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Date: Tue, 5 Jul 2011 13:20:02 +0200
From: Ingo Molnar <mingo@elte.hu>
To: Cyrill Gorcunov <gorcunov@gmail.com>
Cc: Don Zickus <dzickus@redhat.com>, Stephane Eranian <eranian@google.com>,
        Lin Ming <ming.m.lin@intel.com>,
        Peter Zijlstra <a.p.zijlstra@chello.nl>,
        Arnaldo Carvalho de Melo <acme@redhat.com>,
        Frederic Weisbecker <fweisbec@gmail.com>,
        LKML <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH -tip, final] perf, x86: Add hw_watchdog_set_attr() in a
 sake of nmi-watchdog on P4
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* Cyrill Gorcunov <gorcunov@gmail.com> wrote:

> On Tue, Jul 05, 2011 at 12:59:59PM +0200, Ingo Molnar wrote:
> ...
> > 
> > are 'non-sleeping ticks' non-halted cycles - i.e. cycles that 
> > always count with CPU frequency and can thus be used for periodic 
> > frequencies?
> 
> Yes, I think so (btw, as far as I remember oprofile does the same 
> 'threshold' gaming for nmi-watchdog).

But the NMI watchdog does not need a constant frequency event - it 
can use unhalted cycles just fine. Why does it need unhalted cycles 
on P4?

Thanks,

	Ingo