bpftool: Use a local bpf_perf_event_value to fix accessing its fields
Fix the following error when building bpftool: CLANG profiler.bpf.o CLANG pid_iter.bpf.o skeleton/profiler.bpf.c:18:21: error: invalid application of 'sizeof' to an incomplete type 'struct bpf_perf_event_value' __uint(value_size, sizeof(struct bpf_perf_event_value)); ^ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ tools/bpf/bpftool/bootstrap/libbpf/include/bpf/bpf_helpers.h:13:39: note: expanded from macro '__uint' tools/bpf/bpftool/bootstrap/libbpf/include/bpf/bpf_helper_defs.h:7:8: note: forward declaration of 'struct bpf_perf_event_value' struct bpf_perf_event_value; ^ struct bpf_perf_event_value is being used in the kernel only when CONFIG_BPF_EVENTS is enabled, so it misses a BTF entry then. Define struct bpf_perf_event_value___local with the `preserve_access_index` attribute inside the pid_iter BPF prog to allow compiling on any configs. It is a full mirror of a UAPI structure, so is compatible both with and w/o CO-RE. bpf_perf_event_read_value() requires a pointer of the original type, so a cast is needed. Fixes: 47c09d6a ("bpftool: Introduce "prog profile" command") Suggested-by:Andrii Nakryiko <andrii@kernel.org> Signed-off-by:
Alexander Lobakin <alobakin@pm.me> Signed-off-by:
Quentin Monnet <quentin@isovalent.com> Signed-off-by:
Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20230707095425.168126-5-quentin@isovalent.com
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