1 /*
2 * Copyright (c) 2012, 2015, 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 "classfile/dictionary.hpp"
27 #include "classfile/loaderConstraints.hpp"
28 #include "classfile/placeholders.hpp"
29 #include "classfile/sharedClassUtil.hpp"
30 #include "classfile/symbolTable.hpp"
31 #include "classfile/systemDictionary.hpp"
32 #include "code/codeCache.hpp"
33 #include "interpreter/bytecodes.hpp"
34 #include "interpreter/bytecodeStream.hpp"
35 #include "memory/filemap.hpp"
36 #include "memory/gcLocker.hpp"
37 #include "memory/metaspace.hpp"
38 #include "memory/metaspaceShared.hpp"
39 #include "oops/objArrayOop.hpp"
40 #include "oops/oop.inline.hpp"
41 #include "runtime/os.hpp"
42 #include "runtime/signature.hpp"
43 #include "runtime/vm_operations.hpp"
44 #include "runtime/vmThread.hpp"
45 #include "utilities/hashtable.inline.hpp"
46
47 PRAGMA_FORMAT_MUTE_WARNINGS_FOR_GCC
48
49 int MetaspaceShared::_max_alignment = 0;
50
51 ReservedSpace* MetaspaceShared::_shared_rs = NULL;
52
53 MetaspaceSharedStats MetaspaceShared::_stats;
54
55 bool MetaspaceShared::_link_classes_made_progress;
56 bool MetaspaceShared::_check_classes_made_progress;
57 bool MetaspaceShared::_has_error_classes;
58 bool MetaspaceShared::_archive_loading_failed = false;
59 // Read/write a data stream for restoring/preserving metadata pointers and
60 // miscellaneous data from/to the shared archive file.
61
62 void MetaspaceShared::serialize(SerializeClosure* soc) {
63 int tag = 0;
64 soc->do_tag(--tag);
65
66 // Verify the sizes of various metadata in the system.
67 soc->do_tag(sizeof(Method));
68 soc->do_tag(sizeof(ConstMethod));
69 soc->do_tag(arrayOopDesc::base_offset_in_bytes(T_BYTE));
70 soc->do_tag(sizeof(ConstantPool));
71 soc->do_tag(sizeof(ConstantPoolCache));
72 soc->do_tag(objArrayOopDesc::base_offset_in_bytes());
73 soc->do_tag(typeArrayOopDesc::base_offset_in_bytes(T_BYTE));
74 soc->do_tag(sizeof(Symbol));
75
76 // Dump/restore miscellaneous metadata.
77 Universe::serialize(soc, true);
78 soc->do_tag(--tag);
79
80 // Dump/restore references to commonly used names and signatures.
81 vmSymbols::serialize(soc);
82 soc->do_tag(--tag);
83
84 soc->do_tag(666);
85 }
86
87
88 // CDS code for dumping shared archive.
89
90 // Global object for holding classes that have been loaded. Since this
91 // is run at a safepoint just before exit, this is the entire set of classes.
92 static GrowableArray<Klass*>* _global_klass_objects;
93 static void collect_classes(Klass* k) {
94 _global_klass_objects->append_if_missing(k);
95 if (k->oop_is_instance()) {
96 // Add in the array classes too
97 InstanceKlass* ik = InstanceKlass::cast(k);
98 ik->array_klasses_do(collect_classes);
99 }
100 }
101
102 static void remove_unshareable_in_classes() {
103 for (int i = 0; i < _global_klass_objects->length(); i++) {
104 Klass* k = _global_klass_objects->at(i);
105 k->remove_unshareable_info();
106 }
107 }
108
109 static void rewrite_nofast_bytecode(Method* method) {
110 RawBytecodeStream bcs(method);
111 while (!bcs.is_last_bytecode()) {
112 Bytecodes::Code opcode = bcs.raw_next();
113 switch (opcode) {
114 case Bytecodes::_getfield: *bcs.bcp() = Bytecodes::_nofast_getfield; break;
115 case Bytecodes::_putfield: *bcs.bcp() = Bytecodes::_nofast_putfield; break;
116 case Bytecodes::_aload_0: *bcs.bcp() = Bytecodes::_nofast_aload_0; break;
117 case Bytecodes::_iload: *bcs.bcp() = Bytecodes::_nofast_iload; break;
118 default: break;
119 }
120 }
121 }
122
123 // Walk all methods in the class list to ensure that they won't be modified at
124 // run time. This includes:
125 // [1] Rewrite all bytecodes as needed, so that the ConstMethod* will not be modified
126 // at run time by RewriteBytecodes/RewriteFrequentPairs
127 // [2] Assign a fingerprint, so one doesn't need to be assigned at run-time.
128 static void rewrite_nofast_bytecodes_and_calculate_fingerprints() {
129 for (int i = 0; i < _global_klass_objects->length(); i++) {
130 Klass* k = _global_klass_objects->at(i);
131 if (k->oop_is_instance()) {
132 InstanceKlass* ik = InstanceKlass::cast(k);
133 for (int i = 0; i < ik->methods()->length(); i++) {
134 Method* m = ik->methods()->at(i);
135 rewrite_nofast_bytecode(m);
136 Fingerprinter fp(m);
137 // The side effect of this call sets method's fingerprint field.
138 fp.fingerprint();
139 }
140 }
141 }
142 }
143
144 // Patch C++ vtable pointer in metadata.
145
146 // Klass and other metadata objects contain references to c++ vtables in the
147 // JVM library.
148 // Fix them to point to our constructed vtables. However, don't iterate
149 // across the space while doing this, as that causes the vtables to be
150 // patched, undoing our useful work. Instead, iterate to make a list,
151 // then use the list to do the fixing.
152 //
153 // Our constructed vtables:
154 // Dump time:
155 // 1. init_self_patching_vtbl_list: table of pointers to current virtual method addrs
156 // 2. generate_vtable_methods: create jump table, appended to above vtbl_list
157 // 3. patch_klass_vtables: for Klass list, patch the vtable entry in klass and
158 // associated metadata to point to jump table rather than to current vtbl
159 // Table layout: NOTE FIXED SIZE
160 // 1. vtbl pointers
161 // 2. #Klass X #virtual methods per Klass
162 // 1 entry for each, in the order:
163 // Klass1:method1 entry, Klass1:method2 entry, ... Klass1:method<num_virtuals> entry
164 // Klass2:method1 entry, Klass2:method2 entry, ... Klass2:method<num_virtuals> entry
165 // ...
166 // Klass<vtbl_list_size>:method1 entry, Klass<vtbl_list_size>:method2 entry,
167 // ... Klass<vtbl_list_size>:method<num_virtuals> entry
168 // Sample entry: (Sparc):
169 // save(sp, -256, sp)
170 // ba,pt common_code
171 // mov XXX, %L0 %L0 gets: Klass index <<8 + method index (note: max method index 255)
172 //
173 // Restore time:
174 // 1. initialize_shared_space: reserve space for table
175 // 2. init_self_patching_vtbl_list: update pointers to NEW virtual method addrs in text
176 //
177 // Execution time:
178 // First virtual method call for any object of these metadata types:
179 // 1. object->klass
180 // 2. vtable entry for that klass points to the jump table entries
181 // 3. branches to common_code with %O0/klass, %L0: Klass index <<8 + method index
182 // 4. common_code:
183 // Get address of new vtbl pointer for this Klass from updated table
184 // Update new vtbl pointer in the Klass: future virtual calls go direct
185 // Jump to method, using new vtbl pointer and method index
186
187
188 static void* find_matching_vtbl_ptr(void** vtbl_list, void* new_vtable_start, void* obj) {
189 void* old_vtbl_ptr = *(void**)obj;
190 for (int i = 0; i < MetaspaceShared::vtbl_list_size; i++) {
191 if (vtbl_list[i] == old_vtbl_ptr) {
192 return (void**)new_vtable_start + i * MetaspaceShared::num_virtuals;
193 }
194 }
195 ShouldNotReachHere();
196 return NULL;
197 }
198
199 // Assumes the vtable is in first slot in object.
200 static void patch_klass_vtables(void** vtbl_list, void* new_vtable_start) {
201 int n = _global_klass_objects->length();
202 for (int i = 0; i < n; i++) {
203 Klass* obj = _global_klass_objects->at(i);
204 // Note oop_is_instance() is a virtual call. After patching vtables
205 // all virtual calls on the dummy vtables will restore the original!
206 if (obj->oop_is_instance()) {
207 InstanceKlass* ik = InstanceKlass::cast(obj);
208 *(void**)ik = find_matching_vtbl_ptr(vtbl_list, new_vtable_start, ik);
209 ConstantPool* cp = ik->constants();
210 *(void**)cp = find_matching_vtbl_ptr(vtbl_list, new_vtable_start, cp);
211 for (int j = 0; j < ik->methods()->length(); j++) {
212 Method* m = ik->methods()->at(j);
213 *(void**)m = find_matching_vtbl_ptr(vtbl_list, new_vtable_start, m);
214 }
215 } else {
216 // Array klasses
217 Klass* k = obj;
218 *(void**)k = find_matching_vtbl_ptr(vtbl_list, new_vtable_start, k);
219 }
220 }
221 }
222
223 // Closure for serializing initialization data out to a data area to be
224 // written to the shared file.
225
226 class WriteClosure : public SerializeClosure {
227 private:
228 intptr_t* top;
229 char* end;
230
231 inline void check_space() {
232 if ((char*)top + sizeof(intptr_t) > end) {
233 report_out_of_shared_space(SharedMiscData);
234 }
235 }
236
237 public:
238 WriteClosure(char* md_top, char* md_end) {
239 top = (intptr_t*)md_top;
240 end = md_end;
241 }
242
243 char* get_top() { return (char*)top; }
244
245 void do_ptr(void** p) {
246 check_space();
247 *top = (intptr_t)*p;
248 ++top;
249 }
250
251 void do_tag(int tag) {
252 check_space();
253 *top = (intptr_t)tag;
254 ++top;
255 }
256
257 void do_region(u_char* start, size_t size) {
258 if ((char*)top + size > end) {
259 report_out_of_shared_space(SharedMiscData);
260 }
261 assert((intptr_t)start % sizeof(intptr_t) == 0, "bad alignment");
262 assert(size % sizeof(intptr_t) == 0, "bad size");
263 do_tag((int)size);
264 while (size > 0) {
265 *top = *(intptr_t*)start;
266 ++top;
267 start += sizeof(intptr_t);
268 size -= sizeof(intptr_t);
269 }
270 }
271
272 bool reading() const { return false; }
273 };
274
275 // This is for dumping detailed statistics for the allocations
276 // in the shared spaces.
277 class DumpAllocClosure : public Metaspace::AllocRecordClosure {
278 public:
279
280 // Here's poor man's enum inheritance
281 #define SHAREDSPACE_OBJ_TYPES_DO(f) \
282 METASPACE_OBJ_TYPES_DO(f) \
283 f(SymbolHashentry) \
284 f(SymbolBucket) \
285 f(Other)
286
287 #define SHAREDSPACE_OBJ_TYPE_DECLARE(name) name ## Type,
288 #define SHAREDSPACE_OBJ_TYPE_NAME_CASE(name) case name ## Type: return #name;
289
290 enum Type {
291 // Types are MetaspaceObj::ClassType, MetaspaceObj::SymbolType, etc
292 SHAREDSPACE_OBJ_TYPES_DO(SHAREDSPACE_OBJ_TYPE_DECLARE)
293 _number_of_types
294 };
295
296 static const char * type_name(Type type) {
297 switch(type) {
298 SHAREDSPACE_OBJ_TYPES_DO(SHAREDSPACE_OBJ_TYPE_NAME_CASE)
299 default:
300 ShouldNotReachHere();
301 return NULL;
302 }
303 }
304
305 public:
306 enum {
307 RO = 0,
308 RW = 1
309 };
310
311 int _counts[2][_number_of_types];
312 int _bytes [2][_number_of_types];
313 int _which;
314
315 DumpAllocClosure() {
316 memset(_counts, 0, sizeof(_counts));
317 memset(_bytes, 0, sizeof(_bytes));
318 };
319
320 void iterate_metaspace(Metaspace* space, int which) {
321 assert(which == RO || which == RW, "sanity");
322 _which = which;
323 space->iterate(this);
324 }
325
326 virtual void doit(address ptr, MetaspaceObj::Type type, int byte_size) {
327 assert(int(type) >= 0 && type < MetaspaceObj::_number_of_types, "sanity");
328 _counts[_which][type] ++;
329 _bytes [_which][type] += byte_size;
330 }
331
332 void dump_stats(int ro_all, int rw_all, int md_all, int mc_all);
333 };
334
335 void DumpAllocClosure::dump_stats(int ro_all, int rw_all, int md_all, int mc_all) {
336 rw_all += (md_all + mc_all); // md and mc are all mapped Read/Write
337 int other_bytes = md_all + mc_all;
338
339 // Calculate size of data that was not allocated by Metaspace::allocate()
340 MetaspaceSharedStats *stats = MetaspaceShared::stats();
341
342 // symbols
343 _counts[RW][SymbolHashentryType] = stats->symbol.hashentry_count;
344 _bytes [RW][SymbolHashentryType] = stats->symbol.hashentry_bytes;
345 other_bytes -= stats->symbol.hashentry_bytes;
346
347 _counts[RW][SymbolBucketType] = stats->symbol.bucket_count;
348 _bytes [RW][SymbolBucketType] = stats->symbol.bucket_bytes;
349 other_bytes -= stats->symbol.bucket_bytes;
350
351 // TODO: count things like dictionary, vtable, etc
352 _bytes[RW][OtherType] = other_bytes;
353
354 // prevent divide-by-zero
355 if (ro_all < 1) {
356 ro_all = 1;
357 }
358 if (rw_all < 1) {
359 rw_all = 1;
360 }
361
362 int all_ro_count = 0;
363 int all_ro_bytes = 0;
364 int all_rw_count = 0;
365 int all_rw_bytes = 0;
366
367 // To make fmt_stats be a syntactic constant (for format warnings), use #define.
368 #define fmt_stats "%-20s: %8d %10d %5.1f | %8d %10d %5.1f | %8d %10d %5.1f"
369 const char *sep = "--------------------+---------------------------+---------------------------+--------------------------";
370 const char *hdr = " ro_cnt ro_bytes % | rw_cnt rw_bytes % | all_cnt all_bytes %";
371
372 tty->print_cr("Detailed metadata info (rw includes md and mc):");
373 tty->print_cr("%s", hdr);
374 tty->print_cr("%s", sep);
375 for (int type = 0; type < int(_number_of_types); type ++) {
376 const char *name = type_name((Type)type);
377 int ro_count = _counts[RO][type];
378 int ro_bytes = _bytes [RO][type];
379 int rw_count = _counts[RW][type];
380 int rw_bytes = _bytes [RW][type];
381 int count = ro_count + rw_count;
382 int bytes = ro_bytes + rw_bytes;
383
384 double ro_perc = 100.0 * double(ro_bytes) / double(ro_all);
385 double rw_perc = 100.0 * double(rw_bytes) / double(rw_all);
386 double perc = 100.0 * double(bytes) / double(ro_all + rw_all);
387
388 tty->print_cr(fmt_stats, name,
389 ro_count, ro_bytes, ro_perc,
390 rw_count, rw_bytes, rw_perc,
391 count, bytes, perc);
392
393 all_ro_count += ro_count;
394 all_ro_bytes += ro_bytes;
395 all_rw_count += rw_count;
396 all_rw_bytes += rw_bytes;
397 }
398
399 int all_count = all_ro_count + all_rw_count;
400 int all_bytes = all_ro_bytes + all_rw_bytes;
401
402 double all_ro_perc = 100.0 * double(all_ro_bytes) / double(ro_all);
403 double all_rw_perc = 100.0 * double(all_rw_bytes) / double(rw_all);
404 double all_perc = 100.0 * double(all_bytes) / double(ro_all + rw_all);
405
406 tty->print_cr("%s", sep);
407 tty->print_cr(fmt_stats, "Total",
408 all_ro_count, all_ro_bytes, all_ro_perc,
409 all_rw_count, all_rw_bytes, all_rw_perc,
410 all_count, all_bytes, all_perc);
411
412 assert(all_ro_bytes == ro_all, "everything should have been counted");
413 assert(all_rw_bytes == rw_all, "everything should have been counted");
414 #undef fmt_stats
415 }
416
417 // Populate the shared space.
418
419 class VM_PopulateDumpSharedSpace: public VM_Operation {
420 private:
421 ClassLoaderData* _loader_data;
422 GrowableArray<Klass*> *_class_promote_order;
423 VirtualSpace _md_vs;
424 VirtualSpace _mc_vs;
425
426 public:
427 VM_PopulateDumpSharedSpace(ClassLoaderData* loader_data,
428 GrowableArray<Klass*> *class_promote_order) :
429 _loader_data(loader_data) {
430
431 // Split up and initialize the misc code and data spaces
432 ReservedSpace* shared_rs = MetaspaceShared::shared_rs();
433 size_t metadata_size = SharedReadOnlySize + SharedReadWriteSize;
434 ReservedSpace shared_ro_rw = shared_rs->first_part(metadata_size);
435 ReservedSpace misc_section = shared_rs->last_part(metadata_size);
436
437 // Now split into misc sections.
438 ReservedSpace md_rs = misc_section.first_part(SharedMiscDataSize);
439 ReservedSpace mc_rs = misc_section.last_part(SharedMiscDataSize);
440 _md_vs.initialize(md_rs, SharedMiscDataSize);
441 _mc_vs.initialize(mc_rs, SharedMiscCodeSize);
442 _class_promote_order = class_promote_order;
443 }
444
445 VMOp_Type type() const { return VMOp_PopulateDumpSharedSpace; }
446 void doit(); // outline because gdb sucks
447
448 private:
449 void handle_misc_data_space_failure(bool success) {
450 if (!success) {
451 report_out_of_shared_space(SharedMiscData);
452 }
453 }
454 }; // class VM_PopulateDumpSharedSpace
455
456
457 void VM_PopulateDumpSharedSpace::doit() {
458 Thread* THREAD = VMThread::vm_thread();
459 NOT_PRODUCT(SystemDictionary::verify();)
460 // The following guarantee is meant to ensure that no loader constraints
461 // exist yet, since the constraints table is not shared. This becomes
462 // more important now that we don't re-initialize vtables/itables for
463 // shared classes at runtime, where constraints were previously created.
