diff options
Diffstat (limited to 'sysdeps/mach/mips/machine-lock.h')
-rw-r--r-- | sysdeps/mach/mips/machine-lock.h | 73 |
1 files changed, 73 insertions, 0 deletions
diff --git a/sysdeps/mach/mips/machine-lock.h b/sysdeps/mach/mips/machine-lock.h new file mode 100644 index 0000000..628aae4 --- /dev/null +++ b/sysdeps/mach/mips/machine-lock.h @@ -0,0 +1,73 @@ +/* Machine-specific definition for spin locks. MIPS version. +Copyright (C) 1994 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 Library General Public License as +published by the Free Software Foundation; either version 2 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 +Library General Public License for more details. + +You should have received a copy of the GNU Library General Public +License along with the GNU C Library; see the file COPYING.LIB. If +not, write to the Free Software Foundation, Inc., 675 Mass Ave, +Cambridge, MA 02139, USA. */ + +#ifndef _MACHINE_LOCK_H +#define _MACHINE_LOCK_H + +/* The type of a spin lock variable. */ + +typedef __volatile int __spin_lock_t; + +/* Value to initialize `__spin_lock_t' variables to. */ + +#define __SPIN_LOCK_INITIALIZER 0 + + +#ifndef _EXTERN_INLINE +#define _EXTERN_INLINE extern __inline +#endif + +/* Unlock LOCK. */ + +_EXTERN_INLINE void +__spin_unlock (__spin_lock_t *__lock) +{ + *__lock = 0; +} + +/* 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 int __rtn; + __asm__ __volatile (".set noreorder"); +#if 0 + __asm__ __volatile ("lw %0,0(%1)": "=r" (__rtn) : "r" (__lock)); + __asm__ __volatile ("sw %0,0(%0)": : "r" (__lock)); + __asm__ __volatile ("xor %0,%1,%0": "=r" (__rtn) : "r" (__lock)); +#else + /* Use the Mach microkernel's emulated TAS pseudo-instruction. */ + register int __rtn __asm__ ("a0"); + __asm__ __volatile (".word 0xf ! %0 " : "=r" (__rtn) : "0" (__lock)); +#endif + __asm__ __volatile (".set reorder"); + return __rtn ^ (int) __lock; +} + +/* Return nonzero if LOCK is locked. */ + +_EXTERN_INLINE int +__spin_lock_locked (__spin_lock_t *__lock) +{ + return *__lock != 0; +} + + +#endif /* machine-lock.h */ |