Re: [RFC] linkage: new macros for functions and data

From: Ingo Molnar
Date: Thu Mar 16 2017 - 04:04:18 EST



* Jiri Slaby <jslaby@xxxxxxx> wrote:

> SYM_LOCAL_ALIAS_START -- use where there are two local names for one code
> SYM_ALIAS_START -- use where there are two global names for one code
> SYM_LOCAL_FUNC_START -- use for local functions
> SYM_FUNCTION_START -- use for global functions
> SYM_WEAK_FUNC_START -- use for weak functions
> SYM_ALIAS_END -- the end of LOCALALIASed or ALIASed code
> SYM_FUNCTION_END -- the end of SYM_LOCAL_FUNC_START, SYM_FUNCTION_START, SYM_WEAK_FUNC_START, ...
> SYM_DATA_START -- global data symbol
> SYM_DATA_END -- the end of SYM_DATA_START symbol

This looks mostly good to me, with minor details:

- The mixed 'FUNC' and 'FUNCTION' naming looks a bit confusing - I'd pick one and
use that consistently.

- I'd also make the START/END constructs look more symmetric, i.e. make the
attribute a postfix, not a prefix.

- In fact I'd make the 'alias' notion an attribute as well - what matters mostly
is that it's a function symbol, and that fact is lost from the SYM_ALIAS naming.

I.e. something like this:

SYM_FUNCTION_START
SYM_FUNCTION_START_WEAK
SYM_FUNCTION_START_LOCAL
SYM_FUNCTION_START_ALIAS
SYM_FUNCTION_START_LOCAL_ALIAS
...
SYM_FUNCTION_END

SYM_DATA_START
SYM_DATA_END

Note how simple and structured looking the nomenclature is when grouped in such a
way, how easy it is to verify at a glance, and how easy it is to extend with new
postfixes.

( In theory we could also make the attributes a real macro argument in the future,
should the number of attributes increase significantly. )

Does this look good to everyone?

Thanks,

Ingo