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/handshake.hpp" 35 #include "runtime/javaFrameAnchor.hpp" 36 #include "runtime/jniHandles.hpp" 37 #include "runtime/mutexLocker.hpp" 38 #include "runtime/os.hpp" 39 #include "runtime/osThread.hpp" 40 #include "runtime/park.hpp" 41 #include "runtime/safepoint.hpp" 42 #include "runtime/stubRoutines.hpp" 43 #include "runtime/threadLocalStorage.hpp" 44 #include "runtime/thread_ext.hpp" 45 #include "runtime/unhandledOops.hpp" 46 #include "trace/traceBackend.hpp" 47 #include "trace/traceMacros.hpp" 48 #include "utilities/align.hpp" 49 #include "utilities/exceptions.hpp" 50 #include "utilities/macros.hpp" 51 #if INCLUDE_ALL_GCS 52 #include "gc/g1/dirtyCardQueue.hpp" 53 #include "gc/g1/satbMarkQueue.hpp" 54 #endif // INCLUDE_ALL_GCS 55 #ifdef ZERO 56 # include "stack_zero.hpp" 57 #endif 58 59 class ThreadSafepointState; 60 61 class JvmtiThreadState; 62 class JvmtiGetLoadedClassesClosure; 63 class ThreadStatistics; 64 class ConcurrentLocksDump; 65 class ParkEvent; 66 class Parker; 67 68 class ciEnv; 69 class CompileThread; 70 class CompileLog; 71 class CompileTask; 72 class CompileQueue; 73 class CompilerCounters; 74 class vframeArray; 75 76 class DeoptResourceMark; 77 class jvmtiDeferredLocalVariableSet; 78 79 class GCTaskQueue; 80 class ThreadClosure; 81 class IdealGraphPrinter; 82 83 class Metadata; 84 template <class T, MEMFLAGS F> class ChunkedList; 85 typedef ChunkedList<Metadata*, mtInternal> MetadataOnStackBuffer; 86 87 DEBUG_ONLY(class ResourceMark;) 88 89 class WorkerThread; 90 91 // Class hierarchy 92 // - Thread 93 // - NamedThread 94 // - VMThread 95 // - ConcurrentGCThread 96 // - WorkerThread 97 // - GangWorker 98 // - GCTaskThread 99 // - JavaThread 100 // - various subclasses eg CompilerThread, ServiceThread 101 // - WatcherThread 102 103 class Thread: public ThreadShadow { 104 friend class VMStructs; 105 friend class JVMCIVMStructs; 106 private: 107 108 #ifndef USE_LIBRARY_BASED_TLS_ONLY 109 // Current thread is maintained as a thread-local variable 110 static THREAD_LOCAL_DECL Thread* _thr_current; 111 #endif 112 113 // Exception handling 114 // (Note: _pending_exception and friends are in ThreadShadow) 115 //oop _pending_exception; // pending exception for current thread 116 // const char* _exception_file; // file information for exception (debugging only) 117 // int _exception_line; // line information for exception (debugging only) 118 protected: 119 // Support for forcing alignment of thread objects for biased locking 120 void* _real_malloc_address; 121 public: 122 void* operator new(size_t size) throw() { return allocate(size, true); } 123 void* operator new(size_t size, const std::nothrow_t& nothrow_constant) throw() { 124 return allocate(size, false); } 125 void operator delete(void* p); 126 127 protected: 128 static void* allocate(size_t size, bool throw_excpt, MEMFLAGS flags = mtThread); 129 private: 130 131 // *************************************************************** 132 // Suspend and resume support 133 // *************************************************************** 134 // 135 // VM suspend/resume no longer exists - it was once used for various 136 // things including safepoints but was deprecated and finally removed 137 // in Java 7. Because VM suspension was considered "internal" Java-level 138 // suspension was considered "external", and this legacy naming scheme 139 // remains. 140 // 141 // External suspend/resume requests come from JVM_SuspendThread, 142 // JVM_ResumeThread, JVMTI SuspendThread, and finally JVMTI 143 // ResumeThread. External 144 // suspend requests cause _external_suspend to be set and external 145 // resume requests cause _external_suspend to be cleared. 146 // External suspend requests do not nest on top of other external 147 // suspend requests. The higher level APIs reject suspend requests 148 // for already suspended threads. 149 // 150 // The external_suspend 151 // flag is checked by has_special_runtime_exit_condition() and java thread 152 // will self-suspend when handle_special_runtime_exit_condition() is 153 // called. Most uses of the _thread_blocked state in JavaThreads are 154 // considered the same as being externally suspended; if the blocking 155 // condition lifts, the JavaThread will self-suspend. Other places 156 // where VM checks for external_suspend include: 157 // + mutex granting (do not enter monitors when thread is suspended) 158 // + state transitions from _thread_in_native 159 // 160 // In general, java_suspend() does not wait for an external suspend 161 // request to complete. When it returns, the only guarantee is that 162 // the _external_suspend field is true. 163 // 164 // wait_for_ext_suspend_completion() is used to wait for an external 165 // suspend request to complete. External suspend requests are usually 166 // followed by some other interface call that requires the thread to 167 // be quiescent, e.g., GetCallTrace(). By moving the "wait time" into 168 // the interface that requires quiescence, we give the JavaThread a 169 // chance to self-suspend before we need it to be quiescent. This 170 // improves overall suspend/query performance. 171 // 172 // _suspend_flags controls the behavior of java_ suspend/resume. 173 // It must be set under the protection of SR_lock. Read from the flag is 174 // OK without SR_lock as long as the value is only used as a hint. 175 // (e.g., check _external_suspend first without lock and then recheck 176 // inside SR_lock and finish the suspension) 177 // 178 // _suspend_flags is also overloaded for other "special conditions" so 179 // that a single check indicates whether any special action is needed 180 // eg. for async exceptions. 181 // ------------------------------------------------------------------- 182 // Notes: 183 // 1. The suspend/resume logic no longer uses ThreadState in OSThread 184 // but we still update its value to keep other part of the system (mainly 185 // JVMTI) happy. ThreadState is legacy code (see notes in 186 // osThread.hpp). 187 // 188 // 2. It would be more natural if set_external_suspend() is private and 189 // part of java_suspend(), but that probably would affect the suspend/query 190 // performance. Need more investigation on this. 191 192 // suspend/resume lock: used for self-suspend 193 Monitor* _SR_lock; 194 195 protected: 196 enum SuspendFlags { 197 // NOTE: avoid using the sign-bit as cc generates different test code 198 // when the sign-bit is used, and sometimes incorrectly - see CR 6398077 199 200 _external_suspend = 0x20000000U, // thread is asked to self suspend 201 _ext_suspended = 0x40000000U, // thread has self-suspended 202 _deopt_suspend = 0x10000000U, // thread needs to self suspend for deopt 203 204 _has_async_exception = 0x00000001U, // there is a pending async exception 205 _critical_native_unlock = 0x00000002U, // Must call back to unlock JNI critical lock 206 207 _trace_flag = 0x00000004U // call tracing backend 208 }; 209 210 // various suspension related flags - atomically updated 211 // overloaded for async exception checking in check_special_condition_for_native_trans. 212 volatile uint32_t _suspend_flags; 213 214 private: 215 int _num_nested_signal; 216 217 DEBUG_ONLY(bool _suspendible_thread;) 218 219 public: 220 void enter_signal_handler() { _num_nested_signal++; } 221 void leave_signal_handler() { _num_nested_signal--; } 222 bool is_inside_signal_handler() const { return _num_nested_signal > 0; } 223 224 #ifdef ASSERT 225 void set_suspendible_thread() { 226 _suspendible_thread = true; 227 } 228 229 void clear_suspendible_thread() { 230 _suspendible_thread = false; 231 } 232 233 bool is_suspendible_thread() { return _suspendible_thread; } 234 #endif 235 236 private: 237 // Active_handles points to a block of handles 238 JNIHandleBlock* _active_handles; 239 240 // One-element thread local free list 241 JNIHandleBlock* _free_handle_block; 242 243 // Point to the last handle mark 244 HandleMark* _last_handle_mark; 245 246 // The parity of the last strong_roots iteration in which this thread was 247 // claimed as a task. 248 jint _oops_do_parity; 249 250 public: 251 void set_last_handle_mark(HandleMark* mark) { _last_handle_mark = mark; } 252 HandleMark* last_handle_mark() const { return _last_handle_mark; } 253 private: 254 255 // debug support for checking if code does allow safepoints or not 256 // GC points in the VM can happen because of allocation, invoking a VM operation, or blocking on 257 // mutex, or blocking on an object synchronizer (Java locking). 258 // If !allow_safepoint(), then an assertion failure will happen in any of the above cases 259 // If !allow_allocation(), then an assertion failure will happen during allocation 260 // (Hence, !allow_safepoint() => !allow_allocation()). 261 // 262 // The two classes NoSafepointVerifier and No_Allocation_Verifier are used to set these counters. 263 // 264 NOT_PRODUCT(int _allow_safepoint_count;) // If 0, thread allow a safepoint to happen 265 debug_only(int _allow_allocation_count;) // If 0, the thread is allowed to allocate oops. 266 267 // Used by SkipGCALot class. 268 NOT_PRODUCT(bool _skip_gcalot;) // Should we elide gc-a-lot? 269 270 friend class NoAllocVerifier; 271 friend class NoSafepointVerifier; 272 friend class PauseNoSafepointVerifier; 273 friend class GCLocker; 274 275 volatile void* _polling_page; // Thread local polling page 276 277 ThreadLocalAllocBuffer _tlab; // Thread-local eden 278 jlong _allocated_bytes; // Cumulative number of bytes allocated on 279 // the Java heap 280 281 mutable TRACE_DATA _trace_data; // Thread-local data for tracing 282 283 ThreadExt _ext; 284 285 int _vm_operation_started_count; // VM_Operation support 286 int _vm_operation_completed_count; // VM_Operation support 287 288 ObjectMonitor* _current_pending_monitor; // ObjectMonitor this thread 289 // is waiting to lock 290 bool _current_pending_monitor_is_from_java; // locking is from Java code 291 292 // ObjectMonitor on which this thread called Object.wait() 293 ObjectMonitor* _current_waiting_monitor; 294 295 // Private thread-local objectmonitor list - a simple cache organized as a SLL. 296 public: 297 ObjectMonitor* omFreeList; 298 int omFreeCount; // length of omFreeList 299 int omFreeProvision; // reload chunk size 300 ObjectMonitor* omInUseList; // SLL to track monitors in circulation 301 int omInUseCount; // length of omInUseList 302 303 #ifdef ASSERT 304 private: 305 bool _visited_for_critical_count; 306 307 public: 308 void set_visited_for_critical_count(bool z) { _visited_for_critical_count = z; } 309 bool was_visited_for_critical_count() const { return _visited_for_critical_count; } 310 #endif 311 312 public: 313 enum { 314 is_definitely_current_thread = true 315 }; 316 317 // Constructor 318 Thread(); 319 virtual ~Thread(); 320 321 // Manage Thread::current() 322 void initialize_thread_current(); 323 void clear_thread_current(); // TLS cleanup needed before threads terminate 324 325 public: 326 // thread entry point 327 virtual void run(); 328 329 // Testers 330 virtual bool is_VM_thread() const { return false; } 331 virtual bool is_Java_thread() const { return false; } 332 virtual bool is_Compiler_thread() const { return false; } 333 virtual bool is_Code_cache_sweeper_thread() const { return false; } 334 virtual bool is_hidden_from_external_view() const { return false; } 335 virtual bool is_jvmti_agent_thread() const { return false; } 336 // True iff the thread can perform GC operations at a safepoint. 