On 5/31/22 5:07 PM, Andrii Nakryiko wrote:
On Thu, May 26, 2022 at 11:55 AM Yonghong Song <yhs@xxxxxx> wrote:
The enum64 relocation support is added. The bpf local type
could be either enum or enum64 and the remote type could be
either enum or enum64 too. The all combinations of local enum/enum64
and remote enum/enum64 are supported.
Signed-off-by: Yonghong Song <yhs@xxxxxx>
---
tools/lib/bpf/btf.h | 7 +++++
tools/lib/bpf/libbpf.c | 7 ++---
tools/lib/bpf/relo_core.c | 54 +++++++++++++++++++++++++++------------
3 files changed, 48 insertions(+), 20 deletions(-)
[...]
local_essent_len = bpf_core_essential_name_len(local_acc->name);
- for (i = 0, e = btf_enum(targ_type); i < btf_vlen(targ_type); i++, e++) {
- targ_name = btf__name_by_offset(targ_spec->btf, e->name_off);
+ for (i = 0; i < btf_vlen(targ_type); i++) {
+ if (btf_is_enum(targ_type))
+ name_off = btf_enum(targ_type)[i].name_off;
+ else
+ name_off = btf_enum64(targ_type)[i].name_off;
+
+ targ_name = btf__name_by_offset(targ_spec->btf, name_off);
targ_essent_len = bpf_core_essential_name_len(targ_name);
if (targ_essent_len != local_essent_len)
continue;
@@ -680,8 +688,7 @@ static int bpf_core_calc_field_relo(const char *prog_name,
*val = byte_sz;
break;
case BPF_CORE_FIELD_SIGNED:
- /* enums will be assumed unsigned */
- *val = btf_is_enum(mt) ||
+ *val = btf_type_is_any_enum(mt) ||
wouldn't this be more correct with kflag meaning "signed":
(btf_type_is_any_enum(mt) && btf_kflag(mt)) ||
Will fix.
?
(btf_int_encoding(mt) & BTF_INT_SIGNED);
if (validate)
*validate = true; /* signedness is never ambiguous */
@@ -754,7 +761,6 @@ static int bpf_core_calc_enumval_relo(const struct bpf_core_relo *relo,
__u64 *val)
{
const struct btf_type *t;
- const struct btf_enum *e;
switch (relo->kind) {
case BPF_CORE_ENUMVAL_EXISTS:
@@ -764,8 +770,10 @@ static int bpf_core_calc_enumval_relo(const struct bpf_core_relo *relo,
if (!spec)
return -EUCLEAN; /* request instruction poisoning */
t = btf_type_by_id(spec->btf, spec->spec[0].type_id);
- e = btf_enum(t) + spec->spec[0].idx;
- *val = e->val;
+ if (btf_is_enum(t))
+ *val = btf_enum(t)[spec->spec[0].idx].val;
+ else
+ *val = btf_enum64_value(btf_enum64(t) + spec->spec[0].idx);
break;
default:
return -EOPNOTSUPP;
@@ -1060,7 +1068,6 @@ int bpf_core_patch_insn(const char *prog_name, struct bpf_insn *insn,
int bpf_core_format_spec(char *buf, size_t buf_sz, const struct bpf_core_spec *spec)
{
const struct btf_type *t;
- const struct btf_enum *e;
const char *s;
__u32 type_id;
int i, len = 0;
@@ -1089,10 +1096,23 @@ int bpf_core_format_spec(char *buf, size_t buf_sz, const struct bpf_core_spec *s
if (core_relo_is_enumval_based(spec->relo_kind)) {
t = skip_mods_and_typedefs(spec->btf, type_id, NULL);
- e = btf_enum(t) + spec->raw_spec[0];
- s = btf__name_by_offset(spec->btf, e->name_off);
+ if (btf_is_enum(t)) {
+ const struct btf_enum *e;
+ const char *fmt_str;
+
+ e = btf_enum(t) + spec->raw_spec[0];
+ s = btf__name_by_offset(spec->btf, e->name_off);
+ fmt_str = BTF_INFO_KFLAG(t->info) ? "::%s = %d" : "::%s = %u";
minor nit: btf_kflag(t) instead of BTF_INFO_KFLAGS(t->info)?
relo_core.c is used by both the kernel and libbpf. The btf_kflag
is not available in kernel. That is why I am using BTF_INFO_KFLAG.
I guess I can introduce btf_kflag in the kernel to avoid using
BTF_INFO_KFLAG.
+ append_buf(fmt_str, s, e->val);
+ } else {
+ const struct btf_enum64 *e;
+ const char *fmt_str;
- append_buf("::%s = %u", s, e->val);
+ e = btf_enum64(t) + spec->raw_spec[0];
+ s = btf__name_by_offset(spec->btf, e->name_off);
+ fmt_str = BTF_INFO_KFLAG(t->info) ? "::%s = %lld" : "::%s = %llu";
+ append_buf(fmt_str, s, (unsigned long long)btf_enum64_value(e));
+ }
return len;
}
--
2.30.2
