rev 56251 : imported patch 8226705-v1

   1 /*
   2  * Copyright (c) 1997, 2019, 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_RUNTIME_THREAD_HPP
  26 #define SHARE_RUNTIME_THREAD_HPP
  27 
  28 #include "jni.h"
  29 #include "code/compiledMethod.hpp"
  30 #include "gc/shared/gcThreadLocalData.hpp"
  31 #include "gc/shared/threadLocalAllocBuffer.hpp"
  32 #include "memory/allocation.hpp"
  33 #include "oops/oop.hpp"
  34 #include "prims/jvmtiExport.hpp"
  35 #include "runtime/frame.hpp"
  36 #include "runtime/globals.hpp"
  37 #include "runtime/handshake.hpp"
  38 #include "runtime/javaFrameAnchor.hpp"
  39 #include "runtime/jniHandles.hpp"
  40 #include "runtime/mutexLocker.hpp"
  41 #include "runtime/os.hpp"
  42 #include "runtime/osThread.hpp"
  43 #include "runtime/park.hpp"
  44 #include "runtime/stubRoutines.hpp"
  45 #include "runtime/threadHeapSampler.hpp"
  46 #include "runtime/threadLocalStorage.hpp"
  47 #include "runtime/threadStatisticalInfo.hpp"
  48 #include "runtime/unhandledOops.hpp"
  49 #include "utilities/align.hpp"
  50 #include "utilities/exceptions.hpp"
  51 #include "utilities/macros.hpp"
  52 #ifdef ZERO
  53 # include "stack_zero.hpp"
  54 #endif
  55 #if INCLUDE_JFR
  56 #include "jfr/support/jfrThreadExtension.hpp"
  57 #endif
  58 
  59 
  60 class SafeThreadsListPtr;
  61 class ThreadSafepointState;
  62 class ThreadsList;
  63 class ThreadsSMRSupport;
  64 
  65 class JvmtiThreadState;
  66 class ThreadStatistics;
  67 class ConcurrentLocksDump;
  68 class ParkEvent;
  69 class Parker;
  70 class MonitorInfo;
  71 
  72 class ciEnv;
  73 class CompileThread;
  74 class CompileLog;
  75 class CompileTask;
  76 class CompileQueue;
  77 class CompilerCounters;
  78 
  79 class vframeArray;
  80 class vframe;
  81 class javaVFrame;
  82 
  83 class DeoptResourceMark;
  84 class jvmtiDeferredLocalVariableSet;
  85 
  86 class ThreadClosure;
  87 class ICRefillVerifier;
  88 class IdealGraphPrinter;
  89 
  90 class JVMCIEnv;
  91 class JVMCIPrimitiveArray;
  92 
  93 class Metadata;
  94 class ResourceArea;
  95 
  96 DEBUG_ONLY(class ResourceMark;)
  97 
  98 class WorkerThread;
  99 
 100 // Class hierarchy
 101 // - Thread
 102 //   - JavaThread
 103 //     - various subclasses eg CompilerThread, ServiceThread
 104 //   - NonJavaThread
 105 //     - NamedThread
 106 //       - VMThread
 107 //       - ConcurrentGCThread
 108 //       - WorkerThread
 109 //         - GangWorker
 110 //     - WatcherThread
 111 //     - JfrThreadSampler
 112 //
 113 // All Thread subclasses must be either JavaThread or NonJavaThread.
 114 // This means !t->is_Java_thread() iff t is a NonJavaThread, or t is
 115 // a partially constructed/destroyed Thread.
 116 
 117 // Thread execution sequence and actions:
 118 // All threads:
 119 //  - thread_native_entry  // per-OS native entry point
 120 //    - stack initialization
 121 //    - other OS-level initialization (signal masks etc)
 122 //    - handshake with creating thread (if not started suspended)
 123 //    - this->call_run()  // common shared entry point
 124 //      - shared common initialization
 125 //      - this->pre_run()  // virtual per-thread-type initialization
 126 //      - this->run()      // virtual per-thread-type "main" logic
 127 //      - shared common tear-down
 128 //      - this->post_run()  // virtual per-thread-type tear-down
 129 //      - // 'this' no longer referenceable
 130 //    - OS-level tear-down (minimal)
 131 //    - final logging
 132 //
 133 // For JavaThread:
 134 //   - this->run()  // virtual but not normally overridden
 135 //     - this->thread_main_inner()  // extra call level to ensure correct stack calculations
 136 //       - this->entry_point()  // set differently for each kind of JavaThread
 137 
 138 class Thread: public ThreadShadow {
 139   friend class VMStructs;
 140   friend class JVMCIVMStructs;
 141  private:
 142 
 143 #ifndef USE_LIBRARY_BASED_TLS_ONLY
 144   // Current thread is maintained as a thread-local variable
 145   static THREAD_LOCAL_DECL Thread* _thr_current;
 146 #endif
 147 
 148   // Thread local data area available to the GC. The internal
 149   // structure and contents of this data area is GC-specific.
 150   // Only GC and GC barrier code should access this data area.
 151   GCThreadLocalData _gc_data;
 152 
 153  public:
 154   static ByteSize gc_data_offset() {
 155     return byte_offset_of(Thread, _gc_data);
 156   }
 157 
 158   template <typename T> T* gc_data() {
 159     STATIC_ASSERT(sizeof(T) <= sizeof(_gc_data));
 160     return reinterpret_cast<T*>(&_gc_data);
 161   }
 162 
 163   // Exception handling
 164   // (Note: _pending_exception and friends are in ThreadShadow)
 165   //oop       _pending_exception;                // pending exception for current thread
 166   // const char* _exception_file;                   // file information for exception (debugging only)
 167   // int         _exception_line;                   // line information for exception (debugging only)
 168  protected:
 169 
 170   DEBUG_ONLY(static Thread* _starting_thread;)
 171 
 172   // Support for forcing alignment of thread objects for biased locking
 173   void*       _real_malloc_address;
 174 
 175   // JavaThread lifecycle support:
 176   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
 177   friend class ScanHazardPtrGatherProtectedThreadsClosure;  // for cmpxchg_threads_hazard_ptr(), get_threads_hazard_ptr(), is_hazard_ptr_tagged() access
 178   friend class ScanHazardPtrGatherThreadsListClosure;  // for get_threads_hazard_ptr(), untag_hazard_ptr() access
 179   friend class ScanHazardPtrPrintMatchingThreadsClosure;  // for get_threads_hazard_ptr(), is_hazard_ptr_tagged() access
 180   friend class ThreadsSMRSupport;  // for _nested_threads_hazard_ptr_cnt, _threads_hazard_ptr, _threads_list_ptr access
 181 
 182   ThreadsList* volatile _threads_hazard_ptr;
 183   SafeThreadsListPtr*   _threads_list_ptr;
 184   ThreadsList*          cmpxchg_threads_hazard_ptr(ThreadsList* exchange_value, ThreadsList* compare_value);
 185   ThreadsList*          get_threads_hazard_ptr();
 186   void                  set_threads_hazard_ptr(ThreadsList* new_list);
 187   static bool           is_hazard_ptr_tagged(ThreadsList* list) {
 188     return (intptr_t(list) & intptr_t(1)) == intptr_t(1);
 189   }
 190   static ThreadsList*   tag_hazard_ptr(ThreadsList* list) {
 191     return (ThreadsList*)(intptr_t(list) | intptr_t(1));
 192   }
 193   static ThreadsList*   untag_hazard_ptr(ThreadsList* list) {
 194     return (ThreadsList*)(intptr_t(list) & ~intptr_t(1));
 195   }
 196   // This field is enabled via -XX:+EnableThreadSMRStatistics:
 197   uint _nested_threads_hazard_ptr_cnt;
 198   void dec_nested_threads_hazard_ptr_cnt() {
 199     assert(_nested_threads_hazard_ptr_cnt != 0, "mismatched {dec,inc}_nested_threads_hazard_ptr_cnt()");
 200     _nested_threads_hazard_ptr_cnt--;
 201   }
 202   void inc_nested_threads_hazard_ptr_cnt() {
 203     _nested_threads_hazard_ptr_cnt++;
 204   }
 205   uint nested_threads_hazard_ptr_cnt() {
 206     return _nested_threads_hazard_ptr_cnt;
 207   }
 208 
 209  public:
 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  private:
 218 
 219   // ***************************************************************
 220   // Suspend and resume support
 221   // ***************************************************************
 222   //
 223   // VM suspend/resume no longer exists - it was once used for various
 224   // things including safepoints but was deprecated and finally removed
 225   // in Java 7. Because VM suspension was considered "internal" Java-level
 226   // suspension was considered "external", and this legacy naming scheme
 227   // remains.
 228   //
 229   // External suspend/resume requests come from JVM_SuspendThread,
 230   // JVM_ResumeThread, JVMTI SuspendThread, and finally JVMTI
 231   // ResumeThread. External
 232   // suspend requests cause _external_suspend to be set and external
 233   // resume requests cause _external_suspend to be cleared.
 234   // External suspend requests do not nest on top of other external
 235   // suspend requests. The higher level APIs reject suspend requests
 236   // for already suspended threads.
 237   //
 238   // The external_suspend
 239   // flag is checked by has_special_runtime_exit_condition() and java thread
 240   // will self-suspend when handle_special_runtime_exit_condition() is
 241   // called. Most uses of the _thread_blocked state in JavaThreads are
 242   // considered the same as being externally suspended; if the blocking
 243   // condition lifts, the JavaThread will self-suspend. Other places
 244   // where VM checks for external_suspend include:
 245   //   + mutex granting (do not enter monitors when thread is suspended)
 246   //   + state transitions from _thread_in_native
 247   //
 248   // In general, java_suspend() does not wait for an external suspend
 249   // request to complete. When it returns, the only guarantee is that
 250   // the _external_suspend field is true.
 251   //
 252   // wait_for_ext_suspend_completion() is used to wait for an external
 253   // suspend request to complete. External suspend requests are usually
 254   // followed by some other interface call that requires the thread to
 255   // be quiescent, e.g., GetCallTrace(). By moving the "wait time" into
 256   // the interface that requires quiescence, we give the JavaThread a
 257   // chance to self-suspend before we need it to be quiescent. This
 258   // improves overall suspend/query performance.
 259   //
 260   // _suspend_flags controls the behavior of java_ suspend/resume.
 261   // It must be set under the protection of SR_lock. Read from the flag is
 262   // OK without SR_lock as long as the value is only used as a hint.
 263   // (e.g., check _external_suspend first without lock and then recheck
 264   // inside SR_lock and finish the suspension)
 265   //
 266   // _suspend_flags is also overloaded for other "special conditions" so
 267   // that a single check indicates whether any special action is needed
 268   // eg. for async exceptions.
 269   // -------------------------------------------------------------------
 270   // Notes:
 271   // 1. The suspend/resume logic no longer uses ThreadState in OSThread
 272   // but we still update its value to keep other part of the system (mainly
 273   // JVMTI) happy. ThreadState is legacy code (see notes in
 274   // osThread.hpp).
 275   //
 276   // 2. It would be more natural if set_external_suspend() is private and
 277   // part of java_suspend(), but that probably would affect the suspend/query
 278   // performance. Need more investigation on this.
 279 
 280   // suspend/resume lock: used for self-suspend
 281   Monitor* _SR_lock;
 282 
 283  protected:
 284   enum SuspendFlags {
 285     // NOTE: avoid using the sign-bit as cc generates different test code
 286     //       when the sign-bit is used, and sometimes incorrectly - see CR 6398077
 287 
 288     _external_suspend       = 0x20000000U, // thread is asked to self suspend
 289     _ext_suspended          = 0x40000000U, // thread has self-suspended
 290 
 291     _has_async_exception    = 0x00000001U, // there is a pending async exception
 292     _critical_native_unlock = 0x00000002U, // Must call back to unlock JNI critical lock
 293 
 294     _trace_flag             = 0x00000004U  // call tracing backend
 295   };
 296 
 297   // various suspension related flags - atomically updated
 298   // overloaded for async exception checking in check_special_condition_for_native_trans.
 299   volatile uint32_t _suspend_flags;
 300 
 301  private:
 302   int _num_nested_signal;
 303 
 304   DEBUG_ONLY(bool _suspendible_thread;)
 305 
 306  public:
 307   void enter_signal_handler() { _num_nested_signal++; }
 308   void leave_signal_handler() { _num_nested_signal--; }
 309   bool is_inside_signal_handler() const { return _num_nested_signal > 0; }
 310 
 311   // Determines if a heap allocation failure will be retried
 312   // (e.g., by deoptimizing and re-executing in the interpreter).
