1 /* 2 * Copyright (c) 1997, 2024, Oracle and/or its affiliates. All rights reserved. 3 * Copyright (c) 2021, Azul Systems, Inc. All rights reserved. 4 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 5 * 6 * This code is free software; you can redistribute it and/or modify it 7 * under the terms of the GNU General Public License version 2 only, as 8 * published by the Free Software Foundation. 9 * 10 * This code is distributed in the hope that it will be useful, but WITHOUT 11 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 12 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 13 * version 2 for more details (a copy is included in the LICENSE file that 14 * accompanied this code). 15 * 16 * You should have received a copy of the GNU General Public License version 17 * 2 along with this work; if not, write to the Free Software Foundation, 18 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 19 * 20 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 21 * or visit www.oracle.com if you need additional information or have any 22 * questions. 23 * 24 */ 25 26 #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 oop _return_buffered_value; // buffered value being returned 145 146 // See ReduceInitialCardMarks: this holds the precise space interval of 147 // the most recent slow path allocation for which compiled code has 148 // elided card-marks for performance along the fast-path. 149 MemRegion _deferred_card_mark; 150 151 ObjectMonitor* volatile _current_pending_monitor; // ObjectMonitor this thread is waiting to lock 152 bool _current_pending_monitor_is_from_java; // locking is from Java code 153 ObjectMonitor* volatile _current_waiting_monitor; // ObjectMonitor on which this thread called Object.wait() 154 155 // Active_handles points to a block of handles 156 JNIHandleBlock* _active_handles; 157 158 // One-element thread local free list 159 JNIHandleBlock* _free_handle_block; 160 161 public: 162 // For tracking the heavyweight monitor the thread is pending on. 163 ObjectMonitor* current_pending_monitor() { 164 // Use Atomic::load() to prevent data race between concurrent modification and 165 // concurrent readers, e.g. ThreadService::get_current_contended_monitor(). 166 // Especially, reloading pointer from thread after null check must be prevented. 167 return Atomic::load(&_current_pending_monitor); 168 } 169 void set_current_pending_monitor(ObjectMonitor* monitor) { 170 Atomic::store(&_current_pending_monitor, monitor); 171 } 172 void set_current_pending_monitor_is_from_java(bool from_java) { 173 _current_pending_monitor_is_from_java = from_java; 174 } 175 bool current_pending_monitor_is_from_java() { 176 return _current_pending_monitor_is_from_java; 177 } 178 ObjectMonitor* current_waiting_monitor() { 179 // See the comment in current_pending_monitor() above. 180 return Atomic::load(&_current_waiting_monitor); 181 } 182 void set_current_waiting_monitor(ObjectMonitor* monitor) { 183 Atomic::store(&_current_waiting_monitor, monitor); 184 } 185 186 // JNI handle support 187 JNIHandleBlock* active_handles() const { return _active_handles; } 188 void set_active_handles(JNIHandleBlock* block) { _active_handles = block; } 189 JNIHandleBlock* free_handle_block() const { return _free_handle_block; } 190 void set_free_handle_block(JNIHandleBlock* block) { _free_handle_block = block; } 191 192 void push_jni_handle_block(); 193 void pop_jni_handle_block(); 194 195 private: 196 MonitorChunk* _monitor_chunks; // Contains the off stack monitors 197 // allocated during deoptimization 198 // and by JNI_MonitorEnter/Exit 199 200 enum SuspendFlags { 201 // NOTE: avoid using the sign-bit as cc generates different test code 202 // when the sign-bit is used, and sometimes incorrectly - see CR 6398077 203 _trace_flag = 0x00000004U, // call tracing backend 204 _obj_deopt = 0x00000008U // suspend for object reallocation and relocking for JVMTI agent 205 }; 206 207 // various suspension related flags - atomically updated 208 volatile uint32_t _suspend_flags; 209 210 inline void set_suspend_flag(SuspendFlags f); 211 inline void clear_suspend_flag(SuspendFlags f); 212 213 public: 214 inline void set_trace_flag(); 215 inline void clear_trace_flag(); 216 inline void set_obj_deopt_flag(); 217 inline void clear_obj_deopt_flag(); 218 bool is_trace_suspend() { return (_suspend_flags & _trace_flag) != 0; } 219 bool is_obj_deopt_suspend() { return (_suspend_flags & _obj_deopt) != 0; } 220 221 // Asynchronous exception support 222 private: 223 friend class InstallAsyncExceptionHandshake; 224 friend class AsyncExceptionHandshake; 225 friend class HandshakeState; 226 227 void handle_async_exception(oop java_throwable); 228 public: 229 void install_async_exception(AsyncExceptionHandshake* aec = nullptr); 230 bool has_async_exception_condition(); 231 inline void set_pending_unsafe_access_error(); 232 static void send_async_exception(JavaThread* jt, oop java_throwable); 233 234 class NoAsyncExceptionDeliveryMark : public StackObj { 235 friend JavaThread; 236 JavaThread *_target; 237 inline NoAsyncExceptionDeliveryMark(JavaThread *t); 238 inline ~NoAsyncExceptionDeliveryMark(); 239 }; 240 241 // Safepoint support 242 public: // Expose _thread_state for SafeFetchInt() 243 volatile JavaThreadState _thread_state; 244 private: 245 SafepointMechanism::ThreadData _poll_data; 246 ThreadSafepointState* _safepoint_state; // Holds information about a thread during a safepoint 247 address _saved_exception_pc; // Saved pc of instruction where last implicit exception happened 248 NOT_PRODUCT(bool _requires_cross_modify_fence;) // State used by VerifyCrossModifyFence 249 #ifdef ASSERT 250 // Debug support for checking if code allows safepoints or not. 251 // Safepoints in the VM can happen because of allocation, invoking a VM operation, or blocking on 252 // mutex, or blocking on an object synchronizer (Java locking). 