1 /*
   2  * Copyright (c) 1997, 2014, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  *
  23  */
  24 
  25 #ifndef SHARE_VM_RUNTIME_THREAD_HPP
  26 #define SHARE_VM_RUNTIME_THREAD_HPP
  27 
  28 #include "memory/allocation.hpp"
  29 #include "memory/threadLocalAllocBuffer.hpp"
  30 #include "oops/oop.hpp"
  31 #include "prims/jni.h"
  32 #include "prims/jvmtiExport.hpp"
  33 #include "runtime/frame.hpp"
  34 #include "runtime/javaFrameAnchor.hpp"
  35 #include "runtime/jniHandles.hpp"
  36 #include "runtime/mutexLocker.hpp"
  37 #include "runtime/os.hpp"
  38 #include "runtime/osThread.hpp"
  39 #include "runtime/park.hpp"
  40 #include "runtime/safepoint.hpp"
  41 #include "runtime/stubRoutines.hpp"
  42 #include "runtime/threadLocalStorage.hpp"
  43 #include "runtime/unhandledOops.hpp"
  44 #include "utilities/macros.hpp"
  45 
  46 #if INCLUDE_NMT
  47 #include "services/memRecorder.hpp"
  48 #endif // INCLUDE_NMT
  49 
  50 #include "trace/traceBackend.hpp"
  51 #include "trace/traceMacros.hpp"
  52 #include "utilities/exceptions.hpp"
  53 #include "utilities/top.hpp"
  54 #if INCLUDE_ALL_GCS
  55 #include "gc_implementation/g1/dirtyCardQueue.hpp"
  56 #include "gc_implementation/g1/satbQueue.hpp"
  57 #endif // INCLUDE_ALL_GCS
  58 #ifdef ZERO
  59 #ifdef TARGET_ARCH_zero
  60 # include "stack_zero.hpp"
  61 #endif
  62 #endif
  63 
  64 class ThreadSafepointState;
  65 class ThreadProfiler;
  66 
  67 class JvmtiThreadState;
  68 class JvmtiGetLoadedClassesClosure;
  69 class ThreadStatistics;
  70 class ConcurrentLocksDump;
  71 class ParkEvent;
  72 class Parker;
  73 
  74 class ciEnv;
  75 class CompileThread;
  76 class CompileLog;
  77 class CompileTask;
  78 class CompileQueue;
  79 class CompilerCounters;
  80 class vframeArray;
  81 
  82 class DeoptResourceMark;
  83 class jvmtiDeferredLocalVariableSet;
  84 
  85 class GCTaskQueue;
  86 class ThreadClosure;
  87 class IdealGraphPrinter;
  88 
  89 DEBUG_ONLY(class ResourceMark;)
  90 
  91 class WorkerThread;
  92 
  93 // Class hierarchy
  94 // - Thread
  95 //   - NamedThread
  96 //     - VMThread
  97 //     - ConcurrentGCThread
  98 //     - WorkerThread
  99 //       - GangWorker
 100 //       - GCTaskThread
 101 //   - JavaThread
 102 //   - WatcherThread
 103 
 104 class Thread: public ThreadShadow {
 105   friend class VMStructs;
 106  private:
 107   // Exception handling
 108   // (Note: _pending_exception and friends are in ThreadShadow)
 109   //oop       _pending_exception;                // pending exception for current thread
 110   // const char* _exception_file;                   // file information for exception (debugging only)
 111   // int         _exception_line;                   // line information for exception (debugging only)
 112  protected:
 113   // Support for forcing alignment of thread objects for biased locking
 114   void*       _real_malloc_address;
 115  public:
 116   void* operator new(size_t size) throw() { return allocate(size, true); }
 117   void* operator new(size_t size, const std::nothrow_t& nothrow_constant) throw() {
 118     return allocate(size, false); }
 119   void  operator delete(void* p);
 120 
 121  protected:
 122    static void* allocate(size_t size, bool throw_excpt, MEMFLAGS flags = mtThread);
 123  private:
 124 
 125   // ***************************************************************
 126   // Suspend and resume support
 127   // ***************************************************************
 128   //
 129   // VM suspend/resume no longer exists - it was once used for various
 130   // things including safepoints but was deprecated and finally removed
 131   // in Java 7. Because VM suspension was considered "internal" Java-level
 132   // suspension was considered "external", and this legacy naming scheme
 133   // remains.
 134   //
 135   // External suspend/resume requests come from JVM_SuspendThread,
 136   // JVM_ResumeThread, JVMTI SuspendThread, and finally JVMTI
 137   // ResumeThread. External
 138   // suspend requests cause _external_suspend to be set and external
 139   // resume requests cause _external_suspend to be cleared.
 140   // External suspend requests do not nest on top of other external
 141   // suspend requests. The higher level APIs reject suspend requests
 142   // for already suspended threads.
 143   //
 144   // The external_suspend
 145   // flag is checked by has_special_runtime_exit_condition() and java thread
 146   // will self-suspend when handle_special_runtime_exit_condition() is
 147   // called. Most uses of the _thread_blocked state in JavaThreads are
 148   // considered the same as being externally suspended; if the blocking
 149   // condition lifts, the JavaThread will self-suspend. Other places
 150   // where VM checks for external_suspend include:
 151   //   + mutex granting (do not enter monitors when thread is suspended)
 152   //   + state transitions from _thread_in_native
 153   //
 154   // In general, java_suspend() does not wait for an external suspend
 155   // request to complete. When it returns, the only guarantee is that
 156   // the _external_suspend field is true.
 157   //
 158   // wait_for_ext_suspend_completion() is used to wait for an external
 159   // suspend request to complete. External suspend requests are usually
 160   // followed by some other interface call that requires the thread to
 161   // be quiescent, e.g., GetCallTrace(). By moving the "wait time" into
 162   // the interface that requires quiescence, we give the JavaThread a
 163   // chance to self-suspend before we need it to be quiescent. This
 164   // improves overall suspend/query performance.
 165   //
 166   // _suspend_flags controls the behavior of java_ suspend/resume.
 167   // It must be set under the protection of SR_lock. Read from the flag is
 168   // OK without SR_lock as long as the value is only used as a hint.
 169   // (e.g., check _external_suspend first without lock and then recheck
 170   // inside SR_lock and finish the suspension)
 171   //
 172   // _suspend_flags is also overloaded for other "special conditions" so
 173   // that a single check indicates whether any special action is needed
 174   // eg. for async exceptions.
 175   // -------------------------------------------------------------------
 176   // Notes:
 177   // 1. The suspend/resume logic no longer uses ThreadState in OSThread
 178   // but we still update its value to keep other part of the system (mainly
 179   // JVMTI) happy. ThreadState is legacy code (see notes in
 180   // osThread.hpp).
 181   //
 182   // 2. It would be more natural if set_external_suspend() is private and
 183   // part of java_suspend(), but that probably would affect the suspend/query
 184   // performance. Need more investigation on this.
 185   //
 186 
 187   // suspend/resume lock: used for self-suspend
 188   Monitor* _SR_lock;
 189 
 190  protected:
 191   enum SuspendFlags {
 192     // NOTE: avoid using the sign-bit as cc generates different test code
 193     //       when the sign-bit is used, and sometimes incorrectly - see CR 6398077
 194 
 195     _external_suspend       = 0x20000000U, // thread is asked to self suspend
 196     _ext_suspended          = 0x40000000U, // thread has self-suspended
 197     _deopt_suspend          = 0x10000000U, // thread needs to self suspend for deopt
 198 
 199     _has_async_exception    = 0x00000001U, // there is a pending async exception
 200     _critical_native_unlock = 0x00000002U  // Must call back to unlock JNI critical lock
 201   };
 202 
 203   // various suspension related flags - atomically updated
 204   // overloaded for async exception checking in check_special_condition_for_native_trans.
 205   volatile uint32_t _suspend_flags;
 206 
 207  private:
 208   int _num_nested_signal;
 209 
 210  public:
 211   void enter_signal_handler() { _num_nested_signal++; }
 212   void leave_signal_handler() { _num_nested_signal--; }
 213   bool is_inside_signal_handler() const { return _num_nested_signal > 0; }
 214 
 215  private:
 216   // Debug tracing
 217   static void trace(const char* msg, const Thread* const thread) PRODUCT_RETURN;
 218 
 219   // Active_handles points to a block of handles
 220   JNIHandleBlock* _active_handles;
 221 
 222   // One-element thread local free list
 223   JNIHandleBlock* _free_handle_block;
 224 
 225   // Point to the last handle mark
 226   HandleMark* _last_handle_mark;
 227 
 228   // The parity of the last strong_roots iteration in which this thread was
 229   // claimed as a task.
 230   jint _oops_do_parity;
 231 
 232   public:
 233    void set_last_handle_mark(HandleMark* mark)   { _last_handle_mark = mark; }
 234    HandleMark* last_handle_mark() const          { return _last_handle_mark; }
 235   private:
 236 
 237   // debug support for checking if code does allow safepoints or not
 238   // GC points in the VM can happen because of allocation, invoking a VM operation, or blocking on
 239   // mutex, or blocking on an object synchronizer (Java locking).
 240   // If !allow_safepoint(), then an assertion failure will happen in any of the above cases
 241   // If !allow_allocation(), then an assertion failure will happen during allocation
 242   // (Hence, !allow_safepoint() => !allow_allocation()).
 243   //
 244   // The two classes No_Safepoint_Verifier and No_Allocation_Verifier are used to set these counters.
 245   //
 246   NOT_PRODUCT(int _allow_safepoint_count;)      // If 0, thread allow a safepoint to happen
 247   debug_only(int _allow_allocation_count;)     // If 0, the thread is allowed to allocate oops.
 248 
 249   // Used by SkipGCALot class.
 250   NOT_PRODUCT(bool _skip_gcalot;)               // Should we elide gc-a-lot?
 251 
 252   friend class No_Alloc_Verifier;
 253   friend class No_Safepoint_Verifier;
 254   friend class Pause_No_Safepoint_Verifier;
 255   friend class ThreadLocalStorage;
 256   friend class GC_locker;
 257 
 258   ThreadLocalAllocBuffer _tlab;                 // Thread-local eden
 259   jlong _allocated_bytes;                       // Cumulative number of bytes allocated on
 260                                                 // the Java heap
 261 
 262   TRACE_DATA _trace_data;                       // Thread-local data for tracing
 263 
 264   int   _vm_operation_started_count;            // VM_Operation support
 265   int   _vm_operation_completed_count;          // VM_Operation support
 266 
 267   ObjectMonitor* _current_pending_monitor;      // ObjectMonitor this thread
 268                                                 // is waiting to lock
 269   bool _current_pending_monitor_is_from_java;   // locking is from Java code
 270 
 271   // ObjectMonitor on which this thread called Object.wait()
 272   ObjectMonitor* _current_waiting_monitor;
 273 
 274   // Private thread-local objectmonitor list - a simple cache organized as a SLL.
