1 /*
2 * Copyright (c) 1997, 2024, Oracle and/or its affiliates. All rights reserved.
3 * Copyright (c) 2021, Azul Systems, Inc. All rights reserved.
4 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
5 *
6 * This code is free software; you can redistribute it and/or modify it
7 * under the terms of the GNU General Public License version 2 only, as
8 * published by the Free Software Foundation.
9 *
10 * This code is distributed in the hope that it will be useful, but WITHOUT
11 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
12 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
13 * version 2 for more details (a copy is included in the LICENSE file that
14 * accompanied this code).
15 *
16 * You should have received a copy of the GNU General Public License version
17 * 2 along with this work; if not, write to the Free Software Foundation,
18 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
19 *
20 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
21 * or visit www.oracle.com if you need additional information or have any
22 * questions.
23 *
24 */
25
26 #include "precompiled.hpp"
27 #include "cds/cds_globals.hpp"
28 #include "cds/cdsConfig.hpp"
29 #include "cds/metaspaceShared.hpp"
30 #include "classfile/classLoader.hpp"
31 #include "classfile/javaClasses.hpp"
32 #include "classfile/javaThreadStatus.hpp"
33 #include "classfile/systemDictionary.hpp"
34 #include "classfile/vmClasses.hpp"
35 #include "classfile/vmSymbols.hpp"
36 #include "compiler/compileBroker.hpp"
37 #include "compiler/compileTask.hpp"
38 #include "compiler/compilerThread.hpp"
39 #include "gc/shared/barrierSet.hpp"
40 #include "gc/shared/barrierSetNMethod.hpp"
41 #include "gc/shared/gcVMOperations.hpp"
42 #include "gc/shared/oopStorage.hpp"
43 #include "gc/shared/oopStorageSet.hpp"
44 #include "gc/shared/stringdedup/stringDedup.hpp"
45 #include "jfr/jfrEvents.hpp"
46 #include "jvm.h"
47 #include "jvmtifiles/jvmtiEnv.hpp"
48 #include "logging/log.hpp"
49 #include "logging/logAsyncWriter.hpp"
50 #include "logging/logConfiguration.hpp"
51 #include "memory/allocation.inline.hpp"
52 #include "memory/iterator.hpp"
53 #include "memory/oopFactory.hpp"
54 #include "memory/resourceArea.hpp"
55 #include "memory/universe.hpp"
56 #include "nmt/memTracker.hpp"
57 #include "oops/instanceKlass.hpp"
58 #include "oops/klass.inline.hpp"
59 #include "oops/oop.inline.hpp"
60 #include "oops/symbol.hpp"
61 #include "prims/jvm_misc.hpp"
62 #include "prims/jvmtiAgentList.hpp"
63 #include "prims/jvmtiEnvBase.hpp"
64 #include "runtime/arguments.hpp"
65 #include "runtime/fieldDescriptor.inline.hpp"
66 #include "runtime/flags/jvmFlagLimit.hpp"
67 #include "runtime/globals.hpp"
68 #include "runtime/globals_extension.hpp"
69 #include "runtime/handles.inline.hpp"
70 #include "runtime/interfaceSupport.inline.hpp"
71 #include "runtime/java.hpp"
72 #include "runtime/javaCalls.hpp"
73 #include "runtime/javaThread.inline.hpp"
74 #include "runtime/jniHandles.inline.hpp"
75 #include "runtime/jniPeriodicChecker.hpp"
76 #include "runtime/lockStack.inline.hpp"
77 #include "runtime/monitorDeflationThread.hpp"
78 #include "runtime/mutexLocker.hpp"
79 #include "runtime/nonJavaThread.hpp"
80 #include "runtime/objectMonitor.inline.hpp"
81 #include "runtime/osThread.hpp"
82 #include "runtime/safepoint.hpp"
83 #include "runtime/safepointMechanism.inline.hpp"
84 #include "runtime/safepointVerifiers.hpp"
85 #include "runtime/serviceThread.hpp"
86 #include "runtime/sharedRuntime.hpp"
87 #include "runtime/stackWatermarkSet.inline.hpp"
88 #include "runtime/statSampler.hpp"
89 #include "runtime/stubCodeGenerator.hpp"
90 #include "runtime/thread.inline.hpp"
91 #include "runtime/threadSMR.inline.hpp"
92 #include "runtime/threads.hpp"
93 #include "runtime/timer.hpp"
94 #include "runtime/timerTrace.hpp"
95 #include "runtime/trimNativeHeap.hpp"
96 #include "runtime/vmOperations.hpp"
97 #include "runtime/vm_version.hpp"
98 #include "services/attachListener.hpp"
99 #include "services/management.hpp"
100 #include "services/threadIdTable.hpp"
101 #include "services/threadService.hpp"
102 #include "utilities/dtrace.hpp"
103 #include "utilities/events.hpp"
104 #include "utilities/macros.hpp"
105 #include "utilities/vmError.hpp"
106 #if INCLUDE_JVMCI
107 #include "jvmci/jvmci.hpp"
108 #include "jvmci/jvmciEnv.hpp"
109 #endif
110 #ifdef COMPILER2
111 #include "opto/idealGraphPrinter.hpp"
112 #endif
113 #if INCLUDE_JFR
114 #include "jfr/jfr.hpp"
115 #endif
116
117 // Initialization after module runtime initialization
118 void universe_post_module_init(); // must happen after call_initPhase2
119
120
121 static void initialize_class(Symbol* class_name, TRAPS) {
122 Klass* klass = SystemDictionary::resolve_or_fail(class_name, true, CHECK);
123 InstanceKlass::cast(klass)->initialize(CHECK);
124 }
125
126
127 // Creates the initial ThreadGroup
128 static Handle create_initial_thread_group(TRAPS) {
129 Handle system_instance = JavaCalls::construct_new_instance(
130 vmClasses::ThreadGroup_klass(),
131 vmSymbols::void_method_signature(),
132 CHECK_NH);
133 Universe::set_system_thread_group(system_instance());
134
135 Handle string = java_lang_String::create_from_str("main", CHECK_NH);
136 Handle main_instance = JavaCalls::construct_new_instance(
137 vmClasses::ThreadGroup_klass(),
138 vmSymbols::threadgroup_string_void_signature(),
139 system_instance,
140 string,
141 CHECK_NH);
142 return main_instance;
143 }
144
145 // Creates the initial Thread, and sets it to running.
146 static void create_initial_thread(Handle thread_group, JavaThread* thread,
147 TRAPS) {
148 InstanceKlass* ik = vmClasses::Thread_klass();
149 assert(ik->is_initialized(), "must be");
150 instanceHandle thread_oop = ik->allocate_instance_handle(CHECK);
151
152 // Cannot use JavaCalls::construct_new_instance because the java.lang.Thread
153 // constructor calls Thread.current(), which must be set here for the
154 // initial thread.
155 java_lang_Thread::set_thread(thread_oop(), thread);
156 thread->set_threadOopHandles(thread_oop());
157
158 Handle string = java_lang_String::create_from_str("main", CHECK);
159
160 JavaValue result(T_VOID);
161 JavaCalls::call_special(&result, thread_oop,
162 ik,
163 vmSymbols::object_initializer_name(),
164 vmSymbols::threadgroup_string_void_signature(),
165 thread_group,
166 string,
167 CHECK);
168
169 assert(thread->lock_id() == ThreadIdentifier::initial(), "invariant");
170
171 // Set thread status to running since main thread has
172 // been started and running.
173 java_lang_Thread::set_thread_status(thread_oop(),
174 JavaThreadStatus::RUNNABLE);
175 }
176
177 // Extract version and vendor specific information from
178 // java.lang.VersionProps fields.
