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Date: Wed, 23 May 2012 00:22:51 +0200 (CEST)
From: Thomas Gleixner <tglx@linutronix.de>
To: Steven Rostedt <rostedt@goodmis.org>
cc: Peter Zijlstra <peterz@infradead.org>,
        Gilad Ben-Yossef <gilad@benyossef.com>,
        Frederic Weisbecker <fweisbec@gmail.com>,
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        Stephen Hemminger <shemminger@vyatta.com>,
        Sven-Thorsten Dietrich <thebigcorporation@gmail.com>,
        Zen Lin <zen@openhuawei.org>
Subject: Re: [RFC][PATCH 00/32] Nohz cpusets v2 (adaptive tickless kernel)
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On Tue, 22 May 2012, Steven Rostedt wrote:

> On Tue, 2012-05-22 at 23:31 +0200, Thomas Gleixner wrote:
> 
> > diff --git a/arch/x86/kernel/tsc.c b/arch/x86/kernel/tsc.c
> > index 590900c..dc8ecc3 100644
> > --- a/arch/x86/kernel/tsc.c
> > +++ b/arch/x86/kernel/tsc.c
> > @@ -109,6 +109,10 @@ static int __init tsc_setup(char *str)
> >  {
> >  	if (!strcmp(str, "reliable"))
> >  		tsc_clocksource_reliable = 1;
> > +	if (!strcmp(str, "perfect")) {
> > +		tsc_clocksource_reliable = 1;
> > +		sched_clock_stable = 1;
> > +	}
> 
> 	else if(!strcmp(str, "pony")) {
> 		tsc_clocksource_reliable = 1;
> 		sched_clock_stable = 1;
> 		tsc_perfect_smp_synchronization = 1;

	else if (!strcmp(str, "real")
	     panic("Can't handle real TSCs!\n");