* [PATCH net-next] tcp: add SNMP counter for zero-window drops
@ 2018-06-24 14:02 Yafang Shao
2018-06-25 17:26 ` Eric Dumazet
2018-06-26 2:50 ` David Miller
0 siblings, 2 replies; 5+ messages in thread
From: Yafang Shao @ 2018-06-24 14:02 UTC (permalink / raw)
To: davem; +Cc: netdev, Yafang Shao
It will be helpful if we could display the drops due to zero window or no
enough window space.
So a new SNMP MIB entry is added to track this behavior.
This entry is named LINUX_MIB_TCPZEROWINDOWDROP and published in
/proc/net/netstat in TcpExt line as TCPZeroWindowDrop.
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(-)
diff --git a/include/uapi/linux/snmp.h b/include/uapi/linux/snmp.h
index 750d891..97517f3 100644
--- a/include/uapi/linux/snmp.h
+++ b/include/uapi/linux/snmp.h
@@ -279,6 +279,7 @@ enum
LINUX_MIB_TCPDELIVERED, /* TCPDelivered */
LINUX_MIB_TCPDELIVEREDCE, /* TCPDeliveredCE */
LINUX_MIB_TCPACKCOMPRESSED, /* TCPAckCompressed */
+ LINUX_MIB_TCPZEROWINDOWDROP, /* TCPZeroWindowDrop */
__LINUX_MIB_MAX
};
diff --git a/net/ipv4/proc.c b/net/ipv4/proc.c
index 77350c1..225ef34 100644
--- a/net/ipv4/proc.c
+++ b/net/ipv4/proc.c
@@ -287,6 +287,7 @@ static int sockstat_seq_show(struct seq_file *seq, void *v)
SNMP_MIB_ITEM("TCPDelivered", LINUX_MIB_TCPDELIVERED),
SNMP_MIB_ITEM("TCPDeliveredCE", LINUX_MIB_TCPDELIVEREDCE),
SNMP_MIB_ITEM("TCPAckCompressed", LINUX_MIB_TCPACKCOMPRESSED),
+ SNMP_MIB_ITEM("TCPZeroWindowDrop", LINUX_MIB_TCPZEROWINDOWDROP),
SNMP_MIB_SENTINEL
};
diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c
index 76ca88f..9c5b341 100644
--- a/net/ipv4/tcp_input.c
+++ b/net/ipv4/tcp_input.c
@@ -4668,8 +4668,10 @@ static void tcp_data_queue(struct sock *sk, struct sk_buff *skb)
* Out of sequence packets to the out_of_order_queue.
*/
if (TCP_SKB_CB(skb)->seq == tp->rcv_nxt) {
- if (tcp_receive_window(tp) == 0)
+ if (tcp_receive_window(tp) == 0) {
+ NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPZEROWINDOWDROP);
goto out_of_window;
+ }
/* Ok. In sequence. In window. */
queue_and_out:
@@ -4735,8 +4737,10 @@ static void tcp_data_queue(struct sock *sk, struct sk_buff *skb)
/* If window is closed, drop tail of packet. But after
* remembering D-SACK for its head made in previous line.
*/
- if (!tcp_receive_window(tp))
+ if (!tcp_receive_window(tp)) {
+ NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPZEROWINDOWDROP);
goto out_of_window;
+ }
goto queue_and_out;
}
--
1.8.3.1
^ permalink raw reply related [flat|nested] 5+ messages in thread* [PATCH net-next] tcp: add SNMP counter for zero-window drops
@ 2018-06-13 11:38 Yafang Shao
2018-06-15 0:09 ` David Miller
0 siblings, 1 reply; 5+ messages in thread
From: Yafang Shao @ 2018-06-13 11:38 UTC (permalink / raw)
To: edumazet, davem; +Cc: netdev, linux-kernel, Yafang Shao
It will be helpful if we could display the drops due to zero window or no
enough window space.
So a new SNMP MIB entry is added to track this behavior.
This entry is named LINUX_MIB_TCPZEROWINDOWDROP and published in
/proc/net/netstat in TcpExt line as TCPZeroWindowDrop.
