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Sender: Tejun Heo <htejun@gmail.com>
Date: Thu, 2 May 2024 09:20:15 -1000
From: Tejun Heo <tj@kernel.org>
To: Peter Zijlstra <peterz@infradead.org>
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Subject: Re: [PATCHSET v6] sched: Implement BPF extensible scheduler class
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 <20240502084800.GY30852@noisy.programming.kicks-ass.net>
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Hello, Peter.

On Thu, May 02, 2024 at 10:48:00AM +0200, Peter Zijlstra wrote:
> Can you please put your efforts and the touted Google collaboration in
> fixing the existing cgroup mess?

I suppose you're referring to Rik's flattened hierarchy patchset.

  https://lore.kernel.org/all/20190822021740.15554-1-riel@surriel.com

Rik spent a lot of time and energy on it and IIRC one of the reasons why it
didn't get pushed further was the lack of any enthusiasm or support from the
upstream community.

We can resurrect the discussion on that patchset but how is that connected
to sched_ext? One of the example schedulers, scx_flatcg, does employ the
same approach with a twist (instead of flattening completely, it builds
two-level hierarchy so that a leaf cgroup can be treated as a single entity)
to demonstrate the idea but the two projects don't really have much in
common otherwise. Are you saying that Meta and Google working on the
flattened hierarchy is a prerequisite for landing sched_ext?

Thanks.

-- 
tejun