Message ID | 1335528603.2775.246.camel@edumazet-glaptop |
---|---|
State | Accepted, archived |
Delegated to: | David Miller |
Headers | show |
From: Eric Dumazet <eric.dumazet@gmail.com> Date: Fri, 27 Apr 2012 14:10:03 +0200 > From: Eric Dumazet <edumazet@google.com> > > __skb_splice_bits() can check if skb to be spliced has its skb->head > mapped to a page fragment, instead of a kmalloc() area. > > If so we can avoid a copy of the skb head and get a reference on > underlying page. > > Signed-off-by: Eric Dumazet <edumazet@google.com> Applied. -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/net/core/skbuff.c b/net/core/skbuff.c index 2ad1ee7..e5bd086 100644 --- a/net/core/skbuff.c +++ b/net/core/skbuff.c @@ -1699,14 +1699,18 @@ static bool __skb_splice_bits(struct sk_buff *skb, struct pipe_inode_info *pipe, struct splice_pipe_desc *spd, struct sock *sk) { int seg; + bool head_is_linear = !skb->head_frag; - /* - * map the linear part + /* map the linear part : + * If skb->head_frag is set, this 'linear' part is backed + * by a fragment, and we can avoid a copy. */ if (__splice_segment(virt_to_page(skb->data), (unsigned long) skb->data & (PAGE_SIZE - 1), skb_headlen(skb), - offset, len, skb, spd, true, sk, pipe)) + offset, len, skb, spd, + head_is_linear, + sk, pipe)) return true; /*