linux-sg2042/net/ipv4
Willem de Bruijn 52900d2228 udp: elide zerocopy operation in hot path
With MSG_ZEROCOPY, each skb holds a reference to a struct ubuf_info.
Release of its last reference triggers a completion notification.

The TCP stack in tcp_sendmsg_locked holds an extra ref independent of
the skbs, because it can build, send and free skbs within its loop,
possibly reaching refcount zero and freeing the ubuf_info too soon.

The UDP stack currently also takes this extra ref, but does not need
it as all skbs are sent after return from __ip(6)_append_data.

Avoid the extra refcount_inc and refcount_dec_and_test, and generally
the sock_zerocopy_put in the common path, by passing the initial
reference to the first skb.

This approach is taken instead of initializing the refcount to 0, as
that would generate error "refcount_t: increment on 0" on the
next skb_zcopy_set.

Changes
  v3 -> v4
    - Move skb_zcopy_set below the only kfree_skb that might cause
      a premature uarg destroy before skb_zerocopy_put_abort
      - Move the entire skb_shinfo assignment block, to keep that
        cacheline access in one place

Signed-off-by: Willem de Bruijn <willemb@google.com>
Acked-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-12-03 15:58:32 -08:00
..
bpfilter bpfilter: remove trailing newline 2018-07-24 14:10:42 -07:00
netfilter netfilter: nat: fix double register in masquerade modules 2018-11-27 00:36:46 +01:00
Kconfig net: remove blank lines at end of file 2018-07-24 14:10:43 -07:00
Makefile bpf, sockmap: convert to generic sk_msg interface 2018-10-15 12:23:19 -07:00
af_inet.c inet: minor optimization for backlog setting in listen(2) 2018-11-07 22:31:07 -08:00
ah4.c net-ipv4: remove 2 always zero parameters from ipv4_redirect() 2018-09-26 20:30:55 -07:00
arp.c net: Evict neighbor entries on carrier down 2018-10-12 09:47:39 -07:00
cipso_ipv4.c net/ipv4: defensive cipso option parsing 2018-09-17 19:37:46 -07:00
datagram.c ipv4: Allow sending multicast packets on specific i/f using VRF socket 2018-10-02 22:28:17 -07:00
devinet.c net/{ipv4,ipv6}: Do not put target net if input nsid is invalid 2018-10-25 16:21:31 -07:00
esp4.c Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/klassert/ipsec-next 2018-10-01 22:31:17 -07:00
esp4_offload.c Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/klassert/ipsec-next 2018-07-27 09:33:37 -07:00
fib_frontend.c net: Don't return invalid table id error when dumping all families 2018-10-24 14:06:25 -07:00
fib_lookup.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
fib_notifier.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
fib_rules.c net: fib_rules: add extack support 2018-04-23 10:21:24 -04:00
fib_semantics.c net: Add extack argument to ip_fib_metrics_init 2018-11-06 15:00:45 -08:00
fib_trie.c net/ipv4: Plumb support for filtering route dumps 2018-10-16 00:13:12 -07:00
fou.c fou, fou6: ICMP error handlers for FoU and GUE 2018-11-08 17:13:08 -08:00
gre_demux.c net: Convert protocol error handlers from void to int 2018-11-08 17:13:08 -08:00
gre_offload.c Merge ra.kernel.org:/pub/scm/linux/kernel/git/davem/net 2018-07-03 10:29:26 +09:00
icmp.c net: Convert protocol error handlers from void to int 2018-11-08 17:13:08 -08:00
igmp.c ipv4/igmp: fix v1/v2 switchback timeout based on rfc3376, 8.12 2018-10-29 20:26:06 -07:00
inet_connection_sock.c inet: minor optimization for backlog setting in listen(2) 2018-11-07 22:31:07 -08:00
inet_diag.c sock_diag: request _diag module only when the family or proto has been registered 2018-03-12 11:03:42 -04:00
