Commit 1ddc3229 authored by Yunsheng Lin's avatar Yunsheng Lin Committed by David S. Miller
Browse files

skbuff: remove some unnecessary operation in skb_segment_list() 



gro list uses skb_shinfo(skb)->frag_list to link two skb together,
and NAPI_GRO_CB(p)->last->next is used when there are more skb,
see skb_gro_receive_list(). gso expects that each segmented skb is
linked together using skb->next, so only the first skb->next need
to set to skb_shinfo(skb)-> frag_list when doing gso list segment.

It is the same reason that nskb->next does not need to be set to
list_skb before goto the error handling, because nskb->next already
pointers to list_skb.

And nskb is also the last skb at the end of loop, so remove tail
variable and use nskb instead.

Signed-off-by: default avatarYunsheng Lin <linyunsheng@huawei.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 134639e9

net/core/skbuff.c

+3 −12
Original line number Diff line number Diff line
@@ -3732,13 +3732,13 @@ struct sk_buff *skb_segment_list(struct sk_buff *skb, 
	unsigned int tnl_hlen = skb_tnl_header_len(skb);

	unsigned int delta_truesize = 0;

	unsigned int delta_len = 0;

	struct sk_buff *tail = NULL;

	struct sk_buff *nskb, *tmp;

	int err;



	skb_push(skb, -skb_network_offset(skb) + offset);



	skb_shinfo(skb)->frag_list = NULL;

	skb->next = list_skb;



	do {

		nskb = list_skb;
@@ -3756,17 +3756,8 @@ struct sk_buff *skb_segment_list(struct sk_buff *skb, 
			}

		}



		if (!tail)

			skb->next = nskb;

		else

			tail->next = nskb;



		if (unlikely(err)) {

			nskb->next = list_skb;

		if (unlikely(err))

			goto err_linearize;

		}



		tail = nskb;



		delta_len += nskb->len;

		delta_truesize += nskb->truesize;
@@ -3793,7 +3784,7 @@ struct sk_buff *skb_segment_list(struct sk_buff *skb, 


	skb_gso_reset(skb);



	skb->prev = tail;

	skb->prev = nskb;



	if (skb_needs_linearize(skb, features) &&

	    __skb_linearize(skb))