Re: Question on vhost_has_feature()

2014-03-05 Thread Michael S. Tsirkin
On Tue, Mar 04, 2014 at 05:01:51PM -0800, Paul E. McKenney wrote: > On Tue, Mar 04, 2014 at 09:56:42AM +0200, Michael S. Tsirkin wrote: > > On Mon, Mar 03, 2014 at 11:44:23AM -0800, Paul E. McKenney wrote: > > > Hello, Michael, > > > > > > Just curious about the purpose of the rcu_dereference_inde

Re: Question on vhost_has_feature()

2014-03-04 Thread Paul E. McKenney
On Tue, Mar 04, 2014 at 09:56:42AM +0200, Michael S. Tsirkin wrote: > On Mon, Mar 03, 2014 at 11:44:23AM -0800, Paul E. McKenney wrote: > > Hello, Michael, > > > > Just curious about the purpose of the rcu_dereference_index_check() in > > vhost_has_feature(). I don't see how it fits in. The clos

Re: Question on vhost_has_feature()

2014-03-03 Thread Michael S. Tsirkin
On Mon, Mar 03, 2014 at 11:44:23AM -0800, Paul E. McKenney wrote: > Hello, Michael, > > Just curious about the purpose of the rcu_dereference_index_check() in > vhost_has_feature(). I don't see how it fits in. The closest thing > I see if the use in handle_rx(), where it selects vq->log or NULL.