1 /* 2 * Copyright (c) 1997, 2023, 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/metaspaceShared.hpp" 29 #include "classfile/classLoader.hpp" 30 #include "classfile/javaClasses.hpp" 31 #include "classfile/javaThreadStatus.hpp" 32 #include "classfile/systemDictionary.hpp" 33 #include "classfile/vmClasses.hpp" 34 #include "classfile/vmSymbols.hpp" 35 #include "compiler/compileBroker.hpp" 36 #include "compiler/compileTask.hpp" 37 #include "compiler/compilerThread.hpp" 38 #include "gc/shared/barrierSet.hpp" 39 #include "gc/shared/barrierSetNMethod.hpp" 40 #include "gc/shared/gcVMOperations.hpp" 41 #include "gc/shared/oopStorage.hpp" 42 #include "gc/shared/oopStorageSet.hpp" 43 #include "gc/shared/stringdedup/stringDedup.hpp" 44 #include "jfr/jfrEvents.hpp" 45 #include "jvm.h" 46 #include "jvmtifiles/jvmtiEnv.hpp" 47 #include "logging/log.hpp" 48 #include "logging/logAsyncWriter.hpp" 49 #include "logging/logConfiguration.hpp" 50 #include "memory/allocation.inline.hpp" 51 #include "memory/iterator.hpp" 52 #include "memory/oopFactory.hpp" 53 #include "memory/resourceArea.hpp" 54 #include "memory/universe.hpp" 55 #include "oops/instanceKlass.hpp" 56 #include "oops/klass.inline.hpp" 57 #include "oops/oop.inline.hpp" 58 #include "oops/symbol.hpp" 59 #include "prims/jvmtiAgentList.hpp" 60 #include "prims/jvm_misc.hpp" 61 #include "runtime/arguments.hpp" 62 #include "runtime/fieldDescriptor.inline.hpp" 63 #include "runtime/flags/jvmFlagLimit.hpp" 64 #include "runtime/handles.inline.hpp" 65 #include "runtime/globals.hpp" 66 #include "runtime/interfaceSupport.inline.hpp" 67 #include "runtime/java.hpp" 68 #include "runtime/javaCalls.hpp" 69 #include "runtime/javaThread.inline.hpp" 70 #include "runtime/jniHandles.inline.hpp" 71 #include "runtime/jniPeriodicChecker.hpp" 72 #include "runtime/lockStack.inline.hpp" 73 #include "runtime/monitorDeflationThread.hpp" 74 #include "runtime/mutexLocker.hpp" 75 #include "runtime/nonJavaThread.hpp" 76 #include "runtime/objectMonitor.inline.hpp" 77 #include "runtime/osThread.hpp" 78 #include "runtime/safepoint.hpp" 79 #include "runtime/safepointMechanism.inline.hpp" 80 #include "runtime/safepointVerifiers.hpp" 81 #include "runtime/serviceThread.hpp" 82 #include "runtime/sharedRuntime.hpp" 83 #include "runtime/statSampler.hpp" 84 #include "runtime/stubCodeGenerator.hpp" 85 #include "runtime/thread.inline.hpp" 86 #include "runtime/threads.hpp" 87 #include "runtime/threadSMR.inline.hpp" 88 #include "runtime/timer.hpp" 89 #include "runtime/timerTrace.hpp" 90 #include "runtime/trimNativeHeap.hpp" 91 #include "runtime/vmOperations.hpp" 92 #include "runtime/vm_version.hpp" 93 #include "services/attachListener.hpp" 94 #include "services/management.hpp" 95 #include "services/memTracker.hpp" 96 #include "services/threadIdTable.hpp" 97 #include "services/threadService.hpp" 98 #include "utilities/dtrace.hpp" 99 #include "utilities/events.hpp" 100 #include "utilities/macros.hpp" 101 #include "utilities/vmError.hpp" 102 #if INCLUDE_JVMCI 103 #include "jvmci/jvmci.hpp" 104 #include "jvmci/jvmciEnv.hpp" 105 #endif 106 #ifdef COMPILER2 107 #include "opto/idealGraphPrinter.hpp" 108 #endif 109 #if INCLUDE_RTM_OPT 110 #include "runtime/rtmLocking.hpp" 111 #endif 112 #if INCLUDE_JFR 113 #include "jfr/jfr.hpp" 114 #endif 115 116 // Initialization after module runtime initialization 117 void universe_post_module_init(); // must happen after call_initPhase2 118 119 120 static void initialize_class(Symbol* class_name, TRAPS) { 121 Klass* klass = SystemDictionary::resolve_or_fail(class_name, true, CHECK); 122 InstanceKlass::cast(klass)->initialize(CHECK); 123 } 124 125 126 // Creates the initial ThreadGroup 127 static Handle create_initial_thread_group(TRAPS) { 128 Handle system_instance = JavaCalls::construct_new_instance( 129 vmClasses::ThreadGroup_klass(), 130 vmSymbols::void_method_signature(), 131 CHECK_NH); 132 Universe::set_system_thread_group(system_instance()); 133 134 Handle string = java_lang_String::create_from_str("main", CHECK_NH); 135 Handle main_instance = JavaCalls::construct_new_instance( 136 vmClasses::ThreadGroup_klass(), 137 vmSymbols::threadgroup_string_void_signature(), 138 system_instance, 139 string, 140 CHECK_NH); 141 return main_instance; 142 } 143 144 // Creates the initial Thread, and sets it to running. 145 static void create_initial_thread(Handle thread_group, JavaThread* thread, 146 TRAPS) { 147 InstanceKlass* ik = vmClasses::Thread_klass(); 148 assert(ik->is_initialized(), "must be"); 149 instanceHandle thread_oop = ik->allocate_instance_handle(CHECK); 150 151 // Cannot use JavaCalls::construct_new_instance because the java.lang.Thread 152 // constructor calls Thread.current(), which must be set here for the 153 // initial thread. 154 java_lang_Thread::set_thread(thread_oop(), thread); 155 thread->set_threadOopHandles(thread_oop()); 156 157 Handle string = java_lang_String::create_from_str("main", CHECK); 158 159 JavaValue result(T_VOID); 160 JavaCalls::call_special(&result, thread_oop, 161 ik, 162 vmSymbols::object_initializer_name(), 163 vmSymbols::threadgroup_string_void_signature(), 164 thread_group, 165 string, 166 CHECK); 167 168 // Set thread status to running since main thread has 169 // been started and running. 170 java_lang_Thread::set_thread_status(thread_oop(), 171 JavaThreadStatus::RUNNABLE); 172 } 173 174 // Extract version and vendor specific information from 175 // java.lang.VersionProps fields. 176 // Returned char* is allocated in the thread's resource area 177 // so must be copied for permanency. 178 static const char* get_java_version_info(InstanceKlass* ik, 179 Symbol* field_name) { 180 fieldDescriptor fd; 181 bool found = ik != nullptr && 182 ik->find_local_field(field_name, 183 vmSymbols::string_signature(), &fd); 184 if (found) { 185 oop name_oop = ik->java_mirror()->obj_field(fd.offset()); 186 if (name_oop == nullptr) { 187 return nullptr; 188 } 189 const char* name = java_lang_String::as_utf8_string(name_oop); 190 return name; 191 } else { 192 return nullptr; 193 } 194 } 195 196 // ======= Threads ======== 197 198 // The Threads class links together all active threads, and provides 199 // operations over all threads. It is protected by the Threads_lock, 200 // which is also used in other global contexts like safepointing. 201 // ThreadsListHandles are used to safely perform operations on one 202 // or more threads without the risk of the thread exiting during the 203 // operation. 204 // 205 // Note: The Threads_lock is currently more widely used than we 206 // would like. We are actively migrating Threads_lock uses to other 207 // mechanisms in order to reduce Threads_lock contention. 208 209 int Threads::_number_of_threads = 0; 210 int Threads::_number_of_non_daemon_threads = 0; 211 int Threads::_return_code = 0; 212 uintx Threads::_thread_claim_token = 1; // Never zero. 213 214 #ifdef ASSERT 215 bool Threads::_vm_complete = false; 216 #endif 217 218 // General purpose hook into Java code, run once when the VM is initialized. 219 // The Java library method itself may be changed independently from the VM. 220 static void call_postVMInitHook(TRAPS) { 221 Klass* klass = SystemDictionary::resolve_or_null(vmSymbols::jdk_internal_vm_PostVMInitHook(), THREAD); 222 if (klass != nullptr) { 223 JavaValue result(T_VOID); 224 JavaCalls::call_static(&result, klass, vmSymbols::run_method_name(), 225 vmSymbols::void_method_signature(), 226 CHECK); 227 } 228 } 229 230 // All NonJavaThreads (i.e., every non-JavaThread in the system). 231 void Threads::non_java_threads_do(ThreadClosure* tc) { 232 NoSafepointVerifier nsv; 233 for (NonJavaThread::Iterator njti; !njti.end(); njti.step()) { 234 tc->do_thread(njti.current()); 235 } 236 } 237 238 // All JavaThreads 239 #define ALL_JAVA_THREADS(X) \ 240 for (JavaThread* X : *ThreadsSMRSupport::get_java_thread_list()) 241 242 // All JavaThreads 243 void Threads::java_threads_do(ThreadClosure* tc) { 244 assert_locked_or_safepoint(Threads_lock); 245 // ALL_JAVA_THREADS iterates through all JavaThreads. 246 ALL_JAVA_THREADS(p) { 247 tc->do_thread(p); 248 } 249 } 250 251 // All JavaThreads + all non-JavaThreads (i.e., every thread in the system). 252 void Threads::threads_do(ThreadClosure* tc) { 253 assert_locked_or_safepoint(Threads_lock); 254 java_threads_do(tc); 255 non_java_threads_do(tc); 256 } 257 258 void Threads::possibly_parallel_threads_do(bool is_par, ThreadClosure* tc) { 259 assert_at_safepoint(); 260 261 uintx claim_token = Threads::thread_claim_token(); 262 ALL_JAVA_THREADS(p) { 263 if (p->claim_threads_do(is_par, claim_token)) { 264 tc->do_thread(p); 265 } 266 } 267 for (NonJavaThread::Iterator njti; !njti.end(); njti.step()) { 268 Thread* current = njti.current(); 269 if (current->claim_threads_do(is_par, claim_token)) { 270 tc->do_thread(current); 271 } 272 } 273 } 274 275 // The system initialization in the library has three phases. 276 // 277 // Phase 1: java.lang.System class initialization 278 // java.lang.System is a primordial class loaded and initialized 279 // by the VM early during startup. java.lang.System.<clinit> 280 // only does registerNatives and keeps the rest of the class 281 // initialization work later until thread initialization completes. 282 // 283 // System.initPhase1 initializes the system properties, the static 284 // fields in, out, and err. Set up java signal handlers, OS-specific 285 // system settings, and thread group of the main thread. 286 static void call_initPhase1(TRAPS) { 287 Klass* klass = vmClasses::System_klass(); 288 JavaValue result(T_VOID); 289 JavaCalls::call_static(&result, klass, vmSymbols::initPhase1_name(), 290 vmSymbols::void_method_signature(), CHECK); 291 } 292 293 // Phase 2. Module system initialization 294 // This will initialize the module system. Only java.base classes 295 // can be loaded until phase 2 completes. 296 // 297 // Call System.initPhase2 after the compiler initialization and jsr292 298 // classes get initialized because module initialization runs a lot of java 299 // code, that for performance reasons, should be compiled. Also, this will 300 // enable the startup code to use lambda and other language features in this 301 // phase and onward. 302 // 303 // After phase 2, The VM will begin search classes from -Xbootclasspath/a. 304 static void call_initPhase2(TRAPS) { 305 TraceTime timer("Initialize module system", TRACETIME_LOG(Info, startuptime)); 306 307 Klass* klass = vmClasses::System_klass(); 308 309 JavaValue result(T_INT); 310 JavaCallArguments args; 311 args.push_int(DisplayVMOutputToStderr); 312 args.push_int(log_is_enabled(Debug, init)); // print stack trace if exception thrown 313 JavaCalls::call_static(&result, klass, vmSymbols::initPhase2_name(), 314 vmSymbols::boolean_boolean_int_signature(), &args, CHECK); 315 if (result.get_jint() != JNI_OK) { 316 vm_exit_during_initialization(); // no message or exception 317 } 318 319 universe_post_module_init(); 320 } 321 322 // Phase 3. final setup - set security manager, system class loader and TCCL 323 // 324 // This will instantiate and set the security manager, set the system class 325 // loader as well as the thread context class loader. The security manager 326 // and system class loader may be a custom class loaded from -Xbootclasspath/a, 327 // other modules or the application's classpath. 328 static void call_initPhase3(TRAPS) { 329 Klass* klass = vmClasses::System_klass(); 330 JavaValue result(T_VOID); 331 JavaCalls::call_static(&result, klass, vmSymbols::initPhase3_name(), 332 vmSymbols::void_method_signature(), CHECK); 333 } 334 335 void Threads::initialize_java_lang_classes(JavaThread* main_thread, TRAPS) { 336 TraceTime timer("Initialize java.lang classes", TRACETIME_LOG(Info, startuptime)); 337 338 initialize_class(vmSymbols::java_lang_String(), CHECK); 339 340 // Inject CompactStrings value after the static initializers for String ran. 341 java_lang_String::set_compact_strings(CompactStrings); 342 343 // Initialize java_lang.System (needed before creating the thread) 344 initialize_class(vmSymbols::java_lang_System(), CHECK); 345 // The VM creates & returns objects of this class. Make sure it's initialized. 346 initialize_class(vmSymbols::java_lang_Class(), CHECK); 347 initialize_class(vmSymbols::java_lang_ThreadGroup(), CHECK); 348 Handle thread_group = create_initial_thread_group(CHECK); 349 Universe::set_main_thread_group(thread_group()); 350 initialize_class(vmSymbols::java_lang_Thread(), CHECK); 351 create_initial_thread(thread_group, main_thread, CHECK); 352 353 // The VM creates objects of this class. 354 initialize_class(vmSymbols::java_lang_Module(), CHECK); 355 356 #ifdef ASSERT 357 InstanceKlass *k = vmClasses::UnsafeConstants_klass(); 358 assert(k->is_not_initialized(), "UnsafeConstants should not already be initialized"); 359 #endif 360 361 // initialize the hardware-specific constants needed by Unsafe 362 initialize_class(vmSymbols::jdk_internal_misc_UnsafeConstants(), CHECK); 363 jdk_internal_misc_UnsafeConstants::set_unsafe_constants(); 364 365 // The VM preresolves methods to these classes. Make sure that they get initialized 366 initialize_class(vmSymbols::java_lang_reflect_Method(), CHECK); 367 initialize_class(vmSymbols::java_lang_ref_Finalizer(), CHECK); 368 369 // Phase 1 of the system initialization in the library, java.lang.System class initialization 370 call_initPhase1(CHECK); 371 372 // Get the Java runtime name, version, and vendor info after java.lang.System is initialized. 373 // Some values are actually configure-time constants but some can be set via the jlink tool and 374 // so must be read dynamically. We treat them all the same. 375 InstanceKlass* ik = SystemDictionary::find_instance_klass(THREAD, vmSymbols::java_lang_VersionProps(), 376 Handle(), Handle()); 377 { 378 ResourceMark rm(main_thread); 379 JDK_Version::set_java_version(get_java_version_info(ik, vmSymbols::java_version_name())); 380 381 JDK_Version::set_runtime_name(get_java_version_info(ik, vmSymbols::java_runtime_name_name())); 382 383 JDK_Version::set_runtime_version(get_java_version_info(ik, vmSymbols::java_runtime_version_name())); 384 385 JDK_Version::set_runtime_vendor_version(get_java_version_info(ik, vmSymbols::java_runtime_vendor_version_name())); 386 387 JDK_Version::set_runtime_vendor_vm_bug_url(get_java_version_info(ik, vmSymbols::java_runtime_vendor_vm_bug_url_name())); 388 } 389 390 // an instance of OutOfMemory exception has been allocated earlier 391 initialize_class(vmSymbols::java_lang_OutOfMemoryError(), CHECK); 392 initialize_class(vmSymbols::java_lang_NullPointerException(), CHECK); 393 initialize_class(vmSymbols::java_lang_ClassCastException(), CHECK); 394 initialize_class(vmSymbols::java_lang_ArrayStoreException(), CHECK); 395 initialize_class(vmSymbols::java_lang_ArithmeticException(), CHECK); 396 initialize_class(vmSymbols::java_lang_StackOverflowError(), CHECK); 397 initialize_class(vmSymbols::java_lang_IllegalMonitorStateException(), CHECK); 398 initialize_class(vmSymbols::java_lang_IllegalArgumentException(), CHECK); 399 } 400 401 void Threads::initialize_jsr292_core_classes(TRAPS) { 402 TraceTime timer("Initialize java.lang.invoke classes", TRACETIME_LOG(Info, startuptime)); 403 404 initialize_class(vmSymbols::java_lang_invoke_MethodHandle(), CHECK); 405 initialize_class(vmSymbols::java_lang_invoke_ResolvedMethodName(), CHECK); 406 initialize_class(vmSymbols::java_lang_invoke_MemberName(), CHECK); 407 initialize_class(vmSymbols::java_lang_invoke_MethodHandleNatives(), CHECK); 408 } 409 410 jint Threads::create_vm(JavaVMInitArgs* args, bool* canTryAgain) { 411 extern void JDK_Version_init(); 412 413 // Preinitialize version info. 414 VM_Version::early_initialize(); 415 416 // Check version 417 if (!is_supported_jni_version(args->version)) return JNI_EVERSION; 418 419 // Initialize library-based TLS 420 ThreadLocalStorage::init(); 421 422 // Initialize the output stream module 423 ostream_init(); 424 425 // Process java launcher properties. 426 Arguments::process_sun_java_launcher_properties(args); 427 428 // Initialize the os module 429 os::init(); 430 431 MACOS_AARCH64_ONLY(os::current_thread_enable_wx(WXWrite)); 432 433 // Record VM creation timing statistics 434 TraceVmCreationTime create_vm_timer; 435 create_vm_timer.start(); 436 437 // Initialize system properties. 438 Arguments::init_system_properties(); 439 440 // So that JDK version can be used as a discriminator when parsing arguments 441 JDK_Version_init(); 442 443 // Update/Initialize System properties after JDK version number is known 444 Arguments::init_version_specific_system_properties(); 445 446 // Make sure to initialize log configuration *before* parsing arguments 447 LogConfiguration::initialize(create_vm_timer.begin_time()); 448 449 // Parse arguments 450 // Note: this internally calls os::init_container_support() 451 jint parse_result = Arguments::parse(args); 452 if (parse_result != JNI_OK) return parse_result; 453 454 // Initialize NMT right after argument parsing to keep the pre-NMT-init window small. 455 MemTracker::initialize(); 456 457 os::init_before_ergo(); 458 459 jint ergo_result = Arguments::apply_ergo(); 460 if (ergo_result != JNI_OK) return ergo_result; 461 462 // Final check of all ranges after ergonomics which may change values. 463 if (!JVMFlagLimit::check_all_ranges()) { 464 return JNI_EINVAL; 465 } 466 467 // Final check of all 'AfterErgo' constraints after ergonomics which may change values. 468 bool constraint_result = JVMFlagLimit::check_all_constraints(JVMFlagConstraintPhase::AfterErgo); 469 if (!constraint_result) { 470 return JNI_EINVAL; 471 } 472 473 if (PauseAtStartup) { 474 os::pause(); 475 } 476 477 HOTSPOT_VM_INIT_BEGIN(); 478 479 // Timing (must come after argument parsing) 480 TraceTime timer("Create VM", TRACETIME_LOG(Info, startuptime)); 481 482 // Initialize the os module after parsing the args 483 jint os_init_2_result = os::init_2(); 484 if (os_init_2_result != JNI_OK) return os_init_2_result; 485 486 #ifdef CAN_SHOW_REGISTERS_ON_ASSERT 487 // Initialize assert poison page mechanism. 488 if (ShowRegistersOnAssert) { 489 initialize_assert_poison(); 490 } 491 #endif // CAN_SHOW_REGISTERS_ON_ASSERT 492 493 SafepointMechanism::initialize(); 494 495 jint adjust_after_os_result = Arguments::adjust_after_os(); 496 if (adjust_after_os_result != JNI_OK) return adjust_after_os_result; 497 498 // Initialize output stream logging 499 ostream_init_log(); 500 501 // Launch -agentlib/-agentpath and converted -Xrun agents 502 JvmtiAgentList::load_agents(); 503 504 // Initialize Threads state 505 _number_of_threads = 0; 506 _number_of_non_daemon_threads = 0; 507 508 // Initialize global data structures and create system classes in heap 509 vm_init_globals(); 510 511 #if INCLUDE_JVMCI 512 if (JVMCICounterSize > 0) { 513 JavaThread::_jvmci_old_thread_counters = NEW_C_HEAP_ARRAY(jlong, JVMCICounterSize, mtJVMCI); 514 memset(JavaThread::_jvmci_old_thread_counters, 0, sizeof(jlong) * JVMCICounterSize); 515 } else { 516 JavaThread::_jvmci_old_thread_counters = nullptr; 517 } 518 #endif // INCLUDE_JVMCI 519 520 // Initialize OopStorage for threadObj 521 JavaThread::_thread_oop_storage = OopStorageSet::create_strong("Thread OopStorage", mtThread); 522 523 // Attach the main thread to this os thread 524 JavaThread* main_thread = new JavaThread(); 525 main_thread->set_thread_state(_thread_in_vm); 526 main_thread->initialize_thread_current(); 527 // must do this before set_active_handles 528 main_thread->record_stack_base_and_size(); 529 main_thread->register_thread_stack_with_NMT(); 530 