/* * Copyright 2010 Tilera Corporation. All Rights Reserved. * *   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, version 2. * *   This program is distributed in the hope that it will be useful, but *   WITHOUT ANY WARRANTY; without even the implied warranty of *   MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or *   NON INFRINGEMENT.  See the GNU General Public License for *   more details. * * Atomic primitives. */ #ifndef _ASM_TILE_ATOMIC_H#define _ASM_TILE_ATOMIC_H #include <asm/cmpxchg.h> #ifndef __ASSEMBLY__ #include <linux/compiler.h>#include <linux/types.h> #define ATOMIC_INIT(i)	{ (i) } /** * atomic_read - read atomic variable * @v: pointer of type atomic_t * * Atomically reads the value of @v. */static inline int atomic_read(const atomic_t *v){	return ACCESS_ONCE(v->counter);} /** * atomic_sub_return - subtract integer and return * @v: pointer of type atomic_t * @i: integer value to subtract * * Atomically subtracts @i from @v and returns @v - @i */#define atomic_sub_return(i, v)		atomic_add_return((int)(-(i)), (v)) /** * atomic_sub - subtract integer from atomic variable * @i: integer value to subtract * @v: pointer of type atomic_t * * Atomically subtracts @i from @v. */#define atomic_sub(i, v)		atomic_add((int)(-(i)), (v)) /** * atomic_sub_and_test - subtract value from variable and test result * @i: integer value to subtract * @v: pointer of type atomic_t * * Atomically subtracts @i from @v and returns true if the result is * zero, or false for all other cases. */#define atomic_sub_and_test(i, v)	(atomic_sub_return((i), (v)) == 0) /** * atomic_inc_return - increment memory and return * @v: pointer of type atomic_t * * Atomically increments @v by 1 and returns the new value. */#define atomic_inc_return(v)		atomic_add_return(1, (v)) /** * atomic_dec_return - decrement memory and return * @v: pointer of type atomic_t * * Atomically decrements @v by 1 and returns the new value. */#define atomic_dec_return(v)		atomic_sub_return(1, (v)) /** * atomic_inc - increment atomic variable * @v: pointer of type atomic_t * * Atomically increments @v by 1. */#define atomic_inc(v)			atomic_add(1, (v)) /** * atomic_dec - decrement atomic variable * @v: pointer of type atomic_t * * Atomically decrements @v by 1. */#define atomic_dec(v)			atomic_sub(1, (v)) /** * atomic_dec_and_test - decrement and test * @v: pointer of type atomic_t * * Atomically decrements @v by 1 and returns true if the result is 0. */#define atomic_dec_and_test(v)		(atomic_dec_return(v) == 0) /** * 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 0. */#define atomic_inc_and_test(v)		(atomic_inc_return(v) == 0) /** * atomic_xchg - atomically exchange contents of memory with a new value * @v: pointer of type atomic_t * @i: integer value to store in memory * * Atomically sets @v to @i and returns old @v */static inline int atomic_xchg(atomic_t *v, int n){	return xchg(&v->counter, n);} /** * atomic_cmpxchg - atomically exchange contents of memory if it matches * @v: pointer of type atomic_t * @o: old value that memory should have * @n: new value to write to memory if it matches * * Atomically checks if @v holds @o and replaces it with @n if so. * Returns the old value at @v. */static inline int atomic_cmpxchg(atomic_t *v, int o, int n){	return cmpxchg(&v->counter, o, n);} /** * atomic_add_negative - add and test if negative * @v: pointer of type atomic_t * @i: integer value to add * * Atomically adds @i to @v and returns true if the result is * negative, or false when result is greater than or equal to zero. */#define atomic_add_negative(i, v)	(atomic_add_return((i), (v)) < 0) #endif /* __ASSEMBLY__ */ #ifndef __tilegx__#include <asm/atomic_32.h>#else#include <asm/atomic_64.h>#endif #ifndef __ASSEMBLY__ /** * atomic64_xchg - atomically exchange contents of memory with a new value * @v: pointer of type atomic64_t * @i: integer value to store in memory * * Atomically sets @v to @i and returns old @v */static inline long long atomic64_xchg(atomic64_t *v, long long n){	return xchg64(&v->counter, n);} /** * atomic64_cmpxchg - atomically exchange contents of memory if it matches * @v: pointer of type atomic64_t * @o: old value that memory should have * @n: new value to write to memory if it matches * * Atomically checks if @v holds @o and replaces it with @n if so. * Returns the old value at @v. */static inline long long atomic64_cmpxchg(atomic64_t *v, long long o,					long long n){	return cmpxchg64(&v->counter, o, n);} static inline long long atomic64_dec_if_positive(atomic64_t *v){	long long c, old, dec; 	c = atomic64_read(v);	for (;;) {		dec = c - 1;		if (unlikely(dec < 0))			break;		old = atomic64_cmpxchg((v), c, dec);		if (likely(old == c))			break;		c = old;	}	return dec;} #endif /* __ASSEMBLY__ */ #endif /* _ASM_TILE_ATOMIC_H */