1 /*
2 * Copyright (c) 2012, 2016, 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/classListParser.hpp"
27 #include "classfile/classLoaderExt.hpp"
28 #include "classfile/dictionary.hpp"
29 #include "classfile/loaderConstraints.hpp"
30 #include "classfile/placeholders.hpp"
31 #include "classfile/sharedClassUtil.hpp"
32 #include "classfile/symbolTable.hpp"
33 #include "classfile/systemDictionary.hpp"
34 #include "code/codeCache.hpp"
35 #include "gc/shared/gcLocker.hpp"
36 #include "interpreter/bytecodeStream.hpp"
37 #include "interpreter/bytecodes.hpp"
38 #include "memory/filemap.hpp"
39 #include "memory/metaspace.hpp"
40 #include "memory/metaspaceShared.hpp"
41 #include "memory/resourceArea.hpp"
42 #include "oops/objArrayOop.hpp"
43 #include "oops/oop.inline.hpp"
44 #include "runtime/logTimer.hpp"
45 #include "runtime/os.hpp"
46 #include "runtime/signature.hpp"
47 #include "runtime/vmThread.hpp"
48 #include "runtime/vm_operations.hpp"
49 #include "utilities/defaultStream.hpp"
50 #include "utilities/hashtable.inline.hpp"
51
52 int MetaspaceShared::_max_alignment = 0;
53
54 ReservedSpace* MetaspaceShared::_shared_rs = NULL;
55
56 MetaspaceSharedStats MetaspaceShared::_stats;
57
58 bool MetaspaceShared::_link_classes_made_progress;
59 bool MetaspaceShared::_check_classes_made_progress;
60 bool MetaspaceShared::_has_error_classes;
61 bool MetaspaceShared::_archive_loading_failed = false;
62 SharedMiscRegion MetaspaceShared::_mc;
63 SharedMiscRegion MetaspaceShared::_md;
64
65 void SharedMiscRegion::initialize(ReservedSpace rs, size_t committed_byte_size, SharedSpaceType space_type) {
66 _vs.initialize(rs, committed_byte_size);
67 _alloc_top = _vs.low();
68 _space_type = space_type;
69 }
70
71 // NOT thread-safe, but this is called during dump time in single-threaded mode.
72 char* SharedMiscRegion::alloc(size_t num_bytes) {
73 assert(DumpSharedSpaces, "dump time only");
74 size_t alignment = sizeof(char*);
75 num_bytes = align_size_up(num_bytes, alignment);
76 _alloc_top = (char*)align_ptr_up(_alloc_top, alignment);
77 if (_alloc_top + num_bytes > _vs.high()) {
78 report_out_of_shared_space(_space_type);
79 }
80
81 char* p = _alloc_top;
82 _alloc_top += num_bytes;
83
84 memset(p, 0, num_bytes);
85 return p;
86 }
87
88 void MetaspaceShared::initialize_shared_rs(ReservedSpace* rs) {
89 assert(DumpSharedSpaces, "dump time only");
90 _shared_rs = rs;
91
92 // Split up and initialize the misc code and data spaces
93 size_t metadata_size = SharedReadOnlySize + SharedReadWriteSize;
94 ReservedSpace shared_ro_rw = _shared_rs->first_part(metadata_size);
95 ReservedSpace misc_section = _shared_rs->last_part(metadata_size);
96
97 // Now split into misc sections.
98 ReservedSpace md_rs = misc_section.first_part(SharedMiscDataSize);
99 ReservedSpace mc_rs = misc_section.last_part(SharedMiscDataSize);
100 _md.initialize(md_rs, SharedMiscDataSize, SharedMiscData);
101 _mc.initialize(mc_rs, SharedMiscCodeSize, SharedMiscData);
102 }
103
104 // Read/write a data stream for restoring/preserving metadata pointers and
105 // miscellaneous data from/to the shared archive file.
106
107 void MetaspaceShared::serialize(SerializeClosure* soc) {
108 int tag = 0;
109 soc->do_tag(--tag);
110
111 // Verify the sizes of various metadata in the system.
112 soc->do_tag(sizeof(Method));
113 soc->do_tag(sizeof(ConstMethod));
114 soc->do_tag(arrayOopDesc::base_offset_in_bytes(T_BYTE));
115 soc->do_tag(sizeof(ConstantPool));
116 soc->do_tag(sizeof(ConstantPoolCache));
117 soc->do_tag(objArrayOopDesc::base_offset_in_bytes());
118 soc->do_tag(typeArrayOopDesc::base_offset_in_bytes(T_BYTE));
119 soc->do_tag(sizeof(Symbol));
120
121 // Dump/restore miscellaneous metadata.
122 Universe::serialize(soc, true);
123 soc->do_tag(--tag);
124
125 // Dump/restore references to commonly used names and signatures.
126 vmSymbols::serialize(soc);
127 soc->do_tag(--tag);
128
129 soc->do_tag(666);
130 }
131
132
133 // CDS code for dumping shared archive.
134
135 // Global object for holding classes that have been loaded. Since this
136 // is run at a safepoint just before exit, this is the entire set of classes.
137 static GrowableArray<Klass*>* _global_klass_objects;
138 static void collect_classes(Klass* k) {
139 _global_klass_objects->append_if_missing(k);
140 if (k->is_instance_klass()) {
141 // Add in the array classes too
142 InstanceKlass* ik = InstanceKlass::cast(k);
143 ik->array_klasses_do(collect_classes);
144 }
145 }
146
147 static void collect_classes2(Klass* k, ClassLoaderData* class_data) {
148 collect_classes(k);
149 }
150
151 static void remove_unshareable_in_classes() {
152 for (int i = 0; i < _global_klass_objects->length(); i++) {
153 Klass* k = _global_klass_objects->at(i);
154 k->remove_unshareable_info();
155 }
156 }
157
158 static void rewrite_nofast_bytecode(Method* method) {
159 RawBytecodeStream bcs(method);
160 while (!bcs.is_last_bytecode()) {
161 Bytecodes::Code opcode = bcs.raw_next();
162 switch (opcode) {
163 case Bytecodes::_getfield: *bcs.bcp() = Bytecodes::_nofast_getfield; break;
164 case Bytecodes::_putfield: *bcs.bcp() = Bytecodes::_nofast_putfield; break;
165 case Bytecodes::_aload_0: *bcs.bcp() = Bytecodes::_nofast_aload_0; break;
166 case Bytecodes::_iload: *bcs.bcp() = Bytecodes::_nofast_iload; break;
167 default: break;
168 }
169 }
170 }
171
172 // Walk all methods in the class list to ensure that they won't be modified at
173 // run time. This includes:
174 // [1] Rewrite all bytecodes as needed, so that the ConstMethod* will not be modified
175 // at run time by RewriteBytecodes/RewriteFrequentPairs
176 // [2] Assign a fingerprint, so one doesn't need to be assigned at run-time.
