[net PATCH] octeon_ep: update BQL sent bytes before ringing doorbell

From: Shinas Rasheed
Date: Tue Oct 10 2023 - 07:50:45 EST


Sometimes Tx is completed immediately after doorbell is updated, which
causes Tx completion routing to update completion bytes before the
same packet bytes are updated in sent bytes in transmit function, hence
hitting BUG_ON() in dql_completed(). To avoid this, update BQL
sent bytes before ringing doorbell.

Fixes: 37d79d059606 ("octeon_ep: add Tx/Rx processing and interrupt support")
Signed-off-by: Shinas Rasheed <srasheed@xxxxxxxxxxx>
---
drivers/net/ethernet/marvell/octeon_ep/octep_main.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/marvell/octeon_ep/octep_main.c b/drivers/net/ethernet/marvell/octeon_ep/octep_main.c
index dbc518ff8276..314f9c661f93 100644
--- a/drivers/net/ethernet/marvell/octeon_ep/octep_main.c
+++ b/drivers/net/ethernet/marvell/octeon_ep/octep_main.c
@@ -718,6 +718,7 @@ static netdev_tx_t octep_start_xmit(struct sk_buff *skb,
/* Flush the hw descriptor before writing to doorbell */
wmb();

+ netdev_tx_sent_queue(iq->netdev_q, skb->len);
/* Ring Doorbell to notify the NIC there is a new packet */
writel(1, iq->doorbell_reg);
atomic_inc(&iq->instr_pending);
@@ -726,7 +727,6 @@ static netdev_tx_t octep_start_xmit(struct sk_buff *skb,
wi = 0;
iq->host_write_index = wi;

- netdev_tx_sent_queue(iq->netdev_q, skb->len);
iq->stats.instr_posted++;
skb_tx_timestamp(skb);
return NETDEV_TX_OK;
--
2.25.1