 275  public:
 276   ObjectMonitor* omFreeList;
 277   int omFreeCount;                              // length of omFreeList
 278   int omFreeProvision;                          // reload chunk size
 279   ObjectMonitor* omInUseList;                   // SLL to track monitors in circulation
 280   int omInUseCount;                             // length of omInUseList
 281 
 282 #ifdef ASSERT
 283  private:
 284   bool _visited_for_critical_count;
 285 
 286  public:
 287   void set_visited_for_critical_count(bool z) { _visited_for_critical_count = z; }
 288   bool was_visited_for_critical_count() const   { return _visited_for_critical_count; }
 289 #endif
 290 
 291  public:
 292   enum {
 293     is_definitely_current_thread = true
 294   };
 295 
 296   // Constructor
 297   Thread();
 298   virtual ~Thread();
 299 
 300   // initializtion
 301   void initialize_thread_local_storage();
 302 
 303   // thread entry point
 304   virtual void run();
 305 
 306   // Testers
 307   virtual bool is_VM_thread()       const            { return false; }
 308   virtual bool is_Java_thread()     const            { return false; }
 309   virtual bool is_Compiler_thread() const            { return false; }
 310   virtual bool is_hidden_from_external_view() const  { return false; }
 311   virtual bool is_jvmti_agent_thread() const         { return false; }
 312   // True iff the thread can perform GC operations at a safepoint.
 313   // Generally will be true only of VM thread and parallel GC WorkGang
 314   // threads.
 315   virtual bool is_GC_task_thread() const             { return false; }
 316   virtual bool is_Watcher_thread() const             { return false; }
 317   virtual bool is_ConcurrentGC_thread() const        { return false; }
 318   virtual bool is_Named_thread() const               { return false; }
 319   virtual bool is_Worker_thread() const              { return false; }
 320 
 321   // Casts
 322   virtual WorkerThread* as_Worker_thread() const     { return NULL; }
 323 
 324   virtual char* name() const { return (char*)"Unknown thread"; }
 325 
 326   // Returns the current thread
 327   static inline Thread* current();
 328 
 329   // Common thread operations
 330   static void set_priority(Thread* thread, ThreadPriority priority);
 331   static ThreadPriority get_priority(const Thread* const thread);
 332   static void start(Thread* thread);
 333   static void interrupt(Thread* thr);
 334   static bool is_interrupted(Thread* thr, bool clear_interrupted);
 335 
 336   void set_native_thread_name(const char *name) {
 337     assert(Thread::current() == this, "set_native_thread_name can only be called on the current thread");
 338     os::set_native_thread_name(name);
 339   }
 340 
 341   ObjectMonitor** omInUseList_addr()             { return (ObjectMonitor **)&omInUseList; }
 342   Monitor* SR_lock() const                       { return _SR_lock; }
 343 
 344   bool has_async_exception() const { return (_suspend_flags & _has_async_exception) != 0; }
 345 
 346   inline void set_suspend_flag(SuspendFlags f);
 347   inline void clear_suspend_flag(SuspendFlags f);
 348 
 349   inline void set_has_async_exception();
 350   inline void clear_has_async_exception();
 351 
 352   bool do_critical_native_unlock() const { return (_suspend_flags & _critical_native_unlock) != 0; }
 353 
 354   inline void set_critical_native_unlock();
 355   inline void clear_critical_native_unlock();
 356 
 357   // Support for Unhandled Oop detection
 358 #ifdef CHECK_UNHANDLED_OOPS
 359  private:
 360   UnhandledOops* _unhandled_oops;
 361  public:
 362   UnhandledOops* unhandled_oops() { return _unhandled_oops; }
 363   // Mark oop safe for gc.  It may be stack allocated but won't move.
 364   void allow_unhandled_oop(oop *op) {
 365     if (CheckUnhandledOops) unhandled_oops()->allow_unhandled_oop(op);
 366   }
 367   // Clear oops at safepoint so crashes point to unhandled oop violator
 368   void clear_unhandled_oops() {
 369     if (CheckUnhandledOops) unhandled_oops()->clear_unhandled_oops();
 370   }
 371 #endif // CHECK_UNHANDLED_OOPS
 372 
 373 #ifndef PRODUCT
 374   bool skip_gcalot()           { return _skip_gcalot; }
 375   void set_skip_gcalot(bool v) { _skip_gcalot = v;    }
 376 #endif
 377 
 378  public:
 379   // Installs a pending exception to be inserted later
 380   static void send_async_exception(oop thread_oop, oop java_throwable);
 381 
 382   // Resource area
 383   ResourceArea* resource_area() const            { return _resource_area; }
 384   void set_resource_area(ResourceArea* area)     { _resource_area = area; }
 385 
 386   OSThread* osthread() const                     { return _osthread;   }
 387   void set_osthread(OSThread* thread)            { _osthread = thread; }
 388 
 389   // JNI handle support
 390   JNIHandleBlock* active_handles() const         { return _active_handles; }
 391   void set_active_handles(JNIHandleBlock* block) { _active_handles = block; }
 392   JNIHandleBlock* free_handle_block() const      { return _free_handle_block; }
 393   void set_free_handle_block(JNIHandleBlock* block) { _free_handle_block = block; }
 394 
 395   // Internal handle support
 396   HandleArea* handle_area() const                { return _handle_area; }
 397   void set_handle_area(HandleArea* area)         { _handle_area = area; }
 398 
 399   GrowableArray<Metadata*>* metadata_handles() const          { return _metadata_handles; }
 400   void set_metadata_handles(GrowableArray<Metadata*>* handles){ _metadata_handles = handles; }
 401 
 402   // Thread-Local Allocation Buffer (TLAB) support
 403   ThreadLocalAllocBuffer& tlab()                 { return _tlab; }
 404   void initialize_tlab() {
 405     if (UseTLAB) {
 406       tlab().initialize();
 407     }
 408   }
 409 
 410   jlong allocated_bytes()               { return _allocated_bytes; }
 411   void set_allocated_bytes(jlong value) { _allocated_bytes = value; }
 412   void incr_allocated_bytes(jlong size) { _allocated_bytes += size; }
 413   inline jlong cooked_allocated_bytes();
 414 
 415   TRACE_DATA* trace_data()              { return &_trace_data; }
 416 
 417   // VM operation support
 418   int vm_operation_ticket()                      { return ++_vm_operation_started_count; }
 419   int vm_operation_completed_count()             { return _vm_operation_completed_count; }
 420   void increment_vm_operation_completed_count()  { _vm_operation_completed_count++; }
 421 
 422   // For tracking the heavyweight monitor the thread is pending on.
 423   ObjectMonitor* current_pending_monitor() {
 424     return _current_pending_monitor;
 425   }
 426   void set_current_pending_monitor(ObjectMonitor* monitor) {
 427     _current_pending_monitor = monitor;
 428   }
 429   void set_current_pending_monitor_is_from_java(bool from_java) {
 430     _current_pending_monitor_is_from_java = from_java;
 431   }
 432   bool current_pending_monitor_is_from_java() {
 433     return _current_pending_monitor_is_from_java;
 434   }
 435 
 436   // For tracking the ObjectMonitor on which this thread called Object.wait()
 437   ObjectMonitor* current_waiting_monitor() {
 438     return _current_waiting_monitor;
 439   }
 440   void set_current_waiting_monitor(ObjectMonitor* monitor) {
 441     _current_waiting_monitor = monitor;
 442   }
 443 
 444   // GC support
 445   // Apply "f->do_oop" to all root oops in "this".
 446   // Apply "cld_f->do_cld" to CLDs that are otherwise not kept alive.
 447   //   Used by JavaThread::oops_do.
 448   // Apply "cf->do_code_blob" (if !NULL) to all code blobs active in frames
 449   virtual void oops_do(OopClosure* f, CLDClosure* cld_f, CodeBlobClosure* cf);
 450 
 451   // Handles the parallel case for the method below.
 452 private:
 453   bool claim_oops_do_par_case(int collection_parity);
 454 public:
 455   // Requires that "collection_parity" is that of the current roots
 456   // iteration.  If "is_par" is false, sets the parity of "this" to
 457   // "collection_parity", and returns "true".  If "is_par" is true,
 458   // uses an atomic instruction to set the current threads parity to
 459   // "collection_parity", if it is not already.  Returns "true" iff the
 460   // calling thread does the update, this indicates that the calling thread
 461   // has claimed the thread's stack as a root groop in the current
 462   // collection.
 463   bool claim_oops_do(bool is_par, int collection_parity) {
 464     if (!is_par) {
 465       _oops_do_parity = collection_parity;
 466       return true;
 467     } else {
 468       return claim_oops_do_par_case(collection_parity);
 469     }
 470   }
 471 
 472   // Sweeper support
 473   void nmethods_do(CodeBlobClosure* cf);
 474 
 475   // jvmtiRedefineClasses support
 476   void metadata_do(void f(Metadata*));
 477 
 478   // Used by fast lock support
 479   virtual bool is_lock_owned(address adr) const;
 480 
 481   // Check if address is in the stack of the thread (not just for locks).
 482   // Warning: the method can only be used on the running thread
 483   bool is_in_stack(address adr) const;
 484   // Check if address is in the usable part of the stack (excludes protected
 485   // guard pages)
 486   bool is_in_usable_stack(address adr) const;
 487 
 488   // Sets this thread as starting thread. Returns failure if thread
 489   // creation fails due to lack of memory, too many threads etc.
 490   bool set_as_starting_thread();
 491 
 492  protected:
 493   // OS data associated with the thread
 494   OSThread* _osthread;  // Platform-specific thread information
 495 
 496   // Thread local resource area for temporary allocation within the VM
 497   ResourceArea* _resource_area;
 498 
 499   DEBUG_ONLY(ResourceMark* _current_resource_mark;)
 500 
 501   // Thread local handle area for allocation of handles within the VM
 502   HandleArea* _handle_area;
 503   GrowableArray<Metadata*>* _metadata_handles;
 504 
 505   // Support for stack overflow handling, get_thread, etc.
 506   address          _stack_base;
 507   size_t           _stack_size;
 508   uintptr_t        _self_raw_id;      // used by get_thread (mutable)
 509   int              _lgrp_id;
 510 
 511  public:
 512   // Stack overflow support
 513   address stack_base() const           { assert(_stack_base != NULL,"Sanity check"); return _stack_base; }
 514 
 515   void    set_stack_base(address base) { _stack_base = base; }
 516   size_t  stack_size() const           { return _stack_size; }
 517   void    set_stack_size(size_t size)  { _stack_size = size; }
 518   void    record_stack_base_and_size();
 519 
 520   bool    on_local_stack(address adr) const {
 521     /* QQQ this has knowledge of direction, ought to be a stack method */
 522     return (_stack_base >= adr && adr >= (_stack_base - _stack_size));
 523   }
 524 
 525   uintptr_t self_raw_id()                    { return _self_raw_id; }
 526   void      set_self_raw_id(uintptr_t value) { _self_raw_id = value; }
 527 
 528   int     lgrp_id() const        { return _lgrp_id; }
 529   void    set_lgrp_id(int value) { _lgrp_id = value; }
 530 
 531   // Printing
 532   virtual void print_on(outputStream* st) const;
 533   void print() const { print_on(tty); }
 534   virtual void print_on_error(outputStream* st, char* buf, int buflen) const;
 535 
 536   // Debug-only code
 537 #ifdef ASSERT
 538  private:
 539   // Deadlock detection support for Mutex locks. List of locks own by thread.
