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/threadIdentifier.hpp" 45 #include "runtime/threadStatisticalInfo.hpp" 46 #include "utilities/exceptions.hpp" 47 #include "utilities/globalDefinitions.hpp" 48 #include "utilities/macros.hpp" 49 #if INCLUDE_JFR 50 #include "jfr/support/jfrThreadExtension.hpp" 51 #endif 52 53 class AsyncExceptionHandshake; 54 class ContinuationEntry; 55 class DeoptResourceMark; 56 class JNIHandleBlock; 57 class JVMCIRuntime; 58 59 class JvmtiDeferredUpdates; 60 class JvmtiSampledObjectAllocEventCollector; 61 class JvmtiThreadState; 62 63 class Metadata; 64 class OopHandleList; 65 class OopStorage; 66 class OSThread; 67 68 class ThreadsList; 69 class ThreadSafepointState; 70 class ThreadStatistics; 71 72 class vframeArray; 73 class vframe; 74 class javaVFrame; 75 76 class JavaThread; 77 typedef void (*ThreadFunction)(JavaThread*, TRAPS); 78 79 class JavaThread: public Thread { 80 friend class VMStructs; 81 friend class JVMCIVMStructs; 82 friend class WhiteBox; 83 friend class ThreadsSMRSupport; // to access _threadObj for exiting_threads_oops_do 84 friend class HandshakeState; 85 friend class Continuation; 86 friend class Threads; 87 friend class ServiceThread; // for deferred OopHandle release access 88 private: 89 bool _on_thread_list; // Is set when this JavaThread is added to the Threads list 90 91 // All references to Java objects managed via OopHandles. These 92 // have to be released by the ServiceThread after the JavaThread has 93 // terminated - see add_oop_handles_for_release(). 94 OopHandle _threadObj; // The Java level thread object 95 OopHandle _vthread; // the value returned by Thread.currentThread(): the virtual thread, if mounted, otherwise _threadObj 96 OopHandle _jvmti_vthread; 97 OopHandle _scopedValueCache; 98 99 static OopStorage* _thread_oop_storage; 100 101 #ifdef ASSERT 102 private: 103 int _java_call_counter; 104 105 public: 106 int java_call_counter() { return _java_call_counter; } 107 void inc_java_call_counter() { _java_call_counter++; } 108 void dec_java_call_counter() { 109 assert(_java_call_counter > 0, "Invalid nesting of JavaCallWrapper"); 110 _java_call_counter--; 111 } 112 private: // restore original namespace restriction 113 #endif // ifdef ASSERT 114 115 JavaFrameAnchor _anchor; // Encapsulation of current java frame and it state 116 117 ThreadFunction _entry_point; 118 119 JNIEnv _jni_environment; 120 121 // Deopt support 122 DeoptResourceMark* _deopt_mark; // Holds special ResourceMark for deoptimization 123 124 CompiledMethod* _deopt_nmethod; // CompiledMethod that is currently being deoptimized 125 vframeArray* _vframe_array_head; // Holds the heap of the active vframeArrays 126 vframeArray* _vframe_array_last; // Holds last vFrameArray we popped 127 // Holds updates by JVMTI agents for compiled frames that cannot be performed immediately. They 128 // will be carried out as soon as possible which, in most cases, is just before deoptimization of 129 // the frame, when control returns to it. 130 JvmtiDeferredUpdates* _jvmti_deferred_updates; 131 132 // Handshake value for fixing 6243940. We need a place for the i2c 133 // adapter to store the callee Method*. This value is NEVER live 134 // across a gc point so it does NOT have to be gc'd 135 // The handshake is open ended since we can't be certain that it will 136 // be nulled. This is because we rarely ever see the race and end up 137 // in handle_wrong_method which is the backend of the handshake. See 138 // code in i2c adapters and handle_wrong_method. 139 140 Method* _callee_target; 141 142 // Used to pass back results to the interpreter or generated code running Java code. 143 oop _vm_result; // oop result is GC-preserved 144 Metadata* _vm_result_2; // non-oop result 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 // ID used as owner for inflated monitors. Same as the tidĀ field of the current 162 // _vthread object, except during creation of the primordial and JNI attached 163 // thread cases where this field can have a temporal value. 164 int64_t _lock_id; 165 166 public: 167 volatile intptr_t _Stalled; 168 bool _on_monitorenter; 169 170 bool is_on_monitorenter() { return _on_monitorenter; } 171 void set_on_monitorenter(bool val) { _on_monitorenter = val; } 172 173 void set_lock_id(int64_t tid) { 174 assert(tid >= ThreadIdentifier::initial() && tid < ThreadIdentifier::current(), "invalid tid"); 175 _lock_id = tid; 176 } 177 int64_t lock_id() const { return _lock_id; } 178 179 // For tracking the heavyweight monitor the thread is pending on. 180 ObjectMonitor* current_pending_monitor() { 181 // Use Atomic::load() to prevent data race between concurrent modification and 182 // concurrent readers, e.g. ThreadService::get_current_contended_monitor(). 183 // Especially, reloading pointer from thread after null check must be prevented. 184 return Atomic::load(&_current_pending_monitor); 185 } 186 void set_current_pending_monitor(ObjectMonitor* monitor) { 187 Atomic::store(&_current_pending_monitor, monitor); 188 } 189 void set_current_pending_monitor_is_from_java(bool from_java) { 190 _current_pending_monitor_is_from_java = from_java; 191 } 192 bool current_pending_monitor_is_from_java() { 193 return _current_pending_monitor_is_from_java; 194 } 195 ObjectMonitor* current_waiting_monitor() { 196 // See the comment in current_pending_monitor() above. 197 return Atomic::load(&_current_waiting_monitor); 198 } 199 void set_current_waiting_monitor(ObjectMonitor* monitor) { 200 Atomic::store(&_current_waiting_monitor, monitor); 201 } 202 203 // JNI handle support 204 JNIHandleBlock* active_handles() const { return _active_handles; } 205 void set_active_handles(JNIHandleBlock* block) { _active_handles = block; } 206 JNIHandleBlock* free_handle_block() const { return _free_handle_block; } 207 void set_free_handle_block(JNIHandleBlock* block) { _free_handle_block = block; } 208 209 void push_jni_handle_block(); 210 void pop_jni_handle_block(); 211 212 private: 213 MonitorChunk* _monitor_chunks; // Contains the off stack monitors 214 // allocated during deoptimization 215 // and by JNI_MonitorEnter/Exit 216 217 enum SuspendFlags { 218 // NOTE: avoid using the sign-bit as cc generates different test code 219 // when the sign-bit is used, and sometimes incorrectly - see CR 6398077 220 _trace_flag = 0x00000004U, // call tracing backend 221 _obj_deopt = 0x00000008U // suspend for object reallocation and relocking for JVMTI agent 222 }; 223 224 // various suspension related flags - atomically updated 225 volatile uint32_t _suspend_flags; 226 227 inline void set_suspend_flag(SuspendFlags f); 228 inline void clear_suspend_flag(SuspendFlags f); 229 230 public: 231 inline void