From mboxrd@z Thu Jan  1 00:00:00 1970
From: Honghui Zhang <zhanghonghui@huawei.com>
Subject: Re: [PATCH] sched/rt: Decrease number of calls of push_rt_task()
 in push_rt_tasks()
Date: Tue, 5 Feb 2013 16:25:11 +0800
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Cc: Steven Rostedt <rostedt@goodmis.org>,
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	Peter Zijlstra <peterz@infradead.org>,
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To: Kirill Tkhai <tkhai@yandex.ru>
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On 2013/2/5 15:22, Kirill Tkhai wrote:
>>
>> Suppose we have a large number of cpus(say 4096), with the last one running
>> a low-priority task on it. Is it possible with this patch we will never reach
>> the last cpu in case that previous cpu has complete the pulled task?
> 
> Yes. But this patch is about several pushable tasks on the same cpu.
> 
> Kirill
> 

Maybe I haven't make myself understood, but in that case, there will be a higher-priority
task in the runqueue of the pushing cpu, and a lower-priority task running in the last cpu
which could not be preempt by push_rt_task(),  I don't think it's acceptable.

Hans