[PATCH V5 0/9] perf: Driver specific configuration for PMU

On 22 August 2016 at 09:15, Alexander Shishkin
[off-list ref] wrote:

Mathieu Poirier [off-list ref] writes:

quoted

As such something that used to be a two-step process:

# echo 1 > /sys/bus/coresight/devices/20070000.etr/enable_sink
# perf record -e cs_etm//u --per-thread  uname

is integrated in a single command:

# perf record -e cs_etm/@sink=20070000.etr/u --per-thread  uname

Can't we simply teach perf record to write 1 to that sysfs attribute and
avoid parsing more ascii strings in the kernel? I suspect that would also
take way less code.

That, in my opinion, would be a big hack.  Peter and Jiri, any thoughts on this?

Are there any other use cases for this besides specifying @sink for a
ETM?

Not at this time but there is so many configuration option for the
ETM/PTM tracers (that aren't filters) that I wanted the right
infrastructure to be there should/when we need to expand.

Thanks for taking the time to review this set,
Mathieu

Regards,
--
Alex