From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: [PATCH 3/3] NET: [CORE] Stack changes to add multiqueue
 hardware support API
Date: Mon, 18 Jun 2007 23:28:43 -0700 (PDT)
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From: PJ Waskiewicz <peter.p.waskiewicz.jr@intel.com>
Date: Mon, 18 Jun 2007 11:42:29 -0700

> +
> + 	/* The TX queue control structures */
> + 	struct net_device_subqueue	*egress_subqueue;
> + 	int				egress_subqueue_count;

Since every net device will have at least one subqueue, I
would suggest that you do this as follows:

1) In net_device change the quoted part of the patch above to:

	int				egress_subqueue_count;
	struct net_device_subqueue	egress_subqueue[0];

2) In alloc_netdev():

   Factor (sizeof(struct egress_subqueue) * num_subqueues) into
   the net_device allocation size, place the "priv" area after
   the subqueues.

This will save us pointer dereferences on all of these quite
common accesses.