netdev-bsd: Fix tx/rx stats for type=tap netdev

Signed-off-by: YAMAMOTO Takashi <yamamoto@valinux.co.jp>
Signed-off-by: Ben Pfaff <blp@nicira.com>
ofproto-dpif.at: Avoid races in "ofproto-dpif - dummy interface"

Signed-off-by: YAMAMOTO Takashi <yamamoto@valinux.co.jp>
Signed-off-by: Ben Pfaff <blp@nicira.com>
Always insert MPLS labels after VLAN tags.

OpenFlow 1.1 and 1.2 always inserted MPLS labels after VLAN tags.
OpenFlow 1.3 and 1.4 insert MPLS labels before VLAN tags.
OpenFlow 1.3.4 and 1.5, both in preparation, recognize that the change in
1.3 was an error and revert it.  This commit implements that reversion
in Open vSwitch.

EXT-457.
Signed-off-by: Ben Pfaff <blp@nicira.com>
Acked-by: Simon Horman <horms@verge.net.au>
tests: Add MPLS + VLAN tests.

Originally part of "odp: Allow VLAN actions after MPLS actions"
by Joe Stringer.

Co-authored-by: Joe Stringer <joestringer@nicira.com>
Signed-off-by: Simon Horman <horms@verge.net.au>
Signed-off-by: Ben Pfaff <blp@nicira.com>
FAQ: Describe the state of MPLS in Open vSwitch.

Signed-off-by: Ben Pfaff <blp@nicira.com>
Acked-by: Simon Horman <horms@verge.net.au>
FAQ: Correct typo.

Reported-by: Pasi Kärkkäinen <pasik@iki.fi>
Signed-off-by: Ben Pfaff <blp@nicira.com>
ovs-thread: Add a comment.

Reported-by: YAMAMOTO Takashi <yamamoto@valinux.co.jp>
Signed-off-by: Ben Pfaff <blp@nicira.com>
collectors: Improve log message to better describe errors.

Signed-off-by: Ben Pfaff <blp@nicira.com>