1 /* 2 * Copyright (c) 1997, 2022, 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/dynamicArchive.hpp" 28 #include "ci/ciEnv.hpp" 29 #include "classfile/javaClasses.inline.hpp" 30 #include "classfile/javaThreadStatus.hpp" 31 #include "classfile/systemDictionary.hpp" 32 #include "classfile/vmClasses.hpp" 33 #include "classfile/vmSymbols.hpp" 34 #include "code/codeCache.hpp" 35 #include "code/scopeDesc.hpp" 36 #include "compiler/compileTask.hpp" 37 #include "compiler/compilerThread.hpp" 38 #include "gc/shared/oopStorage.hpp" 39 #include "gc/shared/oopStorageSet.hpp" 40 #include "gc/shared/tlab_globals.hpp" 41 #include "jfr/jfrEvents.hpp" 42 #include "jvm.h" 43 #include "jvmtifiles/jvmtiEnv.hpp" 44 #include "logging/log.hpp" 45 #include "logging/logAsyncWriter.hpp" 46 #include "logging/logStream.hpp" 47 #include "memory/allocation.inline.hpp" 48 #include "memory/iterator.hpp" 49 #include "memory/universe.hpp" 50 #include "oops/access.inline.hpp" 51 #include "oops/instanceKlass.hpp" 52 #include "oops/klass.inline.hpp" 53 #include "oops/oop.inline.hpp" 54 #include "oops/oopHandle.inline.hpp" 55 #include "oops/verifyOopClosure.hpp" 56 #include "prims/jvm_misc.hpp" 57 #include "prims/jvmtiDeferredUpdates.hpp" 58 #include "prims/jvmtiExport.hpp" 59 #include "prims/jvmtiThreadState.inline.hpp" 60 #include "runtime/atomic.hpp" 61 #include "runtime/continuation.hpp" 62 #include "runtime/continuationEntry.inline.hpp" 63 #include "runtime/continuationHelper.inline.hpp" 64 #include "runtime/deoptimization.hpp" 65 #include "runtime/frame.inline.hpp" 66 #include "runtime/handles.inline.hpp" 67 #include "runtime/handshake.hpp" 68 #include "runtime/interfaceSupport.inline.hpp" 69 #include "runtime/java.hpp" 70 #include "runtime/javaCalls.hpp" 71 #include "runtime/javaThread.inline.hpp" 72 #include "runtime/jniHandles.inline.hpp" 73 #include "runtime/mutexLocker.hpp" 74 #include "runtime/orderAccess.hpp" 75 #include "runtime/osThread.hpp" 76 #include "runtime/safepoint.hpp" 77 #include "runtime/safepointMechanism.inline.hpp" 78 #include "runtime/safepointVerifiers.hpp" 79 #include "runtime/serviceThread.hpp" 80 #include "runtime/stackFrameStream.inline.hpp" 81 #include "runtime/stackWatermarkSet.hpp" 82 #include "runtime/synchronizer.hpp" 83 #include "runtime/threadCritical.hpp" 84 #include "runtime/threadSMR.inline.hpp" 85 #include "runtime/threadStatisticalInfo.hpp" 86 #include "runtime/threadWXSetters.inline.hpp" 87 #include "runtime/timer.hpp" 88 #include "runtime/timerTrace.hpp" 89 #include "runtime/vframe.inline.hpp" 90 #include "runtime/vframeArray.hpp" 91 #include "runtime/vframe_hp.hpp" 92 #include "runtime/vmThread.hpp" 93 #include "runtime/vmOperations.hpp" 94 #include "services/threadService.hpp" 95 #include "utilities/copy.hpp" 96 #include "utilities/defaultStream.hpp" 97 #include "utilities/dtrace.hpp" 98 #include "utilities/events.hpp" 99 #include "utilities/macros.hpp" 100 #include "utilities/preserveException.hpp" 101 #include "utilities/spinYield.hpp" 102 #if INCLUDE_JVMCI 103 #include "jvmci/jvmci.hpp" 104 #include "jvmci/jvmciEnv.hpp" 105 #endif 106 #if INCLUDE_JFR 107 #include "jfr/jfr.hpp" 108 #endif 109 110 // Set by os layer. 111 size_t JavaThread::_stack_size_at_create = 0; 112 113 #ifdef DTRACE_ENABLED 114 115 // Only bother with this argument setup if dtrace is available 116 117 #define HOTSPOT_THREAD_PROBE_start HOTSPOT_THREAD_START 118 #define HOTSPOT_THREAD_PROBE_stop HOTSPOT_THREAD_STOP 119 120 #define DTRACE_THREAD_PROBE(probe, javathread) \ 121 { \ 122 ResourceMark rm(this); \ 123 int len = 0; \ 124 const char* name = (javathread)->name(); \ 125 len = strlen(name); \ 126 HOTSPOT_THREAD_PROBE_##probe(/* probe = start, stop */ \ 127 (char *) name, len, \ 128 java_lang_Thread::thread_id((javathread)->threadObj()), \ 129 (uintptr_t) (javathread)->osthread()->thread_id(), \ 130 java_lang_Thread::is_daemon((javathread)->threadObj())); \ 131 } 132 133 #else // ndef DTRACE_ENABLED 134 135 #define DTRACE_THREAD_PROBE(probe, javathread) 136 137 #endif // ndef DTRACE_ENABLED 138 139 void JavaThread::smr_delete() { 140 if (_on_thread_list) { 141 ThreadsSMRSupport::smr_delete(this); 142 } else { 143 delete this; 144 } 145 } 146 147 // Initialized by VMThread at vm_global_init 148 OopStorage* JavaThread::_thread_oop_storage = NULL; 149 150 OopStorage* JavaThread::thread_oop_storage() { 151 assert(_thread_oop_storage != NULL, "not yet initialized"); 152 return _thread_oop_storage; 153 } 154 155 void JavaThread::set_threadOopHandles(oop p) { 156 assert(_thread_oop_storage != NULL, "not yet initialized"); 157 _threadObj = OopHandle(_thread_oop_storage, p); 158 _vthread = OopHandle(_thread_oop_storage, p); 159 _jvmti_vthread = OopHandle(_thread_oop_storage, NULL); 160 _scopedValueCache = OopHandle(_thread_oop_storage, NULL); 161 } 162 163 oop JavaThread::threadObj() const { 164 // Ideally we would verify the current thread is oop_safe when this is called, but as we can 165 // be called from a signal handler we would have to use Thread::current_or_null_safe(). That 166 // has overhead and also interacts poorly with GetLastError on Windows due to the use of TLS. 167 // Instead callers must verify oop safe access. 168 return _threadObj.resolve(); 169 } 170 171 oop JavaThread::vthread() const { 172 return _vthread.resolve(); 173 } 174 175 void JavaThread::set_vthread(oop p) { 176 assert(_thread_oop_storage != NULL, "not yet initialized"); 177 _vthread.replace(p); 178 } 179 180 oop JavaThread::jvmti_vthread() const { 181 return _jvmti_vthread.resolve(); 182 } 183 184 void JavaThread::set_jvmti_vthread(oop p) { 185 assert(_thread_oop_storage != NULL, "not yet initialized"); 186 _jvmti_vthread.replace(p); 187 } 188 189 oop JavaThread::scopedValueCache() const { 190 return _scopedValueCache.resolve(); 191 } 192 193 void JavaThread::set_scopedValueCache(oop p) { 194 if (_scopedValueCache.ptr_raw() != NULL) { // i.e. if the OopHandle has been allocated 195 _scopedValueCache.replace(p); 196 } else { 197 assert(p == NULL, "not yet initialized"); 198 } 199 } 200 201 void JavaThread::clear_scopedValueBindings() { 202 set_scopedValueCache(NULL); 203 oop vthread_oop = vthread(); 204 // vthread may be null here if we get a VM error during startup, 205 // before the java.lang.Thread instance has been created. 206 if (vthread_oop != NULL) { 207 java_lang_Thread::clear_scopedValueBindings(vthread_oop); 208 } 209 } 210 211 void JavaThread::allocate_threadObj(Handle thread_group, const char* thread_name, 212 bool daemon, TRAPS) { 213 assert(thread_group.not_null(), "thread group should be specified"); 214 assert(threadObj() == NULL, "should only create Java thread object once"); 215 216 InstanceKlass* ik = vmClasses::Thread_klass(); 217 assert(ik->is_initialized(), "must be"); 218 instanceHandle thread_oop = ik->allocate_instance_handle(CHECK); 219 220 // We are called from jni_AttachCurrentThread/jni_AttachCurrentThreadAsDaemon. 221 // We cannot use JavaCalls::construct_new_instance because the java.lang.Thread 222 // constructor calls Thread.current(), which must be set here. 223 java_lang_Thread::set_thread(thread_oop(), this); 224 set_threadOopHandles(thread_oop()); 225 226 JavaValue result(T_VOID); 227 if (thread_name != NULL) { 228 Handle name = java_lang_String::create_from_str(thread_name, CHECK); 229 // Thread gets assigned specified name and null target 230 JavaCalls::call_special(&result, 231 thread_oop, 232 ik, 233 vmSymbols::object_initializer_name(), 234 vmSymbols::threadgroup_string_void_signature(), 235 thread_group, 236 name, 237 THREAD); 238 } else { 239 // Thread gets assigned name "Thread-nnn" and null target 240 // (java.lang.Thread doesn't have a constructor taking only a ThreadGroup argument) 241 JavaCalls::call_special(&result, 242 thread_oop, 243 ik, 244 vmSymbols::object_initializer_name(), 245 vmSymbols::threadgroup_runnable_void_signature(), 246 thread_group, 247 Handle(), 248 THREAD); 249 } 250 os::set_priority(this, NormPriority); 251 252 if (daemon) { 253 java_lang_Thread::set_daemon(thread_oop()); 254 } 255 } 256 257 // ======= JavaThread ======== 258 259 #if INCLUDE_JVMCI 260 261 jlong* JavaThread::_jvmci_old_thread_counters; 262 263 bool jvmci_counters_include(JavaThread* thread) { 264 return !JVMCICountersExcludeCompiler || !thread->is_Compiler_thread(); 265 } 266 267 void JavaThread::collect_counters(jlong* array, int length) { 268 assert(length == JVMCICounterSize, "wrong value"); 269 for (int i = 0; i < length; i++) { 270 array[i] = _jvmci_old_thread_counters[i]; 271 } 272 for (JavaThread* tp : ThreadsListHandle()) { 273 if (jvmci_counters_include(tp)) { 274 for (int i = 0; i < length; i++) { 275 array[i] += tp->_jvmci_counters[i]; 276 } 277 } 278 } 279 } 280 281 // Attempt to enlarge the array for per thread counters. 282 jlong* resize_counters_array(jlong* old_counters, int current_size, int new_size) { 283 jlong* new_counters = NEW_C_HEAP_ARRAY_RETURN_NULL(jlong, new_size, mtJVMCI); 284 if (new_counters == NULL) { 285 return NULL; 286 } 287 if (old_counters == NULL) { 288 old_counters = new_counters; 289 memset(old_counters, 0, sizeof(jlong) * new_size); 290 } else { 291 for (int i = 0; i < MIN2((int) current_size, new_size); i++) { 292 new_counters[i] = old_counters[i]; 293 } 294 if (new_size > current_size) { 295 memset(new_counters + current_size, 0, sizeof(jlong) * (new_size - current_size)); 296 } 297 FREE_C_HEAP_ARRAY(jlong, old_counters); 298 } 299 return new_counters; 300 } 301 302 // Attempt to enlarge the array for per thread counters. 