openvswitch: refactor do_output() to move NULL check out of fast path
openvswitch: refactor do_output() to move NULL check out of fast path

skb_clone() NULL check is implemented in do_output(), as past of the
common (fast) path. Refactoring so that NULL check is done in the
slow path, immediately after skb_clone() is called.

Besides optimization, this change also improves code readability by
making the skb_clone() NULL check consistent within OVS datapath
module.

Signed-off-by: Andy Zhou <eba59be6f07811efcfb9b9013eddeb3628e492b2@nicira.com>
Signed-off-by: Pravin B Shelar <95dcc1879f3489c0d5163907cdd946775296b2dd@nicira.com>

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