remove the very basic ath(4) rate control implementation and use

rssadapt(9) instead. this may need some further work but now it's in
the right place and shared with other drivers (like ral(4)).

yes jsg@

2 files changed, 69 insertions, 164 deletions

diff --git a/sys/dev/ic/ath.c b/sys/dev/ic/ath.c
index 879c5de285b..d953cd3f036 100644
--- a/sys/dev/ic/ath.c
+++ b/sys/dev/ic/ath.c
@@ -1,4 +1,4 @@
-/*      $OpenBSD: ath.c,v 1.40 2005/09/19 10:27:08 reyk Exp $  */
+/*      $OpenBSD: ath.c,v 1.41 2005/09/22 10:17:04 reyk Exp $  */
 /*	$NetBSD: ath.c,v 1.37 2004/08/18 21:59:39 dyoung Exp $	*/
 
 /*-
@@ -78,6 +78,7 @@
 #endif
 
 #include <net80211/ieee80211_var.h>
+#include <net80211/ieee80211_rssadapt.h>
 
 #include <dev/pci/pcidevs.h>
 #include <dev/gpio/gpiovar.h>
@@ -134,9 +135,8 @@ int	ath_getchannels(struct ath_softc *, u_int cc, HAL_BOOL outdoor,
 	    HAL_BOOL xchanmode);
 int	ath_rate_setup(struct ath_softc *sc, u_int mode);
 void	ath_setcurmode(struct ath_softc *, enum ieee80211_phymode);
-void	ath_rate_ctl_reset(struct ath_softc *, enum ieee80211_state);
-void	ath_rate_ctl_tx_reset(void *, struct ieee80211_node *);
-void	ath_rate_ctl(void *, struct ieee80211_node *);
+void	ath_rssadapt_updatenode(void *, struct ieee80211_node *);
+void	ath_rssadapt_updatestats(void *);
 void	ath_recv_mgmt(struct ieee80211com *, struct mbuf *,
 	    struct ieee80211_node *, int, int, u_int32_t);
 void	ath_disable(struct ath_softc *);
@@ -294,6 +294,7 @@ ath_attach(u_int16_t devid, struct ath_softc *sc)
 	}
 	timeout_set(&sc->sc_scan_to, ath_next_scan, sc);
 	timeout_set(&sc->sc_cal_to, ath_calibrate, sc);
+	timeout_set(&sc->sc_rssadapt_to, ath_rssadapt_updatestats, sc);
 
 #ifdef __FreeBSD__
 	ATH_TXBUF_LOCK_INIT(sc);
@@ -442,6 +443,10 @@ ath_detach(struct ath_softc *sc, int flags)
 
 	DPRINTF(ATH_DEBUG_ANY, ("%s: if_flags %x\n", __func__, ifp->if_flags));
 
+	timeout_del(&sc->sc_scan_to);
+	timeout_del(&sc->sc_cal_to);
+	timeout_del(&sc->sc_rssadapt_to);
+
 	s = splnet();
 	ath_stop(ifp);
 #if NBPFILTER > 0
@@ -1012,7 +1017,6 @@ void
 ath_watchdog(struct ifnet *ifp)
 {
 	struct ath_softc *sc = ifp->if_softc;
-	struct ieee80211com *ic = &sc->sc_ic;
 
 	ifp->if_timer = 0;
 	if ((ifp->if_flags & IFF_RUNNING) == 0 || sc->sc_invalid)
@@ -1027,17 +1031,7 @@ ath_watchdog(struct ifnet *ifp)
 		}
 		ifp->if_timer = 1;
 	}
-	if (ic->ic_fixed_rate == -1) {
-		/*
-		 * Run the rate control algorithm if we're not
-		 * locked at a fixed rate.
-		 */
-		if (ic->ic_opmode == IEEE80211_M_STA) {
-			ath_rate_ctl(sc, ic->ic_bss);
-		} else {
-			ieee80211_iterate_nodes(ic, ath_rate_ctl, sc);
-		}
-	}
+
 	ieee80211_watchdog(ifp);
 }
 
