| Message ID | 20200801084721.1812607-3-songliubraving@fb.com |
|---|---|
| State | Changes Requested |
| Delegated to: | BPF Maintainers |
| Headers | show |
| Series | introduce BPF_PROG_TYPE_USER | expand |
On Sat, Aug 1, 2020 at 1:50 AM Song Liu <songliubraving@fb.com> wrote: > > Add cpu_plus to bpf_prog_test_run_attr. Add BPF_PROG_SEC "user" for > BPF_PROG_TYPE_USER programs. > > Signed-off-by: Song Liu <songliubraving@fb.com> > --- > tools/lib/bpf/bpf.c | 1 + > tools/lib/bpf/bpf.h | 3 +++ > tools/lib/bpf/libbpf.c | 1 + > tools/lib/bpf/libbpf_probes.c | 1 + > 4 files changed, 6 insertions(+) > > diff --git a/tools/lib/bpf/bpf.c b/tools/lib/bpf/bpf.c > index e1bdf214f75fe..b28c3daa9c270 100644 > --- a/tools/lib/bpf/bpf.c > +++ b/tools/lib/bpf/bpf.c > @@ -693,6 +693,7 @@ int bpf_prog_test_run_xattr(struct bpf_prog_test_run_attr *test_attr) > attr.test.ctx_size_in = test_attr->ctx_size_in; > attr.test.ctx_size_out = test_attr->ctx_size_out; > attr.test.repeat = test_attr->repeat; > + attr.test.cpu_plus = test_attr->cpu_plus; > > ret = sys_bpf(BPF_PROG_TEST_RUN, &attr, sizeof(attr)); > test_attr->data_size_out = attr.test.data_size_out; > diff --git a/tools/lib/bpf/bpf.h b/tools/lib/bpf/bpf.h > index 6d367e01d05e9..0c799740df566 100644 > --- a/tools/lib/bpf/bpf.h > +++ b/tools/lib/bpf/bpf.h > @@ -205,6 +205,9 @@ struct bpf_prog_test_run_attr { > void *ctx_out; /* optional */ > __u32 ctx_size_out; /* in: max length of ctx_out > * out: length of cxt_out */ > + __u32 cpu_plus; /* specify which cpu to run the test with > + * cpu_plus = cpu_id + 1. > + * If cpu_plus = 0, run on current cpu */ We can't do this due to ABI guarantees. We'll have to add a new API using OPTS arguments. > }; > > LIBBPF_API int bpf_prog_test_run_xattr(struct bpf_prog_test_run_attr *test_attr); > diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c > index b9f11f854985b..9ce175a486214 100644 > --- a/tools/lib/bpf/libbpf.c > +++ b/tools/lib/bpf/libbpf.c > @@ -6922,6 +6922,7 @@ static const struct bpf_sec_def section_defs[] = { > BPF_PROG_SEC("lwt_out", BPF_PROG_TYPE_LWT_OUT), > BPF_PROG_SEC("lwt_xmit", BPF_PROG_TYPE_LWT_XMIT), > BPF_PROG_SEC("lwt_seg6local", BPF_PROG_TYPE_LWT_SEG6LOCAL), > + BPF_PROG_SEC("user", BPF_PROG_TYPE_USER), let's do "user/" for consistency with most other prog types (and nice separation between prog type and custom user name) > BPF_APROG_SEC("cgroup_skb/ingress", BPF_PROG_TYPE_CGROUP_SKB, > BPF_CGROUP_INET_INGRESS), > BPF_APROG_SEC("cgroup_skb/egress", BPF_PROG_TYPE_CGROUP_SKB, > diff --git a/tools/lib/bpf/libbpf_probes.c b/tools/lib/bpf/libbpf_probes.c > index 5a3d3f0784081..163013084000e 100644 > --- a/tools/lib/bpf/libbpf_probes.c > +++ b/tools/lib/bpf/libbpf_probes.c > @@ -112,6 +112,7 @@ probe_load(enum bpf_prog_type prog_type, const struct bpf_insn *insns, > case BPF_PROG_TYPE_STRUCT_OPS: > case BPF_PROG_TYPE_EXT: > case BPF_PROG_TYPE_LSM: > + case BPF_PROG_TYPE_USER: > default: > break; > } > -- > 2.24.1 >
> On Aug 2, 2020, at 6:40 PM, Andrii Nakryiko <andrii.nakryiko@gmail.com> wrote: > > On Sat, Aug 1, 2020 at 1:50 AM Song Liu <songliubraving@fb.com> wrote: >> >> Add cpu_plus to bpf_prog_test_run_attr. Add BPF_PROG_SEC "user" for >> BPF_PROG_TYPE_USER programs. >> >> Signed-off-by: Song Liu <songliubraving@fb.com> >> --- >> tools/lib/bpf/bpf.c | 1 + >> tools/lib/bpf/bpf.h | 3 +++ >> tools/lib/bpf/libbpf.c | 1 + >> tools/lib/bpf/libbpf_probes.c | 1 + >> 4 files changed, 6 insertions(+) >> >> diff --git a/tools/lib/bpf/bpf.c b/tools/lib/bpf/bpf.c >> index e1bdf214f75fe..b28c3daa9c270 100644 >> --- a/tools/lib/bpf/bpf.c >> +++ b/tools/lib/bpf/bpf.c >> @@ -693,6 +693,7 @@ int bpf_prog_test_run_xattr(struct bpf_prog_test_run_attr *test_attr) >> attr.test.ctx_size_in = test_attr->ctx_size_in; >> attr.test.ctx_size_out = test_attr->ctx_size_out; >> attr.test.repeat = test_attr->repeat; >> + attr.test.cpu_plus = test_attr->cpu_plus; >> >> ret = sys_bpf(BPF_PROG_TEST_RUN, &attr, sizeof(attr)); >> test_attr->data_size_out = attr.test.data_size_out; >> diff --git a/tools/lib/bpf/bpf.h b/tools/lib/bpf/bpf.h >> index 6d367e01d05e9..0c799740df566 100644 >> --- a/tools/lib/bpf/bpf.h >> +++ b/tools/lib/bpf/bpf.h >> @@ -205,6 +205,9 @@ struct bpf_prog_test_run_attr { >> void *ctx_out; /* optional */ >> __u32 ctx_size_out; /* in: max length of ctx_out >> * out: length of cxt_out */ >> + __u32 cpu_plus; /* specify which cpu to run the test with >> + * cpu_plus = cpu_id + 1. >> + * If cpu_plus = 0, run on current cpu */ > > We can't do this due to ABI guarantees. We'll have to add a new API > using OPTS arguments. To make sure I understand this correctly, the concern is when we compile the binary with one version of libbpf and run it with libbpf.so of a different version, right? Thanks, Song > >> }; >> >> LIBBPF_API int bpf_prog_test_run_xattr(struct bpf_prog_test_run_attr *test_attr); >> diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c >> index b9f11f854985b..9ce175a486214 100644 >> --- a/tools/lib/bpf/libbpf.c >> +++ b/tools/lib/bpf/libbpf.c >> @@ -6922,6 +6922,7 @@ static const struct bpf_sec_def section_defs[] = { >> BPF_PROG_SEC("lwt_out", BPF_PROG_TYPE_LWT_OUT), >> BPF_PROG_SEC("lwt_xmit", BPF_PROG_TYPE_LWT_XMIT), >> BPF_PROG_SEC("lwt_seg6local", BPF_PROG_TYPE_LWT_SEG6LOCAL), >> + BPF_PROG_SEC("user", BPF_PROG_TYPE_USER), > > let's do "user/" for consistency with most other prog types (and nice > separation between prog type and custom user name) Will update.
