From 58a53978fdf65d12dae1798e44120efb992a3615 Mon Sep 17 00:00:00 2001 From: Yonghong Song Date: Mon, 6 Jun 2022 23:26:52 -0700 Subject: [PATCH] bpftool: Add btf enum64 support 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' encoding=UNSIGNED 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, }; ... Note that for raw btf output, the encoding (UNSIGNED or SIGNED) is printed out as well. The 64bit value is also represented properly in BTF and C dump. Acked-by: Andrii Nakryiko Signed-off-by: Yonghong Song Link: https://lore.kernel.org/r/20220607062652.3722649-1-yhs@fb.com Signed-off-by: Alexei Starovoitov --- tools/bpf/bpftool/btf.c | 57 ++++++++++++++++++++++++++++++++-- tools/bpf/bpftool/btf_dumper.c | 29 +++++++++++++++++ tools/bpf/bpftool/gen.c | 1 + 3 files changed, 84 insertions(+), 3 deletions(-) diff --git a/tools/bpf/bpftool/btf.c b/tools/bpf/bpftool/btf.c index 7e6accb9d9f7..0744bd1150be 100644 --- a/tools/bpf/bpftool/btf.c +++ b/tools/bpf/bpftool/btf.c @@ -40,6 +40,7 @@ static const char * const btf_kind_str[NR_BTF_KINDS] = { [BTF_KIND_FLOAT] = "FLOAT", [BTF_KIND_DECL_TAG] = "DECL_TAG", [BTF_KIND_TYPE_TAG] = "TYPE_TAG", + [BTF_KIND_ENUM64] = "ENUM64", }; struct btf_attach_point { @@ -212,15 +213,18 @@ static int dump_btf_type(const struct btf *btf, __u32 id, case BTF_KIND_ENUM: { const struct btf_enum *v = (const void *)(t + 1); __u16 vlen = BTF_INFO_VLEN(t->info); + const char *encoding; int i; + encoding = btf_kflag(t) ? "SIGNED" : "UNSIGNED"; if (json_output) { + jsonw_string_field(w, "encoding", encoding); 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); + printf(" encoding=%s size=%u vlen=%u", encoding, t->size, vlen); } for (i = 0; i < vlen; i++, v++) { const char *name = btf_str(btf, v->name_off); @@ -228,10 +232,57 @@ static int dump_btf_type(const struct btf *btf, __u32 id, if (json_output) { jsonw_start_object(w); jsonw_string_field(w, "name", name); - jsonw_uint_field(w, "val", v->val); + if (btf_kflag(t)) + jsonw_int_field(w, "val", v->val); + else + jsonw_uint_field(w, "val", v->val); jsonw_end_object(w); } else { - printf("\n\t'%s' val=%u", name, v->val); + if (btf_kflag(t)) + printf("\n\t'%s' val=%d", name, v->val); + else + printf("\n\t'%s' val=%u", name, v->val); + } + } + if (json_output) + jsonw_end_array(w); + break; + } + case BTF_KIND_ENUM64: { + const struct btf_enum64 *v = btf_enum64(t); + __u16 vlen = btf_vlen(t); + const char *encoding; + int i; + + encoding = btf_kflag(t) ? "SIGNED" : "UNSIGNED"; + if (json_output) { + jsonw_string_field(w, "encoding", encoding); + jsonw_uint_field(w, "size", t->size); + jsonw_uint_field(w, "vlen", vlen); + jsonw_name(w, "values"); + jsonw_start_array(w); + } else { + printf(" encoding=%s size=%u vlen=%u", encoding, t->size, vlen); + } + for (i = 0; i < vlen; i++, v++) { + const char *name = btf_str(btf, v->name_off); + __u64 val = ((__u64)v->val_hi32 << 32) | v->val_lo32; + + if (json_output) { + jsonw_start_object(w); + jsonw_string_field(w, "name", name); + if (btf_kflag(t)) + jsonw_int_field(w, "val", val); + else + jsonw_uint_field(w, "val", val); + jsonw_end_object(w); + } else { + if (btf_kflag(t)) + printf("\n\t'%s' val=%lldLL", name, + (unsigned long long)val); + else + printf("\n\t'%s' val=%lluULL", name, + (unsigned long long)val); } } if (json_output) diff --git a/tools/bpf/bpftool/btf_dumper.c b/tools/bpf/bpftool/btf_dumper.c index f5dddf8ef404..125798b0bc5d 100644 --- a/tools/bpf/bpftool/btf_dumper.c +++ b/tools/bpf/bpftool/btf_dumper.c @@ -182,6 +182,32 @@ 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 val_lo32, val_hi32; + __u64 value; + __u16 i; + + value = *(__u64 *)data; + val_lo32 = (__u32)value; + val_hi32 = value >> 32; + + for (i = 0; i < btf_vlen(t); i++) { + if (val_lo32 == enums[i].val_lo32 && val_hi32 == enums[i].val_hi32) { + jsonw_string(d->jw, + btf__name_by_offset(d->btf, + enums[i].name_off)); + return 0; + } + } + + jsonw_int(d->jw, value); + return 0; +} + static bool is_str_array(const struct btf *btf, const struct btf_array *arr, const char *s) { @@ -542,6 +568,8 @@ static int btf_dumper_do_type(const struct btf_dumper *d, __u32 type_id, return btf_dumper_array(d, type_id, data); case BTF_KIND_ENUM: return btf_dumper_enum(d, t, data); + case BTF_KIND_ENUM64: + return btf_dumper_enum64(d, t, data); case BTF_KIND_PTR: btf_dumper_ptr(d, t, data); return 0; @@ -618,6 +646,7 @@ static int __btf_dumper_type_only(const struct btf *btf, __u32 type_id, btf__name_by_offset(btf, t->name_off)); break; case BTF_KIND_ENUM: + case BTF_KIND_ENUM64: BTF_PRINT_ARG("enum %s ", btf__name_by_offset(btf, t->name_off)); break; diff --git a/tools/bpf/bpftool/gen.c b/tools/bpf/bpftool/gen.c index f158dc1c2149..480cbd859359 100644 --- a/tools/bpf/bpftool/gen.c +++ b/tools/bpf/bpftool/gen.c @@ -1750,6 +1750,7 @@ btfgen_mark_type(struct btfgen_info *info, unsigned int type_id, bool follow_poi case BTF_KIND_INT: case BTF_KIND_FLOAT: case BTF_KIND_ENUM: + case BTF_KIND_ENUM64: case BTF_KIND_STRUCT: case BTF_KIND_UNION: break;