Re: [patch 00/18] CFS Bandwidth Control v7.2

Peter Zijlstra
2011-07-25T16:28:55Z

On Mon, 2011-07-25 at 09:21 -0700, Paul E. McKenney wrote:
> On Mon, Jul 25, 2011 at 05:00:41PM +0200, Peter Zijlstra wrote:
> > On Mon, 2011-07-25 at 16:58 +0200, Peter Zijlstra wrote:
> > > + rcu_read_lock();
> > > + ret = walk_tg_tree_from(tg, tg_set_cfs_period_down, NULL, &period);
> > > + rcu_read_unlock();
> >
> > rcu over a mutex doesn't really work in mainline, bah..
>
> SRCU can handle that situation, FWIW. But yes, blocking in an RCU
> read-side critical section is a no-no.

Yeah, I know, but didn't notice until after I sent.. SRCU isn't useful
though, way too slow due to lacking srcu_call().