Re: [PATCH v2 06/13] asm-generic: Use HAVE_FUNCTION_DESCRIPTORS to define associated stubs

From: Nicholas Piggin
Date: Fri Oct 15 2021 - 07:53:21 EST


Excerpts from Nicholas Piggin's message of October 15, 2021 6:02 pm:
> Excerpts from Christophe Leroy's message of October 15, 2021 4:24 pm:
>>
>>
>> Le 15/10/2021 à 08:16, Nicholas Piggin a écrit :
>>> Excerpts from Christophe Leroy's message of October 14, 2021 3:49 pm:
>>>> Replace HAVE_DEREFERENCE_FUNCTION_DESCRIPTOR by
>>>> HAVE_FUNCTION_DESCRIPTORS and use it instead of
>>>> 'dereference_function_descriptor' macro to know
>>>> whether an arch has function descriptors.
>>>>
>>>> To limit churn in one of the following patches, use
>>>> an #ifdef/#else construct with empty first part
>>>> instead of an #ifndef in asm-generic/sections.h
>>>
>>> Is it worth putting this into Kconfig if you're going to
>>> change it? In any case
>>
>> That was what I wanted to do in the begining but how can I do that in
>> Kconfig ?
>>
>> #ifdef __powerpc64__
>> #if defined(_CALL_ELF) && _CALL_ELF == 2
>> #define PPC64_ELF_ABI_v2
>> #else
>> #define PPC64_ELF_ABI_v1
>> #endif
>> #endif /* __powerpc64__ */
>>
>> #ifdef PPC64_ELF_ABI_v1
>> #define HAVE_DEREFERENCE_FUNCTION_DESCRIPTOR 1
>
> We have ELFv2 ABI / function descriptors iff big-endian so you could
> just select based on that.

Of course that should read ELFv1. To be clearer: BE is ELFv1 ABI and
LE is ELFv2 ABI.

Thanks,
Nick