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Date:   Tue, 4 Apr 2023 15:31:24 -0700
From:   Andrew Morton <akpm@linux-foundation.org>
To:     Yosry Ahmed <yosryahmed@google.com>,
        Alexander Viro <viro@zeniv.linux.org.uk>,
        "Darrick J. Wong" <djwong@kernel.org>,
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Subject: Re: [PATCH v4 0/3] Ignore non-LRU-based reclaim in memcg reclaim
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On Tue, 4 Apr 2023 15:28:16 -0700 Andrew Morton <akpm@linux-foundation.org> wrote:

> On Tue, 4 Apr 2023 15:00:57 -0700 Yosry Ahmed <yosryahmed@google.com> wrote:
> 
> > ...
> >
> > > >
> > > > Without refactoring the code that adds reclaim_state->reclaimed to
> > > > scan_control->nr_reclaimed into a helper (flush_reclaim_state()), the
> > > > change would need to be done in two places instead of one, and I
> > > > wouldn't know where to put the huge comment.
> > >
> > > Well, all depends on how desirable it it that we backport.  If "not
> > > desirable" then leave things as-is.  If at least "possibly desirable"
> > > then a simple patch with the two changes and no elaborate comment will
> > > suit.
> > >
> > 
> > I would rather leave the current series as-is with an elaborate
> > comment. I can send a separate single patch as a backport to stable if
> > this is something that we usually do (though I am not sure how to
> > format such patch).
> 
> -stable maintainers prefer to take something which has already been
> accepted by Linus.
> 
> The series could be as simple as
> 
> simple-two-liner.patch
> revert-simple-two-liner.patch
> this-series-as-is.patch
> 
> simple-two-liner.patch goes into 6.3-rcX and -stable.  The other
> patches into 6.4-rc1.  

But the key question remains: how desirable is a backport?

Looking at the changelogs I'm not seeing a clear statement of the
impact upon real-world users' real-world workloads.  (This is a hint). 
So I am unable to judge.

Please share your thoughts on this.