net: hns3: unify maybe_stop_tx for TSO and non-TSO case

Currently, maybe_stop_tx ops for TSO and non-TSO case share some BD
calculation code, so this patch unifies the maybe_stop_tx by removing
the maybe_stop_tx ops. skb_is_gso() can be used to differentiate the
case between TSO and non-TSO case if there is need to handle special
case for TSO case.

This patch also add tx_copy field in "ethtool --statistics" to help
better debug the performance issue caused by calling skb_copy.

Signed-off-by: Yunsheng Lin <linyunsheng@huawei.com>
Signed-off-by: Huazhong Tan <tanhuazhong@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/ethernet/hisilicon/hns3/hns3_enet.c b/drivers/net/ethernet/hisilicon/hns3/hns3_enet.c
index 96272e632afcecfade30a9950f2b58490e81c9c5..06dda77f7fb8cccc56ddff7ddfeec802ba2e2312 100644 (file)
--- a/drivers/net/ethernet/hisilicon/hns3/hns3_enet.c
+++ b/drivers/net/ethernet/hisilicon/hns3/hns3_enet.c
@@ -1154,64 +1154,48 @@ static int hns3_fill_desc(struct hns3_enet_ring *ring, void *priv,
        return 0;
 }
 
-static int hns3_nic_maybe_stop_tso(struct sk_buff **out_skb, int *bnum,
-                                  struct hns3_enet_ring *ring)
+static int hns3_nic_bd_num(struct sk_buff *skb)
 {
-       struct sk_buff *skb = *out_skb;
-       struct sk_buff *new_skb = NULL;
-       struct skb_frag_struct *frag;
-       int bdnum_for_frag;
-       int frag_num;
-       int buf_num;
-       int size;
-       int i;
+       int size = skb_headlen(skb);
+       int i, bd_num;
 
-       size = skb_headlen(skb);
-       buf_num = hns3_tx_bd_count(size);
+       /* if the total len is within the max bd limit */
+       if (likely(skb->len <= HNS3_MAX_BD_SIZE))
+               return skb_shinfo(skb)->nr_frags + 1;
 
-       frag_num = skb_shinfo(skb)->nr_frags;
-       for (i = 0; i < frag_num; i++) {
-               frag = &skb_shinfo(skb)->frags[i];
-               size = skb_frag_size(frag);
-               bdnum_for_frag = hns3_tx_bd_count(size);
-               if (unlikely(bdnum_for_frag > HNS3_MAX_BD_PER_FRAG))
-                       return -ENOMEM;
+       bd_num = hns3_tx_bd_count(size);
 
-               buf_num += bdnum_for_frag;
-       }
+       for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
+               struct skb_frag_struct *frag = &skb_shinfo(skb)->frags[i];
+               int frag_bd_num;
 
-       if (unlikely(buf_num > HNS3_MAX_BD_PER_FRAG)) {
-               buf_num = hns3_tx_bd_count(skb->len);
-               if (ring_space(ring) < buf_num)
-                       return -EBUSY;
-               /* manual split the send packet */
-               new_skb = skb_copy(skb, GFP_ATOMIC);
-               if (!new_skb)
+               size = skb_frag_size(frag);
+               frag_bd_num = hns3_tx_bd_count(size);
+
+               if (unlikely(frag_bd_num > HNS3_MAX_BD_PER_FRAG))
                        return -ENOMEM;
-               dev_kfree_skb_any(skb);
-               *out_skb = new_skb;
-       }
 
-       if (unlikely(ring_space(ring) < buf_num))
-               return -EBUSY;
+               bd_num += frag_bd_num;
+       }
 
-       *bnum = buf_num;
-       return 0;
+       return bd_num;
 }
 
-static int hns3_nic_maybe_stop_tx(struct sk_buff **out_skb, int *bnum,
-                                 struct hns3_enet_ring *ring)
+static int hns3_nic_maybe_stop_tx(struct hns3_enet_ring *ring,
+                                 struct sk_buff **out_skb)
 {
        struct sk_buff *skb = *out_skb;
-       struct sk_buff *new_skb = NULL;
-       int buf_num;
+       int bd_num;
 
