| Message ID | 1465602099-15808-4-git-send-email-edumazet@google.com |
|---|---|
| State | Accepted, archived |
| Delegated to: | David Miller |
| Headers | show |
On Fri, 2016-06-10 at 16:41 -0700, Eric Dumazet wrote: > Looks like it is only there as some optimization attempt. > > Since __QDISC_STATE_THROTTLED set/unset is way too expensive, > and netem is the last user, just remove this check. > > Signed-off-by: Eric Dumazet <edumazet@google.com> > --- > net/sched/sch_netem.c | 3 --- > 1 file changed, 3 deletions(-) > > diff --git a/net/sched/sch_netem.c b/net/sched/sch_netem.c > index 9ca7947ab643..2dbe732ca135 100644 > --- a/net/sched/sch_netem.c > +++ b/net/sched/sch_netem.c > @@ -582,9 +582,6 @@ static struct sk_buff *netem_dequeue(struct Qdisc *sch) > struct sk_buff *skb; > struct rb_node *p; > > - if (qdisc_is_throttled(sch)) > - return NULL; > - > tfifo_dequeue: > skb = __skb_dequeue(&sch->q); > if (skb) { Note that this commit (42117927cab5a13192ecc227bea19da5059ffc6c "net_sched: netem: remove qdisc_is_throttled() use") is a stable candidate, as it incidentally removes one long standing bug. Namely, we were not calling qdisc_unthrottled() from netem enqueue(), so we would be forced to wait a timer activation to be able to drain the queue(s). This matters with either a jitter, or a "tc qdisc change ... delay <new delay>"
diff --git a/net/sched/sch_netem.c b/net/sched/sch_netem.c index 9ca7947ab643..2dbe732ca135 100644 --- a/net/sched/sch_netem.c +++ b/net/sched/sch_netem.c @@ -582,9 +582,6 @@ static struct sk_buff *netem_dequeue(struct Qdisc *sch) struct sk_buff *skb; struct rb_node *p; - if (qdisc_is_throttled(sch)) - return NULL; - tfifo_dequeue: skb = __skb_dequeue(&sch->q); if (skb) {
Looks like it is only there as some optimization attempt. Since __QDISC_STATE_THROTTLED set/unset is way too expensive, and netem is the last user, just remove this check. Signed-off-by: Eric Dumazet <edumazet@google.com> --- net/sched/sch_netem.c | 3 --- 1 file changed, 3 deletions(-)