From: Yuchung Cheng ycheng@google.com
[ Upstream commit e1561fe2dd69dc5dddd69bd73aa65355bdfb048b ]
Previously the SNMP TCPTIMEOUTS counter has inconsistent accounting: 1. It counts all SYN and SYN-ACK timeouts 2. It counts timeouts in other states except recurring timeouts and timeouts after fast recovery or disorder state.
Such selective accounting makes analysis difficult and complicated. For example the monitoring system needs to collect many other SNMP counters to infer the total amount of timeout events. This patch makes TCPTIMEOUTS counter simply counts all the retransmit timeout (SYN or data or FIN).
Signed-off-by: Yuchung Cheng ycheng@google.com Signed-off-by: Eric Dumazet edumazet@google.com Signed-off-by: Neal Cardwell ncardwell@google.com Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Sasha Levin sashal@kernel.org --- net/ipv4/tcp_timer.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-)
diff --git a/net/ipv4/tcp_timer.c b/net/ipv4/tcp_timer.c index ad0083f7b5dd3..761a198ed5f30 100644 --- a/net/ipv4/tcp_timer.c +++ b/net/ipv4/tcp_timer.c @@ -478,11 +478,12 @@ void tcp_retransmit_timer(struct sock *sk) goto out_reset_timer; }
+ __NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPTIMEOUTS); if (tcp_write_timeout(sk)) goto out;
if (icsk->icsk_retransmits == 0) { - int mib_idx; + int mib_idx = 0;
if (icsk->icsk_ca_state == TCP_CA_Recovery) { if (tcp_is_sack(tp)) @@ -497,10 +498,9 @@ void tcp_retransmit_timer(struct sock *sk) mib_idx = LINUX_MIB_TCPSACKFAILURES; else mib_idx = LINUX_MIB_TCPRENOFAILURES; - } else { - mib_idx = LINUX_MIB_TCPTIMEOUTS; } - __NET_INC_STATS(sock_net(sk), mib_idx); + if (mib_idx) + __NET_INC_STATS(sock_net(sk), mib_idx); }
tcp_enter_loss(sk);