Allow specifying "target-less" SEC() definitions for tracing BPF programs,
both non-BTF-backed (kprobes, tracepoints, raw tracepoints) and BTF-backed
(fentry/fexit, iter, lsm, etc).
There are various situations where attach target cannot be known at
compilation time, so libbpf's insistence on specifying something leads to
users having to add random test like SEC("kprobe/whatever") and then
specifying correct target at runtime using APIs like
bpf_program__attach_kprobe().
So this patch set improves ergonomics by allowing simple SEC() definitions
that define BPF program type and nothing else. Such programs won't be
auto-attachable, of course, but they also won't fail skeleton auto-attachment,
just like we do this for uprobes.
Andrii Nakryiko (3):
libbpf: allow "incomplete" basic tracing SEC() definitions
libbpf: support target-less SEC() definitions for BTF-backed programs
selftests/bpf: use target-less SEC() definitions in various tests
tools/lib/bpf/libbpf.c | 118 ++++++++++++------
.../selftests/bpf/prog_tests/attach_probe.c | 10 ++
.../bpf/prog_tests/kprobe_multi_test.c | 14 +--
.../selftests/bpf/progs/kprobe_multi.c | 14 +++
.../selftests/bpf/progs/test_attach_probe.c | 23 +++-
.../selftests/bpf/progs/test_module_attach.c | 2 +-
6 files changed, 135 insertions(+), 46 deletions(-)
--
2.30.2
