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authorYuchung Cheng <ycheng@google.com>2018-11-28 16:06:45 -0800
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2019-12-13 08:52:20 +0100
commit01775a8dc616d465cfb28ee1b928803179bec440 (patch)
tree744caadb9e9b9d6fdc3b6d8c5fc56bcf486b1da0 /net
parenta5f37a687f3fc7c3cea674287642424ebf9764a1 (diff)
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tcp: fix SNMP TCP timeout under-estimation
[ 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>
Diffstat (limited to 'net')
-rw-r--r--net/ipv4/tcp_timer.c8
1 files changed, 4 insertions, 4 deletions
diff --git a/net/ipv4/tcp_timer.c b/net/ipv4/tcp_timer.c
index 50b15e1c633b..681882a40968 100644
--- a/net/ipv4/tcp_timer.c
+++ b/net/ipv4/tcp_timer.c
@@ -482,11 +482,12 @@ 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))
@@ -501,10 +502,9 @@ 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);