Commit 061b9bedbef1 ("ionic: Rework Tx start/stop flow") replaced ionic_maybe_stop_tx() with netif_txq_maybe_stop() to get the memory barriers around the stop/start bits right, but did not cover the stop in ionic_tx() added by commit 138506ab249b ("ionic: Check stop no restart"). Convert the remaining site. netif_txq_maybe_stop() requires the ring indexes to be updated before it is invoked, so the post has to come first. But ring_dbell comes from __netdev_tx_sent_queue(), which runs after that and reads the stop bit, so it is not known in time to pass to ionic_txq_post(). Post without the doorbell and ring it separately. The stop condition is unchanged. The re-check only clears the stop bit when space has become available, so the doorbell starvation fixed by commit 138506ab249b ("ionic: Check stop no restart") cannot recur. Fixes: 138506ab249b ("ionic: Check stop no restart") Assisted-by: Claude:claude-opus-4-8 Signed-off-by: Nikhil P. Rao Reviewed-by: Brett Creeley --- drivers/net/ethernet/pensando/ionic/ionic_txrx.c | 13 ++++++++++--- 1 file changed, 10 insertions(+), 3 deletions(-) diff --git a/drivers/net/ethernet/pensando/ionic/ionic_txrx.c b/drivers/net/ethernet/pensando/ionic/ionic_txrx.c index e436e3231e86..2543a8ff8547 100644 --- a/drivers/net/ethernet/pensando/ionic/ionic_txrx.c +++ b/drivers/net/ethernet/pensando/ionic/ionic_txrx.c @@ -1672,15 +1672,22 @@ static int ionic_tx(struct net_device *netdev, struct ionic_queue *q, stats->pkts++; stats->bytes += skb->len; + ionic_txq_post(q, false); + if (likely(!ionic_txq_hwstamp_enabled(q))) { struct netdev_queue *ndq = q_to_ndq(netdev, q); - if (unlikely(!ionic_q_has_space(q, MAX_SKB_FRAGS + 1))) - netif_tx_stop_queue(ndq); + netif_txq_maybe_stop(ndq, ionic_q_space_avail(q), + MAX_SKB_FRAGS + 1, MAX_SKB_FRAGS + 1); ring_dbell = __netdev_tx_sent_queue(ndq, skb->len, netdev_xmit_more()); } - ionic_txq_post(q, ring_dbell); + + if (ring_dbell) { + ionic_dbell_ring(q->lif->kern_dbpage, q->hw_type, + q->dbval | q->head_idx); + q->dbell_jiffies = jiffies; + } return 0; } -- 2.43.0