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 // Set thread status to running since main thread has
170 // been started and running.
171 java_lang_Thread::set_thread_status(thread_oop(),
172 JavaThreadStatus::RUNNABLE);
173 }
174
175 // Extract version and vendor specific information from
176 // java.lang.VersionProps fields.
177 // Returned char* is allocated in the thread's resource area
178 // so must be copied for permanency.
179 static const char* get_java_version_info(InstanceKlass* ik,
180 Symbol* field_name) {
181 fieldDescriptor fd;
182 bool found = ik != nullptr &&
183 ik->find_local_field(field_name,
184 vmSymbols::string_signature(), &fd);
185 if (found) {
186 oop name_oop = ik->java_mirror()->obj_field(fd.offset());
187 if (name_oop == nullptr) {
188 return nullptr;
189 }
190 const char* name = java_lang_String::as_utf8_string(name_oop);
191 return name;
192 } else {
193 return nullptr;
194 }
195 }
196
197 // ======= Threads ========
198
199 // The Threads class links together all active threads, and provides
200 // operations over all threads. It is protected by the Threads_lock,
201 // which is also used in other global contexts like safepointing.
202 // ThreadsListHandles are used to safely perform operations on one
203 // or more threads without the risk of the thread exiting during the
204 // operation.
205 //
206 // Note: The Threads_lock is currently more widely used than we
207 // would like. We are actively migrating Threads_lock uses to other
208 // mechanisms in order to reduce Threads_lock contention.
209
210 int Threads::_number_of_threads = 0;
211 int Threads::_number_of_non_daemon_threads = 0;
212 int Threads::_return_code = 0;
213 uintx Threads::_thread_claim_token = 1; // Never zero.
214
215 #ifdef ASSERT
216 bool Threads::_vm_complete = false;
217 #endif
218
219 // General purpose hook into Java code, run once when the VM is initialized.
220 // The Java library method itself may be changed independently from the VM.
221 static void call_postVMInitHook(TRAPS) {
222 Klass* klass = SystemDictionary::resolve_or_null(vmSymbols::jdk_internal_vm_PostVMInitHook(), THREAD);
223 if (klass != nullptr) {
224 JavaValue result(T_VOID);
225 JavaCalls::call_static(&result, klass, vmSymbols::run_method_name(),
226 vmSymbols::void_method_signature(),
227 CHECK);
228 }
229 }
230
231 // All NonJavaThreads (i.e., every non-JavaThread in the system).
232 void Threads::non_java_threads_do(ThreadClosure* tc) {
233 NoSafepointVerifier nsv;
234 for (NonJavaThread::Iterator njti; !njti.end(); njti.step()) {
235 tc->do_thread(njti.current());
236 }
237 }
238
239 // All JavaThreads
240 #define ALL_JAVA_THREADS(X) \
241 for (JavaThread* X : *ThreadsSMRSupport::get_java_thread_list())
242
243 // All JavaThreads
244 void Threads::java_threads_do(ThreadClosure* tc) {
245 assert_locked_or_safepoint(Threads_lock);
246 // ALL_JAVA_THREADS iterates through all JavaThreads.
247 ALL_JAVA_THREADS(p) {
248 tc->do_thread(p);
249 }
250 }
251
252 // All JavaThreads + all non-JavaThreads (i.e., every thread in the system).
253 void Threads::threads_do(ThreadClosure* tc) {
254 assert_locked_or_safepoint(Threads_lock);
255 java_threads_do(tc);
256 non_java_threads_do(tc);
257 }
258
259 void Threads::possibly_parallel_threads_do(bool is_par, ThreadClosure* tc) {
260 assert_at_safepoint();
261
262 uintx claim_token = Threads::thread_claim_token();
263 ALL_JAVA_THREADS(p) {
264 if (p->claim_threads_do(is_par, claim_token)) {
265 tc->do_thread(p);
266 }
267 }
268 for (NonJavaThread::Iterator njti; !njti.end(); njti.step()) {
269 Thread* current = njti.current();
270 if (current->claim_threads_do(is_par, claim_token)) {
271 tc->do_thread(current);
272 }
273 }
274 }
275
276 // The system initialization in the library has three phases.
277 //
278 // Phase 1: java.lang.System class initialization
279 // java.lang.System is a primordial class loaded and initialized
280 // by the VM early during startup. java.lang.System.<clinit>
281 // only does registerNatives and keeps the rest of the class
282 // initialization work later until thread initialization completes.
283 //
284 // System.initPhase1 initializes the system properties, the static
285 // fields in, out, and err. Set up java signal handlers, OS-specific
286 // system settings, and thread group of the main thread.
287 static void call_initPhase1(TRAPS) {
288 Klass* klass = vmClasses::System_klass();
289 JavaValue result(T_VOID);
290 JavaCalls::call_static(&result, klass, vmSymbols::initPhase1_name(),
291 vmSymbols::void_method_signature(), CHECK);
292 }
293
294 // Phase 2. Module system initialization
295 // This will initialize the module system. Only java.base classes
296 // can be loaded until phase 2 completes.
297 //
298 // Call System.initPhase2 after the compiler initialization and jsr292
299 // classes get initialized because module initialization runs a lot of java
300 // code, that for performance reasons, should be compiled. Also, this will
301 // enable the startup code to use lambda and other language features in this
302 // phase and onward.
303 //
304 // After phase 2, The VM will begin search classes from -Xbootclasspath/a.
305 static void call_initPhase2(TRAPS) {
306 TraceTime timer("Initialize module system", TRACETIME_LOG(Info, startuptime));
307
308 Klass* klass = vmClasses::System_klass();
309
310 JavaValue result(T_INT);
311 JavaCallArguments args;
312 args.push_int(DisplayVMOutputToStderr);
313 args.push_int(log_is_enabled(Debug, init)); // print stack trace if exception thrown
314 JavaCalls::call_static(&result, klass, vmSymbols::initPhase2_name(),
315 vmSymbols::boolean_boolean_int_signature(), &args, CHECK);
316 if (result.get_jint() != JNI_OK) {
317 vm_exit_during_initialization(); // no message or exception
318 }
319
320 universe_post_module_init();
321 }
322
323 // Phase 3. final setup - set security manager, system class loader and TCCL
324 //
325 // This will instantiate and set the security manager, set the system class
326 // loader as well as the thread context class loader. The security manager
327 // and system class loader may be a custom class loaded from -Xbootclasspath/a,
328 // other modules or the application's classpath.
329 static void call_initPhase3(TRAPS) {
330 Klass* klass = vmClasses::System_klass();
331 JavaValue result(T_VOID);
332 JavaCalls::call_static(&result, klass, vmSymbols::initPhase3_name(),
333 vmSymbols::void_method_signature(), CHECK);
334 }
335
336 void Threads::initialize_java_lang_classes(JavaThread* main_thread, TRAPS) {
337 TraceTime timer("Initialize java.lang classes", TRACETIME_LOG(Info, startuptime));
338
339 initialize_class(vmSymbols::java_lang_String(), CHECK);
340
341 // Inject CompactStrings value after the static initializers for String ran.
