1 /* 2 * Copyright (c) 1997, 2023, Oracle and/or its affiliates. All rights reserved. 3 * Copyright (c) 2021, Azul Systems, Inc. All rights reserved. 4 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 5 * 6 * This code is free software; you can redistribute it and/or modify it 7 * under the terms of the GNU General Public License version 2 only, as 8 * published by the Free Software Foundation. 9 * 10 * This code is distributed in the hope that it will be useful, but WITHOUT 11 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 12 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 13 * version 2 for more details (a copy is included in the LICENSE file that 14 * accompanied this code). 15 * 16 * You should have received a copy of the GNU General Public License version 17 * 2 along with this work; if not, write to the Free Software Foundation, 18 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 19 * 20 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 21 * or visit www.oracle.com if you need additional information or have any 22 * questions. 23 * 24 */ 25 26 #ifndef SHARE_RUNTIME_JAVATHREAD_HPP 27 #define SHARE_RUNTIME_JAVATHREAD_HPP 28 29 #include "jni.h" 30 #include "memory/allocation.hpp" 31 #include "oops/oop.hpp" 32 #include "oops/oopHandle.hpp" 33 #include "runtime/frame.hpp" 34 #include "runtime/globals.hpp" 35 #include "runtime/handshake.hpp" 36 #include "runtime/javaFrameAnchor.hpp" 37 #include "runtime/lockStack.hpp" 38 #include "runtime/park.hpp" 39 #include "runtime/safepointMechanism.hpp" 40 #include "runtime/stackWatermarkSet.hpp" 41 #include "runtime/stackOverflow.hpp" 42 #include "runtime/thread.hpp" 43 #include "runtime/threadHeapSampler.hpp" 44 #include "runtime/threadStatisticalInfo.hpp" 45 #include "utilities/exceptions.hpp" 46 #include "utilities/globalDefinitions.hpp" 47 #include "utilities/macros.hpp" 48 #if INCLUDE_JFR 49 #include "jfr/support/jfrThreadExtension.hpp" 50 #endif 51 52 class AsyncExceptionHandshake; 53 class ContinuationEntry; 54 class DeoptResourceMark; 55 class JNIHandleBlock; 56 class JVMCIRuntime; 57 58 class JvmtiDeferredUpdates; 59 class JvmtiSampledObjectAllocEventCollector; 60 class JvmtiThreadState; 61 62 class Metadata; 63 class OopHandleList; 64 class OopStorage; 65 class OSThread; 66 67 class ThreadsList; 68 class ThreadSafepointState; 69 class ThreadStatistics; 70 71 class vframeArray; 72 class vframe; 73 class javaVFrame; 74 75 class JavaThread; 76 typedef void (*ThreadFunction)(JavaThread*, TRAPS); 77 78 class JavaThread: public Thread { 79 friend class VMStructs; 80 friend class JVMCIVMStructs; 81 friend class WhiteBox; 82 friend class ThreadsSMRSupport; // to access _threadObj for exiting_threads_oops_do 83 friend class HandshakeState; 84 friend class Continuation; 85 friend class Threads; 86 friend class ServiceThread; // for deferred OopHandle release access 87 private: 88 bool _on_thread_list; // Is set when this JavaThread is added to the Threads list 89 90 // All references to Java objects managed via OopHandles. These 91 // have to be released by the ServiceThread after the JavaThread has 92 // terminated - see add_oop_handles_for_release(). 93 OopHandle _threadObj; // The Java level thread object 94 OopHandle _vthread; // the value returned by Thread.currentThread(): the virtual thread, if mounted, otherwise _threadObj 95 OopHandle _jvmti_vthread; 96 OopHandle _scopedValueCache; 97 98 static OopStorage* _thread_oop_storage; 99 100 #ifdef ASSERT 101 private: 102 int _java_call_counter; 103 104 public: 105 int java_call_counter() { return _java_call_counter; } 106 void inc_java_call_counter() { _java_call_counter++; } 107 void dec_java_call_counter() { 108 assert(_java_call_counter > 0, "Invalid nesting of JavaCallWrapper"); 109 _java_call_counter--; 110 } 111 private: // restore original namespace restriction 112 #endif // ifdef ASSERT 113 114 JavaFrameAnchor _anchor; // Encapsulation of current java frame and it state 115 116 ThreadFunction _entry_point; 117 118 JNIEnv _jni_environment; 119 120 // Deopt support 121 DeoptResourceMark* _deopt_mark; // Holds special ResourceMark for deoptimization 122 123 CompiledMethod* _deopt_nmethod; // CompiledMethod that is currently being deoptimized 124 vframeArray* _vframe_array_head; // Holds the heap of the active vframeArrays 125 vframeArray* _vframe_array_last; // Holds last vFrameArray we popped 126 // Holds updates by JVMTI agents for compiled frames that cannot be performed immediately. They 127 // will be carried out as soon as possible which, in most cases, is just before deoptimization of 128 // the frame, when control returns to it. 129 JvmtiDeferredUpdates* _jvmti_deferred_updates; 130 131 // Handshake value for fixing 6243940. We need a place for the i2c 132 // adapter to store the callee Method*. This value is NEVER live 133 // across a gc point so it does NOT have to be gc'd 134 // The handshake is open ended since we can't be certain that it will 135 // be nulled. This is because we rarely ever see the race and end up 136 // in handle_wrong_method which is the backend of the handshake. See 137 // code in i2c adapters and handle_wrong_method. 138 139 Method* _callee_target; 140 141 // Used to pass back results to the interpreter or generated code running Java code. 142 oop _vm_result; // oop result is GC-preserved 143 Metadata* _vm_result_2; // non-oop result 144 145 // See ReduceInitialCardMarks: this holds the precise space interval of 146 // the most recent slow path allocation for which compiled code has 147 // elided card-marks for performance along the fast-path. 148 MemRegion _deferred_card_mark; 149 150 ObjectMonitor* volatile _current_pending_monitor; // ObjectMonitor this thread is waiting to lock 151 bool _current_pending_monitor_is_from_java; // locking is from Java code 152 ObjectMonitor* volatile _current_waiting_monitor; // ObjectMonitor on which this thread called Object.wait() 153 154 // Active_handles points to a block of handles 155 JNIHandleBlock* _active_handles; 156 157 // One-element thread local free list 158 JNIHandleBlock* _free_handle_block; 159 160 public: 161 volatile intptr_t _Stalled; 162 163 // For tracking the heavyweight monitor the thread is pending on. 164 ObjectMonitor* current_pending_monitor() { 165 // Use Atomic::load() to prevent data race between concurrent modification and 166 // concurrent readers, e.g. ThreadService::get_current_contended_monitor(). 167 // Especially, reloading pointer from thread after null check must be prevented. 