1 /*
2 * Copyright (c) 2019, 2020, 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/classLoaderData.inline.hpp"
28 #include "classfile/symbolTable.hpp"
29 #include "classfile/systemDictionary.hpp"
30 #include "classfile/systemDictionaryShared.hpp"
31 #include "logging/log.hpp"
32 #include "memory/archiveUtils.inline.hpp"
33 #include "memory/dynamicArchive.hpp"
34 #include "memory/metadataFactory.hpp"
35 #include "memory/metaspace.hpp"
36 #include "memory/metaspaceClosure.hpp"
37 #include "memory/metaspaceShared.hpp"
38 #include "memory/resourceArea.hpp"
39 #include "oops/compressedOops.hpp"
40 #include "oops/objArrayKlass.hpp"
41 #include "prims/jvmtiRedefineClasses.hpp"
42 #include "runtime/handles.inline.hpp"
43 #include "runtime/os.inline.hpp"
44 #include "runtime/sharedRuntime.hpp"
45 #include "runtime/vmThread.hpp"
46 #include "runtime/vmOperations.hpp"
47 #include "utilities/bitMap.inline.hpp"
48
49 #ifndef O_BINARY // if defined (Win32) use binary files.
50 #define O_BINARY 0 // otherwise do nothing.
51 #endif
52
53 class DynamicArchiveBuilder : ResourceObj {
54 static unsigned my_hash(const address& a) {
55 return primitive_hash<address>(a);
56 }
57 static bool my_equals(const address& a0, const address& a1) {
58 return primitive_equals<address>(a0, a1);
59 }
60 typedef ResourceHashtable<
61 address, address,
62 DynamicArchiveBuilder::my_hash, // solaris compiler doesn't like: primitive_hash<address>
63 DynamicArchiveBuilder::my_equals, // solaris compiler doesn't like: primitive_equals<address>
64 16384, ResourceObj::C_HEAP> RelocationTable;
65 RelocationTable _new_loc_table;
66
67 static intx _buffer_to_target_delta;
68
69 DumpRegion* _current_dump_space;
70
71 static size_t reserve_alignment() {
72 return Metaspace::reserve_alignment();
73 }
74
75 static const int _total_dump_regions = 3;
76 int _num_dump_regions_used;
77
78 public:
79 void mark_pointer(address* ptr_loc) {
80 ArchivePtrMarker::mark_pointer(ptr_loc);
81 }
82
83 DumpRegion* current_dump_space() const {
84 return _current_dump_space;
85 }
86
87 bool is_in_buffer_space(address p) const {
88 return (_alloc_bottom <= p && p < (address)current_dump_space()->top());
89 }
90
91 template <typename T> bool is_in_target_space(T target_obj) const {
92 address buff_obj = address(target_obj) - _buffer_to_target_delta;
93 return is_in_buffer_space(buff_obj);
94 }
95
96 template <typename T> bool is_in_buffer_space(T obj) const {
97 return is_in_buffer_space(address(obj));
98 }
99
100 template <typename T> T to_target_no_check(T obj) const {
101 return (T)(address(obj) + _buffer_to_target_delta);
102 }
103
104 template <typename T> T to_target(T obj) const {
105 assert(is_in_buffer_space(obj), "must be");
106 return (T)(address(obj) + _buffer_to_target_delta);
107 }
108
109 template <typename T> T get_new_loc(T obj) {
110 address* pp = _new_loc_table.get((address)obj);
111 if (pp == NULL) {
112 // Excluded klasses are not copied
113 return NULL;
114 } else {
115 return (T)*pp;
116 }
117 }
118
119 address get_new_loc(MetaspaceClosure::Ref* ref) {
120 return get_new_loc(ref->obj());
121 }
122
123 template <typename T> bool has_new_loc(T obj) {
124 address* pp = _new_loc_table.get((address)obj);
125 return pp != NULL;
126 }
127
128 static int dynamic_dump_method_comparator(Method* a, Method* b) {
129 Symbol* a_name = a->name();
130 Symbol* b_name = b->name();
131
132 if (a_name == b_name) {
133 return 0;
134 }
135
136 if (!MetaspaceShared::is_in_shared_metaspace(a_name)) {
137 // a_name points to a Symbol in the top archive.
138 // When this method is called, a_name is still pointing to the output space.
139 // Translate it to point to the output space, so that it can be compared with
140 // Symbols in the base archive.
141 a_name = (Symbol*)(address(a_name) + _buffer_to_target_delta);
142 }
143 if (!MetaspaceShared::is_in_shared_metaspace(b_name)) {
144 b_name = (Symbol*)(address(b_name) + _buffer_to_target_delta);
145 }
146
147 return a_name->fast_compare(b_name);
148 }
149
150 protected:
151 enum FollowMode {
152 make_a_copy, point_to_it, set_to_null
153 };
154
155 public:
156 void copy(MetaspaceClosure::Ref* ref, bool read_only) {
157 int bytes = ref->size() * BytesPerWord;
158 address old_obj = ref->obj();
159 address new_obj = copy_impl(ref, read_only, bytes);
160
161 assert(new_obj != NULL, "must be");
162 assert(new_obj != old_obj, "must be");
163 bool isnew = _new_loc_table.put(old_obj, new_obj);
164 assert(isnew, "must be");
165 }
166
167 // Make a shallow copy of each eligible MetaspaceObj into the buffer.
168 class ShallowCopier: public UniqueMetaspaceClosure {
169 DynamicArchiveBuilder* _builder;
170 bool _read_only;
171 public:
172 ShallowCopier(DynamicArchiveBuilder* shuffler, bool read_only)
173 : _builder(shuffler), _read_only(read_only) {}
174
175 virtual bool do_unique_ref(Ref* orig_obj, bool read_only) {
176 // This method gets called on each *original* object
177 // reachable from _builder->iterate_roots(). Each orig_obj is
178 // called exactly once.
