1 /* 2 * Copyright (c) 1997, 2018, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. 8 * 9 * This code is distributed in the hope that it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 12 * version 2 for more details (a copy is included in the LICENSE file that 13 * accompanied this code). 14 * 15 * You should have received a copy of the GNU General Public License version 16 * 2 along with this work; if not, write to the Free Software Foundation, 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 18 * 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 20 * or visit www.oracle.com if you need additional information or have any 21 * questions. 22 * 23 */ 24 25 #ifndef SHARE_VM_RUNTIME_THREAD_HPP 26 #define SHARE_VM_RUNTIME_THREAD_HPP 27 28 #include "jni.h" 29 #include "code/compiledMethod.hpp" 30 #include "gc/shared/gcThreadLocalData.hpp" 31 #include "gc/shared/threadLocalAllocBuffer.hpp" 32 #include "memory/allocation.hpp" 33 #include "oops/oop.hpp" 34 #include "prims/jvmtiExport.hpp" 35 #include "runtime/frame.hpp" 36 #include "runtime/globals.hpp" 37 #include "runtime/handshake.hpp" 38 #include "runtime/javaFrameAnchor.hpp" 39 #include "runtime/jniHandles.hpp" 40 #include "runtime/mutexLocker.hpp" 41 #include "runtime/os.hpp" 42 #include "runtime/osThread.hpp" 43 #include "runtime/park.hpp" 44 #include "runtime/stubRoutines.hpp" 45 #include "runtime/threadHeapSampler.hpp" 46 #include "runtime/threadLocalStorage.hpp" 47 #include "runtime/threadStatisticalInfo.hpp" 48 #include "runtime/unhandledOops.hpp" 49 #include "utilities/align.hpp" 50 #include "utilities/exceptions.hpp" 51 #include "utilities/macros.hpp" 52 #ifdef ZERO 53 # include "stack_zero.hpp" 54 #endif 55 #if INCLUDE_JFR 56 #include "jfr/support/jfrThreadExtension.hpp" 57 #endif 58 59 60 class SafeThreadsListPtr; 61 class ThreadSafepointState; 62 class ThreadsList; 63 class ThreadsSMRSupport; 64 65 class JvmtiThreadState; 66 class ThreadStatistics; 67 class ConcurrentLocksDump; 68 class ParkEvent; 69 class Parker; 70 71 class ciEnv; 72 class CompileThread; 73 class CompileLog; 74 class CompileTask; 75 class CompileQueue; 76 class CompilerCounters; 77 class vframeArray; 78 79 class DeoptResourceMark; 80 class jvmtiDeferredLocalVariableSet; 81 82 class GCTaskQueue; 83 class ThreadClosure; 84 class IdealGraphPrinter; 85 86 class Metadata; 87 template <class T, MEMFLAGS F> class ChunkedList; 88 typedef ChunkedList<Metadata*, mtInternal> MetadataOnStackBuffer; 89 90 DEBUG_ONLY(class ResourceMark;) 91 92 class WorkerThread; 93 94 // Class hierarchy 95 // - Thread 96 // - JavaThread 97 // - various subclasses eg CompilerThread, ServiceThread 98 // - NonJavaThread 99 // - NamedThread 100 // - VMThread 101 // - ConcurrentGCThread 102 // - WorkerThread 103 // - GangWorker 104 // - GCTaskThread 105 // - WatcherThread 106 // - JfrThreadSampler 107 // 108 // All Thread subclasses must be either JavaThread or NonJavaThread. 109 // This means !t->is_Java_thread() iff t is a NonJavaThread, or t is 110 // a partially constructed/destroyed Thread. 111 112 /* 113 Thread execution sequence and actions: 114 115 All threads: 116 - thread_native_entry // per-OS native entry point 117 - stack initialization 118 - other OS-level initialization (signal masks etc) 119 - handshake with creating thread (if not started suspended) 120 - this->call_run() // common shared entry point 121 - shared common initialization 122 - this->pre_run() // virtual per-thread-type initialization 123 - this->run() // virtual per-thread-type "main" logic 124 - shared common tear-down 125 - this->post_run() // virtual per-thread-type tear-down 126 - // 'this' no longer referenceable 127 - OS-level tear-down (minimal) 128 - final logging 129 130 For JavaThread: 131 - this->run() // virtual but not normally overridden 132 - this->thread_main_inner() // extra call level to ensure correct stack calculations 133 - this->entry_point() // set differently for each kind of JavaThread 134 135 */ 136 137 class Thread: public ThreadShadow { 138 friend class VMStructs; 139 friend class JVMCIVMStructs; 140 private: 141 142 #ifndef USE_LIBRARY_BASED_TLS_ONLY 143 // Current thread is maintained as a thread-local variable 144 static THREAD_LOCAL_DECL Thread* _thr_current; 145 #endif 146 147 // Thread local data area available to the GC. The internal 148 // structure and contents of this data area is GC-specific. 149 // Only GC and GC barrier code should access this data area. 150 GCThreadLocalData _gc_data; 151 152 public: 153 static ByteSize gc_data_offset() { 154 return byte_offset_of(Thread, _gc_data); 155 } 156 157 template <typename T> T* gc_data() { 158 STATIC_ASSERT(sizeof(T) <= sizeof(_gc_data)); 159 return reinterpret_cast<T*>(&_gc_data); 160 } 161 162 // Exception handling 163 // (Note: _pending_exception and friends are in ThreadShadow) 164 //oop _pending_exception; // pending exception for current thread 165 // const char* _exception_file; // file information for exception (debugging only) 166 // int _exception_line; // line information for exception (debugging only) 167 protected: 168 169 DEBUG_ONLY(static Thread* _starting_thread;) 170 171 // Support for forcing alignment of thread objects for biased locking 172 void* _real_malloc_address; 173 174 // JavaThread lifecycle support: 175 friend class SafeThreadsListPtr; // for _threads_list_ptr, cmpxchg_threads_hazard_ptr(), {dec_,inc_,}nested_threads_hazard_ptr_cnt(), {g,s}et_threads_hazard_ptr(), inc_nested_handle_cnt(), tag_hazard_ptr() access 176 friend class ScanHazardPtrGatherProtectedThreadsClosure; // for cmpxchg_threads_hazard_ptr(), get_threads_hazard_ptr(), is_hazard_ptr_tagged() access 177 friend class ScanHazardPtrGatherThreadsListClosure; // for get_threads_hazard_ptr(), untag_hazard_ptr() access 178 friend class ScanHazardPtrPrintMatchingThreadsClosure; // for get_threads_hazard_ptr(), is_hazard_ptr_tagged() access 179 friend class ThreadsSMRSupport; // for _nested_threads_hazard_ptr_cnt, _threads_hazard_ptr, _threads_list_ptr access 180 181 ThreadsList* volatile _threads_hazard_ptr; 182 SafeThreadsListPtr* _threads_list_ptr; 183 ThreadsList* cmpxchg_threads_hazard_ptr(ThreadsList* exchange_value, ThreadsList* compare_value); 184 ThreadsList* get_threads_hazard_ptr(); 185 void set_threads_hazard_ptr(ThreadsList* new_list); 186 static bool is_hazard_ptr_tagged(ThreadsList* list) { 187 return (intptr_t(list) & intptr_t(1)) == intptr_t(1); 188 } 189 static ThreadsList* tag_hazard_ptr(ThreadsList* list) { 190 return (ThreadsList*)(intptr_t(list) | intptr_t(1)); 191 } 192 static ThreadsList* untag_hazard_ptr(ThreadsList* list) { 193 return (ThreadsList*)(intptr_t(list) & ~intptr_t(1)); 194 } 195 // This field is enabled via -XX:+EnableThreadSMRStatistics: 196 uint _nested_threads_hazard_ptr_cnt; 197 void dec_nested_threads_hazard_ptr_cnt() { 198 assert(_nested_threads_hazard_ptr_cnt != 0, "mismatched {dec,inc}_nested_threads_hazard_ptr_cnt()"); 199 _nested_threads_hazard_ptr_cnt--; 200 } 201 void inc_nested_threads_hazard_ptr_cnt() { 202 _nested_threads_hazard_ptr_cnt++; 203 } 204 uint nested_threads_hazard_ptr_cnt() { 205 return _nested_threads_hazard_ptr_cnt; 206 } 207 208 public: 209 void* operator new(size_t size) throw() { return allocate(size, true); } 210 void* operator new(size_t size, const std::nothrow_t& nothrow_constant) throw() { 211 return allocate(size, false); } 212 void operator delete(void* p); 213 214 protected: 215 static void* allocate(size_t size, bool throw_excpt, MEMFLAGS flags = mtThread); 216 private: 217 218 // *************************************************************** 219 // Suspend and resume support 220 // *************************************************************** 221 // 222 // VM suspend/resume no longer exists - it was once used for various 223 // things including safepoints but was deprecated and finally removed 224 // in Java 7. Because VM suspension was considered "internal" Java-level 225 // suspension was considered "external", and this legacy naming scheme 226 // remains. 227 // 228 // External suspend/resume requests come from JVM_SuspendThread, 229 // JVM_ResumeThread, JVMTI SuspendThread, and finally JVMTI 230 // ResumeThread. External 231 // suspend requests cause _external_suspend to be set and external 232 // resume requests cause _external_suspend to be cleared. 233 // External suspend requests do not nest on top of other external 234 // suspend requests. The higher level APIs reject suspend requests 235 // for already suspended threads. 236 // 237 // The external_suspend 238 // flag is checked by has_special_runtime_exit_condition() and java thread 239 // will self-suspend when handle_special_runtime_exit_condition() is 240 // called. Most uses of the _thread_blocked state in JavaThreads are 241 // considered the same as being externally suspended; if the blocking 242 // condition lifts, the JavaThread will self-suspend. Other places 243 // where VM checks for external_suspend include: 244 // + mutex granting (do not enter monitors when thread is suspended) 245 // + state transitions from _thread_in_native 246 // 247 // In general, java_suspend() does not wait for an external suspend 248 // request to complete. When it returns, the only guarantee is that 249 // the _external_suspend field is true. 250 // 251 // wait_for_ext_suspend_completion() is used to wait for an external 252 // suspend request to complete. External suspend requests are usually 253 // followed by some other interface call that requires the thread to 254 // be quiescent, e.g., GetCallTrace(). By moving the "wait time" into 255 // the interface that requires quiescence, we give the JavaThread a 256 // chance to self-suspend before we need it to be quiescent. This 257 // improves overall suspend/query performance. 258 // 259 // _suspend_flags controls the behavior of java_ suspend/resume. 260 // It must be set under the protection of SR_lock. Read from the flag is 261 // OK without SR_lock as long as the value is only used as a hint. 262 // (e.g., check _external_suspend first without lock and then recheck 263 // inside SR_lock and finish the suspension) 264 // 265 // _suspend_flags is also overloaded for other "special conditions" so 266 // that a single check indicates whether any special action is needed 267 // eg. for async exceptions. 268 // ------------------------------------------------------------------- 269 // Notes: 270 // 1. The suspend/resume logic no longer uses ThreadState in OSThread 271 // but we still update its value to keep other part of the system (mainly 272 // JVMTI) happy. ThreadState is legacy code (see notes in 273 // osThread.hpp). 274 // 275 // 2. It would be more natural if set_external_suspend() is private and 276 // part of java_suspend(), but that probably would affect the suspend/query 277 // performance. Need more investigation on this. 278 279 // suspend/resume lock: used for self-suspend 280 Monitor* _SR_lock; 281 282 protected: 283 enum SuspendFlags { 284 // NOTE: avoid using the sign-bit as cc generates different test code 285 // when the sign-bit is used, and sometimes incorrectly - see CR 6398077 286 287 _external_suspend = 0x20000000U, // thread is asked to self suspend 288 _ext_suspended = 0x40000000U, // thread has self-suspended 289 _deopt_suspend = 0x10000000U, // thread needs to self suspend for deopt 290 291 _has_async_exception = 0x00000001U, // there is a pending async exception 292 _critical_native_unlock = 0x00000002U, // Must call back to unlock JNI critical lock 293 294 _trace_flag = 0x00000004U // call tracing backend 295 }; 296 297 // various suspension related flags - atomically updated 298 // overloaded for async exception checking in check_special_condition_for_native_trans. 