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/handles.inline.hpp" 69 #include "runtime/interfaceSupport.inline.hpp" 70 #include "runtime/java.hpp" 71 #include "runtime/javaCalls.hpp" 72 #include "runtime/javaThread.inline.hpp" 73 #include "runtime/jniHandles.inline.hpp" 74 #include "runtime/jniPeriodicChecker.hpp" 75 #include "runtime/lockStack.inline.hpp" 76 #include "runtime/monitorDeflationThread.hpp" 77 #include "runtime/mutexLocker.hpp" 78 #include "runtime/nonJavaThread.hpp" 79 #include "runtime/objectMonitor.inline.hpp" 80 #include "runtime/osThread.hpp" 81 #include "runtime/safepoint.hpp" 82 #include "runtime/safepointMechanism.inline.hpp" 83 #include "runtime/safepointVerifiers.hpp" 84 #include "runtime/serviceThread.hpp" 85 #include "runtime/sharedRuntime.hpp" 86 #include "runtime/stackWatermarkSet.inline.hpp" 87 #include "runtime/statSampler.hpp" 88 #include "runtime/stubCodeGenerator.hpp" 89 #include "runtime/thread.inline.hpp" 90 #include "runtime/threadSMR.inline.hpp" 91 #include "runtime/threads.hpp" 92 #include "runtime/timer.hpp" 93 #include "runtime/timerTrace.hpp" 94 #include "runtime/trimNativeHeap.hpp" 95 #include "runtime/vmOperations.hpp" 96 #include "runtime/vm_version.hpp" 97 #include "services/attachListener.hpp" 98 #include "services/management.hpp" 99 #include "services/threadIdTable.hpp" 100 #include "services/threadService.hpp" 101 #include "utilities/dtrace.hpp" 102 #include "utilities/events.hpp" 103 #include "utilities/macros.hpp" 104 #include "utilities/vmError.hpp" 105 #if INCLUDE_JVMCI 106 #include "jvmci/jvmci.hpp" 107 #include "jvmci/jvmciEnv.hpp" 108 #endif 109 #ifdef COMPILER2 110 #include "opto/idealGraphPrinter.hpp" 111 #endif 112 #if INCLUDE_JFR 113 #include "jfr/jfr.hpp" 114 #endif 115 116 // Initialization after module runtime initialization 117 void universe_post_module_init(); // must happen after call_initPhase2 118 119 120 static void initialize_class(Symbol* class_name, TRAPS) { 121 Klass* klass = SystemDictionary::resolve_or_fail(class_name, true, CHECK); 122 InstanceKlass::cast(klass)->initialize(CHECK); 123 } 124 125 126 // Creates the initial ThreadGroup 127 static Handle create_initial_thread_group(TRAPS) { 128 Handle system_instance = JavaCalls::construct_new_instance( 129 vmClasses::ThreadGroup_klass(), 130 vmSymbols::void_method_signature(), 131 CHECK_NH); 132 Universe::set_system_thread_group(system_instance()); 133 134 Handle string = java_lang_String::create_from_str("main", CHECK_NH); 135 Handle main_instance = JavaCalls::construct_new_instance( 136 vmClasses::ThreadGroup_klass(), 137 vmSymbols::threadgroup_string_void_signature(), 138 system_instance, 139 string, 140 CHECK_NH); 141 return main_instance; 142 } 143 144 // Creates the initial Thread, and sets it to running. 145 static void create_initial_thread(Handle thread_group, JavaThread* thread, 146 TRAPS) { 147 InstanceKlass* ik = vmClasses::Thread_klass(); 148 assert(ik->is_initialized(), "must be"); 149 instanceHandle thread_oop = ik->allocate_instance_handle(CHECK); 150 151 // Cannot use JavaCalls::construct_new_instance because the java.lang.Thread 152 // constructor calls Thread.current(), which must be set here for the 153 // initial thread. 154 java_lang_Thread::set_thread(thread_oop(), thread); 155 thread->set_threadOopHandles(thread_oop()); 156 157 Handle string = java_lang_String::create_from_str("main", CHECK); 158 159 JavaValue result(T_VOID); 160 JavaCalls::call_special(&result, thread_oop, 161 ik, 162 vmSymbols::object_initializer_name(), 163 vmSymbols::threadgroup_string_void_signature(), 164 thread_group, 165 string, 166 CHECK); 167 168 // Set thread status to running since main thread has 169 // been started and running. 170 java_lang_Thread::set_thread_status(thread_oop(), 171 JavaThreadStatus::RUNNABLE); 172 } 173 174 // Extract version and vendor specific information from 175 // java.lang.VersionProps fields. 176 // Returned char* is allocated in the thread's resource area 177 // so must be copied for permanency. 178 static const char* get_java_version_info(InstanceKlass* ik, 179 Symbol* field_name) { 180 fieldDescriptor fd; 181 bool found = ik != nullptr && 182 ik->find_local_field(field_name, 183 vmSymbols::string_signature(), &fd); 184 if (found) { 185 oop name_oop = ik->java_mirror()->obj_field(fd.offset()); 186 if (name_oop == nullptr) { 187 return nullptr; 188 } 189 const char* name = java_lang_String::as_utf8_string(name_oop); 190 return name; 191 } else { 192 return nullptr; 193 } 194 } 195 196 // ======= Threads ======== 197 198 // The Threads class links together all active threads, and provides 199 // operations over all threads. It is protected by the Threads_lock, 200 // which is also used in other global contexts like safepointing. 201 // ThreadsListHandles are used to safely perform operations on one 202 // or more threads without the risk of the thread exiting during the 203 // operation. 204 // 205 // Note: The Threads_lock is currently more widely used than we 206 // would like. We are actively migrating Threads_lock uses to other 207 // mechanisms in order to reduce Threads_lock contention. 208 209 int Threads::_number_of_threads = 0; 210 int Threads::_number_of_non_daemon_threads = 0; 211 int Threads::_return_code = 0; 212 uintx Threads::_thread_claim_token = 1; // Never zero. 213 214 #ifdef ASSERT 215 bool Threads::_vm_complete = false; 216 #endif 217 218 // General purpose hook into Java code, run once when the VM is initialized. 219 // The Java library method itself may be changed independently from the VM. 220 static void call_postVMInitHook(TRAPS) { 221 Klass* klass = SystemDictionary::resolve_or_null(vmSymbols::jdk_internal_vm_PostVMInitHook(), THREAD); 222 if (klass != nullptr) { 223 JavaValue result(T_VOID); 224 JavaCalls::call_static(&result, klass, vmSymbols::run_method_name(), 225 vmSymbols::void_method_signature(), 226 CHECK); 227 } 228 } 229 230 // All NonJavaThreads (i.e., every non-JavaThread in the system). 231 void Threads::non_java_threads_do(ThreadClosure* tc) { 232 NoSafepointVerifier nsv; 233 for (NonJavaThread::Iterator njti; !njti.end(); njti.step()) { 234 tc->do_thread(njti.current()); 235 } 236 } 237 238 // All JavaThreads 239 #define ALL_JAVA_THREADS(X) \ 240 for (JavaThread* X : *ThreadsSMRSupport::get_java_thread_list()) 241 242 // All JavaThreads 243 void Threads::java_threads_do(ThreadClosure* tc) { 244 assert_locked_or_safepoint(Threads_lock); 245 // ALL_JAVA_THREADS iterates through all JavaThreads. 246 ALL_JAVA_THREADS(p) { 247 tc->do_thread(p); 248 } 249 } 250 251 // All JavaThreads + all non-JavaThreads (i.e., every thread in the system). 252 void Threads::threads_do(ThreadClosure* tc) { 253 assert_locked_or_safepoint(Threads_lock); 254 java_threads_do(tc); 255 non_java_threads_do(tc); 256 } 257 258 void Threads::possibly_parallel_threads_do(bool is_par, ThreadClosure* tc) { 259 assert_at_safepoint(); 260 261 uintx claim_token = Threads::thread_claim_token(); 262 ALL_JAVA_THREADS(p) { 263 if (p->claim_threads_do(is_par, claim_token)) { 264 tc->do_thread(p); 265 } 266 } 267 for (NonJavaThread::Iterator njti; !njti.end(); njti.step()) { 268 Thread* current = njti.current(); 269 if (current->claim_threads_do(is_par, claim_token)) { 270 tc->do_thread(current); 271 } 272 } 273 } 274 275 // The system initialization in the library has three phases. 276 // 277 // Phase 1: java.lang.System class initialization 278 // java.lang.System is a primordial class loaded and initialized 279 // by the VM early during startup. java.lang.System.<clinit> 280 // only does registerNatives and keeps the rest of the class 281 // initialization work later until thread initialization completes. 282 // 283 // System.initPhase1 initializes the system properties, the static 284 // fields in, out, and err. Set up java signal handlers, OS-specific 285 // system settings, and thread group of the main thread. 286 static void call_initPhase1(TRAPS) { 287 Klass* klass = vmClasses::System_klass(); 288 JavaValue result(T_VOID); 289 JavaCalls::call_static(&result, klass, vmSymbols::initPhase1_name(), 290 vmSymbols::void_method_signature(), CHECK); 291 } 292 293 // Phase 2. Module system initialization 294 // This will initialize the module system. Only java.base classes 295 // can be loaded until phase 2 completes. 296 // 297 // Call System.initPhase2 after the compiler initialization and jsr292 298 // classes get initialized because module initialization runs a lot of java 299 // code, that for performance reasons, should be compiled. Also, this will 300 // enable the startup code to use lambda and other language features in this 301 // phase and onward. 302 // 303 // After phase 2, The VM will begin search classes from -Xbootclasspath/a. 304 static void call_initPhase2(TRAPS) { 305 TraceTime timer("Initialize module system", TRACETIME_LOG(Info, startuptime)); 306 307 Klass* klass = vmClasses::System_klass(); 308 309 JavaValue result(T_INT); 310 JavaCallArguments args; 311 args.push_int(DisplayVMOutputToStderr); 312 args.push_int(log_is_enabled(Debug, init)); // print stack trace if exception thrown 313 JavaCalls::call_static(&result, klass, vmSymbols::initPhase2_name(), 314 vmSymbols::boolean_boolean_int_signature(), &args, CHECK); 315 if (result.get_jint() != JNI_OK) { 316 vm_exit_during_initialization(); // no message or exception 317 } 318 319 universe_post_module_init(); 320 } 321 322 // Phase 3. final setup - set security manager, system class loader and TCCL 323 // 324 // This will instantiate and set the security manager, set the system class 325 // loader as well as the thread context class loader. The security manager 326 // and system class loader may be a custom class loaded from -Xbootclasspath/a, 327 // other modules or the application's classpath. 328 static void call_initPhase3(TRAPS) { 329 Klass* klass = vmClasses::System_klass(); 330 JavaValue result(T_VOID); 331 JavaCalls::call_static(&result, klass, vmSymbols::initPhase3_name(), 332 vmSymbols::void_method_signature(), CHECK); 333 } 334 335 void Threads::initialize_java_lang_classes(JavaThread* main_thread, TRAPS) { 336 TraceTime timer("Initialize java.lang classes", TRACETIME_LOG(Info, startuptime)); 337 338 initialize_class(vmSymbols::java_lang_String(), CHECK); 339 340 // Inject CompactStrings value after the static initializers for String ran. 341 java_lang_String::set_compact_strings(CompactStrings); 342 343 // Initialize java_lang.System (needed before creating the thread) 344 initialize_class(vmSymbols::java_lang_System(), CHECK); 345 // The VM creates & returns objects of this class. Make sure it's initialized. 346 initialize_class(vmSymbols::java_lang_Class(), CHECK); 347 initialize_class(vmSymbols::java_lang_ThreadGroup(), CHECK); 348 Handle thread_group = create_initial_thread_group(CHECK); 349 Universe::set_main_thread_group(thread_group()); 350 initialize_class(vmSymbols::java_lang_Thread(), CHECK); 351 create_initial_thread(thread_group, main_thread, CHECK); 352 353 // The VM creates objects of this class. 354 initialize_class(vmSymbols::java_lang_Module(), CHECK); 355 356 #ifdef ASSERT 357 InstanceKlass *k = vmClasses::UnsafeConstants_klass(); 358 assert(k->is_not_initialized(), "UnsafeConstants should not already be initialized"); 359 #endif 360 361 // initialize the hardware-specific constants needed by Unsafe 362 initialize_class(vmSymbols::jdk_internal_misc_UnsafeConstants(), CHECK); 363 jdk_internal_misc_UnsafeConstants::set_unsafe_constants(); 364 365 // The VM preresolves methods to these classes. Make sure that they get initialized 366 initialize_class(vmSymbols::java_lang_reflect_Method(), CHECK); 367 initialize_class(vmSymbols::java_lang_ref_Finalizer(), CHECK); 368 369 // Phase 1 of the system initialization in the library, java.lang.System class initialization 370 call_initPhase1(CHECK); 371 372 // Get the Java runtime name, version, and vendor info after java.lang.System is initialized. 373 // Some values are actually configure-time constants but some can be set via the jlink tool and 374 // so must be read dynamically. We treat them all the same. 375 InstanceKlass* ik = SystemDictionary::find_instance_klass(THREAD, vmSymbols::java_lang_VersionProps(), 376 Handle(), Handle()); 377 { 378 ResourceMark rm(main_thread); 379 JDK_Version::set_java_version(get_java_version_info(ik, vmSymbols::java_version_name())); 380 381 JDK_Version::set_runtime_name(get_java_version_info(ik, vmSymbols::java_runtime_name_name())); 382 383 JDK_Version::set_runtime_version(get_java_version_info(ik, vmSymbols::java_runtime_version_name())); 384 385 JDK_Version::set_runtime_vendor_version(get_java_version_info(ik, vmSymbols::java_runtime_vendor_version_name())); 386 387 JDK_Version::set_runtime_vendor_vm_bug_url(get_java_version_info(ik, vmSymbols::java_runtime_vendor_vm_bug_url_name())); 388 } 389 390 // an instance of OutOfMemory exception has been allocated earlier 391 initialize_class(vmSymbols::java_lang_OutOfMemoryError(), CHECK); 392 initialize_class(vmSymbols::java_lang_NullPointerException(), CHECK); 393 initialize_class(vmSymbols::java_lang_ClassCastException(), CHECK); 394 initialize_class(vmSymbols::java_lang_ArrayStoreException(), CHECK); 395 initialize_class(vmSymbols::java_lang_ArithmeticException(), CHECK); 396 initialize_class(vmSymbols::java_lang_StackOverflowError(), CHECK); 397 initialize_class(vmSymbols::java_lang_IllegalMonitorStateException(), CHECK); 398 initialize_class(vmSymbols::java_lang_IllegalArgumentException(), CHECK); 399 } 400 401 void Threads::initialize_jsr292_core_classes(TRAPS) { 402 TraceTime timer("Initialize java.lang.invoke classes", TRACETIME_LOG(Info, startuptime)); 403 404 initialize_class(vmSymbols::java_lang_invoke_MethodHandle(), CHECK); 405 initialize_class(vmSymbols::java_lang_invoke_ResolvedMethodName(), CHECK); 406 initialize_class(vmSymbols::java_lang_invoke_MemberName(), CHECK); 407 initialize_class(vmSymbols::java_lang_invoke_MethodHandleNatives(), CHECK); 408 } 409 410 jint Threads::create_vm(JavaVMInitArgs* args, bool* canTryAgain) { 411 extern void JDK_Version_init(); 412 413 // Preinitialize version info. 414 VM_Version::early_initialize(); 415 416 // Check version 417 if (!is_supported_jni_version(args->version)) return JNI_EVERSION; 418 419 // Initialize library-based TLS 420 ThreadLocalStorage::init(); 421 422 // Initialize the output stream module 423 ostream_init(); 424 425 // Process java launcher properties. 426 Arguments::process_sun_java_launcher_properties(args); 427 428 // Initialize the os module 429 os::init(); 430 431 MACOS_AARCH64_ONLY(os::current_thread_enable_wx(WXWrite)); 432 433 // Record VM creation timing statistics 434 TraceVmCreationTime create_vm_timer; 435 create_vm_timer.start(); 436 437 // Initialize system properties. 438 Arguments::init_system_properties(); 439 440 // So that JDK version can be used as a discriminator when parsing arguments 441 JDK_Version_init(); 442 443 // Update/Initialize System properties after JDK version number is known 444 Arguments::init_version_specific_system_properties(); 445 446 // Make sure to initialize log configuration *before* parsing arguments 447 LogConfiguration::initialize(create_vm_timer.begin_time()); 448 449 // Parse arguments 450 // Note: this internally calls os::init_container_support() 451 jint parse_result = Arguments::parse(args); 452 if (parse_result != JNI_OK) return parse_result; 453 454 // Initialize NMT right after argument parsing to keep the pre-NMT-init window small. 455 MemTracker::initialize(); 456 457 os::init_before_ergo(); 458 459 jint ergo_result = Arguments::apply_ergo(); 460 if (ergo_result != JNI_OK) return ergo_result; 461 462 // Final check of all ranges after ergonomics which may change values. 463 if (!JVMFlagLimit::check_all_ranges()) { 464 return JNI_EINVAL; 465 } 466 467 // Final check of all 'AfterErgo' constraints after ergonomics which may change values. 468 bool constraint_result = JVMFlagLimit::check_all_constraints(JVMFlagConstraintPhase::AfterErgo); 469 if (!constraint_result) { 470 return JNI_EINVAL; 471 } 472 473 if (PauseAtStartup) { 474 os::pause(); 475 } 476 477 HOTSPOT_VM_INIT_BEGIN(); 478 479 // Timing (must come after argument parsing) 480 TraceTime timer("Create VM", TRACETIME_LOG(Info, startuptime)); 481 482 // Initialize the os module after parsing the args 483 jint os_init_2_result = os::init_2(); 484 if (os_init_2_result != JNI_OK) return os_init_2_result; 485 486 #ifdef CAN_SHOW_REGISTERS_ON_ASSERT 487 // Initialize assert poison page mechanism. 488 if (ShowRegistersOnAssert) { 489 initialize_assert_poison(); 490 } 491 #endif // CAN_SHOW_REGISTERS_ON_ASSERT 492 493 SafepointMechanism::initialize(); 494 495 jint adjust_after_os_result = Arguments::adjust_after_os(); 496 if (adjust_after_os_result != JNI_OK) return adjust_after_os_result; 497 498 // Initialize output stream logging 499 ostream_init_log(); 500 501 // Launch -agentlib/-agentpath and converted -Xrun agents 502 JvmtiAgentList::load_agents(); 503 504 // Initialize Threads state 505 _number_of_threads = 0; 506 _number_of_non_daemon_threads = 0; 507 508 // Initialize global data structures and create system classes in heap 509 vm_init_globals(); 510 511 #if INCLUDE_JVMCI 512 if (JVMCICounterSize > 0) { 513 JavaThread::_jvmci_old_thread_counters = NEW_C_HEAP_ARRAY(jlong, JVMCICounterSize, mtJVMCI); 514 memset(JavaThread::_jvmci_old_thread_counters, 0, sizeof(jlong) * JVMCICounterSize); 515 } else { 516 JavaThread::_jvmci_old_thread_counters = nullptr; 517 } 518 #endif // INCLUDE_JVMCI 519 520 // Initialize OopStorage for threadObj 521 JavaThread::_thread_oop_storage = OopStorageSet::create_strong("Thread OopStorage", mtThread); 522 523 // Attach the main thread to this os thread 524 JavaThread* main_thread = new JavaThread(); 525 main_thread->set_thread_state(_thread_in_vm); 526 main_thread->initialize_thread_current(); 527 // must do this before set_active_handles 528 main_thread->record_stack_base_and_size(); 529 main_thread->register_thread_stack_with_NMT(); 530 main_thread->set_active_handles(JNIHandleBlock::allocate_block()); 531 MACOS_AARCH64_ONLY(main_thread->init_wx()); 532 533 if (!main_thread->set_as_starting_thread()) { 534 vm_shutdown_during_initialization( 535 "Failed necessary internal allocation. Out of swap space"); 536 main_thread->smr_delete(); 537 *canTryAgain = false; // don't let caller call JNI_CreateJavaVM again 538 return JNI_ENOMEM; 539 } 540 541 // Enable guard page *after* os::create_main_thread(), otherwise it would 542 // crash Linux VM, see notes in os_linux.cpp. 543 main_thread->stack_overflow_state()->create_stack_guard_pages(); 544 545 // Initialize Java-Level synchronization subsystem 546 ObjectMonitor::Initialize(); 547 ObjectSynchronizer::initialize(); 548 549 // Initialize global modules 550 jint status = init_globals(); 551 if (status != JNI_OK) { 552 main_thread->smr_delete(); 553 *canTryAgain = false; // don't let caller call JNI_CreateJavaVM again 554 return status; 555 } 556 557 // Create WatcherThread as soon as we can since we need it in case 558 // of hangs during error reporting. 559 WatcherThread::start(); 560 561 // Add main_thread to threads list to finish barrier setup with 562 // on_thread_attach. Should be before starting to build Java objects in 563 // init_globals2, which invokes barriers. 564 { 565 MutexLocker mu(Threads_lock); 566 Threads::add(main_thread); 567 } 568 569 status = init_globals2(); 570 if (status != JNI_OK) { 571 Threads::remove(main_thread, false); 572 // It is possible that we managed to fully initialize Universe but have then 573 // failed by throwing an exception. In that case our caller JNI_CreateJavaVM 574 // will want to report it, so we can't delete the main thread. 575 if (!main_thread->has_pending_exception()) { 576 main_thread->smr_delete(); 577 } 578 *canTryAgain = false; // don't let caller call JNI_CreateJavaVM again 579 return status; 580 } 581 582 JFR_ONLY(Jfr::on_create_vm_1();) 583 584 // Should be done after the heap is fully created 585 main_thread->cache_global_variables(); 586 587 // Any JVMTI raw monitors entered in onload will transition into 588 // real raw monitor. VM is setup enough here for raw monitor enter. 589 JvmtiExport::transition_pending_onload_raw_monitors(); 590 591 // Create the VMThread 592 { TraceTime timer("Start VMThread", TRACETIME_LOG(Info, startuptime)); 593 594 VMThread::create(); 595 VMThread* vmthread = VMThread::vm_thread(); 596 597 if (!os::create_thread(vmthread, os::vm_thread)) { 598 vm_exit_during_initialization("Cannot create VM thread. " 599 "Out of system resources."); 600 } 601 602 // Wait for the VM thread to become ready, and VMThread::run to initialize 603 // Monitors can have spurious returns, must always check another state flag 604 { 605 MonitorLocker ml(Notify_lock); 606 os::start_thread(vmthread); 607 while (!vmthread->is_running()) { 608 ml.wait(); 609 } 610 } 611 } 612 613 assert(Universe::is_fully_initialized(), "not initialized"); 614 if (VerifyDuringStartup) { 615 // Make sure we're starting with a clean slate. 616 VM_Verify verify_op; 617 VMThread::execute(&verify_op); 618 } 619 620 // We need this to update the java.vm.info property in case any flags used 621 // to initially define it have been changed. This is needed for both CDS 622 // since UseSharedSpaces may be changed after java.vm.info 623 // is initially computed. See Abstract_VM_Version::vm_info_string(). 624 // This update must happen before we initialize the java classes, but 625 // after any initialization logic that might modify the flags. 626 Arguments::update_vm_info_property(VM_Version::vm_info_string()); 627 628 JavaThread* THREAD = JavaThread::current(); // For exception macros. 629 HandleMark hm(THREAD); 630 631 // Always call even when there are not JVMTI environments yet, since environments 632 // may be attached late and JVMTI must track phases of VM execution 633 JvmtiExport::enter_early_start_phase(); 634 635 // Notify JVMTI agents that VM has started (JNI is up) - nop if no agents. 636 JvmtiExport::post_early_vm_start(); 637 638 // Launch -Xrun agents early if EagerXrunInit is set 639 if (EagerXrunInit) { 640 JvmtiAgentList::load_xrun_agents(); 641 } 642 643 initialize_java_lang_classes(main_thread, CHECK_JNI_ERR); 644 645 quicken_jni_functions(); 646 647 // No more stub generation allowed after that point. 648 StubCodeDesc::freeze(); 649 650 // Set flag that basic initialization has completed. Used by exceptions and various 651 // debug stuff, that does not work until all basic classes have been initialized. 652 set_init_completed(); 653 654 LogConfiguration::post_initialize(); 655 Metaspace::post_initialize(); 656 MutexLockerImpl::post_initialize(); 657 658 HOTSPOT_VM_INIT_END(); 659 660 // record VM initialization completion time 661 #if INCLUDE_MANAGEMENT 662 Management::record_vm_init_completed(); 663 #endif // INCLUDE_MANAGEMENT 664 665 log_info(os)("Initialized VM with process ID %d", os::current_process_id()); 666 667 // Signal Dispatcher needs to be started before VMInit event is posted 668 os::initialize_jdk_signal_support(CHECK_JNI_ERR); 669 670 // Start Attach Listener if +StartAttachListener or it can't be started lazily 671 if (!DisableAttachMechanism) { 672 AttachListener::vm_start(); 673 if (StartAttachListener || AttachListener::init_at_startup()) { 674 AttachListener::init(); 675 } 676 } 677 678 // Launch -Xrun agents if EagerXrunInit is not set. 679 if (!EagerXrunInit) { 680 JvmtiAgentList::load_xrun_agents(); 681 } 682 683 Arena::start_chunk_pool_cleaner_task(); 684 685 // Start the service thread 686 // The service thread enqueues JVMTI deferred events and does various hashtable 687 // and other cleanups. Needs to start before the compilers start posting events. 688 ServiceThread::initialize(); 689 690 // Start the monitor deflation thread: 691 MonitorDeflationThread::initialize(); 692 693 // initialize compiler(s) 694 #if defined(COMPILER1) || COMPILER2_OR_JVMCI 695 bool init_compilation = true; 696 #if INCLUDE_JVMCI 697 bool force_JVMCI_initialization = false; 698 if (EnableJVMCI) { 699 // Initialize JVMCI eagerly when it is explicitly requested. 700 // Or when JVMCILibDumpJNIConfig or JVMCIPrintProperties is enabled. 701 force_JVMCI_initialization = EagerJVMCI || JVMCIPrintProperties || JVMCILibDumpJNIConfig; 702 if (!force_JVMCI_initialization && UseJVMCICompiler && !UseJVMCINativeLibrary && (!UseInterpreter || !BackgroundCompilation)) { 703 // Force initialization of jarjvmci otherwise requests for blocking 704 // compilations will not actually block until jarjvmci is initialized. 705 force_JVMCI_initialization = true; 706 } 707 if (JVMCIPrintProperties || JVMCILibDumpJNIConfig) { 708 // Both JVMCILibDumpJNIConfig and JVMCIPrintProperties exit the VM 709 // so compilation should be disabled. This prevents dumping or 710 // printing from happening more than once. 711 init_compilation = false; 712 } 713 } 714 #endif 715 if (init_compilation) { 716 CompileBroker::compilation_init(CHECK_JNI_ERR); 717 } 718 #endif 719 720 // Start string deduplication thread if requested. 721 if (StringDedup::is_enabled()) { 722 StringDedup::start(); 723 } 724 725 // Pre-initialize some JSR292 core classes to avoid deadlock during class loading. 726 // It is done after compilers are initialized, because otherwise compilations of 727 // signature polymorphic MH intrinsics can be missed 728 // (see SystemDictionary::find_method_handle_intrinsic). 729 initialize_jsr292_core_classes(CHECK_JNI_ERR); 730 731 // This will initialize the module system. Only java.base classes can be 732 // loaded until phase 2 completes 733 call_initPhase2(CHECK_JNI_ERR); 734 735 JFR_ONLY(Jfr::on_create_vm_2();) 736 737 // Always call even when there are not JVMTI environments yet, since environments 738 // may be attached late and JVMTI must track phases of VM execution 739 JvmtiExport::enter_start_phase(); 740 741 // Notify JVMTI agents that VM has started (JNI is up) - nop if no agents. 742 JvmtiExport::post_vm_start(); 743 744 // Final system initialization including security manager and system class loader 745 call_initPhase3(CHECK_JNI_ERR); 746 747 // cache the system and platform class loaders 748 SystemDictionary::compute_java_loaders(CHECK_JNI_ERR); 749 750 if (Continuations::enabled()) { 751 // Initialize Continuation class now so that failure to create enterSpecial/doYield 752 // special nmethods due to limited CodeCache size can be treated as a fatal error at 753 // startup with the proper message that CodeCache size is too small. 