| Message ID | 1285345177.2503.346.camel@edumazet-laptop |
|---|---|
| State | Accepted, archived |
| Delegated to: | David Miller |
| Headers | show |
From: Eric Dumazet <eric.dumazet@gmail.com> Date: Fri, 24 Sep 2010 18:19:37 +0200 > SOCK_MIN_RCVBUF current value is 256 bytes > > It doesnt permit to receive the smallest possible frame, considering > socket sk_rmem_alloc/sk_rcvbuf account skb truesizes. On 64bit arches, > sizeof(struct sk_buff) is 240 bytes. Add the typical 64 bytes of > headroom, and we go over the limit. > > With old kernels and 32bit arches, we were under the limit, if netdriver > was doing copybreak. > > Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Fair enough, applied, thanks Eric. -- 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/include/net/sock.h b/include/net/sock.h index 8ae97c4..c33e62c 100644 --- a/include/net/sock.h +++ b/include/net/sock.h @@ -1558,7 +1558,11 @@ static inline void sk_wake_async(struct sock *sk, int how, int band) } #define SOCK_MIN_SNDBUF 2048 -#define SOCK_MIN_RCVBUF 256 +/* + * Since sk_rmem_alloc sums skb->truesize, even a small frame might need + * sizeof(sk_buff) + MTU + padding, unless net driver perform copybreak + */ +#define SOCK_MIN_RCVBUF (2048 + sizeof(struct sk_buff)) static inline void sk_stream_moderate_sndbuf(struct sock *sk) {
SOCK_MIN_RCVBUF current value is 256 bytes It doesnt permit to receive the smallest possible frame, considering socket sk_rmem_alloc/sk_rcvbuf account skb truesizes. On 64bit arches, sizeof(struct sk_buff) is 240 bytes. Add the typical 64 bytes of headroom, and we go over the limit. With old kernels and 32bit arches, we were under the limit, if netdriver was doing copybreak. Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> --- include/net/sock.h | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) -- 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