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Date: Fri, 11 Mar 2005 10:36:07 +0100
From: Ingo Molnar <mingo@elte.hu>
To: Scott Wood <scott@gw.timesys.com>
Cc: linux-kernel@vger.kernel.org, manas.saksena@timesys.com
Subject: Re: [PATCH] realtime-preempt: update inherited priorities on setscheduler
Message-ID: <20050311093607.GB19954@elte.hu>
References: <20050310212116.GA2420@yoda.timesys>
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* Scott Wood <scott@gw.timesys.com> wrote:

> -	p->prio = effective_prio(p);
> +	/* Don't overwrite an inherited RT priority with the static
> +	   RT priority. */
> +
> +	if (!rt_task(p))
> +		p->prio = effective_prio(p);

are you sure this is needed? The -RT code currently does this:

 static int effective_prio(task_t *p)
 {
         if (rt_task(p))
                 return p->prio;
         return __effective_prio(p);
 }

i.e. if it's an RT task then 'effective priority' is whatever it has
right now. I.e. 'p->prio = effective_prio(p)' will have no effect for RT
tasks. PI would not be working at all if we were overwriting the
inherited priority.

	Ingo