diff options
| -rw-r--r-- | drivers/net/ethernet/mellanox/mlx4/en_tx.c | 67 |
1 files changed, 38 insertions, 29 deletions
diff --git a/drivers/net/ethernet/mellanox/mlx4/en_tx.c b/drivers/net/ethernet/mellanox/mlx4/en_tx.c index 2c03b5520483..f0080c5417c3 100644 --- a/drivers/net/ethernet/mellanox/mlx4/en_tx.c +++ b/drivers/net/ethernet/mellanox/mlx4/en_tx.c @@ -531,29 +531,32 @@ static struct mlx4_en_tx_desc *mlx4_en_bounce_to_desc(struct mlx4_en_priv *priv, return ring->buf + index * TXBB_SIZE; } +/* Decide if skb can be inlined in tx descriptor to avoid dma mapping + * + * It seems strange we do not simply use skb_copy_bits(). + * This would allow to inline all skbs iff skb->len <= inline_thold + * + * Note that caller already checked skb was not a gso packet + */ static bool is_inline(int inline_thold, const struct sk_buff *skb, const struct skb_shared_info *shinfo, void **pfrag) { void *ptr; - if (inline_thold && !skb_is_gso(skb) && skb->len <= inline_thold) { - if (shinfo->nr_frags == 1) { - ptr = skb_frag_address_safe(&shinfo->frags[0]); - if (unlikely(!ptr)) - return 0; - - if (pfrag) - *pfrag = ptr; + if (skb->len > inline_thold || !inline_thold) + return false; - return 1; - } else if (unlikely(shinfo->nr_frags)) - return 0; - else - return 1; + if (shinfo->nr_frags == 1) { + ptr = skb_frag_address_safe(&shinfo->frags[0]); + if (unlikely(!ptr)) + return false; + *pfrag = ptr; + return true; } - - return 0; + if (shinfo->nr_frags) + return false; + return true; } static int inline_size(const struct sk_buff *skb) @@ -570,12 +573,15 @@ static int inline_size(const struct sk_buff *skb) static int get_real_size(const struct sk_buff *skb, const struct skb_shared_info *shinfo, struct net_device *dev, - int *lso_header_size) + int *lso_header_size, + bool *inline_ok, + void **pfrag) { struct mlx4_en_priv *priv = netdev_priv(dev); int real_size; if (shinfo->gso_size) { + *inline_ok = false; if (skb->encapsulation) *lso_header_size = (skb_inner_transport_header(skb) - skb->data) + inner_tcp_hdrlen(skb); else @@ -595,10 +601,14 @@ static int get_real_size(const struct sk_buff *skb, } } else { *lso_header_size = 0; - if (!is_inline(priv->prof->inline_thold, skb, shinfo, NULL)) - real_size = CTRL_SIZE + (shinfo->nr_frags + 1) * DS_SIZE; - else + *inline_ok = is_inline(priv->prof->inline_thold, skb, + shinfo, pfrag); + + if (*inline_ok) real_size = inline_size(skb); + else + real_size = CTRL_SIZE + + (shinfo->nr_frags + 1) * DS_SIZE; } return real_size; @@ -694,9 +704,10 @@ netdev_tx_t mlx4_en_xmit(struct sk_buff *skb, struct net_device *dev) u16 vlan_tag = 0; int i_frag; int lso_header_size; - void *fragptr; + void *fragptr = NULL; bool bounce = false; bool send_doorbell; + bool inline_ok; u32 ring_cons; if (!priv->port_up) @@ -708,7 +719,8 @@ netdev_tx_t mlx4_en_xmit(struct sk_buff *skb, struct net_device *dev) /* fetch ring->cons far ahead before needing it to avoid stall */ ring_cons = ACCESS_ONCE(ring->cons); - real_size = get_real_size(skb, shinfo, dev, &lso_header_size); + real_size = get_real_size(skb, shinfo, dev, &lso_header_size, + &inline_ok, &fragptr); if (unlikely(!real_size)) goto tx_drop; @@ -781,15 +793,15 @@ netdev_tx_t mlx4_en_xmit(struct sk_buff *skb, struct net_device *dev) /* valid only for none inline segments */ tx_info->data_offset = (void *)data - (void *)tx_desc; + tx_info->inl = inline_ok; + tx_info->linear = (lso_header_size < skb_headlen(skb) && - !is_inline(ring->inline_thold, skb, shinfo, NULL)) ? 1 : 0; + !inline_ok) ? 1 : 0; tx_info->nr_maps = shinfo->nr_frags + tx_info->linear; data += tx_info->nr_maps - 1; - if (is_inline(ring->inline_thold, skb, shinfo, &fragptr)) { - tx_info->inl = 1; - } else { + if (!tx_info->inl) { dma_addr_t dma = 0; u32 byte_count = 0; @@ -827,7 +839,6 @@ netdev_tx_t mlx4_en_xmit(struct sk_buff *skb, struct net_device *dev) wmb(); data->byte_count = cpu_to_be32(byte_count); } - tx_info->inl = 0; /* tx completion can avoid cache line miss for common cases */ tx_info->map0_dma = dma; tx_info->map0_byte_count = byte_count; @@ -899,11 +910,9 @@ netdev_tx_t mlx4_en_xmit(struct sk_buff *skb, struct net_device *dev) netdev_tx_sent_queue(ring->tx_queue, tx_info->nr_bytes); AVG_PERF_COUNTER(priv->pstats.tx_pktsz_avg, skb->len); - if (tx_info->inl) { + if (tx_info->inl) build_inline_wqe(tx_desc, skb, shinfo, real_size, &vlan_tag, tx_ind, fragptr); - tx_info->inl = 1; - } if (skb->encapsulation) { struct iphdr *ipv4 = (struct iphdr *)skb_inner_network_header(skb); |