253 // If _no_safepoint_count is non-zero, then an assertion failure will happen in any of 254 // the above cases. The class NoSafepointVerifier is used to set this counter. 255 int _no_safepoint_count; // If 0, thread allow a safepoint to happen 256 257 public: 258 void inc_no_safepoint_count() { _no_safepoint_count++; } 259 void dec_no_safepoint_count() { _no_safepoint_count--; } 260 bool is_in_no_safepoint_scope() { return _no_safepoint_count > 0; } 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 bool _is_disable_suspend; // JVMTI suspend is temporarily disabled; used on current thread only 321 #ifdef ASSERT 322 bool _is_VTMS_transition_disabler; // thread currently disabled VTMS transitions 323 #endif 324 #endif 325 326 // JNI attach states: 327 enum JNIAttachStates { 328 _not_attaching_via_jni = 1, // thread is not attaching via JNI 329 _attaching_via_jni, // thread is attaching via JNI 330 _attached_via_jni // thread has attached via JNI 331 }; 332 333 // A regular JavaThread's _jni_attach_state is _not_attaching_via_jni. 334 // A native thread that is attaching via JNI starts with a value 335 // of _attaching_via_jni and transitions to _attached_via_jni. 336 volatile JNIAttachStates _jni_attach_state; 337 338 339 #if INCLUDE_JVMCI 340 // The _pending_* fields below are used to communicate extra information 341 // from an uncommon trap in JVMCI compiled code to the uncommon trap handler. 342 343 // Communicates the DeoptReason and DeoptAction of the uncommon trap 344 int _pending_deoptimization; 345 346 // Specifies whether the uncommon trap is to bci 0 of a synchronized method 347 // before the monitor has been acquired. 348 bool _pending_monitorenter; 349 350 // Specifies if the DeoptReason for the last uncommon trap was Reason_transfer_to_interpreter 351 bool _pending_transfer_to_interpreter; 352 353 // True if in a runtime call from compiled code that will deoptimize 354 // and re-execute a failed heap allocation in the interpreter. 355 bool _in_retryable_allocation; 356 357 // An id of a speculation that JVMCI compiled code can use to further describe and 358 // uniquely identify the speculative optimization guarded by an uncommon trap. 359 // See JVMCINMethodData::SPECULATION_LENGTH_BITS for further details. 360 jlong _pending_failed_speculation; 361 362 // These fields are mutually exclusive in terms of live ranges. 363 union { 364 // Communicates the pc at which the most recent implicit exception occurred 365 // from the signal handler to a deoptimization stub. 366 address _implicit_exception_pc; 367 368 // Communicates an alternative call target to an i2c stub from a JavaCall . 369 address _alternate_call_target; 370 } _jvmci; 371 372 // The JVMCIRuntime in a JVMCI shared library 373 JVMCIRuntime* _libjvmci_runtime; 374 375 // Support for high precision, thread sensitive counters in JVMCI compiled code. 376 jlong* _jvmci_counters; 377 378 // Fast thread locals for use by JVMCI 379 jlong _jvmci_reserved0; 380 jlong _jvmci_reserved1; 381 oop _jvmci_reserved_oop0; 382 383 public: 384 static jlong* _jvmci_old_thread_counters; 385 static void collect_counters(jlong* array, int length); 386 387 bool resize_counters(int current_size, int new_size); 388 389 static bool resize_all_jvmci_counters(int new_size); 390 391 void set_jvmci_reserved_oop0(oop value) { 392 _jvmci_reserved_oop0 = value; 393 } 394 395 oop get_jvmci_reserved_oop0() { 396 return _jvmci_reserved_oop0; 397 } 398 399 void set_jvmci_reserved0(jlong value) { 400 _jvmci_reserved0 = value; 401 } 402 403 jlong get_jvmci_reserved0() { 404 return _jvmci_reserved0; 405 } 406 407 void set_jvmci_reserved1(jlong value) { 408 _jvmci_reserved1 = value; 409 } 410 411 jlong get_jvmci_reserved1() { 412 return _jvmci_reserved1; 413 } 414 415 private: 416 #endif // INCLUDE_JVMCI 417 418 StackOverflow _stack_overflow_state; 419 420 void pretouch_stack(); 421 422 // Compiler exception handling (NOTE: The _exception_oop is *NOT* the same as _pending_exception. It is 423 // used to temp. parsing values into and out of the runtime system during exception handling for compiled 424 // code) 425 volatile oop _exception_oop; // Exception thrown in compiled code 426 volatile address _exception_pc; // PC where exception happened 427 volatile address _exception_handler_pc; // PC for handler of exception 428 volatile int _is_method_handle_return; // true (== 1) if the current exception PC is a MethodHandle call site. 429 430 private: 431 // support for JNI critical regions 432 jint _jni_active_critical; // count of entries into JNI critical region 433 434 // Checked JNI: function name requires exception check 435 char* _pending_jni_exception_check_fn; 436 437 // For deadlock detection. 438 int _depth_first_number; 439 440 // JVMTI PopFrame support 441 // This is set to popframe_pending to signal that top Java frame should be popped immediately 442 int _popframe_condition; 443 444 // If reallocation of scalar replaced objects fails, we throw OOM 445 // and during exception propagation, pop the top 446 // _frames_to_pop_failed_realloc frames, the ones that reference 447 // failed reallocations. 448 int _frames_to_pop_failed_realloc; 449 450 ContinuationEntry* _cont_entry; 451 intptr_t* _cont_fastpath; // the sp of the oldest known interpreted/call_stub frame inside the 452 // continuation that we know about 453 int _cont_fastpath_thread_state; // whether global thread state allows continuation fastpath (JVMTI) 454 455 // It's signed for error detection. 456 intx _held_monitor_count; // used by continuations for fast lock detection 457 intx _jni_monitor_count; 458 459 private: 460 461 friend class VMThread; 462 friend class ThreadWaitTransition; 463 friend class VM_Exit; 464 465 // Stack watermark barriers. 466 StackWatermarks _stack_watermarks; 467 468 public: 469 inline StackWatermarks* stack_watermarks() { return &_stack_watermarks; } 470 471 public: 472 // Constructor 473 JavaThread(); // delegating constructor 474 JavaThread(bool is_attaching_via_jni); // for main thread and JNI attached threads 475 JavaThread(ThreadFunction entry_point, size_t stack_size = 0); 476 ~JavaThread(); 477 478 #ifdef ASSERT 479 // verify this JavaThread hasn't be published in the Threads::list yet 480 void verify_not_published(); 481 #endif // ASSERT 482 483 StackOverflow* stack_overflow_state() { return &_stack_overflow_state; } 484 485 //JNI functiontable getter/setter for JVMTI jni function table interception API. 486 void set_jni_functions(struct JNINativeInterface_* functionTable) { 487 _jni_environment.functions = functionTable; 488 } 489 struct JNINativeInterface_* get_jni_functions() { 490 return (struct JNINativeInterface_ *)_jni_environment.functions; 491 } 492 493 // This function is called at thread creation to allow 494 // platform specific thread variables to be initialized. 495 void cache_global_variables(); 496 497 // Executes Shutdown.shutdown() 498 void invoke_shutdown_hooks(); 499 500 // Cleanup on thread exit 501 enum ExitType { 502 normal_exit, 503 jni_detach 504 }; 505 void exit(bool destroy_vm, ExitType exit_type = normal_exit); 506 507 void cleanup_failed_attach_current_thread(bool is_daemon); 508 509 // Testers 510 virtual bool is_Java_thread() const { return true; } 511 virtual bool can_call_java() const { return true; } 512 513 virtual bool is_active_Java_thread() const; 514 515 // Thread oop. threadObj() can be null for initial JavaThread 516 // (or for threads attached via JNI) 517 oop threadObj() const; 518 void set_threadOopHandles(oop p); 519 oop vthread() const; 520 void set_vthread(oop p); 521 oop scopedValueCache() const; 522 void set_scopedValueCache(oop p); 523 void clear_scopedValueBindings(); 524 oop jvmti_vthread() const; 525 void set_jvmti_vthread(oop p); 526 oop vthread_or_thread() const; 527 528 // Prepare thread and add to priority queue. If a priority is 529 // not specified, use the priority of the thread object. Threads_lock 530 // must be held while this function is called. 531 void prepare(jobject jni_thread, ThreadPriority prio=NoPriority); 532 533 void set_saved_exception_pc(address pc) { _saved_exception_pc = pc; } 534 address saved_exception_pc() { return _saved_exception_pc; } 535 536 ThreadFunction entry_point() const { return _entry_point; } 537 538 // Allocates a new Java level thread object for this thread. thread_name may be null. 539 void allocate_threadObj(Handle thread_group, const char* thread_name, bool daemon, TRAPS); 540 541 // Last frame anchor routines 542 543 JavaFrameAnchor* frame_anchor(void) { return &_anchor; } 544 545 // last_Java_sp 546 bool has_last_Java_frame() const { return _anchor.has_last_Java_frame(); } 547 intptr_t* last_Java_sp() const { return _anchor.last_Java_sp(); } 548 549 // last_Java_pc 550 551 address last_Java_pc(void) { return _anchor.last_Java_pc(); } 552 553 // Safepoint support 554 inline JavaThreadState thread_state() const; 555 inline void set_thread_state(JavaThreadState s); 556 inline void set_thread_state_fence(JavaThreadState s); // fence after setting thread state 557 inline ThreadSafepointState* safepoint_state() const; 558 inline void set_safepoint_state(ThreadSafepointState* state); 559 inline bool is_at_poll_safepoint(); 560 561 // JavaThread termination and lifecycle support: 562 void smr_delete(); 563 bool on_thread_list() const { return _on_thread_list; } 564 void set_on_thread_list() { _on_thread_list = true; } 565 566 // thread has called JavaThread::exit(), thread's GC barrier is detached 567 // or thread is terminated 568 bool is_exiting() const; 569 // thread's GC barrier is NOT detached and thread is NOT terminated 570 bool is_oop_safe() const; 571 // thread is terminated (no longer on the threads list); the thread must 572 // be protected by a ThreadsListHandle to avoid potential crashes. 573 bool check_is_terminated(TerminatedTypes l_terminated) const { 574 return l_terminated == _thread_terminated || l_terminated == _vm_exited; 575 } 576 bool is_terminated() const; 577 void set_terminated(TerminatedTypes t); 578 579 void block_if_vm_exited(); 580 581 bool doing_unsafe_access() { return _doing_unsafe_access; } 582 void set_doing_unsafe_access(bool val) { _doing_unsafe_access = val; } 583 584 bool do_not_unlock_if_synchronized() { return _do_not_unlock_if_synchronized; } 585 void set_do_not_unlock_if_synchronized(bool val) { _do_not_unlock_if_synchronized = val; } 586 587 SafepointMechanism::ThreadData* poll_data() { return &_poll_data; } 588 589 void set_requires_cross_modify_fence(bool val) PRODUCT_RETURN NOT_PRODUCT({ _requires_cross_modify_fence = val; }) 590 591 // Continuation support 592 ContinuationEntry* last_continuation() const { return _cont_entry; } 593 void set_cont_fastpath(intptr_t* x) { _cont_fastpath = x; } 594 void push_cont_fastpath(intptr_t* sp) { if (sp > _cont_fastpath) _cont_fastpath = sp; } 595 void set_cont_fastpath_thread_state(bool x) { _cont_fastpath_thread_state = (int)x; } 596 intptr_t* raw_cont_fastpath() const { return _cont_fastpath; } 597 bool cont_fastpath() const { return _cont_fastpath == nullptr && _cont_fastpath_thread_state != 0; } 598 bool cont_fastpath_thread_state() const { return _cont_fastpath_thread_state != 0; } 599 600 void inc_held_monitor_count(intx i = 1, bool jni = false); 601 void dec_held_monitor_count(intx i = 1, bool jni = false); 602 603 intx held_monitor_count() { return _held_monitor_count; } 604 intx jni_monitor_count() { return _jni_monitor_count; } 605 void clear_jni_monitor_count() { _jni_monitor_count = 0; } 606 607 inline bool is_vthread_mounted() const; 608 inline const ContinuationEntry* vthread_continuation() const; 609 610 private: 611 DEBUG_ONLY(void verify_frame_info();) 612 613 // Support for thread handshake operations 614 HandshakeState _handshake; 615 public: 616 HandshakeState* handshake_state() { return &_handshake; } 617 618 // A JavaThread can always safely operate on it self and other threads 619 // can do it safely if they are the active handshaker. 