1 /* 2 * Copyright (c) 1997, 2020, 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_RUNTIME_THREAD_HPP 26 #define SHARE_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/globalDefinitions.hpp" 52 #include "utilities/macros.hpp" 53 #ifdef ZERO 54 # include "stack_zero.hpp" 55 #endif 56 #if INCLUDE_JFR 57 #include "jfr/support/jfrThreadExtension.hpp" 58 #endif 59 60 61 class SafeThreadsListPtr; 62 class ThreadSafepointState; 63 class ThreadsList; 64 class ThreadsSMRSupport; 65 66 class JvmtiRawMonitor; 67 class JvmtiThreadState; 68 class ThreadStatistics; 69 class ConcurrentLocksDump; 70 class ParkEvent; 71 class Parker; 72 class MonitorInfo; 73 74 class ciEnv; 75 class CompileThread; 76 class CompileLog; 77 class CompileTask; 78 class CompileQueue; 79 class CompilerCounters; 80 81 class vframeArray; 82 class vframe; 83 class javaVFrame; 84 85 class DeoptResourceMark; 86 class jvmtiDeferredLocalVariableSet; 87 88 class ThreadClosure; 89 class ICRefillVerifier; 90 class IdealGraphPrinter; 91 92 class JVMCIEnv; 93 class JVMCIPrimitiveArray; 94 95 class Metadata; 96 class ResourceArea; 97 98 DEBUG_ONLY(class ResourceMark;) 99 100 class WorkerThread; 101 102 // Class hierarchy 103 // - Thread 104 // - JavaThread 105 // - various subclasses eg CompilerThread, ServiceThread 106 // - NonJavaThread 107 // - NamedThread 108 // - VMThread 109 // - ConcurrentGCThread 110 // - WorkerThread 111 // - GangWorker 112 // - WatcherThread 113 // - JfrThreadSampler 114 // 115 // All Thread subclasses must be either JavaThread or NonJavaThread. 116 // This means !t->is_Java_thread() iff t is a NonJavaThread, or t is 117 // a partially constructed/destroyed Thread. 118 119 // Thread execution sequence and actions: 120 // All threads: 121 // - thread_native_entry // per-OS native entry point 122 // - stack initialization 123 // - other OS-level initialization (signal masks etc) 124 // - handshake with creating thread (if not started suspended) 125 // - this->call_run() // common shared entry point 126 // - shared common initialization 127 // - this->pre_run() // virtual per-thread-type initialization 128 // - this->run() // virtual per-thread-type "main" logic 129 // - shared common tear-down 130 // - this->post_run() // virtual per-thread-type tear-down 131 // - // 'this' no longer referenceable 132 // - OS-level tear-down (minimal) 133 // - final logging 134 // 135 // For JavaThread: 136 // - this->run() // virtual but not normally overridden 137 // - this->thread_main_inner() // extra call level to ensure correct stack calculations 138 // - this->entry_point() // set differently for each kind of JavaThread 139 140 class Thread: public ThreadShadow { 141 friend class VMStructs; 142 friend class JVMCIVMStructs; 143 private: 144 145 #ifndef USE_LIBRARY_BASED_TLS_ONLY 146 // Current thread is maintained as a thread-local variable 147 static THREAD_LOCAL Thread* _thr_current; 148 #endif 149 150 // Thread local data area available to the GC. The internal 151 // structure and contents of this data area is GC-specific. 152 // Only GC and GC barrier code should access this data area. 153 GCThreadLocalData _gc_data; 154 155 public: 156 static ByteSize gc_data_offset() { 157 return byte_offset_of(Thread, _gc_data); 158 } 159 160 template <typename T> T* gc_data() { 161 STATIC_ASSERT(sizeof(T) <= sizeof(_gc_data)); 162 return reinterpret_cast<T*>(&_gc_data); 163 } 164 165 // Exception handling 166 // (Note: _pending_exception and friends are in ThreadShadow) 167 //oop _pending_exception; // pending exception for current thread 168 // const char* _exception_file; // file information for exception (debugging only) 169 // int _exception_line; // line information for exception (debugging only) 170 protected: 171 172 DEBUG_ONLY(static Thread* _starting_thread;) 173 174 // Support for forcing alignment of thread objects for biased locking 175 void* _real_malloc_address; 176 177 // JavaThread lifecycle support: 178 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 179 friend class ScanHazardPtrGatherProtectedThreadsClosure; // for cmpxchg_threads_hazard_ptr(), get_threads_hazard_ptr(), is_hazard_ptr_tagged() access 180 friend class ScanHazardPtrGatherThreadsListClosure; // for get_threads_hazard_ptr(), untag_hazard_ptr() access 181 friend class ScanHazardPtrPrintMatchingThreadsClosure; // for get_threads_hazard_ptr(), is_hazard_ptr_tagged() access 182 friend class ThreadsSMRSupport; // for _nested_threads_hazard_ptr_cnt, _threads_hazard_ptr, _threads_list_ptr access 183 184 ThreadsList* volatile _threads_hazard_ptr; 185 SafeThreadsListPtr* _threads_list_ptr; 186 ThreadsList* cmpxchg_threads_hazard_ptr(ThreadsList* exchange_value, ThreadsList* compare_value); 187 ThreadsList* get_threads_hazard_ptr(); 188 void set_threads_hazard_ptr(ThreadsList* new_list); 189 static bool is_hazard_ptr_tagged(ThreadsList* list) { 190 return (intptr_t(list) & intptr_t(1)) == intptr_t(1); 191 } 192 static ThreadsList* tag_hazard_ptr(ThreadsList* list) { 193 return (ThreadsList*)(intptr_t(list) | intptr_t(1)); 194 } 195 static ThreadsList* untag_hazard_ptr(ThreadsList* list) { 196 return (ThreadsList*)(intptr_t(list) & ~intptr_t(1)); 197 } 198 // This field is enabled via -XX:+EnableThreadSMRStatistics: 199 uint _nested_threads_hazard_ptr_cnt; 200 void dec_nested_threads_hazard_ptr_cnt() { 201 assert(_nested_threads_hazard_ptr_cnt != 0, "mismatched {dec,inc}_nested_threads_hazard_ptr_cnt()"); 202 _nested_threads_hazard_ptr_cnt--; 203 } 204 void inc_nested_threads_hazard_ptr_cnt() { 205 _nested_threads_hazard_ptr_cnt++; 206 } 207 uint nested_threads_hazard_ptr_cnt() { 208 return _nested_threads_hazard_ptr_cnt; 209 } 210 211 public: 212 void* operator new(size_t size) throw() { return allocate(size, true); } 213 void* operator new(size_t size, const std::nothrow_t& nothrow_constant) throw() { 214 return allocate(size, false); } 215 void operator delete(void* p); 216 217 protected: 218 static void* allocate(size_t size, bool throw_excpt, MEMFLAGS flags = mtThread); 219 private: 220 221 // *************************************************************** 222 // Suspend and resume support 223 // *************************************************************** 224 // 225 // VM suspend/resume no longer exists - it was once used for various 226 // things including safepoints but was deprecated and finally removed 227 // in Java 7. Because VM suspension was considered "internal" Java-level 228 // suspension was considered "external", and this legacy naming scheme 229 // remains. 230 // 231 // External suspend/resume requests come from JVM_SuspendThread, 232 // JVM_ResumeThread, JVMTI SuspendThread, and finally JVMTI 233 // ResumeThread. External 234 // suspend requests cause _external_suspend to be set and external 235 // resume requests cause _external_suspend to be cleared. 236 // External suspend requests do not nest on top of other external 237 // suspend requests. The higher level APIs reject suspend requests 238 // for already suspended threads. 239 // 240 // The external_suspend 241 // flag is checked by has_special_runtime_exit_condition() and java thread 242 // will self-suspend when handle_special_runtime_exit_condition() is 243 // called. Most uses of the _thread_blocked state in JavaThreads are 244 // considered the same as being externally suspended; if the blocking 245 // condition lifts, the JavaThread will self-suspend. Other places 246 // where VM checks for external_suspend include: 247 // + mutex granting (do not enter monitors when thread is suspended) 248 // + state transitions from _thread_in_native 249 // 250 // In general, java_suspend() does not wait for an external suspend 251 // request to complete. When it returns, the only guarantee is that 252 // the _external_suspend field is true. 253 // 254 // wait_for_ext_suspend_completion() is used to wait for an external 255 // suspend request to complete. External suspend requests are usually 256 // followed by some other interface call that requires the thread to 257 // be quiescent, e.g., GetCallTrace(). By moving the "wait time" into 258 // the interface that requires quiescence, we give the JavaThread a 259 // chance to self-suspend before we need it to be quiescent. This 260 // improves overall suspend/query performance. 261 // 262 // _suspend_flags controls the behavior of java_ suspend/resume. 263 // It must be set under the protection of SR_lock. Read from the flag is 264 // OK without SR_lock as long as the value is only used as a hint. 265 // (e.g., check _external_suspend first without lock and then recheck 266 // inside SR_lock and finish the suspension) 267 // 268 // _suspend_flags is also overloaded for other "special conditions" so 269 // that a single check indicates whether any special action is needed 270 // eg. for async exceptions. 271 // ------------------------------------------------------------------- 272 // Notes: 273 // 1. The suspend/resume logic no longer uses ThreadState in OSThread 274 // but we still update its value to keep other part of the system (mainly 275 // JVMTI) happy. ThreadState is legacy code (see notes in 276 // osThread.hpp). 277 // 278 // 2. It would be more natural if set_external_suspend() is private and 279 // part of java_suspend(), but that probably would affect the suspend/query 280 // performance. Need more investigation on this. 281 282 // suspend/resume lock: used for self-suspend 283 Monitor* _SR_lock; 284 285 protected: 286 enum SuspendFlags { 287 // NOTE: avoid using the sign-bit as cc generates different test code 288 // when the sign-bit is used, and sometimes incorrectly - see CR 6398077 289 290 _external_suspend = 0x20000000U, // thread is asked to self suspend 291 _ext_suspended = 0x40000000U, // thread has self-suspended 292 293 _has_async_exception = 0x00000001U, // there is a pending async exception 294 _critical_native_unlock = 0x00000002U, // Must call back to unlock JNI critical lock 295 296 _trace_flag = 0x00000004U // call tracing backend 297 }; 298 299 // various suspension related flags - atomically updated 300 // overloaded for async exception checking in check_special_condition_for_native_trans. 301 volatile uint32_t _suspend_flags; 302 303 private: 304 int _num_nested_signal; 305 306 DEBUG_ONLY(bool _suspendible_thread;) 307 308 public: 309 void enter_signal_handler() { _num_nested_signal++; } 310 void leave_signal_handler() { _num_nested_signal--; } 311 bool is_inside_signal_handler() const { return _num_nested_signal > 0; } 312 313 // Determines if a heap allocation failure will be retried 314 // (e.g., by deoptimizing and re-executing in the interpreter). 315 // In this case, the failed allocation must raise 316 // Universe::out_of_memory_error_retry() and omit side effects 317 // such as JVMTI events and handling -XX:+HeapDumpOnOutOfMemoryError 318 // and -XX:OnOutOfMemoryError. 319 virtual bool in_retryable_allocation() const { return false; } 320 321 #ifdef ASSERT 322 void set_suspendible_thread() { 323 _suspendible_thread = true; 324 } 325 326 void clear_suspendible_thread() { 327 _suspendible_thread = false; 328 } 329 330 bool is_suspendible_thread() { return _suspendible_thread; } 331 #endif 332 333 private: 334 // Active_handles points to a block of handles 335 JNIHandleBlock* _active_handles; 336 337 // One-element thread local free list 338 JNIHandleBlock* _free_handle_block; 339 340 // Point to the last handle mark 341 HandleMark* _last_handle_mark; 342 343 // Claim value for parallel iteration over threads. 