177 static void rewrite_nofast_bytecodes_and_calculate_fingerprints() {
178 for (int i = 0; i < _global_klass_objects->length(); i++) {
179 Klass* k = _global_klass_objects->at(i);
180 if (k->is_instance_klass()) {
181 InstanceKlass* ik = InstanceKlass::cast(k);
182 for (int i = 0; i < ik->methods()->length(); i++) {
183 Method* m = ik->methods()->at(i);
184 rewrite_nofast_bytecode(m);
185 Fingerprinter fp(m);
186 // The side effect of this call sets method's fingerprint field.
187 fp.fingerprint();
188 }
189 }
190 }
191 }
192
193 // Patch C++ vtable pointer in metadata.
194
195 // Klass and other metadata objects contain references to c++ vtables in the
196 // JVM library.
197 // Fix them to point to our constructed vtables. However, don't iterate
198 // across the space while doing this, as that causes the vtables to be
199 // patched, undoing our useful work. Instead, iterate to make a list,
200 // then use the list to do the fixing.
201 //
202 // Our constructed vtables:
203 // Dump time:
204 // 1. init_self_patching_vtbl_list: table of pointers to current virtual method addrs
205 // 2. generate_vtable_methods: create jump table, appended to above vtbl_list
206 // 3. patch_klass_vtables: for Klass list, patch the vtable entry in klass and
207 // associated metadata to point to jump table rather than to current vtbl
208 // Table layout: NOTE FIXED SIZE
209 // 1. vtbl pointers
210 // 2. #Klass X #virtual methods per Klass
211 // 1 entry for each, in the order:
212 // Klass1:method1 entry, Klass1:method2 entry, ... Klass1:method<num_virtuals> entry
213 // Klass2:method1 entry, Klass2:method2 entry, ... Klass2:method<num_virtuals> entry
214 // ...
215 // Klass<vtbl_list_size>:method1 entry, Klass<vtbl_list_size>:method2 entry,
216 // ... Klass<vtbl_list_size>:method<num_virtuals> entry
217 // Sample entry: (Sparc):
218 // save(sp, -256, sp)
219 // ba,pt common_code
220 // mov XXX, %L0 %L0 gets: Klass index <<8 + method index (note: max method index 255)
221 //
222 // Restore time:
223 // 1. initialize_shared_space: reserve space for table
224 // 2. init_self_patching_vtbl_list: update pointers to NEW virtual method addrs in text
225 //
226 // Execution time:
227 // First virtual method call for any object of these metadata types:
228 // 1. object->klass
229 // 2. vtable entry for that klass points to the jump table entries
230 // 3. branches to common_code with %O0/klass, %L0: Klass index <<8 + method index
231 // 4. common_code:
232 // Get address of new vtbl pointer for this Klass from updated table
233 // Update new vtbl pointer in the Klass: future virtual calls go direct
234 // Jump to method, using new vtbl pointer and method index
235
236
237 static void* find_matching_vtbl_ptr(void** vtbl_list, void* new_vtable_start, void* obj) {
238 void* old_vtbl_ptr = *(void**)obj;
239 for (int i = 0; i < MetaspaceShared::vtbl_list_size; i++) {
240 if (vtbl_list[i] == old_vtbl_ptr) {
241 return (void**)new_vtable_start + i * MetaspaceShared::num_virtuals;
242 }
243 }
244 ShouldNotReachHere();
245 return NULL;
246 }
247
248 // Assumes the vtable is in first slot in object.
249 static void patch_klass_vtables(void** vtbl_list, void* new_vtable_start) {
250 int n = _global_klass_objects->length();
251 for (int i = 0; i < n; i++) {
252 Klass* obj = _global_klass_objects->at(i);
253 // Note is_instance_klass() is a virtual call in debug. After patching vtables
254 // all virtual calls on the dummy vtables will restore the original!
255 if (obj->is_instance_klass()) {
256 InstanceKlass* ik = InstanceKlass::cast(obj);
257 *(void**)ik = find_matching_vtbl_ptr(vtbl_list, new_vtable_start, ik);
258 ConstantPool* cp = ik->constants();
259 *(void**)cp = find_matching_vtbl_ptr(vtbl_list, new_vtable_start, cp);
260 for (int j = 0; j < ik->methods()->length(); j++) {
261 Method* m = ik->methods()->at(j);
262 *(void**)m = find_matching_vtbl_ptr(vtbl_list, new_vtable_start, m);
263 }
264 } else {
265 // Array klasses
266 Klass* k = obj;
267 *(void**)k = find_matching_vtbl_ptr(vtbl_list, new_vtable_start, k);
268 }
269 }
270 }
271
272 // Closure for serializing initialization data out to a data area to be
273 // written to the shared file.
274
275 class WriteClosure : public SerializeClosure {
276 private:
277 intptr_t* top;
278 char* end;
279
280 inline void check_space() {
281 if ((char*)top + sizeof(intptr_t) > end) {
282 report_out_of_shared_space(SharedMiscData);
283 }
284 }
285
286 public:
287 WriteClosure(char* md_top, char* md_end) {
288 top = (intptr_t*)md_top;
289 end = md_end;
290 }
291
292 char* get_top() { return (char*)top; }
293
294 void do_ptr(void** p) {
295 check_space();
296 *top = (intptr_t)*p;
297 ++top;
298 }
299
300 void do_tag(int tag) {
301 check_space();
302 *top = (intptr_t)tag;
303 ++top;
304 }
305
306 void do_region(u_char* start, size_t size) {
307 if ((char*)top + size > end) {
308 report_out_of_shared_space(SharedMiscData);
309 }
310 assert((intptr_t)start % sizeof(intptr_t) == 0, "bad alignment");
311 assert(size % sizeof(intptr_t) == 0, "bad size");
312 do_tag((int)size);
313 while (size > 0) {
314 *top = *(intptr_t*)start;
315 ++top;
316 start += sizeof(intptr_t);
317 size -= sizeof(intptr_t);
318 }
319 }
320
321 bool reading() const { return false; }
322 };
323
324 // This is for dumping detailed statistics for the allocations
325 // in the shared spaces.
326 class DumpAllocClosure : public Metaspace::AllocRecordClosure {
327 public:
328
329 // Here's poor man's enum inheritance
330 #define SHAREDSPACE_OBJ_TYPES_DO(f) \
331 METASPACE_OBJ_TYPES_DO(f) \
332 f(SymbolHashentry) \
333 f(SymbolBucket) \
334 f(Other)
335
336 #define SHAREDSPACE_OBJ_TYPE_DECLARE(name) name ## Type,
337 #define SHAREDSPACE_OBJ_TYPE_NAME_CASE(name) case name ## Type: return #name;
338
339 enum Type {
340 // Types are MetaspaceObj::ClassType, MetaspaceObj::SymbolType, etc
341 SHAREDSPACE_OBJ_TYPES_DO(SHAREDSPACE_OBJ_TYPE_DECLARE)
342 _number_of_types
343 };
344
345 static const char * type_name(Type type) {
346 switch(type) {
347 SHAREDSPACE_OBJ_TYPES_DO(SHAREDSPACE_OBJ_TYPE_NAME_CASE)
348 default:
349 ShouldNotReachHere();
350 return NULL;
351 }
352 }
353
354 public:
355 enum {
356 RO = 0,
357 RW = 1
358 };
359
360 int _counts[2][_number_of_types];
361 int _bytes [2][_number_of_types];
362 int _which;
363
364 DumpAllocClosure() {
365 memset(_counts, 0, sizeof(_counts));
366 memset(_bytes, 0, sizeof(_bytes));
367 };
368
369 void iterate_metaspace(Metaspace* space, int which) {
370 assert(which == RO || which == RW, "sanity");
371 _which = which;
372 space->iterate(this);
373 }
374
375 virtual void doit(address ptr, MetaspaceObj::Type type, int byte_size) {
376 assert(int(type) >= 0 && type < MetaspaceObj::_number_of_types, "sanity");
377 _counts[_which][type] ++;
378 _bytes [_which][type] += byte_size;
379 }
380
381 void dump_stats(int ro_all, int rw_all, int md_all, int mc_all);
382 };
383
384 void DumpAllocClosure::dump_stats(int ro_all, int rw_all, int md_all, int mc_all) {
385 rw_all += (md_all + mc_all); // md and mc are all mapped Read/Write
386 int other_bytes = md_all + mc_all;
387
388 // Calculate size of data that was not allocated by Metaspace::allocate()
389 MetaspaceSharedStats *stats = MetaspaceShared::stats();
390
391 // symbols
392 _counts[RW][SymbolHashentryType] = stats->symbol.hashentry_count;
393 _bytes [RW][SymbolHashentryType] = stats->symbol.hashentry_bytes;
394 other_bytes -= stats->symbol.hashentry_bytes;
395
396 _counts[RW][SymbolBucketType] = stats->symbol.bucket_count;
397 _bytes [RW][SymbolBucketType] = stats->symbol.bucket_bytes;
398 other_bytes -= stats->symbol.bucket_bytes;
399
400 // TODO: count things like dictionary, vtable, etc
401 _bytes[RW][OtherType] = other_bytes;
402
403 // prevent divide-by-zero
404 if (ro_all < 1) {
405 ro_all = 1;
406 }
407 if (rw_all < 1) {
408 rw_all = 1;
409 }
410
411 int all_ro_count = 0;
412 int all_ro_bytes = 0;
413 int all_rw_count = 0;
414 int all_rw_bytes = 0;
415
416 // To make fmt_stats be a syntactic constant (for format warnings), use #define.
417 #define fmt_stats "%-20s: %8d %10d %5.1f | %8d %10d %5.1f | %8d %10d %5.1f"
418 const char *sep = "--------------------+---------------------------+---------------------------+--------------------------";
419 const char *hdr = " ro_cnt ro_bytes % | rw_cnt rw_bytes % | all_cnt all_bytes %";
420
421 tty->print_cr("Detailed metadata info (rw includes md and mc):");
422 tty->print_cr("%s", hdr);
423 tty->print_cr("%s", sep);
424 for (int type = 0; type < int(_number_of_types); type ++) {
425 const char *name = type_name((Type)type);
426 int ro_count = _counts[RO][type];
427 int ro_bytes = _bytes [RO][type];
428 int rw_count = _counts[RW][type];
429 int rw_bytes = _bytes [RW][type];
430 int count = ro_count + rw_count;
431 int bytes = ro_bytes + rw_bytes;
432
433 double ro_perc = 100.0 * double(ro_bytes) / double(ro_all);
434 double rw_perc = 100.0 * double(rw_bytes) / double(rw_all);
435 double perc = 100.0 * double(bytes) / double(ro_all + rw_all);
436
437 tty->print_cr(fmt_stats, name,
438 ro_count, ro_bytes, ro_perc,
439 rw_count, rw_bytes, rw_perc,
440 count, bytes, perc);
441
442 all_ro_count += ro_count;
443 all_ro_bytes += ro_bytes;
444 all_rw_count += rw_count;
445 all_rw_bytes += rw_bytes;
446 }
447
448 int all_count = all_ro_count + all_rw_count;
449 int all_bytes = all_ro_bytes + all_rw_bytes;
450
451 double all_ro_perc = 100.0 * double(all_ro_bytes) / double(ro_all);
452 double all_rw_perc = 100.0 * double(all_rw_bytes) / double(rw_all);
453 double all_perc = 100.0 * double(all_bytes) / double(ro_all + rw_all);
454
455 tty->print_cr("%s", sep);
456 tty->print_cr(fmt_stats, "Total",
457 all_ro_count, all_ro_bytes, all_ro_perc,
458 all_rw_count, all_rw_bytes, all_rw_perc,
459 all_count, all_bytes, all_perc);
460
461 assert(all_ro_bytes == ro_all, "everything should have been counted");
462 assert(all_rw_bytes == rw_all, "everything should have been counted");
463 #undef fmt_stats
464 }
465
466 // Populate the shared space.
