[UDP]: Defer InDataGrams increment until recvmsg() does checksum

Thanks dave, herbert, gerrit, andi and other people for your
discussion about this problem.

UdpInDatagrams can be confusing because it counts packets that
might be dropped later.
Move UdpInDatagrams into recvmsg() as allowed by the RFC.

Signed-off-by: Wang Chen <wangchen@cn.fujitsu.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/Documentation/networking/udplite.txt b/Documentation/networking/udplite.txt
index b6409cab075ca53aa3a5f4a6276403e0a0463c89..3870f280280b34e6f81cce2229b896357091f7c6 100644 (file)
--- a/Documentation/networking/udplite.txt
+++ b/Documentation/networking/udplite.txt
@@ -236,7 +236,7 @@
 
   This displays UDP-Lite statistics variables, whose meaning is as follows.
 
-   InDatagrams:     Total number of received datagrams.
+   InDatagrams:     The total number of datagrams delivered to users.
 
    NoPorts:         Number of packets received to an unknown port.
                     These cases are counted separately (not as InErrors).

diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c
index 03c400ca14c5af07db1ab22686d95621b5cc8813..3465d4ad301be911a023e68521229e35705c1279 100644 (file)
--- a/net/ipv4/udp.c
+++ b/net/ipv4/udp.c
@@ -873,6 +873,8 @@ try_again:
        if (err)
                goto out_free;
 
+       UDP_INC_STATS_USER(UDP_MIB_INDATAGRAMS, is_udplite);
+
        sock_recv_timestamp(msg, sk, skb);
 
        /* Copy the address. */
@@ -966,10 +968,8 @@ int udp_queue_rcv_skb(struct sock * sk, struct sk_buff *skb)
                        int ret;
 
                        ret = (*up->encap_rcv)(sk, skb);
-                       if (ret <= 0) {
-                               UDP_INC_STATS_BH(UDP_MIB_INDATAGRAMS, up->pcflag);
+                       if (ret <= 0)
                                return -ret;
-                       }
                }
 
                /* FALLTHROUGH -- it's a UDP Packet */
@@ -1023,7 +1023,6 @@ int udp_queue_rcv_skb(struct sock * sk, struct sk_buff *skb)
                goto drop;
        }
 
-       UDP_INC_STATS_BH(UDP_MIB_INDATAGRAMS, up->pcflag);
        return 0;
 
 drop:

diff --git a/net/ipv6/udp.c b/net/ipv6/udp.c
index ee1cc3f8599fd110bca8e77e38e2e9f50b607402..b0474a618bbe6afd8024d19e3c5bf68d7b8ca6fe 100644 (file)
--- a/net/ipv6/udp.c
+++ b/net/ipv6/udp.c
@@ -164,6 +164,8 @@ try_again:
        if (err)
                goto out_free;
 
+       UDP6_INC_STATS_USER(UDP_MIB_INDATAGRAMS, is_udplite);
+
        sock_recv_timestamp(msg, sk, skb);
 
        /* Copy the address. */
@@ -292,7 +294,7 @@ int udpv6_queue_rcv_skb(struct sock * sk, struct sk_buff *skb)
                        UDP6_INC_STATS_BH(UDP_MIB_RCVBUFERRORS, up->pcflag);
                goto drop;
        }
-       UDP6_INC_STATS_BH(UDP_MIB_INDATAGRAMS, up->pcflag);
+
        return 0;
 drop:
        UDP6_INC_STATS_BH(UDP_MIB_INERRORS, up->pcflag);