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#ifndef _ALPHA_ATOMIC_H
#define _ALPHA_ATOMIC_H
#include <linux/types.h>
#include <asm/barrier.h>
#include <asm/cmpxchg.h>
/*
* Atomic operations that C can't guarantee us. Useful for
* resource counting etc...
*
* But use these as seldom as possible since they are much slower
* than regular operations.
*/
#define ATOMIC_INIT(i) { (i) }
#define ATOMIC64_INIT(i) { (i) }
#define atomic_read(v) ACCESS_ONCE((v)->counter)
#define atomic64_read(v) ACCESS_ONCE((v)->counter)
#define atomic_set(v,i) ((v)->counter = (i))
#define atomic64_set(v,i) ((v)->counter = (i))
/*
* To get proper branch prediction for the main line, we must branch
* forward to code at the end of this object's .text section, then
* branch back to restart the operation.
*/
#define ATOMIC_OP(op) \
static __inline__ void atomic_##op(int i, atomic_t * v) \
{ \
unsigned long temp; \
__asm__ __volatile__( \
"1: ldl_l %0,%1\n" \
" " #op "l %0,%2,%0\n" \
" stl_c %0,%1\n" \
" beq %0,2f\n" \
".subsection 2\n" \
"2: br 1b\n" \
".previous" \
:"=&r" (temp), "=m" (v->counter) \
:"Ir" (i), "m" (v->counter)); \
} \
#define ATOMIC_OP_RETURN(op) \
static inline int atomic_##op##_return(int i, atomic_t *v) \
{ \
long temp, result; \
smp_mb(); \
__asm__ __volatile__( \
"1: ldl_l %0,%1\n" \
" " #op "l %0,%3,%2\n" \
" " #op "l %0,%3,%0\n" \
" stl_c %0,%1\n" \
" beq %0,2f\n" \
".subsection 2\n" \
"2: br 1b\n" \
".previous" \
:"=&r" (temp), "=m" (v->counter), "=&r" (result) \
:"Ir" (i), "m" (v->counter) : "memory"); \
smp_mb(); \
return result; \
}
#define ATOMIC64_OP(op) \
static __inline__ void atomic64_##op(long i, atomic64_t * v) \
{ \
unsigned long temp; \
__asm__ __volatile__( \
"1: ldq_l %0,%1\n" \
" " #op "q %0,%2,%0\n" \
" stq_c %0,%1\n" \
" beq %0,2f\n" \
".subsection 2\n" \
"2: br 1b\n" \
".previous" \
:"=&r" (temp), "=m" (v->counter) \
:"Ir" (i), "m" (v->counter)); \
} \
#define ATOMIC64_OP_RETURN(op) \
static __inline__ long atomic64_##op##_return(long i, atomic64_t * v) \
{ \
long temp, result; \
smp_mb(); \
__asm__ __volatile__( \
"1: ldq_l %0,%1\n" \
" " #op "q %0,%3,%2\n" \
" " #op "q %0,%3,%0\n" \
" stq_c %0,%1\n" \
" beq %0,2f\n" \
".subsection 2\n" \
"2: br 1b\n" \
".previous" \
:"=&r" (temp), "=m" (v->counter), "=&r" (result) \
:"Ir" (i), "m" (v->counter) : "memory"); \
smp_mb(); \
return result; \
}
#define ATOMIC_OPS(opg) \
ATOMIC_OP(opg) \
ATOMIC_OP_RETURN(opg) \
ATOMIC64_OP(opg) \
ATOMIC64_OP_RETURN(opg)
ATOMIC_OPS(add)
ATOMIC_OPS(sub)
#undef ATOMIC_OPS
#undef ATOMIC64_OP_RETURN
#undef ATOMIC64_OP
#undef ATOMIC_OP_RETURN
#undef ATOMIC_OP
#define atomic64_cmpxchg(v, old, new) (cmpxchg(&((v)->counter), old, new))
#define atomic64_xchg(v, new) (xchg(&((v)->counter), new))
#define atomic_cmpxchg(v, old, new) (cmpxchg(&((v)->counter), old, new))
#define atomic_xchg(v, new) (xchg(&((v)->counter), new))
/**
* __atomic_add_unless - add unless the number is a given value
* @v: pointer of type atomic_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 __atomic_add_unless(atomic_t *v, int a, int u)
{
int c, new, old;
smp_mb();
__asm__ __volatile__(
"1: ldl_l %[old],%[mem]\n"
" cmpeq %[old],%[u],%[c]\n"
" addl %[old],%[a],%[new]\n"
" bne %[c],2f\n"
" stl_c %[new],%[mem]\n"
" beq %[new],3f\n"
"2:\n"
".subsection 2\n"
"3: br 1b\n"
".previous"
: [old] "=&r"(old), [new] "=&r"(new), [c] "=&r"(c)
: [mem] "m"(*v), [a] "rI"(a), [u] "rI"((long)u)
: "memory");
smp_mb();
return old;
}
/**
* 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 true iff @v was not @u.
*/
static __inline__ int atomic64_add_unless(atomic64_t *v, long a, long u)
{
long c, tmp;
smp_mb();
__asm__ __volatile__(
"1: ldq_l %[tmp],%[mem]\n"
" cmpeq %[tmp],%[u],%[c]\n"
" addq %[tmp],%[a],%[tmp]\n"
" bne %[c],2f\n"
" stq_c %[tmp],%[mem]\n"
" beq %[tmp],3f\n"
"2:\n"
".subsection 2\n"
"3: br 1b\n"
".previous"
: [tmp] "=&r"(tmp), [c] "=&r"(c)
: [mem] "m"(*v), [a] "rI"(a), [u] "rI"(u)
: "memory");
smp_mb();
return !c;
}
/*
* 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 old, tmp;
smp_mb();
__asm__ __volatile__(
"1: ldq_l %[old],%[mem]\n"
" subq %[old],1,%[tmp]\n"
" ble %[old],2f\n"
" stq_c %[tmp],%[mem]\n"
" beq %[tmp],3f\n"
"2:\n"
".subsection 2\n"
"3: br 1b\n"
".previous"
: [old] "=&r"(old), [tmp] "=&r"(tmp)
: [mem] "m"(*v)
: "memory");
smp_mb();
return old - 1;
}
#define atomic64_inc_not_zero(v) atomic64_add_unless((v), 1, 0)
#define atomic_add_negative(a, v) (atomic_add_return((a), (v)) < 0)
#define atomic64_add_negative(a, v) (atomic64_add_return((a), (v)) < 0)
#define atomic_dec_return(v) atomic_sub_return(1,(v))
#define atomic64_dec_return(v) atomic64_sub_return(1,(v))
#define atomic_inc_return(v) atomic_add_return(1,(v))
#define atomic64_inc_return(v) atomic64_add_return(1,(v))
#define atomic_sub_and_test(i,v) (atomic_sub_return((i), (v)) == 0)
#define atomic64_sub_and_test(i,v) (atomic64_sub_return((i), (v)) == 0)
#define atomic_inc_and_test(v) (atomic_add_return(1, (v)) == 0)
#define atomic64_inc_and_test(v) (atomic64_add_return(1, (v)) == 0)
#define atomic_dec_and_test(v) (atomic_sub_return(1, (v)) == 0)
#define atomic64_dec_and_test(v) (atomic64_sub_return(1, (v)) == 0)
#define atomic_inc(v) atomic_add(1,(v))
#define atomic64_inc(v) atomic64_add(1,(v))
#define atomic_dec(v) atomic_sub(1,(v))
#define atomic64_dec(v) atomic64_sub(1,(v))
#endif /* _ALPHA_ATOMIC_H */
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