diff options
| author | Eric Dumazet <edumazet@google.com> | 2025-01-13 13:55:58 +0000 |
|---|---|---|
| committer | Jakub Kicinski <kuba@kernel.org> | 2025-01-14 13:28:13 -0800 |
| commit | d16b34479064fcb8dbb66a72308b5034be819161 (patch) | |
| tree | 5fd02d2298c5cd5c174f0f8775e5673fdaa654d3 | |
| parent | 124c4c32e9f3b4d89f5be3342897adc8db5c27b8 (diff) | |
tcp: add LINUX_MIB_PAWS_OLD_ACK SNMP counter
Prior patch in the series added TCP_RFC7323_PAWS_ACK drop reason.
This patch adds the corresponding SNMP counter, for folks
using nstat instead of tracing for TCP diagnostics.
nstat -az | grep PAWSOldAck
Suggested-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Neal Cardwell <ncardwell@google.com>
Reviewed-by: Jason Xing <kerneljasonxing@gmail.com>
Tested-by: Neal Cardwell <ncardwell@google.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Link: https://patch.msgid.link/20250113135558.3180360-4-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
| -rw-r--r-- | include/net/dropreason-core.h | 1 | ||||
| -rw-r--r-- | include/uapi/linux/snmp.h | 1 | ||||
| -rw-r--r-- | net/ipv4/proc.c | 1 | ||||
| -rw-r--r-- | net/ipv4/tcp_input.c | 7 |
4 files changed, 7 insertions, 3 deletions
diff --git a/include/net/dropreason-core.h b/include/net/dropreason-core.h index 28555109f9bd..ed864934e20b 100644 --- a/include/net/dropreason-core.h +++ b/include/net/dropreason-core.h @@ -262,6 +262,7 @@ enum skb_drop_reason { SKB_DROP_REASON_TCP_RFC7323_PAWS, /** * @SKB_DROP_REASON_TCP_RFC7323_PAWS_ACK: PAWS check, old ACK packet. + * Corresponds to LINUX_MIB_PAWS_OLD_ACK. */ SKB_DROP_REASON_TCP_RFC7323_PAWS_ACK, /** @SKB_DROP_REASON_TCP_OLD_SEQUENCE: Old SEQ field (duplicate packet) */ diff --git a/include/uapi/linux/snmp.h b/include/uapi/linux/snmp.h index 2e75674e7d4f..848c7784e684 100644 --- a/include/uapi/linux/snmp.h +++ b/include/uapi/linux/snmp.h @@ -186,6 +186,7 @@ enum LINUX_MIB_TIMEWAITKILLED, /* TimeWaitKilled */ LINUX_MIB_PAWSACTIVEREJECTED, /* PAWSActiveRejected */ LINUX_MIB_PAWSESTABREJECTED, /* PAWSEstabRejected */ + LINUX_MIB_PAWS_OLD_ACK, /* PAWSOldAck */ LINUX_MIB_DELAYEDACKS, /* DelayedACKs */ LINUX_MIB_DELAYEDACKLOCKED, /* DelayedACKLocked */ LINUX_MIB_DELAYEDACKLOST, /* DelayedACKLost */ diff --git a/net/ipv4/proc.c b/net/ipv4/proc.c index 40053a02bae1..affd21a0f572 100644 --- a/net/ipv4/proc.c +++ b/net/ipv4/proc.c @@ -189,6 +189,7 @@ static const struct snmp_mib snmp4_net_list[] = { SNMP_MIB_ITEM("TWKilled", LINUX_MIB_TIMEWAITKILLED), SNMP_MIB_ITEM("PAWSActive", LINUX_MIB_PAWSACTIVEREJECTED), SNMP_MIB_ITEM("PAWSEstab", LINUX_MIB_PAWSESTABREJECTED), + SNMP_MIB_ITEM("PAWSOldAck", LINUX_MIB_PAWS_OLD_ACK), SNMP_MIB_ITEM("DelayedACKs", LINUX_MIB_DELAYEDACKS), SNMP_MIB_ITEM("DelayedACKLocked", LINUX_MIB_DELAYEDACKLOCKED), SNMP_MIB_ITEM("DelayedACKLost", LINUX_MIB_DELAYEDACKLOST), diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c index dc0e88bcc535..eb82e01da911 100644 --- a/net/ipv4/tcp_input.c +++ b/net/ipv4/tcp_input.c @@ -5969,12 +5969,13 @@ static bool tcp_validate_incoming(struct sock *sk, struct sk_buff *skb, if (unlikely(th->syn)) goto syn_challenge; - /* Old ACK are common, do not change PAWSESTABREJECTED + /* Old ACK are common, increment PAWS_OLD_ACK * and do not send a dupack. */ - if (reason == SKB_DROP_REASON_TCP_RFC7323_PAWS_ACK) + if (reason == SKB_DROP_REASON_TCP_RFC7323_PAWS_ACK) { + NET_INC_STATS(sock_net(sk), LINUX_MIB_PAWS_OLD_ACK); goto discard; - + } NET_INC_STATS(sock_net(sk), LINUX_MIB_PAWSESTABREJECTED); if (!tcp_oow_rate_limited(sock_net(sk), skb, LINUX_MIB_TCPACKSKIPPEDPAWS, |