Re: [PATCH] init: move THIS_MODULE from <linux/export.h> to <linux/init.h>

[Masahiro Yamada]

On Sun, Nov 26, 2023 at 4:19 PM Masahiro Yamada <masahiroy@xxxxxxxxxx> wrote:
>
> Commit f50169324df4 ("module.h: split out the EXPORT_SYMBOL into
> export.h") appropriately separated EXPORT_SYMBOL into <linux/export.h>
> because modules and EXPORT_SYMBOL are orthogonal; modules are symbol
> consumers, while EXPORT_SYMBOL are used by symbol providers, which
> may not be necessarily a module.
>
> However, that commit also relocated THIS_MODULE. As explained in the
> commit description, the intention was to define THIS_MODULE in a
> lightweight header, but I do not believe <linux/export.h> was the
> suitable location because EXPORT_SYMBOL and THIS_MODULE are unrelated.
>
> Move it to another lightweight header, <linux/init.h>. The reason for
> choosing <linux/init.h> is to make <linux/moduleparam.h> self-contained
> without relying on <linux/linkage.h> incorrectly including
> <linux/export.h>.
>
> With this adjustment, the role of <linux/export.h> becomes clearer as
> it only defines EXPORT_SYMBOL.
>
> Signed-off-by: Masahiro Yamada <masahiroy@xxxxxxxxxx>
> ---


Applied to kbuild.

I did not get any report from the 0day bot so far,
but I hope it will get a little more compile tests
before getting into linux-next.



>
>  include/linux/export.h | 18 ------------------
>  include/linux/init.h   |  7 +++++++
>  2 files changed, 7 insertions(+), 18 deletions(-)
>
> diff --git a/include/linux/export.h b/include/linux/export.h
> index 9911508a9604..0bbd02fd351d 100644
> --- a/include/linux/export.h
> +++ b/include/linux/export.h
> @@ -6,15 +6,6 @@
>  #include <linux/linkage.h>
>  #include <linux/stringify.h>
>
> -/*
> - * Export symbols from the kernel to modules.  Forked from module.h
> - * to reduce the amount of pointless cruft we feed to gcc when only
> - * exporting a simple symbol or two.
> - *
> - * Try not to add #includes here.  It slows compilation and makes kernel
> - * hackers place grumpy comments in header files.
> - */
> -
>  /*
>   * This comment block is used by fixdep. Please do not remove.
>   *
> @@ -23,15 +14,6 @@
>   * side effect of the *.o build rule.
>   */
>
> -#ifndef __ASSEMBLY__
> -#ifdef MODULE
> -extern struct module __this_module;
> -#define THIS_MODULE (&__this_module)
> -#else
> -#define THIS_MODULE ((struct module *)0)
> -#endif
> -#endif /* __ASSEMBLY__ */
> -
>  #ifdef CONFIG_64BIT
>  #define __EXPORT_SYMBOL_REF(sym)                       \
>         .balign 8                               ASM_NL  \
> diff --git a/include/linux/init.h b/include/linux/init.h
> index 01b52c9c7526..3fa3f6241350 100644
> --- a/include/linux/init.h
> +++ b/include/linux/init.h
> @@ -179,6 +179,13 @@ extern void (*late_time_init)(void);
>
>  extern bool initcall_debug;
>
> +#ifdef MODULE
> +extern struct module __this_module;
> +#define THIS_MODULE (&__this_module)
> +#else
> +#define THIS_MODULE ((struct module *)0)
> +#endif
> +
>  #endif
>
>  #ifndef MODULE
> --
> 2.40.1
>


-- 
Best Regards
Masahiro Yamada