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From: Andreas Dilger <adilger@clusterfs.com>
Date: Tue, 27 Aug 2002 18:41:54 -0600
To: Daniel Phillips <phillips@arcor.de>
Cc: Andrew Morton <akpm@zip.com.au>, Lahti Oy <rlahti@netikka.fi>,
       linux-kernel@vger.kernel.org
Subject: Re: [PATCH] sched.c
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References: <000b01c24df5$aacc7ed0$d20a5f0a@deldaran> <3D6BC685.216B5B67@zip.com.au> <E17jqSE-0002jN-00@starship>
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On Aug 28, 2002  02:13 +0200, Daniel Phillips wrote:
> On Tuesday 27 August 2002 20:35, Andrew Morton wrote:
> > Lahti Oy wrote:
> > > - for (i = 0; i < NR_CPUS; i++)
> > > + for (i = NR_CPUS; i; i--)
> > >    sum += cpu_rq(i)->nr_running;
> > 
> > Off-by-one there.  You'd want
> > 
> > 	for (i = NR_CPUS; --i >= 0; )
> > 
> > or something similarly foul ;)
> 
> 	int i = NR_CPUS;
> 
> 	while (--i)

Actually, I prefer the following to avoid wrap-around conditions in
strange circumstances (i.e. if 'i' is manipulated between setting
and the while loop):

	while (i-- > 0) {
		...
	}

Cheers, Andreas
--
Andreas Dilger
http://www-mddsp.enel.ucalgary.ca/People/adilger/
http://sourceforge.net/projects/ext2resize/