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Date: Mon, 14 Oct 2013 13:18:42 +0200
From: Peter Zijlstra <peterz@infradead.org>
To: Juri Lelli <juri.lelli@gmail.com>
Cc: tglx@linutronix.de, mingo@redhat.com, rostedt@goodmis.org, oleg@redhat.com,
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        bruce.ashfield@windriver.com--no-chain-reply-to
Subject: Re: [PATCH 03/14] sched: SCHED_DEADLINE structures & implementation.
Message-ID: <20131014111842.GB3081@twins.programming.kicks-ass.net>
References: <1381747426-31334-1-git-send-email-juri.lelli@gmail.com>
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On Mon, Oct 14, 2013 at 12:43:35PM +0200, Juri Lelli wrote:
> @@ -1693,8 +1701,14 @@ void sched_fork(struct task_struct *p)
>  		p->sched_reset_on_fork = 0;
>  	}
>  
> -	if (!rt_prio(p->prio))
> +	if (dl_prio(p->prio)) {
> +		put_cpu();
> +		return -EAGAIN;

Is this really the error we want to return on fork()?

EAGAIN to me indicates a spurious error and we should try again later;
however as it obvious from the code above; we'll always fail, there's no
point in trying again later.

I would think something like EINVAL; even though there are no arguments
to fork(); would me a better option.

Then again; I really don't care too much; anybody any preferences?