----+----+----+----+---------------+
256 // | Heap | Archive | | MC | RW | RO | MD | OD | class space |
257 // +-..---------+---------+ ... +----+----+----+----+----+---------------+
258 // |<-- MaxHeapSize -->| |<-- UnscaledClassSpaceMax = 4GB ------->|
259 //
260 const uint64_t UnscaledClassSpaceMax = (uint64_t(max_juint) + 1);
261 const size_t cds_total = align_down(UnscaledClassSpaceMax, reserve_alignment);
262 #else
263 // We don't support archives larger than 256MB on 32-bit due to limited virtual address space.
264 size_t cds_total = align_down(256*M, reserve_alignment);
265 #endif
266
267 // First try to reserve the space at the specified SharedBaseAddress.
268 _shared_rs = ReservedSpace(cds_total, reserve_alignment, large_pages, shared_base);
269 if (_shared_rs.is_reserved()) {
270 assert(shared_base == 0 || _shared_rs.base() == shared_base, "should match");
271 } else {
272 // Get a mmap region anywhere if the SharedBaseAddress fails.
273 _shared_rs = ReservedSpace(cds_total, reserve_alignment, large_pages);
274 }
275 if (!_shared_rs.is_reserved()) {
276 vm_exit_during_initialization("Unable to reserve memory for shared space",
277 err_msg(SIZE_FORMAT " bytes.", cds_total));
278 }
279
280 #ifdef _LP64
281 // During dump time, we allocate 4GB (UnscaledClassSpaceMax) of space and split it up:
282 // + The upper 1 GB is used as the "temporary compressed class space" -- preload_classes()
283 // will store Klasses into this space.
284 // + The lower 3 GB is used for the archive -- when preload_classes() is done,
285 // ArchiveCompactor will copy the class metadata into this space, first the RW parts,
286 // then the RO parts.
287
288 assert(UseCompressedOops && UseCompressedClassPointers,
289 "UseCompressedOops and UseCompressedClassPointers must be set");
290
291 size_t max_archive_size = align_down(cds_total * 3 / 4, reserve_alignment);
292 ReservedSpace tmp_class_space = _shared_rs.last_part(max_archive_size);
293 CompressedClassSpaceSize = align_down(tmp_class_space.size(), reserve_alignment);
294 _shared_rs = _shared_rs.first_part(max_archive_size);
295
296 // Set up compress class pointers.
297 Universe::set_narrow_klass_base((address)_shared_rs.base());
298 // Set narrow_klass_shift to be LogKlassAlignmentInBytes. This is consistent
299 // with AOT.
300 Universe::set_narrow_klass_shift(LogKlassAlignmentInBytes);
301
302 Metaspace::initialize_class_space(tmp_class_space);
303 tty->print_cr("narrow_klass_base = " PTR_FORMAT ", narrow_klass_shift = %d",
304 p2i(Universe::narrow_klass_base()), Universe::narrow_klass_shift());
305
306 tty->print_cr("Allocated temporary class space: " SIZE_FORMAT " bytes at " PTR_FORMAT,
307 CompressedClassSpaceSize, p2i(tmp_class_space.base()));
308 #endif
309
310 // Start with 0 committed bytes. The memory will be committed as needed by
311 // MetaspaceShared::commit_shared_space_to().
312 if (!_shared_vs.initialize(_shared_rs, 0)) {
313 vm_exit_during_initialization("Unable to allocate memory for shared space");
314 }
315
316 _mc_region.init(&_shared_rs);
317 tty->print_cr("Allocated shared space: " SIZE_FORMAT " bytes at " PTR_FORMAT,
318 _shared_rs.size(), p2i(_shared_rs.base()));
319 }
320
321 void MetaspaceShared::commit_shared_space_to(char* newtop) {
322 assert(DumpSharedSpaces, "dump-time only");
323 char* base = _shared_rs.base();
324 size_t need_committed_size = newtop - base;
325 size_t has_committed_size = _shared_vs.committed_size();
326 if (need_committed_size < has_committed_size) {
327 return;
328 }
329
330 size_t min_bytes = need_committed_size - has_committed_size;
331 size_t preferred_bytes = 1 * M;
332 size_t uncommitted = _shared_vs.reserved_size() - has_committed_size;
333
334 size_t commit = MAX2(min_bytes, preferred_bytes);
335 assert(commit <= uncommitted, "sanity");
336
337 bool result = _shared_vs.expand_by(commit, false);
338 if (!result) {
339 vm_exit_during_initialization(err_msg("Failed to expand shared space to " SIZE_FORMAT " bytes",
340 need_committed_size));
341 }
342
343 log_info(cds)("Expanding shared spaces by " SIZE_FORMAT_W(7) " bytes [total " SIZE_FORMAT_W(9) " bytes ending at %p]",
344 commit, _shared_vs.actual_committed_size(), _shared_vs.high());
345 }
346
347 // Read/write a data stream for restoring/preserving metadata pointers and
348 // miscellaneous data from/to the shared archive file.
349
350 void MetaspaceShared::serialize(SerializeClosure* soc) {
351 int tag = 0;
352 soc->do_tag(--tag);
353
354 // Verify the sizes of various metadata in the system.
355 soc->do_tag(sizeof(Method));
356 soc->do_tag(sizeof(ConstMethod));
357 soc->do_tag(arrayOopDesc::base_offset_in_bytes(T_BYTE));
358 soc->do_tag(sizeof(ConstantPool));
359 soc->do_tag(sizeof(ConstantPoolCache));
360 soc->do_tag(objArrayOopDesc::base_offset_in_bytes());
361 soc->do_tag(typeArrayOopDesc::base_offset_in_bytes(T_BYTE));
362 soc->do_tag(sizeof(Symbol));
363
364 // Dump/restore miscellaneous metadata.
365 Universe::serialize(soc, true);
366 soc->do_tag(--tag);
367
368 // Dump/restore references to commonly used names and signatures.
369 vmSymbols::serialize(soc);
370 soc->do_tag(--tag);
371
372 // Dump/restore the symbol and string tables
373 SymbolTable::serialize(soc);
374 StringTable::serialize(soc);
375 soc->do_tag(--tag);
376
377 soc->do_tag(666);
378 }
379
380 address MetaspaceShared::cds_i2i_entry_code_buffers(size_t total_size) {
381 if (DumpSharedSpaces) {
382 if (_cds_i2i_entry_code_buffers == NULL) {
383 _cds_i2i_entry_code_buffers = (address)misc_code_space_alloc(total_size);
384 _cds_i2i_entry_code_buffers_size = total_size;
385 }
386 } else if (UseSharedSpaces) {
387 assert(_cds_i2i_entry_code_buffers != NULL, "must already been initialized");
388 } else {
389 return NULL;
390 }
391
392 assert(_cds_i2i_entry_code_buffers_size == total_size, "must not change");
393 return _cds_i2i_entry_code_buffers;
394 }
395
396 // CDS code for dumping shared archive.
397
398 // Global object for holding classes that have been loaded. Since this
399 // is run at a safepoint just before exit, this is the entire set of classes.
400 static GrowableArray<Klass*>* _global_klass_objects;
401
402 static void collect_array_classes(Klass* k) {
403 _global_klass_objects->append_if_missing(k);
404 if (k->is_array_klass()) {
405 // Add in the array classes too
406 ArrayKlass* ak = ArrayKlass::cast(k);
407 Klass* h = ak->higher_dimension();
408 if (h != NULL) {
409 h->array_klasses_do(collect_array_classes);
410 }
411 }
412 }
413
414 class CollectClassesClosure : public KlassClosure {
415 void do_klass(Klass* k) {
416 if (!(k->is_instance_klass() && InstanceKlass::cast(k)->is_in_error_state())) {
417 _global_klass_objects->append_if_missing(k);
418 }
419 if (k->is_array_klass()) {
420 // Add in the array classes too
421 ArrayKlass* ak = ArrayKlass::cast(k);
422 Klass* h = ak->higher_dimension();
423 if (h != NULL) {
424 h->array_klasses_do(collect_array_classes);
425 }
426 }
427 }
428 };
429
430 static void remove_unshareable_in_classes() {
431 for (int i = 0; i < _global_klass_objects->length(); i++) {
432 Klass* k = _global_klass_objects->at(i);
433 if (!k->is_objArray_klass()) {
434 // InstanceKlass and TypeArrayKlass will in turn call remove_unshareable_info
435 // on their array classes.
436 assert(k->is_instance_klass() || k->is_typeArray_klass(), "must be");
437 k->remove_unshareable_info();
438 }
439 }
440 }
441
442 static void remove_java_mirror_in_classes() {
443 for (int i = 0; i < _global_klass_objects->length(); i++) {
444 Klass* k = _global_klass_objects->at(i);
445 if (!k->is_objArray_klass()) {
446 // InstanceKlass and TypeArrayKlass will in turn call remove_unshareable_info
447 // on their array classes.
