This change introduces a new positional argument "section" which takes the following arguments:
- system_config - syscall_config - program_types - map_types - helpers - misc
If "section" argument is defined, only that particular section is going to be probed and printed. The only section which is always going to be probed is "syscall_config", but if the other section was provided as an argument, "syscall_config" check will perform silently without printing and exit bpftool if the bpf() syscall is not available (because in that case running any probe has no sense).
Signed-off-by: Michal Rostecki mrostecki@opensuse.org --- tools/bpf/bpftool/feature.c | 159 ++++++++++++++++++++++++++++-------- 1 file changed, 123 insertions(+), 36 deletions(-)
diff --git a/tools/bpf/bpftool/feature.c b/tools/bpf/bpftool/feature.c index 345e4a2b4f53..cfba0faf148f 100644 --- a/tools/bpf/bpftool/feature.c +++ b/tools/bpf/bpftool/feature.c @@ -22,6 +22,13 @@ # define PROC_SUPER_MAGIC 0x9fa0 #endif
+#define SECTION_SYSCALL_CONFIG "syscall_config" +#define SECTION_SYSTEM_CONFIG "system_config" +#define SECTION_PROGRAM_TYPES "program_types" +#define SECTION_MAP_TYPES "map_types" +#define SECTION_HELPERS "helpers" +#define SECTION_MISC "misc" + enum probe_component { COMPONENT_UNSPEC, COMPONENT_KERNEL, @@ -436,24 +443,26 @@ static void probe_kernel_image_config(void) } }
-static bool probe_bpf_syscall(const char *define_prefix) +static bool +probe_bpf_syscall(bool print_syscall_config, const char *define_prefix) { bool res;
bpf_load_program(BPF_PROG_TYPE_UNSPEC, NULL, 0, NULL, 0, NULL, 0); res = (errno != ENOSYS);
- print_bool_feature("have_bpf_syscall", - "bpf() syscall", - "BPF_SYSCALL", - res, define_prefix); + if (print_syscall_config) + print_bool_feature("have_bpf_syscall", + "bpf() syscall", + "BPF_SYSCALL", + res, define_prefix);
return res; }
static void -probe_prog_type(enum bpf_prog_type prog_type, bool *supported_types, - const char *define_prefix, __u32 ifindex) +probe_prog_type(bool print_program_types, enum bpf_prog_type prog_type, + bool *supported_types, const char *define_prefix, __u32 ifindex) { char feat_name[128], plain_desc[128], define_name[128]; const char *plain_comment = "eBPF program_type "; @@ -484,8 +493,10 @@ probe_prog_type(enum bpf_prog_type prog_type, bool *supported_types, sprintf(define_name, "%s_prog_type", prog_type_name[prog_type]); uppercase(define_name, sizeof(define_name)); sprintf(plain_desc, "%s%s", plain_comment, prog_type_name[prog_type]); - print_bool_feature(feat_name, plain_desc, define_name, res, - define_prefix); + + if (print_program_types) + print_bool_feature(feat_name, plain_desc, define_name, res, + define_prefix); }
static void @@ -587,7 +598,7 @@ section_system_config(enum probe_component target, const char *define_prefix) if (define_prefix) break;
- print_start_section("system_config", + print_start_section(SECTION_SYSTEM_CONFIG, "Scanning system configuration...", NULL, /* define_comment never used here */ NULL); /* define_prefix always NULL here */ @@ -608,42 +619,48 @@ section_system_config(enum probe_component target, const char *define_prefix) } }
-static bool section_syscall_config(const char *define_prefix) +static bool +section_syscall_config(bool print_syscall_config, const char *define_prefix) { bool res;
- print_start_section("syscall_config", - "Scanning system call availability...", - "/*** System call availability ***/", - define_prefix); - res = probe_bpf_syscall(define_prefix); - print_end_section(); + if (print_syscall_config) + print_start_section(SECTION_SYSCALL_CONFIG, + "Scanning system call availability...", + "/*** System call availability ***/", + define_prefix); + res = probe_bpf_syscall(print_syscall_config, define_prefix); + if (print_syscall_config) + print_end_section();
return res; }
static void -section_program_types(bool *supported_types, const char *define_prefix, - __u32 ifindex) +section_program_types(bool print_program_types, bool *supported_types, + const char *define_prefix, __u32 ifindex) { unsigned int i;
- print_start_section("program_types", - "Scanning eBPF program types...", - "/*** eBPF program types ***/", - define_prefix); + if (print_program_types) + print_start_section(SECTION_PROGRAM_TYPES, + "Scanning eBPF program types...", + "/*** eBPF program types ***/", + define_prefix);
for (i = BPF_PROG_TYPE_UNSPEC + 1; i < ARRAY_SIZE(prog_type_name); i++) - probe_prog_type(i, supported_types, define_prefix, ifindex); + probe_prog_type(print_program_types, i, supported_types, + define_prefix, ifindex);
- print_end_section(); + if (print_program_types) + print_end_section(); }
static void section_map_types(const char *define_prefix, __u32 ifindex) { unsigned int i;