main_thread->set_active_handles(JNIHandleBlock::allocate_block()); 531 MACOS_AARCH64_ONLY(main_thread->init_wx()); 532 533 if (!main_thread->set_as_starting_thread()) { 534 vm_shutdown_during_initialization( 535 "Failed necessary internal allocation. Out of swap space"); 536 main_thread->smr_delete(); 537 *canTryAgain = false; // don't let caller call JNI_CreateJavaVM again 538 return JNI_ENOMEM; 539 } 540 541 // Enable guard page *after* os::create_main_thread(), otherwise it would 542 // crash Linux VM, see notes in os_linux.cpp. 543 main_thread->stack_overflow_state()->create_stack_guard_pages(); 544 545 // Initialize Java-Level synchronization subsystem 546 ObjectMonitor::Initialize(); 547 ObjectSynchronizer::initialize(); 548 549 // Initialize global modules 550 jint status = init_globals(); 551 if (status != JNI_OK) { 552 main_thread->smr_delete(); 553 *canTryAgain = false; // don't let caller call JNI_CreateJavaVM again 554 return status; 555 } 556 557 // Create WatcherThread as soon as we can since we need it in case 558 // of hangs during error reporting. 559 WatcherThread::start(); 560 561 // Add main_thread to threads list to finish barrier setup with 562 // on_thread_attach. Should be before starting to build Java objects in 563 // init_globals2, which invokes barriers. 564 { 565 MutexLocker mu(Threads_lock); 566 Threads::add(main_thread); 567 } 568 569 status = init_globals2(); 570 if (status != JNI_OK) { 571 Threads::remove(main_thread, false); 572 // It is possible that we managed to fully initialize Universe but have then 573 // failed by throwing an exception. In that case our caller JNI_CreateJavaVM 574 // will want to report it, so we can't delete the main thread. 575 if (!main_thread->has_pending_exception()) { 576 main_thread->smr_delete(); 577 } 578 *canTryAgain = false; // don't let caller call JNI_CreateJavaVM again 579 return status; 580 } 581 582 JFR_ONLY(Jfr::on_create_vm_1();) 583 584 // Should be done after the heap is fully created 585 main_thread->cache_global_variables(); 586 587 // Any JVMTI raw monitors entered in onload will transition into 588 // real raw monitor. VM is setup enough here for raw monitor enter. 589 JvmtiExport::transition_pending_onload_raw_monitors(); 590 591 // Create the VMThread 592 { TraceTime timer("Start VMThread", TRACETIME_LOG(Info, startuptime)); 593 594 VMThread::create(); 595 VMThread* vmthread = VMThread::vm_thread(); 596 597 if (!os::create_thread(vmthread, os::vm_thread)) { 598 vm_exit_during_initialization("Cannot create VM thread. " 599 "Out of system resources."); 600 } 601 602 // Wait for the VM thread to become ready, and VMThread::run to initialize 603 // Monitors can have spurious returns, must always check another state flag 604 { 605 MonitorLocker ml(Notify_lock); 606 os::start_thread(vmthread); 607 while (!vmthread->is_running()) { 608 ml.wait(); 609 } 610 } 611 } 612 613 assert(Universe::is_fully_initialized(), "not initialized"); 614 if (VerifyDuringStartup) { 615 // Make sure we're starting with a clean slate. 616 VM_Verify verify_op; 617 VMThread::execute(&verify_op); 618 } 619 620 // We need this to update the java.vm.info property in case any flags used 621 // to initially define it have been changed. This is needed for both CDS 622 // since UseSharedSpaces may be changed after java.vm.info 623 // is initially computed. See Abstract_VM_Version::vm_info_string(). 624 // This update must happen before we initialize the java classes, but 625 // after any initialization logic that might modify the flags. 626 Arguments::update_vm_info_property(VM_Version::vm_info_string()); 627 628 JavaThread* THREAD = JavaThread::current(); // For exception macros. 629 HandleMark hm(THREAD); 630 631 // Always call even when there are not JVMTI environments yet, since environments 632 // may be attached late and JVMTI must track phases of VM execution 633 JvmtiExport::enter_early_start_phase(); 634 635 // Notify JVMTI agents that VM has started (JNI is up) - nop if no agents. 636 JvmtiExport::post_early_vm_start(); 637 638 // Launch -Xrun agents early if EagerXrunInit is set 639 if (EagerXrunInit) { 640 JvmtiAgentList::load_xrun_agents(); 641 } 642 643 initialize_java_lang_classes(main_thread, CHECK_JNI_ERR); 644 645 quicken_jni_functions(); 646 647 // No more stub generation allowed after that point. 648 StubCodeDesc::freeze(); 649 650 // Set flag that basic initialization has completed. Used by exceptions and various 651 // debug stuff, that does not work until all basic classes have been initialized. 652 set_init_completed(); 653 654 LogConfiguration::post_initialize(); 655 Metaspace::post_initialize(); 656 MutexLocker::post_initialize(); 657 658 HOTSPOT_VM_INIT_END(); 659 660 // record VM initialization completion time 661 #if INCLUDE_MANAGEMENT 662 Management::record_vm_init_completed(); 663 #endif // INCLUDE_MANAGEMENT 664 665 log_info(os)("Initialized VM with process ID %d", os::current_process_id()); 666 667 // Signal Dispatcher needs to be started before VMInit event is posted 668 os::initialize_jdk_signal_support(CHECK_JNI_ERR); 669 670 // Start Attach Listener if +StartAttachListener or it can't be started lazily 671 if (!DisableAttachMechanism) { 672 AttachListener::vm_start(); 673 if (StartAttachListener || AttachListener::init_at_startup()) { 674 AttachListener::init(); 675 } 676 } 677 678 // Launch -Xrun agents if EagerXrunInit is not set. 679 if (!EagerXrunInit) { 680 JvmtiAgentList::load_xrun_agents(); 681 } 682 683 Arena::start_chunk_pool_cleaner_task(); 684 685 // Start the service thread 686 // The service thread enqueues JVMTI deferred events and does various hashtable 687 // and other cleanups. Needs to start before the compilers start posting events. 688 ServiceThread::initialize(); 689 690 // Start the monitor deflation thread: 691 MonitorDeflationThread::initialize(); 692 693 // initialize compiler(s) 694 #if defined(COMPILER1) || COMPILER2_OR_JVMCI 695 #if INCLUDE_JVMCI 696 bool force_JVMCI_intialization = false; 697 if (EnableJVMCI) { 698 // Initialize JVMCI eagerly when it is explicitly requested. 699 // Or when JVMCILibDumpJNIConfig or JVMCIPrintProperties is enabled. 700 force_JVMCI_intialization = EagerJVMCI || JVMCIPrintProperties || JVMCILibDumpJNIConfig; 701 702 if (!force_JVMCI_intialization) { 703 // 8145270: Force initialization of JVMCI runtime otherwise requests for blocking 704 // compilations via JVMCI will not actually block until JVMCI is initialized. 