From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: [PATCH 3/3] netlink: wake up netlink listeners sooner
Date: Wed, 21 Dec 2011 18:00:11 -0500 (EST)
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From: Stephen Hemminger <shemminger@vyatta.com>
Date: Wed, 21 Dec 2011 13:49:44 -0800

> @@ -960,7 +960,7 @@ 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 / 2;
>  	}

Please mirror the logic we use in the generic socket code to do this
on the send side, namely use something like:

		return (atomic_read(&sk->sk_rmem_alloc) << 1) > sk->sk_rcvbuf;

because sk_rcvbuf is an int and this "/ 2" expression will generate a
really silly sequence of multiple shifts, adds, and comparisons in
order to handle negative values correctly.