Subject: Re: 2.6.16-rc6-rt1
From: Thomas Gleixner <tglx@linutronix.de>
Reply-To: tglx@linutronix.de
To: Ingo Molnar <mingo@elte.hu>
Cc: Esben Nielsen <simlo@phys.au.dk>, linux-kernel@vger.kernel.org
In-Reply-To: <20060314221111.GA7118@elte.hu>
References: <20060314101811.GA10450@elte.hu>
	 <Pine.LNX.4.44L0.0603142256050.1291-100000@lifa01.phys.au.dk>
	 <20060314221111.GA7118@elte.hu>
Content-Type: text/plain
Date: Tue, 14 Mar 2006 23:22:17 +0100
Message-Id: <1142374937.19916.665.camel@localhost.localdomain>
Mime-Version: 1.0
Content-Transfer-Encoding: 7bit
Sender: linux-kernel-owner@vger.kernel.org
Content-Length: 889
Lines: 21

On Tue, 2006-03-14 at 23:11 +0100, Ingo Molnar wrote:
> > > no. We have to run deadlock detection to avoid things like circular lock
> > > dependencies causing an infinite schedule+wakeup 'storm' during priority
> > > boosting. (like possible with your wakeup based method i think)
> > No, all tasks would just settle on the highest priority and then the
> > wakeups would stop.
> 
> you are right, that shouldnt be possible. But how about other, SMP 
> artifacts? What if the woken up task runs on another CPU, and the whole 
> chain of boosting is thus delayed?

And it does not solve the problem of ad hoc deadlock detection at all.

	tglx


-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/