337 // Generally will be true only of VM thread and parallel GC WorkGang 338 // threads. 339 virtual bool is_GC_task_thread() const { return false; } 340 virtual bool is_Watcher_thread() const { return false; } 341 virtual bool is_ConcurrentGC_thread() const { return false; } 342 virtual bool is_Named_thread() const { return false; } 343 virtual bool is_Worker_thread() const { return false; } 344 345 // Can this thread make Java upcalls 346 virtual bool can_call_java() const { return false; } 347 348 // Casts 349 virtual WorkerThread* as_Worker_thread() const { return NULL; } 350 351 virtual char* name() const { return (char*)"Unknown thread"; } 352 353 // Returns the current thread (ASSERTS if NULL) 354 static inline Thread* current(); 355 // Returns the current thread, or NULL if not attached 356 static inline Thread* current_or_null(); 357 // Returns the current thread, or NULL if not attached, and is 358 // safe for use from signal-handlers 359 static inline Thread* current_or_null_safe(); 360 361 // Common thread operations 362 static void set_priority(Thread* thread, ThreadPriority priority); 363 static ThreadPriority get_priority(const Thread* const thread); 364 static void start(Thread* thread); 365 static void interrupt(Thread* thr); 366 static bool is_interrupted(Thread* thr, bool clear_interrupted); 367 368 void set_native_thread_name(const char *name) { 369 assert(Thread::current() == this, "set_native_thread_name can only be called on the current thread"); 370 os::set_native_thread_name(name); 371 } 372 373 ObjectMonitor** omInUseList_addr() { return (ObjectMonitor **)&omInUseList; } 374 Monitor* SR_lock() const { return _SR_lock; } 375 376 bool has_async_exception() const { return (_suspend_flags & _has_async_exception) != 0; } 377 378 inline void set_suspend_flag(SuspendFlags f); 379 inline void clear_suspend_flag(SuspendFlags f); 380 381 inline void set_has_async_exception(); 382 inline void clear_has_async_exception(); 383 384 bool do_critical_native_unlock() const { return (_suspend_flags & _critical_native_unlock) != 0; } 385 386 inline void set_critical_native_unlock(); 387 inline void clear_critical_native_unlock(); 388 389 inline void set_trace_flag(); 390 inline void clear_trace_flag(); 391 392 // Support for Unhandled Oop detection 393 // Add the field for both, fastdebug and debug, builds to keep 394 // Thread's fields layout the same. 395 // Note: CHECK_UNHANDLED_OOPS is defined only for fastdebug build. 396 #ifdef CHECK_UNHANDLED_OOPS 397 private: 398 UnhandledOops* _unhandled_oops; 399 #elif defined(ASSERT) 400 private: 401 void* _unhandled_oops; 402 #endif 403 #ifdef CHECK_UNHANDLED_OOPS 404 public: 405 UnhandledOops* unhandled_oops() { return _unhandled_oops; } 406 // Mark oop safe for gc. It may be stack allocated but won't move. 407 void allow_unhandled_oop(oop *op) { 408 if (CheckUnhandledOops) unhandled_oops()->allow_unhandled_oop(op); 409 } 410 // Clear oops at safepoint so crashes point to unhandled oop violator 411 void clear_unhandled_oops() { 412 if (CheckUnhandledOops) unhandled_oops()->clear_unhandled_oops(); 413 } 414 #endif // CHECK_UNHANDLED_OOPS 415 416 public: 417 #ifndef PRODUCT 418 bool skip_gcalot() { return _skip_gcalot; } 419 void set_skip_gcalot(bool v) { _skip_gcalot = v; } 420 #endif 421 422 // Installs a pending exception to be inserted later 423 static void send_async_exception(oop thread_oop, oop java_throwable); 424 425 // Resource area 426 ResourceArea* resource_area() const { return _resource_area; } 427 void set_resource_area(ResourceArea* area) { _resource_area = area; } 428 429 OSThread* osthread() const { return _osthread; } 430 void set_osthread(OSThread* thread) { _osthread = thread; } 431 432 // JNI handle support 433 JNIHandleBlock* active_handles() const { return _active_handles; } 434 void set_active_handles(JNIHandleBlock* block) { _active_handles = block; } 435 JNIHandleBlock* free_handle_block() const { return _free_handle_block; } 436 void set_free_handle_block(JNIHandleBlock* block) { _free_handle_block = block; } 437 438 // Internal handle support 439 HandleArea* handle_area() const { return _handle_area; } 440 void set_handle_area(HandleArea* area) { _handle_area = area; } 441 442 GrowableArray<Metadata*>* metadata_handles() const { return _metadata_handles; } 443 void set_metadata_handles(GrowableArray<Metadata*>* handles){ _metadata_handles = handles; } 444 445 // Thread-Local Allocation Buffer (TLAB) support 446 ThreadLocalAllocBuffer& tlab() { return _tlab; } 447 void initialize_tlab() { 448 if (UseTLAB) { 449 tlab().initialize(); 450 } 451 } 452 453 jlong allocated_bytes() { return _allocated_bytes; } 454 void set_allocated_bytes(jlong value) { _allocated_bytes = value; } 455 void incr_allocated_bytes(jlong size) { _allocated_bytes += size; } 456 inline jlong cooked_allocated_bytes(); 457 458 TRACE_DEFINE_THREAD_TRACE_DATA_OFFSET; 459 TRACE_DATA* trace_data() const { return &_trace_data; } 460 bool is_trace_suspend() { return (_suspend_flags & _trace_flag) != 0; } 461 462 const ThreadExt& ext() const { return _ext; } 463 ThreadExt& ext() { return _ext; } 464 465 // VM operation support 466 int vm_operation_ticket() { return ++_vm_operation_started_count; } 467 int vm_operation_completed_count() { return _vm_operation_completed_count; } 468 void increment_vm_operation_completed_count() { _vm_operation_completed_count++; } 469 470 // For tracking the heavyweight monitor the thread is pending on. 471 ObjectMonitor* current_pending_monitor() { 472 return _current_pending_monitor; 473 } 474 void set_current_pending_monitor(ObjectMonitor* monitor) { 475 _current_pending_monitor = monitor; 476 } 477 void set_current_pending_monitor_is_from_java(bool from_java) { 478 _current_pending_monitor_is_from_java = from_java; 479 } 480 bool current_pending_monitor_is_from_java() { 481 return _current_pending_monitor_is_from_java; 482 } 483 484 // For tracking the ObjectMonitor on which this thread called Object.wait() 485 ObjectMonitor* current_waiting_monitor() { 486 return _current_waiting_monitor; 487 } 488 void set_current_waiting_monitor(ObjectMonitor* monitor) { 489 _current_waiting_monitor = monitor; 490 } 491 492 // GC support 493 // Apply "f->do_oop" to all root oops in "this". 494 // Used by JavaThread::oops_do. 495 // Apply "cf->do_code_blob" (if !NULL) to all code blobs active in frames 496 virtual void oops_do(OopClosure* f, CodeBlobClosure* cf); 497 498 // Handles the parallel case for the method below. 499 private: 500 bool claim_oops_do_par_case(int collection_parity); 501 public: 502 // Requires that "collection_parity" is that of the current roots 503 // iteration. If "is_par" is false, sets the parity of "this" to 504 // "collection_parity", and returns "true". If "is_par" is true, 505 // uses an atomic instruction to set the current threads parity to 506 // "collection_parity", if it is not already. Returns "true" iff the 507 // calling thread does the update, this indicates that the calling thread 508 // has claimed the thread's stack as a root groop in the current 509 // collection. 510 bool claim_oops_do(bool is_par, int collection_parity) { 511 if (!is_par) { 512 _oops_do_parity = collection_parity; 513 return true; 514 } else { 515 return claim_oops_do_par_case(collection_parity); 516 } 517 } 518 519 // jvmtiRedefineClasses support 520 void metadata_handles_do(void f(Metadata*)); 521 522 // Used by fast lock support 523 virtual bool is_lock_owned(address adr) const; 524 525 // Check if address is in the stack of the thread (not just for locks). 526 // Warning: the method can only be used on the running thread 527 bool is_in_stack(address adr) const; 528 // Check if address is in the usable part of the stack (excludes protected 529 // guard pages) 530 bool is_in_usable_stack(address adr) const; 531 532 // Sets this thread as starting thread. Returns failure if thread 533 // creation fails due to lack of memory, too many threads etc. 534 bool set_as_starting_thread(); 535 536 protected: 537 // OS data associated with the thread 538 OSThread* _osthread; // Platform-specific thread information 539 540 // Thread local resource area for temporary allocation within the VM 541 ResourceArea* _resource_area; 542 543 DEBUG_ONLY(ResourceMark* _current_resource_mark;) 544 545 // Thread local handle area for allocation of handles within the VM 546 HandleArea* _handle_area; 547 GrowableArray<Metadata*>* _metadata_handles; 548 549 // Support for stack overflow handling, get_thread, etc. 550 address _stack_base; 551 size_t _stack_size; 552 uintptr_t _self_raw_id; // used by get_thread (mutable) 553 int _lgrp_id; 554 555 volatile void** polling_page_addr() { return &_polling_page; } 556 557 public: 558 // Stack overflow support 559 address stack_base() const { assert(_stack_base != NULL,"Sanity check"); return _stack_base; } 560 void set_stack_base(address base) { _stack_base = base; } 561 size_t stack_size() const { return _stack_size; } 562 void set_stack_size(size_t size) { _stack_size = size; } 563 address stack_end() const { return stack_base() - stack_size(); } 564 void record_stack_base_and_size(); 565 566 bool on_local_stack(address adr) const { 567 // QQQ this has knowledge of direction, ought to be a stack method 568 return (_stack_base >= adr && adr >= stack_end()); 569 } 570 571 uintptr_t self_raw_id() { return _self_raw_id; } 572 void set_self_raw_id(uintptr_t value) { _self_raw_id = value; } 573 574 int lgrp_id() const { return _lgrp_id; } 575 void set_lgrp_id(int value) { _lgrp_id = value; } 576 577 // Printing 578 virtual void print_on(outputStream* st) const; 579 void print() const { print_on(tty); } 580 virtual void print_on_error(outputStream* st, char* buf, int buflen) const; 581 void print_value_on(outputStream* st) const; 582 583 // Debug-only code 584 #ifdef ASSERT 585 private: 586 // Deadlock detection support for Mutex locks. List of locks own by thread. 