target/linux/generic/patches-4.9/662-remove_pfifo_fast.patch

   1 --- a/net/sched/sch_generic.c
   2 +++ b/net/sched/sch_generic.c
   3 @@ -449,146 +449,6 @@ struct Qdisc_ops noqueue_qdisc_ops __rea
   4         .owner          =       THIS_MODULE,
   5  };
   6
   7 -static const u8 prio2band[TC_PRIO_MAX + 1] = {
   8 -       1, 2, 2, 2, 1, 2, 0, 0 , 1, 1, 1, 1, 1, 1, 1, 1
   9 -};
  10 -
  11 -/* 3-band FIFO queue: old style, but should be a bit faster than
  12 -   generic prio+fifo combination.
  13 - */
  14 -
  15 -#define PFIFO_FAST_BANDS 3
  16 -
  17 -/*
  18 - * Private data for a pfifo_fast scheduler containing:
  19 - *     - queues for the three band
  20 - *     - bitmap indicating which of the bands contain skbs
  21 - */
  22 -struct pfifo_fast_priv {
  23 -       u32 bitmap;
  24 -       struct qdisc_skb_head q[PFIFO_FAST_BANDS];
  25 -};
  26 -
  27 -/*
  28 - * Convert a bitmap to the first band number where an skb is queued, where:
  29 - *     bitmap=0 means there are no skbs on any band.
  30 - *     bitmap=1 means there is an skb on band 0.
  31 - *     bitmap=7 means there are skbs on all 3 bands, etc.
  32 - */
  33 -static const int bitmap2band[] = {-1, 0, 1, 0, 2, 0, 1, 0};
  34 -
  35 -static inline struct qdisc_skb_head *band2list(struct pfifo_fast_priv *priv,
  36 -                                            int band)
  37 -{
  38 -       return priv->q + band;
  39 -}
  40 -
  41 -static int pfifo_fast_enqueue(struct sk_buff *skb, struct Qdisc *qdisc,
  42 -                             struct sk_buff **to_free)
  43 -{
  44 -       if (qdisc->q.qlen < qdisc_dev(qdisc)->tx_queue_len) {
  45 -               int band = prio2band[skb->priority & TC_PRIO_MAX];
  46 -               struct pfifo_fast_priv *priv = qdisc_priv(qdisc);
  47 -               struct qdisc_skb_head *list = band2list(priv, band);
  48 -
  49 -               priv->bitmap |= (1 << band);
  50 -               qdisc->q.qlen++;
  51 -               return __qdisc_enqueue_tail(skb, qdisc, list);
  52 -       }
  53 -
  54 -       return qdisc_drop(skb, qdisc, to_free);
  55 -}
  56 -
  57 -static struct sk_buff *pfifo_fast_dequeue(struct Qdisc *qdisc)
  58 -{
  59 -       struct pfifo_fast_priv *priv = qdisc_priv(qdisc);
  60 -       int band = bitmap2band[priv->bitmap];
  61 -
  62 -       if (likely(band >= 0)) {
  63 -               struct qdisc_skb_head *qh = band2list(priv, band);
  64 -               struct sk_buff *skb = __qdisc_dequeue_head(qh);
  65 -
  66 -               if (likely(skb != NULL)) {
  67 -                       qdisc_qstats_backlog_dec(qdisc, skb);
  68 -                       qdisc_bstats_update(qdisc, skb);
  69 -               }
  70 -
  71 -               qdisc->q.qlen--;
  72 -               if (qh->qlen == 0)
  73 -                       priv->bitmap &= ~(1 << band);
  74 -
  75 -               return skb;
  76 -       }
  77 -
  78 -       return NULL;
  79 -}
  80 -
  81 -static struct sk_buff *pfifo_fast_peek(struct Qdisc *qdisc)
  82 -{
  83 -       struct pfifo_fast_priv *priv = qdisc_priv(qdisc);
  84 -       int band = bitmap2band[priv->bitmap];
  85 -
  86 -       if (band >= 0) {
  87 -               struct qdisc_skb_head *qh = band2list(priv, band);
  88 -
  89 -               return qh->head;
  90 -       }
  91 -
  92 -       return NULL;
  93 -}
  94 -
  95 -static void pfifo_fast_reset(struct Qdisc *qdisc)
  96 -{
  97 -       int prio;
  98 -       struct pfifo_fast_priv *priv = qdisc_priv(qdisc);
  99 -
 100 -       for (prio = 0; prio < PFIFO_FAST_BANDS; prio++)
 101 -               __qdisc_reset_queue(band2list(priv, prio));
 102 -
 103 -       priv->bitmap = 0;
 104 -       qdisc->qstats.backlog = 0;
 105 -       qdisc->q.qlen = 0;
 106 -}
 107 -
 108 -static int pfifo_fast_dump(struct Qdisc *qdisc, struct sk_buff *skb)
 109 -{
 110 -       struct tc_prio_qopt opt = { .bands = PFIFO_FAST_BANDS };
 111 -
 112 -       memcpy(&opt.priomap, prio2band, TC_PRIO_MAX + 1);
 113 -       if (nla_put(skb, TCA_OPTIONS, sizeof(opt), &opt))
 114 -               goto nla_put_failure;
 115 -       return skb->len;
 116 -
 117 -nla_put_failure:
 118 -       return -1;
 119 -}
 120 -
 121 -static int pfifo_fast_init(struct Qdisc *qdisc, struct nlattr *opt)
 122 -{
 123 -       int prio;
 124 -       struct pfifo_fast_priv *priv = qdisc_priv(qdisc);
 125 -
 126 -       for (prio = 0; prio < PFIFO_FAST_BANDS; prio++)
 127 -               qdisc_skb_head_init(band2list(priv, prio));
 128 -
 129 -       /* Can by-pass the queue discipline */
 130 -       qdisc->flags |= TCQ_F_CAN_BYPASS;
 131 -       return 0;
 132 -}
 133 -
 134 -struct Qdisc_ops pfifo_fast_ops __read_mostly = {
 135 -       .id             =       "pfifo_fast",
 136 -       .priv_size      =       sizeof(struct pfifo_fast_priv),
 137 -       .enqueue        =       pfifo_fast_enqueue,
 138 -       .dequeue        =       pfifo_fast_dequeue,
 139 -       .peek           =       pfifo_fast_peek,
 140 -       .init           =       pfifo_fast_init,
 141 -       .reset          =       pfifo_fast_reset,
 142 -       .dump           =       pfifo_fast_dump,
 143 -       .owner          =       THIS_MODULE,
 144 -};
 145 -EXPORT_SYMBOL(pfifo_fast_ops);
 146 -
 147  static struct lock_class_key qdisc_tx_busylock;
 148  static struct lock_class_key qdisc_running_key;
 149