projects / thirdparty / glibc.git / blame
| Commit | Line | Data |
|---|---|---|
| 28f540f4 | 1 | /* Machine-specific definition for spin locks. i386 version. |
| 568035b7 | 2 | Copyright (C) 1994-2013 Free Software Foundation, Inc. |
| 478b92f0 UD |
3 | This file is part of the GNU C Library. |
| 4 | ||
| 5 | The GNU C Library is free software; you can redistribute it and/or | |
| 41bdb6e2 AJ |
6 | modify it under the terms of the GNU Lesser General Public |
| 7 | License as published by the Free Software Foundation; either | |
| 8 | version 2.1 of the License, or (at your option) any later version. | |
| 478b92f0 UD |
9 | |
| 10 | The GNU C Library is distributed in the hope that it will be useful, | |
| 11 | but WITHOUT ANY WARRANTY; without even the implied warranty of | |
| 12 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
| 41bdb6e2 | 13 | Lesser General Public License for more details. |
| 478b92f0 | 14 | |
| 41bdb6e2 | 15 | You should have received a copy of the GNU Lesser General Public |
| 59ba27a6 PE |
16 | License along with the GNU C Library; if not, see |
| 17 | <http://www.gnu.org/licenses/>. */ | |
| 28f540f4 RM |
18 | |
| 19 | #ifndef _MACHINE_LOCK_H | |
| 20 | #define _MACHINE_LOCK_H | |
| 21 | ||
| 22 | /* The type of a spin lock variable. */ | |
| 23 | ||
| c3b1bf7d | 24 | typedef volatile int __spin_lock_t; |
| 28f540f4 RM |
25 | |
| 26 | /* Value to initialize `__spin_lock_t' variables to. */ | |
| 27 | ||
| 28 | #define __SPIN_LOCK_INITIALIZER 0 | |
| 29 | ||
| 30 | ||
| 31 | #ifndef _EXTERN_INLINE | |
| b037a293 | 32 | #define _EXTERN_INLINE __extern_inline |
| 28f540f4 RM |
33 | #endif |
| 34 | ||
| 35 | /* Unlock LOCK. */ | |
| 36 | ||
| 37 | _EXTERN_INLINE void | |
| 38 | __spin_unlock (__spin_lock_t *__lock) | |
| 39 | { | |
| 40 | register int __unlocked; | |
| 41 | __asm__ __volatile ("xchgl %0, %1" | |
| 4c8ac845 | 42 | : "=&r" (__unlocked), "=m" (*__lock) : "0" (0) |
| b5ec4f43 | 43 | : "memory"); |
| 28f540f4 RM |
44 | } |
| 45 | ||
| 46 | /* Try to lock LOCK; return nonzero if we locked it, zero if another has. */ | |
| 47 | ||
| 48 | _EXTERN_INLINE int | |
| 49 | __spin_try_lock (__spin_lock_t *__lock) | |
| 50 | { | |
| 51 | register int __locked; | |
| 52 | __asm__ __volatile ("xchgl %0, %1" | |
| 4c8ac845 | 53 | : "=&r" (__locked), "=m" (*__lock) : "0" (1) |
| b5ec4f43 | 54 | : "memory"); |
| 28f540f4 RM |
55 | return !__locked; |
| 56 | } | |
| 57 | ||
| 58 | /* Return nonzero if LOCK is locked. */ | |
| 59 | ||
| 60 | _EXTERN_INLINE int | |
| 61 | __spin_lock_locked (__spin_lock_t *__lock) | |
| 62 | { | |
| 63 | return *__lock != 0; | |
| 64 | } | |
| 65 | ||
| 66 | ||
| 67 | #endif /* machine-lock.h */ |