#ifndef _ASM_X86_ATOMIC64_32_H #define _ASM_X86_ATOMIC64_32_H #include #include #include #include /* An 64bit atomic type */ typedef struct { u64 __aligned(8) counter; } atomic64_t; #define ATOMIC64_INIT(val) { (val) } #define __ATOMIC64_DECL(sym) void atomic64_##sym(atomic64_t *, ...) #ifndef ATOMIC64_EXPORT #define ATOMIC64_DECL_ONE __ATOMIC64_DECL #else #define ATOMIC64_DECL_ONE(sym) __ATOMIC64_DECL(sym); \ ATOMIC64_EXPORT(atomic64_##sym) #endif #ifdef CONFIG_X86_CMPXCHG64 #define __alternative_atomic64(f, g, out, in...) \ asm volatile("call %P[func]" \ : out : [func] "i" (atomic64_##g##_cx8), ## in) #define ATOMIC64_DECL(sym) ATOMIC64_DECL_ONE(sym##_cx8) #else #define __alternative_atomic64(f, g, out, in...) \ alternative_call(atomic64_##f##_386, atomic64_##g##_cx8, \ X86_FEATURE_CX8, ASM_OUTPUT2(out), ## in) #define ATOMIC64_DECL(sym) ATOMIC64_DECL_ONE(sym##_cx8); \ ATOMIC64_DECL_ONE(sym##_386) ATOMIC64_DECL_ONE(add_386); ATOMIC64_DECL_ONE(sub_386); ATOMIC64_DECL_ONE(inc_386); ATOMIC64_DECL_ONE(dec_386); #endif #define alternative_atomic64(f, out, in...) \ __alternative_atomic64(f, f, ASM_OUTPUT2(out), ## in) ATOMIC64_DECL(read); ATOMIC64_DECL(set); ATOMIC64_DECL(xchg); ATOMIC64_DECL(add_return); ATOMIC64_DECL(sub_return); ATOMIC64_DECL(inc_return); ATOMIC64_DECL(dec_return); ATOMIC64_DECL(dec_if_positive); ATOMIC64_DECL(inc_not_zero); ATOMIC64_DECL(add_unless); #undef ATOMIC64_DECL #undef ATOMIC64_DECL_ONE #undef __ATOMIC64_DECL #undef ATOMIC64_EXPORT /** * atomic64_cmpxchg - cmpxchg atomic64 variable * @v: 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( "1: \n\t" "cmpxchg8b (%%esi) \n\t" "jnz 1b \n\t" :"=&A" (o) :"S" (v), "b" (low), "c" (high) : "memory", "cc"); return o; } /** * atomic64_set - set atomic64 variable * @v: pointer to type atomic64_t * @i: value to assign * * Atomically sets the value of @v to @n. */ static inline void atomic64_set(atomic64_t *v, long long i) { __sync_lock_test_and_set((long long *)&v->counter, i); } /** * 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(const atomic64_t *v) { return __sync_fetch_and_add( (long long *)&v->counter, 0); } /** * 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) { alternative_atomic64(add_return, ASM_OUTPUT2("+A" (i), "+c" (v)), ASM_NO_INPUT_CLOBBER("memory")); return i; } /* * Other variants with different arithmetic operators: */ static inline long long atomic64_sub_return(long long i, atomic64_t *v) { alternative_atomic64(sub_return, ASM_OUTPUT2("+A" (i), "+c" (v)), ASM_NO_INPUT_CLOBBER("memory")); return i; } static inline long long atomic64_inc_return(atomic64_t *v) { long long a; alternative_atomic64(inc_return, "=&A" (a), "S" (v) : "memory", "ecx"); return a; } static inline long long atomic64_dec_return(atomic64_t *v) { long long a; alternative_atomic64(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) { __alternative_atomic64(add, add_return, ASM_OUTPUT2("+A" (i), "+c" (v)), ASM_NO_INPUT_CLOBBER("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) { __alternative_atomic64(sub, sub_return, ASM_OUTPUT2("+A" (i), "+c" (v)), ASM_NO_INPUT_CLOBBER("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) { __alternative_atomic64(inc, inc_return, /* no output */, "S" (v) : "memory", "eax", "ecx", "edx"); } /** * atomic64_dec - decrement atomic64 variable * @v: pointer to type atomic64_t * * Atomically decrements @v by 1. */ static inline void atomic64_dec(atomic64_t *v) { __alternative_atomic64(dec, dec_return, /* no output */, "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 the add was done, 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); alternative_atomic64(add_unless, ASM_OUTPUT2("+A" (a), "+c" (low), "+D" (high)), "S" (v) : "memory"); return (int)a; } static inline int atomic64_inc_not_zero(atomic64_t *v) { int r; alternative_atomic64(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; alternative_atomic64(dec_if_positive, "=&A" (r), "S" (v) : "ecx", "memory"); return r; } #undef alternative_atomic64 #undef __alternative_atomic64 #define ATOMIC64_OP(op, c_op) \ static inline void atomic64_##op(long long i, atomic64_t *v) \ { \ long long old, c = 0; \ while ((old = atomic64_cmpxchg(v, c, c c_op i)) != c) \ c = old; \ } ATOMIC64_OP(and, &) ATOMIC64_OP(or, |) ATOMIC64_OP(xor, ^) #undef ATOMIC64_OP #endif /* _ASM_X86_ATOMIC64_32_H */