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