On 2023-05-12 15:36:47 +0200, Larysa Zaremba wrote: > [You don't often get email from larysa.zaremba@xxxxxxxxx. Learn why this is important at https://aka.ms/LearnAboutSenderIdentification ] > > On Fri, May 12, 2023 at 11:23:00AM +0100, Quentin Monnet wrote: > > 2023-05-11 17:13 UTC+0200 ~ Larysa Zaremba <larysa.zaremba@xxxxxxxxx> > > > Add ability to specify a network interface used to resolve > > > XDP Hints kfuncs when loading program through bpftool. > > > > > > Usage: > > > bpftool prog load <bpf_obj_path> <pin_path> dev xdpmeta <ifname> > > > > Thanks for this patch! > > > > Regarding the command-line syntax, I'm not a big fan of the optional > > sub-keyword for the device for XDP hints. I must admit I had not > > anticipated other another use for the "dev" keyword. Instead, have you > > considered one of the following: > > > > 1) Adding a different keyword ("xdpmeta_dev"?) and making it > > incompatible with "dev" > > > > 2) Another alternative would be adding a sub-keyword for offload too: > > > > bpftool p l [...] dev <[offload <ifname> | xdpmeta <ifname>]> > > > > If the ifname is provided with no sub-keyword, we would consider it for > > offload for legacy support, possibly warn that the syntax is deprecated. > > > > What do you think? > > > > I think first option would look a little bit nicer, but I like the idea to > deprecate "dev <ifname>". In my current version, forgetting to add "xdpmeta" > resulted in not very descriptive errors, this may confuse new users. So what > about: I agree the first option looks a little bit nicer, but I think both options would work. > > bpftool prog load [...] xdpmeta_dev/offload_dev <ifname> > > "dev <ifname>" syntax would still work, but with a big warning, like this: > > 'bpftool prog [...] dev <ifname>' syntax is deprecated. Going further, please > use 'offload_dev <ifname>' to offload program to device. For XDP hints > applications, use 'xdpmeta_dev <ifname>'. > > > > > > > Signed-off-by: Larysa Zaremba <larysa.zaremba@xxxxxxxxx> > > > --- > > > tools/bpf/bpftool/prog.c | 28 +++++++++++++++++++++------- > > > 1 file changed, 21 insertions(+), 7 deletions(-) > > > > > > diff --git a/tools/bpf/bpftool/prog.c b/tools/bpf/bpftool/prog.c > > > index 91b6075b2db3..a9cb96d99277 100644 > > > --- a/tools/bpf/bpftool/prog.c > > > +++ b/tools/bpf/bpftool/prog.c > > > @@ -1517,12 +1517,13 @@ static int load_with_options(int argc, char **argv, bool first_prog_only) > > > struct bpf_program *prog = NULL, *pos; > > > unsigned int old_map_fds = 0; > > > const char *pinmaps = NULL; > > > + __u32 offload_ifindex = 0; > > > bool auto_attach = false; > > > + __u32 meta_ifindex = 0; > > > struct bpf_object *obj; > > > struct bpf_map *map; > > > const char *pinfile; > > > unsigned int i, j; > > > - __u32 ifindex = 0; > > > const char *file; > > > int idx, err; > > > > > > @@ -1614,17 +1615,25 @@ static int load_with_options(int argc, char **argv, bool first_prog_only) > > > map_replace[old_map_fds].fd = fd; > > > old_map_fds++; > > > } else if (is_prefix(*argv, "dev")) { > > > + __u32 *cur_ifindex; > > > + > > > NEXT_ARG(); > > > > > > - if (ifindex) { > > > - p_err("offload device already specified"); > > > + if (offload_ifindex || meta_ifindex) { > > > + p_err("device already specified"); > > > > I'd add a note to tell somehow that offload and XDP hints are mutually > > exclusive. I suspect not all users understand these well. > > Ok, will do. > > > > > > goto err_free_reuse_maps; > > > } > > > + if (is_prefix(*argv, "xdpmeta")) { > > > + cur_ifindex = &meta_ifindex; > > > + NEXT_ARG(); > > > + } else { > > > + cur_ifindex = &offload_ifindex; > > > + } > > > if (!REQ_ARGS(1)) > > > goto err_free_reuse_maps; > > > > > > - ifindex = if_nametoindex(*argv); > > > - if (!ifindex) { > > > + *cur_ifindex = if_nametoindex(*argv); > > > + if (!(*cur_ifindex)) { > > > p_err("unrecognized netdevice '%s': %s", > > > *argv, strerror(errno)); > > > goto err_free_reuse_maps; > > > @@ -1671,7 +1680,12 @@ static int load_with_options(int argc, char **argv, bool first_prog_only) > > > goto err_close_obj; > > > } > > > > > > - bpf_program__set_ifindex(pos, ifindex); > > > + if (prog_type == BPF_PROG_TYPE_XDP && meta_ifindex) { > > > + bpf_program__set_flags(pos, BPF_F_XDP_DEV_BOUND_ONLY); > > > + bpf_program__set_ifindex(pos, meta_ifindex); > > > + } else { > > > + bpf_program__set_ifindex(pos, offload_ifindex); > > > + } > > > if (bpf_program__type(pos) != prog_type) > > > bpf_program__set_type(pos, prog_type); > > > bpf_program__set_expected_attach_type(pos, expected_attach_type); > > > @@ -1709,7 +1723,7 @@ static int load_with_options(int argc, char **argv, bool first_prog_only) > > > idx = 0; > > > bpf_object__for_each_map(map, obj) { > > > if (bpf_map__type(map) != BPF_MAP_TYPE_PERF_EVENT_ARRAY) > > > - bpf_map__set_ifindex(map, ifindex); > > > + bpf_map__set_ifindex(map, offload_ifindex); > > > > > > if (j < old_map_fds && idx == map_replace[j].idx) { > > > err = bpf_map__reuse_fd(map, map_replace[j++].fd); > > > > Could you please also update the following items: > > > > - The usage message for "bpftool prog load" near the end of prog.c > > > > - The related doc in Documentation/bpftool-prog.rst (command summary > > near the top, and detailed description later in the doc) > > > > - Bash completion (for keyword "dev", look for "_sysfs_get_netdevs" in > > bash-completion/bpftool). I'm happy to help with this one if necessary. > > Will do all the above in v2. > > > > > Thanks, > > Quentin -- Kind Regards, Niklas Söderlund