179 // Returned char* is allocated in the thread's resource area
180 // so must be copied for permanency.
181 static const char* get_java_version_info(InstanceKlass* ik,
182 Symbol* field_name) {
183 fieldDescriptor fd;
184 bool found = ik != nullptr &&
185 ik->find_local_field(field_name,
186 vmSymbols::string_signature(), &fd);
187 if (found) {
188 oop name_oop = ik->java_mirror()->obj_field(fd.offset());
189 if (name_oop == nullptr) {
190 return nullptr;
191 }
192 const char* name = java_lang_String::as_utf8_string(name_oop);
193 return name;
194 } else {
195 return nullptr;
196 }
197 }
198
199 // ======= Threads ========
200
201 // The Threads class links together all active threads, and provides
202 // operations over all threads. It is protected by the Threads_lock,
203 // which is also used in other global contexts like safepointing.
204 // ThreadsListHandles are used to safely perform operations on one
205 // or more threads without the risk of the thread exiting during the
206 // operation.
207 //
208 // Note: The Threads_lock is currently more widely used than we
209 // would like. We are actively migrating Threads_lock uses to other
210 // mechanisms in order to reduce Threads_lock contention.
211
212 int Threads::_number_of_threads = 0;
213 int Threads::_number_of_non_daemon_threads = 0;
214 int Threads::_return_code = 0;
215 uintx Threads::_thread_claim_token = 1; // Never zero.
216
217 #ifdef ASSERT
218 bool Threads::_vm_complete = false;
219 #endif
220
221 // General purpose hook into Java code, run once when the VM is initialized.
222 // The Java library method itself may be changed independently from the VM.
223 static void call_postVMInitHook(TRAPS) {
224 Klass* klass = SystemDictionary::resolve_or_null(vmSymbols::jdk_internal_vm_PostVMInitHook(), THREAD);
225 if (klass != nullptr) {
226 JavaValue result(T_VOID);
227 JavaCalls::call_static(&result, klass, vmSymbols::run_method_name(),
228 vmSymbols::void_method_signature(),
229 CHECK);
230 }
231 }
232
233 // All NonJavaThreads (i.e., every non-JavaThread in the system).
234 void Threads::non_java_threads_do(ThreadClosure* tc) {
235 NoSafepointVerifier nsv;
236 for (NonJavaThread::Iterator njti; !njti.end(); njti.step()) {
237 tc->do_thread(njti.current());
238 }
239 }
240
241 // All JavaThreads
242 #define ALL_JAVA_THREADS(X) \
243 for (JavaThread* X : *ThreadsSMRSupport::get_java_thread_list())
244
245 // All JavaThreads
246 void Threads::java_threads_do(ThreadClosure* tc) {
247 assert_locked_or_safepoint(Threads_lock);
248 // ALL_JAVA_THREADS iterates through all JavaThreads.
249 ALL_JAVA_THREADS(p) {
250 tc->do_thread(p);
251 }
252 }
253
254 // All JavaThreads + all non-JavaThreads (i.e., every thread in the system).
255 void Threads::threads_do(ThreadClosure* tc) {
256 assert_locked_or_safepoint(Threads_lock);
257 java_threads_do(tc);
258 non_java_threads_do(tc);
259 }
260
261 void Threads::possibly_parallel_threads_do(bool is_par, ThreadClosure* tc) {
262 assert_at_safepoint();
263
264 uintx claim_token = Threads::thread_claim_token();
265 ALL_JAVA_THREADS(p) {
266 if (p->claim_threads_do(is_par, claim_token)) {
267 tc->do_thread(p);
268 }
269 }
270 for (NonJavaThread::Iterator njti; !njti.end(); njti.step()) {
271 Thread* current = njti.current();
272 if (current->claim_threads_do(is_par, claim_token)) {
273 tc->do_thread(current);
274 }
275 }
276 }
277
278 // The system initialization in the library has three phases.
279 //
280 // Phase 1: java.lang.System class initialization
281 // java.lang.System is a primordial class loaded and initialized
282 // by the VM early during startup. java.lang.System.<clinit>
283 // only does registerNatives and keeps the rest of the class
284 // initialization work later until thread initialization completes.
285 //
286 // System.initPhase1 initializes the system properties, the static
287 // fields in, out, and err. Set up java signal handlers, OS-specific
288 // system settings, and thread group of the main thread.
289 static void call_initPhase1(TRAPS) {
290 Klass* klass = vmClasses::System_klass();
291 JavaValue result(T_VOID);
292 JavaCalls::call_static(&result, klass, vmSymbols::initPhase1_name(),
293 vmSymbols::void_method_signature(), CHECK);
294 }
295
296 // Phase 2. Module system initialization
297 // This will initialize the module system. Only java.base classes
298 // can be loaded until phase 2 completes.
299 //
300 // Call System.initPhase2 after the compiler initialization and jsr292
301 // classes get initialized because module initialization runs a lot of java
302 // code, that for performance reasons, should be compiled. Also, this will
303 // enable the startup code to use lambda and other language features in this
304 // phase and onward.
305 //
306 // After phase 2, The VM will begin search classes from -Xbootclasspath/a.
307 static void call_initPhase2(TRAPS) {
308 TraceTime timer("Initialize module system", TRACETIME_LOG(Info, startuptime));
309
310 Klass* klass = vmClasses::System_klass();
311
312 JavaValue result(T_INT);
313 JavaCallArguments args;
314 args.push_int(DisplayVMOutputToStderr);
315 args.push_int(log_is_enabled(Debug, init)); // print stack trace if exception thrown
316 JavaCalls::call_static(&result, klass, vmSymbols::initPhase2_name(),
317 vmSymbols::boolean_boolean_int_signature(), &args, CHECK);
318 if (result.get_jint() != JNI_OK) {
319 vm_exit_during_initialization(); // no message or exception
320 }
321
322 universe_post_module_init();
323 }
324
325 // Phase 3. final setup - set security manager, system class loader and TCCL
326 //
327 // This will instantiate and set the security manager, set the system class
328 // loader as well as the thread context class loader. The security manager
329 // and system class loader may be a custom class loaded from -Xbootclasspath/a,
330 // other modules or the application's classpath.
331 static void call_initPhase3(TRAPS) {
332 Klass* klass = vmClasses::System_klass();
333 JavaValue result(T_VOID);
334 JavaCalls::call_static(&result, klass, vmSymbols::initPhase3_name(),
335 vmSymbols::void_method_signature(), CHECK);
336 }
337
338 void Threads::initialize_java_lang_classes(JavaThread* main_thread, TRAPS) {
339 TraceTime timer("Initialize java.lang classes", TRACETIME_LOG(Info, startuptime));
340
341 initialize_class(vmSymbols::java_lang_String(), CHECK);
342
343 // Inject CompactStrings value after the static initializers for String ran.
344 java_lang_String::set_compact_strings(CompactStrings);
345
346 // Initialize java_lang.System (needed before creating the thread)
347 initialize_class(vmSymbols::java_lang_System(), CHECK);
348 // The VM creates & returns objects of this class. Make sure it's initialized.
349 initialize_class(vmSymbols::java_lang_Class(), CHECK);
350 initialize_class(vmSymbols::java_lang_ThreadGroup(), CHECK);
351 Handle thread_group = create_initial_thread_group(CHECK);
352 Universe::set_main_thread_group(thread_group());
353 initialize_class(vmSymbols::java_lang_Thread(), CHECK);
354 create_initial_thread(thread_group, main_thread, CHECK);
355
356 // The VM creates objects of this class.
