Messages in this thread | | | Subject | Re: [PATCH 3/3] alpha: Implement HW performance events on the EV67 and later CPUs. | From | Peter Zijlstra <> | Date | Tue, 04 May 2010 09:40:08 +0200 |
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On Sat, 2010-05-01 at 11:55 +1200, Michael Cree wrote: > +/* I wonder what this is for ??? */ > +void set_perf_event_pending(void) > +{ > +}
If the PMU Interrupt comes in as an NMI we cannot take locks and such from its handler. So what we do is queue that work to be ran later. The kernel has a fallback to run this stuff from the timer hardirq, but if the PMI is IRQ context (like ARM) you can simply call perf_event_do_pending() at its tail.
Alternatively you can self-IPI like x86 does and run perf_event_do_pending() from there.
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