1 /* 2 * Copyright (c) 1997, 2017, 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 "gc/shared/threadLocalAllocBuffer.hpp" 29 #include "memory/allocation.hpp" 30 #include "oops/oop.hpp" 31 #include "prims/jni.h" 32 #include "prims/jvmtiExport.hpp" 33 #include "runtime/frame.hpp" 34 #include "runtime/javaFrameAnchor.hpp" 35 #include "runtime/jniHandles.hpp" 36 #include "runtime/mutexLocker.hpp" 37 #include "runtime/os.hpp" 38 #include "runtime/osThread.hpp" 39 #include "runtime/park.hpp" 40 #include "runtime/safepoint.hpp" 41 #include "runtime/stubRoutines.hpp" 42 #include "runtime/threadLocalStorage.hpp" 43 #include "runtime/thread_ext.hpp" 44 #include "runtime/unhandledOops.hpp" 45 #include "trace/traceBackend.hpp" 46 #include "trace/traceMacros.hpp" 47 #include "utilities/exceptions.hpp" 48 #include "utilities/macros.hpp" 49 #if INCLUDE_ALL_GCS 50 #include "gc/g1/dirtyCardQueue.hpp" 51 #include "gc/g1/satbMarkQueue.hpp" 52 #endif // INCLUDE_ALL_GCS 53 #ifdef ZERO 54 # include "stack_zero.hpp" 55 #endif 56 57 class ThreadSafepointState; 58 class ThreadProfiler; 59 60 class JvmtiThreadState; 61 class JvmtiGetLoadedClassesClosure; 62 class ThreadStatistics; 63 class ConcurrentLocksDump; 64 class ParkEvent; 65 class Parker; 66 67 class ciEnv; 68 class CompileThread; 69 class CompileLog; 70 class CompileTask; 71 class CompileQueue; 72 class CompilerCounters; 73 class vframeArray; 74 75 class DeoptResourceMark; 76 class jvmtiDeferredLocalVariableSet; 77 78 class GCTaskQueue; 79 class ThreadClosure; 80 class IdealGraphPrinter; 81 82 class Metadata; 83 template <class T, MEMFLAGS F> class ChunkedList; 84 typedef ChunkedList<Metadata*, mtInternal> MetadataOnStackBuffer; 85 86 DEBUG_ONLY(class ResourceMark;) 87 88 class WorkerThread; 89 90 // Class hierarchy 91 // - Thread 92 // - NamedThread 93 // - VMThread 94 // - ConcurrentGCThread 95 // - WorkerThread 96 // - GangWorker 97 // - GCTaskThread 98 // - JavaThread 99 // - various subclasses eg CompilerThread, ServiceThread 100 // - WatcherThread 101 102 class Thread: public ThreadShadow { 103 friend class VMStructs; 104 friend class JVMCIVMStructs; 105 private: 106 107 #ifndef USE_LIBRARY_BASED_TLS_ONLY 108 // Current thread is maintained as a thread-local variable 109 static THREAD_LOCAL_DECL Thread* _thr_current; 110 #endif 111 112 // Exception handling 113 // (Note: _pending_exception and friends are in ThreadShadow) 114 //oop _pending_exception; // pending exception for current thread 115 // const char* _exception_file; // file information for exception (debugging only) 116 // int _exception_line; // line information for exception (debugging only) 117 protected: 118 // Support for forcing alignment of thread objects for biased locking 119 void* _real_malloc_address; 120 public: 121 void* operator new(size_t size) throw() { return allocate(size, true); } 122 void* operator new(size_t size, const std::nothrow_t& nothrow_constant) throw() { 123 return allocate(size, false); } 124 void operator delete(void* p); 125 126 protected: 127 static void* allocate(size_t size, bool throw_excpt, MEMFLAGS flags = mtThread); 128 private: 129 130 // *************************************************************** 131 // Suspend and resume support 132 // *************************************************************** 133 // 134 // VM suspend/resume no longer exists - it was once used for various 135 // things including safepoints but was deprecated and finally removed 136 // in Java 7. Because VM suspension was considered "internal" Java-level 137 // suspension was considered "external", and this legacy naming scheme 138 // remains. 139 // 140 // External suspend/resume requests come from JVM_SuspendThread, 141 // JVM_ResumeThread, JVMTI SuspendThread, and finally JVMTI 142 // ResumeThread. External 143 // suspend requests cause _external_suspend to be set and external 144 // resume requests cause _external_suspend to be cleared. 145 // External suspend requests do not nest on top of other external 146 // suspend requests. The higher level APIs reject suspend requests 147 // for already suspended threads. 148 // 149 // The external_suspend 150 // flag is checked by has_special_runtime_exit_condition() and java thread 151 // will self-suspend when handle_special_runtime_exit_condition() is 152 // called. Most uses of the _thread_blocked state in JavaThreads are 153 // considered the same as being externally suspended; if the blocking 154 // condition lifts, the JavaThread will self-suspend. Other places 155 // where VM checks for external_suspend include: 156 // + mutex granting (do not enter monitors when thread is suspended) 157 // + state transitions from _thread_in_native 158 // 159 // In general, java_suspend() does not wait for an external suspend 160 // request to complete. When it returns, the only guarantee is that 161 // the _external_suspend field is true. 162 // 163 // wait_for_ext_suspend_completion() is used to wait for an external 164 // suspend request to complete. External suspend requests are usually 165 // followed by some other interface call that requires the thread to 166 // be quiescent, e.g., GetCallTrace(). By moving the "wait time" into 167 // the interface that requires quiescence, we give the JavaThread a 168 // chance to self-suspend before we need it to be quiescent. This 169 // improves overall suspend/query performance. 170 // 171 // _suspend_flags controls the behavior of java_ suspend/resume. 172 // It must be set under the protection of SR_lock. Read from the flag is 173 // OK without SR_lock as long as the value is only used as a hint. 174 // (e.g., check _external_suspend first without lock and then recheck 175 // inside SR_lock and finish the suspension) 176 // 177 // _suspend_flags is also overloaded for other "special conditions" so 178 // that a single check indicates whether any special action is needed 179 // eg. for async exceptions. 180 // ------------------------------------------------------------------- 181 // Notes: 182 // 1. The suspend/resume logic no longer uses ThreadState in OSThread 183 // but we still update its value to keep other part of the system (mainly 184 // JVMTI) happy. ThreadState is legacy code (see notes in 185 // osThread.hpp). 186 // 187 // 2. It would be more natural if set_external_suspend() is private and 188 // part of java_suspend(), but that probably would affect the suspend/query 189 // performance. Need more investigation on this. 190 191 // suspend/resume lock: used for self-suspend 192 Monitor* _SR_lock; 193 194 protected: 195 enum SuspendFlags { 196 // NOTE: avoid using the sign-bit as cc generates different test code 197 // when the sign-bit is used, and sometimes incorrectly - see CR 6398077 198 199 _external_suspend = 0x20000000U, // thread is asked to self suspend 200 _ext_suspended = 0x40000000U, // thread has self-suspended 201 _deopt_suspend = 0x10000000U, // thread needs to self suspend for deopt 202 203 _has_async_exception = 0x00000001U, // there is a pending async exception 204 _critical_native_unlock = 0x00000002U, // Must call back to unlock JNI critical lock 205 206 _trace_flag = 0x00000004U // call tracing backend 207 }; 208 209 // various suspension related flags - atomically updated 210 // overloaded for async exception checking in check_special_condition_for_native_trans. 211 volatile uint32_t _suspend_flags; 212 213 private: 214 int _num_nested_signal; 215 216 DEBUG_ONLY(bool _suspendible_thread;) 217 218 public: 219 void enter_signal_handler() { _num_nested_signal++; } 220 void leave_signal_handler() { _num_nested_signal--; } 221 bool is_inside_signal_handler() const { return _num_nested_signal > 0; } 222 223 #ifdef ASSERT 224 void set_suspendible_thread() { 225 _suspendible_thread = true; 226 } 227 228 void clear_suspendible_thread() { 229 _suspendible_thread = false; 230 } 231 232 bool is_suspendible_thread() { return _suspendible_thread; } 233 #endif 234 235 private: 236 // Active_handles points to a block of handles 237 JNIHandleBlock* _active_handles; 238 239 // One-element thread local free list 240 JNIHandleBlock* _free_handle_block; 241 242 // Point to the last handle mark 243 HandleMark* _last_handle_mark; 244 245 // The parity of the last strong_roots iteration in which this thread was 246 // claimed as a task. 247 jint _oops_do_parity; 248 249 public: 250 void set_last_handle_mark(HandleMark* mark) { _last_handle_mark = mark; } 251 HandleMark* last_handle_mark() const { return _last_handle_mark; } 252 private: 253 254 // debug support for checking if code does allow safepoints or not 255 // GC points in the VM can happen because of allocation, invoking a VM operation, or blocking on 256 // mutex, or blocking on an object synchronizer (Java locking). 257 // If !allow_safepoint(), then an assertion failure will happen in any of the above cases 258 // If !allow_allocation(), then an assertion failure will happen during allocation 259 // (Hence, !allow_safepoint() => !allow_allocation()). 260 // 261 // The two classes NoSafepointVerifier and No_Allocation_Verifier are used to set these counters. 262 // 263 NOT_PRODUCT(int _allow_safepoint_count;) // If 0, thread allow a safepoint to happen 264 debug_only(int _allow_allocation_count;) // If 0, the thread is allowed to allocate oops. 265 266 // Used by SkipGCALot class. 267 NOT_PRODUCT(bool _skip_gcalot;) // Should we elide gc-a-lot? 268 269 friend class NoAllocVerifier; 270 friend class NoSafepointVerifier; 271 friend class PauseNoSafepointVerifier; 272 friend class GCLocker; 273 274 ThreadLocalAllocBuffer _tlab; // Thread-local eden 275 jlong _allocated_bytes; // Cumulative number of bytes allocated on 276 // the Java heap 277 278 mutable TRACE_DATA _trace_data; // Thread-local data for tracing 279 280 ThreadExt _ext; 281 282 int _vm_operation_started_count; // VM_Operation support 283 int _vm_operation_completed_count; // VM_Operation support 284 285 ObjectMonitor* _current_pending_monitor; // ObjectMonitor this thread 286 // is waiting to lock 287 bool _current_pending_monitor_is_from_java; // locking is from Java code 288 289 // ObjectMonitor on which this thread called Object.wait() 290 ObjectMonitor* _current_waiting_monitor; 291 292 // Private thread-local objectmonitor list - a simple cache organized as a SLL. 293 public: 294 ObjectMonitor* omFreeList; 295 int omFreeCount; // length of omFreeList 296 int omFreeProvision; // reload chunk size 297 ObjectMonitor* omInUseList; // SLL to track monitors in circulation 298 int omInUseCount; // length of omInUseList 299 300 #ifdef ASSERT 301 private: 302 bool _visited_for_critical_count; 303 304 public: 305 void set_visited_for_critical_count(bool z) { _visited_for_critical_count = z; } 306 bool was_visited_for_critical_count() const { return _visited_for_critical_count; } 307 #endif 308 309 public: 310 enum { 311 is_definitely_current_thread = true 312 }; 313 314 // Constructor 315 Thread(); 316 virtual ~Thread(); 317 318 // Manage Thread::current() 319 void initialize_thread_current(); 320 void clear_thread_current(); // TLS cleanup needed before threads terminate 321 322 public: 323 // thread entry point 324 virtual void run(); 325 326 // Testers 327 virtual bool is_VM_thread() const { return false; } 328 virtual bool is_Java_thread() const { return false; } 329 virtual bool is_Compiler_thread() const { return false; } 330 virtual bool is_Code_cache_sweeper_thread() const { return false; } 331 virtual bool is_hidden_from_external_view() const { return false; } 332 virtual bool is_jvmti_agent_thread() const { return false; } 333 // True iff the thread can perform GC operations at a safepoint. 