[PATCH v3 12/12] ath11k: avoid unnecessary lock contention in tx_completion path
From: P Praneesh <hidden>
Date: 2021-09-02 05:35:28
Also in:
ath11k
Subsystem:
atheros ath generic utilities, qualcomm atheros ath11k wireless driver, the rest · Maintainers:
Jeff Johnson, Linus Torvalds
Avoid unnecessary idr_find calls before the idr_remove calls. Because idr_remove gives the valid ptr if id is valid otherwise return NULL ptr. So removed the idr_find before idr_remove in tx completion path. Also no need to disable the bottom half preempt if it is already in the bottom half context, so modify the spin_lock_bh to spin_lock in the data tx completion path. Tested-on: IPQ8074 hw2.0 AHB WLAN.HK.2.4.0.1-01734-QCAHKSWPL_SILICONZ-1 v2 Co-developed-by: Karthikeyan Periyasamy <redacted> Signed-off-by: Karthikeyan Periyasamy <redacted> Signed-off-by: Jouni Malinen <redacted> Signed-off-by: P Praneesh <redacted> --- drivers/net/wireless/ath/ath11k/dp_tx.c | 32 ++++++++++++++------------------ 1 file changed, 14 insertions(+), 18 deletions(-)
diff --git a/drivers/net/wireless/ath/ath11k/dp_tx.c b/drivers/net/wireless/ath/ath11k/dp_tx.c
index 602184b..05bd86f 100644
--- a/drivers/net/wireless/ath/ath11k/dp_tx.c
+++ b/drivers/net/wireless/ath/ath11k/dp_tx.c@@ -288,20 +288,18 @@ static void ath11k_dp_tx_free_txbuf(struct ath11k_base *ab, u8 mac_id, struct sk_buff *msdu; struct ath11k_skb_cb *skb_cb; - spin_lock_bh(&tx_ring->tx_idr_lock); - msdu = idr_find(&tx_ring->txbuf_idr, msdu_id); - if (!msdu) { + spin_lock(&tx_ring->tx_idr_lock); + msdu = idr_remove(&tx_ring->txbuf_idr, msdu_id); + spin_unlock(&tx_ring->tx_idr_lock); + + if (unlikely(!msdu)) { ath11k_warn(ab, "tx completion for unknown msdu_id %d\n", msdu_id); - spin_unlock_bh(&tx_ring->tx_idr_lock); return; } skb_cb = ATH11K_SKB_CB(msdu); - idr_remove(&tx_ring->txbuf_idr, msdu_id); - spin_unlock_bh(&tx_ring->tx_idr_lock); - dma_unmap_single(ab->dev, skb_cb->paddr, msdu->len, DMA_TO_DEVICE); dev_kfree_skb_any(msdu);
@@ -320,12 +318,13 @@ ath11k_dp_tx_htt_tx_complete_buf(struct ath11k_base *ab, struct ath11k_skb_cb *skb_cb; struct ath11k *ar; - spin_lock_bh(&tx_ring->tx_idr_lock); - msdu = idr_find(&tx_ring->txbuf_idr, ts->msdu_id); + spin_lock(&tx_ring->tx_idr_lock); + msdu = idr_remove(&tx_ring->txbuf_idr, ts->msdu_id); + spin_unlock(&tx_ring->tx_idr_lock); + if (unlikely(!msdu)) { ath11k_warn(ab, "htt tx completion for unknown msdu_id %d\n", ts->msdu_id); - spin_unlock_bh(&tx_ring->tx_idr_lock); return; }
@@ -334,9 +333,6 @@ ath11k_dp_tx_htt_tx_complete_buf(struct ath11k_base *ab, ar = skb_cb->ar; - idr_remove(&tx_ring->txbuf_idr, ts->msdu_id); - spin_unlock_bh(&tx_ring->tx_idr_lock); - if (atomic_dec_and_test(&ar->dp.num_tx_pending)) wake_up(&ar->dp.tx_empty_waitq);
@@ -579,16 +575,16 @@ void ath11k_dp_tx_completion_handler(struct ath11k_base *ab, int ring_id) continue; } - spin_lock_bh(&tx_ring->tx_idr_lock); - msdu = idr_find(&tx_ring->txbuf_idr, msdu_id); + spin_lock(&tx_ring->tx_idr_lock); + msdu = idr_remove(&tx_ring->txbuf_idr, msdu_id); if (unlikely(!msdu)) { ath11k_warn(ab, "tx completion for unknown msdu_id %d\n", msdu_id); - spin_unlock_bh(&tx_ring->tx_idr_lock); + spin_unlock(&tx_ring->tx_idr_lock); continue; } - idr_remove(&tx_ring->txbuf_idr, msdu_id); - spin_unlock_bh(&tx_ring->tx_idr_lock); + + spin_unlock(&tx_ring->tx_idr_lock); ar = ab->pdevs[mac_id].ar;
--
2.7.4