nagai/kernel
3
0
Fork 0
forked from mirrors/linux
Code Pull requests Activity

skbuff: remove some unnecessary operation in skb_segment_list()

Browse source 
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: Yunsheng Lin <linyunsheng@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Yunsheng Lin 2021-03-10 16:28:58 +08:00 committed by David S. Miller
parent 134639e9cc
commit 1ddc3229ad
1 changed files with 3 additions and 12 deletions
repo.diff.show_diff_stats Download patch file Download diff file Expand all files Collapse all files

15
net/core/skbuff.c
View file

@ -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 tnl_hlen = skb_tnl_header_len(skb);
unsigned int delta_truesize = 0; unsigned int delta_truesize = 0;
unsigned int delta_len = 0; unsigned int delta_len = 0;
struct sk_buff *tail = NULL;
struct sk_buff *nskb, *tmp; struct sk_buff *nskb, *tmp;
int err; int err;
skb_push(skb, -skb_network_offset(skb) + offset); skb_push(skb, -skb_network_offset(skb) + offset);
skb_shinfo(skb)->frag_list = NULL; skb_shinfo(skb)->frag_list = NULL;
skb->next = list_skb;
do { do {
nskb = list_skb; nskb = list_skb;
@ -3756,17 +3756,8 @@ struct sk_buff *skb_segment_list(struct sk_buff *skb,
} }
} }
if (!tail) if (unlikely(err))
skb->next = nskb;
else
tail->next = nskb;
if (unlikely(err)) {
nskb->next = list_skb;
goto err_linearize; goto err_linearize;
}
tail = nskb;
delta_len += nskb->len; delta_len += nskb->len;
delta_truesize += nskb->truesize; delta_truesize += nskb->truesize;
@ -3793,7 +3784,7 @@ struct sk_buff *skb_segment_list(struct sk_buff *skb,
skb_gso_reset(skb); skb_gso_reset(skb);
skb->prev = tail; skb->prev = nskb;
if (skb_needs_linearize(skb, features) && if (skb_needs_linearize(skb, features) &&
__skb_linearize(skb)) __skb_linearize(skb))