Ziele Untersuchung
mit Columbo Integrität von
Datenbanken Interaktion und
Portierbarkeit Ergonomie der
Schnittstellen

Angebot Produkte Projekt Beratung

Mittel Analytik Modellierung Sprachen Algebra Logik Hardware Denken Kreativität

Zusammenhänge Gesellschaft Wirtschaft Branche Firma


products/sources/formale Sprachen/Java/Openjdk/src/hotspot/share/runtime/ (Sun/Oracle ^©) Datei vom 13.11.2022 mit Größe 24 kB

Quelle thread.hpp Sprache: C

/*
* Copyright (c) 1997, 2022, Oracle and/or its affiliates. All rights reserved.
* Copyright (c) 2021, Azul Systems, Inc. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
* or visit www.oracle.com if you need additional information or have any
* questions.
*
*/

#ifndef SHARE_RUNTIME_THREAD_HPP
#define SHARE_RUNTIME_THREAD_HPP

#include "jni.h"
#include "gc/shared/gcThreadLocalData.hpp"
#include "gc/shared/threadLocalAllocBuffer.hpp"
#include "memory/allocation.hpp"
#include "runtime/atomic.hpp"
#include "runtime/globals.hpp"
#include "runtime/os.hpp"
#include "runtime/threadHeapSampler.hpp"
#include "runtime/threadLocalStorage.hpp"
#include "runtime/threadStatisticalInfo.hpp"
#include "runtime/unhandledOops.hpp"
#include "utilities/globalDefinitions.hpp"
#include "utilities/macros.hpp"
#if INCLUDE_JFR
#include "jfr/support/jfrThreadExtension.hpp"
#endif

class HandleArea;
class HandleMark;
class ICRefillVerifier;
class JvmtiRawMonitor;
class Metadata;
class OSThread;
class ParkEvent;
class ResourceArea;
class SafeThreadsListPtr;
class ThreadClosure;
class ThreadsList;
class ThreadsSMRSupport;

class OopClosure;
class CodeBlobClosure;

DEBUG_ONLY(class ResourceMark;)

class WorkerThread;

class JavaThread;

// Class hierarchy
// - Thread
//   - JavaThread
//     - various subclasses eg CompilerThread, ServiceThread
//   - NonJavaThread
//     - NamedThread
//       - VMThread
//       - ConcurrentGCThread
//       - WorkerThread
//     - WatcherThread
//     - JfrThreadSampler
//     - LogAsyncWriter
//
// All Thread subclasses must be either JavaThread or NonJavaThread.
// This means !t->is_Java_thread() iff t is a NonJavaThread, or t is
// a partially constructed/destroyed Thread.

// Thread execution sequence and actions:
// All threads:
//  - thread_native_entry  // per-OS native entry point
//    - stack initialization
//    - other OS-level initialization (signal masks etc)
//    - handshake with creating thread (if not started suspended)
//    - this->call_run()  // common shared entry point
//      - shared common initialization
//      - this->pre_run()  // virtual per-thread-type initialization
//      - this->run()      // virtual per-thread-type "main" logic
//      - shared common tear-down
//      - this->post_run()  // virtual per-thread-type tear-down
//      - // 'this' no longer referenceable
//    - OS-level tear-down (minimal)
//    - final logging
//
// For JavaThread:
//   - this->run()  // virtual but not normally overridden
//     - this->thread_main_inner()  // extra call level to ensure correct stack calculations
//       - this->entry_point()  // set differently for each kind of JavaThread

class Thread: public ThreadShadow {
  friend class VMStructs;
  friend class JVMCIVMStructs;
private:

#ifndef USE_LIBRARY_BASED_TLS_ONLY
  // Current thread is maintained as a thread-local variable
  static THREAD_LOCAL Thread* _thr_current;
#endif

  // On AArch64, the high order 32 bits are used by a "patching epoch" number
  // which reflects if this thread has executed the required fences, after
  // an nmethod gets disarmed. The low order 32 bit denote the disarm value.
  uint64_t _nmethod_disarm_value;

public:
  void set_nmethod_disarm_value(int value) {
    _nmethod_disarm_value = (uint64_t)(uint32_t)value;
  }

  static ByteSize nmethod_disarmed_offset() {
    ByteSize offset = byte_offset_of(Thread, _nmethod_disarm_value);
    // At least on x86_64, nmethod entry barrier encodes disarmed value offset
    // in instruction as disp8 immed
    assert(in_bytes(offset) < 128, "Offset >= 128");
    return offset;
  }

private:
  // Thread local data area available to the GC. The internal
  // structure and contents of this data area is GC-specific.
  // Only GC and GC barrier code should access this data area.
  GCThreadLocalData _gc_data;

public:
  static ByteSize gc_data_offset() {
    return byte_offset_of(Thread, _gc_data);
  }

  template <typename T> T* gc_data() {
    STATIC_ASSERT(sizeof(T) <= sizeof(_gc_data));
    return reinterpret_cast<T*>(&_gc_data);
  }

