Re: [PATCH] FRV: Wire up new syscalls

[Ingo Molnar]

* David Howells <dhowells@xxxxxxxxxx> wrote:

> Ingo Molnar <mingo@xxxxxxx> wrote:
> 
> > It would make sense to wire it up for real as it's really easy: 
> > just set HAVE_PERF_COUNTERS in arch/frv/Kconfig, add an empty 
> > arch/frv/include/asm/perf_counter.h file. (Optional: double 
> > check that tools/perf/ builds and works fine on FRV ;-)
> 
> Are these for hardware performance counters?

No. PMU support is not necessary in the first step, you'll still get 
plenty of features from enabling perfcounters on FRV:

  - hrtimer driven recording/profiling

  - various software counters

  - working perf top / perf stat / perf record / perf report

The tools will all work out of box and there's a transparent 
fall-back path in the tools if the hardware counters are not 
available.

It's much easier to add than basic Oprofile support, and you'll get 
a lot more features in exchange as well ;)

[ There might be unanticipated problems of course - please report to
  us any problems (tools/perf/ does not build cleanly, features dont
  work as expected, etc.). ]

	Ingo
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