Re: [dpdk-dev] [PATCH v4 1/1] eal: add 128-bit compare exchange (x86-64 only)

[Thomas Monjalon <thomas@monjalon.net>]

03/04/2019 19:34, Gage Eads:
> This operation can be used for non-blocking algorithms, such as a
> non-blocking stack or ring.
> 
> Signed-off-by: Gage Eads <gage.eads@intel.com>
> Reviewed-by: Honnappa Nagarahalli <honnappa.nagarahalli@arm.com>
> ---
> --- a/lib/librte_eal/common/include/arch/x86/rte_atomic_64.h
> +++ b/lib/librte_eal/common/include/arch/x86/rte_atomic_64.h
> +/**
> + * An atomic compare and set function used by the mutex functions.
> + * (Atomically) Equivalent to:
> + *   if (*dst == *exp)
> + *     *dst = *src
> + *   else
> + *     *exp = *dst
> + *
> + * @note The success and failure arguments must be one of the __ATOMIC_* values
> + * defined in the C++11 standard. For details on their behavior, refer to the
> + * standard.
> + *
> + * @param dst
> + *   The destination into which the value will be written.
> + * @param exp
> + *   Pointer to the expected value. If the operation fails, this memory is
> + *   updated with the actual value.
> + * @param src
> + *   Pointer to the new value.
> + * @param weak
> + *   A value of true allows the comparison to spuriously fail and allows the
> + *   'exp' update to occur non-atomically (i.e. a torn read may occur).
> + *   Implementations may ignore this argument and only implement the strong
> + *   variant.
> + * @param success
> + *   If successful, the operation's memory behavior conforms to this (or a
> + *   stronger) model.
> + * @param failure
> + *   If unsuccessful, the operation's memory behavior conforms to this (or a
> + *   stronger) model. This argument cannot be __ATOMIC_RELEASE,
> + *   __ATOMIC_ACQ_REL, or a stronger model than success.
> + * @return
> + *   Non-zero on success; 0 on failure.
> + */
> +static inline int __rte_experimental
> +rte_atomic128_cmp_exchange(rte_int128_t *dst,
> +			   rte_int128_t *exp,
> +			   const rte_int128_t *src,
> +			   unsigned int weak,
> +			   int success,
> +			   int failure)

I was thinking about keeping the doxygen in the generic file.
Is it possible?