1 2 /* 3 * Copyright (c) 1997, 2025, Oracle and/or its affiliates. All rights reserved. 4 * Copyright (c) 2021, Azul Systems, Inc. All rights reserved. 5 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 6 * 7 * This code is free software; you can redistribute it and/or modify it 8 * under the terms of the GNU General Public License version 2 only, as 9 * published by the Free Software Foundation. 10 * 11 * This code is distributed in the hope that it will be useful, but WITHOUT 12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 14 * version 2 for more details (a copy is included in the LICENSE file that 15 * accompanied this code). 16 * 17 * You should have received a copy of the GNU General Public License version 18 * 2 along with this work; if not, write to the Free Software Foundation, 19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 20 * 21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 22 * or visit www.oracle.com if you need additional information or have any 23 * questions. 24 * 25 */ 26 27 #include "cds/aotLinkedClassBulkLoader.hpp" 28 #include "cds/cds_globals.hpp" 29 #include "cds/cdsConfig.hpp" 30 #include "cds/heapShared.hpp" 31 #include "cds/metaspaceShared.hpp" 32 #include "cds/methodProfiler.hpp" 33 #include "classfile/classLoader.hpp" 34 #include "classfile/javaClasses.hpp" 35 #include "classfile/javaThreadStatus.hpp" 36 #include "classfile/symbolTable.hpp" 37 #include "classfile/systemDictionary.hpp" 38 #include "classfile/systemDictionaryShared.hpp" 39 #include "classfile/vmClasses.hpp" 40 #include "classfile/vmSymbols.hpp" 41 #include "code/aotCodeCache.hpp" 42 #include "compiler/compilationPolicy.hpp" 43 #include "compiler/compileBroker.hpp" 44 #include "compiler/compileTask.hpp" 45 #include "compiler/compilerThread.hpp" 46 #include "compiler/precompiler.hpp" 47 #include "gc/shared/barrierSet.hpp" 48 #include "gc/shared/barrierSetNMethod.hpp" 49 #include "gc/shared/gcVMOperations.hpp" 50 #include "gc/shared/oopStorage.hpp" 51 #include "gc/shared/oopStorageSet.hpp" 52 #include "gc/shared/stringdedup/stringDedup.hpp" 53 #include "interpreter/interpreterRuntime.hpp" 54 #include "jfr/jfrEvents.hpp" 55 #include "jvm.h" 56 #include "jvmtifiles/jvmtiEnv.hpp" 57 #include "logging/log.hpp" 58 #include "logging/logAsyncWriter.hpp" 59 #include "logging/logConfiguration.hpp" 60 #include "memory/allocation.inline.hpp" 61 #include "memory/iterator.hpp" 62 #include "memory/oopFactory.hpp" 63 #include "memory/resourceArea.hpp" 64 #include "memory/universe.hpp" 65 #include "nmt/memTracker.hpp" 66 #include "oops/instanceKlass.hpp" 67 #include "oops/klass.inline.hpp" 68 #include "oops/oop.inline.hpp" 69 #include "oops/symbol.hpp" 70 #include "prims/jvm_misc.hpp" 71 #include "prims/jvmtiAgentList.hpp" 72 #include "prims/jvmtiEnvBase.hpp" 73 #include "runtime/arguments.hpp" 74 #include "runtime/fieldDescriptor.inline.hpp" 75 #include "runtime/flags/jvmFlagLimit.hpp" 76 #include "runtime/globals.hpp" 77 #include "runtime/globals_extension.hpp" 78 #include "runtime/handles.inline.hpp" 79 #include "runtime/interfaceSupport.inline.hpp" 80 #include "runtime/java.hpp" 81 #include "runtime/javaCalls.hpp" 82 #include "runtime/javaThread.inline.hpp" 83 #include "runtime/jniHandles.inline.hpp" 84 #include "runtime/jniPeriodicChecker.hpp" 85 #include "runtime/lockStack.inline.hpp" 86 #include "runtime/monitorDeflationThread.hpp" 87 #include "runtime/mutexLocker.hpp" 88 #include "runtime/nonJavaThread.hpp" 89 #include "runtime/objectMonitor.inline.hpp" 90 #include "runtime/osThread.hpp" 91 #include "runtime/perfData.hpp" 92 #include "runtime/safepoint.hpp" 93 #include "runtime/safepointMechanism.inline.hpp" 94 #include "runtime/safepointVerifiers.hpp" 95 #include "runtime/serviceThread.hpp" 96 #include "runtime/sharedRuntime.hpp" 97 #include "runtime/stackWatermarkSet.inline.hpp" 98 #include "runtime/stubCodeGenerator.hpp" 99 #include "runtime/thread.inline.hpp" 100 #include "runtime/threadSMR.inline.hpp" 101 #include "runtime/threads.hpp" 102 #include "runtime/timer.hpp" 103 #include "runtime/timerTrace.hpp" 104 #include "runtime/trimNativeHeap.hpp" 105 #include "runtime/vmOperations.hpp" 106 #include "runtime/vm_version.hpp" 107 #include "services/attachListener.hpp" 108 #include "services/management.hpp" 109 #include "services/threadIdTable.hpp" 110 #include "services/threadService.hpp" 111 #include "utilities/dtrace.hpp" 112 #include "utilities/events.hpp" 113 #include "utilities/macros.hpp" 114 #include "utilities/vmError.hpp" 115 #if INCLUDE_JVMCI 116 #include "jvmci/jvmci.hpp" 117 #include "jvmci/jvmciEnv.hpp" 118 #endif 119 #ifdef COMPILER1 120 #include "c1/c1_Runtime1.hpp" 121 #endif 122 #ifdef COMPILER2 123 #include "opto/idealGraphPrinter.hpp" 124 #include "opto/runtime.hpp" 125 #endif 126 #if INCLUDE_JFR 127 #include "jfr/jfr.hpp" 128 #endif 129 130 // Initialization after module runtime initialization 131 void universe_post_module_init(); // must happen after call_initPhase2 132 133 134 static void initialize_class(Symbol* class_name, TRAPS) { 135 Klass* klass = SystemDictionary::resolve_or_fail(class_name, true, CHECK); 136 InstanceKlass::cast(klass)->initialize(CHECK); 137 } 138 139 140 // Creates the initial ThreadGroup 141 static Handle create_initial_thread_group(TRAPS) { 142 Handle system_instance = JavaCalls::construct_new_instance( 143 vmClasses::ThreadGroup_klass(), 144 vmSymbols::void_method_signature(), 145 CHECK_NH); 146 Universe::set_system_thread_group(system_instance()); 147 148 Handle string = java_lang_String::create_from_str("main", CHECK_NH); 149 Handle main_instance = JavaCalls::construct_new_instance( 150 vmClasses::ThreadGroup_klass(), 151 vmSymbols::threadgroup_string_void_signature(), 152 system_instance, 153 string, 154 CHECK_NH); 155 return main_instance; 156 } 157 158 // Creates the initial Thread, and sets it to running. 159 static void create_initial_thread(Handle thread_group, JavaThread* thread, 160 TRAPS) { 161 InstanceKlass* ik = vmClasses::Thread_klass(); 162 assert(ik->is_initialized(), "must be"); 163 instanceHandle thread_oop = ik->allocate_instance_handle(CHECK); 164 165 // Cannot use JavaCalls::construct_new_instance because the java.lang.Thread 166 // constructor calls Thread.current(), which must be set here for the 167 // initial thread. 168 java_lang_Thread::set_thread(thread_oop(), thread); 169 thread->set_threadOopHandles(thread_oop()); 170 171 Handle string = java_lang_String::create_from_str("main", CHECK); 172 173 JavaValue result(T_VOID); 174 JavaCalls::call_special(&result, thread_oop, 175 ik, 176 vmSymbols::object_initializer_name(), 177 vmSymbols::threadgroup_string_void_signature(), 178 thread_group, 179 string, 180 CHECK); 181 182 DEBUG_ONLY(int64_t main_thread_tid = java_lang_Thread::thread_id(thread_oop());) 183 assert(main_thread_tid == ThreadIdentifier::initial(), ""); 184 assert(main_thread_tid == thread->monitor_owner_id(), ""); 185 JFR_ONLY(assert(JFR_JVM_THREAD_ID(thread) == static_cast<traceid>(main_thread_tid), "initial tid mismatch");) 186 187 // Set thread status to running since main thread has 188 // been started and running. 189 java_lang_Thread::set_thread_status(thread_oop(), 190 JavaThreadStatus::RUNNABLE); 191 } 192 193 // Extract version and vendor specific information from 194 // java.lang.VersionProps fields. 195 // Returned char* is allocated in the thread's resource area 196 // so must be copied for permanency. 197 static const char* get_java_version_info(InstanceKlass* ik, 198 Symbol* field_name) { 199 fieldDescriptor fd; 200 bool found = ik != nullptr && 201 ik->find_local_field(field_name, 202 vmSymbols::string_signature(), &fd); 203 if (found) { 204 oop name_oop = ik->java_mirror()->obj_field(fd.offset()); 205 if (name_oop == nullptr) { 206 return nullptr; 207 } 208 const char* name = java_lang_String::as_utf8_string(name_oop); 209 return name; 210 } else { 211 return nullptr; 212 } 213 } 214 215 // ======= Threads ======== 216 217 // The Threads class links together all active threads, and provides 218 // operations over all threads. It is protected by the Threads_lock, 219 // which is also used in other global contexts like safepointing. 220 // ThreadsListHandles are used to safely perform operations on one 221 // or more threads without the risk of the thread exiting during the 222 // operation. 223 // 224 // Note: The Threads_lock is currently more widely used than we 225 // would like. We are actively migrating Threads_lock uses to other 226 // mechanisms in order to reduce Threads_lock contention. 227 228 int Threads::_number_of_threads = 0; 229 int Threads::_number_of_non_daemon_threads = 0; 230 int Threads::_return_code = 0; 231 uintx Threads::_thread_claim_token = 1; // Never zero. 232 233 #ifdef ASSERT 234 bool Threads::_vm_complete = false; 235 #endif 236 237 // General purpose hook into Java code, run once when the VM is initialized. 238 // The Java library method itself may be changed independently from the VM. 239 static void call_postVMInitHook(TRAPS) { 240 Klass* klass = SystemDictionary::resolve_or_null(vmSymbols::jdk_internal_vm_PostVMInitHook(), THREAD); 241 if (klass != nullptr) { 242 JavaValue result(T_VOID); 243 JavaCalls::call_static(&result, klass, vmSymbols::run_method_name(), 244 vmSymbols::void_method_signature(), 245 CHECK); 246 } 247 } 248 249 // All NonJavaThreads (i.e., every non-JavaThread in the system). 250 void Threads::non_java_threads_do(ThreadClosure* tc) { 251 NoSafepointVerifier nsv; 252 for (NonJavaThread::Iterator njti; !njti.end(); njti.step()) { 253 tc->do_thread(njti.current()); 254 } 255 } 256 257 // All JavaThreads 258 #define ALL_JAVA_THREADS(X) \ 259 for (JavaThread* X : *ThreadsSMRSupport::get_java_thread_list()) 260 261 // All JavaThreads 262 void Threads::java_threads_do(ThreadClosure* tc) { 263 assert_locked_or_safepoint(Threads_lock); 264 // ALL_JAVA_THREADS iterates through all JavaThreads. 265 ALL_JAVA_THREADS(p) { 266 tc->do_thread(p); 267 } 268 } 269 270 // All JavaThreads + all non-JavaThreads (i.e., every thread in the system). 271 void Threads::threads_do(ThreadClosure* tc) { 272 assert_locked_or_safepoint(Threads_lock); 273 java_threads_do(tc); 274 non_java_threads_do(tc); 275 } 276 277 void Threads::possibly_parallel_threads_do(bool is_par, ThreadClosure* tc) { 278 assert_at_safepoint(); 279 280 uintx claim_token = Threads::thread_claim_token(); 281 ALL_JAVA_THREADS(p) { 282 if (p->claim_threads_do(is_par, claim_token)) { 283 tc->do_thread(p); 284 } 285 } 286 for (NonJavaThread::Iterator njti; !njti.end(); njti.step()) { 287 Thread* current = njti.current(); 288 if (current->claim_threads_do(is_par, claim_token)) { 289 tc->do_thread(current); 290 } 291 } 292 } 293 294 // The system initialization in the library has three phases. 295 // 296 // Phase 1: java.lang.System class initialization 297 // java.lang.System is a primordial class loaded and initialized 298 // by the VM early during startup. java.lang.System.<clinit> 299 // only does registerNatives and keeps the rest of the class 300 // initialization work later until thread initialization completes. 301 // 302 // System.initPhase1 initializes the system properties, the static 303 // fields in, out, and err. Set up java signal handlers, OS-specific 304 // system settings, and thread group of the main thread. 305 static void call_initPhase1(TRAPS) { 306 Klass* klass = vmClasses::System_klass(); 307 JavaValue result(T_VOID); 308 JavaCalls::call_static(&result, klass, vmSymbols::initPhase1_name(), 309 vmSymbols::void_method_signature(), CHECK); 310 } 311 312 // Phase 2. Module system initialization 313 // This will initialize the module system. Only java.base classes 314 // can be loaded until phase 2 completes. 315 // 316 // Call System.initPhase2 after the compiler initialization and jsr292 317 // classes get initialized because module initialization runs a lot of java 318 // code, that for performance reasons, should be compiled. Also, this will 319 // enable the startup code to use lambda and other language features in this 320 // phase and onward. 321 // 322 // After phase 2, The VM will begin search classes from -Xbootclasspath/a. 323 static void call_initPhase2(TRAPS) { 324 TraceTime timer("Initialize module system", TRACETIME_LOG(Info, startuptime)); 325 326 Klass* klass = vmClasses::System_klass(); 327 328 JavaValue result(T_INT); 329 JavaCallArguments args; 330 args.push_int(DisplayVMOutputToStderr); 331 args.push_int(log_is_enabled(Debug, init)); // print stack trace if exception thrown 332 JavaCalls::call_static(&result, klass, vmSymbols::initPhase2_name(), 333 vmSymbols::boolean_boolean_int_signature(), &args, CHECK); 334 if (result.get_jint() != JNI_OK) { 335 vm_exit_during_initialization(); // no message or exception 336 } 337 338 universe_post_module_init(); 339 } 340 341 // Phase 3. final setup - set security manager, system class loader and TCCL 342 // 343 // This will instantiate and set the security manager, set the system class 344 // loader as well as the thread context class loader. The security manager 345 // and system class loader may be a custom class loaded from -Xbootclasspath/a, 346 // other modules or the application's classpath. 347 static void call_initPhase3(TRAPS) { 348 Klass* klass = vmClasses::System_klass(); 349 JavaValue result(T_VOID); 350 JavaCalls::call_static(&result, klass, vmSymbols::initPhase3_name(), 351 vmSymbols::void_method_signature(), CHECK); 352 } 353 354 void Threads::initialize_java_lang_classes(JavaThread* main_thread, TRAPS) { 355 TraceTime timer("Initialize java.lang classes", TRACETIME_LOG(Info, startuptime)); 356 357 initialize_class(vmSymbols::java_lang_String(), CHECK); 358 359 // Inject CompactStrings value after the static initializers for String ran. 360 java_lang_String::set_compact_strings(CompactStrings); 361 362 // Initialize java_lang.System (needed before creating the thread) 363 initialize_class(vmSymbols::java_lang_System(), CHECK); 364 // The VM creates & returns objects of this class. Make sure it's initialized. 365 initialize_class(vmSymbols::java_lang_Class(), CHECK); 366 367 initialize_class(vmSymbols::java_lang_ThreadGroup(), CHECK); 368 Handle thread_group = create_initial_thread_group(CHECK); 369 Universe::set_main_thread_group(thread_group()); 370 initialize_class(vmSymbols::java_lang_Thread(), CHECK); 371 create_initial_thread(thread_group, main_thread, CHECK); 372 373 HeapShared::init_box_classes(CHECK); 374 375 // The VM creates objects of this class. 