Re: [PATCH] power: qos: no need to check return value of debugfs_create functions

From: Rafael J. Wysocki
Date: Tue Jan 22 2019 - 10:30:53 EST


On Tue, Jan 22, 2019 at 4:25 PM Greg Kroah-Hartman
<gregkh@xxxxxxxxxxxxxxxxxxx> wrote:
>
> When calling debugfs functions, there is no need to ever check the
> return value. The function can work or not, but the code logic should
> never do something different based on this.
>
> Cc: "Rafael J. Wysocki" <rjw@xxxxxxxxxxxxx>
> Cc: Len Brown <len.brown@xxxxxxxxx>
> Cc: Pavel Machek <pavel@xxxxxx>
> Cc: linux-pm@xxxxxxxxxxxxxxx
> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

All of these changes are fine by me and I can take the patches
touching the code maintained by me, so please let me know.

> ---
> kernel/power/qos.c | 8 ++------
> 1 file changed, 2 insertions(+), 6 deletions(-)
>
> diff --git a/kernel/power/qos.c b/kernel/power/qos.c
> index b7a82502857a..9d22131afc1e 100644
> --- a/kernel/power/qos.c
> +++ b/kernel/power/qos.c
> @@ -582,10 +582,8 @@ static int register_pm_qos_misc(struct pm_qos_object *qos, struct dentry *d)
> qos->pm_qos_power_miscdev.name = qos->name;
> qos->pm_qos_power_miscdev.fops = &pm_qos_power_fops;
>
> - if (d) {
> - (void)debugfs_create_file(qos->name, S_IRUGO, d,
> - (void *)qos, &pm_qos_debug_fops);
> - }
> + debugfs_create_file(qos->name, S_IRUGO, d, (void *)qos,
> + &pm_qos_debug_fops);
>
> return misc_register(&qos->pm_qos_power_miscdev);
> }
> @@ -685,8 +683,6 @@ static int __init pm_qos_power_init(void)
> BUILD_BUG_ON(ARRAY_SIZE(pm_qos_array) != PM_QOS_NUM_CLASSES);
>
> d = debugfs_create_dir("pm_qos", NULL);
> - if (IS_ERR_OR_NULL(d))
> - d = NULL;
>
> for (i = PM_QOS_CPU_DMA_LATENCY; i < PM_QOS_NUM_CLASSES; i++) {
> ret = register_pm_qos_misc(pm_qos_array[i], d);
> --
> 2.20.1
>