In netdev_remove, the netdev is unreffed after being removed from the global shash. If the ref count is 0, the netdev is destroyed.
I'll re-submit with a more accurate comment for netdev_remove (it unrefs rather than destroys the netdev) and also adding a comment with netdev_remove in iface_destroy__ (which Alex recommended). ----- Original Message ----- From: "Ben Pfaff" <b...@nicira.com> To: "Ryan Wilson" <wr...@nicira.com> Cc: dev@openvswitch.org Sent: Friday, May 16, 2014 7:52:19 AM Subject: Re: [ovs-dev] [PATCH] netdev: Remove netdev from global shash when the user is changing interface configuration. On Thu, May 15, 2014 at 03:01:19AM -0700, Ryan Wilson wrote: > When the user changes port type (i.e. changing p0 from type 'internal' to > 'gre'), the netdev must first be deleted, then re-created with the new type. > Deleting the netdev requires there exist no more references to the netdev. > However, the xlate cache holds references to netdevs and the cache is only > invalidated by revalidator threads. Thus, if cache is not invalidated prior to > the netdev being re-created, the netdev will not be able to be re-created and > the configuration change will fail. > > This patch always removes the netdev from the global netdev shash when the > user changes port type. This ensures that the new netdev can always be created > while handler and revalidator threads can retain references to the old netdev > until they are finished. I think that the comment on netdev_remove() is not entirely correct: I don't see anything in the function that "destroys 'netdev' if possible." Acked-by: Ben Pfaff <b...@nicira.com> _______________________________________________ dev mailing list dev@openvswitch.org http://openvswitch.org/mailman/listinfo/dev
