[PATCH] net: sched: make default fifo qdiscs appear in the dump

From: Jiri Kosina
Date: Fri Oct 21 2016 - 04:45:49 EST


The original reason [1] for having hidden qdiscs (potential scalability
issues in qdisc_match_from_root() with single linked list in case of large
amount of qdiscs) has been invalidated by 59cc1f61f0 ("net: sched: convert
qdisc linked list to hashtable").

This allows us for bringing more clarity and determinism into the dump by
making default pfifo qdiscs visible.

[1] http://lkml.kernel.org/r/1460732328.10638.74.camel@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx

Signed-off-by: Jiri Kosina <jkosina@xxxxxxx>
---

Tested for cbq, htb and tbf.

net/sched/sch_cbq.c | 4 ++++
net/sched/sch_drr.c | 2 ++
net/sched/sch_dsmark.c | 1 +
net/sched/sch_hfsc.c | 2 ++
net/sched/sch_htb.c | 1 +
net/sched/sch_multiq.c | 1 +
net/sched/sch_prio.c | 4 +++-
net/sched/sch_qfq.c | 1 +
net/sched/sch_red.c | 1 +
net/sched/sch_sfb.c | 1 +
net/sched/sch_tbf.c | 1 +
11 files changed, 18 insertions(+), 1 deletion(-)

diff --git a/net/sched/sch_cbq.c b/net/sched/sch_cbq.c
index beb554a..3c85e8d 100644
--- a/net/sched/sch_cbq.c
+++ b/net/sched/sch_cbq.c
@@ -1161,6 +1161,8 @@ static int cbq_init(struct Qdisc *sch, struct nlattr *opt)
if (!q->link.q)
q->link.q = &noop_qdisc;

+ qdisc_hash_add(q->link.q);
+
q->link.priority = TC_CBQ_MAXPRIO - 1;
q->link.priority2 = TC_CBQ_MAXPRIO - 1;
q->link.cpriority = TC_CBQ_MAXPRIO - 1;
@@ -1606,6 +1608,8 @@ static void cbq_put(struct Qdisc *sch, unsigned long arg)
cl->quantum = cl->allot;
cl->weight = cl->R_tab->rate.rate;

+ qdisc_hash_add(cl->q);
+
sch_tree_lock(sch);
cbq_link_class(cl);
cl->borrow = cl->tparent;
diff --git a/net/sched/sch_drr.c b/net/sched/sch_drr.c
index 8af5c59..1d33b94 100644
--- a/net/sched/sch_drr.c
+++ b/net/sched/sch_drr.c
@@ -118,6 +118,8 @@ static int drr_change_class(struct Qdisc *sch, u32 classid, u32 parentid,
if (cl->qdisc == NULL)
cl->qdisc = &noop_qdisc;

+ qdisc_hash_add(cl->qdisc);
+
if (tca[TCA_RATE]) {
err = gen_replace_estimator(&cl->bstats, NULL, &cl->rate_est,
NULL,
diff --git a/net/sched/sch_dsmark.c b/net/sched/sch_dsmark.c
index 1308bbf..d0bffd6 100644
--- a/net/sched/sch_dsmark.c
+++ b/net/sched/sch_dsmark.c
@@ -367,6 +367,7 @@ static int dsmark_init(struct Qdisc *sch, struct nlattr *opt)
p->q = qdisc_create_dflt(sch->dev_queue, &pfifo_qdisc_ops, sch->handle);
if (p->q == NULL)
p->q = &noop_qdisc;
+ qdisc_hash_add(p->q);

pr_debug("%s: qdisc %p\n", __func__, p->q);

