linux/net/ipv4
Willy Tarreau bad115cfe5 tcp: do_tcp_sendpages() must try to push data out on oom conditions
Since recent changes on TCP splicing (starting with commits 2f533844
"tcp: allow splice() to build full TSO packets" and 35f9c09f "tcp:
tcp_sendpages() should call tcp_push() once"), I started seeing
massive stalls when forwarding traffic between two sockets using
splice() when pipe buffers were larger than socket buffers.

Latest changes (net: netdev_alloc_skb() use build_skb()) made the
problem even more apparent.

The reason seems to be that if do_tcp_sendpages() fails on out of memory
condition without being able to send at least one byte, tcp_push() is not
called and the buffers cannot be flushed.

After applying the attached patch, I cannot reproduce the stalls at all
and the data rate it perfectly stable and steady under any condition
which previously caused the problem to be permanent.

The issue seems to have been there since before the kernel migrated to
git, which makes me think that the stalls I occasionally experienced
with tux during stress-tests years ago were probably related to the
same issue.

This issue was first encountered on 3.0.31 and 3.2.17, so please backport
to -stable.

Signed-off-by: Willy Tarreau <w@1wt.eu>
Acked-by: Eric Dumazet <edumazet@google.com>
Cc: <stable@vger.kernel.org>
2012-05-17 18:31:43 -04:00
..
netfilter netfilter: nf_ct_ipv4: packets with wrong ihl are invalid 2012-04-10 12:50:49 +02:00
af_inet.c Remove all #inclusions of asm/system.h 2012-03-28 18:30:03 +01:00
ah4.c net: ipv4: Standardize prefixes for message logging 2012-03-12 17:05:21 -07:00
arp.c Remove all #inclusions of asm/system.h 2012-03-28 18:30:03 +01:00
cipso_ipv4.c ipv4: Convert call_rcu() to kfree_rcu(), drop opt_kfree_rcu() 2012-02-21 09:03:31 -08:00
datagram.c ipv4: Lock socket and use cork flow in ip4_datagram_connect(). 2011-05-08 13:48:57 -07:00
devinet.c Disintegrate and delete asm/system.h 2012-03-28 15:58:21 -07:00
esp4.c net: ipv4: Standardize prefixes for message logging 2012-03-12 17:05:21 -07:00
fib_frontend.c Remove all #inclusions of asm/system.h 2012-03-28 18:30:03 +01:00
fib_lookup.h ipv4: Fix nexthop caching wrt. scoping. 2011-03-24 18:06:47 -07:00
fib_rules.c net: ipv4: export fib_lookup and fib_table_lookup 2011-12-04 22:43:33 +01:00
fib_semantics.c Remove all #inclusions of asm/system.h 2012-03-28 18:30:03 +01:00
fib_trie.c ipv4: Do not use dead fib_info entries. 2012-05-10 22:16:32 -04:00
gre.c net: ipv4: Standardize prefixes for message logging 2012-03-12 17:05:21 -07:00
icmp.c Remove all #inclusions of asm/system.h 2012-03-28 18:30:03 +01:00
igmp.c Remove all #inclusions of asm/system.h 2012-03-28 18:30:03 +01:00
inet_connection_sock.c tcp: bind() optimize port allocation 2012-01-25 21:50:43 -05:00
inet_diag.c udp_diag: implement idiag_get_info for udp/udplite to get queue information 2012-04-25 20:43:01 -04:00
inet_fragment.c net/ipv4: EXPORT_SYMBOL cleanups 2010-07-12 12:57:54 -07:00
inet_hashtables.c net: Compute protocol sequence numbers and fragment IDs using MD5. 2011-08-06 18:33:19 -07:00
inet_lro.c net: add skb frag size accessors 2011-10-19 03:10:46 -04:00
inet_timewait_sock.c net: Fix files explicitly needing to include module.h 2011-10-31 19:30:28 -04:00
inetpeer.c route: Remove redirect_genid 2012-03-08 00:30:32 -08:00
ip_forward.c ipv4: Save nexthop address of LSRR/SSRR option to IPCB. 2011-11-23 19:19:32 -05:00
ip_fragment.c net: ipv4: Standardize prefixes for message logging 2012-03-12 17:05:21 -07:00
ip_gre.c net: ipv4: Standardize prefixes for message logging 2012-03-12 17:05:21 -07:00
ip_input.c Remove all #inclusions of asm/system.h 2012-03-28 18:30:03 +01:00
ip_options.c net: ipv4: Standardize prefixes for message logging 2012-03-12 17:05:21 -07:00
ip_output.c Remove all #inclusions of asm/system.h 2012-03-28 18:30:03 +01:00
ip_sockglue.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2012-03-20 21:04:47 -07:00
