From: Qi Zhou Date: Wed, 22 Jul 2015 20:38:24 +0000 (-0400) Subject: ath10k: Improve performance by reducing tx_lock contention X-Git-Url: http://drtracing.org/?a=commitdiff_plain;h=005fb161310f72070ad5f4352d6b81ffaca8a11e;p=deliverable%2Flinux.git ath10k: Improve performance by reducing tx_lock contention During tx completion, tx_lock is held for longer than required, preventing efficient refill of htt->pending_tx. Refactor the code so that only MSDU related operations are protected by the lock. Improves downstream performance on a dual-core ARM Freescale LS1024A (f.k.a. Mindspeed Comcerto 2000) AP with a 3x3 client from 495 to 580 Mbps. Other CPU bound multicore systems may also benefit. Signed-off-by: Denton Gentry Signed-off-by: Avery Pennarun [mfaltesek@google.com: removed conflicting code for tracking msdu_ids.] Signed-off-by: Marty Faltesek Signed-off-by: Kalle Valo --- diff --git a/drivers/net/wireless/ath/ath10k/htt_rx.c b/drivers/net/wireless/ath/ath10k/htt_rx.c index 61a26264728a..5e54c393767e 100644 --- a/drivers/net/wireless/ath/ath10k/htt_rx.c +++ b/drivers/net/wireless/ath/ath10k/htt_rx.c @@ -1631,8 +1631,6 @@ static void ath10k_htt_rx_frm_tx_compl(struct ath10k *ar, __le16 msdu_id; int i; - lockdep_assert_held(&htt->tx_lock); - switch (status) { case HTT_DATA_TX_STATUS_NO_ACK: tx_done.no_ack = true; @@ -1998,15 +1996,11 @@ void ath10k_htt_t2h_msg_handler(struct ath10k *ar, struct sk_buff *skb) break; } - spin_lock_bh(&htt->tx_lock); ath10k_txrx_tx_unref(htt, &tx_done); - spin_unlock_bh(&htt->tx_lock); break; } case HTT_T2H_MSG_TYPE_TX_COMPL_IND: - spin_lock_bh(&htt->tx_lock); - __skb_queue_tail(&htt->tx_compl_q, skb); - spin_unlock_bh(&htt->tx_lock); + skb_queue_tail(&htt->tx_compl_q, skb); tasklet_schedule(&htt->txrx_compl_task); return; case HTT_T2H_MSG_TYPE_SEC_IND: { @@ -2095,12 +2089,10 @@ static void ath10k_htt_txrx_compl_task(unsigned long ptr) struct htt_resp *resp; struct sk_buff *skb; - spin_lock_bh(&htt->tx_lock); - while ((skb = __skb_dequeue(&htt->tx_compl_q))) { + while ((skb = skb_dequeue(&htt->tx_compl_q))) { ath10k_htt_rx_frm_tx_compl(htt->ar, skb); dev_kfree_skb_any(skb); } - spin_unlock_bh(&htt->tx_lock); spin_lock_bh(&htt->rx_ring.lock); while ((skb = __skb_dequeue(&htt->rx_compl_q))) { diff --git a/drivers/net/wireless/ath/ath10k/htt_tx.c b/drivers/net/wireless/ath/ath10k/htt_tx.c index a97dd9d4295b..2c0627b7141b 100644 --- a/drivers/net/wireless/ath/ath10k/htt_tx.c +++ b/drivers/net/wireless/ath/ath10k/htt_tx.c @@ -134,9 +134,7 @@ static int ath10k_htt_tx_clean_up_pending(int msdu_id, void *skb, void *ctx) tx_done.discard = 1; tx_done.msdu_id = msdu_id; - spin_lock_bh(&htt->tx_lock); ath10k_txrx_tx_unref(htt, &tx_done); - spin_unlock_bh(&htt->tx_lock); return 0; } @@ -429,12 +427,11 @@ int ath10k_htt_mgmt_tx(struct ath10k_htt *htt, struct sk_buff *msdu) spin_lock_bh(&htt->tx_lock); res = ath10k_htt_tx_alloc_msdu_id(htt, msdu); + spin_unlock_bh(&htt->tx_lock); if (res < 0) { - spin_unlock_bh(&htt->tx_lock); goto err_tx_dec; } msdu_id = res; - spin_unlock_bh(&htt->tx_lock); txdesc = ath10k_htc_alloc_skb(ar, len); if (!txdesc) { @@ -506,12 +503,11 @@ int ath10k_htt_tx(struct ath10k_htt *htt, struct sk_buff *msdu) spin_lock_bh(&htt->tx_lock); res = ath10k_htt_tx_alloc_msdu_id(htt, msdu); + spin_unlock_bh(&htt->tx_lock); if (res < 0) { - spin_unlock_bh(&htt->tx_lock); goto err_tx_dec; } msdu_id = res; - spin_unlock_bh(&htt->tx_lock); prefetch_len = min(htt->prefetch_len, msdu->len); prefetch_len = roundup(prefetch_len, 4); diff --git a/drivers/net/wireless/ath/ath10k/txrx.c b/drivers/net/wireless/ath/ath10k/txrx.c index 6cf289158840..e4a9c4c8d0cb 100644 --- a/drivers/net/wireless/ath/ath10k/txrx.c +++ b/drivers/net/wireless/ath/ath10k/txrx.c @@ -53,8 +53,6 @@ void ath10k_txrx_tx_unref(struct ath10k_htt *htt, struct ath10k_skb_cb *skb_cb; struct sk_buff *msdu; - lockdep_assert_held(&htt->tx_lock); - ath10k_dbg(ar, ATH10K_DBG_HTT, "htt tx completion msdu_id %u discard %d no_ack %d success %d\n", tx_done->msdu_id, !!tx_done->discard, @@ -66,12 +64,19 @@ void ath10k_txrx_tx_unref(struct ath10k_htt *htt, return; } + spin_lock_bh(&htt->tx_lock); msdu = idr_find(&htt->pending_tx, tx_done->msdu_id); if (!msdu) { ath10k_warn(ar, "received tx completion for invalid msdu_id: %d\n", tx_done->msdu_id); + spin_unlock_bh(&htt->tx_lock); return; } + ath10k_htt_tx_free_msdu_id(htt, tx_done->msdu_id); + __ath10k_htt_tx_dec_pending(htt); + if (htt->num_pending_tx == 0) + wake_up(&htt->empty_tx_wq); + spin_unlock_bh(&htt->tx_lock); skb_cb = ATH10K_SKB_CB(msdu); @@ -90,7 +95,7 @@ void ath10k_txrx_tx_unref(struct ath10k_htt *htt, if (tx_done->discard) { ieee80211_free_txskb(htt->ar->hw, msdu); - goto exit; + return; } if (!(info->flags & IEEE80211_TX_CTL_NO_ACK)) @@ -104,12 +109,6 @@ void ath10k_txrx_tx_unref(struct ath10k_htt *htt, ieee80211_tx_status(htt->ar->hw, msdu); /* we do not own the msdu anymore */ - -exit: - ath10k_htt_tx_free_msdu_id(htt, tx_done->msdu_id); - __ath10k_htt_tx_dec_pending(htt); - if (htt->num_pending_tx == 0) - wake_up(&htt->empty_tx_wq); } struct ath10k_peer *ath10k_peer_find(struct ath10k *ar, int vdev_id,