1 /* 2 * Copyright (c) 1997, 2021, Oracle and/or its affiliates. All rights reserved. 3 * Copyright (c) 2021, Azul Systems, Inc. All rights reserved. 4 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 5 * 6 * This code is free software; you can redistribute it and/or modify it 7 * under the terms of the GNU General Public License version 2 only, as 8 * published by the Free Software Foundation. 9 * 10 * This code is distributed in the hope that it will be useful, but WITHOUT 11 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 12 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 13 * version 2 for more details (a copy is included in the LICENSE file that 14 * accompanied this code). 15 * 16 * You should have received a copy of the GNU General Public License version 17 * 2 along with this work; if not, write to the Free Software Foundation, 18 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 19 * 20 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 21 * or visit www.oracle.com if you need additional information or have any 22 * questions. 23 * 24 */ 25 26 #ifndef SHARE_RUNTIME_THREAD_HPP 27 #define SHARE_RUNTIME_THREAD_HPP 28 29 #include "jni.h" 30 #include "gc/shared/gcThreadLocalData.hpp" 31 #include "gc/shared/threadLocalAllocBuffer.hpp" 32 #include "memory/allocation.hpp" 33 #include "oops/oop.hpp" 34 #include "oops/oopHandle.hpp" 35 #include "runtime/frame.hpp" 36 #include "runtime/globals.hpp" 37 #include "runtime/handshake.hpp" 38 #include "runtime/javaFrameAnchor.hpp" 39 #include "runtime/mutexLocker.hpp" 40 #include "runtime/os.hpp" 41 #include "runtime/park.hpp" 42 #include "runtime/safepointMechanism.hpp" 43 #include "runtime/stackWatermarkSet.hpp" 44 #include "runtime/stackOverflow.hpp" 45 #include "runtime/threadHeapSampler.hpp" 46 #include "runtime/threadLocalStorage.hpp" 47 #include "runtime/threadStatisticalInfo.hpp" 48 #include "runtime/unhandledOops.hpp" 49 #include "utilities/align.hpp" 50 #include "utilities/exceptions.hpp" 51 #include "utilities/globalDefinitions.hpp" 52 #include "utilities/macros.hpp" 53 #if INCLUDE_JFR 54 #include "jfr/support/jfrThreadExtension.hpp" 55 #endif 56 57 class SafeThreadsListPtr; 58 class ThreadSafepointState; 59 class ThreadsList; 60 class ThreadsSMRSupport; 61 62 class JNIHandleBlock; 63 class JvmtiRawMonitor; 64 class JvmtiSampledObjectAllocEventCollector; 65 class JvmtiThreadState; 66 class JvmtiVMObjectAllocEventCollector; 67 class OSThread; 68 class ThreadStatistics; 69 class ConcurrentLocksDump; 70 class MonitorInfo; 71 72 class vframeArray; 73 class vframe; 74 class javaVFrame; 75 76 class DeoptResourceMark; 77 class JvmtiDeferredUpdates; 78 79 class ThreadClosure; 80 class ICRefillVerifier; 81 82 class Metadata; 83 class ResourceArea; 84 85 class OopStorage; 86 87 DEBUG_ONLY(class ResourceMark;) 88 89 class WorkerThread; 90 91 class JavaThread; 92 93 // Class hierarchy 94 // - Thread 95 // - JavaThread 96 // - various subclasses eg CompilerThread, ServiceThread 97 // - NonJavaThread 98 // - NamedThread 99 // - VMThread 100 // - ConcurrentGCThread 101 // - WorkerThread 102 // - GangWorker 103 // - WatcherThread 104 // - JfrThreadSampler 105 // - LogAsyncWriter 106 // 107 // All Thread subclasses must be either JavaThread or NonJavaThread. 108 // This means !t->is_Java_thread() iff t is a NonJavaThread, or t is 109 // a partially constructed/destroyed Thread. 110 111 // Thread execution sequence and actions: 112 // All threads: 113 // - thread_native_entry // per-OS native entry point 114 // - stack initialization 115 // - other OS-level initialization (signal masks etc) 116 // - handshake with creating thread (if not started suspended) 117 // - this->call_run() // common shared entry point 118 // - shared common initialization 119 // - this->pre_run() // virtual per-thread-type initialization 120 // - this->run() // virtual per-thread-type "main" logic 121 // - shared common tear-down 122 // - this->post_run() // virtual per-thread-type tear-down 123 // - // 'this' no longer referenceable 124 // - OS-level tear-down (minimal) 125 // - final logging 126 // 127 // For JavaThread: 128 // - this->run() // virtual but not normally overridden 129 // - this->thread_main_inner() // extra call level to ensure correct stack calculations 130 // - this->entry_point() // set differently for each kind of JavaThread 131 132 class Thread: public ThreadShadow { 133 friend class VMStructs; 134 friend class JVMCIVMStructs; 135 private: 136 137 #ifndef USE_LIBRARY_BASED_TLS_ONLY 138 // Current thread is maintained as a thread-local variable 139 static THREAD_LOCAL Thread* _thr_current; 140 #endif 141 142 // Thread local data area available to the GC. The internal 143 // structure and contents of this data area is GC-specific. 144 // Only GC and GC barrier code should access this data area. 145 GCThreadLocalData _gc_data; 146 147 public: 148 static ByteSize gc_data_offset() { 149 return byte_offset_of(Thread, _gc_data); 150 } 151 152 template <typename T> T* gc_data() { 153 STATIC_ASSERT(sizeof(T) <= sizeof(_gc_data)); 154 return reinterpret_cast<T*>(&_gc_data); 155 } 156 157 // Exception handling 158 // (Note: _pending_exception and friends are in ThreadShadow) 159 //oop _pending_exception; // pending exception for current thread 160 // const char* _exception_file; // file information for exception (debugging only) 161 // int _exception_line; // line information for exception (debugging only) 162 protected: 163 164 DEBUG_ONLY(static Thread* _starting_thread;) 165 166 // Support for forcing alignment of thread objects for biased locking 167 void* _real_malloc_address; 168 169 // JavaThread lifecycle support: 170 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 171 friend class ScanHazardPtrGatherProtectedThreadsClosure; // for cmpxchg_threads_hazard_ptr(), get_threads_hazard_ptr(), is_hazard_ptr_tagged() access 172 friend class ScanHazardPtrGatherThreadsListClosure; // for get_threads_hazard_ptr(), untag_hazard_ptr() access 173 friend class ScanHazardPtrPrintMatchingThreadsClosure; // for get_threads_hazard_ptr(), is_hazard_ptr_tagged() access 174 friend class ThreadsSMRSupport; // for _nested_threads_hazard_ptr_cnt, _threads_hazard_ptr, _threads_list_ptr access 175 friend class ThreadsListHandleTest; // for _nested_threads_hazard_ptr_cnt, _threads_hazard_ptr, _threads_list_ptr access 176 friend class ValidateHazardPtrsClosure; // for get_threads_hazard_ptr(), untag_hazard_ptr() access 177 178 ThreadsList* volatile _threads_hazard_ptr; 179 SafeThreadsListPtr* _threads_list_ptr; 180 ThreadsList* cmpxchg_threads_hazard_ptr(ThreadsList* exchange_value, ThreadsList* compare_value); 181 ThreadsList* get_threads_hazard_ptr() const; 182 void set_threads_hazard_ptr(ThreadsList* new_list); 183 static bool is_hazard_ptr_tagged(ThreadsList* list) { 184 return (intptr_t(list) & intptr_t(1)) == intptr_t(1); 185 } 186 static ThreadsList* tag_hazard_ptr(ThreadsList* list) { 187 return (ThreadsList*)(intptr_t(list) | intptr_t(1)); 188 } 189 static ThreadsList* untag_hazard_ptr(ThreadsList* list) { 190 return (ThreadsList*)(intptr_t(list) & ~intptr_t(1)); 191 } 192 // This field is enabled via -XX:+EnableThreadSMRStatistics: 193 uint _nested_threads_hazard_ptr_cnt; 194 void dec_nested_threads_hazard_ptr_cnt() { 195 assert(_nested_threads_hazard_ptr_cnt != 0, "mismatched {dec,inc}_nested_threads_hazard_ptr_cnt()"); 196 _nested_threads_hazard_ptr_cnt--; 197 } 198 void inc_nested_threads_hazard_ptr_cnt() { 199 _nested_threads_hazard_ptr_cnt++; 200 } 201 uint nested_threads_hazard_ptr_cnt() { 202 return _nested_threads_hazard_ptr_cnt; 203 } 204 205 public: 206 // Is the target JavaThread protected by the calling Thread 207 // or by some other mechanism: 208 static bool is_JavaThread_protected(const JavaThread* p); 209 210 void* operator new(size_t size) throw() { return allocate(size, true); } 211 void* operator new(size_t size, const std::nothrow_t& nothrow_constant) throw() { 212 return allocate(size, false); } 213 void operator delete(void* p); 214 215 protected: 216 static void* allocate(size_t size, bool throw_excpt, MEMFLAGS flags = mtThread); 217 218 private: 219 DEBUG_ONLY(bool _suspendible_thread;) 220 221 public: 222 // Determines if a heap allocation failure will be retried 223 // (e.g., by deoptimizing and re-executing in the interpreter). 224 // In this case, the failed allocation must raise 225 // Universe::out_of_memory_error_retry() and omit side effects 226 // such as JVMTI events and handling -XX:+HeapDumpOnOutOfMemoryError 227 // and -XX:OnOutOfMemoryError. 228 virtual bool in_retryable_allocation() const { return false; } 229 230 #ifdef ASSERT 231 void set_suspendible_thread() { 232 _suspendible_thread = true; 233 } 234 235 void clear_suspendible_thread() { 236 _suspendible_thread = false; 237 } 238 239 bool is_suspendible_thread() { return _suspendible_thread; } 240 #endif 241 242 private: 243 // Active_handles points to a block of handles 244 JNIHandleBlock* _active_handles; 245 246 // One-element thread local free list 247 JNIHandleBlock* _free_handle_block; 248 249 // Point to the last handle mark 250 HandleMark* _last_handle_mark; 251 252 // Claim value for parallel iteration over threads. 