1 /* 2 * Copyright (c) 1997, 2018, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. 8 * 9 * This code is distributed in the hope that it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 12 * version 2 for more details (a copy is included in the LICENSE file that 13 * accompanied this code). 14 * 15 * You should have received a copy of the GNU General Public License version 16 * 2 along with this work; if not, write to the Free Software Foundation, 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 18 * 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 20 * or visit www.oracle.com if you need additional information or have any 21 * questions. 22 * 23 */ 24 25 #ifndef SHARE_VM_RUNTIME_THREAD_HPP 26 #define SHARE_VM_RUNTIME_THREAD_HPP 27 28 #include "jni.h" 29 #include "gc/shared/gcThreadLocalData.hpp" 30 #include "gc/shared/threadLocalAllocBuffer.hpp" 31 #include "memory/allocation.hpp" 32 #include "oops/oop.hpp" 33 #include "prims/jvmtiExport.hpp" 34 #include "runtime/frame.hpp" 35 #include "runtime/globals.hpp" 36 #include "runtime/handshake.hpp" 37 #include "runtime/javaFrameAnchor.hpp" 38 #include "runtime/jniHandles.hpp" 39 #include "runtime/mutexLocker.hpp" 40 #include "runtime/os.hpp" 41 #include "runtime/osThread.hpp" 42 #include "runtime/park.hpp" 43 #include "runtime/safepoint.hpp" 44 #include "runtime/stubRoutines.hpp" 45 #include "runtime/threadHeapSampler.hpp" 46 #include "runtime/threadLocalStorage.hpp" 47 #include "runtime/threadStatisticalInfo.hpp" 48 #include "runtime/unhandledOops.hpp" 49 #include "utilities/align.hpp" 50 #include "utilities/exceptions.hpp" 51 #include "utilities/macros.hpp" 52 #ifdef ZERO 53 # include "stack_zero.hpp" 54 #endif 55 #if INCLUDE_JFR 56 #include "jfr/support/jfrThreadExtension.hpp" 57 #endif 58 59 60 class SafeThreadsListPtr; 61 class ThreadSafepointState; 62 class ThreadsList; 63 class ThreadsSMRSupport; 64 65 class JvmtiThreadState; 66 class ThreadStatistics; 67 class ConcurrentLocksDump; 68 class ParkEvent; 69 class Parker; 70 71 class ciEnv; 72 class CompileThread; 73 class CompileLog; 74 class CompileTask; 75 class CompileQueue; 76 class CompilerCounters; 77 class vframeArray; 78 79 class DeoptResourceMark; 80 class jvmtiDeferredLocalVariableSet; 81 82 class GCTaskQueue; 83 class ThreadClosure; 84 class IdealGraphPrinter; 85 86 class Metadata; 87 template <class T, MEMFLAGS F> class ChunkedList; 88 typedef ChunkedList<Metadata*, mtInternal> MetadataOnStackBuffer; 89 90 DEBUG_ONLY(class ResourceMark;) 91 92 class WorkerThread; 93 94 // Class hierarchy 95 // - Thread 96 // - JavaThread 97 // - various subclasses eg CompilerThread, ServiceThread 98 // - NonJavaThread 99 // - NamedThread 100 // - VMThread 101 // - ConcurrentGCThread 102 // - WorkerThread 103 // - GangWorker 104 // - GCTaskThread 105 // - WatcherThread 106 // - JfrThreadSampler 107 // 108 // All Thread subclasses must be either JavaThread or NonJavaThread. 109 // This means !t->is_Java_thread() iff t is a NonJavaThread, or t is 110 // a partially constructed/destroyed Thread. 111 112 class Thread: public ThreadShadow { 113 friend class VMStructs; 114 friend class JVMCIVMStructs; 115 private: 116 117 #ifndef USE_LIBRARY_BASED_TLS_ONLY 118 // Current thread is maintained as a thread-local variable 119 static THREAD_LOCAL_DECL Thread* _thr_current; 120 #endif 121 122 private: 123 // Thread local data area available to the GC. The internal 124 // structure and contents of this data area is GC-specific. 125 // Only GC and GC barrier code should access this data area. 126 GCThreadLocalData _gc_data; 127 128 public: 129 static ByteSize gc_data_offset() { 130 return byte_offset_of(Thread, _gc_data); 131 } 132 133 template <typename T> T* gc_data() { 134 STATIC_ASSERT(sizeof(T) <= sizeof(_gc_data)); 135 return reinterpret_cast<T*>(&_gc_data); 136 } 137 138 // Exception handling 139 // (Note: _pending_exception and friends are in ThreadShadow) 140 //oop _pending_exception; // pending exception for current thread 141 // const char* _exception_file; // file information for exception (debugging only) 142 // int _exception_line; // line information for exception (debugging only) 143 protected: 144 // Support for forcing alignment of thread objects for biased locking 145 void* _real_malloc_address; 146 147 // JavaThread lifecycle support: 148 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 149 friend class ScanHazardPtrGatherProtectedThreadsClosure; // for cmpxchg_threads_hazard_ptr(), get_threads_hazard_ptr(), is_hazard_ptr_tagged() access 150 friend class ScanHazardPtrGatherThreadsListClosure; // for get_threads_hazard_ptr(), untag_hazard_ptr() access 151 friend class ScanHazardPtrPrintMatchingThreadsClosure; // for get_threads_hazard_ptr(), is_hazard_ptr_tagged() access 152 friend class ThreadsSMRSupport; // for _nested_threads_hazard_ptr_cnt, _threads_hazard_ptr, _threads_list_ptr access 153 154 ThreadsList* volatile _threads_hazard_ptr; 155 SafeThreadsListPtr* _threads_list_ptr; 156 ThreadsList* cmpxchg_threads_hazard_ptr(ThreadsList* exchange_value, ThreadsList* compare_value); 157 ThreadsList* get_threads_hazard_ptr(); 158 void set_threads_hazard_ptr(ThreadsList* new_list); 159 static bool is_hazard_ptr_tagged(ThreadsList* list) { 160 return (intptr_t(list) & intptr_t(1)) == intptr_t(1); 161 } 162 static ThreadsList* tag_hazard_ptr(ThreadsList* list) { 163 return (ThreadsList*)(intptr_t(list) | intptr_t(1)); 164 } 165 static ThreadsList* untag_hazard_ptr(ThreadsList* list) { 166 return (ThreadsList*)(intptr_t(list) & ~intptr_t(1)); 167 } 168 // This field is enabled via -XX:+EnableThreadSMRStatistics: 169 uint _nested_threads_hazard_ptr_cnt; 170 void dec_nested_threads_hazard_ptr_cnt() { 171 assert(_nested_threads_hazard_ptr_cnt != 0, "mismatched {dec,inc}_nested_threads_hazard_ptr_cnt()"); 172 _nested_threads_hazard_ptr_cnt--; 173 } 174 void inc_nested_threads_hazard_ptr_cnt() { 175 _nested_threads_hazard_ptr_cnt++; 176 } 177 uint nested_threads_hazard_ptr_cnt() { 178 return _nested_threads_hazard_ptr_cnt; 179 } 180 181 public: 182 void* operator new(size_t size) throw() { return allocate(size, true); } 183 void* operator new(size_t size, const std::nothrow_t& nothrow_constant) throw() { 184 return allocate(size, false); } 185 void operator delete(void* p); 186 187 protected: 188 static void* allocate(size_t size, bool throw_excpt, MEMFLAGS flags = mtThread); 189 private: 190 191 // *************************************************************** 192 // Suspend and resume support 193 // *************************************************************** 194 // 195 // VM suspend/resume no longer exists - it was once used for various 196 // things including safepoints but was deprecated and finally removed 197 // in Java 7. Because VM suspension was considered "internal" Java-level 198 // suspension was considered "external", and this legacy naming scheme 199 // remains. 200 // 201 // External suspend/resume requests come from JVM_SuspendThread, 202 // JVM_ResumeThread, JVMTI SuspendThread, and finally JVMTI 203 // ResumeThread. External 204 // suspend requests cause _external_suspend to be set and external 205 // resume requests cause _external_suspend to be cleared. 206 // External suspend requests do not nest on top of other external 207 // suspend requests. The higher level APIs reject suspend requests 208 // for already suspended threads. 209 // 210 // The external_suspend 211 // flag is checked by has_special_runtime_exit_condition() and java thread 212 // will self-suspend when handle_special_runtime_exit_condition() is 213 // called. Most uses of the _thread_blocked state in JavaThreads are 214 // considered the same as being externally suspended; if the blocking 215 // condition lifts, the JavaThread will self-suspend. Other places 216 // where VM checks for external_suspend include: 217 // + mutex granting (do not enter monitors when thread is suspended) 218 // + state transitions from _thread_in_native 219 // 220 // In general, java_suspend() does not wait for an external suspend 221 // request to complete. When it returns, the only guarantee is that 222 // the _external_suspend field is true. 223 // 224 // wait_for_ext_suspend_completion() is used to wait for an external 225 // suspend request to complete. External suspend requests are usually 226 // followed by some other interface call that requires the thread to 227 // be quiescent, e.g., GetCallTrace(). By moving the "wait time" into 228 // the interface that requires quiescence, we give the JavaThread a 229 // chance to self-suspend before we need it to be quiescent. This 230 // improves overall suspend/query performance. 231 // 232 // _suspend_flags controls the behavior of java_ suspend/resume. 233 // It must be set under the protection of SR_lock. Read from the flag is 234 // OK without SR_lock as long as the value is only used as a hint. 235 // (e.g., check _external_suspend first without lock and then recheck 236 // inside SR_lock and finish the suspension) 237 // 238 // _suspend_flags is also overloaded for other "special conditions" so 239 // that a single check indicates whether any special action is needed 240 // eg. for async exceptions. 241 // ------------------------------------------------------------------- 242 // Notes: 243 // 1. The suspend/resume logic no longer uses ThreadState in OSThread 244 // but we still update its value to keep other part of the system (mainly 245 // JVMTI) happy. ThreadState is legacy code (see notes in 246 // osThread.hpp). 247 // 248 // 2. It would be more natural if set_external_suspend() is private and 249 // part of java_suspend(), but that probably would affect the suspend/query 250 // performance. Need more investigation on this. 251 252 // suspend/resume lock: used for self-suspend 253 Monitor* _SR_lock; 254 255 protected: 256 enum SuspendFlags { 257 // NOTE: avoid using the sign-bit as cc generates different test code 258 // when the sign-bit is used, and sometimes incorrectly - see CR 6398077 259 260 _external_suspend = 0x20000000U, // thread is asked to self suspend 261 _ext_suspended = 0x40000000U, // thread has self-suspended 262 _deopt_suspend = 0x10000000U, // thread needs to self suspend for deopt 263 264 _has_async_exception = 0x00000001U, // there is a pending async exception 265 _critical_native_unlock = 0x00000002U, // Must call back to unlock JNI critical lock 266 267 _trace_flag = 0x00000004U // call tracing backend 268 }; 269 270 // various suspension related flags - atomically updated 271 // overloaded for async exception checking in check_special_condition_for_native_trans. 272 volatile uint32_t _suspend_flags; 273 274 private: 275 int _num_nested_signal; 276 277 DEBUG_ONLY(bool _suspendible_thread;) 278 279 public: 280 void enter_signal_handler() { _num_nested_signal++; } 281 void leave_signal_handler() { _num_nested_signal--; } 282 bool is_inside_signal_handler() const { return _num_nested_signal > 0; } 283 284 #ifdef ASSERT 285 void set_suspendible_thread() { 286 _suspendible_thread = true; 287 } 288 289 void clear_suspendible_thread() { 290 _suspendible_thread = false; 291 } 292 293 bool is_suspendible_thread() { return _suspendible_thread; } 294 #endif 295 296 private: 297 // Active_handles points to a block of handles 298 JNIHandleBlock* _active_handles; 299 300 // One-element thread local free list 301 JNIHandleBlock* _free_handle_block; 302 303 // Point to the last handle mark 304 HandleMark* _last_handle_mark; 305 306 // The parity of the last strong_roots iteration in which this thread was 307 // claimed as a task. 308 int _oops_do_parity; 309 310 // Support for GlobalCounter 311 private: 312 volatile uintx _rcu_counter; 313 public: 314 volatile uintx* get_rcu_counter() { 315 return &_rcu_counter; 316 } 317 318 public: 319 void set_last_handle_mark(HandleMark* mark) { _last_handle_mark = mark; } 320 HandleMark* last_handle_mark() const { return _last_handle_mark; } 321 private: 322 323 // debug support for checking if code does allow safepoints or not 324 // GC points in the VM can happen because of allocation, invoking a VM operation, or blocking on 325 // mutex, or blocking on an object synchronizer (Java locking). 