587 Monitor* _owned_locks; 588 // Mutex::set_owner_implementation is the only place where _owned_locks is modified, 589 // thus the friendship 590 friend class Mutex; 591 friend class Monitor; 592 593 public: 594 void print_owned_locks_on(outputStream* st) const; 595 void print_owned_locks() const { print_owned_locks_on(tty); } 596 Monitor* owned_locks() const { return _owned_locks; } 597 bool owns_locks() const { return owned_locks() != NULL; } 598 bool owns_locks_but_compiled_lock() const; 599 int oops_do_parity() const { return _oops_do_parity; } 600 601 // Deadlock detection 602 bool allow_allocation() { return _allow_allocation_count == 0; } 603 ResourceMark* current_resource_mark() { return _current_resource_mark; } 604 void set_current_resource_mark(ResourceMark* rm) { _current_resource_mark = rm; } 605 #endif 606 607 void check_for_valid_safepoint_state(bool potential_vm_operation) PRODUCT_RETURN; 608 609 private: 610 volatile int _jvmti_env_iteration_count; 611 612 public: 613 void entering_jvmti_env_iteration() { ++_jvmti_env_iteration_count; } 614 void leaving_jvmti_env_iteration() { --_jvmti_env_iteration_count; } 615 bool is_inside_jvmti_env_iteration() { return _jvmti_env_iteration_count > 0; } 616 617 // Code generation 618 static ByteSize exception_file_offset() { return byte_offset_of(Thread, _exception_file); } 619 static ByteSize exception_line_offset() { return byte_offset_of(Thread, _exception_line); } 620 static ByteSize active_handles_offset() { return byte_offset_of(Thread, _active_handles); } 621 622 static ByteSize stack_base_offset() { return byte_offset_of(Thread, _stack_base); } 623 static ByteSize stack_size_offset() { return byte_offset_of(Thread, _stack_size); } 624 625 static ByteSize polling_page_offset() { return byte_offset_of(Thread, _polling_page); } 626 627 #define TLAB_FIELD_OFFSET(name) \ 628 static ByteSize tlab_##name##_offset() { return byte_offset_of(Thread, _tlab) + ThreadLocalAllocBuffer::name##_offset(); } 629 630 TLAB_FIELD_OFFSET(start) 631 TLAB_FIELD_OFFSET(end) 632 TLAB_FIELD_OFFSET(top) 633 TLAB_FIELD_OFFSET(pf_top) 634 TLAB_FIELD_OFFSET(size) // desired_size 635 TLAB_FIELD_OFFSET(refill_waste_limit) 636 TLAB_FIELD_OFFSET(number_of_refills) 637 TLAB_FIELD_OFFSET(fast_refill_waste) 638 TLAB_FIELD_OFFSET(slow_allocations) 639 640 #undef TLAB_FIELD_OFFSET 641 642 static ByteSize allocated_bytes_offset() { return byte_offset_of(Thread, _allocated_bytes); } 643 644 public: 645 volatile intptr_t _Stalled; 646 volatile int _TypeTag; 647 ParkEvent * _ParkEvent; // for synchronized() 648 ParkEvent * _SleepEvent; // for Thread.sleep 649 ParkEvent * _MutexEvent; // for native internal Mutex/Monitor 650 ParkEvent * _MuxEvent; // for low-level muxAcquire-muxRelease 651 int NativeSyncRecursion; // diagnostic 652 653 volatile int _OnTrap; // Resume-at IP delta 654 jint _hashStateW; // Marsaglia Shift-XOR thread-local RNG 655 jint _hashStateX; // thread-specific hashCode generator state 656 jint _hashStateY; 657 jint _hashStateZ; 658 void * _schedctl; 659 660 661 volatile jint rng[4]; // RNG for spin loop 662 663 // Low-level leaf-lock primitives used to implement synchronization 664 // and native monitor-mutex infrastructure. 665 // Not for general synchronization use. 666 static void SpinAcquire(volatile int * Lock, const char * Name); 667 static void SpinRelease(volatile int * Lock); 668 static void muxAcquire(volatile intptr_t * Lock, const char * Name); 669 static void muxAcquireW(volatile intptr_t * Lock, ParkEvent * ev); 670 static void muxRelease(volatile intptr_t * Lock); 671 }; 672 673 // Inline implementation of Thread::current() 674 inline Thread* Thread::current() { 675 Thread* current = current_or_null(); 676 assert(current != NULL, "Thread::current() called on detached thread"); 677 return current; 678 } 679 680 inline Thread* Thread::current_or_null() { 681 #ifndef USE_LIBRARY_BASED_TLS_ONLY 682 return _thr_current; 683 #else 684 if (ThreadLocalStorage::is_initialized()) { 685 return ThreadLocalStorage::thread(); 686 } 687 return NULL; 688 #endif 689 } 690 691 inline Thread* Thread::current_or_null_safe() { 692 if (ThreadLocalStorage::is_initialized()) { 693 return ThreadLocalStorage::thread(); 694 } 695 return NULL; 696 } 697 698 // Name support for threads. non-JavaThread subclasses with multiple 699 // uniquely named instances should derive from this. 700 class NamedThread: public Thread { 701 friend class VMStructs; 702 enum { 703 max_name_len = 64 704 }; 705 private: 706 char* _name; 707 // log JavaThread being processed by oops_do 708 JavaThread* _processed_thread; 709 uint _gc_id; // The current GC id when a thread takes part in GC 710 711 public: 712 NamedThread(); 713 ~NamedThread(); 714 // May only be called once per thread. 715 void set_name(const char* format, ...) ATTRIBUTE_PRINTF(2, 3); 716 void initialize_named_thread(); 717 virtual bool is_Named_thread() const { return true; } 718 virtual char* name() const { return _name == NULL ? (char*)"Unknown Thread" : _name; } 719 JavaThread *processed_thread() { return _processed_thread; } 720 void set_processed_thread(JavaThread *thread) { _processed_thread = thread; } 721 virtual void print_on(outputStream* st) const; 722 723 void set_gc_id(uint gc_id) { _gc_id = gc_id; } 724 uint gc_id() { return _gc_id; } 725 }; 726 727 // Worker threads are named and have an id of an assigned work. 728 class WorkerThread: public NamedThread { 729 private: 730 uint _id; 731 public: 732 WorkerThread() : _id(0) { } 733 virtual bool is_Worker_thread() const { return true; } 734 735 virtual WorkerThread* as_Worker_thread() const { 736 assert(is_Worker_thread(), "Dubious cast to WorkerThread*?"); 737 return (WorkerThread*) this; 738 } 739 740 void set_id(uint work_id) { _id = work_id; } 741 uint id() const { return _id; } 742 }; 743 744 // A single WatcherThread is used for simulating timer interrupts. 745 class WatcherThread: public Thread { 746 friend class VMStructs; 747 public: 748 virtual void run(); 749 750 private: 751 static WatcherThread* _watcher_thread; 752 753 static bool _startable; 754 // volatile due to at least one lock-free read 755 volatile static bool _should_terminate; 756 public: 757 enum SomeConstants { 758 delay_interval = 10 // interrupt delay in milliseconds 759 }; 760 761 // Constructor 762 WatcherThread(); 763 764 // No destruction allowed 765 ~WatcherThread() { 766 guarantee(false, "WatcherThread deletion must fix the race with VM termination"); 767 } 768 769 // Tester 770 bool is_Watcher_thread() const { return true; } 771 772 // Printing 773 char* name() const { return (char*)"VM Periodic Task Thread"; } 774 void print_on(outputStream* st) const; 775 void unpark(); 776 777 // Returns the single instance of WatcherThread 778 static WatcherThread* watcher_thread() { return _watcher_thread; } 779 780 // Create and start the single instance of WatcherThread, or stop it on shutdown 781 static void start(); 782 static void stop(); 783 // Only allow start once the VM is sufficiently initialized 784 // Otherwise the first task to enroll will trigger the start 785 static void make_startable(); 786 private: 787 int sleep() const; 788 }; 789 790 791 class CompilerThread; 792 793 typedef void (*ThreadFunction)(JavaThread*, TRAPS); 794 795 class JavaThread: public Thread { 796 friend class VMStructs; 797 friend class JVMCIVMStructs; 798 friend class WhiteBox; 799 private: 800 JavaThread* _next; // The next thread in the Threads list 801 oop _threadObj; // The Java level thread object 802 803 #ifdef ASSERT 804 private: 805 int _java_call_counter; 806 807 public: 808 int java_call_counter() { return _java_call_counter; } 809 void inc_java_call_counter() { _java_call_counter++; } 810 void dec_java_call_counter() { 811 assert(_java_call_counter > 0, "Invalid nesting of JavaCallWrapper"); 812 _java_call_counter--; 813 } 814 private: // restore original namespace restriction 815 #endif // ifdef ASSERT 816 817 #ifndef PRODUCT 818 public: 819 enum { 820 jump_ring_buffer_size = 16 821 }; 822 private: // restore original namespace restriction 823 #endif 824 825 JavaFrameAnchor _anchor; // Encapsulation of current java frame and it state 826 827 ThreadFunction _entry_point; 828 829 JNIEnv _jni_environment; 830 831 // Deopt support 832 DeoptResourceMark* _deopt_mark; // Holds special ResourceMark for deoptimization 833 834 intptr_t* _must_deopt_id; // id of frame that needs to be deopted once we 835 // transition out of native 836 CompiledMethod* _deopt_nmethod; // CompiledMethod that is currently being deoptimized 837 vframeArray* _vframe_array_head; // Holds the heap of the active vframeArrays 838 vframeArray* _vframe_array_last; // Holds last vFrameArray we popped 839 // Because deoptimization is lazy we must save jvmti requests to set locals 840 // in compiled frames until we deoptimize and we have an interpreter frame. 841 // This holds the pointer to array (yeah like there might be more than one) of 842 // description of compiled vframes that have locals that need to be updated. 843 GrowableArray<jvmtiDeferredLocalVariableSet*>* _deferred_locals_updates; 844 845 // Handshake value for fixing 6243940. We need a place for the i2c 846 // adapter to store the callee Method*. This value is NEVER live 847 // across a gc point so it does NOT have to be gc'd 848 // The handshake is open ended since we can't be certain that it will 849 // be NULLed. This is because we rarely ever see the race and end up 850 // in handle_wrong_method which is the backend of the handshake. See 851 // code in i2c adapters and handle_wrong_method. 852 853 Method* _callee_target; 854 855 // Used to pass back results to the interpreter or generated code running Java code. 856 oop _vm_result; // oop result is GC-preserved 857 Metadata* _vm_result_2; // non-oop result 858 859 // See ReduceInitialCardMarks: this holds the precise space interval of 860 // the most recent slow path allocation for which compiled code has 861 // elided card-marks for performance along the fast-path. 862 MemRegion _deferred_card_mark; 863 864 MonitorChunk* _monitor_chunks; // Contains the off stack monitors 865 // allocated during deoptimization 866 // and by JNI_MonitorEnter/Exit 867 868 // Async. requests support 869 enum AsyncRequests { 870 _no_async_condition = 0, 871 _async_exception, 872 _async_unsafe_access_error 873 }; 874 AsyncRequests _special_runtime_exit_condition; // Enum indicating pending async. request 875 oop _pending_async_exception; 876 877 // Safepoint support 878 public: // Expose _thread_state for SafeFetchInt() 879 volatile JavaThreadState _thread_state; 880 private: 881 ThreadSafepointState *_safepoint_state; // Holds information about a thread during a safepoint 882 address _saved_exception_pc; // Saved pc of instruction where last implicit exception happened 883 884 // JavaThread termination support 885 enum TerminatedTypes { 886 _not_terminated = 0xDEAD - 2, 887 _thread_exiting, // JavaThread::exit() has been called for this thread 888 _thread_terminated, // JavaThread is removed from thread list 889 _vm_exited // JavaThread is still executing native code, but VM is terminated 890 // only VM_Exit can set _vm_exited 891 }; 892 893 // In general a JavaThread's _terminated field transitions as follows: 894 // 895 // _not_terminated => _thread_exiting => _thread_terminated 896 // 897 // _vm_exited is a special value to cover the case of a JavaThread 898 // executing native code after the VM itself is terminated. 