set_trace_flag(); 232 inline void clear_trace_flag(); 233 inline void set_obj_deopt_flag(); 234 inline void clear_obj_deopt_flag(); 235 bool is_trace_suspend() { return (_suspend_flags & _trace_flag) != 0; } 236 bool is_obj_deopt_suspend() { return (_suspend_flags & _obj_deopt) != 0; } 237 238 // Asynchronous exception support 239 private: 240 friend class InstallAsyncExceptionHandshake; 241 friend class AsyncExceptionHandshake; 242 friend class HandshakeState; 243 244 void handle_async_exception(oop java_throwable); 245 public: 246 void install_async_exception(AsyncExceptionHandshake* aec = nullptr); 247 bool has_async_exception_condition(); 248 inline void set_pending_unsafe_access_error(); 249 static void send_async_exception(JavaThread* jt, oop java_throwable); 250 251 class NoAsyncExceptionDeliveryMark : public StackObj { 252 friend JavaThread; 253 JavaThread *_target; 254 inline NoAsyncExceptionDeliveryMark(JavaThread *t); 255 inline ~NoAsyncExceptionDeliveryMark(); 256 }; 257 258 // Safepoint support 259 public: // Expose _thread_state for SafeFetchInt() 260 volatile JavaThreadState _thread_state; 261 private: 262 SafepointMechanism::ThreadData _poll_data; 263 ThreadSafepointState* _safepoint_state; // Holds information about a thread during a safepoint 264 address _saved_exception_pc; // Saved pc of instruction where last implicit exception happened 265 NOT_PRODUCT(bool _requires_cross_modify_fence;) // State used by VerifyCrossModifyFence 266 #ifdef ASSERT 267 // Debug support for checking if code allows safepoints or not. 268 // Safepoints in the VM can happen because of allocation, invoking a VM operation, or blocking on 269 // mutex, or blocking on an object synchronizer (Java locking). 270 // If _no_safepoint_count is non-zero, then an assertion failure will happen in any of 271 // the above cases. The class NoSafepointVerifier is used to set this counter. 272 int _no_safepoint_count; // If 0, thread allow a safepoint to happen 273 274 public: 275 void inc_no_safepoint_count() { _no_safepoint_count++; } 276 void dec_no_safepoint_count() { _no_safepoint_count--; } 277 bool is_in_no_safepoint_scope() { return _no_safepoint_count > 0; } 278 #endif // ASSERT 279 public: 280 // These functions check conditions before possibly going to a safepoint. 281 // including NoSafepointVerifier. 282 void check_for_valid_safepoint_state() NOT_DEBUG_RETURN; 283 void check_possible_safepoint() NOT_DEBUG_RETURN; 284 285 #ifdef ASSERT 286 private: 287 volatile uint64_t _visited_for_critical_count; 288 289 public: 290 void set_visited_for_critical_count(uint64_t safepoint_id) { 291 assert(_visited_for_critical_count == 0, "Must be reset before set"); 292 assert((safepoint_id & 0x1) == 1, "Must be odd"); 293 _visited_for_critical_count = safepoint_id; 294 } 295 void reset_visited_for_critical_count(uint64_t safepoint_id) { 296 assert(_visited_for_critical_count == safepoint_id, "Was not visited"); 297 _visited_for_critical_count = 0; 298 } 299 bool was_visited_for_critical_count(uint64_t safepoint_id) const { 300 return _visited_for_critical_count == safepoint_id; 301 } 302 #endif // ASSERT 303 304 // JavaThread termination support 305 public: 306 enum TerminatedTypes { 307 _not_terminated = 0xDEAD - 3, 308 _thread_exiting, // JavaThread::exit() has been called for this thread 309 _thread_gc_barrier_detached, // thread's GC barrier has been detached 310 _thread_terminated, // JavaThread is removed from thread list 311 _vm_exited // JavaThread is still executing native code, but VM is terminated 312 // only VM_Exit can set _vm_exited 313 }; 314 315 private: 316 // In general a JavaThread's _terminated field transitions as follows: 317 // 318 // _not_terminated => _thread_exiting => _thread_gc_barrier_detached => _thread_terminated 319 // 320 // _vm_exited is a special value to cover the case of a JavaThread 321 // executing native code after the VM itself is terminated. 322 // 323 // A JavaThread that fails to JNI attach has these _terminated field transitions: 324 // _not_terminated => _thread_terminated 325 // 326 volatile TerminatedTypes _terminated; 327 328 jint _in_deopt_handler; // count of deoptimization 329 // handlers thread is in 330 volatile bool _doing_unsafe_access; // Thread may fault due to unsafe access 331 bool _do_not_unlock_if_synchronized; // Do not unlock the receiver of a synchronized method (since it was 332 // never locked) when throwing an exception. Used by interpreter only. 333 #if INCLUDE_JVMTI 334 volatile bool _carrier_thread_suspended; // Carrier thread is externally suspended 335 bool _is_in_VTMS_transition; // thread is in virtual thread mount state transition 336 bool _is_in_tmp_VTMS_transition; // thread is in temporary virtual thread mount state transition 337 bool _is_disable_suspend; // JVMTI suspend is temporarily disabled; used on current thread only 338 #ifdef ASSERT 339 bool _is_VTMS_transition_disabler; // thread currently disabled VTMS transitions 340 #endif 341 #endif 342 343 // JNI attach states: 344 enum JNIAttachStates { 345 _not_attaching_via_jni = 1, // thread is not attaching via JNI 346 _attaching_via_jni, // thread is attaching via JNI 347 _attached_via_jni // thread has attached via JNI 348 }; 349 350 // A regular JavaThread's _jni_attach_state is _not_attaching_via_jni. 351 // A native thread that is attaching via JNI starts with a value 352 // of _attaching_via_jni and transitions to _attached_via_jni. 353 volatile JNIAttachStates _jni_attach_state; 354 355 356 #if INCLUDE_JVMCI 357 // The _pending_* fields below are used to communicate extra information 358 // from an uncommon trap in JVMCI compiled code to the uncommon trap handler. 359 360 // Communicates the DeoptReason and DeoptAction of the uncommon trap 361 int _pending_deoptimization; 362 363 // Specifies whether the uncommon trap is to bci 0 of a synchronized method 364 // before the monitor has been acquired. 365 bool _pending_monitorenter; 366 367 // Specifies if the DeoptReason for the last uncommon trap was Reason_transfer_to_interpreter 368 bool _pending_transfer_to_interpreter; 369 370 // True if in a runtime call from compiled code that will deoptimize 371 // and re-execute a failed heap allocation in the interpreter. 372 bool _in_retryable_allocation; 373 374 // An id of a speculation that JVMCI compiled code can use to further describe and 375 // uniquely identify the speculative optimization guarded by an uncommon trap. 376 // See JVMCINMethodData::SPECULATION_LENGTH_BITS for further details. 377 jlong _pending_failed_speculation; 378 379 // These fields are mutually exclusive in terms of live ranges. 