From 256d61b87b2c2ac6fc333c1654d1abea61979006 Mon Sep 17 00:00:00 2001 From: Patrick McHardy Date: Wed, 29 Nov 2006 17:37:05 -0800 Subject: [PATCH] [NET_SCHED]: Fix endless loops (part 4): HTB Convert HTB to use qdisc_tree_decrease_len() and add a callback for deactivating a class when its child queue becomes empty. Signed-off-by: Patrick McHardy Signed-off-by: David S. Miller --- net/sched/sch_htb.c | 24 +++++++++++++++++------- 1 file changed, 17 insertions(+), 7 deletions(-) diff --git a/net/sched/sch_htb.c b/net/sched/sch_htb.c index 3b36e9d60c2..215e68c2b61 100644 --- a/net/sched/sch_htb.c +++ b/net/sched/sch_htb.c @@ -1230,11 +1230,7 @@ static int htb_graft(struct Qdisc *sch, unsigned long arg, struct Qdisc *new, return -ENOBUFS; sch_tree_lock(sch); if ((*old = xchg(&cl->un.leaf.q, new)) != NULL) { - if (cl->prio_activity) - htb_deactivate(qdisc_priv(sch), cl); - - /* TODO: is it correct ? Why CBQ doesn't do it ? */ - sch->q.qlen -= (*old)->q.qlen; + qdisc_tree_decrease_qlen(*old, (*old)->q.qlen); qdisc_reset(*old); } sch_tree_unlock(sch); @@ -1249,6 +1245,14 @@ static struct Qdisc *htb_leaf(struct Qdisc *sch, unsigned long arg) return (cl && !cl->level) ? cl->un.leaf.q : NULL; } +static void htb_qlen_notify(struct Qdisc *sch, unsigned long arg) +{ + struct htb_class *cl = (struct htb_class *)arg; + + if (cl->un.leaf.q->q.qlen == 0) + htb_deactivate(qdisc_priv(sch), cl); +} + static unsigned long htb_get(struct Qdisc *sch, u32 classid) { struct htb_class *cl = htb_find(classid, sch); @@ -1323,6 +1327,7 @@ static int htb_delete(struct Qdisc *sch, unsigned long arg) { struct htb_sched *q = qdisc_priv(sch); struct htb_class *cl = (struct htb_class *)arg; + unsigned int qlen; // TODO: why don't allow to delete subtree ? references ? does // tc subsys quarantee us that in htb_destroy it holds no class @@ -1336,8 +1341,9 @@ static int htb_delete(struct Qdisc *sch, unsigned long arg) hlist_del_init(&cl->hlist); if (!cl->level) { - sch->q.qlen -= cl->un.leaf.q->q.qlen; + qlen = cl->un.leaf.q->q.qlen; qdisc_reset(cl->un.leaf.q); + qdisc_tree_decrease_qlen(cl->un.leaf.q, qlen); } if (cl->prio_activity) @@ -1419,8 +1425,11 @@ static int htb_change_class(struct Qdisc *sch, u32 classid, new_q = qdisc_create_dflt(sch->dev, &pfifo_qdisc_ops, classid); sch_tree_lock(sch); if (parent && !parent->level) { + unsigned int qlen = parent->un.leaf.q->q.qlen; + /* turn parent into inner node */ - sch->q.qlen -= parent->un.leaf.q->q.qlen; + qdisc_reset(parent->un.leaf.q); + qdisc_tree_decrease_qlen(parent->un.leaf.q, qlen); qdisc_destroy(parent->un.leaf.q); if (parent->prio_activity) htb_deactivate(q, parent); @@ -1568,6 +1577,7 @@ static void htb_walk(struct Qdisc *sch, struct qdisc_walker *arg) static struct Qdisc_class_ops htb_class_ops = { .graft = htb_graft, .leaf = htb_leaf, + .qlen_notify = htb_qlen_notify, .get = htb_get, .put = htb_put, .change = htb_change_class, -- 2.41.1