summaryrefslogtreecommitdiffstats
path: root/net/sched/sch_qfq.c
diff options
context:
space:
mode:
Diffstat (limited to 'net/sched/sch_qfq.c')
-rw-r--r--net/sched/sch_qfq.c95
1 files changed, 69 insertions, 26 deletions
diff --git a/net/sched/sch_qfq.c b/net/sched/sch_qfq.c
index 9af01f3df18c..e4723d31fdd5 100644
--- a/net/sched/sch_qfq.c
+++ b/net/sched/sch_qfq.c
@@ -203,6 +203,34 @@ out:
return index;
}
+/* Length of the next packet (0 if the queue is empty). */
+static unsigned int qdisc_peek_len(struct Qdisc *sch)
+{
+ struct sk_buff *skb;
+
+ skb = sch->ops->peek(sch);
+ return skb ? qdisc_pkt_len(skb) : 0;
+}
+
+static void qfq_deactivate_class(struct qfq_sched *, struct qfq_class *);
+static void qfq_activate_class(struct qfq_sched *q, struct qfq_class *cl,
+ unsigned int len);
+
+static void qfq_update_class_params(struct qfq_sched *q, struct qfq_class *cl,
+ u32 lmax, u32 inv_w, int delta_w)
+{
+ int i;
+
+ /* update qfq-specific data */
+ cl->lmax = lmax;
+ cl->inv_w = inv_w;
+ i = qfq_calc_index(cl->inv_w, cl->lmax);
+
+ cl->grp = &q->groups[i];
+
+ q->wsum += delta_w;
+}
+
static int qfq_change_class(struct Qdisc *sch, u32 classid, u32 parentid,
struct nlattr **tca, unsigned long *arg)
{
@@ -250,6 +278,8 @@ static int qfq_change_class(struct Qdisc *sch, u32 classid, u32 parentid,
lmax = 1UL << QFQ_MTU_SHIFT;
if (cl != NULL) {
+ bool need_reactivation = false;
+
if (tca[TCA_RATE]) {
err = gen_replace_estimator(&cl->bstats, &cl->rate_est,
qdisc_root_sleeping_lock(sch),
@@ -258,12 +288,29 @@ static int qfq_change_class(struct Qdisc *sch, u32 classid, u32 parentid,
return err;
}
- if (inv_w != cl->inv_w) {
- sch_tree_lock(sch);
- q->wsum += delta_w;
- cl->inv_w = inv_w;
- sch_tree_unlock(sch);
+ if (lmax == cl->lmax && inv_w == cl->inv_w)
+ return 0; /* nothing to update */
+
+ i = qfq_calc_index(inv_w, lmax);
+ sch_tree_lock(sch);
+ if (&q->groups[i] != cl->grp && cl->qdisc->q.qlen > 0) {
+ /*
+ * shift cl->F back, to not charge the
+ * class for the not-yet-served head
+ * packet
+ */
+ cl->F = cl->S;
+ /* remove class from its slot in the old group */
+ qfq_deactivate_class(q, cl);
+ need_reactivation = true;
}
+
+ qfq_update_class_params(q, cl, lmax, inv_w, delta_w);
+
+ if (need_reactivation) /* activate in new group */
+ qfq_activate_class(q, cl, qdisc_peek_len(cl->qdisc));
+ sch_tree_unlock(sch);
+
return 0;
}
@@ -273,11 +320,8 @@ static int qfq_change_class(struct Qdisc *sch, u32 classid, u32 parentid,
cl->refcnt = 1;
cl->common.classid = classid;
- cl->lmax = lmax;
- cl->inv_w = inv_w;
- i = qfq_calc_index(cl->inv_w, cl->lmax);
- cl->grp = &q->groups[i];
+ qfq_update_class_params(q, cl, lmax, inv_w, delta_w);
cl->qdisc = qdisc_create_dflt(sch->dev_queue,
&pfifo_qdisc_ops, classid);
@@ -294,7 +338,6 @@ static int qfq_change_class(struct Qdisc *sch, u32 classid, u32 parentid,
return err;
}
}
- q->wsum += weight;
sch_tree_lock(sch);
qdisc_class_hash_insert(&q->clhash, &cl->common);
@@ -711,15 +754,6 @@ static void qfq_update_eligible(struct qfq_sched *q, u64 old_V)
}
}
-/* What is length of next packet in queue (0 if queue is empty) */
-static unsigned int qdisc_peek_len(struct Qdisc *sch)
-{
- struct sk_buff *skb;
-
- skb = sch->ops->peek(sch);
- return skb ? qdisc_pkt_len(skb) : 0;
-}
-
/*
* Updates the class, returns true if also the group needs to be updated.
*/
@@ -843,11 +877,8 @@ static void qfq_update_start(struct qfq_sched *q, struct qfq_class *cl)
static int qfq_enqueue(struct sk_buff *skb, struct Qdisc *sch)
{
struct qfq_sched *q = qdisc_priv(sch);
- struct qfq_group *grp;
struct qfq_class *cl;
int err;
- u64 roundedS;
- int s;
cl = qfq_classify(skb, sch, &err);
if (cl == NULL) {
@@ -876,11 +907,25 @@ static int qfq_enqueue(struct sk_buff *skb, struct Qdisc *sch)
return err;
/* If reach this point, queue q was idle */
- grp = cl->grp;
+ qfq_activate_class(q, cl, qdisc_pkt_len(skb));
+
+ return err;
+}
+
+/*
+ * Handle class switch from idle to backlogged.
+ */
+static void qfq_activate_class(struct qfq_sched *q, struct qfq_class *cl,
+ unsigned int pkt_len)
+{
+ struct qfq_group *grp = cl->grp;
+ u64 roundedS;
+ int s;
+
qfq_update_start(q, cl);
/* compute new finish time and rounded start. */
- cl->F = cl->S + (u64)qdisc_pkt_len(skb) * cl->inv_w;
+ cl->F = cl->S + (u64)pkt_len * cl->inv_w;
roundedS = qfq_round_down(cl->S, grp->slot_shift);
/*
@@ -917,8 +962,6 @@ static int qfq_enqueue(struct sk_buff *skb, struct Qdisc *sch)
skip_update:
qfq_slot_insert(grp, cl, roundedS);
-
- return err;
}