diff mbox series

init: move THIS_MODULE from <linux/export.h> to <linux/init.h>

Message ID 20231126071914.932241-1-masahiroy@kernel.org (mailing list archive)
State New, archived
Headers show
Series init: move THIS_MODULE from <linux/export.h> to <linux/init.h> | expand

Commit Message

Masahiro Yamada Nov. 26, 2023, 7:19 a.m. UTC
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@kernel.org>
---

 include/linux/export.h | 18 ------------------
 include/linux/init.h   |  7 +++++++
 2 files changed, 7 insertions(+), 18 deletions(-)

Comments

Masahiro Yamada Dec. 3, 2023, 10:06 a.m. UTC | #1
On Sun, Nov 26, 2023 at 4:19 PM Masahiro Yamada <masahiroy@kernel.org> 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@kernel.org>
> ---


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
>
Luis Chamberlain Dec. 5, 2023, 5:54 a.m. UTC | #2
On Sun, Nov 26, 2023 at 04:19:14PM +0900, Masahiro Yamada 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@kernel.org>

Reviewed-by: Luis Chamberlain <mcgrof@kernel.org>

Do you want this this to go through modules-next or your tree? I'm fine
it goes either way.

  Luis
Paul Gortmaker Dec. 6, 2023, 6:56 p.m. UTC | #3
[Re: [PATCH] init: move THIS_MODULE from <linux/export.h> to <linux/init.h>] On 03/12/2023 (Sun 19:06) Masahiro Yamada wrote:

> On Sun, Nov 26, 2023 at 4:19???PM Masahiro Yamada <masahiroy@kernel.org> 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@kernel.org>
> > ---
> 
> 
> 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.

Haven't touched that kind of header shuffle for over 10 years?

But yeah, it is near impossible to not trip over some implicit header
inclusion somewhere in some driver or a less common arch and hence break
the build at least once when doing this kind of stuff.

Paul.
--

> 
> 
> 
> >
> >  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
Masahiro Yamada Dec. 9, 2023, 7:26 p.m. UTC | #4
On Tue, Dec 5, 2023 at 2:54 PM Luis Chamberlain <mcgrof@kernel.org> wrote:
>
> On Sun, Nov 26, 2023 at 04:19:14PM +0900, Masahiro Yamada 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@kernel.org>
>
> Reviewed-by: Luis Chamberlain <mcgrof@kernel.org>


I will fold your reviewed-by tag.

Thanks.


>
> Do you want this this to go through modules-next or your tree? I'm fine
> it goes either way.
>
>   Luis
diff mbox series

Patch

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