899 volatile TerminatedTypes _terminated; 900 // suspend/resume support 901 volatile bool _suspend_equivalent; // Suspend equivalent condition 902 jint _in_deopt_handler; // count of deoptimization 903 // handlers thread is in 904 volatile bool _doing_unsafe_access; // Thread may fault due to unsafe access 905 bool _do_not_unlock_if_synchronized; // Do not unlock the receiver of a synchronized method (since it was 906 // never locked) when throwing an exception. Used by interpreter only. 907 908 // JNI attach states: 909 enum JNIAttachStates { 910 _not_attaching_via_jni = 1, // thread is not attaching via JNI 911 _attaching_via_jni, // thread is attaching via JNI 912 _attached_via_jni // thread has attached via JNI 913 }; 914 915 // A regular JavaThread's _jni_attach_state is _not_attaching_via_jni. 916 // A native thread that is attaching via JNI starts with a value 917 // of _attaching_via_jni and transitions to _attached_via_jni. 918 volatile JNIAttachStates _jni_attach_state; 919 920 public: 921 // State of the stack guard pages for this thread. 922 enum StackGuardState { 923 stack_guard_unused, // not needed 924 stack_guard_reserved_disabled, 925 stack_guard_yellow_reserved_disabled,// disabled (temporarily) after stack overflow 926 stack_guard_enabled // enabled 927 }; 928 929 private: 930 931 #if INCLUDE_JVMCI 932 // The _pending_* fields below are used to communicate extra information 933 // from an uncommon trap in JVMCI compiled code to the uncommon trap handler. 934 935 // Communicates the DeoptReason and DeoptAction of the uncommon trap 936 int _pending_deoptimization; 937 938 // Specifies whether the uncommon trap is to bci 0 of a synchronized method 939 // before the monitor has been acquired. 940 bool _pending_monitorenter; 941 942 // Specifies if the DeoptReason for the last uncommon trap was Reason_transfer_to_interpreter 943 bool _pending_transfer_to_interpreter; 944 945 // Guard for re-entrant call to JVMCIRuntime::adjust_comp_level 946 bool _adjusting_comp_level; 947 948 // An object that JVMCI compiled code can use to further describe and 949 // uniquely identify the speculative optimization guarded by the uncommon trap 950 oop _pending_failed_speculation; 951 952 // These fields are mutually exclusive in terms of live ranges. 953 union { 954 // Communicates the pc at which the most recent implicit exception occurred 955 // from the signal handler to a deoptimization stub. 956 address _implicit_exception_pc; 957 958 // Communicates an alternative call target to an i2c stub from a JavaCall . 959 address _alternate_call_target; 960 } _jvmci; 961 962 // Support for high precision, thread sensitive counters in JVMCI compiled code. 963 jlong* _jvmci_counters; 964 965 public: 966 static jlong* _jvmci_old_thread_counters; 967 static void collect_counters(typeArrayOop array); 968 private: 969 #endif // INCLUDE_JVMCI 970 971 StackGuardState _stack_guard_state; 972 973 // Precompute the limit of the stack as used in stack overflow checks. 974 // We load it from here to simplify the stack overflow check in assembly. 975 address _stack_overflow_limit; 976 address _reserved_stack_activation; 977 978 // Compiler exception handling (NOTE: The _exception_oop is *NOT* the same as _pending_exception. It is 979 // used to temp. parsing values into and out of the runtime system during exception handling for compiled 980 // code) 981 volatile oop _exception_oop; // Exception thrown in compiled code 982 volatile address _exception_pc; // PC where exception happened 983 volatile address _exception_handler_pc; // PC for handler of exception 984 volatile int _is_method_handle_return; // true (== 1) if the current exception PC is a MethodHandle call site. 985 986 private: 987 // support for JNI critical regions 988 jint _jni_active_critical; // count of entries into JNI critical region 989 990 // Checked JNI: function name requires exception check 991 char* _pending_jni_exception_check_fn; 992 993 // For deadlock detection. 994 int _depth_first_number; 995 996 // JVMTI PopFrame support 997 // This is set to popframe_pending to signal that top Java frame should be popped immediately 998 int _popframe_condition; 999 1000 // If reallocation of scalar replaced objects fails, we throw OOM 1001 // and during exception propagation, pop the top 1002 // _frames_to_pop_failed_realloc frames, the ones that reference 1003 // failed reallocations. 1004 int _frames_to_pop_failed_realloc; 1005 1006 #ifndef PRODUCT 1007 int _jmp_ring_index; 1008 struct { 1009 // We use intptr_t instead of address so debugger doesn't try and display strings 1010 intptr_t _target; 1011 intptr_t _instruction; 1012 const char* _file; 1013 int _line; 1014 } _jmp_ring[jump_ring_buffer_size]; 1015 #endif // PRODUCT 1016 1017 #if INCLUDE_ALL_GCS 1018 // Support for G1 barriers 1019 1020 SATBMarkQueue _satb_mark_queue; // Thread-local log for SATB barrier. 1021 // Set of all such queues. 1022 static SATBMarkQueueSet _satb_mark_queue_set; 1023 1024 DirtyCardQueue _dirty_card_queue; // Thread-local log for dirty cards. 1025 // Set of all such queues. 1026 static DirtyCardQueueSet _dirty_card_queue_set; 1027 1028 void flush_barrier_queues(); 1029 #endif // INCLUDE_ALL_GCS 1030 1031 friend class VMThread; 1032 friend class ThreadWaitTransition; 1033 friend class VM_Exit; 1034 1035 void initialize(); // Initialized the instance variables 1036 1037 public: 1038 // Constructor 1039 JavaThread(bool is_attaching_via_jni = false); // for main thread and JNI attached threads 1040 JavaThread(ThreadFunction entry_point, size_t stack_size = 0); 1041 ~JavaThread(); 1042 1043 #ifdef ASSERT 1044 // verify this JavaThread hasn't be published in the Threads::list yet 1045 void verify_not_published(); 1046 #endif 1047 1048 //JNI functiontable getter/setter for JVMTI jni function table interception API. 1049 void set_jni_functions(struct JNINativeInterface_* functionTable) { 1050 _jni_environment.functions = functionTable; 1051 } 1052 struct JNINativeInterface_* get_jni_functions() { 1053 return (struct JNINativeInterface_ *)_jni_environment.functions; 1054 } 1055 1056 // This function is called at thread creation to allow 1057 // platform specific thread variables to be initialized. 1058 void cache_global_variables(); 1059 1060 // Executes Shutdown.shutdown() 1061 void invoke_shutdown_hooks(); 1062 1063 // Cleanup on thread exit 1064 enum ExitType { 1065 normal_exit, 1066 jni_detach 1067 }; 1068 void exit(bool destroy_vm, ExitType exit_type = normal_exit); 1069 1070 void cleanup_failed_attach_current_thread(); 1071 1072 // Testers 1073 virtual bool is_Java_thread() const { return true; } 1074 virtual bool can_call_java() const { return true; } 1075 1076 // Thread chain operations 1077 JavaThread* next() const { return _next; } 1078 void set_next(JavaThread* p) { _next = p; } 1079 1080 // Thread oop. threadObj() can be NULL for initial JavaThread 1081 // (or for threads attached via JNI) 1082 oop threadObj() const { return _threadObj; } 1083 void set_threadObj(oop p) { _threadObj = p; } 1084 1085 ThreadPriority java_priority() const; // Read from threadObj() 1086 1087 // Prepare thread and add to priority queue. If a priority is 1088 // not specified, use the priority of the thread object. Threads_lock 1089 // must be held while this function is called. 1090 void prepare(jobject jni_thread, ThreadPriority prio=NoPriority); 1091 void prepare_ext(); 1092 1093 void set_saved_exception_pc(address pc) { _saved_exception_pc = pc; } 1094 address saved_exception_pc() { return _saved_exception_pc; } 1095 1096 1097 ThreadFunction entry_point() const { return _entry_point; } 1098 1099 // Allocates a new Java level thread object for this thread. thread_name may be NULL. 1100 void allocate_threadObj(Handle thread_group, const char* thread_name, bool daemon, TRAPS); 1101 1102 // Last frame anchor routines 1103 1104 JavaFrameAnchor* frame_anchor(void) { return &_anchor; } 1105 1106 // last_Java_sp 1107 bool has_last_Java_frame() const { return _anchor.has_last_Java_frame(); } 1108 intptr_t* last_Java_sp() const { return _anchor.last_Java_sp(); } 1109 1110 // last_Java_pc 1111 1112 address last_Java_pc(void) { return _anchor.last_Java_pc(); } 1113 1114 // Safepoint support 1115 #if !(defined(PPC64) || defined(AARCH64)) 1116 JavaThreadState thread_state() const { return _thread_state; } 1117 void set_thread_state(JavaThreadState s) { _thread_state = s; } 1118 #else 1119 // Use membars when accessing volatile _thread_state. See 1120 // Threads::create_vm() for size checks. 1121 inline JavaThreadState thread_state() const; 1122 inline void set_thread_state(JavaThreadState s); 1123 #endif 1124 ThreadSafepointState *safepoint_state() const { return _safepoint_state; } 1125 void set_safepoint_state(ThreadSafepointState *state) { _safepoint_state = state; } 1126 bool is_at_poll_safepoint() { return _safepoint_state->is_at_poll_safepoint(); } 1127 1128 // thread has called JavaThread::exit() or is terminated 1129 bool is_exiting() { return _terminated == _thread_exiting || is_terminated(); } 1130 // thread is terminated (no longer on the threads list); we compare 1131 // against the two non-terminated values so that a freed JavaThread 1132 // will also be considered terminated. 1133 bool is_terminated() { return _terminated != _not_terminated && _terminated != _thread_exiting; } 1134 void set_terminated(TerminatedTypes t) { _terminated = t; } 1135 // special for Threads::remove() which is static: 1136 void set_terminated_value() { _terminated = _thread_terminated; } 1137 void block_if_vm_exited(); 1138 1139 bool doing_unsafe_access() { return _doing_unsafe_access; } 1140 void set_doing_unsafe_access(bool val) { _doing_unsafe_access = val; } 1141 1142 bool do_not_unlock_if_synchronized() { return _do_not_unlock_if_synchronized; } 1143 void set_do_not_unlock_if_synchronized(bool val) { _do_not_unlock_if_synchronized = val; } 1144 1145 inline void set_polling_page(void* poll_value); 1146 inline void* get_polling_page(); 1147 1148 private: 1149 // Support for thread handshake operations 1150 HandshakeState _handshake; 1151 public: 1152 void set_handshake_operation(HandshakeOperation* op) { 1153 _handshake.set_operation(this, op); 1154 } 1155 1156 bool has_handshake() const { 1157 return _handshake.has_operation(); 1158 } 1159 1160 void cancel_handshake() { 1161 _handshake.cancel(this); 1162 } 1163 1164 void handshake_process_by_self() { 1165 _handshake.process_by_self(this); 1166 } 1167 1168 void handshake_process_by_vmthread() { 1169 _handshake.process_by_vmthread(this); 1170 } 1171 1172 // Suspend/resume support for JavaThread 1173 private: 1174 inline void set_ext_suspended(); 1175 inline void clear_ext_suspended(); 1176 1177 public: 1178 void java_suspend(); 1179 void java_resume(); 1180 int java_suspend_self(); 1181 1182 void check_and_wait_while_suspended() { 1183 assert(JavaThread::current() == this, "sanity check"); 1184 1185 bool do_self_suspend; 1186 do { 1187 // were we externally suspended while we were waiting? 1188 do_self_suspend = handle_special_suspend_equivalent_condition(); 1189 if (do_self_suspend) { 1190 // don't surprise the thread that suspended us by returning 1191 java_suspend_self(); 1192 set_suspend_equivalent(); 1193 } 1194 } while (do_self_suspend); 1195 } 1196 static void check_safepoint_and_suspend_for_native_trans(JavaThread *thread); 1197 // Check for async exception in addition to safepoint and suspend request. 