Re: [PATCH 0/3] rcu: synchronize_rcu[_expedited]() related fixes

[Frederic Weisbecker]

On Mon, Mar 14, 2022 at 03:35:04PM -0700, Paul E. McKenney wrote:
> On Mon, Mar 14, 2022 at 01:26:10PM -0700, Paul E. McKenney wrote:
> > On Mon, Mar 14, 2022 at 02:37:35PM +0100, Frederic Weisbecker wrote:
> > > 
> > > A few fixes especially for expedited GP polling causing a stall on TREE07,
> > > as reported by Paul.
> > > 
> > > We may still want to optimize start_poll_synchronize_rcu_expedited() on
> > > UP-no-preempt but I think Paul may be implying this while doing other
> > > fixes.
> > > 
> > > git://git.kernel.org/pub/scm/linux/kernel/git/frederic/linux-dynticks.git
> > > 	rcu/dev
> > > 
> > > HEAD: 6e5fd7e614fd5c8f0fffeaa140b7ea697bfeb096
> > > 
> > > Thanks,
> > > 	Frederic
> > 
> > I have pulled these in for review and testing, thank you!!!  I have
> > started a ~90-minute test and will let you know how that goes.
> 
> And TREE05 doesn't like this much.  I get too-short grace periods.
> TREE05 is unusual in being the one with the kernel build with
> CONFIG_PREEMPT_NONE=y but also with CONFIG_PREEMPT_DYNAMIC=n.
> 
> Running tests of the commits individually.

Ouch, please test the following:

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