Re: [PATCH v5 1/3] drivers core: refactor device_shutdown

[Andy Shevchenko]

On Wed, May 16, 2018 at 5:40 AM, Pavel Tatashin
<pasha.tatashin@xxxxxxxxxx> wrote:
> device_shutdown() traverses through the list of devices, and calls
> dev->{bug/driver}->shutdown() for each entry in the list.
>
> Refactor the function by keeping device_shutdown() to do the logic of
> traversing the list of devices, and device_shutdown_one() to perform the
> actual shutdown operation on one device.
>

FWIW,
Reviewed-by: Andy Shevchenko <andy.shevchenko@xxxxxxxxx>

> Signed-off-by: Pavel Tatashin <pasha.tatashin@xxxxxxxxxx>
> ---
>  drivers/base/core.c | 50 +++++++++++++++++++++++++++------------------
>  1 file changed, 30 insertions(+), 20 deletions(-)
>
> diff --git a/drivers/base/core.c b/drivers/base/core.c
> index b610816eb887..ed189f6d1a2f 100644
> --- a/drivers/base/core.c
> +++ b/drivers/base/core.c
> @@ -2765,6 +2765,35 @@ int device_move(struct device *dev, struct device *new_parent,
>  }
>  EXPORT_SYMBOL_GPL(device_move);
>
> +/*
> + * device_shutdown_one - call ->shutdown() for the device passed as
> + * argument.
> + */
> +static void device_shutdown_one(struct device *dev)
> +{
> +       /* Don't allow any more runtime suspends */
> +       pm_runtime_get_noresume(dev);
> +       pm_runtime_barrier(dev);
> +
> +       if (dev->class && dev->class->shutdown_pre) {
> +               if (initcall_debug)
> +                       dev_info(dev, "shutdown_pre\n");
> +               dev->class->shutdown_pre(dev);
> +       }
> +       if (dev->bus && dev->bus->shutdown) {
> +               if (initcall_debug)
> +                       dev_info(dev, "shutdown\n");
> +               dev->bus->shutdown(dev);
> +       } else if (dev->driver && dev->driver->shutdown) {
> +               if (initcall_debug)
> +                       dev_info(dev, "shutdown\n");
> +               dev->driver->shutdown(dev);
> +       }
> +
> +       /* decrement the reference counter */
> +       put_device(dev);
> +}
> +
>  /**
>   * device_shutdown - call ->shutdown() on each device to shutdown.
>   */
> @@ -2801,30 +2830,11 @@ void device_shutdown(void)
>                         device_lock(parent);
>                 device_lock(dev);
>
> -               /* Don't allow any more runtime suspends */
> -               pm_runtime_get_noresume(dev);
> -               pm_runtime_barrier(dev);
> -
> -               if (dev->class && dev->class->shutdown_pre) {
> -                       if (initcall_debug)
> -                               dev_info(dev, "shutdown_pre\n");
> -                       dev->class->shutdown_pre(dev);
> -               }
> -               if (dev->bus && dev->bus->shutdown) {
> -                       if (initcall_debug)
> -                               dev_info(dev, "shutdown\n");
> -                       dev->bus->shutdown(dev);
> -               } else if (dev->driver && dev->driver->shutdown) {
> -                       if (initcall_debug)
> -                               dev_info(dev, "shutdown\n");
> -                       dev->driver->shutdown(dev);
> -               }
> -
> +               device_shutdown_one(dev);
>                 device_unlock(dev);
>                 if (parent)
>                         device_unlock(parent);
>
> -               put_device(dev);
>                 put_device(parent);
>
>                 spin_lock(&devices_kset->list_lock);
> --
> 2.17.0
>



-- 
With Best Regards,
Andy Shevchenko