Commit e5f0e8f8 authored by Paolo Abeni's avatar Paolo Abeni Committed by David S. Miller
Browse files

net: sched: introduce and use qdisc tree flush/purge helpers 



The same code to flush qdisc tree and purge the qdisc queue
is duplicated in many places and in most cases it does not
respect NOLOCK qdisc: the global backlog len is used and the
per CPU values are ignored.

This change addresses the above, factoring-out the relevant
code and using the helpers introduced by the previous patch
to fetch the correct backlog len.

Fixes: c5ad119f ("net: sched: pfifo_fast use skb_array")
Signed-off-by: default avatarPaolo Abeni <pabeni@redhat.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 5dd431b6

include/net/sch_generic.h

+19 −7
Original line number Diff line number Diff line
@@ -941,6 +941,23 @@ static inline void qdisc_qstats_qlen_backlog(struct Qdisc *sch, __u32 *qlen, 
	*backlog = qstats.backlog;

}



static inline void qdisc_tree_flush_backlog(struct Qdisc *sch)

{

	__u32 qlen, backlog;



	qdisc_qstats_qlen_backlog(sch, &qlen, &backlog);

	qdisc_tree_reduce_backlog(sch, qlen, backlog);

}



static inline void qdisc_purge_queue(struct Qdisc *sch)

{

	__u32 qlen, backlog;



	qdisc_qstats_qlen_backlog(sch, &qlen, &backlog);

	qdisc_reset(sch);

	qdisc_tree_reduce_backlog(sch, qlen, backlog);

}



static inline void qdisc_skb_head_init(struct qdisc_skb_head *qh)

{

	qh->head = NULL;
@@ -1124,13 +1141,8 @@ static inline struct Qdisc *qdisc_replace(struct Qdisc *sch, struct Qdisc *new, 
	sch_tree_lock(sch);

	old = *pold;

	*pold = new;

	if (old != NULL) {

		unsigned int qlen = old->q.qlen;

		unsigned int backlog = old->qstats.backlog;



		qdisc_reset(old);

		qdisc_tree_reduce_backlog(old, qlen, backlog);

	}

	if (old != NULL)

		qdisc_tree_flush_backlog(old);

	sch_tree_unlock(sch);



	return old;

net/sched/sch_cbq.c

+1 −5
Original line number Diff line number Diff line
@@ -1667,17 +1667,13 @@ static int cbq_delete(struct Qdisc *sch, unsigned long arg) 
{

	struct cbq_sched_data *q = qdisc_priv(sch);

	struct cbq_class *cl = (struct cbq_class *)arg;

	unsigned int qlen, backlog;



	if (cl->filters || cl->children || cl == &q->link)

		return -EBUSY;



	sch_tree_lock(sch);



	qlen = cl->q->q.qlen;

	backlog = cl->q->qstats.backlog;

	qdisc_reset(cl->q);

	qdisc_tree_reduce_backlog(cl->q, qlen, backlog);

	qdisc_purge_queue(cl->q);



	if (cl->next_alive)

		cbq_deactivate_class(cl);

net/sched/sch_drr.c

+1 −10
Original line number Diff line number Diff line
@@ -50,15 +50,6 @@ static struct drr_class *drr_find_class(struct Qdisc *sch, u32 classid) 
	return container_of(clc, struct drr_class, common);

}



static void drr_purge_queue(struct drr_class *cl)

{

	unsigned int len = cl->qdisc->q.qlen;

	unsigned int backlog = cl->qdisc->qstats.backlog;



	qdisc_reset(cl->qdisc);

	qdisc_tree_reduce_backlog(cl->qdisc, len, backlog);

}



static const struct nla_policy drr_policy[TCA_DRR_MAX + 1] = {

	[TCA_DRR_QUANTUM]	= { .type = NLA_U32 },

};
@@ -167,7 +158,7 @@ static int drr_delete_class(struct Qdisc *sch, unsigned long arg) 


	sch_tree_lock(sch);



	drr_purge_queue(cl);

	qdisc_purge_queue(cl->qdisc);

	qdisc_class_hash_remove(&q->clhash, &cl->common);



	sch_tree_unlock(sch);

net/sched/sch_hfsc.c

+2 −12
Original line number Diff line number Diff line
@@ -844,16 +844,6 @@ qdisc_peek_len(struct Qdisc *sch) 
	return len;

}



static void

hfsc_purge_queue(struct Qdisc *sch, struct hfsc_class *cl)

{

	unsigned int len = cl->qdisc->q.qlen;

	unsigned int backlog = cl->qdisc->qstats.backlog;



	qdisc_reset(cl->qdisc);

	qdisc_tree_reduce_backlog(cl->qdisc, len, backlog);

}



static void

hfsc_adjust_levels(struct hfsc_class *cl)

{
@@ -1076,7 +1066,7 @@ hfsc_change_class(struct Qdisc *sch, u32 classid, u32 parentid, 
	qdisc_class_hash_insert(&q->clhash, &cl->cl_common);

	list_add_tail(&cl->siblings, &parent->children);

	if (parent->level == 0)

		hfsc_purge_queue(sch, parent);

		qdisc_purge_queue(parent->qdisc);

	hfsc_adjust_levels(parent);

	sch_tree_unlock(sch);
@@ -1112,7 +1102,7 @@ hfsc_delete_class(struct Qdisc *sch, unsigned long arg) 
	list_del(&cl->siblings);

	hfsc_adjust_levels(cl->cl_parent);



	hfsc_purge_queue(sch, cl);

	qdisc_purge_queue(cl->qdisc);

	qdisc_class_hash_remove(&q->clhash, &cl->cl_common);



	sch_tree_unlock(sch);

net/sched/sch_htb.c

+3 −12
Original line number Diff line number Diff line
@@ -1269,13 +1269,8 @@ static int htb_delete(struct Qdisc *sch, unsigned long arg) 


	sch_tree_lock(sch);



	if (!cl->level) {

		unsigned int qlen = cl->leaf.q->q.qlen;

		unsigned int backlog = cl->leaf.q->qstats.backlog;



		qdisc_reset(cl->leaf.q);

		qdisc_tree_reduce_backlog(cl->leaf.q, qlen, backlog);

	}

	if (!cl->level)

		qdisc_purge_queue(cl->leaf.q);



	/* delete from hash and active; remainder in destroy_class */

	qdisc_class_hash_remove(&q->clhash, &cl->common);
@@ -1403,12 +1398,8 @@ static int htb_change_class(struct Qdisc *sch, u32 classid, 
					  classid, NULL);

		sch_tree_lock(sch);

		if (parent && !parent->level) {

			unsigned int qlen = parent->leaf.q->q.qlen;

			unsigned int backlog = parent->leaf.q->qstats.backlog;



			/* turn parent into inner node */

			qdisc_reset(parent->leaf.q);

			qdisc_tree_reduce_backlog(parent->leaf.q, qlen, backlog);

			qdisc_purge_queue(parent->leaf.q);

			qdisc_put(parent->leaf.q);

			if (parent->prio_activity)

				htb_deactivate(q, parent);

CRA Git | Maintained and supported by SUSTech CRA and CCSE