net_sched: increment drop counters in qdisc_tree_decrease_qlen()

qdisc_tree_decrease_qlen() is called when some packets are dropped
on a qdisc, and we want to notify parents of qlen changes.

We also can increment parents qdisc qstats drop counters.

This permits more accurate drop counters up to root qdisc.

For example a graft operation typically resets a qdisc
(drops all packets) and call qdisc_tree_decrease_qlen()

Note that callers are responsible for their drop counters.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Eric Dumazet 2013-10-07 08:32:32 -07:00 committed by David S. Miller
parent 4996b9098d
commit 2c8c8e6f9d

View File

@ -737,9 +737,11 @@ void qdisc_tree_decrease_qlen(struct Qdisc *sch, unsigned int n)
const struct Qdisc_class_ops *cops;
unsigned long cl;
u32 parentid;
int drops;
if (n == 0)
return;
drops = max_t(int, n, 0);
while ((parentid = sch->parent)) {
if (TC_H_MAJ(parentid) == TC_H_MAJ(TC_H_INGRESS))
return;
@ -756,6 +758,7 @@ void qdisc_tree_decrease_qlen(struct Qdisc *sch, unsigned int n)
cops->put(sch, cl);
}
sch->q.qlen -= n;
sch->qstats.drops += drops;
}
}
EXPORT_SYMBOL(qdisc_tree_decrease_qlen);