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Date: Wed, 7 Nov 2001 21:26:11 -0800 (PST)
From: Linus Torvalds <torvalds@transmeta.com>
To: Krishna Kumar <kumarkr@us.ibm.com>
cc: Andreas Dilger <adilger@turbolabs.com>, <ak@muc.de>, <andrewm@uow.edu.au>,
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Subject: Re: [PATCH] net/ipv4/*, net/core/neighbour.c jiffies cleanup
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On Wed, 7 Nov 2001, Krishna Kumar wrote:
> >
> > In short: It is wrong to do
> >
> >          if (jiffies <= start+HZ)
> >
> > and it is _right_ to do
> >
> >          if (jiffies - start <= HZ)
>
> Actually this last part is wrong, isn't it ? jiffies <= start + HZ is also
> a correct way to do it, since start+HZ will overflow to the current value
> of jiffies when HZ time elapses. So the above two statements are IDENTICAL.

No.

Try it out with a few examples. You'll see.

		Linus

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