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Diffstat (limited to 'include/asm-generic/atomic64.h')
| -rw-r--r-- | include/asm-generic/atomic64.h | 54 |
1 files changed, 54 insertions, 0 deletions
diff --git a/include/asm-generic/atomic64.h b/include/asm-generic/atomic64.h new file mode 100644 index 000000000..30ad9c86c --- /dev/null +++ b/include/asm-generic/atomic64.h @@ -0,0 +1,54 @@ +/* + * Generic implementation of 64-bit atomics using spinlocks, + * useful on processors that don't have 64-bit atomic instructions. + * + * Copyright © 2009 Paul Mackerras, IBM Corp. <paulus@au1.ibm.com> + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version + * 2 of the License, or (at your option) any later version. + */ +#ifndef _ASM_GENERIC_ATOMIC64_H +#define _ASM_GENERIC_ATOMIC64_H + +typedef struct { + long long counter; +} atomic64_t; + +#define ATOMIC64_INIT(i) { (i) } + +extern long long atomic64_read(const atomic64_t *v); +extern void atomic64_set(atomic64_t *v, long long i); + +#define ATOMIC64_OP(op) \ +extern void atomic64_##op(long long a, atomic64_t *v); + +#define ATOMIC64_OP_RETURN(op) \ +extern long long atomic64_##op##_return(long long a, atomic64_t *v); + +#define ATOMIC64_OPS(op) ATOMIC64_OP(op) ATOMIC64_OP_RETURN(op) + +ATOMIC64_OPS(add) +ATOMIC64_OPS(sub) + +#undef ATOMIC64_OPS +#undef ATOMIC64_OP_RETURN +#undef ATOMIC64_OP + +extern long long atomic64_dec_if_positive(atomic64_t *v); +extern long long atomic64_cmpxchg(atomic64_t *v, long long o, long long n); +extern long long atomic64_xchg(atomic64_t *v, long long new); +extern int atomic64_add_unless(atomic64_t *v, long long a, long long u); + +#define atomic64_add_negative(a, v) (atomic64_add_return((a), (v)) < 0) +#define atomic64_inc(v) atomic64_add(1LL, (v)) +#define atomic64_inc_return(v) atomic64_add_return(1LL, (v)) +#define atomic64_inc_and_test(v) (atomic64_inc_return(v) == 0) +#define atomic64_sub_and_test(a, v) (atomic64_sub_return((a), (v)) == 0) +#define atomic64_dec(v) atomic64_sub(1LL, (v)) +#define atomic64_dec_return(v) atomic64_sub_return(1LL, (v)) +#define atomic64_dec_and_test(v) (atomic64_dec_return((v)) == 0) +#define atomic64_inc_not_zero(v) atomic64_add_unless((v), 1LL, 0LL) + +#endif /* _ASM_GENERIC_ATOMIC64_H */ |