Re: Folios for 5.15 request - Was: re: Folio discussion recap -

From: Chris Mason
Date: Wed Sep 22 2021 - 12:56:25 EST



> On Sep 22, 2021, at 12:26 PM, Matthew Wilcox <willy@xxxxxxxxxxxxx> wrote:
>
> On Wed, Sep 22, 2021 at 11:46:04AM -0400, Kent Overstreet wrote:
>> On Wed, Sep 22, 2021 at 11:08:58AM -0400, Johannes Weiner wrote:
>>> On Tue, Sep 21, 2021 at 05:22:54PM -0400, Kent Overstreet wrote:
>>>> - it's become apparent that there haven't been any real objections to the code
>>>> that was queued up for 5.15. There _are_ very real discussions and points of
>>>> contention still to be decided and resolved for the work beyond file backed
>>>> pages, but those discussions were what derailed the more modest, and more
>>>> badly needed, work that affects everyone in filesystem land
>>>
>>> Unfortunately, I think this is a result of me wanting to discuss a way
>>> forward rather than a way back.
>>>
>>> To clarify: I do very much object to the code as currently queued up,
>>> and not just to a vague future direction.
>>>
>>> The patches add and convert a lot of complicated code to provision for
>>> a future we do not agree on. The indirections it adds, and the hybrid
>>> state it leaves the tree in, make it directly more difficult to work
>>> with and understand the MM code base. Stuff that isn't needed for
>>> exposing folios to the filesystems.
>>>
>>> As Willy has repeatedly expressed a take-it-or-leave-it attitude in
>>> response to my feedback, I'm not excited about merging this now and
>>> potentially leaving quite a bit of cleanup work to others if the
>>> downstream discussion don't go to his liking.
>
> We're at a take-it-or-leave-it point for this pull request. The time
> for discussion was *MONTHS* ago.
>

I’ll admit I’m not impartial, but my fundamental goal is moving the patches forward. Given folios will need long term maintenance, engagement, and iteration throughout mm/, take-it-or-leave-it pulls seem like a recipe for future conflict, and more importantly, bugs.

I’d much rather work it out now.

-chris