467
468 class VM_PopulateDumpSharedSpace: public VM_Operation {
469 private:
470 ClassLoaderData* _loader_data;
471 GrowableArray<Klass*> *_class_promote_order;
472 VirtualSpace _md_vs;
473 VirtualSpace _mc_vs;
474 CompactHashtableWriter* _string_cht;
475 GrowableArray<MemRegion> *_string_regions;
476
477 public:
478 VM_PopulateDumpSharedSpace(ClassLoaderData* loader_data,
479 GrowableArray<Klass*> *class_promote_order) :
480 _loader_data(loader_data) {
481 _class_promote_order = class_promote_order;
482 }
483
484 VMOp_Type type() const { return VMOp_PopulateDumpSharedSpace; }
485 void doit(); // outline because gdb sucks
486
487 private:
488 void handle_misc_data_space_failure(bool success) {
489 if (!success) {
490 report_out_of_shared_space(SharedMiscData);
491 }
492 }
493 }; // class VM_PopulateDumpSharedSpace
494
495 void VM_PopulateDumpSharedSpace::doit() {
496 Thread* THREAD = VMThread::vm_thread();
497 NOT_PRODUCT(SystemDictionary::verify();)
498 // The following guarantee is meant to ensure that no loader constraints
499 // exist yet, since the constraints table is not shared. This becomes
500 // more important now that we don't re-initialize vtables/itables for
501 // shared classes at runtime, where constraints were previously created.
502 guarantee(SystemDictionary::constraints()->number_of_entries() == 0,
503 "loader constraints are not saved");
504 guarantee(SystemDictionary::placeholders()->number_of_entries() == 0,
505 "placeholders are not saved");
506 // Revisit and implement this if we prelink method handle call sites:
507 guarantee(SystemDictionary::invoke_method_table() == NULL ||
508 SystemDictionary::invoke_method_table()->number_of_entries() == 0,
509 "invoke method table is not saved");
510
511 // At this point, many classes have been loaded.
512 // Gather systemDictionary classes in a global array and do everything to
513 // that so we don't have to walk the SystemDictionary again.
514 _global_klass_objects = new GrowableArray<Klass*>(1000);
515 Universe::basic_type_classes_do(collect_classes);
516
517 // Need to call SystemDictionary::classes_do(void f(Klass*, ClassLoaderData*))
518 // as we may have some classes with NULL ClassLoaderData* in the dictionary. Other
519 // variants of SystemDictionary::classes_do will skip those classes.
520 SystemDictionary::classes_do(collect_classes2);
521
522 tty->print_cr("Number of classes %d", _global_klass_objects->length());
523 {
524 int num_type_array = 0, num_obj_array = 0, num_inst = 0;
525 for (int i = 0; i < _global_klass_objects->length(); i++) {
526 Klass* k = _global_klass_objects->at(i);
527 if (k->is_instance_klass()) {
528 num_inst ++;
529 } else if (k->is_objArray_klass()) {
530 num_obj_array ++;
531 } else {
532 assert(k->is_typeArray_klass(), "sanity");
533 num_type_array ++;
534 }
535 }
536 tty->print_cr(" instance classes = %5d", num_inst);
537 tty->print_cr(" obj array classes = %5d", num_obj_array);
538 tty->print_cr(" type array classes = %5d", num_type_array);
539 }
540
541
542 // Ensure the ConstMethods won't be modified at run-time
543 tty->print("Updating ConstMethods ... ");
544 rewrite_nofast_bytecodes_and_calculate_fingerprints();
545 tty->print_cr("done. ");
546
547 // Remove all references outside the metadata
548 tty->print("Removing unshareable information ... ");
549 remove_unshareable_in_classes();
550 tty->print_cr("done. ");
551
552 // Set up the share data and shared code segments.
553 _md_vs = *MetaspaceShared::misc_data_region()->virtual_space();
554 _mc_vs = *MetaspaceShared::misc_code_region()->virtual_space();
555 char* md_low = _md_vs.low();
556 char* md_top = MetaspaceShared::misc_data_region()->alloc_top();
557 char* md_end = _md_vs.high();
558 char* mc_low = _mc_vs.low();
559 char* mc_top = MetaspaceShared::misc_code_region()->alloc_top();
560 char* mc_end = _mc_vs.high();
561
562 // Reserve space for the list of Klass*s whose vtables are used
563 // for patching others as needed.
564
565 void** vtbl_list = (void**)md_top;
566 int vtbl_list_size = MetaspaceShared::vtbl_list_size;
567 Universe::init_self_patching_vtbl_list(vtbl_list, vtbl_list_size);
568
569 md_top += vtbl_list_size * sizeof(void*);
570 void* vtable = md_top;
571
572 // Reserve space for a new dummy vtable for klass objects in the
573 // heap. Generate self-patching vtable entries.
574
575 MetaspaceShared::generate_vtable_methods(vtbl_list, &vtable,
576 &md_top, md_end,
577 &mc_top, mc_end);
578
579 // Reorder the system dictionary. (Moving the symbols affects
580 // how the hash table indices are calculated.)
581 // Not doing this either.
582
583 SystemDictionary::reorder_dictionary();
584
585 NOT_PRODUCT(SystemDictionary::verify();)
586
587 // Copy the symbol table, string table, and the system dictionary to the shared
588 // space in usable form. Copy the hashtable
589 // buckets first [read-write], then copy the linked lists of entries
590 // [read-only].
591
592 NOT_PRODUCT(SymbolTable::verify());
593 handle_misc_data_space_failure(SymbolTable::copy_compact_table(&md_top, md_end));
594
595 size_t ss_bytes = 0;
596 char* ss_low;
597 // The string space has maximum two regions. See FileMapInfo::write_string_regions() for details.
598 _string_regions = new GrowableArray<MemRegion>(2);
599 NOT_PRODUCT(StringTable::verify());
600 handle_misc_data_space_failure(StringTable::copy_compact_table(&md_top, md_end, _string_regions,
601 &ss_bytes));
602 ss_low = _string_regions->is_empty() ? NULL : (char*)_string_regions->first().start();
603
604 SystemDictionary::reverse();
605 SystemDictionary::copy_buckets(&md_top, md_end);
606
607 ClassLoader::verify();
608 ClassLoader::copy_package_info_buckets(&md_top, md_end);
609 ClassLoader::verify();
610
611 SystemDictionary::copy_table(&md_top, md_end);
612 ClassLoader::verify();
613 ClassLoader::copy_package_info_table(&md_top, md_end);
614 ClassLoader::verify();
615
616 // Write the other data to the output array.
617 WriteClosure wc(md_top, md_end);
618 MetaspaceShared::serialize(&wc);
619 md_top = wc.get_top();
620
621 // Print shared spaces all the time
622 // To make fmt_space be a syntactic constant (for format warnings), use #define.
623 #define fmt_space "%s space: " SIZE_FORMAT_W(9) " [ %4.1f%% of total] out of " SIZE_FORMAT_W(9) " bytes [%4.1f%% used] at " INTPTR_FORMAT
624 Metaspace* ro_space = _loader_data->ro_metaspace();
625 Metaspace* rw_space = _loader_data->rw_metaspace();
626
627 // Allocated size of each space (may not be all occupied)
628 const size_t ro_alloced = ro_space->capacity_bytes_slow(Metaspace::NonClassType);
629 const size_t rw_alloced = rw_space->capacity_bytes_slow(Metaspace::NonClassType);
630 const size_t md_alloced = md_end-md_low;
631 const size_t mc_alloced = mc_end-mc_low;
632 const size_t total_alloced = ro_alloced + rw_alloced + md_alloced + mc_alloced
633 + ss_bytes;
634
635 // Occupied size of each space.
636 const size_t ro_bytes = ro_space->used_bytes_slow(Metaspace::NonClassType);
637 const size_t rw_bytes = rw_space->used_bytes_slow(Metaspace::NonClassType);
638 const size_t md_bytes = size_t(md_top - md_low);
639 const size_t mc_bytes = size_t(mc_top - mc_low);
640
641 // Percent of total size
642 const size_t total_bytes = ro_bytes + rw_bytes + md_bytes + mc_bytes + ss_bytes;
643 const double ro_t_perc = ro_bytes / double(total_bytes) * 100.0;
644 const double rw_t_perc = rw_bytes / double(total_bytes) * 100.0;
645 const double md_t_perc = md_bytes / double(total_bytes) * 100.0;
646 const double mc_t_perc = mc_bytes / double(total_bytes) * 100.0;
647 const double ss_t_perc = ss_bytes / double(total_bytes) * 100.0;
648
649 // Percent of fullness of each space
650 const double ro_u_perc = ro_bytes / double(ro_alloced) * 100.0;
651 const double rw_u_perc = rw_bytes / double(rw_alloced) * 100.0;
652 const double md_u_perc = md_bytes / double(md_alloced) * 100.0;
653 const double mc_u_perc = mc_bytes / double(mc_alloced) * 100.0;
654 const double total_u_perc = total_bytes / double(total_alloced) * 100.0;
655
656 tty->print_cr(fmt_space, "ro", ro_bytes, ro_t_perc, ro_alloced, ro_u_perc, p2i(ro_space->bottom()));
657 tty->print_cr(fmt_space, "rw", rw_bytes, rw_t_perc, rw_alloced, rw_u_perc, p2i(rw_space->bottom()));
658 tty->print_cr(fmt_space, "md", md_bytes, md_t_perc, md_alloced, md_u_perc, p2i(md_low));
659 tty->print_cr(fmt_space, "mc", mc_bytes, mc_t_perc, mc_alloced, mc_u_perc, p2i(mc_low));
660 tty->print_cr(fmt_space, "st", ss_bytes, ss_t_perc, ss_bytes, 100.0, p2i(ss_low));
661 tty->print_cr("total : " SIZE_FORMAT_W(9) " [100.0%% of total] out of " SIZE_FORMAT_W(9) " bytes [%4.1f%% used]",
662 total_bytes, total_alloced, total_u_perc);
663
664 // Update the vtable pointers in all of the Klass objects in the
665 // heap. They should point to newly generated vtable.
666 patch_klass_vtables(vtbl_list, vtable);
667
668 // dunno what this is for.
669 char* saved_vtbl = (char*)os::malloc(vtbl_list_size * sizeof(void*), mtClass);
670 memmove(saved_vtbl, vtbl_list, vtbl_list_size * sizeof(void*));
671 memset(vtbl_list, 0, vtbl_list_size * sizeof(void*));
672
673 // Create and write the archive file that maps the shared spaces.
674
675 FileMapInfo* mapinfo = new FileMapInfo();
676 mapinfo->populate_header(MetaspaceShared::max_alignment());
677 mapinfo->set_misc_data_patching_start((char*)vtbl_list);
678
679 for (int pass=1; pass<=2; pass++) {
680 if (pass == 1) {
681 // The first pass doesn't actually write the data to disk. All it
682 // does is to update the fields in the mapinfo->_header.
683 } else {
684 // After the first pass, the contents of mapinfo->_header are finalized,
685 // so we can compute the header's CRC, and write the contents of the header
686 // and the regions into disk.
687 mapinfo->open_for_write();
688 mapinfo->set_header_crc(mapinfo->compute_header_crc());
689 }
690 mapinfo->write_header();
691 mapinfo->write_space(MetaspaceShared::ro, _loader_data->ro_metaspace(), true);
692 mapinfo->write_space(MetaspaceShared::rw, _loader_data->rw_metaspace(), false);
693 mapinfo->write_region(MetaspaceShared::md, _md_vs.low(),
694 pointer_delta(md_top, _md_vs.low(), sizeof(char)),
695 SharedMiscDataSize,
696 false, false);
697 mapinfo->write_region(MetaspaceShared::mc, _mc_vs.low(),
698 pointer_delta(mc_top, _mc_vs.low(), sizeof(char)),
699 SharedMiscCodeSize,
700 true, true);
701 mapinfo->write_string_regions(_string_regions);
702 }
703
704 mapinfo->close();
705
706 memmove(vtbl_list, saved_vtbl, vtbl_list_size * sizeof(void*));
707 os::free(saved_vtbl);
708
709 if (PrintSharedSpaces) {
710 DumpAllocClosure dac;
711 dac.iterate_metaspace(_loader_data->ro_metaspace(), DumpAllocClosure::RO);
712 dac.iterate_metaspace(_loader_data->rw_metaspace(), DumpAllocClosure::RW);
713
714 dac.dump_stats(int(ro_bytes), int(rw_bytes), int(md_bytes), int(mc_bytes));
715 }
716 #undef fmt_space
717 }
718
719
720 void MetaspaceShared::link_one_shared_class(Klass* obj, TRAPS) {
721 Klass* k = obj;
722 if (k->is_instance_klass()) {
723 InstanceKlass* ik = InstanceKlass::cast(k);
724 // Link the class to cause the bytecodes to be rewritten and the
725 // cpcache to be created. Class verification is done according
726 // to -Xverify setting.
727 _link_classes_made_progress |= try_link_class(ik, THREAD);
728 guarantee(!HAS_PENDING_EXCEPTION, "exception in link_class");
729 }
730 }
731
732 void MetaspaceShared::check_one_shared_class(Klass* k) {
733 if (k->is_instance_klass() && InstanceKlass::cast(k)->check_sharing_error_state()) {
734 _check_classes_made_progress = true;
735 }
736 }
737
738 void MetaspaceShared::link_and_cleanup_shared_classes(TRAPS) {
739 // We need to iterate because verification may cause additional classes
740 // to be loaded.