On Sun, Aug 2, 2020 at 9:21 PM Song Liu <songliubraving@fb.com> wrote: > > > > > On Aug 2, 2020, at 6:40 PM, Andrii Nakryiko <andrii.nakryiko@gmail.com> wrote: > > > > On Sat, Aug 1, 2020 at 1:50 AM Song Liu <songliubraving@fb.com> wrote: > >> > >> Add cpu_plus to bpf_prog_test_run_attr. Add BPF_PROG_SEC "user" for > >> BPF_PROG_TYPE_USER programs. > >> > >> Signed-off-by: Song Liu <songliubraving@fb.com> > >> --- > >> tools/lib/bpf/bpf.c | 1 + > >> tools/lib/bpf/bpf.h | 3 +++ > >> tools/lib/bpf/libbpf.c | 1 + > >> tools/lib/bpf/libbpf_probes.c | 1 + > >> 4 files changed, 6 insertions(+) > >> > >> diff --git a/tools/lib/bpf/bpf.c b/tools/lib/bpf/bpf.c > >> index e1bdf214f75fe..b28c3daa9c270 100644 > >> --- a/tools/lib/bpf/bpf.c > >> +++ b/tools/lib/bpf/bpf.c > >> @@ -693,6 +693,7 @@ int bpf_prog_test_run_xattr(struct bpf_prog_test_run_attr *test_attr) > >> attr.test.ctx_size_in = test_attr->ctx_size_in; > >> attr.test.ctx_size_out = test_attr->ctx_size_out; > >> attr.test.repeat = test_attr->repeat; > >> + attr.test.cpu_plus = test_attr->cpu_plus; > >> > >> ret = sys_bpf(BPF_PROG_TEST_RUN, &attr, sizeof(attr)); > >> test_attr->data_size_out = attr.test.data_size_out; > >> diff --git a/tools/lib/bpf/bpf.h b/tools/lib/bpf/bpf.h > >> index 6d367e01d05e9..0c799740df566 100644 > >> --- a/tools/lib/bpf/bpf.h > >> +++ b/tools/lib/bpf/bpf.h > >> @@ -205,6 +205,9 @@ struct bpf_prog_test_run_attr { > >> void *ctx_out; /* optional */ > >> __u32 ctx_size_out; /* in: max length of ctx_out > >> * out: length of cxt_out */ > >> + __u32 cpu_plus; /* specify which cpu to run the test with > >> + * cpu_plus = cpu_id + 1. > >> + * If cpu_plus = 0, run on current cpu */ > > > > We can't do this due to ABI guarantees. We'll have to add a new API > > using OPTS arguments. > > To make sure I understand this correctly, the concern is when we compile > the binary with one version of libbpf and run it with libbpf.so of a > different version, right? > yep, exactly > Thanks, > Song > > > > >> }; > >> > >> LIBBPF_API int bpf_prog_test_run_xattr(struct bpf_prog_test_run_attr *test_attr); > >> diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c > >> index b9f11f854985b..9ce175a486214 100644 > >> --- a/tools/lib/bpf/libbpf.c > >> +++ b/tools/lib/bpf/libbpf.c > >> @@ -6922,6 +6922,7 @@ static const struct bpf_sec_def section_defs[] = { > >> BPF_PROG_SEC("lwt_out", BPF_PROG_TYPE_LWT_OUT), > >> BPF_PROG_SEC("lwt_xmit", BPF_PROG_TYPE_LWT_XMIT), > >> BPF_PROG_SEC("lwt_seg6local", BPF_PROG_TYPE_LWT_SEG6LOCAL), > >> + BPF_PROG_SEC("user", BPF_PROG_TYPE_USER), > > > > let's do "user/" for consistency with most other prog types (and nice > > separation between prog type and custom user name) > > Will update. > thanks!
> On Aug 2, 2020, at 6:40 PM, Andrii Nakryiko <andrii.nakryiko@gmail.com> wrote: > > On Sat, Aug 1, 2020 at 1:50 AM Song Liu <songliubraving@fb.com> wrote: >> [...] > >> }; >> >> LIBBPF_API int bpf_prog_test_run_xattr(struct bpf_prog_test_run_attr *test_attr); >> diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c >> index b9f11f854985b..9ce175a486214 100644 >> --- a/tools/lib/bpf/libbpf.c >> +++ b/tools/lib/bpf/libbpf.c >> @@ -6922,6 +6922,7 @@ static const struct bpf_sec_def section_defs[] = { >> BPF_PROG_SEC("lwt_out", BPF_PROG_TYPE_LWT_OUT), >> BPF_PROG_SEC("lwt_xmit", BPF_PROG_TYPE_LWT_XMIT), >> BPF_PROG_SEC("lwt_seg6local", BPF_PROG_TYPE_LWT_SEG6LOCAL), >> + BPF_PROG_SEC("user", BPF_PROG_TYPE_USER), > > let's do "user/" for consistency with most other prog types (and nice > separation between prog type and custom user name) About "user" vs. "user/", I still think "user" is better. Unlike kprobe and tracepoint, user prog doesn't use the part after "/". This is similar to "perf_event" for BPF_PROG_TYPE_PERF_EVENT, "xdl" for BPF_PROG_TYPE_XDP, etc. If we specify "user" here, "user/" and "user/xxx" would also work. However, if we specify "user/" here, programs that used "user" by accident will fail to load, with a message like: libbpf: failed to load program 'user' which is confusing. Thanks, Song [...]