334 // Generally will be true only of VM thread and parallel GC WorkGang 335 // threads. 336 virtual bool is_GC_task_thread() const { return false; } 337 virtual bool is_Watcher_thread() const { return false; } 338 virtual bool is_ConcurrentGC_thread() const { return false; } 339 virtual bool is_Named_thread() const { return false; } 340 virtual bool is_Worker_thread() const { return false; } 341 342 // Can this thread make Java upcalls 343 virtual bool can_call_java() const { return false; } 344 345 // Casts 346 virtual WorkerThread* as_Worker_thread() const { return NULL; } 347 348 virtual char* name() const { return (char*)"Unknown thread"; } 349 350 // Returns the current thread (ASSERTS if NULL) 351 static inline Thread* current(); 352 // Returns the current thread, or NULL if not attached 353 static inline Thread* current_or_null(); 354 // Returns the current thread, or NULL if not attached, and is 355 // safe for use from signal-handlers 356 static inline Thread* current_or_null_safe(); 357 358 // Common thread operations 359 static void set_priority(Thread* thread, ThreadPriority priority); 360 static ThreadPriority get_priority(const Thread* const thread); 361 static void start(Thread* thread); 362 static void interrupt(Thread* thr); 363 static bool is_interrupted(Thread* thr, bool clear_interrupted); 364 365 void set_native_thread_name(const char *name) { 366 assert(Thread::current() == this, "set_native_thread_name can only be called on the current thread"); 367 os::set_native_thread_name(name); 368 } 369 370 ObjectMonitor** omInUseList_addr() { return (ObjectMonitor **)&omInUseList; } 371 Monitor* SR_lock() const { return _SR_lock; } 372 373 bool has_async_exception() const { return (_suspend_flags & _has_async_exception) != 0; } 374 375 inline void set_suspend_flag(SuspendFlags f); 376 inline void clear_suspend_flag(SuspendFlags f); 377 378 inline void set_has_async_exception(); 379 inline void clear_has_async_exception(); 380 381 bool do_critical_native_unlock() const { return (_suspend_flags & _critical_native_unlock) != 0; } 382 383 inline void set_critical_native_unlock(); 384 inline void clear_critical_native_unlock(); 385 386 inline void set_trace_flag(); 387 inline void clear_trace_flag(); 388 389 // Support for Unhandled Oop detection 390 // Add the field for both, fastdebug and debug, builds to keep 391 // Thread's fields layout the same. 392 // Note: CHECK_UNHANDLED_OOPS is defined only for fastdebug build. 393 #ifdef CHECK_UNHANDLED_OOPS 394 private: 395 UnhandledOops* _unhandled_oops; 396 #elif defined(ASSERT) 397 private: 398 void* _unhandled_oops; 399 #endif 400 #ifdef CHECK_UNHANDLED_OOPS 401 public: 402 UnhandledOops* unhandled_oops() { return _unhandled_oops; } 403 // Mark oop safe for gc. It may be stack allocated but won't move. 404 void allow_unhandled_oop(oop *op) { 405 if (CheckUnhandledOops) unhandled_oops()->allow_unhandled_oop(op); 406 } 407 // Clear oops at safepoint so crashes point to unhandled oop violator 408 void clear_unhandled_oops() { 409 if (CheckUnhandledOops) unhandled_oops()->clear_unhandled_oops(); 410 } 411 #endif // CHECK_UNHANDLED_OOPS 412 413 public: 414 #ifndef PRODUCT 415 bool skip_gcalot() { return _skip_gcalot; } 416 void set_skip_gcalot(bool v) { _skip_gcalot = v; } 417 #endif 418 419 // Installs a pending exception to be inserted later 420 static void send_async_exception(oop thread_oop, oop java_throwable); 421 422 // Resource area 423 ResourceArea* resource_area() const { return _resource_area; } 424 void set_resource_area(ResourceArea* area) { _resource_area = area; } 425 426 OSThread* osthread() const { return _osthread; } 427 void set_osthread(OSThread* thread) { _osthread = thread; } 428 429 // JNI handle support 430 JNIHandleBlock* active_handles() const { return _active_handles; } 431 void set_active_handles(JNIHandleBlock* block) { _active_handles = block; } 432 JNIHandleBlock* free_handle_block() const { return _free_handle_block; } 433 void set_free_handle_block(JNIHandleBlock* block) { _free_handle_block = block; } 434 435 // Internal handle support 436 HandleArea* handle_area() const { return _handle_area; } 437 void set_handle_area(HandleArea* area) { _handle_area = area; } 438 439 GrowableArray<Metadata*>* metadata_handles() const { return _metadata_handles; } 440 void set_metadata_handles(GrowableArray<Metadata*>* handles){ _metadata_handles = handles; } 441 442 // Thread-Local Allocation Buffer (TLAB) support 443 ThreadLocalAllocBuffer& tlab() { return _tlab; } 444 void initialize_tlab() { 445 if (UseTLAB) { 446 tlab().initialize(); 447 } 448 } 449 450 jlong allocated_bytes() { return _allocated_bytes; } 451 void set_allocated_bytes(jlong value) { _allocated_bytes = value; } 452 void incr_allocated_bytes(jlong size) { _allocated_bytes += size; } 453 inline jlong cooked_allocated_bytes(); 454 455 TRACE_DEFINE_THREAD_TRACE_DATA_OFFSET; 456 TRACE_DATA* trace_data() const { return &_trace_data; } 457 bool is_trace_suspend() { return (_suspend_flags & _trace_flag) != 0; } 458 459 const ThreadExt& ext() const { return _ext; } 460 ThreadExt& ext() { return _ext; } 461 462 // VM operation support 463 int vm_operation_ticket() { return ++_vm_operation_started_count; } 464 int vm_operation_completed_count() { return _vm_operation_completed_count; } 465 void increment_vm_operation_completed_count() { _vm_operation_completed_count++; } 466 467 // For tracking the heavyweight monitor the thread is pending on. 468 ObjectMonitor* current_pending_monitor() { 469 return _current_pending_monitor; 470 } 471 void set_current_pending_monitor(ObjectMonitor* monitor) { 472 _current_pending_monitor = monitor; 473 } 474 void set_current_pending_monitor_is_from_java(bool from_java) { 475 _current_pending_monitor_is_from_java = from_java; 476 } 477 bool current_pending_monitor_is_from_java() { 478 return _current_pending_monitor_is_from_java; 479 } 480 481 // For tracking the ObjectMonitor on which this thread called Object.wait() 482 ObjectMonitor* current_waiting_monitor() { 483 return _current_waiting_monitor; 484 } 485 void set_current_waiting_monitor(ObjectMonitor* monitor) { 486 _current_waiting_monitor = monitor; 487 } 488 489 // GC support 490 // Apply "f->do_oop" to all root oops in "this". 491 // Used by JavaThread::oops_do. 492 // Apply "cf->do_code_blob" (if !NULL) to all code blobs active in frames 493 virtual void oops_do(OopClosure* f, CodeBlobClosure* cf); 494 495 // Handles the parallel case for the method below. 496 private: 497 bool claim_oops_do_par_case(int collection_parity); 498 public: 499 // Requires that "collection_parity" is that of the current roots 500 // iteration. If "is_par" is false, sets the parity of "this" to 501 // "collection_parity", and returns "true". If "is_par" is true, 502 // uses an atomic instruction to set the current threads parity to 503 // "collection_parity", if it is not already. Returns "true" iff the 504 // calling thread does the update, this indicates that the calling thread 505 // has claimed the thread's stack as a root groop in the current 506 // collection. 507 bool claim_oops_do(bool is_par, int collection_parity) { 508 if (!is_par) { 509 _oops_do_parity = collection_parity; 510 return true; 511 } else { 512 return claim_oops_do_par_case(collection_parity); 513 } 514 } 515 516 // jvmtiRedefineClasses support 517 void metadata_handles_do(void f(Metadata*)); 518 519 // Used by fast lock support 520 virtual bool is_lock_owned(address adr) const; 521 522 // Check if address is in the stack of the thread (not just for locks). 523 // Warning: the method can only be used on the running thread 524 bool is_in_stack(address adr) const; 525 // Check if address is in the usable part of the stack (excludes protected 526 // guard pages) 527 bool is_in_usable_stack(address adr) const; 528 529 // Sets this thread as starting thread. Returns failure if thread 530 // creation fails due to lack of memory, too many threads etc. 531 bool set_as_starting_thread(); 532 533 protected: 534 // OS data associated with the thread 535 OSThread* _osthread; // Platform-specific thread information 536 537 // Thread local resource area for temporary allocation within the VM 538 ResourceArea* _resource_area; 539 540 DEBUG_ONLY(ResourceMark* _current_resource_mark;) 541 542 // Thread local handle area for allocation of handles within the VM 543 HandleArea* _handle_area; 544 GrowableArray<Metadata*>* _metadata_handles; 545 546 // Support for stack overflow handling, get_thread, etc. 547 address _stack_base; 548 size_t _stack_size; 549 uintptr_t _self_raw_id; // used by get_thread (mutable) 550 int _lgrp_id; 551 552 public: 553 // Stack overflow support 554 address stack_base() const { assert(_stack_base != NULL,"Sanity check"); return _stack_base; } 555 void set_stack_base(address base) { _stack_base = base; } 556 size_t stack_size() const { return _stack_size; } 557 void set_stack_size(size_t size) { _stack_size = size; } 558 address stack_end() const { return stack_base() - stack_size(); } 559 void record_stack_base_and_size(); 560 561 bool on_local_stack(address adr) const { 562 // QQQ this has knowledge of direction, ought to be a stack method 563 return (_stack_base >= adr && adr >= stack_end()); 564 } 565 566 uintptr_t self_raw_id() { return _self_raw_id; } 567 void set_self_raw_id(uintptr_t value) { _self_raw_id = value; } 568 569 int lgrp_id() const { return _lgrp_id; } 570 void set_lgrp_id(int value) { _lgrp_id = value; } 571 572 // Printing 573 virtual void print_on(outputStream* st) const; 574 void print() const { print_on(tty); } 575 virtual void print_on_error(outputStream* st, char* buf, int buflen) const; 576 577 // Debug-only code 578 #ifdef ASSERT 579 private: 580 // Deadlock detection support for Mutex locks. List of locks own by thread. 