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- #ifndef _ASM_X86_ATOMIC64_64_H
- #define _ASM_X86_ATOMIC64_64_H
- #include <linux/types.h>
- #include <asm/alternative.h>
- #include <asm/cmpxchg.h>
- /* The 64-bit atomic type */
- #define ATOMIC64_INIT(i) { (i) }
- /**
- * atomic64_read - read atomic64 variable
- * @v: pointer of type atomic64_t
- *
- * Atomically reads the value of @v.
- * Doesn't imply a read memory barrier.
- */
- static inline long atomic64_read(const atomic64_t *v)
- {
- return (*(volatile long *)&(v)->counter);
- }
- /**
- * atomic64_set - set atomic64 variable
- * @v: pointer to type atomic64_t
- * @i: required value
- *
- * Atomically sets the value of @v to @i.
- */
- static inline void atomic64_set(atomic64_t *v, long i)
- {
- v->counter = i;
- }
- /**
- * 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 void atomic64_add(long i, atomic64_t *v)
- {
- asm volatile(LOCK_PREFIX "addq %1,%0"
- : "=m" (v->counter)
- : "er" (i), "m" (v->counter));
- }
- /**
- * atomic64_sub - subtract the atomic64 variable
- * @i: integer value to subtract
- * @v: pointer to type atomic64_t
- *
- * Atomically subtracts @i from @v.
- */
- static inline void atomic64_sub(long i, atomic64_t *v)
- {
- asm volatile(LOCK_PREFIX "subq %1,%0"
- : "=m" (v->counter)
- : "er" (i), "m" (v->counter));
- }
- /**
- * 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 i, atomic64_t *v)
- {
- unsigned char c;
- asm volatile(LOCK_PREFIX "subq %2,%0; sete %1"
- : "=m" (v->counter), "=qm" (c)
- : "er" (i), "m" (v->counter) : "memory");
- return c;
- }
- /**
- * 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(LOCK_PREFIX "incq %0"
- : "=m" (v->counter)
- : "m" (v->counter));
- }
- /**
- * atomic64_dec - decrement atomic64 variable
- * @v: pointer to type atomic64_t
- *
- * Atomically decrements @v by 1.
- */
- static inline void atomic64_dec(atomic64_t *v)
- {
- asm volatile(LOCK_PREFIX "decq %0"
- : "=m" (v->counter)
- : "m" (v->counter));
- }
- /**
- * 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)
- {
- unsigned char c;
- asm volatile(LOCK_PREFIX "decq %0; sete %1"
- : "=m" (v->counter), "=qm" (c)
- : "m" (v->counter) : "memory");
- return c != 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)
- {
- unsigned char c;
- asm volatile(LOCK_PREFIX "incq %0; sete %1"
- : "=m" (v->counter), "=qm" (c)
- : "m" (v->counter) : "memory");
- return c != 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 i, atomic64_t *v)
- {
- unsigned char c;
- asm volatile(LOCK_PREFIX "addq %2,%0; sets %1"
- : "=m" (v->counter), "=qm" (c)
- : "er" (i), "m" (v->counter) : "memory");
- return c;
- }
- /**
- * 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 atomic64_add_return(long i, atomic64_t *v)
- {
- return i + xadd(&v->counter, i);
- }
- static inline long atomic64_sub_return(long i, atomic64_t *v)
- {
- return atomic64_add_return(-i, v);
- }
- #define atomic64_inc_return(v) (atomic64_add_return(1, (v)))
- #define atomic64_dec_return(v) (atomic64_sub_return(1, (v)))
- static inline long atomic64_cmpxchg(atomic64_t *v, long old, long new)
- {
- return cmpxchg(&v->counter, old, new);
- }
- static inline long atomic64_xchg(atomic64_t *v, long new)
- {
- return xchg(&v->counter, new);
- }
- /**
- * 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 the old value of @v.
- */
- static inline int atomic64_add_unless(atomic64_t *v, long a, long u)
- {
- long c, old;
- c = atomic64_read(v);
- for (;;) {
- if (unlikely(c == (u)))
- break;
- old = atomic64_cmpxchg((v), c, c + (a));
- if (likely(old == c))
- break;
- c = old;
- }
- return c != (u);
- }
- #define atomic64_inc_not_zero(v) atomic64_add_unless((v), 1, 0)
- /*
- * atomic64_dec_if_positive - decrement by 1 if old value positive
- * @v: pointer of type atomic_t
- *
- * The function returns the old value of *v minus 1, even if
- * the atomic variable, v, was not decremented.
- */
- static inline long atomic64_dec_if_positive(atomic64_t *v)
- {
- long c, old, dec;
- c = atomic64_read(v);
- for (;;) {
- dec = c - 1;
- if (unlikely(dec < 0))
- break;
- old = atomic64_cmpxchg((v), c, dec);
- if (likely(old == c))
- break;
- c = old;
- }
- return dec;
- }
- #endif /* _ASM_X86_ATOMIC64_64_H */
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