inet_fragment.c inet: frags: better deal with smp races 2018-11-08 18:40:30 -08:00
inet_hashtables.c net: ensure unbound stream socket to be chosen when not in a VRF 2018-11-07 16:12:38 -08:00
inet_timewait_sock.c soreuseport: initialise timewait reuseport field 2018-04-07 22:32:32 -04:00
inetpeer.c inetpeer: fix uninit-value in inet_getpeer 2018-04-09 10:57:35 -04:00
ip_forward.c net: ipv4: Control SKB reprioritization after forwarding 2018-08-01 09:52:30 -07:00
ip_fragment.c net: drop skb on failure in ip_check_defrag() 2018-11-01 13:55:30 -07:00
ip_gre.c net: Convert protocol error handlers from void to int 2018-11-08 17:13:08 -08:00
ip_input.c ip: factor out protocol delivery helper 2018-11-07 16:23:05 -08:00
ip_options.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
ip_output.c udp: elide zerocopy operation in hot path 2018-12-03 15:58:32 -08:00
ip_sockglue.c net: bpfilter: fix iptables failure if bpfilter_umh is disabled 2018-11-05 17:12:18 -08:00
ip_tunnel.c ip_tunnel: be careful when accessing the inner header 2018-09-24 12:27:04 -07:00
ip_tunnel_core.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2018-11-19 10:55:00 -08:00
ip_vti.c net-ipv4: remove 2 always zero parameters from ipv4_redirect() 2018-09-26 20:30:55 -07:00
ipcomp.c net-ipv4: remove 2 always zero parameters from ipv4_redirect() 2018-09-26 20:30:55 -07:00
ipconfig.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2018-06-06 18:39:49 -07:00
ipip.c net: Convert protocol error handlers from void to int 2018-11-08 17:13:08 -08:00
ipmr.c net: Don't return invalid table id error when dumping all families 2018-10-24 14:06:25 -07:00
ipmr_base.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2018-10-19 11:03:06 -07:00
metrics.c net: Add extack argument to ip_fib_metrics_init 2018-11-06 15:00:45 -08:00
netfilter.c netfilter: utils: move nf_ip_checksum* from ipv4 to utils 2018-07-16 17:51:48 +02:00
netlink.c ipv4: support sport, dport and ip_proto in RTM_GETROUTE 2018-05-23 15:14:12 -04:00
ping.c ipv4: Allow sending multicast packets on specific i/f using VRF socket 2018-10-02 22:28:17 -07:00
proc.c tcp: implement coalescing on backlog queue 2018-11-30 13:26:54 -08:00
protocol.c fou, fou6: ICMP error handlers for FoU and GUE 2018-11-08 17:13:08 -08:00
raw.c net/ipv4: Fix missing raw_init when CONFIG_PROC_FS is disabled 2018-11-27 20:58:02 -08:00
raw_diag.c net: ipv6: add second dif to raw socket lookups 2017-08-07 11:39:22 -07:00
route.c ipv4: Don't try to print ASCII of link level header in martian dumps. 2018-11-20 10:15:36 -08:00
syncookies.c tcp: provide earliest departure time in skb->tstamp 2018-09-21 19:37:59 -07:00
sysctl_net_ipv4.c net: provide a sysctl raw_l3mdev_accept for raw socket lookup with VRFs 2018-11-07 16:12:38 -08:00
tcp.c udp: elide zerocopy operation in hot path 2018-12-03 15:58:32 -08:00
tcp_bbr.c tcp_bbr: update comments to reflect pacing_margin_percent 2018-11-08 20:46:17 -08:00
tcp_bic.c tcp: consolidate congestion control undo functions 2017-08-06 21:25:10 -07:00
tcp_bpf.c bpf: helper to pop data from messages 2018-11-28 22:07:57 +01:00
tcp_cdg.c tcp: cdg: use tcp high resolution clock cache 2018-10-15 22:56:42 -07:00
tcp_cong.c tcp: Namespace-ify sysctl_tcp_default_congestion_control 2017-11-15 14:09:52 +09:00
tcp_cubic.c tcp: consolidate congestion control undo functions 2017-08-06 21:25:10 -07:00
tcp_dctcp.c tcp: refactor DCTCP ECN ACK handling 2018-10-10 22:26:00 -07:00
tcp_dctcp.h tcp: refactor DCTCP ECN ACK handling 2018-10-10 22:26:00 -07:00
