Re: [RFC PATCH 0/3]perf/core: extend perf_reg and perf_sample_regs_intr

On Fri, Nov 06, 2015 at 12:57:17PM +0530, Madhavan Srinivasan wrote:

On Thursday 05 November 2015 06:37 PM, Peter Zijlstra wrote:

quoted

On Thu, Nov 05, 2015 at 02:16:15AM +0530, Madhavan Srinivasan wrote:

quoted

Second patch updates struct arch_misc_reg for arch/powerpc with pmu registers
and adds offsetof macro for the same. It extends perf_reg_value()
to use reg idx to decide on struct to return value from.

Why; what's in those regs?

Was out and did not have access to mail, so missed to respond in time.

In current implementation of patch 2, have added 
few pmu control/status and counter registers,
which give additional information about the PMU context
for the sample.

Yes, I saw that, you still haven't answered the question though. What is
in those regs? Why is exposing that information like this the best
option.