1 /*
2 * Copyright (c) 1997, 2026, 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 "cds/aotMetaspace.hpp"
26 #include "cds/cdsConfig.hpp"
27 #include "cds/dynamicArchive.hpp"
28 #include "cds/heapShared.inline.hpp"
29 #include "classfile/classLoader.hpp"
30 #include "classfile/classLoaderDataGraph.hpp"
31 #include "classfile/classLoaderDataShared.hpp"
32 #include "classfile/javaClasses.hpp"
33 #include "classfile/stringTable.hpp"
34 #include "classfile/symbolTable.hpp"
35 #include "classfile/systemDictionary.hpp"
36 #include "classfile/vmClasses.hpp"
37 #include "classfile/vmSymbols.hpp"
38 #include "code/codeBehaviours.hpp"
39 #include "code/codeCache.hpp"
40 #include "compiler/oopMap.hpp"
41 #include "gc/shared/collectedHeap.inline.hpp"
42 #include "gc/shared/gcArguments.hpp"
43 #include "gc/shared/gcConfig.hpp"
44 #include "gc/shared/gcLogPrecious.hpp"
45 #include "gc/shared/gcTraceTime.inline.hpp"
46 #include "gc/shared/oopStorageSet.hpp"
47 #include "gc/shared/plab.hpp"
48 #include "gc/shared/stringdedup/stringDedup.hpp"
49 #include "gc/shared/tlab_globals.hpp"
50 #include "logging/log.hpp"
51 #include "logging/logStream.hpp"
52 #include "memory/memoryReserver.hpp"
53 #include "memory/metadataFactory.hpp"
54 #include "memory/metaspaceClosure.hpp"
55 #include "memory/metaspaceCounters.hpp"
56 #include "memory/metaspaceUtils.hpp"
57 #include "memory/oopFactory.hpp"
58 #include "memory/resourceArea.hpp"
59 #include "memory/universe.hpp"
60 #include "oops/compressedOops.hpp"
61 #include "oops/instanceKlass.hpp"
62 #include "oops/instanceMirrorKlass.hpp"
63 #include "oops/jmethodIDTable.hpp"
64 #include "oops/klass.inline.hpp"
65 #include "oops/objArrayOop.inline.hpp"
66 #include "oops/objLayout.hpp"
67 #include "oops/oop.inline.hpp"
68 #include "oops/oopHandle.inline.hpp"
69 #include "oops/refArrayKlass.hpp"
70 #include "oops/typeArrayKlass.hpp"
71 #include "prims/resolvedMethodTable.hpp"
72 #include "runtime/arguments.hpp"
73 #include "runtime/atomicAccess.hpp"
74 #include "runtime/cpuTimeCounters.hpp"
75 #include "runtime/flags/jvmFlagLimit.hpp"
76 #include "runtime/handles.inline.hpp"
77 #include "runtime/init.hpp"
78 #include "runtime/java.hpp"
79 #include "runtime/javaThread.hpp"
80 #include "runtime/jniHandles.hpp"
81 #include "runtime/threads.hpp"
82 #include "runtime/timerTrace.hpp"
83 #include "sanitizers/leak.hpp"
84 #include "services/cpuTimeUsage.hpp"
85 #include "services/memoryService.hpp"
86 #include "utilities/align.hpp"
87 #include "utilities/autoRestore.hpp"
88 #include "utilities/debug.hpp"
89 #include "utilities/formatBuffer.hpp"
90 #include "utilities/globalDefinitions.hpp"
91 #include "utilities/macros.hpp"
92 #include "utilities/ostream.hpp"
93 #include "utilities/preserveException.hpp"
94
95 // A helper class for caching a Method* when the user of the cache
96 // only cares about the latest version of the Method*. This cache safely
97 // interacts with the RedefineClasses API.
98 class LatestMethodCache {
99 // We save the InstanceKlass* and the idnum of Method* in order to get
100 // the current Method*.
101 InstanceKlass* _klass;
102 int _method_idnum;
103
104 public:
105 LatestMethodCache() { _klass = nullptr; _method_idnum = -1; }
106
107 void init(JavaThread* current, InstanceKlass* ik, const char* method,
108 Symbol* signature, bool is_static);
109 Method* get_method();
110 };
111
112 static LatestMethodCache _finalizer_register_cache; // Finalizer.register()
113 static LatestMethodCache _loader_addClass_cache; // ClassLoader.addClass()
114 static LatestMethodCache _throw_illegal_access_error_cache; // Unsafe.throwIllegalAccessError()
115 static LatestMethodCache _throw_no_such_method_error_cache; // Unsafe.throwNoSuchMethodError()
116 static LatestMethodCache _do_stack_walk_cache; // AbstractStackWalker.doStackWalk()
117 static LatestMethodCache _is_substitutable_cache; // ValueObjectMethods.isSubstitutable()
118 static LatestMethodCache _value_object_hash_code_cache; // ValueObjectMethods.valueObjectHashCode()
119
120 // Known objects
121 TypeArrayKlass* Universe::_typeArrayKlasses[T_LONG+1] = { nullptr /*, nullptr...*/ };
122 ObjArrayKlass* Universe::_objectArrayKlass = nullptr;
123 Klass* Universe::_fillerArrayKlass = nullptr;
124 OopHandle Universe::_basic_type_mirrors[T_VOID+1];
125 #if INCLUDE_CDS_JAVA_HEAP
126 int Universe::_archived_basic_type_mirror_indices[T_VOID+1];
127 #endif
128
129 OopHandle Universe::_main_thread_group;
130 OopHandle Universe::_system_thread_group;
131 OopHandle Universe::_the_empty_class_array;
132 OopHandle Universe::_the_null_string;
133 OopHandle Universe::_the_min_jint_string;
134
135 OopHandle Universe::_the_null_sentinel;
136
137 // _out_of_memory_errors is an objArray
138 enum OutOfMemoryInstance { _oom_java_heap,
139 _oom_c_heap,
140 _oom_metaspace,
141 _oom_class_metaspace,
142 _oom_array_size,
143 _oom_gc_overhead_limit,
144 _oom_realloc_objects,
145 _oom_count };
146
147 OopHandle Universe::_out_of_memory_errors;
148 OopHandle Universe:: _class_init_stack_overflow_error;
149 OopHandle Universe::_delayed_stack_overflow_error_message;
150 OopHandle Universe::_preallocated_out_of_memory_error_array;
151 volatile jint Universe::_preallocated_out_of_memory_error_avail_count = 0;
152
153 // Message details for OOME objects, preallocate these objects since they could be
154 // used when throwing OOME, we should try to avoid further allocation in such case
155 OopHandle Universe::_msg_metaspace;
156 OopHandle Universe::_msg_class_metaspace;
157
158 OopHandle Universe::_reference_pending_list;
159
160 Array<Klass*>* Universe::_the_array_interfaces_array = nullptr;
161
162 long Universe::verify_flags = Universe::Verify_All;
163
164 Array<int>* Universe::_the_empty_int_array = nullptr;
165 Array<u2>* Universe::_the_empty_short_array = nullptr;
166 Array<Klass*>* Universe::_the_empty_klass_array = nullptr;
167 Array<InstanceKlass*>* Universe::_the_empty_instance_klass_array = nullptr;
168 Array<Method*>* Universe::_the_empty_method_array = nullptr;
169
170 uintx Universe::_the_array_interfaces_bitmap = 0;
171 uintx Universe::_the_empty_klass_bitmap = 0;
172
173 // These variables are guarded by FullGCALot_lock.
174 DEBUG_ONLY(OopHandle Universe::_fullgc_alot_dummy_array;)
175 DEBUG_ONLY(int Universe::_fullgc_alot_dummy_next = 0;)
176
177 // Heap
178 int Universe::_verify_count = 0;
179
180 // Oop verification (see MacroAssembler::verify_oop)
181 uintptr_t Universe::_verify_oop_mask = 0;
182 uintptr_t Universe::_verify_oop_bits = (uintptr_t) -1;
183
184 int Universe::_base_vtable_size = 0;
185 bool Universe::_bootstrapping = false;
186 bool Universe::_module_initialized = false;
187 bool Universe::_fully_initialized = false;
188
189 OopStorage* Universe::_vm_weak = nullptr;
190 OopStorage* Universe::_vm_global = nullptr;
191
192 CollectedHeap* Universe::_collectedHeap = nullptr;
193
194 // These are the exceptions that are always created and are guatanteed to exist.