 540   Monitor* _owned_locks;
 541   // Mutex::set_owner_implementation is the only place where _owned_locks is modified,
 542   // thus the friendship
 543   friend class Mutex;
 544   friend class Monitor;
 545 
 546  public:
 547   void print_owned_locks_on(outputStream* st) const;
 548   void print_owned_locks() const                 { print_owned_locks_on(tty);    }
 549   Monitor* owned_locks() const                   { return _owned_locks;          }
 550   bool owns_locks() const                        { return owned_locks() != NULL; }
 551   bool owns_locks_but_compiled_lock() const;
 552 
 553   // Deadlock detection
 554   bool allow_allocation()                        { return _allow_allocation_count == 0; }
 555   ResourceMark* current_resource_mark()          { return _current_resource_mark; }
 556   void set_current_resource_mark(ResourceMark* rm) { _current_resource_mark = rm; }
 557 #endif
 558 
 559   void check_for_valid_safepoint_state(bool potential_vm_operation) PRODUCT_RETURN;
 560 
 561  private:
 562   volatile int _jvmti_env_iteration_count;
 563 
 564  public:
 565   void entering_jvmti_env_iteration()            { ++_jvmti_env_iteration_count; }
 566   void leaving_jvmti_env_iteration()             { --_jvmti_env_iteration_count; }
 567   bool is_inside_jvmti_env_iteration()           { return _jvmti_env_iteration_count > 0; }
 568 
 569   // Code generation
 570   static ByteSize exception_file_offset()        { return byte_offset_of(Thread, _exception_file); }
 571   static ByteSize exception_line_offset()        { return byte_offset_of(Thread, _exception_line); }
 572   static ByteSize active_handles_offset()        { return byte_offset_of(Thread, _active_handles); }
 573 
 574   static ByteSize stack_base_offset()            { return byte_offset_of(Thread, _stack_base); }
 575   static ByteSize stack_size_offset()            { return byte_offset_of(Thread, _stack_size); }
 576 
 577 #define TLAB_FIELD_OFFSET(name) \
 578   static ByteSize tlab_##name##_offset()         { return byte_offset_of(Thread, _tlab) + ThreadLocalAllocBuffer::name##_offset(); }
 579 
 580   TLAB_FIELD_OFFSET(start)
 581   TLAB_FIELD_OFFSET(end)
 582   TLAB_FIELD_OFFSET(top)
 583   TLAB_FIELD_OFFSET(pf_top)
 584   TLAB_FIELD_OFFSET(size)                   // desired_size
 585   TLAB_FIELD_OFFSET(refill_waste_limit)
 586   TLAB_FIELD_OFFSET(number_of_refills)
 587   TLAB_FIELD_OFFSET(fast_refill_waste)
 588   TLAB_FIELD_OFFSET(slow_allocations)
 589 
 590 #undef TLAB_FIELD_OFFSET
 591 
 592   static ByteSize allocated_bytes_offset()       { return byte_offset_of(Thread, _allocated_bytes); }
 593 
 594  public:
 595   volatile intptr_t _Stalled;
 596   volatile int _TypeTag;
 597   ParkEvent * _ParkEvent;                     // for synchronized()
 598   ParkEvent * _SleepEvent;                    // for Thread.sleep
 599   ParkEvent * _MutexEvent;                    // for native internal Mutex/Monitor
 600   ParkEvent * _MuxEvent;                      // for low-level muxAcquire-muxRelease
 601   int NativeSyncRecursion;                    // diagnostic
 602 
 603   volatile int _OnTrap;                       // Resume-at IP delta
 604   jint _hashStateW;                           // Marsaglia Shift-XOR thread-local RNG
 605   jint _hashStateX;                           // thread-specific hashCode generator state
 606   jint _hashStateY;
 607   jint _hashStateZ;
 608   void * _schedctl;
 609 
 610 
 611   volatile jint rng[4];                      // RNG for spin loop
 612 
 613   // Low-level leaf-lock primitives used to implement synchronization
 614   // and native monitor-mutex infrastructure.
 615   // Not for general synchronization use.
 616   static void SpinAcquire(volatile int * Lock, const char * Name);
 617   static void SpinRelease(volatile int * Lock);
 618   static void muxAcquire(volatile intptr_t * Lock, const char * Name);
 619   static void muxAcquireW(volatile intptr_t * Lock, ParkEvent * ev);
 620   static void muxRelease(volatile intptr_t * Lock);
 621 };
 622 
 623 // Inline implementation of Thread::current()
 624 // Thread::current is "hot" it's called > 128K times in the 1st 500 msecs of
 625 // startup.
 626 // ThreadLocalStorage::thread is warm -- it's called > 16K times in the same
 627 // period.   This is inlined in thread_<os_family>.inline.hpp.
 628 
 629 inline Thread* Thread::current() {
 630 #ifdef ASSERT
 631 // This function is very high traffic. Define PARANOID to enable expensive
 632 // asserts.
 633 #ifdef PARANOID
 634   // Signal handler should call ThreadLocalStorage::get_thread_slow()
 635   Thread* t = ThreadLocalStorage::get_thread_slow();
 636   assert(t != NULL && !t->is_inside_signal_handler(),
 637          "Don't use Thread::current() inside signal handler");
 638 #endif
 639 #endif
 640   Thread* thread = ThreadLocalStorage::thread();
 641   assert(thread != NULL, "just checking");
 642   return thread;
 643 }
 644 
 645 // Name support for threads.  non-JavaThread subclasses with multiple
 646 // uniquely named instances should derive from this.
 647 class NamedThread: public Thread {
 648   friend class VMStructs;
 649   enum {
 650     max_name_len = 64
 651   };
 652  private:
 653   char* _name;
 654   // log JavaThread being processed by oops_do
 655   JavaThread* _processed_thread;
 656 
 657  public:
 658   NamedThread();
 659   ~NamedThread();
 660   // May only be called once per thread.
 661   void set_name(const char* format, ...)  ATTRIBUTE_PRINTF(2, 3);
 662   virtual bool is_Named_thread() const { return true; }
 663   virtual char* name() const { return _name == NULL ? (char*)"Unknown Thread" : _name; }
 664   JavaThread *processed_thread() { return _processed_thread; }
 665   void set_processed_thread(JavaThread *thread) { _processed_thread = thread; }
 666   virtual void print_on(outputStream* st) const;
 667 };
 668 
 669 // Worker threads are named and have an id of an assigned work.
 670 class WorkerThread: public NamedThread {
 671 private:
 672   uint _id;
 673 public:
 674   WorkerThread() : _id(0)               { }
 675   virtual bool is_Worker_thread() const { return true; }
 676 
 677   virtual WorkerThread* as_Worker_thread() const {
 678     assert(is_Worker_thread(), "Dubious cast to WorkerThread*?");
 679     return (WorkerThread*) this;
 680   }
 681 
 682   void set_id(uint work_id)             { _id = work_id; }
 683   uint id() const                       { return _id; }
 684 };
 685 
 686 // A single WatcherThread is used for simulating timer interrupts.
 687 class WatcherThread: public Thread {
 688   friend class VMStructs;
 689  public:
 690   virtual void run();
 691 
 692  private:
 693   static WatcherThread* _watcher_thread;
 694 
 695   static bool _startable;
 696   volatile static bool _should_terminate; // updated without holding lock
 697 
 698   os::WatcherThreadCrashProtection* _crash_protection;
 699  public:
 700   enum SomeConstants {
 701     delay_interval = 10                          // interrupt delay in milliseconds
 702   };
 703 
 704   // Constructor
 705   WatcherThread();
 706 
 707   // Tester
 708   bool is_Watcher_thread() const                 { return true; }
 709 
 710   // Printing
 711   char* name() const { return (char*)"VM Periodic Task Thread"; }
 712   void print_on(outputStream* st) const;
 713   void unpark();
 714 
 715   // Returns the single instance of WatcherThread
 716   static WatcherThread* watcher_thread()         { return _watcher_thread; }
 717 
 718   // Create and start the single instance of WatcherThread, or stop it on shutdown
 719   static void start();
 720   static void stop();
 721   // Only allow start once the VM is sufficiently initialized
 722   // Otherwise the first task to enroll will trigger the start
 723   static void make_startable();
 724 
 725   void set_crash_protection(os::WatcherThreadCrashProtection* crash_protection) {
 726     assert(Thread::current()->is_Watcher_thread(), "Can only be set by WatcherThread");
 727     _crash_protection = crash_protection;
 728   }
 729 
 730   bool has_crash_protection() const { return _crash_protection != NULL; }
 731   os::WatcherThreadCrashProtection* crash_protection() const { return _crash_protection; }
 732 
 733  private:
 734   int sleep() const;
 735 };
 736 
 737 
 738 class CompilerThread;
 739 
 740 typedef void (*ThreadFunction)(JavaThread*, TRAPS);
 741 
 742 class JavaThread: public Thread {
 743   friend class VMStructs;
 744  private:
 745   JavaThread*    _next;                          // The next thread in the Threads list
 746   oop            _threadObj;                     // The Java level thread object
 747 
 748 #ifdef ASSERT
 749  private:
 750   int _java_call_counter;
 751 
 752  public:
 753   int  java_call_counter()                       { return _java_call_counter; }
 754   void inc_java_call_counter()                   { _java_call_counter++; }
 755   void dec_java_call_counter() {
 756     assert(_java_call_counter > 0, "Invalid nesting of JavaCallWrapper");
 757     _java_call_counter--;
 758   }
 759  private:  // restore original namespace restriction
 760 #endif  // ifdef ASSERT
 761 
 762 #ifndef PRODUCT
 763  public:
 764   enum {
 765     jump_ring_buffer_size = 16
 766   };
 767  private:  // restore original namespace restriction
 768 #endif
 769 
 770   JavaFrameAnchor _anchor;                       // Encapsulation of current java frame and it state
 771 
 772   ThreadFunction _entry_point;
 773 
 774   JNIEnv        _jni_environment;
 775 
 776   // Deopt support
 777   DeoptResourceMark*  _deopt_mark;               // Holds special ResourceMark for deoptimization
 778 
 779   intptr_t*      _must_deopt_id;                 // id of frame that needs to be deopted once we
 780                                                  // transition out of native
 781   nmethod*       _deopt_nmethod;                 // nmethod that is currently being deoptimized
 782   vframeArray*  _vframe_array_head;              // Holds the heap of the active vframeArrays
 783   vframeArray*  _vframe_array_last;              // Holds last vFrameArray we popped
 784   // Because deoptimization is lazy we must save jvmti requests to set locals
 785   // in compiled frames until we deoptimize and we have an interpreter frame.
 786   // This holds the pointer to array (yeah like there might be more than one) of
 787   // description of compiled vframes that have locals that need to be updated.