 313   // In this case, the failed allocation must raise
 314   // Universe::out_of_memory_error_retry() and omit side effects
 315   // such as JVMTI events and handling -XX:+HeapDumpOnOutOfMemoryError
 316   // and -XX:OnOutOfMemoryError.
 317   virtual bool in_retryable_allocation() const { return false; }
 318 
 319 #ifdef ASSERT
 320   void set_suspendible_thread() {
 321     _suspendible_thread = true;
 322   }
 323 
 324   void clear_suspendible_thread() {
 325     _suspendible_thread = false;
 326   }
 327 
 328   bool is_suspendible_thread() { return _suspendible_thread; }
 329 #endif
 330 
 331  private:
 332   // Active_handles points to a block of handles
 333   JNIHandleBlock* _active_handles;
 334 
 335   // One-element thread local free list
 336   JNIHandleBlock* _free_handle_block;
 337 
 338   // Point to the last handle mark
 339   HandleMark* _last_handle_mark;
 340 
 341   // Claim value for parallel iteration over threads.
 342   uintx _threads_do_token;
 343 
 344   // Support for GlobalCounter
 345  private:
 346   volatile uintx _rcu_counter;
 347  public:
 348   volatile uintx* get_rcu_counter() {
 349     return &_rcu_counter;
 350   }
 351 
 352  public:
 353   void set_last_handle_mark(HandleMark* mark)   { _last_handle_mark = mark; }
 354   HandleMark* last_handle_mark() const          { return _last_handle_mark; }
 355  private:
 356 
 357 #ifdef ASSERT
 358   ICRefillVerifier* _missed_ic_stub_refill_verifier;
 359 
 360  public:
 361   ICRefillVerifier* missed_ic_stub_refill_verifier() {
 362     return _missed_ic_stub_refill_verifier;
 363   }
 364 
 365   void set_missed_ic_stub_refill_verifier(ICRefillVerifier* verifier) {
 366     _missed_ic_stub_refill_verifier = verifier;
 367   }
 368 #endif // ASSERT
 369 
 370  private:
 371 
 372   // Debug support for checking if code allows safepoints or not.
 373   // Safepoints in the VM can happen because of allocation, invoking a VM operation, or blocking on
 374   // mutex, or blocking on an object synchronizer (Java locking).
 375   // If _no_safepoint_count is non-zero, then an assertion failure will happen in any of
 376   // the above cases.
 377   //
 378   // The class NoSafepointVerifier is used to set this counter.
 379   //
 380   NOT_PRODUCT(int _no_safepoint_count;)         // If 0, thread allow a safepoint to happen
 381 
 382  private:
 383   // Used by SkipGCALot class.
 384   NOT_PRODUCT(bool _skip_gcalot;)               // Should we elide gc-a-lot?
 385 
 386   friend class GCLocker;
 387   friend class NoSafepointVerifier;
 388   friend class PauseNoSafepointVerifier;
 389 
 390   volatile void* _polling_page;                 // Thread local polling page
 391 
 392   ThreadLocalAllocBuffer _tlab;                 // Thread-local eden
 393   jlong _allocated_bytes;                       // Cumulative number of bytes allocated on
 394                                                 // the Java heap
 395   ThreadHeapSampler _heap_sampler;              // For use when sampling the memory.
 396 
 397   ThreadStatisticalInfo _statistical_info;      // Statistics about the thread
 398 
 399   JFR_ONLY(DEFINE_THREAD_LOCAL_FIELD_JFR;)      // Thread-local data for jfr
 400 
 401   int   _vm_operation_started_count;            // VM_Operation support
 402   int   _vm_operation_completed_count;          // VM_Operation support
 403 
 404   ObjectMonitor* _current_pending_monitor;      // ObjectMonitor this thread
 405                                                 // is waiting to lock
 406   bool _current_pending_monitor_is_from_java;   // locking is from Java code
 407 
 408   // ObjectMonitor on which this thread called Object.wait()
 409   ObjectMonitor* _current_waiting_monitor;
 410 
 411   // Per-thread ObjectMonitor lists:
 412  public:
 413   ObjectMonitor* om_free_list;                  // SLL of free ObjectMonitors
 414   int om_free_count;                            // # on om_free_list
 415   int om_free_provision;                        // # to try to allocate next
 416   ObjectMonitor* om_in_use_list;                // SLL of in-use ObjectMonitors
 417   int om_in_use_count;                          // # on om_in_use_list
 418 
 419 #ifdef ASSERT
 420  private:
 421   volatile uint64_t _visited_for_critical_count;
 422 
 423  public:
 424   void set_visited_for_critical_count(uint64_t safepoint_id) {
 425     assert(_visited_for_critical_count == 0, "Must be reset before set");
 426     assert((safepoint_id & 0x1) == 1, "Must be odd");
 427     _visited_for_critical_count = safepoint_id;
 428   }
 429   void reset_visited_for_critical_count(uint64_t safepoint_id) {
 430     assert(_visited_for_critical_count == safepoint_id, "Was not visited");
 431     _visited_for_critical_count = 0;
 432   }
 433   bool was_visited_for_critical_count(uint64_t safepoint_id) const {
 434     return _visited_for_critical_count == safepoint_id;
 435   }
 436 #endif
 437 
 438  public:
 439   enum {
 440     is_definitely_current_thread = true
 441   };
 442 
 443   // Constructor
 444   Thread();
 445   virtual ~Thread() = 0;        // Thread is abstract.
 446 
 447   // Manage Thread::current()
 448   void initialize_thread_current();
 449   static void clear_thread_current(); // TLS cleanup needed before threads terminate
 450 
 451  protected:
 452   // To be implemented by children.
 453   virtual void run() = 0;
 454   virtual void pre_run() = 0;
 455   virtual void post_run() = 0;  // Note: Thread must not be deleted prior to calling this!
 456 
 457 #ifdef ASSERT
 458   enum RunState {
 459     PRE_CALL_RUN,
 460     CALL_RUN,
 461     PRE_RUN,
 462     RUN,
 463     POST_RUN
 464     // POST_CALL_RUN - can't define this one as 'this' may be deleted when we want to set it
 465   };
 466   RunState _run_state;  // for lifecycle checks
 467 #endif
 468 
 469 
 470  public:
 471   // invokes <ChildThreadClass>::run(), with common preparations and cleanups.
 472   void call_run();
 473 
 474   // Testers
 475   virtual bool is_VM_thread()       const            { return false; }
 476   virtual bool is_Java_thread()     const            { return false; }
 477   virtual bool is_Compiler_thread() const            { return false; }
 478   virtual bool is_Code_cache_sweeper_thread() const  { return false; }
 479   virtual bool is_hidden_from_external_view() const  { return false; }
 480   virtual bool is_jvmti_agent_thread() const         { return false; }
 481   // True iff the thread can perform GC operations at a safepoint.
 482   // Generally will be true only of VM thread and parallel GC WorkGang
 483   // threads.
 484   virtual bool is_GC_task_thread() const             { return false; }
 485   virtual bool is_Watcher_thread() const             { return false; }
 486   virtual bool is_ConcurrentGC_thread() const        { return false; }
 487   virtual bool is_Named_thread() const               { return false; }
 488   virtual bool is_Worker_thread() const              { return false; }
 489 
 490   // Can this thread make Java upcalls
 491   virtual bool can_call_java() const                 { return false; }
 492 
 493   // Is this a JavaThread that is on the VM's current ThreadsList?
 494   // If so it must participate in the safepoint protocol.
 495   virtual bool is_active_Java_thread() const         { return false; }
 496 
 497   // Casts
 498   virtual WorkerThread* as_Worker_thread() const     { return NULL; }
 499 
 500   virtual char* name() const { return (char*)"Unknown thread"; }
 501 
 502   // Returns the current thread (ASSERTS if NULL)
 503   static inline Thread* current();
 504   // Returns the current thread, or NULL if not attached
 505   static inline Thread* current_or_null();
 506   // Returns the current thread, or NULL if not attached, and is
 507   // safe for use from signal-handlers
 508   static inline Thread* current_or_null_safe();
 509 
 510   // Common thread operations
 511 #ifdef ASSERT
 512   static void check_for_dangling_thread_pointer(Thread *thread);
 513 #endif
 514   static void set_priority(Thread* thread, ThreadPriority priority);
 515   static ThreadPriority get_priority(const Thread* const thread);
 516   static void start(Thread* thread);
 517   static void interrupt(Thread* thr);
 518   static bool is_interrupted(Thread* thr, bool clear_interrupted);
 519 
 520   void set_native_thread_name(const char *name) {
 521     assert(Thread::current() == this, "set_native_thread_name can only be called on the current thread");
 522     os::set_native_thread_name(name);
 523   }
 524 
 525   ObjectMonitor** om_in_use_list_addr()          { return (ObjectMonitor **)&om_in_use_list; }
 526   Monitor* SR_lock() const                       { return _SR_lock; }
 527 
 528   bool has_async_exception() const { return (_suspend_flags & _has_async_exception) != 0; }
 529 
 530   inline void set_suspend_flag(SuspendFlags f);
 531   inline void clear_suspend_flag(SuspendFlags f);
 532 
 533   inline void set_has_async_exception();
 534   inline void clear_has_async_exception();
 535 
 536   bool do_critical_native_unlock() const { return (_suspend_flags & _critical_native_unlock) != 0; }
 537 
 538   inline void set_critical_native_unlock();
 539   inline void clear_critical_native_unlock();
 540 
 541   inline void set_trace_flag();
 542   inline void clear_trace_flag();
 543 
 544   // Support for Unhandled Oop detection
 545   // Add the field for both, fastdebug and debug, builds to keep
 546   // Thread's fields layout the same.
 547   // Note: CHECK_UNHANDLED_OOPS is defined only for fastdebug build.
 548 #ifdef CHECK_UNHANDLED_OOPS
 549  private:
 550   UnhandledOops* _unhandled_oops;
 551 #elif defined(ASSERT)
 552  private:
 553   void* _unhandled_oops;
 554 #endif
 555 #ifdef CHECK_UNHANDLED_OOPS
 556  public:
 557   UnhandledOops* unhandled_oops() { return _unhandled_oops; }
 558   // Mark oop safe for gc.  It may be stack allocated but won't move.
 559   void allow_unhandled_oop(oop *op) {
 560     if (CheckUnhandledOops) unhandled_oops()->allow_unhandled_oop(op);
 561   }
 562   // Clear oops at safepoint so crashes point to unhandled oop violator
 563   void clear_unhandled_oops() {
 564     if (CheckUnhandledOops) unhandled_oops()->clear_unhandled_oops();
 565   }
 566 #endif // CHECK_UNHANDLED_OOPS
 567 
 568  public:
 569 #ifndef PRODUCT
 570   bool skip_gcalot()           { return _skip_gcalot; }
 571   void set_skip_gcalot(bool v) { _skip_gcalot = v;    }
 572 #endif
 573 
 574   // Installs a pending exception to be inserted later
 575   static void send_async_exception(oop thread_oop, oop java_throwable);
 576 
 577   // Resource area
 578   ResourceArea* resource_area() const            { return _resource_area; }
 579   void set_resource_area(ResourceArea* area)     { _resource_area = area; }
 580 
 581   OSThread* osthread() const                     { return _osthread;   }
 582   void set_osthread(OSThread* thread)            { _osthread = thread; }
 583 
 584   // JNI handle support
 585   JNIHandleBlock* active_handles() const         { return _active_handles; }
 586   void set_active_handles(JNIHandleBlock* block) { _active_handles = block; }
 587   JNIHandleBlock* free_handle_block() const      { return _free_handle_block; }
 588   void set_free_handle_block(JNIHandleBlock* block) { _free_handle_block = block; }
 589 
 590   // Internal handle support
 591   HandleArea* handle_area() const                { return _handle_area; }
 592   void set_handle_area(HandleArea* area)         { _handle_area = area; }
 593 
 594   GrowableArray<Metadata*>* metadata_handles() const          { return _metadata_handles; }
 595   void set_metadata_handles(GrowableArray<Metadata*>* handles){ _metadata_handles = handles; }
 596 
 597   // Thread-Local Allocation Buffer (TLAB) support
 598   ThreadLocalAllocBuffer& tlab()                 { return _tlab; }
 599   void initialize_tlab() {
 600     if (UseTLAB) {
 601       tlab().initialize();
 602     }
 603   }
 604 
 605   jlong allocated_bytes()               { return _allocated_bytes; }
 606   void set_allocated_bytes(jlong value) { _allocated_bytes = value; }
 607   void incr_allocated_bytes(jlong size) { _allocated_bytes += size; }
 608   inline jlong cooked_allocated_bytes();
 609 
 610   ThreadHeapSampler& heap_sampler()     { return _heap_sampler; }
 611 
 612   ThreadStatisticalInfo& statistical_info() { return _statistical_info; }
 613 
 614   JFR_ONLY(DEFINE_THREAD_LOCAL_ACCESSOR_JFR;)
 615 
 616   bool is_trace_suspend()               { return (_suspend_flags & _trace_flag) != 0; }
 617 
 618   // VM operation support
 619   int vm_operation_ticket()                      { return ++_vm_operation_started_count; }
 620   int vm_operation_completed_count()             { return _vm_operation_completed_count; }
 621   void increment_vm_operation_completed_count()  { _vm_operation_completed_count++; }
 622 
 623   // For tracking the heavyweight monitor the thread is pending on.
