Re: [PATCH v1 1/1] ACPI: bus: Introduce acpi_dev_get() and reuse it in ACPI code

From: Andy Shevchenko
Date: Mon Apr 12 2021 - 13:48:11 EST


On Mon, Apr 12, 2021 at 8:32 PM Rafael J. Wysocki <rafael@xxxxxxxxxx> wrote:
> On Sat, Apr 10, 2021 at 3:47 PM Andy Shevchenko
> <andy.shevchenko@xxxxxxxxx> wrote:

...

> > static void get_acpi_device(void *dev)
> > {
> > - if (dev)
> > - get_device(&((struct acpi_device *)dev)->dev);
> > + acpi_dev_get(dev);
>
> I would do
>
> if (dev)
> acpi_dev_get(dev);
>
> here.

Hmm... I don't see a point. acpi_dev_get() guaranteed to perform this check.

> > }


> > +static inline void acpi_dev_get(struct acpi_device *adev)
> > +{
> > + if (adev)
> > + get_device(&adev->dev);
>
> And I would drop the adev check from here (because the code calling it
> may be running with wrong assumptions if adev is NULL). Or it should
> return adev and the caller should be held responsible for checking it
> against NULL (if they care).

But this follows the get_device() / put_device() logic. Personally I
don't think this is a good idea to deviate. Note the
acpi_bus_get_acpi_device() / acpi_bus_put_acpi_device() as well.

> > +}



--
With Best Regards,
Andy Shevchenko