target/linux/generic/patches-4.4/030-net_sched-introduce-qdisc_replace-helper.patch

   1 From: WANG Cong <xiyou.wangcong@gmail.com>
   2 Date: Thu, 25 Feb 2016 14:55:00 -0800
   3 Subject: [PATCH] net_sched: introduce qdisc_replace() helper
   4
   5 Remove nearly duplicated code and prepare for the following patch.
   6
   7 Cc: Jamal Hadi Salim <jhs@mojatatu.com>
   8 Acked-by: Jamal Hadi Salim <jhs@mojatatu.com>
   9 Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
  10 Signed-off-by: David S. Miller <davem@davemloft.net>
  11 ---
  12
  13 --- a/include/net/sch_generic.h
  14 +++ b/include/net/sch_generic.h
  15 @@ -698,6 +698,23 @@ static inline void qdisc_reset_queue(str
  16         sch->qstats.backlog = 0;
  17  }
  18
  19 +static inline struct Qdisc *qdisc_replace(struct Qdisc *sch, struct Qdisc *new,
  20 +                                         struct Qdisc **pold)
  21 +{
  22 +       struct Qdisc *old;
  23 +
  24 +       sch_tree_lock(sch);
  25 +       old = *pold;
  26 +       *pold = new;
  27 +       if (old != NULL) {
  28 +               qdisc_tree_decrease_qlen(old, old->q.qlen);
  29 +               qdisc_reset(old);
  30 +       }
  31 +       sch_tree_unlock(sch);
  32 +
  33 +       return old;
  34 +}
  35 +
  36  static inline unsigned int __qdisc_queue_drop(struct Qdisc *sch,
  37                                               struct sk_buff_head *list)
  38  {
  39 --- a/net/sched/sch_cbq.c
  40 +++ b/net/sched/sch_cbq.c
  41 @@ -1624,13 +1624,8 @@ static int cbq_graft(struct Qdisc *sch,
  42                         new->reshape_fail = cbq_reshape_fail;
  43  #endif
  44         }
  45 -       sch_tree_lock(sch);
  46 -       *old = cl->q;
  47 -       cl->q = new;
  48 -       qdisc_tree_decrease_qlen(*old, (*old)->q.qlen);
  49 -       qdisc_reset(*old);
  50 -       sch_tree_unlock(sch);
  51
  52 +       *old = qdisc_replace(sch, new, &cl->q);
  53         return 0;
  54  }
  55
  56 --- a/net/sched/sch_drr.c
  57 +++ b/net/sched/sch_drr.c
  58 @@ -226,11 +226,7 @@ static int drr_graft_class(struct Qdisc
  59                         new = &noop_qdisc;
  60         }
  61
  62 -       sch_tree_lock(sch);
  63 -       drr_purge_queue(cl);
  64 -       *old = cl->qdisc;
  65 -       cl->qdisc = new;
  66 -       sch_tree_unlock(sch);
  67 +       *old = qdisc_replace(sch, new, &cl->qdisc);
  68         return 0;
  69  }
  70
  71 --- a/net/sched/sch_dsmark.c
  72 +++ b/net/sched/sch_dsmark.c
  73 @@ -73,13 +73,7 @@ static int dsmark_graft(struct Qdisc *sc
  74                         new = &noop_qdisc;
  75         }
  76
  77 -       sch_tree_lock(sch);
  78 -       *old = p->q;
  79 -       p->q = new;
  80 -       qdisc_tree_decrease_qlen(*old, (*old)->q.qlen);
  81 -       qdisc_reset(*old);
  82 -       sch_tree_unlock(sch);
  83 -
  84 +       *old = qdisc_replace(sch, new, &p->q);
  85         return 0;
  86  }
  87
  88 --- a/net/sched/sch_hfsc.c
  89 +++ b/net/sched/sch_hfsc.c
  90 @@ -1215,11 +1215,7 @@ hfsc_graft_class(struct Qdisc *sch, unsi
  91                         new = &noop_qdisc;
  92         }
  93
  94 -       sch_tree_lock(sch);
  95 -       hfsc_purge_queue(sch, cl);
  96 -       *old = cl->qdisc;
  97 -       cl->qdisc = new;
  98 -       sch_tree_unlock(sch);
  99 +       *old = qdisc_replace(sch, new, &cl->qdisc);
 100         return 0;
 101  }
 102
 103 --- a/net/sched/sch_htb.c
 104 +++ b/net/sched/sch_htb.c
 105 @@ -1163,14 +1163,7 @@ static int htb_graft(struct Qdisc *sch,
 106                                      cl->common.classid)) == NULL)
 107                 return -ENOBUFS;
 108
 109 -       sch_tree_lock(sch);
 110 -       *old = cl->un.leaf.q;
 111 -       cl->un.leaf.q = new;
 112 -       if (*old != NULL) {
 113 -               qdisc_tree_decrease_qlen(*old, (*old)->q.qlen);
 114 -               qdisc_reset(*old);