620 bool is_handshake_safe_for(Thread* th) const { 621 return _handshake.active_handshaker() == th || this == th; 622 } 623 624 // Suspend/resume support for JavaThread 625 // higher-level suspension/resume logic called by the public APIs 626 bool java_suspend(); 627 bool java_resume(); 628 bool is_suspended() { return _handshake.is_suspended(); } 629 630 // Check for async exception in addition to safepoint. 631 static void check_special_condition_for_native_trans(JavaThread *thread); 632 633 // Synchronize with another thread that is deoptimizing objects of the 634 // current thread, i.e. reverts optimizations based on escape analysis. 635 void wait_for_object_deoptimization(); 636 637 #if INCLUDE_JVMTI 638 inline void set_carrier_thread_suspended(); 639 inline void clear_carrier_thread_suspended(); 640 641 bool is_carrier_thread_suspended() const { 642 return _carrier_thread_suspended; 643 } 644 645 bool is_in_VTMS_transition() const { return _is_in_VTMS_transition; } 646 bool is_in_tmp_VTMS_transition() const { return _is_in_tmp_VTMS_transition; } 647 bool is_in_any_VTMS_transition() const { return _is_in_VTMS_transition || _is_in_tmp_VTMS_transition; } 648 649 void set_is_in_VTMS_transition(bool val); 650 void toggle_is_in_tmp_VTMS_transition() { _is_in_tmp_VTMS_transition = !_is_in_tmp_VTMS_transition; }; 651 652 bool is_disable_suspend() const { return _is_disable_suspend; } 653 void toggle_is_disable_suspend() { _is_disable_suspend = !_is_disable_suspend; }; 654 655 #ifdef ASSERT 656 bool is_VTMS_transition_disabler() const { return _is_VTMS_transition_disabler; } 657 void set_is_VTMS_transition_disabler(bool val); 658 #endif 659 #endif 660 661 // Support for object deoptimization and JFR suspension 662 void handle_special_runtime_exit_condition(); 663 bool has_special_runtime_exit_condition() { 664 return (_suspend_flags & (_obj_deopt JFR_ONLY(| _trace_flag))) != 0; 665 } 666 667 // Fast-locking support 668 bool is_lock_owned(address adr) const; 669 670 // Accessors for vframe array top 671 // The linked list of vframe arrays are sorted on sp. This means when we 672 // unpack the head must contain the vframe array to unpack. 673 void set_vframe_array_head(vframeArray* value) { _vframe_array_head = value; } 674 vframeArray* vframe_array_head() const { return _vframe_array_head; } 675 676 // Side structure for deferring update of java frame locals until deopt occurs 677 JvmtiDeferredUpdates* deferred_updates() const { return _jvmti_deferred_updates; } 678 void set_deferred_updates(JvmtiDeferredUpdates* du) { _jvmti_deferred_updates = du; } 679 680 // These only really exist to make debugging deopt problems simpler 681 682 void set_vframe_array_last(vframeArray* value) { _vframe_array_last = value; } 683 vframeArray* vframe_array_last() const { return _vframe_array_last; } 684 685 // The special resourceMark used during deoptimization 686 687 void set_deopt_mark(DeoptResourceMark* value) { _deopt_mark = value; } 688 DeoptResourceMark* deopt_mark(void) { return _deopt_mark; } 689 690 void set_deopt_compiled_method(CompiledMethod* nm) { _deopt_nmethod = nm; } 691 CompiledMethod* deopt_compiled_method() { return _deopt_nmethod; } 692 693 Method* callee_target() const { return _callee_target; } 694 void set_callee_target (Method* x) { _callee_target = x; } 695 696 // Oop results of vm runtime calls 697 oop vm_result() const { return _vm_result; } 698 void set_vm_result (oop x) { _vm_result = x; } 699 700 void set_vm_result_2 (Metadata* x) { _vm_result_2 = x; } 701 702 oop return_buffered_value() const { return _return_buffered_value; } 703 void set_return_buffered_value(oop val) { _return_buffered_value = val; } 704 705 MemRegion deferred_card_mark() const { return _deferred_card_mark; } 706 void set_deferred_card_mark(MemRegion mr) { _deferred_card_mark = mr; } 707 708 #if INCLUDE_JVMCI 709 jlong pending_failed_speculation() const { return _pending_failed_speculation; } 710 void set_pending_monitorenter(bool b) { _pending_monitorenter = b; } 711 void set_pending_deoptimization(int reason) { _pending_deoptimization = reason; } 712 void set_pending_failed_speculation(jlong failed_speculation) { _pending_failed_speculation = failed_speculation; } 713 void set_pending_transfer_to_interpreter(bool b) { _pending_transfer_to_interpreter = b; } 714 void set_jvmci_alternate_call_target(address a) { assert(_jvmci._alternate_call_target == nullptr, "must be"); _jvmci._alternate_call_target = a; } 715 void set_jvmci_implicit_exception_pc(address a) { assert(_jvmci._implicit_exception_pc == nullptr, "must be"); _jvmci._implicit_exception_pc = a; } 716 717 virtual bool in_retryable_allocation() const { return _in_retryable_allocation; } 718 void set_in_retryable_allocation(bool b) { _in_retryable_allocation = b; } 719 720 JVMCIRuntime* libjvmci_runtime() const { return _libjvmci_runtime; } 721 void set_libjvmci_runtime(JVMCIRuntime* rt) { 722 assert((_libjvmci_runtime == nullptr && rt != nullptr) || (_libjvmci_runtime != nullptr && rt == nullptr), "must be"); 723 _libjvmci_runtime = rt; 724 } 725 #endif // INCLUDE_JVMCI 726 727 // Exception handling for compiled methods 728 oop exception_oop() const; 729 address exception_pc() const { return _exception_pc; } 730 731 void set_exception_oop(oop o); 732 void set_exception_pc(address a) { _exception_pc = a; } 733 void set_exception_handler_pc(address a) { _exception_handler_pc = a; } 734 void set_is_method_handle_return(bool value) { _is_method_handle_return = value ? 