344 uintx _threads_do_token; 345 346 // Support for GlobalCounter 347 private: 348 volatile uintx _rcu_counter; 349 public: 350 volatile uintx* get_rcu_counter() { 351 return &_rcu_counter; 352 } 353 354 public: 355 void set_last_handle_mark(HandleMark* mark) { _last_handle_mark = mark; } 356 HandleMark* last_handle_mark() const { return _last_handle_mark; } 357 private: 358 359 #ifdef ASSERT 360 ICRefillVerifier* _missed_ic_stub_refill_verifier; 361 362 public: 363 ICRefillVerifier* missed_ic_stub_refill_verifier() { 364 return _missed_ic_stub_refill_verifier; 365 } 366 367 void set_missed_ic_stub_refill_verifier(ICRefillVerifier* verifier) { 368 _missed_ic_stub_refill_verifier = verifier; 369 } 370 #endif // ASSERT 371 372 private: 373 374 // Debug support for checking if code allows safepoints or not. 375 // Safepoints in the VM can happen because of allocation, invoking a VM operation, or blocking on 376 // mutex, or blocking on an object synchronizer (Java locking). 377 // If _no_safepoint_count is non-zero, then an assertion failure will happen in any of 378 // the above cases. 379 // 380 // The class NoSafepointVerifier is used to set this counter. 381 // 382 NOT_PRODUCT(int _no_safepoint_count;) // If 0, thread allow a safepoint to happen 383 384 private: 385 // Used by SkipGCALot class. 386 NOT_PRODUCT(bool _skip_gcalot;) // Should we elide gc-a-lot? 387 388 friend class GCLocker; 389 friend class NoSafepointVerifier; 390 friend class PauseNoSafepointVerifier; 391 392 volatile void* _polling_page; // Thread local polling page 393 394 ThreadLocalAllocBuffer _tlab; // Thread-local eden 395 jlong _allocated_bytes; // Cumulative number of bytes allocated on 396 // the Java heap 397 ThreadHeapSampler _heap_sampler; // For use when sampling the memory. 398 399 ThreadStatisticalInfo _statistical_info; // Statistics about the thread 400 401 JFR_ONLY(DEFINE_THREAD_LOCAL_FIELD_JFR;) // Thread-local data for jfr 402 403 int _vm_operation_started_count; // VM_Operation support 404 int _vm_operation_completed_count; // VM_Operation support 405 406 ObjectMonitor* _current_pending_monitor; // ObjectMonitor this thread 407 // is waiting to lock 408 bool _current_pending_monitor_is_from_java; // locking is from Java code 409 JvmtiRawMonitor* _current_pending_raw_monitor; // JvmtiRawMonitor this thread 410 // is waiting to lock 411 412 413 // ObjectMonitor on which this thread called Object.wait() 414 ObjectMonitor* _current_waiting_monitor; 415 416 // Per-thread ObjectMonitor lists: 417 public: 418 ObjectMonitor* om_free_list; // SLL of free ObjectMonitors 419 int om_free_count; // # on om_free_list 420 int om_free_provision; // # to try to allocate next 421 ObjectMonitor* om_in_use_list; // SLL of in-use ObjectMonitors 422 int om_in_use_count; // # on om_in_use_list 423 424 #ifdef ASSERT 425 private: 426 volatile uint64_t _visited_for_critical_count; 427 428 public: 429 void set_visited_for_critical_count(uint64_t safepoint_id) { 430 assert(_visited_for_critical_count == 0, "Must be reset before set"); 431 assert((safepoint_id & 0x1) == 1, "Must be odd"); 432 _visited_for_critical_count = safepoint_id; 433 } 434 void reset_visited_for_critical_count(uint64_t safepoint_id) { 435 assert(_visited_for_critical_count == safepoint_id, "Was not visited"); 436 _visited_for_critical_count = 0; 437 } 438 bool was_visited_for_critical_count(uint64_t safepoint_id) const { 439 return _visited_for_critical_count == safepoint_id; 440 } 441 #endif 442 443 public: 444 enum { 445 is_definitely_current_thread = true 446 }; 447 448 // Constructor 449 Thread(); 450 virtual ~Thread() = 0; // Thread is abstract. 451 452 // Manage Thread::current() 453 void initialize_thread_current(); 454 static void clear_thread_current(); // TLS cleanup needed before threads terminate 455 456 protected: 457 // To be implemented by children. 458 virtual void run() = 0; 459 virtual void pre_run() = 0; 460 virtual void post_run() = 0; // Note: Thread must not be deleted prior to calling this! 461 462 #ifdef ASSERT 463 enum RunState { 464 PRE_CALL_RUN, 465 CALL_RUN, 466 PRE_RUN, 467 RUN, 468 POST_RUN 469 // POST_CALL_RUN - can't define this one as 'this' may be deleted when we want to set it 470 }; 471 RunState _run_state; // for lifecycle checks 472 #endif 473 474 475 public: 476 // invokes <ChildThreadClass>::run(), with common preparations and cleanups. 477 void call_run(); 478 479 // Testers 480 virtual bool is_VM_thread() const { return false; } 481 virtual bool is_Java_thread() const { return false; } 482 virtual bool is_Compiler_thread() const { return false; } 483 virtual bool is_Code_cache_sweeper_thread() const { return false; } 484 virtual bool is_service_thread() const { return false; } 485 virtual bool is_hidden_from_external_view() const { return false; } 486 virtual bool is_jvmti_agent_thread() const { return false; } 487 // True iff the thread can perform GC operations at a safepoint. 488 // Generally will be true only of VM thread and parallel GC WorkGang 489 // threads. 490 virtual bool is_GC_task_thread() const { return false; } 491 virtual bool is_Watcher_thread() const { return false; } 492 virtual bool is_ConcurrentGC_thread() const { return false; } 493 virtual bool is_Named_thread() const { return false; } 494 virtual bool is_Worker_thread() const { return false; } 495 496 // Can this thread make Java upcalls 497 virtual bool can_call_java() const { return false; } 498 499 // Is this a JavaThread that is on the VM's current ThreadsList? 500 // If so it must participate in the safepoint protocol. 501 virtual bool is_active_Java_thread() const { return false; } 502 503 // Casts 504 virtual WorkerThread* as_Worker_thread() const { return NULL; } 505 506 virtual char* name() const { return (char*)"Unknown thread"; } 507 508 // Returns the current thread (ASSERTS if NULL) 509 static inline Thread* current(); 510 // Returns the current thread, or NULL if not attached 511 static inline Thread* current_or_null(); 512 // Returns the current thread, or NULL if not attached, and is 513 // safe for use from signal-handlers 514 static inline Thread* current_or_null_safe(); 515 516 // Common thread operations 517 #ifdef ASSERT 518 static void check_for_dangling_thread_pointer(Thread *thread); 519 #endif 520 static void set_priority(Thread* thread, ThreadPriority priority); 521 static ThreadPriority get_priority(const Thread* const thread); 522 static void start(Thread* thread); 523 524 void set_native_thread_name(const char *name) { 525 assert(Thread::current() == this, "set_native_thread_name can only be called on the current thread"); 526 os::set_native_thread_name(name); 527 } 528 529 ObjectMonitor** om_in_use_list_addr() { return (ObjectMonitor **)&om_in_use_list; } 530 Monitor* SR_lock() const { return _SR_lock; } 531 532 bool has_async_exception() const { return (_suspend_flags & _has_async_exception) != 0; } 533 534 inline void set_suspend_flag(SuspendFlags f); 535 inline void clear_suspend_flag(SuspendFlags f); 536 537 inline void set_has_async_exception(); 538 inline void clear_has_async_exception(); 539 540 bool do_critical_native_unlock() const { return (_suspend_flags & _critical_native_unlock) != 0; } 541 542 inline void set_critical_native_unlock(); 543 inline void clear_critical_native_unlock(); 544 545 inline void set_trace_flag(); 546 inline void clear_trace_flag(); 547 548 // Support for Unhandled Oop detection 549 // Add the field for both, fastdebug and debug, builds to keep 550 // Thread's fields layout the same. 551 // Note: CHECK_UNHANDLED_OOPS is defined only for fastdebug build. 552 #ifdef CHECK_UNHANDLED_OOPS 553 private: 554 UnhandledOops* _unhandled_oops; 555 #elif defined(ASSERT) 556 private: 557 void* _unhandled_oops; 558 #endif 559 #ifdef CHECK_UNHANDLED_OOPS 560 public: 561 UnhandledOops* unhandled_oops() { return _unhandled_oops; } 562 // Mark oop safe for gc. It may be stack allocated but won't move. 563 void allow_unhandled_oop(oop *op) { 564 if (CheckUnhandledOops) unhandled_oops()->allow_unhandled_oop(op); 565 } 566 // Clear oops at safepoint so crashes point to unhandled oop violator 567 void clear_unhandled_oops() { 568 if (CheckUnhandledOops) unhandled_oops()->clear_unhandled_oops(); 569 } 570 #endif // CHECK_UNHANDLED_OOPS 571 572 public: 573 #ifndef PRODUCT 574 bool skip_gcalot() { return _skip_gcalot; } 575 void set_skip_gcalot(bool v) { _skip_gcalot = v; } 576 #endif 577 578 // Installs a pending exception to be inserted later 579 static void send_async_exception(oop thread_oop, oop java_throwable); 580 581 // Resource area 582 ResourceArea* resource_area() const { return _resource_area; } 583 void set_resource_area(ResourceArea* area) { _resource_area = area; } 584 585 OSThread* osthread() const { return _osthread; } 586 void set_osthread(OSThread* thread) { _osthread = thread; } 587 588 // JNI handle support 589 JNIHandleBlock* active_handles() const { return _active_handles; } 590 void set_active_handles(JNIHandleBlock* block) { _active_handles = block; } 591 JNIHandleBlock* free_handle_block() const { return _free_handle_block; } 592 void set_free_handle_block(JNIHandleBlock* block) { _free_handle_block = block; } 593 594 // Internal handle support 595 HandleArea* handle_area() const { return _handle_area; } 596 void set_handle_area(HandleArea* area) { _handle_area = area; } 597 598 GrowableArray<Metadata*>* metadata_handles() const { return _metadata_handles; } 599 void set_metadata_handles(GrowableArray<Metadata*>* handles){ _metadata_handles = handles; } 600 601 // Thread-Local Allocation Buffer (TLAB) support 602 ThreadLocalAllocBuffer& tlab() { return _tlab; } 603 void initialize_tlab() { 604 if (UseTLAB) { 605 tlab().initialize(); 606 } 607 } 608 609 jlong allocated_bytes() { return _allocated_bytes; } 610 void set_allocated_bytes(jlong value) { _allocated_bytes = value; } 611 void incr_allocated_bytes(jlong size) { _allocated_bytes += size; } 612 inline jlong cooked_allocated_bytes(); 613 614 ThreadHeapSampler& heap_sampler() { return _heap_sampler; } 615 616 ThreadStatisticalInfo& statistical_info() { return _statistical_info; } 617 618 JFR_ONLY(DEFINE_THREAD_LOCAL_ACCESSOR_JFR;) 619 620 bool is_trace_suspend() { return (_suspend_flags & _trace_flag) != 0; } 621 622 // VM operation support 623 int vm_operation_ticket() { return ++_vm_operation_started_count; } 624 int vm_operation_completed_count() { return _vm_operation_completed_count; } 625 void increment_vm_operation_completed_count() { _vm_operation_completed_count++; } 626 627 // For tracking the heavyweight monitor the thread is pending on. 628 ObjectMonitor* current_pending_monitor() { 629 return _current_pending_monitor; 630 } 631 void set_current_pending_monitor(ObjectMonitor* monitor) { 632 _current_pending_monitor = monitor; 633 } 634 void set_current_pending_monitor_is_from_java(bool from_java) { 635 _current_pending_monitor_is_from_java = from_java; 636 } 637 bool current_pending_monitor_is_from_java() { 638 return _current_pending_monitor_is_from_java; 639 } 640 641 // For tracking the ObjectMonitor on which this thread called Object.wait() 642 ObjectMonitor* current_waiting_monitor() { 643 return _current_waiting_monitor; 644 } 645 void set_current_waiting_monitor(ObjectMonitor* monitor) { 646 _current_waiting_monitor = monitor; 647 } 648 649 // For tracking the Jvmti raw monitor the thread is pending on. 650 JvmtiRawMonitor* current_pending_raw_monitor() { 651 return _current_pending_raw_monitor; 652 } 653 void set_current_pending_raw_monitor(JvmtiRawMonitor* monitor) { 654 _current_pending_raw_monitor = monitor; 655 } 656 657 // GC support 658 // Apply "f->do_oop" to all root oops in "this". 