581 Monitor* _owned_locks; 582 // Mutex::set_owner_implementation is the only place where _owned_locks is modified, 583 // thus the friendship 584 friend class Mutex; 585 friend class Monitor; 586 587 public: 588 void print_owned_locks_on(outputStream* st) const; 589 void print_owned_locks() const { print_owned_locks_on(tty); } 590 Monitor* owned_locks() const { return _owned_locks; } 591 bool owns_locks() const { return owned_locks() != NULL; } 592 bool owns_locks_but_compiled_lock() const; 593 int oops_do_parity() const { return _oops_do_parity; } 594 595 // Deadlock detection 596 bool allow_allocation() { return _allow_allocation_count == 0; } 597 ResourceMark* current_resource_mark() { return _current_resource_mark; } 598 void set_current_resource_mark(ResourceMark* rm) { _current_resource_mark = rm; } 599 #endif 600 601 void check_for_valid_safepoint_state(bool potential_vm_operation) PRODUCT_RETURN; 602 603 private: 604 volatile int _jvmti_env_iteration_count; 605 606 public: 607 void entering_jvmti_env_iteration() { ++_jvmti_env_iteration_count; } 608 void leaving_jvmti_env_iteration() { --_jvmti_env_iteration_count; } 609 bool is_inside_jvmti_env_iteration() { return _jvmti_env_iteration_count > 0; } 610 611 // Code generation 612 static ByteSize exception_file_offset() { return byte_offset_of(Thread, _exception_file); } 613 static ByteSize exception_line_offset() { return byte_offset_of(Thread, _exception_line); } 614 static ByteSize active_handles_offset() { return byte_offset_of(Thread, _active_handles); } 615 616 static ByteSize stack_base_offset() { return byte_offset_of(Thread, _stack_base); } 617 static ByteSize stack_size_offset() { return byte_offset_of(Thread, _stack_size); } 618 619 #define TLAB_FIELD_OFFSET(name) \ 620 static ByteSize tlab_##name##_offset() { return byte_offset_of(Thread, _tlab) + ThreadLocalAllocBuffer::name##_offset(); } 621 622 TLAB_FIELD_OFFSET(start) 623 TLAB_FIELD_OFFSET(end) 624 TLAB_FIELD_OFFSET(top) 625 TLAB_FIELD_OFFSET(pf_top) 626 TLAB_FIELD_OFFSET(size) // desired_size 627 TLAB_FIELD_OFFSET(refill_waste_limit) 628 TLAB_FIELD_OFFSET(number_of_refills) 629 TLAB_FIELD_OFFSET(fast_refill_waste) 630 TLAB_FIELD_OFFSET(slow_allocations) 631 632 #undef TLAB_FIELD_OFFSET 633 634 static ByteSize allocated_bytes_offset() { return byte_offset_of(Thread, _allocated_bytes); } 635 636 public: 637 volatile intptr_t _Stalled; 638 volatile int _TypeTag; 639 ParkEvent * _ParkEvent; // for synchronized() 640 ParkEvent * _SleepEvent; // for Thread.sleep 641 ParkEvent * _MutexEvent; // for native internal Mutex/Monitor 642 ParkEvent * _MuxEvent; // for low-level muxAcquire-muxRelease 643 int NativeSyncRecursion; // diagnostic 644 645 volatile int _OnTrap; // Resume-at IP delta 646 jint _hashStateW; // Marsaglia Shift-XOR thread-local RNG 647 jint _hashStateX; // thread-specific hashCode generator state 648 jint _hashStateY; 649 jint _hashStateZ; 650 void * _schedctl; 651 652 653 volatile jint rng[4]; // RNG for spin loop 654 655 // Low-level leaf-lock primitives used to implement synchronization 656 // and native monitor-mutex infrastructure. 657 // Not for general synchronization use. 658 static void SpinAcquire(volatile int * Lock, const char * Name); 659 static void SpinRelease(volatile int * Lock); 660 static void muxAcquire(volatile intptr_t * Lock, const char * Name); 661 static void muxAcquireW(volatile intptr_t * Lock, ParkEvent * ev); 662 static void muxRelease(volatile intptr_t * Lock); 663 }; 664 665 // Inline implementation of Thread::current() 666 inline Thread* Thread::current() { 667 Thread* current = current_or_null(); 668 assert(current != NULL, "Thread::current() called on detached thread"); 669 return current; 670 } 671 672 inline Thread* Thread::current_or_null() { 673 #ifndef USE_LIBRARY_BASED_TLS_ONLY 674 return _thr_current; 675 #else 676 return ThreadLocalStorage::thread(); 677 #endif 678 } 679 680 inline Thread* Thread::current_or_null_safe() { 681 return ThreadLocalStorage::thread(); 682 } 683 684 // Name support for threads. non-JavaThread subclasses with multiple 685 // uniquely named instances should derive from this. 686 class NamedThread: public Thread { 687 friend class VMStructs; 688 enum { 689 max_name_len = 64 690 }; 691 private: 692 char* _name; 693 // log JavaThread being processed by oops_do 694 JavaThread* _processed_thread; 695 uint _gc_id; // The current GC id when a thread takes part in GC 696 697 public: 698 NamedThread(); 699 ~NamedThread(); 700 // May only be called once per thread. 701 void set_name(const char* format, ...) ATTRIBUTE_PRINTF(2, 3); 702 void initialize_named_thread(); 703 virtual bool is_Named_thread() const { return true; } 704 virtual char* name() const { return _name == NULL ? (char*)"Unknown Thread" : _name; } 705 JavaThread *processed_thread() { return _processed_thread; } 706 void set_processed_thread(JavaThread *thread) { _processed_thread = thread; } 707 virtual void print_on(outputStream* st) const; 708 709 void set_gc_id(uint gc_id) { _gc_id = gc_id; } 710 uint gc_id() { return _gc_id; } 711 }; 712 713 // Worker threads are named and have an id of an assigned work. 714 class WorkerThread: public NamedThread { 715 private: 716 uint _id; 717 public: 718 WorkerThread() : _id(0) { } 719 virtual bool is_Worker_thread() const { return true; } 720 721 virtual WorkerThread* as_Worker_thread() const { 722 assert(is_Worker_thread(), "Dubious cast to WorkerThread*?"); 723 return (WorkerThread*) this; 724 } 725 726 void set_id(uint work_id) { _id = work_id; } 727 uint id() const { return _id; } 728 }; 729 730 // A single WatcherThread is used for simulating timer interrupts. 731 class WatcherThread: public Thread { 732 friend class VMStructs; 733 public: 734 virtual void run(); 735 736 private: 737 static WatcherThread* _watcher_thread; 738 739 static bool _startable; 740 // volatile due to at least one lock-free read 741 volatile static bool _should_terminate; 742 public: 743 enum SomeConstants { 744 delay_interval = 10 // interrupt delay in milliseconds 745 }; 746 747 // Constructor 748 WatcherThread(); 749 750 // No destruction allowed 751 ~WatcherThread() { 752 guarantee(false, "WatcherThread deletion must fix the race with VM termination"); 753 } 754 755 // Tester 756 bool is_Watcher_thread() const { return true; } 757 758 // Printing 759 char* name() const { return (char*)"VM Periodic Task Thread"; } 760 void print_on(outputStream* st) const; 761 void unpark(); 762 763 // Returns the single instance of WatcherThread 764 static WatcherThread* watcher_thread() { return _watcher_thread; } 765 766 // Create and start the single instance of WatcherThread, or stop it on shutdown 767 static void start(); 768 static void stop(); 769 // Only allow start once the VM is sufficiently initialized 770 // Otherwise the first task to enroll will trigger the start 771 static void make_startable(); 772 private: 773 int sleep() const; 774 }; 775 776 777 class CompilerThread; 778 779 typedef void (*ThreadFunction)(JavaThread*, TRAPS); 780 781 class JavaThread: public Thread { 782 friend class VMStructs; 783 friend class JVMCIVMStructs; 784 friend class WhiteBox; 785 private: 786 JavaThread* _next; // The next thread in the Threads list 787 oop _threadObj; // The Java level thread object 788 789 #ifdef ASSERT 790 private: 791 int _java_call_counter; 792 793 public: 794 int java_call_counter() { return _java_call_counter; } 795 void inc_java_call_counter() { _java_call_counter++; } 796 void dec_java_call_counter() { 797 assert(_java_call_counter > 0, "Invalid nesting of JavaCallWrapper"); 798 _java_call_counter--; 799 } 800 private: // restore original namespace restriction 801 #endif // ifdef ASSERT 802 803 #ifndef PRODUCT 804 public: 805 enum { 806 jump_ring_buffer_size = 16 807 }; 808 private: // restore original namespace restriction 809 #endif 810 811 JavaFrameAnchor _anchor; // Encapsulation of current java frame and it state 812 813 ThreadFunction _entry_point; 814 815 JNIEnv _jni_environment; 816 817 // Deopt support 818 DeoptResourceMark* _deopt_mark; // Holds special ResourceMark for deoptimization 819 820 intptr_t* _must_deopt_id; // id of frame that needs to be deopted once we 821 // transition out of native 822 CompiledMethod* _deopt_nmethod; // CompiledMethod that is currently being deoptimized 823 vframeArray* _vframe_array_head; // Holds the heap of the active vframeArrays 824 vframeArray* _vframe_array_last; // Holds last vFrameArray we popped 825 // Because deoptimization is lazy we must save jvmti requests to set locals 826 // in compiled frames until we deoptimize and we have an interpreter frame. 827 // This holds the pointer to array (yeah like there might be more than one) of 828 // description of compiled vframes that have locals that need to be updated. 829 GrowableArray<jvmtiDeferredLocalVariableSet*>* _deferred_locals_updates; 830 831 // Handshake value for fixing 6243940. We need a place for the i2c 832 // adapter to store the callee Method*. This value is NEVER live 833 // across a gc point so it does NOT have to be gc'd 834 // The handshake is open ended since we can't be certain that it will 835 // be NULLed. This is because we rarely ever see the race and end up 836 // in handle_wrong_method which is the backend of the handshake. See 837 // code in i2c adapters and handle_wrong_method. 838 839 Method* _callee_target; 840 841 // Used to pass back results to the interpreter or generated code running Java code. 842 oop _vm_result; // oop result is GC-preserved 843 Metadata* _vm_result_2; // non-oop result 844 845 // See ReduceInitialCardMarks: this holds the precise space interval of 846 // the most recent slow path allocation for which compiled code has 847 // elided card-marks for performance along the fast-path. 848 MemRegion _deferred_card_mark; 849 850 MonitorChunk* _monitor_chunks; // Contains the off stack monitors 851 // allocated during deoptimization 852 // and by JNI_MonitorEnter/Exit 853 854 // Async. requests support 855 enum AsyncRequests { 856 _no_async_condition = 0, 857 _async_exception, 858 _async_unsafe_access_error 859 }; 860 AsyncRequests _special_runtime_exit_condition; // Enum indicating pending async. request 861 oop _pending_async_exception; 862 863 // Safepoint support 864 public: // Expose _thread_state for SafeFetchInt() 865 volatile JavaThreadState _thread_state; 866 private: 867 ThreadSafepointState *_safepoint_state; // Holds information about a thread during a safepoint 868 address _saved_exception_pc; // Saved pc of instruction where last implicit exception happened 869 870 // JavaThread termination support 871 enum TerminatedTypes { 872 _not_terminated = 0xDEAD - 2, 873 _thread_exiting, // JavaThread::exit() has been called for this thread 874 _thread_terminated, // JavaThread is removed from thread list 875 _vm_exited // JavaThread is still executing native code, but VM is terminated 876 // only VM_Exit can set _vm_exited 877 }; 878 879 // In general a JavaThread's _terminated field transitions as follows: 880 // 881 // _not_terminated => _thread_exiting => _thread_terminated 882 // 883 // _vm_exited is a special value to cover the case of a JavaThread 884 // executing native code after the VM itself is terminated. 