179 FollowMode mode = _builder->follow_ref(orig_obj);
180
181 if (mode == point_to_it) {
182 if (read_only == _read_only) {
183 log_debug(cds, dynamic)("ptr : " PTR_FORMAT " %s", p2i(orig_obj->obj()),
184 MetaspaceObj::type_name(orig_obj->msotype()));
185 address p = orig_obj->obj();
186 bool isnew = _builder->_new_loc_table.put(p, p);
187 assert(isnew, "must be");
188 }
189 return false;
190 }
191
192 if (mode == set_to_null) {
193 log_debug(cds, dynamic)("nul : " PTR_FORMAT " %s", p2i(orig_obj->obj()),
194 MetaspaceObj::type_name(orig_obj->msotype()));
195 return false;
196 }
197
198 if (read_only == _read_only) {
199 // Make a shallow copy of orig_obj in a buffer (maintained
200 // by copy_impl in a subclass of DynamicArchiveBuilder).
201 _builder->copy(orig_obj, read_only);
202 }
203 return true;
204 }
205 };
206
207 // Relocate all embedded pointer fields within a MetaspaceObj's shallow copy
208 class ShallowCopyEmbeddedRefRelocator: public UniqueMetaspaceClosure {
209 DynamicArchiveBuilder* _builder;
210 public:
211 ShallowCopyEmbeddedRefRelocator(DynamicArchiveBuilder* shuffler)
212 : _builder(shuffler) {}
213
214 // This method gets called on each *original* object reachable
215 // from _builder->iterate_roots(). Each orig_obj is
216 // called exactly once.
217 virtual bool do_unique_ref(Ref* orig_ref, bool read_only) {
218 FollowMode mode = _builder->follow_ref(orig_ref);
219
220 if (mode == point_to_it) {
221 // We did not make a copy of this object
222 // and we have nothing to update
223 assert(_builder->get_new_loc(orig_ref) == NULL ||
224 _builder->get_new_loc(orig_ref) == orig_ref->obj(), "must be");
225 return false;
226 }
227
228 if (mode == set_to_null) {
229 // We did not make a copy of this object
230 // and we have nothing to update
231 assert(!_builder->has_new_loc(orig_ref->obj()), "must not be copied or pointed to");
232 return false;
233 }
234
235 // - orig_obj points to the original object.
236 // - new_obj points to the shallow copy (created by ShallowCopier)
237 // of orig_obj. new_obj is NULL if the orig_obj is excluded
238 address orig_obj = orig_ref->obj();
239 address new_obj = _builder->get_new_loc(orig_ref);
240
241 assert(new_obj != orig_obj, "must be");
242 #ifdef ASSERT
243 if (new_obj == NULL) {
244 if (orig_ref->msotype() == MetaspaceObj::ClassType) {
245 Klass* k = (Klass*)orig_obj;
246 assert(k->is_instance_klass() &&
247 SystemDictionaryShared::is_excluded_class(InstanceKlass::cast(k)),
248 "orig_obj must be excluded Class");
249 }
250 }
251 #endif
252
253 log_debug(cds, dynamic)("Relocating " PTR_FORMAT " %s", p2i(new_obj),
254 MetaspaceObj::type_name(orig_ref->msotype()));
255 if (new_obj != NULL) {
256 EmbeddedRefUpdater updater(_builder, orig_obj, new_obj);
257 orig_ref->metaspace_pointers_do(&updater);
258 }
259
260 return true; // keep recursing until every object is visited exactly once.
261 }
262
263 virtual void push_special(SpecialRef type, Ref* ref, intptr_t* p) {
264 assert(type == _method_entry_ref, "only special type allowed for now");
265 address obj = ref->obj();
266 address new_obj = _builder->get_new_loc(ref);
267 size_t offset = pointer_delta(p, obj, sizeof(u1));
268 intptr_t* new_p = (intptr_t*)(new_obj + offset);
269 assert(*p == *new_p, "must be a copy");
270 ArchivePtrMarker::mark_pointer((address*)new_p);
271 }
272 };
273
274 class EmbeddedRefUpdater: public MetaspaceClosure {
275 DynamicArchiveBuilder* _builder;
276 address _orig_obj;
277 address _new_obj;
278 public:
279 EmbeddedRefUpdater(DynamicArchiveBuilder* shuffler, address orig_obj, address new_obj) :
280 _builder(shuffler), _orig_obj(orig_obj), _new_obj(new_obj) {}
281
282 // This method gets called once for each pointer field F of orig_obj.
283 // We update new_obj->F to point to the new location of orig_obj->F.
284 //
285 // Example: Klass* 0x100 is copied to 0x400
286 // Symbol* 0x200 is copied to 0x500
287 //
288 // Let orig_obj == 0x100; and
289 // new_obj == 0x400; and
290 // ((Klass*)orig_obj)->_name == 0x200;
291 // Then this function effectively assigns
292 // ((Klass*)new_obj)->_name = 0x500;
293 virtual bool do_ref(Ref* ref, bool read_only) {
294 address new_pointee = NULL;
295
296 if (ref->not_null()) {
297 address old_pointee = ref->obj();
298
299 FollowMode mode = _builder->follow_ref(ref);
300 if (mode == point_to_it) {
301 new_pointee = old_pointee;
302 } else if (mode == set_to_null) {
303 new_pointee = NULL;
304 } else {
305 new_pointee = _builder->get_new_loc(old_pointee);
306 }
307 }
308
309 const char* kind = MetaspaceObj::type_name(ref->msotype());
310 // offset of this field inside the original object
311 intx offset = (address)ref->addr() - _orig_obj;
312 _builder->update_pointer((address*)(_new_obj + offset), new_pointee, kind, offset);
313
314 // We can't mark the pointer here, because DynamicArchiveBuilder::sort_methods
315 // may re-layout the [iv]tables, which would change the offset(s) in an InstanceKlass
316 // that would contain pointers. Therefore, we must mark the pointers after
317 // sort_methods(), using PointerMarker.
318 return false; // Do not recurse.
319 }
320 };
321
322 class ExternalRefUpdater: public MetaspaceClosure {
323 DynamicArchiveBuilder* _builder;
324
325 public:
326 ExternalRefUpdater(DynamicArchiveBuilder* shuffler) : _builder(shuffler) {}
327
328 virtual bool do_ref(Ref* ref, bool read_only) {
329 // ref is a pointer that lives OUTSIDE of the buffer, but points to an object inside the buffer
330 if (ref->not_null()) {
331 address new_loc = _builder->get_new_loc(ref);
332 const char* kind = MetaspaceObj::type_name(ref->msotype());
333 _builder->update_pointer(ref->addr(), new_loc, kind, 0);
334 _builder->mark_pointer(ref->addr());
335 }
336 return false; // Do not recurse.
337 }
338 };
339
340 class PointerMarker: public UniqueMetaspaceClosure {
341 DynamicArchiveBuilder* _builder;
342
343 public:
344 PointerMarker(DynamicArchiveBuilder* shuffler) : _builder(shuffler) {}
345
346 virtual bool do_unique_ref(Ref* ref, bool read_only) {
347 if (_builder->is_in_buffer_space(ref->obj())) {
348 EmbeddedRefMarker ref_marker(_builder);
349 ref->metaspace_pointers_do(&ref_marker);
350 return true; // keep recursing until every buffered object is visited exactly once.
351 } else {
352 return false;
353 }
354 }
355 };
356
357 class EmbeddedRefMarker: public MetaspaceClosure {
358 DynamicArchiveBuilder* _builder;
359
360 public:
361 EmbeddedRefMarker(DynamicArchiveBuilder* shuffler) : _builder(shuffler) {}
362 virtual bool do_ref(Ref* ref, bool read_only) {
363 if (ref->not_null()) {
364 _builder->mark_pointer(ref->addr());
365 }
366 return false; // Do not recurse.
367 }
368 };
369
370 void update_pointer(address* addr, address value, const char* kind, uintx offset, bool is_mso_pointer=true) {
371 // Propagate the the mask bits to the new value -- see comments above MetaspaceClosure::obj()
372 if (is_mso_pointer) {
373 const uintx FLAG_MASK = 0x03;
374 uintx mask_bits = uintx(*addr) & FLAG_MASK;
375 value = (address)(uintx(value) | mask_bits);
376 }
377
378 if (*addr != value) {
379 log_debug(cds, dynamic)("Update (%18s*) %3d [" PTR_FORMAT "] " PTR_FORMAT " -> " PTR_FORMAT,
380 kind, int(offset), p2i(addr), p2i(*addr), p2i(value));
381 *addr = value;
382 }
383 }
384
385 private:
386 GrowableArray<Symbol*>* _symbols; // symbols to dump
387 GrowableArray<InstanceKlass*>* _klasses; // klasses to dump
388
389 void append(InstanceKlass* k) { _klasses->append(k); }
390 void append(Symbol* s) { _symbols->append(s); }
391
392 class GatherKlassesAndSymbols : public UniqueMetaspaceClosure {
393 DynamicArchiveBuilder* _builder;
394 bool _read_only;
395
396 public:
397 GatherKlassesAndSymbols(DynamicArchiveBuilder* builder)
398 : _builder(builder) {}
399
400 virtual bool do_unique_ref(Ref* ref, bool read_only) {
401 if (_builder->follow_ref(ref) != make_a_copy) {
402 return false;
403 }
404 if (ref->msotype() == MetaspaceObj::ClassType) {
405 Klass* klass = (Klass*)ref->obj();
406 assert(klass->is_klass(), "must be");
407 if (klass->is_instance_klass()) {
408 InstanceKlass* ik = InstanceKlass::cast(klass);
409 assert(!SystemDictionaryShared::is_excluded_class(ik), "must be");
410 _builder->append(ik);
411 _builder->_estimated_metsapceobj_bytes += BytesPerWord; // See RunTimeSharedClassInfo::get_for()
412 }
413 } else if (ref->msotype() == MetaspaceObj::SymbolType) {
414 _builder->append((Symbol*)ref->obj());
415 }
416
417 int bytes = ref->size() * BytesPerWord;
418 _builder->_estimated_metsapceobj_bytes += bytes;
419
420 return true;
421 }
422 };
423
424 FollowMode follow_ref(MetaspaceClosure::Ref *ref) {
425 address obj = ref->obj();
426 if (MetaspaceShared::is_in_shared_metaspace(obj)) {
427 // Don't dump existing shared metadata again.
428 return point_to_it;
429 } else if (ref->msotype() == MetaspaceObj::MethodDataType) {
430 return set_to_null;
431 } else {
432 if (ref->msotype() == MetaspaceObj::ClassType) {
433 Klass* klass = (Klass*)ref->obj();
434 assert(klass->is_klass(), "must be");
435 if (klass->is_instance_klass()) {
436 InstanceKlass* ik = InstanceKlass::cast(klass);
437 if (SystemDictionaryShared::is_excluded_class(ik)) {
438 ResourceMark rm;
439 log_debug(cds, dynamic)("Skipping class (excluded): %s", klass->external_name());
440 return set_to_null;
441 }
442 } else if (klass->is_array_klass()) {
443 // Don't support archiving of array klasses for now.
444 ResourceMark rm;
445 log_debug(cds, dynamic)("Skipping class (array): %s", klass->external_name());
446 return set_to_null;
447 }
448 }
449
450 return make_a_copy;
451 }
452 }
453
454 address copy_impl(MetaspaceClosure::Ref* ref, bool read_only, int bytes) {
455 if (ref->msotype() == MetaspaceObj::ClassType) {
456 // Save a pointer immediate in front of an InstanceKlass, so
457 // we can do a quick lookup from InstanceKlass* -> RunTimeSharedClassInfo*
458 // without building another hashtable. See RunTimeSharedClassInfo::get_for()
459 // in systemDictionaryShared.cpp.
