From: Yevgeny Petrilin Date: Mon, 23 Apr 2012 02:18:39 +0000 (+0000) Subject: mlx4_en: Moving to Interrupts for TX completions X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=e22979d96a55d;p=linux-beck.git mlx4_en: Moving to Interrupts for TX completions Moving to interrupts instead of polling fpr TX completions Avoiding situations where skb can be held in by the driver for a long time (till timer expires). The change is also necessary for supporting BQL. Removing comp_lock that was required because we could handle TX completions from several contexts: Interrupts, timer, polling. Now there is only interrupts Signed-off-by: Yevgeny Petrilin Signed-off-by: David S. Miller --- diff --git a/drivers/net/ethernet/mellanox/mlx4/en_cq.c b/drivers/net/ethernet/mellanox/mlx4/en_cq.c index 00b81272e314..908a460d8db6 100644 --- a/drivers/net/ethernet/mellanox/mlx4/en_cq.c +++ b/drivers/net/ethernet/mellanox/mlx4/en_cq.c @@ -124,11 +124,7 @@ 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) { - init_timer(&cq->timer); - cq->timer.function = mlx4_en_poll_tx_cq; - cq->timer.data = (unsigned long) cq; - } else { + if (!cq->is_tx) { netif_napi_add(cq->dev, &cq->napi, mlx4_en_poll_rx_cq, 64); napi_enable(&cq->napi); } @@ -151,16 +147,12 @@ void mlx4_en_destroy_cq(struct mlx4_en_priv *priv, struct mlx4_en_cq *cq) void mlx4_en_deactivate_cq(struct mlx4_en_priv *priv, struct mlx4_en_cq *cq) { - struct mlx4_en_dev *mdev = priv->mdev; - - if (cq->is_tx) - del_timer(&cq->timer); - else { + if (!cq->is_tx) { napi_disable(&cq->napi); netif_napi_del(&cq->napi); } - mlx4_cq_free(mdev->dev, &cq->mcq); + mlx4_cq_free(priv->mdev->dev, &cq->mcq); } /* Set rx cq moderation parameters */ diff --git a/drivers/net/ethernet/mellanox/mlx4/en_netdev.c b/drivers/net/ethernet/mellanox/mlx4/en_netdev.c index bfcfd8ae5f73..35ad0971939d 100644 --- a/drivers/net/ethernet/mellanox/mlx4/en_netdev.c +++ b/drivers/net/ethernet/mellanox/mlx4/en_netdev.c @@ -667,6 +667,10 @@ int mlx4_en_start_port(struct net_device *dev) mlx4_en_deactivate_cq(priv, cq); goto tx_err; } + + /* Arm CQ for TX completions */ + mlx4_en_arm_cq(priv, cq); + /* Set initial ownership of all Tx TXBBs to SW (1) */ for (j = 0; j < tx_ring->buf_size; j += STAMP_STRIDE) *((u32 *) (tx_ring->buf + j)) = 0xffffffff; diff --git a/drivers/net/ethernet/mellanox/mlx4/en_tx.c b/drivers/net/ethernet/mellanox/mlx4/en_tx.c index d9bab5338c2f..2d493420e1a6 100644 --- a/drivers/net/ethernet/mellanox/mlx4/en_tx.c +++ b/drivers/net/ethernet/mellanox/mlx4/en_tx.c @@ -67,8 +67,6 @@ int mlx4_en_create_tx_ring(struct mlx4_en_priv *priv, inline_thold = min(inline_thold, MAX_INLINE); - spin_lock_init(&ring->comp_lock); - tmp = size * sizeof(struct mlx4_en_tx_info); ring->tx_info = vmalloc(tmp); if (!ring->tx_info) @@ -377,41 +375,12 @@ 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); - struct mlx4_en_tx_ring *ring = &priv->tx_ring[cq->ring]; - if (!spin_trylock(&ring->comp_lock)) - return; mlx4_en_process_tx_cq(cq->dev, cq); - mod_timer(&cq->timer, jiffies + 1); - spin_unlock(&ring->comp_lock); + mlx4_en_arm_cq(priv, cq); } -void mlx4_en_poll_tx_cq(unsigned long data) -{ - struct mlx4_en_cq *cq = (struct mlx4_en_cq *) data; - struct mlx4_en_priv *priv = netdev_priv(cq->dev); - struct mlx4_en_tx_ring *ring = &priv->tx_ring[cq->ring]; - u32 inflight; - - INC_PERF_COUNTER(priv->pstats.tx_poll); - - if (!spin_trylock_irq(&ring->comp_lock)) { - mod_timer(&cq->timer, jiffies + MLX4_EN_TX_POLL_TIMEOUT); - return; - } - mlx4_en_process_tx_cq(cq->dev, cq); - inflight = (u32) (ring->prod - ring->cons - ring->last_nr_txbb); - - /* If there are still packets in flight and the timer has not already - * been scheduled by the Tx routine then schedule it here to guarantee - * completion processing of these packets */ - if (inflight && priv->port_up) - mod_timer(&cq->timer, jiffies + MLX4_EN_TX_POLL_TIMEOUT); - - spin_unlock_irq(&ring->comp_lock); -} - static struct mlx4_en_tx_desc *mlx4_en_bounce_to_desc(struct mlx4_en_priv *priv, struct mlx4_en_tx_ring *ring, u32 index, @@ -440,25 +409,6 @@ static struct mlx4_en_tx_desc *mlx4_en_bounce_to_desc(struct mlx4_en_priv *priv, return ring->buf + index * TXBB_SIZE; } -static inline void mlx4_en_xmit_poll(struct mlx4_en_priv *priv, int tx_ind) -{ - struct mlx4_en_cq *cq = &priv->tx_cq[tx_ind]; - struct mlx4_en_tx_ring *ring = &priv->tx_ring[tx_ind]; - unsigned long flags; - - /* If we don't have a pending timer, set one up to catch our recent - post in case the interface becomes idle */ - if (!timer_pending(&cq->timer)) - mod_timer(&cq->timer, jiffies + MLX4_EN_TX_POLL_TIMEOUT); - - /* Poll the CQ every mlx4_en_TX_MODER_POLL packets */ - if ((++ring->poll_cnt & (MLX4_EN_TX_POLL_MODER - 1)) == 0) - if (spin_trylock_irqsave(&ring->comp_lock, flags)) { - mlx4_en_process_tx_cq(priv->dev, cq); - spin_unlock_irqrestore(&ring->comp_lock, flags); - } -} - static int is_inline(struct sk_buff *skb, void **pfrag) { void *ptr; @@ -590,7 +540,6 @@ netdev_tx_t mlx4_en_xmit(struct sk_buff *skb, struct net_device *dev) struct mlx4_en_priv *priv = netdev_priv(dev); struct mlx4_en_dev *mdev = priv->mdev; struct mlx4_en_tx_ring *ring; - struct mlx4_en_cq *cq; struct mlx4_en_tx_desc *tx_desc; struct mlx4_wqe_data_seg *data; struct skb_frag_struct *frag; @@ -638,9 +587,6 @@ netdev_tx_t mlx4_en_xmit(struct sk_buff *skb, struct net_device *dev) ring->blocked = 1; priv->port_stats.queue_stopped++; - /* Use interrupts to find out when queue opened */ - cq = &priv->tx_cq[tx_ind]; - mlx4_en_arm_cq(priv, cq); return NETDEV_TX_BUSY; } @@ -788,9 +734,6 @@ netdev_tx_t mlx4_en_xmit(struct sk_buff *skb, struct net_device *dev) iowrite32be(ring->doorbell_qpn, ring->bf.uar->map + MLX4_SEND_DOORBELL); } - /* Poll CQ here */ - mlx4_en_xmit_poll(priv, tx_ind); - return NETDEV_TX_OK; tx_drop: diff --git a/drivers/net/ethernet/mellanox/mlx4/mlx4_en.h b/drivers/net/ethernet/mellanox/mlx4/mlx4_en.h index 47e1c0ff1775..0feafc5344b3 100644 --- a/drivers/net/ethernet/mellanox/mlx4/mlx4_en.h +++ b/drivers/net/ethernet/mellanox/mlx4/mlx4_en.h @@ -122,7 +122,7 @@ enum { #define MLX4_EN_RX_COAL_TARGET 44 #define MLX4_EN_RX_COAL_TIME 0x10 -#define MLX4_EN_TX_COAL_PKTS 5 +#define MLX4_EN_TX_COAL_PKTS 16 #define MLX4_EN_TX_COAL_TIME 0x80 #define MLX4_EN_RX_RATE_LOW 400000 @@ -255,7 +255,6 @@ struct mlx4_en_tx_ring { unsigned long bytes; unsigned long packets; unsigned long tx_csum; - spinlock_t comp_lock; struct mlx4_bf bf; bool bf_enabled; }; @@ -308,8 +307,6 @@ struct mlx4_en_cq { spinlock_t lock; struct net_device *dev; struct napi_struct napi; - /* Per-core Tx cq processing support */ - struct timer_list timer; int size; int buf_size; unsigned vector; @@ -530,7 +527,6 @@ void mlx4_en_deactivate_cq(struct mlx4_en_priv *priv, struct mlx4_en_cq *cq); int mlx4_en_set_cq_moder(struct mlx4_en_priv *priv, struct mlx4_en_cq *cq); int mlx4_en_arm_cq(struct mlx4_en_priv *priv, struct mlx4_en_cq *cq); -void mlx4_en_poll_tx_cq(unsigned long data); void mlx4_en_tx_irq(struct mlx4_cq *mcq); u16 mlx4_en_select_queue(struct net_device *dev, struct sk_buff *skb); netdev_tx_t mlx4_en_xmit(struct sk_buff *skb, struct net_device *dev);