741 do {
742 _link_classes_made_progress = false;
743 SystemDictionary::classes_do(link_one_shared_class, THREAD);
744 guarantee(!HAS_PENDING_EXCEPTION, "exception in link_class");
745 } while (_link_classes_made_progress);
746
747 if (_has_error_classes) {
748 // Mark all classes whose super class or interfaces failed verification.
749 do {
750 // Not completely sure if we need to do this iteratively. Anyway,
751 // we should come here only if there are unverifiable classes, which
752 // shouldn't happen in normal cases. So better safe than sorry.
753 _check_classes_made_progress = false;
754 SystemDictionary::classes_do(check_one_shared_class);
755 } while (_check_classes_made_progress);
756
757 if (IgnoreUnverifiableClassesDuringDump) {
758 // This is useful when running JCK or SQE tests. You should not
759 // enable this when running real apps.
760 SystemDictionary::remove_classes_in_error_state();
761 } else {
762 tty->print_cr("Please remove the unverifiable classes from your class list and try again");
763 exit(1);
764 }
765 }
766 }
767
768 void MetaspaceShared::prepare_for_dumping() {
769 ClassLoader::initialize_shared_path();
770 FileMapInfo::allocate_classpath_entry_table();
771 }
772
773 // Preload classes from a list, populate the shared spaces and dump to a
774 // file.
775 void MetaspaceShared::preload_and_dump(TRAPS) {
776 { TraceStartupTime timer("Dump Shared Spaces");
777 ResourceMark rm;
778 char class_list_path_str[JVM_MAXPATHLEN];
779
780 tty->print_cr("Allocated shared space: " SIZE_FORMAT " bytes at " PTR_FORMAT,
781 MetaspaceShared::shared_rs()->size(),
782 p2i(MetaspaceShared::shared_rs()->base()));
783
784 // Preload classes to be shared.
785 // Should use some os:: method rather than fopen() here. aB.
786 const char* class_list_path;
787 if (SharedClassListFile == NULL) {
788 // Construct the path to the class list (in jre/lib)
789 // Walk up two directories from the location of the VM and
790 // optionally tack on "lib" (depending on platform)
791 os::jvm_path(class_list_path_str, sizeof(class_list_path_str));
792 for (int i = 0; i < 3; i++) {
793 char *end = strrchr(class_list_path_str, *os::file_separator());
794 if (end != NULL) *end = '\0';
795 }
796 int class_list_path_len = (int)strlen(class_list_path_str);
797 if (class_list_path_len >= 3) {
798 if (strcmp(class_list_path_str + class_list_path_len - 3, "lib") != 0) {
799 if (class_list_path_len < JVM_MAXPATHLEN - 4) {
800 jio_snprintf(class_list_path_str + class_list_path_len,
801 sizeof(class_list_path_str) - class_list_path_len,
802 "%slib", os::file_separator());
803 class_list_path_len += 4;
804 }
805 }
806 }
807 if (class_list_path_len < JVM_MAXPATHLEN - 10) {
808 jio_snprintf(class_list_path_str + class_list_path_len,
809 sizeof(class_list_path_str) - class_list_path_len,
810 "%sclasslist", os::file_separator());
811 }
812 class_list_path = class_list_path_str;
813 } else {
814 class_list_path = SharedClassListFile;
815 }
816
817 int class_count = 0;
818 GrowableArray<Klass*>* class_promote_order = new GrowableArray<Klass*>();
819
820 // sun.io.Converters
821 static const char obj_array_sig[] = "[[Ljava/lang/Object;";
822 SymbolTable::new_permanent_symbol(obj_array_sig, THREAD);
823
824 // java.util.HashMap
825 static const char map_entry_array_sig[] = "[Ljava/util/Map$Entry;";
826 SymbolTable::new_permanent_symbol(map_entry_array_sig, THREAD);
827
828 // Need to allocate the op here:
829 // op.misc_data_space_alloc() will be called during preload_and_dump().
830 ClassLoaderData* loader_data = ClassLoaderData::the_null_class_loader_data();
831 VM_PopulateDumpSharedSpace op(loader_data, class_promote_order);
832
833 tty->print_cr("Loading classes to share ...");
834 _has_error_classes = false;
835 class_count += preload_and_dump(class_list_path, class_promote_order,
836 THREAD);
837 if (ExtraSharedClassListFile) {
838 class_count += preload_and_dump(ExtraSharedClassListFile, class_promote_order,
839 THREAD);
840 }
841 tty->print_cr("Loading classes to share: done.");
842
843 if (PrintSharedSpaces) {
844 tty->print_cr("Shared spaces: preloaded %d classes", class_count);
845 }
846
847 // Rewrite and link classes
848 tty->print_cr("Rewriting and linking classes ...");
849
850 // Link any classes which got missed. This would happen if we have loaded classes that
851 // were not explicitly specified in the classlist. E.g., if an interface implemented by class K
852 // fails verification, all other interfaces that were not specified in the classlist but
853 // are implemented by K are not verified.
854 link_and_cleanup_shared_classes(CATCH);
855 tty->print_cr("Rewriting and linking classes: done");
856
857 VMThread::execute(&op);
858 }
859 // Since various initialization steps have been undone by this process,
860 // it is not reasonable to continue running a java process.
861 exit(0);
862 }
863
864
865 int MetaspaceShared::preload_and_dump(const char* class_list_path,
866 GrowableArray<Klass*>* class_promote_order,
867 TRAPS) {
868 ClassListParser parser(class_list_path);
869 int class_count = 0;
870
871 while (parser.parse_one_line()) {
872 Klass* klass = ClassLoaderExt::load_one_class(&parser, THREAD);
873
874 CLEAR_PENDING_EXCEPTION;
875 if (klass != NULL) {
876 if (PrintSharedSpaces && Verbose && WizardMode) {
877 ResourceMark rm;
878 tty->print_cr("Shared spaces preloaded: %s", klass->external_name());
879 }
880
881 InstanceKlass* ik = InstanceKlass::cast(klass);
882
883 // Should be class load order as per -XX:+TraceClassLoadingPreorder
884 class_promote_order->append(ik);
885
886 // Link the class to cause the bytecodes to be rewritten and the
887 // cpcache to be created. The linking is done as soon as classes
888 // are loaded in order that the related data structures (klass and
889 // cpCache) are located together.