659 // Used by JavaThread::oops_do. 660 // Apply "cf->do_code_blob" (if !NULL) to all code blobs active in frames 661 virtual void oops_do(OopClosure* f, CodeBlobClosure* cf); 662 663 // Handles the parallel case for claim_threads_do. 664 private: 665 bool claim_par_threads_do(uintx claim_token); 666 public: 667 // Requires that "claim_token" is that of the current iteration. 668 // If "is_par" is false, sets the token of "this" to 669 // "claim_token", and returns "true". If "is_par" is true, 670 // uses an atomic instruction to set the current thread's token to 671 // "claim_token", if it is not already. Returns "true" iff the 672 // calling thread does the update, this indicates that the calling thread 673 // has claimed the thread in the current iteration. 674 bool claim_threads_do(bool is_par, uintx claim_token) { 675 if (!is_par) { 676 _threads_do_token = claim_token; 677 return true; 678 } else { 679 return claim_par_threads_do(claim_token); 680 } 681 } 682 683 uintx threads_do_token() const { return _threads_do_token; } 684 685 // jvmtiRedefineClasses support 686 void metadata_handles_do(void f(Metadata*)); 687 688 // Used by fast lock support 689 virtual bool is_lock_owned(address adr) const; 690 691 // Check if address is in the stack of the thread (not just for locks). 692 // Warning: the method can only be used on the running thread 693 bool is_in_stack(address adr) const; 694 // Check if address is in the usable part of the stack (excludes protected 695 // guard pages) 696 bool is_in_usable_stack(address adr) const; 697 698 // Sets this thread as starting thread. Returns failure if thread 699 // creation fails due to lack of memory, too many threads etc. 700 bool set_as_starting_thread(); 701 702 protected: 703 // OS data associated with the thread 704 OSThread* _osthread; // Platform-specific thread information 705 706 // Thread local resource area for temporary allocation within the VM 707 ResourceArea* _resource_area; 708 709 DEBUG_ONLY(ResourceMark* _current_resource_mark;) 710 711 // Thread local handle area for allocation of handles within the VM 712 HandleArea* _handle_area; 713 GrowableArray<Metadata*>* _metadata_handles; 714 715 // Support for stack overflow handling, get_thread, etc. 716 address _stack_base; 717 size_t _stack_size; 718 int _lgrp_id; 719 720 volatile void** polling_page_addr() { return &_polling_page; } 721 722 public: 723 // Stack overflow support 724 address stack_base() const { assert(_stack_base != NULL,"Sanity check"); return _stack_base; } 725 void set_stack_base(address base) { _stack_base = base; } 726 size_t stack_size() const { return _stack_size; } 727 void set_stack_size(size_t size) { _stack_size = size; } 728 address stack_end() const { return stack_base() - stack_size(); } 729 void record_stack_base_and_size(); 730 void register_thread_stack_with_NMT() NOT_NMT_RETURN; 731 732 bool on_local_stack(address adr) const { 733 // QQQ this has knowledge of direction, ought to be a stack method 734 return (_stack_base > adr && adr >= stack_end()); 735 } 736 737 int lgrp_id() const { return _lgrp_id; } 738 void set_lgrp_id(int value) { _lgrp_id = value; } 739 740 // Printing 741 void print_on(outputStream* st, bool print_extended_info) const; 742 virtual void print_on(outputStream* st) const { print_on(st, false); } 743 void print() const; 744 virtual void print_on_error(outputStream* st, char* buf, int buflen) const; 745 void print_value_on(outputStream* st) const; 746 747 // Debug-only code 748 #ifdef ASSERT 749 private: 750 // Deadlock detection support for Mutex locks. List of locks own by thread. 751 Mutex* _owned_locks; 752 // Mutex::set_owner_implementation is the only place where _owned_locks is modified, 753 // thus the friendship 754 friend class Mutex; 755 friend class Monitor; 756 757 public: 758 void print_owned_locks_on(outputStream* st) const; 759 void print_owned_locks() const { print_owned_locks_on(tty); } 760 Mutex* owned_locks() const { return _owned_locks; } 761 bool owns_locks() const { return owned_locks() != NULL; } 762 763 // Deadlock detection 764 ResourceMark* current_resource_mark() { return _current_resource_mark; } 765 void set_current_resource_mark(ResourceMark* rm) { _current_resource_mark = rm; } 766 #endif // ASSERT 767 768 // These functions check conditions on a JavaThread before possibly going to a safepoint, 769 // including NoSafepointVerifier. 770 void check_for_valid_safepoint_state() NOT_DEBUG_RETURN; 771 void check_possible_safepoint() NOT_DEBUG_RETURN; 772 773 private: 774 volatile int _jvmti_env_iteration_count; 775 776 public: 777 void entering_jvmti_env_iteration() { ++_jvmti_env_iteration_count; } 778 void leaving_jvmti_env_iteration() { --_jvmti_env_iteration_count; } 779 bool is_inside_jvmti_env_iteration() { return _jvmti_env_iteration_count > 0; } 780 781 // Code generation 782 static ByteSize exception_file_offset() { return byte_offset_of(Thread, _exception_file); } 783 static ByteSize exception_line_offset() { return byte_offset_of(Thread, _exception_line); } 784 static ByteSize active_handles_offset() { return byte_offset_of(Thread, _active_handles); } 785 786 static ByteSize stack_base_offset() { return byte_offset_of(Thread, _stack_base); } 787 static ByteSize stack_size_offset() { return byte_offset_of(Thread, _stack_size); } 788 789 static ByteSize polling_page_offset() { return byte_offset_of(Thread, _polling_page); } 790 791 static ByteSize tlab_start_offset() { return byte_offset_of(Thread, _tlab) + ThreadLocalAllocBuffer::start_offset(); } 792 static ByteSize tlab_end_offset() { return byte_offset_of(Thread, _tlab) + ThreadLocalAllocBuffer::end_offset(); } 793 static ByteSize tlab_top_offset() { return byte_offset_of(Thread, _tlab) + ThreadLocalAllocBuffer::top_offset(); } 794 static ByteSize tlab_pf_top_offset() { return byte_offset_of(Thread, _tlab) + ThreadLocalAllocBuffer::pf_top_offset(); } 795 796 static ByteSize allocated_bytes_offset() { return byte_offset_of(Thread, _allocated_bytes); } 797 798 JFR_ONLY(DEFINE_THREAD_LOCAL_OFFSET_JFR;) 799 800 public: 801 volatile intptr_t _Stalled; 802 volatile int _TypeTag; 803 ParkEvent * _ParkEvent; // for Object monitors and JVMTI raw monitors 804 ParkEvent * _MuxEvent; // for low-level muxAcquire-muxRelease 805 int NativeSyncRecursion; // diagnostic 806 807 volatile int _OnTrap; // Resume-at IP delta 808 jint _hashStateW; // Marsaglia Shift-XOR thread-local RNG 809 jint _hashStateX; // thread-specific hashCode generator state 810 jint _hashStateY; 811 jint _hashStateZ; 812 813 // Low-level leaf-lock primitives used to implement synchronization 814 // and native monitor-mutex infrastructure. 815 // Not for general synchronization use. 816 static void SpinAcquire(volatile int * Lock, const char * Name); 817 static void SpinRelease(volatile int * Lock); 818 static void muxAcquire(volatile intptr_t * Lock, const char * Name); 819 static void muxRelease(volatile intptr_t * Lock); 820 }; 821 822 // Inline implementation of Thread::current() 823 inline Thread* Thread::current() { 824 Thread* current = current_or_null(); 825 assert(current != NULL, "Thread::current() called on detached thread"); 826 return current; 827 } 828 829 inline Thread* Thread::current_or_null() { 830 #ifndef USE_LIBRARY_BASED_TLS_ONLY 831 return _thr_current; 832 #else 833 if (ThreadLocalStorage::is_initialized()) { 834 return ThreadLocalStorage::thread(); 835 } 836 return NULL; 837 #endif 838 } 839 840 inline Thread* Thread::current_or_null_safe() { 841 if (ThreadLocalStorage::is_initialized()) { 842 return ThreadLocalStorage::thread(); 843 } 844 return NULL; 845 } 846 847 class NonJavaThread: public Thread { 848 friend class VMStructs; 849 850 NonJavaThread* volatile _next; 851 852 class List; 853 static List _the_list; 854 855 void add_to_the_list(); 856 void remove_from_the_list(); 857 858 protected: 859 virtual void pre_run(); 860 virtual void post_run(); 861 862 public: 863 NonJavaThread(); 864 ~NonJavaThread(); 865 866 class Iterator; 867 }; 868 869 // Provides iteration over the list of NonJavaThreads. 870 // List addition occurs in pre_run(), and removal occurs in post_run(), 871 // so that only live fully-initialized threads can be found in the list. 872 // Threads created after an iterator is constructed will not be visited 873 // by the iterator. The scope of an iterator is a critical section; there 874 // must be no safepoint checks in that scope. 875 class NonJavaThread::Iterator : public StackObj { 876 uint _protect_enter; 877 NonJavaThread* _current; 878 879 NONCOPYABLE(Iterator); 880 881 public: 882 Iterator(); 883 ~Iterator(); 884 885 bool end() const { return _current == NULL; } 886 NonJavaThread* current() const { return _current; } 887 void step(); 888 }; 889 890 // Name support for threads. non-JavaThread subclasses with multiple 891 // uniquely named instances should derive from this. 892 class NamedThread: public NonJavaThread { 893 friend class VMStructs; 894 enum { 895 max_name_len = 64 896 }; 897 private: 898 char* _name; 899 // log JavaThread being processed by oops_do 900 JavaThread* _processed_thread; 901 uint _gc_id; // The current GC id when a thread takes part in GC 902 903 public: 904 NamedThread(); 905 ~NamedThread(); 906 // May only be called once per thread. 907 void set_name(const char* format, ...) ATTRIBUTE_PRINTF(2, 3); 908 virtual bool is_Named_thread() const { return true; } 909 virtual char* name() const { return _name == NULL ? (char*)"Unknown Thread" : _name; } 910 JavaThread *processed_thread() { return _processed_thread; } 911 void set_processed_thread(JavaThread *thread) { _processed_thread = thread; } 912 virtual void print_on(outputStream* st) const; 913 914 void set_gc_id(uint gc_id) { _gc_id = gc_id; } 915 uint gc_id() { return _gc_id; } 916 }; 917 918 // Worker threads are named and have an id of an assigned work. 919 class WorkerThread: public NamedThread { 920 private: 921 uint _id; 922 public: 923 WorkerThread() : _id(0) { } 924 virtual bool is_Worker_thread() const { return true; } 925 926 virtual WorkerThread* as_Worker_thread() const { 927 assert(is_Worker_thread(), "Dubious cast to WorkerThread*?"); 928 return (WorkerThread*) this; 929 } 930 931 void set_id(uint work_id) { _id = work_id; } 932 uint id() const { return _id; } 933 }; 934 935 // A single WatcherThread is used for simulating timer interrupts. 