bpftool: use a local copy of perf_event to fix accessing :: Bpf_cookie
When CONFIG_PERF_EVENTS is not set, struct perf_event remains empty. However, the structure is being used by bpftool indirectly via BTF. This leads to: skeleton/pid_iter.bpf.c:49:30: error: no member named 'bpf_cookie' in 'struct perf_event' return BPF_CORE_READ(event, bpf_cookie); ~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~ ... skeleton/pid_iter.bpf.c:49:9: error: returning 'void' from a function with incompatible result type '__u64' (aka 'unsigned long long') return BPF_CORE_READ(event, bpf_cookie); ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Tools and samples can't use any CONFIG_ definitions, so the fields used there should always be present. Define struct perf_event___local with the `preserve_access_index` attribute inside the pid_iter BPF prog to allow compiling on any configs. CO-RE will substitute it with the real struct perf_event accesses later on. Fixes: cbdaf71f ("bpftool: Add bpf_cookie to link output") 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/20230707095425.168126-2-quentin@isovalent.com
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c628747c
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