tg3: Add skb->xmit_more support

Ring TX doorbell only if xmit_more is not set or the queue is stopped.

Suggested-by: Daniel Borkmann <dborkman@redhat.com>
Signed-off-by: Prashant Sreedharan <prashant@broadcom.com>
Signed-off-by: Michael Chan <mchan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 6 insertions, 4 deletions

diff --git a/drivers/net/ethernet/broadcom/tg3.c b/drivers/net/ethernet/broadcom/tg3.c
index ba499489969a..dbb41c1923e6 100644
--- a/drivers/net/ethernet/broadcom/tg3.c
+++ b/drivers/net/ethernet/broadcom/tg3.c
@@ -8099,9 +8099,6 @@ static netdev_tx_t tg3_start_xmit(struct sk_buff *skb, struct net_device *dev)
         /* Sync BD data before updating mailbox */
         wmb();
 
-        /* Packets are ready, update Tx producer idx local and on card. */
-        tw32_tx_mbox(tnapi->prodmbox, entry);
-
         tnapi->tx_prod = entry;
         if (unlikely(tg3_tx_avail(tnapi) <= (MAX_SKB_FRAGS + 1))) {
                 netif_tx_stop_queue(txq);
@@ -8116,7 +8113,12 @@ static netdev_tx_t tg3_start_xmit(struct sk_buff *skb, struct net_device *dev)
                         netif_tx_wake_queue(txq);
         }
 
-        mmiowb();
+        if (!skb->xmit_more || netif_xmit_stopped(txq)) {
+                /* Packets are ready, update Tx producer idx on card. */
+                tw32_tx_mbox(tnapi->prodmbox, entry);
+                mmiowb();
+        }
+
         return NETDEV_TX_OK;
 
 dma_error: