Re: [PATCH net v2 2/2] selftests: drv-net: test XDP, HDS auto and the ioctl path

[Stanislav Fomichev <stfomichev@gmail.com>]

On 02/20, Jakub Kicinski wrote:
> Test XDP and HDS interaction. While at it add a test for using the IOCTL,
> as that turned out to be the real culprit.
> 
> Testing bnxt:
> 
>   # NETIF=eth0 ./ksft-net-drv/drivers/net/hds.py
>   KTAP version 1
>   1..12
>   ok 1 hds.get_hds
>   ok 2 hds.get_hds_thresh
>   ok 3 hds.set_hds_disable # SKIP disabling of HDS not supported by the device
>   ok 4 hds.set_hds_enable
>   ok 5 hds.set_hds_thresh_zero
>   ok 6 hds.set_hds_thresh_max
>   ok 7 hds.set_hds_thresh_gt
>   ok 8 hds.set_xdp
>   ok 9 hds.enabled_set_xdp
>   ok 10 hds.ioctl
>   ok 11 hds.ioctl_set_xdp
>   ok 12 hds.ioctl_enabled_set_xdp
>   # Totals: pass:11 fail:0 xfail:0 xpass:0 skip:1 error:0
> 
> and netdevsim:
> 
>   # ./ksft-net-drv/drivers/net/hds.py
>   KTAP version 1
>   1..12
>   ok 1 hds.get_hds
>   ok 2 hds.get_hds_thresh
>   ok 3 hds.set_hds_disable
>   ok 4 hds.set_hds_enable
>   ok 5 hds.set_hds_thresh_zero
>   ok 6 hds.set_hds_thresh_max
>   ok 7 hds.set_hds_thresh_gt
>   ok 8 hds.set_xdp
>   ok 9 hds.enabled_set_xdp
>   ok 10 hds.ioctl
>   ok 11 hds.ioctl_set_xdp
>   ok 12 hds.ioctl_enabled_set_xdp
>   # Totals: pass:12 fail:0 xfail:0 xpass:0 skip:0 error:0
> 
> Netdevsim needs a sane default for tx/rx ring size.
> 
> ethtool 6.11 is needed for the --disable-netlink option.
> 
> Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Acked-by: Stanislav Fomichev <sdf@fomichev.me>

> ---
> Since this is targeting net there is no cfg.rpath(),
> I'll follow up once in net-next.
> 
> v2:
>  - add the ioctl tests
>  - factor out some common logic
> 
> CC: shuah@kernel.org
> CC: hawk@kernel.org
> CC: petrm@nvidia.com
> CC: willemb@google.com
> CC: jstancek@redhat.com
> CC: linux-kselftest@vger.kernel.org
> ---
>  tools/testing/selftests/net/lib/Makefile      |   3 +
>  drivers/net/netdevsim/ethtool.c               |   2 +
>  .../testing/selftests/net/lib/xdp_dummy.bpf.c |  13 ++
>  tools/testing/selftests/drivers/net/hds.py    | 145 +++++++++++++++++-
>  4 files changed, 160 insertions(+), 3 deletions(-)
>  create mode 100644 tools/testing/selftests/net/lib/xdp_dummy.bpf.c
> 
> diff --git a/tools/testing/selftests/net/lib/Makefile b/tools/testing/selftests/net/lib/Makefile
> index bc6b6762baf3..c22623b9a2a5 100644
> --- a/tools/testing/selftests/net/lib/Makefile
> +++ b/tools/testing/selftests/net/lib/Makefile
> @@ -9,7 +9,10 @@ TEST_FILES := ../../../../../Documentation/netlink/specs
>  TEST_FILES += ../../../../net/ynl
>  
>  TEST_GEN_FILES += csum
> +TEST_GEN_FILES += $(patsubst %.c,%.o,$(wildcard *.bpf.c))
>  
>  TEST_INCLUDES := $(wildcard py/*.py sh/*.sh)
>  
>  include ../../lib.mk
> +
> +include ../bpf.mk
> diff --git a/drivers/net/netdevsim/ethtool.c b/drivers/net/netdevsim/ethtool.c
> index 5c80fbee7913..7ab358616e03 100644
> --- a/drivers/net/netdevsim/ethtool.c
> +++ b/drivers/net/netdevsim/ethtool.c
> @@ -184,9 +184,11 @@ static const struct ethtool_ops nsim_ethtool_ops = {
>  
>  static void nsim_ethtool_ring_init(struct netdevsim *ns)
>  {
> +	ns->ethtool.ring.rx_pending = 512;
>  	ns->ethtool.ring.rx_max_pending = 4096;
>  	ns->ethtool.ring.rx_jumbo_max_pending = 4096;
>  	ns->ethtool.ring.rx_mini_max_pending = 4096;
> +	ns->ethtool.ring.tx_pending = 512;
>  	ns->ethtool.ring.tx_max_pending = 4096;
>  }
>  
> diff --git a/tools/testing/selftests/net/lib/xdp_dummy.bpf.c b/tools/testing/selftests/net/lib/xdp_dummy.bpf.c
> new file mode 100644
> index 000000000000..d988b2e0cee8
> --- /dev/null
> +++ b/tools/testing/selftests/net/lib/xdp_dummy.bpf.c
> @@ -0,0 +1,13 @@
> +// SPDX-License-Identifier: GPL-2.0
> +
> +#define KBUILD_MODNAME "xdp_dummy"
> +#include <linux/bpf.h>
> +#include <bpf/bpf_helpers.h>
> +
> +SEC("xdp")
> +int xdp_dummy_prog(struct xdp_md *ctx)
> +{
> +	return XDP_PASS;
> +}
> +
> +char _license[] SEC("license") = "GPL";
> diff --git a/tools/testing/selftests/drivers/net/hds.py b/tools/testing/selftests/drivers/net/hds.py
> index 394971b25c0b..90807b21a6eb 100755
> --- a/tools/testing/selftests/drivers/net/hds.py
> +++ b/tools/testing/selftests/drivers/net/hds.py
> @@ -2,17 +2,54 @@
>  # SPDX-License-Identifier: GPL-2.0
>  
>  import errno
> +import os
>  from lib.py import ksft_run, ksft_exit, ksft_eq, ksft_raises, KsftSkipEx
> -from lib.py import EthtoolFamily, NlError
> +from lib.py import CmdExitFailure, EthtoolFamily, NlError
>  from lib.py import NetDrvEnv
> +from lib.py import defer, ethtool, ip
>  
> -def get_hds(cfg, netnl) -> None:
> +
> +def _get_hds_mode(cfg, netnl) -> str:
>      try:
>          rings = netnl.rings_get({'header': {'dev-index': cfg.ifindex}})
>      except NlError as e:
>          raise KsftSkipEx('ring-get not supported by device')
>      if 'tcp-data-split' not in rings:
>          raise KsftSkipEx('tcp-data-split not supported by device')
> +    return rings['tcp-data-split']
> +
> +
> +def _xdp_onoff(cfg):
> +    test_dir = os.path.dirname(os.path.realpath(__file__))
> +    prog = test_dir + "/../../net/lib/xdp_dummy.bpf.o"
> +    ip(f"link set dev %s xdp obj %s sec xdp" %
> +        (cfg.ifname, prog))
> +    ip(f"link set dev %s xdp off" % cfg.ifname)

nit: any reason you're not using {format} strings here?

    ip(f"link set dev {cfg.ifname} xdp obj {prog} sec xdp")
    ip(f"link set dev {cfg.ifname} xdp off")