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Date: Fri, 28 Oct 2016 09:43:29 +0200
From: Peter Zijlstra <peterz@infradead.org>
To: Vikram Mulukutla <markivx@codeaurora.org>
Cc: linux-kernel@vger.kernel.org, Ingo Molnar <mingo@kernel.org>,
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        Vikram Mulukutla <markivx@codeauorora.org>
Subject: Re: [RFC PATCH 2/3] sched: Introduce Window-Assisted CPU utilization
 Tracking
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On Fri, Oct 28, 2016 at 12:10:41AM -0700, Vikram Mulukutla wrote:
> +u64 walt_ktime_clock(void)
> +{
> +	if (unlikely(walt_ktime_suspended))
> +		return ktime_to_ns(ktime_last);
> +	return ktime_get_ns();
> +}

> +static int walt_suspend(void)
> +{
> +	ktime_last = ktime_get();
> +	walt_ktime_suspended = true;
> +	return 0;
> +}

No, ktime_get() will not be used in the scheduler. Imagine the joy if
that thing ends up being the HPET.