Re: [PATCH] config: make AVX and AVX512 configurable

[Thomas Monjalon <thomas@monjalon.net>]

27/04/2017 11:18, Wang, Zhihong:
> From: Thomas Monjalon [mailto:thomas@monjalon.net]
> > 27/04/2017 18:34, Zhihong Wang:
> > > Making AVX and AVX512 configurable is useful for performance and power
> > > testing.
> > >
> > > The similar kernel patch at https://patchwork.kernel.org/patch/9618883/.
> > [...]
> > > +#
> > > +# Recognize/ignore the AVX/AVX512 CPU flags for performance/power
> > testing
> > > +#
> > > +CONFIG_RTE_ENABLE_AVX=y
> > > +CONFIG_RTE_ENABLE_AVX512=n
> > 
> > It is disabling AVX512 in default configuration.
> > Please explain this behaviour change.
> 
> Though AVX512 rte_memcpy has been in DPDK for quite a while it's still
> unproven in hardware with rich use cases. Mark it as experimental for
> now, user can enable it for their own testing.
> 
> Will enable it with enough field tests and possible optimization.
> 
> Should I add the explanation in commit log, or comments in the source,
> or both?

Yes please, add the explanation in the commit log and experimental comment
in the config.