380 union { 381 // Communicates the pc at which the most recent implicit exception occurred 382 // from the signal handler to a deoptimization stub. 383 address _implicit_exception_pc; 384 385 // Communicates an alternative call target to an i2c stub from a JavaCall . 386 address _alternate_call_target; 387 } _jvmci; 388 389 // The JVMCIRuntime in a JVMCI shared library 390 JVMCIRuntime* _libjvmci_runtime; 391 392 // Support for high precision, thread sensitive counters in JVMCI compiled code. 393 jlong* _jvmci_counters; 394 395 // Fast thread locals for use by JVMCI 396 jlong _jvmci_reserved0; 397 jlong _jvmci_reserved1; 398 oop _jvmci_reserved_oop0; 399 400 public: 401 static jlong* _jvmci_old_thread_counters; 402 static void collect_counters(jlong* array, int length); 403 404 bool resize_counters(int current_size, int new_size); 405 406 static bool resize_all_jvmci_counters(int new_size); 407 408 void set_jvmci_reserved_oop0(oop value) { 409 _jvmci_reserved_oop0 = value; 410 } 411 412 oop get_jvmci_reserved_oop0() { 413 return _jvmci_reserved_oop0; 414 } 415 416 void set_jvmci_reserved0(jlong value) { 417 _jvmci_reserved0 = value; 418 } 419 420 jlong get_jvmci_reserved0() { 421 return _jvmci_reserved0; 422 } 423 424 void set_jvmci_reserved1(jlong value) { 425 _jvmci_reserved1 = value; 426 } 427 428 jlong get_jvmci_reserved1() { 429 return _jvmci_reserved1; 430 } 431 432 private: 433 #endif // INCLUDE_JVMCI 434 435 StackOverflow _stack_overflow_state; 436 437 void pretouch_stack(); 438 439 // Compiler exception handling (NOTE: The _exception_oop is *NOT* the same as _pending_exception. It is 440 // used to temp. parsing values into and out of the runtime system during exception handling for compiled 441 // code) 442 volatile oop _exception_oop; // Exception thrown in compiled code 443 volatile address _exception_pc; // PC where exception happened 444 volatile address _exception_handler_pc; // PC for handler of exception 445 volatile int _is_method_handle_return; // true (== 1) if the current exception PC is a MethodHandle call site. 446 447 private: 448 // support for JNI critical regions 449 jint _jni_active_critical; // count of entries into JNI critical region 450 451 // Checked JNI: function name requires exception check 452 char* _pending_jni_exception_check_fn; 453 454 // For deadlock detection. 455 int _depth_first_number; 456 457 // JVMTI PopFrame support 458 // This is set to popframe_pending to signal that top Java frame should be popped immediately 459 int _popframe_condition; 460 461 // If reallocation of scalar replaced objects fails, we throw OOM 462 // and during exception propagation, pop the top 463 // _frames_to_pop_failed_realloc frames, the ones that reference 464 // failed reallocations. 465 int _frames_to_pop_failed_realloc; 466 467 ContinuationEntry* _cont_entry; 468 intptr_t* _cont_fastpath; // the sp of the oldest known interpreted/call_stub frame inside the 469 // continuation that we know about 470 int _cont_fastpath_thread_state; // whether global thread state allows continuation fastpath (JVMTI) 471 472 // It's signed for error detection. 473 intx _held_monitor_count; // used by continuations for fast lock detection 474 intx _jni_monitor_count; 475 bool _preempting; 476 bool _preemption_cancelled; 477 bool _jvmti_unmount_event_pending; 478 address _preempt_alternate_return; // used when preempting a thread 479 address _preempt_alternate_return_sp; 480 481 #ifdef ASSERT 482 intx _obj_locker_count; 483 484 public: 485 intx obj_locker_count() { return _obj_locker_count; } 486 void inc_obj_locker_count() { 487 assert(_obj_locker_count >= 0, "Must always be greater than 0: " INTX_FORMAT, _obj_locker_count); 488 _obj_locker_count++; 489 } 490 void dec_obj_locker_count() { 491 _obj_locker_count--; 492 assert(_obj_locker_count >= 0, "Must always be greater than 0: " INTX_FORMAT, _obj_locker_count); 493 } 494 #endif // ASSERT 495 496 private: 497 498 friend class VMThread; 499 friend class ThreadWaitTransition; 500 friend class VM_Exit; 501 502 // Stack watermark barriers. 503 StackWatermarks _stack_watermarks; 504 505 public: 506 inline StackWatermarks* stack_watermarks() { return &_stack_watermarks; } 507 508 public: 509 // Constructor 510 JavaThread(); // delegating constructor 511 JavaThread(bool is_attaching_via_jni); // for main thread and JNI attached threads 512 JavaThread(ThreadFunction entry_point, size_t stack_size = 0); 513 ~JavaThread(); 514 515 #ifdef ASSERT 516 // verify this JavaThread hasn't be published in the Threads::list yet 517 void verify_not_published(); 518 #endif // ASSERT 519 520 StackOverflow* stack_overflow_state() { return &_stack_overflow_state; } 521 522 //JNI functiontable getter/setter for JVMTI jni function table interception API. 523 void set_jni_functions(struct JNINativeInterface_* functionTable) { 524 _jni_environment.functions = functionTable; 525 } 526 struct JNINativeInterface_* get_jni_functions() { 527 return (struct JNINativeInterface_ *)_jni_environment.functions; 528 } 529 530 // This function is called at thread creation to allow 531 // platform specific thread variables to be initialized. 532 void cache_global_variables(); 533 534 // Executes Shutdown.shutdown() 535 void invoke_shutdown_hooks(); 536 537 // Cleanup on thread exit 538 enum ExitType { 539 normal_exit, 540 jni_detach 541 }; 542 void exit(bool destroy_vm, ExitType exit_type = normal_exit); 543 544 void cleanup_failed_attach_current_thread(bool is_daemon); 545 546 // Testers 547 virtual bool is_Java_thread() const { return true; } 548 virtual bool can_call_java() const { return true; } 549 550 virtual bool is_active_Java_thread() const; 551 552 // Thread oop. threadObj() can be null for initial JavaThread 553 // (or for threads attached via JNI) 554 oop threadObj() const; 555 void set_threadOopHandles(oop p); 556 oop vthread() const; 557 void set_vthread(oop p); 558 oop scopedValueCache() const; 559 void set_scopedValueCache(oop p); 560 void clear_scopedValueBindings(); 561 oop jvmti_vthread() const; 562 void set_jvmti_vthread(oop p); 563 oop vthread_or_thread() const; 564 565 // Prepare thread and add to priority queue. If a priority is 566 // not specified, use the priority of the thread object. Threads_lock 567 // must be held while this function is called. 