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 JFR_ONLY(assert(JFR_JVM_THREAD_ID(thread) == static_cast<traceid>(java_lang_Thread::thread_id(thread_oop())), 170 "initial tid mismatch");) 171 172 // Set thread status to running since main thread has 173 // been started and running. 174 java_lang_Thread::set_thread_status(thread_oop(), 175 JavaThreadStatus::RUNNABLE); 176 } 177 178 // Extract version and vendor specific information from 179 // java.lang.VersionProps fields. 180 // Returned char* is allocated in the thread's resource area 181 // so must be copied for permanency. 182 static const char* get_java_version_info(InstanceKlass* ik, 183 Symbol* field_name) { 184 fieldDescriptor fd; 185 bool found = ik != nullptr && 186 ik->find_local_field(field_name, 187 vmSymbols::string_signature(), &fd); 188 if (found) { 189 oop name_oop = ik->java_mirror()->obj_field(fd.offset()); 190 if (name_oop == nullptr) { 191 return nullptr; 192 } 193 const char* name = java_lang_String::as_utf8_string(name_oop); 194 return name; 195 } else { 196 return nullptr; 197 } 198 } 199 200 // ======= Threads ======== 201 202 // The Threads class links together all active threads, and provides 203 // operations over all threads. It is protected by the Threads_lock, 204 // which is also used in other global contexts like safepointing. 205 // ThreadsListHandles are used to safely perform operations on one 206 // or more threads without the risk of the thread exiting during the 207 // operation. 208 // 209 // Note: The Threads_lock is currently more widely used than we 210 // would like. We are actively migrating Threads_lock uses to other 211 // mechanisms in order to reduce Threads_lock contention. 212 213 int Threads::_number_of_threads = 0; 214 int Threads::_number_of_non_daemon_threads = 0; 215 int Threads::_return_code = 0; 216 uintx Threads::_thread_claim_token = 1; // Never zero. 217 218 #ifdef ASSERT 219 bool Threads::_vm_complete = false; 220 #endif 221 222 // General purpose hook into Java code, run once when the VM is initialized. 223 // The Java library method itself may be changed independently from the VM. 224 static void call_postVMInitHook(TRAPS) { 225 Klass* klass = SystemDictionary::resolve_or_null(vmSymbols::jdk_internal_vm_PostVMInitHook(), THREAD); 226 if (klass != nullptr) { 227 JavaValue result(T_VOID); 228 JavaCalls::call_static(&result, klass, vmSymbols::run_method_name(), 229 vmSymbols::void_method_signature(), 230 CHECK); 231 } 232 } 233 234 // All NonJavaThreads (i.e., every non-JavaThread in the system). 235 void Threads::non_java_threads_do(ThreadClosure* tc) { 236 NoSafepointVerifier nsv; 237 for (NonJavaThread::Iterator njti; !njti.end(); njti.step()) { 238 tc->do_thread(njti.current()); 239 } 240 } 241 242 // All JavaThreads 243 #define ALL_JAVA_THREADS(X) \ 244 for (JavaThread* X : *ThreadsSMRSupport::get_java_thread_list()) 245 246 // All JavaThreads 247 void Threads::java_threads_do(ThreadClosure* tc) { 248 assert_locked_or_safepoint(Threads_lock); 249 // ALL_JAVA_THREADS iterates through all JavaThreads. 250 ALL_JAVA_THREADS(p) { 251 tc->do_thread(p); 252 } 253 } 254 255 // All JavaThreads + all non-JavaThreads (i.e., every thread in the system). 256 void Threads::threads_do(ThreadClosure* tc) { 257 assert_locked_or_safepoint(Threads_lock); 258 java_threads_do(tc); 259 non_java_threads_do(tc); 260 } 261 262 void Threads::possibly_parallel_threads_do(bool is_par, ThreadClosure* tc) { 263 assert_at_safepoint(); 264 265 uintx claim_token = Threads::thread_claim_token(); 266 ALL_JAVA_THREADS(p) { 267 if (p->claim_threads_do(is_par, claim_token)) { 268 tc->do_thread(p); 269 } 270 } 271 for (NonJavaThread::Iterator njti; !njti.end(); njti.step()) { 272 Thread* current = njti.current(); 273 if (current->claim_threads_do(is_par, claim_token)) { 274 tc->do_thread(current); 275 } 276 } 277 } 278 279 // The system initialization in the library has three phases. 280 // 281 // Phase 1: java.lang.System class initialization 282 // java.lang.System is a primordial class loaded and initialized 283 // by the VM early during startup. java.lang.System.<clinit> 284 // only does registerNatives and keeps the rest of the class 285 // initialization work later until thread initialization completes. 286 // 287 // System.initPhase1 initializes the system properties, the static 288 // fields in, out, and err. Set up java signal handlers, OS-specific 289 // system settings, and thread group of the main thread. 290 static void call_initPhase1(TRAPS) { 291 Klass* klass = vmClasses::System_klass(); 292 JavaValue result(T_VOID); 293 JavaCalls::call_static(&result, klass, vmSymbols::initPhase1_name(), 294 vmSymbols::void_method_signature(), CHECK); 295 } 296 297 // Phase 2. Module system initialization 298 // This will initialize the module system. Only java.base classes 299 // can be loaded until phase 2 completes. 300 // 301 // Call System.initPhase2 after the compiler initialization and jsr292 302 // classes get initialized because module initialization runs a lot of java 303 // code, that for performance reasons, should be compiled. Also, this will 304 // enable the startup code to use lambda and other language features in this 305 // phase and onward. 306 // 307 // After phase 2, The VM will begin search classes from -Xbootclasspath/a. 308 static void call_initPhase2(TRAPS) { 309 TraceTime timer("Initialize module system", TRACETIME_LOG(Info, startuptime)); 310 311 Klass* klass = vmClasses::System_klass(); 312 313 JavaValue result(T_INT); 314 JavaCallArguments args; 315 args.push_int(DisplayVMOutputToStderr); 316 args.push_int(log_is_enabled(Debug, init)); // print stack trace if exception thrown 317 JavaCalls::call_static(&result, klass, vmSymbols::initPhase2_name(), 318 vmSymbols::boolean_boolean_int_signature(), &args, CHECK); 319 if (result.get_jint() != JNI_OK) { 320 vm_exit_during_initialization(); // no message or exception 321 } 322 323 universe_post_module_init(); 324 } 325 326 // Phase 3. final setup - set security manager, system class loader and TCCL 327 // 328 // This will instantiate and set the security manager, set the system class 329 // loader as well as the thread context class loader. The security manager 330 // and system class loader may be a custom class loaded from -Xbootclasspath/a, 331 // other modules or the application's classpath. 332 static void call_initPhase3(TRAPS) { 333 Klass* klass = vmClasses::System_klass(); 334 JavaValue result(T_VOID); 335 JavaCalls::call_static(&result, klass, vmSymbols::initPhase3_name(), 336 vmSymbols::void_method_signature(), CHECK); 337 } 338 339 void Threads::initialize_java_lang_classes(JavaThread* main_thread, TRAPS) { 340 TraceTime timer("Initialize java.lang classes", TRACETIME_LOG(Info, startuptime)); 341 342 initialize_class(vmSymbols::java_lang_String(), CHECK); 343 344 // Inject CompactStrings value after the static initializers for String ran. 345 java_lang_String::set_compact_strings(CompactStrings); 346 347 // Initialize java_lang.System (needed before creating the thread) 348 initialize_class(vmSymbols::java_lang_System(), CHECK); 349 // The VM creates & returns objects of this class. Make sure it's initialized. 350 initialize_class(vmSymbols::java_lang_Class(), CHECK); 351 initialize_class(vmSymbols::java_lang_ThreadGroup(), CHECK); 352 Handle thread_group = create_initial_thread_group(CHECK); 353 Universe::set_main_thread_group(thread_group()); 354 initialize_class(vmSymbols::java_lang_Thread(), CHECK); 355 create_initial_thread(thread_group, main_thread, CHECK); 356 357 // The VM creates objects of this class. 358 initialize_class(vmSymbols::java_lang_Module(), CHECK); 359 360 #ifdef ASSERT 361 InstanceKlass *k = vmClasses::UnsafeConstants_klass(); 362 assert(k->is_not_initialized(), "UnsafeConstants should not already be initialized"); 363 #endif 364 365 // initialize the hardware-specific constants needed by Unsafe 366 initialize_class(vmSymbols::jdk_internal_misc_UnsafeConstants(), CHECK); 367 jdk_internal_misc_UnsafeConstants::set_unsafe_constants(); 368 369 // The VM preresolves methods to these classes. Make sure that they get initialized 370 initialize_class(vmSymbols::java_lang_reflect_Method(), CHECK); 371 initialize_class(vmSymbols::java_lang_ref_Finalizer(), CHECK); 372 373 // Phase 1 of the system initialization in the library, java.lang.System class initialization 374 call_initPhase1(CHECK); 375 376 // Get the Java runtime name, version, and vendor info after java.lang.System is initialized. 377 // Some values are actually configure-time constants but some can be set via the jlink tool and 378 // so must be read dynamically. We treat them all the same. 379 InstanceKlass* ik = SystemDictionary::find_instance_klass(THREAD, vmSymbols::java_lang_VersionProps(), 380 Handle(), Handle()); 381 { 382 ResourceMark rm(main_thread); 383 JDK_Version::set_java_version(get_java_version_info(ik, vmSymbols::java_version_name())); 384 385 JDK_Version::set_runtime_name(get_java_version_info(ik, vmSymbols::java_runtime_name_name())); 386 387 JDK_Version::set_runtime_version(get_java_version_info(ik, vmSymbols::java_runtime_version_name())); 388 389 JDK_Version::set_runtime_vendor_version(get_java_version_info(ik, vmSymbols::java_runtime_vendor_version_name())); 390 391 JDK_Version::set_runtime_vendor_vm_bug_url(get_java_version_info(ik, vmSymbols::java_runtime_vendor_vm_bug_url_name())); 392 } 393 394 // an instance of OutOfMemory exception has been allocated earlier 395 initialize_class(vmSymbols::java_lang_OutOfMemoryError(), CHECK); 396 initialize_class(vmSymbols::java_lang_NullPointerException(), CHECK); 397 initialize_class(vmSymbols::java_lang_ClassCastException(), CHECK); 398 initialize_class(vmSymbols::java_lang_ArrayStoreException(), CHECK); 399 initialize_class(vmSymbols::java_lang_ArithmeticException(), CHECK); 400 initialize_class(vmSymbols::java_lang_ArrayIndexOutOfBoundsException(), CHECK); 401 initialize_class(vmSymbols::java_lang_StackOverflowError(), CHECK); 402 initialize_class(vmSymbols::java_lang_IllegalMonitorStateException(), CHECK); 403 initialize_class(vmSymbols::java_lang_IllegalArgumentException(), CHECK); 404 } 405 406 void Threads::initialize_jsr292_core_classes(TRAPS) { 407 TraceTime timer("Initialize java.lang.invoke classes", TRACETIME_LOG(Info, startuptime)); 408 409 initialize_class(vmSymbols::java_lang_invoke_MethodHandle(), CHECK); 410 initialize_class(vmSymbols::java_lang_invoke_ResolvedMethodName(), CHECK); 411 initialize_class(vmSymbols::java_lang_invoke_MemberName(), CHECK); 412 initialize_class(vmSymbols::java_lang_invoke_MethodHandleNatives(), CHECK); 413 } 414 415 jint Threads::create_vm(JavaVMInitArgs* args, bool* canTryAgain) { 416 extern void JDK_Version_init(); 417 418 // Preinitialize version info. 419 VM_Version::early_initialize(); 420 421 // Check version 422 if (!is_supported_jni_version(args->version)) return JNI_EVERSION; 423 424 // Initialize library-based TLS 425 ThreadLocalStorage::init(); 426 427 // Initialize the output stream module 428 ostream_init(); 429 430 // Process java launcher properties. 431 Arguments::process_sun_java_launcher_properties(args); 432 433 // Initialize the os module 434 os::init(); 435 436 MACOS_AARCH64_ONLY(os::current_thread_enable_wx(WXWrite)); 437 438 // Record VM creation timing statistics 439 TraceVmCreationTime create_vm_timer; 440 create_vm_timer.start(); 441 442 // Initialize system properties. 443 Arguments::init_system_properties(); 444 445 // So that JDK version can be used as a discriminator when parsing arguments 446 JDK_Version_init(); 447 448 // Update/Initialize System properties after JDK version number is known 449 Arguments::init_version_specific_system_properties(); 450 451 // Make sure to initialize log configuration *before* parsing arguments 452 LogConfiguration::initialize(create_vm_timer.begin_time()); 453 454 // Parse arguments 455 // Note: this internally calls os::init_container_support() 456 jint parse_result = Arguments::parse(args); 457 if (parse_result != JNI_OK) return parse_result; 458 459 // Initialize NMT right after argument parsing to keep the pre-NMT-init window small. 460 MemTracker::initialize(); 461 462 os::init_before_ergo(); 463 464 jint ergo_result = Arguments::apply_ergo(); 465 if (ergo_result != JNI_OK) return ergo_result; 466 467 // Final check of all ranges after ergonomics which may change values. 