target/linux/bcm63xx/patches-5.4/043-v5.12-bcm63xx_enet-alloc-rx-skb-with-NET_IP_ALIGN.patch

   1 From c4a207865e7ea310dc146ff4aa1b0aa0c78d3fe1 Mon Sep 17 00:00:00 2001
   2 From: Sieng Piaw Liew <liew.s.piaw@gmail.com>
   3 Date: Wed, 6 Jan 2021 22:42:05 +0800
   4 Subject: [PATCH 4/7] bcm63xx_enet: alloc rx skb with NET_IP_ALIGN
   5
   6 Use netdev_alloc_skb_ip_align on newer SoCs with integrated switch
   7 (enetsw) when refilling RX. Increases packet processing performance
   8 by 30% (with netif_receive_skb_list).
   9
  10 Non-enetsw SoCs cannot function with the extra pad so continue to use
  11 the regular netdev_alloc_skb.
  12
  13 Tested on BCM6328 320 MHz and iperf3 -M 512 to measure packet/sec
  14 performance.
  15
  16 Before:
  17 [ ID] Interval Transfer Bandwidth Retr
  18 [ 4] 0.00-30.00 sec 120 MBytes 33.7 Mbits/sec 277 sender
  19 [ 4] 0.00-30.00 sec 120 MBytes 33.5 Mbits/sec receiver
  20
  21 After (+netif_receive_skb_list):
  22 [ 4] 0.00-30.00 sec 155 MBytes 43.3 Mbits/sec 354 sender
  23 [ 4] 0.00-30.00 sec 154 MBytes 43.1 Mbits/sec receiver
  24
  25 Signed-off-by: Sieng Piaw Liew <liew.s.piaw@gmail.com>
  26 Acked-by: Florian Fainelli <f.fainelli@gmail.com>
  27 Signed-off-by: Jakub Kicinski <kuba@kernel.org>
  28 ---
  29  drivers/net/ethernet/broadcom/bcm63xx_enet.c | 5 ++++-
  30  1 file changed, 4 insertions(+), 1 deletion(-)
  31
  32 --- a/drivers/net/ethernet/broadcom/bcm63xx_enet.c
  33 +++ b/drivers/net/ethernet/broadcom/bcm63xx_enet.c
  34 @@ -238,7 +238,10 @@ static int bcm_enet_refill_rx(struct net
  35                 desc = &priv->rx_desc_cpu[desc_idx];
  36
  37                 if (!priv->rx_skb[desc_idx]) {
  38 -                       skb = netdev_alloc_skb(dev, priv->rx_skb_size);
  39 +                       if (priv->enet_is_sw)
  40 +                               skb = netdev_alloc_skb_ip_align(dev, priv->rx_skb_size);
  41 +                       else
  42 +                               skb = netdev_alloc_skb(dev, priv->rx_skb_size);
  43                         if (!skb)
  44                                 break;
  45                         priv->rx_skb[desc_idx] = skb;