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        Ben Skeggs <bskeggs@redhat.com>,
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        Andrew Morton <akpm@linux-foundation.org>
Subject: Re: [RFC][PATCH] kernel.h: Add generic roundup_64() macro
To:     Steven Rostedt <rostedt@goodmis.org>,
        Linus Torvalds <torvalds@linux-foundation.org>
References: <20190523100013.52a8d2a6@gandalf.local.home>
 <CAHk-=wg5HqJ2Kfgpub+tCWQ2_FiFwEW9H1Rm+an-BLGaGvDDXw@mail.gmail.com>
 <20190523112740.7167aba4@gandalf.local.home>
From:   Roger Willcocks <roger@filmlight.ltd.uk>
Message-ID: <e4e875f0-2aa5-89f4-f462-78bedb9c5cde@filmlight.ltd.uk>
Date:   Fri, 24 May 2019 16:11:14 +0100
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On 23/05/2019 16:27, Steven Rostedt wrote:
>
> I haven't yet tested this, but what about something like the following:
>
> ...perhaps forget about the constant check, and just force
> the power of two check:
>
> 							\
> 	if (!(__y & (__y >> 1))) {			\
> 		__x =3D round_up(x, y);			\
> 	} else {					\

You probably want

 =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 if (!(__y &=
 (__y - 1))

--

Roger