Commit b56ea298 authored by Rick Jones's avatar Rick Jones Committed by David S. Miller
Browse files

net: track success and failure of TCP PMTU probing 



Track success and failure of TCP PMTU probing.

Signed-off-by: default avatarRick Jones <rick.jones2@hp.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 0b2c2a93

include/uapi/linux/snmp.h

+2 −0
Original line number Diff line number Diff line
@@ -278,6 +278,8 @@ enum 
	LINUX_MIB_TCPACKSKIPPEDCHALLENGE,	/* TCPACKSkippedChallenge */

	LINUX_MIB_TCPWINPROBE,			/* TCPWinProbe */

	LINUX_MIB_TCPKEEPALIVE,			/* TCPKeepAlive */

	LINUX_MIB_TCPMTUPFAIL,			/* TCPMTUPFail */

	LINUX_MIB_TCPMTUPSUCCESS,		/* TCPMTUPSuccess */

	__LINUX_MIB_MAX

};

net/ipv4/proc.c

+2 −0
Original line number Diff line number Diff line
@@ -300,6 +300,8 @@ static const struct snmp_mib snmp4_net_list[] = { 
	SNMP_MIB_ITEM("TCPACKSkippedChallenge", LINUX_MIB_TCPACKSKIPPEDCHALLENGE),

	SNMP_MIB_ITEM("TCPWinProbe", LINUX_MIB_TCPWINPROBE),

	SNMP_MIB_ITEM("TCPKeepAlive", LINUX_MIB_TCPKEEPALIVE),

	SNMP_MIB_ITEM("TCPMTUPFail", LINUX_MIB_TCPMTUPFAIL),

	SNMP_MIB_ITEM("TCPMTUPSuccess", LINUX_MIB_TCPMTUPSUCCESS),

	SNMP_MIB_SENTINEL

};

net/ipv4/tcp_input.c

+2 −0
Original line number Diff line number Diff line
@@ -2593,6 +2593,7 @@ static void tcp_mtup_probe_failed(struct sock *sk) 


	icsk->icsk_mtup.search_high = icsk->icsk_mtup.probe_size - 1;

	icsk->icsk_mtup.probe_size = 0;

	NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_TCPMTUPFAIL);

}



static void tcp_mtup_probe_success(struct sock *sk)
@@ -2612,6 +2613,7 @@ static void tcp_mtup_probe_success(struct sock *sk) 
	icsk->icsk_mtup.search_low = icsk->icsk_mtup.probe_size;

	icsk->icsk_mtup.probe_size = 0;

	tcp_sync_mss(sk, icsk->icsk_pmtu_cookie);

	NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_TCPMTUPSUCCESS);

}



/* Do a simple retransmit without using the backoff mechanisms in