From: Vasanthakumar Thiagarajan Date: Wed, 15 Jul 2009 00:14:10 +0000 (-0400) Subject: ath9k: Remove dead code in rate control X-Git-Tag: upstream/snapshot3+hdmi~17671^2~544^2~70 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=39a4cafe1638bb21f335b210d037cd2cd8ce6c08;p=platform%2Fadaptation%2Frenesas_rcar%2Frenesas_kernel.git ath9k: Remove dead code in rate control ath9k rate control is based on only PER (packet error rate), remove unused code which was intented to do rssi based rate selection. Signed-off-by: Vasanthakumar Thiagarajan Signed-off-by: John W. Linville --- diff --git a/drivers/net/wireless/ath/ath9k/rc.c b/drivers/net/wireless/ath/ath9k/rc.c index e66734c..a39b1a7 100644 --- a/drivers/net/wireless/ath/ath9k/rc.c +++ b/drivers/net/wireless/ath/ath9k/rc.c @@ -607,47 +607,14 @@ static u8 ath_rc_get_highest_rix(struct ath_softc *sc, const struct ath_rate_table *rate_table, int *is_probing) { - u32 dt, best_thruput, this_thruput, now_msec; + u32 best_thruput, this_thruput, now_msec; u8 rate, next_rate, best_rate, maxindex, minindex; - int8_t rssi_last, rssi_reduce = 0, index = 0; - - *is_probing = 0; - - rssi_last = median(ath_rc_priv->rssi_last, - ath_rc_priv->rssi_last_prev, - ath_rc_priv->rssi_last_prev2); - - /* - * Age (reduce) last ack rssi based on how old it is. - * The bizarre numbers are so the delta is 160msec, - * meaning we divide by 16. - * 0msec <= dt <= 25msec: don't derate - * 25msec <= dt <= 185msec: derate linearly from 0 to 10dB - * 185msec <= dt: derate by 10dB - */ + int8_t index = 0; now_msec = jiffies_to_msecs(jiffies); - dt = now_msec - ath_rc_priv->rssi_time; - - if (dt >= 185) - rssi_reduce = 10; - else if (dt >= 25) - rssi_reduce = (u8)((dt - 25) >> 4); - - /* Now reduce rssi_last by rssi_reduce */ - if (rssi_last < rssi_reduce) - rssi_last = 0; - else - rssi_last -= rssi_reduce; - - /* - * Now look up the rate in the rssi table and return it. - * If no rates match then we return 0 (lowest rate) - */ - + *is_probing = 0; best_thruput = 0; maxindex = ath_rc_priv->max_valid_rate-1; - minindex = 0; best_rate = minindex; @@ -687,7 +654,6 @@ static u8 ath_rc_get_highest_rix(struct ath_softc *sc, } rate = best_rate; - ath_rc_priv->rssi_last_lookup = rssi_last; /* * Must check the actual rate (ratekbps) to account for @@ -977,10 +943,6 @@ static bool ath_rc_update_per(struct ath_softc *sc, (nretry_to_per_lookup[retries] >> 3)); } - ath_rc_priv->rssi_last_prev2 = ath_rc_priv->rssi_last_prev; - ath_rc_priv->rssi_last_prev = ath_rc_priv->rssi_last; - ath_rc_priv->rssi_last = tx_info_priv->tx.ts_rssi; - ath_rc_priv->rssi_time = now_msec; /* * If we got at most one retry then increase the max rate if @@ -1024,18 +986,9 @@ static bool ath_rc_update_per(struct ath_softc *sc, /* * Don't update anything. We don't know if * this was because of collisions or poor signal. - * - * Later: if rssi_ack is close to - * ath_rc_priv->state[txRate].rssi_thres and we see lots - * of retries, then we could increase - * ath_rc_priv->state[txRate].rssi_thres. */ ath_rc_priv->hw_maxretry_pktcnt = 0; } else { - int32_t rssi_ackAvg; - int8_t rssi_thres; - int8_t rssi_ack_vmin; - /* * It worked with no retries. First ignore bogus (small) * rssi_ack values. @@ -1045,43 +998,9 @@ static bool ath_rc_update_per(struct ath_softc *sc, ath_rc_priv->hw_maxretry_pktcnt++; } - if (tx_info_priv->tx.ts_rssi < - rate_table->info[tx_rate].rssi_ack_validmin) - goto exit; - - /* Average the rssi */ - if (tx_rate != ath_rc_priv->rssi_sum_rate) { - ath_rc_priv->rssi_sum_rate = tx_rate; - ath_rc_priv->rssi_sum = - ath_rc_priv->rssi_sum_cnt = 0; - } - - ath_rc_priv->rssi_sum += tx_info_priv->tx.ts_rssi; - ath_rc_priv->rssi_sum_cnt++; - - if (ath_rc_priv->rssi_sum_cnt < 4) - goto exit; - - rssi_ackAvg = - (ath_rc_priv->rssi_sum + 2) / 4; - rssi_thres = - ath_rc_priv->state[tx_rate].rssi_thres; - rssi_ack_vmin = - rate_table->info[tx_rate].rssi_ack_validmin; - - ath_rc_priv->rssi_sum = - ath_rc_priv->rssi_sum_cnt = 0; - - /* Now reduce the current rssi