568 void prepare(jobject jni_thread, ThreadPriority prio=NoPriority); 569 570 void set_saved_exception_pc(address pc) { _saved_exception_pc = pc; } 571 address saved_exception_pc() { return _saved_exception_pc; } 572 573 ThreadFunction entry_point() const { return _entry_point; } 574 575 // Allocates a new Java level thread object for this thread. thread_name may be null. 576 void allocate_threadObj(Handle thread_group, const char* thread_name, bool daemon, TRAPS); 577 578 // Last frame anchor routines 579 580 JavaFrameAnchor* frame_anchor(void) { return &_anchor; } 581 582 // last_Java_sp 583 bool has_last_Java_frame() const { return _anchor.has_last_Java_frame(); } 584 intptr_t* last_Java_sp() const { return _anchor.last_Java_sp(); } 585 586 // last_Java_pc 587 588 address last_Java_pc(void) { return _anchor.last_Java_pc(); } 589 590 // Safepoint support 591 inline JavaThreadState thread_state() const; 592 inline void set_thread_state(JavaThreadState s); 593 inline void set_thread_state_fence(JavaThreadState s); // fence after setting thread state 594 inline ThreadSafepointState* safepoint_state() const; 595 inline void set_safepoint_state(ThreadSafepointState* state); 596 inline bool is_at_poll_safepoint(); 597 598 // JavaThread termination and lifecycle support: 599 void smr_delete(); 600 bool on_thread_list() const { return _on_thread_list; } 601 void set_on_thread_list() { _on_thread_list = true; } 602 603 // thread has called JavaThread::exit(), thread's GC barrier is detached 604 // or thread is terminated 605 bool is_exiting() const; 606 // thread's GC barrier is NOT detached and thread is NOT terminated 607 bool is_oop_safe() const; 608 // thread is terminated (no longer on the threads list); the thread must 609 // be protected by a ThreadsListHandle to avoid potential crashes. 610 bool check_is_terminated(TerminatedTypes l_terminated) const { 611 return l_terminated == _thread_terminated || l_terminated == _vm_exited; 612 } 613 bool is_terminated() const; 614 void set_terminated(TerminatedTypes t); 615 616 void block_if_vm_exited(); 617 618 bool doing_unsafe_access() { return _doing_unsafe_access; } 619 void set_doing_unsafe_access(bool val) { _doing_unsafe_access = val; } 620 621 bool do_not_unlock_if_synchronized() { return _do_not_unlock_if_synchronized; } 622 void set_do_not_unlock_if_synchronized(bool val) { _do_not_unlock_if_synchronized = val; } 623 624 SafepointMechanism::ThreadData* poll_data() { return &_poll_data; } 625 626 void set_requires_cross_modify_fence(bool val) PRODUCT_RETURN NOT_PRODUCT({ _requires_cross_modify_fence = val; }) 627 628 // Continuation support 629 ContinuationEntry* last_continuation() const { return _cont_entry; } 630 void set_cont_fastpath(intptr_t* x) { _cont_fastpath = x; } 631 void push_cont_fastpath(intptr_t* sp) { if (sp > _cont_fastpath) _cont_fastpath = sp; } 632 void set_cont_fastpath_thread_state(bool x) { _cont_fastpath_thread_state = (int)x; } 633 intptr_t* raw_cont_fastpath() const { return _cont_fastpath; } 634 bool cont_fastpath() const { return _cont_fastpath == nullptr && _cont_fastpath_thread_state != 0; } 635 bool cont_fastpath_thread_state() const { return _cont_fastpath_thread_state != 0; } 636 637 void inc_held_monitor_count(intx i = 1, bool jni = false); 638 void dec_held_monitor_count(intx i = 1, bool jni = false); 639 intx held_monitor_count() { return _held_monitor_count; } 640 641 intx jni_monitor_count() { return _jni_monitor_count; } 642 void clear_jni_monitor_count() { _jni_monitor_count = 0; } 643 644 inline bool is_vthread_mounted() const; 645 inline const ContinuationEntry* vthread_continuation() const; 646 647 bool preempting() { return _preempting; } 648 void set_preempting(bool b) { _preempting = b; } 649 650 bool preemption_cancelled() { return _preemption_cancelled; } 651 void set_preemption_cancelled(bool val) { _preemption_cancelled = val; } 652 653 bool jvmti_unmount_event_pending() { return _jvmti_unmount_event_pending; } 654 void set_jvmti_unmount_event_pending(bool val) { _jvmti_unmount_event_pending = val; } 655 656 void set_preempt_alternate_return(address val) { _preempt_alternate_return = val; } 657 void set_preempt_alternate_return_sp(address val) { _preempt_alternate_return_sp = val; } 658 private: 659 DEBUG_ONLY(void verify_frame_info();) 660 661 // Support for thread handshake operations 662 HandshakeState _handshake; 663 public: 664 HandshakeState* handshake_state() { return &_handshake; } 665 666 // A JavaThread can always safely operate on it self and other threads 667 // can do it safely if they are the active handshaker. 668 bool is_handshake_safe_for(Thread* th) const { 669 return _handshake.active_handshaker() == th || this == th; 670 } 671 672 // Suspend/resume support for JavaThread 673 // higher-level suspension/resume logic called by the public APIs 674 bool java_suspend(); 675 bool java_resume(); 676 bool is_suspended() { return _handshake.is_suspended(); } 677 678 // Check for async exception in addition to safepoint. 679 static void check_special_condition_for_native_trans(JavaThread *thread); 680 681 // Synchronize with another thread that is deoptimizing objects of the 682 // current thread, i.e. reverts optimizations based on escape analysis. 683 void wait_for_object_deoptimization(); 684 685 #if INCLUDE_JVMTI 686 inline void set_carrier_thread_suspended(); 687 inline void clear_carrier_thread_suspended(); 688 689 bool is_carrier_thread_suspended() const { 690 return _carrier_thread_suspended; 691 } 692 693 bool is_in_VTMS_transition() const { return _is_in_VTMS_transition; } 694 bool is_in_tmp_VTMS_transition() const { return _is_in_tmp_VTMS_transition; } 695 bool is_in_any_VTMS_transition() const { return _is_in_VTMS_transition || _is_in_tmp_VTMS_transition; } 696 697 void set_is_in_VTMS_transition(bool val); 698 void toggle_is_in_tmp_VTMS_transition() { _is_in_tmp_VTMS_transition = !_is_in_tmp_VTMS_transition; }; 699 700 bool is_disable_suspend() const { return _is_disable_suspend; } 701 void toggle_is_disable_suspend() { _is_disable_suspend = !_is_disable_suspend; }; 702 703 #ifdef ASSERT 704 bool is_VTMS_transition_disabler() const { return _is_VTMS_transition_disabler; } 705 void set_is_VTMS_transition_disabler(bool val); 706 #endif 707 #endif 708 709 // Support for object deoptimization and JFR suspension 710 void handle_special_runtime_exit_condition(); 711 bool has_special_runtime_exit_condition() { 712 return (_suspend_flags & (_obj_deopt JFR_ONLY(| _trace_flag))) != 0; 713 } 714 715 // Fast-locking support 716 bool is_lock_owned(address adr) const; 717 718 // Accessors for vframe array top 719 // The linked list of vframe arrays are sorted on sp. This means when we 720 // unpack the head must contain the vframe array to unpack. 