linux/net/ipv4
Eric Dumazet f921a4a5bf tcp: tsq: relax tcp_small_queue_check() when rtx queue contains a single skb
In commit 75eefc6c59 ("tcp: tsq: add a shortcut in tcp_small_queue_check()")
we allowed to send an skb regardless of TSQ limits being hit if rtx queue
was empty or had a single skb, in order to better fill the pipe
when/if TX completions were slow.

Then later, commit 75c119afe1 ("tcp: implement rb-tree based
retransmit queue") accidentally removed the special case for
one skb in rtx queue.

Stefan Wahren reported a regression in single TCP flow throughput
using a 100Mbit fec link, starting from commit 65466904b0 ("tcp: adjust
TSO packet sizes based on min_rtt"). This last commit only made the
regression more visible, because it locked the TCP flow on a particular
behavior where TSQ prevented two skbs being pushed downstream,
adding silences on the wire between each TSO packet.

Many thanks to Stefan for his invaluable help !

Fixes: 75c119afe1 ("tcp: implement rb-tree based retransmit queue")
Link: https://lore.kernel.org/netdev/7f31ddc8-9971-495e-a1f6-819df542e0af@gmx.net/
Reported-by: Stefan Wahren <wahrenst@gmx.net>
Tested-by: Stefan Wahren <wahrenst@gmx.net>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Neal Cardwell <ncardwell@google.com>
Link: https://lore.kernel.org/r/20231017124526.4060202-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-10-18 18:06:36 -07:00
..
bpfilter net: Use umd_cleanup_helper() 2023-05-31 13:06:57 +02:00
netfilter inet: move inet->nodefrag to inet->inet_flags 2023-08-16 11:09:17 +01:00
af_inet.c tcp: allow again tcp_disconnect() when threads are waiting 2023-10-13 16:49:32 -07:00
ah4.c net: ipv4: Remove completion function scaffolding 2023-02-13 18:35:15 +08:00
arp.c neighbour: annotate lockless accesses to n->nud_state 2023-03-15 00:37:32 -07:00
bpf_tcp_ca.c bpf: Drop useless btf_vmlinux in bpf_tcp_ca 2023-07-18 17:31:10 -07:00
cipso_ipv4.c inet: move inet->is_icsk to inet->inet_flags 2023-08-16 11:09:17 +01:00
datagram.c ipv4: fix data-races around inet->inet_id 2023-08-20 11:40:49 +01:00
devinet.c net: ipv4: fix one memleak in __inet_del_ifa() 2023-09-08 08:02:17 +01:00
esp4_offload.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2023-06-22 18:40:38 -07:00
esp4.c net: ipv4: fix return value check in esp_remove_trailer 2023-10-10 09:55:35 +02:00
fib_frontend.c ipv4: Fix incorrect table ID in IOCTL path 2023-03-16 17:26:31 -07:00
fib_lookup.h
fib_notifier.c
fib_rules.c ipv4: remove unnecessary type castings 2022-04-30 15:12:58 +01:00
fib_semantics.c ipv4/fib: send notify when delete source address routes 2023-10-03 09:00:40 +02:00
fib_trie.c ipv4/fib: send notify when delete source address routes 2023-10-03 09:00:40 +02:00
fou_bpf.c bpf,fou: Add bpf_skb_{set,get}_fou_encap kfuncs 2023-04-12 16:40:39 -07:00
fou_core.c bpf,fou: Add bpf_skb_{set,get}_fou_encap kfuncs 2023-04-12 16:40:39 -07:00
fou_nl.c net: ynl: prefix uAPI header include with uapi/ 2023-05-26 10:30:14 +01:00
fou_nl.h net: ynl: prefix uAPI header include with uapi/ 2023-05-26 10:30:14 +01:00
gre_demux.c
