On Thu, Sep 17, 2020 at 05:31:52PM +0100, Kinsella, Ray wrote:
>
>
> On 09/09/2020 20:30, Honnappa Nagarahalli wrote:
> > <snip>
> >
> >>>
> >> > diff --git a/lib/librte_eal/include/rte_eal.h
> >> b/lib/librte_eal/include/rte_eal.h
> >>>> index ddcf6a2e7a..8148f650f2 100644
> >>>> --- a/lib/librte_eal/include/rte_eal.h
> >>>> +++ b/lib/librte_eal/include/rte_eal.h
> >>>> @@ -43,6 +43,13 @@ enum rte_proc_type_t {
> >>>> RTE_PROC_INVALID
> >>>> };
> >>>>
> >>>> +enum rte_max_simd_t {
> >>> We could add a RTE_MAX_SIMD = 0. Arm platforms can use this to choose
> >> SVE.
> >>>
> >>
> >> Is zero the best value for this? Would setting it to MAX_INT or some other
> >> big
> >> number be better, in terms of comparisons operations, or does that just not
> >> apply at all with SVE?
> > I suggested zero as the bitwidth can be specified from the command line. It
> > would be much easier to input zero vs other number.
>
> Right, but it doesn't end up being that intuitive as interface
> 0 is enabled, 64 is not, 128 is enabled etc ....
>
> Suggest we use a max 16bit integer as 0xFFFF?
>
I can actually see 0 on command-line as being "unlimited", but for the APIs
and internally, I think that it should be converted to a MAX_INT value so
that the comparisons don't need to special-case zero. I agree with
Honnappa, that a -1 or maxint value is awkward on commandline, but
internally it's just an enum, so we can set it to whatever the most
practical value is.
