Re: [PATCH v5] sched/deadline: support dl task migration during cpu hotplug

From: Wanpeng Li
Date: Thu Nov 20 2014 - 04:10:18 EST


Hi Peterz, Juri,
On Thu, Nov 13, 2014 at 01:21:31PM +0300, Kirill Tkhai wrote:
>> > Also, we should think about the following situation.
>> >
>> > DL task is left on dead rq. In your scheme it will be moved by the timer.
>> > But what will be if somebody changes the class of the task (before timer)?
>>
>> I think timer will be cancelled in switched_from_dl().
>
>Yeah, but nobody will move this task to alive rq.
>
>> > In this case the task still remains on dead rq.
>> >
>> > We should handle this situation in some way.

I think pang's patch handle the exclusive cpusets rd->span issue, the concern
which Kirill mentioned above maybe the last one block the patch merged, is
there any idea or proposal from you experts?

Regards,
Wanpeng Li

>> >
>> > Kirill
>> >
>> >
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