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Reply-To: "Hillf Danton" <hillf.zj@alibaba-inc.com>
From: "Hillf Danton" <hillf.zj@alibaba-inc.com>
To: "'Vincent Guittot'" <vincent.guittot@linaro.org>
Cc: "'Wanpeng Li'" <kernellwp@gmail.com>,
        "'Peter Zijlstra'" <peterz@infradead.org>,
        "'Ingo Molnar'" <mingo@kernel.org>,
        "'linux-kernel'" <linux-kernel@vger.kernel.org>,
        "'Preeti U Murthy'" <preeti@linux.vnet.ibm.com>,
        "'Morten Rasmussen'" <Morten.Rasmussen@arm.com>,
        "'Kamalesh Babulal'" <kamalesh@linux.vnet.ibm.com>
Subject: Re: [PATCH v8 03/10] sched: move cfs task on a CPU with higher capacity
Date: Tue, 04 Nov 2014 20:07:44 +0800
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> >>   +     /*
> >> +        * The dst_cpu is idle and the src_cpu CPU has only 1 CFS task.
> >
> >
> > Why specify one task instead of not less than one?
> 
> if cfs.h_nr_running = 0 (which should not occurs at that point), we
> don't need to do more test to check if it's worth moving the task
> because there is no task to move.
> 
I wonder if you can please shed light on the case that 
the dst_cpu is newly idle.

Thanks
Hillf