Re: [PATCH] PM / Domains: add debugfs listing of struct generic_pm_domain-s

From: Maciej Matraszek
Date: Wed Sep 10 2014 - 11:38:23 EST


Hi Greg,
thanks for your reply!

> > +static int __init pm_genpd_debug_init(void)
> > +{
> > + struct dentry *d;
> > +
> > + pm_genpd_debugfs_dir = debugfs_create_dir("pm_genpd", NULL);
> > +
> > + /* No debugfs */
> > + if (IS_ERR(pm_genpd_debugfs_dir))
> > + return PTR_ERR(pm_genpd_debugfs_dir);
>
> You shouldn't care at all, just do this check:
>
> > + if (!pm_genpd_debugfs_dir)
> > + return -ENOMEM;
>
> And all will be fine, because:
>
> > + d = debugfs_create_file("pm_genpd_summary", S_IRUGO,
> > + pm_genpd_debugfs_dir, NULL, &pm_genpd_summary_fops);
>
> That call will resolve away to nothing if debugfs is not enabled, and it
> doesn't make much sense to do anything with an "error" of no debugfs.

Great! I'll fix this bizarre double check.

>
> > + if (!d)
> > + return -ENOMEM;
> > +
> > + return 0;
> > +}
> > +late_initcall(pm_genpd_debug_init);
> > +#endif /* CONFIG_PM_ADVANCED_DEBUG */
>
> No tear-down of the debugfs files on shutdown?

In drivers/clk/clk.c, there is no tear-down of debugfs files paired
with clk_debug_init(), same with wakeup_sources_debugfs_init() from
drivers/base/power/wakeup.c. On the other hand, some subsystems
perform it. What would you prefer?


>
> thanks,
>
> greg k-h

Thanks,
--
Maciej Matraszek
Samsung R&D Institute Poland
Samsung Electronics

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