Re: [PATCH] perf, x86: try to handle unknown nmis with running perfctrs

Cyrill Gorcunov
2010-08-10T16:16:37Z

On Tue, Aug 10, 2010 at 09:42:00AM +0200, Robert Richter wrote:
> On 09.08.10 16:02:45, Cyrill Gorcunov wrote:
>
> > > @@ -1222,14 +1245,12 @@ perf_event_nmi_handler(struct notifier_block *self,
> > > regs = args->regs;
> > >
> > > apic_write(APIC_LVTPC, APIC_DM_NMI);
> >
> > If only I'm not missing something this apic_write should go up to
> > "case DIE_NMIUNKNOWN" site, no?
>
> This seems to be code from the non-nmi implementation and can be
> removed at all, which should be a separate patch. The vector is
> already set up.
>
> -Robert
>

No, this is just a short way to unmask LVTPC (which is required for
cpus). Actually lookig into this snippet I found that in p4 pmu
I've made one redundant unmaksing operation. will update as only
this area settle down.

-- Cyrill