diff options
| author | Eduard Zingerman <eddyz87@gmail.com> | 2024-03-06 12:45:17 +0200 |
|---|---|---|
| committer | Andrii Nakryiko <andrii@kernel.org> | 2024-03-06 15:18:15 -0800 |
| commit | 8db052615a9780b45e26d6afabc7abefe1ba20ac (patch) | |
| tree | 0be700562e5dd26252c1f41e1d3dbc45445dec06 /tools | |
| parent | d9ab2f76ef5abb76190ffb42d83bdc6caede807e (diff) | |
libbpf: Honor autocreate flag for struct_ops maps
Skip load steps for struct_ops maps not marked for automatic creation.
This should allow to load bpf object in situations like below:
SEC("struct_ops/foo") int BPF_PROG(foo) { ... }
SEC("struct_ops/bar") int BPF_PROG(bar) { ... }
struct test_ops___v1 {
int (*foo)(void);
};
struct test_ops___v2 {
int (*foo)(void);
int (*does_not_exist)(void);
};
SEC(".struct_ops.link")
struct test_ops___v1 map_for_old = {
.test_1 = (void *)foo
};
SEC(".struct_ops.link")
struct test_ops___v2 map_for_new = {
.test_1 = (void *)foo,
.does_not_exist = (void *)bar
};
Suppose program is loaded on old kernel that does not have definition
for 'does_not_exist' struct_ops member. After this commit it would be
possible to load such object file after the following tweaks:
bpf_program__set_autoload(skel->progs.bar, false);
bpf_map__set_autocreate(skel->maps.map_for_new, false);
Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: David Vernet <void@manifault.com>
Link: https://lore.kernel.org/bpf/20240306104529.6453-4-eddyz87@gmail.com
Diffstat (limited to 'tools')
| -rw-r--r-- | tools/lib/bpf/libbpf.c | 18 |
1 files changed, 15 insertions, 3 deletions
diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c index 2c0cb72bc7a4..1fb9a4f237b4 100644 --- a/tools/lib/bpf/libbpf.c +++ b/tools/lib/bpf/libbpf.c @@ -1212,6 +1212,9 @@ static int bpf_object__init_kern_struct_ops_maps(struct bpf_object *obj) if (!bpf_map__is_struct_ops(map)) continue; + if (!map->autocreate) + continue; + err = bpf_map__init_kern_struct_ops(map); if (err) return err; @@ -8133,11 +8136,20 @@ static void bpf_map_prepare_vdata(const struct bpf_map *map) static int bpf_object_prepare_struct_ops(struct bpf_object *obj) { + struct bpf_map *map; int i; - for (i = 0; i < obj->nr_maps; i++) - if (bpf_map__is_struct_ops(&obj->maps[i])) - bpf_map_prepare_vdata(&obj->maps[i]); + for (i = 0; i < obj->nr_maps; i++) { + map = &obj->maps[i]; + + if (!bpf_map__is_struct_ops(map)) + continue; + + if (!map->autocreate) + continue; + + bpf_map_prepare_vdata(map); + } return 0; } |