From 4873a1b2024dce9a501b56d1039ff0752027a92e Mon Sep 17 00:00:00 2001 From: Vladimir Oltean Date: Sun, 31 Jul 2022 15:41:06 +0300 Subject: [PATCH] net/sched: remove hacks added to dev_trans_start() for bonding to work Now that the bonding driver keeps track of the last TX time of ARP and NS probes, we effectively revert the following commits: 32d3e51a82d4 ("net_sched: use macvlan real dev trans_start in dev_trans_start()") 07ce76aa9bcf ("net_sched: make dev_trans_start return vlan's real dev trans_start") Note that the approach of continuing to hack at this function would not get us very far, hence the desire to take a different approach. DSA is also a virtual device that uses NETIF_F_LLTX, but there, many uppers share the same lower (DSA master, i.e. the physical host port of a switch). By making dev_trans_start() on a DSA interface return the dev_trans_start() of the master, we effectively assume that all other DSA interfaces are silent, otherwise this corrupts the validity of the probe timestamp data from the bonding driver's perspective. Furthermore, the hacks didn't take into consideration the fact that the lower interface of @dev may not have been physical either. For example, VLAN over VLAN, or DSA with 2 masters in a LAG. And even furthermore, there are NETIF_F_LLTX devices which are not stacked, like veth. The hack here would not work with those, because it would not have to provide the bonding driver something to chew at all. Signed-off-by: Vladimir Oltean Signed-off-by: Jakub Kicinski --- net/sched/sch_generic.c | 8 ++------ 1 file changed, 2 insertions(+), 6 deletions(-) diff --git a/net/sched/sch_generic.c b/net/sched/sch_generic.c index cc6eabee2830..d47b9689eba6 100644 --- a/net/sched/sch_generic.c +++ b/net/sched/sch_generic.c @@ -427,14 +427,10 @@ void __qdisc_run(struct Qdisc *q) unsigned long dev_trans_start(struct net_device *dev) { - unsigned long val, res; + unsigned long res = READ_ONCE(netdev_get_tx_queue(dev, 0)->trans_start); + unsigned long val; unsigned int i; - if (is_vlan_dev(dev)) - dev = vlan_dev_real_dev(dev); - else if (netif_is_macvlan(dev)) - dev = macvlan_dev_real_dev(dev); - res = READ_ONCE(netdev_get_tx_queue(dev, 0)->trans_start); for (i = 1; i < dev->num_tx_queues; i++) { val = READ_ONCE(netdev_get_tx_queue(dev, i)->trans_start); if (val && time_after(val, res)) -- 2.11.0