linux/net/core
Willem de Bruijn b5947e5d1e udp: msg_zerocopy
Extend zerocopy to udp sockets. Allow setting sockopt SO_ZEROCOPY and
interpret flag MSG_ZEROCOPY.

This patch was previously part of the zerocopy RFC patchsets. Zerocopy
is not effective at small MTU. With segmentation offload building
larger datagrams, the benefit of page flipping outweights the cost of
generating a completion notification.

tools/testing/selftests/net/msg_zerocopy.sh after applying follow-on
test patch and making skb_orphan_frags_rx same as skb_orphan_frags:

    ipv4 udp -t 1
    tx=191312 (11938 MB) txc=0 zc=n
    rx=191312 (11938 MB)
    ipv4 udp -z -t 1
    tx=304507 (19002 MB) txc=304507 zc=y
    rx=304507 (19002 MB)
    ok
    ipv6 udp -t 1
    tx=174485 (10888 MB) txc=0 zc=n
    rx=174485 (10888 MB)
    ipv6 udp -z -t 1
    tx=294801 (18396 MB) txc=294801 zc=y
    rx=294801 (18396 MB)
    ok

Changes
  v1 -> v2
    - Fixup reverse christmas tree violation
  v2 -> v3
    - Split refcount avoidance optimization into separate patch
      - Fix refcount leak on error in fragmented case
        (thanks to Paolo Abeni for pointing this one out!)
      - Fix refcount inc on zero
      - Test sock_flag SOCK_ZEROCOPY directly in __ip_append_data.
        This is needed since commit 5cf4a8532c ("tcp: really ignore
	MSG_ZEROCOPY if no SO_ZEROCOPY") did the same for tcp.

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
..
datagram.c net: dump more useful information in netdev_rx_csum_fault() 2018-11-15 11:37:04 -08:00
dev_addr_lists.c net: core: dev_addr_lists: add auxiliary func to handle reference address updates 2018-11-08 20:30:57 -08:00
dev_ioctl.c net: remove redundant input checks in SIOCSIFTXQLEN case of dev_ifsioc 2018-07-24 11:36:15 -07:00
dev.c net: Add trace events for all receive exit points 2018-11-30 13:23:25 -08:00
devlink.c devlink: Add 'fw_load_policy' generic parameter 2018-12-03 13:55:43 -08:00
drop_monitor.c treewide: setup_timer() -> timer_setup() 2017-11-21 15:57:07 -08:00
dst_cache.c net: core: dst_cache_set_ip6: Rename 'addr' parameter to 'saddr' for consistency 2018-03-05 12:52:45 -05:00
dst.c netfilter: nf_tables: add tunnel support 2018-08-03 21:12:12 +02:00
ethtool.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2018-10-19 11:03:06 -07:00
failover.c net: Introduce generic failover module 2018-05-28 22:59:54 -04:00
fib_notifier.c net: Fix fib notifer to return errno 2018-03-29 14:10:30 -04:00
fib_rules.c net/fib_rules: Update fib_nl_dumprule for strict data checking 2018-10-08 10:39:05 -07:00
filter.c bpf: helper to pop data from messages 2018-11-28 22:07:57 +01:00
flow_dissector.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2018-11-11 17:57:54 -08:00
gen_estimator.c net: core: protect rate estimator statistics pointer with lock 2018-08-11 12:37:10 -07:00
gen_stats.c net/core: make function ___gnet_stats_copy_basic() static 2018-09-28 10:25:11 -07:00
gro_cells.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
hwbm.c
link_watch.c net: linkwatch: add check for netdevice being present to linkwatch_do_dev 2018-09-19 21:06:46 -07:00
lwt_bpf.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next 2018-08-07 11:02:05 -07:00
lwtunnel.c ipv6: sr: define core operations for seg6local lightweight tunnel 2017-08-07 14:16:22 -07:00
Makefile bpf, sockmap: convert to generic sk_msg interface 2018-10-15 12:23:19 -07:00
neighbour.c net/neigh: fix NULL deref in pneigh_dump_table() 2018-10-26 16:03:51 -07:00
net_namespace.c netns: enable to dump full nsid translation table 2018-11-27 16:20:20 -08:00
net-procfs.c proc: introduce proc_create_net{,_data} 2018-05-16 07:24:30 +02:00
net-sysfs.c net: allow to call netif_reset_xps_queues() under cpus_read_lock 2018-08-09 14:25:06 -07:00
net-sysfs.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
net-traces.c net/ipv6: Udate fib6_table_lookup tracepoint 2018-05-24 23:01:15 -04:00
netclassid_cgroup.c cgroup, netclassid: add a preemption point to write_classid 2018-10-23 12:58:17 -07:00
netevent.c
netpoll.c net: core: netpoll: Enable netconsole IPv6 link local address 2018-11-05 17:07:10 -08:00
netprio_cgroup.c net: remove duplicate includes 2017-12-13 13:18:46 -05:00
page_pool.c net/page_pool: Fix inconsistent lock state warning 2018-07-19 23:23:01 -07:00
pktgen.c pktgen: Fix fall-through annotation 2018-09-13 15:36:41 -07:00
ptp_classifier.c
request_sock.c
rtnetlink.c rtnetlink: avoid frame size warning in rtnl_newlink() 2018-11-30 13:33:34 -08:00
scm.c sched/headers: Prepare for new header dependencies before moving code to <linux/sched/user.h> 2017-03-02 08:42:29 +01:00
secure_seq.c infiniband: i40iw, nes: don't use wall time for TCP sequence numbers 2018-07-11 12:10:19 -06:00
skbuff.c udp: msg_zerocopy 2018-12-03 15:58:32 -08:00
skmsg.c tls: convert to generic sk_msg interface 2018-10-15 12:23:19 -07:00
sock_diag.c net: sock_diag: Fix spectre v1 gadget in __sock_diag_cmd() 2018-08-14 10:01:24 -07:00
sock_map.c bpf: skmsg, fix psock create on existing kcm/tls port 2018-10-20 00:40:45 +02:00
sock_reuseport.c sctp: add sock_reuseport for the sock in __sctp_hash_endpoint 2018-11-12 09:09:51 -08:00
sock.c udp: msg_zerocopy 2018-12-03 15:58:32 -08:00
stream.c vfs: do bulk POLL* -> EPOLL* replacement 2018-02-11 14:34:03 -08:00
sysctl_net_core.c bpf: add bpf_jit_limit knob to restrict unpriv allocations 2018-10-25 17:11:42 -07:00
timestamping.c
tso.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
utils.c net: Remove some unneeded semicolon 2018-08-04 13:05:39 -07:00
xdp.c xdp: remove redundant variable 'headroom' 2018-09-01 01:35:53 +02:00