diff options
-rw-r--r-- | tools/bpf/bpftool/Documentation/bpftool-feature.rst | 18 | ||||
-rw-r--r-- | tools/bpf/bpftool/feature.c | 69 |
2 files changed, 73 insertions, 14 deletions
diff --git a/tools/bpf/bpftool/Documentation/bpftool-feature.rst b/tools/bpf/bpftool/Documentation/bpftool-feature.rst index 53092995f46b..8d489a26e3c9 100644 --- a/tools/bpf/bpftool/Documentation/bpftool-feature.rst +++ b/tools/bpf/bpftool/Documentation/bpftool-feature.rst @@ -19,14 +19,18 @@ SYNOPSIS MAP COMMANDS ============= -| **bpftool** **feature probe** [**kernel**] [**macros** [**prefix** *PREFIX*]] +| **bpftool** **feature probe** [*COMPONENT*] [**macros** [**prefix** *PREFIX*]] | **bpftool** **feature help** +| +| *COMPONENT* := { **kernel** | **dev** *NAME* } DESCRIPTION =========== **bpftool feature probe** [**kernel**] [**macros** [**prefix** *PREFIX*]] Probe the running kernel and dump a number of eBPF-related - parameters, such as availability of the **bpf()** system call. + parameters, such as availability of the **bpf()** system call, + JIT status, eBPF program types availability, eBPF helper + functions availability, and more. If the **macros** keyword (but not the **-j** option) is passed, a subset of the output is dumped as a list of @@ -37,12 +41,20 @@ DESCRIPTION avoid conflicts on macro names when including the output of this command as a header file. - Keyword **kernel** can be omitted. + Keyword **kernel** can be omitted. If no probe target is + specified, probing the kernel is the default behaviour. Note that when probed, some eBPF helpers (e.g. **bpf_trace_printk**\ () or **bpf_probe_write_user**\ ()) may print warnings to kernel logs. + **bpftool feature probe dev** *NAME* [**macros** [**prefix** *PREFIX*]] + Probe network device for supported eBPF features and dump + results to the console. + + The two keywords **macros** and **prefix** have the same + role as when probing the kernel. + **bpftool feature help** Print short help message. diff --git a/tools/bpf/bpftool/feature.c b/tools/bpf/bpftool/feature.c index a62e637953b7..993c6f1e5473 100644 --- a/tools/bpf/bpftool/feature.c +++ b/tools/bpf/bpftool/feature.c @@ -5,6 +5,7 @@ #include <errno.h> #include <string.h> #include <unistd.h> +#include <net/if.h> #include <sys/utsname.h> #include <sys/vfs.h> @@ -23,6 +24,7 @@ enum probe_component { COMPONENT_UNSPEC, COMPONENT_KERNEL, + COMPONENT_DEVICE, }; #define BPF_HELPER_MAKE_ENTRY(name) [BPF_FUNC_ ## name] = "bpf_" # name @@ -456,14 +458,24 @@ static bool probe_bpf_syscall(const char *define_prefix) static void probe_prog_type(enum bpf_prog_type prog_type, bool *supported_types, - const char *define_prefix) + const char *define_prefix, __u32 ifindex) { char feat_name[128], plain_desc[128], define_name[128]; const char *plain_comment = "eBPF program_type "; size_t maxlen; bool res; - res = bpf_probe_prog_type(prog_type, 0); + if (ifindex) + /* Only test offload-able program types */ + switch (prog_type) { + case BPF_PROG_TYPE_SCHED_CLS: + case BPF_PROG_TYPE_XDP: + break; + default: + return; + } + + res = bpf_probe_prog_type(prog_type, ifindex); supported_types[prog_type] |= res; @@ -482,14 +494,15 @@ probe_prog_type(enum bpf_prog_type prog_type, bool *supported_types, } static void -probe_map_type(enum bpf_map_type map_type, const char *define_prefix) +probe_map_type(enum bpf_map_type map_type, const char *define_prefix, + __u32 ifindex) { char feat_name[128], plain_desc[128], define_name[128]; const char *plain_comment = "eBPF map_type "; size_t maxlen; bool res; - res = bpf_probe_map_type(map_type, 0); + res = bpf_probe_map_type(map_type, ifindex); maxlen = sizeof(plain_desc) - strlen(plain_comment) - 