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Date: Thu, 14 Jan 2016 20:47:52 +0100
From: Peter Zijlstra <peterz@infradead.org>
To: Luca Abeni <luca.abeni@unitn.it>
Cc: linux-kernel@vger.kernel.org, Ingo Molnar <mingo@redhat.com>,
        Juri Lelli <juri.lelli@arm.com>
Subject: Re: [RFC 4/8] Improve the tracking of active utilisation
Message-ID: <20160114194752.GD6357@twins.programming.kicks-ass.net>
References: <1452785094-3086-1-git-send-email-luca.abeni@unitn.it>
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On Thu, Jan 14, 2016 at 04:24:49PM +0100, Luca Abeni wrote:

> +	if (!hrtimer_is_queued(timer)) {
> +		hrtimer_start(timer, act, HRTIMER_MODE_ABS);
> +	}
> +
> +	if (hrtimer_active(timer) == 0) {
> +		printk("Problem activating inactive_timer!\n");
> +		clear_running_bw(dl_se, dl_rq);
> +		if (!dl_task(p)) {
> +			__dl_clear_params(p);
> +		}
> +	} else {
> +		get_task_struct(p);

Ah, I missed that one. I would suggest putting that right _before_
hrtimer_start(), because hrtimer_start() guarantees the callback will
run.

> +	}