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mac80211: change rate control API to allow multi-rate retry

PATCH In review Felix Fietkau 2 participants 3 messages Sep 30, 2008

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#0 lore raw

PATCH v2 1/1 mac80211: change rate control API to allow multi-rate retry

This patch adjusts the rate control API to allow multi-rate retry if supported by the driver. The ieee80211_hw struct specifies how many alternate rate selections the driver supports. Moves iv_len and icv_len out of the CB into ieee80211_key_conf to make room for the extra rate retry data.

include/net/mac80211.h +27 -6
@@ -292,6 +292,20 @@
 #define IEEE80211_TX_INFO_DRIVER_DATA_PTRS \
 	(IEEE80211_TX_INFO_DRIVER_DATA_SIZE / sizeof(void *))
 
+/* maximum number of alternate rate retry stages */
+#define IEEE80211_TX_MAX_ALTRATE	3
+
+/**
+ * struct ieee80211_tx_altrate - alternate rate selection/status
+ *
+ * @rate_idx: rate index to attempt to send with
+ * @limit: number of retries before fallback
+ */
+struct ieee80211_tx_altrate {
+	s8 rate_idx;
+	u8 limit;
+};
+
 /**
  * struct ieee80211_tx_info - skb transmit information
  *
@@ -335,14 +349,14 @@
 			struct ieee80211_key_conf *hw_key;
 			struct ieee80211_sta *sta;
 			unsigned long jiffies;
-			s8 rts_cts_rate_idx, alt_retry_rate_idx;
+			s8 rts_cts_rate_idx;
 			u8 retry_limit;
-			u8 icv_len;
-			u8 iv_len;
+			struct ieee80211_tx_altrate retries[IEEE80211_TX_MAX_ALTRATE];
 		} control;
 		struct {
 			u64 ampdu_ack_map;
 			int ack_signal;
+			struct ieee80211_tx_altrate retries[IEEE80211_TX_MAX_ALTRATE + 1];
 			u8 retry_count;
 			bool excessive_retries;
 			u8 ampdu_ack_len;
@@ -635,6 +649,8 @@
  */
 struct ieee80211_key_conf {
 	enum ieee80211_key_alg alg;
+	u8 icv_len;
+	u8 iv_len;
 	u8 hw_key_idx;
 	u8 flags;
 	s8 keyidx;
@@ -828,6 +844,9 @@
  *	within &struct ieee80211_vif.
  * @sta_data_size: size (in bytes) of the drv_priv data area
  *	within &struct ieee80211_sta.
+ *
+ * @max_altrates: maximum number of alternate rate retry stages
+ * @max_altrate_tries: maximum number of tries for each stage
  */
 struct ieee80211_hw {
 	struct ieee80211_conf conf;
@@ -844,6 +863,8 @@
 	u16 ampdu_queues;
 	u16 max_listen_interval;
 	s8 max_signal;
+	u8 max_altrates;
+	u8 max_altrate_tries;
 };
 
 struct ieee80211_hw *wiphy_to_hw(struct wiphy *wiphy);
@@ -900,11 +921,11 @@
 
 static inline struct ieee80211_rate *
 ieee80211_get_alt_retry_rate(const struct ieee80211_hw *hw,
-			     const struct ieee80211_tx_info *c)
+			     const struct ieee80211_tx_info *c, int idx)
 {
-	if (c->control.alt_retry_rate_idx < 0)
+	if (c->control.retries[idx].rate_idx < 0)
 		return NULL;
-	return &hw->wiphy->bands[c->band]->bitrates[c->control.alt_retry_rate_idx];
+	return &hw->wiphy->bands[c->band]->bitrates[c->control.retries[idx].rate_idx];
 }
 
 /**
drivers/net/wireless/b43/xmit.c +3 -3
@@ -208,7 +208,7 @@
 	txrate = ieee80211_get_tx_rate(dev->wl->hw, info);
 	rate = txrate ? txrate->hw_value : B43_CCK_RATE_1MB;
 	rate_ofdm = b43_is_ofdm_rate(rate);
-	fbrate = ieee80211_get_alt_retry_rate(dev->wl->hw, info) ? : txrate;
+	fbrate = ieee80211_get_alt_retry_rate(dev->wl->hw, info, 0) ? : txrate;
 	rate_fb = fbrate->hw_value;
 	rate_fb_ofdm = b43_is_ofdm_rate(rate_fb);
 