357 initialize_class(vmSymbols::java_lang_Module(), CHECK);
358
359 #ifdef ASSERT
360 InstanceKlass *k = vmClasses::UnsafeConstants_klass();
361 assert(k->is_not_initialized(), "UnsafeConstants should not already be initialized");
362 #endif
363
364 // initialize the hardware-specific constants needed by Unsafe
365 initialize_class(vmSymbols::jdk_internal_misc_UnsafeConstants(), CHECK);
366 jdk_internal_misc_UnsafeConstants::set_unsafe_constants();
367
368 // The VM preresolves methods to these classes. Make sure that they get initialized
369 initialize_class(vmSymbols::java_lang_reflect_Method(), CHECK);
370 initialize_class(vmSymbols::java_lang_ref_Finalizer(), CHECK);
371
372 // Phase 1 of the system initialization in the library, java.lang.System class initialization
373 call_initPhase1(CHECK);
374
375 // Get the Java runtime name, version, and vendor info after java.lang.System is initialized.
376 // Some values are actually configure-time constants but some can be set via the jlink tool and
377 // so must be read dynamically. We treat them all the same.
378 InstanceKlass* ik = SystemDictionary::find_instance_klass(THREAD, vmSymbols::java_lang_VersionProps(),
379 Handle(), Handle());
380 {
381 ResourceMark rm(main_thread);
382 JDK_Version::set_java_version(get_java_version_info(ik, vmSymbols::java_version_name()));
383
384 JDK_Version::set_runtime_name(get_java_version_info(ik, vmSymbols::java_runtime_name_name()));
385
386 JDK_Version::set_runtime_version(get_java_version_info(ik, vmSymbols::java_runtime_version_name()));
387
388 JDK_Version::set_runtime_vendor_version(get_java_version_info(ik, vmSymbols::java_runtime_vendor_version_name()));
389
390 JDK_Version::set_runtime_vendor_vm_bug_url(get_java_version_info(ik, vmSymbols::java_runtime_vendor_vm_bug_url_name()));
391 }
392
393 // an instance of OutOfMemory exception has been allocated earlier
394 initialize_class(vmSymbols::java_lang_OutOfMemoryError(), CHECK);
395 initialize_class(vmSymbols::java_lang_NullPointerException(), CHECK);
396 initialize_class(vmSymbols::java_lang_ClassCastException(), CHECK);
397 initialize_class(vmSymbols::java_lang_ArrayStoreException(), CHECK);
398 initialize_class(vmSymbols::java_lang_ArithmeticException(), CHECK);
399 initialize_class(vmSymbols::java_lang_ArrayIndexOutOfBoundsException(), CHECK);
400 initialize_class(vmSymbols::java_lang_StackOverflowError(), CHECK);
401 initialize_class(vmSymbols::java_lang_IllegalMonitorStateException(), CHECK);
402 initialize_class(vmSymbols::java_lang_IllegalArgumentException(), CHECK);
403 }
404
405 void Threads::initialize_jsr292_core_classes(TRAPS) {
406 TraceTime timer("Initialize java.lang.invoke classes", TRACETIME_LOG(Info, startuptime));
407
408 initialize_class(vmSymbols::java_lang_invoke_MethodHandle(), CHECK);
409 initialize_class(vmSymbols::java_lang_invoke_ResolvedMethodName(), CHECK);
410 initialize_class(vmSymbols::java_lang_invoke_MemberName(), CHECK);
411 initialize_class(vmSymbols::java_lang_invoke_MethodHandleNatives(), CHECK);
412 }
413
414 jint Threads::create_vm(JavaVMInitArgs* args, bool* canTryAgain) {
415 extern void JDK_Version_init();
416
417 // Preinitialize version info.
418 VM_Version::early_initialize();
419
420 // Check version
421 if (!is_supported_jni_version(args->version)) return JNI_EVERSION;
422
423 // Initialize library-based TLS
424 ThreadLocalStorage::init();
425
426 // Initialize the output stream module
427 ostream_init();
428
429 // Process java launcher properties.
430 Arguments::process_sun_java_launcher_properties(args);
431
432 // Initialize the os module
433 os::init();
434
435 MACOS_AARCH64_ONLY(os::current_thread_enable_wx(WXWrite));
436
437 // Record VM creation timing statistics
438 TraceVmCreationTime create_vm_timer;
439 create_vm_timer.start();
440
441 // Initialize system properties.
442 Arguments::init_system_properties();
443
444 // So that JDK version can be used as a discriminator when parsing arguments
445 JDK_Version_init();
446
447 // Update/Initialize System properties after JDK version number is known
448 Arguments::init_version_specific_system_properties();
449
450 // Make sure to initialize log configuration *before* parsing arguments
451 LogConfiguration::initialize(create_vm_timer.begin_time());
452
453 // Parse arguments
454 // Note: this internally calls os::init_container_support()
455 jint parse_result = Arguments::parse(args);
456 if (parse_result != JNI_OK) return parse_result;
457
458 // Initialize NMT right after argument parsing to keep the pre-NMT-init window small.
459 MemTracker::initialize();
460
461 os::init_before_ergo();
462
463 jint ergo_result = Arguments::apply_ergo();
464 if (ergo_result != JNI_OK) return ergo_result;
465
466 // Final check of all ranges after ergonomics which may change values.
467 if (!JVMFlagLimit::check_all_ranges()) {
468 return JNI_EINVAL;
469 }
470
471 // Final check of all 'AfterErgo' constraints after ergonomics which may change values.
472 bool constraint_result = JVMFlagLimit::check_all_constraints(JVMFlagConstraintPhase::AfterErgo);
473 if (!constraint_result) {
474 return JNI_EINVAL;
475 }
476
477 if (PauseAtStartup) {
478 os::pause();
479 }
480
481 HOTSPOT_VM_INIT_BEGIN();
482
483 // Timing (must come after argument parsing)
484 TraceTime timer("Create VM", TRACETIME_LOG(Info, startuptime));
485
486 // Initialize the os module after parsing the args
487 jint os_init_2_result = os::init_2();
488 if (os_init_2_result != JNI_OK) return os_init_2_result;
489
490 #ifdef CAN_SHOW_REGISTERS_ON_ASSERT
491 // Initialize assert poison page mechanism.
492 if (ShowRegistersOnAssert) {
493 initialize_assert_poison();
494 }
495 #endif // CAN_SHOW_REGISTERS_ON_ASSERT
496
497 SafepointMechanism::initialize();
498
499 jint adjust_after_os_result = Arguments::adjust_after_os();
500 if (adjust_after_os_result != JNI_OK) return adjust_after_os_result;
501
502 // Initialize output stream logging
503 ostream_init_log();
504
505 // Launch -agentlib/-agentpath and converted -Xrun agents
506 JvmtiAgentList::load_agents();
507
508 // Initialize Threads state
509 _number_of_threads = 0;
510 _number_of_non_daemon_threads = 0;
511
512 // Initialize global data structures and create system classes in heap
513 vm_init_globals();
514
515 #if INCLUDE_JVMCI
516 if (JVMCICounterSize > 0) {
517 JavaThread::_jvmci_old_thread_counters = NEW_C_HEAP_ARRAY(jlong, JVMCICounterSize, mtJVMCI);
518 memset(JavaThread::_jvmci_old_thread_counters, 0, sizeof(jlong) * JVMCICounterSize);
519 } else {
520 JavaThread::_jvmci_old_thread_counters = nullptr;
521 }
522 #endif // INCLUDE_JVMCI
523
524 // Initialize OopStorage for threadObj
525 JavaThread::_thread_oop_storage = OopStorageSet::create_strong("Thread OopStorage", mtThread);
526
527 // Attach the main thread to this os thread
528 JavaThread* main_thread = new JavaThread();
529 main_thread->set_thread_state(_thread_in_vm);
530 main_thread->initialize_thread_current();
531 // must do this before set_active_handles
532 main_thread->record_stack_base_and_size();
533 main_thread->register_thread_stack_with_NMT();
534 main_thread->set_active_handles(JNIHandleBlock::allocate_block());
535 MACOS_AARCH64_ONLY(main_thread->init_wx());
536
537 // Set the lock_id now since we will run Java code before the Thread instance
538 // is even created. The same value will be assigned to the Thread instance on init.
