[PATCH bpf-next v5 00/17] xdp: hints via kfuncs

[Stanislav Fomichev <sdf@google.com>]

Please see the first patch in the series for the overall
design and use-cases.

See the following email from Toke for the per-packet metadata overhead:
https://lore.kernel.org/bpf/20221206024554.3826186-1-sdf@google.com/T/#m49d48ea08d525ec88360c7d14c4d34fb0e45e798

Recent changes:

- Various updates to the documentation (Toke)

- !CONFIG_NET for bpf_dev_bound_resolve_kfunc (Martin)

- Comment about race when resolving multiple kfuncs vs attach (Martin)

- Move kfuncs check part under add_kfunc_call (Martin)

- Add missing freplace locks (via bpf_prog_dev_bound_inherit and
  bpf_prog_dev_bound_match) (Martin)

- Rework selftest to expect 0 HW timestamp instead of adding test-specific
  code to veth (Martin)

- Separate patches for offload.c refactoring (Martin)

- Remove sem unlock in __bpf_offload_dev_netdev_register (Martin)

- Rework error handling in bpf_prog_offload_init (Martin)

- Fix wrongly placed list_del_init and unroll
  bpf_dev_bound_try_remove_netdev (Martin)

- Drop locks from bpf_offload_init (Martin)

- Swap the order of bpf_dev_bound_netdev_unregister and
  dev_xdp_uninstall (Martin)

- Return HW timestamp in veth kfunc (Jesper)

- Various fixes around documentation (David)

- Don't define kfunc prototypes (David)

- More clear XDP_METADATA_KFUNC argument names (David)

Prior art (to record pros/cons for different approaches):

- Stable UAPI approach:
  https://lore.kernel.org/bpf/20220628194812.1453059-1-alexandr.lobakin@intel.com/
- Metadata+BTF_ID appoach:
  https://lore.kernel.org/bpf/166256538687.1434226.15760041133601409770.stgit@firesoul/
- v4:
  https://lore.kernel.org/bpf/20221213023605.737383-1-sdf@google.com/
- v3:
  https://lore.kernel.org/bpf/20221206024554.3826186-1-sdf@google.com/
- v2:
  https://lore.kernel.org/bpf/20221121182552.2152891-1-sdf@google.com/
- v1:
  https://lore.kernel.org/bpf/20221115030210.3159213-1-sdf@google.com/
- kfuncs v2 RFC:
  https://lore.kernel.org/bpf/20221027200019.4106375-1-sdf@google.com/
- kfuncs v1 RFC:
  https://lore.kernel.org/bpf/20221104032532.1615099-1-sdf@google.com/

Cc: John Fastabend <john.fastabend@gmail.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Martin KaFai Lau <martin.lau@linux.dev>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: Willem de Bruijn <willemb@google.com>
Cc: Jesper Dangaard Brouer <brouer@redhat.com>
Cc: Anatoly Burakov <anatoly.burakov@intel.com>
Cc: Alexander Lobakin <alexandr.lobakin@intel.com>
Cc: Magnus Karlsson <magnus.karlsson@gmail.com>
Cc: Maryam Tahhan <mtahhan@redhat.com>
Cc: xdp-hints@xdp-project.net
Cc: netdev@vger.kernel.org

Stanislav Fomichev (13):
  bpf: Document XDP RX metadata
  bpf: Rename bpf_{prog,map}_is_dev_bound to is_offloaded
  bpf: Move offload initialization into late_initcall
  bpf: Reshuffle some parts of bpf/offload.c
  bpf: Introduce device-bound XDP programs
  selftests/bpf: Update expected test_offload.py messages
  bpf: XDP metadata RX kfuncs
  veth: Introduce veth_xdp_buff wrapper for xdp_buff
  veth: Support RX XDP metadata
  selftests/bpf: Verify xdp_metadata xdp->af_xdp path
  net/mlx4_en: Introduce wrapper for xdp_buff
  net/mlx4_en: Support RX XDP metadata
  selftests/bpf: Simple program to dump XDP RX metadata

