From b0a6ba983e3663bf256ca2e79d17bb846878cd9e Mon Sep 17 00:00:00 2001 From: Sujith Manoharan Date: Wed, 13 Apr 2011 11:23:44 +0530 Subject: [PATCH] ath9k_htc: Fix beacon miss under heavy load Transmission of beacons becomes erratic when TX load is high, since the latency involved in the generation of a SWBA interrupt on the target to the actual sending of a beacon is quite high for USB devices. Fix this by adjusting the beacon response time. Signed-off-by: Sujith Manoharan Signed-off-by: John W. Linville --- drivers/net/wireless/ath/ath9k/htc.h | 7 ++++ .../net/wireless/ath/ath9k/htc_drv_beacon.c | 39 ++++++++++++++++--- 2 files changed, 41 insertions(+), 5 deletions(-) diff --git a/drivers/net/wireless/ath/ath9k/htc.h b/drivers/net/wireless/ath/ath9k/htc.h index a072a9eb3f3e..133fc6dc3929 100644 --- a/drivers/net/wireless/ath/ath9k/htc.h +++ b/drivers/net/wireless/ath/ath9k/htc.h @@ -358,6 +358,13 @@ struct ath_led { #define BSTUCK_THRESHOLD 10 +/* + * Adjust these when the max. no of beaconing interfaces is + * increased. + */ +#define DEFAULT_SWBA_RESPONSE 40 /* in TUs */ +#define MIN_SWBA_RESPONSE 10 /* in TUs */ + struct htc_beacon_config { struct ieee80211_vif *bslot[ATH9K_HTC_MAX_BCN_VIF]; u16 beacon_interval; diff --git a/drivers/net/wireless/ath/ath9k/htc_drv_beacon.c b/drivers/net/wireless/ath/ath9k/htc_drv_beacon.c index c96779c24296..48bc28823f6f 100644 --- a/drivers/net/wireless/ath/ath9k/htc_drv_beacon.c +++ b/drivers/net/wireless/ath/ath9k/htc_drv_beacon.c @@ -198,6 +198,15 @@ static void ath9k_htc_beacon_config_ap(struct ath9k_htc_priv *priv, intval /= ATH9K_HTC_MAX_BCN_VIF; nexttbtt = intval; + /* + * To reduce beacon misses under heavy TX load, + * set the beacon response time to a larger value. + */ + if (intval > DEFAULT_SWBA_RESPONSE) + priv->ah->config.sw_beacon_response_time = DEFAULT_SWBA_RESPONSE; + else + priv->ah->config.sw_beacon_response_time = MIN_SWBA_RESPONSE; + if (priv->op_flags & OP_TSF_RESET) { ath9k_hw_reset_tsf(priv->ah); priv->op_flags &= ~OP_TSF_RESET; @@ -216,9 +225,10 @@ static void ath9k_htc_beacon_config_ap(struct ath9k_htc_priv *priv, imask |= ATH9K_INT_SWBA; ath_dbg(common, ATH_DBG_CONFIG, - "AP Beacon config, intval: %d, nexttbtt: %u " + "AP Beacon config, intval: %d, nexttbtt: %u, resp_time: %d " "imask: 0x%x\n", - bss_conf->beacon_interval, nexttbtt, imask); + bss_conf->beacon_interval, nexttbtt, + priv->ah->config.sw_beacon_response_time, imask); ath9k_htc_beaconq_config(priv); @@ -252,12 +262,22 @@ static void ath9k_htc_beacon_config_adhoc(struct ath9k_htc_priv *priv, nexttbtt += intval; } while (nexttbtt < tsftu); + /* + * Only one IBSS interfce is allowed. + */ + if (intval > DEFAULT_SWBA_RESPONSE) + priv->ah->config.sw_beacon_response_time = DEFAULT_SWBA_RESPONSE; + else + priv->ah->config.sw_beacon_response_time = MIN_SWBA_RESPONSE; + if (priv->op_flags & OP_ENABLE_BEACON) imask |= ATH9K_INT_SWBA; ath_dbg(common, ATH_DBG_CONFIG, - "IBSS Beacon config, intval: %d, nexttbtt: %u, imask: 0x%x\n", - bss_conf->beacon_interval, nexttbtt, imask); + "IBSS Beacon config, intval: %d, nexttbtt: %u, " + "resp_time: %d, imask: 0x%x\n", + bss_conf->beacon_interval, nexttbtt, + priv->ah->config.sw_beacon_response_time, imask); WMI_CMD(WMI_DISABLE_INTR_CMDID); ath9k_hw_beaconinit(priv->ah, TU_TO_USEC(nexttbtt), TU_TO_USEC(intval)); @@ -317,6 +337,7 @@ static void ath9k_htc_send_buffered(struct ath9k_htc_priv *priv, static void ath9k_htc_send_beacon(struct ath9k_htc_priv *priv, int slot) { + struct ath_common *common = ath9k_hw_common(priv->ah); struct ieee80211_vif *vif; struct ath9k_htc_vif *avp; struct tx_beacon_header beacon_hdr; @@ -325,6 +346,7 @@ static void ath9k_htc_send_beacon(struct ath9k_htc_priv *priv, struct ieee80211_mgmt *mgmt; struct sk_buff *beacon; u8 *tx_fhdr; + int ret; memset(&beacon_hdr, 0, sizeof(struct tx_beacon_header)); memset(&tx_ctl, 0, sizeof(struct ath9k_htc_tx_ctl)); @@ -367,7 +389,14 @@ static void ath9k_htc_send_beacon(struct ath9k_htc_priv *priv, tx_fhdr = skb_push(beacon, sizeof(beacon_hdr)); memcpy(tx_fhdr, (u8 *) &beacon_hdr, sizeof(beacon_hdr)); - htc_send(priv->htc, beacon, priv->beacon_ep, &tx_ctl); + ret = htc_send(priv->htc, beacon, priv->beacon_ep, &tx_ctl); + if (ret != 0) { + if (ret == -ENOMEM) { + ath_dbg(common, ATH_DBG_BSTUCK, + "Failed to send beacon, no free TX buffer\n"); + } + dev_kfree_skb_any(beacon); + } spin_unlock_bh(&priv->beacon_lock); } -- 2.20.1