1 : 0; } 735 736 void clear_exception_oop_and_pc() { 737 set_exception_oop(nullptr); 738 set_exception_pc(nullptr); 739 } 740 741 // Check if address is in the usable part of the stack (excludes protected 742 // guard pages). Can be applied to any thread and is an approximation for 743 // using is_in_live_stack when the query has to happen from another thread. 744 bool is_in_usable_stack(address adr) const { 745 return is_in_stack_range_incl(adr, _stack_overflow_state.stack_reserved_zone_base()); 746 } 747 748 // Misc. accessors/mutators 749 static ByteSize scopedValueCache_offset() { return byte_offset_of(JavaThread, _scopedValueCache); } 750 751 // For assembly stub generation 752 static ByteSize threadObj_offset() { return byte_offset_of(JavaThread, _threadObj); } 753 static ByteSize vthread_offset() { return byte_offset_of(JavaThread, _vthread); } 754 static ByteSize jni_environment_offset() { return byte_offset_of(JavaThread, _jni_environment); } 755 static ByteSize pending_jni_exception_check_fn_offset() { 756 return byte_offset_of(JavaThread, _pending_jni_exception_check_fn); 757 } 758 static ByteSize last_Java_sp_offset() { 759 return byte_offset_of(JavaThread, _anchor) + JavaFrameAnchor::last_Java_sp_offset(); 760 } 761 static ByteSize last_Java_pc_offset() { 762 return byte_offset_of(JavaThread, _anchor) + JavaFrameAnchor::last_Java_pc_offset(); 763 } 764 static ByteSize frame_anchor_offset() { 765 return byte_offset_of(JavaThread, _anchor); 766 } 767 static ByteSize callee_target_offset() { return byte_offset_of(JavaThread, _callee_target); } 768 static ByteSize vm_result_offset() { return byte_offset_of(JavaThread, _vm_result); } 769 static ByteSize vm_result_2_offset() { return byte_offset_of(JavaThread, _vm_result_2); } 770 static ByteSize return_buffered_value_offset() { return byte_offset_of(JavaThread, _return_buffered_value); } 771 static ByteSize thread_state_offset() { return byte_offset_of(JavaThread, _thread_state); } 772 static ByteSize polling_word_offset() { return byte_offset_of(JavaThread, _poll_data) + byte_offset_of(SafepointMechanism::ThreadData, _polling_word);} 773 static ByteSize polling_page_offset() { return byte_offset_of(JavaThread, _poll_data) + byte_offset_of(SafepointMechanism::ThreadData, _polling_page);} 774 static ByteSize saved_exception_pc_offset() { return byte_offset_of(JavaThread, _saved_exception_pc); } 775 static ByteSize osthread_offset() { return byte_offset_of(JavaThread, _osthread); } 776 #if INCLUDE_JVMCI 777 static ByteSize pending_deoptimization_offset() { return byte_offset_of(JavaThread, _pending_deoptimization); } 778 static ByteSize pending_monitorenter_offset() { return byte_offset_of(JavaThread, _pending_monitorenter); } 779 static ByteSize jvmci_alternate_call_target_offset() { return byte_offset_of(JavaThread, _jvmci._alternate_call_target); } 780 static ByteSize jvmci_implicit_exception_pc_offset() { return byte_offset_of(JavaThread, _jvmci._implicit_exception_pc); } 781 static ByteSize jvmci_counters_offset() { return byte_offset_of(JavaThread, _jvmci_counters); } 782 #endif // INCLUDE_JVMCI 783 static ByteSize exception_oop_offset() { return byte_offset_of(JavaThread, _exception_oop); } 784 static ByteSize exception_pc_offset() { return byte_offset_of(JavaThread, _exception_pc); } 785 static ByteSize exception_handler_pc_offset() { return byte_offset_of(JavaThread, _exception_handler_pc); } 786 static ByteSize is_method_handle_return_offset() { return byte_offset_of(JavaThread, _is_method_handle_return); } 787 788 static ByteSize active_handles_offset() { return byte_offset_of(JavaThread, _active_handles); } 789 790 // StackOverflow offsets 791 static ByteSize stack_overflow_limit_offset() { 792 return byte_offset_of(JavaThread, _stack_overflow_state._stack_overflow_limit); 793 } 794 static ByteSize stack_guard_state_offset() { 795 return byte_offset_of(JavaThread, _stack_overflow_state._stack_guard_state); 796 } 797 static ByteSize reserved_stack_activation_offset() { 798 return byte_offset_of(JavaThread, _stack_overflow_state._reserved_stack_activation); 799 } 800 static ByteSize shadow_zone_safe_limit() { 801 return byte_offset_of(JavaThread, _stack_overflow_state._shadow_zone_safe_limit); 802 } 803 static ByteSize shadow_zone_growth_watermark() { 804 return byte_offset_of(JavaThread, _stack_overflow_state._shadow_zone_growth_watermark); 805 } 806 807 static ByteSize suspend_flags_offset() { return byte_offset_of(JavaThread, _suspend_flags); } 808 809 static ByteSize do_not_unlock_if_synchronized_offset() { return byte_offset_of(JavaThread, _do_not_unlock_if_synchronized); } 810 static ByteSize should_post_on_exceptions_flag_offset() { 811 return byte_offset_of(JavaThread, _should_post_on_exceptions_flag); 812 } 813 static ByteSize doing_unsafe_access_offset() { return byte_offset_of(JavaThread, _doing_unsafe_access); } 814 NOT_PRODUCT(static ByteSize requires_cross_modify_fence_offset() { return byte_offset_of(JavaThread, _requires_cross_modify_fence); }) 815 816 static ByteSize cont_entry_offset() { return byte_offset_of(JavaThread, _cont_entry); } 817 static ByteSize cont_fastpath_offset() { return byte_offset_of(JavaThread, _cont_fastpath); } 818 static ByteSize held_monitor_count_offset() { return byte_offset_of(JavaThread, _held_monitor_count); } 819 820 #if INCLUDE_JVMTI 821 static ByteSize is_in_VTMS_transition_offset() { return byte_offset_of(JavaThread, _is_in_VTMS_transition); } 822 static ByteSize is_in_tmp_VTMS_transition_offset() { return byte_offset_of(JavaThread, _is_in_tmp_VTMS_transition); } 823 static ByteSize is_disable_suspend_offset() { return byte_offset_of(JavaThread, _is_disable_suspend); } 824 #endif 825 826 // Returns the jni environment for this thread 827 JNIEnv* jni_environment() { return &_jni_environment; } 828 829 // Returns the current thread as indicated by the given JNIEnv. 