On Mon, Aug 3, 2020 at 6:18 PM Song Liu <songliubraving@fb.com> wrote: > > > > > On Aug 2, 2020, at 6:40 PM, Andrii Nakryiko <andrii.nakryiko@gmail.com> wrote: > > > > On Sat, Aug 1, 2020 at 1:50 AM Song Liu <songliubraving@fb.com> wrote: > >> > > [...] > > > > >> }; > >> > >> LIBBPF_API int bpf_prog_test_run_xattr(struct bpf_prog_test_run_attr *test_attr); > >> diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c > >> index b9f11f854985b..9ce175a486214 100644 > >> --- a/tools/lib/bpf/libbpf.c > >> +++ b/tools/lib/bpf/libbpf.c > >> @@ -6922,6 +6922,7 @@ static const struct bpf_sec_def section_defs[] = { > >> BPF_PROG_SEC("lwt_out", BPF_PROG_TYPE_LWT_OUT), > >> BPF_PROG_SEC("lwt_xmit", BPF_PROG_TYPE_LWT_XMIT), > >> BPF_PROG_SEC("lwt_seg6local", BPF_PROG_TYPE_LWT_SEG6LOCAL), > >> + BPF_PROG_SEC("user", BPF_PROG_TYPE_USER), > > > > let's do "user/" for consistency with most other prog types (and nice > > separation between prog type and custom user name) > > About "user" vs. "user/", I still think "user" is better. > > Unlike kprobe and tracepoint, user prog doesn't use the part after "/". > This is similar to "perf_event" for BPF_PROG_TYPE_PERF_EVENT, "xdl" for > BPF_PROG_TYPE_XDP, etc. If we specify "user" here, "user/" and "user/xxx" > would also work. However, if we specify "user/" here, programs that used > "user" by accident will fail to load, with a message like: > > libbpf: failed to load program 'user' > > which is confusing. xdp, perf_event and a bunch of others don't enforce it, that's true, they are a bit of a legacy, unfortunately. But all the recent ones do, and we explicitly did that for xdp_dev/xdp_cpu, for instance. Specifying just "user" in the spec would allow something nonsensical like "userargh", for instance, due to this being treated as a prefix. There is no harm to require users to do "user/my_prog", though. Alternatively, we could introduce a new convention in the spec, something like "user?", which would accept either "user" or "user/something", but not "user/" nor "userblah". We can try that as well. > > Thanks, > Song > > [...] >
> On Aug 4, 2020, at 6:38 PM, Andrii Nakryiko <andrii.nakryiko@gmail.com> wrote: > > On Mon, Aug 3, 2020 at 6:18 PM Song Liu <songliubraving@fb.com> wrote: >> >> >> >>> On Aug 2, 2020, at 6:40 PM, Andrii Nakryiko <andrii.nakryiko@gmail.com> wrote: >>> >>> On Sat, Aug 1, 2020 at 1:50 AM Song Liu <songliubraving@fb.com> wrote: >>>> >> >> [...] >> >>> >>>> }; >>>> >>>> LIBBPF_API int bpf_prog_test_run_xattr(struct bpf_prog_test_run_attr *test_attr); >>>> diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c >>>> index b9f11f854985b..9ce175a486214 100644 >>>> --- a/tools/lib/bpf/libbpf.c >>>> +++ b/tools/lib/bpf/libbpf.c >>>> @@ -6922,6 +6922,7 @@ static const struct bpf_sec_def section_defs[] = { >>>> BPF_PROG_SEC("lwt_out", BPF_PROG_TYPE_LWT_OUT), >>>> BPF_PROG_SEC("lwt_xmit", BPF_PROG_TYPE_LWT_XMIT), >>>> BPF_PROG_SEC("lwt_seg6local", BPF_PROG_TYPE_LWT_SEG6LOCAL), >>>> + BPF_PROG_SEC("user", BPF_PROG_TYPE_USER), >>> >>> let's do "user/" for consistency with most other prog types (and nice >>> separation between prog type and custom user name) >> >> About "user" vs. "user/", I still think "user" is better. >> >> Unlike kprobe and tracepoint, user prog doesn't use the part after "/". >> This is similar to "perf_event" for BPF_PROG_TYPE_PERF_EVENT, "xdl" for >> BPF_PROG_TYPE_XDP, etc. If we specify "user" here, "user/" and "user/xxx" >> would also work. However, if we specify "user/" here, programs that used >> "user" by accident will fail to load, with a message like: >> >> libbpf: failed to load program 'user' >> >> which is confusing. > > xdp, perf_event and a bunch of others don't enforce it, that's true, > they are a bit of a legacy, I don't see w/o "/" is a legacy thing. BPF_PROG_TYPE_STRUCT_OPS just uses "struct_ops". > unfortunately. But all the recent ones do, > and we explicitly did that for xdp_dev/xdp_cpu, for instance. > Specifying just "user" in the spec would allow something nonsensical > like "userargh", for instance, due to this being treated as a prefix. > There is no harm to require users to do "user/my_prog", though. I don't see why allowing "userargh" is a problem. Failing "user" is more confusing. We can probably improve that by a hint like: libbpf: failed to load program 'user', do you mean "user/"? But it is pretty silly. "user/something_never_used" also looks weird. > Alternatively, we could introduce a new convention in the spec, > something like "user?", which would accept either "user" or > "user/something", but not "user/" nor "userblah". We can try that as > well. Again, I don't really understand why allowing "userblah" is a problem. We already have "xdp", "xdp_devmap/", and "xdp_cpumap/", they all work fine so far. Thanks, Song
On Tue, Aug 4, 2020 at 8:59 PM Song Liu <songliubraving@fb.com> wrote: > > > > > On Aug 4, 2020, at 6:38 PM, Andrii Nakryiko <andrii.nakryiko@gmail.com> wrote: > > > > On Mon, Aug 3, 2020 at 6:18 PM Song Liu <songliubraving@fb.com> wrote: > >> > >> > >> > >>> On Aug 2, 2020, at 6:40 PM, Andrii Nakryiko <andrii.nakryiko@gmail.com> wrote: > >>> > >>> On Sat, Aug 1, 2020 at 1:50 AM Song Liu <songliubraving@fb.com> wrote: > >>>> > >> > >> [...] > >> > >>> > >>>> }; > >>>> > >>>> LIBBPF_API int bpf_prog_test_run_xattr(struct bpf_prog_test_run_attr *test_attr); > >>>> diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c > >>>> index b9f11f854985b..9ce175a486214 100644 > >>>> --- a/tools/lib/bpf/libbpf.c > >>>> +++ b/tools/lib/bpf/libbpf.c > >>>> @@ -6922,6 +6922,7 @@ static const struct bpf_sec_def section_defs[] = { > >>>> BPF_PROG_SEC("lwt_out", BPF_PROG_TYPE_LWT_OUT), > >>>> BPF_PROG_SEC("lwt_xmit", BPF_PROG_TYPE_LWT_XMIT), > >>>> BPF_PROG_SEC("lwt_seg6local", BPF_PROG_TYPE_LWT_SEG6LOCAL), > >>>> + BPF_PROG_SEC("user", BPF_PROG_TYPE_USER), > >>> > >>> let's do "user/" for consistency with most other prog types (and nice > >>> separation between prog type and custom user name) > >> > >> About "user" vs. "user/", I still think "user" is better. > >> > >> Unlike kprobe and tracepoint, user prog doesn't use the part after "/". > >> This is similar to "perf_event" for BPF_PROG_TYPE_PERF_EVENT, "xdl" for > >> BPF_PROG_TYPE_XDP, etc. If we specify "user" here, "user/" and "user/xxx" > >> would also work. However, if we specify "user/" here, programs that used > >> "user" by accident will fail to load, with a message like: > >> > >> libbpf: failed to load program 'user' > >> > >> which is confusing. > > > > xdp, perf_event and a bunch of others don't enforce it, that's true, > > they are a bit of a legacy, > > I don't see w/o "/" is a legacy thing. BPF_PROG_TYPE_STRUCT_OPS just uses > "struct_ops". > > > unfortunately. But