326 // If !allow_safepoint(), then an assertion failure will happen in any of the above cases 327 // If !allow_allocation(), then an assertion failure will happen during allocation 328 // (Hence, !allow_safepoint() => !allow_allocation()). 329 // 330 // The two classes NoSafepointVerifier and No_Allocation_Verifier are used to set these counters. 331 // 332 NOT_PRODUCT(int _allow_safepoint_count;) // If 0, thread allow a safepoint to happen 333 debug_only(int _allow_allocation_count;) // If 0, the thread is allowed to allocate oops. 334 335 // Used by SkipGCALot class. 336 NOT_PRODUCT(bool _skip_gcalot;) // Should we elide gc-a-lot? 337 338 friend class NoAllocVerifier; 339 friend class NoSafepointVerifier; 340 friend class PauseNoSafepointVerifier; 341 friend class GCLocker; 342 343 volatile void* _polling_page; // Thread local polling page 344 345 ThreadLocalAllocBuffer _tlab; // Thread-local eden 346 jlong _allocated_bytes; // Cumulative number of bytes allocated on 347 // the Java heap 348 ThreadHeapSampler _heap_sampler; // For use when sampling the memory. 349 350 ThreadStatisticalInfo _statistical_info; // Statistics about the thread 351 352 JFR_ONLY(DEFINE_THREAD_LOCAL_FIELD_JFR;) // Thread-local data for jfr 353 354 int _vm_operation_started_count; // VM_Operation support 355 int _vm_operation_completed_count; // VM_Operation support 356 357 ObjectMonitor* _current_pending_monitor; // ObjectMonitor this thread 358 // is waiting to lock 359 bool _current_pending_monitor_is_from_java; // locking is from Java code 360 361 // ObjectMonitor on which this thread called Object.wait() 362 ObjectMonitor* _current_waiting_monitor; 363 364 // Private thread-local objectmonitor list - a simple cache organized as a SLL. 365 public: 366 ObjectMonitor* omFreeList; 367 int omFreeCount; // length of omFreeList 368 int omFreeProvision; // reload chunk size 369 ObjectMonitor* omInUseList; // SLL to track monitors in circulation 370 int omInUseCount; // length of omInUseList 371 372 #ifdef ASSERT 373 private: 374 bool _visited_for_critical_count; 375 376 public: 377 void set_visited_for_critical_count(bool z) { _visited_for_critical_count = z; } 378 bool was_visited_for_critical_count() const { return _visited_for_critical_count; } 379 #endif 380 381 public: 382 enum { 383 is_definitely_current_thread = true 384 }; 385 386 // Constructor 387 Thread(); 388 virtual ~Thread() = 0; // Thread is abstract. 389 390 // Manage Thread::current() 391 void initialize_thread_current(); 392 void clear_thread_current(); // TLS cleanup needed before threads terminate 393 394 public: 395 // thread entry point 396 virtual void run(); 397 398 // Testers 399 virtual bool is_VM_thread() const { return false; } 400 virtual bool is_Java_thread() const { return false; } 401 virtual bool is_Compiler_thread() const { return false; } 402 virtual bool is_Code_cache_sweeper_thread() const { return false; } 403 virtual bool is_hidden_from_external_view() const { return false; } 404 virtual bool is_jvmti_agent_thread() const { return false; } 405 // True iff the thread can perform GC operations at a safepoint. 406 // Generally will be true only of VM thread and parallel GC WorkGang 407 // threads. 408 virtual bool is_GC_task_thread() const { return false; } 409 virtual bool is_Watcher_thread() const { return false; } 410 virtual bool is_ConcurrentGC_thread() const { return false; } 411 virtual bool is_Named_thread() const { return false; } 412 virtual bool is_Worker_thread() const { return false; } 413 414 // Can this thread make Java upcalls 415 virtual bool can_call_java() const { return false; } 416 417 // Casts 418 virtual WorkerThread* as_Worker_thread() const { return NULL; } 419 420 virtual char* name() const { return (char*)"Unknown thread"; } 421 422 // Returns the current thread (ASSERTS if NULL) 423 static inline Thread* current(); 424 // Returns the current thread, or NULL if not attached 425 static inline Thread* current_or_null(); 426 // Returns the current thread, or NULL if not attached, and is 427 // safe for use from signal-handlers 428 static inline Thread* current_or_null_safe(); 429 430 // Common thread operations 431 #ifdef ASSERT 432 static void check_for_dangling_thread_pointer(Thread *thread); 433 #endif 434 static void set_priority(Thread* thread, ThreadPriority priority); 435 static ThreadPriority get_priority(const Thread* const thread); 436 static void start(Thread* thread); 437 static void interrupt(Thread* thr); 438 static bool is_interrupted(Thread* thr, bool clear_interrupted); 439 440 void set_native_thread_name(const char *name) { 441 assert(Thread::current() == this, "set_native_thread_name can only be called on the current thread"); 442 os::set_native_thread_name(name); 443 } 444 445 ObjectMonitor** omInUseList_addr() { return (ObjectMonitor **)&omInUseList; } 446 Monitor* SR_lock() const { return _SR_lock; } 447 448 bool has_async_exception() const { return (_suspend_flags & _has_async_exception) != 0; } 449 450 inline void set_suspend_flag(SuspendFlags f); 451 inline void clear_suspend_flag(SuspendFlags f); 452 453 inline void set_has_async_exception(); 454 inline void clear_has_async_exception(); 455 456 bool do_critical_native_unlock() const { return (_suspend_flags & _critical_native_unlock) != 0; } 457 458 inline void set_critical_native_unlock(); 459 inline void clear_critical_native_unlock(); 460 461 inline void set_trace_flag(); 462 inline void clear_trace_flag(); 463 464 // Support for Unhandled Oop detection 465 // Add the field for both, fastdebug and debug, builds to keep 466 // Thread's fields layout the same. 467 // Note: CHECK_UNHANDLED_OOPS is defined only for fastdebug build. 468 #ifdef CHECK_UNHANDLED_OOPS 469 private: 470 UnhandledOops* _unhandled_oops; 471 #elif defined(ASSERT) 472 private: 473 void* _unhandled_oops; 474 #endif 475 #ifdef CHECK_UNHANDLED_OOPS 476 public: 477 UnhandledOops* unhandled_oops() { return _unhandled_oops; } 478 // Mark oop safe for gc. It may be stack allocated but won't move. 479 void allow_unhandled_oop(oop *op) { 480 if (CheckUnhandledOops) unhandled_oops()->allow_unhandled_oop(op); 481 } 482 // Clear oops at safepoint so crashes point to unhandled oop violator 483 void clear_unhandled_oops() { 484 if (CheckUnhandledOops) unhandled_oops()->clear_unhandled_oops(); 485 } 486 #endif // CHECK_UNHANDLED_OOPS 487 488 public: 489 #ifndef PRODUCT 490 bool skip_gcalot() { return _skip_gcalot; } 491 void set_skip_gcalot(bool v) { _skip_gcalot = v; } 492 #endif 493 494 // Installs a pending exception to be inserted later 495 static void send_async_exception(oop thread_oop, oop java_throwable); 496 497 // Resource area 498 ResourceArea* resource_area() const { return _resource_area; } 499 void set_resource_area(ResourceArea* area) { _resource_area = area; } 500 501 OSThread* osthread() const { return _osthread; } 502 void set_osthread(OSThread* thread) { _osthread = thread; } 503 504 // JNI handle support 505 JNIHandleBlock* active_handles() const { return _active_handles; } 506 void set_active_handles(JNIHandleBlock* block) { _active_handles = block; } 507 JNIHandleBlock* free_handle_block() const { return _free_handle_block; } 508 void set_free_handle_block(JNIHandleBlock* block) { _free_handle_block = block; } 509 510 // Internal handle support 511 HandleArea* handle_area() const { return _handle_area; } 512 void set_handle_area(HandleArea* area) { _handle_area = area; } 513 514 GrowableArray<Metadata*>* metadata_handles() const { return _metadata_handles; } 515 void set_metadata_handles(GrowableArray<Metadata*>* handles){ _metadata_handles = handles; } 516 517 // Thread-Local Allocation Buffer (TLAB) support 518 ThreadLocalAllocBuffer& tlab() { return _tlab; } 519 void initialize_tlab() { 520 if (UseTLAB) { 521 tlab().initialize(); 522 } 523 } 524 525 jlong allocated_bytes() { return _allocated_bytes; } 526 void set_allocated_bytes(jlong value) { _allocated_bytes = value; } 527 void incr_allocated_bytes(jlong size) { _allocated_bytes += size; } 528 inline jlong cooked_allocated_bytes(); 529 530 ThreadHeapSampler& heap_sampler() { return _heap_sampler; } 531 532 ThreadStatisticalInfo& statistical_info() { return _statistical_info; } 533 534 JFR_ONLY(DEFINE_THREAD_LOCAL_ACCESSOR_JFR;) 535 536 bool is_trace_suspend() { return (_suspend_flags & _trace_flag) != 0; } 537 538 // VM operation support 539 int vm_operation_ticket() { return ++_vm_operation_started_count; } 540 int vm_operation_completed_count() { return _vm_operation_completed_count; } 541 void increment_vm_operation_completed_count() { _vm_operation_completed_count++; } 542 543 // For tracking the heavyweight monitor the thread is pending on. 544 ObjectMonitor* current_pending_monitor() { 545 return _current_pending_monitor; 546 } 547 void set_current_pending_monitor(ObjectMonitor* monitor) { 548 _current_pending_monitor = monitor; 549 } 550 void set_current_pending_monitor_is_from_java(bool from_java) { 551 _current_pending_monitor_is_from_java = from_java; 552 } 553 bool current_pending_monitor_is_from_java() { 554 return _current_pending_monitor_is_from_java; 555 } 556 557 // For tracking the ObjectMonitor on which this thread called Object.wait() 558 ObjectMonitor* current_waiting_monitor() { 559 return _current_waiting_monitor; 560 } 561 void set_current_waiting_monitor(ObjectMonitor* monitor) { 562 _current_waiting_monitor = monitor; 563 } 564 565 // GC support 566 // Apply "f->do_oop" to all root oops in "this". 567 // Used by JavaThread::oops_do. 568 // Apply "cf->do_code_blob" (if !NULL) to all code blobs active in frames 569 virtual void oops_do(OopClosure* f, CodeBlobClosure* cf); 570 571 // Handles the parallel case for the method below. 572 private: 573 bool claim_oops_do_par_case(int collection_parity); 574 public: 575 // Requires that "collection_parity" is that of the current roots 576 // iteration. If "is_par" is false, sets the parity of "this" to 577 // "collection_parity", and returns "true". If "is_par" is true, 578 // uses an atomic instruction to set the current threads parity to 579 // "collection_parity", if it is not already. Returns "true" iff the 580 // calling thread does the update, this indicates that the calling thread 581 // has claimed the thread's stack as a root groop in the current 582 // collection. 583 bool claim_oops_do(bool is_par, int collection_parity) { 584 if (!is_par) { 585 _oops_do_parity = collection_parity; 586 return true; 587 } else { 588 return claim_oops_do_par_case(collection_parity); 589 } 590 } 591 592 // jvmtiRedefineClasses support 593 void metadata_handles_do(void f(Metadata*)); 594 595 // Used by fast lock support 596 virtual bool is_lock_owned(address adr) const; 597 598 // Check if address is in the stack of the thread (not just for locks). 