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Re:No nuances, just buggy code (was: related to Spinlock imp... by csande17 on Sunday January 05, 2020 @02:05AM (#21960103)
I personally really appreciated the additional details in Linus's version.

When I read your version, I learn that spin locks are not a drop-in replacement for uncontested mutexes. That's great, except that I don't really know for sure what either of those terms mean, and also I didn't gain any knowledge that doesn't relate to this specific situation. It also wasn't super convincing -- I could just as easily see someone post a reply saying "well actually spin locks ARE a drop-in something something mutex" and I'd have no way to tell who was right.

Linus, on the other hand, told me about the mechanism by which the problem happens. I learned about how the scheduler sees spin-locks' loops, and that the main advantage of "real" mutexes is that the scheduler knows who's waiting on what. I also wouldn't necessarily have realized the "take clock measurement, then get descheduled before you release the lock" issue if he hadn't called it out specifically.

Sure, I guess "garbage" comes off a little mean, but "the author has a common misconception" almost sounds more passive-aggressive to me.

Re:No nuances, just buggy code (was: related to Spinlock imp... by simias on Sunday January 05, 2020 @02:38AM (#21960184)
The first section of Linus's answer reads really rough to me and almost made me stop reading, imagining that it was going to be yet an other entry in the "Linus bullies some poor coder into submission by insulting them until they just stop responding" which is a shame because there's a lot of interesting content after that. I guess I invite the people who had the same knee-jerk reaction I had to give the post a 2nd chance and power through Linus' unnecessarily harsh tone to get to the good stuff.

>Sure, I guess "garbage" comes off a little mean, but "the author has a common misconception" almost sounds more passive-aggressive to me.

The latter might be slightly passive-aggressive (although it doesn't have to be), the former is simply aggressive-aggressive.

Re:No nuances, just buggy code (was: related to Spinlock imp... by needs on Sunday January 05, 2020 @04:20AM (#21960456)
As long as Linus is blaming the work done and not the people behind it, that's fine. Something truly aggressive would be "This benchmark is garbage and the people responsible for writing it are monkeys on crack". He did such things in the past, but in the 4 emails I got to find on this specific benchmark, none of them critic people writing code.

I think Linus got upset that a badly designed benchmark got popular and therefor is spreading misconceptions. His strongly worded answer is getting popular too and as a result everybody learns and he has stopped an urban legend from spreading. A success on every points.

Re:No nuances, just buggy code (was: related to Spinlock imp... by simias on Sunday January 05, 2020 @05:06AM (#21960580)
>As long as Linus is blaming the work done and not the people behind it, that's fine.

I think your comment is just wrong and generally pure garbage. I can't believe some poor server will have to host this nonsense for years to come. It's the most inane thing I've read all year.

I'm just talking about your comment, not you though, so clearly no hard feelings here and it's definitely the right way to frame my argument to have a nice, peaceful and constructive technical discussion.

Re:No nuances, just buggy code (was: related to Spinlock imp... by AndriyKunitsyn on Sunday January 05, 2020 @06:59AM (#21960896)
No, reductio ad absurdum is not an argument. What you wrote is an exercise in swearing. What Linus wrote is getting his point across.

It is certainly possible to describe a code with bad words without hurting the feelings of person who made it, and I think, in order for it to work everyone has to understand that everybody writes “garbage” or “crap” code sometimes, so when it happens, it’s not a big deal; it shouldn’t hurt your professional dignity.

On my job, in team of 4, we do it from time to time and it’s just much mentally easier, streamlined - and yes, constructive to conduct code reviews this way. I understand this may not work for other, bigger teams, but it’s certainly a valid way.

Re:No nuances, just buggy code (was: related to Spinlock imp... by polishTar on Sunday January 05, 2020 @12:04PM (#21962224)
There were ways for him to communicate those same ideas less negatively.

And it was more than just the "garbage" line. It was also things like "If I haven't convinced you of that by now, I don't know what I can say.", and "See how simplistic - and self-centered - your expectation is?".

Writing this way doesn't "streamline" anything. I interpreted it as a negative interaction, and clearly others have as well including the original author (since he said as much in his response).

Re:No nuances, just buggy code (was: related to Spinlock imp... by asdfasgasdgasdg on Sunday January 05, 2020 @12:24PM (#21962405)
> Writing this way doesn't "streamline" anything.