721 void set_vframe_array_head(vframeArray* value) { _vframe_array_head = value; } 722 vframeArray* vframe_array_head() const { return _vframe_array_head; } 723 724 // Side structure for deferring update of java frame locals until deopt occurs 725 JvmtiDeferredUpdates* deferred_updates() const { return _jvmti_deferred_updates; } 726 void set_deferred_updates(JvmtiDeferredUpdates* du) { _jvmti_deferred_updates = du; } 727 728 // These only really exist to make debugging deopt problems simpler 729 730 void set_vframe_array_last(vframeArray* value) { _vframe_array_last = value; } 731 vframeArray* vframe_array_last() const { return _vframe_array_last; } 732 733 // The special resourceMark used during deoptimization 734 735 void set_deopt_mark(DeoptResourceMark* value) { _deopt_mark = value; } 736 DeoptResourceMark* deopt_mark(void) { return _deopt_mark; } 737 738 void set_deopt_compiled_method(CompiledMethod* nm) { _deopt_nmethod = nm; } 739 CompiledMethod* deopt_compiled_method() { return _deopt_nmethod; } 740 741 Method* callee_target() const { return _callee_target; } 742 void set_callee_target (Method* x) { _callee_target = x; } 743 744 // Oop results of vm runtime calls 745 oop vm_result() const { return _vm_result; } 746 void set_vm_result (oop x) { _vm_result = x; } 747 748 void set_vm_result_2 (Metadata* x) { _vm_result_2 = x; } 749 750 MemRegion deferred_card_mark() const { return _deferred_card_mark; } 751 void set_deferred_card_mark(MemRegion mr) { _deferred_card_mark = mr; } 752 753 #if INCLUDE_JVMCI 754 jlong pending_failed_speculation() const { return _pending_failed_speculation; } 755 void set_pending_monitorenter(bool b) { _pending_monitorenter = b; } 756 void set_pending_deoptimization(int reason) { _pending_deoptimization = reason; } 757 void set_pending_failed_speculation(jlong failed_speculation) { _pending_failed_speculation = failed_speculation; } 758 void set_pending_transfer_to_interpreter(bool b) { _pending_transfer_to_interpreter = b; } 759 void set_jvmci_alternate_call_target(address a) { assert(_jvmci._alternate_call_target == nullptr, "must be"); _jvmci._alternate_call_target = a; } 760 void set_jvmci_implicit_exception_pc(address a) { assert(_jvmci._implicit_exception_pc == nullptr, "must be"); _jvmci._implicit_exception_pc = a; } 761 762 virtual bool in_retryable_allocation() const { return _in_retryable_allocation; } 763 void set_in_retryable_allocation(bool b) { _in_retryable_allocation = b; } 764 765 JVMCIRuntime* libjvmci_runtime() const { return _libjvmci_runtime; } 766 void set_libjvmci_runtime(JVMCIRuntime* rt) { 767 assert((_libjvmci_runtime == nullptr && rt != nullptr) || (_libjvmci_runtime != nullptr && rt == nullptr), "must be"); 768 _libjvmci_runtime = rt; 769 } 770 #endif // INCLUDE_JVMCI 771 772 // Exception handling for compiled methods 773 oop exception_oop() const; 774 address exception_pc() const { return _exception_pc; } 775 776 void set_exception_oop(oop o); 777 void set_exception_pc(address a) { _exception_pc = a; } 778 void set_exception_handler_pc(address a) { _exception_handler_pc = a; } 779 void set_is_method_handle_return(bool value) { _is_method_handle_return = value ? 1 : 0; } 780 781 void clear_exception_oop_and_pc() { 782 set_exception_oop(nullptr); 783 set_exception_pc(nullptr); 784 } 785 786 // Check if address is in the usable part of the stack (excludes protected 787 // guard pages). Can be applied to any thread and is an approximation for 788 // using is_in_live_stack when the query has to happen from another thread. 789 bool is_in_usable_stack(address adr) const { 790 return is_in_stack_range_incl(adr, _stack_overflow_state.stack_reserved_zone_base()); 791 } 792 793 // Misc. accessors/mutators 794 static ByteSize scopedValueCache_offset() { return byte_offset_of(JavaThread, _scopedValueCache); } 795 796 // For assembly stub generation 797 static ByteSize threadObj_offset() { return byte_offset_of(JavaThread, _threadObj); } 798 static ByteSize vthread_offset() { return byte_offset_of(JavaThread, _vthread); } 799 static ByteSize jni_environment_offset() { return byte_offset_of(JavaThread, _jni_environment); } 800 static ByteSize pending_jni_exception_check_fn_offset() { 801 return byte_offset_of(JavaThread, _pending_jni_exception_check_fn); 802 } 803 static ByteSize last_Java_sp_offset() { 804 return byte_offset_of(JavaThread, _anchor) + JavaFrameAnchor::last_Java_sp_offset(); 805 } 806 static ByteSize last_Java_pc_offset() { 807 return byte_offset_of(JavaThread, _anchor) + JavaFrameAnchor::last_Java_pc_offset(); 808 } 809 static ByteSize frame_anchor_offset() { 810 return byte_offset_of(JavaThread, _anchor); 811 } 812 static ByteSize callee_target_offset() { return byte_offset_of(JavaThread, _callee_target); } 813 static ByteSize vm_result_offset() { return byte_offset_of(JavaThread, _vm_result); } 814 static ByteSize vm_result_2_offset() { return byte_offset_of(JavaThread, _vm_result_2); } 815 static ByteSize thread_state_offset() { return byte_offset_of(JavaThread, _thread_state); } 816 static ByteSize polling_word_offset() { return byte_offset_of(JavaThread, _poll_data) + byte_offset_of(SafepointMechanism::ThreadData, _polling_word);} 817 static ByteSize polling_page_offset() { return byte_offset_of(JavaThread, _poll_data) + byte_offset_of(SafepointMechanism::ThreadData, _polling_page);} 818 static ByteSize saved_exception_pc_offset() { return byte_offset_of(JavaThread, _saved_exception_pc); } 819 static ByteSize osthread_offset() { return byte_offset_of(JavaThread, _osthread); } 820 #if INCLUDE_JVMCI 821 static ByteSize pending_deoptimization_offset() { return byte_offset_of(JavaThread, _pending_deoptimization); } 822 static ByteSize pending_monitorenter_offset() { return byte_offset_of(JavaThread, _pending_monitorenter); } 823 static ByteSize jvmci_alternate_call_target_offset() { return byte_offset_of(JavaThread, _jvmci._alternate_call_target); } 824 static ByteSize jvmci_implicit_exception_pc_offset() { return byte_offset_of(JavaThread, _jvmci._implicit_exception_pc); } 825 static ByteSize jvmci_counters_offset() { return byte_offset_of(JavaThread, _jvmci_counters); } 826 #endif // INCLUDE_JVMCI 827 static ByteSize exception_oop_offset() { return byte_offset_of(JavaThread, _exception_oop); } 828 static ByteSize exception_pc_offset() { return byte_offset_of(JavaThread, _exception_pc); } 829 static ByteSize exception_handler_pc_offset() { return byte_offset_of(JavaThread, _exception_handler_pc); } 830 static ByteSize is_method_handle_return_offset() { return byte_offset_of(JavaThread, _is_method_handle_return); } 831 832 static ByteSize active_handles_offset() { return byte_offset_of(JavaThread, _active_handles); } 833 834 // StackOverflow offsets 835 static ByteSize stack_overflow_limit_offset() { 836 return byte_offset_of(JavaThread, _stack_overflow_state._stack_overflow_limit); 837 } 838 static ByteSize stack_guard_state_offset() { 839 return byte_offset_of(JavaThread, _stack_overflow_state._stack_guard_state); 840 } 841 static ByteSize reserved_stack_activation_offset() { 842 return byte_offset_of(JavaThread, _stack_overflow_state._reserved_stack_activation); 