754 initialize_class(vmSymbols::jdk_internal_vm_Continuation(), CHECK_JNI_ERR); 755 } 756 757 #if INCLUDE_CDS 758 // capture the module path info from the ModuleEntryTable 759 ClassLoader::initialize_module_path(THREAD); 760 if (HAS_PENDING_EXCEPTION) { 761 java_lang_Throwable::print(PENDING_EXCEPTION, tty); 762 vm_exit_during_initialization("ClassLoader::initialize_module_path() failed unexpectedly"); 763 } 764 #endif 765 766 #if INCLUDE_JVMCI 767 if (force_JVMCI_initialization) { 768 JVMCI::initialize_compiler(CHECK_JNI_ERR); 769 } 770 #endif 771 772 if (NativeHeapTrimmer::enabled()) { 773 NativeHeapTrimmer::initialize(); 774 } 775 776 // Always call even when there are not JVMTI environments yet, since environments 777 // may be attached late and JVMTI must track phases of VM execution 778 JvmtiExport::enter_live_phase(); 779 780 // Make perfmemory accessible 781 PerfMemory::set_accessible(true); 782 783 // Notify JVMTI agents that VM initialization is complete - nop if no agents. 784 JvmtiExport::post_vm_initialized(); 785 786 JFR_ONLY(Jfr::on_create_vm_3();) 787 788 #if INCLUDE_MANAGEMENT 789 Management::initialize(THREAD); 790 791 if (HAS_PENDING_EXCEPTION) { 792 // management agent fails to start possibly due to 793 // configuration problem and is responsible for printing 794 // stack trace if appropriate. Simply exit VM. 795 vm_exit(1); 796 } 797 #endif // INCLUDE_MANAGEMENT 798 799 StatSampler::engage(); 800 if (CheckJNICalls) JniPeriodicChecker::engage(); 801 802 call_postVMInitHook(THREAD); 803 // The Java side of PostVMInitHook.run must deal with all 804 // exceptions and provide means of diagnosis. 805 if (HAS_PENDING_EXCEPTION) { 806 CLEAR_PENDING_EXCEPTION; 807 } 808 809 // Let WatcherThread run all registered periodic tasks now. 810 // NOTE: All PeriodicTasks should be registered by now. If they 811 // aren't, late joiners might appear to start slowly (we might 812 // take a while to process their first tick). 813 WatcherThread::run_all_tasks(); 814 815 create_vm_timer.end(); 816 #ifdef ASSERT 817 _vm_complete = true; 818 #endif 819 820 if (CDSConfig::is_dumping_static_archive()) { 821 MetaspaceShared::preload_and_dump(CHECK_JNI_ERR); 822 } 823 824 if (log_is_enabled(Info, perf, class, link)) { 825 LogStreamHandle(Info, perf, class, link) log; 826 log.print_cr("At VM initialization completion:"); 827 ClassLoader::print_counters(&log); 828 } 829 830 return JNI_OK; 831 } 832 833 // Threads::destroy_vm() is normally called from jni_DestroyJavaVM() when 834 // the program falls off the end of main(). Another VM exit path is through 835 // vm_exit(), when the program calls System.exit() to return a value, or when 836 // there is a serious error in VM. 837 // These two separate shutdown paths are not exactly the same, but they share 838 // Shutdown.shutdown() at Java level and before_exit() and VM_Exit op at VM level. 839 // 840 // Shutdown sequence: 841 // + Shutdown native memory tracking if it is on 842 // + Wait until we are the last non-daemon thread to execute 843 // <-- every thing is still working at this moment --> 844 // + Call java.lang.Shutdown.shutdown(), which will invoke Java level 845 // shutdown hooks 846 // + Call before_exit(), prepare for VM exit 847 // > run VM level shutdown hooks (they are registered through JVM_OnExit(), 848 // currently the only user of this mechanism is File.deleteOnExit()) 849 // > stop StatSampler, watcher thread, 850 // post thread end and vm death events to JVMTI, 851 // stop signal thread 852 // + Call JavaThread::exit(), it will: 853 // > release JNI handle blocks, remove stack guard pages 854 // > remove this thread from Threads list 855 // <-- no more Java code from this thread after this point --> 856 // + Stop VM thread, it will bring the remaining VM to a safepoint and stop 857 // the compiler threads at safepoint 858 // <-- do not use anything that could get blocked by Safepoint --> 859 // + Disable tracing at JNI/JVM barriers 860 // + Set _vm_exited flag for threads that are still running native code 861 // + Call exit_globals() 862 // > deletes tty 863 // > deletes PerfMemory resources 864 // + Delete this thread 865 // + Return to caller 866 867 void Threads::destroy_vm() { 868 JavaThread* thread = JavaThread::current(); 869 870 #ifdef ASSERT 871 _vm_complete = false; 872 #endif 873 // Wait until we are the last non-daemon thread to execute, or 874 // if we are a daemon then wait until the last non-daemon thread has 875 // executed. 876 bool daemon = java_lang_Thread::is_daemon(thread->threadObj()); 877 int expected = daemon ? 0 : 1; 878 { 879 MonitorLocker nu(Threads_lock); 880 while (Threads::number_of_non_daemon_threads() > expected) 881 // This wait should make safepoint checks, wait without a timeout. 882 nu.wait(0); 883 } 884 885 EventShutdown e; 886 if (e.should_commit()) { 887 e.set_reason("No remaining non-daemon Java threads"); 888 e.commit(); 889 } 890 891 // Hang forever on exit if we are reporting an error. 892 if (ShowMessageBoxOnError && VMError::is_error_reported()) { 893 os::infinite_sleep(); 894 } 895 os::wait_for_keypress_at_exit(); 896 897 // run Java level shutdown hooks 898 thread->invoke_shutdown_hooks(); 899 900 before_exit(thread); 901 902 thread->exit(true); 903 904 // We are no longer on the main thread list but could still be in a 905 // secondary list where another thread may try to interact with us. 906 // So wait until all such interactions are complete before we bring 907 // the VM to the termination safepoint. Normally this would be done 908 // using thread->smr_delete() below where we delete the thread, but 909 // we can't call that after the termination safepoint is active as 910 // we will deadlock on the Threads_lock. Once all interactions are 911 // complete it is safe to directly delete the thread at any time. 912 ThreadsSMRSupport::wait_until_not_protected(thread); 913 914 // Stop VM thread. 915 { 916 // 4945125 The vm thread comes to a safepoint during exit. 917 // GC vm_operations can get caught at the safepoint, and the 918 // heap is unparseable if they are caught. Grab the Heap_lock 919 // to prevent this. The GC vm_operations will not be able to 920 // queue until after the vm thread is dead. After this point, 921 // we'll never emerge out of the safepoint before the VM exits. 