460 address obj = ref->obj();
461 Klass* klass = (Klass*)obj;
462 if (klass->is_instance_klass()) {
463 SystemDictionaryShared::validate_before_archiving(InstanceKlass::cast(klass));
464 current_dump_space()->allocate(sizeof(address), BytesPerWord);
465 }
466 }
467 address p = (address)current_dump_space()->allocate(bytes);
468 address obj = ref->obj();
469 log_debug(cds, dynamic)("COPY: " PTR_FORMAT " ==> " PTR_FORMAT " %5d %s",
470 p2i(obj), p2i(p), bytes,
471 MetaspaceObj::type_name(ref->msotype()));
472 memcpy(p, obj, bytes);
473 intptr_t* cloned_vtable = MetaspaceShared::fix_cpp_vtable_for_dynamic_archive(ref->msotype(), p);
474 if (cloned_vtable != NULL) {
475 update_pointer((address*)p, (address)cloned_vtable, "vtb", 0, /*is_mso_pointer*/false);
476 mark_pointer((address*)p);
477 }
478
479 return (address)p;
480 }
481
482 DynamicArchiveHeader *_header;
483 address _alloc_bottom;
484 address _last_verified_top;
485 size_t _other_region_used_bytes;
486
487 // Conservative estimate for number of bytes needed for:
488 size_t _estimated_metsapceobj_bytes; // all archived MetsapceObj's.
489 size_t _estimated_hashtable_bytes; // symbol table and dictionaries
490 size_t _estimated_trampoline_bytes; // method entry trampolines
491
492 size_t estimate_archive_size();
493 size_t estimate_trampoline_size();
494 size_t estimate_class_file_size();
495 address reserve_space_and_init_buffer_to_target_delta();
496 void init_header(address addr);
497 void release_header();
498 void make_trampolines();
499 void make_klasses_shareable();
500 void sort_methods(InstanceKlass* ik) const;
501 void set_symbols_permanent();
502 void relocate_buffer_to_target();
503 void write_archive(char* serialized_data);
504
505 void init_first_dump_space(address reserved_bottom) {
506 address first_space_base = reserved_bottom;
507 DumpRegion* mc_space = MetaspaceShared::misc_code_dump_space();
508 DumpRegion* rw_space = MetaspaceShared::read_write_dump_space();
509
510 // Use the same MC->RW->RO ordering as in the base archive.
511 MetaspaceShared::init_shared_dump_space(mc_space, first_space_base);
512 _current_dump_space = mc_space;
513 _last_verified_top = first_space_base;
514 _num_dump_regions_used = 1;
515 }
516
517 void reserve_buffers_for_trampolines() {
518 size_t n = _estimated_trampoline_bytes;
519 assert(n >= SharedRuntime::trampoline_size(), "dont want to be empty");
520 MetaspaceShared::misc_code_space_alloc(n);
521 }
522
523 public:
524 DynamicArchiveBuilder() {
525 _klasses = new (ResourceObj::C_HEAP, mtClass) GrowableArray<InstanceKlass*>(100, true, mtInternal);
526 _symbols = new (ResourceObj::C_HEAP, mtClass) GrowableArray<Symbol*>(1000, true, mtInternal);
527
528 _estimated_metsapceobj_bytes = 0;
529 _estimated_hashtable_bytes = 0;
530 _estimated_trampoline_bytes = 0;
531
532 _num_dump_regions_used = 0;
533 }
534
535 void start_dump_space(DumpRegion* next) {
536 address bottom = _last_verified_top;
537 address top = (address)(current_dump_space()->top());
538 _other_region_used_bytes += size_t(top - bottom);
539
540 MetaspaceShared::pack_dump_space(current_dump_space(), next, MetaspaceShared::shared_rs());
541 _current_dump_space = next;
542 _num_dump_regions_used ++;
543
544 _last_verified_top = (address)(current_dump_space()->top());
545 }
546
547 void verify_estimate_size(size_t estimate, const char* which) {
548 address bottom = _last_verified_top;
549 address top = (address)(current_dump_space()->top());
550 size_t used = size_t(top - bottom) + _other_region_used_bytes;
551 int diff = int(estimate) - int(used);
552
553 log_info(cds)("%s estimate = " SIZE_FORMAT " used = " SIZE_FORMAT "; diff = %d bytes", which, estimate, used, diff);
554 assert(diff >= 0, "Estimate is too small");
555
556 _last_verified_top = top;
557 _other_region_used_bytes = 0;
558 }
559
560 // Do this before and after the archive dump to see if any corruption
561 // is caused by dynamic dumping.
562 void verify_universe(const char* info) {
563 if (VerifyBeforeExit) {
564 log_info(cds)("Verify %s", info);
565 HandleMark hm;
566 // Among other things, this ensures that Eden top is correct.
567 Universe::heap()->prepare_for_verify();
568 Universe::verify(info);
569 }
570 }
571
572 void doit() {
573 verify_universe("Before CDS dynamic dump");
574 DEBUG_ONLY(SystemDictionaryShared::NoClassLoadingMark nclm);
575 SystemDictionaryShared::check_excluded_classes();
576
577 {
578 ResourceMark rm;
579 GatherKlassesAndSymbols gatherer(this);
580
581 SystemDictionaryShared::dumptime_classes_do(&gatherer);
582 SymbolTable::metaspace_pointers_do(&gatherer);
583 FileMapInfo::metaspace_pointers_do(&gatherer);
584
585 gatherer.finish();
586 }
587
588 // rw space starts ...
589 address reserved_bottom = reserve_space_and_init_buffer_to_target_delta();
590 init_header(reserved_bottom);
591
592 CHeapBitMap ptrmap;
593 ArchivePtrMarker::initialize(&ptrmap, (address*)reserved_bottom, (address*)current_dump_space()->top());
594
595 reserve_buffers_for_trampolines();
596 verify_estimate_size(_estimated_trampoline_bytes, "Trampolines");
597
598 start_dump_space(MetaspaceShared::read_write_dump_space());
599
600 log_info(cds, dynamic)("Copying %d klasses and %d symbols",
601 _klasses->length(), _symbols->length());
602
603 {
604 assert(current_dump_space() == MetaspaceShared::read_write_dump_space(),
605 "Current dump space is not rw space");
606 // shallow-copy RW objects, if necessary
607 ResourceMark rm;
608 ShallowCopier rw_copier(this, false);
609 iterate_roots(&rw_copier);
610 }
611
612 // ro space starts ...
