Messages in this thread | | | Date | Mon, 8 Jul 2013 22:24:34 -0400 (EDT) | From | Vince Weaver <> | Subject | Re: [PATCH v2 2/2] perf tools: Make Power7 events available for perf |
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On Tue, 9 Jul 2013, Michael Ellerman wrote:
> On Thu, Jul 04, 2013 at 02:57:00PM +0200, Peter Zijlstra wrote: > > > > Right; I think Stephane and Jiri are in favour of creating a 'new' project that > > includes just the event definitions in a plain text format and a little library > > with parser to be used by all interested parties. > > OK that would be great. > > The part that seems to be missing to make that work is we have no way of > matching the PMU that appears in /sys with a list of events. > > Eg. on my system I have /sys/bus/event_source/devices/cpu - but there's > nothing in there to identify that it's a Sandy Bridge.
So something like they have on ARM?
vince@pandaboard:/sys/bus/event_source/devices$ ls -l lrwxrwxrwx 1 root root 0 Jul 8 21:57 ARMv7 Cortex-A9 -> ../../../devices/ARMv7 Cortex-A9 lrwxrwxrwx 1 root root 0 Jul 8 21:57 breakpoint -> ../../../devices/breakpoint lrwxrwxrwx 1 root root 0 Jul 8 21:57 software -> ../../../devices/software lrwxrwxrwx 1 root root 0 Jul 8 21:57 tracepoint -> ../../../devices/tracepoint
> For the cpu you can obviously just detect what processor you're on with > cpuid or whatever, but it's a bit of a hack. And that really doesn't > work for non-cpu PMUs.
why is it a hack to use cpuid?
People have done event lists in userspace for years. Why must it be the kernel's job?
Vince Weaver vincent.weaver@maine.edu http://www.eece.maine.edu/~vweaver/
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