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Message-ID: <9810cff90802221121s216f69f4k4a5f39eaaf11dd7f@mail.gmail.com>
Date: Fri, 22 Feb 2008 11:21:14 -0800
From: "Bill Huey (hui)" <bill.huey@gmail.com>
To: paulmck@linux.vnet.ibm.com
Subject: Re: [PATCH [RT] 08/14] add a loop counter based timeout mechanism
Cc: "Andi Kleen" <ak@suse.de>, "Gregory Haskins" <ghaskins@novell.com>,
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       dsaxena@plexity.net, gregkh@suse.de, sdietrich@novell.com,
       pmorreale@novell.com, mkohari@novell.com
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On Fri, Feb 22, 2008 at 11:19 AM, Bill Huey (hui) <bill.huey@gmail.com> wrote:
>  Yeah, I'm not very keen on having a constant there without some
>  contention instrumentation to see how long the spins are. It would be
>  better to just let it run until either task->on_cpu is off or checking
>  if the "current" in no longer matches the mutex owner for the runqueue
>  in question. At that point, you know the thread isn't running.
>  Spinning on something like that is just a waste of time. It's for that
>  reason that doing in the spin outside of a preempt critical section
>  isn't really needed

Excuse me, I meant to say "...isn't a problem".

bill
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