sparc32: drop unused atomic24 support

atomic24 support was used to semaphores in the past - but is no longer used.

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Sam Ravnborg
2011-12-26 20:57:22 +01:00
committed by David S. Miller
parent 371de6e4e0
commit 348738afe5
3 changed files with 0 additions and 161 deletions

View File

@@ -52,106 +52,6 @@ extern void atomic_set(atomic_t *, int);
#define atomic_dec_and_test(v) (atomic_dec_return(v) == 0)
#define atomic_sub_and_test(i, v) (atomic_sub_return(i, v) == 0)
/* This is the old 24-bit implementation. It's still used internally
* by some sparc-specific code, notably the semaphore implementation.
*/
typedef struct { volatile int counter; } atomic24_t;
#ifndef CONFIG_SMP
#define ATOMIC24_INIT(i) { (i) }
#define atomic24_read(v) ((v)->counter)
#define atomic24_set(v, i) (((v)->counter) = i)
#else
/* We do the bulk of the actual work out of line in two common
* routines in assembler, see arch/sparc/lib/atomic.S for the
* "fun" details.
*
* For SMP the trick is you embed the spin lock byte within
* the word, use the low byte so signedness is easily retained
* via a quick arithmetic shift. It looks like this:
*
* ----------------------------------------
* | signed 24-bit counter value | lock | atomic_t
* ----------------------------------------
* 31 8 7 0
*/
#define ATOMIC24_INIT(i) { ((i) << 8) }
static inline int atomic24_read(const atomic24_t *v)
{
int ret = v->counter;
while(ret & 0xff)
ret = v->counter;
return ret >> 8;
}
#define atomic24_set(v, i) (((v)->counter) = ((i) << 8))
#endif
static inline int __atomic24_add(int i, atomic24_t *v)
{
register volatile int *ptr asm("g1");
register int increment asm("g2");
register int tmp1 asm("g3");
register int tmp2 asm("g4");
register int tmp3 asm("g7");
ptr = &v->counter;
increment = i;
__asm__ __volatile__(
"mov %%o7, %%g4\n\t"
"call ___atomic24_add\n\t"
" add %%o7, 8, %%o7\n"
: "=&r" (increment), "=r" (tmp1), "=r" (tmp2), "=r" (tmp3)
: "0" (increment), "r" (ptr)
: "memory", "cc");
return increment;
}
static inline int __atomic24_sub(int i, atomic24_t *v)
{
register volatile int *ptr asm("g1");
register int increment asm("g2");
register int tmp1 asm("g3");
register int tmp2 asm("g4");
register int tmp3 asm("g7");
ptr = &v->counter;
increment = i;
__asm__ __volatile__(
"mov %%o7, %%g4\n\t"
"call ___atomic24_sub\n\t"
" add %%o7, 8, %%o7\n"
: "=&r" (increment), "=r" (tmp1), "=r" (tmp2), "=r" (tmp3)
: "0" (increment), "r" (ptr)
: "memory", "cc");
return increment;
}
#define atomic24_add(i, v) ((void)__atomic24_add((i), (v)))
#define atomic24_sub(i, v) ((void)__atomic24_sub((i), (v)))
#define atomic24_dec_return(v) __atomic24_sub(1, (v))
#define atomic24_inc_return(v) __atomic24_add(1, (v))
#define atomic24_sub_and_test(i, v) (__atomic24_sub((i), (v)) == 0)
#define atomic24_dec_and_test(v) (__atomic24_sub(1, (v)) == 0)
#define atomic24_inc(v) ((void)__atomic24_add(1, (v)))
#define atomic24_dec(v) ((void)__atomic24_sub(1, (v)))
#define atomic24_add_negative(i, v) (__atomic24_add((i), (v)) < 0)
/* Atomic operations are already serializing */
#define smp_mb__before_atomic_dec() barrier()
#define smp_mb__after_atomic_dec() barrier()