[xdp-hints] [PATCH bpf-next v6 00/18] XDP metadata via kfuncs for ice + VLAN hint

[Larysa Zaremba <larysa.zaremba@intel.com>]

This series introduces XDP hints via kfuncs [0] to the ice driver.

Series brings the following existing hints to the ice driver:
 - HW timestamp
 - RX hash with type

Series also introduces VLAN tag with protocol XDP hint, it now be accessed by
XDP and userspace (AF_XDP) programs. They can also be checked with xdp_metadata
test and xdp_hw_metadata program.

On Maciej's request, I provide some numbers about impact of these patches
on ice performance.
ZC:
* Full hints implementation before addition of the static key decreases
  pps in ZC mode by 6%
* Adding a static key eliminates this drop. Overall performce difference
  compared to a clean tree in inconsequential.

skb (packets with invalid IP, dropped by stack):
* Overall, patchset improves peak performance in skb mode by about 0.5%

[0] https://patchwork.kernel.org/project/netdevbpf/cover/20230119221536.3349901-1-sdf@google.com/

Intermediate RFC v2:
https://lore.kernel.org/bpf/20230927075124.23941-1-larysa.zaremba@intel.com/
Intermediate RFC v1:
https://lore.kernel.org/bpf/20230824192703.712881-1-larysa.zaremba@intel.com/
v5:
https://lore.kernel.org/bpf/20230811161509.19722-1-larysa.zaremba@intel.com/
v4:
https://lore.kernel.org/bpf/20230728173923.1318596-1-larysa.zaremba@intel.com/
v3:
https://lore.kernel.org/bpf/20230719183734.21681-1-larysa.zaremba@intel.com/
v2:
https://lore.kernel.org/bpf/20230703181226.19380-1-larysa.zaremba@intel.com/
v1:
https://lore.kernel.org/all/20230512152607.992209-1-larysa.zaremba@intel.com/

Changes since v5:
* drop checksum hint from the patchset entirely
* Alex's patch that lifts the data_meta size limitation is no longer
  required in this patchset, so will be sent separately
* new patch: hide some ice hints code behind a static key
* fix several bugs in ZC mode (ice)
* change argument order in VLAN hint kfunc (tci, proto -> proto, tci)
* cosmetic changes
* analyze performance impact

Changes since v4:
* Drop the concept of partial checksum from the hint design
* Drop the concept of checksum level from the hint design

Changes since v3:
* use XDP_CHECKSUM_VALID_LVL0 + csum_level instead of csum_level + 1
* fix spelling mistakes
* read XDP timestamp unconditionally
* add TO_STR() macro

Changes since v2:
* redesign checksum hint, so now it gives full status
* rename vlan_tag -> vlan_tci, where applicable
* use open_netns() and close_netns() in xdp_metadata
* improve VLAN hint documentation
* replace CFI with DEI
* use VLAN_VID_MASK in xdp_metadata
* make vlan_get_tag() return -ENODATA
* remove unused rx_ptype in ice_xsk.c
* fix ice timestamp code division between patches

Changes since v1:
* directly return RX hash, RX timestamp and RX checksum status
  in skb-common functions
* use intermediate enum value for checksum status in ice
* get rid of ring structure dependency in ice kfunc implementation
* make variables const, when possible, in ice implementation
* use -ENODATA instead of -EOPNOTSUPP for driver implementation
* instead of having 2 separate functions for c-tag and s-tag,
  use 1 function that outputs both VLAN tag and protocol ID
* improve documentation for introduced hints
* update xdp_metadata selftest to test new hints
* implement new hints in veth, so they can be tested in xdp_metadata
* parse VLAN tag in xdp_hw_metadata

Larysa Zaremba (18):
  ice: make RX hash reading code more reusable
  ice: make RX HW timestamp reading code more reusable
  ice: Make ptype internal to descriptor info processing
  ice: Introduce ice_xdp_buff
  ice: Support HW timestamp hint
  ice: Support RX hash XDP hint
  ice: Support XDP hints in AF_XDP ZC mode
  xdp: Add VLAN tag hint
  ice: Implement VLAN tag hint
  ice: use VLAN proto from ring packet context in skb path
  ice: put XDP meta sources assignment under a static key condition
  veth: Implement VLAN tag XDP hint
  net: make vlan_get_tag() return -ENODATA instead of -EINVAL
  mlx5: implement VLAN tag XDP hint
  selftests/bpf: Allow VLAN packets in xdp_hw_metadata
  selftests/bpf: Add flags and VLAN hint to xdp_hw_metadata
  selftests/bpf: Use AF_INET for TX in xdp_metadata
  selftests/bpf: Check VLAN tag and proto in xdp_metadata

 Documentation/networking/xdp-rx-metadata.rst  |   8 +-
 drivers/net/ethernet/intel/ice/ice.h          |   3 +
 drivers/net/ethernet/intel/ice/ice_ethtool.c  |   2 +-
 .../net/ethernet/intel/ice/ice_lan_tx_rx.h    | 412 +++++++++---------
 drivers/net/ethernet/intel/ice/ice_lib.c      |   2 +-
 drivers/net/ethernet/intel/ice/ice_main.c     |  35 ++
 drivers/net/ethernet/intel/ice/ice_ptp.c      |  25 +-
 drivers/net/ethernet/intel/ice/ice_ptp.h      |  16 +-
 drivers/net/ethernet/intel/ice/ice_txrx.c     |  20 +-
 drivers/net/ethernet/intel/ice/ice_txrx.h     |  29 +-
 drivers/net/ethernet/intel/ice/ice_txrx_lib.c | 209 ++++++++-
 drivers/net/ethernet/intel/ice/ice_txrx_lib.h |  18 +-
 drivers/net/ethernet/intel/ice/ice_xsk.c      |  49 ++-
 .../net/ethernet/mellanox/mlx5/core/en/xdp.c  |  15 +
 drivers/net/veth.c                            |  19 +
 include/linux/if_vlan.h                       |   4 +-
 include/linux/mlx5/device.h                   |   2 +-
 include/net/xdp.h                             |   9 +
 include/uapi/linux/netdev.h                   |   5 +-
 net/core/xdp.c                                |  33 ++
 tools/include/uapi/linux/netdev.h             |   5 +-
 .../selftests/bpf/prog_tests/xdp_metadata.c   | 184 ++++----
 .../selftests/bpf/progs/xdp_hw_metadata.c     |  38 +-
 .../selftests/bpf/progs/xdp_metadata.c        |   5 +
 tools/testing/selftests/bpf/testing_helpers.h |   3 +
 tools/testing/selftests/bpf/xdp_hw_metadata.c |  38 +-
 tools/testing/selftests/bpf/xdp_metadata.h    |  34 +-
 27 files changed, 816 insertions(+), 406 deletions(-)

-- 
2.41.0