net-sched: sch_htb: remove child and sibling lists
Now that the qdisc isn't destroyed in hierarchical order anymore,
the only user of the child lists left is htb_parent_last_child().
This can be easily changed to use a counter of children to save
a few bytes.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/sched/sch_htb.c b/net/sched/sch_htb.c
index e7461a1..128a5ab 100644
--- a/net/sched/sch_htb.c
+++ b/net/sched/sch_htb.c
@@ -81,9 +81,8 @@
/* topology */
int level; /* our level (see above) */
+ unsigned int children;
struct htb_class *parent; /* parent class */
- struct list_head sibling; /* sibling list item */
- struct list_head children; /* children list */
union {
struct htb_class_leaf {
@@ -138,7 +137,6 @@
}
struct htb_sched {
- struct list_head root; /* root classes list */
struct Qdisc_class_hash clhash;
struct list_head drops[TC_HTB_NUMPRIO];/* active leaves (for drops) */
@@ -1020,7 +1018,6 @@
return -EINVAL;
}
- INIT_LIST_HEAD(&q->root);
err = qdisc_class_hash_init(&q->clhash);
if (err < 0)
return err;
@@ -1175,12 +1172,9 @@
if (!cl->parent)
/* the root class */
return 0;
-
- if (!(cl->parent->children.next == &cl->sibling &&
- cl->parent->children.prev == &cl->sibling))
+ if (cl->parent->children > 1)
/* not the last child */
return 0;
-
return 1;
}
@@ -1259,7 +1253,7 @@
// TODO: why don't allow to delete subtree ? references ? does
// tc subsys quarantee us that in htb_destroy it holds no class
// refs so that we can remove children safely there ?
- if (!list_empty(&cl->children) || cl->filter_cnt)
+ if (cl->children || cl->filter_cnt)
return -EBUSY;
if (!cl->level && htb_parent_last_child(cl)) {
@@ -1278,7 +1272,7 @@
/* delete from hash and active; remainder in destroy_class */
qdisc_class_hash_remove(&q->clhash, &cl->common);
- list_del(&cl->sibling);
+ cl->parent->children--;
if (cl->prio_activity)
htb_deactivate(q, cl);
@@ -1373,8 +1367,7 @@
&sch->dev->queue_lock,
tca[TCA_RATE] ? : &est.nla);
cl->refcnt = 1;
- INIT_LIST_HEAD(&cl->sibling);
- INIT_LIST_HEAD(&cl->children);
+ cl->children = 0;
INIT_LIST_HEAD(&cl->un.leaf.drop_list);
RB_CLEAR_NODE(&cl->pq_node);
@@ -1420,8 +1413,8 @@
/* attach to the hash list and parent's family */
qdisc_class_hash_insert(&q->clhash, &cl->common);
- list_add_tail(&cl->sibling,
- parent ? &parent->children : &q->root);
+ if (parent)
+ parent->children++;
} else {
if (tca[TCA_RATE])
gen_replace_estimator(&cl->bstats, &cl->rate_est,