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/* SPDX-License-Identifier: GPL-2.0-only */
#ifndef LINUX_ATOMIC_H_
#define LINUX_ATOMIC_H_
#include <asm-generic/atomic.h>
#include <linux/compiler.h>
#include <asm-generic/cmpxchg.h>
#define raw_cmpxchg_relaxed cmpxchg
/**
* raw_atomic_cmpxchg_relaxed() - atomic compare and exchange with relaxed ordering
* @v: pointer to atomic_t
* @old: int value to compare with
* @new: int value to assign
*
* If (@v == @old), atomically updates @v to @new with relaxed ordering.
*
* Safe to use in noinstr code; prefer atomic_cmpxchg_relaxed() elsewhere.
*
* Return: The original value of @v.
*/
static __always_inline int
raw_atomic_cmpxchg_relaxed(atomic_t *v, int old, int new)
{
return raw_cmpxchg_relaxed(&v->counter, old, new);
}
/**
* atomic_try_cmpxchg_relaxed() - atomic compare and exchange with relaxed ordering
* @v: pointer to atomic_t
* @old: pointer to int value to compare with
* @new: int value to assign
*
* If (@v == @old), atomically updates @v to @new with relaxed ordering.
* Otherwise, updates @old to the current value of @v.
*
* Return: @true if the exchange occured, @false otherwise.
*/
static __always_inline bool
atomic_try_cmpxchg_relaxed(atomic_t *v, int *old, int new)
{
int r, o = *old;
r = raw_atomic_cmpxchg_relaxed(v, o, new);
if (unlikely(r != o))
*old = r;
return likely(r == o);
}
/**
* atomic_fetch_add() - atomic add
* @i: int value to add
* @v: pointer to atomic_t
*
* Atomically updates @v to (@v + @i).
*
* Return: The original value of @v.
*/
static __always_inline int
atomic_fetch_add(int i, atomic_t *v)
{
int old = v->counter;
v->counter += i;
return old;
}
#define atomic_fetch_add_relaxed atomic_fetch_add
#define atomic_fetch_sub(i, v) atomic_fetch_add(-i, v)
#define atomic_fetch_sub_release atomic_fetch_sub
#endif
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