 788   GrowableArray<jvmtiDeferredLocalVariableSet*>* _deferred_locals_updates;
 789 
 790   // Handshake value for fixing 6243940. We need a place for the i2c
 791   // adapter to store the callee Method*. This value is NEVER live
 792   // across a gc point so it does NOT have to be gc'd
 793   // The handshake is open ended since we can't be certain that it will
 794   // be NULLed. This is because we rarely ever see the race and end up
 795   // in handle_wrong_method which is the backend of the handshake. See
 796   // code in i2c adapters and handle_wrong_method.
 797 
 798   Method*       _callee_target;
 799 
 800   // Used to pass back results to the interpreter or generated code running Java code.
 801   oop           _vm_result;    // oop result is GC-preserved
 802   Metadata*     _vm_result_2;  // non-oop result
 803 
 804   // See ReduceInitialCardMarks: this holds the precise space interval of
 805   // the most recent slow path allocation for which compiled code has
 806   // elided card-marks for performance along the fast-path.
 807   MemRegion     _deferred_card_mark;
 808 
 809   MonitorChunk* _monitor_chunks;                 // Contains the off stack monitors
 810                                                  // allocated during deoptimization
 811                                                  // and by JNI_MonitorEnter/Exit
 812 
 813   // Async. requests support
 814   enum AsyncRequests {
 815     _no_async_condition = 0,
 816     _async_exception,
 817     _async_unsafe_access_error
 818   };
 819   AsyncRequests _special_runtime_exit_condition; // Enum indicating pending async. request
 820   oop           _pending_async_exception;
 821 
 822   // Safepoint support
 823  public:                                         // Expose _thread_state for SafeFetchInt()
 824   volatile JavaThreadState _thread_state;
 825  private:
 826   ThreadSafepointState *_safepoint_state;        // Holds information about a thread during a safepoint
 827   address               _saved_exception_pc;     // Saved pc of instruction where last implicit exception happened
 828 
 829   // JavaThread termination support
 830   enum TerminatedTypes {
 831     _not_terminated = 0xDEAD - 2,
 832     _thread_exiting,                             // JavaThread::exit() has been called for this thread
 833     _thread_terminated,                          // JavaThread is removed from thread list
 834     _vm_exited                                   // JavaThread is still executing native code, but VM is terminated
 835                                                  // only VM_Exit can set _vm_exited
 836   };
 837 
 838   // In general a JavaThread's _terminated field transitions as follows:
 839   //
 840   //   _not_terminated => _thread_exiting => _thread_terminated
 841   //
 842   // _vm_exited is a special value to cover the case of a JavaThread
 843   // executing native code after the VM itself is terminated.
 844   volatile TerminatedTypes _terminated;
 845   // suspend/resume support
 846   volatile bool         _suspend_equivalent;     // Suspend equivalent condition
 847   jint                  _in_deopt_handler;       // count of deoptimization
 848                                                  // handlers thread is in
 849   volatile bool         _doing_unsafe_access;    // Thread may fault due to unsafe access
 850   bool                  _do_not_unlock_if_synchronized; // Do not unlock the receiver of a synchronized method (since it was
 851                                                  // never locked) when throwing an exception. Used by interpreter only.
 852 
 853   // JNI attach states:
 854   enum JNIAttachStates {
 855     _not_attaching_via_jni = 1,  // thread is not attaching via JNI
 856     _attaching_via_jni,          // thread is attaching via JNI
 857     _attached_via_jni            // thread has attached via JNI
 858   };
 859 
 860   // A regular JavaThread's _jni_attach_state is _not_attaching_via_jni.
 861   // A native thread that is attaching via JNI starts with a value
 862   // of _attaching_via_jni and transitions to _attached_via_jni.
 863   volatile JNIAttachStates _jni_attach_state;
 864 
 865  public:
 866   // State of the stack guard pages for this thread.
 867   enum StackGuardState {
 868     stack_guard_unused,         // not needed
 869     stack_guard_yellow_disabled,// disabled (temporarily) after stack overflow
 870     stack_guard_enabled         // enabled
 871   };
 872 
 873  private:
 874 
 875   StackGuardState  _stack_guard_state;
 876 
 877   // Precompute the limit of the stack as used in stack overflow checks.
 878   // We load it from here to simplify the stack overflow check in assembly.
 879   address          _stack_overflow_limit;
 880 
 881   // Compiler exception handling (NOTE: The _exception_oop is *NOT* the same as _pending_exception. It is
 882   // used to temp. parsing values into and out of the runtime system during exception handling for compiled
 883   // code)
 884   volatile oop     _exception_oop;               // Exception thrown in compiled code
 885   volatile address _exception_pc;                // PC where exception happened
 886   volatile address _exception_handler_pc;        // PC for handler of exception
 887   volatile int     _is_method_handle_return;     // true (== 1) if the current exception PC is a MethodHandle call site.
 888 
 889   // support for JNI critical regions
 890   jint    _jni_active_critical;                  // count of entries into JNI critical region
 891 
 892   // Checked JNI: function name requires exception check
 893   char* _pending_jni_exception_check_fn;
 894 
 895   // For deadlock detection.
 896   int _depth_first_number;
 897 
 898   // JVMTI PopFrame support
 899   // This is set to popframe_pending to signal that top Java frame should be popped immediately
 900   int _popframe_condition;
 901 
 902 #ifndef PRODUCT
 903   int _jmp_ring_index;
 904   struct {
 905       // We use intptr_t instead of address so debugger doesn't try and display strings
 906       intptr_t _target;
 907       intptr_t _instruction;
 908       const char*  _file;
 909       int _line;
 910   }   _jmp_ring[jump_ring_buffer_size];
 911 #endif /* PRODUCT */
 912 
 913 #if INCLUDE_ALL_GCS
 914   // Support for G1 barriers
 915 
 916   ObjPtrQueue _satb_mark_queue;          // Thread-local log for SATB barrier.
 917   // Set of all such queues.
 918   static SATBMarkQueueSet _satb_mark_queue_set;
 919 
 920   DirtyCardQueue _dirty_card_queue;      // Thread-local log for dirty cards.
 921   // Set of all such queues.
 922   static DirtyCardQueueSet _dirty_card_queue_set;
 923 
 924   void flush_barrier_queues();
 925 #endif // INCLUDE_ALL_GCS
 926 
 927   friend class VMThread;
 928   friend class ThreadWaitTransition;
 929   friend class VM_Exit;
 930 
 931   void initialize();                             // Initialized the instance variables
 932 
 933  public:
 934   // Constructor
 935   JavaThread(bool is_attaching_via_jni = false); // for main thread and JNI attached threads
 936   JavaThread(ThreadFunction entry_point, size_t stack_size = 0);
 937   ~JavaThread();
 938 
 939 #ifdef ASSERT
 940   // verify this JavaThread hasn't be published in the Threads::list yet
 941   void verify_not_published();
 942 #endif
 943 
 944   //JNI functiontable getter/setter for JVMTI jni function table interception API.
 945   void set_jni_functions(struct JNINativeInterface_* functionTable) {
 946     _jni_environment.functions = functionTable;
 947   }
 948   struct JNINativeInterface_* get_jni_functions() {
 949     return (struct JNINativeInterface_ *)_jni_environment.functions;
 950   }
 951 
 952   // This function is called at thread creation to allow
 953   // platform specific thread variables to be initialized.
 954   void cache_global_variables();
 955 
 956   // Executes Shutdown.shutdown()
 957   void invoke_shutdown_hooks();
 958 
 959   // Cleanup on thread exit
 960   enum ExitType {
 961     normal_exit,
 962     jni_detach
 963   };
 964   void exit(bool destroy_vm, ExitType exit_type = normal_exit);
 965 
 966   void cleanup_failed_attach_current_thread();
 967 
 968   // Testers
 969   virtual bool is_Java_thread() const            { return true;  }
 970 
 971   // Thread chain operations
 972   JavaThread* next() const                       { return _next; }
 973   void set_next(JavaThread* p)                   { _next = p; }
 974 
 975   // Thread oop. threadObj() can be NULL for initial JavaThread
 976   // (or for threads attached via JNI)
 977   oop threadObj() const                          { return _threadObj; }
 978   void set_threadObj(oop p)                      { _threadObj = p; }
 979 
 980   ThreadPriority java_priority() const;          // Read from threadObj()
 981 
 982   // Prepare thread and add to priority queue.  If a priority is
 983   // not specified, use the priority of the thread object. Threads_lock
 984   // must be held while this function is called.
 985   void prepare(jobject jni_thread, ThreadPriority prio=NoPriority);
 986 
 987   void set_saved_exception_pc(address pc)        { _saved_exception_pc = pc; }
 988   address saved_exception_pc()                   { return _saved_exception_pc; }
 989 
 990 
 991   ThreadFunction entry_point() const             { return _entry_point; }
 992 
 993   // Allocates a new Java level thread object for this thread. thread_name may be NULL.
 994   void allocate_threadObj(Handle thread_group, char* thread_name, bool daemon, TRAPS);
 995 
 996   // Last frame anchor routines
 997 
 998   JavaFrameAnchor* frame_anchor(void)            { return &_anchor; }
 999 
1000   // last_Java_sp
1001   bool has_last_Java_frame() const               { return _anchor.has_last_Java_frame(); }
1002   intptr_t* last_Java_sp() const                 { return _anchor.last_Java_sp(); }
1003 
1004   // last_Java_pc
1005 
1006   address last_Java_pc(void)                     { return _anchor.last_Java_pc(); }
1007 
1008   // Safepoint support
1009 #ifndef PPC64
1010   JavaThreadState thread_state() const           { return _thread_state; }
1011   void set_thread_state(JavaThreadState s)       { _thread_state = s;    }
1012 #else
1013   // Use membars when accessing volatile _thread_state. See
1014   // Threads::create_vm() for size checks.
1015   inline JavaThreadState thread_state() const;
1016   inline void set_thread_state(JavaThreadState s);
1017 #endif
1018   ThreadSafepointState *safepoint_state() const  { return _safepoint_state; }
1019   void set_safepoint_state(ThreadSafepointState *state) { _safepoint_state = state; }
1020   bool is_at_poll_safepoint()                    { return _safepoint_state->is_at_poll_safepoint(); }
1021 
1022   // thread has called JavaThread::exit() or is terminated
1023   bool is_exiting()                              { return _terminated == _thread_exiting || is_terminated(); }
1024   // thread is terminated (no longer on the threads list); we compare
1025   // against the two non-terminated values so that a freed JavaThread
1026   // will also be considered terminated.