843 } 844 static ByteSize shadow_zone_safe_limit() { 845 return byte_offset_of(JavaThread, _stack_overflow_state._shadow_zone_safe_limit); 846 } 847 static ByteSize shadow_zone_growth_watermark() { 848 return byte_offset_of(JavaThread, _stack_overflow_state._shadow_zone_growth_watermark); 849 } 850 851 static ByteSize suspend_flags_offset() { return byte_offset_of(JavaThread, _suspend_flags); } 852 853 static ByteSize do_not_unlock_if_synchronized_offset() { return byte_offset_of(JavaThread, _do_not_unlock_if_synchronized); } 854 static ByteSize should_post_on_exceptions_flag_offset() { 855 return byte_offset_of(JavaThread, _should_post_on_exceptions_flag); 856 } 857 static ByteSize doing_unsafe_access_offset() { return byte_offset_of(JavaThread, _doing_unsafe_access); } 858 NOT_PRODUCT(static ByteSize requires_cross_modify_fence_offset() { return byte_offset_of(JavaThread, _requires_cross_modify_fence); }) 859 860 static ByteSize lock_id_offset() { return byte_offset_of(JavaThread, _lock_id); } 861 862 static ByteSize cont_entry_offset() { return byte_offset_of(JavaThread, _cont_entry); } 863 static ByteSize cont_fastpath_offset() { return byte_offset_of(JavaThread, _cont_fastpath); } 864 static ByteSize held_monitor_count_offset() { return byte_offset_of(JavaThread, _held_monitor_count); } 865 static ByteSize preempting_offset() { return byte_offset_of(JavaThread, _preempting); } 866 static ByteSize preemption_cancelled_offset() { return byte_offset_of(JavaThread, _preemption_cancelled); } 867 static ByteSize preempt_alternate_return_offset() { 868 return byte_offset_of(JavaThread, _preempt_alternate_return); 869 } 870 871 #if INCLUDE_JVMTI 872 static ByteSize is_in_VTMS_transition_offset() { return byte_offset_of(JavaThread, _is_in_VTMS_transition); } 873 static ByteSize is_in_tmp_VTMS_transition_offset() { return byte_offset_of(JavaThread, _is_in_tmp_VTMS_transition); } 874 static ByteSize is_disable_suspend_offset() { return byte_offset_of(JavaThread, _is_disable_suspend); } 875 #endif 876 877 // Returns the jni environment for this thread 878 JNIEnv* jni_environment() { return &_jni_environment; } 879 880 // Returns the current thread as indicated by the given JNIEnv. 881 // We don't assert it is Thread::current here as that is done at the 882 // external JNI entry points where the JNIEnv is passed into the VM. 883 static JavaThread* thread_from_jni_environment(JNIEnv* env) { 884 JavaThread* current = reinterpret_cast<JavaThread*>(((intptr_t)env - in_bytes(jni_environment_offset()))); 885 // We can't normally get here in a thread that has completed its 886 // execution and so "is_terminated", except when the call is from 887 // AsyncGetCallTrace, which can be triggered by a signal at any point in 888 // a thread's lifecycle. A thread is also considered terminated if the VM 889 // has exited, so we have to check this and block in case this is a daemon 890 // thread returning to the VM (the JNI DirectBuffer entry points rely on 891 // this). 892 if (current->is_terminated()) { 893 current->block_if_vm_exited(); 894 } 895 return current; 896 } 897 898 // JNI critical regions. These can nest. 899 bool in_critical() { return _jni_active_critical > 0; } 900 bool in_last_critical() { return _jni_active_critical == 1; } 901 inline void enter_critical(); 902 void exit_critical() { 903 assert(Thread::current() == this, "this must be current thread"); 904 _jni_active_critical--; 905 assert(_jni_active_critical >= 0, "JNI critical nesting problem?"); 906 } 907 908 // Checked JNI: is the programmer required to check for exceptions, if so specify 909 // which function name. Returning to a Java frame should implicitly clear the 910 // pending check, this is done for Native->Java transitions (i.e. user JNI code). 911 // VM->Java transitions are not cleared, it is expected that JNI code enclosed 912 // within ThreadToNativeFromVM makes proper exception checks (i.e. VM internal). 913 bool is_pending_jni_exception_check() const { return _pending_jni_exception_check_fn != nullptr; } 914 void clear_pending_jni_exception_check() { _pending_jni_exception_check_fn = nullptr; } 915 const char* get_pending_jni_exception_check() const { return _pending_jni_exception_check_fn; } 916 void set_pending_jni_exception_check(const char* fn_name) { _pending_jni_exception_check_fn = (char*) fn_name; } 917 918 // For deadlock detection 919 int depth_first_number() { return _depth_first_number; } 920 void set_depth_first_number(int dfn) { _depth_first_number = dfn; } 921 922 private: 923 void set_monitor_chunks(MonitorChunk* monitor_chunks) { _monitor_chunks = monitor_chunks; } 924 925 public: 926 MonitorChunk* monitor_chunks() const { return _monitor_chunks; } 927 void add_monitor_chunk(MonitorChunk* chunk); 928 void remove_monitor_chunk(MonitorChunk* chunk); 929 bool in_deopt_handler() const { return _in_deopt_handler > 0; } 930 void inc_in_deopt_handler() { _in_deopt_handler++; } 931 void dec_in_deopt_handler() { 932 assert(_in_deopt_handler > 0, "mismatched deopt nesting"); 933 if (_in_deopt_handler > 0) { // robustness 934 _in_deopt_handler--; 935 } 936 } 937 938 private: 939 void set_entry_point(ThreadFunction entry_point) { _entry_point = entry_point; } 940 941 // factor out low-level mechanics for use in both normal and error cases 942 const char* get_thread_name_string(char* buf = nullptr, int buflen = 0) const; 943 944 public: 945 946 // Frame iteration; calls the function f for all frames on the stack 947 void frames_do(void f(frame*, const RegisterMap*)); 948 949 // Memory operations 950 void oops_do_frames(OopClosure* f, CodeBlobClosure* cf); 951 void oops_do_no_frames(OopClosure* f, CodeBlobClosure* cf); 952 953 // GC operations 954 virtual void nmethods_do(CodeBlobClosure* cf); 955 956 // RedefineClasses Support 957 void metadata_do(MetadataClosure* f); 958 959 // Debug method asserting thread states are correct during a handshake operation. 