sctp: Add support to per-association statistics via a new SCTP_GET_ASSOC_STATS call
The current SCTP stack is lacking a mechanism to have per association
statistics. This is an implementation modeled after OpenSolaris'
SCTP_GET_ASSOC_STATS.
Userspace part will follow on lksctp if/when there is a general ACK on
this.
V4:
- Move ipackets++ before q->immediate.func() for consistency reasons
- Move sctp_max_rto() at the end of sctp_transport_update_rto() to avoid
returning bogus RTO values
- return asoc->rto_min when max_obs_rto value has not changed
V3:
- Increase ictrlchunks in sctp_assoc_bh_rcv() as well
- Move ipackets++ to sctp_inq_push()
- return 0 when no rto updates took place since the last call
V2:
- Implement partial retrieval of stat struct to cope for future expansion
- Kill the rtxpackets counter as it cannot be precise anyway
- Rename outseqtsns to outofseqtsns to make it clearer that these are out
of sequence unexpected TSNs
- Move asoc->ipackets++ under a lock to avoid potential miscounts
- Fold asoc->opackets++ into the already existing asoc check
- Kill unneeded (q->asoc) test when increasing rtxchunks
- Do not count octrlchunks if sending failed (SCTP_XMIT_OK != 0)
- Don't count SHUTDOWNs as SACKs
- Move SCTP_GET_ASSOC_STATS to the private space API
- Adjust the len check in sctp_getsockopt_assoc_stats() to allow for
future struct growth
- Move association statistics in their own struct
- Update idupchunks when we send a SACK with dup TSNs
- return min_rto in max_rto when RTO has not changed. Also return the
transport when max_rto last changed.
Signed-off: Michele Baldessari <michele@acksyn.org>
Acked-by: Vlad Yasevich <vyasevich@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/sctp/socket.c b/net/sctp/socket.c
index bc16249..9e65758 100644
--- a/net/sctp/socket.c
+++ b/net/sctp/socket.c
@@ -611,6 +611,7 @@
2*asoc->pathmtu, 4380));
trans->ssthresh = asoc->peer.i.a_rwnd;
trans->rto = asoc->rto_initial;
+ sctp_max_rto(asoc, trans);
trans->rtt = trans->srtt = trans->rttvar = 0;
sctp_transport_route(trans, NULL,
sctp_sk(asoc->base.sk));
@@ -5635,6 +5636,71 @@
return 0;
}
+/*
+ * SCTP_GET_ASSOC_STATS
+ *
+ * This option retrieves local per endpoint statistics. It is modeled
+ * after OpenSolaris' implementation
+ */
+static int sctp_getsockopt_assoc_stats(struct sock *sk, int len,
+ char __user *optval,
+ int __user *optlen)
+{
+ struct sctp_assoc_stats sas;
+ struct sctp_association *asoc = NULL;
+
+ /* User must provide at least the assoc id */
+ if (len < sizeof(sctp_assoc_t))
+ return -EINVAL;
+
+ if (copy_from_user(&sas, optval, len))
+ return -EFAULT;
+
+ asoc = sctp_id2assoc(sk, sas.sas_assoc_id);
+ if (!asoc)
+ return -EINVAL;
+
+ sas.sas_rtxchunks = asoc->stats.rtxchunks;
+ sas.sas_gapcnt = asoc->stats.gapcnt;
+ sas.sas_outofseqtsns = asoc->stats.outofseqtsns;
+ sas.sas_osacks = asoc->stats.osacks;
+ sas.sas_isacks = asoc->stats.isacks;
+ sas.sas_octrlchunks = asoc->stats.octrlchunks;
+ sas.sas_ictrlchunks = asoc->stats.ictrlchunks;
+ sas.sas_oodchunks = asoc->stats.oodchunks;
+ sas.sas_iodchunks = asoc->stats.iodchunks;
+ sas.sas_ouodchunks = asoc->stats.ouodchunks;
+ sas.sas_iuodchunks = asoc->stats.iuodchunks;
+ sas.sas_idupchunks = asoc->stats.idupchunks;
+ sas.sas_opackets = asoc->stats.opackets;
+ sas.sas_ipackets = asoc->stats.ipackets;
+
+ /* New high max rto observed, will return 0 if not a single
+ * RTO update took place. obs_rto_ipaddr will be bogus
+ * in such a case
+ */
+ sas.sas_maxrto = asoc->stats.max_obs_rto;
+ memcpy(&sas.sas_obs_rto_ipaddr, &asoc->stats.obs_rto_ipaddr,
+ sizeof(struct sockaddr_storage));
+
+ /* Mark beginning of a new observation period */
+ asoc->stats.max_obs_rto = asoc->rto_min;
+
+ /* Allow the struct to grow and fill in as much as possible */
+ len = min_t(size_t, len, sizeof(sas));
+
+ if (put_user(len, optlen))
+ return -EFAULT;
+
+ SCTP_DEBUG_PRINTK("sctp_getsockopt_assoc_stat(%d): %d\n",
+ len, sas.sas_assoc_id);
+
+ if (copy_to_user(optval, &sas, len))
+ return -EFAULT;
+
+ return 0;
+}
+
SCTP_STATIC int sctp_getsockopt(struct sock *sk, int level, int optname,
char __user *optval, int __user *optlen)
{
@@ -5776,6 +5842,9 @@
case SCTP_PEER_ADDR_THLDS:
retval = sctp_getsockopt_paddr_thresholds(sk, optval, len, optlen);
break;
+ case SCTP_GET_ASSOC_STATS:
+ retval = sctp_getsockopt_assoc_stats(sk, len, optval, optlen);
+ break;
default:
retval = -ENOPROTOOPT;
break;