303 bool JavaThread::resize_counters(int current_size, int new_size) { 304 jlong* new_counters = resize_counters_array(_jvmci_counters, current_size, new_size); 305 if (new_counters == NULL) { 306 return false; 307 } else { 308 _jvmci_counters = new_counters; 309 return true; 310 } 311 } 312 313 class VM_JVMCIResizeCounters : public VM_Operation { 314 private: 315 int _new_size; 316 bool _failed; 317 318 public: 319 VM_JVMCIResizeCounters(int new_size) : _new_size(new_size), _failed(false) { } 320 VMOp_Type type() const { return VMOp_JVMCIResizeCounters; } 321 bool allow_nested_vm_operations() const { return true; } 322 void doit() { 323 // Resize the old thread counters array 324 jlong* new_counters = resize_counters_array(JavaThread::_jvmci_old_thread_counters, JVMCICounterSize, _new_size); 325 if (new_counters == NULL) { 326 _failed = true; 327 return; 328 } else { 329 JavaThread::_jvmci_old_thread_counters = new_counters; 330 } 331 332 // Now resize each threads array 333 for (JavaThread* tp : ThreadsListHandle()) { 334 if (!tp->resize_counters(JVMCICounterSize, _new_size)) { 335 _failed = true; 336 break; 337 } 338 } 339 if (!_failed) { 340 JVMCICounterSize = _new_size; 341 } 342 } 343 344 bool failed() { return _failed; } 345 }; 346 347 bool JavaThread::resize_all_jvmci_counters(int new_size) { 348 VM_JVMCIResizeCounters op(new_size); 349 VMThread::execute(&op); 350 return !op.failed(); 351 } 352 353 #endif // INCLUDE_JVMCI 354 355 #ifdef ASSERT 356 // Checks safepoint allowed and clears unhandled oops at potential safepoints. 357 void JavaThread::check_possible_safepoint() { 358 if (_no_safepoint_count > 0) { 359 print_owned_locks(); 360 assert(false, "Possible safepoint reached by thread that does not allow it"); 361 } 362 #ifdef CHECK_UNHANDLED_OOPS 363 // Clear unhandled oops in JavaThreads so we get a crash right away. 364 clear_unhandled_oops(); 365 #endif // CHECK_UNHANDLED_OOPS 366 367 // Macos/aarch64 should be in the right state for safepoint (e.g. 368 // deoptimization needs WXWrite). Crashes caused by the wrong state rarely 369 // happens in practice, making such issues hard to find and reproduce. 370 #if defined(__APPLE__) && defined(AARCH64) 371 if (AssertWXAtThreadSync) { 372 assert_wx_state(WXWrite); 373 } 374 #endif 375 } 376 377 void JavaThread::check_for_valid_safepoint_state() { 378 // Check NoSafepointVerifier, which is implied by locks taken that can be 379 // shared with the VM thread. This makes sure that no locks with allow_vm_block 380 // are held. 381 check_possible_safepoint(); 382 383 if (thread_state() != _thread_in_vm) { 384 fatal("LEAF method calling lock?"); 385 } 386 387 if (GCALotAtAllSafepoints) { 388 // We could enter a safepoint here and thus have a gc 389 InterfaceSupport::check_gc_alot(); 390 } 391 } 392 #endif // ASSERT 393 394 // A JavaThread is a normal Java thread 395 396 JavaThread::JavaThread() : 397 // Initialize fields 398 399 _on_thread_list(false), 400 DEBUG_ONLY(_java_call_counter(0) COMMA) 401 _entry_point(nullptr), 402 _deopt_mark(nullptr), 403 _deopt_nmethod(nullptr), 404 _vframe_array_head(nullptr), 405 _vframe_array_last(nullptr), 406 _jvmti_deferred_updates(nullptr), 407 _callee_target(nullptr), 408 _vm_result(nullptr), 409 _vm_result_2(nullptr), 410 411 _current_pending_monitor(NULL), 412 _current_pending_monitor_is_from_java(true), 413 _current_waiting_monitor(NULL), 414 _active_handles(NULL), 415 _free_handle_block(NULL), 416 _Stalled(0), 417 418 _monitor_chunks(nullptr), 419 420 _suspend_flags(0), 421 422 _thread_state(_thread_new), 423 _saved_exception_pc(nullptr), 424 #ifdef ASSERT 425 _no_safepoint_count(0), 426 _visited_for_critical_count(false), 427 #endif 428 429 _terminated(_not_terminated), 430 _in_deopt_handler(0), 431 _doing_unsafe_access(false), 432 _do_not_unlock_if_synchronized(false), 433 #if INCLUDE_JVMTI 434 _carrier_thread_suspended(false), 435 _is_in_VTMS_transition(false), 436 _is_in_tmp_VTMS_transition(false), 437 #ifdef ASSERT 438 _is_VTMS_transition_disabler(false), 439 #endif 440 #endif 441 _jni_attach_state(_not_attaching_via_jni), 442 #if INCLUDE_JVMCI 443 _pending_deoptimization(-1), 444 _pending_monitorenter(false), 445 _pending_transfer_to_interpreter(false), 446 _in_retryable_allocation(false), 447 _pending_failed_speculation(0), 448 _jvmci{nullptr}, 449 _libjvmci_runtime(nullptr), 450 _jvmci_counters(nullptr), 451 _jvmci_reserved0(0), 452 _jvmci_reserved1(0), 453 _jvmci_reserved_oop0(nullptr), 454 #endif // INCLUDE_JVMCI 455 456 _exception_oop(oop()), 457 _exception_pc(0), 458 _exception_handler_pc(0), 459 _is_method_handle_return(0), 460 461 _jni_active_critical(0), 462 _pending_jni_exception_check_fn(nullptr), 463 _depth_first_number(0), 464 465 // JVMTI PopFrame support 466 _popframe_condition(popframe_inactive), 467 _frames_to_pop_failed_realloc(0), 468 469 _cont_entry(nullptr), 470 _cont_fastpath(0), 471 _cont_fastpath_thread_state(1), 472 _held_monitor_count(0), 473 _jni_monitor_count(0), 474 475 _handshake(this), 476 477 _popframe_preserved_args(nullptr), 478 _popframe_preserved_args_size(0), 479 480 _jvmti_thread_state(nullptr), 481 _interp_only_mode(0), 482 _should_post_on_exceptions_flag(JNI_FALSE), 483 _thread_stat(new ThreadStatistics()), 484 485 _parker(), 486 487 _class_to_be_initialized(nullptr), 488 489 _SleepEvent(ParkEvent::Allocate(this)) 490 { 491 set_jni_functions(jni_functions()); 492 493 #if INCLUDE_JVMCI 494 assert(_jvmci._implicit_exception_pc == nullptr, "must be"); 495 if (JVMCICounterSize > 0) { 496 resize_counters(0, (int) JVMCICounterSize); 497 } 498 #endif // INCLUDE_JVMCI 499 500 // Setup safepoint state info for this thread 501 ThreadSafepointState::create(this); 502 503 SafepointMechanism::initialize_header(this); 504 505 set_requires_cross_modify_fence(false); 506 507 pd_initialize(); 508 assert(deferred_card_mark().is_empty(), "Default MemRegion ctor"); 509 } 510 511 JavaThread::JavaThread(bool is_attaching_via_jni) : JavaThread() { 512 if (is_attaching_via_jni) { 513 _jni_attach_state = _attaching_via_jni; 514 } 515 } 516 517 518 // interrupt support 519 520 void JavaThread::interrupt() { 521 // All callers should have 'this' thread protected by a 522 // ThreadsListHandle so that it cannot terminate and deallocate 523 // itself. 524 debug_only(check_for_dangling_thread_pointer(this);) 525 526 // For Windows _interrupt_event 527 WINDOWS_ONLY(osthread()->set_interrupted(true);) 528 529 // For Thread.sleep 530 _SleepEvent->unpark(); 531 532 // For JSR166 LockSupport.park 533 parker()->unpark(); 534 535 // For ObjectMonitor and JvmtiRawMonitor 536 _ParkEvent->unpark(); 537 } 538 539 540 bool JavaThread::is_interrupted(bool clear_interrupted) { 541 debug_only(check_for_dangling_thread_pointer(this);) 542 543 if (_threadObj.peek() == NULL) { 544 // If there is no j.l.Thread then it is impossible to have 545 // been interrupted. We can find NULL during VM initialization 546 // or when a JNI thread is still in the process of attaching. 547 // In such cases this must be the current thread. 548 assert(this == Thread::current(), "invariant"); 549 return false; 550 } 551 552 bool interrupted = java_lang_Thread::interrupted(threadObj()); 553 554 // NOTE that since there is no "lock" around the interrupt and 555 // is_interrupted operations, there is the possibility that the 556 // interrupted flag will be "false" but that the 557 // low-level events will be in the signaled state. This is 558 // intentional. The effect of this is that Object.wait() and 559 // LockSupport.park() will appear to have a spurious wakeup, which 560 // is allowed and not harmful, and the possibility is so rare that 561 // it is not worth the added complexity to add yet another lock. 562 // For the sleep event an explicit reset is performed on entry 563 // to JavaThread::sleep, so there is no early return. It has also been 564 // recommended not to put the interrupted flag into the "event" 565 // structure because it hides the issue. 566 // Also, because there is no lock, we must only clear the interrupt 567 // state if we are going to report that we were interrupted; otherwise 568 // an interrupt that happens just after we read the field would be lost. 569 if (interrupted && clear_interrupted) { 570 assert(this == Thread::current(), "only the current thread can clear"); 571 java_lang_Thread::set_interrupted(threadObj(), false); 572 WINDOWS_ONLY(osthread()->set_interrupted(false);) 573 } 574 575 return interrupted; 576 } 577 578 void JavaThread::block_if_vm_exited() { 579 if (_terminated == _vm_exited) { 580 // _vm_exited is set at safepoint, and Threads_lock is never released 581 // so we will block here forever. 582 // Here we can be doing a jump from a safe state to an unsafe state without 583 // proper transition, but it happens after the final safepoint has begun so 584 // this jump won't cause any safepoint problems. 585 set_thread_state(_thread_in_vm); 586 Threads_lock->lock(); 587 ShouldNotReachHere(); 588 } 589 } 590 591 JavaThread::JavaThread(ThreadFunction entry_point, size_t stack_sz) : JavaThread() { 592 _jni_attach_state = _not_attaching_via_jni; 593 set_entry_point(entry_point); 594 // Create the native thread itself. 