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Date: Tue, 20 May 2014 07:02:43 +0200
From: Fabian Frederick <fabf@skynet.be>
To: Joe Perches <joe@perches.com>
Cc: Andrew Morton <akpm@linux-foundation.org>,
        linux-kernel <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH V2 mmots] fs/hfsplus/wrapper.c: replace shift loop by
 fls
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On Mon, 19 May 2014 16:50:05 -0700
Joe Perches <joe@perches.com> wrote:

> On Mon, 2014-05-19 at 16:40 -0700, Andrew Morton wrote:
> > On Mon, 19 May 2014 16:22:28 -0700 Joe Perches <joe@perches.com> wrote:
> > 
> > > On Mon, 2014-05-19 at 16:09 -0700, Andrew Morton wrote:
> > > > On Fri, 16 May 2014 22:38:15 +0200 Fabian Frederick <fabf@skynet.be> wrote:
> > > > > Replace while blocksize;shift by fls -1
> > > []
> > > > fls() always makes my brain hurt.  ilog() is nicer?
> > > Maybe take an aspirin?
> > > ilog2(n) is effectively fls(n) - 1
> > Precisely.  ilog2() means "integer log 2".  Whereas fls() is some weird
> > low-level bit-scanning thing.
> 
> <shrug>  find-last[bit]-set is pretty obvious to me.
> ilog2(n) makes me think just a little more.
> 
> > What we want at this callsite is "integer log 2".  So use it.
> 
> Same thing.  Same ratio of use too.
> 
> $ git grep -w fls | wc -l
> 457
> $ git grep -w ilog2 | wc -l
> 391
and the winner is ? :)
> 
>