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Date:   Thu, 7 Jul 2022 14:59:13 +0800
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Subject: Re: [Question] The system may be stuck if there is a cpu cgroup
 cpu.cfs_quato_us is very low
To:     Tejun Heo <tj@kernel.org>, Benjamin Segall <bsegall@google.com>
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From:   Zhang Qiao <zhangqiao22@huawei.com>
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在 2022/7/2 4:15, Tejun Heo 写道:
> On Fri, Jul 01, 2022 at 01:08:21PM -0700, Benjamin Segall wrote:
>> Yes, fixing (kernel) priority inversion due to CFS_BANDWIDTH requires a
>> serious reworking of how it works, because it would need to dequeue
>> tasks individually rather than doing the entire cfs_rq at a time (and
>> would require some effort to avoid pinging every throttling task to get
>> it into the kernel).
> 
> Right, I don't have a good idea on evolving the current implementation
> into something correct. As you pointed out, we need to account along
> the sched_group tree but conditionally enforce on each thread.
> 
> Thanks.
> 

Understood. Thanks for your detailed explanation.

Thanks.
--
Qiao
.