168 return Atomic::load(&_current_pending_monitor); 169 } 170 void set_current_pending_monitor(ObjectMonitor* monitor) { 171 Atomic::store(&_current_pending_monitor, monitor); 172 } 173 void set_current_pending_monitor_is_from_java(bool from_java) { 174 _current_pending_monitor_is_from_java = from_java; 175 } 176 bool current_pending_monitor_is_from_java() { 177 return _current_pending_monitor_is_from_java; 178 } 179 ObjectMonitor* current_waiting_monitor() { 180 // See the comment in current_pending_monitor() above. 181 return Atomic::load(&_current_waiting_monitor); 182 } 183 void set_current_waiting_monitor(ObjectMonitor* monitor) { 184 Atomic::store(&_current_waiting_monitor, monitor); 185 } 186 187 // JNI handle support 188 JNIHandleBlock* active_handles() const { return _active_handles; } 189 void set_active_handles(JNIHandleBlock* block) { _active_handles = block; } 190 JNIHandleBlock* free_handle_block() const { return _free_handle_block; } 191 void set_free_handle_block(JNIHandleBlock* block) { _free_handle_block = block; } 192 193 void push_jni_handle_block(); 194 void pop_jni_handle_block(); 195 196 private: 197 MonitorChunk* _monitor_chunks; // Contains the off stack monitors 198 // allocated during deoptimization 199 // and by JNI_MonitorEnter/Exit 200 201 enum SuspendFlags { 202 // NOTE: avoid using the sign-bit as cc generates different test code 203 // when the sign-bit is used, and sometimes incorrectly - see CR 6398077 204 _trace_flag = 0x00000004U, // call tracing backend 205 _obj_deopt = 0x00000008U // suspend for object reallocation and relocking for JVMTI agent 206 }; 207 208 // various suspension related flags - atomically updated 209 volatile uint32_t _suspend_flags; 210 211 inline void set_suspend_flag(SuspendFlags f); 212 inline void clear_suspend_flag(SuspendFlags f); 213 214 public: 215 inline void set_trace_flag(); 216 inline void clear_trace_flag(); 217 inline void set_obj_deopt_flag(); 218 inline void clear_obj_deopt_flag(); 219 bool is_trace_suspend() { return (_suspend_flags & _trace_flag) != 0; } 220 bool is_obj_deopt_suspend() { return (_suspend_flags & _obj_deopt) != 0; } 221 222 // Asynchronous exception support 223 private: 224 friend class InstallAsyncExceptionHandshake; 225 friend class AsyncExceptionHandshake; 226 friend class HandshakeState; 227 228 void install_async_exception(AsyncExceptionHandshake* aec = nullptr); 229 void handle_async_exception(oop java_throwable); 230 public: 231 bool has_async_exception_condition(); 232 inline void set_pending_unsafe_access_error(); 233 static void send_async_exception(JavaThread* jt, oop java_throwable); 234 235 class NoAsyncExceptionDeliveryMark : public StackObj { 236 friend JavaThread; 237 JavaThread *_target; 238 inline NoAsyncExceptionDeliveryMark(JavaThread *t); 239 inline ~NoAsyncExceptionDeliveryMark(); 240 }; 241 242 // Safepoint support 243 public: // Expose _thread_state for SafeFetchInt() 244 volatile JavaThreadState _thread_state; 245 private: 246 SafepointMechanism::ThreadData _poll_data; 247 ThreadSafepointState* _safepoint_state; // Holds information about a thread during a safepoint 248 address _saved_exception_pc; // Saved pc of instruction where last implicit exception happened 249 NOT_PRODUCT(bool _requires_cross_modify_fence;) // State used by VerifyCrossModifyFence 250 #ifdef ASSERT 251 // Debug support for checking if code allows safepoints or not. 252 // Safepoints in the VM can happen because of allocation, invoking a VM operation, or blocking on 253 // mutex, or blocking on an object synchronizer (Java locking). 254 // If _no_safepoint_count is non-zero, then an assertion failure will happen in any of 255 // the above cases. The class NoSafepointVerifier is used to set this counter. 256 int _no_safepoint_count; // If 0, thread allow a safepoint to happen 257 258 public: 259 void inc_no_safepoint_count() { _no_safepoint_count++; } 260 void dec_no_safepoint_count() { _no_safepoint_count--; } 261 #endif // ASSERT 262 public: 263 // These functions check conditions before possibly going to a safepoint. 264 // including NoSafepointVerifier. 265 void check_for_valid_safepoint_state() NOT_DEBUG_RETURN; 266 void check_possible_safepoint() NOT_DEBUG_RETURN; 267 268 #ifdef ASSERT 269 private: 270 volatile uint64_t _visited_for_critical_count; 271 272 public: 273 void set_visited_for_critical_count(uint64_t safepoint_id) { 274 assert(_visited_for_critical_count == 0, "Must be reset before set"); 275 assert((safepoint_id & 0x1) == 1, "Must be odd"); 276 _visited_for_critical_count = safepoint_id; 277 } 278 void reset_visited_for_critical_count(uint64_t safepoint_id) { 279 assert(_visited_for_critical_count == safepoint_id, "Was not visited"); 280 _visited_for_critical_count = 0; 281 } 282 bool was_visited_for_critical_count(uint64_t safepoint_id) const { 283 return _visited_for_critical_count == safepoint_id; 284 } 285 #endif // ASSERT 286 287 // JavaThread termination support 288 public: 289 enum TerminatedTypes { 290 _not_terminated = 0xDEAD - 3, 291 _thread_exiting, // JavaThread::exit() has been called for this thread 292 _thread_gc_barrier_detached, // thread's GC barrier has been detached 293 _thread_terminated, // JavaThread is removed from thread list 294 _vm_exited // JavaThread is still executing native code, but VM is terminated 295 // only VM_Exit can set _vm_exited 296 }; 297 298 private: 299 // In general a JavaThread's _terminated field transitions as follows: 300 // 301 // _not_terminated => _thread_exiting => _thread_gc_barrier_detached => _thread_terminated 302 // 303 // _vm_exited is a special value to cover the case of a JavaThread 304 // executing native code after the VM itself is terminated. 305 // 306 // A JavaThread that fails to JNI attach has these _terminated field transitions: 307 // _not_terminated => _thread_terminated 308 // 309 volatile TerminatedTypes _terminated; 310 311 jint _in_deopt_handler; // count of deoptimization 312 // handlers thread is in 313 volatile bool _doing_unsafe_access; // Thread may fault due to unsafe access 314 bool _do_not_unlock_if_synchronized; // Do not unlock the receiver of a synchronized method (since it was 315 // never locked) when throwing an exception. Used by interpreter only. 316 #if INCLUDE_JVMTI 317 volatile bool _carrier_thread_suspended; // Carrier thread is externally suspended 318 bool _is_in_VTMS_transition; // thread is in virtual thread mount state transition 319 bool _is_in_tmp_VTMS_transition; // thread is in temporary virtual thread mount state transition 320 #ifdef ASSERT 321 bool _is_VTMS_transition_disabler; // thread currently disabled VTMS transitions 322 #endif 323 #endif 324 325 // JNI attach states: 326 enum JNIAttachStates { 327 _not_attaching_via_jni = 1, // thread is not attaching via JNI 328 _attaching_via_jni, // thread is attaching via JNI 329 _attached_via_jni // thread has attached via JNI 330 }; 331 332 // A regular JavaThread's _jni_attach_state is _not_attaching_via_jni. 333 // A native thread that is attaching via JNI starts with a value 334 // of _attaching_via_jni and transitions to _attached_via_jni. 335 volatile JNIAttachStates _jni_attach_state; 336 337 338 #if INCLUDE_JVMCI 339 // The _pending_* fields below are used to communicate extra information 340 // from an uncommon trap in JVMCI compiled code to the uncommon trap handler. 