[bpf-next,v6,0/5] Add bpf_xdp_get_xfrm_state() kfunc

Message

Daniel Xu Dec. 14, 2023, 10:49 p.m. UTC

This patchset adds two kfunc helpers, bpf_xdp_get_xfrm_state() and
bpf_xdp_xfrm_state_release() that wrap xfrm_state_lookup() and
xfrm_state_put(). The intent is to support software RSS (via XDP) for
the ongoing/upcoming ipsec pcpu work [0]. Recent experiments performed
on (hopefully) reproducible AWS testbeds indicate that single tunnel
pcpu ipsec can reach line rate on 100G ENA nics.

Note this patchset only tests/shows generic xfrm_state access. The
"secret sauce" (if you can really even call it that) involves accessing
a soon-to-be-upstreamed pcpu_num field in xfrm_state. Early example is
available here [1].

[0]: https://datatracker.ietf.org/doc/draft-ietf-ipsecme-multi-sa-performance/03/
[1]: https://github.com/danobi/xdp-tools/blob/e89a1c617aba3b50d990f779357d6ce2863ecb27/xdp-bench/xdp_redirect_cpumap.bpf.c#L385-L406

Changes from v5:
* Improve kfunc doc comments
* Remove extraneous replay-window setting on selftest reverse path
* Squash two kfunc commits into one
* Rebase to bpf-next to pick up bitfield write patches
* Remove testing of opts.error in selftest prog

Changes from v4:
* Fixup commit message for selftest
* Set opts->error -ENOENT for !x
* Revert single file xfrm + bpf

Changes from v3:
* Place all xfrm bpf integrations in xfrm_bpf.c
* Avoid using nval as a temporary
* Rebase to bpf-next
* Remove extraneous __failure_unpriv annotation for verifier tests

Changes from v2:
* Fix/simplify BPF_CORE_WRITE_BITFIELD() algorithm
* Added verifier tests for bitfield writes
* Fix state leakage across test_tunnel subtests

Changes from v1:
* Move xfrm tunnel tests to test_progs
* Fix writing to opts->error when opts is invalid
* Use __bpf_kfunc_start_defs()
* Remove unused vxlanhdr definition
* Add and use BPF_CORE_WRITE_BITFIELD() macro
* Make series bisect clean

Changes from RFCv2:
* Rebased to ipsec-next
* Fix netns leak

Changes from RFCv1:
* Add Antony's commit tags
* Add KF_ACQUIRE and KF_RELEASE semantics

Daniel Xu (5):
  bpf: xfrm: Add bpf_xdp_get_xfrm_state() kfunc
  bpf: selftests: test_tunnel: Setup fresh topology for each subtest
  bpf: selftests: test_tunnel: Use vmlinux.h declarations
  bpf: selftests: Move xfrm tunnel test to test_progs
  bpf: xfrm: Add selftest for bpf_xdp_get_xfrm_state()

 include/net/xfrm.h                            |   9 +
 net/xfrm/Makefile                             |   1 +
 net/xfrm/xfrm_policy.c                        |   2 +
 net/xfrm/xfrm_state_bpf.c                     | 134 +++++++++++++++
 .../selftests/bpf/prog_tests/test_tunnel.c    | 162 +++++++++++++++++-
 .../selftests/bpf/progs/bpf_tracing_net.h     |   1 +
 .../selftests/bpf/progs/test_tunnel_kern.c    | 138 ++++++++-------
 tools/testing/selftests/bpf/test_tunnel.sh    |  92 ----------
 8 files changed, 384 insertions(+), 155 deletions(-)
 create mode 100644 net/xfrm/xfrm_state_bpf.c

Comments

[e-mail] Dec. 15, 2023, 1:30 a.m. UTC | #1

Hello:

This series was applied to bpf/bpf-next.git (master)
by Alexei Starovoitov <[e-mail]>:

On Thu, 14 Dec 2023 15:49:01 -0700 you wrote:
> This patchset adds two kfunc helpers, bpf_xdp_get_xfrm_state() and
> bpf_xdp_xfrm_state_release() that wrap xfrm_state_lookup() and
> xfrm_state_put(). The intent is to support software RSS (via XDP) for
> the ongoing/upcoming ipsec pcpu work [0]. Recent experiments performed
> on (hopefully) reproducible AWS testbeds indicate that single tunnel
> pcpu ipsec can reach line rate on 100G ENA nics.
> 
> [...]

Here is the summary with links:
  - [bpf-next,v6,1/5] bpf: xfrm: Add bpf_xdp_get_xfrm_state() kfunc
    https://git.kernel.org/bpf/bpf-next/c/8f0ec8c68175
  - [bpf-next,v6,2/5] bpf: selftests: test_tunnel: Setup fresh topology for each subtest
    https://git.kernel.org/bpf/bpf-next/c/77a7a8220f0d
  - [bpf-next,v6,3/5] bpf: selftests: test_tunnel: Use vmlinux.h declarations
    https://git.kernel.org/bpf/bpf-next/c/02b4e126e6a5
  - [bpf-next,v6,4/5] bpf: selftests: Move xfrm tunnel test to test_progs
    https://git.kernel.org/bpf/bpf-next/c/e7adc8291a9e
  - [bpf-next,v6,5/5] bpf: xfrm: Add selftest for bpf_xdp_get_xfrm_state()
    https://git.kernel.org/bpf/bpf-next/c/2cd07b0eb08c

You are awesome, thank you!