1027   bool is_terminated()                           { return _terminated != _not_terminated && _terminated != _thread_exiting; }
1028   void set_terminated(TerminatedTypes t)         { _terminated = t; }
1029   // special for Threads::remove() which is static:
1030   void set_terminated_value()                    { _terminated = _thread_terminated; }
1031   void block_if_vm_exited();
1032 
1033   bool doing_unsafe_access()                     { return _doing_unsafe_access; }
1034   void set_doing_unsafe_access(bool val)         { _doing_unsafe_access = val; }
1035 
1036   bool do_not_unlock_if_synchronized()             { return _do_not_unlock_if_synchronized; }
1037   void set_do_not_unlock_if_synchronized(bool val) { _do_not_unlock_if_synchronized = val; }
1038 
1039 #if INCLUDE_NMT
1040   // native memory tracking
1041   inline MemRecorder* get_recorder() const          { return (MemRecorder*)_recorder; }
1042   inline void         set_recorder(MemRecorder* rc) { _recorder = rc; }
1043 
1044  private:
1045   // per-thread memory recorder
1046   MemRecorder* volatile _recorder;
1047 #endif // INCLUDE_NMT
1048 
1049   // Suspend/resume support for JavaThread
1050  private:
1051   inline void set_ext_suspended();
1052   inline void clear_ext_suspended();
1053 
1054  public:
1055   void java_suspend();
1056   void java_resume();
1057   int  java_suspend_self();
1058 
1059   void check_and_wait_while_suspended() {
1060     assert(JavaThread::current() == this, "sanity check");
1061 
1062     bool do_self_suspend;
1063     do {
1064       // were we externally suspended while we were waiting?
1065       do_self_suspend = handle_special_suspend_equivalent_condition();
1066       if (do_self_suspend) {
1067         // don't surprise the thread that suspended us by returning
1068         java_suspend_self();
1069         set_suspend_equivalent();
1070       }
1071     } while (do_self_suspend);
1072   }
1073   static void check_safepoint_and_suspend_for_native_trans(JavaThread *thread);
1074   // Check for async exception in addition to safepoint and suspend request.
1075   static void check_special_condition_for_native_trans(JavaThread *thread);
1076 
1077   // Same as check_special_condition_for_native_trans but finishes the
1078   // transition into thread_in_Java mode so that it can potentially
1079   // block.
1080   static void check_special_condition_for_native_trans_and_transition(JavaThread *thread);
1081 
1082   bool is_ext_suspend_completed(bool called_by_wait, int delay, uint32_t *bits);
1083   bool is_ext_suspend_completed_with_lock(uint32_t *bits) {
1084     MutexLockerEx ml(SR_lock(), Mutex::_no_safepoint_check_flag);
1085     // Warning: is_ext_suspend_completed() may temporarily drop the
1086     // SR_lock to allow the thread to reach a stable thread state if
1087     // it is currently in a transient thread state.
1088     return is_ext_suspend_completed(false /*!called_by_wait */,
1089                                     SuspendRetryDelay, bits);
1090   }
1091 
1092   // We cannot allow wait_for_ext_suspend_completion() to run forever or
1093   // we could hang. SuspendRetryCount and SuspendRetryDelay are normally
1094   // passed as the count and delay parameters. Experiments with specific
1095   // calls to wait_for_ext_suspend_completion() can be done by passing
1096   // other values in the code. Experiments with all calls can be done
1097   // via the appropriate -XX options.
1098   bool wait_for_ext_suspend_completion(int count, int delay, uint32_t *bits);
1099 
1100   inline void set_external_suspend();
1101   inline void clear_external_suspend();
1102 
1103   inline void set_deopt_suspend();
1104   inline void clear_deopt_suspend();
1105   bool is_deopt_suspend()         { return (_suspend_flags & _deopt_suspend) != 0; }
1106 
1107   bool is_external_suspend() const {
1108     return (_suspend_flags & _external_suspend) != 0;
1109   }
1110   // Whenever a thread transitions from native to vm/java it must suspend
1111   // if external|deopt suspend is present.
1112   bool is_suspend_after_native() const {
1113     return (_suspend_flags & (_external_suspend | _deopt_suspend) ) != 0;
1114   }
1115 
1116   // external suspend request is completed
1117   bool is_ext_suspended() const {
1118     return (_suspend_flags & _ext_suspended) != 0;
1119   }
1120 
1121   bool is_external_suspend_with_lock() const {
1122     MutexLockerEx ml(SR_lock(), Mutex::_no_safepoint_check_flag);
1123     return is_external_suspend();
1124   }
1125 
1126   // Special method to handle a pending external suspend request
1127   // when a suspend equivalent condition lifts.
1128   bool handle_special_suspend_equivalent_condition() {
1129     assert(is_suspend_equivalent(),
1130       "should only be called in a suspend equivalence condition");
1131     MutexLockerEx ml(SR_lock(), Mutex::_no_safepoint_check_flag);
1132     bool ret = is_external_suspend();
1133     if (!ret) {
1134       // not about to self-suspend so clear suspend equivalence
1135       clear_suspend_equivalent();
1136     }
1137     // implied else:
1138     // We have a pending external suspend request so we leave the
1139     // suspend_equivalent flag set until java_suspend_self() sets
1140     // the ext_suspended flag and clears the suspend_equivalent
1141     // flag. This insures that wait_for_ext_suspend_completion()
1142     // will return consistent values.
1143     return ret;
1144   }
1145 
1146   // utility methods to see if we are doing some kind of suspension
1147   bool is_being_ext_suspended() const            {
1148     MutexLockerEx ml(SR_lock(), Mutex::_no_safepoint_check_flag);
1149     return is_ext_suspended() || is_external_suspend();
1150   }
1151 
1152   bool is_suspend_equivalent() const             { return _suspend_equivalent; }
1153 
1154   void set_suspend_equivalent()                  { _suspend_equivalent = true; };
1155   void clear_suspend_equivalent()                { _suspend_equivalent = false; };
1156 
1157   // Thread.stop support
1158   void send_thread_stop(oop throwable);
1159   AsyncRequests clear_special_runtime_exit_condition() {
1160     AsyncRequests x = _special_runtime_exit_condition;
1161     _special_runtime_exit_condition = _no_async_condition;
1162     return x;
1163   }
1164 
1165   // Are any async conditions present?
1166   bool has_async_condition() { return (_special_runtime_exit_condition != _no_async_condition); }
1167 
1168   void check_and_handle_async_exceptions(bool check_unsafe_error = true);
1169 
1170   // these next two are also used for self-suspension and async exception support
1171   void handle_special_runtime_exit_condition(bool check_asyncs = true);
1172 
1173   // Return true if JavaThread has an asynchronous condition or
1174   // if external suspension is requested.
1175   bool has_special_runtime_exit_condition() {
1176     // We call is_external_suspend() last since external suspend should
1177     // be less common. Because we don't use is_external_suspend_with_lock
1178     // it is possible that we won't see an asynchronous external suspend
1179     // request that has just gotten started, i.e., SR_lock grabbed but
1180     // _external_suspend field change either not made yet or not visible
1181     // yet. However, this is okay because the request is asynchronous and
1182     // we will see the new flag value the next time through. It's also
1183     // possible that the external suspend request is dropped after
1184     // we have checked is_external_suspend(), we will recheck its value
1185     // under SR_lock in java_suspend_self().
1186     return (_special_runtime_exit_condition != _no_async_condition) ||
1187             is_external_suspend() || is_deopt_suspend();
1188   }
1189 
1190   void set_pending_unsafe_access_error()          { _special_runtime_exit_condition = _async_unsafe_access_error; }
1191 
1192   inline void set_pending_async_exception(oop e);
1193 
1194   // Fast-locking support
1195   bool is_lock_owned(address adr) const;
1196 
1197   // Accessors for vframe array top
1198   // The linked list of vframe arrays are sorted on sp. This means when we
1199   // unpack the head must contain the vframe array to unpack.
1200   void set_vframe_array_head(vframeArray* value) { _vframe_array_head = value; }
1201   vframeArray* vframe_array_head() const         { return _vframe_array_head;  }
1202 
1203   // Side structure for deferring update of java frame locals until deopt occurs
1204   GrowableArray<jvmtiDeferredLocalVariableSet*>* deferred_locals() const { return _deferred_locals_updates; }
1205   void set_deferred_locals(GrowableArray<jvmtiDeferredLocalVariableSet *>* vf) { _deferred_locals_updates = vf; }
1206 
1207   // These only really exist to make debugging deopt problems simpler
1208 
1209   void set_vframe_array_last(vframeArray* value) { _vframe_array_last = value; }
1210   vframeArray* vframe_array_last() const         { return _vframe_array_last;  }
1211 
1212   // The special resourceMark used during deoptimization
1213 
1214   void set_deopt_mark(DeoptResourceMark* value)  { _deopt_mark = value; }
1215   DeoptResourceMark* deopt_mark(void)            { return _deopt_mark; }
1216 
1217   intptr_t* must_deopt_id()                      { return _must_deopt_id; }
1218   void     set_must_deopt_id(intptr_t* id)       { _must_deopt_id = id; }
1219   void     clear_must_deopt_id()                 { _must_deopt_id = NULL; }
1220 
1221   void set_deopt_nmethod(nmethod* nm)            { _deopt_nmethod = nm;   }
1222   nmethod* deopt_nmethod()                       { return _deopt_nmethod; }
1223 
1224   Method*    callee_target() const               { return _callee_target; }
1225   void set_callee_target  (Method* x)          { _callee_target   = x; }
1226 
1227   // Oop results of vm runtime calls
1228   oop  vm_result() const                         { return _vm_result; }
1229   void set_vm_result  (oop x)                    { _vm_result   = x; }
1230 
1231   Metadata*    vm_result_2() const               { return _vm_result_2; }
1232   void set_vm_result_2  (Metadata* x)          { _vm_result_2   = x; }
1233 
1234   MemRegion deferred_card_mark() const           { return _deferred_card_mark; }
1235   void set_deferred_card_mark(MemRegion mr)      { _deferred_card_mark = mr;   }
1236 
1237   // Exception handling for compiled methods
1238   oop      exception_oop() const                 { return _exception_oop; }
1239   address  exception_pc() const                  { return _exception_pc; }
1240   address  exception_handler_pc() const          { return _exception_handler_pc; }
1241   bool     is_method_handle_return() const       { return _is_method_handle_return == 1; }
1242 
1243   void set_exception_oop(oop o)                  { (void)const_cast<oop&>(_exception_oop = o); }
1244   void set_exception_pc(address a)               { _exception_pc = a; }
1245   void set_exception_handler_pc(address a)       { _exception_handler_pc = a; }
1246   void set_is_method_handle_return(bool value)   { _is_method_handle_return = value ? 1 : 0; }
1247 
1248   void clear_exception_oop_and_pc() {
1249     set_exception_oop(NULL);
1250     set_exception_pc(NULL);
1251   }
1252 
1253   // Stack overflow support
1254   inline size_t stack_available(address cur_sp);
1255   address stack_yellow_zone_base()
1256     { return (address)(stack_base() - (stack_size() - (stack_red_zone_size() + stack_yellow_zone_size()))); }
1257   size_t  stack_yellow_zone_size()
1258     { return StackYellowPages * os::vm_page_size(); }
1259   address stack_red_zone_base()
1260     { return (address)(stack_base() - (stack_size() - stack_red_zone_size())); }
1261   size_t stack_red_zone_size()
1262     { return StackRedPages * os::vm_page_size(); }
1263   bool in_stack_yellow_zone(address a)
1264     { return (a <= stack_yellow_zone_base()) && (a >= stack_red_zone_base()); }
1265   bool in_stack_red_zone(address a)
1266     { return (a <= stack_red_zone_base()) && (a >= (address)((intptr_t)stack_base() - stack_size())); }
1267 
1268   void create_stack_guard_pages();
1269   void remove_stack_guard_pages();
1270 
1271   void enable_stack_yellow_zone();
1272   void disable_stack_yellow_zone();
1273   void enable_stack_red_zone();
1274   void disable_stack_red_zone();
1275 
1276   inline bool stack_guard_zone_unused();
1277   inline bool stack_yellow_zone_disabled();
1278   inline bool stack_yellow_zone_enabled();
1279 
1280   // Attempt to reguard the stack after a stack overflow may have occurred.