299 volatile uint32_t _suspend_flags; 300 301 private: 302 int _num_nested_signal; 303 304 DEBUG_ONLY(bool _suspendible_thread;) 305 306 public: 307 void enter_signal_handler() { _num_nested_signal++; } 308 void leave_signal_handler() { _num_nested_signal--; } 309 bool is_inside_signal_handler() const { return _num_nested_signal > 0; } 310 311 // Determines if a heap allocation failure will be retried 312 // (e.g., by deoptimizing and re-executing in the interpreter). 313 // In this case, the failed allocation must raise 314 // Universe::out_of_memory_error_retry() and omit side effects 315 // such as JVMTI events and handling -XX:+HeapDumpOnOutOfMemoryError 316 // and -XX:OnOutOfMemoryError. 317 virtual bool in_retryable_allocation() const { return false; } 318 319 #ifdef ASSERT 320 void set_suspendible_thread() { 321 _suspendible_thread = true; 322 } 323 324 void clear_suspendible_thread() { 325 _suspendible_thread = false; 326 } 327 328 bool is_suspendible_thread() { return _suspendible_thread; } 329 #endif 330 331 private: 332 // Active_handles points to a block of handles 333 JNIHandleBlock* _active_handles; 334 335 // One-element thread local free list 336 JNIHandleBlock* _free_handle_block; 337 338 // Point to the last handle mark 339 HandleMark* _last_handle_mark; 340 341 // The parity of the last strong_roots iteration in which this thread was 342 // claimed as a task. 343 int _oops_do_parity; 344 345 // Support for GlobalCounter 346 private: 347 volatile uintx _rcu_counter; 348 public: 349 volatile uintx* get_rcu_counter() { 350 return &_rcu_counter; 351 } 352 353 public: 354 void set_last_handle_mark(HandleMark* mark) { _last_handle_mark = mark; } 355 HandleMark* last_handle_mark() const { return _last_handle_mark; } 356 private: 357 358 #ifdef ASSERT 359 void* _missed_ic_stub_refill_mark; 360 361 public: 362 void* missed_ic_stub_refill_mark() { 363 return _missed_ic_stub_refill_mark; 364 } 365 366 void set_missed_ic_stub_refill_mark(void* mark) { 367 _missed_ic_stub_refill_mark = mark; 368 } 369 #endif 370 371 private: 372 373 // debug support for checking if code does allow safepoints or not 374 // GC points in the VM can happen because of allocation, invoking a VM operation, or blocking on 375 // mutex, or blocking on an object synchronizer (Java locking). 376 // If !allow_safepoint(), then an assertion failure will happen in any of the above cases 377 // If !allow_allocation(), then an assertion failure will happen during allocation 378 // (Hence, !allow_safepoint() => !allow_allocation()). 379 // 380 // The two classes NoSafepointVerifier and No_Allocation_Verifier are used to set these counters. 381 // 382 NOT_PRODUCT(int _allow_safepoint_count;) // If 0, thread allow a safepoint to happen 383 debug_only(int _allow_allocation_count;) // If 0, the thread is allowed to allocate oops. 384 385 // Used by SkipGCALot class. 386 NOT_PRODUCT(bool _skip_gcalot;) // Should we elide gc-a-lot? 387 388 friend class NoAllocVerifier; 389 friend class NoSafepointVerifier; 390 friend class PauseNoSafepointVerifier; 391 friend class GCLocker; 392 393 volatile void* _polling_page; // Thread local polling page 394 395 ThreadLocalAllocBuffer _tlab; // Thread-local eden 396 jlong _allocated_bytes; // Cumulative number of bytes allocated on 397 // the Java heap 398 ThreadHeapSampler _heap_sampler; // For use when sampling the memory. 399 400 ThreadStatisticalInfo _statistical_info; // Statistics about the thread 401 402 JFR_ONLY(DEFINE_THREAD_LOCAL_FIELD_JFR;) // Thread-local data for jfr 403 404 int _vm_operation_started_count; // VM_Operation support 405 int _vm_operation_completed_count; // VM_Operation support 406 407 ObjectMonitor* _current_pending_monitor; // ObjectMonitor this thread 408 // is waiting to lock 409 bool _current_pending_monitor_is_from_java; // locking is from Java code 410 411 // ObjectMonitor on which this thread called Object.wait() 412 ObjectMonitor* _current_waiting_monitor; 413 414 // Private thread-local objectmonitor list - a simple cache organized as a SLL. 415 public: 416 ObjectMonitor* omFreeList; 417 int omFreeCount; // length of omFreeList 418 int omFreeProvision; // reload chunk size 419 ObjectMonitor* omInUseList; // SLL to track monitors in circulation 420 int omInUseCount; // length of omInUseList 421 422 #ifdef ASSERT 423 private: 424 bool _visited_for_critical_count; 425 426 public: 427 void set_visited_for_critical_count(bool z) { _visited_for_critical_count = z; } 428 bool was_visited_for_critical_count() const { return _visited_for_critical_count; } 429 #endif 430 431 public: 432 enum { 433 is_definitely_current_thread = true 434 }; 435 436 // Constructor 437 Thread(); 438 virtual ~Thread() = 0; // Thread is abstract. 439 440 // Manage Thread::current() 441 void initialize_thread_current(); 442 static void clear_thread_current(); // TLS cleanup needed before threads terminate 443 444 protected: 445 // To be implemented by children. 446 virtual void run() = 0; 447 virtual void pre_run() = 0; 448 virtual void post_run() = 0; // Note: Thread must not be deleted prior to calling this! 449 450 #ifdef ASSERT 451 enum RunState { 452 PRE_CALL_RUN, 453 CALL_RUN, 454 PRE_RUN, 455 RUN, 456 POST_RUN 457 // POST_CALL_RUN - can't define this one as 'this' may be deleted when we want to set it 458 }; 459 RunState _run_state; // for lifecycle checks 460 #endif 461 462 463 public: 464 // invokes <ChildThreadClass>::run(), with common preparations and cleanups. 465 void call_run(); 466 467 // Testers 468 virtual bool is_VM_thread() const { return false; } 469 virtual bool is_Java_thread() const { return false; } 470 virtual bool is_Compiler_thread() const { return false; } 471 virtual bool is_Code_cache_sweeper_thread() const { return false; } 472 virtual bool is_hidden_from_external_view() const { return false; } 473 virtual bool is_jvmti_agent_thread() const { return false; } 474 // True iff the thread can perform GC operations at a safepoint. 475 // Generally will be true only of VM thread and parallel GC WorkGang 476 // threads. 477 virtual bool is_GC_task_thread() const { return false; } 478 virtual bool is_Watcher_thread() const { return false; } 479 virtual bool is_ConcurrentGC_thread() const { return false; } 480 virtual bool is_Named_thread() const { return false; } 481 virtual bool is_Worker_thread() const { return false; } 482 483 // Can this thread make Java upcalls 484 virtual bool can_call_java() const { return false; } 485 486 // Casts 487 virtual WorkerThread* as_Worker_thread() const { return NULL; } 488 489 virtual char* name() const { return (char*)"Unknown thread"; } 490 491 // Returns the current thread (ASSERTS if NULL) 492 static inline Thread* current(); 493 // Returns the current thread, or NULL if not attached 494 static inline Thread* current_or_null(); 495 // Returns the current thread, or NULL if not attached, and is 496 // safe for use from signal-handlers 497 static inline Thread* current_or_null_safe(); 498 499 // Common thread operations 500 #ifdef ASSERT 501 static void check_for_dangling_thread_pointer(Thread *thread); 502 #endif 503 static void set_priority(Thread* thread, ThreadPriority priority); 504 static ThreadPriority get_priority(const Thread* const thread); 505 static void start(Thread* thread); 506 static void interrupt(Thread* thr); 507 static bool is_interrupted(Thread* thr, bool clear_interrupted); 508 509 void set_native_thread_name(const char *name) { 510 assert(Thread::current() == this, "set_native_thread_name can only be called on the current thread"); 511 os::set_native_thread_name(name); 512 } 513 514 ObjectMonitor** omInUseList_addr() { return (ObjectMonitor **)&omInUseList; } 515 Monitor* SR_lock() const { return _SR_lock; } 516 517 bool has_async_exception() const { return (_suspend_flags & _has_async_exception) != 0; } 518 519 inline void set_suspend_flag(SuspendFlags f); 520 inline void clear_suspend_flag(SuspendFlags f); 521 522 inline void set_has_async_exception(); 523 inline void clear_has_async_exception(); 524 525 bool do_critical_native_unlock() const { return (_suspend_flags & _critical_native_unlock) != 0; } 526 527 inline void set_critical_native_unlock(); 528 inline void clear_critical_native_unlock(); 529 530 inline void set_trace_flag(); 531 inline void clear_trace_flag(); 532 533 // Support for Unhandled Oop detection 534 // Add the field for both, fastdebug and debug, builds to keep 535 // Thread's fields layout the same. 536 // Note: CHECK_UNHANDLED_OOPS is defined only for fastdebug build. 537 #ifdef CHECK_UNHANDLED_OOPS 538 private: 539 UnhandledOops* _unhandled_oops; 540 #elif defined(ASSERT) 541 private: 542 void* _unhandled_oops; 543 #endif 544 #ifdef CHECK_UNHANDLED_OOPS 545 public: 546 UnhandledOops* unhandled_oops() { return _unhandled_oops; } 547 // Mark oop safe for gc. It may be stack allocated but won't move. 548 void allow_unhandled_oop(oop *op) { 549 if (CheckUnhandledOops) unhandled_oops()->allow_unhandled_oop(op); 550 } 551 // Clear oops at safepoint so crashes point to unhandled oop violator 552 void clear_unhandled_oops() { 553 if (CheckUnhandledOops) unhandled_oops()->clear_unhandled_oops(); 554 } 555 #endif // CHECK_UNHANDLED_OOPS 556 557 public: 558 #ifndef PRODUCT 559 bool skip_gcalot() { return _skip_gcalot; } 560 void set_skip_gcalot(bool v) { _skip_gcalot = v; } 561 #endif 562 563 // Installs a pending exception to be inserted later 564 static void send_async_exception(oop thread_oop, oop java_throwable); 565 566 // Resource area 567 ResourceArea* resource_area() const { return _resource_area; } 568 void set_resource_area(ResourceArea* area) { _resource_area = area; } 569 570 OSThread* osthread() const { return _osthread; } 571 void set_osthread(OSThread* thread) { _osthread = thread; } 572 573 // JNI handle support 574 JNIHandleBlock* active_handles() const { return _active_handles; } 575 void set_active_handles(JNIHandleBlock* block) { _active_handles = block; } 576 JNIHandleBlock* free_handle_block() const { return _free_handle_block; } 577 void set_free_handle_block(JNIHandleBlock* block) { _free_handle_block = block; } 578 579 // Internal handle support 580 HandleArea* handle_area() const { return _handle_area; } 581 void set_handle_area(HandleArea* area) { _handle_area = area; } 582 583 GrowableArray<Metadata*>* metadata_handles() const { return _metadata_handles; } 584 void set_metadata_handles(GrowableArray<Metadata*>* handles){ _metadata_handles = handles; } 585 586 // Thread-Local Allocation Buffer (TLAB) support 587 ThreadLocalAllocBuffer& tlab() { return _tlab; } 588 void initialize_tlab() { 589 if (UseTLAB) { 590 tlab().initialize(); 591 } 592 } 593 594 jlong allocated_bytes() { return _allocated_bytes; } 595 void set_allocated_bytes(jlong value) { _allocated_bytes = value; } 596 void incr_allocated_bytes(jlong size) { _allocated_bytes += size; } 597 inline jlong cooked_allocated_bytes(); 598 599 ThreadHeapSampler& heap_sampler() { return _heap_sampler; } 600 601 ThreadStatisticalInfo& statistical_info() { return _statistical_info; } 602 603 JFR_ONLY(DEFINE_THREAD_LOCAL_ACCESSOR_JFR;) 604 605 bool is_trace_suspend() { return (_suspend_flags & _trace_flag) != 0; } 606 607 // VM operation support 608 int vm_operation_ticket() { return ++_vm_operation_started_count; } 609 int vm_operation_completed_count() { return _vm_operation_completed_count; } 610 void increment_vm_operation_completed_count() { _vm_operation_completed_count++; } 611 612 // For tracking the heavyweight monitor the thread is pending on. 613 ObjectMonitor* current_pending_monitor() { 614 return _current_pending_monitor; 615 } 616 void set_current_pending_monitor(ObjectMonitor* monitor) { 617 _current_pending_monitor = monitor; 618 } 619 void set_current_pending_monitor_is_from_java(bool from_java) { 620 _current_pending_monitor_is_from_java = from_java; 621 } 622 bool current_pending_monitor_is_from_java() { 623 return _current_pending_monitor_is_from_java; 624 } 625 626 // For tracking the ObjectMonitor on which this thread called Object.wait() 627 ObjectMonitor* current_waiting_monitor() { 628 return _current_waiting_monitor; 629 } 630 void set_current_waiting_monitor(ObjectMonitor* monitor) { 631 _current_waiting_monitor = monitor; 632 } 633 634 // GC support 635 // Apply "f->do_oop" to all root oops in "this". 