253 uintx _threads_do_token; 254 255 // Support for GlobalCounter 256 private: 257 volatile uintx _rcu_counter; 258 public: 259 volatile uintx* get_rcu_counter() { 260 return &_rcu_counter; 261 } 262 263 public: 264 void set_last_handle_mark(HandleMark* mark) { _last_handle_mark = mark; } 265 HandleMark* last_handle_mark() const { return _last_handle_mark; } 266 private: 267 268 #ifdef ASSERT 269 ICRefillVerifier* _missed_ic_stub_refill_verifier; 270 271 public: 272 ICRefillVerifier* missed_ic_stub_refill_verifier() { 273 return _missed_ic_stub_refill_verifier; 274 } 275 276 void set_missed_ic_stub_refill_verifier(ICRefillVerifier* verifier) { 277 _missed_ic_stub_refill_verifier = verifier; 278 } 279 #endif // ASSERT 280 281 private: 282 // Used by SkipGCALot class. 283 NOT_PRODUCT(bool _skip_gcalot;) // Should we elide gc-a-lot? 284 285 friend class GCLocker; 286 287 private: 288 ThreadLocalAllocBuffer _tlab; // Thread-local eden 289 jlong _allocated_bytes; // Cumulative number of bytes allocated on 290 // the Java heap 291 ThreadHeapSampler _heap_sampler; // For use when sampling the memory. 292 293 ThreadStatisticalInfo _statistical_info; // Statistics about the thread 294 295 JFR_ONLY(DEFINE_THREAD_LOCAL_FIELD_JFR;) // Thread-local data for jfr 296 297 JvmtiRawMonitor* _current_pending_raw_monitor; // JvmtiRawMonitor this thread 298 // is waiting to lock 299 public: 300 // Constructor 301 Thread(); 302 virtual ~Thread() = 0; // Thread is abstract. 303 304 // Manage Thread::current() 305 void initialize_thread_current(); 306 static void clear_thread_current(); // TLS cleanup needed before threads terminate 307 308 protected: 309 // To be implemented by children. 310 virtual void run() = 0; 311 virtual void pre_run() = 0; 312 virtual void post_run() = 0; // Note: Thread must not be deleted prior to calling this! 313 314 #ifdef ASSERT 315 enum RunState { 316 PRE_CALL_RUN, 317 CALL_RUN, 318 PRE_RUN, 319 RUN, 320 POST_RUN 321 // POST_CALL_RUN - can't define this one as 'this' may be deleted when we want to set it 322 }; 323 RunState _run_state; // for lifecycle checks 324 #endif 325 326 327 public: 328 // invokes <ChildThreadClass>::run(), with common preparations and cleanups. 329 void call_run(); 330 331 // Testers 332 virtual bool is_VM_thread() const { return false; } 333 virtual bool is_Java_thread() const { return false; } 334 virtual bool is_Compiler_thread() const { return false; } 335 virtual bool is_Code_cache_sweeper_thread() const { return false; } 336 virtual bool is_service_thread() const { return false; } 337 virtual bool is_monitor_deflation_thread() const { return false; } 338 virtual bool is_hidden_from_external_view() const { return false; } 339 virtual bool is_jvmti_agent_thread() const { return false; } 340 // True iff the thread can perform GC operations at a safepoint. 341 // Generally will be true only of VM thread and parallel GC WorkGang 342 // threads. 343 virtual bool is_GC_task_thread() const { return false; } 344 virtual bool is_Watcher_thread() const { return false; } 345 virtual bool is_ConcurrentGC_thread() const { return false; } 346 virtual bool is_Named_thread() const { return false; } 347 virtual bool is_Worker_thread() const { return false; } 348 virtual bool is_JfrSampler_thread() const { return false; } 349 350 // Can this thread make Java upcalls 351 virtual bool can_call_java() const { return false; } 352 353 // Is this a JavaThread that is on the VM's current ThreadsList? 354 // If so it must participate in the safepoint protocol. 355 virtual bool is_active_Java_thread() const { return false; } 356 357 // Casts 358 inline JavaThread* as_Java_thread(); 359 inline const JavaThread* as_Java_thread() const; 360 361 virtual char* name() const { return (char*)"Unknown thread"; } 362 363 // Returns the current thread (ASSERTS if NULL) 364 static inline Thread* current(); 365 // Returns the current thread, or NULL if not attached 366 static inline Thread* current_or_null(); 367 // Returns the current thread, or NULL if not attached, and is 368 // safe for use from signal-handlers 369 static inline Thread* current_or_null_safe(); 370 371 // Common thread operations 372 #ifdef ASSERT 373 static void check_for_dangling_thread_pointer(Thread *thread); 374 #endif 375 static void set_priority(Thread* thread, ThreadPriority priority); 376 static ThreadPriority get_priority(const Thread* const thread); 377 static void start(Thread* thread); 378 379 void set_native_thread_name(const char *name) { 380 assert(Thread::current() == this, "set_native_thread_name can only be called on the current thread"); 381 os::set_native_thread_name(name); 382 } 383 384 // Support for Unhandled Oop detection 385 // Add the field for both, fastdebug and debug, builds to keep 386 // Thread's fields layout the same. 387 // Note: CHECK_UNHANDLED_OOPS is defined only for fastdebug build. 388 #ifdef CHECK_UNHANDLED_OOPS 389 private: 390 UnhandledOops* _unhandled_oops; 391 #elif defined(ASSERT) 392 private: 393 void* _unhandled_oops; 394 #endif 395 #ifdef CHECK_UNHANDLED_OOPS 396 public: 397 UnhandledOops* unhandled_oops() { return _unhandled_oops; } 398 // Mark oop safe for gc. It may be stack allocated but won't move. 399 void allow_unhandled_oop(oop *op) { 400 if (CheckUnhandledOops) unhandled_oops()->allow_unhandled_oop(op); 401 } 402 // Clear oops at safepoint so crashes point to unhandled oop violator 403 void clear_unhandled_oops() { 404 if (CheckUnhandledOops) unhandled_oops()->clear_unhandled_oops(); 405 } 406 #endif // CHECK_UNHANDLED_OOPS 407 408 public: 409 #ifndef PRODUCT 410 bool skip_gcalot() { return _skip_gcalot; } 411 void set_skip_gcalot(bool v) { _skip_gcalot = v; } 412 #endif 413 414 // Resource area 415 ResourceArea* resource_area() const { return _resource_area; } 416 void set_resource_area(ResourceArea* area) { _resource_area = area; } 417 418 OSThread* osthread() const { return _osthread; } 419 void set_osthread(OSThread* thread) { _osthread = thread; } 420 421 // JNI handle support 422 JNIHandleBlock* active_handles() const { return _active_handles; } 423 void set_active_handles(JNIHandleBlock* block) { _active_handles = block; } 424 JNIHandleBlock* free_handle_block() const { return _free_handle_block; } 425 void set_free_handle_block(JNIHandleBlock* block) { _free_handle_block = block; } 426 427 // Internal handle support 428 HandleArea* handle_area() const { return _handle_area; } 429 void set_handle_area(HandleArea* area) { _handle_area = area; } 430 431 GrowableArray<Metadata*>* metadata_handles() const { return _metadata_handles; } 432 void set_metadata_handles(GrowableArray<Metadata*>* handles){ _metadata_handles = handles; } 433 434 // Thread-Local Allocation Buffer (TLAB) support 435 ThreadLocalAllocBuffer& tlab() { return _tlab; } 436 void initialize_tlab(); 437 438 jlong allocated_bytes() { return _allocated_bytes; } 439 void set_allocated_bytes(jlong value) { _allocated_bytes = value; } 440 void incr_allocated_bytes(jlong size) { _allocated_bytes += size; } 441 inline jlong cooked_allocated_bytes(); 442 443 ThreadHeapSampler& heap_sampler() { return _heap_sampler; } 444 445 ThreadStatisticalInfo& statistical_info() { return _statistical_info; } 446 447 JFR_ONLY(DEFINE_THREAD_LOCAL_ACCESSOR_JFR;) 448 449 // For tracking the Jvmti raw monitor the thread is pending on. 450 JvmtiRawMonitor* current_pending_raw_monitor() { 451 return _current_pending_raw_monitor; 452 } 453 void set_current_pending_raw_monitor(JvmtiRawMonitor* monitor) { 454 _current_pending_raw_monitor = monitor; 455 } 456 457 // GC support 458 // Apply "f->do_oop" to all root oops in "this". 459 // Used by JavaThread::oops_do. 460 // Apply "cf->do_code_blob" (if !NULL) to all code blobs active in frames 461 virtual void oops_do_no_frames(OopClosure* f, CodeBlobClosure* cf); 462 virtual void oops_do_frames(OopClosure* f, CodeBlobClosure* cf) {} 463 void oops_do(OopClosure* f, CodeBlobClosure* cf); 464 465 // Handles the parallel case for claim_threads_do. 466 private: 467 bool claim_par_threads_do(uintx claim_token); 468 public: 469 // Requires that "claim_token" is that of the current iteration. 470 // If "is_par" is false, sets the token of "this" to 471 // "claim_token", and returns "true". If "is_par" is true, 472 // uses an atomic instruction to set the current thread's token to 473 // "claim_token", if it is not already. Returns "true" iff the 474 // calling thread does the update, this indicates that the calling thread 475 // has claimed the thread in the current iteration. 476 bool claim_threads_do(bool is_par, uintx claim_token) { 477 if (!is_par) { 478 _threads_do_token = claim_token; 479 return true; 480 } else { 481 return claim_par_threads_do(claim_token); 482 } 483 } 484 485 uintx threads_do_token() const { return _threads_do_token; } 486 487 // jvmtiRedefineClasses support 488 void metadata_handles_do(void f(Metadata*)); 489 490 private: 491 // Check if address is within the given range of this thread's 492 // stack: stack_base() > adr >/>= limit 493 // The check is inclusive of limit if passed true, else exclusive. 494 bool is_in_stack_range(address adr, address limit, bool inclusive) const { 495 assert(stack_base() > limit && limit >= stack_end(), "limit is outside of stack"); 496 return stack_base() > adr && (inclusive ? adr >= limit : adr > limit); 497 } 498 499 public: 500 // Used by fast lock support 501 virtual bool is_lock_owned(address adr) const; 502 503 // Check if address is within the given range of this thread's 504 // stack: stack_base() > adr >= limit 505 bool is_in_stack_range_incl(address adr, address limit) const { 506 return is_in_stack_range(adr, limit, true); 507 } 508 509 // Check if address is within the given range of this thread's 510 // stack: stack_base() > adr > limit 511 bool is_in_stack_range_excl(address adr, address limit) const { 512 return is_in_stack_range(adr, limit, false); 513 } 514 515 // Check if address is in the stack mapped to this thread. Used mainly in 516 // error reporting (so has to include guard zone) and frame printing. 