[PATCH bpf-next v2 0/3] Annotate kfuncs in .BTF_ids section

Daniel Xu
2024-01-05T02:46:02Z

=== 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 changes (still needs some cleanup) can be viewed
here on this "frozen" branch [0].

[0]: https://github.com/danobi/pahole/tree/kfunc_btf-mailed

=== Changelog ===

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

drivers/hid/bpf/hid_bpf_dispatch.c | 8 +++----
fs/verity/measure.c | 4 ++--
include/linux/btf_ids.h | 21 +++++++++++++++----
kernel/bpf/btf.c | 4 ++++
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 | 16 +++++++-------
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 +++----
22 files changed, 77 insertions(+), 60 deletions(-)

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2.42.1