all the recent ones do, > > and we explicitly did that for xdp_dev/xdp_cpu, for instance. > > Specifying just "user" in the spec would allow something nonsensical > > like "userargh", for instance, due to this being treated as a prefix. > > There is no harm to require users to do "user/my_prog", though. > > I don't see why allowing "userargh" is a problem. Failing "user" is > more confusing. We can probably improve that by a hint like: > > libbpf: failed to load program 'user', do you mean "user/"? > > But it is pretty silly. "user/something_never_used" also looks weird. "userargh" is terrible, IMO. It's a different identifier that just happens to have the first 4 letters matching "user" program type. There must be either a standardized separator (which happens to be '/') or none. See the suggestion below. > > > Alternatively, we could introduce a new convention in the spec, > > something like "user?", which would accept either "user" or > > "user/something", but not "user/" nor "userblah". We can try that as > > well. > > Again, I don't really understand why allowing "userblah" is a problem. > We already have "xdp", "xdp_devmap/", and "xdp_cpumap/", they all work > fine so far. Right, we have "xdp_devmap/" and "xdp_cpumap/", as you say. I haven't seen so much pushback against trailing forward slash with those ;) But anyways, as part of deprecating APIs and preparing libbpf for 1.0 release over this half, I think I'm going to emit warnings for names like "prog_type_whatever" or "prog_typeevenworse", etc. And asking users to normalize section names to either "prog_type" or "prog_type/something/here", whichever makes sense for a specific program type. Right now libbpf doesn't allow two separate BPF programs with the same section name, so enforcing strict "user" is limiting to users. We are going to lift that restriction pretty soon, though. But for now, please stick with what we've been doing lately and mark it as "user/", later we'll allow just "user" as well. > > Thanks, > Song
> On Aug 4, 2020, at 10:32 PM, Andrii Nakryiko <andrii.nakryiko@gmail.com> wrote: > > On Tue, Aug 4, 2020 at 8:59 PM Song Liu <songliubraving@fb.com> wrote: >> >> >> >>> On Aug 4, 2020, at 6:38 PM, Andrii Nakryiko <andrii.nakryiko@gmail.com> wrote: >>> >>> On Mon, Aug 3, 2020 at 6:18 PM Song Liu <songliubraving@fb.com> wrote: >>>> >>>> >>>> >>>>> On Aug 2, 2020, at 6:40 PM, Andrii Nakryiko <andrii.nakryiko@gmail.com> wrote: >>>>> >>>>> On Sat, Aug 1, 2020 at 1:50 AM Song Liu <songliubraving@fb.com> wrote: >>>>>> >>>> >>>> [...] >>>> >>>>> >>>>>> }; >>>>>> >>>>>> LIBBPF_API int bpf_prog_test_run_xattr(struct bpf_prog_test_run_attr *test_attr); >>>>>> diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c >>>>>> index b9f11f854985b..9ce175a486214 100644 >>>>>> --- a/tools/lib/bpf/libbpf.c >>>>>> +++ b/tools/lib/bpf/libbpf.c >>>>>> @@ -6922,6 +6922,7 @@ static const struct bpf_sec_def section_defs[] = { >>>>>> BPF_PROG_SEC("lwt_out", BPF_PROG_TYPE_LWT_OUT), >>>>>> BPF_PROG_SEC("lwt_xmit", BPF_PROG_TYPE_LWT_XMIT), >>>>>> BPF_PROG_SEC("lwt_seg6local", BPF_PROG_TYPE_LWT_SEG6LOCAL), >>>>>> + BPF_PROG_SEC("user", BPF_PROG_TYPE_USER), >>>>> >>>>> let's do "user/" for consistency with most other prog types (and nice >>>>> separation between prog type and custom user name) >>>> >>>> About "user" vs. "user/", I still think "user" is better. >>>> >>>> Unlike kprobe and tracepoint, user prog doesn't use the part after "/". >>>> This is similar to "perf_event" for BPF_PROG_TYPE_PERF_EVENT, "xdl" for >>>> BPF_PROG_TYPE_XDP, etc. If we specify "user" here, "user/" and "user/xxx" >>>> would also work. However, if we specify "user/" here, programs that used >>>> "user" by accident will fail to load, with a message like: >>>> >>>> libbpf: failed to load program 'user' >>>> >>>> which is confusing. >>> >>> xdp, perf_event and a bunch of others don't enforce it, that's true, >>> they are a bit of a legacy, >> >> I don't see w/o "/" is a legacy thing. BPF_PROG_TYPE_STRUCT_OPS just uses >> "struct_ops". >> >>> unfortunately. But all the recent ones do, >>> and we explicitly did that for xdp_dev/xdp_cpu, for instance. >>> Specifying just "user" in the spec would allow something nonsensical >>> like "userargh", for instance, due to this being treated as a prefix. >>> There is no harm to require users to do "user/my_prog", though. >> >> I don't see why allowing "userargh" is a problem. Failing "user" is >> more confusing. We can probably improve that by a hint like: >> >> libbpf: failed to load program 'user', do you mean "user/"? >> >> But it is pretty silly. "user/something_never_used" also looks weird. > > "userargh" is terrible, IMO. It's a different identifier that just > happens to have the first 4 letters matching "user" program type. > There must be either a standardized separator (which happens to be > '/') or none. See the suggestion below. We have no problem deal with "a different identifier that just happens to have the first letters matching", like xdp vs. xdp_devmap and xdp_cpumap, right? >> >>> Alternatively, we could introduce a new convention in the spec, >>> something like "user?", which would accept either "user" or >>> "user/something", but not "user/" nor "userblah". We can try that as >>> well. >> >> Again, I don't really understand why allowing "userblah" is a problem. >> We already have "xdp", "xdp_devmap/", and "xdp_cpumap/", they all work >> fine so far. > > Right, we have "xdp_devmap/" and "xdp_cpumap/", as you say. I haven't > seen so much pushback against trailing forward slash with those ;) I haven't seen any issue with old "perf_event", "xdp" and new "struct_ops" either. > > But anyways, as part of deprecating APIs and preparing libbpf for 1.0 > release over this half, I think I'm going to emit warnings for names > like "prog_type_whatever" or "prog_typeevenworse", etc. And asking > users to normalize section names to either "prog_type" or > "prog_type/something/here", whichever makes sense for a specific > program type. Exactly, "user" makes sense here; while "kprobe/__set_task_comm" makes sense for kprobe. > Right now libbpf doesn't allow two separate BPF programs > with the same section name, so enforcing strict "user" is limiting to > users. We are going to lift that restriction pretty soon, though. But > for now, please stick with what we've been doing lately and mark it as > "user/", later we'll allow just "user" as well. Since we would allow "user" later, why we have to reject it for now? Imagine the user just compiled and booted into a new kernel with user program support; and then got the following message: libbpf: failed to load program 'user' If I were the user, I would definitely question whether the kernel was correct...