376 initialize_class(vmSymbols::java_lang_Module(), CHECK); 377 378 #ifdef ASSERT 379 InstanceKlass *k = vmClasses::UnsafeConstants_klass(); 380 assert(k->is_not_initialized(), "UnsafeConstants should not already be initialized"); 381 #endif 382 383 // initialize the hardware-specific constants needed by Unsafe 384 initialize_class(vmSymbols::jdk_internal_misc_UnsafeConstants(), CHECK); 385 jdk_internal_misc_UnsafeConstants::set_unsafe_constants(); 386 387 // The VM preresolves methods to these classes. Make sure that they get initialized 388 initialize_class(vmSymbols::java_lang_reflect_Method(), CHECK); 389 initialize_class(vmSymbols::java_lang_ref_Finalizer(), CHECK); 390 391 // Phase 1 of the system initialization in the library, java.lang.System class initialization 392 call_initPhase1(CHECK); 393 394 // Get the Java runtime name, version, and vendor info after java.lang.System is initialized. 395 // Some values are actually configure-time constants but some can be set via the jlink tool and 396 // so must be read dynamically. We treat them all the same. 397 InstanceKlass* ik = SystemDictionary::find_instance_klass(THREAD, vmSymbols::java_lang_VersionProps(), 398 Handle()); 399 { 400 ResourceMark rm(main_thread); 401 JDK_Version::set_java_version(get_java_version_info(ik, vmSymbols::java_version_name())); 402 403 JDK_Version::set_runtime_name(get_java_version_info(ik, vmSymbols::java_runtime_name_name())); 404 405 JDK_Version::set_runtime_version(get_java_version_info(ik, vmSymbols::java_runtime_version_name())); 406 407 JDK_Version::set_runtime_vendor_version(get_java_version_info(ik, vmSymbols::java_runtime_vendor_version_name())); 408 409 JDK_Version::set_runtime_vendor_vm_bug_url(get_java_version_info(ik, vmSymbols::java_runtime_vendor_vm_bug_url_name())); 410 } 411 412 // an instance of OutOfMemory exception has been allocated earlier 413 initialize_class(vmSymbols::java_lang_OutOfMemoryError(), CHECK); 414 initialize_class(vmSymbols::java_lang_NullPointerException(), CHECK); 415 initialize_class(vmSymbols::java_lang_ClassCastException(), CHECK); 416 initialize_class(vmSymbols::java_lang_ArrayStoreException(), CHECK); 417 initialize_class(vmSymbols::java_lang_ArithmeticException(), CHECK); 418 initialize_class(vmSymbols::java_lang_ArrayIndexOutOfBoundsException(), CHECK); 419 initialize_class(vmSymbols::java_lang_StackOverflowError(), CHECK); 420 initialize_class(vmSymbols::java_lang_IllegalMonitorStateException(), CHECK); 421 initialize_class(vmSymbols::java_lang_IllegalArgumentException(), CHECK); 422 initialize_class(vmSymbols::java_lang_InternalError(), CHECK); 423 } 424 425 bool Threads::initialize_compilation(TRAPS) { 426 // initialize compiler(s) 427 bool force_JVMCI_initialization = false; 428 429 #if defined(COMPILER1) || COMPILER2_OR_JVMCI 430 bool init_compilation = true; 431 #if INCLUDE_JVMCI 432 if (EnableJVMCI) { 433 // Initialize JVMCI eagerly when it is explicitly requested. 434 // Or when JVMCILibDumpJNIConfig or JVMCIPrintProperties is enabled. 435 force_JVMCI_initialization = EagerJVMCI || JVMCIPrintProperties || JVMCILibDumpJNIConfig; 436 if (!force_JVMCI_initialization && UseJVMCICompiler && !UseJVMCINativeLibrary && (!UseInterpreter || !BackgroundCompilation)) { 437 // Force initialization of jarjvmci otherwise requests for blocking 438 // compilations will not actually block until jarjvmci is initialized. 439 force_JVMCI_initialization = true; 440 } 441 if (JVMCIPrintProperties || JVMCILibDumpJNIConfig) { 442 // Both JVMCILibDumpJNIConfig and JVMCIPrintProperties exit the VM 443 // so compilation should be disabled. This prevents dumping or 444 // printing from happening more than once. 445 init_compilation = false; 446 } 447 } 448 #endif 449 if (init_compilation) { 450 CompileBroker::compilation_init(CHECK_false); 451 } 452 #endif 453 454 return force_JVMCI_initialization; 455 } 456 457 void Threads::initialize_jsr292_core_classes(TRAPS) { 458 TraceTime timer("Initialize java.lang.invoke classes", TRACETIME_LOG(Info, startuptime)); 459 460 initialize_class(vmSymbols::java_lang_invoke_MethodHandle(), CHECK); 461 initialize_class(vmSymbols::java_lang_invoke_ResolvedMethodName(), CHECK); 462 initialize_class(vmSymbols::java_lang_invoke_MemberName(), CHECK); 463 initialize_class(vmSymbols::java_lang_invoke_MethodHandleNatives(), CHECK); 464 465 if (UseSharedSpaces) { 466 HeapShared::initialize_java_lang_invoke(CHECK); 467 } 468 } 469 470 // One-shot PeriodicTask subclass for reading the release file 471 class ReadReleaseFileTask : public PeriodicTask { 472 public: 473 ReadReleaseFileTask() : PeriodicTask(100) {} 474 475 virtual void task() { 476 os::read_image_release_file(); 477 478 // Reclaim our storage and disenroll ourself. 479 delete this; 480 } 481 }; 482 483 jint Threads::create_vm(JavaVMInitArgs* args, bool* canTryAgain) { 484 extern void JDK_Version_init(); 485 486 // Preinitialize version info. 487 VM_Version::early_initialize(); 488 489 // Check version 490 if (!is_supported_jni_version(args->version)) return JNI_EVERSION; 491 492 // Initialize library-based TLS 493 ThreadLocalStorage::init(); 494 495 // Initialize the output stream module 496 ostream_init(); 497 498 // Process java launcher properties. 499 Arguments::process_sun_java_launcher_properties(args); 500 501 // Initialize the os module 502 os::init(); 503 504 // Initialize memory pools 505 Arena::initialize_chunk_pool(); 506 507 MACOS_AARCH64_ONLY(os::current_thread_enable_wx(WXWrite)); 508 509 // Record VM creation timing statistics 510 TraceVmCreationTime create_vm_timer; 511 create_vm_timer.start(); 512 513 // Initialize system properties. 514 Arguments::init_system_properties(); 515 516 // So that JDK version can be used as a discriminator when parsing arguments 517 JDK_Version_init(); 518 519 // Update/Initialize System properties after JDK version number is known 520 Arguments::init_version_specific_system_properties(); 521 522 // Make sure to initialize log configuration *before* parsing arguments 523 LogConfiguration::initialize(create_vm_timer.begin_time()); 524 525 // Parse arguments 526 // Note: this internally calls os::init_container_support() 527 jint parse_result = Arguments::parse(args); 528 if (parse_result != JNI_OK) return parse_result; 529 530 // Initialize NMT right after argument parsing to keep the pre-NMT-init window small. 531 MemTracker::initialize(); 532 533 os::init_before_ergo(); 534 535 jint ergo_result = Arguments::apply_ergo(); 536 if (ergo_result != JNI_OK) return ergo_result; 537 538 // Final check of all ranges after ergonomics which may change values. 539 if (!JVMFlagLimit::check_all_ranges()) { 540 return JNI_EINVAL; 541 } 542 543 // Final check of all 'AfterErgo' constraints after ergonomics which may change values. 544 bool constraint_result = JVMFlagLimit::check_all_constraints(JVMFlagConstraintPhase::AfterErgo); 545 if (!constraint_result) { 546 return JNI_EINVAL; 547 } 548 549 if (PauseAtStartup) { 550 os::pause(); 551 } 552 553 HOTSPOT_VM_INIT_BEGIN(); 554 555 // Timing (must come after argument parsing) 556 TraceTime timer("Create VM", TRACETIME_LOG(Info, startuptime)); 557 558 // Initialize the os module after parsing the args 559 jint os_init_2_result = os::init_2(); 560 if (os_init_2_result != JNI_OK) return os_init_2_result; 561 562 #ifdef CAN_SHOW_REGISTERS_ON_ASSERT 563 // Initialize assert poison page mechanism. 