468 if (!JVMFlagLimit::check_all_ranges()) { 469 return JNI_EINVAL; 470 } 471 472 // Final check of all 'AfterErgo' constraints after ergonomics which may change values. 473 bool constraint_result = JVMFlagLimit::check_all_constraints(JVMFlagConstraintPhase::AfterErgo); 474 if (!constraint_result) { 475 return JNI_EINVAL; 476 } 477 478 if (PauseAtStartup) { 479 os::pause(); 480 } 481 482 HOTSPOT_VM_INIT_BEGIN(); 483 484 // Timing (must come after argument parsing) 485 TraceTime timer("Create VM", TRACETIME_LOG(Info, startuptime)); 486 487 // Initialize the os module after parsing the args 488 jint os_init_2_result = os::init_2(); 489 if (os_init_2_result != JNI_OK) return os_init_2_result; 490 491 #ifdef CAN_SHOW_REGISTERS_ON_ASSERT 492 // Initialize assert poison page mechanism. 493 if (ShowRegistersOnAssert) { 494 initialize_assert_poison(); 495 } 496 #endif // CAN_SHOW_REGISTERS_ON_ASSERT 497 498 SafepointMechanism::initialize(); 499 500 jint adjust_after_os_result = Arguments::adjust_after_os(); 501 if (adjust_after_os_result != JNI_OK) return adjust_after_os_result; 502 503 // Initialize output stream logging 504 ostream_init_log(); 505 506 // Launch -agentlib/-agentpath and converted -Xrun agents 507 JvmtiAgentList::load_agents(); 508 509 // Initialize Threads state 510 _number_of_threads = 0; 511 _number_of_non_daemon_threads = 0; 512 513 // Initialize global data structures and create system classes in heap 514 vm_init_globals(); 515 516 #if INCLUDE_JVMCI 517 if (JVMCICounterSize > 0) { 518 JavaThread::_jvmci_old_thread_counters = NEW_C_HEAP_ARRAY(jlong, JVMCICounterSize, mtJVMCI); 519 memset(JavaThread::_jvmci_old_thread_counters, 0, sizeof(jlong) * JVMCICounterSize); 520 } else { 521 JavaThread::_jvmci_old_thread_counters = nullptr; 522 } 523 #endif // INCLUDE_JVMCI 524 525 // Initialize OopStorage for threadObj 526 JavaThread::_thread_oop_storage = OopStorageSet::create_strong("Thread OopStorage", mtThread); 527 528 // Attach the main thread to this os thread 529 JavaThread* main_thread = new JavaThread(); 530 main_thread->set_thread_state(_thread_in_vm); 531 main_thread->initialize_thread_current(); 532 // must do this before set_active_handles 533 main_thread->record_stack_base_and_size(); 534 main_thread->register_thread_stack_with_NMT(); 535 main_thread->set_active_handles(JNIHandleBlock::allocate_block()); 536 MACOS_AARCH64_ONLY(main_thread->init_wx()); 537 538 if (!Thread::set_as_starting_thread(main_thread)) { 539 vm_shutdown_during_initialization( 540 "Failed necessary internal allocation. Out of swap space"); 541 main_thread->smr_delete(); 542 *canTryAgain = false; // don't let caller call JNI_CreateJavaVM again 543 return JNI_ENOMEM; 544 } 545 546 JFR_ONLY(Jfr::initialize_main_thread(main_thread);) 547 548 // Enable guard page *after* os::create_main_thread(), otherwise it would 549 // crash Linux VM, see notes in os_linux.cpp. 550 main_thread->stack_overflow_state()->create_stack_guard_pages(); 551 552 // Initialize Java-Level synchronization subsystem 553 ObjectMonitor::Initialize(); 554 ObjectSynchronizer::initialize(); 555 556 // Initialize global modules 557 jint status = init_globals(); 558 if (status != JNI_OK) { 559 main_thread->smr_delete(); 560 *canTryAgain = false; // don't let caller call JNI_CreateJavaVM again 561 return status; 562 } 563 564 // Create WatcherThread as soon as we can since we need it in case 565 // of hangs during error reporting. 566 WatcherThread::start(); 567 568 // Add main_thread to threads list to finish barrier setup with 569 // on_thread_attach. Should be before starting to build Java objects in 570 // init_globals2, which invokes barriers. 571 { 572 MutexLocker mu(Threads_lock); 573 Threads::add(main_thread); 574 } 575 576 status = init_globals2(); 577 if (status != JNI_OK) { 578 Threads::remove(main_thread, false); 579 // It is possible that we managed to fully initialize Universe but have then 580 // failed by throwing an exception. In that case our caller JNI_CreateJavaVM 581 // will want to report it, so we can't delete the main thread. 582 if (!main_thread->has_pending_exception()) { 583 main_thread->smr_delete(); 584 } 585 *canTryAgain = false; // don't let caller call JNI_CreateJavaVM again 586 return status; 587 } 588 589 JFR_ONLY(Jfr::on_create_vm_1();) 590 591 // Should be done after the heap is fully created 592 main_thread->cache_global_variables(); 593 594 // Any JVMTI raw monitors entered in onload will transition into 595 // real raw monitor. VM is setup enough here for raw monitor enter. 596 JvmtiExport::transition_pending_onload_raw_monitors(); 597 598 // Create the VMThread 599 { TraceTime timer("Start VMThread", TRACETIME_LOG(Info, startuptime)); 600 601 VMThread::create(); 602 VMThread* vmthread = VMThread::vm_thread(); 603 604 if (!os::create_thread(vmthread, os::vm_thread)) { 605 vm_exit_during_initialization("Cannot create VM thread. " 606 "Out of system resources."); 607 } 608 609 // Wait for the VM thread to become ready, and VMThread::run to initialize 610 // Monitors can have spurious returns, must always check another state flag 611 { 612 MonitorLocker ml(Notify_lock); 613 os::start_thread(vmthread); 614 while (!vmthread->is_running()) { 615 ml.wait(); 616 } 617 } 618 } 619 620 assert(Universe::is_fully_initialized(), "not initialized"); 621 if (VerifyDuringStartup) { 622 // Make sure we're starting with a clean slate. 623 VM_Verify verify_op; 624 VMThread::execute(&verify_op); 625 } 626 627 // We need this to update the java.vm.info property in case any flags used 628 // to initially define it have been changed. This is needed for both CDS 629 // since UseSharedSpaces may be changed after java.vm.info 630 // is initially computed. See Abstract_VM_Version::vm_info_string(). 631 // This update must happen before we initialize the java classes, but 632 // after any initialization logic that might modify the flags. 633 Arguments::update_vm_info_property(VM_Version::vm_info_string()); 634 635 JavaThread* THREAD = JavaThread::current(); // For exception macros. 636 HandleMark hm(THREAD); 637 638 // Always call even when there are not JVMTI environments yet, since environments 639 // may be attached late and JVMTI must track phases of VM execution 640 JvmtiExport::enter_early_start_phase(); 641 642 // Notify JVMTI agents that VM has started (JNI is up) - nop if no agents. 643 JvmtiExport::post_early_vm_start(); 644 645 // Launch -Xrun agents early if EagerXrunInit is set 646 if (EagerXrunInit) { 647 JvmtiAgentList::load_xrun_agents(); 648 } 649 650 initialize_java_lang_classes(main_thread, CHECK_JNI_ERR); 651 652 quicken_jni_functions(); 653 654 // No more stub generation allowed after that point. 655 StubCodeDesc::freeze(); 656 657 // Set flag that basic initialization has completed. Used by exceptions and various 658 // debug stuff, that does not work until all basic classes have been initialized. 659 set_init_completed(); 660 661 LogConfiguration::post_initialize(); 662 Metaspace::post_initialize(); 663 MutexLockerImpl::post_initialize(); 664 665 HOTSPOT_VM_INIT_END(); 666 667 // record VM initialization completion time 668 #if INCLUDE_MANAGEMENT 669 Management::record_vm_init_completed(); 670 #endif // INCLUDE_MANAGEMENT 671 672 log_info(os)("Initialized VM with process ID %d", os::current_process_id()); 673 674 if (!FLAG_IS_DEFAULT(CreateCoredumpOnCrash) && CreateCoredumpOnCrash) { 675 char buffer[2*JVM_MAXPATHLEN]; 676 os::check_core_dump_prerequisites(buffer, sizeof(buffer), true); 677 } 678 679 // Signal Dispatcher needs to be started before VMInit event is posted 680 os::initialize_jdk_signal_support(CHECK_JNI_ERR); 681 682 // Start Attach Listener if +StartAttachListener or it can't be started lazily 683 if (!DisableAttachMechanism) { 684 AttachListener::vm_start(); 685 if (StartAttachListener || AttachListener::init_at_startup()) { 686 AttachListener::init(); 687 } 688 } 689 690 // Launch -Xrun agents if EagerXrunInit is not set. 691 if (!EagerXrunInit) { 692 JvmtiAgentList::load_xrun_agents(); 693 } 694 695 Arena::start_chunk_pool_cleaner_task(); 696 697 // Start the service thread 698 // The service thread enqueues JVMTI deferred events and does various hashtable 699 // and other cleanups. Needs to start before the compilers start posting events. 700 ServiceThread::initialize(); 701 702 // Start the monitor deflation thread: 703 MonitorDeflationThread::initialize(); 704 705 // initialize compiler(s) 706 #if defined(COMPILER1) || COMPILER2_OR_JVMCI 707 bool init_compilation = true; 708 #if INCLUDE_JVMCI 709 bool force_JVMCI_initialization = false; 710 if (EnableJVMCI) { 711 // Initialize JVMCI eagerly when it is explicitly requested. 712 // Or when JVMCILibDumpJNIConfig or JVMCIPrintProperties is enabled. 713 force_JVMCI_initialization = EagerJVMCI || JVMCIPrintProperties || JVMCILibDumpJNIConfig; 714 if (!force_JVMCI_initialization && UseJVMCICompiler && !UseJVMCINativeLibrary && (!UseInterpreter || !BackgroundCompilation)) { 715 // Force initialization of jarjvmci otherwise requests for blocking 716 // compilations will not actually block until jarjvmci is initialized. 717 force_JVMCI_initialization = true; 718 } 719 if (JVMCIPrintProperties || JVMCILibDumpJNIConfig) { 720 // Both JVMCILibDumpJNIConfig and JVMCIPrintProperties exit the VM 721 // so compilation should be disabled. This prevents dumping or 722 // printing from happening more than once. 723 init_compilation = false; 724 } 725 } 726 #endif 727 if (init_compilation) { 728 CompileBroker::compilation_init(CHECK_JNI_ERR); 729 } 730 #endif 731 732 // Start string deduplication thread if requested. 733 if (StringDedup::is_enabled()) { 734 StringDedup::start(); 735 } 736 737 // Pre-initialize some JSR292 core classes to avoid deadlock during class loading. 738 // It is done after compilers are initialized, because otherwise compilations of 739 // signature polymorphic MH intrinsics can be missed 740 // (see SystemDictionary::find_method_handle_intrinsic). 741 initialize_jsr292_core_classes(CHECK_JNI_ERR); 742 743 // This will initialize the module system. Only java.base classes can be 744 // loaded until phase 2 completes 745 call_initPhase2(CHECK_JNI_ERR); 746 747 JFR_ONLY(Jfr::on_create_vm_2();) 748 749 // Always call even when there are not JVMTI environments yet, since environments 750 // may be attached late and JVMTI must track phases of VM execution 751 JvmtiExport::enter_start_phase(); 752 753 // Notify JVMTI agents that VM has started (JNI is up) - nop if no agents. 754 JvmtiExport::post_vm_start(); 755 756 // Final system initialization including security manager and system class loader 757 call_initPhase3(CHECK_JNI_ERR); 758 759 // cache the system and platform class loaders 760 SystemDictionary::compute_java_loaders(CHECK_JNI_ERR); 761 762 if (Continuations::enabled()) { 763 // Initialize Continuation class now so that failure to create enterSpecial/doYield 764 // special nmethods due to limited CodeCache size can be treated as a fatal error at 765 // startup with the proper message that CodeCache size is too small. 766 initialize_class(vmSymbols::jdk_internal_vm_Continuation(), CHECK_JNI_ERR); 767 } 768 769 #if INCLUDE_CDS 770 // capture the module path info from the ModuleEntryTable 771 ClassLoader::initialize_module_path(THREAD); 772 if (HAS_PENDING_EXCEPTION) { 773 java_lang_Throwable::print(PENDING_EXCEPTION, tty); 774 vm_exit_during_initialization("ClassLoader::initialize_module_path() failed unexpectedly"); 775 } 776 #endif 777 778 #if INCLUDE_JVMCI 779 if (force_JVMCI_initialization) { 780 JVMCI::initialize_compiler(CHECK_JNI_ERR); 781 } 782 #endif 783 784 if (NativeHeapTrimmer::enabled()) { 785 NativeHeapTrimmer::initialize(); 786 } 787 788 // Always call even when there are not JVMTI environments yet, since environments 789 // may be attached late and JVMTI must track phases of VM execution 790 JvmtiExport::enter_live_phase(); 791 792 // Make perfmemory accessible 793 PerfMemory::set_accessible(true); 794 795 // Notify JVMTI agents that VM initialization is complete - nop if no agents. 796 JvmtiExport::post_vm_initialized(); 797 798 JFR_ONLY(Jfr::on_create_vm_3();) 799 800 #if INCLUDE_MANAGEMENT 801 Management::initialize(THREAD); 802 803 if (HAS_PENDING_EXCEPTION) { 804 // management agent fails to start possibly due to 805 // configuration problem and is responsible for printing 806 // stack trace if appropriate. Simply exit VM. 807 vm_exit(1); 808 } 809 #endif // INCLUDE_MANAGEMENT 810 811 StatSampler::engage(); 812 if (CheckJNICalls) JniPeriodicChecker::engage(); 813 814 call_postVMInitHook(THREAD); 815 // The Java side of PostVMInitHook.run must deal with all 816 // exceptions and provide means of diagnosis. 