/* * 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_ */