blob: e769e620022530c751a244f1b83e301d683d1d2a [file] [log] [blame]
#ifndef _ARCH_X8664_LOCAL_H
#define _ARCH_X8664_LOCAL_H
#include <linux/percpu.h>
typedef struct
volatile long counter;
} local_t;
#define LOCAL_INIT(i) { (i) }
#define local_read(v) ((v)->counter)
#define local_set(v,i) (((v)->counter) = (i))
static inline void local_inc(local_t *v)
__asm__ __volatile__(
"incq %0"
:"=m" (v->counter)
:"m" (v->counter));
static inline void local_dec(local_t *v)
__asm__ __volatile__(
"decq %0"
:"=m" (v->counter)
:"m" (v->counter));
static inline void local_add(long i, local_t *v)
__asm__ __volatile__(
"addq %1,%0"
:"=m" (v->counter)
:"ir" (i), "m" (v->counter));
static inline void local_sub(long i, local_t *v)
__asm__ __volatile__(
"subq %1,%0"
:"=m" (v->counter)
:"ir" (i), "m" (v->counter));
/* On x86-64 these are better than the atomic variants on SMP kernels
because they dont use a lock prefix. */
#define __local_inc(l) local_inc(l)
#define __local_dec(l) local_dec(l)
#define __local_add(i,l) local_add((i),(l))
#define __local_sub(i,l) local_sub((i),(l))
/* Use these for per-cpu local_t variables: on some archs they are
* much more efficient than these naive implementations. Note they take
* a variable, not an address.
* This could be done better if we moved the per cpu data directly
* after GS.
/* Need to disable preemption for the cpu local counters otherwise we could
still access a variable of a previous CPU in a non atomic way. */
#define cpu_local_wrap_v(v) \
({ local_t res__; \
preempt_disable(); \
res__ = (v); \
preempt_enable(); \
res__; })
#define cpu_local_wrap(v) \
({ preempt_disable(); \
v; \
preempt_enable(); }) \
#define cpu_local_read(v) cpu_local_wrap_v(local_read(&__get_cpu_var(v)))
#define cpu_local_set(v, i) cpu_local_wrap(local_set(&__get_cpu_var(v), (i)))
#define cpu_local_inc(v) cpu_local_wrap(local_inc(&__get_cpu_var(v)))
#define cpu_local_dec(v) cpu_local_wrap(local_dec(&__get_cpu_var(v)))
#define cpu_local_add(i, v) cpu_local_wrap(local_add((i), &__get_cpu_var(v)))
#define cpu_local_sub(i, v) cpu_local_wrap(local_sub((i), &__get_cpu_var(v)))
#define __cpu_local_inc(v) cpu_local_inc(v)
#define __cpu_local_dec(v) cpu_local_dec(v)
#define __cpu_local_add(i, v) cpu_local_add((i), (v))
#define __cpu_local_sub(i, v) cpu_local_sub((i), (v))
#endif /* _ARCH_I386_LOCAL_H */