341 342 // Communicates the DeoptReason and DeoptAction of the uncommon trap 343 int _pending_deoptimization; 344 345 // Specifies whether the uncommon trap is to bci 0 of a synchronized method 346 // before the monitor has been acquired. 347 bool _pending_monitorenter; 348 349 // Specifies if the DeoptReason for the last uncommon trap was Reason_transfer_to_interpreter 350 bool _pending_transfer_to_interpreter; 351 352 // True if in a runtime call from compiled code that will deoptimize 353 // and re-execute a failed heap allocation in the interpreter. 354 bool _in_retryable_allocation; 355 356 // An id of a speculation that JVMCI compiled code can use to further describe and 357 // uniquely identify the speculative optimization guarded by an uncommon trap. 358 // See JVMCINMethodData::SPECULATION_LENGTH_BITS for further details. 359 jlong _pending_failed_speculation; 360 361 // These fields are mutually exclusive in terms of live ranges. 362 union { 363 // Communicates the pc at which the most recent implicit exception occurred 364 // from the signal handler to a deoptimization stub. 365 address _implicit_exception_pc; 366 367 // Communicates an alternative call target to an i2c stub from a JavaCall . 368 address _alternate_call_target; 369 } _jvmci; 370 371 // The JVMCIRuntime in a JVMCI shared library 372 JVMCIRuntime* _libjvmci_runtime; 373 374 // Support for high precision, thread sensitive counters in JVMCI compiled code. 375 jlong* _jvmci_counters; 376 377 // Fast thread locals for use by JVMCI 378 jlong _jvmci_reserved0; 379 jlong _jvmci_reserved1; 380 oop _jvmci_reserved_oop0; 381 382 public: 383 static jlong* _jvmci_old_thread_counters; 384 static void collect_counters(jlong* array, int length); 385 386 bool resize_counters(int current_size, int new_size); 387 388 static bool resize_all_jvmci_counters(int new_size); 389 390 void set_jvmci_reserved_oop0(oop value) { 391 _jvmci_reserved_oop0 = value; 392 } 393 394 oop get_jvmci_reserved_oop0() { 395 return _jvmci_reserved_oop0; 396 } 397 398 void set_jvmci_reserved0(jlong value) { 399 _jvmci_reserved0 = value; 400 } 401 402 jlong get_jvmci_reserved0() { 403 return _jvmci_reserved0; 404 } 405 406 void set_jvmci_reserved1(jlong value) { 407 _jvmci_reserved1 = value; 408 } 409 410 jlong get_jvmci_reserved1() { 411 return _jvmci_reserved1; 412 } 413 414 private: 415 #endif // INCLUDE_JVMCI 416 417 StackOverflow _stack_overflow_state; 418 419 // Compiler exception handling (NOTE: The _exception_oop is *NOT* the same as _pending_exception. It is 420 // used to temp. parsing values into and out of the runtime system during exception handling for compiled 421 // code) 422 volatile oop _exception_oop; // Exception thrown in compiled code 423 volatile address _exception_pc; // PC where exception happened 424 volatile address _exception_handler_pc; // PC for handler of exception 425 volatile int _is_method_handle_return; // true (== 1) if the current exception PC is a MethodHandle call site. 426 427 private: 428 // support for JNI critical regions 429 jint _jni_active_critical; // count of entries into JNI critical region 430 431 // Checked JNI: function name requires exception check 432 char* _pending_jni_exception_check_fn; 433 434 // For deadlock detection. 435 int _depth_first_number; 436 437 // JVMTI PopFrame support 438 // This is set to popframe_pending to signal that top Java frame should be popped immediately 439 int _popframe_condition; 440 441 // If reallocation of scalar replaced objects fails, we throw OOM 442 // and during exception propagation, pop the top 443 // _frames_to_pop_failed_realloc frames, the ones that reference 444 // failed reallocations. 445 int _frames_to_pop_failed_realloc; 446 447 ContinuationEntry* _cont_entry; 448 intptr_t* _cont_fastpath; // the sp of the oldest known interpreted/call_stub frame inside the 449 // continuation that we know about 450 int _cont_fastpath_thread_state; // whether global thread state allows continuation fastpath (JVMTI) 451 // It's signed for error detection. 452 #ifdef _LP64 453 int64_t _held_monitor_count; // used by continuations for fast lock detection 454 int64_t _jni_monitor_count; 455 #else 456 int32_t _held_monitor_count; // used by continuations for fast lock detection 457 int32_t _jni_monitor_count; 458 #endif 459 460 private: 461 462 friend class VMThread; 463 friend class ThreadWaitTransition; 464 friend class VM_Exit; 465 466 // Stack watermark barriers. 467 StackWatermarks _stack_watermarks; 468 469 public: 470 inline StackWatermarks* stack_watermarks() { return &_stack_watermarks; } 471 472 public: 473 // Constructor 474 JavaThread(); // delegating constructor 475 JavaThread(bool is_attaching_via_jni); // for main thread and JNI attached threads 476 JavaThread(ThreadFunction entry_point, size_t stack_size = 0); 477 ~JavaThread(); 478 479 #ifdef ASSERT 480 // verify this JavaThread hasn't be published in the Threads::list yet 481 void verify_not_published(); 482 #endif // ASSERT 483 484 StackOverflow* stack_overflow_state() { return &_stack_overflow_state; } 485 486 //JNI functiontable getter/setter for JVMTI jni function table interception API. 487 void set_jni_functions(struct JNINativeInterface_* functionTable) { 488 _jni_environment.functions = functionTable; 489 } 490 struct JNINativeInterface_* get_jni_functions() { 491 return (struct JNINativeInterface_ *)_jni_environment.functions; 492 } 493 494 // This function is called at thread creation to allow 495 // platform specific thread variables to be initialized. 