From: Lorenzo Bianconi <lorenzo@kernel.org>
Date: Tue, 21 Apr 2026 06:43:07 +0000 (+0200)
Subject: net: airoha: stop net_device TX queue before updating CPU index
X-Git-Tag: v7.1-rc2~22^2~40
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=3854de7b38be742cf7558476956d12414cb274f2;p=thirdparty%2Fkernel%2Flinux.git

net: airoha: stop net_device TX queue before updating CPU index

Currently, airoha_eth driver updates the CPU index register prior of
verifying whether the number of free descriptors has fallen below the
threshold.
Move net_device TX queue length check before updating the TX CPU index
in order to update TX CPU index even if there are more packets to be
transmitted but the net_device TX queue is going to be stopped
accounting the inflight packets.

Fixes: 1d304174106c ("net: airoha: Implement BQL support")
Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Link: https://patch.msgid.link/20260421-airoha-xmit-stop-condition-v1-1-e670d6a48467@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
---

diff --git a/drivers/net/ethernet/airoha/airoha_eth.c b/drivers/net/ethernet/airoha/airoha_eth.c
index daae15aa078c..27c85cd95750 100644
--- a/drivers/net/ethernet/airoha/airoha_eth.c
+++ b/drivers/net/ethernet/airoha/airoha_eth.c
@@ -2094,17 +2094,16 @@ static netdev_tx_t airoha_dev_xmit(struct sk_buff *skb,
 
 	skb_tx_timestamp(skb);
 	netdev_tx_sent_queue(txq, skb->len);
+	if (q->ndesc - q->queued < q->free_thr) {
+		netif_tx_stop_queue(txq);
+		q->txq_stopped = true;
+	}
 
 	if (netif_xmit_stopped(txq) || !netdev_xmit_more())
 		airoha_qdma_rmw(qdma, REG_TX_CPU_IDX(qid),
 				TX_RING_CPU_IDX_MASK,
 				FIELD_PREP(TX_RING_CPU_IDX_MASK, index));
 
-	if (q->ndesc - q->queued < q->free_thr) {
-		netif_tx_stop_queue(txq);
-		q->txq_stopped = true;
-	}
-
 	spin_unlock_bh(&q->lock);
 
 	return NETDEV_TX_OK;