Non core PMU support

Non core PMU support

[Carl E. Love]

Perf users:

I am working on the kernel support for a non CPU PMU.  I believe Intel
calls these uncore PMUs.  Lin Ming posted a patch to add uncore PMU
support last November or so.  It was not accepted.  It is my
understanding the thought on how to name the uncore PMUs was to add the
PMU to the /sys/devices tree.  The user would then give the complete
path to the PMU to identify the PMU.  The user tool would then look up
the PMU type using the specified PMU sysfs path.  The PMU type is then
passed to the kernel to open an event on the specified PMU.  

I don't see any support in the user perf tool for specifying an uncore
PMU.  There is kernel support for multiple PMUs.  

I have not found any recent work on adding uncore PMUs to perf.  Can
anyone tell me what the current approach is to supporting uncore PMUs?
Any pointers on how to add an uncore PMU would be appreciated.

Thanks in advance.

               Carl Love

Re: Non core PMU support

[Arun Sharma]

On Tue, Apr 19, 2011 at 01:47:21PM -0700, Carl E. Love wrote:
> 
> I have not found any recent work on adding uncore PMUs to perf.  Can
> anyone tell me what the current approach is to supporting uncore PMUs?
> Any pointers on how to add an uncore PMU would be appreciated.

If you install libpfm4 + my patch to perf posted here:

http://article.gmane.org/gmane.comp.linux.perfmon2.devel/2912/raw

You'll be able to use the uncore events by name.

 -Arun