/* Machine-specific definition for spin locks.  Alpha version.   Copyright (C) 1994, 1997 Free Software Foundation, Inc.   This file is part of the GNU C Library.   The GNU C Library is free software; you can redistribute it and/or   modify it under the terms of the GNU Lesser General Public   License as published by the Free Software Foundation; either   version 2.1 of the License, or (at your option) any later version.   The GNU C Library 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   Lesser General Public License for more details.   You should have received a copy of the GNU Lesser General Public   License along with the GNU C Library; if not, write to the Free   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA   02111-1307 USA.  */#ifndef _MACHINE_LOCK_H#define	_MACHINE_LOCK_H/* The type of a spin lock variable.  */typedef __volatile long int __spin_lock_t;/* Value to initialize `__spin_lock_t' variables to.  */#define	__SPIN_LOCK_INITIALIZER	0L#ifndef _EXTERN_INLINE#define _EXTERN_INLINE extern __inline#endif/* Unlock LOCK.  */_EXTERN_INLINE void__spin_unlock (__spin_lock_t *__lock){  __asm__ __volatile__ ("mb; stq $31, %0; mb"			: "=m" (__lock));}/* Try to lock LOCK; return nonzero if we locked it, zero if another has.  */_EXTERN_INLINE int__spin_try_lock (register __spin_lock_t *__lock){  register long int __rtn, __tmp;  do    {      __asm__ __volatile__ ("mb; ldq_l %0,%1" /* Load lock value into TMP.  */			    : "=r" (__tmp) : "m" (*__lock));      __rtn = 2;		/* Load locked value into RTN.  */      if (__tmp)	/* The lock is already taken.  */	return 0;      /* The lock is not taken; try to get it now.  */      __asm__ __volatile__ ("stq_c %0,%1"			    : "=r" (__rtn), "=m" (*__lock)			    : "0" (__rtn), "1" (*__lock));      /* RTN is clear if stq_c was interrupted; loop to try the lock again.  */   } while (! __rtn);  /* RTN is now nonzero; we have the lock.  */  return __rtn;}/* Return nonzero if LOCK is locked.  */_EXTERN_INLINE int__spin_lock_locked (__spin_lock_t *__lock){  return *__lock != 0;}#endif /* machine-lock.h */