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Diffstat (limited to 'net/sched/sch_taprio.c')
-rw-r--r--net/sched/sch_taprio.c27
1 files changed, 22 insertions, 5 deletions
diff --git a/net/sched/sch_taprio.c b/net/sched/sch_taprio.c
index 8623dc0bafc0..1620f0fd78ce 100644
--- a/net/sched/sch_taprio.c
+++ b/net/sched/sch_taprio.c
@@ -43,6 +43,11 @@ static struct static_key_false taprio_have_working_mqprio;
#define TAPRIO_SUPPORTED_FLAGS \
(TCA_TAPRIO_ATTR_FLAG_TXTIME_ASSIST | TCA_TAPRIO_ATTR_FLAG_FULL_OFFLOAD)
#define TAPRIO_FLAGS_INVALID U32_MAX
+/* Minimum value for picos_per_byte to ensure non-zero duration
+ * for minimum-sized Ethernet frames (ETH_ZLEN = 60).
+ * 60 * 17 > PSEC_PER_NSEC (1000)
+ */
+#define TAPRIO_PICOS_PER_BYTE_MIN 17
struct sched_entry {
/* Durations between this GCL entry and the GCL entry where the
@@ -1284,7 +1289,8 @@ static void taprio_start_sched(struct Qdisc *sch,
}
static void taprio_set_picos_per_byte(struct net_device *dev,
- struct taprio_sched *q)
+ struct taprio_sched *q,
+ struct netlink_ext_ack *extack)
{
struct ethtool_link_ksettings ecmd;
int speed = SPEED_10;
@@ -1300,6 +1306,15 @@ static void taprio_set_picos_per_byte(struct net_device *dev,
skip:
picos_per_byte = (USEC_PER_SEC * 8) / speed;
+ if (picos_per_byte < TAPRIO_PICOS_PER_BYTE_MIN) {
+ if (!extack)
+ pr_warn("Link speed %d is too high. Schedule may be inaccurate.\n",
+ speed);
+ NL_SET_ERR_MSG_FMT_MOD(extack,
+ "Link speed %d is too high. Schedule may be inaccurate.",
+ speed);
+ picos_per_byte = TAPRIO_PICOS_PER_BYTE_MIN;
+ }
atomic64_set(&q->picos_per_byte, picos_per_byte);
netdev_dbg(dev, "taprio: set %s's picos_per_byte to: %lld, linkspeed: %d\n",
@@ -1324,17 +1339,19 @@ static int taprio_dev_notifier(struct notifier_block *nb, unsigned long event,
if (dev != qdisc_dev(q->root))
continue;
- taprio_set_picos_per_byte(dev, q);
+ taprio_set_picos_per_byte(dev, q, NULL);
stab = rtnl_dereference(q->root->stab);
- oper = rtnl_dereference(q->oper_sched);
+ rcu_read_lock();
+ oper = rcu_dereference(q->oper_sched);
if (oper)
taprio_update_queue_max_sdu(q, oper, stab);
- admin = rtnl_dereference(q->admin_sched);
+ admin = rcu_dereference(q->admin_sched);
if (admin)
taprio_update_queue_max_sdu(q, admin, stab);
+ rcu_read_unlock();
break;
}
@@ -1846,7 +1863,7 @@ static int taprio_change(struct Qdisc *sch, struct nlattr *opt,
q->flags = taprio_flags;
/* Needed for length_to_duration() during netlink attribute parsing */
- taprio_set_picos_per_byte(dev, q);
+ taprio_set_picos_per_byte(dev, q, extack);
err = taprio_parse_mqprio_opt(dev, mqprio, extack, q->flags);
if (err < 0)