595 // %note runtime_23 596 os::ThreadType thr_type = os::java_thread; 597 thr_type = entry_point == &CompilerThread::thread_entry ? os::compiler_thread : 598 os::java_thread; 599 os::create_thread(this, thr_type, stack_sz); 600 // The _osthread may be NULL here because we ran out of memory (too many threads active). 601 // We need to throw and OutOfMemoryError - however we cannot do this here because the caller 602 // may hold a lock and all locks must be unlocked before throwing the exception (throwing 603 // the exception consists of creating the exception object & initializing it, initialization 604 // will leave the VM via a JavaCall and then all locks must be unlocked). 605 // 606 // The thread is still suspended when we reach here. Thread must be explicit started 607 // by creator! Furthermore, the thread must also explicitly be added to the Threads list 608 // by calling Threads:add. The reason why this is not done here, is because the thread 609 // object must be fully initialized (take a look at JVM_Start) 610 } 611 612 JavaThread::~JavaThread() { 613 614 // Enqueue OopHandles for release by the service thread. 615 add_oop_handles_for_release(); 616 617 // Return the sleep event to the free list 618 ParkEvent::Release(_SleepEvent); 619 _SleepEvent = NULL; 620 621 // Free any remaining previous UnrollBlock 622 vframeArray* old_array = vframe_array_last(); 623 624 if (old_array != NULL) { 625 Deoptimization::UnrollBlock* old_info = old_array->unroll_block(); 626 old_array->set_unroll_block(NULL); 627 delete old_info; 628 delete old_array; 629 } 630 631 JvmtiDeferredUpdates* updates = deferred_updates(); 632 if (updates != NULL) { 633 // This can only happen if thread is destroyed before deoptimization occurs. 634 assert(updates->count() > 0, "Updates holder not deleted"); 635 // free deferred updates. 636 delete updates; 637 set_deferred_updates(NULL); 638 } 639 640 // All Java related clean up happens in exit 641 ThreadSafepointState::destroy(this); 642 if (_thread_stat != NULL) delete _thread_stat; 643 644 #if INCLUDE_JVMCI 645 if (JVMCICounterSize > 0) { 646 FREE_C_HEAP_ARRAY(jlong, _jvmci_counters); 647 } 648 #endif // INCLUDE_JVMCI 649 } 650 651 652 // First JavaThread specific code executed by a new Java thread. 653 void JavaThread::pre_run() { 654 // empty - see comments in run() 655 } 656 657 // The main routine called by a new Java thread. This isn't overridden 658 // by subclasses, instead different subclasses define a different "entry_point" 659 // which defines the actual logic for that kind of thread. 660 void JavaThread::run() { 661 // initialize thread-local alloc buffer related fields 662 initialize_tlab(); 663 664 _stack_overflow_state.create_stack_guard_pages(); 665 666 cache_global_variables(); 667 668 // Thread is now sufficiently initialized to be handled by the safepoint code as being 669 // in the VM. Change thread state from _thread_new to _thread_in_vm 670 assert(this->thread_state() == _thread_new, "wrong thread state"); 671 set_thread_state(_thread_in_vm); 672 673 // Before a thread is on the threads list it is always safe, so after leaving the 674 // _thread_new we should emit a instruction barrier. The distance to modified code 675 // from here is probably far enough, but this is consistent and safe. 676 OrderAccess::cross_modify_fence(); 677 678 assert(JavaThread::current() == this, "sanity check"); 679 assert(!Thread::current()->owns_locks(), "sanity check"); 680 681 DTRACE_THREAD_PROBE(start, this); 682 683 // This operation might block. We call that after all safepoint checks for a new thread has 684 // been completed. 685 set_active_handles(JNIHandleBlock::allocate_block()); 686 687 if (JvmtiExport::should_post_thread_life()) { 688 JvmtiExport::post_thread_start(this); 689 690 } 691 692 // We call another function to do the rest so we are sure that the stack addresses used 693 // from there will be lower than the stack base just computed. 694 thread_main_inner(); 695 } 696 697 void JavaThread::thread_main_inner() { 698 assert(JavaThread::current() == this, "sanity check"); 699 assert(_threadObj.peek() != NULL, "just checking"); 700 701 // Execute thread entry point unless this thread has a pending exception. 702 // Note: Due to JVMTI StopThread we can have pending exceptions already! 703 if (!this->has_pending_exception()) { 704 { 705 ResourceMark rm(this); 706 this->set_native_thread_name(this->name()); 707 } 708 HandleMark hm(this); 709 this->entry_point()(this, this); 710 } 711 712 DTRACE_THREAD_PROBE(stop, this); 713 714 // Cleanup is handled in post_run() 715 } 716 717 // Shared teardown for all JavaThreads 718 void JavaThread::post_run() { 719 this->exit(false); 720 this->unregister_thread_stack_with_NMT(); 721 // Defer deletion to here to ensure 'this' is still referenceable in call_run 722 // for any shared tear-down. 723 this->smr_delete(); 724 } 725 726 static void ensure_join(JavaThread* thread) { 727 // We do not need to grab the Threads_lock, since we are operating on ourself. 728 Handle threadObj(thread, thread->threadObj()); 729 assert(threadObj.not_null(), "java thread object must exist"); 730 ObjectLocker lock(threadObj, thread); 731 // Thread is exiting. So set thread_status field in java.lang.Thread class to TERMINATED. 732 java_lang_Thread::set_thread_status(threadObj(), JavaThreadStatus::TERMINATED); 733 // Clear the native thread instance - this makes isAlive return false and allows the join() 734 // to complete once we've done the notify_all below 735 java_lang_Thread::set_thread(threadObj(), NULL); 736 lock.notify_all(thread); 737 // Ignore pending exception, since we are exiting anyway 738 thread->clear_pending_exception(); 739 } 740 741 static bool is_daemon(oop threadObj) { 742 return (threadObj != NULL && java_lang_Thread::is_daemon(threadObj)); 743 } 744 745 // For any new cleanup additions, please check to see if they need to be applied to 746 // cleanup_failed_attach_current_thread as well. 747 void JavaThread::exit(bool destroy_vm, ExitType exit_type) { 748 assert(this == JavaThread::current(), "thread consistency check"); 749 assert(!is_exiting(), "should not be exiting or terminated already"); 750 751 elapsedTimer _timer_exit_phase1; 752 elapsedTimer _timer_exit_phase2; 753 elapsedTimer _timer_exit_phase3; 754 elapsedTimer _timer_exit_phase4; 755 756 if (log_is_enabled(Debug, os, thread, timer)) { 757 _timer_exit_phase1.start(); 758 } 759 760 HandleMark hm(this); 761 Handle uncaught_exception(this, this->pending_exception()); 762 this->clear_pending_exception(); 763 Handle threadObj(this, this->threadObj()); 764 assert(threadObj.not_null(), "Java thread object should be created"); 765 766 if (!destroy_vm) { 767 if (uncaught_exception.not_null()) { 768 EXCEPTION_MARK; 769 // Call method Thread.dispatchUncaughtException(). 770 Klass* thread_klass = vmClasses::Thread_klass(); 771 JavaValue result(T_VOID); 772 JavaCalls::call_virtual(&result, 773 threadObj, thread_klass, 774 vmSymbols::dispatchUncaughtException_name(), 775 vmSymbols::throwable_void_signature(), 776 uncaught_exception, 777 THREAD); 778 if (HAS_PENDING_EXCEPTION) { 779 ResourceMark rm(this); 780 jio_fprintf(defaultStream::error_stream(), 781 "\nException: %s thrown from the UncaughtExceptionHandler" 782 " in thread \"%s\"\n", 783 pending_exception()->klass()->external_name(), 784 name()); 785 CLEAR_PENDING_EXCEPTION; 786 } 787 } 788 789 if (!is_Compiler_thread()) { 790 // We have finished executing user-defined Java code and now have to do the 791 // implementation specific clean-up by calling Thread.exit(). We prevent any 792 // asynchronous exceptions from being delivered while in Thread.exit() 793 // to ensure the clean-up is not corrupted. 794 NoAsyncExceptionDeliveryMark _no_async(this); 795 796 EXCEPTION_MARK; 797 JavaValue result(T_VOID); 798 Klass* thread_klass = vmClasses::Thread_klass(); 799 JavaCalls::call_virtual(&result, 800 threadObj, thread_klass, 801 vmSymbols::exit_method_name(), 802 vmSymbols::void_method_signature(), 803 THREAD); 804 CLEAR_PENDING_EXCEPTION; 805 } 806 807 // notify JVMTI 808 if (JvmtiExport::should_post_thread_life()) { 809 JvmtiExport::post_thread_end(this); 810 } 811 } else { 812 // before_exit() has already posted JVMTI THREAD_END events 813 } 814 815 // Cleanup any pending async exception now since we cannot access oops after 816 // BarrierSet::barrier_set()->on_thread_detach() has been executed. 817 if (has_async_exception_condition()) { 818 handshake_state()->clean_async_exception_operation(); 819 } 820 821 // The careful dance between thread suspension and exit is handled here. 822 // Since we are in thread_in_vm state and suspension is done with handshakes, 823 // we can just put in the exiting state and it will be correctly handled. 824 // Also, no more async exceptions will be added to the queue after this point. 825 set_terminated(_thread_exiting); 826 ThreadService::current_thread_exiting(this, is_daemon(threadObj())); 827 828 if (log_is_enabled(Debug, os, thread, timer)) { 829 _timer_exit_phase1.stop(); 830 _timer_exit_phase2.start(); 831 } 832 833 // Capture daemon status before the thread is marked as terminated. 834 bool daemon = is_daemon(threadObj()); 835 836 // Notify waiters on thread object. This has to be done after exit() is called 837 // on the thread (if the thread is the last thread in a daemon ThreadGroup the 838 // group should have the destroyed bit set before waiters are notified). 