Re: [PATCH v8 0/8] Don't compute events that won't be used in a metric.

[Andi Kleen]

On 9/17/2021 11:35 PM, Ian Rogers wrote:
>      
> For a metric like:
>    EVENT1 if #smt_on else EVENT2
>      
> currently EVENT1 and EVENT2 will be measured and then when the metric
> is reported EVENT1 or EVENT2 will be printed depending on the value
> from smt_on() during the expr parsing. Computing both events is
> unnecessary and can lead to multiplexing as discussed in this thread:
> https://lore.kernel.org/lkml/20201110100346.2527031-1-irogers@xxxxxxxxxx/
>
> This change modifies expression parsing so that constants are
> considered when building the set of ids (events) and only events not
> contributing to a constant value are measured.


The series looks good to me.


Reviewed-by: Andi Kleen <ak@xxxxxxxxxxxxxxx>


-Andi