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-rw-r--r--include/net/sch_generic.h3
-rw-r--r--net/sched/sch_api.c27
-rw-r--r--net/sched/sch_generic.c2
-rw-r--r--net/sched/sch_mq.c4
-rw-r--r--net/sched/sch_mqprio.c4
5 files changed, 26 insertions, 14 deletions
diff --git a/include/net/sch_generic.h b/include/net/sch_generic.h
index 4c79ce8c1f92..b2a8e6338576 100644
--- a/include/net/sch_generic.h
+++ b/include/net/sch_generic.h
@@ -61,6 +61,9 @@ struct Qdisc {
*/
#define TCQ_F_WARN_NONWC (1 << 16)
#define TCQ_F_CPUSTATS 0x20 /* run using percpu statistics */
+#define TCQ_F_NOPARENT 0x40 /* root of its hierarchy :
+ * qdisc_tree_decrease_qlen() should stop.
+ */
u32 limit;
const struct Qdisc_ops *ops;
struct qdisc_size_table __rcu *stab;
diff --git a/net/sched/sch_api.c b/net/sched/sch_api.c
index f43c8f33f09e..7ec667dd4ce1 100644
--- a/net/sched/sch_api.c
+++ b/net/sched/sch_api.c
@@ -253,7 +253,8 @@ int qdisc_set_default(const char *name)
}
/* We know handle. Find qdisc among all qdisc's attached to device
- (root qdisc, all its children, children of children etc.)
+ * (root qdisc, all its children, children of children etc.)
+ * Note: caller either uses rtnl or rcu_read_lock()
*/
static struct Qdisc *qdisc_match_from_root(struct Qdisc *root, u32 handle)
@@ -264,7 +265,7 @@ static struct Qdisc *qdisc_match_from_root(struct Qdisc *root, u32 handle)
root->handle == handle)
return root;
- list_for_each_entry(q, &root->list, list) {
+ list_for_each_entry_rcu(q, &root->list, list) {
if (q->handle == handle)
return q;
}
@@ -277,15 +278,18 @@ void qdisc_list_add(struct Qdisc *q)
struct Qdisc *root = qdisc_dev(q)->qdisc;
WARN_ON_ONCE(root == &noop_qdisc);
- list_add_tail(&q->list, &root->list);
+ ASSERT_RTNL();
+ list_add_tail_rcu(&q->list, &root->list);
}
}
EXPORT_SYMBOL(qdisc_list_add);
void qdisc_list_del(struct Qdisc *q)
{
- if ((q->parent != TC_H_ROOT) && !(q->flags & TCQ_F_INGRESS))
- list_del(&q->list);
+ if ((q->parent != TC_H_ROOT) && !(q->flags & TCQ_F_INGRESS)) {
+ ASSERT_RTNL();
+ list_del_rcu(&q->list);
+ }
}
EXPORT_SYMBOL(qdisc_list_del);
@@ -750,14 +754,18 @@ void qdisc_tree_decrease_qlen(struct Qdisc *sch, unsigned int n)
if (n == 0)
return;
drops = max_t(int, n, 0);
+ rcu_read_lock();
while ((parentid = sch->parent)) {
if (TC_H_MAJ(parentid) == TC_H_MAJ(TC_H_INGRESS))
- return;
+ break;
+ if (sch->flags & TCQ_F_NOPARENT)
+ break;
+ /* TODO: perform the search on a per txq basis */
sch = qdisc_lookup(qdisc_dev(sch), TC_H_MAJ(parentid));
if (sch == NULL) {
- WARN_ON(parentid != TC_H_ROOT);
- return;
+ WARN_ON_ONCE(parentid != TC_H_ROOT);
+ break;
}
cops = sch->ops->cl_ops;
if (cops->qlen_notify) {
@@ -768,6 +776,7 @@ void qdisc_tree_decrease_qlen(struct Qdisc *sch, unsigned int n)
sch->q.qlen -= n;
__qdisc_qstats_drop(sch, drops);
}
+ rcu_read_unlock();
}
EXPORT_SYMBOL(qdisc_tree_decrease_qlen);
@@ -941,7 +950,7 @@ qdisc_create(struct net_device *dev, struct netdev_queue *dev_queue,
}
lockdep_set_class(qdisc_lock(sch), &qdisc_tx_lock);
if (!netif_is_multiqueue(dev))
- sch->flags |= TCQ_F_ONETXQUEUE;
+ sch->flags |= TCQ_F_ONETXQUEUE | TCQ_F_NOPARENT;
}
sch->handle = handle;
diff --git a/net/sched/sch_generic.c b/net/sched/sch_generic.c
index cb5d4ad32946..e82a1ad80aa5 100644
--- a/net/sched/sch_generic.c
+++ b/net/sched/sch_generic.c
@@ -737,7 +737,7 @@ static void attach_one_default_qdisc(struct net_device *dev,
return;
}
if (!netif_is_multiqueue(dev))
- qdisc->flags |= TCQ_F_ONETXQUEUE;
+ qdisc->flags |= TCQ_F_ONETXQUEUE | TCQ_F_NOPARENT;
dev_queue->qdisc_sleeping = qdisc;
}
diff --git a/net/sched/sch_mq.c b/net/sched/sch_mq.c
index f3cbaecd283a..3e82f047caaf 100644
--- a/net/sched/sch_mq.c
+++ b/net/sched/sch_mq.c
@@ -63,7 +63,7 @@ static int mq_init(struct Qdisc *sch, struct nlattr *opt)
if (qdisc == NULL)
goto err;
priv->qdiscs[ntx] = qdisc;
- qdisc->flags |= TCQ_F_ONETXQUEUE;
+ qdisc->flags |= TCQ_F_ONETXQUEUE | TCQ_F_NOPARENT;
}
sch->flags |= TCQ_F_MQROOT;
@@ -156,7 +156,7 @@ static int mq_graft(struct Qdisc *sch, unsigned long cl, struct Qdisc *new,
*old = dev_graft_qdisc(dev_queue, new);
if (new)
- new->flags |= TCQ_F_ONETXQUEUE;
+ new->flags |= TCQ_F_ONETXQUEUE | TCQ_F_NOPARENT;
if (dev->flags & IFF_UP)
dev_activate(dev);
return 0;
diff --git a/net/sched/sch_mqprio.c b/net/sched/sch_mqprio.c
index 3811a745452c..ad70ecf57ce7 100644
--- a/net/sched/sch_mqprio.c
+++ b/net/sched/sch_mqprio.c
@@ -132,7 +132,7 @@ static int mqprio_init(struct Qdisc *sch, struct nlattr *opt)
goto err;
}
priv->qdiscs[i] = qdisc;
- qdisc->flags |= TCQ_F_ONETXQUEUE;
+ qdisc->flags |= TCQ_F_ONETXQUEUE | TCQ_F_NOPARENT;
}
/* If the mqprio options indicate that hardware should own
@@ -209,7 +209,7 @@ static int mqprio_graft(struct Qdisc *sch, unsigned long cl, struct Qdisc *new,
*old = dev_graft_qdisc(dev_queue, new);
if (new)
- new->flags |= TCQ_F_ONETXQUEUE;
+ new->flags |= TCQ_F_ONETXQUEUE | TCQ_F_NOPARENT;
if (dev->flags & IFF_UP)
dev_activate(dev);