539 main_thread->set_lock_id(ThreadIdentifier::next());
540 assert(main_thread->lock_id() == ThreadIdentifier::initial(), "invariant");
541
542 if (!main_thread->set_as_starting_thread()) {
543 vm_shutdown_during_initialization(
544 "Failed necessary internal allocation. Out of swap space");
545 main_thread->smr_delete();
546 *canTryAgain = false; // don't let caller call JNI_CreateJavaVM again
547 return JNI_ENOMEM;
548 }
549
550 // Enable guard page *after* os::create_main_thread(), otherwise it would
551 // crash Linux VM, see notes in os_linux.cpp.
552 main_thread->stack_overflow_state()->create_stack_guard_pages();
553
554 // Initialize Java-Level synchronization subsystem
555 ObjectMonitor::Initialize();
556 ObjectSynchronizer::initialize();
557
558 // Initialize global modules
559 jint status = init_globals();
560 if (status != JNI_OK) {
561 main_thread->smr_delete();
562 *canTryAgain = false; // don't let caller call JNI_CreateJavaVM again
563 return status;
564 }
565
566 // Create WatcherThread as soon as we can since we need it in case
567 // of hangs during error reporting.
568 WatcherThread::start();
569
570 // Add main_thread to threads list to finish barrier setup with
571 // on_thread_attach. Should be before starting to build Java objects in
572 // init_globals2, which invokes barriers.
573 {
574 MutexLocker mu(Threads_lock);
575 Threads::add(main_thread);
576 }
577
578 status = init_globals2();
579 if (status != JNI_OK) {
580 Threads::remove(main_thread, false);
581 // It is possible that we managed to fully initialize Universe but have then
582 // failed by throwing an exception. In that case our caller JNI_CreateJavaVM
583 // will want to report it, so we can't delete the main thread.
584 if (!main_thread->has_pending_exception()) {
585 main_thread->smr_delete();
586 }
587 *canTryAgain = false; // don't let caller call JNI_CreateJavaVM again
588 return status;
589 }
590
591 ObjectMonitor::Initialize2();
592
593 JFR_ONLY(Jfr::on_create_vm_1();)
594
595 // Should be done after the heap is fully created
596 main_thread->cache_global_variables();
597
598 // Any JVMTI raw monitors entered in onload will transition into
599 // real raw monitor. VM is setup enough here for raw monitor enter.
600 JvmtiExport::transition_pending_onload_raw_monitors();
601
602 // Create the VMThread
603 { TraceTime timer("Start VMThread", TRACETIME_LOG(Info, startuptime));
604
605 VMThread::create();
606 VMThread* vmthread = VMThread::vm_thread();
607
608 if (!os::create_thread(vmthread, os::vm_thread)) {
609 vm_exit_during_initialization("Cannot create VM thread. "
610 "Out of system resources.");
611 }
612
613 // Wait for the VM thread to become ready, and VMThread::run to initialize
614 // Monitors can have spurious returns, must always check another state flag
615 {
616 MonitorLocker ml(Notify_lock);
617 os::start_thread(vmthread);
618 while (!vmthread->is_running()) {
619 ml.wait();
620 }
621 }
622 }
623
624 assert(Universe::is_fully_initialized(), "not initialized");
625 if (VerifyDuringStartup) {
626 // Make sure we're starting with a clean slate.
627 VM_Verify verify_op;
628 VMThread::execute(&verify_op);
629 }
630
631 // We need this to update the java.vm.info property in case any flags used
632 // to initially define it have been changed. This is needed for both CDS
633 // since UseSharedSpaces may be changed after java.vm.info
634 // is initially computed. See Abstract_VM_Version::vm_info_string().
635 // This update must happen before we initialize the java classes, but
636 // after any initialization logic that might modify the flags.
637 Arguments::update_vm_info_property(VM_Version::vm_info_string());
638
639 JavaThread* THREAD = JavaThread::current(); // For exception macros.
640 HandleMark hm(THREAD);
641
642 // Always call even when there are not JVMTI environments yet, since environments
643 // may be attached late and JVMTI must track phases of VM execution
644 JvmtiExport::enter_early_start_phase();
645
646 // Notify JVMTI agents that VM has started (JNI is up) - nop if no agents.
647 JvmtiExport::post_early_vm_start();
648
649 // Launch -Xrun agents early if EagerXrunInit is set
650 if (EagerXrunInit) {
651 JvmtiAgentList::load_xrun_agents();
652 }
653
654 initialize_java_lang_classes(main_thread, CHECK_JNI_ERR);
655
656 quicken_jni_functions();
657
658 // No more stub generation allowed after that point.
659 StubCodeDesc::freeze();
660
661 // Set flag that basic initialization has completed. Used by exceptions and various
662 // debug stuff, that does not work until all basic classes have been initialized.
663 set_init_completed();
664
665 LogConfiguration::post_initialize();
666 Metaspace::post_initialize();
667 MutexLockerImpl::post_initialize();
668
669 HOTSPOT_VM_INIT_END();
670
671 // record VM initialization completion time
672 #if INCLUDE_MANAGEMENT
673 Management::record_vm_init_completed();
674 #endif // INCLUDE_MANAGEMENT
675
676 log_info(os)("Initialized VM with process ID %d", os::current_process_id());
677
678 if (!FLAG_IS_DEFAULT(CreateCoredumpOnCrash) && CreateCoredumpOnCrash) {
679 char buffer[2*JVM_MAXPATHLEN];
680 os::check_core_dump_prerequisites(buffer, sizeof(buffer), true);
681 }
682
683 // Signal Dispatcher needs to be started before VMInit event is posted
684 os::initialize_jdk_signal_support(CHECK_JNI_ERR);
685
686 // Start Attach Listener if +StartAttachListener or it can't be started lazily
687 if (!DisableAttachMechanism) {
688 AttachListener::vm_start();
689 if (StartAttachListener || AttachListener::init_at_startup()) {
690 AttachListener::init();
691 }
692 }
693
694 // Launch -Xrun agents if EagerXrunInit is not set.
695 if (!EagerXrunInit) {
696 JvmtiAgentList::load_xrun_agents();
697 }
698
699 Arena::start_chunk_pool_cleaner_task();
700
701 // Start the service thread
702 // The service thread enqueues JVMTI deferred events and does various hashtable
703 // and other cleanups. Needs to start before the compilers start posting events.
704 ServiceThread::initialize();
705
706 // Start the monitor deflation thread:
707 MonitorDeflationThread::initialize();
708
709 // initialize compiler(s)
710 #if defined(COMPILER1) || COMPILER2_OR_JVMCI
711 bool init_compilation = true;
712 #if INCLUDE_JVMCI
713 bool force_JVMCI_initialization = false;
714 if (EnableJVMCI) {
715 // Initialize JVMCI eagerly when it is explicitly requested.
716 // Or when JVMCILibDumpJNIConfig or JVMCIPrintProperties is enabled.
717 force_JVMCI_initialization = EagerJVMCI || JVMCIPrintProperties || JVMCILibDumpJNIConfig;
718 if (!force_JVMCI_initialization && UseJVMCICompiler && !UseJVMCINativeLibrary && (!UseInterpreter || !BackgroundCompilation)) {
719 // Force initialization of jarjvmci otherwise requests for blocking
720 // compilations will not actually block until jarjvmci is initialized.
