[PATCH 1/2] supplicant: Use high-priority queue for management packets.

[Johannes Berg]

On Wed, 2014-01-15 at 09:18 -0800, Ben Greear wrote:

> > Now, I'm not necessarily saying this would be a bad thing, but as it
> > stands right now I'm not convinced that this can be done.
> 
> I'm not trying to force a driver to do anything, but I would definitely
> like to suggest a driver give the management packets high priority,
> and for drivers I can use and modify, I will try to make sure they work
> properly.  Other driver writers can do as they wish.

Sure, that's all well, I guess I'm just a bit worried that other drivers
might interpret those priority values of 256+ as different specials, and
the wrong thing would happen if this change was done generically in
wpa_s.

> If anyone can proclaim an API, then you can.  If you have another API in mind,
> please detail it.  If no one cares, then I can just carry the hostap patch in
> my own tree and move on to other things.

The obvious other alternative would be to just do this in the kernel,
assigning high priority to any packets that have
tx->sdata->control_port_protocol == tx->skb->protocol (speaking in
mac80211 language) - a number of drivers already do some special things
via IEEE80211_TX_CTRL_PORT_CTRL_PROTO.

I'm not entirely sure that's a better solution overall, but in terms of
driver compatibility it would certainly be less risky.

johannes