From 58650cc47382af7d87282f53a5b508ac4bf734af Mon Sep 17 00:00:00 2001 From: Andrii Nakryiko Date: Fri, 24 May 2019 11:58:58 -0700 Subject: bpftool: use libbpf's btf__parse_elf API Use btf__parse_elf() API, provided by libbpf, instead of implementing ELF parsing by itself. Signed-off-by: Andrii Nakryiko Signed-off-by: Alexei Starovoitov --- tools/bpf/bpftool/btf.c | 117 ++++-------------------------------------------- 1 file changed, 8 insertions(+), 109 deletions(-) (limited to 'tools/bpf/bpftool') diff --git a/tools/bpf/bpftool/btf.c b/tools/bpf/bpftool/btf.c index 7317438ecd9e..a22ef6587ebe 100644 --- a/tools/bpf/bpftool/btf.c +++ b/tools/bpf/bpftool/btf.c @@ -8,8 +8,8 @@ #include #include #include -#include #include +#include #include #include "btf.h" @@ -340,112 +340,6 @@ static int dump_btf_raw(const struct btf *btf, return 0; } -static bool check_btf_endianness(GElf_Ehdr *ehdr) -{ - static unsigned int const endian = 1; - - switch (ehdr->e_ident[EI_DATA]) { - case ELFDATA2LSB: - return *(unsigned char const *)&endian == 1; - case ELFDATA2MSB: - return *(unsigned char const *)&endian == 0; - default: - return 0; - } -} - -static int btf_load_from_elf(const char *path, struct btf **btf) -{ - int err = -1, fd = -1, idx = 0; - Elf_Data *btf_data = NULL; - Elf_Scn *scn = NULL; - Elf *elf = NULL; - GElf_Ehdr ehdr; - - if (elf_version(EV_CURRENT) == EV_NONE) { - p_err("failed to init libelf for %s", path); - return -1; - } - - fd = open(path, O_RDONLY); - if (fd < 0) { - p_err("failed to open %s: %s", path, strerror(errno)); - return -1; - } - - elf = elf_begin(fd, ELF_C_READ, NULL); - if (!elf) { - p_err("failed to open %s as ELF file", path); - goto done; - } - if (!gelf_getehdr(elf, &ehdr)) { - p_err("failed to get EHDR from %s", path); - goto done; - } - if (!check_btf_endianness(&ehdr)) { - p_err("non-native ELF endianness is not supported"); - goto done; - } - if (!elf_rawdata(elf_getscn(elf, ehdr.e_shstrndx), NULL)) { - p_err("failed to get e_shstrndx from %s\n", path); - goto done; - } - - while ((scn = elf_nextscn(elf, scn)) != NULL) { - GElf_Shdr sh; - char *name; - - idx++; - if (gelf_getshdr(scn, &sh) != &sh) { - p_err("failed to get section(%d) header from %s", - idx, path); - goto done; - } - name = elf_strptr(elf, ehdr.e_shstrndx, sh.sh_name); - if (!name) { - p_err("failed to get section(%d) name from %s", - idx, path); - goto done; - } - if (strcmp(name, BTF_ELF_SEC) == 0) { - btf_data = elf_getdata(scn, 0); - if (!btf_data) { - p_err("failed to get section(%d, %s) data from %s", - idx, name, path); - goto done; - } - break; - } - } - - if (!btf_data) { - p_err("%s ELF section not found in %s", BTF_ELF_SEC, path); - goto done; - } - - *btf = btf__new(btf_data->d_buf, btf_data->d_size); - if (IS_ERR(*btf)) { - err = PTR_ERR(*btf); - *btf = NULL; - p_err("failed to load BTF data from %s: %s", - path, strerror(err)); - goto done; - } - - err = 0; -done: - if (err) { - if (*btf) { - btf__free(*btf); - *btf = NULL; - } - } - if (elf) - elf_end(elf); - close(fd); - return err; -} - static int do_dump(int argc, char **argv) { struct btf *btf = NULL; @@ -522,9 +416,14 @@ static int do_dump(int argc, char **argv) } NEXT_ARG(); } else if (is_prefix(src, "file")) { - err = btf_load_from_elf(*argv, &btf); - if (err) + btf = btf__parse_elf(*argv, NULL); + if (IS_ERR(btf)) { + err = PTR_ERR(btf); + btf = NULL; + p_err("failed to load BTF from %s: %s", + *argv, strerror(err)); goto