[PATCH 4.5 026/101] net_sched: introduce qdisc_replace() helper

Greg Kroah-Hartman
2016-05-17T01:24:47Z

From: WANG Cong <xiyou.wangcong@gmail.com>

[ Upstream commit 86a7996cc8a078793670d82ed97d5a99bb4e8496 ]

Remove nearly duplicated code and prepare for the following patch.

Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Acked-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
include/net/sch_generic.h | 17 +++++++++++++++++
net/sched/sch_cbq.c | 7 +------
net/sched/sch_drr.c | 6 +-----
net/sched/sch_dsmark.c | 8 +-------
net/sched/sch_hfsc.c | 6 +-----
net/sched/sch_htb.c | 9 +--------
net/sched/sch_multiq.c | 8 +-------
net/sched/sch_netem.c | 10 +---------
net/sched/sch_prio.c | 8 +-------
net/sched/sch_qfq.c | 6 +-----
net/sched/sch_red.c | 7 +------
net/sched/sch_sfb.c | 7 +------
net/sched/sch_tbf.c | 8 +-------
13 files changed, 29 insertions(+), 78 deletions(-)

--- a/include/net/sch_generic.h
+++ b/include/net/sch_generic.h
@@ -707,6 +707,23 @@ static inline void qdisc_reset_queue(str
sch->qstats.backlog = 0;
}

+static inline struct Qdisc *qdisc_replace(struct Qdisc *sch, struct Qdisc *new,
+ struct Qdisc **pold)
+{
+ struct Qdisc *old;
+
+ sch_tree_lock(sch);
+ old = *pold;
+ *pold = new;
+ if (old != NULL) {
+ qdisc_tree_decrease_qlen(old, old->q.qlen);
+ qdisc_reset(old);
+ }
+ sch_tree_unlock(sch);
+
+ return old;
+}
+
static inline unsigned int __qdisc_queue_drop(struct Qdisc *sch,
struct sk_buff_head *list)
{
--- a/net/sched/sch_cbq.c
+++ b/net/sched/sch_cbq.c
@@ -1624,13 +1624,8 @@ static int cbq_graft(struct Qdisc *sch,
new->reshape_fail = cbq_reshape_fail;
#endif
}
- sch_tree_lock(sch);
- *old = cl->q;
- cl->q = new;
- qdisc_tree_decrease_qlen(*old, (*old)->q.qlen);
- qdisc_reset(*old);
- sch_tree_unlock(sch);

+ *old = qdisc_replace(sch, new, &cl->q);
return 0;
}

--- a/net/sched/sch_drr.c
+++ b/net/sched/sch_drr.c
@@ -226,11 +226,7 @@ static int drr_graft_class(struct Qdisc
new = &noop_qdisc;
}

- sch_tree_lock(sch);
- drr_purge_queue(cl);
- *old = cl->qdisc;
- cl->qdisc = new;
- sch_tree_unlock(sch);
+ *old = qdisc_replace(sch, new, &cl->qdisc);
return 0;
}

--- a/net/sched/sch_dsmark.c
+++ b/net/sched/sch_dsmark.c
@@ -73,13 +73,7 @@ static int dsmark_graft(struct Qdisc *sc
new = &noop_qdisc;
}

- sch_tree_lock(sch);
- *old = p->q;
- p->q = new;
- qdisc_tree_decrease_qlen(*old, (*old)->q.qlen);
- qdisc_reset(*old);
- sch_tree_unlock(sch);
-
+ *old = qdisc_replace(sch, new, &p->q);
return 0;
}

--- a/net/sched/sch_hfsc.c
+++ b/net/sched/sch_hfsc.c
@@ -1215,11 +1215,7 @@ hfsc_graft_class(struct Qdisc *sch, unsi
new = &noop_qdisc;
}

- sch_tree_lock(sch);
- hfsc_purge_queue(sch, cl);
- *old = cl->qdisc;
- cl->qdisc = new;
- sch_tree_unlock(sch);
+ *old = qdisc_replace(sch, new, &cl->qdisc);
return 0;
}

--- a/net/sched/sch_htb.c
+++ b/net/sched/sch_htb.c
@@ -1163,14 +1163,7 @@ static int htb_graft(struct Qdisc *sch,
cl->common.classid)) == NULL)
return -ENOBUFS;

