On Mon, Dec 07, 2020 at 02:33:10PM +0100, Stefan Sperling wrote:
> On Mon, Dec 07, 2020 at 01:31:09PM +0100, Tobias Heider wrote:
> > Some APs request a BA agreement and continue to send QOS packets
> > for the same tid (with normal ack policy). Currently, these packets
> > make it to the higher layers without going through BA reordering or the
> > BA buffer. This results in reduced performance later on as the sequence
> > numbers are expected by BA reordering.
> >
> > To fix this, we should use BA agreement immediately after it is
> > requested by the AP. This causes the sequence number counter in
> > the BA agreement to advance for the normal qos packets and the gap
> > wait later on is avoided.
> >
> > ok?
>
> Not yet, see below:
>
Update with comments addressed.
Index: ieee80211_input.c
===================================================================
RCS file: /cvs/src/sys/net80211/ieee80211_input.c,v
retrieving revision 1.221
diff -u -p -r1.221 ieee80211_input.c
--- ieee80211_input.c 28 Aug 2020 12:01:48 -0000 1.221
+++ ieee80211_input.c 7 Dec 2020 14:38:24 -0000
@@ -358,6 +358,17 @@ ieee80211_inputm(struct ifnet *ifp, stru
/* go through A-MPDU reordering */
ieee80211_input_ba(ic, m, ni, tid, rxi, ml);
return; /* don't free m! */
+ } else if (ba_state == IEEE80211_BA_REQUESTED &&
+ (qos & IEEE80211_QOS_ACK_POLICY_MASK) ==
+ IEEE80211_QOS_ACK_POLICY_NORMAL) {
+ /*
+ * Apparently, qos frames for a tid where a
+ * block ack agreement was requested but not
+ * yet confirmed by us should still contribute
+ * to the sequence number for this tid.
+ */
+ ieee80211_input_ba(ic, m, ni, tid, rxi, ml);
+ return; /* don't free m! */
}
}
@@ -2698,6 +2709,9 @@ ieee80211_recv_addba_req(struct ieee8021
ssn = LE_READ_2(&frm[7]) >> 4;
ba = &ni->ni_rx_ba[tid];
+ /* The driver is still processing an ADDBA request for this tid. */
+ if (ba->ba_state == IEEE80211_BA_REQUESTED)
+ return;
/* check if we already have a Block Ack agreement for this RA/TID */
if (ba->ba_state == IEEE80211_BA_AGREED) {
/* XXX should we update the timeout value? */
@@ -2737,7 +2751,7 @@ ieee80211_recv_addba_req(struct ieee8021
goto refuse;
/* setup Block Ack agreement */
- ba->ba_state = IEEE80211_BA_INIT;
+ ba->ba_state = IEEE80211_BA_REQUESTED;
ba->ba_timeout_val = timeout * IEEE80211_DUR_TU;
ba->ba_ni = ni;
ba->ba_token = token;
@@ -2816,6 +2830,7 @@ ieee80211_addba_req_refuse(struct ieee80
free(ba->ba_buf, M_DEVBUF,
IEEE80211_BA_MAX_WINSZ * sizeof(*ba->ba_buf));
ba->ba_buf = NULL;
+ ba->ba_state = IEEE80211_BA_INIT;
/* MLME-ADDBA.response */
IEEE80211_SEND_ACTION(ic, ni, IEEE80211_CATEG_BA,