721 force_JVMCI_initialization = true;
722 }
723 if (JVMCIPrintProperties || JVMCILibDumpJNIConfig) {
724 // Both JVMCILibDumpJNIConfig and JVMCIPrintProperties exit the VM
725 // so compilation should be disabled. This prevents dumping or
726 // printing from happening more than once.
727 init_compilation = false;
728 }
729 }
730 #endif
731 if (init_compilation) {
732 CompileBroker::compilation_init(CHECK_JNI_ERR);
733 }
734 #endif
735
736 // Start string deduplication thread if requested.
737 if (StringDedup::is_enabled()) {
738 StringDedup::start();
739 }
740
741 // Pre-initialize some JSR292 core classes to avoid deadlock during class loading.
742 // It is done after compilers are initialized, because otherwise compilations of
743 // signature polymorphic MH intrinsics can be missed
744 // (see SystemDictionary::find_method_handle_intrinsic).
745 initialize_jsr292_core_classes(CHECK_JNI_ERR);
746
747 // This will initialize the module system. Only java.base classes can be
748 // loaded until phase 2 completes
749 call_initPhase2(CHECK_JNI_ERR);
750
751 JFR_ONLY(Jfr::on_create_vm_2();)
752
753 // Always call even when there are not JVMTI environments yet, since environments
754 // may be attached late and JVMTI must track phases of VM execution
755 JvmtiExport::enter_start_phase();
756
757 // Notify JVMTI agents that VM has started (JNI is up) - nop if no agents.
758 JvmtiExport::post_vm_start();
759
760 // Final system initialization including security manager and system class loader
761 call_initPhase3(CHECK_JNI_ERR);
762
763 // cache the system and platform class loaders
764 SystemDictionary::compute_java_loaders(CHECK_JNI_ERR);
765
766 if (Continuations::enabled()) {
767 // Initialize Continuation class now so that failure to create enterSpecial/doYield
768 // special nmethods due to limited CodeCache size can be treated as a fatal error at
769 // startup with the proper message that CodeCache size is too small.
770 initialize_class(vmSymbols::jdk_internal_vm_Continuation(), CHECK_JNI_ERR);
771 }
772
773 #if INCLUDE_CDS
774 // capture the module path info from the ModuleEntryTable
775 ClassLoader::initialize_module_path(THREAD);
776 if (HAS_PENDING_EXCEPTION) {
777 java_lang_Throwable::print(PENDING_EXCEPTION, tty);
778 vm_exit_during_initialization("ClassLoader::initialize_module_path() failed unexpectedly");
779 }
780 #endif
781
782 #if INCLUDE_JVMCI
783 if (force_JVMCI_initialization) {
784 JVMCI::initialize_compiler(CHECK_JNI_ERR);
785 }
786 #endif
787
788 if (NativeHeapTrimmer::enabled()) {
789 NativeHeapTrimmer::initialize();
790 }
791
792 // Always call even when there are not JVMTI environments yet, since environments
793 // may be attached late and JVMTI must track phases of VM execution
794 JvmtiExport::enter_live_phase();
795
796 // Make perfmemory accessible
797 PerfMemory::set_accessible(true);
798
799 // Notify JVMTI agents that VM initialization is complete - nop if no agents.
800 JvmtiExport::post_vm_initialized();
801
802 JFR_ONLY(Jfr::on_create_vm_3();)
803
804 #if INCLUDE_MANAGEMENT
805 Management::initialize(THREAD);
806
807 if (HAS_PENDING_EXCEPTION) {
808 // management agent fails to start possibly due to
809 // configuration problem and is responsible for printing
810 // stack trace if appropriate. Simply exit VM.
811 vm_exit(1);
812 }
813 #endif // INCLUDE_MANAGEMENT
814
815 StatSampler::engage();
816 if (CheckJNICalls) JniPeriodicChecker::engage();
817
818 call_postVMInitHook(THREAD);
819 // The Java side of PostVMInitHook.run must deal with all
820 // exceptions and provide means of diagnosis.
821 if (HAS_PENDING_EXCEPTION) {
822 CLEAR_PENDING_EXCEPTION;
823 }
824
825 // Let WatcherThread run all registered periodic tasks now.
826 // NOTE: All PeriodicTasks should be registered by now. If they
827 // aren't, late joiners might appear to start slowly (we might
828 // take a while to process their first tick).
829 WatcherThread::run_all_tasks();
830
831 create_vm_timer.end();
832 #ifdef ASSERT
833 _vm_complete = true;
834 #endif
835
836 if (CDSConfig::is_dumping_static_archive()) {
837 MetaspaceShared::preload_and_dump(CHECK_JNI_ERR);
838 }
839
840 if (log_is_enabled(Info, perf, class, link)) {
841 LogStreamHandle(Info, perf, class, link) log;
842 log.print_cr("At VM initialization completion:");
843 ClassLoader::print_counters(&log);
844 }
845
846 return JNI_OK;
847 }
848
849 // Threads::destroy_vm() is normally called from jni_DestroyJavaVM() when
850 // the program falls off the end of main(). Another VM exit path is through
851 // vm_exit(), when the program calls System.exit() to return a value, or when
852 // there is a serious error in VM.
853 // These two separate shutdown paths are not exactly the same, but they share
854 // Shutdown.shutdown() at Java level and before_exit() and VM_Exit op at VM level.
855 //
856 // Shutdown sequence:
857 // + Shutdown native memory tracking if it is on
858 // + Wait until we are the last non-daemon thread to execute
859 // <-- every thing is still working at this moment -->
860 // + Call java.lang.Shutdown.shutdown(), which will invoke Java level
861 // shutdown hooks
862 // + Call before_exit(), prepare for VM exit
863 // > run VM level shutdown hooks (they are registered through JVM_OnExit(),
864 // currently the only user of this mechanism is File.deleteOnExit())
865 // > stop StatSampler, watcher thread,
866 // post thread end and vm death events to JVMTI,
867 // stop signal thread
868 // + Call JavaThread::exit(), it will:
869 // > release JNI handle blocks, remove stack guard pages
870 // > remove this thread from Threads list
871 // <-- no more Java code from this thread after this point -->
872 // + Stop VM thread, it will bring the remaining VM to a safepoint and stop
873 // the compiler threads at safepoint
874 // <-- do not use anything that could get blocked by Safepoint -->
875 // + Disable tracing at JNI/JVM barriers
876 // + Set _vm_exited flag for threads that are still running native code
877 // + Call exit_globals()
878 // > deletes tty
879 // > deletes PerfMemory resources
880 // + Delete this thread
881 // + Return to caller
882
883 void Threads::destroy_vm() {
884 JavaThread* thread = JavaThread::current();
885
886 #ifdef ASSERT
887 _vm_complete = false;
888 #endif
889 // Wait until we are the last non-daemon thread to execute, or
890 // if we are a daemon then wait until the last non-daemon thread has
891 // executed.
892 bool daemon = java_lang_Thread::is_daemon(thread->threadObj());
893 int expected = daemon ? 0 : 1;
894 {
895 MonitorLocker nu(Threads_lock);
896 while (Threads::number_of_non_daemon_threads() > expected)
897 // This wait should make safepoint checks, wait without a timeout.
898 nu.wait(0);
899 }
900
901 EventShutdown e;
902 if (e.should_commit()) {
903 e.set_reason("No remaining non-daemon Java threads");
904 e.commit();
905 }
906
907 // Hang forever on exit if we are reporting an error.
