Message ID | 20230419003651.988865-1-kuifeng@meta.com (mailing list archive) |
---|---|
State | Superseded |
Delegated to: | BPF |
Headers | show |
Series | [bpf-next,v2] bpftool: Show map IDs along with struct_ops links. | expand |
On Wed, 19 Apr 2023 at 01:37, Kui-Feng Lee <thinker.li@gmail.com> wrote: > > A new link type, BPF_LINK_TYPE_STRUCT_OPS, was added to attach > struct_ops to links. (226bc6ae6405) It would be helpful for users to > know which map is associated with the link. > > The assumption was that every link is associated with a BPF program, but > this does not hold true for struct_ops. It would be better to display > map_id instead of prog_id for struct_ops links. However, some tools may > rely on the old assumption and need a prog_id. The discussion on the > mailing list suggests that tools should parse JSON format. We will maintain > the existing JSON format by adding a map_id without removing prog_id. As > for plain text format, we will remove prog_id from the header line and add > a map_id for struct_ops links. > > Signed-off-by: Kui-Feng Lee <kuifeng@meta.com> > Reviewed-by: Quentin Monnet <quentin@isovalent.com> Looks all good from my side, thank you.
Thank you for reviewing this. On 4/19/23 16:25, Quentin Monnet wrote: > On Wed, 19 Apr 2023 at 01:37, Kui-Feng Lee <thinker.li@gmail.com> wrote: >> >> A new link type, BPF_LINK_TYPE_STRUCT_OPS, was added to attach >> struct_ops to links. (226bc6ae6405) It would be helpful for users to >> know which map is associated with the link. >> >> The assumption was that every link is associated with a BPF program, but >> this does not hold true for struct_ops. It would be better to display >> map_id instead of prog_id for struct_ops links. However, some tools may >> rely on the old assumption and need a prog_id. The discussion on the >> mailing list suggests that tools should parse JSON format. We will maintain >> the existing JSON format by adding a map_id without removing prog_id. As >> for plain text format, we will remove prog_id from the header line and add >> a map_id for struct_ops links. >> >> Signed-off-by: Kui-Feng Lee <kuifeng@meta.com> >> Reviewed-by: Quentin Monnet <quentin@isovalent.com> > > Looks all good from my side, thank you.
On Tue, Apr 18, 2023 at 5:37 PM Kui-Feng Lee <thinker.li@gmail.com> wrote: > > A new link type, BPF_LINK_TYPE_STRUCT_OPS, was added to attach > struct_ops to links. (226bc6ae6405) It would be helpful for users to > know which map is associated with the link. > > The assumption was that every link is associated with a BPF program, but > this does not hold true for struct_ops. It would be better to display > map_id instead of prog_id for struct_ops links. However, some tools may > rely on the old assumption and need a prog_id. The discussion on the > mailing list suggests that tools should parse JSON format. We will maintain > the existing JSON format by adding a map_id without removing prog_id. As > for plain text format, we will remove prog_id from the header line and add > a map_id for struct_ops links. > > Signed-off-by: Kui-Feng Lee <kuifeng@meta.com> > Reviewed-by: Quentin Monnet <quentin@isovalent.com> > --- > tools/bpf/bpftool/link.c | 9 ++++++++- > 1 file changed, 8 insertions(+), 1 deletion(-) > > diff --git a/tools/bpf/bpftool/link.c b/tools/bpf/bpftool/link.c > index f985b79cca27..8eb8520bd7b4 100644 > --- a/tools/bpf/bpftool/link.c > +++ b/tools/bpf/bpftool/link.c > @@ -195,6 +195,10 @@ static int show_link_close_json(int fd, struct bpf_link_info *info) > info->netns.netns_ino); > show_link_attach_type_json(info->netns.attach_type, json_wtr); > break; > + case