Re: [PATCH 1/6] ehea: interface to network stack

[Jörn Engel]

On Sat, 12 August 2006 06:56:24 +1000, Anton Blanchard wrote:
> 
> > +
> > +				skb_index = ((index - i
> > +					      + port_res->skb_arr_sq_len)
> > +					     % port_res->skb_arr_sq_len);
> 
> This is going to force an expensive divide. Its much better to change
> this to the simpler and quicker:
> 
> i++;
> if (i > max)
> 	i = 0;

Is a conditional cheaper than a divide?  In case of a misprediction I
would assume it to be significantly slower and I don't know the ratio
of mispredictions for this branch.

Jörn

-- 
Victory in war is not repetitious.
-- Sun Tzu
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