Re: [PATCH v3 1/3] rust: print: Add do_once_lite macro

[jens.korinth@tuta.io]

> In addition, the intra-doc link does not really work in commit
> messages :) You probably want to either remove the link, or use an
> actual Link: tag, e.g.
>
> ...to replace `do_once_lite_if` [0] in...
> ...
> Link: https://... [0]
>
Yes, you're right, I also just noticed that the C macro is of course called
`DO_ONCE_LITE_IF`. Will fix this and the rustdoc issues in the next
revision.

> Since we will have `pr_warn_once!` for this, could we perhaps come up
> with another example? i.e. to avoid users thinking that they should
> use it this way.
>
> Also, you could use `assert*!` (possibly hidden, depending on what you
> want the user to see) since it doubles as a test.
>
There aren't many other uses of `DO_ONCE_LITE_IF` in the kernel, that's
why I kept it in `print.rs` and hidden. I didn't quite understand what you
meant with `assert*!` - can you give me an example?

>> +#[doc(hidden)]
>>
>
> Do we want it to be hidden? I guess this could be useful for other
> abstractions etc.
>
> In addition, if we unhide it, should we move it into its own file?
> Just like C has `once_lite.h` etc.
>
Good point, but I'd only do that if it has at least one other use from
somewhere else. I was considering to implement `WARN_*_ONCE`, the
C implementations also use `DO_ONCE_LITE_IF`? But as far as I can tellthere is no implementation of `WARN`, or `__WARN_printf` yet and that
won't be trivial.
Jens