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

From	John Stultz <john.stultz@linaro.org>
Newsgroups	linux.kernel
Subject	Re: [PATCH RFC 0/3] Improve stability of system clock
Date	2017-05-18 01:10 +0200
Message-ID	<tIgeR-187-9@gated-at.bofh.it> (permalink)
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On Wed, May 17, 2017 at 10:22 AM, Miroslav Lichvar <mlichvar@redhat.com> wrote:
> On Wed, May 17, 2017 at 10:02:00AM -0700, John Stultz wrote:
>> On Wed, May 17, 2017 at 9:57 AM, Miroslav Lichvar <mlichvar@redhat.com> wrote:
>> > On Wed, May 17, 2017 at 09:30:31AM -0700, John Stultz wrote:
>> >> Could you submit your linux-tktest infrastructure to the kselftests dir?
>> >
>> > I can, but it's a mess that breaks frequently as the timekeeping and
>> > other kernel code changes. Are you sure you want that in the kernel
>> > tree? :)
>>
>> Being a mess is a slight concern, but as for breaking, if its
>> in-kernel, then folks can't make changes that break it, right?
>
> It duplicates/stubs quite a few kernel functions that are needed to
> compile and link the timekeeping.c file into an executable. See
> linux-tktest/missing.c. If their signature changes, or new functions
> are needed, it will break.

Hopefully we can fix it in the kernel as well then?

Or maybe it will help inform how we could refactor the time code to
better support the simulation code?

> 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.

thanks
-john

Thread

[PATCH RFC 0/3] Improve stability of system clock Miroslav Lichvar <mlichvar@redhat.com> - 2017-05-17 18:20 +0200
  [PATCH RFC 1/3] timekeeping: Remove support for old vsyscalls Miroslav Lichvar <mlichvar@redhat.com> - 2017-05-17 18:20 +0200
  [PATCH RFC 2/3] timekeeping: Don't align frequency adjustments to ticks Miroslav Lichvar <mlichvar@redhat.com> - 2017-05-17 18:20 +0200
  Re: [PATCH RFC 0/3] Improve stability of system clock John Stultz <john.stultz@linaro.org> - 2017-05-17 18:40 +0200
    Re: [PATCH RFC 0/3] Improve stability of system clock John Stultz <john.stultz@linaro.org> - 2017-05-17 19:10 +0200
      Re: [PATCH RFC 0/3] Improve stability of system clock Miroslav Lichvar <mlichvar@redhat.com> - 2017-05-17 19:30 +0200
        Re: [PATCH RFC 0/3] Improve stability of system clock John Stultz <john.stultz@linaro.org> - 2017-05-18 01:10 +0200
          Re: [PATCH RFC 0/3] Improve stability of system clock Richard Cochran <richardcochran@gmail.com> - 2017-05-18 07:00 +0200
            Re: [PATCH RFC 0/3] Improve stability of system clock John Stultz <john.stultz@linaro.org> - 2017-05-20 02:40 +0200
              Re: [PATCH RFC 0/3] Improve stability of system clock Rusty Russell <rusty@rustcorp.com.au> - 2017-05-22 02:40 +0200
    Re: [PATCH RFC 0/3] Improve stability of system clock Miroslav Lichvar <mlichvar@redhat.com> - 2017-05-17 19:10 +0200

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