496 void cache_global_variables(); 497 498 // Executes Shutdown.shutdown() 499 void invoke_shutdown_hooks(); 500 501 // Cleanup on thread exit 502 enum ExitType { 503 normal_exit, 504 jni_detach 505 }; 506 void exit(bool destroy_vm, ExitType exit_type = normal_exit); 507 508 void cleanup_failed_attach_current_thread(bool is_daemon); 509 510 // Testers 511 virtual bool is_Java_thread() const { return true; } 512 virtual bool can_call_java() const { return true; } 513 514 virtual bool is_active_Java_thread() const { 515 return on_thread_list() && !is_terminated(); 516 } 517 518 // Thread oop. threadObj() can be null for initial JavaThread 519 // (or for threads attached via JNI) 520 oop threadObj() const; 521 void set_threadOopHandles(oop p); 522 oop vthread() const; 523 void set_vthread(oop p); 524 oop scopedValueCache() const; 525 void set_scopedValueCache(oop p); 526 void clear_scopedValueBindings(); 527 oop jvmti_vthread() const; 528 void set_jvmti_vthread(oop p); 529 530 // Prepare thread and add to priority queue. If a priority is 531 // not specified, use the priority of the thread object. Threads_lock 532 // must be held while this function is called. 533 void prepare(jobject jni_thread, ThreadPriority prio=NoPriority); 534 535 void set_saved_exception_pc(address pc) { _saved_exception_pc = pc; } 536 address saved_exception_pc() { return _saved_exception_pc; } 537 538 ThreadFunction entry_point() const { return _entry_point; } 539 540 // Allocates a new Java level thread object for this thread. thread_name may be null. 541 void allocate_threadObj(Handle thread_group, const char* thread_name, bool daemon, TRAPS); 542 543 // Last frame anchor routines 544 545 JavaFrameAnchor* frame_anchor(void) { return &_anchor; } 546 547 // last_Java_sp 548 bool has_last_Java_frame() const { return _anchor.has_last_Java_frame(); } 549 intptr_t* last_Java_sp() const { return _anchor.last_Java_sp(); } 550 551 // last_Java_pc 552 553 address last_Java_pc(void) { return _anchor.last_Java_pc(); } 554 555 // Safepoint support 556 inline JavaThreadState thread_state() const; 557 inline void set_thread_state(JavaThreadState s); 558 inline void set_thread_state_fence(JavaThreadState s); // fence after setting thread state 559 inline ThreadSafepointState* safepoint_state() const; 560 inline void set_safepoint_state(ThreadSafepointState* state); 561 inline bool is_at_poll_safepoint(); 562 563 // JavaThread termination and lifecycle support: 564 void smr_delete(); 565 bool on_thread_list() const { return _on_thread_list; } 566 void set_on_thread_list() { _on_thread_list = true; } 567 568 // thread has called JavaThread::exit(), thread's GC barrier is detached 569 // or thread is terminated 570 bool is_exiting() const; 571 // thread's GC barrier is NOT detached and thread is NOT terminated 572 bool is_oop_safe() const; 573 // thread is terminated (no longer on the threads list); the thread must 574 // be protected by a ThreadsListHandle to avoid potential crashes. 575 bool check_is_terminated(TerminatedTypes l_terminated) const { 576 return l_terminated == _thread_terminated || l_terminated == _vm_exited; 577 } 578 bool is_terminated() const; 579 void set_terminated(TerminatedTypes t); 580 581 void block_if_vm_exited(); 582 583 bool doing_unsafe_access() { return _doing_unsafe_access; } 584 void set_doing_unsafe_access(bool val) { _doing_unsafe_access = val; } 585 586 bool do_not_unlock_if_synchronized() { return _do_not_unlock_if_synchronized; } 587 void set_do_not_unlock_if_synchronized(bool val) { _do_not_unlock_if_synchronized = val; } 588 589 SafepointMechanism::ThreadData* poll_data() { return &_poll_data; } 590 591 void set_requires_cross_modify_fence(bool val) PRODUCT_RETURN NOT_PRODUCT({ _requires_cross_modify_fence = val; }) 592 593 // Continuation support 594 ContinuationEntry* last_continuation() const { return _cont_entry; } 595 void set_cont_fastpath(intptr_t* x) { _cont_fastpath = x; } 596 void push_cont_fastpath(intptr_t* sp) { if (sp > _cont_fastpath) _cont_fastpath = sp; } 597 void set_cont_fastpath_thread_state(bool x) { _cont_fastpath_thread_state = (int)x; } 598 intptr_t* raw_cont_fastpath() const { return _cont_fastpath; } 599 bool cont_fastpath() const { return _cont_fastpath == nullptr && _cont_fastpath_thread_state != 0; } 600 bool cont_fastpath_thread_state() const { return _cont_fastpath_thread_state != 0; } 601 602 void inc_held_monitor_count(int i = 1, bool jni = false); 603 void dec_held_monitor_count(int i = 1, bool jni = false); 604 605 int64_t held_monitor_count() { return (int64_t)_held_monitor_count; } 606 int64_t jni_monitor_count() { return (int64_t)_jni_monitor_count; } 607 void clear_jni_monitor_count() { _jni_monitor_count = 0; } 608 609 inline bool is_vthread_mounted() const; 610 inline const ContinuationEntry* vthread_continuation() const; 611 612 private: 613 DEBUG_ONLY(void verify_frame_info();) 614 615 // Support for thread handshake operations 616 HandshakeState _handshake; 617 public: 618 HandshakeState* handshake_state() { return &_handshake; } 619 620 // A JavaThread can always safely operate on it self and other threads 621 // can do it safely if they are the active handshaker. 622 bool is_handshake_safe_for(Thread* th) const { 623 return _handshake.active_handshaker() == th || this == th; 624 } 625 626 // Suspend/resume support for JavaThread 627 // higher-level suspension/resume logic called by the public APIs 628 bool java_suspend(); 629 bool java_resume(); 630 bool is_suspended() { return _handshake.is_suspended(); } 631 632 // Check for async exception in addition to safepoint. 633 static void check_special_condition_for_native_trans(JavaThread *thread); 634 635 // Synchronize with another thread that is deoptimizing objects of the 636 // current thread, i.e. reverts optimizations based on escape analysis. 637 void wait_for_object_deoptimization(); 638 639 #if INCLUDE_JVMTI 640 inline void set_carrier_thread_suspended(); 641 inline void clear_carrier_thread_suspended(); 642 643 bool is_carrier_thread_suspended() const { 644 return _carrier_thread_suspended; 645 } 646 647 bool is_in_VTMS_transition() const { return _is_in_VTMS_transition; } 648 bool is_in_tmp_VTMS_transition() const { return _is_in_tmp_VTMS_transition; } 649 bool is_in_any_VTMS_transition() const { return _is_in_VTMS_transition || _is_in_tmp_VTMS_transition; } 650 651 void set_is_in_VTMS_transition(bool val); 652 void toggle_is_in_tmp_VTMS_transition() { _is_in_tmp_VTMS_transition = !