 624   ObjectMonitor* current_pending_monitor() {
 625     return _current_pending_monitor;
 626   }
 627   void set_current_pending_monitor(ObjectMonitor* monitor) {
 628     _current_pending_monitor = monitor;
 629   }
 630   void set_current_pending_monitor_is_from_java(bool from_java) {
 631     _current_pending_monitor_is_from_java = from_java;
 632   }
 633   bool current_pending_monitor_is_from_java() {
 634     return _current_pending_monitor_is_from_java;
 635   }
 636 
 637   // For tracking the ObjectMonitor on which this thread called Object.wait()
 638   ObjectMonitor* current_waiting_monitor() {
 639     return _current_waiting_monitor;
 640   }
 641   void set_current_waiting_monitor(ObjectMonitor* monitor) {
 642     _current_waiting_monitor = monitor;
 643   }
 644 
 645   // GC support
 646   // Apply "f->do_oop" to all root oops in "this".
 647   //   Used by JavaThread::oops_do.
 648   // Apply "cf->do_code_blob" (if !NULL) to all code blobs active in frames
 649   virtual void oops_do(OopClosure* f, CodeBlobClosure* cf);
 650 
 651   // Handles the parallel case for claim_threads_do.
 652  private:
 653   bool claim_par_threads_do(uintx claim_token);
 654  public:
 655   // Requires that "claim_token" is that of the current iteration.
 656   // If "is_par" is false, sets the token of "this" to
 657   // "claim_token", and returns "true".  If "is_par" is true,
 658   // uses an atomic instruction to set the current thread's token to
 659   // "claim_token", if it is not already.  Returns "true" iff the
 660   // calling thread does the update, this indicates that the calling thread
 661   // has claimed the thread in the current iteration.
 662   bool claim_threads_do(bool is_par, uintx claim_token) {
 663     if (!is_par) {
 664       _threads_do_token = claim_token;
 665       return true;
 666     } else {
 667       return claim_par_threads_do(claim_token);
 668     }
 669   }
 670 
 671   uintx threads_do_token() const { return _threads_do_token; }
 672 
 673   // jvmtiRedefineClasses support
 674   void metadata_handles_do(void f(Metadata*));
 675 
 676   // Used by fast lock support
 677   virtual bool is_lock_owned(address adr) const;
 678 
 679   // Check if address is in the stack of the thread (not just for locks).
 680   // Warning: the method can only be used on the running thread
 681   bool is_in_stack(address adr) const;
 682   // Check if address is in the usable part of the stack (excludes protected
 683   // guard pages)
 684   bool is_in_usable_stack(address adr) const;
 685 
 686   // Sets this thread as starting thread. Returns failure if thread
 687   // creation fails due to lack of memory, too many threads etc.
 688   bool set_as_starting_thread();
 689 
 690 protected:
 691   // OS data associated with the thread
 692   OSThread* _osthread;  // Platform-specific thread information
 693 
 694   // Thread local resource area for temporary allocation within the VM
 695   ResourceArea* _resource_area;
 696 
 697   DEBUG_ONLY(ResourceMark* _current_resource_mark;)
 698 
 699   // Thread local handle area for allocation of handles within the VM
 700   HandleArea* _handle_area;
 701   GrowableArray<Metadata*>* _metadata_handles;
 702 
 703   // Support for stack overflow handling, get_thread, etc.
 704   address          _stack_base;
 705   size_t           _stack_size;
 706   int              _lgrp_id;
 707 
 708   volatile void** polling_page_addr() { return &_polling_page; }
 709 
 710  public:
 711   // Stack overflow support
 712   address stack_base() const           { assert(_stack_base != NULL,"Sanity check"); return _stack_base; }
 713   void    set_stack_base(address base) { _stack_base = base; }
 714   size_t  stack_size() const           { return _stack_size; }
 715   void    set_stack_size(size_t size)  { _stack_size = size; }
 716   address stack_end()  const           { return stack_base() - stack_size(); }
 717   void    record_stack_base_and_size();
 718   void    register_thread_stack_with_NMT() NOT_NMT_RETURN;
 719 
 720   bool    on_local_stack(address adr) const {
 721     // QQQ this has knowledge of direction, ought to be a stack method
 722     return (_stack_base >= adr && adr >= stack_end());
 723   }
 724 
 725   int     lgrp_id() const        { return _lgrp_id; }
 726   void    set_lgrp_id(int value) { _lgrp_id = value; }
 727 
 728   // Printing
 729   void print_on(outputStream* st, bool print_extended_info) const;
 730   virtual void print_on(outputStream* st) const { print_on(st, false); }
 731   void print() const;
 732   virtual void print_on_error(outputStream* st, char* buf, int buflen) const;
 733   void print_value_on(outputStream* st) const;
 734 
 735   // Debug-only code
 736 #ifdef ASSERT
 737  private:
 738   // Deadlock detection support for Mutex locks. List of locks own by thread.
 739   Mutex* _owned_locks;
 740   // Mutex::set_owner_implementation is the only place where _owned_locks is modified,
 741   // thus the friendship
 742   friend class Mutex;
 743   friend class Monitor;
 744 
 745  public:
 746   void print_owned_locks_on(outputStream* st) const;
 747   void print_owned_locks() const                 { print_owned_locks_on(tty);    }
 748   Mutex* owned_locks() const                     { return _owned_locks;          }
 749   bool owns_locks() const                        { return owned_locks() != NULL; }
 750 
 751   // Deadlock detection
 752   ResourceMark* current_resource_mark()          { return _current_resource_mark; }
 753   void set_current_resource_mark(ResourceMark* rm) { _current_resource_mark = rm; }
 754 #endif // ASSERT
 755 
 756   // These functions check conditions on a JavaThread before possibly going to a safepoint,
 757   // including NoSafepointVerifier.
 758   void check_for_valid_safepoint_state(bool potential_vm_operation) NOT_DEBUG_RETURN;
 759   void check_possible_safepoint() NOT_DEBUG_RETURN;
 760 
 761  private:
 762   volatile int _jvmti_env_iteration_count;
 763 
 764  public:
 765   void entering_jvmti_env_iteration()            { ++_jvmti_env_iteration_count; }
 766   void leaving_jvmti_env_iteration()             { --_jvmti_env_iteration_count; }
 767   bool is_inside_jvmti_env_iteration()           { return _jvmti_env_iteration_count > 0; }
 768 
 769   // Code generation
 770   static ByteSize exception_file_offset()        { return byte_offset_of(Thread, _exception_file); }
 771   static ByteSize exception_line_offset()        { return byte_offset_of(Thread, _exception_line); }
 772   static ByteSize active_handles_offset()        { return byte_offset_of(Thread, _active_handles); }
 773 
 774   static ByteSize stack_base_offset()            { return byte_offset_of(Thread, _stack_base); }
 775   static ByteSize stack_size_offset()            { return byte_offset_of(Thread, _stack_size); }
 776 
 777   static ByteSize polling_page_offset()          { return byte_offset_of(Thread, _polling_page); }
 778 
 779   static ByteSize tlab_start_offset()            { return byte_offset_of(Thread, _tlab) + ThreadLocalAllocBuffer::start_offset(); }
 780   static ByteSize tlab_end_offset()              { return byte_offset_of(Thread, _tlab) + ThreadLocalAllocBuffer::end_offset(); }
 781   static ByteSize tlab_top_offset()              { return byte_offset_of(Thread, _tlab) + ThreadLocalAllocBuffer::top_offset(); }
 782   static ByteSize tlab_pf_top_offset()           { return byte_offset_of(Thread, _tlab) + ThreadLocalAllocBuffer::pf_top_offset(); }
 783 
 784   static ByteSize allocated_bytes_offset()       { return byte_offset_of(Thread, _allocated_bytes); }
 785 
 786   JFR_ONLY(DEFINE_THREAD_LOCAL_OFFSET_JFR;)
 787 
 788  public:
 789   volatile intptr_t _Stalled;
 790   volatile int _TypeTag;
 791   ParkEvent * _ParkEvent;                     // for synchronized()
 792   ParkEvent * _MuxEvent;                      // for low-level muxAcquire-muxRelease
 793   int NativeSyncRecursion;                    // diagnostic
 794 
 795   volatile int _OnTrap;                       // Resume-at IP delta
 796   jint _hashStateW;                           // Marsaglia Shift-XOR thread-local RNG
 797   jint _hashStateX;                           // thread-specific hashCode generator state
 798   jint _hashStateY;
 799   jint _hashStateZ;
 800 
 801   // Low-level leaf-lock primitives used to implement synchronization
 802   // and native monitor-mutex infrastructure.
 803   // Not for general synchronization use.
 804   static void SpinAcquire(volatile int * Lock, const char * Name);
 805   static void SpinRelease(volatile int * Lock);
 806   static void muxAcquire(volatile intptr_t * Lock, const char * Name);
 807   static void muxAcquireW(volatile intptr_t * Lock, ParkEvent * ev);
 808   static void muxRelease(volatile intptr_t * Lock);
 809 };
 810 
 811 // Inline implementation of Thread::current()
 812 inline Thread* Thread::current() {
 813   Thread* current = current_or_null();
 814   assert(current != NULL, "Thread::current() called on detached thread");
 815   return current;
 816 }
 817 
 818 inline Thread* Thread::current_or_null() {
 819 #ifndef USE_LIBRARY_BASED_TLS_ONLY
 820   return _thr_current;
 821 #else
 822   if (ThreadLocalStorage::is_initialized()) {
 823     return ThreadLocalStorage::thread();
 824   }
 825   return NULL;
 826 #endif
 827 }
 828 
 829 inline Thread* Thread::current_or_null_safe() {
 830   if (ThreadLocalStorage::is_initialized()) {
 831     return ThreadLocalStorage::thread();
 832   }
 833   return NULL;
 834 }
 835 
 836 class NonJavaThread: public Thread {
 837   friend class VMStructs;
 838 
 839   NonJavaThread* volatile _next;
 840 
 841   class List;
 842   static List _the_list;
 843 
 844   void add_to_the_list();
 845   void remove_from_the_list();
 846 
 847  protected:
 848   virtual void pre_run();
 849   virtual void post_run();
 850 
 851  public:
 852   NonJavaThread();
 853   ~NonJavaThread();
 854 
 855   class Iterator;
 856 };
 857 
 858 // Provides iteration over the list of NonJavaThreads.
 859 // List addition occurs in pre_run(), and removal occurs in post_run(),
 860 // so that only live fully-initialized threads can be found in the list.
 861 // Threads created after an iterator is constructed will not be visited
 862 // by the iterator. The scope of an iterator is a critical section; there
 863 // must be no safepoint checks in that scope.
 864 class NonJavaThread::Iterator : public StackObj {
 865   uint _protect_enter;
 866   NonJavaThread* _current;
 867 
 868   // Noncopyable.
 869   Iterator(const Iterator&);
 870   Iterator& operator=(const Iterator&);
 871 
 872 public:
 873   Iterator();
 874   ~Iterator();
 875 
 876   bool end() const { return _current == NULL; }
 877   NonJavaThread* current() const { return _current; }
 878   void step();
 879 };
 880 
 881 // Name support for threads.  non-JavaThread subclasses with multiple
 882 // uniquely named instances should derive from this.
 883 class NamedThread: public NonJavaThread {
 884   friend class VMStructs;
 885   enum {
 886     max_name_len = 64
 887   };
 888  private:
 889   char* _name;
 890   // log JavaThread being processed by oops_do
 891   JavaThread* _processed_thread;
 892   uint _gc_id; // The current GC id when a thread takes part in GC
 893 
 894  public:
 895   NamedThread();
 896   ~NamedThread();
 897   // May only be called once per thread.
 898   void set_name(const char* format, ...)  ATTRIBUTE_PRINTF(2, 3);
 899   virtual bool is_Named_thread() const { return true; }
 900   virtual char* name() const { return _name == NULL ? (char*)"Unknown Thread" : _name; }
 901   JavaThread *processed_thread() { return _processed_thread; }
 902   void set_processed_thread(JavaThread *thread) { _processed_thread = thread; }
 903   virtual void print_on(outputStream* st) const;
 904 
 905   void set_gc_id(uint gc_id) { _gc_id = gc_id; }
 906   uint gc_id() { return _gc_id; }
 907 };
 908 
 909 // Worker threads are named and have an id of an assigned work.
 910 class WorkerThread: public NamedThread {
 911  private:
 912   uint _id;
 913  public:
 914   WorkerThread() : _id(0)               { }
 915   virtual bool is_Worker_thread() const { return true; }
 916 
 917   virtual WorkerThread* as_Worker_thread() const {
 918     assert(is_Worker_thread(), "Dubious cast to WorkerThread*?");
 919     return (WorkerThread*) this;
 920   }
 921 
 922   void set_id(uint work_id)             { _id = work_id; }
 923   uint id() const                       { return _id; }
 924 };
 925 
 926 // A single WatcherThread is used for simulating timer interrupts.
 927 class WatcherThread: public NonJavaThread {
 928   friend class VMStructs;
 929  protected:
 930   virtual void run();
 931 
 932  private:
 933   static WatcherThread* _watcher_thread;
 934 
 935   static bool _startable;
 936   // volatile due to at least one lock-free read
 937   volatile static bool _should_terminate;
 938  public:
 939   enum SomeConstants {
 940     delay_interval = 10                          // interrupt delay in milliseconds
 941   };
 942 
 943   // Constructor
 944   WatcherThread();
 945 
 946   // No destruction allowed
 947   ~WatcherThread() {
 948     guarantee(false, "WatcherThread deletion must fix the race with VM termination");
 949   }
 950 
 951   // Tester
 952   bool is_Watcher_thread() const                 { return true; }
 953 
 954   // Printing
 955   char* name() const { return (char*)"VM Periodic Task Thread"; }
 956   void print_on(outputStream* st) const;
 957   void unpark();
 958 
 959   // Returns the single instance of WatcherThread
 960   static WatcherThread* watcher_thread()         { return _watcher_thread; }
 961 
 962   // Create and start the single instance of WatcherThread, or stop it on shutdown
 963   static void start();
 964   static void stop();
 965   // Only allow start once the VM is sufficiently initialized
 966   // Otherwise the first task to enroll will trigger the start
 967   static void make_startable();
 968  private:
 969   int sleep() const;
 970 };
 971 
 972 
 973 class CompilerThread;
 974 
 975 typedef void (*ThreadFunction)(JavaThread*, TRAPS);
 976 
 977 class JavaThread: public Thread {
 978   friend class VMStructs;
 979   friend class JVMCIVMStructs;
 980   friend class WhiteBox;
 981  private:
 982   bool           _on_thread_list;                // Is set when this JavaThread is added to the Threads list
 983   oop            _threadObj;                     // The Java level thread object
 984 
 985 #ifdef ASSERT
 986  private:
 987   int _java_call_counter;
 988 
 989  public:
 990   int  java_call_counter()                       { return _java_call_counter; }
 991   void inc_java_call_counter()                   { _java_call_counter++; }
 992   void dec_java_call_counter() {
 993     assert(_java_call_counter > 0, "Invalid nesting of JavaCallWrapper");
 994     _java_call_counter--;
 995   }
 996  private:  // restore original namespace restriction
 997 #endif  // ifdef ASSERT
 998 
 999 #ifndef PRODUCT
1000  public:
1001   enum {
1002     jump_ring_buffer_size = 16
1003   };
1004  private:  // restore original namespace restriction
1005 #endif
1006 
1007   JavaFrameAnchor _anchor;                       // Encapsulation of current java frame and it state
1008 
1009   ThreadFunction _entry_point;
1010 
1011   JNIEnv        _jni_environment;
1012 
1013   // Deopt support
1014   DeoptResourceMark*  _deopt_mark;               // Holds special ResourceMark for deoptimization
1015 
1016   CompiledMethod*       _deopt_nmethod;         // CompiledMethod that is currently being deoptimized
1017   vframeArray*  _vframe_array_head;              // Holds the heap of the active vframeArrays
1018   vframeArray*  _vframe_array_last;              // Holds last vFrameArray we popped
1019   // Because deoptimization is lazy we must save jvmti requests to set locals
1020   // in compiled frames until we deoptimize and we have an interpreter frame.
1021   // This holds the pointer to array (yeah like there might be more than one) of
1022   // description of compiled vframes that have locals that need to be updated.
1023   GrowableArray<jvmtiDeferredLocalVariableSet*>* _deferred_locals_updates;
1024 
1025   // Handshake value for fixing 6243940. We need a place for the i2c
1026   // adapter to store the callee Method*. This value is NEVER live
1027   // across a gc point so it does NOT have to be gc'd
1028   // The handshake is open ended since we can't be certain that it will
1029   // be NULLed. This is because we rarely ever see the race and end up
1030   // in handle_wrong_method which is the backend of the handshake. See
1031   // code in i2c adapters and handle_wrong_method.
1032 
1033   Method*       _callee_target;
1034 
1035   // Used to pass back results to the interpreter or generated code running Java code.
1036   oop           _vm_result;    // oop result is GC-preserved
1037   Metadata*     _vm_result_2;  // non-oop result
1038 
1039   // See ReduceInitialCardMarks: this holds the precise space interval of
1040   // the most recent slow path allocation for which compiled code has
1041   // elided card-marks for performance along the fast-path.
1042   MemRegion     _deferred_card_mark;
1043 
1044   MonitorChunk* _monitor_chunks;                 // Contains the off stack monitors
1045                                                  // allocated during deoptimization
1046                                                  // and by JNI_MonitorEnter/Exit
1047 
1048   // Async. requests support
1049   enum AsyncRequests {
1050     _no_async_condition = 0,
1051     _async_exception,
1052     _async_unsafe_access_error
1053   };
1054   AsyncRequests _special_runtime_exit_condition; // Enum indicating pending async. request
1055   oop           _pending_async_exception;
1056 
1057   // Safepoint support
1058  public:                                         // Expose _thread_state for SafeFetchInt()
1059   volatile JavaThreadState _thread_state;
1060  private:
1061   ThreadSafepointState* _safepoint_state;        // Holds information about a thread during a safepoint
1062   address               _saved_exception_pc;     // Saved pc of instruction where last implicit exception happened
1063 
1064   // JavaThread termination support
1065   enum TerminatedTypes {
1066     _not_terminated = 0xDEAD - 2,
1067     _thread_exiting,                             // JavaThread::exit() has been called for this thread
1068     _thread_terminated,                          // JavaThread is removed from thread list
1069     _vm_exited                                   // JavaThread is still executing native code, but VM is terminated
1070                                                  // only VM_Exit can set _vm_exited
1071   };
1072 
1073   // In general a JavaThread's _terminated field transitions as follows:
1074   //
1075   //   _not_terminated => _thread_exiting => _thread_terminated
1076   //
1077   // _vm_exited is a special value to cover the case of a JavaThread
1078   // executing native code after the VM itself is terminated.
1079   volatile TerminatedTypes _terminated;
1080   // suspend/resume support
1081   volatile bool         _suspend_equivalent;     // Suspend equivalent condition
1082   jint                  _in_deopt_handler;       // count of deoptimization
1083                                                  // handlers thread is in
1084   volatile bool         _doing_unsafe_access;    // Thread may fault due to unsafe access
1085   bool                  _do_not_unlock_if_synchronized;  // Do not unlock the receiver of a synchronized method (since it was
1086                                                          // never locked) when throwing an exception. Used by interpreter only.
1087 
1088   // JNI attach states:
1089   enum JNIAttachStates {
1090     _not_attaching_via_jni = 1,  // thread is not attaching via JNI
1091     _attaching_via_jni,          // thread is attaching via JNI
1092     _attached_via_jni            // thread has attached via JNI
1093   };
1094 
1095   // A regular JavaThread's _jni_attach_state is _not_attaching_via_jni.
1096   // A native thread that is attaching via JNI starts with a value
1097   // of _attaching_via_jni and transitions to _attached_via_jni.
1098   volatile JNIAttachStates _jni_attach_state;
1099 
1100  public:
1101   // State of the stack guard pages for this thread.
1102   enum StackGuardState {
1103     stack_guard_unused,         // not needed
1104     stack_guard_reserved_disabled,
1105     stack_guard_yellow_reserved_disabled,// disabled (temporarily) after stack overflow
1106     stack_guard_enabled         // enabled
1107   };
1108 
1109  private:
1110 
1111 #if INCLUDE_JVMCI
1112   // The _pending_* fields below are used to communicate extra information
1113   // from an uncommon trap in JVMCI compiled code to the uncommon trap handler.
1114 
1115   // Communicates the DeoptReason and DeoptAction of the uncommon trap
1116   int       _pending_deoptimization;
1117 
1118   // Specifies whether the uncommon trap is to bci 0 of a synchronized method
1119   // before the monitor has been acquired.
1120   bool      _pending_monitorenter;
1121 
1122   // Specifies if the DeoptReason for the last uncommon trap was Reason_transfer_to_interpreter
1123   bool      _pending_transfer_to_interpreter;
1124 
1125   // True if in a runtime call from compiled code that will deoptimize
1126   // and re-execute a failed heap allocation in the interpreter.
1127   bool      _in_retryable_allocation;
1128 
1129   // An id of a speculation that JVMCI compiled code can use to further describe and
1130   // uniquely identify the  speculative optimization guarded by the uncommon trap
1131   jlong     _pending_failed_speculation;
1132 
1133   // These fields are mutually exclusive in terms of live ranges.
1134   union {
1135     // Communicates the pc at which the most recent implicit exception occurred
1136     // from the signal handler to a deoptimization stub.
1137     address   _implicit_exception_pc;
1138 
1139     // Communicates an alternative call target to an i2c stub from a JavaCall .
1140     address   _alternate_call_target;
1141   } _jvmci;
1142 
1143   // Support for high precision, thread sensitive counters in JVMCI compiled code.
1144   jlong*    _jvmci_counters;
1145 
1146  public:
1147   static jlong* _jvmci_old_thread_counters;
1148   static void collect_counters(jlong* array, int length);
1149 
1150   bool resize_counters(int current_size, int new_size);
1151 
1152   static bool resize_all_jvmci_counters(int new_size);
1153 
1154  private:
1155 #endif // INCLUDE_JVMCI
1156 
1157   StackGuardState  _stack_guard_state;
1158 
1159   // Precompute the limit of the stack as used in stack overflow checks.
1160   // We load it from here to simplify the stack overflow check in assembly.
1161   address          _stack_overflow_limit;
1162   address          _reserved_stack_activation;
1163 
1164   // Compiler exception handling (NOTE: The _exception_oop is *NOT* the same as _pending_exception. It is
1165   // used to temp. parsing values into and out of the runtime system during exception handling for compiled
1166   // code)
1167   volatile oop     _exception_oop;               // Exception thrown in compiled code
1168   volatile address _exception_pc;                // PC where exception happened
1169   volatile address _exception_handler_pc;        // PC for handler of exception
1170   volatile int     _is_method_handle_return;     // true (== 1) if the current exception PC is a MethodHandle call site.
1171 
1172  private:
1173   // support for JNI critical regions
1174   jint    _jni_active_critical;                  // count of entries into JNI critical region
1175 
1176   // Checked JNI: function name requires exception check
1177   char* _pending_jni_exception_check_fn;
1178 
1179   // For deadlock detection.
1180   int _depth_first_number;
1181 
1182   // JVMTI PopFrame support
1183   // This is set to popframe_pending to signal that top Java frame should be popped immediately
1184   int _popframe_condition;
1185 
1186   // If reallocation of scalar replaced objects fails, we throw OOM
1187   // and during exception propagation, pop the top
1188   // _frames_to_pop_failed_realloc frames, the ones that reference
1189   // failed reallocations.
1190   int _frames_to_pop_failed_realloc;
1191 
1192   friend class VMThread;
1193   friend class ThreadWaitTransition;
1194   friend class VM_Exit;
1195 
1196   void initialize();                             // Initialized the instance variables
1197 
1198  public:
1199   // Constructor
1200   JavaThread(bool is_attaching_via_jni = false); // for main thread and JNI attached threads
1201   JavaThread(ThreadFunction entry_point, size_t stack_size = 0);
1202   ~JavaThread();
1203 
1204 #ifdef ASSERT
1205   // verify this JavaThread hasn't be published in the Threads::list yet
1206   void verify_not_published();
1207 #endif // ASSERT
1208 
1209   //JNI functiontable getter/setter for JVMTI jni function table interception API.
1210   void set_jni_functions(struct JNINativeInterface_* functionTable) {
1211     _jni_environment.functions = functionTable;
1212   }
1213   struct JNINativeInterface_* get_jni_functions() {
1214     return (struct JNINativeInterface_ *)_jni_environment.functions;
1215   }
1216 
1217   // This function is called at thread creation to allow
1218   // platform specific thread variables to be initialized.
