From cbdf451164785c9cf5acd5d2983c1e7c778df4c1 Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Sun, 12 Jun 2016 16:21:47 -0700 Subject: [PATCH] net_sched: prio: properly report out of memory errors At Qdisc creation or change time, prio_tune() creates missing pfifo qdiscs but does not return an error code if one qdisc could not be allocated. Leaving a qdisc in non operational state without telling user anything about this problem is not good. Also, testing if we replace something different than noop_qdisc a second time makes no sense so I removed useless code. Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller --- net/sched/sch_prio.c | 28 ++++++++++------------------ 1 file changed, 10 insertions(+), 18 deletions(-) diff --git a/net/sched/sch_prio.c b/net/sched/sch_prio.c index 4b0a82191bc4..071718bccdab 100644 --- a/net/sched/sch_prio.c +++ b/net/sched/sch_prio.c @@ -202,26 +202,18 @@ static int prio_tune(struct Qdisc *sch, struct nlattr *opt) sch_tree_unlock(sch); for (i = 0; i < q->bands; i++) { - if (q->queues[i] == &noop_qdisc) { - struct Qdisc *child, *old; + struct Qdisc *child; - child = qdisc_create_dflt(sch->dev_queue, - &pfifo_qdisc_ops, - TC_H_MAKE(sch->handle, i + 1)); - if (child) { - sch_tree_lock(sch); - old = q->queues[i]; - q->queues[i] = child; + if (q->queues[i] != &noop_qdisc) + continue; - if (old != &noop_qdisc) { - qdisc_tree_reduce_backlog(old, - old->q.qlen, - old->qstats.backlog); - qdisc_destroy(old); - } - sch_tree_unlock(sch); - } - } + child = qdisc_create_dflt(sch->dev_queue, &pfifo_qdisc_ops, + TC_H_MAKE(sch->handle, i + 1)); + if (!child) + return -ENOMEM; + sch_tree_lock(sch); + q->queues[i] = child; + sch_tree_unlock(sch); } return 0; }