448 assert(k->is_instance_klass() || k->is_typeArray_klass(), "must be");
449 k->remove_java_mirror();
450 }
451 }
452 }
453
454 static void rewrite_nofast_bytecode(Method* method) {
455 BytecodeStream bcs(method);
456 while (!bcs.is_last_bytecode()) {
457 Bytecodes::Code opcode = bcs.next();
458 switch (opcode) {
459 case Bytecodes::_getfield: *bcs.bcp() = Bytecodes::_nofast_getfield; break;
460 case Bytecodes::_putfield: *bcs.bcp() = Bytecodes::_nofast_putfield; break;
461 case Bytecodes::_aload_0: *bcs.bcp() = Bytecodes::_nofast_aload_0; break;
462 case Bytecodes::_iload: {
463 if (!bcs.is_wide()) {
464 *bcs.bcp() = Bytecodes::_nofast_iload;
465 }
466 break;
467 }
468 default: break;
469 }
470 }
471 }
472
473 // Walk all methods in the class list to ensure that they won't be modified at
474 // run time. This includes:
475 // [1] Rewrite all bytecodes as needed, so that the ConstMethod* will not be modified
476 // at run time by RewriteBytecodes/RewriteFrequentPairs
477 // [2] Assign a fingerprint, so one doesn't need to be assigned at run-time.
478 static void rewrite_nofast_bytecodes_and_calculate_fingerprints() {
479 for (int i = 0; i < _global_klass_objects->length(); i++) {
480 Klass* k = _global_klass_objects->at(i);
481 if (k->is_instance_klass()) {
482 InstanceKlass* ik = InstanceKlass::cast(k);
483 for (int i = 0; i < ik->methods()->length(); i++) {
484 Method* m = ik->methods()->at(i);
485 rewrite_nofast_bytecode(m);
486 Fingerprinter fp(m);
487 // The side effect of this call sets method's fingerprint field.
488 fp.fingerprint();
489 }
490 }
491 }
492 }
493
494 static void relocate_cached_class_file() {
495 for (int i = 0; i < _global_klass_objects->length(); i++) {
496 Klass* k = _global_klass_objects->at(i);
497 if (k->is_instance_klass()) {
498 InstanceKlass* ik = InstanceKlass::cast(k);
499 JvmtiCachedClassFileData* p = ik->get_archived_class_data();
500 if (p != NULL) {
501 int size = offset_of(JvmtiCachedClassFileData, data) + p->length;
502 JvmtiCachedClassFileData* q = (JvmtiCachedClassFileData*)_od_region.allocate(size);
503 q->length = p->length;
504 memcpy(q->data, p->data, p->length);
505 ik->set_archived_class_data(q);
506 }
507 }
508 }
509 }
510
511 NOT_PRODUCT(
512 static void assert_not_anonymous_class(InstanceKlass* k) {
513 assert(!(k->is_anonymous()), "cannot archive anonymous classes");
514 }
515
516 // Anonymous classes are not stored inside any dictionaries. They are created by
517 // SystemDictionary::parse_stream() with a non-null host_klass.
518 static void assert_no_anonymoys_classes_in_dictionaries() {
519 ClassLoaderDataGraph::dictionary_classes_do(assert_not_anonymous_class);
520 })
521
522 // Objects of the Metadata types (such as Klass and ConstantPool) have C++ vtables.
523 // (In GCC this is the field <Type>::_vptr, i.e., first word in the object.)
524 //
525 // Addresses of the vtables and the methods may be different across JVM runs,
526 // if libjvm.so is dynamically loaded at a different base address.
527 //
528 // To ensure that the Metadata objects in the CDS archive always have the correct vtable:
529 //
530 // + at dump time: we redirect the _vptr to point to our own vtables inside
531 // the CDS image
532 // + at run time: we clone the actual contents of the vtables from libjvm.so
533 // into our own tables.
534
535 // Currently, the archive contain ONLY the following types of objects that have C++ vtables.
536 #define CPP_VTABLE_PATCH_TYPES_DO(f) \
537 f(ConstantPool) \
538 f(InstanceKlass) \
539 f(InstanceClassLoaderKlass) \
540 f(InstanceMirrorKlass) \
541 f(InstanceRefKlass) \
542 f(Method) \
543 f(ObjArrayKlass) \
544 f(TypeArrayKlass)
545
546 class CppVtableInfo {
547 intptr_t _vtable_size;
548 intptr_t _cloned_vtable[1];
549 public:
550 static int num_slots(int vtable_size) {
551 return 1 + vtable_size; // Need to add the space occupied by _vtable_size;
552 }
553 int vtable_size() { return int(uintx(_vtable_size)); }
554 void set_vtable_size(int n) { _vtable_size = intptr_t(n); }
555 intptr_t* cloned_vtable() { return &_cloned_vtable[0]; }
556 void zero() { memset(_cloned_vtable, 0, sizeof(intptr_t) * vtable_size()); }
557 // Returns the address of the next CppVtableInfo that can be placed immediately after this CppVtableInfo
558 static size_t byte_size(int vtable_size) {
559 CppVtableInfo i;
560 return pointer_delta(&i._cloned_vtable[vtable_size], &i, sizeof(u1));
561 }
562 };
563
564 template <class T> class CppVtableCloner : public T {
565 static intptr_t* vtable_of(Metadata& m) {
566 return *((intptr_t**)&m);
567 }
568 static CppVtableInfo* _info;
569
570 static int get_vtable_length(const char* name);
571
572 public:
573 // Allocate and initialize the C++ vtable, starting from top, but do not go past end.
574 static intptr_t* allocate(const char* name);
575
576 // Clone the vtable to ...
577 static intptr_t* clone_vtable(const char* name, CppVtableInfo* info);
578
579 static void zero_vtable_clone() {
580 assert(DumpSharedSpaces, "dump-time only");
581 _info->zero();
582 }
583
584 // Switch the vtable pointer to point to the cloned vtable.
585 static void patch(Metadata* obj) {
586 assert(DumpSharedSpaces, "dump-time only");
587 *(void**)obj = (void*)(_info->cloned_vtable());
588 }
589
590 static bool is_valid_shared_object(const T* obj) {
591 intptr_t* vptr = *(intptr_t**)obj;
592 return vptr == _info->cloned_vtable();
593 }
594 };
595
596 template <class T> CppVtableInfo* CppVtableCloner<T>::_info = NULL;
597
598 template <class T>
599 intptr_t* CppVtableCloner<T>::allocate(const char* name) {
600 assert(is_aligned(_md_region.top(), sizeof(intptr_t)), "bad alignment");
601 int n = get_vtable_length(name);
602 _info = (CppVtableInfo*)_md_region.allocate(CppVtableInfo::byte_size(n), sizeof(intptr_t));
603 _info->set_vtable_size(n);
604
605 intptr_t* p = clone_vtable(name, _info);
606 assert((char*)p == _md_region.top(), "must be");
607
608 return p;
609 }
610
611 template <class T>
612 intptr_t* CppVtableCloner<T>::clone_vtable(const char* name, CppVtableInfo* info) {
613 if (!DumpSharedSpaces) {
614 assert(_info == 0, "_info is initialized only at dump time");
615 _info = info; // Remember it -- it will be used by MetaspaceShared::is_valid_shared_method()
616 }
617 T tmp; // Allocate temporary dummy metadata object to get to the original vtable.
618 int n = info->vtable_size();
619 intptr_t* srcvtable = vtable_of(tmp);
620 intptr_t* dstvtable = info->cloned_vtable();
621
622 // We already checked (and, if necessary, adjusted n) when the vtables were allocated, so we are
623 // safe to do memcpy.
624 log_debug(cds, vtables)("Copying %3d vtable entries for %s", n, name);
625 memcpy(dstvtable, srcvtable, sizeof(intptr_t) * n);
626 return dstvtable + n;
627 }
628
629 // To determine the size of the vtable for each type, we use the following
630 // trick by declaring 2 subclasses:
631 //
632 // class CppVtableTesterA: public InstanceKlass {virtual int last_virtual_method() {return 1;} };
633 // class CppVtableTesterB: public InstanceKlass {virtual void* last_virtual_method() {return NULL}; };
634 //
635 // CppVtableTesterA and CppVtableTesterB's vtables have the following properties:
636 // - Their size (N+1) is exactly one more than the size of InstanceKlass's vtable (N)
637 // - The first N entries have are exactly the same as in InstanceKlass's vtable.
638 // - Their last entry is different.
639 //
640 // So to determine the value of N, we just walk CppVtableTesterA and CppVtableTesterB's tables
641 // and find the first entry that's different.
642 //
643 // This works on all C++ compilers supported by Oracle, but you may need to tweak it for more
644 // esoteric compilers.
645
646 template <class T> class CppVtableTesterB: public T {
647 public:
648 virtual int last_virtual_method() {return 1;}
649 };
650
651 template <class T> class CppVtableTesterA : public T {
652 public:
653 virtual void* last_virtual_method() {
654 // Make this different than CppVtableTesterB::last_virtual_method so the C++
655 // compiler/linker won't alias the two functions.
656 return NULL;
657 }
658 };
659
660 template <class T>
661 int CppVtableCloner<T>::get_vtable_length(const char* name) {
662 CppVtableTesterA<T> a;
663 CppVtableTesterB<T> b;
664
665 intptr_t* avtable = vtable_of(a);
666 intptr_t* bvtable = vtable_of(b);
667
668 // Start at slot 1, because slot 0 may be RTTI (on Solaris/Sparc)
669 int vtable_len = 1;
670 for (; ; vtable_len++) {
671 if (avtable[vtable_len] != bvtable[vtable_len]) {
672 break;
673 }
674 }
675 log_debug(cds, vtables)("Found %3d vtable entries for %s", vtable_len, name);
676
677 return vtable_len;
678 }
679
680 #define ALLOC_CPP_VTABLE_CLONE(c) \
681 CppVtableCloner<c>::allocate(#c);
682
683 #define CLONE_CPP_VTABLE(c) \
684 p = CppVtableCloner<c>::clone_vtable(#c, (CppVtableInfo*)p);
685
686 #define ZERO_CPP_VTABLE(c) \
687 CppVtableCloner<c>::zero_vtable_clone();
688
689 // This can be called at both dump time and run time.