830 // We don't assert it is Thread::current here as that is done at the 831 // external JNI entry points where the JNIEnv is passed into the VM. 832 static JavaThread* thread_from_jni_environment(JNIEnv* env) { 833 JavaThread* current = reinterpret_cast<JavaThread*>(((intptr_t)env - in_bytes(jni_environment_offset()))); 834 // We can't normally get here in a thread that has completed its 835 // execution and so "is_terminated", except when the call is from 836 // AsyncGetCallTrace, which can be triggered by a signal at any point in 837 // a thread's lifecycle. A thread is also considered terminated if the VM 838 // has exited, so we have to check this and block in case this is a daemon 839 // thread returning to the VM (the JNI DirectBuffer entry points rely on 840 // this). 841 if (current->is_terminated()) { 842 current->block_if_vm_exited(); 843 } 844 return current; 845 } 846 847 // JNI critical regions. These can nest. 848 bool in_critical() { return _jni_active_critical > 0; } 849 bool in_last_critical() { return _jni_active_critical == 1; } 850 inline void enter_critical(); 851 void exit_critical() { 852 assert(Thread::current() == this, "this must be current thread"); 853 _jni_active_critical--; 854 assert(_jni_active_critical >= 0, "JNI critical nesting problem?"); 855 } 856 857 // Checked JNI: is the programmer required to check for exceptions, if so specify 858 // which function name. Returning to a Java frame should implicitly clear the 859 // pending check, this is done for Native->Java transitions (i.e. user JNI code). 860 // VM->Java transitions are not cleared, it is expected that JNI code enclosed 861 // within ThreadToNativeFromVM makes proper exception checks (i.e. VM internal). 862 bool is_pending_jni_exception_check() const { return _pending_jni_exception_check_fn != nullptr; } 863 void clear_pending_jni_exception_check() { _pending_jni_exception_check_fn = nullptr; } 864 const char* get_pending_jni_exception_check() const { return _pending_jni_exception_check_fn; } 865 void set_pending_jni_exception_check(const char* fn_name) { _pending_jni_exception_check_fn = (char*) fn_name; } 866 867 // For deadlock detection 868 int depth_first_number() { return _depth_first_number; } 869 void set_depth_first_number(int dfn) { _depth_first_number = dfn; } 870 871 private: 872 void set_monitor_chunks(MonitorChunk* monitor_chunks) { _monitor_chunks = monitor_chunks; } 873 874 public: 875 MonitorChunk* monitor_chunks() const { return _monitor_chunks; } 876 void add_monitor_chunk(MonitorChunk* chunk); 877 void remove_monitor_chunk(MonitorChunk* chunk); 878 bool in_deopt_handler() const { return _in_deopt_handler > 0; } 879 void inc_in_deopt_handler() { _in_deopt_handler++; } 880 void dec_in_deopt_handler() { 881 assert(_in_deopt_handler > 0, "mismatched deopt nesting"); 882 if (_in_deopt_handler > 0) { // robustness 883 _in_deopt_handler--; 884 } 885 } 886 887 private: 888 void set_entry_point(ThreadFunction entry_point) { _entry_point = entry_point; } 889 890 // factor out low-level mechanics for use in both normal and error cases 891 const char* get_thread_name_string(char* buf = nullptr, int buflen = 0) const; 892 893 public: 894 895 // Frame iteration; calls the function f for all frames on the stack 896 void frames_do(void f(frame*, const RegisterMap*)); 897 898 // Memory operations 899 void oops_do_frames(OopClosure* f, CodeBlobClosure* cf); 900 void oops_do_no_frames(OopClosure* f, CodeBlobClosure* cf); 901 902 // GC operations 903 virtual void nmethods_do(CodeBlobClosure* cf); 904 905 // RedefineClasses Support 906 void metadata_do(MetadataClosure* f); 907 908 // Debug method asserting thread states are correct during a handshake operation. 909 DEBUG_ONLY(void verify_states_for_handshake();) 910 911 // Misc. operations 912 const char* name() const; 913 const char* name_raw() const; 914 const char* type_name() const { return "JavaThread"; } 915 static const char* name_for(oop thread_obj); 916 917 void print_on(outputStream* st, bool print_extended_info) const; 918 void print_on(outputStream* st) const { print_on(st, false); } 919 void print() const; 920 void print_thread_state_on(outputStream*) const; 921 void print_on_error(outputStream* st, char* buf, int buflen) const; 922 void print_name_on_error(outputStream* st, char* buf, int buflen) const; 923 void verify(); 924 925 // Accessing frames 926 frame last_frame() { 927 _anchor.make_walkable(); 928 return pd_last_frame(); 929 } 930 javaVFrame* last_java_vframe(RegisterMap* reg_map) { return last_java_vframe(last_frame(), reg_map); } 931 932 frame carrier_last_frame(RegisterMap* reg_map); 933 javaVFrame* carrier_last_java_vframe(RegisterMap* reg_map) { return last_java_vframe(carrier_last_frame(reg_map), reg_map); } 934 935 frame vthread_last_frame(); 936 javaVFrame* vthread_last_java_vframe(RegisterMap* reg_map) { return last_java_vframe(vthread_last_frame(), reg_map); } 937 938 frame platform_thread_last_frame(RegisterMap* reg_map); 939 javaVFrame* platform_thread_last_java_vframe(RegisterMap* reg_map) { 940 return last_java_vframe(platform_thread_last_frame(reg_map), reg_map); 941 } 942 943 javaVFrame* last_java_vframe(const frame f, RegisterMap* reg_map); 944 945 // Returns method at 'depth' java or native frames down the stack 946 // Used for security checks 947 Klass* security_get_caller_class(int depth); 948 949 // Print stack trace in external format 950 // These variants print carrier/platform thread information only. 951 void print_stack_on(outputStream* st); 952 void print_stack() { print_stack_on(tty); } 953 // This prints the currently mounted virtual thread. 954 void print_vthread_stack_on(outputStream* st); 955 // This prints the active stack: either carrier/platform or virtual. 956 void print_active_stack_on(outputStream* st); 957 // Print current stack trace for checked JNI warnings and JNI fatal errors. 