WSL2-Linux-Kernel/net
Eric Dumazet 5d9f4262b7 tcp: add SACK compression
When TCP receives an out-of-order packet, it immediately sends
a SACK packet, generating network load but also forcing the
receiver to send 1-MSS pathological packets, increasing its
RTX queue length/depth, and thus processing time.

Wifi networks suffer from this aggressive behavior, but generally
speaking, all these SACK packets add fuel to the fire when networks
are under congestion.

This patch adds a high resolution timer and tp->compressed_ack counter.

Instead of sending a SACK, we program this timer with a small delay,
based on RTT and capped to 1 ms :

	delay = min ( 5 % of RTT, 1 ms)

If subsequent SACKs need to be sent while the timer has not yet
expired, we simply increment tp->compressed_ack.

When timer expires, a SACK is sent with the latest information.
Whenever an ACK is sent (if data is sent, or if in-order
data is received) timer is canceled.

Note that tcp_sack_new_ofo_skb() is able to force a SACK to be sent
if the sack blocks need to be shuffled, even if the timer has not
expired.

A new SNMP counter is added in the following patch.

Two other patches add sysctls to allow changing the 1,000,000 and 44
values that this commit hard-coded.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Neal Cardwell <ncardwell@google.com>
Acked-by: Yuchung Cheng <ycheng@google.com>
Acked-by: Toke Høiland-Jørgensen <toke@toke.dk>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-05-18 11:40:27 -04:00
..
6lowpan License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
9p Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2018-05-11 20:53:22 -04:00
802 treewide: setup_timer() -> timer_setup() 2017-11-21 15:57:07 -08:00
8021q vlan: Add extack messages for link create 2018-05-17 17:08:55 -04:00
appletalk net: Use octal not symbolic permissions 2018-03-26 12:07:48 -04:00
atm net: atm: Fix potential Spectre v1 2018-05-04 12:52:47 -04:00
ax25 net: Use octal not symbolic permissions 2018-03-26 12:07:48 -04:00
batman-adv Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2018-04-01 19:49:34 -04:00
bluetooth Merge branch 'for-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/bluetooth/bluetooth 2018-04-08 17:19:15 -04:00
bpf bpf: making bpf_prog_test run aware of possible data_end ptr change 2018-04-18 23:34:16 +02:00
bridge net: bridge: Allow bridge master in br_vlan_get_info() 2018-05-10 17:50:51 -04:00
caif net: caif: fix spelling mistake "UKNOWN" -> "UNKNOWN" 2018-04-19 13:37:10 -04:00
can net: Drop pernet_operations::async 2018-03-27 13:18:09 -04:00
ceph libceph: add osd_req_op_extent_osd_data_bvecs() 2018-05-10 10:15:05 +02:00
core Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next 2018-05-16 22:47:11 -04:00
dcb rtnetlink: make rtnl_register accept a flags parameter 2017-08-09 16:57:38 -07:00
dccp dccp: fix tasklet usage 2018-05-03 15:14:57 -04:00
decnet net: fib_rules: add extack support 2018-04-23 10:21:24 -04:00
dns_resolver KEYS: DNS: limit the length of option strings 2018-04-17 15:17:41 -04:00
dsa net: dsa: Plug in PHYLINK support 2018-05-11 12:03:06 -04:00
ethernet net: core: rework basic flow dissection helper 2018-05-08 00:02:36 -04:00
hsr net: hsr: Convert timers to use timer_setup() 2017-10-25 13:00:27 +09:00
ieee802154 net: ieee802154: 6lowpan: fix frag reassembly 2018-04-23 20:56:24 +02:00
ife net: sched: ife: check on metadata length 2018-04-22 21:12:00 -04:00
ipv4 tcp: add SACK compression 2018-05-18 11:40:27 -04:00
ipv6 Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next 2018-05-16 22:47:11 -04:00
