linux/net/ipv6
Eric Dumazet c9c3321257 tcp: add tcp_add_backlog()
When TCP operates in lossy environments (between 1 and 10 % packet
losses), many SACK blocks can be exchanged, and I noticed we could
drop them on busy senders, if these SACK blocks have to be queued
into the socket backlog.

While the main cause is the poor performance of RACK/SACK processing,
we can try to avoid these drops of valuable information that can lead to
spurious timeouts and retransmits.

Cause of the drops is the skb->truesize overestimation caused by :

- drivers allocating ~2048 (or more) bytes as a fragment to hold an
  Ethernet frame.

- various pskb_may_pull() calls bringing the headers into skb->head
  might have pulled all the frame content, but skb->truesize could
  not be lowered, as the stack has no idea of each fragment truesize.

The backlog drops are also more visible on bidirectional flows, since
their sk_rmem_alloc can be quite big.

Let's add some room for the backlog, as only the socket owner
can selectively take action to lower memory needs, like collapsing
receive queues or partial ofo pruning.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Yuchung Cheng <ycheng@google.com>
Cc: Neal Cardwell <ncardwell@google.com>
Acked-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-08-29 00:20:24 -04:00
..
ila kcm: Use stream parser 2016-08-17 19:36:23 -04:00
netfilter netfilter: x_tables: speed up jump target validation 2016-07-18 21:35:23 +02:00
addrconf_core.c ipv6: change ipv6_stub_impl.ipv6_dst_lookup to take net argument 2015-07-31 15:21:30 -07:00
addrconf.c net: ipv6: Do not keep IPv6 addresses when IPv6 is disabled 2016-08-13 15:14:00 -07:00
addrlabel.c ipv6/addrlabel: fix ip6addrlbl_get() 2015-12-22 15:57:54 -05:00
af_inet6.c tcp: Set read_sock and peek_len proto_ops 2016-08-28 23:32:41 -04:00
ah6.c ah6: fix error return code 2015-08-25 13:37:31 -07:00
anycast.c ipv6: coding style: comparison for equality with NULL 2015-03-31 13:51:54 -04:00
calipso.c calipso: fix resource leak on calipso_genopt failure 2016-08-13 14:56:17 -07:00
datagram.c sock: propagate __sock_cmsg_send() error 2016-05-16 13:46:23 -04:00
esp6.c esp6: Switch to new AEAD interface 2015-05-28 11:23:20 +08:00
exthdrs_core.c ipv6: constify the skb pointer of ipv6_find_tlv(). 2016-06-27 15:06:15 -04:00
exthdrs_offload.c ipv6: fix exthdrs offload registration in out_rt path 2015-09-02 15:31:00 -07:00
exthdrs.c Merge branch 'stable-4.8' of git://git.infradead.org/users/pcmoore/selinux into next 2016-07-07 10:15:34 +10:00
fib6_rules.c net: Add l3mdev rule 2016-06-08 11:36:02 -07:00
fou6.c fou: add Kconfig options for IPv6 support 2016-05-29 22:24:21 -07:00
icmp.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2016-06-30 05:03:36 -04:00
inet6_connection_sock.c soreuseport: fast reuseport TCP socket selection 2016-02-11 03:54:15 -05:00
inet6_hashtables.c net: rename NET_{ADD|INC}_STATS_BH() 2016-04-27 22:48:24 -04:00
ip6_checksum.c ipv6: fix checksum annotation in udp6_csum_init 2016-06-14 15:26:42 -04:00
ip6_fib.c ipv6: Fix mem leak in rt6i_pcpu 2016-07-05 14:09:23 -07:00
ip6_flowlabel.c ipv6: add new struct ipcm6_cookie 2016-05-03 16:08:14 -04:00
ip6_gre.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2016-08-18 01:17:32 -04:00
ip6_icmp.c ipv6: icmp: add a force_saddr param to icmp6_send() 2016-06-18 22:11:38 -07:00
ip6_input.c net: vrf: ipv6 support for local traffic to local addresses 2016-06-08 00:25:38 -07:00
ip6_offload.c ip4ip6: Support for GSO/GRO 2016-05-20 18:03:17 -04:00
ip6_offload.h udp: Add GRO functions to UDP socket 2016-04-07 16:53:29 -04:00
ip6_output.c net: vrf: Implement get_saddr for IPv6 2016-06-17 21:25:29 -07:00
ip6_tunnel.c net: resolve symbol conflicts with generic hashtable.h 2016-08-10 17:18:52 -07:00
ip6_udp_tunnel.c ip_tunnel: add support for setting flow label via collect metadata 2016-03-11 15:14:26 -05:00
ip6_vti.c net: resolve symbol conflicts with generic hashtable.h 2016-08-10 17:18:52 -07:00
ip6mr.c net: ipmr/ip6mr: update lastuse on entry change 2016-07-26 15:18:31 -07:00
ipcomp6.c ipv6: White-space cleansing : Structure layouts 2014-08-24 22:37:52 -07:00
ipv6_sockglue.c Merge branch 'stable-4.8' of git://git.infradead.org/users/pcmoore/selinux into next 2016-07-07 10:15:34 +10:00
Kconfig fou: fix IPv6 Kconfig options 2016-05-31 14:07:49 -07:00
Makefile Merge branch 'stable-4.8' of git://git.infradead.org/users/pcmoore/selinux into next 2016-07-07 10:15:34 +10:00
mcast_snoop.c net: fix wrong skb_get() usage / crash in IGMP/MLD parsing code 2015-08-13 17:08:39 -07:00
mcast.c net/multicast: should not send source list records when have filter mode change 2016-08-08 16:04:39 -07:00
mip6.c ipv6: use ktime_t for internal timestamps 2015-10-05 03:16:47 -07:00
ndisc.c ipv6: export several functions 2016-06-15 20:41:23 -07:00
netfilter.c ipv6: Pass struct net into ip6_route_me_harder 2015-09-29 20:21:32 +02:00
output_core.c ipv4, ipv6: Pass net into ip_local_out and ip6_local_out 2015-10-08 04:27:02 -07:00
ping.c net: ipv6: Fix ping to link-local addresses. 2016-08-15 12:19:09 -07:00
proc.c udp: Increment UDP_MIB_IGNOREDMULTI for arriving unmatched multicasts 2014-11-07 15:45:50 -05:00
protocol.c net: Export inet_offloads and inet6_offloads 2014-09-19 17:15:31 -04:00
raw.c ipv6: use TOS marks from sockets for routing decision 2016-06-11 15:33:26 -07:00
reassembly.c ipv6: rename IP6_INC_STATS_BH() 2016-04-27 22:48:24 -04:00
route.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2016-06-30 05:03:36 -04:00
sit.c sit: make function ipip6_valid_ip_proto() static 2016-08-12 21:52:18 -07:00
syncookies.c net: rename NET_{ADD|INC}_STATS_BH() 2016-04-27 22:48:24 -04:00
sysctl_net_ipv6.c calipso: Add a label cache. 2016-06-27 15:06:17 -04:00
tcp_ipv6.c tcp: add tcp_add_backlog() 2016-08-29 00:20:24 -04:00
tcpv6_offload.c tcp: cleanup static functions 2015-02-28 16:56:51 -05:00
tunnel6.c ipv6: fix tunnel error handling 2015-11-03 10:52:13 -05:00
udp_impl.h ipv6: udp: remove udp_v6_clear_sk() 2016-08-23 23:23:50 -07:00
udp_offload.c gso: Remove arbitrary checks for unsupported GSO 2016-05-20 18:03:15 -04:00
udp.c ipv6: udp: remove udp_v6_clear_sk() 2016-08-23 23:23:50 -07:00
udplite.c udp: get rid of sk_prot_clear_portaddr_nulls() 2016-08-23 23:25:29 -07:00
xfrm6_input.c netfilter: Pass struct net into the netfilter hooks 2015-09-17 17:18:37 -07:00
xfrm6_mode_beet.c xfrm: simplify xfrm_address_t use 2015-03-31 13:58:35 -04:00
xfrm6_mode_ro.c
xfrm6_mode_transport.c
xfrm6_mode_tunnel.c ipv6: update skb->csum when CE mark is propagated 2016-01-15 15:07:23 -05:00
xfrm6_output.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2015-10-24 06:54:12 -07:00
xfrm6_policy.c net: xfrm: fix old-style declaration 2016-06-16 22:06:30 -07:00
xfrm6_protocol.c xfrm6: Properly handle unsupported protocols 2014-05-06 07:08:38 +02:00
xfrm6_state.c ipv6: White-space cleansing : Line Layouts 2014-08-24 22:37:52 -07:00
xfrm6_tunnel.c ipv6: White-space cleansing : gaps between function and symbol export 2014-08-24 22:37:52 -07:00