gre_offload.c net: move gso declarations and functions to their own files 2023-06-10 00:11:41 -07:00
icmp.c icmp: guard against too small mtu 2023-03-31 21:37:06 -07:00
igmp.c igmp: limit igmpv3_newpack() packet size to IP_MAX_MTU 2023-09-05 17:49:40 +01:00
inet_connection_sock.c tcp: allow again tcp_disconnect() when threads are waiting 2023-10-13 16:49:32 -07:00
inet_diag.c inet: move inet->defer_connect to inet->inet_flags 2023-08-16 11:09:18 +01:00
inet_fragment.c net: dropreason: add SKB_DROP_REASON_FRAG_REASM_TIMEOUT 2022-10-31 20:14:27 -07:00
inet_hashtables.c tcp: Fix listen() warning with v4-mapped-v6 address. 2023-10-13 10:01:49 -07:00
inet_timewait_sock.c inet: move inet->transparent to inet->inet_flags 2023-08-16 11:09:17 +01:00
inetpeer.c inetpeer: Fix data-races around sysctl. 2022-07-08 12:10:33 +01:00
ip_forward.c net: ipv4, ipv6: fix IPSTATS_MIB_OUTOCTETS increment duplicated 2023-08-30 09:44:09 +01:00
ip_fragment.c networking: Update to register_net_sysctl_sz 2023-08-15 15:26:18 -07:00
ip_gre.c ipv4: ip_gre: fix return value check in erspan_xmit() 2023-07-19 12:27:09 +01:00
ip_input.c ipv4: ignore dst hint for multipath routes 2023-09-01 08:11:51 +01:00
ip_options.c
ip_output.c net: annotate data-races around sk->sk_tsflags 2023-09-01 07:27:33 +01:00
ip_sockglue.c net: annotate data-races around sk->sk_tsflags 2023-09-01 07:27:33 +01:00
ip_tunnel_core.c tunnels: fix kasan splat when generating ipv4 pmtu error 2023-08-04 18:24:52 -07:00
ip_tunnel.c bpf-next-for-netdev 2023-04-13 16:43:38 -07:00
ip_vti.c ip_vti: fix potential slab-use-after-free in decode_session6 2023-07-11 11:06:08 +02:00
ipcomp.c xfrm: ipcomp: add extack to ipcomp{4,6}_init_state 2022-09-29 07:18:00 +02:00
ipconfig.c net: ipconfig: move ic_nameservers_fallback into #ifdef block 2023-05-22 11:17:55 +01:00
ipip.c ipip,ip_tunnel,sit: Add FOU support for externally controlled ipip devices 2023-04-12 16:40:39 -07:00
ipmr_base.c ipmr: adopt rcu_read_lock() in mr_dump() 2022-06-24 11:34:38 +01:00
ipmr.c net: ipv4, ipv6: fix IPSTATS_MIB_OUTOCTETS increment duplicated 2023-08-30 09:44:09 +01:00
Kconfig tcp: configurable source port perturb table size 2022-11-16 13:02:04 +00:00
Makefile bpf,fou: Add bpf_skb_{set,get}_fou_encap kfuncs 2023-04-12 16:40:39 -07:00
metrics.c ipv4: prevent potential spectre v1 gadget in ip_metrics_convert() 2023-01-23 21:37:25 -08:00
netfilter.c netfilter: Use l3mdev flow key when re-routing mangled packets 2022-05-16 13:03:29 +02:00
netlink.c
nexthop.c nexthop: Do not increment dump sentinel at the end of the dump 2023-08-15 18:54:53 -07:00
ping.c inet: move inet->recverr to inet->inet_flags 2023-08-16 11:09:17 +01:00
proc.c icmp: Add counters for rate limits 2023-01-26 10:52:18 +01:00
protocol.c
raw_diag.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2023-04-06 12:01:20 -07:00
raw.c inet: move inet->hdrincl to inet->inet_flags 2023-08-16 11:09:17 +01:00
route.c ipv4: Set offload_failed flag in fibmatch results 2023-10-04 11:39:36 -07:00
syncookies.c tcp: Set route scope properly in cookie_v4_check(). 2023-06-06 21:13:03 -07:00
sysctl_net_ipv4.c networking: Update to register_net_sysctl_sz 2023-08-15 15:26:18 -07:00