tcp_diag.c net: sock: replace sk_state_load with inet_sk_state_load and remove sk_state_store 2017-12-20 14:00:25 -05:00
tcp_fastopen.c tcp: pause Fast Open globally after third consecutive timeout 2017-12-13 15:51:12 -05:00
tcp_highspeed.c tcp: consolidate congestion control undo functions 2017-08-06 21:25:10 -07:00
tcp_htcp.c tcp: fix cwnd undo in Reno and HTCP congestion controls 2017-08-06 21:25:10 -07:00
tcp_hybla.c
tcp_illinois.c net/tcp/illinois: replace broken algorithm reference link 2018-02-28 12:03:47 -05:00
tcp_input.c tcp: take care of compressed acks in tcp_add_reno_sack() 2018-11-30 13:26:53 -08:00
tcp_ipv4.c tcp: md5: add tcp_md5_needed jump label 2018-11-30 13:28:03 -08:00
tcp_lp.c tcp: switch TCP TS option (RFC 7323) to 1ms clock 2017-05-17 16:06:01 -04:00
tcp_metrics.c net: Drop pernet_operations::async 2018-03-27 13:18:09 -04:00
tcp_minisocks.c tcp: do not restart timewait timer on rst reception 2018-08-31 23:10:35 -07:00
tcp_nv.c tcp_nv: fix potential integer overflow in tcpnv_acked 2018-01-31 10:26:30 -05:00
tcp_offload.c tcp: Don't coalesce decrypted and encrypted SKBs 2018-07-16 00:12:09 -07:00
tcp_output.c tcp: md5: add tcp_md5_needed jump label 2018-11-30 13:28:03 -08:00
tcp_rate.c tcp: introduce tcp_skb_timestamp_us() helper 2018-09-21 19:37:59 -07:00
tcp_recovery.c tcp: introduce tcp_skb_timestamp_us() helper 2018-09-21 19:37:59 -07:00
tcp_scalable.c tcp: consolidate congestion control undo functions 2017-08-06 21:25:10 -07:00
tcp_timer.c tcp: address problems caused by EDT misshaps 2018-11-24 17:41:37 -08:00
tcp_ulp.c tcp, ulp: remove socket lock assertion on ULP cleanup 2018-10-16 12:38:41 -07:00
tcp_vegas.c tcp: fix under-evaluated ssthresh in TCP Vegas 2017-09-29 06:07:00 +01:00
tcp_vegas.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
tcp_veno.c tcp: consolidate congestion control undo functions 2017-08-06 21:25:10 -07:00
tcp_westwood.c tcp: Revert "tcp: remove CA_ACK_SLOWPATH" 2017-08-30 11:20:08 -07:00
tcp_yeah.c tcp: consolidate congestion control undo functions 2017-08-06 21:25:10 -07:00
tunnel4.c net: Convert protocol error handlers from void to int 2018-11-08 17:13:08 -08:00
udp.c udp: fix jump label misuse 2018-11-16 23:01:56 -08:00
udp_diag.c net: diag: document swapped src/dst in udp_dump_one. 2018-10-28 19:27:21 -07:00
udp_impl.h net: Convert protocol error handlers from void to int 2018-11-08 17:13:08 -08:00
udp_offload.c udp: implement GRO for plain UDP sockets. 2018-11-07 16:23:04 -08:00
udp_tunnel.c udp_tunnel: add config option to bind to a device 2018-12-03 14:15:26 -08:00
udplite.c net: Convert protocol error handlers from void to int 2018-11-08 17:13:08 -08:00
xfrm4_input.c xfrm: reset transport header back to network header after all input transforms ahave been applied 2018-09-04 10:26:30 +02:00
xfrm4_mode_beet.c networking: make skb_pull & friends return void pointers 2017-06-16 11:48:39 -04:00
xfrm4_mode_transport.c xfrm: reset transport header back to network header after all input transforms ahave been applied 2018-09-04 10:26:30 +02:00
xfrm4_mode_tunnel.c xfrm: Verify MAC header exists before overwriting eth_hdr(skb)->h_proto 2018-03-07 10:54:29 +01:00
xfrm4_output.c net: xfrm: use skb_gso_validate_network_len() to check gso sizes 2018-03-04 17:49:17 -05:00
xfrm4_policy.c net: Drop pernet_operations::async 2018-03-27 13:18:09 -04:00
xfrm4_protocol.c net: Convert protocol error handlers from void to int 2018-11-08 17:13:08 -08:00
xfrm4_state.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
xfrm4_tunnel.c