922 // Assert that the thread is terminated so that acquiring the 923 // Heap_lock doesn't cause the terminated thread to participate in 924 // the safepoint protocol. 925 926 assert(thread->is_terminated(), "must be terminated here"); 927 MutexLocker ml(Heap_lock); 928 929 VMThread::wait_for_vm_thread_exit(); 930 assert(SafepointSynchronize::is_at_safepoint(), "VM thread should exit at Safepoint"); 931 VMThread::destroy(); 932 } 933 934 // Now, all Java threads are gone except daemon threads. Daemon threads 935 // running Java code or in VM are stopped by the Safepoint. However, 936 // daemon threads executing native code are still running. But they 937 // will be stopped at native=>Java/VM barriers. Note that we can't 938 // simply kill or suspend them, as it is inherently deadlock-prone. 939 940 VM_Exit::set_vm_exited(); 941 942 // Clean up ideal graph printers after the VMThread has started 943 // the final safepoint which will block all the Compiler threads. 944 // Note that this Thread has already logically exited so the 945 // clean_up() function's use of a JavaThreadIteratorWithHandle 946 // would be a problem except set_vm_exited() has remembered the 947 // shutdown thread which is granted a policy exception. 948 #if defined(COMPILER2) && !defined(PRODUCT) 949 IdealGraphPrinter::clean_up(); 950 #endif 951 952 notify_vm_shutdown(); 953 954 // exit_globals() will delete tty 955 exit_globals(); 956 957 // Deleting the shutdown thread here is safe. See comment on 958 // wait_until_not_protected() above. 959 delete thread; 960 961 #if INCLUDE_JVMCI 962 if (JVMCICounterSize > 0) { 963 FREE_C_HEAP_ARRAY(jlong, JavaThread::_jvmci_old_thread_counters); 964 } 965 #endif 966 967 LogConfiguration::finalize(); 968 } 969 970 971 jboolean Threads::is_supported_jni_version_including_1_1(jint version) { 972 if (version == JNI_VERSION_1_1) return JNI_TRUE; 973 return is_supported_jni_version(version); 974 } 975 976 977 jboolean Threads::is_supported_jni_version(jint version) { 978 if (version == JNI_VERSION_1_2) return JNI_TRUE; 979 if (version == JNI_VERSION_1_4) return JNI_TRUE; 980 if (version == JNI_VERSION_1_6) return JNI_TRUE; 981 if (version == JNI_VERSION_1_8) return JNI_TRUE; 982 if (version == JNI_VERSION_9) return JNI_TRUE; 983 if (version == JNI_VERSION_10) return JNI_TRUE; 984 if (version == JNI_VERSION_19) return JNI_TRUE; 985 if (version == JNI_VERSION_20) return JNI_TRUE; 986 if (version == JNI_VERSION_21) return JNI_TRUE; 987 if (version == JNI_VERSION_24) return JNI_TRUE; 988 return JNI_FALSE; 989 } 990 991 void Threads::add(JavaThread* p, bool force_daemon) { 992 // The threads lock must be owned at this point 993 assert(Threads_lock->owned_by_self(), "must have threads lock"); 994 995 BarrierSet::barrier_set()->on_thread_attach(p); 996 997 // Once a JavaThread is added to the Threads list, smr_delete() has 998 // to be used to delete it. Otherwise we can just delete it directly. 999 p->set_on_thread_list(); 1000 1001 _number_of_threads++; 1002 oop threadObj = p->threadObj(); 1003 bool daemon = true; 1004 // Bootstrapping problem: threadObj can be null for initial 1005 // JavaThread (or for threads attached via JNI) 1006 if (!force_daemon && 1007 (threadObj == nullptr || !java_lang_Thread::is_daemon(threadObj))) { 1008 _number_of_non_daemon_threads++; 1009 daemon = false; 1010 } 1011 1012 ThreadService::add_thread(p, daemon); 1013 1014 // Maintain fast thread list 1015 ThreadsSMRSupport::add_thread(p); 1016 1017 // Increase the ObjectMonitor ceiling for the new thread. 1018 ObjectSynchronizer::inc_in_use_list_ceiling(); 1019 1020 // Possible GC point. 1021 Events::log(Thread::current(), "Thread added: " INTPTR_FORMAT, p2i(p)); 1022 1023 // Make new thread known to active EscapeBarrier 1024 EscapeBarrier::thread_added(p); 1025 } 1026 1027 void Threads::remove(JavaThread* p, bool is_daemon) { 1028 // Extra scope needed for Thread_lock, so we can check 1029 // that we do not remove thread without safepoint code notice 1030 { MonitorLocker ml(Threads_lock); 1031 1032 if (ThreadIdTable::is_initialized()) { 1033 // This cleanup must be done before the current thread's GC barrier 1034 // is detached since we need to touch the threadObj oop. 1035 jlong tid = SharedRuntime::get_java_tid(p); 1036 ThreadIdTable::remove_thread(tid); 1037 } 1038 1039 // BarrierSet state must be destroyed after the last thread transition 1040 // before the thread terminates. Thread transitions result in calls to 1041 // StackWatermarkSet::on_safepoint(), which performs GC processing, 1042 // requiring the GC state to be alive. 1043 BarrierSet::barrier_set()->on_thread_detach(p); 1044 if (p->is_exiting()) { 1045 // If we got here via JavaThread::exit(), then we remember that the 1046 // thread's GC barrier has been detached. We don't do this when we get 1047 // here from another path, e.g., cleanup_failed_attach_current_thread(). 1048 p->set_terminated(JavaThread::_thread_gc_barrier_detached); 1049 } 1050 1051 assert(ThreadsSMRSupport::get_java_thread_list()->includes(p), "p must be present"); 1052 1053 // Maintain fast thread list 1054 ThreadsSMRSupport::remove_thread(p); 1055 1056 _number_of_threads--; 1057 if (!is_daemon) { 1058 _number_of_non_daemon_threads--; 1059 1060 // If this is the last non-daemon thread then we need to do 1061 // a notify on the Threads_lock so a thread waiting 1062 // on destroy_vm will wake up. But that thread could be a daemon 1063 // or non-daemon, so we notify for both the 0 and 1 case. 1064 if (number_of_non_daemon_threads() <= 1) { 1065 ml.notify_all(); 1066 } 1067 } 1068 ThreadService::remove_thread(p, is_daemon); 1069 1070 // Make sure that safepoint code disregard this thread. This is needed since 1071 // the thread might mess around with locks after this point. This can cause it 1072 // to do callbacks into the safepoint code. However, the safepoint code is not aware 1073 // of this thread since it is removed from the queue. 1074 p->set_terminated(JavaThread::_thread_terminated); 1075 1076 // Notify threads waiting in EscapeBarriers 1077 EscapeBarrier::thread_removed(p); 1078 } // unlock Threads_lock 1079 1080 // Reduce the ObjectMonitor ceiling for the exiting thread. 1081 ObjectSynchronizer::dec_in_use_list_ceiling(); 1082 1083 // Since Events::log uses a lock, we grab it outside the Threads_lock 1084 Events::log(Thread::current(), "Thread exited: " INTPTR_FORMAT, p2i(p)); 1085 } 1086 1087 // Operations on the Threads list for GC. These are not explicitly locked, 1088 // but the garbage collector must provide a safe context for them to run. 1089 // In particular, these things should never be called when the Threads_lock 1090 // is held by some other thread. (Note: the Safepoint abstraction also 1091 // uses the Threads_lock to guarantee this property. It also makes sure that 1092 // all threads gets blocked when exiting or starting). 