195 // If possible, they can be stored as CDS archived objects to speed up AOT code.
196 class BuiltinException {
197 OopHandle _instance;
198 CDS_JAVA_HEAP_ONLY(int _archived_root_index;)
199
200 public:
201 BuiltinException() : _instance() {
202 CDS_JAVA_HEAP_ONLY(_archived_root_index = 0);
203 }
204
205 void init_if_empty(Symbol* symbol, TRAPS) {
206 if (_instance.is_empty()) {
207 Klass* k = SystemDictionary::resolve_or_fail(symbol, true, CHECK);
208 oop obj = InstanceKlass::cast(k)->allocate_instance(CHECK);
209 _instance = OopHandle(Universe::vm_global(), obj);
210 }
211 }
212
213 oop instance() {
214 return _instance.resolve();
215 }
216
217 #if INCLUDE_CDS_JAVA_HEAP
218 void store_in_cds() {
219 _archived_root_index = HeapShared::archive_exception_instance(instance());
220 }
221
222 void load_from_cds() {
223 if (_archived_root_index >= 0) {
224 oop obj = HeapShared::get_root(_archived_root_index);
225 assert(obj != nullptr, "must be");
226 _instance = OopHandle(Universe::vm_global(), obj);
227 }
228 }
229
230 void serialize(SerializeClosure *f) {
231 f->do_int(&_archived_root_index);
232 }
233 #endif
234 };
235
236 static BuiltinException _null_ptr_exception;
237 static BuiltinException _arithmetic_exception;
238 static BuiltinException _internal_error;
239 static BuiltinException _array_index_out_of_bounds_exception;
240 static BuiltinException _array_store_exception;
241 static BuiltinException _class_cast_exception;
242 static BuiltinException _preempted_exception;
243
244 objArrayOop Universe::the_empty_class_array () {
245 return (objArrayOop)_the_empty_class_array.resolve();
246 }
247
248 oop Universe::main_thread_group() { return _main_thread_group.resolve(); }
249 void Universe::set_main_thread_group(oop group) { _main_thread_group = OopHandle(vm_global(), group); }
250
251 oop Universe::system_thread_group() { return _system_thread_group.resolve(); }
252 void Universe::set_system_thread_group(oop group) { _system_thread_group = OopHandle(vm_global(), group); }
253
254 oop Universe::the_null_string() { return _the_null_string.resolve(); }
255 oop Universe::the_min_jint_string() { return _the_min_jint_string.resolve(); }
256
257 oop Universe::null_ptr_exception_instance() { return _null_ptr_exception.instance(); }
258 oop Universe::arithmetic_exception_instance() { return _arithmetic_exception.instance(); }
259 oop Universe::internal_error_instance() { return _internal_error.instance(); }
260 oop Universe::array_index_out_of_bounds_exception_instance() { return _array_index_out_of_bounds_exception.instance(); }
261 oop Universe::array_store_exception_instance() { return _array_store_exception.instance(); }
262 oop Universe::class_cast_exception_instance() { return _class_cast_exception.instance(); }
263 oop Universe::preempted_exception_instance() { return _preempted_exception.instance(); }
264
265 oop Universe::the_null_sentinel() { return _the_null_sentinel.resolve(); }
266
267 oop Universe::int_mirror() { return check_mirror(_basic_type_mirrors[T_INT].resolve()); }
268 oop Universe::float_mirror() { return check_mirror(_basic_type_mirrors[T_FLOAT].resolve()); }
269 oop Universe::double_mirror() { return check_mirror(_basic_type_mirrors[T_DOUBLE].resolve()); }
270 oop Universe::byte_mirror() { return check_mirror(_basic_type_mirrors[T_BYTE].resolve()); }
271 oop Universe::bool_mirror() { return check_mirror(_basic_type_mirrors[T_BOOLEAN].resolve()); }
272 oop Universe::char_mirror() { return check_mirror(_basic_type_mirrors[T_CHAR].resolve()); }
273 oop Universe::long_mirror() { return check_mirror(_basic_type_mirrors[T_LONG].resolve()); }
274 oop Universe::short_mirror() { return check_mirror(_basic_type_mirrors[T_SHORT].resolve()); }
275 oop Universe::void_mirror() { return check_mirror(_basic_type_mirrors[T_VOID].resolve()); }
276
277 oop Universe::java_mirror(BasicType t) {
278 assert((uint)t < T_VOID+1, "range check");
279 assert(!is_reference_type(t), "sanity");
280 return check_mirror(_basic_type_mirrors[t].resolve());
281 }
282
283 void Universe::basic_type_classes_do(KlassClosure *closure) {
284 for (int i = T_BOOLEAN; i < T_LONG+1; i++) {
285 closure->do_klass(_typeArrayKlasses[i]);
286 }
287 // We don't do the following because it will confuse JVMTI.
288 // _fillerArrayKlass is used only by GC, which doesn't need to see
289 // this klass from basic_type_classes_do().
290 //
291 // closure->do_klass(_fillerArrayKlass);
292 }
293
294 void Universe::metaspace_pointers_do(MetaspaceClosure* it) {
295 it->push(&_fillerArrayKlass);
296 for (int i = 0; i < T_LONG+1; i++) {
297 it->push(&_typeArrayKlasses[i]);
298 }
299 it->push(&_objectArrayKlass);
300
301 it->push(&_the_empty_int_array);
302 it->push(&_the_empty_short_array);
303 it->push(&_the_empty_klass_array);
304 it->push(&_the_empty_instance_klass_array);
305 it->push(&_the_empty_method_array);
306 it->push(&_the_array_interfaces_array);
307 }
308
309 #if INCLUDE_CDS_JAVA_HEAP
310 void Universe::set_archived_basic_type_mirror_index(BasicType t, int index) {
311 assert(CDSConfig::is_dumping_heap(), "sanity");
312 assert(!is_reference_type(t), "sanity");
313 _archived_basic_type_mirror_indices[t] = index;
314 }
315
316 void Universe::archive_exception_instances() {
317 _null_ptr_exception.store_in_cds();
318 _arithmetic_exception.store_in_cds();
319 _internal_error.store_in_cds();
320 _array_index_out_of_bounds_exception.store_in_cds();
321 _array_store_exception.store_in_cds();
322 _class_cast_exception.store_in_cds();
323 _preempted_exception.store_in_cds();
324 }
325
326 void Universe::load_archived_object_instances() {
327 if (HeapShared::is_archived_heap_in_use()) {
328 for (int i = T_BOOLEAN; i < T_VOID+1; i++) {
329 int index = _archived_basic_type_mirror_indices[i];
330 if (!is_reference_type((BasicType)i) && index >= 0) {
331 oop mirror_oop = HeapShared::get_root(index);
332 assert(mirror_oop != nullptr, "must be");
333 _basic_type_mirrors[i] = OopHandle(vm_global(), mirror_oop);
334 }
335 }
336
337 _null_ptr_exception.load_from_cds();
338 _arithmetic_exception.load_from_cds();
339 _internal_error.load_from_cds();
340 _array_index_out_of_bounds_exception.load_from_cds();
341 _array_store_exception.load_from_cds();
342 _class_cast_exception.load_from_cds();
343 _preempted_exception.load_from_cds();
344 }
345 }
346 #endif
347
348 void Universe::serialize(SerializeClosure* f) {
349
350 #if INCLUDE_CDS_JAVA_HEAP
351 for (int i = T_BOOLEAN; i < T_VOID+1; i++) {
352 f->do_int(&_archived_basic_type_mirror_indices[i]);
353 // if f->reading(): We can't call HeapShared::get_root() yet, as the heap
354 // contents may need to be relocated. _basic_type_mirrors[i] will be
355 // updated later in Universe::load_archived_object_instances().
