mac80211: add client mode connection monitor fix

Signed-off-by: Felix Fietkau <nbd@nbd.name>

package/kernel/mac80211/patches/subsys/374-mac80211-fix-time-is-after-bug-in-mlme.patch

@@ -0,0 +1,31 @@
+From: Ben Greear <greearb@candelatech.com>
+Date: Tue, 30 Mar 2021 16:07:49 -0700
+Subject: [PATCH] mac80211: fix time-is-after bug in mlme
+
+The incorrect timeout check caused probing to happen when it did
+not need to happen.  This in turn caused tx performance drop
+for around 5 seconds in ath10k-ct driver.  Possibly that tx drop
+is due to a secondary issue, but fixing the probe to not happen
+when traffic is running fixes the symptom.
+
+Signed-off-by: Ben Greear <greearb@candelatech.com>
+Fixes: 9abf4e49830d ("mac80211: optimize station connection monitor")
+Acked-by: Felix Fietkau <nbd@nbd.name>
+Link: https://lore.kernel.org/r/20210330230749.14097-1-greearb@candelatech.com
+Signed-off-by: Johannes Berg <johannes.berg@intel.com>
+---
+
+--- a/net/mac80211/mlme.c
++++ b/net/mac80211/mlme.c
+@@ -4691,7 +4691,10 @@ static void ieee80211_sta_conn_mon_timer
+ 		timeout = sta->rx_stats.last_rx;
+ 	timeout += IEEE80211_CONNECTION_IDLE_TIME;
+ 
+-	if (time_is_before_jiffies(timeout)) {
++	/* If timeout is after now, then update timer to fire at
++	 * the later date, but do not actually probe at this time.
++	 */
++	if (time_is_after_jiffies(timeout)) {
+ 		mod_timer(&ifmgd->conn_mon_timer, round_jiffies_up(timeout));
+ 		return;
+ 	}