linux-stable/net
Eric Dumazet 0e280af026 tcp: introduce TCPSpuriousRtxHostQueues SNMP counter
Host queues (Qdisc + NIC) can hold packets so long that TCP can
eventually retransmit a packet before the first transmit even left
the host.

Its not clear right now if we could avoid this in the first place :

- We could arm RTO timer not at the time we enqueue packets, but
  at the time we TX complete them (tcp_wfree())

- Cancel the sending of the new copy of the packet if prior one
  is still in queue.

This patch adds instrumentation so that we can at least see how
often this problem happens.

TCPSpuriousRtxHostQueues SNMP counter is incremented every time
we detect the fast clone is not yet freed in tcp_transmit_skb()

Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Yuchung Cheng <ycheng@google.com>
Cc: Neal Cardwell <ncardwell@google.com>
Cc: Tom Herbert <therbert@google.com>
Cc: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-04-18 14:57:25 -04:00
..
9p Revert parts of "hlist: drop the node parameter from iterators" 2013-03-08 15:05:34 -08:00
802 802: fix a possible race condition 2013-04-07 17:04:17 -04:00
8021q 8021q: fix a potential use-after-free 2013-03-24 17:27:28 -04:00
appletalk hlist: drop the node parameter from iterators 2013-02-27 19:10:24 -08:00
atm Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2013-04-07 18:37:01 -04:00
ax25 ax25: fix info leak via msg_name in ax25_recvmsg() 2013-04-07 16:28:00 -04:00
batman-adv batman-adv: use seq_puts instead of seq_printf when the format is constant 2013-03-27 10:29:55 +01:00
bluetooth Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/linville/wireless-next into for-davem 2013-04-10 10:39:27 -04:00
bridge Merge branch 'master' of git://1984.lsi.us.es/nf-next 2013-04-07 12:22:06 -04:00
caif Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2013-04-07 18:37:01 -04:00
can net: sock: make sock_tx_timestamp void 2013-04-14 15:41:49 -04:00
ceph Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client 2013-03-12 09:22:42 -07:00
core neighbour: Convert NEIGH_PRINTK to neigh_dbg 2013-04-16 16:34:08 -04:00
dcb rtnetlink: Remove passing of attributes into rtnl_doit functions 2013-03-22 10:31:16 -04:00
dccp tcp: Remove TCPCT 2013-03-17 14:35:13 -04:00
decnet decnet: remove duplicated include from dn_table.c 2013-04-07 17:12:01 -04:00
dns_resolver Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security 2012-12-16 15:40:50 -08:00
dsa dsa: fix freeing of sparse port allocation 2013-03-25 12:23:41 -04:00
ethernet net: add ETH_P_802_3_MIN 2013-03-28 01:20:42 -04:00
ieee802154 ieee802154/nl-mac.c: make some MLME operations optional 2013-04-08 12:00:16 -04:00
ipv4 tcp: introduce TCPSpuriousRtxHostQueues SNMP counter 2013-04-18 14:57:25 -04:00
ipv6 net: sock: make sock_tx_timestamp void 2013-04-14 15:41:49 -04:00
ipx hlist: drop the node parameter from iterators 2013-02-27 19:10:24 -08:00
irda TTY: ircomm, use GFP_KERNEL in ircomm_open() 2013-04-08 12:09:18 -04:00
iucv Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2013-04-07 18:37:01 -04:00
key Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/klassert/ipsec 2013-03-27 14:07:04 -04:00
l2tp Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2013-04-07 18:37:01 -04:00
lapb net/lapb: remove depends on CONFIG_EXPERIMENTAL 2013-01-11 11:40:01 -08:00
llc llc: Fix missing msg_namelen update in llc_ui_recvmsg() 2013-04-07 16:28:01 -04:00
mac80211 Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/linville/wireless-next into for-davem 2013-04-10 10:39:27 -04:00
mac802154 mac802154: Keep track of the channel when changed 2013-04-08 12:09:18 -04:00
netfilter Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2013-04-07 18:37:01 -04:00
netlabel netlabel: fix build problems when CONFIG_IPV6=n 2013-03-08 11:33:51 -05:00
netlink net-next: replace obsolete NLMSG_* with type safe nlmsg_* 2013-03-28 14:25:25 -04:00
netrom netrom: fix info leak via msg_name in nr_recvmsg() 2013-04-07 16:28:02 -04:00
nfc Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/linville/wireless 2013-04-10 09:31:39 -04:00
openvswitch openvswitch: Use generic struct pcpu_tstats. 2013-04-15 14:56:25 -07:00
packet packet: minor: add generic tpacket_uhdr to access packet headers 2013-04-16 16:43:34 -04:00
phonet rtnetlink: Remove passing of attributes into rtnl_doit functions 2013-03-22 10:31:16 -04:00
rds net/rds: zero last byte for strncpy 2013-03-08 00:35:44 -05:00
rfkill net: rfkill: Fix sparse warning in rfkill-regulator.c 2013-03-06 16:35:41 +01:00
rose rose: fix info leak via msg_name in rose_recvmsg() 2013-04-07 16:28:02 -04:00
rxrpc Driver core patches for 3.9-rc1 2013-02-21 12:05:51 -08:00
sched act_csum: fix possible use after free 2013-04-12 15:25:41 -04:00
sctp net: sctp: sctp_ulpq: remove 'malloced' struct member 2013-04-17 14:13:02 -04:00
sunrpc NFS client bugfixes for Linux 3.9 2013-03-26 14:23:45 -07:00
tipc tipc: add InfiniBand media type 2013-04-17 14:18:33 -04:00
unix scm: Stop passing struct cred 2013-04-07 18:58:55 -04:00
vmw_vsock Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2013-04-07 18:37:01 -04:00
wimax
wireless Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/linville/wireless-next into for-davem 2013-04-10 10:39:27 -04:00
x25 hlist: drop the node parameter from iterators 2013-02-27 19:10:24 -08:00
xfrm Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/klassert/ipsec-next 2013-04-11 16:14:37 -04:00
compat.c
Kconfig netlink: Diag core and basic socket info dumping (v2) 2013-03-21 12:38:03 -04:00
Makefile VSOCK: Introduce VM Sockets 2013-02-10 19:41:08 -05:00
nonet.c
socket.c net: sock: make sock_tx_timestamp void 2013-04-14 15:41:49 -04:00
sysctl_net.c