From c1056a59aee1d352c7113c2cba4d214bf5f195af Mon Sep 17 00:00:00 2001 From: Michael Chan Date: Mon, 13 Nov 2023 16:16:21 -0800 Subject: [PATCH] bnxt_en: Optimize xmit_more TX path Now that we use the cumulative consumer index scheme for TX completion, we don't need to have one TX completion per TX packet in the xmit_more code path. Set the TX_BD_FLAGS_NO_CMPL flag if xmit_more is true. Fallback to one interrupt per packet if the ring is filled beyond bp->tx_wake_thresh. Also, move the wmb() to bnxt_txr_db_kick(). When xmit_more is true, we'll skip the bnxt_txr_db_kick() call and there is no need to call wmb() to sync. the TX BD data. Reviewed-by: Somnath Kotur Reviewed-by: Pavan Chebbi Signed-off-by: Michael Chan Signed-off-by: David S. Miller --- drivers/net/ethernet/broadcom/bnxt/bnxt.c | 16 ++++++++++------ 1 file changed, 10 insertions(+), 6 deletions(-) diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt.c b/drivers/net/ethernet/broadcom/bnxt/bnxt.c index d1af1d2ff800..e6ac1bd21bb3 100644 --- a/drivers/net/ethernet/broadcom/bnxt/bnxt.c +++ b/drivers/net/ethernet/broadcom/bnxt/bnxt.c @@ -381,6 +381,8 @@ static u16 bnxt_xmit_get_cfa_action(struct sk_buff *skb) static void bnxt_txr_db_kick(struct bnxt *bp, struct bnxt_tx_ring_info *txr, u16 prod) { + /* Sync BD data before updating doorbell */ + wmb(); bnxt_db_write(bp, &txr->tx_db, prod); txr->kick_pending = 0; } @@ -388,7 +390,7 @@ static void bnxt_txr_db_kick(struct bnxt *bp, struct bnxt_tx_ring_info *txr, static netdev_tx_t bnxt_start_xmit(struct sk_buff *skb, struct net_device *dev) { struct bnxt *bp = netdev_priv(dev); - struct tx_bd *txbd; + struct tx_bd *txbd, *txbd0; struct tx_bd_ext *txbd1; struct netdev_queue *txq; int i; @@ -602,6 +604,7 @@ static netdev_tx_t bnxt_start_xmit(struct sk_buff *skb, struct net_device *dev) txbd1->tx_bd_cfa_meta = cpu_to_le32(vlan_tag_flags); txbd1->tx_bd_cfa_action = cpu_to_le32(cfa_action << TX_BD_CFA_ACTION_SHIFT); + txbd0 = txbd; for (i = 0; i < last_frag; i++) { skb_frag_t *frag = &skb_shinfo(skb)->frags[i]; @@ -633,16 +636,17 @@ static netdev_tx_t bnxt_start_xmit(struct sk_buff *skb, struct net_device *dev) skb_tx_timestamp(skb); - /* Sync BD data before updating doorbell */ - wmb(); - prod = NEXT_TX(prod); WRITE_ONCE(txr->tx_prod, prod); - if (!netdev_xmit_more() || netif_xmit_stopped(txq)) + if (!netdev_xmit_more() || netif_xmit_stopped(txq)) { bnxt_txr_db_kick(bp, txr, prod); - else + } else { + if (free_size >= bp->tx_wake_thresh) + txbd0->tx_bd_len_flags_type |= + cpu_to_le32(TX_BD_FLAGS_NO_CMPL); txr->kick_pending = 1; + } tx_done: