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Date: Thu, 17 Oct 2002 19:52:27 +0100
From: Dave Jones <davej@codemonkey.org.uk>
To: Robin Holt <holt@sgi.com>
Cc: Dave Jones <davej@codemonkey.org.uk>, John Hesterberg <jh@sgi.com>,
       linux-kernel@vger.kernel.org
Subject: Re: [PATCH] 2.5.43 CSA, Job, and PAGG
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On Thu, Oct 17, 2002 at 12:50:52PM -0500, Robin Holt wrote:

 > > The first two lines in the csa patch contain an obvious jiffy-wrap bug.
 > 
 > Fixed.  The patch file named above is now a link to
 > linux-2.5.43_002-csa.patch.  The old file is linux-2.5.43_001-csa.patch
 > 
 > If you could re-review, I would appreciate it.

Casting it to a ulong won't help you.
Imagine jiffies begins at 0xffffffff

	unsigned long start_wait = jiffies;
	...
	current->bwtime += (unsigned long) jiffies - start_wait;

and when you read it the second time, it's rolled over to 0x00000001

You now increment bwtime by $BIGNUM

-- 
| Dave Jones.        http://www.codemonkey.org.uk
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