_is_in_tmp_VTMS_transition; }; 653 654 #ifdef ASSERT 655 bool is_VTMS_transition_disabler() const { return _is_VTMS_transition_disabler; } 656 void set_is_VTMS_transition_disabler(bool val); 657 #endif 658 #endif 659 660 // Support for object deoptimization and JFR suspension 661 void handle_special_runtime_exit_condition(); 662 bool has_special_runtime_exit_condition() { 663 return (_suspend_flags & (_obj_deopt JFR_ONLY(| _trace_flag))) != 0; 664 } 665 666 // Fast-locking support 667 bool is_lock_owned(address adr) const; 668 669 // Accessors for vframe array top 670 // The linked list of vframe arrays are sorted on sp. This means when we 671 // unpack the head must contain the vframe array to unpack. 672 void set_vframe_array_head(vframeArray* value) { _vframe_array_head = value; } 673 vframeArray* vframe_array_head() const { return _vframe_array_head; } 674 675 // Side structure for deferring update of java frame locals until deopt occurs 676 JvmtiDeferredUpdates* deferred_updates() const { return _jvmti_deferred_updates; } 677 void set_deferred_updates(JvmtiDeferredUpdates* du) { _jvmti_deferred_updates = du; } 678 679 // These only really exist to make debugging deopt problems simpler 680 681 void set_vframe_array_last(vframeArray* value) { _vframe_array_last = value; } 682 vframeArray* vframe_array_last() const { return _vframe_array_last; } 683 684 // The special resourceMark used during deoptimization 685 686 void set_deopt_mark(DeoptResourceMark* value) { _deopt_mark = value; } 687 DeoptResourceMark* deopt_mark(void) { return _deopt_mark; } 688 689 void set_deopt_compiled_method(CompiledMethod* nm) { _deopt_nmethod = nm; } 690 CompiledMethod* deopt_compiled_method() { return _deopt_nmethod; } 691 692 Method* callee_target() const { return _callee_target; } 693 void set_callee_target (Method* x) { _callee_target = x; } 694 695 // Oop results of vm runtime calls 696 oop vm_result() const { return _vm_result; } 697 void set_vm_result (oop x) { _vm_result = x; } 698 699 void set_vm_result_2 (Metadata* x) { _vm_result_2 = x; } 700 701 MemRegion deferred_card_mark() const { return _deferred_card_mark; } 702 void set_deferred_card_mark(MemRegion mr) { _deferred_card_mark = mr; } 703 704 #if INCLUDE_JVMCI 705 jlong pending_failed_speculation() const { return _pending_failed_speculation; } 706 void set_pending_monitorenter(bool b) { _pending_monitorenter = b; } 707 void set_pending_deoptimization(int reason) { _pending_deoptimization = reason; } 708 void set_pending_failed_speculation(jlong failed_speculation) { _pending_failed_speculation = failed_speculation; } 709 void set_pending_transfer_to_interpreter(bool b) { _pending_transfer_to_interpreter = b; } 710 void set_jvmci_alternate_call_target(address a) { assert(_jvmci._alternate_call_target == nullptr, "must be"); _jvmci._alternate_call_target = a; } 711 void set_jvmci_implicit_exception_pc(address a) { assert(_jvmci._implicit_exception_pc == nullptr, "must be"); _jvmci._implicit_exception_pc = a; } 712 713 virtual bool in_retryable_allocation() const { return _in_retryable_allocation; } 714 void set_in_retryable_allocation(bool b) { _in_retryable_allocation = b; } 715 716 JVMCIRuntime* libjvmci_runtime() const { return _libjvmci_runtime; } 717 void set_libjvmci_runtime(JVMCIRuntime* rt) { 718 assert((_libjvmci_runtime == nullptr && rt != nullptr) || (_libjvmci_runtime != nullptr && rt == nullptr), "must be"); 719 _libjvmci_runtime = rt; 720 } 721 #endif // INCLUDE_JVMCI 722 723 // Exception handling for compiled methods 724 oop exception_oop() const; 725 address exception_pc() const { return _exception_pc; } 726 727 void set_exception_oop(oop o); 728 void set_exception_pc(address a) { _exception_pc = a; } 729 void set_exception_handler_pc(address a) { _exception_handler_pc = a; } 730 void set_is_method_handle_return(bool value) { _is_method_handle_return = value ? 1 : 0; } 731 732 void clear_exception_oop_and_pc() { 733 set_exception_oop(nullptr); 734 set_exception_pc(nullptr); 735 } 736 737 // Check if address is in the usable part of the stack (excludes protected 738 // guard pages). Can be applied to any thread and is an approximation for 739 // using is_in_live_stack when the query has to happen from another thread. 740 bool is_in_usable_stack(address adr) const { 741 return is_in_stack_range_incl(adr, _stack_overflow_state.stack_reserved_zone_base()); 742 } 743 744 // Misc. accessors/mutators 745 static ByteSize scopedValueCache_offset() { return byte_offset_of(JavaThread, _scopedValueCache); } 746 747 // For assembly stub generation 748 static ByteSize threadObj_offset() { return byte_offset_of(JavaThread, _threadObj); } 749 static ByteSize vthread_offset() { return byte_offset_of(JavaThread, _vthread); } 750 static ByteSize jni_environment_offset() { return byte_offset_of(JavaThread, _jni_environment); } 751 static ByteSize pending_jni_exception_check_fn_offset() { 752 return byte_offset_of(JavaThread, _pending_jni_exception_check_fn); 753 } 754 static ByteSize last_Java_sp_offset() { 755 return byte_offset_of(JavaThread, _anchor) + JavaFrameAnchor::last_Java_sp_offset(); 756 } 757 static ByteSize last_Java_pc_offset() { 758 return byte_offset_of(JavaThread, _anchor) + JavaFrameAnchor::last_Java_pc_offset(); 759 } 760 static ByteSize frame_anchor_offset() { 761 return byte_offset_of(JavaThread, _anchor); 762 } 763 static ByteSize callee_target_offset() { return byte_offset_of(JavaThread, _callee_target); } 764 static ByteSize vm_result_offset() { return byte_offset_of(JavaThread, _vm_result); } 765 static ByteSize vm_result_2_offset() { return byte_offset_of(JavaThread, _vm_result_2); } 766 static ByteSize thread_state_offset() { return byte_offset_of(JavaThread, _thread_state); } 767 static ByteSize polling_word_offset() { return byte_offset_of(JavaThread, _poll_data) + byte_offset_of(SafepointMechanism::ThreadData, _polling_word);} 768 static ByteSize polling_page_offset() { return byte_offset_of(JavaThread, _poll_data) + byte_offset_of(SafepointMechanism::ThreadData, _polling_page);} 769 static ByteSize saved_exception_pc_offset() { return byte_offset_of(JavaThread, _saved_exception_pc); } 770 static ByteSize osthread_offset() { return byte_offset_of(JavaThread, _osthread); } 771 #if INCLUDE_JVMCI 772 static ByteSize pending_deoptimization_offset() { return byte_offset_of(JavaThread, _pending_deoptimization); } 773 static ByteSize pending_monitorenter_offset() { return byte_offset_of(JavaThread, _pending_monitorenter); } 774 static ByteSize jvmci_alternate_call_target_offset() { return byte_offset_of(JavaThread, _jvmci._alternate_call_target); } 775 static ByteSize jvmci_implicit_exception_pc_offset() { return byte_offset_of(JavaThread, _jvmci._implicit_exception_pc); } 776 static ByteSize