1219   void cache_global_variables();
1220 
1221   // Executes Shutdown.shutdown()
1222   void invoke_shutdown_hooks();
1223 
1224   // Cleanup on thread exit
1225   enum ExitType {
1226     normal_exit,
1227     jni_detach
1228   };
1229   void exit(bool destroy_vm, ExitType exit_type = normal_exit);
1230 
1231   void cleanup_failed_attach_current_thread(bool is_daemon);
1232 
1233   // Testers
1234   virtual bool is_Java_thread() const            { return true;  }
1235   virtual bool can_call_java() const             { return true; }
1236 
1237   virtual bool is_active_Java_thread() const {
1238     return on_thread_list() && !is_terminated();
1239   }
1240 
1241   // Thread oop. threadObj() can be NULL for initial JavaThread
1242   // (or for threads attached via JNI)
1243   oop threadObj() const                          { return _threadObj; }
1244   void set_threadObj(oop p)                      { _threadObj = p; }
1245 
1246   // Prepare thread and add to priority queue.  If a priority is
1247   // not specified, use the priority of the thread object. Threads_lock
1248   // must be held while this function is called.
1249   void prepare(jobject jni_thread, ThreadPriority prio=NoPriority);
1250 
1251   void set_saved_exception_pc(address pc)        { _saved_exception_pc = pc; }
1252   address saved_exception_pc()                   { return _saved_exception_pc; }
1253 
1254 
1255   ThreadFunction entry_point() const             { return _entry_point; }
1256 
1257   // Allocates a new Java level thread object for this thread. thread_name may be NULL.
1258   void allocate_threadObj(Handle thread_group, const char* thread_name, bool daemon, TRAPS);
1259 
1260   // Last frame anchor routines
1261 
1262   JavaFrameAnchor* frame_anchor(void)            { return &_anchor; }
1263 
1264   // last_Java_sp
1265   bool has_last_Java_frame() const               { return _anchor.has_last_Java_frame(); }
1266   intptr_t* last_Java_sp() const                 { return _anchor.last_Java_sp(); }
1267 
1268   // last_Java_pc
1269 
1270   address last_Java_pc(void)                     { return _anchor.last_Java_pc(); }
1271 
1272   // Safepoint support
1273   inline JavaThreadState thread_state() const;
1274   inline void set_thread_state(JavaThreadState s);
1275   inline void set_thread_state_fence(JavaThreadState s);  // fence after setting thread state
1276   inline ThreadSafepointState* safepoint_state() const;
1277   inline void set_safepoint_state(ThreadSafepointState* state);
1278   inline bool is_at_poll_safepoint();
1279 
1280   // JavaThread termination and lifecycle support:
1281   void smr_delete();
1282   bool on_thread_list() const { return _on_thread_list; }
1283   void set_on_thread_list() { _on_thread_list = true; }
1284 
1285   // thread has called JavaThread::exit() or is terminated
1286   bool is_exiting() const;
1287   // thread is terminated (no longer on the threads list); we compare
1288   // against the two non-terminated values so that a freed JavaThread
1289   // will also be considered terminated.
1290   bool check_is_terminated(TerminatedTypes l_terminated) const {
1291     return l_terminated != _not_terminated && l_terminated != _thread_exiting;
1292   }
1293   bool is_terminated() const;
1294   void set_terminated(TerminatedTypes t);
1295   // special for Threads::remove() which is static:
1296   void set_terminated_value();
1297   void block_if_vm_exited();
1298 
1299   bool doing_unsafe_access()                     { return _doing_unsafe_access; }
1300   void set_doing_unsafe_access(bool val)         { _doing_unsafe_access = val; }
1301 
1302   bool do_not_unlock_if_synchronized()             { return _do_not_unlock_if_synchronized; }
1303   void set_do_not_unlock_if_synchronized(bool val) { _do_not_unlock_if_synchronized = val; }
1304 
1305   inline void set_polling_page_release(void* poll_value);
1306   inline void set_polling_page(void* poll_value);
1307   inline volatile void* get_polling_page();
1308 
1309  private:
1310   // Support for thread handshake operations
1311   HandshakeState _handshake;
1312  public:
1313   void set_handshake_operation(HandshakeOperation* op) {
1314     _handshake.set_operation(this, op);
1315   }
1316 
1317   bool has_handshake() const {
1318     return _handshake.has_operation();
1319   }
1320 
1321   void handshake_process_by_self() {
1322     _handshake.process_by_self(this);
1323   }
1324 
1325   void handshake_process_by_vmthread() {
1326     _handshake.process_by_vmthread(this);
1327   }
1328 
1329   // Suspend/resume support for JavaThread
1330  private:
1331   inline void set_ext_suspended();
1332   inline void clear_ext_suspended();
1333 
1334  public:
1335   void java_suspend(); // higher-level suspension logic called by the public APIs
1336   void java_resume();  // higher-level resume logic called by the public APIs
1337   int  java_suspend_self(); // low-level self-suspension mechanics
1338 
1339  private:
1340   // mid-level wrapper around java_suspend_self to set up correct state and
1341   // check for a pending safepoint at the end
1342   void java_suspend_self_with_safepoint_check();
1343 
1344  public:
1345   void check_and_wait_while_suspended() {
1346     assert(JavaThread::current() == this, "sanity check");
1347 
1348     bool do_self_suspend;
1349     do {
1350       // were we externally suspended while we were waiting?
1351       do_self_suspend = handle_special_suspend_equivalent_condition();
1352       if (do_self_suspend) {
1353         // don't surprise the thread that suspended us by returning
1354         java_suspend_self();
1355         set_suspend_equivalent();
1356       }
1357     } while (do_self_suspend);
1358   }
1359   static void check_safepoint_and_suspend_for_native_trans(JavaThread *thread);
1360   // Check for async exception in addition to safepoint and suspend request.
1361   static void check_special_condition_for_native_trans(JavaThread *thread);
1362 
1363   // Same as check_special_condition_for_native_trans but finishes the
1364   // transition into thread_in_Java mode so that it can potentially
1365   // block.
1366   static void check_special_condition_for_native_trans_and_transition(JavaThread *thread);
1367 
1368   bool is_ext_suspend_completed(bool called_by_wait, int delay, uint32_t *bits);
1369   bool is_ext_suspend_completed_with_lock(uint32_t *bits) {
1370     MutexLocker ml(SR_lock(), Mutex::_no_safepoint_check_flag);
1371     // Warning: is_ext_suspend_completed() may temporarily drop the
1372     // SR_lock to allow the thread to reach a stable thread state if
1373     // it is currently in a transient thread state.
1374     return is_ext_suspend_completed(false /* !called_by_wait */,
1375                                     SuspendRetryDelay, bits);
1376   }
1377 
1378   // We cannot allow wait_for_ext_suspend_completion() to run forever or
1379   // we could hang. SuspendRetryCount and SuspendRetryDelay are normally
1380   // passed as the count and delay parameters. Experiments with specific
1381   // calls to wait_for_ext_suspend_completion() can be done by passing
1382   // other values in the code. Experiments with all calls can be done
1383   // via the appropriate -XX options.
1384   bool wait_for_ext_suspend_completion(int count, int delay, uint32_t *bits);
1385 
1386   // test for suspend - most (all?) of these should go away
1387   bool is_thread_fully_suspended(bool wait_for_suspend, uint32_t *bits);
1388 
1389   inline void set_external_suspend();
1390   inline void clear_external_suspend();
1391 
1392   bool is_external_suspend() const {
1393     return (_suspend_flags & _external_suspend) != 0;
1394   }
1395   // Whenever a thread transitions from native to vm/java it must suspend
1396   // if external|deopt suspend is present.
1397   bool is_suspend_after_native() const {
1398     return (_suspend_flags & (_external_suspend JFR_ONLY(| _trace_flag))) != 0;
1399   }
1400 
1401   // external suspend request is completed
1402   bool is_ext_suspended() const {
1403     return (_suspend_flags & _ext_suspended) != 0;
1404   }
1405 
1406   bool is_external_suspend_with_lock() const {
1407     MutexLocker ml(SR_lock(), Mutex::_no_safepoint_check_flag);
1408     return is_external_suspend();
1409   }
1410 
1411   // Special method to handle a pending external suspend request
1412   // when a suspend equivalent condition lifts.
1413   bool handle_special_suspend_equivalent_condition() {
1414     assert(is_suspend_equivalent(),
1415            "should only be called in a suspend equivalence condition");
1416     MutexLocker ml(SR_lock(), Mutex::_no_safepoint_check_flag);
1417     bool ret = is_external_suspend();
1418     if (!ret) {
1419       // not about to self-suspend so clear suspend equivalence
1420       clear_suspend_equivalent();
1421     }
1422     // implied else:
1423     // We have a pending external suspend request so we leave the
1424     // suspend_equivalent flag set until java_suspend_self() sets
1425     // the ext_suspended flag and clears the suspend_equivalent
1426     // flag. This insures that wait_for_ext_suspend_completion()
1427     // will return consistent values.
1428     return ret;
1429   }
1430 
1431   // utility methods to see if we are doing some kind of suspension
1432   bool is_being_ext_suspended() const            {
1433     MutexLocker ml(SR_lock(), Mutex::_no_safepoint_check_flag);
1434     return is_ext_suspended() || is_external_suspend();
1435   }
1436 
1437   bool is_suspend_equivalent() const             { return _suspend_equivalent; }
1438 
1439   void set_suspend_equivalent()                  { _suspend_equivalent = true; }
1440   void clear_suspend_equivalent()                { _suspend_equivalent = false; }
1441 
1442   // Thread.stop support
1443   void send_thread_stop(oop throwable);
1444   AsyncRequests clear_special_runtime_exit_condition() {
1445     AsyncRequests x = _special_runtime_exit_condition;
1446     _special_runtime_exit_condition = _no_async_condition;
1447     return x;
1448   }
1449 
1450   // Are any async conditions present?
1451   bool has_async_condition() { return (_special_runtime_exit_condition != _no_async_condition); }
1452 
1453   void check_and_handle_async_exceptions(bool check_unsafe_error = true);
1454 
1455   // these next two are also used for self-suspension and async exception support
1456   void handle_special_runtime_exit_condition(bool check_asyncs = true);
1457 
1458   // Return true if JavaThread has an asynchronous condition or
1459   // if external suspension is requested.
1460   bool has_special_runtime_exit_condition() {
1461     // Because we don't use is_external_suspend_with_lock
1462     // it is possible that we won't see an asynchronous external suspend
1463     // request that has just gotten started, i.e., SR_lock grabbed but
1464     // _external_suspend field change either not made yet or not visible
1465     // yet. However, this is okay because the request is asynchronous and
1466     // we will see the new flag value the next time through. It's also
1467     // possible that the external suspend request is dropped after
1468     // we have checked is_external_suspend(), we will recheck its value
1469     // under SR_lock in java_suspend_self().
1470     return (_special_runtime_exit_condition != _no_async_condition) ||
1471             is_external_suspend() || is_trace_suspend();
1472   }
1473 
1474   void set_pending_unsafe_access_error()          { _special_runtime_exit_condition = _async_unsafe_access_error; }
1475 
1476   inline void set_pending_async_exception(oop e);
1477 
1478   // Fast-locking support
1479   bool is_lock_owned(address adr) const;
1480 
1481   // Accessors for vframe array top
1482   // The linked list of vframe arrays are sorted on sp. This means when we
1483   // unpack the head must contain the vframe array to unpack.