1093 1094 void Threads::oops_do(OopClosure* f, NMethodClosure* cf) { 1095 ALL_JAVA_THREADS(p) { 1096 p->oops_do(f, cf); 1097 } 1098 VMThread::vm_thread()->oops_do(f, cf); 1099 } 1100 1101 void Threads::change_thread_claim_token() { 1102 if (++_thread_claim_token == 0) { 1103 // On overflow of the token counter, there is a risk of future 1104 // collisions between a new global token value and a stale token 1105 // for a thread, because not all iterations visit all threads. 1106 // (Though it's pretty much a theoretical concern for non-trivial 1107 // token counter sizes.) To deal with the possibility, reset all 1108 // the thread tokens to zero on global token overflow. 1109 struct ResetClaims : public ThreadClosure { 1110 virtual void do_thread(Thread* t) { 1111 t->claim_threads_do(false, 0); 1112 } 1113 } reset_claims; 1114 Threads::threads_do(&reset_claims); 1115 // On overflow, update the global token to non-zero, to 1116 // avoid the special "never claimed" initial thread value. 1117 _thread_claim_token = 1; 1118 } 1119 } 1120 1121 #ifdef ASSERT 1122 static void assert_thread_claimed(const char* kind, Thread* t, uintx expected) { 1123 const uintx token = t->threads_do_token(); 1124 assert(token == expected, 1125 "%s " PTR_FORMAT " has incorrect value " UINTX_FORMAT " != " 1126 UINTX_FORMAT, kind, p2i(t), token, expected); 1127 } 1128 1129 void Threads::assert_all_threads_claimed() { 1130 ALL_JAVA_THREADS(p) { 1131 assert_thread_claimed("JavaThread", p, _thread_claim_token); 1132 } 1133 1134 struct NJTClaimedVerifierClosure : public ThreadClosure { 1135 uintx _thread_claim_token; 1136 1137 NJTClaimedVerifierClosure(uintx thread_claim_token) : ThreadClosure(), _thread_claim_token(thread_claim_token) { } 1138 1139 virtual void do_thread(Thread* thread) override { 1140 assert_thread_claimed("Non-JavaThread", VMThread::vm_thread(), _thread_claim_token); 1141 } 1142 } tc(_thread_claim_token); 1143 1144 non_java_threads_do(&tc); 1145 } 1146 #endif // ASSERT 1147 1148 class ParallelOopsDoThreadClosure : public ThreadClosure { 1149 private: 1150 OopClosure* _f; 1151 NMethodClosure* _cf; 1152 public: 1153 ParallelOopsDoThreadClosure(OopClosure* f, NMethodClosure* cf) : _f(f), _cf(cf) {} 1154 void do_thread(Thread* t) { 1155 t->oops_do(_f, _cf); 1156 } 1157 }; 1158 1159 void Threads::possibly_parallel_oops_do(bool is_par, OopClosure* f, NMethodClosure* cf) { 1160 ParallelOopsDoThreadClosure tc(f, cf); 1161 possibly_parallel_threads_do(is_par, &tc); 1162 } 1163 1164 void Threads::metadata_do(MetadataClosure* f) { 1165 ALL_JAVA_THREADS(p) { 1166 p->metadata_do(f); 1167 } 1168 } 1169 1170 class ThreadHandlesClosure : public ThreadClosure { 1171 void (*_f)(Metadata*); 1172 public: 1173 ThreadHandlesClosure(void f(Metadata*)) : _f(f) {} 1174 virtual void do_thread(Thread* thread) { 1175 thread->metadata_handles_do(_f); 1176 } 1177 }; 1178 1179 void Threads::metadata_handles_do(void f(Metadata*)) { 1180 // Only walk the Handles in Thread. 1181 ThreadHandlesClosure handles_closure(f); 1182 threads_do(&handles_closure); 1183 } 1184 1185 #if INCLUDE_JVMTI 1186 // Get Java threads that are waiting to enter or re-enter the specified monitor. 1187 // Java threads that are executing mounted virtual threads are not included. 1188 GrowableArray<JavaThread*>* Threads::get_pending_threads(ThreadsList * t_list, 1189 int count, 1190 address monitor) { 1191 assert(Thread::current()->is_VM_thread(), "Must be the VM thread"); 1192 GrowableArray<JavaThread*>* result = new GrowableArray<JavaThread*>(count); 1193 1194 int i = 0; 1195 for (JavaThread* p : *t_list) { 1196 if (!p->can_call_java()) continue; 1197 1198 oop thread_oop = JvmtiEnvBase::get_vthread_or_thread_oop(p); 1199 if (thread_oop->is_a(vmClasses::BaseVirtualThread_klass())) { 1200 continue; 1201 } 1202 // The first stage of async deflation does not affect any field 1203 // used by this comparison so the ObjectMonitor* is usable here. 1204 address pending = (address)p->current_pending_monitor(); 1205 address waiting = (address)p->current_waiting_monitor(); 1206 // do not include virtual threads to the list 1207 jint state = JvmtiEnvBase::get_thread_state(thread_oop, p); 1208 if (pending == monitor || (waiting == monitor && 1209 (state & JVMTI_THREAD_STATE_BLOCKED_ON_MONITOR_ENTER)) 1210 ) { // found a match 1211 if (i < count) result->append(p); // save the first count matches 1212 i++; 1213 } 1214 } 1215 1216 return result; 1217 } 1218 #endif // INCLUDE_JVMTI 1219 1220 JavaThread *Threads::owning_thread_from_monitor_owner(ThreadsList * t_list, 1221 address owner) { 1222 assert(LockingMode != LM_LIGHTWEIGHT, "Not with new lightweight locking"); 1223 // null owner means not locked so we can skip the search 1224 if (owner == nullptr) return nullptr; 1225 1226 for (JavaThread* p : *t_list) { 1227 // first, see if owner is the address of a Java thread 1228 if (owner == (address)p) return p; 1229 } 1230 1231 // Cannot assert on lack of success here since this function may be 1232 // used by code that is trying to report useful problem information 1233 // like deadlock detection. 1234 if (LockingMode == LM_MONITOR) return nullptr; 1235 1236 // If we didn't find a matching Java thread and we didn't force use of 1237 // heavyweight monitors, then the owner is the stack address of the 1238 // Lock Word in the owning Java thread's stack. 1239 // 1240 JavaThread* the_owner = nullptr; 1241 for (JavaThread* q : *t_list) { 1242 if (q->is_lock_owned(owner)) { 1243 the_owner = q; 1244 break; 1245 } 1246 } 1247 1248 // cannot assert on lack of success here; see above comment 1249 return the_owner; 1250 } 1251 1252 JavaThread* Threads::owning_thread_from_object(ThreadsList * t_list, oop obj) { 1253 assert(LockingMode == LM_LIGHTWEIGHT, "Only with new lightweight locking"); 1254 for (JavaThread* q : *t_list) { 1255 // Need to start processing before accessing oops in the thread. 