464 guarantee(SystemDictionary::constraints()->number_of_entries() == 0,
465 "loader constraints are not saved");
466 guarantee(SystemDictionary::placeholders()->number_of_entries() == 0,
467 "placeholders are not saved");
468 // Revisit and implement this if we prelink method handle call sites:
469 guarantee(SystemDictionary::invoke_method_table() == NULL ||
470 SystemDictionary::invoke_method_table()->number_of_entries() == 0,
471 "invoke method table is not saved");
472
473 // At this point, many classes have been loaded.
474 // Gather systemDictionary classes in a global array and do everything to
475 // that so we don't have to walk the SystemDictionary again.
476 _global_klass_objects = new GrowableArray<Klass*>(1000);
477 Universe::basic_type_classes_do(collect_classes);
478 SystemDictionary::classes_do(collect_classes);
479
480 tty->print_cr("Number of classes %d", _global_klass_objects->length());
481 {
482 int num_type_array = 0, num_obj_array = 0, num_inst = 0;
483 for (int i = 0; i < _global_klass_objects->length(); i++) {
484 Klass* k = _global_klass_objects->at(i);
485 if (k->oop_is_instance()) {
486 num_inst ++;
487 } else if (k->oop_is_objArray()) {
488 num_obj_array ++;
489 } else {
490 assert(k->oop_is_typeArray(), "sanity");
491 num_type_array ++;
492 }
493 }
494 tty->print_cr(" instance classes = %5d", num_inst);
495 tty->print_cr(" obj array classes = %5d", num_obj_array);
496 tty->print_cr(" type array classes = %5d", num_type_array);
497 }
498
499
500 // Ensure the ConstMethods won't be modified at run-time
501 tty->print("Updating ConstMethods ... ");
502 rewrite_nofast_bytecodes_and_calculate_fingerprints();
503 tty->print_cr("done. ");
504
505 // Remove all references outside the metadata
506 tty->print("Removing unshareable information ... ");
507 remove_unshareable_in_classes();
508 tty->print_cr("done. ");
509
510 // Set up the share data and shared code segments.
511 char* md_low = _md_vs.low();
512 char* md_top = md_low;
513 char* md_end = _md_vs.high();
514 char* mc_low = _mc_vs.low();
515 char* mc_top = mc_low;
516 char* mc_end = _mc_vs.high();
517
518 // Reserve space for the list of Klass*s whose vtables are used
519 // for patching others as needed.
520
521 void** vtbl_list = (void**)md_top;
522 int vtbl_list_size = MetaspaceShared::vtbl_list_size;
523 Universe::init_self_patching_vtbl_list(vtbl_list, vtbl_list_size);
524
525 md_top += vtbl_list_size * sizeof(void*);
526 void* vtable = md_top;
527
528 // Reserve space for a new dummy vtable for klass objects in the
529 // heap. Generate self-patching vtable entries.
530
531 MetaspaceShared::generate_vtable_methods(vtbl_list, &vtable,
532 &md_top, md_end,
533 &mc_top, mc_end);
534
535 // Reorder the system dictionary. (Moving the symbols affects
536 // how the hash table indices are calculated.)
537 // Not doing this either.
538
539 SystemDictionary::reorder_dictionary();
540
541 NOT_PRODUCT(SystemDictionary::verify();)
542
543 // Copy the the symbol table, and the system dictionary to the shared
544 // space in usable form. Copy the hashtable
545 // buckets first [read-write], then copy the linked lists of entries
546 // [read-only].
547
548 NOT_PRODUCT(SymbolTable::verify());
549 handle_misc_data_space_failure(SymbolTable::copy_compact_table(&md_top, md_end));
550
551 SystemDictionary::reverse();
552 SystemDictionary::copy_buckets(&md_top, md_end);
553
554 ClassLoader::verify();
555 ClassLoader::copy_package_info_buckets(&md_top, md_end);
556 ClassLoader::verify();
557
558 SystemDictionary::copy_table(&md_top, md_end);
559 ClassLoader::verify();
560 ClassLoader::copy_package_info_table(&md_top, md_end);
561 ClassLoader::verify();
562
563 // Write the other data to the output array.
564 WriteClosure wc(md_top, md_end);
565 MetaspaceShared::serialize(&wc);
566 md_top = wc.get_top();
567
568 // Print shared spaces all the time
569 // To make fmt_space be a syntactic constant (for format warnings), use #define.
570 #define fmt_space "%s space: %9d [ %4.1f%% of total] out of %9d bytes [%4.1f%% used] at " INTPTR_FORMAT
571 Metaspace* ro_space = _loader_data->ro_metaspace();
572 Metaspace* rw_space = _loader_data->rw_metaspace();
573
574 // Allocated size of each space (may not be all occupied)
575 const size_t ro_alloced = ro_space->capacity_bytes_slow(Metaspace::NonClassType);
576 const size_t rw_alloced = rw_space->capacity_bytes_slow(Metaspace::NonClassType);
577 const size_t md_alloced = md_end-md_low;
578 const size_t mc_alloced = mc_end-mc_low;
579 const size_t total_alloced = ro_alloced + rw_alloced + md_alloced + mc_alloced;
580
581 // Occupied size of each space.