1281   // Returns true if (a) guard pages are not needed on this thread, (b) the
1282   // pages are already guarded, or (c) the pages were successfully reguarded.
1283   // Returns false if there is not enough stack space to reguard the pages, in
1284   // which case the caller should unwind a frame and try again.  The argument
1285   // should be the caller's (approximate) sp.
1286   bool reguard_stack(address cur_sp);
1287   // Similar to above but see if current stackpoint is out of the guard area
1288   // and reguard if possible.
1289   bool reguard_stack(void);
1290 
1291   address stack_overflow_limit() { return _stack_overflow_limit; }
1292   void set_stack_overflow_limit() {
1293     _stack_overflow_limit = _stack_base - _stack_size +
1294                             ((StackShadowPages +
1295                               StackYellowPages +
1296                               StackRedPages) * os::vm_page_size());
1297   }
1298 
1299   // Misc. accessors/mutators
1300   void set_do_not_unlock(void)                   { _do_not_unlock_if_synchronized = true; }
1301   void clr_do_not_unlock(void)                   { _do_not_unlock_if_synchronized = false; }
1302   bool do_not_unlock(void)                       { return _do_not_unlock_if_synchronized; }
1303 
1304 #ifndef PRODUCT
1305   void record_jump(address target, address instr, const char* file, int line);
1306 #endif /* PRODUCT */
1307 
1308   // For assembly stub generation
1309   static ByteSize threadObj_offset()             { return byte_offset_of(JavaThread, _threadObj); }
1310 #ifndef PRODUCT
1311   static ByteSize jmp_ring_index_offset()        { return byte_offset_of(JavaThread, _jmp_ring_index); }
1312   static ByteSize jmp_ring_offset()              { return byte_offset_of(JavaThread, _jmp_ring); }
1313 #endif /* PRODUCT */
1314   static ByteSize jni_environment_offset()       { return byte_offset_of(JavaThread, _jni_environment); }
1315   static ByteSize last_Java_sp_offset() {
1316     return byte_offset_of(JavaThread, _anchor) + JavaFrameAnchor::last_Java_sp_offset();
1317   }
1318   static ByteSize last_Java_pc_offset() {
1319     return byte_offset_of(JavaThread, _anchor) + JavaFrameAnchor::last_Java_pc_offset();
1320   }
1321   static ByteSize frame_anchor_offset() {
1322     return byte_offset_of(JavaThread, _anchor);
1323   }
1324   static ByteSize callee_target_offset()         { return byte_offset_of(JavaThread, _callee_target); }
1325   static ByteSize vm_result_offset()             { return byte_offset_of(JavaThread, _vm_result); }
1326   static ByteSize vm_result_2_offset()           { return byte_offset_of(JavaThread, _vm_result_2); }
1327   static ByteSize thread_state_offset()          { return byte_offset_of(JavaThread, _thread_state); }
1328   static ByteSize saved_exception_pc_offset()    { return byte_offset_of(JavaThread, _saved_exception_pc); }
1329   static ByteSize osthread_offset()              { return byte_offset_of(JavaThread, _osthread); }
1330   static ByteSize exception_oop_offset()         { return byte_offset_of(JavaThread, _exception_oop); }
1331   static ByteSize exception_pc_offset()          { return byte_offset_of(JavaThread, _exception_pc); }
1332   static ByteSize exception_handler_pc_offset()  { return byte_offset_of(JavaThread, _exception_handler_pc); }
1333   static ByteSize stack_overflow_limit_offset()  { return byte_offset_of(JavaThread, _stack_overflow_limit); }
1334   static ByteSize is_method_handle_return_offset() { return byte_offset_of(JavaThread, _is_method_handle_return); }
1335   static ByteSize stack_guard_state_offset()     { return byte_offset_of(JavaThread, _stack_guard_state); }
1336   static ByteSize suspend_flags_offset()         { return byte_offset_of(JavaThread, _suspend_flags); }
1337 
1338   static ByteSize do_not_unlock_if_synchronized_offset() { return byte_offset_of(JavaThread, _do_not_unlock_if_synchronized); }
1339   static ByteSize should_post_on_exceptions_flag_offset() {
1340     return byte_offset_of(JavaThread, _should_post_on_exceptions_flag);
1341   }
1342 
1343 #if INCLUDE_ALL_GCS
1344   static ByteSize satb_mark_queue_offset()       { return byte_offset_of(JavaThread, _satb_mark_queue); }
1345   static ByteSize dirty_card_queue_offset()      { return byte_offset_of(JavaThread, _dirty_card_queue); }
1346 #endif // INCLUDE_ALL_GCS
1347 
1348   // Returns the jni environment for this thread
1349   JNIEnv* jni_environment()                      { return &_jni_environment; }
1350 
1351   static JavaThread* thread_from_jni_environment(JNIEnv* env) {
1352     JavaThread *thread_from_jni_env = (JavaThread*)((intptr_t)env - in_bytes(jni_environment_offset()));
1353     // Only return NULL if thread is off the thread list; starting to
1354     // exit should not return NULL.
1355     if (thread_from_jni_env->is_terminated()) {
1356        thread_from_jni_env->block_if_vm_exited();
1357        return NULL;
1358     } else {
1359        return thread_from_jni_env;
1360     }
1361   }
1362 
1363   // JNI critical regions. These can nest.
1364   bool in_critical()    { return _jni_active_critical > 0; }
1365   bool in_last_critical()  { return _jni_active_critical == 1; }
1366   void enter_critical() { assert(Thread::current() == this ||
1367                                  Thread::current()->is_VM_thread() && SafepointSynchronize::is_synchronizing(),
1368                                  "this must be current thread or synchronizing");
1369                           _jni_active_critical++; }
1370   void exit_critical()  { assert(Thread::current() == this,
1371                                  "this must be current thread");
1372                           _jni_active_critical--;
1373                           assert(_jni_active_critical >= 0,
1374                                  "JNI critical nesting problem?"); }
1375 
1376   // Checked JNI, is the programmer required to check for exceptions, specify which function name
1377   bool is_pending_jni_exception_check() const { return _pending_jni_exception_check_fn != NULL; }
1378   void clear_pending_jni_exception_check() { _pending_jni_exception_check_fn = NULL; }
1379   const char* get_pending_jni_exception_check() const { return _pending_jni_exception_check_fn; }
1380   void set_pending_jni_exception_check(const char* fn_name) { _pending_jni_exception_check_fn = (char*) fn_name; }
1381 
1382   // For deadlock detection
1383   int depth_first_number() { return _depth_first_number; }
1384   void set_depth_first_number(int dfn) { _depth_first_number = dfn; }
1385 
1386  private:
1387   void set_monitor_chunks(MonitorChunk* monitor_chunks) { _monitor_chunks = monitor_chunks; }
1388 
1389  public:
1390   MonitorChunk* monitor_chunks() const           { return _monitor_chunks; }
1391   void add_monitor_chunk(MonitorChunk* chunk);
1392   void remove_monitor_chunk(MonitorChunk* chunk);
1393   bool in_deopt_handler() const                  { return _in_deopt_handler > 0; }
1394   void inc_in_deopt_handler()                    { _in_deopt_handler++; }
1395   void dec_in_deopt_handler() {
1396     assert(_in_deopt_handler > 0, "mismatched deopt nesting");
1397     if (_in_deopt_handler > 0) { // robustness
1398       _in_deopt_handler--;
1399     }
1400   }
1401 
1402  private:
1403   void set_entry_point(ThreadFunction entry_point) { _entry_point = entry_point; }
1404 
1405  public:
1406 
1407   // Frame iteration; calls the function f for all frames on the stack
1408   void frames_do(void f(frame*, const RegisterMap*));
1409 
1410   // Memory operations
1411   void oops_do(OopClosure* f, CLDClosure* cld_f, CodeBlobClosure* cf);
1412 
1413   // Sweeper operations
1414   void nmethods_do(CodeBlobClosure* cf);
1415 
1416   // RedefineClasses Support
1417   void metadata_do(void f(Metadata*));
1418 
1419   // Misc. operations
1420   char* name() const { return (char*)get_thread_name(); }
1421   void print_on(outputStream* st) const;
1422   void print_value();
1423   void print_thread_state_on(outputStream* ) const      PRODUCT_RETURN;
1424   void print_thread_state() const                       PRODUCT_RETURN;
1425   void print_on_error(outputStream* st, char* buf, int buflen) const;
1426   void verify();
1427   const char* get_thread_name() const;
1428 private:
1429   // factor out low-level mechanics for use in both normal and error cases
1430   const char* get_thread_name_string(char* buf = NULL, int buflen = 0) const;
1431 public:
1432   const char* get_threadgroup_name() const;
1433   const char* get_parent_name() const;
1434 
1435   // Accessing frames
1436   frame last_frame() {
1437     _anchor.make_walkable(this);
1438     return pd_last_frame();
1439   }
1440   javaVFrame* last_java_vframe(RegisterMap* reg_map);
1441 
1442   // Returns method at 'depth' java or native frames down the stack
1443   // Used for security checks
1444   Klass* security_get_caller_class(int depth);
1445 
1446   // Print stack trace in external format
1447   void print_stack_on(outputStream* st);
1448   void print_stack() { print_stack_on(tty); }
1449 
1450   // Print stack traces in various internal formats
1451   void trace_stack()                             PRODUCT_RETURN;
1452   void trace_stack_from(vframe* start_vf)        PRODUCT_RETURN;
1453   void trace_frames()                            PRODUCT_RETURN;
1454   void trace_oops()                              PRODUCT_RETURN;
1455 
1456   // Print an annotated view of the stack frames
1457   void print_frame_layout(int depth = 0, bool validate_only = false) NOT_DEBUG_RETURN;
1458   void validate_frame_layout() {
1459     print_frame_layout(0, true);
1460   }
1461 
1462   // Returns the number of stack frames on the stack
1463   int depth() const;
1464 
1465   // Function for testing deoptimization
1466   void deoptimize();
1467   void make_zombies();
1468 
1469   void deoptimized_wrt_marked_nmethods();
1470 
1471   // Profiling operation (see fprofile.cpp)
1472  public:
1473    bool profile_last_Java_frame(frame* fr);
1474 
1475  private:
1476    ThreadProfiler* _thread_profiler;
1477  private:
1478    friend class FlatProfiler;                    // uses both [gs]et_thread_profiler.
