diff options
| author | Eric Dumazet <edumazet@google.com> | 2016-12-07 21:05:36 +0300 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2016-12-08 21:30:22 +0300 |
| commit | 3665f3817cd354ab7a811b3a4f282c4f5cb1a0d0 (patch) | |
| tree | bfa286eca8f2807aa35c241507e05955884379b2 | |
| parent | c8c8b127091b758f5768f906bcdeeb88bc9951ca (diff) | |
| download | linux-3665f3817cd354ab7a811b3a4f282c4f5cb1a0d0.tar.xz | |
net: do not read sk_drops if application does not care
sk_drops can be an often written field, do not read it unless
application showed interest.
Note that sk_drops can be read via inet_diag, so applications
can avoid getting this info from every received packet.
In the future, 'reading' sk_drops might require folding per node or per
cpu fields, and thus become even more expensive than today.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
| -rw-r--r-- | include/net/sock.h | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/include/net/sock.h b/include/net/sock.h index 2729e77950b7..e17aa3de2b4d 100644 --- a/include/net/sock.h +++ b/include/net/sock.h @@ -2163,7 +2163,8 @@ struct sock_skb_cb { static inline void sock_skb_set_dropcount(const struct sock *sk, struct sk_buff *skb) { - SOCK_SKB_CB(skb)->dropcount = atomic_read(&sk->sk_drops); + SOCK_SKB_CB(skb)->dropcount = sock_flag(sk, SOCK_RXQ_OVFL) ? + atomic_read(&sk->sk_drops) : 0; } static inline void sk_drops_add(struct sock *sk, const struct sk_buff *skb) |