599 // Warning: the method can only be used on the running thread 600 bool is_in_stack(address adr) const; 601 // Check if address is in the usable part of the stack (excludes protected 602 // guard pages) 603 bool is_in_usable_stack(address adr) const; 604 605 // Sets this thread as starting thread. Returns failure if thread 606 // creation fails due to lack of memory, too many threads etc. 607 bool set_as_starting_thread(); 608 609 protected: 610 // OS data associated with the thread 611 OSThread* _osthread; // Platform-specific thread information 612 613 // Thread local resource area for temporary allocation within the VM 614 ResourceArea* _resource_area; 615 616 DEBUG_ONLY(ResourceMark* _current_resource_mark;) 617 618 // Thread local handle area for allocation of handles within the VM 619 HandleArea* _handle_area; 620 GrowableArray<Metadata*>* _metadata_handles; 621 622 // Support for stack overflow handling, get_thread, etc. 623 address _stack_base; 624 size_t _stack_size; 625 uintptr_t _self_raw_id; // used by get_thread (mutable) 626 int _lgrp_id; 627 628 volatile void** polling_page_addr() { return &_polling_page; } 629 630 public: 631 // Stack overflow support 632 address stack_base() const { assert(_stack_base != NULL,"Sanity check"); return _stack_base; } 633 void set_stack_base(address base) { _stack_base = base; } 634 size_t stack_size() const { return _stack_size; } 635 void set_stack_size(size_t size) { _stack_size = size; } 636 address stack_end() const { return stack_base() - stack_size(); } 637 void record_stack_base_and_size(); 638 639 bool on_local_stack(address adr) const { 640 // QQQ this has knowledge of direction, ought to be a stack method 641 return (_stack_base >= adr && adr >= stack_end()); 642 } 643 644 uintptr_t self_raw_id() { return _self_raw_id; } 645 void set_self_raw_id(uintptr_t value) { _self_raw_id = value; } 646 647 int lgrp_id() const { return _lgrp_id; } 648 void set_lgrp_id(int value) { _lgrp_id = value; } 649 650 // Printing 651 void print_on(outputStream* st, bool print_extended_info) const; 652 virtual void print_on(outputStream* st) const { print_on(st, false); } 653 void print() const { print_on(tty); } 654 virtual void print_on_error(outputStream* st, char* buf, int buflen) const; 655 void print_value_on(outputStream* st) const; 656 657 // Debug-only code 658 #ifdef ASSERT 659 private: 660 // Deadlock detection support for Mutex locks. List of locks own by thread. 661 Monitor* _owned_locks; 662 // Mutex::set_owner_implementation is the only place where _owned_locks is modified, 663 // thus the friendship 664 friend class Mutex; 665 friend class Monitor; 666 667 public: 668 void print_owned_locks_on(outputStream* st) const; 669 void print_owned_locks() const { print_owned_locks_on(tty); } 670 Monitor* owned_locks() const { return _owned_locks; } 671 bool owns_locks() const { return owned_locks() != NULL; } 672 bool owns_locks_but_compiled_lock() const; 673 int oops_do_parity() const { return _oops_do_parity; } 674 675 // Deadlock detection 676 bool allow_allocation() { return _allow_allocation_count == 0; } 677 ResourceMark* current_resource_mark() { return _current_resource_mark; } 678 void set_current_resource_mark(ResourceMark* rm) { _current_resource_mark = rm; } 679 #endif 680 681 void check_for_valid_safepoint_state(bool potential_vm_operation) PRODUCT_RETURN; 682 683 private: 684 volatile int _jvmti_env_iteration_count; 685 686 public: 687 void entering_jvmti_env_iteration() { ++_jvmti_env_iteration_count; } 688 void leaving_jvmti_env_iteration() { --_jvmti_env_iteration_count; } 689 bool is_inside_jvmti_env_iteration() { return _jvmti_env_iteration_count > 0; } 690 691 // Code generation 692 static ByteSize exception_file_offset() { return byte_offset_of(Thread, _exception_file); } 693 static ByteSize exception_line_offset() { return byte_offset_of(Thread, _exception_line); } 694 static ByteSize active_handles_offset() { return byte_offset_of(Thread, _active_handles); } 695 696 static ByteSize stack_base_offset() { return byte_offset_of(Thread, _stack_base); } 697 static ByteSize stack_size_offset() { return byte_offset_of(Thread, _stack_size); } 698 699 static ByteSize polling_page_offset() { return byte_offset_of(Thread, _polling_page); } 700 701 static ByteSize tlab_start_offset() { return byte_offset_of(Thread, _tlab) + ThreadLocalAllocBuffer::start_offset(); } 702 static ByteSize tlab_end_offset() { return byte_offset_of(Thread, _tlab) + ThreadLocalAllocBuffer::end_offset(); } 703 static ByteSize tlab_top_offset() { return byte_offset_of(Thread, _tlab) + ThreadLocalAllocBuffer::top_offset(); } 704 static ByteSize tlab_pf_top_offset() { return byte_offset_of(Thread, _tlab) + ThreadLocalAllocBuffer::pf_top_offset(); } 705 706 static ByteSize allocated_bytes_offset() { return byte_offset_of(Thread, _allocated_bytes); } 707 708 JFR_ONLY(DEFINE_THREAD_LOCAL_OFFSET_JFR;) 709 710 public: 711 volatile intptr_t _Stalled; 712 volatile int _TypeTag; 713 ParkEvent * _ParkEvent; // for synchronized() 714 ParkEvent * _SleepEvent; // for Thread.sleep 715 ParkEvent * _MutexEvent; // for native internal Mutex/Monitor 716 ParkEvent * _MuxEvent; // for low-level muxAcquire-muxRelease 717 int NativeSyncRecursion; // diagnostic 718 719 volatile int _OnTrap; // Resume-at IP delta 720 jint _hashStateW; // Marsaglia Shift-XOR thread-local RNG 721 jint _hashStateX; // thread-specific hashCode generator state 722 jint _hashStateY; 723 jint _hashStateZ; 724 725 volatile jint rng[4]; // RNG for spin loop 726 727 // Low-level leaf-lock primitives used to implement synchronization 728 // and native monitor-mutex infrastructure. 729 // Not for general synchronization use. 730 static void SpinAcquire(volatile int * Lock, const char * Name); 731 static void SpinRelease(volatile int * Lock); 732 static void muxAcquire(volatile intptr_t * Lock, const char * Name); 733 static void muxAcquireW(volatile intptr_t * Lock, ParkEvent * ev); 734 static void muxRelease(volatile intptr_t * Lock); 735 }; 736 737 // Inline implementation of Thread::current() 738 inline Thread* Thread::current() { 739 Thread* current = current_or_null(); 740 assert(current != NULL, "Thread::current() called on detached thread"); 741 return current; 742 } 743 744 inline Thread* Thread::current_or_null() { 745 #ifndef USE_LIBRARY_BASED_TLS_ONLY 746 return _thr_current; 747 #else 748 if (ThreadLocalStorage::is_initialized()) { 749 return ThreadLocalStorage::thread(); 750 } 751 return NULL; 752 #endif 753 } 754 755 inline Thread* Thread::current_or_null_safe() { 756 if (ThreadLocalStorage::is_initialized()) { 757 return ThreadLocalStorage::thread(); 758 } 759 return NULL; 760 } 761 762 class NonJavaThread: public Thread { 763 friend class VMStructs; 764 765 NonJavaThread* volatile _next; 766 767 class List; 768 static List _the_list; 769 770 public: 771 NonJavaThread(); 772 ~NonJavaThread(); 773 774 class Iterator; 775 }; 776 777 // Provides iteration over the list of NonJavaThreads. Because list 778 // management occurs in the NonJavaThread constructor and destructor, 779 // entries in the list may not be fully constructed instances of a 780 // derived class. Threads created after an iterator is constructed 781 // will not be visited by the iterator. The scope of an iterator is a 782 // critical section; there must be no safepoint checks in that scope. 783 class NonJavaThread::Iterator : public StackObj { 784 uint _protect_enter; 785 NonJavaThread* _current; 786 787 // Noncopyable. 788 Iterator(const Iterator&); 789 Iterator& operator=(const Iterator&); 790 791 public: 792 Iterator(); 793 ~Iterator(); 794 795 bool end() const { return _current == NULL; } 796 NonJavaThread* current() const { return _current; } 797 void step(); 798 }; 799 800 // Name support for threads. non-JavaThread subclasses with multiple 801 // uniquely named instances should derive from this. 802 class NamedThread: public NonJavaThread { 803 friend class VMStructs; 804 enum { 805 max_name_len = 64 806 }; 807 private: 808 char* _name; 809 // log JavaThread being processed by oops_do 810 JavaThread* _processed_thread; 811 uint _gc_id; // The current GC id when a thread takes part in GC 812 813 public: 814 NamedThread(); 815 ~NamedThread(); 816 // May only be called once per thread. 817 void set_name(const char* format, ...) ATTRIBUTE_PRINTF(2, 3); 818 void initialize_named_thread(); 819 virtual bool is_Named_thread() const { return true; } 820 virtual char* name() const { return _name == NULL ? (char*)"Unknown Thread" : _name; } 821 JavaThread *processed_thread() { return _processed_thread; } 822 void set_processed_thread(JavaThread *thread) { _processed_thread = thread; } 823 virtual void print_on(outputStream* st) const; 824 825 void set_gc_id(uint gc_id) { _gc_id = gc_id; } 826 uint gc_id() { return _gc_id; } 827 }; 828 829 // Worker threads are named and have an id of an assigned work. 830 class WorkerThread: public NamedThread { 831 private: 832 uint _id; 833 public: 834 WorkerThread() : _id(0) { } 835 virtual bool is_Worker_thread() const { return true; } 836 837 virtual WorkerThread* as_Worker_thread() const { 838 assert(is_Worker_thread(), "Dubious cast to WorkerThread*?"); 839 return (WorkerThread*) this; 840 } 841 842 void set_id(uint work_id) { _id = work_id; } 843 uint id() const { return _id; } 844 }; 845 846 // A single WatcherThread is used for simulating timer interrupts. 847 class WatcherThread: public NonJavaThread { 848 friend class VMStructs; 849 public: 850 virtual void run(); 851 852 private: 853 static WatcherThread* _watcher_thread; 854 855 static bool _startable; 856 // volatile due to at least one lock-free read 857 volatile static bool _should_terminate; 858 public: 859 enum SomeConstants { 860 delay_interval = 10 // interrupt delay in milliseconds 861 }; 862 863 // Constructor 864 WatcherThread(); 865 866 // No destruction allowed 867 ~WatcherThread() { 868 guarantee(false, "WatcherThread deletion must fix the race with VM termination"); 869 } 870 871 // Tester 872 bool is_Watcher_thread() const { return true; } 873 874 // Printing 875 char* name() const { return (char*)"VM Periodic Task Thread"; } 876 void print_on(outputStream* st) const; 877 void unpark(); 878 879 // Returns the single instance of WatcherThread 880 static WatcherThread* watcher_thread() { return _watcher_thread; } 881 882 // Create and start the single instance of WatcherThread, or stop it on shutdown 883 static void start(); 884 static void stop(); 885 // Only allow start once the VM is sufficiently initialized 886 // Otherwise the first task to enroll will trigger the start 887 static void make_startable(); 888 private: 889 int sleep() const; 890 }; 891 892 893 class CompilerThread; 894 895 typedef void (*ThreadFunction)(JavaThread*, TRAPS); 896 897 class JavaThread: public Thread { 898 friend class VMStructs; 899 friend class JVMCIVMStructs; 900 friend class WhiteBox; 901 private: 902 JavaThread* _next; // The next thread in the Threads list 903 bool _on_thread_list; // Is set when this JavaThread is added to the Threads list 904 oop _threadObj; // The Java level thread object 905 906 #ifdef ASSERT 907 private: 908 int _java_call_counter; 909 910 public: 911 int java_call_counter() { return _java_call_counter; } 912 void inc_java_call_counter() { _java_call_counter++; } 913 void dec_java_call_counter() { 914 assert(_java_call_counter > 0, "Invalid nesting of JavaCallWrapper"); 915 _java_call_counter--; 916 } 917 private: // restore original namespace restriction 918 #endif // ifdef ASSERT 919 920 #ifndef PRODUCT 921 public: 922 enum { 923 jump_ring_buffer_size = 16 924 }; 925 private: // restore original namespace restriction 926 #endif 927 928 JavaFrameAnchor _anchor; // Encapsulation of current java frame and it state 929 930 ThreadFunction _entry_point; 931 932 JNIEnv _jni_environment; 933 934 // Deopt support 935 DeoptResourceMark* _deopt_mark; // Holds special ResourceMark for deoptimization 936 937 intptr_t* _must_deopt_id; // id of frame that needs to be deopted once we 938 // transition out of native 939 CompiledMethod* _deopt_nmethod; // CompiledMethod that is currently being deoptimized 940 vframeArray* _vframe_array_head; // Holds the heap of the active vframeArrays 941 vframeArray* _vframe_array_last; // Holds last vFrameArray we popped 942 // Because deoptimization is lazy we must save jvmti requests to set locals 943 // in compiled frames until we deoptimize and we have an interpreter frame. 