  // Exception handling
  // (Note: _pending_exception and friends are in ThreadShadow)
  //oop       _pending_exception;                // pending exception for current thread
  // const char* _exception_file;                   // file information for exception (debugging only)
  // int         _exception_line;                   // line information for exception (debugging only)
protected:

  DEBUG_ONLY(static Thread* _starting_thread;)

  // JavaThread lifecycle support:
  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
  friend class ScanHazardPtrGatherProtectedThreadsClosure;  // for cmpxchg_threads_hazard_ptr(), get_threads_hazard_ptr(), is_hazard_ptr_tagged() access
  friend class ScanHazardPtrGatherThreadsListClosure;  // for get_threads_hazard_ptr(), untag_hazard_ptr() access
  friend class ScanHazardPtrPrintMatchingThreadsClosure;  // for get_threads_hazard_ptr(), is_hazard_ptr_tagged() access
  friend class ThreadsSMRSupport;  // for _nested_threads_hazard_ptr_cnt, _threads_hazard_ptr, _threads_list_ptr access
  friend class ThreadsListHandleTest;  // for _nested_threads_hazard_ptr_cnt, _threads_hazard_ptr, _threads_list_ptr access
  friend class ValidateHazardPtrsClosure;  // for get_threads_hazard_ptr(), untag_hazard_ptr() access

  ThreadsList* volatile _threads_hazard_ptr;
  SafeThreadsListPtr*   _threads_list_ptr;
  ThreadsList*          cmpxchg_threads_hazard_ptr(ThreadsList* exchange_value, ThreadsList* compare_value);
  ThreadsList*          get_threads_hazard_ptr() const;
  void                  set_threads_hazard_ptr(ThreadsList* new_list);
  static bool           is_hazard_ptr_tagged(ThreadsList* list) {
    return (intptr_t(list) & intptr_t(1)) == intptr_t(1);
  }
  static ThreadsList*   tag_hazard_ptr(ThreadsList* list) {
    return (ThreadsList*)(intptr_t(list) | intptr_t(1));
  }
  static ThreadsList*   untag_hazard_ptr(ThreadsList* list) {
    return (ThreadsList*)(intptr_t(list) & ~intptr_t(1));
  }
  // This field is enabled via -XX:+EnableThreadSMRStatistics:
  uint _nested_threads_hazard_ptr_cnt;
  void dec_nested_threads_hazard_ptr_cnt() {
    assert(_nested_threads_hazard_ptr_cnt != 0, "mismatched {dec,inc}_nested_threads_hazard_ptr_cnt()");
    _nested_threads_hazard_ptr_cnt--;
  }
  void inc_nested_threads_hazard_ptr_cnt() {
    _nested_threads_hazard_ptr_cnt++;
  }
  uint nested_threads_hazard_ptr_cnt() {
    return _nested_threads_hazard_ptr_cnt;
  }

public:
  // Is the target JavaThread protected by the calling Thread or by some other
  // mechanism?
  static bool is_JavaThread_protected(const JavaThread* target);
  // Is the target JavaThread protected by a ThreadsListHandle (TLH) associated
  // with the calling Thread?
  static bool is_JavaThread_protected_by_TLH(const JavaThread* target);

  void* operator new(size_t size) throw() { return allocate(size, true); }
  void* operator new(size_t size, const std::nothrow_t& nothrow_constant) throw() {
    return allocate(size, false); }
  void  operator delete(void* p);

protected:
  static void* allocate(size_t size, bool throw_excpt, MEMFLAGS flags = mtThread);

private:
  DEBUG_ONLY(bool _suspendible_thread;)

public:
  // Determines if a heap allocation failure will be retried
  // (e.g., by deoptimizing and re-executing in the interpreter).
  // In this case, the failed allocation must raise
  // Universe::out_of_memory_error_retry() and omit side effects
  // such as JVMTI events and handling -XX:+HeapDumpOnOutOfMemoryError
  // and -XX:OnOutOfMemoryError.
  virtual bool in_retryable_allocation() const { return false; }

