On 30/10/2018 09:33, Viresh Kumar wrote: > On 30-10-18, 08:55, Daniel Lezcano wrote: >> The workqueue is called from init_cpu_capacity_callback(). This one is >> called in the notifier callback. IOW the notification callback >> unregisters itself. But if it is not registered, it won't unregister, >> hence it won't call the workqueue and init_cpu_capacity_notifier() is >> not called. > > Sorry, couldn't understand most of your reply :)
Logical, I didn't understand your initial comment :) > Though let me try to explain the problem I was trying to show you.. > > cpufreq-notifier-callback > -> init_cpu_capacity_callback() > -> free raw capacity > -> queue_work() to unregister the notifier > -> return > > ->init_cpu_capacity_callback() called again before work was processed. > -> If we don't check raw_capacity, we may end up using > NULL pointer, as the notifier isn't unregistered yet. Oh, nice catch. I'm wondering if having a statically per_cpu variable, even if it is not free at the end, isn't worth regarding the twisted code we end up with an allocation. -- <http://www.linaro.org/> Linaro.org │ Open source software for ARM SoCs Follow Linaro: <http://www.facebook.com/pages/Linaro> Facebook | <http://twitter.com/#!/linaroorg> Twitter | <http://www.linaro.org/linaro-blog/> Blog