944 // This holds the pointer to array (yeah like there might be more than one) of 945 // description of compiled vframes that have locals that need to be updated. 946 GrowableArray<jvmtiDeferredLocalVariableSet*>* _deferred_locals_updates; 947 948 // Handshake value for fixing 6243940. We need a place for the i2c 949 // adapter to store the callee Method*. This value is NEVER live 950 // across a gc point so it does NOT have to be gc'd 951 // The handshake is open ended since we can't be certain that it will 952 // be NULLed. This is because we rarely ever see the race and end up 953 // in handle_wrong_method which is the backend of the handshake. See 954 // code in i2c adapters and handle_wrong_method. 955 956 Method* _callee_target; 957 958 // Used to pass back results to the interpreter or generated code running Java code. 959 oop _vm_result; // oop result is GC-preserved 960 Metadata* _vm_result_2; // non-oop result 961 962 // See ReduceInitialCardMarks: this holds the precise space interval of 963 // the most recent slow path allocation for which compiled code has 964 // elided card-marks for performance along the fast-path. 965 MemRegion _deferred_card_mark; 966 967 MonitorChunk* _monitor_chunks; // Contains the off stack monitors 968 // allocated during deoptimization 969 // and by JNI_MonitorEnter/Exit 970 971 // Async. requests support 972 enum AsyncRequests { 973 _no_async_condition = 0, 974 _async_exception, 975 _async_unsafe_access_error 976 }; 977 AsyncRequests _special_runtime_exit_condition; // Enum indicating pending async. request 978 oop _pending_async_exception; 979 980 // Safepoint support 981 public: // Expose _thread_state for SafeFetchInt() 982 volatile JavaThreadState _thread_state; 983 private: 984 ThreadSafepointState *_safepoint_state; // Holds information about a thread during a safepoint 985 address _saved_exception_pc; // Saved pc of instruction where last implicit exception happened 986 987 // JavaThread termination support 988 enum TerminatedTypes { 989 _not_terminated = 0xDEAD - 2, 990 _thread_exiting, // JavaThread::exit() has been called for this thread 991 _thread_terminated, // JavaThread is removed from thread list 992 _vm_exited // JavaThread is still executing native code, but VM is terminated 993 // only VM_Exit can set _vm_exited 994 }; 995 996 // In general a JavaThread's _terminated field transitions as follows: 997 // 998 // _not_terminated => _thread_exiting => _thread_terminated 999 // 1000 // _vm_exited is a special value to cover the case of a JavaThread 1001 // executing native code after the VM itself is terminated. 1002 volatile TerminatedTypes _terminated; 1003 // suspend/resume support 1004 volatile bool _suspend_equivalent; // Suspend equivalent condition 1005 jint _in_deopt_handler; // count of deoptimization 1006 // handlers thread is in 1007 volatile bool _doing_unsafe_access; // Thread may fault due to unsafe access 1008 bool _do_not_unlock_if_synchronized; // Do not unlock the receiver of a synchronized method (since it was 1009 // never locked) when throwing an exception. Used by interpreter only. 1010 1011 // JNI attach states: 1012 enum JNIAttachStates { 1013 _not_attaching_via_jni = 1, // thread is not attaching via JNI 1014 _attaching_via_jni, // thread is attaching via JNI 1015 _attached_via_jni // thread has attached via JNI 1016 }; 1017 1018 // A regular JavaThread's _jni_attach_state is _not_attaching_via_jni. 1019 // A native thread that is attaching via JNI starts with a value 1020 // of _attaching_via_jni and transitions to _attached_via_jni. 1021 volatile JNIAttachStates _jni_attach_state; 1022 1023 public: 1024 // State of the stack guard pages for this thread. 1025 enum StackGuardState { 1026 stack_guard_unused, // not needed 1027 stack_guard_reserved_disabled, 1028 stack_guard_yellow_reserved_disabled,// disabled (temporarily) after stack overflow 1029 stack_guard_enabled // enabled 1030 }; 1031 1032 private: 1033 1034 #if INCLUDE_JVMCI 1035 // The _pending_* fields below are used to communicate extra information 1036 // from an uncommon trap in JVMCI compiled code to the uncommon trap handler. 1037 1038 // Communicates the DeoptReason and DeoptAction of the uncommon trap 1039 int _pending_deoptimization; 1040 1041 // Specifies whether the uncommon trap is to bci 0 of a synchronized method 1042 // before the monitor has been acquired. 1043 bool _pending_monitorenter; 1044 1045 // Specifies if the DeoptReason for the last uncommon trap was Reason_transfer_to_interpreter 1046 bool _pending_transfer_to_interpreter; 1047 1048 // Guard for re-entrant call to JVMCIRuntime::adjust_comp_level 1049 bool _adjusting_comp_level; 1050 1051 // An id of a speculation that JVMCI compiled code can use to further describe and 1052 // uniquely identify the speculative optimization guarded by the uncommon trap 1053 long _pending_failed_speculation; 1054 1055 // These fields are mutually exclusive in terms of live ranges. 1056 union { 1057 // Communicates the pc at which the most recent implicit exception occurred 1058 // from the signal handler to a deoptimization stub. 1059 address _implicit_exception_pc; 1060 1061 // Communicates an alternative call target to an i2c stub from a JavaCall . 1062 address _alternate_call_target; 1063 } _jvmci; 1064 1065 // Support for high precision, thread sensitive counters in JVMCI compiled code. 1066 jlong* _jvmci_counters; 1067 1068 public: 1069 static jlong* _jvmci_old_thread_counters; 1070 static void collect_counters(typeArrayOop array); 1071 private: 1072 #endif // INCLUDE_JVMCI 1073 1074 StackGuardState _stack_guard_state; 1075 1076 // Precompute the limit of the stack as used in stack overflow checks. 1077 // We load it from here to simplify the stack overflow check in assembly. 1078 address _stack_overflow_limit; 1079 address _reserved_stack_activation; 1080 1081 #ifdef _WIN64 1082 // On windows, in the stubGenerator, there's nowhere to save callee saved regs 1083 address _windows_saved_rsi; 1084 address _windows_saved_rdi; 1085 #endif // _WIN64 1086 1087 // Compiler exception handling (NOTE: The _exception_oop is *NOT* the same as _pending_exception. It is 1088 // used to temp. parsing values into and out of the runtime system during exception handling for compiled 1089 // code) 1090 volatile oop _exception_oop; // Exception thrown in compiled code 1091 volatile address _exception_pc; // PC where exception happened 1092 volatile address _exception_handler_pc; // PC for handler of exception 1093 volatile int _is_method_handle_return; // true (== 1) if the current exception PC is a MethodHandle call site. 1094 1095 private: 1096 // support for JNI critical regions 1097 jint _jni_active_critical; // count of entries into JNI critical region 1098 1099 // Checked JNI: function name requires exception check 1100 char* _pending_jni_exception_check_fn; 1101 1102 // For deadlock detection. 1103 int _depth_first_number; 1104 1105 // JVMTI PopFrame support 1106 // This is set to popframe_pending to signal that top Java frame should be popped immediately 1107 int _popframe_condition; 1108 1109 // If reallocation of scalar replaced objects fails, we throw OOM 1110 // and during exception propagation, pop the top 1111 // _frames_to_pop_failed_realloc frames, the ones that reference 1112 // failed reallocations. 1113 int _frames_to_pop_failed_realloc; 1114 1115 #ifndef PRODUCT 1116 int _jmp_ring_index; 1117 struct { 1118 // We use intptr_t instead of address so debugger doesn't try and display strings 1119 intptr_t _target; 1120 intptr_t _instruction; 1121 const char* _file; 1122 int _line; 1123 } _jmp_ring[jump_ring_buffer_size]; 1124 #endif // PRODUCT 1125 1126 friend class VMThread; 1127 friend class ThreadWaitTransition; 1128 friend class VM_Exit; 1129 1130 void initialize(); // Initialized the instance variables 1131 1132 public: 1133 // Constructor 1134 JavaThread(bool is_attaching_via_jni = false); // for main thread and JNI attached threads 1135 JavaThread(ThreadFunction entry_point, size_t stack_size = 0); 1136 ~JavaThread(); 1137 1138 #ifdef ASSERT 1139 // verify this JavaThread hasn't be published in the Threads::list yet 1140 void verify_not_published(); 1141 #endif 1142 1143 //JNI functiontable getter/setter for JVMTI jni function table interception API. 1144 void set_jni_functions(struct JNINativeInterface_* functionTable) { 1145 _jni_environment.functions = functionTable; 1146 } 1147 struct JNINativeInterface_* get_jni_functions() { 1148 return (struct JNINativeInterface_ *)_jni_environment.functions; 1149 } 1150 1151 // This function is called at thread creation to allow 1152 // platform specific thread variables to be initialized. 1153 void cache_global_variables(); 1154 1155 // Executes Shutdown.shutdown() 1156 void invoke_shutdown_hooks(); 1157 1158 // Cleanup on thread exit 1159 enum ExitType { 1160 normal_exit, 1161 jni_detach 1162 }; 1163 void exit(bool destroy_vm, ExitType exit_type = normal_exit); 1164 1165 void cleanup_failed_attach_current_thread(); 1166 1167 // Testers 1168 virtual bool is_Java_thread() const { return true; } 1169 virtual bool can_call_java() const { return true; } 1170 1171 // Thread chain operations 1172 JavaThread* next() const { return _next; } 1173 void set_next(JavaThread* p) { _next = p; } 1174 1175 // Thread oop. threadObj() can be NULL for initial JavaThread 1176 // (or for threads attached via JNI) 1177 oop threadObj() const { return _threadObj; } 1178 void set_threadObj(oop p) { _threadObj = p; } 1179 1180 ThreadPriority java_priority() const; // Read from threadObj() 1181 1182 // Prepare thread and add to priority queue. If a priority is 1183 // not specified, use the priority of the thread object. Threads_lock 1184 // must be held while this function is called. 1185 void prepare(jobject jni_thread, ThreadPriority prio=NoPriority); 1186 1187 void set_saved_exception_pc(address pc) { _saved_exception_pc = pc; } 1188 address saved_exception_pc() { return _saved_exception_pc; } 1189 1190 1191 ThreadFunction entry_point() const { return _entry_point; } 1192 1193 // Allocates a new Java level thread object for this thread. thread_name may be NULL. 1194 void allocate_threadObj(Handle thread_group, const char* thread_name, bool daemon, TRAPS); 1195 1196 // Last frame anchor routines 1197 1198 JavaFrameAnchor* frame_anchor(void) { return &_anchor; } 1199 1200 // last_Java_sp 1201 bool has_last_Java_frame() const { return _anchor.has_last_Java_frame(); } 1202 intptr_t* last_Java_sp() const { return _anchor.last_Java_sp(); } 1203 1204 // last_Java_pc 1205 1206 address last_Java_pc(void) { return _anchor.last_Java_pc(); } 1207 1208 // Safepoint support 1209 #if !