817 if (HAS_PENDING_EXCEPTION) { 818 CLEAR_PENDING_EXCEPTION; 819 } 820 821 // Let WatcherThread run all registered periodic tasks now. 822 // NOTE: All PeriodicTasks should be registered by now. If they 823 // aren't, late joiners might appear to start slowly (we might 824 // take a while to process their first tick). 825 WatcherThread::run_all_tasks(); 826 827 create_vm_timer.end(); 828 #ifdef ASSERT 829 _vm_complete = true; 830 #endif 831 832 if (CDSConfig::is_dumping_static_archive()) { 833 MetaspaceShared::preload_and_dump(CHECK_JNI_ERR); 834 } 835 836 if (log_is_enabled(Info, perf, class, link)) { 837 LogStreamHandle(Info, perf, class, link) log; 838 log.print_cr("At VM initialization completion:"); 839 ClassLoader::print_counters(&log); 840 } 841 842 return JNI_OK; 843 } 844 845 // Threads::destroy_vm() is normally called from jni_DestroyJavaVM() when 846 // the program falls off the end of main(). Another VM exit path is through 847 // vm_exit(), when the program calls System.exit() to return a value, or when 848 // there is a serious error in VM. 849 // These two separate shutdown paths are not exactly the same, but they share 850 // Shutdown.shutdown() at Java level and before_exit() and VM_Exit op at VM level. 851 // 852 // Shutdown sequence: 853 // + Shutdown native memory tracking if it is on 854 // + Wait until we are the last non-daemon thread to execute 855 // <-- every thing is still working at this moment --> 856 // + Call java.lang.Shutdown.shutdown(), which will invoke Java level 857 // shutdown hooks 858 // + Call before_exit(), prepare for VM exit 859 // > run VM level shutdown hooks (they are registered through JVM_OnExit(), 860 // currently the only user of this mechanism is File.deleteOnExit()) 861 // > stop StatSampler, watcher thread, 862 // post thread end and vm death events to JVMTI, 863 // stop signal thread 864 // + Call JavaThread::exit(), it will: 865 // > release JNI handle blocks, remove stack guard pages 866 // > remove this thread from Threads list 867 // <-- no more Java code from this thread after this point --> 868 // + Stop VM thread, it will bring the remaining VM to a safepoint and stop 869 // the compiler threads at safepoint 870 // <-- do not use anything that could get blocked by Safepoint --> 871 // + Disable tracing at JNI/JVM barriers 872 // + Set _vm_exited flag for threads that are still running native code 873 // + Call exit_globals() 874 // > deletes tty 875 // > deletes PerfMemory resources 876 // + Delete this thread 877 // + Return to caller 878 879 void Threads::destroy_vm() { 880 JavaThread* thread = JavaThread::current(); 881 882 #ifdef ASSERT 883 _vm_complete = false; 884 #endif 885 // Wait until we are the last non-daemon thread to execute, or 886 // if we are a daemon then wait until the last non-daemon thread has 887 // executed. 888 bool daemon = java_lang_Thread::is_daemon(thread->threadObj()); 889 int expected = daemon ? 0 : 1; 890 { 891 MonitorLocker nu(Threads_lock); 892 while (Threads::number_of_non_daemon_threads() > expected) 893 // This wait should make safepoint checks, wait without a timeout. 894 nu.wait(0); 895 } 896 897 EventShutdown e; 898 if (e.should_commit()) { 899 e.set_reason("No remaining non-daemon Java threads"); 900 e.commit(); 901 } 902 903 // Hang forever on exit if we are reporting an error. 904 if (ShowMessageBoxOnError && VMError::is_error_reported()) { 905 os::infinite_sleep(); 906 } 907 os::wait_for_keypress_at_exit(); 908 909 // run Java level shutdown hooks 910 thread->invoke_shutdown_hooks(); 911 912 before_exit(thread); 913 914 thread->exit(true); 915 916 // We are no longer on the main thread list but could still be in a 917 // secondary list where another thread may try to interact with us. 918 // So wait until all such interactions are complete before we bring 919 // the VM to the termination safepoint. Normally this would be done 920 // using thread->smr_delete() below where we delete the thread, but 921 // we can't call that after the termination safepoint is active as 922 // we will deadlock on the Threads_lock. Once all interactions are 923 // complete it is safe to directly delete the thread at any time. 924 ThreadsSMRSupport::wait_until_not_protected(thread); 925 926 // Stop VM thread. 927 { 928 // 4945125 The vm thread comes to a safepoint during exit. 929 // GC vm_operations can get caught at the safepoint, and the 930 // heap is unparseable if they are caught. Grab the Heap_lock 931 // to prevent this. The GC vm_operations will not be able to 932 // queue until after the vm thread is dead. After this point, 933 // we'll never emerge out of the safepoint before the VM exits. 934 // Assert that the thread is terminated so that acquiring the 935 // Heap_lock doesn't cause the terminated thread to participate in 936 // the safepoint protocol. 937 938 assert(thread->is_terminated(), "must be terminated here"); 939 MutexLocker ml(Heap_lock); 940 941 VMThread::wait_for_vm_thread_exit(); 942 assert(SafepointSynchronize::is_at_safepoint(), "VM thread should exit at Safepoint"); 943 VMThread::destroy(); 944 } 945 946 // Now, all Java threads are gone except daemon threads. Daemon threads 947 // running Java code or in VM are stopped by the Safepoint. However, 948 // daemon threads executing native code are still running. But they 949 // will be stopped at native=>Java/VM barriers. Note that we can't 950 // simply kill or suspend them, as it is inherently deadlock-prone. 951 952 VM_Exit::set_vm_exited(); 953 954 // Clean up ideal graph printers after the VMThread has started 955 // the final safepoint which will block all the Compiler threads. 956 // Note that this Thread has already logically exited so the 957 // clean_up() function's use of a JavaThreadIteratorWithHandle 958 // would be a problem except set_vm_exited() has remembered the 959 // shutdown thread which is granted a policy exception. 