Re: [PATCH][experimantal] cpufreq: governor: Use an atomic variable for synchronization

Rafael J. Wysocki
2015-12-08T14:00:40Z

On Tuesday, December 08, 2015 07:25:18 PM Viresh Kumar wrote:
> On 08-12-15, 15:19, Rafael J. Wysocki wrote:
> > We know what should be done. We need to wait for the timer function to
> > complete, then cancel the work item spawned by it (if any) and then
> > cancel the timers set by that work item.
>
> Yeah, there is no race, but it looks ugly to me. I have written it
> earlier, and then the spinlock thing looked better to me. :)

It doesn't look nice, but then having a lockless timer function is worth
it in my view.

The code in gov_cancel_work() runs relatively rarely, but the timer
function can run very often, so avoiding the lock in there is a priority
to me.

Plus we can avoid disabling interrupts in two places this way.

Thanks,
Rafael