(defined(PPC64) || defined(AARCH64)) 1210 JavaThreadState thread_state() const { return _thread_state; } 1211 void set_thread_state(JavaThreadState s) { _thread_state = s; } 1212 #else 1213 // Use membars when accessing volatile _thread_state. See 1214 // Threads::create_vm() for size checks. 1215 inline JavaThreadState thread_state() const; 1216 inline void set_thread_state(JavaThreadState s); 1217 #endif 1218 ThreadSafepointState *safepoint_state() const { return _safepoint_state; } 1219 void set_safepoint_state(ThreadSafepointState *state) { _safepoint_state = state; } 1220 bool is_at_poll_safepoint() { return _safepoint_state->is_at_poll_safepoint(); } 1221 1222 // JavaThread termination and lifecycle support: 1223 void smr_delete(); 1224 bool on_thread_list() const { return _on_thread_list; } 1225 void set_on_thread_list() { _on_thread_list = true; } 1226 1227 // thread has called JavaThread::exit() or is terminated 1228 bool is_exiting() const; 1229 // thread is terminated (no longer on the threads list); we compare 1230 // against the two non-terminated values so that a freed JavaThread 1231 // will also be considered terminated. 1232 bool check_is_terminated(TerminatedTypes l_terminated) const { 1233 return l_terminated != _not_terminated && l_terminated != _thread_exiting; 1234 } 1235 bool is_terminated() const; 1236 void set_terminated(TerminatedTypes t); 1237 // special for Threads::remove() which is static: 1238 void set_terminated_value(); 1239 void block_if_vm_exited(); 1240 1241 bool doing_unsafe_access() { return _doing_unsafe_access; } 1242 void set_doing_unsafe_access(bool val) { _doing_unsafe_access = val; } 1243 1244 bool do_not_unlock_if_synchronized() { return _do_not_unlock_if_synchronized; } 1245 void set_do_not_unlock_if_synchronized(bool val) { _do_not_unlock_if_synchronized = val; } 1246 1247 inline void set_polling_page_release(void* poll_value); 1248 inline void set_polling_page(void* poll_value); 1249 inline volatile void* get_polling_page(); 1250 1251 private: 1252 // Support for thread handshake operations 1253 HandshakeState _handshake; 1254 public: 1255 void set_handshake_operation(HandshakeOperation* op) { 1256 _handshake.set_operation(this, op); 1257 } 1258 1259 bool has_handshake() const { 1260 return _handshake.has_operation(); 1261 } 1262 1263 void cancel_handshake() { 1264 _handshake.cancel(this); 1265 } 1266 1267 void handshake_process_by_self() { 1268 _handshake.process_by_self(this); 1269 } 1270 1271 void handshake_process_by_vmthread() { 1272 _handshake.process_by_vmthread(this); 1273 } 1274 1275 // Suspend/resume support for JavaThread 1276 private: 1277 inline void set_ext_suspended(); 1278 inline void clear_ext_suspended(); 1279 1280 public: 1281 void java_suspend(); 1282 void java_resume(); 1283 int java_suspend_self(); 1284 1285 void check_and_wait_while_suspended() { 1286 assert(JavaThread::current() == this, "sanity check"); 1287 1288 bool do_self_suspend; 1289 do { 1290 // were we externally suspended while we were waiting? 1291 do_self_suspend = handle_special_suspend_equivalent_condition(); 1292 if (do_self_suspend) { 1293 // don't surprise the thread that suspended us by returning 1294 java_suspend_self(); 1295 set_suspend_equivalent(); 1296 } 1297 } while (do_self_suspend); 1298 } 1299 static void check_safepoint_and_suspend_for_native_trans(JavaThread *thread); 1300 // Check for async exception in addition to safepoint and suspend request. 1301 static void check_special_condition_for_native_trans(JavaThread *thread); 1302 1303 // Same as check_special_condition_for_native_trans but finishes the 1304 // transition into thread_in_Java mode so that it can potentially 1305 // block. 1306 static void check_special_condition_for_native_trans_and_transition(JavaThread *thread); 1307 1308 bool is_ext_suspend_completed(bool called_by_wait, int delay, uint32_t *bits); 1309 bool is_ext_suspend_completed_with_lock(uint32_t *bits) { 1310 MutexLockerEx ml(SR_lock(), Mutex::_no_safepoint_check_flag); 1311 // Warning: is_ext_suspend_completed() may temporarily drop the 1312 // SR_lock to allow the thread to reach a stable thread state if 1313 // it is currently in a transient thread state. 1314 return is_ext_suspend_completed(false /* !called_by_wait */, 1315 SuspendRetryDelay, bits); 1316 } 1317 1318 // We cannot allow wait_for_ext_suspend_completion() to run forever or 1319 // we could hang. SuspendRetryCount and SuspendRetryDelay are normally 1320 // passed as the count and delay parameters. Experiments with specific 1321 // calls to wait_for_ext_suspend_completion() can be done by passing 1322 // other values in the code. Experiments with all calls can be done 1323 // via the appropriate -XX options. 1324 bool wait_for_ext_suspend_completion(int count, int delay, uint32_t *bits); 1325 1326 // test for suspend - most (all?) of these should go away 1327 bool is_thread_fully_suspended(bool wait_for_suspend, uint32_t *bits); 1328 1329 inline void set_external_suspend(); 1330 inline void clear_external_suspend(); 1331 1332 inline void set_deopt_suspend(); 1333 inline void clear_deopt_suspend(); 1334 bool is_deopt_suspend() { return (_suspend_flags & _deopt_suspend) != 0; } 1335 1336 bool is_external_suspend() const { 1337 return (_suspend_flags & _external_suspend) != 0; 1338 } 1339 // Whenever a thread transitions from native to vm/java it must suspend 1340 // if external|deopt suspend is present. 1341 bool is_suspend_after_native() const { 1342 return (_suspend_flags & (_external_suspend | _deopt_suspend)) != 0; 1343 } 1344 1345 // external suspend request is completed 1346 bool is_ext_suspended() const { 1347 return (_suspend_flags & _ext_suspended) != 0; 1348 } 1349 1350 bool is_external_suspend_with_lock() const { 1351 MutexLockerEx ml(SR_lock(), Mutex::_no_safepoint_check_flag); 1352 return is_external_suspend(); 1353 } 1354 1355 // Special method to handle a pending external suspend request 1356 // when a suspend equivalent condition lifts. 1357 bool handle_special_suspend_equivalent_condition() { 1358 assert(is_suspend_equivalent(), 1359 "should only be called in a suspend equivalence condition"); 1360 MutexLockerEx ml(SR_lock(), Mutex::_no_safepoint_check_flag); 1361 bool ret = is_external_suspend(); 1362 if (!ret) { 1363 // not about to self-suspend so clear suspend equivalence 1364 clear_suspend_equivalent(); 1365 } 1366 // implied else: 1367 // We have a pending external suspend request so we leave the 1368 // suspend_equivalent flag set until java_suspend_self() sets 1369 // the ext_suspended flag and clears the suspend_equivalent 1370 // flag. This insures that wait_for_ext_suspend_completion() 1371 // will return consistent values. 1372 return ret; 1373 } 1374 1375 // utility methods to see if we are doing some kind of suspension 1376 bool is_being_ext_suspended() const { 1377 MutexLockerEx ml(SR_lock(), Mutex::_no_safepoint_check_flag); 1378 return is_ext_suspended() || is_external_suspend(); 1379 } 1380 1381 bool is_suspend_equivalent() const { return _suspend_equivalent; } 1382 1383 void set_suspend_equivalent() { _suspend_equivalent = true; } 1384 void clear_suspend_equivalent() { _suspend_equivalent = false; } 1385 1386 // Thread.stop support 1387 void send_thread_stop(oop throwable); 1388 AsyncRequests clear_special_runtime_exit_condition() { 1389 AsyncRequests x = _special_runtime_exit_condition; 1390 _special_runtime_exit_condition = _no_async_condition; 1391 return x; 1392 } 1393 1394 // Are any async conditions present? 1395 bool has_async_condition() { return (_special_runtime_exit_condition != _no_async_condition); } 1396 1397 void check_and_handle_async_exceptions(bool check_unsafe_error = true); 1398 1399 // these next two are also used for self-suspension and async exception support 1400 void handle_special_runtime_exit_condition(bool check_asyncs = true); 1401 1402 // Return true if JavaThread has an asynchronous condition or 1403 // if external suspension is requested. 1404 bool has_special_runtime_exit_condition() { 1405 // Because we don't use is_external_suspend_with_lock 1406 // it is possible that we won't see an asynchronous external suspend 1407 // request that has just gotten started, i.e., SR_lock grabbed but 1408 // _external_suspend field change either not made yet or not visible 1409 // yet. However, this is okay because the request is asynchronous and 1410 // we will see the new flag value the next time through. It's also 1411 // possible that the external suspend request is dropped after 1412 // we have checked is_external_suspend(), we will recheck its value 1413 // under SR_lock in java_suspend_self(). 1414 return (_special_runtime_exit_condition != _no_async_condition) || 1415 is_external_suspend() || is_trace_suspend(); 1416 } 1417 1418 void set_pending_unsafe_access_error() { _special_runtime_exit_condition = _async_unsafe_access_error; } 1419 1420 inline void set_pending_async_exception(oop e); 1421 1422 // Fast-locking support 1423 bool is_lock_owned(address adr) const; 1424 1425 // Accessors for vframe array top 1426 // The linked list of vframe arrays are sorted on sp. This means when we 1427 // unpack the head must contain the vframe array to unpack. 1428 void set_vframe_array_head(vframeArray* value) { _vframe_array_head = value; } 1429 vframeArray* vframe_array_head() const { return _vframe_array_head; } 1430 1431 // Side structure for deferring update of java frame locals until deopt occurs 1432 GrowableArray<jvmtiDeferredLocalVariableSet*>* deferred_locals() const { return _deferred_locals_updates; } 1433 void set_deferred_locals(GrowableArray<jvmtiDeferredLocalVariableSet *>* vf) { _deferred_locals_updates = vf; } 1434 1435 // These only really exist to make debugging deopt problems simpler 1436 1437 void set_vframe_array_last(vframeArray* value) { _vframe_array_last = value; } 1438 vframeArray* vframe_array_last() const { return _vframe_array_last; } 1439 1440 // The special resourceMark used during deoptimization 1441 1442 void set_deopt_mark(DeoptResourceMark* value) { _deopt_mark = value; } 1443 DeoptResourceMark* deopt_mark(void) { return _deopt_mark; } 1444 1445 intptr_t* must_deopt_id() { return _must_deopt_id; } 1446 void set_must_deopt_id(intptr_t* id) { _must_deopt_id = id; } 1447 void clear_must_deopt_id() { _must_deopt_id = NULL; } 1448 1449 void set_deopt_compiled_method(CompiledMethod* nm) { _deopt_nmethod = nm; } 1450 CompiledMethod* deopt_compiled_method() { return _deopt_nmethod; } 1451 1452 Method* callee_target() const { return _callee_target; } 1453 void set_callee_target (Method* x) { _callee_target = x; } 1454 1455 // Oop results of vm runtime calls 1456 oop vm_result() const { return _vm_result; } 1457 void set_vm_result (oop x) { _vm_result = x; } 1458 1459 Metadata* vm_result_2() const { return _vm_result_2; } 1460 void set_vm_result_2 (Metadata* x) { _vm_result_2 = x; } 1461 1462 MemRegion deferred_card_mark() const { return _deferred_card_mark; } 1463 void set_deferred_card_mark(MemRegion mr) { _deferred_card_mark = mr; } 1464 1465 #if INCLUDE_JVMCI 1466 int pending_deoptimization() const { return _pending_deoptimization; } 1467 long pending_failed_speculation() const { return _pending_failed_speculation; } 1468 bool adjusting_comp_level() const { return _adjusting_comp_level; } 1469 void set_adjusting_comp_level(bool b) { _adjusting_comp_level = b; } 1470 bool has_pending_monitorenter() const { return _pending_monitorenter; } 1471 void set_pending_monitorenter(bool b) { _pending_monitorenter = b; } 1472 void set_pending_deoptimization(int reason) { _pending_deoptimization = reason; } 1473 void set_pending_failed_speculation(long failed_speculation) { _pending_failed_speculation = failed_speculation; } 1474 void set_pending_transfer_to_interpreter(bool b) { _pending_transfer_to_interpreter = b; } 1475 void set_jvmci_alternate_call_target(address a) { assert(_jvmci._alternate_call_target == NULL, "must be"); _jvmci._alternate_call_target = a; } 1476 void set_jvmci_implicit_exception_pc(address a) { assert(_jvmci._implicit_exception_pc == NULL, "must be"); _jvmci._implicit_exception_pc = a; } 1477 #endif // INCLUDE_JVMCI 1478 1479 // Exception handling for compiled methods 1480 oop exception_oop() const { return _exception_oop; } 1481 address exception_pc() const { return _exception_pc; } 1482 address exception_handler_pc() const { return _exception_handler_pc; } 1483 bool is_method_handle_return() const { return _is_method_handle_return == 1; } 1484 1485 void set_exception_oop(oop o) { (void)const_cast<oop&>(_exception_oop = o); } 1486 void set_exception_pc(address a) { _exception_pc = a; } 1487 void set_exception_handler_pc(address a) { _exception_handler_pc = a; } 1488 void set_is_method_handle_return(bool value) { _is_method_handle_return = value ? 