Toke Høiland-Jørgensen (4):
  bpf: Support consuming XDP HW metadata from fext programs
  xsk: Add cb area to struct xdp_buff_xsk
  net/mlx5e: Introduce wrapper for xdp_buff
  net/mlx5e: Support RX XDP metadata

 Documentation/networking/index.rst            |   1 +
 Documentation/networking/xdp-rx-metadata.rst  | 107 +++++
 drivers/net/ethernet/mellanox/mlx4/en_clock.c |  13 +-
 .../net/ethernet/mellanox/mlx4/en_netdev.c    |   6 +
 drivers/net/ethernet/mellanox/mlx4/en_rx.c    |  63 ++-
 drivers/net/ethernet/mellanox/mlx4/mlx4_en.h  |   5 +
 drivers/net/ethernet/mellanox/mlx5/core/en.h  |  11 +-
 .../net/ethernet/mellanox/mlx5/core/en/xdp.c  |  26 +-
 .../net/ethernet/mellanox/mlx5/core/en/xdp.h  |  11 +-
 .../ethernet/mellanox/mlx5/core/en/xsk/rx.c   |  35 +-
 .../ethernet/mellanox/mlx5/core/en/xsk/rx.h   |   2 +
 .../net/ethernet/mellanox/mlx5/core/en_main.c |   6 +
 .../net/ethernet/mellanox/mlx5/core/en_rx.c   |  99 +++--
 drivers/net/netdevsim/bpf.c                   |   4 -
 drivers/net/veth.c                            |  87 ++--
 include/linux/bpf.h                           |  53 ++-
 include/linux/netdevice.h                     |   7 +
 include/net/xdp.h                             |  21 +
 include/net/xsk_buff_pool.h                   |   5 +
 include/uapi/linux/bpf.h                      |   5 +
 kernel/bpf/core.c                             |  12 +-
 kernel/bpf/offload.c                          | 404 +++++++++++------
 kernel/bpf/syscall.c                          |  39 +-
 kernel/bpf/verifier.c                         |  54 ++-
 net/bpf/test_run.c                            |   3 +
 net/core/dev.c                                |   9 +-
 net/core/filter.c                             |   2 +-
 net/core/xdp.c                                |  50 +++
 tools/include/uapi/linux/bpf.h                |   5 +
 tools/testing/selftests/bpf/.gitignore        |   1 +
 tools/testing/selftests/bpf/Makefile          |   8 +-
 .../selftests/bpf/prog_tests/xdp_metadata.c   | 412 ++++++++++++++++++
 .../selftests/bpf/progs/xdp_hw_metadata.c     |  81 ++++
 .../selftests/bpf/progs/xdp_metadata.c        |  64 +++
 .../selftests/bpf/progs/xdp_metadata2.c       |  23 +
 tools/testing/selftests/bpf/test_offload.py   |  10 +-
 tools/testing/selftests/bpf/xdp_hw_metadata.c | 405 +++++++++++++++++
 tools/testing/selftests/bpf/xdp_metadata.h    |  15 +
 38 files changed, 1883 insertions(+), 281 deletions(-)
 create mode 100644 Documentation/networking/xdp-rx-metadata.rst
 create mode 100644 tools/testing/selftests/bpf/prog_tests/xdp_metadata.c
 create mode 100644 tools/testing/selftests/bpf/progs/xdp_hw_metadata.c
 create mode 100644 tools/testing/selftests/bpf/progs/xdp_metadata.c
 create mode 100644 tools/testing/selftests/bpf/progs/xdp_metadata2.c
 create mode 100644 tools/testing/selftests/bpf/xdp_hw_metadata.c
 create mode 100644 tools/testing/selftests/bpf/xdp_metadata.h

-- 
2.39.0.314.g84b9a713c41-goog