On 5/9/22 4:31 PM, Andrii Nakryiko wrote:
On Sun, May 1, 2022 at 12:00 PM Yonghong Song <yhs@xxxxxx> wrote:
Add BTF_KIND_ENUM64 support.
For example, the following enum is defined in uapi bpf.h.
$ cat core.c
enum A {
BPF_F_INDEX_MASK = 0xffffffffULL,
BPF_F_CURRENT_CPU = BPF_F_INDEX_MASK,
BPF_F_CTXLEN_MASK = (0xfffffULL << 32),
} g;
Compiled with
clang -target bpf -O2 -g -c core.c
Using bpftool to dump types and generate format C file:
$ bpftool btf dump file core.o
...
[1] ENUM64 'A' size=8 vlen=3
'BPF_F_INDEX_MASK' val=4294967295ULL
'BPF_F_CURRENT_CPU' val=4294967295ULL
'BPF_F_CTXLEN_MASK' val=4503595332403200ULL
$ bpftool btf dump file core.o format c
...
enum A {
BPF_F_INDEX_MASK = 4294967295ULL,
BPF_F_CURRENT_CPU = 4294967295ULL,
BPF_F_CTXLEN_MASK = 4503595332403200ULL,
maybe we should have some heuristic that if the value is "big enough"
(e.g., larger than 1-128 millions) and is unsigned we should emit it
as hex?
I thought about this. But since you are also suggesting this, I will
do this (greater than 1 million).
};
...
The 64bit value is represented properly in BTF and C dump.
Signed-off-by: Yonghong Song <yhs@xxxxxx>
---
just minor nits, LGTM
Acked-by: Andrii Nakryiko <andrii@xxxxxxxxxx>
tools/bpf/bpftool/btf.c | 47 ++++++++++++++++++++++++++++++++--
tools/bpf/bpftool/btf_dumper.c | 32 +++++++++++++++++++++++
tools/bpf/bpftool/gen.c | 1 +
3 files changed, 78 insertions(+), 2 deletions(-)
[...]
+ case BTF_KIND_ENUM64: {
+ const struct btf_enum64 *v = (const void *)(t + 1);
can use btf_enum64() helper from libbpf?
+ __u16 vlen = BTF_INFO_VLEN(t->info);
btf_vlen(t)
I copied the code from above BTF_KIND_ENUM. But I certainly can do this.
+ int i;
+
+ if (json_output) {
+ jsonw_uint_field(w, "size", t->size);
+ jsonw_uint_field(w, "vlen", vlen);
+ jsonw_name(w, "values");
+ jsonw_start_array(w);
+ } else {
+ printf(" size=%u vlen=%u", t->size, vlen);
+ }
+ for (i = 0; i < vlen; i++, v++) {
+ const char *name = btf_str(btf, v->name_off);
+ __u64 val = (__u64)v->hi32 << 32 | v->lo32;
() ?
okay.
+
+ if (json_output) {
+ jsonw_start_object(w);
+ jsonw_string_field(w, "name", name);
+ if (btf_kflag(t))
+ jsonw_uint_field(w, "val", val);
+ else
+ jsonw_int_field(w, "val", val);
+ jsonw_end_object(w);
+ } else {
+ if (btf_kflag(t))
+ printf("\n\t'%s' val=%lluULL", name, val);
+ else
+ printf("\n\t'%s' val=%lldLL", name, val);
}
}
if (json_output)
diff --git a/tools/bpf/bpftool/btf_dumper.c b/tools/bpf/bpftool/btf_dumper.c
index f5dddf8ef404..f9f38384b9a6 100644
--- a/tools/bpf/bpftool/btf_dumper.c
+++ b/tools/bpf/bpftool/btf_dumper.c
@@ -182,6 +182,35 @@ static int btf_dumper_enum(const struct btf_dumper *d,
return 0;
}
+static int btf_dumper_enum64(const struct btf_dumper *d,
+ const struct btf_type *t,
+ const void *data)
+{
+ const struct btf_enum64 *enums = btf_enum64(t);
+ __u32 hi32, lo32;
+ __u64 value;
+ __u16 i;
+
+ if (t->size != 8)
+ return -EINVAL;
no need
sure.
+
+ value = *(__u64 *)data;
+ hi32 = value >> 32;
+ lo32 = (__u32)value;
+
[...]
