Alexander Lobakin 67a43462ee bpftool: Define a local bpf_perf_link to fix accessing its fields ... When building bpftool with !CONFIG_PERF_EVENTS: skeleton/pid_iter.bpf.c:47:14: error: incomplete definition of type 'struct bpf_perf_link' perf_link = container_of(link, struct bpf_perf_link, link); ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ tools/bpf/bpftool/bootstrap/libbpf/include/bpf/bpf_helpers.h:74:22: note: expanded from macro 'container_of' ((type *)(__mptr - offsetof(type, member))); \ ^~~~~~~~~~~~~~~~~~~~~~ tools/bpf/bpftool/bootstrap/libbpf/include/bpf/bpf_helpers.h:68:60: note: expanded from macro 'offsetof' #define offsetof(TYPE, MEMBER) ((unsigned long)&((TYPE *)0)->MEMBER) ~~~~~~~~~~~^ skeleton/pid_iter.bpf.c:44:9: note: forward declaration of 'struct bpf_perf_link' struct bpf_perf_link *perf_link; ^ &bpf_perf_link is being defined and used only under the ifdef. Define struct bpf_perf_link___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 bpf_perf_link accesses later on. container_of() uses offsetof(), which does the necessary CO-RE relocation if the field is specified with `preserve_access_index` - as is the case for struct bpf_perf_link___local. Fixes: cbdaf71f7e ("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/20230707095425.168126-3-quentin@isovalent.com		2023-07-10 15:29:20 -07:00
..
pid_iter.bpf.c	bpftool: Define a local bpf_perf_link to fix accessing its fields	2023-07-10 15:29:20 -07:00
pid_iter.h	bpftool: Add bpf_cookie to link output	2022-03-15 15:07:27 -07:00
profiler.bpf.c	tools, bpftool: Remove two unused variables.	2020-10-29 15:23:18 +01:00