1484   void set_vframe_array_head(vframeArray* value) { _vframe_array_head = value; }
1485   vframeArray* vframe_array_head() const         { return _vframe_array_head;  }
1486 
1487   // Side structure for deferring update of java frame locals until deopt occurs
1488   GrowableArray<jvmtiDeferredLocalVariableSet*>* deferred_locals() const { return _deferred_locals_updates; }
1489   void set_deferred_locals(GrowableArray<jvmtiDeferredLocalVariableSet *>* vf) { _deferred_locals_updates = vf; }
1490 
1491   // These only really exist to make debugging deopt problems simpler
1492 
1493   void set_vframe_array_last(vframeArray* value) { _vframe_array_last = value; }
1494   vframeArray* vframe_array_last() const         { return _vframe_array_last;  }
1495 
1496   // The special resourceMark used during deoptimization
1497 
1498   void set_deopt_mark(DeoptResourceMark* value)  { _deopt_mark = value; }
1499   DeoptResourceMark* deopt_mark(void)            { return _deopt_mark; }
1500 
1501   void set_deopt_compiled_method(CompiledMethod* nm)  { _deopt_nmethod = nm; }
1502   CompiledMethod* deopt_compiled_method()        { return _deopt_nmethod; }
1503 
1504   Method*    callee_target() const               { return _callee_target; }
1505   void set_callee_target  (Method* x)          { _callee_target   = x; }
1506 
1507   // Oop results of vm runtime calls
1508   oop  vm_result() const                         { return _vm_result; }
1509   void set_vm_result  (oop x)                    { _vm_result   = x; }
1510 
1511   Metadata*    vm_result_2() const               { return _vm_result_2; }
1512   void set_vm_result_2  (Metadata* x)          { _vm_result_2   = x; }
1513 
1514   MemRegion deferred_card_mark() const           { return _deferred_card_mark; }
1515   void set_deferred_card_mark(MemRegion mr)      { _deferred_card_mark = mr;   }
1516 
1517 #if INCLUDE_JVMCI
1518   int  pending_deoptimization() const             { return _pending_deoptimization; }
1519   jlong pending_failed_speculation() const        { return _pending_failed_speculation; }
1520   bool has_pending_monitorenter() const           { return _pending_monitorenter; }
1521   void set_pending_monitorenter(bool b)           { _pending_monitorenter = b; }
1522   void set_pending_deoptimization(int reason)     { _pending_deoptimization = reason; }
1523   void set_pending_failed_speculation(jlong failed_speculation) { _pending_failed_speculation = failed_speculation; }
1524   void set_pending_transfer_to_interpreter(bool b) { _pending_transfer_to_interpreter = b; }
1525   void set_jvmci_alternate_call_target(address a) { assert(_jvmci._alternate_call_target == NULL, "must be"); _jvmci._alternate_call_target = a; }
1526   void set_jvmci_implicit_exception_pc(address a) { assert(_jvmci._implicit_exception_pc == NULL, "must be"); _jvmci._implicit_exception_pc = a; }
1527 
1528   virtual bool in_retryable_allocation() const    { return _in_retryable_allocation; }
1529   void set_in_retryable_allocation(bool b)        { _in_retryable_allocation = b; }
1530 #endif // INCLUDE_JVMCI
1531 
1532   // Exception handling for compiled methods
1533   oop      exception_oop() const                 { return _exception_oop; }
1534   address  exception_pc() const                  { return _exception_pc; }
1535   address  exception_handler_pc() const          { return _exception_handler_pc; }
1536   bool     is_method_handle_return() const       { return _is_method_handle_return == 1; }
1537 
1538   void set_exception_oop(oop o)                  { (void)const_cast<oop&>(_exception_oop = o); }
1539   void set_exception_pc(address a)               { _exception_pc = a; }
1540   void set_exception_handler_pc(address a)       { _exception_handler_pc = a; }
1541   void set_is_method_handle_return(bool value)   { _is_method_handle_return = value ? 1 : 0; }
1542 
1543   void clear_exception_oop_and_pc() {
1544     set_exception_oop(NULL);
1545     set_exception_pc(NULL);
1546   }
1547 
1548   // Stack overflow support
1549   //
1550   //  (small addresses)
1551   //
1552   //  --  <-- stack_end()                   ---
1553   //  |                                      |
1554   //  |  red pages                           |
1555   //  |                                      |
1556   //  --  <-- stack_red_zone_base()          |
1557   //  |                                      |
1558   //  |                                     guard
1559   //  |  yellow pages                       zone
1560   //  |                                      |
1561   //  |                                      |
1562   //  --  <-- stack_yellow_zone_base()       |
1563   //  |                                      |
1564   //  |                                      |
1565   //  |  reserved pages                      |
1566   //  |                                      |
1567   //  --  <-- stack_reserved_zone_base()    ---      ---
1568   //                                                 /|\  shadow     <--  stack_overflow_limit() (somewhere in here)
1569   //                                                  |   zone
1570   //                                                 \|/  size
1571   //  some untouched memory                          ---
1572   //
1573   //
1574   //  --
1575   //  |
1576   //  |  shadow zone
1577   //  |
1578   //  --
1579   //  x    frame n
1580   //  --
1581   //  x    frame n-1
1582   //  x
1583   //  --
1584   //  ...
1585   //
1586   //  --
1587   //  x    frame 0
1588   //  --  <-- stack_base()
1589   //
1590   //  (large addresses)
1591   //
1592 
1593  private:
1594   // These values are derived from flags StackRedPages, StackYellowPages,
1595   // StackReservedPages and StackShadowPages. The zone size is determined
1596   // ergonomically if page_size > 4K.
1597   static size_t _stack_red_zone_size;
1598   static size_t _stack_yellow_zone_size;
1599   static size_t _stack_reserved_zone_size;
1600   static size_t _stack_shadow_zone_size;
1601  public:
1602   inline size_t stack_available(address cur_sp);
1603 
1604   static size_t stack_red_zone_size() {
1605     assert(_stack_red_zone_size > 0, "Don't call this before the field is initialized.");
1606     return _stack_red_zone_size;
1607   }
1608   static void set_stack_red_zone_size(size_t s) {
1609     assert(is_aligned(s, os::vm_page_size()),
1610            "We can not protect if the red zone size is not page aligned.");
1611     assert(_stack_red_zone_size == 0, "This should be called only once.");
1612     _stack_red_zone_size = s;
1613   }
1614   address stack_red_zone_base() {
1615     return (address)(stack_end() + stack_red_zone_size());
1616   }
1617   bool in_stack_red_zone(address a) {
1618     return a <= stack_red_zone_base() && a >= stack_end();
1619   }
1620 
1621   static size_t stack_yellow_zone_size() {
1622     assert(_stack_yellow_zone_size > 0, "Don't call this before the field is initialized.");
1623     return _stack_yellow_zone_size;
1624   }
1625   static void set_stack_yellow_zone_size(size_t s) {
1626     assert(is_aligned(s, os::vm_page_size()),
1627            "We can not protect if the yellow zone size is not page aligned.");
1628     assert(_stack_yellow_zone_size == 0, "This should be called only once.");
1629     _stack_yellow_zone_size = s;
1630   }
1631 
1632   static size_t stack_reserved_zone_size() {
1633     // _stack_reserved_zone_size may be 0. This indicates the feature is off.
1634     return _stack_reserved_zone_size;
1635   }
1636   static void set_stack_reserved_zone_size(size_t s) {
1637     assert(is_aligned(s, os::vm_page_size()),
1638            "We can not protect if the reserved zone size is not page aligned.");
1639     assert(_stack_reserved_zone_size == 0, "This should be called only once.");
1640     _stack_reserved_zone_size = s;
1641   }
1642   address stack_reserved_zone_base() {
1643     return (address)(stack_end() +
1644                      (stack_red_zone_size() + stack_yellow_zone_size() + stack_reserved_zone_size()));
1645   }
1646   bool in_stack_reserved_zone(address a) {
1647     return (a <= stack_reserved_zone_base()) &&
1648            (a >= (address)((intptr_t)stack_reserved_zone_base() - stack_reserved_zone_size()));
1649   }
1650 
1651   static size_t stack_yellow_reserved_zone_size() {
1652     return _stack_yellow_zone_size + _stack_reserved_zone_size;
1653   }
1654   bool in_stack_yellow_reserved_zone(address a) {
1655     return (a <= stack_reserved_zone_base()) && (a >= stack_red_zone_base());
1656   }
1657 
1658   // Size of red + yellow + reserved zones.
1659   static size_t stack_guard_zone_size() {
1660     return stack_red_zone_size() + stack_yellow_reserved_zone_size();
1661   }
1662 
1663   static size_t stack_shadow_zone_size() {
1664     assert(_stack_shadow_zone_size > 0, "Don't call this before the field is initialized.");
1665     return _stack_shadow_zone_size;
1666   }
1667   static void set_stack_shadow_zone_size(size_t s) {
1668     // The shadow area is not allocated or protected, so
1669     // it needs not be page aligned.
1670     // But the stack bang currently assumes that it is a
1671     // multiple of page size. This guarantees that the bang
1672     // loop touches all pages in the shadow zone.
1673     // This can be guaranteed differently, as well.  E.g., if
1674     // the page size is a multiple of 4K, banging in 4K steps
1675     // suffices to touch all pages. (Some pages are banged
1676     // several times, though.)
1677     assert(is_aligned(s, os::vm_page_size()),
1678            "Stack bang assumes multiple of page size.");
1679     assert(_stack_shadow_zone_size == 0, "This should be called only once.");
1680     _stack_shadow_zone_size = s;
1681   }
1682 
1683   void create_stack_guard_pages();
1684   void remove_stack_guard_pages();
1685 
1686   void enable_stack_reserved_zone();
1687   void disable_stack_reserved_zone();
1688   void enable_stack_yellow_reserved_zone();
1689   void disable_stack_yellow_reserved_zone();
1690   void enable_stack_red_zone();
1691   void disable_stack_red_zone();
1692 
1693   inline bool stack_guard_zone_unused();
1694   inline bool stack_yellow_reserved_zone_disabled();
1695   inline bool stack_reserved_zone_disabled();
1696   inline bool stack_guards_enabled();
1697 
1698   address reserved_stack_activation() const { return _reserved_stack_activation; }
1699   void set_reserved_stack_activation(address addr) {
1700     assert(_reserved_stack_activation == stack_base()
1701             || _reserved_stack_activation == NULL
1702             || addr == stack_base(), "Must not be set twice");
1703     _reserved_stack_activation = addr;
1704   }
1705 
1706   // Attempt to reguard the stack after a stack overflow may have occurred.
1707   // Returns true if (a) guard pages are not needed on this thread, (b) the
1708   // pages are already guarded, or (c) the pages were successfully reguarded.
1709   // Returns false if there is not enough stack space to reguard the pages, in
1710   // which case the caller should unwind a frame and try again.  The argument
1711   // should be the caller's (approximate) sp.
1712   bool reguard_stack(address cur_sp);
1713   // Similar to above but see if current stackpoint is out of the guard area
1714   // and reguard if possible.
1715   bool reguard_stack(void);
1716 
1717   address stack_overflow_limit() { return _stack_overflow_limit; }
1718   void set_stack_overflow_limit() {
1719     _stack_overflow_limit =
1720       stack_end() + MAX2(JavaThread::stack_guard_zone_size(), JavaThread::stack_shadow_zone_size());
1721   }
1722 
1723   // Misc. accessors/mutators
1724   void set_do_not_unlock(void)                   { _do_not_unlock_if_synchronized = true; }
1725   void clr_do_not_unlock(void)                   { _do_not_unlock_if_synchronized = false; }
1726   bool do_not_unlock(void)                       { return _do_not_unlock_if_synchronized; }
1727 
1728   // For assembly stub generation
1729   static ByteSize threadObj_offset()             { return byte_offset_of(JavaThread, _threadObj); }
1730   static ByteSize jni_environment_offset()       { return byte_offset_of(JavaThread, _jni_environment); }
1731   static ByteSize pending_jni_exception_check_fn_offset() {
1732     return byte_offset_of(JavaThread, _pending_jni_exception_check_fn);
1733   }
1734   static ByteSize last_Java_sp_offset() {
1735     return byte_offset_of(JavaThread, _anchor) + JavaFrameAnchor::last_Java_sp_offset();
1736   }
1737   static ByteSize last_Java_pc_offset() {
1738     return byte_offset_of(JavaThread, _anchor) + JavaFrameAnchor::last_Java_pc_offset();
1739   }
1740   static ByteSize frame_anchor_offset() {
1741     return byte_offset_of(JavaThread, _anchor);
1742   }
1743   static ByteSize callee_target_offset()         { return byte_offset_of(JavaThread, _callee_target); }
1744   static ByteSize vm_result_offset()             { return byte_offset_of(JavaThread, _vm_result); }
1745   static ByteSize vm_result_2_offset()           { return byte_offset_of(JavaThread, _vm_result_2); }
1746   static ByteSize thread_state_offset()          { return byte_offset_of(JavaThread, _thread_state); }
1747   static ByteSize saved_exception_pc_offset()    { return byte_offset_of(JavaThread, _saved_exception_pc); }
1748   static ByteSize osthread_offset()              { return byte_offset_of(JavaThread, _osthread); }
1749 #if INCLUDE_JVMCI
1750   static ByteSize pending_deoptimization_offset() { return byte_offset_of(JavaThread, _pending_deoptimization); }
1751   static ByteSize pending_monitorenter_offset()  { return byte_offset_of(JavaThread, _pending_monitorenter); }
1752   static ByteSize pending_failed_speculation_offset() { return byte_offset_of(JavaThread, _pending_failed_speculation); }
1753   static ByteSize jvmci_alternate_call_target_offset() { return byte_offset_of(JavaThread, _jvmci._alternate_call_target); }
1754   static ByteSize jvmci_implicit_exception_pc_offset() { return byte_offset_of(JavaThread, _jvmci._implicit_exception_pc); }
1755   static ByteSize jvmci_counters_offset()        { return byte_offset_of(JavaThread, _jvmci_counters); }
1756 #endif // INCLUDE_JVMCI
1757   static ByteSize exception_oop_offset()         { return byte_offset_of(JavaThread, _exception_oop); }
1758   static ByteSize exception_pc_offset()          { return byte_offset_of(JavaThread, _exception_pc); }
1759   static ByteSize exception_handler_pc_offset()  { return byte_offset_of(JavaThread, _exception_handler_pc); }
1760   static ByteSize stack_overflow_limit_offset()  { return byte_offset_of(JavaThread, _stack_overflow_limit); }
1761   static ByteSize is_method_handle_return_offset() { return byte_offset_of(JavaThread, _is_method_handle_return); }
1762   static ByteSize stack_guard_state_offset()     { return byte_offset_of(JavaThread, _stack_guard_state); }
1763   static ByteSize reserved_stack_activation_offset() { return byte_offset_of(JavaThread, _reserved_stack_activation); }
1764   static ByteSize suspend_flags_offset()         { return byte_offset_of(JavaThread, _suspend_flags); }
1765 
1766   static ByteSize do_not_unlock_if_synchronized_offset() { return byte_offset_of(JavaThread, _do_not_unlock_if_synchronized); }
1767   static ByteSize should_post_on_exceptions_flag_offset() {
1768     return byte_offset_of(JavaThread, _should_post_on_exceptions_flag);
1769   }
1770   static ByteSize doing_unsafe_access_offset() { return byte_offset_of(JavaThread, _doing_unsafe_access); }
1771 
1772   // Returns the jni environment for this thread
1773   JNIEnv* jni_environment()                      { return &_jni_environment; }
1774 
1775   static JavaThread* thread_from_jni_environment(JNIEnv* env) {
1776     JavaThread *thread_from_jni_env = (JavaThread*)((intptr_t)env - in_bytes(jni_environment_offset()));
1777     // Only return NULL if thread is off the thread list; starting to
1778     // exit should not return NULL.
