+++ /dev/null
-/*
- *
- *
- * Copyright (c) 1994
- * Hewlett-Packard Company
- *
- * Copyright (c) 1996,1997
- * Silicon Graphics Computer Systems, Inc.
- *
- * Copyright (c) 1997
- * Moscow Center for SPARC Technology
- *
- * Copyright (c) 1999
- * Boris Fomitchev
- *
- * This material is provided "as is", with absolutely no warranty expressed
- * or implied. Any use is at your own risk.
- *
- * Permission to use or copy this software for any purpose is hereby granted
- * without fee, provided the above notices are retained on all copies.
- * Permission to modify the code and to distribute modified code is granted,
- * provided the above notices are retained, and a notice that the code was
- * modified is included with the above copyright notice.
- *
- */
-#ifndef _STLP_THREADS_C
-#define _STLP_THREADS_C
-
-#ifndef _STLP_INTERNAL_THREADS_H
-# include <stl/_threads.h>
-#endif
-
-#if defined (_STLP_EXPOSE_GLOBALS_IMPLEMENTATION)
-
-#if defined (_STLP_SGI_THREADS)
-# include <time.h>
-#elif defined (_STLP_UNIX)
-# ifndef _STLP_INTERNAL_CTIME
-# include <stl/_ctime.h>
-# endif
-# if defined (_STLP_USE_NAMESPACES) && !defined (_STLP_VENDOR_GLOBAL_CSTD)
-using _STLP_VENDOR_CSTD::time_t;
-# endif
-# include <sys/time.h>
-#endif
-
-_STLP_BEGIN_NAMESPACE
-
-#if defined (_STLP_USE_ATOMIC_SWAP_MUTEX)
-template<int __32bits>
-_STLP_STATIC_MUTEX
-_Atomic_swap_struct<__32bits>::_S_swap_lock _STLP_MUTEX_INITIALIZER;
-# undef _STLP_USE_ATOMIC_SWAP_MUTEX
-#endif
-
-#if defined (_STLP_THREADS) && !defined (_STLP_USE_PTHREAD_SPINLOCK)
-template <int __inst>
-unsigned _STLP_mutex_spin<__inst>::__max = _STLP_mutex_spin<__inst>::__low_max;
-
-template <int __inst>
-unsigned _STLP_mutex_spin<__inst>::__last = 0;
-#endif // _STLP_USE_PTHREAD_SPINLOCK
-
-#if defined (_STLP_THREADS) && !defined (_STLP_USE_PTHREAD_SPINLOCK)
-
-# if defined (_STLP_SPARC_SOLARIS_THREADS)
-// underground function in libc.so; we do not want dependance on librt
-extern "C" int __nanosleep(const struct timespec*, struct timespec*);
-# define _STLP_NANOSLEEP __nanosleep
-# else
-# define _STLP_NANOSLEEP nanosleep
-# endif
-
-template <int __inst>
-void _STLP_CALL
-_STLP_mutex_spin<__inst>::_S_nsec_sleep(int __log_nsec, unsigned int& __iteration) {
-# if defined (_STLP_WIN32THREADS)
-# if defined (_WIN32_WINNT) && (_WIN32_WINNT >= 0x0400)
- if (__iteration <= 4000) {
- // Use SwitchToThread because
- // 1) Sleep(1) often takes ~15 ms
- // 2) SwitchToThread yields to lower-priority threads
- // 4000 is enough to avoid Sleep and is used just to prevent infinite looping
- // This number is advised spin count for Heap management by Microsoft
- SwitchToThread();
- } else {
-# endif
- if (__log_nsec <= 21) {
- /* Note from boost (www.boost.org):
- * Changed from Sleep(0) to Sleep(1).
- * According to MSDN, Sleep(0) will never yield to a lower-priority thread,
- * whereas Sleep(1) will. Performance seems not to be affected. */
- Sleep(1);
- } else {
- Sleep(1 << (__log_nsec - 20));
- }
-# if defined (_WIN32_WINNT) && (_WIN32_WINNT >= 0x0400)
- __iteration = 0; //reset to avoid sleeps sequence
- }
-# endif
-# elif defined(_STLP_OS2THREADS)
- if (__log_nsec <= 20) {
- DosSleep(0);
- } else {
- DosSleep(1 << (__log_nsec - 20));
- }
-# elif defined (_STLP_UNIX)
- timespec __ts;
- /* Max sleep is 2**27nsec ~ 60msec */
- __ts.tv_sec = 0;
- __ts.tv_nsec = 1 << __log_nsec;
- _STLP_NANOSLEEP(&__ts, 0);
-# endif
-}
-
-template <int __inst>
-void _STLP_CALL
-_STLP_mutex_spin<__inst>::_M_do_lock(volatile __stl_atomic_t* __lock) {
-# if defined(_STLP_ATOMIC_EXCHANGE)
- if (_Atomic_swap(__lock, 1)) {
- unsigned __my_spin_max = _STLP_mutex_spin<0>::__max;
- unsigned __my_last_spins = _STLP_mutex_spin<0>::__last;
- volatile unsigned __junk = 17; // Value doesn't matter.
- unsigned __i;
-
- for (__i = 0; __i < __my_spin_max; ++__i) {
- if (__i < __my_last_spins/2 || *__lock) {
- __junk *= __junk; __junk *= __junk;
- __junk *= __junk; __junk *= __junk;
- } else {
- if (!_Atomic_swap(__lock, 1)) {
- // got it!
- // Spinning worked. Thus we're probably not being scheduled
- // against the other process with which we were contending.
- // Thus it makes sense to spin longer the next time.
- _STLP_mutex_spin<0>::__last = __i;
- _STLP_mutex_spin<0>::__max = _STLP_mutex_spin<0>::__high_max;
- return;
- }
- }
- }
-
- // We are probably being scheduled against the other process. Sleep.
- _STLP_mutex_spin<0>::__max = _STLP_mutex_spin<0>::__low_max;
-
- for (__i = 0 ;; ++__i) {
- int __log_nsec = __i + 6;
-
- if (__log_nsec > 27) __log_nsec = 27;
- if (!_Atomic_swap(__lock, 1)) {
- break;
- }
- _S_nsec_sleep(__log_nsec, __i);
- }
- } /* first _Atomic_swap */
-# endif
-}
-#endif // _STLP_USE_PTHREAD_SPINLOCK
-
-_STLP_END_NAMESPACE
-
-#endif /* _STLP_EXPOSE_GLOBALS_IMPLEMENTATION */
-#endif /* _STLP_THREADS_C */
-
-// Local Variables:
-// mode:C++
-// End:
projects / reactos.git / blobdiff