960 #if defined(COMPILER2) && !defined(PRODUCT) 961 IdealGraphPrinter::clean_up(); 962 #endif 963 964 notify_vm_shutdown(); 965 966 // exit_globals() will delete tty 967 exit_globals(); 968 969 // Deleting the shutdown thread here is safe. See comment on 970 // wait_until_not_protected() above. 971 delete thread; 972 973 #if INCLUDE_JVMCI 974 if (JVMCICounterSize > 0) { 975 FREE_C_HEAP_ARRAY(jlong, JavaThread::_jvmci_old_thread_counters); 976 } 977 #endif 978 979 LogConfiguration::finalize(); 980 } 981 982 983 jboolean Threads::is_supported_jni_version_including_1_1(jint version) { 984 if (version == JNI_VERSION_1_1) return JNI_TRUE; 985 return is_supported_jni_version(version); 986 } 987 988 989 jboolean Threads::is_supported_jni_version(jint version) { 990 if (version == JNI_VERSION_1_2) return JNI_TRUE; 991 if (version == JNI_VERSION_1_4) return JNI_TRUE; 992 if (version == JNI_VERSION_1_6) return JNI_TRUE; 993 if (version == JNI_VERSION_1_8) return JNI_TRUE; 994 if (version == JNI_VERSION_9) return JNI_TRUE; 995 if (version == JNI_VERSION_10) return JNI_TRUE; 996 if (version == JNI_VERSION_19) return JNI_TRUE; 997 if (version == JNI_VERSION_20) return JNI_TRUE; 998 if (version == JNI_VERSION_21) return JNI_TRUE; 999 if (version == JNI_VERSION_24) return JNI_TRUE; 1000 return JNI_FALSE; 1001 } 1002 1003 void Threads::add(JavaThread* p, bool force_daemon) { 1004 // The threads lock must be owned at this point 1005 assert(Threads_lock->owned_by_self(), "must have threads lock"); 1006 1007 BarrierSet::barrier_set()->on_thread_attach(p); 1008 1009 // Once a JavaThread is added to the Threads list, smr_delete() has 1010 // to be used to delete it. Otherwise we can just delete it directly. 1011 p->set_on_thread_list(); 1012 1013 _number_of_threads++; 1014 oop threadObj = p->threadObj(); 1015 bool daemon = true; 1016 // Bootstrapping problem: threadObj can be null for initial 1017 // JavaThread (or for threads attached via JNI) 1018 if (!force_daemon && 1019 (threadObj == nullptr || !java_lang_Thread::is_daemon(threadObj))) { 1020 _number_of_non_daemon_threads++; 1021 daemon = false; 1022 } 1023 1024 ThreadService::add_thread(p, daemon); 1025 1026 // Maintain fast thread list 1027 ThreadsSMRSupport::add_thread(p); 1028 1029 // Increase the ObjectMonitor ceiling for the new thread. 1030 ObjectSynchronizer::inc_in_use_list_ceiling(); 1031 1032 // Possible GC point. 1033 Events::log(Thread::current(), "Thread added: " INTPTR_FORMAT, p2i(p)); 1034 1035 // Make new thread known to active EscapeBarrier 1036 EscapeBarrier::thread_added(p); 1037 } 1038 1039 void Threads::remove(JavaThread* p, bool is_daemon) { 1040 // Extra scope needed for Thread_lock, so we can check 1041 // that we do not remove thread without safepoint code notice 1042 { 1043 ConditionalMutexLocker throttle_ml(ThreadsLockThrottle_lock, UseThreadsLockThrottleLock); 1044 MonitorLocker ml(Threads_lock); 1045 1046 if (ThreadIdTable::is_initialized()) { 1047 // This cleanup must be done before the current thread's GC barrier 1048 // is detached since we need to touch the threadObj oop. 1049 jlong tid = SharedRuntime::get_java_tid(p); 1050 ThreadIdTable::remove_thread(tid); 1051 } 1052 1053 // BarrierSet state must be destroyed after the last thread transition 1054 // before the thread terminates. Thread transitions result in calls to 1055 // StackWatermarkSet::on_safepoint(), which performs GC processing, 1056 // requiring the GC state to be alive. 1057 BarrierSet::barrier_set()->on_thread_detach(p); 1058 if (p->is_exiting()) { 1059 // If we got here via JavaThread::exit(), then we remember that the 1060 // thread's GC barrier has been detached. We don't do this when we get 1061 // here from another path, e.g., cleanup_failed_attach_current_thread(). 1062 p->set_terminated(JavaThread::_thread_gc_barrier_detached); 1063 } 1064 1065 assert(ThreadsSMRSupport::get_java_thread_list()->includes(p), "p must be present"); 1066 1067 // Maintain fast thread list 1068 ThreadsSMRSupport::remove_thread(p); 1069 1070 _number_of_threads--; 1071 if (!is_daemon) { 1072 _number_of_non_daemon_threads--; 1073 1074 // If this is the last non-daemon thread then we need to do 1075 // a notify on the Threads_lock so a thread waiting 1076 // on destroy_vm will wake up. But that thread could be a daemon 1077 // or non-daemon, so we notify for both the 0 and 1 case. 1078 if (number_of_non_daemon_threads() <= 1) { 1079 ml.notify_all(); 1080 } 1081 } 1082 ThreadService::remove_thread(p, is_daemon); 1083 1084 // Make sure that safepoint code disregard this thread. This is needed since 1085 // the thread might mess around with locks after this point. This can cause it 1086 // to do callbacks into the safepoint code. However, the safepoint code is not aware 1087 // of this thread since it is removed from the queue. 1088 p->set_terminated(JavaThread::_thread_terminated); 1089 1090 // Notify threads waiting in EscapeBarriers 1091 EscapeBarrier::thread_removed(p); 1092 } // unlock Threads_lock and ThreadsLockThrottle_lock 1093 1094 // Reduce the ObjectMonitor ceiling for the exiting thread. 1095 ObjectSynchronizer::dec_in_use_list_ceiling(); 1096 1097 // Since Events::log uses a lock, we grab it outside the Threads_lock 1098 Events::log(Thread::current(), "Thread exited: " INTPTR_FORMAT, p2i(p)); 1099 } 1100 1101 // Operations on the Threads list for GC. These are not explicitly locked, 1102 // but the garbage collector must provide a safe context for them to run. 1103 // In particular, these things should never be called when the Threads_lock 1104 // is held by some other thread. (Note: the Safepoint abstraction also 1105 // uses the Threads_lock to guarantee this property. It also makes sure that 1106 // all threads gets blocked when exiting or starting). 1107 1108 void Threads::oops_do(OopClosure* f, NMethodClosure* cf) { 1109 ALL_JAVA_THREADS(p) { 1110 p->oops_do(f, cf); 1111 } 1112 VMThread::vm_thread()->oops_do(f, cf); 1113 } 1114 1115 void Threads::change_thread_claim_token() { 1116 if (++_thread_claim_token == 0) { 1117 // On overflow of the token counter, there is a risk of future 1118 // collisions between a new global token value and a stale token 1119 // for a thread, because not all iterations visit all threads. 