Re: [PATCH tip/core/rcu 03/15] rcu: Drive TASKS_RCU directly off of PREEMPT

[Paul E. McKenney]

On Tue, Jul 25, 2017 at 02:14:05PM -0400, Steven Rostedt wrote:
> On Mon, 24 Jul 2017 14:44:32 -0700
> "Paul E. McKenney" <paulmck@xxxxxxxxxxxxxxxxxx> wrote:
> 
> > The actual use of TASKS_RCU is only when PREEMPT, otherwise RCU-sched
> > is used instead.  This commit therefore makes synchronize_rcu_tasks()
> > and call_rcu_tasks() available always, but mapped to synchronize_sched()
> > and call_rcu_sched(), respectively, when !PREEMPT.  This approach also
> > allows some #ifdefs to be removed from rcutorture.
> 
> Hmm, I'll need to update ftrace. I believe I call synchronize_sched()
> twice with !PREEMPT then.

Does this mean that synchronize_rcu_tasks() should invoke
synchronize_sched() twice?  Easy change to make, if so.

							Thanx, Paul