Subject: Re: [PATCH] perf_events: Enable idle state tracing for pseries (ppc64)

From: Benjamin Herrenschmidt <[email-masked]>
Date: Fri, 17 Jun 2011 14:24:19 +1000

On Wed, 2011-06-01 at 18:05 +0530, Deepthi Dharwar wrote:
> Hi,
> 
> Please find below a patch, which has perf_events added for pseries (ppc64)
> platform in order to emit the trace required for perf timechart. 
> It essentially enables perf timechart for pseries platfrom to analyse
> power savings events like cpuidle states.

Unless I'm mistaken, you added traces to dedicated CPU idle sleep but
not shared processor. Any reason ?

Also I don't really know that tracing stuff but what's the point of
having start/end _and trace_cpu_idle if you're going to always start &
end around a single occurence of trace_cpu_idle ?

Wouldn't there be a way to start/end and then trace the snooze and
subsequent cede within the same start/end section or that makes no
sense ?

Also would there be any interest in doing the tracing more generically
in idle.c ?

Cheers,
Ben.