342 java_lang_String::set_compact_strings(CompactStrings);
343
344 // Initialize java_lang.System (needed before creating the thread)
345 initialize_class(vmSymbols::java_lang_System(), CHECK);
346 // The VM creates & returns objects of this class. Make sure it's initialized.
347 initialize_class(vmSymbols::java_lang_Class(), CHECK);
348 initialize_class(vmSymbols::java_lang_ThreadGroup(), CHECK);
349 Handle thread_group = create_initial_thread_group(CHECK);
350 Universe::set_main_thread_group(thread_group());
351 initialize_class(vmSymbols::java_lang_Thread(), CHECK);
352 create_initial_thread(thread_group, main_thread, CHECK);
353
354 // The VM creates objects of this class.
355 initialize_class(vmSymbols::java_lang_Module(), CHECK);
356
357 #ifdef ASSERT
358 InstanceKlass *k = vmClasses::UnsafeConstants_klass();
359 assert(k->is_not_initialized(), "UnsafeConstants should not already be initialized");
360 #endif
361
362 // initialize the hardware-specific constants needed by Unsafe
363 initialize_class(vmSymbols::jdk_internal_misc_UnsafeConstants(), CHECK);
364 jdk_internal_misc_UnsafeConstants::set_unsafe_constants();
365
366 // The VM preresolves methods to these classes. Make sure that they get initialized
367 initialize_class(vmSymbols::java_lang_reflect_Method(), CHECK);
368 initialize_class(vmSymbols::java_lang_ref_Finalizer(), CHECK);
369
370 // Phase 1 of the system initialization in the library, java.lang.System class initialization
371 call_initPhase1(CHECK);
372
373 // Get the Java runtime name, version, and vendor info after java.lang.System is initialized.
374 // Some values are actually configure-time constants but some can be set via the jlink tool and
375 // so must be read dynamically. We treat them all the same.
376 InstanceKlass* ik = SystemDictionary::find_instance_klass(THREAD, vmSymbols::java_lang_VersionProps(),
377 Handle(), Handle());
378 {
379 ResourceMark rm(main_thread);
380 JDK_Version::set_java_version(get_java_version_info(ik, vmSymbols::java_version_name()));
381
382 JDK_Version::set_runtime_name(get_java_version_info(ik, vmSymbols::java_runtime_name_name()));
383
384 JDK_Version::set_runtime_version(get_java_version_info(ik, vmSymbols::java_runtime_version_name()));
385
386 JDK_Version::set_runtime_vendor_version(get_java_version_info(ik, vmSymbols::java_runtime_vendor_version_name()));
387
388 JDK_Version::set_runtime_vendor_vm_bug_url(get_java_version_info(ik, vmSymbols::java_runtime_vendor_vm_bug_url_name()));
389 }
390
391 // an instance of OutOfMemory exception has been allocated earlier
392 initialize_class(vmSymbols::java_lang_OutOfMemoryError(), CHECK);
393 initialize_class(vmSymbols::java_lang_NullPointerException(), CHECK);
394 initialize_class(vmSymbols::java_lang_ClassCastException(), CHECK);
395 initialize_class(vmSymbols::java_lang_ArrayStoreException(), CHECK);
396 initialize_class(vmSymbols::java_lang_ArithmeticException(), CHECK);
397 initialize_class(vmSymbols::java_lang_ArrayIndexOutOfBoundsException(), CHECK);
398 initialize_class(vmSymbols::java_lang_StackOverflowError(), CHECK);
399 initialize_class(vmSymbols::java_lang_IllegalMonitorStateException(), CHECK);
400 initialize_class(vmSymbols::java_lang_IllegalArgumentException(), CHECK);
401 }
402
403 void Threads::initialize_jsr292_core_classes(TRAPS) {
404 TraceTime timer("Initialize java.lang.invoke classes", TRACETIME_LOG(Info, startuptime));
405
406 initialize_class(vmSymbols::java_lang_invoke_MethodHandle(), CHECK);
407 initialize_class(vmSymbols::java_lang_invoke_ResolvedMethodName(), CHECK);
408 initialize_class(vmSymbols::java_lang_invoke_MemberName(), CHECK);
409 initialize_class(vmSymbols::java_lang_invoke_MethodHandleNatives(), CHECK);
410 }
411
412 jint Threads::create_vm(JavaVMInitArgs* args, bool* canTryAgain) {
413 extern void JDK_Version_init();
414
415 // Preinitialize version info.
416 VM_Version::early_initialize();
417
418 // Check version
419 if (!is_supported_jni_version(args->version)) return JNI_EVERSION;
420
421 // Initialize library-based TLS
422 ThreadLocalStorage::init();
423
424 // Initialize the output stream module
425 ostream_init();
426
427 // Process java launcher properties.
428 Arguments::process_sun_java_launcher_properties(args);
429
430 // Initialize the os module
431 os::init();
432
433 MACOS_AARCH64_ONLY(os::current_thread_enable_wx(WXWrite));
434
435 // Record VM creation timing statistics
436 TraceVmCreationTime create_vm_timer;
437 create_vm_timer.start();
438
439 // Initialize system properties.
440 Arguments::init_system_properties();
441
442 // So that JDK version can be used as a discriminator when parsing arguments
443 JDK_Version_init();
444
445 // Update/Initialize System properties after JDK version number is known
446 Arguments::init_version_specific_system_properties();
447
448 // Make sure to initialize log configuration *before* parsing arguments
449 LogConfiguration::initialize(create_vm_timer.begin_time());
450
451 // Parse arguments
452 // Note: this internally calls os::init_container_support()
453 jint parse_result = Arguments::parse(args);
454 if (parse_result != JNI_OK) return parse_result;
455
456 // Initialize NMT right after argument parsing to keep the pre-NMT-init window small.
457 MemTracker::initialize();
458
459 os::init_before_ergo();
460
461 jint ergo_result = Arguments::apply_ergo();
462 if (ergo_result != JNI_OK) return ergo_result;
463
464 // Final check of all ranges after ergonomics which may change values.
465 if (!JVMFlagLimit::check_all_ranges()) {
466 return JNI_EINVAL;
467 }
468
469 // Final check of all 'AfterErgo' constraints after ergonomics which may change values.
470 bool constraint_result = JVMFlagLimit::check_all_constraints(JVMFlagConstraintPhase::AfterErgo);
471 if (!constraint_result) {
472 return JNI_EINVAL;
473 }
474
475 if (PauseAtStartup) {
476 os::pause();
477 }
478
479 HOTSPOT_VM_INIT_BEGIN();
480
481 // Timing (must come after argument parsing)
482 TraceTime timer("Create VM", TRACETIME_LOG(Info, startuptime));
483
484 // Initialize the os module after parsing the args
485 jint os_init_2_result = os::init_2();
486 if (os_init_2_result != JNI_OK) return os_init_2_result;
487
488 #ifdef CAN_SHOW_REGISTERS_ON_ASSERT
489 // Initialize assert poison page mechanism.
490 if (ShowRegistersOnAssert) {
491 initialize_assert_poison();
492 }
493 #endif // CAN_SHOW_REGISTERS_ON_ASSERT
494
495 SafepointMechanism::initialize();
496
497 jint adjust_after_os_result = Arguments::adjust_after_os();
498 if (adjust_after_os_result != JNI_OK) return adjust_after_os_result;
499
500 // Initialize output stream logging
501 ostream_init_log();
502
503 // Launch -agentlib/-agentpath and converted -Xrun agents
504 JvmtiAgentList::load_agents();
505
506 // Initialize Threads state
507 _number_of_threads = 0;
508 _number_of_non_daemon_threads = 0;
509
510 // Initialize global data structures and create system classes in heap
511 vm_init_globals();
512
513 #if INCLUDE_JVMCI
514 if (JVMCICounterSize > 0) {
515 JavaThread::_jvmci_old_thread_counters = NEW_C_HEAP_ARRAY(jlong, JVMCICounterSize, mtJVMCI);
516 memset(JavaThread::_jvmci_old_thread_counters, 0, sizeof(jlong) * JVMCICounterSize);
517 } else {
518 JavaThread::_jvmci_old_thread_counters = nullptr;
519 }
520 #endif // INCLUDE_JVMCI
521
522 // Initialize OopStorage for threadObj
523 JavaThread::_thread_oop_storage = OopStorageSet::create_strong("Thread OopStorage", mtThread);
524
525 // Attach the main thread to this os thread
526 JavaThread* main_thread = new JavaThread();
527 main_thread->set_thread_state(_thread_in_vm);
528 main_thread->initialize_thread_current();
529 // must do this before set_active_handles
530 main_thread->record_stack_base_and_size();
531 main_thread->register_thread_stack_with_NMT();
532 main_thread->set_active_handles(JNIHandleBlock::allocate_block());
533 MACOS_AARCH64_ONLY(main_thread->init_wx());
534
535 if (!main_thread->set_as_starting_thread()) {
536 vm_shutdown_during_initialization(
537 "Failed necessary internal allocation. Out of swap space");
538 main_thread->smr_delete();
539 *canTryAgain = false; // don't let caller call JNI_CreateJavaVM again
540 return JNI_ENOMEM;
541 }
542
543 // Enable guard page *after* os::create_main_thread(), otherwise it would
544 // crash Linux VM, see notes in os_linux.cpp.
545 main_thread->stack_overflow_state()->create_stack_guard_pages();
546
547 // Initialize Java-Level synchronization subsystem
548 ObjectMonitor::Initialize();
549 ObjectSynchronizer::initialize();
550
551 // Initialize global modules
552 jint status = init_globals();
553 if (status != JNI_OK) {
554 main_thread->smr_delete();
555 *canTryAgain = false; // don't let caller call JNI_CreateJavaVM again
556 return status;
557 }
558
559 // Create WatcherThread as soon as we can since we need it in case
560 // of hangs during error reporting.
561 WatcherThread::start();
562
563 // Add main_thread to threads list to finish barrier setup with
564 // on_thread_attach. Should be before starting to build Java objects in
565 // init_globals2, which invokes barriers.
566 {
567 MutexLocker mu(Threads_lock);
568 Threads::add(main_thread);
569 }
570
571 status = init_globals2();
572 if (status != JNI_OK) {
573 Threads::remove(main_thread, false);
574 // It is possible that we managed to fully initialize Universe but have then
575 // failed by throwing an exception. In that case our caller JNI_CreateJavaVM
576 // will want to report it, so we can't delete the main thread.
577 if (!main_thread->has_pending_exception()) {
578 main_thread->smr_delete();
579 }
580 *canTryAgain = false; // don't let caller call JNI_CreateJavaVM again
581 return status;
582 }
583
584 JFR_ONLY(Jfr::on_create_vm_1();)
585
586 // Should be done after the heap is fully created
587 main_thread->cache_global_variables();
588
589 // Any JVMTI raw monitors entered in onload will transition into
590 // real raw monitor. VM is setup enough here for raw monitor enter.
591 JvmtiExport::transition_pending_onload_raw_monitors();
592
593 // Create the VMThread
594 { TraceTime timer("Start VMThread", TRACETIME_LOG(Info, startuptime));
595
596 VMThread::create();
597 VMThread* vmthread = VMThread::vm_thread();
598
599 if (!os::create_thread(vmthread, os::vm_thread)) {
600 vm_exit_during_initialization("Cannot create VM thread. "
601 "Out of system resources.");
602 }
603
604 // Wait for the VM thread to become ready, and VMThread::run to initialize
605 // Monitors can have spurious returns, must always check another state flag
606 {
607 MonitorLocker ml(Notify_lock);
608 os::start_thread(vmthread);
609 while (!vmthread->is_running()) {
610 ml.wait();
611 }
612 }
613 }
614
615 assert(Universe::is_fully_initialized(), "not initialized");
616 if (VerifyDuringStartup) {
617 // Make sure we're starting with a clean slate.
618 VM_Verify verify_op;
619 VMThread::execute(&verify_op);
620 }
621
622 // We need this to update the java.vm.info property in case any flags used
623 // to initially define it have been changed. This is needed for both CDS
624 // since UseSharedSpaces may be changed after java.vm.info
625 // is initially computed. See Abstract_VM_Version::vm_info_string().
626 // This update must happen before we initialize the java classes, but
627 // after any initialization logic that might modify the flags.
628 Arguments::update_vm_info_property(VM_Version::vm_info_string());
629
630 JavaThread* THREAD = JavaThread::current(); // For exception macros.
631 HandleMark hm(THREAD);
632
633 // Always call even when there are not JVMTI environments yet, since environments
634 // may be attached late and JVMTI must track phases of VM execution
635 JvmtiExport::enter_early_start_phase();
636
637 // Notify JVMTI agents that VM has started (JNI is up) - nop if no agents.
638 JvmtiExport::post_early_vm_start();
639
640 // Launch -Xrun agents early if EagerXrunInit is set
641 if (EagerXrunInit) {
642 JvmtiAgentList::load_xrun_agents();
643 }
644
645 initialize_java_lang_classes(main_thread, CHECK_JNI_ERR);
646
647 quicken_jni_functions();
648
649 // No more stub generation allowed after that point.
650 StubCodeDesc::freeze();
651
652 // Set flag that basic initialization has completed. Used by exceptions and various
653 // debug stuff, that does not work until all basic classes have been initialized.
