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Subject: Re: [RFC][PATCH 02/11] sched: SCHED_DEADLINE policy implementation.
From: Peter Zijlstra <peterz@infradead.org>
To: Raistlin <raistlin@linux.it>
Cc: Ingo Molnar <mingo@elte.hu>, Thomas Gleixner <tglx@linutronix.de>,
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Date: Tue, 13 Apr 2010 20:22:16 +0200
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On Sun, 2010-02-28 at 20:17 +0100, Raistlin wrote:
> +       /*
> +        * Arm the timer to fire at wakeup, tying to compensate for
> +        * the fact that wakeup is actually coming from rq->clock and
> +        * not from hrtimer's time base reading.
> +        */
> +       act = ns_to_ktime(wakeup);
> +       now = hrtimer_cb_get_time(&dl_se->dl_timer);
> +       delta = ktime_to_ns(now) - rq->clock;
> +       act = ktime_add_ns(act, delta); 

This is sad, but I'm afraid a reality we have to live with..