jvmci_counters_offset() { return byte_offset_of(JavaThread, _jvmci_counters); } 777 #endif // INCLUDE_JVMCI 778 static ByteSize exception_oop_offset() { return byte_offset_of(JavaThread, _exception_oop); } 779 static ByteSize exception_pc_offset() { return byte_offset_of(JavaThread, _exception_pc); } 780 static ByteSize exception_handler_pc_offset() { return byte_offset_of(JavaThread, _exception_handler_pc); } 781 static ByteSize is_method_handle_return_offset() { return byte_offset_of(JavaThread, _is_method_handle_return); } 782 783 static ByteSize active_handles_offset() { return byte_offset_of(JavaThread, _active_handles); } 784 785 // StackOverflow offsets 786 static ByteSize stack_overflow_limit_offset() { 787 return byte_offset_of(JavaThread, _stack_overflow_state._stack_overflow_limit); 788 } 789 static ByteSize stack_guard_state_offset() { 790 return byte_offset_of(JavaThread, _stack_overflow_state._stack_guard_state); 791 } 792 static ByteSize reserved_stack_activation_offset() { 793 return byte_offset_of(JavaThread, _stack_overflow_state._reserved_stack_activation); 794 } 795 static ByteSize shadow_zone_safe_limit() { 796 return byte_offset_of(JavaThread, _stack_overflow_state._shadow_zone_safe_limit); 797 } 798 static ByteSize shadow_zone_growth_watermark() { 799 return byte_offset_of(JavaThread, _stack_overflow_state._shadow_zone_growth_watermark); 800 } 801 802 static ByteSize suspend_flags_offset() { return byte_offset_of(JavaThread, _suspend_flags); } 803 804 static ByteSize do_not_unlock_if_synchronized_offset() { return byte_offset_of(JavaThread, _do_not_unlock_if_synchronized); } 805 static ByteSize should_post_on_exceptions_flag_offset() { 806 return byte_offset_of(JavaThread, _should_post_on_exceptions_flag); 807 } 808 static ByteSize doing_unsafe_access_offset() { return byte_offset_of(JavaThread, _doing_unsafe_access); } 809 NOT_PRODUCT(static ByteSize requires_cross_modify_fence_offset() { return byte_offset_of(JavaThread, _requires_cross_modify_fence); }) 810 811 static ByteSize cont_entry_offset() { return byte_offset_of(JavaThread, _cont_entry); } 812 static ByteSize cont_fastpath_offset() { return byte_offset_of(JavaThread, _cont_fastpath); } 813 static ByteSize held_monitor_count_offset() { return byte_offset_of(JavaThread, _held_monitor_count); } 814 815 // Returns the jni environment for this thread 816 JNIEnv* jni_environment() { return &_jni_environment; } 817 818 // Returns the current thread as indicated by the given JNIEnv. 819 // We don't assert it is Thread::current here as that is done at the 820 // external JNI entry points where the JNIEnv is passed into the VM. 821 static JavaThread* thread_from_jni_environment(JNIEnv* env) { 822 JavaThread* current = reinterpret_cast<JavaThread*>(((intptr_t)env - in_bytes(jni_environment_offset()))); 823 // We can't normally get here in a thread that has completed its 824 // execution and so "is_terminated", except when the call is from 825 // AsyncGetCallTrace, which can be triggered by a signal at any point in 826 // a thread's lifecycle. A thread is also considered terminated if the VM 827 // has exited, so we have to check this and block in case this is a daemon 828 // thread returning to the VM (the JNI DirectBuffer entry points rely on 829 // this). 830 if (current->is_terminated()) { 831 current->block_if_vm_exited(); 832 } 833 return current; 834 } 835 836 // JNI critical regions. These can nest. 837 bool in_critical() { return _jni_active_critical > 0; } 838 bool in_last_critical() { return _jni_active_critical == 1; } 839 inline void enter_critical(); 840 void exit_critical() { 841 assert(Thread::current() == this, "this must be current thread"); 842 _jni_active_critical--; 843 assert(_jni_active_critical >= 0, "JNI critical nesting problem?"); 844 } 845 846 // Checked JNI: is the programmer required to check for exceptions, if so specify 847 // which function name. Returning to a Java frame should implicitly clear the 848 // pending check, this is done for Native->Java transitions (i.e. user JNI code). 849 // VM->Java transitions are not cleared, it is expected that JNI code enclosed 850 // within ThreadToNativeFromVM makes proper exception checks (i.e. VM internal). 851 bool is_pending_jni_exception_check() const { return _pending_jni_exception_check_fn != nullptr; } 852 void clear_pending_jni_exception_check() { _pending_jni_exception_check_fn = nullptr; } 853 const char* get_pending_jni_exception_check() const { return _pending_jni_exception_check_fn; } 854 void set_pending_jni_exception_check(const char* fn_name) { _pending_jni_exception_check_fn = (char*) fn_name; } 855 856 // For deadlock detection 857 int depth_first_number() { return _depth_first_number; } 858 void set_depth_first_number(int dfn) { _depth_first_number = dfn; } 859 860 private: 861 void set_monitor_chunks(MonitorChunk* monitor_chunks) { _monitor_chunks = monitor_chunks; } 862 863 public: 864 MonitorChunk* monitor_chunks() const { return _monitor_chunks; } 865 void add_monitor_chunk(MonitorChunk* chunk); 866 void remove_monitor_chunk(MonitorChunk* chunk); 867 bool in_deopt_handler() const { return _in_deopt_handler > 0; } 868 void inc_in_deopt_handler() { _in_deopt_handler++; } 869 void dec_in_deopt_handler() { 870 assert(_in_deopt_handler > 0, "mismatched deopt nesting"); 871 if (_in_deopt_handler > 0) { // robustness 872 _in_deopt_handler--; 873 } 874 } 875 876 private: 877 void set_entry_point(ThreadFunction entry_point) { _entry_point = entry_point; } 878 879 // factor out low-level mechanics for use in both normal and error cases 880 const char* get_thread_name_string(char* buf = nullptr, int buflen = 0) const; 881 882 public: 883 884 // Frame iteration; calls the function f for all frames on the stack 885 void frames_do(void f(frame*, const RegisterMap*)); 886 887 // Memory operations 888 void oops_do_frames(OopClosure* f, CodeBlobClosure* cf); 889 void oops_do_no_frames(OopClosure* f, CodeBlobClosure* cf); 890 891 // GC operations 892 virtual void nmethods_do(CodeBlobClosure* cf); 893 894 // RedefineClasses Support 895 void metadata_do(MetadataClosure* f); 896 897 // Debug method asserting thread states are correct during a handshake operation. 