From mboxrd@z Thu Jan  1 00:00:00 1970
From: Richard Cochran <richardcochran@gmail.com>
Subject: Re: [PATCH 08/12] ptp: Added a brand new class driver for ptp
 clocks.
Date: Fri, 13 Aug 2010 11:34:38 +0200
Message-ID: <20100813093438.GA18112@riccoc20.at.omicron.at>
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To: Grant Likely <grant.likely@secretlab.ca>
Cc: netdev@vger.kernel.org, devicetree-discuss@lists.ozlabs.org, linuxppc-dev@lists.ozlabs.org, linux-arm-kernel@lists.infradead.org, Krzysztof Halasa <khc@pm.waw.pl>, Thomas Gleixner <tglx@linutronix.de>
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On Tue, Jun 15, 2010 at 01:11:30PM -0600, Grant Likely wrote:
> On Tue, Jun 15, 2010 at 10:09 AM, Richard Cochran
> > +static DEFINE_SPINLOCK(clocks_lock); /* protects 'clocks' */
> 
> Doesn't appear that clocks is manipulated at atomic context.  Mutex instead?
...
> If the spinlock is changed to a mutex that is held for the entire
> function call, then the logic here can be simpler.

Grant,

I am working on another go at this patch series. Stupid question:

The caller of ptp_clock_register(), which takes the clocks_lock, is
always a module_init() function. Is this always a safe context in
which to call mutex_lock?

Thanks,

Richard