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