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