[PATCH] perf arm-spe: Use advertised caps/min_interval as default sample_period

[Leo Yan]

On Mon, Feb 21, 2022 at 05:10:42PM +0000, German Gomez wrote:
> When recording SPE traces, the default sample_period is currently being
> set to 1 in the perf_event_attr fields, instead of the value advertised
> in '/sys/devices/arm_spe_0/caps/min_interval':
> 
> Before:
> 
> $ perf record -e arm_spe// -vv -- sleep 1
> [...]
>   { sample_period, sample_freq }   1
> [...]
> 
> Use the value from the above sysfs location as a more sensible default
> (it was already being read, but the value not being used)
> 
> After:
> 
> $ perf record -e arm_spe// -vv -- sleep 1
> [...]
>   { sample_period, sample_freq }   1024
> [...]
> 
> Signed-off-by: German Gomez <german.gomez at arm.com>

The change looks good to me:

Reviewed-by: Leo Yan <leo.yan at linaro.org>