@@ -24,9 +24,11 @@ FEATURE COMMANDS
================
| **bpftool** **feature probe** [*COMPONENT*] [**full**] [**unprivileged**] [**macros** [**prefix** *PREFIX*]]
+| **bpftool** **feature list** *GROUP*
| **bpftool** **feature help**
|
| *COMPONENT* := { **kernel** | **dev** *NAME* }
+| *GROUP* := { **prog_types** | **map_types** | **attach_types** | **link_types** | **helpers** }
DESCRIPTION
===========
@@ -70,6 +72,16 @@ DESCRIPTION
The keywords **full**, **macros** and **prefix** have the
same role as when probing the kernel.
+ **bpftool feature list** *GROUP*
+ List items known to bpftool. These can be BPF program types
+ (**prog_types**), BPF map types (**map_types**), attach types
+ (**attach_types**), link types (**link_types**), or BPF helper
+ functions (**helpers**). The command does not probe the system, but
+ simply lists the elements that bpftool knows from compilation time,
+ as provided from libbpf (for all object types) or from the BPF UAPI
+ header (list of helpers). This can be used in scripts to iterate over
+ BPF types or helpers.
+
**bpftool feature help**
Print short help message.
@@ -1175,9 +1175,14 @@ _bpftool()
_bpftool_once_attr 'full unprivileged'
return 0
;;
+ list)
+ [[ $prev != "$command" ]] && return 0
+ COMPREPLY=( $( compgen -W 'prog_types map_types \
+ attach_types link_types helpers' -- "$cur" ) )
+ ;;
*)
[[ $prev == $object ]] && \
- COMPREPLY=( $( compgen -W 'help probe' -- "$cur" ) )
+ COMPREPLY=( $( compgen -W 'help list probe' -- "$cur" ) )
;;
esac
;;
@@ -1258,6 +1258,58 @@ static int do_probe(int argc, char **argv)
return 0;
}
+static const char *get_helper_name(unsigned int id)
+{
+ if (id >= ARRAY_SIZE(helper_name))
+ return NULL;
+
+ return helper_name[id];
+}
+
+static int do_list(int argc, char **argv)
+{
+ const char *(*get_name)(unsigned int id);
+ unsigned int id = 0;
+
+ if (argc < 1)
+ usage();
+
+ if (is_prefix(*argv, "prog_types")) {
+ get_name = (const char *(*)(unsigned int))libbpf_bpf_prog_type_str;
+ } else if (is_prefix(*argv, "map_types")) {
+ get_name = (const char *(*)(unsigned int))libbpf_bpf_map_type_str;
+ } else if (is_prefix(*argv, "attach_types")) {
+ get_name = (const char *(*)(unsigned int))libbpf_bpf_attach_type_str;
+ } else if (is_prefix(*argv, "link_types")) {
+ get_name = (const char *(*)(unsigned int))libbpf_bpf_link_type_str;
+ } else if (is_prefix(*argv, "helpers")) {
+ get_name = get_helper_name;
+ } else {
+ p_err("expected 'prog_types', 'map_types', 'attach_types', 'link_types' or 'helpers', got: %s", *argv);
+ return -1;
+ }
+
+ if (json_output)
+ jsonw_start_array(json_wtr); /* root array */
+
+ while (true) {
+ const char *name;
+
+ name = get_name(id++);
+ if (!name)
+ break;
+ if (json_output)
+ jsonw_string(json_wtr, name);
+ else
+ printf("%s\n", name);
+ }
+
+ if (json_output)
+ jsonw_end_array(json_wtr); /* root array */
+
+ return 0;
+}
+
static int do_help(int argc, char **argv)
{
if (json_output) {
@@ -1267,9 +1319,11 @@ static int do_help(int argc, char **argv)
fprintf(stderr,
"Usage: %1$s %2$s probe [COMPONENT] [full] [unprivileged] [macros [prefix PREFIX]]\n"
+ " %1$s %2$s list GROUP\n"
" %1$s %2$s help\n"
"\n"
" COMPONENT := { kernel | dev NAME }\n"
+ " GROUP := { prog_types | map_types | attach_types | link_types | helpers }\n"
" " HELP_SPEC_OPTIONS " }\n"
"",
bin_name, argv[-2]);
@@ -1279,6 +1333,7 @@ static int do_help(int argc, char **argv)
static const struct cmd cmds[] = {
{ "probe", do_probe },
+ { "list", do_list },
{ "help", do_help },
{ 0 }
};
Add a "bpftool feature list" subcommand to list BPF "features". Contrarily to "bpftool feature probe", this is not about the features available on the system. Instead, it lists all features known to bpftool from compilation time; in other words, all program, map, attach, link types known to the libbpf version in use, and all helpers found in the UAPI BPF header. The first use case for this feature is bash completion: running the command provides a list of types that can be used to produce the list of candidate map types, for example. Now that bpftool uses "standard" names provided by libbpf for the program, map, link, and attach types, having the ability to list these types and helpers could also be useful in scripts to loop over existing items. Sample output: # bpftool feature list prog_types | grep -vw unspec | head -n 6 socket_filter kprobe sched_cls sched_act tracepoint xdp # bpftool -p feature list map_types | jq '.[1]' "hash" # bpftool feature list attach_types | grep '^cgroup_' cgroup_inet_ingress cgroup_inet_egress [...] cgroup_inet_sock_release # bpftool feature list helpers | grep -vw bpf_unspec | wc -l 207 The "unspec" types and helpers are not filtered out by bpftool, so as to remain closer to the enums, and to preserve the indices in the JSON arrays (e.g. "hash" at index 1 == BPF_MAP_TYPE_HASH in map types list). v2: Add missing "link_types" to the list of GROUPs in man page. Acked-by: Daniel Müller <deso@posteo.net> Signed-off-by: Quentin Monnet <quentin@isovalent.com> --- .../bpftool/Documentation/bpftool-feature.rst | 12 ++++ tools/bpf/bpftool/bash-completion/bpftool | 7 ++- tools/bpf/bpftool/feature.c | 55 +++++++++++++++++++ 3 files changed, 73 insertions(+), 1 deletion(-)