690 intptr_t* MetaspaceShared::clone_cpp_vtables(intptr_t* p) {
691 assert(DumpSharedSpaces || UseSharedSpaces, "sanity");
692 CPP_VTABLE_PATCH_TYPES_DO(CLONE_CPP_VTABLE);
693 return p;
694 }
695
696 void MetaspaceShared::zero_cpp_vtable_clones_for_writing() {
697 assert(DumpSharedSpaces, "dump-time only");
698 CPP_VTABLE_PATCH_TYPES_DO(ZERO_CPP_VTABLE);
699 }
700
701 // Allocate and initialize the C++ vtables, starting from top, but do not go past end.
702 void MetaspaceShared::allocate_cpp_vtable_clones() {
703 assert(DumpSharedSpaces, "dump-time only");
704 // Layout (each slot is a intptr_t):
705 // [number of slots in the first vtable = n1]
706 // [ <n1> slots for the first vtable]
707 // [number of slots in the first second = n2]
708 // [ <n2> slots for the second vtable]
709 // ...
710 // The order of the vtables is the same as the CPP_VTAB_PATCH_TYPES_DO macro.
711 CPP_VTABLE_PATCH_TYPES_DO(ALLOC_CPP_VTABLE_CLONE);
712 }
713
714 // Switch the vtable pointer to point to the cloned vtable. We assume the
715 // vtable pointer is in first slot in object.
716 void MetaspaceShared::patch_cpp_vtable_pointers() {
717 int n = _global_klass_objects->length();
718 for (int i = 0; i < n; i++) {
719 Klass* obj = _global_klass_objects->at(i);
720 if (obj->is_instance_klass()) {
721 InstanceKlass* ik = InstanceKlass::cast(obj);
722 if (ik->is_class_loader_instance_klass()) {
723 CppVtableCloner<InstanceClassLoaderKlass>::patch(ik);
724 } else if (ik->is_reference_instance_klass()) {
725 CppVtableCloner<InstanceRefKlass>::patch(ik);
726 } else if (ik->is_mirror_instance_klass()) {
727 CppVtableCloner<InstanceMirrorKlass>::patch(ik);
728 } else {
729 CppVtableCloner<InstanceKlass>::patch(ik);
730 }
731 ConstantPool* cp = ik->constants();
732 CppVtableCloner<ConstantPool>::patch(cp);
733 for (int j = 0; j < ik->methods()->length(); j++) {
734 Method* m = ik->methods()->at(j);
735 CppVtableCloner<Method>::patch(m);
736 assert(CppVtableCloner<Method>::is_valid_shared_object(m), "must be");
737 }
738 } else if (obj->is_objArray_klass()) {
739 CppVtableCloner<ObjArrayKlass>::patch(obj);
740 } else {
741 assert(obj->is_typeArray_klass(), "sanity");
742 CppVtableCloner<TypeArrayKlass>::patch(obj);
743 }
744 }
745 }
746
747 bool MetaspaceShared::is_valid_shared_method(const Method* m) {
748 assert(is_in_shared_metaspace(m), "must be");
749 return CppVtableCloner<Method>::is_valid_shared_object(m);
750 }
751
752 // Closure for serializing initialization data out to a data area to be
753 // written to the shared file.
754
755 class WriteClosure : public SerializeClosure {
756 private:
757 DumpRegion* _dump_region;
758
759 public:
760 WriteClosure(DumpRegion* r) {
761 _dump_region = r;
762 }
763
764 void do_ptr(void** p) {
765 _dump_region->append_intptr_t((intptr_t)*p);
766 }
767
768 void do_u4(u4* p) {
769 void* ptr = (void*)(uintx(*p));
770 do_ptr(&ptr);
771 }
772
773 void do_tag(int tag) {
774 _dump_region->append_intptr_t((intptr_t)tag);
775 }
776
777 void do_region(u_char* start, size_t size) {
778 assert((intptr_t)start % sizeof(intptr_t) == 0, "bad alignment");
779 assert(size % sizeof(intptr_t) == 0, "bad size");
780 do_tag((int)size);
781 while (size > 0) {
782 _dump_region->append_intptr_t(*(intptr_t*)start);
783 start += sizeof(intptr_t);
784 size -= sizeof(intptr_t);
785 }
786 }
787
788 bool reading() const { return false; }
789 };
790
791 // This is for dumping detailed statistics for the allocations
792 // in the shared spaces.
793 class DumpAllocStats : public ResourceObj {
794 public:
795
796 // Here's poor man's enum inheritance
797 #define SHAREDSPACE_OBJ_TYPES_DO(f) \
798 METASPACE_OBJ_TYPES_DO(f) \
799 f(SymbolHashentry) \
800 f(SymbolBucket) \
801 f(StringHashentry) \
802 f(StringBucket) \
803 f(Other)
804
805 enum Type {
806 // Types are MetaspaceObj::ClassType, MetaspaceObj::SymbolType, etc
807 SHAREDSPACE_OBJ_TYPES_DO(METASPACE_OBJ_TYPE_DECLARE)
808 _number_of_types
809 };
810
811 static const char * type_name(Type type) {
812 switch(type) {
813 SHAREDSPACE_OBJ_TYPES_DO(METASPACE_OBJ_TYPE_NAME_CASE)
814 default:
815 ShouldNotReachHere();
816 return NULL;
817 }
818 }
819
820 public:
821 enum { RO = 0, RW = 1 };
822
823 int _counts[2][_number_of_types];
824 int _bytes [2][_number_of_types];
825
826 DumpAllocStats() {
827 memset(_counts, 0, sizeof(_counts));
828 memset(_bytes, 0, sizeof(_bytes));
829 };
830
831 void record(MetaspaceObj::Type type, int byte_size, bool read_only) {
832 assert(int(type) >= 0 && type < MetaspaceObj::_number_of_types, "sanity");
833 int which = (read_only) ? RO : RW;
834 _counts[which][type] ++;
835 _bytes [which][type] += byte_size;
836 }
837
838 void record_other_type(int byte_size, bool read_only) {
839 int which = (read_only) ? RO : RW;
840 _bytes [which][OtherType] += byte_size;
841 }
842 void print_stats(int ro_all, int rw_all, int mc_all, int md_all);
843 };
844
845 void DumpAllocStats::print_stats(int ro_all, int rw_all, int mc_all, int md_all) {
846 // Calculate size of data that was not allocated by Metaspace::allocate()
847 MetaspaceSharedStats *stats = MetaspaceShared::stats();
848
849 // symbols
850 _counts[RO][SymbolHashentryType] = stats->symbol.hashentry_count;
851 _bytes [RO][SymbolHashentryType] = stats->symbol.hashentry_bytes;
852
853 _counts[RO][SymbolBucketType] = stats->symbol.bucket_count;
854 _bytes [RO][SymbolBucketType] = stats->symbol.bucket_bytes;
855
856 // strings
857 _counts[RO][StringHashentryType] = stats->string.hashentry_count;
858 _bytes [RO][StringHashentryType] = stats->string.hashentry_bytes;
859
860 _counts[RO][StringBucketType] = stats->string.bucket_count;
861 _bytes [RO][StringBucketType] = stats->string.bucket_bytes;
862
863 // TODO: count things like dictionary, vtable, etc
864 _bytes[RW][OtherType] += mc_all + md_all;
865 rw_all += mc_all + md_all; // mc/md are mapped Read/Write
866
867 // prevent divide-by-zero
868 if (ro_all < 1) {
869 ro_all = 1;
870 }
871 if (rw_all < 1) {
872 rw_all = 1;
873 }
874
875 int all_ro_count = 0;
876 int all_ro_bytes = 0;
877 int all_rw_count = 0;
878 int all_rw_bytes = 0;
879
880 // To make fmt_stats be a syntactic constant (for format warnings), use #define.
881 #define fmt_stats "%-20s: %8d %10d %5.1f | %8d %10d %5.1f | %8d %10d %5.1f"
882 const char *sep = "--------------------+---------------------------+---------------------------+--------------------------";
883 const char *hdr = " ro_cnt ro_bytes % | rw_cnt rw_bytes % | all_cnt all_bytes %";
884
885 LogMessage(cds) msg;
886
887 msg.info("Detailed metadata info (excluding od/st regions; rw stats include md/mc regions):");
888 msg.info("%s", hdr);
889 msg.info("%s", sep);
890 for (int type = 0; type < int(_number_of_types); type ++) {
891 const char *name = type_name((Type)type);
892 int ro_count = _counts[RO][type];
893 int ro_bytes = _bytes [RO][type];
894 int rw_count = _counts[RW][type];
895 int rw_bytes = _bytes [RW][type];
896 int count = ro_count + rw_count;
897 int bytes = ro_bytes + rw_bytes;
898
899 double ro_perc = percent_of(ro_bytes, ro_all);
900 double rw_perc = percent_of(rw_bytes, rw_all);
901 double perc = percent_of(bytes, ro_all + rw_all);
902
903 msg.info(fmt_stats, name,
904 ro_count, ro_bytes, ro_perc,
905 rw_count, rw_bytes, rw_perc,
906 count, bytes, perc);
907
908 all_ro_count += ro_count;
909 all_ro_bytes += ro_bytes;
910 all_rw_count += rw_count;
911 all_rw_bytes += rw_bytes;
912 }
913
914 int all_count = all_ro_count + all_rw_count;
915 int all_bytes = all_ro_bytes + all_rw_bytes;
916
917 double all_ro_perc = percent_of(all_ro_bytes, ro_all);
918 double all_rw_perc = percent_of(all_rw_bytes, rw_all);
919 double all_perc = percent_of(all_bytes, ro_all + rw_all);
920
921 msg.info("%s", sep);
922 msg.info(fmt_stats, "Total",
923 all_ro_count, all_ro_bytes, all_ro_perc,
924 all_rw_count, all_rw_bytes, all_rw_perc,
925 all_count, all_bytes, all_perc);
926
927 assert(all_ro_bytes == ro_all, "everything should have been counted");
928 assert(all_rw_bytes == rw_all, "everything should have been counted");
929
930 #undef fmt_stats
931 }
932
933 // Populate the shared space.