564 if (ShowRegistersOnAssert) { 565 initialize_assert_poison(); 566 } 567 #endif // CAN_SHOW_REGISTERS_ON_ASSERT 568 569 SafepointMechanism::initialize(); 570 571 jint adjust_after_os_result = Arguments::adjust_after_os(); 572 if (adjust_after_os_result != JNI_OK) return adjust_after_os_result; 573 574 // Initialize output stream logging 575 ostream_init_log(); 576 577 // Launch -agentlib/-agentpath and converted -Xrun agents 578 JvmtiAgentList::load_agents(); 579 580 // Initialize Threads state 581 _number_of_threads = 0; 582 _number_of_non_daemon_threads = 0; 583 584 // Initialize global data structures and create system classes in heap 585 vm_init_globals(); 586 587 #if INCLUDE_JVMCI 588 if (JVMCICounterSize > 0) { 589 JavaThread::_jvmci_old_thread_counters = NEW_C_HEAP_ARRAY(jlong, JVMCICounterSize, mtJVMCI); 590 memset(JavaThread::_jvmci_old_thread_counters, 0, sizeof(jlong) * JVMCICounterSize); 591 } else { 592 JavaThread::_jvmci_old_thread_counters = nullptr; 593 } 594 #endif // INCLUDE_JVMCI 595 596 // Initialize OopStorage for threadObj 597 JavaThread::_thread_oop_storage = OopStorageSet::create_strong("Thread OopStorage", mtThread); 598 599 // Attach the main thread to this os thread 600 JavaThread* main_thread = new JavaThread(); 601 main_thread->set_thread_state(_thread_in_vm); 602 main_thread->initialize_thread_current(); 603 // Once mutexes and main_thread are ready, we can use NmtVirtualMemoryLocker. 604 MemTracker::NmtVirtualMemoryLocker::set_safe_to_use(); 605 // must do this before set_active_handles 606 main_thread->record_stack_base_and_size(); 607 main_thread->register_thread_stack_with_NMT(); 608 main_thread->set_active_handles(JNIHandleBlock::allocate_block()); 609 MACOS_AARCH64_ONLY(main_thread->init_wx()); 610 611 MutexLockerImpl::init_counters(); // depends on mutex_init(), perfMemory_init(), and Thread::initialize_thread_current(). 612 613 // Set the _monitor_owner_id now since we will run Java code before the Thread instance 614 // is even created. The same value will be assigned to the Thread instance on init. 615 main_thread->set_monitor_owner_id(ThreadIdentifier::next()); 616 617 if (!Thread::set_as_starting_thread(main_thread)) { 618 vm_shutdown_during_initialization( 619 "Failed necessary internal allocation. Out of swap space"); 620 main_thread->smr_delete(); 621 *canTryAgain = false; // don't let caller call JNI_CreateJavaVM again 622 return JNI_ENOMEM; 623 } 624 625 JFR_ONLY(Jfr::initialize_main_thread(main_thread);) 626 627 // Enable guard page *after* os::create_main_thread(), otherwise it would 628 // crash Linux VM, see notes in os_linux.cpp. 629 main_thread->stack_overflow_state()->create_stack_guard_pages(); 630 631 // Initialize Java-Level synchronization subsystem 632 ObjectMonitor::Initialize(); 633 ObjectSynchronizer::initialize(); 634 635 Deoptimization::init_counters(); 636 VMThread::init_counters(); 637 638 // Initialize global modules 639 jint status = init_globals(); 640 if (status != JNI_OK) { 641 main_thread->smr_delete(); 642 *canTryAgain = false; // don't let caller call JNI_CreateJavaVM again 643 return status; 644 } 645 if (xtty != nullptr) 646 xtty->elem("vm_main_thread thread='%zu'", 647 (uintx) main_thread->osthread()->thread_id()); 648 649 // Have the WatcherThread read the release file in the background. 650 ReadReleaseFileTask* read_task = new ReadReleaseFileTask(); 651 read_task->enroll(); 652 653 // Create WatcherThread as soon as we can since we need it in case 654 // of hangs during error reporting. 655 WatcherThread::start(); 656 657 // Add main_thread to threads list to finish barrier setup with 658 // on_thread_attach. Should be before starting to build Java objects in 659 // init_globals2, which invokes barriers. 660 { 661 MutexLocker mu(Threads_lock); 662 Threads::add(main_thread); 663 } 664 665 status = init_globals2(); 666 if (status != JNI_OK) { 667 Threads::remove(main_thread, false); 668 // It is possible that we managed to fully initialize Universe but have then 669 // failed by throwing an exception. In that case our caller JNI_CreateJavaVM 670 // will want to report it, so we can't delete the main thread. 671 if (!main_thread->has_pending_exception()) { 672 main_thread->smr_delete(); 673 } 674 *canTryAgain = false; // don't let caller call JNI_CreateJavaVM again 675 return status; 676 } 677 678 ObjectMonitor::Initialize2(); 679 680 JFR_ONLY(Jfr::on_create_vm_1();) 681 682 // Should be done after the heap is fully created 683 main_thread->cache_global_variables(); 684 685 // Any JVMTI raw monitors entered in onload will transition into 686 // real raw monitor. VM is setup enough here for raw monitor enter. 687 JvmtiExport::transition_pending_onload_raw_monitors(); 688 689 // Create the VMThread 690 { TraceTime timer("Start VMThread", TRACETIME_LOG(Info, startuptime)); 691 692 VMThread::create(); 693 VMThread* vmthread = VMThread::vm_thread(); 694 695 if (!os::create_thread(vmthread, os::vm_thread)) { 696 vm_exit_during_initialization("Cannot create VM thread. " 697 "Out of system resources."); 698 } 699 700 // Wait for the VM thread to become ready, and VMThread::run to initialize 701 // Monitors can have spurious returns, must always check another state flag 702 { 703 MonitorLocker ml(Notify_lock); 704 os::start_thread(vmthread); 705 while (!vmthread->is_running()) { 706 ml.wait(); 707 } 708 } 709 } 710 711 assert(Universe::is_fully_initialized(), "not initialized"); 712 if (VerifyDuringStartup) { 713 // Make sure we're starting with a clean slate. 714 VM_Verify verify_op; 715 VMThread::execute(&verify_op); 716 } 717 718 // We need this to update the java.vm.info property in case any flags used 719 // to initially define it have been changed. This is needed for both CDS 720 // since UseSharedSpaces may be changed after java.vm.info 721 // is initially computed. See Abstract_VM_Version::vm_info_string(). 722 // This update must happen before we initialize the java classes, but 723 // after any initialization logic that might modify the flags. 724 Arguments::update_vm_info_property(VM_Version::vm_info_string()); 725 726 JavaThread* THREAD = JavaThread::current(); // For exception macros. 727 HandleMark hm(THREAD); 728 729 // Always call even when there are not JVMTI environments yet, since environments 730 // may be attached late and JVMTI must track phases of VM execution 731 JvmtiExport::enter_early_start_phase(); 732 733 // Notify JVMTI agents that VM has started (JNI is up) - nop if no agents. 734 JvmtiExport::post_early_vm_start(); 735 736 // Launch -Xrun agents early if EagerXrunInit is set 737 if (EagerXrunInit) { 738 JvmtiAgentList::load_xrun_agents(); 739 } 740 741 initialize_java_lang_classes(main_thread, CHECK_JNI_ERR); 742 743 quicken_jni_functions(); 744 745 // No more stub generation allowed after that point. 746 StubCodeDesc::freeze(); 747 748 // Set flag that basic initialization has completed. Used by exceptions and various 749 // debug stuff, that does not work until all basic classes have been initialized. 