回复: [PATCH v2] kthread_worker: re-set CPU affinities if CPU come online

[Zhang, Qiang]

________________________________________
发件人: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
发送时间: 2020年10月28日 16:30
收件人: Zhang, Qiang; pmladek@xxxxxxxx; tj@xxxxxxxxxx
抄送: akpm@xxxxxxxxxxxxxxxxxxxx; linux-mm@xxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx
主题: Re: [PATCH v2] kthread_worker: re-set CPU affinities if CPU come online

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On Wed, Oct 28 2020 at 15:30, qiang zhang wrote:
> From: Zqiang <qiang.zhang@xxxxxxxxxxxxx>
>
> When someone CPU offlined, the 'kthread_worker' which bind this CPU,
> will run anywhere, if this CPU online, recovery of 'kthread_worker'
> affinity by cpuhp notifiers.
>
> Signed-off-by: Zqiang <qiang.zhang@xxxxxxxxxxxxx>
> ---
>  v1->v2:
>  rename variable kworker_online to kthread_worker_online.
>  add 'cpuhp_node' and 'bind_cpu' init in KTHREAD_WORKER_INIT.
>  add a comment explaining for WARN_ON_ONCE.

>How is that addressing any of the comments I made on V1 of this?

Do you mean the following problem:
 
"The dynamic hotplug states run late. What's preventing work to be queued
on such a worker before it is bound to the CPU again?"

Thanks
Qiang
>
>Thanks,
>
>       tglx