1 : 0; } 1489 1490 void clear_exception_oop_and_pc() { 1491 set_exception_oop(NULL); 1492 set_exception_pc(NULL); 1493 } 1494 1495 // Stack overflow support 1496 // 1497 // (small addresses) 1498 // 1499 // -- <-- stack_end() --- 1500 // | | 1501 // | red pages | 1502 // | | 1503 // -- <-- stack_red_zone_base() | 1504 // | | 1505 // | guard 1506 // | yellow pages zone 1507 // | | 1508 // | | 1509 // -- <-- stack_yellow_zone_base() | 1510 // | | 1511 // | | 1512 // | reserved pages | 1513 // | | 1514 // -- <-- stack_reserved_zone_base() --- --- 1515 // /|\ shadow <-- stack_overflow_limit() (somewhere in here) 1516 // | zone 1517 // \|/ size 1518 // some untouched memory --- 1519 // 1520 // 1521 // -- 1522 // | 1523 // | shadow zone 1524 // | 1525 // -- 1526 // x frame n 1527 // -- 1528 // x frame n-1 1529 // x 1530 // -- 1531 // ... 1532 // 1533 // -- 1534 // x frame 0 1535 // -- <-- stack_base() 1536 // 1537 // (large addresses) 1538 // 1539 1540 private: 1541 // These values are derived from flags StackRedPages, StackYellowPages, 1542 // StackReservedPages and StackShadowPages. The zone size is determined 1543 // ergonomically if page_size > 4K. 1544 static size_t _stack_red_zone_size; 1545 static size_t _stack_yellow_zone_size; 1546 static size_t _stack_reserved_zone_size; 1547 static size_t _stack_shadow_zone_size; 1548 public: 1549 inline size_t stack_available(address cur_sp); 1550 1551 static size_t stack_red_zone_size() { 1552 assert(_stack_red_zone_size > 0, "Don't call this before the field is initialized."); 1553 return _stack_red_zone_size; 1554 } 1555 static void set_stack_red_zone_size(size_t s) { 1556 assert(is_aligned(s, os::vm_page_size()), 1557 "We can not protect if the red zone size is not page aligned."); 1558 assert(_stack_red_zone_size == 0, "This should be called only once."); 1559 _stack_red_zone_size = s; 1560 } 1561 address stack_red_zone_base() { 1562 return (address)(stack_end() + stack_red_zone_size()); 1563 } 1564 bool in_stack_red_zone(address a) { 1565 return a <= stack_red_zone_base() && a >= stack_end(); 1566 } 1567 1568 static size_t stack_yellow_zone_size() { 1569 assert(_stack_yellow_zone_size > 0, "Don't call this before the field is initialized."); 1570 return _stack_yellow_zone_size; 1571 } 1572 static void set_stack_yellow_zone_size(size_t s) { 1573 assert(is_aligned(s, os::vm_page_size()), 1574 "We can not protect if the yellow zone size is not page aligned."); 1575 assert(_stack_yellow_zone_size == 0, "This should be called only once."); 1576 _stack_yellow_zone_size = s; 1577 } 1578 1579 static size_t stack_reserved_zone_size() { 1580 // _stack_reserved_zone_size may be 0. This indicates the feature is off. 1581 return _stack_reserved_zone_size; 1582 } 1583 static void set_stack_reserved_zone_size(size_t s) { 1584 assert(is_aligned(s, os::vm_page_size()), 1585 "We can not protect if the reserved zone size is not page aligned."); 1586 assert(_stack_reserved_zone_size == 0, "This should be called only once."); 1587 _stack_reserved_zone_size = s; 1588 } 1589 address stack_reserved_zone_base() { 1590 return (address)(stack_end() + 1591 (stack_red_zone_size() + stack_yellow_zone_size() + stack_reserved_zone_size())); 1592 } 1593 bool in_stack_reserved_zone(address a) { 1594 return (a <= stack_reserved_zone_base()) && 1595 (a >= (address)((intptr_t)stack_reserved_zone_base() - stack_reserved_zone_size())); 1596 } 1597 1598 static size_t stack_yellow_reserved_zone_size() { 1599 return _stack_yellow_zone_size + _stack_reserved_zone_size; 1600 } 1601 bool in_stack_yellow_reserved_zone(address a) { 1602 return (a <= stack_reserved_zone_base()) && (a >= stack_red_zone_base()); 1603 } 1604 1605 // Size of red + yellow + reserved zones. 1606 static size_t stack_guard_zone_size() { 1607 return stack_red_zone_size() + stack_yellow_reserved_zone_size(); 1608 } 1609 1610 static size_t stack_shadow_zone_size() { 1611 assert(_stack_shadow_zone_size > 0, "Don't call this before the field is initialized."); 1612 return _stack_shadow_zone_size; 1613 } 1614 static void set_stack_shadow_zone_size(size_t s) { 1615 // The shadow area is not allocated or protected, so 1616 // it needs not be page aligned. 1617 // But the stack bang currently assumes that it is a 1618 // multiple of page size. This guarantees that the bang 1619 // loop touches all pages in the shadow zone. 1620 // This can be guaranteed differently, as well. E.g., if 1621 // the page size is a multiple of 4K, banging in 4K steps 1622 // suffices to touch all pages. (Some pages are banged 1623 // several times, though.) 1624 assert(is_aligned(s, os::vm_page_size()), 1625 "Stack bang assumes multiple of page size."); 1626 assert(_stack_shadow_zone_size == 0, "This should be called only once."); 1627 _stack_shadow_zone_size = s; 1628 } 1629 1630 void create_stack_guard_pages(); 1631 void remove_stack_guard_pages(); 1632 1633 void enable_stack_reserved_zone(); 1634 void disable_stack_reserved_zone(); 1635 void enable_stack_yellow_reserved_zone(); 1636 void disable_stack_yellow_reserved_zone(); 1637 void enable_stack_red_zone(); 1638 void disable_stack_red_zone(); 1639 1640 inline bool stack_guard_zone_unused(); 1641 inline bool stack_yellow_reserved_zone_disabled(); 1642 inline bool stack_reserved_zone_disabled(); 1643 inline bool stack_guards_enabled(); 1644 1645 address reserved_stack_activation() const { return _reserved_stack_activation; } 1646 void set_reserved_stack_activation(address addr) { 1647 assert(_reserved_stack_activation == stack_base() 1648 || _reserved_stack_activation == NULL 1649 || addr == stack_base(), "Must not be set twice"); 1650 _reserved_stack_activation = addr; 1651 } 1652 1653 // Attempt to reguard the stack after a stack overflow may have occurred. 1654 // Returns true if (a) guard pages are not needed on this thread, (b) the 1655 // pages are already guarded, or (c) the pages were successfully reguarded. 1656 // Returns false if there is not enough stack space to reguard the pages, in 1657 // which case the caller should unwind a frame and try again. The argument 1658 // should be the caller's (approximate) sp. 1659 bool reguard_stack(address cur_sp); 1660 // Similar to above but see if current stackpoint is out of the guard area 1661 // and reguard if possible. 1662 bool reguard_stack(void); 1663 1664 address stack_overflow_limit() { return _stack_overflow_limit; } 1665 void set_stack_overflow_limit() { 1666 _stack_overflow_limit = 1667 stack_end() + MAX2(JavaThread::stack_guard_zone_size(), JavaThread::stack_shadow_zone_size()); 1668 } 1669 1670 // Misc. accessors/mutators 1671 void set_do_not_unlock(void) { _do_not_unlock_if_synchronized = true; } 1672 void clr_do_not_unlock(void) { _do_not_unlock_if_synchronized = false; } 1673 bool do_not_unlock(void) { return _do_not_unlock_if_synchronized; } 1674 1675 #ifndef PRODUCT 1676 void record_jump(address target, address instr, const char* file, int line); 1677 #endif // PRODUCT 1678 1679 // For assembly stub generation 1680 static ByteSize threadObj_offset() { return byte_offset_of(JavaThread, _threadObj); } 1681 #ifndef PRODUCT 1682 static ByteSize jmp_ring_index_offset() { return byte_offset_of(JavaThread, _jmp_ring_index); } 1683 static ByteSize jmp_ring_offset() { return byte_offset_of(JavaThread, _jmp_ring); } 1684 #endif // PRODUCT 1685 static ByteSize jni_environment_offset() { return byte_offset_of(JavaThread, _jni_environment); } 1686 static ByteSize pending_jni_exception_check_fn_offset() { 1687 return byte_offset_of(JavaThread, _pending_jni_exception_check_fn); 1688 } 1689 static ByteSize last_Java_sp_offset() { 1690 return byte_offset_of(JavaThread, _anchor) + JavaFrameAnchor::last_Java_sp_offset(); 1691 } 1692 static ByteSize last_Java_pc_offset() { 1693 return byte_offset_of(JavaThread, _anchor) + JavaFrameAnchor::last_Java_pc_offset(); 1694 } 1695 static ByteSize frame_anchor_offset() { 1696 return byte_offset_of(JavaThread, _anchor); 1697 } 1698 static ByteSize callee_target_offset() { return byte_offset_of(JavaThread, _callee_target); } 1699 static ByteSize vm_result_offset() { return byte_offset_of(JavaThread, _vm_result); } 1700 static ByteSize vm_result_2_offset() { return byte_offset_of(JavaThread, _vm_result_2); } 1701 static ByteSize thread_state_offset() { return byte_offset_of(JavaThread, _thread_state); } 1702 static ByteSize saved_exception_pc_offset() { return byte_offset_of(JavaThread, _saved_exception_pc); } 1703 static ByteSize osthread_offset() { return byte_offset_of(JavaThread, _osthread); } 1704 #if INCLUDE_JVMCI 1705 static ByteSize pending_deoptimization_offset() { return byte_offset_of(JavaThread, _pending_deoptimization); } 1706 static ByteSize pending_monitorenter_offset() { return byte_offset_of(JavaThread, _pending_monitorenter); } 1707 static ByteSize pending_failed_speculation_offset() { return byte_offset_of(JavaThread, _pending_failed_speculation); } 1708 static ByteSize jvmci_alternate_call_target_offset() { return byte_offset_of(JavaThread, _jvmci._alternate_call_target); } 1709 static ByteSize jvmci_implicit_exception_pc_offset() { return byte_offset_of(JavaThread, _jvmci._implicit_exception_pc); } 1710 static ByteSize jvmci_counters_offset() { return byte_offset_of(JavaThread, _jvmci_counters); } 1711 #endif // INCLUDE_JVMCI 1712 static ByteSize exception_oop_offset() { return byte_offset_of(JavaThread, _exception_oop); } 1713 static ByteSize exception_pc_offset() { return byte_offset_of(JavaThread, _exception_pc); } 1714 static ByteSize exception_handler_pc_offset() { return byte_offset_of(JavaThread, _exception_handler_pc); } 1715 static ByteSize stack_overflow_limit_offset() { return byte_offset_of(JavaThread, _stack_overflow_limit); } 1716 static ByteSize is_method_handle_return_offset() { return byte_offset_of(JavaThread, _is_method_handle_return); } 1717 static ByteSize stack_guard_state_offset() { return byte_offset_of(JavaThread, _stack_guard_state); } 1718 static ByteSize reserved_stack_activation_offset() { return byte_offset_of(JavaThread, _reserved_stack_activation); } 1719 static ByteSize