960 DEBUG_ONLY(void verify_states_for_handshake();) 961 962 // Misc. operations 963 const char* name() const; 964 const char* name_raw() const; 965 const char* type_name() const { return "JavaThread"; } 966 static const char* name_for(oop thread_obj); 967 968 void print_on(outputStream* st, bool print_extended_info) const; 969 void print_on(outputStream* st) const { print_on(st, false); } 970 void print() const; 971 void print_thread_state_on(outputStream*) const; 972 void print_on_error(outputStream* st, char* buf, int buflen) const; 973 void print_name_on_error(outputStream* st, char* buf, int buflen) const; 974 void verify(); 975 976 // Accessing frames 977 frame last_frame() { 978 _anchor.make_walkable(); 979 return pd_last_frame(); 980 } 981 javaVFrame* last_java_vframe(RegisterMap* reg_map) { return last_java_vframe(last_frame(), reg_map); } 982 983 frame carrier_last_frame(RegisterMap* reg_map); 984 javaVFrame* carrier_last_java_vframe(RegisterMap* reg_map) { return last_java_vframe(carrier_last_frame(reg_map), reg_map); } 985 986 frame vthread_last_frame(); 987 javaVFrame* vthread_last_java_vframe(RegisterMap* reg_map) { return last_java_vframe(vthread_last_frame(), reg_map); } 988 989 frame platform_thread_last_frame(RegisterMap* reg_map); 990 javaVFrame* platform_thread_last_java_vframe(RegisterMap* reg_map) { 991 return last_java_vframe(platform_thread_last_frame(reg_map), reg_map); 992 } 993 994 javaVFrame* last_java_vframe(const frame f, RegisterMap* reg_map); 995 996 // Returns method at 'depth' java or native frames down the stack 997 // Used for security checks 998 Klass* security_get_caller_class(int depth); 999 1000 // Print stack trace in external format 1001 // These variants print carrier/platform thread information only. 1002 void print_stack_on(outputStream* st); 1003 void print_stack() { print_stack_on(tty); } 1004 // This prints the currently mounted virtual thread. 1005 void print_vthread_stack_on(outputStream* st); 1006 // This prints the active stack: either carrier/platform or virtual. 1007 void print_active_stack_on(outputStream* st); 1008 // Print current stack trace for checked JNI warnings and JNI fatal errors. 1009 // This is the external format from above, but selecting the platform 1010 // or vthread as applicable. 1011 void print_jni_stack(); 1012 1013 // Print stack traces in various internal formats 1014 void trace_stack() PRODUCT_RETURN; 1015 void trace_stack_from(vframe* start_vf) PRODUCT_RETURN; 1016 void trace_frames() PRODUCT_RETURN; 1017 1018 // Print an annotated view of the stack frames 1019 void print_frame_layout(int depth = 0, bool validate_only = false) NOT_DEBUG_RETURN; 1020 void validate_frame_layout() { 1021 print_frame_layout(0, true); 1022 } 1023 1024 // Function for testing deoptimization 1025 void deoptimize(); 1026 void make_zombies(); 1027 1028 void deoptimize_marked_methods(); 1029 1030 public: 1031 // Returns the running thread as a JavaThread 1032 static JavaThread* current() { 1033 return JavaThread::cast(Thread::current()); 1034 } 1035 1036 // Returns the current thread as a JavaThread, or nullptr if not attached 1037 static inline JavaThread* current_or_null(); 1038 1039 // Casts 1040 static JavaThread* cast(Thread* t) { 1041 assert(t->is_Java_thread(), "incorrect cast to JavaThread"); 1042 return static_cast<JavaThread*>(t); 1043 } 1044 1045 static const JavaThread* cast(const Thread* t) { 1046 assert(t->is_Java_thread(), "incorrect cast to const JavaThread"); 1047 return static_cast<const JavaThread*>(t); 1048 } 1049 1050 // Returns the active Java thread. Do not use this if you know you are calling 1051 // from a JavaThread, as it's slower than JavaThread::current. If called from 1052 // the VMThread, it also returns the JavaThread that instigated the VMThread's 1053 // operation. You may not want that either. 1054 static JavaThread* active(); 1055 1056 protected: 1057 virtual void pre_run(); 1058 virtual void run(); 1059 void thread_main_inner(); 1060 virtual void post_run(); 1061 1062 public: 1063 // Thread local information maintained by JVMTI. 1064 void set_jvmti_thread_state(JvmtiThreadState *value) { _jvmti_thread_state = value; } 1065 // A JvmtiThreadState is lazily allocated. This jvmti_thread_state() 1066 // getter is used to get this JavaThread's JvmtiThreadState if it has 1067 // one which means null can be returned. JvmtiThreadState::state_for() 1068 // is used to get the specified JavaThread's JvmtiThreadState if it has 1069 // one or it allocates a new JvmtiThreadState for the JavaThread and 1070 // returns it. JvmtiThreadState::state_for() will return null only if 1071 // the specified JavaThread is exiting. 1072 JvmtiThreadState *jvmti_thread_state() const { return _jvmti_thread_state; } 1073 static ByteSize jvmti_thread_state_offset() { return byte_offset_of(JavaThread, _jvmti_thread_state); } 1074 1075 #if INCLUDE_JVMTI 1076 // Rebind JVMTI thread state from carrier to virtual or from virtual to carrier. 1077 JvmtiThreadState *rebind_to_jvmti_thread_state_of(oop thread_oop); 1078 #endif 1079 1080 // JVMTI PopFrame support 1081 // Setting and clearing popframe_condition 1082 // All of these enumerated values are bits. popframe_pending 1083 // indicates that a PopFrame() has been requested and not yet been 1084 // completed. popframe_processing indicates that that PopFrame() is in 1085 // the process of being completed. popframe_force_deopt_reexecution_bit 1086 // indicates that special handling is required when returning to a 1087 // deoptimized caller. 1088 enum PopCondition { 1089 popframe_inactive = 0x00, 1090 popframe_pending_bit = 0x01, 1091 popframe_processing_bit = 0x02, 1092 popframe_force_deopt_reexecution_bit = 0x04 1093 }; 1094 PopCondition popframe_condition() { return (PopCondition) _popframe_condition; } 1095 void set_popframe_condition(PopCondition c) { _popframe_condition = c; } 1096 void set_popframe_condition_bit(PopCondition c) { _popframe_condition |= c; } 1097 void clear_popframe_condition() { _popframe_condition = popframe_inactive; } 1098 static ByteSize popframe_condition_offset() { return byte_offset_of(JavaThread, _popframe_condition); } 1099 bool has_pending_popframe() { return (popframe_condition() & popframe_pending_bit) != 0; } 1100 bool popframe_forcing_deopt_reexecution() { return (popframe_condition() & popframe_force_deopt_reexecution_bit) != 0; } 1101 1102 bool pop_frame_in_process(void) { return ((_popframe_condition & popframe_processing_bit) != 0); } 1103 void set_pop_frame_in_process(void) { _popframe_condition |= popframe_processing_bit; } 1104 void clr_pop_frame_in_process(void) { _popframe_condition &= ~popframe_processing_bit; } 1105 1106 int frames_to_pop_failed_realloc() const { return _frames_to_pop_failed_realloc; } 1107 void set_frames_to_pop_failed_realloc(int nb) { _frames_to_pop_failed_realloc = nb; } 1108 void dec_frames_to_pop_failed_realloc() { _frames_to_pop_failed_realloc--; } 1109 1110 private: 1111 // Saved incoming arguments to popped frame. 1112 // Used only when popped interpreted frame returns to deoptimized frame. 1113 void* _popframe_preserved_args; 1114 int _popframe_preserved_args_size; 1115 1116 public: 1117 void popframe_preserve_args(ByteSize size_in_bytes, void* start); 1118 void* popframe_preserved_args(); 1119 ByteSize popframe_preserved_args_size(); 1120 WordSize popframe_preserved_args_size_in_words(); 1121 void popframe_free_preserved_args(); 1122 1123 1124 private: 1125 JvmtiThreadState *_jvmti_thread_state; 1126 1127 // Used by the interpreter in fullspeed mode for frame pop, method 1128 // entry, method exit and single stepping support. This field is 1129 // only set to non-zero at a safepoint or using a direct handshake 1130 // (see EnterInterpOnlyModeClosure). 