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Diffstat (limited to 'arch/x86/include/asm/atomic64_32.h')
| -rw-r--r-- | arch/x86/include/asm/atomic64_32.h | 304 |
1 files changed, 304 insertions, 0 deletions
diff --git a/arch/x86/include/asm/atomic64_32.h b/arch/x86/include/asm/atomic64_32.h new file mode 100644 index 000000000000..2a934aa19a43 --- /dev/null +++ b/arch/x86/include/asm/atomic64_32.h @@ -0,0 +1,304 @@ +#ifndef _ASM_X86_ATOMIC64_32_H +#define _ASM_X86_ATOMIC64_32_H + +#include <linux/compiler.h> +#include <linux/types.h> +#include <asm/processor.h> +//#include <asm/cmpxchg.h> + +/* An 64bit atomic type */ + +typedef struct { + u64 __aligned(8) counter; +} atomic64_t; + +#define ATOMIC64_INIT(val) { (val) } + +#ifdef CONFIG_X86_CMPXCHG64 +#define ATOMIC64_ALTERNATIVE_(f, g) "call atomic64_" #g "_cx8" +#else +#define ATOMIC64_ALTERNATIVE_(f, g) ALTERNATIVE("call atomic64_" #f "_386", "call atomic64_" #g "_cx8", X86_FEATURE_CX8) +#endif + +#define ATOMIC64_ALTERNATIVE(f) ATOMIC64_ALTERNATIVE_(f, f) + +/** + * atomic64_cmpxchg - cmpxchg atomic64 variable + * @p: pointer to type atomic64_t + * @o: expected value + * @n: new value + * + * Atomically sets @v to @n if it was equal to @o and returns + * the old value. + */ + +static inline long long atomic64_cmpxchg(atomic64_t *v, long long o, long long n) +{ + return cmpxchg64(&v->counter, o, n); +} + +/** + * atomic64_xchg - xchg atomic64 variable + * @v: pointer to type atomic64_t + * @n: value to assign + * + * Atomically xchgs the value of @v to @n and returns + * the old value. + */ +static inline long long atomic64_xchg(atomic64_t *v, long long n) +{ + long long o; + unsigned high = (unsigned)(n >> 32); + unsigned low = (unsigned)n; + asm volatile(ATOMIC64_ALTERNATIVE(xchg) + : "=A" (o), "+b" (low), "+c" (high) + : "S" (v) + : "memory" + ); + return o; +} + +/** + * atomic64_set - set atomic64 variable + * @v: pointer to type atomic64_t + * @n: value to assign + * + * Atomically sets the value of @v to @n. + */ +static inline void atomic64_set(atomic64_t *v, long long i) +{ + unsigned high = (unsigned)(i >> 32); + unsigned low = (unsigned)i; + asm volatile(ATOMIC64_ALTERNATIVE(set) + : "+b" (low), "+c" (high) + : "S" (v) + : "eax", "edx", "memory" + ); +} + +/** + * atomic64_read - read atomic64 variable + * @v: pointer to type atomic64_t + * + * Atomically reads the value of @v and returns it. + */ +static inline long long atomic64_read(atomic64_t *v) +{ + long long r; + asm volatile(ATOMIC64_ALTERNATIVE(read) + : "=A" (r), "+c" (v) + : : "memory" + ); + return r; + } + +/** + * atomic64_add_return - add and return + * @i: integer value to add + * @v: pointer to type atomic64_t + * + * Atomically adds @i to @v and returns @i + *@v + */ +static inline long long atomic64_add_return(long long i, atomic64_t *v) +{ + asm volatile(ATOMIC64_ALTERNATIVE(add_return) + : "+A" (i), "+c" (v) + : : "memory" + ); + return i; +} + +/* + * Other variants with different arithmetic operators: + */ +static inline long long atomic64_sub_return(long long i, atomic64_t *v) +{ + asm volatile(ATOMIC64_ALTERNATIVE(sub_return) + : "+A" (i), "+c" (v) + : : "memory" + ); + return i; +} + +static inline long long atomic64_inc_return(atomic64_t *v) +{ + long long a; + asm volatile(ATOMIC64_ALTERNATIVE(inc_return) + : "=A" (a) + : "S" (v) + : "memory", "ecx" + ); + return a; +} + +static inline long long atomic64_dec_return(atomic64_t *v) +{ + long long a; + asm volatile(ATOMIC64_ALTERNATIVE(dec_return) + : "=A" (a) + : "S" (v) + : "memory", "ecx" + ); + return a; +} + +/** + * atomic64_add - add integer to atomic64 variable + * @i: integer value to add + * @v: pointer to type atomic64_t + * + * Atomically adds @i to @v. + */ +static inline long long atomic64_add(long long i, atomic64_t *v) +{ + asm volatile(ATOMIC64_ALTERNATIVE_(add, add_return) + : "+A" (i), "+c" (v) + : : "memory" + ); + return i; +} + +/** + * atomic64_sub - subtract the atomic64 variable + * @i: integer value to subtract + * @v: pointer to type atomic64_t + * + * Atomically subtracts @i from @v. + */ +static inline long long atomic64_sub(long long i, atomic64_t *v) +{ + asm volatile(ATOMIC64_ALTERNATIVE_(sub, sub_return) + : "+A" (i), "+c" (v) + : : "memory" + ); + return i; +} + +/** + * atomic64_sub_and_test - subtract value from variable and test result + * @i: integer value to subtract + * @v: pointer to type atomic64_t + * + * Atomically subtracts @i from @v and returns + * true if the result is zero, or false for all + * other cases. + */ +static inline int atomic64_sub_and_test(long long i, atomic64_t *v) +{ + return atomic64_sub_return(i, v) == 0; +} + +/** + * atomic64_inc - increment atomic64 variable + * @v: pointer to type atomic64_t + * + * Atomically increments @v by 1. + */ +static inline void atomic64_inc(atomic64_t *v) +{ + asm volatile(ATOMIC64_ALTERNATIVE_(inc, inc_return) + : : "S" (v) + : "memory", "eax", "ecx", "edx" + ); +} + +/** + * atomic64_dec - decrement atomic64 variable + * @ptr: pointer to type atomic64_t + * + * Atomically decrements @ptr by 1. + */ +static inline void atomic64_dec(atomic64_t *v) +{ + asm volatile(ATOMIC64_ALTERNATIVE_(dec, dec_return) + : : "S" (v) + : "memory", "eax", "ecx", "edx" + ); +} + +/** + * atomic64_dec_and_test - decrement and test + * @v: pointer to type atomic64_t + * + * Atomically decrements @v by 1 and + * returns true if the result is 0, or false for all other + * cases. + */ +static inline int atomic64_dec_and_test(atomic64_t *v) +{ + return atomic64_dec_return(v) == 0; +} + +/** + * atomic64_inc_and_test - increment and test + * @v: pointer to type atomic64_t + * + * Atomically increments @v by 1 + * and returns true if the result is zero, or false for all + * other cases. + */ +static inline int atomic64_inc_and_test(atomic64_t *v) +{ + return atomic64_inc_return(v) == 0; +} + +/** + * atomic64_add_negative - add and test if negative + * @i: integer value to add + * @v: pointer to type atomic64_t + * + * Atomically adds @i to @v and returns true + * if the result is negative, or false when + * result is greater than or equal to zero. + */ +static inline int atomic64_add_negative(long long i, atomic64_t *v) +{ + return atomic64_add_return(i, v) < 0; +} + +/** + * atomic64_add_unless - add unless the number is a given value + * @v: pointer of type atomic64_t + * @a: the amount to add to v... + * @u: ...unless v is equal to u. + * + * Atomically adds @a to @v, so long as it was not @u. + * Returns non-zero if @v was not @u, and zero otherwise. + */ +static inline int atomic64_add_unless(atomic64_t *v, long long a, long long u) +{ + unsigned low = (unsigned)u; + unsigned high = (unsigned)(u >> 32); + asm volatile(ATOMIC64_ALTERNATIVE(add_unless) "\n\t" + : "+A" (a), "+c" (v), "+S" (low), "+D" (high) + : : "memory"); + return (int)a; +} + + +static inline int atomic64_inc_not_zero(atomic64_t *v) +{ + int r; + asm volatile(ATOMIC64_ALTERNATIVE(inc_not_zero) + : "=a" (r) + : "S" (v) + : "ecx", "edx", "memory" + ); + return r; +} + +static inline long long atomic64_dec_if_positive(atomic64_t *v) +{ + long long r; + asm volatile(ATOMIC64_ALTERNATIVE(dec_if_positive) + : "=A" (r) + : "S" (v) + : "ecx", "memory" + ); + return r; +} + +#undef ATOMIC64_ALTERNATIVE +#undef ATOMIC64_ALTERNATIVE_ + +#endif /* _ASM_X86_ATOMIC64_32_H */ |