timers: move timer calls out of hot loop

We sacrifice a little bit of precision here, but this avoids jockeying
around the timers for every packet, when we're sending in bundles anyway
to minimize cache misses.

Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>

1 files changed, 6 insertions, 3 deletions

diff --git a/src/send.c b/src/send.c
index 6992fd4..b9a95ac 100644
--- a/src/send.c
+++ b/src/send.c
@@ -132,16 +132,19 @@ struct packet_bundle {
 static inline void send_off_bundle(struct packet_bundle *bundle, struct wireguard_peer *peer)
 {
 	struct sk_buff *skb, *next;
-	bool is_keepalive;
+	bool is_keepalive, data_sent = false;
+	if (likely(bundle->first))
+		timers_any_authenticated_packet_traversal(peer);
 	for (skb = bundle->first; skb; skb = next) {
 		/* We store the next pointer locally because socket_send_skb_to_peer
 		 * consumes the packet before the top of the loop comes again. */
 		next = skb->next;
 		is_keepalive = skb->len == message_data_len(0);
-		timers_any_authenticated_packet_traversal(peer);
 		if (likely(!socket_send_skb_to_peer(peer, skb, 0 /* TODO: Should we copy the DSCP value from the enclosed packet? */) && !is_keepalive))
-			timers_data_sent(peer);
+			data_sent = true;
 	}
+	if (likely(data_sent))
+		timers_data_sent(peer);
 }
 
 static void message_create_data_done(struct sk_buff *skb, struct wireguard_peer *peer)