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1/* SPDX-License-Identifier: GPL-2.0 */2#ifndef _ASM_GENERIC_LOCAL64_H3#define _ASM_GENERIC_LOCAL64_H4 5#include <linux/percpu.h>6#include <asm/types.h>7 8/*9 * A signed long type for operations which are atomic for a single CPU.10 * Usually used in combination with per-cpu variables.11 *12 * This is the default implementation, which uses atomic64_t. Which is13 * rather pointless. The whole point behind local64_t is that some processors14 * can perform atomic adds and subtracts in a manner which is atomic wrt IRQs15 * running on this CPU. local64_t allows exploitation of such capabilities.16 */17 18/* Implement in terms of atomics. */19 20#if BITS_PER_LONG == 6421 22#include <asm/local.h>23 24typedef struct {25 local_t a;26} local64_t;27 28#define LOCAL64_INIT(i) { LOCAL_INIT(i) }29 30#define local64_read(l) local_read(&(l)->a)31#define local64_set(l,i) local_set((&(l)->a),(i))32#define local64_inc(l) local_inc(&(l)->a)33#define local64_dec(l) local_dec(&(l)->a)34#define local64_add(i,l) local_add((i),(&(l)->a))35#define local64_sub(i,l) local_sub((i),(&(l)->a))36 37#define local64_sub_and_test(i, l) local_sub_and_test((i), (&(l)->a))38#define local64_dec_and_test(l) local_dec_and_test(&(l)->a)39#define local64_inc_and_test(l) local_inc_and_test(&(l)->a)40#define local64_add_negative(i, l) local_add_negative((i), (&(l)->a))41#define local64_add_return(i, l) local_add_return((i), (&(l)->a))42#define local64_sub_return(i, l) local_sub_return((i), (&(l)->a))43#define local64_inc_return(l) local_inc_return(&(l)->a)44 45static inline s64 local64_cmpxchg(local64_t *l, s64 old, s64 new)46{47 return local_cmpxchg(&l->a, old, new);48}49 50static inline bool local64_try_cmpxchg(local64_t *l, s64 *old, s64 new)51{52 return local_try_cmpxchg(&l->a, (long *)old, new);53}54 55#define local64_xchg(l, n) local_xchg((&(l)->a), (n))56#define local64_add_unless(l, _a, u) local_add_unless((&(l)->a), (_a), (u))57#define local64_inc_not_zero(l) local_inc_not_zero(&(l)->a)58 59/* Non-atomic variants, ie. preemption disabled and won't be touched60 * in interrupt, etc. Some archs can optimize this case well. */61#define __local64_inc(l) local64_set((l), local64_read(l) + 1)62#define __local64_dec(l) local64_set((l), local64_read(l) - 1)63#define __local64_add(i,l) local64_set((l), local64_read(l) + (i))64#define __local64_sub(i,l) local64_set((l), local64_read(l) - (i))65 66#else /* BITS_PER_LONG != 64 */67 68#include <linux/atomic.h>69 70/* Don't use typedef: don't want them to be mixed with atomic_t's. */71typedef struct {72 atomic64_t a;73} local64_t;74 75#define LOCAL64_INIT(i) { ATOMIC_LONG_INIT(i) }76 77#define local64_read(l) atomic64_read(&(l)->a)78#define local64_set(l,i) atomic64_set((&(l)->a),(i))79#define local64_inc(l) atomic64_inc(&(l)->a)80#define local64_dec(l) atomic64_dec(&(l)->a)81#define local64_add(i,l) atomic64_add((i),(&(l)->a))82#define local64_sub(i,l) atomic64_sub((i),(&(l)->a))83 84#define local64_sub_and_test(i, l) atomic64_sub_and_test((i), (&(l)->a))85#define local64_dec_and_test(l) atomic64_dec_and_test(&(l)->a)86#define local64_inc_and_test(l) atomic64_inc_and_test(&(l)->a)87#define local64_add_negative(i, l) atomic64_add_negative((i), (&(l)->a))88#define local64_add_return(i, l) atomic64_add_return((i), (&(l)->a))89#define local64_sub_return(i, l) atomic64_sub_return((i), (&(l)->a))90#define local64_inc_return(l) atomic64_inc_return(&(l)->a)91 92#define local64_cmpxchg(l, o, n) atomic64_cmpxchg((&(l)->a), (o), (n))93#define local64_try_cmpxchg(l, po, n) atomic64_try_cmpxchg((&(l)->a), (po), (n))94#define local64_xchg(l, n) atomic64_xchg((&(l)->a), (n))95#define local64_add_unless(l, _a, u) atomic64_add_unless((&(l)->a), (_a), (u))96#define local64_inc_not_zero(l) atomic64_inc_not_zero(&(l)->a)97 98/* Non-atomic variants, ie. preemption disabled and won't be touched99 * in interrupt, etc. Some archs can optimize this case well. */100#define __local64_inc(l) local64_set((l), local64_read(l) + 1)101#define __local64_dec(l) local64_set((l), local64_read(l) - 1)102#define __local64_add(i,l) local64_set((l), local64_read(l) + (i))103#define __local64_sub(i,l) local64_set((l), local64_read(l) - (i))104 105#endif /* BITS_PER_LONG != 64 */106 107#endif /* _ASM_GENERIC_LOCAL64_H */108