For very large ELF objects (with many sections), we could get special
value SHN_XINDEX (65535) for symbol's st_shndx.
This patch is adding code to detect the optional extended section index
table and use it to resolve symbol's section index.
Adding elf_symtab__for_each_symbol_index macro that returns symbol's
section index and usign it in collect functions.
Tested by running pahole on kernel compiled with:
make KCFLAGS="-ffunction-sections -fdata-sections" -j$(nproc) vmlinux
and ensure FUNC records are generated and match normal build (without
above KCFLAGS).
Also bpf selftest passed and generated kernel BTF, is same as without
the patch.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Hao Luo <haoluo@google.com>
Cc: Joe Lawrence <joe.lawrence@redhat.com>
Cc: John Fastabend <john.fastabend@gmail.com>
Cc: KP Singh <kpsingh@chromium.org>
Cc: Mark Wieelard <mjw@redhat.com>
Cc: Martin KaFai Lau <kafai@fb.com>
Cc: Song Liu <songliubraving@fb.com>
Cc: Yonghong Song <yhs@fb.com>
Cc: bpf@vger.kernel.org
Cc: dwarves@vger.kernel.org
Cc: netdev@vger.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
As Thomas Gleixner wisely pointed out, using 'self' is stupid, it
doesn't convey useful information, so use sensible names.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
And ditch the iterate calling a function interface. I'm trying to get rid of
that in the core (cu__for_each+callback+filter, etc) because doit it
explicitely, like in the kernel, where you have a foo__for_each_bar and do the
filtering directly and process the data, if the processing is simple, right in
the body of the loop, instead of having to go back and forth thru functions.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
We will need this when encoding the CTF functions section. Things like lookup
a function by its address when converting from a DW_TAG_subprogram to a CTF
function, for instance.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Arnaldo Carvalho de Melo
Jiri Olsa
Domenico Andreoli