Re: [PATCH v3 RESEND 3/6] bitmap: Make bitmap_onto() available to users

From: Andy Shevchenko
Date: Mon Feb 12 2024 - 09:37:45 EST


On Mon, Feb 12, 2024 at 03:20:22PM +0100, Herve Codina wrote:
> On Mon, 12 Feb 2024 16:01:38 +0200
> Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx> wrote:

..

> Agree, the bitmap_onto() code is simpler to understand than its help.
>
> I introduced bitmap_off() to be the "reverse" bitmap_onto() operations
> and I preferred to avoid duplicating function that do the same things.
>
> On my side, I initially didn't use the bitmap_*() functions and did the the
> bits manipulation by hand.
> During the review, it was suggested to use the bitmap_*() family and I followed
> this suggestion.

I also would go this way, the problems I see with the current implementation are:
- being related to NUMA (and as Rasmus once pointed out better to be there);
- unclear naming, esp. proposed bitmap_off();
- the quite hard to understand help text
- atomicity when it's not needed (AFAICT).

> I did tests to be sure that bitmap_onto() and bitmap_off() did
> exactly the same things as my previous code did.

Yuri, what do you think about all this?

--
With Best Regards,
Andy Shevchenko