Re: [PATCH v2 3/7] pmdomain: core: Use dev_name() instead of kobject_get_path() in debugfs

Ulf Hansson
2024-08-20T08:58:21Z

On Tue, 20 Aug 2024 at 10:55, Geert Uytterhoeven <geert@linux-m68k.org> wrote:
>
> Hi Ulf,
>
> On Mon, May 27, 2024 at 4:27 PM Ulf Hansson <ulf.hansson@linaro.org> wrote:
> > Using kobject_get_path() means a dynamic memory allocation gets done, which
> > doesn't work on a PREEMPT_RT based configuration while holding genpd's raw
> > spinlock.
> >
> > To fix the problem, let's convert into using the simpler dev_name(). This
> > means the information about the path doesn't get presented in debugfs, but
> > hopefully this shouldn't be an issue.
> >
> > Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
> > ---
> > Changes in v2:
> > - New patch.
>
> Thanks for your patch, which is now commit 9094e53ff5c86ebe ("pmdomain:
> core: Use dev_name() instead of kobject_get_path() in debugfs")
> in pmdomain/next.
>
> > --- a/drivers/pmdomain/core.c
> > +++ b/drivers/pmdomain/core.c
> > @@ -3215,16 +3214,9 @@ static int genpd_summary_one(struct seq_file *s,
> > }
> >
> > list_for_each_entry(pm_data, &genpd->dev_list, list_node) {
> > - kobj_path = kobject_get_path(&pm_data->dev->kobj,
> > - genpd_is_irq_safe(genpd) ?
> > - GFP_ATOMIC : GFP_KERNEL);
> > - if (kobj_path == NULL)
> > - continue;
> > -
> > - seq_printf(s, "\n %-50s ", kobj_path);
> > + seq_printf(s, "\n %-50s ", dev_name(pm_data->dev));
>
> While some of the old names didn't even fit in 50 characters, the new
> names need much less space, so perhaps this is a good opportunity to
> decrease the table width?

Sure, it seems reasonable! Do you want to send a patch?

>
> > rtpm_status_str(s, pm_data->dev);
> > perf_status_str(s, pm_data->dev);
> > - kfree(kobj_path);
> > }
> >
> > seq_puts(s, "\n");

Kind regards
Uffe