fq_codel: should use qdisc backlog as threshold
codel_should_drop() logic allows a packet being not dropped if queue
size is under max packet size.
In fq_codel, we have two possible backlogs : The qdisc global one, and
the flow local one.
The meaningful one for codel_should_drop() should be the global backlog,
not the per flow one, so that thin flows can have a non zero drop/mark
probability.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Dave Taht <dave.taht@bufferbloat.net>
Cc: Kathleen Nichols <nichols@pollere.com>
Cc: Van Jacobson <van@pollere.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/sched/sch_fq_codel.c b/net/sched/sch_fq_codel.c
index 337ff20..9fc1c62 100644
--- a/net/sched/sch_fq_codel.c
+++ b/net/sched/sch_fq_codel.c
@@ -217,13 +217,14 @@
*/
static struct sk_buff *dequeue(struct codel_vars *vars, struct Qdisc *sch)
{
+ struct fq_codel_sched_data *q = qdisc_priv(sch);
struct fq_codel_flow *flow;
struct sk_buff *skb = NULL;
flow = container_of(vars, struct fq_codel_flow, cvars);
if (flow->head) {
skb = dequeue_head(flow);
- sch->qstats.backlog -= qdisc_pkt_len(skb);
+ q->backlogs[flow - q->flows] -= qdisc_pkt_len(skb);
sch->q.qlen--;
}
return skb;
@@ -256,7 +257,7 @@
prev_ecn_mark = q->cstats.ecn_mark;
skb = codel_dequeue(sch, &q->cparams, &flow->cvars, &q->cstats,
- dequeue, &q->backlogs[flow - q->flows]);
+ dequeue);
flow->dropped += q->cstats.drop_count - prev_drop_count;
flow->dropped += q->cstats.ecn_mark - prev_ecn_mark;