356 }
357 _null_ptr_exception.serialize(f);
358 _arithmetic_exception.serialize(f);
359 _internal_error.serialize(f);
360 _array_index_out_of_bounds_exception.serialize(f);
361 _array_store_exception.serialize(f);
362 _class_cast_exception.serialize(f);
363 _preempted_exception.serialize(f);
364 #endif
365
366 f->do_ptr(&_fillerArrayKlass);
367 for (int i = 0; i < T_LONG+1; i++) {
368 f->do_ptr(&_typeArrayKlasses[i]);
369 }
370
371 f->do_ptr(&_objectArrayKlass);
372 f->do_ptr(&_the_array_interfaces_array);
373 f->do_ptr(&_the_empty_int_array);
374 f->do_ptr(&_the_empty_short_array);
375 f->do_ptr(&_the_empty_method_array);
376 f->do_ptr(&_the_empty_klass_array);
377 f->do_ptr(&_the_empty_instance_klass_array);
378 }
379
380
381 void Universe::check_alignment(uintx size, uintx alignment, const char* name) {
382 if (size < alignment || size % alignment != 0) {
383 vm_exit_during_initialization(
384 err_msg("Size of %s (%zu bytes) must be aligned to %zu bytes", name, size, alignment));
385 }
386 }
387
388 static void initialize_basic_type_klass(Klass* k, TRAPS) {
389 Klass* ok = vmClasses::Object_klass();
390 #if INCLUDE_CDS
391 if (CDSConfig::is_using_archive()) {
392 ClassLoaderData* loader_data = ClassLoaderData::the_null_class_loader_data();
393 assert(k->super() == ok, "u3");
394 if (k->is_instance_klass()) {
395 InstanceKlass::cast(k)->restore_unshareable_info(loader_data, Handle(), nullptr, CHECK);
396 } else {
397 ArrayKlass::cast(k)->restore_unshareable_info(loader_data, Handle(), CHECK);
398 }
399 } else
400 #endif
401 {
402 k->initialize_supers(ok, nullptr, CHECK);
403 }
404 k->append_to_sibling_list();
405 }
406
407 void Universe::genesis(TRAPS) {
408 ResourceMark rm(THREAD);
409 HandleMark hm(THREAD);
410
411 // Explicit null checks are needed if these offsets are not smaller than the page size
412 if (UseCompactObjectHeaders) {
413 assert(oopDesc::mark_offset_in_bytes() < static_cast<intptr_t>(os::vm_page_size()),
414 "Mark offset is expected to be less than the page size");
415 } else {
416 assert(oopDesc::klass_offset_in_bytes() < static_cast<intptr_t>(os::vm_page_size()),
417 "Klass offset is expected to be less than the page size");
418 }
419 assert(arrayOopDesc::length_offset_in_bytes() < static_cast<intptr_t>(os::vm_page_size()),
420 "Array length offset is expected to be less than the page size");
421
422 { AutoModifyRestore<bool> temporarily(_bootstrapping, true);
423
424 java_lang_Class::allocate_fixup_lists();
425
426 // determine base vtable size; without that we cannot create the array klasses
427 compute_base_vtable_size();
428
429 if (!CDSConfig::is_using_archive()) {
430 // Initialization of the fillerArrayKlass must come before regular
431 // int-TypeArrayKlass so that the int-Array mirror points to the
432 // int-TypeArrayKlass.
433 _fillerArrayKlass = TypeArrayKlass::create_klass(T_INT, "[Ljdk/internal/vm/FillerElement;", CHECK);
434 for (int i = T_BOOLEAN; i < T_LONG+1; i++) {
435 _typeArrayKlasses[i] = TypeArrayKlass::create_klass((BasicType)i, CHECK);
436 }
437
438 ClassLoaderData* null_cld = ClassLoaderData::the_null_class_loader_data();
439
440 _the_array_interfaces_array = MetadataFactory::new_array<Klass*>(null_cld, 2, nullptr, CHECK);
441 _the_empty_int_array = MetadataFactory::new_array<int>(null_cld, 0, CHECK);
442 _the_empty_short_array = MetadataFactory::new_array<u2>(null_cld, 0, CHECK);
443 _the_empty_method_array = MetadataFactory::new_array<Method*>(null_cld, 0, CHECK);
444 _the_empty_klass_array = MetadataFactory::new_array<Klass*>(null_cld, 0, CHECK);
445 _the_empty_instance_klass_array = MetadataFactory::new_array<InstanceKlass*>(null_cld, 0, CHECK);
446 }
447
448 vmSymbols::initialize();
449
450 // Initialize table for matching jmethodID, before SystemDictionary.
451 JmethodIDTable::initialize();
452
453 SystemDictionary::initialize(CHECK);
454
455 // Create string constants
456 oop s = StringTable::intern("null", CHECK);
457 _the_null_string = OopHandle(vm_global(), s);
458 s = StringTable::intern("-2147483648", CHECK);
459 _the_min_jint_string = OopHandle(vm_global(), s);
460
461 #if INCLUDE_CDS
462 if (CDSConfig::is_using_archive()) {
463 // Verify shared interfaces array.
464 assert(_the_array_interfaces_array->at(0) ==
465 vmClasses::Cloneable_klass(), "u3");
466 assert(_the_array_interfaces_array->at(1) ==
467 vmClasses::Serializable_klass(), "u3");
468 } else
469 #endif
470 {
471 // Set up shared interfaces array. (Do this before supers are set up.)
472 _the_array_interfaces_array->at_put(0, vmClasses::Cloneable_klass());
473 _the_array_interfaces_array->at_put(1, vmClasses::Serializable_klass());
474 }
475
476 _the_array_interfaces_bitmap = Klass::compute_secondary_supers_bitmap(_the_array_interfaces_array);
477 _the_empty_klass_bitmap = Klass::compute_secondary_supers_bitmap(_the_empty_klass_array);
478
479 initialize_basic_type_klass(_fillerArrayKlass, CHECK);
480
481 initialize_basic_type_klass(boolArrayKlass(), CHECK);
482 initialize_basic_type_klass(charArrayKlass(), CHECK);
483 initialize_basic_type_klass(floatArrayKlass(), CHECK);
484 initialize_basic_type_klass(doubleArrayKlass(), CHECK);
485 initialize_basic_type_klass(byteArrayKlass(), CHECK);
486 initialize_basic_type_klass(shortArrayKlass(), CHECK);
487 initialize_basic_type_klass(intArrayKlass(), CHECK);
488 initialize_basic_type_klass(longArrayKlass(), CHECK);
489
490 assert(_fillerArrayKlass != intArrayKlass(),
491 "Internal filler array klass should be different to int array Klass");
492 } // end of core bootstrapping
493
494 {
495 Handle tns = java_lang_String::create_from_str("<null_sentinel>", CHECK);
496 _the_null_sentinel = OopHandle(vm_global(), tns());
497 }
498
499 // Create a handle for reference_pending_list
500 _reference_pending_list = OopHandle(vm_global(), nullptr);
501
502 // Maybe this could be lifted up now that object array can be initialized
503 // during the bootstrapping.
504
505 // OLD
506 // Initialize _objectArrayKlass after core bootstraping to make
507 // sure the super class is set up properly for _objectArrayKlass.
508 // ---
509 // NEW
510 // Since some of the old system object arrays have been converted to
511 // ordinary object arrays, _objectArrayKlass will be loaded when
512 // SystemDictionary::initialize(CHECK); is run. See the extra check
513 // for Object_klass_is_loaded in ObjArrayKlass::allocate_objArray_klass.
514 {
515 ArrayKlass* oak = vmClasses::Object_klass()->array_klass(CHECK);
516 oak->append_to_sibling_list();
517
518 // Create a RefArrayKlass (which is the default) and initialize.
519 ObjArrayKlass* rak = ObjArrayKlass::cast(oak)->klass_with_properties(ArrayKlass::ArrayProperties::DEFAULT, THREAD);
520 _objectArrayKlass = rak;
521 }
522
523 #ifdef ASSERT
524 if (FullGCALot) {
525 // Allocate an array of dummy objects.
526 // We'd like these to be at the bottom of the old generation,
527 // so that when we free one and then collect,
528 // (almost) the whole heap moves
529 // and we find out if we actually update all the oops correctly.
530 // But we can't allocate directly in the old generation,
531 // so we allocate wherever, and hope that the first collection
532 // moves these objects to the bottom of the old generation.
533 int size = FullGCALotDummies * 2;
534
535 objArrayOop naked_array = oopFactory::new_objArray(vmClasses::Object_klass(), size, CHECK);
536 objArrayHandle dummy_array(THREAD, naked_array);
537 int i = 0;
538 while (i < size) {
539 // Allocate dummy in old generation
540 oop dummy = vmClasses::Object_klass()->allocate_instance(CHECK);
541 dummy_array->obj_at_put(i++, dummy);
542 }
543 {
544 // Only modify the global variable inside the mutex.
545 // If we had a race to here, the other dummy_array instances
546 // and their elements just get dropped on the floor, which is fine.
