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Date: Wed, 13 Oct 2010 19:29:02 +0530
From: Balbir Singh <balbir@linux.vnet.ibm.com>
To: Nikhil Rao <ncrao@google.com>
Cc: Bharata B Rao <bharata@linux.vnet.ibm.com>, linux-kernel@vger.kernel.org,
        Dhaval Giani <dhaval.giani@gmail.com>,
        Vaidyanathan Srinivasan <svaidy@linux.vnet.ibm.com>,
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        Ingo Molnar <mingo@elte.hu>, Peter Zijlstra <a.p.zijlstra@chello.nl>,
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        Herbert Poetzl <herbert@13thfloor.at>, Avi Kivity <avi@redhat.com>,
        Chris Friesen <cfriesen@nortel.com>, Paul Menage <menage@google.com>,
        Mike Waychison <mikew@google.com>, Paul Turner <pjt@google.com>
Subject: Re: [PATCH v3 2/7] sched: accumulate per-cfs_rq cpu usage
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* Nikhil Rao <ncrao@google.com> [2010-10-13 06:46:18]:

> > Quick question for cfs_b->quota == RUNTIME_INF, won't cfs_b->runtime
> > be always > 0?
> 
> Hi Balbir,
> 
> cfs_b->runtime can be 0 if the task group exhausts its quota.
> cfs_b->runtime is a counter that is periodically refreshed to
> cfs_b->quota, and is decremented every time a cfs_rq requests a slice.
>

Thanks, Nikhil

I saw several checks for quota == RUNTIME_INF and saw updates not
happening. Do we track usage for cgroups with infinite quota? IOW, is
runtime updated? If so, why?

-- 
	Three Cheers,
	Balbir