| xf.li | bdd93d5 | 2023-05-12 07:10:14 -0700 | [diff] [blame] | 1 | /* Machine-specific definition for spin locks. Stub version. |
| 2 | Copyright (C) 1994-2016 Free Software Foundation, Inc. |
| 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 |
| 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. |
| 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 |
| 13 | Lesser General Public License for more details. |
| 14 | |
| 15 | You should have received a copy of the GNU Lesser General Public |
| 16 | License along with the GNU C Library; if not, see |
| 17 | <http://www.gnu.org/licenses/>. */ |
| 18 | |
| 19 | #ifndef _MACHINE_LOCK_H |
| 20 | #define _MACHINE_LOCK_H |
| 21 | |
| 22 | /* The type of a spin lock variable. */ |
| 23 | |
| 24 | typedef volatile int __spin_lock_t; |
| 25 | |
| 26 | /* Value to initialize `__spin_lock_t' variables to. */ |
| 27 | |
| 28 | #define __SPIN_LOCK_INITIALIZER 0 |
| 29 | |
| 30 | |
| 31 | #ifndef _EXTERN_INLINE |
| 32 | #define _EXTERN_INLINE __extern_inline |
| 33 | #endif |
| 34 | |
| 35 | /* Unlock LOCK. */ |
| 36 | |
| 37 | _EXTERN_INLINE void |
| 38 | __spin_unlock (__spin_lock_t *__lock) |
| 39 | { |
| 40 | *__lock = 0; |
| 41 | } |
| 42 | |
| 43 | /* Try to lock LOCK; return nonzero if we locked it, zero if another has. */ |
| 44 | |
| 45 | _EXTERN_INLINE int |
| 46 | __spin_try_lock (__spin_lock_t *__lock) |
| 47 | { |
| 48 | if (*__lock) |
| 49 | return 0; |
| 50 | *__lock = 1; |
| 51 | return 1; |
| 52 | } |
| 53 | |
| 54 | /* Return nonzero if LOCK is locked. */ |
| 55 | |
| 56 | _EXTERN_INLINE int |
| 57 | __spin_lock_locked (__spin_lock_t *__lock) |
| 58 | { |
| 59 | return *__lock != 0; |
| 60 | } |
| 61 | |
| 62 | |
| 63 | #endif /* machine-lock.h */ |