#ifdef ASSERT
  void set_suspendible_thread() {
    _suspendible_thread = true;
  }

  void clear_suspendible_thread() {
    _suspendible_thread = false;
  }

  bool is_suspendible_thread() { return _suspendible_thread; }
#endif

private:
  // Point to the last handle mark
  HandleMark* _last_handle_mark;

  // Claim value for parallel iteration over threads.
  uintx _threads_do_token;

  // Support for GlobalCounter
private:
  volatile uintx _rcu_counter;
public:
  volatile uintx* get_rcu_counter() {
    return &_rcu_counter;
  }

public:
  void set_last_handle_mark(HandleMark* mark)   { _last_handle_mark = mark; }
  HandleMark* last_handle_mark() const          { return _last_handle_mark; }
private:

#ifdef ASSERT
  ICRefillVerifier* _missed_ic_stub_refill_verifier;

public:
  ICRefillVerifier* missed_ic_stub_refill_verifier() {
    return _missed_ic_stub_refill_verifier;
  }

  void set_missed_ic_stub_refill_verifier(ICRefillVerifier* verifier) {
    _missed_ic_stub_refill_verifier = verifier;
  }
#endif // ASSERT

private:
  // Used by SkipGCALot class.
  NOT_PRODUCT(bool _skip_gcalot;)               // Should we elide gc-a-lot?

  friend class GCLocker;

private:
  ThreadLocalAllocBuffer _tlab;                 // Thread-local eden
  jlong _allocated_bytes;                       // Cumulative number of bytes allocated on
                                                // the Java heap
  ThreadHeapSampler _heap_sampler;              // For use when sampling the memory.

  ThreadStatisticalInfo _statistical_info;      // Statistics about the thread

  JFR_ONLY(DEFINE_THREAD_LOCAL_FIELD_JFR;)      // Thread-local data for jfr

  JvmtiRawMonitor* _current_pending_raw_monitor; // JvmtiRawMonitor this thread
                                                 // is waiting to lock
public:
  // Constructor
  Thread();
  virtual ~Thread() = 0;        // Thread is abstract.

  // Manage Thread::current()
  void initialize_thread_current();
  static void clear_thread_current(); // TLS cleanup needed before threads terminate

protected:
  // To be implemented by children.
  virtual void run() = 0;
  virtual void pre_run() = 0;
  virtual void post_run() = 0;  // Note: Thread must not be deleted prior to calling this!

#ifdef ASSERT
  enum RunState {
    PRE_CALL_RUN,
    CALL_RUN,
    PRE_RUN,
    RUN,
    POST_RUN
    // POST_CALL_RUN - can't define this one as 'this' may be deleted when we want to set it
  };
  RunState _run_state;  // for lifecycle checks
#endif

public:
  // invokes <ChildThreadClass>::run(), with common preparations and cleanups.
  void call_run();

  // Testers
  virtual bool is_VM_thread()       const            { return false; }
  virtual bool is_Java_thread()     const            { return false; }
  virtual bool is_Compiler_thread() const            { return false; }
  virtual bool is_service_thread() const             { return false; }
  virtual bool is_hidden_from_external_view() const  { return false; }
  virtual bool is_jvmti_agent_thread() const         { return false; }
  virtual bool is_Watcher_thread() const             { return false; }
  virtual bool is_ConcurrentGC_thread() const        { return false; }
  virtual bool is_Named_thread() const               { return false; }
  virtual bool is_Worker_thread() const              { return false; }
  virtual bool is_JfrSampler_thread() const          { return false; }

  // Can this thread make Java upcalls
  virtual bool can_call_java() const                 { return false; }

  // Is this a JavaThread that is on the VM's current ThreadsList?
  // If so it must participate in the safepoint protocol.
  virtual bool is_active_Java_thread() const         { return false; }

  // All threads are given names. For singleton subclasses we can
  // just hard-wire the known name of the instance. JavaThreads and
  // NamedThreads support multiple named instances, and dynamic
  // changing of the name of an instance.
  virtual const char* name() const { return "Unknown thread"; }

  // A thread's type name is also made available for debugging
  // and logging.
  virtual const char* type_name() const { return "Thread"; }

