From mboxrd@z Thu Jan  1 00:00:00 1970
From: Eric Dumazet <eric.dumazet@gmail.com>
Subject: Re: [RFC] sched: CHOKe packet scheduler
Date: Wed, 05 Jan 2011 07:19:35 +0100
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References: <20110104162930.6fa672e3@nehalam>
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Cc: David Miller <davem@davemloft.net>, netdev@vger.kernel.org
To: Stephen Hemminger <shemminger@vyatta.com>
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Le mardi 04 janvier 2011 =C3=A0 16:29 -0800, Stephen Hemminger a =C3=A9=
crit :
> +static struct sk_buff *skb_peek_random(struct sk_buff_head *list)
> +{
> +	struct sk_buff *skb =3D list->next;
> +	unsigned int idx =3D net_random() % list->qlen;
> +
> +	while (skb && idx-- > 0)
> +		skb =3D skb->next;
> +
> +	return skb;
> +}

You could avoid the divide op :

unsigned int idx =3D reciprocal_divide(random32(), list->qlen);