On Tue, Aug 4, 2020 at 11:26 PM Song Liu <songliubraving@fb.com> wrote: > > > > > On Aug 4, 2020, at 10:32 PM, Andrii Nakryiko <andrii.nakryiko@gmail.com> wrote: > > > > On Tue, Aug 4, 2020 at 8:59 PM Song Liu <songliubraving@fb.com> wrote: > >> > >> > >> > >>> On Aug 4, 2020, at 6:38 PM, Andrii Nakryiko <andrii.nakryiko@gmail.com> wrote: > >>> > >>> On Mon, Aug 3, 2020 at 6:18 PM Song Liu <songliubraving@fb.com> wrote: > >>>> > >>>> > >>>> > >>>>> On Aug 2, 2020, at 6:40 PM, Andrii Nakryiko <andrii.nakryiko@gmail.com> wrote: > >>>>> > >>>>> On Sat, Aug 1, 2020 at 1:50 AM Song Liu <songliubraving@fb.com> wrote: > >>>>>> > >>>> > >>>> [...] > >>>> > >>>>> > >>>>>> }; > >>>>>> > >>>>>> LIBBPF_API int bpf_prog_test_run_xattr(struct bpf_prog_test_run_attr *test_attr); > >>>>>> diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c > >>>>>> index b9f11f854985b..9ce175a486214 100644 > >>>>>> --- a/tools/lib/bpf/libbpf.c > >>>>>> +++ b/tools/lib/bpf/libbpf.c > >>>>>> @@ -6922,6 +6922,7 @@ static const struct bpf_sec_def section_defs[] = { > >>>>>> BPF_PROG_SEC("lwt_out", BPF_PROG_TYPE_LWT_OUT), > >>>>>> BPF_PROG_SEC("lwt_xmit", BPF_PROG_TYPE_LWT_XMIT), > >>>>>> BPF_PROG_SEC("lwt_seg6local", BPF_PROG_TYPE_LWT_SEG6LOCAL), > >>>>>> + BPF_PROG_SEC("user", BPF_PROG_TYPE_USER), > >>>>> > >>>>> let's do "user/" for consistency with most other prog types (and nice > >>>>> separation between prog type and custom user name) > >>>> > >>>> About "user" vs. "user/", I still think "user" is better. > >>>> > >>>> Unlike kprobe and tracepoint, user prog doesn't use the part after "/". > >>>> This is similar to "perf_event" for BPF_PROG_TYPE_PERF_EVENT, "xdl" for > >>>> BPF_PROG_TYPE_XDP, etc. If we specify "user" here, "user/" and "user/xxx" > >>>> would also work. However, if we specify "user/" here, programs that used > >>>> "user" by accident will fail to load, with a message like: > >>>> > >>>> libbpf: failed to load program 'user' > >>>> > >>>> which is confusing. > >>> > >>> xdp, perf_event and a bunch of others don't enforce it, that's true, > >>> they are a bit of a legacy, > >> > >> I don't see w/o "/" is a legacy thing. BPF_PROG_TYPE_STRUCT_OPS just uses > >> "struct_ops". > >> > >>> unfortunately. But all the recent ones do, > >>> and we explicitly did that for xdp_dev/xdp_cpu, for instance. > >>> Specifying just "user" in the spec would allow something nonsensical > >>> like "userargh", for instance, due to this being treated as a prefix. > >>> There is no harm to require users to do "user/my_prog", though. > >> > >> I don't see why allowing "userargh" is a problem. Failing "user" is > >> more confusing. We can probably improve that by a hint like: > >> > >> libbpf: failed to load program 'user', do you mean "user/"? > >> > >> But it is pretty silly. "user/something_never_used" also looks weird. > > > > "userargh" is terrible, IMO. It's a different identifier that just > > happens to have the first 4 letters matching "user" program type. > > There must be either a standardized separator (which happens to be > > '/') or none. See the suggestion below. > > We have no problem deal with "a different identifier that just happens > to have the first letters matching", like xdp vs. xdp_devmap and > xdp_cpumap, right? > xdp vs xdp_devmap is an entirely different thing. We deal with it by checking xdp_devmap first. What I'm saying is that user can do "xdpomg" and libbpf would be happy (today). And I don't think that's good. But further, if someone does something like "xdp_devmap_omg", guess which program type will be inferred? Hint: not xdp_devmap and libbpf won't report an error either. All because "xdp" is so lax today. > >> > >>> Alternatively, we could introduce a new convention in the spec, > >>> something like "user?", which would accept either "user" or > >>> "user/something", but not "user/" nor "userblah". We can try that as > >>> well. > >> > >> Again, I don't really understand why allowing "userblah" is a problem. > >> We already have "xdp", "xdp_devmap/", and "xdp_cpumap/", they all work > >> fine so far. > > > > Right, we have "xdp_devmap/" and "xdp_cpumap/", as you say. I haven't > > seen so much pushback against trailing forward slash with those ;) > > I haven't seen any issue with old "perf_event", "xdp" and new "struct_ops" > either. > > > > > But anyways, as part of deprecating APIs and preparing libbpf for 1.0 > > release over this half, I think I'm going to emit warnings for names > > like "prog_type_whatever" or "prog_typeevenworse", etc. And asking > > users to normalize section names to either "prog_type" or > > "prog_type/something/here", whichever makes sense for a specific > > program type. > > Exactly, "user" makes sense here; while "kprobe/__set_task_comm" makes > sense for kprobe. Right, but "userblah" doesn't. It would be great if you could help make what I described above become true. But at least don't make it worse by allowing unrestricted "user" prefix. I'm OK with strict "user" or "user/blah", I'm not OK with "userblah", I'm sorry. > > > Right now libbpf doesn't allow two separate BPF programs > > with the same section name, so enforcing strict "user" is limiting to > > users. We are going to lift that restriction pretty soon, though. But > > for now, please stick with what we've been doing lately and mark it as > > "user/", later we'll allow just "user" as well. > > Since we would allow "user" later, why we have to reject it for now? Because libbpf is dumb in that regard today? And instead of migrating users later, I want to prevent users making bad choices right now. Then relax it, if necessary. Alternatively, we can fix up libbpf logic before the USER program type lands. > Imagine the user just compiled and booted into a new kernel with user > program support; and then got the following message: > > libbpf: failed to load program 'user' > > If I were the user, I would definitely question whether the kernel was > correct... That's also bad, and again, we can make libbpf better. I think moving forward any non-recognized BPF program type should be reported by libbpf as an error. But we can't do it right now, we have to have a period in which users will get a chance to update their BPF programs. This will have to happen over few libbpf releases at least. So please join in on the fun of fixing stuff like this.
