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

[Paul E. McKenney]

On Wed, Jul 01, 2015 at 12:12:21PM +0200, Peter Zijlstra wrote:
> On Tue, Jun 30, 2015 at 08:37:01PM -0700, Paul E. McKenney wrote:
> > > Wait, what?  Why is anything using traditional (non-S) RCU while *any*
> > > lock is held?
> > 
> > In their defense, it is a sleeplock that is never taken except when
> > rearranging networking configuration.  Sometimes they need a grace period
> > under the lock.  So synchronize_net() checks to see if RTNL is held, and
> > does a synchronize_rcu_expedited() if so and a synchronize_rcu() if not.
> 
> Sounds vile.

OK, I'll bite.  Exactly what seems especially vile about it?

							Thanx, Paul

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/