Re: [PATCH V10 12/15] ptp: Added a brand new class driver for ptpclocks.

From: Richard Cochran
Date: Tue Feb 15 2011 - 12:30:05 EST


On Fri, Feb 11, 2011 at 09:15:24AM +0100, Richard Cochran wrote:
> On Tue, Feb 01, 2011 at 06:00:31PM -0800, John Stultz wrote:
> > So what is serializing access to the timestamp_event_queue here? I don't
> > see any usage of tsevq_mux by the callers. Am I missing it? It looks
> > like its called from interrupt context, so do you really need a spinlock
> > and not a mutex here?
>
> The external timestamp FIFO is written only from interrupt context.

Oops, I lied. After reworking the phyter driver, I find that I want to
enqueue time stamps from non-interrupt contexts, too.

So, you are right. This will need a spin lock...

Thanks,

Richard
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