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Date: Mon, 22 Jan 2024 21:50:40 -0800
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Subject: Re: [RFC PATCH 0/8] cgroup/cpuset: Support RCU_NOCB on isolated
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To: =?UTF-8?Q?Michal_Koutn=C3=BD?= <mkoutny@suse.com>
Cc: Tejun Heo <tj@kernel.org>, Zefan Li <lizefan.x@bytedance.com>,
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References: <20240117163511.88173-1-longman@redhat.com>
 <bql5g22ovp2dm33llmq5oxpmuuhysvdyppj7j6xvrm643xuniv@pkqrwvmqzneh>
From: Waiman Long <longman@redhat.com>
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On 1/22/24 10:07, Michal Koutný wrote:
> Hello Waiman.
>
> On Wed, Jan 17, 2024 at 11:35:03AM -0500, Waiman Long <longman@redhat.com> wrote:
>> This patch series is based on the RFC patch from Frederic [1]. Instead
>> of offering RCU_NOCB as a separate option, it is now lumped into a
>> root-only cpuset.cpus.isolation_full flag that will enable all the
>> additional CPU isolation capabilities available for isolated partitions
>> if set. RCU_NOCB is just the first one to this party. Additional dynamic
>> CPU isolation capabilities will be added in the future.
> IIUC this is similar to what I suggested back in the day and you didn't
> consider it [1]. Do I read this right that you've changed your mind?

I didn't said that we were not going to do this at the time. It's just 
that more evaluation will need to be done before we are going to do 
this. I was also looking to see if there were use cases where such 
capabilities were needed. Now I am aware that such use cases do exist 
and we should start looking into it.

>
> (It's fine if you did, I'm only asking to follow the heading of cpuset
> controller.)

OK, the title of the cover-letter may be too specific. I will make it 
more general in the next version.

Cheers,
Longman