BPF_LINK_TYPE_STRUCT_OPS: > + jsonw_uint_field(json_wtr, "map_id", > + info->struct_ops.map_id); > + break; > default: > break; > } > @@ -227,7 +231,10 @@ static void show_link_header_plain(struct bpf_link_info *info) > else > printf("type %u ", info->type); > > - printf("prog %u ", info->prog_id); > + if (info->type == BPF_LINK_TYPE_STRUCT_OPS) > + printf("map_id %u ", info->struct_ops.map_id); > + else > + printf("prog %u ", info->prog_id); if we output "prog %u" for prog_id, shouldn't we just output "map %u" for map_id? > } > > static void show_link_attach_type_plain(__u32 attach_type) > -- > 2.34.1 >
On 4/20/23 16:41, Andrii Nakryiko wrote: > On Tue, Apr 18, 2023 at 5:37 PM Kui-Feng Lee <thinker.li@gmail.com> wrote: >> >> A new link type, BPF_LINK_TYPE_STRUCT_OPS, was added to attach >> struct_ops to links. (226bc6ae6405) It would be helpful for users to >> know which map is associated with the link. >> >> The assumption was that every link is associated with a BPF program, but >> this does not hold true for struct_ops. It would be better to display >> map_id instead of prog_id for struct_ops links. However, some tools may >> rely on the old assumption and need a prog_id. The discussion on the >> mailing list suggests that tools should parse JSON format. We will maintain >> the existing JSON format by adding a map_id without removing prog_id. As >> for plain text format, we will remove prog_id from the header line and add >> a map_id for struct_ops links. >> >> Signed-off-by: Kui-Feng Lee <kuifeng@meta.com> >> Reviewed-by: Quentin Monnet <quentin@isovalent.com> >> --- >> tools/bpf/bpftool/link.c | 9 ++++++++- >> 1 file changed, 8 insertions(+), 1 deletion(-) >> >> diff --git a/tools/bpf/bpftool/link.c b/tools/bpf/bpftool/link.c >> index f985b79cca27..8eb8520bd7b4 100644 >> --- a/tools/bpf/bpftool/link.c >> +++ b/tools/bpf/bpftool/link.c >> @@ -195,6 +195,10 @@ static int show_link_close_json(int fd, struct bpf_link_info *info) >> info->netns.netns_ino); >> show_link_attach_type_json(info->netns.attach_type, json_wtr); >> break; >> + case BPF_LINK_TYPE_STRUCT_OPS: >> + jsonw_uint_field(json_wtr, "map_id", >> + info->struct_ops.map_id); >> + break; >> default: >> break; >> } >> @@ -227,7 +231,10 @@ static void show_link_header_plain(struct bpf_link_info *info) >> else >> printf("type %u ", info->type); >> >> - printf("prog %u ", info->prog_id); >> + if (info->type == BPF_LINK_TYPE_STRUCT_OPS) >> + printf("map_id %u ", info->struct_ops.map_id); >> + else >> + printf("prog %u ", info->prog_id); > > if we output "prog %u" for prog_id, shouldn't we just output "map %u" > for map_id? "map" make sense to me. > >> } >> >> static void show_link_attach_type_plain(__u32 attach_type) >> -- >> 2.34.1 >>
diff --git a/tools/bpf/bpftool/link.c b/tools/bpf/bpftool/link.c index f985b79cca27..8eb8520bd7b4 100644 --- a/tools/bpf/bpftool/link.c +++ b/tools/bpf/bpftool/link.c @@ -195,6 +195,10 @@ static int show_link_close_json(int fd, struct bpf_link_info *info) info->netns.netns_ino); show_link_attach_type_json(info->netns.attach_type, json_wtr); break; + case BPF_LINK_TYPE_STRUCT_OPS: + jsonw_uint_field(json_wtr, "map_id", + info->struct_ops.map_id); + break; default: break; } @@ -227,7 +231,10 @@ static void show_link_header_plain(struct bpf_link_info *info) else printf("type %u ", info->type); - printf("prog %u ", info->prog_id); + if (info->type == BPF_LINK_TYPE_STRUCT_OPS) + printf("map_id %u ", info->struct_ops.map_id); + else + printf("prog %u ", info->prog_id); } static void show_link_attach_type_plain(__u32 attach_type)