diff options
| author | Ilpo Järvinen <ilpo.jarvinen@helsinki.fi> | 2007-08-24 22:55:52 -0700 |
|---|---|---|
| committer | David S. Miller <davem@sunset.davemloft.net> | 2007-10-10 16:48:30 -0700 |
| commit | 18f02545a9a16c9a89778b91a162ad16d510bb32 (patch) | |
| tree | 2b1c67a8168b695630d26216b7dd3be17179ca5c /net | |
| parent | 5b3c98821a8753239aefc1c217409aa3e5c90787 (diff) | |
[TCP] MIB: Add counters for discarded SACK blocks
In DSACK case, some events are not extraordinary, such as packet
duplication generated DSACK. They can arrive easily below
snd_una when undo_marker is not set (TCP being in CA_Open),
counting such DSACKs amoung SACK discards will likely just
mislead if they occur in some scenario when there are other
problems as well. Similarly, excessively delayed packets could
cause "normal" DSACKs. Therefore, separate counters are
allocated for DSACK events.
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net')
| -rw-r--r-- | net/ipv4/proc.c | 3 | ||||
| -rw-r--r-- | net/ipv4/tcp_input.c | 10 |
2 files changed, 12 insertions, 1 deletions
diff --git a/net/ipv4/proc.c b/net/ipv4/proc.c index 3b690cf2a4e..986d1c83a00 100644 --- a/net/ipv4/proc.c +++ b/net/ipv4/proc.c @@ -244,6 +244,9 @@ static const struct snmp_mib snmp4_net_list[] = { SNMP_MIB_ITEM("TCPAbortOnLinger", LINUX_MIB_TCPABORTONLINGER), SNMP_MIB_ITEM("TCPAbortFailed", LINUX_MIB_TCPABORTFAILED), SNMP_MIB_ITEM("TCPMemoryPressures", LINUX_MIB_TCPMEMORYPRESSURES), + SNMP_MIB_ITEM("TCPSACKDiscard", LINUX_MIB_TCPSACKDISCARD), + SNMP_MIB_ITEM("TCPDSACKIgnoredOld", LINUX_MIB_TCPDSACKIGNOREDOLD), + SNMP_MIB_ITEM("TCPDSACKIgnoredNoUndo", LINUX_MIB_TCPDSACKIGNOREDNOUNDO), SNMP_MIB_SENTINEL }; diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c index a2364ebf858..f9e4d7ad68b 100644 --- a/net/ipv4/tcp_input.c +++ b/net/ipv4/tcp_input.c @@ -1240,8 +1240,16 @@ tcp_sacktag_write_queue(struct sock *sk, struct sk_buff *ack_skb, u32 prior_snd_ int fack_count; int dup_sack = (found_dup_sack && (i == first_sack_index)); - if (!tcp_is_sackblock_valid(tp, dup_sack, start_seq, end_seq)) + if (!tcp_is_sackblock_valid(tp, dup_sack, start_seq, end_seq)) { + if (dup_sack) { + if (!tp->undo_marker) + NET_INC_STATS_BH(LINUX_MIB_TCPDSACKIGNOREDNOUNDO); + else + NET_INC_STATS_BH(LINUX_MIB_TCPDSACKIGNOREDOLD); + } else + NET_INC_STATS_BH(LINUX_MIB_TCPSACKDISCARD); continue; + } skb = cached_skb; fack_count = cached_fack_count; |