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