636 // Used by JavaThread::oops_do. 637 // Apply "cf->do_code_blob" (if !NULL) to all code blobs active in frames 638 virtual void oops_do(OopClosure* f, CodeBlobClosure* cf); 639 640 // Handles the parallel case for the method below. 641 private: 642 bool claim_oops_do_par_case(int collection_parity); 643 public: 644 // Requires that "collection_parity" is that of the current roots 645 // iteration. If "is_par" is false, sets the parity of "this" to 646 // "collection_parity", and returns "true". If "is_par" is true, 647 // uses an atomic instruction to set the current threads parity to 648 // "collection_parity", if it is not already. Returns "true" iff the 649 // calling thread does the update, this indicates that the calling thread 650 // has claimed the thread's stack as a root groop in the current 651 // collection. 652 bool claim_oops_do(bool is_par, int collection_parity) { 653 if (!is_par) { 654 _oops_do_parity = collection_parity; 655 return true; 656 } else { 657 return claim_oops_do_par_case(collection_parity); 658 } 659 } 660 661 // jvmtiRedefineClasses support 662 void metadata_handles_do(void f(Metadata*)); 663 664 // Used by fast lock support 665 virtual bool is_lock_owned(address adr) const; 666 667 // Check if address is in the stack of the thread (not just for locks). 668 // Warning: the method can only be used on the running thread 669 bool is_in_stack(address adr) const; 670 // Check if address is in the usable part of the stack (excludes protected 671 // guard pages) 672 bool is_in_usable_stack(address adr) const; 673 674 // Sets this thread as starting thread. Returns failure if thread 675 // creation fails due to lack of memory, too many threads etc. 676 bool set_as_starting_thread(); 677 678 protected: 679 // OS data associated with the thread 680 OSThread* _osthread; // Platform-specific thread information 681 682 // Thread local resource area for temporary allocation within the VM 683 ResourceArea* _resource_area; 684 685 DEBUG_ONLY(ResourceMark* _current_resource_mark;) 686 687 // Thread local handle area for allocation of handles within the VM 688 HandleArea* _handle_area; 689 GrowableArray<Metadata*>* _metadata_handles; 690 691 // Support for stack overflow handling, get_thread, etc. 692 address _stack_base; 693 size_t _stack_size; 694 uintptr_t _self_raw_id; // used by get_thread (mutable) 695 int _lgrp_id; 696 697 volatile void** polling_page_addr() { return &_polling_page; } 698 699 public: 700 // Stack overflow support 701 address stack_base() const { assert(_stack_base != NULL,"Sanity check"); return _stack_base; } 702 void set_stack_base(address base) { _stack_base = base; } 703 size_t stack_size() const { return _stack_size; } 704 void set_stack_size(size_t size) { _stack_size = size; } 705 address stack_end() const { return stack_base() - stack_size(); } 706 void record_stack_base_and_size(); 707 void register_thread_stack_with_NMT() NOT_NMT_RETURN; 708 709 bool on_local_stack(address adr) const { 710 // QQQ this has knowledge of direction, ought to be a stack method 711 return (_stack_base >= adr && adr >= stack_end()); 712 } 713 714 uintptr_t self_raw_id() { return _self_raw_id; } 715 void set_self_raw_id(uintptr_t value) { _self_raw_id = value; } 716 717 int lgrp_id() const { return _lgrp_id; } 718 void set_lgrp_id(int value) { _lgrp_id = value; } 719 720 // Printing 721 void print_on(outputStream* st, bool print_extended_info) const; 722 virtual void print_on(outputStream* st) const { print_on(st, false); } 723 void print() const { print_on(tty); } 724 virtual void print_on_error(outputStream* st, char* buf, int buflen) const; 725 void print_value_on(outputStream* st) const; 726 727 // Debug-only code 728 #ifdef ASSERT 729 private: 730 // Deadlock detection support for Mutex locks. List of locks own by thread. 731 Monitor* _owned_locks; 732 // Mutex::set_owner_implementation is the only place where _owned_locks is modified, 733 // thus the friendship 734 friend class Mutex; 735 friend class Monitor; 736 737 public: 738 void print_owned_locks_on(outputStream* st) const; 739 void print_owned_locks() const { print_owned_locks_on(tty); } 740 Monitor* owned_locks() const { return _owned_locks; } 741 bool owns_locks() const { return owned_locks() != NULL; } 742 bool owns_locks_but_compiled_lock() const; 743 int oops_do_parity() const { return _oops_do_parity; } 744 745 // Deadlock detection 746 bool allow_allocation() { return _allow_allocation_count == 0; } 747 ResourceMark* current_resource_mark() { return _current_resource_mark; } 748 void set_current_resource_mark(ResourceMark* rm) { _current_resource_mark = rm; } 749 #endif 750 751 void check_for_valid_safepoint_state(bool potential_vm_operation) PRODUCT_RETURN; 752 753 private: 754 volatile int _jvmti_env_iteration_count; 755 756 public: 757 void entering_jvmti_env_iteration() { ++_jvmti_env_iteration_count; } 758 void leaving_jvmti_env_iteration() { --_jvmti_env_iteration_count; } 759 bool is_inside_jvmti_env_iteration() { return _jvmti_env_iteration_count > 0; } 760 761 // Code generation 762 static ByteSize exception_file_offset() { return byte_offset_of(Thread, _exception_file); } 763 static ByteSize exception_line_offset() { return byte_offset_of(Thread, _exception_line); } 764 static ByteSize active_handles_offset() { return byte_offset_of(Thread, _active_handles); } 765 766 static ByteSize stack_base_offset() { return byte_offset_of(Thread, _stack_base); } 767 static ByteSize stack_size_offset() { return byte_offset_of(Thread, _stack_size); } 768 769 static ByteSize polling_page_offset() { return byte_offset_of(Thread, _polling_page); } 770 771 static ByteSize tlab_start_offset() { return byte_offset_of(Thread, _tlab) + ThreadLocalAllocBuffer::start_offset(); } 772 static ByteSize tlab_end_offset() { return byte_offset_of(Thread, _tlab) + ThreadLocalAllocBuffer::end_offset(); } 773 static ByteSize tlab_top_offset() { return byte_offset_of(Thread, _tlab) + ThreadLocalAllocBuffer::top_offset(); } 774 static ByteSize tlab_pf_top_offset() { return byte_offset_of(Thread, _tlab) + ThreadLocalAllocBuffer::pf_top_offset(); } 775 776 static ByteSize allocated_bytes_offset() { return byte_offset_of(Thread, _allocated_bytes); } 777 778 JFR_ONLY(DEFINE_THREAD_LOCAL_OFFSET_JFR;) 779 780 public: 781 volatile intptr_t _Stalled; 782 volatile int _TypeTag; 783 ParkEvent * _ParkEvent; // for synchronized() 784 ParkEvent * _SleepEvent; // for Thread.sleep 785 ParkEvent * _MutexEvent; // for native internal Mutex/Monitor 786 ParkEvent * _MuxEvent; // for low-level muxAcquire-muxRelease 787 int NativeSyncRecursion; // diagnostic 788 789 volatile int _OnTrap; // Resume-at IP delta 790 jint _hashStateW; // Marsaglia Shift-XOR thread-local RNG 791 jint _hashStateX; // thread-specific hashCode generator state 792 jint _hashStateY; 793 jint _hashStateZ; 794 795 volatile jint rng[4]; // RNG for spin loop 796 797 // Low-level leaf-lock primitives used to implement synchronization 798 // and native monitor-mutex infrastructure. 799 // Not for general synchronization use. 800 static void SpinAcquire(volatile int * Lock, const char * Name); 801 static void SpinRelease(volatile int * Lock); 802 static void muxAcquire(volatile intptr_t * Lock, const char * Name); 803 static void muxAcquireW(volatile intptr_t * Lock, ParkEvent * ev); 804 static void muxRelease(volatile intptr_t * Lock); 805 }; 806 807 // Inline implementation of Thread::current() 808 inline Thread* Thread::current() { 809 Thread* current = current_or_null(); 810 assert(current != NULL, "Thread::current() called on detached thread"); 811 return current; 812 } 813 814 inline Thread* Thread::current_or_null() { 815 #ifndef USE_LIBRARY_BASED_TLS_ONLY 816 return _thr_current; 817 #else 818 if (ThreadLocalStorage::is_initialized()) { 819 return ThreadLocalStorage::thread(); 820 } 821 return NULL; 822 #endif 823 } 824 825 inline Thread* Thread::current_or_null_safe() { 826 if (ThreadLocalStorage::is_initialized()) { 827 return ThreadLocalStorage::thread(); 828 } 829 return NULL; 830 } 831 832 class NonJavaThread: public Thread { 833 friend class VMStructs; 834 835 NonJavaThread* volatile _next; 836 837 class List; 838 static List _the_list; 839 840 void add_to_the_list(); 841 void remove_from_the_list(); 842 843 protected: 844 virtual void pre_run(); 845 virtual void post_run(); 846 847 public: 848 NonJavaThread(); 849 ~NonJavaThread(); 850 851 class Iterator; 852 }; 853 854 // Provides iteration over the list of NonJavaThreads. 855 // Normal list addition occurs in pre_run(), and removal occurs 856 // in post_run(), so that only live fully-initialized threads can 857 // be found in the list. There is a special case during VM startup 858 // when the BarrierSet has not yet been created, where we add to the 859 // list during the constructor. That set of initial threads (the main 860 // thread, plus GC threads typically) is iterated over when the 861 // BarrierSet is set and each thread is manually updated. The fact those 862 // threads may not yet have executed is not an issue for that code. 863 // However it is possible that those threads may still not have executed 864 // by the time subsequent iterators are created and used - but they are 865 // known to be fully initialized by their creating thread. 866 // Threads created after an iterator is constructed 867 // will not be visited by the iterator. The scope of an iterator is a 868 // critical section; there must be no safepoint checks in that scope. 869 class NonJavaThread::Iterator : public StackObj { 870 uint _protect_enter; 871 NonJavaThread* _current; 872 873 // Noncopyable. 874 Iterator(const Iterator&); 875 Iterator& operator=(const Iterator&); 876 877 public: 878 Iterator(); 879 ~Iterator(); 880 881 bool end() const { return _current == NULL; } 882 NonJavaThread* current() const { return _current; } 883 void step(); 884 }; 885 886 // Name support for threads. non-JavaThread subclasses with multiple 887 // uniquely named instances should derive from this. 888 class NamedThread: public NonJavaThread { 889 friend class VMStructs; 890 enum { 891 max_name_len = 64 892 }; 893 private: 894 char* _name; 895 // log JavaThread being processed by oops_do 896 JavaThread* _processed_thread; 897 uint _gc_id; // The current GC id when a thread takes part in GC 898 899 public: 900 NamedThread(); 901 ~NamedThread(); 902 // May only be called once per thread. 903 void set_name(const char* format, ...) ATTRIBUTE_PRINTF(2, 3); 904 virtual bool is_Named_thread() const { return true; } 905 virtual char* name() const { return _name == NULL ? (char*)"Unknown Thread" : _name; } 906 JavaThread *processed_thread() { return _processed_thread; } 907 void set_processed_thread(JavaThread *thread) { _processed_thread = thread; } 908 virtual void print_on(outputStream* st) const; 909 910 void set_gc_id(uint gc_id) { _gc_id = gc_id; } 911 uint gc_id() { return _gc_id; } 912 }; 913 914 // Worker threads are named and have an id of an assigned work. 915 class WorkerThread: public NamedThread { 916 private: 917 uint _id; 918 public: 919 WorkerThread() : _id(0) { } 920 virtual bool is_Worker_thread() const { return true; } 921 922 virtual WorkerThread* as_Worker_thread() const { 923 assert(is_Worker_thread(), "Dubious cast to WorkerThread*?"); 924 return (WorkerThread*) this; 925 } 926 927 void set_id(uint work_id) { _id = work_id; } 928 uint id() const { return _id; } 929 }; 930 931 // A single WatcherThread is used for simulating timer interrupts. 