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Subject: Re: [PATCH] sched: Support current clocksource handling in
	fallback sched_clock().
From: Daniel Walker <dwalker@fifo99.com>
To: Peter Zijlstra <peterz@infradead.org>
Cc: Paul Mundt <lethal@linux-sh.org>, Thomas Gleixner <tglx@linutronix.de>,
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Date: Thu, 28 May 2009 09:13:38 -0700
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On Thu, 2009-05-28 at 14:59 +0200, Peter Zijlstra wrote:

> 
> 
> CPU0                           CPU1
> 
> clock = ACCESS_ONCE(sched_clocksource);
> 
>                                unload module
>                                  clocksource_unregister()
>                                    sched_clocksource = jiffies
>                                  unmap data/text
> 
> cyc2ns(clock, clocksource_read(clock)) <--- fireworks
> 
> 

Do any module based clocksources even exist right now?
clocksource_unregister only seems to be used 3 times..

Daniel