wifi: mac80211: fix mesh airtime link metric estimating

ieee80211s_update_metric function uses sta_set_rate_info_tx
function to get struct rate_info data from ieee80211_tx_rate
struct, present in ieee80211_sta->deflink.tx_stats. However,
drivers can skip tx rate calculation by setting rate idx as
-1. Such drivers provides rate_info directly and hence
ieee80211s metric is updated incorrectly since ieee80211_tx_rate
has inconsistent data.

Add fix to use rate_info directly if present instead of
sta_set_rate_info_tx for updating ieee80211s metric.

Signed-off-by: Aditya Kumar Singh <quic_adisi@quicinc.com>
Link: https://lore.kernel.org/r/20220701133611.544-1-quic_adisi@quicinc.com
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

diff --git a/net/mac80211/mesh_hwmp.c b/net/mac80211/mesh_hwmp.c
index 45e7c1b307bc6d53a416baac65a981ade304da16..7fd269cbb01a1dc1212311215bfc3911fa6bdf3f 100644 (file)
--- a/net/mac80211/mesh_hwmp.c
+++ b/net/mac80211/mesh_hwmp.c
@@ -310,7 +310,12 @@ void ieee80211s_update_metric(struct ieee80211_local *local,
                        LINK_FAIL_THRESH)
                mesh_plink_broken(sta);
 
-       sta_set_rate_info_tx(sta, &sta->deflink.tx_stats.last_rate, &rinfo);
+       /* use rate info set by the driver directly if present */
+       if (st->n_rates)
+               rinfo = sta->deflink.tx_stats.last_rate_info;
+       else
+               sta_set_rate_info_tx(sta, &sta->deflink.tx_stats.last_rate, &rinfo);
+
        ewma_mesh_tx_rate_avg_add(&sta->mesh->tx_rate_avg,
                                  cfg80211_calculate_bitrate(&rinfo));
 }