-       /* No. of segments (plus a header) */
-       buf_num = skb_shinfo(skb)->nr_frags + 1;
+       bd_num = hns3_nic_bd_num(skb);
+       if (bd_num < 0)
+               return bd_num;
+
+       if (unlikely(bd_num > HNS3_MAX_BD_PER_FRAG)) {
+               struct sk_buff *new_skb;
 
-       if (unlikely(buf_num > HNS3_MAX_BD_PER_FRAG)) {
-               buf_num = hns3_tx_bd_count(skb->len);
-               if (ring_space(ring) < buf_num)
+               bd_num = hns3_tx_bd_count(skb->len);
+               if (unlikely(ring_space(ring) < bd_num))
                        return -EBUSY;
                /* manual split the send packet */
                new_skb = skb_copy(skb, GFP_ATOMIC);
@@ -1219,14 +1203,16 @@ static int hns3_nic_maybe_stop_tx(struct sk_buff **out_skb, int *bnum,
                        return -ENOMEM;
                dev_kfree_skb_any(skb);
                *out_skb = new_skb;
+
+               u64_stats_update_begin(&ring->syncp);
+               ring->stats.tx_copy++;
+               u64_stats_update_end(&ring->syncp);
        }
 
-       if (unlikely(ring_space(ring) < buf_num))
+       if (unlikely(ring_space(ring) < bd_num))
                return -EBUSY;
 
-       *bnum = buf_num;
-
-       return 0;
+       return bd_num;
 }
 
 static void hns3_clear_desc(struct hns3_enet_ring *ring, int next_to_use_orig)
@@ -1277,22 +1263,23 @@ netdev_tx_t hns3_nic_net_xmit(struct sk_buff *skb, struct net_device *netdev)
        /* Prefetch the data used later */
        prefetch(skb->data);
 
-       switch (priv->ops.maybe_stop_tx(&skb, &buf_num, ring)) {
-       case -EBUSY:
-               u64_stats_update_begin(&ring->syncp);
-               ring->stats.tx_busy++;
-               u64_stats_update_end(&ring->syncp);
+       buf_num = hns3_nic_maybe_stop_tx(ring, &skb);
+       if (unlikely(buf_num <= 0)) {
+               if (buf_num == -EBUSY) {
+                       u64_stats_update_begin(&ring->syncp);
+                       ring->stats.tx_busy++;
+                       u64_stats_update_end(&ring->syncp);
+                       goto out_net_tx_busy;
+               } else if (buf_num == -ENOMEM) {
+                       u64_stats_update_begin(&ring->syncp);
+                       ring->stats.sw_err_cnt++;
+                       u64_stats_update_end(&ring->syncp);
+               }
 
-               goto out_net_tx_busy;
-       case -ENOMEM:
-               u64_stats_update_begin(&ring->syncp);
-               ring->stats.sw_err_cnt++;
-               u64_stats_update_end(&ring->syncp);
-               netdev_err(netdev, "no memory to xmit!\n");
+               if (net_ratelimit())
+                       netdev_err(netdev, "xmit error: %d!\n", buf_num);
 
                goto out_err_tx_ok;
-       default:
-               break;
        }
 
        /* No. of segments (plus a header) */
@@ -1397,13 +1384,6 @@ static int hns3_nic_set_features(struct net_device *netdev,
        bool enable;
        int ret;
 
-       if (changed & (NETIF_F_TSO | NETIF_F_TSO6)) {
-               if (features & (NETIF_F_TSO | NETIF_F_TSO6))
-                       priv->ops.maybe_stop_tx = hns3_nic_maybe_stop_tso;
-               else
-                       priv->ops.maybe_stop_tx = hns3_nic_maybe_stop_tx;
-       }
-
        if (changed & (NETIF_F_GRO_HW) && h->ae_algo->ops->set_gro_en) {
                enable = !!(features & NETIF_F_GRO_HW);
                ret = h->ae_algo->ops->set_gro_en(h, enable);
@@ -3733,17 +3713,6 @@ static void hns3_del_all_fd_rules(struct net_device *netdev, bool clear_list)
                h->ae_algo->ops->del_all_fd_entries(h, clear_list);
 }
 
