UDP send with MSG_MORE takes a slightly different path than the
lockless fast path.
For completeness, add coverage to this case too.
Pass MSG_MORE on the initial sendmsg, then follow up with a zero byte
write to unplug the cork.
Unrelated: also add two missing endlines in usage().
Signed-off-by: Willem de Bruijn <willemb@google.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20250307033620.411611-4-willemdebruijn.kernel@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Expand IPV6_TCLASS to also cover IP_TOS.
Expand IPV6_HOPLIMIT to also cover IP_TTL.
Expand csmg_sender.c to allow setting IPv4 setsockopts.
Also rename struct v6 to cmsg to match its expanded scope.
Don't bother updating all occurrences of tclass and hoplimit.
Rename cmsg_ipv6.sh to cmsg_ip.sh to match the expanded scope.
Be careful around the subtle API difference between TCLASS and TOS.
IP_TOS includes ECN bits. Add a test to verify that these are masked
when making routing decisions.
Diff is more concise with --word-diff
Signed-off-by: Willem de Bruijn <willemb@google.com>
Link: https://patch.msgid.link/20250225022431.2083926-3-willemdebruijn.kernel@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
