Zerocopy skbs are converted to regular copy skbs when data is queued
to a local socket. This happens in the existing test with a sender and
receiver communicating over a veth device.
Zerocopy skbs are sent without copying if egressing a device. Verify
that this behavior is maintained even in the common container setup
where data is forwarded over a veth to the physical device.
Update msg_zerocopy.sh to
1. Have a dummy network device to simulate a physical device.
2. Have forwarding enabled between veth and dummy.
3. Add a tx-only test that sends out dummy via the forwarding path.
4. Verify the exitcode of the sender, which signals zerocopy success.
As dummy drops all packets, this cannot be a TCP connection. Test
the new case with unconnected UDP only.
Update msg_zerocopy.c to
- Accept an argument whether send with zerocopy is expected.
- Return an exitcode whether behavior matched that expectation.
Signed-off-by: Willem de Bruijn <willemb@google.com>
Link: https://patch.msgid.link/20250630194312.1571410-3-willemdebruijn.kernel@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
/proc/sys/net/core/optmem_max is now per netns, change two tests
that were saving/changing/restoring its value on the parent netns.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Both msg_zerocopy and udpgso_bench have udp zerocopy variants.
Exercise these as part of the standard kselftest run.
With udp, msg_zerocopy has no control channel. Ensure that the
receiver exits after the sender by accounting for the initial
delay in starting them (in msg_zerocopy.sh).
Signed-off-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The existing msg_zerocopy test takes additional protocol arguments.
Add a variant that takes no arguments and runs all supported variants.
Call this from kselftest.
Signed-off-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Introduce regression test for msg_zerocopy feature. Send traffic from
one process to another with and without zerocopy.
Evaluate tcp, udp, raw and packet sockets, including variants
- udp: corking and corking with mixed copy/zerocopy calls
- raw: with and without hdrincl
- packet: at both raw and dgram level
Test on both ipv4 and ipv6, optionally with ethtool changes to
disable scatter-gather, tx checksum or tso offload. All of these
can affect zerocopy behavior.
The regression test can be run on a single machine if over a veth
pair. Then skb_orphan_frags_rx must be modified to be identical to
skb_orphan_frags to allow forwarding zerocopy locally.
The msg_zerocopy.sh script will setup the veth pair in network
namespaces and run all tests.
Signed-off-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