582 const size_t ro_bytes = ro_space->used_bytes_slow(Metaspace::NonClassType);
583 const size_t rw_bytes = rw_space->used_bytes_slow(Metaspace::NonClassType);
584 const size_t md_bytes = size_t(md_top - md_low);
585 const size_t mc_bytes = size_t(mc_top - mc_low);
586
587 // Percent of total size
588 const size_t total_bytes = ro_bytes + rw_bytes + md_bytes + mc_bytes;
589 const double ro_t_perc = ro_bytes / double(total_bytes) * 100.0;
590 const double rw_t_perc = rw_bytes / double(total_bytes) * 100.0;
591 const double md_t_perc = md_bytes / double(total_bytes) * 100.0;
592 const double mc_t_perc = mc_bytes / double(total_bytes) * 100.0;
593
594 // Percent of fullness of each space
595 const double ro_u_perc = ro_bytes / double(ro_alloced) * 100.0;
596 const double rw_u_perc = rw_bytes / double(rw_alloced) * 100.0;
597 const double md_u_perc = md_bytes / double(md_alloced) * 100.0;
598 const double mc_u_perc = mc_bytes / double(mc_alloced) * 100.0;
599 const double total_u_perc = total_bytes / double(total_alloced) * 100.0;
600
601 tty->print_cr(fmt_space, "ro", ro_bytes, ro_t_perc, ro_alloced, ro_u_perc, ro_space->bottom());
602 tty->print_cr(fmt_space, "rw", rw_bytes, rw_t_perc, rw_alloced, rw_u_perc, rw_space->bottom());
603 tty->print_cr(fmt_space, "md", md_bytes, md_t_perc, md_alloced, md_u_perc, md_low);
604 tty->print_cr(fmt_space, "mc", mc_bytes, mc_t_perc, mc_alloced, mc_u_perc, mc_low);
605 tty->print_cr("total : %9d [100.0%% of total] out of %9d bytes [%4.1f%% used]",
606 total_bytes, total_alloced, total_u_perc);
607
608 // Update the vtable pointers in all of the Klass objects in the
609 // heap. They should point to newly generated vtable.
610 patch_klass_vtables(vtbl_list, vtable);
611
612 // dunno what this is for.
613 char* saved_vtbl = (char*)os::malloc(vtbl_list_size * sizeof(void*), mtClass);
614 memmove(saved_vtbl, vtbl_list, vtbl_list_size * sizeof(void*));
615 memset(vtbl_list, 0, vtbl_list_size * sizeof(void*));
616
617 // Create and write the archive file that maps the shared spaces.
618
619 FileMapInfo* mapinfo = new FileMapInfo();
620 mapinfo->populate_header(MetaspaceShared::max_alignment());
621
622 // Pass 1 - update file offsets in header.
623 mapinfo->write_header();
624 mapinfo->write_space(MetaspaceShared::ro, _loader_data->ro_metaspace(), true);
625 mapinfo->write_space(MetaspaceShared::rw, _loader_data->rw_metaspace(), false);
626 mapinfo->write_region(MetaspaceShared::md, _md_vs.low(),
627 pointer_delta(md_top, _md_vs.low(), sizeof(char)),
628 SharedMiscDataSize,
629 false, false);
630 mapinfo->write_region(MetaspaceShared::mc, _mc_vs.low(),
631 pointer_delta(mc_top, _mc_vs.low(), sizeof(char)),
632 SharedMiscCodeSize,
633 true, true);
634
635 // Pass 2 - write data.
636 mapinfo->open_for_write();
637 mapinfo->set_header_crc(mapinfo->compute_header_crc());
638 mapinfo->write_header();
639 mapinfo->write_space(MetaspaceShared::ro, _loader_data->ro_metaspace(), true);
640 mapinfo->write_space(MetaspaceShared::rw, _loader_data->rw_metaspace(), false);
641 mapinfo->write_region(MetaspaceShared::md, _md_vs.low(),
642 pointer_delta(md_top, _md_vs.low(), sizeof(char)),
643 SharedMiscDataSize,
644 false, false);
645 mapinfo->write_region(MetaspaceShared::mc, _mc_vs.low(),
646 pointer_delta(mc_top, _mc_vs.low(), sizeof(char)),
647 SharedMiscCodeSize,
648 true, true);
649 mapinfo->close();
650
651 memmove(vtbl_list, saved_vtbl, vtbl_list_size * sizeof(void*));
652
653 if (PrintSharedSpaces) {
654 DumpAllocClosure dac;
655 dac.iterate_metaspace(_loader_data->ro_metaspace(), DumpAllocClosure::RO);
656 dac.iterate_metaspace(_loader_data->rw_metaspace(), DumpAllocClosure::RW);
657
658 dac.dump_stats(int(ro_bytes), int(rw_bytes), int(md_bytes), int(mc_bytes));
659 }
660 #undef fmt_space
661 }
662
663
664 void MetaspaceShared::link_one_shared_class(Klass* obj, TRAPS) {
665 Klass* k = obj;
666 if (k->oop_is_instance()) {
667 InstanceKlass* ik = (InstanceKlass*) k;
668 // Link the class to cause the bytecodes to be rewritten and the
669 // cpcache to be created. Class verification is done according
670 // to -Xverify setting.
671 _link_classes_made_progress |= try_link_class(ik, THREAD);
672 guarantee(!HAS_PENDING_EXCEPTION, "exception in link_class");
673 }
674 }
675
676 void MetaspaceShared::check_one_shared_class(Klass* k) {
677 if (k->oop_is_instance() && InstanceKlass::cast(k)->check_sharing_error_state()) {
678 _check_classes_made_progress = true;
679 }
680 }
681
682 void MetaspaceShared::link_and_cleanup_shared_classes(TRAPS) {
683 // We need to iterate because verification may cause additional classes
684 // to be loaded.
685 do {
686 _link_classes_made_progress = false;
687 SystemDictionary::classes_do(link_one_shared_class, THREAD);
688 guarantee(!HAS_PENDING_EXCEPTION, "exception in link_class");
689 } while (_link_classes_made_progress);
690
691 if (_has_error_classes) {
692 // Mark all classes whose super class or interfaces failed verification.
693 do {
694 // Not completely sure if we need to do this iteratively. Anyway,
695 // we should come here only if there are unverifiable classes, which
696 // shouldn't happen in normal cases. So better safe than sorry.
697 _check_classes_made_progress = false;
698 SystemDictionary::classes_do(check_one_shared_class);
699 } while (_check_classes_made_progress);
700
701 if (IgnoreUnverifiableClassesDuringDump) {
702 // This is useful when running JCK or SQE tests. You should not
703 // enable this when running real apps.
