On Fri, Jan 28, 2022 at 08:15:47AM -0800, Paul E. McKenney wrote:
> On Fri, Jan 28, 2022 at 04:11:57PM +, Mark Rutland wrote:
> > On Fri, Jan 28, 2022 at 05:08:48PM +0100, Sven Schnelle wrote:
> > > Hi Mark,
> > >
> > > Mark Rutland writes:
> > >
> > > > On arm64 I bisected this down to:
> >
Hi Mark,
Mark Rutland writes:
> On Fri, Jan 28, 2022 at 05:08:48PM +0100, Sven Schnelle wrote:
>> We noticed the PR from Paul and are currently testing the fix. So far
>> it's looking good. The configuration where we have seen the hang is a
>> bit unusual:
>>
>> - 16 physical CPUs on the kvm ho
On Fri, Jan 28, 2022 at 04:11:57PM +, Mark Rutland wrote:
> On Fri, Jan 28, 2022 at 05:08:48PM +0100, Sven Schnelle wrote:
> > Hi Mark,
> >
> > Mark Rutland writes:
> >
> > > On arm64 I bisected this down to:
> > >
> > > 7a30871b6a27de1a ("rcu-tasks: Introduce ->percpu_enqueue_shift for
>
On Fri, Jan 28, 2022 at 05:08:48PM +0100, Sven Schnelle wrote:
> Hi Mark,
>
> Mark Rutland writes:
>
> > On arm64 I bisected this down to:
> >
> > 7a30871b6a27de1a ("rcu-tasks: Introduce ->percpu_enqueue_shift for
> > dynamic queue selection")
> >
> > Which was going wrong because ilog2() rou
Hi Mark,
Mark Rutland writes:
> On arm64 I bisected this down to:
>
> 7a30871b6a27de1a ("rcu-tasks: Introduce ->percpu_enqueue_shift for dynamic
> queue selection")
>
> Which was going wrong because ilog2() rounds down, and so the shift was wrong
> for any nr_cpus that was not a power-of-two.
Hi Sven,
On Thu, Jan 27, 2022 at 07:42:35PM +0100, Sven Schnelle wrote:
> Mark Rutland writes:
>
> > * I intermittently see a hang when running the tests. I previously hit that
> > when originally trying to bisect this issue (and IIRC that bisected down
> > to
> > some RCU changes, but I ne
Hi Mark,
Mark Rutland writes:
> * I intermittently see a hang when running the tests. I previously hit that
> when originally trying to bisect this issue (and IIRC that bisected down to
> some RCU changes, but I need to re-run that). When the tests hang I
> magic-srsrq + L tells me:
>
>
