| Message ID | 20220501190028.2579037-1-yhs@fb.com (mailing list archive) |
|---|---|
| State | Superseded |
| Delegated to: | BPF |
| Headers | show |
| Series | bpf: Add 64bit enum value support | expand |
On Sun, May 1, 2022 at 12:00 PM Yonghong Song <yhs@fb.com> 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? > }; > ... > > The 64bit value is represented properly in BTF and C dump. > > Signed-off-by: Yonghong Song <yhs@fb.com> > --- just minor nits, LGTM Acked-by: Andrii Nakryiko <andrii@kernel.org> > 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) > + 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; () ? > + > + 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 > + > + value = *(__u64 *)data; > + hi32 = value >> 32; > + lo32 = (__u32)value; > + [...]
On 5/9/22 4:31 PM, Andrii Nakryiko wrote: > On Sun, May 1, 2022 at 12:00 PM Yonghong Song <yhs@fb.com> 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@fb.com> >> --- > > just minor nits, LGTM > > Acked-by: Andrii Nakryiko <andrii@kernel.org> > >> 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; >> + > > [...]
diff --git a/tools/bpf/bpftool/btf.c b/tools/bpf/bpftool/btf.c index a2c665beda87..ae3c413fa3b1 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 { @@ -228,10 +229,52 @@ 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_uint_field(w, "val", v->val); + else + jsonw_int_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=%u", name, v->val); + else + printf("\n\t'%s' val=%d", name, v->val); + } + } + if (json_output) + jsonw_end_array(w); + break; + } + case BTF_KIND_ENUM64: { + const struct btf_enum64 *v = (const void *)(t + 1); + __u16 vlen = BTF_INFO_VLEN(t->info); + 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; + + 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; + + value = *(__u64 *)data; + hi32 = value >> 32; + lo32 = (__u32)value; + + for (i = 0; i < btf_vlen(t); i++) { + if (hi32 == enums[i].hi32 && lo32 == enums[i].lo32) { + 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 +571,8 @@ 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 +649,7 @@ 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 7678af364793..b80c3577057f 100644 --- a/tools/bpf/bpftool/gen.c +++ b/tools/bpf/bpftool/gen.c @@ -1746,6 +1746,7 @@ 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;
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, }; ... The 64bit value is represented properly in BTF and C dump. Signed-off-by: Yonghong Song <yhs@fb.com> --- 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(-)