934
935 class VM_PopulateDumpSharedSpace: public VM_Operation {
936 private:
937 GrowableArray<MemRegion> *_string_regions;
938 GrowableArray<MemRegion> *_open_archive_heap_regions;
939
940 void dump_java_heap_objects() NOT_CDS_JAVA_HEAP_RETURN;
941 void dump_symbols();
942 char* dump_read_only_tables();
943 void print_region_stats();
944 void print_heap_region_stats(GrowableArray<MemRegion> *heap_mem,
945 const char *name, const size_t total_size);
946 public:
947
948 VMOp_Type type() const { return VMOp_PopulateDumpSharedSpace; }
949 void doit(); // outline because gdb sucks
950 static void write_region(FileMapInfo* mapinfo, int region, DumpRegion* space, bool read_only, bool allow_exec);
951 }; // class VM_PopulateDumpSharedSpace
952
953 class SortedSymbolClosure: public SymbolClosure {
954 GrowableArray<Symbol*> _symbols;
955 virtual void do_symbol(Symbol** sym) {
956 assert((*sym)->is_permanent(), "archived symbols must be permanent");
957 _symbols.append(*sym);
958 }
959 static int compare_symbols_by_address(Symbol** a, Symbol** b) {
960 if (a[0] < b[0]) {
961 return -1;
962 } else if (a[0] == b[0]) {
963 return 0;
964 } else {
965 return 1;
966 }
967 }
968
969 public:
970 SortedSymbolClosure() {
971 SymbolTable::symbols_do(this);
972 _symbols.sort(compare_symbols_by_address);
973 }
974 GrowableArray<Symbol*>* get_sorted_symbols() {
975 return &_symbols;
976 }
977 };
978
979 // ArchiveCompactor --
980 //
981 // This class is the central piece of shared archive compaction -- all metaspace data are
982 // initially allocated outside of the shared regions. ArchiveCompactor copies the
983 // metaspace data into their final location in the shared regions.
984
985 class ArchiveCompactor : AllStatic {
986 static DumpAllocStats* _alloc_stats;
987 static SortedSymbolClosure* _ssc;
988
989 static unsigned my_hash(const address& a) {
990 return primitive_hash<address>(a);
991 }
992 static bool my_equals(const address& a0, const address& a1) {
993 return primitive_equals<address>(a0, a1);
994 }
995 typedef ResourceHashtable<
996 address, address,
997 ArchiveCompactor::my_hash, // solaris compiler doesn't like: primitive_hash<address>
998 ArchiveCompactor::my_equals, // solaris compiler doesn't like: primitive_equals<address>
999 16384, ResourceObj::C_HEAP> RelocationTable;
1000 static RelocationTable* _new_loc_table;
1001
1002 public:
1003 static void initialize() {
1004 _alloc_stats = new(ResourceObj::C_HEAP, mtInternal)DumpAllocStats;
1005 _new_loc_table = new(ResourceObj::C_HEAP, mtInternal)RelocationTable;
1006 }
1007 static DumpAllocStats* alloc_stats() {
1008 return _alloc_stats;
1009 }
1010
1011 static void allocate(MetaspaceClosure::Ref* ref, bool read_only) {
1012 address obj = ref->obj();
1013 int bytes = ref->size() * BytesPerWord;
1014 char* p;
1015 size_t alignment = BytesPerWord;
1016 char* oldtop;
1017 char* newtop;
1018
1019 if (read_only) {
1020 oldtop = _ro_region.top();
1021 p = _ro_region.allocate(bytes, alignment);
1022 newtop = _ro_region.top();
1023 } else {
1024 oldtop = _rw_region.top();
1025 p = _rw_region.allocate(bytes, alignment);
1026 newtop = _rw_region.top();
1027 }
1028 memcpy(p, obj, bytes);
1029 bool isnew = _new_loc_table->put(obj, (address)p);
1030 log_trace(cds)("Copy: " PTR_FORMAT " ==> " PTR_FORMAT " %d", p2i(obj), p2i(p), bytes);
1031 assert(isnew, "must be");
1032
1033 _alloc_stats->record(ref->msotype(), int(newtop - oldtop), read_only);
1034 if (ref->msotype() == MetaspaceObj::SymbolType) {
1035 uintx delta = MetaspaceShared::object_delta(p);
1036 if (delta > MAX_SHARED_DELTA) {
1037 // This is just a sanity check and should not appear in any real world usage. This
1038 // happens only if you allocate more than 2GB of Symbols and would require
1039 // millions of shared classes.
1040 vm_exit_during_initialization("Too many Symbols in the CDS archive",
1041 "Please reduce the number of shared classes.");
1042 }
1043 }
1044 }
1045
1046 static address get_new_loc(MetaspaceClosure::Ref* ref) {
1047 address* pp = _new_loc_table->get(ref->obj());
1048 assert(pp != NULL, "must be");
1049 return *pp;
1050 }
1051
1052 private:
1053 // Makes a shallow copy of visited MetaspaceObj's
1054 class ShallowCopier: public UniqueMetaspaceClosure {
1055 bool _read_only;
1056 public:
1057 ShallowCopier(bool read_only) : _read_only(read_only) {}
1058
1059 virtual void do_unique_ref(Ref* ref, bool read_only) {
1060 if (read_only == _read_only) {
1061 allocate(ref, read_only);
1062 }
1063 }
1064 };
1065
1066 // Relocate embedded pointers within a MetaspaceObj's shallow copy
1067 class ShallowCopyEmbeddedRefRelocator: public UniqueMetaspaceClosure {
1068 public:
1069 virtual void do_unique_ref(Ref* ref, bool read_only) {
1070 address new_loc = get_new_loc(ref);
1071 RefRelocator refer;
1072 ref->metaspace_pointers_do_at(&refer, new_loc);
1073 }
1074 };
1075
1076 // Relocate a reference to point to its shallow copy
1077 class RefRelocator: public MetaspaceClosure {
1078 public:
1079 virtual bool do_ref(Ref* ref, bool read_only) {
1080 if (ref->not_null()) {
1081 ref->update(get_new_loc(ref));
1082 }
1083 return false; // Do not recurse.
1084 }
1085 };
1086
1087 #ifdef ASSERT
1088 class IsRefInArchiveChecker: public MetaspaceClosure {
1089 public:
1090 virtual bool do_ref(Ref* ref, bool read_only) {
1091 if (ref->not_null()) {
1092 char* obj = (char*)ref->obj();
1093 assert(_ro_region.contains(obj) || _rw_region.contains(obj),
1094 "must be relocated to point to CDS archive");
1095 }
1096 return false; // Do not recurse.
1097 }
1098 };
1099 #endif
1100
1101 public:
1102 static void copy_and_compact() {
1103 // We should no longer allocate anything from the metaspace, so that
1104 // we can have a stable set of MetaspaceObjs to work with.
1105 Metaspace::freeze();
1106
1107 ResourceMark rm;
1108 SortedSymbolClosure the_ssc; // StackObj
1109 _ssc = &the_ssc;
1110
1111 tty->print_cr("Scanning all metaspace objects ... ");
1112 {
1113 // allocate and shallow-copy RW objects, immediately following the MC region
1114 tty->print_cr("Allocating RW objects ... ");
1115 _mc_region.pack(&_rw_region);
1116
1117 ResourceMark rm;
1118 ShallowCopier rw_copier(false);
1119 iterate_roots(&rw_copier);
1120 }
1121 {
1122 // allocate and shallow-copy of RO object, immediately following the RW region
1123 tty->print_cr("Allocating RO objects ... ");
1124 _rw_region.pack(&_ro_region);
1125
1126 ResourceMark rm;
1127 ShallowCopier ro_copier(true);
1128 iterate_roots(&ro_copier);
1129 }
1130 {
1131 tty->print_cr("Relocating embedded pointers ... ");
1132 ResourceMark rm;
1133 ShallowCopyEmbeddedRefRelocator emb_reloc;
1134 iterate_roots(&emb_reloc);
1135 }
1136 {
1137 tty->print_cr("Relocating external roots ... ");
1138 ResourceMark rm;
1139 RefRelocator ext_reloc;
1140 iterate_roots(&ext_reloc);
1141 }
1142
1143 #ifdef ASSERT
1144 {
1145 tty->print_cr("Verifying external roots ... ");
1146 ResourceMark rm;
1147 IsRefInArchiveChecker checker;
1148 iterate_roots(&checker);
1149 }
1150 #endif
1151
1152
1153 // cleanup
1154 _ssc = NULL;
1155 }
1156
1157 // We must relocate the System::_well_known_klasses only after we have copied the
1158 // java objects in during dump_java_heap_objects(): during the object copy, we operate on
1159 // old objects which assert that their klass is the original klass.