750 set_init_completed(); 751 752 LogConfiguration::post_initialize(); 753 Metaspace::post_initialize(); 754 MutexLockerImpl::post_initialize(); 755 756 HOTSPOT_VM_INIT_END(); 757 758 // record VM initialization completion time 759 #if INCLUDE_MANAGEMENT 760 Management::record_vm_init_completed(); 761 #endif // INCLUDE_MANAGEMENT 762 763 log_info(os)("Initialized VM with process ID %d", os::current_process_id()); 764 765 if (!FLAG_IS_DEFAULT(CreateCoredumpOnCrash) && CreateCoredumpOnCrash) { 766 char buffer[2*JVM_MAXPATHLEN]; 767 os::check_core_dump_prerequisites(buffer, sizeof(buffer), true); 768 } 769 770 // Signal Dispatcher needs to be started before VMInit event is posted 771 os::initialize_jdk_signal_support(CHECK_JNI_ERR); 772 773 // Start Attach Listener if +StartAttachListener or it can't be started lazily 774 if (!DisableAttachMechanism) { 775 AttachListener::vm_start(); 776 if (StartAttachListener || AttachListener::init_at_startup()) { 777 AttachListener::init(); 778 } 779 } 780 781 // Launch -Xrun agents if EagerXrunInit is not set. 782 if (!EagerXrunInit) { 783 JvmtiAgentList::load_xrun_agents(); 784 } 785 786 Arena::start_chunk_pool_cleaner_task(); 787 788 // Start the service thread 789 // The service thread enqueues JVMTI deferred events and does various hashtable 790 // and other cleanups. Needs to start before the compilers start posting events. 791 ServiceThread::initialize(); 792 793 // Start the monitor deflation thread: 794 MonitorDeflationThread::initialize(); 795 796 #if INCLUDE_CDS 797 // Start the method sampler 798 MethodProfiler::initialize(); 799 #endif 800 801 bool force_JVMCI_initialization = initialize_compilation(CHECK_JNI_ERR); 802 803 if (CDSConfig::is_using_aot_linked_classes()) { 804 SystemDictionary::restore_archived_method_handle_intrinsics(); 805 AOTLinkedClassBulkLoader::finish_loading_javabase_classes(CHECK_JNI_ERR); 806 } 807 808 // Start string deduplication thread if requested. 809 if (StringDedup::is_enabled()) { 810 StringDedup::start(); 811 } 812 813 // Pre-initialize some JSR292 core classes to avoid deadlock during class loading. 814 // It is done after compilers are initialized, because otherwise compilations of 815 // signature polymorphic MH intrinsics can be missed 816 // (see SystemDictionary::find_method_handle_intrinsic). 817 initialize_jsr292_core_classes(CHECK_JNI_ERR); 818 819 // This will initialize the module system. Only java.base classes can be 820 // loaded until phase 2 completes 821 call_initPhase2(CHECK_JNI_ERR); 822 823 if (CDSConfig::is_using_aot_linked_classes() && !CDSConfig::is_dumping_final_static_archive()) { 824 AOTLinkedClassBulkLoader::load_non_javabase_classes(THREAD); 825 } 826 #ifndef PRODUCT 827 HeapShared::initialize_test_class_from_archive(THREAD); 828 #endif 829 830 JFR_ONLY(Jfr::on_create_vm_2();) 831 832 // Always call even when there are not JVMTI environments yet, since environments 833 // may be attached late and JVMTI must track phases of VM execution 834 JvmtiExport::enter_start_phase(); 835 836 // Notify JVMTI agents that VM has started (JNI is up) - nop if no agents. 837 JvmtiExport::post_vm_start(); 838 839 // Final system initialization including security manager and system class loader 840 call_initPhase3(CHECK_JNI_ERR); 841 842 // cache the system and platform class loaders 843 SystemDictionary::compute_java_loaders(CHECK_JNI_ERR); 844 845 // Initiate replay training processing once preloading is over. 846 CompileBroker::init_training_replay(); 847 848 AOTLinkedClassBulkLoader::replay_training_at_init_for_preloaded_classes(CHECK_JNI_ERR); 849 850 if (Continuations::enabled()) { 851 // Initialize Continuation class now so that failure to create enterSpecial/doYield 852 // special nmethods due to limited CodeCache size can be treated as a fatal error at 853 // startup with the proper message that CodeCache size is too small. 854 initialize_class(vmSymbols::jdk_internal_vm_Continuation(), CHECK_JNI_ERR); 855 } 856 857 #if INCLUDE_CDS 858 if (PrecompileCode) { 859 Precompiler::compile_cached_code(CHECK_JNI_ERR); 860 if (PrecompileOnlyAndExit) { 861 AOTCodeCache::close(); 862 log_vm_init_stats(); 863 vm_direct_exit(0, "Code precompiation is over"); 864 } 865 } 866 #endif 867 868 #if defined(COMPILER2) 869 // Pre-load cached compiled methods 870 AOTCodeCache::preload_code(CHECK_JNI_ERR); 871 #endif 872 873 if (NativeHeapTrimmer::enabled()) { 874 NativeHeapTrimmer::initialize(); 875 } 876 877 // Always call even when there are not JVMTI environments yet, since environments 878 // may be attached late and JVMTI must track phases of VM execution 879 JvmtiExport::enter_live_phase(); 880 881 // Make perfmemory accessible 882 PerfMemory::set_accessible(true); 883 884 // Notify JVMTI agents that VM initialization is complete - nop if no agents. 885 JvmtiExport::post_vm_initialized(); 886 887 #if INCLUDE_JVMCI 888 if (force_JVMCI_initialization) { 889 JVMCI::initialize_compiler_in_create_vm(CHECK_JNI_ERR); 890 } 891 #endif 892 893 JFR_ONLY(Jfr::on_create_vm_3();) 894 895 #if INCLUDE_MANAGEMENT 896 Management::initialize(THREAD); 897 898 if (HAS_PENDING_EXCEPTION) { 899 // management agent fails to start possibly due to 900 // configuration problem and is responsible for printing 901 // stack trace if appropriate. Simply exit VM. 902 vm_exit(1); 903 } 904 #endif // INCLUDE_MANAGEMENT 905 906 if (UsePerfData) PerfDataManager::create_misc_perfdata(); 907 if (CheckJNICalls) JniPeriodicChecker::engage(); 908 909 call_postVMInitHook(THREAD); 910 // The Java side of PostVMInitHook.run must deal with all 911 // exceptions and provide means of diagnosis. 912 if (HAS_PENDING_EXCEPTION) { 913 CLEAR_PENDING_EXCEPTION; 914 } 915 916 // Let WatcherThread run all registered periodic tasks now. 917 // NOTE: All PeriodicTasks should be registered by now. If they 918 // aren't, late joiners might appear to start slowly (we might 919 // take a while to process their first tick). 920 WatcherThread::run_all_tasks(); 921 922 create_vm_timer.end(); 923 #ifdef ASSERT 924 _vm_complete = true; 925 #endif 926 927 if (CDSConfig::is_dumping_classic_static_archive()) { 928 // Classic -Xshare:dump, aka "old workflow" 929 MetaspaceShared::preload_and_dump(CHECK_JNI_ERR); 930 } else if (CDSConfig::is_dumping_final_static_archive()) { 931 if (CDSConfig::is_experimental_leyden_workflow()) { 932 // TODO: copy the verification and loader constraints from preimage to final image 933 // TODO: load archived classes for custom loaders as well. 934 log_info(cds)("Dumping final image of CacheDataStore %s", CacheDataStore); 935 MetaspaceShared::preload_and_dump(CHECK_JNI_ERR); 936 vm_direct_exit(0, "CacheDataStore dumping is complete"); 937 } else { 938 tty->print_cr("Reading AOTConfiguration %s and writing AOTCache %s", AOTConfiguration, AOTCache); 939 MetaspaceShared::preload_and_dump(CHECK_JNI_ERR); 940 } 941 } 942 943 log_info(init)("At VM initialization completion:"); 944 log_vm_init_stats(); 945 946 if (UsePerfData) { 947 if (ProfileVMLocks) { 948 main_thread->set_profile_vm_locks(true); 949 } 950 if (ProfileVMCalls) { 951 main_thread->set_profile_vm_calls(true); 952 } 953 if (ProfileRuntimeCalls) { 954 main_thread->set_profile_rt_calls(true); 955 } 956 if (ProfileVMOps) { 957 main_thread->set_profile_vm_ops(true); 958 } 959 } 960 961 return JNI_OK; 962 } 963 964 // Threads::destroy_vm() is normally called from jni_DestroyJavaVM() when 965 // the program falls off the end of main(). Another VM exit path is through 966 // vm_exit(), when the program calls System.exit() to return a value, or when 967 // there is a serious error in VM. 968 // These two separate shutdown paths are not exactly the same, but they share 969 // Shutdown.shutdown() at Java level and before_exit() and VM_Exit op at VM level. 