From: Willem de Bruijn <will...@google.com> Enable MSG_ZEROCOPY for udp sockets
Patch 1/3 is the main patch, a rework of RFC patch http://patchwork.ozlabs.org/patch/899630/ more details in the patch commit message Patch 2/3 is an optimization to remove a branch from the UDP hot path and refcount_inc/refcount_dec_and_test pair when zerocopy is used. This used to be included in the first patch in v2. Patch 3/3 runs the already existing udp zerocopy tests as part of kselftest See also recent Linux Plumbers presentation https://linuxplumbersconf.org/event/2/contributions/106/attachments/104/128/willemdebruijn-lpc2018-udpgso-presentation-20181113.pdf 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 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 Willem de Bruijn (3): udp: msg_zerocopy udp: elide zerocopy operation in hot path selftests: extend zerocopy tests to udp include/linux/skbuff.h | 13 +++++--- net/core/skbuff.c | 15 ++++++--- net/core/sock.c | 5 ++- net/ipv4/ip_output.c | 37 ++++++++++++++++----- net/ipv4/tcp.c | 2 +- net/ipv6/ip6_output.c | 37 ++++++++++++++++----- tools/testing/selftests/net/msg_zerocopy.c | 3 +- tools/testing/selftests/net/msg_zerocopy.sh | 2 ++ tools/testing/selftests/net/udpgso_bench.sh | 3 ++ 9 files changed, 90 insertions(+), 27 deletions(-) -- 2.20.0.rc1.387.gf8505762e3-goog
