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From: Linus Torvalds <torvalds@linux-foundation.org>
Date: Tue, 11 Jun 2024 14:34:56 -0700
Message-ID: <CAHk-=wg8APE61e5Ddq5mwH55Eh0ZLDV4Tr+c6_gFS7g2AxnuHQ@mail.gmail.com>
Subject: Re: [PATCHSET v6] sched: Implement BPF extensible scheduler class
To: Tejun Heo <tj@kernel.org>
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[ Tejun reminded me about this, and discussion hasn't really gone
anywhere for much too long, so now I just need to be the person who
makes a decision and people can hate on ]

On Wed, 1 May 2024 at 08:13, Tejun Heo <tj@kernel.org> wrote:
>
> This is v6 of sched_ext (SCX) patchset.
>
> During the past five months, both the development and adoption of sched_ext
> have been progressing briskly. Here are some highlights around adoption:
[...]

I honestly see no reason to delay this any more. This whole patchset
was the major (private) discussion at last year's kernel maintainer
summit, and I don't find any value in having the same discussion
(whether off-list or as an actual event) at the upcoming maintainer
summit one year later, so to make any kind of sane progress, my
current plan is to merge this for 6.11.

At least that way, we're making progress, and the discussion at KS
2024 can be about my mental acuity - or lack thereof - rather than
about rehashing the same thing that clearly made no progress last
year.

I've never been a huge believer in trying to make everybody happy with
code that is out of tree - we're better off working together on it
in-tree.

And using the "in order to accept this, some other thing has to be
fixed first" argument doesn't really work well either (and _that_ has
been discussed for over a decade at various maintainer summits).

Maybe the people who have concerns about this can work on those
concerns when it's in-tree.

I'm also not a believer in the argument that has been used (multiple
times) that the BPF scheduler would keep people from participating in
scheduler development. I personally think the main thing that keeps
people from participating is too high barriers to participation.

Anyway, this is the heads-up to Tejun to please just send me a pull
request for the next merge window.

And for everybody else as a "It's happening" heads-up.

[ Please just mentally insert the "IT'S HAPPENING" meme gif here -
because if I actually were to include it here, lkml would just reject
this email. Sometimes the anti-html rules don't work in our favor ].

                Linus