517 // Expects _stack_base to be initialized - checked with assert. 518 bool is_in_full_stack_checked(address adr) const { 519 return is_in_stack_range_incl(adr, stack_end()); 520 } 521 522 // Like is_in_full_stack_checked but without the assertions as this 523 // may be called in a thread before _stack_base is initialized. 524 bool is_in_full_stack(address adr) const { 525 address stack_end = _stack_base - _stack_size; 526 return _stack_base > adr && adr >= stack_end; 527 } 528 529 // Check if address is in the live stack of this thread (not just for locks). 530 // Warning: can only be called by the current thread on itself. 531 bool is_in_live_stack(address adr) const { 532 assert(Thread::current() == this, "is_in_live_stack can only be called from current thread"); 533 return is_in_stack_range_incl(adr, os::current_stack_pointer()); 534 } 535 536 // Sets this thread as starting thread. Returns failure if thread 537 // creation fails due to lack of memory, too many threads etc. 538 bool set_as_starting_thread(); 539 540 protected: 541 // OS data associated with the thread 542 OSThread* _osthread; // Platform-specific thread information 543 544 // Thread local resource area for temporary allocation within the VM 545 ResourceArea* _resource_area; 546 547 DEBUG_ONLY(ResourceMark* _current_resource_mark;) 548 549 // Thread local handle area for allocation of handles within the VM 550 HandleArea* _handle_area; 551 GrowableArray<Metadata*>* _metadata_handles; 552 553 // Support for stack overflow handling, get_thread, etc. 554 address _stack_base; 555 size_t _stack_size; 556 int _lgrp_id; 557 558 public: 559 // Stack overflow support 560 address stack_base() const { assert(_stack_base != NULL,"Sanity check"); return _stack_base; } 561 void set_stack_base(address base) { _stack_base = base; } 562 size_t stack_size() const { return _stack_size; } 563 void set_stack_size(size_t size) { _stack_size = size; } 564 address stack_end() const { return stack_base() - stack_size(); } 565 void record_stack_base_and_size(); 566 void register_thread_stack_with_NMT() NOT_NMT_RETURN; 567 void unregister_thread_stack_with_NMT() NOT_NMT_RETURN; 568 569 int lgrp_id() const { return _lgrp_id; } 570 void set_lgrp_id(int value) { _lgrp_id = value; } 571 572 // Printing 573 void print_on(outputStream* st, bool print_extended_info) const; 574 virtual void print_on(outputStream* st) const { print_on(st, false); } 575 void print() const; 576 virtual void print_on_error(outputStream* st, char* buf, int buflen) const; 577 void print_value_on(outputStream* st) const; 578 579 // Debug-only code 580 #ifdef ASSERT 581 private: 582 // Deadlock detection support for Mutex locks. List of locks own by thread. 583 Mutex* _owned_locks; 584 // Mutex::set_owner_implementation is the only place where _owned_locks is modified, 585 // thus the friendship 586 friend class Mutex; 587 friend class Monitor; 588 589 public: 590 void print_owned_locks_on(outputStream* st) const; 591 void print_owned_locks() const { print_owned_locks_on(tty); } 592 Mutex* owned_locks() const { return _owned_locks; } 593 bool owns_locks() const { return owned_locks() != NULL; } 594 595 // Deadlock detection 596 ResourceMark* current_resource_mark() { return _current_resource_mark; } 597 void set_current_resource_mark(ResourceMark* rm) { _current_resource_mark = rm; } 598 #endif // ASSERT 599 600 private: 601 volatile int _jvmti_env_iteration_count; 602 603 public: 604 void entering_jvmti_env_iteration() { ++_jvmti_env_iteration_count; } 605 void leaving_jvmti_env_iteration() { --_jvmti_env_iteration_count; } 606 bool is_inside_jvmti_env_iteration() { return _jvmti_env_iteration_count > 0; } 607 608 // Code generation 609 static ByteSize exception_file_offset() { return byte_offset_of(Thread, _exception_file); } 610 static ByteSize exception_line_offset() { return byte_offset_of(Thread, _exception_line); } 611 static ByteSize active_handles_offset() { return byte_offset_of(Thread, _active_handles); } 612 613 static ByteSize stack_base_offset() { return byte_offset_of(Thread, _stack_base); } 614 static ByteSize stack_size_offset() { return byte_offset_of(Thread, _stack_size); } 615 616 static ByteSize tlab_start_offset() { return byte_offset_of(Thread, _tlab) + ThreadLocalAllocBuffer::start_offset(); } 617 static ByteSize tlab_end_offset() { return byte_offset_of(Thread, _tlab) + ThreadLocalAllocBuffer::end_offset(); } 618 static ByteSize tlab_top_offset() { return byte_offset_of(Thread, _tlab) + ThreadLocalAllocBuffer::top_offset(); } 619 static ByteSize tlab_pf_top_offset() { return byte_offset_of(Thread, _tlab) + ThreadLocalAllocBuffer::pf_top_offset(); } 620 621 static ByteSize allocated_bytes_offset() { return byte_offset_of(Thread, _allocated_bytes); } 622 623 JFR_ONLY(DEFINE_THREAD_LOCAL_OFFSET_JFR;) 624 625 public: 626 ParkEvent * volatile _ParkEvent; // for Object monitors, JVMTI raw monitors, 627 // and ObjectSynchronizer::read_stable_mark 628 629 // Termination indicator used by the signal handler. 630 // _ParkEvent is just a convenient field we can NULL out after setting the JavaThread termination state 631 // (which can't itself be read from the signal handler if a signal hits during the Thread destructor). 632 bool has_terminated() { return Atomic::load(&_ParkEvent) == NULL; }; 633 634 jint _hashStateW; // Marsaglia Shift-XOR thread-local RNG 635 jint _hashStateX; // thread-specific hashCode generator state 636 jint _hashStateY; 637 jint _hashStateZ; 638 639 // Low-level leaf-lock primitives used to implement synchronization. 640 // Not for general synchronization use. 641 static void SpinAcquire(volatile int * Lock, const char * Name); 642 static void SpinRelease(volatile int * Lock); 643 644 #if defined(__APPLE__) && defined(AARCH64) 645 private: 646 DEBUG_ONLY(bool _wx_init); 647 WXMode _wx_state; 648 public: 649 void init_wx(); 650 WXMode enable_wx(WXMode new_state); 651 652 void assert_wx_state(WXMode expected) { 653 assert(_wx_state == expected, "wrong state"); 654 } 655 #endif // __APPLE__ && AARCH64 656 657 private: 658 bool _in_asgct = false; 659 public: 660 bool in_asgct() const { return _in_asgct; } 661 void set_in_asgct(bool value) { _in_asgct = value; } 662 static bool current_in_asgct() { 663 Thread *cur = Thread::current_or_null_safe(); 664 return cur != nullptr && cur->in_asgct(); 665 } 666 }; 667 668 class ThreadInAsgct { 669 private: 670 Thread* _thread; 671 public: 672 ThreadInAsgct(Thread* thread) : _thread(thread) { 673 assert(thread != nullptr, "invariant"); 674 assert(!thread->in_asgct(), "invariant"); 675 thread->set_in_asgct(true); 676 } 677 ~ThreadInAsgct() { 678 assert(_thread->in_asgct(), "invariant"); 679 _thread->set_in_asgct(false); 680 } 681 }; 682 683 // Inline implementation of Thread::current() 684 inline Thread* Thread::current() { 685 Thread* current = current_or_null(); 686 assert(current != NULL, "Thread::current() called on detached thread"); 687 return current; 688 } 689 690 inline Thread* Thread::current_or_null() { 691 #ifndef USE_LIBRARY_BASED_TLS_ONLY 692 return _thr_current; 693 #else 694 if (ThreadLocalStorage::is_initialized()) { 695 return ThreadLocalStorage::thread(); 696 } 697 return NULL; 698 #endif 699 } 700 701 inline Thread* Thread::current_or_null_safe() { 702 if (ThreadLocalStorage::is_initialized()) { 703 return ThreadLocalStorage::thread(); 704 } 705 return NULL; 706 } 707 708 class CompilerThread; 709 710 typedef void (*ThreadFunction)(JavaThread*, TRAPS); 711 712 class JavaThread: public Thread { 713 friend class VMStructs; 714 friend class JVMCIVMStructs; 715 friend class WhiteBox; 716 friend class ThreadsSMRSupport; // to access _threadObj for exiting_threads_oops_do 717 friend class HandshakeState; 718 private: 719 bool _in_asgct; // Is set when this JavaThread is handling ASGCT call 720 bool _on_thread_list; // Is set when this JavaThread is added to the Threads list 721 OopHandle _threadObj; // The Java level thread object 722 723 #ifdef ASSERT 724 private: 725 int _java_call_counter; 726 727 public: 728 int java_call_counter() { return _java_call_counter; } 729 void inc_java_call_counter() { _java_call_counter++; } 730 void dec_java_call_counter() { 731 assert(_java_call_counter > 0, "Invalid nesting of JavaCallWrapper"); 732 _java_call_counter--; 733 } 734 private: // restore original namespace restriction 735 #endif // ifdef ASSERT 736 737 JavaFrameAnchor _anchor; // Encapsulation of current java frame and it state 738 739 ThreadFunction _entry_point; 740 741 JNIEnv _jni_environment; 742 743 // Deopt support 744 DeoptResourceMark* _deopt_mark; // Holds special ResourceMark for deoptimization 745 746 CompiledMethod* _deopt_nmethod; // CompiledMethod that is currently being deoptimized 747 vframeArray* _vframe_array_head; // Holds the heap of the active vframeArrays 748 vframeArray* _vframe_array_last; // Holds last vFrameArray we popped 749 // Holds updates by JVMTI agents for compiled frames that cannot be performed immediately. They 750 // will be carried out as soon as possible which, in most cases, is just before deoptimization of 751 // the frame, when control returns to it. 752 JvmtiDeferredUpdates* _jvmti_deferred_updates; 753 754 // Handshake value for fixing 6243940. We need a place for the i2c 755 // adapter to store the callee Method*. This value is NEVER live 756 // across a gc point so it does NOT have to be gc'd 757 // The handshake is open ended since we can't be certain that it will 758 // be NULLed. This is because we rarely ever see the race and end up 759 // in handle_wrong_method which is the backend of the handshake. See 760 // code in i2c adapters and handle_wrong_method. 