| /* Machine-specific definition for spin locks. PowerPC version. |
| Copyright (C) 1994,97,2002,2007 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) |
| { |
| long int __locked; |
| __asm__ __volatile__ ("\ |
| 0: lwarx %0,0,%1\n\ |
| stwcx. %2,0,%1\n\ |
| bne- 0b\n\ |
| " : "=&r" (__locked) : "r" (__lock), "r" (0) : "cr0"); |
| } |
| |
| /* 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) |
| { |
| long int __rtn; |
| __asm__ __volatile__ ("\ |
| 0: lwarx %0,0,%1\n\ |
| stwcx. %2,0,%1\n\ |
| bne- 0b\n\ |
| " : "=&r" (__rtn) : "r" (__lock), "r" (1) : "cr0"); |
| return !__rtn; |
| } |
| |
| /* Return nonzero if LOCK is locked. */ |
| |
| _EXTERN_INLINE int |
| __spin_lock_locked (__spin_lock_t *__lock) |
| { |
| long int __rtn; |
| __asm__ __volatile__ ("\ |
| 0: lwarx %0,0,%1\n\ |
| stwcx. %0,0,%1\n\ |
| bne- 0b\n\ |
| " : "=&r" (__rtn) : "r" (__lock) : "cr0"); |
| return __rtn; |
| } |
| |
| |
| #endif /* machine-lock.h */ |