On 9/17/2018 10:58 AM, Xiaoyun Li wrote:
> For IA, the AVX2 vector path is only recommended to be used on later
> platforms (identified by AVX512 support, like SKL etc.) This is because
> performance benchmark shows downgrade when running AVX2 vector path on
> early platform (BDW/HSW) in some cases. But we still observe perf gain
> with some real work loading.
>
> So this patch introduced the new devarg use-latest-supported-vec to
> force the driver always selecting the latest supported vec path. Then
> apps are able to take AVX2 path on early platforms. And this logic can
> be re-used if we will have AVX512 vec path in future.
>
> This patch only affects IA platforms. The selected vec path would be
> like the following:
> Without devarg/devarg = 0:
> Machine vPMD
> AVX512F AVX2
> AVX2 SSE4.2
> SSE4.2 SSE4.2
> <SSE4.2 Not Supported
>
> With devarg = 1
> Machine vPMD
> AVX512F AVX2
> AVX2 AVX2
> SSE4.2 SSE4.2
> <SSE4.2 Not Supported
>
> Other platforms can also apply the same logic if necessary in future.
>
> Signed-off-by: Xiaoyun Li <xiaoyun...@intel.com>
> ---
> v6:
> * Polish the doc and commit log.
> * Use rte_kvargs_process instead of directly kvlist internals.
> v5:
> * Simpify the rx set function.
> v4:
> * Polish the codes.
> v3:
> * Polish the doc and commit log.
> v2:
> * Correct the calling of the wrong function last time.
> * Fix seg fault bug.
Thanks for the update looks good to me.
<...>
> @@ -1078,6 +1078,9 @@ struct i40e_adapter {
> uint64_t pctypes_tbl[I40E_FLOW_TYPE_MAX] __rte_cache_min_aligned;
> uint64_t flow_types_mask;
> uint64_t pctypes_mask;
> +
> + /* For devargs */
> + bool use_latest_vec;
For this one checkpatch is giving following warning:
CHECK:BOOL_MEMBER: Avoid using bool structure members because of possible
alignment issues - see: https://lkml.org/lkml/2017/11/21/384
The comment in the link seems valid. What do you think using a basic storage
type for the variable, like uint8_t?
And overall is there any objection to follow this new convention?
