Author: adrian
Date: Fri Jun 17 11:13:37 2011
New Revision: 223184
URL: http://svn.freebsd.org/changeset/base/223184
Log:
This is a very very dirty hack to stuff ADDBA frames into the correct
destination TXQ.
From the code:
* ADDBA (and potentially others) need to be placed in the same
* hardware queue as the TID/node it's relating to. This is so
* it goes out after any pending non-aggregate frames to the
* same node/TID.
*
* If this isn't done, the ADDBA can go out before the frames
* queued in hardware. Even though these frames have a sequence
* number -earlier- than the ADDBA can be transmitted (but
* no frames whose sequence numbers are after the ADDBA should
* be!) they'll arrive after the ADDBA - and the receiving end
* will simply drop them as being out of the BAW.
*
* The frames can't be appended to the TID software queue - it'll
* never be sent out. So these frames have to be directly
* dispatched to the hardware, rather than queued in software.
* So if this function returns true, the TXQ has to be
* overridden and it has to be directly dispatched.
*
* It's a dirty hack, but someone's gotta do it.
Modified:
user/adrian/if_ath_tx/sys/dev/ath/if_ath_tx.c
Modified: user/adrian/if_ath_tx/sys/dev/ath/if_ath_tx.c
==============================================================================
--- user/adrian/if_ath_tx/sys/dev/ath/if_ath_tx.c Fri Jun 17 10:21:24 2011 (r223183)
+++ user/adrian/if_ath_tx/sys/dev/ath/if_ath_tx.c Fri Jun 17 11:13:37 2011 (r223184)
@@ -106,6 +106,8 @@ static int ath_tx_ampdu_running(struct a
int tid);
static ieee80211_seq ath_tx_tid_seqno_assign(struct ath_softc *sc,
struct ieee80211_node *ni, struct ath_buf *bf, struct mbuf *m0);
+static int ath_tx_action_frame_override_queue(struct ath_softc *sc,
+ struct ieee80211_node *ni, struct mbuf *m0, int *tid);
/*
* Whether to use the 11n rate scenario functions or not
@@ -1014,6 +1016,8 @@ ath_tx_raw_start(struct ath_softc *sc, s
struct ath_desc *ds;
u_int pri;
uint8_t try[4], rate[4];
+ int o_tid = -1;
+ int do_override;
bzero(try, sizeof(try));
bzero(rate, sizeof(rate));
@@ -1185,14 +1189,37 @@ ath_tx_raw_start(struct ath_softc *sc, s
/* NB: no buffered multicast in power save support */
+ /* XXX If it's an ADDBA, override the correct queue */
+ do_override = ath_tx_action_frame_override_queue(sc, ni, m0, &o_tid);
+
+ /* Map ADDBA to the correct priority */
+ if (do_override) {
+#if 0
+ device_printf(sc->sc_dev,
+ "%s: overriding tid %d pri %d -> %d\n",
+ __func__, o_tid, pri, TID_TO_WME_AC(o_tid));
+#endif
+ pri = TID_TO_WME_AC(o_tid);
+ }
+
/* Fill in the details in the descriptor list */
ath_tx_chaindesclist(sc, sc->sc_ac2q[pri], bf);
- /* Queue to software queue */
- ath_tx_swq(sc, ni, sc->sc_ac2q[pri], bf, m0);
+ /*
+ * If we're overiding the ADDBA destination, dump directly
+ * into the hardware queue, right after any pending
+ * frames to that node are.
+ */
+
+ if (do_override)
+ ath_tx_handoff(sc, sc->sc_ac2q[pri], bf);
+ else {
+ /* Queue to software queue */
+ ath_tx_swq(sc, ni, sc->sc_ac2q[pri], bf, m0);
- /* Kick txq */
- ath_txq_sched(sc);
+ /* Kick txq */
+ ath_txq_sched(sc);
+ }
return 0;
}
@@ -1261,6 +1288,93 @@ bad:
return error;
}
+/* Some helper functions */
+
+/*
+ * ADDBA (and potentially others) need to be placed in the same
+ * hardware queue as the TID/node it's relating to. This is so
+ * it goes out after any pending non-aggregate frames to the
+ * same node/TID.
+ *
+ * If this isn't done, the ADDBA can go out before the frames
+ * queued in hardware. Even though these frames have a sequence
+ * number -earlier- than the ADDBA can be transmitted (but
+ * no frames whose sequence numbers are after the ADDBA should
+ * be!) they'll arrive after the ADDBA - and the receiving end
+ * will simply drop them as being out of the BAW.
+ *
+ * The frames can't be appended to the TID software queue - it'll
+ * never be sent out. So these frames have to be directly
+ * dispatched to the hardware, rather than queued in software.
+ * So if this function returns true, the TXQ has to be
+ * overridden and it has to be directly dispatched.
+ *
+ * It's a dirty hack, but someone's gotta do it.
+ */
+
+/*
+ * XXX doesn't belong here!
+ */
+static int
+ieee80211_is_action(struct ieee80211_frame *wh)
+{
+ /* Type: Management frame? */
+ if ((wh->i_fc[0] & IEEE80211_FC0_TYPE_MASK) !=
+ IEEE80211_FC0_TYPE_MGT)
+ return 0;
+
+ /* Subtype: Action frame? */
+ if ((wh->i_fc[0] & IEEE80211_FC0_SUBTYPE_MASK) !=
+ IEEE80211_FC0_SUBTYPE_ACTION)
+ return 0;
+
+ return 1;
+}
+
+#define MS(_v, _f) (((_v) & _f) >> _f##_S)
+/*
+ * Return an alternate TID for ADDBA request frames.
+ *
+ * Yes, this likely should be done in the net80211 layer.
+ */
+static int
+ath_tx_action_frame_override_queue(struct ath_softc *sc,
+ struct ieee80211_node *ni,
+ struct mbuf *m0, int *tid)
+{
+ struct ieee80211_frame *wh = mtod(m0, struct ieee80211_frame *);
+ struct ieee80211_action_ba_addbarequest *ia;
+ uint8_t *frm;
+ uint16_t baparamset;
+
+ /* Not action frame? Bail */
+ if (! ieee80211_is_action(wh))
+ return 0;
+
+ /* XXX Not needed for frames we send? */
+#if 0
+ /* Correct length? */
+ if (! ieee80211_parse_action(ni, m))
+ return 0;
+#endif
+
+ /* Extract out action frame */
+ frm = (u_int8_t *)&wh[1];
+ ia = (struct ieee80211_action_ba_addbarequest *) frm;
+
+ /* Not ADDBA? Bail */
+ if (ia->rq_header.ia_category != IEEE80211_ACTION_CAT_BA)
+ return 0;
+ if (ia->rq_header.ia_action != IEEE80211_ACTION_BA_ADDBA_REQUEST)
+ return 0;
+
+ /* Extract TID, return it */
+ baparamset = le16toh(ia->rq_baparamset);
+ *tid = (int) MS(baparamset, IEEE80211_BAPS_TID);
+
+ return 1;
+}
+#undef MS
/* Per-node software queue operations */