 115 -       }
 116 -       sch_tree_unlock(sch);
 117 +       *old = qdisc_replace(sch, new, &cl->un.leaf.q);
 118         return 0;
 119  }
 120
 121 --- a/net/sched/sch_multiq.c
 122 +++ b/net/sched/sch_multiq.c
 123 @@ -303,13 +303,7 @@ static int multiq_graft(struct Qdisc *sc
 124         if (new == NULL)
 125                 new = &noop_qdisc;
 126
 127 -       sch_tree_lock(sch);
 128 -       *old = q->queues[band];
 129 -       q->queues[band] = new;
 130 -       qdisc_tree_decrease_qlen(*old, (*old)->q.qlen);
 131 -       qdisc_reset(*old);
 132 -       sch_tree_unlock(sch);
 133 -
 134 +       *old = qdisc_replace(sch, new, &q->queues[band]);
 135         return 0;
 136  }
 137
 138 --- a/net/sched/sch_netem.c
 139 +++ b/net/sched/sch_netem.c
 140 @@ -1037,15 +1037,7 @@ static int netem_graft(struct Qdisc *sch
 141  {
 142         struct netem_sched_data *q = qdisc_priv(sch);
 143
 144 -       sch_tree_lock(sch);
 145 -       *old = q->qdisc;
 146 -       q->qdisc = new;
 147 -       if (*old) {
 148 -               qdisc_tree_decrease_qlen(*old, (*old)->q.qlen);
 149 -               qdisc_reset(*old);
 150 -       }
 151 -       sch_tree_unlock(sch);
 152 -
 153 +       *old = qdisc_replace(sch, new, &q->qdisc);
 154         return 0;
 155  }
 156
 157 --- a/net/sched/sch_prio.c
 158 +++ b/net/sched/sch_prio.c
 159 @@ -268,13 +268,7 @@ static int prio_graft(struct Qdisc *sch,
 160         if (new == NULL)
 161                 new = &noop_qdisc;
 162
 163 -       sch_tree_lock(sch);
 164 -       *old = q->queues[band];
 165 -       q->queues[band] = new;
 166 -       qdisc_tree_decrease_qlen(*old, (*old)->q.qlen);
 167 -       qdisc_reset(*old);
 168 -       sch_tree_unlock(sch);
 169 -
 170 +       *old = qdisc_replace(sch, new, &q->queues[band]);
 171         return 0;
 172  }
 173
 174 --- a/net/sched/sch_qfq.c
 175 +++ b/net/sched/sch_qfq.c
 176 @@ -617,11 +617,7 @@ static int qfq_graft_class(struct Qdisc
 177                         new = &noop_qdisc;
 178         }
 179
 180 -       sch_tree_lock(sch);
 181 -       qfq_purge_queue(cl);
 182 -       *old = cl->qdisc;
 183 -       cl->qdisc = new;
 184 -       sch_tree_unlock(sch);
 185 +       *old = qdisc_replace(sch, new, &cl->qdisc);
 186         return 0;
 187  }
 188
 189 --- a/net/sched/sch_red.c
 190 +++ b/net/sched/sch_red.c
 191 @@ -313,12 +313,7 @@ static int red_graft(struct Qdisc *sch,
 192         if (new == NULL)
 193                 new = &noop_qdisc;
 194
 195 -       sch_tree_lock(sch);
 196 -       *old = q->qdisc;
 197 -       q->qdisc = new;
 198 -       qdisc_tree_decrease_qlen(*old, (*old)->q.qlen);
 199 -       qdisc_reset(*old);
 200 -       sch_tree_unlock(sch);
 201 +       *old = qdisc_replace(sch, new, &q->qdisc);
 202         return 0;
 203  }
 204
 205 --- a/net/sched/sch_sfb.c
 206 +++ b/net/sched/sch_sfb.c
 207 @@ -606,12 +606,7 @@ static int sfb_graft(struct Qdisc *sch,
 208         if (new == NULL)
 209                 new = &noop_qdisc;
 210
 211 -       sch_tree_lock(sch);
 212 -       *old = q->qdisc;
 213 -       q->qdisc = new;
 214 -       qdisc_tree_decrease_qlen(*old, (*old)->q.qlen);
 215 -       qdisc_reset(*old);
 216 -       sch_tree_unlock(sch);
 217 +       *old = qdisc_replace(sch, new, &q->qdisc);
 218         return 0;
 219  }
 220
 221 --- a/net/sched/sch_tbf.c
 222 +++ b/net/sched/sch_tbf.c
 223 @@ -502,13 +502,7 @@ static int tbf_graft(struct Qdisc *sch,
 224         if (new == NULL)
 225                 new = &noop_qdisc;
 226
 227 -       sch_tree_lock(sch);
 228 -       *old = q->qdisc;
 229 -       q->qdisc = new;
 230 -       qdisc_tree_decrease_qlen(*old, (*old)->q.qlen);
 231 -       qdisc_reset(*old);
 232 -       sch_tree_unlock(sch);
 233 -
 234 +       *old = qdisc_replace(sch, new, &q->qdisc);
 235         return 0;
 236  }
 237