932 class WatcherThread: public NonJavaThread { 933 friend class VMStructs; 934 protected: 935 virtual void run(); 936 937 private: 938 static WatcherThread* _watcher_thread; 939 940 static bool _startable; 941 // volatile due to at least one lock-free read 942 volatile static bool _should_terminate; 943 public: 944 enum SomeConstants { 945 delay_interval = 10 // interrupt delay in milliseconds 946 }; 947 948 // Constructor 949 WatcherThread(); 950 951 // No destruction allowed 952 ~WatcherThread() { 953 guarantee(false, "WatcherThread deletion must fix the race with VM termination"); 954 } 955 956 // Tester 957 bool is_Watcher_thread() const { return true; } 958 959 // Printing 960 char* name() const { return (char*)"VM Periodic Task Thread"; } 961 void print_on(outputStream* st) const; 962 void unpark(); 963 964 // Returns the single instance of WatcherThread 965 static WatcherThread* watcher_thread() { return _watcher_thread; } 966 967 // Create and start the single instance of WatcherThread, or stop it on shutdown 968 static void start(); 969 static void stop(); 970 // Only allow start once the VM is sufficiently initialized 971 // Otherwise the first task to enroll will trigger the start 972 static void make_startable(); 973 private: 974 int sleep() const; 975 }; 976 977 978 class CompilerThread; 979 980 typedef void (*ThreadFunction)(JavaThread*, TRAPS); 981 982 class JavaThread: public Thread { 983 friend class VMStructs; 984 friend class JVMCIVMStructs; 985 friend class WhiteBox; 986 private: 987 JavaThread* _next; // The next thread in the Threads list 988 bool _on_thread_list; // Is set when this JavaThread is added to the Threads list 989 oop _threadObj; // The Java level thread object 990 991 #ifdef ASSERT 992 private: 993 int _java_call_counter; 994 995 public: 996 int java_call_counter() { return _java_call_counter; } 997 void inc_java_call_counter() { _java_call_counter++; } 998 void dec_java_call_counter() { 999 assert(_java_call_counter > 0, "Invalid nesting of JavaCallWrapper"); 1000 _java_call_counter--; 1001 } 1002 private: // restore original namespace restriction 1003 #endif // ifdef ASSERT 1004 1005 #ifndef PRODUCT 1006 public: 1007 enum { 1008 jump_ring_buffer_size = 16 1009 }; 1010 private: // restore original namespace restriction 1011 #endif 1012 1013 JavaFrameAnchor _anchor; // Encapsulation of current java frame and it state 1014 1015 ThreadFunction _entry_point; 1016 1017 JNIEnv _jni_environment; 1018 1019 // Deopt support 1020 DeoptResourceMark* _deopt_mark; // Holds special ResourceMark for deoptimization 1021 1022 intptr_t* _must_deopt_id; // id of frame that needs to be deopted once we 1023 // transition out of native 1024 CompiledMethod* _deopt_nmethod; // CompiledMethod that is currently being deoptimized 1025 vframeArray* _vframe_array_head; // Holds the heap of the active vframeArrays 1026 vframeArray* _vframe_array_last; // Holds last vFrameArray we popped 1027 // Because deoptimization is lazy we must save jvmti requests to set locals 1028 // in compiled frames until we deoptimize and we have an interpreter frame. 1029 // This holds the pointer to array (yeah like there might be more than one) of 1030 // description of compiled vframes that have locals that need to be updated. 1031 GrowableArray<jvmtiDeferredLocalVariableSet*>* _deferred_locals_updates; 1032 1033 // Handshake value for fixing 6243940. We need a place for the i2c 1034 // adapter to store the callee Method*. This value is NEVER live 1035 // across a gc point so it does NOT have to be gc'd 1036 // The handshake is open ended since we can't be certain that it will 1037 // be NULLed. This is because we rarely ever see the race and end up 1038 // in handle_wrong_method which is the backend of the handshake. See 1039 // code in i2c adapters and handle_wrong_method. 1040 1041 Method* _callee_target; 1042 1043 // Used to pass back results to the interpreter or generated code running Java code. 1044 oop _vm_result; // oop result is GC-preserved 1045 Metadata* _vm_result_2; // non-oop result 1046 1047 // See ReduceInitialCardMarks: this holds the precise space interval of 1048 // the most recent slow path allocation for which compiled code has 1049 // elided card-marks for performance along the fast-path. 1050 MemRegion _deferred_card_mark; 1051 1052 MonitorChunk* _monitor_chunks; // Contains the off stack monitors 1053 // allocated during deoptimization 1054 // and by JNI_MonitorEnter/Exit 1055 1056 // Async. requests support 1057 enum AsyncRequests { 1058 _no_async_condition = 0, 1059 _async_exception, 1060 _async_unsafe_access_error 1061 }; 1062 AsyncRequests _special_runtime_exit_condition; // Enum indicating pending async. request 1063 oop _pending_async_exception; 1064 1065 // Safepoint support 1066 public: // Expose _thread_state for SafeFetchInt() 1067 volatile JavaThreadState _thread_state; 1068 private: 1069 ThreadSafepointState* _safepoint_state; // Holds information about a thread during a safepoint 1070 address _saved_exception_pc; // Saved pc of instruction where last implicit exception happened 1071 1072 // JavaThread termination support 1073 enum TerminatedTypes { 1074 _not_terminated = 0xDEAD - 2, 1075 _thread_exiting, // JavaThread::exit() has been called for this thread 1076 _thread_terminated, // JavaThread is removed from thread list 1077 _vm_exited // JavaThread is still executing native code, but VM is terminated 1078 // only VM_Exit can set _vm_exited 1079 }; 1080 1081 // In general a JavaThread's _terminated field transitions as follows: 1082 // 1083 // _not_terminated => _thread_exiting => _thread_terminated 1084 // 1085 // _vm_exited is a special value to cover the case of a JavaThread 1086 // executing native code after the VM itself is terminated. 1087 volatile TerminatedTypes _terminated; 1088 // suspend/resume support 1089 volatile bool _suspend_equivalent; // Suspend equivalent condition 1090 jint _in_deopt_handler; // count of deoptimization 1091 // handlers thread is in 1092 volatile bool _doing_unsafe_access; // Thread may fault due to unsafe access 1093 bool _do_not_unlock_if_synchronized; // Do not unlock the receiver of a synchronized method (since it was 1094 // never locked) when throwing an exception. Used by interpreter only. 1095 1096 // JNI attach states: 1097 enum JNIAttachStates { 1098 _not_attaching_via_jni = 1, // thread is not attaching via JNI 1099 _attaching_via_jni, // thread is attaching via JNI 1100 _attached_via_jni // thread has attached via JNI 1101 }; 1102 1103 // A regular JavaThread's _jni_attach_state is _not_attaching_via_jni. 1104 // A native thread that is attaching via JNI starts with a value 1105 // of _attaching_via_jni and transitions to _attached_via_jni. 1106 volatile JNIAttachStates _jni_attach_state; 1107 1108 public: 1109 // State of the stack guard pages for this thread. 1110 enum StackGuardState { 1111 stack_guard_unused, // not needed 1112 stack_guard_reserved_disabled, 1113 stack_guard_yellow_reserved_disabled,// disabled (temporarily) after stack overflow 1114 stack_guard_enabled // enabled 1115 }; 1116 1117 private: 1118 1119 #if INCLUDE_JVMCI 1120 // The _pending_* fields below are used to communicate extra information 1121 // from an uncommon trap in JVMCI compiled code to the uncommon trap handler. 1122 1123 // Communicates the DeoptReason and DeoptAction of the uncommon trap 1124 int _pending_deoptimization; 1125 1126 // Specifies whether the uncommon trap is to bci 0 of a synchronized method 1127 // before the monitor has been acquired. 1128 bool _pending_monitorenter; 1129 1130 // Specifies if the DeoptReason for the last uncommon trap was Reason_transfer_to_interpreter 1131 bool _pending_transfer_to_interpreter; 1132 1133 // Guard for re-entrant call to JVMCIRuntime::adjust_comp_level 1134 bool _adjusting_comp_level; 1135 1136 // True if in a runtime call from compiled code that will deoptimize 1137 // and re-execute a failed heap allocation in the interpreter. 1138 bool _in_retryable_allocation; 1139 1140 // An id of a speculation that JVMCI compiled code can use to further describe and 1141 // uniquely identify the speculative optimization guarded by the uncommon trap 1142 long _pending_failed_speculation; 1143 1144 // These fields are mutually exclusive in terms of live ranges. 1145 union { 1146 // Communicates the pc at which the most recent implicit exception occurred 1147 // from the signal handler to a deoptimization stub. 1148 address _implicit_exception_pc; 1149 1150 // Communicates an alternative call target to an i2c stub from a JavaCall . 1151 address _alternate_call_target; 1152 } _jvmci; 1153 1154 // Support for high precision, thread sensitive counters in JVMCI compiled code. 1155 jlong* _jvmci_counters; 1156 1157 public: 1158 static jlong* _jvmci_old_thread_counters; 1159 static void collect_counters(typeArrayOop array); 1160 private: 1161 #endif // INCLUDE_JVMCI 1162 1163 StackGuardState _stack_guard_state; 1164 1165 // Precompute the limit of the stack as used in stack overflow checks. 1166 // We load it from here to simplify the stack overflow check in assembly. 1167 address _stack_overflow_limit; 1168 address _reserved_stack_activation; 1169 1170 // Compiler exception handling (NOTE: The _exception_oop is *NOT* the same as _pending_exception. It is 1171 // used to temp. parsing values into and out of the runtime system during exception handling for compiled 1172 // code) 1173 volatile oop _exception_oop; // Exception thrown in compiled code 1174 volatile address _exception_pc; // PC where exception happened 1175 volatile address _exception_handler_pc; // PC for handler of exception 1176 volatile int _is_method_handle_return; // true (== 1) if the current exception PC is a MethodHandle call site. 1177 1178 private: 1179 // support for JNI critical regions 1180 jint _jni_active_critical; // count of entries into JNI critical region 1181 1182 // Checked JNI: function name requires exception check 1183 char* _pending_jni_exception_check_fn; 1184 1185 // For deadlock detection. 1186 int _depth_first_number; 1187 1188 // JVMTI PopFrame support 1189 // This is set to popframe_pending to signal that top Java frame should be popped immediately 1190 int _popframe_condition; 1191 1192 // If reallocation of scalar replaced objects fails, we throw OOM 1193 // and during exception propagation, pop the top 1194 // _frames_to_pop_failed_realloc frames, the ones that reference 1195 // failed reallocations. 1196 int _frames_to_pop_failed_realloc; 1197 1198 #ifndef PRODUCT 1199 int _jmp_ring_index; 1200 struct { 1201 // We use intptr_t instead of address so debugger doesn't try and display strings 1202 intptr_t _target; 1203 intptr_t _instruction; 1204 const char* _file; 1205 int _line; 1206 } _jmp_ring[jump_ring_buffer_size]; 1207 #endif // PRODUCT 1208 1209 friend class VMThread; 1210 friend class ThreadWaitTransition; 1211 friend class VM_Exit; 1212 1213 void initialize(); // Initialized the instance variables 1214 1215 public: 1216 // Constructor 1217 JavaThread(bool is_attaching_via_jni = false); // for main thread and JNI attached threads 1218 JavaThread(ThreadFunction entry_point, size_t stack_size = 0); 1219 ~JavaThread(); 1220 1221 #ifdef ASSERT 1222 // verify this JavaThread hasn't be published in the Threads::list yet 1223 void verify_not_published(); 1224 #endif 1225 1226 //JNI functiontable getter/setter for JVMTI jni function table interception API. 1227 void set_jni_functions(struct JNINativeInterface_* functionTable) { 1228 _jni_environment.functions = functionTable; 1229 } 1230 struct JNINativeInterface_* get_jni_functions() { 1231 return (struct JNINativeInterface_ *)_jni_environment.functions; 1232 } 1233 1234 // This function is called at thread creation to allow 1235 // platform specific thread variables to be initialized. 