704 SystemDictionary::remove_classes_in_error_state();
705 } else {
706 tty->print_cr("Please remove the unverifiable classes from your class list and try again");
707 exit(1);
708 }
709 }
710 }
711
712 void MetaspaceShared::prepare_for_dumping() {
713 ClassLoader::initialize_shared_path();
714 FileMapInfo::allocate_classpath_entry_table();
715 }
716
717 // Preload classes from a list, populate the shared spaces and dump to a
718 // file.
719 void MetaspaceShared::preload_and_dump(TRAPS) {
720 TraceTime timer("Dump Shared Spaces", TraceStartupTime);
721 ResourceMark rm;
722
723 tty->print_cr("Allocated shared space: %d bytes at " PTR_FORMAT,
724 MetaspaceShared::shared_rs()->size(),
725 MetaspaceShared::shared_rs()->base());
726
727 // Preload classes to be shared.
728 // Should use some os:: method rather than fopen() here. aB.
729 const char* class_list_path;
730 if (SharedClassListFile == NULL) {
731 // Construct the path to the class list (in jre/lib)
732 // Walk up two directories from the location of the VM and
733 // optionally tack on "lib" (depending on platform)
734 char class_list_path_str[JVM_MAXPATHLEN];
735 os::jvm_path(class_list_path_str, sizeof(class_list_path_str));
736 for (int i = 0; i < 3; i++) {
737 char *end = strrchr(class_list_path_str, *os::file_separator());
738 if (end != NULL) *end = '\0';
739 }
740 int class_list_path_len = (int)strlen(class_list_path_str);
741 if (class_list_path_len >= 3) {
742 if (strcmp(class_list_path_str + class_list_path_len - 3, "lib") != 0) {
743 if (class_list_path_len < JVM_MAXPATHLEN - 4) {
744 jio_snprintf(class_list_path_str + class_list_path_len,
745 sizeof(class_list_path_str) - class_list_path_len,
746 "%slib", os::file_separator());
747 class_list_path_len += 4;
748 }
749 }
750 }
751 if (class_list_path_len < JVM_MAXPATHLEN - 10) {
752 jio_snprintf(class_list_path_str + class_list_path_len,
753 sizeof(class_list_path_str) - class_list_path_len,
754 "%sclasslist", os::file_separator());
755 }
756 class_list_path = class_list_path_str;
757 } else {
758 class_list_path = SharedClassListFile;
759 }
760
761 int class_count = 0;
762 GrowableArray<Klass*>* class_promote_order = new GrowableArray<Klass*>();
763
764 // sun.io.Converters
765 static const char obj_array_sig[] = "[[Ljava/lang/Object;";
766 SymbolTable::new_permanent_symbol(obj_array_sig, THREAD);
767
768 // java.util.HashMap
769 static const char map_entry_array_sig[] = "[Ljava/util/Map$Entry;";
770 SymbolTable::new_permanent_symbol(map_entry_array_sig, THREAD);
771
772 tty->print_cr("Loading classes to share ...");
773 _has_error_classes = false;
774 class_count += preload_and_dump(class_list_path, class_promote_order,
775 THREAD);
776 if (ExtraSharedClassListFile) {
777 class_count += preload_and_dump(ExtraSharedClassListFile, class_promote_order,
778 THREAD);
779 }
780 tty->print_cr("Loading classes to share: done.");
781
782 if (PrintSharedSpaces) {
783 tty->print_cr("Shared spaces: preloaded %d classes", class_count);
784 }
785
786 // Rewrite and link classes
787 tty->print_cr("Rewriting and linking classes ...");
788
789 // Link any classes which got missed. This would happen if we have loaded classes that
790 // were not explicitly specified in the classlist. E.g., if an interface implemented by class K
791 // fails verification, all other interfaces that were not specified in the classlist but
792 // are implemented by K are not verified.
793 link_and_cleanup_shared_classes(CATCH);
794 tty->print_cr("Rewriting and linking classes: done");
795
796 // Create and dump the shared spaces. Everything so far is loaded
797 // with the null class loader.
798 ClassLoaderData* loader_data = ClassLoaderData::the_null_class_loader_data();
799 VM_PopulateDumpSharedSpace op(loader_data, class_promote_order);
800 VMThread::execute(&op);
801
802 // Since various initialization steps have been undone by this process,
803 // it is not reasonable to continue running a java process.
804 exit(0);
805 }
806
807 int MetaspaceShared::preload_and_dump(const char * class_list_path,
808 GrowableArray<Klass*>* class_promote_order,
809 TRAPS) {
810 FILE* file = fopen(class_list_path, "r");
811 char class_name[256];
812 int class_count = 0;
813
814 if (file != NULL) {
815 while ((fgets(class_name, sizeof class_name, file)) != NULL) {
816 if (*class_name == '#') { // comment
817 continue;
818 }
819 // Remove trailing newline
820 size_t name_len = strlen(class_name);
821 if (class_name[name_len-1] == '\n') {
822 class_name[name_len-1] = '\0';
823 }
824
825 // Got a class name - load it.
826 TempNewSymbol class_name_symbol = SymbolTable::new_permanent_symbol(class_name, THREAD);
827 guarantee(!HAS_PENDING_EXCEPTION, "Exception creating a symbol.");
828 Klass* klass = SystemDictionary::resolve_or_null(class_name_symbol,
829 THREAD);
830 CLEAR_PENDING_EXCEPTION;
831 if (klass != NULL) {
832 if (PrintSharedSpaces && Verbose && WizardMode) {
833 tty->print_cr("Shared spaces preloaded: %s", class_name);
834 }
835
836 InstanceKlass* ik = InstanceKlass::cast(klass);
837
838 // Should be class load order as per -XX:+TraceClassLoadingPreorder
839 class_promote_order->append(ik);
840
841 // Link the class to cause the bytecodes to be rewritten and the
842 // cpcache to be created. The linking is done as soon as classes
843 // are loaded in order that the related data structures (klass and
844 // cpCache) are located together.