  // Returns the current thread (ASSERTS if NULL)
  static inline Thread* current();
  // Returns the current thread, or NULL if not attached
  static inline Thread* current_or_null();
  // Returns the current thread, or NULL if not attached, and is
  // safe for use from signal-handlers
  static inline Thread* current_or_null_safe();

  // Common thread operations
#ifdef ASSERT
  static void check_for_dangling_thread_pointer(Thread *thread);
#endif
  static void set_priority(Thread* thread, ThreadPriority priority);
  static void start(Thread* thread);

  void set_native_thread_name(const char *name) {
    assert(Thread::current() == this, "set_native_thread_name can only be called on the current thread");
    os::set_native_thread_name(name);
  }

  // Support for Unhandled Oop detection
  // Add the field for both, fastdebug and debug, builds to keep
  // Thread's fields layout the same.
  // Note: CHECK_UNHANDLED_OOPS is defined only for fastdebug build.
#ifdef CHECK_UNHANDLED_OOPS
private:
  UnhandledOops* _unhandled_oops;
#elif defined(ASSERT)
private:
  void* _unhandled_oops;
#endif
#ifdef CHECK_UNHANDLED_OOPS
public:
  UnhandledOops* unhandled_oops() { return _unhandled_oops; }
  // Mark oop safe for gc.  It may be stack allocated but won't move.
  void allow_unhandled_oop(oop *op) {
    if (CheckUnhandledOops) unhandled_oops()->allow_unhandled_oop(op);
  }
  // Clear oops at safepoint so crashes point to unhandled oop violator
  void clear_unhandled_oops() {
    if (CheckUnhandledOops) unhandled_oops()->clear_unhandled_oops();
  }
#endif // CHECK_UNHANDLED_OOPS

public:
#ifndef PRODUCT
  bool skip_gcalot()           { return _skip_gcalot; }
  void set_skip_gcalot(bool v) { _skip_gcalot = v;    }
#endif

  // Resource area
  ResourceArea* resource_area() const            { return _resource_area; }
  void set_resource_area(ResourceArea* area)     { _resource_area = area; }

  OSThread* osthread() const                     { return _osthread;   }
  void set_osthread(OSThread* thread)            { _osthread = thread; }

  // Internal handle support
  HandleArea* handle_area() const                { return _handle_area; }
  void set_handle_area(HandleArea* area)         { _handle_area = area; }

  GrowableArray<Metadata*>* metadata_handles() const          { return _metadata_handles; }
  void set_metadata_handles(GrowableArray<Metadata*>* handles){ _metadata_handles = handles; }

  // Thread-Local Allocation Buffer (TLAB) support
  ThreadLocalAllocBuffer& tlab()                 { return _tlab; }
  void initialize_tlab();

  jlong allocated_bytes()               { return _allocated_bytes; }
  void set_allocated_bytes(jlong value) { _allocated_bytes = value; }
  void incr_allocated_bytes(jlong size) { _allocated_bytes += size; }
  inline jlong cooked_allocated_bytes();

  ThreadHeapSampler& heap_sampler()     { return _heap_sampler; }

  ThreadStatisticalInfo& statistical_info() { return _statistical_info; }

  JFR_ONLY(DEFINE_THREAD_LOCAL_ACCESSOR_JFR;)

  // For tracking the Jvmti raw monitor the thread is pending on.
  JvmtiRawMonitor* current_pending_raw_monitor() {
    return _current_pending_raw_monitor;
  }
  void set_current_pending_raw_monitor(JvmtiRawMonitor* monitor) {
    _current_pending_raw_monitor = monitor;
  }

  // GC support
  // Apply "f->do_oop" to all root oops in "this".
  //   Used by JavaThread::oops_do.
  // Apply "cf->do_code_blob" (if !NULL) to all code blobs active in frames
  virtual void oops_do_no_frames(OopClosure* f, CodeBlobClosure* cf);
  virtual void oops_do_frames(OopClosure* f, CodeBlobClosure* cf) {}
  void oops_do(OopClosure* f, CodeBlobClosure* cf);

