From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: [PATCH] tg3 : avoid an expensive divide
Date: Tue, 06 Feb 2007 13:25:58 -0800 (PST)
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From: "Michael Chan" <mchan@broadcom.com>
Date: Tue, 06 Feb 2007 14:05:41 -0800

> On Tue, 2007-02-06 at 21:53 +0100, Eric Dumazet wrote:
> 
> > Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
> > plain text document attachment (tg3_avoid_divide.patch)
> > --- linux-2.6.20/drivers/net/tg3.c.orig	2007-02-06 22:30:39.000000000 +0100
> > +++ linux-2.6.20-ed/drivers/net/tg3.c	2007-02-06 22:32:42.000000000 +0100
> > @@ -3384,7 +3384,7 @@
> >  		}
> >  next_pkt_nopost:
> >  		sw_idx++;
> > -		sw_idx %= TG3_RX_RCB_RING_SIZE(tp);
> > +		sw_idx &= (TG3_RX_RCB_RING_SIZE(tp) - 1);
> >  
> >  		/* Refresh hw_idx to see if there is new work */
> >  		if (sw_idx == hw_idx) {
> 
> There are other places doing similar divide (e.g. tg3_recycle_rx(),
> tg3_alloc_rx_skb()).  I think we should change them all.

Ok, I'll take care of this.