target/linux/layerscape/patches-5.4/701-net-0271-net-mscc-ocelot-use-skb-queue-instead-of-skbs-list.patch

   1 From e7e0b3b89da97e3186fbe3774a1ca9b77402d893 Mon Sep 17 00:00:00 2001
   2 From: Yangbo Lu <yangbo.lu@nxp.com>
   3 Date: Wed, 27 Nov 2019 15:27:57 +0800
   4 Subject: [PATCH] net: mscc: ocelot: use skb queue instead of skbs list
   5
   6 Convert to use skb queue instead of the list of skbs.
   7 The skb queue could provide protection with lock.
   8
   9 Signed-off-by: Yangbo Lu <yangbo.lu@nxp.com>
  10 Signed-off-by: David S. Miller <davem@davemloft.net>
  11 ---
  12  drivers/net/ethernet/mscc/ocelot.c | 54 +++++++++++++-------------------------
  13  include/soc/mscc/ocelot.h          |  9 +------
  14  2 files changed, 19 insertions(+), 44 deletions(-)
  15
  16 --- a/drivers/net/ethernet/mscc/ocelot.c
  17 +++ b/drivers/net/ethernet/mscc/ocelot.c
  18 @@ -583,18 +583,10 @@ int ocelot_port_add_txtstamp_skb(struct
  19
  20         if (ocelot->ptp && shinfo->tx_flags & SKBTX_HW_TSTAMP &&
  21             ocelot_port->ptp_cmd == IFH_REW_OP_TWO_STEP_PTP) {
  22 -               struct ocelot_skb *oskb =
  23 -                       kzalloc(sizeof(struct ocelot_skb), GFP_ATOMIC);
  24 -
  25 -               if (unlikely(!oskb))
  26 -                       return -ENOMEM;
  27 -
  28                 shinfo->tx_flags |= SKBTX_IN_PROGRESS;
  29 -
  30 -               oskb->skb = skb;
  31 -               oskb->id = ocelot_port->ts_id % 4;
  32 -
  33 -               list_add_tail(&oskb->head, &ocelot_port->skbs);
  34 +               /* Store timestamp ID in cb[0] of sk_buff */
  35 +               skb->cb[0] = ocelot_port->ts_id % 4;
  36 +               skb_queue_tail(&ocelot_port->tx_skbs, skb);
  37                 return 0;
  38         }
  39         return -ENODATA;
  40 @@ -704,12 +696,11 @@ void ocelot_get_txtstamp(struct ocelot *
  41         int budget = OCELOT_PTP_QUEUE_SZ;
  42
  43         while (budget--) {
  44 +               struct sk_buff *skb, *skb_tmp, *skb_match = NULL;
  45                 struct skb_shared_hwtstamps shhwtstamps;
  46 -               struct list_head *pos, *tmp;
  47 -               struct sk_buff *skb = NULL;
  48 -               struct ocelot_skb *entry;
  49                 struct ocelot_port *port;
  50                 struct timespec64 ts;
  51 +               unsigned long flags;
  52                 u32 val, id, txport;
  53
  54                 val = ocelot_read(ocelot, SYS_PTP_STATUS);
  55 @@ -727,22 +718,22 @@ void ocelot_get_txtstamp(struct ocelot *
  56                 /* Retrieve its associated skb */
  57                 port = ocelot->ports[txport];
  58
  59 -               list_for_each_safe(pos, tmp, &port->skbs) {
  60 -                       entry = list_entry(pos, struct ocelot_skb, head);
  61 -                       if (entry->id != id)
  62 -                               continue;
  63 +               spin_lock_irqsave(&port->tx_skbs.lock, flags);
  64
  65 -                       skb = entry->skb;
  66 -
  67 -                       list_del(pos);
  68 -                       kfree(entry);
  69 +               skb_queue_walk_safe(&port->tx_skbs, skb, skb_tmp) {
  70 +                       if (skb->cb[0] != id)
  71 +                               continue;
  72 +                       __skb_unlink(skb, &port->tx_skbs);
  73 +                       skb_match = skb;
  74                         break;
  75                 }
  76
  77 +               spin_unlock_irqrestore(&port->tx_skbs.lock, flags);
  78 +
  79                 /* Next ts */
  80                 ocelot_write(ocelot, SYS_PTP_NXT_PTP_NXT, SYS_PTP_NXT);
  81
  82 -               if (unlikely(!skb))
  83 +               if (unlikely(!skb_match))
  84                         continue;
  85
  86                 /* Get the h/w timestamp */
  87 @@ -751,9 +742,9 @@ void ocelot_get_txtstamp(struct ocelot *
  88                 /* Set the timestamp into the skb */
  89                 memset(&shhwtstamps, 0, sizeof(shhwtstamps));
  90                 shhwtstamps.hwtstamp = ktime_set(ts.tv_sec, ts.tv_nsec);
  91 -               skb_tstamp_tx(skb, &shhwtstamps);
  92 +               skb_tstamp_tx(skb_match, &shhwtstamps);
  93
  94 -               dev_kfree_skb_any(skb);
  95 +               dev_kfree_skb_any(skb_match);
  96         }
  97  }
  98  EXPORT_SYMBOL(ocelot_get_txtstamp);
  99 @@ -2208,7 +2199,7 @@ void ocelot_init_port(struct ocelot *oce
 100  {
 101         struct ocelot_port *ocelot_port = ocelot->ports[port];
 102
 103 -       INIT_LIST_HEAD(&ocelot_port->skbs);
 104 +       skb_queue_head_init(&ocelot_port->tx_skbs);
 105
 106         /* Basic L2 initialization */
 107
 108 @@ -2493,9 +2484,7 @@ EXPORT_SYMBOL(ocelot_init);
 109
 110  void ocelot_deinit(struct ocelot *ocelot)
 111  {
 112 -       struct list_head *pos, *tmp;
 113         struct ocelot_port *port;
 114 -       struct ocelot_skb *entry;
 115         int i;
 116
 117         cancel_delayed_work(&ocelot->stats_work);
 118 @@ -2507,14 +2496,7 @@ void ocelot_deinit(struct ocelot *ocelot
 119
 120         for (i = 0; i < ocelot->num_phys_ports; i++) {
 121                 port = ocelot->ports[i];
 122 -
 123 -               list_for_each_safe(pos, tmp, &port->skbs) {
 124 -                       entry = list_entry(pos, struct ocelot_skb, head);
 125 -
 126 -                       list_del(pos);
 127 -                       dev_kfree_skb_any(entry->skb);
 128 -                       kfree(entry);
 129 -               }
 130 +               skb_queue_purge(&port->tx_skbs);
 131         }
 132  }
 133  EXPORT_SYMBOL(ocelot_deinit);
 134 --- a/include/soc/mscc/ocelot.h
 135 +++ b/include/soc/mscc/ocelot.h
 136 @@ -406,13 +406,6 @@ struct ocelot_ops {
 137         int (*reset)(struct ocelot *ocelot);
 138  };
 139
 140 -struct ocelot_skb {
 141 -       struct list_head head;
 142 -       struct sk_buff *skb;
 143 -       u8 id;
 144 -};
 145 -
 146 -
 147  struct ocelot_port {
 148         struct ocelot                   *ocelot;
 149
 150 @@ -425,7 +418,7 @@ struct ocelot_port {
 151         u16                             vid;
 152
 153         u8                              ptp_cmd;
 154 -       struct list_head                skbs;
 155 +       struct sk_buff_head             tx_skbs;
 156         u8                              ts_id;
 157  };
 158