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/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _ASM_GENERIC_LOCAL64_H
#define _ASM_GENERIC_LOCAL64_H
#include <linux/percpu.h>
#include <asm/types.h>
/*
* A signed long type for operations which are atomic for a single CPU.
* Usually used in combination with per-cpu variables.
*
* This is the default implementation, which uses atomic64_t. Which is
* rather pointless. The whole point behind local64_t is that some processors
* can perform atomic adds and subtracts in a manner which is atomic wrt IRQs
* running on this CPU. local64_t allows exploitation of such capabilities.
*/
/* Implement in terms of atomics. */
#if BITS_PER_LONG == 64
#include <asm/local.h>
typedef struct {
local_t a;
} local64_t;
#define LOCAL64_INIT(i) { LOCAL_INIT(i) }
#define local64_read(l) local_read(&(l)->a)
#define local64_set(l,i) local_set((&(l)->a),(i))
#define local64_inc(l) local_inc(&(l)->a)
#define local64_dec(l) local_dec(&(l)->a)
#define local64_add(i,l) local_add((i),(&(l)->a))
#define local64_sub(i,l) local_sub((i),(&(l)->a))
#define local64_sub_and_test(i, l) local_sub_and_test((i), (&(l)->a))
#define local64_dec_and_test(l) local_dec_and_test(&(l)->a)
#define local64_inc_and_test(l) local_inc_and_test(&(l)->a)
#define local64_add_negative(i, l) local_add_negative((i), (&(l)->a))
#define local64_add_return(i, l) local_add_return((i), (&(l)->a))
#define local64_sub_return(i, l) local_sub_return((i), (&(l)->a))
#define local64_inc_return(l) local_inc_return(&(l)->a)
#define local64_cmpxchg(l, o, n) local_cmpxchg((&(l)->a), (o), (n))
#define local64_xchg(l, n) local_xchg((&(l)->a), (n))
#define local64_add_unless(l, _a, u) local_add_unless((&(l)->a), (_a), (u))
#define local64_inc_not_zero(l) local_inc_not_zero(&(l)->a)
/* Non-atomic variants, ie. preemption disabled and won't be touched
* in interrupt, etc. Some archs can optimize this case well. */
#define __local64_inc(l) local64_set((l), local64_read(l) + 1)
#define __local64_dec(l) local64_set((l), local64_read(l) - 1)
#define __local64_add(i,l) local64_set((l), local64_read(l) + (i))
#define __local64_sub(i,l) local64_set((l), local64_read(l) - (i))
#else /* BITS_PER_LONG != 64 */
#include <linux/atomic.h>
/* Don't use typedef: don't want them to be mixed with atomic_t's. */
typedef struct {
atomic64_t a;
} local64_t;
#define LOCAL64_INIT(i) { ATOMIC_LONG_INIT(i) }
#define local64_read(l) atomic64_read(&(l)->a)
#define local64_set(l,i) atomic64_set((&(l)->a),(i))
#define local64_inc(l) atomic64_inc(&(l)->a)
#define local64_dec(l) atomic64_dec(&(l)->a)
#define local64_add(i,l) atomic64_add((i),(&(l)->a))
#define local64_sub(i,l) atomic64_sub((i),(&(l)->a))
#define local64_sub_and_test(i, l) atomic64_sub_and_test((i), (&(l)->a))
#define local64_dec_and_test(l) atomic64_dec_and_test(&(l)->a)
#define local64_inc_and_test(l) atomic64_inc_and_test(&(l)->a)
#define local64_add_negative(i, l) atomic64_add_negative((i), (&(l)->a))
#define local64_add_return(i, l) atomic64_add_return((i), (&(l)->a))
#define local64_sub_return(i, l) atomic64_sub_return((i), (&(l)->a))
#define local64_inc_return(l) atomic64_inc_return(&(l)->a)
#define local64_cmpxchg(l, o, n) atomic64_cmpxchg((&(l)->a), (o), (n))
#define local64_xchg(l, n) atomic64_xchg((&(l)->a), (n))
#define local64_add_unless(l, _a, u) atomic64_add_unless((&(l)->a), (_a), (u))
#define local64_inc_not_zero(l) atomic64_inc_not_zero(&(l)->a)
/* Non-atomic variants, ie. preemption disabled and won't be touched
* in interrupt, etc. Some archs can optimize this case well. */
#define __local64_inc(l) local64_set((l), local64_read(l) + 1)
#define __local64_dec(l) local64_set((l), local64_read(l) - 1)
#define __local64_add(i,l) local64_set((l), local64_read(l) + (i))
#define __local64_sub(i,l) local64_set((l), local64_read(l) - (i))
#endif /* BITS_PER_LONG != 64 */
#endif /* _ASM_GENERIC_LOCAL64_H */
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