Sorry for the delay on this. Discussed in [1]. It's a helper for proving to the verifier that your access in the array is valid. Happy to change names or whatever. =) Also added a libbpf helper function for mmapping an mmappable map. We've been using both in our ghost-BPF schedulers[2]. [1] https://lore.kernel.org/bpf/b4cb3423-b18d-8fad-7355-d8aa66ccfe4c@xxxxxxxxxx/T/ [2] https://github.com/google/ghost-userspace/blob/main/third_party/bpf/common.bpf.h#L218 v1: https://lore.kernel.org/bpf/20240103153307.553838-1-brho@xxxxxxxxxx/ - use libbpf's internal bpf_map_mmap_sz() - remove debugging cruft Barret Rhoden (2): libbpf: add helpers for mmapping maps selftests/bpf: add inline assembly helpers to access array elements tools/bpf/bpftool/gen.c | 16 +- tools/lib/bpf/libbpf.c | 18 ++ tools/lib/bpf/libbpf.h | 6 + tools/lib/bpf/libbpf.map | 4 + .../bpf/prog_tests/test_array_elem.c | 112 ++++++++++ .../selftests/bpf/progs/array_elem_test.c | 195 ++++++++++++++++++ tools/testing/selftests/bpf/progs/bpf_misc.h | 43 ++++ 7 files changed, 381 insertions(+), 13 deletions(-) create mode 100644 tools/testing/selftests/bpf/prog_tests/test_array_elem.c create mode 100644 tools/testing/selftests/bpf/progs/array_elem_test.c -- 2.43.0.472.g3155946c3a-goog