@@ -2063,7 +2057,11 @@ ath_rx_proc(void *arg, int npending)
 		 * Send frame up for processing.
 		 */
 		ieee80211_input(ifp, m, ni,
-			ds->ds_rxstat.rs_rssi, ds->ds_rxstat.rs_tstamp);
+		    ds->ds_rxstat.rs_rssi, ds->ds_rxstat.rs_tstamp);
+
+		/* Handle the rate adaption */
+		ieee80211_rssadapt_input(ic, ni, &an->an_rssadapt,
+		    ds->ds_rxstat.rs_rssi);
 
 		/*
 		 * The frame may have caused the node to be marked for
@@ -2236,6 +2234,7 @@ ath_tx_start(struct ath_softc *sc, struct ieee80211_node *ni,
 	    bf->bf_dmamap->dm_mapsize, BUS_DMASYNC_PREWRITE);
 	bf->bf_m = m0;
 	bf->bf_node = ni;			/* NB: held reference */
+	an = ATH_NODE(ni);
 
 	/* setup descriptors */
 	ds = bf->bf_desc;
@@ -2246,6 +2245,7 @@ ath_tx_start(struct ath_softc *sc, struct ieee80211_node *ni,
 	 * Calculate Atheros packet type from IEEE80211 packet header
 	 * and setup for rate calculations.
 	 */
+	bf->bf_id.id_node = NULL;
 	atype = HAL_PKT_TYPE_NORMAL;			/* default */
 	switch (wh->i_fc[0] & IEEE80211_FC0_TYPE_MASK) {
 	case IEEE80211_FC0_TYPE_MGT:
@@ -2266,8 +2266,18 @@ ath_tx_start(struct ath_softc *sc, struct ieee80211_node *ni,
 		rix = 0;			/* XXX lowest rate */
 		break;
 	default:
+		/* remember link conditions for rate adaptation algorithm */
+		if (ic->ic_fixed_rate == -1) {
+			bf->bf_id.id_len = m0->m_pkthdr.len;
+			bf->bf_id.id_rateidx = ni->ni_txrate;
+			bf->bf_id.id_node = ni;
+			bf->bf_id.id_rssi = ath_node_getrssi(ic, ni);
+		}
+		ni->ni_txrate = ieee80211_rssadapt_choose(&an->an_rssadapt,
+		    &ni->ni_rates, wh, m0->m_pkthdr.len, ic->ic_fixed_rate,
+		    ifp->if_xname, 0);
 		rix = sc->sc_rixmap[ni->ni_rates.rs_rates[ni->ni_txrate] &
-				IEEE80211_RATE_VAL];
+		    IEEE80211_RATE_VAL];
 		if (rix == 0xff) {
 			printf("%s: bogus xmit rate 0x%x\n", ifp->if_xname,
 				ni->ni_rates.rs_rates[ni->ni_txrate]);
@@ -2277,6 +2287,7 @@ ath_tx_start(struct ath_softc *sc, struct ieee80211_node *ni,
 		}
 		break;
 	}
+
 	/*
 	 * NB: the 802.11 layer marks whether or not we should
 	 * use short preamble based on the current mode and
@@ -2359,7 +2370,6 @@ ath_tx_start(struct ath_softc *sc, struct ieee80211_node *ni,
 	 * initialized to 0 which gives us ``auto'' or the
 	 * ``default'' antenna.
 	 */
-	an = (struct ath_node *) ni;
 	if (an->an_tx_antenna) {
 		antenna = an->an_tx_antenna;
 	} else {
@@ -2500,10 +2510,14 @@ ath_tx_proc(void *arg, int npending)
 		if (ni != NULL) {
 			an = (struct ath_node *) ni;
 			if (ds->ds_txstat.ts_status == 0) {
-				an->an_tx_ok++;
+				if (bf->bf_id.id_node != NULL)
+					ieee80211_rssadapt_raise_rate(ic,
+					    &an->an_rssadapt, &bf->bf_id);
 				an->an_tx_antenna = ds->ds_txstat.ts_antenna;
 			} else {
-				an->an_tx_err++;
+				if (bf->bf_id.id_node != NULL)
+					ieee80211_rssadapt_lower_rate(ic, ni,
+					    &an->an_rssadapt, &bf->bf_id);
 				ifp->if_oerrors++;
 				if (ds->ds_txstat.ts_status & HAL_TXERR_XRETRY)
 					sc->sc_stats.ast_tx_xretries++;
@@ -2517,8 +2531,6 @@ ath_tx_proc(void *arg, int npending)
 			lr = ds->ds_txstat.ts_longretry;
 			sc->sc_stats.ast_tx_shortretry += sr;
 			sc->sc_stats.ast_tx_longretry += lr;
-			if (sr + lr)
-				an->an_tx_retr++;
 			/*
 			 * Reclaim reference to node.
 			 *
@@ -2874,6 +2886,7 @@ ath_newstate(struct ieee80211com *ic, enum ieee80211_state nstate, int arg)
 	ath_ledstate(sc, nstate);
 
