#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 */