Re: NMI watchdog question.

John Levon (levon@movementarian.org)
Wed, 6 Nov 2002 18:12:42 +0000


On Wed, Nov 06, 2002 at 09:59:41AM -0800, george anzinger wrote:

> So then the NMI checks for timer interrupts being serviced
> in this case? But, still, why the turn off if the timer
> does not go thru the APIC? The case this came up in is an
> SMP machine, but the test in apic.c shows that the PIT
> interrupt does not go thru the APIC. Leaving NMI on seems
> to work, so I am wondering if this is just old code.

It seems that the test should be :

if (nmi_watchdog == NMI_IO_APIC) {
... disable it
}

I don't think the perfctr watchdog would be affected by the code in
io_apic.c

(on a vaguely related note, booting with nmi_watchdog=2 on my SMP
machine gives high rates of nmis :

janus:~# cat /proc/interrupts | grep NMI ; sleep 1 ; cat /proc/interrupts | grep NMI
NMI: 88358 88358
NMI: 88432 88397

when the machine is compiling kernels. I dunno why ...)

regards
john

-- 
"When a man has nothing to say, the worst thing he can do is to say it
memorably."
	- Calvin Trillin
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