Hi, For now, yes, you have to assume that you won't always get a response for a rate lookup. The buffer may be sent with NOACK set, it may be deleted during a channel change or scan, etc.
And yes - the rate control lookup stuff for aggregate frames is a bit messy. It would be nice for the rate control code to return the rate _and_ the maximum aggregate size, in case the aggregation selection wants to cap how long frames are at the given choice. -adrian On 11 September 2013 10:29, Chenchong Qin <[email protected]> wrote: > Hi! > > I've added some aggregation support here! > > At first I intend to pass subframe informations(nframes, per-subframe > length etc.) > to the ratectl api. But it seems to be a paradox that rate lookup must be > performed > before the ampdu is formed (aggregation limit based on the rate control > decision > is need) and subframe informations can be obtain only after the ampdu is > formed. > So, I add a new ieee80211_rc_info flag to ieee80211_ratectl to let it > distinguish > aggregation and non-aggregation scenarios. If rate lookup is called in an > aggregation > scenario, this flag is set. Then, ratectl algo knows that it's now finding > rates for an > ampdu and the framelen which records len of the first frame can be > ignored. When > it comes to complete period, tx status that shows number of subframes been > sent > and number of subframes been successfully received is passed to the > ratectl api. > > I also get a question here - whether one tx that doesn't perform rate > lookup will call > the complete procedure? > > Thanks! > > Chenchong > > > On Sun, Sep 8, 2013 at 11:18 PM, Chenchong Qin <[email protected]>wrote: > >> Hi! >> >> I've added the common ratectl state as an mbuf tag! >> >> After days of frustration (compile errors, boot failed, kernel panics, >> suddenly kernel freezing...), it seems that ath now can use 11n-aware >> net80211 ratectl api to do rate control. Attachment[0] is the diff of >> modifications to dev/ath. Changes to net80211 is minor this time. Just add >> some debug msgs to it. Please reference my gsoc svn >> repo<https://svnweb.freebsd.org/socsvn/soc2013/ccqin/head/> >> . >> >> It's worth mentioning that sometimes the kernel will "freezing" (it looks >> like all things stop working, screen is freezing, keyboard and mouse are >> not responding) after wireless stuff start working for a while. At first, I >> consider it caused by my modification to ath. But this strange thing can >> also happen in a head kernel (r255382). Attachment[1] is some useful >> messages just before it happens. By the way, I use a AR9227 device. >> >> And, I found that, for aggregation scenario, ath gathers tx information >> and update the ratectl states. So, what we can do to net80211 to let it >> support aggregation? >> >> Thanks! >> >> Chenchong >> >> >> On Tue, Sep 3, 2013 at 9:29 AM, Chenchong Qin <[email protected]>wrote: >> >>> OK! >>> >>> Thanks! :-) >>> >>> Chenchong >>> >>> >>> On Tue, Sep 3, 2013 at 1:56 AM, Adrian Chadd <[email protected]> wrote: >>> >>>> Hi! >>>> >>>> You can declare an mbuf tag and use that. Look at M_TXCB in net80211 >>>> and how mbuf tags are added. >>>> >>>> I've long thought about adding a net80211 mbuf tag to represent -all- >>>> of the tx related state - TX callback, rate control, rate completion, >>>> aggregation state, retry count, etc. That way all the drivers can use it. >>>> >>>> >>>> >>>> -adrian >>>> >>>> >>> >> > _______________________________________________ [email protected] mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-wireless To unsubscribe, send any mail to "[email protected]"
