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Implement mechanism to wait on any of several futexes

lkml.org

21–30 of 158 posts

Re: Implement mechanism to wait on any of several futexes

#21

The specific proposal (linked to from the article) is https://lkml.org/lkml/2019/7/30/1399

Depressing to see reviewers waste review bandwidth bringing up issues such as "wasted newline" and "incorrect comment format". Do kernel developers not use auto-formatters?

Patch submitter should use checkpatch, which will warn about many of these issues.

Re: Implement mechanism to wait on any of several futexes

#22

The specific proposal (linked to from the article) is https://lkml.org/lkml/2019/7/30/1399

Depressing to see reviewers waste review bandwidth bringing up issues such as "wasted newline" and "incorrect comment format". Do kernel developers not use auto-formatters?

On the contrary, I think the feedback provided was excellent and far better than just saying “Doesn’t conform to our style guidelines, please try again”. Bravo Peter.

This may be someone’s first submission and they may consequently not be aware of style guides, tools which can help lint, etc?

Re: Implement mechanism to wait on any of several futexes

#23
post #20
post #15

Earlier quoted context omitted.

Would it be useful to native programs?

Valve's post suggests that they believe this to be the case, although they didn't explain the specific details. > We think that if this feature (or an equivalent) was adopted upstream, we would achieve efficiency gains by adopting it in native massively-threaded applications such as Steam and the Source 2 engine.

I got that. I intended to go for "actually useful".

Re: Implement mechanism to wait on any of several futexes

#24
post #22

Earlier quoted context omitted.

Depressing to see reviewers waste review bandwidth bringing up issues such as "wasted newline" and "incorrect comment format". Do kernel developers not use auto-formatters?

On the contrary, I think the feedback provided was excellent and far better than just saying “Doesn’t conform to our style guidelines, please try again”. Bravo Peter. This may be someone’s first submission and they may consequently not be aware of style guides, tools which can help lint, etc?

Agreed. Also "missing {}" is a super important "style" comment.

Re: Implement mechanism to wait on any of several futexes

#25

Earlier quoted context omitted.

The thing to remember is that version numbers aren’t decimals. They’re two or three integers separated by periods. 11 is higher than 2.

Harumph. Then it should be padded with zeros. So, 4.002 and 4.011 /grumpy edit: nope, it's fine as is. my experience in frame numbers, dates, and so forth do not scale to releases

4.0.0 (semver) and 4.0.0.0 (Windows) aren't valid numbers anyways; The confusion can only arise on X.Y version numbers. Just add a .0 at the end of those

Re: Implement mechanism to wait on any of several futexes

#26
post #6
post #5

Am I interpreting the graph on their page all wrong? It looks like the older version of Proton provides better performance? Unless they're graphing function call return time? The graph and the text around it doesn't do a good job of explaining that.

4.11 is newer than 4.2

I have no idea why this took me so long to realize. Must be the versions I'm used to seeing but my brain parsed `4.11` as `4.1.1`. Weird.

Thanks for pointing out the obvious for those of us who missed it!

Re: Implement mechanism to wait on any of several futexes

#27

The specific proposal (linked to from the article) is https://lkml.org/lkml/2019/7/30/1399

Depressing to see reviewers waste review bandwidth bringing up issues such as "wasted newline" and "incorrect comment format". Do kernel developers not use auto-formatters?

In a project like the kernel consistent style is important and the kernel has tools (Coccinelle spatches, checkpatch.pl) to help developers comply with it. There are standards that need to be followed and the bar is the same for everyone.

Re: Implement mechanism to wait on any of several futexes

#28
post #3

The scale goes from 0 to 80. It's not horribly misleading, but just saying

I believe that’s because it’s frames per second, not an abstract percentile.

While I was able to intuit the the Y axis was FPS, it's not wholly obvious. Labeling the graph (or at the very least, just that axis) would help.

Re: Implement mechanism to wait on any of several futexes

#29
This looks to me like the main change is to make it easier to create mutexes with timeouts.

Isn’t a mutex timing out an indication that:

a) a lock wasn’t needed in the first place or

b) the program is incorrect?

It feels more like they just want the api to match win32 better but most of the multithreaded programming I’ve done lately has just used go’s channels so I totally could be missing something.

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