mlx4_en: Coalescing target is equal for all mtu's

The interrupt moderation should not depend on number of incoming
bytes, but on number of incoming packets.
The previous scheme caused very high interrupts rate for small
messages when big MTU was configured.

Signed-off-by: Yevgeny Petrilin <yevgenyp@mellanox.co.il>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/mlx4/en_ethtool.c b/drivers/net/mlx4/en_ethtool.c
index 91d8116..091f990 100644 (file)
--- a/drivers/net/mlx4/en_ethtool.c
+++ b/drivers/net/mlx4/en_ethtool.c
@@ -268,8 +268,7 @@ static int mlx4_en_set_coalesce(struct net_device *dev,
 
        priv->rx_frames = (coal->rx_max_coalesced_frames ==
                           MLX4_EN_AUTO_CONF) ?
-                               MLX4_EN_RX_COAL_TARGET /
-                               priv->dev->mtu + 1 :
+                               MLX4_EN_RX_COAL_TARGET :
                                coal->rx_max_coalesced_frames;
        priv->rx_usecs = (coal->rx_coalesce_usecs ==
                          MLX4_EN_AUTO_CONF) ?

diff --git a/drivers/net/mlx4/en_netdev.c b/drivers/net/mlx4/en_netdev.c
index fea65e7..16a634f 100644 (file)
--- a/drivers/net/mlx4/en_netdev.c
+++ b/drivers/net/mlx4/en_netdev.c
@@ -372,7 +372,7 @@ static void mlx4_en_set_default_moderation(struct mlx4_en_priv *priv)
         *   satisfy our coelsing target.
         * - moder_time is set to a fixed value.
         */
-       priv->rx_frames = MLX4_EN_RX_COAL_TARGET / priv->dev->mtu + 1;
+       priv->rx_frames = MLX4_EN_RX_COAL_TARGET;
        priv->rx_usecs = MLX4_EN_RX_COAL_TIME;
        en_dbg(INTR, priv, "Default coalesing params for mtu:%d - "
                           "rx_frames:%d rx_usecs:%d\n",

diff --git a/drivers/net/mlx4/mlx4_en.h b/drivers/net/mlx4/mlx4_en.h
index 174ae86..fcbfcfc 100644 (file)
--- a/drivers/net/mlx4/mlx4_en.h
+++ b/drivers/net/mlx4/mlx4_en.h
@@ -143,8 +143,8 @@ enum {
 #define MLX4_EN_DEF_TX_RING_SIZE       1024
 #define MLX4_EN_DEF_RX_RING_SIZE       1024
 
-/* Target number of bytes to coalesce with interrupt moderation */
-#define MLX4_EN_RX_COAL_TARGET 0x20000
+/* Target number of packets to coalesce with interrupt moderation */
+#define MLX4_EN_RX_COAL_TARGET 44
 #define MLX4_EN_RX_COAL_TIME   0x10
 
 #define MLX4_EN_TX_COAL_PKTS   5