1779     if (thread_from_jni_env->is_terminated()) {
1780       thread_from_jni_env->block_if_vm_exited();
1781       return NULL;
1782     } else {
1783       return thread_from_jni_env;
1784     }
1785   }
1786 
1787   // JNI critical regions. These can nest.
1788   bool in_critical()    { return _jni_active_critical > 0; }
1789   bool in_last_critical()  { return _jni_active_critical == 1; }
1790   inline void enter_critical();
1791   void exit_critical() {
1792     assert(Thread::current() == this, "this must be current thread");
1793     _jni_active_critical--;
1794     assert(_jni_active_critical >= 0, "JNI critical nesting problem?");
1795   }
1796 
1797   // Checked JNI: is the programmer required to check for exceptions, if so specify
1798   // which function name. Returning to a Java frame should implicitly clear the
1799   // pending check, this is done for Native->Java transitions (i.e. user JNI code).
1800   // VM->Java transistions are not cleared, it is expected that JNI code enclosed
1801   // within ThreadToNativeFromVM makes proper exception checks (i.e. VM internal).
1802   bool is_pending_jni_exception_check() const { return _pending_jni_exception_check_fn != NULL; }
1803   void clear_pending_jni_exception_check() { _pending_jni_exception_check_fn = NULL; }
1804   const char* get_pending_jni_exception_check() const { return _pending_jni_exception_check_fn; }
1805   void set_pending_jni_exception_check(const char* fn_name) { _pending_jni_exception_check_fn = (char*) fn_name; }
1806 
1807   // For deadlock detection
1808   int depth_first_number() { return _depth_first_number; }
1809   void set_depth_first_number(int dfn) { _depth_first_number = dfn; }
1810 
1811  private:
1812   void set_monitor_chunks(MonitorChunk* monitor_chunks) { _monitor_chunks = monitor_chunks; }
1813 
1814  public:
1815   MonitorChunk* monitor_chunks() const           { return _monitor_chunks; }
1816   void add_monitor_chunk(MonitorChunk* chunk);
1817   void remove_monitor_chunk(MonitorChunk* chunk);
1818   bool in_deopt_handler() const                  { return _in_deopt_handler > 0; }
1819   void inc_in_deopt_handler()                    { _in_deopt_handler++; }
1820   void dec_in_deopt_handler() {
1821     assert(_in_deopt_handler > 0, "mismatched deopt nesting");
1822     if (_in_deopt_handler > 0) { // robustness
1823       _in_deopt_handler--;
1824     }
1825   }
1826 
1827  private:
1828   void set_entry_point(ThreadFunction entry_point) { _entry_point = entry_point; }
1829 
1830  public:
1831 
1832   // Frame iteration; calls the function f for all frames on the stack
1833   void frames_do(void f(frame*, const RegisterMap*));
1834 
1835   // Memory operations
1836   void oops_do(OopClosure* f, CodeBlobClosure* cf);
1837 
1838   // Sweeper operations
1839   virtual void nmethods_do(CodeBlobClosure* cf);
1840 
1841   // RedefineClasses Support
1842   void metadata_do(MetadataClosure* f);
1843 
1844   // Debug method asserting thread states are correct during a handshake operation.
1845   DEBUG_ONLY(void verify_states_for_handshake();)
1846 
1847   // Misc. operations
1848   char* name() const { return (char*)get_thread_name(); }
1849   void print_on(outputStream* st, bool print_extended_info) const;
1850   void print_on(outputStream* st) const { print_on(st, false); }
1851   void print() const;
1852   void print_thread_state_on(outputStream*) const      PRODUCT_RETURN;
1853   void print_on_error(outputStream* st, char* buf, int buflen) const;
1854   void print_name_on_error(outputStream* st, char* buf, int buflen) const;
1855   void verify();
1856   const char* get_thread_name() const;
1857  protected:
1858   // factor out low-level mechanics for use in both normal and error cases
1859   virtual const char* get_thread_name_string(char* buf = NULL, int buflen = 0) const;
1860  public:
1861   // Accessing frames
1862   frame last_frame() {
1863     _anchor.make_walkable(this);
1864     return pd_last_frame();
1865   }
1866   javaVFrame* last_java_vframe(RegisterMap* reg_map);
1867 
1868   // Returns method at 'depth' java or native frames down the stack
1869   // Used for security checks
1870   Klass* security_get_caller_class(int depth);
1871 
1872   // Print stack trace in external format
1873   void print_stack_on(outputStream* st);
1874   void print_stack() { print_stack_on(tty); }
1875 
1876   // Print stack traces in various internal formats
1877   void trace_stack()                             PRODUCT_RETURN;
1878   void trace_stack_from(vframe* start_vf)        PRODUCT_RETURN;
1879   void trace_frames()                            PRODUCT_RETURN;
1880 
1881   // Print an annotated view of the stack frames
1882   void print_frame_layout(int depth = 0, bool validate_only = false) NOT_DEBUG_RETURN;
1883   void validate_frame_layout() {
1884     print_frame_layout(0, true);
1885   }
1886 
1887   // Function for testing deoptimization
1888   void deoptimize();
1889   void make_zombies();
1890 
1891   void deoptimize_marked_methods();
1892 
1893  public:
1894   // Returns the running thread as a JavaThread
1895   static inline JavaThread* current();
1896 
1897   // Returns the active Java thread.  Do not use this if you know you are calling
1898   // from a JavaThread, as it's slower than JavaThread::current.  If called from
1899   // the VMThread, it also returns the JavaThread that instigated the VMThread's
1900   // operation.  You may not want that either.
1901   static JavaThread* active();
1902 
1903   inline CompilerThread* as_CompilerThread();
1904 
1905  protected:
1906   virtual void pre_run();
1907   virtual void run();
1908   void thread_main_inner();
1909   virtual void post_run();
1910 
1911 
1912  private:
1913   GrowableArray<oop>* _array_for_gc;
1914  public:
1915 
1916   void register_array_for_gc(GrowableArray<oop>* array) { _array_for_gc = array; }
1917 
1918  public:
1919   // Thread local information maintained by JVMTI.
1920   void set_jvmti_thread_state(JvmtiThreadState *value)                           { _jvmti_thread_state = value; }
1921   // A JvmtiThreadState is lazily allocated. This jvmti_thread_state()
1922   // getter is used to get this JavaThread's JvmtiThreadState if it has
1923   // one which means NULL can be returned. JvmtiThreadState::state_for()
1924   // is used to get the specified JavaThread's JvmtiThreadState if it has
1925   // one or it allocates a new JvmtiThreadState for the JavaThread and
1926   // returns it. JvmtiThreadState::state_for() will return NULL only if
1927   // the specified JavaThread is exiting.
1928   JvmtiThreadState *jvmti_thread_state() const                                   { return _jvmti_thread_state; }
1929   static ByteSize jvmti_thread_state_offset()                                    { return byte_offset_of(JavaThread, _jvmti_thread_state); }
1930 
1931   // JVMTI PopFrame support
1932   // Setting and clearing popframe_condition
1933   // All of these enumerated values are bits. popframe_pending
1934   // indicates that a PopFrame() has been requested and not yet been
1935   // completed. popframe_processing indicates that that PopFrame() is in
1936   // the process of being completed. popframe_force_deopt_reexecution_bit
1937   // indicates that special handling is required when returning to a
1938   // deoptimized caller.
1939   enum PopCondition {
1940     popframe_inactive                      = 0x00,
1941     popframe_pending_bit                   = 0x01,
1942     popframe_processing_bit                = 0x02,
1943     popframe_force_deopt_reexecution_bit   = 0x04
1944   };
1945   PopCondition popframe_condition()                   { return (PopCondition) _popframe_condition; }
1946   void set_popframe_condition(PopCondition c)         { _popframe_condition = c; }
1947   void set_popframe_condition_bit(PopCondition c)     { _popframe_condition |= c; }
1948   void clear_popframe_condition()                     { _popframe_condition = popframe_inactive; }
1949   static ByteSize popframe_condition_offset()         { return byte_offset_of(JavaThread, _popframe_condition); }
1950   bool has_pending_popframe()                         { return (popframe_condition() & popframe_pending_bit) != 0; }
1951   bool popframe_forcing_deopt_reexecution()           { return (popframe_condition() & popframe_force_deopt_reexecution_bit) != 0; }
1952   void clear_popframe_forcing_deopt_reexecution()     { _popframe_condition &= ~popframe_force_deopt_reexecution_bit; }
1953 #ifdef CC_INTERP
1954   bool pop_frame_pending(void)                        { return ((_popframe_condition & popframe_pending_bit) != 0); }
1955   void clr_pop_frame_pending(void)                    { _popframe_condition = popframe_inactive; }
1956   bool pop_frame_in_process(void)                     { return ((_popframe_condition & popframe_processing_bit) != 0); }
1957   void set_pop_frame_in_process(void)                 { _popframe_condition |= popframe_processing_bit; }
1958   void clr_pop_frame_in_process(void)                 { _popframe_condition &= ~popframe_processing_bit; }
1959 #endif
1960 
1961   int frames_to_pop_failed_realloc() const            { return _frames_to_pop_failed_realloc; }
1962   void set_frames_to_pop_failed_realloc(int nb)       { _frames_to_pop_failed_realloc = nb; }
1963   void dec_frames_to_pop_failed_realloc()             { _frames_to_pop_failed_realloc--; }
1964 
1965  private:
1966   // Saved incoming arguments to popped frame.
1967   // Used only when popped interpreted frame returns to deoptimized frame.
1968   void*    _popframe_preserved_args;
1969   int      _popframe_preserved_args_size;
1970 
1971  public:
1972   void  popframe_preserve_args(ByteSize size_in_bytes, void* start);
1973   void* popframe_preserved_args();
1974   ByteSize popframe_preserved_args_size();
1975   WordSize popframe_preserved_args_size_in_words();
1976   void  popframe_free_preserved_args();
1977 
1978 
1979  private:
1980   JvmtiThreadState *_jvmti_thread_state;
1981 
1982   // Used by the interpreter in fullspeed mode for frame pop, method
1983   // entry, method exit and single stepping support. This field is
1984   // only set to non-zero by the VM_EnterInterpOnlyMode VM operation.
1985   // It can be set to zero asynchronously (i.e., without a VM operation
1986   // or a lock) so we have to be very careful.