1198 static void check_special_condition_for_native_trans(JavaThread *thread); 1199 1200 // Same as check_special_condition_for_native_trans but finishes the 1201 // transition into thread_in_Java mode so that it can potentially 1202 // block. 1203 static void check_special_condition_for_native_trans_and_transition(JavaThread *thread); 1204 1205 bool is_ext_suspend_completed(bool called_by_wait, int delay, uint32_t *bits); 1206 bool is_ext_suspend_completed_with_lock(uint32_t *bits) { 1207 MutexLockerEx ml(SR_lock(), Mutex::_no_safepoint_check_flag); 1208 // Warning: is_ext_suspend_completed() may temporarily drop the 1209 // SR_lock to allow the thread to reach a stable thread state if 1210 // it is currently in a transient thread state. 1211 return is_ext_suspend_completed(false /* !called_by_wait */, 1212 SuspendRetryDelay, bits); 1213 } 1214 1215 // We cannot allow wait_for_ext_suspend_completion() to run forever or 1216 // we could hang. SuspendRetryCount and SuspendRetryDelay are normally 1217 // passed as the count and delay parameters. Experiments with specific 1218 // calls to wait_for_ext_suspend_completion() can be done by passing 1219 // other values in the code. Experiments with all calls can be done 1220 // via the appropriate -XX options. 1221 bool wait_for_ext_suspend_completion(int count, int delay, uint32_t *bits); 1222 1223 inline void set_external_suspend(); 1224 inline void clear_external_suspend(); 1225 1226 inline void set_deopt_suspend(); 1227 inline void clear_deopt_suspend(); 1228 bool is_deopt_suspend() { return (_suspend_flags & _deopt_suspend) != 0; } 1229 1230 bool is_external_suspend() const { 1231 return (_suspend_flags & _external_suspend) != 0; 1232 } 1233 // Whenever a thread transitions from native to vm/java it must suspend 1234 // if external|deopt suspend is present. 1235 bool is_suspend_after_native() const { 1236 return (_suspend_flags & (_external_suspend | _deopt_suspend)) != 0; 1237 } 1238 1239 // external suspend request is completed 1240 bool is_ext_suspended() const { 1241 return (_suspend_flags & _ext_suspended) != 0; 1242 } 1243 1244 bool is_external_suspend_with_lock() const { 1245 MutexLockerEx ml(SR_lock(), Mutex::_no_safepoint_check_flag); 1246 return is_external_suspend(); 1247 } 1248 1249 // Special method to handle a pending external suspend request 1250 // when a suspend equivalent condition lifts. 1251 bool handle_special_suspend_equivalent_condition() { 1252 assert(is_suspend_equivalent(), 1253 "should only be called in a suspend equivalence condition"); 1254 MutexLockerEx ml(SR_lock(), Mutex::_no_safepoint_check_flag); 1255 bool ret = is_external_suspend(); 1256 if (!ret) { 1257 // not about to self-suspend so clear suspend equivalence 1258 clear_suspend_equivalent(); 1259 } 1260 // implied else: 1261 // We have a pending external suspend request so we leave the 1262 // suspend_equivalent flag set until java_suspend_self() sets 1263 // the ext_suspended flag and clears the suspend_equivalent 1264 // flag. This insures that wait_for_ext_suspend_completion() 1265 // will return consistent values. 1266 return ret; 1267 } 1268 1269 // utility methods to see if we are doing some kind of suspension 1270 bool is_being_ext_suspended() const { 1271 MutexLockerEx ml(SR_lock(), Mutex::_no_safepoint_check_flag); 1272 return is_ext_suspended() || is_external_suspend(); 1273 } 1274 1275 bool is_suspend_equivalent() const { return _suspend_equivalent; } 1276 1277 void set_suspend_equivalent() { _suspend_equivalent = true; } 1278 void clear_suspend_equivalent() { _suspend_equivalent = false; } 1279 1280 // Thread.stop support 1281 void send_thread_stop(oop throwable); 1282 AsyncRequests clear_special_runtime_exit_condition() { 1283 AsyncRequests x = _special_runtime_exit_condition; 1284 _special_runtime_exit_condition = _no_async_condition; 1285 return x; 1286 } 1287 1288 // Are any async conditions present? 1289 bool has_async_condition() { return (_special_runtime_exit_condition != _no_async_condition); } 1290 1291 void check_and_handle_async_exceptions(bool check_unsafe_error = true); 1292 1293 // these next two are also used for self-suspension and async exception support 1294 void handle_special_runtime_exit_condition(bool check_asyncs = true); 1295 1296 // Return true if JavaThread has an asynchronous condition or 1297 // if external suspension is requested. 1298 bool has_special_runtime_exit_condition() { 1299 // Because we don't use is_external_suspend_with_lock 1300 // it is possible that we won't see an asynchronous external suspend 1301 // request that has just gotten started, i.e., SR_lock grabbed but 1302 // _external_suspend field change either not made yet or not visible 1303 // yet. However, this is okay because the request is asynchronous and 1304 // we will see the new flag value the next time through. It's also 1305 // possible that the external suspend request is dropped after 1306 // we have checked is_external_suspend(), we will recheck its value 1307 // under SR_lock in java_suspend_self(). 1308 return (_special_runtime_exit_condition != _no_async_condition) || 1309 is_external_suspend() || is_deopt_suspend() || is_trace_suspend(); 1310 } 1311 1312 void set_pending_unsafe_access_error() { _special_runtime_exit_condition = _async_unsafe_access_error; } 1313 1314 inline void set_pending_async_exception(oop e); 1315 1316 // Fast-locking support 1317 bool is_lock_owned(address adr) const; 1318 1319 // Accessors for vframe array top 1320 // The linked list of vframe arrays are sorted on sp. This means when we 1321 // unpack the head must contain the vframe array to unpack. 1322 void set_vframe_array_head(vframeArray* value) { _vframe_array_head = value; } 1323 vframeArray* vframe_array_head() const { return _vframe_array_head; } 1324 1325 // Side structure for deferring update of java frame locals until deopt occurs 1326 GrowableArray<jvmtiDeferredLocalVariableSet*>* deferred_locals() const { return _deferred_locals_updates; } 1327 void set_deferred_locals(GrowableArray<jvmtiDeferredLocalVariableSet *>* vf) { _deferred_locals_updates = vf; } 1328 1329 // These only really exist to make debugging deopt problems simpler 1330 1331 void set_vframe_array_last(vframeArray* value) { _vframe_array_last = value; } 1332 vframeArray* vframe_array_last() const { return _vframe_array_last; } 1333 1334 // The special resourceMark used during deoptimization 1335 1336 void set_deopt_mark(DeoptResourceMark* value) { _deopt_mark = value; } 1337 DeoptResourceMark* deopt_mark(void) { return _deopt_mark; } 1338 1339 intptr_t* must_deopt_id() { return _must_deopt_id; } 1340 void set_must_deopt_id(intptr_t* id) { _must_deopt_id = id; } 1341 void clear_must_deopt_id() { _must_deopt_id = NULL; } 1342 1343 void set_deopt_compiled_method(CompiledMethod* nm) { _deopt_nmethod = nm; } 1344 CompiledMethod* deopt_compiled_method() { return _deopt_nmethod; } 1345 1346 Method* callee_target() const { return _callee_target; } 1347 void set_callee_target (Method* x) { _callee_target = x; } 1348 1349 // Oop results of vm runtime calls 1350 oop vm_result() const { return _vm_result; } 1351 void set_vm_result (oop x) { _vm_result = x; } 1352 1353 Metadata* vm_result_2() const { return _vm_result_2; } 1354 void set_vm_result_2 (Metadata* x) { _vm_result_2 = x; } 1355 1356 MemRegion deferred_card_mark() const { return _deferred_card_mark; } 1357 void set_deferred_card_mark(MemRegion mr) { _deferred_card_mark = mr; } 1358 1359 #if INCLUDE_JVMCI 1360 int pending_deoptimization() const { return _pending_deoptimization; } 1361 oop pending_failed_speculation() const { return _pending_failed_speculation; } 1362 bool adjusting_comp_level() const { return _adjusting_comp_level; } 1363 void set_adjusting_comp_level(bool b) { _adjusting_comp_level = b; } 1364 bool has_pending_monitorenter() const { return _pending_monitorenter; } 1365 void set_pending_monitorenter(bool b) { _pending_monitorenter = b; } 1366 void set_pending_deoptimization(int reason) { _pending_deoptimization = reason; } 1367 void set_pending_failed_speculation(oop failed_speculation) { _pending_failed_speculation = failed_speculation; } 1368 void set_pending_transfer_to_interpreter(bool b) { _pending_transfer_to_interpreter = b; } 1369 void set_jvmci_alternate_call_target(address a) { assert(_jvmci._alternate_call_target == NULL, "must be"); _jvmci._alternate_call_target = a; } 1370 void set_jvmci_implicit_exception_pc(address a) { assert(_jvmci._implicit_exception_pc == NULL, "must be"); _jvmci._implicit_exception_pc = a; } 1371 #endif // INCLUDE_JVMCI 1372 1373 // Exception handling for compiled methods 1374 oop exception_oop() const { return _exception_oop; } 1375 address exception_pc() const { return _exception_pc; } 1376 address exception_handler_pc() const { return _exception_handler_pc; } 1377 bool is_method_handle_return() const { return _is_method_handle_return == 1; } 1378 1379 void set_exception_oop(oop o) { (void)const_cast<oop&>(_exception_oop = o); } 1380 void set_exception_pc(address a) { _exception_pc = a; } 1381 void set_exception_handler_pc(address a) { _exception_handler_pc = a; } 1382 void set_is_method_handle_return(bool value) { _is_method_handle_return = value ? 1 : 0; } 1383 1384 void clear_exception_oop_and_pc() { 1385 set_exception_oop(NULL); 1386 set_exception_pc(NULL); 1387 } 1388 1389 // Stack overflow support 1390 // 1391 // (small addresses) 1392 // 1393 // -- <-- stack_end() --- 1394 // | | 1395 // | red pages | 1396 // | | 1397 // -- <-- stack_red_zone_base() | 1398 // | | 1399 // | guard 1400 // | yellow pages zone 1401 // | | 1402 // | | 1403 // -- <-- stack_yellow_zone_base() | 1404 // | | 1405 // | | 1406 // | reserved pages | 1407 // | | 1408 // -- <-- stack_reserved_zone_base() --- --- 1409 // /|\ shadow <-- stack_overflow_limit() (somewhere in here) 1410 // | zone 1411 // \|/ size 1412 // some untouched memory --- 1413 // 1414 // 1415 // -- 1416 // | 1417 // | shadow zone 1418 // | 1419 // -- 1420 // x frame n 1421 // -- 1422 // x frame n-1 1423 // x 1424 // -- 1425 // ... 