@@ -252,7 +252,7 @@
 		}
 
 		/* Hardware appends ICV. */
-		plcp_fragment_len += info->control.icv_len;
+		plcp_fragment_len += info->control.hw_key->icv_len;
 
 		key_idx = b43_kidx_to_fw(dev, key_idx);
 		mac_ctl |= (key_idx << B43_TXH_MAC_KEYIDX_SHIFT) &
@@ -260,7 +260,7 @@
 		mac_ctl |= (key->algorithm << B43_TXH_MAC_KEYALG_SHIFT) &
 			   B43_TXH_MAC_KEYALG;
 		wlhdr_len = ieee80211_hdrlen(fctl);
-		iv_len = min((size_t) info->control.iv_len,
+		iv_len = min((size_t) info->control.hw_key->iv_len,
 			     ARRAY_SIZE(txhdr->iv));
 		memcpy(txhdr->iv, ((u8 *) wlhdr) + wlhdr_len, iv_len);
 	}
drivers/net/wireless/b43legacy/xmit.c +3 -3
@@ -210,7 +210,7 @@
 
 	rate = tx_rate->hw_value;
 	rate_ofdm = b43legacy_is_ofdm_rate(rate);
-	rate_fb = ieee80211_get_alt_retry_rate(dev->wl->hw, info) ? : tx_rate;
+	rate_fb = ieee80211_get_alt_retry_rate(dev->wl->hw, info, 0) ? : tx_rate;
 	rate_fb_ofdm = b43legacy_is_ofdm_rate(rate_fb->hw_value);
 
 	txhdr->mac_frame_ctl = wlhdr->frame_control;
@@ -243,7 +243,7 @@
 
 		if (key->enabled) {
 			/* Hardware appends ICV. */
-			plcp_fragment_len += info->control.icv_len;
+			plcp_fragment_len += info->control.hw_key->icv_len;
 
 			key_idx = b43legacy_kidx_to_fw(dev, key_idx);
 			mac_ctl |= (key_idx << B43legacy_TX4_MAC_KEYIDX_SHIFT) &
@@ -252,7 +252,7 @@
 				   B43legacy_TX4_MAC_KEYALG_SHIFT) &
 				   B43legacy_TX4_MAC_KEYALG;
 			wlhdr_len = ieee80211_hdrlen(wlhdr->frame_control);
-			iv_len = min((size_t)info->control.iv_len,
+			iv_len = min((size_t)info->control.hw_key->iv_len,
 				     ARRAY_SIZE(txhdr->iv));
 			memcpy(txhdr->iv, ((u8 *)wlhdr) + wlhdr_len, iv_len);
 		} else {
drivers/net/wireless/rtl8180_dev.c +2 -2
@@ -292,8 +292,8 @@
 	entry->plcp_len = cpu_to_le16(plcp_len);
 	entry->tx_buf = cpu_to_le32(mapping);
 	entry->frame_len = cpu_to_le32(skb->len);
-	entry->flags2 = info->control.alt_retry_rate_idx >= 0 ?
-		ieee80211_get_alt_retry_rate(dev, info)->bitrate << 4 : 0;
+	entry->flags2 = info->control.retries[0].rate_idx >= 0 ?
+		ieee80211_get_alt_retry_rate(dev, info, 0)->bitrate << 4 : 0;
 	entry->retry_limit = info->control.retry_limit;
 	entry->flags = cpu_to_le32(tx_flags);
 	__skb_queue_tail(&ring->queue, skb);
net/mac80211/tx.c +7 -6
@@ -454,15 +454,16 @@
 		if (unlikely(rsel.probe_idx >= 0)) {
 			info->flags |= IEEE80211_TX_CTL_RATE_CTRL_PROBE;
 			tx->flags |= IEEE80211_TX_PROBE_LAST_FRAG;
-			info->control.alt_retry_rate_idx = tx->rate_idx;
+			info->control.retries[0].rate_idx = tx->rate_idx;
+			info->control.retries[0].limit = tx->local->hw.max_altrate_tries;
 			tx->rate_idx = rsel.probe_idx;
-		} else
-			info->control.alt_retry_rate_idx = -1;
+		} else if (info->control.retries[0].limit == 0)
+			info->control.retries[0].rate_idx = -1;
 
 		if (unlikely(tx->rate_idx < 0))
 			return TX_DROP;
 	} else
-		info->control.alt_retry_rate_idx = -1;
+		info->control.retries[0].rate_idx = -1;
 
 	if (tx->sdata->bss_conf.use_cts_prot &&
 	    (tx->flags & IEEE80211_TX_FRAGMENTED) && (rsel.nonerp_idx >= 0)) {
@@ -521,7 +522,7 @@
 		 * frames.
 		 * TODO: The last fragment could still use multiple retry
 		 * rates. */
-		info->control.alt_retry_rate_idx = -1;
+		info->control.retries[0].rate_idx = -1;
 	}
 
 	/* Use CTS protection for unicast frames sent using extended rates if
@@ -551,7 +552,7 @@
 		int idx;
 
