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-rw-r--r--net/sched/sch_qfq.c66
1 files changed, 45 insertions, 21 deletions
diff --git a/net/sched/sch_qfq.c b/net/sched/sch_qfq.c
index e9a77f6..d51852b 100644
--- a/net/sched/sch_qfq.c
+++ b/net/sched/sch_qfq.c
@@ -298,6 +298,10 @@ static void qfq_update_agg(struct qfq_sched *q, struct qfq_aggregate *agg,
new_num_classes == q->max_agg_classes - 1) /* agg no more full */
hlist_add_head(&agg->nonfull_next, &q->nonfull_aggs);
+ /* The next assignment may let
+ * agg->initial_budget > agg->budgetmax
+ * hold, we will take it into account in charge_actual_service().
+ */
agg->budgetmax = new_num_classes * agg->lmax;
new_agg_weight = agg->class_weight * new_num_classes;
agg->inv_w = ONE_FP/new_agg_weight;
@@ -817,7 +821,7 @@ static void qfq_make_eligible(struct qfq_sched *q)
unsigned long old_vslot = q->oldV >> q->min_slot_shift;
if (vslot != old_vslot) {
- unsigned long mask = (1UL << fls(vslot ^ old_vslot)) - 1;
+ unsigned long mask = (1ULL << fls(vslot ^ old_vslot)) - 1;
qfq_move_groups(q, mask, IR, ER);
qfq_move_groups(q, mask, IB, EB);
}
@@ -988,12 +992,23 @@ static inline struct sk_buff *qfq_peek_skb(struct qfq_aggregate *agg,
/* Update F according to the actual service received by the aggregate. */
static inline void charge_actual_service(struct qfq_aggregate *agg)
{
- /* compute the service received by the aggregate */
- u32 service_received = agg->initial_budget - agg->budget;
+ /* Compute the service received by the aggregate, taking into
+ * account that, after decreasing the number of classes in
+ * agg, it may happen that
+ * agg->initial_budget - agg->budget > agg->bugdetmax
+ */
+ u32 service_received = min(agg->budgetmax,
+ agg->initial_budget - agg->budget);
agg->F = agg->S + (u64)service_received * agg->inv_w;
}
+static inline void qfq_update_agg_ts(struct qfq_sched *q,
+ struct qfq_aggregate *agg,
+ enum update_reason reason);
+
+static void qfq_schedule_agg(struct qfq_sched *q, struct qfq_aggregate *agg);
+
static struct sk_buff *qfq_dequeue(struct Qdisc *sch)
{
struct qfq_sched *q = qdisc_priv(sch);
@@ -1021,7 +1036,7 @@ static struct sk_buff *qfq_dequeue(struct Qdisc *sch)
in_serv_agg->initial_budget = in_serv_agg->budget =
in_serv_agg->budgetmax;
- if (!list_empty(&in_serv_agg->active))
+ if (!list_empty(&in_serv_agg->active)) {
/*
* Still active: reschedule for
* service. Possible optimization: if no other
@@ -1032,8 +1047,9 @@ static struct sk_buff *qfq_dequeue(struct Qdisc *sch)
* handle it, we would need to maintain an
* extra num_active_aggs field.
*/
- qfq_activate_agg(q, in_serv_agg, requeue);
- else if (sch->q.qlen == 0) { /* no aggregate to serve */
+ qfq_update_agg_ts(q, in_serv_agg, requeue);
+ qfq_schedule_agg(q, in_serv_agg);
+ } else if (sch->q.qlen == 0) { /* no aggregate to serve */
q->in_serv_agg = NULL;
return NULL;
}
@@ -1052,7 +1068,15 @@ static struct sk_buff *qfq_dequeue(struct Qdisc *sch)
qdisc_bstats_update(sch, skb);
agg_dequeue(in_serv_agg, cl, len);
- in_serv_agg->budget -= len;
+ /* If lmax is lowered, through qfq_change_class, for a class
+ * owning pending packets with larger size than the new value
+ * of lmax, then the following condition may hold.
+ */
+ if (unlikely(in_serv_agg->budget < len))
+ in_serv_agg->budget = 0;
+ else
+ in_serv_agg->budget -= len;
+
q->V += (u64)len * IWSUM;
pr_debug("qfq dequeue: len %u F %lld now %lld\n",
len, (unsigned long long) in_serv_agg->F,
@@ -1217,17 +1241,11 @@ static int qfq_enqueue(struct sk_buff *skb, struct Qdisc *sch)
cl->deficit = agg->lmax;
list_add_tail(&cl->alist, &agg->active);
- if (list_first_entry(&agg->active, struct qfq_class, alist) != cl)
- return err; /* aggregate was not empty, nothing else to do */
+ if (list_first_entry(&agg->active, struct qfq_class, alist) != cl ||
+ q->in_serv_agg == agg)
+ return err; /* non-empty or in service, nothing else to do */
- /* recharge budget */
- agg->initial_budget = agg->budget = agg->budgetmax;
-
- qfq_update_agg_ts(q, agg, enqueue);
- if (q->in_serv_agg == NULL)
- q->in_serv_agg = agg;
- else if (agg != q->in_serv_agg)
- qfq_schedule_agg(q, agg);
+ qfq_activate_agg(q, agg, enqueue);
return err;
}
@@ -1261,7 +1279,8 @@ static void qfq_schedule_agg(struct qfq_sched *q, struct qfq_aggregate *agg)
/* group was surely ineligible, remove */
__clear_bit(grp->index, &q->bitmaps[IR]);
__clear_bit(grp->index, &q->bitmaps[IB]);
- } else if (!q->bitmaps[ER] && qfq_gt(roundedS, q->V))
+ } else if (!q->bitmaps[ER] && qfq_gt(roundedS, q->V) &&
+ q->in_serv_agg == NULL)
q->V = roundedS;
grp->S = roundedS;
@@ -1284,8 +1303,15 @@ skip_update:
static void qfq_activate_agg(struct qfq_sched *q, struct qfq_aggregate *agg,
enum update_reason reason)
{
+ agg->initial_budget = agg->budget = agg->budgetmax; /* recharge budg. */
+
qfq_update_agg_ts(q, agg, reason);
- qfq_schedule_agg(q, agg);
+ if (q->in_serv_agg == NULL) { /* no aggr. in service or scheduled */
+ q->in_serv_agg = agg; /* start serving this aggregate */
+ /* update V: to be in service, agg must be eligible */
+ q->oldV = q->V = agg->S;
+ } else if (agg != q->in_serv_agg)
+ qfq_schedule_agg(q, agg);
}
static void qfq_slot_remove(struct qfq_sched *q, struct qfq_group *grp,
@@ -1357,8 +1383,6 @@ static void qfq_deactivate_agg(struct qfq_sched *q, struct qfq_aggregate *agg)
__set_bit(grp->index, &q->bitmaps[s]);
}
}
-
- qfq_update_eligible(q);
}
static void qfq_qlen_notify(struct Qdisc *sch, unsigned long arg)
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