From: "Jason A. Donenfeld" <Jason@zx2c4.com>
Date: Fri, 14 Feb 2020 23:57:21 +0100
Subject: wireguard: receive: reset last_under_load to zero
Patch-mainline: v5.6-rc3
Git-commit: 2a8a4df36462aa85b0db87b7c5ea145ba67e34a8
References: bsc#1169021 jsc#SLE-12250

This is a small optimization that prevents more expensive comparisons
from happening when they are no longer necessary, by clearing the
last_under_load variable whenever we wind up in a state where we were
under load but we no longer are.

Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Suggested-by: Matt Dunwoodie <ncon@noconroy.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Acked-by: Nicolai Stange <nstange@suse.de>
---
 drivers/net/wireguard/receive.c |    7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

--- a/drivers/net/wireguard/receive.c
+++ b/drivers/net/wireguard/receive.c
@@ -118,10 +118,13 @@ static void wg_receive_handshake_packet(
 
 	under_load = skb_queue_len(&wg->incoming_handshakes) >=
 		     MAX_QUEUED_INCOMING_HANDSHAKES / 8;
-	if (under_load)
+	if (under_load) {
 		last_under_load = ktime_get_coarse_boottime_ns();
-	else if (last_under_load)
+	} else if (last_under_load) {
 		under_load = !wg_birthdate_has_expired(last_under_load, 1);
+		if (!under_load)
+			last_under_load = 0;
+	}
 	mac_state = wg_cookie_validate_packet(&wg->cookie_checker, skb,
 					      under_load);
 	if ((under_load && mac_state == VALID_MAC_WITH_COOKIE) ||