Re: [PATCH v4 06/18] PM: EM: Check if the get_cost() callback is present in em_compute_costs()

[Lukasz Luba]

On 9/26/23 19:46, Rafael J. Wysocki wrote:
> On Mon, Sep 25, 2023 at 10:11 AM Lukasz Luba <lukasz.luba@xxxxxxx> wrote:
> > The em_compute_cost() is going to be re-used in runtime modified EM
> > code path. Thus, make sure that this common code is safe and won't
> > try to use the NULL pointer. The former em_compute_cost() didn't have to
> > care about runtime modification code path. The upcoming changes introduce
> > such option, but with different callback. Those two paths which use
> > get_cost() (during first EM registration) or update_power() (during
> > runtime modification) need to be safely handled in em_compute_costs().
>
> I would just say something like this:
>
> "Subsequent changes will introduce a case in which cb->get_cost may
> not be set in em_compute_costs(), so add a check to ensure that it is
> not NULL before attempting to dereference it."
>
> The rest of the changelog is just redundant IMO.

Make sense, thanks, I'll change that.