1426 // 1427 // -- 1428 // x frame 0 1429 // -- <-- stack_base() 1430 // 1431 // (large addresses) 1432 // 1433 1434 private: 1435 // These values are derived from flags StackRedPages, StackYellowPages, 1436 // StackReservedPages and StackShadowPages. The zone size is determined 1437 // ergonomically if page_size > 4K. 1438 static size_t _stack_red_zone_size; 1439 static size_t _stack_yellow_zone_size; 1440 static size_t _stack_reserved_zone_size; 1441 static size_t _stack_shadow_zone_size; 1442 public: 1443 inline size_t stack_available(address cur_sp); 1444 1445 static size_t stack_red_zone_size() { 1446 assert(_stack_red_zone_size > 0, "Don't call this before the field is initialized."); 1447 return _stack_red_zone_size; 1448 } 1449 static void set_stack_red_zone_size(size_t s) { 1450 assert(is_aligned(s, os::vm_page_size()), 1451 "We can not protect if the red zone size is not page aligned."); 1452 assert(_stack_red_zone_size == 0, "This should be called only once."); 1453 _stack_red_zone_size = s; 1454 } 1455 address stack_red_zone_base() { 1456 return (address)(stack_end() + stack_red_zone_size()); 1457 } 1458 bool in_stack_red_zone(address a) { 1459 return a <= stack_red_zone_base() && a >= stack_end(); 1460 } 1461 1462 static size_t stack_yellow_zone_size() { 1463 assert(_stack_yellow_zone_size > 0, "Don't call this before the field is initialized."); 1464 return _stack_yellow_zone_size; 1465 } 1466 static void set_stack_yellow_zone_size(size_t s) { 1467 assert(is_aligned(s, os::vm_page_size()), 1468 "We can not protect if the yellow zone size is not page aligned."); 1469 assert(_stack_yellow_zone_size == 0, "This should be called only once."); 1470 _stack_yellow_zone_size = s; 1471 } 1472 1473 static size_t stack_reserved_zone_size() { 1474 // _stack_reserved_zone_size may be 0. This indicates the feature is off. 1475 return _stack_reserved_zone_size; 1476 } 1477 static void set_stack_reserved_zone_size(size_t s) { 1478 assert(is_aligned(s, os::vm_page_size()), 1479 "We can not protect if the reserved zone size is not page aligned."); 1480 assert(_stack_reserved_zone_size == 0, "This should be called only once."); 1481 _stack_reserved_zone_size = s; 1482 } 1483 address stack_reserved_zone_base() { 1484 return (address)(stack_end() + 1485 (stack_red_zone_size() + stack_yellow_zone_size() + stack_reserved_zone_size())); 1486 } 1487 bool in_stack_reserved_zone(address a) { 1488 return (a <= stack_reserved_zone_base()) && 1489 (a >= (address)((intptr_t)stack_reserved_zone_base() - stack_reserved_zone_size())); 1490 } 1491 1492 static size_t stack_yellow_reserved_zone_size() { 1493 return _stack_yellow_zone_size + _stack_reserved_zone_size; 1494 } 1495 bool in_stack_yellow_reserved_zone(address a) { 1496 return (a <= stack_reserved_zone_base()) && (a >= stack_red_zone_base()); 1497 } 1498 1499 // Size of red + yellow + reserved zones. 1500 static size_t stack_guard_zone_size() { 1501 return stack_red_zone_size() + stack_yellow_reserved_zone_size(); 1502 } 1503 1504 static size_t stack_shadow_zone_size() { 1505 assert(_stack_shadow_zone_size > 0, "Don't call this before the field is initialized."); 1506 return _stack_shadow_zone_size; 1507 } 1508 static void set_stack_shadow_zone_size(size_t s) { 1509 // The shadow area is not allocated or protected, so 1510 // it needs not be page aligned. 1511 // But the stack bang currently assumes that it is a 1512 // multiple of page size. This guarantees that the bang 1513 // loop touches all pages in the shadow zone. 1514 // This can be guaranteed differently, as well. E.g., if 1515 // the page size is a multiple of 4K, banging in 4K steps 1516 // suffices to touch all pages. (Some pages are banged 1517 // several times, though.) 1518 assert(is_aligned(s, os::vm_page_size()), 1519 "Stack bang assumes multiple of page size."); 1520 assert(_stack_shadow_zone_size == 0, "This should be called only once."); 1521 _stack_shadow_zone_size = s; 1522 } 1523 1524 void create_stack_guard_pages(); 1525 void remove_stack_guard_pages(); 1526 1527 void enable_stack_reserved_zone(); 1528 void disable_stack_reserved_zone(); 1529 void enable_stack_yellow_reserved_zone(); 1530 void disable_stack_yellow_reserved_zone(); 1531 void enable_stack_red_zone(); 1532 void disable_stack_red_zone(); 1533 1534 inline bool stack_guard_zone_unused(); 1535 inline bool stack_yellow_reserved_zone_disabled(); 1536 inline bool stack_reserved_zone_disabled(); 1537 inline bool stack_guards_enabled(); 1538 1539 address reserved_stack_activation() const { return _reserved_stack_activation; } 1540 void set_reserved_stack_activation(address addr) { 1541 assert(_reserved_stack_activation == stack_base() 1542 || _reserved_stack_activation == NULL 1543 || addr == stack_base(), "Must not be set twice"); 1544 _reserved_stack_activation = addr; 1545 } 1546 1547 // Attempt to reguard the stack after a stack overflow may have occurred. 1548 // Returns true if (a) guard pages are not needed on this thread, (b) the 1549 // pages are already guarded, or (c) the pages were successfully reguarded. 1550 // Returns false if there is not enough stack space to reguard the pages, in 1551 // which case the caller should unwind a frame and try again. The argument 1552 // should be the caller's (approximate) sp. 1553 bool reguard_stack(address cur_sp); 1554 // Similar to above but see if current stackpoint is out of the guard area 1555 // and reguard if possible. 1556 bool reguard_stack(void); 1557 1558 address stack_overflow_limit() { return _stack_overflow_limit; } 1559 void set_stack_overflow_limit() { 1560 _stack_overflow_limit = 1561 stack_end() + MAX2(JavaThread::stack_guard_zone_size(), JavaThread::stack_shadow_zone_size()); 1562 } 1563 1564 // Misc. accessors/mutators 1565 void set_do_not_unlock(void) { _do_not_unlock_if_synchronized = true; } 1566 void clr_do_not_unlock(void) { _do_not_unlock_if_synchronized = false; } 1567 bool do_not_unlock(void) { return _do_not_unlock_if_synchronized; } 1568 1569 #ifndef PRODUCT 1570 void record_jump(address target, address instr, const char* file, int line); 1571 #endif // PRODUCT 1572 1573 // For assembly stub generation 1574 static ByteSize threadObj_offset() { return byte_offset_of(JavaThread, _threadObj); } 1575 #ifndef PRODUCT 1576 static ByteSize jmp_ring_index_offset() { return byte_offset_of(JavaThread, _jmp_ring_index); } 1577 static ByteSize jmp_ring_offset() { return byte_offset_of(JavaThread, _jmp_ring); } 1578 #endif // PRODUCT 1579 static ByteSize jni_environment_offset() { return byte_offset_of(JavaThread, _jni_environment); } 1580 static ByteSize pending_jni_exception_check_fn_offset() { 1581 return byte_offset_of(JavaThread, _pending_jni_exception_check_fn); 1582 } 1583 static ByteSize last_Java_sp_offset() { 1584 return byte_offset_of(JavaThread, _anchor) + JavaFrameAnchor::last_Java_sp_offset(); 1585 } 1586 static ByteSize last_Java_pc_offset() { 1587 return byte_offset_of(JavaThread, _anchor) + JavaFrameAnchor::last_Java_pc_offset(); 1588 } 1589 static ByteSize frame_anchor_offset() { 1590 return byte_offset_of(JavaThread, _anchor); 1591 } 1592 static ByteSize callee_target_offset() { return byte_offset_of(JavaThread, _callee_target); } 1593 static ByteSize vm_result_offset() { return byte_offset_of(JavaThread, _vm_result); } 1594 static ByteSize vm_result_2_offset() { return byte_offset_of(JavaThread, _vm_result_2); } 1595 static ByteSize thread_state_offset() { return byte_offset_of(JavaThread, _thread_state); } 1596 static ByteSize saved_exception_pc_offset() { return byte_offset_of(JavaThread, _saved_exception_pc); } 1597 static ByteSize osthread_offset() { return byte_offset_of(JavaThread, _osthread); } 1598 #if INCLUDE_JVMCI 1599 static ByteSize pending_deoptimization_offset() { return byte_offset_of(JavaThread, _pending_deoptimization); } 1600 static ByteSize pending_monitorenter_offset() { return byte_offset_of(JavaThread, _pending_monitorenter); } 1601 static ByteSize pending_failed_speculation_offset() { return byte_offset_of(JavaThread, _pending_failed_speculation); } 1602 static ByteSize jvmci_alternate_call_target_offset() { return byte_offset_of(JavaThread, _jvmci._alternate_call_target); } 1603 static ByteSize jvmci_implicit_exception_pc_offset() { return byte_offset_of(JavaThread, _jvmci._implicit_exception_pc); } 1604 static ByteSize jvmci_counters_offset() { return byte_offset_of(JavaThread, _jvmci_counters); } 1605 #endif // INCLUDE_JVMCI 1606 static ByteSize exception_oop_offset() { return byte_offset_of(JavaThread, _exception_oop); } 1607 static ByteSize exception_pc_offset() { return byte_offset_of(JavaThread, _exception_pc); } 1608 static ByteSize exception_handler_pc_offset() { return byte_offset_of(JavaThread, _exception_handler_pc); } 1609 static ByteSize stack_overflow_limit_offset() { return byte_offset_of(JavaThread, _stack_overflow_limit); } 1610 static ByteSize is_method_handle_return_offset() { return byte_offset_of(JavaThread, _is_method_handle_return); } 1611 static ByteSize stack_guard_state_offset() { return byte_offset_of(JavaThread, _stack_guard_state); } 1612 static ByteSize reserved_stack_activation_offset() { return byte_offset_of(JavaThread, _reserved_stack_activation); } 1613 static ByteSize suspend_flags_offset() { return byte_offset_of(JavaThread, _suspend_flags); } 1614 1615 static ByteSize do_not_unlock_if_synchronized_offset() { return byte_offset_of(JavaThread, _do_not_unlock_if_synchronized); } 1616 static ByteSize should_post_on_exceptions_flag_offset() { 1617 return byte_offset_of(JavaThread, _should_post_on_exceptions_flag); 1618 } 1619 1620 #if INCLUDE_ALL_GCS 1621 static ByteSize satb_mark_queue_offset() { return byte_offset_of(JavaThread, _satb_mark_queue); } 1622 static ByteSize dirty_card_queue_offset() { return byte_offset_of(JavaThread, _dirty_card_queue); } 1623 #endif // INCLUDE_ALL_GCS 1624 1625 // Returns the jni environment for this thread 1626 JNIEnv* jni_environment() { return &_jni_environment; } 1627 1628 static JavaThread* thread_from_jni_environment(JNIEnv* env) { 1629 JavaThread *thread_from_jni_env = (JavaThread*)((intptr_t)env - in_bytes(jni_environment_offset())); 1630 // Only return NULL if thread is off the thread list; starting to 1631 // exit should not return NULL. 1632 if (thread_from_jni_env->is_terminated()) { 1633 thread_from_jni_env->block_if_vm_exited(); 1634 return NULL; 1635 } else { 1636 return thread_from_jni_env; 1637 } 1638 } 1639 1640 // JNI critical regions. These can nest. 1641 bool in_critical() { return _jni_active_critical > 0; } 1642 bool in_last_critical() { return _jni_active_critical == 1; } 1643 void enter_critical() { 1644 assert(Thread::current() == this || 1645 (Thread::current()->is_VM_thread() && 1646 SafepointSynchronize::is_synchronizing()), 1647 "this must be current thread or synchronizing"); 1648 _jni_active_critical++; 1649 } 1650 void exit_critical() { 1651 assert(Thread::current() == this, "this must be current thread"); 1652 _jni_active_critical--; 1653 assert(_jni_active_critical >= 0, "JNI critical nesting problem?"); 1654 } 1655 1656 // Checked JNI: is the programmer required to check for exceptions, if so specify 1657 // which function name. Returning to a Java frame should implicitly clear the 1658 // pending check, this is done for Native->Java transitions (i.e. user JNI code). 1659 // VM->Java transistions are not cleared, it is expected that JNI code enclosed 1660 // within ThreadToNativeFromVM makes proper exception checks (i.e. VM internal). 