Messages in this thread | | | Date | Tue, 9 Jul 2013 11:05:30 -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, Peter Zijlstra wrote:
> 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.
libpfm4 uses the CPU part : 0xc09 line in /proc/cpuinfo on ARM, and that's enough for the processors PAPI supports (Cortex A8/A9/A15 plus the 1176 on the raspberry-pi). I'm guessing it wouldn't be enough if we wanted to support *all* ARMs with PMUs.
And speaking of ARM, I should be railing at them for breaking the ABI too, with their (understandable yet still ABI breaking) decision to remove BogoMIPS from /proc/cpuinfo. That change will impact PAPI as well as various other programs I maintain that have the misfortune of parsing that file.
Vince
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