Re: [PATCH 0/6] add generic round_up_pow2() macro

[P]

Andrew Morton wrote:
> Nick Wilson <njw@xxxxxxxx> wrote:
>
> > The first patch adds a generic round_up_pow2() macro to kernel.h. The
> > remaining patches modify a few files to make use of the new macro.
>
>
> We already have ALIGN() and roundup_pow_of_two().

cool. It doesn't handle x={0,1} though.
Maybe we should have:

static inline unsigned long __attribute_const__ 
__roundup_pow_of_two(unsigned long x)
{
        return (1UL << fls(x - 1));
}

static inline unsigned long __attribute_const__ 
roundup_pow_of_two(unsigned long x)
{
        return (unlikely(x<2)?2:__roundup_pow_of_two(x));
}

--
Pádraig Brady - http://www.pixelbeat.org
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