547 MutexLocker ml(THREAD, FullGCALot_lock, Mutex::_no_safepoint_check_flag);
548 if (_fullgc_alot_dummy_array.is_empty()) {
549 _fullgc_alot_dummy_array = OopHandle(vm_global(), dummy_array());
550 }
551 }
552 assert(i == ((objArrayOop)_fullgc_alot_dummy_array.resolve())->length(), "just checking");
553 }
554 #endif
555 }
556
557 void Universe::initialize_basic_type_mirrors(TRAPS) {
558 #if INCLUDE_CDS_JAVA_HEAP
559 if (CDSConfig::is_using_archive() &&
560 HeapShared::is_archived_heap_in_use() &&
561 _basic_type_mirrors[T_INT].resolve() != nullptr) {
562 // check that all basic type mirrors are mapped also
563 for (int i = T_BOOLEAN; i < T_VOID+1; i++) {
564 if (!is_reference_type((BasicType)i)) {
565 oop m = _basic_type_mirrors[i].resolve();
566 assert(m != nullptr, "archived mirrors should not be null");
567 }
568 }
569 } else
570 // _basic_type_mirrors[T_INT], etc, are null if not using an archived heap
571 #endif
572 {
573 for (int i = T_BOOLEAN; i < T_VOID+1; i++) {
574 BasicType bt = (BasicType)i;
575 if (!is_reference_type(bt)) {
576 oop m = java_lang_Class::create_basic_type_mirror(type2name(bt), bt, CHECK);
577 _basic_type_mirrors[i] = OopHandle(vm_global(), m);
578 }
579 CDS_JAVA_HEAP_ONLY(_archived_basic_type_mirror_indices[i] = -1);
580 }
581 }
582 if (CDSConfig::is_dumping_heap()) {
583 HeapShared::init_scratch_objects_for_basic_type_mirrors(CHECK);
584 }
585 }
586
587 void Universe::fixup_mirrors(TRAPS) {
588 if (CDSConfig::is_using_aot_linked_classes()) {
589 // All mirrors of preloaded classes are already restored. No need to fix up.
590 return;
591 }
592
593 // Bootstrap problem: all classes gets a mirror (java.lang.Class instance) assigned eagerly,
594 // but we cannot do that for classes created before java.lang.Class is loaded. Here we simply
595 // walk over permanent objects created so far (mostly classes) and fixup their mirrors. Note
596 // that the number of objects allocated at this point is very small.
597 assert(vmClasses::Class_klass_is_loaded(), "java.lang.Class should be loaded");
598 HandleMark hm(THREAD);
599
600 if (!CDSConfig::is_using_archive()) {
601 // Cache the start of the static fields
602 InstanceMirrorKlass::init_offset_of_static_fields();
603 }
604
605 GrowableArray <Klass*>* list = java_lang_Class::fixup_mirror_list();
606 int list_length = list->length();
607 for (int i = 0; i < list_length; i++) {
608 Klass* k = list->at(i);
609 assert(k->is_klass(), "List should only hold classes");
610 java_lang_Class::fixup_mirror(k, CATCH);
611 }
612 delete java_lang_Class::fixup_mirror_list();
613 java_lang_Class::set_fixup_mirror_list(nullptr);
614 }
615
616 #define assert_pll_locked(test) \
617 assert(Heap_lock->test(), "Reference pending list access requires lock")
618
619 #define assert_pll_ownership() assert_pll_locked(owned_by_self)
620
621 oop Universe::reference_pending_list() {
622 if (Thread::current()->is_VM_thread()) {
623 assert_pll_locked(is_locked);
624 } else {
625 assert_pll_ownership();
626 }
627 return _reference_pending_list.resolve();
628 }
629
630 void Universe::clear_reference_pending_list() {
631 assert_pll_ownership();
632 _reference_pending_list.replace(nullptr);
633 }
634
635 bool Universe::has_reference_pending_list() {
636 assert_pll_ownership();
637 return _reference_pending_list.peek() != nullptr;
638 }
639
640 oop Universe::swap_reference_pending_list(oop list) {
641 assert_pll_locked(is_locked);
642 return _reference_pending_list.xchg(list);
643 }
644
645 #undef assert_pll_locked
646 #undef assert_pll_ownership
647
648 static void reinitialize_vtables() {
649 // The vtables are initialized by starting at java.lang.Object and
650 // initializing through the subclass links, so that the super
651 // classes are always initialized first.
652 for (ClassHierarchyIterator iter(vmClasses::Object_klass()); !iter.done(); iter.next()) {
653 Klass* sub = iter.klass();
654 sub->vtable().initialize_vtable();
655 }
656
657 // This isn't added to the subclass list, so need to reinitialize vtables directly.
658 Universe::objectArrayKlass()->vtable().initialize_vtable();
659 }
660
661 static void reinitialize_itables() {
662
663 class ReinitTableClosure : public KlassClosure {
664 public:
665 void do_klass(Klass* k) {
666 if (k->is_instance_klass()) {
667 InstanceKlass::cast(k)->itable().initialize_itable();
668 }
669 }
670 };
671
672 MutexLocker mcld(ClassLoaderDataGraph_lock);
673 ReinitTableClosure cl;
674 ClassLoaderDataGraph::classes_do(&cl);
675 }
676
677 bool Universe::on_page_boundary(void* addr) {
678 return is_aligned(addr, os::vm_page_size());
679 }
680
681 // the array of preallocated errors with backtraces
682 objArrayOop Universe::preallocated_out_of_memory_errors() {
683 return (objArrayOop)_preallocated_out_of_memory_error_array.resolve();
684 }
685
686 objArrayOop Universe::out_of_memory_errors() { return (objArrayOop)_out_of_memory_errors.resolve(); }
687
688 oop Universe::out_of_memory_error_java_heap() {
689 return gen_out_of_memory_error(out_of_memory_errors()->obj_at(_oom_java_heap));
690 }
691
692 oop Universe::out_of_memory_error_java_heap_without_backtrace() {
693 return out_of_memory_errors()->obj_at(_oom_java_heap);
694 }
695
696 oop Universe::out_of_memory_error_c_heap() {
697 return gen_out_of_memory_error(out_of_memory_errors()->obj_at(_oom_c_heap));
698 }
699
700 oop Universe::out_of_memory_error_metaspace() {
701 return gen_out_of_memory_error(out_of_memory_errors()->obj_at(_oom_metaspace));
702 }
703
704 oop Universe::out_of_memory_error_class_metaspace() {
705 return gen_out_of_memory_error(out_of_memory_errors()->obj_at(_oom_class_metaspace));
706 }
707
708 oop Universe::out_of_memory_error_array_size() {
709 return gen_out_of_memory_error(out_of_memory_errors()->obj_at(_oom_array_size));
710 }
711
712 oop Universe::out_of_memory_error_gc_overhead_limit() {
713 return gen_out_of_memory_error(out_of_memory_errors()->obj_at(_oom_gc_overhead_limit));
714 }
715
716 oop Universe::out_of_memory_error_realloc_objects() {
717 return gen_out_of_memory_error(out_of_memory_errors()->obj_at(_oom_realloc_objects));
718 }
719
720 oop Universe::class_init_out_of_memory_error() { return out_of_memory_errors()->obj_at(_oom_java_heap); }
721 oop Universe::class_init_stack_overflow_error() { return _class_init_stack_overflow_error.resolve(); }
722 oop Universe::delayed_stack_overflow_error_message() { return _delayed_stack_overflow_error_message.resolve(); }
723
724
725 bool Universe::should_fill_in_stack_trace(Handle throwable) {
726 // never attempt to fill in the stack trace of preallocated errors that do not have
727 // backtrace. These errors are kept alive forever and may be "re-used" when all
728 // preallocated errors with backtrace have been consumed. Also need to avoid
729 // a potential loop which could happen if an out of memory occurs when attempting
730 // to allocate the backtrace.
731 objArrayOop preallocated_oom = out_of_memory_errors();
732 for (int i = 0; i < _oom_count; i++) {
733 if (throwable() == preallocated_oom->obj_at(i)) {
734 return false;
735 }
736 }
737 return true;
738 }
739
740
741 oop Universe::gen_out_of_memory_error(oop default_err) {
742 // generate an out of memory error:
743 // - if there is a preallocated error and stack traces are available
744 // (j.l.Throwable is initialized), then return the preallocated
745 // error with a filled in stack trace, and with the message
746 // provided by the default error.
747 // - otherwise, return the default error, without a stack trace.