936 class WatcherThread: public NonJavaThread { 937 friend class VMStructs; 938 protected: 939 virtual void run(); 940 941 private: 942 static WatcherThread* _watcher_thread; 943 944 static bool _startable; 945 // volatile due to at least one lock-free read 946 volatile static bool _should_terminate; 947 public: 948 enum SomeConstants { 949 delay_interval = 10 // interrupt delay in milliseconds 950 }; 951 952 // Constructor 953 WatcherThread(); 954 955 // No destruction allowed 956 ~WatcherThread() { 957 guarantee(false, "WatcherThread deletion must fix the race with VM termination"); 958 } 959 960 // Tester 961 bool is_Watcher_thread() const { return true; } 962 963 // Printing 964 char* name() const { return (char*)"VM Periodic Task Thread"; } 965 void print_on(outputStream* st) const; 966 void unpark(); 967 968 // Returns the single instance of WatcherThread 969 static WatcherThread* watcher_thread() { return _watcher_thread; } 970 971 // Create and start the single instance of WatcherThread, or stop it on shutdown 972 static void start(); 973 static void stop(); 974 // Only allow start once the VM is sufficiently initialized 975 // Otherwise the first task to enroll will trigger the start 976 static void make_startable(); 977 private: 978 int sleep() const; 979 }; 980 981 982 class CompilerThread; 983 984 typedef void (*ThreadFunction)(JavaThread*, TRAPS); 985 986 class JavaThread: public Thread { 987 friend class VMStructs; 988 friend class JVMCIVMStructs; 989 friend class WhiteBox; 990 private: 991 bool _on_thread_list; // Is set when this JavaThread is added to the Threads list 992 oop _threadObj; // The Java level thread object 993 994 #ifdef ASSERT 995 private: 996 int _java_call_counter; 997 998 public: 999 int java_call_counter() { return _java_call_counter; } 1000 void inc_java_call_counter() { _java_call_counter++; } 1001 void dec_java_call_counter() { 1002 assert(_java_call_counter > 0, "Invalid nesting of JavaCallWrapper"); 1003 _java_call_counter--; 1004 } 1005 private: // restore original namespace restriction 1006 #endif // ifdef ASSERT 1007 1008 #ifndef PRODUCT 1009 public: 1010 enum { 1011 jump_ring_buffer_size = 16 1012 }; 1013 private: // restore original namespace restriction 1014 #endif 1015 1016 JavaFrameAnchor _anchor; // Encapsulation of current java frame and it state 1017 1018 ThreadFunction _entry_point; 1019 1020 JNIEnv _jni_environment; 1021 1022 // Deopt support 1023 DeoptResourceMark* _deopt_mark; // Holds special ResourceMark for deoptimization 1024 1025 CompiledMethod* _deopt_nmethod; // CompiledMethod that is currently being deoptimized 1026 vframeArray* _vframe_array_head; // Holds the heap of the active vframeArrays 1027 vframeArray* _vframe_array_last; // Holds last vFrameArray we popped 1028 // Because deoptimization is lazy we must save jvmti requests to set locals 1029 // in compiled frames until we deoptimize and we have an interpreter frame. 1030 // This holds the pointer to array (yeah like there might be more than one) of 1031 // description of compiled vframes that have locals that need to be updated. 1032 GrowableArray<jvmtiDeferredLocalVariableSet*>* _deferred_locals_updates; 1033 1034 // Handshake value for fixing 6243940. We need a place for the i2c 1035 // adapter to store the callee Method*. This value is NEVER live 1036 // across a gc point so it does NOT have to be gc'd 1037 // The handshake is open ended since we can't be certain that it will 1038 // be NULLed. This is because we rarely ever see the race and end up 1039 // in handle_wrong_method which is the backend of the handshake. See 1040 // code in i2c adapters and handle_wrong_method. 1041 1042 Method* _callee_target; 1043 1044 // Used to pass back results to the interpreter or generated code running Java code. 1045 oop _vm_result; // oop result is GC-preserved 1046 Metadata* _vm_result_2; // non-oop result 1047 1048 // See ReduceInitialCardMarks: this holds the precise space interval of 1049 // the most recent slow path allocation for which compiled code has 1050 // elided card-marks for performance along the fast-path. 1051 MemRegion _deferred_card_mark; 1052 1053 MonitorChunk* _monitor_chunks; // Contains the off stack monitors 1054 // allocated during deoptimization 1055 // and by JNI_MonitorEnter/Exit 1056 1057 // Async. requests support 1058 enum AsyncRequests { 1059 _no_async_condition = 0, 1060 _async_exception, 1061 _async_unsafe_access_error 1062 }; 1063 AsyncRequests _special_runtime_exit_condition; // Enum indicating pending async. request 1064 oop _pending_async_exception; 1065 1066 // Safepoint support 1067 public: // Expose _thread_state for SafeFetchInt() 1068 volatile JavaThreadState _thread_state; 1069 private: 1070 ThreadSafepointState* _safepoint_state; // Holds information about a thread during a safepoint 1071 address _saved_exception_pc; // Saved pc of instruction where last implicit exception happened 1072 1073 // JavaThread termination support 1074 enum TerminatedTypes { 1075 _not_terminated = 0xDEAD - 2, 1076 _thread_exiting, // JavaThread::exit() has been called for this thread 1077 _thread_terminated, // JavaThread is removed from thread list 1078 _vm_exited // JavaThread is still executing native code, but VM is terminated 1079 // only VM_Exit can set _vm_exited 1080 }; 1081 1082 // In general a JavaThread's _terminated field transitions as follows: 1083 // 1084 // _not_terminated => _thread_exiting => _thread_terminated 1085 // 1086 // _vm_exited is a special value to cover the case of a JavaThread 1087 // executing native code after the VM itself is terminated. 1088 volatile TerminatedTypes _terminated; 1089 // suspend/resume support 1090 volatile bool _suspend_equivalent; // Suspend equivalent condition 1091 jint _in_deopt_handler; // count of deoptimization 1092 // handlers thread is in 1093 volatile bool _doing_unsafe_access; // Thread may fault due to unsafe access 1094 bool _do_not_unlock_if_synchronized; // Do not unlock the receiver of a synchronized method (since it was 1095 // never locked) when throwing an exception. Used by interpreter only. 1096 1097 // JNI attach states: 1098 enum JNIAttachStates { 1099 _not_attaching_via_jni = 1, // thread is not attaching via JNI 1100 _attaching_via_jni, // thread is attaching via JNI 1101 _attached_via_jni // thread has attached via JNI 1102 }; 1103 1104 // A regular JavaThread's _jni_attach_state is _not_attaching_via_jni. 1105 // A native thread that is attaching via JNI starts with a value 1106 // of _attaching_via_jni and transitions to _attached_via_jni. 1107 volatile JNIAttachStates _jni_attach_state; 1108 1109 public: 1110 // State of the stack guard pages for this thread. 1111 enum StackGuardState { 1112 stack_guard_unused, // not needed 1113 stack_guard_reserved_disabled, 1114 stack_guard_yellow_reserved_disabled,// disabled (temporarily) after stack overflow 1115 stack_guard_enabled // enabled 1116 }; 1117 1118 private: 1119 1120 #if INCLUDE_JVMCI 1121 // The _pending_* fields below are used to communicate extra information 1122 // from an uncommon trap in JVMCI compiled code to the uncommon trap handler. 1123 1124 // Communicates the DeoptReason and DeoptAction of the uncommon trap 1125 int _pending_deoptimization; 1126 1127 // Specifies whether the uncommon trap is to bci 0 of a synchronized method 1128 // before the monitor has been acquired. 1129 bool _pending_monitorenter; 1130 1131 // Specifies if the DeoptReason for the last uncommon trap was Reason_transfer_to_interpreter 1132 bool _pending_transfer_to_interpreter; 1133 1134 // True if in a runtime call from compiled code that will deoptimize 1135 // and re-execute a failed heap allocation in the interpreter. 1136 bool _in_retryable_allocation; 1137 1138 // An id of a speculation that JVMCI compiled code can use to further describe and 1139 // uniquely identify the speculative optimization guarded by the uncommon trap 1140 jlong _pending_failed_speculation; 1141 1142 // These fields are mutually exclusive in terms of live ranges. 1143 union { 1144 // Communicates the pc at which the most recent implicit exception occurred 1145 // from the signal handler to a deoptimization stub. 1146 address _implicit_exception_pc; 1147 1148 // Communicates an alternative call target to an i2c stub from a JavaCall . 1149 address _alternate_call_target; 1150 } _jvmci; 1151 1152 // Support for high precision, thread sensitive counters in JVMCI compiled code. 1153 jlong* _jvmci_counters; 1154 1155 public: 1156 static jlong* _jvmci_old_thread_counters; 1157 static void collect_counters(jlong* array, int length); 1158 void resize_counters(int current_size, int new_size); 1159 static void resize_all_jvmci_counters(int new_size); 1160 1161 private: 1162 #endif // INCLUDE_JVMCI 1163 1164 StackGuardState _stack_guard_state; 1165 1166 // Precompute the limit of the stack as used in stack overflow checks. 1167 // We load it from here to simplify the stack overflow check in assembly. 1168 address _stack_overflow_limit; 1169 address _reserved_stack_activation; 1170 1171 // Compiler exception handling (NOTE: The _exception_oop is *NOT* the same as _pending_exception. It is 1172 // used to temp. parsing values into and out of the runtime system during exception handling for compiled 1173 // code) 1174 volatile oop _exception_oop; // Exception thrown in compiled code 1175 volatile address _exception_pc; // PC where exception happened 1176 volatile address _exception_handler_pc; // PC for handler of exception 1177 volatile int _is_method_handle_return; // true (== 1) if the current exception PC is a MethodHandle call site. 1178 1179 private: 1180 // support for JNI critical regions 1181 jint _jni_active_critical; // count of entries into JNI critical region 1182 1183 // Checked JNI: function name requires exception check 1184 char* _pending_jni_exception_check_fn; 1185 1186 // For deadlock detection. 1187 int _depth_first_number; 1188 1189 // JVMTI PopFrame support 1190 // This is set to popframe_pending to signal that top Java frame should be popped immediately 1191 int _popframe_condition; 1192 1193 // If reallocation of scalar replaced objects fails, we throw OOM 1194 // and during exception propagation, pop the top 1195 // _frames_to_pop_failed_realloc frames, the ones that reference 1196 // failed reallocations. 1197 int _frames_to_pop_failed_realloc; 1198 1199 friend class VMThread; 1200 friend class ThreadWaitTransition; 1201 friend class VM_Exit; 1202 1203 void initialize(); // Initialized the instance variables 1204 1205 public: 1206 // Constructor 1207 JavaThread(bool is_attaching_via_jni = false); // for main thread and JNI attached threads 1208 JavaThread(ThreadFunction entry_point, size_t stack_size = 0); 1209 ~JavaThread(); 1210 1211 #ifdef ASSERT 1212 // verify this JavaThread hasn't be published in the Threads::list yet 1213 void verify_not_published(); 1214 #endif // ASSERT 1215 1216 //JNI functiontable getter/setter for JVMTI jni function table interception API. 1217 void set_jni_functions(struct JNINativeInterface_* functionTable) { 1218 _jni_environment.functions = functionTable; 1219 } 1220 struct JNINativeInterface_* get_jni_functions() { 1221 return (struct JNINativeInterface_ *)_jni_environment.functions; 1222 } 1223 1224 // This function is called at thread creation to allow 1225 // platform specific thread variables to be initialized. 1226 void cache_global_variables(); 1227 1228 // Executes Shutdown.shutdown() 1229 void invoke_shutdown_hooks(); 1230 1231 // Cleanup on thread exit 1232 enum ExitType { 1233 normal_exit, 1234 jni_detach 1235 }; 1236 void exit(bool destroy_vm, ExitType exit_type = normal_exit); 1237 1238 void cleanup_failed_attach_current_thread(bool is_daemon); 1239 1240 // Testers 1241 virtual bool is_Java_thread() const { return true; } 1242 virtual bool can_call_java() const { return true; } 1243 1244 virtual bool is_active_Java_thread() const { 1245 return on_thread_list() && !is_terminated(); 1246 } 1247 1248 // Thread oop. threadObj() can be NULL for initial JavaThread 1249 // (or for threads attached via JNI) 1250 oop threadObj() const { return _threadObj; } 1251 void set_threadObj(oop p) { _threadObj = p; } 1252 1253 // Prepare thread and add to priority queue. If a priority is 1254 // not specified, use the priority of the thread object. Threads_lock 1255 // must be held while this function is called. 