mirror of
https://github.com/torvalds/linux.git
synced 2024-11-14 08:02:07 +00:00
1da177e4c3
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
198 lines
3.8 KiB
C
198 lines
3.8 KiB
C
/*
|
|
* PowerPC64 atomic operations
|
|
*
|
|
* Copyright (C) 2001 Paul Mackerras <paulus@au.ibm.com>, IBM
|
|
* Copyright (C) 2001 Anton Blanchard <anton@au.ibm.com>, IBM
|
|
*
|
|
* This program is free software; you can redistribute it and/or
|
|
* modify it under the terms of the GNU General Public License
|
|
* as published by the Free Software Foundation; either version
|
|
* 2 of the License, or (at your option) any later version.
|
|
*/
|
|
|
|
#ifndef _ASM_PPC64_ATOMIC_H_
|
|
#define _ASM_PPC64_ATOMIC_H_
|
|
|
|
#include <asm/memory.h>
|
|
|
|
typedef struct { volatile int counter; } atomic_t;
|
|
|
|
#define ATOMIC_INIT(i) { (i) }
|
|
|
|
#define atomic_read(v) ((v)->counter)
|
|
#define atomic_set(v,i) (((v)->counter) = (i))
|
|
|
|
static __inline__ void atomic_add(int a, atomic_t *v)
|
|
{
|
|
int t;
|
|
|
|
__asm__ __volatile__(
|
|
"1: lwarx %0,0,%3 # atomic_add\n\
|
|
add %0,%2,%0\n\
|
|
stwcx. %0,0,%3\n\
|
|
bne- 1b"
|
|
: "=&r" (t), "=m" (v->counter)
|
|
: "r" (a), "r" (&v->counter), "m" (v->counter)
|
|
: "cc");
|
|
}
|
|
|
|
static __inline__ int atomic_add_return(int a, atomic_t *v)
|
|
{
|
|
int t;
|
|
|
|
__asm__ __volatile__(
|
|
EIEIO_ON_SMP
|
|
"1: lwarx %0,0,%2 # atomic_add_return\n\
|
|
add %0,%1,%0\n\
|
|
stwcx. %0,0,%2\n\
|
|
bne- 1b"
|
|
ISYNC_ON_SMP
|
|
: "=&r" (t)
|
|
: "r" (a), "r" (&v->counter)
|
|
: "cc", "memory");
|
|
|
|
return t;
|
|
}
|
|
|
|
#define atomic_add_negative(a, v) (atomic_add_return((a), (v)) < 0)
|
|
|
|
static __inline__ void atomic_sub(int a, atomic_t *v)
|
|
{
|
|
int t;
|
|
|
|
__asm__ __volatile__(
|
|
"1: lwarx %0,0,%3 # atomic_sub\n\
|
|
subf %0,%2,%0\n\
|
|
stwcx. %0,0,%3\n\
|
|
bne- 1b"
|
|
: "=&r" (t), "=m" (v->counter)
|
|
: "r" (a), "r" (&v->counter), "m" (v->counter)
|
|
: "cc");
|
|
}
|
|
|
|
static __inline__ int atomic_sub_return(int a, atomic_t *v)
|
|
{
|
|
int t;
|
|
|
|
__asm__ __volatile__(
|
|
EIEIO_ON_SMP
|
|
"1: lwarx %0,0,%2 # atomic_sub_return\n\
|
|
subf %0,%1,%0\n\
|
|
stwcx. %0,0,%2\n\
|
|
bne- 1b"
|
|
ISYNC_ON_SMP
|
|
: "=&r" (t)
|
|
: "r" (a), "r" (&v->counter)
|
|
: "cc", "memory");
|
|
|
|
return t;
|
|
}
|
|
|
|
static __inline__ void atomic_inc(atomic_t *v)