1160 static void relocate_well_known_klasses() {
1161 {
1162 tty->print_cr("Relocating SystemDictionary::_well_known_klasses[] ... ");
1163 ResourceMark rm;
1164 RefRelocator ext_reloc;
1165 SystemDictionary::well_known_klasses_do(&ext_reloc);
1166 }
1167 // NOTE: after this point, we shouldn't have any globals that can reach the old
1168 // objects.
1169
1170 // We cannot use any of the objects in the heap anymore (except for the objects
1171 // in the CDS shared string regions) because their headers no longer point to
1172 // valid Klasses.
1173 }
1174
1175 static void iterate_roots(MetaspaceClosure* it) {
1176 GrowableArray<Symbol*>* symbols = _ssc->get_sorted_symbols();
1177 for (int i=0; i<symbols->length(); i++) {
1178 it->push(symbols->adr_at(i));
1179 }
1180 if (_global_klass_objects != NULL) {
1181 // Need to fix up the pointers
1182 for (int i = 0; i < _global_klass_objects->length(); i++) {
1183 // NOTE -- this requires that the vtable is NOT yet patched, or else we are hosed.
1184 it->push(_global_klass_objects->adr_at(i));
1185 }
1186 }
1187 FileMapInfo::metaspace_pointers_do(it);
1188 SystemDictionary::classes_do(it);
1189 Universe::metaspace_pointers_do(it);
1190 SymbolTable::metaspace_pointers_do(it);
1191 vmSymbols::metaspace_pointers_do(it);
1192 }
1193
1194 static Klass* get_relocated_klass(Klass* orig_klass) {
1195 address* pp = _new_loc_table->get((address)orig_klass);
1196 assert(pp != NULL, "must be");
1197 Klass* klass = (Klass*)(*pp);
1198 assert(klass->is_klass(), "must be");
1199 return klass;
1200 }
1201 };
1202
1203 DumpAllocStats* ArchiveCompactor::_alloc_stats;
1204 SortedSymbolClosure* ArchiveCompactor::_ssc;
1205 ArchiveCompactor::RelocationTable* ArchiveCompactor::_new_loc_table;
1206
1207 void VM_PopulateDumpSharedSpace::write_region(FileMapInfo* mapinfo, int region_idx,
1208 DumpRegion* dump_region, bool read_only, bool allow_exec) {
1209 mapinfo->write_region(region_idx, dump_region->base(), dump_region->used(), read_only, allow_exec);
1210 }
1211
1212 void VM_PopulateDumpSharedSpace::dump_symbols() {
1213 tty->print_cr("Dumping symbol table ...");
1214
1215 NOT_PRODUCT(SymbolTable::verify());
1216 SymbolTable::write_to_archive();
1217 }
1218
1219 char* VM_PopulateDumpSharedSpace::dump_read_only_tables() {
1220 char* oldtop = _ro_region.top();
1221 // Reorder the system dictionary. Moving the symbols affects
1222 // how the hash table indices are calculated.
1223 SystemDictionary::reorder_dictionary_for_sharing();
1224 tty->print("Removing java_mirror ... ");
1225 remove_java_mirror_in_classes();
1226 tty->print_cr("done. ");
1227 NOT_PRODUCT(SystemDictionary::verify();)
1228
1229 size_t buckets_bytes = SystemDictionary::count_bytes_for_buckets();
1230 char* buckets_top = _ro_region.allocate(buckets_bytes, sizeof(intptr_t));
1231 SystemDictionary::copy_buckets(buckets_top, _ro_region.top());
1232
1233 size_t table_bytes = SystemDictionary::count_bytes_for_table();
1234 char* table_top = _ro_region.allocate(table_bytes, sizeof(intptr_t));
1235 SystemDictionary::copy_table(table_top, _ro_region.top());
1236
1237 // Write the other data to the output array.
1238 WriteClosure wc(&_ro_region);
1239 MetaspaceShared::serialize(&wc);
1240
1241 char* newtop = _ro_region.top();
1242 ArchiveCompactor::alloc_stats()->record_other_type(int(newtop - oldtop), true);
1243 return buckets_top;
1244 }
1245
1246 void VM_PopulateDumpSharedSpace::doit() {
1247 Thread* THREAD = VMThread::vm_thread();
1248
1249 NOT_PRODUCT(SystemDictionary::verify();)
1250 // The following guarantee is meant to ensure that no loader constraints
1251 // exist yet, since the constraints table is not shared. This becomes
1252 // more important now that we don't re-initialize vtables/itables for
1253 // shared classes at runtime, where constraints were previously created.
1254 guarantee(SystemDictionary::constraints()->number_of_entries() == 0,
1255 "loader constraints are not saved");
1256 guarantee(SystemDictionary::placeholders()->number_of_entries() == 0,
1257 "placeholders are not saved");
1258 // Revisit and implement this if we prelink method handle call sites:
1259 guarantee(SystemDictionary::invoke_method_table() == NULL ||
1260 SystemDictionary::invoke_method_table()->number_of_entries() == 0,
1261 "invoke method table is not saved");
1262
1263 // At this point, many classes have been loaded.
1264 // Gather systemDictionary classes in a global array and do everything to
1265 // that so we don't have to walk the SystemDictionary again.
1266 _global_klass_objects = new GrowableArray<Klass*>(1000);
1267 CollectClassesClosure collect_classes;
1268 ClassLoaderDataGraph::loaded_classes_do(&collect_classes);
1269
1270 tty->print_cr("Number of classes %d", _global_klass_objects->length());
1271 {
1272 int num_type_array = 0, num_obj_array = 0, num_inst = 0;
1273 for (int i = 0; i < _global_klass_objects->length(); i++) {
1274 Klass* k = _global_klass_objects->at(i);
1275 if (k->is_instance_klass()) {
1276 num_inst ++;
1277 } else if (k->is_objArray_klass()) {
1278 num_obj_array ++;
1279 } else {
1280 assert(k->is_typeArray_klass(), "sanity");
1281 num_type_array ++;
1282 }
1283 }
1284 tty->print_cr(" instance classes = %5d", num_inst);
1285 tty->print_cr(" obj array classes = %5d", num_obj_array);
1286 tty->print_cr(" type array classes = %5d", num_type_array);
1287 }
1288
1289 // Ensure the ConstMethods won't be modified at run-time
1290 tty->print("Updating ConstMethods ... ");
1291 rewrite_nofast_bytecodes_and_calculate_fingerprints();
1292 tty->print_cr("done. ");
1293
1294 // Move classes from platform/system dictionaries into the boot dictionary
1295 SystemDictionary::combine_shared_dictionaries();
1296
1297 // Remove all references outside the metadata
1298 tty->print("Removing unshareable information ... ");
1299 remove_unshareable_in_classes();
1300 tty->print_cr("done. ");
1301
1302 // We don't support archiving anonymous classes. Verify that they are not stored in
1303 // the any dictionaries.
1304 NOT_PRODUCT(assert_no_anonymoys_classes_in_dictionaries());
1305
1306 SystemDictionaryShared::finalize_verification_constraints();
1307
1308 ArchiveCompactor::initialize();
1309 ArchiveCompactor::copy_and_compact();
1310
1311 dump_symbols();
1312
1313 // Dump supported java heap objects
1314 _string_regions = NULL;
1315 _open_archive_heap_regions = NULL;
1316 dump_java_heap_objects();
1317
1318 ArchiveCompactor::relocate_well_known_klasses();
1319
1320 char* read_only_tables_start = dump_read_only_tables();
1321 _ro_region.pack(&_md_region);
1322
1323 char* vtbl_list = _md_region.top();
1324 MetaspaceShared::allocate_cpp_vtable_clones();
1325 _md_region.pack(&_od_region);
1326
1327 // Relocate the archived class file data into the od region
1328 relocate_cached_class_file();
1329 _od_region.pack();
1330
1331 // The 5 core spaces are allocated consecutively mc->rw->ro->md->od, so there total size
1332 // is just the spaces between the two ends.
1333 size_t core_spaces_size = _od_region.end() - _mc_region.base();
1334 assert(core_spaces_size == (size_t)align_up(core_spaces_size, Metaspace::reserve_alignment()),
1335 "should already be aligned");
1336
1337 // During patching, some virtual methods may be called, so at this point
1338 // the vtables must contain valid methods (as filled in by CppVtableCloner::allocate).
1339 MetaspaceShared::patch_cpp_vtable_pointers();
1340
1341 // The vtable clones contain addresses of the current process.
1342 // We don't want to write these addresses into the archive.
1343 MetaspaceShared::zero_cpp_vtable_clones_for_writing();
1344
1345 // Create and write the archive file that maps the shared spaces.
1346
1347 FileMapInfo* mapinfo = new FileMapInfo();
1348 mapinfo->populate_header(os::vm_allocation_granularity());
1349 mapinfo->set_read_only_tables_start(read_only_tables_start);
1350 mapinfo->set_misc_data_patching_start(vtbl_list);
1351 mapinfo->set_cds_i2i_entry_code_buffers(MetaspaceShared::cds_i2i_entry_code_buffers());
1352 mapinfo->set_cds_i2i_entry_code_buffers_size(MetaspaceShared::cds_i2i_entry_code_buffers_size());
1353 mapinfo->set_core_spaces_size(core_spaces_size);
1354
1355 for (int pass=1; pass<=2; pass++) {
1356 if (pass == 1) {
1357 // The first pass doesn't actually write the data to disk. All it
1358 // does is to update the fields in the mapinfo->_header.