diff --git a/net/sched/sch_hfsc.c b/net/sched/sch_hfsc.c
index 000f1d3..a75710e 100644
--- a/net/sched/sch_hfsc.c
+++ b/net/sched/sch_hfsc.c
@@ -1066,6 +1066,7 @@ struct hfsc_sched {
&pfifo_qdisc_ops, classid);
if (cl->qdisc == NULL)
cl->qdisc = &noop_qdisc;
+ qdisc_hash_add(cl->qdisc);
INIT_LIST_HEAD(&cl->children);
cl->vt_tree = RB_ROOT;
cl->cf_tree = RB_ROOT;
@@ -1425,6 +1426,7 @@ struct hfsc_sched {
sch->handle);
if (q->root.qdisc == NULL)
q->root.qdisc = &noop_qdisc;
+ qdisc_hash_add(q->root.qdisc);
INIT_LIST_HEAD(&q->root.children);
q->root.vt_tree = RB_ROOT;
q->root.cf_tree = RB_ROOT;
diff --git a/net/sched/sch_htb.c b/net/sched/sch_htb.c
index c798d0d..421d0a9 100644
--- a/net/sched/sch_htb.c
+++ b/net/sched/sch_htb.c
@@ -1459,6 +1459,7 @@ static int htb_change_class(struct Qdisc *sch, u32 classid,
qdisc_class_hash_insert(&q->clhash, &cl->common);
if (parent)
parent->children++;
+ qdisc_hash_add(cl->un.leaf.q);
} else {
if (tca[TCA_RATE]) {
err = gen_replace_estimator(&cl->bstats, NULL,
diff --git a/net/sched/sch_multiq.c b/net/sched/sch_multiq.c
index 9ffbb02..9266e9c 100644
--- a/net/sched/sch_multiq.c
+++ b/net/sched/sch_multiq.c
@@ -217,6 +217,7 @@ static int multiq_tune(struct Qdisc *sch, struct nlattr *opt)
sch_tree_lock(sch);
old = q->queues[i];
q->queues[i] = child;
+ qdisc_hash_add(child);

if (old != &noop_qdisc) {
qdisc_tree_reduce_backlog(old,
diff --git a/net/sched/sch_prio.c b/net/sched/sch_prio.c
index 8f57589..604a817 100644
--- a/net/sched/sch_prio.c
+++ b/net/sched/sch_prio.c
@@ -192,8 +192,10 @@ static int prio_tune(struct Qdisc *sch, struct nlattr *opt)
qdisc_destroy(child);
}

- for (i = oldbands; i < q->bands; i++)
+ for (i = oldbands; i < q->bands; i++) {
q->queues[i] = queues[i];
+ qdisc_hash_add(q->queues[i]);
+ }

sch_tree_unlock(sch);
return 0;
diff --git a/net/sched/sch_qfq.c b/net/sched/sch_qfq.c
index ca0516e..f29676c 100644
--- a/net/sched/sch_qfq.c
+++ b/net/sched/sch_qfq.c
@@ -494,6 +494,7 @@ static int qfq_change_class(struct Qdisc *sch, u32 classid, u32 parentid,
goto destroy_class;
}

+ qdisc_hash_add(cl->qdisc);
sch_tree_lock(sch);
qdisc_class_hash_insert(&q->clhash, &cl->common);
sch_tree_unlock(sch);
diff --git a/net/sched/sch_red.c b/net/sched/sch_red.c
index 249b2a1..cad2370 100644
--- a/net/sched/sch_red.c
+++ b/net/sched/sch_red.c
@@ -191,6 +191,7 @@ static int red_change(struct Qdisc *sch, struct nlattr *opt)
return PTR_ERR(child);
}

+ qdisc_hash_add(child);
sch_tree_lock(sch);
q->flags = ctl->flags;
q->limit = ctl->limit;
diff --git a/net/sched/sch_sfb.c b/net/sched/sch_sfb.c
index 20a350b..a0a9829 100644
--- a/net/sched/sch_sfb.c
+++ b/net/sched/sch_sfb.c
@@ -512,6 +512,7 @@ static int sfb_change(struct Qdisc *sch, struct nlattr *opt)
if (IS_ERR(child))
return PTR_ERR(child);

+ qdisc_hash_add(child);
sch_tree_lock(sch);

qdisc_tree_reduce_backlog(q->qdisc, q->qdisc->q.qlen,
diff --git a/net/sched/sch_tbf.c b/net/sched/sch_tbf.c
index 303355c..7e23392 100644
--- a/net/sched/sch_tbf.c
+++ b/net/sched/sch_tbf.c
@@ -396,6 +396,7 @@ static int tbf_change(struct Qdisc *sch, struct nlattr *opt)
q->qdisc->qstats.backlog);
qdisc_destroy(q->qdisc);
q->qdisc = child;
+ qdisc_hash_add(child);
}
q->limit = qopt->limit;
if (tb[TCA_TBF_PBURST])
--
Jiri Kosina
SUSE Labs