 	if (nstate == IEEE80211_S_INIT) {
+		timeout_del(&sc->sc_rssadapt_to);
 		sc->sc_imask &= ~(HAL_INT_SWBA | HAL_INT_BMISS);
 		ath_hal_set_intr(ah, sc->sc_imask);
 		return (*sc->sc_newstate)(ic, nstate, arg);
@@ -2939,10 +2952,6 @@ ath_newstate(struct ieee80211com *ic, enum ieee80211_state nstate, int arg)
 	}
 
 	/*
-	 * Reset the rate control state.
-	 */
-	ath_rate_ctl_reset(sc, nstate);
-	/*
 	 * Invoke the parent method to complete the work.
 	 */
 	error = (*sc->sc_newstate)(ic, nstate, arg);
@@ -2950,6 +2959,9 @@ ath_newstate(struct ieee80211com *ic, enum ieee80211_state nstate, int arg)
 	if (nstate == IEEE80211_S_RUN) {
 		/* start periodic recalibration timer */
 		timeout_add(&sc->sc_cal_to, hz * ath_calinterval);
+
+		if (ic->ic_opmode != IEEE80211_M_MONITOR)
+			timeout_add(&sc->sc_rssadapt_to, hz / 10);
 	} else if (nstate == IEEE80211_S_SCAN) {
 		/* start ap/neighbor scan timer */
 		timeout_add(&sc->sc_scan_to, (hz * ath_dwelltime) / 1000);
@@ -2993,21 +3005,6 @@ ath_newassoc(struct ieee80211com *ic, struct ieee80211_node *ni, int isnew)
 {
 	if (ic->ic_opmode == IEEE80211_M_MONITOR)
 		return;
-
-	if (isnew) {
-		struct ath_node *an = (struct ath_node *) ni;
-
-		an->an_tx_ok = an->an_tx_err =
-			an->an_tx_retr = an->an_tx_upper = 0;
-		/* start with highest negotiated rate */
-		/*
-		 * XXX should do otherwise but only when
-		 * the rate control algorithm is better.
-		 */
-		KASSERT(ni->ni_rates.rs_nrates > 0,
-			("new association w/ no rates!"));
-		ni->ni_txrate = ni->ni_rates.rs_nrates - 1;
-	}
 }
 
 int
@@ -3140,118 +3137,27 @@ ath_setcurmode(struct ath_softc *sc, enum ieee80211_phymode mode)
 	sc->sc_curmode = mode;
 }
 
-/*
- * Reset the rate control state for each 802.11 state transition.
- */
 void
-ath_rate_ctl_reset(struct ath_softc *sc, enum ieee80211_state state)
+ath_rssadapt_updatenode(void *arg, struct ieee80211_node *ni)
 {
-	struct ieee80211com *ic = &sc->sc_ic;
-	struct ieee80211_node *ni;
-	struct ath_node *an;
-
-	/*
-	 * When operating as a station the node table holds
-	 * the AP's that were discovered during scanning.
-	 * For any other operating mode we want to reset the
-	 * tx rate state of each node.
-	 */
-	if (ic->ic_opmode != IEEE80211_M_STA)
-		ieee80211_iterate_nodes(ic, ath_rate_ctl_tx_reset, NULL);
+	struct ath_node *an = ATH_NODE(ni);
 
