Re: [PATCH 1/3] lockref: add a __cond_lock annotation for lockref_put_or_lock

Christoph Hellwig
2025-11-18T05:58:54Z

On Fri, Nov 14, 2025 at 10:18:24AM -0800, Linus Torvalds wrote:
> Macro expansion isn't recursive, and having
>
> #define a(x) something-something a(x)
>
> is actually perfectly fine, and something we do intentionally for
> other reasons (typically because it also allows us to then use "#ifdef
> a" to check whether there is some architecture-specific implementation
> of 'a()')
>
> And yes, you do need that "#undef" to then not get crazy parse errors
> in the actual definition and export of the function, but it would
> allow us to avoid yet another "underscore version of the function".
>
> I dunno. Not a big deal, but it seems annoying to make up a new name
> for this.

I know you can redefine names using macros, and now that you remind
me I remember that you like that. I personally hate it as it means
there are two things with the same name, which makes understanding
the code much harder and confuses tools like cscope. But I can
switch to that approach if you prefer.