[PATCH bpf-next v4 0/3] Annotate kfuncs in .BTF_ids section

[Daniel Xu]

=== Description ===

This is a bpf-treewide change that annotates all kfuncs as such inside
BTF_ids. This annotation eventually allows us to automatically generate
kfunc prototypes from bpftool.

We store this metadata inside a yet-unused flags field inside struct
btf_id_set8 (thanks Kumar!). pahole will be taught where to look.

More details about the full chain of events are available in commit 3's
description.

The accompanying pahole and bpftool changes can be viewed
here on these "frozen" branches [0][1].

[0]: https://github.com/danobi/pahole/tree/kfunc_btf-v3-mailed
[1]: https://github.com/danobi/linux/tree/kfunc_bpftool-mailed

=== Changelog ===

Changes from v3:
* Rebase to bpf-next and add missing annotation on new kfunc

Changes from v2:
* Only WARN() for vmlinux kfuncs

Changes from v1:
* Move WARN_ON() up a call level
* Also return error when kfunc set is not properly tagged
* Use BTF_KFUNCS_START/END instead of flags
* Rename BTF_SET8_KFUNC to BTF_SET8_KFUNCS

Daniel Xu (3):
  bpf: btf: Support flags for BTF_SET8 sets
  bpf: btf: Add BTF_KFUNCS_START/END macro pair
  bpf: treewide: Annotate BPF kfuncs in BTF

 Documentation/bpf/kfuncs.rst                  |  8 +++----
 drivers/hid/bpf/hid_bpf_dispatch.c            |  8 +++----
 fs/verity/measure.c                           |  4 ++--
 include/linux/btf_ids.h                       | 21 +++++++++++++++----
 kernel/bpf/btf.c                              |  8 +++++++
 kernel/bpf/cpumask.c                          |  4 ++--
 kernel/bpf/helpers.c                          |  8 +++----
 kernel/bpf/map_iter.c                         |  4 ++--
 kernel/cgroup/rstat.c                         |  4 ++--
 kernel/trace/bpf_trace.c                      |  8 +++----
 net/bpf/test_run.c                            |  8 +++----
 net/core/filter.c                             | 20 +++++++++---------
 net/core/xdp.c                                |  4 ++--
 net/ipv4/bpf_tcp_ca.c                         |  4 ++--
 net/ipv4/fou_bpf.c                            |  4 ++--
 net/ipv4/tcp_bbr.c                            |  4 ++--
 net/ipv4/tcp_cubic.c                          |  4 ++--
 net/ipv4/tcp_dctcp.c                          |  4 ++--
 net/netfilter/nf_conntrack_bpf.c              |  4 ++--
 net/netfilter/nf_nat_bpf.c                    |  4 ++--
 net/xfrm/xfrm_interface_bpf.c                 |  4 ++--
 net/xfrm/xfrm_state_bpf.c                     |  4 ++--
 .../selftests/bpf/bpf_testmod/bpf_testmod.c   |  8 +++----
 23 files changed, 87 insertions(+), 66 deletions(-)

-- 
2.42.1