1256 void prepare(jobject jni_thread, ThreadPriority prio=NoPriority); 1257 1258 void set_saved_exception_pc(address pc) { _saved_exception_pc = pc; } 1259 address saved_exception_pc() { return _saved_exception_pc; } 1260 1261 1262 ThreadFunction entry_point() const { return _entry_point; } 1263 1264 // Allocates a new Java level thread object for this thread. thread_name may be NULL. 1265 void allocate_threadObj(Handle thread_group, const char* thread_name, bool daemon, TRAPS); 1266 1267 // Last frame anchor routines 1268 1269 JavaFrameAnchor* frame_anchor(void) { return &_anchor; } 1270 1271 // last_Java_sp 1272 bool has_last_Java_frame() const { return _anchor.has_last_Java_frame(); } 1273 intptr_t* last_Java_sp() const { return _anchor.last_Java_sp(); } 1274 1275 // last_Java_pc 1276 1277 address last_Java_pc(void) { return _anchor.last_Java_pc(); } 1278 1279 // Safepoint support 1280 inline JavaThreadState thread_state() const; 1281 inline void set_thread_state(JavaThreadState s); 1282 inline void set_thread_state_fence(JavaThreadState s); // fence after setting thread state 1283 inline ThreadSafepointState* safepoint_state() const; 1284 inline void set_safepoint_state(ThreadSafepointState* state); 1285 inline bool is_at_poll_safepoint(); 1286 1287 // JavaThread termination and lifecycle support: 1288 void smr_delete(); 1289 bool on_thread_list() const { return _on_thread_list; } 1290 void set_on_thread_list() { _on_thread_list = true; } 1291 1292 // thread has called JavaThread::exit() or is terminated 1293 bool is_exiting() const; 1294 // thread is terminated (no longer on the threads list); we compare 1295 // against the two non-terminated values so that a freed JavaThread 1296 // will also be considered terminated. 1297 bool check_is_terminated(TerminatedTypes l_terminated) const { 1298 return l_terminated != _not_terminated && l_terminated != _thread_exiting; 1299 } 1300 bool is_terminated() const; 1301 void set_terminated(TerminatedTypes t); 1302 // special for Threads::remove() which is static: 1303 void set_terminated_value(); 1304 void block_if_vm_exited(); 1305 1306 bool doing_unsafe_access() { return _doing_unsafe_access; } 1307 void set_doing_unsafe_access(bool val) { _doing_unsafe_access = val; } 1308 1309 bool do_not_unlock_if_synchronized() { return _do_not_unlock_if_synchronized; } 1310 void set_do_not_unlock_if_synchronized(bool val) { _do_not_unlock_if_synchronized = val; } 1311 1312 inline void set_polling_page_release(void* poll_value); 1313 inline void set_polling_page(void* poll_value); 1314 inline volatile void* get_polling_page(); 1315 1316 private: 1317 // Support for thread handshake operations 1318 HandshakeState _handshake; 1319 public: 1320 void set_handshake_operation(HandshakeOperation* op) { 1321 _handshake.set_operation(op); 1322 } 1323 1324 bool has_handshake() const { 1325 return _handshake.has_operation(); 1326 } 1327 1328 void handshake_process_by_self() { 1329 _handshake.process_by_self(); 1330 } 1331 1332 bool handshake_try_process(HandshakeOperation* op) { 1333 return _handshake.try_process(op); 1334 } 1335 1336 #ifdef ASSERT 1337 Thread* get_active_handshaker() const { 1338 return _handshake.get_active_handshaker(); 1339 } 1340 #endif 1341 1342 // Suspend/resume support for JavaThread 1343 private: 1344 inline void set_ext_suspended(); 1345 inline void clear_ext_suspended(); 1346 1347 public: 1348 void java_suspend(); // higher-level suspension logic called by the public APIs 1349 void java_resume(); // higher-level resume logic called by the public APIs 1350 int java_suspend_self(); // low-level self-suspension mechanics 1351 1352 private: 1353 // mid-level wrapper around java_suspend_self to set up correct state and 1354 // check for a pending safepoint at the end 1355 void java_suspend_self_with_safepoint_check(); 1356 1357 public: 1358 void check_and_wait_while_suspended() { 1359 assert(JavaThread::current() == this, "sanity check"); 1360 1361 bool do_self_suspend; 1362 do { 1363 // were we externally suspended while we were waiting? 1364 do_self_suspend = handle_special_suspend_equivalent_condition(); 1365 if (do_self_suspend) { 1366 // don't surprise the thread that suspended us by returning 1367 java_suspend_self(); 1368 set_suspend_equivalent(); 1369 } 1370 } while (do_self_suspend); 1371 } 1372 static void check_safepoint_and_suspend_for_native_trans(JavaThread *thread); 1373 // Check for async exception in addition to safepoint and suspend request. 1374 static void check_special_condition_for_native_trans(JavaThread *thread); 1375 1376 // Same as check_special_condition_for_native_trans but finishes the 1377 // transition into thread_in_Java mode so that it can potentially 1378 // block. 1379 static void check_special_condition_for_native_trans_and_transition(JavaThread *thread); 1380 1381 bool is_ext_suspend_completed(bool called_by_wait, int delay, uint32_t *bits); 1382 bool is_ext_suspend_completed_with_lock(uint32_t *bits) { 1383 MutexLocker ml(SR_lock(), Mutex::_no_safepoint_check_flag); 1384 // Warning: is_ext_suspend_completed() may temporarily drop the 1385 // SR_lock to allow the thread to reach a stable thread state if 1386 // it is currently in a transient thread state. 1387 return is_ext_suspend_completed(false /* !called_by_wait */, 1388 SuspendRetryDelay, bits); 1389 } 1390 1391 // We cannot allow wait_for_ext_suspend_completion() to run forever or 1392 // we could hang. SuspendRetryCount and SuspendRetryDelay are normally 1393 // passed as the count and delay parameters. Experiments with specific 1394 // calls to wait_for_ext_suspend_completion() can be done by passing 1395 // other values in the code. Experiments with all calls can be done 1396 // via the appropriate -XX options. 1397 bool wait_for_ext_suspend_completion(int count, int delay, uint32_t *bits); 1398 1399 // test for suspend - most (all?) of these should go away 1400 bool is_thread_fully_suspended(bool wait_for_suspend, uint32_t *bits); 1401 1402 inline void set_external_suspend(); 1403 inline void clear_external_suspend(); 1404 1405 bool is_external_suspend() const { 1406 return (_suspend_flags & _external_suspend) != 0; 1407 } 1408 // Whenever a thread transitions from native to vm/java it must suspend 1409 // if external|deopt suspend is present. 1410 bool is_suspend_after_native() const { 1411 return (_suspend_flags & (_external_suspend JFR_ONLY(| _trace_flag))) != 0; 1412 } 1413 1414 // external suspend request is completed 1415 bool is_ext_suspended() const { 1416 return (_suspend_flags & _ext_suspended) != 0; 1417 } 1418 1419 bool is_external_suspend_with_lock() const { 1420 MutexLocker ml(SR_lock(), Mutex::_no_safepoint_check_flag); 1421 return is_external_suspend(); 1422 } 1423 1424 // Special method to handle a pending external suspend request 1425 // when a suspend equivalent condition lifts. 1426 bool handle_special_suspend_equivalent_condition() { 1427 assert(is_suspend_equivalent(), 1428 "should only be called in a suspend equivalence condition"); 1429 MutexLocker ml(SR_lock(), Mutex::_no_safepoint_check_flag); 1430 bool ret = is_external_suspend(); 1431 if (!ret) { 1432 // not about to self-suspend so clear suspend equivalence 1433 clear_suspend_equivalent(); 1434 } 1435 // implied else: 1436 // We have a pending external suspend request so we leave the 1437 // suspend_equivalent flag set until java_suspend_self() sets 1438 // the ext_suspended flag and clears the suspend_equivalent 1439 // flag. This insures that wait_for_ext_suspend_completion() 1440 // will return consistent values. 1441 return ret; 1442 } 1443 1444 // utility methods to see if we are doing some kind of suspension 1445 bool is_being_ext_suspended() const { 1446 MutexLocker ml(SR_lock(), Mutex::_no_safepoint_check_flag); 1447 return is_ext_suspended() || is_external_suspend(); 1448 } 1449 1450 bool is_suspend_equivalent() const { return _suspend_equivalent; } 1451 1452 void set_suspend_equivalent() { _suspend_equivalent = true; } 1453 void clear_suspend_equivalent() { _suspend_equivalent = false; } 1454 1455 // Thread.stop support 1456 void send_thread_stop(oop throwable); 1457 AsyncRequests clear_special_runtime_exit_condition() { 1458 AsyncRequests x = _special_runtime_exit_condition; 1459 _special_runtime_exit_condition = _no_async_condition; 1460 return x; 1461 } 1462 1463 // Are any async conditions present? 1464 bool has_async_condition() { return (_special_runtime_exit_condition != _no_async_condition); } 1465 1466 void check_and_handle_async_exceptions(bool check_unsafe_error = true); 1467 1468 // these next two are also used for self-suspension and async exception support 1469 void handle_special_runtime_exit_condition(bool check_asyncs = true); 1470 1471 // Return true if JavaThread has an asynchronous condition or 1472 // if external suspension is requested. 1473 bool has_special_runtime_exit_condition() { 1474 // Because we don't use is_external_suspend_with_lock 1475 // it is possible that we won't see an asynchronous external suspend 1476 // request that has just gotten started, i.e., SR_lock grabbed but 1477 // _external_suspend field change either not made yet or not visible 1478 // yet. However, this is okay because the request is asynchronous and 1479 // we will see the new flag value the next time through. It's also 1480 // possible that the external suspend request is dropped after 1481 // we have checked is_external_suspend(), we will recheck its value 1482 // under SR_lock in java_suspend_self(). 1483 return (_special_runtime_exit_condition != _no_async_condition) || 1484 is_external_suspend() || is_trace_suspend(); 1485 } 1486 1487 void set_pending_unsafe_access_error() { _special_runtime_exit_condition = _async_unsafe_access_error; } 1488 1489 inline void set_pending_async_exception(oop e); 1490 1491 // Fast-locking support 1492 bool is_lock_owned(address adr) const; 1493 1494 // Accessors for vframe array top 1495 // The linked list of vframe arrays are sorted on sp. This means when we 1496 // unpack the head must contain the vframe array to unpack. 