[PATCH net-next] net/sched: sch_ets: properly init all active DRR list handles
From: Davide Caratti <hidden>
Date: 2021-10-07 13:05:24
Subsystem:
networking [general], tc subsystem, the rest · Maintainers:
"David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Jamal Hadi Salim, Jiri Pirko, Linus Torvalds
leaf classes of ETS qdiscs are served in strict priority or deficit round robin (DRR), depending on the value of 'nstrict'. Since this value can be changed while traffic is running, we need to be sure that the active list of DRR classes can be updated at any time, so: 1) call INIT_LIST_HEAD(&alist) on all leaf classes in .init(), before the first packet hits any of them. 2) ensure that 'alist' is not overwritten with zeros when a leaf class is no more strict priority nor DRR (i.e. array elements beyond 'nbands'). Link: https://lore.kernel.org/netdev/YS%2FoZ+f0Nr8eQkzH@dcaratti.users.ipa.redhat.com (local) Suggested-by: Cong Wang <redacted> Signed-off-by: Davide Caratti <redacted> --- net/sched/sch_ets.c | 12 +++++++++--- 1 file changed, 9 insertions(+), 3 deletions(-)
diff --git a/net/sched/sch_ets.c b/net/sched/sch_ets.c
index 1f857ffd1ac2..ed86b7021f6d 100644
--- a/net/sched/sch_ets.c
+++ b/net/sched/sch_ets.c@@ -661,7 +661,6 @@ static int ets_qdisc_change(struct Qdisc *sch, struct nlattr *opt, q->nbands = nbands; for (i = nstrict; i < q->nstrict; i++) { - INIT_LIST_HEAD(&q->classes[i].alist); if (q->classes[i].qdisc->q.qlen) { list_add_tail(&q->classes[i].alist, &q->active); q->classes[i].deficit = quanta[i];
@@ -687,7 +686,11 @@ static int ets_qdisc_change(struct Qdisc *sch, struct nlattr *opt, ets_offload_change(sch); for (i = q->nbands; i < oldbands; i++) { qdisc_put(q->classes[i].qdisc); - memset(&q->classes[i], 0, sizeof(q->classes[i])); + q->classes[i].qdisc = NULL; + q->classes[i].quantum = 0; + q->classes[i].deficit = 0; + memset(&q->classes[i].bstats, 0, sizeof(q->classes[i].bstats)); + memset(&q->classes[i].qstats, 0, sizeof(q->classes[i].qstats)); } return 0; }
@@ -696,7 +699,7 @@ static int ets_qdisc_init(struct Qdisc *sch, struct nlattr *opt, struct netlink_ext_ack *extack) { struct ets_sched *q = qdisc_priv(sch); - int err; + int err, i; if (!opt) return -EINVAL;
@@ -706,6 +709,9 @@ static int ets_qdisc_init(struct Qdisc *sch, struct nlattr *opt, return err; INIT_LIST_HEAD(&q->active); + for (i = 0; i < TCQ_ETS_MAX_BANDS; i++) + INIT_LIST_HEAD(&q->classes[i].alist); + return ets_qdisc_change(sch, opt, extack); }
--
2.31.1