839 ensure_join(this); 840 assert(!this->has_pending_exception(), "ensure_join should have cleared"); 841 842 if (log_is_enabled(Debug, os, thread, timer)) { 843 _timer_exit_phase2.stop(); 844 _timer_exit_phase3.start(); 845 } 846 // 6282335 JNI DetachCurrentThread spec states that all Java monitors 847 // held by this thread must be released. The spec does not distinguish 848 // between JNI-acquired and regular Java monitors. We can only see 849 // regular Java monitors here if monitor enter-exit matching is broken. 850 // 851 // ensure_join() ignores IllegalThreadStateExceptions, and so does 852 // ObjectSynchronizer::release_monitors_owned_by_thread(). 853 if (exit_type == jni_detach) { 854 // Sanity check even though JNI DetachCurrentThread() would have 855 // returned JNI_ERR if there was a Java frame. JavaThread exit 856 // should be done executing Java code by the time we get here. 857 assert(!this->has_last_Java_frame(), 858 "should not have a Java frame when detaching or exiting"); 859 ObjectSynchronizer::release_monitors_owned_by_thread(this); 860 assert(!this->has_pending_exception(), "release_monitors should have cleared"); 861 } 862 863 // Since above code may not release JNI monitors and if someone forgot to do an 864 // JNI monitorexit, held count should be equal jni count. 865 // Consider scan all object monitor for this owner if JNI count > 0 (at least on detach). 866 assert(this->held_monitor_count() == this->jni_monitor_count(), 867 "held monitor count should be equal to jni: " INT64_FORMAT " != " INT64_FORMAT, 868 (int64_t)this->held_monitor_count(), (int64_t)this->jni_monitor_count()); 869 if (CheckJNICalls && this->jni_monitor_count() > 0) { 870 // We would like a fatal here, but due to we never checked this before there 871 // is a lot of tests which breaks, even with an error log. 872 log_debug(jni)("JavaThread %s (tid: " UINTX_FORMAT ") with Objects still locked by JNI MonitorEnter.", 873 exit_type == JavaThread::normal_exit ? "exiting" : "detaching", os::current_thread_id()); 874 } 875 876 // These things needs to be done while we are still a Java Thread. Make sure that thread 877 // is in a consistent state, in case GC happens 878 JFR_ONLY(Jfr::on_thread_exit(this);) 879 880 if (active_handles() != NULL) { 881 JNIHandleBlock* block = active_handles(); 882 set_active_handles(NULL); 883 JNIHandleBlock::release_block(block); 884 } 885 886 if (free_handle_block() != NULL) { 887 JNIHandleBlock* block = free_handle_block(); 888 set_free_handle_block(NULL); 889 JNIHandleBlock::release_block(block); 890 } 891 892 // These have to be removed while this is still a valid thread. 893 _stack_overflow_state.remove_stack_guard_pages(); 894 895 if (UseTLAB) { 896 tlab().retire(); 897 } 898 899 if (JvmtiEnv::environments_might_exist()) { 900 JvmtiExport::cleanup_thread(this); 901 } 902 903 // We need to cache the thread name for logging purposes below as once 904 // we have called on_thread_detach this thread must not access any oops. 905 char* thread_name = NULL; 906 if (log_is_enabled(Debug, os, thread, timer)) { 907 ResourceMark rm(this); 908 thread_name = os::strdup(name()); 909 } 910 911 log_info(os, thread)("JavaThread %s (tid: " UINTX_FORMAT ").", 912 exit_type == JavaThread::normal_exit ? "exiting" : "detaching", 913 os::current_thread_id()); 914 915 if (log_is_enabled(Debug, os, thread, timer)) { 916 _timer_exit_phase3.stop(); 917 _timer_exit_phase4.start(); 918 } 919 920 #if INCLUDE_JVMCI 921 if (JVMCICounterSize > 0) { 922 if (jvmci_counters_include(this)) { 923 for (int i = 0; i < JVMCICounterSize; i++) { 924 _jvmci_old_thread_counters[i] += _jvmci_counters[i]; 925 } 926 } 927 } 928 #endif // INCLUDE_JVMCI 929 930 // Remove from list of active threads list, and notify VM thread if we are the last non-daemon thread. 931 // We call BarrierSet::barrier_set()->on_thread_detach() here so no touching of oops after this point. 932 Threads::remove(this, daemon); 933 934 if (log_is_enabled(Debug, os, thread, timer)) { 935 _timer_exit_phase4.stop(); 936 log_debug(os, thread, timer)("name='%s'" 937 ", exit-phase1=" JLONG_FORMAT 938 ", exit-phase2=" JLONG_FORMAT 939 ", exit-phase3=" JLONG_FORMAT 940 ", exit-phase4=" JLONG_FORMAT, 941 thread_name, 942 _timer_exit_phase1.milliseconds(), 943 _timer_exit_phase2.milliseconds(), 944 _timer_exit_phase3.milliseconds(), 945 _timer_exit_phase4.milliseconds()); 946 os::free(thread_name); 947 } 948 } 949 950 void JavaThread::cleanup_failed_attach_current_thread(bool is_daemon) { 951 if (active_handles() != NULL) { 952 JNIHandleBlock* block = active_handles(); 953 set_active_handles(NULL); 954 JNIHandleBlock::release_block(block); 955 } 956 957 if (free_handle_block() != NULL) { 958 JNIHandleBlock* block = free_handle_block(); 959 set_free_handle_block(NULL); 960 JNIHandleBlock::release_block(block); 961 } 962 963 // These have to be removed while this is still a valid thread. 964 _stack_overflow_state.remove_stack_guard_pages(); 965 966 if (UseTLAB) { 967 tlab().retire(); 968 } 969 970 Threads::remove(this, is_daemon); 971 this->smr_delete(); 972 } 973 974 JavaThread* JavaThread::active() { 975 Thread* thread = Thread::current(); 976 if (thread->is_Java_thread()) { 977 return JavaThread::cast(thread); 978 } else { 979 assert(thread->is_VM_thread(), "this must be a vm thread"); 980 VM_Operation* op = ((VMThread*) thread)->vm_operation(); 981 JavaThread *ret = op == NULL ? NULL : JavaThread::cast(op->calling_thread()); 982 return ret; 983 } 984 } 985 986 bool JavaThread::is_lock_owned(address adr) const { 987 if (Thread::is_lock_owned(adr)) return true; 988 989 for (MonitorChunk* chunk = monitor_chunks(); chunk != NULL; chunk = chunk->next()) { 990 if (chunk->contains(adr)) return true; 991 } 992 993 return false; 994 } 995 996 oop JavaThread::exception_oop() const { 997 return Atomic::load(&_exception_oop); 998 } 999 1000 void JavaThread::set_exception_oop(oop o) { 1001 Atomic::store(&_exception_oop, o); 1002 } 1003 1004 void JavaThread::add_monitor_chunk(MonitorChunk* chunk) { 1005 chunk->set_next(monitor_chunks()); 1006 set_monitor_chunks(chunk); 1007 } 1008 1009 void JavaThread::remove_monitor_chunk(MonitorChunk* chunk) { 1010 guarantee(monitor_chunks() != NULL, "must be non empty"); 1011 if (monitor_chunks() == chunk) { 1012 set_monitor_chunks(chunk->next()); 1013 } else { 1014 MonitorChunk* prev = monitor_chunks(); 1015 while (prev->next() != chunk) prev = prev->next(); 1016 prev->set_next(chunk->next()); 1017 } 1018 } 1019 1020 void JavaThread::handle_special_runtime_exit_condition() { 1021 if (is_obj_deopt_suspend()) { 1022 frame_anchor()->make_walkable(); 1023 wait_for_object_deoptimization(); 1024 } 1025 JFR_ONLY(SUSPEND_THREAD_CONDITIONAL(this);) 1026 } 1027 1028 1029 // Asynchronous exceptions support 1030 // 1031 void JavaThread::handle_async_exception(oop java_throwable) { 1032 assert(java_throwable != NULL, "should have an _async_exception to throw"); 1033 assert(!is_at_poll_safepoint(), "should have never called this method"); 1034 1035 if (has_last_Java_frame()) { 1036 frame f = last_frame(); 1037 if (f.is_runtime_frame()) { 1038 // If the topmost frame is a runtime stub, then we are calling into 1039 // OptoRuntime from compiled code. Some runtime stubs (new, monitor_exit..) 1040 // must deoptimize the caller before continuing, as the compiled exception 1041 // handler table may not be valid. 1042 RegisterMap reg_map(this, 1043 RegisterMap::UpdateMap::skip, 1044 RegisterMap::ProcessFrames::include, 1045 RegisterMap::WalkContinuation::skip); 1046 frame compiled_frame = f.sender(®_map); 1047 if (!StressCompiledExceptionHandlers && compiled_frame.can_be_deoptimized()) { 1048 Deoptimization::deoptimize(this, compiled_frame); 1049 } 1050 } 1051 } 1052 1053 // We cannot call Exceptions::_throw(...) here because we cannot block 1054 set_pending_exception(java_throwable, __FILE__, __LINE__); 1055 1056 clear_scopedValueBindings(); 1057 1058 LogTarget(Info, exceptions) lt; 1059 if (lt.is_enabled()) { 1060 ResourceMark rm; 1061 LogStream ls(lt); 1062 ls.print("Async. exception installed at runtime exit (" INTPTR_FORMAT ")", p2i(this)); 1063 if (has_last_Java_frame()) { 1064 frame f = last_frame(); 1065 ls.print(" (pc: " INTPTR_FORMAT " sp: " INTPTR_FORMAT " )", p2i(f.pc()), p2i(f.sp())); 1066 } 1067 ls.print_cr(" of type: %s", java_throwable->klass()->external_name()); 1068 } 1069 } 1070 1071 void JavaThread::install_async_exception(AsyncExceptionHandshake* aeh) { 1072 // Do not throw asynchronous exceptions against the compiler thread 1073 // or if the thread is already exiting. 