-	/*
-	 * Reset local xmit state; this is really only meaningful
-	 * when operating in station or adhoc mode.
-	 */
-	ni = ic->ic_bss;
-	an = (struct ath_node *) ni;
-	an->an_tx_ok = an->an_tx_err = an->an_tx_retr = an->an_tx_upper = 0;
-	if (state == IEEE80211_S_RUN &&
-	    ic->ic_opmode != IEEE80211_M_MONITOR) {
-		/* start with highest negotiated rate */
-		KASSERT(ni->ni_rates.rs_nrates > 0,
-			("transition to RUN state w/ no rates!"));
-		ni->ni_txrate = ni->ni_rates.rs_nrates - 1;
-	} else {
-		/* use lowest rate */
-		ni->ni_txrate = 0;
-	}
+	ieee80211_rssadapt_updatestats(&an->an_rssadapt);
 }
 
 void
-ath_rate_ctl_tx_reset(void *arg, struct ieee80211_node *ni)
+ath_rssadapt_updatestats(void *arg)
 {
-	struct ath_node *an = (struct ath_node *) ni;
-	ni->ni_txrate = 0;		/* use lowest rate */
-	an->an_tx_ok = an->an_tx_err = an->an_tx_retr =
-	    an->an_tx_upper = 0;
-}
-
-/* 
- * Examine and potentially adjust the transmit rate.
- */
-void
-ath_rate_ctl(void *arg, struct ieee80211_node *ni)
-{
-	struct ath_softc *sc = arg;
-	struct ath_node *an = (struct ath_node *) ni;
-	struct ieee80211_rateset *rs = &ni->ni_rates;
-	int mod = 0, orate, enough;
-
-	/*
-	 * Rate control
-	 * XXX: very primitive version.
-	 */
-	sc->sc_stats.ast_rate_calls++;
-
-	enough = (an->an_tx_ok + an->an_tx_err >= 10);
-
-	/* no packet reached -> down */
-	if (an->an_tx_err > 0 && an->an_tx_ok == 0)
-		mod = -1;
-
-	/* all packets needs retry in average -> down */
-	if (enough && an->an_tx_ok < an->an_tx_retr)
-		mod = -1;
-
-	/* no error and less than 10% of packets needs retry -> up */
-	if (enough && an->an_tx_err == 0 && an->an_tx_ok > an->an_tx_retr * 10)
-		mod = 1;
+	struct ath_softc *sc = (struct ath_softc *)arg;
+	struct ieee80211com *ic = &sc->sc_ic;
 
-	orate = ni->ni_txrate;
-	switch (mod) {
-	case 0:
-		if (enough && an->an_tx_upper > 0)
-			an->an_tx_upper--;
-		break;
-	case -1:
-		if (ni->ni_txrate > 0) {
-			ni->ni_txrate--;
-			sc->sc_stats.ast_rate_drop++;
-		}
-		an->an_tx_upper = 0;
-		break;
-	case 1:
-		if (++an->an_tx_upper < 2)
-			break;
-		an->an_tx_upper = 0;
-		if (ni->ni_txrate + 1 < rs->rs_nrates) {
-			ni->ni_txrate++;
-			sc->sc_stats.ast_rate_raise++;
-		}
-		break;
+	if (ic->ic_opmode == IEEE80211_M_STA) {
+		ath_rssadapt_updatenode(arg, ic->ic_bss);
+	} else {
+		ieee80211_iterate_nodes(ic, ath_rssadapt_updatenode, arg);
 	}
 
-	if (ni->ni_txrate != orate) {
-		DPRINTF(ATH_DEBUG_RATE,
-		    ("%s: %dM -> %dM (%d ok, %d err, %d retr)\n",
-		    __func__,
-		    (rs->rs_rates[orate] & IEEE80211_RATE_VAL) / 2,
-		    (rs->rs_rates[ni->ni_txrate] & IEEE80211_RATE_VAL) / 2,
-		    an->an_tx_ok, an->an_tx_err, an->an_tx_retr));
-	}
-	if (ni->ni_txrate != orate || enough)
-		an->an_tx_ok = an->an_tx_err = an->an_tx_retr = 0;
+	timeout_add(&sc->sc_rssadapt_to, hz / 10);
 }
 
