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

Geert Uytterhoeven
2024-08-20T08:55:47Z

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?

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

Gr{oetje,eeting}s,

Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds