On Wed, Dec 27, 2017 at 2:57 AM, gaurav jindal <[email protected]> wrote: > On Wed, Dec 27, 2017 at 01:42:58AM +0100, Rafael J. Wysocki wrote: >> On Tue, Dec 26, 2017 at 8:26 AM, gaurav jindal >> <[email protected]> wrote: >> > When selecting the idle state using cpuidle_select, there is no >> > check on cpuidle_curr_governor. In cpuidle_switch_governor, >> > cpuidle_currr_governor can be set to NULL to specify "disabled". >> >> How exactly? > > In cpuidle_switch_governor: > > /** > * cpuidle_switch_governor - changes the governor > * @gov: the new target governor > * > * NOTE: "gov" can be NULL to specify disabled > * Must be called with cpuidle_lock acquired. > */ > int cpuidle_switch_governor(struct cpuidle_governor *gov) > { > struct cpuidle_device *dev; > > if (gov == cpuidle_curr_governor) > return 0; > > cpuidle_uninstall_idle_handler(); > > if (cpuidle_curr_governor) { > list_for_each_entry(dev, &cpuidle_detected_devices, > device_list) > cpuidle_disable_device(dev); > } > > cpuidle_curr_governor = gov; > > This allows to set the cpuidle_switch_governor as NULL. Although there is no > current code flow leading here, but it has a potential for bug in future. So > may be better to have prevention.
Or maybe not. Why don't you make cpuidle_switch_governor() check the argument against NULL instead?
