[PATCH net-next] skbuff: optimize the pull_pages code in __pskb_pull_tail()

From: Lin Zhang
Date: Thu Jul 06 2017 - 05:02:09 EST


In the pull_pages code block, if the first frags size > eat,
we can end the loop in advance to avoid extra copy.

Signed-off-by: Lin Zhang <xiaolou4617@xxxxxxxxx>
---
net/core/skbuff.c | 4 ++++
1 file changed, 4 insertions(+)

diff --git a/net/core/skbuff.c b/net/core/skbuff.c
index f990eb8..c00a1df 100644
--- a/net/core/skbuff.c
+++ b/net/core/skbuff.c
@@ -1720,6 +1720,10 @@ void *__pskb_pull_tail(struct sk_buff *skb, int delta)
skb_shinfo(skb)->frags[k].page_offset += eat;
skb_frag_size_sub(&skb_shinfo(skb)->frags[k], eat);
eat = 0;
+ if (!i) {
+ k = skb_shinfo(skb)->nr_frags;
+ break;
+ }
}
k++;
}
--
1.8.3.1