Re: [PATCH v8 4/8] PM / EM: add support for other devices than CPUs in Energy Model

On 27/05/2020 11:58, Lukasz Luba wrote:

Add support for other devices than CPUs. The registration function does not require a valid cpumask pointer and is ready to handle new devices. Some of the internal structures has been reorganized in order to keep consistent view (like removing per_cpu pd pointers).

Signed-off-by: Lukasz Luba lukasz.luba@arm.com

[ ... ]

} EXPORT_SYMBOL_GPL(em_register_perf_domain);

+/**

• • em_dev_unregister_perf_domain() - Unregister Energy Model (EM) for a device
• • @dev : Device for which the EM is registered
• • Try to unregister the EM for the specified device (but not a CPU).
• */

+void em_dev_unregister_perf_domain(struct device *dev) +{

• if (IS_ERR_OR_NULL(dev) || !dev->em_pd)

• return;
  

• if (_is_cpu_device(dev))

• return;
  

• mutex_lock(&em_pd_mutex);

Is the mutex really needed?

If this function is called that means there is no more user of the em_pd, no?

• em_debug_remove_pd(dev);
• kfree(dev->em_pd->table);
• kfree(dev->em_pd);
• dev->em_pd = NULL;
• mutex_unlock(&em_pd_mutex);

+} +EXPORT_SYMBOL_GPL(em_dev_unregister_perf_domain);