Re: [PATCH 1/2] cfg80211: initialize rate control after station inserted

Tim Gardner
2009-08-28T21:40:12Z

Johannes Berg wrote:
> Hi Reinette,
>
>> This work is motivated by an attempt to untangle the iwlwifi station
>> management to be able to use mac80211's sta notify callback. From 4965
>> and up the rate scaling in the device is done per station, so an entry
>> in the station table is required for the rate scaling initialization to
>> succeed.
>
> Interesting. I've been thinking about making it go the other way --
> remove rate scaling hooks completely. wl1271 apparently has rate scaling
> completely in the firmware, so the RS algorithm on the host is just
> overhead. I've been thinking putting 4965+ RS into the _driver_ makes
> more sense since it really does a lot in the firmware and not on the
> host.
>
> Do you think we should try to go that route? I'd think it would probably
> be a hardware flag ("no RS algo please") and then we'd skip all the
> hooks and put things into the driver. The advantage is that we don't
> care about the mac80211 API any more, things get cleaner and we can just
> do all RS init from sta_notify().
>

Wouldn't that make it difficult to experiment with external rate scaling
algorithms? Not that minstrel or the other in-driver rate scaling
algorithms always get it right, but they are certainly more transparent
(and changeable) then firmware.

rtg
--
Tim Gardner tim.gardner@canonical.com