885 volatile TerminatedTypes _terminated; 886 // suspend/resume support 887 volatile bool _suspend_equivalent; // Suspend equivalent condition 888 jint _in_deopt_handler; // count of deoptimization 889 // handlers thread is in 890 volatile bool _doing_unsafe_access; // Thread may fault due to unsafe access 891 bool _do_not_unlock_if_synchronized; // Do not unlock the receiver of a synchronized method (since it was 892 // never locked) when throwing an exception. Used by interpreter only. 893 894 // JNI attach states: 895 enum JNIAttachStates { 896 _not_attaching_via_jni = 1, // thread is not attaching via JNI 897 _attaching_via_jni, // thread is attaching via JNI 898 _attached_via_jni // thread has attached via JNI 899 }; 900 901 // A regular JavaThread's _jni_attach_state is _not_attaching_via_jni. 902 // A native thread that is attaching via JNI starts with a value 903 // of _attaching_via_jni and transitions to _attached_via_jni. 904 volatile JNIAttachStates _jni_attach_state; 905 906 public: 907 // State of the stack guard pages for this thread. 908 enum StackGuardState { 909 stack_guard_unused, // not needed 910 stack_guard_reserved_disabled, 911 stack_guard_yellow_reserved_disabled,// disabled (temporarily) after stack overflow 912 stack_guard_enabled // enabled 913 }; 914 915 private: 916 917 #if INCLUDE_JVMCI 918 // The _pending_* fields below are used to communicate extra information 919 // from an uncommon trap in JVMCI compiled code to the uncommon trap handler. 920 921 // Communicates the DeoptReason and DeoptAction of the uncommon trap 922 int _pending_deoptimization; 923 924 // Specifies whether the uncommon trap is to bci 0 of a synchronized method 925 // before the monitor has been acquired. 926 bool _pending_monitorenter; 927 928 // Specifies if the DeoptReason for the last uncommon trap was Reason_transfer_to_interpreter 929 bool _pending_transfer_to_interpreter; 930 931 // Guard for re-entrant call to JVMCIRuntime::adjust_comp_level 932 bool _adjusting_comp_level; 933 934 // An object that JVMCI compiled code can use to further describe and 935 // uniquely identify the speculative optimization guarded by the uncommon trap 936 oop _pending_failed_speculation; 937 938 // These fields are mutually exclusive in terms of live ranges. 939 union { 940 // Communicates the pc at which the most recent implicit exception occurred 941 // from the signal handler to a deoptimization stub. 942 address _implicit_exception_pc; 943 944 // Communicates an alternative call target to an i2c stub from a JavaCall . 945 address _alternate_call_target; 946 } _jvmci; 947 948 // Support for high precision, thread sensitive counters in JVMCI compiled code. 949 jlong* _jvmci_counters; 950 951 public: 952 static jlong* _jvmci_old_thread_counters; 953 static void collect_counters(typeArrayOop array); 954 private: 955 #endif // INCLUDE_JVMCI 956 957 StackGuardState _stack_guard_state; 958 959 // Precompute the limit of the stack as used in stack overflow checks. 960 // We load it from here to simplify the stack overflow check in assembly. 961 address _stack_overflow_limit; 962 address _reserved_stack_activation; 963 964 // Compiler exception handling (NOTE: The _exception_oop is *NOT* the same as _pending_exception. It is 965 // used to temp. parsing values into and out of the runtime system during exception handling for compiled 966 // code) 967 volatile oop _exception_oop; // Exception thrown in compiled code 968 volatile address _exception_pc; // PC where exception happened 969 volatile address _exception_handler_pc; // PC for handler of exception 970 volatile int _is_method_handle_return; // true (== 1) if the current exception PC is a MethodHandle call site. 971 972 private: 973 // support for JNI critical regions 974 jint _jni_active_critical; // count of entries into JNI critical region 975 976 // Checked JNI: function name requires exception check 977 char* _pending_jni_exception_check_fn; 978 979 // For deadlock detection. 980 int _depth_first_number; 981 982 // JVMTI PopFrame support 983 // This is set to popframe_pending to signal that top Java frame should be popped immediately 984 int _popframe_condition; 985 986 // If reallocation of scalar replaced objects fails, we throw OOM 987 // and during exception propagation, pop the top 988 // _frames_to_pop_failed_realloc frames, the ones that reference 989 // failed reallocations. 990 int _frames_to_pop_failed_realloc; 991 992 #ifndef PRODUCT 993 int _jmp_ring_index; 994 struct { 995 // We use intptr_t instead of address so debugger doesn't try and display strings 996 intptr_t _target; 997 intptr_t _instruction; 998 const char* _file; 999 int _line; 1000 } _jmp_ring[jump_ring_buffer_size]; 1001 #endif // PRODUCT 1002 1003 #if INCLUDE_ALL_GCS 1004 // Support for G1 barriers 1005 1006 SATBMarkQueue _satb_mark_queue; // Thread-local log for SATB barrier. 1007 // Set of all such queues. 1008 static SATBMarkQueueSet _satb_mark_queue_set; 1009 1010 DirtyCardQueue _dirty_card_queue; // Thread-local log for dirty cards. 1011 // Set of all such queues. 1012 static DirtyCardQueueSet _dirty_card_queue_set; 1013 1014 void flush_barrier_queues(); 1015 #endif // INCLUDE_ALL_GCS 1016 1017 friend class VMThread; 1018 friend class ThreadWaitTransition; 1019 friend class VM_Exit; 1020 1021 void initialize(); // Initialized the instance variables 1022 1023 public: 1024 // Constructor 1025 JavaThread(bool is_attaching_via_jni = false); // for main thread and JNI attached threads 1026 JavaThread(ThreadFunction entry_point, size_t stack_size = 0); 1027 ~JavaThread(); 1028 1029 #ifdef ASSERT 1030 // verify this JavaThread hasn't be published in the Threads::list yet 1031 void verify_not_published(); 1032 #endif 1033 1034 //JNI functiontable getter/setter for JVMTI jni function table interception API. 1035 void set_jni_functions(struct JNINativeInterface_* functionTable) { 1036 _jni_environment.functions = functionTable; 1037 } 1038 struct JNINativeInterface_* get_jni_functions() { 1039 return (struct JNINativeInterface_ *)_jni_environment.functions; 1040 } 1041 1042 // This function is called at thread creation to allow 1043 // platform specific thread variables to be initialized. 1044 void cache_global_variables(); 1045 1046 // Executes Shutdown.shutdown() 1047 void invoke_shutdown_hooks(); 1048 1049 // Cleanup on thread exit 1050 enum ExitType { 1051 normal_exit, 1052 jni_detach 1053 }; 1054 void exit(bool destroy_vm, ExitType exit_type = normal_exit); 1055 1056 void cleanup_failed_attach_current_thread(); 1057 1058 // Testers 1059 virtual bool is_Java_thread() const { return true; } 1060 virtual bool can_call_java() const { return true; } 1061 1062 // Thread chain operations 1063 JavaThread* next() const { return _next; } 1064 void set_next(JavaThread* p) { _next = p; } 1065 1066 // Thread oop. threadObj() can be NULL for initial JavaThread 1067 // (or for threads attached via JNI) 1068 oop threadObj() const { return _threadObj; } 1069 void set_threadObj(oop p) { _threadObj = p; } 1070 1071 ThreadPriority java_priority() const; // Read from threadObj() 1072 1073 // Prepare thread and add to priority queue. If a priority is 1074 // not specified, use the priority of the thread object. Threads_lock 1075 // must be held while this function is called. 1076 void prepare(jobject jni_thread, ThreadPriority prio=NoPriority); 1077 void prepare_ext(); 1078 1079 void set_saved_exception_pc(address pc) { _saved_exception_pc = pc; } 1080 address saved_exception_pc() { return _saved_exception_pc; } 1081 1082 1083 ThreadFunction entry_point() const { return _entry_point; } 1084 1085 // Allocates a new Java level thread object for this thread. thread_name may be NULL. 1086 void allocate_threadObj(Handle thread_group, const char* thread_name, bool daemon, TRAPS); 1087 1088 // Last frame anchor routines 1089 1090 JavaFrameAnchor* frame_anchor(void) { return &_anchor; } 1091 1092 // last_Java_sp 1093 bool has_last_Java_frame() const { return _anchor.has_last_Java_frame(); } 1094 intptr_t* last_Java_sp() const { return _anchor.last_Java_sp(); } 1095 1096 // last_Java_pc 1097 1098 address last_Java_pc(void) { return _anchor.last_Java_pc(); } 1099 1100 // Safepoint support 1101 #if !(defined(PPC64) || defined(AARCH64)) 1102 JavaThreadState thread_state() const { return _thread_state; } 1103 void set_thread_state(JavaThreadState s) { _thread_state = s; } 1104 #else 1105 // Use membars when accessing volatile _thread_state. See 1106 // Threads::create_vm() for size checks. 1107 inline JavaThreadState thread_state() const; 1108 inline void set_thread_state(JavaThreadState s); 1109 #endif 1110 ThreadSafepointState *safepoint_state() const { return _safepoint_state; } 1111 void set_safepoint_state(ThreadSafepointState *state) { _safepoint_state = state; } 1112 bool is_at_poll_safepoint() { return _safepoint_state->is_at_poll_safepoint(); } 1113 1114 // thread has called JavaThread::exit() or is terminated 1115 bool is_exiting() { return _terminated == _thread_exiting || is_terminated(); } 1116 // thread is terminated (no longer on the threads list); we compare 1117 // against the two non-terminated values so that a freed JavaThread 1118 // will also be considered terminated. 1119 bool is_terminated() { return _terminated != _not_terminated && _terminated != _thread_exiting; } 1120 void set_terminated(TerminatedTypes t) { _terminated = t; } 1121 // special for Threads::remove() which is static: 1122 void set_terminated_value() { _terminated = _thread_terminated; } 1123 void block_if_vm_exited(); 1124 1125 bool doing_unsafe_access() { return _doing_unsafe_access; } 1126 void set_doing_unsafe_access(bool val) { _doing_unsafe_access = val; } 1127 1128 bool do_not_unlock_if_synchronized() { return _do_not_unlock_if_synchronized; } 1129 void set_do_not_unlock_if_synchronized(bool val) { _do_not_unlock_if_synchronized = val; } 1130 1131 // Suspend/resume support for JavaThread 1132 private: 1133 inline void set_ext_suspended(); 1134 inline void clear_ext_suspended(); 1135 1136 public: 1137 void java_suspend(); 1138 void java_resume(); 1139 int java_suspend_self(); 1140 1141 void check_and_wait_while_suspended() { 1142 assert(JavaThread::current() == this, "sanity check"); 1143 1144 bool do_self_suspend; 1145 do { 1146 // were we externally suspended while we were waiting? 1147 do_self_suspend = handle_special_suspend_equivalent_condition(); 1148 if (do_self_suspend) { 1149 // don't surprise the thread that suspended us by returning 1150 java_suspend_self(); 1151 set_suspend_equivalent(); 1152 } 1153 } while (do_self_suspend); 1154 } 1155 static void check_safepoint_and_suspend_for_native_trans(JavaThread *thread); 1156 // Check for async exception in addition to safepoint and suspend request. 1157 static void check_special_condition_for_native_trans(JavaThread *thread); 1158 1159 // Same as check_special_condition_for_native_trans but finishes the 1160 // transition into thread_in_Java mode so that it can potentially 1161 // block. 1162 static void check_special_condition_for_native_trans_and_transition(JavaThread *thread); 1163 1164 bool is_ext_suspend_completed(bool called_by_wait, int delay, uint32_t *bits); 1165 bool is_ext_suspend_completed_with_lock(uint32_t *bits) { 1166 MutexLockerEx ml(SR_lock(), Mutex::_no_safepoint_check_flag); 1167 // Warning: is_ext_suspend_completed() may temporarily drop the 1168 // SR_lock to allow the thread to reach a stable thread state if 1169 // it is currently in a transient thread state. 