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From: "Chen, Kenneth W" <kenneth.w.chen@intel.com>
To: <linux-kernel@vger.kernel.org>
Subject: bug in sched.c:activate_task()
Date: Mon, 4 Oct 2004 19:16:39 -0700
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Update p->timestamp to "now" in activate_task() doesn't look right
to me at all.  p->timestamp records last time it was running on a
cpu.  activate_task shouldn't update that variable when it queues
a task on the runqueue.

This bug (and combined with others) triggers improper load balancing.

Patch against linux-2.6.9-rc3.  Didn't diff it against 2.6.9-rc3-mm2
because mm tree has so many change in sched.c.

Signed-off-by: Ken Chen <kenneth.w.chen@intel.com>


--- linux-2.6.9-rc3/kernel/sched.c.orig	2004-10-04 19:11:21.000000000 -0700
+++ linux-2.6.9-rc3/kernel/sched.c	2004-10-04 19:11:35.000000000 -0700
@@ -888,7 +888,6 @@ static void activate_task(task_t *p, run
 			p->activated = 1;
 		}
 	}
-	p->timestamp = now;

 	__activate_task(p, rq);
 }