1497 void set_vframe_array_head(vframeArray* value) { _vframe_array_head = value; } 1498 vframeArray* vframe_array_head() const { return _vframe_array_head; } 1499 1500 // Side structure for deferring update of java frame locals until deopt occurs 1501 GrowableArray<jvmtiDeferredLocalVariableSet*>* deferred_locals() const { return _deferred_locals_updates; } 1502 void set_deferred_locals(GrowableArray<jvmtiDeferredLocalVariableSet *>* vf) { _deferred_locals_updates = vf; } 1503 1504 // These only really exist to make debugging deopt problems simpler 1505 1506 void set_vframe_array_last(vframeArray* value) { _vframe_array_last = value; } 1507 vframeArray* vframe_array_last() const { return _vframe_array_last; } 1508 1509 // The special resourceMark used during deoptimization 1510 1511 void set_deopt_mark(DeoptResourceMark* value) { _deopt_mark = value; } 1512 DeoptResourceMark* deopt_mark(void) { return _deopt_mark; } 1513 1514 void set_deopt_compiled_method(CompiledMethod* nm) { _deopt_nmethod = nm; } 1515 CompiledMethod* deopt_compiled_method() { return _deopt_nmethod; } 1516 1517 Method* callee_target() const { return _callee_target; } 1518 void set_callee_target (Method* x) { _callee_target = x; } 1519 1520 // Oop results of vm runtime calls 1521 oop vm_result() const { return _vm_result; } 1522 void set_vm_result (oop x) { _vm_result = x; } 1523 1524 Metadata* vm_result_2() const { return _vm_result_2; } 1525 void set_vm_result_2 (Metadata* x) { _vm_result_2 = x; } 1526 1527 MemRegion deferred_card_mark() const { return _deferred_card_mark; } 1528 void set_deferred_card_mark(MemRegion mr) { _deferred_card_mark = mr; } 1529 1530 #if INCLUDE_JVMCI 1531 int pending_deoptimization() const { return _pending_deoptimization; } 1532 jlong pending_failed_speculation() const { return _pending_failed_speculation; } 1533 bool has_pending_monitorenter() const { return _pending_monitorenter; } 1534 void set_pending_monitorenter(bool b) { _pending_monitorenter = b; } 1535 void set_pending_deoptimization(int reason) { _pending_deoptimization = reason; } 1536 void set_pending_failed_speculation(jlong failed_speculation) { _pending_failed_speculation = failed_speculation; } 1537 void set_pending_transfer_to_interpreter(bool b) { _pending_transfer_to_interpreter = b; } 1538 void set_jvmci_alternate_call_target(address a) { assert(_jvmci._alternate_call_target == NULL, "must be"); _jvmci._alternate_call_target = a; } 1539 void set_jvmci_implicit_exception_pc(address a) { assert(_jvmci._implicit_exception_pc == NULL, "must be"); _jvmci._implicit_exception_pc = a; } 1540 1541 virtual bool in_retryable_allocation() const { return _in_retryable_allocation; } 1542 void set_in_retryable_allocation(bool b) { _in_retryable_allocation = b; } 1543 #endif // INCLUDE_JVMCI 1544 1545 // Exception handling for compiled methods 1546 oop exception_oop() const { return _exception_oop; } 1547 address exception_pc() const { return _exception_pc; } 1548 address exception_handler_pc() const { return _exception_handler_pc; } 1549 bool is_method_handle_return() const { return _is_method_handle_return == 1; } 1550 1551 void set_exception_oop(oop o) { (void)const_cast<oop&>(_exception_oop = o); } 1552 void set_exception_pc(address a) { _exception_pc = a; } 1553 void set_exception_handler_pc(address a) { _exception_handler_pc = a; } 1554 void set_is_method_handle_return(bool value) { _is_method_handle_return = value ? 1 : 0; } 1555 1556 void clear_exception_oop_and_pc() { 1557 set_exception_oop(NULL); 1558 set_exception_pc(NULL); 1559 } 1560 1561 // Stack overflow support 1562 // 1563 // (small addresses) 1564 // 1565 // -- <-- stack_end() --- 1566 // | | 1567 // | red pages | 1568 // | | 1569 // -- <-- stack_red_zone_base() | 1570 // | | 1571 // | guard 1572 // | yellow pages zone 1573 // | | 1574 // | | 1575 // -- <-- stack_yellow_zone_base() | 1576 // | | 1577 // | | 1578 // | reserved pages | 1579 // | | 1580 // -- <-- stack_reserved_zone_base() --- --- 1581 // /|\ shadow <-- stack_overflow_limit() (somewhere in here) 1582 // | zone 1583 // \|/ size 1584 // some untouched memory --- 1585 // 1586 // 1587 // -- 1588 // | 1589 // | shadow zone 1590 // | 1591 // -- 1592 // x frame n 1593 // -- 1594 // x frame n-1 1595 // x 1596 // -- 1597 // ... 1598 // 1599 // -- 1600 // x frame 0 1601 // -- <-- stack_base() 1602 // 1603 // (large addresses) 1604 // 1605 1606 private: 1607 // These values are derived from flags StackRedPages, StackYellowPages, 1608 // StackReservedPages and StackShadowPages. The zone size is determined 1609 // ergonomically if page_size > 4K. 1610 static size_t _stack_red_zone_size; 1611 static size_t _stack_yellow_zone_size; 1612 static size_t _stack_reserved_zone_size; 1613 static size_t _stack_shadow_zone_size; 1614 public: 1615 inline size_t stack_available(address cur_sp); 1616 1617 static size_t stack_red_zone_size() { 1618 assert(_stack_red_zone_size > 0, "Don't call this before the field is initialized."); 1619 return _stack_red_zone_size; 1620 } 1621 static void set_stack_red_zone_size(size_t s) { 1622 assert(is_aligned(s, os::vm_page_size()), 1623 "We can not protect if the red zone size is not page aligned."); 1624 assert(_stack_red_zone_size == 0, "This should be called only once."); 1625 _stack_red_zone_size = s; 1626 } 1627 address stack_red_zone_base() { 1628 return (address)(stack_end() + stack_red_zone_size()); 1629 } 1630 bool in_stack_red_zone(address a) { 1631 return a <= stack_red_zone_base() && a >= stack_end(); 1632 } 1633 1634 static size_t stack_yellow_zone_size() { 1635 assert(_stack_yellow_zone_size > 0, "Don't call this before the field is initialized."); 1636 return _stack_yellow_zone_size; 1637 } 1638 static void set_stack_yellow_zone_size(size_t s) { 1639 assert(is_aligned(s, os::vm_page_size()), 1640 "We can not protect if the yellow zone size is not page aligned."); 1641 assert(_stack_yellow_zone_size == 0, "This should be called only once."); 1642 _stack_yellow_zone_size = s; 1643 } 1644 1645 static size_t stack_reserved_zone_size() { 1646 // _stack_reserved_zone_size may be 0. This indicates the feature is off. 1647 return _stack_reserved_zone_size; 1648 } 1649 static void set_stack_reserved_zone_size(size_t s) { 1650 assert(is_aligned(s, os::vm_page_size()), 1651 "We can not protect if the reserved zone size is not page aligned."); 1652 assert(_stack_reserved_zone_size == 0, "This should be called only once."); 1653 _stack_reserved_zone_size = s; 1654 } 1655 address stack_reserved_zone_base() { 1656 return (address)(stack_end() + 1657 (stack_red_zone_size() + stack_yellow_zone_size() + stack_reserved_zone_size())); 1658 } 1659 bool in_stack_reserved_zone(address a) { 1660 return (a <= stack_reserved_zone_base()) && 1661 (a >= (address)((intptr_t)stack_reserved_zone_base() - stack_reserved_zone_size())); 1662 } 1663 1664 static size_t stack_yellow_reserved_zone_size() { 1665 return _stack_yellow_zone_size + _stack_reserved_zone_size; 1666 } 1667 bool in_stack_yellow_reserved_zone(address a) { 1668 return (a <= stack_reserved_zone_base()) && (a >= stack_red_zone_base()); 1669 } 1670 1671 // Size of red + yellow + reserved zones. 1672 static size_t stack_guard_zone_size() { 1673 return stack_red_zone_size() + stack_yellow_reserved_zone_size(); 1674 } 1675 1676 static size_t stack_shadow_zone_size() { 1677 assert(_stack_shadow_zone_size > 0, "Don't call this before the field is initialized."); 1678 return _stack_shadow_zone_size; 1679 } 1680 static void set_stack_shadow_zone_size(size_t s) { 1681 // The shadow area is not allocated or protected, so 1682 // it needs not be page aligned. 1683 // But the stack bang currently assumes that it is a 1684 // multiple of page size. This guarantees that the bang 1685 // loop touches all pages in the shadow zone. 1686 // This can be guaranteed differently, as well. E.g., if 1687 // the page size is a multiple of 4K, banging in 4K steps 1688 // suffices to touch all pages. (Some pages are banged 1689 // several times, though.) 1690 assert(is_aligned(s, os::vm_page_size()), 1691 "Stack bang assumes multiple of page size."); 1692 assert(_stack_shadow_zone_size == 0, "This should be called only once."); 1693 _stack_shadow_zone_size = s; 1694 } 1695 1696 void create_stack_guard_pages(); 1697 void remove_stack_guard_pages(); 1698 1699 void enable_stack_reserved_zone(); 1700 void disable_stack_reserved_zone(); 1701 void enable_stack_yellow_reserved_zone(); 1702 void disable_stack_yellow_reserved_zone(); 1703 void enable_stack_red_zone(); 1704 void disable_stack_red_zone(); 1705 1706 inline bool stack_guard_zone_unused(); 1707 inline bool stack_yellow_reserved_zone_disabled(); 1708 inline bool stack_reserved_zone_disabled(); 1709 inline bool stack_guards_enabled(); 1710 1711 address reserved_stack_activation() const { return _reserved_stack_activation; } 1712 void set_reserved_stack_activation(address addr) { 1713 assert(_reserved_stack_activation == stack_base() 1714 || _reserved_stack_activation == NULL 1715 || addr == stack_base(), "Must not be set twice"); 1716 _reserved_stack_activation = addr; 1717 } 1718 1719 // Attempt to reguard the stack after a stack overflow may have occurred. 1720 // Returns true if (a) guard pages are not needed on this thread, (b) the 1721 // pages are already guarded, or (c) the pages were successfully reguarded. 1722 // Returns false if there is not enough stack space to reguard the pages, in 1723 // which case the caller should unwind a frame and try again. The argument 1724 // should be the caller's (approximate) sp. 1725 bool reguard_stack(address cur_sp); 1726 // Similar to above but see if current stackpoint is out of the guard area 1727 // and reguard if possible. 1728 bool reguard_stack(void); 1729 1730 address stack_overflow_limit() { return _stack_overflow_limit; } 1731 void set_stack_overflow_limit() { 1732 _stack_overflow_limit = 1733 stack_end() + MAX2(JavaThread::stack_guard_zone_size(), JavaThread::stack_shadow_zone_size()); 1734 } 1735 1736 // Misc. accessors/mutators 1737 void set_do_not_unlock(void) { _do_not_unlock_if_synchronized = true; } 1738 void clr_do_not_unlock(void) { _do_not_unlock_if_synchronized = false; } 1739 bool do_not_unlock(void) { return _do_not_unlock_if_synchronized; } 1740 1741 // For assembly stub generation 1742 static ByteSize threadObj_offset() { return byte_offset_of(JavaThread, _threadObj); } 1743 static ByteSize jni_environment_offset() { return byte_offset_of(JavaThread, _jni_environment); } 1744 static ByteSize pending_jni_exception_check_fn_offset() { 1745 return byte_offset_of(JavaThread, _pending_jni_exception_check_fn); 1746 } 1747 static ByteSize last_Java_sp_offset() { 1748 return byte_offset_of(JavaThread, _anchor) + JavaFrameAnchor::last_Java_sp_offset(); 1749 } 1750 static ByteSize last_Java_pc_offset() { 1751 return byte_offset_of(JavaThread, _anchor) + JavaFrameAnchor::last_Java_pc_offset(); 1752 } 1753 static ByteSize frame_anchor_offset() { 1754 return byte_offset_of(JavaThread, _anchor); 1755 } 1756 static ByteSize callee_target_offset() { return byte_offset_of(JavaThread, _callee_target); } 1757 static ByteSize vm_result_offset() { return byte_offset_of(JavaThread, _vm_result); } 1758 static ByteSize vm_result_2_offset() { return byte_offset_of(JavaThread, _vm_result_2); } 1759 static ByteSize thread_state_offset() { return byte_offset_of(JavaThread, _thread_state); } 1760 static ByteSize saved_exception_pc_offset() { return byte_offset_of(JavaThread, _saved_exception_pc); } 1761 static ByteSize osthread_offset() { return byte_offset_of(JavaThread, _osthread); } 1762 #if INCLUDE_JVMCI 1763 static ByteSize pending_deoptimization_offset() { return byte_offset_of(JavaThread, _pending_deoptimization); } 1764 static ByteSize pending_monitorenter_offset() { return byte_offset_of(JavaThread, _pending_monitorenter); } 1765 static ByteSize pending_failed_speculation_offset() { return byte_offset_of(JavaThread, _pending_failed_speculation); } 1766 static ByteSize jvmci_alternate_call_target_offset() { return byte_offset_of(JavaThread, _jvmci._alternate_call_target); } 1767 static ByteSize jvmci_implicit_exception_pc_offset() { return byte_offset_of(JavaThread, _jvmci._implicit_exception_pc); } 1768 static ByteSize jvmci_counters_offset() { return byte_offset_of(JavaThread, _jvmci_counters); } 1769 #endif // INCLUDE_JVMCI 1770 static ByteSize exception_oop_offset() { return byte_offset_of(JavaThread, _exception_oop); } 1771 static ByteSize