diff options
| author | Amir Vadai <amirv@mellanox.com> | 2014-07-08 11:28:12 +0300 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2014-07-08 20:00:49 -0700 |
| commit | fbc6daf19745b372c0d909e5d74ab02e42b70e51 (patch) | |
| tree | 261af07430baed5f056fde747f73e9f9879bf02c /drivers/net/ethernet/mellanox/mlx4/en_tx.c | |
| parent | 0b0302449110ca5ca4350458ed57b971fcb78ec1 (diff) | |
net/mlx4_en: Ignore budget on TX napi polling
It is recommended that TX work not count against the quota.
The cost of TX packet liberation is a minute percentage of what it costs to
process an RX frame. Furthermore, that SKB freeing makes memory available for
other paths in the stack.
Give the TX a larger budget and be more aggressive about cleaning up the Tx
descriptors this budget could be changed using ethtool:
$ ethtool -C eth1 tx-frames-irq <budget>
Signed-off-by: Amir Vadai <amirv@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'drivers/net/ethernet/mellanox/mlx4/en_tx.c')
| -rw-r--r-- | drivers/net/ethernet/mellanox/mlx4/en_tx.c | 28 |
1 files changed, 13 insertions, 15 deletions
diff --git a/drivers/net/ethernet/mellanox/mlx4/en_tx.c b/drivers/net/ethernet/mellanox/mlx4/en_tx.c index ac3dead3792c..5045bab59633 100644 --- a/drivers/net/ethernet/mellanox/mlx4/en_tx.c +++ b/drivers/net/ethernet/mellanox/mlx4/en_tx.c @@ -351,9 +351,8 @@ int mlx4_en_free_tx_buf(struct net_device *dev, struct mlx4_en_tx_ring *ring) return cnt; } -static int mlx4_en_process_tx_cq(struct net_device *dev, - struct mlx4_en_cq *cq, - int budget) +static bool mlx4_en_process_tx_cq(struct net_device *dev, + struct mlx4_en_cq *cq) { struct mlx4_en_priv *priv = netdev_priv(dev); struct mlx4_cq *mcq = &cq->mcq; @@ -372,9 +371,10 @@ static int mlx4_en_process_tx_cq(struct net_device *dev, int factor = priv->cqe_factor; u64 timestamp = 0; int done = 0; + int budget = priv->tx_work_limit; if (!priv->port_up) - return 0; + return true; index = cons_index & size_mask; cqe = &buf[(index << factor) + factor]; @@ -447,7 +447,7 @@ static int mlx4_en_process_tx_cq(struct net_device *dev, netif_tx_wake_queue(ring->tx_queue); ring->wake_queue++; } - return done; + return done < budget; } void mlx4_en_tx_irq(struct mlx4_cq *mcq) @@ -467,18 +467,16 @@ int mlx4_en_poll_tx_cq(struct napi_struct *napi, int budget) struct mlx4_en_cq *cq = container_of(napi, struct mlx4_en_cq, napi); struct net_device *dev = cq->dev; struct mlx4_en_priv *priv = netdev_priv(dev); - int done; + int clean_complete; - done = mlx4_en_process_tx_cq(dev, cq, budget); + clean_complete = mlx4_en_process_tx_cq(dev, cq); + if (!clean_complete) + return budget; - /* If we used up all the quota - we're probably not done yet... */ - if (done < budget) { - /* Done for now */ - napi_complete(napi); - mlx4_en_arm_cq(priv, cq); - return done; - } - return budget; + napi_complete(napi); + mlx4_en_arm_cq(priv, cq); + + return 0; } static struct mlx4_en_tx_desc *mlx4_en_bounce_to_desc(struct mlx4_en_priv *priv, |