1479    friend class FlatProfilerTask;                // uses get_thread_profiler.
1480    friend class ThreadProfilerMark;              // uses get_thread_profiler.
1481    ThreadProfiler* get_thread_profiler()         { return _thread_profiler; }
1482    ThreadProfiler* set_thread_profiler(ThreadProfiler* tp) {
1483      ThreadProfiler* result = _thread_profiler;
1484      _thread_profiler = tp;
1485      return result;
1486    }
1487 
1488  // NMT (Native memory tracking) support.
1489  // This flag helps NMT to determine if this JavaThread will be blocked
1490  // at safepoint. If not, ThreadCritical is needed for writing memory records.
1491  // JavaThread is only safepoint visible when it is in Threads' thread list,
1492  // it is not visible until it is added to the list and becomes invisible
1493  // once it is removed from the list.
1494  public:
1495   bool is_safepoint_visible() const { return _safepoint_visible; }
1496   void set_safepoint_visible(bool visible) { _safepoint_visible = visible; }
1497  private:
1498   bool _safepoint_visible;
1499 
1500   // Static operations
1501  public:
1502   // Returns the running thread as a JavaThread
1503   static inline JavaThread* current();
1504 
1505   // Returns the active Java thread.  Do not use this if you know you are calling
1506   // from a JavaThread, as it's slower than JavaThread::current.  If called from
1507   // the VMThread, it also returns the JavaThread that instigated the VMThread's
1508   // operation.  You may not want that either.
1509   static JavaThread* active();
1510 
1511   inline CompilerThread* as_CompilerThread();
1512 
1513  public:
1514   virtual void run();
1515   void thread_main_inner();
1516 
1517  private:
1518   // PRIVILEGED STACK
1519   PrivilegedElement*  _privileged_stack_top;
1520   GrowableArray<oop>* _array_for_gc;
1521  public:
1522 
1523   // Returns the privileged_stack information.
1524   PrivilegedElement* privileged_stack_top() const       { return _privileged_stack_top; }
1525   void set_privileged_stack_top(PrivilegedElement *e)   { _privileged_stack_top = e; }
1526   void register_array_for_gc(GrowableArray<oop>* array) { _array_for_gc = array; }
1527 
1528  public:
1529   // Thread local information maintained by JVMTI.
1530   void set_jvmti_thread_state(JvmtiThreadState *value)                           { _jvmti_thread_state = value; }
1531   // A JvmtiThreadState is lazily allocated. This jvmti_thread_state()
1532   // getter is used to get this JavaThread's JvmtiThreadState if it has
1533   // one which means NULL can be returned. JvmtiThreadState::state_for()
1534   // is used to get the specified JavaThread's JvmtiThreadState if it has
1535   // one or it allocates a new JvmtiThreadState for the JavaThread and
1536   // returns it. JvmtiThreadState::state_for() will return NULL only if
1537   // the specified JavaThread is exiting.
1538   JvmtiThreadState *jvmti_thread_state() const                                   { return _jvmti_thread_state; }
1539   static ByteSize jvmti_thread_state_offset()                                    { return byte_offset_of(JavaThread, _jvmti_thread_state); }
1540   void set_jvmti_get_loaded_classes_closure(JvmtiGetLoadedClassesClosure* value) { _jvmti_get_loaded_classes_closure = value; }
1541   JvmtiGetLoadedClassesClosure* get_jvmti_get_loaded_classes_closure() const     { return _jvmti_get_loaded_classes_closure; }
1542 
1543   // JVMTI PopFrame support
1544   // Setting and clearing popframe_condition
1545   // All of these enumerated values are bits. popframe_pending
1546   // indicates that a PopFrame() has been requested and not yet been
1547   // completed. popframe_processing indicates that that PopFrame() is in
1548   // the process of being completed. popframe_force_deopt_reexecution_bit
1549   // indicates that special handling is required when returning to a
1550   // deoptimized caller.
1551   enum PopCondition {
1552     popframe_inactive                      = 0x00,
1553     popframe_pending_bit                   = 0x01,
1554     popframe_processing_bit                = 0x02,
1555     popframe_force_deopt_reexecution_bit   = 0x04
1556   };
1557   PopCondition popframe_condition()                   { return (PopCondition) _popframe_condition; }
1558   void set_popframe_condition(PopCondition c)         { _popframe_condition = c; }
1559   void set_popframe_condition_bit(PopCondition c)     { _popframe_condition |= c; }
1560   void clear_popframe_condition()                     { _popframe_condition = popframe_inactive; }
1561   static ByteSize popframe_condition_offset()         { return byte_offset_of(JavaThread, _popframe_condition); }
1562   bool has_pending_popframe()                         { return (popframe_condition() & popframe_pending_bit) != 0; }
1563   bool popframe_forcing_deopt_reexecution()           { return (popframe_condition() & popframe_force_deopt_reexecution_bit) != 0; }
1564   void clear_popframe_forcing_deopt_reexecution()     { _popframe_condition &= ~popframe_force_deopt_reexecution_bit; }
1565 #ifdef CC_INTERP
1566   bool pop_frame_pending(void)                        { return ((_popframe_condition & popframe_pending_bit) != 0); }
1567   void clr_pop_frame_pending(void)                    { _popframe_condition = popframe_inactive; }
1568   bool pop_frame_in_process(void)                     { return ((_popframe_condition & popframe_processing_bit) != 0); }
1569   void set_pop_frame_in_process(void)                 { _popframe_condition |= popframe_processing_bit; }
1570   void clr_pop_frame_in_process(void)                 { _popframe_condition &= ~popframe_processing_bit; }
1571 #endif
1572 
1573  private:
1574   // Saved incoming arguments to popped frame.
1575   // Used only when popped interpreted frame returns to deoptimized frame.
1576   void*    _popframe_preserved_args;
1577   int      _popframe_preserved_args_size;
1578 
1579  public:
1580   void  popframe_preserve_args(ByteSize size_in_bytes, void* start);
1581   void* popframe_preserved_args();
1582   ByteSize popframe_preserved_args_size();
1583   WordSize popframe_preserved_args_size_in_words();
1584   void  popframe_free_preserved_args();
1585 
1586 
1587  private:
1588   JvmtiThreadState *_jvmti_thread_state;
1589   JvmtiGetLoadedClassesClosure* _jvmti_get_loaded_classes_closure;
1590 
1591   // Used by the interpreter in fullspeed mode for frame pop, method
1592   // entry, method exit and single stepping support. This field is
1593   // only set to non-zero by the VM_EnterInterpOnlyMode VM operation.
1594   // It can be set to zero asynchronously (i.e., without a VM operation
1595   // or a lock) so we have to be very careful.
1596   int               _interp_only_mode;
1597 
1598  public:
1599   // used by the interpreter for fullspeed debugging support (see above)
1600   static ByteSize interp_only_mode_offset() { return byte_offset_of(JavaThread, _interp_only_mode); }
1601   bool is_interp_only_mode()                { return (_interp_only_mode != 0); }
1602   int get_interp_only_mode()                { return _interp_only_mode; }
1603   void increment_interp_only_mode()         { ++_interp_only_mode; }
1604   void decrement_interp_only_mode()         { --_interp_only_mode; }
1605 
1606   // support for cached flag that indicates whether exceptions need to be posted for this thread
1607   // if this is false, we can avoid deoptimizing when events are thrown
1608   // this gets set to reflect whether jvmtiExport::post_exception_throw would actually do anything
1609  private:
1610   int    _should_post_on_exceptions_flag;
1611 
1612  public:
1613   int   should_post_on_exceptions_flag()  { return _should_post_on_exceptions_flag; }
1614   void  set_should_post_on_exceptions_flag(int val)  { _should_post_on_exceptions_flag = val; }
1615 
1616  private:
1617   ThreadStatistics *_thread_stat;
1618 
1619  public:
1620   ThreadStatistics* get_thread_stat() const    { return _thread_stat; }
1621 
1622   // Return a blocker object for which this thread is blocked parking.
1623   oop current_park_blocker();
1624 
1625  private:
1626   static size_t _stack_size_at_create;
1627 
1628  public:
1629   static inline size_t stack_size_at_create(void) {
1630     return _stack_size_at_create;
1631   }
1632   static inline void set_stack_size_at_create(size_t value) {
1633     _stack_size_at_create = value;
1634   }
1635 
1636 #if INCLUDE_ALL_GCS
1637   // SATB marking queue support
1638   ObjPtrQueue& satb_mark_queue() { return _satb_mark_queue; }
1639   static SATBMarkQueueSet& satb_mark_queue_set() {
1640     return _satb_mark_queue_set;
1641   }
1642 
1643   // Dirty card queue support
1644   DirtyCardQueue& dirty_card_queue() { return _dirty_card_queue; }
1645   static DirtyCardQueueSet& dirty_card_queue_set() {
1646     return _dirty_card_queue_set;
1647   }
1648 #endif // INCLUDE_ALL_GCS
1649 
1650   // This method initializes the SATB and dirty card queues before a
1651   // JavaThread is added to the Java thread list. Right now, we don't
1652   // have to do anything to the dirty card queue (it should have been
1653   // activated when the thread was created), but we have to activate
1654   // the SATB queue if the thread is created while a marking cycle is
1655   // in progress. The activation / de-activation of the SATB queues at
1656   // the beginning / end of a marking cycle is done during safepoints
1657   // so we have to make sure this method is called outside one to be
1658   // able to safely read the active field of the SATB queue set. Right
1659   // now, it is called just before the thread is added to the Java
1660   // thread list in the Threads::add() method. That method is holding
1661   // the Threads_lock which ensures we are outside a safepoint. We
1662   // cannot do the obvious and set the active field of the SATB queue
1663   // when the thread is created given that, in some cases, safepoints
1664   // might happen between the JavaThread constructor being called and the
1665   // thread being added to the Java thread list (an example of this is
1666   // when the structure for the DestroyJavaVM thread is created).