970 // 971 // Shutdown sequence: 972 // + Shutdown native memory tracking if it is on 973 // + Wait until we are the last non-daemon thread to execute 974 // <-- every thing is still working at this moment --> 975 // + Call java.lang.Shutdown.shutdown(), which will invoke Java level 976 // shutdown hooks 977 // + Call before_exit(), prepare for VM exit 978 // > run VM level shutdown hooks (they are registered through JVM_OnExit(), 979 // currently the only user of this mechanism is File.deleteOnExit()) 980 // > stop watcher thread, 981 // post thread end and vm death events to JVMTI, 982 // stop signal thread 983 // + Call JavaThread::exit(), it will: 984 // > release JNI handle blocks, remove stack guard pages 985 // > remove this thread from Threads list 986 // <-- no more Java code from this thread after this point --> 987 // + Stop VM thread, it will bring the remaining VM to a safepoint and stop 988 // the compiler threads at safepoint 989 // <-- do not use anything that could get blocked by Safepoint --> 990 // + Disable tracing at JNI/JVM barriers 991 // + Set _vm_exited flag for threads that are still running native code 992 // + Call exit_globals() 993 // > deletes tty 994 // > deletes PerfMemory resources 995 // + Delete this thread 996 // + Return to caller 997 998 void Threads::destroy_vm() { 999 JavaThread* thread = JavaThread::current(); 1000 1001 #ifdef ASSERT 1002 _vm_complete = false; 1003 #endif 1004 // Wait until we are the last non-daemon thread to execute, or 1005 // if we are a daemon then wait until the last non-daemon thread has 1006 // executed. 1007 bool daemon = java_lang_Thread::is_daemon(thread->threadObj()); 1008 int expected = daemon ? 0 : 1; 1009 { 1010 MonitorLocker nu(Threads_lock); 1011 while (Threads::number_of_non_daemon_threads() > expected) 1012 // This wait should make safepoint checks, wait without a timeout. 1013 nu.wait(0); 1014 } 1015 1016 EventShutdown e; 1017 if (e.should_commit()) { 1018 e.set_reason("No remaining non-daemon Java threads"); 1019 e.commit(); 1020 } 1021 1022 // Hang forever on exit if we are reporting an error. 1023 if (ShowMessageBoxOnError && VMError::is_error_reported()) { 1024 os::infinite_sleep(); 1025 } 1026 os::wait_for_keypress_at_exit(); 1027 1028 // run Java level shutdown hooks 1029 thread->invoke_shutdown_hooks(); 1030 1031 before_exit(thread); 1032 1033 thread->exit(true); 1034 1035 // We are no longer on the main thread list but could still be in a 1036 // secondary list where another thread may try to interact with us. 1037 // So wait until all such interactions are complete before we bring 1038 // the VM to the termination safepoint. Normally this would be done 1039 // using thread->smr_delete() below where we delete the thread, but 1040 // we can't call that after the termination safepoint is active as 1041 // we will deadlock on the Threads_lock. Once all interactions are 1042 // complete it is safe to directly delete the thread at any time. 1043 ThreadsSMRSupport::wait_until_not_protected(thread); 1044 1045 // Stop VM thread. 1046 { 1047 // 4945125 The vm thread comes to a safepoint during exit. 1048 // GC vm_operations can get caught at the safepoint, and the 1049 // heap is unparseable if they are caught. Grab the Heap_lock 1050 // to prevent this. The GC vm_operations will not be able to 1051 // queue until after the vm thread is dead. After this point, 1052 // we'll never emerge out of the safepoint before the VM exits. 1053 // Assert that the thread is terminated so that acquiring the 1054 // Heap_lock doesn't cause the terminated thread to participate in 1055 // the safepoint protocol. 1056 1057 assert(thread->is_terminated(), "must be terminated here"); 1058 MutexLocker ml(Heap_lock); 1059 1060 VMThread::wait_for_vm_thread_exit(); 1061 assert(SafepointSynchronize::is_at_safepoint(), "VM thread should exit at Safepoint"); 1062 VMThread::destroy(); 1063 } 1064 1065 // Now, all Java threads are gone except daemon threads. Daemon threads 1066 // running Java code or in VM are stopped by the Safepoint. However, 1067 // daemon threads executing native code are still running. But they 1068 // will be stopped at native=>Java/VM barriers. Note that we can't 1069 // simply kill or suspend them, as it is inherently deadlock-prone. 1070 1071 VM_Exit::set_vm_exited(); 1072 1073 // Clean up ideal graph printers after the VMThread has started 1074 // the final safepoint which will block all the Compiler threads. 1075 // Note that this Thread has already logically exited so the 1076 // clean_up() function's use of a JavaThreadIteratorWithHandle 1077 // would be a problem except set_vm_exited() has remembered the 1078 // shutdown thread which is granted a policy exception. 1079 #if defined(COMPILER2) && !defined(PRODUCT) 1080 IdealGraphPrinter::clean_up(); 1081 #endif 1082 1083 notify_vm_shutdown(); 1084 1085 // exit_globals() will delete tty 1086 exit_globals(); 1087 1088 // Deleting the shutdown thread here is safe. See comment on 1089 // wait_until_not_protected() above. 1090 delete thread; 1091 1092 #if INCLUDE_JVMCI 1093 if (JVMCICounterSize > 0) { 1094 FREE_C_HEAP_ARRAY(jlong, JavaThread::_jvmci_old_thread_counters); 1095 } 1096 #endif 1097 1098 LogConfiguration::finalize(); 1099 } 1100 1101 1102 jboolean Threads::is_supported_jni_version_including_1_1(jint version) { 1103 if (version == JNI_VERSION_1_1) return JNI_TRUE; 1104 return is_supported_jni_version(version); 1105 } 1106 1107 1108 jboolean Threads::is_supported_jni_version(jint version) { 1109 if (version == JNI_VERSION_1_2) return JNI_TRUE; 1110 if (version == JNI_VERSION_1_4) return JNI_TRUE; 1111 if (version == JNI_VERSION_1_6) return JNI_TRUE; 1112 if (version == JNI_VERSION_1_8) return JNI_TRUE; 1113 if (version == JNI_VERSION_9) return JNI_TRUE; 1114 if (version == JNI_VERSION_10) return JNI_TRUE; 1115 if (version == JNI_VERSION_19) return JNI_TRUE; 1116 if (version == JNI_VERSION_20) return JNI_TRUE; 1117 if (version == JNI_VERSION_21) return JNI_TRUE; 1118 if (version == JNI_VERSION_24) return JNI_TRUE; 1119 return JNI_FALSE; 1120 } 1121 1122 void Threads::add(JavaThread* p, bool force_daemon) { 1123 // The threads lock must be owned at this point 1124 assert(Threads_lock->owned_by_self(), "must have threads lock"); 1125 assert(p->monitor_owner_id() != 0, "should be set"); 1126 1127 BarrierSet::barrier_set()->on_thread_attach(p); 1128 1129 // Once a JavaThread is added to the Threads list, smr_delete() has 1130 // to be used to delete it. Otherwise we can just delete it directly. 1131 p->set_on_thread_list(); 1132 1133 _number_of_threads++; 1134 oop threadObj = p->threadObj(); 1135 bool daemon = true; 1136 // Bootstrapping problem: threadObj can be null for initial 1137 // JavaThread (or for threads attached via JNI) 1138 if (!force_daemon && 1139 (threadObj == nullptr || !java_lang_Thread::is_daemon(threadObj))) { 1140 _number_of_non_daemon_threads++; 1141 daemon = false; 1142 } 1143 1144 ThreadService::add_thread(p, daemon); 1145 1146 // Maintain fast thread list 1147 ThreadsSMRSupport::add_thread(p); 1148 1149 // Increase the ObjectMonitor ceiling for the new thread. 1150 ObjectSynchronizer::inc_in_use_list_ceiling(); 1151 1152 // Possible GC point. 