890 try_link_class(ik, THREAD);
891 guarantee(!HAS_PENDING_EXCEPTION, "exception in link_class");
892
893 class_count++;
894 }
895 }
896
897 return class_count;
898 }
899
900 // Returns true if the class's status has changed
901 bool MetaspaceShared::try_link_class(InstanceKlass* ik, TRAPS) {
902 assert(DumpSharedSpaces, "should only be called during dumping");
903 if (ik->init_state() < InstanceKlass::linked) {
904 bool saved = BytecodeVerificationLocal;
905 if (!SharedClassUtil::is_shared_boot_class(ik)) {
906 // The verification decision is based on BytecodeVerificationRemote
907 // for non-system classes. Since we are using the NULL classloader
908 // to load non-system classes during dumping, we need to temporarily
909 // change BytecodeVerificationLocal to be the same as
910 // BytecodeVerificationRemote. Note this can cause the parent system
911 // classes also being verified. The extra overhead is acceptable during
912 // dumping.
913 BytecodeVerificationLocal = BytecodeVerificationRemote;
914 }
915 ik->link_class(THREAD);
916 if (HAS_PENDING_EXCEPTION) {
917 ResourceMark rm;
918 tty->print_cr("Preload Warning: Verification failed for %s",
919 ik->external_name());
920 CLEAR_PENDING_EXCEPTION;
921 ik->set_in_error_state();
922 _has_error_classes = true;
923 }
924 BytecodeVerificationLocal = saved;
925 return true;
926 } else {
927 return false;
928 }
929 }
930
931 // Closure for serializing initialization data in from a data area
932 // (ptr_array) read from the shared file.
933
934 class ReadClosure : public SerializeClosure {
935 private:
936 intptr_t** _ptr_array;
937
938 inline intptr_t nextPtr() {
939 return *(*_ptr_array)++;
940 }
941
942 public:
943 ReadClosure(intptr_t** ptr_array) { _ptr_array = ptr_array; }
944
945 void do_ptr(void** p) {
946 assert(*p == NULL, "initializing previous initialized pointer.");
947 intptr_t obj = nextPtr();
948 assert((intptr_t)obj >= 0 || (intptr_t)obj < -100,
949 "hit tag while initializing ptrs.");
950 *p = (void*)obj;
951 }
952
953 void do_tag(int tag) {
954 int old_tag;
955 old_tag = (int)(intptr_t)nextPtr();
956 // do_int(&old_tag);
957 assert(tag == old_tag, "old tag doesn't match");
958 FileMapInfo::assert_mark(tag == old_tag);
959 }
960
961 void do_region(u_char* start, size_t size) {
962 assert((intptr_t)start % sizeof(intptr_t) == 0, "bad alignment");
963 assert(size % sizeof(intptr_t) == 0, "bad size");
964 do_tag((int)size);
965 while (size > 0) {
966 *(intptr_t*)start = nextPtr();
967 start += sizeof(intptr_t);
968 size -= sizeof(intptr_t);
969 }
970 }
971
972 bool reading() const { return true; }
973 };
974
975 // Return true if given address is in the mapped shared space.
976 bool MetaspaceShared::is_in_shared_space(const void* p) {
977 return UseSharedSpaces && FileMapInfo::current_info()->is_in_shared_space(p);
978 }
979
980 bool MetaspaceShared::is_string_region(int idx) {
981 return (idx >= MetaspaceShared::first_string &&
982 idx < MetaspaceShared::first_string + MetaspaceShared::max_strings);
983 }
984
985 void MetaspaceShared::print_shared_spaces() {
986 if (UseSharedSpaces) {
987 FileMapInfo::current_info()->print_shared_spaces();
988 }
989 }
990
991
992 // Map shared spaces at requested addresses and return if succeeded.
993 // Need to keep the bounds of the ro and rw space for the Metaspace::contains
994 // call, or is_in_shared_space.
995 bool MetaspaceShared::map_shared_spaces(FileMapInfo* mapinfo) {
996 size_t image_alignment = mapinfo->alignment();
997
998 #ifndef _WINDOWS
999 // Map in the shared memory and then map the regions on top of it.
1000 // On Windows, don't map the memory here because it will cause the
1001 // mappings of the regions to fail.
1002 ReservedSpace shared_rs = mapinfo->reserve_shared_memory();
1003 if (!shared_rs.is_reserved()) return false;
1004 #endif
1005
1006 assert(!DumpSharedSpaces, "Should not be called with DumpSharedSpaces");
1007
1008 char* _ro_base = NULL;
1009 char* _rw_base = NULL;
1010 char* _md_base = NULL;
1011 char* _mc_base = NULL;
1012
1013 // Map each shared region
1014 if ((_ro_base = mapinfo->map_region(ro)) != NULL &&
1015 mapinfo->verify_region_checksum(ro) &&
1016 (_rw_base = mapinfo->map_region(rw)) != NULL &&
1017 mapinfo->verify_region_checksum(rw) &&
1018 (_md_base = mapinfo->map_region(md)) != NULL &&
1019 mapinfo->verify_region_checksum(md) &&
1020 (_mc_base = mapinfo->map_region(mc)) != NULL &&
1021 mapinfo->verify_region_checksum(mc) &&
1022 (image_alignment == (size_t)max_alignment()) &&
1023 mapinfo->validate_classpath_entry_table()) {
1024 // Success (no need to do anything)
1025 return true;
1026 } else {
1027 // If there was a failure in mapping any of the spaces, unmap the ones
1028 // that succeeded
1029 if (_ro_base != NULL) mapinfo->unmap_region(ro);
1030 if (_rw_base != NULL) mapinfo->unmap_region(rw);
1031 if (_md_base != NULL) mapinfo->unmap_region(md);
1032 if (_mc_base != NULL) mapinfo->unmap_region(mc);
1033 #ifndef _WINDOWS
1034 // Release the entire mapped region
1035 shared_rs.release();
1036 #endif
1037 // If -Xshare:on is specified, print out the error message and exit VM,
1038 // otherwise, set UseSharedSpaces to false and continue.
1039 if (RequireSharedSpaces || PrintSharedArchiveAndExit) {
1040 vm_exit_during_initialization("Unable to use shared archive.", "Failed map_region for using -Xshare:on.");
1041 } else {
1042 FLAG_SET_DEFAULT(UseSharedSpaces, false);
1043 }
1044 return false;
1045 }
1046 }
1047
1048 // Read the miscellaneous data from the shared file, and
1049 // serialize it out to its various destinations.