654 set_init_completed();
655
656 LogConfiguration::post_initialize();
657 Metaspace::post_initialize();
658 MutexLockerImpl::post_initialize();
659
660 HOTSPOT_VM_INIT_END();
661
662 // record VM initialization completion time
663 #if INCLUDE_MANAGEMENT
664 Management::record_vm_init_completed();
665 #endif // INCLUDE_MANAGEMENT
666
667 log_info(os)("Initialized VM with process ID %d", os::current_process_id());
668
669 if (!FLAG_IS_DEFAULT(CreateCoredumpOnCrash) && CreateCoredumpOnCrash) {
670 char buffer[2*JVM_MAXPATHLEN];
671 os::check_core_dump_prerequisites(buffer, sizeof(buffer), true);
672 }
673
674 // Signal Dispatcher needs to be started before VMInit event is posted
675 os::initialize_jdk_signal_support(CHECK_JNI_ERR);
676
677 // Start Attach Listener if +StartAttachListener or it can't be started lazily
678 if (!DisableAttachMechanism) {
679 AttachListener::vm_start();
680 if (StartAttachListener || AttachListener::init_at_startup()) {
681 AttachListener::init();
682 }
683 }
684
685 // Launch -Xrun agents if EagerXrunInit is not set.
686 if (!EagerXrunInit) {
687 JvmtiAgentList::load_xrun_agents();
688 }
689
690 Arena::start_chunk_pool_cleaner_task();
691
692 // Start the service thread
693 // The service thread enqueues JVMTI deferred events and does various hashtable
694 // and other cleanups. Needs to start before the compilers start posting events.
695 ServiceThread::initialize();
696
697 // Start the monitor deflation thread:
698 MonitorDeflationThread::initialize();
699
700 // initialize compiler(s)
701 #if defined(COMPILER1) || COMPILER2_OR_JVMCI
702 bool init_compilation = true;
703 #if INCLUDE_JVMCI
704 bool force_JVMCI_initialization = false;
705 if (EnableJVMCI) {
706 // Initialize JVMCI eagerly when it is explicitly requested.
707 // Or when JVMCILibDumpJNIConfig or JVMCIPrintProperties is enabled.
708 force_JVMCI_initialization = EagerJVMCI || JVMCIPrintProperties || JVMCILibDumpJNIConfig;
709 if (!force_JVMCI_initialization && UseJVMCICompiler && !UseJVMCINativeLibrary && (!UseInterpreter || !BackgroundCompilation)) {
710 // Force initialization of jarjvmci otherwise requests for blocking
711 // compilations will not actually block until jarjvmci is initialized.
712 force_JVMCI_initialization = true;
713 }
714 if (JVMCIPrintProperties || JVMCILibDumpJNIConfig) {
715 // Both JVMCILibDumpJNIConfig and JVMCIPrintProperties exit the VM
716 // so compilation should be disabled. This prevents dumping or
717 // printing from happening more than once.
718 init_compilation = false;
719 }
720 }
721 #endif
722 if (init_compilation) {
723 CompileBroker::compilation_init(CHECK_JNI_ERR);
724 }
725 #endif
726
727 // Start string deduplication thread if requested.
728 if (StringDedup::is_enabled()) {
729 StringDedup::start();
730 }
731
732 // Pre-initialize some JSR292 core classes to avoid deadlock during class loading.
733 // It is done after compilers are initialized, because otherwise compilations of
734 // signature polymorphic MH intrinsics can be missed
735 // (see SystemDictionary::find_method_handle_intrinsic).
736 initialize_jsr292_core_classes(CHECK_JNI_ERR);
737
738 // This will initialize the module system. Only java.base classes can be
739 // loaded until phase 2 completes
740 call_initPhase2(CHECK_JNI_ERR);
741
742 JFR_ONLY(Jfr::on_create_vm_2();)
743
744 // Always call even when there are not JVMTI environments yet, since environments
745 // may be attached late and JVMTI must track phases of VM execution
746 JvmtiExport::enter_start_phase();
747
748 // Notify JVMTI agents that VM has started (JNI is up) - nop if no agents.
749 JvmtiExport::post_vm_start();
750
751 // Final system initialization including security manager and system class loader
752 call_initPhase3(CHECK_JNI_ERR);
753
754 // cache the system and platform class loaders
755 SystemDictionary::compute_java_loaders(CHECK_JNI_ERR);
756
757 if (Continuations::enabled()) {
758 // Initialize Continuation class now so that failure to create enterSpecial/doYield
759 // special nmethods due to limited CodeCache size can be treated as a fatal error at
760 // startup with the proper message that CodeCache size is too small.
761 initialize_class(vmSymbols::jdk_internal_vm_Continuation(), CHECK_JNI_ERR);
762 }
763
764 #if INCLUDE_CDS
765 // capture the module path info from the ModuleEntryTable
766 ClassLoader::initialize_module_path(THREAD);
767 if (HAS_PENDING_EXCEPTION) {
768 java_lang_Throwable::print(PENDING_EXCEPTION, tty);
769 vm_exit_during_initialization("ClassLoader::initialize_module_path() failed unexpectedly");
770 }
771 #endif
772
773 #if INCLUDE_JVMCI
774 if (force_JVMCI_initialization) {
775 JVMCI::initialize_compiler(CHECK_JNI_ERR);
776 }
777 #endif
778
779 if (NativeHeapTrimmer::enabled()) {
780 NativeHeapTrimmer::initialize();
781 }
782
783 // Always call even when there are not JVMTI environments yet, since environments
784 // may be attached late and JVMTI must track phases of VM execution
785 JvmtiExport::enter_live_phase();
786
787 // Make perfmemory accessible
788 PerfMemory::set_accessible(true);
789
790 // Notify JVMTI agents that VM initialization is complete - nop if no agents.
791 JvmtiExport::post_vm_initialized();
792
793 JFR_ONLY(Jfr::on_create_vm_3();)
794
795 #if INCLUDE_MANAGEMENT
796 Management::initialize(THREAD);
797
798 if (HAS_PENDING_EXCEPTION) {
799 // management agent fails to start possibly due to
800 // configuration problem and is responsible for printing
801 // stack trace if appropriate. Simply exit VM.
802 vm_exit(1);
803 }
804 #endif // INCLUDE_MANAGEMENT
805
806 StatSampler::engage();
807 if (CheckJNICalls) JniPeriodicChecker::engage();
808
809 call_postVMInitHook(THREAD);
810 // The Java side of PostVMInitHook.run must deal with all
811 // exceptions and provide means of diagnosis.
812 if (HAS_PENDING_EXCEPTION) {
813 CLEAR_PENDING_EXCEPTION;
814 }
815
816 // Let WatcherThread run all registered periodic tasks now.
817 // NOTE: All PeriodicTasks should be registered by now. If they
818 // aren't, late joiners might appear to start slowly (we might
819 // take a while to process their first tick).
