diff options
author | Andrii Nakryiko <andrii@kernel.org> | 2022-05-09 17:16:05 -0700 |
---|---|---|
committer | Andrii Nakryiko <andrii@kernel.org> | 2022-05-09 17:16:05 -0700 |
commit | bfa92e0bdc8ee5d444086fa25489de861a17b085 (patch) | |
tree | fcfdc05cea7c63cb457c771f560047bfa8371197 | |
parent | 7b3a06382442c4d83c9d35253638cb3f561da9b9 (diff) | |
parent | b06a92a18d4651c983c60d83935a76b2d47d85e0 (diff) |
Merge branch 'bpftool: fix feature output when helper probes fail'
Milan Landaverde says:
====================
Currently in bpftool's feature probe, we incorrectly tell the user that
all of the helper functions are supported for program types where helper
probing fails or is explicitly unsupported[1]:
$ bpftool feature probe
...
eBPF helpers supported for program type tracing:
- bpf_map_lookup_elem
- bpf_map_update_elem
- bpf_map_delete_elem
...
- bpf_redirect_neigh
- bpf_check_mtu
- bpf_sys_bpf
- bpf_sys_close
This patch adjusts bpftool to relay to the user when helper support
can't be determined:
$ bpftool feature probe
...
eBPF helpers supported for program type lirc_mode2:
Program type not supported
eBPF helpers supported for program type tracing:
Could not determine which helpers are available
eBPF helpers supported for program type struct_opts:
Could not determine which helpers are available
eBPF helpers supported for program type ext:
Could not determine which helpers are available
Rather than imply that no helpers are available for the program type, we
let the user know that helper function probing failed entirely.
[1] https://lore.kernel.org/bpf/20211217171202.3352835-2-andrii@kernel.org/
====================
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
-rw-r--r-- | tools/bpf/bpftool/feature.c | 22 |
1 files changed, 17 insertions, 5 deletions
diff --git a/tools/bpf/bpftool/feature.c b/tools/bpf/bpftool/feature.c index be130e35462f..d12f46051aac 100644 --- a/tools/bpf/bpftool/feature.c +++ b/tools/bpf/bpftool/feature.c @@ -638,7 +638,7 @@ probe_map_type(enum bpf_map_type map_type, const char *define_prefix, res = probe_map_type_ifindex(map_type, ifindex); } else { - res = libbpf_probe_bpf_map_type(map_type, NULL); + res = libbpf_probe_bpf_map_type(map_type, NULL) > 0; } /* Probe result depends on the success of map creation, no additional @@ -690,7 +690,7 @@ probe_helper_ifindex(enum bpf_func_id id, enum bpf_prog_type prog_type, return res; } -static void +static bool probe_helper_for_progtype(enum bpf_prog_type prog_type, bool supported_type, const char *define_prefix, unsigned int id, const char *ptype_name, __u32 ifindex) @@ -701,7 +701,7 @@ probe_helper_for_progtype(enum bpf_prog_type prog_type, bool supported_type, if (ifindex) res = probe_helper_ifindex(id, prog_type, ifindex); else - res = libbpf_probe_bpf_helper(prog_type, id, NULL); + res = libbpf_probe_bpf_helper(prog_type, id, NULL) > 0; #ifdef USE_LIBCAP /* Probe may succeed even if program load fails, for * unprivileged users check that we did not fail because of @@ -723,6 +723,8 @@ probe_helper_for_progtype(enum bpf_prog_type prog_type, bool supported_type, if (res) printf("\n\t- %s", helper_name[id]); } + + return res; } static void @@ -732,6 +734,7 @@ probe_helpers_for_progtype(enum bpf_prog_type prog_type, bool supported_type, const char *ptype_name = prog_type_name[prog_type]; char feat_name[128]; unsigned int id; + bool probe_res = false; if (ifindex) /* Only test helpers for offload-able program types */ @@ -764,7 +767,7 @@ probe_helpers_for_progtype(enum bpf_prog_type prog_type, bool supported_type, continue; /* fallthrough */ default: - probe_helper_for_progtype(prog_type, supported_type, + probe_res |= probe_helper_for_progtype(prog_type, supported_type, define_prefix, id, ptype_name, ifindex); } @@ -772,8 +775,17 @@ probe_helpers_for_progtype(enum bpf_prog_type prog_type, bool supported_type, if (json_output) jsonw_end_array(json_wtr); - else if (!define_prefix) + else if (!define_prefix) { printf("\n"); + if (!probe_res) { + if (!supported_type) + printf("\tProgram type not supported\n"); + else + printf("\tCould not determine which helpers are available\n"); + } + } + + } static void |