845 try_link_class(ik, THREAD);
846 guarantee(!HAS_PENDING_EXCEPTION, "exception in link_class");
847
848 class_count++;
849 } else {
850 //tty->print_cr("Preload failed: %s", class_name);
851 }
852 }
853 fclose(file);
854 } else {
855 char errmsg[JVM_MAXPATHLEN];
856 os::lasterror(errmsg, JVM_MAXPATHLEN);
857 tty->print_cr("Loading classlist failed: %s", errmsg);
858 exit(1);
859 }
860
861 return class_count;
862 }
863
864 // Returns true if the class's status has changed
865 bool MetaspaceShared::try_link_class(InstanceKlass* ik, TRAPS) {
866 assert(DumpSharedSpaces, "should only be called during dumping");
867 if (ik->init_state() < InstanceKlass::linked) {
868 bool saved = BytecodeVerificationLocal;
869 if (!SharedClassUtil::is_shared_boot_class(ik)) {
870 // The verification decision is based on BytecodeVerificationRemote
871 // for non-system classes. Since we are using the NULL classloader
872 // to load non-system classes during dumping, we need to temporarily
873 // change BytecodeVerificationLocal to be the same as
874 // BytecodeVerificationRemote. Note this can cause the parent system
875 // classes also being verified. The extra overhead is acceptable during
876 // dumping.
877 BytecodeVerificationLocal = BytecodeVerificationRemote;
878 }
879 ik->link_class(THREAD);
880 if (HAS_PENDING_EXCEPTION) {
881 ResourceMark rm;
882 tty->print_cr("Preload Warning: Verification failed for %s",
883 ik->external_name());
884 CLEAR_PENDING_EXCEPTION;
885 ik->set_in_error_state();
886 _has_error_classes = true;
887 }
888 BytecodeVerificationLocal = saved;
889 return true;
890 } else {
891 return false;
892 }
893 }
894
895 // Closure for serializing initialization data in from a data area
896 // (ptr_array) read from the shared file.
897
898 class ReadClosure : public SerializeClosure {
899 private:
900 intptr_t** _ptr_array;
901
902 inline intptr_t nextPtr() {
903 return *(*_ptr_array)++;
904 }
905
906 public:
907 ReadClosure(intptr_t** ptr_array) { _ptr_array = ptr_array; }
908
909 void do_ptr(void** p) {
910 assert(*p == NULL, "initializing previous initialized pointer.");
911 intptr_t obj = nextPtr();
912 assert((intptr_t)obj >= 0 || (intptr_t)obj < -100,
913 "hit tag while initializing ptrs.");
914 *p = (void*)obj;
915 }
916
917 void do_tag(int tag) {
918 int old_tag;
919 old_tag = (int)(intptr_t)nextPtr();
920 // do_int(&old_tag);
921 assert(tag == old_tag, "old tag doesn't match");
922 FileMapInfo::assert_mark(tag == old_tag);
923 }
924
925 void do_region(u_char* start, size_t size) {
926 assert((intptr_t)start % sizeof(intptr_t) == 0, "bad alignment");
927 assert(size % sizeof(intptr_t) == 0, "bad size");
928 do_tag((int)size);
929 while (size > 0) {
930 *(intptr_t*)start = nextPtr();
931 start += sizeof(intptr_t);
932 size -= sizeof(intptr_t);
933 }
934 }
935
936 bool reading() const { return true; }
937 };
938
939 // Return true if given address is in the mapped shared space.
940 bool MetaspaceShared::is_in_shared_space(const void* p) {
941 return UseSharedSpaces && FileMapInfo::current_info()->is_in_shared_space(p);
942 }
943
944 void MetaspaceShared::print_shared_spaces() {
945 if (UseSharedSpaces) {
946 FileMapInfo::current_info()->print_shared_spaces();
947 }
948 }
949
950
951 // Map shared spaces at requested addresses and return if succeeded.
952 // Need to keep the bounds of the ro and rw space for the Metaspace::contains
953 // call, or is_in_shared_space.
954 bool MetaspaceShared::map_shared_spaces(FileMapInfo* mapinfo) {
955 size_t image_alignment = mapinfo->alignment();
956
957 #ifndef _WINDOWS
958 // Map in the shared memory and then map the regions on top of it.
959 // On Windows, don't map the memory here because it will cause the
960 // mappings of the regions to fail.
961 ReservedSpace shared_rs = mapinfo->reserve_shared_memory();
962 if (!shared_rs.is_reserved()) return false;
963 #endif
964
965 assert(!DumpSharedSpaces, "Should not be called with DumpSharedSpaces");
966
967 char* _ro_base = NULL;
968 char* _rw_base = NULL;
969 char* _md_base = NULL;
970 char* _mc_base = NULL;
971
972 // Map each shared region
973 if ((_ro_base = mapinfo->map_region(ro)) != NULL &&
974 mapinfo->verify_region_checksum(ro) &&
975 (_rw_base = mapinfo->map_region(rw)) != NULL &&
976 mapinfo->verify_region_checksum(rw) &&
977 (_md_base = mapinfo->map_region(md)) != NULL &&
978 mapinfo->verify_region_checksum(md) &&
979 (_mc_base = mapinfo->map_region(mc)) != NULL &&
980 mapinfo->verify_region_checksum(mc) &&
981 (image_alignment == (size_t)max_alignment()) &&
982 mapinfo->validate_classpath_entry_table()) {
983 // Success (no need to do anything)
984 return true;
985 } else {
986 // If there was a failure in mapping any of the spaces, unmap the ones
987 // that succeeded
988 if (_ro_base != NULL) mapinfo->unmap_region(ro);
989 if (_rw_base != NULL) mapinfo->unmap_region(rw);
990 if (_md_base != NULL) mapinfo->unmap_region(md);
991 if (_mc_base != NULL) mapinfo->unmap_region(mc);
992 #ifndef _WINDOWS
993 // Release the entire mapped region
994 shared_rs.release();
995 #endif
996 // If -Xshare:on is specified, print out the error message and exit VM,
997 // otherwise, set UseSharedSpaces to false and continue.
998 if (RequireSharedSpaces || PrintSharedArchiveAndExit) {
999 vm_exit_during_initialization("Unable to use shared archive.", "Failed map_region for using -Xshare:on.");
1000 } else {
1001 FLAG_SET_DEFAULT(UseSharedSpaces, false);
1002 }
1003 return false;
1004 }
1005 }
1006
1007 // Read the miscellaneous data from the shared file, and
1008 // serialize it out to its various destinations.
