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#include <arch/types.h>
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#include <arch/types.h>
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typedef struct { volatile __u64 count; } atomic_t;
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typedef struct { volatile __u64 count; } atomic_t;
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/** Atomic add operation.
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/*
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 *
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 * TODO: these are just placeholders for real implementations of atomic_inc and atomic_dec.
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 * Use atomic compare and swap operation to atomically add signed value.
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 *
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 * @param val Atomic variable.
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 * @param i Signed value to be added.
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 *
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 * WARNING: the following functions cause the code to be preemption-unsafe !!!
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 * @return Value of the atomic variable as it existed before addition.
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 */
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 */
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static inline count_t atomic_add(atomic_t *val, int i)
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{
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    __u64 a, b;
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    volatile __u64 x = (__u64) &val->count;
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    __asm__ volatile (
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        "0:\n"
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        "ldx %0, %1\n"
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        "add %1, %3, %2\n"
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        "casx %0, %1, %2\n"
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        "cmp %1, %2\n"
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        "bne 0b\n"
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        "nop\n"
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        : "=m" (*((__u64 *)x)), "=r" (a), "=r" (b)
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        : "r" (i)
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    );
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    return a;
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}
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static inline void atomic_inc(atomic_t *val)
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static inline void atomic_inc(atomic_t *val)
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{
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{
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    val->count++;
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    (void) atomic_add(val, 1);
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}
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}
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static inline void atomic_dec(atomic_t *val)
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static inline void atomic_dec(atomic_t *val)
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{
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{
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    val->count--;
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    (void) atomic_add(val, -1);
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}
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}
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static inline void atomic_set(atomic_t *val, __u64 i)
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static inline void atomic_set(atomic_t *val, __u64 i)
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{
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{
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    val->count = i;
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    val->count = i;