]>
git.proxmox.com Git - mirror_ubuntu-artful-kernel.git/blob - arch/x86/include/asm/atomic64_64.h
1 #ifndef _ASM_X86_ATOMIC64_64_H
2 #define _ASM_X86_ATOMIC64_64_H
4 #include <linux/types.h>
5 #include <asm/alternative.h>
6 #include <asm/cmpxchg.h>
8 /* The 64-bit atomic type */
10 #define ATOMIC64_INIT(i) { (i) }
13 * atomic64_read - read atomic64 variable
14 * @v: pointer of type atomic64_t
16 * Atomically reads the value of @v.
17 * Doesn't imply a read memory barrier.
19 static inline long atomic64_read(const atomic64_t
*v
)
21 return READ_ONCE((v
)->counter
);
25 * atomic64_set - set atomic64 variable
26 * @v: pointer to type atomic64_t
29 * Atomically sets the value of @v to @i.
31 static inline void atomic64_set(atomic64_t
*v
, long i
)
33 WRITE_ONCE(v
->counter
, i
);
37 * atomic64_add - add integer to atomic64 variable
38 * @i: integer value to add
39 * @v: pointer to type atomic64_t
41 * Atomically adds @i to @v.
43 static __always_inline
void atomic64_add(long i
, atomic64_t
*v
)
45 asm volatile(LOCK_PREFIX
"addq %1,%0"
47 : "er" (i
), "m" (v
->counter
));
51 * atomic64_sub - subtract the atomic64 variable
52 * @i: integer value to subtract
53 * @v: pointer to type atomic64_t
55 * Atomically subtracts @i from @v.
57 static inline void atomic64_sub(long i
, atomic64_t
*v
)
59 asm volatile(LOCK_PREFIX
"subq %1,%0"
61 : "er" (i
), "m" (v
->counter
));
65 * atomic64_sub_and_test - subtract value from variable and test result
66 * @i: integer value to subtract
67 * @v: pointer to type atomic64_t
69 * Atomically subtracts @i from @v and returns
70 * true if the result is zero, or false for all
73 static inline bool atomic64_sub_and_test(long i
, atomic64_t
*v
)
75 GEN_BINARY_RMWcc(LOCK_PREFIX
"subq", v
->counter
, "er", i
, "%0", e
);
79 * atomic64_inc - increment atomic64 variable
80 * @v: pointer to type atomic64_t
82 * Atomically increments @v by 1.
84 static __always_inline
void atomic64_inc(atomic64_t
*v
)
86 asm volatile(LOCK_PREFIX
"incq %0"
92 * atomic64_dec - decrement atomic64 variable
93 * @v: pointer to type atomic64_t
95 * Atomically decrements @v by 1.
97 static __always_inline
void atomic64_dec(atomic64_t
*v
)
99 asm volatile(LOCK_PREFIX
"decq %0"
105 * atomic64_dec_and_test - decrement and test
106 * @v: pointer to type atomic64_t
108 * Atomically decrements @v by 1 and
109 * returns true if the result is 0, or false for all other
112 static inline bool atomic64_dec_and_test(atomic64_t
*v
)
114 GEN_UNARY_RMWcc(LOCK_PREFIX
"decq", v
->counter
, "%0", e
);
118 * atomic64_inc_and_test - increment and test
119 * @v: pointer to type atomic64_t
121 * Atomically increments @v by 1
122 * and returns true if the result is zero, or false for all
125 static inline bool atomic64_inc_and_test(atomic64_t
*v
)
127 GEN_UNARY_RMWcc(LOCK_PREFIX
"incq", v
->counter
, "%0", e
);
131 * atomic64_add_negative - add and test if negative
132 * @i: integer value to add
133 * @v: pointer to type atomic64_t
135 * Atomically adds @i to @v and returns true
136 * if the result is negative, or false when
137 * result is greater than or equal to zero.
139 static inline bool atomic64_add_negative(long i
, atomic64_t
*v
)
141 GEN_BINARY_RMWcc(LOCK_PREFIX
"addq", v
->counter
, "er", i
, "%0", s
);
145 * atomic64_add_return - add and return
146 * @i: integer value to add
147 * @v: pointer to type atomic64_t
149 * Atomically adds @i to @v and returns @i + @v
151 static __always_inline
long atomic64_add_return(long i
, atomic64_t
*v
)
153 return i
+ xadd(&v
->counter
, i
);
156 static inline long atomic64_sub_return(long i
, atomic64_t
*v
)
158 return atomic64_add_return(-i
, v
);
161 static inline long atomic64_fetch_add(long i
, atomic64_t
*v
)
163 return xadd(&v
->counter
, i
);
166 static inline long atomic64_fetch_sub(long i
, atomic64_t
*v
)
168 return xadd(&v
->counter
, -i
);
171 #define atomic64_inc_return(v) (atomic64_add_return(1, (v)))
172 #define atomic64_dec_return(v) (atomic64_sub_return(1, (v)))
174 static inline long atomic64_cmpxchg(atomic64_t
*v
, long old
, long new)
176 return cmpxchg(&v
->counter
, old
, new);
179 #define atomic64_try_cmpxchg atomic64_try_cmpxchg
180 static __always_inline
bool atomic64_try_cmpxchg(atomic64_t
*v
, long *old
, long new)
182 return try_cmpxchg(&v
->counter
, old
, new);
185 static inline long atomic64_xchg(atomic64_t
*v
, long new)
187 return xchg(&v
->counter
, new);
191 * atomic64_add_unless - add unless the number is a given value
192 * @v: pointer of type atomic64_t
193 * @a: the amount to add to v...
194 * @u: ...unless v is equal to u.
196 * Atomically adds @a to @v, so long as it was not @u.
197 * Returns the old value of @v.
199 static inline bool atomic64_add_unless(atomic64_t
*v
, long a
, long u
)
201 long c
= atomic64_read(v
);
203 if (unlikely(c
== u
))
205 } while (!atomic64_try_cmpxchg(v
, &c
, c
+ a
));
209 #define atomic64_inc_not_zero(v) atomic64_add_unless((v), 1, 0)
212 * atomic64_dec_if_positive - decrement by 1 if old value positive
213 * @v: pointer of type atomic_t
215 * The function returns the old value of *v minus 1, even if
216 * the atomic variable, v, was not decremented.
218 static inline long atomic64_dec_if_positive(atomic64_t
*v
)
220 long dec
, c
= atomic64_read(v
);
223 if (unlikely(dec
< 0))
225 } while (!atomic64_try_cmpxchg(v
, &c
, dec
));
229 #define ATOMIC64_OP(op) \
230 static inline void atomic64_##op(long i, atomic64_t *v) \
232 asm volatile(LOCK_PREFIX #op"q %1,%0" \
233 : "+m" (v->counter) \
238 #define ATOMIC64_FETCH_OP(op, c_op) \
239 static inline long atomic64_fetch_##op(long i, atomic64_t *v) \
241 long val = atomic64_read(v); \
243 } while (!atomic64_try_cmpxchg(v, &val, val c_op i)); \
247 #define ATOMIC64_OPS(op, c_op) \
249 ATOMIC64_FETCH_OP(op, c_op)
256 #undef ATOMIC64_FETCH_OP
259 #endif /* _ASM_X86_ATOMIC64_64_H */