Re: [PATCH 0/2] nohz: Deal with clock reprogram skipping issues v3

From: Ingo Molnar
Date: Tue May 23 2017 - 03:25:33 EST



* Frederic Weisbecker <fweisbec@xxxxxxxxx> wrote:

> v2 had issues on -tip tree and triggered a warning. It seems to have
> disappeared. Perhaps it was due to another timer issue. Anyway this
> version brings more debugging informations, with a layout that is more
> bisection-friendly and it also handles ticks that fire outside IRQ
> context and thus carry NULL irq regs. This happen when
> hrtimer_interrupt() is called on hotplug cpu down for example.
>
> We'll see if the issue arises again.
>
> git://git.kernel.org/pub/scm/linux/kernel/git/frederic/linux-dynticks.git
> nohz/fixes
>
> HEAD: cd15f46b284f04dbedd065a9d99a4e0badae379a
>
> Thanks,
> Frederic
> ---
>
> Frederic Weisbecker (2):
> nohz: Add hrtimer sanity check
> nohz: Fix collision between tick and other hrtimers, again
>
>
> kernel/time/tick-sched.c | 48 +++++++++++++++++++++++++++++++++++++++++++-----
> kernel/time/tick-sched.h | 2 ++
> 2 files changed, 45 insertions(+), 5 deletions(-)

So I think the 3 commits queued up right now:

99fa871820cf: nohz: Reset next_tick cache even when the timer has no regs
411fe24e6b7c: nohz: Fix collision between tick and other hrtimers, again
ce6cf9a15d62: nohz: Add hrtimer sanity check

are OK and I'd not rebase them unless there's some breakage.

One thing I noticed: your second series does appear to have:

99fa871820cf: nohz: Reset next_tick cache even when the timer has no regs

is that intentional? That is pretty much the only commit I'd love to rebase with a
proper description added.

Thanks,

Ingo