1661 bool is_pending_jni_exception_check() const { return _pending_jni_exception_check_fn != NULL; } 1662 void clear_pending_jni_exception_check() { _pending_jni_exception_check_fn = NULL; } 1663 const char* get_pending_jni_exception_check() const { return _pending_jni_exception_check_fn; } 1664 void set_pending_jni_exception_check(const char* fn_name) { _pending_jni_exception_check_fn = (char*) fn_name; } 1665 1666 // For deadlock detection 1667 int depth_first_number() { return _depth_first_number; } 1668 void set_depth_first_number(int dfn) { _depth_first_number = dfn; } 1669 1670 private: 1671 void set_monitor_chunks(MonitorChunk* monitor_chunks) { _monitor_chunks = monitor_chunks; } 1672 1673 public: 1674 MonitorChunk* monitor_chunks() const { return _monitor_chunks; } 1675 void add_monitor_chunk(MonitorChunk* chunk); 1676 void remove_monitor_chunk(MonitorChunk* chunk); 1677 bool in_deopt_handler() const { return _in_deopt_handler > 0; } 1678 void inc_in_deopt_handler() { _in_deopt_handler++; } 1679 void dec_in_deopt_handler() { 1680 assert(_in_deopt_handler > 0, "mismatched deopt nesting"); 1681 if (_in_deopt_handler > 0) { // robustness 1682 _in_deopt_handler--; 1683 } 1684 } 1685 1686 private: 1687 void set_entry_point(ThreadFunction entry_point) { _entry_point = entry_point; } 1688 1689 public: 1690 1691 // Frame iteration; calls the function f for all frames on the stack 1692 void frames_do(void f(frame*, const RegisterMap*)); 1693 1694 // Memory operations 1695 void oops_do(OopClosure* f, CodeBlobClosure* cf); 1696 1697 // Sweeper operations 1698 virtual void nmethods_do(CodeBlobClosure* cf); 1699 1700 // RedefineClasses Support 1701 void metadata_do(void f(Metadata*)); 1702 1703 // Misc. operations 1704 char* name() const { return (char*)get_thread_name(); } 1705 void print_on(outputStream* st) const; 1706 void print_value(); 1707 void print_thread_state_on(outputStream*) const PRODUCT_RETURN; 1708 void print_thread_state() const PRODUCT_RETURN; 1709 void print_on_error(outputStream* st, char* buf, int buflen) const; 1710 void print_name_on_error(outputStream* st, char* buf, int buflen) const; 1711 void verify(); 1712 const char* get_thread_name() const; 1713 private: 1714 // factor out low-level mechanics for use in both normal and error cases 1715 const char* get_thread_name_string(char* buf = NULL, int buflen = 0) const; 1716 public: 1717 const char* get_threadgroup_name() const; 1718 const char* get_parent_name() const; 1719 1720 // Accessing frames 1721 frame last_frame() { 1722 _anchor.make_walkable(this); 1723 return pd_last_frame(); 1724 } 1725 javaVFrame* last_java_vframe(RegisterMap* reg_map); 1726 1727 // Returns method at 'depth' java or native frames down the stack 1728 // Used for security checks 1729 Klass* security_get_caller_class(int depth); 1730 1731 // Print stack trace in external format 1732 void print_stack_on(outputStream* st); 1733 void print_stack() { print_stack_on(tty); } 1734 1735 // Print stack traces in various internal formats 1736 void trace_stack() PRODUCT_RETURN; 1737 void trace_stack_from(vframe* start_vf) PRODUCT_RETURN; 1738 void trace_frames() PRODUCT_RETURN; 1739 void trace_oops() PRODUCT_RETURN; 1740 1741 // Print an annotated view of the stack frames 1742 void print_frame_layout(int depth = 0, bool validate_only = false) NOT_DEBUG_RETURN; 1743 void validate_frame_layout() { 1744 print_frame_layout(0, true); 1745 } 1746 1747 // Returns the number of stack frames on the stack 1748 int depth() const; 1749 1750 // Function for testing deoptimization 1751 void deoptimize(); 1752 void make_zombies(); 1753 1754 void deoptimized_wrt_marked_nmethods(); 1755 1756 public: 1757 // Returns the running thread as a JavaThread 1758 static inline JavaThread* current(); 1759 1760 // Returns the active Java thread. Do not use this if you know you are calling 1761 // from a JavaThread, as it's slower than JavaThread::current. If called from 1762 // the VMThread, it also returns the JavaThread that instigated the VMThread's 1763 // operation. You may not want that either. 1764 static JavaThread* active(); 1765 1766 inline CompilerThread* as_CompilerThread(); 1767 1768 public: 1769 virtual void run(); 1770 void thread_main_inner(); 1771 1772 private: 1773 // PRIVILEGED STACK 1774 PrivilegedElement* _privileged_stack_top; 1775 GrowableArray<oop>* _array_for_gc; 1776 public: 1777 1778 // Returns the privileged_stack information. 1779 PrivilegedElement* privileged_stack_top() const { return _privileged_stack_top; } 1780 void set_privileged_stack_top(PrivilegedElement *e) { _privileged_stack_top = e; } 1781 void register_array_for_gc(GrowableArray<oop>* array) { _array_for_gc = array; } 1782 1783 public: 1784 // Thread local information maintained by JVMTI. 1785 void set_jvmti_thread_state(JvmtiThreadState *value) { _jvmti_thread_state = value; } 1786 // A JvmtiThreadState is lazily allocated. This jvmti_thread_state() 1787 // getter is used to get this JavaThread's JvmtiThreadState if it has 1788 // one which means NULL can be returned. JvmtiThreadState::state_for() 1789 // is used to get the specified JavaThread's JvmtiThreadState if it has 1790 // one or it allocates a new JvmtiThreadState for the JavaThread and 1791 // returns it. JvmtiThreadState::state_for() will return NULL only if 1792 // the specified JavaThread is exiting. 1793 JvmtiThreadState *jvmti_thread_state() const { return _jvmti_thread_state; } 1794 static ByteSize jvmti_thread_state_offset() { return byte_offset_of(JavaThread, _jvmti_thread_state); } 1795 void set_jvmti_get_loaded_classes_closure(JvmtiGetLoadedClassesClosure* value) { _jvmti_get_loaded_classes_closure = value; } 1796 JvmtiGetLoadedClassesClosure* get_jvmti_get_loaded_classes_closure() const { return _jvmti_get_loaded_classes_closure; } 1797 1798 // JVMTI PopFrame support 1799 // Setting and clearing popframe_condition 1800 // All of these enumerated values are bits. popframe_pending 1801 // indicates that a PopFrame() has been requested and not yet been 1802 // completed. popframe_processing indicates that that PopFrame() is in 1803 // the process of being completed. popframe_force_deopt_reexecution_bit 1804 // indicates that special handling is required when returning to a 1805 // deoptimized caller. 1806 enum PopCondition { 1807 popframe_inactive = 0x00, 1808 popframe_pending_bit = 0x01, 1809 popframe_processing_bit = 0x02, 1810 popframe_force_deopt_reexecution_bit = 0x04 1811 }; 1812 PopCondition popframe_condition() { return (PopCondition) _popframe_condition; } 1813 void set_popframe_condition(PopCondition c) { _popframe_condition = c; } 1814 void set_popframe_condition_bit(PopCondition c) { _popframe_condition |= c; } 1815 void clear_popframe_condition() { _popframe_condition = popframe_inactive; } 1816 static ByteSize popframe_condition_offset() { return byte_offset_of(JavaThread, _popframe_condition); } 1817 bool has_pending_popframe() { return (popframe_condition() & popframe_pending_bit) != 0; } 1818 bool popframe_forcing_deopt_reexecution() { return (popframe_condition() & popframe_force_deopt_reexecution_bit) != 0; } 1819 void clear_popframe_forcing_deopt_reexecution() { _popframe_condition &= ~popframe_force_deopt_reexecution_bit; } 1820 #ifdef CC_INTERP 1821 bool pop_frame_pending(void) { return ((_popframe_condition & popframe_pending_bit) != 0); } 1822 void clr_pop_frame_pending(void) { _popframe_condition = popframe_inactive; } 1823 bool pop_frame_in_process(void) { return ((_popframe_condition & popframe_processing_bit) != 0); } 1824 void set_pop_frame_in_process(void) { _popframe_condition |= popframe_processing_bit; } 1825 void clr_pop_frame_in_process(void) { _popframe_condition &= ~popframe_processing_bit; } 1826 #endif 1827 1828 int frames_to_pop_failed_realloc() const { return _frames_to_pop_failed_realloc; } 1829 void set_frames_to_pop_failed_realloc(int nb) { _frames_to_pop_failed_realloc = nb; } 1830 void dec_frames_to_pop_failed_realloc() { _frames_to_pop_failed_realloc--; } 1831 1832 private: 1833 // Saved incoming arguments to popped frame. 1834 // Used only when popped interpreted frame returns to deoptimized frame. 1835 void* _popframe_preserved_args; 1836 int _popframe_preserved_args_size; 1837 1838 public: 1839 void popframe_preserve_args(ByteSize size_in_bytes, void* start); 1840 void* popframe_preserved_args(); 1841 ByteSize popframe_preserved_args_size(); 1842 WordSize popframe_preserved_args_size_in_words(); 1843 void popframe_free_preserved_args(); 1844 1845 1846 private: 1847 JvmtiThreadState *_jvmti_thread_state; 1848 JvmtiGetLoadedClassesClosure* _jvmti_get_loaded_classes_closure; 1849 1850 // Used by the interpreter in fullspeed mode for frame pop, method 1851 // entry, method exit and single stepping support. This field is 1852 // only set to non-zero by the VM_EnterInterpOnlyMode VM operation. 1853 // It can be set to zero asynchronously (i.e., without a VM operation 1854 // or a lock) so we have to be very careful. 1855 int _interp_only_mode; 1856 1857 public: 1858 // used by the interpreter for fullspeed debugging support (see above) 1859 static ByteSize interp_only_mode_offset() { return byte_offset_of(JavaThread, _interp_only_mode); } 1860 bool is_interp_only_mode() { return (_interp_only_mode != 0); } 1861 int get_interp_only_mode() { return _interp_only_mode; } 1862 void increment_interp_only_mode() { ++_interp_only_mode; } 1863 void decrement_interp_only_mode() { --_interp_only_mode; } 1864 1865 // support for cached flag that indicates whether exceptions need to be posted for this thread 1866 // if this is false, we can avoid deoptimizing when events are thrown 1867 // this gets set to reflect whether jvmtiExport::post_exception_throw would actually do anything 1868 private: 1869 int _should_post_on_exceptions_flag; 1870 1871 public: 1872 int should_post_on_exceptions_flag() { return _should_post_on_exceptions_flag; } 1873 void set_should_post_on_exceptions_flag(int val) { _should_post_on_exceptions_flag = val; } 1874 1875 private: 1876 ThreadStatistics *_thread_stat; 1877 1878 public: 1879 ThreadStatistics* get_thread_stat() const { return _thread_stat; } 1880 1881 // Return a blocker object for which this thread is blocked parking. 1882 oop current_park_blocker(); 1883 1884 private: 1885 static size_t _stack_size_at_create; 1886 1887 public: 1888 static inline size_t stack_size_at_create(void) { 1889 return _stack_size_at_create; 1890 } 1891 static inline void set_stack_size_at_create(size_t value) { 1892 _stack_size_at_create = value; 1893 } 1894 1895 #if INCLUDE_ALL_GCS 1896 // SATB marking queue support 1897 SATBMarkQueue& satb_mark_queue() { return _satb_mark_queue; } 1898 static SATBMarkQueueSet& satb_mark_queue_set() { 1899 return _satb_mark_queue_set; 1900 } 1901 1902 // Dirty card queue support 1903 DirtyCardQueue& dirty_card_queue() { return _dirty_card_queue; } 1904 static DirtyCardQueueSet& dirty_card_queue_set() { 1905 return _dirty_card_queue_set; 1906 } 1907 #endif // INCLUDE_ALL_GCS 1908 1909 // This method initializes the SATB and dirty card queues before a 1910 // JavaThread is added to the Java thread list. Right now, we don't 1911 // have to do anything to the dirty card queue (it should have been 1912 // activated when the thread was created), but we have to activate 1913 // the SATB queue if the thread is created while a marking cycle is 1914 // in progress. The activation / de-activation of the SATB queues at 1915 // the beginning / end of a marking cycle is done during safepoints 1916 // so we have to make sure this method is called outside one to be 1917 // able to safely read the active field of the SATB queue set. Right 1918 // now, it is called just before the thread is added to the Java 1919 // thread list in the Threads::add() method. That method is holding 1920 // the Threads_lock which ensures we are outside a safepoint. We 1921 // cannot do the obvious and set the active field of the SATB queue 1922 // when the thread is created given that, in some cases, safepoints 1923 // might happen between the JavaThread constructor being called and the 1924 // thread being added to the Java thread list (an example of this is 1925 // when the structure for the DestroyJavaVM thread is created). 