705 force_JVMCI_intialization = UseJVMCICompiler && (!UseInterpreter || !BackgroundCompilation); 706 } 707 } 708 #endif 709 CompileBroker::compilation_init_phase1(CHECK_JNI_ERR); 710 // Postpone completion of compiler initialization to after JVMCI 711 // is initialized to avoid timeouts of blocking compilations. 712 if (JVMCI_ONLY(!force_JVMCI_intialization) NOT_JVMCI(true)) { 713 CompileBroker::compilation_init_phase2(); 714 } 715 #endif 716 717 // Start string deduplication thread if requested. 718 if (StringDedup::is_enabled()) { 719 StringDedup::start(); 720 } 721 722 // Pre-initialize some JSR292 core classes to avoid deadlock during class loading. 723 // It is done after compilers are initialized, because otherwise compilations of 724 // signature polymorphic MH intrinsics can be missed 725 // (see SystemDictionary::find_method_handle_intrinsic). 726 initialize_jsr292_core_classes(CHECK_JNI_ERR); 727 728 // This will initialize the module system. Only java.base classes can be 729 // loaded until phase 2 completes 730 call_initPhase2(CHECK_JNI_ERR); 731 732 JFR_ONLY(Jfr::on_create_vm_2();) 733 734 // Always call even when there are not JVMTI environments yet, since environments 735 // may be attached late and JVMTI must track phases of VM execution 736 JvmtiExport::enter_start_phase(); 737 738 // Notify JVMTI agents that VM has started (JNI is up) - nop if no agents. 739 JvmtiExport::post_vm_start(); 740 741 // Final system initialization including security manager and system class loader 742 call_initPhase3(CHECK_JNI_ERR); 743 744 // cache the system and platform class loaders 745 SystemDictionary::compute_java_loaders(CHECK_JNI_ERR); 746 747 #if INCLUDE_CDS 748 // capture the module path info from the ModuleEntryTable 749 ClassLoader::initialize_module_path(THREAD); 750 if (HAS_PENDING_EXCEPTION) { 751 java_lang_Throwable::print(PENDING_EXCEPTION, tty); 752 vm_exit_during_initialization("ClassLoader::initialize_module_path() failed unexpectedly"); 753 } 754 #endif 755 756 #if INCLUDE_JVMCI 757 if (force_JVMCI_intialization) { 758 JVMCI::initialize_compiler(CHECK_JNI_ERR); 759 CompileBroker::compilation_init_phase2(); 760 } 761 #endif 762 763 if (NativeHeapTrimmer::enabled()) { 764 NativeHeapTrimmer::initialize(); 765 } 766 767 // Always call even when there are not JVMTI environments yet, since environments 768 // may be attached late and JVMTI must track phases of VM execution 769 JvmtiExport::enter_live_phase(); 770 771 // Make perfmemory accessible 772 PerfMemory::set_accessible(true); 773 774 // Notify JVMTI agents that VM initialization is complete - nop if no agents. 775 JvmtiExport::post_vm_initialized(); 776 777 JFR_ONLY(Jfr::on_create_vm_3();) 778 779 #if INCLUDE_MANAGEMENT 780 Management::initialize(THREAD); 781 782 if (HAS_PENDING_EXCEPTION) { 783 // management agent fails to start possibly due to 784 // configuration problem and is responsible for printing 785 // stack trace if appropriate. Simply exit VM. 786 vm_exit(1); 787 } 788 #endif // INCLUDE_MANAGEMENT 789 790 StatSampler::engage(); 791 if (CheckJNICalls) JniPeriodicChecker::engage(); 792 793 #if INCLUDE_RTM_OPT 794 RTMLockingCounters::init(); 795 #endif 796 797 call_postVMInitHook(THREAD); 798 // The Java side of PostVMInitHook.run must deal with all 799 // exceptions and provide means of diagnosis. 800 if (HAS_PENDING_EXCEPTION) { 801 CLEAR_PENDING_EXCEPTION; 802 } 803 804 // Let WatcherThread run all registered periodic tasks now. 805 // NOTE: All PeriodicTasks should be registered by now. If they 806 // aren't, late joiners might appear to start slowly (we might 807 // take a while to process their first tick). 808 WatcherThread::run_all_tasks(); 809 810 create_vm_timer.end(); 811 #ifdef ASSERT 812 _vm_complete = true; 813 #endif 814 815 if (DumpSharedSpaces) { 816 MetaspaceShared::preload_and_dump(); 817 } 818 819 return JNI_OK; 820 } 821 822 // Threads::destroy_vm() is normally called from jni_DestroyJavaVM() when 823 // the program falls off the end of main(). Another VM exit path is through 824 // vm_exit() when the program calls System.exit() to return a value or when 825 // there is a serious error in VM. The two shutdown paths are not exactly 826 // the same, but they share Shutdown.shutdown() at Java level and before_exit() 827 // and VM_Exit op at VM level. 828 // 829 // Shutdown sequence: 830 // + Shutdown native memory tracking if it is on 831 // + Wait until we are the last non-daemon thread to execute 832 // <-- every thing is still working at this moment --> 833 // + Call java.lang.Shutdown.shutdown(), which will invoke Java level 834 // shutdown hooks 835 // + Call before_exit(), prepare for VM exit 836 // > run VM level shutdown hooks (they are registered through JVM_OnExit(), 837 // currently the only user of this mechanism is File.deleteOnExit()) 838 // > stop StatSampler, watcher thread, 839 // post thread end and vm death events to JVMTI, 840 // stop signal thread 841 // + Call JavaThread::exit(), it will: 842 // > release JNI handle blocks, remove stack guard pages 843 // > remove this thread from Threads list 844 // <-- no more Java code from this thread after this point --> 845 // + Stop VM thread, it will bring the remaining VM to a safepoint and stop 846 // the compiler threads at safepoint 847 // <-- do not use anything that could get blocked by Safepoint --> 848 // + Disable tracing at JNI/JVM barriers 849 // + Set _vm_exited flag for threads that are still running native code 850 // + Call exit_globals() 851 // > deletes tty 852 // > deletes PerfMemory resources 853 // + Delete this thread 854 // + Return to caller 855 856 void Threads::destroy_vm() { 857 JavaThread* thread = JavaThread::current(); 858 859 #ifdef ASSERT 860 _vm_complete = false; 861 #endif 862 // Wait until we are the last non-daemon thread to execute, or 863 // if we are a daemon then wait until the last non-daemon thread has 864 // executed. 865 bool daemon = java_lang_Thread::is_daemon(thread->threadObj()); 866 int expected = daemon ? 0 : 1; 867 { 868 MonitorLocker nu(Threads_lock); 869 while (Threads::number_of_non_daemon_threads() > expected) 870 // This wait should make safepoint checks, wait without a timeout. 871 nu.wait(0); 872 } 873 874 EventShutdown e; 875 if (e.should_commit()) { 876 e.set_reason("No remaining non-daemon Java threads"); 877 e.commit(); 878 } 879 880 // Hang forever on exit if we are reporting an error. 