• Johannes Berg's avatar
    mac80211: fix aggregation for hardware with ampdu queues · 96f5e66e
    Johannes Berg authored
    
    
    Hardware with AMPDU queues currently has broken aggregation.
    
    This patch fixes it by making all A-MPDUs go over the regular AC queues,
    but keeping track of the hardware queues in mac80211. As a first rough
    version, it actually stops the AC queue for extended periods of time,
    which can be removed by adding buffering internal to mac80211, but is
    currently not a huge problem because people rarely use multiple TIDs
    that are in the same AC (and iwlwifi currently doesn't operate as AP).
    
    This is a short-term fix, my current medium-term plan, which I hope to
    execute soon as well, but am not sure can finish before .30, looks like
    this:
     1) rework the internal queuing layer in mac80211 that we use for
        fragments if the driver stopped queue in the middle of a fragmented
        frame to be able to queue more frames at once (rather than just a
        single frame with its fragments)
     2) instead of stopping the entire AC queue, queue up the frames in a
        per-station/per-TID queue during aggregation session initiation,
        when the session has come up take all those frames and put them
        onto the queue from 1)
     3) push the ampdu queue layer abstraction this patch introduces in
        mac80211 into the driver, and remove the virtual queue stuff from
        mac80211 again
    
    This plan will probably also affect ath9k in that mac80211 queues the
    frames instead of passing them down, even when there are no ampdu queues.
    Signed-off-by: default avatarJohannes Berg <johannes@sipsolutions.net>
    Signed-off-by: default avatarJohn W. Linville <linville@tuxdriver.com>
    96f5e66e
mac80211.h 74.9 KB