From:   Karthik M <quic_karm@quicinc.com>
To:     <johannes@sipsolutions.net>
CC:     <linux-wireless@vger.kernel.org>,
        Karthik M <quic_karm@quicinc.com>,
        Tamizh Chelvam Raja <quic_tamizhr@quicinc.com>
Subject: [PATCH] wifi: mac80211: Initialize EWMA fail avg to 1
Date:   Fri, 17 Mar 2023 20:14:32 +0530
Message-ID: <20230317144432.10477-1-quic_karm@quicinc.com>
MIME-Version: 1.0
Content-Type: text/plain
Precedence: bulk

If the average value has been rounded to 0 (success),
reset it to the smallest nonzero value (similarly to the initialization) to
avoid a case where a single failure would result in an average value
that goes beyond the threshold value of 95.

Signed-off-by: Tamizh Chelvam Raja <quic_tamizhr@quicinc.com>
Signed-off-by: Karthik M <quic_karm@quicinc.com>
---
 net/mac80211/mesh_hwmp.c | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/net/mac80211/mesh_hwmp.c b/net/mac80211/mesh_hwmp.c
index 9b1ce7c3925a..e9fcaff9cc7e 100644
--- a/net/mac80211/mesh_hwmp.c
+++ b/net/mac80211/mesh_hwmp.c
@@ -298,10 +298,21 @@ void ieee80211s_update_metric(struct ieee80211_local *local,
 {
 	struct ieee80211_tx_info *txinfo = st->info;
 	int failed;
+	u32 fail_avg;
 	struct rate_info rinfo;
 
 	failed = !(txinfo->flags & IEEE80211_TX_STAT_ACK);
 
+	fail_avg = ewma_mesh_fail_avg_read(&sta->mesh->fail_avg);
+	if (!fail_avg) {
+		/* If the average value has been rounded to 0 (success), 
+		 * reset it to the smallest nonzero value (similarly to 
+		 * the initialization) to avoid a case where a single 
+		 * failure would result in an average value that goes 
+		 * beyond the threshold value of 95 */
+		ewma_mesh_fail_avg_add(&sta->mesh->fail_avg, 1);
+	}
+
 	/* moving average, scaled to 100.
 	 * feed failure as 100 and success as 0
 	 */
-- 
2.17.1