ipcomp.c net: Convert printks to pr_<level> 2012-03-11 23:42:51 -07:00
ipconfig.c net: Convert printks to pr_<level> 2012-03-11 23:42:51 -07:00
ipip.c net: Convert printks to pr_<level> 2012-03-11 23:42:51 -07:00
ipmr.c Remove all #inclusions of asm/system.h 2012-03-28 18:30:03 +01:00
Kconfig net: Fix build regression when INET_UDP_DIAG=y and IPV6=m 2012-02-07 13:35:28 -05:00
Makefile tcp memory pressure controls 2011-12-12 19:04:10 -05:00
netfilter.c netfilter: possible unaligned packet header in ip_route_me_harder 2011-11-21 18:46:18 +01:00
ping.c Remove all #inclusions of asm/system.h 2012-03-28 18:30:03 +01:00
proc.c tcp: reduce out_of_order memory use 2012-03-19 16:53:08 -04:00
protocol.c net: add __rcu annotations to protocol 2010-10-27 11:37:31 -07:00
raw.c net: Convert printks to pr_<level> 2012-03-11 23:42:51 -07:00
route.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2012-04-02 17:53:39 -07:00
syncookies.c tcp: fix syncookie regression 2012-03-11 15:52:12 -07:00
sysctl_net_ipv4.c tcp: properly initialize tcp memory limits 2012-02-02 14:34:41 -05:00
tcp_bic.c tcp: fix undo after RTO for BIC 2012-01-20 14:17:26 -05:00
tcp_cong.c net: ipv4: Standardize prefixes for message logging 2012-03-12 17:05:21 -07:00
tcp_cubic.c tcp: fix undo after RTO for CUBIC 2012-01-20 14:17:26 -05:00
tcp_diag.c inet_diag: Rename inet_diag_req into inet_diag_req_v2 2012-01-11 12:56:06 -08:00
tcp_highspeed.c tcp: mark tcp_congestion_ops read_mostly 2011-03-10 00:40:17 -08:00
tcp_htcp.c tcp: mark tcp_congestion_ops read_mostly 2011-03-10 00:40:17 -08:00
tcp_hybla.c tcp: mark tcp_congestion_ops read_mostly 2011-03-10 00:40:17 -08:00
tcp_illinois.c tcp: mark tcp_congestion_ops read_mostly 2011-03-10 00:40:17 -08:00
tcp_input.c tcp: change tcp_adv_win_scale and tcp_rmem[2] 2012-05-02 21:08:58 -04:00
tcp_ipv4.c dmaengine-fixes for 3.4-rc3 2012-04-10 15:30:16 -07:00
tcp_lp.c Fix common misspellings 2011-03-31 11:26:23 -03:00
tcp_memcontrol.c Merge branch 'for-3.4' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup 2012-03-20 18:11:21 -07:00
tcp_minisocks.c tcp: md5: rcu conversion 2012-01-31 12:14:00 -05:00
tcp_output.c tcp: fix retransmit of partially acked frames 2012-04-18 16:52:45 -04:00
tcp_probe.c net: ipv4: Standardize prefixes for message logging 2012-03-12 17:05:21 -07:00
tcp_scalable.c tcp: mark tcp_congestion_ops read_mostly 2011-03-10 00:40:17 -08:00
tcp_timer.c net: ipv4: Standardize prefixes for message logging 2012-03-12 17:05:21 -07:00
tcp_vegas.c tcp: mark tcp_congestion_ops read_mostly 2011-03-10 00:40:17 -08:00
tcp_vegas.h
tcp_veno.c tcp: mark tcp_congestion_ops read_mostly 2011-03-10 00:40:17 -08:00
tcp_westwood.c tcp: mark tcp_congestion_ops read_mostly 2011-03-10 00:40:17 -08:00
tcp_yeah.c Fix common misspellings 2011-03-31 11:26:23 -03:00
tcp.c tcp: do_tcp_sendpages() must try to push data out on oom conditions 2012-05-17 18:31:43 -04:00
tunnel4.c net: Convert printks to pr_<level> 2012-03-11 23:42:51 -07:00
udp_diag.c udp_diag: implement idiag_get_info for udp/udplite to get queue information 2012-04-25 20:43:01 -04:00
udp_impl.h
udp.c Remove all #inclusions of asm/system.h 2012-03-28 18:30:03 +01:00
udplite.c net: ipv4: Standardize prefixes for message logging 2012-03-12 17:05:21 -07:00
xfrm4_input.c net/ipv4: EXPORT_SYMBOL cleanups 2010-07-12 12:57:54 -07:00
xfrm4_mode_beet.c ipsec: be careful of non existing mac headers 2012-02-23 16:50:45 -05:00
xfrm4_mode_transport.c
xfrm4_mode_tunnel.c ipsec: be careful of non existing mac headers 2012-02-23 16:50:45 -05:00
xfrm4_output.c xfrm4: Don't call icmp_send on local error 2011-07-01 17:33:19 -07:00
xfrm4_policy.c ipv4: fix ipsec forward performance regression 2011-10-24 03:01:22 -04:00
xfrm4_state.c net: Add export.h for EXPORT_SYMBOL/THIS_MODULE to non-modules 2011-10-31 19:30:30 -04:00
xfrm4_tunnel.c net: ipv4: Standardize prefixes for message logging 2012-03-12 17:05:21 -07:00