| Paul Mackerras | 09d4e0e | 2009-06-12 21:10:05 +0000 | [diff] [blame] | 1 | /* |
| 2 | * Generic implementation of 64-bit atomics using spinlocks, |
| 3 | * useful on processors that don't have 64-bit atomic instructions. |
| 4 | * |
| 5 | * Copyright © 2009 Paul Mackerras, IBM Corp. <paulus@au1.ibm.com> |
| 6 | * |
| 7 | * This program is free software; you can redistribute it and/or |
| 8 | * modify it under the terms of the GNU General Public License |
| 9 | * as published by the Free Software Foundation; either version |
| 10 | * 2 of the License, or (at your option) any later version. |
| 11 | */ |
| 12 | #ifndef _ASM_GENERIC_ATOMIC64_H |
| 13 | #define _ASM_GENERIC_ATOMIC64_H |
| 14 | |
| 15 | typedef struct { |
| 16 | long long counter; |
| 17 | } atomic64_t; |
| 18 | |
| 19 | #define ATOMIC64_INIT(i) { (i) } |
| 20 | |
| 21 | extern long long atomic64_read(const atomic64_t *v); |
| 22 | extern void atomic64_set(atomic64_t *v, long long i); |
| 23 | extern void atomic64_add(long long a, atomic64_t *v); |
| 24 | extern long long atomic64_add_return(long long a, atomic64_t *v); |
| 25 | extern void atomic64_sub(long long a, atomic64_t *v); |
| 26 | extern long long atomic64_sub_return(long long a, atomic64_t *v); |
| 27 | extern long long atomic64_dec_if_positive(atomic64_t *v); |
| 28 | extern long long atomic64_cmpxchg(atomic64_t *v, long long o, long long n); |
| 29 | extern long long atomic64_xchg(atomic64_t *v, long long new); |
| 30 | extern int atomic64_add_unless(atomic64_t *v, long long a, long long u); |
| 31 | |
| 32 | #define atomic64_add_negative(a, v) (atomic64_add_return((a), (v)) < 0) |
| 33 | #define atomic64_inc(v) atomic64_add(1LL, (v)) |
| 34 | #define atomic64_inc_return(v) atomic64_add_return(1LL, (v)) |
| 35 | #define atomic64_inc_and_test(v) (atomic64_inc_return(v) == 0) |
| 36 | #define atomic64_sub_and_test(a, v) (atomic64_sub_return((a), (v)) == 0) |
| 37 | #define atomic64_dec(v) atomic64_sub(1LL, (v)) |
| 38 | #define atomic64_dec_return(v) atomic64_sub_return(1LL, (v)) |
| 39 | #define atomic64_dec_and_test(v) (atomic64_dec_return((v)) == 0) |
| 40 | #define atomic64_inc_not_zero(v) atomic64_add_unless((v), 1LL, 0LL) |
| 41 | |
| 42 | #endif /* _ASM_GENERIC_ATOMIC64_H */ |