[PATCH net v3 9/9] net: stmmac: Always arm TX Timer at end of transmission start

[Jose Abreu]

If TX Coalesce timer is enabled we should always arm it, otherwise we
may hit the case where an interrupt is missed and the TX Queue will
timeout.

Arming the timer does not necessarly mean it will run the tx_clean()
because this function is wrapped around NAPI launcher.

Fixes: 9125cdd1be11 ("stmmac: add the initial tx coalesce schema")
Signed-off-by: Jose Abreu <Jose.Abreu@xxxxxxxxxxxx>

---
Cc: Giuseppe Cavallaro <peppe.cavallaro@xxxxxx>
Cc: Alexandre Torgue <alexandre.torgue@xxxxxx>
Cc: Jose Abreu <joabreu@xxxxxxxxxxxx>
Cc: "David S. Miller" <davem@xxxxxxxxxxxxx>
Cc: Maxime Coquelin <mcoquelin.stm32@xxxxxxxxx>
Cc: netdev@xxxxxxxxxxxxxxx
Cc: linux-stm32@xxxxxxxxxxxxxxxxxxxxxxxxxxxx
Cc: linux-arm-kernel@xxxxxxxxxxxxxxxxxxx
Cc: linux-kernel@xxxxxxxxxxxxxxx
---
 drivers/net/ethernet/stmicro/stmmac/stmmac_main.c | 6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
index 1cb466dd5b3f..6f51a265459d 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
@@ -3053,8 +3053,6 @@ static netdev_tx_t stmmac_tso_xmit(struct sk_buff *skb, struct net_device *dev)
 		tx_q->tx_count_frames = 0;
 		stmmac_set_tx_ic(priv, desc);
 		priv->xstats.tx_set_ic_bit++;
-	} else {
-		stmmac_tx_timer_arm(priv, queue);
 	}
 
 	/* We've used all descriptors we need for this skb, however,
@@ -3125,6 +3123,7 @@ static netdev_tx_t stmmac_tso_xmit(struct sk_buff *skb, struct net_device *dev)
 
 	tx_q->tx_tail_addr = tx_q->dma_tx_phy + (tx_q->cur_tx * sizeof(*desc));
 	stmmac_set_tx_tail_ptr(priv, priv->ioaddr, tx_q->tx_tail_addr, queue);
+	stmmac_tx_timer_arm(priv, queue);
 
 	return NETDEV_TX_OK;
 
@@ -3276,8 +3275,6 @@ static netdev_tx_t stmmac_xmit(struct sk_buff *skb, struct net_device *dev)
 		tx_q->tx_count_frames = 0;
 		stmmac_set_tx_ic(priv, desc);
 		priv->xstats.tx_set_ic_bit++;
-	} else {
-		stmmac_tx_timer_arm(priv, queue);
 	}
 
 	/* We've used all descriptors we need for this skb, however,
@@ -3366,6 +3363,7 @@ static netdev_tx_t stmmac_xmit(struct sk_buff *skb, struct net_device *dev)
 
 	tx_q->tx_tail_addr = tx_q->dma_tx_phy + (tx_q->cur_tx * sizeof(*desc));
 	stmmac_set_tx_tail_ptr(priv, priv->ioaddr, tx_q->tx_tail_addr, queue);
+	stmmac_tx_timer_arm(priv, queue);
 
 	return NETDEV_TX_OK;
 
-- 
2.7.4