1987   int               _interp_only_mode;
1988 
1989  public:
1990   // used by the interpreter for fullspeed debugging support (see above)
1991   static ByteSize interp_only_mode_offset() { return byte_offset_of(JavaThread, _interp_only_mode); }
1992   bool is_interp_only_mode()                { return (_interp_only_mode != 0); }
1993   int get_interp_only_mode()                { return _interp_only_mode; }
1994   void increment_interp_only_mode()         { ++_interp_only_mode; }
1995   void decrement_interp_only_mode()         { --_interp_only_mode; }
1996 
1997   // support for cached flag that indicates whether exceptions need to be posted for this thread
1998   // if this is false, we can avoid deoptimizing when events are thrown
1999   // this gets set to reflect whether jvmtiExport::post_exception_throw would actually do anything
2000  private:
2001   int    _should_post_on_exceptions_flag;
2002 
2003  public:
2004   int   should_post_on_exceptions_flag()  { return _should_post_on_exceptions_flag; }
2005   void  set_should_post_on_exceptions_flag(int val)  { _should_post_on_exceptions_flag = val; }
2006 
2007  private:
2008   ThreadStatistics *_thread_stat;
2009 
2010  public:
2011   ThreadStatistics* get_thread_stat() const    { return _thread_stat; }
2012 
2013   // Return a blocker object for which this thread is blocked parking.
2014   oop current_park_blocker();
2015 
2016  private:
2017   static size_t _stack_size_at_create;
2018 
2019  public:
2020   static inline size_t stack_size_at_create(void) {
2021     return _stack_size_at_create;
2022   }
2023   static inline void set_stack_size_at_create(size_t value) {
2024     _stack_size_at_create = value;
2025   }
2026 
2027   // Machine dependent stuff
2028 #include OS_CPU_HEADER(thread)
2029 
2030   // JSR166 per-thread parker
2031  private:
2032   Parker*    _parker;
2033  public:
2034   Parker*     parker() { return _parker; }
2035 
2036   // Biased locking support
2037  private:
2038   GrowableArray<MonitorInfo*>* _cached_monitor_info;
2039  public:
2040   GrowableArray<MonitorInfo*>* cached_monitor_info() { return _cached_monitor_info; }
2041   void set_cached_monitor_info(GrowableArray<MonitorInfo*>* info) { _cached_monitor_info = info; }
2042 
2043   // clearing/querying jni attach status
2044   bool is_attaching_via_jni() const { return _jni_attach_state == _attaching_via_jni; }
2045   bool has_attached_via_jni() const { return is_attaching_via_jni() || _jni_attach_state == _attached_via_jni; }
2046   inline void set_done_attaching_via_jni();
2047 
2048   // Stack dump assistance:
2049   // Track the class we want to initialize but for which we have to wait
2050   // on its init_lock() because it is already being initialized.
2051   void set_class_to_be_initialized(InstanceKlass* k);
2052   InstanceKlass* class_to_be_initialized() const;
2053 
2054 private:
2055   InstanceKlass* _class_to_be_initialized;
2056 
2057   // java.lang.Thread.sleep support
2058 public:
2059   ParkEvent * _SleepEvent;
2060   bool sleep(jlong millis);
2061 };
2062 
2063 // Inline implementation of JavaThread::current
2064 inline JavaThread* JavaThread::current() {
2065   Thread* thread = Thread::current();
2066   assert(thread->is_Java_thread(), "just checking");
2067   return (JavaThread*)thread;
2068 }
2069 
2070 inline CompilerThread* JavaThread::as_CompilerThread() {
2071   assert(is_Compiler_thread(), "just checking");
2072   return (CompilerThread*)this;
2073 }
2074 
2075 // Dedicated thread to sweep the code cache
2076 class CodeCacheSweeperThread : public JavaThread {
2077   CompiledMethod*       _scanned_compiled_method; // nmethod being scanned by the sweeper
2078  public:
2079   CodeCacheSweeperThread();
2080   // Track the nmethod currently being scanned by the sweeper
2081   void set_scanned_compiled_method(CompiledMethod* cm) {
2082     assert(_scanned_compiled_method == NULL || cm == NULL, "should reset to NULL before writing a new value");
2083     _scanned_compiled_method = cm;
2084   }
2085 
2086   // Hide sweeper thread from external view.
2087   bool is_hidden_from_external_view() const { return true; }
2088 
2089   bool is_Code_cache_sweeper_thread() const { return true; }
2090 
2091   // Prevent GC from unloading _scanned_compiled_method
2092   void oops_do(OopClosure* f, CodeBlobClosure* cf);
2093   void nmethods_do(CodeBlobClosure* cf);
2094 };
2095 
2096 // A thread used for Compilation.
2097 class CompilerThread : public JavaThread {
2098   friend class VMStructs;
2099  private:
2100   CompilerCounters* _counters;
2101 
2102   ciEnv*                _env;
2103   CompileLog*           _log;
2104   CompileTask* volatile _task;  // print_threads_compiling can read this concurrently.
2105   CompileQueue*         _queue;
2106   BufferBlob*           _buffer_blob;
2107 
2108   AbstractCompiler*     _compiler;
2109   TimeStamp             _idle_time;
2110 
2111  public:
2112 
2113   static CompilerThread* current();
2114 
2115   CompilerThread(CompileQueue* queue, CompilerCounters* counters);
2116   ~CompilerThread();
2117 
2118   bool is_Compiler_thread() const                { return true; }
2119 
2120   virtual bool can_call_java() const;
2121 
2122   // Hide native compiler threads from external view.
2123   bool is_hidden_from_external_view() const      { return !can_call_java(); }
2124 
2125   void set_compiler(AbstractCompiler* c)         { _compiler = c; }
2126   AbstractCompiler* compiler() const             { return _compiler; }
2127 
2128   CompileQueue* queue()        const             { return _queue; }
2129   CompilerCounters* counters() const             { return _counters; }
2130 
2131   // Get/set the thread's compilation environment.
2132   ciEnv*        env()                            { return _env; }
2133   void          set_env(ciEnv* env)              { _env = env; }
2134 
2135   BufferBlob*   get_buffer_blob() const          { return _buffer_blob; }
2136   void          set_buffer_blob(BufferBlob* b)   { _buffer_blob = b; }
2137 
2138   // Get/set the thread's logging information
2139   CompileLog*   log()                            { return _log; }
2140   void          init_log(CompileLog* log) {
2141     // Set once, for good.
2142     assert(_log == NULL, "set only once");
2143     _log = log;
2144   }
2145 
2146   void start_idle_timer()                        { _idle_time.update(); }
2147   jlong idle_time_millis() {
2148     return TimeHelper::counter_to_millis(_idle_time.ticks_since_update());
2149   }
2150 
2151 #ifndef PRODUCT
2152  private:
2153   IdealGraphPrinter *_ideal_graph_printer;
2154  public:
2155   IdealGraphPrinter *ideal_graph_printer()           { return _ideal_graph_printer; }
2156   void set_ideal_graph_printer(IdealGraphPrinter *n) { _ideal_graph_printer = n; }
2157 #endif
2158 
2159   // Get/set the thread's current task
2160   CompileTask* task()                      { return _task; }
2161   void         set_task(CompileTask* task) { _task = task; }
2162 };
2163 
2164 inline CompilerThread* CompilerThread::current() {
2165   return JavaThread::current()->as_CompilerThread();
2166 }
2167 
2168 // The active thread queue. It also keeps track of the current used
2169 // thread priorities.
2170 class Threads: AllStatic {
2171   friend class VMStructs;
2172  private:
2173   static int         _number_of_threads;
2174   static int         _number_of_non_daemon_threads;
2175   static int         _return_code;
2176   static uintx       _thread_claim_token;
2177 #ifdef ASSERT
2178   static bool        _vm_complete;
2179 #endif
2180 
2181   static void initialize_java_lang_classes(JavaThread* main_thread, TRAPS);
2182   static void initialize_jsr292_core_classes(TRAPS);
2183 
2184  public:
2185   // Thread management
2186   // force_daemon is a concession to JNI, where we may need to add a
2187   // thread to the thread list before allocating its thread object
2188   static void add(JavaThread* p, bool force_daemon = false);
2189   static void remove(JavaThread* p, bool is_daemon);
2190   static void non_java_threads_do(ThreadClosure* tc);
2191   static void java_threads_do(ThreadClosure* tc);
2192   static void java_threads_and_vm_thread_do(ThreadClosure* tc);
2193   static void threads_do(ThreadClosure* tc);
2194   static void possibly_parallel_threads_do(bool is_par, ThreadClosure* tc);
2195 
2196   // Initializes the vm and creates the vm thread
2197   static jint create_vm(JavaVMInitArgs* args, bool* canTryAgain);
2198   static void convert_vm_init_libraries_to_agents();
2199   static void create_vm_init_libraries();
2200   static void create_vm_init_agents();
2201   static void shutdown_vm_agents();
2202   static bool destroy_vm();
2203   // Supported VM versions via JNI
2204   // Includes JNI_VERSION_1_1
2205   static jboolean is_supported_jni_version_including_1_1(jint version);
2206   // Does not include JNI_VERSION_1_1
2207   static jboolean is_supported_jni_version(jint version);
2208 
2209   // The "thread claim token" provides a way for threads to be claimed
2210   // by parallel worker tasks.
2211   //
2212   // Each thread contains a "token" field. A task will claim the
2213   // thread only if its token is different from the global token,
2214   // which is updated by calling change_thread_claim_token().  When
2215   // a thread is claimed, it's token is set to the global token value
2216   // so other threads in the same iteration pass won't claim it.
2217   //
2218   // For this to work change_thread_claim_token() needs to be called
2219   // exactly once in sequential code before starting parallel tasks
2220   // that should claim threads.
2221   //
2222   // New threads get their token set to 0 and change_thread_claim_token()
2223   // never sets the global token to 0.
2224   static uintx thread_claim_token() { return _thread_claim_token; }
2225   static void change_thread_claim_token();
2226   static void assert_all_threads_claimed() NOT_DEBUG_RETURN;
2227 
2228   // Apply "f->do_oop" to all root oops in all threads.
2229   // This version may only be called by sequential code.
2230   static void oops_do(OopClosure* f, CodeBlobClosure* cf);
2231   // This version may be called by sequential or parallel code.
2232   static void possibly_parallel_oops_do(bool is_par, OopClosure* f, CodeBlobClosure* cf);
2233 
2234   // Sweeper
2235   static void nmethods_do(CodeBlobClosure* cf);
2236 
2237   // RedefineClasses support
2238   static void metadata_do(MetadataClosure* f);
2239   static void metadata_handles_do(void f(Metadata*));
2240 
2241 #ifdef ASSERT
2242   static bool is_vm_complete() { return _vm_complete; }
2243 #endif // ASSERT
2244 
2245   // Verification
2246   static void verify();
2247   static void print_on(outputStream* st, bool print_stacks, bool internal_format, bool print_concurrent_locks, bool print_extended_info);
2248   static void print(bool print_stacks, bool internal_format) {
2249     // this function is only used by debug.cpp
2250     print_on(tty, print_stacks, internal_format, false /* no concurrent lock printed */, false /* simple format */);
2251   }
2252   static void print_on_error(outputStream* st, Thread* current, char* buf, int buflen);
2253   static void print_on_error(Thread* this_thread, outputStream* st, Thread* current, char* buf,
2254                              int buflen, bool* found_current);
2255   static void print_threads_compiling(outputStream* st, char* buf, int buflen, bool short_form = false);
2256 
2257   // Get Java threads that are waiting to enter a monitor.
2258   static GrowableArray<JavaThread*>* get_pending_threads(ThreadsList * t_list,
2259                                                          int count, address monitor);
2260 
2261   // Get owning Java thread from the monitor's owner field.
2262   static JavaThread *owning_thread_from_monitor_owner(ThreadsList * t_list,
2263                                                       address owner);
2264 
2265   // Number of threads on the active threads list
2266   static int number_of_threads()                 { return _number_of_threads; }
2267   // Number of non-daemon threads on the active threads list
2268   static int number_of_non_daemon_threads()      { return _number_of_non_daemon_threads; }
2269 
2270   // Deoptimizes all frames tied to marked nmethods
2271   static void deoptimized_wrt_marked_nmethods();
2272 
2273   struct Test;                  // For private gtest access.
2274 };
2275 
2276 
2277 // Thread iterator
2278 class ThreadClosure: public StackObj {
2279  public:
2280   virtual void do_thread(Thread* thread) = 0;
2281 };
2282 
2283 class SignalHandlerMark: public StackObj {
2284  private:
2285   Thread* _thread;
2286  public:
2287   SignalHandlerMark(Thread* t) {
2288     _thread = t;
2289     if (_thread) _thread->enter_signal_handler();
2290   }
2291   ~SignalHandlerMark() {
2292     if (_thread) _thread->leave_signal_handler();
2293     _thread = NULL;
2294   }
2295 };
2296 
2297 
2298 #endif // SHARE_RUNTIME_THREAD_HPP
--- EOF ---