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(-)
diff --git a/include/uapi/linux/snmp.h b/include/uapi/linux/snmp.h
index 750d891..97517f3 100644
--- a/include/uapi/linux/snmp.h
+++ b/include/uapi/linux/snmp.h
@@ -279,6 +279,7 @@ enum
LINUX_MIB_TCPDELIVERED, /* TCPDelivered */
LINUX_MIB_TCPDELIVEREDCE, /* TCPDeliveredCE */
LINUX_MIB_TCPACKCOMPRESSED, /* TCPAckCompressed */
+ LINUX_MIB_TCPZEROWINDOWDROP, /* TCPZeroWindowDrop */
__LINUX_MIB_MAX
};
diff --git a/net/ipv4/proc.c b/net/ipv4/proc.c
index 77350c1..225ef34 100644
--- a/net/ipv4/proc.c
+++ b/net/ipv4/proc.c
@@ -287,6 +287,7 @@ static int sockstat_seq_show(struct seq_file *seq, void *v)
SNMP_MIB_ITEM("TCPDelivered", LINUX_MIB_TCPDELIVERED),
SNMP_MIB_ITEM("TCPDeliveredCE", LINUX_MIB_TCPDELIVEREDCE),
SNMP_MIB_ITEM("TCPAckCompressed", LINUX_MIB_TCPACKCOMPRESSED),
+ SNMP_MIB_ITEM("TCPZeroWindowDrop", LINUX_MIB_TCPZEROWINDOWDROP),
SNMP_MIB_SENTINEL
};
diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c
index 355d3df..b0482b1 100644
--- a/net/ipv4/tcp_input.c
+++ b/net/ipv4/tcp_input.c
@@ -4665,8 +4665,10 @@ static void tcp_data_queue(struct sock *sk, struct sk_buff *skb)
* Out of sequence packets to the out_of_order_queue.
*/
if (TCP_SKB_CB(skb)->seq == tp->rcv_nxt) {
- if (tcp_receive_window(tp) == 0)
+ if (tcp_receive_window(tp) == 0) {
+ NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPZEROWINDOWDROP);
goto out_of_window;
+ }
/* Ok. In sequence. In window. */
queue_and_out:
@@ -4732,8 +4734,10 @@ static void tcp_data_queue(struct sock *sk, struct sk_buff *skb)
/* If window is closed, drop tail of packet. But after
* remembering D-SACK for its head made in previous line.
*/
- if (!tcp_receive_window(tp))
+ if (!tcp_receive_window(tp)) {
+ NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPZEROWINDOWDROP);
goto out_of_window;
+ }
goto queue_and_out;
}
--
1.8.3.1
^ permalink raw reply related [flat|nested] 5+ messages in thread* Re: [PATCH net-next] tcp: add SNMP counter for zero-window drops
2018-06-13 11:38 Yafang Shao
@ 2018-06-15 0:09 ` David Miller
0 siblings, 0 replies; 5+ messages in thread
From: David Miller @ 2018-06-15 0:09 UTC (permalink / raw)
To: laoar.shao; +Cc: edumazet, netdev, linux-kernel
From: Yafang Shao <laoar.shao@gmail.com>
Date: Wed, 13 Jun 2018 07:38:28 -0400
> It will be helpful if we could display the drops due to zero window or no
> enough window space.
> So a new SNMP MIB entry is added to track this behavior.
> This entry is named LINUX_MIB_TCPZEROWINDOWDROP and published in
> /proc/net/netstat in TcpExt line as TCPZeroWindowDrop.
>
> Signed-off-by: Yafang Shao <laoar.shao@gmail.com>
net-next is closed, please resubmit this when net-next opens
back up.
Thank you.
^ permalink raw reply [flat|nested] 5+ messages in thread
end of thread, other threads:[~2018-06-26 2:50 UTC | newest]
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2018-06-24 14:02 [PATCH net-next] tcp: add SNMP counter for zero-window drops Yafang Shao
2018-06-25 17:26 ` Eric Dumazet
2018-06-26 2:50 ` David Miller
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2018-06-13 11:38 Yafang Shao
2018-06-15 0:09 ` David Miller
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