1170 return is_ext_suspend_completed(false /* !called_by_wait */, 1171 SuspendRetryDelay, bits); 1172 } 1173 1174 // We cannot allow wait_for_ext_suspend_completion() to run forever or 1175 // we could hang. SuspendRetryCount and SuspendRetryDelay are normally 1176 // passed as the count and delay parameters. Experiments with specific 1177 // calls to wait_for_ext_suspend_completion() can be done by passing 1178 // other values in the code. Experiments with all calls can be done 1179 // via the appropriate -XX options. 1180 bool wait_for_ext_suspend_completion(int count, int delay, uint32_t *bits); 1181 1182 inline void set_external_suspend(); 1183 inline void clear_external_suspend(); 1184 1185 inline void set_deopt_suspend(); 1186 inline void clear_deopt_suspend(); 1187 bool is_deopt_suspend() { return (_suspend_flags & _deopt_suspend) != 0; } 1188 1189 bool is_external_suspend() const { 1190 return (_suspend_flags & _external_suspend) != 0; 1191 } 1192 // Whenever a thread transitions from native to vm/java it must suspend 1193 // if external|deopt suspend is present. 1194 bool is_suspend_after_native() const { 1195 return (_suspend_flags & (_external_suspend | _deopt_suspend)) != 0; 1196 } 1197 1198 // external suspend request is completed 1199 bool is_ext_suspended() const { 1200 return (_suspend_flags & _ext_suspended) != 0; 1201 } 1202 1203 bool is_external_suspend_with_lock() const { 1204 MutexLockerEx ml(SR_lock(), Mutex::_no_safepoint_check_flag); 1205 return is_external_suspend(); 1206 } 1207 1208 // Special method to handle a pending external suspend request 1209 // when a suspend equivalent condition lifts. 1210 bool handle_special_suspend_equivalent_condition() { 1211 assert(is_suspend_equivalent(), 1212 "should only be called in a suspend equivalence condition"); 1213 MutexLockerEx ml(SR_lock(), Mutex::_no_safepoint_check_flag); 1214 bool ret = is_external_suspend(); 1215 if (!ret) { 1216 // not about to self-suspend so clear suspend equivalence 1217 clear_suspend_equivalent(); 1218 } 1219 // implied else: 1220 // We have a pending external suspend request so we leave the 1221 // suspend_equivalent flag set until java_suspend_self() sets 1222 // the ext_suspended flag and clears the suspend_equivalent 1223 // flag. This insures that wait_for_ext_suspend_completion() 1224 // will return consistent values. 1225 return ret; 1226 } 1227 1228 // utility methods to see if we are doing some kind of suspension 1229 bool is_being_ext_suspended() const { 1230 MutexLockerEx ml(SR_lock(), Mutex::_no_safepoint_check_flag); 1231 return is_ext_suspended() || is_external_suspend(); 1232 } 1233 1234 bool is_suspend_equivalent() const { return _suspend_equivalent; } 1235 1236 void set_suspend_equivalent() { _suspend_equivalent = true; } 1237 void clear_suspend_equivalent() { _suspend_equivalent = false; } 1238 1239 // Thread.stop support 1240 void send_thread_stop(oop throwable); 1241 AsyncRequests clear_special_runtime_exit_condition() { 1242 AsyncRequests x = _special_runtime_exit_condition; 1243 _special_runtime_exit_condition = _no_async_condition; 1244 return x; 1245 } 1246 1247 // Are any async conditions present? 1248 bool has_async_condition() { return (_special_runtime_exit_condition != _no_async_condition); } 1249 1250 void check_and_handle_async_exceptions(bool check_unsafe_error = true); 1251 1252 // these next two are also used for self-suspension and async exception support 1253 void handle_special_runtime_exit_condition(bool check_asyncs = true); 1254 1255 // Return true if JavaThread has an asynchronous condition or 1256 // if external suspension is requested. 1257 bool has_special_runtime_exit_condition() { 1258 // Because we don't use is_external_suspend_with_lock 1259 // it is possible that we won't see an asynchronous external suspend 1260 // request that has just gotten started, i.e., SR_lock grabbed but 1261 // _external_suspend field change either not made yet or not visible 1262 // yet. However, this is okay because the request is asynchronous and 1263 // we will see the new flag value the next time through. It's also 1264 // possible that the external suspend request is dropped after 1265 // we have checked is_external_suspend(), we will recheck its value 1266 // under SR_lock in java_suspend_self(). 1267 return (_special_runtime_exit_condition != _no_async_condition) || 1268 is_external_suspend() || is_deopt_suspend() || is_trace_suspend(); 1269 } 1270 1271 void set_pending_unsafe_access_error() { _special_runtime_exit_condition = _async_unsafe_access_error; } 1272 1273 inline void set_pending_async_exception(oop e); 1274 1275 // Fast-locking support 1276 bool is_lock_owned(address adr) const; 1277 1278 // Accessors for vframe array top 1279 // The linked list of vframe arrays are sorted on sp. This means when we 1280 // unpack the head must contain the vframe array to unpack. 1281 void set_vframe_array_head(vframeArray* value) { _vframe_array_head = value; } 1282 vframeArray* vframe_array_head() const { return _vframe_array_head; } 1283 1284 // Side structure for deferring update of java frame locals until deopt occurs 1285 GrowableArray<jvmtiDeferredLocalVariableSet*>* deferred_locals() const { return _deferred_locals_updates; } 1286 void set_deferred_locals(GrowableArray<jvmtiDeferredLocalVariableSet *>* vf) { _deferred_locals_updates = vf; } 1287 1288 // These only really exist to make debugging deopt problems simpler 1289 1290 void set_vframe_array_last(vframeArray* value) { _vframe_array_last = value; } 1291 vframeArray* vframe_array_last() const { return _vframe_array_last; } 1292 1293 // The special resourceMark used during deoptimization 1294 1295 void set_deopt_mark(DeoptResourceMark* value) { _deopt_mark = value; } 1296 DeoptResourceMark* deopt_mark(void) { return _deopt_mark; } 1297 1298 intptr_t* must_deopt_id() { return _must_deopt_id; } 1299 void set_must_deopt_id(intptr_t* id) { _must_deopt_id = id; } 1300 void clear_must_deopt_id() { _must_deopt_id = NULL; } 1301 1302 void set_deopt_compiled_method(CompiledMethod* nm) { _deopt_nmethod = nm; } 1303 CompiledMethod* deopt_compiled_method() { return _deopt_nmethod; } 1304 1305 Method* callee_target() const { return _callee_target; } 1306 void set_callee_target (Method* x) { _callee_target = x; } 1307 1308 // Oop results of vm runtime calls 1309 oop vm_result() const { return _vm_result; } 1310 void set_vm_result (oop x) { _vm_result = x; } 1311 1312 Metadata* vm_result_2() const { return _vm_result_2; } 1313 void set_vm_result_2 (Metadata* x) { _vm_result_2 = x; } 1314 1315 MemRegion deferred_card_mark() const { return _deferred_card_mark; } 1316 void set_deferred_card_mark(MemRegion mr) { _deferred_card_mark = mr; } 1317 1318 #if INCLUDE_JVMCI 1319 int pending_deoptimization() const { return _pending_deoptimization; } 1320 oop pending_failed_speculation() const { return _pending_failed_speculation; } 1321 bool adjusting_comp_level() const { return _adjusting_comp_level; } 1322 void set_adjusting_comp_level(bool b) { _adjusting_comp_level = b; } 1323 bool has_pending_monitorenter() const { return _pending_monitorenter; } 1324 void set_pending_monitorenter(bool b) { _pending_monitorenter = b; } 1325 void set_pending_deoptimization(int reason) { _pending_deoptimization = reason; } 1326 void set_pending_failed_speculation(oop failed_speculation) { _pending_failed_speculation = failed_speculation; } 1327 void set_pending_transfer_to_interpreter(bool b) { _pending_transfer_to_interpreter = b; } 1328 void set_jvmci_alternate_call_target(address a) { assert(_jvmci._alternate_call_target == NULL, "must be"); _jvmci._alternate_call_target = a; } 1329 void set_jvmci_implicit_exception_pc(address a) { assert(_jvmci._implicit_exception_pc == NULL, "must be"); _jvmci._implicit_exception_pc = a; } 1330 #endif // INCLUDE_JVMCI 1331 1332 // Exception handling for compiled methods 1333 oop exception_oop() const { return _exception_oop; } 1334 address exception_pc() const { return _exception_pc; } 1335 address exception_handler_pc() const { return _exception_handler_pc; } 1336 bool is_method_handle_return() const { return _is_method_handle_return == 1; } 1337 1338 void set_exception_oop(oop o) { (void)const_cast<oop&>(_exception_oop = o); } 1339 void set_exception_pc(address a) { _exception_pc = a; } 1340 void set_exception_handler_pc(address a) { _exception_handler_pc = a; } 1341 void set_is_method_handle_return(bool value) { _is_method_handle_return = value ? 1 : 0; } 1342 1343 void clear_exception_oop_and_pc() { 1344 set_exception_oop(NULL); 1345 set_exception_pc(NULL); 1346 } 1347 1348 // Stack overflow support 1349 // 1350 // (small addresses) 1351 // 1352 // -- <-- stack_end() --- 1353 // | | 1354 // | red pages | 1355 // | | 1356 // -- <-- stack_red_zone_base() | 1357 // | | 1358 // | guard 1359 // | yellow pages zone 1360 // | | 1361 // | | 1362 // -- <-- stack_yellow_zone_base() | 1363 // | | 1364 // | | 1365 // | reserved pages | 1366 // | | 1367 // -- <-- stack_reserved_zone_base() --- --- 1368 // /|\ shadow <-- stack_overflow_limit() (somewhere in here) 1369 // | zone 1370 // \|/ size 1371 // some untouched memory --- 1372 // 1373 // 1374 // -- 1375 // | 1376 // | shadow zone 1377 // | 1378 // -- 1379 // x frame n 1380 // -- 1381 // x frame n-1 1382 // x 1383 // -- 1384 // ... 1385 // 1386 // -- 1387 // x frame 0 1388 // -- <-- stack_base() 1389 // 1390 // (large addresses) 1391 // 1392 1393 private: 1394 // These values are derived from flags StackRedPages, StackYellowPages, 1395 // StackReservedPages and StackShadowPages. The zone size is determined 1396 // ergonomically if page_size > 4K. 1397 static size_t _stack_red_zone_size; 1398 static size_t _stack_yellow_zone_size; 1399 static size_t _stack_reserved_zone_size; 1400 static size_t _stack_shadow_zone_size; 1401 public: 1402 inline size_t stack_available(address cur_sp); 1403 1404 static size_t stack_red_zone_size() { 1405 assert(_stack_red_zone_size > 0, "Don't call this before the field is initialized."); 1406 return _stack_red_zone_size; 1407 } 1408 static void set_stack_red_zone_size(size_t s) { 1409 assert(is_aligned(s, os::vm_page_size()), 1410 "We can not protect if the red zone size is not page aligned."); 1411 assert(_stack_red_zone_size == 0, "This should be called only once."); 1412 _stack_red_zone_size = s; 1413 } 1414 address stack_red_zone_base() { 1415 return (address)(stack_end() + stack_red_zone_size()); 1416 } 1417 bool in_stack_red_zone(address a) { 1418 return a <= stack_red_zone_base() && a >= stack_end(); 1419 } 1420 1421 static size_t stack_yellow_zone_size() { 1422 assert(_stack_yellow_zone_size > 0, "Don't call this before the field is initialized."); 1423 return _stack_yellow_zone_size; 1424 } 1425 static void set_stack_yellow_zone_size(size_t s) { 1426 assert(is_aligned(s, os::vm_page_size()), 1427 "We can not protect if the yellow zone size is not page aligned."); 1428 assert(_stack_yellow_zone_size == 0, "This should be called only once."); 1429 _stack_yellow_zone_size = s; 1430 } 1431 1432 static size_t stack_reserved_zone_size() { 1433 // _stack_reserved_zone_size may be 0. This indicates the feature is off. 1434 return _stack_reserved_zone_size; 1435 } 1436 static void set_stack_reserved_zone_size(size_t s) { 1437 assert(is_aligned(s, os::vm_page_size()), 1438 "We can not protect if the reserved zone size is not page aligned."); 1439 assert(_stack_reserved_zone_size == 0, "This should be called only once."); 1440 _stack_reserved_zone_size = s; 1441 } 1442 address stack_reserved_zone_base() { 1443 return (address)(stack_end() + 1444 (stack_red_zone_size() + stack_yellow_zone_size() + stack_reserved_zone_size())); 1445 } 1446 bool in_stack_reserved_zone(address a) { 1447 return (a <= stack_reserved_zone_base()) && 1448 (a >= (address)((intptr_t)stack_reserved_zone_base() - stack_reserved_zone_size())); 1449 } 1450 1451 static size_t stack_yellow_reserved_zone_size() { 1452 return _stack_yellow_zone_size + _stack_reserved_zone_size; 1453 } 1454 bool in_stack_yellow_reserved_zone(address a) { 1455 return (a <= stack_reserved_zone_base()) && (a >= stack_red_zone_base()); 1456 } 1457 1458 // Size of red + yellow + reserved zones. 