tcp_bbr.c bpf: Add __bpf_kfunc tag to all kfuncs 2023-02-02 00:25:14 +01:00
tcp_bic.c
tcp_bpf.c tcp: allow again tcp_disconnect() when threads are waiting 2023-10-13 16:49:32 -07:00
tcp_cdg.c Random number generator fixes for Linux 6.1-rc1. 2022-10-16 15:27:07 -07:00
tcp_cong.c net: Update an existing TCP congestion control algorithm. 2023-03-22 22:53:00 -07:00
tcp_cubic.c bpf: Add __bpf_kfunc tag to all kfuncs 2023-02-02 00:25:14 +01:00
tcp_dctcp.c bpf: Add __bpf_kfunc tag to all kfuncs 2023-02-02 00:25:14 +01:00
tcp_dctcp.h
tcp_diag.c tcp: Access &tcp_hashinfo via net. 2022-09-20 10:21:49 -07:00
tcp_fastopen.c inet: move inet->defer_connect to inet->inet_flags 2023-08-16 11:09:18 +01:00
tcp_highspeed.c
tcp_htcp.c
tcp_hybla.c
tcp_illinois.c
tcp_input.c tcp: fix delayed ACKs for MSS boundary condition 2023-10-04 15:34:18 -07:00
tcp_ipv4.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2023-08-24 10:51:39 -07:00
tcp_lp.c
tcp_metrics.c tcp_metrics: hash table allocation cleanup 2023-08-04 15:33:39 -07:00
tcp_minisocks.c inet: move inet->transparent to inet->inet_flags 2023-08-16 11:09:17 +01:00
tcp_nv.c
tcp_offload.c net: move gso declarations and functions to their own files 2023-06-10 00:11:41 -07:00
tcp_output.c tcp: tsq: relax tcp_small_queue_check() when rtx queue contains a single skb 2023-10-18 18:06:36 -07:00
tcp_plb.c prandom: remove prandom_u32_max() 2022-12-20 03:13:45 +01:00
tcp_rate.c
tcp_recovery.c tcp: fix excessive TLP and RACK timeouts from HZ rounding 2023-10-17 17:25:42 -07:00
tcp_scalable.c
tcp_timer.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2023-08-18 12:44:56 -07:00
tcp_ulp.c net/ulp: use consistent error code when blocking ULP 2023-01-19 09:26:16 -08:00
tcp_vegas.c
tcp_vegas.h
tcp_veno.c
tcp_westwood.c
tcp_yeah.c
tcp.c tcp: allow again tcp_disconnect() when threads are waiting 2023-10-13 16:49:32 -07:00
tunnel4.c
udp_bpf.c bpf, sockmap: Fix an infinite loop error when len is 0 in tcp_bpf_recvmsg_parser() 2023-03-03 17:25:15 +01:00
udp_diag.c udp: Access &udp_table via net. 2022-11-16 09:43:35 +00:00
udp_impl.h sock: Remove ->sendpage*() in favour of sendmsg(MSG_SPLICE_PAGES) 2023-06-24 15:50:13 -07:00
udp_offload.c net: gro: fix misuse of CB in udp socket lookup 2023-07-29 17:10:27 +01:00
udp_tunnel_core.c inet: move inet->mc_loop to inet->inet_frags 2023-08-16 11:09:17 +01:00
udp_tunnel_nic.c udp_tunnel: Add checks for nla_nest_start() in __udp_tunnel_nic_dump_write() 2022-11-29 08:44:24 -08:00
udp_tunnel_stub.c
udp.c net: annotate data-races around sk->sk_forward_alloc 2023-09-01 07:27:33 +01:00
udplite.c sock: Remove ->sendpage*() in favour of sendmsg(MSG_SPLICE_PAGES) 2023-06-24 15:50:13 -07:00
xfrm4_input.c xfrm: fix inbound ipv4/udp/esp packets to UDPv6 dualstack sockets 2023-06-09 08:16:34 +02:00
xfrm4_output.c
xfrm4_policy.c sysctl-6.6-rc1 2023-08-29 17:39:15 -07:00
xfrm4_protocol.c net: xfrm: unexport __init-annotated xfrm4_protocol_init() 2022-06-08 10:10:13 -07:00
xfrm4_state.c
xfrm4_tunnel.c xfrm: tunnel: add extack to ipip_init_state, xfrm6_tunnel_init_state 2022-09-29 07:18:00 +02:00