881 if (ShowMessageBoxOnError && VMError::is_error_reported()) { 882 os::infinite_sleep(); 883 } 884 os::wait_for_keypress_at_exit(); 885 886 // run Java level shutdown hooks 887 thread->invoke_shutdown_hooks(); 888 889 before_exit(thread); 890 891 thread->exit(true); 892 893 // We are no longer on the main thread list but could still be in a 894 // secondary list where another thread may try to interact with us. 895 // So wait until all such interactions are complete before we bring 896 // the VM to the termination safepoint. Normally this would be done 897 // using thread->smr_delete() below where we delete the thread, but 898 // we can't call that after the termination safepoint is active as 899 // we will deadlock on the Threads_lock. Once all interactions are 900 // complete it is safe to directly delete the thread at any time. 901 ThreadsSMRSupport::wait_until_not_protected(thread); 902 903 // Stop VM thread. 904 { 905 // 4945125 The vm thread comes to a safepoint during exit. 906 // GC vm_operations can get caught at the safepoint, and the 907 // heap is unparseable if they are caught. Grab the Heap_lock 908 // to prevent this. The GC vm_operations will not be able to 909 // queue until after the vm thread is dead. After this point, 910 // we'll never emerge out of the safepoint before the VM exits. 911 // Assert that the thread is terminated so that acquiring the 912 // Heap_lock doesn't cause the terminated thread to participate in 913 // the safepoint protocol. 914 915 assert(thread->is_terminated(), "must be terminated here"); 916 MutexLocker ml(Heap_lock); 917 918 VMThread::wait_for_vm_thread_exit(); 919 assert(SafepointSynchronize::is_at_safepoint(), "VM thread should exit at Safepoint"); 920 VMThread::destroy(); 921 } 922 923 // Now, all Java threads are gone except daemon threads. Daemon threads 924 // running Java code or in VM are stopped by the Safepoint. However, 925 // daemon threads executing native code are still running. But they 926 // will be stopped at native=>Java/VM barriers. Note that we can't 927 // simply kill or suspend them, as it is inherently deadlock-prone. 928 929 VM_Exit::set_vm_exited(); 930 931 // Clean up ideal graph printers after the VMThread has started 932 // the final safepoint which will block all the Compiler threads. 933 // Note that this Thread has already logically exited so the 934 // clean_up() function's use of a JavaThreadIteratorWithHandle 935 // would be a problem except set_vm_exited() has remembered the 936 // shutdown thread which is granted a policy exception. 937 #if defined(COMPILER2) && !defined(PRODUCT) 938 IdealGraphPrinter::clean_up(); 939 #endif 940 941 notify_vm_shutdown(); 942 943 // exit_globals() will delete tty 944 exit_globals(); 945 946 // Deleting the shutdown thread here is safe. See comment on 947 // wait_until_not_protected() above. 948 delete thread; 949 950 #if INCLUDE_JVMCI 951 if (JVMCICounterSize > 0) { 952 FREE_C_HEAP_ARRAY(jlong, JavaThread::_jvmci_old_thread_counters); 953 } 954 #endif 955 956 LogConfiguration::finalize(); 957 } 958 959 960 jboolean Threads::is_supported_jni_version_including_1_1(jint version) { 961 if (version == JNI_VERSION_1_1) return JNI_TRUE; 962 return is_supported_jni_version(version); 963 } 964 965 966 jboolean Threads::is_supported_jni_version(jint version) { 967 if (version == JNI_VERSION_1_2) return JNI_TRUE; 968 if (version == JNI_VERSION_1_4) return JNI_TRUE; 969 if (version == JNI_VERSION_1_6) return JNI_TRUE; 970 if (version == JNI_VERSION_1_8) return JNI_TRUE; 971 if (version == JNI_VERSION_9) return JNI_TRUE; 972 if (version == JNI_VERSION_10) return JNI_TRUE; 973 if (version == JNI_VERSION_19) return JNI_TRUE; 974 if (version == JNI_VERSION_20) return JNI_TRUE; 975 if (version == JNI_VERSION_21) return JNI_TRUE; 976 return JNI_FALSE; 977 } 978 979 void Threads::add(JavaThread* p, bool force_daemon) { 980 // The threads lock must be owned at this point 981 assert(Threads_lock->owned_by_self(), "must have threads lock"); 982 983 BarrierSet::barrier_set()->on_thread_attach(p); 984 985 // Once a JavaThread is added to the Threads list, smr_delete() has 986 // to be used to delete it. Otherwise we can just delete it directly. 987 p->set_on_thread_list(); 988 989 _number_of_threads++; 990 oop threadObj = p->threadObj(); 991 bool daemon = true; 992 // Bootstrapping problem: threadObj can be null for initial 993 // JavaThread (or for threads attached via JNI) 994 if (!force_daemon && 995 (threadObj == nullptr || !java_lang_Thread::is_daemon(threadObj))) { 996 _number_of_non_daemon_threads++; 997 daemon = false; 998 } 999 1000 ThreadService::add_thread(p, daemon); 1001 1002 // Maintain fast thread list 1003 ThreadsSMRSupport::add_thread(p); 1004 1005 // Increase the ObjectMonitor ceiling for the new thread. 1006 ObjectSynchronizer::inc_in_use_list_ceiling(); 1007 1008 // Possible GC point. 1009 Events::log(p, "Thread added: " INTPTR_FORMAT, p2i(p)); 1010 1011 // Make new thread known to active EscapeBarrier 1012 EscapeBarrier::thread_added(p); 1013 } 1014 1015 void Threads::remove(JavaThread* p, bool is_daemon) { 1016 // Extra scope needed for Thread_lock, so we can check 1017 // that we do not remove thread without safepoint code notice 1018 { MonitorLocker ml(Threads_lock); 1019 1020 if (ThreadIdTable::is_initialized()) { 1021 // This cleanup must be done before the current thread's GC barrier 1022 // is detached since we need to touch the threadObj oop. 1023 jlong tid = SharedRuntime::get_java_tid(p); 1024 ThreadIdTable::remove_thread(tid); 1025 } 1026 1027 // BarrierSet state must be destroyed after the last thread transition 1028 // before the thread terminates. Thread transitions result in calls to 1029 // StackWatermarkSet::on_safepoint(), which performs GC processing, 1030 // requiring the GC state to be alive. 1031 BarrierSet::barrier_set()->on_thread_detach(p); 1032 if (p->is_exiting()) { 1033 // If we got here via JavaThread::exit(), then we remember that the 1034 // thread's GC barrier has been detached. We don't do this when we get 1035 // here from another path, e.g., cleanup_failed_attach_current_thread(). 1036 p->set_terminated(JavaThread::_thread_gc_barrier_detached); 1037 } 1038 1039 assert(ThreadsSMRSupport::get_java_thread_list()->includes(p), "p must be present"); 1040 1041 // Maintain fast thread list 1042 ThreadsSMRSupport::remove_thread(p); 1043 1044 _number_of_threads--; 1045 if (!is_daemon) { 1046 _number_of_non_daemon_threads--; 1047 1048 // If this is the last non-daemon thread then we need to do 1049 // a notify on the Threads_lock so a thread waiting 1050 // on destroy_vm will wake up. But that thread could be a daemon 1051 // or non-daemon, so we notify for both the 0 and 1 case. 1052 if (number_of_non_daemon_threads() <= 1) { 1053 ml.notify_all(); 1054 } 1055 } 1056 ThreadService::remove_thread(p, is_daemon); 1057 1058 // Make sure that safepoint code disregard this thread. This is needed since 1059 // the thread might mess around with locks after this point. This can cause it 1060 // to do callbacks into the safepoint code. However, the safepoint code is not aware 1061 // of this thread since it is removed from the queue. 