1459 static size_t stack_guard_zone_size() { 1460 return stack_red_zone_size() + stack_yellow_reserved_zone_size(); 1461 } 1462 1463 static size_t stack_shadow_zone_size() { 1464 assert(_stack_shadow_zone_size > 0, "Don't call this before the field is initialized."); 1465 return _stack_shadow_zone_size; 1466 } 1467 static void set_stack_shadow_zone_size(size_t s) { 1468 // The shadow area is not allocated or protected, so 1469 // it needs not be page aligned. 1470 // But the stack bang currently assumes that it is a 1471 // multiple of page size. This guarantees that the bang 1472 // loop touches all pages in the shadow zone. 1473 // This can be guaranteed differently, as well. E.g., if 1474 // the page size is a multiple of 4K, banging in 4K steps 1475 // suffices to touch all pages. (Some pages are banged 1476 // several times, though.) 1477 assert(is_aligned(s, os::vm_page_size()), 1478 "Stack bang assumes multiple of page size."); 1479 assert(_stack_shadow_zone_size == 0, "This should be called only once."); 1480 _stack_shadow_zone_size = s; 1481 } 1482 1483 void create_stack_guard_pages(); 1484 void remove_stack_guard_pages(); 1485 1486 void enable_stack_reserved_zone(); 1487 void disable_stack_reserved_zone(); 1488 void enable_stack_yellow_reserved_zone(); 1489 void disable_stack_yellow_reserved_zone(); 1490 void enable_stack_red_zone(); 1491 void disable_stack_red_zone(); 1492 1493 inline bool stack_guard_zone_unused(); 1494 inline bool stack_yellow_reserved_zone_disabled(); 1495 inline bool stack_reserved_zone_disabled(); 1496 inline bool stack_guards_enabled(); 1497 1498 address reserved_stack_activation() const { return _reserved_stack_activation; } 1499 void set_reserved_stack_activation(address addr) { 1500 assert(_reserved_stack_activation == stack_base() 1501 || _reserved_stack_activation == NULL 1502 || addr == stack_base(), "Must not be set twice"); 1503 _reserved_stack_activation = addr; 1504 } 1505 1506 // Attempt to reguard the stack after a stack overflow may have occurred. 1507 // Returns true if (a) guard pages are not needed on this thread, (b) the 1508 // pages are already guarded, or (c) the pages were successfully reguarded. 1509 // Returns false if there is not enough stack space to reguard the pages, in 1510 // which case the caller should unwind a frame and try again. The argument 1511 // should be the caller's (approximate) sp. 1512 bool reguard_stack(address cur_sp); 1513 // Similar to above but see if current stackpoint is out of the guard area 1514 // and reguard if possible. 1515 bool reguard_stack(void); 1516 1517 address stack_overflow_limit() { return _stack_overflow_limit; } 1518 void set_stack_overflow_limit() { 1519 _stack_overflow_limit = 1520 stack_end() + MAX2(JavaThread::stack_guard_zone_size(), JavaThread::stack_shadow_zone_size()); 1521 } 1522 1523 // Misc. accessors/mutators 1524 void set_do_not_unlock(void) { _do_not_unlock_if_synchronized = true; } 1525 void clr_do_not_unlock(void) { _do_not_unlock_if_synchronized = false; } 1526 bool do_not_unlock(void) { return _do_not_unlock_if_synchronized; } 1527 1528 #ifndef PRODUCT 1529 void record_jump(address target, address instr, const char* file, int line); 1530 #endif // PRODUCT 1531 1532 // For assembly stub generation 1533 static ByteSize threadObj_offset() { return byte_offset_of(JavaThread, _threadObj); } 1534 #ifndef PRODUCT 1535 static ByteSize jmp_ring_index_offset() { return byte_offset_of(JavaThread, _jmp_ring_index); } 1536 static ByteSize jmp_ring_offset() { return byte_offset_of(JavaThread, _jmp_ring); } 1537 #endif // PRODUCT 1538 static ByteSize jni_environment_offset() { return byte_offset_of(JavaThread, _jni_environment); } 1539 static ByteSize pending_jni_exception_check_fn_offset() { 1540 return byte_offset_of(JavaThread, _pending_jni_exception_check_fn); 1541 } 1542 static ByteSize last_Java_sp_offset() { 1543 return byte_offset_of(JavaThread, _anchor) + JavaFrameAnchor::last_Java_sp_offset(); 1544 } 1545 static ByteSize last_Java_pc_offset() { 1546 return byte_offset_of(JavaThread, _anchor) + JavaFrameAnchor::last_Java_pc_offset(); 1547 } 1548 static ByteSize frame_anchor_offset() { 1549 return byte_offset_of(JavaThread, _anchor); 1550 } 1551 static ByteSize callee_target_offset() { return byte_offset_of(JavaThread, _callee_target); } 1552 static ByteSize vm_result_offset() { return byte_offset_of(JavaThread, _vm_result); } 1553 static ByteSize vm_result_2_offset() { return byte_offset_of(JavaThread, _vm_result_2); } 1554 static ByteSize thread_state_offset() { return byte_offset_of(JavaThread, _thread_state); } 1555 static ByteSize saved_exception_pc_offset() { return byte_offset_of(JavaThread, _saved_exception_pc); } 1556 static ByteSize osthread_offset() { return byte_offset_of(JavaThread, _osthread); } 1557 #if INCLUDE_JVMCI 1558 static ByteSize pending_deoptimization_offset() { return byte_offset_of(JavaThread, _pending_deoptimization); } 1559 static ByteSize pending_monitorenter_offset() { return byte_offset_of(JavaThread, _pending_monitorenter); } 1560 static ByteSize pending_failed_speculation_offset() { return byte_offset_of(JavaThread, _pending_failed_speculation); } 1561 static ByteSize jvmci_alternate_call_target_offset() { return byte_offset_of(JavaThread, _jvmci._alternate_call_target); } 1562 static ByteSize jvmci_implicit_exception_pc_offset() { return byte_offset_of(JavaThread, _jvmci._implicit_exception_pc); } 1563 static ByteSize jvmci_counters_offset() { return byte_offset_of(JavaThread, _jvmci_counters); } 1564 #endif // INCLUDE_JVMCI 1565 static ByteSize exception_oop_offset() { return byte_offset_of(JavaThread, _exception_oop); } 1566 static ByteSize exception_pc_offset() { return byte_offset_of(JavaThread, _exception_pc); } 1567 static ByteSize exception_handler_pc_offset() { return byte_offset_of(JavaThread, _exception_handler_pc); } 1568 static ByteSize stack_overflow_limit_offset() { return byte_offset_of(JavaThread, _stack_overflow_limit); } 1569 static ByteSize is_method_handle_return_offset() { return byte_offset_of(JavaThread, _is_method_handle_return); } 1570 static ByteSize stack_guard_state_offset() { return byte_offset_of(JavaThread, _stack_guard_state); } 1571 static ByteSize reserved_stack_activation_offset() { return byte_offset_of(JavaThread, _reserved_stack_activation); } 1572 static ByteSize suspend_flags_offset() { return byte_offset_of(JavaThread, _suspend_flags); } 1573 1574 static ByteSize do_not_unlock_if_synchronized_offset() { return byte_offset_of(JavaThread, _do_not_unlock_if_synchronized); } 1575 static ByteSize should_post_on_exceptions_flag_offset() { 1576 return byte_offset_of(JavaThread, _should_post_on_exceptions_flag); 1577 } 1578 1579 #if INCLUDE_ALL_GCS 1580 static ByteSize satb_mark_queue_offset() { return byte_offset_of(JavaThread, _satb_mark_queue); } 1581 static ByteSize dirty_card_queue_offset() { return byte_offset_of(JavaThread, _dirty_card_queue); } 1582 #endif // INCLUDE_ALL_GCS 1583 1584 // Returns the jni environment for this thread 1585 JNIEnv* jni_environment() { return &_jni_environment; } 1586 1587 static JavaThread* thread_from_jni_environment(JNIEnv* env) { 1588 JavaThread *thread_from_jni_env = (JavaThread*)((intptr_t)env - in_bytes(jni_environment_offset())); 1589 // Only return NULL if thread is off the thread list; starting to 1590 // exit should not return NULL. 1591 if (thread_from_jni_env->is_terminated()) { 1592 thread_from_jni_env->block_if_vm_exited(); 1593 return NULL; 1594 } else { 1595 return thread_from_jni_env; 1596 } 1597 } 1598 1599 // JNI critical regions. These can nest. 1600 bool in_critical() { return _jni_active_critical > 0; } 1601 bool in_last_critical() { return _jni_active_critical == 1; } 1602 void enter_critical() { 1603 assert(Thread::current() == this || 1604 (Thread::current()->is_VM_thread() && 1605 SafepointSynchronize::is_synchronizing()), 1606 "this must be current thread or synchronizing"); 1607 _jni_active_critical++; 1608 } 1609 void exit_critical() { 1610 assert(Thread::current() == this, "this must be current thread"); 1611 _jni_active_critical--; 1612 assert(_jni_active_critical >= 0, "JNI critical nesting problem?"); 1613 } 1614 1615 // Checked JNI: is the programmer required to check for exceptions, if so specify 1616 // which function name. Returning to a Java frame should implicitly clear the 1617 // pending check, this is done for Native->Java transitions (i.e. user JNI code). 1618 // VM->Java transistions are not cleared, it is expected that JNI code enclosed 1619 // within ThreadToNativeFromVM makes proper exception checks (i.e. VM internal). 1620 bool is_pending_jni_exception_check() const { return _pending_jni_exception_check_fn != NULL; } 1621 void clear_pending_jni_exception_check() { _pending_jni_exception_check_fn = NULL; } 1622 const char* get_pending_jni_exception_check() const { return _pending_jni_exception_check_fn; } 1623 void set_pending_jni_exception_check(const char* fn_name) { _pending_jni_exception_check_fn = (char*) fn_name; } 1624 1625 // For deadlock detection 1626 int depth_first_number() { return _depth_first_number; } 1627 void set_depth_first_number(int dfn) { _depth_first_number = dfn; } 1628 1629 private: 1630 void set_monitor_chunks(MonitorChunk* monitor_chunks) { _monitor_chunks = monitor_chunks; } 1631 1632 public: 1633 MonitorChunk* monitor_chunks() const { return _monitor_chunks; } 1634 void add_monitor_chunk(MonitorChunk* chunk); 1635 void remove_monitor_chunk(MonitorChunk* chunk); 1636 bool in_deopt_handler() const { return _in_deopt_handler > 0; } 1637 void inc_in_deopt_handler() { _in_deopt_handler++; } 1638 void dec_in_deopt_handler() { 1639 assert(_in_deopt_handler > 0, "mismatched deopt nesting"); 1640 if (_in_deopt_handler > 0) { // robustness 1641 _in_deopt_handler--; 1642 } 1643 } 1644 1645 private: 1646 void set_entry_point(ThreadFunction entry_point) { _entry_point = entry_point; } 1647 1648 public: 1649 1650 // Frame iteration; calls the function f for all frames on the stack 1651 void frames_do(void f(frame*, const RegisterMap*)); 1652 1653 // Memory operations 1654 void oops_do(OopClosure* f, CodeBlobClosure* cf); 1655 1656 // Sweeper operations 1657 virtual void nmethods_do(CodeBlobClosure* cf); 1658 1659 // RedefineClasses Support 1660 void metadata_do(void f(Metadata*)); 1661 1662 // Misc. operations 1663 char* name() const { return (char*)get_thread_name(); } 1664 void print_on(outputStream* st) const; 1665 void print_value(); 1666 void print_thread_state_on(outputStream*) const PRODUCT_RETURN; 1667 void print_thread_state() const PRODUCT_RETURN; 1668 void print_on_error(outputStream* st, char* buf, int buflen) const; 1669 void print_name_on_error(outputStream* st, char* buf, int buflen) const; 1670 void verify(); 1671 const char* get_thread_name() const; 1672 private: 1673 // factor out low-level mechanics for use in both normal and error cases 1674 const char* get_thread_name_string(char* buf = NULL, int buflen = 0) const; 1675 public: 1676 const char* get_threadgroup_name() const; 1677 const char* get_parent_name() const; 1678 1679 // Accessing frames 1680 frame last_frame() { 1681 _anchor.make_walkable(this); 1682 return pd_last_frame(); 1683 } 1684 javaVFrame* last_java_vframe(RegisterMap* reg_map); 1685 1686 // Returns method at 'depth' java or native frames down the stack 1687 // Used for security checks 1688 Klass* security_get_caller_class(int depth); 1689 1690 // Print stack trace in external format 1691 void print_stack_on(outputStream* st); 1692 void print_stack() { print_stack_on(tty); } 1693 1694 // Print stack traces in various internal formats 1695 void trace_stack() PRODUCT_RETURN; 1696 void trace_stack_from(vframe* start_vf) PRODUCT_RETURN; 1697 void trace_frames() PRODUCT_RETURN; 1698 void trace_oops() PRODUCT_RETURN; 1699 1700 // Print an annotated view of the stack frames 1701 void print_frame_layout(int depth = 0, bool validate_only = false) NOT_DEBUG_RETURN; 1702 void validate_frame_layout() { 1703 print_frame_layout(0, true); 1704 } 1705 1706 // Returns the number of stack frames on the stack 1707 int depth() const; 1708 1709 // Function for testing deoptimization 1710 void deoptimize(); 1711 void make_zombies(); 1712 1713 void deoptimized_wrt_marked_nmethods(); 1714 1715 // Profiling operation (see fprofile.cpp) 1716 public: 1717 bool profile_last_Java_frame(frame* fr); 1718 1719 private: 1720 ThreadProfiler* _thread_profiler; 1721 private: 1722 friend class FlatProfiler; // uses both [gs]et_thread_profiler. 1723 friend class FlatProfilerTask; // uses get_thread_profiler. 1724 friend class ThreadProfilerMark; // uses get_thread_profiler. 1725 ThreadProfiler* get_thread_profiler() { return _thread_profiler; } 1726 ThreadProfiler* set_thread_profiler(ThreadProfiler* tp) { 1727 ThreadProfiler* result = _thread_profiler; 1728 _thread_profiler = tp; 1729 return result; 1730 } 1731 1732 public: 1733 // Returns the running thread as a JavaThread 1734 static inline JavaThread* current(); 1735 1736 // Returns the active Java thread. Do not use this if you know you are calling 1737 // from a JavaThread, as it's slower than JavaThread::current. If called from 1738 // the VMThread, it also returns the JavaThread that instigated the VMThread's 1739 // operation. You may not want that either. 1740 static JavaThread* active(); 1741 1742 inline CompilerThread* as_CompilerThread(); 1743 1744 public: 1745 virtual void run(); 1746 void thread_main_inner(); 1747 1748 private: 1749 // PRIVILEGED STACK 1750 PrivilegedElement* _privileged_stack_top; 1751 GrowableArray<oop>* _array_for_gc; 1752 public: 1753 1754 // Returns the privileged_stack information. 1755 PrivilegedElement* privileged_stack_top() const { return _privileged_stack_top; } 1756 void set_privileged_stack_top(PrivilegedElement *e) { _privileged_stack_top = e; } 1757 void register_array_for_gc(GrowableArray<oop>* array) { _array_for_gc = array; } 1758 1759 public: 1760 // Thread local information maintained by JVMTI. 1761 void set_jvmti_thread_state(JvmtiThreadState *value) { _jvmti_thread_state = value; } 1762 // A JvmtiThreadState is lazily allocated. This jvmti_thread_state() 1763 // getter is used to get this JavaThread's JvmtiThreadState if it has 1764 // one which means NULL can be returned. JvmtiThreadState::state_for() 1765 // is used to get the specified JavaThread's JvmtiThreadState if it has 1766 // one or it allocates a new JvmtiThreadState for the JavaThread and 1767 // returns it. JvmtiThreadState::state_for() will return NULL only if 1768 // the specified JavaThread is exiting. 1769 JvmtiThreadState *jvmti_thread_state() const { return _jvmti_thread_state; } 1770 static ByteSize jvmti_thread_state_offset() { return byte_offset_of(JavaThread, _jvmti_thread_state); } 1771 void set_jvmti_get_loaded_classes_closure(JvmtiGetLoadedClassesClosure* value) { _jvmti_get_loaded_classes_closure = value; } 1772 JvmtiGetLoadedClassesClosure* get_jvmti_get_loaded_classes_closure() const { return _jvmti_get_loaded_classes_closure; } 1773 1774 // JVMTI PopFrame support 1775 // Setting and clearing popframe_condition 1776 // All of these enumerated values are bits. popframe_pending 1777 // indicates that a PopFrame() has been requested and not yet been 1778 // completed. popframe_processing indicates that that PopFrame() is in 1779 // the process of being completed. popframe_force_deopt_reexecution_bit 1780 // indicates that special handling is required when returning to a 1781 // deoptimized caller. 1782 enum PopCondition { 1783 popframe_inactive = 0x00, 1784 popframe_pending_bit = 0x01, 1785 popframe_processing_bit = 0x02, 1786 popframe_force_deopt_reexecution_bit = 0x04 1787 }; 1788 PopCondition popframe_condition() { return (PopCondition) _popframe_condition; } 1789 void set_popframe_condition(PopCondition c) { _popframe_condition = c; } 1790 void set_popframe_condition_bit(PopCondition c) { _popframe_condition |= c; } 1791 void clear_popframe_condition() { _popframe_condition = popframe_inactive; } 1792 static ByteSize popframe_condition_offset() { return byte_offset_of(JavaThread, _popframe_condition); } 1793 bool has_pending_popframe() { return (popframe_condition() & popframe_pending_bit) != 0; } 1794 bool popframe_forcing_deopt_reexecution() { return (popframe_condition() & popframe_force_deopt_reexecution_bit) != 0; } 1795 void clear_popframe_forcing_deopt_reexecution() { _popframe_condition &= ~popframe_force_deopt_reexecution_bit; } 1796 #ifdef CC_INTERP 1797 bool pop_frame_pending(void) { return ((_popframe_condition & popframe_pending_bit) != 0); } 1798 void clr_pop_frame_pending(void) { _popframe_condition = popframe_inactive; } 1799 bool pop_frame_in_process(void) { return ((_popframe_condition & popframe_processing_bit) != 0); } 1800 void set_pop_frame_in_process(void) { _popframe_condition |= popframe_processing_bit; } 1801 void clr_pop_frame_in_process(void) { _popframe_condition &= ~popframe_processing_bit; } 1802 #endif 1803 1804 int frames_to_pop_failed_realloc() const { return _frames_to_pop_failed_realloc; } 1805 void set_frames_to_pop_failed_realloc(int nb) { _frames_to_pop_failed_realloc = nb; } 1806 void dec_frames_to_pop_failed_realloc() { _frames_to_pop_failed_realloc--; } 1807 1808 private: 1809 // Saved incoming arguments to popped frame. 1810 // Used only when popped interpreted frame returns to deoptimized frame. 1811 void* _popframe_preserved_args; 1812 int _popframe_preserved_args_size; 1813 1814 public: 1815 void popframe_preserve_args(ByteSize size_in_bytes, void* start); 1816 void* popframe_preserved_args(); 1817 ByteSize popframe_preserved_args_size(); 1818 WordSize popframe_preserved_args_size_in_words(); 1819 void popframe_free_preserved_args(); 1820 1821 1822 private: 1823 JvmtiThreadState *_jvmti_thread_state; 1824 JvmtiGetLoadedClassesClosure* _jvmti_get_loaded_classes_closure; 1825 1826 // Used by the interpreter in fullspeed mode for frame pop, method 1827 // entry, method exit and single stepping support. This field is 1828 // only set to non-zero by the VM_EnterInterpOnlyMode VM operation. 1829 // It can be set to zero asynchronously (i.e., without a VM operation 1830 // or a lock) so we have to be very careful. 1831 int _interp_only_mode; 1832 1833 public: 1834 // used by the interpreter for fullspeed debugging support (see above) 1835 static ByteSize interp_only_mode_offset() { return byte_offset_of(JavaThread, _interp_only_mode); } 1836 bool is_interp_only_mode() { return (_interp_only_mode != 0); } 1837 int get_interp_only_mode() { return _interp_only_mode; } 1838 void increment_interp_only_mode() { ++_interp_only_mode; } 1839 void decrement_interp_only_mode() { --_interp_only_mode; } 1840 1841 // support for cached flag that indicates whether exceptions need to be posted for this thread 1842 // if this is false, we can avoid deoptimizing when events are thrown 1843 // this gets set to reflect whether jvmtiExport::post_exception_throw would actually do anything 1844 private: 1845 int _should_post_on_exceptions_flag; 1846 1847 public: 1848 int should_post_on_exceptions_flag() { return _should_post_on_exceptions_flag; } 1849 void set_should_post_on_exceptions_flag(int val) { _should_post_on_exceptions_flag = val; } 1850 1851 private: 1852 ThreadStatistics *_thread_stat; 1853 1854 public: 1855 ThreadStatistics* get_thread_stat() const { return _thread_stat; } 1856 1857 // Return a blocker object for which this thread is blocked parking. 1858 oop current_park_blocker(); 1859 1860 private: 1861 static size_t _stack_size_at_create; 1862 1863 public: 1864 static inline size_t stack_size_at_create(void) { 1865 return _stack_size_at_create; 1866 } 1867 static inline void set_stack_size_at_create(size_t value) { 1868 _stack_size_at_create = value; 1869 } 1870 1871 #if INCLUDE_ALL_GCS 1872 // SATB marking queue support 1873 SATBMarkQueue& satb_mark_queue() { return _satb_mark_queue; } 1874 static SATBMarkQueueSet& satb_mark_queue_set() { 1875 return _satb_mark_queue_set; 1876 } 1877 1878 // Dirty card queue support 1879 DirtyCardQueue& dirty_card_queue() { return _dirty_card_queue; } 1880 static DirtyCardQueueSet& dirty_card_queue_set() { 1881 return _dirty_card_queue_set; 1882 } 1883 #endif // INCLUDE_ALL_GCS 1884 1885 // This method initializes the SATB and dirty card queues before a 1886 // JavaThread is added to the Java thread list. Right now, we don't 1887 // have to do anything to the dirty card queue (it should have been 1888 // activated when the thread was created), but we have to activate 1889 // the SATB queue if the thread is created while a marking cycle is 1890 // in progress. The activation / de-activation of the SATB queues at 1891 // the beginning / end of a marking cycle is done during safepoints 1892 // so we have to make sure this method is called outside one to be 1893 // able to safely read the active field of the SATB queue set. Right 1894 // now, it is called just before the thread is added to the Java 1895 // thread list in the Threads::add() method. That method is holding 1896 // the Threads_lock which ensures we are outside a safepoint. We 1897 // cannot do the obvious and set the active field of the SATB queue 1898 // when the thread is created given that, in some cases, safepoints 1899 // might happen between the JavaThread constructor being called and the 1900 // thread being added to the Java thread list (an example of this is 1901 // when the structure for the DestroyJavaVM thread is created). 1902 #if INCLUDE_ALL_GCS 1903 void initialize_queues(); 1904 #else // INCLUDE_ALL_GCS 1905 void initialize_queues() { } 1906 #endif // INCLUDE_ALL_GCS 1907 1908 // Machine dependent stuff 1909 #include OS_CPU_HEADER(thread) 1910 1911 public: 1912 void set_blocked_on_compilation(bool value) { 1913 _blocked_on_compilation = value; 1914 } 1915 1916 bool blocked_on_compilation() { 1917 return _blocked_on_compilation; 1918 } 1919 protected: 1920 bool _blocked_on_compilation; 1921 1922 1923 // JSR166 per-thread parker 1924 private: 1925 Parker* _parker; 1926 public: 1927 Parker* parker() { return _parker; } 1928 1929 // Biased locking support 1930 private: 1931 GrowableArray<MonitorInfo*>* _cached_monitor_info; 1932 public: 1933 GrowableArray<MonitorInfo*>* cached_monitor_info() { return _cached_monitor_info; } 1934 void set_cached_monitor_info(GrowableArray<MonitorInfo*>* info) { _cached_monitor_info = info; } 1935 1936 // clearing/querying jni attach status 1937 bool is_attaching_via_jni() const { return _jni_attach_state == _attaching_via_jni; } 1938 bool has_attached_via_jni() const { return is_attaching_via_jni() || _jni_attach_state == _attached_via_jni; } 1939 inline void set_done_attaching_via_jni(); 1940 }; 1941 1942 // Inline implementation of JavaThread::current 1943 inline JavaThread* JavaThread::current() { 1944 Thread* thread = Thread::current(); 1945 assert(thread->is_Java_thread(), "just checking"); 1946 return (JavaThread*)thread; 1947 } 1948 1949 inline CompilerThread* JavaThread::as_CompilerThread() { 1950 assert(is_Compiler_thread(), "just checking"); 1951 return (CompilerThread*)this; 1952 } 1953 1954 // Dedicated thread to sweep the code cache 1955 class CodeCacheSweeperThread : public JavaThread { 1956 CompiledMethod* _scanned_compiled_method; // nmethod being scanned by the sweeper 1957 public: 1958 CodeCacheSweeperThread(); 1959 // Track the nmethod currently being scanned by the sweeper 1960 void set_scanned_compiled_method(CompiledMethod* cm) { 1961 assert(_scanned_compiled_method == NULL || cm == NULL, "should reset to NULL before writing a new value"); 1962 _scanned_compiled_method = cm; 1963 } 1964 1965 // Hide sweeper thread from external view. 1966 bool is_hidden_from_external_view() const { return true; } 1967 1968 bool is_Code_cache_sweeper_thread() const { return true; } 1969 1970 // Prevent GC from unloading _scanned_compiled_method 1971 void oops_do(OopClosure* f, CodeBlobClosure* cf); 1972 void nmethods_do(CodeBlobClosure* cf); 1973 }; 1974 1975 // A thread used for Compilation. 1976 class CompilerThread : public JavaThread { 1977 friend class VMStructs; 1978 private: 1979 CompilerCounters* _counters; 1980 1981 ciEnv* _env; 1982 CompileLog* _log; 1983 CompileTask* _task; 1984 CompileQueue* _queue; 1985 BufferBlob* _buffer_blob; 1986 1987 AbstractCompiler* _compiler; 1988 1989 public: 1990 1991 static CompilerThread* current(); 1992 1993 CompilerThread(CompileQueue* queue, CompilerCounters* counters); 1994 1995 bool is_Compiler_thread() const { return true; } 1996 1997 virtual bool can_call_java() const; 1998 1999 // Hide native compiler threads from external view. 2000 bool is_hidden_from_external_view() const { return !can_call_java(); } 2001 2002 void set_compiler(AbstractCompiler* c) { _compiler = c; } 2003 AbstractCompiler* compiler() const { return _compiler; } 2004 2005 CompileQueue* queue() const { return _queue; } 2006 CompilerCounters* counters() const { return _counters; } 2007 2008 // Get/set the thread's compilation environment. 2009 ciEnv* env() { return _env; } 2010 void set_env(ciEnv* env) { _env = env; } 2011 2012 BufferBlob* get_buffer_blob() const { return _buffer_blob; } 2013 void set_buffer_blob(BufferBlob* b) { _buffer_blob = b; } 2014 2015 // Get/set the thread's logging information 2016 CompileLog* log() { return _log; } 2017 void init_log(CompileLog* log) { 2018 // Set once, for good. 2019 assert(_log == NULL, "set only once"); 2020 _log = log; 2021 } 2022 2023 #ifndef PRODUCT 2024 private: 2025 IdealGraphPrinter *_ideal_graph_printer; 2026 public: 2027 IdealGraphPrinter *ideal_graph_printer() { return _ideal_graph_printer; } 2028 void set_ideal_graph_printer(IdealGraphPrinter *n) { _ideal_graph_printer = n; } 2029 #endif 2030 2031 // Get/set the thread's current task 2032 CompileTask* task() { return _task; } 2033 void set_task(CompileTask* task) { _task = task; } 2034 }; 2035 2036 inline CompilerThread* CompilerThread::current() { 2037 return JavaThread::current()->as_CompilerThread(); 2038 } 2039 2040 // The active thread queue. It also keeps track of the current used 2041 // thread priorities. 2042 class Threads: AllStatic { 2043 friend class VMStructs; 2044 private: 2045 static JavaThread* _thread_list; 2046 static int _number_of_threads; 2047 static int _number_of_non_daemon_threads; 2048 static int _return_code; 2049 static int _thread_claim_parity; 2050 #ifdef ASSERT 2051 static bool _vm_complete; 2052 #endif 2053 2054 static void initialize_java_lang_classes(JavaThread* main_thread, TRAPS); 2055 static void initialize_jsr292_core_classes(TRAPS); 2056 public: 2057 // Thread management 2058 // force_daemon is a concession to JNI, where we may need to add a 2059 // thread to the thread list before allocating its thread object 2060 static void add(JavaThread* p, bool force_daemon = false); 2061 static void remove(JavaThread* p); 2062 static bool includes(JavaThread* p); 2063 static JavaThread* first() { return _thread_list; } 2064 static void threads_do(ThreadClosure* tc); 2065 2066 // Initializes the vm and creates the vm thread 2067 static jint create_vm(JavaVMInitArgs* args, bool* canTryAgain); 2068 static void convert_vm_init_libraries_to_agents(); 2069 static void create_vm_init_libraries(); 2070 static void create_vm_init_agents(); 2071 static void shutdown_vm_agents(); 2072 static bool destroy_vm(); 2073 // Supported VM versions via JNI 2074 // Includes JNI_VERSION_1_1 2075 static jboolean is_supported_jni_version_including_1_1(jint version); 2076 // Does not include JNI_VERSION_1_1 2077 static jboolean is_supported_jni_version(jint version); 2078 2079 // The "thread claim parity" provides a way for threads to be claimed 2080 // by parallel worker tasks. 2081 // 2082 // Each thread contains a a "parity" field. A task will claim the 2083 // thread only if its parity field is the same as the global parity, 2084 // which is updated by calling change_thread_claim_parity(). 2085 // 2086 // For this to work change_thread_claim_parity() needs to be called 2087 // exactly once in sequential code before starting parallel tasks 2088 // that should claim threads. 2089 // 2090 // New threads get their parity set to 0 and change_thread_claim_parity() 2091 // never set the global parity to 0. 2092 static int thread_claim_parity() { return _thread_claim_parity; } 2093 static void change_thread_claim_parity(); 2094 static void assert_all_threads_claimed() NOT_DEBUG_RETURN; 2095 2096 // Apply "f->do_oop" to all root oops in all threads. 2097 // This version may only be called by sequential code. 2098 static void oops_do(OopClosure* f, CodeBlobClosure* cf); 2099 // This version may be called by sequential or parallel code. 2100 static void possibly_parallel_oops_do(bool is_par, OopClosure* f, CodeBlobClosure* cf); 2101 // This creates a list of GCTasks, one per thread. 2102 static void create_thread_roots_tasks(GCTaskQueue* q); 2103 // This creates a list of GCTasks, one per thread, for marking objects. 2104 static void create_thread_roots_marking_tasks(GCTaskQueue* q); 2105 2106 // Apply "f->do_oop" to roots in all threads that 2107 // are part of compiled frames 2108 static void compiled_frame_oops_do(OopClosure* f, CodeBlobClosure* cf); 2109 2110 static void convert_hcode_pointers(); 2111 static void restore_hcode_pointers(); 2112 2113 // Sweeper 2114 static void nmethods_do(CodeBlobClosure* cf); 2115 2116 // RedefineClasses support 2117 static void metadata_do(void f(Metadata*)); 2118 static void metadata_handles_do(void f(Metadata*)); 2119 2120 #ifdef ASSERT 2121 static bool is_vm_complete() { return _vm_complete; } 2122 #endif 2123 2124 // Verification 2125 static void verify(); 2126 static void print_on(outputStream* st, bool print_stacks, bool internal_format, bool print_concurrent_locks); 2127 static void print(bool print_stacks, bool internal_format) { 2128 // this function is only used by debug.cpp 2129 print_on(tty, print_stacks, internal_format, false /* no concurrent lock printed */); 2130 } 2131 static void print_on_error(outputStream* st, Thread* current, char* buf, int buflen); 2132 static void print_on_error(Thread* this_thread, outputStream* st, Thread* current, char* buf, 2133 int buflen, bool* found_current); 2134 static void print_threads_compiling(outputStream* st, char* buf, int buflen); 2135 2136 // Get Java threads that are waiting to enter a monitor. If doLock 2137 // is true, then Threads_lock is grabbed as needed. Otherwise, the 2138 // VM needs to be at a safepoint. 2139 static GrowableArray<JavaThread*>* get_pending_threads(int count, 2140 address monitor, bool doLock); 2141 2142 // Get owning Java thread from the monitor's owner field. If doLock 2143 // is true, then Threads_lock is grabbed as needed. Otherwise, the 2144 // VM needs to be at a safepoint. 2145 static JavaThread *owning_thread_from_monitor_owner(address owner, 2146 bool doLock); 2147 2148 // Number of threads on the active threads list 2149 static int number_of_threads() { return _number_of_threads; } 2150 // Number of non-daemon threads on the active threads list 2151 static int number_of_non_daemon_threads() { return _number_of_non_daemon_threads; } 2152 2153 // Deoptimizes all frames tied to marked nmethods 2154 static void deoptimized_wrt_marked_nmethods(); 2155 2156 static JavaThread* find_java_thread_from_java_tid(jlong java_tid); 2157 2158 }; 2159 2160 2161 // Thread iterator 2162 class ThreadClosure: public StackObj { 2163 public: 2164 virtual void do_thread(Thread* thread) = 0; 2165 }; 2166 2167 class SignalHandlerMark: public StackObj { 2168 private: 2169 Thread* _thread; 2170 public: 2171 SignalHandlerMark(Thread* t) { 2172 _thread = t; 2173 if (_thread) _thread->enter_signal_handler(); 2174 } 2175 ~SignalHandlerMark() { 2176 if (_thread) _thread->leave_signal_handler(); 2177 _thread = NULL; 2178 } 2179 }; 2180 2181 2182 #endif // SHARE_VM_RUNTIME_THREAD_HPP