/*
* 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
#ifndef __ASSEMBLY__
#include <linux/compiler.h>
#include <asm/system.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 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_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)
/**
* atomic_inc_not_zero - increment unless the number is zero
* @v: pointer of type atomic_t
*
* Atomically increments @v by 1, so long as @v is non-zero.
* Returns non-zero if @v was non-zero, and zero otherwise.
*/
#define atomic_inc_not_zero(v) atomic_add_unless((v), 1, 0)
/*
* We define xchg() and cmpxchg() in the included headers.
* Note that we do not define __HAVE_ARCH_CMPXCHG, since that would imply
* that cmpxchg() is an efficient operation, which is not particularly true.
*/
/* Nonexistent functions intended to cause link errors. */
extern unsigned long __xchg_called_with_bad_pointer(void);
extern unsigned long __cmpxchg_called_with_bad_pointer(void);
#define tas(ptr) (xchg((ptr), 1))
#endif /* __ASSEMBLY__ */
#ifndef __tilegx__
#include <asm/atomic_32.h>
#else
#include <asm/atomic_64.h>
#endif
/* Provide the appropriate atomic_long_t definitions. */
#ifndef __ASSEMBLY__
#include <asm-generic/atomic-long.h>
#endif
#endif /* _ASM_TILE_ATOMIC_H */