748 int next;
749 if ((_preallocated_out_of_memory_error_avail_count > 0) &&
750 vmClasses::Throwable_klass()->is_initialized()) {
751 next = (int)AtomicAccess::add(&_preallocated_out_of_memory_error_avail_count, -1);
752 assert(next < (int)PreallocatedOutOfMemoryErrorCount, "avail count is corrupt");
753 } else {
754 next = -1;
755 }
756 if (next < 0) {
757 // all preallocated errors have been used.
758 // return default
759 return default_err;
760 } else {
761 JavaThread* current = JavaThread::current();
762 Handle default_err_h(current, default_err);
763 // get the error object at the slot and set set it to null so that the
764 // array isn't keeping it alive anymore.
765 Handle exc(current, preallocated_out_of_memory_errors()->obj_at(next));
766 assert(exc() != nullptr, "slot has been used already");
767 preallocated_out_of_memory_errors()->obj_at_put(next, nullptr);
768
769 // use the message from the default error
770 oop msg = java_lang_Throwable::message(default_err_h());
771 assert(msg != nullptr, "no message");
772 java_lang_Throwable::set_message(exc(), msg);
773
774 // populate the stack trace and return it.
775 java_lang_Throwable::fill_in_stack_trace_of_preallocated_backtrace(exc);
776 return exc();
777 }
778 }
779
780 bool Universe::is_out_of_memory_error_metaspace(oop ex_obj) {
781 return java_lang_Throwable::message(ex_obj) == _msg_metaspace.resolve();
782 }
783
784 bool Universe::is_out_of_memory_error_class_metaspace(oop ex_obj) {
785 return java_lang_Throwable::message(ex_obj) == _msg_class_metaspace.resolve();
786 }
787
788 // Setup preallocated OutOfMemoryError errors
789 void Universe::create_preallocated_out_of_memory_errors(TRAPS) {
790 InstanceKlass* ik = vmClasses::OutOfMemoryError_klass();
791 objArrayOop oa = oopFactory::new_objArray(ik, _oom_count, CHECK);
792 objArrayHandle oom_array(THREAD, oa);
793
794 for (int i = 0; i < _oom_count; i++) {
795 oop oom_obj = ik->allocate_instance(CHECK);
796 oom_array->obj_at_put(i, oom_obj);
797 }
798 _out_of_memory_errors = OopHandle(vm_global(), oom_array());
799
800 Handle msg = java_lang_String::create_from_str("Java heap space", CHECK);
801 java_lang_Throwable::set_message(oom_array->obj_at(_oom_java_heap), msg());
802
803 msg = java_lang_String::create_from_str("C heap space", CHECK);
804 java_lang_Throwable::set_message(oom_array->obj_at(_oom_c_heap), msg());
805
806 msg = java_lang_String::create_from_str("Metaspace", CHECK);
807 _msg_metaspace = OopHandle(vm_global(), msg());
808 java_lang_Throwable::set_message(oom_array->obj_at(_oom_metaspace), msg());
809
810 msg = java_lang_String::create_from_str("Compressed class space", CHECK);
811 _msg_class_metaspace = OopHandle(vm_global(), msg());
812 java_lang_Throwable::set_message(oom_array->obj_at(_oom_class_metaspace), msg());
813
814 msg = java_lang_String::create_from_str("Requested array size exceeds VM limit", CHECK);
815 java_lang_Throwable::set_message(oom_array->obj_at(_oom_array_size), msg());
816
817 msg = java_lang_String::create_from_str("GC overhead limit exceeded", CHECK);
818 java_lang_Throwable::set_message(oom_array->obj_at(_oom_gc_overhead_limit), msg());
819
820 msg = java_lang_String::create_from_str("Java heap space: failed reallocation of scalar replaced objects", CHECK);
821 java_lang_Throwable::set_message(oom_array->obj_at(_oom_realloc_objects), msg());
822
823 // Setup the array of errors that have preallocated backtrace
824 int len = (StackTraceInThrowable) ? (int)PreallocatedOutOfMemoryErrorCount : 0;
825 objArrayOop instance = oopFactory::new_objArray(ik, len, CHECK);
826 _preallocated_out_of_memory_error_array = OopHandle(vm_global(), instance);
827 objArrayHandle preallocated_oom_array(THREAD, instance);
828
829 for (int i=0; i<len; i++) {
830 oop err = ik->allocate_instance(CHECK);
831 Handle err_h(THREAD, err);
832 java_lang_Throwable::allocate_backtrace(err_h, CHECK);
833 preallocated_oom_array->obj_at_put(i, err_h());
834 }
835 _preallocated_out_of_memory_error_avail_count = (jint)len;
836 }
837
838 intptr_t Universe::_non_oop_bits = 0;
839
840 void* Universe::non_oop_word() {
841 // Neither the high bits nor the low bits of this value is allowed
842 // to look like (respectively) the high or low bits of a real oop.
843 //
844 // High and low are CPU-specific notions, but low always includes
845 // the low-order bit. Since oops are always aligned at least mod 4,
846 // setting the low-order bit will ensure that the low half of the
847 // word will never look like that of a real oop.
848 //
849 // Using the OS-supplied non-memory-address word (usually 0 or -1)
850 // will take care of the high bits, however many there are.
851
852 if (_non_oop_bits == 0) {
853 _non_oop_bits = (intptr_t)os::non_memory_address_word() | 1;
854 }
855
856 return (void*)_non_oop_bits;
857 }
858
859 bool Universe::contains_non_oop_word(void* p) {
860 return *(void**)p == non_oop_word();
861 }
862
863 static void initialize_global_behaviours() {
864 DefaultICProtectionBehaviour* protection_behavior = new DefaultICProtectionBehaviour();
865 // Ignore leak of DefaultICProtectionBehaviour. It is overriden by some GC implementations and the
866 // pointer is leaked once.
867 LSAN_IGNORE_OBJECT(protection_behavior);
868 CompiledICProtectionBehaviour::set_current(protection_behavior);
869 }
870
871 jint universe_init() {
872 assert(!Universe::_fully_initialized, "called after initialize_vtables");
873 guarantee(1 << LogHeapWordSize == sizeof(HeapWord),
874 "LogHeapWordSize is incorrect.");
875 guarantee(sizeof(oop) >= sizeof(HeapWord), "HeapWord larger than oop?");
876 guarantee(sizeof(oop) % sizeof(HeapWord) == 0,
877 "oop size is not not a multiple of HeapWord size");
878
879 TraceTime timer("Genesis", TRACETIME_LOG(Info, startuptime));
880
881 initialize_global_behaviours();
882
883 GCLogPrecious::initialize();
884
885 // Initialize CPUTimeCounters object, which must be done before creation of the heap.
886 CPUTimeCounters::initialize();
887
888 ObjLayout::initialize();
889
890 #ifdef _LP64
891 AOTMetaspace::adjust_heap_sizes_for_dumping();
892 #endif // _LP64
893
894 GCConfig::arguments()->initialize_heap_sizes();
895
896 jint status = Universe::initialize_heap();
897 if (status != JNI_OK) {
898 return status;
899 }
900
901 Universe::initialize_tlab();
902
903 Metaspace::global_initialize();
904
905 // Initialize performance counters for metaspaces
906 MetaspaceCounters::initialize_performance_counters();
907
908 // Checks 'AfterMemoryInit' constraints.
909 if (!JVMFlagLimit::check_all_constraints(JVMFlagConstraintPhase::AfterMemoryInit)) {
910 return JNI_EINVAL;
911 }
912
913 // Add main_thread to threads list to finish barrier setup with
914 // on_thread_attach. Should be before starting to build Java objects in
915 // the AOT heap loader, which invokes barriers.
916 {
917 JavaThread* main_thread = JavaThread::current();
918 MutexLocker mu(Threads_lock);
919 Threads::add(main_thread);
920 }
921
922 HeapShared::initialize_writing_mode();
923
924 // Create the string table before the AOT object archive is loaded,
925 // as it might need to access the string table.
926 StringTable::create_table();
927
928 #if INCLUDE_CDS
929 if (CDSConfig::is_using_archive()) {
930 // Read the data structures supporting the shared spaces (shared
931 // system dictionary, symbol table, etc.)