898 DEBUG_ONLY(void verify_states_for_handshake();) 899 900 // Misc. operations 901 const char* name() const; 902 const char* type_name() const { return "JavaThread"; } 903 static const char* name_for(oop thread_obj); 904 905 void print_on(outputStream* st, bool print_extended_info) const; 906 void print_on(outputStream* st) const { print_on(st, false); } 907 void print() const; 908 void print_thread_state_on(outputStream*) const; 909 void print_on_error(outputStream* st, char* buf, int buflen) const; 910 void print_name_on_error(outputStream* st, char* buf, int buflen) const; 911 void verify(); 912 913 // Accessing frames 914 frame last_frame() { 915 _anchor.make_walkable(); 916 return pd_last_frame(); 917 } 918 javaVFrame* last_java_vframe(RegisterMap* reg_map) { return last_java_vframe(last_frame(), reg_map); } 919 920 frame carrier_last_frame(RegisterMap* reg_map); 921 javaVFrame* carrier_last_java_vframe(RegisterMap* reg_map) { return last_java_vframe(carrier_last_frame(reg_map), reg_map); } 922 923 frame vthread_last_frame(); 924 javaVFrame* vthread_last_java_vframe(RegisterMap* reg_map) { return last_java_vframe(vthread_last_frame(), reg_map); } 925 926 frame platform_thread_last_frame(RegisterMap* reg_map); 927 javaVFrame* platform_thread_last_java_vframe(RegisterMap* reg_map) { 928 return last_java_vframe(platform_thread_last_frame(reg_map), reg_map); 929 } 930 931 javaVFrame* last_java_vframe(const frame f, RegisterMap* reg_map); 932 933 // Returns method at 'depth' java or native frames down the stack 934 // Used for security checks 935 Klass* security_get_caller_class(int depth); 936 937 // Print stack trace in external format 938 // These variants print carrier/platform thread information only. 939 void print_stack_on(outputStream* st); 940 void print_stack() { print_stack_on(tty); } 941 // This prints the currently mounted virtual thread. 942 void print_vthread_stack_on(outputStream* st); 943 // This prints the active stack: either carrier/platform or virtual. 944 void print_active_stack_on(outputStream* st); 945 // Print current stack trace for checked JNI warnings and JNI fatal errors. 946 // This is the external format from above, but selecting the platform 947 // or vthread as applicable. 948 void print_jni_stack(); 949 950 // Print stack traces in various internal formats 951 void trace_stack() PRODUCT_RETURN; 952 void trace_stack_from(vframe* start_vf) PRODUCT_RETURN; 953 void trace_frames() PRODUCT_RETURN; 954 955 // Print an annotated view of the stack frames 956 void print_frame_layout(int depth = 0, bool validate_only = false) NOT_DEBUG_RETURN; 957 void validate_frame_layout() { 958 print_frame_layout(0, true); 959 } 960 961 // Function for testing deoptimization 962 void deoptimize(); 963 void make_zombies(); 964 965 void deoptimize_marked_methods(); 966 967 public: 968 // Returns the running thread as a JavaThread 969 static JavaThread* current() { 970 return JavaThread::cast(Thread::current()); 971 } 972 973 // Returns the current thread as a JavaThread, or nullptr if not attached 974 static inline JavaThread* current_or_null(); 975 976 // Casts 977 static JavaThread* cast(Thread* t) { 978 assert(t->is_Java_thread(), "incorrect cast to JavaThread"); 979 return static_cast<JavaThread*>(t); 980 } 981 982 static const JavaThread* cast(const Thread* t) { 983 assert(t->is_Java_thread(), "incorrect cast to const JavaThread"); 984 return static_cast<const JavaThread*>(t); 985 } 986 987 // Returns the active Java thread. Do not use this if you know you are calling 988 // from a JavaThread, as it's slower than JavaThread::current. If called from 989 // the VMThread, it also returns the JavaThread that instigated the VMThread's 990 // operation. You may not want that either. 991 static JavaThread* active(); 992 993 protected: 994 virtual void pre_run(); 995 virtual void run(); 996 void thread_main_inner(); 997 virtual void post_run(); 998 999 public: 1000 // Thread local information maintained by JVMTI. 1001 void set_jvmti_thread_state(JvmtiThreadState *value) { _jvmti_thread_state = value; } 1002 // A JvmtiThreadState is lazily allocated. This jvmti_thread_state() 1003 // getter is used to get this JavaThread's JvmtiThreadState if it has 1004 // one which means null can be returned. JvmtiThreadState::state_for() 1005 // is used to get the specified JavaThread's JvmtiThreadState if it has 1006 // one or it allocates a new JvmtiThreadState for the JavaThread and 1007 // returns it. JvmtiThreadState::state_for() will return null only if 1008 // the specified JavaThread is exiting. 1009 JvmtiThreadState *jvmti_thread_state() const { return _jvmti_thread_state; } 1010 static ByteSize jvmti_thread_state_offset() { return byte_offset_of(JavaThread, _jvmti_thread_state); } 1011 1012 #if INCLUDE_JVMTI 1013 // Rebind JVMTI thread state from carrier to virtual or from virtual to carrier. 1014 JvmtiThreadState *rebind_to_jvmti_thread_state_of(oop thread_oop); 1015 #endif 1016 1017 // JVMTI PopFrame support 1018 // Setting and clearing popframe_condition 1019 // All of these enumerated values are bits. popframe_pending 1020 // indicates that a PopFrame() has been requested and not yet been 1021 // completed. popframe_processing indicates that that PopFrame() is in 1022 // the process of being completed. popframe_force_deopt_reexecution_bit 1023 // indicates that special handling is required when returning to a 1024 // deoptimized caller. 1025 enum PopCondition { 1026 popframe_inactive = 0x00, 1027 popframe_pending_bit = 0x01, 1028 popframe_processing_bit = 0x02, 1029 popframe_force_deopt_reexecution_bit = 0x04 1030 }; 1031 PopCondition popframe_condition() { return (PopCondition) _popframe_condition; } 1032 void set_popframe_condition(PopCondition c) { _popframe_condition = c; } 1033 void set_popframe_condition_bit(PopCondition c) { _popframe_condition |= c; } 1034 void clear_popframe_condition() { _popframe_condition = popframe_inactive; } 1035 static ByteSize popframe_condition_offset() { return byte_offset_of(JavaThread, _popframe_condition); } 1036 bool has_pending_popframe() { return (popframe_condition() & popframe_pending_bit) != 0; } 1037 bool popframe_forcing_deopt_reexecution() { return (popframe_condition() & popframe_force_deopt_reexecution_bit) != 0; } 1038 1039 bool pop_frame_in_process(void) { return ((_popframe_condition & popframe_processing_bit) != 0); } 1040 void set_pop_frame_in_process(void) { _popframe_condition |= popframe_processing_bit; } 1041 void clr_pop_frame_in_process(void) { _popframe_condition &= ~popframe_processing_bit; } 1042 1043 int frames_to_pop_failed_realloc() const { return _frames_to_pop_failed_realloc; } 1044 void set_frames_to_pop_failed_realloc(int nb) { _frames_to_pop_failed_realloc = nb; } 1045 void dec_frames_to_pop_failed_realloc() { _frames_to_pop_failed_realloc--; } 1046 1047 private: 1048 // Saved incoming arguments to popped frame. 