  // Handles the parallel case for claim_threads_do.
private:
  bool claim_par_threads_do(uintx claim_token);
public:
  // Requires that "claim_token" is that of the current iteration.
  // If "is_par" is false, sets the token of "this" to
  // "claim_token", and returns "true".  If "is_par" is true,
  // uses an atomic instruction to set the current thread's token to
  // "claim_token", if it is not already.  Returns "true" iff the
  // calling thread does the update, this indicates that the calling thread
  // has claimed the thread in the current iteration.
  bool claim_threads_do(bool is_par, uintx claim_token) {
    if (!is_par) {
      _threads_do_token = claim_token;
      return true;
    } else {
      return claim_par_threads_do(claim_token);
    }
  }

  uintx threads_do_token() const { return _threads_do_token; }

  // jvmtiRedefineClasses support
  void metadata_handles_do(void f(Metadata*));

private:
  // Check if address is within the given range of this thread's
  // stack:  stack_base() > adr >/>= limit
  // The check is inclusive of limit if passed true, else exclusive.
  bool is_in_stack_range(address adr, address limit, bool inclusive) const {
    assert(stack_base() > limit && limit >= stack_end(), "limit is outside of stack");
    return stack_base() > adr && (inclusive ? adr >= limit : adr > limit);
  }

public:
  // Used by fast lock support
  virtual bool is_lock_owned(address adr) const;

  // Check if address is within the given range of this thread's
  // stack:  stack_base() > adr >= limit
  bool is_in_stack_range_incl(address adr, address limit) const {
    return is_in_stack_range(adr, limit, true);
  }

  // Check if address is within the given range of this thread's
  // stack:  stack_base() > adr > limit
  bool is_in_stack_range_excl(address adr, address limit) const {
    return is_in_stack_range(adr, limit, false);
  }

  // Check if address is in the stack mapped to this thread. Used mainly in
  // error reporting (so has to include guard zone) and frame printing.
  // Expects _stack_base to be initialized - checked with assert.
  bool is_in_full_stack_checked(address adr) const {
    return is_in_stack_range_incl(adr, stack_end());
  }

  // Like is_in_full_stack_checked but without the assertions as this
  // may be called in a thread before _stack_base is initialized.
  bool is_in_full_stack(address adr) const {
    address stack_end = _stack_base - _stack_size;
    return _stack_base > adr && adr >= stack_end;
  }

  // Check if address is in the live stack of this thread (not just for locks).
  // Warning: can only be called by the current thread on itself.
  bool is_in_live_stack(address adr) const {
    assert(Thread::current() == this, "is_in_live_stack can only be called from current thread");
    return is_in_stack_range_incl(adr, os::current_stack_pointer());
  }

  // Sets this thread as starting thread. Returns failure if thread
  // creation fails due to lack of memory, too many threads etc.
  bool set_as_starting_thread();

protected:
  // OS data associated with the thread
  OSThread* _osthread;  // Platform-specific thread information

  // Thread local resource area for temporary allocation within the VM
  ResourceArea* _resource_area;

  DEBUG_ONLY(ResourceMark* _current_resource_mark;)

  // Thread local handle area for allocation of handles within the VM
  HandleArea* _handle_area;
  GrowableArray<Metadata*>* _metadata_handles;

  // Support for stack overflow handling, get_thread, etc.
  address          _stack_base;
  size_t           _stack_size;
  int              _lgrp_id;

public:
  // Stack overflow support
  address stack_base() const           { assert(_stack_base != NULL,"Sanity check"); return _stack_base; }
  void    set_stack_base(address base) { _stack_base = base; }
  size_t  stack_size() const           { return _stack_size; }
  void    set_stack_size(size_t size)  { _stack_size = size; }
  address stack_end()  const           { return stack_base() - stack_size(); }
  void    record_stack_base_and_size();
  void    register_thread_stack_with_NMT();
  void    unregister_thread_stack_with_NMT();

  int     lgrp_id() const        { return _lgrp_id; }
  void    set_lgrp_id(int value) { _lgrp_id = value; }

  // Printing
  void print_on(outputStream* st, bool print_extended_info) const;
  virtual void print_on(outputStream* st) const { print_on(st, false); }
  void print() const;
  virtual void print_on_error(outputStream* st, char* buf, int buflen) const;
  // Basic, non-virtual, printing support that is simple and always safe.
  void print_value_on(outputStream* st) const;

  // Debug-only code
#ifdef ASSERT
private:
  // Deadlock detection support for Mutex locks. List of locks own by thread.
  Mutex* _owned_locks;
  // Mutex::set_owner_implementation is the only place where _owned_locks is modified,
  // thus the friendship
  friend class Mutex;
  friend class Monitor;

public:
  void print_owned_locks_on(outputStream* st) const;
  void print_owned_locks() const                 { print_owned_locks_on(tty);    }
  Mutex* owned_locks() const                     { return _owned_locks;          }
  bool owns_locks() const                        { return owned_locks() != NULL; }

