pkt_sched: fq: fix non TCP flows pacing
Steinar reported FQ pacing was not working for UDP flows.
It looks like the initial sk->sk_pacing_rate value of 0 was
a wrong choice. We should init it to ~0U (unlimited)
Then, TCA_FQ_FLOW_DEFAULT_RATE should be removed because it makes
no real sense. The default rate is really unlimited, and we
need to avoid a zero divide.
Reported-by: Steinar H. Gunderson <sesse@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/core/sock.c b/net/core/sock.c
index 5b6beba..0b39e7a 100644
--- a/net/core/sock.c
+++ b/net/core/sock.c
@@ -2319,6 +2319,7 @@
sk->sk_ll_usec = sysctl_net_busy_read;
#endif
+ sk->sk_pacing_rate = ~0U;
/*
* Before updating sk_refcnt, we must commit prior changes to memory
* (Documentation/RCU/rculist_nulls.txt for details)
diff --git a/net/sched/sch_fq.c b/net/sched/sch_fq.c
index 48501a2..a9dfdda 100644
--- a/net/sched/sch_fq.c
+++ b/net/sched/sch_fq.c
@@ -472,20 +472,16 @@
if (f->credit > 0 || !q->rate_enable)
goto out;
- if (skb->sk && skb->sk->sk_state != TCP_TIME_WAIT) {
- rate = skb->sk->sk_pacing_rate ?: q->flow_default_rate;
+ rate = q->flow_max_rate;
+ if (skb->sk && skb->sk->sk_state != TCP_TIME_WAIT)
+ rate = min(skb->sk->sk_pacing_rate, rate);
- rate = min(rate, q->flow_max_rate);
- } else {
- rate = q->flow_max_rate;
- if (rate == ~0U)
- goto out;
- }
- if (rate) {
+ if (rate != ~0U) {
u32 plen = max(qdisc_pkt_len(skb), q->quantum);
u64 len = (u64)plen * NSEC_PER_SEC;
- do_div(len, rate);
+ if (likely(rate))
+ do_div(len, rate);
/* Since socket rate can change later,
* clamp the delay to 125 ms.
* TODO: maybe segment the too big skb, as in commit
@@ -735,12 +731,14 @@
if (opts == NULL)
goto nla_put_failure;
+ /* TCA_FQ_FLOW_DEFAULT_RATE is not used anymore,
+ * do not bother giving its value
+ */
if (nla_put_u32(skb, TCA_FQ_PLIMIT, sch->limit) ||
nla_put_u32(skb, TCA_FQ_FLOW_PLIMIT, q->flow_plimit) ||
nla_put_u32(skb, TCA_FQ_QUANTUM, q->quantum) ||
nla_put_u32(skb, TCA_FQ_INITIAL_QUANTUM, q->initial_quantum) ||
nla_put_u32(skb, TCA_FQ_RATE_ENABLE, q->rate_enable) ||
- nla_put_u32(skb, TCA_FQ_FLOW_DEFAULT_RATE, q->flow_default_rate) ||
nla_put_u32(skb, TCA_FQ_FLOW_MAX_RATE, q->flow_max_rate) ||
nla_put_u32(skb, TCA_FQ_BUCKETS_LOG, q->fq_trees_log))
goto nla_put_failure;