1074 if (!can_call_java() || is_exiting()) { 1075 delete aeh; 1076 return; 1077 } 1078 1079 oop exception = aeh->exception(); 1080 Handshake::execute(aeh, this); // Install asynchronous handshake 1081 1082 ResourceMark rm; 1083 if (log_is_enabled(Info, exceptions)) { 1084 log_info(exceptions)("Pending Async. exception installed of type: %s", 1085 InstanceKlass::cast(exception->klass())->external_name()); 1086 } 1087 // for AbortVMOnException flag 1088 Exceptions::debug_check_abort(exception->klass()->external_name()); 1089 1090 // Interrupt thread so it will wake up from a potential wait()/sleep()/park() 1091 java_lang_Thread::set_interrupted(threadObj(), true); 1092 this->interrupt(); 1093 } 1094 1095 class InstallAsyncExceptionHandshake : public HandshakeClosure { 1096 AsyncExceptionHandshake* _aeh; 1097 public: 1098 InstallAsyncExceptionHandshake(AsyncExceptionHandshake* aeh) : 1099 HandshakeClosure("InstallAsyncException"), _aeh(aeh) {} 1100 ~InstallAsyncExceptionHandshake() { 1101 // If InstallAsyncExceptionHandshake was never executed we need to clean up _aeh. 1102 delete _aeh; 1103 } 1104 void do_thread(Thread* thr) { 1105 JavaThread* target = JavaThread::cast(thr); 1106 target->install_async_exception(_aeh); 1107 _aeh = nullptr; 1108 } 1109 }; 1110 1111 void JavaThread::send_async_exception(JavaThread* target, oop java_throwable) { 1112 OopHandle e(Universe::vm_global(), java_throwable); 1113 InstallAsyncExceptionHandshake iaeh(new AsyncExceptionHandshake(e)); 1114 Handshake::execute(&iaeh, target); 1115 } 1116 1117 #if INCLUDE_JVMTI 1118 void JavaThread::set_is_in_VTMS_transition(bool val) { 1119 _is_in_VTMS_transition = val; 1120 } 1121 1122 #ifdef ASSERT 1123 void JavaThread::set_is_VTMS_transition_disabler(bool val) { 1124 _is_VTMS_transition_disabler = val; 1125 } 1126 #endif 1127 #endif 1128 1129 // External suspension mechanism. 1130 // 1131 // Guarantees on return (for a valid target thread): 1132 // - Target thread will not execute any new bytecode. 1133 // - Target thread will not enter any new monitors. 1134 // 1135 bool JavaThread::java_suspend() { 1136 #if INCLUDE_JVMTI 1137 // Suspending a JavaThread in VTMS transition or disabling VTMS transitions can cause deadlocks. 1138 assert(!is_in_VTMS_transition(), "no suspend allowed in VTMS transition"); 1139 assert(!is_VTMS_transition_disabler(), "no suspend allowed for VTMS transition disablers"); 1140 #endif 1141 1142 guarantee(Thread::is_JavaThread_protected(/* target */ this), 1143 "target JavaThread is not protected in calling context."); 1144 return this->handshake_state()->suspend(); 1145 } 1146 1147 bool JavaThread::java_resume() { 1148 guarantee(Thread::is_JavaThread_protected_by_TLH(/* target */ this), 1149 "missing ThreadsListHandle in calling context."); 1150 return this->handshake_state()->resume(); 1151 } 1152 1153 // Wait for another thread to perform object reallocation and relocking on behalf of 1154 // this thread. The current thread is required to change to _thread_blocked in order 1155 // to be seen to be safepoint/handshake safe whilst suspended and only after becoming 1156 // handshake safe, the other thread can complete the handshake used to synchronize 1157 // with this thread and then perform the reallocation and relocking. 1158 // See EscapeBarrier::sync_and_suspend_*() 1159 1160 void JavaThread::wait_for_object_deoptimization() { 1161 assert(!has_last_Java_frame() || frame_anchor()->walkable(), "should have walkable stack"); 1162 assert(this == Thread::current(), "invariant"); 1163 1164 bool spin_wait = os::is_MP(); 1165 do { 1166 ThreadBlockInVM tbivm(this, true /* allow_suspend */); 1167 // Wait for object deoptimization if requested. 1168 if (spin_wait) { 1169 // A single deoptimization is typically very short. Microbenchmarks 1170 // showed 5% better performance when spinning. 1171 const uint spin_limit = 10 * SpinYield::default_spin_limit; 1172 SpinYield spin(spin_limit); 1173 for (uint i = 0; is_obj_deopt_suspend() && i < spin_limit; i++) { 1174 spin.wait(); 1175 } 1176 // Spin just once 1177 spin_wait = false; 1178 } else { 1179 MonitorLocker ml(this, EscapeBarrier_lock, Monitor::_no_safepoint_check_flag); 1180 if (is_obj_deopt_suspend()) { 1181 ml.wait(); 1182 } 1183 } 1184 // A handshake for obj. deoptimization suspend could have been processed so 1185 // we must check after processing. 1186 } while (is_obj_deopt_suspend()); 1187 } 1188 1189 #ifdef ASSERT 1190 // Verify the JavaThread has not yet been published in the Threads::list, and 1191 // hence doesn't need protection from concurrent access at this stage. 1192 void JavaThread::verify_not_published() { 1193 // Cannot create a ThreadsListHandle here and check !tlh.includes(this) 1194 // since an unpublished JavaThread doesn't participate in the 1195 // Thread-SMR protocol for keeping a ThreadsList alive. 1196 assert(!on_thread_list(), "JavaThread shouldn't have been published yet!"); 1197 } 1198 #endif 1199 1200 // Slow path when the native==>Java barriers detect a safepoint/handshake is 1201 // pending, when _suspend_flags is non-zero or when we need to process a stack 1202 // watermark. Also check for pending async exceptions (except unsafe access error). 1203 // Note only the native==>Java barriers can call this function when thread state 1204 // is _thread_in_native_trans. 1205 void JavaThread::check_special_condition_for_native_trans(JavaThread *thread) { 1206 assert(thread->thread_state() == _thread_in_native_trans, "wrong state"); 1207 assert(!thread->has_last_Java_frame() || thread->frame_anchor()->walkable(), "Unwalkable stack in native->Java transition"); 1208 1209 thread->set_thread_state(_thread_in_vm); 1210 1211 // Enable WXWrite: called directly from interpreter native wrapper. 1212 MACOS_AARCH64_ONLY(ThreadWXEnable wx(WXWrite, thread)); 1213 1214 SafepointMechanism::process_if_requested_with_exit_check(thread, true /* check asyncs */); 1215 1216 // After returning from native, it could be that the stack frames are not 1217 // yet safe to use. We catch such situations in the subsequent stack watermark 1218 // barrier, which will trap unsafe stack frames. 1219 StackWatermarkSet::before_unwind(thread); 1220 } 1221 1222 #ifndef PRODUCT 1223 // Deoptimization 1224 // Function for testing deoptimization 1225 void JavaThread::deoptimize() { 1226 StackFrameStream fst(this, false /* update */, true /* process_frames */); 1227 bool deopt = false; // Dump stack only if a deopt actually happens. 1228 bool only_at = strlen(DeoptimizeOnlyAt) > 0; 1229 // Iterate over all frames in the thread and deoptimize 1230 for (; !fst.is_done(); fst.next()) { 1231 if (fst.current()->can_be_deoptimized()) { 1232 1233 if (only_at) { 1234 // Deoptimize only at particular bcis. DeoptimizeOnlyAt 1235 // consists of comma or carriage return separated numbers so 1236 // search for the current bci in that string. 1237 address pc = fst.current()->pc(); 1238 nmethod* nm = (nmethod*) fst.current()->cb(); 1239 ScopeDesc* sd = nm->scope_desc_at(pc); 1240 char buffer[8]; 1241 jio_snprintf(buffer, sizeof(buffer), "%d", sd->bci()); 1242 size_t len = strlen(buffer); 1243 const char * found = strstr(DeoptimizeOnlyAt, buffer); 1244 while (found != NULL) { 1245 if ((found[len] == ',' || found[len] == '\n' || found[len] == '\0') && 1246 (found == DeoptimizeOnlyAt || found[-1] == ',' || found[-1] == '\n')) { 1247 // Check that the bci found is bracketed by terminators. 1248 break; 1249 } 1250 found = strstr(found + 1, buffer); 1251 } 1252 if (!found) { 1253 continue; 1254 } 1255 } 1256 1257 if (DebugDeoptimization && !deopt) { 1258 deopt = true; // One-time only print before deopt 1259 tty->print_cr("[BEFORE Deoptimization]"); 1260 trace_frames(); 1261 trace_stack(); 1262 } 1263 Deoptimization::deoptimize(this, *fst.current()); 1264 } 1265 } 1266 1267 if (DebugDeoptimization && deopt) { 1268 tty->print_cr("[AFTER Deoptimization]"); 1269 trace_frames(); 1270 } 1271 } 1272 1273 1274 // Make zombies 1275 void JavaThread::make_zombies() { 1276 for (StackFrameStream fst(this, true /* update */, true /* process_frames */); !fst.is_done(); fst.next()) { 1277 if (fst.current()->can_be_deoptimized()) { 1278 // it is a Java nmethod 1279 nmethod* nm = CodeCache::find_nmethod(fst.current()->pc()); 1280 nm->make_not_entrant(); 1281 } 1282 } 1283 } 1284 #endif // PRODUCT 1285 1286 1287 void JavaThread::deoptimize_marked_methods() { 1288 if (!has_last_Java_frame()) return; 1289 StackFrameStream fst(this, false /* update */, true /* process_frames */); 1290 for (; !fst.is_done(); fst.next()) { 1291 if (fst.current()->should_be_deoptimized()) { 1292 Deoptimization::deoptimize(this, *fst.current()); 1293 } 1294 } 1295 } 1296 1297 #ifdef ASSERT 1298 void JavaThread::verify_frame_info() { 1299 assert((!has_last_Java_frame() && java_call_counter() == 0) || 1300 (has_last_Java_frame() && java_call_counter() > 0), 1301 "unexpected frame info: has_last_frame=%s, java_call_counter=%d", 1302 has_last_Java_frame() ? "true" : "false", java_call_counter()); 1303 } 1304 #endif 1305 1306 // Push on a new block of JNI handles. 1307 void JavaThread::push_jni_handle_block() { 1308 // Allocate a new block for JNI handles. 1309 // Inlined code from jni_PushLocalFrame() 1310 JNIHandleBlock* old_handles = active_handles(); 1311 JNIHandleBlock* new_handles = JNIHandleBlock::allocate_block(this); 1312 assert(old_handles != NULL && new_handles != NULL, "should not be NULL"); 1313 new_handles->set_pop_frame_link(old_handles); // make sure java handles get gc'd. 1314 set_active_handles(new_handles); 1315 } 1316 1317 // Pop off the current block of JNI handles. 1318 void JavaThread::pop_jni_handle_block() { 1319 // Release our JNI handle block 1320 JNIHandleBlock* old_handles = active_handles(); 1321 JNIHandleBlock* new_handles = old_handles->pop_frame_link(); 1322 assert(new_handles != nullptr, "should never set active handles to null"); 1323 set_active_handles(new_handles); 1324 old_handles->set_pop_frame_link(NULL); 1325 JNIHandleBlock::release_block(old_handles, this); 1326 } 1327 1328 void JavaThread::oops_do_no_frames(OopClosure* f, CodeBlobClosure* cf) { 1329 // Verify that the deferred card marks have been flushed. 