1009
1010 void MetaspaceShared::initialize_shared_spaces() {
1011 FileMapInfo *mapinfo = FileMapInfo::current_info();
1012
1013 char* buffer = mapinfo->region_base(md);
1014
1015 // Skip over (reserve space for) a list of addresses of C++ vtables
1016 // for Klass objects. They get filled in later.
1017
1018 void** vtbl_list = (void**)buffer;
1019 buffer += MetaspaceShared::vtbl_list_size * sizeof(void*);
1020 Universe::init_self_patching_vtbl_list(vtbl_list, vtbl_list_size);
1021
1022 // Skip over (reserve space for) dummy C++ vtables Klass objects.
1023 // They are used as is.
1024
1025 intptr_t vtable_size = *(intptr_t*)buffer;
1026 buffer += sizeof(intptr_t);
1027 buffer += vtable_size;
1028
1029 // Create the shared symbol table using the bucket array at this spot in the
1030 // misc data space. (Todo: move this to read-only space. Currently
1031 // this is mapped copy-on-write but will never be written into).
1032
1033 buffer = (char*)SymbolTable::init_shared_table(buffer);
1034 SymbolTable::create_table();
1035
1036 // Create the shared dictionary using the bucket array at this spot in
1037 // the misc data space. Since the shared dictionary table is never
1038 // modified, this region (of mapped pages) will be (effectively, if
1039 // not explicitly) read-only.
1040
1041 int sharedDictionaryLen = *(intptr_t*)buffer;
1042 buffer += sizeof(intptr_t);
1043 int number_of_entries = *(intptr_t*)buffer;
1044 buffer += sizeof(intptr_t);
1045 SystemDictionary::set_shared_dictionary((HashtableBucket<mtClass>*)buffer,
1046 sharedDictionaryLen,
1047 number_of_entries);
1048 buffer += sharedDictionaryLen;
1049
1050 // Create the package info table using the bucket array at this spot in
1051 // the misc data space. Since the package info table is never
1052 // modified, this region (of mapped pages) will be (effectively, if
1053 // not explicitly) read-only.
1054
1055 int pkgInfoLen = *(intptr_t*)buffer;
1056 buffer += sizeof(intptr_t);
1057 number_of_entries = *(intptr_t*)buffer;
1058 buffer += sizeof(intptr_t);
1059 ClassLoader::create_package_info_table((HashtableBucket<mtClass>*)buffer, pkgInfoLen,
1060 number_of_entries);
1061 buffer += pkgInfoLen;
1062 ClassLoader::verify();
1063
1064 // The following data in the shared misc data region are the linked
1065 // list elements (HashtableEntry objects) for the shared dictionary
1066 // and package info table.
1067
1068 int len = *(intptr_t*)buffer; // skip over shared dictionary entries
1069 buffer += sizeof(intptr_t);
1070 buffer += len;
1071
1072 len = *(intptr_t*)buffer; // skip over package info table entries
1073 buffer += sizeof(intptr_t);
1074 buffer += len;
1075
1076 len = *(intptr_t*)buffer; // skip over package info table char[] arrays.
1077 buffer += sizeof(intptr_t);
1078 buffer += len;
1079
1080 intptr_t* array = (intptr_t*)buffer;
1081 ReadClosure rc(&array);
1082 serialize(&rc);
1083
1084 // Close the mapinfo file
1085 mapinfo->close();
1086
1087 if (PrintSharedArchiveAndExit) {
1088 if (PrintSharedDictionary) {
1089 tty->print_cr("\nShared classes:\n");
1090 SystemDictionary::print_shared(false);
1091 }
1092 if (_archive_loading_failed) {
1093 tty->print_cr("archive is invalid");
1094 vm_exit(1);
1095 } else {
1096 tty->print_cr("archive is valid");
1097 vm_exit(0);
1098 }
1099 }
1100 }
1101
1102 // JVM/TI RedefineClasses() support:
1103 bool MetaspaceShared::remap_shared_readonly_as_readwrite() {
1104 assert(SafepointSynchronize::is_at_safepoint(), "must be at safepoint");
1105
1106 if (UseSharedSpaces) {
1107 // remap the shared readonly space to shared readwrite, private
1108 FileMapInfo* mapinfo = FileMapInfo::current_info();
1109 if (!mapinfo->remap_shared_readonly_as_readwrite()) {
1110 return false;
1111 }
1112 }
1113 return true;
1114 }
1115
1116 int MetaspaceShared::count_class(const char* classlist_file) {
1117 if (classlist_file == NULL) {
1118 return 0;
1119 }
1120 char class_name[256];
1121 int class_count = 0;
1122 FILE* file = fopen(classlist_file, "r");
1123 if (file != NULL) {
1124 while ((fgets(class_name, sizeof class_name, file)) != NULL) {
1125 if (*class_name == '#') { // comment
1126 continue;
1127 }
1128 class_count++;
1129 }
1130 fclose(file);
1131 } else {
1132 char errmsg[JVM_MAXPATHLEN];
1133 os::lasterror(errmsg, JVM_MAXPATHLEN);
1134 tty->print_cr("Loading classlist failed: %s", errmsg);
1135 exit(1);
1136 }
1137
1138 return class_count;
1139 }
1140
1141 // the sizes are good for typical large applications that have a lot of shared
1142 // classes
1143 void MetaspaceShared::estimate_regions_size() {
1144 int class_count = count_class(SharedClassListFile);
1145 class_count += count_class(ExtraSharedClassListFile);
1146
1147 if (class_count > LargeThresholdClassCount) {
1148 if (class_count < HugeThresholdClassCount) {
1149 SET_ESTIMATED_SIZE(Large, ReadOnly);
1150 SET_ESTIMATED_SIZE(Large, ReadWrite);
1151 SET_ESTIMATED_SIZE(Large, MiscData);
1152 SET_ESTIMATED_SIZE(Large, MiscCode);
1153 } else {
1154 SET_ESTIMATED_SIZE(Huge, ReadOnly);
1155 SET_ESTIMATED_SIZE(Huge, ReadWrite);
1156 SET_ESTIMATED_SIZE(Huge, MiscData);
1157 SET_ESTIMATED_SIZE(Huge, MiscCode);
1158 }
1159 }
1160 }