done; + } NEXT_ARG(); } else { err = -1; -- cgit From 2119f2189df1836d28909fe5a90b3d93638ecf65 Mon Sep 17 00:00:00 2001 From: Andrii Nakryiko Date: Fri, 24 May 2019 11:59:05 -0700 Subject: bpftool: add C output format option to btf dump subcommand Utilize new libbpf's btf_dump API to emit BTF as a C definitions. Acked-by: Jakub Kicinski Signed-off-by: Andrii Nakryiko Reviewed-by: Quentin Monnet Signed-off-by: Alexei Starovoitov --- tools/bpf/bpftool/btf.c | 75 +++++++++++++++++++++++++++++++++++++++++++++++-- 1 file changed, 73 insertions(+), 2 deletions(-) (limited to 'tools/bpf/bpftool') diff --git a/tools/bpf/bpftool/btf.c b/tools/bpf/bpftool/btf.c index a22ef6587ebe..1b8ec91899e6 100644 --- a/tools/bpf/bpftool/btf.c +++ b/tools/bpf/bpftool/btf.c @@ -340,11 +340,49 @@ static int dump_btf_raw(const struct btf *btf, return 0; } +static void __printf(2, 0) btf_dump_printf(void *ctx, + const char *fmt, va_list args) +{ + vfprintf(stdout, fmt, args); +} + +static int dump_btf_c(const struct btf *btf, + __u32 *root_type_ids, int root_type_cnt) +{ + struct btf_dump *d; + int err = 0, i; + + d = btf_dump__new(btf, NULL, NULL, btf_dump_printf); + if (IS_ERR(d)) + return PTR_ERR(d); + + if (root_type_cnt) { + for (i = 0; i < root_type_cnt; i++) { + err = btf_dump__dump_type(d, root_type_ids[i]); + if (err) + goto done; + } + } else { + int cnt = btf__get_nr_types(btf); + + for (i = 1; i <= cnt; i++) { + err = btf_dump__dump_type(d, i); + if (err) + goto done; + } + } + +done: + btf_dump__free(d); + return err; +} + static int do_dump(int argc, char **argv) { struct btf *btf = NULL; __u32 root_type_ids[2]; int root_type_cnt = 0; + bool dump_c = false; __u32 btf_id = -1; const char *src; int fd = -1; @@ -431,6 +469,29 @@ static int do_dump(int argc, char **argv) goto done; } + while (argc) { + if (is_prefix(*argv, "format")) { + NEXT_ARG(); + if (argc < 1) { + p_err("expecting value for 'format' option\n"); + goto done; + } + if (strcmp(*argv, "c") == 0) { + dump_c = true; + } else if (strcmp(*argv, "raw") == 0) { + dump_c = false; + } else { + p_err("unrecognized format specifier: '%s', possible values: raw, c", + *argv); + goto done; + } + NEXT_ARG(); + } else { + p_err("unrecognized option: '%s'", *argv); + goto done; + } + } + if (!btf) { err = btf__get_from_id(btf_id, &btf); if (err) { @@ -444,7 +505,16 @@ static int do_dump(int argc, char **argv) } } - dump_btf_raw(btf, root_type_ids, root_type_cnt); + if (dump_c) { + if (json_output) { + p_err("JSON output for C-syntax dump is not supported"); + err = -ENOTSUP; + goto done; + } + err = dump_btf_c(btf, root_type_ids, root_type_cnt); + } else { + err = dump_btf_raw(btf, root_type_ids, root_type_cnt); + } done: close(fd); @@ -460,10 +530,11 @@ static int do_help(int argc, char **argv) } fprintf(stderr, - "Usage: %s btf dump BTF_SRC\n" + "Usage: %s btf dump BTF_SRC [format FORMAT]\n" " %s btf help\n" "\n" " BTF_SRC := { id BTF_ID | prog PROG | map MAP [{key | value | kv | all}] | file FILE }\n" + " FORMAT := { raw | c }\n" " " HELP_SPEC_MAP "\n" " " HELP_SPEC_PROGRAM "\n" " " HELP_SPEC_OPTIONS "\n" -- cgit From 220ba451124e275ff548bec33b0dc01e40895b06 Mon Sep 17 00:00:00 2001 From: Andrii Nakryiko Date: Fri, 24 May 2019 11:59:06 -0700 Subject: bpftool/docs: add description of btf dump C option Document optional **c** option for btf dump subcommand. Cc: Quentin Monnet Signed-off-by: Andrii Nakryiko Reviewed-by: Quentin Monnet