linux/net/ipv6
Eric Dumazet e6c022a4fa tcp: better retrans tracking for defer-accept
For passive TCP connections using TCP_DEFER_ACCEPT facility,
we incorrectly increment req->retrans each time timeout triggers
while no SYNACK is sent.

SYNACK are not sent for TCP_DEFER_ACCEPT that were established (for
which we received the ACK from client). Only the last SYNACK is sent
so that we can receive again an ACK from client, to move the req into
accept queue. We plan to change this later to avoid the useless
retransmit (and potential problem as this SYNACK could be lost)

TCP_INFO later gives wrong information to user, claiming imaginary
retransmits.

Decouple req->retrans field into two independent fields :

num_retrans : number of retransmit
num_timeout : number of timeouts

num_timeout is the counter that is incremented at each timeout,
regardless of actual SYNACK being sent or not, and used to
compute the exponential timeout.

Introduce inet_rtx_syn_ack() helper to increment num_retrans
only if ->rtx_syn_ack() succeeded.

Use inet_rtx_syn_ack() from tcp_check_req() to increment num_retrans
when we re-send a SYNACK in answer to a (retransmitted) SYN.
Prior to this patch, we were not counting these retransmits.

Change tcp_v[46]_rtx_synack() to increment TCP_MIB_RETRANSSEGS
only if a synack packet was successfully queued.

Reported-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Julian Anastasov <ja@ssi.bg>
Cc: Vijay Subramanian <subramanian.vijay@gmail.com>
Cc: Elliott Hughes <enh@google.com>
Cc: Neal Cardwell <ncardwell@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-11-03 14:45:00 -04:00
..
netfilter ipv6: use IS_ENABLED() 2012-11-01 12:41:35 -04:00
addrconf_core.c net: cleanup unsigned to unsigned int 2012-04-15 12:44:40 -04:00
addrconf.c ipv6: use IS_ENABLED() 2012-11-01 12:41:35 -04:00
addrlabel.c sections: fix section conflicts in net 2012-10-06 03:04:45 +09:00
af_inet6.c ipv6: gro: fix PV6_GRO_CB(skb)->proto problem 2012-10-08 15:40:43 -04:00
ah6.c ipv6: use IS_ENABLED() 2012-11-01 12:41:35 -04:00
anycast.c ipv6: bool/const conversions phase2 2012-05-19 01:08:16 -04:00
datagram.c ipv6: use IS_ENABLED() 2012-11-01 12:41:35 -04:00
esp6.c net: ipv6: fix error return code 2012-08-31 16:27:48 -04:00
exthdrs_core.c ipv6: bool/const conversions phase2 2012-05-19 01:08:16 -04:00
exthdrs.c ipv6: use IS_ENABLED() 2012-11-01 12:41:35 -04:00
fib6_rules.c sections: fix section conflicts in net 2012-10-06 03:04:45 +09:00
icmp.c ipv6: use IS_ENABLED() 2012-11-01 12:41:35 -04:00
inet6_connection_sock.c ipv6: use net->rt_genid to check dst validity 2012-09-18 15:57:03 -04:00
inet6_hashtables.c net: Compute protocol sequence numbers and fragment IDs using MD5. 2011-08-06 18:33:19 -07:00
ip6_fib.c ipv6: add support of equal cost multipath (ECMP) 2012-10-23 02:38:32 -04:00
ip6_flowlabel.c ipv6: move dereference after check in fl_free() 2012-08-16 16:04:42 -07:00
ip6_gre.c ipv6: gre: remove ip6gre_header_parse() 2012-09-27 18:49:22 -04:00
ip6_input.c net: TCP early demux cleanup 2012-07-30 14:53:21 -07:00
ip6_output.c ipv6: use IS_ENABLED() 2012-11-01 12:41:35 -04:00
ip6_tunnel.c gre: information leak in ip6_tnl_ioctl() 2012-08-20 02:21:30 -07:00
ip6mr.c sections: fix section conflicts in net 2012-10-06 03:04:45 +09:00
ipcomp6.c ipv6: Add redirect support to all protocol icmp error handlers. 2012-07-12 00:25:15 -07:00
ipv6_sockglue.c ipv6: use IS_ENABLED() 2012-11-01 12:41:35 -04:00
Kconfig gre: Support GRE over IPv6 2012-08-14 14:28:32 -07:00
Makefile gre: Support GRE over IPv6 2012-08-14 14:28:32 -07:00
mcast.c ipv6: fix unappropriate errno returned for non-multicast address 2012-07-17 01:35:03 -07:00
mip6.c ipv6: mip6: fix mip6_mh_filter() 2012-09-25 16:04:44 -04:00
ndisc.c ipv6: Use icmpv6_notify() to propagate redirect, instead of rt6_redirect(). 2012-07-12 00:33:37 -07:00
netfilter.c netfilter: ipv6: expand skb head in ip6_route_me_harder after oif change 2012-08-30 03:00:15 +02:00
proc.c net: ipv6: proc: Fix error handling 2012-08-14 14:45:07 -07:00
protocol.c inet: Sanitize inet{,6} protocol demux. 2012-06-19 18:56:21 -07:00
raw.c ipv6: use IS_ENABLED() 2012-11-01 12:41:35 -04:00
reassembly.c ipv6: unify fragment thresh handling code 2012-09-19 17:23:28 -04:00
route.c ipv6/multipath: remove flag NLM_F_EXCL after the first nexthop 2012-11-02 21:38:19 -04:00
sit.c xfrm: remove extranous rcu_read_lock 2012-09-27 18:12:37 -04:00
syncookies.c tcp: better retrans tracking for defer-accept 2012-11-03 14:45:00 -04:00
sysctl_net_ipv6.c net: Delete all remaining instances of ctl_path 2012-04-20 21:22:30 -04:00
tcp_ipv6.c tcp: better retrans tracking for defer-accept 2012-11-03 14:45:00 -04:00
tunnel6.c net: ipv6: Standardize prefixes for message logging 2012-05-16 01:01:03 -04:00
udp_impl.h
udp.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2012-09-15 11:43:53 -04:00
udplite.c Merge branch 'modsplit-Oct31_2011' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux 2011-11-06 19:44:47 -08:00
xfrm6_input.c netfilter: ipv6: use NFPROTO values for NF_HOOK invocation 2010-03-25 16:00:49 +01:00
xfrm6_mode_beet.c ipsec: be careful of non existing mac headers 2012-02-23 16:50:45 -05:00
xfrm6_mode_ro.c
xfrm6_mode_transport.c
xfrm6_mode_tunnel.c ipsec: be careful of non existing mac headers 2012-02-23 16:50:45 -05:00
xfrm6_output.c xfrm6: remove unneeded NULL check in __xfrm6_output() 2012-02-01 02:52:48 -05:00
xfrm6_policy.c ipv6: use IS_ENABLED() 2012-11-01 12:41:35 -04:00
xfrm6_state.c ipv6: use IS_ENABLED() 2012-11-01 12:41:35 -04:00
xfrm6_tunnel.c net: cleanup unsigned to unsigned int 2012-04-15 12:44:40 -04:00