Re: [PATCH] bitops: simplify generic bit finding functions

Thomas Gleixner
2008-04-28T16:48:37Z

On Mon, 28 Apr 2008, Linus Torvalds wrote:
> >
> > How about making the optimization controlled by a config switch so
> > arch maintainers can decide whether they want to enable the constant
> > optimization or unconditionally call the lib function ?
>
> No.
>
> This is just making that damn header line look worse and worse.
>
> Is there a _reason_ to optimize this stupid function this way?

On architectures which have a find bit instruction we can replace the
call to the library function by a single instruction when the size of
the bitmap is less/equal bits per long and when the bitnr is a
constant.

Thanks,
tglx