613 DumpRegion* ro_space = MetaspaceShared::read_only_dump_space();
614 {
615 start_dump_space(ro_space);
616
617 // shallow-copy RO objects, if necessary
618 ResourceMark rm;
619 ShallowCopier ro_copier(this, true);
620 iterate_roots(&ro_copier);
621 }
622
623 {
624 log_info(cds)("Relocating embedded pointers ... ");
625 ResourceMark rm;
626 ShallowCopyEmbeddedRefRelocator emb_reloc(this);
627 iterate_roots(&emb_reloc);
628 }
629
630 {
631 log_info(cds)("Relocating external roots ... ");
632 ResourceMark rm;
633 ExternalRefUpdater ext_reloc(this);
634 iterate_roots(&ext_reloc);
635 }
636
637 verify_estimate_size(_estimated_metsapceobj_bytes, "MetaspaceObjs");
638
639 char* serialized_data;
640 {
641 set_symbols_permanent();
642
643 // Write the symbol table and system dictionaries to the RO space.
644 // Note that these tables still point to the *original* objects
645 // (because they were not processed by ExternalRefUpdater), so
646 // they would need to call DynamicArchive::original_to_target() to
647 // get the correct addresses.
648 assert(current_dump_space() == ro_space, "Must be RO space");
649 SymbolTable::write_to_archive(false);
650 SystemDictionaryShared::write_to_archive(false);
651
652 serialized_data = ro_space->top();
653 WriteClosure wc(ro_space);
654 SymbolTable::serialize_shared_table_header(&wc, false);
655 SystemDictionaryShared::serialize_dictionary_headers(&wc, false);
656 }
657
658 verify_estimate_size(_estimated_hashtable_bytes, "Hashtables");
659
660 make_trampolines();
661 make_klasses_shareable();
662
663 {
664 log_info(cds)("Final relocation of pointers ... ");
665 ResourceMark rm;
666 PointerMarker marker(this);
667 iterate_roots(&marker);
668 relocate_buffer_to_target();
669 }
670
671 write_archive(serialized_data);
672 release_header();
673
674 assert(_num_dump_regions_used == _total_dump_regions, "must be");
675 verify_universe("After CDS dynamic dump");
676 }
677
678 void iterate_roots(MetaspaceClosure* it) {
679 int i;
680 int num_klasses = _klasses->length();
681 for (i = 0; i < num_klasses; i++) {
682 it->push(&_klasses->at(i));
683 }
684
685 int num_symbols = _symbols->length();
686 for (i = 0; i < num_symbols; i++) {
687 it->push(&_symbols->at(i));
688 }
689
690 FileMapInfo::metaspace_pointers_do(it);
691
692 // Do not call these again, as we have already collected all the classes and symbols
693 // that we want to archive. Also, these calls would corrupt the tables when
694 // ExternalRefUpdater is used.
695 //
696 // SystemDictionaryShared::dumptime_classes_do(it);
697 // SymbolTable::metaspace_pointers_do(it);
698
699 it->finish();
700 }
701 };
702
703 intx DynamicArchiveBuilder::_buffer_to_target_delta;
704
705
706 size_t DynamicArchiveBuilder::estimate_archive_size() {
707 // size of the symbol table and two dictionaries, plus the RunTimeSharedClassInfo's
708 _estimated_hashtable_bytes = 0;
709 _estimated_hashtable_bytes += SymbolTable::estimate_size_for_archive();
710 _estimated_hashtable_bytes += SystemDictionaryShared::estimate_size_for_archive();
711
712 _estimated_trampoline_bytes = estimate_trampoline_size();
713
714 size_t total = 0;
715
716 total += _estimated_metsapceobj_bytes;
717 total += _estimated_hashtable_bytes;
718 total += _estimated_trampoline_bytes;
719
720 // allow fragmentation at the end of each dump region
721 total += _total_dump_regions * reserve_alignment();
722
723 return align_up(total, reserve_alignment());
724 }
725
726 address DynamicArchiveBuilder::reserve_space_and_init_buffer_to_target_delta() {
727 size_t total = estimate_archive_size();
728 ReservedSpace rs = MetaspaceShared::reserve_shared_space(total);
729 if (!rs.is_reserved()) {
730 log_error(cds, dynamic)("Failed to reserve %d bytes of output buffer.", (int)total);
731 vm_direct_exit(0);
732 }
733
734 address buffer_base = (address)rs.base();
735 log_info(cds, dynamic)("Reserved output buffer space at : " PTR_FORMAT " [%d bytes]",
736 p2i(buffer_base), (int)total);
737 MetaspaceShared::set_shared_rs(rs);
738
739 // At run time, we will mmap the dynamic archive at target_space_bottom.
740 // However, at dump time, we may not be able to write into the target_space,
741 // as it's occupied by dynamically loaded Klasses. So we allocate a buffer
742 // at an arbitrary location chosen by the OS. We will write all the dynamically
743 // archived classes into this buffer. At the final stage of dumping, we relocate
744 // all pointers that are inside the buffer_space to point to their (runtime)
745 // target location inside thetarget_space.
746 address target_space_bottom =
747 (address)align_up(MetaspaceShared::shared_metaspace_top(), reserve_alignment());
748 _buffer_to_target_delta = intx(target_space_bottom) - intx(buffer_base);
749
750 log_info(cds, dynamic)("Target archive space at : " PTR_FORMAT, p2i(target_space_bottom));
751 log_info(cds, dynamic)("Buffer-space to target-space delta : " PTR_FORMAT, p2i((address)_buffer_to_target_delta));
752
753 return buffer_base;
754 }
755
756 void DynamicArchiveBuilder::init_header(address reserved_bottom) {
757 _alloc_bottom = reserved_bottom;
758 _last_verified_top = reserved_bottom;
759 _other_region_used_bytes = 0;
760
761 init_first_dump_space(reserved_bottom);
762
763 FileMapInfo* mapinfo = new FileMapInfo(false);
764 assert(FileMapInfo::dynamic_info() == mapinfo, "must be");
765 _header = mapinfo->dynamic_header();
766
767 Thread* THREAD = Thread::current();
768 FileMapInfo* base_info = FileMapInfo::current_info();
769 _header->set_base_header_crc(base_info->crc());
770 for (int i = 0; i < MetaspaceShared::n_regions; i++) {
771 _header->set_base_region_crc(i, base_info->space_crc(i));
772 }
773 _header->populate(base_info, os::vm_allocation_granularity());
774 }
775
776 void DynamicArchiveBuilder::release_header() {
777 // We temporarily allocated a dynamic FileMapInfo for dumping, which makes it appear we
778 // have mapped a dynamic archive, but we actually have not. We are in a safepoint now.