- print_start_section("map_types", + print_start_section(SECTION_MAP_TYPES, "Scanning eBPF map types...", "/*** eBPF map types ***/", define_prefix); @@ -659,7 +676,7 @@ section_helpers(bool *supported_types, const char *define_prefix, __u32 ifindex) { unsigned int i;
- print_start_section("helpers", + print_start_section(SECTION_HELPERS, "Scanning eBPF helper functions...", "/*** eBPF helper functions ***/", define_prefix); @@ -688,7 +705,7 @@ section_helpers(bool *supported_types, const char *define_prefix, __u32 ifindex)
static void section_misc(const char *define_prefix, __u32 ifindex) { - print_start_section("misc", + print_start_section(SECTION_MISC, "Scanning miscellaneous eBPF features...", "/*** eBPF misc features ***/", define_prefix); @@ -699,8 +716,25 @@ static void section_misc(const char *define_prefix, __u32 ifindex) static int do_probe(int argc, char **argv) { enum probe_component target = COMPONENT_UNSPEC; + /* Syscall probe is always performed, because performing any other + * checks without bpf() syscall does not make sense and the program + * should exit. + */ + bool print_syscall_config = false; const char *define_prefix = NULL; + bool check_system_config = false; + /* Program types probes are needed if helper probes are going to be + * performed. Therefore we should differentiate between checking and + * printing supported program types. If only helper checks were + * requested, program types probes will be performed, but not printed. + */ + bool check_program_types = false; + bool print_program_types = false; bool supported_types[128] = {}; + bool check_map_types = false; + bool check_helpers = false; + bool check_section = false; + bool check_misc = false; __u32 ifindex = 0; char *ifname;
@@ -740,6 +774,39 @@ static int do_probe(int argc, char **argv) strerror(errno)); return -1; } + } else if (is_prefix(*argv, "section")) { + check_section = true; + NEXT_ARG(); + if (is_prefix(*argv, SECTION_SYSTEM_CONFIG)) { + check_system_config = true; + } else if (is_prefix(*argv, SECTION_SYSCALL_CONFIG)) { + print_syscall_config = true; + } else if (is_prefix(*argv, SECTION_PROGRAM_TYPES)) { + check_program_types = true; + print_program_types = true; + } else if (is_prefix(*argv, SECTION_MAP_TYPES)) { + check_map_types = true; + } else if (is_prefix(*argv, SECTION_HELPERS)) { + /* When helpers probes are requested, program + * types probes have to be performed, but they + * may not be printed. + */ + check_program_types = true; + check_helpers = true; + } else if (is_prefix(*argv, SECTION_MISC)) { + check_misc = true; + } else { + p_err("unrecognized section '%s', available sections: %s, %s, %s, %s, %s, %s", + *argv, + SECTION_SYSTEM_CONFIG, + SECTION_SYSCALL_CONFIG, + SECTION_PROGRAM_TYPES, + SECTION_MAP_TYPES, + SECTION_HELPERS, + SECTION_MISC); + return -1; + } + NEXT_ARG(); } else if (is_prefix(*argv, "macros") && !define_prefix) { define_prefix = ""; NEXT_ARG(); @@ -764,19 +831,36 @@ static int do_probe(int argc, char **argv) } }
+ /* Perform all checks if specific section check was not requested. */ + if (!check_section) { + print_syscall_config = true; + check_system_config = true; + check_program_types = true; + print_program_types = true; + check_map_types = true; + check_helpers = true; + check_misc = true; + } + if (json_output) { define_prefix = NULL; jsonw_start_object(json_wtr); }
- section_system_config(target, define_prefix); - if (!section_syscall_config(define_prefix)) + if (check_system_config) + section_system_config(target, define_prefix); + if (!section_syscall_config(print_syscall_config, define_prefix)) /* bpf() syscall unavailable, don't probe other BPF features */ goto exit_close_json; - section_program_types(supported_types, define_prefix, ifindex); - section_map_types(define_prefix, ifindex); - section_helpers(supported_types, define_prefix, ifindex); - section_misc(define_prefix, ifindex); + if (check_program_types) + section_program_types(print_program_types, supported_types, + define_prefix, ifindex); + if (check_map_types) + section_map_types(define_prefix, ifindex); + if (check_helpers) + section_helpers(supported_types, define_prefix, ifindex); + if (check_misc) + section_misc(define_prefix, ifindex);
exit_close_json: if (json_output) @@ -794,12 +878,15 @@ static int do_help(int argc, char **argv) }
fprintf(stderr, - "Usage: %s %s probe [COMPONENT] [macros [prefix PREFIX]]\n" + "Usage: %s %s probe [COMPONENT] [section SECTION] [macros [prefix PREFIX]]\n" " %s %s help\n" "\n" " COMPONENT := { kernel | dev NAME }\n" + " SECTION := { %s | %s | %s | %s | %s | %s }\n" "", - bin_name, argv[-2], bin_name, argv[-2]); + bin_name, argv[-2], bin_name, argv[-2], SECTION_SYSTEM_CONFIG, + SECTION_SYSCALL_CONFIG, SECTION_PROGRAM_TYPES, + SECTION_MAP_TYPES, SECTION_HELPERS, SECTION_MISC);
return 0; }