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Date: Mon, 11 Nov 2013 17:43:04 -0500 (EST)
From: Nicolas Pitre <nicolas.pitre@linaro.org>
To: Arjan van de Ven <arjan@linux.intel.com>
cc: Catalin Marinas <catalin.marinas@arm.com>,
        Morten Rasmussen <morten.rasmussen@arm.com>,
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Subject: Re: [RFC][PATCH v5 00/14] sched: packing tasks
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On Mon, 11 Nov 2013, Arjan van de Ven wrote:

> On 11/11/2013 10:31 AM, Catalin Marinas wrote:
> > I agree, we can't rely on the requested C-state but the_actual_  state
> > and this means querying the hardware driver. Can we abstract this via
> > some interface which provides the cost of waking up a CPU? This could
> > take into account the state of the other CPUs in the cluster and the
> > scheduler is simply concerned with the wake-up costs.
> 
> can you even query this without actually waking up the cpu and asking ???

On those systems we're interested in we sure can.


Nicolas