tc: red, gred, tbf: more helpful error messages

$ tc qdisc add dev eth1 root tbf
RTNETLINK answers: Invalid argument

$ tc qdisc add dev eth1 root red
RTNETLINK answers: Invalid argument

with patch:
$ tc qdisc add dev eth1 root red
Required parameter (min, max, burst, limit, avpkt) is missing

$ tc qdisc add dev eth1 root tbf
Usage: ... tbf limit BYTES burst BYTES[/BYTES] rate KBPS ...

Signed-off-by: Florian Westphal <fw@strlen.de>
3 files changed