1330 assert(deferred_card_mark().is_empty(), "Should be empty during GC"); 1331 1332 // Traverse the GCHandles 1333 Thread::oops_do_no_frames(f, cf); 1334 1335 if (active_handles() != NULL) { 1336 active_handles()->oops_do(f); 1337 } 1338 1339 DEBUG_ONLY(verify_frame_info();) 1340 1341 if (has_last_Java_frame()) { 1342 // Traverse the monitor chunks 1343 for (MonitorChunk* chunk = monitor_chunks(); chunk != NULL; chunk = chunk->next()) { 1344 chunk->oops_do(f); 1345 } 1346 } 1347 1348 assert(vframe_array_head() == NULL, "deopt in progress at a safepoint!"); 1349 // If we have deferred set_locals there might be oops waiting to be 1350 // written 1351 GrowableArray<jvmtiDeferredLocalVariableSet*>* list = JvmtiDeferredUpdates::deferred_locals(this); 1352 if (list != NULL) { 1353 for (int i = 0; i < list->length(); i++) { 1354 list->at(i)->oops_do(f); 1355 } 1356 } 1357 1358 // Traverse instance variables at the end since the GC may be moving things 1359 // around using this function 1360 f->do_oop((oop*) &_vm_result); 1361 f->do_oop((oop*) &_exception_oop); 1362 #if INCLUDE_JVMCI 1363 f->do_oop((oop*) &_jvmci_reserved_oop0); 1364 #endif 1365 1366 if (jvmti_thread_state() != NULL) { 1367 jvmti_thread_state()->oops_do(f, cf); 1368 } 1369 1370 // The continuation oops are really on the stack. But there is typically at most 1371 // one of those per thread, so we handle them here in the oops_do_no_frames part 1372 // so that we don't have to sprinkle as many stack watermark checks where these 1373 // oops are used. We just need to make sure the thread has started processing. 1374 ContinuationEntry* entry = _cont_entry; 1375 while (entry != nullptr) { 1376 f->do_oop((oop*)entry->cont_addr()); 1377 f->do_oop((oop*)entry->chunk_addr()); 1378 entry = entry->parent(); 1379 } 1380 } 1381 1382 void JavaThread::oops_do_frames(OopClosure* f, CodeBlobClosure* cf) { 1383 if (!has_last_Java_frame()) { 1384 return; 1385 } 1386 // Finish any pending lazy GC activity for the frames 1387 StackWatermarkSet::finish_processing(this, NULL /* context */, StackWatermarkKind::gc); 1388 // Traverse the execution stack 1389 for (StackFrameStream fst(this, true /* update */, false /* process_frames */); !fst.is_done(); fst.next()) { 1390 fst.current()->oops_do(f, cf, fst.register_map()); 1391 } 1392 } 1393 1394 #ifdef ASSERT 1395 void JavaThread::verify_states_for_handshake() { 1396 // This checks that the thread has a correct frame state during a handshake. 1397 verify_frame_info(); 1398 } 1399 #endif 1400 1401 void JavaThread::nmethods_do(CodeBlobClosure* cf) { 1402 DEBUG_ONLY(verify_frame_info();) 1403 MACOS_AARCH64_ONLY(ThreadWXEnable wx(WXWrite, Thread::current());) 1404 1405 if (has_last_Java_frame()) { 1406 // Traverse the execution stack 1407 for (StackFrameStream fst(this, true /* update */, true /* process_frames */); !fst.is_done(); fst.next()) { 1408 fst.current()->nmethods_do(cf); 1409 } 1410 } 1411 1412 if (jvmti_thread_state() != NULL) { 1413 jvmti_thread_state()->nmethods_do(cf); 1414 } 1415 } 1416 1417 void JavaThread::metadata_do(MetadataClosure* f) { 1418 if (has_last_Java_frame()) { 1419 // Traverse the execution stack to call f() on the methods in the stack 1420 for (StackFrameStream fst(this, true /* update */, true /* process_frames */); !fst.is_done(); fst.next()) { 1421 fst.current()->metadata_do(f); 1422 } 1423 } else if (is_Compiler_thread()) { 1424 // need to walk ciMetadata in current compile tasks to keep alive. 1425 CompilerThread* ct = (CompilerThread*)this; 1426 if (ct->env() != NULL) { 1427 ct->env()->metadata_do(f); 1428 } 1429 CompileTask* task = ct->task(); 1430 if (task != NULL) { 1431 task->metadata_do(f); 1432 } 1433 } 1434 } 1435 1436 // Printing 1437 const char* _get_thread_state_name(JavaThreadState _thread_state) { 1438 switch (_thread_state) { 1439 case _thread_uninitialized: return "_thread_uninitialized"; 1440 case _thread_new: return "_thread_new"; 1441 case _thread_new_trans: return "_thread_new_trans"; 1442 case _thread_in_native: return "_thread_in_native"; 1443 case _thread_in_native_trans: return "_thread_in_native_trans"; 1444 case _thread_in_vm: return "_thread_in_vm"; 1445 case _thread_in_vm_trans: return "_thread_in_vm_trans"; 1446 case _thread_in_Java: return "_thread_in_Java"; 1447 case _thread_in_Java_trans: return "_thread_in_Java_trans"; 1448 case _thread_blocked: return "_thread_blocked"; 1449 case _thread_blocked_trans: return "_thread_blocked_trans"; 1450 default: return "unknown thread state"; 1451 } 1452 } 1453 1454 void JavaThread::print_thread_state_on(outputStream *st) const { 1455 st->print_cr(" JavaThread state: %s", _get_thread_state_name(_thread_state)); 1456 } 1457 1458 // Called by Threads::print() for VM_PrintThreads operation 1459 void JavaThread::print_on(outputStream *st, bool print_extended_info) const { 1460 st->print_raw("\""); 1461 st->print_raw(name()); 1462 st->print_raw("\" "); 1463 oop thread_oop = threadObj(); 1464 if (thread_oop != NULL) { 1465 st->print("#" INT64_FORMAT " [%ld] ", (int64_t)java_lang_Thread::thread_id(thread_oop), (long) osthread()->thread_id()); 1466 if (java_lang_Thread::is_daemon(thread_oop)) st->print("daemon "); 1467 st->print("prio=%d ", java_lang_Thread::priority(thread_oop)); 1468 } 1469 Thread::print_on(st, print_extended_info); 1470 // print guess for valid stack memory region (assume 4K pages); helps lock debugging 1471 st->print_cr("[" INTPTR_FORMAT "]", (intptr_t)last_Java_sp() & ~right_n_bits(12)); 1472 if (thread_oop != NULL) { 1473 if (is_vthread_mounted()) { 1474 oop vt = vthread(); 1475 assert(vt != NULL, ""); 1476 st->print_cr(" Carrying virtual thread #" INT64_FORMAT, (int64_t)java_lang_Thread::thread_id(vt)); 1477 } else { 1478 st->print_cr(" java.lang.Thread.State: %s", java_lang_Thread::thread_status_name(thread_oop)); 1479 } 1480 } 1481 #ifndef PRODUCT 1482 _safepoint_state->print_on(st); 1483 #endif // PRODUCT 1484 if (is_Compiler_thread()) { 1485 CompileTask *task = ((CompilerThread*)this)->task(); 1486 if (task != NULL) { 1487 st->print(" Compiling: "); 1488 task->print(st, NULL, true, false); 1489 } else { 1490 st->print(" No compile task"); 1491 } 1492 st->cr(); 1493 } 1494 } 1495 1496 void JavaThread::print() const { print_on(tty); } 1497 1498 void JavaThread::print_name_on_error(outputStream* st, char *buf, int buflen) const { 1499 st->print("%s", get_thread_name_string(buf, buflen)); 1500 } 1501 1502 // Called by fatal error handler. The difference between this and 1503 // JavaThread::print() is that we can't grab lock or allocate memory. 1504 void JavaThread::print_on_error(outputStream* st, char *buf, int buflen) const { 1505 st->print("%s \"%s\"", type_name(), get_thread_name_string(buf, buflen)); 1506 Thread* current = Thread::current_or_null_safe(); 1507 assert(current != nullptr, "cannot be called by a detached thread"); 1508 if (!current->is_Java_thread() || JavaThread::cast(current)->is_oop_safe()) { 1509 // Only access threadObj() if current thread is not a JavaThread 1510 // or if it is a JavaThread that can safely access oops. 1511 oop thread_obj = threadObj(); 1512 if (thread_obj != nullptr) { 1513 if (java_lang_Thread::is_daemon(thread_obj)) st->print(" daemon"); 1514 } 1515 } 1516 st->print(" ["); 1517 st->print("%s", _get_thread_state_name(_thread_state)); 1518 if (osthread()) { 1519 st->print(", id=%d", osthread()->thread_id()); 1520 } 1521 st->print(", stack(" PTR_FORMAT "," PTR_FORMAT ")", 1522 p2i(stack_end()), p2i(stack_base())); 1523 st->print("]"); 1524 1525 ThreadsSMRSupport::print_info_on(this, st); 1526 return; 1527 } 1528 1529 1530 // Verification 1531 1532 void JavaThread::frames_do(void f(frame*, const RegisterMap* map)) { 1533 // ignore if there is no stack 1534 if (!has_last_Java_frame()) return; 1535 // traverse the stack frames. Starts from top frame. 1536 for (StackFrameStream fst(this, true /* update_map */, true /* process_frames */, false /* walk_cont */); !fst.is_done(); fst.next()) { 1537 frame* fr = fst.current(); 1538 f(fr, fst.register_map()); 1539 } 1540 } 1541 1542 static void frame_verify(frame* f, const RegisterMap *map) { f->verify(map); } 1543 1544 void JavaThread::verify() { 1545 // Verify oops in the thread. 1546 oops_do(&VerifyOopClosure::verify_oop, NULL); 1547 1548 // Verify the stack frames. 1549 frames_do(frame_verify); 1550 } 1551 1552 // CR 6300358 (sub-CR 2137150) 1553 // Most callers of this method assume that it can't return NULL but a 1554 // thread may not have a name whilst it is in the process of attaching to 1555 // the VM - see CR 6412693, and there are places where a JavaThread can be 1556 // seen prior to having its threadObj set (e.g., JNI attaching threads and 1557 // if vm exit occurs during initialization). These cases can all be accounted 1558 // for such that this method never returns NULL. 1559 const char* JavaThread::name() const { 1560 if (Thread::is_JavaThread_protected(/* target */ this)) { 1561 // The target JavaThread is protected so get_thread_name_string() is safe: 1562 return get_thread_name_string(); 1563 } 1564 1565 // The target JavaThread is not protected so we return the default: 1566 return Thread::name(); 1567 } 1568 1569 // Returns a non-NULL representation of this thread's name, or a suitable 1570 // descriptive string if there is no set name. 1571 const char* JavaThread::get_thread_name_string(char* buf, int buflen) const { 1572 const char* name_str; 1573 #ifdef ASSERT 1574 Thread* current = Thread::current_or_null_safe(); 1575 assert(current != nullptr, "cannot be called by a detached thread"); 1576 if (!current->is_Java_thread() || JavaThread::cast(current)->is_oop_safe()) { 1577 // Only access threadObj() if current thread is not a JavaThread 1578 // or if it is a JavaThread that can safely access oops. 1579 #endif 1580 oop thread_obj = threadObj(); 1581 if (thread_obj != NULL) { 1582 oop name = java_lang_Thread::name(thread_obj); 1583 if (name != NULL) { 1584 if (buf == NULL) { 1585 name_str = java_lang_String::as_utf8_string(name); 1586 } else { 1587 name_str = java_lang_String::as_utf8_string(name, buf, buflen); 1588 } 1589 } else if (is_attaching_via_jni()) { // workaround for 6412693 - see 6404306 1590 name_str = "<no-name - thread is attaching>"; 1591 } else { 1592 name_str = "<un-named>"; 1593 } 1594 } else { 1595 name_str = Thread::name(); 1596 } 1597 #ifdef ASSERT 1598 } else { 1599 // Current JavaThread has exited... 