Re: [RFC PATCH 1/1] perf arm64: Implement --topdown with metrics

[Andrew Kilroy]

On 15/12/2021 12:53, John Garry wrote:
> > > In addition we could also add a --topdown arg to force using JSON 
> > > metricgroups.
> >
> > What arg do think would be supplied?
>
> something like -json or -metricgroup, meaning "Use pmu-events metric 
> events to calculate topdown results rather than kernel CPU PMU events. 
> This is default fallback if the kernel CPU PMU does not support topdown 
> events"

John,

Andi requested that the json metrics be disabled on x86 in


https://lore.kernel.org/linux-perf-users/12e0deef-08db-445f-4958-bcd5c3e10367@xxxxxxxxxxxxxxx/#t

If we do that, do you still think the --topdown=<arg>  modification is 
needed?  I guess it would have to report an error if someone requests 
--topdown=json-metrics on x86.

Thanks,
Andrew