[PATCH net-next 2/5] libbpf: prefer global symbols as bpf program name source

[Roman Gushchin <guro@fb.com>]

Libbpf picks the name of the first symbol in the corresponding
elf section to use as a program name. But without taking symbol's
scope into account it may end's up with some local label
as a program name. E.g.:

$ bpftool cglist /sys/fs/cgroup/system.slice/tmp.mount/
      16 device          LBB0_10

Fix this by preferring global symbols as program name.
For instance:

$ bpftool cglist /sys/fs/cgroup/system.slice/tmp.mount/
      17 device          bpf_prog1

Signed-off-by: Roman Gushchin <guro@fb.com>
Cc: Martin KaFai Lau <kafai@fb.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Jakub Kicinski <jakub.kicinski@netronome.com>
---
 tools/lib/bpf/libbpf.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c
index 9f2410beaa18..5191afd46556 100644
--- a/tools/lib/bpf/libbpf.c
+++ b/tools/lib/bpf/libbpf.c
@@ -387,6 +387,8 @@ bpf_object__init_prog_names(struct bpf_object *obj)
 				continue;
 			if (sym.st_shndx != prog->idx)
 				continue;
+			if (GELF_ST_BIND(sym.st_info) != STB_GLOBAL)
+				continue;
 
 			name = elf_strptr(obj->efile.elf,
 					  obj->efile.strtabidx,
-- 
2.14.3