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([2620:10d:c092:600::2:457c]) by smtp.gmail.com with ESMTPSA id f12sm115966wru.81.2021.06.07.05.14.32 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Mon, 07 Jun 2021 05:14:32 -0700 (PDT) To: Thomas Gleixner , Jens Axboe , io-uring@vger.kernel.org Cc: Andres Freund , Ingo Molnar , Peter Zijlstra , Darren Hart , Davidlohr Bueso , linux-kernel@vger.kernel.org, Chris Mason References: <409a624c-de75-0ee5-b65f-ee09fff34809@gmail.com> <5ab4c8bd-3e82-e87b-1ae8-3b32ced72009@gmail.com> <87sg211ccj.ffs@nanos.tec.linutronix.de> <30bdf12c-6287-4c13-920c-bb5cc6ac02bf@gmail.com> <87k0nayojy.ffs@nanos.tec.linutronix.de> <87pmx1yse9.ffs@nanos.tec.linutronix.de> From: Pavel Begunkov Subject: Re: [RFC 4/4] io_uring: implement futex wait Message-ID: <2dbcf0b1-9cd9-1edc-08dc-5e758c68c0a3@gmail.com> Date: Mon, 7 Jun 2021 13:14:22 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.10.1 MIME-Version: 1.0 In-Reply-To: <87pmx1yse9.ffs@nanos.tec.linutronix.de> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 6/5/21 3:09 AM, Thomas Gleixner wrote: [...] > Here is _all_ the information you provided: > > 0) Cover letter: > > > Proof of concept for io_uring futex requests. The wake side does > > FUTEX_WAKE_OP type of modify-compare operation but with a single > > address. Wait reqs go through io-wq and so slow path. > > Describes WHAT it is supposed to do, but not at all WHY. > > Plus it describes it in terms which are maybe understandable for > io-uring aware people, but certainly not for the general audience. I actually agree with that and going to add it once I get details I needed. > > Should be interesting for a bunch of people, so we should first outline > > API and capabilities it should give. > > You post patches which _should_ be interesting for a unspecified bunch > of people, but you have no idea what the API and capabilities should > be? That's word carping. Some of the cases were known, but was more interested atm in others I heard only a brief idea about, that's why that person was CC'ed. > IOW, this follows the design principle of: Throw stuff at the wall and > see what sticks? Exactly what it is *not*. Emails were chosen to clarify details, nobody tells it wouldn't be reworked and adjusted. Do you imply I should discuss ideas privately? > But at the same time you want feedback from the people responsible for > the subsystems you are modifying without providing the required > information and worse: > > > As I almost never had to deal with futexes myself, would especially > > love to hear use case, what might be lacking and other blind spots. > > So you came up with a solution with no use case and expect the futex > people or whoever to figure out what you actually want to solve? Again, not true. Where did you get that? > [...] > Now let me quote Documentation/process/submitting-patches.rst: > > "Describe your problem. Whether your patch is a one-line bug fix or > 5000 lines of a new feature, there must be an underlying problem that > motivated you to do this work. Convince the reviewer that there is a > problem worth fixing and that it makes sense for them to read past the > first paragraph." > > Can you seriously point me to a single sentence in the above verbatim > quotes from your cover letter and changelogs which complies with that rule? > > It does not matter whether this is RFC or not. You simply ignore well > documented rules and then you get upset because I told you so: > > > 1) The proposed solution: I can't figure out from the changelogs or the > > cover letter what kind of problems it solves and what the exact > > semantics are. If you ever consider to submit futex patches, may I > > recommend to study Documentation/process and get some inspiration > > from git-log? > > And what's worse, you get impertinent about it: Impertinent? Was just keeping up with your nice way of conveying ideas. FWIW, it's not in particularly related to this small chunk above at all. > > I'm sorry you're incapable of grasping ideas quick > > Sure. I'm incompetent and stupid just because I can't figure out your > brilliant ideas which are so well described - let me quote again: That's your own interpretation, can't help you with that [...] > What's galling about that? > > - You wasted _my_ time by _not_ providing the information which I need > to digest your submission. > > - I went way beyond what Documentation/process/ says and read past the > first paragraph of useless information. > > - I provided you a detailed technical feedback nevertheless > > And as a result you attack me at a non-technical level. So where exactly > is the "we" and who started galling? If you think it was an attack, your response might have been interpreted in a such way as well, even though it haven't by me. There are enough of weird phrases and implications in your reply, but I have no intention of going through it and picking up on every phrase, would be useless >> Exactly why there was "we". I have my share of annoyance, which I would >> readily put aside if that saves me time. > > I grant you to be annoyed as much as you want. But you are getting > something fundamentaly wrong: > > "which I would readily put aside if that saves me time." > > As I told you above: You have been already wasting _my_ time by not > providing the information which is required to actually look at what you > propose. > >> Exactly why there was "we". I have my share of annoyance, which I would >> readily put aside if that saves me time. And that's the suggestion >> made > > In my first reply I made that a recommendation, so let me rephrease > that: > > Read and comply to Documentation/process! > > It does not matter at all how brilliant the idea you have is and how > stupid the reviewer at the other end might be. There are still rules to > follow and they apply to the most brilliant people on the planet. > > So, as I told you before: Try again. -- Pavel Begunkov