[SCTP]: Extend /proc/net/sctp/snmp to provide more statistics.

This patch adds more statistics info under /proc/net/sctp/snmp
that should be useful for debugging. The additional events that
are counted now include timer expirations, retransmits, packet
and data chunk discards.

The Data chunk discards include all the cases where a data chunk
is discarded including high tsn, bad stream, dup tsn and the most
useful one(out of receive buffer/rwnd).

Also moved the SCTP MIB data structures from the generic include
directories to include/sctp/sctp.h.

Signed-off-by: Sridhar Samudrala <sri@us.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 6 insertions, 2 deletions

diff --git a/net/sctp/input.c b/net/sctp/input.c
index 42b66e74bbb5..8a34d95602ce 100644
--- a/net/sctp/input.c
+++ b/net/sctp/input.c
@@ -255,10 +255,13 @@ int sctp_rcv(struct sk_buff *skb)
          */
         sctp_bh_lock_sock(sk);
 
-        if (sock_owned_by_user(sk))
+        if (sock_owned_by_user(sk)) {
+                SCTP_INC_STATS_BH(SCTP_MIB_IN_PKT_BACKLOG);
                 sctp_add_backlog(sk, skb);
-        else
+        } else {
+                SCTP_INC_STATS_BH(SCTP_MIB_IN_PKT_SOFTIRQ);
                 sctp_inq_push(&chunk->rcvr->inqueue, chunk);
+        }
 
         sctp_bh_unlock_sock(sk);
 
@@ -271,6 +274,7 @@ int sctp_rcv(struct sk_buff *skb)
         return 0;
 
 discard_it:
+        SCTP_INC_STATS_BH(SCTP_MIB_IN_PKT_DISCARDS);
         kfree_skb(skb);
         return 0;