net: add netdev_upper_get_next_dev_rcu(dev, iter)
net: add netdev_upper_get_next_dev_rcu(dev, iter)

This function returns the next dev in the dev->upper_dev_list after the
struct list_head **iter position, and updates *iter accordingly. Returns
NULL if there are no devices left.

Caller must hold RCU read lock.

CC: "David S. Miller" <fe08d3c717adf2ae63592e4c9aec6e3e404d8e3e@davemloft.net>
CC: Eric Dumazet <312c7d941f03386814be517ffdb3e0eb6624e275@google.com>
CC: Jiri Pirko <1b548d10035ae428195c41f5d55eedb1437ccd8a@resnulli.us>
CC: Alexander Duyck <af56634f9be8457194a3461ec96c497f138af4ff@intel.com>
CC: Cong Wang <b08afa93ec8eabe95bc97d12956ca699fa65834c@redhat.com>
Signed-off-by: Veaceslav Falico <13e4c2c2c15eff98ad47d02f3ccee2d83dc7015d@redhat.com>
Signed-off-by: David S. Miller <fe08d3c717adf2ae63592e4c9aec6e3e404d8e3e@davemloft.net>

KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs