Re: [PATCH 00/36] cputime: Convert core use of cputime_t to nsecs

From: Frederic Weisbecker
Date: Mon Nov 21 2016 - 11:22:28 EST

On Mon, Nov 21, 2016 at 10:49:23AM +0100, Ingo Molnar wrote:
> * Frederic Weisbecker <fweisbec@xxxxxxxxx> wrote:
> > > But I am still not happy about the approach. What is the compelling reason for
> > > this change except for the "but it looks ugly"?
> >
> > The diffstat (600 lines removed). Also the fact that we have all these
> > workarounds in the core code just for the special case of 1 arch (s390) and a
> > half (powerpc with CONFIG_VIRT_CPU_ACCOUNTING_NATIVE).
> >
> > I'd much rather have all that complexity moved in a vtime_native.c shared by
> > s390 and powerpc that takes care of proper accumulation in cputime_t and flushes
> > that on ticks in nsecs rather than having all these cputime_t game all over the
> > kernel.
> I agree - we really want to concentrate complexity in such a fashion and generally
> standardize on nanosecs, and the diffstat of the patchset is really nice.

Yeah, although the diffstat might become less impressive after the accumulator code,
but still worth it I think.

> The patchset obviously has to build (and work!) on s390/powerpc properly.

Of course!