|
|
{
|
|
int t;
|
|
|
|
__asm__ __volatile__(
|
|
"1: lwarx %0,0,%2 # atomic_inc\n\
|
|
addic %0,%0,1\n\
|
|
stwcx. %0,0,%2\n\
|
|
bne- 1b"
|
|
: "=&r" (t), "=m" (v->counter)
|
|
: "r" (&v->counter), "m" (v->counter)
|
|
: "cc");
|
|
}
|
|
|
|
static __inline__ int atomic_inc_return(atomic_t *v)
|
|
{
|
|
int t;
|
|
|
|
__asm__ __volatile__(
|
|
EIEIO_ON_SMP
|
|
"1: lwarx %0,0,%1 # atomic_inc_return\n\
|
|
addic %0,%0,1\n\
|
|
stwcx. %0,0,%1\n\
|
|
bne- 1b"
|
|
ISYNC_ON_SMP
|
|
: "=&r" (t)
|
|
: "r" (&v->counter)
|
|
: "cc", "memory");
|
|
|
|
return t;
|
|
}
|
|
|
|
/*
|
|
* atomic_inc_and_test - increment and test
|
|
* @v: pointer of type atomic_t
|
|
*
|
|
* Atomically increments @v by 1
|
|
* and returns true if the result is zero, or false for all
|
|
* other cases.
|
|
*/
|
|
#define atomic_inc_and_test(v) (atomic_inc_return(v) == 0)
|
|
|
|
static __inline__ void atomic_dec(atomic_t *v)
|
|
{
|
|
int t;
|
|
|
|
__asm__ __volatile__(
|
|
"1: lwarx %0,0,%2 # atomic_dec\n\
|
|
addic %0,%0,-1\n\
|
|
stwcx. %0,0,%2\n\
|
|
bne- 1b"
|
|
: "=&r" (t), "=m" (v->counter)
|
|
: "r" (&v->counter), "m" (v->counter)
|
|
: "cc");
|
|
}
|
|
|
|
static __inline__ int atomic_dec_return(atomic_t *v)
|
|
{
|
|
int t;
|
|
|
|
__asm__ __volatile__(
|
|
EIEIO_ON_SMP
|
|
"1: lwarx %0,0,%1 # atomic_dec_return\n\
|
|
addic %0,%0,-1\n\
|
|
stwcx. %0,0,%1\n\
|
|
bne- 1b"
|
|
ISYNC_ON_SMP
|
|
: "=&r" (t)
|
|
: "r" (&v->counter)
|
|
: "cc", "memory");
|
|
|
|
return t;
|
|
}
|
|
|
|
#define atomic_sub_and_test(a, v) (atomic_sub_return((a), (v)) == 0)
|
|
#define atomic_dec_and_test(v) (atomic_dec_return((v)) == 0)
|
|
|
|
/*
|
|
* Atomically test *v and decrement if it is greater than 0.
|
|
* The function returns the old value of *v minus 1.
|
|
*/
|
|
static __inline__ int atomic_dec_if_positive(atomic_t *v)
|
|
{
|
|
int t;
|
|
|
|
__asm__ __volatile__(
|
|
EIEIO_ON_SMP
|
|
"1: lwarx %0,0,%1 # atomic_dec_if_positive\n\
|
|
addic. %0,%0,-1\n\
|
|
blt- 2f\n\
|
|
stwcx. %0,0,%1\n\
|
|
bne- 1b"
|
|
ISYNC_ON_SMP
|
|
"\n\
|
|
2:" : "=&r" (t)
|
|
: "r" (&v->counter)
|
|
: "cc", "memory");
|
|
|
|
return t;
|
|
}
|
|
|
|
#define smp_mb__before_atomic_dec() smp_mb()
|
|
#define smp_mb__after_atomic_dec() smp_mb()
|
|
#define smp_mb__before_atomic_inc() smp_mb()
|
|
#define smp_mb__after_atomic_inc() smp_mb()
|
|
|
|
#endif /* _ASM_PPC64_ATOMIC_H_ */
|