Re: [RFC] para virt interface of perf to support kvm guest os statisticscollection in guest os

From: Avi Kivity
Date: Wed Jun 09 2010 - 07:13:15 EST

On 06/09/2010 01:08 PM, Peter Zijlstra wrote:
On Wed, 2010-06-09 at 12:41 +0300, Avi Kivity wrote:
Disabling the watchdog is unfortunate. Why is it necessary?

perf always uses NMI, so we disable the nmi_watchdog when a perf_event is
set up in case they might have impact.

Ok. Is that the case for the hardware pmus as well? If so it might be
done in common code.
The x86 hardware pmu implementation disables the lapic watchdog too, but
recent kernels come with a watchdog implementation on top of perf, the
old lapic one will be depricated.

So this should indeed be in common code, and removed (for all pmus) when the new watchdog is merged in 2.6.36.

error compiling committee.c: too many arguments to function

To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at
Please read the FAQ at