Signed-off-by: Alexei Starovoitov --- tools/bpf/bpftool/Documentation/bpftool-btf.rst | 35 ++++++++++++++----------- 1 file changed, 20 insertions(+), 15 deletions(-) (limited to 'tools/bpf/bpftool') diff --git a/tools/bpf/bpftool/Documentation/bpftool-btf.rst b/tools/bpf/bpftool/Documentation/bpftool-btf.rst index 2dbc1413fabd..3daed9eba766 100644 --- a/tools/bpf/bpftool/Documentation/bpftool-btf.rst +++ b/tools/bpf/bpftool/Documentation/bpftool-btf.rst @@ -19,10 +19,11 @@ SYNOPSIS BTF COMMANDS ============= -| **bpftool** **btf dump** *BTF_SRC* +| **bpftool** **btf dump** *BTF_SRC* [**format** *FORMAT*] | **bpftool** **btf help** | | *BTF_SRC* := { **id** *BTF_ID* | **prog** *PROG* | **map** *MAP* [{**key** | **value** | **kv** | **all**}] | **file** *FILE* } +| *FORMAT* := { **raw** | **c** } | *MAP* := { **id** *MAP_ID* | **pinned** *FILE* } | *PROG* := { **id** *PROG_ID* | **pinned** *FILE* | **tag** *PROG_TAG* } @@ -31,23 +32,27 @@ DESCRIPTION **bpftool btf dump** *BTF_SRC* Dump BTF entries from a given *BTF_SRC*. - When **id** is specified, BTF object with that ID will be - loaded and all its BTF types emitted. + When **id** is specified, BTF object with that ID will be + loaded and all its BTF types emitted. - When **map** is provided, it's expected that map has - associated BTF object with BTF types describing key and - value. It's possible to select whether to dump only BTF - type(s) associated with key (**key**), value (**value**), - both key and value (**kv**), or all BTF types present in - associated BTF object (**all**). If not specified, **kv** - is assumed. + When **map** is provided, it's expected that map has + associated BTF object with BTF types describing key and + value. It's possible to select whether to dump only BTF + type(s) associated with key (**key**), value (**value**), + both key and value (**kv**), or all BTF types present in + associated BTF object (**all**). If not specified, **kv** + is assumed. - When **prog** is provided, it's expected that program has - associated BTF object with BTF types. + When **prog** is provided, it's expected that program has + associated BTF object with BTF types. - When specifying *FILE*, an ELF file is expected, containing - .BTF section with well-defined BTF binary format data, - typically produced by clang or pahole. + When specifying *FILE*, an ELF file is expected, containing + .BTF section with well-defined BTF binary format data, + typically produced by clang or pahole. + + **format** option can be used to override default (raw) + output format. Raw (**raw**) or C-syntax (**c**) output + formats are supported. **bpftool btf help** Print short help message. -- cgit From 90eea4086d5ed31936889a44d536bf77afa4ca8a Mon Sep 17 00:00:00 2001 From: Andrii Nakryiko Date: Fri, 24 May 2019 11:59:07 -0700 Subject: bpftool: update bash-completion w/ new c option for btf dump Add bash completion for new C btf dump option. Cc: Quentin Monnet Signed-off-by: Andrii Nakryiko Reviewed-by: Quentin Monnet Signed-off-by: Alexei Starovoitov --- tools/bpf/bpftool/bash-completion/bpftool | 21 +++++++++++++++++---- 1 file changed, 17 insertions(+), 4 deletions(-) (limited to 'tools/bpf/bpftool') diff --git a/tools/bpf/bpftool/bash-completion/bpftool b/tools/bpf/bpftool/bash-completion/bpftool index 50e402a5a9c8..75c01eafd3a1 100644 --- a/tools/bpf/bpftool/bash-completion/bpftool +++ b/tools/bpf/bpftool/bash-completion/bpftool @@ -638,11 +638,24 @@ _bpftool() esac return 0 ;; + format) + COMPREPLY=( $( compgen -W "c raw" -- "$cur" ) ) + ;; *) - if [[ $cword == 6 ]] && [[ ${words[3]} == "map" ]]; then - COMPREPLY+=( $( compgen -W 'key value kv all' -- \ - "$cur" ) ) - fi + # emit extra options + case ${words[3]} in + id|file) + _bpftool_once_attr 'format' + ;; + map|prog) + if [[ ${words[3]} == "map" ]] && [[ $cword == 6 ]]; then + COMPREPLY+=( $( compgen -W "key value kv all" -- "$cur" ) ) + fi + _bpftool_once_attr 'format' + ;; + *) + ;; + esac return 0 ;; esac -- cgit From 0d97dacc46d9af2daba1af224747d452bd988365 Mon Sep 17 00:00:00 2001 From: Andrii Nakryiko Date: Sat, 25 May 2019 17:01:01 -0700 Subject: bpftool: auto-complete BTF IDs for btf dump Auto-complete BTF IDs for `btf dump id` sub-command. List of possible BTF IDs is scavenged from loaded BPF programs that have associated BTFs, as there is currently no API in libbpf to fetch list of all BTFs in the system. Suggested-by: Quentin Monnet Signed-off-by: Andrii Nakryiko Reviewed-by: Quentin Monnet Signed-off-by: Daniel Borkmann --- tools/bpf/bpftool/bash-completion/bpftool | 9 +++++++++ 1 file changed, 9 insertions(+) (limited to 'tools/bpf/bpftool') diff --git a/tools/bpf/bpftool/bash-completion/bpftool b/tools/bpf/bpftool/bash-completion/bpftool index 75c01eafd3a1..fbbad0ed8e82 100644 --- a/tools/bpf/bpftool/bash-completion/bpftool +++ b/tools/bpf/bpftool/bash-completion/bpftool @@ -71,6 +71,12 @@ _bpftool_get_prog_tags() command sed -n 's/.*"tag": "\(.*\)",$/\1/p' )" -- "$cur" ) ) } +_bpftool_get_btf_ids() +{ + COMPREPLY+=( $( compgen -W "$( bpftool -jp prog 2>&1 | \ + command sed -n 's/.*"btf_id": \(.*\),\?$/\1/p' )" -- "$cur" ) ) +} + _bpftool_get_obj_map_names() { local obj @@ -635,6 +641,9 @@ _bpftool() map) _bpftool_get_map_ids ;; + dump) + _bpftool_get_btf_ids + ;; esac return 0 ;; -- cgit From 92bd6820f2b11c2decdd92e1f9020e804dbc2ed1 Mon Sep 17 00:00:00 2001 From: Chang-Hsien Tsai Date: Sun, 26 May 2019 10:32:11 +0000 Subject: bpf: style fix in while(!feof()) loop Use fgets() as the while loop condition. Signed-off-by: Chang-Hsien Tsai Acked-by: Yonghong Song Signed-off-by: Daniel Borkmann --- tools/bpf/bpftool/xlated_dumper.c | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-) (limited to 'tools/bpf/bpftool') diff --git a/tools/bpf/bpftool/xlated_dumper.c b/tools/bpf/bpftool/xlated_dumper.c index 0bb17bf88b18..494d7ae3614d 100644 --- a/tools/bpf/bpftool/xlated_dumper.c +++ b/tools/bpf/bpftool/xlated_dumper.c @@ -31,9 +31,7 @@ void kernel_syms_load(struct dump_data *dd) if (!fp) return; - while (!feof(fp)) { - if (!fgets(buff, sizeof(buff), fp)) - break; + while (fgets(buff, sizeof(buff), fp)) { tmp = reallocarray(dd->sym_mapping, dd->sym_count + 1, sizeof(*dd->sym_mapping)); if (!tmp) { -- cgit From 775bc8ada89b376b4bbbce31aba47f4117fe1d9c Mon Sep 17 00:00:00 2001 From: Quentin Monnet Date: Fri, 24 May 2019 11:36:46 +0100 Subject: tools: bpftool: add -d option to get debug output from libbpf libbpf has three levels of priority for output messages: warn, info, debug. By default, debug output is not printed to the console. Add a new "--debug" (short name: "-d") option to bpftool to print libbpf logs for all three levels. Internally, we simply use the function provided by libbpf to replace the default printing function by one that prints logs regardless of their level. v2: - Remove the possibility to select the log-levels to use (v1 offered a