Re: [PATCH] mac80211: retry sending failed BAR frames later instead of tearing down aggr

[Felix Fietkau <nbd@openwrt.org>]

On 2011-08-29 8:58 AM, Helmut Schaa wrote:
> On Sun, Aug 28, 2011 at 9:11 PM, Felix Fietkau<nbd@openwrt.org>  wrote:
>>  Unfortunately failed BAR tx attempts happen more frequently than I
>>  expected, and the resulting aggregation teardowns cause performance
>>  issues, as the aggregation session does not always get re-established
>>  properly.
>>  Instead of tearing down the entire aggr session, we can simply store the
>>  SSN of the last failed BAR tx attempt, wait for the first successful
>>  tx status event, and then send another BAR with the same SSN.
>>
>>  Signed-off-by: Felix Fietkau<nbd@openwrt.org>
>>  Cc: Helmut Schaa<helmut.schaa@googlemail.com>
>
> [...]
>
>>    static void ieee80211_frame_acked(struct sta_info *sta, struct sk_buff *skb)
>>    {
>>          struct ieee80211_mgmt *mgmt = (void *) skb->data;
>>          struct ieee80211_local *local = sta->local;
>>          struct ieee80211_sub_if_data *sdata = sta->sdata;
>>
>>  +       if (ieee80211_is_data_qos(mgmt->frame_control)) {
>>  +               struct ieee80211_hdr *hdr = (void *) skb->data;
>>  +               u8 *qc = ieee80211_get_qos_ctl(hdr);
>>  +               u16 tid = qc[0]&  0xf;
>>  +
>>  +               ieee80211_check_pending_bar(sta, hdr->addr1, tid);
>>  +       }
>>  +
>
> This code will not be run for injected QoS frames. Is this intended?
> Otherwise looks good to me.
I didn't consider it, but I think it's fine. I don't expect any 
aggregated injected traffic under normal circumstances anyway.

- Felix