Re: Perf events/ARM

From: Jamie Iles
Date: Tue Dec 01 2009 - 09:52:01 EST


Pete, Ingo,

On Tue, Dec 01, 2009 at 03:40:44PM +0100, Peter Zijlstra wrote:
> Things like wakeups and ->event_limit might get delayed.
>
> Delayed wakeups can be mitigated by larger buffers, delayed disable on
> ->event_limit is not something you can fix up.
>
> Does your PMU generate regular interrupts or actual NMIs? If its normal
> interrupts you can simply call perf_event_do_pending() at the
> pmu-interrupt tail.
The PMU generates regular interrupts and in the case of the platform I'm
working on these go to a regular vectored interrupt controller all sharing the
same vector. So I'll add a call to perf_event_do_pending() at the tail of the
PMU IRQ and leave set_perf_event_pending() as a nop.

Thanks,

Jamie
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