From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-3.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 28BB4C433F5 for ; Fri, 17 Sep 2021 22:25:59 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 0F9A861041 for ; Fri, 17 Sep 2021 22:25:59 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1344721AbhIQW1R (ORCPT ); Fri, 17 Sep 2021 18:27:17 -0400 Received: from outgoing-auth-1.mit.edu ([18.9.28.11]:55134 "EHLO outgoing.mit.edu" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S232719AbhIQW1M (ORCPT ); Fri, 17 Sep 2021 18:27:12 -0400 Received: from cwcc.thunk.org (pool-72-74-133-215.bstnma.fios.verizon.net [72.74.133.215]) (authenticated bits=0) (User authenticated as tytso@ATHENA.MIT.EDU) by outgoing.mit.edu (8.14.7/8.12.4) with ESMTP id 18HMPY8h005995 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Fri, 17 Sep 2021 18:25:34 -0400 Received: by cwcc.thunk.org (Postfix, from userid 15806) id 3CFF515C0098; Fri, 17 Sep 2021 18:25:34 -0400 (EDT) Date: Fri, 17 Sep 2021 18:25:34 -0400 From: "Theodore Ts'o" To: Kent Overstreet Cc: Johannes Weiner , Dave Chinner , "Darrick J. Wong" , Matthew Wilcox , Linus Torvalds , linux-mm@kvack.org, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, Andrew Morton , Christoph Hellwig , David Howells Subject: Re: Folio discussion recap Message-ID: References: <20210916025854.GE34899@magnolia> <20210917052440.GJ1756565@dread.disaster.area> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Sep 17, 2021 at 05:13:10PM -0400, Kent Overstreet wrote: > Also: it's become pretty clear to me that we have crappy > communications between MM developers and filesystem > developers. I think one of the challenges has been the lack of an LSF/MM since 2019. And it may be that having *some* kind of ad hoc technical discussion given that LSF/MM in 2021 is not happening might be a good thing. I'm sure if we asked nicely, we could use the LPC infrasutrcture to set up something, assuming we can find a mutually agreeable day or dates. > Internally both teams have solid communications - I know > in filesystem land we all talk to each other and are pretty good at > working colaboratively, and it sounds like the MM team also has good > internal communications. But we seem to have some problems with > tackling issues that cross over between FS and MM land, or awkwardly > sit between them. That's a bit of a over-generalization; it seems like we've uncovered that some of the disagreemnts are between different parts of the MM community over the suitability of folios for anonymous pages. And it's interesting, because I don't really consider Willy to be one of "the FS folks" --- and he has been quite diligent to reaching out to a number of folks in the FS community about our needs, and it's clear that this has been really, really helpful. There's no question that we've had for many years some difficulties in the code paths that sit between FS and MM, and I'd claim that it's not just because of communications, but the relative lack of effort that was focused in that area. The fact that Willy has spent the last 9 months working on FS / MM interactions has been really great, and I hope it continues. That being said, it sounds like there are issues internal to the MM devs that still need to be ironed out, and at the risk of throwing the anon-THP folks under the bus, if we can land at least some portion of the folio commits, it seems like that would be a step in the right direction. Cheers, - Ted