Commit 4b258461 authored by Krishna Kumar's avatar Krishna Kumar Committed by David S. Miller
Browse files

net: Optimize non-gso test checks 



Avoid checking twice whether skb needs to be linearized, if one
skb_linearize was already done.

Signed-off-by: default avatarKrishna Kumar <krkumar2@in.ibm.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 5f8cbc13

net/core/dev.c

+17 −12
Original line number Diff line number Diff line
@@ -1982,6 +1982,21 @@ static inline int __dev_xmit_skb(struct sk_buff *skb, struct Qdisc *q, 
	return rc;

}



/*

 * Returns true if either:

 *	1. skb has frag_list and the device doesn't support FRAGLIST, or

 *	2. skb is fragmented and the device does not support SG, or if

 *	   at least one of fragments is in highmem and device does not

 *	   support DMA from it.

 */

static inline int skb_needs_linearize(struct sk_buff *skb,

				      struct net_device *dev)

{

	return (skb_has_frags(skb) && !(dev->features & NETIF_F_FRAGLIST)) ||

	       (skb_shinfo(skb)->nr_frags && (!(dev->features & NETIF_F_SG) ||

					      illegal_highdma(dev, skb)));

}



/**

 *	dev_queue_xmit - transmit a buffer

 *	@skb: buffer to transmit
@@ -2018,18 +2033,8 @@ int dev_queue_xmit(struct sk_buff *skb) 
	if (netif_needs_gso(dev, skb))

		goto gso;



	if (skb_has_frags(skb) &&

	    !(dev->features & NETIF_F_FRAGLIST) &&

	    __skb_linearize(skb))

		goto out_kfree_skb;



	/* Fragmented skb is linearized if device does not support SG,

	 * or if at least one of fragments is in highmem and device

	 * does not support DMA from it.

	 */

	if (skb_shinfo(skb)->nr_frags &&

	    (!(dev->features & NETIF_F_SG) || illegal_highdma(dev, skb)) &&

	    __skb_linearize(skb))

	/* Convert a paged skb to linear, if required */

	if (skb_needs_linearize(skb, dev) && __skb_linearize(skb))

		goto out_kfree_skb;



	/* If packet is not checksummed and device does not support