android_kernel_samsung_sm8650/net/ipv4
Kuniyuki Iwashima edc12f032a tcp: Save unnecessary inet_twsk_purge() calls.
While destroying netns, we call inet_twsk_purge() in tcp_sk_exit_batch()
and tcpv6_net_exit_batch() for AF_INET and AF_INET6.  These commands
trigger the kernel to walk through the potentially big ehash twice even
though the netns has no TIME_WAIT sockets.

  # ip netns add test
  # ip netns del test

  or

  # unshare -n /bin/true >/dev/null

When tw_refcount is 1, we need not call inet_twsk_purge() at least
for the net.  We can save such unneeded iterations if all netns in
net_exit_list have no TIME_WAIT sockets.  This change eliminates
the tax by the additional unshare() described in the next patch to
guarantee the per-netns ehash size.

Tested:

  # mount -t debugfs none /sys/kernel/debug/
  # echo cleanup_net > /sys/kernel/debug/tracing/set_ftrace_filter
  # echo inet_twsk_purge >> /sys/kernel/debug/tracing/set_ftrace_filter
  # echo function > /sys/kernel/debug/tracing/current_tracer
  # cat ./add_del_unshare.sh
  for i in `seq 1 40`
  do
      (for j in `seq 1 100` ; do  unshare -n /bin/true >/dev/null ; done) &
  done
  wait;
  # ./add_del_unshare.sh

Before the patch:

  # cat /sys/kernel/debug/tracing/trace_pipe
    kworker/u128:0-8       [031] ...1.   174.162765: cleanup_net <-process_one_work
    kworker/u128:0-8       [031] ...1.   174.240796: inet_twsk_purge <-cleanup_net
    kworker/u128:0-8       [032] ...1.   174.244759: inet_twsk_purge <-tcp_sk_exit_batch
    kworker/u128:0-8       [034] ...1.   174.290861: cleanup_net <-process_one_work
    kworker/u128:0-8       [039] ...1.   175.245027: inet_twsk_purge <-cleanup_net
    kworker/u128:0-8       [046] ...1.   175.290541: inet_twsk_purge <-tcp_sk_exit_batch
    kworker/u128:0-8       [037] ...1.   175.321046: cleanup_net <-process_one_work
    kworker/u128:0-8       [024] ...1.   175.941633: inet_twsk_purge <-cleanup_net
    kworker/u128:0-8       [025] ...1.   176.242539: inet_twsk_purge <-tcp_sk_exit_batch

After:

  # cat /sys/kernel/debug/tracing/trace_pipe
    kworker/u128:0-8       [038] ...1.   428.116174: cleanup_net <-process_one_work
    kworker/u128:0-8       [038] ...1.   428.262532: cleanup_net <-process_one_work
    kworker/u128:0-8       [030] ...1.   429.292645: cleanup_net <-process_one_work

Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-09-20 10:21:50 -07:00
..
bpfilter net: Revert "net: optimize the sockptr_t for unified kernel/user address spaces" 2020-08-10 12:06:44 -07:00
netfilter tcp: Access &tcp_hashinfo via net. 2022-09-20 10:21:49 -07:00
af_inet.c tcp: Set NULL to sk->sk_prot->h.hashinfo. 2022-09-20 10:21:49 -07:00
ah4.c net: ipv4: fix clang -Wformat warnings 2022-07-12 12:58:53 +02:00
arp.c ipv4: move from strlcpy with unused retval to strscpy 2022-08-22 17:59:37 -07:00
bpf_tcp_ca.c bpf: Switch to new kfunc flags infrastructure 2022-07-21 20:59:42 -07:00
cipso_ipv4.c cipso: Fix data-races around sysctl. 2022-07-08 12:10:33 +01:00
datagram.c net-next: Fix IP_UNICAST_IF option behavior for connected sockets 2022-08-31 19:51:06 -07:00
devinet.c net: Fix data-races around sysctl_devconf_inherit_init_net. 2022-08-24 13:46:58 +01:00
esp4_offload.c net: Fix esp GSO on inter address family tunnels. 2022-03-07 13:14:04 +01:00
esp4.c tcp: Access &tcp_hashinfo via net. 2022-09-20 10:21:49 -07:00
fib_frontend.c ip: fix triggering of 'icmp redirect' 2022-08-31 19:50:36 -07:00
fib_lookup.h Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2022-02-17 11:44:20 -08:00
fib_notifier.c net: ipv4: remove superfluous header files from fib_notifier.c 2021-09-28 17:32:56 -07:00
fib_rules.c ipv4: remove unnecessary type castings 2022-04-30 15:12:58 +01:00
fib_semantics.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2022-07-21 13:03:39 -07:00
fib_trie.c ipv4: Fix data-races around sysctl_fib_notify_on_flag_change. 2022-07-25 12:42:10 +01:00
fou.c genetlink: start to validate reserved header bytes 2022-08-29 12:47:15 +01:00
gre_demux.c net: Remove the member netns_ok 2021-05-17 15:29:35 -07:00
gre_offload.c net: gro: skb_gro_header helper function 2022-08-25 10:33:21 +02:00
icmp.c ip: Fix data-races around sysctl_ip_no_pmtu_disc. 2022-07-15 11:49:55 +01:00
igmp.c bpf: net: Change do_ip_getsockopt() to take the sockptr_t argument 2022-09-02 20:34:31 -07:00
inet_connection_sock.c tcp: Set NULL to sk->sk_prot->h.hashinfo. 2022-09-20 10:21:49 -07:00
inet_diag.c net: inet: Retire port only listening_hash 2022-05-12 16:52:18 -07:00
inet_fragment.c ipv4: remove unnecessary type castings 2022-04-30 15:12:58 +01:00
inet_hashtables.c tcp: Access &tcp_hashinfo via net. 2022-09-20 10:21:49 -07:00
inet_timewait_sock.c tcp: Don't allocate tcp_death_row outside of struct netns_ipv4. 2022-09-20 10:21:49 -07:00
inetpeer.c inetpeer: Fix data-races around sysctl. 2022-07-08 12:10:33 +01:00
ip_forward.c ip: Fix data-races around sysctl_ip_fwd_update_priority. 2022-07-15 11:49:55 +01:00
ip_fragment.c net: ip: Handle delivery_time in ip defrag 2022-03-03 14:38:48 +00:00
ip_gre.c ip_tunnel: Respect tunnel key's "flow_flags" in IP tunnels 2022-08-18 21:18:28 +02:00
ip_input.c tcp/udp: Make early_demux back namespacified. 2022-07-15 18:50:35 -07:00
ip_options.c ipv4: drop fragmentation code from ip_options_build() 2022-01-29 17:53:07 +00:00
ip_output.c net: unify alloclen calculation for paged requests 2022-08-30 12:02:55 +02:00
ip_sockglue.c Merge https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next 2022-09-06 23:21:18 +02:00
ip_tunnel_core.c tunnels: do not assume mac header is set in skb_tunnel_check_pmtu() 2022-06-27 11:50:30 +01:00
ip_tunnel.c ip_tunnel: Respect tunnel key's "flow_flags" in IP tunnels 2022-08-18 21:18:28 +02:00
ip_vti.c ip: use dev_addr_set() in tunnels 2021-10-13 09:41:37 -07:00
ipcomp.c Networking changes for 5.14. 2021-06-30 15:51:09 -07:00
ipconfig.c Driver core / kernfs changes for 6.0-rc1 2022-08-04 11:31:20 -07:00
ipip.c ip: use dev_addr_set() in tunnels 2021-10-13 09:41:37 -07:00
ipmr_base.c ipmr: adopt rcu_read_lock() in mr_dump() 2022-06-24 11:34:38 +01:00
ipmr.c bpf: net: Change do_ip_getsockopt() to take the sockptr_t argument 2022-09-02 20:34:31 -07:00
Kconfig fou: Remove XRFM from NET_FOU Kconfig 2022-04-12 14:56:33 -07:00
Makefile bpf: Clean up sockmap related Kconfigs 2021-02-26 12:28:03 -08:00
metrics.c treewide: rename nla_strlcpy to nla_strscpy. 2020-11-16 08:08:54 -08:00
netfilter.c netfilter: Use l3mdev flow key when re-routing mangled packets 2022-05-16 13:03:29 +02:00
netlink.c treewide: Add SPDX license identifier for missed files 2019-05-21 10:50:45 +02:00
nexthop.c nexthop: Fix data-races around nexthop_compat_mode. 2022-07-13 12:56:50 +01:00
ping.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2022-06-23 12:33:24 -07:00
proc.c tcp: Don't allocate tcp_death_row outside of struct netns_ipv4. 2022-09-20 10:21:49 -07:00
protocol.c net: Remove the member netns_ok 2021-05-17 15:29:35 -07:00
raw_diag.c raw: complete rcu conversion 2022-06-21 11:38:29 +02:00
