Re: [PATCH v12 1/3] lib/bitmap: add bitmap_{read,write}()

From: Alexander Lobakin
Date: Mon Dec 04 2023 - 11:00:08 EST


From: Yury Norov <yury.norov@xxxxxxxxx>
Date: Mon, 4 Dec 2023 06:22:20 -0800

> On Mon, Dec 04, 2023 at 02:28:09PM +0100, Alexander Potapenko wrote:
>> On Thu, Nov 9, 2023 at 4:11 PM Alexander Potapenko <glider@xxxxxxxxxx> wrote:
>>>
>>> From: Syed Nayyar Waris <syednwaris@xxxxxxxxx>
>>>
>>> The two new functions allow reading/writing values of length up to
>>> BITS_PER_LONG bits at arbitrary position in the bitmap.
>>>
>>> The code was taken from "bitops: Introduce the for_each_set_clump macro"
>>> by Syed Nayyar Waris with a number of changes and simplifications:
>>> - instead of using roundup(), which adds an unnecessary dependency
>>> on <linux/math.h>, we calculate space as BITS_PER_LONG-offset;
>>> - indentation is reduced by not using else-clauses (suggested by
>>> checkpatch for bitmap_get_value());
>>> - bitmap_get_value()/bitmap_set_value() are renamed to bitmap_read()
>>> and bitmap_write();
>>> - some redundant computations are omitted.
>>>
>>> Cc: Arnd Bergmann <arnd@xxxxxxxx>
>>> Signed-off-by: Syed Nayyar Waris <syednwaris@xxxxxxxxx>
>>> Signed-off-by: William Breathitt Gray <william.gray@xxxxxxxxxx>
>>> Link: https://lore.kernel.org/lkml/fe12eedf3666f4af5138de0e70b67a07c7f40338.1592224129.git.syednwaris@xxxxxxxxx/
>>> Suggested-by: Yury Norov <yury.norov@xxxxxxxxx>
>>> Co-developed-by: Alexander Potapenko <glider@xxxxxxxxxx>
>>> Signed-off-by: Alexander Potapenko <glider@xxxxxxxxxx>
>>> Reviewed-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
>>
>> Yury, Andy, do you think anything else is needed for this series?
>> If not, whom should we ask to take it?
>
> I probably need to revisit it, but generally it looks OK.
>
> But I can't take new API without having real users. Now that your MTE
> series is delayed, and Alexander's 'ip_tunnel flags' is not moving as
> well, there's non-zero chance to merge dead code.

One of the PFCP developers had a quick vacation, we'll send PFCP with
the ip_tunnel bitmap conversion this week.
I'll tell Jakub he'd need to pull boys' tree :D

>
> If you want it to be merged, I'd advise you to walk through the kernel
> sources and find good cases where bitmap_read() and bitmap_write() can
> be used. Then append this series with such conversions, and I'll be
> able to move it.
>
> Thanks,
> Yury

Thanks,
Olek