Re: [PATCH] PM: Add EXPORT macros for exporting PM functions

[Rafael J. Wysocki]

On Mon, Feb 13, 2023 at 4:50 PM Richard Fitzgerald
<rf@xxxxxxxxxxxxxxxxxxxxx> wrote:
>
> On 13/02/2023 15:43, Rafael J. Wysocki wrote:
> > On Mon, Feb 13, 2023 at 2:20 PM Richard Fitzgerald
> > <rf@xxxxxxxxxxxxxxxxxxxxx> wrote:
> >>
> >> Add a set of macros for exporting functions only if CONFIG_PM
> >> is enabled.
> >>
> >> The naming follows the style of the standard EXPORT_SYMBOL_*()
> >> macros that they replace.
> >>
> >> Sometimes a module wants to export PM functions directly to other
> >> drivers, not a complete struct dev_pm_ops. A typical example is
> >> where a core library exports the generic (shared) implementation
> >> and calling code wraps one or more of these in custom code.
> >>
> >> Signed-off-by: Richard Fitzgerald <rf@xxxxxxxxxxxxxxxxxxxxx>
> >> ---
> >>   include/linux/pm.h | 8 ++++++++
> >>   1 file changed, 8 insertions(+)
> >>
> >> diff --git a/include/linux/pm.h b/include/linux/pm.h
> >> index 93cd34f00822..21618f7087f8 100644
> >> --- a/include/linux/pm.h
> >> +++ b/include/linux/pm.h
> >> @@ -379,9 +379,17 @@ const struct dev_pm_ops name = { \
> >>          const struct dev_pm_ops name;                                   \
> >>          __EXPORT_SYMBOL(name, sec, ns);                                 \
> >>          const struct dev_pm_ops name
> >> +#define EXPORT_PM_FN(name)             EXPORT_SYMBOL(name)
> >> +#define EXPORT_PM_FN_GPL(name)         EXPORT_SYMBOL_GPL(name)
> >> +#define EXPORT_PM_FN_NS(name, ns)      EXPORT_SYMBOL_NS(name, ns)
> >> +#define EXPORT_PM_FN_NS_GPL(name, ns)  EXPORT_SYMBOL_NS_GPL(name, ns)
> >
> > Why are the non-GPL variants needed?
> >
>
> I did all four because there are all four variants of EXPORT_DEV_PM_OPS.
> Why are the non-GPL variants of EXPORT_DEV_PM_OPS needed?

They aren't or at least they should not be needed in the mainline.

> I can remove the non-GPL variants of my macros.

Yes, please!

> >>   #else
> >>   #define _EXPORT_DEV_PM_OPS(name, sec, ns)                              \
> >>          static __maybe_unused const struct dev_pm_ops __static_##name
> >> +#define EXPORT_PM_FN(name)
> >> +#define EXPORT_PM_FN_GPL(name)
> >> +#define EXPORT_PM_FN_NS(name, ns)
> >> +#define EXPORT_PM_FN_NS_GPL(name, ns)
> >>   #endif
> >>
> >>   #define EXPORT_DEV_PM_OPS(name) _EXPORT_DEV_PM_OPS(name, "", "")
> >> --
> >> 2.30.2
> >>