779 // Let's free it so that if class loading happens after we leave the safepoint, nothing
780 // bad will happen.
781 assert(SafepointSynchronize::is_at_safepoint(), "must be");
782 FileMapInfo *mapinfo = FileMapInfo::dynamic_info();
783 assert(mapinfo != NULL && _header == mapinfo->dynamic_header(), "must be");
784 delete mapinfo;
785 assert(!DynamicArchive::is_mapped(), "must be");
786 _header = NULL;
787 }
788
789 size_t DynamicArchiveBuilder::estimate_trampoline_size() {
790 size_t total = 0;
791 size_t each_method_bytes =
792 align_up(SharedRuntime::trampoline_size(), BytesPerWord) +
793 align_up(sizeof(AdapterHandlerEntry*), BytesPerWord);
794
795 for (int i = 0; i < _klasses->length(); i++) {
796 InstanceKlass* ik = _klasses->at(i);
797 Array<Method*>* methods = ik->methods();
798 total += each_method_bytes * methods->length();
799 }
800 if (total == 0) {
801 // We have nothing to archive, but let's avoid having an empty region.
802 total = SharedRuntime::trampoline_size();
803 }
804 return total;
805 }
806
807 void DynamicArchiveBuilder::make_trampolines() {
808 DumpRegion* mc_space = MetaspaceShared::misc_code_dump_space();
809 char* p = mc_space->base();
810 for (int i = 0; i < _klasses->length(); i++) {
811 InstanceKlass* ik = _klasses->at(i);
812 Array<Method*>* methods = ik->methods();
813 for (int j = 0; j < methods->length(); j++) {
814 Method* m = methods->at(j);
815 address c2i_entry_trampoline = (address)p;
816 p += SharedRuntime::trampoline_size();
817 assert(p >= mc_space->base() && p <= mc_space->top(), "must be");
818 m->set_from_compiled_entry(to_target(c2i_entry_trampoline));
819
820 AdapterHandlerEntry** adapter_trampoline =(AdapterHandlerEntry**)p;
821 p += sizeof(AdapterHandlerEntry*);
822 assert(p >= mc_space->base() && p <= mc_space->top(), "must be");
823 *adapter_trampoline = NULL;
824 m->set_adapter_trampoline(to_target(adapter_trampoline));
825 }
826 }
827
828 guarantee(p <= mc_space->top(), "Estimate of trampoline size is insufficient");
829 }
830
831 void DynamicArchiveBuilder::make_klasses_shareable() {
832 int i, count = _klasses->length();
833
834 InstanceKlass::disable_method_binary_search();
835 for (i = 0; i < count; i++) {
836 InstanceKlass* ik = _klasses->at(i);
837 sort_methods(ik);
838 }
839
840 for (i = 0; i < count; i++) {
841 InstanceKlass* ik = _klasses->at(i);
842 ClassLoaderData *cld = ik->class_loader_data();
843 if (cld->is_boot_class_loader_data()) {
844 ik->set_shared_class_loader_type(ClassLoader::BOOT_LOADER);
845 }
846 else if (cld->is_platform_class_loader_data()) {
847 ik->set_shared_class_loader_type(ClassLoader::PLATFORM_LOADER);
848 }
849 else if (cld->is_system_class_loader_data()) {
850 ik->set_shared_class_loader_type(ClassLoader::APP_LOADER);
851 }
852
853 MetaspaceShared::rewrite_nofast_bytecodes_and_calculate_fingerprints(Thread::current(), ik);
854 ik->remove_unshareable_info();
855
856 assert(ik->array_klasses() == NULL, "sanity");
857
858 if (log_is_enabled(Debug, cds, dynamic)) {
859 ResourceMark rm;
860 log_debug(cds, dynamic)("klasses[%4i] = " PTR_FORMAT " %s", i, p2i(to_target(ik)), ik->external_name());
861 }
862 }
863 }
864
865 // The address order of the copied Symbols may be different than when the original
866 // klasses were created. Re-sort all the tables. See Method::sort_methods().
867 void DynamicArchiveBuilder::sort_methods(InstanceKlass* ik) const {
868 assert(ik != NULL, "DynamicArchiveBuilder currently doesn't support dumping the base archive");
869 if (MetaspaceShared::is_in_shared_metaspace(ik)) {
870 // We have reached a supertype that's already in the base archive
871 return;
872 }
873
874 if (ik->java_mirror() == NULL) {
875 // NULL mirror means this class has already been visited and methods are already sorted
876 return;
877 }
878 ik->remove_java_mirror();
879
880 if (log_is_enabled(Debug, cds, dynamic)) {
881 ResourceMark rm;
882 log_debug(cds, dynamic)("sorting methods for " PTR_FORMAT " %s", p2i(to_target(ik)), ik->external_name());
883 }
884
885 // Make sure all supertypes have been sorted
886 sort_methods(ik->java_super());
887 Array<InstanceKlass*>* interfaces = ik->local_interfaces();
888 int len = interfaces->length();
889 for (int i = 0; i < len; i++) {
890 sort_methods(interfaces->at(i));
891 }
892
893 #ifdef ASSERT
894 if (ik->methods() != NULL) {
895 for (int m = 0; m < ik->methods()->length(); m++) {
896 Symbol* name = ik->methods()->at(m)->name();
897 assert(MetaspaceShared::is_in_shared_metaspace(name) || is_in_buffer_space(name), "must be");
898 }
899 }
900 if (ik->default_methods() != NULL) {
901 for (int m = 0; m < ik->default_methods()->length(); m++) {
902 Symbol* name = ik->default_methods()->at(m)->name();
903 assert(MetaspaceShared::is_in_shared_metaspace(name) || is_in_buffer_space(name), "must be");
904 }
905 }
906 #endif
907
908 Thread* THREAD = Thread::current();
909 Method::sort_methods(ik->methods(), /*set_idnums=*/true, dynamic_dump_method_comparator);
910 if (ik->default_methods() != NULL) {
911 Method::sort_methods(ik->default_methods(), /*set_idnums=*/false, dynamic_dump_method_comparator);
912 }
913 ik->vtable().initialize_vtable(true, THREAD); assert(!HAS_PENDING_EXCEPTION, "cannot fail");
914 ik->itable().initialize_itable(true, THREAD); assert(!HAS_PENDING_EXCEPTION, "cannot fail");
915 }
916
917 void DynamicArchiveBuilder::set_symbols_permanent() {
918 int count = _symbols->length();
919 for (int i=0; i<count; i++) {
920 Symbol* s = _symbols->at(i);
921 s->set_permanent();
922
923 if (log_is_enabled(Trace, cds, dynamic)) {
924 ResourceMark rm;
925 log_trace(cds, dynamic)("symbols[%4i] = " PTR_FORMAT " %s", i, p2i(to_target(s)), s->as_quoted_ascii());
926 }
927 }
928 }
929
930 class RelocateBufferToTarget: public BitMapClosure {
931 DynamicArchiveBuilder *_builder;
932 address* _buffer_bottom;
933 intx _buffer_to_target_delta;
934 public:
935 RelocateBufferToTarget(DynamicArchiveBuilder* builder, address* bottom, intx delta) :
936 _builder(builder), _buffer_bottom(bottom), _buffer_to_target_delta(delta) {}
937
938 bool do_bit(size_t offset) {
939 address* p = _buffer_bottom + offset;
940 assert(_builder->is_in_buffer_space(p), "pointer must live in buffer space");
941
942 address old_ptr = *p;
943 if (_builder->is_in_buffer_space(old_ptr)) {
944 address new_ptr = old_ptr + _buffer_to_target_delta;
945 log_trace(cds, dynamic)("Final patch: @%6d [" PTR_FORMAT " -> " PTR_FORMAT "] " PTR_FORMAT " => " PTR_FORMAT,
946 (int)offset, p2i(p), p2i(_builder->to_target(p)),
947 p2i(old_ptr), p2i(new_ptr));
948 *p = new_ptr;
949 }
950
951 return true; // keep iterating
952 }
953 };
954
955 void DynamicArchiveBuilder::relocate_buffer_to_target() {
956 RelocateBufferToTarget patcher(this, (address*)_alloc_bottom, _buffer_to_target_delta);
957 ArchivePtrMarker::ptrmap()->iterate(&patcher);
958
959 Array<u8>* table = FileMapInfo::saved_shared_path_table().table();
960 SharedPathTable runtime_table(to_target(table), FileMapInfo::shared_path_table().size());
961 _header->set_shared_path_table(runtime_table);
962
963 address relocatable_base = (address)SharedBaseAddress;
964 address relocatable_end = (address)(current_dump_space()->top()) + _buffer_to_target_delta;
965
966 intx addr_delta = MetaspaceShared::final_delta();
967 if (addr_delta == 0) {
968 ArchivePtrMarker::compact(relocatable_base, relocatable_end);
969 } else {
970 // The base archive is NOT mapped at MetaspaceShared::default_base_address() (due to ASLR).
971 // This means that the current content of the dynamic archive is based on a random
972 // address. Let's relocate all the pointers, so that it can be mapped to
973 // MetaspaceShared::default_base_address() without runtime relocation.
974 //
975 // Note: both the base and dynamic archive are written with
976 // FileMapHeader::_shared_base_address == MetaspaceShared::default_base_address()
977
978 // Patch all pointers that are marked by ptrmap within this region,
979 // where we have just dumped all the metaspace data.
980 address patch_base = (address)_alloc_bottom;
981 address patch_end = (address)current_dump_space()->top();
982
983 // the current value of the pointers to be patched must be within this
984 // range (i.e., must point to either the top archive (as currently mapped), or to the
985 // (targeted address of) the top archive)
986 address valid_old_base = relocatable_base;
987 address valid_old_end = relocatable_end;
988 size_t base_plus_top_size = valid_old_end - valid_old_base;
989 size_t top_size = patch_end - patch_base;
990 size_t base_size = base_plus_top_size - top_size;
991 assert(base_plus_top_size > base_size, "no overflow");
992 assert(base_plus_top_size > top_size, "no overflow");
993
994 // after patching, the pointers must point inside this range
995 // (the requested location of the archive, as mapped at runtime).
996 address valid_new_base = (address)MetaspaceShared::default_base_address();
997 address valid_new_end = valid_new_base + base_plus_top_size;
998
999 log_debug(cds)("Relocating archive from [" INTPTR_FORMAT " - " INTPTR_FORMAT "] to "
1000 "[" INTPTR_FORMAT " - " INTPTR_FORMAT "], delta = " INTX_FORMAT " bytes",
1001 p2i(patch_base + base_size), p2i(patch_end),
1002 p2i(valid_new_base + base_size), p2i(valid_new_end), addr_delta);
1003
1004 SharedDataRelocator<true> patcher((address*)patch_base, (address*)patch_end, valid_old_base, valid_old_end,
1005 valid_new_base, valid_new_end, addr_delta, ArchivePtrMarker::ptrmap());
1006 ArchivePtrMarker::ptrmap()->iterate(&patcher);
1007 ArchivePtrMarker::compact(patcher.max_non_null_offset());
1008 }
1009 }
1010
1011 void DynamicArchiveBuilder::write_archive(char* serialized_data) {
1012 int num_klasses = _klasses->length();
1013 int num_symbols = _symbols->length();
1014
1015 _header->set_serialized_data(to_target(serialized_data));
1016
1017 FileMapInfo* dynamic_info = FileMapInfo::dynamic_info();
1018 assert(dynamic_info != NULL, "Sanity");
1019
1020 // Now write the archived data including the file offsets.
1021 const char* archive_name = Arguments::GetSharedDynamicArchivePath();
1022 dynamic_info->open_for_write(archive_name);
1023 MetaspaceShared::write_core_archive_regions(dynamic_info, NULL, NULL);
1024 dynamic_info->set_final_requested_base((char*)MetaspaceShared::default_base_address());
1025 dynamic_info->set_header_crc(dynamic_info->compute_header_crc());
1026 dynamic_info->write_header();
1027 dynamic_info->close();
1028
1029 address base = to_target(_alloc_bottom);
1030 address top = address(current_dump_space()->top()) + _buffer_to_target_delta;
1031 size_t file_size = pointer_delta(top, base, sizeof(char));
1032
1033 base += MetaspaceShared::final_delta();
1034 top += MetaspaceShared::final_delta();
1035 log_info(cds, dynamic)("Written dynamic archive " PTR_FORMAT " - " PTR_FORMAT
1036 " [" SIZE_FORMAT " bytes header, " SIZE_FORMAT " bytes total]",
1037 p2i(base), p2i(top), _header->header_size(), file_size);
1038 log_info(cds, dynamic)("%d klasses; %d symbols", num_klasses, num_symbols);
1039 }
1040
1041
1042 class VM_PopulateDynamicDumpSharedSpace: public VM_Operation {
1043 DynamicArchiveBuilder* _builder;
1044 public:
1045 VM_PopulateDynamicDumpSharedSpace(DynamicArchiveBuilder* builder) : _builder(builder) {}
1046 VMOp_Type type() const { return VMOp_PopulateDumpSharedSpace; }
1047 void doit() {
1048 ResourceMark rm;
1049 if (SystemDictionaryShared::empty_dumptime_table()) {
1050 log_warning(cds, dynamic)("There is no class to be included in the dynamic archive.");
1051 return;
1052 }
1053 if (AllowArchivingWithJavaAgent) {
1054 warning("This archive was created with AllowArchivingWithJavaAgent. It should be used "
1055 "for testing purposes only and should not be used in a production environment");
1056 }
1057 FileMapInfo::check_nonempty_dir_in_shared_path_table();
1058
1059 _builder->doit();
1060 }
1061 };
1062
1063
1064 void DynamicArchive::dump() {
1065 if (Arguments::GetSharedDynamicArchivePath() == NULL) {
1066 log_warning(cds, dynamic)("SharedDynamicArchivePath is not specified");
1067 return;
1068 }
1069
1070 DynamicArchiveBuilder builder;
1071 _builder = &builder;
1072 VM_PopulateDynamicDumpSharedSpace op(&builder);
1073 VMThread::execute(&op);
1074 _builder = NULL;
1075 }
1076
1077 address DynamicArchive::original_to_buffer_impl(address orig_obj) {
1078 assert(DynamicDumpSharedSpaces, "must be");
1079 address buff_obj = _builder->get_new_loc(orig_obj);
1080 assert(buff_obj != NULL, "orig_obj must be used by the dynamic archive");
1081 assert(buff_obj != orig_obj, "call this only when you know orig_obj must be copied and not just referenced");
1082 assert(_builder->is_in_buffer_space(buff_obj), "must be");
1083 return buff_obj;
1084 }
1085
1086 address DynamicArchive::buffer_to_target_impl(address buff_obj) {
1087 assert(DynamicDumpSharedSpaces, "must be");
1088 assert(_builder->is_in_buffer_space(buff_obj), "must be");
1089 return _builder->to_target(buff_obj);
1090 }
1091
1092 address DynamicArchive::original_to_target_impl(address orig_obj) {
1093 assert(DynamicDumpSharedSpaces, "must be");
1094 if (MetaspaceShared::is_in_shared_metaspace(orig_obj)) {
1095 // This happens when the top archive points to a Symbol* in the base archive.
1096 return orig_obj;
1097 }
1098 address buff_obj = _builder->get_new_loc(orig_obj);
1099 assert(buff_obj != NULL, "orig_obj must be used by the dynamic archive");
1100 if (buff_obj == orig_obj) {
1101 // We are storing a pointer to an original object into the dynamic buffer. E.g.,
1102 // a Symbol* that used by both the base and top archives.
1103 assert(MetaspaceShared::is_in_shared_metaspace(orig_obj), "must be");
1104 return orig_obj;
1105 } else {
1106 return _builder->to_target(buff_obj);
1107 }
1108 }
1109
1110 uintx DynamicArchive::object_delta_uintx(void* buff_obj) {
1111 assert(DynamicDumpSharedSpaces, "must be");
1112 address target_obj = _builder->to_target_no_check(address(buff_obj));
1113 assert(uintx(target_obj) >= SharedBaseAddress, "must be");
1114 return uintx(target_obj) - SharedBaseAddress;
1115 }
1116
1117 bool DynamicArchive::is_in_target_space(void *obj) {
1118 assert(DynamicDumpSharedSpaces, "must be");
1119 return _builder->is_in_target_space(obj);
1120 }
1121
1122
1123 DynamicArchiveBuilder* DynamicArchive::_builder = NULL;
1124
1125
1126 bool DynamicArchive::validate(FileMapInfo* dynamic_info) {
1127 // Check if the recorded base archive matches with the current one
1128 FileMapInfo* base_info = FileMapInfo::current_info();
1129 DynamicArchiveHeader* dynamic_header = dynamic_info->dynamic_header();
1130
1131 // Check the header crc
1132 if (dynamic_header->base_header_crc() != base_info->crc()) {
1133 FileMapInfo::fail_continue("Archive header checksum verification failed.");
1134 return false;
1135 }
1136
1137 // Check each space's crc
1138 for (int i = 0; i < MetaspaceShared::n_regions; i++) {
1139 if (dynamic_header->base_region_crc(i) != base_info->space_crc(i)) {
1140 FileMapInfo::fail_continue("Archive region #%d checksum verification failed.", i);
1141 return false;
1142 }
1143 }
1144
1145 // Validate the dynamic archived shared path table, and set the global
1146 // _shared_path_table to that.
1147 if (!dynamic_info->validate_shared_path_table()) {
1148 return false;
1149 }
1150 return true;
1151 }