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