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Date: Thu, 2 Dec 2004 14:49:34 +0100
From: Ingo Molnar <mingo@elte.hu>
To: Florian Schmidt <mista.tapas@gmx.net>
Cc: Rui Nuno Capela <rncbc@rncbc.org>, linux-kernel@vger.kernel.org,
       Lee Revell <rlrevell@joe-job.com>, mark_h_johnson@raytheon.com,
       "K.R. Foley" <kr@cybsft.com>, Bill Huey <bhuey@lnxw.com>,
       Adam Heath <doogie@debian.org>, Thomas Gleixner <tglx@linutronix.de>,
       Michal Schmidt <xschmi00@stud.feec.vutbr.cz>,
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       Shane Shrybman <shrybman@aei.ca>, Amit Shah <amit.shah@codito.com>,
       Esben Nielsen <simlo@phys.au.dk>, Andrew Morton <akpm@osdl.org>
Subject: Re: [patch] Real-Time Preemption, -RT-2.6.10-rc2-mm3-V0.7.31-19
Message-ID: <20041202134934.GA32216@elte.hu>
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* Florian Schmidt <mista.tapas@gmx.net> wrote:

> Ok, so if i want to find out whether a client violates the RT
> constraints for its process callback i would have to add a call to
> gettimeofday(1,1) at the start of the process callback and
> gettimeofday(1,0) at the end.
> 
> Everything which causes a reschedule inbetween will then cause SIGUSR2
> to be sent to the client for which i could either add a signal handler
> in the client or just use gdb to get notified of it. 

correct. I'd expect there to be a number of less critical reschedules
happening around startup/shutdown of a client, which one could consider
a false positive, but there should be no unexpected rescheduling while
the client is up and running.

	Ingo