openkylin
/
linux
mirror of https://gitee.com/openkylin/linux.git
9
0
Fork 0
Code Issues Projects Releases Wiki Activity

libbpf: Simplify BTF initialization logic 

Current implementation of bpf_object's BTF initialization is very convoluted
and thus prone to errors. It doesn't have to be like that. This patch
simplifies it significantly.

This code also triggered static analysis issues over logically dead code due
to redundant error checks. This simplification should fix that as well.

Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200117060801.1311525-3-andriin@fb.com
This commit is contained in:
Andrii Nakryiko 2020-01-16 22:07:59 -08:00 committed by Alexei Starovoitov
parent bc0eb9a333
commit b7d7f3e185
1 changed files with 6 additions and 13 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

19
tools/lib/bpf/libbpf.c
View File

@ -2297,16 +2297,18 @@ static int bpf_object__init_btf(struct bpf_object *obj,
Elf_Data *btf_data,
Elf_Data *btf_ext_data)
{
bool btf_required = bpf_object__is_btf_mandatory(obj);
int err = 0;
int err = -ENOENT;
if (btf_data) {
obj->btf = btf__new(btf_data->d_buf, btf_data->d_size);
if (IS_ERR(obj->btf)) {
err = PTR_ERR(obj->btf);
obj->btf = NULL;
pr_warn("Error loading ELF section %s: %d.\n",
BTF_ELF_SEC, err);
goto out;
}
err = 0;
}
if (btf_ext_data) {
if (!obj->btf) {
@ -2324,18 +2326,9 @@ static int bpf_object__init_btf(struct bpf_object *obj,
}
}
out:
if (err || IS_ERR(obj->btf)) {
if (btf_required)
err = err ? : PTR_ERR(obj->btf);
else
err = 0;
if (!IS_ERR_OR_NULL(obj->btf))
btf__free(obj->btf);
obj->btf = NULL;
}
if (btf_required && !obj->btf) {
if (err && bpf_object__is_btf_mandatory(obj)) {
pr_warn("BTF is required, but is missing or corrupted.\n");
return err == 0 ? -ENOENT : err;
return err;
}
return 0;
}