1359 } else {
1360 // After the first pass, the contents of mapinfo->_header are finalized,
1361 // so we can compute the header's CRC, and write the contents of the header
1362 // and the regions into disk.
1363 mapinfo->open_for_write();
1364 mapinfo->set_header_crc(mapinfo->compute_header_crc());
1365 }
1366 mapinfo->write_header();
1367
1368 // NOTE: md contains the trampoline code for method entries, which are patched at run time,
1369 // so it needs to be read/write.
1370 write_region(mapinfo, MetaspaceShared::mc, &_mc_region, /*read_only=*/false,/*allow_exec=*/true);
1371 write_region(mapinfo, MetaspaceShared::rw, &_rw_region, /*read_only=*/false,/*allow_exec=*/false);
1372 write_region(mapinfo, MetaspaceShared::ro, &_ro_region, /*read_only=*/true, /*allow_exec=*/false);
1373 write_region(mapinfo, MetaspaceShared::md, &_md_region, /*read_only=*/false,/*allow_exec=*/false);
1374 write_region(mapinfo, MetaspaceShared::od, &_od_region, /*read_only=*/true, /*allow_exec=*/false);
1375
1376 _total_string_region_size = mapinfo->write_archive_heap_regions(
1377 _string_regions,
1378 MetaspaceShared::first_string,
1379 MetaspaceShared::max_strings);
1380 _total_open_archive_region_size = mapinfo->write_archive_heap_regions(
1381 _open_archive_heap_regions,
1382 MetaspaceShared::first_open_archive_heap_region,
1383 MetaspaceShared::max_open_archive_heap_region);
1384 }
1385
1386 mapinfo->close();
1387
1388 // Restore the vtable in case we invoke any virtual methods.
1389 MetaspaceShared::clone_cpp_vtables((intptr_t*)vtbl_list);
1390
1391 print_region_stats();
1392
1393 if (log_is_enabled(Info, cds)) {
1394 ArchiveCompactor::alloc_stats()->print_stats(int(_ro_region.used()), int(_rw_region.used()),
1395 int(_mc_region.used()), int(_md_region.used()));
1396 }
1397
1398 if (PrintSystemDictionaryAtExit) {
1399 SystemDictionary::print();
1400 }
1401 // There may be other pending VM operations that operate on the InstanceKlasses,
1402 // which will fail because InstanceKlasses::remove_unshareable_info()
1403 // has been called. Forget these operations and exit the VM directly.
1404 vm_direct_exit(0);
1405 }
1406
1407 void VM_PopulateDumpSharedSpace::print_region_stats() {
1408 // Print statistics of all the regions
1409 const size_t total_reserved = _ro_region.reserved() + _rw_region.reserved() +
1410 _mc_region.reserved() + _md_region.reserved() +
1411 _od_region.reserved() +
1412 _total_string_region_size +
1413 _total_open_archive_region_size;
1414 const size_t total_bytes = _ro_region.used() + _rw_region.used() +
1415 _mc_region.used() + _md_region.used() +
1416 _od_region.used() +
1417 _total_string_region_size +
1418 _total_open_archive_region_size;
1419 const double total_u_perc = percent_of(total_bytes, total_reserved);
1420
1421 _mc_region.print(total_reserved);
1422 _rw_region.print(total_reserved);
1423 _ro_region.print(total_reserved);
1424 _md_region.print(total_reserved);
1425 _od_region.print(total_reserved);
1426 print_heap_region_stats(_string_regions, "st", total_reserved);
1427 print_heap_region_stats(_open_archive_heap_regions, "oa", total_reserved);
1428
1429 tty->print_cr("total : " SIZE_FORMAT_W(9) " [100.0%% of total] out of " SIZE_FORMAT_W(9) " bytes [%5.1f%% used]",
1430 total_bytes, total_reserved, total_u_perc);
1431 }
1432
1433 void VM_PopulateDumpSharedSpace::print_heap_region_stats(GrowableArray<MemRegion> *heap_mem,
1434 const char *name, const size_t total_size) {
1435 int arr_len = heap_mem == NULL ? 0 : heap_mem->length();
1436 for (int i = 0; i < arr_len; i++) {
1437 char* start = (char*)heap_mem->at(i).start();
1438 size_t size = heap_mem->at(i).byte_size();
1439 char* top = start + size;
1440 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,
1441 name, i, size, size/double(total_size)*100.0, size, p2i(start));
1442
1443 }
1444 }
1445
1446 // Update a Java object to point its Klass* to the new location after
1447 // shared archive has been compacted.
1448 void MetaspaceShared::relocate_klass_ptr(oop o) {
1449 assert(DumpSharedSpaces, "sanity");
1450 Klass* k = ArchiveCompactor::get_relocated_klass(o->klass());
1451 o->set_klass(k);
1452 }
1453
1454 class LinkSharedClassesClosure : public KlassClosure {
1455 Thread* THREAD;
1456 bool _made_progress;
1457 public:
1458 LinkSharedClassesClosure(Thread* thread) : THREAD(thread), _made_progress(false) {}
1459
1460 void reset() { _made_progress = false; }
1461 bool made_progress() const { return _made_progress; }
1462
1463 void do_klass(Klass* k) {
1464 if (k->is_instance_klass()) {
1465 InstanceKlass* ik = InstanceKlass::cast(k);
1466 // Link the class to cause the bytecodes to be rewritten and the
1467 // cpcache to be created. Class verification is done according
1468 // to -Xverify setting.
1469 _made_progress |= MetaspaceShared::try_link_class(ik, THREAD);
1470 guarantee(!HAS_PENDING_EXCEPTION, "exception in link_class");
1471
1472 ik->constants()->resolve_class_constants(THREAD);
1473 }
1474 }
1475 };
1476
1477 class CheckSharedClassesClosure : public KlassClosure {
1478 bool _made_progress;
1479 public:
1480 CheckSharedClassesClosure() : _made_progress(false) {}
1481
1482 void reset() { _made_progress = false; }
1483 bool made_progress() const { return _made_progress; }
1484 void do_klass(Klass* k) {
1485 if (k->is_instance_klass() && InstanceKlass::cast(k)->check_sharing_error_state()) {
1486 _made_progress = true;
1487 }
1488 }
1489 };
1490
1491 void MetaspaceShared::check_shared_class_loader_type(Klass* k) {
1492 if (k->is_instance_klass()) {
1493 InstanceKlass* ik = InstanceKlass::cast(k);
1494 u2 loader_type = ik->loader_type();
1495 ResourceMark rm;
1496 guarantee(loader_type != 0,
1497 "Class loader type is not set for this class %s", ik->name()->as_C_string());
1498 }
1499 }
1500
1501 void MetaspaceShared::link_and_cleanup_shared_classes(TRAPS) {
1502 // We need to iterate because verification may cause additional classes
1503 // to be loaded.
1504 LinkSharedClassesClosure link_closure(THREAD);
1505 do {
1506 link_closure.reset();
1507 ClassLoaderDataGraph::loaded_classes_do(&link_closure);
1508 guarantee(!HAS_PENDING_EXCEPTION, "exception in link_class");
1509 } while (link_closure.made_progress());
1510
1511 if (_has_error_classes) {
1512 // Mark all classes whose super class or interfaces failed verification.
1513 CheckSharedClassesClosure check_closure;
1514 do {
1515 // Not completely sure if we need to do this iteratively. Anyway,
1516 // we should come here only if there are unverifiable classes, which
1517 // shouldn't happen in normal cases. So better safe than sorry.
1518 check_closure.reset();
1519 ClassLoaderDataGraph::loaded_classes_do(&check_closure);
1520 } while (check_closure.made_progress());
1521
1522 if (IgnoreUnverifiableClassesDuringDump) {
1523 // This is useful when running JCK or SQE tests. You should not
1524 // enable this when running real apps.
1525 SystemDictionary::remove_classes_in_error_state();
1526 } else {
1527 tty->print_cr("Please remove the unverifiable classes from your class list and try again");
1528 exit(1);
1529 }
1530 }
1531 }
1532
1533 void MetaspaceShared::prepare_for_dumping() {
1534 Arguments::check_unsupported_dumping_properties();
1535 ClassLoader::initialize_shared_path();
1536 FileMapInfo::allocate_classpath_entry_table();
1537 }
1538
1539 // Preload classes from a list, populate the shared spaces and dump to a
1540 // file.
1541 void MetaspaceShared::preload_and_dump(TRAPS) {
1542 { TraceTime timer("Dump Shared Spaces", TRACETIME_LOG(Info, startuptime));
1543 ResourceMark rm;
1544 char class_list_path_str[JVM_MAXPATHLEN];
1545 // Preload classes to be shared.
1546 // Should use some os:: method rather than fopen() here. aB.
