diff options
Diffstat (limited to 'arch/x86/include/asm/atomic.h')
| -rw-r--r-- | arch/x86/include/asm/atomic.h | 35 |
1 files changed, 32 insertions, 3 deletions
diff --git a/arch/x86/include/asm/atomic.h b/arch/x86/include/asm/atomic.h index 3e8674288198..a58b99811105 100644 --- a/arch/x86/include/asm/atomic.h +++ b/arch/x86/include/asm/atomic.h @@ -171,6 +171,16 @@ static __always_inline int atomic_sub_return(int i, atomic_t *v) #define atomic_inc_return(v) (atomic_add_return(1, v)) #define atomic_dec_return(v) (atomic_sub_return(1, v)) +static __always_inline int atomic_fetch_add(int i, atomic_t *v) +{ + return xadd(&v->counter, i); +} + +static __always_inline int atomic_fetch_sub(int i, atomic_t *v) +{ + return xadd(&v->counter, -i); +} + static __always_inline int atomic_cmpxchg(atomic_t *v, int old, int new) { return cmpxchg(&v->counter, old, new); @@ -190,10 +200,29 @@ static inline void atomic_##op(int i, atomic_t *v) \ : "memory"); \ } -ATOMIC_OP(and) -ATOMIC_OP(or) -ATOMIC_OP(xor) +#define ATOMIC_FETCH_OP(op, c_op) \ +static inline int atomic_fetch_##op(int i, atomic_t *v) \ +{ \ + int old, val = atomic_read(v); \ + for (;;) { \ + old = atomic_cmpxchg(v, val, val c_op i); \ + if (old == val) \ + break; \ + val = old; \ + } \ + return old; \ +} + +#define ATOMIC_OPS(op, c_op) \ + ATOMIC_OP(op) \ + ATOMIC_FETCH_OP(op, c_op) + +ATOMIC_OPS(and, &) +ATOMIC_OPS(or , |) +ATOMIC_OPS(xor, ^) +#undef ATOMIC_OPS +#undef ATOMIC_FETCH_OP #undef ATOMIC_OP /** |