1131 // It can be set to zero asynchronously to this threads execution (i.e., without 1132 // safepoint/handshake or a lock) so we have to be very careful. 1133 // Accesses by other threads are synchronized using JvmtiThreadState_lock though. 1134 int _interp_only_mode; 1135 1136 public: 1137 // used by the interpreter for fullspeed debugging support (see above) 1138 static ByteSize interp_only_mode_offset() { return byte_offset_of(JavaThread, _interp_only_mode); } 1139 bool is_interp_only_mode() { return (_interp_only_mode != 0); } 1140 int get_interp_only_mode() { return _interp_only_mode; } 1141 int set_interp_only_mode(int val) { return _interp_only_mode = val; } 1142 void increment_interp_only_mode() { ++_interp_only_mode; } 1143 void decrement_interp_only_mode() { --_interp_only_mode; } 1144 1145 // support for cached flag that indicates whether exceptions need to be posted for this thread 1146 // if this is false, we can avoid deoptimizing when events are thrown 1147 // this gets set to reflect whether jvmtiExport::post_exception_throw would actually do anything 1148 private: 1149 int _should_post_on_exceptions_flag; 1150 1151 public: 1152 void set_should_post_on_exceptions_flag(int val) { _should_post_on_exceptions_flag = val; } 1153 1154 private: 1155 ThreadStatistics *_thread_stat; 1156 1157 public: 1158 ThreadStatistics* get_thread_stat() const { return _thread_stat; } 1159 1160 // Return a blocker object for which this thread is blocked parking. 1161 oop current_park_blocker(); 1162 1163 private: 1164 static size_t _stack_size_at_create; 1165 1166 public: 1167 static inline size_t stack_size_at_create(void) { 1168 return _stack_size_at_create; 1169 } 1170 static inline void set_stack_size_at_create(size_t value) { 1171 _stack_size_at_create = value; 1172 } 1173 1174 // Machine dependent stuff 1175 #include OS_CPU_HEADER(javaThread) 1176 1177 // JSR166 per-thread parker 1178 private: 1179 Parker _parker; 1180 public: 1181 Parker* parker() { return &_parker; } 1182 1183 public: 1184 // clearing/querying jni attach status 1185 bool is_attaching_via_jni() const { return _jni_attach_state == _attaching_via_jni; } 1186 bool has_attached_via_jni() const { return is_attaching_via_jni() || _jni_attach_state == _attached_via_jni; } 1187 inline void set_done_attaching_via_jni(); 1188 1189 // Stack dump assistance: 1190 // Track the class we want to initialize but for which we have to wait 1191 // on its init_lock() because it is already being initialized. 1192 void set_class_to_be_initialized(InstanceKlass* k); 1193 InstanceKlass* class_to_be_initialized() const; 1194 1195 private: 1196 InstanceKlass* _class_to_be_initialized; 1197 1198 // java.lang.Thread.sleep support 1199 ParkEvent * _SleepEvent; 1200 public: 1201 bool sleep(jlong millis); 1202 bool sleep_nanos(jlong nanos); 1203 1204 // java.lang.Thread interruption support 1205 void interrupt(); 1206 bool is_interrupted(bool clear_interrupted); 1207 1208 // This is only for use by JVMTI RawMonitorWait. It emulates the actions of 1209 // the Java code in Object::wait which are not present in RawMonitorWait. 1210 bool get_and_clear_interrupted(); 1211 1212 private: 1213 LockStack _lock_stack; 1214 1215 public: 1216 LockStack& lock_stack() { return _lock_stack; } 1217 1218 static ByteSize lock_stack_offset() { return byte_offset_of(JavaThread, _lock_stack); } 1219 // Those offsets are used in code generators to access the LockStack that is embedded in this 1220 // JavaThread structure. Those accesses are relative to the current thread, which 1221 // is typically in a dedicated register. 1222 static ByteSize lock_stack_top_offset() { return lock_stack_offset() + LockStack::top_offset(); } 1223 static ByteSize lock_stack_base_offset() { return lock_stack_offset() + LockStack::base_offset(); } 1224 1225 static OopStorage* thread_oop_storage(); 1226 1227 static void verify_cross_modify_fence_failure(JavaThread *thread) PRODUCT_RETURN; 1228 1229 // Helper function to create the java.lang.Thread object for a 1230 // VM-internal thread. The thread will have the given name and be 1231 // part of the System ThreadGroup. 1232 static Handle create_system_thread_object(const char* name, TRAPS); 1233 1234 // Helper function to start a VM-internal daemon thread. 1235 // E.g. ServiceThread, NotificationThread, CompilerThread etc. 1236 static void start_internal_daemon(JavaThread* current, JavaThread* target, 1237 Handle thread_oop, ThreadPriority prio); 1238 1239 // Helper function to do vm_exit_on_initialization for osthread 1240 // resource allocation failure. 1241 static void vm_exit_on_osthread_failure(JavaThread* thread); 1242 1243 // Deferred OopHandle release support 1244 private: 1245 // List of OopHandles to be released - guarded by the Service_lock. 1246 static OopHandleList* _oop_handle_list; 1247 // Add our OopHandles to the list for the service thread to release. 1248 void add_oop_handles_for_release(); 1249 // Called by the ServiceThread to release the OopHandles. 1250 static void release_oop_handles(); 1251 // Called by the ServiceThread to poll if there are any OopHandles to release. 1252 // Called when holding the Service_lock. 1253 static bool has_oop_handles_to_release() { 1254 return _oop_handle_list != nullptr; 1255 } 1256 }; 1257 1258 inline JavaThread* JavaThread::current_or_null() { 1259 Thread* current = Thread::current_or_null(); 1260 return current != nullptr ? JavaThread::cast(current) : nullptr; 1261 } 1262 1263 class UnlockFlagSaver { 1264 private: 1265 JavaThread* _thread; 1266 bool _do_not_unlock; 1267 public: 1268 UnlockFlagSaver(JavaThread* t) { 1269 _thread = t; 1270 _do_not_unlock = t->do_not_unlock_if_synchronized(); 1271 t->set_do_not_unlock_if_synchronized(false); 1272 } 1273 ~UnlockFlagSaver() { 1274 _thread->set_do_not_unlock_if_synchronized(_do_not_unlock); 1275 } 1276 }; 1277 1278 class JNIHandleMark : public StackObj { 1279 JavaThread* _thread; 1280 public: 1281 JNIHandleMark(JavaThread* thread) : _thread(thread) { 1282 thread->push_jni_handle_block(); 1283 } 1284 ~JNIHandleMark() { _thread->pop_jni_handle_block(); } 1285 }; 1286 1287 class ThreadOnMonitorEnter { 1288 JavaThread* _thread; 1289 public: 1290 ThreadOnMonitorEnter(JavaThread* thread) : _thread(thread) { 1291 _thread->set_on_monitorenter(true); 1292 } 1293 ~ThreadOnMonitorEnter() { _thread->set_on_monitorenter(false); } 1294 }; 1295 1296 #endif // SHARE_RUNTIME_JAVATHREAD_HPP