1926 #if INCLUDE_ALL_GCS 1927 void initialize_queues(); 1928 #else // INCLUDE_ALL_GCS 1929 void initialize_queues() { } 1930 #endif // INCLUDE_ALL_GCS 1931 1932 // Machine dependent stuff 1933 #include OS_CPU_HEADER(thread) 1934 1935 public: 1936 void set_blocked_on_compilation(bool value) { 1937 _blocked_on_compilation = value; 1938 } 1939 1940 bool blocked_on_compilation() { 1941 return _blocked_on_compilation; 1942 } 1943 protected: 1944 bool _blocked_on_compilation; 1945 1946 1947 // JSR166 per-thread parker 1948 private: 1949 Parker* _parker; 1950 public: 1951 Parker* parker() { return _parker; } 1952 1953 // Biased locking support 1954 private: 1955 GrowableArray<MonitorInfo*>* _cached_monitor_info; 1956 public: 1957 GrowableArray<MonitorInfo*>* cached_monitor_info() { return _cached_monitor_info; } 1958 void set_cached_monitor_info(GrowableArray<MonitorInfo*>* info) { _cached_monitor_info = info; } 1959 1960 // clearing/querying jni attach status 1961 bool is_attaching_via_jni() const { return _jni_attach_state == _attaching_via_jni; } 1962 bool has_attached_via_jni() const { return is_attaching_via_jni() || _jni_attach_state == _attached_via_jni; } 1963 inline void set_done_attaching_via_jni(); 1964 }; 1965 1966 // Inline implementation of JavaThread::current 1967 inline JavaThread* JavaThread::current() { 1968 Thread* thread = Thread::current(); 1969 assert(thread->is_Java_thread(), "just checking"); 1970 return (JavaThread*)thread; 1971 } 1972 1973 inline CompilerThread* JavaThread::as_CompilerThread() { 1974 assert(is_Compiler_thread(), "just checking"); 1975 return (CompilerThread*)this; 1976 } 1977 1978 // Dedicated thread to sweep the code cache 1979 class CodeCacheSweeperThread : public JavaThread { 1980 CompiledMethod* _scanned_compiled_method; // nmethod being scanned by the sweeper 1981 public: 1982 CodeCacheSweeperThread(); 1983 // Track the nmethod currently being scanned by the sweeper 1984 void set_scanned_compiled_method(CompiledMethod* cm) { 1985 assert(_scanned_compiled_method == NULL || cm == NULL, "should reset to NULL before writing a new value"); 1986 _scanned_compiled_method = cm; 1987 } 1988 1989 // Hide sweeper thread from external view. 1990 bool is_hidden_from_external_view() const { return true; } 1991 1992 bool is_Code_cache_sweeper_thread() const { return true; } 1993 1994 // Prevent GC from unloading _scanned_compiled_method 1995 void oops_do(OopClosure* f, CodeBlobClosure* cf); 1996 void nmethods_do(CodeBlobClosure* cf); 1997 }; 1998 1999 // A thread used for Compilation. 2000 class CompilerThread : public JavaThread { 2001 friend class VMStructs; 2002 private: 2003 CompilerCounters* _counters; 2004 2005 ciEnv* _env; 2006 CompileLog* _log; 2007 CompileTask* _task; 2008 CompileQueue* _queue; 2009 BufferBlob* _buffer_blob; 2010 2011 AbstractCompiler* _compiler; 2012 2013 public: 2014 2015 static CompilerThread* current(); 2016 2017 CompilerThread(CompileQueue* queue, CompilerCounters* counters); 2018 2019 bool is_Compiler_thread() const { return true; } 2020 2021 virtual bool can_call_java() const; 2022 2023 // Hide native compiler threads from external view. 2024 bool is_hidden_from_external_view() const { return !can_call_java(); } 2025 2026 void set_compiler(AbstractCompiler* c) { _compiler = c; } 2027 AbstractCompiler* compiler() const { return _compiler; } 2028 2029 CompileQueue* queue() const { return _queue; } 2030 CompilerCounters* counters() const { return _counters; } 2031 2032 // Get/set the thread's compilation environment. 2033 ciEnv* env() { return _env; } 2034 void set_env(ciEnv* env) { _env = env; } 2035 2036 BufferBlob* get_buffer_blob() const { return _buffer_blob; } 2037 void set_buffer_blob(BufferBlob* b) { _buffer_blob = b; } 2038 2039 // Get/set the thread's logging information 2040 CompileLog* log() { return _log; } 2041 void init_log(CompileLog* log) { 2042 // Set once, for good. 2043 assert(_log == NULL, "set only once"); 2044 _log = log; 2045 } 2046 2047 #ifndef PRODUCT 2048 private: 2049 IdealGraphPrinter *_ideal_graph_printer; 2050 public: 2051 IdealGraphPrinter *ideal_graph_printer() { return _ideal_graph_printer; } 2052 void set_ideal_graph_printer(IdealGraphPrinter *n) { _ideal_graph_printer = n; } 2053 #endif 2054 2055 // Get/set the thread's current task 2056 CompileTask* task() { return _task; } 2057 void set_task(CompileTask* task) { _task = task; } 2058 }; 2059 2060 inline CompilerThread* CompilerThread::current() { 2061 return JavaThread::current()->as_CompilerThread(); 2062 } 2063 2064 // The active thread queue. It also keeps track of the current used 2065 // thread priorities. 2066 class Threads: AllStatic { 2067 friend class VMStructs; 2068 private: 2069 static JavaThread* _thread_list; 2070 static int _number_of_threads; 2071 static int _number_of_non_daemon_threads; 2072 static int _return_code; 2073 static int _thread_claim_parity; 2074 #ifdef ASSERT 2075 static bool _vm_complete; 2076 #endif 2077 2078 static void initialize_java_lang_classes(JavaThread* main_thread, TRAPS); 2079 static void initialize_jsr292_core_classes(TRAPS); 2080 public: 2081 // Thread management 2082 // force_daemon is a concession to JNI, where we may need to add a 2083 // thread to the thread list before allocating its thread object 2084 static void add(JavaThread* p, bool force_daemon = false); 2085 static void remove(JavaThread* p); 2086 static bool includes(JavaThread* p); 2087 static JavaThread* first() { return _thread_list; } 2088 static void threads_do(ThreadClosure* tc); 2089 static void parallel_java_threads_do(ThreadClosure* tc); 2090 2091 // Initializes the vm and creates the vm thread 2092 static jint create_vm(JavaVMInitArgs* args, bool* canTryAgain); 2093 static void convert_vm_init_libraries_to_agents(); 2094 static void create_vm_init_libraries(); 2095 static void create_vm_init_agents(); 2096 static void shutdown_vm_agents(); 2097 static bool destroy_vm(); 2098 // Supported VM versions via JNI 2099 // Includes JNI_VERSION_1_1 2100 static jboolean is_supported_jni_version_including_1_1(jint version); 2101 // Does not include JNI_VERSION_1_1 2102 static jboolean is_supported_jni_version(jint version); 2103 2104 // The "thread claim parity" provides a way for threads to be claimed 2105 // by parallel worker tasks. 2106 // 2107 // Each thread contains a a "parity" field. A task will claim the 2108 // thread only if its parity field is the same as the global parity, 2109 // which is updated by calling change_thread_claim_parity(). 2110 // 2111 // For this to work change_thread_claim_parity() needs to be called 2112 // exactly once in sequential code before starting parallel tasks 2113 // that should claim threads. 2114 // 2115 // New threads get their parity set to 0 and change_thread_claim_parity() 2116 // never set the global parity to 0. 2117 static int thread_claim_parity() { return _thread_claim_parity; } 2118 static void change_thread_claim_parity(); 2119 static void assert_all_threads_claimed() NOT_DEBUG_RETURN; 2120 2121 // Apply "f->do_oop" to all root oops in all threads. 2122 // This version may only be called by sequential code. 2123 static void oops_do(OopClosure* f, CodeBlobClosure* cf); 2124 // This version may be called by sequential or parallel code. 2125 static void possibly_parallel_oops_do(bool is_par, OopClosure* f, CodeBlobClosure* cf); 2126 // This creates a list of GCTasks, one per thread. 2127 static void create_thread_roots_tasks(GCTaskQueue* q); 2128 // This creates a list of GCTasks, one per thread, for marking objects. 2129 static void create_thread_roots_marking_tasks(GCTaskQueue* q); 2130 2131 // Apply "f->do_oop" to roots in all threads that 2132 // are part of compiled frames 2133 static void compiled_frame_oops_do(OopClosure* f, CodeBlobClosure* cf); 2134 2135 static void convert_hcode_pointers(); 2136 static void restore_hcode_pointers(); 2137 2138 // Sweeper 2139 static void nmethods_do(CodeBlobClosure* cf); 2140 2141 // RedefineClasses support 2142 static void metadata_do(void f(Metadata*)); 2143 static void metadata_handles_do(void f(Metadata*)); 2144 2145 #ifdef ASSERT 2146 static bool is_vm_complete() { return _vm_complete; } 2147 #endif 2148 2149 // Verification 2150 static void verify(); 2151 static void print_on(outputStream* st, bool print_stacks, bool internal_format, bool print_concurrent_locks); 2152 static void print(bool print_stacks, bool internal_format) { 2153 // this function is only used by debug.cpp 2154 print_on(tty, print_stacks, internal_format, false /* no concurrent lock printed */); 2155 } 2156 static void print_on_error(outputStream* st, Thread* current, char* buf, int buflen); 2157 static void print_on_error(Thread* this_thread, outputStream* st, Thread* current, char* buf, 2158 int buflen, bool* found_current); 2159 static void print_threads_compiling(outputStream* st, char* buf, int buflen); 2160 2161 // Get Java threads that are waiting to enter a monitor. If doLock 2162 // is true, then Threads_lock is grabbed as needed. Otherwise, the 2163 // VM needs to be at a safepoint. 2164 static GrowableArray<JavaThread*>* get_pending_threads(int count, 2165 address monitor, bool doLock); 2166 2167 // Get owning Java thread from the monitor's owner field. If doLock 2168 // is true, then Threads_lock is grabbed as needed. Otherwise, the 2169 // VM needs to be at a safepoint. 2170 static JavaThread *owning_thread_from_monitor_owner(address owner, 2171 bool doLock); 2172 2173 // Number of threads on the active threads list 2174 static int number_of_threads() { return _number_of_threads; } 2175 // Number of non-daemon threads on the active threads list 2176 static int number_of_non_daemon_threads() { return _number_of_non_daemon_threads; } 2177 2178 // Deoptimizes all frames tied to marked nmethods 2179 static void deoptimized_wrt_marked_nmethods(); 2180 2181 static JavaThread* find_java_thread_from_java_tid(jlong java_tid); 2182 2183 }; 2184 2185 2186 // Thread iterator 2187 class ThreadClosure: public StackObj { 2188 public: 2189 virtual void do_thread(Thread* thread) = 0; 2190 }; 2191 2192 class SignalHandlerMark: public StackObj { 2193 private: 2194 Thread* _thread; 2195 public: 2196 SignalHandlerMark(Thread* t) { 2197 _thread = t; 2198 if (_thread) _thread->enter_signal_handler(); 2199 } 2200 ~SignalHandlerMark() { 2201 if (_thread) _thread->leave_signal_handler(); 2202 _thread = NULL; 2203 } 2204 }; 2205 2206 2207 #endif // SHARE_VM_RUNTIME_THREAD_HPP