exception_pc_offset() { return byte_offset_of(JavaThread, _exception_pc); } 1772 static ByteSize exception_handler_pc_offset() { return byte_offset_of(JavaThread, _exception_handler_pc); } 1773 static ByteSize stack_overflow_limit_offset() { return byte_offset_of(JavaThread, _stack_overflow_limit); } 1774 static ByteSize is_method_handle_return_offset() { return byte_offset_of(JavaThread, _is_method_handle_return); } 1775 static ByteSize stack_guard_state_offset() { return byte_offset_of(JavaThread, _stack_guard_state); } 1776 static ByteSize reserved_stack_activation_offset() { return byte_offset_of(JavaThread, _reserved_stack_activation); } 1777 static ByteSize suspend_flags_offset() { return byte_offset_of(JavaThread, _suspend_flags); } 1778 1779 static ByteSize do_not_unlock_if_synchronized_offset() { return byte_offset_of(JavaThread, _do_not_unlock_if_synchronized); } 1780 static ByteSize should_post_on_exceptions_flag_offset() { 1781 return byte_offset_of(JavaThread, _should_post_on_exceptions_flag); 1782 } 1783 static ByteSize doing_unsafe_access_offset() { return byte_offset_of(JavaThread, _doing_unsafe_access); } 1784 1785 // Returns the jni environment for this thread 1786 JNIEnv* jni_environment() { return &_jni_environment; } 1787 1788 static JavaThread* thread_from_jni_environment(JNIEnv* env) { 1789 JavaThread *thread_from_jni_env = (JavaThread*)((intptr_t)env - in_bytes(jni_environment_offset())); 1790 // Only return NULL if thread is off the thread list; starting to 1791 // exit should not return NULL. 1792 if (thread_from_jni_env->is_terminated()) { 1793 thread_from_jni_env->block_if_vm_exited(); 1794 return NULL; 1795 } else { 1796 return thread_from_jni_env; 1797 } 1798 } 1799 1800 // JNI critical regions. These can nest. 1801 bool in_critical() { return _jni_active_critical > 0; } 1802 bool in_last_critical() { return _jni_active_critical == 1; } 1803 inline void enter_critical(); 1804 void exit_critical() { 1805 assert(Thread::current() == this, "this must be current thread"); 1806 _jni_active_critical--; 1807 assert(_jni_active_critical >= 0, "JNI critical nesting problem?"); 1808 } 1809 1810 // Checked JNI: is the programmer required to check for exceptions, if so specify 1811 // which function name. Returning to a Java frame should implicitly clear the 1812 // pending check, this is done for Native->Java transitions (i.e. user JNI code). 1813 // VM->Java transistions are not cleared, it is expected that JNI code enclosed 1814 // within ThreadToNativeFromVM makes proper exception checks (i.e. VM internal). 1815 bool is_pending_jni_exception_check() const { return _pending_jni_exception_check_fn != NULL; } 1816 void clear_pending_jni_exception_check() { _pending_jni_exception_check_fn = NULL; } 1817 const char* get_pending_jni_exception_check() const { return _pending_jni_exception_check_fn; } 1818 void set_pending_jni_exception_check(const char* fn_name) { _pending_jni_exception_check_fn = (char*) fn_name; } 1819 1820 // For deadlock detection 1821 int depth_first_number() { return _depth_first_number; } 1822 void set_depth_first_number(int dfn) { _depth_first_number = dfn; } 1823 1824 private: 1825 void set_monitor_chunks(MonitorChunk* monitor_chunks) { _monitor_chunks = monitor_chunks; } 1826 1827 public: 1828 MonitorChunk* monitor_chunks() const { return _monitor_chunks; } 1829 void add_monitor_chunk(MonitorChunk* chunk); 1830 void remove_monitor_chunk(MonitorChunk* chunk); 1831 bool in_deopt_handler() const { return _in_deopt_handler > 0; } 1832 void inc_in_deopt_handler() { _in_deopt_handler++; } 1833 void dec_in_deopt_handler() { 1834 assert(_in_deopt_handler > 0, "mismatched deopt nesting"); 1835 if (_in_deopt_handler > 0) { // robustness 1836 _in_deopt_handler--; 1837 } 1838 } 1839 1840 private: 1841 void set_entry_point(ThreadFunction entry_point) { _entry_point = entry_point; } 1842 1843 public: 1844 1845 // Frame iteration; calls the function f for all frames on the stack 1846 void frames_do(void f(frame*, const RegisterMap*)); 1847 1848 // Memory operations 1849 void oops_do(OopClosure* f, CodeBlobClosure* cf); 1850 1851 // Sweeper operations 1852 virtual void nmethods_do(CodeBlobClosure* cf); 1853 1854 // RedefineClasses Support 1855 void metadata_do(MetadataClosure* f); 1856 1857 // Debug method asserting thread states are correct during a handshake operation. 1858 DEBUG_ONLY(void verify_states_for_handshake();) 1859 1860 // Misc. operations 1861 char* name() const { return (char*)get_thread_name(); } 1862 void print_on(outputStream* st, bool print_extended_info) const; 1863 void print_on(outputStream* st) const { print_on(st, false); } 1864 void print() const; 1865 void print_thread_state_on(outputStream*) const PRODUCT_RETURN; 1866 void print_on_error(outputStream* st, char* buf, int buflen) const; 1867 void print_name_on_error(outputStream* st, char* buf, int buflen) const; 1868 void verify(); 1869 const char* get_thread_name() const; 1870 protected: 1871 // factor out low-level mechanics for use in both normal and error cases 1872 virtual const char* get_thread_name_string(char* buf = NULL, int buflen = 0) const; 1873 public: 1874 // Accessing frames 1875 frame last_frame() { 1876 _anchor.make_walkable(this); 1877 return pd_last_frame(); 1878 } 1879 javaVFrame* last_java_vframe(RegisterMap* reg_map); 1880 1881 // Returns method at 'depth' java or native frames down the stack 1882 // Used for security checks 1883 Klass* security_get_caller_class(int depth); 1884 1885 // Print stack trace in external format 1886 void print_stack_on(outputStream* st); 1887 void print_stack() { print_stack_on(tty); } 1888 1889 // Print stack traces in various internal formats 1890 void trace_stack() PRODUCT_RETURN; 1891 void trace_stack_from(vframe* start_vf) PRODUCT_RETURN; 1892 void trace_frames() PRODUCT_RETURN; 1893 1894 // Print an annotated view of the stack frames 1895 void print_frame_layout(int depth = 0, bool validate_only = false) NOT_DEBUG_RETURN; 1896 void validate_frame_layout() { 1897 print_frame_layout(0, true); 1898 } 1899 1900 // Function for testing deoptimization 1901 void deoptimize(); 1902 void make_zombies(); 1903 1904 void deoptimize_marked_methods(); 1905 1906 public: 1907 // Returns the running thread as a JavaThread 1908 static inline JavaThread* current(); 1909 1910 // Returns the active Java thread. Do not use this if you know you are calling 1911 // from a JavaThread, as it's slower than JavaThread::current. If called from 1912 // the VMThread, it also returns the JavaThread that instigated the VMThread's 1913 // operation. You may not want that either. 1914 static JavaThread* active(); 1915 1916 inline CompilerThread* as_CompilerThread(); 1917 1918 protected: 1919 virtual void pre_run(); 1920 virtual void run(); 1921 void thread_main_inner(); 1922 virtual void post_run(); 1923 1924 1925 private: 1926 GrowableArray<oop>* _array_for_gc; 1927 public: 1928 1929 void register_array_for_gc(GrowableArray<oop>* array) { _array_for_gc = array; } 1930 1931 public: 1932 // Thread local information maintained by JVMTI. 1933 void set_jvmti_thread_state(JvmtiThreadState *value) { _jvmti_thread_state = value; } 1934 // A JvmtiThreadState is lazily allocated. This jvmti_thread_state() 1935 // getter is used to get this JavaThread's JvmtiThreadState if it has 1936 // one which means NULL can be returned. JvmtiThreadState::state_for() 1937 // is used to get the specified JavaThread's JvmtiThreadState if it has 1938 // one or it allocates a new JvmtiThreadState for the JavaThread and 1939 // returns it. JvmtiThreadState::state_for() will return NULL only if 1940 // the specified JavaThread is exiting. 1941 JvmtiThreadState *jvmti_thread_state() const { return _jvmti_thread_state; } 1942 static ByteSize jvmti_thread_state_offset() { return byte_offset_of(JavaThread, _jvmti_thread_state); } 1943 1944 // JVMTI PopFrame support 1945 // Setting and clearing popframe_condition 1946 // All of these enumerated values are bits. popframe_pending 1947 // indicates that a PopFrame() has been requested and not yet been 1948 // completed. popframe_processing indicates that that PopFrame() is in 1949 // the process of being completed. popframe_force_deopt_reexecution_bit 1950 // indicates that special handling is required when returning to a 1951 // deoptimized caller. 1952 enum PopCondition { 1953 popframe_inactive = 0x00, 1954 popframe_pending_bit = 0x01, 1955 popframe_processing_bit = 0x02, 1956 popframe_force_deopt_reexecution_bit = 0x04 1957 }; 1958 PopCondition popframe_condition() { return (PopCondition) _popframe_condition; } 1959 void set_popframe_condition(PopCondition c) { _popframe_condition = c; } 1960 void set_popframe_condition_bit(PopCondition c) { _popframe_condition |= c; } 1961 void clear_popframe_condition() { _popframe_condition = popframe_inactive; } 1962 static ByteSize popframe_condition_offset() { return byte_offset_of(JavaThread, _popframe_condition); } 1963 bool has_pending_popframe() { return (popframe_condition() & popframe_pending_bit) != 0; } 1964 bool popframe_forcing_deopt_reexecution() { return (popframe_condition() & popframe_force_deopt_reexecution_bit) != 0; } 1965 void clear_popframe_forcing_deopt_reexecution() { _popframe_condition &= ~popframe_force_deopt_reexecution_bit; } 1966 #ifdef CC_INTERP 1967 bool pop_frame_pending(void) { return ((_popframe_condition & popframe_pending_bit) != 0); } 1968 void clr_pop_frame_pending(void) { _popframe_condition = popframe_inactive; } 1969 bool pop_frame_in_process(void) { return ((_popframe_condition & popframe_processing_bit) != 0); } 1970 void set_pop_frame_in_process(void) { _popframe_condition |= popframe_processing_bit; } 1971 void clr_pop_frame_in_process(void) { _popframe_condition &= ~popframe_processing_bit; } 1972 #endif 1973 1974 int frames_to_pop_failed_realloc() const { return _frames_to_pop_failed_realloc; } 1975 void set_frames_to_pop_failed_realloc(int nb) { _frames_to_pop_failed_realloc = nb; } 1976 void dec_frames_to_pop_failed_realloc() { _frames_to_pop_failed_realloc--; } 1977 1978 private: 1979 // Saved incoming arguments to popped frame. 1980 // Used only when popped interpreted frame returns to deoptimized frame. 1981 void* _popframe_preserved_args; 1982 int _popframe_preserved_args_size; 1983 1984 public: 1985 void popframe_preserve_args(ByteSize size_in_bytes, void* start); 1986 void* popframe_preserved_args(); 1987 ByteSize popframe_preserved_args_size(); 1988 WordSize popframe_preserved_args_size_in_words(); 1989 void popframe_free_preserved_args(); 1990 1991 1992 private: 1993 JvmtiThreadState *_jvmti_thread_state; 1994 1995 // Used by the interpreter in fullspeed mode for frame pop, method 1996 // entry, method exit and single stepping support. This field is 1997 // only set to non-zero by the VM_EnterInterpOnlyMode VM operation. 1998 // It can be set to zero asynchronously (i.e., without a VM operation 1999 // or a lock) so we have to be very careful. 