761 762 Method* _callee_target; 763 764 // Used to pass back results to the interpreter or generated code running Java code. 765 oop _vm_result; // oop result is GC-preserved 766 Metadata* _vm_result_2; // non-oop result 767 768 // See ReduceInitialCardMarks: this holds the precise space interval of 769 // the most recent slow path allocation for which compiled code has 770 // elided card-marks for performance along the fast-path. 771 MemRegion _deferred_card_mark; 772 773 ObjectMonitor* volatile _current_pending_monitor; // ObjectMonitor this thread is waiting to lock 774 bool _current_pending_monitor_is_from_java; // locking is from Java code 775 ObjectMonitor* volatile _current_waiting_monitor; // ObjectMonitor on which this thread called Object.wait() 776 public: 777 volatile intptr_t _Stalled; 778 779 // For tracking the heavyweight monitor the thread is pending on. 780 ObjectMonitor* current_pending_monitor() { 781 // Use Atomic::load() to prevent data race between concurrent modification and 782 // concurrent readers, e.g. ThreadService::get_current_contended_monitor(). 783 // Especially, reloading pointer from thread after NULL check must be prevented. 784 return Atomic::load(&_current_pending_monitor); 785 } 786 void set_current_pending_monitor(ObjectMonitor* monitor) { 787 Atomic::store(&_current_pending_monitor, monitor); 788 } 789 void set_current_pending_monitor_is_from_java(bool from_java) { 790 _current_pending_monitor_is_from_java = from_java; 791 } 792 bool current_pending_monitor_is_from_java() { 793 return _current_pending_monitor_is_from_java; 794 } 795 ObjectMonitor* current_waiting_monitor() { 796 // See the comment in current_pending_monitor() above. 797 return Atomic::load(&_current_waiting_monitor); 798 } 799 void set_current_waiting_monitor(ObjectMonitor* monitor) { 800 Atomic::store(&_current_waiting_monitor, monitor); 801 } 802 803 private: 804 MonitorChunk* _monitor_chunks; // Contains the off stack monitors 805 // allocated during deoptimization 806 // and by JNI_MonitorEnter/Exit 807 808 enum SuspendFlags { 809 // NOTE: avoid using the sign-bit as cc generates different test code 810 // when the sign-bit is used, and sometimes incorrectly - see CR 6398077 811 _has_async_exception = 0x00000001U, // there is a pending async exception 812 _trace_flag = 0x00000004U, // call tracing backend 813 _obj_deopt = 0x00000008U // suspend for object reallocation and relocking for JVMTI agent 814 }; 815 816 // various suspension related flags - atomically updated 817 // overloaded with async exceptions so that we do a single check when transitioning from native->Java 818 volatile uint32_t _suspend_flags; 819 820 inline void set_suspend_flag(SuspendFlags f); 821 inline void clear_suspend_flag(SuspendFlags f); 822 823 public: 824 inline void set_trace_flag(); 825 inline void clear_trace_flag(); 826 inline void set_obj_deopt_flag(); 827 inline void clear_obj_deopt_flag(); 828 bool is_trace_suspend() { return (_suspend_flags & _trace_flag) != 0; } 829 bool is_obj_deopt_suspend() { return (_suspend_flags & _obj_deopt) != 0; } 830 831 // Asynchronous exceptions support 832 private: 833 enum AsyncExceptionCondition { 834 _no_async_condition = 0, 835 _async_exception, 836 _async_unsafe_access_error 837 }; 838 AsyncExceptionCondition _async_exception_condition; 839 oop _pending_async_exception; 840 841 void set_async_exception_condition(AsyncExceptionCondition aec) { _async_exception_condition = aec; } 842 AsyncExceptionCondition clear_async_exception_condition() { 843 AsyncExceptionCondition x = _async_exception_condition; 844 _async_exception_condition = _no_async_condition; 845 return x; 846 } 847 848 public: 849 bool has_async_exception_condition(bool check_unsafe_access_error = true) { 850 return check_unsafe_access_error ? _async_exception_condition != _no_async_condition 851 : _async_exception_condition == _async_exception; 852 } 853 inline void set_pending_async_exception(oop e); 854 void set_pending_unsafe_access_error() { 855 // Don't overwrite an asynchronous exception sent by another thread 856 if (_async_exception_condition == _no_async_condition) { 857 set_async_exception_condition(_async_unsafe_access_error); 858 } 859 } 860 void check_and_handle_async_exceptions(); 861 // Installs a pending exception to be inserted later 862 static void send_async_exception(oop thread_oop, oop java_throwable); 863 void send_thread_stop(oop throwable); 864 865 // Safepoint support 866 public: // Expose _thread_state for SafeFetchInt() 867 volatile JavaThreadState _thread_state; 868 private: 869 SafepointMechanism::ThreadData _poll_data; 870 ThreadSafepointState* _safepoint_state; // Holds information about a thread during a safepoint 871 address _saved_exception_pc; // Saved pc of instruction where last implicit exception happened 872 NOT_PRODUCT(bool _requires_cross_modify_fence;) // State used by VerifyCrossModifyFence 873 #ifdef ASSERT 874 // Debug support for checking if code allows safepoints or not. 875 // Safepoints in the VM can happen because of allocation, invoking a VM operation, or blocking on 876 // mutex, or blocking on an object synchronizer (Java locking). 877 // If _no_safepoint_count is non-zero, then an assertion failure will happen in any of 878 // the above cases. The class NoSafepointVerifier is used to set this counter. 879 int _no_safepoint_count; // If 0, thread allow a safepoint to happen 880 881 public: 882 void inc_no_safepoint_count() { _no_safepoint_count++; } 883 void dec_no_safepoint_count() { _no_safepoint_count--; } 884 #endif // ASSERT 885 public: 886 // These functions check conditions before possibly going to a safepoint. 887 // including NoSafepointVerifier. 888 void check_for_valid_safepoint_state() NOT_DEBUG_RETURN; 889 void check_possible_safepoint() NOT_DEBUG_RETURN; 890 891 #ifdef ASSERT 892 private: 893 volatile uint64_t _visited_for_critical_count; 894 895 public: 896 void set_visited_for_critical_count(uint64_t safepoint_id) { 897 assert(_visited_for_critical_count == 0, "Must be reset before set"); 898 assert((safepoint_id & 0x1) == 1, "Must be odd"); 899 _visited_for_critical_count = safepoint_id; 900 } 901 void reset_visited_for_critical_count(uint64_t safepoint_id) { 902 assert(_visited_for_critical_count == safepoint_id, "Was not visited"); 903 _visited_for_critical_count = 0; 904 } 905 bool was_visited_for_critical_count(uint64_t safepoint_id) const { 906 return _visited_for_critical_count == safepoint_id; 907 } 908 #endif // ASSERT 909 910 // JavaThread termination support 911 public: 912 enum TerminatedTypes { 913 _not_terminated = 0xDEAD - 2, 914 _thread_exiting, // JavaThread::exit() has been called for this thread 915 _thread_terminated, // JavaThread is removed from thread list 916 _vm_exited // JavaThread is still executing native code, but VM is terminated 917 // only VM_Exit can set _vm_exited 918 }; 919 920 private: 921 // In general a JavaThread's _terminated field transitions as follows: 922 // 923 // _not_terminated => _thread_exiting => _thread_terminated 924 // 925 // _vm_exited is a special value to cover the case of a JavaThread 926 // executing native code after the VM itself is terminated. 927 volatile TerminatedTypes _terminated; 928 929 jint _in_deopt_handler; // count of deoptimization 930 // handlers thread is in 931 volatile bool _doing_unsafe_access; // Thread may fault due to unsafe access 932 bool _do_not_unlock_if_synchronized; // Do not unlock the receiver of a synchronized method (since it was 933 // never locked) when throwing an exception. Used by interpreter only. 934 935 // JNI attach states: 936 enum JNIAttachStates { 937 _not_attaching_via_jni = 1, // thread is not attaching via JNI 938 _attaching_via_jni, // thread is attaching via JNI 939 _attached_via_jni // thread has attached via JNI 940 }; 941 942 // A regular JavaThread's _jni_attach_state is _not_attaching_via_jni. 943 // A native thread that is attaching via JNI starts with a value 944 // of _attaching_via_jni and transitions to _attached_via_jni. 945 volatile JNIAttachStates _jni_attach_state; 946 947 948 #if INCLUDE_JVMCI 949 // The _pending_* fields below are used to communicate extra information 950 // from an uncommon trap in JVMCI compiled code to the uncommon trap handler. 951 952 // Communicates the DeoptReason and DeoptAction of the uncommon trap 953 int _pending_deoptimization; 954 955 // Specifies whether the uncommon trap is to bci 0 of a synchronized method 956 // before the monitor has been acquired. 957 bool _pending_monitorenter; 958 959 // Specifies if the DeoptReason for the last uncommon trap was Reason_transfer_to_interpreter 960 bool _pending_transfer_to_interpreter; 961 962 // True if in a runtime call from compiled code that will deoptimize 963 // and re-execute a failed heap allocation in the interpreter. 