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From:   Yun Levi <ppbuk5246@gmail.com>
Date:   Thu, 3 Dec 2020 03:27:33 +0900
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Subject: 
To:     Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc:     Yury Norov <yury.norov@gmail.com>,
        Rasmus Villemoes <linux@rasmusvillemoes.dk>, dushistov@mail.ru,
        Arnd Bergmann <arnd@arndb.de>,
        Andrew Morton <akpm@linux-foundation.org>,
        "Gustavo A. R. Silva" <gustavo@embeddedor.com>,
        William Breathitt Gray <vilhelm.gray@gmail.com>,
        richard.weiyang@linux.alibaba.com, joseph.qi@linux.alibaba.com,
        skalluru@marvell.com, Josh Poimboeuf <jpoimboe@redhat.com>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        linux-arch@vger.kernel.org
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On Thu, Dec 3, 2020 at 2:36 AM Andy Shevchenko
<andriy.shevchenko@linux.intel.com> wrote:
>
> On Wed, Dec 02, 2020 at 09:26:05AM -0800, Yury Norov wrote:
> > On Wed, Dec 2, 2020 at 3:50 AM Yun Levi <ppbuk5246@gmail.com> wrote:
>
> ...
>
> >  I think this patch has some good catches. We definitely need to implement
> > find_last_zero_bit(), as it is used by fs/ufs, and their local
> > implementation is not optimal.
>
> Side note: speaking of performance, any plans to fix for_each_*_bit*() for
> cases when the nbits is known to be <= BITS_PER_LONG?
>
> Now it makes an awful code generation (something like few hundred bytes of
> code).
>
> --
> With Best Regards,
> Andy Shevchenko
>
>

> Side note: speaking of performance, any plans to fix for_each_*_bit*() for
> cases when the nbits is known to be <= BITS_PER_LONG?

Frankly Speaking, I don't have an idea in now.....
Could you share your idea or wisdom?

Thanks.
Levi.