[PATCH v1 net] net: use skb_clone to avoid alloc_pages failure.

[PATCH v1 net] net: use skb_clone to avoid alloc_pages failure.

[martinbj2008]

From: Martin Zhang <martinbj2008@gmail.com>

1. new skb only need dst and ip address(v4 or v6).
2. skb_copy may need high order pages, which is very rare on long running server.

Signed-off-by: Junwei Zhang <linggao.zjw@alibaba-inc.com>
Signed-off-by: Martin Zhang <martinbj2008@gmail.com>
---

 net/core/neighbour.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/net/core/neighbour.c b/net/core/neighbour.c
index 1aa8437..e6af42d 100644
--- a/net/core/neighbour.c
+++ b/net/core/neighbour.c
@@ -857,7 +857,7 @@ static void neigh_probe(struct neighbour *neigh)
 	struct sk_buff *skb = skb_peek_tail(&neigh->arp_queue);
 	/* keep skb alive even if arp_queue overflows */
 	if (skb)
-		skb = skb_copy(skb, GFP_ATOMIC);
+		skb = skb_clone(skb, GFP_ATOMIC);
 	write_unlock(&neigh->lock);
 	neigh->ops->solicit(neigh, skb);
 	atomic_inc(&neigh->probes);
-- 
2.1.4

Re: [PATCH v1 net] net: use skb_clone to avoid alloc_pages failure.

[Eric Dumazet]

On Tue, 2015-11-17 at 20:49 +0800, martinbj2008@gmail.com wrote:
> From: Martin Zhang <martinbj2008@gmail.com>
> 
> 1. new skb only need dst and ip address(v4 or v6).
> 2. skb_copy may need high order pages, which is very rare on long running server.
> 
> Signed-off-by: Junwei Zhang <linggao.zjw@alibaba-inc.com>
> Signed-off-by: Martin Zhang <martinbj2008@gmail.com>
> ---

Acked-by: Eric Dumazet <edumazet@google.com>

Re: [PATCH v1 net] net: use skb_clone to avoid alloc_pages failure.

[Eric Dumazet]

On Tue, 2015-11-17 at 05:07 -0800, Eric Dumazet wrote:
> On Tue, 2015-11-17 at 20:49 +0800, martinbj2008@gmail.com wrote:
> > From: Martin Zhang <martinbj2008@gmail.com>
> > 
> > 1. new skb only need dst and ip address(v4 or v6).
> > 2. skb_copy may need high order pages, which is very rare on long running server.
> > 
> > Signed-off-by: Junwei Zhang <linggao.zjw@alibaba-inc.com>
> > Signed-off-by: Martin Zhang <martinbj2008@gmail.com>
> > ---
> 
> Acked-by: Eric Dumazet <edumazet@google.com>
> 

BTW, very nice catch, thanks guys !

Re: [PATCH v1 net] net: use skb_clone to avoid alloc_pages failure.

[David Miller]

From: martinbj2008@gmail.com
Date: Tue, 17 Nov 2015 20:49:30 +0800

> From: Martin Zhang <martinbj2008@gmail.com>
> 
> 1. new skb only need dst and ip address(v4 or v6).
> 2. skb_copy may need high order pages, which is very rare on long running server.
> 
> Signed-off-by: Junwei Zhang <linggao.zjw@alibaba-inc.com>
> Signed-off-by: Martin Zhang <martinbj2008@gmail.com>

Applied, thanks.