suspend_flags_offset() { return byte_offset_of(JavaThread, _suspend_flags); } 1720 1721 static ByteSize do_not_unlock_if_synchronized_offset() { return byte_offset_of(JavaThread, _do_not_unlock_if_synchronized); } 1722 static ByteSize should_post_on_exceptions_flag_offset() { 1723 return byte_offset_of(JavaThread, _should_post_on_exceptions_flag); 1724 } 1725 1726 #ifdef _WIN64 1727 static ByteSize windows_saved_rsi_offset() { return byte_offset_of(JavaThread, _windows_saved_rsi); } 1728 static ByteSize windows_saved_rdi_offset() { return byte_offset_of(JavaThread, _windows_saved_rdi); } 1729 #endif // _WIN64 1730 1731 // Returns the jni environment for this thread 1732 JNIEnv* jni_environment() { return &_jni_environment; } 1733 1734 static JavaThread* thread_from_jni_environment(JNIEnv* env) { 1735 JavaThread *thread_from_jni_env = (JavaThread*)((intptr_t)env - in_bytes(jni_environment_offset())); 1736 // Only return NULL if thread is off the thread list; starting to 1737 // exit should not return NULL. 1738 if (thread_from_jni_env->is_terminated()) { 1739 thread_from_jni_env->block_if_vm_exited(); 1740 return NULL; 1741 } else { 1742 return thread_from_jni_env; 1743 } 1744 } 1745 1746 // JNI critical regions. These can nest. 1747 bool in_critical() { return _jni_active_critical > 0; } 1748 bool in_last_critical() { return _jni_active_critical == 1; } 1749 void enter_critical() { 1750 assert(Thread::current() == this || 1751 (Thread::current()->is_VM_thread() && 1752 SafepointSynchronize::is_synchronizing()), 1753 "this must be current thread or synchronizing"); 1754 _jni_active_critical++; 1755 } 1756 void exit_critical() { 1757 assert(Thread::current() == this, "this must be current thread"); 1758 _jni_active_critical--; 1759 assert(_jni_active_critical >= 0, "JNI critical nesting problem?"); 1760 } 1761 1762 // Checked JNI: is the programmer required to check for exceptions, if so specify 1763 // which function name. Returning to a Java frame should implicitly clear the 1764 // pending check, this is done for Native->Java transitions (i.e. user JNI code). 1765 // VM->Java transistions are not cleared, it is expected that JNI code enclosed 1766 // within ThreadToNativeFromVM makes proper exception checks (i.e. VM internal). 1767 bool is_pending_jni_exception_check() const { return _pending_jni_exception_check_fn != NULL; } 1768 void clear_pending_jni_exception_check() { _pending_jni_exception_check_fn = NULL; } 1769 const char* get_pending_jni_exception_check() const { return _pending_jni_exception_check_fn; } 1770 void set_pending_jni_exception_check(const char* fn_name) { _pending_jni_exception_check_fn = (char*) fn_name; } 1771 1772 // For deadlock detection 1773 int depth_first_number() { return _depth_first_number; } 1774 void set_depth_first_number(int dfn) { _depth_first_number = dfn; } 1775 1776 private: 1777 void set_monitor_chunks(MonitorChunk* monitor_chunks) { _monitor_chunks = monitor_chunks; } 1778 1779 public: 1780 MonitorChunk* monitor_chunks() const { return _monitor_chunks; } 1781 void add_monitor_chunk(MonitorChunk* chunk); 1782 void remove_monitor_chunk(MonitorChunk* chunk); 1783 bool in_deopt_handler() const { return _in_deopt_handler > 0; } 1784 void inc_in_deopt_handler() { _in_deopt_handler++; } 1785 void dec_in_deopt_handler() { 1786 assert(_in_deopt_handler > 0, "mismatched deopt nesting"); 1787 if (_in_deopt_handler > 0) { // robustness 1788 _in_deopt_handler--; 1789 } 1790 } 1791 1792 private: 1793 void set_entry_point(ThreadFunction entry_point) { _entry_point = entry_point; } 1794 1795 public: 1796 1797 // Frame iteration; calls the function f for all frames on the stack 1798 void frames_do(void f(frame*, const RegisterMap*)); 1799 1800 // Memory operations 1801 void oops_do(OopClosure* f, CodeBlobClosure* cf); 1802 1803 // Sweeper operations 1804 virtual void nmethods_do(CodeBlobClosure* cf); 1805 1806 // RedefineClasses Support 1807 void metadata_do(void f(Metadata*)); 1808 1809 // Misc. operations 1810 char* name() const { return (char*)get_thread_name(); } 1811 void print_on(outputStream* st, bool print_extended_info) const; 1812 void print_on(outputStream* st) const { print_on(st, false); } 1813 void print_value(); 1814 void print_thread_state_on(outputStream*) const PRODUCT_RETURN; 1815 void print_thread_state() const PRODUCT_RETURN; 1816 void print_on_error(outputStream* st, char* buf, int buflen) const; 1817 void print_name_on_error(outputStream* st, char* buf, int buflen) const; 1818 void verify(); 1819 const char* get_thread_name() const; 1820 private: 1821 // factor out low-level mechanics for use in both normal and error cases 1822 const char* get_thread_name_string(char* buf = NULL, int buflen = 0) const; 1823 public: 1824 const char* get_threadgroup_name() const; 1825 const char* get_parent_name() const; 1826 1827 // Accessing frames 1828 frame last_frame() { 1829 _anchor.make_walkable(this); 1830 return pd_last_frame(); 1831 } 1832 javaVFrame* last_java_vframe(RegisterMap* reg_map); 1833 1834 // Returns method at 'depth' java or native frames down the stack 1835 // Used for security checks 1836 Klass* security_get_caller_class(int depth); 1837 1838 // Print stack trace in external format 1839 void print_stack_on(outputStream* st); 1840 void print_stack() { print_stack_on(tty); } 1841 1842 // Print stack traces in various internal formats 1843 void trace_stack() PRODUCT_RETURN; 1844 void trace_stack_from(vframe* start_vf) PRODUCT_RETURN; 1845 void trace_frames() PRODUCT_RETURN; 1846 void trace_oops() PRODUCT_RETURN; 1847 1848 // Print an annotated view of the stack frames 1849 void print_frame_layout(int depth = 0, bool validate_only = false) NOT_DEBUG_RETURN; 1850 void validate_frame_layout() { 1851 print_frame_layout(0, true); 1852 } 1853 1854 // Returns the number of stack frames on the stack 1855 int depth() const; 1856 1857 // Function for testing deoptimization 1858 void deoptimize(); 1859 void make_zombies(); 1860 1861 void deoptimized_wrt_marked_nmethods(); 1862 1863 public: 1864 // Returns the running thread as a JavaThread 1865 static inline JavaThread* current(); 1866 1867 // Returns the active Java thread. Do not use this if you know you are calling 1868 // from a JavaThread, as it's slower than JavaThread::current. If called from 1869 // the VMThread, it also returns the JavaThread that instigated the VMThread's 1870 // operation. You may not want that either. 1871 static JavaThread* active(); 1872 1873 inline CompilerThread* as_CompilerThread(); 1874 1875 public: 1876 virtual void run(); 1877 void thread_main_inner(); 1878 1879 private: 1880 // PRIVILEGED STACK 1881 PrivilegedElement* _privileged_stack_top; 1882 GrowableArray<oop>* _array_for_gc; 1883 public: 1884 1885 // Returns the privileged_stack information. 1886 PrivilegedElement* privileged_stack_top() const { return _privileged_stack_top; } 1887 void set_privileged_stack_top(PrivilegedElement *e) { _privileged_stack_top = e; } 1888 void register_array_for_gc(GrowableArray<oop>* array) { _array_for_gc = array; } 1889 1890 public: 1891 // Thread local information maintained by JVMTI. 1892 void set_jvmti_thread_state(JvmtiThreadState *value) { _jvmti_thread_state = value; } 1893 // A JvmtiThreadState is lazily allocated. This jvmti_thread_state() 1894 // getter is used to get this JavaThread's JvmtiThreadState if it has 1895 // one which means NULL can be returned. JvmtiThreadState::state_for() 1896 // is used to get the specified JavaThread's JvmtiThreadState if it has 1897 // one or it allocates a new JvmtiThreadState for the JavaThread and 1898 // returns it. JvmtiThreadState::state_for() will return NULL only if 1899 // the specified JavaThread is exiting. 1900 JvmtiThreadState *jvmti_thread_state() const { return _jvmti_thread_state; } 1901 static ByteSize jvmti_thread_state_offset() { return byte_offset_of(JavaThread, _jvmti_thread_state); } 1902 1903 // JVMTI PopFrame support 1904 // Setting and clearing popframe_condition 1905 // All of these enumerated values are bits. popframe_pending 1906 // indicates that a PopFrame() has been requested and not yet been 1907 // completed. popframe_processing indicates that that PopFrame() is in 1908 // the process of being completed. popframe_force_deopt_reexecution_bit 1909 // indicates that special handling is required when returning to a 1910 // deoptimized caller. 1911 enum PopCondition { 1912 popframe_inactive = 0x00, 1913 popframe_pending_bit = 0x01, 1914 popframe_processing_bit = 0x02, 1915 popframe_force_deopt_reexecution_bit = 0x04 1916 }; 1917 PopCondition popframe_condition() { return (PopCondition) _popframe_condition; } 1918 void set_popframe_condition(PopCondition c) { _popframe_condition = c; } 1919 void set_popframe_condition_bit(PopCondition c) { _popframe_condition |= c; } 1920 void clear_popframe_condition() { _popframe_condition = popframe_inactive; } 1921 static ByteSize popframe_condition_offset() { return byte_offset_of(JavaThread, _popframe_condition); } 1922 bool has_pending_popframe() { return (popframe_condition() & popframe_pending_bit) != 0; } 1923 bool popframe_forcing_deopt_reexecution() { return (popframe_condition() & popframe_force_deopt_reexecution_bit) != 0; } 1924 void clear_popframe_forcing_deopt_reexecution() { _popframe_condition &= ~popframe_force_deopt_reexecution_bit; } 1925 #ifdef CC_INTERP 1926 bool pop_frame_pending(void) { return ((_popframe_condition & popframe_pending_bit) != 0); } 1927 void clr_pop_frame_pending(void) { _popframe_condition = popframe_inactive; } 1928 bool pop_frame_in_process(void) { return ((_popframe_condition & popframe_processing_bit) != 0); } 1929 void set_pop_frame_in_process(void) { _popframe_condition |= popframe_processing_bit; } 1930 void clr_pop_frame_in_process(void) { _popframe_condition &= ~popframe_processing_bit; } 1931 #endif 1932 1933 int frames_to_pop_failed_realloc() const { return _frames_to_pop_failed_realloc; } 1934 void set_frames_to_pop_failed_realloc(int nb) { _frames_to_pop_failed_realloc = nb; } 1935 void dec_frames_to_pop_failed_realloc() { _frames_to_pop_failed_realloc--; } 1936 1937 private: 1938 // Saved incoming arguments to popped frame. 1939 // Used only when popped interpreted frame returns to deoptimized frame. 1940 void* _popframe_preserved_args; 1941 int _popframe_preserved_args_size; 1942 1943 public: 1944 void popframe_preserve_args(ByteSize size_in_bytes, void* start); 1945 void* popframe_preserved_args(); 1946 ByteSize popframe_preserved_args_size(); 1947 WordSize popframe_preserved_args_size_in_words(); 1948 void popframe_free_preserved_args(); 1949 1950 1951 private: 1952 JvmtiThreadState *_jvmti_thread_state; 1953 1954 // Used by the interpreter in fullspeed mode for frame pop, method 1955 // entry, method exit and single stepping support. This field is 1956 // only set to non-zero by the VM_EnterInterpOnlyMode VM operation. 1957 // It can be set to zero asynchronously (i.e., without a VM operation 1958 // or a lock) so we have to be very careful. 