Re: [PATCH RFC 0/3] Improve stability of system clock

From: Rusty Russell
Date: Sun May 21 2017 - 20:34:00 EST


John Stultz <john.stultz@xxxxxxxxxx> writes:
> On Wed, May 17, 2017 at 9:54 PM, Richard Cochran
> <richardcochran@xxxxxxxxx> wrote:
>> On Wed, May 17, 2017 at 04:06:07PM -0700, John Stultz wrote:
>>> On Wed, May 17, 2017 at 10:22 AM, Miroslav Lichvar <mlichvar@xxxxxxxxxx> wrote:
>>> > Is there a better way to run the timekeeping code in an userspace
>>> > application? I suspect it would need something like the Linux Kernel
>>> > Library project.
>>>
>>> I dunno. There's probably a cleaner way to go about it, but I also
>>> feel like the benefit of just having the test in the kernel tree is
>>> that it can be managed as a unified whole, rather then the test being
>>> a separate thing and always playing catchup to kernel changes.
>>
>> I vaguely recall a rant on the list years ago from a Linux bigwhig
>> saying how we don't support that kind of thing. But maybe it is my
>> imagination. In any case, IMHO running user space tests for chunks of
>> kernel code can be quite useful.
>
> So a few years ago I mentioned this at a testing session at I think
> Linux Plubmers' and Rusty (CC'ed) commented that he had some netfilter
> (or iptables?) simulator code that never made it upstream. However,
> now that kselftests are integrated with the kernel this could change.
> At least that's my memory of the discussion.

Yep, we did it with nfsim, but forward porting was a PITA. Good luck!

Rusty.