[PATCH 2/4] powerpc: Introduce asm-prototypes.h

[Christophe Leroy]

On 08/14/2020 01:04 PM, Michael Ellerman wrote:
> Christophe Leroy <christophe.leroy at csgroup.eu> writes:
>> Le 18/05/2016 à 03:16, Daniel Axtens a écrit :
>>> Sparse picked up a number of functions that are implemented in C and
>>> then only referred to in asm code.
>>>
>>> This introduces asm-prototypes.h, which provides a place for
>>> prototypes of these functions.
>>
>> It looks like this is a mis-use of asm-prototypes.h
>>
>> On other architectures, asm-prototypes.h is there to allow MODVERSION to
>> sent versions for exported assembly functions (I checked history of that
>> file in x86 and arm64).
> 
> Look closer :)
> 
> 42f5b4cacd78 ("powerpc: Introduce asm-prototypes.h") (Jun 2016)
> 334bb7738764 ("x86/kbuild: enable modversions for symbols exported from asm") (Dec 2016)
> c3296a1391cb ("arm64: add <asm/asm-prototypes.h>") (Dec 2018)

Aren't you all sitting at the same place in the middle of Pacific Ocean, 
far far away from Paris ? :)

Looking closer I see: mdr: (Ok, that's Nov 2016 but ...)

commit 4efca4ed05cbdfd13ec3e8cb623fb77d6e4ab187
Author: Nicholas Piggin <npiggin at gmail.com>
Date:   Tue Nov 1 12:46:19 2016 +1100

     kbuild: modversions for EXPORT_SYMBOL() for asm

     Allow architectures to create asm/asm-prototypes.h file that
     provides C prototypes for exported asm functions, which enables
     proper CRC versions to be generated for them.

     Signed-off-by: Nicholas Piggin <npiggin at gmail.com>
     Signed-off-by: Michal Marek <mmarek at suse.com>




> 
>> It looks like you have used it on the other way round, you have declared
>> in it C functions used by ASM functions, whereas it is supposed to be
>> dedicated to declaring exported ASM functions used by C functions.
> 
> But yes, it's since been co-opted for the modversions stuff.
> 
> I guess the contents should be split out into appropriate headers
> depending on what the prototypes are for.
> 


Christophe