target/linux/mediatek/patches-4.4/0069-net-mediatek-fix-stop-and-wakeup-of-queue.patch

   1 From 6f8bfdfe2984467177d2a88982517659ec09ab5d Mon Sep 17 00:00:00 2001
   2 From: John Crispin <blogic@openwrt.org>
   3 Date: Tue, 29 Mar 2016 16:41:07 +0200
   4 Subject: [PATCH 69/81] net: mediatek: fix stop and wakeup of queue
   5
   6 The driver supports 2 MACs. Both run on the same DMA ring. If we go
   7 above/below the TX rings thershold value, we always need to wake/stop
   8 the queu of both devices. Not doing to can cause TX stalls and packet
   9 drops on one of the devices.
  10
  11 Signed-off-by: John Crispin <blogic@openwrt.org>
  12 ---
  13  drivers/net/ethernet/mediatek/mtk_eth_soc.c |   37 +++++++++++++++++++--------
  14  1 file changed, 27 insertions(+), 10 deletions(-)
  15
  16 diff --git a/drivers/net/ethernet/mediatek/mtk_eth_soc.c b/drivers/net/ethernet/mediatek/mtk_eth_soc.c
  17 index 293ea59..04bdb9d 100644
  18 --- a/drivers/net/ethernet/mediatek/mtk_eth_soc.c
  19 +++ b/drivers/net/ethernet/mediatek/mtk_eth_soc.c
  20 @@ -684,6 +684,28 @@ static inline int mtk_cal_txd_req(struct sk_buff *skb)
  21         return nfrags;
  22  }
  23
  24 +static void mtk_wake_queue(struct mtk_eth *eth)
  25 +{
  26 +       int i;
  27 +
  28 +       for (i = 0; i < MTK_MAC_COUNT; i++) {
  29 +               if (!eth->netdev[i])
  30 +                       continue;
  31 +               netif_wake_queue(eth->netdev[i]);
  32 +       }
  33 +}
  34 +
  35 +static void mtk_stop_queue(struct mtk_eth *eth)
  36 +{
  37 +       int i;
  38 +
  39 +       for (i = 0; i < MTK_MAC_COUNT; i++) {
  40 +               if (!eth->netdev[i])
  41 +                       continue;
  42 +               netif_stop_queue(eth->netdev[i]);
  43 +       }
  44 +}
  45 +
  46  static int mtk_start_xmit(struct sk_buff *skb, struct net_device *dev)
  47  {
  48         struct mtk_mac *mac = netdev_priv(dev);
  49 @@ -695,7 +717,7 @@ static int mtk_start_xmit(struct sk_buff *skb, struct net_device *dev)
  50
  51         tx_num = mtk_cal_txd_req(skb);
  52         if (unlikely(atomic_read(&ring->free_count) <= tx_num)) {
  53 -               netif_stop_queue(dev);
  54 +               mtk_stop_queue(eth);
  55                 netif_err(eth, tx_queued, dev,
  56                           "Tx Ring full when queue awake!\n");
  57                 return NETDEV_TX_BUSY;
  58 @@ -720,10 +742,10 @@ static int mtk_start_xmit(struct sk_buff *skb, struct net_device *dev)
  59                 goto drop;
  60
  61         if (unlikely(atomic_read(&ring->free_count) <= ring->thresh)) {
  62 -               netif_stop_queue(dev);
  63 +               mtk_stop_queue(eth);
  64                 if (unlikely(atomic_read(&ring->free_count) >
  65                              ring->thresh))
  66 -                       netif_wake_queue(dev);
  67 +                       mtk_wake_queue(eth);
  68         }
  69
  70         return NETDEV_TX_OK;
  71 @@ -897,13 +919,8 @@ static int mtk_poll_tx(struct mtk_eth *eth, int budget, bool *tx_again)
  72         if (!total)
  73                 return 0;
  74
  75 -       for (i = 0; i < MTK_MAC_COUNT; i++) {
  76 -               if (!eth->netdev[i] ||
  77 -                   unlikely(!netif_queue_stopped(eth->netdev[i])))
  78 -                       continue;
  79 -               if (atomic_read(&ring->free_count) > ring->thresh)
  80 -                       netif_wake_queue(eth->netdev[i]);
  81 -       }
  82 +       if (atomic_read(&ring->free_count) > ring->thresh)
  83 +               mtk_wake_queue(eth);
  84
  85         return total;
  86  }
  87 --
  88 1.7.10.4
  89