@@ -280,6 +280,7 @@ enum
LINUX_MIB_TCPDELIVEREDCE, /* TCPDeliveredCE */
LINUX_MIB_TCPACKCOMPRESSED, /* TCPAckCompressed */
LINUX_MIB_TCPZEROWINDOWDROP, /* TCPZeroWindowDrop */
+ LINUX_MIB_TCPRCVQDROP, /* TCPRcvQDrop */
__LINUX_MIB_MAX
};
@@ -288,6 +288,7 @@ static int sockstat_seq_show(struct seq_file *seq, void *v)
SNMP_MIB_ITEM("TCPDeliveredCE", LINUX_MIB_TCPDELIVEREDCE),
SNMP_MIB_ITEM("TCPAckCompressed", LINUX_MIB_TCPACKCOMPRESSED),
SNMP_MIB_ITEM("TCPZeroWindowDrop", LINUX_MIB_TCPZEROWINDOWDROP),
+ SNMP_MIB_ITEM("TCPRcvQDrop", LINUX_MIB_TCPRCVQDROP),
SNMP_MIB_SENTINEL
};
@@ -4611,8 +4611,10 @@ int tcp_send_rcvq(struct sock *sk, struct msghdr *msg, size_t size)
skb->data_len = data_len;
skb->len = size;
- if (tcp_try_rmem_schedule(sk, skb, skb->truesize))
+ if (tcp_try_rmem_schedule(sk, skb, skb->truesize)) {
+ NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPRCVQDROP);
goto err_free;
+ }
err = skb_copy_datagram_from_iter(skb, 0, &msg->msg_iter, size);
if (err)
@@ -4677,8 +4679,10 @@ static void tcp_data_queue(struct sock *sk, struct sk_buff *skb)
queue_and_out:
if (skb_queue_len(&sk->sk_receive_queue) == 0)
sk_forced_mem_schedule(sk, skb->truesize);
- else if (tcp_try_rmem_schedule(sk, skb, skb->truesize))
+ else if (tcp_try_rmem_schedule(sk, skb, skb->truesize)) {
+ NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPRCVQDROP);
goto drop;
+ }
eaten = tcp_queue_rcv(sk, skb, 0, &fragstolen);
tcp_rcv_nxt_update(tp, TCP_SKB_CB(skb)->end_seq);
When sk_rmem_alloc is larger than the receive buffer and we can't schedule more memory for it, the skb will be dropped. In above situation, if this skb is put into the ofo queue, LINUX_MIB_TCPOFODROP is incremented to track it. While if this skb is put into the receive queue, there's no record. So a new SNMP counter is introduced to track this behavior. LINUX_MIB_TCPRCVQDROP: Number of packets meant to be queued in rcv queue but dropped because socket rcvbuf limit hit. Signed-off-by: Yafang Shao <laoar.shao@gmail.com> --- include/uapi/linux/snmp.h | 1 + net/ipv4/proc.c | 1 + net/ipv4/tcp_input.c | 8 ++++++-- 3 files changed, 8 insertions(+), 2 deletions(-)