Re: [PATCH V6 0/5] perf: Driver specific configuration for PMU

From: Jiri Olsa
Date: Sun Aug 28 2016 - 10:18:16 EST


On Thu, Aug 25, 2016 at 02:20:40PM -0600, Mathieu Poirier wrote:

SNIP

> perf record -e some_event/@cfg1,@cfg2=config/ ...
>
> The above are all valid configuration and will see the strings 'cfg1'
> and 'cfg2=config' sent to the PMU driver for parsing and interpretation
> using the existing ioctl() mechanism.
>
> The primary customers for this feature are the CoreSight drivers where
> the selection of a sink (where trace data is accumulated) needs to be
> done in a previous, and separated step, from the launching of the perf
> command.
>
> 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/@20070000.etr/u --per-thread uname
>
> Thanks,
> Mathieu
>
> Changes for V6:
> - Using sysFS rather than an ioctl() to communicate command line
> parameters to the CoreSight PMU.

apart from few nits it looks good.. but can't say for patch 2/5 ;-)

Acked-by: Jiri Olsa <jolsa@xxxxxxxxxx>

thanks,
jirka