1050
1051 void MetaspaceShared::initialize_shared_spaces() {
1052 FileMapInfo *mapinfo = FileMapInfo::current_info();
1053 char* buffer = mapinfo->misc_data_patching_start();
1054
1055 // Skip over (reserve space for) a list of addresses of C++ vtables
1056 // for Klass objects. They get filled in later.
1057
1058 void** vtbl_list = (void**)buffer;
1059 buffer += MetaspaceShared::vtbl_list_size * sizeof(void*);
1060 Universe::init_self_patching_vtbl_list(vtbl_list, vtbl_list_size);
1061
1062 // Skip over (reserve space for) dummy C++ vtables Klass objects.
1063 // They are used as is.
1064
1065 intptr_t vtable_size = *(intptr_t*)buffer;
1066 buffer += sizeof(intptr_t);
1067 buffer += vtable_size;
1068
1069 // Create the shared symbol table using the compact table at this spot in the
1070 // misc data space. (Todo: move this to read-only space. Currently
1071 // this is mapped copy-on-write but will never be written into).
1072
1073 buffer = (char*)SymbolTable::init_shared_table(buffer);
1074 SymbolTable::create_table();
1075
1076 // Create the shared string table using the compact table
1077 buffer = (char*)StringTable::init_shared_table(mapinfo, buffer);
1078
1079 // Create the shared dictionary using the bucket array at this spot in
1080 // the misc data space. Since the shared dictionary table is never
1081 // modified, this region (of mapped pages) will be (effectively, if
1082 // not explicitly) read-only.
1083
1084 int sharedDictionaryLen = *(intptr_t*)buffer;
1085 buffer += sizeof(intptr_t);
1086 int number_of_entries = *(intptr_t*)buffer;
1087 buffer += sizeof(intptr_t);
1088 SystemDictionary::set_shared_dictionary((HashtableBucket<mtClass>*)buffer,
1089 sharedDictionaryLen,
1090 number_of_entries);
1091 buffer += sharedDictionaryLen;
1092
1093 // Create the package info table using the bucket array at this spot in
1094 // the misc data space. Since the package info table is never
1095 // modified, this region (of mapped pages) will be (effectively, if
1096 // not explicitly) read-only.
1097
1098 int pkgInfoLen = *(intptr_t*)buffer;
1099 buffer += sizeof(intptr_t);
1100 number_of_entries = *(intptr_t*)buffer;
1101 buffer += sizeof(intptr_t);
1102 ClassLoader::create_package_info_table((HashtableBucket<mtClass>*)buffer, pkgInfoLen,
1103 number_of_entries);
1104 buffer += pkgInfoLen;
1105 ClassLoader::verify();
1106
1107 // The following data in the shared misc data region are the linked
1108 // list elements (HashtableEntry objects) for the shared dictionary
1109 // and package info table.
1110
1111 int len = *(intptr_t*)buffer; // skip over shared dictionary entries
1112 buffer += sizeof(intptr_t);
1113 buffer += len;
1114
1115 len = *(intptr_t*)buffer; // skip over package info table entries
1116 buffer += sizeof(intptr_t);
1117 buffer += len;
1118
1119 len = *(intptr_t*)buffer; // skip over package info table char[] arrays.
1120 buffer += sizeof(intptr_t);
1121 buffer += len;
1122
1123 intptr_t* array = (intptr_t*)buffer;
1124 ReadClosure rc(&array);
1125 serialize(&rc);
1126
1127 // Close the mapinfo file
1128 mapinfo->close();
1129
1130 if (PrintSharedArchiveAndExit) {
1131 if (PrintSharedDictionary) {
1132 tty->print_cr("\nShared classes:\n");
1133 SystemDictionary::print_shared(false);
1134 }
1135 if (_archive_loading_failed) {
1136 tty->print_cr("archive is invalid");
1137 vm_exit(1);
1138 } else {
1139 tty->print_cr("archive is valid");
1140 vm_exit(0);
1141 }
1142 }
1143 }
1144
1145 void MetaspaceShared::fixup_shared_string_regions() {
1146 FileMapInfo *mapinfo = FileMapInfo::current_info();
1147 mapinfo->fixup_string_regions();
1148 }
1149
1150 // JVM/TI RedefineClasses() support:
1151 bool MetaspaceShared::remap_shared_readonly_as_readwrite() {
1152 assert(SafepointSynchronize::is_at_safepoint(), "must be at safepoint");
1153
1154 if (UseSharedSpaces) {
1155 // remap the shared readonly space to shared readwrite, private
1156 FileMapInfo* mapinfo = FileMapInfo::current_info();
1157 if (!mapinfo->remap_shared_readonly_as_readwrite()) {
1158 return false;
1159 }
1160 }
1161 return true;
1162 }
1163
1164 int MetaspaceShared::count_class(const char* classlist_file) {
1165 if (classlist_file == NULL) {
1166 return 0;
1167 }
1168 char class_name[256];
1169 int class_count = 0;
1170 FILE* file = fopen(classlist_file, "r");
1171 if (file != NULL) {
1172 while ((fgets(class_name, sizeof class_name, file)) != NULL) {
1173 if (*class_name == '#') { // comment
1174 continue;
1175 }
1176 class_count++;
1177 }
1178 fclose(file);
1179 } else {
1180 char errmsg[JVM_MAXPATHLEN];
1181 os::lasterror(errmsg, JVM_MAXPATHLEN);
1182 tty->print_cr("Loading classlist failed: %s", errmsg);
1183 exit(1);
1184 }
1185
1186 return class_count;
1187 }
1188
1189 // the sizes are good for typical large applications that have a lot of shared
1190 // classes
1191 void MetaspaceShared::estimate_regions_size() {
1192 int class_count = count_class(SharedClassListFile);
1193 class_count += count_class(ExtraSharedClassListFile);
1194
1195 if (class_count > LargeThresholdClassCount) {
1196 if (class_count < HugeThresholdClassCount) {
1197 SET_ESTIMATED_SIZE(Large, ReadOnly);
1198 SET_ESTIMATED_SIZE(Large, ReadWrite);
1199 SET_ESTIMATED_SIZE(Large, MiscData);
1200 SET_ESTIMATED_SIZE(Large, MiscCode);
1201 } else {
1202 SET_ESTIMATED_SIZE(Huge, ReadOnly);
1203 SET_ESTIMATED_SIZE(Huge, ReadWrite);
1204 SET_ESTIMATED_SIZE(Huge, MiscData);
1205 SET_ESTIMATED_SIZE(Huge, MiscCode);
1206 }
1207 }
1208 }