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#ifndef _ARCH_POWERPC_LOCAL_H
#define _ARCH_POWERPC_LOCAL_H
#include <linux/percpu.h>
#include <asm/atomic.h>
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_add(i,l) atomic_long_add((i),(&(l)->a))
#define local_sub(i,l) atomic_long_sub((i),(&(l)->a))
#define local_inc(l) atomic_long_inc(&(l)->a)
#define local_dec(l) atomic_long_dec(&(l)->a)
static __inline__ long local_add_return(long a, local_t *l)
{
long t;
__asm__ __volatile__(
"1:" PPC_LLARX "%0,0,%2 # local_add_return\n\
add %0,%1,%0\n"
PPC405_ERR77(0,%2)
PPC_STLCX "%0,0,%2 \n\
bne- 1b"
: "=&r" (t)
: "r" (a), "r" (&(l->a.counter))
: "cc", "memory");
return t;
}
#define local_add_negative(a, l) (local_add_return((a), (l)) < 0)
static __inline__ long local_sub_return(long a, local_t *l)
{
long t;
__asm__ __volatile__(
"1:" PPC_LLARX "%0,0,%2 # local_sub_return\n\
subf %0,%1,%0\n"
PPC405_ERR77(0,%2)
PPC_STLCX "%0,0,%2 \n\
bne- 1b"
: "=&r" (t)
: "r" (a), "r" (&(l->a.counter))
: "cc", "memory");
return t;
}
static __inline__ long local_inc_return(local_t *l)
{
long t;
__asm__ __volatile__(
"1:" PPC_LLARX "%0,0,%1 # local_inc_return\n\
addic %0,%0,1\n"
PPC405_ERR77(0,%1)
PPC_STLCX "%0,0,%1 \n\
bne- 1b"
: "=&r" (t)
: "r" (&(l->a.counter))
: "cc", "memory");
return t;
}
/*
* local_inc_and_test - increment and test
* @l: pointer of type local_t
*
* Atomically increments @l by 1
* and returns true if the result is zero, or false for all
* other cases.
*/
#define local_inc_and_test(l) (local_inc_return(l) == 0)
static __inline__ long local_dec_return(local_t *l)
{
long t;
__asm__ __volatile__(
"1:" PPC_LLARX "%0,0,%1 # local_dec_return\n\
addic %0,%0,-1\n"
PPC405_ERR77(0,%1)
PPC_STLCX "%0,0,%1\n\
bne- 1b"
: "=&r" (t)
: "r" (&(l->a.counter))
: "cc", "memory");
return t;
}
#define local_cmpxchg(l, o, n) \
(cmpxchg_local(&((l)->a.counter), (o), (n)))
#define local_xchg(l, n) (xchg_local(&((l)->a.counter), (n)))
/**
* local_add_unless - add unless the number is a given value
* @l: pointer of type local_t
* @a: the amount to add to v...
* @u: ...unless v is equal to u.
*
* Atomically adds @a to @l, so long as it was not @u.
* Returns non-zero if @l was not @u, and zero otherwise.
*/
static __inline__ int local_add_unless(local_t *l, long a, long u)
{
long t;
__asm__ __volatile__ (
"1:" PPC_LLARX "%0,0,%1 # local_add_unless\n\
cmpw 0,%0,%3 \n\
beq- 2f \n\
add %0,%2,%0 \n"
PPC405_ERR77(0,%2)
PPC_STLCX "%0,0,%1 \n\
bne- 1b \n"
" subf %0,%2,%0 \n\
2:"
: "=&r" (t)
: "r" (&(l->a.counter)), "r" (a), "r" (u)
: "cc", "memory");
return t != u;
}
#define local_inc_not_zero(l) local_add_unless((l), 1, 0)
#define local_sub_and_test(a, l) (local_sub_return((a), (l)) == 0)
#define local_dec_and_test(l) (local_dec_return((l)) == 0)
/*
* Atomically test *l and decrement if it is greater than 0.
* The function returns the old value of *l minus 1.
*/
static __inline__ long local_dec_if_positive(local_t *l)
{
long t;
__asm__ __volatile__(
"1:" PPC_LLARX "%0,0,%1 # local_dec_if_positive\n\
cmpwi %0,1\n\
addi %0,%0,-1\n\
blt- 2f\n"
PPC405_ERR77(0,%1)
PPC_STLCX "%0,0,%1\n\
bne- 1b"
"\n\
2:" : "=&b" (t)
: "r" (&(l->a.counter))
: "cc", "memory");
return t;
}
/* 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.
*/
#define __local_inc(l) ((l)->a.counter++)
#define __local_dec(l) ((l)->a.counter++)
#define __local_add(i,l) ((l)->a.counter+=(i))
#define __local_sub(i,l) ((l)->a.counter-=(i))
/* 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(l) \
({ local_t res__; \
preempt_disable(); \
res__ = (l); \
preempt_enable(); \
res__; })
#define cpu_local_wrap(l) \
({ preempt_disable(); \
l; \
preempt_enable(); }) \
#define cpu_local_read(l) cpu_local_wrap_v(local_read(&__get_cpu_var(l)))
#define cpu_local_set(l, i) cpu_local_wrap(local_set(&__get_cpu_var(l), (i)))
#define cpu_local_inc(l) cpu_local_wrap(local_inc(&__get_cpu_var(l)))
#define cpu_local_dec(l) cpu_local_wrap(local_dec(&__get_cpu_var(l)))
#define cpu_local_add(i, l) cpu_local_wrap(local_add((i), &__get_cpu_var(l)))
#define cpu_local_sub(i, l) cpu_local_wrap(local_sub((i), &__get_cpu_var(l)))
#define __cpu_local_inc(l) cpu_local_inc(l)
#define __cpu_local_dec(l) cpu_local_dec(l)
#define __cpu_local_add(i, l) cpu_local_add((i), (l))
#define __cpu_local_sub(i, l) cpu_local_sub((i), (l))
#endif /* _ARCH_POWERPC_LOCAL_H */
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