[bpf-next,v1,0/3] Add skb + xdp dynptrs

Message

Joanne Koong July 26, 2022, 6:47 p.m. UTC

This patchset is the 2nd in the dynptr series. The 1st can be found here [0].

This patchset adds skb and xdp type dynptrs, which have two main benefits for
packet parsing:
    * allowing operations on sizes that are not statically known at
      compile-time (eg variable-sized accesses).
    * more ergonomic and less brittle iteration through data (eg does not need
      manual if checking for being within bounds of data_end)

When comparing the differences in runtime for packet parsing without dynptrs
vs. with dynptrs, there is no noticeable difference (see patch 3 for more
details).

[0] https://lore.kernel.org/bpf/[e-mail]/

Joanne Koong (3):
  bpf: Add skb dynptrs
  bpf: Add xdp dynptrs
  selftests/bpf: tests for using dynptrs to parse skb and xdp buffers

 include/linux/bpf.h                           |  14 ++-
 include/linux/filter.h                        |   7 ++
 include/uapi/linux/bpf.h                      |  58 ++++++++-
 kernel/bpf/helpers.c                          |  64 +++++++++-
 kernel/bpf/verifier.c                         |  48 +++++++-
 net/core/filter.c                             |  99 +++++++++++++--
 tools/include/uapi/linux/bpf.h                |  58 ++++++++-
 .../testing/selftests/bpf/prog_tests/dynptr.c |  85 ++++++++++---
 .../selftests/bpf/prog_tests/dynptr_xdp.c     |  49 ++++++++
 .../testing/selftests/bpf/progs/dynptr_fail.c |  76 ++++++++++++
 .../selftests/bpf/progs/dynptr_success.c      |  32 +++++
 .../selftests/bpf/progs/test_dynptr_xdp.c     | 115 ++++++++++++++++++
 .../selftests/bpf/progs/test_l4lb_noinline.c  |  71 +++++------
 tools/testing/selftests/bpf/progs/test_xdp.c  |  95 +++++++--------
 .../selftests/bpf/test_tcp_hdr_options.h      |   1 +
 15 files changed, 741 insertions(+), 131 deletions(-)
 create mode 100644 tools/testing/selftests/bpf/prog_tests/dynptr_xdp.c
 create mode 100644 tools/testing/selftests/bpf/progs/test_dynptr_xdp.c