908 if (ShowMessageBoxOnError && VMError::is_error_reported()) {
909 os::infinite_sleep();
910 }
911 os::wait_for_keypress_at_exit();
912
913 // run Java level shutdown hooks
914 thread->invoke_shutdown_hooks();
915
916 before_exit(thread);
917
918 thread->exit(true);
919
920 // We are no longer on the main thread list but could still be in a
921 // secondary list where another thread may try to interact with us.
922 // So wait until all such interactions are complete before we bring
923 // the VM to the termination safepoint. Normally this would be done
924 // using thread->smr_delete() below where we delete the thread, but
925 // we can't call that after the termination safepoint is active as
926 // we will deadlock on the Threads_lock. Once all interactions are
927 // complete it is safe to directly delete the thread at any time.
928 ThreadsSMRSupport::wait_until_not_protected(thread);
929
930 // Stop VM thread.
931 {
932 // 4945125 The vm thread comes to a safepoint during exit.
933 // GC vm_operations can get caught at the safepoint, and the
934 // heap is unparseable if they are caught. Grab the Heap_lock
935 // to prevent this. The GC vm_operations will not be able to
936 // queue until after the vm thread is dead. After this point,
937 // we'll never emerge out of the safepoint before the VM exits.
938 // Assert that the thread is terminated so that acquiring the
939 // Heap_lock doesn't cause the terminated thread to participate in
940 // the safepoint protocol.
941
942 assert(thread->is_terminated(), "must be terminated here");
943 MutexLocker ml(Heap_lock);
944
945 VMThread::wait_for_vm_thread_exit();
946 assert(SafepointSynchronize::is_at_safepoint(), "VM thread should exit at Safepoint");
947 VMThread::destroy();
948 }
949
950 // Now, all Java threads are gone except daemon threads. Daemon threads
951 // running Java code or in VM are stopped by the Safepoint. However,
952 // daemon threads executing native code are still running. But they
953 // will be stopped at native=>Java/VM barriers. Note that we can't
954 // simply kill or suspend them, as it is inherently deadlock-prone.
955
956 VM_Exit::set_vm_exited();
957
958 // Clean up ideal graph printers after the VMThread has started
959 // the final safepoint which will block all the Compiler threads.
960 // Note that this Thread has already logically exited so the
961 // clean_up() function's use of a JavaThreadIteratorWithHandle
962 // would be a problem except set_vm_exited() has remembered the
963 // shutdown thread which is granted a policy exception.
964 #if defined(COMPILER2) && !defined(PRODUCT)
965 IdealGraphPrinter::clean_up();
966 #endif
967
968 notify_vm_shutdown();
969
970 // exit_globals() will delete tty
971 exit_globals();
972
973 // Deleting the shutdown thread here is safe. See comment on
974 // wait_until_not_protected() above.
975 delete thread;
976
977 #if INCLUDE_JVMCI
978 if (JVMCICounterSize > 0) {
979 FREE_C_HEAP_ARRAY(jlong, JavaThread::_jvmci_old_thread_counters);
980 }
981 #endif
982
983 LogConfiguration::finalize();
984 }
985
986
987 jboolean Threads::is_supported_jni_version_including_1_1(jint version) {
988 if (version == JNI_VERSION_1_1) return JNI_TRUE;
989 return is_supported_jni_version(version);
990 }
991
992
993 jboolean Threads::is_supported_jni_version(jint version) {
994 if (version == JNI_VERSION_1_2) return JNI_TRUE;
995 if (version == JNI_VERSION_1_4) return JNI_TRUE;
996 if (version == JNI_VERSION_1_6) return JNI_TRUE;
997 if (version == JNI_VERSION_1_8) return JNI_TRUE;
998 if (version == JNI_VERSION_9) return JNI_TRUE;
999 if (version == JNI_VERSION_10) return JNI_TRUE;
1000 if (version == JNI_VERSION_19) return JNI_TRUE;
1001 if (version == JNI_VERSION_20) return JNI_TRUE;
1002 if (version == JNI_VERSION_21) return JNI_TRUE;
1003 if (version == JNI_VERSION_24) return JNI_TRUE;
1004 return JNI_FALSE;
1005 }
1006
1007 void Threads::add(JavaThread* p, bool force_daemon) {
1008 // The threads lock must be owned at this point
1009 assert(Threads_lock->owned_by_self(), "must have threads lock");
1010
1011 BarrierSet::barrier_set()->on_thread_attach(p);
1012
1013 // Once a JavaThread is added to the Threads list, smr_delete() has
1014 // to be used to delete it. Otherwise we can just delete it directly.
1015 p->set_on_thread_list();
1016
1017 _number_of_threads++;
1018 oop threadObj = p->threadObj();
1019 bool daemon = true;
1020 // Bootstrapping problem: threadObj can be null for initial
1021 // JavaThread (or for threads attached via JNI)
1022 if (!force_daemon &&
1023 (threadObj == nullptr || !java_lang_Thread::is_daemon(threadObj))) {
1024 _number_of_non_daemon_threads++;
1025 daemon = false;
1026 }
1027
1028 ThreadService::add_thread(p, daemon);
1029
1030 // Maintain fast thread list
1031 ThreadsSMRSupport::add_thread(p);
1032
1033 // Increase the ObjectMonitor ceiling for the new thread.
1034 ObjectSynchronizer::inc_in_use_list_ceiling();
1035
1036 // Possible GC point.
1037 Events::log(Thread::current(), "Thread added: " INTPTR_FORMAT, p2i(p));
1038
1039 // Make new thread known to active EscapeBarrier
1040 EscapeBarrier::thread_added(p);
1041 }
1042
1043 void Threads::remove(JavaThread* p, bool is_daemon) {
1044 // Extra scope needed for Thread_lock, so we can check
1045 // that we do not remove thread without safepoint code notice
1046 {
1047 ConditionalMutexLocker throttle_ml(ThreadsLockThrottle_lock, UseThreadsLockThrottleLock);
1048 MonitorLocker ml(Threads_lock);
1049
1050 if (ThreadIdTable::is_initialized()) {
1051 // This cleanup must be done before the current thread's GC barrier
1052 // is detached since we need to touch the threadObj oop.
1053 jlong tid = SharedRuntime::get_java_tid(p);
1054 ThreadIdTable::remove_thread(tid);
1055 }
1056
1057 // BarrierSet state must be destroyed after the last thread transition
1058 // before the thread terminates. Thread transitions result in calls to
1059 // StackWatermarkSet::on_safepoint(), which performs GC processing,
1060 // requiring the GC state to be alive.
1061 BarrierSet::barrier_set()->on_thread_detach(p);
1062 if (p->is_exiting()) {
1063 // If we got here via JavaThread::exit(), then we remember that the
1064 // thread's GC barrier has been detached. We don't do this when we get
1065 // here from another path, e.g., cleanup_failed_attach_current_thread().
1066 p->set_terminated(JavaThread::_thread_gc_barrier_detached);
1067 }
1068
1069 assert(ThreadsSMRSupport::get_java_thread_list()->includes(p), "p must be present");
1070
1071 // Maintain fast thread list
1072 ThreadsSMRSupport::remove_thread(p);
1073
1074 _number_of_threads--;
1075 if (!is_daemon) {
1076 _number_of_non_daemon_threads--;
1077
1078 // If this is the last non-daemon thread then we need to do
1079 // a notify on the Threads_lock so a thread waiting
1080 // on destroy_vm will wake up. But that thread could be a daemon
1081 // or non-daemon, so we notify for both the 0 and 1 case.
1082 if (number_of_non_daemon_threads() <= 1) {
1083 ml.notify_all();
1084 }
1085 }
1086 ThreadService::remove_thread(p, is_daemon);
1087
1088 // Make sure that safepoint code disregard this thread. This is needed since
1089 // the thread might mess around with locks after this point. This can cause it
1090 // to do callbacks into the safepoint code. However, the safepoint code is not aware
1091 // of this thread since it is removed from the queue.
