ip_frag: Remove some atomic ops

Instead of doing one atomic operation per frag, we can factorize them.

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 1 insertions, 2 deletions

diff --git a/net/ipv4/ip_fragment.c b/net/ipv4/ip_fragment.c
index 75347ea70ea0..963c3689d0af 100644
--- a/net/ipv4/ip_fragment.c
+++ b/net/ipv4/ip_fragment.c
@@ -556,7 +556,6 @@ static int ip_frag_reasm(struct ipq *qp, struct sk_buff *prev,
 
         skb_shinfo(head)->frag_list = head->next;
         skb_push(head, head->data - skb_network_header(head));
-        atomic_sub(head->truesize, &qp->q.net->mem);
 
         for (fp=head->next; fp; fp = fp->next) {
                 head->data_len += fp->len;
@@ -566,8 +565,8 @@ static int ip_frag_reasm(struct ipq *qp, struct sk_buff *prev,
                 else if (head->ip_summed == CHECKSUM_COMPLETE)
                         head->csum = csum_add(head->csum, fp->csum);
                 head->truesize += fp->truesize;
-                atomic_sub(fp->truesize, &qp->q.net->mem);
         }
+        atomic_sub(head->truesize, &qp->q.net->mem);
 
         head->next = NULL;
         head->dev = dev;