932 AOTMetaspace::initialize_shared_spaces();
933 }
934 #endif
935
936 ClassLoaderData::init_null_class_loader_data();
937
938 #if INCLUDE_CDS
939 #if INCLUDE_CDS_JAVA_HEAP
940 if (CDSConfig::is_using_full_module_graph()) {
941 ClassLoaderDataShared::restore_archived_entries_for_null_class_loader_data();
942 }
943 #endif // INCLUDE_CDS_JAVA_HEAP
944 if (CDSConfig::is_dumping_archive()) {
945 CDSConfig::prepare_for_dumping();
946 }
947 #endif
948
949 SymbolTable::create_table();
950
951 if (strlen(VerifySubSet) > 0) {
952 Universe::initialize_verify_flags();
953 }
954
955 ResolvedMethodTable::create_table();
956
957 return JNI_OK;
958 }
959
960 jint Universe::initialize_heap() {
961 assert(_collectedHeap == nullptr, "Heap already created");
962 _collectedHeap = GCConfig::arguments()->create_heap();
963
964 log_info(gc)("Using %s", _collectedHeap->name());
965 return _collectedHeap->initialize();
966 }
967
968 void Universe::initialize_tlab() {
969 ThreadLocalAllocBuffer::set_max_size(Universe::heap()->max_tlab_size());
970 PLAB::startup_initialization();
971 if (UseTLAB) {
972 ThreadLocalAllocBuffer::startup_initialization();
973 }
974 }
975
976 ReservedHeapSpace Universe::reserve_heap(size_t heap_size, size_t alignment, size_t desired_page_size) {
977
978 assert(alignment <= Arguments::conservative_max_heap_alignment(),
979 "actual alignment %zu must be within maximum heap alignment %zu",
980 alignment, Arguments::conservative_max_heap_alignment());
981 assert(is_aligned(heap_size, alignment), "precondition");
982
983 size_t total_reserved = heap_size;
984 assert(!UseCompressedOops || (total_reserved <= (OopEncodingHeapMax - os::vm_page_size())),
985 "heap size is too big for compressed oops");
986
987 size_t page_size;
988 if (desired_page_size == 0) {
989 if (UseLargePages) {
990 page_size = os::large_page_size();
991 } else {
992 page_size = os::vm_page_size();
993 }
994 } else {
995 // Parallel is the only collector that might opt out of using large pages
996 // for the heap.
997 assert(UseParallelGC , "only Parallel");
998 // Use caller provided value.
999 page_size = desired_page_size;
1000 }
1001 assert(is_aligned(heap_size, page_size), "inv");
1002 // Now create the space.
1003 ReservedHeapSpace rhs = HeapReserver::reserve(total_reserved, alignment, page_size, AllocateHeapAt);
1004
1005 if (!rhs.is_reserved()) {
1006 vm_exit_during_initialization(
1007 err_msg("Could not reserve enough space for %zu KB object heap",
1008 total_reserved/K));
1009 }
1010
1011 assert(total_reserved == rhs.size(), "must be exactly of required size");
1012 assert(is_aligned(rhs.base(),alignment),"must be exactly of required alignment");
1013
1014 assert(markWord::encode_pointer_as_mark(rhs.base()).decode_pointer() == rhs.base(),
1015 "area must be distinguishable from marks for mark-sweep");
1016 assert(markWord::encode_pointer_as_mark(&rhs.base()[rhs.size()]).decode_pointer() ==
1017 &rhs.base()[rhs.size()],
1018 "area must be distinguishable from marks for mark-sweep");
1019
1020 // We are good.
1021
1022 if (AllocateHeapAt != nullptr) {
1023 log_info(gc,heap)("Successfully allocated Java heap at location %s", AllocateHeapAt);
1024 }
1025
1026 if (UseCompressedOops) {
1027 CompressedOops::initialize(rhs);
1028 }
1029
1030 Universe::calculate_verify_data((HeapWord*)rhs.base(), (HeapWord*)rhs.end());
1031
1032 return rhs;
1033 }
1034
1035 OopStorage* Universe::vm_weak() {
1036 return Universe::_vm_weak;
1037 }
1038
1039 OopStorage* Universe::vm_global() {
1040 return Universe::_vm_global;
1041 }
1042
1043 void Universe::oopstorage_init() {
1044 Universe::_vm_global = OopStorageSet::create_strong("VM Global", mtInternal);
1045 Universe::_vm_weak = OopStorageSet::create_weak("VM Weak", mtInternal);
1046 }
1047
1048 void universe_oopstorage_init() {
1049 Universe::oopstorage_init();
1050 }
1051
1052 void LatestMethodCache::init(JavaThread* current, InstanceKlass* ik,
1053 const char* method, Symbol* signature, bool is_static)
1054 {
1055 TempNewSymbol name = SymbolTable::new_symbol(method);
1056 Method* m = nullptr;
1057 // The klass must be linked before looking up the method.
1058 if (!ik->link_class_or_fail(current) ||
1059 ((m = ik->find_method(name, signature)) == nullptr) ||
1060 is_static != m->is_static()) {
1061 ResourceMark rm(current);
1062 // NoSuchMethodException doesn't actually work because it tries to run the
1063 // <init> function before java_lang_Class is linked. Print error and exit.
1064 vm_exit_during_initialization(err_msg("Unable to link/verify %s.%s method",
1065 ik->name()->as_C_string(), method));
1066 }
1067
1068 _klass = ik;
1069 _method_idnum = m->method_idnum();
1070 assert(_method_idnum >= 0, "sanity check");
1071 }
1072
1073 Method* LatestMethodCache::get_method() {
1074 if (_klass == nullptr) {
1075 return nullptr;
1076 } else {
1077 Method* m = _klass->method_with_idnum(_method_idnum);
1078 assert(m != nullptr, "sanity check");
1079 return m;
1080 }
1081 }
1082
1083 Method* Universe::finalizer_register_method() { return _finalizer_register_cache.get_method(); }
1084 Method* Universe::loader_addClass_method() { return _loader_addClass_cache.get_method(); }
1085 Method* Universe::throw_illegal_access_error() { return _throw_illegal_access_error_cache.get_method(); }
1086 Method* Universe::throw_no_such_method_error() { return _throw_no_such_method_error_cache.get_method(); }
1087 Method* Universe::do_stack_walk_method() { return _do_stack_walk_cache.get_method(); }
1088 Method* Universe::is_substitutable_method() { return _is_substitutable_cache.get_method(); }
1089 Method* Universe::value_object_hash_code_method() { return _value_object_hash_code_cache.get_method(); }
1090
1091 void Universe::initialize_known_methods(JavaThread* current) {
1092 // Set up static method for registering finalizers
1093 _finalizer_register_cache.init(current,
1094 vmClasses::Finalizer_klass(),
1095 "register",
1096 vmSymbols::object_void_signature(), true);
1097
1098 _throw_illegal_access_error_cache.init(current,
1099 vmClasses::internal_Unsafe_klass(),
1100 "throwIllegalAccessError",
1101 vmSymbols::void_method_signature(), true);
1102
1103 _throw_no_such_method_error_cache.init(current,
1104 vmClasses::internal_Unsafe_klass(),
1105 "throwNoSuchMethodError",
1106 vmSymbols::void_method_signature(), true);
1107
1108 // Set up method for registering loaded classes in class loader vector
1109 _loader_addClass_cache.init(current,
1110 vmClasses::ClassLoader_klass(),
1111 "addClass",
1112 vmSymbols::class_void_signature(), false);
1113
1114 // Set up method for stack walking
1115 _do_stack_walk_cache.init(current,
1116 vmClasses::AbstractStackWalker_klass(),
1117 "doStackWalk",
1118 vmSymbols::doStackWalk_signature(), false);
1119
1120 // Set up substitutability testing
1121 ResourceMark rm(current);
1122 _is_substitutable_cache.init(current,
1123 vmClasses::ValueObjectMethods_klass(),
1124 vmSymbols::isSubstitutable_name()->as_C_string(),
1125 vmSymbols::object_object_boolean_signature(), true);
1126 _value_object_hash_code_cache.init(current,
1127 vmClasses::ValueObjectMethods_klass(),
1128 vmSymbols::valueObjectHashCode_name()->as_C_string(),
1129 vmSymbols::object_int_signature(), true);
1130 }
1131
1132 void universe2_init() {
1133 EXCEPTION_MARK;
1134 Universe::genesis(CATCH);
1135 }
1136
1137 // Set after initialization of the module runtime, call_initModuleRuntime
1138 void universe_post_module_init() {
1139 Universe::_module_initialized = true;
1140 }
1141
1142 bool universe_post_init() {
1143 assert(!is_init_completed(), "Error: initialization not yet completed!");
1144 Universe::_fully_initialized = true;
1145 EXCEPTION_MARK;
1146 if (!CDSConfig::is_using_archive()) {
1147 reinitialize_vtables();
1148 reinitialize_itables();
1149 }
1150
1151 HandleMark hm(THREAD);
1152 // Setup preallocated empty java.lang.Class array for Method reflection.