1153 Events::log(Thread::current(), "Thread added: " INTPTR_FORMAT, p2i(p)); 1154 1155 // Make new thread known to active EscapeBarrier 1156 EscapeBarrier::thread_added(p); 1157 } 1158 1159 void Threads::remove(JavaThread* p, bool is_daemon) { 1160 // Extra scope needed for Thread_lock, so we can check 1161 // that we do not remove thread without safepoint code notice 1162 { 1163 ConditionalMutexLocker throttle_ml(ThreadsLockThrottle_lock, UseThreadsLockThrottleLock); 1164 MonitorLocker ml(Threads_lock); 1165 1166 if (ThreadIdTable::is_initialized()) { 1167 // This cleanup must be done before the current thread's GC barrier 1168 // is detached since we need to touch the threadObj oop. 1169 jlong tid = SharedRuntime::get_java_tid(p); 1170 ThreadIdTable::remove_thread(tid); 1171 } 1172 1173 // BarrierSet state must be destroyed after the last thread transition 1174 // before the thread terminates. Thread transitions result in calls to 1175 // StackWatermarkSet::on_safepoint(), which performs GC processing, 1176 // requiring the GC state to be alive. 1177 BarrierSet::barrier_set()->on_thread_detach(p); 1178 if (p->is_exiting()) { 1179 // If we got here via JavaThread::exit(), then we remember that the 1180 // thread's GC barrier has been detached. We don't do this when we get 1181 // here from another path, e.g., cleanup_failed_attach_current_thread(). 1182 p->set_terminated(JavaThread::_thread_gc_barrier_detached); 1183 } 1184 1185 assert(ThreadsSMRSupport::get_java_thread_list()->includes(p), "p must be present"); 1186 1187 // Maintain fast thread list 1188 ThreadsSMRSupport::remove_thread(p); 1189 1190 _number_of_threads--; 1191 if (!is_daemon) { 1192 _number_of_non_daemon_threads--; 1193 1194 // If this is the last non-daemon thread then we need to do 1195 // a notify on the Threads_lock so a thread waiting 1196 // on destroy_vm will wake up. But that thread could be a daemon 1197 // or non-daemon, so we notify for both the 0 and 1 case. 1198 if (number_of_non_daemon_threads() <= 1) { 1199 ml.notify_all(); 1200 } 1201 } 1202 ThreadService::remove_thread(p, is_daemon); 1203 1204 // Make sure that safepoint code disregard this thread. This is needed since 1205 // the thread might mess around with locks after this point. This can cause it 1206 // to do callbacks into the safepoint code. However, the safepoint code is not aware 1207 // of this thread since it is removed from the queue. 1208 p->set_terminated(JavaThread::_thread_terminated); 1209 1210 // Notify threads waiting in EscapeBarriers 1211 EscapeBarrier::thread_removed(p); 1212 } // unlock Threads_lock and ThreadsLockThrottle_lock 1213 1214 // Reduce the ObjectMonitor ceiling for the exiting thread. 1215 ObjectSynchronizer::dec_in_use_list_ceiling(); 1216 1217 // Since Events::log uses a lock, we grab it outside the Threads_lock 1218 Events::log(Thread::current(), "Thread exited: " INTPTR_FORMAT, p2i(p)); 1219 } 1220 1221 // Operations on the Threads list for GC. These are not explicitly locked, 1222 // but the garbage collector must provide a safe context for them to run. 1223 // In particular, these things should never be called when the Threads_lock 1224 // is held by some other thread. (Note: the Safepoint abstraction also 1225 // uses the Threads_lock to guarantee this property. It also makes sure that 1226 // all threads gets blocked when exiting or starting). 1227 1228 void Threads::oops_do(OopClosure* f, NMethodClosure* cf) { 1229 ALL_JAVA_THREADS(p) { 1230 p->oops_do(f, cf); 1231 } 1232 VMThread::vm_thread()->oops_do(f, cf); 1233 } 1234 1235 void Threads::change_thread_claim_token() { 1236 if (++_thread_claim_token == 0) { 1237 // On overflow of the token counter, there is a risk of future 1238 // collisions between a new global token value and a stale token 1239 // for a thread, because not all iterations visit all threads. 1240 // (Though it's pretty much a theoretical concern for non-trivial 1241 // token counter sizes.) To deal with the possibility, reset all 1242 // the thread tokens to zero on global token overflow. 1243 struct ResetClaims : public ThreadClosure { 1244 virtual void do_thread(Thread* t) { 1245 t->claim_threads_do(false, 0); 1246 } 1247 } reset_claims; 1248 Threads::threads_do(&reset_claims); 1249 // On overflow, update the global token to non-zero, to 1250 // avoid the special "never claimed" initial thread value. 1251 _thread_claim_token = 1; 1252 } 1253 } 1254 1255 #ifdef ASSERT 1256 static void assert_thread_claimed(const char* kind, Thread* t, uintx expected) { 1257 const uintx token = t->threads_do_token(); 1258 assert(token == expected, 1259 "%s " PTR_FORMAT " has incorrect value %zu != %zu", 1260 kind, p2i(t), token, expected); 1261 } 1262 1263 void Threads::assert_all_threads_claimed() { 1264 ALL_JAVA_THREADS(p) { 1265 assert_thread_claimed("JavaThread", p, _thread_claim_token); 1266 } 1267 1268 struct NJTClaimedVerifierClosure : public ThreadClosure { 1269 uintx _thread_claim_token; 1270 1271 NJTClaimedVerifierClosure(uintx thread_claim_token) : ThreadClosure(), _thread_claim_token(thread_claim_token) { } 1272 1273 virtual void do_thread(Thread* thread) override { 1274 assert_thread_claimed("Non-JavaThread", VMThread::vm_thread(), _thread_claim_token); 1275 } 1276 } tc(_thread_claim_token); 1277 1278 non_java_threads_do(&tc); 1279 } 1280 #endif // ASSERT 1281 1282 class ParallelOopsDoThreadClosure : public ThreadClosure { 1283 private: 1284 OopClosure* _f; 1285 NMethodClosure* _cf; 1286 public: 1287 ParallelOopsDoThreadClosure(OopClosure* f, NMethodClosure* cf) : _f(f), _cf(cf) {} 1288 void do_thread(Thread* t) { 1289 t->oops_do(_f, _cf); 1290 } 1291 }; 1292 1293 void Threads::possibly_parallel_oops_do(bool is_par, OopClosure* f, NMethodClosure* cf) { 1294 ParallelOopsDoThreadClosure tc(f, cf); 1295 possibly_parallel_threads_do(is_par, &tc); 1296 } 1297 1298 void Threads::metadata_do(MetadataClosure* f) { 1299 ALL_JAVA_THREADS(p) { 1300 p->metadata_do(f); 1301 } 1302 } 1303 1304 class ThreadHandlesClosure : public ThreadClosure { 1305 void (*_f)(Metadata*); 1306 public: 1307 ThreadHandlesClosure(void f(Metadata*)) : _f(f) {} 1308 virtual void do_thread(Thread* thread) { 1309 thread->metadata_handles_do(_f); 1310 } 1311 }; 1312 1313 void Threads::metadata_handles_do(void f(Metadata*)) { 1314 // Only walk the Handles in Thread. 1315 ThreadHandlesClosure handles_closure(f); 1316 threads_do(&handles_closure); 1317 } 1318 1319 #if INCLUDE_JVMTI 1320 // Get Java threads that are waiting to enter or re-enter the specified monitor. 1321 // Java threads that are executing mounted virtual threads are not included. 1322 GrowableArray<JavaThread*>* Threads::get_pending_threads(ThreadsList * t_list, 1323 int count, 1324 address monitor) { 1325 assert(Thread::current()->is_VM_thread(), "Must be the VM thread"); 1326 GrowableArray<JavaThread*>* result = new GrowableArray<JavaThread*>(count); 1327 1328 int i = 0; 1329 for (JavaThread* p : *t_list) { 1330 if (!p->can_call_java()) continue; 1331 1332 oop thread_oop = JvmtiEnvBase::get_vthread_or_thread_oop(p); 1333 if (thread_oop->is_a(vmClasses::BaseVirtualThread_klass())) { 1334 continue; 1335 } 1336 // The first stage of async deflation does not affect any field 1337 // used by this comparison so the ObjectMonitor* is usable here. 1338 address pending = (address)p->current_pending_monitor(); 1339 address waiting = (address)p->current_waiting_monitor(); 1340 // do not include virtual threads to the list 1341 jint state = JvmtiEnvBase::get_thread_state(thread_oop, p); 1342 if (pending == monitor || (waiting == monitor && 1343 (state & JVMTI_THREAD_STATE_BLOCKED_ON_MONITOR_ENTER)) 1344 ) { // found a match 1345 if (i < count) result->append(p); // save the first count matches 1346 i++; 1347 } 1348 } 1349 1350 return result; 1351 } 1352 #endif // INCLUDE_JVMTI 1353 1354 JavaThread *Threads::owning_thread_from_stacklock(ThreadsList * t_list, address basicLock) { 1355 assert(LockingMode == LM_LEGACY, "Not with new lightweight locking"); 1356 1357 JavaThread* the_owner = nullptr; 1358 for (JavaThread* q : *t_list) { 1359 if (q->is_lock_owned(basicLock)) { 1360 the_owner = q; 1361 break; 1362 } 1363 } 1364 return the_owner; 1365 } 1366 1367 JavaThread* Threads::owning_thread_from_object(ThreadsList * t_list, oop obj) { 1368 assert(LockingMode == LM_LIGHTWEIGHT, "Only with new lightweight locking"); 1369 for (JavaThread* q : *t_list) { 1370 // Need to start processing before accessing oops in the thread. 