1547 const char* class_list_path;
1548 if (SharedClassListFile == NULL) {
1549 // Construct the path to the class list (in jre/lib)
1550 // Walk up two directories from the location of the VM and
1551 // optionally tack on "lib" (depending on platform)
1552 os::jvm_path(class_list_path_str, sizeof(class_list_path_str));
1553 for (int i = 0; i < 3; i++) {
1554 char *end = strrchr(class_list_path_str, *os::file_separator());
1555 if (end != NULL) *end = '\0';
1556 }
1557 int class_list_path_len = (int)strlen(class_list_path_str);
1558 if (class_list_path_len >= 3) {
1559 if (strcmp(class_list_path_str + class_list_path_len - 3, "lib") != 0) {
1560 if (class_list_path_len < JVM_MAXPATHLEN - 4) {
1561 jio_snprintf(class_list_path_str + class_list_path_len,
1562 sizeof(class_list_path_str) - class_list_path_len,
1563 "%slib", os::file_separator());
1564 class_list_path_len += 4;
1565 }
1566 }
1567 }
1568 if (class_list_path_len < JVM_MAXPATHLEN - 10) {
1569 jio_snprintf(class_list_path_str + class_list_path_len,
1570 sizeof(class_list_path_str) - class_list_path_len,
1571 "%sclasslist", os::file_separator());
1572 }
1573 class_list_path = class_list_path_str;
1574 } else {
1575 class_list_path = SharedClassListFile;
1576 }
1577
1578 tty->print_cr("Loading classes to share ...");
1579 _has_error_classes = false;
1580 int class_count = preload_classes(class_list_path, THREAD);
1581 if (ExtraSharedClassListFile) {
1582 class_count += preload_classes(ExtraSharedClassListFile, THREAD);
1583 }
1584 tty->print_cr("Loading classes to share: done.");
1585
1586 log_info(cds)("Shared spaces: preloaded %d classes", class_count);
1587
1588 // Rewrite and link classes
1589 tty->print_cr("Rewriting and linking classes ...");
1590
1591 // Link any classes which got missed. This would happen if we have loaded classes that
1592 // were not explicitly specified in the classlist. E.g., if an interface implemented by class K
1593 // fails verification, all other interfaces that were not specified in the classlist but
1594 // are implemented by K are not verified.
1595 link_and_cleanup_shared_classes(CATCH);
1596 tty->print_cr("Rewriting and linking classes: done");
1597
1598 SystemDictionary::clear_invoke_method_table();
1599
1600 VM_PopulateDumpSharedSpace op;
1601 VMThread::execute(&op);
1602 }
1603 }
1604
1605
1606 int MetaspaceShared::preload_classes(const char* class_list_path, TRAPS) {
1607 ClassListParser parser(class_list_path);
1608 int class_count = 0;
1609
1610 while (parser.parse_one_line()) {
1611 Klass* klass = ClassLoaderExt::load_one_class(&parser, THREAD);
1612 if (HAS_PENDING_EXCEPTION) {
1613 if (klass == NULL &&
1614 (PENDING_EXCEPTION->klass()->name() == vmSymbols::java_lang_ClassNotFoundException())) {
1615 // print a warning only when the pending exception is class not found
1616 tty->print_cr("Preload Warning: Cannot find %s", parser.current_class_name());
1617 }
1618 CLEAR_PENDING_EXCEPTION;
1619 }
1620 if (klass != NULL) {
1621 if (log_is_enabled(Trace, cds)) {
1622 ResourceMark rm;
1623 log_trace(cds)("Shared spaces preloaded: %s", klass->external_name());
1624 }
1625
1626 if (klass->is_instance_klass()) {
1627 InstanceKlass* ik = InstanceKlass::cast(klass);
1628
1629 // Link the class to cause the bytecodes to be rewritten and the
1630 // cpcache to be created. The linking is done as soon as classes
1631 // are loaded in order that the related data structures (klass and
1632 // cpCache) are located together.
1633 try_link_class(ik, THREAD);
1634 guarantee(!HAS_PENDING_EXCEPTION, "exception in link_class");
1635 }
1636
1637 class_count++;
1638 }
1639 }
1640
1641 return class_count;
1642 }
1643
1644 // Returns true if the class's status has changed
1645 bool MetaspaceShared::try_link_class(InstanceKlass* ik, TRAPS) {
1646 assert(DumpSharedSpaces, "should only be called during dumping");
1647 if (ik->init_state() < InstanceKlass::linked) {
1648 bool saved = BytecodeVerificationLocal;
1649 if (!(ik->is_shared_boot_class())) {
1650 // The verification decision is based on BytecodeVerificationRemote
1651 // for non-system classes. Since we are using the NULL classloader
1652 // to load non-system classes during dumping, we need to temporarily
1653 // change BytecodeVerificationLocal to be the same as
1654 // BytecodeVerificationRemote. Note this can cause the parent system
1655 // classes also being verified. The extra overhead is acceptable during
1656 // dumping.
1657 BytecodeVerificationLocal = BytecodeVerificationRemote;
1658 }
1659 ik->link_class(THREAD);
1660 if (HAS_PENDING_EXCEPTION) {
1661 ResourceMark rm;
1662 tty->print_cr("Preload Warning: Verification failed for %s",
1663 ik->external_name());
1664 CLEAR_PENDING_EXCEPTION;
1665 ik->set_in_error_state();
1666 _has_error_classes = true;
1667 }
1668 BytecodeVerificationLocal = saved;
1669 return true;
1670 } else {
1671 return false;
1672 }
1673 }
1674
1675 #if INCLUDE_CDS_JAVA_HEAP
1676 void VM_PopulateDumpSharedSpace::dump_java_heap_objects() {
1677 if (!MetaspaceShared::is_heap_object_archiving_allowed()) {
1678 if (log_is_enabled(Info, cds)) {
1679 log_info(cds)(
1680 "Archived java heap is not supported as UseG1GC, "
1681 "UseCompressedOops and UseCompressedClassPointers are required."
1682 "Current settings: UseG1GC=%s, UseCompressedOops=%s, UseCompressedClassPointers=%s.",
1683 BOOL_TO_STR(UseG1GC), BOOL_TO_STR(UseCompressedOops),
1684 BOOL_TO_STR(UseCompressedClassPointers));
1685 }
1686 return;
1687 }
1688
1689 {
1690 NoSafepointVerifier nsv;
1691
1692 // Cache for recording where the archived objects are copied to
1693 MetaspaceShared::create_archive_object_cache();
1694
1695 tty->print_cr("Dumping String objects to closed archive heap region ...");
1696 NOT_PRODUCT(StringTable::verify());
1697 // The string space has maximum two regions. See FileMapInfo::write_archive_heap_regions() for details.
1698 _string_regions = new GrowableArray<MemRegion>(2);
1699 StringTable::write_to_archive(_string_regions);
1700
1701 tty->print_cr("Dumping objects to open archive heap region ...");
1702 _open_archive_heap_regions = new GrowableArray<MemRegion>(2);
1703 MetaspaceShared::dump_open_archive_heap_objects(_open_archive_heap_regions);
1704
1705 MetaspaceShared::destroy_archive_object_cache();
1706 }
1707
1708 G1HeapVerifier::verify_archive_regions();
1709 }
1710
1711 void MetaspaceShared::dump_open_archive_heap_objects(
1712 GrowableArray<MemRegion> * open_archive) {
1713 assert(UseG1GC, "Only support G1 GC");
1714 assert(UseCompressedOops && UseCompressedClassPointers,
1715 "Only support UseCompressedOops and UseCompressedClassPointers enabled");
1716
1717 Thread* THREAD = Thread::current();
1718 G1CollectedHeap::heap()->begin_archive_alloc_range(true /* open */);
1719
1720 MetaspaceShared::archive_resolved_constants(THREAD);
1721
1722 G1CollectedHeap::heap()->end_archive_alloc_range(open_archive,
1723 os::vm_allocation_granularity());
1724 }
1725
1726 MetaspaceShared::ArchivedObjectCache* MetaspaceShared::_archive_object_cache = NULL;
1727 oop MetaspaceShared::archive_heap_object(oop obj, Thread* THREAD) {
1728 assert(DumpSharedSpaces, "dump-time only");
1729
1730 ArchivedObjectCache* cache = MetaspaceShared::archive_object_cache();
1731 oop* p = cache->get(obj);
1732 if (p != NULL) {
1733 // already archived
1734 return *p;
1735 }
1736
1737 int len = obj->size();
1738 if (G1CollectedHeap::heap()->is_archive_alloc_too_large(len)) {
1739 return NULL;
1740 }
1741
1742 int hash = obj->identity_hash();
1743 oop archived_oop = (oop)G1CollectedHeap::heap()->archive_mem_allocate(len);
1744 if (archived_oop != NULL) {
1745 Copy::aligned_disjoint_words((HeapWord*)obj, (HeapWord*)archived_oop, len);
1746 relocate_klass_ptr(archived_oop);
1747 cache->put(obj, archived_oop);
1748 }
1749 return archived_oop;
1750 }
1751
1752 void MetaspaceShared::archive_resolved_constants(Thread* THREAD) {
1753 int i;
1754 for (i = 0; i < _global_klass_objects->length(); i++) {
1755 Klass* k = _global_klass_objects->at(i);
1756 if (k->is_instance_klass()) {
1757 InstanceKlass* ik = InstanceKlass::cast(k);
1758 ik->constants()->archive_resolved_references(THREAD);
1759 }
1760 }
1761 }
1762
1763 void MetaspaceShared::fixup_mapped_heap_regions() {
1764 FileMapInfo *mapinfo = FileMapInfo::current_info();
1765 mapinfo->fixup_mapped_heap_regions();
1766 }
1767 #endif // INCLUDE_CDS_JAVA_HEAP
1768
1769 // Closure for serializing initialization data in from a data area
1770 // (ptr_array) read from the shared file.
