On Sat, Oct 12, 2013 at 07:43:54PM +0200, Hannes Frederic Sowa wrote: > On Sat, Oct 12, 2013 at 07:39:30PM +0200, Hannes Frederic Sowa wrote: > > On Sat, Oct 12, 2013 at 10:13:45AM -0700, Paul E. McKenney wrote: > > > On Fri, Oct 11, 2013 at 11:53:27PM -0700, Josh Triplett wrote: > > > > On Fri, Oct 11, 2013 at 04:16:59PM -0700, Paul E. McKenney wrote: > > > > > Changes from v2: > > > > > > > > > > o Switch from rcu_assign_pointer() to ACCESS_ONCE() given that > > > > > the pointers are all --rcu and already visible to readers, > > > > > as suggested by Eric Dumazet and Josh Triplett. > > > > > > > > Hang on a moment. Do *none* of these cases need write memory barriers? > > > > > > Sigh. Some afternoons it doesn't pay to touch the keyboard. > > > > > > Thank you for catching this. I will fix, but at this point, I am thinking > > > in terms of 3.14 rather than 3.13 for this series. > > > > Some of them looked safe. You could also replace --rcu with __rcu in the > > comments while at it. > > Most of them deal with management, maybe a rtnl_assign_pointer with lockdep > check for rtnl lock could help to not clean up the wrong bits. > > I don't know if rtnl_assign_pointer is that a could name as it does not really > explain why the barrier is not needed there. :/ Beyond a certain point, I need to let people who know more about Linux's networking implementation handle this sort of thing. Thanx, Paul