1062 p->set_terminated(JavaThread::_thread_terminated); 1063 1064 // Notify threads waiting in EscapeBarriers 1065 EscapeBarrier::thread_removed(p); 1066 } // unlock Threads_lock 1067 1068 // Reduce the ObjectMonitor ceiling for the exiting thread. 1069 ObjectSynchronizer::dec_in_use_list_ceiling(); 1070 1071 // Since Events::log uses a lock, we grab it outside the Threads_lock 1072 Events::log(p, "Thread exited: " INTPTR_FORMAT, p2i(p)); 1073 } 1074 1075 // Operations on the Threads list for GC. These are not explicitly locked, 1076 // but the garbage collector must provide a safe context for them to run. 1077 // In particular, these things should never be called when the Threads_lock 1078 // is held by some other thread. (Note: the Safepoint abstraction also 1079 // uses the Threads_lock to guarantee this property. It also makes sure that 1080 // all threads gets blocked when exiting or starting). 1081 1082 void Threads::oops_do(OopClosure* f, CodeBlobClosure* cf) { 1083 ALL_JAVA_THREADS(p) { 1084 p->oops_do(f, cf); 1085 } 1086 VMThread::vm_thread()->oops_do(f, cf); 1087 } 1088 1089 void Threads::change_thread_claim_token() { 1090 if (++_thread_claim_token == 0) { 1091 // On overflow of the token counter, there is a risk of future 1092 // collisions between a new global token value and a stale token 1093 // for a thread, because not all iterations visit all threads. 1094 // (Though it's pretty much a theoretical concern for non-trivial 1095 // token counter sizes.) To deal with the possibility, reset all 1096 // the thread tokens to zero on global token overflow. 1097 struct ResetClaims : public ThreadClosure { 1098 virtual void do_thread(Thread* t) { 1099 t->claim_threads_do(false, 0); 1100 } 1101 } reset_claims; 1102 Threads::threads_do(&reset_claims); 1103 // On overflow, update the global token to non-zero, to 1104 // avoid the special "never claimed" initial thread value. 1105 _thread_claim_token = 1; 1106 } 1107 } 1108 1109 #ifdef ASSERT 1110 void assert_thread_claimed(const char* kind, Thread* t, uintx expected) { 1111 const uintx token = t->threads_do_token(); 1112 assert(token == expected, 1113 "%s " PTR_FORMAT " has incorrect value " UINTX_FORMAT " != " 1114 UINTX_FORMAT, kind, p2i(t), token, expected); 1115 } 1116 1117 void Threads::assert_all_threads_claimed() { 1118 ALL_JAVA_THREADS(p) { 1119 assert_thread_claimed("JavaThread", p, _thread_claim_token); 1120 } 1121 1122 struct NJTClaimedVerifierClosure : public ThreadClosure { 1123 uintx _thread_claim_token; 1124 1125 NJTClaimedVerifierClosure(uintx thread_claim_token) : ThreadClosure(), _thread_claim_token(thread_claim_token) { } 1126 1127 virtual void do_thread(Thread* thread) override { 1128 assert_thread_claimed("Non-JavaThread", VMThread::vm_thread(), _thread_claim_token); 1129 } 1130 } tc(_thread_claim_token); 1131 1132 non_java_threads_do(&tc); 1133 } 1134 #endif // ASSERT 1135 1136 class ParallelOopsDoThreadClosure : public ThreadClosure { 1137 private: 1138 OopClosure* _f; 1139 CodeBlobClosure* _cf; 1140 public: 1141 ParallelOopsDoThreadClosure(OopClosure* f, CodeBlobClosure* cf) : _f(f), _cf(cf) {} 1142 void do_thread(Thread* t) { 1143 t->oops_do(_f, _cf); 1144 } 1145 }; 1146 1147 void Threads::possibly_parallel_oops_do(bool is_par, OopClosure* f, CodeBlobClosure* cf) { 1148 ParallelOopsDoThreadClosure tc(f, cf); 1149 possibly_parallel_threads_do(is_par, &tc); 1150 } 1151 1152 void Threads::metadata_do(MetadataClosure* f) { 1153 ALL_JAVA_THREADS(p) { 1154 p->metadata_do(f); 1155 } 1156 } 1157 1158 class ThreadHandlesClosure : public ThreadClosure { 1159 void (*_f)(Metadata*); 1160 public: 1161 ThreadHandlesClosure(void f(Metadata*)) : _f(f) {} 1162 virtual void do_thread(Thread* thread) { 1163 thread->metadata_handles_do(_f); 1164 } 1165 }; 1166 1167 void Threads::metadata_handles_do(void f(Metadata*)) { 1168 // Only walk the Handles in Thread. 1169 ThreadHandlesClosure handles_closure(f); 1170 threads_do(&handles_closure); 1171 } 1172 1173 // Get count Java threads that are waiting to enter the specified monitor. 1174 GrowableArray<JavaThread*>* Threads::get_pending_threads(ThreadsList * t_list, 1175 int count, 1176 address monitor) { 1177 GrowableArray<JavaThread*>* result = new GrowableArray<JavaThread*>(count); 1178 1179 int i = 0; 1180 for (JavaThread* p : *t_list) { 1181 if (!p->can_call_java()) continue; 1182 1183 // The first stage of async deflation does not affect any field 1184 // used by this comparison so the ObjectMonitor* is usable here. 1185 address pending = (address)p->current_pending_monitor(); 1186 if (pending == monitor) { // found a match 1187 if (i < count) result->append(p); // save the first count matches 1188 i++; 1189 } 1190 } 1191 1192 return result; 1193 } 1194 1195 1196 JavaThread *Threads::owning_thread_from_monitor_owner(ThreadsList * t_list, 1197 address owner) { 1198 assert(LockingMode != LM_LIGHTWEIGHT, "Not with new lightweight locking"); 1199 // null owner means not locked so we can skip the search 1200 if (owner == nullptr) return nullptr; 1201 1202 for (JavaThread* p : *t_list) { 1203 // first, see if owner is the address of a Java thread 1204 if (owner == (address)p) return p; 1205 } 1206 1207 // Cannot assert on lack of success here since this function may be 1208 // used by code that is trying to report useful problem information 1209 // like deadlock detection. 1210 if (LockingMode == LM_MONITOR) return nullptr; 1211 1212 // If we didn't find a matching Java thread and we didn't force use of 1213 // heavyweight monitors, then the owner is the stack address of the 1214 // Lock Word in the owning Java thread's stack. 