1959 int _interp_only_mode; 1960 1961 public: 1962 // used by the interpreter for fullspeed debugging support (see above) 1963 static ByteSize interp_only_mode_offset() { return byte_offset_of(JavaThread, _interp_only_mode); } 1964 bool is_interp_only_mode() { return (_interp_only_mode != 0); } 1965 int get_interp_only_mode() { return _interp_only_mode; } 1966 void increment_interp_only_mode() { ++_interp_only_mode; } 1967 void decrement_interp_only_mode() { --_interp_only_mode; } 1968 1969 // support for cached flag that indicates whether exceptions need to be posted for this thread 1970 // if this is false, we can avoid deoptimizing when events are thrown 1971 // this gets set to reflect whether jvmtiExport::post_exception_throw would actually do anything 1972 private: 1973 int _should_post_on_exceptions_flag; 1974 1975 public: 1976 int should_post_on_exceptions_flag() { return _should_post_on_exceptions_flag; } 1977 void set_should_post_on_exceptions_flag(int val) { _should_post_on_exceptions_flag = val; } 1978 1979 private: 1980 ThreadStatistics *_thread_stat; 1981 1982 public: 1983 ThreadStatistics* get_thread_stat() const { return _thread_stat; } 1984 1985 // Return a blocker object for which this thread is blocked parking. 1986 oop current_park_blocker(); 1987 1988 private: 1989 static size_t _stack_size_at_create; 1990 1991 public: 1992 static inline size_t stack_size_at_create(void) { 1993 return _stack_size_at_create; 1994 } 1995 static inline void set_stack_size_at_create(size_t value) { 1996 _stack_size_at_create = value; 1997 } 1998 1999 // Machine dependent stuff 2000 #include OS_CPU_HEADER(thread) 2001 2002 public: 2003 void set_blocked_on_compilation(bool value) { 2004 _blocked_on_compilation = value; 2005 } 2006 2007 bool blocked_on_compilation() { 2008 return _blocked_on_compilation; 2009 } 2010 protected: 2011 bool _blocked_on_compilation; 2012 2013 2014 // JSR166 per-thread parker 2015 private: 2016 Parker* _parker; 2017 public: 2018 Parker* parker() { return _parker; } 2019 2020 // Biased locking support 2021 private: 2022 GrowableArray<MonitorInfo*>* _cached_monitor_info; 2023 public: 2024 GrowableArray<MonitorInfo*>* cached_monitor_info() { return _cached_monitor_info; } 2025 void set_cached_monitor_info(GrowableArray<MonitorInfo*>* info) { _cached_monitor_info = info; } 2026 2027 // clearing/querying jni attach status 2028 bool is_attaching_via_jni() const { return _jni_attach_state == _attaching_via_jni; } 2029 bool has_attached_via_jni() const { return is_attaching_via_jni() || _jni_attach_state == _attached_via_jni; } 2030 inline void set_done_attaching_via_jni(); 2031 }; 2032 2033 // Inline implementation of JavaThread::current 2034 inline JavaThread* JavaThread::current() { 2035 Thread* thread = Thread::current(); 2036 assert(thread->is_Java_thread(), "just checking"); 2037 return (JavaThread*)thread; 2038 } 2039 2040 inline CompilerThread* JavaThread::as_CompilerThread() { 2041 assert(is_Compiler_thread(), "just checking"); 2042 return (CompilerThread*)this; 2043 } 2044 2045 // Dedicated thread to sweep the code cache 2046 class CodeCacheSweeperThread : public JavaThread { 2047 CompiledMethod* _scanned_compiled_method; // nmethod being scanned by the sweeper 2048 public: 2049 CodeCacheSweeperThread(); 2050 // Track the nmethod currently being scanned by the sweeper 2051 void set_scanned_compiled_method(CompiledMethod* cm) { 2052 assert(_scanned_compiled_method == NULL || cm == NULL, "should reset to NULL before writing a new value"); 2053 _scanned_compiled_method = cm; 2054 } 2055 2056 // Hide sweeper thread from external view. 2057 bool is_hidden_from_external_view() const { return true; } 2058 2059 bool is_Code_cache_sweeper_thread() const { return true; } 2060 2061 // Prevent GC from unloading _scanned_compiled_method 2062 void oops_do(OopClosure* f, CodeBlobClosure* cf); 2063 void nmethods_do(CodeBlobClosure* cf); 2064 }; 2065 2066 // A thread used for Compilation. 2067 class CompilerThread : public JavaThread { 2068 friend class VMStructs; 2069 private: 2070 CompilerCounters* _counters; 2071 2072 ciEnv* _env; 2073 CompileLog* _log; 2074 CompileTask* volatile _task; // print_threads_compiling can read this concurrently. 2075 CompileQueue* _queue; 2076 BufferBlob* _buffer_blob; 2077 2078 AbstractCompiler* _compiler; 2079 TimeStamp _idle_time; 2080 2081 public: 2082 2083 static CompilerThread* current(); 2084 2085 CompilerThread(CompileQueue* queue, CompilerCounters* counters); 2086 ~CompilerThread(); 2087 2088 bool is_Compiler_thread() const { return true; } 2089 2090 virtual bool can_call_java() const; 2091 2092 // Hide native compiler threads from external view. 2093 bool is_hidden_from_external_view() const { return !can_call_java(); } 2094 2095 void set_compiler(AbstractCompiler* c) { _compiler = c; } 2096 AbstractCompiler* compiler() const { return _compiler; } 2097 2098 CompileQueue* queue() const { return _queue; } 2099 CompilerCounters* counters() const { return _counters; } 2100 2101 // Get/set the thread's compilation environment. 2102 ciEnv* env() { return _env; } 2103 void set_env(ciEnv* env) { _env = env; } 2104 2105 BufferBlob* get_buffer_blob() const { return _buffer_blob; } 2106 void set_buffer_blob(BufferBlob* b) { _buffer_blob = b; } 2107 2108 // Get/set the thread's logging information 2109 CompileLog* log() { return _log; } 2110 void init_log(CompileLog* log) { 2111 // Set once, for good. 2112 assert(_log == NULL, "set only once"); 2113 _log = log; 2114 } 2115 2116 void start_idle_timer() { _idle_time.update(); } 2117 jlong idle_time_millis() { 2118 return TimeHelper::counter_to_millis(_idle_time.ticks_since_update()); 2119 } 2120 2121 #ifndef PRODUCT 2122 private: 2123 IdealGraphPrinter *_ideal_graph_printer; 2124 public: 2125 IdealGraphPrinter *ideal_graph_printer() { return _ideal_graph_printer; } 2126 void set_ideal_graph_printer(IdealGraphPrinter *n) { _ideal_graph_printer = n; } 2127 #endif 2128 2129 // Get/set the thread's current task 2130 CompileTask* task() { return _task; } 2131 void set_task(CompileTask* task) { _task = task; } 2132 }; 2133 2134 inline CompilerThread* CompilerThread::current() { 2135 return JavaThread::current()->as_CompilerThread(); 2136 } 2137 2138 // The active thread queue. It also keeps track of the current used 2139 // thread priorities. 2140 class Threads: AllStatic { 2141 friend class VMStructs; 2142 private: 2143 static JavaThread* _thread_list; 2144 static int _number_of_threads; 2145 static int _number_of_non_daemon_threads; 2146 static int _return_code; 2147 static int _thread_claim_parity; 2148 #ifdef ASSERT 2149 static bool _vm_complete; 2150 static size_t _threads_before_barrier_set; 2151 #endif 2152 2153 static void initialize_java_lang_classes(JavaThread* main_thread, TRAPS); 2154 static void initialize_jsr292_core_classes(TRAPS); 2155 2156 public: 2157 // Thread management 2158 // force_daemon is a concession to JNI, where we may need to add a 2159 // thread to the thread list before allocating its thread object 2160 static void add(JavaThread* p, bool force_daemon = false); 2161 static void remove(JavaThread* p); 2162 static void non_java_threads_do(ThreadClosure* tc); 2163 static void java_threads_do(ThreadClosure* tc); 2164 static void java_threads_and_vm_thread_do(ThreadClosure* tc); 2165 static void threads_do(ThreadClosure* tc); 2166 static void possibly_parallel_threads_do(bool is_par, ThreadClosure* tc); 2167 2168 // Initializes the vm and creates the vm thread 2169 static jint create_vm(JavaVMInitArgs* args, bool* canTryAgain); 2170 static void convert_vm_init_libraries_to_agents(); 2171 static void create_vm_init_libraries(); 2172 static void create_vm_init_agents(); 2173 static void shutdown_vm_agents(); 2174 static bool destroy_vm(); 2175 // Supported VM versions via JNI 2176 // Includes JNI_VERSION_1_1 2177 static jboolean is_supported_jni_version_including_1_1(jint version); 2178 // Does not include JNI_VERSION_1_1 2179 static jboolean is_supported_jni_version(jint version); 2180 2181 // The "thread claim parity" provides a way for threads to be claimed 2182 // by parallel worker tasks. 2183 // 2184 // Each thread contains a a "parity" field. A task will claim the 2185 // thread only if its parity field is the same as the global parity, 2186 // which is updated by calling change_thread_claim_parity(). 2187 // 2188 // For this to work change_thread_claim_parity() needs to be called 2189 // exactly once in sequential code before starting parallel tasks 2190 // that should claim threads. 2191 // 2192 // New threads get their parity set to 0 and change_thread_claim_parity() 2193 // never set the global parity to 0. 2194 static int thread_claim_parity() { return _thread_claim_parity; } 2195 static void change_thread_claim_parity(); 2196 static void assert_all_threads_claimed() NOT_DEBUG_RETURN; 2197 2198 // Apply "f->do_oop" to all root oops in all threads. 2199 // This version may only be called by sequential code. 2200 static void oops_do(OopClosure* f, CodeBlobClosure* cf); 2201 // This version may be called by sequential or parallel code. 2202 static void possibly_parallel_oops_do(bool is_par, OopClosure* f, CodeBlobClosure* cf); 2203 2204 // Apply "f->do_oop" to roots in all threads that 2205 // are part of compiled frames 2206 static void compiled_frame_oops_do(OopClosure* f, CodeBlobClosure* cf); 2207 2208 static void convert_hcode_pointers(); 2209 static void restore_hcode_pointers(); 2210 2211 // Sweeper 2212 static void nmethods_do(CodeBlobClosure* cf); 2213 2214 // RedefineClasses support 2215 static void metadata_do(void f(Metadata*)); 2216 static void metadata_handles_do(void f(Metadata*)); 2217 2218 #ifdef ASSERT 2219 static bool is_vm_complete() { return _vm_complete; } 2220 2221 static size_t threads_before_barrier_set() { 2222 return _threads_before_barrier_set; 2223 } 2224 2225 static void inc_threads_before_barrier_set() { 2226 ++_threads_before_barrier_set; 2227 } 2228 #endif // ASSERT 2229 2230 // Verification 2231 static void verify(); 2232 static void print_on(outputStream* st, bool print_stacks, bool internal_format, bool print_concurrent_locks, bool print_extended_info); 2233 static void print(bool print_stacks, bool internal_format) { 2234 // this function is only used by debug.cpp 2235 print_on(tty, print_stacks, internal_format, false /* no concurrent lock printed */, false /* simple format */); 2236 } 2237 static void print_on_error(outputStream* st, Thread* current, char* buf, int buflen); 2238 static void print_on_error(Thread* this_thread, outputStream* st, Thread* current, char* buf, 2239 int buflen, bool* found_current); 2240 static void print_threads_compiling(outputStream* st, char* buf, int buflen); 2241 2242 // Get Java threads that are waiting to enter a monitor. 2243 static GrowableArray<JavaThread*>* get_pending_threads(ThreadsList * t_list, 2244 int count, address monitor); 2245 2246 // Get owning Java thread from the monitor's owner field. 2247 static JavaThread *owning_thread_from_monitor_owner(ThreadsList * t_list, 2248 address owner); 2249 2250 // Number of threads on the active threads list 2251 static int number_of_threads() { return _number_of_threads; } 2252 // Number of non-daemon threads on the active threads list 2253 static int number_of_non_daemon_threads() { return _number_of_non_daemon_threads; } 2254 2255 // Deoptimizes all frames tied to marked nmethods 2256 static void deoptimized_wrt_marked_nmethods(); 2257 }; 2258 2259 2260 // Thread iterator 2261 class ThreadClosure: public StackObj { 2262 public: 2263 virtual void do_thread(Thread* thread) = 0; 2264 }; 2265 2266 class SignalHandlerMark: public StackObj { 2267 private: 2268 Thread* _thread; 2269 public: 2270 SignalHandlerMark(Thread* t) { 2271 _thread = t; 2272 if (_thread) _thread->enter_signal_handler(); 2273 } 2274 ~SignalHandlerMark() { 2275 if (_thread) _thread->leave_signal_handler(); 2276 _thread = NULL; 2277 } 2278 }; 2279 2280 2281 #endif // SHARE_VM_RUNTIME_THREAD_HPP