- sch_tree_lock(sch);
- *old = cl->un.leaf.q;
- cl->un.leaf.q = new;
- if (*old != NULL) {
- qdisc_tree_decrease_qlen(*old, (*old)->q.qlen);
- qdisc_reset(*old);
- }
- sch_tree_unlock(sch);
+ *old = qdisc_replace(sch, new, &cl->un.leaf.q);
return 0;
}

--- a/net/sched/sch_multiq.c
+++ b/net/sched/sch_multiq.c
@@ -303,13 +303,7 @@ static int multiq_graft(struct Qdisc *sc
if (new == NULL)
new = &noop_qdisc;

- sch_tree_lock(sch);
- *old = q->queues[band];
- q->queues[band] = new;
- qdisc_tree_decrease_qlen(*old, (*old)->q.qlen);
- qdisc_reset(*old);
- sch_tree_unlock(sch);
-
+ *old = qdisc_replace(sch, new, &q->queues[band]);
return 0;
}

--- a/net/sched/sch_netem.c
+++ b/net/sched/sch_netem.c
@@ -1037,15 +1037,7 @@ static int netem_graft(struct Qdisc *sch
{
struct netem_sched_data *q = qdisc_priv(sch);

- sch_tree_lock(sch);
- *old = q->qdisc;
- q->qdisc = new;
- if (*old) {
- qdisc_tree_decrease_qlen(*old, (*old)->q.qlen);
- qdisc_reset(*old);
- }
- sch_tree_unlock(sch);
-
+ *old = qdisc_replace(sch, new, &q->qdisc);
return 0;
}

--- a/net/sched/sch_prio.c
+++ b/net/sched/sch_prio.c
@@ -268,13 +268,7 @@ static int prio_graft(struct Qdisc *sch,
if (new == NULL)
new = &noop_qdisc;

- sch_tree_lock(sch);
- *old = q->queues[band];
- q->queues[band] = new;
- qdisc_tree_decrease_qlen(*old, (*old)->q.qlen);
- qdisc_reset(*old);
- sch_tree_unlock(sch);
-
+ *old = qdisc_replace(sch, new, &q->queues[band]);
return 0;
}

--- a/net/sched/sch_qfq.c
+++ b/net/sched/sch_qfq.c
@@ -617,11 +617,7 @@ static int qfq_graft_class(struct Qdisc
new = &noop_qdisc;
}

- sch_tree_lock(sch);
- qfq_purge_queue(cl);
- *old = cl->qdisc;
- cl->qdisc = new;
- sch_tree_unlock(sch);
+ *old = qdisc_replace(sch, new, &cl->qdisc);
return 0;
}

--- a/net/sched/sch_red.c
+++ b/net/sched/sch_red.c
@@ -313,12 +313,7 @@ static int red_graft(struct Qdisc *sch,
if (new == NULL)
new = &noop_qdisc;

- sch_tree_lock(sch);
- *old = q->qdisc;
- q->qdisc = new;
- qdisc_tree_decrease_qlen(*old, (*old)->q.qlen);
- qdisc_reset(*old);
- sch_tree_unlock(sch);
+ *old = qdisc_replace(sch, new, &q->qdisc);
return 0;
}

--- a/net/sched/sch_sfb.c
+++ b/net/sched/sch_sfb.c
@@ -606,12 +606,7 @@ static int sfb_graft(struct Qdisc *sch,
if (new == NULL)
new = &noop_qdisc;

- sch_tree_lock(sch);
- *old = q->qdisc;
- q->qdisc = new;
- qdisc_tree_decrease_qlen(*old, (*old)->q.qlen);
- qdisc_reset(*old);
- sch_tree_unlock(sch);
+ *old = qdisc_replace(sch, new, &q->qdisc);
return 0;
}

--- a/net/sched/sch_tbf.c
+++ b/net/sched/sch_tbf.c
@@ -502,13 +502,7 @@ static int tbf_graft(struct Qdisc *sch,
if (new == NULL)
new = &noop_qdisc;

- sch_tree_lock(sch);
- *old = q->qdisc;
- q->qdisc = new;
- qdisc_tree_decrease_qlen(*old, (*old)->q.qlen);
- qdisc_reset(*old);
- sch_tree_unlock(sch);
-
+ *old = qdisc_replace(sch, new, &q->qdisc);
return 0;
}