iucv Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2018-03-23 11:31:58 -04:00
kcm net: Drop pernet_operations::async 2018-03-27 13:18:09 -04:00
key af_key: Always verify length of provided sadb_key 2018-04-09 07:06:38 +02:00
l2tp l2tp: consistent reference counting in procfs and debufs 2018-04-27 11:06:35 -04:00
l3mdev
lapb treewide: Remove TIMER_FUNC_TYPE and TIMER_DATA_TYPE casts 2017-11-21 16:35:54 -08:00
llc llc: better deal with too small mtu 2018-05-08 00:11:40 -04:00
mac80211 mac80211: use timeout from the AddBA response instead of the request 2018-05-07 20:35:15 +02:00
mac802154 net/mac802154: disambiguate mac80215 vs mac802154 trace events 2018-03-28 22:55:18 +02:00
mpls net: Drop pernet_operations::async 2018-03-27 13:18:09 -04:00
ncsi net/ncsi: prevent a couple array underflows 2018-05-17 16:27:39 -04:00
netfilter Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf-next 2018-05-06 21:51:37 -04:00
netlabel netlabel: If PF_INET6, check sk_buff ip header version 2018-02-14 14:01:41 -05:00
netlink net/netlink: make sure the headers line up actual value output 2018-05-04 13:00:57 -04:00
netrom net: Use octal not symbolic permissions 2018-03-26 12:07:48 -04:00
nfc Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2018-02-19 18:46:11 -05:00
nsh nsh: fix infinite loop 2018-05-04 12:54:38 -04:00
openvswitch Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2018-05-11 20:53:22 -04:00
packet dev: packet: make packet_direct_xmit a common function 2018-05-03 15:55:24 -07:00
phonet net: Drop pernet_operations::async 2018-03-27 13:18:09 -04:00
psample MAINTAINERS: Update Yotam's E-mail 2017-11-01 12:19:03 +09:00
qrtr net: qrtr: Expose tunneling endpoint to user space 2018-04-27 15:06:10 -04:00
rds rds: do not leak kernel memory to user land 2018-05-03 11:26:14 -04:00
rfkill rfkill: gpio: fix memory leak in probe error path 2018-05-07 15:01:40 +02:00
rose net: Use octal not symbolic permissions 2018-03-26 12:07:48 -04:00
rxrpc rxrpc: Trace UDP transmission failure 2018-05-10 23:26:01 +01:00
sched pfifo_fast: drop unneeded additional lock on dequeue 2018-05-17 12:46:54 -04:00
sctp sctp: checkpatch fixups 2018-05-14 23:15:27 -04:00
smc net/smc: init conn.tx_work & conn.send_lock sooner 2018-05-17 16:25:35 -04:00
strparser strparser: Do not call mod_delayed_work with a timeout of LONG_MAX 2018-04-22 21:09:16 -04:00
sunrpc NFS client fixes for Linux 4.17-rc4 2018-05-11 13:56:43 -07:00
switchdev net: bridge: Add/del switchdev object on host join/leave 2017-11-10 13:41:40 +09:00
tipc Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2018-05-11 20:53:22 -04:00
tls Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2018-05-11 20:53:22 -04:00
unix af_unix: remove redundant lockdep class 2018-04-04 11:13:40 -04:00
vmw_vsock VSOCK: make af_vsock.ko removable again 2018-04-17 09:44:30 -04:00
wimax License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
wireless nl80211: Free connkeys on external authentication failure 2018-04-20 09:58:03 +02:00
x25 net: Use octal not symbolic permissions 2018-03-26 12:07:48 -04:00
xdp xsk: fix 64-bit division 2018-05-09 18:12:21 +02:00
xfrm Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2018-05-11 20:53:22 -04:00
Kconfig Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next 2018-05-07 23:35:08 -04:00
Makefile xsk: add user memory registration support sockopt 2018-05-03 15:55:23 -07:00
compat.c net: support compat 64-bit time in {s,g}etsockopt 2018-04-27 19:46:06 -04:00
socket.c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial 2018-04-05 11:56:35 -07:00
sysctl_net.c net: Drop pernet_operations::async 2018-03-27 13:18:09 -04:00