1153
1154 objArrayOop the_empty_class_array = oopFactory::new_objArray(vmClasses::Class_klass(), 0, CHECK_false);
1155 Universe::_the_empty_class_array = OopHandle(Universe::vm_global(), the_empty_class_array);
1156
1157 // Setup preallocated OutOfMemoryError errors
1158 Universe::create_preallocated_out_of_memory_errors(CHECK_false);
1159
1160 oop instance;
1161 // Setup preallocated cause message for delayed StackOverflowError
1162 if (StackReservedPages > 0) {
1163 instance = java_lang_String::create_oop_from_str("Delayed StackOverflowError due to ReservedStackAccess annotated method", CHECK_false);
1164 Universe::_delayed_stack_overflow_error_message = OopHandle(Universe::vm_global(), instance);
1165 }
1166
1167 // Setup preallocated exceptions used for a cheap & dirty solution in compiler exception handling
1168 _null_ptr_exception.init_if_empty(vmSymbols::java_lang_NullPointerException(), CHECK_false);
1169 _arithmetic_exception.init_if_empty(vmSymbols::java_lang_ArithmeticException(), CHECK_false);
1170 _array_index_out_of_bounds_exception.init_if_empty(vmSymbols::java_lang_ArrayIndexOutOfBoundsException(), CHECK_false);
1171 _array_store_exception.init_if_empty(vmSymbols::java_lang_ArrayStoreException(), CHECK_false);
1172 _class_cast_exception.init_if_empty(vmSymbols::java_lang_ClassCastException(), CHECK_false);
1173 _preempted_exception.init_if_empty(vmSymbols::jdk_internal_vm_PreemptedException(), CHECK_false);
1174
1175 // Virtual Machine Error for when we get into a situation we can't resolve
1176 Klass* k = vmClasses::InternalError_klass();
1177 bool linked = InstanceKlass::cast(k)->link_class_or_fail(CHECK_false);
1178 if (!linked) {
1179 tty->print_cr("Unable to link/verify InternalError class");
1180 return false; // initialization failed
1181 }
1182 _internal_error.init_if_empty(vmSymbols::java_lang_InternalError(), CHECK_false);
1183
1184 Handle msg = java_lang_String::create_from_str("/ by zero", CHECK_false);
1185 java_lang_Throwable::set_message(Universe::arithmetic_exception_instance(), msg());
1186
1187 // Setup preallocated StackOverflowError for use with class initialization failure
1188 k = SystemDictionary::resolve_or_fail(vmSymbols::java_lang_StackOverflowError(), true, CHECK_false);
1189 instance = InstanceKlass::cast(k)->allocate_instance(CHECK_false);
1190 Universe::_class_init_stack_overflow_error = OopHandle(Universe::vm_global(), instance);
1191
1192 Universe::initialize_known_methods(THREAD);
1193
1194 // This needs to be done before the first scavenge/gc, since
1195 // it's an input to soft ref clearing policy.
1196 {
1197 MutexLocker x(THREAD, Heap_lock);
1198 Universe::heap()->update_capacity_and_used_at_gc();
1199 }
1200
1201 // ("weak") refs processing infrastructure initialization
1202 Universe::heap()->post_initialize();
1203
1204 MemoryService::add_metaspace_memory_pools();
1205
1206 MemoryService::set_universe_heap(Universe::heap());
1207
1208 #if INCLUDE_CDS
1209 AOTMetaspace::post_initialize(CHECK_false);
1210 #endif
1211 return true;
1212 }
1213
1214
1215 void Universe::compute_base_vtable_size() {
1216 _base_vtable_size = ClassLoader::compute_Object_vtable();
1217 }
1218
1219 void Universe::print_on(outputStream* st) {
1220 GCMutexLocker hl(Heap_lock); // Heap_lock might be locked by caller thread.
1221 st->print_cr("Heap");
1222
1223 StreamIndentor si(st, 1);
1224 heap()->print_heap_on(st);
1225 MetaspaceUtils::print_on(st);
1226 }
1227
1228 void Universe::print_heap_at_SIGBREAK() {
1229 if (PrintHeapAtSIGBREAK) {
1230 print_on(tty);
1231 tty->cr();
1232 tty->flush();
1233 }
1234 }
1235
1236 void Universe::initialize_verify_flags() {
1237 verify_flags = 0;
1238 const char delimiter[] = " ,";
1239
1240 size_t length = strlen(VerifySubSet);
1241 char* subset_list = NEW_C_HEAP_ARRAY(char, length + 1, mtInternal);
1242 strncpy(subset_list, VerifySubSet, length + 1);
1243 char* save_ptr;
1244
1245 char* token = strtok_r(subset_list, delimiter, &save_ptr);
1246 while (token != nullptr) {
1247 if (strcmp(token, "threads") == 0) {
1248 verify_flags |= Verify_Threads;
1249 } else if (strcmp(token, "heap") == 0) {
1250 verify_flags |= Verify_Heap;
1251 } else if (strcmp(token, "symbol_table") == 0) {
1252 verify_flags |= Verify_SymbolTable;
1253 } else if (strcmp(token, "string_table") == 0) {
1254 verify_flags |= Verify_StringTable;
1255 } else if (strcmp(token, "codecache") == 0) {
1256 verify_flags |= Verify_CodeCache;
1257 } else if (strcmp(token, "dictionary") == 0) {
1258 verify_flags |= Verify_SystemDictionary;
1259 } else if (strcmp(token, "classloader_data_graph") == 0) {
1260 verify_flags |= Verify_ClassLoaderDataGraph;
1261 } else if (strcmp(token, "metaspace") == 0) {
1262 verify_flags |= Verify_MetaspaceUtils;
1263 } else if (strcmp(token, "jni_handles") == 0) {
1264 verify_flags |= Verify_JNIHandles;
1265 } else if (strcmp(token, "codecache_oops") == 0) {
1266 verify_flags |= Verify_CodeCacheOops;
1267 } else if (strcmp(token, "resolved_method_table") == 0) {
1268 verify_flags |= Verify_ResolvedMethodTable;
1269 } else if (strcmp(token, "stringdedup") == 0) {
1270 verify_flags |= Verify_StringDedup;
1271 } else {
1272 vm_exit_during_initialization(err_msg("VerifySubSet: \'%s\' memory sub-system is unknown, please correct it", token));
1273 }
1274 token = strtok_r(nullptr, delimiter, &save_ptr);
1275 }
1276 FREE_C_HEAP_ARRAY(char, subset_list);
1277 }
1278
1279 bool Universe::should_verify_subset(uint subset) {
1280 if (verify_flags & subset) {
1281 return true;
1282 }
1283 return false;
1284 }
1285
1286 void Universe::verify(VerifyOption option, const char* prefix) {
1287 COMPILER2_PRESENT(
1288 assert(!DerivedPointerTable::is_active(),
1289 "DPT should not be active during verification "
1290 "(of thread stacks below)");
1291 )
1292
1293 Thread* thread = Thread::current();
1294 ResourceMark rm(thread);
1295 HandleMark hm(thread); // Handles created during verification can be zapped
1296 _verify_count++;
1297
1298 FormatBuffer<> title("Verifying %s", prefix);
1299 GCTraceTime(Info, gc, verify) tm(title.buffer());
1300 if (should_verify_subset(Verify_Threads)) {
1301 log_debug(gc, verify)("Threads");
1302 Threads::verify();
1303 }
1304 if (should_verify_subset(Verify_Heap)) {
1305 log_debug(gc, verify)("Heap");
1306 heap()->verify(option);
1307 }
1308 if (should_verify_subset(Verify_SymbolTable)) {
1309 log_debug(gc, verify)("SymbolTable");
1310 SymbolTable::verify();
1311 }
1312 if (should_verify_subset(Verify_StringTable)) {
1313 log_debug(gc, verify)("StringTable");
1314 StringTable::verify();
1315 }
1316 if (should_verify_subset(Verify_CodeCache)) {
1317 log_debug(gc, verify)("CodeCache");
1318 CodeCache::verify();
1319 }
1320 if (should_verify_subset(Verify_SystemDictionary)) {
1321 log_debug(gc, verify)("SystemDictionary");
