net/mlx4_en: Add NAPI support for transmit side

Add NAPI for TX side,
implement its support and provide NAPI callback.

Signed-off-by: Yevgeny Petrilin <yevgenyp@mellanox.com>
Signed-off-by: Eugenia Emantayev <eugenia@mellanox.com>
Signed-off-by: Amir Vadai <amirv@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

3 files changed, 41 insertions, 11 deletions

diff --git a/drivers/net/ethernet/mellanox/mlx4/en_cq.c b/drivers/net/ethernet/mellanox/mlx4/en_cq.c
index 3a098cc4d349..70e95324a97d 100644
--- a/drivers/net/ethernet/mellanox/mlx4/en_cq.c
+++ b/drivers/net/ethernet/mellanox/mlx4/en_cq.c
@@ -161,12 +161,16 @@ int mlx4_en_activate_cq(struct mlx4_en_priv *priv, struct mlx4_en_cq *cq,
         cq->mcq.comp  = cq->is_tx ? mlx4_en_tx_irq : mlx4_en_rx_irq;
         cq->mcq.event = mlx4_en_cq_event;
 
-        if (!cq->is_tx) {
+        if (cq->is_tx) {
+                netif_napi_add(cq->dev, &cq->napi, mlx4_en_poll_tx_cq,
+                               NAPI_POLL_WEIGHT);
+        } else {
                 netif_napi_add(cq->dev, &cq->napi, mlx4_en_poll_rx_cq, 64);
                 napi_hash_add(&cq->napi);
-                napi_enable(&cq->napi);
         }
 
+        napi_enable(&cq->napi);
+
         return 0;
 }
 
@@ -188,12 +192,12 @@ void mlx4_en_destroy_cq(struct mlx4_en_priv *priv, struct mlx4_en_cq **pcq)
 
 void mlx4_en_deactivate_cq(struct mlx4_en_priv *priv, struct mlx4_en_cq *cq)
 {
+        napi_disable(&cq->napi);
         if (!cq->is_tx) {
-                napi_disable(&cq->napi);
                 napi_hash_del(&cq->napi);
                 synchronize_rcu();
-                netif_napi_del(&cq->napi);
         }
+        netif_napi_del(&cq->napi);
 
         mlx4_cq_free(priv->mdev->dev, &cq->mcq);
 }
diff --git a/drivers/net/ethernet/mellanox/mlx4/en_tx.c b/drivers/net/ethernet/mellanox/mlx4/en_tx.c
index 5e22d7d46b50..e3adcebfdfb8 100644
--- a/drivers/net/ethernet/mellanox/mlx4/en_tx.c
+++ b/drivers/net/ethernet/mellanox/mlx4/en_tx.c
@@ -324,7 +324,7 @@ static u32 mlx4_en_free_tx_desc(struct mlx4_en_priv *priv,
                         }
                 }
         }
-        dev_kfree_skb_any(skb);
+        dev_kfree_skb(skb);
         return tx_info->nr_txbb;
 }
 
@@ -361,7 +361,9 @@ int mlx4_en_free_tx_buf(struct net_device *dev, struct mlx4_en_tx_ring *ring)
         return cnt;
 }
 
-static void mlx4_en_process_tx_cq(struct net_device *dev, struct mlx4_en_cq *cq)
+static int mlx4_en_process_tx_cq(struct net_device *dev,
+                                 struct mlx4_en_cq *cq,
+                                 int budget)
 {
         struct mlx4_en_priv *priv = netdev_priv(dev);
         struct mlx4_cq *mcq = &cq->mcq;
@@ -379,9 +381,10 @@ static void mlx4_en_process_tx_cq(struct net_device *dev, struct mlx4_en_cq *cq)
         u32 bytes = 0;
         int factor = priv->cqe_factor;
         u64 timestamp = 0;
+        int done = 0;
 
         if (!priv->port_up)
-                return;
+                return 0;
 
         index = cons_index & size_mask;
         cqe = &buf[(index << factor) + factor];
@@ -390,7 +393,7 @@ static void mlx4_en_process_tx_cq(struct net_device *dev, struct mlx4_en_cq *cq)
 
         /* Process all completed CQEs */
         while (XNOR(cqe->owner_sr_opcode & MLX4_CQE_OWNER_MASK,
-                        cons_index & size)) {
+                        cons_index & size) && (done < budget)) {
                 /*
                  * make sure we read the CQE after we read the
                  * ownership bit
@@ -428,7 +431,7 @@ static void mlx4_en_process_tx_cq(struct net_device *dev, struct mlx4_en_cq *cq)
                         txbbs_stamp = txbbs_skipped;
                         packets++;
                         bytes += ring->tx_info[ring_index].nr_bytes;
-                } while (ring_index != new_index);
+                } while ((++done < budget) && (ring_index != new_index));
 
                 ++cons_index;
                 index = cons_index & size_mask;
@@ -454,6 +457,7 @@ static void mlx4_en_process_tx_cq(struct net_device *dev, struct mlx4_en_cq *cq)
                 netif_tx_wake_queue(ring->tx_queue);
                 priv->port_stats.wake_queue++;
         }
+        return done;
 }
 
 void mlx4_en_tx_irq(struct mlx4_cq *mcq)
@@ -461,10 +465,31 @@ void mlx4_en_tx_irq(struct mlx4_cq *mcq)
         struct mlx4_en_cq *cq = container_of(mcq, struct mlx4_en_cq, mcq);
         struct mlx4_en_priv *priv = netdev_priv(cq->dev);
 
-        mlx4_en_process_tx_cq(cq->dev, cq);
-        mlx4_en_arm_cq(priv, cq);
+        if (priv->port_up)
+                napi_schedule(&cq->napi);
+        else
+                mlx4_en_arm_cq(priv, cq);
 }
 
+/* TX CQ polling - called by NAPI */
+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;
+
+        done = mlx4_en_process_tx_cq(dev, cq, 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;
+}
 
 static struct mlx4_en_tx_desc *mlx4_en_bounce_to_desc(struct mlx4_en_priv *priv,
                                                       struct mlx4_en_tx_ring *ring,
diff --git a/drivers/net/ethernet/mellanox/mlx4/mlx4_en.h b/drivers/net/ethernet/mellanox/mlx4/mlx4_en.h
index 202d8e5eb41f..123714cbd35f 100644
--- a/drivers/net/ethernet/mellanox/mlx4/mlx4_en.h
+++ b/drivers/net/ethernet/mellanox/mlx4/mlx4_en.h
@@ -744,6 +744,7 @@ int mlx4_en_process_rx_cq(struct net_device *dev,
                           struct mlx4_en_cq *cq,
                           int budget);
 int mlx4_en_poll_rx_cq(struct napi_struct *napi, int budget);
+int mlx4_en_poll_tx_cq(struct napi_struct *napi, int budget);
 void mlx4_en_fill_qp_context(struct mlx4_en_priv *priv, int size, int stride,
                 int is_tx, int rss, int qpn, int cqn, int user_prio,
                 struct mlx4_qp_context *context);