1120 // (Though it's pretty much a theoretical concern for non-trivial 1121 // token counter sizes.) To deal with the possibility, reset all 1122 // the thread tokens to zero on global token overflow. 1123 struct ResetClaims : public ThreadClosure { 1124 virtual void do_thread(Thread* t) { 1125 t->claim_threads_do(false, 0); 1126 } 1127 } reset_claims; 1128 Threads::threads_do(&reset_claims); 1129 // On overflow, update the global token to non-zero, to 1130 // avoid the special "never claimed" initial thread value. 1131 _thread_claim_token = 1; 1132 } 1133 } 1134 1135 #ifdef ASSERT 1136 static void assert_thread_claimed(const char* kind, Thread* t, uintx expected) { 1137 const uintx token = t->threads_do_token(); 1138 assert(token == expected, 1139 "%s " PTR_FORMAT " has incorrect value " UINTX_FORMAT " != " 1140 UINTX_FORMAT, kind, p2i(t), token, expected); 1141 } 1142 1143 void Threads::assert_all_threads_claimed() { 1144 ALL_JAVA_THREADS(p) { 1145 assert_thread_claimed("JavaThread", p, _thread_claim_token); 1146 } 1147 1148 struct NJTClaimedVerifierClosure : public ThreadClosure { 1149 uintx _thread_claim_token; 1150 1151 NJTClaimedVerifierClosure(uintx thread_claim_token) : ThreadClosure(), _thread_claim_token(thread_claim_token) { } 1152 1153 virtual void do_thread(Thread* thread) override { 1154 assert_thread_claimed("Non-JavaThread", VMThread::vm_thread(), _thread_claim_token); 1155 } 1156 } tc(_thread_claim_token); 1157 1158 non_java_threads_do(&tc); 1159 } 1160 #endif // ASSERT 1161 1162 class ParallelOopsDoThreadClosure : public ThreadClosure { 1163 private: 1164 OopClosure* _f; 1165 NMethodClosure* _cf; 1166 public: 1167 ParallelOopsDoThreadClosure(OopClosure* f, NMethodClosure* cf) : _f(f), _cf(cf) {} 1168 void do_thread(Thread* t) { 1169 t->oops_do(_f, _cf); 1170 } 1171 }; 1172 1173 void Threads::possibly_parallel_oops_do(bool is_par, OopClosure* f, NMethodClosure* cf) { 1174 ParallelOopsDoThreadClosure tc(f, cf); 1175 possibly_parallel_threads_do(is_par, &tc); 1176 } 1177 1178 void Threads::metadata_do(MetadataClosure* f) { 1179 ALL_JAVA_THREADS(p) { 1180 p->metadata_do(f); 1181 } 1182 } 1183 1184 class ThreadHandlesClosure : public ThreadClosure { 1185 void (*_f)(Metadata*); 1186 public: 1187 ThreadHandlesClosure(void f(Metadata*)) : _f(f) {} 1188 virtual void do_thread(Thread* thread) { 1189 thread->metadata_handles_do(_f); 1190 } 1191 }; 1192 1193 void Threads::metadata_handles_do(void f(Metadata*)) { 1194 // Only walk the Handles in Thread. 1195 ThreadHandlesClosure handles_closure(f); 1196 threads_do(&handles_closure); 1197 } 1198 1199 #if INCLUDE_JVMTI 1200 // Get Java threads that are waiting to enter or re-enter the specified monitor. 1201 // Java threads that are executing mounted virtual threads are not included. 1202 GrowableArray<JavaThread*>* Threads::get_pending_threads(ThreadsList * t_list, 1203 int count, 1204 address monitor) { 1205 assert(Thread::current()->is_VM_thread(), "Must be the VM thread"); 1206 GrowableArray<JavaThread*>* result = new GrowableArray<JavaThread*>(count); 1207 1208 int i = 0; 1209 for (JavaThread* p : *t_list) { 1210 if (!p->can_call_java()) continue; 1211 1212 oop thread_oop = JvmtiEnvBase::get_vthread_or_thread_oop(p); 1213 if (thread_oop->is_a(vmClasses::BaseVirtualThread_klass())) { 1214 continue; 1215 } 1216 // The first stage of async deflation does not affect any field 1217 // used by this comparison so the ObjectMonitor* is usable here. 1218 address pending = (address)p->current_pending_monitor(); 1219 address waiting = (address)p->current_waiting_monitor(); 1220 // do not include virtual threads to the list 1221 jint state = JvmtiEnvBase::get_thread_state(thread_oop, p); 1222 if (pending == monitor || (waiting == monitor && 1223 (state & JVMTI_THREAD_STATE_BLOCKED_ON_MONITOR_ENTER)) 1224 ) { // found a match 1225 if (i < count) result->append(p); // save the first count matches 1226 i++; 1227 } 1228 } 1229 1230 return result; 1231 } 1232 #endif // INCLUDE_JVMTI 1233 1234 JavaThread *Threads::owning_thread_from_monitor_owner(ThreadsList * t_list, 1235 address owner) { 1236 assert(LockingMode != LM_LIGHTWEIGHT, "Not with new lightweight locking"); 1237 // null owner means not locked so we can skip the search 1238 if (owner == nullptr) return nullptr; 1239 1240 for (JavaThread* p : *t_list) { 1241 // first, see if owner is the address of a Java thread 1242 if (owner == (address)p) return p; 1243 } 1244 1245 // Cannot assert on lack of success here since this function may be 1246 // used by code that is trying to report useful problem information 1247 // like deadlock detection. 1248 if (LockingMode == LM_MONITOR) return nullptr; 1249 1250 // If we didn't find a matching Java thread and we didn't force use of 1251 // heavyweight monitors, then the owner is the stack address of the 1252 // Lock Word in the owning Java thread's stack. 1253 // 1254 JavaThread* the_owner = nullptr; 1255 for (JavaThread* q : *t_list) { 1256 if (q->is_lock_owned(owner)) { 1257 the_owner = q; 1258 break; 1259 } 1260 } 1261 1262 // cannot assert on lack of success here; see above comment 1263 return the_owner; 1264 } 1265 1266 JavaThread* Threads::owning_thread_from_object(ThreadsList * t_list, oop obj) { 1267 assert(LockingMode == LM_LIGHTWEIGHT, "Only with new lightweight locking"); 1268 for (JavaThread* q : *t_list) { 1269 // Need to start processing before accessing oops in the thread. 1270 StackWatermark* watermark = StackWatermarkSet::get(q, StackWatermarkKind::gc); 1271 if (watermark != nullptr) { 1272 watermark->start_processing(); 1273 } 1274 1275 if (q->lock_stack().contains(obj)) { 1276 return q; 1277 } 1278 } 1279 return nullptr; 1280 } 1281 1282 JavaThread* Threads::owning_thread_from_monitor(ThreadsList* t_list, ObjectMonitor* monitor) { 1283 if (LockingMode == LM_LIGHTWEIGHT) { 1284 if (monitor->is_owner_anonymous()) { 1285 return owning_thread_from_object(t_list, monitor->object()); 1286 } else { 1287 Thread* owner = reinterpret_cast<Thread*>(monitor->owner()); 1288 assert(owner == nullptr || owner->is_Java_thread(), "only JavaThreads own monitors"); 1289 return reinterpret_cast<JavaThread*>(owner); 1290 } 1291 } else { 1292 address owner = (address)monitor->owner(); 1293 return owning_thread_from_monitor_owner(t_list, owner); 1294 } 1295 } 1296 1297 class PrintOnClosure : public ThreadClosure { 1298 private: 1299 outputStream* _st; 1300 1301 public: 1302 PrintOnClosure(outputStream* st) : 1303 _st(st) {} 1304 1305 virtual void do_thread(Thread* thread) { 1306 if (thread != nullptr) { 1307 thread->print_on(_st); 1308 _st->cr(); 1309 } 1310 } 1311 }; 1312 1313 // Threads::print_on() is called at safepoint by VM_PrintThreads operation. 