1256 StackWatermark* watermark = StackWatermarkSet::get(q, StackWatermarkKind::gc); 1257 if (watermark != nullptr) { 1258 watermark->start_processing(); 1259 } 1260 1261 if (q->lock_stack().contains(obj)) { 1262 return q; 1263 } 1264 } 1265 return nullptr; 1266 } 1267 1268 JavaThread* Threads::owning_thread_from_monitor(ThreadsList* t_list, ObjectMonitor* monitor) { 1269 if (LockingMode == LM_LIGHTWEIGHT) { 1270 if (monitor->is_owner_anonymous()) { 1271 return owning_thread_from_object(t_list, monitor->object()); 1272 } else { 1273 Thread* owner = reinterpret_cast<Thread*>(monitor->owner()); 1274 assert(owner == nullptr || owner->is_Java_thread(), "only JavaThreads own monitors"); 1275 return reinterpret_cast<JavaThread*>(owner); 1276 } 1277 } else { 1278 address owner = (address)monitor->owner(); 1279 return owning_thread_from_monitor_owner(t_list, owner); 1280 } 1281 } 1282 1283 class PrintOnClosure : public ThreadClosure { 1284 private: 1285 outputStream* _st; 1286 1287 public: 1288 PrintOnClosure(outputStream* st) : 1289 _st(st) {} 1290 1291 virtual void do_thread(Thread* thread) { 1292 if (thread != nullptr) { 1293 thread->print_on(_st); 1294 _st->cr(); 1295 } 1296 } 1297 }; 1298 1299 // Threads::print_on() is called at safepoint by VM_PrintThreads operation. 1300 void Threads::print_on(outputStream* st, bool print_stacks, 1301 bool internal_format, bool print_concurrent_locks, 1302 bool print_extended_info) { 1303 char buf[32]; 1304 st->print_raw_cr(os::local_time_string(buf, sizeof(buf))); 1305 1306 st->print_cr("Full thread dump %s (%s %s):", 1307 VM_Version::vm_name(), 1308 VM_Version::vm_release(), 1309 VM_Version::vm_info_string()); 1310 st->cr(); 1311 1312 #if INCLUDE_SERVICES 1313 // Dump concurrent locks 1314 ConcurrentLocksDump concurrent_locks; 1315 if (print_concurrent_locks) { 1316 concurrent_locks.dump_at_safepoint(); 1317 } 1318 #endif // INCLUDE_SERVICES 1319 1320 ThreadsSMRSupport::print_info_on(st); 1321 st->cr(); 1322 1323 ALL_JAVA_THREADS(p) { 1324 ResourceMark rm; 1325 p->print_on(st, print_extended_info); 1326 if (print_stacks) { 1327 if (internal_format) { 1328 p->trace_stack(); 1329 } else { 1330 p->print_stack_on(st); 1331 const oop thread_oop = p->threadObj(); 1332 if (thread_oop != nullptr) { 1333 if (p->is_vthread_mounted()) { 1334 const oop vt = p->vthread(); 1335 assert(vt != nullptr, "vthread should not be null when vthread is mounted"); 1336 // JavaThread._vthread can refer to the carrier thread. Print only if _vthread refers to a virtual thread. 1337 if (vt != thread_oop) { 1338 st->print_cr(" Mounted virtual thread #" INT64_FORMAT, (int64_t)java_lang_Thread::thread_id(vt)); 1339 p->print_vthread_stack_on(st); 1340 } 1341 } 1342 } 1343 } 1344 } 1345 st->cr(); 1346 #if INCLUDE_SERVICES 1347 if (print_concurrent_locks) { 1348 concurrent_locks.print_locks_on(p, st); 1349 } 1350 #endif // INCLUDE_SERVICES 1351 } 1352 1353 PrintOnClosure cl(st); 1354 non_java_threads_do(&cl); 1355 1356 st->flush(); 1357 } 1358 1359 void Threads::print_on_error(Thread* this_thread, outputStream* st, Thread* current, char* buf, 1360 int buflen, bool* found_current) { 1361 if (this_thread != nullptr) { 1362 bool is_current = (current == this_thread); 1363 *found_current = *found_current || is_current; 1364 st->print("%s", is_current ? "=>" : " "); 1365 1366 st->print(PTR_FORMAT, p2i(this_thread)); 1367 st->print(" "); 1368 this_thread->print_on_error(st, buf, buflen); 1369 st->cr(); 1370 } 1371 } 1372 1373 class PrintOnErrorClosure : public ThreadClosure { 1374 outputStream* _st; 1375 Thread* _current; 1376 char* _buf; 1377 int _buflen; 1378 bool* _found_current; 1379 unsigned _num_printed; 1380 public: 1381 PrintOnErrorClosure(outputStream* st, Thread* current, char* buf, 1382 int buflen, bool* found_current) : 1383 _st(st), _current(current), _buf(buf), _buflen(buflen), _found_current(found_current), 1384 _num_printed(0) {} 1385 1386 virtual void do_thread(Thread* thread) { 1387 _num_printed++; 1388 Threads::print_on_error(thread, _st, _current, _buf, _buflen, _found_current); 1389 } 1390 1391 unsigned num_printed() const { return _num_printed; } 1392 }; 1393 1394 // Threads::print_on_error() is called by fatal error handler. It's possible 1395 // that VM is not at safepoint and/or current thread is inside signal handler. 1396 // Don't print stack trace, as the stack may not be walkable. Don't allocate 1397 // memory (even in resource area), it might deadlock the error handler. 1398 void Threads::print_on_error(outputStream* st, Thread* current, char* buf, 1399 int buflen) { 1400 ThreadsSMRSupport::print_info_on(st); 1401 st->cr(); 1402 1403 bool found_current = false; 1404 st->print_cr("Java Threads: ( => current thread )"); 1405 unsigned num_java = 0; 1406 ALL_JAVA_THREADS(thread) { 1407 print_on_error(thread, st, current, buf, buflen, &found_current); 1408 num_java++; 1409 } 1410 st->print_cr("Total: %u", num_java); 1411 st->cr(); 1412 1413 st->print_cr("Other Threads:"); 1414 unsigned num_other = ((VMThread::vm_thread() != nullptr) ? 1 : 0) + 1415 ((WatcherThread::watcher_thread() != nullptr) ? 1 : 0) + 1416 ((AsyncLogWriter::instance() != nullptr) ? 1 : 0); 1417 print_on_error(VMThread::vm_thread(), st, current, buf, buflen, &found_current); 1418 print_on_error(WatcherThread::watcher_thread(), st, current, buf, buflen, &found_current); 1419 print_on_error(AsyncLogWriter::instance(), st, current, buf, buflen, &found_current); 1420 1421 if (Universe::heap() != nullptr) { 1422 PrintOnErrorClosure print_closure(st, current, buf, buflen, &found_current); 1423 Universe::heap()->gc_threads_do(&print_closure); 1424 num_other += print_closure.num_printed(); 1425 } 1426 1427 if (!found_current) { 1428 st->cr(); 1429 st->print("=>" PTR_FORMAT " (exited) ", p2i(current)); 1430 current->print_on_error(st, buf, buflen); 1431 num_other++; 1432 st->cr(); 1433 } 1434 st->print_cr("Total: %u", num_other); 1435 st->cr(); 1436 1437 st->print_cr("Threads with active compile tasks:"); 1438 unsigned num = print_threads_compiling(st, buf, buflen); 1439 st->print_cr("Total: %u", num); 1440 } 1441 1442 unsigned Threads::print_threads_compiling(outputStream* st, char* buf, int buflen, bool short_form) { 1443 unsigned num = 0; 1444 ALL_JAVA_THREADS(thread) { 1445 if (thread->is_Compiler_thread()) { 1446 CompilerThread* ct = (CompilerThread*) thread; 1447 1448 // Keep task in local variable for null check. 1449 // ct->_task might be set to null by concurring compiler thread 1450 // because it completed the compilation. The task is never freed, 1451 // though, just returned to a free list. 1452 CompileTask* task = ct->task(); 1453 if (task != nullptr) { 1454 thread->print_name_on_error(st, buf, buflen); 1455 st->print(" "); 1456 task->print(st, nullptr, short_form, true); 1457 num++; 1458 } 1459 } 1460 } 1461 return num; 1462 } 1463 1464 void Threads::verify() { 1465 ALL_JAVA_THREADS(p) { 1466 p->verify(); 1467 } 1468 VMThread* thread = VMThread::vm_thread(); 1469 if (thread != nullptr) thread->verify(); 1470 }