Exactly. Blameless and non-violent language can streamline communication. It does this by removing any trigger that would make your communication partner feel defensive. Needlessly emotional and charged language is sure to distract from the subject at hand. When you use calm language, there is only one thing to focus on: the content. When you call someone's code garbage, there are now two things that that person could focus on -- the content and the tone.

To me, it is completely reasonable that the original author might have made a mistake like this. After all, when he shared his findings it seemed like he had found something interesting to me! Many people on this very site commented positively on his efforts. There is nothing "garbage" about the code that he wrote, it just doesn't quite do exactly what he thought it did.

Re:No nuances, just buggy code (was: related to Spinlock imp... by thezilch on Sunday January 05, 2020 @03:34PM (#21963867)
> To me, it is completely reasonable that the original author might have made a mistake like this. After all, when he shared his findings it seemed like he had found something interesting to me! Many people on this very site commented positively on his efforts. There is nothing "garbage" about the code that he wrote, it just doesn't quite do exactly what he thought it did.

It was blogged about, so carries some authority on the topic, and was convincing to readers, but the code did nothing close -- not just "not quite exactly" -- to what it was portrayed to be doing in the benchmarks or article. It is garbage; useless; should be binned. I tried to come up with better adjectives -- "dangerous", "useless", etc -- but they came up short, in subtle ways. Who cares; Linus explains what he means better than the one, concise word.

Re:No nuances, just buggy code (was: related to Spinlock imp... by sebsito on Sunday January 05, 2020 @02:58PM (#21963612)
Speech is not violence.

It always contains some information payload. If you felt triggered by it and failed to parse the content then maybe you're overly emotional.

For some people who aren't it's going to be useful assessment of how bad this code was.

I see this ongoing trend (Twitter) that by limiting the ways in which people can express themselves, you can in theory broaden the recipient circle (to include people who otherwise would be offended and wouldn't read).

In practice you not only limit the ways in which information can be distributed but often also barter away some people who weren't offended and would get useful information this way.

Looking at speech this way is also a bad idea because today's acceptable is tomorrow's unacceptable word and the only way to allow all information is to allow all speech.

Re:No nuances, just buggy code (was: related to Spinlock imp... by asdfasgasdgasdg on Sunday January 05, 2020 @07:20PM (#21965343)
All I'm saying is that there is a spectrum of ways to communicate about things like this, from "fuck you you piece of shit how dare you put out this garbage code" to "hey, bud, I see what you're trying to do. But there's a mistake here, which I can explain." Linus chose something closer to the left than the right. You can get the same technical ideas across either way, but as you move toward the latter mode of communication you will decrease the number of recipients who have trouble receiving your message because of its negative emotional content.

"maybe you're overly emotional." Feel free to label me however you please. It does not change the fact that if your goal is to communicate ideas efficiently, my way will help you avoid alienating some folks, and has no practical downside.

Re:No nuances, just buggy code (was: related to Spinlock imp... by sebsito on Monday January 06, 2020 @04:22AM (#21967781)
There's a big difference between ugly ad hominem comments and saying that your code is bs.

> and has no practical downside That's the place when we differ in opinion. It has one direct downside of preventing some people from expressing their opinions and conveying the point. And another in the long run – setting up a precedents of what can and cannot be said.

> Feel free to label me however you please It was general note not something directed at you.

Re:No nuances, just buggy code (was: related to Spinlock imp... by ModernMech on Sunday January 05, 2020 @12:10PM (#21962286)
In my group, we call it "shoddy" code. A bit less brash than "garbage" I think.
Re:No nuances, just buggy code (was: related to Spinlock imp... by dahauns on Sunday January 05, 2020 @08:55AM (#21961245)
If you had followed with multiple paragraphs describing in detail as to why the comment is pure garbage, why it has to be called out, offering context, background information and possible alternatives - then you'd have a valid analogue and a basis for debate. Just sayin'.
Re:No nuances, just buggy code (was: related to Spinlock imp... by needs on Sunday January 05, 2020 @06:45AM (#21960848)
Believe it or not, it's one way or another to formulate a critic, and I'm fine with it. However your strongly worded answer lacks arguments, so color me unconvinced.
Re:No nuances, just buggy code (was: related to Spinlock imp... by mda on Sunday January 05, 2020 @06:44AM (#21960847)
Except your attempt is not exactly analogus to the situation discussed.
Re:No nuances, just buggy code (was: related to Spinlock imp... by sebsito on Sunday January 05, 2020 @07:04AM (#21960912)
Critique doesn’t have to be peaceful to be constructive
Re:No nuances, just buggy code (was: related to Spinlock imp... by speedplane on Sunday January 05, 2020 @04:28AM (#21960474)
> As long as Linus is blaming the work done and not the people behind it, that's fine.