964 bool _in_retryable_allocation; 965 966 // An id of a speculation that JVMCI compiled code can use to further describe and 967 // uniquely identify the speculative optimization guarded by an uncommon trap. 968 // See JVMCINMethodData::SPECULATION_LENGTH_BITS for further details. 969 jlong _pending_failed_speculation; 970 971 // These fields are mutually exclusive in terms of live ranges. 972 union { 973 // Communicates the pc at which the most recent implicit exception occurred 974 // from the signal handler to a deoptimization stub. 975 address _implicit_exception_pc; 976 977 // Communicates an alternative call target to an i2c stub from a JavaCall . 978 address _alternate_call_target; 979 } _jvmci; 980 981 // Support for high precision, thread sensitive counters in JVMCI compiled code. 982 jlong* _jvmci_counters; 983 984 // Fast thread locals for use by JVMCI 985 jlong _jvmci_reserved0; 986 jlong _jvmci_reserved1; 987 oop _jvmci_reserved_oop0; 988 989 public: 990 static jlong* _jvmci_old_thread_counters; 991 static void collect_counters(jlong* array, int length); 992 993 bool resize_counters(int current_size, int new_size); 994 995 static bool resize_all_jvmci_counters(int new_size); 996 997 void set_jvmci_reserved_oop0(oop value) { 998 _jvmci_reserved_oop0 = value; 999 } 1000 1001 oop get_jvmci_reserved_oop0() { 1002 return _jvmci_reserved_oop0; 1003 } 1004 1005 void set_jvmci_reserved0(jlong value) { 1006 _jvmci_reserved0 = value; 1007 } 1008 1009 jlong get_jvmci_reserved0() { 1010 return _jvmci_reserved0; 1011 } 1012 1013 void set_jvmci_reserved1(jlong value) { 1014 _jvmci_reserved1 = value; 1015 } 1016 1017 jlong get_jvmci_reserved1() { 1018 return _jvmci_reserved1; 1019 } 1020 1021 private: 1022 #endif // INCLUDE_JVMCI 1023 1024 StackOverflow _stack_overflow_state; 1025 1026 // Compiler exception handling (NOTE: The _exception_oop is *NOT* the same as _pending_exception. It is 1027 // used to temp. parsing values into and out of the runtime system during exception handling for compiled 1028 // code) 1029 volatile oop _exception_oop; // Exception thrown in compiled code 1030 volatile address _exception_pc; // PC where exception happened 1031 volatile address _exception_handler_pc; // PC for handler of exception 1032 volatile int _is_method_handle_return; // true (== 1) if the current exception PC is a MethodHandle call site. 1033 1034 private: 1035 // support for JNI critical regions 1036 jint _jni_active_critical; // count of entries into JNI critical region 1037 1038 // Checked JNI: function name requires exception check 1039 char* _pending_jni_exception_check_fn; 1040 1041 // For deadlock detection. 1042 int _depth_first_number; 1043 1044 // JVMTI PopFrame support 1045 // This is set to popframe_pending to signal that top Java frame should be popped immediately 1046 int _popframe_condition; 1047 1048 // If reallocation of scalar replaced objects fails, we throw OOM 1049 // and during exception propagation, pop the top 1050 // _frames_to_pop_failed_realloc frames, the ones that reference 1051 // failed reallocations. 1052 int _frames_to_pop_failed_realloc; 1053 1054 friend class VMThread; 1055 friend class ThreadWaitTransition; 1056 friend class VM_Exit; 1057 1058 // Stack watermark barriers. 1059 StackWatermarks _stack_watermarks; 1060 1061 public: 1062 inline StackWatermarks* stack_watermarks() { return &_stack_watermarks; } 1063 1064 public: 1065 // Constructor 1066 JavaThread(); // delegating constructor 1067 JavaThread(bool is_attaching_via_jni); // for main thread and JNI attached threads 1068 JavaThread(ThreadFunction entry_point, size_t stack_size = 0); 1069 ~JavaThread(); 1070 1071 #ifdef ASSERT 1072 // verify this JavaThread hasn't be published in the Threads::list yet 1073 void verify_not_published(); 1074 #endif // ASSERT 1075 1076 StackOverflow* stack_overflow_state() { return &_stack_overflow_state; } 1077 1078 //JNI functiontable getter/setter for JVMTI jni function table interception API. 1079 void set_jni_functions(struct JNINativeInterface_* functionTable) { 1080 _jni_environment.functions = functionTable; 1081 } 1082 struct JNINativeInterface_* get_jni_functions() { 1083 return (struct JNINativeInterface_ *)_jni_environment.functions; 1084 } 1085 1086 // This function is called at thread creation to allow 1087 // platform specific thread variables to be initialized. 1088 void cache_global_variables(); 1089 1090 // Executes Shutdown.shutdown() 1091 void invoke_shutdown_hooks(); 1092 1093 // Cleanup on thread exit 1094 enum ExitType { 1095 normal_exit, 1096 jni_detach 1097 }; 1098 void exit(bool destroy_vm, ExitType exit_type = normal_exit); 1099 1100 void cleanup_failed_attach_current_thread(bool is_daemon); 1101 1102 // Testers 1103 virtual bool is_Java_thread() const { return true; } 1104 virtual bool can_call_java() const { return true; } 1105 1106 virtual bool is_active_Java_thread() const { 1107 return on_thread_list() && !is_terminated(); 1108 } 1109 1110 // Thread oop. threadObj() can be NULL for initial JavaThread 1111 // (or for threads attached via JNI) 1112 oop threadObj() const; 1113 void set_threadObj(oop p); 1114 1115 // Prepare thread and add to priority queue. If a priority is 1116 // not specified, use the priority of the thread object. Threads_lock 1117 // must be held while this function is called. 1118 void prepare(jobject jni_thread, ThreadPriority prio=NoPriority); 1119 1120 void set_saved_exception_pc(address pc) { _saved_exception_pc = pc; } 1121 address saved_exception_pc() { return _saved_exception_pc; } 1122 1123 ThreadFunction entry_point() const { return _entry_point; } 1124 1125 // Allocates a new Java level thread object for this thread. thread_name may be NULL. 1126 void allocate_threadObj(Handle thread_group, const char* thread_name, bool daemon, TRAPS); 1127 1128 // Last frame anchor routines 1129 1130 JavaFrameAnchor* frame_anchor(void) { return &_anchor; } 1131 1132 // last_Java_sp 1133 bool has_last_Java_frame() const { return _anchor.has_last_Java_frame(); } 1134 intptr_t* last_Java_sp() const { return _anchor.last_Java_sp(); } 1135 1136 // last_Java_pc 1137 1138 address last_Java_pc(void) { return _anchor.last_Java_pc(); } 1139 1140 // Safepoint support 1141 inline JavaThreadState thread_state() const; 1142 inline void set_thread_state(JavaThreadState s); 1143 inline void set_thread_state_fence(JavaThreadState s); // fence after setting thread state 1144 inline ThreadSafepointState* safepoint_state() const; 1145 inline void set_safepoint_state(ThreadSafepointState* state); 1146 inline bool is_at_poll_safepoint(); 1147 1148 // JavaThread termination and lifecycle support: 1149 void smr_delete(); 1150 bool on_thread_list() const { return _on_thread_list; } 1151 void set_on_thread_list() { _on_thread_list = true; } 1152 1153 // thread has called JavaThread::exit() or is terminated 1154 bool is_exiting() const; 1155 // thread is terminated (no longer on the threads list); we compare 1156 // against the two non-terminated values so that a freed JavaThread 1157 // will also be considered terminated. 1158 bool check_is_terminated(TerminatedTypes l_terminated) const { 1159 return l_terminated != _not_terminated && l_terminated != _thread_exiting; 1160 } 1161 bool is_terminated() const; 1162 void set_terminated(TerminatedTypes t); 1163 1164 void block_if_vm_exited(); 1165 1166 bool doing_unsafe_access() { return _doing_unsafe_access; } 1167 void set_doing_unsafe_access(bool val) { _doing_unsafe_access = val; } 1168 1169 bool do_not_unlock_if_synchronized() { return _do_not_unlock_if_synchronized; } 1170 void set_do_not_unlock_if_synchronized(bool val) { _do_not_unlock_if_synchronized = val; } 1171 1172 SafepointMechanism::ThreadData* poll_data() { return &_poll_data; } 1173 1174 void set_requires_cross_modify_fence(bool val) PRODUCT_RETURN NOT_PRODUCT({ _requires_cross_modify_fence = val; }) 1175 1176 private: 1177 DEBUG_ONLY(void verify_frame_info();) 1178 1179 // Support for thread handshake operations 1180 HandshakeState _handshake; 1181 public: 1182 HandshakeState* handshake_state() { return &_handshake; } 1183 1184 // A JavaThread can always safely operate on it self and other threads 1185 // can do it safely if they are the active handshaker. 1186 bool is_handshake_safe_for(Thread* th) const { 1187 return _handshake.active_handshaker() == th || this == th; 1188 } 1189 1190 // Suspend/resume support for JavaThread 1191 bool java_suspend(); // higher-level suspension logic called by the public APIs 1192 bool java_resume(); // higher-level resume logic called by the public APIs 1193 bool is_suspended() { return _handshake.is_suspended(); } 1194 1195 // Check for async exception in addition to safepoint. 1196 static void check_special_condition_for_native_trans(JavaThread *thread); 1197 1198 // Synchronize with another thread that is deoptimizing objects of the 1199 // current thread, i.e. reverts optimizations based on escape analysis. 1200 void wait_for_object_deoptimization(); 1201 1202 // these next two are also used for self-suspension and async exception support 1203 void handle_special_runtime_exit_condition(bool check_asyncs = true); 1204 1205 // Return true if JavaThread has an asynchronous condition or 1206 // if external suspension is requested. 1207 bool has_special_runtime_exit_condition() { 1208 return (_async_exception_condition != _no_async_condition) || 1209 (_suspend_flags & (_obj_deopt JFR_ONLY(| _trace_flag))) != 0; 1210 } 1211 1212 // Fast-locking support 1213 bool is_lock_owned(address adr) const; 1214 1215 // Accessors for vframe array top 1216 // The linked list of vframe arrays are sorted on sp. This means when we 1217 // unpack the head must contain the vframe array to unpack. 1218 void set_vframe_array_head(vframeArray* value) { _vframe_array_head = value; } 1219 vframeArray* vframe_array_head() const { return _vframe_array_head; } 1220 1221 // Side structure for deferring update of java frame locals until deopt occurs 1222 JvmtiDeferredUpdates* deferred_updates() const { return _jvmti_deferred_updates; } 1223 void set_deferred_updates(JvmtiDeferredUpdates* du) { _jvmti_deferred_updates = du; } 1224 1225 // These only really exist to make debugging deopt problems simpler 1226 1227 void set_vframe_array_last(vframeArray* value) { _vframe_array_last = value; } 1228 vframeArray* vframe_array_last() const { return _vframe_array_last; } 1229 1230 // The special resourceMark used during deoptimization 1231 1232 void set_deopt_mark(DeoptResourceMark* value) { _deopt_mark = value; } 1233 DeoptResourceMark* deopt_mark(void) { return _deopt_mark; } 1234 1235 void set_deopt_compiled_method(CompiledMethod* nm) { _deopt_nmethod = nm; } 1236 CompiledMethod* deopt_compiled_method() { return _deopt_nmethod; } 1237 1238 Method* callee_target() const { return _callee_target; } 1239 void set_callee_target (Method* x) { _callee_target = x; } 1240 1241 // Oop results of vm runtime calls 1242 oop vm_result() const { return _vm_result; } 1243 void set_vm_result (oop x) { _vm_result = x; } 1244 1245 Metadata* vm_result_2() const { return _vm_result_2; } 1246 void set_vm_result_2 (Metadata* x) { _vm_result_2 = x; } 1247 1248 MemRegion deferred_card_mark() const { return _deferred_card_mark; } 1249 void set_deferred_card_mark(MemRegion mr) { _deferred_card_mark = mr; } 1250 1251 #if INCLUDE_JVMCI 1252 int pending_deoptimization() const { return _pending_deoptimization; } 1253 jlong pending_failed_speculation() const { return _pending_failed_speculation; } 1254 bool has_pending_monitorenter() const { return _pending_monitorenter; } 1255 void set_pending_monitorenter(bool b) { _pending_monitorenter = b; } 1256 void set_pending_deoptimization(int reason) { _pending_deoptimization = reason; } 1257 void set_pending_failed_speculation(jlong failed_speculation) { _pending_failed_speculation = failed_speculation; } 1258 void set_pending_transfer_to_interpreter(bool b) { _pending_transfer_to_interpreter = b; } 1259 void set_jvmci_alternate_call_target(address a) { assert(_jvmci._alternate_call_target == NULL, "must be"); _jvmci._alternate_call_target = a; } 1260 void set_jvmci_implicit_exception_pc(address a) { assert(_jvmci._implicit_exception_pc == NULL, "must be"); _jvmci._implicit_exception_pc = a; } 1261 1262 virtual bool in_retryable_allocation() const { return _in_retryable_allocation; } 1263 void set_in_retryable_allocation(bool b) { _in_retryable_allocation = b; } 1264 #endif // INCLUDE_JVMCI 1265 1266 // Exception handling for compiled methods 1267 oop exception_oop() const; 1268 address exception_pc() const { return _exception_pc; } 1269 address exception_handler_pc() const { return _exception_handler_pc; } 1270 bool is_method_handle_return() const { return _is_method_handle_return == 1; } 1271 1272 void set_exception_oop(oop o); 1273 void set_exception_pc(address a) { _exception_pc = a; } 1274 void set_exception_handler_pc(address a) { _exception_handler_pc = a; } 1275 void set_is_method_handle_return(bool value) { _is_method_handle_return = value ? 1 : 0; } 1276 1277 void clear_exception_oop_and_pc() { 1278 set_exception_oop(NULL); 1279 set_exception_pc(NULL); 1280 } 1281 1282 // Check if address is in the usable part of the stack (excludes protected 1283 // guard pages). Can be applied to any thread and is an approximation for 1284 // using is_in_live_stack when the query has to happen from another thread. 1285 bool is_in_usable_stack(address adr) const { 1286 return is_in_stack_range_incl(adr, _stack_overflow_state.stack_reserved_zone_base()); 1287 } 1288 1289 // Misc. accessors/mutators 1290 void set_do_not_unlock(void) { _do_not_unlock_if_synchronized = true; } 1291 void clr_do_not_unlock(void) { _do_not_unlock_if_synchronized = false; } 1292 bool do_not_unlock(void) { return _do_not_unlock_if_synchronized; } 1293 1294 // For assembly stub generation 1295 static ByteSize threadObj_offset() { return byte_offset_of(JavaThread, _threadObj); } 1296 static ByteSize jni_environment_offset() { return byte_offset_of(JavaThread, _jni_environment); } 1297 static ByteSize pending_jni_exception_check_fn_offset() { 1298 return byte_offset_of(JavaThread, _pending_jni_exception_check_fn); 1299 } 1300 static ByteSize last_Java_sp_offset() { 1301 return byte_offset_of(JavaThread, _anchor) + JavaFrameAnchor::last_Java_sp_offset(); 1302 } 1303 static ByteSize last_Java_pc_offset() { 1304 return byte_offset_of(JavaThread, _anchor) + JavaFrameAnchor::last_Java_pc_offset(); 1305 } 1306 static ByteSize frame_anchor_offset() { 1307 return byte_offset_of(JavaThread, _anchor); 1308 } 1309 static ByteSize callee_target_offset() { return byte_offset_of(JavaThread, _callee_target); } 1310 static ByteSize vm_result_offset() { return byte_offset_of(JavaThread, _vm_result); } 1311 static ByteSize vm_result_2_offset() { return byte_offset_of(JavaThread, _vm_result_2); } 1312 static ByteSize thread_state_offset() { return byte_offset_of(JavaThread, _thread_state); } 1313 static ByteSize polling_word_offset() { return byte_offset_of(JavaThread, _poll_data) + byte_offset_of(SafepointMechanism::ThreadData, _polling_word);} 1314 static ByteSize polling_page_offset() { return byte_offset_of(JavaThread, _poll_data) + byte_offset_of(SafepointMechanism::ThreadData, _polling_page);} 1315 static ByteSize saved_exception_pc_offset() { return byte_offset_of(JavaThread, _saved_exception_pc); } 1316 static ByteSize osthread_offset() { return byte_offset_of(JavaThread, _osthread); } 1317 #if INCLUDE_JVMCI 1318 static ByteSize pending_deoptimization_offset() { return byte_offset_of(JavaThread, _pending_deoptimization); } 1319 static ByteSize pending_monitorenter_offset() { return byte_offset_of(JavaThread, _pending_monitorenter); } 1320 static ByteSize pending_failed_speculation_offset() { return byte_offset_of(JavaThread, _pending_failed_speculation); } 1321 static ByteSize jvmci_alternate_call_target_offset() { return byte_offset_of(JavaThread, _jvmci._alternate_call_target); } 1322 static ByteSize jvmci_implicit_exception_pc_offset() { return byte_offset_of(JavaThread, _jvmci._implicit_exception_pc); } 1323 static ByteSize jvmci_counters_offset() { return byte_offset_of(JavaThread, _jvmci_counters); } 1324 #endif // INCLUDE_JVMCI 1325 static ByteSize exception_oop_offset() { return byte_offset_of(JavaThread, _exception_oop); } 1326 static ByteSize exception_pc_offset() { return byte_offset_of(JavaThread, _exception_pc); } 1327 static ByteSize exception_handler_pc_offset() { return byte_offset_of(JavaThread, _exception_handler_pc); } 1328 static ByteSize is_method_handle_return_offset() { return byte_offset_of(JavaThread, _is_method_handle_return); } 1329 1330 // StackOverflow offsets 1331 static ByteSize stack_overflow_limit_offset() { 1332 return byte_offset_of(JavaThread, _stack_overflow_state._stack_overflow_limit); 1333 } 1334 static ByteSize stack_guard_state_offset() { 1335 return byte_offset_of(JavaThread, _stack_overflow_state._stack_guard_state); 1336 } 1337 static ByteSize reserved_stack_activation_offset() { 1338 return byte_offset_of(JavaThread, _stack_overflow_state._reserved_stack_activation); 1339 } 1340 1341 static ByteSize suspend_flags_offset() { return byte_offset_of(JavaThread, _suspend_flags); } 1342 1343 static ByteSize do_not_unlock_if_synchronized_offset() { return byte_offset_of(JavaThread, _do_not_unlock_if_synchronized); } 1344 static ByteSize should_post_on_exceptions_flag_offset() { 1345 return byte_offset_of(JavaThread, _should_post_on_exceptions_flag); 1346 } 1347 static ByteSize doing_unsafe_access_offset() { return byte_offset_of(JavaThread, _doing_unsafe_access); } 1348 NOT_PRODUCT(static ByteSize requires_cross_modify_fence_offset() { return byte_offset_of(JavaThread, _requires_cross_modify_fence); }) 1349 1350 // Returns the jni environment for this thread 1351 JNIEnv* jni_environment() { return &_jni_environment; } 1352 1353 static JavaThread* thread_from_jni_environment(JNIEnv* env) { 1354 JavaThread *thread_from_jni_env = (JavaThread*)((intptr_t)env - in_bytes(jni_environment_offset())); 1355 // Only return NULL if thread is off the thread list; starting to 1356 // exit should not return NULL. 1357 if (thread_from_jni_env->is_terminated()) { 1358 thread_from_jni_env->block_if_vm_exited(); 1359 return NULL; 1360 } else { 1361 return thread_from_jni_env; 1362 } 1363 } 1364 1365 // JNI critical regions. These can nest. 1366 bool in_critical() { return _jni_active_critical > 0; } 1367 bool in_last_critical() { return _jni_active_critical == 1; } 1368 inline void enter_critical(); 1369 void exit_critical() { 1370 assert(Thread::current() == this, "this must be current thread"); 1371 _jni_active_critical--; 1372 assert(_jni_active_critical >= 0, "JNI critical nesting problem?"); 1373 } 1374 1375 // Checked JNI: is the programmer required to check for exceptions, if so specify 1376 // which function name. Returning to a Java frame should implicitly clear the 1377 // pending check, this is done for Native->Java transitions (i.e. user JNI code). 