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#ifndef _ASM_GENERIC_LOCAL_H
#define _ASM_GENERIC_LOCAL_H
#include <linux/percpu.h>
#include <linux/hardirq.h>
#include <asm/atomic.h>
#include <asm/types.h>
/*
* A signed long type for operations which are atomic for a single CPU.
* Usually used in combination with per-cpu variables.
*
* This is the default implementation, which uses atomic_long_t. Which is
* rather pointless. The whole point behind local_t is that some processors
* can perform atomic adds and subtracts in a manner which is atomic wrt IRQs
* running on this CPU. local_t allows exploitation of such capabilities.
*/
/* Implement in terms of atomics. */
/* Don't use typedef: don't want them to be mixed with atomic_t's. */
typedef struct
{
atomic_long_t a;
} local_t;
#define LOCAL_INIT(i) { ATOMIC_LONG_INIT(i) }
#define local_read(l) atomic_long_read(&(l)->a)
#define local_set(l,i) atomic_long_set((&(l)->a),(i))
#define local_inc(l) atomic_long_inc(&(l)->a)
#define local_dec(l) atomic_long_dec(&(l)->a)
#define local_add(i,l) atomic_long_add((i),(&(l)->a))
#define local_sub(i,l) atomic_long_sub((i),(&(l)->a))
/* Non-atomic variants, ie. preemption disabled and won't be touched
* in interrupt, etc. Some archs can optimize this case well. */
#define __local_inc(l) local_set((l), local_read(l) + 1)
#define __local_dec(l) local_set((l), local_read(l) - 1)
#define __local_add(i,l) local_set((l), local_read(l) + (i))
#define __local_sub(i,l) local_set((l), local_read(l) - (i))
/* 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 (eg. mystruct.foo), not an address.
*/
#define cpu_local_read(v) local_read(&__get_cpu_var(v))
#define cpu_local_set(v, i) local_set(&__get_cpu_var(v), (i))
#define cpu_local_inc(v) local_inc(&__get_cpu_var(v))
#define cpu_local_dec(v) local_dec(&__get_cpu_var(v))
#define cpu_local_add(i, v) local_add((i), &__get_cpu_var(v))
#define cpu_local_sub(i, v) local_sub((i), &__get_cpu_var(v))
/* Non-atomic increments, ie. preemption disabled and won't be touched
* in interrupt, etc. Some archs can optimize this case well.
*/
#define __cpu_local_inc(v) __local_inc(&__get_cpu_var(v))
#define __cpu_local_dec(v) __local_dec(&__get_cpu_var(v))
#define __cpu_local_add(i, v) __local_add((i), &__get_cpu_var(v))
#define __cpu_local_sub(i, v) __local_sub((i), &__get_cpu_var(v))
#endif /* _ASM_GENERIC_LOCAL_H */
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