1092 p->set_terminated(JavaThread::_thread_terminated);
1093
1094 // Notify threads waiting in EscapeBarriers
1095 EscapeBarrier::thread_removed(p);
1096 } // unlock Threads_lock and ThreadsLockThrottle_lock
1097
1098 // Reduce the ObjectMonitor ceiling for the exiting thread.
1099 ObjectSynchronizer::dec_in_use_list_ceiling();
1100
1101 // Since Events::log uses a lock, we grab it outside the Threads_lock
1102 Events::log(Thread::current(), "Thread exited: " INTPTR_FORMAT, p2i(p));
1103 }
1104
1105 // Operations on the Threads list for GC. These are not explicitly locked,
1106 // but the garbage collector must provide a safe context for them to run.
1107 // In particular, these things should never be called when the Threads_lock
1108 // is held by some other thread. (Note: the Safepoint abstraction also
1109 // uses the Threads_lock to guarantee this property. It also makes sure that
1110 // all threads gets blocked when exiting or starting).
1111
1112 void Threads::oops_do(OopClosure* f, NMethodClosure* cf) {
1113 ALL_JAVA_THREADS(p) {
1114 p->oops_do(f, cf);
1115 }
1116 VMThread::vm_thread()->oops_do(f, cf);
1117 }
1118
1119 void Threads::change_thread_claim_token() {
1120 if (++_thread_claim_token == 0) {
1121 // On overflow of the token counter, there is a risk of future
1122 // collisions between a new global token value and a stale token
1123 // for a thread, because not all iterations visit all threads.
1124 // (Though it's pretty much a theoretical concern for non-trivial
1125 // token counter sizes.) To deal with the possibility, reset all
1126 // the thread tokens to zero on global token overflow.
1127 struct ResetClaims : public ThreadClosure {
1128 virtual void do_thread(Thread* t) {
1129 t->claim_threads_do(false, 0);
1130 }
1131 } reset_claims;
1132 Threads::threads_do(&reset_claims);
1133 // On overflow, update the global token to non-zero, to
1134 // avoid the special "never claimed" initial thread value.
1135 _thread_claim_token = 1;
1136 }
1137 }
1138
1139 #ifdef ASSERT
1140 static void assert_thread_claimed(const char* kind, Thread* t, uintx expected) {
1141 const uintx token = t->threads_do_token();
1142 assert(token == expected,
1143 "%s " PTR_FORMAT " has incorrect value " UINTX_FORMAT " != "
1144 UINTX_FORMAT, kind, p2i(t), token, expected);
1145 }
1146
1147 void Threads::assert_all_threads_claimed() {
1148 ALL_JAVA_THREADS(p) {
1149 assert_thread_claimed("JavaThread", p, _thread_claim_token);
1150 }
1151
1152 struct NJTClaimedVerifierClosure : public ThreadClosure {
1153 uintx _thread_claim_token;
1154
1155 NJTClaimedVerifierClosure(uintx thread_claim_token) : ThreadClosure(), _thread_claim_token(thread_claim_token) { }
1156
1157 virtual void do_thread(Thread* thread) override {
1158 assert_thread_claimed("Non-JavaThread", VMThread::vm_thread(), _thread_claim_token);
1159 }
1160 } tc(_thread_claim_token);
1161
1162 non_java_threads_do(&tc);
1163 }
1164 #endif // ASSERT
1165
1166 class ParallelOopsDoThreadClosure : public ThreadClosure {
1167 private:
1168 OopClosure* _f;
1169 NMethodClosure* _cf;
1170 public:
1171 ParallelOopsDoThreadClosure(OopClosure* f, NMethodClosure* cf) : _f(f), _cf(cf) {}
1172 void do_thread(Thread* t) {
1173 t->oops_do(_f, _cf);
1174 }
1175 };
1176
1177 void Threads::possibly_parallel_oops_do(bool is_par, OopClosure* f, NMethodClosure* cf) {
1178 ParallelOopsDoThreadClosure tc(f, cf);
1179 possibly_parallel_threads_do(is_par, &tc);
1180 }
1181
1182 void Threads::metadata_do(MetadataClosure* f) {
1183 ALL_JAVA_THREADS(p) {
1184 p->metadata_do(f);
1185 }
1186 }
1187
1188 class ThreadHandlesClosure : public ThreadClosure {
1189 void (*_f)(Metadata*);
1190 public:
1191 ThreadHandlesClosure(void f(Metadata*)) : _f(f) {}
1192 virtual void do_thread(Thread* thread) {
1193 thread->metadata_handles_do(_f);
1194 }
1195 };
1196
1197 void Threads::metadata_handles_do(void f(Metadata*)) {
1198 // Only walk the Handles in Thread.
1199 ThreadHandlesClosure handles_closure(f);
1200 threads_do(&handles_closure);
1201 }
1202
1203 #if INCLUDE_JVMTI
1204 // Get Java threads that are waiting to enter or re-enter the specified monitor.
1205 // Java threads that are executing mounted virtual threads are not included.
1206 GrowableArray<JavaThread*>* Threads::get_pending_threads(ThreadsList * t_list,
1207 int count,
1208 address monitor) {
1209 assert(Thread::current()->is_VM_thread(), "Must be the VM thread");
1210 GrowableArray<JavaThread*>* result = new GrowableArray<JavaThread*>(count);
1211
1212 int i = 0;
1213 for (JavaThread* p : *t_list) {
1214 if (!p->can_call_java()) continue;
1215
1216 oop thread_oop = JvmtiEnvBase::get_vthread_or_thread_oop(p);
1217 if (thread_oop->is_a(vmClasses::BaseVirtualThread_klass())) {
1218 continue;
1219 }
1220 // The first stage of async deflation does not affect any field
1221 // used by this comparison so the ObjectMonitor* is usable here.
1222 address pending = (address)p->current_pending_monitor();
1223 address waiting = (address)p->current_waiting_monitor();
1224 // do not include virtual threads to the list
1225 jint state = JvmtiEnvBase::get_thread_state(thread_oop, p);
1226 if (pending == monitor || (waiting == monitor &&
1227 (state & JVMTI_THREAD_STATE_BLOCKED_ON_MONITOR_ENTER))
1228 ) { // found a match
1229 if (i < count) result->append(p); // save the first count matches
1230 i++;
1231 }
1232 }
1233
1234 return result;
1235 }
1236 #endif // INCLUDE_JVMTI
1237
1238 JavaThread *Threads::owning_thread_from_stacklock(ThreadsList * t_list, address basicLock) {
1239 assert(LockingMode == LM_LEGACY, "Not with new lightweight locking");
1240
1241 JavaThread* the_owner = nullptr;
1242 for (JavaThread* q : *t_list) {
1243 if (q->is_lock_owned(basicLock)) {
1244 the_owner = q;
1245 break;
1246 }
1247 }
1248 return the_owner;
1249 }
1250
1251 JavaThread* Threads::owning_thread_from_object(ThreadsList * t_list, oop obj) {
1252 assert(LockingMode == LM_LIGHTWEIGHT, "Only with new lightweight locking");
1253 for (JavaThread* q : *t_list) {
1254 // Need to start processing before accessing oops in the thread.
