Le vendredi 23 décembre 2011 à 18:54 +0100, Dave Taht a écrit :

Are there any place where all 48 bytes of cb are used?

Yes, but on in qdisc layer.

struct tcp_skb_cb is known to be 44 bytes (when IPv6 is enabled)

In qdisc layer, we use a small part of it, for the moment.

I wouldn't mind if 'time_to_send' became a separate skb field
for a more generic 'time_in_queue'...

This wont happen.

As I posted in an earlier patch, this can be added in "struct
qdisc_skb_cb"