1236 void cache_global_variables(); 1237 1238 // Executes Shutdown.shutdown() 1239 void invoke_shutdown_hooks(); 1240 1241 // Cleanup on thread exit 1242 enum ExitType { 1243 normal_exit, 1244 jni_detach 1245 }; 1246 void exit(bool destroy_vm, ExitType exit_type = normal_exit); 1247 1248 void cleanup_failed_attach_current_thread(); 1249 1250 // Testers 1251 virtual bool is_Java_thread() const { return true; } 1252 virtual bool can_call_java() const { return true; } 1253 1254 // Thread chain operations 1255 JavaThread* next() const { return _next; } 1256 void set_next(JavaThread* p) { _next = p; } 1257 1258 // Thread oop. threadObj() can be NULL for initial JavaThread 1259 // (or for threads attached via JNI) 1260 oop threadObj() const { return _threadObj; } 1261 void set_threadObj(oop p) { _threadObj = p; } 1262 1263 ThreadPriority java_priority() const; // Read from threadObj() 1264 1265 // Prepare thread and add to priority queue. If a priority is 1266 // not specified, use the priority of the thread object. Threads_lock 1267 // must be held while this function is called. 1268 void prepare(jobject jni_thread, ThreadPriority prio=NoPriority); 1269 1270 void set_saved_exception_pc(address pc) { _saved_exception_pc = pc; } 1271 address saved_exception_pc() { return _saved_exception_pc; } 1272 1273 1274 ThreadFunction entry_point() const { return _entry_point; } 1275 1276 // Allocates a new Java level thread object for this thread. thread_name may be NULL. 1277 void allocate_threadObj(Handle thread_group, const char* thread_name, bool daemon, TRAPS); 1278 1279 // Last frame anchor routines 1280 1281 JavaFrameAnchor* frame_anchor(void) { return &_anchor; } 1282 1283 // last_Java_sp 1284 bool has_last_Java_frame() const { return _anchor.has_last_Java_frame(); } 1285 intptr_t* last_Java_sp() const { return _anchor.last_Java_sp(); } 1286 1287 // last_Java_pc 1288 1289 address last_Java_pc(void) { return _anchor.last_Java_pc(); } 1290 1291 // Safepoint support 1292 #if !(defined(PPC64) || defined(AARCH64)) 1293 JavaThreadState thread_state() const { return _thread_state; } 1294 void set_thread_state(JavaThreadState s) { _thread_state = s; } 1295 #else 1296 // Use membars when accessing volatile _thread_state. See 1297 // Threads::create_vm() for size checks. 1298 inline JavaThreadState thread_state() const; 1299 inline void set_thread_state(JavaThreadState s); 1300 #endif 1301 inline ThreadSafepointState* safepoint_state() const; 1302 inline void set_safepoint_state(ThreadSafepointState* state); 1303 inline bool is_at_poll_safepoint(); 1304 1305 // JavaThread termination and lifecycle support: 1306 void smr_delete(); 1307 bool on_thread_list() const { return _on_thread_list; } 1308 void set_on_thread_list() { _on_thread_list = true; } 1309 1310 // thread has called JavaThread::exit() or is terminated 1311 bool is_exiting() const; 1312 // thread is terminated (no longer on the threads list); we compare 1313 // against the two non-terminated values so that a freed JavaThread 1314 // will also be considered terminated. 1315 bool check_is_terminated(TerminatedTypes l_terminated) const { 1316 return l_terminated != _not_terminated && l_terminated != _thread_exiting; 1317 } 1318 bool is_terminated() const; 1319 void set_terminated(TerminatedTypes t); 1320 // special for Threads::remove() which is static: 1321 void set_terminated_value(); 1322 void block_if_vm_exited(); 1323 1324 bool doing_unsafe_access() { return _doing_unsafe_access; } 1325 void set_doing_unsafe_access(bool val) { _doing_unsafe_access = val; } 1326 1327 bool do_not_unlock_if_synchronized() { return _do_not_unlock_if_synchronized; } 1328 void set_do_not_unlock_if_synchronized(bool val) { _do_not_unlock_if_synchronized = val; } 1329 1330 inline void set_polling_page_release(void* poll_value); 1331 inline void set_polling_page(void* poll_value); 1332 inline volatile void* get_polling_page(); 1333 1334 private: 1335 // Support for thread handshake operations 1336 HandshakeState _handshake; 1337 public: 1338 void set_handshake_operation(HandshakeOperation* op) { 1339 _handshake.set_operation(this, op); 1340 } 1341 1342 bool has_handshake() const { 1343 return _handshake.has_operation(); 1344 } 1345 1346 void handshake_process_by_self() { 1347 _handshake.process_by_self(this); 1348 } 1349 1350 void handshake_process_by_vmthread() { 1351 _handshake.process_by_vmthread(this); 1352 } 1353 1354 // Suspend/resume support for JavaThread 1355 private: 1356 inline void set_ext_suspended(); 1357 inline void clear_ext_suspended(); 1358 1359 public: 1360 void java_suspend(); 1361 void java_resume(); 1362 int java_suspend_self(); 1363 1364 void check_and_wait_while_suspended() { 1365 assert(JavaThread::current() == this, "sanity check"); 1366 1367 bool do_self_suspend; 1368 do { 1369 // were we externally suspended while we were waiting? 1370 do_self_suspend = handle_special_suspend_equivalent_condition(); 1371 if (do_self_suspend) { 1372 // don't surprise the thread that suspended us by returning 1373 java_suspend_self(); 1374 set_suspend_equivalent(); 1375 } 1376 } while (do_self_suspend); 1377 } 1378 static void check_safepoint_and_suspend_for_native_trans(JavaThread *thread); 1379 // Check for async exception in addition to safepoint and suspend request. 1380 static void check_special_condition_for_native_trans(JavaThread *thread); 1381 1382 // Same as check_special_condition_for_native_trans but finishes the 1383 // transition into thread_in_Java mode so that it can potentially 1384 // block. 1385 static void check_special_condition_for_native_trans_and_transition(JavaThread *thread); 1386 1387 bool is_ext_suspend_completed(bool called_by_wait, int delay, uint32_t *bits); 1388 bool is_ext_suspend_completed_with_lock(uint32_t *bits) { 1389 MutexLockerEx ml(SR_lock(), Mutex::_no_safepoint_check_flag); 1390 // Warning: is_ext_suspend_completed() may temporarily drop the 1391 // SR_lock to allow the thread to reach a stable thread state if 1392 // it is currently in a transient thread state. 1393 return is_ext_suspend_completed(false /* !called_by_wait */, 1394 SuspendRetryDelay, bits); 1395 } 1396 1397 // We cannot allow wait_for_ext_suspend_completion() to run forever or 1398 // we could hang. SuspendRetryCount and SuspendRetryDelay are normally 1399 // passed as the count and delay parameters. Experiments with specific 1400 // calls to wait_for_ext_suspend_completion() can be done by passing 1401 // other values in the code. Experiments with all calls can be done 1402 // via the appropriate -XX options. 1403 bool wait_for_ext_suspend_completion(int count, int delay, uint32_t *bits); 1404 1405 // test for suspend - most (all?) of these should go away 1406 bool is_thread_fully_suspended(bool wait_for_suspend, uint32_t *bits); 1407 1408 inline void set_external_suspend(); 1409 inline void clear_external_suspend(); 1410 1411 inline void set_deopt_suspend(); 1412 inline void clear_deopt_suspend(); 1413 bool is_deopt_suspend() { return (_suspend_flags & _deopt_suspend) != 0; } 1414 1415 bool is_external_suspend() const { 1416 return (_suspend_flags & _external_suspend) != 0; 1417 } 1418 // Whenever a thread transitions from native to vm/java it must suspend 1419 // if external|deopt suspend is present. 1420 bool is_suspend_after_native() const { 1421 return (_suspend_flags & (_external_suspend | _deopt_suspend)) != 0; 1422 } 1423 1424 // external suspend request is completed 1425 bool is_ext_suspended() const { 1426 return (_suspend_flags & _ext_suspended) != 0; 1427 } 1428 1429 bool is_external_suspend_with_lock() const { 1430 MutexLockerEx ml(SR_lock(), Mutex::_no_safepoint_check_flag); 1431 return is_external_suspend(); 1432 } 1433 1434 // Special method to handle a pending external suspend request 1435 // when a suspend equivalent condition lifts. 1436 bool handle_special_suspend_equivalent_condition() { 1437 assert(is_suspend_equivalent(), 1438 "should only be called in a suspend equivalence condition"); 1439 MutexLockerEx ml(SR_lock(), Mutex::_no_safepoint_check_flag); 1440 bool ret = is_external_suspend(); 1441 if (!ret) { 1442 // not about to self-suspend so clear suspend equivalence 1443 clear_suspend_equivalent(); 1444 } 1445 // implied else: 1446 // We have a pending external suspend request so we leave the 1447 // suspend_equivalent flag set until java_suspend_self() sets 1448 // the ext_suspended flag and clears the suspend_equivalent 1449 // flag. This insures that wait_for_ext_suspend_completion() 1450 // will return consistent values. 1451 return ret; 1452 } 1453 1454 // utility methods to see if we are doing some kind of suspension 1455 bool is_being_ext_suspended() const { 1456 MutexLockerEx ml(SR_lock(), Mutex::_no_safepoint_check_flag); 1457 return is_ext_suspended() || is_external_suspend(); 1458 } 1459 1460 bool is_suspend_equivalent() const { return _suspend_equivalent; } 1461 1462 void set_suspend_equivalent() { _suspend_equivalent = true; } 1463 void clear_suspend_equivalent() { _suspend_equivalent = false; } 1464 1465 // Thread.stop support 1466 void send_thread_stop(oop throwable); 1467 AsyncRequests clear_special_runtime_exit_condition() { 1468 AsyncRequests x = _special_runtime_exit_condition; 1469 _special_runtime_exit_condition = _no_async_condition; 1470 return x; 1471 } 1472 1473 // Are any async conditions present? 1474 bool has_async_condition() { return (_special_runtime_exit_condition != _no_async_condition); } 1475 1476 void check_and_handle_async_exceptions(bool check_unsafe_error = true); 1477 1478 // these next two are also used for self-suspension and async exception support 1479 void handle_special_runtime_exit_condition(bool check_asyncs = true); 1480 1481 // Return true if JavaThread has an asynchronous condition or 1482 // if external suspension is requested. 1483 bool has_special_runtime_exit_condition() { 1484 // Because we don't use is_external_suspend_with_lock 1485 // it is possible that we won't see an asynchronous external suspend 1486 // request that has just gotten started, i.e., SR_lock grabbed but 1487 // _external_suspend field change either not made yet or not visible 1488 // yet. However, this is okay because the request is asynchronous and 1489 // we will see the new flag value the next time through. It's also 1490 // possible that the external suspend request is dropped after 1491 // we have checked is_external_suspend(), we will recheck its value 1492 // under SR_lock in java_suspend_self(). 1493 return (_special_runtime_exit_condition != _no_async_condition) || 1494 is_external_suspend() || is_trace_suspend(); 1495 } 1496 1497 void set_pending_unsafe_access_error() { _special_runtime_exit_condition = _async_unsafe_access_error; } 1498 1499 inline void set_pending_async_exception(oop e); 1500 1501 // Fast-locking support 1502 bool is_lock_owned(address adr) const; 1503 1504 // Accessors for vframe array top 1505 // The linked list of vframe arrays are sorted on sp. This means when we 1506 // unpack the head must contain the vframe array to unpack. 