1255 StackWatermark* watermark = StackWatermarkSet::get(q, StackWatermarkKind::gc);
1256 if (watermark != nullptr) {
1257 watermark->start_processing();
1258 }
1259
1260 if (q->lock_stack().contains(obj)) {
1261 return q;
1262 }
1263 }
1264 return nullptr;
1265 }
1266
1267 JavaThread* Threads::owning_thread_from_monitor(ThreadsList* t_list, ObjectMonitor* monitor) {
1268 if (monitor->is_owner_anonymous()) {
1269 if (LockingMode == LM_LIGHTWEIGHT) {
1270 return owning_thread_from_object(t_list, monitor->object());
1271 } else {
1272 assert(LockingMode == LM_LEGACY, "invariant");
1273 return owning_thread_from_stacklock(t_list, (address)monitor->stack_locker());
1274 }
1275 } else {
1276 JavaThread* the_owner = nullptr;
1277 for (JavaThread* q : *t_list) {
1278 if (monitor->is_owner(q)) {
1279 the_owner = q;
1280 break;
1281 }
1282 }
1283 return the_owner;
1284 }
1285 }
1286
1287 class PrintOnClosure : public ThreadClosure {
1288 private:
1289 outputStream* _st;
1290
1291 public:
1292 PrintOnClosure(outputStream* st) :
1293 _st(st) {}
1294
1295 virtual void do_thread(Thread* thread) {
1296 if (thread != nullptr) {
1297 thread->print_on(_st);
1298 _st->cr();
1299 }
1300 }
1301 };
1302
1303 // Threads::print_on() is called at safepoint by VM_PrintThreads operation.
1304 void Threads::print_on(outputStream* st, bool print_stacks,
1305 bool internal_format, bool print_concurrent_locks,
1306 bool print_extended_info) {
1307 char buf[32];
1308 st->print_raw_cr(os::local_time_string(buf, sizeof(buf)));
1309
1310 st->print_cr("Full thread dump %s (%s %s):",
1311 VM_Version::vm_name(),
1312 VM_Version::vm_release(),
1313 VM_Version::vm_info_string());
1314 st->cr();
1315
1316 #if INCLUDE_SERVICES
1317 // Dump concurrent locks
1318 ConcurrentLocksDump concurrent_locks;
1319 if (print_concurrent_locks) {
1320 concurrent_locks.dump_at_safepoint();
1321 }
1322 #endif // INCLUDE_SERVICES
1323
1324 ThreadsSMRSupport::print_info_on(st);
1325 st->cr();
1326
1327 ALL_JAVA_THREADS(p) {
1328 ResourceMark rm;
1329 p->print_on(st, print_extended_info);
1330 if (print_stacks) {
1331 if (internal_format) {
1332 p->trace_stack();
1333 } else {
1334 p->print_stack_on(st);
1335 if (p->is_vthread_mounted()) {
1336 // _lock_id is the thread ID of the mounted virtual thread
1337 st->print_cr(" Mounted virtual thread #" INT64_FORMAT, p->lock_id());
1338 p->print_vthread_stack_on(st);
1339 }
1340 }
1341 }
1342 st->cr();
1343 #if INCLUDE_SERVICES
1344 if (print_concurrent_locks) {
1345 concurrent_locks.print_locks_on(p, st);
1346 }
1347 #endif // INCLUDE_SERVICES
1348 }
1349
1350 PrintOnClosure cl(st);
1351 non_java_threads_do(&cl);
1352
1353 st->flush();
1354 }
1355
1356 void Threads::print_on_error(Thread* this_thread, outputStream* st, Thread* current, char* buf,
1357 int buflen, bool* found_current) {
1358 if (this_thread != nullptr) {
1359 bool is_current = (current == this_thread);
1360 *found_current = *found_current || is_current;
1361 st->print("%s", is_current ? "=>" : " ");
1362
1363 st->print(PTR_FORMAT, p2i(this_thread));
1364 st->print(" ");
1365 this_thread->print_on_error(st, buf, buflen);
1366 st->cr();
1367 }
1368 }
1369
1370 class PrintOnErrorClosure : public ThreadClosure {
1371 outputStream* _st;
1372 Thread* _current;
1373 char* _buf;
1374 int _buflen;
1375 bool* _found_current;
1376 unsigned _num_printed;
1377 public:
1378 PrintOnErrorClosure(outputStream* st, Thread* current, char* buf,
1379 int buflen, bool* found_current) :
1380 _st(st), _current(current), _buf(buf), _buflen(buflen), _found_current(found_current),
1381 _num_printed(0) {}
1382
1383 virtual void do_thread(Thread* thread) {
1384 _num_printed++;
1385 Threads::print_on_error(thread, _st, _current, _buf, _buflen, _found_current);
1386 }
1387
1388 unsigned num_printed() const { return _num_printed; }
1389 };
1390
1391 // Threads::print_on_error() is called by fatal error handler. It's possible
1392 // that VM is not at safepoint and/or current thread is inside signal handler.
1393 // Don't print stack trace, as the stack may not be walkable. Don't allocate
1394 // memory (even in resource area), it might deadlock the error handler.
1395 void Threads::print_on_error(outputStream* st, Thread* current, char* buf,
1396 int buflen) {
1397 ThreadsSMRSupport::print_info_on(st);
1398 st->cr();
1399
1400 bool found_current = false;
1401 st->print_cr("Java Threads: ( => current thread )");
1402 unsigned num_java = 0;
1403 ALL_JAVA_THREADS(thread) {
1404 print_on_error(thread, st, current, buf, buflen, &found_current);
1405 num_java++;
1406 }
1407 st->print_cr("Total: %u", num_java);
1408 st->cr();
1409
1410 st->print_cr("Other Threads:");
1411 unsigned num_other = ((VMThread::vm_thread() != nullptr) ? 1 : 0) +
1412 ((WatcherThread::watcher_thread() != nullptr) ? 1 : 0) +
1413 ((AsyncLogWriter::instance() != nullptr) ? 1 : 0);
1414 print_on_error(VMThread::vm_thread(), st, current, buf, buflen, &found_current);
1415 print_on_error(WatcherThread::watcher_thread(), st, current, buf, buflen, &found_current);
1416 print_on_error(AsyncLogWriter::instance(), st, current, buf, buflen, &found_current);
1417
1418 if (Universe::heap() != nullptr) {
1419 PrintOnErrorClosure print_closure(st, current, buf, buflen, &found_current);
1420 Universe::heap()->gc_threads_do(&print_closure);
1421 num_other += print_closure.num_printed();
1422 }
1423
1424 if (!found_current) {
1425 st->cr();
1426 st->print("=>" PTR_FORMAT " (exited) ", p2i(current));
1427 current->print_on_error(st, buf, buflen);
1428 num_other++;
1429 st->cr();
1430 }
1431 st->print_cr("Total: %u", num_other);
1432 st->cr();
1433
1434 st->print_cr("Threads with active compile tasks:");
1435 unsigned num = print_threads_compiling(st, buf, buflen);
1436 st->print_cr("Total: %u", num);
1437 }
1438
1439 unsigned Threads::print_threads_compiling(outputStream* st, char* buf, int buflen, bool short_form) {
1440 unsigned num = 0;
1441 ALL_JAVA_THREADS(thread) {
1442 if (thread->is_Compiler_thread()) {
1443 CompilerThread* ct = (CompilerThread*) thread;
1444
1445 // Keep task in local variable for null check.
1446 // ct->_task might be set to null by concurring compiler thread
1447 // because it completed the compilation. The task is never freed,
1448 // though, just returned to a free list.
1449 CompileTask* task = ct->task();
1450 if (task != nullptr) {
1451 thread->print_name_on_error(st, buf, buflen);
1452 st->print(" ");
1453 task->print(st, nullptr, short_form, true);
1454 num++;
1455 }
1456 }
1457 }
1458 return num;
1459 }
1460
1461 void Threads::verify() {
1462 ALL_JAVA_THREADS(p) {
1463 p->verify();
1464 }
1465 VMThread* thread = VMThread::vm_thread();
1466 if (thread != nullptr) thread->verify();
1467 }