combination of "warn", "info" and "debug"). - Rename option and offer a short name: -d|--debug. - Add option description to all bpftool manual pages (instead of bpftool-prog.rst only), as all commands use libbpf. Signed-off-by: Quentin Monnet Reviewed-by: Jakub Kicinski Signed-off-by: Daniel Borkmann --- tools/bpf/bpftool/Documentation/bpftool-btf.rst | 4 ++++ tools/bpf/bpftool/Documentation/bpftool-cgroup.rst | 4 ++++ tools/bpf/bpftool/Documentation/bpftool-feature.rst | 4 ++++ tools/bpf/bpftool/Documentation/bpftool-map.rst | 4 ++++ tools/bpf/bpftool/Documentation/bpftool-net.rst | 4 ++++ tools/bpf/bpftool/Documentation/bpftool-perf.rst | 4 ++++ tools/bpf/bpftool/Documentation/bpftool-prog.rst | 4 ++++ tools/bpf/bpftool/Documentation/bpftool.rst | 3 +++ tools/bpf/bpftool/bash-completion/bpftool | 2 +- tools/bpf/bpftool/main.c | 14 +++++++++++++- 10 files changed, 45 insertions(+), 2 deletions(-) (limited to 'tools/bpf/bpftool') diff --git a/tools/bpf/bpftool/Documentation/bpftool-btf.rst b/tools/bpf/bpftool/Documentation/bpftool-btf.rst index 3daed9eba766..6694a0fc8f99 100644 --- a/tools/bpf/bpftool/Documentation/bpftool-btf.rst +++ b/tools/bpf/bpftool/Documentation/bpftool-btf.rst @@ -72,6 +72,10 @@ OPTIONS -p, --pretty Generate human-readable JSON output. Implies **-j**. + -d, --debug + Print all logs available from libbpf, including debug-level + information. + EXAMPLES ======== **# bpftool btf dump id 1226** diff --git a/tools/bpf/bpftool/Documentation/bpftool-cgroup.rst b/tools/bpf/bpftool/Documentation/bpftool-cgroup.rst index ac26876389c2..36807735e2a5 100644 --- a/tools/bpf/bpftool/Documentation/bpftool-cgroup.rst +++ b/tools/bpf/bpftool/Documentation/bpftool-cgroup.rst @@ -113,6 +113,10 @@ OPTIONS -f, --bpffs Show file names of pinned programs. + -d, --debug + Print all logs available from libbpf, including debug-level + information. + EXAMPLES ======== | diff --git a/tools/bpf/bpftool/Documentation/bpftool-feature.rst b/tools/bpf/bpftool/Documentation/bpftool-feature.rst index 14180e887082..4d08f35034a2 100644 --- a/tools/bpf/bpftool/Documentation/bpftool-feature.rst +++ b/tools/bpf/bpftool/Documentation/bpftool-feature.rst @@ -73,6 +73,10 @@ OPTIONS -p, --pretty Generate human-readable JSON output. Implies **-j**. + -d, --debug + Print all logs available from libbpf, including debug-level + information. + SEE ALSO ======== **bpf**\ (2), diff --git a/tools/bpf/bpftool/Documentation/bpftool-map.rst b/tools/bpf/bpftool/Documentation/bpftool-map.rst index 13ef27b39f20..490b4501cb6e 100644 --- a/tools/bpf/bpftool/Documentation/bpftool-map.rst +++ b/tools/bpf/bpftool/Documentation/bpftool-map.rst @@ -152,6 +152,10 @@ OPTIONS Do not automatically attempt to mount any virtual file system (such as tracefs or BPF virtual file system) when necessary. + -d, --debug + Print all logs available from libbpf, including debug-level + information. + EXAMPLES ======== **# bpftool map show** diff --git a/tools/bpf/bpftool/Documentation/bpftool-net.rst b/tools/bpf/bpftool/Documentation/bpftool-net.rst index 934580850f42..d8e5237a2085 100644 --- a/tools/bpf/bpftool/Documentation/bpftool-net.rst +++ b/tools/bpf/bpftool/Documentation/bpftool-net.rst @@ -65,6 +65,10 @@ OPTIONS -p, --pretty Generate human-readable JSON output. Implies **-j**. + -d, --debug + Print all logs available from libbpf, including debug-level + information. + EXAMPLES ======== diff --git a/tools/bpf/bpftool/Documentation/bpftool-perf.rst