selftests/xsk: Add support for zero copy testing

Introduce new mode to xdpxceiver responsible for testing AF_XDP zero
copy support of driver that serves underlying physical device. When
setting up test suite, determine whether driver has ZC support or not by
trying to bind XSK ZC socket to the interface. If it succeeded,
interpret it as ZC support being in place and do softirq and busy poll
tests for zero copy mode.

Note that Rx dropped tests are skipped since ZC path is not touching
rx_dropped stat at all.

Signed-off-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Magnus Karlsson <magnus.karlsson@intel.com>
Link: https://lore.kernel.org/bpf/20220901114813.16275-7-maciej.fijalkowski@intel.com

1 files changed, 2 insertions, 0 deletions

diff --git a/tools/testing/selftests/bpf/xskxceiver.h b/tools/testing/selftests/bpf/xskxceiver.h
index 11f017785986..edb76d2def9f 100644
--- a/tools/testing/selftests/bpf/xskxceiver.h
+++ b/tools/testing/selftests/bpf/xskxceiver.h
@@ -62,6 +62,7 @@
 enum test_mode {
 	TEST_MODE_SKB,
 	TEST_MODE_DRV,
+	TEST_MODE_ZC,
 	TEST_MODE_MAX
 };
 
@@ -167,6 +168,7 @@ struct test_spec {
 	u16 current_step;
 	u16 nb_sockets;
 	bool fail;
+	enum test_mode mode;
 	char name[MAX_TEST_NAME_SIZE];
 };