From 4bd437ea40b81fb4c047034de6dca1b5af496fb0 Mon Sep 17 00:00:00 2001 From: Christian Lamparter Date: Mon, 27 Sep 2010 01:36:38 +0200 Subject: carl9170: revamp carl9170_tx_prepare David Miller complained about the driver's excessive use of variables in __packed structs. While I did not fully agree with his sole "performance" argument on all accounts. I do see some room for improvement in hot-paths on architectures without an efficient access to unaligned elements. This first patch (dare I say?) optimizes an important tx hot-path in the driver: carl9170_tx_prepare. Signed-off-by: Christian Lamparter Signed-off-by: John W. Linville --- drivers/net/wireless/ath/carl9170/tx.c | 155 ++++++++++++++++----------------- 1 file changed, 75 insertions(+), 80 deletions(-) (limited to 'drivers/net/wireless/ath/carl9170/tx.c') diff --git a/drivers/net/wireless/ath/carl9170/tx.c b/drivers/net/wireless/ath/carl9170/tx.c index e6be5e6c1723..b575c865142d 100644 --- a/drivers/net/wireless/ath/carl9170/tx.c +++ b/drivers/net/wireless/ath/carl9170/tx.c @@ -760,8 +760,8 @@ static int carl9170_tx_prepare(struct ar9170 *ar, struct sk_buff *skb) struct carl9170_tx_info *arinfo; unsigned int hw_queue; int i; - u16 keytype = 0; - u16 len, icv = 0; + __le16 mac_tmp; + u16 len; bool ampdu, no_ack; BUILD_BUG_ON(sizeof(*arinfo) > sizeof(info->rate_driver_data)); @@ -773,6 +773,10 @@ static int carl9170_tx_prepare(struct ar9170 *ar, struct sk_buff *skb) BUILD_BUG_ON(IEEE80211_TX_MAX_RATES < CARL9170_TX_MAX_RATES); + BUILD_BUG_ON(AR9170_MAX_VIRTUAL_MAC > + ((CARL9170_TX_SUPER_MISC_VIF_ID >> + CARL9170_TX_SUPER_MISC_VIF_ID_S) + 1)); + hw_queue = ar9170_qmap[carl9170_get_queue(ar, skb)]; hdr = (void *)skb->data; @@ -793,20 +797,37 @@ static int carl9170_tx_prepare(struct ar9170 *ar, struct sk_buff *skb) txc = (void *)skb_push(skb, sizeof(*txc)); memset(txc, 0, sizeof(*txc)); - ampdu = !!(info->flags & IEEE80211_TX_CTL_AMPDU); + SET_VAL(CARL9170_TX_SUPER_MISC_QUEUE, txc->s.misc, hw_queue); + + if (likely(cvif)) + SET_VAL(CARL9170_TX_SUPER_MISC_VIF_ID, txc->s.misc, cvif->id); + + if (unlikely(info->flags & IEEE80211_TX_CTL_SEND_AFTER_DTIM)) + txc->s.misc |= CARL9170_TX_SUPER_MISC_CAB; + + if (unlikely(ieee80211_is_probe_resp(hdr->frame_control))) + txc->s.misc |= CARL9170_TX_SUPER_MISC_FILL_IN_TSF; + + mac_tmp = cpu_to_le16(AR9170_TX_MAC_HW_DURATION | + AR9170_TX_MAC_BACKOFF); + mac_tmp |= cpu_to_le16((hw_queue << AR9170_TX_MAC_QOS_S) && + AR9170_TX_MAC_QOS); + no_ack = !!(info->flags & IEEE80211_TX_CTL_NO_ACK); + if (unlikely(no_ack)) + mac_tmp |= cpu_to_le16(AR9170_TX_MAC_NO_ACK); if (info->control.hw_key) { - icv = info->control.hw_key->icv_len; + len += info->control.hw_key->icv_len; switch (info->control.hw_key->cipher) { case WLAN_CIPHER_SUITE_WEP40: case WLAN_CIPHER_SUITE_WEP104: case WLAN_CIPHER_SUITE_TKIP: - keytype = AR9170_TX_MAC_ENCR_RC4; + mac_tmp |= cpu_to_le16(AR9170_TX_MAC_ENCR_RC4); break; case WLAN_CIPHER_SUITE_CCMP: - keytype = AR9170_TX_MAC_ENCR_AES; + mac_tmp |= cpu_to_le16(AR9170_TX_MAC_ENCR_AES); break; default: WARN_ON(1); @@ -814,48 +835,58 @@ static int carl9170_tx_prepare(struct ar9170 *ar, struct sk_buff *skb) } } - BUILD_BUG_ON(AR9170_MAX_VIRTUAL_MAC > - ((CARL9170_TX_SUPER_MISC_VIF_ID >> - CARL9170_TX_SUPER_MISC_VIF_ID_S) + 1)); - - txc->s.len = cpu_to_le16(len + sizeof(*txc)); - txc->f.length = cpu_to_le16(len + icv + 4); - SET_VAL(CARL9170_TX_SUPER_MISC_VIF_ID, txc->s.misc, - cvif ? cvif->id : 0); + ampdu = !!(info->flags & IEEE80211_TX_CTL_AMPDU); + if (ampdu) { + unsigned int density, factor; - txc->f.mac_control = cpu_to_le16(AR9170_TX_MAC_HW_DURATION | - AR9170_TX_MAC_BACKOFF); + if (unlikely(!sta || !cvif)) + goto err_out; - SET_VAL(CARL9170_TX_SUPER_MISC_QUEUE, txc->s.misc, hw_queue); + factor = min_t(unsigned int, 1u, + info->control.sta->ht_cap.ampdu_factor); - txc->f.mac_control |= cpu_to_le16(hw_queue << AR9170_TX_MAC_QOS_S); - txc->f.mac_control |= cpu_to_le16(keytype); - txc->f.phy_control = cpu_to_le32(0); + density = info->control.sta->ht_cap.ampdu_density; - if (no_ack) - txc->f.mac_control |= cpu_to_le16(AR9170_TX_MAC_NO_ACK); + if (density) { + /* + * Watch out! + * + * Otus uses slightly different density values than + * those from the 802.11n spec. + */ - if (info->flags & IEEE80211_TX_CTL_SEND_AFTER_DTIM) - txc->s.misc |= CARL9170_TX_SUPER_MISC_CAB; + density = max_t(unsigned int, density + 1, 7u); + } - txrate = &info->control.rates[0]; - if (carl9170_tx_rts_check(ar, txrate, ampdu, no_ack)) - txc->f.mac_control |= cpu_to_le16(AR9170_TX_MAC_PROT_RTS); - else if (carl9170_tx_cts_check(ar, txrate)) - txc->f.mac_control |= cpu_to_le16(AR9170_TX_MAC_PROT_CTS); + SET_VAL(CARL9170_TX_SUPER_AMPDU_DENSITY, + txc->s.ampdu_settings, density); - SET_VAL(CARL9170_TX_SUPER_RI_TRIES, txc->s.ri[0], txrate->count); - txc->f.phy_control |= carl9170_tx_physet(ar, info, txrate); + SET_VAL(CARL9170_TX_SUPER_AMPDU_FACTOR, + txc->s.ampdu_settings, factor); - if (info->flags & IEEE80211_TX_CTL_AMPDU) { - for (i = 1; i < CARL9170_TX_MAX_RATES; i++) { + for (i = 0; i < CARL9170_TX_MAX_RATES; i++) { txrate = &info->control.rates[i]; - if (txrate->idx >= 0) + if (txrate->idx >= 0) { + txc->s.ri[i] = + CARL9170_TX_SUPER_RI_AMPDU; + + if (WARN_ON(!(txrate->flags & + IEEE80211_TX_RC_MCS))) { + /* + * Not sure if it's even possible + * to aggregate non-ht rates with + * this HW. + */ + goto err_out; + } continue; + } txrate->idx = 0; txrate->count = ar->hw->max_rate_tries; } + + mac_tmp |= cpu_to_le16(AR9170_TX_MAC_AGGR); } /* @@ -878,57 +909,21 @@ static int carl9170_tx_prepare(struct ar9170 *ar, struct sk_buff *skb) txc->s.ri[i] |= (AR9170_TX_MAC_PROT_CTS << CARL9170_TX_SUPER_RI_ERP_PROT_S); - /* - * unaggregated fallback, in case aggregation - * proves to be unsuccessful and unreliable. - */ - if (ampdu && i < 3) - txc->s.ri[i] |= CARL9170_TX_SUPER_RI_AMPDU; - txc->s.rr[i - 1] = carl9170_tx_physet(ar, info, txrate); } - if (ieee80211_is_probe_resp(hdr->frame_control)) - txc->s.misc |= CARL9170_TX_SUPER_MISC_FILL_IN_TSF; - - if (ampdu) { - unsigned int density, factor; - - if (unlikely(!sta || !cvif)) - goto err_out; - - density = info->control.sta->ht_cap.ampdu_density; - factor = info->control.sta->ht_cap.ampdu_factor; - - if (density) { - /* - * Watch out! - * - * Otus uses slightly different density values than - * those from the 802.11n spec. - */ - - density = max_t(unsigned int, density + 1, 7u); - } - - factor = min_t(unsigned int, 1u, factor); - - SET_VAL(CARL9170_TX_SUPER_AMPDU_DENSITY, - txc->s.ampdu_settings, density); + txrate = &info->control.rates[0]; + SET_VAL(CARL9170_TX_SUPER_RI_TRIES, txc->s.ri[0], txrate->count); - SET_VAL(CARL9170_TX_SUPER_AMPDU_FACTOR, - txc->s.ampdu_settings, factor); + if (carl9170_tx_rts_check(ar, txrate, ampdu, no_ack)) + mac_tmp |= cpu_to_le16(AR9170_TX_MAC_PROT_RTS); + else if (carl9170_tx_cts_check(ar, txrate)) + mac_tmp |= cpu_to_le16(AR9170_TX_MAC_PROT_CTS); - if (info->control.rates[0].flags & IEEE80211_TX_RC_MCS) { - txc->f.mac_control |= cpu_to_le16(AR9170_TX_MAC_AGGR); - } else { - /* - * Not sure if it's even possible to aggregate - * non-ht rates with this HW. - */ - WARN_ON_ONCE(1); - } - } + txc->s.len = cpu_to_le16(skb->len); + txc->f.length = cpu_to_le16(len + FCS_LEN); + txc->f.mac_control = mac_tmp; + txc->f.phy_control = carl9170_tx_physet(ar, info, txrate); arinfo = (void *)info->rate_driver_data; arinfo->timeout = jiffies; -- cgit v1.2.3-59-g8ed1b