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#ifndef __ASM_SH_ATOMIC_LLSC_H
#define __ASM_SH_ATOMIC_LLSC_H
/*
* 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.
*/
static inline void atomic_add(int i, atomic_t *v)
{
unsigned long tmp;
__asm__ __volatile__ (
"1: movli.l @%2, %0 ! atomic_add \n"
" add %1, %0 \n"
" movco.l %0, @%2 \n"
" bf 1b \n"
: "=&z" (tmp)
: "r" (i), "r" (&v->counter)
: "t");
}
static inline void atomic_sub(int i, atomic_t *v)
{
unsigned long tmp;
__asm__ __volatile__ (
"1: movli.l @%2, %0 ! atomic_sub \n"
" sub %1, %0 \n"
" movco.l %0, @%2 \n"
" bf 1b \n"
: "=&z" (tmp)
: "r" (i), "r" (&v->counter)
: "t");
}
/*
* SH-4A note:
*
* We basically get atomic_xxx_return() for free compared with
* atomic_xxx(). movli.l/movco.l require r0 due to the instruction
* encoding, so the retval is automatically set without having to
* do any special work.
*/
static inline int atomic_add_return(int i, atomic_t *v)
{
unsigned long temp;
__asm__ __volatile__ (
"1: movli.l @%2, %0 ! atomic_add_return \n"
" add %1, %0 \n"
" movco.l %0, @%2 \n"
" bf 1b \n"
" synco \n"
: "=&z" (temp)
: "r" (i), "r" (&v->counter)
: "t");
return temp;
}
static inline int atomic_sub_return(int i, atomic_t *v)
{
unsigned long temp;
__asm__ __volatile__ (
"1: movli.l @%2, %0 ! atomic_sub_return \n"
" sub %1, %0 \n"
" movco.l %0, @%2 \n"
" bf 1b \n"
" synco \n"
: "=&z" (temp)
: "r" (i), "r" (&v->counter)
: "t");
return temp;
}
static inline void atomic_clear_mask(unsigned int mask, atomic_t *v)
{
unsigned long tmp;
__asm__ __volatile__ (
"1: movli.l @%2, %0 ! atomic_clear_mask \n"
" and %1, %0 \n"
" movco.l %0, @%2 \n"
" bf 1b \n"
: "=&z" (tmp)
: "r" (~mask), "r" (&v->counter)
: "t");
}
static inline void atomic_set_mask(unsigned int mask, atomic_t *v)
{
unsigned long tmp;
__asm__ __volatile__ (
"1: movli.l @%2, %0 ! atomic_set_mask \n"
" or %1, %0 \n"
" movco.l %0, @%2 \n"
" bf 1b \n"
: "=&z" (tmp)
: "r" (mask), "r" (&v->counter)
: "t");
}
#define atomic_cmpxchg(v, o, n) (cmpxchg(&((v)->counter), (o), (n)))
/**
* 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 non-zero if @v was not @u, and zero otherwise.
*/
static inline int atomic_add_unless(atomic_t *v, int a, int u)
{
int c, old;
c = atomic_read(v);
for (;;) {
if (unlikely(c == (u)))
break;
old = atomic_cmpxchg((v), c, c + (a));
if (likely(old == c))
break;
c = old;
}
return c != (u);
}
#endif /* __ASM_SH_ATOMIC_LLSC_H */
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