 #ifdef AR_DEBUG
diff --git a/sys/dev/ic/athvar.h b/sys/dev/ic/athvar.h
index 9e047bddca5..6596ddc29fa 100644
--- a/sys/dev/ic/athvar.h
+++ b/sys/dev/ic/athvar.h
@@ -1,4 +1,4 @@
-/*      $OpenBSD: athvar.h,v 1.14 2005/08/17 13:14:17 reyk Exp $  */
+/*      $OpenBSD: athvar.h,v 1.15 2005/09/22 10:17:04 reyk Exp $  */
 /*	$NetBSD: athvar.h,v 1.10 2004/08/10 01:03:53 dyoung Exp $	*/
 
 /*-
@@ -168,29 +168,27 @@ struct ath_tx_radiotap_header {
  * driver-specific node 
  */
 struct ath_node {
-	struct ieee80211_node an_node;	/* base class */
-	u_int		an_tx_ok;	/* tx ok pkt */
-	u_int		an_tx_err;	/* tx !ok pkt */
-	u_int		an_tx_retr;	/* tx retry count */
-	int		an_tx_upper;	/* tx upper rate req cnt */
-	u_int		an_tx_antenna;	/* antenna for last good frame */
-	u_int		an_rx_antenna;	/* antenna for last rcvd frame */
-	struct ath_recv_hist an_rx_hist[ATH_RHIST_SIZE];
-	u_int		an_rx_hist_next;/* index of next ``free entry'' */
+	struct ieee80211_node		an_node;	/* base class */
+	struct ieee80211_rssadapt	an_rssadapt;	/* rate adaption */
+	u_int				an_tx_antenna;	/* antenna for last good frame */
+	u_int				an_rx_antenna;	/* antenna for last rcvd frame */
+	struct ath_recv_hist		an_rx_hist[ATH_RHIST_SIZE];
+	u_int				an_rx_hist_next;/* index of next ``free entry'' */
 };
 #define	ATH_NODE(_n)	((struct ath_node *)(_n))
 
 struct ath_buf {
-	TAILQ_ENTRY(ath_buf)	bf_list;
-	bus_dmamap_t		bf_dmamap;	/* DMA map of the buffer */
-#define bf_nseg			bf_dmamap->dm_nsegs
-#define bf_mapsize		bf_dmamap->dm_mapsize
-#define bf_segs			bf_dmamap->dm_segs
-	struct ath_desc		*bf_desc;	/* virtual addr of desc */
-	bus_addr_t		bf_daddr;	/* physical addr of desc */
-	struct mbuf		*bf_m;		/* mbuf for buf */
-	struct ieee80211_node	*bf_node;	/* pointer to the node */
-#define	ATH_MAX_SCATTER		64
+	TAILQ_ENTRY(ath_buf)		bf_list;
+	bus_dmamap_t			bf_dmamap;	/* DMA map of the buffer */
+#define bf_nseg				bf_dmamap->dm_nsegs
+#define bf_mapsize			bf_dmamap->dm_mapsize
+#define bf_segs				bf_dmamap->dm_segs
+	struct ath_desc			*bf_desc;	/* virtual addr of desc */
+	bus_addr_t			bf_daddr;	/* physical addr of desc */
+	struct mbuf			*bf_m;		/* mbuf for buf */
+	struct ieee80211_node		*bf_node;	/* pointer to the node */
+	struct ieee80211_rssdesc	bf_id;
+#define	ATH_MAX_SCATTER			64
 };
 
 typedef struct ath_task {
@@ -299,6 +297,7 @@ struct ath_softc {
 	struct timeout		sc_cal_to;
 	struct timeval		sc_last_beacon;
 	struct timeout		sc_scan_to;
+	struct timeout		sc_rssadapt_to;
 #else
 	struct callout		sc_cal_ch;	/* callout handle for cals */
 	struct callout		sc_scan_ch;	/* callout handle for scan */