Re: [PATCH 02/10] cpufreq: conservative: Avoid races with transition notifier

[Viresh Kumar <viresh.kumar@linaro.org>]

On 24-06-15, 06:41, Viresh Kumar wrote:
> On 23-06-15, 21:23, Preeti U Murthy wrote:
> > On 06/22/2015 01:32 PM, Viresh Kumar wrote:
> > > It is possible that cpufreq transition notifier is called while the
> > > governor is performing its EXIT operation. If this happens, 'ccdbs'
> > 
> > When does this happen ? As far as I can see, cpufreq transition notifier
> > gets called from the cpufreq kworker or when we set the cpufreq limits.
> 
> Which kworker are you talking about here ? The work-handlers of
> ondemand/conservative governors ?
> 
> Conservative governor has registered for transition notifier and that
> will be called every time frequency of a CPU is updated. And that has
> nothing to do with the governor callbacks. These notifiers are called
> from the ->target() routines of the drivers.
> 
> > And from your previous patches, an exit operation only proceeds after
> > ensuring that no kworker is running (check on ccdbs->policy). And LIMIT
> > operation does not run in parallel too.

Hmm, you were right. I Nack my own patch. :)

-- 
viresh