threshold */ - if ((rssi_ackAvg < rssi_thres + 2) && - (rssi_thres > rssi_ack_vmin)) { - ath_rc_priv->state[tx_rate].rssi_thres--; - } - - state_change = true; } } -exit: + return state_change; } @@ -1093,11 +1012,6 @@ static void ath_rc_update_ht(struct ath_softc *sc, struct ath_tx_info_priv *tx_info_priv, int tx_rate, int xretries, int retries) { -#define CHK_RSSI(rate) \ - ((ath_rc_priv->state[(rate)].rssi_thres + \ - rate_table->info[(rate)].rssi_ack_deltamin) > \ - ath_rc_priv->state[(rate)+1].rssi_thres) - u32 now_msec = jiffies_to_msecs(jiffies); int rate; u8 last_per; @@ -1108,13 +1022,6 @@ static void ath_rc_update_ht(struct ath_softc *sc, if ((tx_rate < 0) || (tx_rate > rate_table->rate_cnt)) return; - /* To compensate for some imbalance between ctrl and ext. channel */ - - if (WLAN_RC_PHY_40(rate_table->info[tx_rate].phy)) - tx_info_priv->tx.ts_rssi = - tx_info_priv->tx.ts_rssi < 3 ? 0 : - tx_info_priv->tx.ts_rssi - 3; - last_per = ath_rc_priv->state[tx_rate].per; /* Update PER first */ @@ -1136,51 +1043,6 @@ static void ath_rc_update_ht(struct ath_softc *sc, ath_rc_priv->probe_time = now_msec; } - if (state_change) { - /* - * Make sure the rates above this have higher rssi thresholds. - * (Note: Monotonicity is kept within the OFDM rates and - * within the CCK rates. However, no adjustment is - * made to keep the rssi thresholds monotonically - * increasing between the CCK and OFDM rates.) - */ - for (rate = tx_rate; rate < size - 1; rate++) { - if (rate_table->info[rate+1].phy != - rate_table->info[tx_rate].phy) - break; - - if (CHK_RSSI(rate)) { - ath_rc_priv->state[rate+1].rssi_thres = - ath_rc_priv->state[rate].rssi_thres + - rate_table->info[rate].rssi_ack_deltamin; - } - } - - /* Make sure the rates below this have lower rssi thresholds. */ - for (rate = tx_rate - 1; rate >= 0; rate--) { - if (rate_table->info[rate].phy != - rate_table->info[tx_rate].phy) - break; - - if (CHK_RSSI(rate)) { - if (ath_rc_priv->state[rate+1].rssi_thres < - rate_table->info[rate].rssi_ack_deltamin) - ath_rc_priv->state[rate].rssi_thres = 0; - else { - ath_rc_priv->state[rate].rssi_thres = - ath_rc_priv->state[rate+1].rssi_thres - - rate_table->info[rate].rssi_ack_deltamin; - } - - if (ath_rc_priv->state[rate].rssi_thres < - rate_table->info[rate].rssi_ack_validmin) { - ath_rc_priv->state[rate].rssi_thres = - rate_table->info[rate].rssi_ack_validmin; - } - } - } - } - /* Make sure the rates below this have lower PER */ /* Monotonicity is kept only for rates below the current rate. */ if (ath_rc_priv->state[tx_rate].per < last_per) { @@ -1205,19 +1067,6 @@ static void ath_rc_update_ht(struct ath_softc *sc, ath_rc_priv->state[rate].per; } - /* Every so often, we reduce the thresholds and - * PER (different for CCK and OFDM). */ - if (now_msec - ath_rc_priv->rssi_down_time >= - rate_table->rssi_reduce_interval) { - - for (rate = 0; rate < size; rate++) { - if (ath_rc_priv->state[rate].rssi_thres > - rate_table->info[rate].rssi_ack_validmin) - ath_rc_priv->state[rate].rssi_thres -= 1; - } - ath_rc_priv->rssi_down_time = now_msec; - } - /* Every so often, we reduce the thresholds * and PER (different for CCK and OFDM). */ if (now_msec - ath_rc_priv->per_down_time >= @@ -1233,7 +1082,6 @@ static void ath_rc_update_ht(struct ath_softc *sc, ath_debug_stat_retries(sc, tx_rate, xretries, retries, ath_rc_priv->state[tx_rate].per); -#undef CHK_RSSI } static int ath_rc_get_rateindex(const struct ath_rate_table *rate_table, @@ -1369,8 +1217,6 @@ static void ath_rc_init(struct ath_softc *sc, /* Initialize thresholds according to the global rate table */ for (i = 0 ; i < ath_rc_priv->rate_table_size; i++) { - ath_rc_priv->state[i].rssi_thres = - rate_table->info[i].rssi_ack_validmin; ath_rc_priv->state[i].per = 0; } @@ -1631,7 +1477,6 @@ static void *ath_rate_alloc_sta(void *priv, struct ieee80211_sta *sta, gfp_t gfp return NULL; } - rate_priv->rssi_down_time = jiffies_to_msecs(jiffies); rate_priv->tx_triglevel_max = sc->sc_ah->caps.tx_triglevel_max; return rate_priv;