We set interupt cascading count of outbound queue to get better
performance, correct some unnecessary return values and some noisy
print messages.  patch attached.
Signed-off-by: NJack Wang <jack_wang@usish.com>
Signed-off-by: NLindar Liu <lindar_liu@usish.com>
Signed-off-by: NJames Bottomley <James.Bottomley@suse.de>