1600 if (current == this) { 1601 // ... and is asking about itself: 1602 name_str = "<no-name - current JavaThread has exited>"; 1603 } else { 1604 // ... and it can't safely determine this JavaThread's name so 1605 // use the default thread name. 1606 name_str = Thread::name(); 1607 } 1608 } 1609 #endif 1610 assert(name_str != NULL, "unexpected NULL thread name"); 1611 return name_str; 1612 } 1613 1614 // Helper to extract the name from the thread oop for logging. 1615 const char* JavaThread::name_for(oop thread_obj) { 1616 assert(thread_obj != NULL, "precondition"); 1617 oop name = java_lang_Thread::name(thread_obj); 1618 const char* name_str; 1619 if (name != NULL) { 1620 name_str = java_lang_String::as_utf8_string(name); 1621 } else { 1622 name_str = "<un-named>"; 1623 } 1624 return name_str; 1625 } 1626 1627 void JavaThread::prepare(jobject jni_thread, ThreadPriority prio) { 1628 1629 assert(Threads_lock->owner() == Thread::current(), "must have threads lock"); 1630 assert(NoPriority <= prio && prio <= MaxPriority, "sanity check"); 1631 // Link Java Thread object <-> C++ Thread 1632 1633 // Get the C++ thread object (an oop) from the JNI handle (a jthread) 1634 // and put it into a new Handle. The Handle "thread_oop" can then 1635 // be used to pass the C++ thread object to other methods. 1636 1637 // Set the Java level thread object (jthread) field of the 1638 // new thread (a JavaThread *) to C++ thread object using the 1639 // "thread_oop" handle. 1640 1641 // Set the thread field (a JavaThread *) of the 1642 // oop representing the java_lang_Thread to the new thread (a JavaThread *). 1643 1644 Handle thread_oop(Thread::current(), 1645 JNIHandles::resolve_non_null(jni_thread)); 1646 assert(InstanceKlass::cast(thread_oop->klass())->is_linked(), 1647 "must be initialized"); 1648 set_threadOopHandles(thread_oop()); 1649 java_lang_Thread::set_thread(thread_oop(), this); 1650 1651 if (prio == NoPriority) { 1652 prio = java_lang_Thread::priority(thread_oop()); 1653 assert(prio != NoPriority, "A valid priority should be present"); 1654 } 1655 1656 // Push the Java priority down to the native thread; needs Threads_lock 1657 Thread::set_priority(this, prio); 1658 1659 // Add the new thread to the Threads list and set it in motion. 1660 // We must have threads lock in order to call Threads::add. 1661 // It is crucial that we do not block before the thread is 1662 // added to the Threads list for if a GC happens, then the java_thread oop 1663 // will not be visited by GC. 1664 Threads::add(this); 1665 } 1666 1667 oop JavaThread::current_park_blocker() { 1668 // Support for JSR-166 locks 1669 oop thread_oop = threadObj(); 1670 if (thread_oop != NULL) { 1671 return java_lang_Thread::park_blocker(thread_oop); 1672 } 1673 return NULL; 1674 } 1675 1676 1677 void JavaThread::print_stack_on(outputStream* st) { 1678 if (!has_last_Java_frame()) return; 1679 1680 Thread* current_thread = Thread::current(); 1681 ResourceMark rm(current_thread); 1682 HandleMark hm(current_thread); 1683 1684 RegisterMap reg_map(this, 1685 RegisterMap::UpdateMap::include, 1686 RegisterMap::ProcessFrames::include, 1687 RegisterMap::WalkContinuation::skip); 1688 vframe* start_vf = platform_thread_last_java_vframe(®_map); 1689 int count = 0; 1690 for (vframe* f = start_vf; f != NULL; f = f->sender()) { 1691 if (f->is_java_frame()) { 1692 javaVFrame* jvf = javaVFrame::cast(f); 1693 java_lang_Throwable::print_stack_element(st, jvf->method(), jvf->bci()); 1694 1695 // Print out lock information 1696 if (JavaMonitorsInStackTrace) { 1697 jvf->print_lock_info_on(st, count); 1698 } 1699 } else { 1700 // Ignore non-Java frames 1701 } 1702 1703 // Bail-out case for too deep stacks if MaxJavaStackTraceDepth > 0 1704 count++; 1705 if (MaxJavaStackTraceDepth > 0 && MaxJavaStackTraceDepth == count) return; 1706 } 1707 } 1708 1709 #if INCLUDE_JVMTI 1710 // Rebind JVMTI thread state from carrier to virtual or from virtual to carrier. 1711 JvmtiThreadState* JavaThread::rebind_to_jvmti_thread_state_of(oop thread_oop) { 1712 set_jvmti_vthread(thread_oop); 1713 1714 // unbind current JvmtiThreadState from JavaThread 1715 JvmtiThreadState::unbind_from(jvmti_thread_state(), this); 1716 1717 // bind new JvmtiThreadState to JavaThread 1718 JvmtiThreadState::bind_to(java_lang_Thread::jvmti_thread_state(thread_oop), this); 1719 1720 return jvmti_thread_state(); 1721 } 1722 #endif 1723 1724 // JVMTI PopFrame support 1725 void JavaThread::popframe_preserve_args(ByteSize size_in_bytes, void* start) { 1726 assert(_popframe_preserved_args == NULL, "should not wipe out old PopFrame preserved arguments"); 1727 if (in_bytes(size_in_bytes) != 0) { 1728 _popframe_preserved_args = NEW_C_HEAP_ARRAY(char, in_bytes(size_in_bytes), mtThread); 1729 _popframe_preserved_args_size = in_bytes(size_in_bytes); 1730 Copy::conjoint_jbytes(start, _popframe_preserved_args, _popframe_preserved_args_size); 1731 } 1732 } 1733 1734 void* JavaThread::popframe_preserved_args() { 1735 return _popframe_preserved_args; 1736 } 1737 1738 ByteSize JavaThread::popframe_preserved_args_size() { 1739 return in_ByteSize(_popframe_preserved_args_size); 1740 } 1741 1742 WordSize JavaThread::popframe_preserved_args_size_in_words() { 1743 int sz = in_bytes(popframe_preserved_args_size()); 1744 assert(sz % wordSize == 0, "argument size must be multiple of wordSize"); 1745 return in_WordSize(sz / wordSize); 1746 } 1747 1748 void JavaThread::popframe_free_preserved_args() { 1749 assert(_popframe_preserved_args != NULL, "should not free PopFrame preserved arguments twice"); 1750 FREE_C_HEAP_ARRAY(char, (char*)_popframe_preserved_args); 1751 _popframe_preserved_args = NULL; 1752 _popframe_preserved_args_size = 0; 1753 } 1754 1755 #ifndef PRODUCT 1756 1757 void JavaThread::trace_frames() { 1758 tty->print_cr("[Describe stack]"); 1759 int frame_no = 1; 1760 for (StackFrameStream fst(this, true /* update */, true /* process_frames */); !fst.is_done(); fst.next()) { 1761 tty->print(" %d. ", frame_no++); 1762 fst.current()->print_value_on(tty, this); 1763 tty->cr(); 1764 } 1765 } 1766 1767 class PrintAndVerifyOopClosure: public OopClosure { 1768 protected: 1769 template <class T> inline void do_oop_work(T* p) { 1770 oop obj = RawAccess<>::oop_load(p); 1771 if (obj == NULL) return; 1772 tty->print(INTPTR_FORMAT ": ", p2i(p)); 1773 if (oopDesc::is_oop_or_null(obj)) { 1774 if (obj->is_objArray()) { 1775 tty->print_cr("valid objArray: " INTPTR_FORMAT, p2i(obj)); 1776 } else { 1777 obj->print(); 1778 } 1779 } else { 1780 tty->print_cr("invalid oop: " INTPTR_FORMAT, p2i(obj)); 1781 } 1782 tty->cr(); 1783 } 1784 public: 1785 virtual void do_oop(oop* p) { do_oop_work(p); } 1786 virtual void do_oop(narrowOop* p) { do_oop_work(p); } 1787 }; 1788 1789 #ifdef ASSERT 1790 // Print or validate the layout of stack frames 1791 void JavaThread::print_frame_layout(int depth, bool validate_only) { 1792 ResourceMark rm; 1793 PreserveExceptionMark pm(this); 1794 FrameValues values; 1795 int frame_no = 0; 1796 for (StackFrameStream fst(this, true, true, true); !fst.is_done(); fst.next()) { 1797 fst.current()->describe(values, ++frame_no, fst.register_map()); 1798 if (depth == frame_no) break; 1799 } 1800 Continuation::describe(values); 1801 if (validate_only) { 1802 values.validate(); 1803 } else { 1804 tty->print_cr("[Describe stack layout]"); 1805 values.print(this); 1806 } 1807 } 1808 #endif 1809 1810 void JavaThread::trace_stack_from(vframe* start_vf) { 1811 ResourceMark rm; 1812 int vframe_no = 1; 1813 for (vframe* f = start_vf; f; f = f->sender()) { 1814 if (f->is_java_frame()) { 1815 javaVFrame::cast(f)->print_activation(vframe_no++); 1816 } else { 1817 f->print(); 1818 } 1819 if (vframe_no > StackPrintLimit) { 1820 tty->print_cr("...<more frames>..."); 1821 return; 1822 } 1823 } 1824 } 1825 1826 1827 void JavaThread::trace_stack() { 1828 if (!has_last_Java_frame()) return; 1829 Thread* current_thread = Thread::current(); 1830 ResourceMark rm(current_thread); 1831 HandleMark hm(current_thread); 1832 RegisterMap reg_map(this, 1833 RegisterMap::UpdateMap::include, 1834 RegisterMap::ProcessFrames::include, 1835 RegisterMap::WalkContinuation::skip); 1836 trace_stack_from(last_java_vframe(®_map)); 1837 } 1838 1839 1840 #endif // PRODUCT 1841 1842 void JavaThread::inc_held_monitor_count(int i, bool jni) { 1843 #ifdef SUPPORT_MONITOR_COUNT 1844 assert(_held_monitor_count >= 0, "Must always be greater than 0: " INT64_FORMAT, (int64_t)_held_monitor_count); 1845 _held_monitor_count += i; 1846 if (jni) { 1847 assert(_jni_monitor_count >= 0, "Must always be greater than 0: " INT64_FORMAT, (int64_t)_jni_monitor_count); 1848 _jni_monitor_count += i; 1849 } 1850 #endif 1851 } 1852 1853 void JavaThread::dec_held_monitor_count(int i, bool jni) { 1854 #ifdef SUPPORT_MONITOR_COUNT 1855 _held_monitor_count -= i; 1856 assert(_held_monitor_count >= 0, "Must always be greater than 0: " INT64_FORMAT, (int64_t)_held_monitor_count); 1857 if (jni) { 1858 _jni_monitor_count -= i; 1859 assert(_jni_monitor_count >= 0, "Must always be greater than 0: " INT64_FORMAT, (int64_t)_jni_monitor_count); 1860 } 1861 #endif 1862 } 1863 1864 frame JavaThread::vthread_last_frame() { 1865 assert (is_vthread_mounted(), "Virtual thread not mounted"); 1866 return last_frame(); 1867 } 1868 1869 frame JavaThread::carrier_last_frame(RegisterMap* reg_map) { 1870 const ContinuationEntry* entry = vthread_continuation(); 1871 guarantee (entry != NULL, "Not a carrier thread"); 1872 frame f = entry->to_frame(); 1873 if (reg_map->process_frames()) { 1874 entry->flush_stack_processing(this); 1875 } 1876 entry->update_register_map(reg_map); 1877 return f.sender(reg_map); 1878 } 1879 1880 frame JavaThread::platform_thread_last_frame(RegisterMap* reg_map) { 1881 return is_vthread_mounted() ? carrier_last_frame(reg_map) : last_frame(); 1882 } 1883 1884 javaVFrame* JavaThread::last_java_vframe(const frame f, RegisterMap *reg_map) { 1885 assert(reg_map != NULL, "a map must be given"); 1886 for (vframe* vf = vframe::new_vframe(&f, reg_map, this); vf; vf = vf->sender()) { 1887 if (vf->is_java_frame()) return javaVFrame::cast(vf); 1888 } 1889 return NULL; 1890 } 1891 1892 Klass* JavaThread::security_get_caller_class(int depth) { 1893 ResetNoHandleMark rnhm; 1894 HandleMark hm(Thread::current()); 1895 1896 vframeStream vfst(this); 1897 vfst.security_get_caller_frame(depth); 1898 if (!vfst.at_end()) { 1899 return vfst.method()->method_holder(); 1900 } 1901 return NULL; 1902 } 1903 1904 // java.lang.Thread.sleep support 1905 // Returns true if sleep time elapsed as expected, and false 1906 // if the thread was interrupted. 1907 bool JavaThread::sleep(jlong millis) { 1908 assert(this == Thread::current(), "thread consistency check"); 1909 1910 ParkEvent * const slp = this->_SleepEvent; 1911 // Because there can be races with thread interruption sending an unpark() 1912 // to the event, we explicitly reset it here to avoid an immediate return. 1913 // The actual interrupt state will be checked before we park(). 1914 slp->reset(); 1915 // Thread interruption establishes a happens-before ordering in the 1916 // Java Memory Model, so we need to ensure we synchronize with the 1917 // interrupt state. 1918 OrderAccess::fence(); 1919 1920 jlong prevtime = os::javaTimeNanos(); 1921 1922 for (;;) { 1923 // interruption has precedence over timing out 1924 if (this->is_interrupted(true)) { 1925 return false; 1926 } 1927 1928 if (millis <= 0) { 1929 return true; 1930 } 1931 1932 { 1933 ThreadBlockInVM tbivm(this); 1934 OSThreadWaitState osts(this->osthread(), false /* not Object.wait() */); 1935 slp->park(millis); 1936 } 1937 1938 // Update elapsed time tracking 1939 jlong newtime = os::javaTimeNanos(); 1940 if (newtime - prevtime < 0) { 1941 // time moving backwards, should only happen if no monotonic clock 1942 // not a guarantee() because JVM should not abort on kernel/glibc bugs 1943 assert(false, 1944 "unexpected time moving backwards detected in JavaThread::sleep()"); 1945 } else { 1946 millis -= (newtime - prevtime) / NANOSECS_PER_MILLISEC; 1947 } 1948 prevtime = newtime; 1949 } 1950 } 1951 1952 // Last thread running calls java.lang.Shutdown.shutdown() 1953 void JavaThread::invoke_shutdown_hooks() { 1954 HandleMark hm(this); 1955 1956 // We could get here with a pending exception, if so clear it now or 1957 // it will cause MetaspaceShared::link_shared_classes to 1958 // fail for dynamic dump. 1959 if (this->has_pending_exception()) { 1960 this->clear_pending_exception(); 1961 } 1962 1963 #if INCLUDE_CDS 1964 // Link all classes for dynamic CDS dumping before vm exit. 1965 // Same operation is being done in JVM_BeforeHalt for handling the 1966 // case where the application calls System.exit(). 1967 if (DynamicArchive::should_dump_at_vm_exit()) { 1968 DynamicArchive::prepare_for_dump_at_exit(); 1969 } 1970 #endif 1971 1972 EXCEPTION_MARK; 1973 Klass* shutdown_klass = 1974 SystemDictionary::resolve_or_null(vmSymbols::java_lang_Shutdown(), 1975 THREAD); 1976 if (shutdown_klass != NULL) { 1977 // SystemDictionary::resolve_or_null will return null if there was 1978 // an exception. If we cannot load the Shutdown class, just don't 1979 // call Shutdown.shutdown() at all. This will mean the shutdown hooks 1980 // won't be run. Note that if a shutdown hook was registered, 1981 // the Shutdown class would have already been loaded 1982 // (Runtime.addShutdownHook will load it). 1983 JavaValue result(T_VOID); 1984 JavaCalls::call_static(&result, 1985 shutdown_klass, 1986 vmSymbols::shutdown_name(), 1987 vmSymbols::void_method_signature(), 1988 THREAD); 1989 } 1990 CLEAR_PENDING_EXCEPTION; 1991 } 1992 1993 #ifndef PRODUCT 1994 void JavaThread::verify_cross_modify_fence_failure(JavaThread *thread) { 1995 report_vm_error(__FILE__, __LINE__, "Cross modify fence failure", "%p", thread); 1996 } 1997 #endif 1998 1999 // Helper function to create the java.lang.Thread object for a 2000 // VM-internal thread. The thread will have the given name, and be 2001 // a member of the "system" ThreadGroup. 2002 Handle JavaThread::create_system_thread_object(const char* name, 2003 bool is_visible, TRAPS) { 2004 Handle string = java_lang_String::create_from_str(name, CHECK_NH); 2005 2006 // Initialize thread_oop to put it into the system threadGroup. 2007 // This is done by calling the Thread(ThreadGroup group, String name) constructor. 2008 Handle thread_group(THREAD, Universe::system_thread_group()); 2009 Handle thread_oop = 2010 JavaCalls::construct_new_instance(vmClasses::Thread_klass(), 2011 vmSymbols::threadgroup_string_void_signature(), 2012 thread_group, 2013 string, 2014 CHECK_NH); 2015 2016 return thread_oop; 2017 } 2018 2019 // Starts the target JavaThread as a daemon of the given priority, and 2020 // bound to the given java.lang.Thread instance. 2021 // The Threads_lock is held for the duration. 2022 void JavaThread::start_internal_daemon(JavaThread* current, JavaThread* target, 2023 Handle thread_oop, ThreadPriority prio) { 2024 2025 assert(target->osthread() != NULL, "target thread is not properly initialized"); 2026 2027 MutexLocker mu(current, Threads_lock); 2028 2029 // Initialize the fields of the thread_oop first. 2030 2031 java_lang_Thread::set_thread(thread_oop(), target); // isAlive == true now 2032 2033 if (prio != NoPriority) { 2034 java_lang_Thread::set_priority(thread_oop(), prio); 2035 // Note: we don't call os::set_priority here. Possibly we should, 2036 // else all threads should call it themselves when they first run. 2037 } 2038 2039 java_lang_Thread::set_daemon(thread_oop()); 2040 2041 // Now bind the thread_oop to the target JavaThread. 2042 target->set_threadOopHandles(thread_oop()); 2043 2044 Threads::add(target); // target is now visible for safepoint/handshake 2045 Thread::start(target); 2046 } 2047 2048 void JavaThread::vm_exit_on_osthread_failure(JavaThread* thread) { 2049 // At this point it may be possible that no osthread was created for the 2050 // JavaThread due to lack of resources. However, since this must work 2051 // for critical system threads just check and abort if this fails. 2052 if (thread->osthread() == nullptr) { 2053 // This isn't really an OOM condition, but historically this is what 2054 // we report. 2055 vm_exit_during_initialization("java.lang.OutOfMemoryError", 2056 os::native_thread_creation_failed_msg()); 2057 } 2058 } 2059 2060 // Deferred OopHandle release support. 2061 2062 class OopHandleList : public CHeapObj<mtInternal> { 2063 static const int _count = 4; 2064 OopHandle _handles[_count]; 2065 OopHandleList* _next; 2066 int _index; 2067 public: 2068 OopHandleList(OopHandleList* next) : _next(next), _index(0) {} 2069 void add(OopHandle h) { 2070 assert(_index < _count, "too many additions"); 2071 _handles[_index++] = h; 2072 } 2073 ~OopHandleList() { 2074 assert(_index == _count, "usage error"); 2075 for (int i = 0; i < _index; i++) { 2076 _handles[i].release(JavaThread::thread_oop_storage()); 2077 } 2078 } 2079 OopHandleList* next() const { return _next; } 2080 }; 2081 2082 OopHandleList* JavaThread::_oop_handle_list = nullptr; 2083 2084 // Called by the ServiceThread to do the work of releasing 2085 // the OopHandles. 2086 void JavaThread::release_oop_handles() { 2087 OopHandleList* list; 2088 { 2089 MutexLocker ml(Service_lock, Mutex::_no_safepoint_check_flag); 2090 list = _oop_handle_list; 2091 _oop_handle_list = nullptr; 2092 } 2093 assert(!SafepointSynchronize::is_at_safepoint(), "cannot be called at a safepoint"); 2094 2095 while (list != nullptr) { 2096 OopHandleList* l = list; 2097 list = l->next(); 2098 delete l; 2099 } 2100 } 2101 2102 // Add our OopHandles for later release. 2103 void JavaThread::add_oop_handles_for_release() { 2104 MutexLocker ml(Service_lock, Mutex::_no_safepoint_check_flag); 2105 OopHandleList* new_head = new OopHandleList(_oop_handle_list); 2106 new_head->add(_threadObj); 2107 new_head->add(_vthread); 2108 new_head->add(_jvmti_vthread); 2109 new_head->add(_scopedValueCache); 2110 _oop_handle_list = new_head; 2111 Service_lock->notify_all(); 2112 }