958 // This is the external format from above, but selecting the platform 959 // or vthread as applicable. 960 void print_jni_stack(); 961 962 // Print stack traces in various internal formats 963 void trace_stack() PRODUCT_RETURN; 964 void trace_stack_from(vframe* start_vf) PRODUCT_RETURN; 965 void trace_frames() PRODUCT_RETURN; 966 967 // Print an annotated view of the stack frames 968 void print_frame_layout(int depth = 0, bool validate_only = false) NOT_DEBUG_RETURN; 969 void validate_frame_layout() { 970 print_frame_layout(0, true); 971 } 972 973 // Function for testing deoptimization 974 void deoptimize(); 975 void make_zombies(); 976 977 void deoptimize_marked_methods(); 978 979 public: 980 // Returns the running thread as a JavaThread 981 static JavaThread* current() { 982 return JavaThread::cast(Thread::current()); 983 } 984 985 // Returns the current thread as a JavaThread, or nullptr if not attached 986 static inline JavaThread* current_or_null(); 987 988 // Casts 989 static JavaThread* cast(Thread* t) { 990 assert(t->is_Java_thread(), "incorrect cast to JavaThread"); 991 return static_cast<JavaThread*>(t); 992 } 993 994 static const JavaThread* cast(const Thread* t) { 995 assert(t->is_Java_thread(), "incorrect cast to const JavaThread"); 996 return static_cast<const JavaThread*>(t); 997 } 998 999 // Returns the active Java thread. Do not use this if you know you are calling 1000 // from a JavaThread, as it's slower than JavaThread::current. If called from 1001 // the VMThread, it also returns the JavaThread that instigated the VMThread's 1002 // operation. You may not want that either. 1003 static JavaThread* active(); 1004 1005 protected: 1006 virtual void pre_run(); 1007 virtual void run(); 1008 void thread_main_inner(); 1009 virtual void post_run(); 1010 1011 public: 1012 // Thread local information maintained by JVMTI. 1013 void set_jvmti_thread_state(JvmtiThreadState *value) { _jvmti_thread_state = value; } 1014 // A JvmtiThreadState is lazily allocated. This jvmti_thread_state() 1015 // getter is used to get this JavaThread's JvmtiThreadState if it has 1016 // one which means null can be returned. JvmtiThreadState::state_for() 1017 // is used to get the specified JavaThread's JvmtiThreadState if it has 1018 // one or it allocates a new JvmtiThreadState for the JavaThread and 1019 // returns it. JvmtiThreadState::state_for() will return null only if 1020 // the specified JavaThread is exiting. 1021 JvmtiThreadState *jvmti_thread_state() const { return _jvmti_thread_state; } 1022 static ByteSize jvmti_thread_state_offset() { return byte_offset_of(JavaThread, _jvmti_thread_state); } 1023 1024 #if INCLUDE_JVMTI 1025 // Rebind JVMTI thread state from carrier to virtual or from virtual to carrier. 1026 JvmtiThreadState *rebind_to_jvmti_thread_state_of(oop thread_oop); 1027 #endif 1028 1029 // JVMTI PopFrame support 1030 // Setting and clearing popframe_condition 1031 // All of these enumerated values are bits. popframe_pending 1032 // indicates that a PopFrame() has been requested and not yet been 1033 // completed. popframe_processing indicates that that PopFrame() is in 1034 // the process of being completed. popframe_force_deopt_reexecution_bit 1035 // indicates that special handling is required when returning to a 1036 // deoptimized caller. 1037 enum PopCondition { 1038 popframe_inactive = 0x00, 1039 popframe_pending_bit = 0x01, 1040 popframe_processing_bit = 0x02, 1041 popframe_force_deopt_reexecution_bit = 0x04 1042 }; 1043 PopCondition popframe_condition() { return (PopCondition) _popframe_condition; } 1044 void set_popframe_condition(PopCondition c) { _popframe_condition = c; } 1045 void set_popframe_condition_bit(PopCondition c) { _popframe_condition |= c; } 1046 void clear_popframe_condition() { _popframe_condition = popframe_inactive; } 1047 static ByteSize popframe_condition_offset() { return byte_offset_of(JavaThread, _popframe_condition); } 1048 bool has_pending_popframe() { return (popframe_condition() & popframe_pending_bit) != 0; } 1049 bool popframe_forcing_deopt_reexecution() { return (popframe_condition() & popframe_force_deopt_reexecution_bit) != 0; } 1050 1051 bool pop_frame_in_process(void) { return ((_popframe_condition & popframe_processing_bit) != 0); } 1052 void set_pop_frame_in_process(void) { _popframe_condition |= popframe_processing_bit; } 1053 void clr_pop_frame_in_process(void) { _popframe_condition &= ~popframe_processing_bit; } 1054 1055 int frames_to_pop_failed_realloc() const { return _frames_to_pop_failed_realloc; } 1056 void set_frames_to_pop_failed_realloc(int nb) { _frames_to_pop_failed_realloc = nb; } 1057 void dec_frames_to_pop_failed_realloc() { _frames_to_pop_failed_realloc--; } 1058 1059 private: 1060 // Saved incoming arguments to popped frame. 1061 // Used only when popped interpreted frame returns to deoptimized frame. 1062 void* _popframe_preserved_args; 1063 int _popframe_preserved_args_size; 1064 1065 public: 1066 void popframe_preserve_args(ByteSize size_in_bytes, void* start); 1067 void* popframe_preserved_args(); 1068 ByteSize popframe_preserved_args_size(); 1069 WordSize popframe_preserved_args_size_in_words(); 1070 void popframe_free_preserved_args(); 1071 1072 1073 private: 1074 JvmtiThreadState *_jvmti_thread_state; 1075 1076 // Used by the interpreter in fullspeed mode for frame pop, method 1077 // entry, method exit and single stepping support. This field is 1078 // only set to non-zero at a safepoint or using a direct handshake 1079 // (see EnterInterpOnlyModeClosure). 1080 // It can be set to zero asynchronously to this threads execution (i.e., without 1081 // safepoint/handshake or a lock) so we have to be very careful. 1082 // Accesses by other threads are synchronized using JvmtiThreadState_lock though. 