From mboxrd@z Thu Jan  1 00:00:00 1970
From: Luc Van Oostenryck <luc.vanoostenryck@gmail.com>
Subject: Re: sparse problem with Linux kernel v5.5
Date: Fri, 7 Feb 2020 13:43:05 +0100
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To: Uwe =?utf-8?Q?Kleine-K=C3=B6nig?= <uwe@kleine-koenig.org>
Cc: Martin KaFai Lau <kafai@fb.com>, Linus Torvalds <torvalds@linux-foundation.org>, Alexei Starovoitov <ast@kernel.org>, Randy Dunlap <rdunlap@infradead.org>, Linux-Sparse <linux-sparse@vger.kernel.org>, Arthur Fabre <afabre@cloudflare.com>

On Fri, Feb 07, 2020 at 12:34:02PM +0100, Uwe Kleine-König wrote:
> On 2/7/20 9:29 AM, Martin KaFai Lau wrote:
> > I believe x == 1 needs an extra case since ilog2(0) won't work.
> > 
> > Since this function (map creation) is not on the fast path,
> > I currently opt for Linus's suggestion which its code is more
> > self-explanatory.
> 
> If you put my suggestion in a macro that is called for example
> 
> 	ilog2_roundup()
> 
> you might have both: easier code and self-explanation.

This is, essentially, the same as the existing order_base_2().

Best regards,
-- Luc