820 WatcherThread::run_all_tasks();
821
822 create_vm_timer.end();
823 #ifdef ASSERT
824 _vm_complete = true;
825 #endif
826
827 if (CDSConfig::is_dumping_static_archive()) {
828 MetaspaceShared::preload_and_dump(CHECK_JNI_ERR);
829 }
830
831 if (log_is_enabled(Info, perf, class, link)) {
832 LogStreamHandle(Info, perf, class, link) log;
833 log.print_cr("At VM initialization completion:");
834 ClassLoader::print_counters(&log);
835 }
836
837 return JNI_OK;
838 }
839
840 // Threads::destroy_vm() is normally called from jni_DestroyJavaVM() when
841 // the program falls off the end of main(). Another VM exit path is through
842 // vm_exit(), when the program calls System.exit() to return a value, or when
843 // there is a serious error in VM.
844 // These two separate shutdown paths are not exactly the same, but they share
845 // Shutdown.shutdown() at Java level and before_exit() and VM_Exit op at VM level.
846 //
847 // Shutdown sequence:
848 // + Shutdown native memory tracking if it is on
849 // + Wait until we are the last non-daemon thread to execute
850 // <-- every thing is still working at this moment -->
851 // + Call java.lang.Shutdown.shutdown(), which will invoke Java level
852 // shutdown hooks
853 // + Call before_exit(), prepare for VM exit
854 // > run VM level shutdown hooks (they are registered through JVM_OnExit(),
855 // currently the only user of this mechanism is File.deleteOnExit())
856 // > stop StatSampler, watcher thread,
857 // post thread end and vm death events to JVMTI,
858 // stop signal thread
859 // + Call JavaThread::exit(), it will:
860 // > release JNI handle blocks, remove stack guard pages
861 // > remove this thread from Threads list
862 // <-- no more Java code from this thread after this point -->
863 // + Stop VM thread, it will bring the remaining VM to a safepoint and stop
864 // the compiler threads at safepoint
865 // <-- do not use anything that could get blocked by Safepoint -->
866 // + Disable tracing at JNI/JVM barriers
867 // + Set _vm_exited flag for threads that are still running native code
868 // + Call exit_globals()
869 // > deletes tty
870 // > deletes PerfMemory resources
871 // + Delete this thread
872 // + Return to caller
873
874 void Threads::destroy_vm() {
875 JavaThread* thread = JavaThread::current();
876
877 #ifdef ASSERT
878 _vm_complete = false;
879 #endif
880 // Wait until we are the last non-daemon thread to execute, or
881 // if we are a daemon then wait until the last non-daemon thread has
882 // executed.
883 bool daemon = java_lang_Thread::is_daemon(thread->threadObj());
884 int expected = daemon ? 0 : 1;
885 {
886 MonitorLocker nu(Threads_lock);
887 while (Threads::number_of_non_daemon_threads() > expected)
888 // This wait should make safepoint checks, wait without a timeout.
889 nu.wait(0);
890 }
891
892 EventShutdown e;
893 if (e.should_commit()) {
894 e.set_reason("No remaining non-daemon Java threads");
895 e.commit();
896 }
897
898 // Hang forever on exit if we are reporting an error.
899 if (ShowMessageBoxOnError && VMError::is_error_reported()) {
900 os::infinite_sleep();
901 }
902 os::wait_for_keypress_at_exit();
903
904 // run Java level shutdown hooks
905 thread->invoke_shutdown_hooks();
906
907 before_exit(thread);
908
909 thread->exit(true);
910
911 // We are no longer on the main thread list but could still be in a
912 // secondary list where another thread may try to interact with us.
913 // So wait until all such interactions are complete before we bring
914 // the VM to the termination safepoint. Normally this would be done
915 // using thread->smr_delete() below where we delete the thread, but
916 // we can't call that after the termination safepoint is active as
917 // we will deadlock on the Threads_lock. Once all interactions are
918 // complete it is safe to directly delete the thread at any time.
919 ThreadsSMRSupport::wait_until_not_protected(thread);
920
921 // Stop VM thread.
922 {
923 // 4945125 The vm thread comes to a safepoint during exit.
924 // GC vm_operations can get caught at the safepoint, and the
925 // heap is unparseable if they are caught. Grab the Heap_lock
926 // to prevent this. The GC vm_operations will not be able to
927 // queue until after the vm thread is dead. After this point,
928 // we'll never emerge out of the safepoint before the VM exits.
929 // Assert that the thread is terminated so that acquiring the
930 // Heap_lock doesn't cause the terminated thread to participate in
931 // the safepoint protocol.
932
933 assert(thread->is_terminated(), "must be terminated here");
934 MutexLocker ml(Heap_lock);
935
936 VMThread::wait_for_vm_thread_exit();
937 assert(SafepointSynchronize::is_at_safepoint(), "VM thread should exit at Safepoint");
938 VMThread::destroy();
939 }
940
941 // Now, all Java threads are gone except daemon threads. Daemon threads
942 // running Java code or in VM are stopped by the Safepoint. However,
943 // daemon threads executing native code are still running. But they
944 // will be stopped at native=>Java/VM barriers. Note that we can't
945 // simply kill or suspend them, as it is inherently deadlock-prone.
946
947 VM_Exit::set_vm_exited();
948
949 // Clean up ideal graph printers after the VMThread has started
950 // the final safepoint which will block all the Compiler threads.
951 // Note that this Thread has already logically exited so the
952 // clean_up() function's use of a JavaThreadIteratorWithHandle
953 // would be a problem except set_vm_exited() has remembered the
954 // shutdown thread which is granted a policy exception.
955 #if defined(COMPILER2) && !defined(PRODUCT)
956 IdealGraphPrinter::clean_up();
957 #endif
958
959 notify_vm_shutdown();
960
961 // exit_globals() will delete tty
962 exit_globals();
963
964 // Deleting the shutdown thread here is safe. See comment on
965 // wait_until_not_protected() above.
966 delete thread;
967
968 #if INCLUDE_JVMCI
969 if (JVMCICounterSize > 0) {
970 FREE_C_HEAP_ARRAY(jlong, JavaThread::_jvmci_old_thread_counters);
971 }
972 #endif
973
974 LogConfiguration::finalize();
975 }
976
977
978 jboolean Threads::is_supported_jni_version_including_1_1(jint version) {
979 if (version == JNI_VERSION_1_1) return JNI_TRUE;
980 return is_supported_jni_version(version);
981 }
982
983
984 jboolean Threads::is_supported_jni_version(jint version) {
985 if (version == JNI_VERSION_1_2) return JNI_TRUE;
986 if (version == JNI_VERSION_1_4) return JNI_TRUE;
987 if (version == JNI_VERSION_1_6) return JNI_TRUE;
988 if (version == JNI_VERSION_1_8) return JNI_TRUE;
989 if (version == JNI_VERSION_9) return JNI_TRUE;
990 if (version == JNI_VERSION_10) return JNI_TRUE;
991 if (version == JNI_VERSION_19) return JNI_TRUE;
992 if (version == JNI_VERSION_20) return JNI_TRUE;
993 if (version == JNI_VERSION_21) return JNI_TRUE;
994 if (version == JNI_VERSION_24) return JNI_TRUE;
995 return JNI_FALSE;
996 }
997
998 void Threads::add(JavaThread* p, bool force_daemon) {
999 // The threads lock must be owned at this point
1000 assert(Threads_lock->owned_by_self(), "must have threads lock");
1001
1002 BarrierSet::barrier_set()->on_thread_attach(p);
1003
1004 // Once a JavaThread is added to the Threads list, smr_delete() has
1005 // to be used to delete it. Otherwise we can just delete it directly.
