Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 3696f625 authored by Stephen Hemminger's avatar Stephen Hemminger Committed by David S. Miller
Browse files

[HTB]: rbtree cleanup 

Add code to initialize rb tree nodes, and check for double deletion.
This is not a real fix, but I can make it trap sometimes and may
be a bandaid for: http://bugzilla.kernel.org/show_bug.cgi?id=6681



Signed-off-by: default avatarStephen Hemminger <shemminger@osdl.org>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 0cef296d

net/sched/sch_htb.c

+27 −7
Original line number Diff line number Diff line
@@ -366,7 +366,7 @@ static void htb_add_to_wait_tree(struct htb_sched *q, 
 * When we are past last key we return NULL.

 * Average complexity is 2 steps per call.

 */

static void htb_next_rb_node(struct rb_node **n)

static inline void htb_next_rb_node(struct rb_node **n)

{

	*n = rb_next(*n);

}
@@ -388,6 +388,18 @@ static inline void htb_add_class_to_row(struct htb_sched *q, 
	}

}



/* If this triggers, it is a bug in this code, but it need not be fatal */

static void htb_safe_rb_erase(struct rb_node *rb, struct rb_root *root)

{

	if (RB_EMPTY_NODE(rb)) {

		WARN_ON(1);

	} else {

		rb_erase(rb, root);

		RB_CLEAR_NODE(rb);

	}

}





/**

 * htb_remove_class_from_row - removes class from its row

 *
@@ -401,10 +413,12 @@ static inline void htb_remove_class_from_row(struct htb_sched *q, 


	while (mask) {

		int prio = ffz(~mask);



		mask &= ~(1 << prio);

		if (q->ptr[cl->level][prio] == cl->node + prio)

			htb_next_rb_node(q->ptr[cl->level] + prio);

		rb_erase(cl->node + prio, q->row[cl->level] + prio);



		htb_safe_rb_erase(cl->node + prio, q->row[cl->level] + prio);

		if (!q->row[cl->level][prio].rb_node)

			m |= 1 << prio;

	}
@@ -472,7 +486,7 @@ static void htb_deactivate_prios(struct htb_sched *q, struct htb_class *cl) 
				p->un.inner.ptr[prio] = NULL;

			}



			rb_erase(cl->node + prio, p->un.inner.feed + prio);

			htb_safe_rb_erase(cl->node + prio, p->un.inner.feed + prio);



			if (!p->un.inner.feed[prio].rb_node)

				mask |= 1 << prio;
@@ -739,7 +753,7 @@ static void htb_charge_class(struct htb_sched *q, struct htb_class *cl, 
		htb_change_class_mode(q, cl, &diff);

		if (old_mode != cl->cmode) {

			if (old_mode != HTB_CAN_SEND)

				rb_erase(&cl->pq_node, q->wait_pq + cl->level);

				htb_safe_rb_erase(&cl->pq_node, q->wait_pq + cl->level);

			if (cl->cmode != HTB_CAN_SEND)

				htb_add_to_wait_tree(q, cl, diff);

		}
@@ -782,7 +796,7 @@ static long htb_do_events(struct htb_sched *q, int level) 
		if (time_after(cl->pq_key, q->jiffies)) {

			return cl->pq_key - q->jiffies;

		}

		rb_erase(p, q->wait_pq + level);

		htb_safe_rb_erase(p, q->wait_pq + level);

		diff = PSCHED_TDIFF_SAFE(q->now, cl->t_c, (u32) cl->mbuffer);

		htb_change_class_mode(q, cl, &diff);

		if (cl->cmode != HTB_CAN_SEND)
@@ -1279,7 +1293,7 @@ static void htb_destroy_class(struct Qdisc *sch, struct htb_class *cl) 
		htb_deactivate(q, cl);



	if (cl->cmode != HTB_CAN_SEND)

		rb_erase(&cl->pq_node, q->wait_pq + cl->level);

		htb_safe_rb_erase(&cl->pq_node, q->wait_pq + cl->level);



	kfree(cl);

}
@@ -1370,6 +1384,8 @@ static int htb_change_class(struct Qdisc *sch, u32 classid, 


	if (!cl) {		/* new class */

		struct Qdisc *new_q;

		int prio;



		/* check for valid classid */

		if (!classid || TC_H_MAJ(classid ^ sch->handle)

		    || htb_find(classid, sch))
@@ -1389,6 +1405,10 @@ static int htb_change_class(struct Qdisc *sch, u32 classid, 
		INIT_HLIST_NODE(&cl->hlist);

		INIT_LIST_HEAD(&cl->children);

		INIT_LIST_HEAD(&cl->un.leaf.drop_list);

		RB_CLEAR_NODE(&cl->pq_node);



		for (prio = 0; prio < TC_HTB_NUMPRIO; prio++)

			RB_CLEAR_NODE(&cl->node[prio]);



		/* create leaf qdisc early because it uses kmalloc(GFP_KERNEL)

		   so that can't be used inside of sch_tree_lock
@@ -1404,7 +1424,7 @@ static int htb_change_class(struct Qdisc *sch, u32 classid, 


			/* remove from evt list because of level change */

			if (parent->cmode != HTB_CAN_SEND) {

				rb_erase(&parent->pq_node, q->wait_pq);

				htb_safe_rb_erase(&parent->pq_node, q->wait_pq);

				parent->cmode = HTB_CAN_SEND;

			}

			parent->level = (parent->parent ? parent->parent->level