1314 void Threads::print_on(outputStream* st, bool print_stacks, 1315 bool internal_format, bool print_concurrent_locks, 1316 bool print_extended_info) { 1317 char buf[32]; 1318 st->print_raw_cr(os::local_time_string(buf, sizeof(buf))); 1319 1320 st->print_cr("Full thread dump %s (%s %s):", 1321 VM_Version::vm_name(), 1322 VM_Version::vm_release(), 1323 VM_Version::vm_info_string()); 1324 st->cr(); 1325 1326 #if INCLUDE_SERVICES 1327 // Dump concurrent locks 1328 ConcurrentLocksDump concurrent_locks; 1329 if (print_concurrent_locks) { 1330 concurrent_locks.dump_at_safepoint(); 1331 } 1332 #endif // INCLUDE_SERVICES 1333 1334 ThreadsSMRSupport::print_info_on(st); 1335 st->cr(); 1336 1337 ALL_JAVA_THREADS(p) { 1338 ResourceMark rm; 1339 p->print_on(st, print_extended_info); 1340 if (print_stacks) { 1341 if (internal_format) { 1342 p->trace_stack(); 1343 } else { 1344 p->print_stack_on(st); 1345 const oop thread_oop = p->threadObj(); 1346 if (thread_oop != nullptr) { 1347 if (p->is_vthread_mounted()) { 1348 const oop vt = p->vthread(); 1349 assert(vt != nullptr, "vthread should not be null when vthread is mounted"); 1350 // JavaThread._vthread can refer to the carrier thread. Print only if _vthread refers to a virtual thread. 1351 if (vt != thread_oop) { 1352 st->print_cr(" Mounted virtual thread #" INT64_FORMAT, (int64_t)java_lang_Thread::thread_id(vt)); 1353 p->print_vthread_stack_on(st); 1354 } 1355 } 1356 } 1357 } 1358 } 1359 st->cr(); 1360 #if INCLUDE_SERVICES 1361 if (print_concurrent_locks) { 1362 concurrent_locks.print_locks_on(p, st); 1363 } 1364 #endif // INCLUDE_SERVICES 1365 } 1366 1367 PrintOnClosure cl(st); 1368 non_java_threads_do(&cl); 1369 1370 st->flush(); 1371 } 1372 1373 void Threads::print_on_error(Thread* this_thread, outputStream* st, Thread* current, char* buf, 1374 int buflen, bool* found_current) { 1375 if (this_thread != nullptr) { 1376 bool is_current = (current == this_thread); 1377 *found_current = *found_current || is_current; 1378 st->print("%s", is_current ? "=>" : " "); 1379 1380 st->print(PTR_FORMAT, p2i(this_thread)); 1381 st->print(" "); 1382 this_thread->print_on_error(st, buf, buflen); 1383 st->cr(); 1384 } 1385 } 1386 1387 class PrintOnErrorClosure : public ThreadClosure { 1388 outputStream* _st; 1389 Thread* _current; 1390 char* _buf; 1391 int _buflen; 1392 bool* _found_current; 1393 unsigned _num_printed; 1394 public: 1395 PrintOnErrorClosure(outputStream* st, Thread* current, char* buf, 1396 int buflen, bool* found_current) : 1397 _st(st), _current(current), _buf(buf), _buflen(buflen), _found_current(found_current), 1398 _num_printed(0) {} 1399 1400 virtual void do_thread(Thread* thread) { 1401 _num_printed++; 1402 Threads::print_on_error(thread, _st, _current, _buf, _buflen, _found_current); 1403 } 1404 1405 unsigned num_printed() const { return _num_printed; } 1406 }; 1407 1408 // Threads::print_on_error() is called by fatal error handler. It's possible 1409 // that VM is not at safepoint and/or current thread is inside signal handler. 1410 // Don't print stack trace, as the stack may not be walkable. Don't allocate 1411 // memory (even in resource area), it might deadlock the error handler. 1412 void Threads::print_on_error(outputStream* st, Thread* current, char* buf, 1413 int buflen) { 1414 ThreadsSMRSupport::print_info_on(st); 1415 st->cr(); 1416 1417 bool found_current = false; 1418 st->print_cr("Java Threads: ( => current thread )"); 1419 unsigned num_java = 0; 1420 ALL_JAVA_THREADS(thread) { 1421 print_on_error(thread, st, current, buf, buflen, &found_current); 1422 num_java++; 1423 } 1424 st->print_cr("Total: %u", num_java); 1425 st->cr(); 1426 1427 st->print_cr("Other Threads:"); 1428 unsigned num_other = ((VMThread::vm_thread() != nullptr) ? 1 : 0) + 1429 ((WatcherThread::watcher_thread() != nullptr) ? 1 : 0) + 1430 ((AsyncLogWriter::instance() != nullptr) ? 1 : 0); 1431 print_on_error(VMThread::vm_thread(), st, current, buf, buflen, &found_current); 1432 print_on_error(WatcherThread::watcher_thread(), st, current, buf, buflen, &found_current); 1433 print_on_error(AsyncLogWriter::instance(), st, current, buf, buflen, &found_current); 1434 1435 if (Universe::heap() != nullptr) { 1436 PrintOnErrorClosure print_closure(st, current, buf, buflen, &found_current); 1437 Universe::heap()->gc_threads_do(&print_closure); 1438 num_other += print_closure.num_printed(); 1439 } 1440 1441 if (!found_current) { 1442 st->cr(); 1443 st->print("=>" PTR_FORMAT " (exited) ", p2i(current)); 1444 current->print_on_error(st, buf, buflen); 1445 num_other++; 1446 st->cr(); 1447 } 1448 st->print_cr("Total: %u", num_other); 1449 st->cr(); 1450 1451 st->print_cr("Threads with active compile tasks:"); 1452 unsigned num = print_threads_compiling(st, buf, buflen); 1453 st->print_cr("Total: %u", num); 1454 } 1455 1456 unsigned Threads::print_threads_compiling(outputStream* st, char* buf, int buflen, bool short_form) { 1457 unsigned num = 0; 1458 ALL_JAVA_THREADS(thread) { 1459 if (thread->is_Compiler_thread()) { 1460 CompilerThread* ct = (CompilerThread*) thread; 1461 1462 // Keep task in local variable for null check. 1463 // ct->_task might be set to null by concurring compiler thread 1464 // because it completed the compilation. The task is never freed, 1465 // though, just returned to a free list. 1466 CompileTask* task = ct->task(); 1467 if (task != nullptr) { 1468 thread->print_name_on_error(st, buf, buflen); 1469 st->print(" "); 1470 task->print(st, nullptr, short_form, true); 1471 num++; 1472 } 1473 } 1474 } 1475 return num; 1476 } 1477 1478 void Threads::verify() { 1479 ALL_JAVA_THREADS(p) { 1480 p->verify(); 1481 } 1482 VMThread* thread = VMThread::vm_thread(); 1483 if (thread != nullptr) thread->verify(); 1484 }