b/tools/bpf/bpftool/Documentation/bpftool-perf.rst index 0c7576523a21..e252bd0bc434 100644 --- a/tools/bpf/bpftool/Documentation/bpftool-perf.rst +++ b/tools/bpf/bpftool/Documentation/bpftool-perf.rst @@ -53,6 +53,10 @@ OPTIONS -p, --pretty Generate human-readable JSON output. Implies **-j**. + -d, --debug + Print all logs available from libbpf, including debug-level + information. + EXAMPLES ======== diff --git a/tools/bpf/bpftool/Documentation/bpftool-prog.rst b/tools/bpf/bpftool/Documentation/bpftool-prog.rst index e8118544d118..9a92614569e6 100644 --- a/tools/bpf/bpftool/Documentation/bpftool-prog.rst +++ b/tools/bpf/bpftool/Documentation/bpftool-prog.rst @@ -174,6 +174,10 @@ OPTIONS Do not automatically attempt to mount any virtual file system (such as tracefs or BPF virtual file system) when necessary. + -d, --debug + Print all logs available from libbpf, including debug-level + information. + EXAMPLES ======== **# bpftool prog show** diff --git a/tools/bpf/bpftool/Documentation/bpftool.rst b/tools/bpf/bpftool/Documentation/bpftool.rst index 3e562d7fd56f..43dba0717953 100644 --- a/tools/bpf/bpftool/Documentation/bpftool.rst +++ b/tools/bpf/bpftool/Documentation/bpftool.rst @@ -66,6 +66,9 @@ OPTIONS Do not automatically attempt to mount any virtual file system (such as tracefs or BPF virtual file system) when necessary. + -d, --debug + Print all logs available from libbpf, including debug-level + information. SEE ALSO ======== diff --git a/tools/bpf/bpftool/bash-completion/bpftool b/tools/bpf/bpftool/bash-completion/bpftool index fbbad0ed8e82..2725e27dfa42 100644 --- a/tools/bpf/bpftool/bash-completion/bpftool +++ b/tools/bpf/bpftool/bash-completion/bpftool @@ -187,7 +187,7 @@ _bpftool() # Deal with options if [[ ${words[cword]} == -* ]]; then - local c='--version --json --pretty --bpffs --mapcompat' + local c='--version --json --pretty --bpffs --mapcompat --debug' COMPREPLY=( $( compgen -W "$c" -- "$cur" ) ) return 0 fi diff --git a/tools/bpf/bpftool/main.c b/tools/bpf/bpftool/main.c index 1ac1fc520e6a..d74293938a05 100644 --- a/tools/bpf/bpftool/main.c +++ b/tools/bpf/bpftool/main.c @@ -10,6 +10,7 @@ #include #include +#include #include "main.h" @@ -77,6 +78,13 @@ static int do_version(int argc, char **argv) return 0; } +static int __printf(2, 0) +print_all_levels(__maybe_unused enum libbpf_print_level level, + const char *format, va_list args) +{ + return vfprintf(stderr, format, args); +} + int cmd_select(const struct cmd *cmds, int argc, char **argv, int (*help)(int argc, char **argv)) { @@ -317,6 +325,7 @@ int main(int argc, char **argv) { "bpffs", no_argument, NULL, 'f' }, { "mapcompat", no_argument, NULL, 'm' }, { "nomount", no_argument, NULL, 'n' }, + { "debug", no_argument, NULL, 'd' }, { 0 } }; int opt, ret; @@ -332,7 +341,7 @@ int main(int argc, char **argv) hash_init(map_table.table); opterr = 0; - while ((opt = getopt_long(argc, argv, "Vhpjfmn", + while ((opt = getopt_long(argc, argv, "Vhpjfmnd", options, NULL)) >= 0) { switch (opt) { case 'V': @@ -362,6 +371,9 @@ int main(int argc, char **argv) case 'n': block_mount = true; break; + case 'd': + libbpf_set_print(print_all_levels); + break; default: p_err("unrecognized option '%s'", argv[optind - 1]); if (json_output) -- cgit From 55d778076b0354b088a9a16d9ff584c887e17f42 Mon Sep 17 00:00:00 2001 From: Quentin Monnet Date: Fri, 24 May 2019 11:36:48 +0100 Subject: tools: bpftool: make -d option