1083 int _interp_only_mode; 1084 1085 public: 1086 // used by the interpreter for fullspeed debugging support (see above) 1087 static ByteSize interp_only_mode_offset() { return byte_offset_of(JavaThread, _interp_only_mode); } 1088 bool is_interp_only_mode() { return (_interp_only_mode != 0); } 1089 int get_interp_only_mode() { return _interp_only_mode; } 1090 int set_interp_only_mode(int val) { return _interp_only_mode = val; } 1091 void increment_interp_only_mode() { ++_interp_only_mode; } 1092 void decrement_interp_only_mode() { --_interp_only_mode; } 1093 1094 // support for cached flag that indicates whether exceptions need to be posted for this thread 1095 // if this is false, we can avoid deoptimizing when events are thrown 1096 // this gets set to reflect whether jvmtiExport::post_exception_throw would actually do anything 1097 private: 1098 int _should_post_on_exceptions_flag; 1099 1100 public: 1101 void set_should_post_on_exceptions_flag(int val) { _should_post_on_exceptions_flag = val; } 1102 1103 private: 1104 ThreadStatistics *_thread_stat; 1105 1106 public: 1107 ThreadStatistics* get_thread_stat() const { return _thread_stat; } 1108 1109 // Return a blocker object for which this thread is blocked parking. 1110 oop current_park_blocker(); 1111 1112 private: 1113 static size_t _stack_size_at_create; 1114 1115 public: 1116 static inline size_t stack_size_at_create(void) { 1117 return _stack_size_at_create; 1118 } 1119 static inline void set_stack_size_at_create(size_t value) { 1120 _stack_size_at_create = value; 1121 } 1122 1123 // Machine dependent stuff 1124 #include OS_CPU_HEADER(javaThread) 1125 1126 // JSR166 per-thread parker 1127 private: 1128 Parker _parker; 1129 public: 1130 Parker* parker() { return &_parker; } 1131 1132 public: 1133 // clearing/querying jni attach status 1134 bool is_attaching_via_jni() const { return _jni_attach_state == _attaching_via_jni; } 1135 bool has_attached_via_jni() const { return is_attaching_via_jni() || _jni_attach_state == _attached_via_jni; } 1136 inline void set_done_attaching_via_jni(); 1137 1138 // Stack dump assistance: 1139 // Track the class we want to initialize but for which we have to wait 1140 // on its init_lock() because it is already being initialized. 1141 void set_class_to_be_initialized(InstanceKlass* k); 1142 InstanceKlass* class_to_be_initialized() const; 1143 1144 private: 1145 InstanceKlass* _class_to_be_initialized; 1146 1147 // java.lang.Thread.sleep support 1148 ParkEvent * _SleepEvent; 1149 public: 1150 bool sleep(jlong millis); 1151 bool sleep_nanos(jlong nanos); 1152 1153 // java.lang.Thread interruption support 1154 void interrupt(); 1155 bool is_interrupted(bool clear_interrupted); 1156 1157 // This is only for use by JVMTI RawMonitorWait. It emulates the actions of 1158 // the Java code in Object::wait which are not present in RawMonitorWait. 1159 bool get_and_clear_interrupted(); 1160 1161 private: 1162 LockStack _lock_stack; 1163 1164 public: 1165 LockStack& lock_stack() { return _lock_stack; } 1166 1167 static ByteSize lock_stack_offset() { return byte_offset_of(JavaThread, _lock_stack); } 1168 // Those offsets are used in code generators to access the LockStack that is embedded in this 1169 // JavaThread structure. Those accesses are relative to the current thread, which 1170 // is typically in a dedicated register. 1171 static ByteSize lock_stack_top_offset() { return lock_stack_offset() + LockStack::top_offset(); } 1172 static ByteSize lock_stack_base_offset() { return lock_stack_offset() + LockStack::base_offset(); } 1173 1174 static OopStorage* thread_oop_storage(); 1175 1176 static void verify_cross_modify_fence_failure(JavaThread *thread) PRODUCT_RETURN; 1177 1178 // Helper function to create the java.lang.Thread object for a 1179 // VM-internal thread. The thread will have the given name and be 1180 // part of the System ThreadGroup. 1181 static Handle create_system_thread_object(const char* name, TRAPS); 1182 1183 // Helper function to start a VM-internal daemon thread. 1184 // E.g. ServiceThread, NotificationThread, CompilerThread etc. 1185 static void start_internal_daemon(JavaThread* current, JavaThread* target, 1186 Handle thread_oop, ThreadPriority prio); 1187 1188 // Helper function to do vm_exit_on_initialization for osthread 1189 // resource allocation failure. 1190 static void vm_exit_on_osthread_failure(JavaThread* thread); 1191 1192 // Deferred OopHandle release support 1193 private: 1194 // List of OopHandles to be released - guarded by the Service_lock. 1195 static OopHandleList* _oop_handle_list; 1196 // Add our OopHandles to the list for the service thread to release. 1197 void add_oop_handles_for_release(); 1198 // Called by the ServiceThread to release the OopHandles. 1199 static void release_oop_handles(); 1200 // Called by the ServiceThread to poll if there are any OopHandles to release. 1201 // Called when holding the Service_lock. 1202 static bool has_oop_handles_to_release() { 1203 return _oop_handle_list != nullptr; 1204 } 1205 }; 1206 1207 inline JavaThread* JavaThread::current_or_null() { 1208 Thread* current = Thread::current_or_null(); 1209 return current != nullptr ? JavaThread::cast(current) : nullptr; 1210 } 1211 1212 class UnlockFlagSaver { 1213 private: 1214 JavaThread* _thread; 1215 bool _do_not_unlock; 1216 public: 1217 UnlockFlagSaver(JavaThread* t) { 1218 _thread = t; 1219 _do_not_unlock = t->do_not_unlock_if_synchronized(); 1220 t->set_do_not_unlock_if_synchronized(false); 1221 } 1222 ~UnlockFlagSaver() { 1223 _thread->set_do_not_unlock_if_synchronized(_do_not_unlock); 1224 } 1225 }; 1226 1227 class JNIHandleMark : public StackObj { 1228 JavaThread* _thread; 1229 public: 1230 JNIHandleMark(JavaThread* thread) : _thread(thread) { 1231 thread->push_jni_handle_block(); 1232 } 1233 ~JNIHandleMark() { _thread->pop_jni_handle_block(); } 1234 }; 1235 1236 #endif // SHARE_RUNTIME_JAVATHREAD_HPP