Subject: [PATCH 2/2] netlink: wake up netlink listeners sooner (v2)

From: Stephen Hemminger <[email-masked]>
Date: Thu, 22 Dec 2011 10:52:03 -0800

This patch changes it to yield sooner at halfway instead. Still not a cure-all
for listener overrun if listner is slow, but works much reliably.

Signed-off-by: Stephen Hemminger <[email-masked]>

---
v2 - use shift to avoid expensive integer division

--- a/net/netlink/af_netlink.c	2011-12-21 15:15:09.446373421 -0800
+++ b/net/netlink/af_netlink.c	2011-12-21 15:22:35.632062577 -0800
@@ -959,7 +959,7 @@ static int netlink_broadcast_deliver(str
 		skb_set_owner_r(skb, sk);
 		skb_queue_tail(&sk->sk_receive_queue, skb);
 		sk->sk_data_ready(sk, skb->len);
-		return atomic_read(&sk->sk_rmem_alloc) > sk->sk_rcvbuf;
+		return atomic_read(&sk->sk_rmem_alloc) > (sk->sk_rcvbuf >> 1);
 	}
 	return -1;
 }