1006 p->set_on_thread_list();
1007
1008 _number_of_threads++;
1009 oop threadObj = p->threadObj();
1010 bool daemon = true;
1011 // Bootstrapping problem: threadObj can be null for initial
1012 // JavaThread (or for threads attached via JNI)
1013 if (!force_daemon &&
1014 (threadObj == nullptr || !java_lang_Thread::is_daemon(threadObj))) {
1015 _number_of_non_daemon_threads++;
1016 daemon = false;
1017 }
1018
1019 ThreadService::add_thread(p, daemon);
1020
1021 // Maintain fast thread list
1022 ThreadsSMRSupport::add_thread(p);
1023
1024 // Increase the ObjectMonitor ceiling for the new thread.
1025 ObjectSynchronizer::inc_in_use_list_ceiling();
1026
1027 // Possible GC point.
1028 Events::log(Thread::current(), "Thread added: " INTPTR_FORMAT, p2i(p));
1029
1030 // Make new thread known to active EscapeBarrier
1031 EscapeBarrier::thread_added(p);
1032 }
1033
1034 void Threads::remove(JavaThread* p, bool is_daemon) {
1035 // Extra scope needed for Thread_lock, so we can check
1036 // that we do not remove thread without safepoint code notice
1037 {
1038 ConditionalMutexLocker throttle_ml(ThreadsLockThrottle_lock, UseThreadsLockThrottleLock);
1039 MonitorLocker ml(Threads_lock);
1040
1041 if (ThreadIdTable::is_initialized()) {
1042 // This cleanup must be done before the current thread's GC barrier
1043 // is detached since we need to touch the threadObj oop.
1044 jlong tid = SharedRuntime::get_java_tid(p);
1045 ThreadIdTable::remove_thread(tid);
1046 }
1047
1048 // BarrierSet state must be destroyed after the last thread transition
1049 // before the thread terminates. Thread transitions result in calls to
1050 // StackWatermarkSet::on_safepoint(), which performs GC processing,
1051 // requiring the GC state to be alive.
1052 BarrierSet::barrier_set()->on_thread_detach(p);
1053 if (p->is_exiting()) {
1054 // If we got here via JavaThread::exit(), then we remember that the
1055 // thread's GC barrier has been detached. We don't do this when we get
1056 // here from another path, e.g., cleanup_failed_attach_current_thread().
1057 p->set_terminated(JavaThread::_thread_gc_barrier_detached);
1058 }
1059
1060 assert(ThreadsSMRSupport::get_java_thread_list()->includes(p), "p must be present");
1061
1062 // Maintain fast thread list
1063 ThreadsSMRSupport::remove_thread(p);
1064
1065 _number_of_threads--;
1066 if (!is_daemon) {
1067 _number_of_non_daemon_threads--;
1068
1069 // If this is the last non-daemon thread then we need to do
1070 // a notify on the Threads_lock so a thread waiting
1071 // on destroy_vm will wake up. But that thread could be a daemon
1072 // or non-daemon, so we notify for both the 0 and 1 case.
1073 if (number_of_non_daemon_threads() <= 1) {
1074 ml.notify_all();
1075 }
1076 }
1077 ThreadService::remove_thread(p, is_daemon);
1078
1079 // Make sure that safepoint code disregard this thread. This is needed since
1080 // the thread might mess around with locks after this point. This can cause it
1081 // to do callbacks into the safepoint code. However, the safepoint code is not aware
1082 // of this thread since it is removed from the queue.
1083 p->set_terminated(JavaThread::_thread_terminated);
1084
1085 // Notify threads waiting in EscapeBarriers
1086 EscapeBarrier::thread_removed(p);
1087 } // unlock Threads_lock and ThreadsLockThrottle_lock
1088
1089 // Reduce the ObjectMonitor ceiling for the exiting thread.
1090 ObjectSynchronizer::dec_in_use_list_ceiling();
1091
1092 // Since Events::log uses a lock, we grab it outside the Threads_lock
1093 Events::log(Thread::current(), "Thread exited: " INTPTR_FORMAT, p2i(p));
1094 }
1095
1096 // Operations on the Threads list for GC. These are not explicitly locked,
1097 // but the garbage collector must provide a safe context for them to run.
1098 // In particular, these things should never be called when the Threads_lock
1099 // is held by some other thread. (Note: the Safepoint abstraction also
1100 // uses the Threads_lock to guarantee this property. It also makes sure that
1101 // all threads gets blocked when exiting or starting).
1102
1103 void Threads::oops_do(OopClosure* f, NMethodClosure* cf) {
1104 ALL_JAVA_THREADS(p) {
1105 p->oops_do(f, cf);
1106 }
1107 VMThread::vm_thread()->oops_do(f, cf);
1108 }
1109
1110 void Threads::change_thread_claim_token() {
1111 if (++_thread_claim_token == 0) {
1112 // On overflow of the token counter, there is a risk of future
1113 // collisions between a new global token value and a stale token
1114 // for a thread, because not all iterations visit all threads.
1115 // (Though it's pretty much a theoretical concern for non-trivial
1116 // token counter sizes.) To deal with the possibility, reset all
1117 // the thread tokens to zero on global token overflow.
1118 struct ResetClaims : public ThreadClosure {
1119 virtual void do_thread(Thread* t) {
1120 t->claim_threads_do(false, 0);
1121 }
1122 } reset_claims;
1123 Threads::threads_do(&reset_claims);
1124 // On overflow, update the global token to non-zero, to
1125 // avoid the special "never claimed" initial thread value.