> On Aug 4, 2020, at 11:54 PM, Andrii Nakryiko <andrii.nakryiko@gmail.com> wrote: > > On Tue, Aug 4, 2020 at 11:26 PM Song Liu <songliubraving@fb.com> wrote: >> >> >> >>> On Aug 4, 2020, at 10:32 PM, Andrii Nakryiko <andrii.nakryiko@gmail.com> wrote: >>> >>> On Tue, Aug 4, 2020 at 8:59 PM Song Liu <songliubraving@fb.com> wrote: >>>> >>>> >>>> >>>>> On Aug 4, 2020, at 6:38 PM, Andrii Nakryiko <andrii.nakryiko@gmail.com> wrote: >>>>> >>>>> On Mon, Aug 3, 2020 at 6:18 PM Song Liu <songliubraving@fb.com> wrote: >>>>>> >>>>>> >>>>>> >>>>>>> On Aug 2, 2020, at 6:40 PM, Andrii Nakryiko <andrii.nakryiko@gmail.com> wrote: >>>>>>> >>>>>>> On Sat, Aug 1, 2020 at 1:50 AM Song Liu <songliubraving@fb.com> wrote: >>>>>>>> >>>>>> >>>>>> [...] >>>>>> >>>>>>> >>>>>>>> }; >>>>>>>> >>>>>>>> LIBBPF_API int bpf_prog_test_run_xattr(struct bpf_prog_test_run_attr *test_attr); >>>>>>>> diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c >>>>>>>> index b9f11f854985b..9ce175a486214 100644 >>>>>>>> --- a/tools/lib/bpf/libbpf.c >>>>>>>> +++ b/tools/lib/bpf/libbpf.c >>>>>>>> @@ -6922,6 +6922,7 @@ static const struct bpf_sec_def section_defs[] = { >>>>>>>> BPF_PROG_SEC("lwt_out", BPF_PROG_TYPE_LWT_OUT), >>>>>>>> BPF_PROG_SEC("lwt_xmit", BPF_PROG_TYPE_LWT_XMIT), >>>>>>>> BPF_PROG_SEC("lwt_seg6local", BPF_PROG_TYPE_LWT_SEG6LOCAL), >>>>>>>> + BPF_PROG_SEC("user", BPF_PROG_TYPE_USER), >>>>>>> >>>>>>> let's do "user/" for consistency with most other prog types (and nice >>>>>>> separation between prog type and custom user name) >>>>>> >>>>>> About "user" vs. "user/", I still think "user" is better. >>>>>> >>>>>> Unlike kprobe and tracepoint, user prog doesn't use the part after "/". >>>>>> This is similar to "perf_event" for BPF_PROG_TYPE_PERF_EVENT, "xdl" for >>>>>> BPF_PROG_TYPE_XDP, etc. If we specify "user" here, "user/" and "user/xxx" >>>>>> would also work. However, if we specify "user/" here, programs that used >>>>>> "user" by accident will fail to load, with a message like: >>>>>> >>>>>> libbpf: failed to load program 'user' >>>>>> >>>>>> which is confusing. >>>>> >>>>> xdp, perf_event and a bunch of others don't enforce it, that's true, >>>>> they are a bit of a legacy, >>>> >>>> I don't see w/o "/" is a legacy thing. BPF_PROG_TYPE_STRUCT_OPS just uses >>>> "struct_ops". >>>> >>>>> unfortunately. But all the recent ones do, >>>>> and we explicitly did that for xdp_dev/xdp_cpu, for instance. >>>>> Specifying just "user" in the spec would allow something nonsensical >>>>> like "userargh", for instance, due to this being treated as a prefix. >>>>> There is no harm to require users to do "user/my_prog", though. >>>> >>>> I don't see why allowing "userargh" is a problem. Failing "user" is >>>> more confusing. We can probably improve that by a hint like: >>>> >>>> libbpf: failed to load program 'user', do you mean "user/"? >>>> >>>> But it is pretty silly. "user/something_never_used" also looks weird. >>> >>> "userargh" is terrible, IMO. It's a different identifier that just >>> happens to have the first 4 letters matching "user" program type. >>> There must be either a standardized separator (which happens to be >>> '/') or none. See the suggestion below. >> >> We have no problem deal with "a different identifier that just happens >> to have the first letters matching", like xdp vs. xdp_devmap and >> xdp_cpumap, right? >> > > xdp vs xdp_devmap is an entirely different thing. We deal with it by > checking xdp_devmap first. What I'm saying is that user can do > "xdpomg" and libbpf would be happy (today). And I don't think that's > good. But further, if someone does something like "xdp_devmap_omg", > guess which program type will be inferred? Hint: not xdp_devmap and > libbpf won't report an error either. All because "xdp" is so lax > today. > >>>> >>>>> Alternatively, we could introduce a new convention in the spec, >>>>> something like "user?", which would accept either "user" or >>>>> "user/something", but not "user/" nor "userblah". We can try that as >>>>> well. >>>> >>>> Again, I don't really understand why allowing "userblah" is a problem. >>>> We already have "xdp", "xdp_devmap/", and "xdp_cpumap/", they all work >>>> fine so far. >>> >>> Right, we have "xdp_devmap/" and "xdp_cpumap/", as you say. I haven't >>> seen so much pushback against trailing forward slash with those ;) >> >> I haven't seen any issue with old "perf_event", "xdp" and new "struct_ops" >> either. >> >>> >>> But anyways, as part of deprecating APIs and preparing libbpf for 1.0 >>> release over this half, I think I'm going to emit warnings for names >>> like "prog_type_whatever" or "prog_typeevenworse", etc. And asking >>> users to normalize section names to either "prog_type" or >>> "prog_type/something/here", whichever makes sense for a specific >>> program type. >> >> Exactly, "user" makes sense here; while "kprobe/__set_task_comm" makes >> sense for kprobe. > > Right, but "userblah" doesn't. It would be great if you could help > make what I described above become true. But at least don't make it > worse by allowing unrestricted "user" prefix. I'm OK with strict > "user" or "user/blah", I'm not OK with "userblah", I'm sorry. If the concern with "userblah" is real and unbearable, so is "xdpblah" and "perf_eventblah", and so on, and so on. > >> >>> Right now libbpf doesn't allow two separate BPF programs >>> with the same section name, so enforcing strict "user" is limiting to >>> users. We are going to lift that restriction pretty soon, though. But >>> for now, please stick with what we've been doing lately and mark it as >>> "user/", later we'll allow just "user" as well. >> >> Since we would allow "user" later, why we have to reject it for now? > > Because libbpf is dumb in that regard today? And instead of migrating > users later, I want to prevent users