Messages in this thread | | | Date | Tue, 9 Jul 2013 10:14:34 +0200 | From | Peter Zijlstra <> | Subject | Re: [PATCH v2 2/2] perf tools: Make Power7 events available for perf |
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On Mon, Jul 08, 2013 at 10:24:34PM -0400, Vince Weaver wrote: > > 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
Right so what I remember of the ARM case is that their /proc/cpuinfo isn't sufficient to identify their PMU. And they don't have a cpuid like instruction at all.
> > 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?
I agree, for x86 cpuid is perfectly fine, as would /proc/cpuinfo be, I suspect that just the model number is sufficient in most cases, even for uncore stuff.
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