1; if (strlen(map_type_name[map_type]) > maxlen) { @@ -507,13 +520,23 @@ probe_map_type(enum bpf_map_type map_type, const char *define_prefix) static void probe_helpers_for_progtype(enum bpf_prog_type prog_type, bool supported_type, - const char *define_prefix) + const char *define_prefix, __u32 ifindex) { const char *ptype_name = prog_type_name[prog_type]; char feat_name[128]; unsigned int id; bool res; + if (ifindex) + /* Only test helpers for offload-able program types */ + switch (prog_type) { + case BPF_PROG_TYPE_SCHED_CLS: + case BPF_PROG_TYPE_XDP: + break; + default: + return; + } + if (json_output) { sprintf(feat_name, "%s_available_helpers", ptype_name); jsonw_name(json_wtr, feat_name); @@ -527,7 +550,7 @@ probe_helpers_for_progtype(enum bpf_prog_type prog_type, bool supported_type, if (!supported_type) res = false; else - res = bpf_probe_helper(id, prog_type, 0); + res = bpf_probe_helper(id, prog_type, ifindex); if (json_output) { if (res) @@ -553,7 +576,9 @@ static int do_probe(int argc, char **argv) enum probe_component target = COMPONENT_UNSPEC; const char *define_prefix = NULL; bool supported_types[128] = {}; + __u32 ifindex = 0; unsigned int i; + char *ifname; /* Detection assumes user has sufficient privileges (CAP_SYS_ADMIN). * Let's approximate, and restrict usage to root user only. @@ -573,6 +598,24 @@ static int do_probe(int argc, char **argv) } target = COMPONENT_KERNEL; NEXT_ARG(); + } else if (is_prefix(*argv, "dev")) { + NEXT_ARG(); + + if (target != COMPONENT_UNSPEC || ifindex) { + p_err("component to probe already specified"); + return -1; + } + if (!REQ_ARGS(1)) + return -1; + + target = COMPONENT_DEVICE; + ifname = GET_ARG(); + ifindex = if_nametoindex(ifname); + if (!ifindex) { + p_err("unrecognized netdevice '%s': %s", ifname, + strerror(errno)); + return -1; + } } else if (is_prefix(*argv, "macros") && !define_prefix) { define_prefix = ""; NEXT_ARG(); @@ -591,7 +634,7 @@ static int do_probe(int argc, char **argv) return -1; define_prefix = GET_ARG(); } else { - p_err("expected no more arguments, 'kernel', 'macros' or 'prefix', got: '%s'?", + p_err("expected no more arguments, 'kernel', 'dev', 'macros' or 'prefix', got: '%s'?", *argv); return -1; } @@ -627,6 +670,8 @@ static int do_probe(int argc, char **argv) else printf("\n"); break; + default: + break; } print_start_section("syscall_config", @@ -644,7 +689,7 @@ static int do_probe(int argc, char **argv) define_prefix); for (i = BPF_PROG_TYPE_UNSPEC + 1; i < ARRAY_SIZE(prog_type_name); i++) - probe_prog_type(i, supported_types, define_prefix); + probe_prog_type(i, supported_types, define_prefix, ifindex); print_end_then_start_section("map_types", "Scanning eBPF map types...", @@ -652,7 +697,7 @@ static int do_probe(int argc, char **argv) define_prefix); for (i = BPF_MAP_TYPE_UNSPEC + 1; i < map_type_name_size; i++) - probe_map_type(i, define_prefix); + probe_map_type(i, define_prefix, ifindex); print_end_then_start_section("helpers", "Scanning eBPF helper functions...", @@ -676,7 +721,7 @@ static int do_probe(int argc, char **argv) define_prefix); for (i = BPF_PROG_TYPE_UNSPEC + 1; i < ARRAY_SIZE(prog_type_name); i++) probe_helpers_for_progtype(i, supported_types[i], - define_prefix); + define_prefix, ifindex); exit_close_json: if (json_output) { @@ -697,8 +742,10 @@ static int do_help(int argc, char **argv) } fprintf(stderr, - "Usage: %s %s probe [kernel] [macros [prefix PREFIX]]\n" + "Usage: %s %s probe [COMPONENT] [macros [prefix PREFIX]]\n" " %s %s help\n" + "\n" + " COMPONENT := { kernel | dev NAME }\n" "", bin_name, argv[-2], bin_name, argv[-2]); 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