1371 StackWatermark* watermark = StackWatermarkSet::get(q, StackWatermarkKind::gc); 1372 if (watermark != nullptr) { 1373 watermark->start_processing(); 1374 } 1375 1376 if (q->lock_stack().contains(obj)) { 1377 return q; 1378 } 1379 } 1380 return nullptr; 1381 } 1382 1383 JavaThread* Threads::owning_thread_from_monitor(ThreadsList* t_list, ObjectMonitor* monitor) { 1384 if (monitor->has_anonymous_owner()) { 1385 if (LockingMode == LM_LIGHTWEIGHT) { 1386 return owning_thread_from_object(t_list, monitor->object()); 1387 } else { 1388 assert(LockingMode == LM_LEGACY, "invariant"); 1389 return owning_thread_from_stacklock(t_list, (address)monitor->stack_locker()); 1390 } 1391 } else { 1392 JavaThread* the_owner = nullptr; 1393 for (JavaThread* q : *t_list) { 1394 if (monitor->has_owner(q)) { 1395 the_owner = q; 1396 break; 1397 } 1398 } 1399 return the_owner; 1400 } 1401 } 1402 1403 class PrintOnClosure : public ThreadClosure { 1404 private: 1405 outputStream* _st; 1406 1407 public: 1408 PrintOnClosure(outputStream* st) : 1409 _st(st) {} 1410 1411 virtual void do_thread(Thread* thread) { 1412 if (thread != nullptr) { 1413 thread->print_on(_st); 1414 _st->cr(); 1415 } 1416 } 1417 }; 1418 1419 // Threads::print_on() is called at safepoint by VM_PrintThreads operation. 1420 void Threads::print_on(outputStream* st, bool print_stacks, 1421 bool internal_format, bool print_concurrent_locks, 1422 bool print_extended_info) { 1423 char buf[32]; 1424 st->print_raw_cr(os::local_time_string(buf, sizeof(buf))); 1425 1426 st->print_cr("Full thread dump %s (%s %s):", 1427 VM_Version::vm_name(), 1428 VM_Version::vm_release(), 1429 VM_Version::vm_info_string()); 1430 st->cr(); 1431 1432 #if INCLUDE_SERVICES 1433 // Dump concurrent locks 1434 ConcurrentLocksDump concurrent_locks; 1435 if (print_concurrent_locks) { 1436 concurrent_locks.dump_at_safepoint(); 1437 } 1438 #endif // INCLUDE_SERVICES 1439 1440 ThreadsSMRSupport::print_info_on(st); 1441 st->cr(); 1442 1443 ALL_JAVA_THREADS(p) { 1444 ResourceMark rm; 1445 p->print_on(st, print_extended_info); 1446 if (print_stacks) { 1447 if (internal_format) { 1448 p->trace_stack(); 1449 } else { 1450 p->print_stack_on(st); 1451 if (p->is_vthread_mounted()) { 1452 st->print_cr(" Mounted virtual thread #" INT64_FORMAT, java_lang_Thread::thread_id(p->vthread())); 1453 p->print_vthread_stack_on(st); 1454 } 1455 } 1456 } 1457 st->cr(); 1458 #if INCLUDE_SERVICES 1459 if (print_concurrent_locks) { 1460 concurrent_locks.print_locks_on(p, st); 1461 } 1462 #endif // INCLUDE_SERVICES 1463 } 1464 1465 PrintOnClosure cl(st); 1466 non_java_threads_do(&cl); 1467 1468 st->flush(); 1469 } 1470 1471 void Threads::print_on_error(Thread* this_thread, outputStream* st, Thread* current, char* buf, 1472 int buflen, bool* found_current) { 1473 if (this_thread != nullptr) { 1474 bool is_current = (current == this_thread); 1475 *found_current = *found_current || is_current; 1476 st->print("%s", is_current ? "=>" : " "); 1477 1478 st->print(PTR_FORMAT, p2i(this_thread)); 1479 st->print(" "); 1480 this_thread->print_on_error(st, buf, buflen); 1481 st->cr(); 1482 } 1483 } 1484 1485 class PrintOnErrorClosure : public ThreadClosure { 1486 outputStream* _st; 1487 Thread* _current; 1488 char* _buf; 1489 int _buflen; 1490 bool* _found_current; 1491 unsigned _num_printed; 1492 public: 1493 PrintOnErrorClosure(outputStream* st, Thread* current, char* buf, 1494 int buflen, bool* found_current) : 1495 _st(st), _current(current), _buf(buf), _buflen(buflen), _found_current(found_current), 1496 _num_printed(0) {} 1497 1498 virtual void do_thread(Thread* thread) { 1499 _num_printed++; 1500 Threads::print_on_error(thread, _st, _current, _buf, _buflen, _found_current); 1501 } 1502 1503 unsigned num_printed() const { return _num_printed; } 1504 }; 1505 1506 // Threads::print_on_error() is called by fatal error handler. It's possible 1507 // that VM is not at safepoint and/or current thread is inside signal handler. 1508 // Don't print stack trace, as the stack may not be walkable. Don't allocate 1509 // memory (even in resource area), it might deadlock the error handler. 1510 void Threads::print_on_error(outputStream* st, Thread* current, char* buf, 1511 int buflen) { 1512 ThreadsSMRSupport::print_info_on(st); 1513 st->cr(); 1514 1515 bool found_current = false; 1516 st->print_cr("Java Threads: ( => current thread )"); 1517 unsigned num_java = 0; 1518 ALL_JAVA_THREADS(thread) { 1519 print_on_error(thread, st, current, buf, buflen, &found_current); 1520 num_java++; 1521 } 1522 st->print_cr("Total: %u", num_java); 1523 st->cr(); 1524 1525 st->print_cr("Other Threads:"); 1526 unsigned num_other = ((VMThread::vm_thread() != nullptr) ? 1 : 0) + 1527 ((WatcherThread::watcher_thread() != nullptr) ? 1 : 0) + 1528 ((AsyncLogWriter::instance() != nullptr) ? 1 : 0); 1529 print_on_error(VMThread::vm_thread(), st, current, buf, buflen, &found_current); 1530 print_on_error(WatcherThread::watcher_thread(), st, current, buf, buflen, &found_current); 1531 print_on_error(AsyncLogWriter::instance(), st, current, buf, buflen, &found_current); 1532 1533 if (Universe::heap() != nullptr) { 1534 PrintOnErrorClosure print_closure(st, current, buf, buflen, &found_current); 1535 Universe::heap()->gc_threads_do(&print_closure); 1536 num_other += print_closure.num_printed(); 1537 } 1538 1539 if (!found_current) { 1540 st->cr(); 1541 st->print("=>" PTR_FORMAT " (exited) ", p2i(current)); 1542 current->print_on_error(st, buf, buflen); 1543 num_other++; 1544 st->cr(); 1545 } 1546 st->print_cr("Total: %u", num_other); 1547 st->cr(); 1548 1549 st->print_cr("Threads with active compile tasks:"); 1550 unsigned num = print_threads_compiling(st, buf, buflen); 1551 st->print_cr("Total: %u", num); 1552 } 1553 1554 unsigned Threads::print_threads_compiling(outputStream* st, char* buf, int buflen, bool short_form) { 1555 unsigned num = 0; 1556 ALL_JAVA_THREADS(thread) { 1557 if (thread->is_Compiler_thread()) { 1558 CompilerThread* ct = (CompilerThread*) thread; 1559 1560 // Keep task in local variable for null check. 1561 // ct->_task might be set to null by concurring compiler thread 1562 // because it completed the compilation. The task is never freed, 1563 // though, just returned to a free list. 1564 CompileTask* task = ct->task(); 1565 if (task != nullptr) { 1566 thread->print_name_on_error(st, buf, buflen); 1567 st->print(" "); 1568 task->print(st, nullptr, short_form, true); 1569 num++; 1570 } 1571 } 1572 } 1573 return num; 1574 } 1575 1576 void Threads::verify() { 1577 ALL_JAVA_THREADS(p) { 1578 p->verify(); 1579 } 1580 VMThread* thread = VMThread::vm_thread(); 1581 if (thread != nullptr) thread->verify(); 1582 }