print debug output from verifier The "-d" option is used to require all logs available for bpftool. So far it meant telling libbpf to print even debug-level information. But there is another source of info that can be made more verbose: when we attemt to load programs with bpftool, we can pass a log_level parameter to the verifier in order to control the amount of information that is printed to the console. Reuse the "-d" option to print all information the verifier can tell. At this time, this means logs related to BPF_LOG_LEVEL1, BPF_LOG_LEVEL2 and BPF_LOG_STATS. As mentioned in the discussion on the first version of this set, these macros are internal to the kernel (include/linux/bpf_verifier.h) and are not meant to be part of the stable user API, therefore we simply use the related constants to print whatever we can at this time, without trying to tell users what is log_level1 or what is statistics. Verifier logs are only used when loading programs for now (In the future: for loading BTF objects with bpftool? Although libbpf does not currently offer to print verifier info at debug level if no error occurred when loading BTF objects), so bpftool.rst and bpftool-prog.rst are the only man pages to get the update. v3: - Add details on log level and BTF loading at the end of commit log. v2: - Remove the possibility to select the log levels to use (v1 offered a combination of "log_level1", "log_level2" and "stats"). - The macros from kernel header bpf_verifier.h are not used (and therefore not moved to UAPI header). - In v1 this was a distinct option, but is now merged in the only "-d" switch to activate libbpf and verifier debug-level logs all at the same time. Signed-off-by: Quentin Monnet Reviewed-by: Jakub Kicinski Signed-off-by: Daniel Borkmann --- tools/bpf/bpftool/Documentation/bpftool-prog.rst | 5 +++-- tools/bpf/bpftool/Documentation/bpftool.rst | 5 +++-- tools/bpf/bpftool/main.c | 2 ++ tools/bpf/bpftool/main.h | 1 + tools/bpf/bpftool/prog.c | 27 +++++++++++++++--------- 5 files changed, 26 insertions(+), 14 deletions(-) (limited to 'tools/bpf/bpftool') diff --git a/tools/bpf/bpftool/Documentation/bpftool-prog.rst b/tools/bpf/bpftool/Documentation/bpftool-prog.rst index 9a92614569e6..228a5c863cc7 100644 --- a/tools/bpf/bpftool/Documentation/bpftool-prog.rst +++ b/tools/bpf/bpftool/Documentation/bpftool-prog.rst @@ -175,8 +175,9 @@ OPTIONS (such as tracefs or BPF virtual file system) when necessary. -d, --debug - Print all logs available from libbpf, including debug-level - information. + Print all logs available, even debug-level information. This + includes logs from libbpf as well as from the verifier, when + attempting to load programs. EXAMPLES ======== diff --git a/tools/bpf/bpftool/Documentation/bpftool.rst b/tools/bpf/bpftool/Documentation/bpftool.rst index 43dba0717953..6a9c52ef84a9 100644 --- a/tools/bpf/bpftool/Documentation/bpftool.rst +++ b/tools/bpf/bpftool/Documentation/bpftool.rst @@ -67,8 +67,9 @@ OPTIONS (such as tracefs or BPF virtual file system) when necessary. -d, --debug - Print all logs available from libbpf, including debug-level - information. + Print all logs available, even debug-level information. This + includes logs from libbpf as well as from the verifier, when + attempting to load programs. SEE ALSO ======== diff --git a/tools/bpf/bpftool/main.c b/tools/bpf/bpftool/main.c index d74293938a05..4879f6395c7e 100644 --- a/tools/bpf/bpftool/main.c +++ b/tools/bpf/bpftool/main.c @@ -26,6 +26,7 @@ bool pretty_output; bool json_output; bool show_pinned; bool block_mount; +bool verifier_logs; int bpf_flags; struct pinned_obj_table prog_table; struct pinned_obj_table map_table; @@ -373,6 +374,7 @@ int main(int argc, char **argv) break; case 'd': libbpf_set_print(print_all_levels); + verifier_logs = true; break; default: p_err("unrecognized option '%s'", argv[optind - 1]); diff --git a/tools/bpf/bpftool/main.h b/tools/bpf/bpftool/main.h index 3d63feb7f852..28a2a5857e14 100644 --- a/tools/bpf/bpftool/main.h +++ b/tools/bpf/bpftool/main.h @@ -91,6 +91,7 @@ extern json_writer_t *json_wtr; extern bool json_output; extern bool show_pinned; extern bool block_mount; +extern bool verifier_logs; extern int bpf_flags; extern struct pinned_obj_table prog_table; extern struct pinned_obj_table map_table; diff --git a/tools/bpf/bpftool/prog.c b/tools/bpf/bpftool/prog.c index 26336bad0442..1f209c80d906 100644 --- a/tools/bpf/bpftool/prog.c +++ b/tools/bpf/bpftool/prog.c @@ -750,10 +750,11 @@ static int do_detach(int argc, char **argv) static int load_with_options(int argc, char **argv, bool first_prog_only) { - enum bpf_attach_type expected_attach_type; - struct bpf_object_open_attr attr = { - .prog_type = BPF_PROG_TYPE_UNSPEC, + struct bpf_object_load_attr load_attr = { 0 }; + struct bpf_object_open_attr open_attr = { + .prog_type = BPF_PROG_TYPE_UNSPEC, }; + enum bpf_attach_type expected_attach_type; struct map_replace *map_replace = NULL; struct bpf_program *prog = NULL, *pos; unsigned int old_map_fds = 0; @@ -767,7 +768,7 @@ static int load_with_options(int argc, char **argv, bool first_prog_only) if (!REQ_ARGS(2)) return -1; - attr.file = GET_ARG(); + open_attr.file = GET_ARG(); pinfile = GET_ARG(); while (argc) { @@ -776,7 +777,7 @@ static int load_with_options(int argc, char **argv, bool first_prog_only) NEXT_ARG(); - if (attr.prog_type != BPF_PROG_TYPE_UNSPEC) { + if (open_attr.prog_type != BPF_PROG_TYPE_UNSPEC) { p_err("program type already specified"); goto err_free_reuse_maps; } @@ -793,7 +794,8 @@ static int load_with_options(int argc, char **argv, bool first_prog_only) strcat(type, *argv); strcat(type, "/"); - err = libbpf_prog_type_by_name(type, &attr.prog_type, + err = libbpf_prog_type_by_name(type, + &open_attr.prog_type, &expected_attach_type); free(type); if (err < 0) @@ -881,16 +883,16 @@ static int load_with_options(int argc, char **argv, bool first_prog_only) set_max_rlimit(); - obj = __bpf_object__open_xattr(&attr, bpf_flags); + obj = __bpf_object__open_xattr(&open_attr, bpf_flags); if (IS_ERR_OR_NULL(obj)) { p_err("failed to open object file"); goto err_free_reuse_maps; } bpf_object__for_each_program(pos, obj) { - enum bpf_prog_type prog_type = attr.prog_type; + enum bpf_prog_type prog_type = open_attr.prog_type; - if (attr.prog_type == BPF_PROG_TYPE_UNSPEC) { + if (open_attr.prog_type == BPF_PROG_TYPE_UNSPEC) { const char *sec_name = bpf_program__title(pos, false); err = libbpf_prog_type_by_name(sec_name, &prog_type, @@ -960,7 +962,12 @@ static int load_with_options(int argc, char **argv, bool first_prog_only) goto err_close_obj; } - err = bpf_object__load(obj); + load_attr.obj = obj; + if (verifier_logs) + /* log_level1 + log_level2 + stats, but not stable UAPI */ + load_attr.log_level = 1 + 2 + 4; + + err = bpf_object__load_xattr(&load_attr); if (err) { p_err("failed to load object file"); goto err_close_obj; -- cgit