Re: [RFC PATCH v9 for 4.15 01/14] Restartable sequences system call

[Linus Torvalds <torvalds@linux-foundation.org>]

On Fri, Oct 13, 2017 at 1:54 PM, Paul E. McKenney
<paulmck@linux.vnet.ibm.com> wrote:
>>
>> And if nobody can be bothered to write the user-level code and test
>> this patch-series, then obviously it's not important enough for the
>> kernel to merge it.
>
> My guess is that it will take some time, probably measured in months,
> to carry out this level of integration and testing to.

That would be an argument if this was a new patch series. "Wait a few months".

But that just isn't the case here.

The fact is, these patches have been floating around in one form or
another not for a couple of months, but for years. There's a LWN
article about it from 2015, and it wasn't new back then either (slides
from 2013).

I wouldn't be surprised if there had been academic _papers_ written
about the notion.

So if there  *still* is no actual real code around this, then that
just strengthens my point - no way should we merge something where
people haven't actually bothered to write the user-mode component for
years and years.

It really boils down to: "if nobody can be bothered to write the user
mode parts after several years, why should it be merged into the
kernel"?

I don't think that's too much to ask for.

                Linus