making bad choices right now. The good choice here is to use "user", IMO. And you are preventing people to use it. If user has to use "user/" for now. They will have to update the programs later, right? If the conclusion is "user/xxx" is the ultimate goal, I would agree with "user/" for now. > Then relax it, if necessary. Alternatively, we can fix up libbpf logic > before the USER program type lands. I don't see why the USER program type need to wait for libbpf fix, as "xdp", "perf_event", etc. all work well today. > >> Imagine the user just compiled and booted into a new kernel with user >> program support; and then got the following message: >> >> libbpf: failed to load program 'user' >> >> If I were the user, I would definitely question whether the kernel was >> correct... > > That's also bad, and again, we can make libbpf better. I think moving > forward any non-recognized BPF program type should be reported by > libbpf as an error. But we can't do it right now, we have to have a > period in which users will get a chance to update their BPF programs. > This will have to happen over few libbpf releases at least. So please > join in on the fun of fixing stuff like this. I'd love to join the fun. Maybe after user program lands ;)
On Wed, Aug 5, 2020 at 12:23 AM Song Liu <songliubraving@fb.com> wrote: > > > > > On Aug 4, 2020, at 11:54 PM, Andrii Nakryiko <andrii.nakryiko@gmail.com> wrote: > > > > On Tue, Aug 4, 2020 at 11:26 PM Song Liu <songliubraving@fb.com> wrote: > >> > >> > >> > >>> On Aug 4, 2020, at 10:32 PM, Andrii Nakryiko <andrii.nakryiko@gmail.com> wrote: > >>> > >>> On Tue, Aug 4, 2020 at 8:59 PM Song Liu <songliubraving@fb.com> wrote: > >>>> > >>>> > >>>> > >>>>> On Aug 4, 2020, at 6:38 PM, Andrii Nakryiko <andrii.nakryiko@gmail.com> wrote: > >>>>> > >>>>> On Mon, Aug 3, 2020 at 6:18 PM Song Liu <songliubraving@fb.com> wrote: > >>>>>> > >>>>>> > >>>>>> > >>>>>>> On Aug 2, 2020, at 6:40 PM, Andrii Nakryiko <andrii.nakryiko@gmail.com> wrote: > >>>>>>> > >>>>>>> On Sat, Aug 1, 2020 at 1:50 AM Song Liu <songliubraving@fb.com> wrote: > >>>>>>>> > >>>>>> > >>>>>> [...] > >>>>>> > >>>>>>> > >>>>>>>> }; > >>>>>>>> > >>>>>>>> LIBBPF_API int bpf_prog_test_run_xattr(struct bpf_prog_test_run_attr *test_attr); > >>>>>>>> diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c > >>>>>>>> index b9f11f854985b..9ce175a486214 100644 > >>>>>>>> --- a/tools/lib/bpf/libbpf.c > >>>>>>>> +++ b/tools/lib/bpf/libbpf.c > >>>>>>>> @@ -6922,6 +6922,7 @@ static const struct bpf_sec_def section_defs[] = { > >>>>>>>> BPF_PROG_SEC("lwt_out", BPF_PROG_TYPE_LWT_OUT), > >>>>>>>> BPF_PROG_SEC("lwt_xmit", BPF_PROG_TYPE_LWT_XMIT), > >>>>>>>> BPF_PROG_SEC("lwt_seg6local", BPF_PROG_TYPE_LWT_SEG6LOCAL), > >>>>>>>> + BPF_PROG_SEC("user", BPF_PROG_TYPE_USER), > >>>>>>> > >>>>>>> let's do "user/" for consistency with most other prog types (and nice > >>>>>>> separation between prog type and custom user name) > >>>>>> > >>>>>> About "user" vs. "user/", I still think "user" is better. > >>>>>> > >>>>>> Unlike kprobe and tracepoint, user prog doesn't use the part after "/". > >>>>>> This is similar to "perf_event" for BPF_PROG_TYPE_PERF_EVENT, "xdl" for > >>>>>> BPF_PROG_TYPE_XDP, etc. If we specify "user" here, "user/" and "user/xxx" > >>>>>> would also work. However, if we specify "user/" here, programs that used > >>>>>> "user" by accident will fail to load, with a message like: > >>>>>> > >>>>>> libbpf: failed to load program 'user' > >>>>>> > >>>>>> which is confusing. > >>>>> > >>>>> xdp, perf_event and a bunch of others don't enforce it, that's true, > >>>>> they are a bit of a legacy, > >>>> > >>>> I don't see w/o "/" is a legacy thing. BPF_PROG_TYPE_STRUCT_OPS just uses > >>>> "struct_ops". > >>>> > >>>>> unfortunately. But all the recent ones do, > >>>>> and we explicitly did that for xdp_dev/xdp_cpu, for instance. > >>>>> Specifying just "user" in the spec would allow something nonsensical > >>>>> like "userargh", for instance, due to this being treated as a prefix. > >>>>> There is no harm to require users to do "user/my_prog", though. > >>>> > >>>> I don't see why allowing "userargh" is a problem. Failing "user" is > >>>> more confusing. We can probably improve that by a hint like: > >>>> > >>>> libbpf: failed to load program 'user', do you mean "user/"? > >>>> > >>>> But it is pretty silly. "user/something_never_used" also looks weird. > >>> > >>> "userargh" is terrible, IMO. It's a different identifier that just > >>> happens to have the first 4 letters matching "user" program type. > >>> There must be either a standardized separator (which happens to be > >>> '/') or none. See the suggestion below. > >> > >> We have no problem deal with "a different identifier that just happens > >> to have the first letters matching", like xdp vs. xdp_devmap and > >> xdp_cpumap, right? > >> > > > > xdp vs xdp_devmap is an entirely different thing. We deal with it by > > checking xdp_devmap first. What I'm saying is that user can do > > "xdpomg" and libbpf would be happy (today). And I don't think that's > > good. But further, if someone does something like "xdp_devmap_omg", > > guess which program type will be inferred? Hint: not xdp_devmap and > > libbpf won't report an error either. All because "xdp" is so lax > > today. > > > >>>> > >>>>> Alternatively, we could introduce a new convention in the spec, > >>>>> something like "user?", which would accept either "user" or > >>>>> "user/something", but not "user/" nor "userblah". We can try that as > >>>>> well. > >>>> > >>>> Again, I don't really understand why allowing "userblah" is a problem. > >>>> We already have "xdp", "xdp_devmap/", and "xdp_cpumap/", they all work > >>>> fine so far. > >>> > >>> Right, we have "xdp_devmap/" and "xdp_cpumap/", as you say. I haven't > >>> seen so much