1667 #if INCLUDE_ALL_GCS
1668   void initialize_queues();
1669 #else  // INCLUDE_ALL_GCS
1670   void initialize_queues() { }
1671 #endif // INCLUDE_ALL_GCS
1672 
1673   // Machine dependent stuff
1674 #ifdef TARGET_OS_ARCH_linux_x86
1675 # include "thread_linux_x86.hpp"
1676 #endif
1677 #ifdef TARGET_OS_ARCH_linux_sparc
1678 # include "thread_linux_sparc.hpp"
1679 #endif
1680 #ifdef TARGET_OS_ARCH_linux_zero
1681 # include "thread_linux_zero.hpp"
1682 #endif
1683 #ifdef TARGET_OS_ARCH_solaris_x86
1684 # include "thread_solaris_x86.hpp"
1685 #endif
1686 #ifdef TARGET_OS_ARCH_solaris_sparc
1687 # include "thread_solaris_sparc.hpp"
1688 #endif
1689 #ifdef TARGET_OS_ARCH_windows_x86
1690 # include "thread_windows_x86.hpp"
1691 #endif
1692 #ifdef TARGET_OS_ARCH_linux_arm
1693 # include "thread_linux_arm.hpp"
1694 #endif
1695 #ifdef TARGET_OS_ARCH_linux_ppc
1696 # include "thread_linux_ppc.hpp"
1697 #endif
1698 #ifdef TARGET_OS_ARCH_aix_ppc
1699 # include "thread_aix_ppc.hpp"
1700 #endif
1701 #ifdef TARGET_OS_ARCH_bsd_x86
1702 # include "thread_bsd_x86.hpp"
1703 #endif
1704 #ifdef TARGET_OS_ARCH_bsd_zero
1705 # include "thread_bsd_zero.hpp"
1706 #endif
1707 
1708 
1709  public:
1710   void set_blocked_on_compilation(bool value) {
1711     _blocked_on_compilation = value;
1712   }
1713 
1714   bool blocked_on_compilation() {
1715     return _blocked_on_compilation;
1716   }
1717  protected:
1718   bool         _blocked_on_compilation;
1719 
1720 
1721   // JSR166 per-thread parker
1722 private:
1723   Parker*    _parker;
1724 public:
1725   Parker*     parker() { return _parker; }
1726 
1727   // Biased locking support
1728 private:
1729   GrowableArray<MonitorInfo*>* _cached_monitor_info;
1730 public:
1731   GrowableArray<MonitorInfo*>* cached_monitor_info() { return _cached_monitor_info; }
1732   void set_cached_monitor_info(GrowableArray<MonitorInfo*>* info) { _cached_monitor_info = info; }
1733 
1734   // clearing/querying jni attach status
1735   bool is_attaching_via_jni() const { return _jni_attach_state == _attaching_via_jni; }
1736   bool has_attached_via_jni() const { return is_attaching_via_jni() || _jni_attach_state == _attached_via_jni; }
1737   inline void set_done_attaching_via_jni();
1738 private:
1739   // This field is used to determine if a thread has claimed
1740   // a par_id: it is UINT_MAX if the thread has not claimed a par_id;
1741   // otherwise its value is the par_id that has been claimed.
1742   uint _claimed_par_id;
1743 public:
1744   uint get_claimed_par_id() { return _claimed_par_id; }
1745   void set_claimed_par_id(uint id) { _claimed_par_id = id; }
1746 };
1747 
1748 // Inline implementation of JavaThread::current
1749 inline JavaThread* JavaThread::current() {
1750   Thread* thread = ThreadLocalStorage::thread();
1751   assert(thread != NULL && thread->is_Java_thread(), "just checking");
1752   return (JavaThread*)thread;
1753 }
1754 
1755 inline CompilerThread* JavaThread::as_CompilerThread() {
1756   assert(is_Compiler_thread(), "just checking");
1757   return (CompilerThread*)this;
1758 }
1759 
1760 // A thread used for Compilation.
1761 class CompilerThread : public JavaThread {
1762   friend class VMStructs;
1763  private:
1764   CompilerCounters* _counters;
1765 
1766   ciEnv*            _env;
1767   CompileLog*       _log;
1768   CompileTask*      _task;
1769   CompileQueue*     _queue;
1770   BufferBlob*       _buffer_blob;
1771 
1772   nmethod*          _scanned_nmethod;  // nmethod being scanned by the sweeper
1773   AbstractCompiler* _compiler;
1774 
1775  public:
1776 
1777   static CompilerThread* current();
1778 
1779   CompilerThread(CompileQueue* queue, CompilerCounters* counters);
1780 
1781   bool is_Compiler_thread() const                { return true; }
1782   // Hide this compiler thread from external view.
1783   bool is_hidden_from_external_view() const      { return true; }
1784 
1785   void set_compiler(AbstractCompiler* c)         { _compiler = c; }
1786   AbstractCompiler* compiler() const             { return _compiler; }
1787 
1788   CompileQueue* queue()        const             { return _queue; }
1789   CompilerCounters* counters() const             { return _counters; }
1790 
1791   // Get/set the thread's compilation environment.
1792   ciEnv*        env()                            { return _env; }
1793   void          set_env(ciEnv* env)              { _env = env; }
1794 
1795   BufferBlob*   get_buffer_blob() const          { return _buffer_blob; }
1796   void          set_buffer_blob(BufferBlob* b)   { _buffer_blob = b; };
1797 
1798   // Get/set the thread's logging information
1799   CompileLog*   log()                            { return _log; }
1800   void          init_log(CompileLog* log) {
1801     // Set once, for good.
1802     assert(_log == NULL, "set only once");
1803     _log = log;
1804   }
1805 
1806   // GC support
1807   // Apply "f->do_oop" to all root oops in "this".
1808   // Apply "cf->do_code_blob" (if !NULL) to all code blobs active in frames
1809   void oops_do(OopClosure* f, CLDClosure* cld_f, CodeBlobClosure* cf);
1810 
1811 #ifndef PRODUCT
1812 private:
1813   IdealGraphPrinter *_ideal_graph_printer;
1814 public:
1815   IdealGraphPrinter *ideal_graph_printer()                       { return _ideal_graph_printer; }
1816   void set_ideal_graph_printer(IdealGraphPrinter *n)             { _ideal_graph_printer = n; }
1817 #endif
1818 
1819   // Get/set the thread's current task
1820   CompileTask*  task()                           { return _task; }
1821   void          set_task(CompileTask* task)      { _task = task; }
1822 
1823   // Track the nmethod currently being scanned by the sweeper
1824   void          set_scanned_nmethod(nmethod* nm) {
1825     assert(_scanned_nmethod == NULL || nm == NULL, "should reset to NULL before writing a new value");
1826     _scanned_nmethod = nm;
1827   }
1828 };
1829 
1830 inline CompilerThread* CompilerThread::current() {
1831   return JavaThread::current()->as_CompilerThread();
1832 }
1833 
1834 // The active thread queue. It also keeps track of the current used
1835 // thread priorities.
1836 class Threads: AllStatic {
1837   friend class VMStructs;
1838  private:
1839   static JavaThread* _thread_list;
1840   static int         _number_of_threads;
1841   static int         _number_of_non_daemon_threads;
1842   static int         _return_code;
1843 #ifdef ASSERT
1844   static bool        _vm_complete;
1845 #endif
1846 
1847   static void initialize_java_lang_classes(JavaThread* main_thread, TRAPS);
1848   static void initialize_jsr292_core_classes(TRAPS);
1849  public:
1850   // Thread management
1851   // force_daemon is a concession to JNI, where we may need to add a
1852   // thread to the thread list before allocating its thread object
1853   static void add(JavaThread* p, bool force_daemon = false);
1854   static void remove(JavaThread* p);
1855   static bool includes(JavaThread* p);
1856   static JavaThread* first()                     { return _thread_list; }
1857   static void threads_do(ThreadClosure* tc);
1858 
1859   // Initializes the vm and creates the vm thread
1860   static jint create_vm(JavaVMInitArgs* args, bool* canTryAgain);
1861   static void convert_vm_init_libraries_to_agents();
1862   static void create_vm_init_libraries();
1863   static void create_vm_init_agents();
1864   static void shutdown_vm_agents();
1865   static bool destroy_vm();
1866   // Supported VM versions via JNI
1867   // Includes JNI_VERSION_1_1
1868   static jboolean is_supported_jni_version_including_1_1(jint version);
1869   // Does not include JNI_VERSION_1_1
1870   static jboolean is_supported_jni_version(jint version);
1871 
1872   // Garbage collection
1873   static void follow_other_roots(void f(oop*));
1874 
1875   // Apply "f->do_oop" to all root oops in all threads.
1876   // This version may only be called by sequential code.
1877   static void oops_do(OopClosure* f, CLDClosure* cld_f, CodeBlobClosure* cf);
1878   // This version may be called by sequential or parallel code.
1879   static void possibly_parallel_oops_do(OopClosure* f, CLDClosure* cld_f, CodeBlobClosure* cf);
1880   // This creates a list of GCTasks, one per thread.
1881   static void create_thread_roots_tasks(GCTaskQueue* q);
1882   // This creates a list of GCTasks, one per thread, for marking objects.
1883   static void create_thread_roots_marking_tasks(GCTaskQueue* q);
1884 
1885   // Apply "f->do_oop" to roots in all threads that
1886   // are part of compiled frames
1887   static void compiled_frame_oops_do(OopClosure* f, CodeBlobClosure* cf);
1888 
1889   static void convert_hcode_pointers();
1890   static void restore_hcode_pointers();
1891 
1892   // Sweeper
1893   static void nmethods_do(CodeBlobClosure* cf);
1894 
1895   // RedefineClasses support
1896   static void metadata_do(void f(Metadata*));
1897 
1898 #ifdef ASSERT
1899   static bool is_vm_complete() { return _vm_complete; }
1900 #endif
1901 
1902   // Verification
1903   static void verify();
1904   static void print_on(outputStream* st, bool print_stacks, bool internal_format, bool print_concurrent_locks);
1905   static void print(bool print_stacks, bool internal_format) {
1906     // this function is only used by debug.cpp
1907     print_on(tty, print_stacks, internal_format, false /* no concurrent lock printed */);
1908   }
1909   static void print_on_error(outputStream* st, Thread* current, char* buf, int buflen);
1910 
1911   // Get Java threads that are waiting to enter a monitor. If doLock
1912   // is true, then Threads_lock is grabbed as needed. Otherwise, the
1913   // VM needs to be at a safepoint.
1914   static GrowableArray<JavaThread*>* get_pending_threads(int count,
1915     address monitor, bool doLock);
1916 
1917   // Get owning Java thread from the monitor's owner field. If doLock
1918   // is true, then Threads_lock is grabbed as needed. Otherwise, the
1919   // VM needs to be at a safepoint.
1920   static JavaThread *owning_thread_from_monitor_owner(address owner,
1921     bool doLock);
1922 
1923   // Number of threads on the active threads list
1924   static int number_of_threads()                 { return _number_of_threads; }
1925   // Number of non-daemon threads on the active threads list
1926   static int number_of_non_daemon_threads()      { return _number_of_non_daemon_threads; }
1927 
1928   // Deoptimizes all frames tied to marked nmethods
1929   static void deoptimized_wrt_marked_nmethods();
1930 
1931 };
1932 
1933 
1934 // Thread iterator
1935 class ThreadClosure: public StackObj {
1936  public:
1937   virtual void do_thread(Thread* thread) = 0;
1938 };
1939 
1940 class SignalHandlerMark: public StackObj {
1941 private:
1942   Thread* _thread;
1943 public:
1944   SignalHandlerMark(Thread* t) {
1945     _thread = t;
1946     if (_thread) _thread->enter_signal_handler();
1947   }
1948   ~SignalHandlerMark() {
1949     if (_thread) _thread->leave_signal_handler();
1950     _thread = NULL;
1951   }
1952 };
1953 
1954 
1955 #endif // SHARE_VM_RUNTIME_THREAD_HPP