Re: [PATCH v2 4/4] clock: add perf_clock posix clock

Ingo Molnar
2015-02-18T18:22:48Z

* John Stultz <john.stultz@linaro.org> wrote:

> > AFAIK Stephane is not proposing this patch for
> > inclusion but rather it is an unfortunate necessary
> > evil. The module exposes perf_clock (ie., local_clock)
> > to userspace and allows in this case the generation of
> > samples with a perf timestamp which is required for
> > proper sorting.
> >
> > I understand this solution is not liked, but it works,
> > requires no kernel modifications to achieve the end
> > goal and can be used for kernels going back to at least
> > 2.6.38 (perhaps earlier, have not checked).
>
> Yep. And I'm sympathetic to the fact that an alternative
> solution hasn't made it upstream yet. I'm hopeful Pawel's
> recent approach will make it in (it seems like it hasn't
> raised any flags w/ scheduler folks - but I've not always
> been able to follow the discussion closely).

So if it's part of this series and reviews fine then I'll
be happy to apply it! Nothing better than having a kernel
patch and an actual usecase go hand in hand.

Thanks,

Ingo