1126 _thread_claim_token = 1;
1127 }
1128 }
1129
1130 #ifdef ASSERT
1131 static void assert_thread_claimed(const char* kind, Thread* t, uintx expected) {
1132 const uintx token = t->threads_do_token();
1133 assert(token == expected,
1134 "%s " PTR_FORMAT " has incorrect value " UINTX_FORMAT " != "
1135 UINTX_FORMAT, kind, p2i(t), token, expected);
1136 }
1137
1138 void Threads::assert_all_threads_claimed() {
1139 ALL_JAVA_THREADS(p) {
1140 assert_thread_claimed("JavaThread", p, _thread_claim_token);
1141 }
1142
1143 struct NJTClaimedVerifierClosure : public ThreadClosure {
1144 uintx _thread_claim_token;
1145
1146 NJTClaimedVerifierClosure(uintx thread_claim_token) : ThreadClosure(), _thread_claim_token(thread_claim_token) { }
1147
1148 virtual void do_thread(Thread* thread) override {
1149 assert_thread_claimed("Non-JavaThread", VMThread::vm_thread(), _thread_claim_token);
1150 }
1151 } tc(_thread_claim_token);
1152
1153 non_java_threads_do(&tc);
1154 }
1155 #endif // ASSERT
1156
1157 class ParallelOopsDoThreadClosure : public ThreadClosure {
1158 private:
1159 OopClosure* _f;
1160 NMethodClosure* _cf;
1161 public:
1162 ParallelOopsDoThreadClosure(OopClosure* f, NMethodClosure* cf) : _f(f), _cf(cf) {}
1163 void do_thread(Thread* t) {
1164 t->oops_do(_f, _cf);
1165 }
1166 };
1167
1168 void Threads::possibly_parallel_oops_do(bool is_par, OopClosure* f, NMethodClosure* cf) {
1169 ParallelOopsDoThreadClosure tc(f, cf);
1170 possibly_parallel_threads_do(is_par, &tc);
1171 }
1172
1173 void Threads::metadata_do(MetadataClosure* f) {
1174 ALL_JAVA_THREADS(p) {
1175 p->metadata_do(f);
1176 }
1177 }
1178
1179 class ThreadHandlesClosure : public ThreadClosure {
1180 void (*_f)(Metadata*);
1181 public:
1182 ThreadHandlesClosure(void f(Metadata*)) : _f(f) {}
1183 virtual void do_thread(Thread* thread) {
1184 thread->metadata_handles_do(_f);
1185 }
1186 };
1187
1188 void Threads::metadata_handles_do(void f(Metadata*)) {
1189 // Only walk the Handles in Thread.
1190 ThreadHandlesClosure handles_closure(f);
1191 threads_do(&handles_closure);
1192 }
1193
1194 #if INCLUDE_JVMTI
1195 // Get Java threads that are waiting to enter or re-enter the specified monitor.
1196 // Java threads that are executing mounted virtual threads are not included.
1197 GrowableArray<JavaThread*>* Threads::get_pending_threads(ThreadsList * t_list,
1198 int count,
1199 address monitor) {
1200 assert(Thread::current()->is_VM_thread(), "Must be the VM thread");
1201 GrowableArray<JavaThread*>* result = new GrowableArray<JavaThread*>(count);
1202
1203 int i = 0;
1204 for (JavaThread* p : *t_list) {
1205 if (!p->can_call_java()) continue;
1206
1207 oop thread_oop = JvmtiEnvBase::get_vthread_or_thread_oop(p);
1208 if (thread_oop->is_a(vmClasses::BaseVirtualThread_klass())) {
1209 continue;
1210 }
1211 // The first stage of async deflation does not affect any field
1212 // used by this comparison so the ObjectMonitor* is usable here.
1213 address pending = (address)p->current_pending_monitor();
1214 address waiting = (address)p->current_waiting_monitor();
1215 // do not include virtual threads to the list
1216 jint state = JvmtiEnvBase::get_thread_state(thread_oop, p);
1217 if (pending == monitor || (waiting == monitor &&
1218 (state & JVMTI_THREAD_STATE_BLOCKED_ON_MONITOR_ENTER))
1219 ) { // found a match
1220 if (i < count) result->append(p); // save the first count matches
1221 i++;
1222 }
1223 }
1224
1225 return result;
1226 }
1227 #endif // INCLUDE_JVMTI
1228
1229 JavaThread *Threads::owning_thread_from_monitor_owner(ThreadsList * t_list,
1230 address owner) {
1231 assert(LockingMode != LM_LIGHTWEIGHT, "Not with new lightweight locking");
1232 // null owner means not locked so we can skip the search
1233 if (owner == nullptr) return nullptr;
1234
1235 for (JavaThread* p : *t_list) {
1236 // first, see if owner is the address of a Java thread
1237 if (owner == (address)p) return p;
1238 }
1239
1240 // Cannot assert on lack of success here since this function may be
1241 // used by code that is trying to report useful problem information
1242 // like deadlock detection.
1243 if (LockingMode == LM_MONITOR) return nullptr;
1244
1245 // If we didn't find a matching Java thread and we didn't force use of
1246 // heavyweight monitors, then the owner is the stack address of the
1247 // Lock Word in the owning Java thread's stack.
1248 //
1249 JavaThread* the_owner = nullptr;
1250 for (JavaThread* q : *t_list) {
1251 if (q->is_lock_owned(owner)) {
1252 the_owner = q;
1253 break;
1254 }
1255 }
1256
1257 // cannot assert on lack of success here; see above comment
1258 return the_owner;
1259 }
1260
1261 JavaThread* Threads::owning_thread_from_object(ThreadsList * t_list, oop obj) {
1262 assert(LockingMode == LM_LIGHTWEIGHT, "Only with new lightweight locking");
1263 for (JavaThread* q : *t_list) {
1264 // Need to start processing before accessing oops in the thread.
1265 StackWatermark* watermark = StackWatermarkSet::get(q, StackWatermarkKind::gc);
1266 if (watermark != nullptr) {
1267 watermark->start_processing();
1268 }
1269
1270 if (q->lock_stack().contains(obj)) {
1271 return q;
1272 }
1273 }
1274 return nullptr;
1275 }
1276
1277 JavaThread* Threads::owning_thread_from_monitor(ThreadsList* t_list, ObjectMonitor* monitor) {
1278 if (LockingMode == LM_LIGHTWEIGHT) {
1279 if (monitor->is_owner_anonymous()) {
1280 return owning_thread_from_object(t_list, monitor->object());
1281 } else {
1282 Thread* owner = reinterpret_cast<Thread*>(monitor->owner());
1283 assert(owner == nullptr || owner->is_Java_thread(), "only JavaThreads own monitors");
1284 return reinterpret_cast<JavaThread*>(owner);
1285 }
1286 } else {
1287 address owner = (address)monitor->owner();
1288 return owning_thread_from_monitor_owner(t_list, owner);
1289 }
1290 }
1291
1292 class PrintOnClosure : public ThreadClosure {
1293 private:
1294 outputStream* _st;
1295
1296 public:
1297 PrintOnClosure(outputStream* st) :
1298 _st(st) {}
1299
1300 virtual void do_thread(Thread* thread) {
1301 if (thread != nullptr) {
1302 thread->print_on(_st);
1303 _st->cr();
1304 }
1305 }
1306 };
1307
1308 // Threads::print_on() is called at safepoint by VM_PrintThreads operation.
1309 void Threads::print_on(outputStream* st, bool print_stacks,
1310 bool internal_format, bool print_concurrent_locks,
1311 bool print_extended_info) {
1312 char buf[32];
1313 st->print_raw_cr(os::local_time_string(buf, sizeof(buf)));
1314
1315 st->print_cr("Full thread dump %s (%s %s):",
1316 VM_Version::vm_name(),
1317 VM_Version::vm_release(),
1318 VM_Version::vm_info_string());
1319 st->cr();
1320
1321 #if INCLUDE_SERVICES
1322 // Dump concurrent locks
1323 ConcurrentLocksDump concurrent_locks;
1324 if (print_concurrent_locks) {
1325 concurrent_locks.dump_at_safepoint();
1326 }
1327 #endif // INCLUDE_SERVICES
1328
1329 ThreadsSMRSupport::print_info_on(st);
1330 st->cr();
1331
1332 ALL_JAVA_THREADS(p) {
1333 ResourceMark rm;
1334 p->print_on(st, print_extended_info);
1335 if (print_stacks) {
1336 if (internal_format) {
1337 p->trace_stack();
1338 } else {
1339 p->print_stack_on(st);
1340 const oop thread_oop = p->threadObj();
1341 if (thread_oop != nullptr) {
1342 if (p->is_vthread_mounted()) {
1343 const oop vt = p->vthread();
1344 assert(vt != nullptr, "vthread should not be null when vthread is mounted");
1345 // JavaThread._vthread can refer to the carrier thread. Print only if _vthread refers to a virtual thread.
1346 if (vt != thread_oop) {
1347 st->print_cr(" Mounted virtual thread #" INT64_FORMAT, (int64_t)java_lang_Thread::thread_id(vt));
1348 p->print_vthread_stack_on(st);
1349 }
1350 }
1351 }
1352 }
1353 }
1354 st->cr();
1355 #if INCLUDE_SERVICES
1356 if (print_concurrent_locks) {
1357 concurrent_locks.print_locks_on(p, st);
1358 }
1359 #endif // INCLUDE_SERVICES
1360 }
1361
1362 PrintOnClosure cl(st);
1363 non_java_threads_do(&cl);
1364
1365 st->flush();
1366 }
1367
1368 void Threads::print_on_error(Thread* this_thread, outputStream* st, Thread* current, char* buf,
1369 int buflen, bool* found_current) {
1370 if (this_thread != nullptr) {
1371 bool is_current = (current == this_thread);
1372 *found_current = *found_current || is_current;
1373 st->print("%s", is_current ? "=>" : " ");
1374
1375 st->print(PTR_FORMAT, p2i(this_thread));
1376 st->print(" ");
1377 this_thread->print_on_error(st, buf, buflen);
1378 st->cr();
1379 }
1380 }
1381
1382 class PrintOnErrorClosure : public ThreadClosure {
1383 outputStream* _st;
1384 Thread* _current;
1385 char* _buf;
1386 int _buflen;
1387 bool* _found_current;
1388 unsigned _num_printed;
1389 public:
1390 PrintOnErrorClosure(outputStream* st, Thread* current, char* buf,
1391 int buflen, bool* found_current) :
1392 _st(st), _current(current), _buf(buf), _buflen(buflen), _found_current(found_current),
1393 _num_printed(0) {}
1394
1395 virtual void do_thread(Thread* thread) {
1396 _num_printed++;
1397 Threads::print_on_error(thread, _st, _current, _buf, _buflen, _found_current);
1398 }
1399
1400 unsigned num_printed() const { return _num_printed; }
1401 };
1402
1403 // Threads::print_on_error() is called by fatal error handler. It's possible
1404 // that VM is not at safepoint and/or current thread is inside signal handler.
1405 // Don't print stack trace, as the stack may not be walkable. Don't allocate
1406 // memory (even in resource area), it might deadlock the error handler.
1407 void Threads::print_on_error(outputStream* st, Thread* current, char* buf,
1408 int buflen) {
1409 ThreadsSMRSupport::print_info_on(st);
1410 st->cr();
1411
1412 bool found_current = false;
1413 st->print_cr("Java Threads: ( => current thread )");
1414 unsigned num_java = 0;
1415 ALL_JAVA_THREADS(thread) {
1416 print_on_error(thread, st, current, buf, buflen, &found_current);
1417 num_java++;
1418 }
1419 st->print_cr("Total: %u", num_java);
1420 st->cr();
1421
1422 st->print_cr("Other Threads:");
1423 unsigned num_other = ((VMThread::vm_thread() != nullptr) ? 1 : 0) +
1424 ((WatcherThread::watcher_thread() != nullptr) ? 1 : 0) +
1425 ((AsyncLogWriter::instance() != nullptr) ? 1 : 0);
1426 print_on_error(VMThread::vm_thread(), st, current, buf, buflen, &found_current);
1427 print_on_error(WatcherThread::watcher_thread(), st, current, buf, buflen, &found_current);
1428 print_on_error(AsyncLogWriter::instance(), st, current, buf, buflen, &found_current);
1429
1430 if (Universe::heap() != nullptr) {
1431 PrintOnErrorClosure print_closure(st, current, buf, buflen, &found_current);
1432 Universe::heap()->gc_threads_do(&print_closure);
1433 num_other += print_closure.num_printed();
1434 }
1435
1436 if (!found_current) {
1437 st->cr();
1438 st->print("=>" PTR_FORMAT " (exited) ", p2i(current));
1439 current->print_on_error(st, buf, buflen);
1440 num_other++;
1441 st->cr();
1442 }
1443 st->print_cr("Total: %u", num_other);
1444 st->cr();
1445
1446 st->print_cr("Threads with active compile tasks:");
1447 unsigned num = print_threads_compiling(st, buf, buflen);
1448 st->print_cr("Total: %u", num);
1449 }
1450
1451 unsigned Threads::print_threads_compiling(outputStream* st, char* buf, int buflen, bool short_form) {
1452 unsigned num = 0;
1453 ALL_JAVA_THREADS(thread) {
1454 if (thread->is_Compiler_thread()) {
1455 CompilerThread* ct = (CompilerThread*) thread;
1456
1457 // Keep task in local variable for null check.
1458 // ct->_task might be set to null by concurring compiler thread
1459 // because it completed the compilation. The task is never freed,
1460 // though, just returned to a free list.
1461 CompileTask* task = ct->task();
1462 if (task != nullptr) {
1463 thread->print_name_on_error(st, buf, buflen);
1464 st->print(" ");
1465 task->print(st, nullptr, short_form, true);
1466 num++;
1467 }
1468 }
1469 }
1470 return num;
1471 }
1472
1473 void Threads::verify() {
1474 ALL_JAVA_THREADS(p) {
1475 p->verify();
1476 }
1477 VMThread* thread = VMThread::vm_thread();
1478 if (thread != nullptr) thread->verify();
1479 }