From eaa72dc47488d599439cd0fd0f8c4f1bcb3906bb Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Tue, 29 Aug 2017 15:16:01 -0700 Subject: neigh: increase queue_len_bytes to match wmem_default Florian reported UDP xmit drops that could be root caused to the too small neigh limit. Current limit is 64 KB, meaning that even a single UDP socket would hit it, since its default sk_sndbuf comes from net.core.wmem_default (~212992 bytes on 64bit arches). Once ARP/ND resolution is in progress, we should allow a little more packets to be queued, at least for one producer. Once neigh arp_queue is filled, a rogue socket should hit its sk_sndbuf limit and either block in sendmsg() or return -EAGAIN. Signed-off-by: Eric Dumazet Reported-by: Florian Fainelli Signed-off-by: David S. Miller --- include/net/sock.h | 10 ++++++++++ 1 file changed, 10 insertions(+) (limited to 'include/net') diff --git a/include/net/sock.h b/include/net/sock.h index 1c2912d433e8..03a362568357 100644 --- a/include/net/sock.h +++ b/include/net/sock.h @@ -2368,6 +2368,16 @@ bool sk_net_capable(const struct sock *sk, int cap); void sk_get_meminfo(const struct sock *sk, u32 *meminfo); +/* Take into consideration the size of the struct sk_buff overhead in the + * determination of these values, since that is non-constant across + * platforms. This makes socket queueing behavior and performance + * not depend upon such differences. + */ +#define _SK_MEM_PACKETS 256 +#define _SK_MEM_OVERHEAD SKB_TRUESIZE(256) +#define SK_WMEM_MAX (_SK_MEM_OVERHEAD * _SK_MEM_PACKETS) +#define SK_RMEM_MAX (_SK_MEM_OVERHEAD * _SK_MEM_PACKETS) + extern __u32 sysctl_wmem_max; extern __u32 sysctl_rmem_max; -- cgit v1.3-14-g43fede