raw.c raw: fix a typo in raw_icmp_error() 2022-06-24 22:48:33 -07:00
route.c Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/klassert/ipsec-next 2022-07-25 13:25:39 +01:00
syncookies.c tcp: Fix data-races around sysctl knobs related to SYN option. 2022-07-20 10:14:49 +01:00
sysctl_net_ipv4.c tcp: Don't allocate tcp_death_row outside of struct netns_ipv4. 2022-09-20 10:21:49 -07:00
tcp_bbr.c bpf: Switch to new kfunc flags infrastructure 2022-07-21 20:59:42 -07:00
tcp_bic.c tcp: add accessors to read/set tp->snd_cwnd 2022-04-06 12:05:41 -07:00
tcp_bpf.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2022-06-23 12:33:24 -07:00
tcp_cdg.c tcp: add accessors to read/set tp->snd_cwnd 2022-04-06 12:05:41 -07:00
tcp_cong.c tcp: Add tracepoint for tcp_set_ca_state 2022-04-07 20:33:15 -07:00
tcp_cubic.c bpf: Switch to new kfunc flags infrastructure 2022-07-21 20:59:42 -07:00
tcp_dctcp.c bpf: Switch to new kfunc flags infrastructure 2022-07-21 20:59:42 -07:00
tcp_dctcp.h tcp: refactor DCTCP ECN ACK handling 2018-10-10 22:26:00 -07:00
tcp_diag.c tcp: Access &tcp_hashinfo via net. 2022-09-20 10:21:49 -07:00
tcp_fastopen.c tcp: Make SYN ACK RTO tunable by BPF programs with TFO 2022-08-17 10:19:22 +01:00
tcp_highspeed.c tcp: add accessors to read/set tp->snd_cwnd 2022-04-06 12:05:41 -07:00
tcp_htcp.c tcp: add accessors to read/set tp->snd_cwnd 2022-04-06 12:05:41 -07:00
tcp_hybla.c tcp: add accessors to read/set tp->snd_cwnd 2022-04-06 12:05:41 -07:00
tcp_illinois.c tcp: add accessors to read/set tp->snd_cwnd 2022-04-06 12:05:41 -07:00
tcp_input.c tcp: fix early ETIMEDOUT after spurious non-SACK RTO 2022-09-06 11:06:31 +02:00
tcp_ipv4.c tcp: Save unnecessary inet_twsk_purge() calls. 2022-09-20 10:21:50 -07:00
tcp_lp.c tcp: add accessors to read/set tp->snd_cwnd 2022-04-06 12:05:41 -07:00
tcp_metrics.c genetlink: start to validate reserved header bytes 2022-08-29 12:47:15 +01:00
tcp_minisocks.c tcp: Save unnecessary inet_twsk_purge() calls. 2022-09-20 10:21:50 -07:00
tcp_nv.c tcp: add accessors to read/set tp->snd_cwnd 2022-04-06 12:05:41 -07:00
tcp_offload.c net: gro: skb_gro_header helper function 2022-08-25 10:33:21 +02:00
tcp_output.c net: Fix data-races around sysctl_[rw]mem_(max|default). 2022-08-24 13:46:57 +01:00
tcp_rate.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2022-04-28 13:02:01 -07:00
tcp_recovery.c tcp: Fix data-races around sysctl_tcp_recovery. 2022-07-20 10:14:50 +01:00
tcp_scalable.c tcp: add accessors to read/set tp->snd_cwnd 2022-04-06 12:05:41 -07:00
tcp_timer.c tcp: Make SYN ACK RTO tunable by BPF programs with TFO 2022-08-17 10:19:22 +01:00
tcp_ulp.c bpf: sockmap: Only check ULP for TCP sockets 2020-03-09 22:34:58 +01:00
tcp_vegas.c tcp: add accessors to read/set tp->snd_cwnd 2022-04-06 12:05:41 -07:00
tcp_vegas.h
tcp_veno.c tcp: add accessors to read/set tp->snd_cwnd 2022-04-06 12:05:41 -07:00
tcp_westwood.c tcp: add accessors to read/set tp->snd_cwnd 2022-04-06 12:05:41 -07:00
tcp_yeah.c tcp: add accessors to read/set tp->snd_cwnd 2022-04-06 12:05:41 -07:00
tcp.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2022-09-08 18:38:30 +02:00
tunnel4.c net: Remove the member netns_ok 2021-05-17 15:29:35 -07:00
udp_bpf.c net: remove noblock parameter from recvmsg() entities 2022-04-12 15:00:25 +02:00
udp_diag.c net: Use nlmsg_unicast() instead of netlink_unicast() 2021-07-13 09:28:29 -07:00
udp_impl.h net: remove noblock parameter from recvmsg() entities 2022-04-12 15:00:25 +02:00
udp_offload.c gro: remove rcu_read_lock/rcu_read_unlock from gro_complete handlers 2021-11-24 17:21:42 -08:00
udp_tunnel_core.c rxrpc: Fix ICMP/ICMP6 error handling 2022-09-01 11:42:12 +01:00
udp_tunnel_nic.c udp_tunnel: Fix end of loop test in udp_tunnel_nic_unregister() 2022-02-23 12:35:00 +00:00
udp_tunnel_stub.c udp_tunnel: add central NIC RX port offload infrastructure 2020-07-10 13:54:00 -07:00
udp.c rxrpc: Fix ICMP/ICMP6 error handling 2022-09-01 11:42:12 +01:00
udplite.c net: add per_cpu_fw_alloc field to struct proto 2022-06-10 16:21:26 -07:00
xfrm4_input.c xfrm: state: remove extract_input indirection from xfrm_state_afinfo 2020-05-06 09:40:08 +02:00
xfrm4_output.c xfrm: fix unused variable warning if CONFIG_NETFILTER=n 2020-05-11 15:12:27 +02:00
xfrm4_policy.c net: rename reference+tracking helpers 2022-06-09 21:52:55 -07:00
xfrm4_protocol.c net: xfrm: unexport __init-annotated xfrm4_protocol_init() 2022-06-08 10:10:13 -07:00
xfrm4_state.c xfrm: remove output_finish indirection from xfrm_state_afinfo 2020-05-06 09:40:08 +02:00
xfrm4_tunnel.c net/ipv4/xfrm4_tunnel.c: remove superfluous header files from xfrm4_tunnel.c 2021-09-23 10:10:00 +02:00