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Date: Thu, 19 Apr 2012 13:23:57 +0300
From: Peter De Schrijver <pdeschrijver@nvidia.com>
To: Daniel Lezcano <daniel.lezcano@linaro.org>
CC: "Shilimkar, Santosh" <santosh.shilimkar@ti.com>,
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Subject: Re: [RFC PATCH] cpuidle: allow per cpu latencies
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On Thu, Apr 19, 2012 at 11:14:27AM +0200, Daniel Lezcano wrote:
> On 04/16/2012 05:34 PM, Peter De Schrijver wrote:
> >>
> >> Maybe we also want to make the 'disabled' flag per CPU then or provide some
> >> other way the number of C states can be different per CPU?
> >
> > What do you think about this? Do we also want to make the disabled flag per
> > CPU? Or how should we deal with a different number of C states per CPU?
> 
> Hi Peter,
> 
> yes, that could makes sense. But in most of the architecture, this is 
> not needed, so duplicating the state's array and latencies is unneeded 
> memory consumption.
> 
> Maybe we can look for a COW approach, similar to what is done for the 
> nsproxy structure, no ?
> 

That could be easily solved by just having a pointer to the state table in the
per CPU datastructure I think?


Cheers,

Peter.