2000 int _interp_only_mode; 2001 2002 public: 2003 // used by the interpreter for fullspeed debugging support (see above) 2004 static ByteSize interp_only_mode_offset() { return byte_offset_of(JavaThread, _interp_only_mode); } 2005 bool is_interp_only_mode() { return (_interp_only_mode != 0); } 2006 int get_interp_only_mode() { return _interp_only_mode; } 2007 void increment_interp_only_mode() { ++_interp_only_mode; } 2008 void decrement_interp_only_mode() { --_interp_only_mode; } 2009 2010 // support for cached flag that indicates whether exceptions need to be posted for this thread 2011 // if this is false, we can avoid deoptimizing when events are thrown 2012 // this gets set to reflect whether jvmtiExport::post_exception_throw would actually do anything 2013 private: 2014 int _should_post_on_exceptions_flag; 2015 2016 public: 2017 int should_post_on_exceptions_flag() { return _should_post_on_exceptions_flag; } 2018 void set_should_post_on_exceptions_flag(int val) { _should_post_on_exceptions_flag = val; } 2019 2020 private: 2021 ThreadStatistics *_thread_stat; 2022 2023 public: 2024 ThreadStatistics* get_thread_stat() const { return _thread_stat; } 2025 2026 // Return a blocker object for which this thread is blocked parking. 2027 oop current_park_blocker(); 2028 2029 private: 2030 static size_t _stack_size_at_create; 2031 2032 public: 2033 static inline size_t stack_size_at_create(void) { 2034 return _stack_size_at_create; 2035 } 2036 static inline void set_stack_size_at_create(size_t value) { 2037 _stack_size_at_create = value; 2038 } 2039 2040 // Machine dependent stuff 2041 #include OS_CPU_HEADER(thread) 2042 2043 // JSR166 per-thread parker 2044 private: 2045 Parker* _parker; 2046 public: 2047 Parker* parker() { return _parker; } 2048 2049 // Biased locking support 2050 private: 2051 GrowableArray<MonitorInfo*>* _cached_monitor_info; 2052 public: 2053 GrowableArray<MonitorInfo*>* cached_monitor_info() { return _cached_monitor_info; } 2054 void set_cached_monitor_info(GrowableArray<MonitorInfo*>* info) { _cached_monitor_info = info; } 2055 2056 // clearing/querying jni attach status 2057 bool is_attaching_via_jni() const { return _jni_attach_state == _attaching_via_jni; } 2058 bool has_attached_via_jni() const { return is_attaching_via_jni() || _jni_attach_state == _attached_via_jni; } 2059 inline void set_done_attaching_via_jni(); 2060 2061 // Stack dump assistance: 2062 // Track the class we want to initialize but for which we have to wait 2063 // on its init_lock() because it is already being initialized. 2064 void set_class_to_be_initialized(InstanceKlass* k); 2065 InstanceKlass* class_to_be_initialized() const; 2066 2067 private: 2068 InstanceKlass* _class_to_be_initialized; 2069 2070 // java.lang.Thread.sleep support 2071 ParkEvent * _SleepEvent; 2072 public: 2073 bool sleep(jlong millis); 2074 2075 // java.lang.Thread interruption support 2076 void interrupt(); 2077 bool is_interrupted(bool clear_interrupted); 2078 2079 }; 2080 2081 // Inline implementation of JavaThread::current 2082 inline JavaThread* JavaThread::current() { 2083 Thread* thread = Thread::current(); 2084 assert(thread->is_Java_thread(), "just checking"); 2085 return (JavaThread*)thread; 2086 } 2087 2088 inline CompilerThread* JavaThread::as_CompilerThread() { 2089 assert(is_Compiler_thread(), "just checking"); 2090 return (CompilerThread*)this; 2091 } 2092 2093 // Dedicated thread to sweep the code cache 2094 class CodeCacheSweeperThread : public JavaThread { 2095 CompiledMethod* _scanned_compiled_method; // nmethod being scanned by the sweeper 2096 public: 2097 CodeCacheSweeperThread(); 2098 // Track the nmethod currently being scanned by the sweeper 2099 void set_scanned_compiled_method(CompiledMethod* cm) { 2100 assert(_scanned_compiled_method == NULL || cm == NULL, "should reset to NULL before writing a new value"); 2101 _scanned_compiled_method = cm; 2102 } 2103 2104 // Hide sweeper thread from external view. 2105 bool is_hidden_from_external_view() const { return true; } 2106 2107 bool is_Code_cache_sweeper_thread() const { return true; } 2108 2109 // Prevent GC from unloading _scanned_compiled_method 2110 void oops_do(OopClosure* f, CodeBlobClosure* cf); 2111 void nmethods_do(CodeBlobClosure* cf); 2112 }; 2113 2114 // A thread used for Compilation. 2115 class CompilerThread : public JavaThread { 2116 friend class VMStructs; 2117 private: 2118 CompilerCounters* _counters; 2119 2120 ciEnv* _env; 2121 CompileLog* _log; 2122 CompileTask* volatile _task; // print_threads_compiling can read this concurrently. 2123 CompileQueue* _queue; 2124 BufferBlob* _buffer_blob; 2125 2126 AbstractCompiler* _compiler; 2127 TimeStamp _idle_time; 2128 2129 public: 2130 2131 static CompilerThread* current(); 2132 2133 CompilerThread(CompileQueue* queue, CompilerCounters* counters); 2134 ~CompilerThread(); 2135 2136 bool is_Compiler_thread() const { return true; } 2137 2138 virtual bool can_call_java() const; 2139 2140 // Hide native compiler threads from external view. 2141 bool is_hidden_from_external_view() const { return !can_call_java(); } 2142 2143 void set_compiler(AbstractCompiler* c) { _compiler = c; } 2144 AbstractCompiler* compiler() const { return _compiler; } 2145 2146 CompileQueue* queue() const { return _queue; } 2147 CompilerCounters* counters() const { return _counters; } 2148 2149 // Get/set the thread's compilation environment. 2150 ciEnv* env() { return _env; } 2151 void set_env(ciEnv* env) { _env = env; } 2152 2153 BufferBlob* get_buffer_blob() const { return _buffer_blob; } 2154 void set_buffer_blob(BufferBlob* b) { _buffer_blob = b; } 2155 2156 // Get/set the thread's logging information 2157 CompileLog* log() { return _log; } 2158 void init_log(CompileLog* log) { 2159 // Set once, for good. 2160 assert(_log == NULL, "set only once"); 2161 _log = log; 2162 } 2163 2164 void start_idle_timer() { _idle_time.update(); } 2165 jlong idle_time_millis() { 2166 return TimeHelper::counter_to_millis(_idle_time.ticks_since_update()); 2167 } 2168 2169 #ifndef PRODUCT 2170 private: 2171 IdealGraphPrinter *_ideal_graph_printer; 2172 public: 2173 IdealGraphPrinter *ideal_graph_printer() { return _ideal_graph_printer; } 2174 void set_ideal_graph_printer(IdealGraphPrinter *n) { _ideal_graph_printer = n; } 2175 #endif 2176 2177 // Get/set the thread's current task 2178 CompileTask* task() { return _task; } 2179 void set_task(CompileTask* task) { _task = task; } 2180 }; 2181 2182 inline CompilerThread* CompilerThread::current() { 2183 return JavaThread::current()->as_CompilerThread(); 2184 } 2185 2186 // The active thread queue. It also keeps track of the current used 2187 // thread priorities. 2188 class Threads: AllStatic { 2189 friend class VMStructs; 2190 private: 2191 static int _number_of_threads; 2192 static int _number_of_non_daemon_threads; 2193 static int _return_code; 2194 static uintx _thread_claim_token; 2195 #ifdef ASSERT 2196 static bool _vm_complete; 2197 #endif 2198 2199 static void initialize_java_lang_classes(JavaThread* main_thread, TRAPS); 2200 static void initialize_jsr292_core_classes(TRAPS); 2201 2202 public: 2203 // Thread management 2204 // force_daemon is a concession to JNI, where we may need to add a 2205 // thread to the thread list before allocating its thread object 2206 static void add(JavaThread* p, bool force_daemon = false); 2207 static void remove(JavaThread* p, bool is_daemon); 2208 static void non_java_threads_do(ThreadClosure* tc); 2209 static void java_threads_do(ThreadClosure* tc); 2210 static void java_threads_and_vm_thread_do(ThreadClosure* tc); 2211 static void threads_do(ThreadClosure* tc); 2212 static void possibly_parallel_threads_do(bool is_par, ThreadClosure* tc); 2213 2214 // Initializes the vm and creates the vm thread 2215 static jint create_vm(JavaVMInitArgs* args, bool* canTryAgain); 2216 static void convert_vm_init_libraries_to_agents(); 2217 static void create_vm_init_libraries(); 2218 static void create_vm_init_agents(); 2219 static void shutdown_vm_agents(); 2220 static bool destroy_vm(); 2221 // Supported VM versions via JNI 2222 // Includes JNI_VERSION_1_1 2223 static jboolean is_supported_jni_version_including_1_1(jint version); 2224 // Does not include JNI_VERSION_1_1 2225 static jboolean is_supported_jni_version(jint version); 2226 2227 // The "thread claim token" provides a way for threads to be claimed 2228 // by parallel worker tasks. 2229 // 2230 // Each thread contains a "token" field. A task will claim the 2231 // thread only if its token is different from the global token, 2232 // which is updated by calling change_thread_claim_token(). When 2233 // a thread is claimed, it's token is set to the global token value 2234 // so other threads in the same iteration pass won't claim it. 2235 // 2236 // For this to work change_thread_claim_token() needs to be called 2237 // exactly once in sequential code before starting parallel tasks 2238 // that should claim threads. 2239 // 2240 // New threads get their token set to 0 and change_thread_claim_token() 2241 // never sets the global token to 0. 2242 static uintx thread_claim_token() { return _thread_claim_token; } 2243 static void change_thread_claim_token(); 2244 static void assert_all_threads_claimed() NOT_DEBUG_RETURN; 2245 2246 // Apply "f->do_oop" to all root oops in all threads. 2247 // This version may only be called by sequential code. 2248 static void oops_do(OopClosure* f, CodeBlobClosure* cf); 2249 // This version may be called by sequential or parallel code. 2250 static void possibly_parallel_oops_do(bool is_par, OopClosure* f, CodeBlobClosure* cf); 2251 2252 // Sweeper 2253 static void nmethods_do(CodeBlobClosure* cf); 2254 2255 // RedefineClasses support 2256 static void metadata_do(MetadataClosure* f); 2257 static void metadata_handles_do(void f(Metadata*)); 2258 2259 #ifdef ASSERT 2260 static bool is_vm_complete() { return _vm_complete; } 2261 #endif // ASSERT 2262 2263 // Verification 2264 static void verify(); 2265 static void print_on(outputStream* st, bool print_stacks, bool internal_format, bool print_concurrent_locks, bool print_extended_info); 2266 static void print(bool print_stacks, bool internal_format) { 2267 // this function is only used by debug.cpp 2268 print_on(tty, print_stacks, internal_format, false /* no concurrent lock printed */, false /* simple format */); 2269 } 2270 static void print_on_error(outputStream* st, Thread* current, char* buf, int buflen); 2271 static void print_on_error(Thread* this_thread, outputStream* st, Thread* current, char* buf, 2272 int buflen, bool* found_current); 2273 static void print_threads_compiling(outputStream* st, char* buf, int buflen, bool short_form = false); 2274 2275 // Get Java threads that are waiting to enter a monitor. 2276 static GrowableArray<JavaThread*>* get_pending_threads(ThreadsList * t_list, 2277 int count, address monitor); 2278 2279 // Get owning Java thread from the monitor's owner field. 2280 static JavaThread *owning_thread_from_monitor_owner(ThreadsList * t_list, 2281 address owner); 2282 2283 // Number of threads on the active threads list 2284 static int number_of_threads() { return _number_of_threads; } 2285 // Number of non-daemon threads on the active threads list 2286 static int number_of_non_daemon_threads() { return _number_of_non_daemon_threads; } 2287 2288 // Deoptimizes all frames tied to marked nmethods 2289 static void deoptimized_wrt_marked_nmethods(); 2290 2291 struct Test; // For private gtest access. 2292 }; 2293 2294 class SignalHandlerMark: public StackObj { 2295 private: 2296 Thread* _thread; 2297 public: 2298 SignalHandlerMark(Thread* t) { 2299 _thread = t; 2300 if (_thread) _thread->enter_signal_handler(); 2301 } 2302 ~SignalHandlerMark() { 2303 if (_thread) _thread->leave_signal_handler(); 2304 _thread = NULL; 2305 } 2306 }; 2307 2308 2309 #endif // SHARE_RUNTIME_THREAD_HPP