pushback against trailing forward slash with those ;) > >> > >> I haven't seen any issue with old "perf_event", "xdp" and new "struct_ops" > >> either. > >> > >>> > >>> But anyways, as part of deprecating APIs and preparing libbpf for 1.0 > >>> release over this half, I think I'm going to emit warnings for names > >>> like "prog_type_whatever" or "prog_typeevenworse", etc. And asking > >>> users to normalize section names to either "prog_type" or > >>> "prog_type/something/here", whichever makes sense for a specific > >>> program type. > >> > >> Exactly, "user" makes sense here; while "kprobe/__set_task_comm" makes > >> sense for kprobe. > > > > Right, but "userblah" doesn't. It would be great if you could help > > make what I described above become true. But at least don't make it > > worse by allowing unrestricted "user" prefix. I'm OK with strict > > "user" or "user/blah", I'm not OK with "userblah", I'm sorry. > > If the concern with "userblah" is real and unbearable, so is "xdpblah" > and "perf_eventblah", and so on, and so on. > Oh yeah, "xdpblah" makes me cringe. "Some other kid is doing wrong thing, let me do it as well" style of argument never worked for me with my parents, I don't see why it should work here :) But anyways, let's table this discussion, it's not worth spending so much time on it. As I said, I'm going to start enforcing standardized separator or a single program type word soon enough. Might as well do that for "userblah". > > > >> > >>> Right now libbpf doesn't allow two separate BPF programs > >>> with the same section name, so enforcing strict "user" is limiting to > >>> users. We are going to lift that restriction pretty soon, though. But > >>> for now, please stick with what we've been doing lately and mark it as > >>> "user/", later we'll allow just "user" as well. > >> > >> Since we would allow "user" later, why we have to reject it for now? > > > > Because libbpf is dumb in that regard today? And instead of migrating > > users later, I want to prevent users making bad choices right now. > > The good choice here is to use "user", IMO. And you are preventing people > to use it. If user has to use "user/" for now. They will have to update > the programs later, right? If the conclusion is "user/xxx" is the ultimate > goal, I would agree with "user/" for now. They won't have to update, "user/something" would still work. > > > Then relax it, if necessary. Alternatively, we can fix up libbpf logic > > before the USER program type lands. > > I don't see why the USER program type need to wait for libbpf fix, as > "xdp", "perf_event", etc. all work well today. It's about being a good citizen and helping move libbpf forward. > > > > >> Imagine the user just compiled and booted into a new kernel with user > >> program support; and then got the following message: > >> > >> libbpf: failed to load program 'user' > >> > >> If I were the user, I would definitely question whether the kernel was > >> correct... > > > > That's also bad, and again, we can make libbpf better. I think moving > > forward any non-recognized BPF program type should be reported by > > libbpf as an error. But we can't do it right now, we have to have a > > period in which users will get a chance to update their BPF programs. > > This will have to happen over few libbpf releases at least. So please > > join in on the fun of fixing stuff like this. > > I'd love to join the fun. Maybe after user program lands ;) > > Of course :) see above.
diff --git a/tools/lib/bpf/bpf.c b/tools/lib/bpf/bpf.c index e1bdf214f75fe..b28c3daa9c270 100644 --- a/tools/lib/bpf/bpf.c +++ b/tools/lib/bpf/bpf.c @@ -693,6 +693,7 @@ int bpf_prog_test_run_xattr(struct bpf_prog_test_run_attr *test_attr) attr.test.ctx_size_in = test_attr->ctx_size_in; attr.test.ctx_size_out = test_attr->ctx_size_out; attr.test.repeat = test_attr->repeat; + attr.test.cpu_plus = test_attr->cpu_plus; ret = sys_bpf(BPF_PROG_TEST_RUN, &attr, sizeof(attr)); test_attr->data_size_out = attr.test.data_size_out; diff --git a/tools/lib/bpf/bpf.h b/tools/lib/bpf/bpf.h index 6d367e01d05e9..0c799740df566 100644 --- a/tools/lib/bpf/bpf.h +++ b/tools/lib/bpf/bpf.h @@ -205,6 +205,9 @@ struct bpf_prog_test_run_attr { void *ctx_out; /* optional */ __u32 ctx_size_out; /* in: max length of ctx_out * out: length of cxt_out */ + __u32 cpu_plus; /* specify which cpu to run the test with + * cpu_plus = cpu_id + 1. + * If cpu_plus = 0, run on current cpu */ }; LIBBPF_API int bpf_prog_test_run_xattr(struct bpf_prog_test_run_attr *test_attr); diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c index b9f11f854985b..9ce175a486214 100644 --- a/tools/lib/bpf/libbpf.c +++ b/tools/lib/bpf/libbpf.c @@ -6922,6 +6922,7 @@ static const struct bpf_sec_def section_defs[] = { BPF_PROG_SEC("lwt_out", BPF_PROG_TYPE_LWT_OUT), BPF_PROG_SEC("lwt_xmit", BPF_PROG_TYPE_LWT_XMIT), BPF_PROG_SEC("lwt_seg6local", BPF_PROG_TYPE_LWT_SEG6LOCAL), + BPF_PROG_SEC("user", BPF_PROG_TYPE_USER), BPF_APROG_SEC("cgroup_skb/ingress", BPF_PROG_TYPE_CGROUP_SKB, BPF_CGROUP_INET_INGRESS), BPF_APROG_SEC("cgroup_skb/egress", BPF_PROG_TYPE_CGROUP_SKB, diff --git a/tools/lib/bpf/libbpf_probes.c b/tools/lib/bpf/libbpf_probes.c index 5a3d3f0784081..163013084000e 100644 --- a/tools/lib/bpf/libbpf_probes.c +++ b/tools/lib/bpf/libbpf_probes.c @@ -112,6 +112,7 @@ probe_load(enum bpf_prog_type prog_type, const struct bpf_insn *insns, case BPF_PROG_TYPE_STRUCT_OPS: case BPF_PROG_TYPE_EXT: case BPF_PROG_TYPE_LSM: + case BPF_PROG_TYPE_USER: default: break; }
Add cpu_plus to bpf_prog_test_run_attr. Add BPF_PROG_SEC "user" for BPF_PROG_TYPE_USER programs. Signed-off-by: Song Liu <songliubraving@fb.com> --- tools/lib/bpf/bpf.c | 1 + tools/lib/bpf/bpf.h | 3 +++ tools/lib/bpf/libbpf.c | 1 + tools/lib/bpf/libbpf_probes.c | 1 + 4 files changed, 6 insertions(+)