Re: [PATCH 1/2] linux/kconfig.h: replace IF_ENABLED() with PTR_IF() in <linux/kernel.h>

From: Andy Shevchenko
Date: Fri Apr 09 2021 - 05:24:48 EST


On Fri, Apr 9, 2021 at 12:00 AM Masahiro Yamada <masahiroy@xxxxxxxxxx> wrote:
>
> <linux/kconfig.h> is included from all the kernel-space source files,
> including C, assembly, linker scripts. It is intended to contain minimal

a minimal

> set of macros to evaluate CONFIG options.
>
> IF_ENABLED() is an intruder here because (x ? y : z) is C code, which
> should not be included from assembly files or linker scripts.
>
> Also, <linux/kconfig.h> is no longer self-contained because NULL is
> defined in <linux/stddef.h>.
>
> Move IF_ENABLED() out to <linux/kernel.h> as PTR_IF().
>
> PTR_IF(IS_ENABLED(CONFIG_FOO), ...) is slightly longer than
> IF_ENABLED(CONFIG_FOO, ...), but it is not a big deal because
> sub-systems often define dedicated macros such as of_match_ptr(),
> pm_ptr() etc. for common use-cases.

> include/linux/kernel.h | 2 ++

Why kernel.h? Shouldn't it belong to a particular domain with a
respective header file?

Really what we have in the kernel.h right now is a complete train
wreck of something.
We have to define what exactly is kernel.h for?

Arnd? Others? Shall we start a wider discussion on the topic?

--
With Best Regards,
Andy Shevchenko