-static void hns3_nic_set_priv_ops(struct net_device *netdev)
-{
-       struct hns3_nic_priv *priv = netdev_priv(netdev);
-
-       if ((netdev->features & NETIF_F_TSO) ||
-           (netdev->features & NETIF_F_TSO6))
-               priv->ops.maybe_stop_tx = hns3_nic_maybe_stop_tso;
-       else
-               priv->ops.maybe_stop_tx = hns3_nic_maybe_stop_tx;
-}
-
 static int hns3_client_start(struct hnae3_handle *handle)
 {
        if (!handle->ae_algo->ops->client_start)
@@ -3810,7 +3779,6 @@ static int hns3_client_init(struct hnae3_handle *handle)
        netdev->netdev_ops = &hns3_nic_netdev_ops;
        SET_NETDEV_DEV(netdev, &pdev->dev);
        hns3_ethtool_set_ops(netdev);
-       hns3_nic_set_priv_ops(netdev);
 
        /* Carrier off reporting is important to ethtool even BEFORE open */
        netif_carrier_off(netdev);

diff --git a/drivers/net/ethernet/hisilicon/hns3/hns3_enet.h b/drivers/net/ethernet/hisilicon/hns3/hns3_enet.h
index 2b4f5ea3fddf1ecda0f4199e047198d70545ea45..f669412764f2a128e57b9bf2e5c30927f13dfd56 100644 (file)
--- a/drivers/net/ethernet/hisilicon/hns3/hns3_enet.h
+++ b/drivers/net/ethernet/hisilicon/hns3/hns3_enet.h
@@ -376,6 +376,7 @@ struct ring_stats {
                        u64 tx_err_cnt;
                        u64 restart_queue;
                        u64 tx_busy;
+                       u64 tx_copy;
                };
                struct {
                        u64 rx_pkts;
@@ -444,11 +445,6 @@ struct hns3_nic_ring_data {
        void (*fini_process)(struct hns3_nic_ring_data *);
 };
 
-struct hns3_nic_ops {
-       int (*maybe_stop_tx)(struct sk_buff **out_skb,
-                            int *bnum, struct hns3_enet_ring *ring);
-};
-
 enum hns3_flow_level_range {
        HNS3_FLOW_LOW = 0,
        HNS3_FLOW_MID = 1,
@@ -538,7 +534,6 @@ struct hns3_nic_priv {
        u32 port_id;
        struct net_device *netdev;
        struct device *dev;
-       struct hns3_nic_ops ops;
 
        /**
         * the cb for nic to manage the ring buffer, the first half of the

diff --git a/drivers/net/ethernet/hisilicon/hns3/hns3_ethtool.c b/drivers/net/ethernet/hisilicon/hns3/hns3_ethtool.c
index 1746943083eab63cb4d7e4a78c5cf5c03ec17587..7256ed401d28a85d8d7ca6536ec37805adaf985c 100644 (file)
--- a/drivers/net/ethernet/hisilicon/hns3/hns3_ethtool.c
+++ b/drivers/net/ethernet/hisilicon/hns3/hns3_ethtool.c
@@ -29,6 +29,7 @@ static const struct hns3_stats hns3_txq_stats[] = {
        HNS3_TQP_STAT("errors", tx_err_cnt),
        HNS3_TQP_STAT("wake", restart_queue),
        HNS3_TQP_STAT("busy", tx_busy),
+       HNS3_TQP_STAT("copy", tx_copy),
 };
 
 #define HNS3_TXQ_STATS_COUNT ARRAY_SIZE(hns3_txq_stats)