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linux/include/asm-x86_64/local.h
Andrew Morton 2cf8d82d63 [PATCH] make local_t signed
local_t's were defined to be unsigned.  This increases confusion because
atomic_t's are signed.  The patch goes through and changes all implementations
to use signed longs throughout.

Also, x86-64 was using 32-bit quantities for the value passed into local_add()
and local_sub().  Fixed.

All (actually, both) existing users have been audited.

(Also s/__inline__/inline/ in x86_64/local.h)

Cc: Andi Kleen <ak@muc.de>
Cc: Benjamin LaHaise <bcrl@kvack.org>
Cc: Kyle McMartin <kyle@parisc-linux.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-31 12:18:55 -08:00

75 lines
1.9 KiB
C

#ifndef _ARCH_X8664_LOCAL_H
#define _ARCH_X8664_LOCAL_H
#include <linux/percpu.h>
typedef struct
{
volatile long counter;
} local_t;
#define LOCAL_INIT(i) { (i) }
#define local_read(v) ((v)->counter)
#define local_set(v,i) (((v)->counter) = (i))
static inline void local_inc(local_t *v)
{
__asm__ __volatile__(
"incq %0"
:"=m" (v->counter)
:"m" (v->counter));
}
static inline void local_dec(local_t *v)
{
__asm__ __volatile__(
"decq %0"
:"=m" (v->counter)
:"m" (v->counter));
}
static inline void local_add(long i, local_t *v)
{
__asm__ __volatile__(
"addq %1,%0"
:"=m" (v->counter)
:"ir" (i), "m" (v->counter));
}
static inline void local_sub(long i, local_t *v)
{
__asm__ __volatile__(
"subq %1,%0"
:"=m" (v->counter)
:"ir" (i), "m" (v->counter));
}
/* On x86-64 these are better than the atomic variants on SMP kernels
because they dont use a lock prefix. */
#define __local_inc(l) local_inc(l)
#define __local_dec(l) local_dec(l)
#define __local_add(i,l) local_add((i),(l))
#define __local_sub(i,l) local_sub((i),(l))
/* 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.
*
* This could be done better if we moved the per cpu data directly
* after GS.
*/
#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))
#define __cpu_local_inc(v) cpu_local_inc(v)
#define __cpu_local_dec(v) cpu_local_dec(v)
#define __cpu_local_add(i, v) cpu_local_add((i), (v))
#define __cpu_local_sub(i, v) cpu_local_sub((i), (v))
#endif /* _ARCH_I386_LOCAL_H */