From mboxrd@z Thu Jan  1 00:00:00 1970
From: tglx@linutronix.de (Thomas Gleixner)
Date: Fri, 22 Apr 2011 18:14:04 +0200 (CEST)
Subject: [PATCH RFC] clk: add support for automatic parent handling
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To: linux-arm-kernel@lists.infradead.org
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On Fri, 22 Apr 2011, Thomas Gleixner wrote:
> On Thu, 21 Apr 2011, Colin Cross wrote:
> 
> Yes, and that's exaclty what we don't want to have. You still need a
> global lock for doing the full tree acquisition and the only advantage
> which is left is that you can do parallel prepare/unprepare and
> everything else (parent settings, rate propagations) will need to do
> the locking dance.

And worse with the prepare/unprepare separation you need to do the
lock dance twice in some cases. Once for the mutex and once for the
spinlock. Not really a intriguing idea.

Thanks,

	tglx