mlx4: exploit skb->xmit_more to conditionally send doorbell
authorEric Dumazet <edumazet@google.com>
Thu, 25 Sep 2014 14:17:49 +0000 (07:17 -0700)
committerDavid S. Miller <davem@davemloft.net>
Sun, 28 Sep 2014 21:27:36 +0000 (17:27 -0400)
commit5804283d7cb1da46485950d545dd7869137dcda5
treeba4656cb940b502838058edbf81d15cf147d0171
parenta8404ce5ae7a6054322afb5aa77cefe3ad54475e
mlx4: exploit skb->xmit_more to conditionally send doorbell

skb->xmit_more tells us if another skb is coming next.

We need to send doorbell when : xmit_more is not set,
or txqueue is stopped (preventing next skb to come immediately)

Tested with a modified pktgen version, I got a 40% increase of
throughput.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
drivers/net/ethernet/mellanox/mlx4/en_tx.c