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 <chunkeey@googlemail.com> Signed-off-by: John W. Linville <linville@tuxdriver.com>
This commit is contained in:
Christian Lamparter
John W. Linville
parent
9c655c8be9
commit
4bd437ea40
@ -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));
|
||||
ampdu = !!(info->flags & IEEE80211_TX_CTL_AMPDU);
|
||||
if (ampdu) {
|
||||
unsigned int density, factor;
|
||||
|
||||
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);
|
||||
if (unlikely(!sta || !cvif))
|
||||
goto err_out;
|
||||
|
||||
txc->f.mac_control = cpu_to_le16(AR9170_TX_MAC_HW_DURATION |
|
||||
AR9170_TX_MAC_BACKOFF);
|
||||
factor = min_t(unsigned int, 1u,
|
||||
info->control.sta->ht_cap.ampdu_factor);
|
||||
|
||||
SET_VAL(CARL9170_TX_SUPER_MISC_QUEUE, txc->s.misc, hw_queue);
|
||||
density = info->control.sta->ht_cap.ampdu_density;
|
||||
|
||||
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);
|
||||
if (density) {
|
||||
/*
|
||||
* Watch out!
|
||||
*
|
||||
* Otus uses slightly different density values than
|
||||
* those from the 802.11n spec.
|
||||
*/
|
||||
|
||||
if (no_ack)
|
||||
txc->f.mac_control |= cpu_to_le16(AR9170_TX_MAC_NO_ACK);
|
||||
density = max_t(unsigned int, density + 1, 7u);
|
||||
}
|
||||
|
||||
if (info->flags & IEEE80211_TX_CTL_SEND_AFTER_DTIM)
|
||||
txc->s.misc |= CARL9170_TX_SUPER_MISC_CAB;
|
||||
SET_VAL(CARL9170_TX_SUPER_AMPDU_DENSITY,
|
||||
txc->s.ampdu_settings, density);
|
||||
|
||||
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_FACTOR,
|
||||
txc->s.ampdu_settings, factor);
|
||||
|
||||
SET_VAL(CARL9170_TX_SUPER_RI_TRIES, txc->s.ri[0], txrate->count);
|
||||
txc->f.phy_control |= carl9170_tx_physet(ar, info, txrate);
|
||||
|
||||
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;
|
||||
txrate = &info->control.rates[0];
|
||||
SET_VAL(CARL9170_TX_SUPER_RI_TRIES, txc->s.ri[0], txrate->count);
|
||||
|
||||
if (ampdu) {
|
||||
unsigned int density, 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 (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);
|
||||
|
||||
SET_VAL(CARL9170_TX_SUPER_AMPDU_FACTOR,
|
||||
txc->s.ampdu_settings, factor);
|
||||
|
||||
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;
|
||||
|
||||
Loading…
x
Reference in New Issue
Block a user