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Date: Sat, 23 Jan 2016 18:33:11 -0600 (CST)
From: Christoph Lameter <cl@linux.com>
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To: Mike Galbraith <umgwanakikbuti@gmail.com>
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Subject: Re: fast path cycle muncher (vmstat: make vmstat_updater deferrable
 again and shut down on idle)
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On Sat, 23 Jan 2016, Mike Galbraith wrote:

> While you're fixing that commit up, can you perhaps find a better home
> for quiet_vmstat()?  It not only munches cycles when switching cross
> -core mightily, for -rt it injects a sleeping lock into the idle task.

Not sure what you are talking about. No sleeping locks are used in
quiet_vmstat() nor does it switch across cores. It would be broken if it
would do so.