  // Deadlock detection
  ResourceMark* current_resource_mark()          { return _current_resource_mark; }
  void set_current_resource_mark(ResourceMark* rm) { _current_resource_mark = rm; }
#endif // ASSERT

private:
  volatile int _jvmti_env_iteration_count;

public:
  void entering_jvmti_env_iteration()            { ++_jvmti_env_iteration_count; }
  void leaving_jvmti_env_iteration()             { --_jvmti_env_iteration_count; }
  bool is_inside_jvmti_env_iteration()           { return _jvmti_env_iteration_count > 0; }

  // Code generation
  static ByteSize exception_file_offset()        { return byte_offset_of(Thread, _exception_file); }
  static ByteSize exception_line_offset()        { return byte_offset_of(Thread, _exception_line); }

  static ByteSize stack_base_offset()            { return byte_offset_of(Thread, _stack_base); }
  static ByteSize stack_size_offset()            { return byte_offset_of(Thread, _stack_size); }

  static ByteSize tlab_start_offset()            { return byte_offset_of(Thread, _tlab) + ThreadLocalAllocBuffer::start_offset(); }
  static ByteSize tlab_end_offset()              { return byte_offset_of(Thread, _tlab) + ThreadLocalAllocBuffer::end_offset(); }
  static ByteSize tlab_top_offset()              { return byte_offset_of(Thread, _tlab) + ThreadLocalAllocBuffer::top_offset(); }
  static ByteSize tlab_pf_top_offset()           { return byte_offset_of(Thread, _tlab) + ThreadLocalAllocBuffer::pf_top_offset(); }

  static ByteSize allocated_bytes_offset()       { return byte_offset_of(Thread, _allocated_bytes); }

  JFR_ONLY(DEFINE_THREAD_LOCAL_OFFSET_JFR;)

public:
  ParkEvent * volatile _ParkEvent;            // for Object monitors, JVMTI raw monitors,
                                              // and ObjectSynchronizer::read_stable_mark

  // Termination indicator used by the signal handler.
  // _ParkEvent is just a convenient field we can NULL out after setting the JavaThread termination state
  // (which can't itself be read from the signal handler if a signal hits during the Thread destructor).
  bool has_terminated()                       { return Atomic::load(&_ParkEvent) == NULL; };

  jint _hashStateW;                           // Marsaglia Shift-XOR thread-local RNG
  jint _hashStateX;                           // thread-specific hashCode generator state
  jint _hashStateY;
  jint _hashStateZ;

  // Low-level leaf-lock primitives used to implement synchronization.
  // Not for general synchronization use.
  static void SpinAcquire(volatile int * Lock, const char * Name);
  static void SpinRelease(volatile int * Lock);

#if defined(__APPLE__) && defined(AARCH64)
private:
  DEBUG_ONLY(bool _wx_init);
  WXMode _wx_state;
public:
  void init_wx();
  WXMode enable_wx(WXMode new_state);

  void assert_wx_state(WXMode expected) {
    assert(_wx_state == expected, "wrong state");
  }
#endif // __APPLE__ && AARCH64
};

// Inline implementation of Thread::current()
inline Thread* Thread::current() {
  Thread* current = current_or_null();
  assert(current != NULL, "Thread::current() called on detached thread");
  return current;
}

inline Thread* Thread::current_or_null() {
#ifndef USE_LIBRARY_BASED_TLS_ONLY
  return _thr_current;
#else
  if (ThreadLocalStorage::is_initialized()) {
    return ThreadLocalStorage::thread();
  }
  return NULL;
#endif
}

inline Thread* Thread::current_or_null_safe() {
  if (ThreadLocalStorage::is_initialized()) {
    return ThreadLocalStorage::thread();
  }
  return NULL;
}

#endif // SHARE_RUNTIME_THREAD_HPP

quality100%

¤ Dauer der Verarbeitung: 0.13 Sekunden (vorverarbeitet) ¤

Wurzel

Suchen

Beweissystem der NASA

Beweissystem Isabelle

NIST Cobol Testsuite

Cephes Mathematical Library

Wiener Entwicklungsmethode

Haftungshinweis

Die Informationen auf dieser Webseite wurden nach bestem Wissen sorgfältig zusammengestellt. Es wird jedoch weder Vollständigkeit, noch Richtigkeit, noch Qualität der bereit gestellten Informationen zugesichert.