1049 // Used only when popped interpreted frame returns to deoptimized frame. 1050 void* _popframe_preserved_args; 1051 int _popframe_preserved_args_size; 1052 1053 public: 1054 void popframe_preserve_args(ByteSize size_in_bytes, void* start); 1055 void* popframe_preserved_args(); 1056 ByteSize popframe_preserved_args_size(); 1057 WordSize popframe_preserved_args_size_in_words(); 1058 void popframe_free_preserved_args(); 1059 1060 1061 private: 1062 JvmtiThreadState *_jvmti_thread_state; 1063 1064 // Used by the interpreter in fullspeed mode for frame pop, method 1065 // entry, method exit and single stepping support. This field is 1066 // only set to non-zero at a safepoint or using a direct handshake 1067 // (see EnterInterpOnlyModeClosure). 1068 // It can be set to zero asynchronously to this threads execution (i.e., without 1069 // safepoint/handshake or a lock) so we have to be very careful. 1070 // Accesses by other threads are synchronized using JvmtiThreadState_lock though. 1071 int _interp_only_mode; 1072 1073 public: 1074 // used by the interpreter for fullspeed debugging support (see above) 1075 static ByteSize interp_only_mode_offset() { return byte_offset_of(JavaThread, _interp_only_mode); } 1076 bool is_interp_only_mode() { return (_interp_only_mode != 0); } 1077 int get_interp_only_mode() { return _interp_only_mode; } 1078 int set_interp_only_mode(int val) { return _interp_only_mode = val; } 1079 void increment_interp_only_mode() { ++_interp_only_mode; } 1080 void decrement_interp_only_mode() { --_interp_only_mode; } 1081 1082 // support for cached flag that indicates whether exceptions need to be posted for this thread 1083 // if this is false, we can avoid deoptimizing when events are thrown 1084 // this gets set to reflect whether jvmtiExport::post_exception_throw would actually do anything 1085 private: 1086 int _should_post_on_exceptions_flag; 1087 1088 public: 1089 void set_should_post_on_exceptions_flag(int val) { _should_post_on_exceptions_flag = val; } 1090 1091 private: 1092 ThreadStatistics *_thread_stat; 1093 1094 public: 1095 ThreadStatistics* get_thread_stat() const { return _thread_stat; } 1096 1097 // Return a blocker object for which this thread is blocked parking. 1098 oop current_park_blocker(); 1099 1100 private: 1101 static size_t _stack_size_at_create; 1102 1103 public: 1104 static inline size_t stack_size_at_create(void) { 1105 return _stack_size_at_create; 1106 } 1107 static inline void set_stack_size_at_create(size_t value) { 1108 _stack_size_at_create = value; 1109 } 1110 1111 // Machine dependent stuff 1112 #include OS_CPU_HEADER(javaThread) 1113 1114 // JSR166 per-thread parker 1115 private: 1116 Parker _parker; 1117 public: 1118 Parker* parker() { return &_parker; } 1119 1120 public: 1121 // clearing/querying jni attach status 1122 bool is_attaching_via_jni() const { return _jni_attach_state == _attaching_via_jni; } 1123 bool has_attached_via_jni() const { return is_attaching_via_jni() || _jni_attach_state == _attached_via_jni; } 1124 inline void set_done_attaching_via_jni(); 1125 1126 // Stack dump assistance: 1127 // Track the class we want to initialize but for which we have to wait 1128 // on its init_lock() because it is already being initialized. 1129 void set_class_to_be_initialized(InstanceKlass* k); 1130 InstanceKlass* class_to_be_initialized() const; 1131 1132 private: 1133 InstanceKlass* _class_to_be_initialized; 1134 1135 // java.lang.Thread.sleep support 1136 ParkEvent * _SleepEvent; 1137 public: 1138 bool sleep(jlong millis); 1139 1140 // java.lang.Thread interruption support 1141 void interrupt(); 1142 bool is_interrupted(bool clear_interrupted); 1143 1144 private: 1145 LockStack _lock_stack; 1146 1147 public: 1148 LockStack& lock_stack() { return _lock_stack; } 1149 1150 static ByteSize lock_stack_current_offset() { return byte_offset_of(JavaThread, _lock_stack) + LockStack::current_offset(); } 1151 static ByteSize lock_stack_limit_offset() { return byte_offset_of(JavaThread, _lock_stack) + LockStack::limit_offset(); } 1152 1153 1154 static OopStorage* thread_oop_storage(); 1155 1156 static void verify_cross_modify_fence_failure(JavaThread *thread) PRODUCT_RETURN; 1157 1158 // Helper function to create the java.lang.Thread object for a 1159 // VM-internal thread. The thread will have the given name, be 1160 // part of the System ThreadGroup and if is_visible is true will be 1161 // discoverable via the system ThreadGroup. 1162 static Handle create_system_thread_object(const char* name, bool is_visible, TRAPS); 1163 1164 // Helper function to start a VM-internal daemon thread. 1165 // E.g. ServiceThread, NotificationThread, CompilerThread etc. 1166 static void start_internal_daemon(JavaThread* current, JavaThread* target, 1167 Handle thread_oop, ThreadPriority prio); 1168 1169 // Helper function to do vm_exit_on_initialization for osthread 1170 // resource allocation failure. 1171 static void vm_exit_on_osthread_failure(JavaThread* thread); 1172 1173 // Deferred OopHandle release support 1174 private: 1175 // List of OopHandles to be released - guarded by the Service_lock. 1176 static OopHandleList* _oop_handle_list; 1177 // Add our OopHandles to the list for the service thread to release. 1178 void add_oop_handles_for_release(); 1179 // Called by the ServiceThread to release the OopHandles. 1180 static void release_oop_handles(); 1181 // Called by the ServiceThread to poll if there are any OopHandles to release. 1182 // Called when holding the Service_lock. 1183 static bool has_oop_handles_to_release() { 1184 return _oop_handle_list != nullptr; 1185 } 1186 }; 1187 1188 inline JavaThread* JavaThread::current_or_null() { 1189 Thread* current = Thread::current_or_null(); 1190 return current != nullptr ? JavaThread::cast(current) : nullptr; 1191 } 1192 1193 class UnlockFlagSaver { 1194 private: 1195 JavaThread* _thread; 1196 bool _do_not_unlock; 1197 public: 1198 UnlockFlagSaver(JavaThread* t) { 1199 _thread = t; 1200 _do_not_unlock = t->do_not_unlock_if_synchronized(); 1201 t->set_do_not_unlock_if_synchronized(false); 1202 } 1203 ~UnlockFlagSaver() { 1204 _thread->set_do_not_unlock_if_synchronized(_do_not_unlock); 1205 } 1206 }; 1207 1208 class JNIHandleMark : public StackObj { 1209 JavaThread* _thread; 1210 public: 1211 JNIHandleMark(JavaThread* thread) : _thread(thread) { 1212 thread->push_jni_handle_block(); 1213 } 1214 ~JNIHandleMark() { _thread->pop_jni_handle_block(); } 1215 }; 1216 1217 #endif // SHARE_RUNTIME_JAVATHREAD_HPP