1322 SystemDictionary::verify();
1323 }
1324 if (should_verify_subset(Verify_ClassLoaderDataGraph)) {
1325 log_debug(gc, verify)("ClassLoaderDataGraph");
1326 ClassLoaderDataGraph::verify();
1327 }
1328 if (should_verify_subset(Verify_MetaspaceUtils)) {
1329 log_debug(gc, verify)("MetaspaceUtils");
1330 DEBUG_ONLY(MetaspaceUtils::verify();)
1331 }
1332 if (should_verify_subset(Verify_JNIHandles)) {
1333 log_debug(gc, verify)("JNIHandles");
1334 JNIHandles::verify();
1335 }
1336 if (should_verify_subset(Verify_CodeCacheOops)) {
1337 log_debug(gc, verify)("CodeCache Oops");
1338 CodeCache::verify_oops();
1339 }
1340 if (should_verify_subset(Verify_ResolvedMethodTable)) {
1341 log_debug(gc, verify)("ResolvedMethodTable Oops");
1342 ResolvedMethodTable::verify();
1343 }
1344 if (should_verify_subset(Verify_StringDedup)) {
1345 log_debug(gc, verify)("String Deduplication");
1346 StringDedup::verify();
1347 }
1348 }
1349
1350 static void log_cpu_time() {
1351 LogTarget(Info, cpu) cpuLog;
1352 if (!cpuLog.is_enabled()) {
1353 return;
1354 }
1355
1356 const double process_cpu_time = os::elapsed_process_cpu_time();
1357 if (process_cpu_time == 0 || process_cpu_time == -1) {
1358 // 0 can happen e.g. for short running processes with
1359 // low CPU utilization
1360 return;
1361 }
1362
1363 const double gc_threads_cpu_time = (double) CPUTimeUsage::GC::gc_threads() / NANOSECS_PER_SEC;
1364 const double gc_vm_thread_cpu_time = (double) CPUTimeUsage::GC::vm_thread() / NANOSECS_PER_SEC;
1365 const double gc_string_dedup_cpu_time = (double) CPUTimeUsage::GC::stringdedup() / NANOSECS_PER_SEC;
1366 const double gc_cpu_time = (double) gc_threads_cpu_time + gc_vm_thread_cpu_time + gc_string_dedup_cpu_time;
1367
1368 const double elasped_time = os::elapsedTime();
1369 const bool has_error = CPUTimeUsage::Error::has_error();
1370
1371 if (gc_cpu_time < process_cpu_time) {
1372 cpuLog.print("=== CPU time Statistics =============================================================");
1373 if (has_error) {
1374 cpuLog.print("WARNING: CPU time sampling reported errors, numbers may be unreliable");
1375 }
1376 cpuLog.print(" CPUs");
1377 cpuLog.print(" s %% utilized");
1378 cpuLog.print(" Process");
1379 cpuLog.print(" Total %30.4f %6.2f %8.1f", process_cpu_time, 100.0, process_cpu_time / elasped_time);
1380 cpuLog.print(" Garbage Collection %30.4f %6.2f %8.1f", gc_cpu_time, percent_of(gc_cpu_time, process_cpu_time), gc_cpu_time / elasped_time);
1381 cpuLog.print(" GC Threads %30.4f %6.2f %8.1f", gc_threads_cpu_time, percent_of(gc_threads_cpu_time, process_cpu_time), gc_threads_cpu_time / elasped_time);
1382 cpuLog.print(" VM Thread %30.4f %6.2f %8.1f", gc_vm_thread_cpu_time, percent_of(gc_vm_thread_cpu_time, process_cpu_time), gc_vm_thread_cpu_time / elasped_time);
1383
1384 if (UseStringDeduplication) {
1385 cpuLog.print(" String Deduplication %30.4f %6.2f %8.1f", gc_string_dedup_cpu_time, percent_of(gc_string_dedup_cpu_time, process_cpu_time), gc_string_dedup_cpu_time / elasped_time);
1386 }
1387 cpuLog.print("=====================================================================================");
1388 }
1389 }
1390
1391 void Universe::before_exit() {
1392 // Tell the GC that it is time to shutdown and to block requests for new GC pauses.
1393 heap()->initiate_shutdown();
1394
1395 // Log CPU time statistics before stopping the GC threads.
1396 log_cpu_time();
1397
1398 // Stop the GC threads.
1399 heap()->stop();
1400
1401 // Print GC/heap related information.
1402 Log(gc, exit) log;
1403 if (log.is_info()) {
1404 LogStream ls_info(log.info());
1405 Universe::print_on(&ls_info);
1406 if (log.is_trace()) {
1407 LogStream ls_trace(log.trace());
1408 MutexLocker mcld(ClassLoaderDataGraph_lock);
1409 ClassLoaderDataGraph::print_on(&ls_trace);
1410 }
1411 }
1412 }
1413
1414 #ifndef PRODUCT
1415 void Universe::calculate_verify_data(HeapWord* low_boundary, HeapWord* high_boundary) {
1416 assert(low_boundary < high_boundary, "bad interval");
1417
1418 // decide which low-order bits we require to be clear:
1419 size_t alignSize = MinObjAlignmentInBytes;
1420 size_t min_object_size = CollectedHeap::min_fill_size();
1421
1422 // make an inclusive limit:
1423 uintptr_t max = (uintptr_t)high_boundary - min_object_size*wordSize;
1424 uintptr_t min = (uintptr_t)low_boundary;
1425 assert(min < max, "bad interval");
1426 uintptr_t diff = max ^ min;
1427
1428 // throw away enough low-order bits to make the diff vanish
1429 uintptr_t mask = (uintptr_t)(-1);
1430 while ((mask & diff) != 0)
1431 mask <<= 1;
1432 uintptr_t bits = (min & mask);
1433 assert(bits == (max & mask), "correct mask");
1434 // check an intermediate value between min and max, just to make sure:
1435 assert(bits == ((min + (max-min)/2) & mask), "correct mask");
1436
1437 // require address alignment, too:
1438 mask |= (alignSize - 1);
1439
1440 if (!(_verify_oop_mask == 0 && _verify_oop_bits == (uintptr_t)-1)) {
1441 assert(_verify_oop_mask == mask && _verify_oop_bits == bits, "mask stability");
1442 }
1443 _verify_oop_mask = mask;
1444 _verify_oop_bits = bits;
1445 }
1446
1447 void Universe::set_verify_data(uintptr_t mask, uintptr_t bits) {
1448 _verify_oop_mask = mask;
1449 _verify_oop_bits = bits;
1450 }
1451
1452 // Oop verification (see MacroAssembler::verify_oop)
1453
1454 uintptr_t Universe::verify_oop_mask() {
1455 return _verify_oop_mask;
1456 }
1457
1458 uintptr_t Universe::verify_oop_bits() {
1459 return _verify_oop_bits;
1460 }
1461
1462 uintptr_t Universe::verify_mark_mask() {
1463 return markWord::lock_mask_in_place;
1464 }
1465
1466 uintptr_t Universe::verify_mark_bits() {
1467 intptr_t mask = verify_mark_mask();
1468 intptr_t bits = (intptr_t)markWord::prototype().value();
1469 assert((bits & ~mask) == 0, "no stray header bits");
1470 return bits;
1471 }
1472 #endif // PRODUCT
1473
1474 #ifdef ASSERT
1475 // Release dummy object(s) at bottom of heap
1476 bool Universe::release_fullgc_alot_dummy() {
1477 MutexLocker ml(FullGCALot_lock, Mutex::_no_safepoint_check_flag);
1478 objArrayOop fullgc_alot_dummy_array = (objArrayOop)_fullgc_alot_dummy_array.resolve();
1479 if (fullgc_alot_dummy_array != nullptr) {
1480 if (_fullgc_alot_dummy_next >= fullgc_alot_dummy_array->length()) {
1481 // No more dummies to release, release entire array instead
1482 _fullgc_alot_dummy_array.release(Universe::vm_global());
1483 _fullgc_alot_dummy_array = OopHandle(); // null out OopStorage pointer.
1484 return false;
1485 }
1486
1487 // Release dummy at bottom of old generation
1488 fullgc_alot_dummy_array->obj_at_put(_fullgc_alot_dummy_next++, nullptr);
1489 }
1490 return true;
1491 }
1492
1493 bool Universe::is_stw_gc_active() {
1494 return heap()->is_stw_gc_active();
1495 }
1496
1497 bool Universe::is_in_heap(const void* p) {
1498 return heap()->is_in(p);
1499 }
1500
1501 #endif // ASSERT