Certainly, ad hominem attacks are worse than making substantive attacks, but is that really the standard we should judge it by? Instead of a sprawling thread of visceral, wouldn't it be better if he just explained the reasons why the approach is bad in a professional manner?

Writing like this just seems sloppy and non-professional. It's rambling and unclear. It could have been far more effective if written point-by-point with far less emotion.

Re:No nuances, just buggy code (was: related to Spinlock imp... by xelxebar on Sunday January 05, 2020 @06:41AM (#21960833)
Calling out non-professionalism and bashing a stranger's communication style are, perhaps ironically, nice examples of non-professional behavior.

I would answer your rhetorical questions with an emphatic "no." People's emotions and mental state are important. It's also important that we communicate, understand, and think about people's interior worlds.

Question for you: What else is Linus communicating with his writing style? Does he show that he cares? About what? What can we tell about his values? Are these values we want in a leader?

Sometimes it's good to take off the prescriptivist hat and try on Honest Curiosity.

Re:No nuances, just buggy code (was: related to Spinlock imp... by loopz on Sunday January 05, 2020 @09:35AM (#21961381)
If what you're measuring are random delays due to default scheduling and flawed code implementation, calling it "garbage" should give the author and others pause to think. In some cases, one need to establish a boundary, so as to not waste time and efforts into an endless discussion on flawed premises.

Explaining why and educating about the concepts, is the better approach, and was there as well. Short and concise would be best, while limiting the negative to exactly what need be pointed out: A spade is a spade after all.

If it stops people from developing "their own userspace spinlocks", it may even be kind of necessary to be quite direct.

Re:No nuances, just buggy code (was: related to Spinlock imp... by speedplane on Saturday January 11, 2020 @02:43AM (#22018733)
> Calling out non-professionalism and bashing a stranger's communication style are, perhaps ironically, nice examples of non-professional behavior.

I don't see how this is the case. One can critique a style of communication professionally just like any endeavor. I'm not "bashing" Linus, or even suggesting that he should be less honest. Just that there are far more effective ways to make the same point.

Re:No nuances, just buggy code (was: related to Spinlock imp... by diffeomorphism on Sunday January 05, 2020 @04:50AM (#21960539)
> yet an other entry in the "Linus bullies some poor coder into submission by insulting them until they just stop responding"

Has that ever happened? My impression was that he only ever takes a rough tone with high profile coders and is nice and polite to "poor coders". Also, he never insults them personally, but says that their code/argument is bad and that they are smart enough to know that already. Hence, they should stop making excuses and fix it already.

Re:No nuances, just buggy code (was: related to Spinlock imp... by simias on Sunday January 05, 2020 @05:02AM (#21960571)
I still think that this tone is counterproductive, but that might be personal preference. I hate working in an environment where I know I can end up on the receiving end of some public humiliation if I voice a dissenting opinion or make a mistake. That's how you end up with people censuring themselves and not pointing out when somebody is actually making a mistake because they don't want to suffer the abuse.

This is especially inexcusable coming from Linus because it's not like he needs to resort to these tactics to be heard or make an impression, he's one of the most respected software devs in existence (and for good reasons). You could remove all the abuse from his posts and you'd lose exactly nothing IMO.

But this discussion is hackneyed, I know many people love Linus' style and think it's perfectly acceptable and even a good thing, I'm just definitely not one of them.

Re:No nuances, just buggy code (was: related to Spinlock imp... by mritun on Sunday January 05, 2020 @09:05PM (#21965822)
Sigh

It’s sad that there are people who think calling garbage code garbage is inappropriate. What goes in their mind? Don’t they smell or call a smell a smell?

Re:No nuances, just buggy code (was: related to Spinlock imp... by TheFlyingFish on Tuesday January 07, 2020 @07:36PM (#21986972)
On at least one memorable occasion [0], he expressed surprise that the developer(s) responsible for some piece of code had survived to adulthood, considering they "were likely too stupid to find a tit to suck on" as a baby. I'm not super aware of the context here, but at first glance it doesn't appear to be a high-profile coder with lots of kernel experience that he's talking about.

[0] https://lkml.org/lkml/2012/7/6/495