Re: [PATCH -v3] perf, x86: try to handle unknown nmis with running perfctrs

Cyrill Gorcunov
2010-08-24T17:20:27Z

On Tue, Aug 24, 2010 at 07:09:36PM +0200, Robert Richter wrote:
> On 24.08.10 12:22:52, Cyrill Gorcunov wrote:
> > Btw, guys, I fail to see how new nmi_watchdog work, we have
> > default_do_nmi
> > if (!(reason & 0xc0)) {
> > if (notify_die(DIE_NMI, "nmi", regs, reason, 2, SIGINT) == == NOTIFY_STOP)
> > return
> > if (nmi_watchdog_tick(regs, reason))
> > return
> >
> > but perf_event_nmi_handler returns NOTIFY_STOP when watchdog is perf event
> > and nmi_watchdog_tick _never_ called, or (most probably) I miss something?
>
> The watchdog is disabled during profiling (perf and oprofile) by
> calling disable_lapic_nmi_watchdog().
>
> -Robert
>

Huh? iirc Don have switched nmi watchdog to native perf subsystem, ie watchdog
uses PERF_COUNT_HW_CPU_CYCLES event, letme check...

-- Cyrill