Re: call_rcu from trace_preempt

Paul E. McKenney
2015-06-16T16:07:30Z

On Tue, Jun 16, 2015 at 11:43:42AM -0400, Steven Rostedt wrote:
> On Tue, 16 Jun 2015 07:16:26 -0700
> "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> wrote:
>
> > > Just for the record: Using a thread for freeing the memory is curing the
> > > problem without the need to modify rcu_is_watching.
> >
> > I must confess to liking this approach better than guaranteeing full-up
> > reentrancy in call_rcu() and kfree_rcu(). ;-)
>
> Then reentrancy must be really bad if you prefer a spinning thread that
> polls constantly just to free an item ;-)

I was (perhaps naively) assuming that they would use a less aggressive
approach at some point. ;-)

Thanx, Paul