1771
1772 class ReadClosure : public SerializeClosure {
1773 private:
1774 intptr_t** _ptr_array;
1775
1776 inline intptr_t nextPtr() {
1777 return *(*_ptr_array)++;
1778 }
1779
1780 public:
1781 ReadClosure(intptr_t** ptr_array) { _ptr_array = ptr_array; }
1782
1783 void do_ptr(void** p) {
1784 assert(*p == NULL, "initializing previous initialized pointer.");
1785 intptr_t obj = nextPtr();
1786 assert((intptr_t)obj >= 0 || (intptr_t)obj < -100,
1787 "hit tag while initializing ptrs.");
1788 *p = (void*)obj;
1789 }
1790
1791 void do_u4(u4* p) {
1792 intptr_t obj = nextPtr();
1793 *p = (u4)(uintx(obj));
1794 }
1795
1796 void do_tag(int tag) {
1797 int old_tag;
1798 old_tag = (int)(intptr_t)nextPtr();
1799 // do_int(&old_tag);
1800 assert(tag == old_tag, "old tag doesn't match");
1801 FileMapInfo::assert_mark(tag == old_tag);
1802 }
1803
1804 void do_region(u_char* start, size_t size) {
1805 assert((intptr_t)start % sizeof(intptr_t) == 0, "bad alignment");
1806 assert(size % sizeof(intptr_t) == 0, "bad size");
1807 do_tag((int)size);
1808 while (size > 0) {
1809 *(intptr_t*)start = nextPtr();
1810 start += sizeof(intptr_t);
1811 size -= sizeof(intptr_t);
1812 }
1813 }
1814
1815 bool reading() const { return true; }
1816 };
1817
1818 // Return true if given address is in the misc data region
1819 bool MetaspaceShared::is_in_shared_region(const void* p, int idx) {
1820 return UseSharedSpaces && FileMapInfo::current_info()->is_in_shared_region(p, idx);
1821 }
1822
1823 bool MetaspaceShared::is_in_trampoline_frame(address addr) {
1824 if (UseSharedSpaces && is_in_shared_region(addr, MetaspaceShared::mc)) {
1825 return true;
1826 }
1827 return false;
1828 }
1829
1830 void MetaspaceShared::print_shared_spaces() {
1831 if (UseSharedSpaces) {
1832 FileMapInfo::current_info()->print_shared_spaces();
1833 }
1834 }
1835
1836
1837 // Map shared spaces at requested addresses and return if succeeded.
1838 bool MetaspaceShared::map_shared_spaces(FileMapInfo* mapinfo) {
1839 size_t image_alignment = mapinfo->alignment();
1840
1841 #ifndef _WINDOWS
1842 // Map in the shared memory and then map the regions on top of it.
1843 // On Windows, don't map the memory here because it will cause the
1844 // mappings of the regions to fail.
1845 ReservedSpace shared_rs = mapinfo->reserve_shared_memory();
1846 if (!shared_rs.is_reserved()) return false;
1847 #endif
1848
1849 assert(!DumpSharedSpaces, "Should not be called with DumpSharedSpaces");
1850
1851 char* ro_base = NULL; char* ro_top;
1852 char* rw_base = NULL; char* rw_top;
1853 char* mc_base = NULL; char* mc_top;
1854 char* md_base = NULL; char* md_top;
1855 char* od_base = NULL; char* od_top;
1856
1857 // Map each shared region
1858 if ((mc_base = mapinfo->map_region(mc, &mc_top)) != NULL &&
1859 (rw_base = mapinfo->map_region(rw, &rw_top)) != NULL &&
1860 (ro_base = mapinfo->map_region(ro, &ro_top)) != NULL &&
1861 (md_base = mapinfo->map_region(md, &md_top)) != NULL &&
1862 (od_base = mapinfo->map_region(od, &od_top)) != NULL &&
1863 (image_alignment == (size_t)os::vm_allocation_granularity()) &&
1864 mapinfo->validate_classpath_entry_table()) {
1865 // Success -- set up MetaspaceObj::_shared_metaspace_{base,top} for
1866 // fast checking in MetaspaceShared::is_in_shared_metaspace() and
1867 // MetaspaceObj::is_shared().
1868 //
1869 // We require that mc->rw->ro->md->od to be laid out consecutively, with no
1870 // gaps between them. That way, we can ensure that the OS won't be able to
1871 // allocate any new memory spaces inside _shared_metaspace_{base,top}, which
1872 // would mess up the simple comparision in MetaspaceShared::is_in_shared_metaspace().
1873 assert(mc_base < ro_base && mc_base < rw_base && mc_base < md_base && mc_base < od_base, "must be");
1874 assert(od_top > ro_top && od_top > rw_top && od_top > md_top && od_top > mc_top , "must be");
1875 assert(mc_top == rw_base, "must be");
1876 assert(rw_top == ro_base, "must be");
1877 assert(ro_top == md_base, "must be");
1878 assert(md_top == od_base, "must be");
1879
1880 MetaspaceObj::_shared_metaspace_base = (void*)mc_base;
1881 MetaspaceObj::_shared_metaspace_top = (void*)od_top;
1882 return true;
1883 } else {
1884 // If there was a failure in mapping any of the spaces, unmap the ones
1885 // that succeeded
1886 if (ro_base != NULL) mapinfo->unmap_region(ro);
1887 if (rw_base != NULL) mapinfo->unmap_region(rw);
1888 if (mc_base != NULL) mapinfo->unmap_region(mc);
1889 if (md_base != NULL) mapinfo->unmap_region(md);
1890 if (od_base != NULL) mapinfo->unmap_region(od);
1891 #ifndef _WINDOWS
1892 // Release the entire mapped region
1893 shared_rs.release();
1894 #endif
1895 // If -Xshare:on is specified, print out the error message and exit VM,
1896 // otherwise, set UseSharedSpaces to false and continue.
1897 if (RequireSharedSpaces || PrintSharedArchiveAndExit) {
1898 vm_exit_during_initialization("Unable to use shared archive.", "Failed map_region for using -Xshare:on.");
1899 } else {
1900 FLAG_SET_DEFAULT(UseSharedSpaces, false);
1901 }
1902 return false;
1903 }
1904 }
1905
1906 // Read the miscellaneous data from the shared file, and
1907 // serialize it out to its various destinations.
1908
1909 void MetaspaceShared::initialize_shared_spaces() {
1910 FileMapInfo *mapinfo = FileMapInfo::current_info();
1911 _cds_i2i_entry_code_buffers = mapinfo->cds_i2i_entry_code_buffers();
1912 _cds_i2i_entry_code_buffers_size = mapinfo->cds_i2i_entry_code_buffers_size();
1913 _core_spaces_size = mapinfo->core_spaces_size();
1914 char* buffer = mapinfo->misc_data_patching_start();
1915 clone_cpp_vtables((intptr_t*)buffer);
1916
1917 // The rest of the data is now stored in the RW region
1918 buffer = mapinfo->read_only_tables_start();
1919 int sharedDictionaryLen = *(intptr_t*)buffer;
1920 buffer += sizeof(intptr_t);
1921 int number_of_entries = *(intptr_t*)buffer;
1922 buffer += sizeof(intptr_t);
1923 SystemDictionary::set_shared_dictionary((HashtableBucket<mtClass>*)buffer,
1924 sharedDictionaryLen,
1925 number_of_entries);
1926 buffer += sharedDictionaryLen;
1927
1928 // The following data are the linked list elements
1929 // (HashtableEntry objects) for the shared dictionary table.
1930
1931 int len = *(intptr_t*)buffer; // skip over shared dictionary entries
1932 buffer += sizeof(intptr_t);
1933 buffer += len;
1934
1935 // Verify various attributes of the archive, plus initialize the
1936 // shared string/symbol tables
1937 intptr_t* array = (intptr_t*)buffer;
1938 ReadClosure rc(&array);
1939 serialize(&rc);
1940
1941 // Initialize the run-time symbol table.
1942 SymbolTable::create_table();
1943
1944 // Close the mapinfo file
1945 mapinfo->close();
1946
1947 if (PrintSharedArchiveAndExit) {
1948 if (PrintSharedDictionary) {
1949 tty->print_cr("\nShared classes:\n");
1950 SystemDictionary::print_shared(tty);
1951 }
1952 if (_archive_loading_failed) {
1953 tty->print_cr("archive is invalid");
1954 vm_exit(1);
1955 } else {
1956 tty->print_cr("archive is valid");
1957 vm_exit(0);
1958 }
1959 }
1960 }
1961
1962 // JVM/TI RedefineClasses() support:
1963 bool MetaspaceShared::remap_shared_readonly_as_readwrite() {
1964 assert(SafepointSynchronize::is_at_safepoint(), "must be at safepoint");
1965
1966 if (UseSharedSpaces) {
1967 // remap the shared readonly space to shared readwrite, private
1968 FileMapInfo* mapinfo = FileMapInfo::current_info();
1969 if (!mapinfo->remap_shared_readonly_as_readwrite()) {
1970 return false;
1971 }
1972 _remapped_readwrite = true;
1973 }
1974 return true;
1975 }
1976
1977 void MetaspaceShared::report_out_of_space(const char* name, size_t needed_bytes) {
1978 // This is highly unlikely to happen on 64-bits because we have reserved a 4GB space.
1979 // On 32-bit we reserve only 256MB so you could run out of space with 100,000 classes
1980 // or so.
1981 _mc_region.print_out_of_space_msg(name, needed_bytes);
1982 _rw_region.print_out_of_space_msg(name, needed_bytes);
1983 _ro_region.print_out_of_space_msg(name, needed_bytes);
1984 _md_region.print_out_of_space_msg(name, needed_bytes);
1985 _od_region.print_out_of_space_msg(name, needed_bytes);
1986
1987 vm_exit_during_initialization(err_msg("Unable to allocate from '%s' region", name),
1988 "Please reduce the number of shared classes.");
1989 }