[PATCH v2 4/9] clocksource/cadence_ttc: Use enable/disable_irq

[Thomas Gleixner]

On Fri, 6 Dec 2013, Sören Brinkmann wrote:
> On Thu, Nov 28, 2013 at 08:07:10PM +0100, Thomas Gleixner wrote:
> > There is a solution to this. We can identify the broadcast device in
> > the core and serialize all callers including interrupts on a different
> > cpu against the update. So no need for the disable/enable_irq() dance.
> 
> IIUC, and please correct me if I'm wrong, with the patch I'd simply call
> 'clockevents_update_freq() without having to disable IRQs. But I'm not
> sure whether periodic mode is covered. I found, that I had to reprogram
> the timer interval in my clock notifier callback when the timer
> frequency changes. I think 'clockevents_update_freq()' only handles
> oneshot mode. For that reason I call 'ttc_set_interval()' in the clock
> notifier in case the timer is in periodic mode. For that call we'd still
> have possible races. I guess the best solution would be to move that
> functionality into 'clockevents_update_freq()'?

Indeed.