From a6df1ae9383697c4eb1365176002f154982325ad Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Mon, 16 Jul 2012 01:41:36 +0000 Subject: [PATCH] tcp: add OFO snmp counters Add three SNMP TCP counters, to better track TCP behavior at global stage (netstat -s), when packets are received Out Of Order (OFO) TCPOFOQueue : Number of packets queued in OFO queue TCPOFODrop : Number of packets meant to be queued in OFO but dropped because socket rcvbuf limit hit. TCPOFOMerge : Number of packets in OFO that were merged with other packets. Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller --- include/linux/snmp.h | 5 ++++- net/ipv4/proc.c | 3 +++ net/ipv4/tcp_input.c | 7 +++++-- 3 files changed, 12 insertions(+), 3 deletions(-) diff --git a/include/linux/snmp.h b/include/linux/snmp.h index 2e68f5ba0389..6e4c51123828 100644 --- a/include/linux/snmp.h +++ b/include/linux/snmp.h @@ -233,7 +233,10 @@ enum LINUX_MIB_TCPREQQFULLDOCOOKIES, /* TCPReqQFullDoCookies */ LINUX_MIB_TCPREQQFULLDROP, /* TCPReqQFullDrop */ LINUX_MIB_TCPRETRANSFAIL, /* TCPRetransFail */ - LINUX_MIB_TCPRCVCOALESCE, /* TCPRcvCoalesce */ + LINUX_MIB_TCPRCVCOALESCE, /* TCPRcvCoalesce */ + LINUX_MIB_TCPOFOQUEUE, /* TCPOFOQueue */ + LINUX_MIB_TCPOFODROP, /* TCPOFODrop */ + LINUX_MIB_TCPOFOMERGE, /* TCPOFOMerge */ __LINUX_MIB_MAX }; diff --git a/net/ipv4/proc.c b/net/ipv4/proc.c index 8af0d44e4e22..dae25e7622cf 100644 --- a/net/ipv4/proc.c +++ b/net/ipv4/proc.c @@ -258,6 +258,9 @@ static const struct snmp_mib snmp4_net_list[] = { SNMP_MIB_ITEM("TCPReqQFullDrop", LINUX_MIB_TCPREQQFULLDROP), SNMP_MIB_ITEM("TCPRetransFail", LINUX_MIB_TCPRETRANSFAIL), SNMP_MIB_ITEM("TCPRcvCoalesce", LINUX_MIB_TCPRCVCOALESCE), + SNMP_MIB_ITEM("TCPOFOQueue", LINUX_MIB_TCPOFOQUEUE), + SNMP_MIB_ITEM("TCPOFODrop", LINUX_MIB_TCPOFODROP), + SNMP_MIB_ITEM("TCPOFOMerge", LINUX_MIB_TCPOFOMERGE), SNMP_MIB_SENTINEL }; diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c index 055ac49b8b40..cc4e12f1f2f7 100644 --- a/net/ipv4/tcp_input.c +++ b/net/ipv4/tcp_input.c @@ -4397,8 +4397,8 @@ static void tcp_data_queue_ofo(struct sock *sk, struct sk_buff *skb) TCP_ECN_check_ce(tp, skb); - if (tcp_try_rmem_schedule(sk, skb->truesize)) { - /* TODO: should increment a counter */ + if (unlikely(tcp_try_rmem_schedule(sk, skb->truesize))) { + NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_TCPOFODROP); __kfree_skb(skb); return; } @@ -4407,6 +4407,7 @@ static void tcp_data_queue_ofo(struct sock *sk, struct sk_buff *skb) tp->pred_flags = 0; inet_csk_schedule_ack(sk); + NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_TCPOFOQUEUE); SOCK_DEBUG(sk, "out of order segment: rcv_next %X seq %X - %X\n", tp->rcv_nxt, TCP_SKB_CB(skb)->seq, TCP_SKB_CB(skb)->end_seq); @@ -4460,6 +4461,7 @@ static void tcp_data_queue_ofo(struct sock *sk, struct sk_buff *skb) if (skb1 && before(seq, TCP_SKB_CB(skb1)->end_seq)) { if (!after(end_seq, TCP_SKB_CB(skb1)->end_seq)) { /* All the bits are present. Drop. */ + NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_TCPOFOMERGE); __kfree_skb(skb); skb = NULL; tcp_dsack_set(sk, seq, end_seq); @@ -4498,6 +4500,7 @@ static void tcp_data_queue_ofo(struct sock *sk, struct sk_buff *skb) __skb_unlink(skb1, &tp->out_of_order_queue); tcp_dsack_extend(sk, TCP_SKB_CB(skb1)->seq, TCP_SKB_CB(skb1)->end_seq); + NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_TCPOFOMERGE); __kfree_skb(skb1); }