1507 void set_vframe_array_head(vframeArray* value) { _vframe_array_head = value; } 1508 vframeArray* vframe_array_head() const { return _vframe_array_head; } 1509 1510 // Side structure for deferring update of java frame locals until deopt occurs 1511 GrowableArray<jvmtiDeferredLocalVariableSet*>* deferred_locals() const { return _deferred_locals_updates; } 1512 void set_deferred_locals(GrowableArray<jvmtiDeferredLocalVariableSet *>* vf) { _deferred_locals_updates = vf; } 1513 1514 // These only really exist to make debugging deopt problems simpler 1515 1516 void set_vframe_array_last(vframeArray* value) { _vframe_array_last = value; } 1517 vframeArray* vframe_array_last() const { return _vframe_array_last; } 1518 1519 // The special resourceMark used during deoptimization 1520 1521 void set_deopt_mark(DeoptResourceMark* value) { _deopt_mark = value; } 1522 DeoptResourceMark* deopt_mark(void) { return _deopt_mark; } 1523 1524 intptr_t* must_deopt_id() { return _must_deopt_id; } 1525 void set_must_deopt_id(intptr_t* id) { _must_deopt_id = id; } 1526 void clear_must_deopt_id() { _must_deopt_id = NULL; } 1527 1528 void set_deopt_compiled_method(CompiledMethod* nm) { _deopt_nmethod = nm; } 1529 CompiledMethod* deopt_compiled_method() { return _deopt_nmethod; } 1530 1531 Method* callee_target() const { return _callee_target; } 1532 void set_callee_target (Method* x) { _callee_target = x; } 1533 1534 // Oop results of vm runtime calls 1535 oop vm_result() const { return _vm_result; } 1536 void set_vm_result (oop x) { _vm_result = x; } 1537 1538 Metadata* vm_result_2() const { return _vm_result_2; } 1539 void set_vm_result_2 (Metadata* x) { _vm_result_2 = x; } 1540 1541 MemRegion deferred_card_mark() const { return _deferred_card_mark; } 1542 void set_deferred_card_mark(MemRegion mr) { _deferred_card_mark = mr; } 1543 1544 #if INCLUDE_JVMCI 1545 int pending_deoptimization() const { return _pending_deoptimization; } 1546 long pending_failed_speculation() const { return _pending_failed_speculation; } 1547 bool adjusting_comp_level() const { return _adjusting_comp_level; } 1548 void set_adjusting_comp_level(bool b) { _adjusting_comp_level = b; } 1549 bool has_pending_monitorenter() const { return _pending_monitorenter; } 1550 void set_pending_monitorenter(bool b) { _pending_monitorenter = b; } 1551 void set_pending_deoptimization(int reason) { _pending_deoptimization = reason; } 1552 void set_pending_failed_speculation(long failed_speculation) { _pending_failed_speculation = failed_speculation; } 1553 void set_pending_transfer_to_interpreter(bool b) { _pending_transfer_to_interpreter = b; } 1554 void set_jvmci_alternate_call_target(address a) { assert(_jvmci._alternate_call_target == NULL, "must be"); _jvmci._alternate_call_target = a; } 1555 void set_jvmci_implicit_exception_pc(address a) { assert(_jvmci._implicit_exception_pc == NULL, "must be"); _jvmci._implicit_exception_pc = a; } 1556 1557 virtual bool in_retryable_allocation() const { return _in_retryable_allocation; } 1558 void set_in_retryable_allocation(bool b) { _in_retryable_allocation = b; } 1559 #endif // INCLUDE_JVMCI 1560 1561 // Exception handling for compiled methods 1562 oop exception_oop() const { return _exception_oop; } 1563 address exception_pc() const { return _exception_pc; } 1564 address exception_handler_pc() const { return _exception_handler_pc; } 1565 bool is_method_handle_return() const { return _is_method_handle_return == 1; } 1566 1567 void set_exception_oop(oop o) { (void)const_cast<oop&>(_exception_oop = o); } 1568 void set_exception_pc(address a) { _exception_pc = a; } 1569 void set_exception_handler_pc(address a) { _exception_handler_pc = a; } 1570 void set_is_method_handle_return(bool value) { _is_method_handle_return = value ? 1 : 0; } 1571 1572 void clear_exception_oop_and_pc() { 1573 set_exception_oop(NULL); 1574 set_exception_pc(NULL); 1575 } 1576 1577 // Stack overflow support 1578 // 1579 // (small addresses) 1580 // 1581 // -- <-- stack_end() --- 1582 // | | 1583 // | red pages | 1584 // | | 1585 // -- <-- stack_red_zone_base() | 1586 // | | 1587 // | guard 1588 // | yellow pages zone 1589 // | | 1590 // | | 1591 // -- <-- stack_yellow_zone_base() | 1592 // | | 1593 // | | 1594 // | reserved pages | 1595 // | | 1596 // -- <-- stack_reserved_zone_base() --- --- 1597 // /|\ shadow <-- stack_overflow_limit() (somewhere in here) 1598 // | zone 1599 // \|/ size 1600 // some untouched memory --- 1601 // 1602 // 1603 // -- 1604 // | 1605 // | shadow zone 1606 // | 1607 // -- 1608 // x frame n 1609 // -- 1610 // x frame n-1 1611 // x 1612 // -- 1613 // ... 1614 // 1615 // -- 1616 // x frame 0 1617 // -- <-- stack_base() 1618 // 1619 // (large addresses) 1620 // 1621 1622 private: 1623 // These values are derived from flags StackRedPages, StackYellowPages, 1624 // StackReservedPages and StackShadowPages. The zone size is determined 1625 // ergonomically if page_size > 4K. 1626 static size_t _stack_red_zone_size; 1627 static size_t _stack_yellow_zone_size; 1628 static size_t _stack_reserved_zone_size; 1629 static size_t _stack_shadow_zone_size; 1630 public: 1631 inline size_t stack_available(address cur_sp); 1632 1633 static size_t stack_red_zone_size() { 1634 assert(_stack_red_zone_size > 0, "Don't call this before the field is initialized."); 1635 return _stack_red_zone_size; 1636 } 1637 static void set_stack_red_zone_size(size_t s) { 1638 assert(is_aligned(s, os::vm_page_size()), 1639 "We can not protect if the red zone size is not page aligned."); 1640 assert(_stack_red_zone_size == 0, "This should be called only once."); 1641 _stack_red_zone_size = s; 1642 } 1643 address stack_red_zone_base() { 1644 return (address)(stack_end() + stack_red_zone_size()); 1645 } 1646 bool in_stack_red_zone(address a) { 1647 return a <= stack_red_zone_base() && a >= stack_end(); 1648 } 1649 1650 static size_t stack_yellow_zone_size() { 1651 assert(_stack_yellow_zone_size > 0, "Don't call this before the field is initialized."); 1652 return _stack_yellow_zone_size; 1653 } 1654 static void set_stack_yellow_zone_size(size_t s) { 1655 assert(is_aligned(s, os::vm_page_size()), 1656 "We can not protect if the yellow zone size is not page aligned."); 1657 assert(_stack_yellow_zone_size == 0, "This should be called only once."); 1658 _stack_yellow_zone_size = s; 1659 } 1660 1661 static size_t stack_reserved_zone_size() { 1662 // _stack_reserved_zone_size may be 0. This indicates the feature is off. 1663 return _stack_reserved_zone_size; 1664 } 1665 static void set_stack_reserved_zone_size(size_t s) { 1666 assert(is_aligned(s, os::vm_page_size()), 1667 "We can not protect if the reserved zone size is not page aligned."); 1668 assert(_stack_reserved_zone_size == 0, "This should be called only once."); 1669 _stack_reserved_zone_size = s; 1670 } 1671 address stack_reserved_zone_base() { 1672 return (address)(stack_end() + 1673 (stack_red_zone_size() + stack_yellow_zone_size() + stack_reserved_zone_size())); 1674 } 1675 bool in_stack_reserved_zone(address a) { 1676 return (a <= stack_reserved_zone_base()) && 1677 (a >= (address)((intptr_t)stack_reserved_zone_base() - stack_reserved_zone_size())); 1678 } 1679 1680 static size_t stack_yellow_reserved_zone_size() { 1681 return _stack_yellow_zone_size + _stack_reserved_zone_size; 1682 } 1683 bool in_stack_yellow_reserved_zone(address a) { 1684 return (a <= stack_reserved_zone_base()) && (a >= stack_red_zone_base()); 1685 } 1686 1687 // Size of red + yellow + reserved zones. 1688 static size_t stack_guard_zone_size() { 1689 return stack_red_zone_size() + stack_yellow_reserved_zone_size(); 1690 } 1691 1692 static size_t stack_shadow_zone_size() { 1693 assert(_stack_shadow_zone_size > 0, "Don't call this before the field is initialized."); 1694 return _stack_shadow_zone_size; 1695 } 1696 static void set_stack_shadow_zone_size(size_t s) { 1697 // The shadow area is not allocated or protected, so 1698 // it needs not be page aligned. 1699 // But the stack bang currently assumes that it is a 1700 // multiple of page size. This guarantees that the bang 1701 // loop touches all pages in the shadow zone. 1702 // This can be guaranteed differently, as well. E.g., if 1703 // the page size is a multiple of 4K, banging in 4K steps 1704 // suffices to touch all pages. (Some pages are banged 1705 // several times, though.) 1706 assert(is_aligned(s, os::vm_page_size()), 1707 "Stack bang assumes multiple of page size."); 1708 assert(_stack_shadow_zone_size == 0, "This should be called only once."); 1709 _stack_shadow_zone_size = s; 1710 } 1711 1712 void create_stack_guard_pages(); 1713 void remove_stack_guard_pages(); 1714 1715 void enable_stack_reserved_zone(); 1716 void disable_stack_reserved_zone(); 1717 void enable_stack_yellow_reserved_zone(); 1718 void disable_stack_yellow_reserved_zone(); 1719 void enable_stack_red_zone(); 1720 void disable_stack_red_zone(); 1721 1722 inline bool stack_guard_zone_unused(); 1723 inline bool stack_yellow_reserved_zone_disabled(); 1724 inline bool stack_reserved_zone_disabled(); 1725 inline bool stack_guards_enabled(); 1726 1727 address reserved_stack_activation() const { return _reserved_stack_activation; } 1728 void set_reserved_stack_activation(address addr) { 1729 assert(_reserved_stack_activation == stack_base() 1730 || _reserved_stack_activation == NULL 1731 || addr == stack_base(), "Must not be set twice"); 1732 _reserved_stack_activation = addr; 1733 } 1734 1735 // Attempt to reguard the stack after a stack overflow may have occurred. 1736 // Returns true if (a) guard pages are not needed on this thread, (b) the 1737 // pages are already guarded, or (c) the pages were successfully reguarded. 1738 // Returns false if there is not enough stack space to reguard the pages, in 1739 // which case the caller should unwind a frame and try again. The argument 1740 // should be the caller's (approximate) sp. 1741 bool reguard_stack(address cur_sp); 1742 // Similar to above but see if current stackpoint is out of the guard area 1743 // and reguard if possible. 1744 bool reguard_stack(void); 1745 1746 address stack_overflow_limit() { return _stack_overflow_limit; } 1747 void set_stack_overflow_limit() { 1748 _stack_overflow_limit = 1749 stack_end() + MAX2(JavaThread::stack_guard_zone_size(), JavaThread::stack_shadow_zone_size()); 1750 } 1751 1752 // Misc. accessors/mutators 1753 void set_do_not_unlock(void) { _do_not_unlock_if_synchronized = true; } 1754 void clr_do_not_unlock(void) { _do_not_unlock_if_synchronized = false; } 1755 bool do_not_unlock(void) { return _do_not_unlock_if_synchronized; } 1756 1757 #ifndef PRODUCT 1758 void record_jump(address target, address instr, const char* file, int line); 1759 #endif // PRODUCT 1760 1761 // For assembly stub generation 1762 static ByteSize threadObj_offset() { return byte_offset_of(JavaThread, _threadObj); } 1763 #ifndef PRODUCT 1764 static ByteSize jmp_ring_index_offset() { return byte_offset_of(JavaThread, _jmp_ring_index); } 1765 static ByteSize jmp_ring_offset() { return byte_offset_of(JavaThread, _jmp_ring); } 1766 #endif // PRODUCT 1767 static ByteSize jni_environment_offset() { return byte_offset_of(JavaThread, _jni_environment); } 1768 static ByteSize pending_jni_exception_check_fn_offset() { 1769 return byte_offset_of(JavaThread, _pending_jni_exception_check_fn); 1770 } 1771 static ByteSize last_Java_sp_offset() { 1772 return byte_offset_of(JavaThread, _anchor) + JavaFrameAnchor::last_Java_sp_offset(); 1773 } 1774 static ByteSize last_Java_pc_offset() { 1775 return byte_offset_of(JavaThread, _anchor) + JavaFrameAnchor::last_Java_pc_offset(); 1776 } 1777 static ByteSize frame_anchor_offset() { 1778 return byte_offset_of(JavaThread, _anchor); 1779 } 1780 static ByteSize callee_target_offset() { return byte_offset_of(JavaThread, _callee_target); } 1781 static ByteSize vm_result_offset() { return byte_offset_of(JavaThread, _vm_result); } 1782 static ByteSize vm_result_2_offset() { return byte_offset_of(JavaThread, _vm_result_2); } 1783 static ByteSize thread_state_offset() { return byte_offset_of(JavaThread, _thread_state); } 1784 static ByteSize saved_exception_pc_offset() { return byte_offset_of(JavaThread, _saved_exception_pc); } 1785 static ByteSize osthread_offset() { return byte_offset_of(JavaThread, _osthread); } 1786 #if INCLUDE_JVMCI 1787 static ByteSize pending_deoptimization_offset() { return byte_offset_of(JavaThread, _pending_deoptimization); } 1788 static ByteSize pending_monitorenter_offset() { return byte_offset_of(JavaThread, _pending_monitorenter); } 1789 static ByteSize pending_failed_speculation_offset() { return byte_offset_of(JavaThread, _pending_failed_speculation); } 1790 static ByteSize jvmci_alternate_call_target_offset() { return byte_offset_of(JavaThread, _jvmci._alternate_call_target); } 1791 static ByteSize jvmci_implicit_exception_pc_offset() { return byte_offset_of(JavaThread, _jvmci._implicit_exception_pc); } 1792 static ByteSize jvmci_counters_offset() { return byte_offset_of(JavaThread, _jvmci_counters); } 1793 #endif // INCLUDE_JVMCI 1794 static ByteSize exception_oop_offset() { return byte_offset_of(JavaThread, _exception_oop); } 1795 static ByteSize exception_pc_offset() { return byte_offset_of(JavaThread, _exception_pc); } 1796 static ByteSize exception_handler_pc_offset() { return byte_offset_of(JavaThread, _exception_handler_pc); } 1797 static ByteSize stack_overflow_limit_offset() { return byte_offset_of(JavaThread, _stack_overflow_limit); } 1798 static ByteSize is_method_handle_return_offset() { return byte_offset_of(JavaThread, _is_method_handle_return); } 1799 static ByteSize stack_guard_state_offset() { return byte_offset_of(JavaThread, _stack_guard_state); } 1800 static ByteSize reserved_stack_activation_offset() { return byte_offset_of(JavaThread, _reserved_stack_activation); } 1801 static ByteSize suspend_flags_offset() { return byte_offset_of(JavaThread, _suspend_flags); } 1802 1803 static ByteSize do_not_unlock_if_synchronized_offset() { return byte_offset_of(JavaThread, _do_not_unlock_if_synchronized); } 1804 static ByteSize should_post_on_exceptions_flag_offset() { 1805 return byte_offset_of(JavaThread, _should_post_on_exceptions_flag); 1806 } 1807 1808 // Returns the jni environment for this thread 1809 JNIEnv* jni_environment() { return &_jni_environment; } 1810 1811 static JavaThread* thread_from_jni_environment(JNIEnv* env) { 1812 JavaThread *thread_from_jni_env = (JavaThread*)((intptr_t)env - in_bytes(jni_environment_offset())); 1813 // Only return NULL if thread is off the thread list; starting to 1814 // exit should not return NULL. 1815 if (thread_from_jni_env->is_terminated()) { 1816 thread_from_jni_env->block_if_vm_exited(); 1817 return NULL; 1818 } else { 1819 return thread_from_jni_env; 1820 } 1821 } 1822 1823 // JNI critical regions. These can nest. 1824 bool in_critical() { return _jni_active_critical > 0; } 1825 bool in_last_critical() { return _jni_active_critical == 1; } 1826 inline void enter_critical(); 1827 void exit_critical() { 1828 assert(Thread::current() == this, "this must be current thread"); 1829 _jni_active_critical--; 1830 assert(_jni_active_critical >= 0, "JNI critical nesting problem?"); 1831 } 1832 1833 // Checked JNI: is the programmer required to check for exceptions, if so specify 1834 // which function name. Returning to a Java frame should implicitly clear the 1835 // pending check, this is done for Native->Java transitions (i.e. user JNI code). 1836 // VM->Java transistions are not cleared, it is expected that JNI code enclosed 1837 // within ThreadToNativeFromVM makes proper exception checks (i.e. VM internal). 1838 bool is_pending_jni_exception_check() const { return _pending_jni_exception_check_fn != NULL; } 1839 void clear_pending_jni_exception_check() { _pending_jni_exception_check_fn = NULL; } 1840 const char* get_pending_jni_exception_check() const { return _pending_jni_exception_check_fn; } 1841 void set_pending_jni_exception_check(const char* fn_name) { _pending_jni_exception_check_fn = (char*) fn_name; } 1842 1843 // For deadlock detection 1844 int depth_first_number() { return _depth_first_number; } 1845 void set_depth_first_number(int dfn) { _depth_first_number = dfn; } 1846 1847 private: 1848 void set_monitor_chunks(MonitorChunk* monitor_chunks) { _monitor_chunks = monitor_chunks; } 1849 1850 public: 1851 MonitorChunk* monitor_chunks() const { return _monitor_chunks; } 1852 void add_monitor_chunk(MonitorChunk* chunk); 1853 void remove_monitor_chunk(MonitorChunk* chunk); 1854 bool in_deopt_handler() const { return _in_deopt_handler > 0; } 1855 void inc_in_deopt_handler() { _in_deopt_handler++; } 1856 void dec_in_deopt_handler() { 1857 assert(_in_deopt_handler > 0, "mismatched deopt nesting"); 1858 if (_in_deopt_handler > 0) { // robustness 1859 _in_deopt_handler--; 1860 } 1861 } 1862 1863 private: 1864 void set_entry_point(ThreadFunction entry_point) { _entry_point = entry_point; } 1865 1866 public: 1867 1868 // Frame iteration; calls the function f for all frames on the stack 1869 void frames_do(void f(frame*, const RegisterMap*)); 1870 1871 // Memory operations 1872 void oops_do(OopClosure* f, CodeBlobClosure* cf); 1873 1874 // Sweeper operations 1875 virtual void nmethods_do(CodeBlobClosure* cf); 1876 1877 // RedefineClasses Support 1878 void metadata_do(void f(Metadata*)); 1879 1880 // Misc. operations 1881 char* name() const { return (char*)get_thread_name(); } 1882 void print_on(outputStream* st, bool print_extended_info) const; 1883 void print_on(outputStream* st) const { print_on(st, false); } 1884 void print_value(); 1885 void print_thread_state_on(outputStream*) const PRODUCT_RETURN; 1886 void print_thread_state() const PRODUCT_RETURN; 1887 void print_on_error(outputStream* st, char* buf, int buflen) const; 1888 void print_name_on_error(outputStream* st, char* buf, int buflen) const; 1889 void verify(); 1890 const char* get_thread_name() const; 1891 protected: 1892 // factor out low-level mechanics for use in both normal and error cases 1893 virtual const char* get_thread_name_string(char* buf = NULL, int buflen = 0) const; 1894 public: 1895 const char* get_threadgroup_name() const; 1896 const char* get_parent_name() const; 1897 1898 // Accessing frames 1899 frame last_frame() { 1900 _anchor.make_walkable(this); 1901 return pd_last_frame(); 1902 } 1903 javaVFrame* last_java_vframe(RegisterMap* reg_map); 1904 1905 // Returns method at 'depth' java or native frames down the stack 1906 // Used for security checks 1907 Klass* security_get_caller_class(int depth); 1908 1909 // Print stack trace in external format 1910 void print_stack_on(outputStream* st); 1911 void print_stack() { print_stack_on(tty); } 1912 1913 // Print stack traces in various internal formats 1914 void trace_stack() PRODUCT_RETURN; 1915 void trace_stack_from(vframe* start_vf) PRODUCT_RETURN; 1916 void trace_frames() PRODUCT_RETURN; 1917 void trace_oops() PRODUCT_RETURN; 1918 1919 // Print an annotated view of the stack frames 1920 void print_frame_layout(int depth = 0, bool validate_only = false) NOT_DEBUG_RETURN; 1921 void validate_frame_layout() { 1922 print_frame_layout(0, true); 1923 } 1924 1925 // Returns the number of stack frames on the stack 1926 int depth() const; 1927 1928 // Function for testing deoptimization 1929 void deoptimize(); 1930 void make_zombies(); 1931 1932 void deoptimized_wrt_marked_nmethods(); 1933 1934 public: 1935 // Returns the running thread as a JavaThread 1936 static inline JavaThread* current(); 1937 1938 // Returns the active Java thread. Do not use this if you know you are calling 1939 // from a JavaThread, as it's slower than JavaThread::current. If called from 1940 // the VMThread, it also returns the JavaThread that instigated the VMThread's 1941 // operation. You may not want that either. 1942 static JavaThread* active(); 1943 1944 inline CompilerThread* as_CompilerThread(); 1945 1946 protected: 1947 virtual void pre_run(); 1948 virtual void run(); 1949 void thread_main_inner(); 1950 virtual void post_run(); 1951 1952 1953 private: 1954 GrowableArray<oop>* _array_for_gc; 1955 public: 1956 1957 void register_array_for_gc(GrowableArray<oop>* array) { _array_for_gc = array; } 1958 1959 public: 1960 // Thread local information maintained by JVMTI. 1961 void set_jvmti_thread_state(JvmtiThreadState *value) { _jvmti_thread_state = value; } 1962 // A JvmtiThreadState is lazily allocated. This jvmti_thread_state() 1963 // getter is used to get this JavaThread's JvmtiThreadState if it has 1964 // one which means NULL can be returned. JvmtiThreadState::state_for() 1965 // is used to get the specified JavaThread's JvmtiThreadState if it has 1966 // one or it allocates a new JvmtiThreadState for the JavaThread and 1967 // returns it. JvmtiThreadState::state_for() will return NULL only if 1968 // the specified JavaThread is exiting. 1969 JvmtiThreadState *jvmti_thread_state() const { return _jvmti_thread_state; } 1970 static ByteSize jvmti_thread_state_offset() { return byte_offset_of(JavaThread, _jvmti_thread_state); } 1971 1972 // JVMTI PopFrame support 1973 // Setting and clearing popframe_condition 1974 // All of these enumerated values are bits. popframe_pending 1975 // indicates that a PopFrame() has been requested and not yet been 1976 // completed. popframe_processing indicates that that PopFrame() is in 1977 // the process of being completed. popframe_force_deopt_reexecution_bit 1978 // indicates that special handling is required when returning to a 1979 // deoptimized caller. 1980 enum PopCondition { 1981 popframe_inactive = 0x00, 1982 popframe_pending_bit = 0x01, 1983 popframe_processing_bit = 0x02, 1984 popframe_force_deopt_reexecution_bit = 0x04 1985 }; 1986 PopCondition popframe_condition() { return (PopCondition) _popframe_condition; } 1987 void set_popframe_condition(PopCondition c) { _popframe_condition = c; } 1988 void set_popframe_condition_bit(PopCondition c) { _popframe_condition |= c; } 1989 void clear_popframe_condition() { _popframe_condition = popframe_inactive; } 1990 static ByteSize popframe_condition_offset() { return byte_offset_of(JavaThread, _popframe_condition); } 1991 bool has_pending_popframe() { return (popframe_condition() & popframe_pending_bit) != 0; } 1992 bool popframe_forcing_deopt_reexecution() { return (popframe_condition() & popframe_force_deopt_reexecution_bit) != 0; } 1993 void clear_popframe_forcing_deopt_reexecution() { _popframe_condition &= ~popframe_force_deopt_reexecution_bit; } 1994 #ifdef CC_INTERP 1995 bool pop_frame_pending(void) { return ((_popframe_condition & popframe_pending_bit) != 0); } 1996 void clr_pop_frame_pending(void) { _popframe_condition = popframe_inactive; } 1997 bool pop_frame_in_process(void) { return ((_popframe_condition & popframe_processing_bit) != 0); } 1998 void set_pop_frame_in_process(void) { _popframe_condition |= popframe_processing_bit; } 1999 void clr_pop_frame_in_process(void) { _popframe_condition &= ~popframe_processing_bit; } 2000 #endif 2001 2002 int frames_to_pop_failed_realloc() const { return _frames_to_pop_failed_realloc; } 2003 void set_frames_to_pop_failed_realloc(int nb) { _frames_to_pop_failed_realloc = nb; } 2004 void dec_frames_to_pop_failed_realloc() { _frames_to_pop_failed_realloc--; } 2005 2006 private: 2007 // Saved incoming arguments to popped frame. 2008 // Used only when popped interpreted frame returns to deoptimized frame. 2009 void* _popframe_preserved_args; 2010 int _popframe_preserved_args_size; 2011 2012 public: 2013 void popframe_preserve_args(ByteSize size_in_bytes, void* start); 2014 void* popframe_preserved_args(); 2015 ByteSize popframe_preserved_args_size(); 2016 WordSize popframe_preserved_args_size_in_words(); 2017 void popframe_free_preserved_args(); 2018 2019 2020 private: 2021 JvmtiThreadState *_jvmti_thread_state; 2022 2023 // Used by the interpreter in fullspeed mode for frame pop, method 2024 // entry, method exit and single stepping support. This field is 2025 // only set to non-zero by the VM_EnterInterpOnlyMode VM operation. 2026 // It can be set to zero asynchronously (i.e., without a VM operation 2027 // or a lock) so we have to be very careful. 