From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: [PATCH] NET : rt_check_expire() can take a long time, add a
 cond_resched()
Date: Thu, 15 Nov 2007 00:52:08 -0800 (PST)
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From: Andi Kleen <andi@firstfloor.org>
Date: Thu, 15 Nov 2007 08:30:16 +0100

> Eric Dumazet <dada1@cosmosbay.com> writes:
> >
> > Using a "if (need_resched())" test before calling "cond_resched();" is
> > necessary to avoid spending too much time doing the resched check.
> 
> The only difference between cond_resched() and if (need_resched())
> cond_resched() is one function call less and one might_sleep less. If
> the might_sleep or the function call are really problems (did you
> measure it? -- i doubt it somewhat) then it would be better to fix the
> generic code to either inline that or supply a __cond_resched()
> without might_sleep.
> 
> A cheaper change might have been to just limit the number of buckets
> scanned.

Fix up unmap_vmas() too if this is done as it does a similar
need_resched() check too.