1378 // VM->Java transistions are not cleared, it is expected that JNI code enclosed 1379 // within ThreadToNativeFromVM makes proper exception checks (i.e. VM internal). 1380 bool is_pending_jni_exception_check() const { return _pending_jni_exception_check_fn != NULL; } 1381 void clear_pending_jni_exception_check() { _pending_jni_exception_check_fn = NULL; } 1382 const char* get_pending_jni_exception_check() const { return _pending_jni_exception_check_fn; } 1383 void set_pending_jni_exception_check(const char* fn_name) { _pending_jni_exception_check_fn = (char*) fn_name; } 1384 1385 // For deadlock detection 1386 int depth_first_number() { return _depth_first_number; } 1387 void set_depth_first_number(int dfn) { _depth_first_number = dfn; } 1388 1389 private: 1390 void set_monitor_chunks(MonitorChunk* monitor_chunks) { _monitor_chunks = monitor_chunks; } 1391 1392 public: 1393 MonitorChunk* monitor_chunks() const { return _monitor_chunks; } 1394 void add_monitor_chunk(MonitorChunk* chunk); 1395 void remove_monitor_chunk(MonitorChunk* chunk); 1396 bool in_deopt_handler() const { return _in_deopt_handler > 0; } 1397 void inc_in_deopt_handler() { _in_deopt_handler++; } 1398 void dec_in_deopt_handler() { 1399 assert(_in_deopt_handler > 0, "mismatched deopt nesting"); 1400 if (_in_deopt_handler > 0) { // robustness 1401 _in_deopt_handler--; 1402 } 1403 } 1404 1405 private: 1406 void set_entry_point(ThreadFunction entry_point) { _entry_point = entry_point; } 1407 1408 public: 1409 1410 // Frame iteration; calls the function f for all frames on the stack 1411 void frames_do(void f(frame*, const RegisterMap*)); 1412 1413 // Memory operations 1414 void oops_do_frames(OopClosure* f, CodeBlobClosure* cf); 1415 void oops_do_no_frames(OopClosure* f, CodeBlobClosure* cf); 1416 1417 // Sweeper operations 1418 virtual void nmethods_do(CodeBlobClosure* cf); 1419 1420 // RedefineClasses Support 1421 void metadata_do(MetadataClosure* f); 1422 1423 // Debug method asserting thread states are correct during a handshake operation. 1424 DEBUG_ONLY(void verify_states_for_handshake();) 1425 1426 // Misc. operations 1427 char* name() const { return (char*)get_thread_name(); } 1428 static const char* name_for(oop thread_obj); 1429 void print_on(outputStream* st, bool print_extended_info) const; 1430 void print_on(outputStream* st) const { print_on(st, false); } 1431 void print() const; 1432 void print_thread_state_on(outputStream*) const PRODUCT_RETURN; 1433 void print_on_error(outputStream* st, char* buf, int buflen) const; 1434 void print_name_on_error(outputStream* st, char* buf, int buflen) const; 1435 void verify(); 1436 const char* get_thread_name() const; 1437 protected: 1438 // factor out low-level mechanics for use in both normal and error cases 1439 virtual const char* get_thread_name_string(char* buf = NULL, int buflen = 0) const; 1440 public: 1441 // Accessing frames 1442 frame last_frame() { 1443 _anchor.make_walkable(); 1444 return pd_last_frame(); 1445 } 1446 javaVFrame* last_java_vframe(RegisterMap* reg_map); 1447 1448 // Returns method at 'depth' java or native frames down the stack 1449 // Used for security checks 1450 Klass* security_get_caller_class(int depth); 1451 1452 // Print stack trace in external format 1453 void print_stack_on(outputStream* st); 1454 void print_stack() { print_stack_on(tty); } 1455 // Print current stack trace for checked JNI warnings and JNI fatal errors. 1456 // This is the external format from above, but selecting the platform 1457 // as applicable. 1458 void print_jni_stack(); 1459 1460 // Print stack traces in various internal formats 1461 void trace_stack() PRODUCT_RETURN; 1462 void trace_stack_from(vframe* start_vf) PRODUCT_RETURN; 1463 void trace_frames() PRODUCT_RETURN; 1464 1465 // Print an annotated view of the stack frames 1466 void print_frame_layout(int depth = 0, bool validate_only = false) NOT_DEBUG_RETURN; 1467 void validate_frame_layout() { 1468 print_frame_layout(0, true); 1469 } 1470 1471 // Function for testing deoptimization 1472 void deoptimize(); 1473 void make_zombies(); 1474 1475 void deoptimize_marked_methods(); 1476 1477 public: 1478 // Returns the running thread as a JavaThread 1479 static inline JavaThread* current(); 1480 // Returns the current thread as a JavaThread, or NULL if not attached 1481 static inline JavaThread* current_or_null(); 1482 1483 // Returns the active Java thread. Do not use this if you know you are calling 1484 // from a JavaThread, as it's slower than JavaThread::current. If called from 1485 // the VMThread, it also returns the JavaThread that instigated the VMThread's 1486 // operation. You may not want that either. 1487 static JavaThread* active(); 1488 1489 protected: 1490 virtual void pre_run(); 1491 virtual void run(); 1492 void thread_main_inner(); 1493 virtual void post_run(); 1494 1495 public: 1496 // Thread local information maintained by JVMTI. 1497 void set_jvmti_thread_state(JvmtiThreadState *value) { _jvmti_thread_state = value; } 1498 // A JvmtiThreadState is lazily allocated. This jvmti_thread_state() 1499 // getter is used to get this JavaThread's JvmtiThreadState if it has 1500 // one which means NULL can be returned. JvmtiThreadState::state_for() 1501 // is used to get the specified JavaThread's JvmtiThreadState if it has 1502 // one or it allocates a new JvmtiThreadState for the JavaThread and 1503 // returns it. JvmtiThreadState::state_for() will return NULL only if 1504 // the specified JavaThread is exiting. 1505 JvmtiThreadState *jvmti_thread_state() const { return _jvmti_thread_state; } 1506 static ByteSize jvmti_thread_state_offset() { return byte_offset_of(JavaThread, _jvmti_thread_state); } 1507 1508 // JVMTI PopFrame support 1509 // Setting and clearing popframe_condition 1510 // All of these enumerated values are bits. popframe_pending 1511 // indicates that a PopFrame() has been requested and not yet been 1512 // completed. popframe_processing indicates that that PopFrame() is in 1513 // the process of being completed. popframe_force_deopt_reexecution_bit 1514 // indicates that special handling is required when returning to a 1515 // deoptimized caller. 1516 enum PopCondition { 1517 popframe_inactive = 0x00, 1518 popframe_pending_bit = 0x01, 1519 popframe_processing_bit = 0x02, 1520 popframe_force_deopt_reexecution_bit = 0x04 1521 }; 1522 PopCondition popframe_condition() { return (PopCondition) _popframe_condition; } 1523 void set_popframe_condition(PopCondition c) { _popframe_condition = c; } 1524 void set_popframe_condition_bit(PopCondition c) { _popframe_condition |= c; } 1525 void clear_popframe_condition() { _popframe_condition = popframe_inactive; } 1526 static ByteSize popframe_condition_offset() { return byte_offset_of(JavaThread, _popframe_condition); } 1527 bool has_pending_popframe() { return (popframe_condition() & popframe_pending_bit) != 0; } 1528 bool popframe_forcing_deopt_reexecution() { return (popframe_condition() & popframe_force_deopt_reexecution_bit) != 0; } 1529 void clear_popframe_forcing_deopt_reexecution() { _popframe_condition &= ~popframe_force_deopt_reexecution_bit; } 1530 1531 bool pop_frame_in_process(void) { return ((_popframe_condition & popframe_processing_bit) != 0); } 1532 void set_pop_frame_in_process(void) { _popframe_condition |= popframe_processing_bit; } 1533 void clr_pop_frame_in_process(void) { _popframe_condition &= ~popframe_processing_bit; } 1534 1535 int frames_to_pop_failed_realloc() const { return _frames_to_pop_failed_realloc; } 1536 void set_frames_to_pop_failed_realloc(int nb) { _frames_to_pop_failed_realloc = nb; } 1537 void dec_frames_to_pop_failed_realloc() { _frames_to_pop_failed_realloc--; } 1538 1539 private: 1540 // Saved incoming arguments to popped frame. 1541 // Used only when popped interpreted frame returns to deoptimized frame. 1542 void* _popframe_preserved_args; 1543 int _popframe_preserved_args_size; 1544 1545 public: 1546 void popframe_preserve_args(ByteSize size_in_bytes, void* start); 1547 void* popframe_preserved_args(); 1548 ByteSize popframe_preserved_args_size(); 1549 WordSize popframe_preserved_args_size_in_words(); 1550 void popframe_free_preserved_args(); 1551 1552 1553 private: 1554 JvmtiThreadState *_jvmti_thread_state; 1555 1556 // Used by the interpreter in fullspeed mode for frame pop, method 1557 // entry, method exit and single stepping support. This field is 1558 // only set to non-zero at a safepoint or using a direct handshake 1559 // (see EnterInterpOnlyModeClosure). 1560 // It can be set to zero asynchronously to this threads execution (i.e., without 1561 // safepoint/handshake or a lock) so we have to be very careful. 1562 // Accesses by other threads are synchronized using JvmtiThreadState_lock though. 1563 int _interp_only_mode; 1564 1565 public: 1566 // used by the interpreter for fullspeed debugging support (see above) 1567 static ByteSize interp_only_mode_offset() { return byte_offset_of(JavaThread, _interp_only_mode); } 1568 bool is_interp_only_mode() { return (_interp_only_mode != 0); } 1569 int get_interp_only_mode() { return _interp_only_mode; } 1570 void increment_interp_only_mode() { ++_interp_only_mode; } 1571 void decrement_interp_only_mode() { --_interp_only_mode; } 1572 1573 // support for cached flag that indicates whether exceptions need to be posted for this thread 1574 // if this is false, we can avoid deoptimizing when events are thrown 1575 // this gets set to reflect whether jvmtiExport::post_exception_throw would actually do anything 1576 private: 1577 int _should_post_on_exceptions_flag; 1578 1579 public: 1580 int should_post_on_exceptions_flag() { return _should_post_on_exceptions_flag; } 1581 void set_should_post_on_exceptions_flag(int val) { _should_post_on_exceptions_flag = val; } 1582 1583 private: 1584 ThreadStatistics *_thread_stat; 1585 1586 public: 1587 ThreadStatistics* get_thread_stat() const { return _thread_stat; } 1588 1589 // Return a blocker object for which this thread is blocked parking. 1590 oop current_park_blocker(); 1591 1592 private: 1593 static size_t _stack_size_at_create; 1594 1595 public: 1596 static inline size_t stack_size_at_create(void) { 1597 return _stack_size_at_create; 1598 } 1599 static inline void set_stack_size_at_create(size_t value) { 1600 _stack_size_at_create = value; 1601 } 1602 1603 // Machine dependent stuff 1604 #include OS_CPU_HEADER(thread) 1605 1606 // JSR166 per-thread parker 1607 private: 1608 Parker _parker; 1609 public: 1610 Parker* parker() { return &_parker; } 1611 1612 // Biased locking support 1613 private: 1614 GrowableArray<MonitorInfo*>* _cached_monitor_info; 1615 public: 1616 GrowableArray<MonitorInfo*>* cached_monitor_info() { return _cached_monitor_info; } 1617 void set_cached_monitor_info(GrowableArray<MonitorInfo*>* info) { _cached_monitor_info = info; } 1618 1619 // clearing/querying jni attach status 1620 bool is_attaching_via_jni() const { return _jni_attach_state == _attaching_via_jni; } 1621 bool has_attached_via_jni() const { return is_attaching_via_jni() || _jni_attach_state == _attached_via_jni; } 1622 inline void set_done_attaching_via_jni(); 1623 1624 // Stack dump assistance: 1625 // Track the class we want to initialize but for which we have to wait 1626 // on its init_lock() because it is already being initialized. 1627 void set_class_to_be_initialized(InstanceKlass* k); 1628 InstanceKlass* class_to_be_initialized() const; 1629 1630 private: 1631 InstanceKlass* _class_to_be_initialized; 1632 1633 // java.lang.Thread.sleep support 1634 ParkEvent * _SleepEvent; 1635 public: 1636 bool sleep(jlong millis); 1637 1638 // java.lang.Thread interruption support 1639 void interrupt(); 1640 bool is_interrupted(bool clear_interrupted); 1641 1642 static OopStorage* thread_oop_storage(); 1643 1644 static void verify_cross_modify_fence_failure(JavaThread *thread) PRODUCT_RETURN; 1645 1646 // Helper function to start a VM-internal daemon thread. 1647 // E.g. ServiceThread, NotificationThread, CompilerThread etc. 1648 static void start_internal_daemon(JavaThread* current, JavaThread* target, 1649 Handle thread_oop, ThreadPriority prio); 1650 1651 // Helper function to do vm_exit_on_initialization for osthread 1652 // resource allocation failure. 1653 static void vm_exit_on_osthread_failure(JavaThread* thread); 1654 1655 // AsyncGetCallTrace support 1656 inline bool in_asgct(void) {return _in_asgct;} 1657 inline void set_in_asgct(bool value) {_in_asgct = value;} 1658 }; 1659 1660 // Inline implementation of JavaThread::current 1661 inline JavaThread* JavaThread::current() { 1662 return Thread::current()->as_Java_thread(); 1663 } 1664 1665 inline JavaThread* JavaThread::current_or_null() { 1666 Thread* current = Thread::current_or_null(); 1667 return current != nullptr ? current->as_Java_thread() : nullptr; 1668 } 1669 1670 inline JavaThread* Thread::as_Java_thread() { 1671 assert(is_Java_thread(), "incorrect cast to JavaThread"); 1672 return static_cast<JavaThread*>(this); 1673 } 1674 1675 inline const JavaThread* Thread::as_Java_thread() const { 1676 assert(is_Java_thread(), "incorrect cast to const JavaThread"); 1677 return static_cast<const JavaThread*>(this); 1678 } 1679 1680 // The active thread queue. It also keeps track of the current used 1681 // thread priorities. 1682 class Threads: AllStatic { 1683 friend class VMStructs; 1684 private: 1685 static int _number_of_threads; 1686 static int _number_of_non_daemon_threads; 1687 static int _return_code; 1688 static uintx _thread_claim_token; 1689 #ifdef ASSERT 1690 static bool _vm_complete; 1691 #endif 1692 1693 static void initialize_java_lang_classes(JavaThread* main_thread, TRAPS); 1694 static void initialize_jsr292_core_classes(TRAPS); 1695 1696 public: 1697 // Thread management 1698 // force_daemon is a concession to JNI, where we may need to add a 1699 // thread to the thread list before allocating its thread object 1700 static void add(JavaThread* p, bool force_daemon = false); 1701 static void remove(JavaThread* p, bool is_daemon); 1702 static void non_java_threads_do(ThreadClosure* tc); 1703 static void java_threads_do(ThreadClosure* tc); 1704 static void java_threads_and_vm_thread_do(ThreadClosure* tc); 1705 static void threads_do(ThreadClosure* tc); 1706 static void possibly_parallel_threads_do(bool is_par, ThreadClosure* tc); 1707 1708 // Initializes the vm and creates the vm thread 1709 static jint create_vm(JavaVMInitArgs* args, bool* canTryAgain); 1710 static void convert_vm_init_libraries_to_agents(); 1711 static void create_vm_init_libraries(); 1712 static void create_vm_init_agents(); 1713 static void shutdown_vm_agents(); 1714 static void destroy_vm(); 1715 // Supported VM versions via JNI 1716 // Includes JNI_VERSION_1_1 1717 static jboolean is_supported_jni_version_including_1_1(jint version); 1718 // Does not include JNI_VERSION_1_1 1719 static jboolean is_supported_jni_version(jint version); 1720 1721 // The "thread claim token" provides a way for threads to be claimed 1722 // by parallel worker tasks. 1723 // 1724 // Each thread contains a "token" field. A task will claim the 1725 // thread only if its token is different from the global token, 1726 // which is updated by calling change_thread_claim_token(). When 1727 // a thread is claimed, it's token is set to the global token value 1728 // so other threads in the same iteration pass won't claim it. 1729 // 1730 // For this to work change_thread_claim_token() needs to be called 1731 // exactly once in sequential code before starting parallel tasks 1732 // that should claim threads. 1733 // 1734 // New threads get their token set to 0 and change_thread_claim_token() 1735 // never sets the global token to 0. 1736 static uintx thread_claim_token() { return _thread_claim_token; } 1737 static void change_thread_claim_token(); 1738 static void assert_all_threads_claimed() NOT_DEBUG_RETURN; 1739 1740 // Apply "f->do_oop" to all root oops in all threads. 1741 // This version may only be called by sequential code. 1742 static void oops_do(OopClosure* f, CodeBlobClosure* cf); 1743 // This version may be called by sequential or parallel code. 1744 static void possibly_parallel_oops_do(bool is_par, OopClosure* f, CodeBlobClosure* cf); 1745 1746 // RedefineClasses support 1747 static void metadata_do(MetadataClosure* f); 1748 static void metadata_handles_do(void f(Metadata*)); 1749 1750 #ifdef ASSERT 1751 static bool is_vm_complete() { return _vm_complete; } 1752 #endif // ASSERT 1753 1754 // Verification 1755 static void verify(); 1756 static void print_on(outputStream* st, bool print_stacks, bool internal_format, bool print_concurrent_locks, bool print_extended_info); 1757 static void print(bool print_stacks, bool internal_format) { 1758 // this function is only used by debug.cpp 1759 print_on(tty, print_stacks, internal_format, false /* no concurrent lock printed */, false /* simple format */); 1760 } 1761 static void print_on_error(outputStream* st, Thread* current, char* buf, int buflen); 1762 static void print_on_error(Thread* this_thread, outputStream* st, Thread* current, char* buf, 1763 int buflen, bool* found_current); 1764 static void print_threads_compiling(outputStream* st, char* buf, int buflen, bool short_form = false); 1765 1766 // Get Java threads that are waiting to enter a monitor. 1767 static GrowableArray<JavaThread*>* get_pending_threads(ThreadsList * t_list, 1768 int count, address monitor); 1769 1770 // Get owning Java thread from the monitor's owner field. 1771 static JavaThread *owning_thread_from_monitor_owner(ThreadsList * t_list, 1772 address owner); 1773 1774 // Number of threads on the active threads list 1775 static int number_of_threads() { return _number_of_threads; } 1776 // Number of non-daemon threads on the active threads list 1777 static int number_of_non_daemon_threads() { return _number_of_non_daemon_threads; } 1778 1779 // Deoptimizes all frames tied to marked nmethods 1780 static void deoptimized_wrt_marked_nmethods(); 1781 1782 struct Test; // For private gtest access. 1783 }; 1784 1785 class UnlockFlagSaver { 1786 private: 1787 JavaThread* _thread; 1788 bool _do_not_unlock; 1789 public: 1790 UnlockFlagSaver(JavaThread* t) { 1791 _thread = t; 1792 _do_not_unlock = t->do_not_unlock_if_synchronized(); 1793 t->set_do_not_unlock_if_synchronized(false); 1794 } 1795 ~UnlockFlagSaver() { 1796 _thread->set_do_not_unlock_if_synchronized(_do_not_unlock); 1797 } 1798 }; 1799 1800 #endif // SHARE_RUNTIME_THREAD_HPP