wifi: mac80211: switch airtime fairness back to deficit round-robin scheduling

This reverts commits 6a789ba679d652587532cec2a0e0274fda172f3b and
2433647bc8d983a543e7d31b41ca2de1c7e2c198.

The virtual time scheduler code has a number of issues:
- queues slowed down by hardware/firmware powersave handling were not properly
  handled.
- on ath10k in push-pull mode, tx queues that the driver tries to pull from
  were starved, causing excessive latency
- delay between tx enqueue and reported airtime use were causing excessively
  bursty tx behavior

The bursty behavior may also be present on the round-robin scheduler, but there
it is much easier to fix without introducing additional regressions

Signed-off-by: Felix Fietkau <nbd@nbd.name>
Acked-by: Toke Høiland-Jørgensen <toke@toke.dk>
Link: https://lore.kernel.org/r/20220625212411.36675-1-nbd@nbd.name
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

1 files changed, 0 insertions, 4 deletions

diff --git a/net/mac80211/iface.c b/net/mac80211/iface.c
index 0cf5a395d925..56dd831fe45f 100644
--- a/net/mac80211/iface.c
+++ b/net/mac80211/iface.c
@@ -2176,10 +2176,6 @@ int ieee80211_if_add(struct ieee80211_local *local, const char *name,
 		}
 	}
 
-	for (i = 0; i < IEEE80211_NUM_ACS; i++)
-		init_airtime_info(&sdata->deflink.airtime[i],
-				  &local->airtime[i]);
-
 	ieee80211_set_default_queues(sdata);
 
 	sdata->deflink.ap_power_level = IEEE80211_UNSET_POWER_LEVEL;