2028 int _interp_only_mode; 2029 2030 public: 2031 // used by the interpreter for fullspeed debugging support (see above) 2032 static ByteSize interp_only_mode_offset() { return byte_offset_of(JavaThread, _interp_only_mode); } 2033 bool is_interp_only_mode() { return (_interp_only_mode != 0); } 2034 int get_interp_only_mode() { return _interp_only_mode; } 2035 void increment_interp_only_mode() { ++_interp_only_mode; } 2036 void decrement_interp_only_mode() { --_interp_only_mode; } 2037 2038 // support for cached flag that indicates whether exceptions need to be posted for this thread 2039 // if this is false, we can avoid deoptimizing when events are thrown 2040 // this gets set to reflect whether jvmtiExport::post_exception_throw would actually do anything 2041 private: 2042 int _should_post_on_exceptions_flag; 2043 2044 public: 2045 int should_post_on_exceptions_flag() { return _should_post_on_exceptions_flag; } 2046 void set_should_post_on_exceptions_flag(int val) { _should_post_on_exceptions_flag = val; } 2047 2048 private: 2049 ThreadStatistics *_thread_stat; 2050 2051 public: 2052 ThreadStatistics* get_thread_stat() const { return _thread_stat; } 2053 2054 // Return a blocker object for which this thread is blocked parking. 2055 oop current_park_blocker(); 2056 2057 private: 2058 static size_t _stack_size_at_create; 2059 2060 public: 2061 static inline size_t stack_size_at_create(void) { 2062 return _stack_size_at_create; 2063 } 2064 static inline void set_stack_size_at_create(size_t value) { 2065 _stack_size_at_create = value; 2066 } 2067 2068 // Machine dependent stuff 2069 #include OS_CPU_HEADER(thread) 2070 2071 public: 2072 void set_blocked_on_compilation(bool value) { 2073 _blocked_on_compilation = value; 2074 } 2075 2076 bool blocked_on_compilation() { 2077 return _blocked_on_compilation; 2078 } 2079 protected: 2080 bool _blocked_on_compilation; 2081 2082 2083 // JSR166 per-thread parker 2084 private: 2085 Parker* _parker; 2086 public: 2087 Parker* parker() { return _parker; } 2088 2089 // Biased locking support 2090 private: 2091 GrowableArray<MonitorInfo*>* _cached_monitor_info; 2092 public: 2093 GrowableArray<MonitorInfo*>* cached_monitor_info() { return _cached_monitor_info; } 2094 void set_cached_monitor_info(GrowableArray<MonitorInfo*>* info) { _cached_monitor_info = info; } 2095 2096 // clearing/querying jni attach status 2097 bool is_attaching_via_jni() const { return _jni_attach_state == _attaching_via_jni; } 2098 bool has_attached_via_jni() const { return is_attaching_via_jni() || _jni_attach_state == _attached_via_jni; } 2099 inline void set_done_attaching_via_jni(); 2100 }; 2101 2102 // Inline implementation of JavaThread::current 2103 inline JavaThread* JavaThread::current() { 2104 Thread* thread = Thread::current(); 2105 assert(thread->is_Java_thread(), "just checking"); 2106 return (JavaThread*)thread; 2107 } 2108 2109 inline CompilerThread* JavaThread::as_CompilerThread() { 2110 assert(is_Compiler_thread(), "just checking"); 2111 return (CompilerThread*)this; 2112 } 2113 2114 // Dedicated thread to sweep the code cache 2115 class CodeCacheSweeperThread : public JavaThread { 2116 CompiledMethod* _scanned_compiled_method; // nmethod being scanned by the sweeper 2117 public: 2118 CodeCacheSweeperThread(); 2119 // Track the nmethod currently being scanned by the sweeper 2120 void set_scanned_compiled_method(CompiledMethod* cm) { 2121 assert(_scanned_compiled_method == NULL || cm == NULL, "should reset to NULL before writing a new value"); 2122 _scanned_compiled_method = cm; 2123 } 2124 2125 // Hide sweeper thread from external view. 2126 bool is_hidden_from_external_view() const { return true; } 2127 2128 bool is_Code_cache_sweeper_thread() const { return true; } 2129 2130 // Prevent GC from unloading _scanned_compiled_method 2131 void oops_do(OopClosure* f, CodeBlobClosure* cf); 2132 void nmethods_do(CodeBlobClosure* cf); 2133 }; 2134 2135 // A thread used for Compilation. 2136 class CompilerThread : public JavaThread { 2137 friend class VMStructs; 2138 private: 2139 CompilerCounters* _counters; 2140 2141 ciEnv* _env; 2142 CompileLog* _log; 2143 CompileTask* volatile _task; // print_threads_compiling can read this concurrently. 2144 CompileQueue* _queue; 2145 BufferBlob* _buffer_blob; 2146 2147 AbstractCompiler* _compiler; 2148 TimeStamp _idle_time; 2149 2150 public: 2151 2152 static CompilerThread* current(); 2153 2154 CompilerThread(CompileQueue* queue, CompilerCounters* counters); 2155 ~CompilerThread(); 2156 2157 bool is_Compiler_thread() const { return true; } 2158 2159 virtual bool can_call_java() const; 2160 2161 // Hide native compiler threads from external view. 2162 bool is_hidden_from_external_view() const { return !can_call_java(); } 2163 2164 void set_compiler(AbstractCompiler* c) { _compiler = c; } 2165 AbstractCompiler* compiler() const { return _compiler; } 2166 2167 CompileQueue* queue() const { return _queue; } 2168 CompilerCounters* counters() const { return _counters; } 2169 2170 // Get/set the thread's compilation environment. 2171 ciEnv* env() { return _env; } 2172 void set_env(ciEnv* env) { _env = env; } 2173 2174 BufferBlob* get_buffer_blob() const { return _buffer_blob; } 2175 void set_buffer_blob(BufferBlob* b) { _buffer_blob = b; } 2176 2177 // Get/set the thread's logging information 2178 CompileLog* log() { return _log; } 2179 void init_log(CompileLog* log) { 2180 // Set once, for good. 2181 assert(_log == NULL, "set only once"); 2182 _log = log; 2183 } 2184 2185 void start_idle_timer() { _idle_time.update(); } 2186 jlong idle_time_millis() { 2187 return TimeHelper::counter_to_millis(_idle_time.ticks_since_update()); 2188 } 2189 2190 #ifndef PRODUCT 2191 private: 2192 IdealGraphPrinter *_ideal_graph_printer; 2193 public: 2194 IdealGraphPrinter *ideal_graph_printer() { return _ideal_graph_printer; } 2195 void set_ideal_graph_printer(IdealGraphPrinter *n) { _ideal_graph_printer = n; } 2196 #endif 2197 2198 // Get/set the thread's current task 2199 CompileTask* task() { return _task; } 2200 void set_task(CompileTask* task) { _task = task; } 2201 }; 2202 2203 inline CompilerThread* CompilerThread::current() { 2204 return JavaThread::current()->as_CompilerThread(); 2205 } 2206 2207 // The active thread queue. It also keeps track of the current used 2208 // thread priorities. 2209 class Threads: AllStatic { 2210 friend class VMStructs; 2211 private: 2212 static JavaThread* _thread_list; 2213 static int _number_of_threads; 2214 static int _number_of_non_daemon_threads; 2215 static int _return_code; 2216 static int _thread_claim_parity; 2217 #ifdef ASSERT 2218 static bool _vm_complete; 2219 #endif 2220 2221 static void initialize_java_lang_classes(JavaThread* main_thread, TRAPS); 2222 static void initialize_jsr292_core_classes(TRAPS); 2223 2224 public: 2225 // Thread management 2226 // force_daemon is a concession to JNI, where we may need to add a 2227 // thread to the thread list before allocating its thread object 2228 static void add(JavaThread* p, bool force_daemon = false); 2229 static void remove(JavaThread* p); 2230 static void non_java_threads_do(ThreadClosure* tc); 2231 static void java_threads_do(ThreadClosure* tc); 2232 static void java_threads_and_vm_thread_do(ThreadClosure* tc); 2233 static void threads_do(ThreadClosure* tc); 2234 static void possibly_parallel_threads_do(bool is_par, ThreadClosure* tc); 2235 2236 // Initializes the vm and creates the vm thread 2237 static jint create_vm(JavaVMInitArgs* args, bool* canTryAgain); 2238 static void convert_vm_init_libraries_to_agents(); 2239 static void create_vm_init_libraries(); 2240 static void create_vm_init_agents(); 2241 static void shutdown_vm_agents(); 2242 static bool destroy_vm(); 2243 // Supported VM versions via JNI 2244 // Includes JNI_VERSION_1_1 2245 static jboolean is_supported_jni_version_including_1_1(jint version); 2246 // Does not include JNI_VERSION_1_1 2247 static jboolean is_supported_jni_version(jint version); 2248 2249 // The "thread claim parity" provides a way for threads to be claimed 2250 // by parallel worker tasks. 2251 // 2252 // Each thread contains a a "parity" field. A task will claim the 2253 // thread only if its parity field is the same as the global parity, 2254 // which is updated by calling change_thread_claim_parity(). 2255 // 2256 // For this to work change_thread_claim_parity() needs to be called 2257 // exactly once in sequential code before starting parallel tasks 2258 // that should claim threads. 2259 // 2260 // New threads get their parity set to 0 and change_thread_claim_parity() 2261 // never set the global parity to 0. 2262 static int thread_claim_parity() { return _thread_claim_parity; } 2263 static void change_thread_claim_parity(); 2264 static void assert_all_threads_claimed() NOT_DEBUG_RETURN; 2265 2266 // Apply "f->do_oop" to all root oops in all threads. 2267 // This version may only be called by sequential code. 2268 static void oops_do(OopClosure* f, CodeBlobClosure* cf); 2269 // This version may be called by sequential or parallel code. 2270 static void possibly_parallel_oops_do(bool is_par, OopClosure* f, CodeBlobClosure* cf); 2271 2272 // Apply "f->do_oop" to roots in all threads that 2273 // are part of compiled frames 2274 static void compiled_frame_oops_do(OopClosure* f, CodeBlobClosure* cf); 2275 2276 static void convert_hcode_pointers(); 2277 static void restore_hcode_pointers(); 2278 2279 // Sweeper 2280 static void nmethods_do(CodeBlobClosure* cf); 2281 2282 // RedefineClasses support 2283 static void metadata_do(void f(Metadata*)); 2284 static void metadata_handles_do(void f(Metadata*)); 2285 2286 #ifdef ASSERT 2287 static bool is_vm_complete() { return _vm_complete; } 2288 #endif // ASSERT 2289 2290 // Verification 2291 static void verify(); 2292 static void print_on(outputStream* st, bool print_stacks, bool internal_format, bool print_concurrent_locks, bool print_extended_info); 2293 static void print(bool print_stacks, bool internal_format) { 2294 // this function is only used by debug.cpp 2295 print_on(tty, print_stacks, internal_format, false /* no concurrent lock printed */, false /* simple format */); 2296 } 2297 static void print_on_error(outputStream* st, Thread* current, char* buf, int buflen); 2298 static void print_on_error(Thread* this_thread, outputStream* st, Thread* current, char* buf, 2299 int buflen, bool* found_current); 2300 static void print_threads_compiling(outputStream* st, char* buf, int buflen); 2301 2302 // Get Java threads that are waiting to enter a monitor. 2303 static GrowableArray<JavaThread*>* get_pending_threads(ThreadsList * t_list, 2304 int count, address monitor); 2305 2306 // Get owning Java thread from the monitor's owner field. 2307 static JavaThread *owning_thread_from_monitor_owner(ThreadsList * t_list, 2308 address owner); 2309 2310 // Number of threads on the active threads list 2311 static int number_of_threads() { return _number_of_threads; } 2312 // Number of non-daemon threads on the active threads list 2313 static int number_of_non_daemon_threads() { return _number_of_non_daemon_threads; } 2314 2315 // Deoptimizes all frames tied to marked nmethods 2316 static void deoptimized_wrt_marked_nmethods(); 2317 }; 2318 2319 2320 // Thread iterator 2321 class ThreadClosure: public StackObj { 2322 public: 2323 virtual void do_thread(Thread* thread) = 0; 2324 }; 2325 2326 class SignalHandlerMark: public StackObj { 2327 private: 2328 Thread* _thread; 2329 public: 2330 SignalHandlerMark(Thread* t) { 2331 _thread = t; 2332 if (_thread) _thread->enter_signal_handler(); 2333 } 2334 ~SignalHandlerMark() { 2335 if (_thread) _thread->leave_signal_handler(); 2336 _thread = NULL; 2337 } 2338 }; 2339 2340 2341 #endif // SHARE_VM_RUNTIME_THREAD_HPP