Re: [PATCH RFC tip/core/rcu 0/5] Expedited grace periods encouraging normal ones

["Paul E. McKenney" <paulmck@linux.vnet.ibm.com>]

On Thu, Jul 02, 2015 at 04:50:45AM +0200, Mike Galbraith wrote:
> On Wed, 2015-07-01 at 19:18 -0700, Paul E. McKenney wrote:
> 
> > Does their normal workload trigger the condition that results in the
> > expedited grace period?  If so, do they use NO_HZ_FULL?
> 
> They're having no trouble that I'm aware of, and I definitely would be
> made aware.  They're not currently using a kernel with NO_HZ_FULL even
> built in, as that stuff is far far too raw in the current kernel.
> 
> They may meet a NO_HZ_FULL enabled kernel soonish, but will be told to
> not turn it on for anything other than pure compute, as NO_HZ_FULL is
> currently not usable for mixed load in partitioned box, much less rt. 

OK, sounds like synchronize_rcu_expedited() is a complete non-problem
for them, then.

							Thanx, Paul