 		/* Do not use multiple retry rates when using RTS/CTS */
-		info->control.alt_retry_rate_idx = -1;
+		info->control.retries[0].rate_idx = -1;
 
 		/* Use min(data rate, max base rate) as CTS/RTS rate */
 		rate = &sband->bitrates[tx->rate_idx];
net/mac80211/wep.c +2 -2
@@ -313,8 +313,8 @@
 {
 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
 
-	info->control.iv_len = WEP_IV_LEN;
-	info->control.icv_len = WEP_ICV_LEN;
+	info->control.hw_key->iv_len = WEP_IV_LEN;
+	info->control.hw_key->icv_len = WEP_ICV_LEN;
 
 	if (!(tx->key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE)) {
 		if (ieee80211_wep_encrypt(tx->local, skb, tx->key))
net/mac80211/wpa.c +4 -4
@@ -152,8 +152,8 @@
 	int len, tail;
 	u8 *pos;
 
-	info->control.icv_len = TKIP_ICV_LEN;
-	info->control.iv_len = TKIP_IV_LEN;
+	info->control.hw_key->icv_len = TKIP_ICV_LEN;
+	info->control.hw_key->iv_len = TKIP_IV_LEN;
 
 	if ((tx->key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE) &&
 	    !(tx->key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_IV)) {
@@ -374,8 +374,8 @@
 	u8 *pos, *pn;
 	int i;
 
-	info->control.icv_len = CCMP_MIC_LEN;
-	info->control.iv_len = CCMP_HDR_LEN;
+	info->control.hw_key->icv_len = CCMP_MIC_LEN;
+	info->control.hw_key->iv_len = CCMP_HDR_LEN;
 
 	if ((tx->key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE) &&
 	    !(tx->key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_IV)) {
drivers/net/wireless/ath5k/base.c +1 -1
@@ -1164,7 +1164,7 @@
 
 	if (info->control.hw_key) {
 		keyidx = info->control.hw_key->hw_key_idx;
-		pktlen += info->control.icv_len;
+		pktlen += info->control.hw_key->icv_len;
 	}
 	ret = ah->ah_setup_tx_desc(ah, ds, pktlen,
 		ieee80211_get_hdrlen_from_skb(skb), AR5K_PKT_TYPE_NORMAL,
drivers/net/wireless/ath9k/xmit.c +1 -1
@@ -237,7 +237,7 @@
 
 	if (tx_info->control.hw_key) {
 		txctl->keyix = tx_info->control.hw_key->hw_key_idx;
-		txctl->frmlen += tx_info->control.icv_len;
+		txctl->frmlen += tx_info->control.hw_key->icv_len;
 
 		if (tx_info->control.hw_key->alg == ALG_WEP)
 			txctl->keytype = ATH9K_KEY_TYPE_WEP;
drivers/net/wireless/rt2x00/rt2x00crypto.c +2 -2
@@ -56,10 +56,10 @@
 	 * note that these lengths should only be added when
 	 * mac80211 does not generate it.
 	 */
-	overhead += tx_info->control.icv_len;
+	overhead += tx_info->control.hw_key->icv_len;
 
 	if (!(key->flags & IEEE80211_KEY_FLAG_GENERATE_IV))
-		overhead += tx_info->control.iv_len;
+		overhead += tx_info->control.hw_key->iv_len;
 
 	if (!(key->flags & IEEE80211_KEY_FLAG_GENERATE_MMIC)) {
 		if (key->alg == ALG_TKIP)
drivers/net/wireless/rt2x00/rt2x00queue.c +1 -1
@@ -374,7 +374,7 @@
 	struct queue_entry *entry = rt2x00queue_get_entry(queue, Q_INDEX);
 	struct txentry_desc txdesc;
 	struct skb_frame_desc *skbdesc;
-	unsigned int iv_len = IEEE80211_SKB_CB(skb)->control.iv_len;
+	unsigned int iv_len = IEEE80211_SKB_CB(skb)->control.hw_key->iv_len;
 
 	if (unlikely(rt2x00queue_full(queue)))
 		return -EINVAL;
#1 lore raw

PATCH 1/1 ath5k: implement multi-rate retry and fix tx status processing

Clean up the tx status reporting, fix retry counters (short retries are virtual collisions, not actual retries). Implement multi-rate retry support. This also fixes strong throughput fluctuations observed with rc80211_pid

drivers/net/wireless/ath5k/base.c +41 -3
@@ -583,6 +583,11 @@
 		}
 	}
 
+	/* set up multi-rate retry capabilities */
+	if (sc->ah->ah_version == AR5K_AR5212) {
+		hw->max_altrates = 3;
+		hw->max_altrate_tries = 15;
+	}
 
 	/* ready to process interrupts */
 	__clear_bit(ATH_STAT_INVALID, sc->status);
@@ -1149,7 +1154,9 @@
 	struct sk_buff *skb = bf->skb;
 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
 	unsigned int pktlen, flags, keyidx = AR5K_TXKEYIX_INVALID;
-	int ret;
+	struct ieee80211_rate *rate;
+	unsigned int mrr_rate[3], mrr_tries[3];
+	int i, ret;
 
 	flags = AR5K_TXDESC_INTREQ | AR5K_TXDESC_CLRDMASK;
 
@@ -1174,6 +1181,21 @@
 	if (ret)
 		goto err_unmap;
 
+	for (i = 0; i < 3; i++) {
+		rate = ieee80211_get_alt_retry_rate(sc->hw, info, i);
+		if (rate) {
+			mrr_rate[i] = rate->hw_value;
+			mrr_tries[i] = info->control.retries[i].limit;
+		} else {
+			mrr_rate[i] = 0;
+			mrr_tries[i] = 0;
+		}
+	}
+	ah->ah_setup_mrr_tx_desc(ah, ds,
+		mrr_rate[0], mrr_tries[0],
+		mrr_rate[1], mrr_tries[1],
+		mrr_rate[2], mrr_tries[2]);
+
 	ds->ds_link = 0;
 	ds->ds_data = bf->skbaddr;
 
@@ -1790,7 +1812,7 @@
 	struct ath5k_desc *ds;
 	struct sk_buff *skb;
 	struct ieee80211_tx_info *info;
-	int ret;
+	int i, ret;
 
 	spin_lock(&txq->lock);
 	list_for_each_entry_safe(bf, bf0, &txq->q, list) {
@@ -1812,7 +1834,23 @@
 		pci_unmap_single(sc->pdev, bf->skbaddr, skb->len,
 				PCI_DMA_TODEVICE);
 
-		info->status.retry_count = ts.ts_shortretry + ts.ts_longretry / 6;
+		info->tx_rate_idx = ath5k_hw_to_driver_rix(sc,
+				ts.ts_rate[ts.ts_final_idx]);
+		info->status.retry_count = ts.ts_longretry;
+
+		for (i = 0; i < 4; i++) {
+			struct ieee80211_tx_altrate *r =
+				&info->status.retries[i];
+
+			if (ts.ts_rate[i]) {
+				r->rate_idx = ath5k_hw_to_driver_rix(sc, ts.ts_rate[i]);
+				r->limit = ts.ts_retry[i];
+			} else {
+				r->rate_idx = -1;
+				r->limit = 0;
+			}
+		}
+
 		if (unlikely(ts.ts_status)) {
 			sc->ll_stats.dot11ACKFailureCount++;
 			if (ts.ts_status & AR5K_TXERR_XRETRY)
drivers/net/wireless/ath5k/desc.c +47 -22

97 lines not on this page · raw message

drivers/net/wireless/ath5k/ath5k.h +3 -1
@@ -418,7 +418,9 @@
 	u16	ts_seqnum;
 	u16	ts_tstamp;
 	u8	ts_status;
-	u8	ts_rate;
+	u8	ts_rate[4];
+	u8	ts_retry[4];
+	u8	ts_final_idx;
 	s8	ts_rssi;
 	u8	ts_shortretry;
 	u8	ts_longretry;
maintainer
#2 lore raw
In reply to Felix Fietkau

drivers/net/wireless/rt2x00/rt2x00queue.c line 377

Quoted 6 lines · Felix Fietkau
drivers/net/wireless/rt2x00/rt2x00queue.c +1 -1
@@ -374,7 +374,7 @@
 	struct queue_entry *entry = rt2x00queue_get_entry(queue, Q_INDEX);
 	struct txentry_desc txdesc;
 	struct skb_frame_desc *skbdesc;
-	unsigned int iv_len = IEEE80211_SKB_CB(skb)->control.iv_len;
+	unsigned int iv_len = IEEE80211_SKB_CB(skb)->control.hw_key->iv_len;

Won't that explode when hw_key is unset?

net/mac80211/wep.c line 320

Quoted 13 lines
net/mac80211/wep.c +2 -2
@@ -313,8 +313,8 @@
 {
        struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
 
-       info->control.iv_len = WEP_IV_LEN;
-       info->control.icv_len = WEP_ICV_LEN;
+       info->control.hw_key->iv_len = WEP_IV_LEN;
+       info->control.hw_key->icv_len = WEP_ICV_LEN;
 
        if (!(tx->key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE)) {
                if (ieee80211_wep_encrypt(tx->local, skb, tx->key))

I don't think you should set this here, just set it when the key algorithm is fixed initially, that way it's also already valid when the key is put into hw accel.

johannes