On Tue, 30 Jan 2018, Linus Torvalds wrote:
> On Mon, Jan 29, 2018 at 10:30 PM, Ingo Molnar <[email protected]> wrote:
> >
> > These are in cases significant driver simplifications, but they also enable
> > the
> > real deal, the elimination of the hrtimer tasklet:
> >
> > softirq: Remove tasklet_hrtimer
> >
> > include/linux/interrupt.h | 25 -----------------------
> > kernel/softirq.c | 51
> > -----------------------------------------------
> > 2 files changed, 76 deletions(-)
> >
> > ... which is a pretty nice thing in itself even without the driver
> > simplifications!
> >
> > Plus the _real_ secret motivation behind it all is the -rt kernel and
> > CONFIG_PREEMPT_RT=y and the ability to push most of the hrtimer processing
> > into
> > softirq context - while it still keeps the main hrtimer machinery capable
> > to run
> > in hard-RT hardirq domain. Turns out it was possible to implement this
> > duality via
> > the softirq-hrtimers, with a good chunk of benefits to non-rt upstream as
> > well.
>
> So this is the kind of explanation that I would have liked in the
> "please pull" (and that would have been great in the merge message).
> Explaining not just the "what", but very much the "why".
>
> Anyway, it's obviously pulled regardless, and I'm just pointing this
> out for "maybe next time".
Sorry about that. I usually try to be descriptive and will do so next time
again.
Thanks,
tglx