1215 // 1216 JavaThread* the_owner = nullptr; 1217 for (JavaThread* q : *t_list) { 1218 if (q->is_lock_owned(owner)) { 1219 the_owner = q; 1220 break; 1221 } 1222 } 1223 1224 // cannot assert on lack of success here; see above comment 1225 return the_owner; 1226 } 1227 1228 JavaThread* Threads::owning_thread_from_object(ThreadsList * t_list, oop obj) { 1229 assert(LockingMode == LM_LIGHTWEIGHT, "Only with new lightweight locking"); 1230 for (JavaThread* q : *t_list) { 1231 if (q->lock_stack().contains(obj)) { 1232 return q; 1233 } 1234 } 1235 return nullptr; 1236 } 1237 1238 JavaThread* Threads::owning_thread_from_monitor(ThreadsList* t_list, ObjectMonitor* monitor) { 1239 if (LockingMode == LM_LIGHTWEIGHT) { 1240 if (monitor->is_owner_anonymous()) { 1241 return owning_thread_from_object(t_list, monitor->object()); 1242 } else { 1243 Thread* owner = reinterpret_cast<Thread*>(monitor->owner()); 1244 assert(owner == nullptr || owner->is_Java_thread(), "only JavaThreads own monitors"); 1245 return reinterpret_cast<JavaThread*>(owner); 1246 } 1247 } else { 1248 address owner = (address)monitor->owner(); 1249 return owning_thread_from_monitor_owner(t_list, owner); 1250 } 1251 } 1252 1253 class PrintOnClosure : public ThreadClosure { 1254 private: 1255 outputStream* _st; 1256 1257 public: 1258 PrintOnClosure(outputStream* st) : 1259 _st(st) {} 1260 1261 virtual void do_thread(Thread* thread) { 1262 if (thread != nullptr) { 1263 thread->print_on(_st); 1264 _st->cr(); 1265 } 1266 } 1267 }; 1268 1269 // Threads::print_on() is called at safepoint by VM_PrintThreads operation. 1270 void Threads::print_on(outputStream* st, bool print_stacks, 1271 bool internal_format, bool print_concurrent_locks, 1272 bool print_extended_info) { 1273 char buf[32]; 1274 st->print_raw_cr(os::local_time_string(buf, sizeof(buf))); 1275 1276 st->print_cr("Full thread dump %s (%s %s):", 1277 VM_Version::vm_name(), 1278 VM_Version::vm_release(), 1279 VM_Version::vm_info_string()); 1280 st->cr(); 1281 1282 #if INCLUDE_SERVICES 1283 // Dump concurrent locks 1284 ConcurrentLocksDump concurrent_locks; 1285 if (print_concurrent_locks) { 1286 concurrent_locks.dump_at_safepoint(); 1287 } 1288 #endif // INCLUDE_SERVICES 1289 1290 ThreadsSMRSupport::print_info_on(st); 1291 st->cr(); 1292 1293 ALL_JAVA_THREADS(p) { 1294 ResourceMark rm; 1295 p->print_on(st, print_extended_info); 1296 if (print_stacks) { 1297 if (internal_format) { 1298 p->trace_stack(); 1299 } else { 1300 p->print_stack_on(st); 1301 } 1302 } 1303 st->cr(); 1304 #if INCLUDE_SERVICES 1305 if (print_concurrent_locks) { 1306 concurrent_locks.print_locks_on(p, st); 1307 } 1308 #endif // INCLUDE_SERVICES 1309 } 1310 1311 PrintOnClosure cl(st); 1312 cl.do_thread(VMThread::vm_thread()); 1313 Universe::heap()->gc_threads_do(&cl); 1314 cl.do_thread(WatcherThread::watcher_thread()); 1315 cl.do_thread(AsyncLogWriter::instance()); 1316 1317 st->flush(); 1318 } 1319 1320 void Threads::print_on_error(Thread* this_thread, outputStream* st, Thread* current, char* buf, 1321 int buflen, bool* found_current) { 1322 if (this_thread != nullptr) { 1323 bool is_current = (current == this_thread); 1324 *found_current = *found_current || is_current; 1325 st->print("%s", is_current ? "=>" : " "); 1326 1327 st->print(PTR_FORMAT, p2i(this_thread)); 1328 st->print(" "); 1329 this_thread->print_on_error(st, buf, buflen); 1330 st->cr(); 1331 } 1332 } 1333 1334 class PrintOnErrorClosure : public ThreadClosure { 1335 outputStream* _st; 1336 Thread* _current; 1337 char* _buf; 1338 int _buflen; 1339 bool* _found_current; 1340 unsigned _num_printed; 1341 public: 1342 PrintOnErrorClosure(outputStream* st, Thread* current, char* buf, 1343 int buflen, bool* found_current) : 1344 _st(st), _current(current), _buf(buf), _buflen(buflen), _found_current(found_current), 1345 _num_printed(0) {} 1346 1347 virtual void do_thread(Thread* thread) { 1348 _num_printed++; 1349 Threads::print_on_error(thread, _st, _current, _buf, _buflen, _found_current); 1350 } 1351 1352 unsigned num_printed() const { return _num_printed; } 1353 }; 1354 1355 // Threads::print_on_error() is called by fatal error handler. It's possible 1356 // that VM is not at safepoint and/or current thread is inside signal handler. 1357 // Don't print stack trace, as the stack may not be walkable. Don't allocate 1358 // memory (even in resource area), it might deadlock the error handler. 1359 void Threads::print_on_error(outputStream* st, Thread* current, char* buf, 1360 int buflen) { 1361 ThreadsSMRSupport::print_info_on(st); 1362 st->cr(); 1363 1364 bool found_current = false; 1365 st->print_cr("Java Threads: ( => current thread )"); 1366 unsigned num_java = 0; 1367 ALL_JAVA_THREADS(thread) { 1368 print_on_error(thread, st, current, buf, buflen, &found_current); 1369 num_java++; 1370 } 1371 st->print_cr("Total: %u", num_java); 1372 st->cr(); 1373 1374 st->print_cr("Other Threads:"); 1375 unsigned num_other = ((VMThread::vm_thread() != nullptr) ? 1 : 0) + 1376 ((WatcherThread::watcher_thread() != nullptr) ? 1 : 0) + 1377 ((AsyncLogWriter::instance() != nullptr) ? 1 : 0); 1378 print_on_error(VMThread::vm_thread(), st, current, buf, buflen, &found_current); 1379 print_on_error(WatcherThread::watcher_thread(), st, current, buf, buflen, &found_current); 1380 print_on_error(AsyncLogWriter::instance(), st, current, buf, buflen, &found_current); 1381 1382 if (Universe::heap() != nullptr) { 1383 PrintOnErrorClosure print_closure(st, current, buf, buflen, &found_current); 1384 Universe::heap()->gc_threads_do(&print_closure); 1385 num_other += print_closure.num_printed(); 1386 } 1387 1388 if (!found_current) { 1389 st->cr(); 1390 st->print("=>" PTR_FORMAT " (exited) ", p2i(current)); 1391 current->print_on_error(st, buf, buflen); 1392 num_other++; 1393 st->cr(); 1394 } 1395 st->print_cr("Total: %u", num_other); 1396 st->cr(); 1397 1398 st->print_cr("Threads with active compile tasks:"); 1399 unsigned num = print_threads_compiling(st, buf, buflen); 1400 st->print_cr("Total: %u", num); 1401 } 1402 1403 unsigned Threads::print_threads_compiling(outputStream* st, char* buf, int buflen, bool short_form) { 1404 unsigned num = 0; 1405 ALL_JAVA_THREADS(thread) { 1406 if (thread->is_Compiler_thread()) { 1407 CompilerThread* ct = (CompilerThread*) thread; 1408 1409 // Keep task in local variable for null check. 1410 // ct->_task might be set to null by concurring compiler thread 1411 // because it completed the compilation. The task is never freed, 1412 // though, just returned to a free list. 1413 CompileTask* task = ct->task(); 1414 if (task != nullptr) { 1415 thread->print_name_on_error(st, buf, buflen); 1416 st->print(" "); 1417 task->print(st, nullptr, short_form, true); 1418 num++; 1419 } 1420 } 1421 } 1422 return num; 1423 } 1424 1425 void Threads::verify() { 1426 ALL_JAVA_THREADS(p) { 1427 p->verify(); 1428 } 1429 VMThread* thread = VMThread::vm_thread(); 1430 if (thread != nullptr) thread->verify(); 1431 }